WorldWideScience

Sample records for correct vascular malfunction

  1. Correction of malfunctioning peritoneal dialysis catheter with guidewire and stiffener under fluoroscopic guidance

    International Nuclear Information System (INIS)

    Lee, Seung Ryong; Baek, Kyong Hee; Jung, Gyoo Sik; Huh, Jin Do; Joh, Young Duk; Rim, Hark

    1997-01-01

    To determine the efficacy of correction of a malfunctioning peritoneal dialysis catheter with guidewire and stiffener under fluoroscopic guidance. Between November 1994 and March 1997, we performed 15 manipulations in 12 patients in whom a dual-cuff, straight Tenckhoff peritoneal dialysis catheter had been implanted due to chronic renal failure. The causes of catheter malfunctioning were inadequate drainage of the dialysate(n=14) and painful dialysis(n=1). Under fluoroscopic guidance, adhesiolysis and repositioning of the malfunctioning catheter were performed with an Amplatz Super Stiff guidewire and the stiffener from a biliary drainage catheter. The results of procedures were categorized as either immediate or durable success, this latter being defined as adequate catheter function for at least one month after the procedure. Immediate success was achieved in 14 of 15 procedures (93%), and durable success in 7 of 15(47%). The mean duration of catheter function was 157 (range, 30 to 578) days. After manipulation, abdominal pain developed in eight patients and peritonitis in two, but with conservative treatment, these symptoms improved. The correction of a malfunctioning peritoneal dialysis catheter with guidewire and stiffener under fluoroscopic guidance is an effective means of restoring catheter function and may be an effective alternative to surgical reimplantation of the catheter, or hemodialysis

  2. Correction of malfunctioning peritoneal dialysis catheter with guidewire and stiffener under fluoroscopic guidance

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Ryong; Baek, Kyong Hee; Jung, Gyoo Sik; Huh, Jin Do; Joh, Young Duk; Rim, Hark [Kosin Medical College, Pusan (Korea, Republic of)

    1997-11-01

    To determine the efficacy of correction of a malfunctioning peritoneal dialysis catheter with guidewire and stiffener under fluoroscopic guidance. Between November 1994 and March 1997, we performed 15 manipulations in 12 patients in whom a dual-cuff, straight Tenckhoff peritoneal dialysis catheter had been implanted due to chronic renal failure. The causes of catheter malfunctioning were inadequate drainage of the dialysate(n=14) and painful dialysis(n=1). Under fluoroscopic guidance, adhesiolysis and repositioning of the malfunctioning catheter were performed with an Amplatz Super Stiff guidewire and the stiffener from a biliary drainage catheter. The results of procedures were categorized as either immediate or durable success, this latter being defined as adequate catheter function for at least one month after the procedure. Immediate success was achieved in 14 of 15 procedures (93%), and durable success in 7 of 15(47%). The mean duration of catheter function was 157 (range, 30 to 578) days. After manipulation, abdominal pain developed in eight patients and peritonitis in two, but with conservative treatment, these symptoms improved. The correction of a malfunctioning peritoneal dialysis catheter with guidewire and stiffener under fluoroscopic guidance is an effective means of restoring catheter function and may be an effective alternative to surgical reimplantation of the catheter, or hemodialysis.

  3. The structure of an expert system to diagnose and supply a corrective procedure for nuclear power plant malfunctions

    International Nuclear Information System (INIS)

    Hajek, B.K.; Stasenko, J.E.; Hashemi, S.; Bhatnagar, R.; Yamada, N.; Punch, W.F. III.

    1987-01-01

    Two prototype knowledge based systems have been developed at the Ohio State University. These systems were the result of collaboration between the Nuclear Engineering Program and the Laboratory for Artificial Intelligence Research (LAIR). The first system uses hierarchical classification to diagnose malfunctions of the coolant system in a General Electric Boiling Water Reactor (BWR). The second system provides a plan of action, through a process of dynamic procedure synthesis, to stabilize the plant once an abnormal transient has occurred. The objective of this paper is to discuss a structure that will integrate the two systems. The combined system will be capable of informing plant personnel about the nature of malfunctions, and of supplying to the operator the most direct corrective procedure available. Two important features of the integrated system are faulty sensor detection, based on malfunction context and unlike sensor data, and procedure synthesis based on the initial state of the plant

  4. The structure of an expert system to diagnose and supply a corrective procedure for nuclear power plant malfunctions

    International Nuclear Information System (INIS)

    Hajek, B.K.; Stasenko, J.E.; Hashemi, S.; Bhatnagar, R.; Punch, W.F. III; Yamada, N.

    1987-01-01

    During the past two years, two prototype knowledge based systems have been developed at the Ohio State University. These systems were the result of collaboration between the Nuclear Engineering Program and the Laboratory for Artificial Intelligence Research (LAIR). The first system uses hierarchical classification to diagnose malfunctions of the coolant system in a General Electric Boiling Water Reactor (BWR). The second system provides a plan of action, through a process of dynamic procedure management, to stabilize the plant once an abnormal transient has occurred. The objective of this paper is to discuss the structure that has been designed to integrate the two systems. The combined system will be capable of informing plant personnel about the nature of malfunctions, and of supplying to the operator the most direct corrective procedure available. Two important features of the integrated system are faulty sensor detection, based on malfunction context and unlike sensor data, and procedure management based on the initial state of the plant. Since the two knowledge based systems were developed separately, the integration has required a separate component currently under development, the Plant Status Monitoring System (PSMS). The task of PSMS is to monitor plant parameters in order to detect an abnormal condition developing within the plant. Based on the nature of the event, PSMS is capable of directing control to either the procedure management or diagnosis component. The integrated system plays only an advisory role, and any suggested action would be executed by the plant personnel

  5. Methods for the correction of vascular artifacts in PET O-15 water brain-mapping studies

    Science.gov (United States)

    Chen, Kewei; Reiman, E. M.; Lawson, M.; Yun, Lang-sheng; Bandy, D.; Palant, A.

    1996-12-01

    While positron emission tomographic (PET) measurements of regional cerebral blood flow (rCBF) can be used to map brain regions that are involved in normal and pathological human behaviors, measurements in the anteromedial temporal lobe can be confounded by the combined effects of radiotracer activity in neighboring arteries and partial-volume averaging. The authors now describe two simple methods to address this vascular artifact. One method utilizes the early frames of a dynamic PET study, while the other method utilizes a coregistered magnetic resonance image (MRI) to characterize the vascular region of interest (VROI). Both methods subsequently assign a common value to each pixel in the VROI for the control (baseline) scan and the activation scan. To study the vascular artifact and to demonstrate the ability of the proposed methods correcting the vascular artifact, four dynamic PET scans were performed in a single subject during the same behavioral state. For each of the four scans, a vascular scan containing vascular activity was computed as the summation of the images acquired 0-60 s after radiotracer administration, and a control scan containing minimal vascular activity was computed as the summation of the images acquired 20-80 s after radiotracer administration. t-score maps calculated from the four pairs of vascular and control scans were used to characterize regional blood flow differences related to vascular activity before and after the application of each vascular artifact correction method. Both methods eliminated the observed differences in vascular activity, as well as the vascular artifact observed in the anteromedial temporal lobes. Using PET data from a study of normal human emotion, these methods permitted the authors to identify rCBF increases in the anteromedial temporal lobe free from the potentially confounding, combined effects of vascular activity and partial-volume averaging.

  6. Methods for the correction of vascular artifacts in PET O-15 water brain-mapping studies

    International Nuclear Information System (INIS)

    Chen, K.; Reiman, E.M.; Good Samaritan Regional Medical Center, Phoenix, AZ; Lawson, M.; Yun, L.S.; Bandy, D.

    1996-01-01

    While positron emission tomographic (PET) measurements of regional cerebral blood flow (rCBF) can be used to map brain regions that are involved in normal and pathological human behaviors, measurements in the anteromedial temporal lobe can be confounded by the combined effects of radiotracer activity in neighboring arteries and partial-volume averaging. The authors now describe two simple methods to address this vascular artifact. One method utilizes the early frames of a dynamic PET study, while the other method utilizes a coregistered magnetic resonance image (MRI) to characterize the vascular region of interest (VROI). Both methods subsequently assign a common value to each pixel in the VROI for the control scan and the activation scan. To study the vascular artifact and to demonstrate the ability of the proposed methods correcting the vascular artifact, four dynamic PET scans were performed in a single subject during the same behavioral state. For each of the four scans, a vascular scan containing vascular activity was computed as the summation of the images acquired 0--60 s after radiotracer administrations, and a control scan containing minimal vascular activity was computed as the summation of the images acquired 20--80 s after radiotracer administration. t-score maps calculated from the four pairs of vascular and control scans were used to characterize regional blood flow differences related to vascular activity before and after the applications of each vascular artifact correction method. Both methods eliminated the observed differences in vascular activity, as well as the vascular artifact observed in the anteromedial temporal lobes. Using PET data from a study of normal human emotion, these methods permitted us to identify rCBF increases in the anteromedial temporal lobe free from the potentially confounding, combined effects of vascular activity and partial-volume averaging

  7. Vascular input function correction of inflow enhancement for improved pharmacokinetic modeling of liver DCE-MRI.

    Science.gov (United States)

    Ning, Jia; Schubert, Tilman; Johnson, Kevin M; Roldán-Alzate, Alejandro; Chen, Huijun; Yuan, Chun; Reeder, Scott B

    2018-06-01

    To propose a simple method to correct vascular input function (VIF) due to inflow effects and to test whether the proposed method can provide more accurate VIFs for improved pharmacokinetic modeling. A spoiled gradient echo sequence-based inflow quantification and contrast agent concentration correction method was proposed. Simulations were conducted to illustrate improvement in the accuracy of VIF estimation and pharmacokinetic fitting. Animal studies with dynamic contrast-enhanced MR scans were conducted before, 1 week after, and 2 weeks after portal vein embolization (PVE) was performed in the left portal circulation of pigs. The proposed method was applied to correct the VIFs for model fitting. Pharmacokinetic parameters fitted using corrected and uncorrected VIFs were compared between different lobes and visits. Simulation results demonstrated that the proposed method can improve accuracy of VIF estimation and pharmacokinetic fitting. In animal study results, pharmacokinetic fitting using corrected VIFs demonstrated changes in perfusion consistent with changes expected after PVE, whereas the perfusion estimates derived by uncorrected VIFs showed no significant changes. The proposed correction method improves accuracy of VIFs and therefore provides more precise pharmacokinetic fitting. This method may be promising in improving the reliability of perfusion quantification. Magn Reson Med 79:3093-3102, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  8. Startup, Shutdown, & Malfunction (SSM) Emissions

    Science.gov (United States)

    EPA issued a final action to ensure states have plans in place that are fully consistent with the Clean Air Act and recent court decisions concerning startup, shutdown and malfunction (SSM) operations.

  9. 40 CFR 63.1111 - Startup, shutdown, and malfunction.

    Science.gov (United States)

    2010-07-01

    ... corrective action taken to restore malfunctioning process and air pollution control equipment to its normal... such affected source (including associated air pollution control equipment and CPMS) in a manner consistent with safety and good air pollution control practices for minimizing emissions to the extent...

  10. An expert system for sensor data validation and malfunction detection

    International Nuclear Information System (INIS)

    Hashemi, S.; Hajek, B.K.; Miller, D.W.; Chandrasekaran, B.; Punch, W.F. III.

    1987-01-01

    During recent years, applications of expert systems in different fields of engineering have been under study throughout the world. At the Ohio State University, the theories developed by the Laboratory for Artificial Intelligence Research (LAIR) have been implemented for nuclear power plants and chemical processing systems. For nuclear power plants, these techniques have been further developed to reach diagnostic conclusions about malfunctions and faulty sensors, as well as to suggest corrective actions about the malfunctions. This paper concentrates on the AI applications to plant diagnosis and faulty sensor identifications. To achieve the above goals without adding extra sensors in a plant, the use of unlike sensor data (such as relationships between pressure and temperature in a Boiling Water Reactor (BWR)) and diagnostic conclusions about malfunctions as backups for suspicious sensors has been made. This extra evidence is readily available throughout the plant and is not generally used to backup suspicious sensor data in any manner

  11. Correct diagnosis of vascular encasement and longitudinal extension of hilar cholangiocarcinoma by four-channel multidetector-row computed tomography

    International Nuclear Information System (INIS)

    Okumoto, Tadayuki; Yamada, Takayuki; Sato, Akihiro

    2009-01-01

    Accurate diagnosis of local invasion of hilar cholangiocarcinomas is challenging due to their small size and the anatomic complexity of the hepatic hilar region. On the other hand, the correct diagnosis of local invasion is essential for assuring the possibility of curative surgery. The purpose of this study was to evaluate the feasibility of four-channel multidetector-row computed tomography (MDCT) in the assessment of vascular and bile duct involvement, by which we could obtain useful information for the surgical management of hilar cholangiocarcinoma. The subjects were 18 patients for whom the extent of tumor invasion was surgically and pathologically confirmed. All patients underwent preoperative multiphasic CT scanning by MDCT. Arterial and portal dominant phases were acquired using a detector configuration of 1.25 mm x 4 mm, and both axial and multiplanar reconstructed images were interpreted. Longitudinal extension was evaluated up to second-order branches. Vascular invasion is considered to be the degree of tumor contiguity to the hepatic arteries and portal vein and was graded by CT. The longitudinal extension was correctly diagnosed in 14 patients (77.8%). Hepatic artery invasion was correctly diagnosed in 17 patients with sensitivity of 100% and specificity of 90%, respectively. Portal vein invasion was correctly diagnosed in 47 of 51 branches with sensitivity and specificity of 92.3% and 90.2%, respectively. Multiplanar reconstructed images contributed to the correct diagnosis for both vascular encasement and longitudinal tumor extension. In conclusion, MDCT is useful in preoperative evaluation of hilar cholangiocarcinoma, especially when combined with multiplanar reconstructed images. (author)

  12. Control Rod Malfunction at the NRAD Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Thomas L. Maddock

    2010-05-01

    The neutron Radiography Reactor (NRAD) is a training, research, and isotope (TRIGA) reactor located at the INL. The reactor is normally shut down by the insertion of three control rods that drop into the core when power is removed from electromagnets. During a routine shutdown, indicator lights on the console showed that one of the control rods was not inserted. It was initially thought that the indicator lights were in error because of a limit switch that was out of adjustment. Through further testing, it was determined that the control rod did not drop when the scram switch was initially pressed. The control rod anomaly led to a six month shutdown of the reactor and an in depth investigation of the reactor protective system. The investigation looked into: scram switch operation, console modifications, and control rod drive mechanisms. A number of latent issues were discovered and corrected during the investigation. The cause of the control rod malfunction was found to be a buildup of corrosion in the control rod drive mechanism. The investigation resulted in modifications to equipment, changes to both operation and maintenance procedures, and additional training. No reoccurrences of the problem have been observed since corrective actions were implemented.

  13. Correction

    DEFF Research Database (Denmark)

    Pinkevych, Mykola; Cromer, Deborah; Tolstrup, Martin

    2016-01-01

    [This corrects the article DOI: 10.1371/journal.ppat.1005000.][This corrects the article DOI: 10.1371/journal.ppat.1005740.][This corrects the article DOI: 10.1371/journal.ppat.1005679.].......[This corrects the article DOI: 10.1371/journal.ppat.1005000.][This corrects the article DOI: 10.1371/journal.ppat.1005740.][This corrects the article DOI: 10.1371/journal.ppat.1005679.]....

  14. Anaesthetic Management of a 1-Month-Old Puppy Undergoing Lateral Thoracotomy for Vascular Ring Anomaly Correction

    Directory of Open Access Journals (Sweden)

    Olga Martin Jurado

    2011-01-01

    Full Text Available A 1-month-old male flat-coated retriever was anaesthetized for correction of oesophageal constriction caused by a vascular ring anomaly. Anaesthesia was uneventfully induced with intravenous fentanyl, diazepam, and propofol and maintained with isoflurane in oxygen and air. An intercostal block with bupivacaine and lidocaine was performed, and additional analgesia with an infusion of fentanyl was provided. Fluid therapy consisted in 5% glucose in lactated Ringer’s solution and hetastarch 6%, which proved adequate to maintain normoglycemia and normovolemia. A lateral thoracotomy was performed, and the ligamentum arteriosum was ligated. Intraoperatively, heart rate (HR varied between 120 and 180 beats min−1 without accompanying changes in blood pressure. No arrhythmias were observed or bleeding occurred. The dog recovered uneventfully. Postoperative analgesia consisted in fentanyl infusion adjusted to the patient's requirement and metamizol. This paper describes for the first time the use of balanced anaesthesia and multimodal analgesia in a paediatric dog undergoing thoracotomy.

  15. Partial volume effect estimation and correction in the aortic vascular wall in PET imaging

    International Nuclear Information System (INIS)

    Burg, S; Le Guludec, D; Dupas, A; Stute, S; Dieudonné, A; Huet, P; Buvat, I

    2013-01-01

    We evaluated the impact of partial volume effect (PVE) in the assessment of arterial diseases with 18 FDG PET. An anthropomorphic digital phantom enabling the modeling of aorta related diseases like atherosclerosis and arteritis was used. Based on this phantom, we performed GATE Monte Carlo simulations to produce realistic PET images with a known organ segmentation and ground truth activity values. Images corresponding to 15 different activity-concentration ratios between the aortic wall and the blood and to 7 different wall thicknesses were generated. Using the PET images, we compared the theoretical wall-to-blood activity-concentration ratios (WBRs) with the measured WBRs obtained with five measurement methods: (1) measurement made by a physician (Expert), (2) automated measurement supposed to mimic the physician measurements (Max), (3) simple correction based on a recovery coefficient (Max-RC), (4) measurement based on an ideal VOI segmentation (Mean-VOI) and (5) measurement corrected for PVE using an ideal geometric transfer matrix (GTM) method. We found that Mean-VOI WBRs values were strongly affected by PVE. WBRs obtained by the physician measurement, by the Max method and by the Max-RC method were more accurate than WBRs obtained with the Mean-VOI approach. However Expert, Max and Max-RC WBRs strongly depended on the wall thickness. Only the GTM corrected WBRs did not depend on the wall thickness. Using the GTM method, we obtained more reproducible ratio values that could be compared across wall thickness. Yet, the feasibility of the implementation of a GTM-like method on real data remains to be studied. (paper)

  16. Correction

    CERN Multimedia

    2002-01-01

    Tile Calorimeter modules stored at CERN. The larger modules belong to the Barrel, whereas the smaller ones are for the two Extended Barrels. (The article was about the completion of the 64 modules for one of the latter.) The photo on the first page of the Bulletin n°26/2002, from 24 July 2002, illustrating the article «The ATLAS Tile Calorimeter gets into shape» was published with a wrong caption. We would like to apologise for this mistake and so publish it again with the correct caption.

  17. The effect of ageing on fMRI: Correction for the confounding effects of vascular reactivity evaluated by joint fMRI and MEG in 335 adults

    Science.gov (United States)

    Henson, Richard N. A.; Tyler, Lorraine K.; Davis, Simon W.; Shafto, Meredith A.; Taylor, Jason R.; Williams, Nitin; Cam‐CAN; Rowe, James B.

    2015-01-01

    of age on task‐based activation studies with fMRI do not survive correction for changes in vascular reactivity, and are likely to have been overestimated in previous fMRI studies of ageing. The results from the mediation analysis demonstrate that RSFA is modulated by measures of vascular function and is not driven solely by changes in the variance of neural activity. Based on these findings we propose that the RSFA scaling method is articularly useful in large scale and longitudinal neuroimaging studies of ageing, or with frail participants, where alternative measures of vascular reactivity are impractical. Hum Brain Mapp 36:2248–2269, 2015. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:25727740

  18. Correction

    Directory of Open Access Journals (Sweden)

    2012-01-01

    Full Text Available Regarding Gorelik, G., & Shackelford, T.K. (2011. Human sexual conflict from molecules to culture. Evolutionary Psychology, 9, 564–587: The authors wish to correct an omission in citation to the existing literature. In the final paragraph on p. 570, we neglected to cite Burch and Gallup (2006 [Burch, R. L., & Gallup, G. G., Jr. (2006. The psychobiology of human semen. In S. M. Platek & T. K. Shackelford (Eds., Female infidelity and paternal uncertainty (pp. 141–172. New York: Cambridge University Press.]. Burch and Gallup (2006 reviewed the relevant literature on FSH and LH discussed in this paragraph, and should have been cited accordingly. In addition, Burch and Gallup (2006 should have been cited as the originators of the hypothesis regarding the role of FSH and LH in the semen of rapists. The authors apologize for this oversight.

  19. Correction

    CERN Multimedia

    2002-01-01

    The photo on the second page of the Bulletin n°48/2002, from 25 November 2002, illustrating the article «Spanish Visit to CERN» was published with a wrong caption. We would like to apologise for this mistake and so publish it again with the correct caption.   The Spanish delegation, accompanied by Spanish scientists at CERN, also visited the LHC superconducting magnet test hall (photo). From left to right: Felix Rodriguez Mateos of CERN LHC Division, Josep Piqué i Camps, Spanish Minister of Science and Technology, César Dopazo, Director-General of CIEMAT (Spanish Research Centre for Energy, Environment and Technology), Juan Antonio Rubio, ETT Division Leader at CERN, Manuel Aguilar-Benitez, Spanish Delegate to Council, Manuel Delfino, IT Division Leader at CERN, and Gonzalo León, Secretary-General of Scientific Policy to the Minister.

  20. Sub-clinical middle ear malfunctions in elderly patients; prevalence ...

    African Journals Online (AJOL)

    ... absent acoustic reflex. Keywords: Middle ear malfunctions, elderly patients. ... hearing loss, had audiometric changes suggestive of such. We regarded such .... predictors of silent middle ear malfunction (control for Age and Sex). Variable.

  1. Correction

    Directory of Open Access Journals (Sweden)

    2014-01-01

    Full Text Available Regarding Tagler, M. J., and Jeffers, H. M. (2013. Sex differences in attitudes toward partner infidelity. Evolutionary Psychology, 11, 821–832: The authors wish to correct values in the originally published manuscript. Specifically, incorrect 95% confidence intervals around the Cohen's d values were reported on page 826 of the manuscript where we reported the within-sex simple effects for the significant Participant Sex × Infidelity Type interaction (first paragraph, and for attitudes toward partner infidelity (second paragraph. Corrected values are presented in bold below. The authors would like to thank Dr. Bernard Beins at Ithaca College for bringing these errors to our attention. Men rated sexual infidelity significantly more distressing (M = 4.69, SD = 0.74 than they rated emotional infidelity (M = 4.32, SD = 0.92, F(1, 322 = 23.96, p < .001, d = 0.44, 95% CI [0.23, 0.65], but there was little difference between women's ratings of sexual (M = 4.80, SD = 0.48 and emotional infidelity (M = 4.76, SD = 0.57, F(1, 322 = 0.48, p = .29, d = 0.08, 95% CI [−0.10, 0.26]. As expected, men rated sexual infidelity (M = 1.44, SD = 0.70 more negatively than they rated emotional infidelity (M = 2.66, SD = 1.37, F(1, 322 = 120.00, p < .001, d = 1.12, 95% CI [0.85, 1.39]. Although women also rated sexual infidelity (M = 1.40, SD = 0.62 more negatively than they rated emotional infidelity (M = 2.09, SD = 1.10, this difference was not as large and thus in the evolutionary theory supportive direction, F(1, 322 = 72.03, p < .001, d = 0.77, 95% CI [0.60, 0.94].

  2. Predicting erectile dysfunction following surgical correction of Peyronie's disease without inflatable penile prosthesis placement: vascular assessment and preoperative risk factors.

    Science.gov (United States)

    Taylor, Frederick L; Abern, Michael R; Levine, Laurence A

    2012-01-01

    Surgical therapy remains the gold standard treatment for Peyronie's Disease (PD). Surgical options include plication, grafting, and placement of inflatable penile prosthesis (IPP). Postoperative erectile dysfunction (ED) is a potential complication for PD surgery without IPP. We present our large series follow-up to evaluate preoperative risk factors for postoperative ED. The aim of this study is to evaluate preoperative risk factors for the development of ED following surgical correction of PD taking into account the degree of curvature, graft size, surgical approach, hypertension, hyperlipidemia, diabetes, smoking history, preoperative use of phosphodiesterase 5 inhibitors (PDE5), and preoperative duplex ultrasound findings including peak systolic and end diastolic velocities and resistive index. We identified 218 men undergoing either tunica albuginea plication (TAP) or partial plaque excision with pericardial grafting for PD following a previously published algorithm between November 1992 and April 2007. Preoperative and postoperative erectile function, curvature characteristics, presence of vascular risk factors, and duplex ultrasound findings were available on 109 patients. Our primary outcome measure is the development of ED after surgery for PD. Ten percent of TAP and 21% of plaque excision with grafting patients developed postoperative ED. Neither curve direction (P = 0.76), graft area (P = 0.78), surgical approach (P = 0.12), chronic hypertension (P = 0.51), hyperlipidemia (P = 0.87), diabetes (P = 0.69), nor smoking history (P = 0.99) were significant predictors of postoperative ED. No combination of risk factors was found to be predictive of postoperative ED. Preoperative use of PDE5 was not a significant predictor of postoperative ED (P = 0.33). Neither peak systolic, end diastolic, nor resistive index were significant predictors of ED (P = 0.28, 0.28, and 0.25, respectively). This long-term follow-up of a large published series suggests that neither

  3. Correction of fluorescence for depth-specific optical and vascular properties using reflectance and differential path-length spectroscopy during PDT

    Science.gov (United States)

    van Zaane, F.; Middelburg, T. A.; de Bruijn, H. S.; van der Ploeg-van den Heuvel, A.; de Haas, E. R. M.; Sterenborg, H. J. C. M.; Neumann, H. A. M.; Robinson, D. J.

    2009-06-01

    Introduction: The rate of PpIX fluorescence photobleaching is routinely used as a dose metric for ALA-PDT. Diffuse reflection spectroscopy is often used to account for variations in tissue optical properties at the photosensitizer excitation and emission bands. It can be used to quantify changes in vascular parameters, such as blood volume fraction and saturation, and can aid understanding of tissue response to PDT. The volume and(/or) depth over which these signals are acquired are critical. The aim of this study is to use quantitative reflectance spectroscopy (DPS) to correct fluorescence for changes in tissue optical properties and monitor PDT. Materials & Methods: ALA was topically applied to hairless mice skin and the incubated spot was treated with PDT according to fractionated illumination schemes. DPS measurements of vascular parameters and optical properties were performed directly before and after illumination. Both the differential signal, delivery-and-collection-fiber signal and the collection fiber signal, which all probe different measurement volumes, are analyzed. Results & Conclusions: Analysis of DPS measurements shows that at the depth where most fluorescence originates, there is almost no blood present. During PDT vascular parameters at this depth stay constant. In more oxygenated layers of the tissue, the optical properties do change during PDT, suggesting that only a small part of PpIX fluorescence originates from the interesting depths where vascular response occurs. Correcting fluorescence emission spectra for optical changes at specific depths and not for the total of changes in a larger volume, as is usually done now, can improve PpIX photobleaching based treatment monitoring.

  4. Customizing Extensor Reconstruction in Vascularized Toe Joint Transfers to Finger Proximal Interphalangeal Joints: A Strategic Approach for Correcting Extensor Lag.

    Science.gov (United States)

    Loh, Charles Yuen Yung; Hsu, Chung-Chen; Lin, Cheng-Hung; Chen, Shih-Heng; Lien, Shwu-Huei; Lin, Chih-Hung; Wei, Fu-Chan; Lin, Yu-Te

    2017-04-01

    Vascularized toe proximal interphalangeal joint transfer allows the restoration of damaged joints. However, extensor lag and poor arc of motion have been reported. The authors present their outcomes of treatment according to a novel reconstructive algorithm that addresses extensor lag and allows for consistent results postoperatively. Vascularized toe joint transfers were performed in a consecutive series of 26 digits in 25 patients. The average age was 30.5 years, with 14 right and 12 left hands. Reconstructed digits included eight index, 10 middle, and eight ring fingers. Simultaneous extensor reconstructions were performed and eight were centralization of lateral bands, five were direct extensor digitorum longus-to-extensor digitorum communis repairs, and 13 were central slip reconstructions. The average length of follow-up was 16.7 months. The average extension lag was 17.9 degrees. The arc of motion was 57.7 degrees (81.7 percent functional use of pretransfer toe proximal interphalangeal joint arc of motion). There was no significant difference in the reconstructed proximal interphalangeal joint arc of motion for the handedness (p = 0.23), recipient digits (p = 0.37), or surgical experience in vascularized toe joint transfer (p = 0.25). The outcomes of different techniques of extensor mechanism reconstruction were similar in terms of extensor lag, arc of motion, and reconstructed finger arc of motion compared with the pretransfer toe proximal interphalangeal joint arc of motion. With this treatment algorithm, consistent outcomes can be produced with minimal extensor lag and maximum use of potential toe proximal interphalangeal joint arc of motion. Therapeutic, IV.

