Tornado Chasing.

Science.gov (United States)

Faidley, Warren

1991-01-01

Presents the rationale and purposes behind the phenomenon known as storm chasing, as well as the contributions that tornado chasers have made to both scientific knowledge and public safety. Provides statistical information on tornado frequencies and locations and contact addresses for storm chasers. (JJK)

Multidetector computed tomography with triple-bolus contrast medium administration protocol for preoperative anatomical and functional assessment of potential living renal donors

International Nuclear Information System (INIS)

Knox, Matthew K.; Rivers-Bowerman, Michael D.; Bardgett, Harry P.; Cowan, Nigel C.

2010-01-01

To evaluate multidetector computed tomography (MDCT) with a triple-bolus contrast administration protocol for preoperative anatomical and functional assessment of living renal donors. Fifty-five potential living renal donors underwent MDCT of which 27 proceeded to donor nephrectomy. A triple-bolus contrast administration protocol was used for simultaneous acquisition of arterial, nephrographic, and excretory phases. MDCT images were independently reviewed in random order by two radiologists blinded to surgical anatomy findings. Diagnostic accuracy for anatomical variants was quantified by sensitivity and specificity. Differential renal function (DRF) was derived from MDCT for 54 patients and compared with technetium-99 m dimercaptosuccinic acid renography (Tc-99 m DMSA). All triple-bolus MDCT examinations were technically adequate. Accessory renal arteries and veins were identified at surgery in 33% (n = 9/27) and 22% (n = 6/27) of donor kidneys. The mean difference between MDCT-derived DRF and DMSA was 0.8% (95% CI 0.1-1.6) with 95% limits of agreement of -4.6% (95% CI -3.3 to -5.9) to 6.3% (95% CI 5.0-7.6). MDCT delivered a mean (SD, range) radiation dose of 9.5 (3.6, 3.6-17.3) mSv. MDCT with a triple-bolus contrast administration provides accurate anatomical and functional evaluation of living renal donors. (orig.)

Multidetector computed tomography with triple-bolus contrast medium administration protocol for preoperative anatomical and functional assessment of potential living renal donors

Energy Technology Data Exchange (ETDEWEB)

Knox, Matthew K. [University of Calgary, Faculty of Medicine, UME Office, Health Sciences Centre, Calgary, Alberta (Canada); Rivers-Bowerman, Michael D. [University of British Columbia, Faculty of Medicine, MD Undergraduate Program, Diamond Health Care Centre, Vancouver, British Columbia (Canada); Bardgett, Harry P. [Bradford Teaching Hospitals, Department of Radiology, Bradford (United Kingdom); Cowan, Nigel C. [The Churchill Hospital, Department of Radiology, Oxford (United Kingdom)

2010-11-15

To evaluate multidetector computed tomography (MDCT) with a triple-bolus contrast administration protocol for preoperative anatomical and functional assessment of living renal donors. Fifty-five potential living renal donors underwent MDCT of which 27 proceeded to donor nephrectomy. A triple-bolus contrast administration protocol was used for simultaneous acquisition of arterial, nephrographic, and excretory phases. MDCT images were independently reviewed in random order by two radiologists blinded to surgical anatomy findings. Diagnostic accuracy for anatomical variants was quantified by sensitivity and specificity. Differential renal function (DRF) was derived from MDCT for 54 patients and compared with technetium-99 m dimercaptosuccinic acid renography (Tc-99 m DMSA). All triple-bolus MDCT examinations were technically adequate. Accessory renal arteries and veins were identified at surgery in 33% (n = 9/27) and 22% (n = 6/27) of donor kidneys. The mean difference between MDCT-derived DRF and DMSA was 0.8% (95% CI 0.1-1.6) with 95% limits of agreement of -4.6% (95% CI -3.3 to -5.9) to 6.3% (95% CI 5.0-7.6). MDCT delivered a mean (SD, range) radiation dose of 9.5 (3.6, 3.6-17.3) mSv. MDCT with a triple-bolus contrast administration provides accurate anatomical and functional evaluation of living renal donors. (orig.)

A custom three-dimensional electron bolus technique for optimization of postmastectomy irradiation

International Nuclear Information System (INIS)

Perkins, George H.; McNeese, Marsha D.; Antolak, John A.; Buchholz, Thomas A.; Strom, Eric A.; Hogstrom, Kenneth R.

2001-01-01

Purpose: Postmastectomy irradiation (PMI) is a technically complex treatment requiring consideration of the primary tumor location, possible risk of internal mammary node involvement, varying chest wall thicknesses secondary to surgical defects or body habitus, and risk of damaging normal underlying structures. In this report, we describe the application of a customized three-dimensional (3D) electron bolus technique for delivering PMI. Methods and Materials: A customized electron bolus was designed using a 3D planning system. Computed tomography (CT) images of each patient were obtained in treatment position and the volume to be treated was identified. The distal surface of the wax bolus matched the skin surface, and the proximal surface was designed to conform to the 90% isodose surface to the distal surface of the planning target volume (PTV). Dose was calculated with a pencil-beam algorithm correcting for patient heterogeneity. The bolus was then fabricated from modeling wax using a computer-controlled milling device. To aid in quality assurance, CT images with the bolus in place were generated and the dose distribution was computed using these images. Results: This technique optimized the dose distribution while minimizing irradiation of normal tissues. The use of a single anterior field eliminated field junction sites. Two patients who benefited from this option are described: one with altered chest wall geometry (congenital pectus excavatum), and one with recurrent disease in the medial chest wall and internal mammary chain (IMC) area. Conclusion: The use of custom 3D electron bolus for PMI is an effective method for optimizing dose delivery. The radiation dose distribution is highly conformal, dose heterogeneity is reduced compared to standard techniques in certain suboptimal settings, and excellent immediate outcome is obtained

SU-C-213-03: Custom 3D Printed Boluses for Radiation Therapy

Energy Technology Data Exchange (ETDEWEB)

Zhao, B; Yang, M; Yan, Y; Rahimi, A; Chopra, R; Jiang, S [UT Southwestern Medical Center, Dallas, TX (United States)

2015-06-15

Purpose: To develop a clinical workflow and to commission the process of creating custom 3d printed boluses for radiation therapy. Methods: We designed a workflow to create custom boluses using a commercial 3D printer. Contours of several patients were deformably mapped to phantoms where the test bolus contours were designed. Treatment plans were created on the phantoms following our institutional planning guideline. The DICOM file of the bolus contours were then converted to stereoLithography (stl) file for the 3d printer. The boluses were printed on a commercial 3D printer using polylactic acid (PLA) material. Custom printing parameters were optimized in order to meet the requirement of bolus composition. The workflow was tested on multiple anatomical sites such as skull, nose and chest wall. The size of boluses varies from 6×9cm2 to 12×25cm2. To commission the process, basic CT and dose properties of the printing materials were measured in photon and electron beams and compared against water and soft superflab bolus. Phantoms were then scanned to confirm the placement of custom boluses. Finally dose distributions with rescanned CTs were compared with those computer-generated boluses. Results: The relative electron density(1.08±0.006) of the printed boluses resemble those of liquid tap water(1.04±0.004). The dosimetric properties resemble those of liquid tap water(1.04±0.004). The dosimetric properties were measured at dmax with an ion chamber in electron and photon open beams. Compared with solid water and soft bolus, the output difference was within 1% for the 3D printer material. The printed boluses fit well to the phantom surfaces on CT scans. The dose distribution and DVH based on the printed boluses match well with those based on TPS generated boluses. Conclusion: 3d printing provides a cost effective and convenient solution for patient-specific boluses in radiation therapy.

SU-C-213-03: Custom 3D Printed Boluses for Radiation Therapy

International Nuclear Information System (INIS)

Zhao, B; Yang, M; Yan, Y; Rahimi, A; Chopra, R; Jiang, S

2015-01-01

Purpose: To develop a clinical workflow and to commission the process of creating custom 3d printed boluses for radiation therapy. Methods: We designed a workflow to create custom boluses using a commercial 3D printer. Contours of several patients were deformably mapped to phantoms where the test bolus contours were designed. Treatment plans were created on the phantoms following our institutional planning guideline. The DICOM file of the bolus contours were then converted to stereoLithography (stl) file for the 3d printer. The boluses were printed on a commercial 3D printer using polylactic acid (PLA) material. Custom printing parameters were optimized in order to meet the requirement of bolus composition. The workflow was tested on multiple anatomical sites such as skull, nose and chest wall. The size of boluses varies from 6×9cm2 to 12×25cm2. To commission the process, basic CT and dose properties of the printing materials were measured in photon and electron beams and compared against water and soft superflab bolus. Phantoms were then scanned to confirm the placement of custom boluses. Finally dose distributions with rescanned CTs were compared with those computer-generated boluses. Results: The relative electron density(1.08±0.006) of the printed boluses resemble those of liquid tap water(1.04±0.004). The dosimetric properties resemble those of liquid tap water(1.04±0.004). The dosimetric properties were measured at dmax with an ion chamber in electron and photon open beams. Compared with solid water and soft bolus, the output difference was within 1% for the 3D printer material. The printed boluses fit well to the phantom surfaces on CT scans. The dose distribution and DVH based on the printed boluses match well with those based on TPS generated boluses. Conclusion: 3d printing provides a cost effective and convenient solution for patient-specific boluses in radiation therapy

Chasing as a model of psychogenic stress: characterization of physiological and behavioral responses.

Science.gov (United States)

Lee, Ji-Hye; Kimm, Sunwhi; Han, Jung-Soo; Choi, June-Seek

2018-03-25

Being chased by a predator or a dominant conspecific can induce significant stress. However, only a limited number of laboratory studies have employed chasing by itself as a stressor. In this study, we developed a novel stress paradigm in which rats were chased by a fast-moving object in an inescapable maze. In Experiment 1, defensive behaviors and stress hormone changes induced by chasing stress were measured. During the chasing stress, the chasing-stress group (n = 9) froze and emitted 22-kHz ultrasonic vocalizations (USVs), but the no-chasing control group (n = 10) did not. Plasma corticosterone levels significantly increased following the chasing and were comparable to those of the restraint-stress group (n = 6). In Experiment 2, the long-lasting memory of the chasing event was tested after three weeks. The chasing-stress group (n = 15) showed higher levels of freezing and USV than the no-chasing group (n = 14) when they were presented with the tone associated with the object's chasing action. Subsequently, the rats were subjected to Pavlovian threat conditioning with a tone as a conditioned stimulus and footshock as an unconditioned stimulus. The chasing-stress group showed higher levels of freezing and USV during the conditioning session than the no-chasing group, indicating sensitized defensive reactions in a different threat situation. Taken together, the current results suggest that chasing stress can induce long-lasting memory and sensitization of defensive responses to a new aversive event as well as immediate, significant stress responses.

An application of importance-performance analysis to recreational storm chasing

Science.gov (United States)

Jiawen Chen; Sonja Wilhelm Stanis; Carla Barbieri; Shuangyu. Xu

2012-01-01

Since the release of the movie "Twister" in 1996, storm chasing has become an increasingly popular form of recreation. Storm chasing tour agencies have emerged to provide technical assistance and guidance to individuals wishing to participate in this activity. However, little is known about the participants' perceptions of their storm chasing tours....

Characterization of an intravenously injected bolus

International Nuclear Information System (INIS)

Samuel, A.M.; Raikar, U.R.; Atmaram, S.H.; Ganatra, R.D.

1976-01-01

A study of some parameters affecting the time activity histogram of an intravenous bolus injection of radioactivity was performed. A scoring system for bolus compactness was attempted. A score of 2 and above was considered to be a satisfactory bolus. Volumes less than 1 ml tended to result in a satisfactory bolus. The nature of radiopharmaceutical injected, different injecters and age of the patient did not affect the score. Thyrotoxic patients gave the best bolus score. (orig.) [de

Esophageal contractions, bolus transit and perception of transit after swallows of liquid and solid boluses in normal subjects

Directory of Open Access Journals (Sweden)

Juciléia Dalmazo

2012-12-01

Full Text Available CONTEXT: Esophageal dysphagia is the sensation that the ingested material has a slow transit or blockage in its normal passage to the stomach. It is not always associated with motility or transit alterations. OBJECTIVES: To evaluate in normal volunteers the possibility of perception of bolus transit through the esophagus after swallows of liquid and solid boluses, the differences in esophageal contraction and transit with these boluses, and the association of transit perception with alteration of esophageal contraction and/or transit. METHODS: The investigation included 11 asymptomatic volunteers, 4 men and 7 women aged 19-58 years. The subjects were evaluated in the sitting position. They performed swallows of the same volume of liquid (isotonic drink and solid (macaroni boluses in a random order and in duplicate. After each swallow they were asked about the sensation of bolus passage through the esophagus. Contractions and transit were evaluated simultaneously by solid state manometry and impedance. RESULTS: Perception of bolus transit occurred only with the solid bolus. The amplitude and area under the curve of contractions were higher with swallows of the solid bolus than with swallows of the liquid bolus. The difference was more evident in swallows with no perception of transit (n = 12 than in swallows with perception (n = 10. The total bolus transit time was longer for the solid bolus than for the liquid bolus only with swallows followed by no perception of transit. CONCLUSION: The results suggest that the perception of esophageal transit may be the consequence of inadequate adaptation of esophageal transit and contraction to the characteristics of the swallowed bolus.

The illusion of handy wins: Problem gambling, chasing, and affective decision-making.

Science.gov (United States)

Nigro, Giovanna; Ciccarelli, Maria; Cosenza, Marina

2018-01-01

Chasing losses is a behavioral marker and a diagnostic criterion for gambling disorder. It consists in continuing gambling to recoup previous losses. Although chasing has been recognized playing a central role in gambling disorder, research on this topic is relatively scarce, and it remains unclear whether chasing affects decision-making in behavioral tasks in which participants gain or loss some money. Even if several studies found that the more the gambling involvement, the poorer the decision-making, to date no research investigated the role of chasing in decision-making. The study aimed to first investigate the relation between chasing and decision-making in adult gamblers. One hundred and four VLT players were administered the South Oaks Gambling Screen (SOGS), a computerized task measuring chasing, and the Iowa Gambling Task (IGT). Correlation analysis showed that the higher the SOGS scores, the higher the propensity to chase, and the poorer the decision-making performance. Regression analysis revealed that chasing propensity and gambling severity predicted IGT performance. Mediation analysis indicated that the association between gambling severity and poor decision-making is mediated by chasing. Gambling severity was assessed by means of a self-report measure. The generalizability of findings is limited, since the study focused only on VLT players. This study provides the first evidence that chasing, along with gambling severity, affects decision-making, at least in behavioral tasks involving money. Since chasers and non-chasers could be two different sub-types of gamblers, treatment protocols should take into account the additive role of chasing in gambling disorder. Copyright © 2017 Elsevier B.V. All rights reserved.

Commentary on "Performance of a glucose meter with a built-in automated bolus calculator versus manual bolus calculation in insulin-using subjects".

Science.gov (United States)

Rossetti, Paolo; Vehí, Josep; Revert, Ana; Calm, Remei; Bondia, Jorge

2012-03-01

Since the early 2000s, there has been an exponentially increasing development of new diabetes-applied technology, such as continuous glucose monitoring, bolus calculators, and "smart" pumps, with the expectation of partially overcoming clinical inertia and low patient compliance. However, its long-term efficacy in glucose control has not been unequivocally proven. In this issue of Journal of Diabetes Science and Technology, Sussman and colleagues evaluated a tool for the calculation of the prandial insulin dose. A total of 205 insulin-treated patients were asked to compute a bolus dose in two simulated conditions either manually or with the bolus calculator built into the FreeStyle InsuLinx meter, revealing the high frequency of wrong calculations when performed manually. Although the clinical impact of this study is limited, it highlights the potential implications of low diabetesrelated numeracy in poor glycemic control. Educational programs aiming to increase patients' empowerment and caregivers' knowledge are needed in order to get full benefit of the technology. © 2012 Diabetes Technology Society.

Alexithymia predicts loss chasing for people at risk for problem gambling.

Science.gov (United States)

Bibby, Peter A; Ross, Katherine E

2017-12-01

Background and aims The aim of this research was to investigate the relationship between alexithymia and loss-chasing behavior in people at risk and not at risk for problem gambling. Methods An opportunity sample of 58 (50 males and 8 females) participants completed the Problem Gambling Severity Index and the Toronto Alexithymia Scale (TAS-20). They then completed the Cambridge Gambling Task from which a measure of loss-chasing behavior was derived. Results Alexithymia and problem gambling risk were significantly positively correlated. Subgroups of non-alexithymic and at or near caseness for alexithymia by low risk and at risk for problem gambling were identified. The results show a clear difference for loss-chasing behavior for the two alexithymia conditions, but there was no evidence that low and at-risk problem gamblers were more likely to loss chase. The emotion-processing components of the TAS-20 were shown to correlate with loss chasing. Discussion and conclusion These findings suggest that loss-chasing behavior may be particularly prevalent in a subgroup of problem gamblers those who are high in alexithymia.

Chases and escapes the mathematics of pursuit and evasion

CERN Document Server

Nahin, Paul J

2012-01-01

We all played tag when we were kids. What most of us don't realize is that this simple chase game is in fact an application of pursuit theory, and that the same principles of games like tag, dodgeball, and hide-and-seek are also at play in military strategy, high-seas chases by the Coast Guard, and even romantic pursuits. In Chases and Escapes, Paul Nahin gives us the first complete history of this fascinating area of mathematics, from its classical analytical beginnings to the present day. Drawing on game theory, geometry, linear algebra, target-tracking algorithms, and much

75 FR 31510 - Fox Chase Bancorp, Inc., Hatboro, PA; Approval of Conversion

Science.gov (United States)

2010-06-03

... DEPARTMENT OF THE TREASURY Office of Thrift Supervision [AC-43: OTS No. H-4707] Fox Chase Bancorp, Inc., Hatboro, PA; Approval of Conversion Application Notice is hereby given that on May 14, 2010, the Office of Thrift Supervision approved the application of Fox Chase MHC and Fox Chase Bank, Hatboro...

Bolus use in radiotherapy

Directory of Open Access Journals (Sweden)

Sérgio Spezzia

2017-01-01

Full Text Available Preliminary to the radiation therapy, it is posisble to develop a therapeutic device contained in the buccomaxillofacial prosthesis resources, creating the bolus. Bolus are materials used to increase the dose on the entrance surface of a field or to compensate for a lack of tissue. The requirements for a material to be used as a bolus include to interact with ionizing radiations in a similar manner to tissues and to be soft enough to allow its molding to the patient’s contour. There are various materials available for this purpose, however, with a relatively high cost. Some inexpensive options can also be used, such as pressed cellophane and wet gauze, however, these materials do not present favorable malleability and do not offer true reproducibility. The aim of this article was to ascertain whether there is harmonious knowledge of this technique by dental surgeons, medical oncologists and radiotherapists. This technique or device minimizes the deleterious effects resulting from exposure to radiation. It was concluded the bolus can reduce possible complications arising from radiation therapy, concomitantly offering improved living conditions during treatment.

Electrical characterization of bolus material as phantom for use in electrical impedance and computed tomography fusion imaging

Directory of Open Access Journals (Sweden)

Parvind Kaur Grewal

2014-04-01

Full Text Available Phantoms are widely used in medical imaging to predict image quality prior to clinical imaging. This paper discusses the possible use of bolus material, as a conductivity phantom, for validation and interpretation of electrical impedance tomography (EIT images. Bolus is commonly used in radiation therapy to mimic tissue. When irradiated, it has radiological characteristics similar to tissue. With increased research interest in CT/EIT fusion imaging there is a need to find a material which has both the absorption coefficient and electrical conductivity similar to biological tissues. In the present study the electrical properties, specifically resistivity, of various commercially available bolus materials were characterized by comparing their frequency response with that of in-vivo connective adipose tissue. It was determined that the resistivity of Gelatin Bolus is similar to in-vivo tissue in the frequency range 10 kHz to 1MHz and therefore has potential to be used in EIT/CT fusion imaging studies.

The CHASE laboratory search for chameleon dark energy

International Nuclear Information System (INIS)

Steffen, Jason H.

2010-01-01

A scalar field is a favorite candidate for the particle responsible for dark energy. However, few theoretical means exist that can simultaneously explain the observed acceleration of the Universe and evade tests of gravity. The chameleon mechanism, whereby the properties of a particle depend upon the local environment, is one possible avenue. We present the results of the Chameleon Afterglow Search (CHASE) experiment, a laboratory probe for chameleon dark energy. CHASE marks a significant improvement other searches for chameleons both in terms of its sensitivity to the photon/chameleon coupling as well as its sensitivity to the classes of chameleon dark energy models and standard power-law models. Since chameleon dark energy is virtually indistinguishable from a cosmological constant, CHASE tests dark energy models in a manner not accessible to astronomical surveys.

The CHASE laboratory search for chameleon dark energy

Energy Technology Data Exchange (ETDEWEB)

Steffen, Jason [Fermi National Accelerator Laboratory - Fermilab, P.O. Box 500, Batavia, IL 60510-5011 (United States)

2010-07-01

A scalar field is a favorite candidate for the particle responsible for dark energy. However, few theoretical means exist that can simultaneously explain the observed acceleration of the Universe and evade tests of gravity. The chameleon mechanism, whereby the properties of a particle depend upon the local environment, is one possible avenue. I present the results of the Chameleon Afterglow Search (CHASE) experiment, a laboratory probe for chameleon dark energy. CHASE marks a significant improvement over other searches for chameleons both in terms of its sensitivity to the photon/chameleon coupling as well as its sensitivity to the classes of chameleon dark energy models and standard power-law models. Since chameleon dark energy is virtually indistinguishable from a cosmological constant, CHASE tests dark energy models in a manner not accessible to astronomical surveys. (author)

Comprehensive MRA of the lower limbs including high-resolution extended-phase infra-inguinal imaging with gadobenate dimeglumine: Initial experience with inter-individual comparison to the blood-pool contrast agent gadofosveset trisodium

International Nuclear Information System (INIS)

Christie, A.; Chandramohan, S.; Roditi, G.

2013-01-01

Aim: To compare extended-phase imaging using an extracellular space contrast agent, gadobenate dimeglumine, to imaging with a blood-pool contrast agent, gadofosveset, for magnetic resonance angiography. Materials and methods: A lower-limb magnetic resonance angiography (MRA) protocol (dynamic crural, three-station bolus chase, and infra-inguinal high resolution) designed for blood-pool agent imaging was adapted for use with the extracellular agent, gadobenate dimeglumine, primarily by using a triphasic injection protocol. Ten patients scanned with gadofosveset were compared to 10 patients scanned with gadobenate. The dynamic, bolus chase, and high-resolution images were scored for quality on a Likert scale (from 1–5). Signal- and contrast-to-noise ratios were analysed, and Mann–Whitney U statistical analysis performed. Results: There was no significant difference for the dynamic imaging or the aorto-iliac station of the bolus chase. Infra-inguinal bolus chase images were higher quality (p < 0.05 Mann–Whitney U test) with gadobenate. Signal analysis confirmed lower signal and contrast for venous imaging on the high spatial resolution acquisitions with gadobenate; however, this allowed improved arterial conspicuity. Conclusion: Extended-phase imaging using an extracellular space contrast agent is feasible and provides image quality to equal imaging with a blood-pool contrast agent.

Paper Chase and the Socratic Method of Teaching Law.

Science.gov (United States)

Dillon, J. T.

1980-01-01

It is argued that the Socratic method of teaching law as depicted in the book, movie, and TV series "Paper Chase" is not really the Socratic method at all. The genuine Socratic method and the questioning technique used in "Paper Chase" are examined and their appropriateness and effectiveness as methods for teaching contract law…

Bolus injections of measured amounts of radioactivity

International Nuclear Information System (INIS)

Wesolowski, C.A.; Hogendoorn, P.; Vandierendonck, R.; Driedger, A.A.

1988-01-01

Many time-based radionuclide techniques, such as glomerular filtration rate measurement (GFR), require prompt intravenous delivery of and accurately measured tracer bolus with minimal residual tracer retention at the injection site. The quality assurance aspects of two antecubital vein, quantitative injection techniques were investigated. A flush bolus technique using a tuberculin syringe piggybacked onto a 10-ml saline flush was compared to a single blood pressure cuff injection technique. Scintillation camera data for each technique were compared for bolus duration in the abdominal aorta and for residual activity at the injection site at 5 min. Bolus times were measured as the FWHM of the gamma variate fit to the abdominal aortic regional time-activity curves. Relatively little focal activity was seen in the antecubital injection site following the flush bolus: marked residual activity was seen following the blood pressure cuff injections. The injection site/arm background ratios averaged 1.3 for the flush bolus and 30.1 for the cuff technique. Although both methods allowed accurate in vitro determination of administered radioactivity, only the tuberculin syringe flush bolus technique was acceptable for time-based quantitation because of its superior in vivo characteristics

Child and adolescent service experience (ChASE): measuring service quality and therapeutic process.

Science.gov (United States)

Day, Crispin; Michelson, Daniel; Hassan, Imren

2011-11-01

OBJECTIVES. Dissatisfaction with services has been associated with poorer child mental health outcomes, early treatment termination as well as disagreements over the nature of mental health difficulties, reasons for referral and therapy goals. The development of straightforward, reliable, and accurate methods of eliciting service users' views is essential within child and adolescent mental health care. This paper describes the development of the child and adolescent service experience (ChASE), a tool to measure children and young people's service experience DESIGN. The study comprises a non-experimental, cross-sectional design. METHODS. Participants were 132 mental health service users aged 8-18 years. Participants and their main carer completed the ChASE, Parent Satisfaction Questionnaire (PSQ) (Stallard, 1996) and Strengths and Difficulties (SDQ) Impact Supplement. Clinicians completed the SDQ Impact Supplement and provided clinical activity data. A sub-sample of participants completed the ChASE on a second occasion, 6 weeks after the completion of the first questionnaire. RESULTS. Scrutiny of ChASE data indicated high levels of completion. Principal axis factoring identified three factors within the ChASE: Relationship, Privacy, and Session Activity. The ChASE has good internal consistency and test-retest reliability. Significant correlations were found between the ChASE and carer satisfaction, service use, and youth clinical outcomes. CONCLUSIONS. The ChASE is a short, psychometrically robust tool for routine measurement of children, and young people's experience of mental health services, which users can complete easily. The results underline the importance of alliance factors to children and young people and their association with clinical improvement as well as the potential for the ChASE to be used a measure of children's therapeutic progress and alliance. ©2011 The British Psychological Society.

A Vicious Cycle: A Cross-Sectional Study of Canine Tail-Chasing and Human Responses to It, Using a Free Video-Sharing Website

Science.gov (United States)

Burn, Charlotte C.

2011-01-01

Tail-chasing is widely celebrated as normal canine behaviour in cultural references. However, all previous scientific studies of tail-chasing or ‘spinning’ have comprised small clinical populations of dogs with neurological, compulsive or other pathological conditions; most were ultimately euthanased. Thus, there is great disparity between scientific and public information on tail-chasing. I gathered data on the first large (n = 400), non-clinical tail-chasing population, made possible through a vast, free, online video repository, YouTube™. The demographics of this online population are described and discussed. Approximately one third of tail-chasing dogs showed clinical signs, including habitual (daily or ‘all the time’) or perseverative (difficult to distract) performance of the behaviour. These signs were observed across diverse breeds. Clinical signs appeared virtually unrecognised by the video owners and commenting viewers; laughter was recorded in 55% of videos, encouragement in 43%, and the commonest viewer descriptors were that the behaviour was ‘funny’ (46%) or ‘cute’ (42%). Habitual tail-chasers had 6.5+/−2.3 times the odds of being described as ‘Stupid’ than other dogs, and perseverative dogs were 6.8+/−2.1 times more frequently described as ‘Funny’ than distractible ones were. Compared with breed- and age-matched control videos, tail-chasing videos were significantly more often indoors and with a computer/television screen switched on. These findings highlight that tail-chasing is sometimes pathological, but can remain untreated, or even be encouraged, because of an assumption that it is ‘normal’ dog behaviour. The enormous viewing figures that YouTube™ attracts (mean+/−s.e. = 863+/−197 viewings per tail-chasing video) suggest that this perception will be further reinforced, without effective intervention. PMID:22096487

A vicious cycle: a cross-sectional study of canine tail-chasing and human responses to it, using a free video-sharing website.

Directory of Open Access Journals (Sweden)

Charlotte C Burn

Full Text Available Tail-chasing is widely celebrated as normal canine behaviour in cultural references. However, all previous scientific studies of tail-chasing or 'spinning' have comprised small clinical populations of dogs with neurological, compulsive or other pathological conditions; most were ultimately euthanased. Thus, there is great disparity between scientific and public information on tail-chasing. I gathered data on the first large (n = 400, non-clinical tail-chasing population, made possible through a vast, free, online video repository, YouTube™. The demographics of this online population are described and discussed. Approximately one third of tail-chasing dogs showed clinical signs, including habitual (daily or 'all the time' or perseverative (difficult to distract performance of the behaviour. These signs were observed across diverse breeds. Clinical signs appeared virtually unrecognised by the video owners and commenting viewers; laughter was recorded in 55% of videos, encouragement in 43%, and the commonest viewer descriptors were that the behaviour was 'funny' (46% or 'cute' (42%. Habitual tail-chasers had 6.5+/-2.3 times the odds of being described as 'Stupid' than other dogs, and perseverative dogs were 6.8+/-2.1 times more frequently described as 'Funny' than distractible ones were. Compared with breed- and age-matched control videos, tail-chasing videos were significantly more often indoors and with a computer/television screen switched on. These findings highlight that tail-chasing is sometimes pathological, but can remain untreated, or even be encouraged, because of an assumption that it is 'normal' dog behaviour. The enormous viewing figures that YouTube™ attracts (mean+/-s.e. = 863+/-197 viewings per tail-chasing video suggest that this perception will be further reinforced, without effective intervention.

Chelate chase of radiopharmaceuticals reversibly bound to monoclonal antibodies improves dosimetry

International Nuclear Information System (INIS)

Goodwin, D.A.; Smith, S.I.; Meares, C.F.; David, G.S.; McTigue, M.; Finston, R.A.

1986-01-01

One hundred micrograms of monoclonal antibody (MoAb) CHA 255 with a binding constant Kb of 4 x 10 9 was complexed with indium-111 labeled BLEDTA II, GLEDTA IV, benzyl EDTA, and an EDTA conjugate of Fab. The 24-hour tumor and organ distribution in BALB/c mice bearing KHJJ tumors was studied for each compound alone, the antibody complex, and 3 hours following a chelate chase of the antibody complex. Whole-body biological half-life was measured for 7 days with and without a chelate chase for each antibody complex. The 24-hour whole-body counts dropped 20-60% within 3 hours of administering the chelate chase. Blood concentration fell over 89% within 3 hours of administering the chase and there was a decrease in concentration in all organs, except the kidneys, of 10 to 85%. Theoretical equivalent human doses were calculated from the 24-hour organ concentrations, effective half-life, and MIRD 11 S values (absorbed dose per cumulated activity). Liver and spleen were the target organs, with the dose ranging from 0.50 to 3.91 rads per millicurie. The reduction in organ radiation dose varied up to 95% following the chelate chase. Rapid selective renal clearance of chelate labeled radiopharmaceuticals by competitive inhibition (chelate chase) of their reversible binding to monoclonal antibodies, greatly improves the radiation dosimetry of tumor imaging agents. 28 references, 5 figures, 5 tables

Tranexamic Acid in Bolus Alone Vs Bolus and Continuous Infusion in Hip Arthroscopy

OpenAIRE

Fatih Karaaslan; Roberto Seijas; Andrea Sallent; Oscar Ares; Wenceslao Espinosa; Pedro Alvarez; Ramón Cugat; Patricia Lopez

2017-01-01

AIM: the present study examines the effects of tranexamic acid (TXA) on reducing blood loss during hip arthroscopy, comparing two different methods of administration (bolus vs infusion). METHODS: a prospective study with 70 patients undergoing hip arthroscopy was carried out. The patients within the TXA infusion group (group A) received TXA an 2-g intravenous bolus 30 min before skin incision intravenously followed by 10 mg/kg/h infusion (continued during the entire surgery)...

Comparison and evaluation between 3D-bolus and step-bolus, the assistive radiotherapy devices for the patients who had undergone modified radical mastectomy surgery

Energy Technology Data Exchange (ETDEWEB)

Jang, Won Seok; Park, Kwang Woo; Shin, Dong Bong; Kim, Jong Dae; Kim, Sei Joon; Ha, Jin Sook; Jeon, Mi Jin; Cho, Yoojin; Jung, Inho [Dept. of Radiation Oncology, Gangnam Severance Hospital, Seoul, (Korea, Republic of)

2016-06-15

This study aimed to compare and evaluate between the efficiency of two respective devices, 3D-bolus and step-bolus when the devices were used for the treatment of patients whose chest walls were required to undergo the electron beam therapy after the surgical procedure of modified radical mastectomy, MRM. The treatment plan of reverse hockey stick method, using the photon beam and electron beam, had been set for six breast cancer patients and these 6 breast cancer patients were selected to be the subjects for this study. The prescribed dose of electron beam for anterior chest wall was set to be 180 cGy per treatment and both the 3D-bolus, produced using 3D printer(CubeX, 3D systems, USA) and the self-made conventional step-bolus were used respectively. The surface dose under 3D-bolus and step-bolus was measured at 5 measurement spots of iso-center, lateral, medial, superior and inferior point, using GAFCHROMIC EBT3 film (International specialty products, USA) and the measured value of dose at 5 spots was compared and analyzed. Also the respective treatment plan was devised, considering the adoption of 3D-bolus and stepbolus and the separate treatment results were compared to each other. The average surface dose was 179.17 cGy when the device of 3D-bolus was adopted and 172.02 cGy when step-bolus was adopted. The average error rate against the prescribed dose of 180 cGy was -(minus) 0.47% when the device of 3D-bolus was adopted and it was -(minus) 4.43% when step-bolus was adopted. It was turned out that the maximum error rate at the point of iso-center was 2.69%, in case of 3D-bolus adoption and it was 5,54% in case of step-bolus adoption. The maximum discrepancy in terms of treatment accuracy was revealed to be about 6% when step-bolus was adopted and to be about 3% when 3D-bolus was adopted. The difference in average target dose on chest wall between 3D-bolus treatment plan and step-bolus treatment plan was shown to be insignificant as the difference was only 0

Comparison and evaluation between 3D-bolus and step-bolus, the assistive radiotherapy devices for the patients who had undergone modified radical mastectomy surgery

International Nuclear Information System (INIS)

Jang, Won Seok; Park, Kwang Woo; Shin, Dong Bong; Kim, Jong Dae; Kim, Sei Joon; Ha, Jin Sook; Jeon, Mi Jin; Cho, Yoojin; Jung, Inho

2016-01-01

This study aimed to compare and evaluate between the efficiency of two respective devices, 3D-bolus and step-bolus when the devices were used for the treatment of patients whose chest walls were required to undergo the electron beam therapy after the surgical procedure of modified radical mastectomy, MRM. The treatment plan of reverse hockey stick method, using the photon beam and electron beam, had been set for six breast cancer patients and these 6 breast cancer patients were selected to be the subjects for this study. The prescribed dose of electron beam for anterior chest wall was set to be 180 cGy per treatment and both the 3D-bolus, produced using 3D printer(CubeX, 3D systems, USA) and the self-made conventional step-bolus were used respectively. The surface dose under 3D-bolus and step-bolus was measured at 5 measurement spots of iso-center, lateral, medial, superior and inferior point, using GAFCHROMIC EBT3 film (International specialty products, USA) and the measured value of dose at 5 spots was compared and analyzed. Also the respective treatment plan was devised, considering the adoption of 3D-bolus and stepbolus and the separate treatment results were compared to each other. The average surface dose was 179.17 cGy when the device of 3D-bolus was adopted and 172.02 cGy when step-bolus was adopted. The average error rate against the prescribed dose of 180 cGy was -(minus) 0.47% when the device of 3D-bolus was adopted and it was -(minus) 4.43% when step-bolus was adopted. It was turned out that the maximum error rate at the point of iso-center was 2.69%, in case of 3D-bolus adoption and it was 5,54% in case of step-bolus adoption. The maximum discrepancy in terms of treatment accuracy was revealed to be about 6% when step-bolus was adopted and to be about 3% when 3D-bolus was adopted. The difference in average target dose on chest wall between 3D-bolus treatment plan and step-bolus treatment plan was shown to be insignificant as the difference was only 0

A study on developing customized bolus using 3D prints

International Nuclear Information System (INIS)

Jung, Sang Min; Yang, Jin Ho; Lee, Seung Hyun; Kim, Jin Uk; Yeom, Du Seok

2015-01-01

3D Printers are used to create three-dimensional models based on blueprints. Based on this characteristic, it is feasible to develop a bolus that can minimize the air gap between skin and bolus in radiotherapy. This study aims to compare and analyze air gap and target dose at the branded 1 cm bolus with the developed customized bolus using 3D printers. RANDO phantom with a protruded tumor was used to procure images using CT simulator. CT DICOM file was transferred into the STL file, equivalent to 3D printers. Using this, customized bolus molding box (maintaining the 1 cm width) was created by processing 3D printers, and paraffin was melted to develop the customized bolus. The air gap of customized bolus and the branded 1 cm bolus was checked, and the differences in air gap was used to compare D max , D min , D mean , D 95% and V 95% in treatment plan through Eclipse. Customized bolus production period took about 3 days. The total volume of air gap was average 3.9 cm 3 at the customized bolus. And it was average 29.6cm 3 at the branded 1 cm bolus. The customized bolus developed by the 3D printer was more useful in minimizing the air gap than the branded 1 cm bolus. In the 6 MV photon, at the customized bolus, D max , D min , D mean , D 95% , V 95% of GTV were 102.8%, 88.1%, 99.1%, 95.0%, 94.4% and the D max , D min , D mean , D 95% , V 95% of branded 1 cm bolus were 101.4%, 92.0%, 98.2%, 95.2%, 95.7%, respectively. In the proton, at the customized bolus, D max , D min , D mean , D 95% , V 95% of GTV were 104.1%, 84.0%, 101.2%, 95.1%, 99.8% and the D max , D min , D mean , D 95% , V 95% of branded 1cm bolus were 104.8%, 87.9%, 101.5%, 94.9%, 99.9%, respectively. Thus, in treatment plan, there was no significant difference between the customized bolus and 1 cm bolus. However, the normal tissue nearby the GTV showed relatively lower radiation dose. The customized bolus developed by 3D printers was effective in minimizing the air gap, especially when it is used against

A study on developing customized bolus using 3D prints

Energy Technology Data Exchange (ETDEWEB)

Jung, Sang Min; Yang, Jin Ho; Lee, Seung Hyun; Kim, Jin Uk; Yeom, Du Seok [Dept. of Proton Therapy Center, National Cancer Center, Ilsan (Korea, Republic of)

2015-06-15

3D Printers are used to create three-dimensional models based on blueprints. Based on this characteristic, it is feasible to develop a bolus that can minimize the air gap between skin and bolus in radiotherapy. This study aims to compare and analyze air gap and target dose at the branded 1 cm bolus with the developed customized bolus using 3D printers. RANDO phantom with a protruded tumor was used to procure images using CT simulator. CT DICOM file was transferred into the STL file, equivalent to 3D printers. Using this, customized bolus molding box (maintaining the 1 cm width) was created by processing 3D printers, and paraffin was melted to develop the customized bolus. The air gap of customized bolus and the branded 1 cm bolus was checked, and the differences in air gap was used to compare D{sub max}, D{sub min}, D{sub mean}, D{sub 95%} and V{sub 95%} in treatment plan through Eclipse. Customized bolus production period took about 3 days. The total volume of air gap was average 3.9 cm{sup 3} at the customized bolus. And it was average 29.6cm{sup 3} at the branded 1 cm bolus. The customized bolus developed by the 3D printer was more useful in minimizing the air gap than the branded 1 cm bolus. In the 6 MV photon, at the customized bolus, D{sub max}, D{sub min}, D{sub mean}, D{sub 95%}, V{sub 95%} of GTV were 102.8%, 88.1%, 99.1%, 95.0%, 94.4% and the D{sub max}, D{sub min}, D{sub mean}, D{sub 95%}, V{sub 95%} of branded 1 cm bolus were 101.4%, 92.0%, 98.2%, 95.2%, 95.7%, respectively. In the proton, at the customized bolus, D{sub max}, D{sub min}, D{sub mean}, D{sub 95%}, V{sub 95%} of GTV were 104.1%, 84.0%, 101.2%, 95.1%, 99.8% and the D{sub max}, D{sub min}, D{sub mean}, D{sub 95%}, V{sub 95%} of branded 1cm bolus were 104.8%, 87.9%, 101.5%, 94.9%, 99.9%, respectively. Thus, in treatment plan, there was no significant difference between the customized bolus and 1 cm bolus. However, the normal tissue nearby the GTV showed relatively lower radiation dose. The

Pharyngeal Pressure and Timing During Bolus Transit

Science.gov (United States)

Walczak, Chelsea C.; Jones, Corinne A.; McCulloch, Timothy M.

2018-01-01

Determining intrabolus pressure (IBP) at the upper esophageal sphincter (UES) and in the esophagus has given compelling evidence that IBP can be a predictor for swallowing dysfunction. Studies have looked most superiorly at the low hypopharynx region but there has been no inquiry into what IBP measures throughout the entire pharynx can tell us. We present a study to describe the pressures within and surrounding the moving bolus throughout the pharynx and into the UES. Simultaneous HRM and videofluoroscopy were performed in 10 healthy subjects swallowing ten 10 mL thin-liquid barium boluses. Three events surrounding bolus movement were tracked via videofluoroscopy, two additional events were found using manometric measures. As the bolus passes through the pharynx, low pressure is created at and below the head of the bolus. A modest pressure increase is seen as the bolus passes through the pharynx and finally, high pressure is observed at the bolus tail, followed by an even larger pressure generation of a clearance event. HRM allows for greater resolution in data collection in the pharynx and in this study, aided in identifying semi unique characteristics around the hypopharynx and the UES which are consistent with the complex anatomy of the regions and the transition of the UES from active closure to relaxed opening. In the future, additional studies designed to look at aged and diseased populations may lead to better understanding of disease etiology, and treatment options. PMID:27565155

Usefulness of the Bolus-Tracking Baseline Scan for the Diagnosis of Hepatic Steatosis in Abdominal Computed Tomography: A Feasibility Study

International Nuclear Information System (INIS)

Gossner, J.; Schäfer, S.

2013-01-01

Nonalcoholic fatty liver disease (NAFLD) is a common pathology in western societies. Unenhanced computed tomography (CT) of the liver is a valuable tool in determining the presence of steatosis hepatis, but in most departments standard CT protocols of abdomen often do not include unenhanced scans anymore. In a small series of 22 patients the liver density was measured in the acquired low-dose baseline scan for bolus tracking and was compared to the measurement in a regular unenhanced CT scan of the upper abdomen. The mean difference between the unenhanced CT scan and the low-dose baseline scan was 3.4 HU (range 0.2–8.6 HU); the difference between these two scans was 5 HU or smaller in 82% of the patients. There was a significant difference between the two used CT scanners; this has to be kept in mind before implementing this approach into daily practice. All but one patient with fatty liver disease on unenhanced CT were diagnosed using the baseline scan. The baseline scan for bolus tracking may be useful for the diagnosis or in the followup of fatty liver disease

Avidin chase can reduce myelotoxicity associated with radioimmunotherapy of experimental liver micrometastases in mice

International Nuclear Information System (INIS)

Sato, Noriko; Saga, Tsuneo; Sakahara, Harumi; Nakamoto, Yuji; Zhao, Songji; Iida, Yasuhiko; Konishi, Junji; Kuroki, Masahide; Endo, Keigo

2000-01-01

Myelotoxicity is the main factor which decides the maximum tolerated dose (MTD) in radioimmunotherapy (RIT). Since bone marrow is mostly irradiated from blood radioactivity, enhancing the clearance of unbound circulating radiolabeled antibody is important to reduce myelotoxicity and to increase the MTD. We applied the avidin chase method, which was devised to obtain high tumor-to-background ratios in tumor-targeting, to RIT of experimental liver micrometastases and evaluated its influence on the side effects and therapeutic outcome. Seven days after intrasplenic injection of human colon cancer LS174T cells, nude mice were intravenously injected with biotinylated 131 I-labeled anti-CEA monoclonal antibody (MAb) (24-38 μg, 11.1 MBq). Mice of the chase group then received an intravenous injection of avidin twice (24 and 30 h, 72-115 μg each). Biodistribution, side effects (white blood cell counts and body weight change), and short- and long-term therapeutic effects were determined. Avidin chase markedly accelerated the clearance of radiolabeled MAb from the blood (P<0.0001) and normal tissues, resulting in milder leukocytopenia and body weight loss, both of which recovered earlier than in the non-chase group (P<0.01). The tumor uptake of radiolabeled MAb was also decreased by avidin chase, but the metastases-to-background ratios were increased. Avidin chase gave the therapeutic gain ratio of 1.89. Treated groups with and without avidin chase showed significant therapeutic effects compared to the non-treated group. There was no significant difference in the therapeutic effects between the two treated groups. Avidin chase effectively reduced the side effects of RIT and should increase the MTD. (author)

Practice Change From Intermittent Medication Boluses to Bolusing From a Continuous Infusion in Pediatric Critical Care: A Quality Improvement Project.

Science.gov (United States)

Hochstetler, Jessica L; Thompson, A Jill; Ball, Natalie M; Evans, Melissa C; Frame, Shaun C; Haney, A Lauren; Little, Amelia K; O'Donnell, Jaime L; Rickett, Bryna M; Mack, Elizabeth H

2018-04-12

To determine whether implementing a guideline to bolus medications from continuous infusions in PICUs affects nursing satisfaction, patient safety, central line entries, medication utilization, or cost. This is a pre- and postimplementation quality improvement study. An 11-bed ICU and 14-bed cardiac ICU in a university-affiliated children's hospital. Patients less than 18 years old admitted to the PICU or pediatric cardiac ICU receiving a continuous infusion of dexmedetomidine, midazolam, fentanyl, morphine, vecuronium, or cisatracurium from May 2015 to May 2016, excluding November 2015 (washout period), were eligible for inclusion. Change in practice from administering bolus doses from an automated dispensing machine to administering bolus medications from continuous infusion in PICUs. Timing studies were conducted pre- and post implementation in 29 and 26 occurrences, respectively. The median time from the decision to give a bolus until it began infusing decreased by 169 seconds (p 0.05). Annualized cost avoidance was $124,160. Implementation of bolus medications from continuous infusion in PICUs significantly decreased time to begin a bolus dose and increased nursing satisfaction. The practice change also improved medication utilization without negatively impacting patient safety.

Technology for bolus verification in proton therapy

Science.gov (United States)

Shipulin, K. N.; Mytsin, G. V.; Agapov, A. V.

2015-01-01

To ensure the conformal depth-dose distribution of a proton beam within a target volume, complex shaped range shifters (so-called boluses), which account for the heterogeneous structure of patient tissue and organs in the beam path, were calculated and manufactured. The precise manufacturing of proton compensators used for patient treatment is a vital step in quality assurance in proton therapy. In this work a software-hardware complex that verifies the quality and precision of bolus manufacturing at the Medico-Technical Complex (MTC) was developed. The boluses consisted of a positioning system with two photoelectric biosensors. We evaluated 20 boluses used in proton therapy of five patients. A total number of 2562 experimental points were measured, of which only two points had values that differed from the calculated value by more than 0.5 mm. The other data points displayed a deviation within ±0.5 mm from the calculated value. The technology for bolus verification developed in this work can be used for the high precision testing of geometrical parameters of proton compensators in radiotherapy.

Split-bolus single-phase cardiac multidetector computed tomography for reliable detection of left atrial thrombus. Comparison to transesophageal echocardiography

Energy Technology Data Exchange (ETDEWEB)

Staab, W.; Zwaka, P.A.; Sohns, J.M.; Schwarz, A.; Lotz, J. [University Medical Center Goettingen Univ. (Germany). Inst. for Diagnostic and Interventional Radiology; Sohns, C.; Vollmann, D.; Zabel, M.; Hasenfuss, G. [Goettingen Univ. (Germany). Dept. of Cardiology and Pneumology; Schneider, S. [Goettingen Univ. (Germany). Dept. of Medical Statistics

2014-11-15

Evaluation of a new cardiac MDCT protocol using a split-bolus contrast injection protocol and single MDCT scan for reliable diagnosis of LA/LAA thrombi in comparison to TEE, optimizing radiation exposure and use of contrast agent. A total of 182 consecutive patients with drug refractory AF scheduled for PVI (62.6% male, mean age: 64.1 ± 10.2 years) underwent routine diagnostic work including TEE and cardiac MDCT for the evaluation of LA/LAA anatomy and thrombus formation between November 2010 and March 2012. Contrast media injection was split into a pre-bolus of 30 ml and main bolus of 70 ml iodinated contrast agent separated by a short time delay. In this study, split-bolus cardiac MDCT identified 14 of 182 patients with filling defects of the LA/LAA. In all of these 14 patients, abnormalities were found in TEE. All 5 of the 14 patients with thrombus formation in cardiac MDCT were confirmed by TEE. MDCT was 100% accurate for thrombus, with strong but not perfect overall results for SEC equivalent on MDCT.

What are the underlying units of perceived animacy? Chasing detection is intrinsically object-based.

Science.gov (United States)

van Buren, Benjamin; Gao, Tao; Scholl, Brian J

2017-10-01

One of the most foundational questions that can be asked about any visual process is the nature of the underlying 'units' over which it operates (e.g., features, objects, or spatial regions). Here we address this question-for the first time, to our knowledge-in the context of the perception of animacy. Even simple geometric shapes appear animate when they move in certain ways. Do such percepts arise whenever any visual feature moves appropriately, or do they require that the relevant features first be individuated as discrete objects? Observers viewed displays in which one disc (the "wolf") chased another (the "sheep") among several moving distractor discs. Critically, two pairs of discs were also connected by visible lines. In the Unconnected condition, both lines connected pairs of distractors; but in the Connected condition, one connected the wolf to a distractor, and the other connected the sheep to a different distractor. Observers in the Connected condition were much less likely to describe such displays using mental state terms. Furthermore, signal detection analyses were used to explore the objective ability to discriminate chasing displays from inanimate control displays in which the wolf moved toward the sheep's mirror-image. Chasing detection was severely impaired on Connected trials: observers could readily detect an object chasing another object, but not a line-end chasing another line-end, a line-end chasing an object, or an object chasing a line-end. We conclude that the underlying units of perceived animacy are discrete visual objects.

A customized bolus produced using a 3-dimensional printer for radiotherapy.

Directory of Open Access Journals (Sweden)

Shin-Wook Kim

Full Text Available OBJECTIVE: Boluses are used in high-energy radiotherapy in order to overcome the skin sparing effect. In practice though, commonly used flat boluses fail to make a perfect contact with the irregular surface of the patient's skin, resulting in air gaps. Hence, we fabricated a customized bolus using a 3-dimensional (3D printer and evaluated its feasibility for radiotherapy. METHODS: We designed two kinds of bolus for production on a 3D printer, one of which was the 3D printed flat bolus for the Blue water phantom and the other was a 3D printed customized bolus for the RANDO phantom. The 3D printed flat bolus was fabricated to verify its physical quality. The resulting 3D printed flat bolus was evaluated by assessing dosimetric parameters such as D1.5 cm, D5 cm, and D10 cm. The 3D printed customized bolus was then fabricated, and its quality and clinical feasibility were evaluated by visual inspection and by assessing dosimetric parameters such as Dmax, Dmin, Dmean, D90%, and V90%. RESULTS: The dosimetric parameters of the resulting 3D printed flat bolus showed that it was a useful dose escalating material, equivalent to a commercially available flat bolus. Analysis of the dosimetric parameters of the 3D printed customized bolus demonstrated that it is provided good dose escalation and good contact with the irregular surface of the RANDO phantom. CONCLUSIONS: A customized bolus produced using a 3D printer could potentially replace commercially available flat boluses.

A customized bolus produced using a 3-dimensional printer for radiotherapy.

Science.gov (United States)

Kim, Shin-Wook; Shin, Hun-Joo; Kay, Chul Seung; Son, Seok Hyun

2014-01-01

Boluses are used in high-energy radiotherapy in order to overcome the skin sparing effect. In practice though, commonly used flat boluses fail to make a perfect contact with the irregular surface of the patient's skin, resulting in air gaps. Hence, we fabricated a customized bolus using a 3-dimensional (3D) printer and evaluated its feasibility for radiotherapy. We designed two kinds of bolus for production on a 3D printer, one of which was the 3D printed flat bolus for the Blue water phantom and the other was a 3D printed customized bolus for the RANDO phantom. The 3D printed flat bolus was fabricated to verify its physical quality. The resulting 3D printed flat bolus was evaluated by assessing dosimetric parameters such as D1.5 cm, D5 cm, and D10 cm. The 3D printed customized bolus was then fabricated, and its quality and clinical feasibility were evaluated by visual inspection and by assessing dosimetric parameters such as Dmax, Dmin, Dmean, D90%, and V90%. The dosimetric parameters of the resulting 3D printed flat bolus showed that it was a useful dose escalating material, equivalent to a commercially available flat bolus. Analysis of the dosimetric parameters of the 3D printed customized bolus demonstrated that it is provided good dose escalation and good contact with the irregular surface of the RANDO phantom. A customized bolus produced using a 3D printer could potentially replace commercially available flat boluses.

Safe structural food bolus in elderly: the relevant parameters

OpenAIRE

Vandenberghe-Descamps, Mathilde; Septier, Chantal; Prot, Aurélie; Tournier, Carole; Hennequin, Martine; Vigneau, Evelyne; Feron, Gilles; Labouré, Hélène

2017-01-01

Mastication is essential to prepare food into a bolus ready to be swallowed safely, with no choking risk. Based on food bolus properties, a masticatory normative indicator was developed by Woda et al. (2010) to identify impaired masticatory function within good oral health population. The aim of the present study was to identify relevant parameters of bolus' structure to differentiate safe to unsafe bolus among elderly contrasting by their dental status.93 elderly, 58% with at least 7 posteri...

Knowing When to Stop: The Brain Mechanisms of Chasing Losses

DEFF Research Database (Denmark)

Campbell-Meiklejohn, Daniel; Woolrich, Mark; Passingham, Dick

2008-01-01

adult participants decided to chase losses or decided to quit gambling to prevent further losses.ResultsChasing losses was associated with increased activity in cortical areas linked to incentive-motivation and an expectation of reward. By contrast, quitting was associated with decreased activity...... in pathological gambling might involve a failure to appropriately balance activity within neural systems coding conflicting motivational states. Similar mechanisms might underlie the loss-of-control over appetitive behaviors in other impulse control disorders....

21 CFR 520.1660c - Oxytetracycline hydrochloride tablets/boluses.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Oxytetracycline hydrochloride tablets/boluses. 520....1660c Oxytetracycline hydrochloride tablets/boluses. (a) Specifications. Each tablet or bolus contains 250, 500, or 1,000 milligrams of oxytetracycline hydrochloride. (b) Sponsors. For sponsors in § 510...

SU-C-213-06: Dosimetric Verification of 3D Printed Electron Bolus

International Nuclear Information System (INIS)

Rasmussen, K; Corbett, M; Pelletier, C; Huang, Z; Feng, Y; Jung, J

2015-01-01

Purpose: To determine the dosimetric effect of 3D printed bolus in an anthropomorphic phantom. Methods: Conformable bolus material was generated for an anthropomorphic phantom from a DICOM volume. The bolus generated was a uniform expansion of 5mm applied to the nose region of the phantom, as this is a difficult area to uniformly apply bolus clinically. A Printrbot metal 3D Printer using PLA plastic generated the bolus. A 9MeV anterior beam with a 5cm cone was used to deliver dose to the nose of the phantom. TLD measurements were compared to predicted values at the phantom surface. Film planes were analyzed for the printed bolus, a standard 5mm bolus sheet placed on the phantom, and the phantom with no bolus applied to determine depth and dose distributions. Results: TLDs measured within 2.5% of predicted value for the 3D bolus. Film demonstrated a more uniform dose distribution in the nostril region for the 3d printed bolus than the standard bolus. This difference is caused by the air gap created around the nostrils by the standard bolus, creating a secondary build-up region. Both demonstrated a 50% central axis dose shift of 5mm relative to the no bolus film. HU for the bolus calculated the PLA electron density to be ∼1.1g/cc. Physical density was measured to be 1.3g/cc overall. Conclusion: 3D printed PLA bolus demonstrates improved dosimetric performance to standard bolus for electron beams with complex phantom geometry

SU-C-213-06: Dosimetric Verification of 3D Printed Electron Bolus

Energy Technology Data Exchange (ETDEWEB)

Rasmussen, K; Corbett, M; Pelletier, C; Huang, Z; Feng, Y; Jung, J [East Carolina Univ, Greenville, NC (United States)

2015-06-15

Purpose: To determine the dosimetric effect of 3D printed bolus in an anthropomorphic phantom. Methods: Conformable bolus material was generated for an anthropomorphic phantom from a DICOM volume. The bolus generated was a uniform expansion of 5mm applied to the nose region of the phantom, as this is a difficult area to uniformly apply bolus clinically. A Printrbot metal 3D Printer using PLA plastic generated the bolus. A 9MeV anterior beam with a 5cm cone was used to deliver dose to the nose of the phantom. TLD measurements were compared to predicted values at the phantom surface. Film planes were analyzed for the printed bolus, a standard 5mm bolus sheet placed on the phantom, and the phantom with no bolus applied to determine depth and dose distributions. Results: TLDs measured within 2.5% of predicted value for the 3D bolus. Film demonstrated a more uniform dose distribution in the nostril region for the 3d printed bolus than the standard bolus. This difference is caused by the air gap created around the nostrils by the standard bolus, creating a secondary build-up region. Both demonstrated a 50% central axis dose shift of 5mm relative to the no bolus film. HU for the bolus calculated the PLA electron density to be ∼1.1g/cc. Physical density was measured to be 1.3g/cc overall. Conclusion: 3D printed PLA bolus demonstrates improved dosimetric performance to standard bolus for electron beams with complex phantom geometry.

Effect of contrast media iodine concentration on bolus tracking

International Nuclear Information System (INIS)

Ishihara, Toshihiro; Hayashi, Takayuki; Nakaya, Yoshihiro; Naoi, Kuniji; Ikeno, Naoya; Kobayashi, Tatsushi; Satake, Mitsuo

2006-01-01

Computer-assisted bolus tracking has been confirmed to be a useful technique in computed tomography (CT) imaging and allows images to be captured with automated timing. The inflow of the contrast medium is monitored, and when the contrast medium reaches a predetermined level, CT image capture starts automatically. However, it has been shown that the preset threshold value of contrast medium is affected by its iodine concentration, which causes variations in image capture times. Greater speed in current multislice CT imaging requires that medical technicians pay more attention to setting the timing of image capture during venous examinations by taking into account the iodine concentration in contrast media. (author)

Chinese Learning Journeys: Chasing the Dream

Science.gov (United States)

Su, Feng, Ed.

2011-01-01

Eight students from mainland China chart their learning journeys across national and continental boundaries and socio-cultural contexts. The five women and three men structure their experiences of studying in China and the West around the turning points and life changing choices they made in chasing their dreams. They embody its emergent…

Correlations between aorto-popliteal bolus transit speed and aortic and popliteal bolus transit time during CT angiography of aortoiliac and lower extremity arteries

Energy Technology Data Exchange (ETDEWEB)

Nakaya, Yasuhiro, E-mail: y-nakaya@radiol.med.osaka-u.ac.jp [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita City, Osaka 565-0871 (Japan); Kim, Tonsok; Hori, Masatoshi; Onishi, Hiromitsu; Nakamoto, Atsushi; Tsuboyama, Takahiro; Maeda, Noboru; Higashihara, Hiroki; Tomoda, Kaname; Nakamura, Hironobu [Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita City, Osaka 565-0871 (Japan)

2011-08-15

Purpose: The purpose of this study was to investigate correlations between the aorto-popliteal bolus transit speed and aortic and popliteal bolus transit time in order to evaluate the possibility for prediction of bolus transit speed by single test injection technique. Materials and methods: Approval was obtained from our institutional review board for this study, which included 42 patients, from all of whom written informed consent was obtained. Low-dose serial CT scanning after injection of 12 ml contrast material (300 mg/ml) at a rate of 3 ml/s followed by saline flush was performed twice, first at the level of the upper abdomen and second at the level of the knee joint. The times needed to reach peak enhancement of the upper abdominal aorta (T-aorta) and bilateral popliteal arteries (T-popliteal) were obtained, and aorto-popliteal bolus transit speeds between the abdominal aorta and popliteal arteries were calculated. ABI was recorded for the bilateral feet. The Pearson's product-moment correlation coefficient was used to investigate the correlation between the bolus transit speed and T-aorta, T-popliteal, ABI, and patient age. Result: The respective correlation coefficients for bolus transit speed on the one hand and T-aorta, T-popliteal, ABI, patient age on the other were -0.50, -0.84, 0.36, and -0.52. Conclusion: The time to peak enhancement for popliteal arteries showed the strongest correlation with aorto-popliteal bolus transit speeds, and was considered to be the most accurate predictor for aorto-popliteal bolus transit speeds.

A Study on the Necessary Number of Bolus Treatments in Radiotherapy after Modified Radical Mastectomy

International Nuclear Information System (INIS)

Hong, Chae Seon; Kim, Jong Sik; Kim, Young Kon; Park, Young Hwan

2006-01-01

Post-mastectomy radiotherapy (PMR) is known to decrease loco-regional recurrence. Adequate skin and dermal dose are achieved by adding bolus. The more difficult clinical issue is determining the necessary number of bolus treatment, given the limits of normal skin tolerance. The aim of this study is to evaluate the necessary number of bolus treatment after PMR in patients with breast cancer. Four female breast cancer patients were included in the study. The median age was 53 years(range, 38-74), tumor were left sided in 2 patients and right sided in 2 patients. All patients were treated with postoperative radiotherapy after MRM. Radiotherapy was delivered to the chest wall (C.W) and supraclavicular lymph nodes (SCL) using 4 MV X-ray. The total dose was 50 Gy, in 2 Gy fractions (with 5 times a week). CT was performed for treatment planning, treatment planning was performed using A DAC-Pinnacles 3 (Phillips, USA) for all patients without and with bolus. Bolus treatment plans were generated using image tool (0.5 cm of thickness and 6 cm of width). Dose distribution was analyzed and the increased skin dose rate in the build-up region was computed and the skin dose using TLD-100 chips (Harshaw, USA) was measured. No significant difference was found in dose distribution without and with bolus; C.W coverage was 95-100% of the prescribed dose in both. But, there was remarkable difference in the skin dose to the scar. The skin dose to the scar without and with bolus were 100-105% and 50-75%. The increased skin dose rates in the build-up region for Pt. 1, Pt. 2. Pt. 3 and Pt. 4 were 23.3%, 35.6%, 34.9%, and 41.7%. The results of measured skin dose using TLD-100 chips in the cases without and with bolus were 209.3 cGy and 161.1 cGy, 200 cGy and 150.2 cGy, 211.4 cGy and 160.5 cGy, 198.6 cGy and 155.5 cGy for Pt. 1, Pt. 2, Pt. 3, and Pt. 4. It was concludes through this analysis that the adequate number of bolus treatments is 50-60% of the treatment program. Further, clinical

TU-H-CAMPUS-TeP1-05: Fast Processed 3D Printing-Aided Urethane Resin (PUR) Bolus in Radiation Therapy

Energy Technology Data Exchange (ETDEWEB)

Zhao, B; Chiu, T; Gu, X; Lee, H; Nedzi, L; Jiang, S [UT Southwestern Medical Center, Dallas, TX (United States)

2016-06-15

Purpose: 3D printed custom bolus is regularly used in radiation therapy clinic as a compensator. However, usual method of bolus printing with 100% filling is very time-consuming. The purpose of this study is to evaluate the feasibility and benefit of 3D printed bolus filled with UR. Methods: Two boluses were designed on nose (9e electrons) and ear (6× photons) for a head phantom in treatment planning system (TPS) to achieve dose coverage to the skin. The bolus structures (56–167cc) were converted to STereoLithographic (STL) model using an in-house developed algorithm and sent to a commercial fused deposition modeling (FDM) printer. Only shells were printed with polylactic acid (PLA) material. Liquid UR was then placed in a vacuum pump and slowly poured into the hollow bolus from its top opening. Liquid UR hardened in around half an hour. The phantom was rescanned with custom boluses attached and the dosimetry was compared with original design in TPS. Basic CT and dose properties were investigated. GaF films were irradiated to measure dose profile and output of several open photon and electron beams under solid water and UR slabs of same thicknesses. Results: CT number was 11.2±7.3 and 65.4±7.8, respectively for solid water(∼1.04g/cc) and UR(∼1.08g/cc). The output measurement at dmax for 6× was within 2% for the two materials. The relative dose profiles of the two materials above dmax show 94–99% Gamma analysis passing rates for both photons and electrons. Dose distributions with 3D PUR boluses maintained great coverage on the intended skin regions and resembled that with computer generated boluses. Manufacturing 3D PUR boluses was 3–4 times faster than 100% printed boluses. The efficiency significantly improves for larger boluses. Conclusion: The study suggests UR has similar dose responses as solid water. Making custom bolus with UR greatly increases clinical workflow efficiency.

TU-H-CAMPUS-TeP1-05: Fast Processed 3D Printing-Aided Urethane Resin (PUR) Bolus in Radiation Therapy

International Nuclear Information System (INIS)

Zhao, B; Chiu, T; Gu, X; Lee, H; Nedzi, L; Jiang, S

2016-01-01

Purpose: 3D printed custom bolus is regularly used in radiation therapy clinic as a compensator. However, usual method of bolus printing with 100% filling is very time-consuming. The purpose of this study is to evaluate the feasibility and benefit of 3D printed bolus filled with UR. Methods: Two boluses were designed on nose (9e electrons) and ear (6× photons) for a head phantom in treatment planning system (TPS) to achieve dose coverage to the skin. The bolus structures (56–167cc) were converted to STereoLithographic (STL) model using an in-house developed algorithm and sent to a commercial fused deposition modeling (FDM) printer. Only shells were printed with polylactic acid (PLA) material. Liquid UR was then placed in a vacuum pump and slowly poured into the hollow bolus from its top opening. Liquid UR hardened in around half an hour. The phantom was rescanned with custom boluses attached and the dosimetry was compared with original design in TPS. Basic CT and dose properties were investigated. GaF films were irradiated to measure dose profile and output of several open photon and electron beams under solid water and UR slabs of same thicknesses. Results: CT number was 11.2±7.3 and 65.4±7.8, respectively for solid water(∼1.04g/cc) and UR(∼1.08g/cc). The output measurement at dmax for 6× was within 2% for the two materials. The relative dose profiles of the two materials above dmax show 94–99% Gamma analysis passing rates for both photons and electrons. Dose distributions with 3D PUR boluses maintained great coverage on the intended skin regions and resembled that with computer generated boluses. Manufacturing 3D PUR boluses was 3–4 times faster than 100% printed boluses. The efficiency significantly improves for larger boluses. Conclusion: The study suggests UR has similar dose responses as solid water. Making custom bolus with UR greatly increases clinical workflow efficiency.

Split bolus technique in polytrauma: a prospective study on scan protocols for trauma analysis

NARCIS (Netherlands)

Beenen, Ludo F. M.; Sierink, Joanne C.; Kolkman, Saskia; Nio, C. Yung; Saltzherr, Teun Peter; Dijkgraaf, Marcel G. W.; Goslings, J. Carel

2015-01-01

For the evaluation of severely injured trauma patients a variety of total body computed tomography (CT) scanning protocols exist. Frequently multiple pass protocols are used. A split bolus contrast protocol can reduce the number of passes through the body, and thereby radiation exposure, in this

TU-F-CAMPUS-I-01: Investigation of the Effective Dose From Bolus Tracking Acquisitions at Different Anatomical Locations in the Chest for CT

Energy Technology Data Exchange (ETDEWEB)

Nowik, P; Bujila, R; Merzan, D [Dept. of Medical Physics, Karolinska University Hospital, Stockholm (Sweden)

2015-06-15

Purpose: Stationary table acquisitions (Bolus tracking) in X-ray Computed Tomography (CT) can Result in dose length products (DLP) comparable to spiral scans. It is today unclear whether or not the effective dose (E) for Bolus Tracking can be approximated using target region specific conversion factors (E/DLP). The purpose of this study was to investigate how E depends on the anatomical location of the Bolus Tracking in relation to Chest CT scans with the same DLP. Methods: Effective doses were approximated for the ICRP 110 adult Reference Male (AM) and adult Reference Female (FM) computational voxel phantoms using software for CT dose approximations (pre-simulated MC data). The effective dose was first approximated for a Chest CT scan using spiral technique and a CTDIvol (32 cm) of 6 mGy. The effective dose from the spiral scan was then compared to E approximated for contiguous Bolus Tracking acquisitions (1 cm separation), with a total collimation of 1 cm, over different locations of the chest of the voxel phantoms. The number of rotations used for the Bolus Tracking acquisitions was adjusted to yield the same DLP (32 cm) as the spiral scan. Results: Depending on the anatomical location of the Bolus Tracking, E ranged by factors of 1.3 to 6.8 for the AM phantom and 1.4 to 3.3 for the AF phantom, compared to the effective dose of the spiral scans. The greatest E for the Bolus Tracking acquisitions was observed for anatomical locations coinciding with breast tissue. This can be expected as breast tissue has a high tissue weighting factor in the calculation of E. Conclusion: For Chest CT scans, the effective dose from Bolus Tracking is highly dependent on the anatomical location where the scan is administered and will not always accurately be represented using target region specific conversion factors.

Esophageal Transit, Contraction and Perception of Transit After Swallows of Two Viscous Boluses.

Science.gov (United States)

Dalmazo, Jucileia; Aprile, Lilian Rose Otoboni; Dantas, Roberto Oliveira

2015-10-01

There have been results showing the influence of bolus viscosities and consistency on esophageal motility and transit. However, there is no description about the influence of two different viscous boluses on esophageal contractions, bolus transit and perception of transit. Our objective in this investigation was to evaluate the esophageal transit and contraction after swallows of two viscous boluses. By impedance and manometric methods, we measured the esophageal transit and contraction after swallows of two viscous boluses of 5 mL volume, 100% barium sulfate and yogurt, swallowed in duplicate in the supine and upright positions. The bolus transit, esophageal contractions and the perception of bolus transit through the esophagus were evaluated in both positions. Impedance and contraction were measured at 5, 10, 15 and 20 cm from the lower esophageal sphincter. After each swallow, the volunteers were asked about the sensation of bolus transit through the esophagus. In supine position, the yogurt had a less frequent complete bolus transit than barium. Also in the supine position, the esophageal transit was longer with yogurt than with barium. Esophageal contractions after swallows were similar between barium and yogurt boluses. There was no difference in perception of transit between the two boluses. Although both 100% barium sulfate and yogurt are viscous boluses and have similar viscosities, the transit through the esophagus is slower with yogurt bolus than with barium bolus, which suggests that viscosity may be not the sole factor to determine transit.

On bolus for megavoltage photon and electron radiation therapy

International Nuclear Information System (INIS)

Vyas, Vedang; Palmer, Lisa; Mudge, Ray; Jiang, Runqing; Fleck, Andre; Schaly, Bryan; Osei, Ernest; Charland, Paule

2013-01-01

Frequently, in radiation therapy one must treat superficial lesions on cancer patients; these are at or adjacent to the skin. Megavoltage photon radiotherapy penetrates through the skin to irradiate deep-seated tumors, with skin-sparing property. Hence, to treat superficial lesions, one must use a layer of scattering material to feign as the skin surface. Although megavoltage electron beams are used for superficial treatments, one occasionally needs to enhance the dose near the surface. Such is the function of a “bolus,” a natural or synthetically developed material that acts as a layer of tissue to provide a more effective treatment to the superficial lesions. Other uses of boluses are to correct for varying surface contours and to add scattering material around the patient's surface. Materials used as bolus vary from simple water to metal and include various mixtures and compounds. Even with the modernization of the technology for external-beam therapy and the emergence of various commercial boluses, the preparation and utilization of a bolus in clinical radiotherapy remains an art. Considering the varying experiences and practices, this paper briefly summarizes available boluses that have been proposed and are employed in clinical radiotherapy. Although this review is not exhaustive, it provides some initial guidance and answers questions that may arise in clinical practice

Pattern production through a chiral chasing mechanism

Science.gov (United States)

Woolley, Thomas E.

2017-09-01

Recent experiments on zebrafish pigmentation suggests that their typical black and white striped skin pattern is made up of a number of interacting chromatophore families. Specifically, two of these cell families have been shown to interact through a nonlocal chasing mechanism, which has previously been modeled using integro-differential equations. We extend this framework to include the experimentally observed fact that the cells often exhibit chiral movement, in that the cells chase, and run away, at angles different to the line connecting their centers. This framework is simplified through the use of multiple small limits leading to a coupled set of partial differential equations which are amenable to Fourier analysis. This analysis results in the production of dispersion relations and necessary conditions for a patterning instability to occur. Beyond the theoretical development and the production of new pattern planiforms we are able to corroborate the experimental hypothesis that the global pigmentation patterns can be dependent on the chirality of the chromatophores.

Modeling the retention of rumen boluses for the electronic identification of goats.

Science.gov (United States)

Carné, S; Caja, G; Ghirardi, J J; Salama, A A K

2011-02-01

We constructed a regression model to estimate the retention of electronic boluses in goats. With this aim, 2,482 boluses were administered to goats from dairy (Murciano-Granadina, n=1,326; French Alpine, n=381) and meat (Blanca de Rasquera, n=532) breeds. A total of 19 bolus types made of materials (ceramic, plastic tubes filled with concrete or silicone, and ballasts) differing in their specific gravity (SG) were used, thereby obtaining a wide variation in bolus features: diameter (9 to 22 mm), length (37 to 84 mm), weight (5 to 111 g), volume (2.6 to 26 mL), and SG (1.0 to 5.5). Each bolus contained a half-duplex glass encapsulated transponder (32 × 3.8mm) and was administered using adapted balling guns. Murciano-Granadina and Blanca de Rasquera goats also wore 2 visual plastic ear tags: V1 (double flag, 5.1g) and V2 (flag-button, 4.2g). No data on ear tags in French Alpine goats was available. Bolus and ear tag retention [(retained/monitored) × 100] was recorded for at least 1 yr. Dynamic reading efficiency [(dynamic reading/static reading) × 100] was also evaluated from 1,496 bolus readings. No administration incidences or apparent negative behavior or performance effects were observed for any bolus type. Static reading efficiency of retained boluses was 100%, except for the prototypes with metal ballasts, which yielded a 93.3% reading efficiency. Retention of metal-ballasted boluses was confirmed using x-ray equipment. Excluding ballasted boluses, a 99.5% dynamic reading efficiency was obtained. Ear tag losses were 6.5% for V1 and 3.7% for V2, ranging from 3.2 to 7.8% depending on ear tag type and goat breed. Bolus retention varied (0 to 100%) according to their physical features. Obtained data allowed the fitting of a logistic model of bolus retention rate according to bolus volume and weight (R(2) = 0.98); the SG was implicitly considered. Estimated weight and SG to produce medium- (15 mL) and standard-sized (22 mL) boluses for 99.95% retention rate in

Intravenous Tranexamic Acid Bolus plus Infusion Is Not More Effective than a Single Bolus in Primary Hip Arthroplasty: A Randomized Controlled Trial.

Science.gov (United States)

Zufferey, Paul J; Lanoiselée, Julien; Chapelle, Céline; Borisov, Dmitry B; Bien, Jean-Yves; Lambert, Pierre; Philippot, Rémi; Molliex, Serge; Delavenne, Xavier

2017-09-01

Preoperative administration of the antifibrinolytic agent tranexamic acid reduces bleeding in patients undergoing hip arthroplasty. Increased fibrinolytic activity is maintained throughout the first day postoperation. The objective of the study was to determine whether additional perioperative administration of tranexamic acid would further reduce blood loss. This prospective, double-blind, parallel-arm, randomized, superiority study was conducted in 168 patients undergoing unilateral primary hip arthroplasty. Patients received a preoperative intravenous bolus of 1 g of tranexamic acid followed by a continuous infusion of either tranexamic acid 1 g (bolus-plus-infusion group) or placebo (bolus group) for 8 h. The primary outcome was calculated perioperative blood loss up to day 5. Erythrocyte transfusion was implemented according to a restrictive transfusion trigger strategy. The mean perioperative blood loss was 919 ± 338 ml in the bolus-plus-infusion group (84 patients analyzed) and 888 ± 366 ml in the bolus group (83 patients analyzed); mean difference, 30 ml (95% CI, -77 to 137; P = 0.58). Within 6 weeks postsurgery, three patients in each group (3.6%) underwent erythrocyte transfusion and two patients in the bolus group experienced distal deep-vein thrombosis. A meta-analysis combining data from this study with those of five other trials showed no incremental efficacy of additional perioperative administration of tranexamic acid. A preoperative bolus of tranexamic acid, associated with a restrictive transfusion trigger strategy, resulted in low erythrocyte transfusion rates in patients undergoing hip arthroplasty. Supplementary perioperative administration of tranexamic acid did not achieve any further reduction in blood loss.

Role of physical bolus properties as sensory inputs in the trigger of swallowing.

Science.gov (United States)

Peyron, Marie-Agnès; Gierczynski, Isabelle; Hartmann, Christoph; Loret, Chrystel; Dardevet, Dominique; Martin, Nathalie; Woda, Alain

2011-01-01

Swallowing is triggered when a food bolus being prepared by mastication has reached a defined state. However, although this view is consensual and well supported, the physical properties of the swallowable bolus have been under-researched. We tested the hypothesis that measuring bolus physical changes during the masticatory sequence to deglutition would reveal the bolus properties potentially involved in swallowing initiation. Twenty normo-dentate young adults were instructed to chew portions of cereal and spit out the boluses at different times in the masticatory sequence. The mechanical properties of the collected boluses were measured by a texture profile analysis test currently used in food science. The median particle size of the boluses was evaluated by sieving. In a simultaneous sensory study, twenty-five other subjects expressed their perception of bolus texture dominating at any mastication time. Several physical changes appeared in the food bolus as it was formed during mastication: (1) in rheological terms, bolus hardness rapidly decreased as the masticatory sequence progressed, (2) by contrast, adhesiveness, springiness and cohesiveness regularly increased until the time of swallowing, (3) median particle size, indicating the bolus particle size distribution, decreased mostly during the first third of the masticatory sequence, (4) except for hardness, the rheological changes still appeared in the boluses collected just before swallowing, and (5) physical changes occurred, with sensory stickiness being described by the subjects as a dominant perception of the bolus at the end of mastication. Although these physical and sensory changes progressed in the course of mastication, those observed just before swallowing seem to be involved in swallowing initiation. They can be considered as strong candidates for sensory inputs from the bolus that are probably crucially involved in the triggering of swallowing, since they appeared in boluses prepared in various

Role of physical bolus properties as sensory inputs in the trigger of swallowing.

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Marie-Agnès Peyron

Full Text Available BACKGROUND: Swallowing is triggered when a food bolus being prepared by mastication has reached a defined state. However, although this view is consensual and well supported, the physical properties of the swallowable bolus have been under-researched. We tested the hypothesis that measuring bolus physical changes during the masticatory sequence to deglutition would reveal the bolus properties potentially involved in swallowing initiation. METHODS: Twenty normo-dentate young adults were instructed to chew portions of cereal and spit out the boluses at different times in the masticatory sequence. The mechanical properties of the collected boluses were measured by a texture profile analysis test currently used in food science. The median particle size of the boluses was evaluated by sieving. In a simultaneous sensory study, twenty-five other subjects expressed their perception of bolus texture dominating at any mastication time. FINDINGS: Several physical changes appeared in the food bolus as it was formed during mastication: (1 in rheological terms, bolus hardness rapidly decreased as the masticatory sequence progressed, (2 by contrast, adhesiveness, springiness and cohesiveness regularly increased until the time of swallowing, (3 median particle size, indicating the bolus particle size distribution, decreased mostly during the first third of the masticatory sequence, (4 except for hardness, the rheological changes still appeared in the boluses collected just before swallowing, and (5 physical changes occurred, with sensory stickiness being described by the subjects as a dominant perception of the bolus at the end of mastication. CONCLUSIONS: Although these physical and sensory changes progressed in the course of mastication, those observed just before swallowing seem to be involved in swallowing initiation. They can be considered as strong candidates for sensory inputs from the bolus that are probably crucially involved in the triggering of

Optimization of a beam shaping bolus for superficial microwave hyperthermia waveguide applicators using a finite element method

International Nuclear Information System (INIS)

Kumaradas, J Carl; Sherar, Michael D

2003-01-01

Temperature inhomogeneity in hyperthermia treatments often limits the total thermal dose that can be delivered to the tumour region. To reduce such inhomogeneities, a prototype dynamically modifiable square array of saline-filled patches which attenuate microwave energy was developed for superficial treatments that use external microwave applicators. The array was situated inside the coupling water bolus that is often used with external applicators. The prototype has been previously tested clinically with promising results. A more complete theoretical analysis of the performance of this new bolus design and improvements to its design by modelling are presented here. The analysis was performed by performing five iterative simulations of the SAR pattern produced inside a tissue structure by a waveguide applicator with a water bolus containing the dynamic patch array attached. Between iterations the patch array configuration was modified in an attempt to improve the ability of the bolus to confine heating to an 'L'-shaped tumour region. These simulations were performed using the finite element method. The steady-state temperature profile was then computed using a finite element method based simulation of heat transfer that assumed a given applicator power level and water bolus temperature. Several iterations of these heat transfer simulations were performed with varying applicator power level and water bolus temperature to improve the confinement of heating to the target region. The analysis showed that the dynamic patch array should be capable of conforming heating to an 'L'-shaped target tumour region while limiting the heating to the surrounding normal tissue to an acceptable level

Bolus obstruction by Ascaris lumbricoides | Wynne | South African ...