  5. Memo has a novel role in S1P signaling and is [corrected] crucial for vascular development.

    Science.gov (United States)

    Kondo, Shunya; Bottos, Alessia; Allegood, Jeremy C; Masson, Regis; Maurer, Francisca G; Genoud, Christel; Kaeser, Patrick; Huwiler, Andrea; Murakami, Masato; Spiegel, Sarah; Hynes, Nancy E

    2014-01-01

    Memo is a conserved protein that was identified as an essential mediator of tumor cell motility induced by receptor tyrosine kinase activation. Here we show that Memo null mouse embryonic fibroblasts (MEFs) are impaired in PDGF-induced migration and this is due to a defect in sphingosine-1-phosphate (S1P) signaling. S1P is a bioactive phospholipid produced in response to multiple stimuli, which regulates many cellular processes. S1P is secreted to the extracellular milieu where it exerts its function by binding a family of G-protein coupled receptors (S1PRs), causing their activation in an autocrine or paracrine manner. The process, termed cell-autonomous S1PR signaling, plays a role in survival and migration. Indeed, PDGF uses cell-autonomous S1PR signaling to promote cell migration; we show here that this S1P pathway requires Memo. Using vascular endothelial cells (HUVECs) with Memo knock-down we show that their survival in conditions of serum-starvation is impaired. Furthermore, Memo loss in HUVECs causes a reduction of junctional VE-cadherin and an increase in sprout formation. Each of these phenotypes is rescued by S1P or S1P agonist addition, showing that Memo also plays an important role in cell-autonomous S1PR signaling in endothelial cells. We also produced conventional and endothelial cell-specific conditional Memo knock-out mouse strains and show that Memo is essential for embryonic development. Starting at E13.5 embryos of both strains display bleeding and other vascular problems, some of the phenotypes that have been described in mouse strains lacking S1PRs. The essential role of Memo in embryonic vascular development may be due in part to alterations in S1P signaling. Taken together our results show that Memo has a novel role in the S1P pathway and that Memo is needed to promote cell-autonomous S1PR activation.

  6. 40 CFR 52.271 - Malfunction, startup, and shutdown regulations.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Malfunction, startup, and shutdown..., startup, and shutdown regulations. (a) The following regulations are disapproved because they would permit... malfunctions and/or fail to sufficiently limit startup and shutdown exemptions to those periods where it is...

  7. Insulin Pump Malfunction During Hospitalization: Two Case Reports.

    Science.gov (United States)

    Faulds, Eileen R; Wyne, Kathleen L; Buschur, Elizabeth O; McDaniel, Jodi; Dungan, Kathleen

    2016-06-01

    Insulin pump malfunctions and failures continue to occur; however, more severe malfunctions such as the "runaway pump" phenomenon are rarely reported. This article describes two cases of pump malfunction in which pump users appear to have received an unsolicited bolus of insulin resulting in severe episodes of hypoglycemia during hospitalization. Both cases of insulin pump malfunction occurred in the inpatient setting at a large academic medical center in the United States. An analysis of the corresponding insulin pump downloads was performed. The Food and Drug Administration's (FDA's) Manufacturer and User Facility Device Experience (MAUDE) database was searched for similar cases involving Medtronic (Northridge, CA) insulin pumps using the terms "pump," "infusion," "insulin AND malfunction AND Medtronic." The two cases described show remarkable similarities, each demonstrating a severe hypoglycemic event preceded by an infusion site change followed by an alarm. In both cases a rapid spraying of insulin was reported. The insulin pump downloads validated much of the patients' and medical staff's descriptions of events. The FDA's MAUDE database search revealed 425 cases meeting our search term criteria. All cases were reviewed. Seven cases were identified involving independent movement of the reservoir piston. The cases detailed are the first to describe an insulin pump malfunction of this nature in the hospital setting involving unsolicited insulin boluses leading to severe hypoglycemia. The cases are particularly compelling in that they were witnessed by medical personnel. Providers and patients should receive instruction education on the recognition and management of insulin pump malfunction.

  8. I and C functional test facility malfunction cause and effect

    International Nuclear Information System (INIS)

    Kwon, Kee Choon.

    1997-06-01

    The objective of I and C function test facility (FTF) is to validate newly developed digital control and protection algorithm, alarm reduction algorithm and the function of operator support system and so on. To realize transient and accident situation in the FTF, the result of the activation of malfunction should be similar to the situation of real nuclear power plants. In this technical report, describe the Group, Malfunction No., Description, Option, Recommendations, Considered in Subroutine, Limitations, Cause, and Effect of the malfunctions implemented in FTF. (author)

  9. Automatic detection and analysis of nuclear plant malfunctions

    International Nuclear Information System (INIS)

    Bruschi, R.; Di Porto, P.; Pallottelli, R.

    1985-01-01

    In this paper a system is proposed, which performs dynamically the detection and analysis of malfunctions in a nuclear plant. The proposed method was developed and implemented on a Reactor Simulator, instead of on a real one, thus allowing a wide range of tests. For all variables under control, a simulation module was identified and implemented on the reactor on-line computer. In the malfunction identification phase all modules run separately, processing plant input variables and producing their output variable in Real-Time; continuous comparison of the computed variables with plant variables allows malfunction's detection. At this moment the second phase can occur: when a malfunction is detected, all modules are connected, except the module simulating the wrong variable, and a fast simulation is carried on, to analyse the consequences. (author)

  10. Startup, Shutdown, & Malfunction (SSM) Emissions at Industrial Facilities

    Science.gov (United States)

    EPA issued a final action to ensure states have plans in place that are fully consistent with the Clean Air Act and recent court decisions concerning startup, shutdown and malfunction (SSM) operations.

  11. Direct means of obtaining CAVI0-a corrected cardio-ankle vascular stiffness index (CAVI)-from conventional CAVI measurements or their underlying variables.

    Science.gov (United States)

    Spronck, Bart; Mestanik, Michal; Tonhajzerova, Ingrid; Jurko, Alexander; Jurko, Tomas; Avolio, Alberto P; Butlin, Mark

    2017-09-21

    Cardio-ankle vascular index (CAVI) as measured using the VaSera device (CAVI VS , Fukuda Denshi), has been proposed as a stiffness index that does not depend on blood pressure. We have recently shown theoretically that CAVI VS still exhibits blood pressure dependence, and proposed the corrected index CAVI 0 . The present study aims to establish a method of calculating [Formula: see text] either (i) from VaSera-reported values of cardiac-brachial and brachial-ankle pulse transit times (tb and tba, respectively) and blood pressure, or (ii) directly from CAVI VS . To derive this method, the relationship among CAVI VS and its scale constants a and b, tb, tba, and blood pressure has to be established. From data of 497 subjects, eight candidate CAVI parameters were defined and calculated, containing all combinations of left or right tb/tba/blood pressure. Candidates were evaluated through correlation with measured left and right CAVI VS . Correlations were compared statistically. Once the correct candidates were determined, two constants (a and b) required for converting CAVI VS to CAVI 0 were estimated through linear regression. Left and right CAVI VS are calculated using left and right tba; however, both left and right CAVI VS are calculated using right brachial blood pressures and right tb. Constants a and b for conversion of CAVI VS to CAVI 0 were estimated to be 0.842 [0.836 0.848] and 0.753 [0.721 0.786] (mean [95%CI]), respectively. Equations to estimate CAVI 0 from CAVI VS , and to directly calculate CAVI 0 from the VaSera output are provided in this paper, as well as in a directly usable spreadsheet supplement. Our results permit straightforward calculation of [Formula: see text] during a study, as well as retrospective estimation of [Formula: see text] from CAVI VS in already published studies or where the original transit time values are not available, paving the way for thorough comparison of CAVI 0 to CAVI VS in clinical and research settings. Novelty and

  12. Detection of thermocouple malfunction in the Beacon system

    International Nuclear Information System (INIS)

    Morita, T.; Heibel, M.D.; Congedo, T.V.

    1992-01-01

    The BEACON system uses Core Exit Thermocouples (T/C) extensively for continuous radial power distribution monitoring. The T/C's are used to adjust the reference power distribution generated by the BEACON system to match the current radial power distribution. T/C reliability, repeatability, and relative accuracy have been very satisfactory. However, it is very important to detect any T/C malfunctions during operation, since a T/C signal change caused by an undetected malfunction can lead to serious errors in the radial power distribution developed by BEACON. A simple procedure has been developed which is capable of discriminating between changes in T/C signals caused by actual changes in reactor conditions and signal changes caused by T/C malfunctions

  13. The concept of explosives malfunctioning in rock blasting

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Q.

    1993-11-01

    The purpose is to identify the critical conditions that cause malfunctioning for some commonly used explosives. Experiments are described that measure sympathetic detonation, desensitization, and cut-offs for two variables: spacing and delay. Explosive malfunctioning is depicted on a delay spacing chart that has different regions. On the chart, the shape and size of each region can vary from one explosive to another. Results are presented from over 70 blasts, that were conducted in the underground drift at the CANMET Experimental Mine, to identify the malfunctioning characteristics of specific emulsion, water gel, and dynamite explosives. For each experiment, two parallel blastholes (with diameter of 32 mm and depth of 1.7 m) were drilled downwards, and full coupling was achieved. The results are presented for the three types of explosives tested. 11 refs., 7 figs.

  14. Malfunctioning Plastic Biliary Endoprosthesis: Percutaneous Transhepatic Balloon Pulling Technique

    Directory of Open Access Journals (Sweden)

    Umberto G. Rossi

    2013-01-01

    Full Text Available Percutaneous transhepatic removal techniques for malfunctioning plastic biliary endoprosthesis are considered safe and efficient second-line strategies, when endoscopic procedures are not feasible. We describe the percutaneous transhepatic balloon pulling technique in a patient with an unresectable malignant hilar cholangiocarcinoma.

  15. Dealing with Malfunction: Locus of Control in Web-Conferencing

    Science.gov (United States)

    Klebl, Michael

    2014-01-01

    This paper considers how students deal with malfunctions that occur during the use of web conferencing systems in learning arrangements. In a survey among participants in online courses that make use of a web-conferencing system (N = 129), the relationship between a preference for internal or external locus of control and the perception of…

  16. Excessive heat removal due to feedwater system malfunction

    International Nuclear Information System (INIS)

    Beader, D.; Peterlin, G.

    1986-01-01

    Excessive heat removal transient of the Krsko Nuclear Power Plant, caused by steam generators feedwater system malfunctions was simulated by RELAP5/MOD1 computer code. The results are increase of power and reactor scram caused by high-high steam generator level. (author)

  17. Classification system for reporting events involving human malfunctions

    International Nuclear Information System (INIS)

    Rasmussen, J.; Pedersen, O.M.; Mancini, G.; Carnino, A.; Griffon, M.; Gagnolet, P.

    1981-03-01

    The report describes a set of categories for reporting industrial incidents and events involving human malfunction. The classification system aims at ensuring information adequate for improvement of human work situations and man-machine interface systems and for attempts to quantify ''human error'' rates. The classification system has a multifacetted non-hierarchial structure and its compatibility with Ispra's ERDS classification is described. The collection of the information in general and for quantification purposes are discussed. 24 categories, 12 of which being human factors oriented, are listed with their respective subcategories, and comments are given. Underlying models of human data processes and their typical malfunctions and of a human decision sequence are described. (author)

  18. Classification system for reporting events involving human malfunctions

    DEFF Research Database (Denmark)

    Rasmussen, Jens; Pedersen, O.M.; Mancini, G.

    1981-01-01

    The report describes a set of categories for reporting indus-trial incidents and events involving human malfunction. The classification system aims at ensuring information adequate for improvement of human work situations and man-machine interface systems and for attempts to quantify "human error......" rates. The classification system has a multifacetted non-hierarchical struc-ture and its compatibility with Isprals ERDS classification is described. The collection of the information in general and for quantification purposes are discussed. 24 categories, 12 of which being human factors oriented......, are listed with their respective subcategories, and comments are given. Underlying models of human data processes and their typical malfunc-tions and of a human decision sequence are described....

  19. Whole-brain vascular reactivity measured by fMRI using hyperventilation and breath-holding tasks: efficacy of 3D prospective acquisition correction (3D-PACE) for head motion

    International Nuclear Information System (INIS)

    Naganawa, Shinji; Koshikawa, Tokiko; Fukatsu, Hiroshi; Ishigaki, Takeo; Maruyama, Katsuya; Takizawa, Osamu

    2004-01-01

    Functional MR imaging (fMRI) study using hyperventilation and breath-holding task has been reported to be one of the non-invasive methods to examine whole-brain vascular reactivity. The purpose of this study was to evaluate the efficacy of a method for 3D prospective detection and correction of head motion (3D-PACE) in a study of whole-brain vascular reactivity using hyperventilation and breath-holding tasks. Eight healthy volunteers were scanned using an fMRI protocol of hyperventilation and breath-holding task blocks at 3 T in separate runs with and without 3D-PACE. In two subjects, two more runs with and without 3D-PACE were repeated. The mean total number of activated voxels ± standard deviation was 26,405.3±1,822.2 in the run with 3D-PACE and 17,329.9±2,766.3 in the run without 3D-PACE (P<0.05), although there is some intersubject variation regarding the effect of 3D-PACE. In the two subjects whose performed two more runs, the number of activated voxels were smaller in the run without 3D-PACE than even in the run with 3D-PACE performed later. We conclude that 3D-PACE is beneficial for fMRI studies of whole-brain vascular reactivity induced by hyperventilation and breath-holding. (orig.)

  20. Malfunctions of Implantable Cardiac Devices in Patients Receiving Proton Beam Therapy: Incidence and Predictors

    International Nuclear Information System (INIS)

    Gomez, Daniel R.; Poenisch, Falk; Pinnix, Chelsea C.; Sheu, Tommy; Chang, Joe Y.; Memon, Nada; Mohan, Radhe; Rozner, Marc A.; Dougherty, Anne H.

    2013-01-01

    Purpose: Photon therapy has been reported to induce resets of implanted cardiac devices, but the clinical sequelae of treating patients with such devices with proton beam therapy (PBT) are not well known. We reviewed the incidence of device malfunctions among patients undergoing PBT. Methods and Materials: From March 2009 through July 2012, 42 patients with implanted cardiac implantable electronic devices (CIED; 28 pacemakers and 14 cardioverter-defibrillators) underwent 42 courses of PBT for thoracic (23, 55%), prostate (15, 36%), liver (3, 7%), or base of skull (1, 2%) tumors at a single institution. The median prescribed dose was 74 Gy (relative biological effectiveness; range 46.8-87.5 Gy), and the median distance from the treatment field to the CIED was 10 cm (range 0.8-40 cm). Maximum proton and neutron doses were estimated for each treatment course. All CIEDs were checked before radiation delivery and monitored throughout treatment. Results: Median estimated peak proton and neutron doses to the CIED in all patients were 0.8 Gy (range 0.13-21 Gy) and 346 Sv (range 11-1100 mSv). Six CIED malfunctions occurred in 5 patients (2 pacemakers and 3 defibrillators). Five of these malfunctions were CIED resets, and 1 patient with a defibrillator (in a patient with a liver tumor) had an elective replacement indicator after therapy that was not influenced by radiation. The mean distance from the proton beam to the CIED among devices that reset was 7.0 cm (range 0.9-8 cm), and the mean maximum neutron dose was 655 mSv (range 330-1100 mSv). All resets occurred in patients receiving thoracic PBT and were corrected without clinical incident. The generator for the defibrillator with the elective replacement indicator message was replaced uneventfully after treatment. Conclusions: The incidence of CIED resets was about 20% among patients receiving PBT to the thorax. We recommend that PBT be avoided in pacing-dependent patients and that patients with any type of CIED receiving

  1. Risk factors and possible mechanisms of superior vena cava intravenous port malfunction.

    Science.gov (United States)

    Wu, Ching-Yang; Hu, Han-Chung; Ko, Po-Jen; Fu, Jui-Ying; Wu, Ching-Feng; Liu, Yun-Hen; Li, Hao-Jui; Kao, Tsung-Chi; Kao, Kuo-Chin; Yu, Sheng-Yueh; Chang, Chee-Jen; Hsieh, Hong-Chang

    2012-05-01

    To identify the risk factors leading to catheter malfunction. Reliable venous access is crucial for cancer patients. Malfunction of intravenous ports may lead to discontinuation of treatment and repeated interventions. We retrospectively reviewed the independent risk factors for catheter malfunction among patients receiving intravenous port implantations. A total of 1508 procedures were included from the calendar year 2006, and clinical data and chest plain films were analyzed. The patients were followed-up until June 30, 2010. For patients still alive, the last outpatient follow-up date was considered as the end point. For the remaining patients, the date of death or discharge against advice was considered as the end points. The risk factors for catheter malfunction were then evaluated. The intervention-free periods of the malfunction group and nonmalfunction group were 317 and 413 days, respectively. Statistical analyses showed that the Nut-Catheter Angle was the only risk factor for catheter malfunction (P = 0.001). A logistic model also confirmed that the Nut-Catheter Angle was the only risk factor for catheter malfunction (P risk for catheter malfunction. Catheter impingement caused by inadequate pocket creation and port implantation lead to compromised catheter lumen and difficulty flushing. The possibility of retained blood and medications increased thin thrombotic biofilm formation and medication precipitation. Catheter malfunctions can be avoided by using proper surgical techniques and adequate maintenance.

  2. Classification system for reporting events involving human malfunctions

    International Nuclear Information System (INIS)

    Rasmussen, J.; Pedersen, O.M.; Mancini, G.

    1981-01-01

    The report describes a set of categories for reporting industrial incidents and events involving human malfunction. The classification system aims at ensuring information adequate for improvement of human work situations and man-machine interface systems and for attempts to quantify ''human error'' rates. The classification system has a multifacetted non-hierarchical structure and its compatibility with Ispra's ERDS classification is described. The collection of the information in general and for quantification purposes are discussed. 24 categories, 12 of which being human factors-oriented, are listed with their respective subcategories, and comments are given. Underlying models of human data process and their typical malfuntions and of a human decision sequence are described. The work reported is a joint contribution to the CSNI Group of Experts on Human Error Data and Assessment

  3. Endoscopic removal of malfunctioning biliary self-expandable metallic stents.

    Science.gov (United States)

    Familiari, Pietro; Bulajic, Milutin; Mutignani, Massimiliano; Lee, Linda S; Spera, Gianluca; Spada, Cristiano; Tringali, Andrea; Costamagna, Guido

    2005-12-01

    Endoscopic removal of malfunctioning self-expandable metallic biliary stents (SEMS) is difficult and not well described. The aim of this study is to review the indications, the techniques, and the results of SEMS removal in a cohort of patients with malfunctioning stents. All patients who underwent an attempt at endoscopic removal of biliary SEMS over a 5-year period were retrospectively identified. The main indications for SEMS removal were the following: distal migration of the stent or impaction to the duodenum, impaction into the bile-duct wall, tissue ingrowth, and inappropriate length of the stent causing occlusion of intrahepatic ducts. SEMS were removed by using foreign-body forceps or polypectomy snares. Endoscopic removal of 39 SEMS (13 uncovered and 26 covered) was attempted in 29 patients (17 men; mean age, 66 years). SEMS extraction was attempted after a mean of 7.5 months (8.75 months standard deviation) post-SEMS insertion. Removal was successful in 20 patients (68.9%) and in 29 SEMS (74.3%). Covered SEMS were effectively removed more frequently than uncovered ones: 24 of 26 (92.3%) and 5 of 13 (38.4%), respectively (p < 0.05). No major complications were recorded. Multivariate analysis showed that the time interval between insertion and removal, SEMS length, stent-mesh design (zigzag vs. interlaced), and indication for removal were not predictive of success at stent removal. Endoscopic removal of biliary SEMS is feasible and safe in more than 70% of cases. Because only 38% of uncovered SEMS were removable, the presence of a stent covering is the only factor predictive of successful stent extraction. The presence of diffuse and severe ingrowth was the main feature limiting SEMS removal.

  4. Malfunction of the inner ear is the most frequent cause of dizziness

    DEFF Research Database (Denmark)

    Klokker, Mads; Vesterhauge, Søren

    2013-01-01

    Half of all dizziness patients suffer from a malfunction of the inner ear and benign paroxysmal positional vertigo causes 25-30% of these malfunctions. During the latest two decades new vestibular test equipment has been developed and has made it possible to refine the vestibular diagnoses...

  5. 33 CFR 149.125 - What are the requirements for the malfunction detection system?

    Science.gov (United States)

    2010-07-01

    ... malfunction detection system? 149.125 Section 149.125 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... Pollution Prevention Equipment § 149.125 What are the requirements for the malfunction detection system? (a... Commandant (CG-5) will evaluate proposed leak-detection systems for natural gas on an individual basis. ...

  6. 40 CFR 60.2918 - What happens during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Performance Testing ...

  7. 40 CFR 63.2852 - What is a startup, shutdown, and malfunction plan?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 12 2010-07-01 2010-07-01 true What is a startup, shutdown, and... Production Compliance Requirements § 63.2852 What is a startup, shutdown, and malfunction plan? You must...)(2) malfunction period, or the § 63.2850(c)(2) or (d)(2) initial startup period. The SSM plan must...

  8. 40 CFR 60.2120 - What happens during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... 1, 2001 Emission Limitations and Operating Limits § 60.2120 What happens during periods of startup... during CISWI unit startups, shutdowns, or malfunctions. (b) Each malfunction must last no longer than 3...

  9. 40 CFR 60.2685 - What happens during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during CISWI unit startups, shutdowns, or malfunctions. (b) Each...

  10. 40 CFR 65.6 - Startup, shutdown, and malfunction plan and procedures.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Startup, shutdown, and malfunction... (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE General Provisions § 65.6 Startup... Group 2A or Group 2B process vents. (b) Startup, shutdown, and malfunction plan—(1) Description and...

  11. 40 CFR 60.3025 - What happens during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What happens during periods of startup... during periods of startup, shutdown, and malfunction? The emission limitations and operating limits apply at all times except during OSWI unit startups, shutdowns, or malfunctions. Model Rule—Performance...

  12. Actividades para la corrección de la apraxia constructiva en pacientes con secuelas de enfermedad cerebro-vascular = Activities for the correction of constructive apraxia in patients with sequels of brain-vascular illness

    Directory of Open Access Journals (Sweden)

    Torres Aguilar, Maydane

    2008-09-01

    Full Text Available RESUMENObjetivo: Evaluar un sistema de actividades realizadas para la corrección y compensación de la apraxia constructiva después de la exploración neuropsicológica. Método: Con el propósito de evaluar este sistema de actividades, se realizó un estudio prospectivo experimental con 15 pacientes que permanecieron en el Centro Internacional de Investigaciones y Restauración Neurológica (CIREN durante un período de 54 días que recibieron tratamiento defectológico (Terapia Ocupacional diario. En consecuencia se aplicó una escala evaluativa pre y post-intervención terapéutica comparándose los resultados.Resultados: A través de la escala de puntaje aplicada se obtuvo un incremento de recuperación en cuanto a la realización de las actividades sin niveles de ayuda ni modelos previos de un 93,4% post-intervención, como promedio, en los pacientes analizados.Conclusiones: Se observó una mejor asociación entre la idea del movimiento y la ejecución motora así como entre la percepción visual y la acción apropiada, después de la intervención.SUMMARYA great number of patients with Encephalic Static Lesions suffer psychic and motor alterations that avoid him to develop it more usually possible in his social environment. One of the psychic alterations that are frequently presented is the constructive apraxia which can appear in different grades, depending among other factors, of the severity of the damage. This unchains difficulties that go from the less complex, as the reproduction of drawings until others of more complexity like daily basic activities. Objectives: Evaluate system of activities for correction and/or compensation the constructive apraxia after neuro-psychological exploration. Methods and Material: With the proposal to check the effectiveness of this system of activities we carry out a prospective and experimental study with 15 patients that were in CIREN (International Centre of Research and Neurological Restoration

  13. Connecting Malfunctioning Glial Cells and Brain Degenerative Disorders.

    Science.gov (United States)

    Kaminsky, Natalie; Bihari, Ofer; Kanner, Sivan; Barzilai, Ari

    2016-06-01

    The DNA damage response (DDR) is a complex biological system activated by different types of DNA damage. Mutations in certain components of the DDR machinery can lead to genomic instability disorders that culminate in tissue degeneration, premature aging, and various types of cancers. Intriguingly, malfunctioning DDR plays a role in the etiology of late onset brain degenerative disorders such as Parkinson's, Alzheimer's, and Huntington's diseases. For many years, brain degenerative disorders were thought to result from aberrant neural death. Here we discuss the evidence that supports our novel hypothesis that brain degenerative diseases involve dysfunction of glial cells (astrocytes, microglia, and oligodendrocytes). Impairment in the functionality of glial cells results in pathological neuro-glial interactions that, in turn, generate a "hostile" environment that impairs the functionality of neuronal cells. These events can lead to systematic neural demise on a scale that appears to be proportional to the severity of the neurological deficit. Copyright © 2016 The Authors. Production and hosting by Elsevier Ltd.. All rights reserved.

  14. Connecting Malfunctioning Glial Cells and Brain Degenerative Disorders

    Directory of Open Access Journals (Sweden)

    Natalie Kaminsky

    2016-06-01

    Full Text Available The DNA damage response (DDR is a complex biological system activated by different types of DNA damage. Mutations in certain components of the DDR machinery can lead to genomic instability disorders that culminate in tissue degeneration, premature aging, and various types of cancers. Intriguingly, malfunctioning DDR plays a role in the etiology of late onset brain degenerative disorders such as Parkinson’s, Alzheimer’s, and Huntington’s diseases. For many years, brain degenerative disorders were thought to result from aberrant neural death. Here we discuss the evidence that supports our novel hypothesis that brain degenerative diseases involve dysfunction of glial cells (astrocytes, microglia, and oligodendrocytes. Impairment in the functionality of glial cells results in pathological neuro-glial interactions that, in turn, generate a “hostile” environment that impairs the functionality of neuronal cells. These events can lead to systematic neural demise on a scale that appears to be proportional to the severity of the neurological deficit.

  15. Malfunction Rates of Bird Flight Diverters on Powerlines in the Mongolian Gobi

    Directory of Open Access Journals (Sweden)

    Batsuuri Dashnyam

    2016-11-01

    Full Text Available The Oyu Tolgoi (OT project, one of the world’s largest copper and gold mines, is located in Gobi Desert of Mongolia. To help meet its target of Net Positive Impact on key biodiversity features such as the Houbara bustard (Chlamydotis undulata the OT installed bird fl ight diverters (BFDs include spiral and fl apper devices to its power transmission lines to reduce the risk of birds hitting the wires. Despite the many studies demonstrating that BFDs reduce collision rates, we could fi nd no published information on malfunction rates of BFDs. In January 2013, we surveyed the physical function of 1,200 BFDs (e.g. 600 fl appers and 600 spirals in three sample areas on each of four lines of varying voltage and structure. Of the 600 fl appers examined, 123 had malfunctioned within nine months of installation, while the malfunction rate of the 600 spirals studied was zero. Using a Generalized Linear Mixed Model, we found that the rate of fl apper malfunction increased with decreasing fl apper size and power line diameter. Further, the fl apper malfunction rate increased as the distance between poles increased. The cost of replacing malfunctioning BFDs is very high as there are serious health and safety constraints related to working with live wires. Factors aff ecting diverter malfunctioning need to be considered for future powerline projects and our information can serve as basis for developing national standards or regulations for powerline mitigation in Mongolia.

  16. 40 CFR 60.1710 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... during periods of startup, shutdown, and malfunction? 60.1710 Section 60.1710 Protection of Environment... during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or malfunction...

  17. 40 CFR 60.1220 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... during periods of startup, shutdown, and malfunction? 60.1220 Section 60.1220 Protection of Environment... Emission Limits § 60.1220 What happens to the emission limits during periods of startup, shutdown, and... waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or malfunction must...

  18. An expert system for sensor data validation and malfunction detection

    International Nuclear Information System (INIS)

    Hashemi, S.; Hajek, B.K.; Miller, D.W.

    1987-01-01

    Nuclear power plant operation and monitoring in general is a complex task which requires a large number of sensors, alarms and displays. At any instant in time, the operator is required to make a judgment about the state of the plant and to react accordingly. During abnormal situations, operators are further burdened with time constraints. The possibility of an undetected faulty instrumentation line, adds to the complexity of operators' reasoning tasks. Failure of human operators to cope with the conceptual complexity of abnormal situations often leads to more serious malfunctions and further damages to plant (TMI-2 as an example). During these abnormalities, operators rely on the information provided by the plant sensors and associated alarms. Their usefulness however, is quickly diminished by their large number and the extremely difficult task of interpreting and comprehending the information provided by them. The need for an aid to assist the operator in interpreting the available data and diagnosis of problems is obvious. Recent work at the Ohio State University Laboratory of Artificial Intelligence Research (LAIR) and the nuclear engineering program has concentrated on the problem of diagnostic expert systems performance and their applicability to the nuclear power plant domain. There has also been concern about the diagnostic expert systems performance when using potentially invalid sensor data. Because of this research, an expert system has been developed that can perform diagnostic problem solving despite the existence of some conflicting data in the domain. This work has resulted in enhancement of a programming tool, that allows domain experts to create a diagnostic system that will be to some degree, tolerant of bad data while performing diagnosis. This expert system is described here

  19. 40 CFR 1045.110 - How must my engines diagnose malfunctions?

    Science.gov (United States)

    2010-07-01

    ... color except red. Visible malfunction indicators must display “Check Engine,” “Service Engine Soon,” or... engine operation. (d) Store trouble codes in computer memory. Record and store in computer memory any...

  20. On the malfunction of disk-type induction relay under seismic condition

    International Nuclear Information System (INIS)

    Fujita, T.; Shibata, H.; Koizumi, T.

    1985-01-01

    This paper deals with the malfunction of disk-type induction relay. Equations of motion for rotational movement of induction relay was formulated and the dynamic behavior was simulated under various kind of exciting conditions. Experimental verification was also performed using two dimensional shaker table for some actual relays. Sufficient agreement was recognized between experimental and analytical results and consequently the most critical reason to cause the malfunction was pointed out. (orig.)

  1. Effects of a malfunctional column on conventional and FeedCol-simulated moving bed chromatography performance.

    Science.gov (United States)

    Song, Ji-Yeon; Oh, Donghoon; Lee, Chang-Ha

    2015-07-17

    The effects of a malfunctional column on the performance of a simulated moving bed (SMB) process were studied experimentally and theoretically. The experimental results of conventional four-zone SMB (2-2-2-2 configuration) and FeedCol operation (2-2-2-2 configuration with one feed column) with one malfunctional column were compared with simulation results of the corresponding SMB processes with a normal column configuration. The malfunctional column in SMB processes significantly deteriorated raffinate purity. However, the extract purity was equivalent or slightly improved compared with the corresponding normal SMB operation because the complete separation zone of the malfunctional column moved to a lower flow rate range in zones II and III. With the malfunctional column configuration, FeedCol operation gave better experimental performance (up to 7%) than conventional SMB operation because controlling product purity with FeedCol operation was more flexible through the use of two additional operating variables, injection time and injection length. Thus, compared with conventional SMB separation, extract with equivalent or slightly better purity could be produced from FeedCol operation even with a malfunctional column, while minimizing the decrease in raffinate purity (less than 2%). Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Trust and automation: the influence of automation malfunctions and system feedback on operator trust

    International Nuclear Information System (INIS)

    Strand, Stine

    2001-10-01

    Level of operator trust in an automatic system, which is not in accordance with the reliability of the system, might impose serious threats concerning issues of safety, productivity and the well being of the operator. Operator trust is therefore regarded as an important variable in man-machine interaction. The focus of this study was the influence of automatic malfunctions and amount of feedback provided by the automatic system on level of operator trust. The study was conducted in conjunction with the Human Centred Automation 2000-experiment. Two questionnaires attempting to measure operator trust were developed, designed to reflect the dimensions of predictability, dependability and faith. Analysis of the questionnaires demonstrated that they were reliable tools for measurement of operator trust. Factor analysis did not completely confirm the theoretical dimensions of trust, but indicated partial support. Operator trust correlated negatively with workload across situations, and positively with performance in complex situations. The results of the hypotheses tests demonstrated that operator trust gradually decreased after introduction of malfunctions. The effect of different malfunctions was however the opposite of what was expected, with obvious malfunctions reducing trust more than more camouflaged and safety critical malfunctions. Trust in the automatic system in general was lower than trust in specific malfunctioning components. Different interfaces providing different amount of feedback to the operator did not significantly influence level of operator trust. (Author)

  3. VASCULAR SURGERY

    African Journals Online (AJOL)

    2016-06-02

    Jun 2, 2016 ... with the literature from South Africa over the last four decades, and reflects the high rate of interpersonal violence in the country.14,15 As expected, cervical ... via the intact circle of Willis in young patients is the most likely explanation for the lack of strokes. Five patients were referred to the Durban vascular ...

  4. Vascular Disorders

    Science.gov (United States)

    ... All Topics A-Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is a Hand Surgeon? What is a Hand Therapist? Media Find a Hand Surgeon Home Anatomy Vascular Disorders Email to a friend * required fields ...

  5. Treating malfunction filtering bleb with repeated needling combined with adjunctive 5-FU after glaucoma filtration surgery

    Directory of Open Access Journals (Sweden)

    Yi Liu

    2013-07-01

    Full Text Available AIM: To evaluate the therapeutic efficacy of a repeated bleb needling technique combined with subconjunctival injection of 5-FU in eyes with previous glaucoma surgery that had malfunctional filtering blebs. METHODS: A retrospective review of 34 consecutive patients(34 eyesof repeated bleb needling combined with subconjunctival injection of 5-FU in eyes, which had malfunctional filtering blebs after previous glaucoma surgery in our hospital from March 2009 to February 2013 was performed. The intraocular pressures(IOP, shapes of filtering blebs and complications after surgery were analyzed. RESULTS: There was significant reduction of mean IOP from 35.51mmHg to 14.43mmHg(PCONCLUSION: Repeated needling with adjunctive 5-FU proved a highly effective, safe alternative to treat malfunctional filtering blebs after previous glaucoma surgery.

  6. Frequency of pacemaker malfunction associated with monopolar electrosurgery during pulse generator replacement or upgrade surgery.

    Science.gov (United States)

    Lin, Yun; Melby, Daniel P; Krishnan, Balaji; Adabag, Selcuk; Tholakanahalli, Venkatakrishna; Li, Jian-Ming

    2017-08-01

    The aim of this study is to investigate the frequency of electrosurgery-related pacemaker malfunction. A retrospective study was conducted to investigate electrosurgery-related pacemaker malfunction in consecutive patients undergoing pulse generator (PG) replacement or upgrade from two large hospitals in Minneapolis, MN between January 2011 and January 2014. The occurrence of this pacemaker malfunction was then studied by using MAUDE database for all four major device vendors. A total of 1398 consecutive patients from 2 large tertiary referral centers in Minneapolis, MN undergoing PG replacement or upgrade surgery were retrospectively studied. Four patients (0.3% of all patients), all with pacemakers from St Jude Medical (2.8%, 4 of 142) had output failure or inappropriately low pacing rate below 30 bpm during electrosurgery, despite being programmed in an asynchronous mode. During the same period, 1174 cases of pacemaker malfunctions were reported on the same models in MAUDE database, 37 of which (3.2%) were electrosurgery-related. Twenty-four cases (65%) had output failure or inappropriate low pacing rate. The distribution of adverse events was loss of pacing (59.5%), reversion to backup pacing (32.4%), inappropriate low pacing rate (5.4%), and ventricular fibrillation (2.7%). The majority of these (78.5%) occurred during PG replacement at ERI or upgrade surgery. No electrosurgery-related malfunction was found in MAUDE database on 862 pacemaker malfunction cases during the same period from other vendors. Electrosurgery during PG replacement or upgrade surgery can trigger output failure or inappropriate low pacing rate in certain models of modern pacemakers. Cautions should be taken for pacemaker-dependent patients.

  7. An experimental study of emission and combustion characteristics of marine diesel engine with fuel pump malfunctions

    International Nuclear Information System (INIS)

    Kowalski, Jerzy

    2014-01-01

    Presented paper shows the results of the laboratory study on the relation between the chosen malfunctions of a fuel pump and the exhaust gas composition of the marine engine. The object of research is a laboratory four-stroke diesel engine, operated at a constant speed. During the research over 50 parameters were measured with technical condition of the engine recognized as “working properly” and with simulated fuel pump malfunctions. Considered malfunctions are: fuel injection timing delay and two sets of fuel leakages in the fuel pump of one engine cylinder. The results of laboratory research confirm that fuel injection timing delay and fuel leakage in the fuel pump cause relatively small changes in thermodynamic parameters of the engine. Changes of absolute values are so small they may be omitted by marine engines operators. The measuring of the exhaust gas composition shows markedly affection with simulated malfunctions of the fuel pump. Engine operation with delayed fuel injection timing in one cylinder indicates CO 2 emission increase and NOx emission decreases. CO emission increases only at high the engine loads. Fuel leakage in the fuel pump causes changes in CO emission, the increase of CO 2 emission and the decrease of NOx emission. - Highlights: •Chosen malfunctions of the fuel injection pump of marine engine are simulated. •Changes of thermodynamic parameters of marine engine are analyzed. •Changes of CO, CO 2 and NOx emission characteristics of marine engine are analyzed. •Injection pump malfunctions take significant changes in emission characteristics

  8. An ecological interface for supporting situation awareness during malfunction and process and automation

    International Nuclear Information System (INIS)

    Ohtsu, Masataka; Furukawa, Hiroshi; Inagaki, Toshiyuki; Monta, Kazuo

    2000-01-01

    This paper describes the outline of an experiment to investigate the effect of an ecological interface for supporting situation awareness during malfunction of process. We developed an ecological interface and an conventional interface for the simulator SCARLETT of a virtual plant that have two process control modes (automatic process control mode and manual process control mode). The purpose of this experiment is to investigate how interface and process control mode have any effects on situation awareness of human operator during malfunction of process, whether there are any interaction between interface and process control mode. We have been conducted this experiment now. (author)

  9. Vascular dementia

    Science.gov (United States)

    ... poor judgment and loss of ability to recognize danger Using the wrong word, not pronouncing words correctly, ... disease and other dementias. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: ...

  10. Vascular ultrasound.

    Science.gov (United States)

    Pilcher, D B; Ricci, M A

    1998-04-01

    Surgeon-interpreted diagnostic ultrasound has become the preferred screening test and often the definitive test for the diagnosis of arterial stenosis, aneurysm, and venous thrombosis. As a modality for surveillance, its noninvasive quality makes it particularly appealing as the test of choice to screen patients for abdominal aortic aneurysms or to perform follow-up examinations on those patients with a carotid endartectomy or in situ bypass grafts. The increasing reliance on intraoperative duplex imaging of vascular procedures demands that the surgeon learn the skills to perform the studies without a technologist or radiologist to interpret the examination.

  11. Loss of labor time due to malfunctioning ICTs and ICT skill insufficiencies

    NARCIS (Netherlands)

    van Deursen, Alexander Johannes Aloysius Maria; van Dijk, Johannes A.G.M.

    2014-01-01

    Purpose – The purpose of this paper is to unexplore the area of information and communication technology (ICT) use in organizations related to the assumed productivity gains by the use of ICTs. On the one hand, the paper focus on the losses of labor time that are caused by malfunctioning hardware or

  12. 40 CFR 63.310 - Requirements for startups, shutdowns, and malfunctions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Requirements for startups, shutdowns, and malfunctions. 63.310 Section 63.310 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES National Emission Standards for Coke Oven Batteries § 63.310 Requirements for startups, shutdowns...

  13. 40 CFR 1048.110 - How must my engines diagnose malfunctions?

    Science.gov (United States)

    2010-07-01

    ... readily visible to the operator; it may be any color except red. When the MIL goes on, it must display..., the MIL may stay off during later engine operation. (d) Store trouble codes in computer memory. Record and store in computer memory any diagnostic trouble codes showing a malfunction that should illuminate...

  14. Using statistical anomaly detection models to find clinical decision support malfunctions.

    Science.gov (United States)

    Ray, Soumi; McEvoy, Dustin S; Aaron, Skye; Hickman, Thu-Trang; Wright, Adam

    2018-05-11

    Malfunctions in Clinical Decision Support (CDS) systems occur due to a multitude of reasons, and often go unnoticed, leading to potentially poor outcomes. Our goal was to identify malfunctions within CDS systems. We evaluated 6 anomaly detection models: (1) Poisson Changepoint Model, (2) Autoregressive Integrated Moving Average (ARIMA) Model, (3) Hierarchical Divisive Changepoint (HDC) Model, (4) Bayesian Changepoint Model, (5) Seasonal Hybrid Extreme Studentized Deviate (SHESD) Model, and (6) E-Divisive with Median (EDM) Model and characterized their ability to find known anomalies. We analyzed 4 CDS alerts with known malfunctions from the Longitudinal Medical Record (LMR) and Epic® (Epic Systems Corporation, Madison, WI, USA) at Brigham and Women's Hospital, Boston, MA. The 4 rules recommend lead testing in children, aspirin therapy in patients with coronary artery disease, pneumococcal vaccination in immunocompromised adults and thyroid testing in patients taking amiodarone. Poisson changepoint, ARIMA, HDC, Bayesian changepoint and the SHESD model were able to detect anomalies in an alert for lead screening in children and in an alert for pneumococcal conjugate vaccine in immunocompromised adults. EDM was able to detect anomalies in an alert for monitoring thyroid function in patients on amiodarone. Malfunctions/anomalies occur frequently in CDS alert systems. It is important to be able to detect such anomalies promptly. Anomaly detection models are useful tools to aid such detections.

  15. Thermo-characterization of power systems components: a tool to diagnose their malfunctions

    International Nuclear Information System (INIS)

    Zaleta-Aguilar, Alejandro; Royo, Javier; Rangel, Victor H.; Torres-Reyes, Ernestina

    2004-01-01

    Concepts on thermodynamic characterization of power system components are presented in this paper. The aim of this work is to evaluate and diagnose the actual operating condition for existing power plant components. What is more, a Reference Performance State (RPS) for power system components which uses the parameters defined as the enthalpy change, ω, the entropy change, σ and the Mass Flow Ratio design, MFR is put forward. Design information and simulation will help to determine the RPS for each component operating without any malfunction. The RPS can be used to compare, to evaluate and to diagnose the actual operating condition of the plant components so as to detect its possible malfunction. A simulated example of a 105 MW power plant is presented herein so that thermo-characterization of steam turbines, a condenser, a heat exchanger, and a pump is illustrated. The induced and intrinsic component malfunction effects on the RPS are also presented. Their effects are related to the RPS, thereby opening the possibility to apply methodologies to any internal decay and/or induced malfunctions that could appear in an operating component, in terms of the heat rate impact

  16. 40 CFR 62.14645 - What happens during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false What happens during periods of startup... Limits § 62.14645 What happens during periods of startup, shutdown, and malfunction? (a) The emission limitations and operating limits apply at all times except during periods of CISWI unit startup, shutdown, or...

  17. 40 CFR 62.15165 - What happens to the emission limits during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... during periods of startup, shutdown, and malfunction? 62.15165 Section 62.15165 Protection of Environment... emission limits during periods of startup, shutdown, and malfunction? (a) The emission limits of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

  18. 40 CFR 60.1695 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... requirements during periods of startup, shutdown, and malfunction? 60.1695 Section 60.1695 Protection of... Requirements § 60.1695 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

  19. 40 CFR 62.15150 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... requirements during periods of startup, shutdown, and malfunction? 62.15150 Section 62.15150 Protection of... § 62.15150 What happens to the operating requirements during periods of startup, shutdown, and... municipal waste combustion unit startup, shutdown, or malfunction. (b) Each startup, shutdown, or...

  20. 40 CFR 60.1205 - What happens to the operating requirements during periods of startup, shutdown, and malfunction?

    Science.gov (United States)

    2010-07-01

    ... requirements during periods of startup, shutdown, and malfunction? 60.1205 Section 60.1205 Protection of... requirements during periods of startup, shutdown, and malfunction? (a) The operating requirements of this subpart apply at all times except during periods of municipal waste combustion unit startup, shutdown, or...

  1. Peritoneal catheter fixation combined with straight upward tunnel and low implant position to prevent catheter malfunction.

    Science.gov (United States)

    Zhang, Qingyan; Jiang, Chunming; Zhu, Wei; Sun, Cheng; Xia, Yangyang; Tang, Tianfeng; Wan, Cheng; Shao, Qiuyuan; Liu, Jing; Jin, Bo; Zhang, Miao

    2018-03-01

    Catheter malfunction is the main reason for early peritoneal dialysis (PD) technique failure. This study aimed to evaluate the effect of a new surgery technique with catheter fixation to the lower abdominal wall combined with straight upward tunnel and low implant position in reducing catheter malfunction. Patients with end stage renal disease who received PD in our centre from January 2013 to December 2015 were involved in this study. They were randomly divided into three groups according to surgical technique: traditional open surgery group, modified open surgery group and modified open surgery with catheter fixation group. All patients were followed up for six months after surgery. Catheter- related complications were analyzed. A total of 152 patients were involved. Among them, 49 received traditional open surgery (TOS group), 49 received modified open surgery (MOS group), and 54 received modified open surgery with catheter fixation (MOS-F group). During follow-up, no patients (0%) in MOS-F group developed catheter malfunction which was significantly lower than that of the TOS group (0 vs 16.33%, P = 0.002). Although not statistically significant, the incidence of catheter malfunction was lower in MOS-F group than that in MOS group (0 vs 4.08%, P = 0.134). No significant difference was observed in the episodes of infection, bleeding, leakage, inflow or outflow pain, hernia and delayed wound healing among the three groups (all P > 0.05). Catheter fixation combined with straight upward tunnel and low implant position can effectively prevent catheter malfunction in PD catheter placement. © 2016 Asian Pacific Society of Nephrology.

  2. Malfunction of cardiac devices after radiotherapy without direct exposure to ionizing radiation: mechanisms and experimental data.

    Science.gov (United States)

    Zecchin, Massimo; Morea, Gaetano; Severgnini, Mara; Sergi, Elisabetta; Baratto Roldan, Anna; Bianco, Elisabetta; Magnani, Silvia; De Luca, Antonio; Zorzin Fantasia, Anna; Salvatore, Luca; Milan, Vittorino; Giannini, Gianrossano; Sinagra, Gianfranco

    2016-02-01

    Malfunctions of cardiac implantable electronical devices (CIED) have been described after high-energy radiation therapy even in the absence of direct exposure to ionizing radiation, due to diffusion of neutrons (n) causing soft errors in inner circuits. The purpose of the study was to analyse the effect of scattered radiation on different types and models of CIED and the possible sources of malfunctions. Fifty-nine explanted CIED were placed on an anthropomorphous phantom of tissue-equivalent material, and a high-energy photon (15 MV) radiotherapy course (total dose = 70 Gy) for prostate treatment was performed. All devices were interrogated before and after radiation. Radiation dose, the electromagnetic field, and neutron fluence at the CIED site were measured. Thirty-four pacemakers (PM) and 25 implantable cardioverter-defibrillators (ICD) were analysed. No malfunctions were detected before radiation. After radiation a software malfunction was evident in 13 (52%) ICD and 6 (18%) PM; no significant electromagnetic field or photon radiations were detected in the thoracic region. Neutron capture was demonstrated by the presence of the (198)Au((197)Au + n) or (192)Ir((191)Ir + n) isotope activation; it was significantly greater in ICD than in PM and non-significantly greater in damaged devices. A greater effect in St Jude PM (2/2 damaged), Boston (9/11), and St Jude ICD (3/6) and in older ICD models was observed; the year of production was not relevant in PM. High-energy radiation can cause different malfunctions on CIED, particularly ICD, even without direct exposure to ionizing radiation due to scattered radiation of neutrons produced by the linear accelerator. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  3. Cerebrospinal Fluid Lumbar Tapping Utilization for Suspected Ventriculoperitoneal Shunt Under-Drainage Malfunctions.

    Science.gov (United States)

    Lee, Jong-Beom; Ahn, Ho-Young; Lee, Hong-Jae; Yang, Ji-Ho; Yi, Jin-Seok; Lee, Il-Woo

    2017-01-01

    The diagnosis of shunt malfunction can be challenging since neuroimaging results are not always correlated with clinical outcomes. The purpose of this study was to evaluate the efficacy of a simple, minimally invasive cerebrospinal fluid (CSF) lumbar tapping test that predicts shunt under-drainage in hydrocephalus patients. We retrospectively reviewed the clinical and radiological features of 48 patients who underwent routine CSF lumbar tapping after ventriculoperitoneal shunt (VPS) operation using a programmable shunting device. We compared shunt valve opening pressure and CSF lumbar tapping pressure to check under-drainage. The mean pressure difference between valve opening pressure and CSF lumbar tapping pressure of all patients were 2.21±24.57 mmH 2 O. The frequency of CSF lumbar tapping was 2.06±1.26 times. Eighty five times lumbar tapping of 41 patients showed that their VPS function was normal which was consistent with clinical improvement and decreased ventricle size on computed tomography scan. The mean pressure difference in these patients was -3.69±19.20 mmH 2 O. The mean frequency of CSF lumbar tapping was 2.07±1.25 times. Fourteen cases of 10 patients revealed suspected VPS malfunction which were consistent with radiological results and clinical symptoms, defined as changes in ventricle size and no clinical improvement. The mean pressure difference was 38.07±23.58 mmH 2 O. The mean frequency of CSF lumbar tapping was 1.44±1.01 times. Pressure difference greater than 35 mmH 2 O was shown in 2.35% of the normal VPS function group (2 of 85) whereas it was shown in 64.29% of the suspected VPS malfunction group (9 of 14). The difference was statistically significant ( p =0.000001). Among 10 patients with under-drainage, 5 patients underwent shunt revision. The causes of the shunt malfunction included 3 cases of proximal occlusion and 2 cases of distal obstruction and valve malfunction. Under-drainage of CSF should be suspected if CSF lumbar tapping

  4. Multiple Chaotic Central Pattern Generators with Learning for Legged Locomotion and Malfunction Compensation

    DEFF Research Database (Denmark)

    Ren, Guanjiao; Chen, Weihai; Dasgupta, Sakyasingha

    2015-01-01

    on a simulated annealing algorithm. In a normal situation, the CPGs synchronize and their dynamics are identical. With leg malfunction or disability, the CPGs lose synchronization leading to independent dynamics. In this case, the learning mechanism is applied to automatically adjust the remaining legs...... in a physical simulation of a quadruped as well as a hexapod robot and finally in a real six-legged walking machine called AMOSII. The experimental results presented here reveal that using multiple CPGs with learning is an effective approach for adaptive locomotion generation where, for instance, different body...... chaotic CPG controller has difficulties dealing with leg malfunction. Specifically, in the scenarios presented here, its movement permanently deviates from the desired trajectory. To address this problem, we extend the single chaotic CPG to multiple CPGs with learning. The learning mechanism is based...

  5. Vagal Nerve Stimulator Malfunction with Change in Neck Position: Case Report and Literature Review.

    Science.gov (United States)

    D'Agostino, Erin; Makler, Vyacheslav; Bauer, David F

    2018-06-01

    Vagal nerve stimulation is a safe and well-tolerated treatment for drug-resistant epilepsy. Complications and failure of the device can result from lead fracture, device malfunction, disconnection, or battery displacement and can result in a variety of symptoms. We present an interesting case of stimulator malfunction with increased impedance change seen only with a change in head position. The patient is a 25-year-old male with a vagal nerve stimulator (VNs) placed for medically refractory epilepsy who presented with neck pain and an electrical pulling sensation in his neck whenever he turned his head to the right. Initial interrogation of the VNs showed normal impedance. Subsequent interrogation with the patient's head turned found increased impedance only when the head was turned to the right. The patient had successful removal and replacement of the device with resolution of his preoperative complaints. Partial lead fracture was seen at explant. VNs malfunction can present in atypical ways. Positional maneuvers may help with its timely diagnosis. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. RIG-1 expression is associated with sexual malfunctions of female type 2 diabetic patients

    Directory of Open Access Journals (Sweden)

    Batool Hajebrahimi

    2017-03-01

    Full Text Available Introduction: The patients with type 2 diabetes (T2D suffer from the malfunctions of the sexual behaviors, and several mechanisms have been proposed to describe these disorders. The innate immunity may be involved in the malfunctions of T2D patients. Melanoma differentiation-associated protein 5 (MDA5 and retinoic acid (RA-inducible gene 1 (RIG-1, as the innate immunity receptors, are the responsible molecules for the activation of some intracellular signaling pathways and the induction of inflammation. Thus, this study aimed to examine the molecules which may participate in the induction/stimulation of sexual malfunctions in the female T2D patients. Methods: Sexual functions were evaluated in 41 female T2D patients using the Female Sexual Function Index (FSFI questionnaire. Real-time polymerase chain reaction (PCR technique was used to quantify MDA5 and RIG-1 mRNA levels. Results: Results showed that increased RIG-1 mRNA levels were significantly associated with the bad orgasm in the female T2D patients compared to the female patients with good orgasm. Expression of RIG-1 and MDA5 levels were not associated with other sexual functions’ criteria. Conclusion: The findings of this study demonstrated that bad orgasm is associated with the increased RIG-1 expression. Consequently, the correlation between inflammation and bad orgasm in a RIG-1 dependent manner is suggested.

  7. Increasing Mud Pump Motor Reliability against Malfunctions of DC Motor Excitation System

    Science.gov (United States)

    Nikulin, O. V.; Shabanov, V. A.

    2017-10-01

    The most widely used drilling machinery, such as mud pumps, draw-works, and rotors, use direct-current (DC) motors with independent excitation as the electric drive. Drilling machinery drives operate in harsh ambient conditions, including those with the presence of moisture, dust and vibration, which increases the malfunction rate of both drilling equipment and their electric drives. One of the frequently encountered malfunctions are DC motor excitation coil faults, which disrupt the normal functioning of electric drives, often leading to shutdown of the drilling process. In a four-pole DC motor, the malfunction of one coil leads to lack of excitation current in just one coil pair, while the other pair remains functional. In this case, DC motors and drilling equipment can remain operational, which would allow for continuing the drilling process. This paper considers the possibility of operation of a DC motor on a drilling rig in those cases when one pair of excitation coils is non-functional, and describes the device for switching between the excitation coils and the auxiliary winding in a DC motor with independent excitation.

  8. An Experimental Study of Emission and Combustion Characteristics of Marine Diesel Engine with Fuel Injector Malfunctions

    Directory of Open Access Journals (Sweden)

    Kowalski Jerzy

    2016-01-01

    Full Text Available The presented paper shows the results of the laboratory study on the relation between chosen malfunctions of a fuel injector and composition of exhaust gas from the marine engine. The object of research is a marine 3-cylinder, four-stroke, direct injection diesel engine with an intercooler system. The engine was loaded with a generator and supercharged. The generator was electrically connected to the water resistance. The engine operated with a load between 50 kW and 250 kW at a constant speed. The engine load and speed, parameters of the turbocharger, systems of cooling, fuelling, lubricating and air exchange, were measured. Fuel injection and combustion pressures in all cylinders of the engine were also recorded. Exhaust gas composition was recorded by using a electrochemical gas analyzer. Air pressure, temperature and humidity were also recorded. Emission characteristics of the engine were calculated according to ISO 8178 standard regulations. During the study the engine operated at the technical condition recognized as „working properly” and with simulated fuel injector malfunctions. Simulation of malfunctions consisted in the increasing and decreasing of fuel injector static opening pressure, decalibration of fuel injector holes and clogging 2 neighboring of 9 fuel injector holes on one of 3 engine cylinders.

  9. Development of expert system on personal computer for diagnosis of nuclear reactor malfunctions

    International Nuclear Information System (INIS)

    Kameyama, Takanori; Uekata, Tomomichi; Oka, Yoshiaki; Kondo, Shunsuke; Togo, Yasumasa

    1988-01-01

    An expert system on a personal computer has been developed for diagnosis of malfunction of the fast experimental reactor 'JOYO'. Prolog-KABA is used as the language. The system diagnoses the event which causes scram or set-back of the control rod after an alarm at steady state operation. The knowledge base (KB) consists of several sub-KBs and a meta-KB. Using the forward chaining, the meta-KB decides which sub-KB should be accessed. The cause of the malfunction is identified in the sub-KB using the backward chaining. The terms expressing the characteristics of the events are involved in the production rules as attributes in order to use the Prolog function of pattern matching and back-tracking for efficient inference. The total number of the rules in the system is about 400. The experiments using the plant simulator of 'JOYO' have shown that malfunctions are successfully identified by the diagnosis system. It takes about 10s for each diagnosis using the 16-bits personal computer, PC-9801 VM. (author)

  10. Intelligent Engine Systems Work Element 1.2: Malfunction and Operator Error Reduction

    Science.gov (United States)

    Wiseman, Matthew

    2005-01-01

    Jet engines, although highly reliable and safe, do experience malfunctions that cause flight delays, passenger stress, and in some cases, in conjunction with inappropriate crew response, contribute to airplane accidents. On rare occasions, the anomalous engine behavior is not recognized until it is too late for the pilots to do anything to prevent or mitigate the resulting engine malfunction causing in-flight shutdowns (IFSDs), aborted takeoffs (ATOs), or loss of thrust control (LOTC). In some cases, the crew response to a myriad of external stimuli and existing training procedures is the source of the problem mentioned above. The problem is the reduction of jet engine malfunctions (IFSDs, ATOs, and LOTC) and inappropriate crew response (PSM+ICR) through the use of evolving and advanced technologies. The solution is to develop the overall system health maintenance architecture, detection and accommodation technologies, processes, and enhanced crew interfaces that would enable a significant reduction in IFSDs, ATOs, and LOTC. This program defines requirements and proposes a preliminary design concept of an architecture that enables the realization of the solution.