African Journals Online (AJOL)

Bolus obstruction by Ascaris lumbricoides. J.M. Wynne, B.A.H. Ellman. Abstract. Seventy-three cases of obstruction due to a bolus of Ascaris worms are reviewed, The diagnosis was made on the basis either of a characteristic palpable mass or a characteristic radiographic appearance. In 67 cases conservative treatment ...

Solid bolus swallowing in the radiologic evaluation of dysphagia

International Nuclear Information System (INIS)

Westen, D. van; Ekberg, O.

1993-01-01

Patients with dysphagia, heartburn and chest pain are regularly referred for radiologic evaluation of swallowing. The liquid barium swallow has been of great value for the biphasic evaluation of the pharynx and esophagus. Though many patients complain of dysphagia specifically for solids, solid bolus swallow is ususally not part of the evaluation. For the present study we therefore included the use of a solid bolus with a diameter of 13 mm and interviewed the patients carefully for any symptoms during this tablet swallow. Of 200 patients examined, the tablet passed through the esophagus without delay in 102. In the 98 patients with delayed passage, the solid bolus arrest occurred in the pharynx in 5 and in the esophagus in 93. Arrest in the esophagus was due to esophageal dysmotility in 48 patients. Twenty of these were symptomatic during the tablet swallow. A narrowing was the cause in 45, of whom 9 had symptoms. In 18 patients (9%) the solid bolus added key information to the radiologic evaluation. We therefore recommend that the solid bolus is included in the routine radiologic work-up of patients with dysphagia. Careful attention to symptoms during the tablet swallow is important. (orig.)

Solid bolus swallowing in the radiologic evaluation of dysphagia

Energy Technology Data Exchange (ETDEWEB)

Westen, D. van (Dept. of Diagnostic Radiology, Malmoe General Hospital, Univ. Lund (Sweden)); Ekberg, O. (Dept. of Diagnostic Radiology, Malmoe General Hospital, Univ. Lund (Sweden))

1993-07-01

Patients with dysphagia, heartburn and chest pain are regularly referred for radiologic evaluation of swallowing. The liquid barium swallow has been of great value for the biphasic evaluation of the pharynx and esophagus. Though many patients complain of dysphagia specifically for solids, solid bolus swallow is ususally not part of the evaluation. For the present study we therefore included the use of a solid bolus with a diameter of 13 mm and interviewed the patients carefully for any symptoms during this tablet swallow. Of 200 patients examined, the tablet passed through the esophagus without delay in 102. In the 98 patients with delayed passage, the solid bolus arrest occurred in the pharynx in 5 and in the esophagus in 93. Arrest in the esophagus was due to esophageal dysmotility in 48 patients. Twenty of these were symptomatic during the tablet swallow. A narrowing was the cause in 45, of whom 9 had symptoms. In 18 patients (9%) the solid bolus added key information to the radiologic evaluation. We therefore recommend that the solid bolus is included in the routine radiologic work-up of patients with dysphagia. Careful attention to symptoms during the tablet swallow is important. (orig.).

A mathematical model for the movement of food bolus of varying viscosities through the esophagus

Science.gov (United States)

Tripathi, Dharmendra

2011-09-01

This mathematical model is designed to study the influence of viscosity on swallowing of food bolus through the esophagus. Food bolus is considered as viscous fluid with variable viscosity. Geometry of esophagus is assumed as finite length channel and flow is induced by peristaltic wave along the length of channel walls. The expressions for axial velocity, transverse velocity, pressure gradient, volume flow rate and stream function are obtained under the assumptions of long wavelength and low Reynolds number. The impacts of viscosity parameter on pressure distribution, local wall shear stress, mechanical efficiency and trapping are numerically discussed with the help of computational results. On the basis of presented study, it is revealed that swallowing of low viscous fluids through esophagus requires less effort in comparison to fluids of higher viscosity. This result is similar to the experimental result obtained by Raut et al. [1], Dodds [2] and Ren et al. [3]. It is further concluded that the pumping efficiency increases while size of trapped bolus reduces when viscosity of fluid is high.

Safety and efficacy of Bolus administration of magnesium sulphate ...

African Journals Online (AJOL)

Safety and efficacy of Bolus administration of magnesium sulphate for preeclampsia. ... On-going research is addressing its administration in terms of dosage, duration and safety. Objective: We evaluated a ... Keywords: safety, efficacy, bolus magnesium sulphate, preeclampsia, University of Benin Teaching Hospital

SWFSC/MMTD/ETP: Chase Encirclement Stress Studies (CHESS) 2001

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The CHase Encirclement Stress Studies (CHESS) are part of a comprehensive research program designed to investigate the status of dolphin stocks that are involved in...

Accuracy of pencil-beam redefinition algorithm dose calculations in patient-like cylindrical phantoms for bolus electron conformal therapy.

Science.gov (United States)

Carver, Robert L; Hogstrom, Kenneth R; Chu, Connel; Fields, Robert S; Sprunger, Conrad P

2013-07-01

The purpose of this study was to document the improved accuracy of the pencil beam redefinition algorithm (PBRA) compared to the pencil beam algorithm (PBA) for bolus electron conformal therapy using cylindrical patient phantoms based on patient computed tomography (CT) scans of retromolar trigone and nose cancer. PBRA and PBA electron dose calculations were compared with measured dose in retromolar trigone and nose phantoms both with and without bolus. For the bolus treatment plans, a radiation oncologist outlined a planning target volume (PTV) on the central axis slice of the CT scan for each phantom. A bolus was designed using the planning.decimal(®) (p.d) software (.decimal, Inc., Sanford, FL) to conform the 90% dose line to the distal surface of the PTV. Dose measurements were taken with thermoluminescent dosimeters placed into predrilled holes. The Pinnacle(3) (Philips Healthcare, Andover, MD) treatment planning system was used to calculate PBA dose distributions. The PBRA dose distributions were calculated with an in-house C++ program. In order to accurately account for the phantom materials a table correlating CT number to relative electron stopping and scattering powers was compiled and used for both PBA and PBRA dose calculations. Accuracy was determined by comparing differences in measured and calculated dose, as well as distance to agreement for each measurement point. The measured doses had an average precision of 0.9%. For the retromolar trigone phantom, the PBRA dose calculations had an average ± 1σ dose difference (calculated - measured) of -0.65% ± 1.62% without the bolus and -0.20% ± 1.54% with the bolus. The PBA dose calculation had an average dose difference of 0.19% ± 3.27% without the bolus and -0.05% ± 3.14% with the bolus. For the nose phantom, the PBRA dose calculations had an average dose difference of 0.50% ± 3.06% without bolus and -0.18% ± 1.22% with the bolus. The PBA dose calculations had an average dose difference of 0.65% �

Open-loop glucose control: Automatic IOB-based super-bolus feature for commercial insulin pumps.

Science.gov (United States)

Rosales, Nicolás; De Battista, Hernán; Vehí, Josep; Garelli, Fabricio

2018-06-01

Although there has been significant progress towards closed-loop type 1 diabetes mellitus (T1DM) treatments, most diabetic patients still treat this metabolic disorder in an open-loop manner, based on insulin pump therapy (basal and bolus insulin infusion). This paper presents a method for automatic insulin bolus shaping based on insulin-on-board (IOB) as an alternative to conventional bolus dosing. The methodology presented allows the pump to generate the so-called super-bolus (SB) employing a two-compartment IOB dynamic model. The extra amount of insulin to boost the bolus and the basal cutoff time are computed using the duration of insulin action (DIA). In this way, the pump automatically re-establishes basal insulin when IOB reaches its basal level. Thus, detrimental transients caused by manual or a-priori computations are avoided. The potential of this method is illustrated via in-silico trials over a 30 patients cohort in single meal and single day scenarios. In the first ones, improvements were found (standard treatment vs. automatic SB) both in percentage time in euglycemia (75g meal: 81.9 ± 15.59 vs. 89.51 ± 11.95, ρ ≃ 0; 100g meal: 75.12 ± 18.23 vs. 85.46 ± 14.96, ρ ≃ 0) and time in hypoglecymia (75g meal: 5.92 ± 14.48 vs. 0.97 ± 4.15, ρ=0.008; 100g meal: 9.5 ± 17.02 vs. 1.85 ± 7.05, ρ=0.014). In a single day scenario, considering intra-patient variability, the time in hypoglycemia was reduced (9.57 ± 14.48 vs. 4.21 ± 6.18, ρ=0.028) and improved the time in euglycemia (79.46 ± 17.46 vs. 86.29 ± 11.73, ρ=0.007). The automatic IOB-based SB has the potential of a better performance in comparison with the standard treatment, particularly for high glycemic index meals with high carbohydrate content. Both glucose excursion and time spent in hypoglycemia were reduced. Copyright © 2018 Elsevier B.V. All rights reserved.

Association between swallow perception and esophageal bolus clearance in patients with globus sensation.

Science.gov (United States)

Chen, Chien-Lin; Yi, Chih-Hsun; Liu, Tso-Tsai

2013-04-01

Globus sensation is common, but its pathogenesis is not yet clear. Our purpose was to investigate subjective perception of swallowing and esophageal motility by combined multichannel intraluminal impedance and manometry (MII-EM) for patients with globus sensation. Combined MII-EM was performed for 25 globus patients and 15 healthy controls. Swallows were abnormal if hypocontractivity or simultaneous contractions occurred. Esophageal bolus transit was incomplete if bolus exit was not found at one or more of all measurement sites. Perception of each swallow was assessed by use of a standardized scoring system, and was enhanced if the score was >1. Few globus patients reported enhanced perception during viscous or solid swallows. Incomplete bolus transit and enhanced perception occurred similarly between viscous and solid boluses. Agreement between enhanced perception and proximal bolus clearance was greater during solid swallows (κ = 0.45, 95 % CI: 0.32-0.58) than during viscous swallows (κ = 0.13, 95 % CI: 0-0.25) (P perception and total bolus clearance was greater during solid swallows (κ = 0.46, 95 % CI: 0.34-0.58) than during viscous swallows (κ = 0.11, 95 % CI: 0-0.22) (P perception is uncommon in patients with globus sensation, although there is a significant association between enhanced esophageal perception and solid bolus clearance. Application of a solid bolus may help better delineation of the interrelationship between the subjective perception of bolus passage and the objective measurement of bolus clearance.

Establishment of the Fox Chase Network Breast Cancer Risk Registry

National Research Council Canada - National Science Library

Daly, Mary

1997-01-01

.... The development of the Fox Chase Cancer Center Breast Cancer Risk Registry was proposed to facilitate research in the epidemiologic and genetic predictors of disease and will permit evaluation...

Bolus obstruction by Ascaris lumbricoides

African Journals Online (AJOL)

In 67 cases conservative treatment was successful. ... bolus of worms, biliary ascariasis,3.6 pancreatitis and acute ... or chronic granulomatous peritonitis is rare.i These complica- ... obstruction admitted to the paediatric surgical wards of the.

Efficacy of a Targeted Drug Delivery on-Demand Bolus Option for Chronic Pain.

Science.gov (United States)

Bolash, Robert B; Niazi, Tariq; Kumari, Meera; Azer, Gerges; Mekhail, Nagy

2018-03-01

Intrathecal targeted drug delivery systems historically required physician office visits for dose adjustment to manage fluctuating pain. A wireless device now enables patients to supplement their basal intrathecal infusion with a programmed on-demand bolus dose. We sought to quantify the change in oral breakthrough opioid need associated with the use of an intrathecal bolus in comparison to those treated with the basal infusion alone. Demographic, dosage, bolus usage and longevity data were extracted from the historical medical record of 69 patients (18/51 bolus/nonbolus) followed continuously at our center. Medication consumption and Pain Disability Index measures were obtained at baseline and most recent follow-up. Among patients with the bolus option, only 2 (11%; confidence interval [CI] 0% to 26%) continued to require oral opiates to manage breakthrough pain compared to 29 (57%; CI 43% to 71%) without the bolus option. The Pain Disability Index score decreased by 19% in patients with the bolus option and by 25% in those with the basal infusion. Total daily intrathecal opioid intake was 34% lower in the group with the bolus device. Utilizing an intrathecal bolus to treat incident pain was a safe way to manage unpredictable breakthrough pain and may represent a cost-saving opportunity by eliminating the need for oral analgesic medications. © 2017 World Institute of Pain.

Collective chasing behavior between cooperators and defectors in the spatial prisoner's dilemma.

Directory of Open Access Journals (Sweden)

Genki Ichinose

Full Text Available Cooperation is one of the essential factors for all biological organisms in major evolutionary transitions. Recent studies have investigated the effect of migration for the evolution of cooperation. However, little is known about whether and how an individuals' cooperativeness coevolves with mobility. One possibility is that mobility enhances cooperation by enabling cooperators to escape from defectors and form clusters; the other possibility is that mobility inhibits cooperation by helping the defectors to catch and exploit the groups of cooperators. In this study we investigate the coevolutionary dynamics by using the prisoner's dilemma game model on a lattice structure. The computer simulations demonstrate that natural selection maintains cooperation in the form of evolutionary chasing between the cooperators and defectors. First, cooperative groups grow and collectively move in the same direction. Then, mutant defectors emerge and invade the cooperative groups, after which the defectors exploit the cooperators. Then other cooperative groups emerge due to mutation and the cycle is repeated. Here, it is worth noting that, as a result of natural selection, the mobility evolves towards directional migration, but not to random or completely fixed migration. Furthermore, with directional migration, the rate of global population extinction is lower when compared with other cases without the evolution of mobility (i.e., when mobility is preset to random or fixed. These findings illustrate the coevolutionary dynamics of cooperation and mobility through the directional chasing between cooperators and defectors.

The predictive ability of six pharmacokinetic models of rocuronium developed using a single bolus: evaluation with bolus and continuous infusion regimen.

Science.gov (United States)

Sasakawa, Tomoki; Masui, Kenichi; Kazama, Tomiei; Iwasaki, Hiroshi

2016-08-01

Rocuronium concentration prediction using pharmacokinetic (PK) models would be useful for controlling rocuronium effects because neuromuscular monitoring throughout anesthesia can be difficult. This study assessed whether six different compartmental PK models developed from data obtained after bolus administration only could predict the measured plasma concentration (Cp) values of rocuronium delivered by bolus followed by continuous infusion. Rocuronium Cp values from 19 healthy subjects who received a bolus dose followed by continuous infusion in a phase III multicenter trial in Japan were used retrospectively as evaluation datasets. Six different compartmental PK models of rocuronium were used to simulate rocuronium Cp time course values, which were compared with measured Cp values. Prediction error (PE) derivatives of median absolute PE (MDAPE), median PE (MDPE), wobble, divergence absolute PE, and divergence PE were used to assess inaccuracy, bias, intra-individual variability, and time-related trends in APE and PE values. MDAPE and MDPE values were acceptable only for the Magorian and Kleijn models. The divergence PE value for the Kleijn model was lower than -10 %/h, indicating unstable prediction over time. The Szenohradszky model had the lowest divergence PE (-2.7 %/h) and wobble (5.4 %) values with negative bias (MDPE = -25.9 %). These three models were developed using the mixed-effects modeling approach. The Magorian model showed the best PE derivatives among the models assessed. A PK model developed from data obtained after single-bolus dosing can predict Cp values during bolus and continuous infusion. Thus, a mixed-effects modeling approach may be preferable in extrapolating such data.

Analysis of factors influencing the integrated bolus peak timing in contrast-enhanced brain computed tomographic angiography

International Nuclear Information System (INIS)

Son, Soon Yong; Choi, Kwan Woo; Jeong, Hoi Woun; Jang, Seo Goo; Jung, Jae Young; Yun, Jung Soo; Kim, Ki Won; Lee, Young Ah; Son, Jin Hyun; Min, Jung Whan

2016-01-01

The objective of this study was to analyze the factors influencing integrated bolus peak timing in contrast- enhanced computed tomographic angiography (CTA) and to determine a method of calculating personal peak time. The optimal time was calculated by performing multiple linear regression analysis, after finding the influence factors through correlation analysis between integrated peak time of contrast medium and personal measured value by monitoring CTA scans. The radiation exposure dose in CTA was 716.53 mGy·cm and the radiation exposure dose in monitoring scan was 15.52 mGy (2 - 34 mGy). The results were statistically significant (p < .01). Regression analysis revealed, a -0.160 times decrease with a one-step increase in heart rate in male, and -0.004, -0.174, and 0.006 times decrease with one-step in DBP, heart rate, and blood sugar, respectively, in female. In a consistency test of peak time by calculating measured peak time and peak time by using the regression equation, the consistency was determined to be very high for male and female. This study could prevent unnecessary dose exposure by encouraging in clinic calculation of personal integrated peak time of contrast medium prior to examination

78 FR 69663 - Jonathan and Jayne Chase Troy Mills Hydroelectric Inc.; Notice of Transfer of Exemption

Science.gov (United States)

2013-11-20

... Jayne Chase Troy Mills Hydroelectric Inc.; Notice of Transfer of Exemption 1. By letter filed October 15, 2013, Jonathan Chase informed the Commission that the exemption from licensing for the Troy Hydroelectric Project, FERC No. 13381, originally issued December 2, 2011,\\1\\ has been transferred to Troy Mills...

An Adaptive Nonlinear Basal-Bolus Calculator for Patients With Type 1 Diabetes

DEFF Research Database (Denmark)

Boiroux, Dimitri; Aradóttir, Tinna Björk; Nørgaard, Kirsten

2017-01-01

size. Following meal announcements, the meal compartment and the meal time constant are estimated, otherwise insulin sensitivity is estimated. Results : We compare the performance of a conventional linear bolus calculator with the proposed bolus calculator. The proposed basal-bolus calculator......Background : Bolus calculators help patients with type 1 diabetes to mitigate the effect of meals on their blood glucose by administering a large amount of insulin at mealtime. Intraindividual changes in patients physiology and nonlinearity in insulin-glucose dynamics pose a challenge...... glucose monitor (CGM). The basal rate is determined by calculating the steady state of the model and is adjusted once a day before breakfast. The bolus size is determined by optimizing the postprandial glucose values based on an estimate of the insulin sensitivity and states, as well as the announced meal...

The influence of a solid and liquid bolus on food-stimulated gastroesophageal reflux

Energy Technology Data Exchange (ETDEWEB)

Naeser, A.; Behrens, J.K.; Vejen-Christiansen, L.; Funch-Jensen, P.; Thommesen, P. (Aarhus Kommunehospital (Denmark). GI Motility Lab. Aarhus Kommunehospital (Denmark). Dept. of Diagnostic Radiology R)

1992-02-01

Using a radiological method to demonstrate food-stimulated gastroesophageal reflux (GER), a comparative study was carried out employing a solid, already validated bolus versus a liquid one. One hundred and four consecutive patients received both a solid and a liquid bolus in randomized order. GER was observed in 37 (35.6%) patients receiving the solid bolus versus 28 (26.9%) with the liquid one. This means that the solid bolus provokes significantly more reflux (P<0.02). GER, grade II (reflux above the level of the carina), occurred equally often as a result of both types of bolus, however. The study suggests that significant, food-stimulated GER is independent of the consistency of the foodstuffs and may be detected employing a liquid bolus. This result might be used in the examination of infants for GER, using milk as a food stimulus. (orig.).

The influence of a solid and liquid bolus on food-stimulated gastroesophageal reflux

International Nuclear Information System (INIS)

Naeser, A.; Behrens, J.K.; Vejen-Christiansen, L.; Funch-Jensen, P.; Thommesen, P.; Aarhus Kommunehospital

1992-01-01

Using a radiological method to demonstrate food-stimulated gastroesophageal reflux (GER), a comparative study was carried out employing a solid, already validated bolus versus a liquid one. One hundred and four consecutive patients received both a solid and a liquid bolus in randomized order. GER was observed in 37 (35.6%) patients receiving the solid bolus versus 28 (26.9%) with the liquid one. This means that the solid bolus provokes significantly more reflux (P [de

Cheetahs, Acinonyx jubatus, balance turn capacity with pace when chasing prey

Science.gov (United States)

Wilson, John W.; Mills, Michael G. L.; Wilson, Rory P.; Peters, Gerrit; Mills, Margaret E. J.; Speakman, John R.; Durant, Sarah M.; Bennett, Nigel C.; Marks, Nikki J.; Scantlebury, Michael

2013-01-01

Predator–prey interactions are fundamental in the evolution and structure of ecological communities. Our understanding, however, of the strategies used in pursuit and evasion remains limited. Here, we report on the hunting dynamics of the world's fastest land animal, the cheetah, Acinonyx jubatus. Using miniaturized data loggers, we recorded fine-scale movement, speed and acceleration of free-ranging cheetahs to measure how hunting dynamics relate to chasing different sized prey. Cheetahs attained hunting speeds of up to 18.94 m s−1 and accelerated up to 7.5 m s−2 with greatest angular velocities achieved during the terminal phase of the hunt. The interplay between forward and lateral acceleration during chases showed that the total forces involved in speed changes and turning were approximately constant over time but varied with prey type. Thus, rather than a simple maximum speed chase, cheetahs first accelerate to decrease the distance to their prey, before reducing speed 5–8 s from the end of the hunt, so as to facilitate rapid turns to match prey escape tactics, varying the precise strategy according to prey species. Predator and prey thus pit a fine balance of speed against manoeuvring capability in a race for survival. PMID:24004493

Cheetahs, Acinonyx jubatus, balance turn capacity with pace when chasing prey.

Science.gov (United States)

Wilson, John W; Mills, Michael G L; Wilson, Rory P; Peters, Gerrit; Mills, Margaret E J; Speakman, John R; Durant, Sarah M; Bennett, Nigel C; Marks, Nikki J; Scantlebury, Michael

2013-10-23

Predator-prey interactions are fundamental in the evolution and structure of ecological communities. Our understanding, however, of the strategies used in pursuit and evasion remains limited. Here, we report on the hunting dynamics of the world's fastest land animal, the cheetah, Acinonyx jubatus. Using miniaturized data loggers, we recorded fine-scale movement, speed and acceleration of free-ranging cheetahs to measure how hunting dynamics relate to chasing different sized prey. Cheetahs attained hunting speeds of up to 18.94 m s(-1) and accelerated up to 7.5 m s(-2) with greatest angular velocities achieved during the terminal phase of the hunt. The interplay between forward and lateral acceleration during chases showed that the total forces involved in speed changes and turning were approximately constant over time but varied with prey type. Thus, rather than a simple maximum speed chase, cheetahs first accelerate to decrease the distance to their prey, before reducing speed 5-8 s from the end of the hunt, so as to facilitate rapid turns to match prey escape tactics, varying the precise strategy according to prey species. Predator and prey thus pit a fine balance of speed against manoeuvring capability in a race for survival.

MO-H-19A-03: Patient Specific Bolus with 3D Printing Technology for Electron Radiotherapy

International Nuclear Information System (INIS)

Zou, W; Swann, B; Siderits, R; McKenna, M; Khan, A; Yue, N; Zhang, M; Fisher, T

2014-01-01

Purpose: Bolus is widely used in electron radiotherapy to achieve desired dose distribution. 3D printing technologies provide clinicians with easy access to fabricate patient specific bolus accommodating patient body surface irregularities and tissue inhomogeneity. This study presents the design and the clinical workflow of 3D printed bolus for patient electron therapy in our clinic. Methods: Patient simulation CT images free of bolus were exported from treatment planning system (TPS) to an in-house developed software package. Bolus with known material properties was designed in the software package and then exported back to the TPS as a structure. Dose calculation was carried out to examine the coverage of the target. After satisfying dose distribution was achieved, the bolus structure was transferred in Standard Tessellation Language (STL) file format for the 3D printer to generate the machine codes for printing. Upon receiving printed bolus, a quick quality assurance was performed with patient resimulated with bolus in place to verify the bolus dosimetric property before treatment started. Results: A patient specific bolus for electron radiotherapy was designed and fabricated in Form 1 3D printer with methacrylate photopolymer resin. Satisfying dose distribution was achieved in patient with bolus setup. Treatment was successfully finished for one patient with the 3D printed bolus. Conclusion: The electron bolus fabrication with 3D printing technology was successfully implemented in clinic practice

MO-H-19A-03: Patient Specific Bolus with 3D Printing Technology for Electron Radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Zou, W; Swann, B; Siderits, R; McKenna, M; Khan, A; Yue, N; Zhang, M [Rutgers University, New Brunswick, NJ (United States); Fisher, T [Memorial Medical Center, Modesto, CA (United States)

2014-06-15

Purpose: Bolus is widely used in electron radiotherapy to achieve desired dose distribution. 3D printing technologies provide clinicians with easy access to fabricate patient specific bolus accommodating patient body surface irregularities and tissue inhomogeneity. This study presents the design and the clinical workflow of 3D printed bolus for patient electron therapy in our clinic. Methods: Patient simulation CT images free of bolus were exported from treatment planning system (TPS) to an in-house developed software package. Bolus with known material properties was designed in the software package and then exported back to the TPS as a structure. Dose calculation was carried out to examine the coverage of the target. After satisfying dose distribution was achieved, the bolus structure was transferred in Standard Tessellation Language (STL) file format for the 3D printer to generate the machine codes for printing. Upon receiving printed bolus, a quick quality assurance was performed with patient resimulated with bolus in place to verify the bolus dosimetric property before treatment started. Results: A patient specific bolus for electron radiotherapy was designed and fabricated in Form 1 3D printer with methacrylate photopolymer resin. Satisfying dose distribution was achieved in patient with bolus setup. Treatment was successfully finished for one patient with the 3D printed bolus. Conclusion: The electron bolus fabrication with 3D printing technology was successfully implemented in clinic practice.

Episodic chasing in pathological gamblers using the Iowa gambling task

DEFF Research Database (Denmark)

Linnet, J.; Rojskjaer, S.; Nygaard, Jørgen

2006-01-01

NPGs on the Iowa Gambling Task (IGT) and the Zuckerman Sensation Seeking Scale (SSS). The PGs showed significantly more chasing and had significantly poorer decision-making strategies than NPGs, particularly among males (F = 4.52, p

Thoracic pathologies on scout views and bolus tracking slices for computed tomographic cerebral angiography

Energy Technology Data Exchange (ETDEWEB)

Groth, M.; Fiehler, J.; Buhk, J.H. [University Medical Center Hamburg-Eppendorf (Germany). Dept. of Diagnostic and Interventional Neuroradiology; Henes, F.O. [University Medical Center Hamburg-Eppendorf (Germany). Dept. of Diagnostic and Interventional Radiology

2015-08-15

To evaluate the incidence of additional thoracic pathologic findings (TPF) detected on scout views and corresponding bolus tracking slices (SVBT) for computed tomographic cerebral angiography (CTCA) and to test the reliability and accuracy of these findings. The study collective included 505 consecutive patients who underwent multidetector CTCA. Appendant SVBT of all patients were reviewed for any pathologic findings and patient medical reports were analyzed, if any medical treatment was initiated for the detected pathologic findings. In 18 patients thoracic CT scans were performed in the same session. These were additionally reviewed by two blinded observers to test for intra- and interobserver reliability as well as for accuracy of detecting thoracic pathologies on SVBT. TPF were detected in 165 (33 %) SVBT. The five most common pathologic findings were: pleural effusion, 12 %; pneumonia, 8 %; atelectasis/dystelecatsis, 6 %; pericardial effusion, 2 % and elevated diaphragm, 1 %. For 48 % of these findings medical treatment was initiated. SVBT showed a sensitivity of 53 %, a specificity of 99 %, a positive predictive value of 89 %, a negative predictive value of 94 % and accuracy of 94 % for the detection of TPF. The intraobserver reliability was very good and the interobserver reliability showed moderate agreement. SVBT for CTCA should be reviewed with care by radiologists, since additional TPF can affect patient management. Nevertheless, despite a high specificity of SVBT for detecting TPF, an only moderate sensitivity has to be taken into account.

Serum levels of bupivacaine after pre-peritoneal bolus vs. epidural bolus injection for analgesia in abdominal surgery: A safety study within a randomized controlled trial.

Science.gov (United States)

Mungroop, Timothy H; van Samkar, Ganapathy; Geerts, Bart F; van Dieren, Susan; Besselink, Marc G; Veelo, Denise P; Lirk, Philipp

2017-01-01

Continuous wound infiltration (CWI) has become increasingly popular in recent years as an alternative to epidural analgesia. As catheters are not placed until the end of surgery, more intraoperative opioid analgesics might be needed. We, therefore, added a single pre-peritoneal bolus of bupivacaine at the start of laparotomy, similar to the bolus given with epidural analgesia. This was a comparative study within a randomized controlled trial (NTR4948). Patients undergoing hepato-pancreato-biliary surgery received either a pre-peritoneal bolus of 30ml bupivacaine 0.25%, or an epidural bolus of 10ml bupivacaine 0.25% at the start of laparotomy. In a subgroup of patients, we sampled blood and determined bupivacaine serum levels 20, 40, 60 and 80 minutes after bolus injection. We assumed toxicity of bupivacaine to be >1000 ng/ml. A total of 20 patients participated in this sub-study. All plasma levels measured as well as the upper limit of the predicted 99% confidence intervals per time point were well below the toxicity limit. In a mixed linear-effect model both groups did not differ statistically significant (p = 0.131). The intra-operative use of opioids was higher with CWI as compared to epidural (86 (SD 73) μg sufentanil vs. 50 (SD 32). In this exploratory study, the pre-peritoneal bolus using bupivacaine resulted in serum bupivacaine concentrations well below the commonly accepted toxic threshold. With CWI more additional analgesics are needed intraoperatively as compared to epidural analgesia, although this is compensated by a reduction in use of vasopressors with CWI. Netherlands Trial Register NTR4948.

Assessment of myocardial perfusion with MRI using a modified dual bolus method

International Nuclear Information System (INIS)

Husso, M; Sipola, P; Manninen, H; Vainio, P; Kuittinen, T; Hartikainen, J; Saarakkala, S; Töyräs, J; Kuikka, J

2014-01-01

Quantification of regional myocardial blood flow (rMBF) with first-pass magnetic resonance imaging (FP-MRI) requires two contrast agent injections (dual bolus technique), inducing error in the determined rMBF if the injections differ. We hypothesize that using input and residue curves of the same injection would be more reliable. We aim to introduce and evaluate a novel method to correct the high concentration arterial input function (AIF) for determination of rMBF. Sixteen patients with non-Hodgkin's lymphoma were examined before and after chemotherapy. The input function was solved by correcting initial high concentration AIF using the ratio of low and high contrast AIF areas, normalized by corresponding heart rates (modified dual bolus method). For comparison, the scaled low contrast AIF was used as an input function (dual bolus method). Unidirectional transfer coefficient K trans  was calculated using both methods. K trans -values determined with the dual bolus (0.81 ± 0.32 ml g −1  min −1 ) and modified dual bolus (0.77 ± 0.42 ml g −1  min −1 ) methods were in agreement (p = 0.21). Mean K trans -values increased from 0.76 ± 0.43 to 0.89 ± 0.55 ml g −1  min −1  after chemotherapy (p = 0.17). The modified dual bolus technique agrees with the dual bolus technique (R2 = 0.899) when the low and high contrast injections are similar. However, when this is not the case, the modified dual bolus technique may be more reliable. (paper)

Assessment of bolus transit with intraluminal impedance measurement in patients with esophageal motility disorders.

Science.gov (United States)

Bogte, A; Bredenoord, A J; Oors, J; Siersema, P D; Smout, A J P M

2015-10-01

The clinical management of patients with non-obstructive dysphagia is notoriously difficult. Esophageal impedance measurement can be used to measure esophageal bolus transit without the use of radiation exposure to patients. However, validation of measurement of bolus transit with impedance monitoring has only been performed in healthy subjects with normal motility and not in patients with dysphagia and esophageal motility disorders. The aim was, therefore, to investigate the relationship between transit of swallowed liquid boluses in healthy controls and in patients with dysphagia. Twenty healthy volunteers and 20 patients with dysphagia underwent concurrent impedance measurement and videofluoroscopy. Each subject swallowed five liquid barium boluses. The ability of detecting complete or incomplete bolus transit by means of impedance measurement was assessed, using radiographic bolus transit as the gold standard. Impedance monitoring recognized stasis and transit in 80.5% of the events correctly, with 83.9% of bolus transit being recognized and 77.2% of stasis being recognized correctly. In controls 79.8% of all swallows were scored correctly, whereas in patients 81.3% of all swallows were scored correctly. Depending on the contractility pattern, between 77.0% and 94.3% of the swallows were scored correctly. Impedance measurement can be used to assess bolus clearance patterns in healthy subjects, but can also be used to reliably assess bolus transit in patients with dysphagia and motility disorders. © 2015 John Wiley & Sons Ltd.

Chasing losses in online poker and casino games: characteristics and game play of Internet gamblers at risk of disordered gambling.

Science.gov (United States)

Gainsbury, Sally M; Suhonen, Niko; Saastamoinen, Jani

2014-07-30

Disordered Internet gambling is a psychological disorder that represents an important public health issue due to the increase in highly available and conveniently accessible Internet gambling sites. Chasing losses is one of the few observable markers of at-risk and problem gambling that may be used to detect early signs of disordered Internet gambling. This study examined loss chasing behaviour in a sample of Internet casino and poker players and the socio-demographic variables, irrational beliefs, and gambling behaviours associated with chasing losses. An online survey was completed by 10,838 Internet gamblers (58% male) from 96 countries. The results showed that Internet casino players had a greater tendency to report chasing losses than poker players and gamblers who reported chasing losses were more likely to hold irrational beliefs about gambling and spend more time and money gambling than those who reported that they were unaffected by previous losses. Gamblers who played for excitement and to win money were more likely to report chasing losses. This study is one of the largest ever studies of Internet gamblers and the results are highly significant as they provide insight into the characteristics and behaviours of gamblers using this mode of access. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Cooperative and Human Aspects of Software Engineering (CHASE 2008)

DEFF Research Database (Denmark)

2008-01-01

ethnographic research to experiments. Moreover, the background of attendees reflects the diversity of researchers in this domain, ranging from sociology to psychology, from informatics to software engineering. CHASE 1008 met its goals in presenting high-quality research and building community through a mixture...... of presentations, discussions, posters, and social activities....

Barium and meat. A comparison between pharyngeal swallow of fluid and solid boluses

Energy Technology Data Exchange (ETDEWEB)

Ekberg, O.; Liedberg, B.; Oewall, B.

The influence of bolus consistency on pharyngeal swallow was radiologically studied in 24 individuals by comparing liquid barium and solid meat after chewing. Pharyngeal function was apparently performed synchronously and symmetrically on both boluses. No definite conclusion about the influence on epiglottic mobility, closure of the laryngeal vestibule and relaxation of the circopharyngeal muscle could be drawn from this study. There was no difference in the elevation of the pharynx and larynx. The transit time for a solid bolus was shorter compared with that of a fluid bous. The transit time for the apex of the bolus was shorter than for the tail. A more marked elevation of the pharynx and larynx was followed by a shorter transit time. The width of the pharyngo-esophageal segment was larger in the transverse than in the sagittal diameter during the passage of the bolus and larger on solid compared with fluid swallow. Our results reflect the ability of pharyngeal swallow to be executed with precision and with few alterations due to variable bolus consistency.

Volatilisation of diacetylmorphine: in vitro simulation of 'chasing the dragon'

NARCIS (Netherlands)

Klous, M. G.; Lee, W. C.; van den Brink, W.; van Ree, J. M.; Beijnen, J. H.

2006-01-01

In preparation for a trial on co-prescription of heroin to chronic treatment-resistant addicts, a pharmaceutical dosage form for smokable heroin was developed. During development of this product (a mixture of diacetylmorphine and caffeine), in vitro experiments were performed simulating 'chasing the

Sensation of stasis is poorly correlated with impaired esophageal bolus transport

NARCIS (Netherlands)

Bogte, A.; Bredenoord, A. J.; Oors, J.; Siersema, P. D.; Smout, A. J. P. M.

2014-01-01

It is common belief that symptoms of patients with non-obstructive dysphagia are the result of impaired bolus clearance in the esophagus, usually caused by esophageal motility disorders. We therefore investigated the relationship between transit of swallowed boluses and the symptom dysphagia. Twenty

A Patient-Specific Polylactic Acid Bolus Made by a 3D Printer for Breast Cancer Radiation Therapy.

Science.gov (United States)

Park, So-Yeon; Choi, Chang Heon; Park, Jong Min; Chun, MinSoo; Han, Ji Hye; Kim, Jung-In

2016-01-01

The aim of this study was to assess the feasibility and advantages of a patient-specific breast bolus made using a 3D printer technique. We used the anthropomorphic female phantom with breast attachments, which volumes are 200, 300, 400, 500 and 650 cc. We simulated the treatment for a right breast patient using parallel opposed tangential fields. Treatment plans were used to investigate the effect of unwanted air gaps under bolus on the dose distribution of the whole breast. The commercial Super-Flex bolus and 3D-printed polylactic acid (PLA) bolus were applied to investigate the skin dose of the breast with the MOSFET measurement. Two boluses of 3 and 5 mm thicknesses were selected. There was a good agreement between the dose distribution for a virtual bolus generated by the TPS and PLA bolus. The difference in dose distribution between the virtual bolus and Super-Flex bolus was significant within the bolus and breast due to unwanted air gaps. The average differences between calculated and measured doses in a 200 and 300 cc with PLA bolus were not significant, which were -0.7% and -0.6% for 3mm, and -1.1% and -1.1% for 5 mm, respectively. With the Super-Flex bolus, however, significant dose differences were observed (-5.1% and -3.2% for 3mm, and -6.3% and -4.2% for 5 mm). The 3D-printed solid bolus can reduce the uncertainty of the daily setup and help to overcome the dose discrepancy by unwanted air gaps in the breast cancer radiation therapy.

Chasing molecules: poisonous products, human health, and the promise of green chemistry

National Research Council Canada - National Science Library

Grossman, Elizabeth

2009-01-01

In Chasing Molecules, investigative journalist Elizabeth Grossman opens the door on a new world of chemistry-green chemistry - and the scientists who are unearthing the field's potential to transform...

Dextrose boluses versus burette dextrose infusions in prevention of hypoglycemia among preterms admitted at Mulago Hospital: an open label randomized clinical trial.

Science.gov (United States)

Kutamba, E; Lubega, S; Mugalu, J; Ouma, J; Mupere, E

2014-09-01

Hypoglycemia is a major cause of morbidity and mortality among preterm infants and its management remains a challenge in resource limited settings. Use of dextrose infusion by the recommended infusion pumps is not feasible in our environment due to their high costs and yet the current use of mini dextrose boluses with syringes as adapted at Mulago national referral and tertiary teaching hospital has unknown efficacy in prevention of hypoglycemia. We determined the efficacy of dextrose infusions by burettes versus two hourly dextrose boluses in prevention of hypoglycemia among preterms admitted in the first 72 hours at Special Care Unit, Mulago Hospital. One hundred and forty preterms aged 0 to 24 hours of life were randomized to receive 10% IV dextrose either as mini boluses or by infusion using burettes in an open label clinical trial. Blood glucose was measured at 0, two hourly for next 6 hours, 6 hourly for next 12 hours and thereafter 12 hourly until end of 72 hours following admission. Primary end point was incidence of hypoglycemia (random blood sugar (RBS) dextrose infusion was computed using 1-RR. From February 2012 to April 2012, 68 preterms in the bolus arm and 72 in the infusion arm were studied. Hypoglycemia was detected in 34% (48/140). The incidence of hypoglycemia in the bolus arm was 59% (40/68) compared to 11% (8/72) in the infusion arm (RR; 0.19, 95% CI; 0.09-0.37). Efficacy (1-RR) of infusion by burettes versus boluses in prevention of hypoglycemia among preterms was 0.81 (95% CI; 0.63-0.90). Continuous 10% dextrose infusion by burettes reduced the incidence of hypoglycemia by 81% in the first 72 hours of admission compared to two hourly 10% mini dextrose boluses among preterms admitted at Special Care Unit, Mulago Hospital. (ClinicalTrials.gov Identifier: NCT01688674).

The usefulness of esophagogram with marchmallow bolus in patients with esophageal related symptoms

Energy Technology Data Exchange (ETDEWEB)

Yoon, Sang Wook; Kim, Ki Whang; Park, Hyo Jin; Kim, Eun Kyung; Yu, Jeong Sik; Seo, Jung Kun; Kwon, Ryang; Shin, Hyung Cheol [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

1996-03-01

To evaluate the usefulness of the esophagogram using marshmallow bolus in the evaluation of the causes of variable esophageal-related symptoms. Esophagograms using marshmallow bolus were performed on 44 patients with esophageal-related symptoms and on ten normal volunteers. Videofluoroscopic studies were also made. Patients were classified into three groups according to their esophageal-related symptoms ; those with dysphagia, those with globus symptom, and those with chest pain. Abnormal findings on an esophagogram with marshmallow were graded in to three categories ; mild, moderate, and severe. Provocation of the same symptom was also evaluated. Esophageal monometric studies were performed on 16 patients and those results were compared with the results obtained from the esophagogram using marshmallow bolus. The provocation rate of the some symptom was 33% in the first group, 47% in the second, and 24% in the third. The provocation rate was highest in the second group. The provocation rate was also higher in patients with a severe degree of abnormality on an esophagogram using marshmallow bolus. Where there were abnormal findings, an esophagogram using marshmallow bolus showed a higher abnormality rate than did a conventional esophagogram. In cases showing abnormal finding son the esophageal monometric study, an esophagogram using marshmallow bolus showed a higher provocation rate and more severe abnormality than in cases showing normal findings on manometric study. An esophagogram using marshmallow bolus will a useful radiologic screening modality for the evaluation of patients with esophageal-related symptoms.

The usefulness of esophagogram with marchmallow bolus in patients with esophageal related symptoms

International Nuclear Information System (INIS)

Yoon, Sang Wook; Kim, Ki Whang; Park, Hyo Jin; Kim, Eun Kyung; Yu, Jeong Sik; Seo, Jung Kun; Kwon, Ryang; Shin, Hyung Cheol

1996-01-01

To evaluate the usefulness of the esophagogram using marshmallow bolus in the evaluation of the causes of variable esophageal-related symptoms. Esophagograms using marshmallow bolus were performed on 44 patients with esophageal-related symptoms and on ten normal volunteers. Videofluoroscopic studies were also made. Patients were classified into three groups according to their esophageal-related symptoms ; those with dysphagia, those with globus symptom, and those with chest pain. Abnormal findings on an esophagogram with marshmallow were graded in to three categories ; mild, moderate, and severe. Provocation of the same symptom was also evaluated. Esophageal monometric studies were performed on 16 patients and those results were compared with the results obtained from the esophagogram using marshmallow bolus. The provocation rate of the some symptom was 33% in the first group, 47% in the second, and 24% in the third. The provocation rate was highest in the second group. The provocation rate was also higher in patients with a severe degree of abnormality on an esophagogram using marshmallow bolus. Where there were abnormal findings, an esophagogram using marshmallow bolus showed a higher abnormality rate than did a conventional esophagogram. In cases showing abnormal finding son the esophageal monometric study, an esophagogram using marshmallow bolus showed a higher provocation rate and more severe abnormality than in cases showing normal findings on manometric study. An esophagogram using marshmallow bolus will a useful radiologic screening modality for the evaluation of patients with esophageal-related symptoms

Enhancing automatic closed-loop glucose control in type 1 diabetes with an adaptive meal bolus calculator - in silico evaluation under intra-day variability.

Science.gov (United States)

Herrero, Pau; Bondia, Jorge; Adewuyi, Oloruntoba; Pesl, Peter; El-Sharkawy, Mohamed; Reddy, Monika; Toumazou, Chris; Oliver, Nick; Georgiou, Pantelis

2017-07-01

Current prototypes of closed-loop systems for glucose control in type 1 diabetes mellitus, also referred to as artificial pancreas systems, require a pre-meal insulin bolus to compensate for delays in subcutaneous insulin absorption in order to avoid initial post-prandial hyperglycemia. Computing such a meal bolus is a challenging task due to the high intra-subject variability of insulin requirements. Most closed-loop systems compute this pre-meal insulin dose by a standard bolus calculation, as is commonly found in insulin pumps. However, the performance of these calculators is limited due to a lack of adaptiveness in front of dynamic changes in insulin requirements. Despite some initial attempts to include adaptation within these calculators, challenges remain. In this paper we present a new technique to automatically adapt the meal-priming bolus within an artificial pancreas. The technique consists of using a novel adaptive bolus calculator based on Case-Based Reasoning and Run-To-Run control, within a closed-loop controller. Coordination between the adaptive bolus calculator and the controller was required to achieve the desired performance. For testing purposes, the clinically validated Imperial College Artificial Pancreas controller was employed. The proposed system was evaluated against itself but without bolus adaptation. The UVa-Padova T1DM v3.2 system was used to carry out a three-month in silico study on 11 adult and 11 adolescent virtual subjects taking into account inter-and intra-subject variability of insulin requirements and uncertainty on carbohydrate intake. Overall, the closed-loop controller enhanced by an adaptive bolus calculator improves glycemic control when compared to its non-adaptive counterpart. In particular, the following statistically significant improvements were found (non-adaptive vs. adaptive). Adults: mean glucose 142.2 ± 9.4vs. 131.8 ± 4.2mg/dl; percentage time in target [70, 180]mg/dl, 82.0 ± 7.0vs. 89.5 ± 4

Assessment of injection bolus in first-pass radionuclide angiography. Evaluation of injection site and needle size

International Nuclear Information System (INIS)

Tonami, Syuichi; Inagaki, Syoichi; Yasui, Masakazu; Sugishita, Kouki; Yoshita, Hisashi; Nakamura, Mamoru; Kuranishi, Makoto

1996-01-01

First-pass radionuclide angiography (FPRNA) using a multi-crystal gamma camera can correctly provide many quantitative and qualitative indices of left ventricular function as well as anatomic information. A compact injection bolus of radiotracer is, however, essential to the first-pass study since the temporal separation of cardiac chambers is required for the first-pass acquisition. To examine which factors affect the quality of an injection bolus, 327 patients who had FPRNA in the anterior projection were randomized for injection site of radiotracer (right or left external jugular veins, and right antecubital vein) and needle size (19- or 21-gauge). The injected bolus was assessed from the full width at half maximum (FWHM) of the bolus time-activity curve in the superior vena cava. As to injection site using a 19-gauge needle, an attemption through right external jugular vein (EJV) revealed the shortest FWHM of an injection bolus, followed by left EJV and right antecubital vein (AV). In right EJV 91% of injected bolus FWHM was less than 1.5 sec, which was significantly higher (p<0.001) than those of the other sites (left EJV: 70%. right AV: 65%). Approximately 7% of injection from left EJV and right AV, showed a split bolus of radiotracer. However, no split bolus was observed from right EJV. There was no significant difference in FWHM of an injection bolus between 19- and 21-gauge needle from EJV. Our present study demonstrated that the quality of an injection bolus from left EJV and AV was affected by RVEF in a case of low right ventricular function. In conclusion, right EJV is the first choice of injection site to obtain a compact bolus of radiotracer for the first-pass cardiac study. A 21-gauge needle can also be inserted from the external jugular vein to perform a good bolus injection. (author)

Assessment of injection bolus in first-pass radionuclide angiography. Evaluation of injection site and needle size

Energy Technology Data Exchange (ETDEWEB)

Tonami, Syuichi; Inagaki, Syoichi; Yasui, Masakazu; Sugishita, Kouki; Yoshita, Hisashi; Nakamura, Mamoru; Kuranishi, Makoto [Toyama Medical and Pharmaceutical Univ. (Japan). Hospital

1996-09-01

First-pass radionuclide angiography (FPRNA) using a multi-crystal gamma camera can correctly provide many quantitative and qualitative indices of left ventricular function as well as anatomic information. A compact injection bolus of radiotracer is, however, essential to the first-pass study since the temporal separation of cardiac chambers is required for the first-pass acquisition. To examine which factors affect the quality of an injection bolus, 327 patients who had FPRNA in the anterior projection were randomized for injection site of radiotracer (right or left external jugular veins, and right antecubital vein) and needle size (19- or 21-gauge). The injected bolus was assessed from the full width at half maximum (FWHM) of the bolus time-activity curve in the superior vena cava. As to injection site using a 19-gauge needle, an attemption through right external jugular vein (EJV) revealed the shortest FWHM of an injection bolus, followed by left EJV and right antecubital vein (AV). In right EJV 91% of injected bolus FWHM was less than 1.5 sec, which was significantly higher (p<0.001) than those of the other sites (left EJV: 70%. right AV: 65%). Approximately 7% of injection from left EJV and right AV, showed a split bolus of radiotracer. However, no split bolus was observed from right EJV. There was no significant difference in FWHM of an injection bolus between 19- and 21-gauge needle from EJV. Our present study demonstrated that the quality of an injection bolus from left EJV and AV was affected by RVEF in a case of low right ventricular function. In conclusion, right EJV is the first choice of injection site to obtain a compact bolus of radiotracer for the first-pass cardiac study. A 21-gauge needle can also be inserted from the external jugular vein to perform a good bolus injection. (author)

The use of Coca-Cola in the management of bolus obstruction in benign oesophageal stricture.

Science.gov (United States)

Karanjia, N. D.; Rees, M.

1993-01-01

Oesophageal stricture is a complication of oesophageal reflux and may itself be complicated by bolus obstruction. We reviewed the records of patients presenting with dysphagia and who were found to have benign oesophageal strictures. We studied the outcome of bolus obstruction in 13 episodes affecting eight patients. In six episodes Coca-Cola was administered on the day before endoscopy, and in all these patients the bolus had cleared. In seven episodes nothing was administered before endoscopy, and in all seven a bolus was evident at endoscopy. In five of these seven the bolus was removed piecemeal and in each of these instances the endoscope had to be passed between two and five times. In the remaining two instances the procedure was abandoned and the patients returned to the ward for the administration of Coca-Cola. At subsequent endoscopy these patients were found to be clear of any bolus. These results suggest that the administration of Coca-Cola (or other aerated drinks) may clear a bolus in the acutely obstructed oesophagus. PMID:8476194

Oral declines and mastication deficiencies cause alteration of food bolus properties.

Science.gov (United States)

Peyron, M-A; Santé-Lhoutellier, V; François, O; Hennequin, M

2018-02-21

In the elderly, masticatory function often presents failure in certain oral tasks due to impairment such as decline in muscular force, jaw or tongue motility, neuro-muscular coordination, tooth damage, malocclusion and saliva production. Great disparity is observed in the various and potentially cumulative oral declines that occur with ageing. Such difficulties may have an impact on food consumption and nutritional status. To obtain better understanding of the consequences of several oral deficiencies, a series of swallowable boluses were prepared in vitro with the AM 2 masticator apparatus with normal and deficient programming. Physiological normal mastication (NM) was simulated using in vivo data from healthy subjects. Chewing deficiencies were reproduced by alteration of NM programming to perform different levels and combinations of force loss, lack of saliva and decrease in the motility of oral elements. Poultry meatballs were used as test-food. Particle size distribution in the food bolus was measured by sieving and rheological features (hardness, cohesiveness and elasticity) were assessed with a TPA test. Compared to the NM outcome, significant and gradual deterioration of the food bolus was observed and associated with alteration in force, saliva and motility. Combinations of several failures led to greater or cumulative deficiencies in swallowable bolus properties. For the elderly presenting a high prevalence of various oral injuries, tailoring textured food cannot be ignored as a solution for remedying deficiencies and favoring the formation of a safe-swallowable bolus, which is an essential vector of nutrients. Knowing the impacts of oral injuries on the food bolus is obviously a requisite for developing diet strategies, including nutritional items for specific populations.

A Patient-Specific Polylactic Acid Bolus Made by a 3D Printer for Breast Cancer Radiation Therapy.

Directory of Open Access Journals (Sweden)

So-Yeon Park

Full Text Available The aim of this study was to assess the feasibility and advantages of a patient-specific breast bolus made using a 3D printer technique.We used the anthropomorphic female phantom with breast attachments, which volumes are 200, 300, 400, 500 and 650 cc. We simulated the treatment for a right breast patient using parallel opposed tangential fields. Treatment plans were used to investigate the effect of unwanted air gaps under bolus on the dose distribution of the whole breast. The commercial Super-Flex bolus and 3D-printed polylactic acid (PLA bolus were applied to investigate the skin dose of the breast with the MOSFET measurement. Two boluses of 3 and 5 mm thicknesses were selected.There was a good agreement between the dose distribution for a virtual bolus generated by the TPS and PLA bolus. The difference in dose distribution between the virtual bolus and Super-Flex bolus was significant within the bolus and breast due to unwanted air gaps. The average differences between calculated and measured doses in a 200 and 300 cc with PLA bolus were not significant, which were -0.7% and -0.6% for 3mm, and -1.1% and -1.1% for 5 mm, respectively. With the Super-Flex bolus, however, significant dose differences were observed (-5.1% and -3.2% for 3mm, and -6.3% and -4.2% for 5 mm.The 3D-printed solid bolus can reduce the uncertainty of the daily setup and help to overcome the dose discrepancy by unwanted air gaps in the breast cancer radiation therapy.

Rapid contrast infusion of bolus injection for i.v. urography

International Nuclear Information System (INIS)

Kaltenborn, H.; Klose, P.; Klose, K.; Schmiedel, E.

1993-01-01

The rate of contrast injection during i.v. urography may vary considerably (bolus injection or drip infusion). The effect of 5 rates of injection (6, 12, 18, 36 and 72 ml/min) on the contrast density in the renal collecting system was examined over a period of 30 minutes. Measurements showed an inter-individual difference of more than 200% in each group. The intra-individual variations for different rates of injection were very slight; individual concentration in the kidney for a given dose depends only slightly on the rate of injection. There is no statistically significant improvement in contrast values as a result of a bolus injection. The reduced incidence of side effects justifies the use of bolus injections but pressure injections are unnecessary from a diagnostic point view. (orig.) [de

Evaluation of reconstruction parameters of electrical impedance tomography on aorta detection during saline bolus injection

Directory of Open Access Journals (Sweden)

Thürk Florian

2016-09-01

Full Text Available An accurate detection of anatomical structures in electrical impedance tomography (EIT is still at an early stage. Aorta detection in EIT is of special interest, since it would favor non-invasive assessment of hemodynamic processes in the body. Here, diverse EIT reconstruction parameters of the GREIT algorithm were systematically evaluated to detect the aorta after saline bolus injection in apnea. True aorta position and size were taken from computed tomography (CT. A comparison with CT showed that the smallest error for aorta displacement was attained for noise figure nf = 0.7, weighting radius rw = 0.15, and target size ts = 0.01. The spatial extension of the aorta was most precise for nf = 0.7, rw = 0.25, and ts = 0.07. Detection accuracy (F1-score was highest with nf = 0.6, rw = 0.15, and ts = 0.04. This work provides algorithm-related evidence for potentially accurate aorta detection in EIT after injection of a saline bolus.

Dynamic computed tomography after bolus injection and infusion of perfluorooctylbromide (PFOB). Computertomographische Untersuchungen zur Dichtekinetik nach Bolusinjektion und Infusion von Perfluorooctylbromid (PFOB). Tierexperimentelle Untersuchungen

Energy Technology Data Exchange (ETDEWEB)

Adam, G.; Guenther, R.W.; Goertz, H.; Schiffer, C. (Technische Hochschule Aachen (Germany). Klinik fuer Radiologische Diagnostik); Prescher, A. (Technische Hochschule Aachen (Germany). Inst. fuer Anatomie); Bruchmueller, K. (Technische Hochschule Aachen (Germany). Inst. fuer Versuchstierkunde); Limmer, J. (Boehringer Ingelheim GmbH (Germany))

1992-05-01

We investigated the enhancement of the liver, the spleen, and of induced abscesses and the abdominal vessels after administration of 3 g/kg bodyweight Perfluoroocytlbromide (PFOB) on an animal model. Twenty-one rabbits each received the contrast medium as bolus injection and as slow infusion over half an hour. CT was performed between 2 and 48 hours after contrast medium application. Peak enhancement of the liver, the spleen and the liver abscess membrane was found between 24 and 48 hours after PFOB administration, independently of the application mode. Peak enhancement of the abdominal aorta and the IVC was observed within two hours after bolus injection. In this rabbit model PFOB permits best delineation of the vessels after bolus injection within the first two hours, while CT imaging of the liver, the spleen and the liver abscess membrane is best between 24 and 48 hours after contrast medium application, independent of the injection velocity. (orig.).

A Bolus Calculator Based on Continuous-Discrete Unscented Kalman Filtering for Type 1 Diabetics

DEFF Research Database (Denmark)

Boiroux, Dimitri; Aradóttir, Tinna Björk; Hagdrup, Morten

2015-01-01

both reduces the risk of hypoglycemia in case of an overestimated meal and the time spent in hyperglycemia if the meal size is underestimated. Faster insulin and the use of glucagon will have the potential to encourage postprandial meal bolus administration and hence will not require to accurately......In patients with type 1 diabetes, the effects of meals intake on blood glucose level are usually mitigated by administering a large amount of insulin (bolus) at mealtime or even slightly before. This strategy assumes, among other things, a prior knowledge of the meal size and the postprandial...... glucose dynamics. On the other hand, administering the meal bolus during or after mealtime could benefit from the information provided by the postprandial meal dynamics at the expense of a delayed meal bolus. The present paper investigates different bolus administration strategies (at mealtime, 15 minutes...

[Observing the density increase curve after intravenous contrast medium administration using a bolus triggering system: a method for detection cardiovascular disorders?].

Science.gov (United States)

Stückle, C A; Kickuth, R; Kirchner, E M; Liermann, D; Kirchner, J

2002-06-01

Recently bolus tracking systems were developed to improve the timing of intravenous contrast media application in helical computed tomography. We investigated the benefit of this new method as a parameter of the cardiac function. Retrospective analysis of 64 patients which incidentally underwent bolus triggered contrast enhanced helical CT and invasive investigation of the heart within one week. All examinations were performed on the CT scanner Somatom Plus 4 Volume Zoom (Siemens Corp., Forchheim, Germany) using the C.A.R.E. Bolus software. This performs repetitive low-dose test scans (e.g. for the abdomen: 140 kV, 20 mA, Tl 0.5 s) and measures the Hounsfield attenuation (increase over the baseline) in a preselected region of interest. The displayed increase of vascular density over the time after peripheral contrast media injection (75 ml lopromid (300 mg/ml), 2 ml/s) was categorised to three types: (a) rapid increase, (b) deceleration before a 100 HE threshold was reached and (c) one or more peaks. The findings of the invasive investigation of the heart were correlated to the findings of the bolus-tracking measurements. The examinations were categorized as follows: 19 type A, 34 type B, 11 type C. We found a high significant correlation between the type of the Hounsfield attenuation and systolic pressure in the left ventricle. There was no correlation between the type of the Hounsfield attenuation and the diastolic pressure in the left ventricle, the pressures related to the right ventricle or the ejection fraction. The bolus-tacking system showed a sensitivity of 53, a specificity of 82, an accuracy of 70%, a positive predictive value of 70% and a negative predictive value of 70% in detection of left heart failure. The bolus tracking system C.A.R.E.-bolus often shows atypical Hounsfield attenuation in cases of cardiac failure but is not suitable as a screening method of the cardiopulmonary function.

21 CFR 520.1242b - Levamisole hydrochloride tablet or oblet (bolus).

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Levamisole hydrochloride tablet or oblet (bolus... § 520.1242b Levamisole hydrochloride tablet or oblet (bolus). (a) Chemical name. (-)-2,3,5,6-Tetrahydro... using in severely debilitated animals. (2) It is used in a tablet for sheep as follows: (i) Amount. 0...

Evaluation of a Water-based Bolus Device for Radiotherapy to the Extremities in Kaposi's Sarcoma Patients

International Nuclear Information System (INIS)

Ahn, Seung Kwon; Kim, Yong Bae; Lee, Ik Jae

2008-01-01

We designed a water-based bolus device for radiation therapy in Kaposi's sarcoma. This study evaluated the usefulness of this new device and compared it with the currently used rice-based bolus. Materials and Methods: We fashioned a polystyrene box and cut a hole in order to insert patient's extremities while the patient was in the supine position. We used a vacuum-vinyl based polymer to reduce water leakage. Next, we eliminated air using a vacuum pump and a vacuum valve to reduce the air gap between the water and extremities in the vacuum-vinyl box. We performed CT scans to evaluate the density difference of the fabricated water-based bolus device when the device in which the rice-based bolus was placed directly, the rice-based bolus with polymer-vinyl packed rice, and the water were all put in. We analyzed the density change with the air gap volume using a planning system. In addition, we measured the homogeneity and dose in the low-extremities phantom, attached to six TLD, and wrapped film exposed in parallel-opposite fields with the LINAC under the same conditions as the set-up of the CT-simulator. Results: The density value of the rice-based bolus with the rice put in directly was 14% lower than that of the water-based bolus. Moreover, the value of the other experiments in the rice-based bolus with the polymer-vinyl packed rice showed an 18% reduction in density. The analysis of the EDR2 film revealed that the water-based bolus shows a more homogeneous dose plan, which was superior by 4.0-4.4% to the rice-base bolus. The mean TLD readings of the rice-based bolus, with the rice put directly into the polystyrene box had a 3.4% higher density value. Moreover, the density value in the case of the rice-based bolus with polymer-vinyl packed rice had a 4.3% higher reading compared to the water-based bolus. Conclusion: Our custom-made water-based bolus device increases the accuracy of the set-up by confirming the treatment field. It also improves the accuracy of the

Chasing behaviour and optomotor following in free-flying male blowflies: flight performance and interactions of the underlying control systems

Directory of Open Access Journals (Sweden)

Christine Trischler

2010-05-01

Full Text Available The chasing behaviour of male blowflies after small targets belongs to the most rapid and virtuosic visually guided behaviours found in nature. Since in a structured environment any turn towards a target inevitably leads to a displacement of the entire retinal image in the opposite direction, it might evoke optomotor following responses counteracting the turn. To analyse potential interactions between the control systems underlying chasing behaviour and optomotor following, respectively, we performed behavioural experiments on male blowflies and examined the characteristics of the two flight control systems in isolation and in combination. Three findings are particularly striking. (i The characteristic saccadic flight and gaze style – a distinctive feature of blowfly cruising flights – is largely abandoned when the entire visual surroundings move around the fly; in this case flies tend to follow the moving pattern in a relatively continuous and smooth way. (ii When male flies engage in following a small target, they also employ a smooth pursuit strategy. (iii Although blowflies are reluctant to fly at high background velocities, the performance and dynamical characteristics of the chasing system are not much affected when the background moves in either the same or in the opposite direction as the target. Hence, the optomotor following response is largely suppressed by the chasing system and does not much impair chasing performance.

Delivery confirmation of bolus electron conformal therapy combined with intensity modulated x-ray therapy

International Nuclear Information System (INIS)

Kavanaugh, James A.; Hogstrom, Kenneth R.; Fontenot, Jonas P.; Henkelmann, Gregory; Chu, Connel; Carver, Robert A.

2013-01-01

Purpose: The purpose of this study was to demonstrate that a bolus electron conformal therapy (ECT) dose plan and a mixed beam plan, composed of an intensity modulated x-ray therapy (IMXT) dose plan optimized on top of the bolus ECT plan, can be accurately delivered. Methods: Calculated dose distributions were compared with measured dose distributions for parotid and chest wall (CW) bolus ECT and mixed beam plans, each simulated in a cylindrical polystyrene phantom that allowed film dose measurements. Bolus ECT plans were created for both parotid and CW PTVs (planning target volumes) using 20 and 16 MeV beams, respectively, whose 90% dose surface conformed to the PTV. Mixed beam plans consisted of an IMXT dose plan optimized on top of the bolus ECT dose plan. The bolus ECT, IMXT, and mixed beam dose distributions were measured using radiographic films in five transverse and one sagittal planes for a total of 36 measurement conditions. Corrections for film dose response, effects of edge-on photon irradiation, and effects of irregular phantom optical properties on the Cerenkov component of the film signal resulted in high precision measurements. Data set consistency was verified by agreement of depth dose at the intersections of the sagittal plane with the five measured transverse planes. For these same depth doses, results for the mixed beam plan agreed with the sum of the individual depth doses for the bolus ECT and IMXT plans. The six mean measured planar dose distributions were compared with those calculated by the treatment planning system for all modalities. Dose agreement was assessed using the 4% dose difference and 0.2 cm distance to agreement. Results: For the combined high-dose region and low-dose region, pass rates for the parotid and CW plans were 98.7% and 96.2%, respectively, for the bolus ECT plans and 97.9% and 97.4%, respectively, for the mixed beam plans. For the high-dose gradient region, pass rates for the parotid and CW plans were 93.1% and 94

Effect of chest wall radiotherapy in different manners using tissue equivalent bolus on skin and lung of cavia cobayas

International Nuclear Information System (INIS)

Huang Wei; Qu Yaqin; Song Xiangfu; Liu Shixin; Jia Xiaojing; Guo He; Yang Lei

2009-01-01

Objective: To probe the influence of electron beam radiotherapy in different manners using different tissue equivalent boluses on skin and lung. Methods: Adult female cavia cobayas were randomly divided into four groups as control group, half-time with bolus group, half-time with bolus group and without bolus group. Acute-irradiation animal models were established using electron beam in different manners with or without 0.5 cm tissue equivalent bolus. Pathological changes in lung, hair vesicle and fibroblast cell count were analyzed 40 clays after irradiation. Results: The radiation dermatitis in the group with bolus was slighter than that of the group without bolus, but the radiation pneumonia was reverse. With bolus, the radiation dermatitis of haft-time group was slighter than that of full-time group. The injury repair of half-time group was more active than full-time group. Conclusions: The treatment of haft-time bolus could protect lung without serious skin complications. (authors)

The Consideration of Bolus Effects of Games Attached on Lesion area

International Nuclear Information System (INIS)

Park, Ju Young; Ju, Sang Kyu; Park, Young Chul; Han, Young Yi; Shin, Eun Hyuk; Park, Yong Hwan

2004-01-01

The aim of this study is to evaluate the effect of skin dose and PDD by using wounds protecting gauzes or Vaselinespread gauzes. And it was studied that the possibility to substitute custom bolus into gauzes. 4 MV photon (CL600C, varian, US), Polystyrene Phantom (30(W) X 30(L) X 30(H)) with Markus chamber(PTW, US) were used for dose measurement. This study was distinguished natural gauzes and spread over Vaseline gauzes. We gave variety to the gauze thickness at 5, 10 and 15 sheets respectively. For comparison between using bolus and not that, we had used 1.0 cm thickness bolus so that analyzed surface dose and PDD at the same conditions above mentioned. When maximum point was defined as reference point, surface dose was measured as 35% in open beam. When the gauzes were attached to surface as 5, 10 and 15 sheets, surface dose were increased as 69, 80 and 91% respectively according to thickness of gauzes. When spread over Vaseline gauzes were attached to surface as 5, 10 and 15 sheets, surface dose were increased respectively as 98, 100 and 98% according to thickness of gauzes. Also when 0.5 cm bolus and 5 sheets gauzes were composed, surface dose was measured as 98%. The gauzes that were attached to skin surface in radiation therapy had been scattering material and contributed increasing surface dose without variation of percentage depth dose. However, if we want to delivery much dose to skin surface then we have to apply many sheets of gauzes to skin surface. Although we get easy that result by bolus or spread over Vaseline gauzes, we have to revise percentage depth dose at calculation. Therefore, if we find pertinent conditions based on measured data that are considered skin dose and patient setup efficiency, to replace custom bolus with gauzes will be helpful to efficient treatment.

SU-F-T-500: The Effectiveness of a Patient Specific Bolus Made by Using Three-Dimensional Printing Technique in Photon Radiotherapy

International Nuclear Information System (INIS)

Fujimoto, K; Yuasa, Y; Shiinoki, T; Hanazawa, H; Shibuya, K

2016-01-01

Purpose: A commercially available bolus (commercial-bolus) would not completely contact with the irregular shape of a patient’s skin. The purposes of this study were to customize a patient specific three-dimensional (3D) bolus using a 3D printer (3D-bolus) and to evaluate its clinical feasibility for photon radiotherapy. Methods: The 3D-bolus was designed using a treatment planning system (TPS) in DICOM-RT format. To print the 3D bolus, the file was converted into stereolithography format. To evaluate its physical characteristics, plans were created for water equivalent phantoms without the bolus, with the 3D-bolus printed in a flat form, and with the virtual bolus which supposed a commercial-bolus. These plans were compared with the percent depth dose (PDD) measured from the TPS. Furthermore, to evaluate its clinical feasibility, the treatment plans were created for RANDO phantoms without the bolus and with the 3D-bolus which was customized for contacting with the surface of the phantom. Both plans were compared with the dose volume histogram (DVH) of the target volume. Results: In the physical evaluation, dmax of the plan without the bolus, with the 3D-bolus, and with the virtual bolus were 2.2 cm, 1.6 cm, and 1.7 cm, respectively. In the evaluation of clinical feasibility, for the plan without the bolus, Dmax, Dmin, Dmean, D90%, and V90% of the target volume were 102.6 %, 1.6 %, 88.8 %, 57.2 %, and 69.3 %, respectively. By using the 3D-bolus, the prescription dose could be delivered to at least 90 % of the target volume, Dmax, Dmin, Dmean, D90%, and V90% of the target volume were 104.3 %, 91.6 %, 92.1 %, 91.7 %, and 98.0 %, respectively. The 3D-bolus has the potential to be useful for providing effective dose coverage in the buildup region. Conclusion: A 3D-bolus produced using 3D printing technique is comparable to a commercially available bolus.

SU-F-T-500: The Effectiveness of a Patient Specific Bolus Made by Using Three-Dimensional Printing Technique in Photon Radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Fujimoto, K; Yuasa, Y [Department of Radiological Technology, Yamaguchi University Hospital (Japan); Shiinoki, T; Hanazawa, H; Shibuya, K [Department of Radiation Oncology, Graduate school of Medicine, Yamaguchi University (Japan)

2016-06-15

Purpose: A commercially available bolus (commercial-bolus) would not completely contact with the irregular shape of a patient’s skin. The purposes of this study were to customize a patient specific three-dimensional (3D) bolus using a 3D printer (3D-bolus) and to evaluate its clinical feasibility for photon radiotherapy. Methods: The 3D-bolus was designed using a treatment planning system (TPS) in DICOM-RT format. To print the 3D bolus, the file was converted into stereolithography format. To evaluate its physical characteristics, plans were created for water equivalent phantoms without the bolus, with the 3D-bolus printed in a flat form, and with the virtual bolus which supposed a commercial-bolus. These plans were compared with the percent depth dose (PDD) measured from the TPS. Furthermore, to evaluate its clinical feasibility, the treatment plans were created for RANDO phantoms without the bolus and with the 3D-bolus which was customized for contacting with the surface of the phantom. Both plans were compared with the dose volume histogram (DVH) of the target volume. Results: In the physical evaluation, dmax of the plan without the bolus, with the 3D-bolus, and with the virtual bolus were 2.2 cm, 1.6 cm, and 1.7 cm, respectively. In the evaluation of clinical feasibility, for the plan without the bolus, Dmax, Dmin, Dmean, D90%, and V90% of the target volume were 102.6 %, 1.6 %, 88.8 %, 57.2 %, and 69.3 %, respectively. By using the 3D-bolus, the prescription dose could be delivered to at least 90 % of the target volume, Dmax, Dmin, Dmean, D90%, and V90% of the target volume were 104.3 %, 91.6 %, 92.1 %, 91.7 %, and 98.0 %, respectively. The 3D-bolus has the potential to be useful for providing effective dose coverage in the buildup region. Conclusion: A 3D-bolus produced using 3D printing technique is comparable to a commercially available bolus.

SU-C-213-05: Evaluation of a Composite Copper-Plastic Material for a 3D Printed Radiation Therapy Bolus

International Nuclear Information System (INIS)

Vitzthum, L; Ehler, E; Sterling, D; Reynolds, T; Higgins, P; Dusenbery, K

2015-01-01

Purpose: To evaluate a novel 3D printed bolus fabricated from a copper-plastic composite as a thin flexible, custom fitting device that can replicate doses achieved with conventional bolus techniques. Methods: Two models of bolus were created on a 3D printer using a composite copper-PLA/PHA. Firstly, boluses were constructed at thicknesses of 0.4, 0.6 and 0.8 mm. Relative dose measurements were performed under the bolus with an Attix Chamber as well as with radiochromic film. Results were compared to superficial Attix Chamber measurements in a water equivalent material to determine the dosimetric water equivalence of the copper-PLA/PHA plastic. Secondly, CT images of a RANDO phantom were used to create a custom fitting bolus across the anterolateral scalp. Surface dose with the bolus placed on the RANDO phantom was measured with radiochromic film at tangential angles with 6, 10, 10 flattening filter free (FFF) and 18 MV photon beams. Results: Mean surface doses for 6, 10, 10FFF and 18 MV were measured as a percent of Dmax for the flat bolus devices of each thickness. The 0.4 mm thickness bolus was determined to be near equivalent to 2.5 mm depth in water for all four energies. Surface doses ranged from 59–63% without bolus and 85–90% with the custom 0.4 mm copper-plastic bolus relative to the prescribed dose for an oblique tangential beam arrangement on the RANDO phantom. Conclusion: Sub-millimeter thickness, 3D printed composite copper-PLA/PHA bolus can provide a build-up effect equivalent to conventional bolus. At this thickness, the 3D printed bolus allows a level of flexure that may provide more patient comfort than current 3D printing materials used in bolus fabrication while still retaining the CT based custom patient shape. Funding provided by an intra-department grant of the University of Minnesota Department of Radiation Oncology

SU-C-213-05: Evaluation of a Composite Copper-Plastic Material for a 3D Printed Radiation Therapy Bolus

Energy Technology Data Exchange (ETDEWEB)

Vitzthum, L; Ehler, E; Sterling, D; Reynolds, T; Higgins, P; Dusenbery, K [University of Minnesota, Minneapolis, MN (United States)

2015-06-15

Purpose: To evaluate a novel 3D printed bolus fabricated from a copper-plastic composite as a thin flexible, custom fitting device that can replicate doses achieved with conventional bolus techniques. Methods: Two models of bolus were created on a 3D printer using a composite copper-PLA/PHA. Firstly, boluses were constructed at thicknesses of 0.4, 0.6 and 0.8 mm. Relative dose measurements were performed under the bolus with an Attix Chamber as well as with radiochromic film. Results were compared to superficial Attix Chamber measurements in a water equivalent material to determine the dosimetric water equivalence of the copper-PLA/PHA plastic. Secondly, CT images of a RANDO phantom were used to create a custom fitting bolus across the anterolateral scalp. Surface dose with the bolus placed on the RANDO phantom was measured with radiochromic film at tangential angles with 6, 10, 10 flattening filter free (FFF) and 18 MV photon beams. Results: Mean surface doses for 6, 10, 10FFF and 18 MV were measured as a percent of Dmax for the flat bolus devices of each thickness. The 0.4 mm thickness bolus was determined to be near equivalent to 2.5 mm depth in water for all four energies. Surface doses ranged from 59–63% without bolus and 85–90% with the custom 0.4 mm copper-plastic bolus relative to the prescribed dose for an oblique tangential beam arrangement on the RANDO phantom. Conclusion: Sub-millimeter thickness, 3D printed composite copper-PLA/PHA bolus can provide a build-up effect equivalent to conventional bolus. At this thickness, the 3D printed bolus allows a level of flexure that may provide more patient comfort than current 3D printing materials used in bolus fabrication while still retaining the CT based custom patient shape. Funding provided by an intra-department grant of the University of Minnesota Department of Radiation Oncology.

SU-F-T-517: Determining the Tissue Equivalence of a Brass Mesh Bolus in a Reconstructed Chest Wall Irradiation

Energy Technology Data Exchange (ETDEWEB)

Shekel, E; Epstein, D; Levin, D [Dept of radiotherapy, Assuta Medical Centers, Tel Aviv (Israel)

2016-06-15

Purpose: To determine the tissue equivalence of a brass mesh bolus (RPD) in the setting of a reconstructed chest wall irradiation Methods: We measured breast skin dose delivered by a tangential field plan on an anthropomorphic phantom using Mosfet and nanoDot (Landauer) dosimeters in five different locations on the breast. We also measured skin dose using no bolus, 5mm and 10 mm superflab bolus. In the Eclipse treatment planning system (Varian, Palo Alto, CA) we calculated skin dose for different bolus thicknesses, ranging from 0 to 10 mm, in order to evaluate which calculation best matches the brass mesh measurements, as the brass mesh cannot be simulated due to artefacts.Finally, we measured depth dose behavior with the brass mesh bolus to verify that the bolus does not affect the dose to the breast itself beyond the build-up region. Results: Mosfet and nanoDot measurements were consistent with each other.As expected, skin dose measurements with no bolus had the least agreement with Eclipse calculation, while measurements for 5 and 10 mm agreed well with the calculation despite the difficulty in conforming superflab bolus to the breast contour. For the brass mesh the best agreement was for 3 mm bolus Eclipse calculation. For Mosfets, the average measurement was 90.8% of the expected dose, and for nanoDots 88.33% compared to 83.34%, 88.64% and 93.94% (2,3 and 5 mm bolus calculation respectively).The brass mesh bolus increased skin dose by approximately 25% but there was no dose increase beyond the build-up region. Conclusion: Brass mesh bolus is most equivalent to a 3 mm bolus, and does not affect the dose beyond the build-up region. The brass mesh cannot be directly calculated in Eclipse, hence a 3mm bolus calculation is a good reflection of the dose response to the brass mesh bolus.

Effects of a sour bolus on the intramuscular electromyographic (EMG) activity of muscles in the submental region.

Science.gov (United States)

Palmer, Phyllis M; McCulloch, Timothy M; Jaffe, Debra; Neel, Amy T

2005-01-01

A sour bolus has been used as a modality in the treatment of oropharyngeal dysphagia based on the hypothesis that this stimulus provides an effective preswallow sensory input that lowers the threshold required to trigger a pharyngeal swallow. The result is a more immediate swallow onset time. Additionally, the sour bolus may invigorate the oral muscles resulting in stronger contractions during the swallow. The purpose of this investigation was to compare the intramuscular electromyographic activity of the mylohyoid, geniohyoid, and anterior belly of the digastric muscles during sour and water boluses with regard to duration, strength, and timing of muscle activation. Muscle duration, swallow onset time, and pattern of muscle activation did not differ for the two bolus types. Muscle activation time was more tightly approximated across the onsets of the three muscles when a sour bolus was used. A sour bolus also resulted in a stronger muscle contraction as evidenced by greater electromyographic activity. These data support the use of a sour bolus as part of a treatment paradigm.

Soft-robotic esophageal swallowing as a clinically-inspired bolus rheometry technique

International Nuclear Information System (INIS)

Dirven, Steven; Allen, Jacqueline; Xu, Weiliang; Cheng, Leo K

2017-01-01

To investigate the impact of viscosity and peristaltic transport parameters on manometric pressure signatures, a reproducible swallowing process is required. Due to inter- and intra-subject variability from swallow to swallow, the human body does not represent an optimal mechanism for such an investigation. A smooth and continuous swallowing soft-robot has been developed to produce biomimetic swallowing trajectories, and is proposed to operate as a bench-top bolus rheometric investigation method. The method compares conventional viscometry and pressure signature findings from robotic swallowing experiments. The robotic aspect of experimentation involved 450 biomimetic swallows (10 repetitions of 45 unique experiments). The method examined swallowing transport in three dimensions: bolus formulation, peristaltic wavelength, and peristaltic velocity, each of which are known to contribute to safe and effective swallowing in vivo . It is found that the pressure gradients and magnitudes are commensurate with clinical reports on biological swallowing, on the order of 100 mmHg peak, however, the relationship between viscosity and pressure signatures is less clear. Bolus transport cannot be predicted as a function of bolus viscosity alone. Traditional viscometric data at 50 s −1 , as used in clinical practice, may not be a strong indicator of swallow effort, safety, or efficacy in vivo . (paper)

EFFECT OF A BITTER BOLUS ON ORAL, PHARYNGEAL AND ESOPHAGEAL TRANSIT OF HEALTHY SUBJECTS

Directory of Open Access Journals (Sweden)

Leda Maria Tavares ALVES

2013-03-01

Full Text Available Context During swallowing, boluses stimulate sensory receptors of the oral, pharyngeal, laryngeal, and esophageal regions. Sweet and tasteless foods are more acceptable for swallowing than bitter foods. A bitter bolus is unpleasant for most subjects. Our hypothesis was that the ingestion of a bitter bolus might alter the oral behavior, pharyngeal and esophageal transit when compared to a sweet bolus. Objective To evaluate whether the bitter taste of a liquid bolus causes alteration on oral, pharyngeal and/or esophageal transit in normal subjects in comparison with sweet bolus.' Method Scintigraphic evaluation of oral, pharyngeal and esophageal transit was performed in 43 asymptomatic subjects, 22 women and 21 men, ages 23-71 years, without problems with the ingestion of liquid and solid foods, and without digestive, cardiac or neurologic diseases. Each subject swallowed in random sequence and at room temperature 5 mL of a liquid bolus with bitter taste, prepared with 50 mL of water with 2 g of leaves of Peumus boldus, heated until boiling (boldus tea, and 5 mL of a liquid bolus with sweet taste, prepared with 50 mL of water with 3 g of sucrose, both labeled with 37 MBq of technetium phytate (Tc99m. Results There was no difference between the bitter bolus and the sweet bolus in mouth, pharynx and esophageal transit and clearance duration and in the amount of residues. Conclusion A bitter bolus, considered an unpleasant bolus, does not alter the duration of oral, pharyngeal and esophageal phases of swallowing, when compared with a sweet bolus, considered a pleasant bolus. Contexto Durante a deglutição o bolo estimula os receptores sensoriais da boca, faringe, laringe e esôfago. Os alimentos doces e sem gosto são mais aceitáveis para a deglutição do que os alimentos amargos, que tem gosto desagradável para a maioria dos indivíduos. A hipótese destes autores era que a ingestão de um bolo amargo pode alterar o trânsito oral

Sci—Thur AM: YIS - 07: Design and production of 3D printed bolus for electron radiation therapy

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Su, Shiqin [Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia (Canada); Moran, Kathryn [Queen Elizabeth II Health Sciences Centre, Nova Scotia Cancer Centre, Halifax, Nova Scotia (Canada); Robar, James L. [Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia (Canada); Department of Radiation Oncology, Dalhousie University, Halifax, Nova Scotia (Canada)

2014-08-15

This is a proof-of-concept study demonstrating the capacity for modulated electron radiation therapy (MERT) using 3D printed bolus. Previous reports have involved bolus design using an electron pencil beam model and fabrication using a milling machine. In this study, an in-house algorithm is presented that optimizes the dose distribution with regard to dose coverage, conformity and homogeneity within planning target volume (PTV). The algorithm uses calculated result of a commercial electron Monte Carlo dose calculation as input. Distances along ray lines from distal side of 90% isodose to distal surface of PTV are used to estimate the bolus thickness. Inhomogeneities within the calculation volume are accounted for using coefficient of equivalent thickness method. Several regional modulation operators are applied to improve dose coverage and uniformity. The process is iterated (usually twice) until an acceptable MERT plan is realized, and the final bolus is printed using solid polylactic acid. The method is evaluated with regular geometric phantoms, anthropomorphic phantoms and a clinical rhabdomyosarcoma pediatric case. In all cases the dose conformity is improved compared to that with uniform bolus. The printed boluses conform well to the surface of complex anthropomorphic phantoms. For the rhabdomyosarcoma patient, the MERT plan yields a reduction of mean dose by 38.2% in left kidney relative to uniform bolus. MERT using 3D printed bolus appears to be a practical, low cost approach to generating optimized bolus for electron therapy. The method is effective in improving conformity of prescription isodose surface and in sparing immediately adjacent normal tissues.

Sci—Thur AM: YIS - 07: Design and production of 3D printed bolus for electron radiation therapy

International Nuclear Information System (INIS)

Su, Shiqin; Moran, Kathryn; Robar, James L.

2014-01-01

This is a proof-of-concept study demonstrating the capacity for modulated electron radiation therapy (MERT) using 3D printed bolus. Previous reports have involved bolus design using an electron pencil beam model and fabrication using a milling machine. In this study, an in-house algorithm is presented that optimizes the dose distribution with regard to dose coverage, conformity and homogeneity within planning target volume (PTV). The algorithm uses calculated result of a commercial electron Monte Carlo dose calculation as input. Distances along ray lines from distal side of 90% isodose to distal surface of PTV are used to estimate the bolus thickness. Inhomogeneities within the calculation volume are accounted for using coefficient of equivalent thickness method. Several regional modulation operators are applied to improve dose coverage and uniformity. The process is iterated (usually twice) until an acceptable MERT plan is realized, and the final bolus is printed using solid polylactic acid. The method is evaluated with regular geometric phantoms, anthropomorphic phantoms and a clinical rhabdomyosarcoma pediatric case. In all cases the dose conformity is improved compared to that with uniform bolus. The printed boluses conform well to the surface of complex anthropomorphic phantoms. For the rhabdomyosarcoma patient, the MERT plan yields a reduction of mean dose by 38.2% in left kidney relative to uniform bolus. MERT using 3D printed bolus appears to be a practical, low cost approach to generating optimized bolus for electron therapy. The method is effective in improving conformity of prescription isodose surface and in sparing immediately adjacent normal tissues

Three-dimensional printer-aided casting of soft, custom silicone boluses (SCSBs) for head and neck radiation therapy.

Science.gov (United States)

Chiu, Tsuicheng; Tan, Jun; Brenner, Mathew; Gu, Xuejun; Yang, Ming; Westover, Kenneth; Strom, Tobin; Sher, David; Jiang, Steve; Zhao, Bo

Custom tissue compensators provide dosimetric advantages for treating superficial or complex anatomy, but currently available fabrication technology is expensive or impractical for most clinical operations and yields compensators that are difficult for patients to tolerate. We aimed to develop an inexpensive, clinically feasible workflow for generating patient-specific, soft, custom silicone boluses (SCSBs) for head-and-neck (HN) radiation therapy. We developed a method using 3-dimensional printed parts for generating SCSBs for the treatment of HN cancers. The clinical workflow for generation of SCSBs was characterized inclusive of patient simulation to treatment in terms of resource time and cost. Dosimetric properties such as percentage depth dose and dose profiles were measured for SCSBs using GaF films. Comprehensive measurements were also conducted on an HN phantom. SCSBs were generated and used for electron or photon based radiation treatments of 7 HN patients with lesions at nose, cheek, eye, or ears. In vivo dose measurements with optically simulated luminescence dosimeters were performed. Total design and fabrication time from patient simulation to radiation treatment start required approximately 1 week, with fabrication constituting 1 to 2 working days depending on bolus surface area, volume, and complexity. Computed tomography and dosimetric properties of the soft bolus were similar to water. In vivo dose measurements on 7 treated patients confirmed that the dose deposition conformed to planned doses. Material costs were lower than currently available hard plastic boluses generated with 3-dimensional printing technology. All treated patients tolerated SCSBs for the duration of therapy. Generation and use of SCSBs for clinical use is feasible and effective for the treatment of HN cancers. Copyright © 2017 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Development of a bolus injection system for regional deposition studies of nanoparticles in the human respiratory system

International Nuclear Information System (INIS)

Koujalagi, V; Semple, S; Ayres, J G; Ramesh, S L; Gunarathne, G P P

2009-01-01

This study presents the work carried out in developing a precision bolus injection system in order to understand the regional deposition of nanoparticles (NP) in human lung. A real-time control system has been developed that is capable of storing graphite NP, assessing human breathing pattern and delivering a bolus of the stored NP at a pre-determined instance of the inhalation phase of breathing. This will form the basis for further development of a system to deliver radioactive nanoparticles to enable 3-dimensional lung imaging using techniques such as positron emission tomography (PET). The system may then be used to better understand the actual regional deposition in human lung, which could validate or challenge the current computational lung models such as that published by the International Commission for Radiation Protection (ICRP-1994). A dose related response to inhaled PM can possibly be shown, which can be used to review the current workplace exposure limits (WELs).

Development of a bolus injection system for regional deposition studies of nanoparticles in the human respiratory system

Science.gov (United States)

Koujalagi, V.; Ramesh, S. L.; Gunarathne, G. P. P.; Semple, S.; Ayres, J. G.

2009-02-01

This study presents the work carried out in developing a precision bolus injection system in order to understand the regional deposition of nanoparticles (NP) in human lung. A real-time control system has been developed that is capable of storing graphite NP, assessing human breathing pattern and delivering a bolus of the stored NP at a pre-determined instance of the inhalation phase of breathing. This will form the basis for further development of a system to deliver radioactive nanoparticles to enable 3-dimensional lung imaging using techniques such as positron emission tomography (PET). The system may then be used to better understand the actual regional deposition in human lung, which could validate or challenge the current computational lung models such as that published by the International Commission for Radiation Protection (ICRP-1994). A dose related response to inhaled PM can possibly be shown, which can be used to review the current workplace exposure limits (WELs).

In Silico Assessment of Literature Insulin Bolus Calculation Methods Accounting for Glucose Rate of Change.

Science.gov (United States)

Cappon, Giacomo; Marturano, Francesca; Vettoretti, Martina; Facchinetti, Andrea; Sparacino, Giovanni

2018-05-01

The standard formula (SF) used in bolus calculators (BCs) determines meal insulin bolus using "static" measurement of blood glucose concentration (BG) obtained by self-monitoring of blood glucose (SMBG) fingerprick device. Some methods have been proposed to improve efficacy of SF using "dynamic" information provided by continuous glucose monitoring (CGM), and, in particular, glucose rate of change (ROC). This article compares, in silico and in an ideal framework limiting the exposition to possibly confounding factors (such as CGM noise), the performance of three popular techniques devised for such a scope, that is, the methods of Buckingham et al (BU), Scheiner (SC), and Pettus and Edelman (PE). Using the UVa/Padova Type 1 diabetes simulator we generated data of 100 virtual subjects in noise-free, single-meal scenarios having different preprandial BG and ROC values. Meal insulin bolus was computed using SF, BU, SC, and PE. Performance was assessed with the blood glucose risk index (BGRI) on the 9 hours after meal. On average, BU, SC, and PE improve BGRI compared to SF. When BG is rapidly decreasing, PE obtains the best performance. In the other ROC scenarios, none of the considered methods prevails in all the preprandial BG conditions tested. Our study showed that, at least in the considered ideal framework, none of the methods to correct SF according to ROC is globally better than the others. Critical analysis of the results also suggests that further investigations are needed to develop more effective formulas to account for ROC information in BCs.

The Interactive Effect of Diabetes Family Conflict and Depression on Insulin Bolusing Behaviors for Youth.

Science.gov (United States)

Maliszewski, Genevieve; Patton, Susana R; Midyett, L Kurt; Clements, Mark A

2017-05-01

Adherence to type 1 diabetes management declines as children enter adolescence. For youth, psychosocial variables including mood and interpersonal relationships play a large role in diabetes maintenance. The current study assessed the unique and interactive roles diabetes family conflict and depression have on insulin bolusing behaviors for youth ages 10-16 years. Ninety-one youth-parent dyads completed a survey assessing family conflict and depression. Mean daily blood glucose levels, mealtime insulin bolus scores ( BOLUS), and glycated hemoglobin (HbA1c) were collected from the medical record as outcome variables. Parent-reported diabetes-related family conflict and youths' endorsed depression both significantly predicted insulin bolusing behavior, R 2 = .13, F(2, 88) = 6.66, P family conflict and youth depression played a significant role in youths' bolusing behaviors, above and beyond that which was predicted by conflict and depression separately, R 2 = .18, F change (1, 87) = 4.63, P family conflict, while there was no change in BOLUS scores among depressed youth living in families reporting less conflict. Findings underscore the importance of screening for depression and family conflict in youth experiencing or at risk for poor adherence to mealtime insulin and higher HbA1c levels.

Pre-pharyngeal swallow effects of recurrent laryngeal nerve lesion on bolus shape and airway protection in an infant pig model

Science.gov (United States)

Gould, Francois D. H.; Yglesias, B.; Ohlemacher, J.; German, R. Z.

2016-01-01

Recurrent laryngeal nerve (RLN) damage in infants leads to increased dysphagia and aspiration pneumonia. Recent work has shown that intra oral transport and swallow kinematics change following RLN lesion, suggesting potential changes in bolus formation prior to the swallow. In this study we used geometric morphometrics to understand the effect of bolus shape on penetration and aspiration in infants with and without RLN lesion. We hypothesized 1) that geometric bolus properties are related to airway protection outcomes and 2) that in infants with RLN lesion, the relationship between geometric bolus properties and dysphagia is changed. In five infant pigs, dysphagia in 188 swallows was assessed using the Infant Mammalian Penetration Aspiration Score (IMPAS). Using images from high-speed VFSS, bolus shape, bolus area, and tongue outline were quantified digitally. Bolus shape was analyzed using elliptical Fourier analysis, and tongue outline using polynomial curve fitting. Despite large inter-individual differences, significant within individual effects of bolus shape and bolus area on airway protection exist. The relationship between penetration-aspiration score and both bolus area and shape changed post lesion. Tongue shape differed between pre and post lesion swallows, and between swallows with different IMPAS scores. Bolus shape and area affect airway protection outcomes. RLN lesion changes that relationship, indicating that proper bolus formation and control by the tongue requires intact laryngeal sensation. The impact of RLN lesion on dysphagia is pervasive. PMID:27873091

Custom bolus of hydrogel: dosimetric characterization, clinical use and placement uncertainties; Bolus de compensación personalizado de hidrogel: Caracterización radiológica, uso clínico e incertidumbre de colocación

Energy Technology Data Exchange (ETDEWEB)

Pérez-García, H.; Antón, D.; Miguel, D.; Ángel del Castillo, D.; Alonso, D.; De Frutos, J.; Pérez, C.

2017-11-01

When using electron beams over irregular surfaces it shows remarkable dose heterogeneity in target tissue, the use of a hydrogel bolus by Varihesive® ConvaTec as a custom bolus is proposed to compensate this effect. Radiological characterization is carried out comparing hydrogel with water by a CT study and by measuring percentage depth dose for electron beams. The dosimetric impact due to the uncertainty of bolus placement is quantitatively evaluated and it is concluded that the use of hydrogel is an acceptable solution as compensation bolus with radiological properties similar to water. [Spanish] La incidencia de un campo de electrones en una superficie irregular produce distribuciones heterogéneas de dosis. En este trabajo se propone el uso de un bolus personalizado de hidrogel Varihesive® de ConvaTec para compensar dichas irregularidades. El hidrogel se caracteriza radiológicamente comparándolo con agua mediante una adquisición TC y se obtiene el porcentaje de dosis en profundidad para campos de electrones. Se evalúa cuantitativamente el impacto dosimétrico debido a la incertidumbre de colocación y se concluye que el uso de hidrogel resulta una solución aceptable como bolus de compensación con propiedades radiológicas similares al agua.

Endoscopic evaluation of food bolus formation and its relationship with the number of chewing cycles.

Science.gov (United States)

Fukatsu, H; Nohara, K; Kotani, Y; Tanaka, N; Matsuno, K; Sakai, T

2015-08-01

It is known that solid food is transported to the pharynx actively in parallel to it being crushed by chewing and mixed with saliva in the oral cavity. Therefore, food bolus formation should be considered to take place from the oral cavity to the pharynx. In previous studies, the chewed food was evaluated after the food had been removed from the oral cavity. However, it has been pointed out that spitting food out of the oral cavity interferes with natural food bolus formation. Therefore, we observed food boluses immediately before swallowing using an endoscope to establish a method to evaluate the food bolus-forming function, and simultaneously performed endoscopic evaluation of food bolus formation and its relationship with the number of chewing cycles. The subject was inserted the endoscope nasally and instructed to eat two coloured samples of boiled rice simultaneously in two ingestion conditions ('as usual' and 'chewing well'). The condition of the food bolus was graded into three categories for each item of grinding, mixing and aggregation and scored 2, 1 and 0. The score of aggregation was high under both ingestion conditions. The scores of grinding and mixing tended to be higher in subjects with a high number of chewing cycles, and the score of aggregation was high regardless of the number of chewing cycles. It was suggested that food has to be aggregated, even though the number of chewing cycles is low and the food is not ground or mixed for a food bolus to reach the swallowing threshold. © 2015 John Wiley & Sons Ltd.

'Chasing the Dragon' - imaging of heroin inhalation leukoencephalopathy

Energy Technology Data Exchange (ETDEWEB)

Hagel, J. [Vancouver General Hospital, Dept. of Radiology, Vancouver, British Columbia (Canada)]. E-mail: jeff_hagel@hotmail.com; Andrews, G. [UBC Hospital, Dept. of Radiology, Vancouver, British Columbia (Canada); Vertinsky, T. [Vancouver General Hospital, Dept. of Radiology, Vancouver, British Columbia (Canada); Heran, M.K.S. [Vancouver General Hospital, Div. of Neuroradiology, Vancouver, British Columbia (Canada); Keogh, C. [BC Cancer Agency, Dept. of Radiology, Vancouver, British Columbia (Canada)

2005-10-15

'Chasing the dragon' refers to the inhalation of heroin pyrolysate vapors produced when the freebase form of heroin is heated. Inhalation of these vapors can result in a rare toxic spongiform leukoencephalopathy. The patients may progress through 3 defined clinical stages, with one-quarter reaching the terminal stage, which invariably leads to death. Imaging and, in particular, magnetic resonance imaging (MRI) demonstrates white matter findings that are felt to be specific for this entity and essential in its early diagnosis. We present the typical imaging findings in a pictorial essay format, using images taken from 9 patients who presented within an 18-month period at UBC-affiliated hospitals. These findings include low computed tomography (CT) attenuation and high T2 MRI signal most commonly in the posterior cerebral and cerebellar white matter, cerebellar peduncles, splenium of the corpus callosum, and posterior limb of the internal capsules. In addition, there is often selective, symmetric involvement of the corticospinal tract, the medial lemniscus, and the tractus solitarius. We also present the variable diffusion-weighted imaging arid apparent diffusion coefficient findings from 4 of our patients, which to our knowledge, have not been described in the literature. (author)

Cineradiography of the liquid bolus swallow. A study of the speed ot the bolus and peristaltic wave and of movement of the hyoid bone, larynx, and epiglottis

International Nuclear Information System (INIS)

Sundgren, P.

1991-01-01

In the evaluation of the dysphagic patient, radiology is crucial as a technique for monitoring morphology and function. In particular, high-speed cineradiography can reveal a variety of pharyngeal dysfunctions. However, in the literature and in practice the difference between normal and abnormal function is not always clear. This monography is based on high-speed cineradiographies of swallowing in 75 non-dysphagic volunteers and in 189 dysphagic patients. The purpose was to study whether differences in bolus volumes, patient position, age and gender had any effects on the following parameters: the speed of the peristaltic wave and apex of the liquid barium bolus, the length of movement and the movement pattern of the hyoid bone and larynx, and epiglottic function. The study disclosed that the speed of the bolus, the anterior-superior movement and net movement of the hyoid bone increased significantly with larger bolus volumes. The position of the individual in relation to gravity significantly influenced the speed of peristalsis. In most of the measured parameters there were no differences between non-dysphagic and dysphagic individuals expect for differences in the intrapersonal variations and in the anterior-superior movement of the hyoid bone. In patients with pharyngeal dysfunction the initial stage of the elevation of the larynx was significantly lower than in patients without dysfunction. The approximation of the thyroid cartilage to the hyoid bone was significantly greater in individuals with normal epiglottic function than in those with epiglottic dysmobility. It is suggested that abnormal speed of peristalsis may be a mild form of dysfunction. Measurements of the aforementioned speed and movements can be done if bolus volume, age and position of the patient, film speed and magnifications factors are known. Hypotheses concerning epiglottic function and central control of swallowing are proposed. (au)

Use of a marshmallow bolus for evaluating lower esophageal mucosal rings.

Science.gov (United States)

Ott, D J; Kelley, T F; Chen, M Y; Gelfand, D W; Wu, W C

1991-07-01

Sixty-three patients (35 women, 28 men; mean age 55 yr) with lower esophageal mucosal ring shown radiographically were examined with a semi-solid bolus consisting of a portion of a standard marshmallow. The most common symptom was dysphagia, present in 46 (73%) patients. Impaction of the marshmallow bolus by the ring occurred in 40 (63%) of the 63 patients, and produced symptoms in 27 (68%) of these 40 patients. Nine (14%) rings were detected radiographically only with a solid bolus; eight of these patients had dysphagia and seven rings were 20 mm or less in caliber. Impaction related to ring caliber, and was found in all 17 (100%) rings that were 13 mm or less in diameter, in 17/24 (71%) 14- to 19-mm rings, and in 6/22 (27%) rings 20 mm or more in caliber. Endoscopy in 23 patients detected 16 (70%) rings, and also depended on ring caliber: less than or equal to 13 mm, 6/6 (100%); 14-19 mm, 5/9 (56%); greater than or equal to 20 mm, 5/8 (63%). Marshmallow impaction occurred in 17 (74%) of 23 patients who had endoscopy; three of the 23 patients had normal endoscopy. In conclusion, radiographic examination supplemented by the use of a marshmallow bolus best detects lower esophageal mucosal ring.

The impact of mastication, salivation and food bolus formation on salt release during bread consumption.

Science.gov (United States)

Tournier, Carole; Grass, Manon; Septier, Chantal; Bertrand, Dominique; Salles, Christian

2014-11-01

Health authorities recommend higher fibre and lower salt content in bread products. However, these basic ingredients of bread composition are multifunctional, and important changes in their content influence the texture, flavour and acceptability of the product. This study was designed to investigate the link between oral processing, bolus formation and sodium release during the consumption of four different breads that varied in composition and structure. Chewing behaviour was determined by surface electromyography, and salivation was quantified from the water content of the boluses collected. The kinetics of bread degradation during food bolus formation was characterised by measuring the bolus heterogeneity by texture image analysis, and sodium release into the saliva was quantified. Mastication and salivation varied between products and between subjects, thus highlighting different bolus formation strategies. In vivo salt release was mainly explained by mastication parameters. The initial slope of sodium release increased when the chewing muscles' activity increased, and the maximum sodium concentration was reached later when more masticatory cycles were required to reach the swallowing point.

The CHilean Automatic Supernova sEarch (CHASE)

Science.gov (United States)

Pignata, G.; Maza, J.; Hamuy, M.; Antezana, R.; Gonzales, L.

2009-05-01

One of the most important challenges in modern cosmology will be to figure out the origin of the dark energy, to measure its equation of state and the time rate with which it changes (described by parameters w and w'). The measurement of these parameters will require high levels of accuracy in the Supernova (SN) Type Ia distances and various sources of systematic error such as reddening corrections and possible evolution in the SNcharacteristics which could couple with redshift and mimic the cosmological signal of interest. Fortunately, these concerns can be fully addressed through the comprehensive study of SNe in the local (z < 0.05) universe. Although Type II plateau SNe are not as luminous as SNe Ia, they afford two important, independent routes to cosmological distances using the Expanding Photosphere Method and the Standardized Candle Method. To assess the performance of these techniques a nearby sample of Type II SNe is necessary. With the purpose of addressing these issues the Millennium Center for Supernova Studies (MCSS) is teaming up with the Carnegie Supernova Project (CSP) to carry out an optical and near infrared (photometry, spectroscopy and polarimetry) follow up of nearby SNe. Unfortunately, the majority of the SNe observed by the MCSS and the CSP are discovered by searches carried out from the northern hemisphere. This entails a number of observational difficulties, in particular, it reduces the number of SNe for which the follow-up starts at very early epochs. The aim of the CHASE project is to remove this search bias by discovering young Southern SNe that will be extensively observed by the MCSS and the CSP. In the first nine-months of operation, CHASE has discovered two SNe: SN007oc (CBET 1114) and SN007pl (CBET 1130), thus demonstrating the feasibility of the survey.

Performance of a glucose meter with a built-in automated bolus calculator versus manual bolus calculation in insulin-using subjects.

Science.gov (United States)

Sussman, Allen; Taylor, Elizabeth J; Patel, Mona; Ward, Jeanne; Alva, Shridhara; Lawrence, Andrew; Ng, Ronald

2012-03-01

Patients consider multiple parameters in adjusting prandial insulin doses for optimal glycemic control. Difficulties in calculations can lead to incorrect doses or induce patients to administer fixed doses, rely on empirical estimates, or skip boluses. A multicenter study was conducted with 205 diabetes subjects who were on multiple daily injections of rapid/ short-acting insulin. Using the formula provided, the subjects manually calculated two prandial insulin doses based on one high and one normal glucose test result, respectively. They also determined the two doses using the FreeStyle InsuLinx Blood Glucose Monitoring System, which has a built-in, automated bolus calculator. After dose determinations, the subjects completed opinion surveys. Of the 409 insulin doses manually calculated by the subjects, 256 (63%) were incorrect. Only 23 (6%) of the same 409 dose determinations were incorrect using the meter, and these errors were due to either confirmed or potential deviations from the study instructions by the subjects when determining dose with meter. In the survey, 83% of the subjects expressed more confidence in the meter-calculated doses than the manually calculated doses. Furthermore, 87% of the subjects preferred to use the meter than manual calculation to determine prandial insulin doses. Insulin-using patients made errors in more than half of the manually calculated insulin doses. Use of the automated bolus calculator in the FreeStyle InsuLinx meter minimized errors in dose determination. The patients also expressed confidence and preference for using the meter. This may increase adherence and help optimize the use of mealtime insulin. © 2012 Diabetes Technology Society.

Characterization of swallow modulation in response to bolus volume in healthy subjects accounting for catheter diameter.

Science.gov (United States)

Ferris, Lara; Schar, Mistyka; McCall, Lisa; Doeltgen, Sebastian; Scholten, Ingrid; Rommel, Nathalie; Cock, Charles; Omari, Taher

2018-06-01

Characterization of the pharyngeal swallow response to volume challenges is important for swallowing function assessment. The diameter of the pressure-impedance recording catheter may influence these results. In this study, we captured key physiological swallow measures in response to bolus volume utilizing recordings acquired by two catheters of different diameter. Ten healthy adults underwent repeat investigations with 8- and 10-Fr catheters. Liquid bolus swallows of volumes 2.5, 5, 10, 20, and 30 mL were recorded. Measures indicative of distension, contractility, and flow timing were assessed. Pressure-impedance recordings with pressure-flow analysis were used to capture key distension, contractility, and pressure-flow timing parameters. Larger bolus volumes increased upper esophageal sphincter distension diameter (P < .001) and distension pressures within the hypopharynx and upper esophageal sphincter (P < .05). Bolus flow timing measures were longer, particularly latency of bolus propulsion ahead of the pharyngeal stripping wave (P < .001). Use of a larger-diameter catheter produced higher occlusive pressures, namely upper esophageal sphincter basal pressure (P < .005) and upper esophageal sphincter postdeglutitive pressure peak (P < .001). The bolus volume swallowed changed measurements indicative of distension pressure, luminal diameter, and pressure-flow timing; this is physiologically consistent with swallow modulation to accommodate larger, faster-flowing boluses. Additionally, catheter diameter predominantly affects lumen occlusive pressures. Appropriate physiological interpretation of the pressure-impedance recordings of pharyngeal swallowing requires consideration of the effects of volume and catheter diameter. NA. Laryngoscope, 128:1328-1334, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Pilots' Attention Distributions Between Chasing a Moving Target and a Stationary Target.

Science.gov (United States)

Li, Wen-Chin; Yu, Chung-San; Braithwaite, Graham; Greaves, Matthew

2016-12-01

Attention plays a central role in cognitive processing; ineffective attention may induce accidents in flight operations. The objective of the current research was to examine military pilots' attention distributions between chasing a moving target and a stationary target. In the current research, 37 mission-ready F-16 pilots participated. Subjects' eye movements were collected by a portable head-mounted eye-tracker during tactical training in a flight simulator. The scenarios of chasing a moving target (air-to-air) and a stationary target (air-to-surface) consist of three operational phases: searching, aiming, and lock-on to the targets. The findings demonstrated significant differences in pilots' percentage of fixation during the searching phase between air-to-air (M = 37.57, SD = 5.72) and air-to-surface (M = 33.54, SD = 4.68). Fixation duration can indicate pilots' sustained attention to the trajectory of a dynamic target during air combat maneuvers. Aiming at the stationary target resulted in larger pupil size (M = 27,105, SD = 6565), reflecting higher cognitive loading than aiming at the dynamic target (M = 23,864, SD = 8762). Pilots' visual behavior is not only closely related to attention distribution, but also significantly associated with task characteristics. Military pilots demonstrated various visual scan patterns for searching and aiming at different types of targets based on the research settings of a flight simulator. The findings will facilitate system designers' understanding of military pilots' cognitive processes during tactical operations. They will assist human-centered interface design to improve pilots' situational awareness. The application of an eye-tracking device integrated with a flight simulator is a feasible and cost-effective intervention to improve the efficiency and safety of tactical training.Li W-C, Yu C-S, Braithwaite G, Greaves M. Pilots' attention distributions between chasing a moving target and a stationary target. Aerosp Med

Cryptic sexual conflict in gift-giving insects: chasing the chase-away.

Science.gov (United States)

Sakaluk, Scott K; Avery, Rachel L; Weddle, Carie B

2006-01-01

The chase-away model of sexual selection posits that elaborate male sexual displays arise because they exploit preexisting biases in females' sensory systems and induce females to mate in a suboptimal manner. An essential element of this hypothesis is that such manipulation should quickly lead to female resistance to male displays. Nuptial food gifts may be a frequent conduit by which males attempt to influence the mating behavior of females against females' own reproductive interests. In decorated crickets Gryllodes sigillatus, such inducements come in the form of a spermatophylax, a gelatinous mass forming part of the male's spermatophore and consumed by the female after mating. We conducted experiments in which spermatophylaxes obtained from male G. sigillatus were offered as novel food gifts to females of a non-gift-giving species (Acheta domesticus) having no evolutionary history of spermatophylax consumption. Female A. domesticus that were allowed to consume the spermatophylax took significantly longer to remate than when given no such opportunity. In contrast, when female G. sigillatus were prevented from consuming their partners' nuptial gifts, there was no difference in their propensity to remate relative to females permitted to consume a food gift after mating. These results suggest that the spermatophylax synthesized by male G. sigillatus contains substances designed to inhibit the sexual receptivity of their mates but that female G. sigillatus have evolved reduced responsiveness to these substances.

Comparison of Insulin Detemir and Insulin Glargine for Hospitalized Patients on a Basal-Bolus Protocol

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Sondra Davis

2017-04-01

Full Text Available BACKGROUND: The primary purpose of this study is to determine whether insulin detemir is equivalent to insulin glargine in controlling hyperglycemia for the adult hospitalized patient on a basal-bolus treatment regimen. METHODS: A retrospective study was conducted at two acute care hospitals within the same health system. Patients from both facilities who were initiated on a basal-bolus subcutaneous insulin regimen were included in the study. The basal-bolus regimen consisted of three components: basal, bolus, and corrective insulin with only the data from the first seven days analyzed. Once the basal-bolus protocol was initiated, all previous glycemic agents were discontinued. The target glycemic goal of the study was 100–180 mg/dL. RESULTS: In both groups, 50% of the patients had achieved the target glycemic control goal (100–180 mg/dL by day 2 (p = 0.3. However, on the seventh or last day of basal-bolus treatment, whichever came first, 36.36% of patients receiving insulin detemir (n = 88 achieved the blood glucose reading goal compared to 52.00% in patients receiving insulin glargine (n = 100 (p = 0.03. This corresponded to an adjusted odds ratio of 2.12 (1.08 to 4.15, p = 0.03. The adjusting variables were provider type, whether the patient was hospitalized within 30 days prior and diagnosis of stroke. The mean blood glucose readings for the insulin glargine and the insulin detemir groups while on basal-bolus therapy were 200 mg/dL and 215 mg/dL, respectively (p = 0.05. The total number of blood glucose readings less than 70 mg/dL and less than 45 mg/dL was very low and there were no differences in number of episodes with hypoglycemia between the two groups. CONCLUSION: There was not a statistical difference between the two groups at 2 days, however there was on the seventh day or the last day of basal-bolus treatment. There were nonsignificant hypoglycemia events between basal insulin groups and the results for the last or seventh day

Triphasic contrast enhanced CT simulation with bolus tracking for pancreas SBRT target delineation.

Science.gov (United States)

Godfrey, Devon J; Patel, Bhavik N; Adamson, Justus D; Subashi, Ergys; Salama, Joseph K; Palta, Manisha

Bolus-tracked multiphasic contrast computed tomography (CT) is often used in diagnostic radiology to enhance the visibility of pancreas tumors, but is uncommon in radiation therapy pancreas CT simulation, and its impact on gross tumor volume (GTV) delineation is unknown. This study evaluates the lesion conspicuity and consistency of pancreas stereotactic body radiation therapy (SBRT) GTVs contoured in the different contrast phases of triphasic CT simulation scans. Triphasic, bolus-tracked planning CT simulation scans of 10 consecutive pancreas SBRT patients were acquired, yielding images of the pancreas during the late arterial (LA), portal venous (PV), and either the early arterial or delayed phase. GTVs were contoured on each phase by a gastrointestinal-specialized radiation oncologist and reviewed by a fellowship-trained abdominal radiologist who specializes in pancreatic imaging. The volumes of the registered GTVs, their overlap ratio, and the 3-dimensional margin expansions necessary for each GTV to fully encompass GTVs from the other phases were calculated. The contrast difference between tumor and normal pancreas was measured, and 2 radiation oncologists rank-ordered the phases according to their value for the lesion-contouring task. Tumor-to-pancreas enhancement was on average much larger for the LA and PV than the delayed phase or early arterial phases; the LA and PV phases were also consistently preferred by the radiation oncologists. Enhancement differences among the phases resulted in highly variable GTV volumes with no observed trends. Overlap ratios ranged from 18% to 75% across all 3 phases, improving to 43% to 91% when considering only the preferred LA and PV phases. GTV expansions necessary to encompass all GTVs ranged from 0.3 to 1.8 cm for all 3 phases, improving slightly to 0.1 to 1.4 cm when considering just the LA and PV phases. For pancreas SBRT, we recommend combining the GTVs from a multiphasic CT simulation with bolus-tracking, including

Development of test bolus tracking method and usefulness in coronary CT angiography

International Nuclear Information System (INIS)

Yamaguchi, Takayoshi; Takahashi, Daichi

2009-01-01

The test bolus tracking (TBT) method is a new injection method of contrast medium that we developed. The TBT method is an injection technique that continuously performs the test bolus injection and the main bolus injection, such that the best acquisition of scan timing and the improvement of examination efficiency can be expected. We compared the TBT method and the test injection method by coronary CT angiography. The results demonstrated that the contrast enhancement of the coronary arteries was high and the variation of the CT value was also small in the TBT method. When the scan timing expected by the TI method and the TBT method were compared, it was different of two seconds or more by the case with 43%. However, the variation of CT value was small for the TBT method in these cases. Therefore, the TBT method is a very useful method for coronary CT angiography (CCTA). (author)

Evaluation of various boluses in dose distribution for electron therapy of the chest wall with an inward defect

Science.gov (United States)

Mahdavi, Hoda; Jabbari, Keyvan; Roayaei, Mahnaz

2016-01-01

Delivering radiotherapy to the postmastectomy chest wall can be achieved using matched electron fields. Surgical defects of the chest wall change the dose distribution of electrons. In this study, the improvement of dose homogeneity using simple, nonconformal techniques of thermoplastic bolus application on a defect is evaluated. The proposed phantom design improves the capability of film dosimetry for obtaining dose profiles of a patient's anatomical condition. A modeled electron field of a patient with a postmastectomy inward surgical defect was planned. High energy electrons were delivered to the phantom in various settings, including no bolus, a bolus that filled the inward defect (PB0), a uniform thickness bolus of 5 mm (PB1), and two 5 mm boluses (PB2). A reduction of mean doses at the base of the defect was observed by any bolus application. PB0 increased the dose at central parts of the defect, reduced hot areas at the base of steep edges, and reduced dose to the lung and heart. Thermoplastic boluses that compensate a defect (PB0) increased the homogeneity of dose in a fixed depth from the surface; adversely, PB2 increased the dose heterogeneity. This study shows that it is practical to investigate dose homogeneity profiles inside a target volume for various techniques of electron therapy. PMID:27051169

Engaging Experiential Service Learning through a Co-Curricular Club: The Chase Charlie Races

Science.gov (United States)

Judge, Lawrence W.; Pierce, David; Petersen, Jeffrey; Bellar, David; Wanless, Elizabeth; Gilreath, Erin; Simon, Laura

2011-01-01

The efficacy of the "Chase Charlie Races" (an experiential learning activity) was demonstrated via program assessment. This was achieved via post-event evaluations of race participants and student club members, and with fitness assessments of 76 elementary students who participated in an eight-week training program. Paired sample t-tests revealed…

Development of a universal dual-bolus injection scheme for the quantitative assessment of myocardial perfusion cardiovascular magnetic resonance

Directory of Open Access Journals (Sweden)

Alfakih Khaled

2011-05-01

Full Text Available Abstract Background The dual-bolus protocol enables accurate quantification of myocardial blood flow (MBF by first-pass perfusion cardiovascular magnetic resonance (CMR. However, despite the advantages and increasing demand for the dual-bolus method for accurate quantification of MBF, thus far, it has not been widely used in the field of quantitative perfusion CMR. The main reasons for this are that the setup for the dual-bolus method is complex and requires a state-of-the-art injector and there is also a lack of post processing software. As a solution to one of these problems, we have devised a universal dual-bolus injection scheme for use in a clinical setting. The purpose of this study is to show the setup and feasibility of the universal dual-bolus injection scheme. Methods The universal dual-bolus injection scheme was tested using multiple combinations of different contrast agents, contrast agent dose, power injectors, perfusion sequences, and CMR scanners. This included 3 different contrast agents (Gd-DO3A-butrol, Gd-DTPA and Gd-DOTA, 4 different doses (0.025 mmol/kg, 0.05 mmol/kg, 0.075 mmol/kg and 0.1 mmol/kg, 2 different types of injectors (with and without "pause" function, 5 different sequences (turbo field echo (TFE, balanced TFE, k-space and time (k-t accelerated TFE, k-t accelerated balanced TFE, turbo fast low-angle shot and 3 different CMR scanners from 2 different manufacturers. The relation between the time width of dilute contrast agent bolus curve and cardiac output was obtained to determine the optimal predefined pause duration between dilute and neat contrast agent injection. Results 161 dual-bolus perfusion scans were performed. Three non-injector-related technical errors were observed (1.9%. No injector-related errors were observed. The dual-bolus scheme worked well in all the combinations of parameters if the optimal predefined pause was used. Linear regression analysis showed that the optimal duration for the predefined

Efficacy study of Styplon Vet Bolus as supportive therapy in management of hemorrhagic conditions of ruminants

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B R Ravikumar

Full Text Available On-field trial was conducted in dairy animals to evaluate efficacy of Styplon Vet Bolus (M/s Himalaya Drug Company, Banglore, India as supportive therapy in management of hemorrhagic conditions (Hematuria, hemoagalectia, bleeding wounds, uterine bleeding and epistaxis of ruminants. Styplon Vet 1-2 boli twice daily was administered to cows and buffaloes, and ½ bolus twice daily for sheep till they recover clinically. The results indicated that Styplon Vet Bolus is a safe and effective styptic in ruminants. [Vet World 2009; 2(12.000: 470-471

21 CFR 520.1802b - Piperazine-carbon disulfide complex boluses.

Science.gov (United States)

2010-04-01

...) per 500 pounds body weight; removal of large strongyles, pinworms, and bots, 1 bolus per 250 pounds...), large strongyles (Strongylus spp.) bots (Gastrophilus spp.), small strongyles, and pinworms (Oxyuris...

Dual-phase helical CT using bolus triggering technique: optimization of transition time

International Nuclear Information System (INIS)

Choi, Young Ho; Kim, Tae Kyoung; Park, Byung Kwan; Koh, Young Hwan; Han, Joon Koo; Choi, Byung Ihn

1999-01-01

To optimize the transition time between the triggering point in monitoring scanning and the initiation of diagnostic hepatic arterial phase (HAP) scanning in hepatic spiral CT, using a bolus triggering technique. One hundred consecutive patients with focal hepatic lesion were included in this study. Patients were randomized into two groups. Transition times of 7 and 11 seconds were used in group 1 and 2, respectively. In all patients, bolus triggered HAP spiral CT was obtained using a semi-automatic bolus tracking program after the injection of 120mL of non-ionic contrast media at a rate of 3mL/sec. When aortic enhancement reached 90 HU, diagnostic HAP scanning began after a given transition time. From images of group 1 and group 2, the degree of parenchymal enhancement of the liver and tumor-to-liver attenuation difference were measured. Also, for qualitative analysis, conspicuity of the hepatic artery and hypervascular tumor was scored and analyzed. Hepatic parenchymal enhancement on HAP was 12.07 + /-6.44 HU in group 1 and 16.03 + /-5.80 HU in group 2 (p .05). In the evaluation of conspicuity of hepatic artery, there was no statistically significant difference between the two groups (p > .05). The conspicuity of hypervascular tumors in group 2 was higher than in group 1 (p < .05). HAP spiral CT using a bolus triggering technique with a transition time of 11 seconds provides better HAP images than when the transition time is 7 seconds

Functional aspects of distal oesophageal spasm: the role of onset velocity and contraction amplitude on bolus transit

Science.gov (United States)

Pohl, Daniel; Ciolino, Jody; Roberts, Jason; Savarino, Edoardo; Freeman, Janice; Nietert, Paul J; Tutuian, Radu; Castell, Donald

2012-01-01

Background Distal oesophageal spasm (DES) is a rare and under-investigated motility abnormality. Recent studies indicate effective bolus transit in varying percentages of DES patients. Aim Explore functional aspects including contraction onset velocity and contraction amplitude cut-off values for simultaneous contractions to predict complete bolus transit Methods We re-examined data from 107 impedance-manometry recordings with a diagnosis of DES. Receiver operating characteristic (ROC) analysis was conducted, regarding effects of onset velocity on bolus transit taking into account distal oesophageal amplitude (DEA) and correcting for intra-individual repeated measures. Results Mean area under the ROC curve for saline and viscous swallows were 0.84±0.05 and 0.84±0.04, respectively. Velocity criteria of >30cm/s when DEA>100mmHg and 8cm/s when DEADEA>100mmHg and >7cm/s when DEAsensitivity of 75% and specificity of 80% to identify complete bolus transit. Using these criteria, final diagnosis changed in 44.9% of patients. Abnormal bolus transit was observed in 50.9% of newly diagnosed DES patients versus 7.5% of patients classified as normal. DES patients with DEA>100mmHg suffered twice as often from chest pain than those with DEA<100mmHg. Conclusion The proposed velocity cut-offs for diagnosing distal oesophageal spasm improve the ability to identify patients with spasm and abnormal bolus transit. PMID:22475443

Total intravenous anaesthesia by boluses or by continuous rate infusion of propofol in mute swans (Cygnus olor).

Science.gov (United States)

Müller, Kerstin; Holzapfel, Judith; Brunnberg, Leo

2011-07-01

To investigate intravenous (IV) propofol given by intermittent boluses or by continuous rate infusion (CRI) for anaesthesia in swans. Prospective randomized clinical study. Twenty mute swans (Cygnus olor) (eight immature and 12 adults) of unknown sex undergoing painless diagnostic or therapeutic procedures. Induction of anaesthesia was with 8 mg kg(-1) propofol IV. To maintain anaesthesia, ten birds (group BOLI) received propofol as boluses, whilst 10 (group CRI) received propofol as a CRI. Some physiological parameters were measured. Anaesthetic duration was 35 minutes. Groups were compared using Mann-Whitney U-test. Results are median (range). Anaesthetic induction was smooth and tracheal intubation was achieved easily in all birds. Bolus dose in group BOLI was 2.9 (1.3-4.3) mg kg(-1); interval between and number of boluses required were 4 (1-8) minutes and 6 (4-11) boluses respectively. Total dose of propofol was 19 (12.3-37.1) mg kg(-1). Awakening between boluses was very abrupt. In group CRI, propofol infusion rate was 0.85 (0.8-0.9) mg kg(-1) minute(-1), and anaesthesia was stable. Body temperature, heart and respiratory rates, oxygen saturation (by pulse oximeter) and reflexes did not differ between groups. Oxygen saturations (from pulse oximeter readings) were low in some birds. Following anaesthesia, all birds recovered within 40 minutes. In 55% of all, transient signs of central nervous system excitement occurred during recovery. 8 mg kg(-1) propofol appears an adequate induction dose for mute swans. For maintenance, a CRI of 0.85 mg kg(-1) minute(-1) produced stable anaesthesia suitable for painless clinical procedures. In contrast bolus administration, was unsatisfactory as birds awoke very suddenly, and the short intervals between bolus requirements hampered clinical procedures. Administration of additional oxygen throughout anaesthesia might reduce the incidence of low arterial haemoglobin saturation. © 2011 The Authors. Veterinary Anaesthesia and

Esophagogastric junction outflow obstruction is often associated with coexistent abnormal esophageal body motility and abnormal bolus transit.

Science.gov (United States)

Zheng, E; Gideon, R M; Sloan, J; Katz, P O

2017-10-01

Currently, the diagnosis of esophageal motility disorders is in part based upon a hierarchical algorithm in which abnormalities of the esophagogastric junction (EGJ) is prioritized. An important metric in evaluating the EGJ is the integrated relaxation pressure (IRP). Patients who do not have achalasia but are found to have an elevated IRP are diagnosed with EGJ outflow obstruction. It has been our observation that a subset of these patients also has a second named motility disorder and may also have abnormal bolus transit. The aim of this study is to determine the frequency of abnormal body motility and or abnormal bolus movement in patients with EGJ outflow obstruction. Further, in an effort to evaluate the potential clinical value in measuring bolus transit as a complement to esophageal manometry, specifically in patients with EGJ outflow obstruction, we analyzed the presenting symptoms of these patients. A total of 807 patients with a mean age of 53 years completed esophageal function testing with impedance monitoring and high-resolution manometry between January 2012 and October 2016. There were 74 patients with achalasia who were excluded from the study. Of the remaining 733 patients, 138 (19%) had an elevated IRP and were given a diagnosis of EGJ outflow obstruction. Among these patients, 56 (40%) were diagnosed with an abnormal motility pattern to liquids (ineffective esophageal motility = 28, distal esophageal spasm = 19, Jackhammer = 6), of which 44 (76%) had abnormal bolus transit to liquids, viscous, or both. In contrast, there were 82 patients with EGJ outflow obstruction and normal esophageal motility, of which 33 (40%) had abnormal bolus transit. Patients with preserved esophageal motility and EGJ outflow obstruction were then evaluated. Of the 733 patients, 299 (40%) had intact esophageal motility. Of the 299 patients with normal esophageal motility, 56 patients had an elevated IRP, of which 16 (28%) had abnormal bolus transit. There were 243 (33

Review article : intra-oesophageal impedance monitoring for the assessment of bolus transit and gastro-oesophageal reflux

NARCIS (Netherlands)

Conchillo, J. M.; Smout, A. J.

2009-01-01

Background Intra-oesophageal impedance monitoring can be used to assess the clearance of a swallowed bolus (oesophageal transit) and to detect gastro-oesophageal reflux independent of its acidity. Aim To discuss the clinical application of the impedance technique for the assessment of bolus transit

Transversus Abdominis Plane Catheter Bolus Analgesia after Major Abdominal Surgery

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Nils Bjerregaard

2012-01-01

Full Text Available Purpose. Transversus abdominis plane (TAP blocks have been shown to reduce pain and opioid requirements after abdominal surgery. The aim of the present case series was to demonstrate the use of TAP catheter injections of bupivacaine after major abdominal surgery. Methods. Fifteen patients scheduled for open colonic resection surgery were included. After induction of anesthesia, bilateral TAP catheters were placed, and all patients received a bolus dose of 20 mL bupivacaine 2.5 mg/mL with epinephrine 5 μg/mL through each catheter. Additional bolus doses were injected bilaterally 12, 24, and 36 hrs after the first injections. Supplemental pain treatment consisted of paracetamol, ibuprofen, and gabapentin. Intravenous morphine was used as rescue analgesic. Postoperative pain was rated on a numeric rating scale (NRS, 0–10 at regular predefined intervals after surgery, and consumption of intravenous morphine was recorded. Results. The TAP catheters were placed without any technical difficulties. NRS scores were ≤3 at rest and ≤5 during cough at 4, 8, 12, 18, 24, and 36 hrs after surgery. Cumulative consumption of intravenous morphine was 28 (23–48 mg (median, IQR within the first 48 postoperative hours. Conclusion. TAP catheter bolus injections can be used to prolong analgesia after major abdominal surgery.

Toxic leucoencephalopathy after 'chasing the dragon'.

Science.gov (United States)

Singh, Rajinder; Saini, Monica

2015-06-01

Toxic leucoencephalopathy (TLE) is a rare neurological complication of heroin abuse. 'Chasing the dragon' is an inhalational mode of heroin abuse that originated in Southeast Asia. Intriguingly, no cases of TLE have been reported from this region, although the inhalational mode of heroin abuse is common. We herein report the case of a middle-aged man with a history of polysubstance abuse who presented with progressive neurological symptoms and progressed to an uncommunicative state. While the initial impression was that of iatrogenic parkinsonism, diffuse leucoencephalopathy with sparing of the cerebellum was noted on magnetic resonance imaging. In view of his history of inhalational heroin abuse close to the onset of the neurological symptoms, a diagnosis of TLE was made. No clinical improvement was noted with administration of a dopaminergic agent. This is the first known case of delayed TLE following heroin inhalation from Southeast Asia with the unusual feature of cerebellar sparing.

Significance chasing in research practice: causes, consequences and possible solutions.

Science.gov (United States)

Ware, Jennifer J; Munafò, Marcus R

2015-01-01

The low reproducibility of findings within the scientific literature is a growing concern. This may be due to many findings being false positives which, in turn, can misdirect research effort and waste money. We review factors that may contribute to poor study reproducibility and an excess of 'significant' findings within the published literature. Specifically, we consider the influence of current incentive structures and the impact of these on research practices. The prevalence of false positives within the literature may be attributable to a number of questionable research practices, ranging from the relatively innocent and minor (e.g. unplanned post-hoc tests) to the calculated and serious (e.g. fabrication of data). These practices may be driven by current incentive structures (e.g. pressure to publish), alongside the preferential emphasis placed by journals on novelty over veracity. There are a number of potential solutions to poor reproducibility, such as new publishing formats that emphasize the research question and study design, rather than the results obtained. This has the potential to minimize significance chasing and non-publication of null findings. Significance chasing, questionable research practices and poor study reproducibility are the unfortunate consequence of a 'publish or perish' culture and a preference among journals for novel findings. It is likely that top-down change implemented by those with the ability to modify current incentive structure (e.g. funders and journals) will be required to address problems of poor reproducibility. © 2014 Society for the Study of Addiction.

Dextrose boluses versus burette dextrose infusions in prevention of ...

African Journals Online (AJOL)

The incidence of hypoglycemia in the bolus arm was 59% (40/68) compared to 11% (8/72) in the ... and safety monitoring board (DSMB) was set up to oversee to ..... On the other hand, Namukwaya et al in a prospective study at Mulago ...

Impacts of palatal coverage on bolus formation during mastication and swallowing and subsequent adaptive changes.

Science.gov (United States)

Sato, T; Furuya, J; Tamada, Y; Kondo, H

2013-10-01

Palatal coverage is often required for elderly edentulous patients with complete dentures. The purpose of this study was to clarify impacts of palatal coverage on bolus formation and subsequent adaptive changes. Subjects were 18 healthy young dentulous adults who wore 1·5-mm-thick palatal plates. Subjects were asked to feed 12 g of bicoloured rice as usual, and the bolus formation by mastication and swallowing in the pharynx was observed using a nasal videoendoscopy. The bolus formation index (BFI), number of mastication strokes until swallowing, visual analogue scale about swallowing easiness and masticatory performance using colour-changeable gum were measured under three conditions: before placement of the palatal plate (day 0), immediately after placement (day 1) and after 7 days of wearing the plate (day 7). BFI and visual analogue scale on day 1 were significantly lower than those on day 0, but those on day 7 significantly recovered to the level of day 0. The number of mastication strokes did not change from day 0 to day 1, however, that on day 7 was significantly higher. Masticatory performance on days 1 and 7 was significantly lower than that on day 0. Although palatal coverage inhibits bolus formation during feeding, subjects increased the number of mastication strokes until swallowing threshold as they adapted to palatal coverage over time. This adaptive change was due to compensate for the lowered masticatory performance to achieve bolus formation for comfortable swallowing. © 2013 John Wiley & Sons Ltd.

Fox Chase Cancer Center's Genitourinary Division: a national resource for research, innovation and patient care.

Science.gov (United States)

Uzzo, Robert G; Horwitz, Eric M; Plimack, Elizabeth R

2016-04-01

Founded in 1904, Fox Chase Cancer Center remains committed to its mission. It is one of 41 centers in the country designated as a Comprehensive Cancer Center by the National Cancer Institute, is a founding member of the National Comprehensive Cancer Network, holds the magnet designation for nursing excellence, is one of the first to establish a family cancer risk assessment program, and has achieved national distinction because of the scientific discoveries made there that have advanced clinical care. Two of its researchers have won Nobel prizes. The Genitourinary Division is nationally recognized and viewed as one of the top driving forces behind the growth of Fox Chase due to its commitment to initiating and participating in clinical trials, its prolific contributions to peer-reviewed publications and presentations at scientific meetings, its innovations in therapies and treatment strategies, and its commitment to bringing cutting-edge therapies to patients.

Magnetic Resonance Imaging of Heart Failure Using a Swine Model

Science.gov (United States)

2011-03-21

Suppl):I437-442. 36. McAlister FA, Teo KK, Taher M, Montague TJ, Humen D, Cheung L, Kiaii M, Yim R, Armstrong PW. Insights into the contemporary...Imaging 2001;13:714-721. 8. Ho VB, Meaney JF, Kent KC , Choyke PL, Watts R, Hood MN, Wang Y, Winchester P, Dong Q, Prince MR. Bolus-chase peripheral MR

SU-F-T-442: Dose Distribution Comparison for Post-Laryngectomy Stoma Area Between Conventional AP and VMAT Plans with Or Without Bolus

Energy Technology Data Exchange (ETDEWEB)

Lee, B [University of California, Los Angeles, Los Angeles, CA (United States); Zhang, J; Cho-Lim, J [VA Long Beach Healthcare System, Long Beach, CA (United States); University of California, Irvine, Orange, CA (United States); Leu, M [VA Greater Los Angeles Healthcare System, Los Angeles, CA (United States); Inouye, W [VA Long Beach Healthcare System, Long Beach, CA (United States); Lorentz, W [University of California, Los Angeles, Los Angeles, CA (United States); VA Greater Los Angeles Healthcare System, Los Angeles, CA (United States); Lee, S [University of California, Los Angeles, Los Angeles, CA (United States); VA Long Beach Healthcare System, Long Beach, CA (United States); VA Greater Los Angeles Healthcare System, Los Angeles, CA (United States)

2016-06-15

Purpose: To compare dose distributions of conventional AP vs. VMAT treatment plans with or without bolus around post-laryngectomy stoma. Methods: Radiation dose coverage for post-laryngectomy stoma was analyzed using a set of real-case CT-simulation images. After meticulous contouring of the catheter cuff, stoma lumen, peri-stoma skin and subclinical tumor bed at the larynx, the resulting dosimetry plans were analyzed with or without a 5 mm bolus placement. Wet gauze was used to minimize the effect of any air gap. Four plans were generated: AP superclavicular (SCV) plan with or without bolus, and VMAT plan with or without bolus. A dose of 60Gy in 30 fractions was prescribed at 3 cm depth for AP SCV plan, and to 95% of the PTV volume for VMAT plan. Results: For the conventional AP SCV plan, the peri-stoma skin dose is sensitive to bolus placement as well as air gap compensation by wetted gauze (V95% of 20.7%, 33.0% and 94.8% for no bolus, bolus without and with air gap compensation, respectively). For stoma lumen, the dose drops off rapidly in depth. The catheter cuff may have certain dose-buildup effect, but air gap around it and under the bolus placed can pose a more serious problem. The dose distributions of the two VMAT plans are moderately different for peri-stoma skin (V95% of 95.0% with bolus and air gap compensation, and 82.3% without bolus), but nearly identical for stoma lumen (V95% of 91.5% and 92.0%, respectively). VMAT allows beamlets with different angles of incidence that helped achieve such dose distribution around the stoma even without bolus placement. Conclusion: Overall, the dose coverage around the stoma in the VMAT plan is better than the conventional AP SCV plan. To achieve optimal dose distribution, it is still recommended to place physical bolus and reduce the air gaps.

MR liver imaging after bolus administration of Teslascan

International Nuclear Information System (INIS)

Costa, S.; Marti-Bonmati, L.; Delgado, F.; Torregrosa, A.

2003-01-01

Mn-DPDP (Teslascan. Amersham-Health) improves the detection of small hepatic lesions and the accuracy with which certain focal lesions can be characterized. Slow infusion (2-3 ml per minute) is the accepted European standard for its administration. Our aim was to evaluate the efficiency of bolus administration. A prospective MR evaluation at 0.5 was performed on 31 consecutive patients. A GE T1 sequence was performed on all before contrast administration. Teslascan was administered by rapid intravenous infusion (=1 ml/s), and the GE sequence was repeated and completed by an STIR sequence. Correlations between presence of cirrhosis and enhancement pattern of hepatic parenchyma, number of lesions detected before and after bolus administration, as well as lesion histology and degree of enhancement were all analyzed. Adverse clinical reactions as reported by patients were also noted. Cirrhotic liver was found in 49% of the patients. Enhancement was mainly heterogeneous with hypointense areas and heterogeneous with hypointense areas together with more greatly enhanced regenerative nodules. Enhancement of cirrhotic livers was homogeneous in a third of the cases. Non-cirrhotic patients exhibited a homogeneous hepatic mass in most cases,ith only one liver showing heterogeneous enhancement containing hypointense bands caused by necrotic debris having resulted from treated metastases. Enhancement pattern differences between cirrhotic and non-cirrhotic patients were statistically significant (p=0.001). In 20 of the 31 patients, solid focal lesions were detected. Sequences performed after bolus administration of contrast media detected more lesions than did those before administration. Combination of both post-administration sequences (T1 and STIR) detected the most lesions, with differences between it and pre-administration sequences being statistically significant (p=0.0014). There was observed a varying degree of lesion enhancement. Such variability was associated with the

Causes of death after fluid bolus resuscitation: new insights from FEAST.

Science.gov (United States)

Myburgh, John; Finfer, Simon

2013-03-14

The Fluid Expansion as Supportive Therapy (FEAST study) was an extremely well conducted study that gave unexpected results. The investigators had reported that febrile children with impaired perfusion treated in low-income countries without access to intensive care are more likely to die if they receive bolus resuscitation with albumin or saline compared with no bolus resuscitation at all. In a secondary analysis of the trial, published in BMC Medicine, the authors found that increased mortality was evident in patients who presented with clinical features of severe shock in isolation or in conjunction with features of respiratory or neurological failure. The cause of excess deaths was primarily refractory shock and not fluid overload. These features are consistent with a potential cardiotoxic or ischemia-reperfusion injury following resuscitation with boluses of intravenous fluid. Although these effects may have been amplified by the absence of invasive monitoring, mechanical ventilation or vasopressors, the results provide compelling insights into the effects of intravenous fluid resuscitation and potential adverse effects that extend beyond the initial resuscitation period. These data add to the increasing body of literature about the safety and efficacy of intravenous resuscitation fluids, which may be applicable to management of other populations of critically ill patients.

Broadening Participation Not Border Protection: How Universities Can Support Women in Computer Science

Science.gov (United States)

Michell, Dee; Szorenyi, Anna; Falkner, Katrina; Szabo, Claudia

2017-01-01

Computer science, like technology in general, is seen as a masculine field and the under-representation of women an intransigent problem. In this paper, we argue that the cultural belief in Australia that computer science is a domain for men results in many girls and women being chased away from that field as part of a border protection campaign…

A prospective, randomized, blinded-endpoint, controlled study - continuous epidural infusion versus programmed intermittent epidural bolus in labor analgesia

Directory of Open Access Journals (Sweden)

Joana Nunes

Full Text Available Abstract Background: There is evidence that administration of a programmed intermittent epidural bolus (PIEB compared to continuous epidural infusion (CEI leads to greater analgesia efficacy and maternal satisfaction with decreased anesthetic interventions. Methods: In this study, 166 women with viable pregnancies were included. After an epidural loading dose of 10 mL with Ropivacaine 0.16% plus Sufentanil 10 µg, parturient were randomly assigned to one of three regimens: A - Ropivacaine 0.15% plus Sufentanil 0.2 µg/mL solution as continuous epidural infusion (5 mL/h, beginning immediately after the initial bolus; B - Ropivacaine 0.1% plus Sufentanil 0.2 µg/mL as programmed intermittent epidural bolus and C - Same solution as group A as programmed intermittent epidural bolus. PIEB regimens were programmed as 10 mL/h starting 60 min after the initial bolus. Rescue boluses of 5 mL of the same solution were administered, with the infusion pump. We evaluated maternal satisfaction using a verbal numeric scale from 0 to 10. We also evaluated adverse, maternal and neonatal outcomes. Results: We analyzed 130 pregnants (A = 60; B = 33; C = 37. The median verbal numeric scale for maternal satisfaction was 8.8 in group A; 8.6 in group B and 8.6 in group C (p = 0.83. We found a higher caesarean delivery rate in group A (56.7%; p = 0.02. No differences in motor block, instrumental delivery rate and neonatal outcomes were observed. Conclusions: Maintenance of epidural analgesia with programmed intermittent epidural bolus is associated with a reduced incidence of caesarean delivery with equally high maternal satisfaction and no adverse outcomes.

Evaluation of surface and shallow depth dose reductions using a Superflab bolus during conventional and advanced external beam radiotherapy.

Science.gov (United States)

Yoon, Jihyung; Xie, Yibo; Zhang, Rui

2018-03-01

The purpose of this study was to evaluate a methodology to reduce scatter and leakage radiations to patients' surface and shallow depths during conventional and advanced external beam radiotherapy. Superflab boluses of different thicknesses were placed on top of a stack of solid water phantoms, and the bolus effect on surface and shallow depth doses for both open and intensity-modulated radiotherapy (IMRT) beams was evaluated using thermoluminescent dosimeters and ion chamber measurements. Contralateral breast dose reduction caused by the bolus was evaluated by delivering clinical postmastectomy radiotherapy (PMRT) plans to an anthropomorphic phantom. For the solid water phantom measurements, surface dose reduction caused by the Superflab bolus was achieved only in out-of-field area and on the incident side of the beam, and the dose reduction increased with bolus thickness. The dose reduction caused by the bolus was more significant at closer distances from the beam. Most of the dose reductions occurred in the first 2-cm depth and stopped at 4-cm depth. For clinical PMRT treatment plans, surface dose reductions using a 1-cm Superflab bolus were up to 31% and 62% for volumetric-modulated arc therapy and 4-field IMRT, respectively, but there was no dose reduction for Tomotherapy. A Superflab bolus can be used to reduce surface and shallow depth doses during external beam radiotherapy when it is placed out of the beam and on the incident side of the beam. Although we only validated this dose reduction strategy for PMRT treatments, it is applicable to any external beam radiotherapy and can potentially reduce patients' risk of developing radiation-induced side effects. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

SU-F-T-325: On the Use of Bolus in Dosimetry and Dose Reduction for Pacemaker and Defibrillator

International Nuclear Information System (INIS)

Liu, W; Kenneth, R; Higgins, S; Nath, R; Zhu, D; Trumpore, S; Chen, Z

2016-01-01

Purpose: Special attention is required in planning and administering radiation therapy to patients with cardiac implantable electronic devices (CIEDs), such as pacemaker and defibrillator. The range of dose to CIEDs that can induce malfunction is very large among CIEDs. Significant defects have been reported at dose as low as 0.15Gy. Failures causing discomfort have been reported at dose as low as 0.05Gy. Therefore, accurate estimation of dose to CIED and dose reduction are both important even if the dose is expected to be less than the often-used 2Gy limit. We investigate the use of bolus in in vivo dosimetry for CIEDs. Methods: In our clinic, high-energy beams (>10MV) are not used for patients with CIED due to neutron production. Solid water phantom measurements of out-of-field dose for a 6MV beam were performed using parallel plate chamber at different depth with and without 2cm bolus covering the chamber. In vivo dosimetry at skin surface above the pacemaker was performed with and without bolus for 3 patients with pacemaker <5cm from the field edge. Results: Chamber measured dose at depth ∼1 to 1.5cm below the skin surface, where the CIED is normally located, was reduced by ∼6% – 20% with bolus. The dose reduction became smaller at deeper depth. In vivo dosimetry at skin surface also yielded ∼20% – 60% lower dose when using bolus for the 3 patients. In general, TPS calculation underestimated the dose. The dose measured with bolus is closer to the dose at the depth of the pacemaker and less affected by contaminant electrons and linac head leakage. Conclusion: In vivo CIED dose measurements should be performed with 1 to 2cm bolus covering the dosimeter on the skin above the CIED for more accurate CIED dose estimation. The use of bolus also reduces the dose delivered to CIED.

SU-F-T-325: On the Use of Bolus in Dosimetry and Dose Reduction for Pacemaker and Defibrillator

Energy Technology Data Exchange (ETDEWEB)

Liu, W; Kenneth, R; Higgins, S; Nath, R [Yale University School of Medicine, New Haven, CT (United States); Zhu, D [Saint Thomas Hospital, Murfreesboro, TN (United States); Trumpore, S [Yale-New Haven Hospital, New Haven, CT (United States); Chen, Z [Yale New Haven Hospital, New Haven, CT (United States)

2016-06-15

Purpose: Special attention is required in planning and administering radiation therapy to patients with cardiac implantable electronic devices (CIEDs), such as pacemaker and defibrillator. The range of dose to CIEDs that can induce malfunction is very large among CIEDs. Significant defects have been reported at dose as low as 0.15Gy. Failures causing discomfort have been reported at dose as low as 0.05Gy. Therefore, accurate estimation of dose to CIED and dose reduction are both important even if the dose is expected to be less than the often-used 2Gy limit. We investigate the use of bolus in in vivo dosimetry for CIEDs. Methods: In our clinic, high-energy beams (>10MV) are not used for patients with CIED due to neutron production. Solid water phantom measurements of out-of-field dose for a 6MV beam were performed using parallel plate chamber at different depth with and without 2cm bolus covering the chamber. In vivo dosimetry at skin surface above the pacemaker was performed with and without bolus for 3 patients with pacemaker <5cm from the field edge. Results: Chamber measured dose at depth ∼1 to 1.5cm below the skin surface, where the CIED is normally located, was reduced by ∼6% – 20% with bolus. The dose reduction became smaller at deeper depth. In vivo dosimetry at skin surface also yielded ∼20% – 60% lower dose when using bolus for the 3 patients. In general, TPS calculation underestimated the dose. The dose measured with bolus is closer to the dose at the depth of the pacemaker and less affected by contaminant electrons and linac head leakage. Conclusion: In vivo CIED dose measurements should be performed with 1 to 2cm bolus covering the dosimeter on the skin above the CIED for more accurate CIED dose estimation. The use of bolus also reduces the dose delivered to CIED.

Radionuclide esophageal transit of a liquid bolus: A reappraisal

International Nuclear Information System (INIS)

Holloway, R.H.; Lange, R.C.; Magyar, L.; Greene, R.; McCallum, R.W.

1984-01-01

Measurement of radionuclide esophageal transit (RT) using a liquid bolus has been suggested as a screening test for esophageal motor disorders (EMD). The authors prospectively evaluated RT in 49 patients referred for esophageal manometry. Ten subjects with normal manometry served as controls. RT was performed using two 10 ml boluses of water labeled with 250 μCi /sup 99m/Tc-sulfur colloid. Patients were studied supine and the swallow sequences framed in 1 second intervals. Transit time was measured from the time of entry to the time of exit from the esophagus. Mean transit time in normal subjects was 9.1 +- 2.1 (SD) sec. The test was abnormal if the transit time was prolonged (> 15 sec) in at least 1 of 2 swallows. RT agreed with manometry in 36/49 patients (75%), including 9/9 achalasics, 3/3 diffuse esophageal spasm, 3/7 'nutcracker esophagus' and 7/8 non-specific motor disorders (NSMD). 4/18 patients with normal manometry had abnormal RT. 9/31 patients with abnormal manometry had normal RT, including 4/7 nutcracker esophagus, 3/3 hypertrensive LES, 1/1 scleroderma and 1/8 NSMD. Sensitivity of RT was 70% and specificity 77%. The false positive rate was 15% and the false negative rate 39%. The authors conclude the following: 1) RT identifies patients with absent or impaired peristalsis; 2) There is substantial incidence of false negatives among patients with manometric disorders but normal peristalsis; and 3) Abnormal RT did occur in some patients with normal menometry. RT using a liquid bolus may not be sensitive enough as a screening test for EMD, but it may be an important adjunct to manometry

Perception of Diabetic Patients Regarding Basal Bolus Insulin Injections and Outcome of its Use

International Nuclear Information System (INIS)

Shahid, M.; Sarfraz, A.; Mahar, S. A.; Alam, M.; Shaikh, S.; Shahid, N.

2016-01-01

Objective: To assess the perceptions regarding basal bolus insulin injections and the changes in blood glucose levels and glycosylated hemoglobin (HbA1c) before and after 3 months of such treatment in diabetic patients. Study Design: Quasi-experimental study. Place and Duration of Study: Department of Endocrinology, Liaquat National Hospital, Karachi, from December 2014 to March 2015. Methodology: A total of 222 diabetic patients started on basal bolus insulin injection were enrolled and asked to answer 17 questions. Those with complications of diabetes were excluded. Fasting blood glucose (FBS), random blood glucose (RBS) and HbA1c levels were checked initially, and after 3 months of getting basal bolus insulin. Paired t-test and chi-square test were used for determining p-value with significance at p < 0.05. Results: Majority (n=217, 97.7 percentage) of the patients were previously taking other insulins. Before starting this treatment, the mean FBS was 260.5 ± 52.2 mg/dl, RBS was 385.5 percentage 47.61 mg/dl and HbA1c was 12.76 percentage 1.92 percentage. After 3 months of treatment, FBS improved to 117.9 ± 14.2 mg/dl, RBS was 156.7 ± 17.09 mg/dl and HbA1c was 7.72 ± 4.41 percentage (p < 0.001). Two hundred and sixteen (97.3 percentage) patients believed that basal bolus insulin was started as their diabetes worsened; 15 (70.70 percentage) thought that their blood glucose control would improve with the use of this form of insulin. One hundred and ninety four (87.4 percentage) had fear of needle injections. Perceptions regarding hypoglycemia with this form of insulin were observed in 157 (70.7 percentage). One hundred and twenty seven (84.1 percentage) of the females and 51 (71.8 percentage) of the males thought that the basal bolus insulin regimen was too expensive (p=0.032). Conclusion: There were many misconceptions in patients who were started on basal bolus insulin. Marked improvement in blood glucose levels and HbA1c were observed after the use of this

Ocular Dynamics of Bolus Ingestion of Eleis guineensis Sap (Palm ...

African Journals Online (AJOL)

Elaeis guineensis), and is widely consumed among the various ethnic nationalities in Nigeria. The effect of bolus ingestion of 600ml, palm wine was undertaken so as to determine its ocular dynamics in healthy volunteers. Results showed that ...

Comparison of first-pass and second-bolus dynamic susceptibility perfusion MRI in brain tumors

International Nuclear Information System (INIS)

Spampinato, M.V.; Besenski, Nada; Rumboldt, Zoran; Wooten, Caroline; Dorlon, Margaret

2006-01-01

Our goal was to evaluate whether the T1 shortening effect caused by contrast leakage into brain tumors, a well-known confounding effect in the quantification of relative cerebral blood volume (rCBV) measurements, may be corrected by the administration of a predose of gadolinium-DTPA. As part of their presurgical imaging protocol, 25 patients with primary brain tumors underwent two consecutive dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion MR studies. Intratumoral rCBV measurements and normalized rCBV values obtained during the first-pass and second-bolus studies were compared (Wilcoxon signed-ranks test). The frequency of relatively increased rCBV ratios on the second-bolus study was compared between enhancing and non-enhancing neoplasms (Fisher's exact test). Postprocessing perfusion studies were evaluated for image quality on a scale of 0-3 (Wilcoxon signed-ranks test). Four studies were excluded due to unacceptable image quality. Mean normalized rCBVs were 9.04 (SD 4.64) for the first-pass and 7.99 (SD 3.84) for the second-bolus study. There was no statistically significant difference between the two perfusion studies in either intratumoral rCBV (P=0.237) or rCBV ratio (P=0.181). Five enhancing and four non-enhancing tumors showed a relative increase in rCBV ratio on the second-bolus study, without a significant difference between the groups. Image quality was not significantly different between perfusion studies. Our results did not demonstrate a significant difference between first-pass and second-bolus rCBV measurements in DSC perfusion MR imaging. The administration of a predose of gadolinium-DTPA does not appear to be an efficient way of compensating for the underestimation of intratumoral rCBV values due to the T1 shortening effect. (orig.)

Review of adverse reactions, including anaphylaxis, in 4,260 intravenous bolus injections

International Nuclear Information System (INIS)

Kanal, E.; Applegate, G.R.; Gillen, C.P.

1990-01-01

This paper evaluates the incidence and type of adverse reactions to Gd-DTPA (Magnevist) after bolus administration in an active clinical MR setting. Between May 1988 and March 1990, 4,260 bolus intravenous injections of Gd-DTPA, 0.1 mmol/kg, were administered during clinical MR examinations. Patient tolerance and reactions were recorded in each instance. All cases of suspected local infiltration were excluded from this study. Review of this data revealed 15 instances of nausea and 12 of emesis following contrast administration. In addition, there were five or fewer cases of associated headaches, dizziness, odd tastes, seizures (with prior seizure histories) mild chest pain, palpitations, hives, or wheezing

Impaired bolus transit across the esophagogastric junction in postfundoplication dysphagia

NARCIS (Netherlands)

Scheffer, R. C. H.; Samsom, M.; Haverkamp, A.; Oors, J.; Hebbard, G. S.; Gooszen, H. G.

2005-01-01

This study assessed the effect of fundoplication on liquid and solid bolus transit across the esophagogastric junction (EGJ) in relation to EGJ dynamics and dysphagia. Twelve patients with gastro-esophageal reflux disease (GERD) were studied before and after fundoplication. Concurrent

The Impact of Injector-Based Contrast Agent Administration on Bolus Shape and Magnetic Resonance Angiography Image Quality.

Science.gov (United States)

Jost, Gregor; Endrikat, Jan; Pietsch, Hubertus

2017-01-01

To compare injector-based contrast agent (CA) administration with hand injection in magnetic resonance angiography (MRA). Gadobutrol was administered in 6 minipigs with 3 protocols: (a) hand injection (one senior technician), (b) hand injection (6 less-experienced technicians), and (c) power injector administration. The arterial bolus shape was quantified by test bolus measurements. A head and neck MRA was performed for quantitative and qualitative comparison of signal enhancement. A significantly shorter time to peak was observed for protocol C, whereas no significant differences between protocols were found for peak height and bolus width. However, for protocol C, these parameters showed a much lower variation. The MRA revealed a significantly higher signal-to-noise ratio for injector-based administration. A superimposed strong contrast of the jugular vein was found in 50% of the hand injections. Injector-based CA administration results in a more standardized bolus shape, a higher vascular contrast, and a more robust visualization of target vessels.

The Impact of Injector-Based Contrast Agent Administration on Bolus Shape and Magnetic Resonance Angiography Image Quality

Directory of Open Access Journals (Sweden)

Gregor Jost

2017-04-01

Full Text Available Objective: To compare injector-based contrast agent (CA administration with hand injection in magnetic resonance angiography (MRA. Methods: Gadobutrol was administered in 6 minipigs with 3 protocols: (a hand injection (one senior technician, (b hand injection (6 less-experienced technicians, and (c power injector administration. The arterial bolus shape was quantified by test bolus measurements. A head and neck MRA was performed for quantitative and qualitative comparison of signal enhancement. Results: A significantly shorter time to peak was observed for protocol C, whereas no significant differences between protocols were found for peak height and bolus width. However, for protocol C, these parameters showed a much lower variation. The MRA revealed a significantly higher signal-to-noise ratio for injector-based administration. A superimposed strong contrast of the jugular vein was found in 50% of the hand injections. Conclusions: Injector-based CA administration results in a more standardized bolus shape, a higher vascular contrast, and a more robust visualization of target vessels.

A prospective, randomized, blinded-endpoint, controlled study - continuous epidural infusion versus programmed intermittent epidural bolus in labor analgesia.

Science.gov (United States)

Nunes, Joana; Nunes, Sara; Veiga, Mariano; Cortez, Mara; Seifert, Isabel

2016-01-01

There is evidence that administration of a programmed intermittent epidural bolus (PIEB) compared to continuous epidural infusion (CEI) leads to greater analgesia efficacy and maternal satisfaction with decreased anesthetic interventions. In this study, 166 women with viable pregnancies were included. After an epidural loading dose of 10mL with Ropivacaine 0.16% plus Sufentanil 10μg, parturient were randomly assigned to one of three regimens: A - Ropivacaine 0.15% plus Sufentanil 0.2μg/mL solution as continuous epidural infusion (5mL/h, beginning immediately after the initial bolus); B - Ropivacaine 0.1% plus Sufentanil 0.2μg/mL as programmed intermittent epidural bolus and C - Same solution as group A as programmed intermittent epidural bolus. PIEB regimens were programmed as 10mL/h starting 60min after the initial bolus. Rescue boluses of 5mL of the same solution were administered, with the infusion pump. We evaluated maternal satisfaction using a verbal numeric scale from 0 to 10. We also evaluated adverse, maternal and neonatal outcomes. We analyzed 130 pregnants (A=60; B=33; C=37). The median verbal numeric scale for maternal satisfaction was 8.8 in group A; 8.6 in group B and 8.6 in group C (p=0.83). We found a higher caesarean delivery rate in group A (56.7%; p=0.02). No differences in motor block, instrumental delivery rate and neonatal outcomes were observed. Maintenance of epidural analgesia with programmed intermittent epidural bolus is associated with a reduced incidence of caesarean delivery with equally high maternal satisfaction and no adverse outcomes. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

Chase and NYANA: A Partnership To Remove Barriers to Job Performance 1993-94. Final Report.

Science.gov (United States)

Auerbach, Charles

A workplace literacy program implemented cooperatively by the New York Association for New Americans, Inc. (NYANA) and Chase Manhattan Bank is reported. The federally-funded project provided individualized communication workplace behavior and skills training in English as a Second Language for 30 limited-English-proficient bank employees working…

A prospective, randomized, blinded-endpoint, controlled study – continuous epidural infusion versus programmed intermittent epidural bolus in labor analgesia

Directory of Open Access Journals (Sweden)

Joana Nunes

2016-09-01

Full Text Available Background: There is evidence that administration of a programmed intermittent epidural bolus (PIEB compared to continuous epidural infusion (CEI leads to greater analgesia efficacy and maternal satisfaction with decreased anesthetic interventions. Methods: In this study, 166 women with viable pregnancies were included. After an epidural loading dose of 10 mL with Ropivacaine 0.16% plus Sufentanil 10 μg, parturient were randomly assigned to one of three regimens: A – Ropivacaine 0.15% plus Sufentanil 0.2 μg/mL solution as continuous epidural infusion (5 mL/h, beginning immediately after the initial bolus; B – Ropivacaine 0.1% plus Sufentanil 0.2 μg/mL as programmed intermittent epidural bolus and C – Same solution as group A as programmed intermittent epidural bolus. PIEB regimens were programmed as 10 mL/h starting 60 min after the initial bolus. Rescue boluses of 5 mL of the same solution were administered, with the infusion pump. We evaluated maternal satisfaction using a verbal numeric scale from 0 to 10. We also evaluated adverse, maternal and neonatal outcomes. Results: We analyzed 130 pregnants (A = 60; B = 33; C = 37. The median verbal numeric scale for maternal satisfaction was 8.8 in group A; 8.6 in group B and 8.6 in group C (p = 0.83. We found a higher caesarean delivery rate in group A (56.7%; p = 0.02. No differences in motor block, instrumental delivery rate and neonatal outcomes were observed. Conclusions: Maintenance of epidural analgesia with programmed intermittent epidural bolus is associated with a reduced incidence of caesarean delivery with equally high maternal satisfaction and no adverse outcomes. Resumo: Justificativa: Há evidências de que a administração de um bolus epidural intermitente programado (BEIP comparada à infusão epidural contínua (IEC resulta em maior eficácia da analgesia e da satisfação materna, com redução das intervenções anestésicas. Métodos: Neste estudo, 166

Study of dose modification in skin cancers induced by the kind of bolus used - Bibliography

International Nuclear Information System (INIS)

Camilleri, Jeremy

2011-01-01

As tumour irradiation modalities differ from one pathology to another, and are even proper to each pathology (they depend on tumour nature, histology, size, location, and so on), but as therapeutic objectives remain unchanged (to deliver the prescribed dose to the target-volume with the highest possible precision while preserving as much as possible sane tissues as well as neighbouring organs at risk), this bibliographical study aims, on the one hand, at quantifying the dose variation generated by heterogeneous structures crossed by the electron beam, and on the other hand, at optimising the use of boluses during surface irradiations, notably in the case of skin cancers. The author addresses therapeutic indications of irradiation of skin cancers and of thoracic wall for which the application of a bolus is required, and then the associated irradiation techniques as well as bolus characteristics

Onset and effectiveness of rocuronium for rapid onset of paralysis in patients with major burns: priming or large bolus

Science.gov (United States)

Han, T.-H.; Martyn, J. A. J.