  11. A Novel Technique for Laparoscopic Salvage of CAPD Catheter Malfunction and Migration: The Santosh-PGI Hanging Loop Technique

    Directory of Open Access Journals (Sweden)

    Santosh Kumar

    2015-01-01

    Full Text Available CAPD catheter malfunction is a common problem. Obstruction due to wrapping by appendices epiploicae of sigmoid colon has been rarely reported in literature. We report a case of CAPD catheter malfunction caused by catheter tip migration and obstruction by appendices epiploicae that was successfully managed by laparoscopic hanging loop technique. This case report highlights the ease with which epiplopexy can be performed and catheter tip migration can be prevented by this innovative laparoscopic procedure.

  12. Bioprinting for vascular and vascularized tissue biofabrication.

    Science.gov (United States)

    Datta, Pallab; Ayan, Bugra; Ozbolat, Ibrahim T

    2017-03-15

    Bioprinting is a promising technology to fabricate design-specific tissue constructs due to its ability to create complex, heterocellular structures with anatomical precision. Bioprinting enables the deposition of various biologics including growth factors, cells, genes, neo-tissues and extra-cellular matrix-like hydrogels. Benefits of bioprinting have started to make a mark in the fields of tissue engineering, regenerative medicine and pharmaceutics. Specifically, in the field of tissue engineering, the creation of vascularized tissue constructs has remained a principal challenge till date. However, given the myriad advantages over other biofabrication methods, it becomes organic to expect that bioprinting can provide a viable solution for the vascularization problem, and facilitate the clinical translation of tissue engineered constructs. This article provides a comprehensive account of bioprinting of vascular and vascularized tissue constructs. The review is structured as introducing the scope of bioprinting in tissue engineering applications, key vascular anatomical features and then a thorough coverage of 3D bioprinting using extrusion-, droplet- and laser-based bioprinting for fabrication of vascular tissue constructs. The review then provides the reader with the use of bioprinting for obtaining thick vascularized tissues using sacrificial bioink materials. Current challenges are discussed, a comparative evaluation of different bioprinting modalities is presented and future prospects are provided to the reader. Biofabrication of living tissues and organs at the clinically-relevant volumes vitally depends on the integration of vascular network. Despite the great progress in traditional biofabrication approaches, building perfusable hierarchical vascular network is a major challenge. Bioprinting is an emerging technology to fabricate design-specific tissue constructs due to its ability to create complex, heterocellular structures with anatomical precision

  13. CBDS: Constraint-based diagnostic system for malfunction identification in the nuclear power plant

    International Nuclear Information System (INIS)

    Ha, J.

    1992-01-01

    Traditional rule-based diagnostic expert systems use the experience of experts in the form of rules that associate symptoms with underlying faults. A commonly recognized failing of such systems is their narrow range of expertise and their inability to recognize problems outside this range of expertise. A model base diagnostic system isolating malfunctioning components-CBDS, the Constraint based Diagnostic System-has been developed. Since the intended behavior of a device is more predictable than unintended behaviors (faults), a model based system using the intended behavior has a potential to diagnose unexpected malfunctions by considering faults as open-quotes anything other than the intended behavior.close quotes As a knowledge base, the CBDS generates and decomposes a constraint network based on the structure and behavior model, which are represented symbolically in algebraic equations. Behaviors of generic components are organized in a component model library. Once the library is available, actual domain knowledge can be represented by declaring component types and their connections. To capture various plant knowledge, the mixed model was developed which allow the use of different parameter types in one equation by defining various operators. The CBDS uses the general idea of model based diagnosis. It detects a discrepancy between observation and prediction using constraint propagation, which carriers and accumulates the assumptions when parameter values are deduced. When measured plant parameters are asserted into a constraint network and are propagated through the network, a discrepancy will be detected if there exists any malfunctioning component. The CBDS was tested in the Recirculation Flow Control System of a BWR, and has been shown to be able to diagnose unexpected events

  14. Intermittent voiding per urethra as an indicator of cutaneous vesicostomy malfunction.

    Science.gov (United States)

    Hojjat, Asal; Kajbafzadeh, Abdol-Mohammad; Sina, Alireza; Mazaheri, Tina; Rad, Mona Vahidi; Nezami, Behtash Ghazi; Mohammadinejad, Payam

    2015-01-01

    To present a new approach for management of cutaneous vesicostomy (CV) prolapse, with special emphasis on normal appearing vesicostomy may be malfunctioning. To introduce the application of temporary stoma-free drainage as a diagnostic and therapeutic tool. From December 2000 to September 2006, 66 children (61 males and 5 females) with CV were studied. The mean age at vesicostomy was 7 months (range 1-30), and the main underlying disease was posterior urethral valves (in 45 children, 68%). Indications for CV included significant hydroureteronephrosis (HUN) and recurrent urinary tract infection. Patients were followed up for complications and were treated based on our institutional approach. All patients with persistent upper tract dilatation and micturition per urethra underwent temporary bladder (via stoma) free drainage. Patients with stomal stenosis were managed either by a revision surgery or by simple dilatation and intermittent catheterization. Purse string suturing was applied in mucosal prolapses as the first choice. The complications were observed in 21 patients (31%), including twelve stomal stenosis, nine severe mucosal prolapses, and two recurrent urinary infections. HUN and significant voiding per urethra persisted following initial CV in 19 out of 66 patients (29%), eleven of which having normal appearing CVs. Seventeen of these patients were managed by temporary stoma-free drainage (accompanied by purse string suturing in mucosal prolapse), and two patients with severe stenosis underwent surgical revision. Temporary stoma-free drainage improved HUN in 94% of patients (16 of 17). Voiding per urethra is an indicator of CV malfunction, and temporary stoma-free drainage can be a diagnostic and therapeutic option in such children. A seemingly open CV may still be malfunctioning, and ureterovesical or intravesical obstructions should be considered if HUN does not improve following temporary stoma-free drainage.

  15. Artificial urethral sphincters: Value of plain film radiography in evaluation of prosthesis malfunction

    International Nuclear Information System (INIS)

    Rose, S.C.; Hansen, M.E.; Webster, G.; Dunnick, N.R.

    1987-01-01

    Case records were reviewed to determine the diagnostic efficacy of plain radiographs in the evaluation of inflatable artificial urethral sphincters. Of 84 patients with prostheses, 21 (25%) developed complications. Fluid leaks were found in 16 patients who presented with recurrent incontinence; plain radiographs demonstrated an interval decrease in balloon reservoir diameter. Kinked tubing, which was evident on plain films, caused acute urinary retention in three patients. However, plain radiographs failed to detect evidence of prosthesis erosion into the urethra in either of two patients with this complication. Although urethroscopy is needed to detect urethral erosion, plain radiographs are inexpensive and reliable in the initial evaluation of artifical sphincter malfunction

  16. Human Errors - A Taxonomy for Describing Human Malfunction in Industrial Installations

    DEFF Research Database (Denmark)

    Rasmussen, Jens

    1982-01-01

    This paper describes the definition and the characteristics of human errors. Different types of human behavior are classified, and their relation to different error mechanisms are analyzed. The effect of conditioning factors related to affective, motivating aspects of the work situation as well...... as physiological factors are also taken into consideration. The taxonomy for event analysis, including human malfunction, is presented. Possibilities for the prediction of human error are discussed. The need for careful studies in actual work situations is expressed. Such studies could provide a better...

  17. Immune malfunction in the GPR39 zinc receptor of knockout mice

    DEFF Research Database (Denmark)

    Młyniec, Katarzyna; Trojan, Ewa; Ślusarczyk, Joanna

    2016-01-01

    Depression is a serious psychiatric disorder affecting not only the monaminergic, glutamatergic, and GABAergic neurosystems, but also the immune system. Patients suffering from depression show disturbance in the immune parameters as well as increased susceptibility to infections. Zinc is well known...... as an anti-inflammatory agent, and its link with depression has been proved, zinc deficiency causing depression- and anxiety-like behavior with immune malfunction. It has been discovered that trace-element zinc acts as a neurotransmitter in the central nervous system via zinc receptor GPR39. In this study we...

  18. Comparison of the PLCS malfunction event analyses by using the CESEC III and MEDUSA codes

    International Nuclear Information System (INIS)

    Oh, Myung Taek; Park, Chan Eok; Kim, Shin Whan; Seo, Jong Tae

    2004-01-01

    The MEDUSA is a code developed by Korea Power Engineering Company (KOPEC) for non-LOCA and LOCA analysis, providing two-fluid, three-field representation of two-phase flow. In this paper, as an effort to verify the MEDUSA code, comparative simulation for Pressurizer Level Control System (PLCS) malfunction with loss of off-site power is performed for UCN 3 and 4 plants. The results by the MEDUSA are compared with those calculated by the CESEC-III, a licensing analysis code used for Korean Standard Nuclear Power Plant (KSNP)

  19. Initial Clinical Experience Using the Amplatzer Vascular Plug

    International Nuclear Information System (INIS)

    Tuite, David J.; Kessel, David O.; Nicholson, Anthony A.; Patel, Jai V.; McPherson, Simon J.; Shaw, David R.

    2007-01-01

    Background and purpose. The Amplatzer Vascular Plug (AVP) is a self-expanding nitinol wire mesh vascular embolization device derived from the Amplatz septal occluder. We assessed the results of vascular embolization obtained using the AVP. Methods. A retrospective review was carried out of 23 consecutive cases of vascular embolization using the AVP in a variety of different clinical settings. The AVP was chosen to have a diameter approximately 30-50% greater than the target vessel. The device was delivered via an appropriately sized guide catheter and was released when satisfactorily positioned. Additional embolic agents were used in some cases. Results. All target vessels were successfully occluded with no device malpositioning or malfunction. In 14 (61%) patients the AVP was the sole embolic material. In the remaining patients additional agents were used, particularly in preoperative embolization of highly vascular renal tumors. The AVP does not cause instantaneous thrombosis and in high-flow situations thrombosis typically takes up to 15 min. Conclusion. The AVP is a safe, effective embolization device that provides a useful adjunct to the therapeutic armamentarium. It is particularly suited to the treatment of short high-flow vessels where coil migration and catheter dislodgment might occur. In the majority of cases no additional embolic agents are necessary but it may take up to 15 min for complete thrombosis to occur

  20. Combination of sealed source and radiotracer technique to understand malfunctioning in a chemical plant

    Energy Technology Data Exchange (ETDEWEB)

    Yelgaonkar, V.N. [Quality Assurance and Isotope Applications Services, BRIT, Vashi Complex, Navi Mumbai 400705 (India)], E-mail: vivekyel@rediffmail.com; Jayakumar, T.K.; Singh, Sudhir; Sharma, M.K. [Quality Assurance and Isotope Applications Services, BRIT, Vashi Complex, Navi Mumbai 400705 (India)

    2009-07-15

    Pure terphthalic acid (PTA) is produced by the oxidation of paraxylene in an oxidation reactor of a PTA plant. Since the reaction is exothermic, the temperature rises above 210 deg. C. Vapours formed in the reactor are passed through a series of heat exchangers and the cooled liquid is fed back to the reactor, which flows to the reactor by gravity. In one of the heat exchangers, improper flow distribution in the inlet and outlet pipelines was suspected. Maldistribution of flow in the heat exchanger was also suspected. Gamma scanning of the pipelines and a radiotracer experiment were carried out in the heat exchanger to study the malfunctioning. A specially fabricated pipe scanner was used to scan both 24 in diameter and 16 in diameter pipelines. From gamma scanning of the pipelines mostly on the bends, absence of the full bore flow of the liquid was observed. Presence of vapours along with the liquid could be obstructing the liquid flow, thereby causing the malfunctioning. A radiotracer experiment was also carried out to study the flow pattern in the heat exchanger. From the experiment, mean residence time of the heat exchanger was estimated as 470 s, which theoretically should be about 102 s. It indicated that the flow is decelerated in the heat exchanger because of the presence of vapour lock in the tube side.

  1. Utilization of an Airborne Plant Chlorophyll Imaging System for Detection of Septic System Malfunction

    Science.gov (United States)

    Spiering, Bruce A.; Carter, Gregory A.

    2001-01-01

    Malfunctioning, or leaking, sewer systems increase the supply of water and nutrients to surface vegetation. Excess nutrients and harmful bacteria in the effluent pollute ground water and local water bodies and are dangerous to humans and the aquatic ecosystems. An airborne multispectral plant chlorophyll imaging system (PCIS) was used to identify growth patterns in the vegetation covering onsite and public sewer systems. The objective was to evaluate overall performance of the PCIS as well as to determine the best operational configuration for this application. The imaging system was flown in a light aircraft over selected locations Mobile County, Alabama. Calibration panels were used to help characterize instrument performance. Results demonstrated that the PCIS performed well and was capable of detecting septic leakage patterns from altitudes as high as 915 m. From 915 m, 6 of 18 sites were suspected to have sewage leakage. Subsequent ground inspections confirmed leakage on 3 of the 6 sites. From 610 m, 3 of 8 known leakage sites were detected. Tree cover and shadows near residential structures prevented detection of several known malfunctioning systems. Also some leakages known to occur in clear areas were not detected. False detections occurred in areas characterized by surface water drainage problems or recent excavation.

  2. An enhanced data visualization method for diesel engine malfunction classification using multi-sensor signals.

    Science.gov (United States)

    Li, Yiqing; Wang, Yu; Zi, Yanyang; Zhang, Mingquan

    2015-10-21

    The various multi-sensor signal features from a diesel engine constitute a complex high-dimensional dataset. The non-linear dimensionality reduction method, t-distributed stochastic neighbor embedding (t-SNE), provides an effective way to implement data visualization for complex high-dimensional data. However, irrelevant features can deteriorate the performance of data visualization, and thus, should be eliminated a priori. This paper proposes a feature subset score based t-SNE (FSS-t-SNE) data visualization method to deal with the high-dimensional data that are collected from multi-sensor signals. In this method, the optimal feature subset is constructed by a feature subset score criterion. Then the high-dimensional data are visualized in 2-dimension space. According to the UCI dataset test, FSS-t-SNE can effectively improve the classification accuracy. An experiment was performed with a large power marine diesel engine to validate the proposed method for diesel engine malfunction classification. Multi-sensor signals were collected by a cylinder vibration sensor and a cylinder pressure sensor. Compared with other conventional data visualization methods, the proposed method shows good visualization performance and high classification accuracy in multi-malfunction classification of a diesel engine.

  3. Publisher Correction

    DEFF Research Database (Denmark)

    Turcot, Valérie; Lu, Yingchang; Highland, Heather M

    2018-01-01

    In the published version of this paper, the name of author Emanuele Di Angelantonio was misspelled. This error has now been corrected in the HTML and PDF versions of the article.......In the published version of this paper, the name of author Emanuele Di Angelantonio was misspelled. This error has now been corrected in the HTML and PDF versions of the article....

  4. Author Correction

    DEFF Research Database (Denmark)

    Grundle, D S; Löscher, C R; Krahmann, G

    2018-01-01

    A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.......A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper....

  5. Andrographolide Attenuates LPS-Induced Cardiac Malfunctions Through Inhibition of IκB Phosphorylation and Apoptosis in Mice

    Directory of Open Access Journals (Sweden)

    Jinlong Zhang

    2015-11-01

    Full Text Available Background/Aims: Cardiac malfunction is a common complication in sepsis and significantly increases the mortality of patients in septic shock. However, no studies have examined whether andrographolide (And reduces LPS-induced myocardial malfunction. Methods: Left ventricular systolic and diastolic functions were examined using echocardiography. TNF-a and IL-1ß protein levels were detected by an enzyme-linked immunosorbent assay (ELISA. NO oxidation products were determined using Griess reagent. Protein expression levels of inhibitors of NF-κBa (IκB and phospho-IκB were determined via Western blot. Oxidative injury was determined by measuring myocardial lipid peroxidation and superoxide dismutase activity. Cardiac apoptosis was examined by terminal deoxynucleotidyl transferase-mediated dUTP nickend-labeling (TUNEL and cardiac caspase 3/7 activity. Results: And blunted LPS-induced myocardial malfunctions in mice. LPS induced TNF-a, IL-1ß, and NO production as well as I-κB phosphorylation. Cardiac apoptosis was attenuated via incubation with And, but the extent of oxidative injury remained unaffected. Conclusion: And prevents LPS-induced cardiac malfunctions in mice by inhibiting TNF-a, IL-1ß, and NO production, IκB phosphorylation, and cardiac apoptosis, indicating that And may be a potential agent for preventing myocardial malfunction during sepsis.

  6. Simulation of rectifier voltage malfunction on OWECS, four-level converter, HVDC light link: Smart grid context tool

    International Nuclear Information System (INIS)

    Seixas, M.; Melício, R.; Mendes, V.M.F.

    2015-01-01

    Highlights: • Floating offshore wind turbine in deep water. • DC link and voltage malfunction. • Converter topology considered is four-level. • Controllers are based on fractional-order. • Smart grid context. - Abstract: This paper presents a model for the simulation of an offshore wind system having a rectifier input voltage malfunction at one phase. The offshore wind system model comprises a variable-speed wind turbine supported on a floating platform, equipped with a permanent magnet synchronous generator using full-power four-level neutral point clamped converter. The link from the offshore floating platform to the onshore electrical grid is done through a light high voltage direct current submarine cable. The drive train is modeled by a three-mass model. Considerations about the smart grid context are offered for the use of the model in such a context. The rectifier voltage malfunction domino effect is presented as a case study to show capabilities of the model

  7. Battery Malfunction of a Leadless Cardiac Pacemaker - A Worrisome Single-Center Experience.

    Science.gov (United States)

    Richter, Sergio; Döring, Michael; Ebert, Micaela; Bode, Kerstin; Müssigbrodt, Andreas; Sommer, Philipp; Husser, Daniela; Hindricks, Gerhard

    2018-03-14

    Leadless cardiac pacemaker (LCP) therapy has been established clinically as a feasible and safe alternative to conventional transvenous pacemaker therapy for patients with an indication for single-chamber right-ventricular pacing. 1-3 However, reports on loss of telemetry and pacing output due to abrupt battery failure called the safety of one of the two commercially available systems seriously into question. The initial battery advisory with the Nanostim™ LCP was issued by the manufacturer in October 2016, who instantly called a global stop to Nanostim™ implants. To this day, similar battery issues have not been described for the Micra™ transcatheter pacing system. Therefore, we thought to analyze the long-term pacemaker performance and rate of battery malfunction of the Nanostim™ LCP in our patient population.

  8. Overexposure of patients due to malfunctions or defects in radiation equipment

    International Nuclear Information System (INIS)

    Gill, J.R.

    1992-01-01

    Some 38 incidents involving patient overexposure due to malfunctions or defects in radiation equipment were notified to HSE between 1986 and 1990. Of these cases, 30 involved diagnostic X ray equipment, while the remainder involved nuclear medicine or radiotherapy equipment. Those cases involving X ray equipment are examined in detail and grouped into six categories. The numbers of patients affected varied. In one case an estimated 350 patients were affected: in another, 240; while 13 cases affected only a single patient. A very rough estimate of the collective effective dose equivalent in the 30 cases comes to 5 man sieverts. It is concluded that improvements are needed in fault finding procedures, and guidance is needed on consistent methods of dose estimation and reporting. Improvements for the longer term include the selection of reliable components during manufacture; application of HSE guidance in software design for programmable electronic systems; and equipment design to incorporate fault detection and inhibition of operation to prevent excessive exposures

  9. Early Events in Retinal Degeneration Caused by Rhodopsin Mutation or Pigment Epithelium Malfunction: Differences and Similarities

    Science.gov (United States)

    Di Pierdomenico, Johnny; García-Ayuso, Diego; Pinilla, Isabel; Cuenca, Nicolás; Vidal-Sanz, Manuel; Agudo-Barriuso, Marta; Villegas-Pérez, María P.

    2017-01-01

    To study the course of photoreceptor cell death and macro and microglial reactivity in two rat models of retinal degeneration with different etiologies. Retinas from P23H-1 (rhodopsin mutation) and Royal College of Surgeon (RCS, pigment epithelium malfunction) rats and age-matched control animals (Sprague-Dawley and Pievald Viro Glaxo, respectively) were cross-sectioned at different postnatal ages (from P10 to P60) and rhodopsin, L/M- and S-opsin, ionized calcium-binding adapter molecule 1 (Iba1), glial fibrillary acid protein (GFAP), and proliferating cell nuclear antigen (PCNA) proteins were immunodetected. Photoreceptor nuclei rows and microglial cells in the different retinal layers were quantified. Photoreceptor degeneration starts earlier and progresses quicker in P23H-1 than in RCS rats. In both models, microglial cell activation occurs simultaneously with the initiation of photoreceptor death while GFAP over-expression starts later. As degeneration progresses, the numbers of microglial cells increase in the retina, but decreasing in the inner retina and increasing in the outer retina, more markedly in RCS rats. Interestingly, and in contrast with healthy animals, microglial cells reach the outer nuclei and outer segment layers. The higher number of microglial cells in dystrophic retinas cannot be fully accounted by intraretinal migration and PCNA immunodetection revealed microglial proliferation in both models but more importantly in RCS rats. The etiology of retinal degeneration determines the initiation and pattern of photoreceptor cell death and simultaneously there is microglial activation and migration, while the macroglial response is delayed. The actions of microglial cells in the degeneration cannot be explained only in the basis of photoreceptor death because they participate more actively in the RCS model. Thus, the retinal degeneration caused by pigment epithelium malfunction is more inflammatory and would probably respond better to interventions

  10. Aging and malfunction of valves in CANDU special safety systems. Phase 1

    International Nuclear Information System (INIS)

    1989-03-01

    Aging and wear related valve malfunctions have been reported in American nuclear generating systems. This report documents the first attempt to study these phenomena on a global basis in Canadian nuclear power plants. A general methodology outlines an approach to this type of study which is amenable to use within existing information structures. Nuclear regulatory requirements which influence the testing of valves in Canadian nuclear power plants are reviewed. The reporting systems which emanate from these requirements are discussed and sources of valve failure data are reviewed. It is determined that modifications to existing failure reporting systems are required before practical means of collecting data necessary for the analysis of age related valve malfunctions can be developed. In spite of limitations in reported failure data, a partial data base is compiled for valve failures in Special Safety Systems of domestic nuclear plants. Data are reported for the period 1982 to 1986. The valve population and basic parameters of each valve such as type, operator, function, etc., and the reported failures against this population are compiled and reviewed for evidence of time dependent versus random failure trends. Results suggest that there is no clear age related failure trend. In fact, some systems and stations, experienced a reduction in failure rates with years of servicing, suggesting that some earlier generic valve problems may have been solved. Present inspection, test, and maintenance practices are reviewed and their effectiveness for purposes of predicting or preventing incipient failures is assessed to be of moderate value. Modern failure prevention methods are highlighted and their applicability discussed

  11. When do the symptoms of autonomic nervous system malfunction appear in patients with Parkinson's disease?

    Science.gov (United States)

    De Luka, Silvio R; Svetel, Marina; Pekmezović, Tatjana; Milovanović, Branislav; Kostić, Vladimir S

    2014-04-01

    Dysautonomia appears in almost all patients with Parkinson's disease (PD) in a certain stage of their condition. The aim of our study was to detect the development and type of autonomic disorders, find out the factors affecting their manifestation by analyzing the potential association with demographic variables related to clinical presentation, as well as the symptoms of the disease in a PD patient cohort. The patients with PD treated at the Clinic of Neurology in Belgrade during a 2-year period, divided into 3 groups were studied: 25 de novo patients, 25 patients already treated and had no long-term levodopa therapy-related complications and 22 patients treated with levodopa who manifested levodopa-induced motor complications. Simultaneously, 35 healthy control subjects, matched by age and sex, were also analyzed. Autonomic nervous system malfunction was defined by Ewing diagnostic criteria. The tests, indicators of sympathetic and parasympathetic nervous systems, were significantly different in the PD patients as compared with the controls, suggesting the failure of both systems. However, it was shown, in the selected groups of patients, that the malfunction of both systems was present in two treated groups of PD patients, while de novo group manifested only sympathetic dysfunction. For this reason, the complete autonomic neuropathy was diagnosed only in the treated PD patients, while de novo patients were defined as those with the isolated sympathetic dysfunction. The patients with the complete autonomic neuropathy differed from the subjects without such neuropathy in higher cumulative and motor unified Parkinson's disease rating score (UPDRS) (p nervous system disturbances among PD patients from the near onset of disease, with a predominant sympathetic nervous system involvement. The patients who developed complete autonomic neuropathy (both sympathetic and parasympathetic) were individuals with considerable level of functional failure, more severe clinical

  12. Malfunction diagnosis and applications of stable adaptive schemes for a nuclear reactor system

    International Nuclear Information System (INIS)

    Fukuda, Toshio; Shibata, Heki.

    1979-01-01

    Malfunction diagnosis concerns a method to detect the abnormal phenomena during nuclear reactor operations, while stable adaptive schemes does the application of Model Reference Adaptive System (MRAS) to the nonlinear dynamics of a reactor for parameter identification and control. The new method for the malfunction diagnosis consists of the following ideas; an index defined as the sum of ratios of the square of a factor score to the contribution weight of the factor, which is evaluated by applying the multi-factor analysis technique to the data of the state of nuclear reactor systems like neutron flux, temperature, flow rate and so on. The excess of the index over some given threshold shows the reactor system would be in an abnormal state. Then a theory of optimal filtering by Kalman with the aid of the stochastic approximation is applied to estimate the neutron flux distribution at its abnormal state and subsequently the squared sum of difference between desirable and estimated flux distributions shows the spot at which the abnormal phenomena would have occurred in terms of the peak of its distribution. Parameter identification and adaptive control schemes are presented for a point reactor and a loosely-coupled-core reactor with internal feedbacks which lead to the nonlinearity of the overall system. Both schemes are shown stable with new representations of the systems, which correspond to the nonminimal system representation, in the vein of the MRAS via the Lyapunov's method. For the sake of the parameter identification, model parameters can be adjusted adaptively as soon as measurements start, while plant parameters can also adaptively be compensated through control input to reduce the output error between the model and the plant for the case of the adaptive control. Some experiments of parameter identification for the thermal-hydraulic system are carried out successfully using a simplified channel in which flow rate is varied in a binary form. (J.P.N.)

  13. Shunt malfunction causing acute neurological deterioration in 2 patients with previously asymptomatic Chiari malformation Type I. Report of two cases.

    Science.gov (United States)

    Elliott, Robert; Kalhorn, Stephen; Pacione, Donato; Weiner, Howard; Wisoff, Jeffrey; Harter, David

    2009-08-01

    Patients with symptomatic Chiari malformation Type I (CM-I) typically exhibit a chronic, slowly progressive disease course with evolution of symptoms. However, some authors have reported acute neurological deterioration in the setting of CM-I and acquired Chiari malformations. Although brainstem dysfunction has been documented in patients with CM-II and hydrocephalus or shunt malfunction, to the authors' knowledge only 1 report describing ventriculoperitoneal (VP) shunt malfunction causing neurological deterioration in a patient with CM-I exists. The authors report on their experience with the treatment of previously asymptomatic CM-I in 2 children who experienced quite different manifestations of acute neurological deterioration secondary to VP shunt malfunction. Presumably, VP shunt malfunction created a positive rostral pressure gradient across a stenotic foramen magnum, resulting in tetraparesis from foramen magnum syndrome in 1 patient and acute ataxia and cranial nerve deficits from syringobulbia in the other. Although urgent shunt revisions yielded partial recovery of neurological function in both patients, marked improvement occurred only after posterior fossa decompression.

  14. Using Noninvasive Brain Measurement to Explore the Psychological Effects of Computer Malfunctions on Users during Human-Computer Interactions

    Directory of Open Access Journals (Sweden)

    Leanne M. Hirshfield

    2014-01-01

    Full Text Available In today’s technologically driven world, there is a need to better understand the ways that common computer malfunctions affect computer users. These malfunctions may have measurable influences on computer user’s cognitive, emotional, and behavioral responses. An experiment was conducted where participants conducted a series of web search tasks while wearing functional near-infrared spectroscopy (fNIRS and galvanic skin response sensors. Two computer malfunctions were introduced during the sessions which had the potential to influence correlates of user trust and suspicion. Surveys were given after each session to measure user’s perceived emotional state, cognitive load, and perceived trust. Results suggest that fNIRS can be used to measure the different cognitive and emotional responses associated with computer malfunctions. These cognitive and emotional changes were correlated with users’ self-report levels of suspicion and trust, and they in turn suggest future work that further explores the capability of fNIRS for the measurement of user experience during human-computer interactions.

  15. Publisher Correction

    DEFF Research Database (Denmark)

    Stokholm, Jakob; Blaser, Martin J.; Thorsen, Jonathan

    2018-01-01

    The originally published version of this Article contained an incorrect version of Figure 3 that was introduced following peer review and inadvertently not corrected during the production process. Both versions contain the same set of abundance data, but the incorrect version has the children...