2009-01-01

Background Burn injury leads to resistance to the effects of non-depolarizing muscle relaxants. We tested the hypothesis that a larger bolus dose is as effective as priming for rapid onset of paralysis after burns. Methods Ninety adults, aged 18–59 yr with 40 (2)% [mean (se)] burn and 30 (2) days after injury, received rocuronium as a priming dose followed by bolus (0.06+0.94 mg kg−1), or single bolus of either 1.0 or 1.5 mg kg−1. Sixty-one non-burned, receiving 1.0 mg kg−1 as a primed (0.06+0.94 mg kg−1) or full bolus dose, served as controls. Acceleromyography measured the onset times. Results Priming when compared with 1.0 mg kg−1 bolus in burned patients shortened the time to first appearance of twitch depression (30 vs 45 s, P<0.05) and time to maximum twitch inhibition (135 vs 210 s, P<0.05). The onset times between priming and higher bolus dose (1.5 mg kg−1) were not different (30 vs 30 s for first twitch depression and 135 vs 135 s for maximal depression, respectively). The onset times in controls, however, were significantly (P<0.05) faster than burns both for priming and for full bolus (15 and 15 s, respectively, for first twitch depression and 75 and 75 s for maximal depression). Priming caused respiratory distress in 10% of patients in both groups. Intubating conditions in burns were significantly better with 1.5 mg kg−1 than with priming or full 1.0 mg kg−1 bolus. Conclusions A dose of 1.5 mg kg−1 not only produces an initial onset of paralysis as early as 30 s, which we speculate could be a reasonable onset time for relief of laryngospasm, but also has an onset as fast as priming with superior intubating conditions and no respiratory side-effects. PMID:19029093

Use of cornmeal bolus as an aid in obtaining cranial four-vessel angiograms.

Science.gov (United States)

Weathers, R M; Lee, A

1975-01-01

In cranial angiography it has always been difficult to visualize extracranial vessels of the cervico-thoracic region, upon one radiograph, by using the same exposure factors for both regions. For this reason, we experimented and found that by applying a dry cornmeal bolus on specific areas of the neck a technically superior radiograph of these regions can be achieved. This bolus simulated added soft tissue to the cervical region. The density of the cervical region is now similar to that of the upper thoracic. As a result, factors set for one exposure will adequately penetrate both areas.

Evaluation of the Eclipse eMC algorithm for bolus electron conformal therapy using a standard verification dataset.

Science.gov (United States)

Carver, Robert L; Sprunger, Conrad P; Hogstrom, Kenneth R; Popple, Richard A; Antolak, John A

2016-05-08

The purpose of this study was to evaluate the accuracy and calculation speed of electron dose distributions calculated by the Eclipse electron Monte Carlo (eMC) algorithm for use with bolus electron conformal therapy (ECT). The recent com-mercial availability of bolus ECT technology requires further validation of the eMC dose calculation algorithm. eMC-calculated electron dose distributions for bolus ECT have been compared to previously measured TLD-dose points throughout patient-based cylindrical phantoms (retromolar trigone and nose), whose axial cross sections were based on the mid-PTV (planning treatment volume) CT anatomy. The phantoms consisted of SR4 muscle substitute, SR4 bone substitute, and air. The treatment plans were imported into the Eclipse treatment planning system, and electron dose distributions calculated using 1% and processors (Intel Xeon E5-2690, 2.9 GHz) on a framework agent server (FAS). In comparison, the eMC was significantly more accurate than the pencil beam algorithm (PBA). The eMC has comparable accuracy to the pencil beam redefinition algorithm (PBRA) used for bolus ECT planning and has acceptably low dose calculation times. The eMC accuracy decreased when smoothing was used in high-gradient dose regions. The eMC accuracy was consistent with that previously reported for accuracy of the eMC electron dose algorithm and shows that the algorithm is suitable for clinical implementation of bolus ECT.

Serum levels of bupivacaine after pre-peritoneal bolus vs. epidural bolus injection for analgesia in abdominal surgery: A safety study within a randomized controlled trial

NARCIS (Netherlands)

Mungroop, Timothy H.; van Samkar, Ganapathy; Geerts, Bart F.; van Dieren, Susan; Besselink, Marc G.; Veelo, Denise P.; Lirk, Philipp

2017-01-01

Continuous wound infiltration (CWI) has become increasingly popular in recent years as an alternative to epidural analgesia. As catheters are not placed until the end of surgery, more intraoperative opioid analgesics might be needed. We, therefore, added a single pre-peritoneal bolus of bupivacaine

Post-mastectomy radiation therapy without usage of a bolus may be a reasonable option

International Nuclear Information System (INIS)

Nakamura, Naoki; Arahira, Satoko; Zenda, Sadamoto; Yoneyama, Kimiyasu; Mukai, Hirofumi; Onozawa, Masakatsu; Toshima, Masamichi; Motegi, Atsushi; Hirano, Yasuhiro; Hojo, Hidehiro; Kibe, Yuichi; Akimoto, Tetsuo

2017-01-01

To clarify the efficacy and toxicity of post-mastectomy radiation therapy (PMRT) without usage of a bolus, we identified 129 consecutive patients who received PMRT at the National Cancer Center Hospital East between 2003 and 2012. Seven of the 129 patients who received breast reconstruction before PMRT were excluded. All patients received PMRT of 6 MV photons, without usage of a bolus. The median follow-up duration for all eligible patients was 47.7 months (range: 4.0–123.2). Local, locoregional and isolated locoregional recurrence was found in 12 (9.8%), 14 (11%) and 5 patients (4.1%), respectively. The 3- and 5-year cumulative incidence of local recurrence, locoregional recurrence and isolated locoregional recurrence was 9.2 and 10.7%, 10.8 and 12.4%, and 4.3 and 4.3%, respectively. Although Grade 2 dermatitis was found in 11 patients (9.0%), no Grade 3–4 dermatitis was found. On univariate analysis, only a non-luminal subtype was a significant predictor for local recurrence (P < 0.001). On multivariate analysis, a non-luminal subtype remained as an independent predictor for local recurrence (P = 0.003, odds ratio: 10.9, 95% confidence interval: 2.23–53.1). In conclusion, PMRT without usage of a bolus resulted in a low rate of severe acute dermatitis without an apparent increase in local recurrence. PMRT without usage of a bolus may be reasonable, especially for patients with a luminal subtype.

The velocity of a radioactive bolus in the oesophagus evaluated by means of an image segmentation algorithm

International Nuclear Information System (INIS)

Miquelin, Charlie A; Dantas, Roberto O; Oliveira, Ricardo B; Braga, Francisco Jos H. N

2002-01-01

Classical scintigraphic evaluation of a radioactive bolus through the oesophagus is based on regions of interest and time/activity curves, which only gives information about the total time required for it to cross the organ. Instantaneous parameters can be obtained if the exact position (centroid) of the bolus is known. For that, one needs to know the co-ordinates of the centre of mass of the bolus radioactivity distribution. From this, one can obtain velocity at each time. Obtaining such a new parameter would be important, to try to determine whether the anatomical differences among the 3 thirds of the oesophagus have a functional correspondence or not. We have studied 5 normal volunteers (4 males, 1 female, 33-68 yo). Each volunteer swallowed (unique swallowing) 40 MBq of 99mTc-phytate in 10 ml water. Eighty frames (0.3 sec) were acquired in a scintillation camera. External marks were used to separate the pharynx from the oesophagus. Images were transformed into bitmap by means of a Sophy Medical processing module and analysed by means of the algorithm, which determines the co-ordinates of the centroid (horizontal and vertical) for each frame and instant velocities through the organ. Different velocities were found in typical evaluations. Curves representing the different positions of the bolus C and the correspondent different Vs were obtained. Different velocities of the bolus were detected during the pharyngeal phase, and proximal, mid and distal parts of the oesophagus. Larger studies are necessary, but it seems that the velocity of a radioactive bolus changes in the different parts of the oesophagus. It is reasonable to say that there is a functional correspondence to the anatomical differences in the organ (Au)

WE-F-16A-05: Use of 3D-Printers to Create a Tissue Equivalent 3D-Bolus for External Beam Therapy

Energy Technology Data Exchange (ETDEWEB)

Burleson, S; Baker, J; Hsia, A; Xu, Z [Stony Brook Medicine, Stony Brook, NY (United States)

2014-06-15

Purpose: The purpose of this project is to demonstrate that a non-expensive 3D-printer can be used to manufacture a 3D-bolus for external beam therapy. The printed bolus then can be modeled in our treatment planning system to ensure accurate dose delivery to the patient. Methods: We developed a simple method to manufacture a patient-specific custom 3Dbolus. The bolus is designed using Eclipse Treatment Planning System, contoured onto the patients CT images. The bolus file is exported from Eclipse to 3D-printer software, and then printed using a 3D printer. Various tests were completed to determine the properties of the printing material. Percent depth dose curves in this material were measured with electron and photon beams for comparison to other materials. In order to test the validity of the 3D printed bolus for treatment planning, a custom bolus was printed and tested on the Rando phantom using film for a dose plane comparison. We compared the dose plane measured on the film to the same dose plane exported from our treatment planning system using Film QA software. The gamma-dose distribution tool was used in our film analysis. Results: We compared point measurements throughout the dose plane and were able to achieve greater than 95% passing rate at 3% dose difference and 3 mm distance to agreement, which is our departments acceptable gamma pixel parameters. Conclusion: The printed 3D bolus has proven to be accurately modeled in our treatment planning system, it is more conformal to the patient surface and more durable than other bolus currently used (wax, superflab etc.). It is also more convenient and less costly than comparable bolus from milling machine companies.

WE-F-16A-05: Use of 3D-Printers to Create a Tissue Equivalent 3D-Bolus for External Beam Therapy

International Nuclear Information System (INIS)

Burleson, S; Baker, J; Hsia, A; Xu, Z

2014-01-01

Purpose: The purpose of this project is to demonstrate that a non-expensive 3D-printer can be used to manufacture a 3D-bolus for external beam therapy. The printed bolus then can be modeled in our treatment planning system to ensure accurate dose delivery to the patient. Methods: We developed a simple method to manufacture a patient-specific custom 3Dbolus. The bolus is designed using Eclipse Treatment Planning System, contoured onto the patients CT images. The bolus file is exported from Eclipse to 3D-printer software, and then printed using a 3D printer. Various tests were completed to determine the properties of the printing material. Percent depth dose curves in this material were measured with electron and photon beams for comparison to other materials. In order to test the validity of the 3D printed bolus for treatment planning, a custom bolus was printed and tested on the Rando phantom using film for a dose plane comparison. We compared the dose plane measured on the film to the same dose plane exported from our treatment planning system using Film QA software. The gamma-dose distribution tool was used in our film analysis. Results: We compared point measurements throughout the dose plane and were able to achieve greater than 95% passing rate at 3% dose difference and 3 mm distance to agreement, which is our departments acceptable gamma pixel parameters. Conclusion: The printed 3D bolus has proven to be accurately modeled in our treatment planning system, it is more conformal to the patient surface and more durable than other bolus currently used (wax, superflab etc.). It is also more convenient and less costly than comparable bolus from milling machine companies

Optimizing computed tomography pulmonary angiography using right atrium bolus monitoring combined with spontaneous respiration

Energy Technology Data Exchange (ETDEWEB)

Min, Wang; Jian, Li; Rui, Zhai [Jining No. 1 People' s Hospital, Department of Computed Tomography, Jining City, ShanDong Province (China); Wen, Li [Jining No. 1 People' s Hospital, Department of Gastroenterology, Jining, ShanDong (China); Dai, Lun-Hou [Shandong Chest Hospital, Department of Radiology, Jinan, ShanDong (China)

2015-09-15

CT pulmonary angiography (CTPA) aims to provide pulmonary arterial opacification in the absence of significant pulmonary venous filling. This requires accurate timing of the imaging acquisition to ensure synchronization with the peak pulmonary artery contrast concentration. This study was designed to test the utility of right atrium (RA) monitoring in ensuring optimal timing of CTPA acquisition. Sixty patients referred for CTPA were divided into two groups. Group A (n = 30): CTPA was performed using bolus triggering from the pulmonary trunk, suspended respiration and 70 ml of contrast agent (CA). Group B (n = 30): CTPA image acquisition was triggered using RA monitoring with spontaneous respiration and 40 ml of CA. Image quality was compared. Subjective image quality, average CT values of pulmonary arteries and density difference between artery and vein pairs were significantly higher whereas CT values of pulmonary veins were significantly lower in group B (all P < 0.05). There was no significant difference between the groups in the proportion of subjects where sixth grade pulmonary arteries were opacified (P > 0.05). RA monitoring combined with spontaneous respiration to trigger image acquisition in CTPA produces optimal contrast enhancement in pulmonary arterial structures with minimal venous filling even with reduced doses of CA. (orig.)

Cardiac T1 mapping in congenital heart disease: bolus vs. infusion protocols for measurements of myocardial extracellular volume fraction.

Science.gov (United States)

Al-Wakeel-Marquard, Nadya; Rastin, Sanaz; Muench, Frédéric; O H-Ici, Darach; Yilmaz, Sevim; Berger, Felix; Kuehne, Titus; Messroghli, Daniel R

2017-12-01

Myocardial extracellular volume fraction (ECV) reflecting diffuse myocardial fibrosis can be measured with T1 mapping cardiovascular magnetic resonance (CMR) before and after the application of a gadolinium-based extracellular contrast agent. The equilibrium between blood and myocardium contrast concentration required for ECV measurements can be obtained with a primed contrast infusion (equilibrium contrast-CMR). We hypothesized that equilibrium can also be achieved with a single contrast bolus to accurately measure diffuse myocardial fibrosis in patients with congenital heart disease (CHD). Healthy controls (n = 17; median age 24.0 years) and patients with CHD (n = 19; 25.0 years) were prospectively enrolled. Using modified Look-Locker inversion recovery T1 mapping before, 15 min after bolus injection, and during constant infusion of gadolinium-DOTA, T1 values were obtained for blood pool and myocardium of the left ventricle (LV), the interventricular septum (IVS), and the right ventricle (RV) in a single midventricular plane in short axis or in transverse orientation. ECV of LV, IVS and RV by bolus-only and bolus-infusion correlated significantly in CHD patients (r = 0.94, 0.95, and 0.74; p < 0.01, respectively) and healthy controls (r = 0.96, 0.89, and 0.64; p < 0.05, respectively). Bland-Altman plots revealed no significant bias between the techniques for any of the analyzed regions. ECV of LV and RV myocardium measured by bolus-only T1 mapping agrees well with bolus-infusion measurements in patients with CHD. The use of a bolus-only approach facilitates the integration of ECV measurements into existing CMR imaging protocols, allowing for assessment of diffuse myocardial fibrosis in CHD in clinical routine.

Anxiety can significantly explain bolus perception in the context of hypotensive esophageal motility: Results of a large multicenter study in asymptomatic individuals.

Science.gov (United States)

Cisternas, D; Scheerens, C; Omari, T; Monrroy, H; Hani, A; Leguizamo, A; Bilder, C; Ditaranto, A; Ruiz de León, A; Pérez de la Serna, J; Valdovinos, M A; Coello, R; Abrahao, L; Remes-Troche, J; Meixueiro, A; Zavala, M A; Marin, I; Serra, J

2017-09-01

Previous studies have not been able to correlate manometry findings with bolus perception. The aim of this study was to evaluate correlation of different variables, including traditional manometric variables (at diagnostic and extreme thresholds), esophageal shortening, bolus transit, automated impedance manometry (AIM) metrics and mood with bolus passage perception in a large cohort of asymptomatic individuals. High resolution manometry (HRM) was performed in healthy individuals from nine centers. Perception was evaluated using a 5-point Likert scale. Anxiety was evaluated using Hospitalized Anxiety and Depression scale (HAD). Subgroup analysis was also performed classifying studies into normal, hypotensive, vigorous, and obstructive patterns. One hundred fifteen studies were analyzed (69 using HRM and 46 using high resolution impedance manometry (HRIM); 3.5% swallows in 9.6% of volunteers were perceived. There was no correlation of any of the traditional HRM variables, esophageal shortening, AIM metrics nor bolus transit with perception scores. There was no HRM variable showing difference in perception when comparing normal vs extreme values (percentile 1 or 99). Anxiety but not depression was correlated with perception. Among hypotensive pattern, anxiety was a strong predictor of variance in perception (R 2 up to .70). Bolus perception is less common than abnormal motility among healthy individuals. Neither esophageal motor function nor bolus dynamics evaluated with several techniques seems to explain differences in bolus perception. Different mechanisms seem to be relevant in different manometric patterns. Anxiety is a significant predictor of bolus perception in the context of hypotensive motility. © 2017 John Wiley & Sons Ltd.

Evaluation of the esophagus with a marshmallow bolus: clarifying the cause of dysphagia.

Science.gov (United States)

Ott, D J; Kelley, T F; Chen, M Y; Gelfand, D W

1991-01-01

We reviewed the radiographic examinations of the esophagus and medical records in 117 patients (55 women and 62 men; mean age, 52 years) in which a marshmallow bolus was also given. A one-third to one-half piece of a standard marshmallow was used with a mean size of 23 mm (+/- 4.5 mm SD) measured in vivo. In 62 patients with no intrinsic structural narrowing of the esophagus, impaction occurred in only seven (11%). Four of these patients had an esophageal motility disorder, and three had a previous Nissen fundoplication. The remaining 55 patients had lower esophageal mucosal rings (47) or peptic strictures (8). Marshmallow impaction was seen in 27 of 47 rings (57%) and was inversely related to ring size, and in six of eight strictures (75%). Also, impaction was related to the ratio of bolus size to ring caliber, and invariably occurred when this ratio was greater than 1.5. Dysphagia was the presenting complaint in 76 (65%) patients, but was found equally in those without intrinsic narrowing and in those with ring or stricture. However, dysphagia was reproduced by the marshmallow bolus only in patients with esophageal narrowing or abnormal motility.

Replacement of oxytocin bolus administration by infusion: influences on postpartum outcome.

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Löytved-Hardegg, Julia J; Brunner, Mirjam; Ries, Jean-Jacques; von Felten, Stefanie; Heugel, Christina; Lapaire, Olav; Voekt, Cora; Hösli, Irene

2016-06-01

Postpartum haemorrhage (PPH) represents a leading cause of maternal morbidity and mortality. Giving oxytocin after birth reduces the risk for PPH. It has never been tested whether different methods of oxytocin administration affect the maternal outcome. This study aims to compare the infusion versus the bolus application of oxytocin after singleton vaginal delivery. This retrospective monocentre study compares the incidence of clinically relevant postpartum complications in women receiving 5 IE of oxytocin as a bolus or as a 100 ml-infusion over 5 min, given immediately after birth. Included were women delivering singletons vaginally at term. We used propensity score weighting to compare outcomes between women receiving bolus and infusion and to minimize the selection bias in this retrospective cohort. 1765 patients were included. Patient characteristics were balanced. We found no significant differences for the combined overall postpartum adverse outcome (the incidence of PPH, manual removal of the placenta and/or curettage). For the single outcomes, we observed a significantly higher frequency of manual removal of the placenta (Odds ratio 1.47, 95 % CI 1.02-2.13) and a slightly higher but clinically not relevant estimated blood loss (Relative effect 1.05, 95 % CI 1.01-1.10) in the infusion group. The data show a tendency towards more complications in the infusion group. It is related to a more frequent need for manual removal of the placenta.

Continuous indomethacin infusion may be less effective than bolus infusions for ductal closure in very low birth weight infants

NARCIS (Netherlands)

de Vries, NKS; Jagroep, FK; Jaarsma, AS; Elzenga, NJ; Bos, AF

The effectiveness of continuous indomethacin (INDO) infusion versus bolus infusions for closure of patent ductus arteriosus (PDA) was investigated. The study design was an open-label case series (continuous INDO) with historic controls matched for gestational age (bolus INDO). Ductal closure rates

Implementation of a split-bolus single-pass CT protocol at a UK major trauma centre to reduce excess radiation dose in trauma pan-CT

International Nuclear Information System (INIS)

Leung, V.; Sastry, A.; Woo, T.D.; Jones, H.R.

2015-01-01

Aim: To quantify the dose reduction and ensure that the use of a split-bolus protocol provided sufficient vascular enhancement. Materials and methods: Between 1 January 2014 and 31 May 2014, both split bolus and traditional two-phase scans were performed on a single CT scanner (SOMATOM Definition AS+, Siemens Healthcare) using a two-pump injector (Medrad Stellant). Both protocols used Siemens' proprietary tube current and tube voltage modulation techniques (CARE dose and CARE kV). The protocols were compared retrospectively to assess the dose–length product (DLP), aortic radiodensity at the level of the coeliac axis and radiodensity of the portal vein. Results: There were 151 trauma CT examinations during this period. Seventy-eight used the split-bolus protocol. Seventy-one had traditional two-phase imaging. One patient was excluded as they were under the age of 18 years. The radiodensity measurements for the portal vein were significantly higher (p<0.001) in the split-bolus protocol. The mean aortic enhancement in both protocols exceeded 250 HU, although the traditional two-phase protocol gave greater arterial enhancement (p<0.001) than the split-bolus protocol. The split-bolus protocol had a significantly lower (p<0.001) DLP with 43.5% reduction in the mean DLP compared to the traditional protocol. Conclusion: Split-bolus CT imaging offers significant dose reduction for this relatively young population while retaining both arterial and venous enhancement. -- Highlights: •We implemented a split bolus pan-CT protocol for trauma CT. •We compared the radiation dose and vascular enhancement of the split bolus protocol to a traditional two phase protocol. •The split bolus protocol had a 43.5% reduction in mean DLP

Comparison of Bolus Phenylephrine, Ephedrine and Mephentermine for Maintenance of Arterial Pressure during Spinal Anesth

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B Bhattarai

2010-03-01

Full Text Available INTRODUCTION: Hypotension is common following spinal anesthesia. Various vasopressors have been indicated to prevent it. The study compares three such agents namely phenylephrine, ephedrine and mephentermine. METHODS: The study included 90 patients undergoing elective and emergency cesarean section who developed hypotension following subarachnoid blockade. Parturient were randomly divided into three groups each group had 30 patients. Group P received bolus of Phenylephrine 25 microgram, where as group E received Ephedrine 5mg and Group M received Mephentermine 6mg. RESULTS: It was found that rise of blood pressure was significantly higher in case of phenylephrine group in first six minutes, after the bolus, there was significant reduction in the heart rate in phenylephrine group, but there was tachycardia following administration of bolus ephedrine and mephenteramine. Neonatal APGAR score were similar in all three groups. CONCLUSIONS: All three drugs maintained hemodynamics within 20 percent of the baseline values on intravenous administration. Keywords: APGAR, ephedrine, hypotension, mephentermine, phenylephrine, spinal anesthesia.

"The relationship between pharmacokinetic variables and pharmacodynamic profiles of bolus versus continuous infusion of furosemide in critically ill patients"

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"Mojtaba Mojtahedzadeh

2005-05-01

Full Text Available In this investigation, the pharmacokinetic variables of continuous infusion and intermittent bolus injection of furosemide and the possible relationship between its pharmacokinetic characteristics and pharmacodynamic profile among intensive care unit (ICU patients were studied. In this prospective, randomized, clinical trial, twelve patients received IV bolus of 20 mg of the drug during 3 hours period and, the drug dose was doubled, when the urine output was less than 1 ml/kg/h (group 1. The other nine patients received a continuous intravenous furosemide infusion at the rate of 0.1 mg/kg/h (group 2. The amount of furosemide in serum was measured by high performance liquid chromatography (HPLC. Results showed a positive correlation between plasma clearance of furosemide and its diuretic activity (P=0.01. The pharmacokinetic parameters such as Vd (l, CL (ml/min, Ke (min-1 and t½ (min in continuous infusion patients were not significantly differed from the bolus patients (P-values 0.5, 0.9, 0.9,0.9, respectively. Nevertheless the observed plasma clearance of drug in the continuous infusion group was clinically higher than bolus injection group and as a result the cumulative urine output per hour per mg of furosemide in a continuous infusion was observed to be higher than bolus(P=0.2. Changes in serum sodium and potassium were similar for both groups, but bolus injection patients were associated with higher potassium depletion (P=0.001. Therefore, continuous infusion seems to be better means of diuretic therapy in critically ill patients.

Rapid Bolus Administration Does not Increase The Extravasation Rate of Albumin: A Randomized Controlled Trial in The Endotoxemic Pig.

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von Seth, Magnus; Lipcsey, Miklós; Engström, Peter; Larsson, Anders; Hillered, Lars; Maripuu, Enn; Widström, Charles; Sjölin, Jan

2017-04-01

Some experimental data suggest that rapid bolus administration of albumin causes less plasma-expanding effects than slow, continuous infusion. To determine whether rapid bolus administration, in comparison with slow infusion, results in greater extravasation of albumin in experimental septic shock we performed a randomized controlled trial with 32 endotoxemic pigs. The animals were monitored and ventilated with standard intensive care equipment and given 10 mL × kg 5% albumin labeled with Technetium-99m, either as a rapid 15-min bolus (Bolus group, n = 16) or as a 2-h infusion (Infusion group, n = 16). Radioactivity was monitored in plasma, extracellular microdialysate, and urine for 6 h. Physiological parameters were monitored hourly. Radioactivity in the liver, spleen, kidney, and lung was analyzed post mortem.The plasma area under the curve activity0-6 h was 4.4 ± 0.9 × 10 in the Bolus group and 4.4 ± 1.1 × 10 counts × min × mL × h in the Infusion group. Blood hemoglobin levels increased in both groups, suggesting severe capillary leakage. Yet, there were no group differences in albumin radioactivity in plasma, muscle tissue, urine, or in the post-mortem analysis of the organs. Following albumin administration, circulatory and respiratory parameters were similar in the two groups.In conclusion, the present results suggest that albumin might be given as a bolus without leading to increased extravasation of albumin, in contrast to previous animal experiments in rodents.

Solution or suspension - Does it matter for lipid based systems? In vivo studies of chase dosing lipid vehicles with aqueous suspensions of a poorly soluble drug.

Science.gov (United States)

Larsen, A T; Holm, R; Müllertz, A

2017-08-01

In this study, the potential of co-administering an aqueous suspension with a placebo lipid vehicle, i.e. chase dosing, was investigated in rats relative to the aqueous suspension alone or a solution of the drug in the lipid vehicle. The lipid investigated in the present study was Labrafil M2125CS and three evaluated poorly soluble model compounds, danazol, cinnarizine and halofantrine. For cinnarizine and danazol the oral bioavailability in rats after chase dosing or dosing the compound dissolved in Labrafil M21515CS was similar and significantly higher than for the aqueous suspension. For halofantrine the chase dosed group had a tendency towards a low bioavailability relative to the Labrafil M2125CS solution, but still a significant higher bioavailability relative to the aqueous suspension. This could be due to factors such as a slower dissolution rate in the intestinal phase of halofantrine or a lower solubility in the colloidal structures formed during digestion, but other mechanisms may also be involved. The study thereby supported the potential of chase dosing as a potential dosing regimen in situations where it is beneficial to have a drug in the solid state, e.g. due to chemical stability issues in the lipid vehicle. Copyright © 2017 Elsevier B.V. All rights reserved.

Normal mediastinal and hilar lymph nodes evaluated by 5 mm slice bolus injection CT scan

International Nuclear Information System (INIS)

Yamamoto, Takako; Tsukada, Hiroshi; Koizumi, Naoya; Akita, Shinichi; Oda, Junichi; Sakai, Kunio

1995-01-01

We evaluated the number and size of normal mediastinal and hilar lymph nodes by 5 mm slice bolus injection CT (12 patients), compared with 10 mm slice CT (12 patients). More lymph nodes were clearly demonstrated by 5 mm slice CT than by 10 mm slice CT. Especially left-sided tracheobronchial (no.4), subaortic (no.5), subcarinal (no.7) and hilar lymph nodes were clearly visible. We concluded 5 mm slice bolus injection CT was useful to evaluate mediastinal and hilar lymph nodes. (author)

A backprojection-filtration algorithm for nonstandard spiral cone-beam CT with an n-PI-window

International Nuclear Information System (INIS)

Yu Hengyong; Ye Yangbo; Zhao Shiying; Wang Ge

2005-01-01

For applications in bolus-chasing computed tomography (CT) angiography and electron-beam micro-CT, the backprojection-filtration (BPF) formula developed by Zou and Pan was recently generalized by Ye et al to reconstruct images from cone-beam data collected along a rather flexible scanning locus, including a nonstandard spiral. A major implication of the generalized BPF formula is that it can be applied for n-PI-window-based reconstruction in the nonstandard spiral scanning case. In this paper, we design an n-PI-window-based BPF algorithm, and report the numerical simulation results with the 3D Shepp-Logan phantom and Defrise disk phantom. The proposed BPF algorithm consists of three steps: cone-beam data differentiation, weighted backprojection and inverse Hilbert filtration. Our simulated results demonstrate the feasibility and merits of the proposed algorithm

Should colloid boluses be prioritized over crystalloid boluses for the management of dengue shock syndrome in the presence of ascites and pleural effusions?

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Weerasinghe Mindu

2011-02-01

Full Text Available Abstract Background Although the WHO guideline for the management of dengue fever considers the presence of ascites or pleural effusions in the diagnosis of DSS, it does not emphasize the importance of their presence when selecting fluids for resuscitation. Case presentation We highlight three patients with DSS who received boluses of crystalloids on priority basis as recommended by WHO guidelines during resuscitation. All three patients had varying degrees of third space fluid loss (ascites and pleural effusions at the time of development of DSS. Ascites and pleural effusions were detected in all 3 patients at the time of shock irrespective of whether iv fluids were given or not. All three patients had documented liver involvement at the time of shock evidenced by elevation of AST (4800 iu/L, 5000 iu/L and 1960 iu/L. One patient who had profound shock died 6 hours after admission with evidence of acute pulmonary oedema in the convalescence phase. All of them needed CPAP ventilator support and potent diuretics. Conclusions We therefore feel that resuscitation of patients with DSS who already have third space fluid accumulation with crystalloid boluses on priority basis may contribute to recovery phase pulmonary oedema.

21 CFR 520.1720a - Phenylbutazone tablets and boluses.

Science.gov (United States)

2010-04-01

... Section 520.1720a Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...-mg or 1-g tablets, or 2- or 4-g boluses, in dogs and horses. (2) Nos. 000010 and 059130 for use of 100- or 200-mg or 1-g tablets in dogs and horses. (3) Nos. 000856 and 061623 for use of 100-mg or 1-g...

Continuous transversus abdominis plane block vs intermittent bolus for analgesia after abdominal surgery: a randomized trial

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Rao Kadam V

2017-07-01

Full Text Available Vasanth Rao Kadam,1 Roelof M Van Wijk,1 John L Moran,2 Shantan Ganesh,3 A Kumar,1 Rajesh Sethi,1 Patricia Williams2,4 1Department of Anaesthesia, The Queen Elizabeth Hospital, School of Medicine, University of Adelaide, Adelaide, SA, 2Intensive Care Unit, The Queen Elizabeth Hospital, School of Medicine, University of Adelaide, Adelaide, SA, 3Department of Surgery, The Queen Elizabeth Hospital, School of Medicine, University of Adelaide, Adelaide, SA, 4Department of Epidemiology and Preventive Medicine, School Public Health and Preventive Medicine, Australian and New Zealand Intensive Care Research Centre, Monash University, Melbourne, VIC, Australia Background: Continuous and intermittent bolus techniques of transversus abdominis plane (TAP blocks have been used for analgesia after abdominal surgery. Although both are effective, there are no studies comparing them. The aim of this study is to compare analgesia and cost-effectiveness between these groups.Methods: After obtaining ethical approval, 20 American Society of Anesthesiologists ASA grade I to III patients undergoing elective abdominal surgery were recruited with 10 patients allocated to each arm. Bilateral ultrasound-guided TAP blocks were performed with an initial bolus of 0.5% ropivacaine 20 mL per side, followed by catheter insertion. After surgery, the continuous infusion group received 0.2% ropivacaine 8 mL/hour on each side and the intermittent bolus group received doses of 0.2% ropivacaine 20 mL per side every 8 hours for 48 hours. Both groups received intravenous fentanyl patient-controlled analgesia and regular oral paracetamol. Parameters recorded included numerical rating scores for pain and post-operative analgesic consumption at baseline (time 0 and at 1 hour, 1 day and 2 days post-operatively. The duration of catheter insertion, complications, patient satisfaction and information regarding costs were also recorded. Patient satisfaction was assessed utilizing a 4-point �

INFLUENCE OF AGE ON SWALLOWS OF A HIGHLY VISCOUS LIQUID BOLUS

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Weslania Viviane NASCIMENTO

2015-03-01

Full Text Available Background Swallow function has a decline with aging, mainly in those over 80 years old. In the population over 69 years, about 11% of subjects reported symptoms indicative of significant dysphagia. Objectives Our objective was to evaluate the hypothesis that older asymptomatic subjects before 80 years old have compensations to sustain a safe and efficient swallow, at least with swallows of liquid bolus. Methods We performed videofluoroscopic evaluation of swallows in 55 normal volunteers, a younger group with 33 subjects (16 men and 17 women aged 19 to 55 years, mean 35.5±9.8 years, and an older group with 22 subjects (15 men and 7 women aged 56 to 77 years, mean 64.8±6.8 years. The subjects swallowed in duplicate 5 mL and 10 mL of liquid barium with a pH of 7.9, density of 1.82 g/cm3, and viscosity of 895 cp. Results The mean duration of pharyngeal transit, pharyngeal clearance, upper esophageal sphincter opening, hyoid movement and oral-pharyngeal transit were longer in the younger group compared with the older group. The relation between pharyngeal clearance duration and hyoid movement duration was similar in younger and older subjects, for 5 mL and 10 mL bolus volumes. Conclusions On average, a highly viscous liquid bolus crosses the pharynx faster in older subjects (56-77 years old than in younger subjects (19-55 years old, which suggested an adaptation to the aging process to maintain a safe swallow.

The influence of a slow-release multi-trace element ruminal bolus on trace element status, number of ovarian follicles and pregnancy outcomes in synchronized Afshari ewes

Science.gov (United States)

Abdollahi, E.; Kohram, H.; Shahir, M. H.; Nemati, M. H.

2015-01-01

Published data on the effects of ruminal bolus on the number of ovulatory follicles in ewes does not exist. The present study determined the effects of a ruminal bolus on trace element status, follicular dynamics and reproductive performance in ewes. Eighty Afshari cycling ewes were synchronized during breeding season using CIDR for 14 days and assigned to 4 groups (n=20); group 1 received a single Ferrobloc bolus four weeks prior to CIDR insertion following 400 IU eCG on CIDR removal, group 2 received two boluses four weeks prior to CIDR insertion following 400 IU eCG on CIDR removal, group 3 received only 400 IU eCG on CIDR removal and group 4 (control) received no bolus and no eCG. Transrectal ultrasonography was done to monitor the ovarian follicles on the day of CIDR removal and a day later. Results showed that boluses increased the status of copper, selenium and iodine on mating day and days 90 to 100 of gestation. Ruminal bolus did not significantly increase the number of different classes of ovarian follicles in ewes fed a diet meeting all trace mineral requirements. All ewes eventually became pregnant with 1 or 2 boluses but the multiple births rate (80%) was higher (P<0.05) after 2 boluses compared to the other groups. PMID:27175153

Bolus fluid therapy and sodium homeostasis in paediatric gastroenteritis.

Science.gov (United States)

Freedman, Stephen B; Geary, Denis F

2013-03-01

The study aims to assess the risk of developing hyponatraemia when large-volume bolus fluid rehydration therapy is administered. We conducted a prospective randomised study in a tertiary-care centre emergency department. Participants included children with gastroenteritis and dehydration requiring intravenous rehydration. They were randomised to receive 60 mL/kg (large) or 20 mL/kg (standard) 0.9% saline bolus followed by maintenance 0.9% saline for 3 h. Biochemical tests were performed at baseline and 4 h. The primary outcome measure was the development of hyponatraemia at 4 h. Secondary outcome measures were (i) change in sodium relative to baseline value; (ii) magnitude of decrease among those who experienced a decrease; (iii) risk of hypernatraemia; (iv) correlations between urine parameters and hyponatraemia; and (v) fluid overload. Eighty-four of 224 (38%) participants were hyponatraemic at baseline. At 4 h, 22% (48/217) had a dysnatraemia, and similar numbers of children were hyponatraemic in both groups: large (23% (26/112)) versus standard (21% (22/105)) (P = 0.69). Among initially hyponatraemic children, 63% (30/48) who received large-volume rehydration and 44% (15/34) of those administered standard rehydration were isonatraemic at 4 h (P = 0.10). Overall, children who received 60 mL/kg experienced a larger mean increase (1.6 ± 2.4 mEq/L vs. 0.9 ± 2.2 mEq/L; P = 0.04) and were less likely to experience a sodium decrease of ≥2 mEq/L (8/112 vs. 17/105; P = 0.04) than those administered 20 mL/kg. Large-volume bolus rehydration therapy with 0.9% saline is safe. It does not promote the development of hyponatraemia over the short term, but hastens the resolution of baseline hyponatraemia. © 2013 The Authors. Journal of Paediatrics and Child Health © 2013 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

Behaviorism Makes Its Debut: A Review of Lattal and Chase's Behavior Theory and Philosophy

OpenAIRE

Zuriff, G.E

2005-01-01

Behavior Theory and Philosophy, masterfully edited by Lattal and Chase, is a collection of 21 papers by major behaviorists, presented and discussed at a conference on the intersection of philosophy and behavior analysis held at West Virginia University in 2000. The chapters in Part I are devoted to philosophy of science (causality, constructs, theory, explanation, reductionism) and the relations among behavior analysis and several contemporary philosophical movements (humanism, empiricism, pr...

Comparison between intravenous boluses versus infusion of tranexamic acid (TXA) to reduce bleeding in paediatric cyanotic congenital heart disease (CHD) surgeries

International Nuclear Information System (INIS)

Junejo, F.; Irfan, M.; Akhtar, M.I.; Hamid, M.; Ahmed, S.S.

2018-01-01

To compare the intravenous boluses and intravenous continuous infusion of tranexamic acid (TXA) to reduce postoperative bleeding in cyanotic congenital heart disease surgeries. Study Design:Single-blinded randomised clinical trial. Place and Duration of Study:Anaesthesia Department, The Aga Khan University Hospital, Karachi, from July 2016 to April 2017. Methodology:Sixty patients of cyanotic congenital heart disease, undergoing either palliative or corrective surgery involving cardiopulmonary bypass (CPB), were recruited. These 60 patients were divided randomly into two groups. The infusion group received intravenous infusion of TXA at 5 mg/kg/hour while the bolus group received three intravenous boluses of 10 mg/kg after induction, after going to bypass and after protamine reversal. Data was collected through predesigned proforma. There were two primary outcomes: postoperative bleeding in the first 24 hours, and chest closure time. Results:Postoperative bleeding was 13.94 (10.27-20.18) ml/kg in the first 24 hours in infusion group and 15.05 (9.04-23.50) ml/kg in the bolus group. Chest closure time was 38.5 (25-45) in infusion group and 30 (20-46.25) minutes in the bolus group. There was no statistically significant and clinical difference between both groups regarding postoperative bleeding in the first 24 hours and chest closure time. Conclusion:These infusion and bolus groups had comparable postoperative bleeding and chest closure time. (author)

76 FR 31955 - Jonathan and Jayne Chase; Notice of Application Accepted for Filing With the Commission, Intent...

Science.gov (United States)

2011-06-02

.... c. Date filed: July 23, 2010. d. Applicant: Jonathan and Jayne Chase. e. Name of Project: Troy Hydropower Project. f. Location: On the Missisquoi River, in the Town of Troy, Orleans County, Vermont. The... filing and is now ready for environmental analysis. l. Project Description: The Troy Project would...

Pharmacokinetics of rocuronium after bolus and continuous infusion during halothane anaesthesia

NARCIS (Netherlands)

McCoy, E.P; Mirakhur, R.K; Maddineni, V.R; Wierda, J.MKH; Proost, Hans

We have studied the pharmacokinetics of a single bolus of rocuronium (Org 9426), followed by an infusion, in eight patients during anaesthesia with halothane and nitrous oxide in oxygen. Neuromuscular block was monitored using train-of-four (TOF) stimulation and recording the force of contraction of

The Effect of Bolus Volume on Hyoid Kinematics in Healthy Swallowing

Directory of Open Access Journals (Sweden)

Ahmed Nagy

2014-01-01

Full Text Available Hyoid movement in swallowing is biomechanically linked to closure of the laryngeal vestibule for airway protection and to opening of the upper esophageal sphincter. Studies suggest that the range of hyoid movement is highly variable in the healthy population. However, other aspects of hyoid movement such as velocity remain relatively unexplored. In this study, we analyze data from a sample of 20 healthy young participants (10 male to determine whether hyoid movement distance, duration, velocity, and peak velocity vary systematically with increases in thin liquid bolus volume from 5 to 20 mL. The temporal correspondence between peak hyoid velocity and laryngeal vestibule closure was also examined. The results show that maximum hyoid position and peak velocity increase significantly for 20 mL bolus volumes compared to smaller volumes, and that the timing of peak velocity is closely linked to achieving laryngeal vestibule closure. This suggests that generating hyoid movements with increased power is a strategy for handling larger volumes.

Enteral nutrition for preterm infants: by bolus or continuous? An update

Directory of Open Access Journals (Sweden)

Valentina Bozzetti

2017-06-01

Full Text Available Optimization of nutritional management of preterm infants is crucial for achievement of their long-term health. Enteral nutrition is preferred to total parenteral nutrition (TPN because the former avoids complications related to vascular catheterization, sepsis, adverse effects of TPN, and fasting. Due to the lack of ability of preterm infants to coordinate suckling, swallowing, and breathing, tube feeding is necessary for most infants less than 1500 g to ensure sufficient feeding tolerance, to support optimal growth and to reduce the risk of aspiration. Therefore, feeding by orogastric or nasogastric tube using either continuous or intermittent bolus delivery of formula or human milk is common practice for these infants. Theoretical risks and benefits of both continuous nasogastric milk feeding and intermittent bolus milk feeding have been proposed. According to the literature, continuous nutrition could be preferred in smaller infants (as those with a birthweight below 1250 g or hemodynamically impaired infants; in stable growing infants nutrition can be administered intermittently as in healthy term infants.

Effects of copper oxide wire particle bolus therapy on trichostrongyle fecal egg counts in exotic artiodactylids.

Science.gov (United States)

Fontenot, Deidre K; Kinney-Moscona, Allyson; Kaplan, Ray M; Miller, James

2008-12-01

Four species of artiodactylids (scimitar-horned oryx [Oryx dama]), roan antelope [Hippotragus equinus], blackbuck [Antilope cervicapra]), and blesbok [Damaliscus pygargus phillipsi]) totaling 13 animals were treated with a one-time 12.5-g dose of copper oxide wire particles (COWPs) in a bolus form. Pretreatment, individual trichostrongyle fecal egg counts (FECs) were performed using the McMaster technique. Individual posttreatment FECs were performed every 7 days for 35 days beginning 7 days after bolus administration, and FEC reduction ratios (FECRRs) expressed as percentage reductions from pretreatment values were calculated every 7 days. Mean FECRRs for the 13 animals were 93% +/- 16%, 98% +/- 7%, 91% +/- 28%, 94% +/- 16%, and 90% +/- 13% at 7, 14, 21, 28, and 35 days posttreatment, respectively. These data demonstrate that COWPs in a bolus form were an effective method for reducing FEC in exotic artiodactylids. Based on this limited data, COWPs show promise as an anthelmintic alternative for exotic artiodactylids in zoologic collections.

Turnover rates in microorganisms by laser ablation electrospray ionization mass spectrometry and pulse-chase analysis

Energy Technology Data Exchange (ETDEWEB)

Stopka, Sylwia A.; Mansour, Tarek R.; Shrestha, Bindesh [Department of Chemistry, W.M. Keck Institute for Proteomics Technology and Applications, The George Washington University, Washington, DC 20052 (United States); Maréchal, Éric; Falconet, Denis [Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, CEA-CNRS-INRA-Univ. Grenoble Alpes, Grenoble (France); Vertes, Akos, E-mail: vertes@gwu.edu [Department of Chemistry, W.M. Keck Institute for Proteomics Technology and Applications, The George Washington University, Washington, DC 20052 (United States)

2016-01-01

Biochemical processes rely on elaborate networks containing thousands of compounds participating in thousands of reaction. Rapid turnover of diverse metabolites and lipids in an organism is an essential part of homeostasis. It affects energy production and storage, two important processes utilized in bioengineering. Conventional approaches to simultaneously quantify a large number of turnover rates in biological systems are currently not feasible. Here we show that pulse-chase analysis followed by laser ablation electrospray ionization mass spectrometry (LAESI-MS) enable the simultaneous and rapid determination of metabolic turnover rates. The incorporation of ion mobility separation (IMS) allowed an additional dimension of analysis, i.e., the detection and identification of isotopologs based on their collision cross sections. We demonstrated these capabilities by determining metabolite, lipid, and peptide turnover in the photosynthetic green algae, Chlamydomonas reinhardtii, in the presence of {sup 15}N-labeled ammonium chloride as the main nitrogen source. Following the reversal of isotope patterns in the chase phase by LAESI-IMS-MS revealed the turnover rates and half-lives for biochemical species with a wide range of natural concentrations, e.g., chlorophyll metabolites, lipids, and peptides. For example, the half-lives of lyso-DGTS(16:0) and DGTS(18:3/16:0), t{sub 1/2} = 43.6 ± 4.5 h and 47.6 ± 2.2 h, respectively, provided insight into lipid synthesis and degradation in this organism. Within the same experiment, half-lives for chlorophyll a, t{sub 1/2} = 24.1 ± 2.2 h, and a 2.8 kDa peptide, t{sub 1/2} = 10.4 ± 3.6 h, were also determined. - Highlights: • High-throughput pulse-chase analysis using direct sampling of biological cells. • Ion mobility separation for the elucidation of isotopologs. • Identification of isotopologs in difference heat plots of DT vs. m/z. • Simultaneous determination of turnover rates for lipids and

Low contrast volume run-off CT angiography with optimized scan time based on double-level test bolus technique – feasibility study

International Nuclear Information System (INIS)

Baxa, Jan; Vendiš, Tomáš; Moláček, Jiří; Štěpánková, Lucie; Flohr, Thomas; Schmidt, Bernhard; Korporaal, Johannes G.; Ferda, Jiří

2014-01-01

Purpose: To verify the technical feasibility of low contrast volume (40 mL) run-off CT angiography (run-off CTA) with the individual scan time optimization based on double-level test bolus technique. Materials and methods: A prospective study of 92 consecutive patients who underwent run-off CTA performed with 40 mL of contrast medium (injection rate of 6 mL/s) and optimized scan times on a second generation of dual-source CT. Individual optimized scan times were calculated from aortopopliteal transit times obtained on the basis of double-level test bolus technique – the single injection of 10 mL test bolus and dynamic acquisitions in two levels (abdominal aorta and popliteal arteries). Intraluminal attenuation (HU) was measured in 6 levels (aorta, iliac, femoral and popliteal arteries, middle and distal lower-legs) and subjective quality (3-point score) was assessed. Relations of image quality, test bolus parameters and arterial circulation involvement were analyzed. Results: High mean attenuation (HU) values (468; 437; 442; 440; 342; 274) and quality score in all monitored levels was achieved. In 91 patients (0.99) the sufficient diagnostic quality (score 1–2) in aorta, iliac and femoral arteries was determined. A total of 6 patients (0.07) were not evaluable in distal lower-legs. Only the weak indirect correlation of image quality and test-bolus parameters was proved in iliac, femoral and popliteal levels (r values: −0.263, −0.298 and −0.254). The statistically significant difference of the test-bolus parameters and image quality was proved in patients with occlusive and aneurysmal disease. Conclusion: We proved the technical feasibility and sufficient quality of run-off CTA with low volume of contrast medium and optimized scan time according to aortopopliteal transit time calculated from double-level test bolus

The influence of carbon monoxide bolus on the measurement of total haemoglobin mass using the optimized CO-rebreathing method

International Nuclear Information System (INIS)

Turner, G; Richardson, A J; Maxwell, N S; Pringle, J S M; Ingham, S A; Fudge, B W

2014-01-01

The optimized carbon monoxide (CO) rebreathing method (oCOR-method) is routinely used to measure total haemoglobin mass (tHbmass). The tHbmass measure is subject to a test-retest typical error of ∼2%, mostly from the precision of carboxyhaemoglobin (HbCO) measurement. We hypothesized that tHbmass would be robust to differences in the bolus of CO administered during the oCOR-method. Twelve participants (ten males and two females; age 27 ± 6 yr, height 177 ± 11 cm and mass 73.9 ± 12.1 kg) completed the oCOR-method on four occasions. Different bolus of CO were administered (LOW: 0.6 ml kg −1 ; MED 1 : 1.0 ml kg −1  and HIGH: 1.4 ml kg −1 ); to determine the reliability of MED 1 , a second trial was conducted (MED 2 ). tHbmass was found to be significantly less from the HIGH CO bolus (776 ± 148 g) when compared to the LOW CO (791 ± 149 g) or MED 1  CO (788 ± 149 g) trials. MED 2  CO was 785 ± 150 g. The measurement of tHbmass is repeatable to within 0.8%, but a small and notable difference was seen when using a HIGH CO bolus (1.4 to 1.9% less), potentially due to differences in CO uptake kinetics. Previously, an improved precision of the oCOR-method was thought to require a higher bolus of CO (i.e. larger ▵%HbCO), as commercial hemoximeters only estimate %HbCO levels to a single decimal place (usually ± 0.1%). With the new hemoximeter used in this study, a bolus of 1.0 ml kg −1  allows adequate precision with acceptable safety. (note)

Differential Response Pattern of Oropharyngeal Pressure by Bolus and Dry Swallows.

Science.gov (United States)

Hasegawa, Mana; Kurose, Masayuki; Okamoto, Keiichiro; Yamada, Yoshiaki; Tsujimura, Takanori; Inoue, Makoto; Sato, Taisuke; Narumi, Takatsune; Fujii, Noritaka; Yamamura, Kensuke

2018-02-01

The aim of this study was to determine if bolus and dry swallow showed similar pressure changes in the oropharynx using our newly developed device. A unique character of it includes that baropressure can be measured with the sensor being placed in the balloon and can assess the swallowing mechanics in terms of pressure changes in the oropharynx with less influences of direct contacts of boluses and oropharyngeal structures during swallow indirectly. Fifteen healthy subjects swallowed saliva (dry), 15 ml of water, 45 ml of water, and 15 ml of two different types of food in terms of viscosity (potage soup-type and mayonnaise-type foods). Suprahyoid muscle activity was recorded simultaneously. Three parameters, area under the curve (AUC), peak amplitude, and duration of pressure, were analyzed from each swallow. Almost all of the bolus swallowing events had biphasic baropressure responses consisting of an early phase and late phase (99%), whereas 90% of the saliva swallowing events had a single phase. AUC, peak, and duration displayed greater effects during the late phase than during the early phase. Baropressure of the early phase, but not of the late phase, significantly increased with increasing volume; however, small but significant viscosity effects on pressure were seen during both phases. Peak pressure of the late phase was preceded by maximum muscle activity, whereas that of the early phase was seen when muscle activity displayed a peak response. These findings indicated that our device with the ability to measure baropressure has the potential to provide additional parameter to assess the swallow physiology, and biphasic baropressure responses in the early and late phases could reflect functional aspects of the swallowing reflexes.

Multi-detector row CT of the kidney: Optimizing scan delays for bolus tracking techniques of arterial, corticomedullary, and nephrographic phases

Energy Technology Data Exchange (ETDEWEB)

Goshima, Satoshi [Department of Radiology, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1193 (Japan); Kanematsu, Masayuki [Department of Radiology, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1193 (Japan); Department of Radiology Services, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1193 (Japan); Nishibori, Hironori; Kondo, Hiroshi; Tsuge, Yusuke [Department of Radiology, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1193 (Japan); Yokoyama, Ryujiro; Miyoshi, Toshiharu [Department of Radiology Services, Gifu University School of Medicine, 1-1 Yanagido, Gifu 501-1193 (Japan); Onozuka, Minoru [Department of Physiology and Neuroscience, Kanagawa Dental College, Yokosuka, Kanagawa (Japan); Shiratori, Yoshimune [Department of Medical Informatics, Gifu University School of Medicine, Gifu (Japan); Moriyama, Noriyuki [Department of Diagnostic Radiology, National Cancer Center Hospital, Tsukiji, Chuo-Ku, Tokyo (Japan); Bae, Kyongtae T. [Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO (United States)

2007-09-15

Purpose: To determine optimal scan delays for renal arterial-, corticomedullary-, and nephrographic-phase imaging with multi-detector row computed tomography (MDCT) of the kidney using a bolus-tracking technique. Methods and materials: One hundred and twenty-eight patients underwent three-phase CT scan of the kidney with eight-row MDCT after receiving 2 mL/kg of 300 mg I/mL contrast medium at 4 mL/s. Patients were prospectively randomized into three groups with different scan delays for the three scan phases (arterial, corticomedullary, and nephrographic) after bolus-tracking triggered at 50 HU of aortic contrast enhancement: group 1 (5, 20, 45 s); group 2 (10, 25, 50 s); and group 3 (15, 30, 55 s). Mean CT values (HU) of the abdominal aorta, renal artery, renal vein, renal cortex, and renal medulla were measured; increases in CT values pre- to post-contrast were assessed as contrast enhancement. Renal artery-to-vein and renal cortex-to-medulla contrast differences were also assessed. Qualitative analysis was also performed. Results: Mean renal artery enhancement was 240-288 HU at 5-15 s after the trigger and peaked at 10 s (P < .001). Mean renal cortical enhancement was 195-217 HU at 10-30 s and peaked at 25 s (P < .01). Contrast enhancement in the renal medulla increased gradually and reached mean 145 HU at 55 s. Cortex-to-medulla contrast difference was high (110-140 HU) at 5-30 s and decreased below 30 HU at 45 s after the trigger. Renal artery-to-vein contrast difference was high (121-125 HU) at 5-10 s. Qualitative results correlated well with quantitative results. Conclusion: For the injection protocol used in this study, optimal scan delays after the bolus-tracking trigger were 5-10 s for renal arterial, 15-25 s for corticomedullary, and 50-55 s for nephrographic phases.

Poster - 38: On the physical and dosimetric properties of 3D printed electron bolus fabricated using polylactic acid

Energy Technology Data Exchange (ETDEWEB)

Sasaki, David; Jensen, Martin; Rickey, Daniel W; Dubey, Arbind; Harris, Chad; McCurdy, Boyd [CancerCare Manitoba, CancerCare Manitoba, CancerCare Manitoba, CancerCare Manitoba, CancerCare Manitoba, CancerCare Manitoba (Canada)

2016-08-15

Purpose: 3D printing technology could simplify and improve electron bolus fabrication. The purpose of this study was to characterize the density, dimensional accuracy, uniformity, and attenuation of PLA boluses fabricated with a low-cost 3D printer. Methods: Several solid square slabs were printed with specific requested dimensions and 100% infill using different fill patterns. These pieces were imaged using an x-ray flat panel imager in order to check for uniformity of the prints. Percentage depth doses (PDDs) were measured downstream of the slabs in solid water using a parallel plate chamber and compared to measurements in water in order to characterize attenuation. The dimensions of the PLA slabs were measured using digital calipers. The slabs were also weighed to find their density. Results: The fill pattern used to create boluses can affect the attenuation of the bolus. Fill patterns should be chosen carefully and quality assurance should be done for each printed piece. PLA causes the electron PDD to shift towards shallower depths, compared to water, by 1.7 mm for each centimeter of PLA. Agreement with design dimensions was within 1 mm in the plane of the printer bed, and within 1/3 of a millimeter (roughly the thickness of a single layer), perpendicular to the printer bed. Average density was in the range 1.20 – 1.22. Conclusions: 3D printing shows great promise for use in fabricating electron bolus. This work indicates that printed PLA can be a suitable material provided the increased attenuation is properly accounted for.

Poster - 38: On the physical and dosimetric properties of 3D printed electron bolus fabricated using polylactic acid

International Nuclear Information System (INIS)

Sasaki, David; Jensen, Martin; Rickey, Daniel W; Dubey, Arbind; Harris, Chad; McCurdy, Boyd

2016-01-01

Purpose: 3D printing technology could simplify and improve electron bolus fabrication. The purpose of this study was to characterize the density, dimensional accuracy, uniformity, and attenuation of PLA boluses fabricated with a low-cost 3D printer. Methods: Several solid square slabs were printed with specific requested dimensions and 100% infill using different fill patterns. These pieces were imaged using an x-ray flat panel imager in order to check for uniformity of the prints. Percentage depth doses (PDDs) were measured downstream of the slabs in solid water using a parallel plate chamber and compared to measurements in water in order to characterize attenuation. The dimensions of the PLA slabs were measured using digital calipers. The slabs were also weighed to find their density. Results: The fill pattern used to create boluses can affect the attenuation of the bolus. Fill patterns should be chosen carefully and quality assurance should be done for each printed piece. PLA causes the electron PDD to shift towards shallower depths, compared to water, by 1.7 mm for each centimeter of PLA. Agreement with design dimensions was within 1 mm in the plane of the printer bed, and within 1/3 of a millimeter (roughly the thickness of a single layer), perpendicular to the printer bed. Average density was in the range 1.20 – 1.22. Conclusions: 3D printing shows great promise for use in fabricating electron bolus. This work indicates that printed PLA can be a suitable material provided the increased attenuation is properly accounted for.

The reliability and validity of passive leg raise and fluid bolus to assess fluid responsiveness in spontaneously breathing emergency department patients

DEFF Research Database (Denmark)

Duus, Nicolaj; Shogilev, Daniel J; Skibsted, Simon

2015-01-01

PURPOSE: We investigated the reproducibility of passive leg raise (PLR) and fluid bolus (BOLUS) using the Non-Invasive Cardiac Output Monitor (NICOM; Cheetah Medical, Tel Aviv, Israel) for assessment of fluid responsiveness (FR) in spontaneously breathing emergency department (ED) patients. METHODS...

Use of an automated bolus calculator in MDI-treated type 1 diabetes

DEFF Research Database (Denmark)

Schmidt, Signe; Meldgaard, Merete; Serifovski, Nermin

2012-01-01

To investigate the effect of flexible intensive insulin therapy (FIIT) and an automated bolus calculator (ABC) in a Danish type 1 diabetes population treated with multiple daily injections. Furthermore, to test the feasibility of teaching FIIT in a 3-h structured course....

Distribution and mixing of a liquid bolus in pleural space.

Science.gov (United States)

Bodega, Francesca; Tresoldi, Claudio; Porta, Cristina; Zocchi, Luciano; Agostoni, Emilio

2006-02-28

Distribution and mixing time of boluses with labeled albumin in pleural space of anesthetized, supine rabbits were determined by sampling pleural liquid at different times in various intercostal spaces (ics), and in cranial and caudal mediastinum. During sampling, lung and chest wall were kept apposed by lung inflation. This was not necessary in costo-phrenic sinus. Here, 10 min after injection, lung inflation increased concentration of labeled albumin by 50%. Lung inflation probably displaces some pleural liquid cranio-caudally, increasing labeled albumin concentration caudally to injection point (6th ics), and decreasing it cranially. Boluses of 0.1-1 ml did not preferentially reach mediastinal regions, as maintained by others. Time for an approximate mixing was approximately 1 h for 0.1 ml, and approximately 30 min for 1 ml. This relatively long mixing time does not substantially affect determination of contribution of lymphatic drainage through stomata to overall removal of labeled albumin from 0.3 ml hydrothoraces lasting 3 h [Bodega, F., Agostoni, E., 2004. Contribution of lymphatic drainage through stomata to albumin removal from pleural space. Respir. Physiol. Neurobiol. 142, 251-263].

Comparison of bolus versus fractionated oral applications of [13C]-linoleic acid in humans.

Science.gov (United States)

Demmelmair, H; Iser, B; Rauh-Pfeiffer, A; Koletzko, B

1999-07-01

The endogenous conversion of linoleic acid into long-chain polyunsaturated fatty acids is of potential importance for meeting substrate requirements, particularly in young infants. After application of [13C]-linoleic acid, we estimated its conversion to dihomo-gamma-linolenic and arachidonic acids from only two blood samples. Oral tracer doses were given to five healthy adults as a single bolus. In four subjects the tracer was given in nine equal portions over 3 days. Concentration and 13C content of fatty acids from serum phospholipids were analysed by gas chromatography combustion isotope ratio-mass spectrometry. Areas under the tracer-concentration curves were calculated, and fractional transfer and turnover rates estimated from compartmental models. The median fractional turnover of linoleic acid was 93.7% per day (interquartile range 25.3) in the bolus group and 80. 0% per day (6.3) in the fraction group (NS). Fractional conversion of linoleic to dihomo-gamma-linolenic acid was 1.5% (0.9) vs. 2.1% (0.7) (bolus vs. fraction, P /= 0.94, P < 0.05) with the ratio of areas under the curve. Using areas under the curve overestimates the conversion, because different residence times are not considered. Estimation of conversion intensity appears possible with only one blood sample obtained after tracer application.

Biosynthesis of intestinal microvillar proteins. Pulse-chase labelling studies on maltase-glucoamylase, aminopeptidase A and dipeptidyl peptidase IV

DEFF Research Database (Denmark)

Danielsen, E M; Sjöström, H; Norén, Ove

1983-01-01

The biogenesis of three intestinal microvillar enzymes, maltase-glucoamylase (EC 3.2.1.20), aminopeptidase A (aspartate aminopeptidase, EC 3.4.11.7) and dipeptidyl peptidase IV (EC 3.4.14.5), was studied by pulse-chase labelling of pig small-intestinal explants kept in organ culture. The earliest...

Feasibility of test-bolus DCE-MRI using CAIPIRINHA-VIBE for the evaluation of pancreatic malignancies

Energy Technology Data Exchange (ETDEWEB)

Huh, Jimi; Seo, Nieun; Kim, Bohyun [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, 88 Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Choi, Yoonseok; Woo, Dong-Cheol; Lee, Chang Kyung [Asan Medical Center, Bioimaging Center, Asan Institute for Life Sciences, Seoul (Korea, Republic of); Kim, In Seong [Siemens Healthcare, Seoul (Korea, Republic of); Nickel, Dominik [Siemens Healthcare, Erlangen (Germany); Kim, Kyung Won [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, 88 Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Asan Medical Center, Bioimaging Center, Asan Institute for Life Sciences, Seoul (Korea, Republic of)

2016-11-15

To evaluate the feasibility of test-bolus dynamic contrast-enhanced (DCE) MRI with CAIPIRINHA-VIBE for pancreatic malignancies. Thirty-two patients underwent DCE-MRI with CAIPIRINHA-VIBE after injection of 2 mL gadolinium. From the resulting time-intensity curve (TIC), we estimated the arterial (AP) and portal venous phase (PVP) scan timing for subsequent multiphasic MRI. DCE-MRI perfusion maps were generated, and perfusion parameters were calculated. The image quality was rated on a 5-point scale (1: poor, 5: excellent). Goodness-of-fit of the TIC was evaluated by Pearson's χ{sup 2} test. Test-bolus DCE-MRIs with high temporal (3 s) and spatial resolution (1 x 1 x 4 mm{sup 3}) were acquired with good-quality perfusion maps of Ktrans and iAUC (mean score 4.313 ± 0.535 and 4.125 ± 0.554, respectively). The mean χ{sup 2} values for fitted TICs were 0.115 ± 0.082 for the pancreatic parenchyma and 0.784 ± 0.074 for pancreatic malignancies, indicating an acceptable goodness-of-fit. Test-bolus DCE-MRI was highly accurate in estimating the proper timing of AP (90.6 %) and PVP (100 %) of subsequent multiphasic MRI. Between pancreatic adenocarcinomas and neuroendocrine tumours, there were significant differences in the Ktrans (0.073 ± 0.058 vs. 0.308 ± 0.062, respectively; p = 0.007) and iAUC (1.501 ± 0.828 vs. 3.378 ± 0.378, respectively; p = 0.045). Test-bolus DCE-MRI using CAIPIRINHA-VIBE is feasible for incorporating perfusion analysis of pancreatic tumours into routine multiphasic MRI. (orig.)

The neutron therapy facility at the University of Pennsylvania-Fox Chase Cancer Center

International Nuclear Information System (INIS)

Bloch, P.; Chu, J.; Larsen, R.

1983-01-01

The fusion of deuterium and tritium nuclei results in the formation of a helium-4 nucleus and a 14 MEV neutron. This reaction readily takes place when deuterium and tritium ions are accelerated to potentials between 150-200 kV. These energy ions can be obtained in a moderate size accelerator. A DT neutron facility has been installed in the radiation therapy department of the University of Pennsylvania Hospital-Fox Chase Cancer Center. The system is being commissioned in a hospital setting to test the efficacy of fast neutron radiotherapy

Comparison of Power Versus Manual Injection in Bolus Shape and Image Quality on Contrast-Enhanced Magnetic Resonance Angiography: An Experimental Study in a Swine Model.

Science.gov (United States)

Tsuboyama, Takahiro; Jost, Gregor; Pietsch, Hubertus; Tomiyama, Noriyuki

2017-09-01

The aim of this study was to compare power versus manual injection in bolus shape and image quality on contrast-enhanced magnetic resonance angiography (CE-MRA). Three types of CE-MRA (head-neck 3-dimensional [3D] MRA with a test-bolus technique, thoracic-abdominal 3D MRA with a bolus-tracking technique, and thoracic-abdominal time-resolved 4-dimensional [4D] MRA) were performed after power and manual injection of gadobutrol (0.1 mmol/kg) at 2 mL/s in 12 pigs (6 sets of power and manual injections for each type of CE-MRA). For the quantitative analysis, the signal-to-noise ratio was measured on ascending aorta, descending aorta, brachiocephalic trunk, common carotid artery, and external carotid artery on the 6 sets of head-neck 3D MRA, and on ascending aorta, descending aorta, brachiocephalic trunk, abdominal aorta, celiac trunk, and renal artery on the 6 sets of thoracic-abdominal 3D MRA. Bolus shapes were evaluated on the 6 sets each of test-bolus scans and 4D MRA. For the qualitative analysis, arterial enhancement, superimposition of nontargeted enhancement, and overall image quality were evaluated on 3D MRA. Visibility of bolus transition was assessed on 4D MRA. Intraindividual comparison between power and manual injection was made by paired t test, Wilcoxon rank sum test, and analysis of variance by ranks. Signal-to-noise ratio on 3D MRA was statistically higher with power injection than with manual injection (P < 0.001). Bolus shapes (test-bolus, 4D MRA) were represented by a characteristic standard bolus curve (sharp first-pass peak followed by a gentle recirculation peak) in all the 12 scans with power injection, but only in 1 of the 12 scans with manual injection. Standard deviations of time-to-peak enhancement were smaller in power injection than in manual injection. Qualitatively, although both injection methods achieved diagnostic quality on 3D MRA, power injection exhibited significantly higher image quality than manual injection (P = 0.001) due to

Bolus and continuous infusion mitoxantrone in newly diagnosed adult acute lymphoblastic leukemia: results of two consecutive phase II clinical studies.

Science.gov (United States)

Koc, Y; Akpek, G; Kansu, E; Kars, A; Tekuzman, G; Baltali, E; Güler, N; Barista, I; Güllü, I; Ozisik, Y; Firat, D

1998-01-01

Two consecutive phase II clinical studies were designed to evaluate the efficacy and safety of bolus and continuous infusion (CI) mitoxantrone (MTZ) in 39 patients with newly diagnosed acute lymphocytic leukemia (ALL). MTZ was used as part of the classical ALL induction regimen. Twenty patients were treated with bolus MTZ (10 mg/m2 for 3 days) combined with vincristine and prednisone. The same regimen was given to a second set of 19 patients, except that MTZ was administered as a 24-hr CI. Both groups received bimonthly intensifications with vincristine and prednisone for 3 years, along with oral maintenance therapy. Patients in the CI-MTZ study arm received additional MTZ on the first day of intensification cycles. Seventeen patients (85%) in the bolus arm and 15 patients (79%) in the CI arm achieved complete remission (CR). Median disease-free survivals (DFS) in the bolus and CI groups were 11 and 15 months after median follow-ups of 16 (3.5-96) and 13 (2.3-32) months, respectively. At 2.5 years, DFS rates were 29.4% and 34.4% in the bolus and CI groups (p > 0.05). There were no significant differences between two groups in rates of early death, degree of organ toxicity, or duration of neutropenia and thrombocytopenia. Significant cardiac toxicity was not observed in either group. Bolus or CI administration of MTZ was equally effective and was well tolerated. Neither the mode of administration nor increasing the dose intensity of MTZ by incorporating intensification cycles reduced relapse rates. Development of new antileukemia agents and novel treatment approaches are still needed to improve the high relapse rates in adult ALL once a complete response is achieved.

Factors Influencing ACT After Intravenous Bolus Administration of 100 IU/kg of Unfractionated Heparin During Cardiac Catheterization in Children.

Science.gov (United States)

Muster, Ileana; Haas, Thorsten; Quandt, Daniel; Kretschmar, Oliver; Knirsch, Walter

2017-10-01

Anticoagulation using intravenous bolus administration of unfractionated heparin (UFH) aims to prevent thromboembolic complications in children undergoing cardiac catheterization (CC). Optimal UFH dosage is needed to reduce bleeding complications. We analyzed the effect of bolus UFH on activated clotting time (ACT) in children undergoing CC focusing on age-dependent, anesthesia-related, or disease-related influencing factors. This retrospective single-center study of 183 pediatric patients receiving UFH during CC analyzed ACT measured at the end of CC. After bolus administration of 100 IU UFH/kg body weight, ACT values between 105 and 488 seconds were reached. Seventy-two percent were within target level of 160 to 240 seconds. Age-dependent differences were not obtained ( P = .407). The ACT values were lower due to hemodilution (total fluid and crystalloid administration during CC, both P ACT values but occurred more frequently in children between 1 month and 1 year of age (91%). In conclusion, with a bolus of 100 IU UFH/kg, an ACT target level of 160 to 240 seconds can be achieved during CC in children in 72%, which is influenced by hemodilution and anticoagulant and antiplatelet premedication but not by age.

Methods in computed angiotomography of the brain

International Nuclear Information System (INIS)

Yamamoto, Yuji; Asari, Shoji; Sadamoto, Kazuhiko.

1985-01-01

Authors introduce the methods in computed angiotomography of the brain. Setting of the scan planes and levels and the minimum dose bolus (MinDB) injection of contrast medium are described in detail. These methods are easily and safely employed with the use of already propagated CT scanners. Computed angiotomography is expected for clinical applications in many institutions because of its diagnostic value in screening of cerebrovascular lesions and in demonstrating the relationship between pathological lesions and cerebral vessels. (author)

Precision flow-controlled rubidium-82 generator for bolus and constant infusion studies

International Nuclear Information System (INIS)

Yano, Y.

1981-01-01

A unique flow rate controller and large reservoir pumping system have been developed for infusing rubidium-82 intravenously at bolus, constant, or variable infusion rates. Using rubidium-82 and the positron ring detector tomograph, extraction or flow information can be obtained in studies of the heart, head, or kidneys

Adductor Canal Block With Continuous Infusion Versus Intermittent Boluses and Morphine Consumption

DEFF Research Database (Denmark)

Jaeger, Pia; Baggesgaard, Jonas; Sørensen, Johan K

2018-01-01

a randomized, blinded, controlled study, including patients scheduled for total knee arthroplasty with spinal anesthesia. Patients received 0.2% ropivacaine via a catheter in the adductor canal administered as either repeated intermittent boluses (21 mL/3 h) or continuous infusion (7 mL/h). The primary outcome...

[Multispiral computed tomographic semiotics of laryngeal cancer].

Science.gov (United States)

Vasil'ev, P V; Iudin, A L; Sdvizhkov, A M; Kozhanov, L G

2007-01-01

Multispiral computed tomography (MSCT) with intravenous bolus contrasting is a currently available method for radiodiagnosis of laryngeal cancer. MSCT is of much higher informative value in estimating the extent of a tumorous lesion than the traditional radiodiagnostic techniques: linear tomography, lateral X-ray study, roentgenoscopy and roentgenography of the laryngopharynx and esophagus with barium meal.

Use of 3D printers to create a patient‐specific 3D bolus for external beam therapy

Science.gov (United States)

Baker, Jamie; Hsia, An Ting; Xu, Zhigang

2015-01-01

The purpose of this paper is to demonstrate that an inexpensive 3D printer can be used to manufacture patient‐specific bolus for external beam therapy, and to show we can accurately model this printed bolus in our treatment planning system for accurate treatment delivery. Percent depth‐dose measurements and tissue maximum ratios were used to determine the characteristics of the printing materials, acrylonitrile butadiene styrene and polylactic acid, as bolus material with physical density of 1.04 and 1.2 g/cm3, and electron density of 3.38×1023electrons/cm3 and 3.80×1023 electrons/cm3, respectively. Dose plane comparisons using Gafchromic EBT2 film and the RANDO phantom were used to verify accurate treatment planning. We accurately modeled a printing material in Eclipse treatment planning system, assigning it a Hounsfield unit of 260. We were also able to verify accurate treatment planning using gamma analysis for dose plane comparisons. With gamma criteria of 5% dose difference and 2 mm DTA, we were able to have 86.5% points passing, and with gamma criteria of 5% dose difference and 3 mm DTA, we were able to have 95% points passing. We were able to create a patient‐specific bolus using an inexpensive 3D printer and model it in our treatment planning system for accurate treatment delivery. PACS numbers: 87.53.Jw, 87.53.Kn, 87.56.ng PMID:26103485

Tolerance to continuous intrathecal baclofen infusion can be reversed by pulsatile bolus infusion

NARCIS (Netherlands)

Heetla, H. W.; Staal, M. J.; van Laar, T.

Study design: Pilot study. Objective: To study the effect of pulsatile bolus infusion of intrathecal baclofen (ITB) on daily ITB dose, in patients showing dose increases, probably due to tolerance. Setting: Department of neurology and neurosurgery, University Medical Center Groningen, the

Initiation of simian virus 40 DNA replication in vitro: Pulse-chase experiments identify the first labeled species as topologically unwound

International Nuclear Information System (INIS)

Bullock, P.A.; Seo, Yeon Soo; Hurwitz, J.

1989-01-01

A distinct unwound form of DNA containing the simian virus 40 (SV40) origin is produced in replication reactions carried out in mixtures containing crude fractions prepared from HeLa cells. This species, termed form U R , comigrates on chloroquine-containing agarose gels with the upper part of the previously described heterogeneous highly unwound circular DNA, form U. As with form U, formation of form U R is dependent upon the SV40 tumor (T) antigen. Pulse-chase experiments demonstrate that the first species to incorporate labeled deoxyribonucleotides comigrates with form U R . Restriction analyses of the products of the pulse-chase experiments show that initiation occurs at the SV40 origin and then proceeds outward in a bidirectional manner. These experiments establish form U R as the earliest detectable substrate for SV40 DNA replication and suggest that SV40 DNA replication initiates on an unwound species

SU-F-T-86: Electron Dosimetric Effects of Bolus and Lens Shielding in Treating Superficial Eye Lesions

Energy Technology Data Exchange (ETDEWEB)

Young, L [University of Washington Medical Center, Seattle, WA (United States); Wootton, L [University of Washington School of Medicine, Seattle, WA (United States); Gopan, O; Liao, J [University of Washington, Seattle, WA (United States)

2016-06-15

Purpose: Electron therapy for the treatment of ocular lymphomas requires the lens to be shielded to prevent secondary cataracts. This work evaluates the dosimetry under a suspended eyeshield with and without bolus for low energy electron fields. Methods: Film (GafChromic EBT3) dosimetry and relative output factors were measured for 6, 8, and 10 MeV electron energies. A customized 5 cm diameter circle electron orbital cutout was constructed for a 6×6 cm applicator with a lens shield, 1 cm diameter Cerrobend cylinder with 2.2 cm length, suspended from an XV film covering the open field. Relative output factors were measured using a Scanditronix electron diode in a solid water phantom. Depth dose profiles were collected for bolus thicknesses of 0, 3, and 5 mm in solid water at a source to surface distance (SSD) of 100 cm. These measurements were repeated in a Rando phantom. Results: At 5 mm, the approximate distance of the lens from the surface of the cornea, the estimated dose in solid water under the suspended lens shield was reduced to 16%, 14%, and 13% of the unblocked dose at the same depth, for electron energies of 6, 8, and 10 MeV, respectively. Applying bolus increased estimated doses under the block to 22% for 3-mm and 32% for 5-mm thicknesses for a 6 MeV incident electron beam. This effect is reduced for higher energies where the corresponding values were 15.5% and 18% for 3-mm and 5-mm for an 8 MeV electron beam. Conclusion: The application of bolus to treat superficial eye lesions of the conjunctiva increases lens dose at a depth of 5-mm under the shielding block with decreasing electron energy. Careful selection of electron energy is needed to account for electron scatter under the lens shield with the application of bolus in order to prevent cataracts.

The effect of food bolus location on jaw movement smoothness and masticatory efficiency.

Science.gov (United States)

Molenaar, W N B; Gezelle Meerburg, P J; Luraschi, J; Whittle, T; Schimmel, M; Lobbezoo, F; Peck, C C; Murray, G M; Minami, I

2012-09-01

Masticatory efficiency in individuals with extensive tooth loss has been widely discussed. However, little is known about jaw movement smoothness during chewing and the effect of differences in food bolus location on movement smoothness and masticatory efficiency. The aim of this study was to determine whether experimental differences in food bolus location (anterior versus posterior) had an effect on masticatory efficiency and jaw movement smoothness. Jaw movement smoothness was evaluated by measuring jerk-cost (calculated from acceleration) with an accelerometer that was attached to the skin of the mentum of 10 asymptomatic subjects, and acceleration was recorded during chewing on two-colour chewing gum, which was used to assessed masticatory efficiency. Chewing was performed under two conditions: posterior chewing (chewing on molars and premolars only) and anterior chewing (chewing on canine and first premolar teeth only). Jerk-cost and masticatory efficiency (calculated as the ratio of unmixed azure colour to the total area of gum, the unmixed fraction) were compared between anterior and posterior chewing with the Wilcoxon signed rank test (two-tailed). Subjects chewed significantly less efficiently during anterior chewing than during posterior chewing (P = 0·0051). There was no significant difference in jerk-cost between anterior and posterior conditions in the opening phase (P = 0·25), or closing phase (P = 0·42). This is the first characterisation of the effect of food bolus location on jaw movement smoothness at the same time as recording masticatory efficiency. The data suggest that anterior chewing decreases masticatory efficiency, but does not influence jerk-cost. © 2012 Blackwell Publishing Ltd.

The effect of food bolus location on jaw movement smoothness and masticatory efficiency

NARCIS (Netherlands)

Molenaar, W.N.B.; Gezelle Meerburg, P.J.; Luraschi, J.; Whittle, T.; Schimmel, M.; Lobbezoo, F.; Peck, C.C.; Murray, G.M.; Minami, I.

2012-01-01

Masticatory efficiency in individuals with extensive tooth loss has been widely discussed. However, little is known about jaw movement smoothness during chewing and the effect of differences in food bolus location on movement smoothness and masticatory efficiency. The aim of this study was to

Amniotic fluid index predicts the relief of variable decelerations after amnioinfusion bolus.