  16. Publisher Correction

    DEFF Research Database (Denmark)

    Flachsbart, Friederike; Dose, Janina; Gentschew, Liljana

    2018-01-01

    The original version of this Article contained an error in the spelling of the author Robert Häsler, which was incorrectly given as Robert Häesler. This has now been corrected in both the PDF and HTML versions of the Article....

  17. Correction to

    DEFF Research Database (Denmark)

    Roehle, Robert; Wieske, Viktoria; Schuetz, Georg M

    2018-01-01

    The original version of this article, published on 19 March 2018, unfortunately contained a mistake. The following correction has therefore been made in the original: The names of the authors Philipp A. Kaufmann, Ronny Ralf Buechel and Bernhard A. Herzog were presented incorrectly....

  18. Influences of maternal nutritional status on vascular function in the offspring.

    Science.gov (United States)

    Poston, Lucilla

    2007-08-01

    Fetal growth restriction leading to low birthweight is associated with increased risk of ischaemic heart disease and hypertension in later life. Increasingly, it is recognised that cardiovascular risk may also be initiated in early life when the fetus and neonate are exposed to maternal nutritional excess. This review summarises the studies in man and animals that have investigated the potential role of vascular disorders in the aetiology of atherosclerosis and hypertension arising from early life nutritional deprivation or excess. Malfunction of the arterial endothelial cell layer in the offspring has been frequently described in association with both maternal under and overnutritional states and may play a permissive role in the origin of these disorders. Also prevalent is evidence for increased stiffness of the large arteries which may contribute to systolic hypertension. Further investigation is required into the intriguing suggestion that early life nutritional imbalance may adversely influence vascular angiogenesis leading to rarefaction and increased peripheral vascular resistance.

  19. Vascular grading of angiogenesis

    DEFF Research Database (Denmark)

    Hansen, S; Grabau, D A; Sørensen, Flemming Brandt

    2000-01-01

    The study aimed to evaluate the prognostic value of angiogenesis by vascular grading of primary breast tumours, and to evaluate the prognostic impact of adding the vascular grade to the Nottingham Prognostic Index (NPI). The investigation included 836 patients. The median follow-up time was 11...... years and 4 months. The microvessels were immunohistochemically stained by antibodies against CD34. Angiogenesis was graded semiquantitatively by subjective scoring into three groups according to the expected number of microvessels in the most vascular tumour area. The vascular grading between observers...... for 24% of the patients, who had a shift in prognostic group, as compared to NPI, and implied a better prognostic dissemination. We concluded that the angiogenesis determined by vascular grading has independent prognostic value of clinical relevance for patients with breast cancer....

  20. Vascular grading of angiogenesis

    DEFF Research Database (Denmark)

    Hansen, S; Grabau, D A; Sørensen, Flemming Brandt

    2000-01-01

    The study aimed to evaluate the prognostic value of angiogenesis by vascular grading of primary breast tumours, and to evaluate the prognostic impact of adding the vascular grade to the Nottingham Prognostic Index (NPI). The investigation included 836 patients. The median follow-up time was 11...... years and 4 months. The microvessels were immunohistochemically stained by antibodies against CD34. Angiogenesis was graded semiquantitatively by subjective scoring into three groups according to the expected number of microvessels in the most vascular tumour area. The vascular grading between observers...... impact for 24% of the patients, who had a shift in prognostic group, as compared to NPI, and implied a better prognostic dissemination. We concluded that the angiogenesis determined by vascular grading has independent prognostic value of clinical relevance for patients with breast cancer....

  1. Corrective Jaw Surgery

    Medline Plus

    Full Text Available ... out more. Corrective Jaw Surgery Corrective Jaw Surgery Orthognathic surgery is performed to correct the misalignment of jaws ... out more. Corrective Jaw Surgery Corrective Jaw Surgery Orthognathic surgery is performed to correct the misalignment of jaws ...

  2. Imaging and therapeutic approach of hemangiomas and vascular malformations in the pediatric age group

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, J; Garel, L [Dept. of Medical Imaging, Hopital Sainte-Justine, Montreal, QB (Canada)

    1999-12-01

    Terminology regarding the vascular lesions of the soft tissues remains confusing. A single classification is necessary in order to decide on the proper investigation and the best treatment. At the Workshop on Vascular Anomalies in Rome in June 1996, the membership accepted the Mulliken and Glowacki classification, which differentiates vascular lesions into vascular tumors, including hemangiomas and vascular malformations. At Sainte-Justine, we have set up a multidisciplinary clinic for the discussion of problem patients with vascular anomalies, both in terms of diagnosis and treatment. In this review, we present our experience regarding the classification, the imaging modalities and the treatment of vascular anomalies. In our experience, Doppler ultrasound should be the initial imaging modality for recognizing vascular tumors from vascular malformations. CT scan or magnetic resonance imaging is best to evaluate the extent of the lesions prior to treatment. A multidisciplinary approach is essential to establish a correct diagnosis and define accordingly the appropriate treatment and follow-up. (orig.)

  3. Impulse control disorder, lysosomal malfunction and ATP13A2 insufficiency in Parkinsonism.

    Science.gov (United States)

    Liu, Jun-Ping; Li, Jianfeng; Lu, Yanhua; Wang, Lihui; Chen, Gang

    2017-02-01

    Lysosomal transport of cargos in neurons is essential for neuronal proteostasis, transmission and functional motors and behaviours. Lysosomal malfunction including storage disorders is involved in the pathogenesis of Parkinson's disease (PD). Given the unclear molecular mechanisms of diverse defects in PD phenotypes, especially behavioural deficits, this mini review explores the cellular contexts of PD impulse control disorders and the molecular aspects of lysosomal cross-membrane transports. Focuses are paid to trace metal involvements in α-synuclein assembly in Lewy bodies, the functions and molecular interactions of ATP13A2 as ATPase transporters in lysosomal membranes for cross-membrane trafficking and lysosomal homeostasis, and our current understandings of the neural circuits in ICD. Erroneously polarized distributions of cargos such as metals and lipids on each side of lysosomal membranes triggered by gene mutations and deregulated expression of ATP13A2 may thus instigate sensing protein structural changes such as aggregations, organelle degeneration, and specific neuronal ageing and death in Parkinsonism. © 2016 John Wiley & Sons Australia, Ltd.

  4. Ares-I-X Vehicle Preliminary Range Safety Malfunction Turn Analysis

    Science.gov (United States)

    Beaty, James R.; Starr, Brett R.; Gowan, John W., Jr.

    2008-01-01

    Ares-I-X is the designation given to the flight test version of the Ares-I rocket (also known as the Crew Launch Vehicle - CLV) being developed by NASA. As part of the preliminary flight plan approval process for the test vehicle, a range safety malfunction turn analysis was performed to support the launch area risk assessment and vehicle destruct criteria development processes. Several vehicle failure scenarios were identified which could cause the vehicle trajectory to deviate from its normal flight path, and the effects of these failures were evaluated with an Ares-I-X 6 degrees-of-freedom (6-DOF) digital simulation, using the Program to Optimize Simulated Trajectories Version 2 (POST2) simulation framework. The Ares-I-X simulation analysis provides output files containing vehicle state information, which are used by other risk assessment and vehicle debris trajectory simulation tools to determine the risk to personnel and facilities in the vicinity of the launch area at Kennedy Space Center (KSC), and to develop the vehicle destruct criteria used by the flight test range safety officer. The simulation analysis approach used for this study is described, including descriptions of the failure modes which were considered and the underlying assumptions and ground rules of the study, and preliminary results are presented, determined by analysis of the trajectory deviation of the failure cases, compared with the expected vehicle trajectory.

  5. Uncovering the link between malfunctions in Drosophila neuroblast asymmetric cell division and tumorigenesis

    Directory of Open Access Journals (Sweden)

    Kelsom Corey

    2012-11-01

    Full Text Available Abstract Asymmetric cell division is a developmental process utilized by several organisms. On the most basic level, an asymmetric division produces two daughter cells, each possessing a different identity or fate. Drosophila melanogaster progenitor cells, referred to as neuroblasts, undergo asymmetric division to produce a daughter neuroblast and another cell known as a ganglion mother cell (GMC. There are several features of asymmetric division in Drosophila that make it a very complex process, and these aspects will be discussed at length. The cell fate determinants that play a role in specifying daughter cell fate, as well as the mechanisms behind setting up cortical polarity within neuroblasts, have proved to be essential to ensuring that neurogenesis occurs properly. The role that mitotic spindle orientation plays in coordinating asymmetric division, as well as how cell cycle regulators influence asymmetric division machinery, will also be addressed. Most significantly, malfunctions during asymmetric cell division have shown to be causally linked with neoplastic growth and tumor formation. Therefore, it is imperative that the developmental repercussions as a result of asymmetric cell division gone awry be understood.

  6. Vascular Access in Children

    International Nuclear Information System (INIS)

    Krishnamurthy, Ganesh; Keller, Marc S.

    2011-01-01

    Establishment of stable vascular access is one of the essential and most challenging procedures in a pediatric hospital. Many clinical specialties provide vascular service in a pediatric hospital. At the top of the “expert procedural pyramid” is the pediatric interventional radiologist, who is best suited and trained to deliver this service. Growing awareness regarding the safety and high success rate of vascular access using image guidance has led to increased demand from clinicians to provide around-the-clock vascular access service by pediatric interventional radiologists. Hence, the success of a vascular access program, with the pediatric interventional radiologist as the key provider, is challenging, and a coordinated multidisciplinary team effort is essential for success. However, there are few dedicated pediatric interventional radiologists across the globe, and also only a couple of training programs exist for pediatric interventions. This article gives an overview of the technical aspects of pediatric vascular access and provides useful tips for obtaining vascular access in children safely and successfully using image guidance.

  7. Pediatric vascular access

    International Nuclear Information System (INIS)

    Donaldson, James S.

    2006-01-01

    Pediatric interventional radiologists are ideally suited to provide vascular access services to children because of inherent safety advantages and higher success from using image-guided techniques. The performance of vascular access procedures has become routine at many adult interventional radiology practices, but this service is not as widely developed at pediatric institutions. Although interventional radiologists at some children's hospitals offer full-service vascular access, there is little or none at others. Developing and maintaining a pediatric vascular access service is a challenge. Interventionalists skilled in performing such procedures are limited at pediatric institutions, and institutional support from clerical staff, nursing staff, and technologists might not be sufficiently available to fulfill the needs of such a service. There must also be a strong commitment by all members of the team to support such a demanding service. There is a slippery slope of expected services that becomes steeper and steeper as the vascular access service grows. This review is intended primarily as general education for pediatric radiologists learning vascular access techniques. Additionally, the pediatric or adult interventional radiologist seeking to expand services might find helpful tips. The article also provides education for the diagnostic radiologist who routinely interprets radiographs containing vascular access devices. (orig.)

  8. Vascular malformations in pediatrics

    International Nuclear Information System (INIS)

    Reith, W.; Shamdeen, M.G.

    2003-01-01

    Vascular malformations are the cause of nearly all non-traumatic intracranial hemorrhage in children beyond the neonatal stage. Therefore, any child presenting with spontaneous intracranial hemorrhage should be evaluated for child abuse and for vascular malformations. Intracerebral malformations of the cerebral vasculature include vein of Galen malformations, arteriovenous malformation (AVM), cavernomas, dural arteriovenous fistulas, venous anomalies (DVA), and capillary teleangiectasies. Although a few familial vascular malformation have been reported, the majority are sporadic. Clinical symptoms, diagnostic and therapeutic options are discussed. (orig.) [de

  9. Electroweak corrections

    International Nuclear Information System (INIS)

    Beenakker, W.J.P.

    1989-01-01

    The prospect of high accuracy measurements investigating the weak interactions, which are expected to take place at the electron-positron storage ring LEP at CERN and the linear collider SCL at SLAC, offers the possibility to study also the weak quantum effects. In order to distinguish if the measured weak quantum effects lie within the margins set by the standard model and those bearing traces of new physics one had to go beyond the lowest order and also include electroweak radiative corrections (EWRC) in theoretical calculations. These higher-order corrections also can offer the possibility of getting information about two particles present in the Glashow-Salam-Weinberg model (GSW), but not discovered up till now, the top quark and the Higgs boson. In ch. 2 the GSW standard model of electroweak interactions is described. In ch. 3 some special techniques are described for determination of integrals which are responsible for numerical instabilities caused by large canceling terms encountered in the calculation of EWRC effects, and methods necessary to get hold of the extensive algebra typical for EWRC. In ch. 4 various aspects related to EWRC effects are discussed, in particular the dependence of the unknown model parameters which are the masses of the top quark and the Higgs boson. The processes which are discussed are production of heavy fermions from electron-positron annihilation and those of the fermionic decay of the Z gauge boson. (H.W.). 106 refs.; 30 figs.; 6 tabs.; schemes

  10. Vascular dementia: Facts and controversies

    Directory of Open Access Journals (Sweden)

    Pavlović Aleksandra

    2013-01-01

    Full Text Available Vascular dementia (VaD is the second most frequent dementia after Alzheimer’s disease, and is diagnosed during lifetime in 20% of demented patients. Five­year survival rate in VaD is 39%, while it is estimated to be 75% in healthy persons of the same age. It is therefore important to make correct diagnosis of VaD early in the course of the disease. Risk factors for VaD are identical to stroke risk factors, and there are significant possibilities for the prevention of vascular cognitive decline. Cognitive decline develops acutely or step­by­step within three months after stroke, but more gradual progression of intellectual decline is also possible. Neurological examination can reveal pyramidal and extrapyramidal signs, pseudobulbar palsy, gait disturbance and urinary incontinence. Neuropsychological profile comprises the loss of cognitive set shifting, decline in word fluency, verbal learning difficulties, perseverations, difficulties in complex figure copying, and in patients with cortically located lesions also problems with speech and praxia. The basis of the diagnosis is, besides history, neurological examination and neuropsychological assessment, computed tomography and/ or magnetic resonance brain imaging. Vascular risk factors control is the most important measure in VaD prevention. Modern guidelines for the treatment of cognitive decline in VaD emphasize that donepezil can be useful in the improvement of cognitive status at the level of Class IIa recommendation at the level of evidence A, while memantine may be useful in patients with mixed VaD and Alzheimer’s disease dementia. [Projekat Ministarstva nauke Republike Srbije, br. 175022 i br. 175033

  11. Radiotherapy and risk of implantable cardioverter-defibrillator malfunctions: experimental data from direct exposure at increasing doses.

    Science.gov (United States)

    Zecchin, Massimo; Artico, Jessica; Morea, Gaetano; Severgnini, Mara; Bianco, Elisabetta; De Luca, Antonio; Fantasia, Anna Zorzin; Salvatore, Luca; Milan, Vittorino; Lucarelli, Matteo; Dissegna, Roberta; Cannatà, Antonio; Sinagra, Gianfranco

    2018-04-01

    During radiotherapy, in patients with implantable cardioverter-defibrillators (ICDs) malfunctions are considered more likely if doses more than 2 Gy reach the ICD site; however, most malfunctions occur with high-energy (>10 MV) radiations, and the risk is less defined using 6-MV linear accelerators. The purpose of the study is to experimentally evaluate the occurrence of malfunctions in ICDs radiated with a 6-MV linear accelerator at increasing photon doses. Thirty-two ICDs from all manufacturers (31 explanted and one demo) were evaluated; all devices with a sufficient battery charge underwent multiple radiations with a 6-MV photon beam reaching a cumulative dose at ICD site of 0.5, 1, 2, 3, 5 and 10 Gy and interrogated after every session. All antitachycardia therapies were left enabled; two ICDs were connected to a rhythm simulator (one simulating a complete atrioventricular block without ventricular activity) and visually monitored by external ECG and the ICD programmer during radiation. Thirteen ICDs were excluded before radiation because of battery depletion; after radiation up to the cumulative dose at the cardiac implantable electronic device site of 10 Gy, in the remaining 19 devices, programmation and battery charge remained unchanged and no switch to safety mode was observed; oversensing, pacing inhibition or inappropriate antitachycardia therapy were neither recorded nor visually observed during radiation. With a low-energy accelerator, neither malfunctions nor electromagnetic interferences were detected radiating the ICDs at doses usually reaching the ICD pocket during radiotherapy sessions. In this context, magnet application to avoid oversensing and inappropriate therapy seems, therefore, useless.

  12. Uterine Vascular Lesions

    Science.gov (United States)

    Vijayakumar, Abhishek; Srinivas, Amruthashree; Chandrashekar, Babitha Moogali; Vijayakumar, Avinash

    2013-01-01

    Vascular lesions of the uterus are rare; most reported in the literature are arteriovenous malformations (AVMs). Uterine AVMs can be congenital or acquired. In recent years, there has been an increasing number of reports of acquired vascular lesions of the uterus following pregnancy, abortion, cesarean delivery, and curettage. It can be seen from these reports that there is confusion concerning the terminology of uterine vascular lesions. There is also a lack of diagnostic criteria and management guidelines, which has led to an increased number of unnecessary invasive procedures (eg, angiography, uterine artery embolization, hysterectomy for abnormal vaginal bleeding). This article familiarizes readers with various vascular lesions of the uterus and their management. PMID:24340126

  13. Magnetic resonance vascular imaging

    International Nuclear Information System (INIS)

    Axel, L

    1989-01-01

    The basis principles of MRI are reviewed in order to understand how blood flow effects arise in conventional imaging. Then some of the ways these effects have ben used in MRI techniques specifically designed for vascular imaging, are considered. (author)

  14. Bir1 Deletion Causes Malfunction of the Spindle Assembly Checkpoint and Apoptosis in Yeast

    International Nuclear Information System (INIS)

    Ren, Qun; Liou, Liang-Chun; Gao, Qiuqiang; Bao, Xiaoming; Zhang, Zhaojie

    2012-01-01

    Cell division in yeast is a highly regulated and well studied event. Various checkpoints are placed throughout the cell cycle to ensure faithful segregation of sister chromatids. Unexpected events, such as DNA damage or oxidative stress, cause the activation of checkpoint(s) and cell cycle arrest. Malfunction of the checkpoints may induce cell death. We previously showed that under oxidative stress, the budding yeast cohesin Mcd1, a homolog of human Rad21, was cleaved by the caspase-like protease Esp1. The cleaved Mcd1 C-terminal fragment was then translocated to mitochondria, causing apoptotic cell death. In the present study, we demonstrated that Bir1 plays an important role in spindle assembly checkpoint and cell death. Similar to H 2 O 2 treatment, deletion of BIR1 using a BIR1-degron strain caused degradation of the securin Pds1, which binds and inactivates Esp1 until metaphase-anaphase transition in a normal cell cycle. BIR1 deletion caused an increase level of ROS and mis-location of Bub1, a major protein for spindle assembly checkpoint. In wild type, Bub1 was located at the kinetochores, but was primarily in the cytoplasm in bir1 deletion strain. When BIR1 was deleted, addition of nocodazole was unable to retain the Bub1 localization on kinetochores, further suggesting that Bir1 is required to activate and maintain the spindle assembly checkpoint. Our study suggests that the BIR1 function in cell cycle regulation works in concert with its anti-apoptosis function.

  15. Risk factors for shunt malfunction in pediatric hydrocephalus: a multicenter prospective cohort study.

    Science.gov (United States)

    Riva-Cambrin, Jay; Kestle, John R W; Holubkov, Richard; Butler, Jerry; Kulkarni, Abhaya V; Drake, James; Whitehead, William E; Wellons, John C; Shannon, Chevis N; Tamber, Mandeep S; Limbrick, David D; Rozzelle, Curtis; Browd, Samuel R; Simon, Tamara D

    2016-04-01

    OBJECT The rate of CSF shunt failure remains unacceptably high. The Hydrocephalus Clinical Research Network (HCRN) conducted a comprehensive prospective observational study of hydrocephalus management, the aim of which was to isolate specific risk factors for shunt failure. METHODS The study followed all first-time shunt insertions in children younger than 19 years at 6 HCRN centers. The HCRN Investigator Committee selected, a priori, 21 variables to be examined, including clinical, radiographic, and shunt design variables. Shunt failure was defined as shunt revision, subsequent endoscopic third ventriculostomy, or shunt infection. Important a priori-defined risk factors as well as those significant in univariate analyses were then tested for independence using multivariate Cox proportional hazard modeling. RESULTS A total of 1036 children underwent initial CSF shunt placement between April 2008 and December 2011. Of these, 344 patients experienced shunt failure, including 265 malfunctions and 79 infections. The mean and median length of follow-up for the entire cohort was 400 days and 264 days, respectively. The Cox model found that age younger than 6 months at first shunt placement (HR 1.6 [95% CI 1.1-2.1]), a cardiac comorbidity (HR 1.4 [95% CI 1.0-2.1]), and endoscopic placement (HR 1.9 [95% CI 1.2-2.9]) were independently associated with reduced shunt survival. The following had no independent associations with shunt survival: etiology, payer, center, valve design, valve programmability, the use of ultrasound or stereotactic guidance, and surgeon experience and volume. CONCLUSIONS This is the largest prospective study reported on children with CSF shunts for hydrocephalus. It confirms that a young age and the use of the endoscope are risk factors for first shunt failure and that valve type has no impact. A new risk factor-an existing cardiac comorbidity-was also associated with shunt failure.

  16. Treatment of the diabetic foot from a vascular surgeon's viewpoint.

    Science.gov (United States)

    Chang, B B; Shah, D M; Darling, R C; Leather, R P

    1993-11-01

    Diabetic foot lesions are caused by neurologic, orthopaedic, immunologic, and vascular derangements. Whereas some lesions may be initially caused by trauma and others directly caused by vascular disease, improvement of arterial perfusion often plays an important role in the successful salvage of these limbs. Fortunately, in the last several years, there has been a major improvement in the identification and treatment of those patients in whom correction of arterial occlusive disease is necessary for healing.

  17. Vascular lesions of head and neck: A literature review

    Directory of Open Access Journals (Sweden)

    Nazia Masoom Syed

    2016-01-01

    Full Text Available Vascular lesions are among the most common congenital and neonatal abnormalities. These anomalies can occur throughout the whole body, with 60%, however, being located in the head and neck region probably due to its intricate vascular anatomy of region. There is a significant confusion in the literature because of the use of confusing descriptive terminology for the same vascular entity and eponyms. Correct naming of lesion, appropriate classification, and clinical appearance of vascular lesions have a direct impact on understanding of etiologies of these complex lesions, diagnosis, and in treating patients. Thus, the aim of this article is to provide comprehensive knowledge about classifications and to have an insight of various important vascular lesions affecting head and neck region based on its pathogenesis, clinical presentation, and management.

  18. Data collection on component malfunctions and failures of JET ICRH system

    International Nuclear Information System (INIS)

    Pinna, T.; Cambi, G.

    2007-01-01

    The objective of the activity was to collect and analyse data coming out from operating experiences gained in the Joint European Torus (JET) for the Ion Cyclotron Resonance Heating (ICRH) system in order to enrich the data collection on failures of components used in fusion facilities. Alarms/Failures and malfunctions occurred in the years of operations from March 1996 to November 2005, including information on failure modes and, where possible, causes of the failures, have been identified. Beyond information on failures and alarms events, also data related to crowbar events have been collected. About 3400 events classified as alarms or failures related to specific components or sub-systems were identified by analysing the 25 hand-written logbooks made available by the ICRH operation staff. Information about the JET pulses in which the ICRH system was operated has been extracted from the tick sheets covering the whole considered time interval. 20 hand written tick sheets cover the period from March 1996 to middle May 2003, while tick sheets recorded as excel files cover the period from May 2003 to November 2005. By analysing the tick sheets it results that the ICRH was operated during about 12000 plasma pulses. Main statistical values, such as rates of alarms/failures and corresponding standard errors and confidence intervals, have been estimated. Failure rates of systems and components have been evaluated both with regard to the ICRH operation pulses and operating days (days in which at least one ICRH module was requested to operate). Failure probabilities on demand have been evaluated with regard to number of pulses operated. Some of the results are the following: - The highest number of alarms/failures (1243) appears to be related to Erratic /No-output of the Instrumentation and Control (I and C) apparatus, followed by faults (829) of the Tetrode circuits, by faults (466) of the High Voltage Power Supply system and by faults (428) of the Tuning elements. - The

  19. Overview of vascular disease

    International Nuclear Information System (INIS)

    Bisset, G.S. III

    1998-01-01

    Vascular disease in the pediatric population is a poorly understood process which is often underestimated in its incidence. The common beginnings of such ubiquitous diseases as atherosclerosis manifest themselves at a cellular level shortly after birth. Other common systemic disorders, including congestive heart failure and sepsis, are also intricately associated with dysfunctional vasculature. Progress in the understanding of normal and pathophysiologic processes within the vascular system begins with the 'control center' - the endothelial cell. The purpose of this review is to consolidate a body of knowledge on the processes that occur at the cellular level within the blood vessel wall, and to simplify the understanding of how imbalances in these physiologic parameters result in vascular disease. (orig.)

  20. Transient analysis of variable-speed wind turbines at wind speed disturbances and a pitch control malfunction

    International Nuclear Information System (INIS)

    Melicio, R.; Mendes, V.M.F.; Catalao, J.P.S.

    2011-01-01

    As wind power generation undergoes rapid growth, new technical challenges emerge: dynamic stability and power quality. The influence of wind speed disturbances and a pitch control malfunction on the quality of the energy injected into the electric grid is studied for variable-speed wind turbines with different power-electronic converter topologies. Additionally, a new control strategy is proposed for the variable-speed operation of wind turbines with permanent magnet synchronous generators. The performance of disturbance attenuation and system robustness is ascertained. Simulation results are presented and conclusions are duly drawn.

  1. Transient analysis of variable-speed wind turbines at wind speed disturbances and a pitch control malfunction

    Energy Technology Data Exchange (ETDEWEB)

    Melicio, R. [Department of Electromechanical Engineering, University of Beira Interior, R. Fonte do Lameiro, 6201-001 Covilha (Portugal); Mendes, V.M.F. [Department of Electrical Engineering and Automation, Instituto Superior de Engenharia de Lisboa, R. Conselheiro Emidio Navarro, 1950-062 Lisbon (Portugal); Catalao, J.P.S. [Department of Electromechanical Engineering, University of Beira Interior, R. Fonte do Lameiro, 6201-001 Covilha (Portugal); Center for Innovation in Electrical and Energy Engineering, Instituto Superior Tecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon (Portugal)

    2011-04-15

    As wind power generation undergoes rapid growth, new technical challenges emerge: dynamic stability and power quality. The influence of wind speed disturbances and a pitch control malfunction on the quality of the energy injected into the electric grid is studied for variable-speed wind turbines with different power-electronic converter topologies. Additionally, a new control strategy is proposed for the variable-speed operation of wind turbines with permanent magnet synchronous generators. The performance of disturbance attenuation and system robustness is ascertained. Simulation results are presented and conclusions are duly drawn. (author)

  2. Severe Intraoperative Hypercapnia Complicating an Unsual Malfunction of the Inner Tube of a Co-axial (BAIN'S Circuit

    Directory of Open Access Journals (Sweden)

    Youssef Emam Youssef

    2010-04-01

    Full Text Available The Bain's co-axial circuit system is fully established in general anaesthesia practice. It is favoured for its light weight and suitability for head and neck surgery. However, there are numerous published reports of malfunction of the inner tube of the Bain's co-axial circuit, with potentially lethal complications for the patient. This report presents a case in which a patient connected to a reused Bain's circuit (Datex-Ohmeda developed severe hypercapnia in the early intraoperative period due to unusual defect of the inner tube. This report tests and outlines the integrity of co-axial circuits and also reviews the available literature.

  3. Malfunctioning and infected tunneled infusion catheters: over-the-wire catheter exchange versus catheter removal and replacement.

    Science.gov (United States)

    Guttmann, David M; Trerotola, Scott O; Clark, Timothy W; Dagli, Mandeep; Shlansky-Goldberg, Richard D; Itkin, Maxim; Soulen, Michael C; Mondschein, Jeffrey I; Stavropoulos, S William

    2011-05-01

    To compare the safety and effectiveness of over-the-wire catheter exchange (catheter-exchange) with catheter removal and replacement (removal-replacement) at a new site for infected or malfunctioning tunneled infusion catheters. Using a quality assurance database, 61 patients with tunneled infusion catheters placed during the period July 2001 to June 2009 were included in this study. Patients receiving hemodialysis catheters were excluded. Catheter-exchange was performed in 25 patients, and same-day removal-replacement was performed in 36 patients. Data collected included demographic information, indication for initial catheter placement and replacement, dwell time for the new catheter, and ultimate fate of the new device. Statistical comparisons between the two cohorts were analyzed using the Kaplan-Meier technique and Fisher exact test. Catheters exchanged over the wire remained functional without infection for a median of 102 days (range, 2-570 days), whereas catheters removed and replaced were functional for a median 238 days (range, 1-292 days, P = .12). After catheter replacement, there were 11 instances of subsequent infection in the catheter-exchange group and 7 instances in the removal-replacement cohort, accounting for infection rates of 4.4 and 2.3 per 1,000 catheter days (P = .049). Patients in the catheter-exchange group had 3.2 greater odds of infection compared with patients in the removal-replacement group. Five malfunction events occurred in each group, accounting for 2.0 and 1.7 malfunctions per 1,000 catheter days in the catheter-exchange and removal-replacement groups (P = .73). Catheter-exchange of tunneled infusion catheters results in a higher infection rate compared with removal-replacement at a new site. The rate of catheter malfunction is not significantly different between the two groups. Catheter-exchange is an alternative for patients with tunneled infusion catheters who have limited venous access, but this technique should not be

  4. Analysis of licensee event reports related to nuclear generating station onsite electrical system malfunctions, 1976-1978

    International Nuclear Information System (INIS)

    Bickel, J.H.; Abbott, E.C.