Science.gov (United States)

Spong, C Y; McKindsey, F; Ross, M G

1996-10-01

Our purpose was to determine whether intrapartum amniotic fluid index before amnioinfusion can be used to predict response to therapeutic amnioinfusion. Intrapartum patients (n = 85) with repetitive variable decelerations in fetal heart rate that necessitated amnioinfusion (10 ml/min for 60 minutes) underwent determination of amniotic fluid index before and after bolus amnioinfusion. The fetal heart tracing was scored (scorer blinded to amniotic fluid index values) for number and characteristics of variable decelerations before and 1 hour after initiation of amnioinfusion. The amnioinfusion was considered successful if it resulted in a decrease of > or = 50% in total number of variable decelerations or a decrease of > or = 50% in the rate of atypical or severe variable decelerations after administration of the bolus. Spontaneous vaginal births before completion of administration of the bolus (n = 18) were excluded from analysis. The probability of success of amnioinfusion in relation to amniotic fluid index was analyzed with the chi(2) test for progressive sequence. The mean amniotic fluid index before amnioinfusion was 6.2 +/- 3.3 cm. An amniotic fluid index of amnioinfusion decreased with increasing amniotic fluid index before amnioinfusion (76% [16/21] when initial amniotic fluid index was 0 to 4 cm, 63% [17/27] when initial amniotic fluid index was 4 to 8 cm, 44% [7/16] when initial amniotic fluid index was 8 to 12 cm, and 33% [1/3] when initial amniotic fluid index was > 12 cm, p = 0.03). The incidence of nuchal cords or true umbilical cord knots increased in relation to amniotic fluid index before amnioinfusion. Amniotic fluid index before amnioinfusion can be used to predict the success of amnioinfusion for relief of variable decelerations in fetal heart rate. Failure of amnioinfusion at a high amniotic fluid index before amnioinfusion may be explained by the increased prevalence of nuchal cords or true knots in the umbilical cord.

Continuous versus bolus intragastric tube feeding for preterm and low birth weight infants with gastro-oesophageal reflux disease.

Science.gov (United States)

Richards, Robyn; Foster, Jann P; Psaila, Kim

2014-07-17

Gastro-oesophageal reflux disease is a particularly common condition in preterm and low birth weight infants. These infants are also more likely to have excessive regurgitation, as they do not have a fully developed antireflux mechanism. Preterm and low birth weight infants who are unable to suck oral feeds are required to be fed via an intragastric tube for varying lengths of time. Intragastric tube feeding can be delivered by the intermittent bolus or continuous feeding method. Use of continuous or intermittent bolus intragastric feeding may have a positive or negative effect on the incidence or severity of gastro-oesophageal reflux disease. To determine whether continuous or intermittent bolus intragastric tube feeding reduces the number of episodes and the duration of gastro-oesophageal reflux disease (GORD) in preterm and low birth weight infants.We intended to perform subgroup analyses for gestational age; birth weight; age in days from birth at full enteral feeding via intragastric tube (breast vs bottle); frequency of intermittent bolus feed; and type of medication for treatment of GORD (only if medication prescribed and given similarly to both intervention groups). We used the standard search strategy of the Cochrane Neonatal Group as described in The Cochrane Library (www.thecochranelibrary.com) to search for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 9), MEDLINE (1966 to September 2013), EMBASE (1980 to September 2013) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982 to September 2013). We also searched previous reviews, including cross-references, abstracts and conference and symposia proceedings of the Perinatal Society of Australia and New Zealand and the Pediatric Academic Societies (American Pediatric Society/Society for Pediatric Research and European Society for Paediatric Research) from 1990 to 2012. Published and unpublished RCTs and quasi

The cost-effectiveness and budget impact of stepwise addition of bolus insulin in the treatment of type 2 diabetes: evaluation of the FullSTEP trial.

Science.gov (United States)

Saunders, Rhodri; Lian, Jean; Karolicki, Boris; Valentine, William

2014-12-01

Abstract Background and aims: Intensification of basal insulin-only therapy in type 2 diabetes is often achieved through addition of bolus insulin 3-times daily. The FullSTEP trial demonstrated that stepwise addition (SWA) of bolus insulin aspart was non-inferior to full basal-bolus (FBB) therapy and reduced the rate of hypoglycemia. Here the cost-effectiveness and budget impact of SWA is evaluated. Cost-effectiveness and budget impact models were developed to assess the cost and quality-of-life (QoL) implications of intensification using SWA compared with FBB in the US setting. At assessment, SWA patients added one bolus dose to their current regimen if the HbA1c target was not met. SWA patients reaching three bolus doses used FBB event rates. Outcomes were evaluated at trial end and projected annually up to 5 years. Models captured hypoglycemic events, the proportion meeting HbA1c target, and self-measured blood glucose. Event rates and QoL utilities were taken from trial data and published literature. Costs were evaluated from a healthcare-payer perspective, reported in 2013 USD, and discounted (like clinical outcomes) at 3.5% annually. This analysis applies to patients with HbA1c 7.0-9.0% and body mass index Budget impact analysis estimated that, by moving from FBB to SWA, a health plan with 77,000 patients with type 2 diabetes, of whom 7.8% annually intensified to basal-bolus therapy, would save USD 1304 per intensifying patient over the trial period. SWA of bolus insulin should be considered a beneficial and cost-saving alternative to FBB therapy for the intensification of treatment in type 2 diabetes.

Optimized enhancement in helical CT: Experiences with a real-time bolus tracking system in 628 patients

International Nuclear Information System (INIS)

Kirchner, J.; Kickuth, R.; Laufer, U.; Noack, M.; Liermann, D.

2000-01-01

AIMS: Ultrafast detector technology enables bolus-triggered application of contrast media. In a prospective study we investigated the benefit of this new method with the intention of optimizing enhancement during examination of the chest and abdomen. MATERIALS AND METHODS: In total, we examined 548 patients under standardized conditions. All examinations were performed on a Somatom Plus 4 Power CT system (Siemens Corp., Forchheim, Germany) using the CARE-Bolus software. This produces repetitive low-dose test images (e.g. for the lung: 140 kV, 43 mA, TI 0.5 s) and measures the Hounsfield attenuation in a pre-selected region of interest. After exceeding a defined threshold, a diagnostic spiral CT examination was begun automatically. The data obtained from 321 abdominal CT and 179 lung CT examinations were correlated with different parameters such as age, weight and height of the patients and parameters of vascular access. In a group of 80 patients, the injection of contrast medium was stopped after reaching a pre-defined threshold of an increase of 100 HU over the baseline. Then, we assessed the maximal enhancement of liver, pulmonal artery trunk and aortic arch. RESULTS: There was no correlation between bolus geometry and age, body surface or weight. In helical CT of the abdomen the threshold was reached after a mean trigger time of 27 s (range 13-67 s) and only 65 ml (range 41-105 ml) of contrast medium were administered. In helical CT of the lung the threshold was reached after 21 s (range 12-48 s) and the mean amount of administered contrast medium was 48 ml (range 38-71 ml). CONCLUSION: Bolus triggering allows optimized enhancement of the organs and reduces the dose of contrast material required compared with standard administration. Kirchner, J. (2000). Clinical Radiology 55, 368-373

Optimized enhancement in helical CT: experiences with a real-time bolus tracking system in 628 patients.

Science.gov (United States)

Kirchner, J; Kickuth, R; Laufer, U; Noack, M; Liermann, D

2000-05-01

Ultrafast detector technology enables bolus-triggered application of contrast media. In a prospective study we investigated the benefit of this new method with the intention of optimizing enhancement during examination of the chest and abdomen. In total, we examined 548 patients under standardized conditions. All examinations were performed on a Somatom Plus 4 Power CT system (Siemens Corp., Forchheim, Germany) using the CARE-Bolus software. This produces repetitive low-dose test images (e.g. for the lung: 140 kV, 43 mA, TI 0.5 s) and measures the Hounsfield attenuation in a pre-selected region of interest. After exceeding a defined threshold, a diagnostic spiral CT examination was begun automatically. The data obtained from 321 abdominal CT and 179 lung CT examinations were correlated with different parameters such as age, weight and height of the patients and parameters of vascular access. In a group of 80 patients, the injection of contrast medium was stopped after reaching a pre-defined threshold of an increase of 100 HU over the baseline. Then, we assessed the maximal enhancement of liver, pulmonal artery trunk and aortic arch. There was no correlation between bolus geometry and age, body surface or weight. In helical CT of the abdomen the threshold was reached after a mean trigger time of 27 s (range 13-67 s) and only 65 ml (range 41-105 ml) of contrast medium were administered. In helical CT of the lung the threshold was reached after 21 s (range 12-48 s) and the mean amount of administered contrast medium was 48 ml (range 38-71 ml). Bolus triggering allows optimized enhancement of the organs and reduces the dose of contrast material required compared with standard administration. Copyright 2000 The Royal College of Radiologists.

Bolus timing in high-pitch CT angiography of the aorta

International Nuclear Information System (INIS)

Beeres, Martin; Loch, Matthias; Schulz, Boris; Kerl, Matthias; Al-Butmeh, Firas; Bodelle, Boris; Herrmann, Eva; Gruber-Rouh, Tatjana; Lee, Clara; Jacobi, Volkmar; Vogl, Thomas J.

2013-01-01

Objective: To investigate the bolus geometry in high-pitch CT angiography (CTA) of the aorta without ECG synchronisation in comparison to single-source CT. Methods: Overall 160 consecutive patients underwent CTA either in conventional single-source mode with a pitch of 1.2 (group 1), or in dual-source mode with a pitch of 3.0 (groups 2, 3 and 4) using different contrast media timings with bolus triggering at 140 HU (5 s, group 1; 10 s, group 2; 12 s, group 3; 14 s, group 4). Contrast material, saline flush, flow rate and kV/mAs settings were kept equal for optimum comparability. Aortic attenuation was measured along the z-axis of the patient at different anatomic landmarks and subjective image quality was compared. Results: The most homogeneous enhancement of the aorta was reached with a delay of 10 s after reaching the trigger threshold. The imaging length was not significantly different, but the examination time was significantly (p < 0.001) shorter in the high-pitch group (7.7 s vs. 1.7 s for group 1 vs. 2, 3 and 4). Conclusion: In high-pitch CT angiography using a start delay of 10 s after a trigger threshold of 140 HU in the descending aorta is reached, a homogenous contrast along the z-axis is accomplished

Bolus electron conformal therapy for the treatment of recurrent inflammatory breast cancer: a case report

Energy Technology Data Exchange (ETDEWEB)

Kim, Michelle M., E-mail: mmkim@mdanderson.org [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Kudchadker, Rajat J.; Kanke, James E.; Zhang, Sean; Perkins, George H. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States)

2012-07-01

The treatment of locoregionally recurrent breast cancer in patients who have previously undergone radiation therapy is challenging. Special techniques are often required that both eradicate the disease and minimize the risks of retreatment. We report the case of a patient with an early-stage left breast cancer who developed inflammatory-type recurrence requiring re-irradiation of the chest wall using bolus electron conformal therapy with image-guided treatment delivery. The patient was a 51-year-old woman who had undergone lumpectomy, axillary lymph node dissection, and adjuvant whole-breast radiation therapy for a stage I left breast cancer in June 1998. In March 2009, she presented at our institution with biopsy-proven recurrent inflammatory carcinoma and was aggressively treated with multi-agent chemotherapy followed by mastectomy that left a positive surgical margin. Given the patient's prior irradiation and irregular chest wall anatomy, bolus electron conformal therapy was used to treat her chest wall and draining lymphatics while sparing the underlying soft tissue. The patient still had no evidence of disease 21 months after treatment. Our results indicate that bolus electron conformal therapy is an accessible, effective radiation treatment approach for recurrent breast cancer in patients with irregular chest wall anatomy as a result of surgery. This approach may complement standard techniques used to reduce locoregional recurrence in the postmastectomy setting.

Intravenous Bolus versus Continuous Infusion of Famotidine or Ranitidine on 24 H Intragastric Acidity in Fasting Healthy Volunteers

Directory of Open Access Journals (Sweden)

ABR Thomson

1995-01-01

Full Text Available Infusions of H2-receptor antagonists may be clinically indicated to maintain intragastric pH above 4 to reduce acute gastric mucosal lesions or to treat patients with bleeding peptic ulcers. Eight fasting healthy volunteers were randomly assigned to receive ranitidine infusion alone (150 mg/day, ranitidine infusion plus 50 mg bolus injection of ranitidine (total of 200 mg/day, famotidine infusion alone (40 mg/day or famotidine infusion plus 40 mg bolus injection of famotidine (total of 80 mg/day. Gastric fluid contents were aspirated for 24 h and collected as half-hourly samples in which pH measurements were made. Measures analyzed were mean and median pH, percentage pH at or below 3, 4 or 5 for the 24 h period, daytime, evening and nighttime. The data for each of the variables were analyzed as a Latin square crossover design of variance therapy; base pH before treatment administration in each crossover phase was employed as the covariant. Significant differential treatment means were tested by Newman-Keul’s multiple range test at the 5% level of significance. The mean and median evening pH were higher after famotidine than after ranitidine infusion, but all other pH readings were similar when using these doses. The addition of an initial loading bolus of 50 mg ranitidine to the ranitidine infusion did not result in any added differences in pH, whereas the addition of an initial loading bolus of 40 mg famotidine to the famotidine infusion resulted in a higher 24 h median pH, as well as a lower percentage of pH values of 4 or below, 16.6% versus 28.5%, P<0.05. However, the loading doses of ranitidine and famotidine were not equivalent in potency, and studies are needed to compare the potency of equivalent doses of ranitidine and famotidine when given by bolus plus infusion. Also the clinical relevance of these findings needs to be explored further in the type of individuals potentially requiring intravenous H2-receptor antagonists.

SU-E-T-71: A Radiochromic Film Based Quantitative Assessment of Thermoplastic Mask Bolus Effect in Head and Neck IMRT/VMAT

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Kalavagunta, C; Lin, M; Snider, J; Xu, H; Schrum, A; Vadnais, P; Marter, K; Suntharalingam, M; Prado, K [University of Maryland School of Medicine, Baltimore, MD (United States)

2015-06-15

Purpose: To quantify the factors leading to thermoplastic mask bolus-associated-increased skin dose in head and neck IMRT/VMAT using EBT2 film. Methods: EBT2 film placed beneath a dual layer 3-point ORFIT head, neck and shoulder mask was used to test the effect of mask thickness, beam modulation, air gap, and beam obliquity on bolus effect. Mask thickness was varied based on the distribution of 1.6mm Orfilight layer on top of 2 mm Efficast layer. Beam modulation was varied by irradiating the film with an open field (no beam modulation) and a step and shoot field (beam modulation). Air gap between mask and film was varied from 0 to 5mm. Beam obliquity was varied by irradiating the film at gantry angles of 0°, 35°, and 70°.Finally, film strips placed on a Rando phantom under an Orfit mask, in regions of expected high dose, were irradiated using 5 IMRT and 5 VMAT plans with various modulation levels (modulation factor 2 to 5) and the results were compared with those obtained placing OSLDs at the same locations. Results: An 18–34% increase in mask bolus effect was observed for three factors where the effect of beam obliquity ≥ beam modulation > mask thickness. No increase in mask bolus effect was observed for change in air gap. A 6–13% increase in dose due to mask bolus effect was observed on film strips. Conclusion: This work underlines the role of beam obliquity and beam modulation combined with thermoplastic mask thickness in increasing mask bolus-associated skin dose in head and neck IMRT/VMAT. One possible method of dose reduction, based on knowledge gained from this work, is inclusion of skin as an avoidance structure in treatment planning. Another approach is to design a mask with the least amount of thermoplastic material necessary for immobilization.

SU-E-T-71: A Radiochromic Film Based Quantitative Assessment of Thermoplastic Mask Bolus Effect in Head and Neck IMRT/VMAT

International Nuclear Information System (INIS)

Kalavagunta, C; Lin, M; Snider, J; Xu, H; Schrum, A; Vadnais, P; Marter, K; Suntharalingam, M; Prado, K

2015-01-01

Purpose: To quantify the factors leading to thermoplastic mask bolus-associated-increased skin dose in head and neck IMRT/VMAT using EBT2 film. Methods: EBT2 film placed beneath a dual layer 3-point ORFIT head, neck and shoulder mask was used to test the effect of mask thickness, beam modulation, air gap, and beam obliquity on bolus effect. Mask thickness was varied based on the distribution of 1.6mm Orfilight layer on top of 2 mm Efficast layer. Beam modulation was varied by irradiating the film with an open field (no beam modulation) and a step and shoot field (beam modulation). Air gap between mask and film was varied from 0 to 5mm. Beam obliquity was varied by irradiating the film at gantry angles of 0°, 35°, and 70°.Finally, film strips placed on a Rando phantom under an Orfit mask, in regions of expected high dose, were irradiated using 5 IMRT and 5 VMAT plans with various modulation levels (modulation factor 2 to 5) and the results were compared with those obtained placing OSLDs at the same locations. Results: An 18–34% increase in mask bolus effect was observed for three factors where the effect of beam obliquity ≥ beam modulation > mask thickness. No increase in mask bolus effect was observed for change in air gap. A 6–13% increase in dose due to mask bolus effect was observed on film strips. Conclusion: This work underlines the role of beam obliquity and beam modulation combined with thermoplastic mask thickness in increasing mask bolus-associated skin dose in head and neck IMRT/VMAT. One possible method of dose reduction, based on knowledge gained from this work, is inclusion of skin as an avoidance structure in treatment planning. Another approach is to design a mask with the least amount of thermoplastic material necessary for immobilization

Optimization of initial propofol bolus dose for EEG Narcotrend Index-guided transition from sevoflurane induction to intravenous anesthesia in children.

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Dennhardt, Nils; Boethig, Dietmar; Beck, Christiane; Heiderich, Sebastian; Boehne, Martin; Leffler, Andreas; Schultz, Barbara; Sümpelmann, Robert

2017-04-01

Sevoflurane induction followed by intravenous anesthesia is a widely used technique to combine the benefits of an easier and less traumatic venipuncture after sevoflurane inhalation with a recovery with less agitation, nausea, and vomiting after total intravenous anesthesia (TIVA). Combination of two different anesthetics may lead to unwanted burst suppression in the electroencephalogram (EEG) during the transition phase. The objective of this prospective clinical observational study was to identify the optimal initial propofol bolus dose for a smooth transition from sevoflurane induction to TIVA using the EEG Narcotrend Index (NI). Fifty children aged 1-8 years scheduled for elective pediatric surgery were studied. After sevoflurane induction and establishing of an intravenous access, a propofol bolus dose range 0-5 mg·kg -1 was administered at the attending anesthetist's discretion to maintain a NI between 20 and 64, and sevoflurane was stopped. Anesthesia was continued as TIVA with a propofol infusion dose of 15 mg·kg -1 ·h -1 for the first 15 min, followed by stepwise reduction according to McFarlan's pediatric infusion regime, and remifentanil 0.25 μg·kg -1 ·min -1 . Endtidal concentration of sevoflurane, NI, and hemodynamic data were recorded during the whole study period using a standardized case report form. Propofol plasma concentrations were calculated using the paedfusor dataset and a TIVA simulation program. Median endtidal concentration of sevoflurane at the time of administration of the propofol bolus was 5.1 [IQR 4.7-5.9] Vol%. The median propofol bolus dose was 1.2 [IQR 0.9-2.5] mg·kg -1 and median NI thereafter was 33 [IQR 23-40]. Nine children presented with a NI 13-20 and three children with burst suppression in the EEG (NI 0-12); all of them received an initial propofol bolus dose >2 mg·kg -1 . Regression equation demonstrated that NI 20-64 was achieved with a 95% probability when using a propofol bolus dose of 1 mg·kg -1 after

Decoding Biosynthetic Pathways in Plants by Pulse-Chase Strategies Using 13CO2 as a Universal Tracer

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Adelbert Bacher

2016-07-01

Full Text Available 13CO2 pulse-chase experiments monitored by high-resolution NMR spectroscopy and mass spectrometry can provide 13C-isotopologue compositions in biosynthetic products. Experiments with a variety of plant species have documented that the isotopologue profiles generated with 13CO2 pulse-chase labeling are directly comparable to those that can be generated by the application of [U-13C6]glucose to aseptically growing plants. However, the application of the 13CO2 labeling technology is not subject to the experimental limitations that one has to take into account for experiments with [U-13C6]glucose and can be applied to plants growing under physiological conditions, even in the field. In practical terms, the results of biosynthetic studies with 13CO2 consist of the detection of pairs, triples and occasionally quadruples of 13C atoms that have been jointly contributed to the target metabolite, at an abundance that is well above the stochastic occurrence of such multiples. Notably, the connectivities of jointly transferred 13C multiples can have undergone modification by skeletal rearrangements that can be diagnosed from the isotopologue data. As shown by the examples presented in this review article, the approach turns out to be powerful in decoding the carbon topology of even complex biosynthetic pathways.

A Fast CT Reconstruction Scheme for a General Multi-Core PC

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Kai Zeng

2007-01-01

Full Text Available Expensive computational cost is a severe limitation in CT reconstruction for clinical applications that need real-time feedback. A primary example is bolus-chasing computed tomography (CT angiography (BCA that we have been developing for the past several years. To accelerate the reconstruction process using the filtered backprojection (FBP method, specialized hardware or graphics cards can be used. However, specialized hardware is expensive and not flexible. The graphics processing unit (GPU in a current graphic card can only reconstruct images in a reduced precision and is not easy to program. In this paper, an acceleration scheme is proposed based on a multi-core PC. In the proposed scheme, several techniques are integrated, including utilization of geometric symmetry, optimization of data structures, single-instruction multiple-data (SIMD processing, multithreaded computation, and an Intel C++ compilier. Our scheme maintains the original precision and involves no data exchange between the GPU and CPU. The merits of our scheme are demonstrated in numerical experiments against the traditional implementation. Our scheme achieves a speedup of about 40, which can be further improved by several folds using the latest quad-core processors.

A fast CT reconstruction scheme for a general multi-core PC.

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Zeng, Kai; Bai, Erwei; Wang, Ge

2007-01-01

Expensive computational cost is a severe limitation in CT reconstruction for clinical applications that need real-time feedback. A primary example is bolus-chasing computed tomography (CT) angiography (BCA) that we have been developing for the past several years. To accelerate the reconstruction process using the filtered backprojection (FBP) method, specialized hardware or graphics cards can be used. However, specialized hardware is expensive and not flexible. The graphics processing unit (GPU) in a current graphic card can only reconstruct images in a reduced precision and is not easy to program. In this paper, an acceleration scheme is proposed based on a multi-core PC. In the proposed scheme, several techniques are integrated, including utilization of geometric symmetry, optimization of data structures, single-instruction multiple-data (SIMD) processing, multithreaded computation, and an Intel C++ compilier. Our scheme maintains the original precision and involves no data exchange between the GPU and CPU. The merits of our scheme are demonstrated in numerical experiments against the traditional implementation. Our scheme achieves a speedup of about 40, which can be further improved by several folds using the latest quad-core processors.

Study of the usefulness on liver CT using intermittent bolus injection method

International Nuclear Information System (INIS)

Hayashi, Hideo

1990-01-01

Usefulness on the liver CT using intermittent bolus injection method of contrast media (IM-CE) was studied in 108 hepatic space occupying lesions, particularly to analyze hepatocellular carcinoma (HCC). Scans were obtained before, 20∼30 (arterial phase) and 60 seconds (parenchymal phase) after intravenous bolus injection of 65%-diatrizoate (angiografin) or 300 mg I-iopamidol (iopamiron 300), and in case of necessity, added 3∼15 minutes (late phase) after all injections of contrast media. These scans imaging the features of hepatic mass provided us much useful information. Early enhancement of the arterial phase, and early wash out of the parenchymal phase and delayed ring enhancement of the capsule improved the rates of detection to 96%, 60%, and 49% respectively in case of HCC. Especially. at the small HCC (less than 2cm in diameter), these rates were 89%, 50%, and 28% respectively. Combination of these 3 findings suggested the possibility of HCC in comparison with other hepatic mass. The rate of accurate diagnosis of HCC by this IM-CE was 81%. Thus IM-CE CT provides the useful information in diagnosis of hepatic mass and should be considered as the routine examination of hepatic mass. (author)

Lower esophageal mucosal ring: correlation of referred symptoms with radiographic findings using a marshmallow bolus.

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Smith, D F; Ott, D J; Gelfand, D W; Chen, M Y

1998-11-01

The purpose of this investigation was to determine the prevalence of lower esophageal mucosal rings and to correlate the relationship between these mucosal rings and the presence and anatomic level of symptoms evoked using a marshmallow bolus. Our prospective study included 130 patients who underwent barium examination of the esophagus. All patients completed a questionnaire regarding the anatomic location of their symptoms of dysphagia. In addition to a multiphasic examination of the esophagus, all patients also underwent fluoroscopic observation and videotaping while swallowing a marshmallow bolus; any symptoms that were provoked were recorded. Lower esophageal mucosal rings were shown in 26 (20%) of the 130 patients. The diameter of the rings was 9-12 mm in six patients, 13-20 mm in 18 patients, and larger than 20 mm in two patients. In 16 (62%) of the 26 patients, a marshmallow bolus became impacted at the ring; the impaction caused dysphagia in 12 (75%) of the 16 patients. In these 12 patients, dysphagia was referred to the neck in seven, the sternal angle in two, the mid chest in two, and the lower chest in one patient. None of the 12 patients had a pharyngeal or cervical esophageal abnormality that would account for their symptoms. Because proximal referral of symptoms is common in patients with lower esophageal mucosal rings, a thorough radiographic examination of the entire esophagus and esophagogastric region is required regardless of the level of their swallowing complaints.

An additional bolus of rapid-acting insulin to normalise postprandial cardiovascular risk factors following a high-carbohydrate high-fat meal in patients with type 1 diabetes: A randomised controlled trial.

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Campbell, Matthew D; Walker, Mark; Ajjan, Ramzi A; Birch, Karen M; Gonzalez, Javier T; West, Daniel J

2017-07-01

To evaluate an additional rapid-acting insulin bolus on postprandial lipaemia, inflammation and pro-coagulation following high-carbohydrate high-fat feeding in people with type 1 diabetes. A total of 10 males with type 1 diabetes [HbA 1c 52.5 ± 5.9 mmol/mol (7.0% ± 0.5%)] underwent three conditions: (1) a low-fat (LF) meal with normal bolus insulin, (2), a high-fat (HF) meal with normal bolus insulin and (3) a high-fat meal with normal bolus insulin with an additional 30% insulin bolus administered 3-h post-meal (HFA). Meals had identical carbohydrate and protein content and bolus insulin dose determined by carbohydrate-counting. Blood was sampled periodically for 6-h post-meal and analysed for triglyceride, non-esterified-fatty acids, apolipoprotein B48, glucagon, tumour necrosis factor alpha, fibrinogen, human tissue factor activity and plasminogen activator inhibitor-1. Continuous glucose monitoring captured interstitial glucose responses. Triglyceride concentrations following LF remained similar to baseline, whereas triglyceride levels following HF were significantly greater throughout the 6-h observation period. The additional insulin bolus (HFA) normalised triglyceride similarly to low fat 3-6 h following the meal. HF was associated with late postprandial elevations in tumour necrosis factor alpha, whereas LF and HFA was not. Fibrinogen, plasminogen activator inhibitor-1 and tissue factor pathway levels were similar between conditions. Additional bolus insulin 3 h following a high-carbohydrate high-fat meal prevents late rises in postprandial triglycerides and tumour necrosis factor alpha, thus improving cardiovascular risk profile.

Tumor-specific detection of an optically targeted antibody combined with a quencher-conjugated neutravidin "quencher-chaser": a dual "quench and chase" strategy to improve target to nontarget ratios for molecular imaging of cancer.

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Ogawa, Mikako; Kosaka, Nobuyuki; Choyke, Peter L; Kobayashi, Hisataka

2009-01-01

In vivo molecular cancer imaging with monoclonal antibodies has great potential not only for cancer detection, but also for cancer characterization. However, the prolonged retention of intravenously injected antibody in the blood causes low target tumor-to-background ratio (TBR). Avidin has been used as a "chase" to clear the unbound, circulating biotinylated antibody and decrease the background signal. Here, we utilize a combined approach of a fluorescence resonance energy transfer (FRET) quenched antibody with an "avidin chase" to increase TBR. Trastuzumab, a humanized monoclonal antibody against human epidermal growth factor receptor type 2 (HER2), was biotinylated and conjugated with the near-infrared (NIR) fluorophore Alexa680 to synthesize Tra-Alexa680-biotin. Next, the FRET quencher, QSY-21, was conjugated to avidin, neutravidin (nAv), or streptavidin (sAv), thus creating Av-QSY21, nAv-QSY21, or sAv-QSY21 as "chasers". The fluorescence was quenched in vitro by binding Tra-Alexa680-biotin to Av-QSY21, nAv-QSY21, or sAv-QSY21. To evaluate if the injection of quencher-conjugated avidin derivatives can improve target TBR by using a dual "quench and chase" strategy, both target (3T3/HER2+) and nontarget (Balb3T3/ZsGreen) tumor-bearing mice were employed. The "FRET quench" effect induced by all the QSY21 avidin-based conjugates reduced but did not totally eliminate background signal from the blood pool. The addition of nAv-QSY21 administration increased target TBR mainly because of the "chase" effect where unbound conjugated antibody was preferentially cleared to the liver. The relatively slow clearance of unbound nAv-QSY21 leads to further reductions in background signal by leaking out of the vascular space and binding to unbound antibodies in the extravascular space of tumors, resulting in decreased nontarget tumor-to-background ratios but increased target TBR due to the "FRET quench" effect, because target-bound antibodies were internalized and could not bind

Radiation dosimetry for bolus administration of oxygen-15-water

International Nuclear Information System (INIS)

Brihaye, C.; Depresseux, J.C.; Comar, D.

1995-01-01

The authors describe the development of a biokinetic model which permits an estimation of organ activities and the dosimetry of a bolus of 15 O-water. The aim of this study was to estimate time-activity functions and deduce the cumulated activities in different organs so that the radiation absorbed dose values can be estimated. The model used includes the right heart chambers, lungs, left heart chambers, brain, liver, kidneys, muscles, gasrointestinal tract and the remainder of the body. Activity in an organ will decay by physical decay with the decay constant, γ, and can diffuse in the organ. An exception is the heart, where blood is ejected from the heart chambers. Depending on the location of the organ in relation to the blood sampling point, organ activities can be calculated by convolution or deconvolution. The radiation absorbed dose values were estimated and an effective dose equivalent H E of 1.16 μSv/MBq (4.32 mrem/mCi) as well as an effective dose E of 1.15 μSv/MBq (4.25 mrem/mCi) were calculated. The cumulated activities in select organs measured by PET gave good agreement with the values calculated by this model. The values of effective dose equivalent and effective dose for bolus administration of 15 O-water calculated from the absorbed doses estimated by the proposed kinetic model are almost three times higher than those previously published. A total of 8700 MBq (235 mCi) of 15 O-water can be administered if an effective dose of 10 mSv (1 rem) is accepted. 32 refs., 5 figs., 2 tabs

Pathological bolus exposure may define gastro-esophageal reflux better than pathological acid exposure in patients with globus.

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Sinn, Dong Hyun; Kim, Beom Jin; Son, Hee Jung; Kim, Jae J; Rhee, Jong Chul; Rhee, Poong-Lyul

2012-01-01

Conventionally, pathological acid exposure (PAE), defined by acid reflux only, is used to identify gastro-esophageal reflux disease (GERD). However, weak acid reflux or non-acid reflux also induces reflux symptoms. Defining abnormal reflux based on all reflux episodes may better identify GERD and would be more useful among patients with atypical GERD symptoms, such as globus. Impedance-pHmetry results of 31 globus patients, off acid suppressants, were analysed. A median of 24 episodes of reflux were observed. Of the reflux episodes, 54% were non-acid reflux and 50% reached the proximal extent. PAE was observed in 6 patients (19%). For 5 patients (16%) without PAE, there was evidence of increased bolus exposure compared to normal controls (an intraesophageal bolus exposure for more than 1.4% of the recording time, defined as pathological bolus exposure, PBE). When GERD was defined by PAE or esophagitis, the prevalence of GERD was 29%. When GERD was defined by PBE, PAE or esophagitis, the prevalence was 42%. PBE identified 13% of the patients who otherwise would have been missed. A significant proportion of patients without PAE had evidence of PBE. PBE may be a more useful definition for identifying patients with abnormal increase in reflux in patients with globus. Further studies are warranted.

Real-time measurements of nitrogen oxide emissions from in-use New York City transit buses using a chase vehicle.

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Shorter, Joanne H; Herndon, Scott; Zahniser, Mark S; Nelson, David D; Wormhoudt, Joda; Demerjian, Kenneth L; Kolb, Charles E

2005-10-15

New diesel engine technologies and alternative fuel engines are being introduced into fleets of mass transit buses to try to meet stricter emission regulations of nitrogen oxides and particulates: Real-time instruments including an Aerodyne Research tunable infrared laser differential absorption spectrometer (TILDAS) were deployed in a mobile laboratory to assess the impact of the implementation of the new technologies on nitrogen oxide emissions in real world driving conditions. Using a "chase" vehicle sampling strategy, the mobile laboratory followed target vehicles, repeatedly sampling their exhaust. Nitrogen oxides from approximately 170 in-use New York City mass transit buses were sampled during the field campaigns. Emissions from conventional diesel buses, diesel buses with continuously regenerating technology (CRT), diesel hybrid electric buses, and compressed natural gas (CNG) buses were compared. The chase vehicle sampling method yields real world emissions that can be included in more realistic emission inventories. The NO, emissions from the diesel and CNG buses were comparable. The hybrid electric buses had approximately one-half the NOx emissions. In CRT diesels, NO2 accounts for about one-third of the NOx emitted in the exhaust, while for non-CRT buses the NO2 fraction is less than 10%.

Direct bolus imaging of cervical blood vessels by means of MRI

International Nuclear Information System (INIS)

Satoh, Toshihiko; Fujioka, Mutsuhisa; Watari, Tsutomu; Nishimura, Gen; Matsumoto, Toshihiko; Washiya, Sumio; Inoue, Kiyoshi; Horita, Masatoshi; Shimizu, Kohji.

1991-01-01

Direct bolus imaging (DBI) is one of the non-invasive method for flow measurements which is based on the bolus tracking technique. DBI permits the direct visualization of flow velocity profiles and vessel band width. We performed screening for cervical vessel disease in patients with vertigo by means of DBI. MR system used here was 0.5 T superconducting imager-SMT-50A (Shimazu Co. Ltd). Pulse sequence parameters were TR= 60 ms, TE= 50 ms, NEX= 1, acquisition matrix; 128 x 256, slice thickness= 5 mm, with cardiac gating. Pulse sequence employed a slice selective RF pulse at the level of C5 vertebral body to tag a disk of fluid perpendicular to the direction of flow, followed by a gradient reforcussed echo. We evaluated each peak high and band width of the common-carotid arteries and the vertebral arteries. Seventy nine of 83 cases had optimal examinations. Abnormal findings of DBI were seen in 15 of 79 cases, (including 2 of subclavian steal syndrome, 1 of carotid obstruction, 5 of vertebral obstruction, 1 of basilar artery obstruction, and 6 of hypoplasia of vertebral artery). The abnormal findings of DBI were well correlated with those of angiographic examinations. We concluded that DBI was suitable to the screening for cervical vessel diseases in patients with vertigo, and should be added to the routine MR studies. (author)

Impaired bolus clearance in combined high-resolution esophageal manometry and impedance measurement helps to differentiate between esophagogastric junction outflow obstruction and achalasia.

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Zizer, Eugen; Seufferlein, Thomas; Hänle, Mark Martin

2017-02-01

Introduction and aims  High-resolution esophageal manometry (HRM) has improved the diagnostic work-up of esophageal motility disorders. Simultaneous evaluation of bolus clearance delivers useful information about the function of tubular esophagus. We assessed bolus clearance in a combined HRM-impedance examination for esophagogastric junction outflow obstruction (EGJOO) in comparison to achalasia patients. The collected data were assessed in a retrospective analysis. Patients and methods  After gastroscopy excluded a mechanical esophageal or gastric obstruction, 142 consecutive patients underwent combined HRM-impedance examination. The assessment and interpretation of the manometry results were done according to the Chicago Classification of esophageal motility disorders v3.0. After classifying the motility disorder, the evaluation of bolus clearance was done according to published studies. Results  All patients with achalasia (n = 24) showed a significantly impaired bolus clearance (achalasia cases. This might be helpful as an additional tool to differentiate between achalasia and EGJOO patients. Furthermore, the role of the combined impedance-HRM investigation for early diagnosis of achalasia in "pre-achalasia" condition or in evaluation of potential progress of EGJOO to achalasia should be evaluated in a prospective study. © Georg Thieme Verlag KG Stuttgart · New York.

SU-E-T-356: Accuracy of Eclipse Electron Macro Monte Carlo Dose Algorithm for Use in Bolus Electron Conformal Therapy

International Nuclear Information System (INIS)

Carver, R; Popple, R; Benhabib, S; Antolak, J; Sprunger, C; Hogstrom, K

2014-01-01

Purpose: To evaluate the accuracy of electron dose distribution calculated by the Varian Eclipse electron Monte Carlo (eMC) algorithm for use with recent commercially available bolus electron conformal therapy (ECT). Methods: eMC-calculated electron dose distributions for bolus ECT have been compared to those previously measured for cylindrical phantoms (retromolar trigone and nose), whose axial cross sections were based on the mid-PTV CT anatomy for each site. The phantoms consisted of SR4 muscle substitute, SR4 bone substitute, and air. The bolus ECT treatment plans were imported into the Eclipse treatment planning system and calculated using the maximum allowable histories (2×10 9 ), resulting in a statistical error of <0.2%. Smoothing was not used for these calculations. Differences between eMC-calculated and measured dose distributions were evaluated in terms of absolute dose difference as well as distance to agreement (DTA). Results: Results from the eMC for the retromolar trigone phantom showed 89% (41/46) of dose points within 3% dose difference or 3 mm DTA. There was an average dose difference of −0.12% with a standard deviation of 2.56%. Results for the nose phantom showed 95% (54/57) of dose points within 3% dose difference or 3 mm DTA. There was an average dose difference of 1.12% with a standard deviation of 3.03%. Dose calculation times for the retromolar trigone and nose treatment plans were 15 min and 22 min, respectively, using 16 processors (Intel Xeon E5-2690, 2.9 GHz) on a Varian Eclipse framework agent server (FAS). Results of this study were consistent with those previously reported for accuracy of the eMC electron dose algorithm and for the .decimal, Inc. pencil beam redefinition algorithm used to plan the bolus. Conclusion: These results show that the accuracy of the Eclipse eMC algorithm is suitable for clinical implementation of bolus ECT

SU-E-T-356: Accuracy of Eclipse Electron Macro Monte Carlo Dose Algorithm for Use in Bolus Electron Conformal Therapy

Energy Technology Data Exchange (ETDEWEB)

Carver, R [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States); Popple, R; Benhabib, S [UniversityAlabama Birmingham, Birmingham, AL (United Kingdom); Antolak, J [Mayo Clinic, Rochester, MN (United States); Sprunger, C [Louisiana State University, Baton Rouge, LA (United States); Hogstrom, K [Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States); Louisiana State University, Baton Rouge, LA (United States)

2014-06-01

Purpose: To evaluate the accuracy of electron dose distribution calculated by the Varian Eclipse electron Monte Carlo (eMC) algorithm for use with recent commercially available bolus electron conformal therapy (ECT). Methods: eMC-calculated electron dose distributions for bolus ECT have been compared to those previously measured for cylindrical phantoms (retromolar trigone and nose), whose axial cross sections were based on the mid-PTV CT anatomy for each site. The phantoms consisted of SR4 muscle substitute, SR4 bone substitute, and air. The bolus ECT treatment plans were imported into the Eclipse treatment planning system and calculated using the maximum allowable histories (2×10{sup 9}), resulting in a statistical error of <0.2%. Smoothing was not used for these calculations. Differences between eMC-calculated and measured dose distributions were evaluated in terms of absolute dose difference as well as distance to agreement (DTA). Results: Results from the eMC for the retromolar trigone phantom showed 89% (41/46) of dose points within 3% dose difference or 3 mm DTA. There was an average dose difference of −0.12% with a standard deviation of 2.56%. Results for the nose phantom showed 95% (54/57) of dose points within 3% dose difference or 3 mm DTA. There was an average dose difference of 1.12% with a standard deviation of 3.03%. Dose calculation times for the retromolar trigone and nose treatment plans were 15 min and 22 min, respectively, using 16 processors (Intel Xeon E5-2690, 2.9 GHz) on a Varian Eclipse framework agent server (FAS). Results of this study were consistent with those previously reported for accuracy of the eMC electron dose algorithm and for the .decimal, Inc. pencil beam redefinition algorithm used to plan the bolus. Conclusion: These results show that the accuracy of the Eclipse eMC algorithm is suitable for clinical implementation of bolus ECT.

Reducing the radiation dose to the eye lens region during CT brain examination: the potential beneficial effect of the combined use of bolus and a bismuth shield

International Nuclear Information System (INIS)

Lai, C.W.K.; Chan, T.P.; Cheung, H.Y.; Wong, T.H.

2015-01-01

Objective: Computed Tomography (CT) is the leading contributor to medical exposure to ionizing radiation. Although the use of CT brain scans for patients with head injuries and convulsions has shown a tremendous growth, it has raised substantial concerns in the general public because of the risk of radiation-induced cataracts: the current available strategies to reduce the radiation dose to the eye lens region are limited. Therefore, the present research project was initiated with the aim of evaluating the potential benefit of the combined use of bolus and a bismuth shield on reducing the radiation dose to the eye lens region during CT brain examination. Materials and methods: We conducted a series of phantom studies to measure the entrance surface dose (ESD) that is delivered to the eye lens region during CT brain examination under the effect of different scanning and shielding setups. Results: Our results indicated, during CT brain examination: (1) a drastic reduction of 92.5% in the ESD to the eye lens region was found when the CT gantry was tilted from 0 deg. (overall ESD = 30.7 mGy) to 30 deg. cranially (overall ESD = 2.4 mGy), and (2) when the CT gantry was positioned at 0 deg. (the common practice in the clinical setting), the setups with the application of a) a bismuth shield, b) a bismuth shield with a face shield (air gap), c) a bismuth shield with bolus, and d) a bismuth shield with bolus and an air gap can result in an acceptable level of image quality with a smaller overall ESD delivered to the eye lens region (overall ESD = 23.2 mGy, 24 mGy, 21 mGy and 19.9 mGy, respectively) than the setup without the bismuth shield applied (overall ESD = 30.7 mGy). Conclusion: When the primary beam scanning through the eye lens region is unavoidable during CT brain examination, the combined use of a bismuth shield with bolus and a face shield is an easy-to-use and inexpensive shielding setup to reduce the radiation dose delivered to the eye lens region while

Douglas Lowy and Nirali Shah discuss advancements in cancer treatment at the second annual Chasing Cancer Summit | Center for Cancer Research

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On Monday, September 18, 2017, the second annual Chasing Cancer Summit was held at the Washington Post headquarters in downtown Washington, D.C. The live event brought together a group of experts, including CCR’s Douglas Lowy, M.D., and Nirali Shah, M.D., for discussions on the latest developments in cancer detection and treatment.  Read more...

Doxorubicin: Comparison between 3-h continuous and bolus intravenous administration paradigms on cardio-renal axis, mitochondrial sphingolipids and pathology

International Nuclear Information System (INIS)

Kamendi, Harriet; Zhou, Ying; Crosby, Meredith; Keirstead, Natalie; Snow, Debra; Bentley, Patricia; Patel, Nilaben; Barthlow, Herbert; Luo, Wenli; Dragan, Yvonne; Bialecki, Russell

2015-01-01

Doxorubicin (DOX) is a potent and effective broad-spectrum anthracycline antitumor agent, but its clinical usefulness is restricted by cardiotoxicity. This study compared pharmacokinetic, functional, structural and biochemical effects of single dose DOX bolus or 3-h continuous iv infusion (3-h iv) in the Han–Wistar rat to characterize possible treatment-related differences in drug safety over a 72 h observation period. Both DOX dosing paradigms significantly altered blood pressure, core body temperature and QA interval (indirect measure of cardiac contractility); however, there was no recovery observed in the bolus iv treatment group. Following the 3-h iv treatment, blood pressures and QA interval normalized by 36 h then rose above baseline levels over 72 h. Both treatments induced biphasic changes in heart rate with initial increases followed by sustained decreases. Cardiac injury biomarkers in plasma were elevated only in the bolus iv treatment group. Tissue cardiac injury biomarkers, cardiac mitochondrial complexes I, III and V and cardiac mitochondrial sphingolipids were decreased only in the bolus iv treatment group. Results indicate that each DOX dosing paradigm deregulates sinus rhythm. However, slowing the rate of infusion allows for functional compensation of blood pressure and may decrease the likelihood of cardiac myocyte necrosis via a mechanism associated with reduced mitochondrial damage. - Highlights: • Despite damaging cardiomyocytes, continuous iv doxorubicin improves cardiovascular outcomes. • This study supports administration of doxorubicin via slow continuous iv infusion limits acute cardio-toxicity. • This study supports use of metabolomic-derived lipid biomarkers for improved quantification of cardiovascular risk. • This study supports systems-based physiological approach to generate a data that can greatly inform risk assessments.

Doxorubicin: Comparison between 3-h continuous and bolus intravenous administration paradigms on cardio-renal axis, mitochondrial sphingolipids and pathology

Energy Technology Data Exchange (ETDEWEB)

Kamendi, Harriet, E-mail: harriet_kamendi@kandih.com [Drug Safety and Metabolism, AstraZeneca, Waltham, MA 02451 (United States); Zhou, Ying, E-mail: yingzhou526@gmail.com [Oncology Innovative Medicines and Early Development, AstraZeneca, Waltham, MA 02451 (United States); Crosby, Meredith, E-mail: Meredith.crosby@astrazeneca.com [Drug Safety and Metabolism, AstraZeneca, Waltham, MA 02451 (United States); Keirstead, Natalie, E-mail: Nkeirstead@alnylam.com [Drug Safety and Metabolism, AstraZeneca, Waltham, MA 02451 (United States); Snow, Debra, E-mail: Debra.snow@astrazeneca.com [Drug Safety and Metabolism, AstraZeneca, Waltham, MA 02451 (United States); Bentley, Patricia, E-mail: patricia.bentley@abbvie.com [Drug Safety and Metabolism, AstraZeneca, Waltham, MA 02451 (United States); Patel, Nilaben, E-mail: patelnilaben@yahoo.com [Drug Safety and Metabolism, AstraZeneca, Waltham, MA 02451 (United States); Barthlow, Herbert, E-mail: Herbert.barthlow@astrazeneca.com [Drug Safety and Metabolism, AstraZeneca, Waltham, MA 02451 (United States); Luo, Wenli, E-mail: Wenli.luo@astrazeneca.com [Discovery Sciences, Innovative Medicines, AstraZeneca, Waltham, MA 02451 (United States); Dragan, Yvonne, E-mail: Yvonne.P.Dragan@takeda.com [Drug Safety and Metabolism, AstraZeneca, Waltham, MA 02451 (United States); Bialecki, Russell, E-mail: russell.bialecki@astrazeneca.com [Drug Safety and Metabolism, AstraZeneca, Waltham, MA 02451 (United States)

2015-12-15

Doxorubicin (DOX) is a potent and effective broad-spectrum anthracycline antitumor agent, but its clinical usefulness is restricted by cardiotoxicity. This study compared pharmacokinetic, functional, structural and biochemical effects of single dose DOX bolus or 3-h continuous iv infusion (3-h iv) in the Han–Wistar rat to characterize possible treatment-related differences in drug safety over a 72 h observation period. Both DOX dosing paradigms significantly altered blood pressure, core body temperature and QA interval (indirect measure of cardiac contractility); however, there was no recovery observed in the bolus iv treatment group. Following the 3-h iv treatment, blood pressures and QA interval normalized by 36 h then rose above baseline levels over 72 h. Both treatments induced biphasic changes in heart rate with initial increases followed by sustained decreases. Cardiac injury biomarkers in plasma were elevated only in the bolus iv treatment group. Tissue cardiac injury biomarkers, cardiac mitochondrial complexes I, III and V and cardiac mitochondrial sphingolipids were decreased only in the bolus iv treatment group. Results indicate that each DOX dosing paradigm deregulates sinus rhythm. However, slowing the rate of infusion allows for functional compensation of blood pressure and may decrease the likelihood of cardiac myocyte necrosis via a mechanism associated with reduced mitochondrial damage. - Highlights: • Despite damaging cardiomyocytes, continuous iv doxorubicin improves cardiovascular outcomes. • This study supports administration of doxorubicin via slow continuous iv infusion limits acute cardio-toxicity. • This study supports use of metabolomic-derived lipid biomarkers for improved quantification of cardiovascular risk. • This study supports systems-based physiological approach to generate a data that can greatly inform risk assessments.

Patterns of Light Chasing the Spectrum from Aristotle to LEDs

CERN Document Server

Beeson, Steven

2008-01-01

Light is all around us – even when we do not see it. Our eyes do not detect the higher energy and shorter-than-visible-wavelength ultraviolet radiation, yet we know it is there from the sunburn we receive in Arizona. We know that window glass can block ultraviolet rays so we do not get a burn while driving with the windows rolled up. Our eyes do not detect the low-energy, long-wavelength infrared (IR) radiation but we know it exists from discussions of war applications and televised images of guided weapons targets. We also know about radio waves from the little boxes that talk to us and x-rays from the dentist's office. Patterns of Light, Chasing the Spectrum from Aristotle to LEDs, written by Steve Beeson and Jim Mayer starts with the visible – the straight path of light. It continues with chapters detailing reflection (mirrors, storefront windows) and refraction (eyeglasses, binoculars). Color is then introduced with the query "Why is the sky blue?" After answering that and other similar questions ("Wh...

Chasing Science at Sea: Racing Hurricanes, Stalking Sharks, and Living Undersea With Ocean Experts

Science.gov (United States)

Lee, Cindy

2008-12-01

Ellen Prager's new book, Chasing Science at Sea, is a personal account of why fieldwork is so important in many areas of ocean science, and how exciting that fieldwork can be. Prager has interwoven her own story of studying carbonates at the interface between biology and geology with stories from friends and colleagues. Storm stories and up-close-and-personal encounters with ocean creatures such as reef squid, marine iguanas, and whales abound. Throughout the book, she emphasizes the idea that the combination of observations and serendipity plays a critical role in science, and she gives examples of where this combination has led to especially important discoveries (e.g., that of hydrothermal vent organisms).

Chasing The 'Like': Adolescent Use Of Social Networking Sites In Australia.

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la Sala, Louise; Skues, Jason; Wise, Lisa; Theiler, Stephen

2015-01-01

The current study investigated how adolescents behave on Social Networking Sites (SNSs) and how they interpret the feedback they receive online from others. Thirty-four Australian adolescents (26 girls, 8 boys) aged 13 to 17 years participated in the study. Five semi-structured focus groups (3 mixed groups, 2 all-girl groups) were conducted to explore how adolescents perceive their own and others' SNS behaviours, the motivation underlying these behaviours, and the expected outcomes related to particular behaviours. Teenagers reported that they spend a good deal of time planning their SNS posts, felt that the information they posted was a true reflection of them as a person, and thus interpreted feedback ("likes") as measuring their self-worth. In contrast, some teenagers were perceived as "chasing the like" for status and popularity while not caring about how accurately their posts represented them as a person. A potential gender bias in these findings is discussed.

ECMO: Improving our Results by Chasing the Rabbits

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Luiz Fernando Canêo

2015-12-01

Full Text Available ABSTRACT As Marcelo Giugale published in the Financial Times, Latin America, on the whole, has not excelled at innovation - doing the same things in a new and better way or at doing new things. It has been slow to acquire, adopt and adapt technologies by this time available in other places[1]. Although extracorporeal membrane oxygenation (ECMO is not a new technology, its use in Latin America is not widespread as needed. Furthermore, we still have a number centers doing ECMO, not reporting their cases, lacking a structured training program and not registered with the extracorporeal life support organization (ELSO. With this scenario, and accepting that ECMO is the first step in any circulatory support program, it is difficult to anticipate the incorporation of new and more complex devices as the technologically advanced world is currently doing. However, the good news is that with the support of experts from USA, Europe and Canada the results in Latin America ELSO'S centers are improving by following its guidelines for training, and using a standard educational process. There is no doubt that we can learn a great deal from the high velocity organizations - the rabbits - whom everyone chases but never catches, that manage to stay ahead because of their endurance, responsiveness, and their velocity in self-correction[2].

Resting myocardial blood flow quantification using contrast-enhanced magnetic resonance imaging in the presence of stenosis: A computational fluid dynamics study

Energy Technology Data Exchange (ETDEWEB)

Sommer, Karsten, E-mail: sommerk@uni-mainz.de, E-mail: Schreiber-L@ukw.de [Section of Medical Physics, Department of Radiology, Johannes Gutenberg University Medical Center, Mainz 55131, Germany and Max Planck Graduate Center with the Johannes Gutenberg University Mainz, Mainz 55128 (Germany); Bernat, Dominik; Schmidt, Regine; Breit, Hanns-Christian [Section of Medical Physics, Department of Radiology, Johannes Gutenberg University Medical Center, Mainz 55131 (Germany); Schreiber, Laura M., E-mail: sommerk@uni-mainz.de, E-mail: Schreiber-L@ukw.de [Comprehensive Heart Failure Center, Department of Cardiovascular Imaging, Würzburg University Hospital, Würzburg 97078 (Germany)

2015-07-15

Purpose: The extent to which atherosclerotic plaques affect contrast agent (CA) transport in the coronary arteries and, hence, quantification of myocardial blood flow (MBF) using magnetic resonance imaging (MRI) is unclear. The purpose of this work was to evaluate the influence of plaque induced stenosis both on CA transport and on the accuracy of MBF quantification. Methods: Computational fluid dynamics simulations in a high-detailed realistic vascular model were employed to investigate CA bolus transport in the coronary arteries. The impact of atherosclerosis was analyzed by inserting various medium- to high-grade stenoses in the vascular model. The influence of stenosis morphology was examined by varying the stenosis shapes but keeping the area reduction constant. Errors due to CA bolus transport were analyzed using the tracer-kinetic model MMID4. Results: Dispersion of the CA bolus was found in all models and for all outlets, but with a varying magnitude. The impact of stenosis was complex: while high-grade stenoses amplified dispersion, mild stenoses reduced the effect. Morphology was found to have a marked influence on dispersion for a small number of outlets in the post-stenotic region. Despite this marked influence on the concentration–time curves, MBF errors were less affected by stenosis. In total, MBF was underestimated by −7.9% to −44.9%. Conclusions: The presented results reveal that local hemodynamics in the coronary vasculature appears to have a direct impact on CA bolus dispersion. Inclusion of atherosclerotic plaques resulted in a complex alteration of this effect, with both degree of area reduction and stenosis morphology affecting the amount of dispersion. This strong influence of vascular transport effects impairs the accuracy of MRI-based MBF quantification techniques and, potentially, other bolus-based perfusion measurement techniques like computed tomography perfusion imaging.

One year results of preoperative single bolus ATG-Fresenius induction therapy in sensitized renal transplant recipients.

Science.gov (United States)

Wang, D; Chen, J H; Wu, W Z; Yang, S L; Wu, G J; Wang, H; Tan, J M

2007-01-01

Sensitization in kidney transplantation is associated with more acute rejections, inferior graft survival, and an increase in delayed graft function. This study was designed to evaluate the efficacy and safety of preoperative single bolus antithymocyte globulin (ATG) induction therapy in sensitized renal transplant recipients. Fifty-six cadaveric donor kidney transplant recipients were divided into two groups: Group I (nonsensitized group, n = 30) and group II (sensitized group, PRA>10%, n = 26). ATG was given as a single preoperative bolus induction therapy to group II (ATG IV; 9 mg/kg). The group I patients were treated with mycophenolate mofetil preoperatively as induction therapy. The basic immunosuppressive regimen included tacrolimus (FK-506) or cyclosporine, mycophenolate mofetil, and prednisolone. After hospital discharge, patients were followed on a routine outpatient basis for 12 months. Acute rejection episodes (ARE) occurred in 20% (6/30) of group I and 15.38% (4/26) of group II patients (P = NS). Infections occurred in eight patients (26.7%) as 11 episodes (36.7%), averaging 1.4 episodes per infected patient in group 1, and 6 patients (23.1%) for a total of 10 episodes (38.5%), averaging 1.7 episodes per infected patient, in group II (P = NS). Occurrence of side effects and hospital stay were almost comparable in the two groups. No delayed graft function was observed in either group. The 12-month actuarial patient and graft survival were 100% in Group I and II. A preoperative single bolus ATG induction therapy was an effective and safe therapeutic measure, yielding an acceptable acute rejection rate in presensitized renal transplant recipients.

Ocular dynamics of Garcinia cola (Heckel on healthy volunteers following bolus ingestion

Directory of Open Access Journals (Sweden)

S. A. Igwe

2007-12-01

Full Text Available Garcinia cola Heckel, an angiospermae belonging to the  family Guttiferae, is known in commerce as bitter cola. It is a plant found in the West African subregion, mostly in moist conditions, and often in association with Cola acuminata. The seeds are highly valued ingredients in African ethonomedicine. The seeds have several social uses and applications in folk medicine. These seeds are ordinarily chewed by the local people without prescription or restriction. In an in vivo case control study, the effects of Garcinia cola on some visual functions: pupil diameter, near point of convergence (NPC, amplitude of accommodation (AA, intraocular pressure (IOP, visual acuity (VA and habitual phoria; following bolus ingestion of 20 g was undertaken using healthy visually active volunteers. Results showed that bolus ingestion of Garcinia cola constricted the pupil by 68%, reduced the NPC by 28%, increased the AA by 17.8% at peak effect and decreased the intraocular pressure by 31% without affecting the distance and near VA. The lateral phoria at far and near tended towards esophoria. Possibly the miotic effect and reduction in IOP could be of benefit to patients with raised IOP where conventional drugs may not be effective. Also it is possible that the effects on phoria could be exploited in oculomotor function in combination with visual training.

Evaluation of a bolus/infusion protocol for 11C-ABP688, a PET tracer for mGluR5

International Nuclear Information System (INIS)

Burger, Cyrill; Deschwanden, Alexandra; Ametamey, Simon; Johayem, Anass; Mancosu, Bruno; Wyss, Matthias; Hasler, Gregor; Buck, Alfred

2010-01-01

11 C-ABP-688 is a selective tracer for the mGluR5 receptor. Its kinetics is fast and thus favourable for an equilibrium approach to determine receptor-related parameters. The purpose of this study was to test the hypothesis that the pattern of the 11 C-ABP688 uptake using a bolus-plus-infusion (B/I) protocol at early time points corresponds to the perfusion and at a later time point to the total distribution volume. Methods: A bolus and a B/I study (1 h each) was performed in five healthy male volunteers. With the B/I protocol, early and late scans were normalized to gray matter, cerebellum and white matter. The same normalization was done on the maps of the total distribution volume (Vt) and K 1 which were calculated in the study with bolus only injection and the Logan method (Vt) and a two-tissue compartment model (K 1 ). Results: There was an excellent correlation close to the identity line between the pattern of the late uptake in the B/I study and Vt of the bolus-only study for all three normalizations. The pattern of the early uptake in the B/I study correlated well with the K 1 maps, but only when normalized to gray matter and cerebellum, not to white matter. Conclusion: It is demonstrated that with a B/I protocol the 11 C-ABP688 distribution in late scans reflects the pattern of the total distribution volume and is therefore a measure for the density pattern of mGluR5. The early scans following injection are related to blood flow, although not in a fully quantitative manner. The advantage of the B/I protocol is that no arterial blood sampling is required, which is advantageous in clinical studies.

Contrast agent bolus tracking with a fixed threshold or a manual fast start for coronary CT angiography

Energy Technology Data Exchange (ETDEWEB)

Stenzel, Fabian; Rief, Matthias; Zimmermann, Elke; Greupner, Johannes; Richter, Felicitas; Dewey, Marc [Charite - Universitaetsmedizin Berlin, Department of Radiology, Berlin (Germany)

2014-06-15

Comparison of bolus tracking with a fixed threshold versus a manual fast start for coronary CT angiography. We retrospectively analysed 320-row coronary CT angiography of 50 patients with suspected or known coronary artery disease. Twenty-five examinations were initiated by a bolus tracking method (group 1), 25 examinations with a manual fast surestart (group 2). Mean attenuation values in the ascending aorta were 519 ± 111 Hounsfield units (HU) in group 1 and 476 ± 65 HU in group 2 (p = 0.10). Assessable vessel lengths were 171 ± 44 mm vs 172 ± 29 mm for the right coronary artery (p = 0.91), 11 ± 4 mm vs 12 ± 4 mm for the left main (p = 0.9), 163 ± 28 mm vs 151 ± 26 mm for the left anterior descending coronary artery (p = 0.11) and 125 ± 41 mm vs 110 ± 37 mm for the left circumflex coronary artery (p = 0.18). Image quality for all coronary arteries was not significantly different between the groups (p > 0.41). The attenuation ratio between the left and right ventricle was 2.8 ± 0.7 vs 3.6 ± 1.0 (p = 0.003). Significantly less contrast agent was used in group 2 (64 ± 6 ml vs 80 ± 0 ml; p < 0.001). Bolus tracking with a fixed threshold and with a manual fast start are both suitable methods; the fast start allowed a reduction of contrast agent volumes. (orig.)

Myocardial oxygen extraction fraction measured using bolus inhalation of 15O-oxygen gas and dynamic PET

NARCIS (Netherlands)

Lubberink, Mark; Wong, YY; Raijmakers, P. G.; Huisman, Marc C.; Schuit, Robert C.; Luurtsema, Geert; Boellaard, Ronald; Knaapen, P; Vonk-Noordegraaf, Anton; Lammertsma, Adriaan A.

Abstract The aim of this study was to determine the accuracy of oxygen extraction fraction (OEF) measurements using a dynamic scan protocol after bolus inhalation of 15O2. The method of analysis was optimized by investigating potential reuse of myocardial blood flow (MBF), perfusable tissue

Behaviorism Makes Its Debut: A Review of Lattal and Chase's Behavior Theory and Philosophy

Science.gov (United States)

Zuriff, G.E

2005-01-01

Behavior Theory and Philosophy, masterfully edited by Lattal and Chase, is a collection of 21 papers by major behaviorists, presented and discussed at a conference on the intersection of philosophy and behavior analysis held at West Virginia University in 2000. The chapters in Part I are devoted to philosophy of science (causality, constructs, theory, explanation, reductionism) and the relations among behavior analysis and several contemporary philosophical movements (humanism, empiricism, pragmatism, selectionism, analytic philosophy). Part II examines behavior-analytic interpretations of mentalistic concepts (intention, imagination, ethics, cognition). Part III presents extensions and applications of basic research in behavior analysis (verbal behavior, creativity, development, education, disability, and corporate culture). The publication of this book signals that behaviorism has developed mature philosophical foundations.

The measurement of fringing fields in a radio-frequency hyperthermia array with emphasis on bolus size

NARCIS (Netherlands)

Wiersma, J.; van Dijk, J. D.; Sijbrands, J.; Schneider, C. J.

1998-01-01

The limited aperture size through which the em-field of the applicator is emanated and the constraining of this em-field near the bolus' edge is related to the appearance of superficial 'hot spot' phenomena in radiative hyperthermia. Regarding systems based on the concept of the annular phased array

Non-invasive determination of pulmonary hypertension with dynamic contrast-enhanced computed tomography: a pilot study

International Nuclear Information System (INIS)

Pienn, Michael; Balint, Zoltan; Kovacs, Gabor; Tscherner, Maria; Olschewski, Horst; Avian, Alexander; Johnson, Thorsten R.; Kullnig, Peter; Stollberger, Rudolf; Olschewski, Andrea

2014-01-01

In this pilot study we explored whether contrast-material bolus propagation time and speed in the pulmonary arteries (PAs) determined by dynamic contrast-enhanced computed tomography (DCE-CT) can distinguish between patients with and without pulmonary hypertension (PH). Twenty-three patients (18 with and 5 without PH) were examined with a DCE-CT sequence following their diagnostic or follow-up right-sided heart catheterisation (RHC). X-ray attenuation over time curves were recorded for regions of interest in the main, right and left PA and fitted with a spline fit. Contrast material bolus propagation speeds and time differences between the peak concentrations were compared with haemodynamic parameters from RHC. Bolus speed correlated (ρ = -0.55) with mean pulmonary arterial pressure (mPAP) and showed a good discriminative power between patients with and without PH (cut-off speed 317 mm/s; sensitivity 100 %/specificity 100 %). Additionally, time differences between peaks correlated with mPAP (ρ = 0.64 and 0.49 for right and left PA, respectively) and discrimination was achieved with sensitivity 100 %/specificity 100 % (cut-off time 0.15 s) and sensitivity 93 %/specificity 80 % (cut-off time 0.45 s), respectively. Bolus propagation speed and time differences between contrast material peaks in the PA can identify PH. This method could be used to confirm the indication for RHC in patients screened for pulmonary hypertension. (orig.)

Non-invasive determination of pulmonary hypertension with dynamic contrast-enhanced computed tomography: a pilot study

Energy Technology Data Exchange (ETDEWEB)

Pienn, Michael; Balint, Zoltan [Ludwig Boltzmann Institute for Lung Vascular Research, Graz (Austria); Kovacs, Gabor; Tscherner, Maria; Olschewski, Horst [Ludwig Boltzmann Institute for Lung Vascular Research, Graz (Austria); Medical University of Graz, Division of Pulmonology, Department of Internal Medicine, Graz (Austria); Avian, Alexander [Ludwig Boltzmann Institute for Lung Vascular Research, Graz (Austria); Medical University of Graz, Institute for Medical Informatics, Statistics and Documentation, Graz (Austria); Johnson, Thorsten R. [Ludwig Maximilians University, Department of Clinical Radiology, Munich (Germany); Kullnig, Peter [DiagnostikZentrum Graz, Graz (Austria); Stollberger, Rudolf [Graz University of Technology, Institute for Medical Engineering, Graz (Austria); Olschewski, Andrea [Ludwig Boltzmann Institute for Lung Vascular Research, Graz (Austria); Medical University of Graz, Experimental Anesthesiology, Department of Anesthesia and Intensive Care Medicine, Graz (Austria)

2014-03-15

In this pilot study we explored whether contrast-material bolus propagation time and speed in the pulmonary arteries (PAs) determined by dynamic contrast-enhanced computed tomography (DCE-CT) can distinguish between patients with and without pulmonary hypertension (PH). Twenty-three patients (18 with and 5 without PH) were examined with a DCE-CT sequence following their diagnostic or follow-up right-sided heart catheterisation (RHC). X-ray attenuation over time curves were recorded for regions of interest in the main, right and left PA and fitted with a spline fit. Contrast material bolus propagation speeds and time differences between the peak concentrations were compared with haemodynamic parameters from RHC. Bolus speed correlated (ρ = -0.55) with mean pulmonary arterial pressure (mPAP) and showed a good discriminative power between patients with and without PH (cut-off speed 317 mm/s; sensitivity 100 %/specificity 100 %). Additionally, time differences between peaks correlated with mPAP (ρ = 0.64 and 0.49 for right and left PA, respectively) and discrimination was achieved with sensitivity 100 %/specificity 100 % (cut-off time 0.15 s) and sensitivity 93 %/specificity 80 % (cut-off time 0.45 s), respectively. Bolus propagation speed and time differences between contrast material peaks in the PA can identify PH. This method could be used to confirm the indication for RHC in patients screened for pulmonary hypertension. (orig.)

Relaciones citotaxonómicas entre Paspalum almum Chase y P. hexastachyum Parodi (Gramineae

Directory of Open Access Journals (Sweden)

Camilo L Quarín

1974-01-01

Full Text Available El autor describe el grupo Alrna del género Paspalum, sobre la base de un manuscrito de Parodi y Nicora (1966. Lleva a cabo un estudio morfológico y citológico de las dos especies que constituyen este grupo: P.almum Chase y Parodi P.hexastachyurn.  P.alrnum presenta veinticuatro cromosomas somáticos y en Metafase I, se comporta como una especie autotetraploide formada a 6 IV's. Aquí se informa, por primera vez, un recuento cromosómico de P.hexastachyum (2n = 12. Este es el número más bajo, conocido para el género Paspalum, lo que confirma la presencia del número básico x = 6, a diferencia del más frecuente en el género, que es x = 10.

Dosimetry characterization and clinical application of Exa skin: Bolus of high of high density for use with photons; Caracterizacion dosimetrica y aplicacion clinica de Exaskin: bolus de alta densidad para uso con fotones

Energy Technology Data Exchange (ETDEWEB)

Ortiz Seidel, M.; Velazquez Miranda, S.

2013-07-01

Bolus of high density eXaSkin of density 1.6 g/cm{sub 3} is calculated correctly in the planning systems, is easy to use and generates optimum coupling with the radiation area, at the same time which is easily reproducible in their placement, avoiding the use of electron beams. On the other hand its behavior varies very slightly with the presence of air gaps. (Author)

Therapeutic efficacy and toxicity of bolus application of chemotherapy protocol in the treatment of metastatic colorectal cancer.

Science.gov (United States)

Šišić, Ibrahim; Pojskić, Belma; Mekić Abazović, Alma; Kovčin, Vladimir

2015-08-01

To compare efficacy and toxicity of bolus application of chemotherapy protocol, oxaliplatin, fluorouracil (bolus), leucovorin (folfox) between two groups of patients in the therapy of metastatic colorectal carcinoma (mCRC). A total of 63 patients were treated for mCRC in the period January 2009 - January 2010 at the Department of Oncology of the Cantonal Hospital Zenica, Bosnia and Herzegovina (first group, 30 patients) and at the Department of Oncology of the Clinical Hospital Centre Bežanijska kosa in Belgrade, Serbia, in the period January 2005 - January 2006 (second group, 33 patients). The patients were treated according the same protocol, i.v. bolus infusion, but in different day intervals (D), 1, 8, 15/28 days or D1-D5/28 days, respectively. In all patients the following factors were analyzed: tumor response, overall survival (OS), progression free survival, hematological and non-hematological toxicity . Colon was the primary localization in almost two thirds of patients. There was no statistically significant difference between the groups according to the age, hematological and non-hematological toxicity, as well as in achieved OS. Progression free survival expressed in months was in average 5 months though with a large range between minimal and maximal survival time. Both groups have shown equivalent efficacy to applied chemotherapy protocols. Overall survival in the two groups matched data from the literature. Further research should confirm success of the combination of chemotherapy protocols and their combination with the biological therapy. Copyright© by the Medical Assotiation of Zenica-Doboj Canton.

Therapeutic efficacy and toxicity of bolus application of chemotherapy protocol in the treatment of metastatic colorectal cancer

Directory of Open Access Journals (Sweden)

Ibrahim Šišić

2015-08-01

Full Text Available Aim To compare efficacy and toxicity of bolus application of chemotherapy protocol, oxaliplatin, fluorouracil (bolus, leucovorin (folfox between two groups of patients in the therapy of metastatic colorectal carcinoma (mCRC. Methods A total of 63 patients were treated for mCRC in the period January 2009 – January 2010 at the Department of Oncology of the Cantonal Hospital Zenica, Bosnia and Herzegovina (first group, 30 patients and at the Department of Oncology of the Clinical Hospital Centre Bežanijska kosa in Belgrade, Serbia, in the period January 2005 – January 2006 (second group, 33 patients. The patients were treated according the same protocol, i.v. bolus infusion, but in different day intervals (D, 1, 8, 15/28 days or D1-D5/28 days, respectively. In all patients the following factors were analyzed: tumor response, overall survival (OS, progression free survival, hematological and non-hematological toxicity. Results Colon was the primary localization in almost two thirds of patients. There was no statistically significant difference between the groups according to the age, hematological and non-hematological toxicity, as well as in achieved OS. Progression free survival expressed in months was in average 5 months though with a large range between minimal and maximal survival time. Conclusion Both groups have shown equivalent efficacy to applied chemotherapy protocols. Overall survival in the two groups matched data from the literature. Further research should confirm success of the combination of chemotherapy protocols and their combination with the biological therapy.

Comparison of Intermittent and Bolus Enteral Feeding Methods on Enteral Feeding Intolerance of Patients with Sepsis: A Triple-blind Controlled Trial in Intensive Care Units.

Science.gov (United States)

Nasiri, Morteza; Farsi, Zahra; Ahangari, Mojtaba; Dadgari, Fahimeh

2017-10-01

BACKGROUND Recent trials have shown controversial results on which enteral feeding methods has a lower risk of enteral feeding intolerance. Therefore, we aimed to compare two methods of bolus and intermittent feeding on enteral feeding intolerance of patients with sepsis. METHODS This triple-blind randomized controlled trial was conducted on 60 patients with sepsis, who were fed through tubes for at least 3 days. The patients were randomly assigned into bolus feeding, intermittent feeding, and control groups. Enteral feeding intolerance of all patients was recorded in 3 consecutive days by a researcher-made checklist including the data on gastric residual volume, vomiting, diarrhea, constipation, and abdominal distension. RESULTS There were no significant differences between the three studied groups in none of the intervention days pertaining to constipation, diarrhea, vomiting, abdominal distention, and gastric residual volume ( p > 0.05). Also, no statistically significant difference was found between all variables in the three studied groups during the 3 days ( p > 0.05). CONCLUSION As enteral feeding intolerance of patients with sepsis was similar in both bolus and intermittent feeding methods, it can be concluded that bolus method can still be used as a standard method to decrease the risk of enteral feeding intolerance if it is used properly.

Taste enhancement in food gels: Effect of fracture properties on oral breakdown, bolus formation and sweetness intensity

NARCIS (Netherlands)

Mosca, A.C.; Velde, van de F.; Bult, J.H.F.; Boekel, van M.A.J.S.; Stieger, M.A.

2015-01-01

This study investigates the effects of fracture strain and fracture stress on oral breakdown, bolus formation and sweetness intensity of semi-solid food gels containing sucrose heterogeneously distributed in layers. The sweetness intensity of gels was mainly affected by the total surface area of gel

Effect of Admission Oral Diuretic Dose on Response to Continuous versus Bolus Intravenous Diuretics in Acute Heart Failure: An Analysis from DOSE-AHF

Science.gov (United States)

Shah, Ravi V.; McNulty, Steven; O'Connor, Christopher M.; Felker, G. Michael; Braunwald, Eugene; Givertz, Michael M.

2014-01-01

Background Results from the Diuretic Optimization Strategies in Acute Heart Failure (DOSE-AHF) study suggest that an initial continuous infusion of loop diuretics is not superior to bolus dosing with regard to clinical endpoints in AHF. We hypothesized that outpatient furosemide dose was associated with congestion and poorer renal function, and explored the hypothesis that a continuous infusion may be more effective in patients on higher outpatient diuretic doses. Methods DOSE-AHF randomized 308 patients within 24 hours of admission to high vs. low initial intravenous diuretic dose given as either a continuous infusion or bolus. We compared baseline characteristics and assessed associations between mode of administration (bolus vs. continuous) and outcomes in patients receiving high-dose (≥120 mg furosemide equivalent, n=177) versus low-dose (diuretics. Results Patients on higher doses of furosemide were less frequently on renin-angiotensin system inhibitors (P=.01), and had worse renal function and more advanced symptoms. There was a significant interaction between outpatient dose and mode of therapy (P=0.01) with respect to net fluid loss at 72 hours after adjusting for creatinine and intensification strategy. Admission diuretic dose was associated with an increased risk of death or rehospitalization at 60 days (adjusted HR=1.08 per 20-mg increment in dose, 95% CI 1.01–1.16, P=.03). Conclusions In acute HF, patients on higher diuretic doses have greater disease severity, and may benefit from an initial bolus strategy. PMID:23194486

Effects of advanced carbohydrate counting guided by an automated bolus calculator in Type 1 diabetes mellitus (StenoABC)

DEFF Research Database (Denmark)

Hommel, E; Schmidt, S; Vistisen, D

2017-01-01

-centre, investigator-initiated clinical study. We enrolled advanced carbohydrate counting-naïve adults with Type 1 diabetes and HbA1c levels 64-100 mmol/mol (8.0-11.3%), who were receiving multiple daily insulin injection therapy. In a 1:1-ratio, participants were randomized to receive training in either advanced......AIMS: To test whether concomitant use of an automated bolus calculator for people with Type 1 diabetes carrying out advanced carbohydrate counting would induce further improvements in metabolic control. METHODS: We conducted a 12-month, randomized, parallel-group, open-label, single...... carbohydrate counting using mental calculations (MC group) or advanced carbohydrate counting using an automated bolus calculator (ABC group) during a 3.5-h group training course. For 12 months after training, participants attended a specialized diabetes centre quarterly. The primary outcome was change in HbA1c...

Multi-Detector Computed Tomography Imaging Techniques in Arterial Injuries

Directory of Open Access Journals (Sweden)

Cameron Adler

2018-04-01

Full Text Available Cross-sectional imaging has become a critical aspect in the evaluation of arterial injuries. In particular, angiography using computed tomography (CT is the imaging of choice. A variety of techniques and options are available when evaluating for arterial injuries. Techniques involve contrast bolus, various phases of contrast enhancement, multiplanar reconstruction, volume rendering, and maximum intensity projection. After the images are rendered, a variety of features may be seen that diagnose the injury. This article provides a general overview of the techniques, important findings, and pitfalls in cross sectional imaging of arterial imaging, particularly in relation to computed tomography. In addition, the future directions of computed tomography, including a few techniques in the process of development, is also discussed.

Study and establishment of a computer program for radiotherapy treatment planning development

International Nuclear Information System (INIS)

Djennaoui, N.

1987-02-01

The modern radiotherapy requires the use of computers. In addition to their accuracy, computers involve an appreciable saving of time in the calculation of isodoses, permitting us to change several times a technique in order to choose the best dose distribution for each case of tumor. The aim of this work was to set a computer program calculating a suitable dose distribution for a given treatment. The algorithm of calculation of the depth dose used in our program permits us to calculate the dose distribution for all photon energies used in radiotherapy, whatever are the energy and modification of the field by the use of wedge filters or bolus [fr

Short-term exposure to repeated chasing stress does not induce habituation in Senegalese sole, Solea senegalensis

DEFF Research Database (Denmark)

Conde-Sieira, Marta; Valente, Luisa M.P.; Hernandez-Perez, Juan

2018-01-01

Animals can habituate to certain repeated stressors and reduce the physiological response that such stressor evoked initially. Studies related to stress habituation in fish are scarce and the available data differ depending on the species and on the type, duration and severity of the stressor...... no significant changes in serotonergic activity. However, incremented serotonergic activity was detected in fish previously trained. Furthermore, dopaminergic activity decreased in diurnal trained and nocturnal trained groups with respect to ST/naïve fish. Crh expression in hypothalamus was higher in ST...... for the animals to habituate, indicating that repeated chasing within short periods should be avoided when manipulating fish in order to keep proper welfare conditions in this species....

Discounting the duration of bolus exposure in impedance testing underestimates acid reflux.

Science.gov (United States)

Vikneswaran, Namasivayam; Murray, Joseph A

2016-06-08

Combined impedance-pH testing (MII) allows for detection of reflux episodes regardless of pH. However impedance-based diagnosis of reflux may not routinely account for duration of the reflux episode. We hypothesize that impedance testing may be less sensitive than pH-testing in detecting acid reflux off therapy as a result of discounting duration of exposure. Baseline characteristics and reflux parameters of MII studies performed off-anti-secretory medications were analyzed. Studies on acid suppressive medication and those with recording times less than 20 h or low baseline impedance were excluded. A total of 73 consecutive MII studies were analyzed of which 31 MII studies had elevated acid exposure while 16 were abnormal by impedance criteria. MII testing off-therapy was more likely to be abnormal by pH criteria (percent time pH reflux):[42 vs 22 % (p =0.02)]. Acid exposure (percent time pH acid reflux episodes [42 vs 34 % (p acid clearance time (pH-detected) was significantly longer than median bolus clearance time (impedance-detected) in the total [98.7 s vs 12.6 s (p acid clearance time (pH-detected) and the median bolus clearance time (impedance-detected) was significantly higher in the recumbent position compared to the upright position [11. vs 5.3 (p = 0.01)]. Ambulatory impedance testing underestimates acid reflux compared to esophageal acid exposure by discounting the prolonged period of mucosal contact with each acid reflux episode, particularly in the recumbent position.