    1981-07-01

    This report summarizes the evaluation requested by the ACRS of 1177 LERS, submitted over a three year period, which related to onsite electrical system malfunctions. The evaluation was carried out for the purposes of identifying specific failure modes and consequences, evaluating the assumptions used in WASH-1400 on the reliability of electrical equipment, and identifying specific sequences which are significant to plant safety. The analysis performed provides a more specific identification of onsite electrical system failure modes, sequences, and consequences than was established in WASH-1400

  5. Renal posttransplant's vascular complications

    Directory of Open Access Journals (Sweden)

    Bašić Dragoslav

    2003-01-01

    Full Text Available INTRODUCTION Despite high graft and recipient survival figures worldwide today, a variety of technical complications can threaten the transplant in the postoperative period. Vascular complications are commonly related to technical problems in establishing vascular continuity or to damage that occurs during donor nephrectomy or preservation [13]. AIM The aim of the presenting study is to evaluate counts and rates of vascular complications after renal transplantation and to compare the outcome by donor type. MATERIAL AND METHODS A total of 463 kidneys (319 from living related donor LD and 144 from cadaveric donor - CD were transplanted during the period between June 1975 and December 1998 at the Urology & Nephrology Institute of Clinical Centre of Serbia in Belgrade. Average recipients' age was 33.7 years (15-54 in LD group and 39.8 (19-62 in CD group. Retrospectively, we analyzed medical records of all recipients. Statistical analysis is estimated using Hi-squared test and Fischer's test of exact probability. RESULTS Major vascular complications including vascular anastomosis thrombosis, internal iliac artery stenosis, internal iliac artery rupture obliterant vasculitis and external iliac vein rupture were analyzed. In 25 recipients (5.4% some of major vascular complications were detected. Among these cases, 22 of them were from CD group vs. three from LD group. Relative rate of these complications was higher in CD group vs. LD group (p<0.0001. Among these complications dominant one was vascular anastomosis thrombosis which occurred in 18 recipients (17 from CD vs. one from LD. Of these recipients 16 from CD lost the graft, while the rest of two (one from each group had lethal outcome. DISCUSSION Thrombosis of renal allograft vascular anastomosis site is the most severe complication following renal transplantation. In the literature, renal allograft thrombosis is reported with different incidence rates, from 0.5-4% [14, 15, 16]. Data from the

  6. Non-native vascular plants from Canary Islands (Spain): nomenclatural and taxonomical adjustments

    OpenAIRE

    Verloove, F.

    2013-01-01

    Se propone correcciones taxonómicas y nomenclaturales respecto a 88 taxones no nativos de la lista de plantas vasculares de las Islas Canarias (España). Non-native vascular plants from Canary Islands (Spain): nomenclatural and taxonomical adjustments. Corrections and other adjustments are proposed for 88 non-native taxa from the checklist of vascular plants from the Canary Islands (Spain).

  7. Online Vibration Monitoring of a Water Pump Machine to Detect Its Malfunction Components Based on Artificial Neural Network

    Science.gov (United States)

    Rahmawati, P.; Prajitno, P.

    2018-04-01

    Vibration monitoring is a measurement instrument used to identify, predict, and prevent failures in machine instruments[6]. This is very needed in the industrial applications, cause any problem with the equipment or plant translates into economical loss and they are mostly monitored component off-line[2]. In this research, a system has been developed to detect the malfunction of the components of Shimizu PS-128BT water pump machine, such as capacitor, bearing and impeller by online measurements. The malfunction components are detected by taking vibration data using a Micro-Electro-Mechanical System(MEMS)-based accelerometer that are acquired by using Raspberry Pi microcomputer and then the data are converted into the form of Relative Power Ratio(RPR). In this form the signal acquired from different components conditions have different patterns. The collected RPR used as the base of classification process for recognizing the damage components of the water pump that are conducted by Artificial Neural Network(ANN). Finally, the damage test result will be sent via text message using GSM module that are connected to Raspberry Pi microcomputer. The results, with several measurement readings, with each reading in 10 minutes duration for each different component conditions, all cases yield 100% of accuracies while in the case of defective capacitor yields 90% of accuracy.

  8. Major Vascular Neurocognitive Disorder: A Reappraisal to Vascular Dementia

    Directory of Open Access Journals (Sweden)

    Emre Kumral

    2017-03-01

    Full Text Available Major vascular neurocognitive disorder (NCD is the second leading form of dementia after Alzheimer’s disease, accounting for 17-20% of all dementias. Vascular NCD is a progressive disease caused by reduced cerebral blood flow related to multiple large volume or lacunar infarcts that induce a sudden onset and stepwise decline in cognitive abilities. Despite its prevalence and clinical importance, there is still controversy in the terminology of vascular NCD. Only after the release of Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5 (2013 did the American Psychiatric Association define vascular dementia as “major vascular NCD”. This review includes an overview of risk factors, pathophysiology, types, diagnostic and clinical features of major vascular NCD, and current treatment options of vascular NCD regarding to DSM-5 criteria

  9. Vascular Neurology Nurse Practitioner Provision of Telemedicine Consultations

    Directory of Open Access Journals (Sweden)

    Bart M. Demaerschalk

    2010-01-01

    Full Text Available Objective. The objective was to define and evaluate a role for the Vascular Neurology-Nurse Practitioner (VN-NP in the delivery of telemedicine consultations in partnership with a vascular neurologist. Methods. Prospective stroke alert patients at participating hospitals underwent a two-way audio video telemedicine consultation with a VN-NP at a remotely located stroke center in partnership with a vascular neurologist. Demographic information, National Institutes of Health Stroke Scale (NIHSS scores, diagnoses, CT contraindications to thrombolysis, thrombolysis eligibility, and time interval data were collected. The inter-rater agreement between VN-NP and vascular neurologist assessments was calculated. Results. Ten patients were evaluated. Four were determined to have ischemic stroke, one had a transient ischemic attack, two had intracerebral hemorrhages, and three were stroke mimics. Overall, three patients received thrombolysis. The inter-rater agreement between VN-NP and vascular neurologist assessments were excellent, ranging from 0.9 to 1.0. The duration of VN-NP consultation was 53.2±9.0 minutes, which included the vascular neurologist supervisory evaluation time of 12.0±9.6 minutes. Conclusion. This study illustrated that a stroke center VN-NP, in partnership with a vascular neurologist, could deliver timely telemedicine consultations, accurate diagnoses, and correct treatments in acute stroke patients who presented to remotely located rural emergency departments within a hub and spoke network. VN-NPs may fulfill the role of a telestroke provider.

  10. Vascular neurology nurse practitioner provision of telemedicine consultations.

    Science.gov (United States)

    Demaerschalk, Bart M; Kiernan, Terri-Ellen J; Investigators, Starr

    2010-01-01

    Objective. The objective was to define and evaluate a role for the Vascular Neurology-Nurse Practitioner (VN-NP) in the delivery of telemedicine consultations in partnership with a vascular neurologist. Methods. Prospective stroke alert patients at participating hospitals underwent a two-way audio video telemedicine consultation with a VN-NP at a remotely located stroke center in partnership with a vascular neurologist. Demographic information, National Institutes of Health Stroke Scale (NIHSS) scores, diagnoses, CT contraindications to thrombolysis, thrombolysis eligibility, and time interval data were collected. The inter-rater agreement between VN-NP and vascular neurologist assessments was calculated. Results. Ten patients were evaluated. Four were determined to have ischemic stroke, one had a transient ischemic attack, two had intracerebral hemorrhages, and three were stroke mimics. Overall, three patients received thrombolysis. The inter-rater agreement between VN-NP and vascular neurologist assessments were excellent, ranging from 0.9 to 1.0. The duration of VN-NP consultation was 53.2 +/- 9.0 minutes, which included the vascular neurologist supervisory evaluation time of 12.0 +/- 9.6 minutes. Conclusion. This study illustrated that a stroke center VN-NP, in partnership with a vascular neurologist, could deliver timely telemedicine consultations, accurate diagnoses, and correct treatments in acute stroke patients who presented to remotely located rural emergency departments within a hub and spoke network. VN-NPs may fulfill the role of a telestroke provider.

  11. Plant Vascular Biology 2010

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Biao

    2014-11-17

    This grant supported the Second International Conference on Plant Vascular Biology (PVB 2010) held July 24-28, 2010 on the campus of Ohio State University, Columbus, Ohio. Biao Ding (Ohio State University; OSU) and David Hannapel (Iowa State University; ISU) served as co-chairs of this conference. Biao Ding served as the local organizer. PVB is defined broadly here to include studies on the biogenesis, structure and function of transport systems in plants, under conditions of normal plant growth and development as well as of plant interactions with pathogens. The transport systems cover broadly the xylem, phloem, plasmodesmata and vascular cell membranes. The PVB concept has emerged in recent years to emphasize the integrative nature of the transport systems and approaches to investigate them.

  12. Vascular cognitive impairment

    Directory of Open Access Journals (Sweden)

    N.V. Vakhnina

    2014-01-01

    Full Text Available Vascular pathology of the brain is the second most common cause of cognitive impairment after Alzheimer's disease. The article describes the modern concepts of etiology, pathogenetic mechanisms, clinical features and approaches to diagnosis and therapy of vascular cognitive impairment (VCI. Cerebrovascular accident, chronic cerebral circulatory insufficiency and their combination, sometimes in combination with a concomitant neurodegenerative process, are shown to be the major types of brain lesions leading to VCI. The clinical presentation of VCI is characterized by the neuropsychological status dominated by impairment of the executive frontal functions (planning, control, attention in combination with focal neurological symptoms. The diagnosis is based on comparing of the revealed neuropsychological and neurological features with neuroimaging data. Neurometabolic, acetylcholinergic, glutamatergic, and other vasoactive drugs and non-pharmacological methods are widely used to treat VCI. 

  13. Vascular Surgery and Robotics

    Directory of Open Access Journals (Sweden)

    Indrani Sen

    2016-01-01

    Full Text Available The application of robotics to Vascular surgery has not progressed as rapidly as of endovascular technology, but this is changing with the amalgamation of these two fields. The advent of Endovascular robotics is an exciting field which overcomes many of the limitations of endovascular therapy like vessel tortuosity and operator fatigue. This has much clinical appeal for the surgeon and hold significant promise of better patient outcomes. As with most newer technological advances, it is still limited by cost and availability. However, this field has seen some rapid progress in the last decade with the technology moving into the clinical realm. This review details the development of robotics, applications, outcomes, advantages, disadvantages and current advances focussing on Vascular and Endovascular robotics

  14. Vascular lesions following radiation

    International Nuclear Information System (INIS)

    Fajardo, L.F.; Berthrong, M.

    1988-01-01

    The special radiation sensitivity of the vascular system is mainly linked to that of endothelial cells, which are perhaps the most radiation-vulnerable elements of mesenchymal tissues. Within the vascular tree, radiation injures most often capillaries, sinusoids, and small arteries, in that order. Lesions of veins are observed less often, but in certain tissues the veins are regularly damaged (e.g., intestine) or are the most affected structures (i.e., liver). Large arteries do suffer the least; however, when significant damage does occur in an elastic artery (e.g., thrombosis or rupture), it tends to be clinically significant and even fatal. Although not always demonstrable in human tissues, radiation vasculopathy generally is dose and time dependent. Like other radiation-induced lesions, the morphology in the vessels is not specific, but it is characteristic enough to be often recognizable. Vascular injury, especially by therapeutic radiation is not just a morphologic marker. It is a mediator of tissue damage; perhaps the most consistent pathogenetic mechanism in delayed radiation injury

  15. Vascular lumen formation.

    Science.gov (United States)

    Lammert, Eckhard; Axnick, Jennifer

    2012-04-01

    The vascular system developed early in evolution. It is required in large multicellular organisms for the transport of nutrients, oxygen, and waste products to and from tissues. The vascular system is composed of hollow tubes, which have a high level of complexity in vertebrates. Vasculogenesis describes the de novo formation of blood vessels, e.g., aorta formation in vertebrate embryogenesis. In contrast, angiogenesis is the formation of blood vessels from preexisting ones, e.g., sprouting of intersomitic blood vessels from the aorta. Importantly, the lumen of all blood vessels in vertebrates is lined and formed by endothelial cells. In both vasculogenesis and angiogenesis, lumen formation takes place in a cord of endothelial cells. It involves a complex molecular mechanism composed of endothelial cell repulsion at the cell-cell contacts within the endothelial cell cords, junctional rearrangement, and endothelial cell shape change. As the vascular system also participates in the course of many diseases, such as cancer, stroke, and myocardial infarction, it is important to understand and make use of the molecular mechanisms of blood vessel formation to better understand and manipulate the pathomechanisms involved.

  16. Pulmonary vascular imaging

    International Nuclear Information System (INIS)

    Fedullo, P.F.; Shure, D.

    1987-01-01

    A wide range of pulmonary vascular imaging techniques are available for the diagnostic evaluation of patients with suspected pulmonary vascular disease. The characteristics of any ideal technique would include high sensitivity and specificity, safety, simplicity, and sequential applicability. To date, no single technique meets these ideal characteristics. Conventional pulmonary angiography remains the gold standard for the diagnosis of acute thromboembolic disease despite the introduction of newer techniques such as digital subtraction angiography and magnetic resonance imaging. Improved noninvasive lower extremity venous testing methods, particularly impedance plethysmography, and ventilation-perfusion scanning can play significant roles in the noninvasive diagnosis of acute pulmonary emboli when properly applied. Ventilation-perfusion scanning may also be useful as a screening test to differentiate possible primary pulmonary hypertension from chronic thromboembolic pulmonary hypertension. And, finally, angioscopy may be a useful adjunctive technique to detect chronic thromboembolic disease and determine operability. Optimal clinical decision-making, however, will continue to require the proper interpretation of adjunctive information obtained from the less-invasive techniques, applied with an understanding of the natural history of the various forms of pulmonary vascular disease and with a knowledge of the capabilities and shortcomings of the individual techniques

  17. LASER TREATMENT OF BENIGN CUTANEOUS VASCULAR LESIONS

    Directory of Open Access Journals (Sweden)

    Uroš Ahčan

    2004-07-01

    -up visit.Conclusions. In addition to clinical experience and correct diagnosis of the lesion, at least two lasers with different wavelengths are necessary for safe and efficient treatment of various cutaneous vascular lesions.The combination of the KTP (532 nm and Nd: YAG (1064 nm lasers incorporated in the Dualis VP® system offers great possibilities for treatment of various vascular anomalies on face, lower limbs, as well as other regions.

  18. Corrective Jaw Surgery

    Medline Plus

    Full Text Available ... and Craniofacial Surgery Cleft Lip/Palate and Craniofacial Surgery A cleft lip may require one or more ... find out more. Corrective Jaw Surgery Corrective Jaw Surgery Orthognathic surgery is performed to correct the misalignment ...

  19. Vascular remodeling and mineralocorticoids.

    Science.gov (United States)

    Weber, K T; Sun, Y; Campbell, S E; Slight, S H; Ganjam, V K

    1995-01-01

    Circulating mineralocorticoid hormones are so named because of their important homeostatic properties that regulate salt and water balance via their action on epithelial cells. A broader range of functions in nonclassic target cellular sites has been proposed for these steroids and includes their contribution to wound healing following injury. A chronic, inappropriate (relative to intravascular volume and dietary sodium intake) elevation of these circulating hormones evokes a wound healing response in the absence of tissue injury--a wound healing response gone awry. The adverse remodeling of vascularized tissues seen in association with chronic mineralocorticoid excess is the focus of this review.

  20. Development of the Australasian vascular surgical audit.

    Science.gov (United States)

    Bourke, Bernie M; Beiles, Charles Barry; Thomson, Ian A; Grigg, Michael J; Fitridge, Rob

    2012-01-01

    The purpose of this study was to describe the development of the Australasian Vascular Audit that was created to unify audit activities under the umbrella of the Australian and New Zealand Society for Vascular Surgery as a Web-based application. Constitutional change in late 2008 deemed participation in this audit compulsory for Society members. The Web-based application was developed and tested during 2009. Data for all open vascular surgery and for all endovascular procedures are collected at two points in the admission episode: at the time of operation and at discharge, and entered into the application. Data are analyzed to produce risk-adjusted outcomes. An algorithm has been developed to deal with outliers according to natural justice and to comply with the requirements of regulatory bodies. The Audit is protected by legislated privilege and is officially endorsed and indemnified by the Royal Australasian College of Surgeons. Confidentiality of surgeons and patients alike is ensured by a legally protected coding system and computer encryption system. Validation is by a verification process of 5% of members per year who are randomly selected. The application is completely funded by the Society. Data entry commenced on January 1, 2010. Over 40,000 vascular procedures were entered in the first year. The Audit application allows instantaneous on-line access to individual data and to deidentified group data and specific reports. It also allows real-time instantaneous production of log books for vascular trainees. The Audit has already gained recognition in the Australasian public arena during its first year of operation as an important benchmark of correct professional surgical behavior. Compliance has been extremely high in public hospitals but less so in private hospitals such that only 60% of members received a certificate of complete participation at the end of its first year of operation. An Internet-based compulsory audit of complete surgical practice is

  1. Interventional vascular radiology

    International Nuclear Information System (INIS)

    Yune, H.Y.

    1984-01-01

    The papers published during this past year in the area of interventional vascular radiology presented some useful modifications and further experiences both in the area of thromboembolic therapy and in dilation and thrombolysis, but no new techniques. As an introductory subject, an excellent monograph reviewing the current spectrum of pharmacoangiography was presented in Radiographics. Although the presented material is primarily in diagnostic application of various pharmacologic agents used today to facilitate demonstration of certain diagnostic criteria of various disease processes, both vasodilatory and vasoconstrictive reaction to these agents are widely used in various therapeutic vascular procedures. This monograph should be reviewed by every angiographer whether or not he or she performs interventional procedures, and it would be very convenient to have this table available in the angiography suite. In a related subject, Bookstein and co-workers have written an excellent review concerning pharmacologic manipulations of various blood coagulative parameters during angiography. Understanding the proper method of manipulation of the bloodclotting factors during angiography, and especially during interventional angiography, is extremely important. Particularly, the method of manipulating the coagulation with the use of heparin and protamine and modification of the platelet activity by using aspirin and dipyridamole are succinctly reviewed. The systemic and selective thrombolytic activities of streptokianse are also discussed

  2. Vascular dysfunction in preeclampsia.

    Science.gov (United States)

    Brennan, Lesley J; Morton, Jude S; Davidge, Sandra T

    2014-01-01

    Preeclampsia is a complex disorder which affects an estimated 5% of all pregnancies worldwide. It is diagnosed by hypertension in the presence of proteinuria after the 20th week of pregnancy and is a prominent cause of maternal morbidity and mortality. As delivery is currently the only known treatment, preeclampsia is also a leading cause of preterm delivery. Preeclampsia is associated with maternal vascular dysfunction, leading to serious cardiovascular risk both during and following pregnancy. Endothelial dysfunction, resulting in increased peripheral resistance, is an integral part of the maternal syndrome. While the cause of preeclampsia remains unknown, placental ischemia resulting from aberrant placentation is a fundamental characteristic of the disorder. Poor placentation is believed to stimulate the release of a number of factors including pro- and antiangiogenic factors and inflammatory activators into the maternal systemic circulation. These factors are critical mediators of vascular function and impact the endothelium in distinctive ways, including enhanced endothelial oxidative stress. The mechanisms of action and the consequences on the maternal vasculature will be discussed in this review. © 2013 John Wiley & Sons Ltd.

  3. Vascular Remodeling in Experimental Hypertension

    Directory of Open Access Journals (Sweden)

    Norma R. Risler

    2005-01-01

    Full Text Available The basic hemodynamic abnormality in hypertension is an increased peripheral resistance that is due mainly to a decreased vascular lumen derived from structural changes in the small arteries wall, named (as a whole vascular remodeling. The vascular wall is an active, flexible, and integrated organ made up of cellular (endothelial cells, smooth muscle cells, adventitia cells, and fibroblasts and noncellular (extracellular matrix components, which in a dynamic way change shape or number, or reorganize in response to physiological and pathological stimuli, maintaining the integrity of the vessel wall in physiological conditions or participating in the vascular changes in cardiovascular diseases such as hypertension. Research focused on new signaling pathways and molecules that can participate in the mechanisms of vascular remodeling has provided evidence showing that vascular structure is not only affected by blood pressure, but also by mechanisms that are independent of the increased pressure. This review will provide an overview of the evidence, explaining some of the pathophysiologic mechanisms participating in the development of the vascular remodeling, in experimental models of hypertension, with special reference to the findings in spontaneously hypertensive rats as a model of essential hypertension, and in fructose-fed rats as a model of secondary hypertension, in the context of the metabolic syndrome. The understanding of the mechanisms producing the vascular alterations will allow the development of novel pharmacological tools for vascular protection in hypertensive disease.

  4. Vascular pattern formation in plants.

    Science.gov (United States)

    Scarpella, Enrico; Helariutta, Ykä

    2010-01-01

    Reticulate tissue systems exist in most multicellular organisms, and the principles underlying the formation of cellular networks have fascinated philosophers, mathematicians, and biologists for centuries. In particular, the beautiful and varied arrangements of vascular tissues in plants have intrigued mankind since antiquity, yet the organizing signals have remained elusive. Plant vascular tissues form systems of interconnected cell files throughout the plant body. Vascular cells are aligned with one another along continuous lines, and vascular tissues differentiate at reproducible positions within organ environments. However, neither the precise path of vascular differentiation nor the exact geometry of vascular networks is fixed or immutable. Several recent advances converge to reconcile the seemingly conflicting predictability and plasticity of vascular tissue patterns. A control mechanism in which an apical-basal flow of signal establishes a basic coordinate system for body axis formation and vascular strand differentiation, and in which a superimposed level of radial organizing cues elaborates cell patterns, would generate a reproducible tissue configuration in the context of an underlying robust, self-organizing structure, and account for the simultaneous regularity and flexibility of vascular tissue patterns. Copyright 2010 Elsevier Inc. All rights reserved.

  5. Malfunction of a Heimlich flutter valve causing tension pneumothorax: case report of a rare complication

    Directory of Open Access Journals (Sweden)

    Braunstein Volker A

    2010-06-01

    Full Text Available Abstract Background Thoracic injuries play an important role in major trauma patients due to their high incidence and critical relevance. A serious consequence of thoracic trauma is pneumothorax, a condition that quickly can become life-threatening and requires immediate treatment. Decompression is the state of the art for treating tension pneumothorax. There are many different methods of decompression using different techniques, devices, valves and drainage systems. Referring to our case report we would like to discuss the utilization of these devices. Case presentation We report of a patient suffering from tension pneumothorax despite insertion of a chest drain at the accident scene. The decompression was by tube thoracostomy which was connected to a Heimlich flutter valve. During air transportation the patient suffered from cardiorespiratory arrest with asystole and was admitted to the trauma room undergoing manual chest compressions. The initial chest film showed a persisting tension pneumothorax, despite the chest tube that had been correctly placed and connected properly to the Heimlich valve. We assume that the Heimlich valve leaves did not open up and thus tension pneumothorax was not released. Conclusion We would like to raise awareness to the fact that if a Heimlich flutter valve is applied in the pre-hospital setting it should be used with caution. Failure in this type of valve may lead to recurrent tension pneumothorax.

  6. Additive Manufacturing of Vascular Grafts and Vascularized Tissue Constructs.

    Science.gov (United States)

    Elomaa, Laura; Yang, Yunzhi Peter

    2017-10-01

    There is a great need for engineered vascular grafts among patients with cardiovascular diseases who are in need of bypass therapy and lack autologous healthy blood vessels. In addition, because of the severe worldwide shortage of organ donors, there is an increasing need for engineered vascularized tissue constructs as an alternative to organ transplants. Additive manufacturing (AM) offers great advantages and flexibility of fabrication of cell-laden, multimaterial, and anatomically shaped vascular grafts and vascularized tissue constructs. Various inkjet-, extrusion-, and photocrosslinking-based AM techniques have been applied to the fabrication of both self-standing vascular grafts and porous, vascularized tissue constructs. This review discusses the state-of-the-art research on the use of AM for vascular applications and the key criteria for biomaterials in the AM of both acellular and cellular constructs. We envision that new smart printing materials that can adapt to their environment and encourage rapid endothelialization and remodeling will be the key factor in the future for the successful AM of personalized and dynamic vascular tissue applications.

  7. Cardiac and vascular malformations

    International Nuclear Information System (INIS)

    Ley, S.; Ley-Zaporozhan, J.

    2015-01-01

    Malformations of the heart and great vessels show a high degree of variation. There are numerous variants and defects with only few clinical manifestations and are only detected by chance, such as a persistent left superior vena cava or a partial anomalous pulmonary venous connection. Other cardiovascular malformations are manifested directly after birth and need prompt mostly surgical interventions. At this point in time echocardiography is the diagnostic modality of choice for morphological and functional characterization of malformations. Additional imaging using computed tomography (CT) or magnetic resonance imaging (MRI) is only required in a minority of cases. If so, the small anatomical structures, the physiological tachycardia and tachypnea are a challenge for imaging modalities and strategies. This review article presents the most frequent vascular, cardiac and complex cardiovascular malformations independent of the first line diagnostic imaging modality. (orig.) [de

  8. The predictive value of the radionuclide fistulogram (RnF) and its perioperative evaluation in arterio-venous fistulae (AVf) malfunction

    Energy Technology Data Exchange (ETDEWEB)

    Seo, I.S.; Sy, W.M.; Heneghan, W.; Manoli, A.

    1985-05-01

    The predictive value of the RnF in AVf malfunction was determined in 56 hemodialysis patients (77 studies). Two second dynamic images (qualitative) and concurrent 64 x 64 byte mode acquisition with .5 sec/frame for 1 min. (quantitative) were obtained following the administration of 15-20 mCi of Tc99m compounds (MDP or Tc04) into or near the AVf. Fourteen patients with clinical suspicion of AVf malfunction were referred for RnF. Eleven (78.6%) were abnormal and 3 were normal, based on previously established qualitative (collaterals, back flow and/or stenosis) and quantitative (S/sub 1//S/sub 2/<10%) criteria. Confirmatory contrast fistulogram (CnF) and surgical repair were done in 8/11. In three with normal studies, one had soft tissue abscesses near the venous orifice, another was attributed to malposition of needles at hemodialysis and no cause was apparent in the third. In 42 clinically unsuspected patients who were referred for other studies (bone scintigraphy and MUGA), nine (21.9%) had abnormal findings. Within three months, surgical repairs were made in four after CnF's confirmed AVf malfunction. The remaining five later developed signs of malfunction. 9 of 12 patients with surgical repairs had post surgical studies: 5 were normal while 2 remained abnormal even after a second surgical attempt; 2 had no follow up studies but were clinically asymptomatic. RnF is a simple benign imaging procedure with a high predictive value in documenting AVf malfunction in both symptomatic (78.9%) and in otherwise clinically unsuspected (21.9%) patients. Excellent clinical correlation in patients with surgical repairs is achieved.

  9. CIRSE Vascular Closure Device Registry

    NARCIS (Netherlands)

    Reekers, Jim A.; Müller-Hülsbeck, Stefan; Libicher, Martin; Atar, Eli; Trentmann, Jens; Goffette, Pierre; Borggrefe, Jan; Zeleňák, Kamil; Hooijboer, Pieter; Belli, Anna-Maria

    2011-01-01

    Vascular closure devices are routinely used after many vascular interventional radiology procedures. However, there have been no major multicenter studies to assess the safety and effectiveness of the routine use of closure devices in interventional radiology. The CIRSE registry of closure devices

  10. Dynamic adaption of vascular morphology

    DEFF Research Database (Denmark)

    Okkels, Fridolin; Jacobsen, Jens Christian Brings

    2012-01-01

    The structure of vascular networks adapts continuously to meet changes in demand of the surrounding tissue. Most of the known vascular adaptation mechanisms are based on local reactions to local stimuli such as pressure and flow, which in turn reflects influence from the surrounding tissue. Here ...

  11. Diagnostic criteria for vascular dementia

    NARCIS (Netherlands)

    Scheltens, P.; Hijdra, A. H.