Optimum bolus wizard settings in insulin pumps in children with Type 1 diabetes

DEFF Research Database (Denmark)

Andersen, A J B; Ostenfeld, A; Pipper, C B

2016-01-01

: Optimum insulin pump settings at pump initiation depend on both insulin requirements and use of the pump. Settings need to be individualized because the standardized calculation factors are not constant for children. There is a need to develop specific age- and insulin dose-dependent calculation factors.......AIM: To evaluate current insulin pump settings in an optimally regulated paediatric population using bolus wizard. METHODS: We used a retrospective study design to analyse data from 124 children on insulin pump therapy who had optimum HbA1c levels [

Split-bolus CT-urography using dual-energy CT: Feasibility, image quality and dose reduction

Energy Technology Data Exchange (ETDEWEB)

Takeuchi, Mitsuru, E-mail: m2rbimn@gmail.com [Nagoya City University Graduate School of Medical Sciences, Department of Radiology, 1 Kawasumi Mizuho-cho, Mizuho-ku, Nagoya, 467-8601 (Japan); Kawai, Tatsuya; Ito, Masato; Ogawa, Masaki [Nagoya City University Graduate School of Medical Sciences, Department of Radiology, 1 Kawasumi Mizuho-cho, Mizuho-ku, Nagoya, 467-8601 (Japan); Ohashi, Kazuya [Nagoya City University Hospital, Department of Radiology, 1 Kawasumi Mizuho-cho, Mizuho-ku, Nagoya, 467-8601 (Japan); Hara, Masaki; Shibamoto, Yuta [Nagoya City University Graduate School of Medical Sciences, Department of Radiology, 1 Kawasumi Mizuho-cho, Mizuho-ku, Nagoya, 467-8601 (Japan)

2012-11-15

Purpose: To prospectively evaluate the feasibility of dual-energy (DE) split-bolus CT-urography (CTU) and the quality of virtual non-enhanced images (VNEI) and DE combined nephrographic-excretory phase images (CNEPI), and to estimate radiation dose reduction if true non-enhanced images (TNEI) could be omitted. Patients and methods: Between August and September 2011, 30 consecutive patients with confirmed or suspected urothelial cancer or with hematuria underwent DE CT. Single-energy TNEI and DE CNEPI were obtained. VNEI was reconstructed from CNEPI. Image quality of CNEPI and VNEI was evaluated using a 5-point scale. The attenuation of urine in the bladder on TNEI and VNEI was measured. The CT dose index volume (CTDI (vol)) of the two scans was recorded. Results: The mean image quality score of CNEPI and VNEI was 4.7 and 3.3, respectively. The mean differences in urine attenuation between VNEI and TNEI were 14 {+-} 15 [SD] and -16 {+-} 29 in the anterior and posterior parts of the bladder, respectively. The mean CTDI (vol) for TNEI and CNEPI was 11.8 and 10.9 mGy, respectively. Omission of TNEI could reduce the total radiation dose by 52%. Conclusion: DE split-bolus CTU is technically feasible and can reduce radiation exposure; however, an additional TNEI scan is necessary when the VNEI quality is poor or quantitative evaluation of urine attenuation is required.

Precision flow-controlled Rb-82 generator for bolus or constant-infusion studies of the heart and brain

International Nuclear Information System (INIS)

Yano, Y.; Cahoon, J.L.; Budinger, T.F.

1981-01-01

A precision flow-controlled rubidium-82 generator has been constructed to deliver 76-sec Rb-82 at either fast or slow flow rates for bolus or constant-infusion studies. A stepping motor drive is interfaced to a microprocessor for pulsed control of flow rate to deliver the saline eluant solution from a large-volume (150 ml) machined pumping syringe through an alumina column that retains the 25-day Sr-82 parent. The generator system delivers 70-90% of the maximum Rb-82 activity in a 20-25 ml bolus elution of 2% NaCl. The Sr-82/Sr-85 breakthrough is 10 -7 - 10 -6 . Both yield and breakthrough are functions of column length and flow rate. Six separate Sr-82 loadings of the generator were evaluated over a period of nearly 2 yr in studies of myocardial blood perfusion and permeability changes in the blood-brain barrier. Sterility and apyrogenicity of the Rb-82 eluate were maintained during multiple elutions and long-term use of 3-4 mo for each generator loading

Finns det nån här? – Förmedling av paranormala fenomen i TV-serien Chasing the Dead

OpenAIRE

Heinänen, Thomas

2013-01-01

Genom denna kvalitativa innehållsanalys av TV-serien Chasing the Dead, undersöks på vilket sätt dokumenterade "bevis" på paranormala audiovisuella fenomen har presenterats av seriemakarna. Materialet analyseras med hjälp av forskningsresultat från, för denna TV-genre relevanta, studier av fenomen som Electronic Voice Phenomenon, Electro Magnetic Field, Orber. Biologiska fenomen som Apophenia och Pareidolia har tagits i beaktande då materialet har analyserats. Syftet med denna underso...

GammeV and GammeV-CHASE

International Nuclear Information System (INIS)

Wester, W.

2011-01-01

Physics beyond the Standard Model might include Weakly Interacting Slim Particles (WISPs) that address questions such as what is the nature of dark matter or even shed insight into the underlying nature of dark energy. WISPs are a general class of particles that include axions, axion-like particles, hidden sector photons, milli-charged particles, chameleons, etc. The GammeV (Gamma to milli-eV) experiment originated in 2007 in order to test a positive anomalous axion-like particle interpretation of the PVLAS experiment which was not evident in subsequent data. The experiment was also motivated as it was realized that the milli-eV scale appears naturally in a see-saw between the electroweak and Planck scales, neutrino mass differences, the dark energy density, and the possible mass for certain dark matter candidates. GammeV was first to exclude both a scalar and pseudoscalar axion-like particle interpretation of the anomalous PVLAS result setting a limit of around 3.1 x 10 -7 GeV -1 on the coupling to photons for low mass axion-like particles. It has also been found that the parameter space of a variety of other WISP candidates is both largely unexplored and is accessible by modest experiments employing lasers and possibly accelerator magnets. GammeV data has also been used to set limits on possible hidden sector photons. Further work by the GammeV team has focused on a reconfiguration of the apparatus to be sensitive to possible chameleon particles. Chameleons are scalar (or pseudoscalar) particles that couple to the stress energy tensor in a potential such that their properties depend on their environment. In particular, a chameleon acquires an effective mass which increases with local matter density, ρ. For a certain class of such potentials, the chameleon field has properties that might explain dark energy. GammeV set the first limits on the coupling of chameleons to photons. A dedicated follow-up experiment, GammeV-CHASE, (CHameleon Afterglow SEarch), has also

Contrast bolus technique with rapid CT scanning

International Nuclear Information System (INIS)

Arnold, H.; Kuehne, D.; Rohr, W.; Heller, M.

1981-01-01

Twenty-three patients complying with the clinical criteria for brain death were studied by contrast-enhanced CT. In all but one, the great intracranial vessels escaped visualization; accordingly, angiography demonstrated cerebral circulatory arrest. In the remaining case, faint enhancement of the circle of Willis corresponded to angiographic demonstration of the proximal segments of cerebral arteris. Neither in normal brain nor in dead brain did slow CT scanning disclose any postcontrast increase in parenchymal attenuation. An improved technique is proposed to demonstrate the transit of the contrast bolus by rapid CT with image splitting. If cerebral blood flow is preserved, the grey and white matter will enhance significantly following administration of contrast medium. Vice versa, the absence of enhancement confirms brain death, even in instances in which the great cerebral vessels are obscured by hemorrhage or other extensive lesions. Two additional cases of brain death were evaluated by rapid CT scanning. As to brain death, the technique obviates the need for angiography or radionuclide angiography, usually applied in prospective organ donors, because its informative content is superior to that of either method. The CT technique described affords a reliable and safe diagnosis of brain death, and can be interpreted easily. (orig.)

Micropropagation of Gerbera (Gerbera jamesonii Bolus).

Science.gov (United States)

Minerva, Ghani; Kumar, Surinder

2013-01-01

Gerbera (Gerbera jamesonii Bolus) is one of the most popular ornamental flowers worldwide and used both as cut flower and potted plant. Some of them show excellent agronomic characters such as color, floral diameter, stem length, and vigor, which make this plant of commercial importance. Conventionally, multiplication is done through seeds or rhizome cuttings. Rapid multiplication of elite cultivars of Gerbera, with improved agronomic traits, has been achieved by using both direct and indirect tissue culture methods. Direct shoot regeneration was accomplished from stem apices on MS medium supplemented with 1 mg/L 6-benzyladenine (BA) and 1 mg/L kinetin. Indirect shoot induction succeeded from callus differentiation has been achieved on MS medium containing 2 mg/L 2,4-dichlorophenoxyacetic acid, 0.5 mg/L indole-3-acetic acid, and 2 mg/L BA. The in vitro shoots, 4-5 cm long, were rooted by quick dipping the shoot bases for 3-5 s in 2,000 mg/L indole-3-butyric acid solution followed by transfer to the pots containing farmyard manure, soil, and sand (1:1:1 by volume). Initially, in vitro plantlets were covered with glass jars to maintain a high relative humidity (85-90%). As soon as new shoot growth begins, relative humidity is decreased by exposing them to the open environmental conditions prior transferring to the glasshouse. Indirect shoot regeneration increased the frequency of somaclonal variations. The selected somaclones were used in developing new and novel cultivars.

Bolus dose response characteristics of single chain urokinase plasminogen activator and tissue plasminogen activator in a dog model of arterial thrombosis.

Science.gov (United States)

Badylak, S F; Voytik, S; Klabunde, R E; Henkin, J; Leski, M

1988-11-15

Tissue plasminogen activator (t-PA) and single chain urokinase-plasminogen activator (scu-PA) are relatively "fibrin-specific" thrombolytic drugs with short plasma half lives of 6-8 minutes. Most treatment regimens with these agents utilize a bolus injection followed by continuous drug infusion, usually combined with anticoagulant therapy. The purpose of this study was to establish the dose-response characteristics for scu-PA and t-PA, when given as a single intravenous bolus injection, in a dog model of arterial thrombosis. Eight groups of 6 dogs each were given one of the following doses of scu-PA (mg/kg): 0.20, 0.50, 1.00, 2.00; or t-PA: 0.05, 0.10, 0.20; or an equivalent amount of saline (control group). All doses were given as a single bolus injection 60 minutes after formation of a totally occlusive femoral artery thrombus. Thrombolysis was measured by monitoring the continuous decrement of 125I activity from a radiolabelled thrombus. Ninety minutes after drug injection, all scu-PA treated dogs showed greater thrombolysis (30%, 45%, 56%, and 67%, respectively) than the control group (15%, p less than 0.01). The 0.10 and 0.20 mg/kg t-PA treated dogs showed greater thrombolysis (35% and 49%, respectively) than the control group (15%, p less than 0.01). Both scu-PA and t-PA caused a partial and dose-dependent decrease in alpha 2-antiplasmin activity but scu-PA caused a greater depletion (72% vs. 18%, respectively, p less than 0.05) at 60 minutes after the highest dose of drug administration. Both drugs showed a longer than expected thrombolytic effect based upon the known half lives. Neither drug caused significant changes in the prothrombin time, activated partial thromboplastin time, thrombin time, hematocrit, platelet count, or fibrin degradation product concentration. Single bolus injections of scu-PA and t-PA produce safe and effective thrombolysis in this dog model of arterial thrombosis.

Dual-energy CT iodine maps as an alternative quantitative imaging biomarker to abdominal CT perfusion: determination of appropriate trigger delays for acquisition using bolus tracking.

Science.gov (United States)

Skornitzke, Stephan; Fritz, Franziska; Mayer, Philipp; Koell, Marco; Hansen, Jens; Pahn, Gregor; Hackert, Thilo; Kauczor, Hans-Ulrich; Stiller, Wolfram

2018-05-01

Quantitative evaluation of different bolus tracking trigger delays for acquisition of dual energy (DE) CT iodine maps as an alternative to CT perfusion. Prior to this retrospective analysis of prospectively acquired data, DECT perfusion sequences were dynamically acquired in 22 patients with pancreatic carcinoma using dual source CT at 80/140 kV p with tin filtration. After deformable motion-correction, perfusion maps of blood flow (BF) were calculated from 80 kV p image series of DECT, and iodine maps were calculated for each of the 34 DECT acquisitions per patient. BF and iodine concentrations were measured in healthy pancreatic tissue and carcinoma. To evaluate potential DECT acquisition triggered by bolus tracking, measured iodine concentrations from the 34 DECT acquisitions per patient corresponding to different trigger delays were assessed for correlation to BF and intergroup differences between tissue types depending on acquisition time. Average BF measured in healthy pancreatic tissue and carcinoma was 87.6 ± 28.4 and 38.6 ± 22.2 ml/100 ml min -1 , respectively. Correlation between iodine concentrations and BF was statistically significant for bolus tracking with trigger delay greater than 0 s (r max = 0.89; p alternative to CT perfusion measurements of BF. Advances in knowledge: After clinical validation, DECT iodine maps of pancreas acquired using bolus tracking with appropriate trigger delay as determined in this study could offer an alternative quantitative imaging biomarker providing functional information for tumor assessment at reduced patient radiation exposure compared to CT perfusion measurements of BF.

ANALGESIC EFFECT OF INTRATHECAL BACLOFEN BOLUS ON NEUROPATHIC PAIN IN SPINAL CORD INJURY PATIENTS.

Science.gov (United States)

Kumru, Hatice; Benito-Penalva, Jesus; Kofler, Markus; Vidal, Joan

2018-05-18

GABA-ergic neurons are widely distributed throughout the central nervous system, including the spinal cord which is important for the transmission of pain impulses to the brain. Here we hypothesized that intrathecal baclofen (ITB) which is a GABA analogue might exert analgesic effects on neuropathic pain, which could be related to subtypes of pain in spinal cord injury (SCI). SCI patients with a cervical or thoracic lesion and neuropathic pain were randomized to receive either a single ITB bolus or placebo. Numerical Rating Scale (NRS), Neuropathic Pain Symptom Inventory (NPSI), and Brief Pain Inventory (BPI) were obtained for assessment of neuropathic pain. Spasticity was assessed using Modified Ashworth Scale and visual analogue scale. Evaluations were performed at baseline, and 4, 8, and 24 hours after application of ITB or placebo. Eight patients received ITB, 5 placebo. Neuropathic pain improved significantly in the ITB group based on NRS, BPI, and NPSI, which revealed an effect on all subtypes of pain. Spasticity declined significantly. In the placebo group, there was neither significant change in pain nor in spasticity. An ITB bolus exerted a significant analgesic effect on all subtypes of neuropathic pain in SCI patients. ITB has analgesic effects on all subtypes of neuropathic pain and can improve interference of neuropathic pain with activities of daily living. ITB might be a promising analgesic treatment to control neuropathic pain. Copyright © 2018. Published by Elsevier Inc.

Optimization of coronary attenuation in coronary computed tomography angiography using diluted contrast material.

Science.gov (United States)

Kawaguchi, Naoto; Kurata, Akira; Kido, Teruhito; Nishiyama, Yoshiko; Kido, Tomoyuki; Miyagawa, Masao; Ogimoto, Akiyoshi; Mochizuki, Teruhito

2014-01-01

The purpose of this study was to evaluate a personalized protocol with diluted contrast material (CM) for coronary computed tomography angiography (CTA). One hundred patients with suspected coronary artery disease underwent retrospective electrocardiogram-gated coronary CTA on a 256-slice multidetector-row CT scanner. In the diluted CM protocol (n=50), the optimal scan timing and CM dilution rate were determined by the timing bolus scan, with 20% CM dilution (5ml/s during 10s) being considered suitable to achieve the target arterial attenuation of 350 Hounsfield units (HU). In the body weight (BW)-adjusted protocol (n=50, 222mg iodine/kg), only the optimal scan timing was determined by the timing bolus scan. The injection rate and volume in the timing bolus scan and real scan were identical between the 2 protocols. We compared the means and variations in coronary attenuation between the 2 protocols. Coronary attenuation (mean±SD) in the diluted CM and BW-adjusted protocols was 346.1±23.9 HU and 298.8±45.2 HU, respectively. The diluted CM protocol provided significantly higher coronary attenuation and lower variance than did the BW-adjusted protocol (P<0.05, in each). The diluted CM protocol facilitates more uniform attenuation on coronary CTA in comparison with the BW-adjusted protocol.  

Bolus effect to reduce skin dose of the caontralateral breast during breast cancer radiation therapy

Energy Technology Data Exchange (ETDEWEB)

Won, Young Jin [Dept. of Radiation Oncology, InJe University Ilsan Paik Hospital, Goyang (Korea, Republic of); Kim, Jong Won; Kim, Jung Hoon [Dept. of Radiology, Radiation Oncology, KonYang University Hospital, Daejeon (Korea, Republic of)

2017-06-15

The aim of this study was to evaluate the dose comparison using Radon phantom with 5 mm and 10 mm tissue equivalent materials, FIF, Wedge(15, 30 angle) and IMRT, to reduce the skin dose of the contralateral breast during breast cancer radiation therapy(Total dose: 50.4Gy). The dose was measured for each treatment plan by attaching to the 8 point of the contralateral breast of the treated region using a optical-stimulated luminance dosimeter(OSLD) as a comparative dose evaluation method. Of the OSLD used in the study, 10 were used with reproducibility within 3%. As a result, the average reduction rates of 5 mm and 10 mm in the FIF treatment plan were 37.23 cGy and 41.77 cGy, respectively, and the average reduction rates in the treatment plan using Wedge 15 degrees were 70.69 cGy and 87.57 cGy, respectively. The IMRT showed a reduction of 67.37 cGy and 83.17 cGy, respectively. The results of using bolus showed that as the thickness of the bolus increased in all treatments, the dose reduction increased. We concluded that mastectomy as well as general radiotherapy for breast cancer would be very effective for patients who are more likely to be exposed to scattered radiation due to a more demanding or complex treatment plan.

Nonlinear pharmacokinetics of visnagin in rats after intravenous bolus administration.

Science.gov (United States)

Haug, Karin G; Weber, Benjamin; Hochhaus, Guenther; Butterweck, Veronika

2012-01-23

Ammi visnaga L. (syn. Khella, Apiaceae) preparations have traditionally been used in the Middle East for the treatment of kidney stone disease. Visnagin, a furanocoumarin derivative, is one of the main compounds of Ammi visnaga with potential effects on kidney stone prevention. To date, no information is available about the pharmacokinetic (PK) properties of visnagin. It was the aim of the study to characterize the PK properties of visnagin after intravenous (i.v.) bolus administration in rats and to develop an adequate model for the description of the observed data, including model parameter estimates. Therefore, three doses of visnagin (1.25, 2.5, and 5mg/kg) solubilized in 25% Captisol® were administered by i.v. bolus injection to male Sprague-Dawley rats. Plasma samples were extracted and subsequently analyzed using a validated LC-MS/MS method. Both non-compartmental and compartmental PK analyses were performed. A stepwise model building approach was applied including nonlinear mixed effect modeling for final model selection and to obtain final model estimates in NONMEM VI. The average areas under the curve (AUC(0-last)) after doses of 1.25, 2.5, and 5mg/kg were 1.03, 3.61, and 12.6 mg *h/l, respectively. The shape of the plasma concentration-time profiles and the observed disproportionate increase in AUC(0-last) with increasing dose suggested nonlinearity in the elimination of visnagin. A two-compartment Michaelis-Menten model provided the best fit with following typical values of the parameter estimates: 2.09 mg/(l*h) (V(max)), 0.08 mg/l (K(M)), 0.175 l (V(C)), 1.0 h⁻¹ (k₁₂), and 1.22 h⁻¹ (k₂₁). Associated inter-subject variability estimates (% CV) for V(max), K(M) and V(C) were 21.8, 70.9, and 9.2, respectively. Intra-subject variability (constant CV error model) was estimated to be 7.0%. The results suggest the involvement of a saturable process in the elimination of visnagin, possibly an enzyme or transporter system. Copyright © 2011

Relationship between esophageal contraction patterns and clearance of swallowed liquid and solid boluses in healthy controls and patients with dysphagia

NARCIS (Netherlands)

Bogte, A.; Bredenoord, A. J.; Oors, J.; Siersema, P. D.; Smout, A. J. P. M.

2012-01-01

Background Non-obstructive dysphagia patients prove to be a difficult category for clinical management. Esophageal high-resolution manometry (HRM) is a novel method, used to analyze dysphagia. However, it is not yet clear how findings on HRM relate to bolus transport through the esophagus. Methods

Associations between bolus infusion of hydrocortisone, glycemic variability and insulin infusion rate variability in critically Ill patients under moderate glycemic control

NARCIS (Netherlands)

van Hooijdonk, Roosmarijn T. M.; Binnekade, Jan M.; Bos, Lieuwe D. J.; Horn, Janneke; Juffermans, Nicole P.; Abu-Hanna, Ameen; Schultz, Marcus J.

2015-01-01

We retrospectively studied associations between bolus infusion of hydrocortisone and variability of the blood glucose level and changes in insulin rates in intensive care unit (ICU) patients. 'Glycemic variability' and 'insulin infusion rate variability' were calculated from and expressed as the

Alveolar echinococcosis of the liver - computed tomographic findings

International Nuclear Information System (INIS)

Merkle, E.; Usadel, S.; Vogel, J.; Kern, P.; Friedrich, J.M.; Brambs, H.J.

1995-01-01

In order to ascertain the typical computed tomographic findings of hepatic alveolar echinococcosis, 24 computed tomograms of 19 patients were evaluated. The liver was involved in all cases whereas the diaphragma was infiltrated in 32%, and the retroperioteneal area in 42%. The right liver lobe was affected in 65%. Both before and after intravenous bolus contrast medium administration, the lesions were mainly inhomogeneous and of low density; a masking of the lesions due to the contrast medium administration was not observed; the enhancement pattern was irregular. Calcifications were detected in 96% of the cases, cystic structures in 50%, and cholestasis in 54%. On the basis of the crucial finding of calcifications in combination with the other typical observations, CT seems to be very suitable for the evaluation of hepatic alveolar echinococcosis. (orig.) [de

Changes in basal rates and bolus calculator settings in insulin pumps during pregnancy in women with type 1 diabetes

DEFF Research Database (Denmark)

Mathiesen, Jonathan M; Secher, Anna L; Ringholm, Lene

2014-01-01

OBJECTIVE: To explore insulin pump settings in a cohort of pregnant women with type 1 diabetes on insulin pump therapy with a bolus calculator. METHODS: Twenty-seven women with type 1 diabetes on insulin pump therapy were included in this study. At 8, 12, 21, 27 and 33 weeks, insulin pump setting...

Quantitative Measurement of GPCR Endocytosis via Pulse-Chase Covalent Labeling.

Directory of Open Access Journals (Sweden)

Hidetoshi Kumagai

Full Text Available G protein-coupled receptors (GPCRs play a critical role in many physiological systems and represent one of the largest families of signal-transducing receptors. The number of GPCRs at the cell surface regulates cellular responsiveness to their cognate ligands, and the number of GPCRs, in turn, is dynamically controlled by receptor endocytosis. Recent studies have demonstrated that GPCR endocytosis, in addition to affecting receptor desensitization and resensitization, contributes to acute G protein-mediated signaling. Thus, endocytic GPCR behavior has a significant impact on various aspects of physiology. In this study, we developed a novel GPCR internalization assay to facilitate characterization of endocytic GPCR behavior. We genetically engineered chimeric GPCRs by fusing HaloTag (a catalytically inactive derivative of a bacterial hydrolase to the N-terminal end of the receptor (HT-GPCR. HaloTag has the ability to form a stable covalent bond with synthetic HaloTag ligands that contain fluorophores or a high-affinity handle (such as biotin and the HaloTag reactive linker. We selectively labeled HT-GPCRs at the cell surface with a HaloTag PEG ligand, and this pulse-chase covalent labeling allowed us to directly monitor the relative number of internalized GPCRs after agonist stimulation. Because the endocytic activities of GPCR ligands are not necessarily correlated with their agonistic activities, applying this novel methodology to orphan GPCRs, or even to already characterized GPCRs, will increase the likelihood of identifying currently unknown ligands that have been missed by conventional pharmacological assays.

Evaluation of a commercially available molybdate formulation and zinc oxide boluses in preventing hepatic copper accumulation and thus enzootic icterus in sheep

Directory of Open Access Journals (Sweden)

C.J. Botha

2001-07-01

Full Text Available The efficacy of a molybdate formulation and a zinc oxide bolus as prophylactic agents for enzootic icterus was evaluated in sheep. Before copper loading, liver biopsies were performed on 12 male, 6-month-old, Mutton Merino sheep to determine hepatic copper (Cu and zinc (Zn concentrations. The animals were restrictively randomised according to liver copper concentrations to 3 treatment groups (n = 4 to achieve similar mean liver copper concentrations per group. All sheep received 4 m /kg of a 0.5 %aqueous solution of CuSO4·5H2O intraruminally 7 days per week for 10 weeks. On Day 0 the sheep in the Mo-group were injected subcutaneously with 42 mg molybdenum (Mo contained in a commercial molybdate formulation. The animals in the Zn-group each received a zinc oxide bolus, containing 43 g zinc oxide, via a rumen cannula. Treatment was repeated on Day 42. Four animals served as untreated controls. Urinary copper excretion, plasma copper concentration, haematocrit and glutamate dehydrogenase (GLDH activity were determined throughout the trial. The animals were sacrificed after 10 weeks and liver samples were submitted for histopathological examination. Liver and kidney copper and zinc concentrations were determined. Neither the molybdate treatment nor the zinc oxide boluses prevented hepatic copper accumulation. The urinary copper excretion, plasma copper concentration, haematocrit and GLDH activity were not significantly different (P > 0.05 from the controls.

Lung disease severity in idiopathic pulmonary fibrosis is more strongly associated with impedance measures of bolus reflux than pH parameters of acid reflux alone.

Science.gov (United States)

Gavini, S; Borges, L F; Finn, R T; Lo, W-K; Goldberg, H J; Burakoff, R; Feldman, N; Chan, W W

2017-05-01

Gastroesophageal reflux (GER) has been associated with idiopathic pulmonary fibrosis (IPF). Pathogenesis may be related to chronic micro-aspiration. We aimed to assess objective measures of GER on multichannel intraluminal impedance and pH study (MII-pH) and their relationship with pulmonary function testing (PFT) results, and to compare the performance of pH/acid reflux parameters vs corresponding MII/bolus parameters in predicting pulmonary dysfunction in IPF. This was a retrospective cohort study of IPF patients undergoing prelung transplant evaluation with MII-pH off acid suppression, and having received PFT within 3 months. Patients with prior fundoplication were excluded. Severe pulmonary dysfunction was defined using diffusion capacity of the lung for carbon monoxide (DLCO) ≤40%. Six pH/acid reflux parameters with corresponding MII/bolus reflux measures were specified a priori. Multivariate analyses were applied using forward stepwise logistic regression. Predictive value of each parameter for severe pulmonary dysfunction was calculated by area-under-the-receiver-operating-characteristic-curve or c-statistic. Forty-five subjects (67% M, age 59, 15 mild-moderate vs 30 severe) met criteria for inclusion. Patient demographics and clinical characteristics were similar between pulmonary dysfunction groups. Abnormal total reflux episodes and prolonged bolus clearance time were significantly associated with pulmonary dysfunction severity on univariate and multivariate analyses. No pH parameters were significant. The c-statistic of each pH parameter was lower than its MII counterpart in predicting pulmonary dysfunction. MII/bolus reflux, but not pH/acid reflux, was associated with pulmonary dysfunction in prelung transplant patients with IPF. MII-pH may be more valuable than pH testing alone in characterizing GER in IPF. © 2016 John Wiley & Sons Ltd.

The regeneration of a multi-ethnic mixed-use area: The case of Robin Hood Chase

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Ian Bentley

1997-01-01

Full Text Available Urban designers show increasing interest in promoting community participation in urban regeneration and especially housing regeneration. However, effective participation has proved difficult in multi-ethnic mixed-use areas, with their wide range of different (and often conflicting interest groups. This paper, presented in case-study form, analyses a project in one such area: the Robin Hood Chase local centre in St. Ann’s area of Nottingham. It pays particular attention to the identification of different interest groups and their associated institutions, the use of local media and social events to involve these groups in the urban design process, the use of rearrangeable models in a process of “enquiry by design”, and the production of a widely acceptable urban design strategy for the area. Analysis of feedback from participants indicates a high level of satisfaction both with the final physical design proposal and with the process itself; and also identifies directions for further development in the approach and techniques employed.

Appropriateness of Bolus Antihypertensive Therapy for Elevated Blood Pressure in the Emergency Department.

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Miller, Joseph B; Arter, Andrew; Wilson, Suprat S; Janke, Alexander T; Brody, Aaron; Reed, Brian P; Levy, Phillip D

2017-08-01

While moderate to severely elevated blood pressure (BP) is present in nearly half of all emergency department (ED) patients, the incidence of true hypertensive emergencies in ED patients is low. Administration of bolus intravenous (IV) antihypertensive treatment to lower BP in patients without a true hypertensive emergency is a wasteful practice that is discouraged by hypertension experts; however, anecdotal evidence suggests this occurs with relatively high frequency. Accordingly, we sought to assess the frequency of inappropriate IV antihypertensive treatment in ED patients with elevated BP absent a hypertensive emergency. We performed a retrospective cohort study from a single, urban, teaching hospital. Using pharmacy records, we identified patients age 18-89 who received IV antihypertensive treatment in the ED. We defined treatment as inappropriate if documented suspicion for an indicated cardiovascular condition or acute end-organ injury was lacking. Data abstraction included adverse events and 30-day readmission rates, and analysis was primarily descriptive. We included a total of 357 patients over an 18-month period. The mean age was 55; 51% were male and 93% black, and 127 (36.4%) were considered inappropriately treated. Overall, labetalol (61%) was the most commonly used medication, followed by enalaprilat (18%), hydralazine (18%), and metoprolol (3%). There were no significant differences between appropriate and inappropriate BP treatment groups in terms of clinical characteristics or adverse events. Hypotension or bradycardia occurred in three (2%) patients in the inappropriate treatment cohort and in two (1%) patients in the appropriately treated cohort. Survival to discharge and 30-day ED revisit rates were equivalent. More than one in three patients who were given IV bolus antihypertensive treatment in the ED received such therapy inappropriately by our definition, suggesting that significant resources could perhaps be saved through education of

Appropriateness of Bolus Antihypertensive Therapy for Elevated Blood Pressure in the Emergency Department

Directory of Open Access Journals (Sweden)

Joseph B. Miller

2017-07-01

Full Text Available Introduction: While moderate to severely elevated blood pressure (BP is present in nearly half of all emergency department (ED patients, the incidence of true hypertensive emergencies in ED patients is low. Administration of bolus intravenous (IV antihypertensive treatment to lower BP in patients without a true hypertensive emergency is a wasteful practice that is discouraged by hypertension experts; however, anecdotal evidence suggests this occurs with relatively high frequency. Accordingly, we sought to assess the frequency of inappropriate IV antihypertensive treatment in ED patients with elevated BP absent a hypertensive emergency. Methods: We performed a retrospective cohort study from a single, urban, teaching hospital. Using pharmacy records, we identified patients age 18–89 who received IV antihypertensive treatment in the ED. We defined treatment as inappropriate if documented suspicion for an indicated cardiovascular condition or acute end-organ injury was lacking. Data abstraction included adverse events and 30-day readmission rates, and analysis was primarily descriptive. Results: We included a total of 357 patients over an 18-month period. The mean age was 55; 51% were male and 93% black, and 127 (36.4% were considered inappropriately treated. Overall, labetalol (61% was the most commonly used medication, followed by enalaprilat (18%, hydralazine (18%, and metoprolol (3%. There were no significant differences between appropriate and inappropriate BP treatment groups in terms of clinical characteristics or adverse events. Hypotension or bradycardia occurred in three (2% patients in the inappropriate treatment cohort and in two (1% patients in the appropriately treated cohort. Survival to discharge and 30-day ED revisit rates were equivalent. Conclusion: More than one in three patients who were given IV bolus antihypertensive treatment in the ED received such therapy inappropriately by our definition, suggesting that significant

Contrast enhancement by arterial perfusion during computed tomography (computed tomographic arteriography) of the pancreatic disease

International Nuclear Information System (INIS)

Takaki, Yukiari

1983-01-01

Computed tomographic arteriography (CTA) was performed on 52 cases of pancreatic disease in which was suspected clinically, and in which other method failed to yield a definitive diagnosis. For CTA, 65% meglumine diatrizoate 20 ml, diluted 1:3, was injected via a catherter inserted in an artery connected with the pancreas and the change with time of the pacreas CT number was studied. The normal pancreas stains deeply and the best contrast enhancement was obtained between 17 to 21 seconds after instillation of contrast medium. In the CTA findings in pancreatic cancer, low density areas with irregular internal structures are characteristic, and these characteristics were seen even in minute pancreatic cancers which could not be recognized by CT or the intravenous bolus injection method. On the other hand, in chronic pancreatitis, even when differentiation from pancreatic cancer is difficult with arterial and venous encasement in angiography, as long as the chronic pancreatitis is not very advanced ischemic changes are not seen, and this permits differentiation form normal pancreas. This also facilitates differentiation between pancreatitis and pancreatic cancer. In the intravenous bolus injection method, the chronological change of contrast enhancement in the pancreas was studied and the best contrast enhancement was obtained after 60 to 120 seconds. This method revealed no findings peculiar to pancreatic cancer. Based on the above, CTA was found to be useful for making in contributing to establishing a definitive diagnosis, detecting minute pancreatic cancer and to differentiate pancreatic cancer from chronic pancreatitis. (author)

Efficacy, distribution and faecal excretion of copper oxide wire particles in a novel bolus in red deer (Cervus elaphus).

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Castillo-Alcala, F; Wilson, P R; Molenaar, R; Lopez-Villalobos, N

2007-04-01

To determine the efficacy of a novel copper oxide wire particle (COWP) formulation in elevating concentrations of copper (Cu) in the liver and serum of red deer (Cervus elaphus), and to investigate the distribution of particles in the gastrointestinal tract and the rate of their excretion in faeces. Mixed-age red deer hinds were allocated to three groups (n=10 per group) on the basis of pre-treatment liver Cu concentrations. Groups 1 and 2 were treated orally with a 10-g COWP bolus on Days 0 and 30, respectively, while the remaining group served as an untreated control. Animals were slaughtered on Day 60, when blood and liver samples were collected for determination of Cu concentrations. An additional group of 18-month-old red deer hinds (n=20) were treated orally with a 10-g COWP bolus, and four were slaughtered on each of Days 1, 5, 15, 30 and 60 after treatment. The gastrointestinal tract was secured between compartments below the oesophagus and contents rinsed until sedimentation of particles was complete. The sediment was oven-dried and COWP were separated and weighed. Faeces were collected continuously from four additional animals held in metabolism cages for 4 days after treatment, sub-sampled daily, and COWP recovered. Mean liver Cu concentrations at slaughter were 80, 597 and 447 micromol/kg for controls and hinds treated 30, and 60 days previously, respectively. Corresponding mean serum Cu concentrations were 7.7, 12.9 and 11.9 micromol/L, respectively. Liver and serum Cu concentrations were higher in both treatment groups than in untreated control animals (p<0.001). COWP were found in all compartments of the gastrointestinal tract measured, for at least 15 days, and in the rumen/reticulum and abomasum for at least 60 days post-administration. The highest rate of recovery overall was from the rumen/reticulum. Mean weight of COWP recovered from faeces was 0.09 g during the first 24 h and 0.94 g over the first 4 days following administration. The COWP bolus

Effect of Bolus Viscosity on the Safety and Efficacy of Swallowing and the Kinematics of the Swallow Response in Patients with Oropharyngeal Dysphagia: White Paper by the European Society for Swallowing Disorders (ESSD).

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Newman, Roger; Vilardell, Natàlia; Clavé, Pere; Speyer, Renée

2016-04-01

Fluid thickening is a well-established management strategy for oropharyngeal dysphagia (OD). However, the effects of thickening agents on the physiology of impaired swallow responses are not fully understood, and there is no agreement on the degree of bolus thickening. To review the literature and to produce a white paper of the European Society for Swallowing Disorders (ESSD) describing the evidence in the literature on the effect that bolus modification has upon the physiology, efficacy and safety of swallowing in adults with OD. A systematic search was performed using the electronic Pubmed and Embase databases. Articles in English available up to July 2015 were considered. The inclusion criteria swallowing studies on adults over 18 years of age; healthy people or patients with oropharyngeal dysphagia; bolus modification; effects of bolus modification on swallow safety (penetration/aspiration) and efficacy; and/or physiology and original articles written in English. The exclusion criteria consisted of oesophageal dysphagia and conference abstracts or presentations. The quality of the selected papers and the level of research evidence were assessed by standard quality assessments. At the end of the selection process, 33 articles were considered. The quality of all included studies was assessed using systematic, reproducible, and quantitative tools (Kmet and NHMRC) concluding that all the selected articles reached a valid level of evidence. The literature search gathered data from various sources, ranging from double-blind randomised control trials to systematic reviews focused on changes occurring in swallowing physiology caused by thickened fluids. Main results suggest that increasing bolus viscosity (a) results in increased safety of swallowing, (b) also results in increased amounts of oral and/or pharyngeal residue which may result in post-swallow airway invasion, (c) impacts the physiology with increased lingual pressure patterns, no major changes in impaired

Intravenous digital subtraction angiography of the lower limbs combined with field movement (2-field DSA)

International Nuclear Information System (INIS)

Fritschy, P.; Terrier, F.

1988-01-01

We evaluated a bolus-chase technique designed to reduce the volume of contrast material and to shorten examination time during intravenous digital subtraction angiography (IV-DSA) of the lower limbs. With this technique, after a single injection of contrast material, two contiguous fields can be sequentially imaged (two-field DAS) using a step translated X-ray tube. 67 patients with peripheral vascular disease were studied. All examinations provided diagnostic information, so that in no instance additional intra-arterial injections were required. With the two-field DSA only 3.49 injections were needed in the average for five fields examined in each patient, resulting in a 30% reduction of contrast agent used. (orig.) [de

Cost-effectiveness of once daily GLP-1 receptor agonist lixisenatide compared to bolus insulin both in combination with basal insulin for the treatment of patients with type 2 diabetes in Norway.

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Huetson, Pernilla; Palmer, James L; Levorsen, Andrée; Fournier, Marie; Germe, Maeva; McLeod, Euan

2015-01-01

Lixisenatide is a potent, selective and short-acting once daily prandial glucagon-like peptide-1 receptor agonist which lowers glycohemoglobin and body weight by clinically significant amounts in patients with type 2 diabetes treated with basal insulin, with limited risk of hypoglycemia. To assess the cost-effectiveness of lixisenatide versus bolus insulin, both in combination with basal insulin, in patients with type 2 diabetes in Norway. The IMS CORE Diabetes Model, a non-product-specific and validated simulation model, was used to make clinical and cost projections. Transition probabilities, risk adjustments and the progression of complication risk factors were derived from the UK Prospective Diabetes Study, supplemented with Norwegian data. Patients were assumed to receive combination treatment with basal insulin, lixisenatide or bolus insulin therapy for 3 years, followed by intensification of a basal-bolus insulin regimen for their remaining lifetime. Simulated healthcare costs, taken from the public payer perspective, were derived from microcosting and diagnosis related groups, discounted at 4% per annum and reported in Norwegian krone (NOK). Productivity costs were also captured based on extractions from the Norwegian Labor and Welfare Administration. Health state utilities were derived from a systematic literature review. Sensitivity and scenario analyses were performed. Lixisenatide in combination with basal insulin was associated with increased quality-adjusted life years (QALYs) and reduced lifetime healthcare costs compared to bolus insulin in combination with basal insulin in patients with Type 2 diabetes, and can be considered dominant. The net monetary benefit of lixisenatide versus bolus insulin was NOK 39,369 per patient. Results were sensitive to discounting, the application of excess body weight associated disutility and uncertainty surrounding the changes in HbA1c. Lixisenatide may be considered an economically efficient therapy in combination

Radiotherapy in differentiated thyroid cancer: Optimal dose distribution using a wax bolus

International Nuclear Information System (INIS)

Mayer, R.; Stucklschweiger, G.; Oechs, A.; Pakish, B.; Hackl, A.; Preidler, K.; Szola, D.

1994-01-01

The study includes 53 patients with differentiated thyroid cancer, who underwent surgical and radioiodine therapy as well as hormone therapy. Postoperative radiotherapy was performed in all patients in 'mini-mantle-technique' with parallel opposed fields, followed by an anterior boost-field with electrons up to 60-64 Gy, using a wax bolus for optimal dose distribution in the target volume sparing out the spinal cord as much as possible. The dose to the spinal cord did not exceed 44 Gy in any case. The study shows that radiotherapy with doses up to 60-64 Gy plays an important role in postsurgical therapeutic management. Therefore nonradical surgery is a less important prognostic factor for survival and local recurrence in patients with differentiated thyroid cancer than histological diagnosis in combination with age and lymph node involvement

Closed-loop double-vasopressor automated system vs manual bolus vasopressor to treat hypotension during spinal anaesthesia for caesarean section: a randomised controlled trial.

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Sng, B L; Tan, H S; Sia, A T H

2014-01-01

Hypotension necessitating vasopressor administration occurs commonly during caesarean section under spinal anaesthesia. We developed a novel vasopressor delivery system that automatically administers phenylephrine or ephedrine based on continuous non-invasive arterial pressure monitoring. A phenylephrine bolus of 50 μg was given at 30-s intervals when systolic blood pressure fell manual boluses of either phenylephrine 100 μg or ephedrine 8 mg, administered at 1-min intervals based on the same thresholds for systolic pressure and heart rate. This randomised, controlled, double-blinded trial involved 213 healthy women who underwent elective caesarean delivery under spinal anaesthesia using 11 mg hyperbaric bupivacaine with 15 μg fentanyl and 100 μg morphine. The automated vasopressor group had better systolic pressure control, with 37/106 (34.9%) having any beat-to-beat systolic pressure reading 120% of baseline, with 8/106 (7.5%) in the automated vasopressor group vs 14/107 (13.1%) in the control group, or total dose of vasopressors. The automated vasopressor group had lower median absolute performance error of 8.5% vs control of 9.8% (p = 0.013), and reduced incidence of nausea (1/106 (0.9%) vs 11/107 (10.3%), p = 0.005). Neonatal umbilical cord pH, umbilical lactate and Apgar scores were similar. Hence, our system afforded better control of maternal blood pressure and reduced nausea with no increase in reactive hypertension when compared with manual boluses. © 2013 The Association of Anaesthetists of Great Britain and Ireland.

Comparison of bolus and continuous infusion of esmolol on hemodynamic response to laryngoscopy, endotracheal intubation and sternotomy in coronary artery bypass graft

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Esra Mercanooglu Efe

2014-07-01

Full Text Available BACKGROUND AND OBJECTIVE: The aim of this randomized, prospective and double blinded study is to investigate effects of different esmolol use on hemodynamic response of laryngoscopy, endotracheal intubation and sternotomy in coronary artery bypass graft surgery. METHODS: After approval of local ethics committee and patients' written informed consent, 45 patients were randomized into three groups equally. In Infusion Group; from 10 min before intubation up to 5th minute after sternotomy, 0.5 mg/kg/min esmolol infusion, in Bolus Group; 2 min before intubation and sternotomy 1.5 mg/kg esmolol IV bolus and in Control Group; %0.9 NaCl was administered. All demographic parameters were recorded. Heart rate and blood pressure were recorded before infusion up to anesthesia induction in every minute, during endotracheal intubation, every minute for 10 minutes after endotracheal intubation and before, during and after sternotomy at first and fifth minutes. RESULTS: While area under curve (AUC (SAP × time was being found more in Group B and C than Group I, AUC (SAP × T int and T st and AUC (SAP × T2 was found more in Group B and C than Group I (p < 0.05. Moreover AUC (HR × T st was found less in Group B than Group C but no significant difference was found between Group B and Group I. CONCLUSION: This study highlights that esmolol infusion is more effective than esmolol bolus administration on controlling systolic arterial pressure during endotracheal intubation and sternotomy in CABG surgery.

A randomized phase III multicenter trial comparing irinotecan in combination with the Nordic bolus 5-FU and folinic acid schedule or the bolus/infused de Gramont schedule (Lv5FU2) in patients with metastatic colorectal cancer

DEFF Research Database (Denmark)

Glimelius, B; Sørbye, H; Balteskard, L

2008-01-01

not differ (4% versus 6%, P = 0.3). Grade 3/4 neutropenia (11% versus 5%, P = 0.01) and grade 2 alopecia (18% versus 9%, P = 0.002) were more common in the FLIRI group. The 60-day mortality was 2.4% versus 2.1%. CONCLUSIONS: Irinotecan with the bolus Nordic schedule (FLIRI) is a convenient treatment with PFS...... and OS comparable to irinotecan with the Lv5FU2 schedule. Neutropenia and alopecia are more prevalent, but both regimens are equally well tolerated....

Identificação de Paspalum notatum fluegge e Axonopus affinis chase através da análise de fragmentos foliares Identification of Paspalum notatum fluegge and Axonopus affinis chase through leaf fragments analysis

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Maria Cláudia Lopes Nogueira

1999-03-01

Full Text Available Este trabalho teve como objetivo a caracterização e identificação de fragmentos foliares de Paspalum notatum Fluegge e Axonopus affinis Chase, como forma de subsidiar projetos de avaliação da dieta de animais fistulados. Para a caracterização das espécies, foram feitas várias coletas de folhas em áreas de pastagem natural do Campus da Universidade Federal de Santa Maria (RS, de maio de 1992 a junho de 1993. A diferenciação das espécies foi baseada no padrão de nervação, presença de pêlos e características do ápice e bordo foliar, observadas com auxílio de estereomicroscópio. A habilidade de um observador em identificar fragmentos das duas espécies numa mistura e a eficácia dos descritores foliares mencionados foram testadas através de análise estatística. Desta forma, foi constatado que o padrão de nervação é o melhor critério de diferenciação e que A. affinis difere de P. notatum, basicamente, pelo ápice foliar obtuso e pela presença de nervuras quaternárias. A análise estatística confirmou a capacidade do observador em reconhecer fragmentos das duas espécies.This research aimed at the characterization and identification of leaves, fragments of Paspalum notatum Fluegge and Axonopus affinis Chase, for future studies of diet evaluation of fistuleted animals. For the species characterization, several collections of leaves were made in native pasture areas at the UFSM Campus (Santa Maria, RS from May, 1992 to June, 1993. The differentiation of the species was based on the leave’s venation pattern, hair presence, leaf border and apex features, observed with a stereomicroscope. The obverver’s ability to identify the two species of leaves in a misture were tested with statistical analysis. It was observed that the venation pattern is the best characterization criteria and that A. affinis differs from P. notatum mainly by the obtuse leaf apex and by the quaternary vein presence. The statistical analysis

Methods of bolusing the tracheostomy stoma

International Nuclear Information System (INIS)

Beitler, Jonathan J.; Yaparpalvi, Ravindra; Biancia, Cesar Della; Fontenla, Doracy P.

2001-01-01

Purpose: The tracheostomy stoma is a potential site of recurrence for patients who have subglottic cancer or subglottic spread of cancer. In these patients, it is important that the anterior supraclavicular field does not underdose the posterior wall of the tracheostomy stoma when using a 6-MV anterior photon field. Conventionally, this problem is surmounted with placement of a plastic tracheostomy tube, which is uncomfortable for the patient, potentially traumatic, and can interfere with vocalization via a tracheal esophageal puncture. Our study was designed to investigate the dosimetry of this region and see if alternate methods would be effective. Methods and Materials: A phantom was constructed using a No. 6 tracheostomy tube as the model for the tracheostomy curvature and size. Using the water-equivalent phantom, film dosimetry, and films oriented parallel to the en face field, we investigated the dose at the depth of the surface of the posterior wall of the phantom's tracheostomy stoma. Dose was measured both in space and at the tissue interface by scanning points of interest both horizontally and vertically. We measured doses with a No. 6 and No. 8 plastic tracheostomy tube, either 0.5 cm and 1.0 cm of bolus (1-cm airhole) with no tracheostomy tube, as well as 0.3 cm and 0.6 cm tissue-equivalent Aquaplast (Med-Tec Co., Orange City, Iowa) over the tracheostomy. Dosimetry at the posterior interface was confirmed using thermoluminescent dosimeters. Results: Three mm and 6 mm of Aquaplast produced a posterior tracheal dose of 93% and 100%. Conclusion: There is no need for these patients to wear a temporary plastic tracheostomy tube during their external radiation therapy. Aquaplast should allow better position reproducibility, reduce trauma, not interfere with patient respiratory efforts, and be compatible with vocalization via a tracheal esophageal puncture

The Efficacy of Programmed Intermittent Epidural Bolus for Postoperative Analgesia after Open Gynecological Surgery: A Randomized Double-Blinded Study

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Shiho Satomi

2018-01-01

Full Text Available Background. It is well known that the programmed intermittent epidural bolus (PIEB technique effectively provides epidural anesthesia in labor. This randomized double-blind trial compared the postoperative analgesic efficacy of PIEB with that of continuous epidural infusion (CEI in patients undergoing gynecological surgery under combined general-epidural anesthesia. Methods. Patients undergoing open gynecological surgery under combined general-epidural anesthesia were randomized at a 1 : 1 ratio to receive PIEB or CEI. In the PIEB group, the pump delivered 4 mL ropivacaine 0.2% plus fentanyl 2 μg/mL every hour. In the CEI group, the pump delivered the same solution at a rate of 4 mL/h. In both groups, additional 4 mL boluses of ropivacaine 0.2% plus fentanyl 2 μg/mL were provided, when necessary, by patient-controlled epidural analgesia after surgery. The primary outcome was the total ropivacaine dose 40 hours after surgery. The secondary outcomes were the number of PCEA boluses and postoperative pain (evaluated on an 11-point numerical rating scale 3, 24, and 48 hours after surgery. Results. In total, 57 patients were randomized (n=28 and 29 in the PIEB and CEI groups, resp.. The two groups differ significantly in terms of the total ropivacaine dose 40 hours after surgery (mean (standard deviation: 155.38 (4.55 versus 159.73 (7.87 mL, P=0.016. Compared to the CEI group, the PIEB group had significantly lower numerical rating scale scores 3 hours (median [lower–upper quartiles]: 0 [0–0.5] versus 3 [0–5.5], P=0.002, 24 hours (1 [0–2] versus 3 [1–4], P=0.003, and 48 hours (1 [0–2] versus 2 [2–3.5], P=0.002 after surgery. Conclusion. PIEB was better than CEI in terms of providing postoperative analgesia after open gynecological surgery under combined general-epidural anesthesia.

Temperature profiles from expendable bathythermograph (XBT) casts from the USCGC CHASE in the North Atlantic Ocean in support of the Integrated Global Ocean Services System (IGOSS) from 1974-02-26 to 1974-03-01 (NODC Accession 7400264)

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National Oceanic and Atmospheric Administration, Department of Commerce — XBT data were collected from the USCGC CHASE in support of the Integrated Global Ocean Services System (IGOSS). Data were collected by the US Coast Guard from 26...

Comparison of treatment with continuous subcutaneous insulin infusion versus multiple daily insulin injections with bolus calculator in patients with type 1 diabetes.

Science.gov (United States)

Pérez-García, L; Goñi-Iriarte, M J; García-Mouriz, M

2015-01-01

A study of the glycemic control, quality of life, and fear and perception of hypoglycemia by comparing continuous subcutaneous insulin infusion (CSII) group with multiple daily inyections (MDI) with bolus calculator group. This is a retrospective cohort study with following up during the first 12 months that CSII group (n=30) begins the use of "bolus wizard" and the MDI-calculator (n=30) group begins the use of the bolus calculator (Accu-Chek(®) Aviva Expert). HbA1c (3, 6 and 12 months). Questionnaires used: EsDQOL (quality of life), FH-15 (fear of hypoglycemia), and Clarke (perception of hypoglycemia). T Student and nonparametric tests. The average reduction in HbA1c during the study was significantly higher in CSII group (-0.56±0.84%) compared with the MDI group (0.097±0.94%), P=.028. The average basal insulin dose was significantly higher in the MDI group (at baseline, 6 and 12 months). No significant differences were found between the 2 treatment groups after analyzing the EsDQOL, FH-15 and Clarke questionnaires. In the CSII group, perceived quality of life assessed by the EsDQOL questionnaire was found to be better at the end of the study than at the beginning of using the insulin pump. The average reduction in HbA1c was significantly higher in the CSII group. In the CSII group, perceived quality of life was better at the end of the study than at the beginning. Copyright © 2014 SEEN. Published by Elsevier España, S.L.U. All rights reserved.

Intravenous avidin chase improved localization of radiolabeled streptavidin in intraperitoneal xenograft pretargeted with biotinylated antibody

International Nuclear Information System (INIS)

Zhang Meili; Sakahara, Harumi; Yao Zhengsheng; Saga, Tsuneo; Nakamoto, Yuhi; Sato, Noriko; Nakada, Hiroshi; Yamashina, Ikuo; Konishi, Junji

1997-01-01

In the present study, we examined the effect of avidin administered intravenously (i.v.) on the biodistribution of radiolabeled streptavidin in mice bearing intraperitoneal (IP) xenografts pretargeted with biotinylated antibody. Tumors were established in nude mice by IP inoculation of LS180 human colon cancer cells. Monoclonal antibody MLS128, which recognizes Tn antigen on mucin, was biotinylated and injected IP into the IP tumor-bearing mice. Radioiodinated streptavidin was administered IP or i.v. 48 h after pretargeting of biotinylated antibody. Avidin was administered i.v. 30 min prior to streptavidin injection. The localization of radioiodinated streptavidin in the tumor pretargeted with biotinylated antibody was significantly higher than that without pretargeting and that of radioiodinated MLS128 by the one-step method. Avidin administration significantly accelerated the clearance of radioiodinated streptavidin in blood and other normal tissues and increased the tumor-to-blood radioactivity ratio regardless of administration route of streptavidin. The i.v. avidin chase improved tumor localization of radiolabeled streptavidin in the IP xenografts pretargeted with biotinylated antibody

Factors predicting incremental administration of antihypertensive boluses during deep brain stimulator placement for Parkinson's disease.

Science.gov (United States)

Rajan, Shobana; Deogaonkar, Milind; Kaw, Roop; Nada, Eman Ms; Hernandez, Adrian V; Ebrahim, Zeyd; Avitsian, Rafi

2014-10-01

Hypertension is common in deep brain stimulator (DBS) placement predisposing to intracranial hemorrhage. This retrospective review evaluates factors predicting incremental antihypertensive use intraoperatively. Medical records of Parkinson's disease (PD) patients undergoing DBS procedure between 2008-2011 were reviewed after Institutional Review Board approval. Anesthesia medication, preoperative levodopa dose, age, preoperative use of antihypertensive medications, diabetes mellitus, anxiety, motor part of the Unified Parkinson's Disease Rating Scale score and PD duration were collected. Univariate and multivariate analysis was done between each patient characteristic and the number of antihypertensive boluses. From the 136 patients included 60 were hypertensive, of whom 32 were on angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB), told to hold on the morning of surgery. Antihypertensive medications were given to 130 patients intraoperatively. Age (relative risk [RR] 1.01; 95% confidence interval [CI] 1.00-1.02; p=0.005), high Joint National Committee (JNC) class (p10 years (RR 1.2; 95%CI 1.1-1.3; p=0.001) were independent predictors for antihypertensive use. No difference was noted in the mean dose of levodopa (p=0.1) and levodopa equivalent dose (p=0.4) between the low (I/II) and high severity (III/IV) JNC groups. Addition of dexmedetomidine to propofol did not influence antihypertensive boluses required (p=0.38). Intraoperative hypertension during DBS surgery is associated with higher age group, hypertensive, diabetic patients and longer duration of PD. Withholding ACEI or ARB is an independent predictor of hypertension requiring more aggressive therapy. Levodopa withdrawal and choice of anesthetic agent is not associated with higher intraoperative antihypertensive medications. Copyright © 2014 Elsevier Ltd. All rights reserved.

Radiation dermatitis caused by a bolus effect from an abdominal compression device

International Nuclear Information System (INIS)

Connor, Michael; Wei, Randy L.; Yu, Suhong; Sehgal, Varun; Klempner, Samuel J.; Daroui, Parima

2016-01-01

American Association of Physicists in Medicine (AAPM) Task Group 176 evaluated the dosimetric effects caused by couch tops and immobilization devices. The report analyzed the extensive physics-based literature on couch tops, stereotactic body radiation therapy (SBRT) frames, and body immobilization bags, while noting the scarcity of clinical reports of skin toxicity because of external devices. Here, we present a clinical case report of grade 1 abdominal skin toxicity owing to an abdominal compression device. We discuss the dosimetric implications of the utilized treatment plan as well as post hoc alternative plans and quantify differences in attenuation and skin dose/build-up between the device, a lower-density alternative device, and an open field. The description of the case includes a 66-year-old male with HER2 amplified poorly differentiated distal esophageal adenocarcinoma treated with neoadjuvant chemo-radiation and the use of an abdominal compression device. Radiation was delivered using volumetric modulated arc therapy (VMAT) with 2 arcs using abdominal compression and image guidance. The total dose was 50.4 Gy delivered over 40 elapsed days. With 2 fractions remaining, the patient developed dermatitis in the area of the compression device. The original treatment plan did not include a contour of the device. Alternative post hoc treatment plans were generated, one to contour the device and a second with anterior avoidance. In conclusion, replanning with the device contoured revealed the bolus effect. The skin dose increased from 27 to 36 Gy. planned target volume (PTV) coverage at 45 Gy was reduced to 76.5% from 95.8%. The second VMAT treatment plan with an anterior avoidance sector and more oblique beam angles maintained PTV coverage and spared the anterior wall, however at the expense of substantially increased dose to lung. This case report provides an important reminder of the bolus effect from external devices such as abdominal compression. Special

Radiation dermatitis caused by a bolus effect from an abdominal compression device

Energy Technology Data Exchange (ETDEWEB)

Connor, Michael; Wei, Randy L.; Yu, Suhong; Sehgal, Varun [Department of Radiation Oncology, University of California, Irvine Medical Center, Orange, CA (United States); Klempner, Samuel J. [Department of Medicine, Division of Hematology/Oncology, University of California, Orange, CA (United States); Daroui, Parima, E-mail: pdaroui@uci.edu [Department of Radiation Oncology, University of California, Irvine Medical Center, Orange, CA (United States)

2016-10-01

American Association of Physicists in Medicine (AAPM) Task Group 176 evaluated the dosimetric effects caused by couch tops and immobilization devices. The report analyzed the extensive physics-based literature on couch tops, stereotactic body radiation therapy (SBRT) frames, and body immobilization bags, while noting the scarcity of clinical reports of skin toxicity because of external devices. Here, we present a clinical case report of grade 1 abdominal skin toxicity owing to an abdominal compression device. We discuss the dosimetric implications of the utilized treatment plan as well as post hoc alternative plans and quantify differences in attenuation and skin dose/build-up between the device, a lower-density alternative device, and an open field. The description of the case includes a 66-year-old male with HER2 amplified poorly differentiated distal esophageal adenocarcinoma treated with neoadjuvant chemo-radiation and the use of an abdominal compression device. Radiation was delivered using volumetric modulated arc therapy (VMAT) with 2 arcs using abdominal compression and image guidance. The total dose was 50.4 Gy delivered over 40 elapsed days. With 2 fractions remaining, the patient developed dermatitis in the area of the compression device. The original treatment plan did not include a contour of the device. Alternative post hoc treatment plans were generated, one to contour the device and a second with anterior avoidance. In conclusion, replanning with the device contoured revealed the bolus effect. The skin dose increased from 27 to 36 Gy. planned target volume (PTV) coverage at 45 Gy was reduced to 76.5% from 95.8%. The second VMAT treatment plan with an anterior avoidance sector and more oblique beam angles maintained PTV coverage and spared the anterior wall, however at the expense of substantially increased dose to lung. This case report provides an important reminder of the bolus effect from external devices such as abdominal compression. Special

Comparison of /sup 133/Xe washout curves after bolus inhalation, perfusion, and equilibration

Energy Technology Data Exchange (ETDEWEB)

Devos, P; Demedts, M; Vandecruys, A; Cosemans, J; De Roo, M

1978-01-01

In 6 healthy subjects and 13 patients with chronic obstructive lung disease, /sup 133/Xe washout curves after bolus inhalation, perfusion and equilibration were compared, using a gamma camera and computerized data handling. In healthy subjects the washout after equilibration was significantly slower than after the two other procedures. As this phenomenon occurred at the basal zones, it was attributed to the presence of airway closure in some units. In patients, the three washouts were significantly different from each other. This indicated the existence of intraregional inhomogeneity in ventilation, perfusion and ventilation-perfusion ratio. Our conclusion is that comparison of these different washout methods yields valuable information not only on absolute values of pulmonary function but also on the intraregional distribution, which cannot be obtained by other examinations.

[Simultaneous determination of five effective components in Sijunzi bolus using high performance liquid chromatography-evaporation light scattering detection].

Science.gov (United States)

Li, Chunying; Zhang, Xiaojun

2010-01-01

A high performance liquid chromatographic (HPLC) method was developed for the simultaneous determination of lobetyolin, pachymic acid, glycyrrhizic acid, atractylenoide III and atractylenolide I in Sijunzi bolus. The separation was performed on an HIQ SIL C18 V column (250 mm x 4.6 mm, 5 microm) with 0.5% acetic acid-methanol as the mobile phase of gradient elution at a flow rate of 1.0 mL/min. The detection was performed with an evaporation light scattering detector (ELSD) and the sample volume was 10 microL. The temperature of drift tube and heating grade of nebulizer was respectively set at 55 degrees C and 60% at 0.2 MPa of pressure. Nitrogen gas was used as carrier gas. Under the optimized conditions, there were good linear relationships between the logarithm values of mass concentration and the peak areas of lobetyolin, pachymic acid, glycyrrhizic acid, atractylenoide III and atractylenolide I in the ranges of 0.076 - 1.21, 0.048 -0.76, 0.153 - 2.45, 0.045 - 0.72 and 0.098 - 1.56 g/L, respectively. The recoveries of the five components were between 97.13% and 100.25%, the relative standard deviations (RSDs) were between 1.23% and 2.44%. This method is simple, rapid, accurate and suitable for the quality control of Sijunzi bolus.

Study protocol. ECSSIT - Elective Caesarean Section Syntocinon Infusion Trial. A multi-centre randomised controlled trial of oxytocin (Syntocinon) 5 IU bolus and placebo infusion versus oxytocin 5 IU bolus and 40 IU infusion for the control of blood loss at elective caesarean section.

LENUS (Irish Health Repository)

Murphy, Deirdre J

2012-02-01

BACKGROUND: Caesarean section is one of the most commonly performed major operations in women throughout the world. Rates are escalating, with studies from the United States of America, the United Kingdom, China and the Republic of Ireland reporting rates between 20% and 25%. Operative morbidity includes haemorrhage, anaemia, blood transfusion and in severe cases, maternal death. The value of routine oxytocics in the third stage of vaginal birth has been well established and it has been assumed that these benefits apply to caesarean delivery as well. A slow bolus dose of oxytocin is recommended following delivery of the baby at caesarean section. Some clinicians use an additional infusion of oxytocin for a further period following the procedure. Intravenous oxytocin has a very short half-life (4-10 minutes) therefore the potential advantage of an oxytocin infusion is that it maintains uterine contractility throughout the surgical procedure and immediate postpartum period, when most primary haemorrhages occur. The few trials to date addressing the optimal approach to preventing haemorrhage at caesarean section have been under-powered to evaluate clinically important outcomes. There has been no trial to date comparing the use of an intravenous slow bolus of oxytocin versus an oxytocin bolus and infusion. METHODS AND DESIGN: A multi-centre randomised controlled trial is proposed. The study will take place in five large maternity units in Ireland with collaboration between academics and clinicians in the disciplines of obstetrics and anaesthetics. It will involve 2000 women undergoing elective caesarean section after 36 weeks gestation. The main outcome measure will be major haemorrhage (blood loss >1000 ml). A study involving 2000 women will have 80% power to detect a 36% relative change in the risk of major haemorrhage with two-sided 5% alpha. DISCUSSION: It is both important and timely that we evaluate the optimal approach to the management of the third stage at

Study protocol. ECSSIT - Elective Caesarean Section Syntocinon Infusion Trial. A multi-centre randomised controlled trial of oxytocin (Syntocinon) 5 IU bolus and placebo infusion versus oxytocin 5 IU bolus and 40 IU infusion for the control of blood loss at elective caesarean section.

LENUS (Irish Health Repository)

Murphy, Deirdre J

2009-01-01

BACKGROUND: Caesarean section is one of the most commonly performed major operations in women throughout the world. Rates are escalating, with studies from the United States of America, the United Kingdom, China and the Republic of Ireland reporting rates between 20% and 25%. Operative morbidity includes haemorrhage, anaemia, blood transfusion and in severe cases, maternal death. The value of routine oxytocics in the third stage of vaginal birth has been well established and it has been assumed that these benefits apply to caesarean delivery as well. A slow bolus dose of oxytocin is recommended following delivery of the baby at caesarean section. Some clinicians use an additional infusion of oxytocin for a further period following the procedure. Intravenous oxytocin has a very short half-life (4-10 minutes) therefore the potential advantage of an oxytocin infusion is that it maintains uterine contractility throughout the surgical procedure and immediate postpartum period, when most primary haemorrhages occur. The few trials to date addressing the optimal approach to preventing haemorrhage at caesarean section have been under-powered to evaluate clinically important outcomes. There has been no trial to date comparing the use of an intravenous slow bolus of oxytocin versus an oxytocin bolus and infusion. METHODS AND DESIGN: A multi-centre randomised controlled trial is proposed. The study will take place in five large maternity units in Ireland with collaboration between academics and clinicians in the disciplines of obstetrics and anaesthetics. It will involve 2000 women undergoing elective caesarean section after 36 weeks gestation. The main outcome measure will be major haemorrhage (blood loss >1000 ml). A study involving 2000 women will have 80% power to detect a 36% relative change in the risk of major haemorrhage with two-sided 5% alpha. DISCUSSION: It is both important and timely that we evaluate the optimal approach to the management of the third stage at

Characterization of the Photon Counting CHASE Jr., Chip Built in a 40-nm CMOS Process With a Charge Sharing Correction Algorithm Using a Collimated X-Ray Beam

Energy Technology Data Exchange (ETDEWEB)

Krzyżanowska, A. [AGH-UST, Cracow; Deptuch, G. W. [Fermilab; Maj, P. [AGH-UST, Cracow; Gryboś, P. [AGH-UST, Cracow; Szczygieł, R. [AGH-UST, Cracow

2017-08-01

This paper presents the detailed characterization of a single photon counting chip, named CHASE Jr., built in a CMOS 40-nm process, operating with synchrotron radiation. The chip utilizes an on-chip implementation of the C8P1 algorithm. The algorithm eliminates the charge sharing related uncertainties, namely, the dependence of the number of registered photons on the discriminator’s threshold, set for monochromatic irradiation, and errors in the assignment of an event to a certain pixel. The article presents a short description of the algorithm as well as the architecture of the CHASE Jr., chip. The analog and digital functionalities, allowing for proper operation of the C8P1 algorithm are described, namely, an offset correction for two discriminators independently, two-stage gain correction, and different operation modes of the digital blocks. The results of tests of the C8P1 operation are presented for the chip bump bonded to a silicon sensor and exposed to the 3.5- μm -wide pencil beam of 8-keV photons of synchrotron radiation. It was studied how sensitive the algorithm performance is to the chip settings, as well as the uniformity of parameters of the analog front-end blocks. Presented results prove that the C8P1 algorithm enables counting all photons hitting the detector in between readout channels and retrieving the actual photon energy.

"Sniffer"—a novel tool for chasing vehicles and measuring traffic pollutants

Science.gov (United States)

Pirjola, L.; Parviainen, H.; Hussein, T.; Valli, A.; Hämeri, K.; Aaalto, P.; Virtanen, A.; Keskinen, J.; Pakkanen, T. A.; Mäkelä, T.; Hillamo, R. E.

To measure traffic pollutants with high temporal and spatial resolution under real conditions a mobile laboratory was designed and built in Helsinki Polytechnic in close co-operation with the University of Helsinki. The equipment of the van provides gas phase measurements of CO and NO x, number size distribution measurements of fine and ultrafine particles by an electrical low pressure impactor, an ultrafine condensation particle counter and a scanning mobility particle sizer. Two inlet systems, one above the windshield and the other above the bumper, enable chasing of different type of vehicles. Also, meteorological and geographical parameters are recorded. This paper introduces the construction and technical details of the van, and presents data from the measurements performed during an LIPIKA campaign on the highway in Helsinki. Approximately 90% of the total particle number concentration was due to particles smaller than 50 nm on the highway in Helsinki. The peak concentrations exceeded often 200,000 particles cm -3 and reached sometimes a value of 10 6 cm -3. Typical size distribution of fine particles possessed bimodal structure with the modal mean diameters of 15-20 nm and ˜150 nm. Atmospheric dispersion of traffic pollutions were measured by moving away from the highway along the wind direction. At a distance of 120-140 m from the source the concentrations were diluted to one-tenth from the values at 9 m from the source.

Intratracheal Milrinone Bolus Administration During Acute Right Ventricular Dysfunction After Cardiopulmonary Bypass.

Science.gov (United States)

Gebhard, Caroline Eva; Desjardins, Georges; Gebhard, Cathérine; Gavra, Paul; Denault, André Y

2017-04-01

To evaluate intratracheal milrinone (tMil) administration for rapid treatment of right ventricular (RV) dysfunction as a novel route after cardiopulmonary bypass. Retrospective analysis. Single-center study. The study comprised 7 patients undergoing cardiac surgery who exhibited acute RV dysfunction after cardiopulmonary bypass. After difficult weaning caused by cardiopulmonary bypass-induced acute RV dysfunction, milrinone was administered as a 5-mg bolus inside the endotracheal tube. RV function improvement, as indicated by decreasing pulmonary artery pressure and changes of RV waveforms, was observed in all 7 patients. Adverse effects of tMil included dynamic RV outflow tract obstruction (2 patients) and a decrease in systemic mean arterial pressure (1 patient). tMil may be an effective, rapid, and easily applicable therapeutic alternative to inhaled milrinone for the treatment of acute RV failure during cardiac surgery. However, sufficiently powered clinical trials are needed to confirm these findings. Copyright © 2017 Elsevier Inc. All rights reserved.

The Effect of Rheological Properties of Foods on Bolus Characteristics After Mastication

Science.gov (United States)

Hwang, Junah; Bae, Jung Hyun; Kang, Si Hyun; Seo, Kyung Mook; Kim, Byong Ki; Lee, Sook Young

2012-01-01

Objective To evaluate the effects of physical properties of foods on the changes of viscosity and mass as well as the particle size distribution after mastication. Method Twenty subjects with no masticatory disorders were recruited. Six grams of four solid foods of different textures (banana, tofu, cooked-rice, cookie) were provided, and the viscosity and mass after 10, 20, and 30 cycles of mastication and just before swallowing were measured. The physical properties of foods, such as hardness, cohesiveness, and adhesiveness, were measured with a texture analyzer. Wet sieving and laser diffraction were used to determine the distribution of food particle size. Results When we measured the physical characteristics of foods, the cookie was the hardest food, and the banana exhibited marked adhesiveness. Tofu and cooked-rice exhibited a highly cohesive nature. As the number of mastication cycles increased, the masses of all foods were significantly increased (pmastication (pmastication process and food bolus formation were affected by the physical properties of the food. PMID:23342309

Ultrasound-mediated gene delivery of naked plasmid DNA in skeletal muscles: a case for bolus injections.

Science.gov (United States)

Sanches, Pedro Gomes; Mühlmeister, Mareike; Seip, Ralf; Kaijzel, Eric; Löwik, Clemens; Böhmer, Marcel; Tiemann, Klaus; Grüll, Holger

2014-12-10

Localized gene delivery has many potential clinical applications. However, the nucleic acids (e.g. pDNA and siRNA) are incapable of passively crossing the endothelium, cell membranes and other biological barriers which must be crossed to reach their intracellular targets. A possible solution is the use of ultrasound to burst circulating microbubbles inducing transient permeabilization of surrounding tissues which mediates nucleic acid extravasation and cellular uptake. In this study we report on an optimization of the ultrasound gene delivery technique. Naked pDNA (200 μg) encoding luciferase and SonoVue® microbubbles were co-injected intravenously in mice. The hindlimb skeletal muscles were exposed to ultrasound from a non-focused transducer (1 MHz, 1.25 MPa, PRI 30s) and injection protocols and total amounts as well as ultrasound parameters were systemically varied. Gene expression was quantified relative to a control using a bioluminescence camera system at day 7 after sonication. Bioluminescence ratios in sonicated/control muscles of up to 101× were obtained. In conclusion, we were able to specifically deliver genetic material to the selected skeletal muscles and overall, the use of bolus injections and high microbubble numbers resulted in increased gene expression reflected by stronger bioluminescence signals. Based on our data, bolus injections seem to be required in order to achieve transient highly concentrated levels of nucleic acids and microbubbles at the tissue of interest which upon ultrasound exposure should lead to increased levels of gene delivery. Thus, ultrasound mediated gene delivery is a promising technique for the clinical translation of localized drug delivery. Copyright © 2014 Elsevier B.V. All rights reserved.

Continuous Transversus Abdominis Plane Nerve Blocks: Does Varying Local Anesthetic Delivery Method-Automatic Repeated Bolus Versus Continuous Basal Infusion-Influence the Extent of Sensation to Cold?: A Randomized, Triple-Masked, Crossover Study in Volunteers.

Science.gov (United States)

Khatibi, Bahareh; Said, Engy T; Sztain, Jacklynn F; Monahan, Amanda M; Gabriel, Rodney A; Furnish, Timothy J; Tran, Johnathan T; Donohue, Michael C; Ilfeld, Brian M

2017-04-01

It remains unknown whether continuous or scheduled intermittent bolus local anesthetic administration is preferable for transversus abdominis plane (TAP) catheters. We therefore tested the hypothesis that when using TAP catheters, providing local anesthetic in repeated bolus doses increases the cephalad-caudad cutaneous effects compared with a basal-only infusion. Bilateral TAP catheters (posterior approach) were inserted in 24 healthy volunteers followed by ropivacaine 2 mg/mL administration for a total of 6 hours. The right side was randomly assigned to either a basal infusion (8 mL/h) or bolus doses (24 mL administered every 3 hours for a total of 2 bolus doses) in a double-masked manner. The left side received the alternate treatment. The primary end point was the extent of sensory deficit as measured by cool roller along the axillary line at hour 6 (6 hours after the local anesthetic administration was initiated). Secondary end points included the extent of sensory deficit as measured by cool roller and Von Frey filaments along the axillary line and along a transverse line at the level of the anterior superior iliac spine at hours 0 to 6. Although there were statistically significant differences between treatments within the earlier part of the administration period, by hour 6 the difference in extent of sensory deficit to cold failed to reach statistical significance along the axillary line (mean = 0.9 cm; SD = 6.8; 95% confidence interval -2.0 to 3.8; P = .515) and transverse line (mean = 2.5 cm; SD = 10.1; 95% confidence interval -1.8 to 6.8; P = .244). Although the difference between treatments was statistically significant at various early time points for the horizontal, vertical, and estimated area measurements of both cold and mechanical pressure sensory deficits, no comparison remained statistically significant by hour 6. No evidence was found in this study involving healthy volunteers to support the hypothesis that changing the local anesthetic

In vivo measurement of haloperidol affinity to dopamine D2/D3 receptors by [123I]IBZM and single photon emission computed tomography

DEFF Research Database (Denmark)

Videbaek, C; Toska, K; Friberg, L

2001-01-01

This study examines the feasibility of a steady-state bolus-integration method with the dopamine D2/D3 receptor single photon emission computer tomography (SPECT) tracer, [123I]IBZM, for determination of in vivo affinity of haloperidol. The nonspecific binding of [123I]IBZM was examined in the rat...... brain by infusion of haloperidol to plasma levels approximately 100 times the Kd level in man. In humans, Kd for haloperidol binding was measured in four healthy volunteers that were examined twice: once with partial dopamine D2/D3 receptor blockade obtained by a scheduled infusion of unlabeled...... haloperidol (0.7 mg total dosage), and once in an unblocked state. Blood sampling and SPECT were performed intermittently during 6 hours after intravenous [123I]IBZM bolus injection. Plasma [123I]IBZM was determined by octane extraction. Plasma haloperidol was determined by a radioimmunoassay, and plasma...

Arterioportal shunts on dynamic computed tomography

International Nuclear Information System (INIS)

Nakayama, T.; Hiyama, Y.; Ohnishi, K.; Tsuchiya, S.; Kohno, K.; Nakajima, Y.; Okuda, K.

1983-01-01

Thirty-two patients, 20 with hepatocelluar carcinoma and 12 with liver cirrhosis, were examined by dynamic computed tomography (CT) using intravenous bolus injection of contrast medium and by celiac angiography. Dynamic CT disclosed arterioportal shunting in four cases of hepatocellular carcinoma and in one of cirrhosis. In three of the former, the arterioportal shunt was adjacent to a mass lesion on CT, suggesting tumor invasion into the portal branch. In one with hepatocellular carcinoma, the shunt was remote from the mass. In the case with cirrhosis, there was no mass. In these last two cases, the shunt might have been caused by prior percutaneous needle puncture. In another case of hepatocellular carcinoma, celiac angiography but not CT demonstrated an arterioportal shunt. Thus, dynamic CT was diagnostic in five of six cases of arteriographically demonstrated arterioportal shunts

Cerebral hemodynamic changes measured by gradient-echo or spin-echo bolus tracking and its correlation to changes in ICA blood flow measured by phase-mapping MRI

DEFF Research Database (Denmark)

Marstrand, J.R.; Rostrup, Egill; Garde, Ellen

2001-01-01

Changes in cerebral blood flow (CBF) induced by Acetazolamide (ACZ) were measured using dynamic susceptibility contrast MRI (DSC-MRI) with both spin echo (SE) EPI and gradient echo (GE) EPI, and related to changes in internal carotid artery (ICA) flow measured by phase-mapping. Also examined...... was the effect of repeated bolus injections. CBF, cerebral blood volume (CBV), and mean transit time (MTT) were calculated by singular value decomposition (SVD) and by deconvolution using an exponential function as kernel. The results showed no dependency on calculation method. GE-EPI measured a significant...... increase in CBF and CBV in response to ACZ, while SE-EPI measured a significant increase in CBV and MTT. CBV and MTT change measured by SE-EPI was sensitive to previous bolus injections. There was a significant linear relation between change in CBF measured by GE-EPI and change in ICA flow. In conclusion...

Evaluation of the effect of bolus administration of 50% dextrose solution on measures of electrolyte and energy balance in postpartum dairy cows.

Science.gov (United States)

Wagner, Sarah A; Schimek, Daniel E

2010-09-01

To determine the effect of IV administration of a bolus of 50% dextrose solution on electrolyte and energy balance and effect of blood collection site on serum electrolyte values in postparturient dairy cows. 24 clinically normal multiparous cows. A bolus of 50% dextrose solution (0.5 L [n=8 cows]), 50% dextrose solution (1.0 L [8]), or saline (0.9% NaCl) solution (1.0 L, control treatment [8]) was administered via jugular venipuncture 5 to 10 days after parturition. Pretreatment and posttreatment blood samples were analyzed for concentrations of calcium, magnesium, phosphorus, potassium, glucose, insulin, beta-hydroxybutyric acid (BHBA), and nonesterified fatty acids. Coccygeal vessel and jugular vein blood samples were obtained prior to treatment, and electrolyte concentrations were compared. Treatment with 50% dextrose decreased phosphorus concentration in serum, compared with the control treatment. Suppression of BHBA and nonesterified fatty acid concentrations following dextrose treatment lasted for dextrose solution may be at risk for hypophosphatemia, and 1 treatment with 0.5 or 1 L of 50% dextrose solution is unlikely to prevent or resolve acetonemia (ketosis). The risk of hypophosphatemia may be underestimated when coccygeal vessel blood samples are used for diagnosis.

Prolonged infusion versus intermittent boluses of β-lactam antibiotics for treatment of acute infections: a meta-analysis.