    1998-01-01

    The term vascular dementia implies the presence of a clinical syndrome (dementia) caused by, or at least assumed to be caused by, a specific disorder (cerebrovascular disease). In this review, the various sets of criteria used to define vascular dementia are outlined. The various sets of criteria

  12. The vascular secret of Klotho

    DEFF Research Database (Denmark)

    Lewin, Ewa; Olgaard, Klaus

    2015-01-01

    Klotho is an evolutionarily highly conserved protein related to longevity. Increasing evidence of a vascular protecting effect of the Klotho protein has emerged and might be important for future treatments of uremic vascular calcification. It is still disputed whether Klotho is locally expressed ...

  13. Social media in vascular surgery.

    Science.gov (United States)

    Indes, Jeffrey E; Gates, Lindsay; Mitchell, Erica L; Muhs, Bart E

    2013-04-01

    There has been a tremendous growth in the use of social media to expand the visibility of various specialties in medicine. The purpose of this paper is to describe the latest updates on some current applications of social media in the practice of vascular surgery as well as existing limitations of use. This investigation demonstrates that the use of social networking sites appears to have a positive impact on vascular practice, as is evident through the incorporation of this technology at the Cleveland Clinic and by the Society for Vascular Surgery into their approach to patient care and physician communication. Overall, integration of social networking technology has current and future potential to be used to promote goals, patient awareness, recruitment for clinical trials, and professionalism within the specialty of vascular surgery. Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

  14. High-field MR imaging of spinal cord vascular lesions

    International Nuclear Information System (INIS)

    Blas, C.; Halimi, P.; Sigal, R.; Doyon, D.; Hurth, M.

    1986-01-01

    MR imaging (1.5T) was performed in 20 patients with spinal cord vascular malformations and hemangioblastomas. MR imaging findings were correlated with data obtained by other imaging modalities (myelography, CT and selective angiography). A diagnosis of vascular legions was suspected or established in 15 patients. Seven had a history of embolization or surgery prior to MR imaging. Six of seven hemangioblastomas were detected on MR imaging. The diagnosis was incorrect in one case because of the small size of the hemangioblastoma nodule, although the cystic part of the lesion was correctly identified. In three cases, the diagnosis was made first on MR imaging and then confirmed on angiography and surgery. Eleven vascular malformations were studied. Malformative thrombosis was found in four of the 11, as suggested by high-intensity signals on T1- and T2-weighted images

  15. Chronic Supplementation of Paeonol Combined with Danshensu for the Improvement of Vascular Reactivity in the Cerebral Basilar Artery of Diabetic Rats

    Science.gov (United States)

    Hu, Jing; Li, Ya-Ling; Li, Zi-Lin; Li, Hua; Zhou, Xuan-Xuan; Qiu, Peng-Cheng; Yang, Qian; Wang, Si-Wang

    2012-01-01

    One of the leading causes of death in the world is cerebrovascular disease. Numerous Chinese traditional medicines, such as Cortex Moutan (root bark of Paeonia suffruticosa Andrew) and Radix Salviae miltiorrhizae (root and rhizome of Salvia miltiorrhiza Bunge), protect against cerebrovascular diseases and exhibit anti-atherosclerotic effects. Traditional medicines have been routinely used for a long time in China. In addition, these two herbs are prescribed together in clinical practice. Therefore, the pharmacodynamic interactions between the active constituents of these two herbs, which are paeonol (Pae) and danshensu (DSS), should be particularly studied. The study of Pae and DSS can provide substantial foundations in understanding their mechanisms and empirical evidence to support clinical practice. This study investigated the effects and possible mechanisms of the pharmacodynamic interaction between Pae and DSS on cerebrovascular malfunctioning in diabetes. Experimental diabetes was induced in rats, which was then treated with Pae, DSS, and Pae + DSS for eight weeks. Afterward, cerebral arteries from all groups were isolated and equilibrated in an organ bath with Krebs buffer and ring tension. Effects of Pae, DSS, and Pae + DSS were observed on vessel relaxation with or without endothelium as well as on the basal tonus of vessels from normal and diabetic rats. Indexes about oxidative stress were also determined. We report that the cerebral arteries from diabetic rats show decreased vascular reactivity to acetylcholine (ACh) which was corrected in Pae, DSS, and Pae + DSS treated groups. Furthermore, phenylephrine (PE)-induced contraction response decreased in the treated groups. Phenylephrine and CaCl2-induced vasoconstrictions are partially inhibited in the three treated groups under Ca2+-free medium. Pre-incubated with tetraethylammonium, a non-selective K+ channel blocker, the antagonized relaxation responses increased in DSS and Pae + DSS treated diabetic

  16. Design and application of model for training ultrasound-guided vascular cannulation in pediatric patients.

    Science.gov (United States)

    Pérez-Quevedo, O; López-Álvarez, J M; Limiñana-Cañal, J M; Loro-Ferrer, J F

    2016-01-01

    Central vascular cannulation is not a risk-free procedure, especially in pediatric patients. Newborn and infants are small and low-weighted, their vascular structures have high mobility because of tissue laxity and their vessels are superficial and with small diameter. These characteristics, together with the natural anatomical variability and poor collaboration of small children, make this technique more difficult to apply. Therefore, ultrasound imaging is increasingly being used to locate vessels and guide vascular access in this population. (a) To present a model that simulates the vascular system for training ultrasound-guided vascular access in pediatrics patients; (b) to ultrasound-guided vascular cannulation in the model. The model consisted of two components: (a) muscular component: avian muscle, (b) vascular component: elastic tube-like structure filled with fluid. 864 ecoguided punctures was realized in the model at different vessel depth and gauge measures were simulated, for two medical operators with different degree of experience. The average depth and diameter of vessel cannulated were 1.16 (0.42)cm and 0.43 (0.1)cm, respectively. The average number of attempts was of 1.22 (0.62). The percentage of visualization of the needle was 74%. The most frequent maneuver used for the correct location, was the modification of the angle of the needle and the relocation of the guidewire in 24% of the cases. The average time for the correct cannulations was 41 (35.8)s. The more frequent complications were the vascular perforation (11.9%) and the correct vascular puncture without possibility of introducing the guidewire (1.2%). The rate of success was 96%. The model simulates the anatomy (vascular and muscular structures) of a pediatric patient. It is cheap models, easily reproducible and a useful tool for training in ultrasound-guided puncture and cannulation. Copyright © 2015 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  17. NWS Corrections to Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Form B-14 is the National Weather Service form entitled 'Notice of Corrections to Weather Records.' The forms are used to make corrections to observations on forms...

  18. Corrective Jaw Surgery

    Medline Plus

    Full Text Available ... more surgeries depending on the extent of the repair needed. Click here to find out more. Corrective ... more surgeries depending on the extent of the repair needed. Click here to find out more. Corrective ...

  19. Corrective Jaw Surgery

    Medline Plus

    Full Text Available ... Jaw Surgery Download Download the ebook for further information Corrective jaw, or orthognathic surgery is performed by ... your treatment. Correction of Common Dentofacial Deformities ​ ​ The information provided here is not intended as a substitute ...

  20. Transforming growth factor β family members in regulation of vascular function: in the light of vascular conditional knockouts.

    Science.gov (United States)

    Jakobsson, Lars; van Meeteren, Laurens A

    2013-05-15

    Blood vessels are composed of endothelial cells, mural cells (smooth muscle cells and pericytes) and their shared basement membrane. During embryonic development a multitude of signaling components orchestrate the formation of new vessels. The process is highly dependent on correct dosage, spacing and timing of these signaling molecules. As vessels mature some cascades remain active, albeit at very low levels, and may be reactivated upon demand. Members of the Transforming growth factor β (TGF-β) protein family are strongly engaged in developmental angiogenesis but are also regulators of vascular integrity in the adult. In humans various genetic alterations within this protein family cause vascular disorders, involving disintegration of vascular integrity. Here we summarize and discuss recent data gathered from conditional and endothelial cell specific genetic loss-of-function of members of the TGF-β family in the mouse. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Vascular disease in cocaine addiction.

    Science.gov (United States)

    Bachi, Keren; Mani, Venkatesh; Jeyachandran, Devi; Fayad, Zahi A; Goldstein, Rita Z; Alia-Klein, Nelly

    2017-07-01

    Cocaine, a powerful vasoconstrictor, induces immune responses including cytokine elevations. Chronic cocaine use is associated with functional brain impairments potentially mediated by vascular pathology. Although the Crack-Cocaine epidemic has declined, its vascular consequences are increasingly becoming evident among individuals with cocaine use disorder of that period, now aging. Paradoxically, during the period when prevention efforts could make a difference, this population receives psychosocial treatment at best. We review major postmortem and in vitro studies documenting cocaine-induced vascular toxicity. PubMed and Academic Search Complete were used with relevant terms. Findings consist of the major mechanisms of cocaine-induced vasoconstriction, endothelial dysfunction, and accelerated atherosclerosis, emphasizing acute, chronic, and secondary effects of cocaine. The etiology underlying cocaine's acute and chronic vascular effects is multifactorial, spanning hypertension, impaired homeostasis and platelet function, thrombosis, thromboembolism, and alterations in blood flow. Early detection of vascular disease in cocaine addiction by multimodality imaging is discussed. Treatment may be similar to indications in patients with traditional risk-factors, with few exceptions such as enhanced supportive care and use of benzodiazepines and phentolamine for sedation, and avoiding β-blockers. Given the vascular toxicity cocaine induces, further compounded by smoking and alcohol comorbidity, and interacting with aging of the crack generation, there is a public health imperative to identify pre-symptomatic markers of vascular impairments in cocaine addiction and employ preventive treatment to reduce silent disease progression. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. [The future of vascular medicine].

    Science.gov (United States)

    Kroeger, K; Luther, B

    2014-10-01

    In the future vascular medicine will still have a great impact on health of people. It should be noted that the aging of the population does not lead to a dramatic increase in patient numbers, but will be associated with a changing spectrum of co-morbidities. In addition, vascular medical research has to include the intensive care special features of vascular patients, the involvement of vascular medicine in a holistic concept of fast-track surgery, a geriatric-oriented intensive monitoring and early geriatric rehabilitation. For the future acceptance of vascular medicine as a separate subject area under delimitation of cardiology and radiology is important. On the other hand, the subject is so complex and will become more complex in future specialisations that mixing of surgery and angiology is desirable, with the aim to preserve the vascular surgical knowledge and skills on par with the medical and interventional measures and further develop them. Only large, interdisciplinary guided vascular centres will be able to provide timely diagnosis and therapy, to deal with the growing multi-morbidity of the patient, to perform complex therapies even in an acute emergency and due to sufficient number of cases to present with well-trained and experienced teams. These requirements are mandatory to decrease patients' mortality step by step. Georg Thieme Verlag KG Stuttgart · New York.

  3. Contemporary vascular smartphone medical applications.

    Science.gov (United States)

    Carter, Thomas; O'Neill, Stephen; Johns, Neil; Brady, Richard R W

    2013-08-01

    Use of smartphones and medical mHealth applications (apps) within the clinical environment provides a potential means for delivering elements of vascular care. This article reviews the contemporary availability of apps specifically themed to major vascular diseases and the opportunities and concerns regarding their integration into practice. Smartphone apps relating to major vascular diseases were identified from the app stores for the 6 most popular smartphone platforms, including iPhone, Android, Blackberry, Nokia, Windows, and Samsung. Search terms included peripheral artery (arterial) disease, varicose veins, aortic aneurysm, carotid artery disease, amputation, ulcers, hyperhydrosis, thoracic outlet syndrome, vascular malformation, and lymphatic disorders. Forty-nine vascular-themed apps were identified. Sixteen (33%) were free of charge. Fifteen apps (31%) had customer satisfaction ratings, but only 3 (6%) had greater than 100. Only 13 apps (27%) had documented medical professional involvement in their design or content. The integration of apps into the delivery of care has the potential to benefit vascular health care workers and patients. However, high-quality apps designed by clinicians with vascular expertise are currently lacking and represent an area of concern in the mHealth market. Improvement in the quality and reliability of these apps will require the development of robust regulation. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Constructal vascularized structures

    Science.gov (United States)

    Cetkin, Erdal

    2015-06-01

    Smart features such as self-healing and selfcooling require bathing the entire volume with a coolant or/and healing agent. Bathing the entire volume is an example of point to area (or volume) flows. Point to area flows cover all the distributing and collecting kinds of flows, i.e. inhaling and exhaling, mining, river deltas, energy distribution, distribution of products on the landscape and so on. The flow resistances of a point to area flow can be decreased by changing the design with the guidance of the constructal law, which is the law of the design evolution in time. In this paper, how the flow resistances (heat, fluid and stress) can be decreased by using the constructal law is shown with examples. First, the validity of two assumptions is surveyed: using temperature independent Hess-Murray rule and using constant diameter ducts where the duct discharges fluid along its edge. Then, point to area types of flows are explained by illustrating the results of two examples: fluid networks and heating an area. Last, how the structures should be vascularized for cooling and mechanical strength is documented. This paper shows that flow resistances can be decreased by morphing the shape freely without any restrictions or generic algorithms.

  5. Therapeutic application of 99Tc-MDP in advanced nodose rheumatoid patients with multiple arthrosis erosion and malfunctioning

    International Nuclear Information System (INIS)

    Yuan Jiming

    2001-01-01

    Objective: To evaluate clinical effect of 99 Tc-MDP in treating arthrosis erosion in advanced nodose rheumatism. Methods: Therapy was performed undisrupted for 1 to 2 years in each patient at a high dose of 1.0-1.5 g/month. Results: After more than 1 year's 99 Tc-MDP therapy, 10 patients with multiple arthrosis erosion and serious malfunctioning had function recovery and arthral reformation of different extent. Patients with obvious therapeutic effects were able to walk, travel and completely or partially took care of themselves. Cortisone was prohibited or permitted at a lower dose of 1.25 mg/day in 3 patients who were dependant on prednisone. As results from 99 Tc-MDP therapy, X-ray photography revealed broadened arthral gap, reformation of previously eroded arthrosis and even improvement in osteoporosis. Conclusion: Reversible changes resulted from 99 Tc-MDP therapy showed breakthrough in treatment of advanced nodose rheumatism and serious ostearthritis, whose pathological changes were previously considered irreversible

  6. Malfunction and failure in regulation and protection systems of PHWRs -identification of deficient areas and suggested scope of improvements

    International Nuclear Information System (INIS)

    Jain, A.K.; Prabhat Kumar; Arya, R.C.

    1997-01-01

    The reactor regulation and protection systems have changed significantly in Narora Atomic Power Station type of reactors as compared to RAPS design. As compared to total negative reactivity worth offered by moderator dump for reactor shutdown in Rajasthan Atomic Power Station, the worth of the two fast acting shutdown systems (PSS and SSS) is far lesser. In fact the worth is not even adequate to maintain the shutdown indefinitely. This has necessitated incorporation of two slow acting systems for reactor regulation and protection i.e. ALPS and GRAB systems. The negative reactivity insertion rate from fast acting PSS and SSS is however much faster as compared to moderator dump. The above changes have brought about significant changes in reactivity devices and also associated problems due to larger number of systems and equipment. The layout has also become very congested on the top of calandria vault making maintenance and inspection more cumbersome. The paper highlights the malfunction and deficiencies observed in PSS, SSS and regulating rods and identifies the further scope of improvement. (author)

  7. Imaging findings and therapeutic alternatives for peripheral vascular malformations

    International Nuclear Information System (INIS)

    Monsignore, Lucas Moretti; Nakiri, Guilherme Seizem; Santos, Daniela dos; Abud, Thiago Giansante; Abud, Daniel Giansante

    2010-01-01

    Peripheral vascular malformations represent a spectrum of lesions that appear through the lifetime and can be found in the whole body. Such lesions are uncommon and are frequently confounded with infantile hemangioma, a common benign neoplastic lesion. In the presence of such lesions, the correlation between the clinical and radiological findings is extremely important to achieve a correct diagnosis, which will guide the best therapeutic approach. The most recent classifications for peripheral vascular malformations are based on the blood flow (low or high) and on the main vascular components (arterial, capillary, lymphatic or venous). Peripheral vascular malformations represent a diagnostic and therapeutic challenge, and complementary methods such as computed tomography, Doppler ultrasonography and magnetic resonance imaging, in association with clinical findings can provide information regarding blood flow characteristics and lesions extent. Arteriography and venography confirm the diagnosis, evaluate the lesions extent and guide the therapeutic decision making. Generally, low flow vascular malformations are percutaneously treated with sclerosing agents injection, while in high flow lesions the approach is endovascular, with permanent liquid or solid embolization agents. (author)

  8. Gait and Equilibrium in Subcortical Vascular Dementia

    Directory of Open Access Journals (Sweden)

    Rita Moretti

    2011-01-01

    Full Text Available Subcortical vascular dementia is a clinical entity, widespread, even challenging to diagnose and correctly treat. Patients with this diagnosis are old, frail, often with concomitant pathologies, and therefore, with many drugs in therapy. We tried to diagnose and follow up for three years more than 600 patients. Study subjects were men and women, not bedridden, aged 68–94 years, outpatients, recruited from June, 1st 2007 to June, 1st 2010. We examined them clinically, neurologically, with specific consideration on drug therapies. Our aim has been to define gait and imbalance problem, if eventually coexistent with the pathology of white matter and/or with the worsening of the deterioration. Drug intake interference has been detected and considered.

  9. [Central blood pressure and vascular damage].

    Science.gov (United States)

    Pérez-Lahiguera, Francisco; Rodilla, Enrique; Costa, José Antonio; Pascual, José María

    2015-07-20

    The aim of this study was to assess the relationship between central blood pressure and vascular damage. This cross-sectional study involved 393 never treated hypertensive patients (166 women). Clinical blood pressure (BP), 24h blood pressure (BP24h) and central blood pressure (CBP) were measured. Vascular organ damage (VOD) was assessed by calculating the albumin/creatinine ratio (ACR), wave pulse pressure velocity and echocardiographic left ventricular mass index (LVMI). Patients with VOD had higher values of BP, BP24h, and CBP than patients without ACR. When comparing several systolic BP, systolic BP24h had a higher linear correlation with CBP (Z Steiger test: 2.26; P=.02) and LVMI (Z Steiger test: 3.23; P=.01) than PAC. In a multiple regression analysis corrected by age, sex and metabolic syndrome, all pressures were related with VOD but systolic BP24h showed the highest correlation. In a logistic regression analysis, having the highest tercile of systolic BP24h was the stronger predictor of VOD (multivariate odds ratio: 3.4; CI 95%: 2.5-5.5, P=.001). CBP does not have more correlation with VOD than other measurements of peripheral BP. Systolic BP24h is the BP measurement that best predicts VOD. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  10. Diabetes and Retinal Vascular Dysfunction

    Directory of Open Access Journals (Sweden)

    Eui Seok Shin

    2014-01-01

    Full Text Available Diabetes predominantly affects the microvascular circulation of the retina resulting in a range of structural changes unique to this tissue. These changes ultimately lead to altered permeability, hyperproliferation of endothelial cells and edema, and abnormal vascularization of the retina with resulting loss of vision. Enhanced production of inflammatory mediators and oxidative stress are primary insults with significant contribution to the pathogenesis of diabetic retinopathy (DR. We have determined the identity of the retinal vascular cells affected by hyperglycemia, and have delineated the cell autonomous impact of high glucose on function of these cells. We discuss some of the high glucose specific changes in retinal vascular cells and their contribution to retinal vascular dysfunction. This knowledge provides novel insight into the molecular and cellular defects contributing to the development and progression of diabetic retinopathy, and will aid in the development of innovative, as well as target specific therapeutic approaches for prevention and treatment of DR.

  11. Vascular graft infections with Mycoplasma

    DEFF Research Database (Denmark)

    Levi-Mazloum, Niels Donald; Skov Jensen, J; Prag, J

    1995-01-01

    laboratory techniques, the percentage of culture-negative yet grossly infected vascular grafts seems to be increasing and is not adequately explained by the prior use of antibiotics. We have recently reported the first case of aortic graft infection with Mycoplasma. We therefore suggest the hypothesis...... that the large number of culture-negative yet grossly infected vascular grafts may be due to Mycoplasma infection not detected with conventional laboratory technique....

  12. Limb vascular function in women

    DEFF Research Database (Denmark)

    Hellsten, Ylva; Gliemann, Lasse

    2018-01-01

    Throughout life, women are subjected to both acute fluctuations in sex hormones, associated with the menstrual cycle, and chronic changes following the onset of menopause. Female sex hormones, and in particular estrogen, strongly influence cardiovascular function such as the regulation of vascular...... studies. Physical activity should be recommended for women of all ages, but the most essential timing for maintenance of vascular health may be from menopause and onwards....

  13. Facial vascular malformations in children

    International Nuclear Information System (INIS)

    Brunelle, F.O.; Lallemand, D.; Chaumont, P.; Teillac, D.; Manach, Y.

    1988-01-01

    The authors present their experience with conventional and digital angiography of vascular malformations of the head and neck in children. 22 hemangioendotheliomas, 8 venous angiomas, and 3 arteriovenous fistula were studied. 22 patients were embolised. DSA offers many advantages during the diagnostic as well as during the therapeutic phase of angiography. Embolization appears to have a major role in treatment of such vascular malformations. (orig.)

  14. Angiogenesis, Cancer, and Vascular Aging

    Directory of Open Access Journals (Sweden)

    Junji Moriya

    2017-10-01

    Full Text Available Several lines of evidence have revealed that the angiogenic response to ischemic injury declines with age, which might account for the increased morbidity and mortality of cardiovascular disease (CVD among the elderly. While impairment of angiogenesis with aging leads to delayed wound healing or exacerbation of atherosclerotic ischemic diseases, it also inhibits the progression of cancer. Age-related changes of angiogenesis have been considered to at least partly result from vascular aging or endothelial cell senescence. There is considerable evidence supporting the hypothesis that vascular cell senescence contributes to the pathogenesis of age-related CVD, suggesting that vascular aging could be an important therapeutic target. Since therapeutic angiogenesis is now regarded as a promising concept for patients with ischemic CVD, it has become even more important to understand the detailed molecular mechanisms underlying impairment of angiogenesis in older patients. To improve the usefulness of therapeutic angiogenesis, approaches are needed that can compensate for impaired angiogenic capacity in the elderly while not promoting the development or progression of malignancy. In this review, we briefly outline the mechanisms of angiogenesis and vascular aging, followed by a description of how vascular aging leads to impairment of angiogenesis. We also examine potential therapeutic approaches that could enhance angiogenesis and/or vascular function in the elderly, as well as discussing the possibility of anti-senescence therapy or reversal of endothelial cell senescence.

  15. The use of heteroduplex analysis of polymerase chain reaction products to support the possible transmission of Legionella pneumophila from a malfunctioning automobile air conditioner.

    Science.gov (United States)

    Pinar, Ahmet; Ramirez, Julio A; Schindler, Laura L; Miller, Richard D; Summersgill, James T

    2002-03-01

    Air conditioner condensates have not been previously associated with cases of Legionnaires' disease. We report the possible transmission of Legionella pneumophila serogroup 1 from a malfunctioning automobile air conditioning system's leaking water onto the floorboard of a car driven for a long distance by the patient. Heteroduplex analysis of polymerase chain reaction products was used to help establish an epidemiologic link between the water specimen and the patient.

  16. Vascular anomalies associated with epilepsy - case report

    International Nuclear Information System (INIS)

    Drgova, M.; Polacek, H.; Stevik, M.; Zelenak, K.

    2014-01-01

    Epilepsy is a common neurological disorder in which the individual has recurrent seizures. These seizures occur when there is an imbalance in the electrical activity of the brain. The malfunction may be in a small area of the brain or spread to the entire brain. Epilepsy usually begins in childhood or adolescence. About 2.3 million people have seizures or epilepsy. (author)

  17. Calcium dynamics in vascular smooth muscle

    OpenAIRE

    Amberg, Gregory C.; Navedo, Manuel F.

    2013-01-01

    Smooth muscle cells are ultimately responsible for determining vascular luminal diameter and blood flow. Dynamic changes in intracellular calcium are a critical mechanism regulating vascular smooth muscle contractility. Processes influencing intracellular calcium are therefore important regulators of vascular function with physiological and pathophysiological consequences. In this review we discuss the major dynamic calcium signals identified and characterized in vascular smooth muscle cells....

  18. Injuries to the vascular endothelium: vascular wall and endothelial dysfunction.

    Science.gov (United States)

    Fisher, Mark

    2008-01-01

    Vascular endothelial injury has multiple elements, and this article focuses on ischemia-related processes that have particular relevance to ischemic stroke. Distinctions between necrotic and apoptotic cell death provide a basic science context in which to better understand the significance of classical core and penumbra concepts of acute stroke, with apoptotic processes particularly prominent in the penumbra. The mitochondria are understood to serve as a reservoir of proteins that mediate apoptosis. Oxidative stress pathways generating reactive oxygen species (ROS) are prominent in endothelial injury, both ischemic and nonischemic, with prominent roles of enzyme- and nonenzymemediated pathways; mitochondria once again have a critical role, particularly in the nonenzymatic pathways generating ROS. Inflammation also contributes to vascular endothelial injury, and endothelial cells have the capacity to rapidly increase expression of inflammatory mediators following ischemic challenge; this leads to enhanced leukocyte-endothelial interactions mediated by selectins and adhesion molecules. Preconditioning consists of a minor version of an injurious event, which in turn may protect vascular endothelium from injury following a more substantial event. Presence of the blood-brain barrier creates unique responses to endothelial injury, with permeability changes due to impairment of endothelial-matrix interactions compounding altered vasomotor tone and tissue perfusion mediated by nitric oxide. Pharmacological protection against vascular endothelial injury can be provided by several of the phosphodiesterases (cilostazol and dipyridamole), along with statins. Optimal clinical responses for protection of brain vascular endothelium may use preconditioning as a model, and will likely require combined protection against apoptosis, ROS, and inflammation.

  19. Non-invasive vascular imaging: assessing tumour vascularity

    International Nuclear Information System (INIS)

    Delorme, S.; Knopp, M.V.

    1998-01-01

    Non-invasive assessment of vascularity is a new diagnostic approach to characterise tumours. Vascular assessment is based on the pathophysiology of tumour angiogenesis and its diagnostic implications for tumour biology, prognosis and therapy response. Two current techniques investigating vascular features in addition to morphology are Doppler ultrasonography and contrast-enhanced MRI. Diagnostic differentiation has been shown to be possible with Doppler, and a high degree of observed vascularity could be linked to an aggressive course of the disease. Dynamic MRI using gadolinium chelates is already used clinically to detect and differentiate tumours. The histological correlation shows that capillary permeability is increased in malignant tumours and is the best criterion for differentiation from benign processes. Permeability and perfusion factors seem to be more diagnostic than overall vessel density. New clinical applications are currently being established for therapy monitoring. Further instrumental developments will bring harmonic imaging in Doppler, and faster imaging techniques, higher spatial resolution and novel pharmacokinetic concepts in MRI. Upcoming contrast agents for both Doppler and MRI will further improve estimation of intratumoural blood volume and vascular permeability. (orig.)

  20. Corrections to primordial nucleosynthesis

    International Nuclear Information System (INIS)

    Dicus, D.A.; Kolb, E.W.; Gleeson, A.M.; Sudarshan, E.C.G.; Teplitz, V.L.; Turner, M.S.

    1982-01-01

    The changes in primordial nucleosynthesis resulting from small corrections to rates for weak processes that connect neutrons and protons are discussed. The weak rates are corrected by improved treatment of Coulomb and radiative corrections, and by inclusion of plasma effects. The calculations lead to a systematic decrease in the predicted 4 He abundance of about ΔY = 0.0025. The relative changes in other primoridal abundances are also 1 to 2%

  1. Pediatric interventional radiology: vascular interventions

    International Nuclear Information System (INIS)

    Kandasamy, Devasenathipathy; Gamanagatti, Shivanand; Gupta, Arun Kumar

    2016-01-01

    Pediatric interventional radiology (PIR) comprises a range of minimally invasive diagnostic and therapeutic procedures that are performed using image guidance. PIR has emerged as an essential adjunct to various surgical and medical conditions. Over the years, technology has undergone dramatic and continuous evolution, making this speciality grow. In this review, the authors will discuss various vascular interventional procedures undertaken in pediatric patients. It is challenging for the interventional radiologist to accomplish a successful interventional procedure. There are many vascular interventional radiology procedures which are being performed and have changed the way the diseases are managed. Some of the procedures are life saving and have become the treatment of choice in those patients. The future is indeed bright for the practice and practitioners of pediatric vascular and non-vascular interventions. As more and more of the procedures that are currently being performed in adults get gradually adapted for use in the pediatric population, it may be possible to perform safe and successful interventions in many of the pediatric vascular lesions that are otherwise being referred for surgery. (author)

  2. Publisher Correction: Predicting unpredictability

    Science.gov (United States)

    Davis, Steven J.

    2018-06-01

    In this News & Views article originally published, the wrong graph was used for panel b of Fig. 1, and the numbers on the y axes of panels a and c were incorrect; the original and corrected Fig. 1 is shown below. This has now been corrected in all versions of the News & Views.