Science.gov (United States)

Teo, Jocelyn; Liew, Yixin; Lee, Winnie; Kwa, Andrea Lay-Hoon

2014-05-01

The clinical advantages of prolonged (extended/continuous) infusion remain controversial. Previous studies and reviews have failed to show consistent clinical benefits of extending the infusion time. This meta-analysis sought to determine whether prolonged β-lactam infusions were associated with a reduction in mortality and improvement in clinical success. A search of PubMed, EMBASE and The Cochrane Library for randomised controlled trials (RCTs) and observational studies comparing prolonged infusion with intermittent bolus administration of the same antibiotic in hospitalised adult patients was conducted. Primary outcomes evaluated were mortality and clinical success. A total of 29 studies with 2206 patients (18 RCTs and 11 observational studies) were included in the meta-analysis. Compared with intermittent boluses, use of prolonged infusion appeared to be associated with a significant reduction in mortality [pooled relative risk (RR) = 0.66, 95% confidence interval (CI) 0.53-0.83] and improvement in clinical success (RR = 1.12, 95% CI 1.03-1.21). Statistically significant benefit was supported by non-randomised studies (mortality, RR = 0.57, 95% CI 0.43-0.76; clinical success, RR = 1.34, 95% CI 1.02-1.76) but not by RCTs (mortality, RR = 0.83, 95% CI 0.57-1.21; clinical success, RR = 1.05, 95% CI 0.99-1.12). The positive results from observational studies, especially in the face of increasing antibiotic resistance, serve to justify the imperative need to conduct a large-scale, well-designed, multicentre RCT involving critically ill patients infected with high minimum inhibitory concentration pathogens to clearly substantiate this benefit. Copyright © 2014 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

A qualitative feasibility study to inform a randomised controlled trial of fluid bolus therapy in septic shock

Science.gov (United States)

O’Hara, Caitlin B; Canter, Ruth R; Mouncey, Paul R; Carter, Anjali; Jones, Nicola; Nadel, Simon; Peters, Mark J; Lyttle, Mark D; Harrison, David A; Rowan, Kathryn M; Inwald, David; Woolfall, Kerry

2018-01-01

Objective The Fluids in Shock (FiSh) Trial proposes to evaluate whether restrictive fluid bolus therapy (10 mL/kg) is more beneficial than current recommended practice (20 mL/kg) in the resuscitation of children with septic shock in the UK. This qualitative feasibility study aimed to explore acceptability of the FiSh Trial, including research without prior consent (RWPC), potential barriers to recruitment and participant information for a pilot trial. Design Qualitative interview study involving parents of children who had presented to a UK emergency department or been admitted to a paediatric intensive care unit with severe infection in the previous 3 years. Participants Twenty-one parents (seven bereaved) were interviewed 16 (median) months since their child’s hospital admission (range: 1–41). Results All parents said they would have provided consent for the use of their child’s data in the FiSh Trial. The majority were unfamiliar with RWPC, yet supported its use. Parents were initially concerned about the change from currently recommended treatment, yet were reassured by explanations of the current evidence base, fluid bolus therapy and monitoring procedures. Parents made recommendations about the timing of the research discussion and content of participant information. Bereaved parents stated that recruiters should not discuss research immediately after a child’s death, but supported a personalised postal ‘opt-out’ approach to consent. Conclusions Findings show that parents whose child has experienced severe infection supported the proposed FiSh Trial, including the use of RWPC. Parents’ views informed the development of the pilot trial protocol and site staff training. Trial registration number ISRCTN15244462—results. PMID:28847877

Perbandingan Efek Pemberian Norepinefrin Bolus Intravena dengan Norepinefrin Infus Kontinu dalam Tatalaksana Hipotensi, Laju Nadi, dan Nilai APGAR pada Seksio Sesarea dengan Anestesi Spinal

Directory of Open Access Journals (Sweden)

Fitri Sepviyanti Sumardi

2015-04-01

Full Text Available Vasopresors are commonly used for the treatment of hypotension in spinal anesthesia for cesarean section. This research aimed to compare intravenous bolus of norepinephrine to continuous infusion of norepinephrine effectiveness in hypotension management in caesarean section patient under spinal anesthesia and their effect on heart rate and APGAR Score, The experimental study was conducted in a double-blind randomized manner to 44 American Society of Anesthesiologist (ASA physical status II pregnant women undergoing cesarean section with spinal anesthesia in Dr. Hasan Sadikin General Hospital Bandung within the period of September to -November 2013. The Study subjects were grouped into two groups, the first group received 4 µg intravenous bolus of norepinephrine group (NB and and the second received 8 µg/minute continuous infusion of norepinephrine group (NK. Data were analyzed by t-test, Mann-Whitney test, chi-square and analysis of variance (ANOVA t-test with p0.05. Conclusion from this study is the administration of norepinephrine in both ways can be used for the treatment of hypotension of spinal anesthesia without affecting the heart rate and APGAR score

Visual processing in rapid-chase systems: Image processing, attention, and awareness

Directory of Open Access Journals (Sweden)

Thomas eSchmidt

2011-07-01

Full Text Available Visual stimuli can be classified so rapidly that their analysis may be based on a single sweep of feedforward processing through the visuomotor system. Behavioral criteria for feedforward processing can be evaluated in response priming tasks where speeded pointing or keypress responses are performed towards target stimuli which are preceded by prime stimuli. We apply this method to several classes of complex stimuli. 1 When participants classify natural images into animals or non-animals, the time course of their pointing responses indicates that prime and target signals remain strictly sequential throughout all processing stages, meeting stringent behavioral criteria for feedforward processing (rapid-chase criteria. 2 Such priming effects are boosted by selective visual attention for positions, shapes, and colors, in a way consistent with bottom-up enhancement of visuomotor processing, even when primes cannot be consciously identified. 3 Speeded processing of phobic images is observed in participants specifically fearful of spiders or snakes, suggesting enhancement of feedforward processing by long-term perceptual learning. 4 When the perceived brightness of primes in complex displays is altered by means of illumination or transparency illusions, priming effects in speeded keypress responses can systematically contradict subjective brightness judgments, such that one prime appears brighter than the other but activates motor responses as if it was darker. We propose that response priming captures the output of the first feedforward pass of visual signals through the visuomotor system, and that this output lacks some characteristic features of more elaborate, recurrent processing. This way, visuomotor measures may become dissociated from several aspects of conscious vision. We argue that "fast" visuomotor measures predominantly driven by feedforward processing should supplement "slow" psychophysical measures predominantly based on visual

MnDPDP enhancement in rabbit liver after intravenous bolus injection and slow infusion

International Nuclear Information System (INIS)

Thorstensen, Oe.; Isberg, B.; Jorulf, H.; Westman, L.; Svahn, U.; Venizelos, N.

1997-01-01

Purpose: To investigate the MR-enhancing effect of mangafodipir trisodium (MnDPDP, Teslascan) in the rabbit liver in relation to dose, mode of administration and imaging window. Material and Methods: MnDPDP was administered to 18 rabbits at a dose of 10 μmol/kg or 20 μmol/kg, as a bolus injection or infusion. MR imaging of the liver was performed at different time intervals. Results: Peak liver enhancement was typically observed 10-30 min after administration and the enhancement declined with a half-time of about 5 h. This pattern was observed in all sequences (SE 400/15, FLASH, and SE 132/10), with both doses and with both rates of administration. The peak enhancement was greater, though not significantly so after 20 μmol/kg than after 10 μmol/kg. A higher relative peak signal was observed with SE 132/10 than with FLASH or SE 400/15. (orig./AJ)

Study Protocol. ECSSIT – Elective Caesarean Section Syntocinon® Infusion Trial. A multi-centre randomised controlled trial of oxytocin (Syntocinon® 5 IU bolus and placebo infusion versus oxytocin 5 IU bolus and 40 IU infusion for the control of blood loss at elective caesarean section

Directory of Open Access Journals (Sweden)

Montgomery Alan A

2009-08-01

Full Text Available Abstract Background Caesarean section is one of the most commonly performed major operations in women throughout the world. Rates are escalating, with studies from the United States of America, the United Kingdom, China and the Republic of Ireland reporting rates between 20% and 25%. Operative morbidity includes haemorrhage, anaemia, blood transfusion and in severe cases, maternal death. The value of routine oxytocics in the third stage of vaginal birth has been well established and it has been assumed that these benefits apply to caesarean delivery as well. A slow bolus dose of oxytocin is recommended following delivery of the baby at caesarean section. Some clinicians use an additional infusion of oxytocin for a further period following the procedure. Intravenous oxytocin has a very short half-life (4–10 minutes therefore the potential advantage of an oxytocin infusion is that it maintains uterine contractility throughout the surgical procedure and immediate postpartum period, when most primary haemorrhages occur. The few trials to date addressing the optimal approach to preventing haemorrhage at caesarean section have been under-powered to evaluate clinically important outcomes. There has been no trial to date comparing the use of an intravenous slow bolus of oxytocin versus an oxytocin bolus and infusion. Methods and design A multi-centre randomised controlled trial is proposed. The study will take place in five large maternity units in Ireland with collaboration between academics and clinicians in the disciplines of obstetrics and anaesthetics. It will involve 2000 women undergoing elective caesarean section after 36 weeks gestation. The main outcome measure will be major haemorrhage (blood loss >1000 ml. A study involving 2000 women will have 80% power to detect a 36% relative change in the risk of major haemorrhage with two-sided 5% alpha. Discussion It is both important and timely that we evaluate the optimal approach to the management

Study Protocol. ECSSIT – Elective Caesarean Section Syntocinon® Infusion Trial. A multi-centre randomised controlled trial of oxytocin (Syntocinon®) 5 IU bolus and placebo infusion versus oxytocin 5 IU bolus and 40 IU infusion for the control of blood loss at elective caesarean section

Science.gov (United States)

Murphy, Deirdre J; Carey, Michael; Montgomery, Alan A; Sheehan, Sharon R

2009-01-01

Background Caesarean section is one of the most commonly performed major operations in women throughout the world. Rates are escalating, with studies from the United States of America, the United Kingdom, China and the Republic of Ireland reporting rates between 20% and 25%. Operative morbidity includes haemorrhage, anaemia, blood transfusion and in severe cases, maternal death. The value of routine oxytocics in the third stage of vaginal birth has been well established and it has been assumed that these benefits apply to caesarean delivery as well. A slow bolus dose of oxytocin is recommended following delivery of the baby at caesarean section. Some clinicians use an additional infusion of oxytocin for a further period following the procedure. Intravenous oxytocin has a very short half-life (4–10 minutes) therefore the potential advantage of an oxytocin infusion is that it maintains uterine contractility throughout the surgical procedure and immediate postpartum period, when most primary haemorrhages occur. The few trials to date addressing the optimal approach to preventing haemorrhage at caesarean section have been under-powered to evaluate clinically important outcomes. There has been no trial to date comparing the use of an intravenous slow bolus of oxytocin versus an oxytocin bolus and infusion. Methods and design A multi-centre randomised controlled trial is proposed. The study will take place in five large maternity units in Ireland with collaboration between academics and clinicians in the disciplines of obstetrics and anaesthetics. It will involve 2000 women undergoing elective caesarean section after 36 weeks gestation. The main outcome measure will be major haemorrhage (blood loss >1000 ml). A study involving 2000 women will have 80% power to detect a 36% relative change in the risk of major haemorrhage with two-sided 5% alpha. Discussion It is both important and timely that we evaluate the optimal approach to the management of the third stage at

Production Support Flight Control Computers: Research Capability for F/A-18 Aircraft at Dryden Flight Research Center

Science.gov (United States)

Carter, John F.

1997-01-01

NASA Dryden Flight Research Center (DFRC) is working with the United States Navy to complete ground testing and initiate flight testing of a modified set of F/A-18 flight control computers. The Production Support Flight Control Computers (PSFCC) can give any fleet F/A-18 airplane an in-flight, pilot-selectable research control law capability. NASA DFRC can efficiently flight test the PSFCC for the following four reasons: (1) Six F/A-18 chase aircraft are available which could be used with the PSFCC; (2) An F/A-18 processor-in-the-loop simulation exists for validation testing; (3) The expertise has been developed in programming the research processor in the PSFCC; and (4) A well-defined process has been established for clearing flight control research projects for flight. This report presents a functional description of the PSFCC. Descriptions of the NASA DFRC facilities, PSFCC verification and validation process, and planned PSFCC projects are also provided.

Manufacture and test of prototype water pipe chase barrier in ITER Magnet Feeder system

Energy Technology Data Exchange (ETDEWEB)

Lu, Kun, E-mail: lukun@ipp.ac.cn [Institute of Plasma Physics, Shushan Hu Road 350, Hefei, Anhui (China); Wen, Xinjie; Liu, Chen; Song, Yuntao [Institute of Plasma Physics, Shushan Hu Road 350, Hefei, Anhui (China); Niu, Erwu [ITER China, 15B Fuxing Road, Beijing 100862 (China); Gung, Chenyu; Su, Man [ITER Organization, Route de Vinon-sur-Verdon – CS 90046, 13067 St Paul-lez-Durance Cedex (France)

2016-11-01

The Magnet Feeder system in the International Thermonuclear Experimental Reactor (ITER) deploys electrical currents and supercritical helium to the superconducting magnets and the magnet diagnostic signals to the operators. In the current design, the feeders located in the upper L3 level of the Tokamak gallery penetrate the Tokamak coolant water system vault, the biological shield and the cryostat. As a secondary confinement to contain the activated coolant water in the vault in the case of water pipe burst accident, a water barrier is welded between the penetration in the water pipe chase outer wall and the mid-plane of the vacuum jacket of the Feeder Coil Terminal Box (CTB). A thin-wall stainless steel diaphragm with an omega shape profile is welded around the CTB as the water barrier to endure 2 bar hydraulic pressure. In addition, the barrier is designed as a flexible compensator to withstand a maximum of 15 mm of axial displacement of the CTB in case of helium leak accident without failure. This paper presents the detail configuration, the manufacturing and assembly processes of the water barrier. Test results of the prototype water barrier under simulated accident conditions are also reported. Successful qualification of the design and manufacturing process of the water barrier lays a good foundation for the series production of this subsystem.

SR-71B - in Flight with F-18 Chase Aircraft - View from Air Force Tanker

Science.gov (United States)

1996-01-01

NASA 831, an SR-71B operated by the Dryden Flight Research Center, Edwards, California, cruises over the Mojave Desert with an F/A-18 Hornet flying safety chase. They were photographed on a 1996 mission from an Air Force refueling tanker The F/A-18 Hornet is used primarily as a safety chase and support aircraft at Dryden. As support aircraft, the F-18s are used for safety chase, pilot proficiency and aerial photography. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and sideslip, which are normally obtained with small tubes and vanes extending into the airstream. One of Dryden's SR-71s was used

An approach of long-view tomosynthesis in peripheral arterial angiographic examinations

Science.gov (United States)

Notohara, Daisuke; Nishino, Kazuyoshi; Shibata, Koichi

2011-03-01

Tomosynthesis (TS) has been evaluated as a useful diagnostic imaging tool for the orthopedic market and lung cancer screening. Previously, we proposed Long-View Tomosynthesis (LVTS) to apply further clinical application by expanding the reconstructed region of TS. LVTS method consists of three steps. First, it acquires multiple images while X-ray tube and Flat Panel Detector (FPD) are moving in the same linear direction simultaneously at a constant speed. Second, each image is divided into fixed length strips, and then the strips from different images having similar X-ray beam trajectory angles are stitched together. Last, multi slice coronal images are reconstructed by utilizing the Filtered Back Projection (FBP) technique from the long stitched images. The present LVTS method requires the acquisition by the constant speed motion to stitch each strip precisely. It is necessary to improve the LVTS method to apply peripheral angiographic examinations that are usually acquired at arbitrary variable speeds to chase the contrast media in the blood vessel. We propose adding the method of detecting the moved distance of frames along with anatomical structure and the method of selecting pixel values with contrast media to stitching algorithm. As a result, LVTS can extract new clinical information like 3-D structure of superficial femoral arteries and the entire blood vessel from images already acquired by routine bolus chasing techniques.

A qualitative feasibility study to inform a randomised controlled trial of fluid bolus therapy in septic shock.

Science.gov (United States)

O'Hara, Caitlin B; Canter, Ruth R; Mouncey, Paul R; Carter, Anjali; Jones, Nicola; Nadel, Simon; Peters, Mark J; Lyttle, Mark D; Harrison, David A; Rowan, Kathryn M; Inwald, David; Woolfall, Kerry

2018-01-01

The Fluids in Shock (FiSh) Trial proposes to evaluate whether restrictive fluid bolus therapy (10 mL/kg) is more beneficial than current recommended practice (20 mL/kg) in the resuscitation of children with septic shock in the UK. This qualitative feasibility study aimed to explore acceptability of the FiSh Trial, including research without prior consent (RWPC), potential barriers to recruitment and participant information for a pilot trial. Qualitative interview study involving parents of children who had presented to a UK emergency department or been admitted to a paediatric intensive care unit with severe infection in the previous 3 years. Twenty-one parents (seven bereaved) were interviewed 16 (median) months since their child's hospital admission (range: 1-41). All parents said they would have provided consent for the use of their child's data in the FiSh Trial. The majority were unfamiliar with RWPC, yet supported its use. Parents were initially concerned about the change from currently recommended treatment, yet were reassured by explanations of the current evidence base, fluid bolus therapy and monitoring procedures. Parents made recommendations about the timing of the research discussion and content of participant information. Bereaved parents stated that recruiters should not discuss research immediately after a child's death, but supported a personalised postal 'opt-out' approach to consent. Findings show that parents whose child has experienced severe infection supported the proposed FiSh Trial, including the use of RWPC. Parents' views informed the development of the pilot trial protocol and site staff training. ISRCTN15244462-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Chasing the Mirage: a grounded theory of the clinical reasoning processes that Registered Nurses use to recognize delirium.

Science.gov (United States)

El Hussein, Mohamed; Hirst, Sandra

2016-02-01

The aim of this study was to construct a grounded theory that explains the clinical reasoning processes that registered nurses use to recognize delirium in older adults in acute care hospitals. Delirium is under-recognized in acute hospital settings, this may stem from underdeveloped clinical reasoning processes. Little is known about registered nurses' (RNs) clinical reasoning processes in complex situations such as delirium recognition. A grounded theory approach was used to analyse interview data about the clinical reasoning processes of RNs in acute hospital settings. Seventeen RNs were recruited. Concurrent data collection and comparative analysis and theoretical sampling were conducted in 2013-2014. The core category to emerge from the data was 'chasing the mirage', which describes RNs' clinical reasoning processes to recognize delirium during their interaction with older adults. Understanding the reasoning that contributes to delirium under-recognition provides a strategy by which, this problem can be brought to the forefront of RNs' awareness and intervention. Delirium recognition will contribute to quality care for older adults. © 2015 John Wiley & Sons Ltd.

Costs of locomotion in polar bears: when do the costs outweigh the benefits of chasing down terrestrial prey?

Science.gov (United States)

Gormezano, Linda J; McWilliams, Scott R; Iles, David T; Rockwell, Robert F

2016-01-01

Trade-offs between locomotory costs and foraging gains are key elements in determining constraints on predator-prey interactions. One intriguing example involves polar bears pursuing snow geese on land. As climate change forces polar bears to spend more time ashore, they may need to expend more energy to obtain land-based food. Given that polar bears are inefficient at terrestrial locomotion, any extra energy expended to pursue prey could negatively impact survival. However, polar bears have been regularly observed engaging in long pursuits of geese and other land animals, and the energetic worth of such behaviour has been repeatedly questioned. We use data-driven energetic models to examine how energy expenditures vary across polar bear mass and speed. For the first time, we show that polar bears in the 125-235 kg size range can profitably pursue geese, especially at slower speeds. We caution, however, that heat build-up may be the ultimate limiting factor in terrestrial chases, especially for larger bears, and this limit would be reached more quickly with warmer environmental temperatures.

Coevolutionary arms race versus host defense chase in a tropical herbivore-plant system.

Science.gov (United States)

Endara, María-José; Coley, Phyllis D; Ghabash, Gabrielle; Nicholls, James A; Dexter, Kyle G; Donoso, David A; Stone, Graham N; Pennington, R Toby; Kursar, Thomas A

2017-09-05

Coevolutionary models suggest that herbivores drive diversification and community composition in plants. For herbivores, many questions remain regarding how plant defenses shape host choice and community structure. We addressed these questions using the tree genus Inga and its lepidopteran herbivores in the Amazon. We constructed phylogenies for both plants and insects and quantified host associations and plant defenses. We found that similarity in herbivore assemblages between Inga species was correlated with similarity in defenses. There was no correlation with phylogeny, a result consistent with our observations that the expression of defenses in Inga is independent of phylogeny. Furthermore, host defensive traits explained 40% of herbivore community similarity. Analyses at finer taxonomic scales showed that different lepidopteran clades select hosts based on different defenses, suggesting taxon-specific histories of herbivore-host plant interactions. Finally, we compared the phylogeny and defenses of Inga to phylogenies for the major lepidopteran clades. We found that closely related herbivores fed on Inga with similar defenses rather than on closely related plants. Together, these results suggest that plant defenses might be more evolutionarily labile than the herbivore traits related to host association. Hence, there is an apparent asymmetry in the evolutionary interactions between Inga and its herbivores. Although plants may evolve under selection by herbivores, we hypothesize that herbivores may not show coevolutionary adaptations, but instead "chase" hosts based on the herbivore's own traits at the time that they encounter a new host, a pattern more consistent with resource tracking than with the arms race model of coevolution.

Activity and toxicity of oxaliplatin and bolus fluorouracil plus leucovorin in pretreated colorectal cancer patients: a phase 2. study

Energy Technology Data Exchange (ETDEWEB)

Ferraresi, V.; Buccilli, A.; Giannarelli, D.; Ciccarese, M. [Regina Elena Cancer Institute, Rome (Italy). Dept. of Medical Oncology; Giampaolo, M.A.; Gabriele, A.; Buccilli, A.; Gamucci, T. [Azienda Sanitaria Locale, Frosinone (Italy). Complex Operative Unit of Medical Oncology

2005-06-15

The aim of the current study was to evaluate the activity and toxicity of a combination of oxaliplatin with bolus fluorouracil and leucovorin in colorectal cancer (CRC) patients pretreated for advanced disease with various schedules including continuous fluorouracil infusion. Thirty consecutive patients with pretreated advanced CRC received oxaliplatin 130 mg/m{sup 2} by 2-h infusion dl, leucovorin 100 mg/m{sup 2} by 1-h infusion followed by fluorouracil 425 mg/m{sup 2} i.v. bolus from day 1 to 3 every 3 weeks for a maximum of 6 cycles. The best overall response rate in an intent-to-treat analysis was 13% (2 complete responses and 2 partial responses) (95% CI, 1.2-25.5%) and 37% of patients obtained stable disease with a tumor growth control rate of 50% (95% CI, 32.1-67.9%). The median progression-free survival was 4.0 months (95% CI, 1.4-6.5 months) and median overall survival was 12.0 months (95% CI, 9.9-14.1 months). The independent prognostic factors for improved overall survival were a good performance status and a response/stabilization of disease to chemotherapy. Severe neutropenia was quite common (43.3% of patients and 14.4% of cycles), although complicated by fever only in one case (3.3% of patients). There was one toxic death. In conclusion, the study combination showed an interesting rate of tumor growth control in a cohort of patients previously treated for advanced disease with various schedules including continuous fluorouracil infusion.

A Phase 1, Single-center, Double-blind, Placebo-controlled Study in Healthy Subjects to Assess the Safety, Tolerability, Clinical Effects, and Pharmacokinetics-Pharmacodynamics of Intravenous Cyclopropyl-methoxycarbonylmetomidate (ABP-700) after a Single Ascending Bolus Dose.

Science.gov (United States)

Struys, Michel M R F; Valk, Beatrijs I; Eleveld, Douglas J; Absalom, Anthony R; Meyer, Peter; Meier, Sascha; den Daas, Izaak; Chou, Thomas; van Amsterdam, Kai; Campagna, Jason A; Sweeney, Steven P

2017-07-01

Cyclopropyl-methoxycarbonylmetomidate (ABP-700) is a new "soft" etomidate analog. The primary objectives of this first-in-human study were to describe the safety and efficacy of ABP-700 and to determine its maximum tolerated dose. Secondary objectives were to characterize the pharmacokinetics of ABP-700 and its primary metabolite (cyclopropyl-methoxycarbonyl acid), to assess the clinical effects of ABP-700, and to investigate the dose-response and pharmacokinetic/pharmacodynamic relationships. Sixty subjects were divided into 10 cohorts and received an increasing, single bolus of either ABP-700 or placebo. Safety was assessed by clinical laboratory evaluations, infusion-site reactions, continuous monitoring of vital signs, physical examination, adverse event monitoring, and adrenocorticotropic hormone stimulation testing. Clinical effects were assessed with modified observer's assessment of alertness/sedation and Bispectral Index monitoring. Pharmacokinetic parameters were calculated. Stopping criteria were met at 1.00 mg/kg dose. No serious adverse events were reported. Adverse events were dose-dependent and comprised involuntary muscle movement, tachycardia, and ventilatory effects. Adrenocorticotropic hormone stimulation evoked a physiologic cortisol response in all subjects, no different from placebo. Pharmacokinetics were dose-proportional. A three-compartment pharmacokinetic model described the data well. A rapid onset of anesthesia/sedation after bolus administration and also a rapid recovery were observed. A quantitative concentration-effect relationship was described for the modified observer's assessment of alertness/sedation and Bispectral Index. This first-in-human study of ABP-700 shows that ABP-700 was safe and well tolerated after single-bolus injections up to 1.00 mg/kg. Bolus doses of 0.25 and 0.35 mg/kg were found to provide the most beneficial clinical effect versus side-effect profile.

Comparison of Two Methods of Bolus and Infusion of Tranexamic Acid in Reduction of Blood Loss in Total Knee Arthroplasty

OpenAIRE

Mohammadreza Moshari; Bahman Malek; Mohammadreza Minator-Sajjadi; Maryam Vosoghian; Mastaneh Dahi; Mahshid Ghasemi; Razieh Shekari

2018-01-01

AbstractBackground: So far, many studies have been performed to determine the optimal dose and regimen of tranexamic acid to reduce preoperative and postoperative blood loss in primary total knee arthroplasty. In the present study, two different methods of administration (bolus and infusion), were compared.Materials and Methods: Forty patients were randomized in the two groups (A and B) of 20 patients each. All patients received 500 mg tranexamic acid before inflation of tourniquet. Group A (...

Serial computed tomography and its uses in the diagnosis of pathological changes in the liver, pancreas and kidneys

International Nuclear Information System (INIS)

Schmiedel, R.

1983-01-01

The investigations described were carried out in such a way as to fulfil the defined requirements of serial computed tomography like short periods of measurement, high scanning frequency and intravasal bolus injection of a contrast medium that would readily be excreted by the renal route. In this connection, the following questions were of particular interest: 1. Is computed serial tomography able to provide better clues to tissue identification and the distinction between normal and pathological structures in the liver, pancreas and kidneys? 2. Would it be possible to obtain information as to the degree of vascularisation in space-occupying pathological processes in the liver, pancreas and kidneys? 3. Is serial computed tomography a useful tool to diagnose specific pathological changes in the liver, pancreas and kidneys? 4. Would this investigation permit predictions to be made about the functional performance of the liver, pancreas and kidneys? (orig./MG) [de

The in vitro sub-cellular localization and in vivo efficacy of novel chitosan/GMO nanostructures containing paclitaxel.

Science.gov (United States)

Trickler, W J; Nagvekar, A A; Dash, A K

2009-08-01

To determine the in vitro sub-cellular localization and in vivo efficacy of chitosan/GMO nanostructures containing paclitaxel (PTX) compared to a conventional PTX treatment (Taxol). The sub-cellular localization of coumarin-6 labeled chitosan/GMO nanostructures was determined by confocal microscopy in MDA-MB-231 cells. The antitumor efficacy was evaluated in two separate studies using FOX-Chase (CB17) SCID Female-Mice MDA-MB-231 xenograph model. Treatments consisted of intravenous Taxol or chitosan/GMO nanostructures with or without PTX, local intra-tumor bolus of Taxol or chitosan/GMO nanostructures with or without PTX. The tumor diameter and animal weight was monitored at various intervals. Histopathological changes were evaluated in end-point tumors. The tumor diameter increased at a constant rate for all the groups between days 7-14. After a single intratumoral bolus dose of chitosan/GMO containing PTX showed significant reduction in tumor diameter on day 15 when compared to control, placebo and intravenous PTX administration. The tumor diameter reached a maximal decrease (4-fold) by day 18, and the difference was reduced to approximately 2-fold by day 21. Qualitatively similar results were observed in a separate study containing PTX when administered intravenously. Chitosan/GMO nanostructures containing PTX are safe and effective administered locally or intravenously. Partially supported by DOD Award BC045664.

SU-E-T-541: Bolus Effect of Thermoplastic Masks in IMRT and VMAT Head and Neck Treatments

International Nuclear Information System (INIS)

Zhen, H; Nedzi, L; Chen, S; Jiang, S; Zhao, B

2014-01-01

Purpose: To quantitatively evaluate the bolus effect of thermoplalstic mask on patient skin dose during multi-field IMRT and VMAT treatment. Methods: The clinically approved target contours for five head and neck patients were deformably registered to an anthropomorphic Rando phantom. Two plans: Multifield IMRT plan with 7-9 beams and VMAT plan with 2-4 arcs were created for each patient following same dose constraints. 3mm skin was excluded from PTVs but not constrained during optimization. The prescription dose was 200-220 cGy/fraction. A thermoplastic head and shoulder mask was customized for the Rando phantom. Each plan was delivered to the phantom twice with and without mask. During each delivery, two rectangular strips of EBT3 films (1cm x 6.8cm) were placed across the anterior upper and lower neck near PTVs to measure the surface dose. For consistency films were positioned at same locations for same patient. A total of 8 film strips were obtained for each patient. Film dose was calibrated in the range of 0-400cGy on the day of plan delivery. For dose comparison 3 regions of interests (ROIs) of 1×1 cm 2 were selected at left, right and middle part of each film, resulting in 6 point doses at each plan delivery. Results: The films without mask show relatively uniform dose distribution while those with mask clearly show mesh pattern of mask, usually indicating an increase in skin dose. On average the increase in skin dose over all ROIs with mask was 31.9%(±14.8%) with a range of 11.4%- 58.4%. There is no statistically significant difference (p=0.44) between skin dose increase in VMAT (30.8%±15.3%) and IMRT delivery (33.0%±14.9%). Conclusion: Thermoplastic immobilization masks increase surface dose for HN patient by around 30%. The magnitude is comparable between multi-field IMRT and VMAT. Radiochromic EBT3 film serves as an effective tool to quantify bolus effect

Estimation of intrathoracic arterial diameter by means of computed tomographic angiography in Hispaniolan Amazon parrots.

Science.gov (United States)

Beaufrère, Hugues; Rodriguez, Daniel; Pariaut, Romain; Gaschen Dvm, Lorrie; Schnellbacher, Rodney; Nevarez, Javier G; Tully, Thomas N

2011-02-01

To establish a computed tomography (CT)-angiography protocol and measure the diameters of major arteries in parrots. 13 Hispaniolan Amazon parrots (Amazona ventralis). 16-slice CT scanning was used to measure the apparent diameter of the ascending aorta, abdominal aorta, pulmonary arteries, and brachiocephalic trunk. Before scanning, all birds underwent ECG and echocardiographic assessment and were considered free of detectable cardiovascular diseases. Each bird was anesthetized, and a precontrast helical CT scan was performed. Peak aortic enhancement was established with a test bolus technique via dynamic axial CT scan over a predetermined single slice. An additional bolus of contrast medium was then injected, and a helical CT-angiography scan was performed immediately afterward. Arterial diameter measurements were obtained by 2 observers via various windows before and after injection, and intra- and interobserver agreement was assessed. Reference limits were determined for arterial diameter measurements before and after contrast medium administration in pulmonary, mediastinal, and manual angiography windows. Ratios of vertebral body diameter to keel length were also calculated. Intraobserver agreement was high (concordance correlation coefficients ≥ 0.95); interobserver agreement was medium to high (intraclass correlation coefficients ≥ 0.65). CT-angiography was safe and is of potential diagnostic value in parrots. We recommend performing the angiography immediately after IV injection of 3 mL of iohexol/kg. Arterial diameter measurements at the described locations were reliable.

Technique of application of contrast media in computed tomography of the heart

International Nuclear Information System (INIS)

Heuser, L.; Friedmann, G.

1982-01-01

Cardiac imaging by means of CT requires administration of intravenous contrast medium which can be applied by infusion or by rapid bolus injection. Contrast infusion is easier in performance and yields opacification of all cardiac cavities. Using bolus technique selective enhancement of cardiac chambers can be obtained which provides increased image quality and better resolution of cardiac structures. Both techniques are described and the results of 221 examinations are analysed with special respect to image quality, technical amount and contrast media side effects. (orig.) [de

A novel pulse-chase SILAC strategy measures changes in protein decay and synthesis rates induced by perturbation of proteostasis with an Hsp90 inhibitor.

Directory of Open Access Journals (Sweden)

Ivo Fierro-Monti

Full Text Available Standard proteomics methods allow the relative quantitation of levels of thousands of proteins in two or more samples. While such methods are invaluable for defining the variations in protein concentrations which follow the perturbation of a biological system, they do not offer information on the mechanisms underlying such changes. Expanding on previous work [1], we developed a pulse-chase (pc variant of SILAC (stable isotope labeling by amino acids in cell culture. pcSILAC can quantitate in one experiment and for two conditions the relative levels of proteins newly synthesized in a given time as well as the relative levels of remaining preexisting proteins. We validated the method studying the drug-mediated inhibition of the Hsp90 molecular chaperone, which is known to lead to increased synthesis of stress response proteins as well as the increased decay of Hsp90 "clients". We showed that pcSILAC can give information on changes in global cellular proteostasis induced by treatment with the inhibitor, which are normally not captured by standard relative quantitation techniques. Furthermore, we have developed a mathematical model and computational framework that uses pcSILAC data to determine degradation constants kd and synthesis rates Vs for proteins in both control and drug-treated cells. The results show that Hsp90 inhibition induced a generalized slowdown of protein synthesis and an increase in protein decay. Treatment with the inhibitor also resulted in widespread protein-specific changes in relative synthesis rates, together with variations in protein decay rates. The latter were more restricted to individual proteins or protein families than the variations in synthesis. Our results establish pcSILAC as a viable workflow for the mechanistic dissection of changes in the proteome which follow perturbations. Data are available via ProteomeXchange with identifier PXD000538.

A Novel Pulse-Chase SILAC Strategy Measures Changes in Protein Decay and Synthesis Rates Induced by Perturbation of Proteostasis with an Hsp90 Inhibitor

Science.gov (United States)

Fierro-Monti, Ivo; Racle, Julien; Hernandez, Celine; Waridel, Patrice; Hatzimanikatis, Vassily; Quadroni, Manfredo

2013-01-01

Standard proteomics methods allow the relative quantitation of levels of thousands of proteins in two or more samples. While such methods are invaluable for defining the variations in protein concentrations which follow the perturbation of a biological system, they do not offer information on the mechanisms underlying such changes. Expanding on previous work [1], we developed a pulse-chase (pc) variant of SILAC (stable isotope labeling by amino acids in cell culture). pcSILAC can quantitate in one experiment and for two conditions the relative levels of proteins newly synthesized in a given time as well as the relative levels of remaining preexisting proteins. We validated the method studying the drug-mediated inhibition of the Hsp90 molecular chaperone, which is known to lead to increased synthesis of stress response proteins as well as the increased decay of Hsp90 “clients”. We showed that pcSILAC can give information on changes in global cellular proteostasis induced by treatment with the inhibitor, which are normally not captured by standard relative quantitation techniques. Furthermore, we have developed a mathematical model and computational framework that uses pcSILAC data to determine degradation constants kd and synthesis rates Vs for proteins in both control and drug-treated cells. The results show that Hsp90 inhibition induced a generalized slowdown of protein synthesis and an increase in protein decay. Treatment with the inhibitor also resulted in widespread protein-specific changes in relative synthesis rates, together with variations in protein decay rates. The latter were more restricted to individual proteins or protein families than the variations in synthesis. Our results establish pcSILAC as a viable workflow for the mechanistic dissection of changes in the proteome which follow perturbations. Data are available via ProteomeXchange with identifier PXD000538. PMID:24312217

Development and Clinical Implementation of a Universal Bolus to Maintain Spot Size During Delivery of Base of Skull Pencil Beam Scanning Proton Therapy

Energy Technology Data Exchange (ETDEWEB)

Both, Stefan, E-mail: Stefan.Both@uphs.upenn.edu [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Shen, Jiajian [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Department of Radiation Oncology, Mayo Clinic, Phoenix, Arizona (United States); Kirk, Maura; Lin, Liyong; Tang, Shikui; Alonso-Basanta, Michelle; Lustig, Robert; Lin, Haibo; Deville, Curtiland; Hill-Kayser, Christine; Tochner, Zelig; McDonough, James [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States)

2014-09-01

Purpose: To report on a universal bolus (UB) designed to replace the range shifter (RS); the UB allows the treatment of shallow tumors while keeping the pencil beam scanning (PBS) spot size small. Methods and Materials: Ten patients with brain cancers treated from 2010 to 2011 were planned using the PBS technique with bolus and the RS. In-air spot sizes of the pencil beam were measured and compared for 4 conditions (open field, with RS, and with UB at 2- and 8-cm air gap) in isocentric geometry. The UB was applied in our clinic to treat brain tumors, and the plans with UB were compared with the plans with RS. Results: A UB of 5.5 cm water equivalent thickness was found to meet the needs of the majority of patients. By using the UB, the PBS spot sizes are similar with the open beam (P>.1). The heterogeneity index was found to be approximately 10% lower for the UB plans than for the RS plans. The coverage for plans with UB is more conformal than for plans with RS; the largest increase in sparing is usually for peripheral organs at risk. Conclusions: The integrity of the physical properties of the PBS beam can be maintained using a UB that allows for highly conformal PBS treatment design, even in a simple geometry of the fixed beam line when noncoplanar beams are used.

Effects of orally applied butyrate bolus on histone acetylation and cytochrome P450 enzyme activity in the liver of chicken – a randomized controlled trial

Directory of Open Access Journals (Sweden)

Mátis Gábor

2013-01-01

Full Text Available Abstract Background Butyrate is known as histone deacetylase inhibitor, inducing histone hyperacetylation in vitro and playing a predominant role in the epigenetic regulation of gene expression and cell function. We hypothesized that butyrate, endogenously produced by intestinal microbial fermentation or applied as a nutritional supplement, might cause similar in vivo modifications in the chromatin structure of the hepatocytes, influencing the expression of certain genes and therefore modifying the activity of hepatic microsomal drug-metabolizing cytochrome P450 (CYP enzymes. Methods An animal study was carried out in chicken as a model to investigate the molecular mechanisms of butyrate’s epigenetic actions in the liver. Broiler chicks in the early post-hatch period were treated once daily with orally administered bolus of butyrate following overnight starvation with two different doses (0.25 or 1.25 g/kg body weight per day for five days. After slaughtering, cell nucleus and microsomal fractions were separated by differential centrifugation from the livers. Histones were isolated from cell nuclei and acetylation of hepatic core histones was screened by western blotting. The activity of CYP2H and CYP3A37, enzymes involved in biotransformation in chicken, was detected by aminopyrine N-demethylation and aniline-hydroxylation assays from the microsomal suspensions. Results Orally added butyrate, applied in bolus, had a remarkable impact on nucleosome structure of hepatocytes: independently of the dose, butyrate caused hyperacetylation of histone H2A, but no changes were monitored in the acetylation state of H2B. Intensive hyperacetylation of H3 was induced by the higher administered dose, while the lower dose tended to increase acetylation ratio of H4. In spite of the observed modification in histone acetylation, no significant changes were observed in the hepatic microsomal CYP2H and CYP3A37 activity. Conclusion Orally added butyrate in bolus

Reproducibility of 5-HT2A receptor measurements and sample size estimations with [18F]altanserin PET using a bolus/infusion approach

International Nuclear Information System (INIS)

Haugboel, Steven; Pinborg, Lars H.; Arfan, Haroon M.; Froekjaer, Vibe M.; Svarer, Claus; Knudsen, Gitte M.; Madsen, Jacob; Dyrby, Tim B.

2007-01-01

To determine the reproducibility of measurements of brain 5-HT 2A receptors with an [ 18 F]altanserin PET bolus/infusion approach. Further, to estimate the sample size needed to detect regional differences between two groups and, finally, to evaluate how partial volume correction affects reproducibility and the required sample size. For assessment of the variability, six subjects were investigated with [ 18 F]altanserin PET twice, at an interval of less than 2 weeks. The sample size required to detect a 20% difference was estimated from [ 18 F]altanserin PET studies in 84 healthy subjects. Regions of interest were automatically delineated on co-registered MR and PET images. In cortical brain regions with a high density of 5-HT 2A receptors, the outcome parameter (binding potential, BP 1 ) showed high reproducibility, with a median difference between the two group measurements of 6% (range 5-12%), whereas in regions with a low receptor density, BP 1 reproducibility was lower, with a median difference of 17% (range 11-39%). Partial volume correction reduced the variability in the sample considerably. The sample size required to detect a 20% difference in brain regions with high receptor density is approximately 27, whereas for low receptor binding regions the required sample size is substantially higher. This study demonstrates that [ 18 F]altanserin PET with a bolus/infusion design has very low variability, particularly in larger brain regions with high 5-HT 2A receptor density. Moreover, partial volume correction considerably reduces the sample size required to detect regional changes between groups. (orig.)

Metastasizing, Luciferase Transduced MAT-Lu Rat Prostate Cancer Models: Follow up of Bolus and Metronomic Therapy with Doxorubicin as Model Drug

International Nuclear Information System (INIS)

Jantscheff, Peter; Esser, Norbert; Geipel, Andreas; Woias, Peter; Ziroli, Vittorio; Goldschmidtboing, Frank; Massing, Ulrich

2011-01-01

The most fatal outcomes of prostate carcinoma (PCa) result from hormone-refractory variants of the tumor, especially from metastatic spread rather than from primary tumor burden. The goal of the study was to establish and apply rat MAT-Lu prostate cancer tumor models for improved non-invasive live follow up of tumor growth and metastasis by in vivo bioluminescence. We established luciferase transduced MAT-Lu rat PCa cells and studied tumor growth and metastatic processes in an ectopic as well as orthotopic setting. An intravenous bolus treatment with doxorubicin was used to demonstrate the basic applicability of in vivo imaging to follow up therapeutic intervention in these models. In vitro analysis of tissue homogenates confirmed major metastatic spread of subcutaneous tumors into the lung. Our sensitive method, however, for the first time detects metastasis also in lymph node (11/24), spleen (3/24), kidney (4/24), liver (5/24), and bone tissue (femur or spinal cord - 5/20 and 12/20, respectively). Preliminary data of orthotopic implantation (three animals) showed metastatic invasion to investigated organs in all animals but with varying preference (e.g., to lymph nodes). Intravenous bolus treatment of MAT-Lu PCa with doxorubicin reduced subcutaneous tumor growth by about 50% and the number of animals affected by metastatic lesions in lymph nodes (0/4), lung (3/6) or lumbar spine (0/2), as determined by in vivo imaging and in vitro analysis. Additionally, the possible applicability of the luciferase transduced MAT-Lu model(s) to study basic principles of metronomic therapies via jugular vein catheter, using newly established active microport pumping systems, is presented

Metastasizing, Luciferase Transduced MAT-Lu Rat Prostate Cancer Models: Follow up of Bolus and Metronomic Therapy with Doxorubicin as Model Drug

Energy Technology Data Exchange (ETDEWEB)

Jantscheff, Peter, E-mail: jantscheff@tumorbio.uni-freiburg.de [Tumour Biology Center, Clinical Research, Department Lipids & Liposomes, Breisacher Str.117, D-79106 Freiburg (Germany); Esser, Norbert [ProQinase GmbH, Breisacher Str. 117, D-79106 Freiburg (Germany); Geipel, Andreas; Woias, Peter [Laboratory for Design of Microsystems, Department of Microsystems Engineering (IMTEK), Georges-Köhler-Allee 106, D-79110 Freiburg (Germany); Ziroli, Vittorio [Tumour Biology Center, Clinical Research, Department Lipids & Liposomes, Breisacher Str.117, D-79106 Freiburg (Germany); Goldschmidtboing, Frank [Laboratory for Design of Microsystems, Department of Microsystems Engineering (IMTEK), Georges-Köhler-Allee 106, D-79110 Freiburg (Germany); Massing, Ulrich [Tumour Biology Center, Clinical Research, Department Lipids & Liposomes, Breisacher Str.117, D-79106 Freiburg (Germany)

2011-06-17

The most fatal outcomes of prostate carcinoma (PCa) result from hormone-refractory variants of the tumor, especially from metastatic spread rather than from primary tumor burden. The goal of the study was to establish and apply rat MAT-Lu prostate cancer tumor models for improved non-invasive live follow up of tumor growth and metastasis by in vivo bioluminescence. We established luciferase transduced MAT-Lu rat PCa cells and studied tumor growth and metastatic processes in an ectopic as well as orthotopic setting. An intravenous bolus treatment with doxorubicin was used to demonstrate the basic applicability of in vivo imaging to follow up therapeutic intervention in these models. In vitro analysis of tissue homogenates confirmed major metastatic spread of subcutaneous tumors into the lung. Our sensitive method, however, for the first time detects metastasis also in lymph node (11/24), spleen (3/24), kidney (4/24), liver (5/24), and bone tissue (femur or spinal cord - 5/20 and 12/20, respectively). Preliminary data of orthotopic implantation (three animals) showed metastatic invasion to investigated organs in all animals but with varying preference (e.g., to lymph nodes). Intravenous bolus treatment of MAT-Lu PCa with doxorubicin reduced subcutaneous tumor growth by about 50% and the number of animals affected by metastatic lesions in lymph nodes (0/4), lung (3/6) or lumbar spine (0/2), as determined by in vivo imaging and in vitro analysis. Additionally, the possible applicability of the luciferase transduced MAT-Lu model(s) to study basic principles of metronomic therapies via jugular vein catheter, using newly established active microport pumping systems, is presented.

Metastasizing, Luciferase Transduced MAT‑Lu Rat Prostate Cancer Models: Follow up of Bolus and Metronomic Therapy with Doxorubicin as Model Drug

Directory of Open Access Journals (Sweden)

Peter Woias

2011-06-01

Full Text Available The most fatal outcomes of prostate carcinoma (PCa result from hormone-refractory variants of the tumor, especially from metastatic spread rather than from primary tumor burden. The goal of the study was to establish and apply rat MAT-Lu prostate cancer tumor models for improved non-invasive live follow up of tumor growth and metastasis by in vivo bioluminescence. We established luciferase transduced MAT-Lu rat PCa cells and studied tumor growth and metastatic processes in an ectopic as well as orthotopic setting. An intravenous bolus treatment with doxorubicin was used to demonstrate the basic applicability of in vivo imaging to follow up therapeutic intervention in these models. In vitro analysis of tissue homogenates confirmed major metastatic spread of subcutaneous tumors into the lung. Our sensitive method, however, for the first time detects metastasis also in lymph node (11/24, spleen (3/24, kidney (4/24, liver (5/24, and bone tissue (femur or spinal cord - 5/20 and 12/20, respectively. Preliminary data of orthotopic implantation (three animals showed metastatic invasion to investigated organs in all animals but with varying preference (e.g., to lymph nodes. Intravenous bolus treatment of MAT-Lu PCa with doxorubicin reduced subcutaneous tumor growth by about 50% and the number of animals affected by metastatic lesions in lymph nodes (0/4, lung (3/6 or lumbar spine (0/2, as determined by in vivo imaging and in vitro analysis. Additionally, the possible applicability of the luciferase transduced MAT-Lu model(s to study basic principles of metronomic therapies via jugular vein catheter, using newly established active microport pumping systems, is presented.

Magnetic Resonance angiography with bolus contrast agent in abdominal aortic aneurysms

International Nuclear Information System (INIS)

Di Cesare, E.; Cerone, G.; Giordano, A.V.; Marsili, L.; Barile, A.; Michelini, O.; Masciocchi, C.; Spartera, C.

2000-01-01

Purpose of this paper is to investigate the potentials of 3D breath-hold contrast-enhanced Magnetic Resonance Angiography (MRA) in the diagnosis, follow-up and treatment planning of abdominal aortic aneurysms. Twenty-four patients with infrarenal aortic aneurysm underwent MRA. It was used a 1.5 T unit (GE Horizon, Echospeed 8.2), a phased array surface coil and 3D Fast SPGR T1-weighted sequences acquired on the coronal plane during patient breath-hold and after contrast agent i.v. administration. A bolus-test was done before angiography to optimize imaging delay time. After 3D MRA a Fast-SPGR T1-weighted sequence was acquired on the axial plane. The 3D MRA source images were processed with the MIP algorithm. Qualitative and quantitative analyses were carried out. Helical CT was performed in 6 cases and DSA in 7 cases. Surgery was the reference standard in 15 patients. MRA depicted aneurysm thrombosis in 22 cases, carrefour involvement in 18 cases and iliac arteries involvement in 3 cases. Accessory renal arteries were shown in 4 cases; iliac artery stenosis was associated in 5 cases. There was agreement between MR and Helical CT and DSA findings: surgery confirmed MRA results in 15/15 cases. 3D contrast-enhanced MRA can be considered the method of choice in the follow-up and treatment planning of abdominal aortic aneurysms, because it provides both angiographic and tomographic images: this allows to obtain more information, noninvasively and without the use of ionizing radiations [it

Insulin Degludec/Insulin Aspart Administered Once Daily at Any Meal, With Insulin Aspart at Other Meals Versus a Standard Basal-Bolus Regimen in Patients With Type 1 Diabetes

Science.gov (United States)

Hirsch, Irl B.; Bode, Bruce; Courreges, Jean-Pierre; Dykiel, Patrik; Franek, Edward; Hermansen, Kjeld; King, Allen; Mersebach, Henriette; Davies, Melanie

2012-01-01

OBJECTIVE To evaluate efficacy and tolerability of a co-formulation of insulin degludec and insulin aspart (IDegAsp) with insulin aspart (IAsp) at other meals compared with basal-bolus therapy using insulin detemir (IDet) and IAsp. RESEARCH DESIGN AND METHODS Adults (n = 548) with type 1 diabetes (A1C 7.0–10.0%; BMI ≤35.0 kg/m2) were randomized 2:1 in a 26-week, multinational, parallel-group, treat-to-target trial to IDegAsp or IDet. IDegAsp was given with a meal, and IDet was given in the evening, with a second (breakfast) dose added if needed. RESULTS Non-inferiority for IDegAsp versus IDet was confirmed; A1C improved by 0.75% with IDegAsp and 0.70% with IDet to 7.6% in both groups (estimated treatment difference IDegAsp − IDet: –0.05% [95% CI –0.18 to 0.08]). There was no statistically significant difference between IDegAsp and IDet in the rates of severe hypoglycemia (0.33 and 0.42 episodes/patient-year, respectively) or overall confirmed (plasma glucose <3.1 mmol/L) hypoglycemia (39.17 and 44.34 episodes/patient-year, respectively). Nocturnal confirmed hypoglycemia rate was 37% lower with IDegAsp than IDet (3.71 vs. 5.72 episodes/patient-year, P < 0.05). Weight gain was 2.3 and 1.3 kg with IDegAsp and IDet, respectively (P < 0.05). Total insulin dose was 13% lower in the IDegAsp group (P < 0.0001). No treatment differences were detected in Health-Related Quality of Life, laboratory measurements, physical examination, vital signs, electrocardiograms, fundoscopy, or adverse events. CONCLUSIONS IDegAsp in basal-bolus therapy with IAsp at additional mealtimes improves overall glycemic control and was non-inferior to IDet, with a reduced risk of nocturnal hypoglycemia and fewer injections in comparison with IDet + IAsp basal-bolus therapy. PMID:22933438

Model of the Glucose-Insulin-Glucagon Dynamics after Subcutaneous Administration of a Glucagon Rescue Bolus in Healthy Humans

DEFF Research Database (Denmark)

Wendt, Sabrina Lyngbye; Møller, Jan Kloppenborg; Haidar, Ahmad

In healthy individuals, insulin and glucagon work in a complex fashion to maintain blood glucose levels within a narrow range. This regulation is distorted in patients with diabetes. The hepatic glucose response due to an elevated glucagon level depends on the current insulin concentration and thus...... endogenous glucose production (EGP) can not be modelled without knowledge of the concentration of both hormones in plasma. Furthermore, literature suggests an upper limit to EGP irrespective of glucagon levels. We build a simulation model of the glucose-insulin-glucagon dynamics in man including saturation...... effect of EGP. Ten healthy subjects received a 1 mg subcutaneous (SC) glucagon bolus (GlucaGen®). Plasma samples were collected until 300 minutes post dose and analyzed for glucagon, insulin, and glucose concentrations. All observations were used to fit a physiological model of the glucose...

Peak-counts blood flow model-errors and limitations

International Nuclear Information System (INIS)

Mullani, N.A.; Marani, S.K.; Ekas, R.D.; Gould, K.L.

1984-01-01

The peak-counts model has several advantages, but its use may be limited due to the condition that the venous egress may not be negligible at the time of peak-counts. Consequently, blood flow measurements by the peak-counts model will depend on the bolus size, bolus duration, and the minimum transit time of the bolus through the region of interest. The effect of bolus size on the measurement of extraction fraction and blood flow was evaluated by injecting 1 to 30ml of rubidium chloride in the femoral vein of a dog and measuring the myocardial activity with a beta probe over the heart. Regional blood flow measurements were not found to vary with bolus sizes up to 30ml. The effect of bolus duration was studied by injecting a 10cc bolus of tracer at different speeds in the femoral vein of a dog. All intravenous injections undergo a broadening of the bolus duration due to the transit time of the tracer through the lungs and the heart. This transit time was found to range from 4-6 second FWHM and dominates the duration of the bolus to the myocardium for up to 3 second injections. A computer simulation has been carried out in which the different parameters of delay time, extraction fraction, and bolus duration can be changed to assess the errors in the peak-counts model. The results of the simulations show that the error will be greatest for short transit time delays and for low extraction fractions

An isotope approach based on C-13 pulse-chase labelling vs. the root trenching method to separate heterotrophic and autotrophic respiration in cultivated peatlands

Energy Technology Data Exchange (ETDEWEB)

Biasi, C.; Pitkamaki, A. S.; Tavi, N. M.; Koponen, H. T.; Martikainen, P. J. [Univ.of Eastern Finland, Kuopio (Finland). Dept. of Environmental Science], e-mail: christina.biasi@uef.fi

2012-11-01

We tested an isotope method based on C-13 pulse-chase labelling for determining the fractional contribution of soil microbial respiration to overall soil respiration in an organic soil (cutaway peatland, eastern Finland), cultivated with the bioenergy crop, reed canary grass. The plants were exposed to CO{sub 2}-13 for five hours and the label was thereafter determined in CO{sub 2} derived from the soil-root system. A two-pool isotope mixing model was used to separate sources of respiration. The isotopic approach showed that a minimum of 50% of the total CO{sub 2} originated from soil-microbial respiration. Even though the method uses undisturbed soil-plant systems, it has limitations concerning the experimental determination of the true isotopic signal of all components contributing to autotrophic respiration. A trenching experiment which was comparatively conducted resulted in a 71% fractional contribution of soil-microbial respiration. This value was likely overestimated. Further studies are needed to evaluate critically the output from these two partitioning approaches. (orig.)

Multidetector row computed tomography may accurately estimate plaque vulnerability. Does MDCT accurately estimate plaque vulnerability? (Pro)

International Nuclear Information System (INIS)

Komatsu, Sei; Imai, Atsuko; Kodama, Kazuhisa

2011-01-01

Over the past decade, multidetector row computed tomography (MDCT) has become the most reliable and established of the noninvasive examination techniques for detecting coronary heart disease. Now MDCT is chasing intravascular ultrasound (IVUS) in terms of spatial resolution. Among the components of vulnerable plaque, MDCT may detect lipid-rich plaque, the lipid pool, and calcified spots using computed tomography number. Plaque components are detected by MDCT with high accuracy compared with IVUS and angioscopy when assessing vulnerable plaque. The TWINS study and TOGETHAR trial demonstrated that angioscopic loss of yellow color occurred independently of volumetric plaque change by statin therapy. These 2 studies showed that plaque stabilization and regression reflect independent processes mediated by different mechanisms and time course. Noncalcified plaque and/or low-density plaque was found to be the strongest predictor of cardiac events, regardless of lesion severity, and act as a potential marker of plaque vulnerability. MDCT may be an effective tool for early triage of patients with chest pain who have a normal electrocardiogram (ECG) and cardiac enzymes in the emergency department. MDCT has the potential ability to analyze coronary plaque quantitatively and qualitatively if some problems are resolved. MDCT may become an essential tool for detecting and preventing coronary artery disease in the future. (author)

Postmastectomy radiotherapy with integrated scar boost using helical tomotherapy

International Nuclear Information System (INIS)

Rong Yi; Yadav, Poonam; Welsh, James S.; Fahner, Tasha; Paliwal, Bhudatt

2012-01-01

The purpose of this study was to evaluate helical tomotherapy dosimetry in postmastectomy patients undergoing treatment for chest wall and positive nodal regions with simultaneous integrated boost (SIB) in the scar region using strip bolus. Six postmastectomy patients were scanned with a 5-mm-thick strip bolus covering the scar planning target volume (PTV) plus 2-cm margin. For all 6 cases, the chest wall received a total cumulative dose of 49.3–50.4 Gy with daily fraction size of 1.7–2.0 Gy. Total dose to the scar PTV was prescribed to 58.0–60.2 Gy at 2.0–2.5 Gy per fraction. The supraclavicular PTV and mammary nodal PTV received 1.7–1.9 dose per fraction. Two plans (with and without bolus) were generated for all 6 cases. To generate no-bolus plans, strip bolus was contoured and overrode to air density before planning. The setup reproducibility and delivered dose accuracy were evaluated for all 6 cases. Dose-volume histograms were used to evaluate dose-volume coverage of targets and critical structures. We observed reduced air cavities with the strip bolus setup compared with what we normally see with the full bolus. The thermoluminescence dosimeters (TLD) in vivo dosimetry confirmed accurate dose delivery beneath the bolus. The verification plans performed on the first day megavoltage computed tomography (MVCT) image verified that the daily setup and overall dose delivery was within 2% accuracy compared with the planned dose. The hotspot of the scar PTV in no-bolus plans was 111.4% of the prescribed dose averaged over 6 cases compared with 106.6% with strip bolus. With a strip bolus only covering the postmastectomy scar region, we observed increased dose uniformity to the scar PTV, higher setup reproducibility, and accurate dose delivered beneath the bolus. This study demonstrates the feasibility of using a strip bolus over the scar using tomotherapy for SIB dosimetry in postmastectomy treatments.

A feasibility study of a 3-day basal-bolus insulin delivery device in individuals with type 2 diabetes.

Science.gov (United States)

Mader, Julia K; Lilly, Leslie C; Aberer, Felix; Korsatko, Stefan; Strock, Ellie; Mazze, Roger S; Damsbo, Peter; Pieber, Thomas R

2014-05-01

This study tested the feasibility of transition from multiple daily injections (MDI) to a 3-day, basal-bolus insulin delivery device (PaQ) for type 2 diabetes (T2D). Twenty MDI-treated individuals with T2D with HbA(1c) ≤9% (75 mmol/mol) were enrolled in a single-center, single-arm pilot study, lasting three 2-week periods: baseline (MDI), transition to PaQ, and PaQ therapy. Feasibility of use, glycemic control, safety, and patient satisfaction were assessed. Nineteen participants transitioned to PaQ treatment and demonstrated competency in assembling, placing, and using the device. Self-monitored blood glucose and blinded continuous glucose-monitoring data showed glycemic control similar to MDI. Study participants reported high satisfaction and device acceptance. PaQ treatment is both feasible and acceptable in individuals with T2D. Transition from MDI is easy and safe. PaQ treatment might lead to better therapy adherence and improvements in glycemic control and clinical outcomes.

Capillary permeability of 99mTc-DTPA in canine myocardium determined by intracoronary bolus injection and residue detection

DEFF Research Database (Denmark)

Svendsen, Jesper Hastrup; Efsen, F; Haunsø, S

1989-01-01

chest dogs (group A) these indicators were administered separately as bolus injections into a cannulated diagonal branch of the left anterior descending coronary artery (LAD) and the curve of the response function was recorded by external activity registration. In further experiments on closed and open...... chest dogs (group B) 99mTc-DTPA was injected via a coronary angiography catheter into the ostium of the left coronary artery and the response curve was obtained by external registration. Regional myocardial perfusion coefficients were determined by the local 133xenon washout technique and from kinetic...... by local 133Xe washout technique. Mean values of the extraction fractions (E) were 0.463 and 0.475 for 99mTc-DTPA and 51Cr-EDTA, and the permeability-surface area products (PdS) were 52.8 and 57.5 ml.min-1.100 g-1 respectively. At the conventional capillary surface area estimate of 500 cm2.g-1...

Tube potential can be lowered to 80 kVp in test bolus phase of CT coronary angiography (CTCA) and CT pulmonary angiography (CTPA) to save dose without compromising diagnostic quality

International Nuclear Information System (INIS)

Rodrigues, J.C.L.; Manghat, N.E.; Hamilton, M.C.K.; Joshi, D.; Lyen, S.M.; Negus, I.S.

2014-01-01

The purpose of this study was to determine whether performing the test bolus (TB) of computed tomography coronary angiography (CTCA) and computed tomography pulmonary angiography (CTPA) at 80 kVp reduces dose without compromising diagnostic quality. An 80 kVp TB protocol for CTCA and CTPA was retrospectively compared to standard TB protocol (non-obese: 100 kVp, obese: 120 kVp). CT angiogram parameters were unchanged between cohorts. Thirty-seven consecutive 80 kVp TB CTCA images were compared to 53 standard CTCA images. Fifty consecutive CTPAs from each protocol were analysed. Diagnostic quality of the CT angiogram was assessed by: mean attenuation, signal-to-noise ratio (SNR) in the ascending aorta (AA) in CTCA and in the main pulmonary artery (MPA) in CTPA, diagnostic rate, and number of repeated monitoring scans. Mean effective dose was estimated using the dose-length product. Mean TB effective doses were significantly lower (P < 0.0001) for 80 kVp scans compared to the standard in non-obese CTCA (0.15 ± 0.04 mSv Vs 0.33 ± 0.09 mSv), obese CTCA (0.17 ± 0.06 mSv Vs 0.57 ± 0.12 mSv), and CTPA patients (0.07 ± 0.03 mSv Vs 0.15 ± 0.06 mSv). No difference was demonstrated in mean attenuation, SNR (AA), SNR (MPA), diagnostic rates, or number of repeated monitoring scans between protocols. Routinely performing TB at 80 kVp, regardless of body habitus, in CTCA and CTPA results in a small but significant dose reduction, without compromising CT angiogram diagnostic quality. (orig.)

Tube potential can be lowered to 80 kVp in test bolus phase of CT coronary angiography (CTCA) and CT pulmonary angiography (CTPA) to save dose without compromising diagnostic quality

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, J.C.L.; Manghat, N.E.; Hamilton, M.C.K. [University Hospitals Bristol NHS Foundation Trust, Department of Radiology, Bristol Royal Infirmary, Bristol (United Kingdom); University Hospitals Bristol NHS Foundation Trust, National Institute for Health Research (NIHR) Cardiovascular Biomedical Research Unit, Bristol Heart Institute, Bristol Royal Infirmary, Bristol (United Kingdom); Joshi, D.; Lyen, S.M. [University Hospitals Bristol NHS Foundation Trust, Department of Radiology, Bristol Royal Infirmary, Bristol (United Kingdom); Negus, I.S. [University Hospitals Bristol NHS Foundation Trust, Department of Medical Physics and Bioengineering, Bristol Royal Infirmary, Bristol (United Kingdom)

2014-10-15

The purpose of this study was to determine whether performing the test bolus (TB) of computed tomography coronary angiography (CTCA) and computed tomography pulmonary angiography (CTPA) at 80 kVp reduces dose without compromising diagnostic quality. An 80 kVp TB protocol for CTCA and CTPA was retrospectively compared to standard TB protocol (non-obese: 100 kVp, obese: 120 kVp). CT angiogram parameters were unchanged between cohorts. Thirty-seven consecutive 80 kVp TB CTCA images were compared to 53 standard CTCA images. Fifty consecutive CTPAs from each protocol were analysed. Diagnostic quality of the CT angiogram was assessed by: mean attenuation, signal-to-noise ratio (SNR) in the ascending aorta (AA) in CTCA and in the main pulmonary artery (MPA) in CTPA, diagnostic rate, and number of repeated monitoring scans. Mean effective dose was estimated using the dose-length product. Mean TB effective doses were significantly lower (P < 0.0001) for 80 kVp scans compared to the standard in non-obese CTCA (0.15 ± 0.04 mSv Vs 0.33 ± 0.09 mSv), obese CTCA (0.17 ± 0.06 mSv Vs 0.57 ± 0.12 mSv), and CTPA patients (0.07 ± 0.03 mSv Vs 0.15 ± 0.06 mSv). No difference was demonstrated in mean attenuation, SNR (AA), SNR (MPA), diagnostic rates, or number of repeated monitoring scans between protocols. Routinely performing TB at 80 kVp, regardless of body habitus, in CTCA and CTPA results in a small but significant dose reduction, without compromising CT angiogram diagnostic quality. (orig.)

A comparative study of computed tomography with surgical specimen in 32 cases of hyperparathyroidism

International Nuclear Information System (INIS)

Iwamoto, Noriyuki; Yamazaki, Satoru; Hukuda, Toyofumi

1984-01-01

We have been localizing pathological parathyroid glands by computed tomography(CT) since December '80. We reviewed 32 cases of surgically-treated hyperparathyroidism, in which 99 parathyroid glands were resected, each weight ranging from 20 to 3300 mg. Comparing the resected parathyroid glands with preoperative CT, we concluded as follows: 1) Pathological parathyroid glands were identified in 25 of the 32 cases (78 %). 2) In parathyroid glands weighing over 300mg, 60 from 64 glands (94 %) were identified by CT. 3) In secondary hyperaparathyroidism with radiologically proven subperiosteal resorption, pathologically-enlarged parathyroid glands were identified by CT in 22 from 23 cases (95%). CT was considered a useful diagnostic method in secondary hyperparathyroidism. 4) Experiencing 2 false-positive cases and one false-negative, which were ectopic cases, we concluded it necesary to use bolus-enhancement in localizing ectopic parathyroid glands. (author)

Biased visualization of hypoperfused tissue by computed tomography due to short imaging duration: improved classification by image down-sampling and vascular models

Energy Technology Data Exchange (ETDEWEB)

Mikkelsen, Irene Klaerke; Ribe, Lars Riisgaard; Bekke, Susanne Lise; Tietze, Anna; Oestergaard, Leif; Mouridsen, Kim [Aarhus University Hospital, Center of Functionally Integrative Neuroscience, Aarhus C (Denmark); Jones, P.S.; Alawneh, Josef [University of Cambridge, Department of Clinical Neurosciences, Cambridge (United Kingdom); Puig, Josep; Pedraza, Salva [Dr. Josep Trueta Girona University Hospitals, Department of Radiology, Girona Biomedical Research Institute, Girona (Spain); Gillard, Jonathan H. [University of Cambridge, Department of Radiology, Cambridge (United Kingdom); Warburton, Elisabeth A. [Cambrigde University Hospitals, Addenbrooke, Stroke Unit, Cambridge (United Kingdom); Baron, Jean-Claude [University of Cambridge, Department of Clinical Neurosciences, Cambridge (United Kingdom); Centre Hospitalier Sainte Anne, INSERM U894, Paris (France)

2015-07-15

Lesion detection in acute stroke by computed-tomography perfusion (CTP) can be affected by incomplete bolus coverage in veins and hypoperfused tissue, so-called bolus truncation (BT), and low contrast-to-noise ratio (CNR). We examined the BT-frequency and hypothesized that image down-sampling and a vascular model (VM) for perfusion calculation would improve normo- and hypoperfused tissue classification. CTP datasets from 40 acute stroke patients were retrospectively analysed for BT. In 16 patients with hypoperfused tissue but no BT, repeated 2-by-2 image down-sampling and uniform filtering was performed, comparing CNR to perfusion-MRI levels and tissue classification to that of unprocessed data. By simulating reduced scan duration, the minimum scan-duration at which estimated lesion volumes came within 10 % of their true volume was compared for VM and state-of-the-art algorithms. BT in veins and hypoperfused tissue was observed in 9/40 (22.5 %) and 17/40 patients (42.5 %), respectively. Down-sampling to 128 x 128 resolution yielded CNR comparable to MR data and improved tissue classification (p = 0.0069). VM reduced minimum scan duration, providing reliable maps of cerebral blood flow and mean transit time: 5 s (p = 0.03) and 7 s (p < 0.0001), respectively. BT is not uncommon in stroke CTP with 40-s scan duration. Applying image down-sampling and VM improve tissue classification. (orig.)

Biased visualization of hypoperfused tissue by computed tomography due to short imaging duration: improved classification by image down-sampling and vascular models

International Nuclear Information System (INIS)

Mikkelsen, Irene Klaerke; Ribe, Lars Riisgaard; Bekke, Susanne Lise; Tietze, Anna; Oestergaard, Leif; Mouridsen, Kim; Jones, P.S.; Alawneh, Josef; Puig, Josep; Pedraza, Salva; Gillard, Jonathan H.; Warburton, Elisabeth A.; Baron, Jean-Claude

2015-01-01

Lesion detection in acute stroke by computed-tomography perfusion (CTP) can be affected by incomplete bolus coverage in veins and hypoperfused tissue, so-called bolus truncation (BT), and low contrast-to-noise ratio (CNR). We examined the BT-frequency and hypothesized that image down-sampling and a vascular model (VM) for perfusion calculation would improve normo- and hypoperfused tissue classification. CTP datasets from 40 acute stroke patients were retrospectively analysed for BT. In 16 patients with hypoperfused tissue but no BT, repeated 2-by-2 image down-sampling and uniform filtering was performed, comparing CNR to perfusion-MRI levels and tissue classification to that of unprocessed data. By simulating reduced scan duration, the minimum scan-duration at which estimated lesion volumes came within 10 % of their true volume was compared for VM and state-of-the-art algorithms. BT in veins and hypoperfused tissue was observed in 9/40 (22.5 %) and 17/40 patients (42.5 %), respectively. Down-sampling to 128 x 128 resolution yielded CNR comparable to MR data and improved tissue classification (p = 0.0069). VM reduced minimum scan duration, providing reliable maps of cerebral blood flow and mean transit time: 5 s (p = 0.03) and 7 s (p < 0.0001), respectively. BT is not uncommon in stroke CTP with 40-s scan duration. Applying image down-sampling and VM improve tissue classification. (orig.)

Bolus versus continuous low dose of enalaprilat in congestive heart failure with acute refractory decompensation.

Science.gov (United States)

Podbregar, M; Voga, G; Horvat, M; Zuran, I; Krivec, B; Skale, R; Pareznik, R

1999-01-01

The first dose of angiotensin-converting enzyme (ACE) inhibitors may trigger a considerable fall of blood pressure in chronic heart failure. The response may be dose-related. To determine hemodynamic and systemic oxygenation effects of low-dose enalaprilat, we administered intravenous enalaprilat (0.004 mg/kg) as bolus (group B) or continuous 1-hour infusion (group C) in 20 patients with congestive heart failure due to ischemic heart disease with acute decompensation refractory to inotropic, vasodilator and diuretic therapy. Hemodynamic and systemic oxygenation variables were recorded at baseline (+0 min), +30, +60, +120, +180, and +360 min after the start of intervention. Mean arterial pressure (MAP) (p < 0. 001), mean pulmonary artery pressure (MPAP) (p < 0.001), pulmonary artery occlusion pressure (PAOP) (p < 0.001), oxygen extraction ratio (ER) (p < 0.026) decreased regardless of enalaprilat application. Compared to group B, there was in group C prolonged decrease of MAP, MPAP, PAOP, ER and increase of pulmonary artery oxyhemoglobin saturation in regard to baseline values. Cardiac index, heart rate, central venous pressure and oxygen consumption index did not change. A low dose of intravenous enalaprilat (0.004 mg/kg) can be used to safely improve hemodynamics and systemic oxygenation in congestive heart failure due to ischemic heart disease with acute refractory decompensation.

Plasma amino acids and metabolic profiling of dairy cows in response to a bolus duodenal infusion of leucine.

Science.gov (United States)

Sadri, Hassan; von Soosten, Dirk; Meyer, Ulrich; Kluess, Jeannette; Dänicke, Sven; Saremi, Behnam; Sauerwein, Helga

2017-01-01

Leucine (Leu), one of the three branch chain amino acids, acts as a signaling molecule in the regulation of overall amino acid (AA) and protein metabolism. Leucine is also considered to be a potent stimulus for the secretion of insulin from pancreatice β-cells. Our objective was to study the effects of a duodenal bolus infusion of Leu on insulin and glucagon secretion, on plasma AA concentrations, and to do a metabolomic profiling of dairy cows as compared to infusions with either glucose or saline. Six duodenum-fistulated Holstein cows were studied in a replicated 3 × 3 Latin square design with 3 periods of 7 days, in which the treatments were applied at the end of each period. The treatments were duodenal bolus infusions of Leu (DIL; 0.15 g/kg body weight), glucose (DIG; at Leu equimolar dosage) or saline (SAL). On the day of infusion, the treatments were duodenally infused after 5 h of fasting. Blood samples were collected at -15, 0, 10, 20, 30, 40, 50, 60, 75, 90, 120, 180, 210, 240 and 300 min relative to the start of infusion. Blood plasma was assayed for concentrations of insulin, glucagon, glucose and AA. The metabolome was also characterized in selected plasma samples (i.e. from 0, 50, and 120 min relative to the infusion). Body weight, feed intake, milk yield and milk composition were recorded throughout the experiment. The Leu infusion resulted in significant increases of Leu in plasma reaching 20 and 15-fold greater values than that in DIG and SAL, respectively. The elevation of plasma Leu concentrations after the infusion led to a significant decrease (Pcows were reduced (Pinsulin were not affected by Leu. In DIG, insulin and glucose concentrations peaked at 30-40 and 40-50 min after the infusion, respectively. Insulin concentrations were greater (Pcows were compared with the DIG and SAL cows at 50 and 120 min after the infusion. By using this analysis, several metabolites, mainly acylcarnitines, methionine sulfoxide and components from the

Computed tomography, after abdominal surgery

Energy Technology Data Exchange (ETDEWEB)

Vogel, H.; Toedt, H.C.

1985-09-01

The CT-examinations of 131 patients were analyzed after abdominal surgery. After nephrectomy, splenectomy, partial hepatectomy and pancreatectomy a displacement of the neighbouring intraabdominal and retroperitoneal organs was seen. Scar-tissue was observed containing fat, which faciltated the differential diagnosis to tumor recurrency. The changes of the roentgenmorphology were not so obvious after gastrointestinal surgery. After vascular surgery the permeability of an anastomosis or an operated artery could be demonstrated by bolus injection. (orig.).

GH receptor signaling in skeletal muscle and adipose tissue in human subjects following exposure to an intravenous GH bolus

DEFF Research Database (Denmark)

Jørgensen, Jens O L; Jessen, Niels; Pedersen, Steen Bønløkke

2006-01-01

Growth hormone (GH) regulates muscle and fat metabolism, which impacts on body composition and insulin sensitivity, but the underlying GH signaling pathways have not been studied in vivo in humans. We investigated GH signaling in biopsies from muscle and abdominal fat obtained 30 (n = 3) or 60 (n...... was measured by in vitro phosphorylation of PI. STAT5 DNA binding activity was assessed with EMSA, and the expression of IGF-I and SOCS mRNA was measured by real-time RT-PCR. GH induced a 52% increase in circulating FFA levels with peak values after 155 min (P = 0.03). Tyrosine-phosphorylated STAT5...... tended to increase after GH in muscle and fat, respectively. We conclude that 1) STAT5 is acutely activated in human muscle and fat after a GH bolus, but additional downstream GH signaling was significant only in fat; 2) the direct GH effects in muscle need further characterization; and 3) this human...

Computed tomography of hepatocellular carcinoma: Usefulness of dynamic CT

Energy Technology Data Exchange (ETDEWEB)

Takemoto, Kazumasa; Inoue, Yuichi; Matsuoka, Toshiyuki; Nakatsuka, Haruki; Oda, Junro [Osaka City Univ. (Japan). Faculty of Medicine

1983-04-01

Dynamic computed tomography (CT) scans in 65 hepatocellular carcinomas were analyzed and compared to plain and drip infusion contrast CT scans of those. Scans were obtained before, 10, 30, and 50 seconds after an intravenous bolus injection of 50ml 65% Angiografin. By this method, 49 hepatomas had moderate to marked enhancement at the arterial phase while the enhancement of normal liver parenchyma was only slight at the arterial phase and peaked at the portal phase. Compared to a drip infusion contrast CT, a dynamic CT had advantages to detect an isodense hepatoma in 4 and daughter tumors in 16 both of which were not appreciated by a plain and a drip infusion contrast CT. The tumor extension was also better delineated by a dynamic CT because a part of hepatoma had an isodense area. An arterio-portal shunt was visualized in one. Tumor thrombus in the portal vein was clearly demonstrated in 6 at the portal phase of a dynamic CT. Since a dynamic CT is convenient to perform without any special program or soft wear and gives us very useful information, we believe that it should be routinely employed as a part of a liver CT examination.

Revival and emended description of 'Mycobacterium paraffinicum' Davis, Chase and Raymond 1956 as Mycobacterium paraffinicum sp. nov., nom. rev.

Science.gov (United States)

Toney, Nadege; Adekambi, Toidi; Toney, Sean; Yakrus, Mitchell; Butler, W Ray

2010-10-01

The omission of the name 'Mycobacterium paraffinicum' from the Approved Lists of Bacterial Names was due to phenotypic confusion surrounding a close relationship with Mycobacterium scrofulaceum. Correspondingly, 'M. paraffinicum' strains grew slowly in > 7 days, stained acid-alcohol-fast and produced yellow-pigmented, smooth, waxy colonies in the dark at an optimal temperature of 35°C. However, 'M. paraffinicum' strains demonstrated no activity for urease, nicotinamidase or pyrazinamidase and lacked growth at 42°C, unlike M. scrofulaceum. The mycolic acid pattern, as determined by HPLC, clustered 'M. paraffinicum' with M. scrofulaceum, Mycobacterium avium and Mycobacterium parascrofulaceum. Strains were fully susceptible to linezolid, rifabutin, clarithromycin and amikacin. Examination of the historical reference strain of 'M. paraffinicum', ATCC 12670, and five additional isolates using comparative studies with 16S rRNA, hsp65 and rpoB gene and concatenated sequences showed that they formed a tight taxonomic group that was distinct from similar non-tuberculous mycobacteria. Multilocus enzyme electrophoresis (MEE) analysis confirmed a close association of the five additional isolates with the reference strain of 'M. paraffinicum' with a genetic distance of 0.12 and showed that all six strains were distinct from other closely related species. These genetic results provided unambiguous evidence of the uniqueness of this slowly growing, scotochromogenic species and supported the revival of the name as Mycobacterium paraffinicum (ex Davis, Chase and Raymond 1956) sp. nov., nom. rev. We propose the previously deposited reference strain ATCC 12670(T) =DSM 44181(T) =NCIMB 10420(T), located in collections worldwide, as the type strain.

Hepatic 123I-insulin binding kinetics in non-insulin-dependent (Type 2) diabetic patients after i.v. bolus administration

International Nuclear Information System (INIS)

Oolbekkink, M.; Veen, E.A. van der; Heine, R.J.; Hollander, W. den; Nauta, J.J.P.

1989-01-01

Insulin binding kinetics in the liver were studied in non insulin dependent (Type 2) diabetic patients, by i.v. bolus administration of 123 I-insulin. Eight Type 2 diabetic patients were compared with six male volunteers. Uptake of 123 I-insulin by liver and kidneys was measured by dynamic scintigraphy with a gamma camera during 30 min. Images of liver and kidneys appeared within 2-3 min after administration of 123 I-insulin at a dose of 1 mCi (37 MBq). Peak radioactivity for the liver was found 7.5±0.2 and 6.9±0.3 min after injection for the healthy and the diabetic subjects, respectively (N.S.). The percentage 123 I-insulin hepatic uptake was not significantly different for the diabetic and the healthy subjects. Although a large variation exists for maximal uptake of radioactivity within both groups, the data suggest that binding differences in the liver in Type 2 diabetic patients, as compared to healthy subjects, may not account for hepatic insulin resistance. (orig.)

Green Tea Increases the Concentration of Total Mercury in the Blood of Rats following an Oral Fish Tissue Bolus

Directory of Open Access Journals (Sweden)

Elsa M. Janle

2015-01-01

Full Text Available Fish has many health benefits but is also the most common source of methylmercury. The bioavailability of methylmercury in fish may be affected by other meal components. In this study, the effect of green tea on the bioavailability of methylmercury from an oral bolus of fish muscle tissue was studied in rats and compared to a water treated control group and a group treated with meso-2,3-dimercaptosuccinic acid (DMSA, a compound used medically to chelate mercury. Rats were given a single oral dose of fish tissue via gavage and one of the treatments. Rats were given access to food for 3 h at 12 h intervals. They were dosed with each of the treatments with each meal. Blood samples were collected for 95 hours. Green tea significantly increased the concentration of total mercury in blood relative to the control, whereas DMSA significantly decreased it. In addition, feeding caused a slight increase in blood mercury for several meals following the initial dose.

Chasing the limits of the one electron approximation

Energy Technology Data Exchange (ETDEWEB)

Kędziera, Dariusz [Department of Chemistry, Nicolaus Copernicus University, Gagarina 7, 87-100 Toruń (Poland); Mentel, Łukasz M. [Section of Theoretical Chemistry, VU University, Amsterdam (Netherlands)

2014-10-06

Rapid progress in the development of computational methods for quantum chemistry is not properly balanced by the development of basis sets. Even in the case of few-electron systems it is hard to find basis set which are able to reproduce the ECG benchmarks with the mhartree accuracy. In this paper we show early work on improvements of the basis sets for small atomic and molecular systems. As a starting point the ground state of lithium atom and the lowest states of lithium dimer will be investigated. The exploratory optimization of the exponents of primitive gaussians will be based on even tempered scheme combined with CISD method.

Dietary fat acutely increases glucose concentrations and insulin requirements in patients with type 1 diabetes: implications for carbohydrate-based bolus dose calculation and intensive diabetes management.

Science.gov (United States)

Wolpert, Howard A; Atakov-Castillo, Astrid; Smith, Stephanie A; Steil, Garry M

2013-04-01

Current guidelines for intensive treatment of type 1 diabetes base the mealtime insulin bolus calculation exclusively on carbohydrate counting. There is strong evidence that free fatty acids impair insulin sensitivity. We hypothesized that patients with type 1 diabetes would require more insulin coverage for higher-fat meals than lower-fat meals with identical carbohydrate content. We used a crossover design comparing two 18-h periods of closed-loop glucose control after high-fat (HF) dinner compared with low-fat (LF) dinner. Each dinner had identical carbohydrate and protein content, but different fat content (60 vs. 10 g). Seven patients with type 1 diabetes (age, 55 ± 12 years; A1C 7.2 ± 0.8%) successfully completed the protocol. HF dinner required more insulin than LF dinner (12.6 ± 1.9 units vs. 9.0 ± 1.3 units; P = 0.01) and, despite the additional insulin, caused more hyperglycemia (area under the curve >120 mg/dL = 16,967 ± 2,778 vs. 8,350 ± 1,907 mg/dL⋅min; P Carbohydrate-to-insulin ratio for HF dinner was significantly lower (9 ± 2 vs. 13 ± 3 g/unit; P = 0.01). There were marked interindividual differences in the effect of dietary fat on insulin requirements (percent increase significantly correlated with daily insulin requirement; R(2) = 0.64; P = 0.03). This evidence that dietary fat increases glucose levels and insulin requirements highlights the limitations of the current carbohydrate-based approach to bolus dose calculation. These findings point to the need for alternative insulin dosing algorithms for higher-fat meals and suggest that dietary fat intake is an important nutritional consideration for glycemic control in individuals with type 1 diabetes.

Regional cerebral blood flow measurement with intravenous [15O]water bolus and [18F]fluoromethane inhalation

International Nuclear Information System (INIS)

Herholz, K.; Pietrzyk, U.; Wienhard, K.; Hebold, I.; Pawlik, G.; Wagner, R.; Holthoff, V.; Klinkhammer, P.; Heiss, W.D.

1989-01-01

In 20 patients with ischemic cerebrovascular disease, classic migraine, or angiomas, we compared paired dynamic positron emission tomographic measurements of regional cerebral blood flow using both [ 15 O]water and [ 18 F]fluoromethane as tracers. Cerebral blood flow was also determined according to the autoradiographic technique with a bolus injection of [ 15 O]water. There were reasonable overall correlations between dynamic [ 15 O]water and [ 18 F]fluoromethane values for cerebral blood flow (r = 0.82) and between dynamic and autoradiographic [ 15 O]water values for cerebral blood flow (r = 0.83). We found a close correspondence between abnormal pathologic findings and visually evaluated cerebral blood flow tomograms obtained with the two tracers. On average, dynamic [ 15 O]water cerebral blood flow was 6% lower than that measured with [ 18 F]fluoromethane. There also was a general trend toward a greater underestimation with [ 15 O]water in high-flow areas, particularly in hyperemic areas, probably due to incomplete first-pass extraction of [ 15 O]water. Underestimation was not detected in low-flow areas or in the cerebellum. Absolute cerebral blood flow values were less closely correlated between tracers and techniques than cerebral blood flow patterns. The variability of the relation between absolute flow values was probably caused by confounding effects of the variation in the circulatory delay time. The autoradiographic technique was most sensitive to this type error

Ionic and non-ionic contrast media used for contrast-enhanced computed tomography in experimental pancreatitis

International Nuclear Information System (INIS)

Kivisaari, L.; Nuutinen, P.; Lehtola, A.; Saari, A.; Pitkaeranta, P.; Standertskjoeld-Nordenstam, C.G.; Lempinen, M.; Schroeder, T.; Helsinki Univ. Central Hospital

1988-01-01

Contrast enhancement of the pancreas was studied in pigs using dynamic computed tomography in experimental oedematous and haemorrhagic/necrotizing pancreatitis during the first two minutes after injection of an intravenous bolus of non-ionic contrast medium (iohexol). The prospects of separating the two forms of the disease, known to be possible with ionic contrast media, were tested with a non-ionic contrast medium. In the oedematous form, contrast enhancement after 5 hours of the disease was significantly higher than in the haemorrhagic/necrotizing form. Contrast enhancement after 30 hours of disease tended to vary with the severity of the disease, showing that the course of oedematous pancreatitis is dynamic. Intermediate forms occur and follow-up studies are needed during the disease. A non-ionic contrast medium proved as good for separating the two forms of the disease in the early phase as were ionic contrast media. In severely ill patients, non-ionic contrast media should therefore be used. (orig.)

Cerebral hemodynamic changes measured by gradient-echo or spin-echo bolus tracking and its correlation to changes in ICA blood flow measured by phase-mapping MRI

DEFF Research Database (Denmark)

Marstrand, J.R.; Rostrup, Egill; Garde, Ellen

2001-01-01

Changes in cerebral blood flow (CBF) induced by Acetazolamide (ACZ) were measured using dynamic susceptibility contrast MRI (DSC-MRI) with both spin echo (SE) EPI and gradient echo (GE) EPI, and related to changes in internal carotid artery (ICA) flow measured by phase-mapping. Also examined...... increase in CBF and CBV in response to ACZ, while SE-EPI measured a significant increase in CBV and MTT. CBV and MTT change measured by SE-EPI was sensitive to previous bolus injections. There was a significant linear relation between change in CBF measured by GE-EPI and change in ICA flow. In conclusion......, GE-EPI under the present condition was superior to SE-EPI in monitoring cerebral vascular changes...

Reproducibility of 5-HT2A receptor measurements and sample size estimations with [18F]altanserin PET using a bolus/infusion approach

DEFF Research Database (Denmark)

Haugbøl, Steven; Pinborg, Lars H; Arfan, Haroon M

2006-01-01

PURPOSE: To determine the reproducibility of measurements of brain 5-HT2A receptors with an [18F]altanserin PET bolus/infusion approach. Further, to estimate the sample size needed to detect regional differences between two groups and, finally, to evaluate how partial volume correction affects...... reproducibility and the required sample size. METHODS: For assessment of the variability, six subjects were investigated with [18F]altanserin PET twice, at an interval of less than 2 weeks. The sample size required to detect a 20% difference was estimated from [18F]altanserin PET studies in 84 healthy subjects....... Regions of interest were automatically delineated on co-registered MR and PET images. RESULTS: In cortical brain regions with a high density of 5-HT2A receptors, the outcome parameter (binding potential, BP1) showed high reproducibility, with a median difference between the two group measurements of 6...

Comparison the effect of two ways of tube feeding including bolus and continuous infusion on gastric residual volume and diarrhea in patients hospitalized in Intensive Care Unit

Directory of Open Access Journals (Sweden)

Shahriari M

2015-05-01

Full Text Available Background and Objective: Proper nutritional support is one of the important caring aspects in patients who were hospitalized in Intensive Care Unit. Although the several studies have been done concerning the selection of proper nutrition method for patients, but there is no agreement on this issue. The aim of current study was the compare the effect of two ways of tube feeding including bolus and continuous infusion on gastric residual volume and diarrhea in patients hospitalized in Intensive Care Unit.  Materials and Method: The current clinical trial was conducted on patients who were hospitalized in intensive care unit in Alzahra hospital in Isfahan, 2013. Fifty patients were selected through convenient sampling and were randomly assigned into two groups of 25 people of intervention and control. Nutrition was done through infusion pump in intervention group and by bolus in control group. Gastric residual volume and diarrhea was assessed each four hours for four days. Data were gathered through checklist and were analyzed by SPSS18 using descriptive and inferential statistics including independent T-test, Fisher's exact test and repeated measures ANOVA.  Results: The results showed that the mean of gastric residual volume in control group was more than the intervention group on the third day (p=0.04. Also, the mean of gastric residual volume did not show significant difference at different times in intervention group, but the mean of gastric residual volume was significantly increased in control group at different times (p=0.04. Fisher's exact test showed no significant difference between two groups concerning the diarrhea frequency.  Conclusion: In nutritional support with continuous infusion method, gastric residual volume was not increased and gastric emptying rate was not diminished. Therefore, this method can be used as an appropriate nutritional support in intensive care unit.

Study of the dose to the thyroid and the eye in computed tomography of the brain

International Nuclear Information System (INIS)

Raeside, D.E.; Anderson, D.W.; Galloway, D.C.

1978-01-01

Thermoluminescent doimeters were used to estimate the dose to the thyroid and the eye for routine clinical computer tomography of the brain using an EMI CT 5005 scanner (20-sec data acquisition mode, bolus covering the head). The data can be summarized by the linear relations D/sub t/ = (7.5 +- 0.8)N millirads (8 less than or equal to N less than or equal to 18) and D/sub e/ = (39 +- 5)N + (1400 +- 200)n millirads (8 less than or equal to N less than or equal to 20,0 less than or equal to n less than or equal to 6) where D/sub t/ is the dose to the tissue anterior to the thyroid, D/sub e/ is the dose to the anterior tissue of the eyelid, N is the total number of DT cuts, and n is the number of cuts in which the globe of the eye is imaged

Feasibility of power contrast injections and bolus triggering during CT scans in oncologic patients with totally implantable venous access ports of the forearm

International Nuclear Information System (INIS)

Goltz, Jan Peter; Machann, Wolfram; Noack, Claudia; Hahn, Dietbert; Kickuth, Ralph

2011-01-01

Background: Conventional totally implantable venous access ports (TIVAPs) are not approved for power contrast injections but often remain the only venous access site in oncologic patients. Therefore, these devices can play an important role if patients with a TIVAP are scheduled for a contrast-enhanced computed tomography (ceCT) as vascular access may become more difficult during the course of chemotherapy. Purpose: To evaluate the feasibility and safety of power injections in conventional TIVAPs in the forearm and to analyze the feasibility of bolus triggering during CT scans. Material and Methods: In this retrospective study we analyzed 177 power injections in 141 patients with TIVAPs in the forearm. Between October 2008 and March 2010 all patients underwent power injections (1.5 mL/s, 150 psi) via the TIVAP for ceCT because conventional vascular access via a peripheral vein had failed. Adequate functioning and catheter's tip location after injection were evaluated. Peak injection pressure and attenuation levels of aorta, liver and spleen were analyzed and compared with results of 50 patients who were injected via classical peripheral cannulas (3 mL/s, 300 psi). Feasibility of automatic scan initiation was evaluated. In vitro the port was stressed with 5 mL/s (300 psi). Results: One TIVAP showed tip dislocation with catheter rupture. Three (2.1%) devices were explanted owing to assumed infection within 4 weeks after the injection. Mean injection pressure was 121.9 ±24.1 psi. Triggering with automatic scan initiation succeeded in 13/44 (29.6%) scans. Injection via classical cannulas resulted in significantly higher enhancement (p < 0.05). In vitro the port system tolerated flow rates of up to 5 mL/s, injection pressures of up to 338 psi. Conclusion: Power injection is a safe alternative for patients with TIVAPs in the forearm if classic vascular access ultimately fails. Triggering was successful in one-third of the attempts. Image quality in the arterial phase

Improving the management of diabetes in hospitalized patients: the results of a computer-based house staff training program.

Science.gov (United States)

Vaidya, Anand; Hurwitz, Shelley; Yialamas, Maria; Min, Le; Garg, Rajesh

2012-07-01

Poorly controlled diabetes in hospitalized patients is associated with poor clinical outcomes. We hypothesized that computer-based diabetes training could improve house staff knowledge and comfort for the management of diabetes in a large tertiary-care hospital. We implemented a computer-based training program on inpatient diabetes for internal medicine house staff at the Brigham and Women's Hospital (Boston, MA) in September 2009. House staff were required to complete the program and answer a set of questions, before and after the program, to evaluate their level of comfort and knowledge of inpatient diabetes. Chart reviews of all non-critically ill patients with diabetes managed by house staff in August 2009 (before the program) and December 2009 (after the program) were performed. Chart reviews were also performed for August 2008 and December 2008 to compare house staff management practices when the computer-based educational program was not available. A significant increase in comfort levels and knowledge in the management of inpatient diabetes was seen among house staff at all levels of training (Pstaff compared with junior house staff. Nonsignificant trends suggesting increased use of basal-bolus insulin (P=0.06) and decreased use of sliding-scale insulin (P=0.10) were seen following the educational intervention in 2009, whereas no such change was seen in 2008 (P>0.90). Overall, house staff evaluated the training program as "very relevant" and the technology interface as "good." A computer-based diabetes training program can improve the comfort and knowledge of house staff and potentially improve their insulin administration practices at large academic centers.

EVALUATION OF PHYTOTOXIC EFFECT OF DELETERIOUS RHIZOBACTERIA ON THE ROOT GROWTH OF AXONOPUS AFFINIS (CHASE AND LENS ESCULENTA (MOENCH

Directory of Open Access Journals (Sweden)

X.J Pacheco-Hernández

2015-11-01

Full Text Available Las malezas ocasionan una gran pérdida en las tierras agrícolas y comúnmente, las medidas de manejo y contención de estas especies se dan con la aplicación de herbicidas, sin embargo; en años recientes se ha presentado un interés en establecer mecanismos de biocontrol seguros, con el empleo de bacterias inhibidoras del crecimiento conocidas como rizobacterias deletéreas (Deleterious rhizobacteria: DRBque se consideran generalmente como no parasíticas, y causan, de manera sutil, efectos deletéreos a través de la producción de metabolitos dañinos a las plantas. El presente trabajo tuvo como objetivo caracterizar la producción de ácido cianhídrico de pseudomonas rizobacterianas de malezas de un cultivo de alfalfa (Medicago sativa L. y evaluar el efecto fitotóxico de éstas sobre el crecimiento radical de plántulas de Axonopus affinis (Chase y Lens esculenta (Moench. De acuerdo con los resultados obtenidos con relación a la evidencia de que los aislados de pseudomonadas son rizobacterias cianogénicas y de su efecto fitotóxico medido sobre las especies vegetales bajo estudio; se sugieren a éstas como posibles agentes de biocontrol con pastos que sean considerados malezas; ya que en general se observó que inhiben su crecimiento radical; sin embargo, un enfoque particular lo tiene la rizobacteria Pseudomonas sp. A52, la cual presentó no solamente actividad como una DRB sino también como una rizobacteria promotora del crecimiento vegetal; lo que la hace más importante de analizar en cuanto a su potencial y espectro de acción; tanto para malezas monocotiledóneas como para dicotiledóneas, recomendable como un posible agente de biocontrol con actividad múltiple.

Contrast-enhanced peripheral MRA. Technique and contrast agents

International Nuclear Information System (INIS)

Nielsen, Yousef W.; Thomsen, Henrik S.

2012-01-01

In the last decade contrast-enhanced magnetic resonance angiography (CE-MRA) has gained wide acceptance as a valuable tool in the diagnostic work-up of patients with peripheral arterial disease. This review presents current concepts in peripheral CE-MRA with emphasis on MRI technique and contrast agents. Peripheral CE-MRA is defined as an MR angiogram of the arteries from the aortic bifurcation to the feet. Advantages of CE-MRA include minimal invasiveness and lack of ionizing radiation. The basic technique employed for peripheral CE-MRA is the bolus-chase method. With this method a paramagnetic MRI contrast agent is injected intravenously and T1-weighted images are acquired in the subsequent arterial first-pass phase. In order to achieve high quality MR angiograms without interfering venous contamination or artifacts, a number of factors need to be taken into account. This includes magnetic field strength of the MRI system, receiver coil configuration, use of parallel imaging, contrast bolus timing technique, and k-space filling strategies. Furthermore, it is possible to optimize peripheral CE-MRA using venous compression techniques, hybrid scan protocols, time-resolved imaging, and steady-state MRA. Gadolinium(Gd)-based contrast agents are used for CE-MRA of the peripheral arteries. Extracellular Gd agents have a pharmacokinetic profile similar to iodinated contrast media. Accordingly, these agents are employed for first-pass MRA. Blood-pool Gd-based agents are characterized by prolonged intravascular stay, due to macromolecular structure or protein binding. These agents can be used for first-pass, as well as steady-state MRA. Some Gd-based contrast agents with low thermodynamic stability have been linked to development of nephrogenic systemic fibrosis in patients with severe renal insufficiency. Using optimized technique and a stable MRI contrast agent, peripheral CE-MRA is a safe procedure with diagnostic accuracy close to that of conventional catheter X

Plasma free amino acid kinetics in rainbow trout (Oncorhynchus mykiss) using a bolus injection of 15N-labeled amino acids.

Science.gov (United States)

Robinson, Jacob William; Yanke, Dan; Mirza, Jeff; Ballantyne, James Stuart

2011-02-01

To gain insight into the metabolic design of the amino acid carrier systems in fish, we injected a bolus of (15)N amino acids into the dorsal aorta in mature rainbow trout (Oncorhynchus mykiss). The plasma kinetic parameters including concentration, pool size, rate of disappearance (R(d)), half-life and turnover rate were determined for 15 amino acids. When corrected for metabolic rate, the R(d) values obtained for trout for most amino acids were largely comparable to human values, with the exception of glutamine (which was lower) and threonine (which was higher). R(d) values ranged from 0.9 μmol 100 g(-1) h(-1) (lysine) to 22.1 μmol 100 g(-1) h(-1) (threonine) with most values falling between 2 and 6 μmol 100 g(-1) h(-1). There was a significant correlation between R(d) and the molar proportion of amino acids in rainbow trout whole body protein hydrolysate. Other kinetic parameters did not correlate significantly with whole body amino acid composition. This indicates that an important design feature of the plasma-free amino acids system involves proportional delivery of amino acids to tissues for protein synthesis.

Individual renal function study using dynamic computed tomography

International Nuclear Information System (INIS)

Fukuda, Yutaka; Kiya, Keiichi; Suzuki, Yoshiharu

1990-01-01

Dynamic CT scans of individual kindneys were obtained after an intravenous bolus injection of contrast agent. Time-density curves measured from the renal cortex, medulla and pelvis revealed the changes in density produced by the contrast agent reflecting the differential phase of renal function. Renal cortical density increased rapidly after bolus administration and then renal medullary and pelvic density increased continuously. In analyzing time-density curve, the cortico-medullary junction time, which is the time when the cortical and medullary curves cross was 57±8 seconds in patients with normal renal function. The cortico-medullary junction time was delayed in patient with decreased glomerular filtration rate. The cortico-pelvic junction time, which is the time when the cortical and pelvic curves cross was 104±33 seconds in patients with normal renal function. The cortico-pelvic junction time was delayed in patients with declined urinary concentrating capacity. In patients with unilateral renal agenesis and patients who were treated surgically by ureteral sprits, the relationship between individual renal functions and these junction times was examined. As a result of study there were inversely significant correlations between C-M junction time and unilateral GFR and between C-P junction time and urinary concentrating capacity. These studies indicate that dynamic CT scanning is an effective way that individual renal function can be monitored and evaluated. (author)

Insulin Administration for People with Type 1 diabetes

DEFF Research Database (Denmark)

Boiroux, Dimitri; Finan, Daniel Aaron; Poulsen, Niels Kjølstad

2011-01-01

considers meal announcement at mealtimes only. They give a quantitative upper bound on the achievable control performance. The third control strategy is a feedforward-feedback control strategy. This strategy uses a time-varying setpoint to reduce the risk of hypoglycemia. The feedback controller computes......In this paper, we apply model predictive control (MPC) for control of blood glucose in people with type 1 diabetes. The two first control strategies are based on nonlinear model predictive control (NMPC). The first control strategy is based on meal announcement in advance, while the second one...... the optimal basal insulin infusion rate. The feedforward controller consists of a bolus calculator. It computes the optimal bolus, along with the time-varying glucose setpoint. We test these three strategies on a virtual patient with type 1 diabetes. The numerical results demonstrate the robustness...

Turnover in intracranial aneurysm phantoms: its relation to neck size

International Nuclear Information System (INIS)

Chung, Tae Sub; Lee, Young Jun; Rhim, Yoon Chul

2003-01-01

To evaluate the physiologic background of aneurysms poorly visualized during 3D-TOF MRA, contrast-enhanced MRA (CEMRA) and DSA due to hemodynamic isolation. Using handmade elastic silicon phantoms to represent terminal basilar tip aneurysms, 3D-TOF MRA, CEMRA and DSA were used to determine blood turnover. Aneurysmal neck size was 2 mm and 10 mm, and the use of a pulsatile pump also helped recreate human physiologic parameters. We compared the results with those of computational fluid dynamics. DSA images of the narrow-necked aneurysm showed that a small volume of contrast medium washed into it during the systolic phase. As the width of its neck increased, the turnover volume of fragments of contrast bolus also increased. At CEMRA, the broad-necked aneurysm was visualized as the main bolus of Gd-DTPA passed through it, and at delayed CEMRA, the narrow-necked aneurysm was visualized faintly after the passage of bolus Gd-DTPA. The results correlated closely with those of 3D-TOF MRA and computational fluid dynamics. The visualization of intracranial aneurysms at 3D-TOF MRA, CEMRA and DSA was greatly dependent upon blood turnover, which varied according to aneurysmal neck size. A narrow-necked aneurysm might be missed at 3D-TOF MRA, CEMRA and DSA due to hemodynamic isolation

CHASE '10

DEFF Research Database (Denmark)

Software is created by people---software engineers---working in varied environments, under various conditions. Thus understanding cooperative and human aspect of software development is crucial to comprehend how methods and tools are used, and thereby improving the creation and maintenance of sof...

Chasing volatility

DEFF Research Database (Denmark)

Caporin, Massimiliano; Rossi, Eduardo; Santucci de Magistris, Paolo

The realized volatility of financial returns is characterized by persistence and occurrence of unpreditable large increments. To capture those features, we introduce the Multiplicative Error Model with jumps (MEM-J). When a jump component is included in the multiplicative specification, the condi......The realized volatility of financial returns is characterized by persistence and occurrence of unpreditable large increments. To capture those features, we introduce the Multiplicative Error Model with jumps (MEM-J). When a jump component is included in the multiplicative specification...... estimate alternative specifications of the model using a set of daily bipower measures for 7 stock indexes and 16 individual NYSE stocks. The estimates of the jump component confirm that the probability of jumps dramatically increases during the financial crisis. Compared to other realized volatility...... models, the introduction of the jump component provides a sensible improvement in the fit, as well as for in-sample and out-of-sample volatility tail forecasts....

Knowledge Translation to Optimize Adult Inpatient Glycemic Management with Basal Bolus Insulin Therapy and Improve Patient Outcomes.

Science.gov (United States)

Helmle, Karmon E; Chacko, Sunita; Chan, Trevor; Drake, Alison; Edwards, Alun L; Moore, Glenda E; Philp, Leta C; Popeski, Naomi; Roedler, Rhonda L; Rogers, Edwin J R; Zimmermann, Gabrielle L; McKeen, Julie

2017-12-27

To develop and evaluate a Basal Bolus Insulin Therapy (BBIT) Knowledge Translation toolkit to address barriers to adoption of established best practice with BBIT in the care of adult inpatients. This study was conducted in 2 phases and focused on the hospitalist provider group across 4 acute care facilities in Calgary. Phase 1 involved a qualitative evaluation of provider and site specific barriers and facilitators, which were mapped to validated interventions using behaviour change theory. This informed the co-development and optimization of the BBIT Knowledge Translation toolkit, with each tool targeting a specific barrier to improved diabetes care practice, including BBIT ordering. In Phase 2, the BBIT Knowledge Translation toolkit was implemented and evaluated, focusing on BBIT ordering frequency, as well as secondary outcomes of hyperglycemia (patient-days with BG >14.0 mmol/L), hypoglycemia (patient-days with BG Knowledge Translation toolkit resulted in a significant 13% absolute increase in BBIT ordering. Hyperglycemic patient-days were significantly reduced, with no increase in hypoglycemia. There was a significant, absolute 14% reduction in length of stay. The implementation of an evidence-informed, multifaceted BBIT Knowledge Translation toolkit effectively reduced a deeply entrenched in-patient diabetes care gap. The resulting sustained practice change improved patient clinical and system resource utilization outcomes. This systemic approach to implementation will guide further scale and spread of glycemic optimization initiatives. Copyright © 2018 Diabetes Canada. Published by Elsevier Inc. All rights reserved.

Comparison of first pass bolus AIFs extracted from sequential 18F-FDG PET and DSC-MRI of mice

International Nuclear Information System (INIS)

Evans, Eleanor; Sawiak, Stephen J.; Ward, Alexander O.; Buonincontri, Guido; Hawkes, Robert C.; Adrian Carpenter, T.

2014-01-01

Accurate kinetic modelling of in vivo physiological function using positron emission tomography (PET) requires determination of the tracer time–activity curve in plasma, known as the arterial input function (AIF). The AIF is usually determined by invasive blood sampling methods, which are prohibitive in murine studies due to low total blood volumes. Extracting AIFs from PET images is also challenging due to large partial volume effects (PVE). We hypothesise that in combined PET with magnetic resonance imaging (PET/MR), a co-injected bolus of MR contrast agent and PET ligand can be tracked using fast MR acquisitions. This protocol would allow extraction of a MR AIF from MR contrast agent concentration–time curves, at higher spatial and temporal resolution than an image-derived PET AIF. A conversion factor could then be applied to the MR AIF for use in PET kinetic analysis. This work has compared AIFs obtained from sequential DSC-MRI and PET with separate injections of gadolinium contrast agent and 18 F-FDG respectively to ascertain the technique′s validity. An automated voxel selection algorithm was employed to improve MR AIF reproducibility. We found that MR and PET AIFs displayed similar character in the first pass, confirmed by gamma variate fits (p<0.02). MR AIFs displayed reduced PVE compared to PET AIFs, indicating their potential use in PET/MR studies

A minimal model of predator-swarm interactions.

Science.gov (United States)

Chen, Yuxin; Kolokolnikov, Theodore

2014-05-06

We propose a minimal model of predator-swarm interactions which captures many of the essential dynamics observed in nature. Different outcomes are observed depending on the predator strength. For a 'weak' predator, the swarm is able to escape the predator completely. As the strength is increased, the predator is able to catch up with the swarm as a whole, but the individual prey is able to escape by 'confusing' the predator: the prey forms a ring with the predator at the centre. For higher predator strength, complex chasing dynamics are observed which can become chaotic. For even higher strength, the predator is able to successfully capture the prey. Our model is simple enough to be amenable to a full mathematical analysis, which is used to predict the shape of the swarm as well as the resulting predator-prey dynamics as a function of model parameters. We show that, as the predator strength is increased, there is a transition (owing to a Hopf bifurcation) from confusion state to chasing dynamics, and we compute the threshold analytically. Our analysis indicates that the swarming behaviour is not helpful in avoiding the predator, suggesting that there are other reasons why the species may swarm. The complex shape of the swarm in our model during the chasing dynamics is similar to the shape of a flock of sheep avoiding a shepherd.

Significance of computed tomography in urology

International Nuclear Information System (INIS)

Harada, Takashi

1981-01-01

There are more than five years since computed tomography (CT) was first introduced in this country for practical use. However, cumulative diagnostic experiences in urology have not been discussed thoroughly yet. In the Department of Urology of Kansai Medical University over 120 times CT diagnosis were attempted past three years and the instrument employed during this period has been alternative from the first generation type (ACTA 150) to the third one (CT-3W) this year as to technical advance. These cases are 70 of pelvic lesions and retroperitoneal surveys are made in the rests. As a results, detection of space occupying mass in kidney, adrenal and their surroundings was comparatively easy to deliver by this method, but there are several pitfalls to come misunderstanding in diagnosis of pelvic organs. It seems to be difficult to obtain certain result on closely packed viscera with tightly adhered connective tissue in tiny space. However, these difficulties will be solved by bladder insufflation with olive oil, for instance, and scanning in prone position. Contrast enhancement by injection of dye also give more definite results in genitourinary tract assessment. Moreover, there are much benefit in diagnosis of renal parenchymal change including lacerating renal trauma unable to be differentiated conventional method. Bolus injection of contrast material also allows to calculate CT values obtained from ROI on tomography and enables to fit the value to time-activity curve likewise scintillation scanning. In forthcomming day, new device in this field including emission-CT, NMR-CT and others will open new sight for ideal diagnostic facility in urology. (author)

Application of Failure Mode Effect and Criticality Analysis (FMECA to a Computer Integrated Manufacturing (CIM Conveyor Belt

Directory of Open Access Journals (Sweden)

I. Elbadawi

2018-06-01

Full Text Available Fault finding and failure predicting techniques in manufacturing and production systems often involve forecasting failures, their effects, and occurrences. The majority of these techniques predict failures that may appear during the regular system production time. However, they do not estimate the failure modes and they require extensive source code instrumentation. In this study, we suggest an approach for predicting failure occurrences and modes during system production time intervals at the University of Hail (UoH. The aim of this project is to implement failure mode effect and criticality analysis (FMECA on computer integrated manufacturing (CIM conveyors to determine the effect of various failures on the CIM conveyor belt by ranking and prioritizing each failure according to its risk priority number (RPN. We incorporated the results of FMECA in the development of formal specifications of fail-safe CIM conveyor belt systems. The results show that the highest RPN values are for motor over current failure (450, conveyor chase of vibration (400, belt run off at the head pulley (200, accumulated dirt (180, and Bowed belt (150. The study concludes that performing FMECA is highly effective in improving CIM conveyor belt reliability and safety in the mechanical engineering workshop at UoH.

A proposal to study the esophageal transit by biomagnetic and scintigraphic study; Uma nova proposta para o estudo do transito esofagiano atraves das tecnicas biomagneticas e cintilograficas

Energy Technology Data Exchange (ETDEWEB)

Daghastanli, N.A.; Braga, F.J.H.N.; Baffa, O. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Filosofia, Ciencias e Letras. Dept. de Fisica; Oliveira, R.B. [Faculdade de Medicina de Ribeirao Preto, SP (Brazil)

1996-12-31

The initial results for a new apparatus to study the esophageal transit time is studied in asymptomatic persons for a yogurt bolus (10 ml). The bolus is uniformly labeled with 5 g of ferrite powder (biomagnetic study, B) or 350 MBq of {sup 99m} Tc (scintigraphic study, C). For the B study the detection is made by means two pair of coils in opposite phase excited by a 10 k Hz sinusoidal voltage. The signal response is obtained when the bolus traverses the coils placed on the regions-of-interest (ROIs) of the esophagus (furcula, F and xiphoid process, X) and produces a signal voltage that is measured by a lock-in amplifier Stanford SR530. For C studies an Orbiter Siemens scintillation camera is used linked to a computer. The data analysis shows a (4.1{+-}0.7)s in B studies and (3.7{+-}0.9)s in C studies (R=0.6, P<0.07) 8 refs., 3 figs.

A proposal to study the esophageal transit by biomagnetic and scintigraphic study

International Nuclear Information System (INIS)

Daghastanli, N.A.; Braga, F.J.H.N.; Baffa, O.

1996-01-01

The initial results for a new apparatus to study the esophageal transit time is studied in asymptomatic persons for a yogurt bolus (10 ml). The bolus is uniformly labeled with 5 g of ferrite powder (biomagnetic study, B) or 350 MBq of 99m Tc (scintigraphic study, C). For the B study the detection is made by means two pair of coils in opposite phase excited by a 10 k Hz sinusoidal voltage. The signal response is obtained when the bolus traverses the coils placed on the regions-of-interest (ROIs) of the esophagus (furcula, F and xiphoid process, X) and produces a signal voltage that is measured by a lock-in amplifier Stanford SR530. For C studies an Orbiter Siemens scintillation camera is used linked to a computer. The data analysis shows a (4.1±0.7)s in B studies and (3.7±0.9)s in C studies (R=0.6, P<0.07)

Chase the direct impact of rainfall into groundwater in Mt. Fuji from multiple analyses including microbial DNA

Science.gov (United States)

Kato, Kenji; Sugiyama, Ayumi; Nagaosa, Kazuyo; Tsujimura, Maki

2016-04-01

A huge amount of groundwater is stored in subsurface environment of Mt. Fuji, the largest volcanic mountain in Japan. Based on the concept of piston flow transport of groundwater an apparent residence time was estimated to ca. 30 years by 36Cl/Cl ratio (Tosaki et al., 2011). However, this number represents an averaged value of the residence time of groundwater which had been mixed before it flushes out. We chased signatures of direct impact of rainfall into groundwater to elucidate the routes of groundwater, employing three different tracers; stable isotopic analysis (delta 18O), chemical analysis (concentration of silica) and microbial DNA analysis. Though chemical analysis of groundwater shows an averaged value of the examined water which was blended by various water with different sources and routes in subsurface environment, microbial DNA analysis may suggest the place where they originated, which may give information of the source and transport routes of the water examined. Throughout the in situ observation of four rainfall events showed that stable oxygen isotopic ratio of spring water and shallow groundwater obtained from 726m a.s.l. where the average recharge height of rainfall was between 1500 and 1800 m became higher than the values before a torrential rainfall, and the concentration of silica decreased after this event when rainfall exceeded 300 mm in precipitation of an event. In addition, the density of Prokaryotes in spring water apparently increased. Those changes did not appear when rainfall did not exceed 100 mm per event. Thus, findings shown above indicated a direct impact of rainfall into shallow groundwater, which appeared within a few weeks of torrential rainfall in the studied geological setting. In addition, increase in the density of Archaea observed at deep groundwater after the torrential rainfall suggested an enlargement of the strength of piston flow transport through the penetration of rainfall into deep groundwater. This finding was

Contrast Media Delivery in the Assessment of Anomalous Left Coronary Artery From the Pulmonary Artery.

Science.gov (United States)

Saade, Charbel; Al-Hamra, Salam; Al-Mohiy, Hussain; El-Merhi, Fadi

2016-05-01

A patient with a history of mitral valve prolapse and regurgitation that was corrected with a mitral ring repair 15 years earlier received a diagnosis of anomalous left coronary artery arising from the pulmonary artery and underwent repair. Coronary computed tomography angiography (CTA) was employed to image the patient before surgical intervention. Synchronizing contrast media administration to opacify the right coronary artery in the arterial phase and the left coronary artery in the venous phase required a test-bolus approach. Matching compromised cardiovascular dynamics with patient-specific contrast media administration protocols was improved considerably with the use of a test-bolus technique during electrocardiography-gated coronary CTA.

CT Angiography of Peripheral Arterial Disease by 256-Slice Scanner: Accuracy, Advantages and Disadvantages Compared to Digital Subtraction Angiography.

Science.gov (United States)

Mishra, Atul; Jain, Narendra; Bhagwat, Anand

2017-07-01

Peripheral arterial occlusive disease (PAOD) may cause disabling claudication or critical limb ischemia. Multidetector computed tomography (CT) technology has evolved to the level of 256-slice CT scanners which has significantly improved the spatial and temporal resolution of the images. This has provided the capability of chasing the contrast bolus at a fast speed enabling angiographic imaging of long segments of the body. These images can be reconstructed in various planes and various modes for detailed analysis of the peripheral vascular diseases which helps in making treatment decision. The aim of this retrospective study was to compare the CT angiograms (CTAs) of all cases of PAOD done by 256-slice CT scanner at a tertiary care vascular center and comparing these images with the digital subtraction angiograms (DSAs) of these patients. The retrospective study included 53 patients who underwent both CTA and DSA at our center over a period of 3 years from March 2013 to March 2016. The CTA showed high sensitivity (93%) and specificity (92.7%) for overall assessment of degree of stenosis in a vascular segment in cases of aortic and lower limb occlusive disease. The assessment of lesions of infrapopliteal segment was comparatively inferior (sensitivity 91.6%, accuracy 73.3%, and positive predictive value 78.5%), more so in the presence of significant calcification. The advantages of CTA were its noninvasive nature, ability to image large area of body, almost no adverse effects to the patients, and better assessment of vessel wall disease. However, the CTA assessment of collaterals was inferior with a sensitivity of only 62.7% as compared to DSA. Overall, 256-slice CTA provides fast and accurate imaging of vascular tree which can restrict DSA only in few selected cases as a problem-solving tool where clinico-radiological mismatch is present.

Observation of the CSF pulsatile flow in the aqueduct using cine MRI with presaturation bolus tracking, 3

International Nuclear Information System (INIS)

Nakajima, Satoshi

1992-01-01

The to-and-fro motion patterns of the CSF flow in the aqueduct in ten normal adults, ten patients with secondary normal-pressure hydrocephalus (NPH), and fourteen patients with idiopathic ventriculomegaly were analyzed using cine MRI with presaturation bolus tracking. The to-and-fro motion patterns of the CSF flow in the aqueduct were thus classified into four types according to their maximum velocity and the relative time duration of their flow in the rostral and caudal directions. The correlation between the clinical symptoms, the CT findings, the RI-cisternography findings, the results of the ICP monitorings, and the CSF pulsatile-flow patterns were then analyzed. In secondary NPH disclosing frequent B waves on ICP monitoring, the maximum velocity of the CSF flow in the aqueduct was over 15 mm/sec, and the duration of the CSF flow was longer in the caudal direction than in the rostral direction. Furthermore, the faster the maximum velocity of the CSF flow, the larger the ventricular size on CT and the more severe the CSF malabsorption on cisternography. In idiopathic ventriculomegaly, only two cases demonstrated the same CSF flow pattern as was shown in secondary NPH; the other cases demonstrated other CSF flow patterns, which were considered to indicate hydrocephalus ex vacuo or arrested hydrocephalus. The CSF pulsatile-flow pattern was assumed to change according to the degree of the CSF circulatory disorder, its compensatory process, and the plasticity of the brain. The investigation of the CSF pulsatile flow gives important information for the evaluation of various hydrocephalic conditions. (author)

Basal-bolus insulin therapy reduces maternal triglycerides in gestational diabetes without modifying cholesteryl ester transfer protein activity.

Science.gov (United States)

Olmos, Pablo R; Borzone, Gisella R

2017-09-01

Macrosomia in the offspring of overweight/obese mothers with glucose-controlled gestational diabetes mellitus (GDM) is due to excessive rise of maternal triglycerides (TG). We aimed to ascertain whether basal-bolus insulin therapy (BBIT), or other components of the treatment, could reduce TG in GDM. We studied the records of 131 singleton pregnancies with GDM, using stepwise multiple linear regression, Mann-Whitney, χ 2 , and Jonckheere-Terpstra tests. As maternal TG increased steadily during normal pregnancy, these were transformed as z-scores. The atherogenic index of plasma (AIP) was calculated as a measure of cholesteryl ester transfer protein activity. Multiple regression showed that only BBIT (but neither limitation of weight gain nor metformin) reduced maternal TG z-scores (P = 0.011). When the 131 pregnancies were split into two groups - without BBIT (n = 58; HbA1c = 5.3 ± 0.3%) and with BBIT (n = 73; HbA1c = 5.4 ± 0.6; P = 0.2005) - we observed that BBIT (n = 73) reduced maternal TG z-scores in a dose-related fashion (Jonckheere-Terpstra P = 0.03817). The atherogenic index of plasma remained within normal range in both groups. BBIT (but not weight gain control nor metformin) reduced maternal TG in mothers with glucose-controlled GDM. This beneficial effect of BBIT was not related to changes in the cholesteryl ester transfer protein activity. © 2017 Japan Society of Obstetrics and Gynecology.

Single bolus dose of epidural magnesium prolongs the duration of analgesia in cardiac patients undergoing vascular surgeries

Directory of Open Access Journals (Sweden)

Amarja Sachin Nagre

2017-01-01

Full Text Available Background and Aims: Magnesium, a physiological antagonist of calcium and N-methyl-d-aspartate, has a role in the prevention of pain in patients undergoing surgery for peripheral vascular diseases with cardiac comorbidities such as ischaemic heart disease and coronary artery disease. The objective of our study was assessment of effects of epidural magnesium in cardiac patients undergoing vascular surgery. Methods: Sixty patients of either sex American Society of Anesthesiologists physical status III undergoing surgeries for peripheral vascular diseases were enrolled. The control group had 30 patients who received levobupivacaine 0.25% 10 ml with fentanyl 50 μg while 30 patients in study group received levobupivacaine 0.25% 10 ml with fentanyl 50 μg and magnesium 100 mg. The primary outcome was duration of analgesia. Sedation score, pain assessment using visual analogue scale (VAS, systolic blood pressure (SBP and diastolic blood pressure (DBP, heart rate (HR, respiratory rate (RR and fentanyl consumption were also recorded. Statistical analyses were performed using Minitab 15 statistical software. Results: Both groups were similar demographically and with respect to baseline HR, SBP, DBP and RR. In the study group, compared to the control group, duration of analgesia was 4.17 ± 1.07 h versus 1.55 ± 0.47 h (P < 0.01, sedation score were\\ better (P = 0.003 and the VAS scores was lower (P < 0.01. sConclusion: Epidural magnesium, added to levobupivacaine and fentanyl as a single bolus dose effectively prolongs the duration of analgesia in high-risk cardiac patients undergoing peripheral vascular surgery.

Comparison of first pass bolus AIFs extracted from sequential {sup 18}F-FDG PET and DSC-MRI of mice

Energy Technology Data Exchange (ETDEWEB)

Evans, Eleanor, E-mail: ee244@cam.ac.uk [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom); Sawiak, Stephen J. [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom); Behavioural and Clinical Neuroscience Institute, Department of Experimental Psychology, University of Cambridge, Cambridge, CB2 3EB (United Kingdom); Ward, Alexander O.; Buonincontri, Guido; Hawkes, Robert C.; Adrian Carpenter, T. [Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, School of Clinical Medicine, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ (United Kingdom)

2014-01-11

Accurate kinetic modelling of in vivo physiological function using positron emission tomography (PET) requires determination of the tracer time–activity curve in plasma, known as the arterial input function (AIF). The AIF is usually determined by invasive blood sampling methods, which are prohibitive in murine studies due to low total blood volumes. Extracting AIFs from PET images is also challenging due to large partial volume effects (PVE). We hypothesise that in combined PET with magnetic resonance imaging (PET/MR), a co-injected bolus of MR contrast agent and PET ligand can be tracked using fast MR acquisitions. This protocol would allow extraction of a MR AIF from MR contrast agent concentration–time curves, at higher spatial and temporal resolution than an image-derived PET AIF. A conversion factor could then be applied to the MR AIF for use in PET kinetic analysis. This work has compared AIFs obtained from sequential DSC-MRI and PET with separate injections of gadolinium contrast agent and {sup 18}F-FDG respectively to ascertain the technique′s validity. An automated voxel selection algorithm was employed to improve MR AIF reproducibility. We found that MR and PET AIFs displayed similar character in the first pass, confirmed by gamma variate fits (p<0.02). MR AIFs displayed reduced PVE compared to PET AIFs, indicating their potential use in PET/MR studies.

Mapping water exchange rates in rat tumor xenografts using the late-stage uptake following bolus injections of contrast agent.

Science.gov (United States)

Bailey, Colleen; Moosvi, Firas; Stanisz, Greg J

2014-05-01

To map the intra-to-extracellular water exchange rate constant in rat xenografts using a two-compartment model of relaxation with water exchange and a range of contrast agent concentrations and compare with histology. MDA-MB-231 cells were xenografted into six nude rats. Three bolus injections of gadodiamide were administered. When uptake in the tumor demonstrated a steady-state, T1 data were acquired by spoiled gradient recalled acquisitions at four flip angles. A global fit of data to a two-compartment model incorporating exchange was performed, assuming a distribution volume of 20% of the rat. Voxels that did not reach steady-state and were excluded from parametric maps tended to be in large necrotic areas. TUNEL-negative (nonapoptotic) regions tended to have well-defined error bounds, with an average intra-to-extracellular exchange rate constant of 0.6 s(-1) . Apoptotic regions had higher exchange, but poorly determined upper bounds, with goodness of fit similar to that for a model assuming infinitely fast exchange. A lower bound of >3 s(-1) was used to establish voxels where the exchange rate constant was fast despite a large upper bound. Water exchange rates were higher in apoptotic regions, but examination of statistical errors was an important step in the mapping process. Copyright © 2013 Wiley Periodicals, Inc.

Comparative study of intravenous urographic bolus (I.U.B.) and intravenous urographic infusion (I.U.I.) in dogs

International Nuclear Information System (INIS)

Thibaut L, Julio; Ditzel, G.; Vargas, L; Born, R; Deppe G, Rodolfo

1996-01-01

Two urographic methods were compared: the intravenous urographic bolus (i.u.b.) and the intravenous urographic infusion (i.u.i.). In both methods, two groups of seven healthy adult dogs of both sexes, weighing7.0 to 16.5 kg were used and were anaesthesized with 2% thiopentone sodium in doses of 20 mg/kg via cephalica. In the i.u.b., meglumine diatrizoate (Hypaque-M, 60%) was injected via saphena with a concentration of 282 mg of iodine per mi in doses of 564 mg of iodine per kg. In the i.u.i., meglumine diatrizoate was injected via saphena by drip infusion with a concentration of 200 mg of iodine per mi in doses of 500 mg of iodine per kg. Three series of two X-rays each were taken in ventrodorsal projection 1, 4 and 8 min and left lateral recumbency 30 sec after administering the contrast medium. The X-ray plates obtained were analyzed and compared intra and inter group considering the advance speed of the contrast medium, the radiographic density and outline, and kidney size. The advance speed of the contrast medium was higher in the i.u.i., reaching the kidney, ureter and bladder 1 min after administration in both projections; in ventrodorsal projections in the i.u.b. only the kidneys were reached while in the left lateral recumbency, the kidney and ureters were reached [es

Evaluation of two-dimensional bolus effect of immobilization/support devices on skin doses: A radiochromic EBT film dosimetry study in phantom

International Nuclear Information System (INIS)

Chiu-Tsao, Sou-Tung; Chan, Maria F.

2010-01-01

Purpose: In this study, the authors have quantified the two-dimensional (2D) perspective of skin dose increase using EBT film dosimetry in phantom in the presence of patient immobilization devices during conventional and IMRT treatments. Methods: For 6 MV conventional photon field, the authors evaluated and quantified the 2D bolus effect on skin doses for six different common patient immobilization/support devices, including carbon fiber grid with Mylar sheet, Orfit carbon fiber base plate, balsa wood board, Styrofoam, perforated AquaPlast sheet, and alpha-cradle. For 6 and 15 MV IMRT fields, a stack of two film layers positioned above a solid phantom was exposed at the air interface or in the presence of a patient alpha-cradle. All the films were scanned and the pixel values were converted to doses based on an established calibration curve. The authors determined the 2D skin dose distributions, isodose curves, and cross-sectional profiles at the surface layers with or without the immobilization/support device. The authors also generated and compared the dose area histograms (DAHs) and dose area products from the 2D skin dose distributions. Results: In contrast with 20% relative dose [(RD) dose relative to d max on central axis] at 0.0153 cm in the film layer for 6 MV 10x10 cm 2 open field, the average RDs at the same depth in the film layer were 71%, 69%, 55%, and 57% for Orfit, balsa wood, Styrofoam, and alpha-cradle, respectively. At the same depth, the RDs were 54% under a strut and 26% between neighboring struts of a carbon fiber grid with Mylar sheet, and between 34% and 56% for stretched perforated AquaPlast sheet. In the presence of the alpha-cradle for the 6 MV (15 MV) IMRT fields, the hot spot doses at the effective measurement depths of 0.0153 and 0.0459 cm were 140% and 150% (83% and 89%), respectively, of the isocenter dose. The enhancement factor was defined as the ratio of a given DAH parameter (minimum dose received in a given area) with and without

MO-B-BRD-03: Principles, Pitfalls and Techniques of 3D Printing for Bolus and Compensators

International Nuclear Information System (INIS)

Baker, J.

2015-01-01

This session is designed so that the learning objectives are practical. The intent is that the attendee may take home an understanding of not just the technology, but also the logistical steps necessary to execute these 3D printing techniques in the clinic. Four practical 3D printing topics will be discussed: (i) Creating bolus and compensators for photon machines; (ii) tools for proton therapy; (iii) clinical applications in imaging; (iv) custom phantom design for clinic and research use. The use of 3D printers within the radiation oncology setting is proving to be a useful tool for creating patient specific bolus and compensators with the added benefit of cost savings. Creating the proper protocol is essential to ensuring that the desired effect is achieved and modeled in the treatment planning system. The critical choice of printer material (since it determines the interaction with the radiation) will be discussed. Selection of 3D printer type, design methods, verification of dose calculation, and the printing process will be detailed to give the basis for establishing your own protocol for electron and photon fields. A practical discussion of likely obstacles that may be encountered will be included. The diversity of systems and techniques in proton facilities leads to different facilities having very different requirements for beam modifying hardware and quality assurance devices. Many departments find the need to design and fabricate facility-specific equipment, making 3D printing an attractive technology. 3D printer applications in proton therapy will be discussed, including beam filters and compensators, and the design of proton therapy specific quality assurance tools. Quality control specific to 3D printing in proton therapy will be addressed. Advantages and disadvantages of different printing technology for these applications will also be discussed. 3D printing applications using high-resolution radiology-based imaging data will be presented. This data

MO-B-BRD-03: Principles, Pitfalls and Techniques of 3D Printing for Bolus and Compensators

Energy Technology Data Exchange (ETDEWEB)

Baker, J. [Stony Brook University Medical Center (United States)

2015-06-15

This session is designed so that the learning objectives are practical. The intent is that the attendee may take home an understanding of not just the technology, but also the logistical steps necessary to execute these 3D printing techniques in the clinic. Four practical 3D printing topics will be discussed: (i) Creating bolus and compensators for photon machines; (ii) tools for proton therapy; (iii) clinical applications in imaging; (iv) custom phantom design for clinic and research use. The use of 3D printers within the radiation oncology setting is proving to be a useful tool for creating patient specific bolus and compensators with the added benefit of cost savings. Creating the proper protocol is essential to ensuring that the desired effect is achieved and modeled in the treatment planning system. The critical choice of printer material (since it determines the interaction with the radiation) will be discussed. Selection of 3D printer type, design methods, verification of dose calculation, and the printing process will be detailed to give the basis for establishing your own protocol for electron and photon fields. A practical discussion of likely obstacles that may be encountered will be included. The diversity of systems and techniques in proton facilities leads to different facilities having very different requirements for beam modifying hardware and quality assurance devices. Many departments find the need to design and fabricate facility-specific equipment, making 3D printing an attractive technology. 3D printer applications in proton therapy will be discussed, including beam filters and compensators, and the design of proton therapy specific quality assurance tools. Quality control specific to 3D printing in proton therapy will be addressed. Advantages and disadvantages of different printing technology for these applications will also be discussed. 3D printing applications using high-resolution radiology-based imaging data will be presented. This data

Student Assessment in the Ubiquitously Connected World

OpenAIRE

Adams, A. A.

2017-01-01

Student cheating on university assessments from entrance exams to finals and from contract cheating on coursework to requesting exam answers using a mobile phone during the exam, has received more and more attention of late. As connection to the Internet becomes ubiquitous and computing and communications technology more embedded in our environment, it is argued that a re-focussing on providing educational opportunities is needed in higher education, rather than chasing the ever-retreating p...

The utilization of SA-gal in pre-targeting RIT of colon carcinoma xenograft models

International Nuclear Information System (INIS)

Wu Hubing; Huang Zuhan; Peng Wuhe; Gao Xiao

2001-01-01

To investigate the improved clearance effect of avidin (Av) and streptavidin-gal (SA - gal) for blood radiolabeled biotinylated antibody in pre-targeting radio-immuno therapy (RIT) of colon carcinoma xenograft models. Biotinylated antibody radiolabeled with 131 I was injected into the nude mice bearing the colon carcinoma via the tail vein. 24 h later, in 2 test groups, SA-gal or Av at a 10 - fold molar excess of antibody was intraperitoneally injected into the animals whereas no any chase agents were given to the control animals. Animals were killed for biodistribution study at 30h after 131 I-labelled biotinylated antibody administration. Results showed that Av and SA-gal took the effect of chase very fast. At 6h after injection, the blood level of radioactivity decreased very fast. The tumor/blood ratios of control group, Av chase group, SA-gal chase group were 0.42, 2.09, 5.23 respectively, P < 0.05 and P < 0.01 for the latter two groups as compared other control groups. Compared with Av, SA-gal showed better chase effect, its T/B ratios was 5.23, significantly higher than 2.09 of Av (P < 0.01). In the tissue biodistributions, relatively high non-specific radioactivity uptakes in non-liver organs were seen in Av chase group. Utilized in pre-targeting RIT, both Av and SA-gal could make the blood level of radioactivity decrease quickly and considerably improves tumor T/NT ratios. The chase effect of SA-gal was superior to that of avidin

MDMA ‘ecstasy’ increases cerebral cortical perfusion determined by bolus-tracking arterial spin labelling (btASL) MRI

Science.gov (United States)

Rouine, J; Gobbo, O L; Campbell, M; Gigliucci, V; Ogden, I; McHugh Smith, K; Duffy, P; Behan, B; Byrne, D; Kelly, M E; Blau, C W; Kerskens, C M; Harkin, A

2013-01-01

Background and Purpose The purpose of this study was to assess cerebral perfusion changes following systemic administration of the recreational drug 3,4-methylendioxymethamphetamine (MDMA ‘ecstasy’) to rats. Experimental Approach Cerebral perfusion was quantified using bolus-tracking arterial spin labelling (btASL) MRI. Rats received MDMA (20 mg·kg−1; i.p.) and were assessed 1, 3 or 24 h later. Rats received MDMA (5 or 20 mg·kg−1; i.p.) and were assessed 3 h later. In addition, rats received MDMA (5 or 10 mg·kg−1; i.p.) or saline four times daily over 2 consecutive days and were assessed 8 weeks later. Perfusion-weighted images were generated in a 7 tesla (7T) MRI scanner and experimental data was fitted to a quantitative model of cerebral perfusion to generate mean transit time (MTT), capillary transit time (CTT) and signal amplitude. Key Results MDMA reduces MTT and CTT and increases amplitude in somatosensory and motor cortex 1 and 3 h following administration, indicative of an increase in perfusion. Prior exposure to MDMA provoked a long-term reduction in cortical 5-HT concentration, but did not produce a sustained effect on cerebral cortical perfusion. The response to acute MDMA challenge (20 mg·kg−1; i.p.) was attenuated in these animals indicating adaptation in response to prior MDMA exposure. Conclusions and Implications MDMA provokes changes in cortical perfusion, which are quantifiable by btASL MRI, a neuroimaging tool with translational potential. Future studies are directed towards elucidation of the mechanisms involved and correlating changes in cerebrovascular function with potential behavioural deficits associated with drug use. PMID:23517012

Effects of switching from prandial premixed insulin therapy to basal plus two times bolus insulin therapy on glycemic control and quality of life in patients with type 2 diabetes mellitus

Directory of Open Access Journals (Sweden)

Ito H

2014-04-01

Full Text Available Hiroyuki Ito, Mariko Abe, Shinichi Antoku, Takashi Omoto, Masahiro Shinozaki, Shinya Nishio, Mizuo Mifune, Michiko ToganeDepartment of Diabetes, Metabolism and Kidney Disease, Edogawa Hospital, Tokyo, JapanBackground: The effects of switching from prandial premixed insulin therapy (PPT injected three times a day to basal plus two times bolus insulin therapy (B2B on glycemic control and quality of life were investigated in patients with type 2 diabetes mellitus.Methods: The clinical course was prospectively observed during the first 16 weeks after switching to B2B (insulin glargine plus insulin glulisine before breakfast and dinner in 27 subjects previously treated with PPT using 50/50 premixed insulin. The Diabetes Treatment Satisfaction Questionnaire (DTSQ was administered at the start and end of the study.Results: The glycated hemoglobin (HbA1c level (8.3%±1.8% to 8.2%±1.1% and the DTSQ score did not change between the start and end of the study. An improvement in HbA1c level was found in nine (33% subjects. The change in HbA1c showed a significant negative correlation with baseline HbA1c, and was significantly better in patients with a baseline HbA1c >8.0% than in those with an HbA1c ≤8.0% (−0.9±2.0 versus 0.3±0.6, respectively, P=0.02. The change in DTSQ score representing treatment satisfaction was significantly greater in patients whose HbA1c level was improved than in those in whom it was not (2.7±3.6 versus −0.8±3.5, P=0.04.Conclusion: B2B was noninferior to PPT with regard to HbA1c levels in patients with type 2 diabetes mellitus. B2B should be considered particularly for subjects whose glycemic control is poor despite PPT.Keywords: type 2 diabetes mellitus, insulin therapy, basal plus two times bolus insulin therapy, prandial premixed insulin therapy, Diabetes Treatment Satisfaction Questionnaire

78 FR 8157 - National Institute of General Medical Sciences; Notice of Closed Meeting

Science.gov (United States)

2013-02-05

... Marriott Chevy Chase, 5520 Wisconsin Avenue, Chevy Chase, MD 20815. Contact Person: Mona R. Trempe, Ph.D... Chemistry Research; 93.862,Genetics and Developmental Biology Research; 93.88, Minority Access to Research...

Computed tomography in pancreas cancer

International Nuclear Information System (INIS)

Fujita, Nobuyuki; Matsuoka, Yoshisuke; Choji, Kiyoshi; Mizuo, Hideyo; Shinohara, Masahiro; Morita, Yutaka; Irie, Goro

1985-01-01

We reviewed CT pictures of 31 cases of pancreas cancer to examine detectability of vascular involvement. To demonstrate vascular abnormalities distinctly, we performed bolus injection of contrast medium, followed by drip infusion. The vessels included in this study were portal vein, superior mesenteric vein, and splenic vein. We concluded as below, 1) CT is valuable tool for detection of the vascular abnormality, and can demonstrate vascular involvement distinctly in a case of pancreas cancer. 2) The detectability of the vascular abnormality was correlated well with the result of angiography. 3) The differentiation between stenosis and obstruction was thought to be impossible only with the local vascular changes. But with an information of the collateral pathway, the diagnosis of obstruction was possible. CT can demonstrate these collaterals in 7 of 8 cases. (author)

Thermal characteristics of thermobrachytherapy surface applicators for treating chest wall recurrence

International Nuclear Information System (INIS)

Arunachalam, K; Maccarini, P F; Craciunescu, O I; Stauffer, P R; Schlorff, J L

2010-01-01

. Lower bolus temperature may be chosen to reduce the thermal enhancement ratio (TER) in the most sensitive skin where maximum radiation dose is delivered and to extend the thermal enhancement of radiation dose deeper. This computational study indicates that well-localized elevation of tumor target temperature to 40-44 deg. C can be accomplished by large surface-conforming TBSAs using appropriate selection of coupling bolus temperature.

New alternatives in veterinary anthelminthic therapy

Directory of Open Access Journals (Sweden)

Romeo T. Cristina

2007-07-01

Full Text Available Present paper proposes the presentation of antiparasitic boluses, veterinary use specific conditionings with importance in gastro intestinal helminth population control, as a modern alternative to the classic antihelmintic therapy. The active substances are released consecutive to: diffusion, osmotic procesess, to progressive erosion, or through electronic programmed devices. Anthelmintic boluses are classified upon the releasing system in: a anthelmintic sustained release systems: for albendazole (Proftril bolus, morantel tartrate (Paratect flex and bolus ivermectines (Enzec and Alzet, Ivomec SR Bolus, levamisole (Chronominthic bolus, oxfendazol (Synanthic multidose bolus fenbendazole (Panacur Bolus.b anthelmintic programmed periodic release systems: Intra Ruminal Pulse Release Electronic Device (I.R.P.R.E.D and Repidose (Autoworm, Oxfendazole Pulsed Release Bolus.

Energy cost and return for hunting in African wild dogs and cheetahs

OpenAIRE

Hubel, Tatjana Y.; Myatt, Julia P.; Jordan, Neil R.; Dewhirst, Oliver P.; McNutt, J. Weldon; Wilson, Alan M.

2016-01-01

African wild dogs (Lycaon pictus) are reported to hunt with energetically costly long chase distances. We used high-resolution GPS and inertial technology to record 1,119 high-speed chases of all members of a pack of six adult African wild dogs in northern Botswana. Dogs performed multiple short, high-speed, mostly unsuccessful chases to capture prey, while cheetahs (Acinonyx jubatus) undertook even shorter, higher-speed hunts. We used an energy balance model to show that the energy return fr...

Clinical applications of 3-dimensional printing in radiation therapy

International Nuclear Information System (INIS)

Zhao, Yizhou; Moran, Kathryn; Yewondwossen, Mammo; Allan, James; Clarke, Scott; Rajaraman, Murali; Wilke, Derek; Joseph, Paul; Robar, James L.

2017-01-01

Three-dimensional (3D) printing is suitable for the fabrication of complex radiotherapy bolus. Although investigated from dosimetric and feasibility standpoints, there are few reports to date of its use for actual patient treatment. This study illustrates the versatile applications of 3D printing in clinical radiation oncology through a selection of patient cases, namely, to create bolus for photon and modulated electron radiotherapy (MERT), as well as applicators for surface high-dose rate (HDR) brachytherapy. Photon boluses were 3D-printed to treat a recurrent squamous cell carcinoma (SCC) of the nasal septum and a basal cell carcinoma (BCC) of the posterior pinna. For a patient with a mycosis fungoides involving the upper face, a 3D-printed MERT bolus was used. To treat an SCC of the nose, a 3D-printed applicator for surface brachytherapy was made. The structures' fit to the anatomy and the radiotherapy treatment plans were assessed. Based on the treatment planning computed tomography (CT), the size of the largest air gap at the interface of the 3D-printed structure was 3 mm for the SCC of the nasal septum, 3 mm for the BCC of the pinna, 2 mm for the mycosis fungoides of the face, and 2 mm for the SCC of the nose. Acceptable treatment plans were obtained for the SCC of the nasal septum (95% isodose to 99.8% of planning target volume [PTV]), the BCC of the pinna (95% isodose to 97.7% of PTV), and the mycosis fungoides of the face (90% isodose to 92.5% of PTV). For the latter, compared with a plan with a uniform thickness bolus, the one featuring the MERT bolus achieved relative sparing of all the organs at risk (OARs) distal to the target volume, while maintaining similar target volume coverage. The surface brachytherapy plan for the SCC of the nose had adequate coverage (95% isodose to 95.6% of clinical target volume [CTV]), but a relatively high dose to the left eye, owing to its proximity to the tumor. 3D printing can be implemented effectively in

Clinical applications of 3-dimensional printing in radiation therapy

Energy Technology Data Exchange (ETDEWEB)

Zhao, Yizhou, E-mail: yizhou.zhao@dal.ca [Department of Radiation Oncology, Dalhousie University, Queen Elizabeth II Health Sciences Centre, 5820 University Avenue, Halifax, Nova Scotia B3H 2Y9 (Canada); Moran, Kathryn [Department of Radiation Oncology, Dalhousie University, Queen Elizabeth II Health Sciences Centre, 5820 University Avenue, Halifax, Nova Scotia B3H 2Y9 (Canada); Yewondwossen, Mammo; Allan, James; Clarke, Scott [Department of Medical Physics, Dalhousie University, Queen Elizabeth II Health Sciences Centre, 5820 University Avenue, Halifax, Nova Scotia B3H 2Y9 (Canada); Rajaraman, Murali; Wilke, Derek; Joseph, Paul [Department of Radiation Oncology, Dalhousie University, Queen Elizabeth II Health Sciences Centre, 5820 University Avenue, Halifax, Nova Scotia B3H 2Y9 (Canada); Robar, James L. [Department of Medical Physics, Dalhousie University, Queen Elizabeth II Health Sciences Centre, 5820 University Avenue, Halifax, Nova Scotia B3H 2Y9 (Canada)

2017-07-01

Three-dimensional (3D) printing is suitable for the fabrication of complex radiotherapy bolus. Although investigated from dosimetric and feasibility standpoints, there are few reports to date of its use for actual patient treatment. This study illustrates the versatile applications of 3D printing in clinical radiation oncology through a selection of patient cases, namely, to create bolus for photon and modulated electron radiotherapy (MERT), as well as applicators for surface high-dose rate (HDR) brachytherapy. Photon boluses were 3D-printed to treat a recurrent squamous cell carcinoma (SCC) of the nasal septum and a basal cell carcinoma (BCC) of the posterior pinna. For a patient with a mycosis fungoides involving the upper face, a 3D-printed MERT bolus was used. To treat an SCC of the nose, a 3D-printed applicator for surface brachytherapy was made. The structures' fit to the anatomy and the radiotherapy treatment plans were assessed. Based on the treatment planning computed tomography (CT), the size of the largest air gap at the interface of the 3D-printed structure was 3 mm for the SCC of the nasal septum, 3 mm for the BCC of the pinna, 2 mm for the mycosis fungoides of the face, and 2 mm for the SCC of the nose. Acceptable treatment plans were obtained for the SCC of the nasal septum (95% isodose to 99.8% of planning target volume [PTV]), the BCC of the pinna (95% isodose to 97.7% of PTV), and the mycosis fungoides of the face (90% isodose to 92.5% of PTV). For the latter, compared with a plan with a uniform thickness bolus, the one featuring the MERT bolus achieved relative sparing of all the organs at risk (OARs) distal to the target volume, while maintaining similar target volume coverage. The surface brachytherapy plan for the SCC of the nose had adequate coverage (95% isodose to 95.6% of clinical target volume [CTV]), but a relatively high dose to the left eye, owing to its proximity to the tumor. 3D printing can be implemented effectively in

Simulation technique on combustion of solid propellant; Kotai suishin`yaku nensho no simyureshon gijutsu

Energy Technology Data Exchange (ETDEWEB)

Iida, Akihide.; Bazaki, Hakobu.; Douke, Kiyotaka. [Asahi Chemical Industry Corp., Tokyo (Japan). Oita Plant

1999-04-30

The burning area of propellant grain is one of the most important parameter in conducting of design on solid rocket performance. However, it has been difficult to calculate the burning area of propellant grain with precise and speed by geometrical way since most of propellant configuration have been adopted as complicated. In the present study, the simulation system was developed and produced, which was adapted `particle chasing method` to and made ot compute the burning area transition. Moreover, the reliability on computation by the system was check up on. It was found that the discrepancy of calculation between by the geometrical way and by the system was less than 1%. (author)

The BR eigenvalue algorithm

Energy Technology Data Exchange (ETDEWEB)

Geist, G.A. [Oak Ridge National Lab., TN (United States). Computer Science and Mathematics Div.; Howell, G.W. [Florida Inst. of Tech., Melbourne, FL (United States). Dept. of Applied Mathematics; Watkins, D.S. [Washington State Univ., Pullman, WA (United States). Dept. of Pure and Applied Mathematics

1997-11-01

The BR algorithm, a new method for calculating the eigenvalues of an upper Hessenberg matrix, is introduced. It is a bulge-chasing algorithm like the QR algorithm, but, unlike the QR algorithm, it is well adapted to computing the eigenvalues of the narrowband, nearly tridiagonal matrices generated by the look-ahead Lanczos process. This paper describes the BR algorithm and gives numerical evidence that it works well in conjunction with the Lanczos process. On the biggest problems run so far, the BR algorithm beats the QR algorithm by a factor of 30--60 in computing time and a factor of over 100 in matrix storage space.

SU-F-T-387: A Novel Optimization Technique for Field in Field (FIF) Chestwall Radiation Therapy Using a Single Plan to Improve Delivery Safety and Treatment Planning Efficiency

Energy Technology Data Exchange (ETDEWEB)

Tabibian, A; Kim, A; Rose, J; Alvelo, M; Perel, C; Laiken, K; Sheth, N [Bayonne Medical Center, Bayonne, New Jersey (United States)

2016-06-15

Purpose: A novel optimization technique was developed for field-in-field (FIF) chestwall radiotherapy using bolus every other day. The dosimetry was compared to currently used optimization. Methods: The prior five patients treated at our clinic to the chestwall and supraclavicular nodes with a mono-isocentric four-field arrangement were selected for this study. The prescription was 5040 cGy in 28 fractions, 5 mm bolus every other day on the tangent fields, 6 and/or 10 MV x-rays, and multileaf collimation.Novelly, tangents FIF segments were forward planned optimized based on the composite bolus and non-bolus dose distribution simultaneously. The prescription was spilt into 14 fractions for both bolus and non-bolus tangents. The same segments and monitor units were used for the bolus and non-bolus treatment. The plan was optimized until the desired coverage was achieved, minimized 105% hotspots, and a maximum dose of less than 108%. Each tangential field had less than 5 segments.Comparison plans were generated using FIF optimization with the same dosimetric goals, but using only the non-bolus calculation for FIF optimization. The non-bolus fields were then copied and bolus was applied. The same segments and monitor units were used for the bolus and non-bolus segments. Results: The prescription coverage of the chestwall, as defined by RTOG guidelines, was on average 51.8% for the plans that optimized bolus and non-bolus treatments simultaneous (SB) and 43.8% for the plans optimized to the non-bolus treatments (NB). Chestwall coverage of 90% prescription averaged to 80.4% for SB and 79.6% for NB plans. The volume receiving 105% of the prescription was 1.9% for SB and 0.8% for NB plans on average. Conclusion: Simultaneously optimizing for bolus and non-bolus treatments noticeably improves prescription coverage of the chestwall while maintaining similar hotspots and 90% prescription coverage in comparison to optimizing only to non-bolus treatments.

SU-F-T-387: A Novel Optimization Technique for Field in Field (FIF) Chestwall Radiation Therapy Using a Single Plan to Improve Delivery Safety and Treatment Planning Efficiency

International Nuclear Information System (INIS)

Tabibian, A; Kim, A; Rose, J; Alvelo, M; Perel, C; Laiken, K; Sheth, N

2016-01-01

Purpose: A novel optimization technique was developed for field-in-field (FIF) chestwall radiotherapy using bolus every other day. The dosimetry was compared to currently used optimization. Methods: The prior five patients treated at our clinic to the chestwall and supraclavicular nodes with a mono-isocentric four-field arrangement were selected for this study. The prescription was 5040 cGy in 28 fractions, 5 mm bolus every other day on the tangent fields, 6 and/or 10 MV x-rays, and multileaf collimation.Novelly, tangents FIF segments were forward planned optimized based on the composite bolus and non-bolus dose distribution simultaneously. The prescription was spilt into 14 fractions for both bolus and non-bolus tangents. The same segments and monitor units were used for the bolus and non-bolus treatment. The plan was optimized until the desired coverage was achieved, minimized 105% hotspots, and a maximum dose of less than 108%. Each tangential field had less than 5 segments.Comparison plans were generated using FIF optimization with the same dosimetric goals, but using only the non-bolus calculation for FIF optimization. The non-bolus fields were then copied and bolus was applied. The same segments and monitor units were used for the bolus and non-bolus segments. Results: The prescription coverage of the chestwall, as defined by RTOG guidelines, was on average 51.8% for the plans that optimized bolus and non-bolus treatments simultaneous (SB) and 43.8% for the plans optimized to the non-bolus treatments (NB). Chestwall coverage of 90% prescription averaged to 80.4% for SB and 79.6% for NB plans. The volume receiving 105% of the prescription was 1.9% for SB and 0.8% for NB plans on average. Conclusion: Simultaneously optimizing for bolus and non-bolus treatments noticeably improves prescription coverage of the chestwall while maintaining similar hotspots and 90% prescription coverage in comparison to optimizing only to non-bolus treatments.

Chasing the dream : turnaround expert enlisted to commercialize stalled pumpjack technology

Energy Technology Data Exchange (ETDEWEB)

Smith, M.

2010-10-15

This article described the efforts being made to commercialize a new pumpjack. The Intellimax uses on-board computer and communications systems to monitor bottomhole conditions and self-adjust to new circumstances, and it can be monitored in real-time over the Internet. The product promises to increase production and cut costs but has faced difficulties getting into the market. The machine is price-competitive with a conventional pumpjack, safer with no exposed moving parts, and more environmentally responsible since it does not require any oiling, greasing, or regular maintenance. It uses half the power and a quarter the steel of a conventional pumpjack. The Intellimax can automatically optimize oil production and fail-safe the well, relaying important warnings to the operator via the Internet. The Intellimax uses the simplest design for an artificial lift mechanism, a linear planar wireless motor technology that was originally developed for submarines and modified with a cylindrical stator and associated armature. An electrical current is run through a magnetic field to develop thrust. Having only one moving part without any cables, pulleys, counterweights, or hydraulics makes the machine reliable and low maintenance. The pumpjack is fully autonomous and self-diagnostic, easy to optimize, and self-adaptive to well conditions. A computer-controlled, self-adaptive air counterbalancing spring system helps conserve energy by using the linear electric motor as both a brake and a spring. The Intellimax is about 80 to 90 percent efficient, whereas conventional pumpjacks are about 35 percent efficient. 1 ref., 3 figs.

Effects of a long-acting trace mineral rumen bolus supplement on growth performance, metabolic profiles, and trace mineral status of growing camels.

Science.gov (United States)

Alhidary, Ibrahim A; Abdelrahman, Mutassim M; Harron, Raafat M

2016-04-01

A study was conducted to evaluate the effects of a long-acting trace mineral rumen bolus (TMB) supplement on the productive performance, metabolic profiles, and trace mineral status of growing camels under natural grazing conditions. Fifteen 6-month-old growing male camels (average bodyweight 139.51 ± 26.49 kg) were used in a 150-day trial. Animals were individually housed in a shaded pen and randomly assigned to receive zero (control group, CON), one (TMB1), or two (TMB2) long-acting TMBs. Feed intake was measured weekly, and camels were weighed monthly. Blood samples were collected from all camels on days 1, 30, 60, 90, 120, and 150 to obtain metabolic profiles. Zinc, selenium, copper, cobalt, and manganese concentrations were determined in the diet, serum, and liver. In comparison with controls, giving camels one TMB increased the average daily gain (14.38%; P camels in the TMB2 group. These data indicate that TMB supplementation has positive effects on the growth performance and trace mineral profiles of camels. Different levels, sources, and synergistic combinations of trace minerals can be used in further studies to elucidate their abilities to increase productive variables as well as their availability and cost to the camel industry.

Multi-slice computed tomography urography after diuretic injection in children with urinary tract dilatation

Energy Technology Data Exchange (ETDEWEB)

Kosucu, P.; Ahmetoglu, A.; Imamoglu, M.; Cay, A.; Ozdemir, O.; Dinc, H.; Kosucu, M.; Sari, A.; Saruhan, H.; Gumele, H.R. [Farabi Hospital, Trabzon (Turkey). Dept. of Radiology

2004-02-01

To evaluate the potential use of multi-slice computed tomography urography (MSCTU) after diuretic injection in children with urinary tract dilatation. MSCTU was performed in 19 patients (11 boys, 8 girls, mean age 5.4 years) with suspicion of urinary tract obstruction and dilatation. Furosemide, 1 mg/kg, was injected 3 min before contrast material administration and followed by a bolus of 30 ml of physiologic saline solution immediately after application of contrast material. Excretory-phase images were obtained through the abdomen and pelvis beginning 10 min after initiation of the injection of contrast material. Maximum intensity projection (MIP) and volume rendering (VR) images were post-processed to obtain urographic views. MSCTU revealed pathology in 16 of 19 patients, while 3 patients had normal findings. Ureteropelvic obstruction was found in 4 patients, obstructive megaureter in 8. Both ureteropelvic obstruction and obstructive megaureter were disclosed in 1 patient, partial ureteral duplication in 1 patient, and both complete ureteral duplication and ureterocele in 2 patients. In all patients, MIP and VR images could satisfactorily show the pathologies of the urinary tract. The estimated effective average doses of MSCTU were higher than IVU. Preliminary results of furosemide-enhanced MSCTU demonstrated consistently dilated urinary tracts, obstruction levels, and underlying pathologies better than US and IVU.

Optimal insulin pump dosing and postprandial glycemia following a pizza meal using the continuous glucose monitoring system.

Science.gov (United States)

Jones, Susan M; Quarry, Jill L; Caldwell-McMillan, Molly; Mauger, David T; Gabbay, Robert A

2005-04-01

We attempted to identify an optimal insulin pump meal bolus by comparing postprandial sensor glucose values following three methods of insulin pump meal bolusing for a consistent pizza meal. Twenty-four patients with type 1 diabetes participated in a study to compare postprandial glucose values following three meal bolus regimens for a consistent evening pizza meal. Each participant utilized the following insulin lispro regimens on consecutive evenings, and glucose values were tracked by the Continuous Glucose Monitoring System (CGMS, Medtronic MiniMed, Northridge, CA): (a) single-wave bolus (100% of insulin given immediately); (b) 4-h dual-wave bolus (50% of insulin given immediately and 50% given over a 4-h period); and (c) 8-h dual-wave bolus (50% of insulin given immediately and 50% given over a 8-h period). Total insulin bolus amount was kept constant for each pizza meal. Divergence in blood glucose among the regimens was greatest at 8-12 h. The 8-h dual-wave bolus provided the best glycemic control and lowest mean glucose values (singlewave bolus, 133 mg/dL; 4-h dual-wave bolus, 145 mg/dL; 8-h dual-wave bolus, 104 mg/dL), leading to a difference in mean glucose of 29 mg/dL for the single-wave bolus versus the 8-h dual-wave bolus and 42 mg/dL for the 4-h dual-wave bolus versus the 8-h dual-wave bolus. The lower mean glucose in the 8-h dual-wave bolus was not associated with any increased incidence of hypoglycemia. Use of a dual-wave bolus extended over an 8-h period following a pizza meal provided significantly less postprandial hyperglycemia in the late postprandial period (8-12 h) with no increased risk of hypoglycemia.

Assessment of hypertrophic cardiomyopathy by ECG gated cardiac computed tomography

International Nuclear Information System (INIS)

Takeuchi, Kazuhide; Tanaka, Chujiro; Oku, Hisao

1981-01-01

The applicability of ECG gated cardiac computed tomography (CT) in 12 patients with hypertrophic cardiomyopathy was examined. Six of the 12 patients had hypertrophic obstructive cardiomyopathy, including one patient with mid-ventricular obstruction. Three of the 12 patients had hypertrophic non-obstructive cardiomyopathy, and three had apical hypertrophic cardiomyopathy. The diagnosis of hypertrophic cardiomyopathy was confirmed by the angiocardiogram in all patients. Cardiac CT was performed after intravenous administration of contrast media usually given as a bolus injection. The gantry was set with positive 20 0 tilt angle. In all patients with hypertrophic obstructive cardiomyopathy except for mid-ventricular obstruction, the hypertrophied interventricular septum in the basal and mid portions was observed, and the left ventricular cavity was narrowed in systole. In a patient with mid-ventricular obstruction, the marked hypertrophied interventricular septum and antero-lateral papillary muscle were observed. In diastole, the left ventricular cavity was narrow and divided into two parts. The apical cavity was completely disappeared in systole. In all patients with hypertrophic non-obstructive cardiomyopathy, the diffuse hypertrophied interventricular septum was observed in diastole. In systole, the apical portion of the left ventricular cavity was markedly narrow and antero-lateral papillary muscle was hypertrophic. In all patients with apical hypertrophic cardiomyopathy, the marked apical hypertrophy of the left ventricular wall was observed in diastole. It is concluded that ECG gated cardiac CT could estimate myocardial wall motion and thickness and differentiate the types of hypertrophic cardiomyopathy each other. (author)

Dosing of Milrinone in Preterm Neonates to Prevent Postligation Cardiac Syndrome: Simulation Study Suggests Need for Bolus Infusion.

Science.gov (United States)

Hallik, Maarja; Tasa, Tõnis; Starkopf, Joel; Metsvaht, Tuuli

2017-01-01

Milrinone has been suggested as a possible first-line therapy for preterm neonates to prevent postligation cardiac syndrome (PLCS) through decreasing systemic vascular resistance and increasing cardiac contractility. The optimal dosing regimen, however, is not known. To model the dosing of milrinone in preterm infants for prevention of PLCS after surgical closure of patent ductus arteriosus (PDA). Milrinone time-concentration profiles were simulated for 1,000 subjects using the volume of distribution and clearance estimates based on one compartmental population pharmacokinetic model by Paradisis et al. [Arch Dis Child Fetal Neonatal Ed 2007;92:F204-F209]. Dose optimization was based on retrospectively collected demographic data from neonates undergoing PDA ligation in Estonian PICUs between 2012 and 2014 and existing pharmacodynamic data. The target plasma concentration was set at 150-200 ng/ml. The simulation study used demographic data from 31 neonates who underwent PDA ligation. The median postnatal age was 13 days (range: 3-29) and weight was 760 g (range: 500-2,351). With continuous infusion of milrinone 0.33 μg/kg/min, the proportion of subjects within the desired concentration range was 0% by 3 h, 36% by 6 h, and 61% by 8 h; 99% of subjects exceeded the range by 18 h. The maximum proportion of total simulated concentrations in the target range was attained with a bolus infusion of 0.73 μg/kg/min for 3 h followed by a 0.16-μg/kg/min maintenance infusion. Mathematical simulations suggest that in preterm neonates the plasma time-concentration profile of milrinone can be optimized with a slow loading dose followed by maintenance infusion. © 2016 S. Karger AG, Basel.