  3. Fetal origin of vascular aging

    Directory of Open Access Journals (Sweden)

    Shailesh Pitale

    2011-01-01

    Full Text Available Aging is increasingly regarded as an independent risk factor for development of cardiovascular diseases such as atherosclerosis and hypertension and their complications (e.g. MI and Stroke. It is well known that vascular disease evolve over decades with progressive accumulation of cellular and extracellular materials and many inflammatory processes. Metabolic syndrome, obesity and diabetes are conventionally recognized as risk factors for development of coronary vascular disease (CVD. These conditions are known to accelerate ageing process in general and vascular ageing in particular. Adverse events during intrauterine life may programme organ growth and favour disease later in life, popularly known as, ′Barker′s Hypothesis′. The notion of fetal programming implies that during critical periods of prenatal growth, changes in the hormonal and nutritional milieu of the conceptus may alter the full expression of the fetal genome, leading to permanent effects on a range of physiological.

  4. Imaging after vascular gene therapy

    International Nuclear Information System (INIS)

    Manninen, Hannu I.; Yang, Xiaoming

    2005-01-01

    Targets for cardiovascular gene therapy currently include limiting restenosis after balloon angioplasty and stent placement, inhibiting vein bypass graft intimal hyperplasia/stenosis, therapeutic angiogenesis for cardiac and lower-limb ischemia, and prevention of thrombus formation. While catheter angiography is still standard method to follow-up vascular gene transfer, other modern imaging techniques, especially intravascular ultrasound (IVUS), magnetic resonance (MR), and positron emission tomography (PET) imaging provide complementary information about the therapeutic effect of vascular gene transfer in humans. Although molecular imaging of therapeutic gene expression in the vasculatures is still in its technical development phase, it has already offered basic medical science an extremely useful in vivo evaluation tool for non- or minimally invasive imaging of vascular gene therapy

  5. Vascular Gene Expression: A Hypothesis

    Directory of Open Access Journals (Sweden)

    Angélica Concepción eMartínez-Navarro

    2013-07-01

    Full Text Available The phloem is the conduit through which photoassimilates are distributed from autotrophic to heterotrophic tissues and is involved in the distribution of signaling molecules that coordinate plant growth and responses to the environment. Phloem function depends on the coordinate expression of a large array of genes. We have previously identified conserved motifs in upstream regions of the Arabidopsis genes, encoding the homologs of pumpkin phloem sap mRNAs, displaying expression in vascular tissues. This tissue-specific expression in Arabidopsis is predicted by the overrepresentation of GA/CT-rich motifs in gene promoters. In this work we have searched for common motifs in upstream regions of the homologous genes from plants considered to possess a primitive vascular tissue (a lycophyte, as well as from others that lack a true vascular tissue (a bryophyte, and finally from chlorophytes. Both lycophyte and bryophyte display motifs similar to those found in Arabidopsis with a significantly low E-value, while the chlorophytes showed either a different conserved motif or no conserved motif at all. These results suggest that these same genes are expressed coordinately in non- vascular plants; this coordinate expression may have been one of the prerequisites for the development of conducting tissues in plants. We have also analyzed the phylogeny of conserved proteins that may be involved in phloem function and development. The presence of CmPP16, APL, FT and YDA in chlorophytes suggests the recruitment of ancient regulatory networks for the development of the vascular tissue during evolution while OPS is a novel protein specific to vascular plants.

  6. [Vascular Calcification - Pathological Mechanism and Clinical Application - . Role of vascular smooth muscle cells in vascular calcification].

    Science.gov (United States)

    Kurabayashi, Masahiko

    2015-05-01

    Vascular calcification is commonly seen with aging, chronic kidney disese (CKD), diabetes, and atherosclerosis, and is closely associated with cardiovascular morbidity and mortality. Vascular calcification has long been regarded as the final stage of degeneration and necrosis of arterial wall and a passive, unregulated process. However, it is now known to be an active and tightly regulated process involved with phenotypic transition of vascular smooth muscle cells (VSMC) that resembles bone mineralization. Briefly, calcium deposits of atherosclerotic plaque consist of hydroxyapatite and may appear identical to fully formed lamellar bone. By using a genetic fate mapping strategy, VSMC of the vascular media give rise to the majority of the osteochondrogenic precursor- and chondrocyte-like cells observed in the calcified arterial media of MGP (- / -) mice. Osteogenic differentiation of VSMC is characterized by the expression of bone-related molecules including bone morphogenetic protein (BMP) -2, Msx2 and osteopontin, which are produced by osteoblasts and chondrocytes. Our recent findings are that (i) Runx2 and Notch1 induce osteogenic differentiation, and (ii) advanced glycation end-product (AGE) /receptor for AGE (RAGE) and palmitic acid promote osteogenic differentiation of VSMC. To understand of the molecular mechanisms of vascular calcification is now under intensive research area.

  7. Vascular malforma- tions part 1 — normal and abnormal vascular ...

    African Journals Online (AJOL)

    Enrique

    to form the primitive vascular plexus. Angiogenesis is the formation of new vessels by sprouting or splitting of ... The differentiation of primitive vessels into arteries, veins or capillaries is determined by flow patterns .... identify, but it is probable that as time progresses further specific genetic defects related to the development ...

  8. Genetic Regulation of Vascular Development: Building the Zebrafish Vascular Tree

    NARCIS (Netherlands)

    R.L.J.M. Herpers (Robert)

    2010-01-01

    textabstractThe extensive networks of blood and lymphatic vessels within the vertebrate body are essential for the transport and delivery of fluids, gases, macromolecules and cells, and play important roles in facilitating immune responses. The development of the vascular tree requires a highly

  9. Accommodation: The role of the external muscles of the eye: A consideration of refractive errors in relation to extraocular malfunction.

    Science.gov (United States)

    Hargrave, B K

    2014-11-01

    Speculation as to optical malfunction has led to dissatisfaction with the theory that the lens is the sole agent in accommodation and to the suggestion that other parts of the eye are also conjointly involved. Around half-a-century ago, Robert Brooks Simpkins suggested that the mechanical features of the human eye were precisely such as to allow for a lengthening of the globe when the eye accommodated. Simpkins was not an optical man but his theory is both imaginative and comprehensive and deserves consideration. It is submitted here that accommodation is in fact a twofold process, and that although involving the lens, is achieved primarily by means of a give - and - take interplay between adducting and abducting external muscles, whereby an elongation of the eyeball is brought about by a stretching of the delicate elastic fibres immediately behind the cornea. The three muscles responsible for convergence (superior, internal and inferior recti) all pull from in front backwards, while of the three abductors (external rectus and the two obliques) the obliques pull from behind forwards, allowing for an easy elongation as the eye turns inwards and a return to its original length as the abducting muscles regain their former tension, returning the eye to distance vision. In refractive errors, the altered length of the eyeball disturbs the harmonious give - and - take relationship between adductors and abductors. Such stresses are likely to be perpetuated and the error exacerbated. Speculation is not directed towards a search for a possible cause of the muscular imbalance, since none is suspected. Muscles not used rapidly lose tone, as evidenced after removal of a limb from plaster. Early attention to the need for restorative exercise is essential and results usually impressive. If flexibility of the external muscles of the eyes is essential for continuing good sight, presbyopia can be avoided and with it the supposed necessity of glasses in middle life. Early attention

  10. Vascular access surveillance: case study of a false paradigm.

    Science.gov (United States)

    Paulson, William D; Moist, Louise; Lok, Charmaine E

    2013-01-01

    The hemodialysis vascular access surveillance controversy provides a case study of how enthusiasm for a new test or treatment can lead to adoption of a false paradigm. Paradigms are the beliefs and assumptions shared by those in a field of knowledge, and are commonly included in clinical practice guidelines. The guidelines of the National Kidney Foundation Kidney Disease Outcomes Quality Initiative recommend that arteriovenous vascular accesses undergo routine surveillance for detection and correction of stenosis. This recommendation is based on the paradigm that surveillance of access blood flow or dialysis venous pressure combined with correction of stenosis improves access outcomes. However, the quality of evidence that supports this paradigm has been widely criticized. We tested the validity of the surveillance paradigm by applying World Health Organization (WHO) criteria for evaluating screening tests to a literature review of published vascular access studies. These criteria include four components: undesired condition, screening test, intervention, and desired outcome. The WHO criteria show that surveillance as currently practiced fails all four components and provides little or no significant benefit, suggesting that surveillance is a false paradigm. Once a paradigm is established, however, challenges to its validity are usually resisted even as new evidence indicates the paradigm is not valid. Thus, it is paramount to apply rigorous criteria when developing guidelines. Regulators may help promote needed changes in paradigms when cost and safety considerations coincide. © 2013 Wiley Periodicals, Inc.

  11. [Vascular access guidelines for hemodialysis].

    Science.gov (United States)

    Rodríguez Hernández, J A; González Parra, E; Julián Gutiérrez, J M; Segarra Medrano, A; Almirante, B; Martínez, M T; Arrieta, J; Fernández Rivera, C; Galera, A; Gallego Beuter, J; Górriz, J L; Herrero, J A; López Menchero, R; Ochando, A; Pérez Bañasco, V; Polo, J R; Pueyo, J; Ruiz, Camps I; Segura Iglesias, R

    2005-01-01

    Quality of vascular access (VA) has a remarkable influence in hemodialysis patients outcomes. Dysfunction of VA represents a capital cause of morbi-mortality of these patients as well an increase in economical. Spanish Society of Neprhology, aware of the problem, has decided to carry out a revision of the issue with the aim of providing help in comprehensión and treatment related with VA problems, and achieving an homogenization of practices in three mayor aspects: to increase arteriovenous fistula utilization as first vascular access, to increment vascular access monitoring practice and rationalise central catheters use. We present a consensus document elaborated by a multidisciplinar group composed by nephrologists, vascular surgeons, interventional radiologysts, infectious diseases specialists and nephrological nurses. Along six chapters that cover patient education, creation of VA, care, monitoring, complications and central catheters, we present the state of the art and propose guidelines for the best practice, according different evidence based degrees, with the intention to provide help at the professionals in order to make aproppiate decissions. Several quality standars are also included.

  12. Image Quality in Vascular Radiology

    International Nuclear Information System (INIS)

    Vanhavere, F.; Struelens, L.

    2005-01-01

    In vascular radiology, the radiologists use the radiological image to diagnose or treat a specific vascular structure. From literature, we know that related doses are high and that large dose variability exists between different hospitals. The application of the optimization principle is therefore necessary and is obliged by the new legislation. So far, very little fieldwork has been performed and no practical instructions are available to do the necessary work. It's indisputable that obtaining quantitative data is of great interest for optimization purposes. In order to gain insight into these doses and the possible measures for dose reduction, we performed a comparative study in 7 hospitals. Patient doses will be measured and calculated for specific procedures in vascular radiology and evaluated against their most influencing parameters. In view of optimization purposes, a protocol for dose audit will be set-up. From the results and conclusions in this study, experimentally based guidelines will be proposed, in order to improve clinical practice in vascular radiology

  13. Vascular aspects of multiple sclerosis

    NARCIS (Netherlands)

    D'haeseleer, Miguel; Cambron, Melissa; Vanopdenbosch, Ludo; De Keyser, Jacques

    Three types of vascular dysfunction have been described in multiple sclerosis (MS). First, findings from epidemiological studies suggest that patients with MS have a higher risk for ischaemic stroke than people who do not have MS. The underlying mechanism is unknown, but might involve endothelial

  14. Correction of Neonatal Hypovolemia

    Directory of Open Access Journals (Sweden)

    V. V. Moskalev

    2007-01-01

    Full Text Available Objective: to evaluate the efficiency of hydroxyethyl starch solution (6% refortane, Berlin-Chemie versus fresh frozen plasma used to correct neonatal hypovolemia.Materials and methods. In 12 neonatal infants with hypoco-agulation, hypovolemia was corrected with fresh frozen plasma (10 ml/kg body weight. In 13 neonates, it was corrected with 6% refortane infusion in a dose of 10 ml/kg. Doppler echocardiography was used to study central hemodynamic parameters and Doppler study was employed to examine regional blood flow in the anterior cerebral and renal arteries.Results. Infusion of 6% refortane and fresh frozen plasma at a rate of 10 ml/hour during an hour was found to normalize the parameters of central hemodynamics and regional blood flow.Conclusion. Comparative analysis of the findings suggests that 6% refortane is the drug of choice in correcting neonatal hypovolemia. Fresh frozen plasma should be infused in hemostatic disorders. 

  15. Corrective Jaw Surgery

    Medline Plus

    Full Text Available ... surgery. It is important to understand that your treatment, which will probably include orthodontics before and after ... to realistically estimate the time required for your treatment. Correction of Common Dentofacial Deformities ​ ​ The information provided ...

  16. Corrective Jaw Surgery

    Medline Plus

    Full Text Available ... misalignment of jaws and teeth. Surgery can improve chewing, speaking and breathing. While the patient's appearance may ... indicate the need for corrective jaw surgery: Difficulty chewing, or biting food Difficulty swallowing Chronic jaw or ...

  17. Corrective Jaw Surgery

    Medline Plus

    Full Text Available ... It can also invite bacteria that lead to gum disease. Click here to find out more. Who We ... It can also invite bacteria that lead to gum disease. Click here to find out more. Corrective Jaw ...

  18. Corrective Jaw Surgery

    Medline Plus

    Full Text Available ... is performed by an oral and maxillofacial surgeon (OMS) to correct a wide range of minor and ... when sleeping, including snoring) Your dentist, orthodontist and OMS will work together to determine whether you are ...

  19. ICT: isotope correction toolbox.

    Science.gov (United States)

    Jungreuthmayer, Christian; Neubauer, Stefan; Mairinger, Teresa; Zanghellini, Jürgen; Hann, Stephan

    2016-01-01

    Isotope tracer experiments are an invaluable technique to analyze and study the metabolism of biological systems. However, isotope labeling experiments are often affected by naturally abundant isotopes especially in cases where mass spectrometric methods make use of derivatization. The correction of these additive interferences--in particular for complex isotopic systems--is numerically challenging and still an emerging field of research. When positional information is generated via collision-induced dissociation, even more complex calculations for isotopic interference correction are necessary. So far, no freely available tools can handle tandem mass spectrometry data. We present isotope correction toolbox, a program that corrects tandem mass isotopomer data from tandem mass spectrometry experiments. Isotope correction toolbox is written in the multi-platform programming language Perl and, therefore, can be used on all commonly available computer platforms. Source code and documentation can be freely obtained under the Artistic License or the GNU General Public License from: https://github.com/jungreuc/isotope_correction_toolbox/ {christian.jungreuthmayer@boku.ac.at,juergen.zanghellini@boku.ac.at} Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. Design Approaches to Myocardial and Vascular Tissue Engineering.

    Science.gov (United States)

    Akintewe, Olukemi O; Roberts, Erin G; Rim, Nae-Gyune; Ferguson, Michael A H; Wong, Joyce Y

    2017-06-21

    Engineered tissues represent an increasingly promising therapeutic approach for correcting structural defects and promoting tissue regeneration in cardiovascular diseases. One of the challenges associated with this approach has been the necessity for the replacement tissue to promote sufficient vascularization to maintain functionality after implantation. This review highlights a number of promising prevascularization design approaches for introducing vasculature into engineered tissues. Although we focus on encouraging blood vessel formation within myocardial implants, we also discuss techniques developed for other tissues that could eventually become relevant to engineered cardiac tissues. Because the ultimate solution to engineered tissue vascularization will require collaboration between wide-ranging disciplines such as developmental biology, tissue engineering, and computational modeling, we explore contributions from each field.

  1. Subclinical hypothyroidism after vascular complicated pregnancy

    NARCIS (Netherlands)

    Zanden, M. van der; Hop-de Groot, R.J.; Sweep, F.C.; Ross, H.A.; Heijer, M. den; Spaanderman, M.E.A.

    2013-01-01

    OBJECTIVE: Women with a history of vascular complicated pregnancy are at risk for developing remote cardiovascular disease. It is associated with underlying cardiovascular risk factors both jeopardizing trophoblast and vascular function. Subclinical hypothyroidism may relate to both conditions.

  2. Pediatric central nervous system vascular malformations

    International Nuclear Information System (INIS)

    Burch, Ezra A.; Orbach, Darren B.

    2015-01-01

    Pediatric central nervous system (CNS) vascular anomalies include lesions found only in the pediatric population and also the full gamut of vascular lesions found in adults. Pediatric-specific lesions discussed here include infantile hemangioma, vein of Galen malformation and dural sinus malformation. Some CNS vascular lesions that occur in adults, such as arteriovenous malformation, have somewhat distinct manifestations in children, and those are also discussed. Additionally, children with CNS vascular malformations often have associated broader vascular conditions, e.g., PHACES (posterior fossa anomalies, hemangioma, arterial anomalies, cardiac anomalies, eye anomalies and sternal anomalies), hereditary hemorrhagic telangiectasia, and capillary malformation-arteriovenous malformation syndrome (related to the RASA1 mutation). The treatment of pediatric CNS vascular malformations has greatly benefited from advances in endovascular therapy, including technical advances in adult interventional neuroradiology. Dramatic advances in therapy are expected to stem from increased understanding of the genetics and vascular biology that underlie pediatric CNS vascular malformations. (orig.)

  3. Pediatric central nervous system vascular malformations

    Energy Technology Data Exchange (ETDEWEB)

    Burch, Ezra A. [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); Orbach, Darren B. [Boston Children' s Hospital, Neurointerventional Radiology, Boston, MA (United States)

    2015-09-15

    Pediatric central nervous system (CNS) vascular anomalies include lesions found only in the pediatric population and also the full gamut of vascular lesions found in adults. Pediatric-specific lesions discussed here include infantile hemangioma, vein of Galen malformation and dural sinus malformation. Some CNS vascular lesions that occur in adults, such as arteriovenous malformation, have somewhat distinct manifestations in children, and those are also discussed. Additionally, children with CNS vascular malformations often have associated broader vascular conditions, e.g., PHACES (posterior fossa anomalies, hemangioma, arterial anomalies, cardiac anomalies, eye anomalies and sternal anomalies), hereditary hemorrhagic telangiectasia, and capillary malformation-arteriovenous malformation syndrome (related to the RASA1 mutation). The treatment of pediatric CNS vascular malformations has greatly benefited from advances in endovascular therapy, including technical advances in adult interventional neuroradiology. Dramatic advances in therapy are expected to stem from increased understanding of the genetics and vascular biology that underlie pediatric CNS vascular malformations. (orig.)

  4. ESRD QIP - Vascular Access - Payment Year 2018

    Data.gov (United States)

    U.S. Department of Health & Human Services — This dataset includes facility details, performance rates, vascular access topic measure score, and the state and national average measure scores for the vascular...

  5. Investigation of reactor incident reports with regard to human malfunctions as far as these had an effect on the incident history

    International Nuclear Information System (INIS)

    Hoffmann, E.

    1984-01-01

    The study has the aim to examine by means of a human failure analysis the operation of a nuclear power plant with regard to its weak points, in order to deduce by this starting-points for operational improvements. Contrary to most studies published on this subject and which are often based on free-hand hypotheses and plausibility studies here, the experience gained in the operation is systematically examined with regard to human malfunction and their deeper causes, i.e. on the experience which was founded on some 1,000 collected reports on incidents. (orig./GL) [de

  6. Geological Corrections in Gravimetry

    Science.gov (United States)

    Mikuška, J.; Marušiak, I.

    2015-12-01

    Applying corrections for the known geology to gravity data can be traced back into the first quarter of the 20th century. Later on, mostly in areas with sedimentary cover, at local and regional scales, the correction known as gravity stripping has been in use since the mid 1960s, provided that there was enough geological information. Stripping at regional to global scales became possible after releasing the CRUST 2.0 and later CRUST 1.0 models in the years 2000 and 2013, respectively. Especially the later model provides quite a new view on the relevant geometries and on the topographic and crustal densities as well as on the crust/mantle density contrast. Thus, the isostatic corrections, which have been often used in the past, can now be replaced by procedures working with an independent information interpreted primarily from seismic studies. We have developed software for performing geological corrections in space domain, based on a-priori geometry and density grids which can be of either rectangular or spherical/ellipsoidal types with cells of the shapes of rectangles, tesseroids or triangles. It enables us to calculate the required gravitational effects not only in the form of surface maps or profiles but, for instance, also along vertical lines, which can shed some additional light on the nature of the geological correction. The software can work at a variety of scales and considers the input information to an optional distance from the calculation point up to the antipodes. Our main objective is to treat geological correction as an alternative to accounting for the topography with varying densities since the bottoms of the topographic masses, namely the geoid or ellipsoid, generally do not represent geological boundaries. As well we would like to call attention to the possible distortions of the corrected gravity anomalies. This work was supported by the Slovak Research and Development Agency under the contract APVV-0827-12.

  7. Vascular neurocognitive disorders and the vascular risk factors

    Directory of Open Access Journals (Sweden)

    Carmen V. Albu

    2018-04-01

    Full Text Available Dementias are clinical neurodegenerative diseases characterized by permanent and progressive transformation of cognitive functions such as memory, learning capacity, attention, thinking, language, passing judgments, calculation or orientation. Dementias represent a relatively frequent pathology, encountered at about 10% of the population of 65-year olds and 20% of the population of 80-year olds. This review presents the main etiological forms of dementia, which include Alzheimer form of dementia, vascular dementia, dementia associated with alpha-synucleionopathies, and mixed forms. Regarding vascular dementia, the risk factors are similar to those for an ischemic or hemorrhagic cerebrovascular accident: arterial hypertension, diabetes mellitus, dyslipidemia, smoking, obesity, age, alcohol consumption, cerebral atherosclerosis/ arteriosclerosis. Several studies show that efficient management of the vascular risk factors can prevent the expression and/ or progression of dementia. Thus, lifestyle changes such as stress reduction, regular physical exercise, decreasing dietary fat, multivitamin supplementation, adequate control of blood pressure and serum cholesterol, and social integration and mental stimulation in the elderly population are important factors in preventing or limiting the symptoms of dementia, a disease with significant individual, social, and economic implications.

  8. [The added value of a structured evaluation of patients with vascular disease

    NARCIS (Netherlands)

    Bredie, S.J.H.; Wollersheim, H.C.H.; Lenders, J.W.M.; Stalenhoef, A.F.H.

    2002-01-01

    In 3 patients, 2 women aged 21 and 34 years and a man aged 56 years, with complaints related to wide-ranging and extensive vascular conditions, an organ-specific diagnostic approach and treatment did not lead to the correct diagnosis of the underlying clinical condition. Hereafter a structured,

  9. MONITORING OF ATOMOXETINE EFFICIENCY IN CORRECTION OF THE SCHOOL DYSADAPTATION

    Directory of Open Access Journals (Sweden)

    O.A. Sobokar'

    2008-01-01

    Full Text Available In the given article, the authors highlight the results of the research into the school dysadaptation of the children, who have undergone intracranial vascular injuries in neonatal period. Researchers also studied the efficiency of atomoxetine for the correction of this pathology. The authors demonstrated both its high efficiency and good tolerance and safety in the event of the attention deficiency and hyperactivity disorder.Key words: school dysadaptation, attention_deficit and hyper activity disorder, treatment, children.

  10. Robust Active Label Correction

    DEFF Research Database (Denmark)

    Kremer, Jan; Sha, Fei; Igel, Christian

    2018-01-01

    for the noisy data lead to different active label correction algorithms. If loss functions consider the label noise rates, these rates are estimated during learning, where importance weighting compensates for the sampling bias. We show empirically that viewing the true label as a latent variable and computing......Active label correction addresses the problem of learning from input data for which noisy labels are available (e.g., from imprecise measurements or crowd-sourcing) and each true label can be obtained at a significant cost (e.g., through additional measurements or human experts). To minimize......). To select labels for correction, we adopt the active learning strategy of maximizing the expected model change. We consider the change in regularized empirical risk functionals that use different pointwise loss functions for patterns with noisy and true labels, respectively. Different loss functions...

  11. Generalised Batho correction factor

    International Nuclear Information System (INIS)

    Siddon, R.L.

    1984-01-01

    There are various approximate algorithms available to calculate the radiation dose in the presence of a heterogeneous medium. The Webb and Fox product over layers formulation of the generalised Batho correction factor requires determination of the number of layers and the layer densities for each ray path. It has been shown that the Webb and Fox expression is inefficient for the heterogeneous medium which is expressed as regions of inhomogeneity rather than layers. The inefficiency of the layer formulation is identified as the repeated problem of determining for each ray path which inhomogeneity region corresponds to a particular layer. It has been shown that the formulation of the Batho correction factor as a product over inhomogeneity regions avoids that topological problem entirely. The formulation in terms of a product over regions simplifies the computer code and reduces the time required to calculate the Batho correction factor for the general heterogeneous medium. (U.K.)

  12. THE SECONDARY EXTINCTION CORRECTION

    Energy Technology Data Exchange (ETDEWEB)

    Zachariasen, W. H.

    1963-03-15

    It is shown that Darwin's formula for the secondary extinction correction, which has been universally accepted and extensively used, contains an appreciable error in the x-ray diffraction case. The correct formula is derived. As a first order correction for secondary extinction, Darwin showed that one should use an effective absorption coefficient mu + gQ where an unpolarized incident beam is presumed. The new derivation shows that the effective absorption coefficient is mu + 2gQ(1 + cos/sup 4/2 theta )/(1 plus or minus cos/sup 2/2 theta )/s up 2/, which gives mu + gQ at theta =0 deg and theta = 90 deg , but mu + 2gQ at theta = 45 deg . Darwin's theory remains valid when applied to neutron diffraction. (auth)

  13. Near-infrared spectroscopy for detection of vascular compromise in paediatric supracondylar fractures

    International Nuclear Information System (INIS)

    Skowno, Justin J; De Lima, Jonathan; Quick, Tom J; Carpenter, Eleanor C; Gibbons, Paul J; Little, David G

    2014-01-01

    Children suffering supracondylar fractures of the humerus are at risk of vascular compromise, which is currently assessed clinically, although other modalities such as angiography, pulse oximetry, Doppler ultrasound and magnetic resonance angiography have been used. We sought to ascertain whether tissue haemoglobin oxygenation (StO 2 ) measurement could distinguish between patients with and without clinical vascular compromise following supracondylar fractures of the humerus. We prospectively observed StO 2  using near-infrared spectroscopy in 29 paediatric patients with supracondylar fractures requiring operative manipulation. The injured and uninjured volar forearm compartments were monitored immediately before and after fracture reduction. The relationship between StO 2  in the injured and uninjured limb, and the presence of pre-operative vascular compromise was assessed. Seven out of 29 children presented with vascular compromise. Patients with clinical vascular compromise had significantly lower pre-reduction StO 2  (63.5% ± 15%, mean ± standard deviation), compared to those without compromise (80.9% ± 10%). StO 2  normalized following surgery in all children with vascular compromise. These improvements in muscle StO 2  were associated, in all patients, with the clinical return of pulses and resolution of neurological symptoms if present. StO 2  monitoring can identify patients with clinical vascular compromise, can identify the return of adequate perfusion following operative correction of supracondylar fractures, and may be a useful adjunct to clinical assessment. (paper)

  14. Vascularized osseous graft for scaphoid

    International Nuclear Information System (INIS)

    Mendez Daza, Carlos Hernan; Mathoulin, Cristophe

    2004-01-01

    The most commonly used technique for treatment of pseudo-arthrosis of the scaphoid is osteo-synthesis with Kirschnet wires and cortical sponge grafts. Results reported by different teams using this procedure show no more than 90% osseous consolidation, especially in cases where vascularisation of the proximal fragment of the scaphoid is compromised. Here we present a series of ten cases of pseudo-arthrosis of the scaphoid, treated using a new surgical technique involving a vascularized osseous graft of the distal radius. Using this procedure we obtained 100% consolidation, with no complications either during the procedure or immediately post-operatively. Patients returned to work in week 15 on average. In 4 cases we observed discomfort in the area of the scar, which was successfully treated using local cortisone injection. The results obtained are very similar to those seen in the literature on the different techniques for vascularized osseous grafts for pseudo-arthrosis of the scaphoid

  15. [Menopause: Hypertension and vascular disease].

    Science.gov (United States)

    Zilberman, J M

    Hypertension is the main cardiovascular risk factor affecting 25% of women. Hormone changes and hypertension after menopause may lead to higher target organ damage and cardiovascular disease such as increased arterial stiffness, coronary diseases, chronic heart failure and stroke. The physiopathological mechanisms involved in the development of hypertension and cardiovascular diseases in menopausal women are controversial. There are pharmacokinetic and pharmacodynamic differences in both sexes, the women have more coughing when using the converting-enzyme inhibitors, more cramps when using thiazide diuretics and more oedema in the inferior limbs when using calcium antagonists. The aim of this review is to analyse possible physiopathological mechanisms involved in hypertension after menopause and to gain a better understanding of the biological effects mediated by vascular ageing in women when the level of oestrogen protective effect decreases over the vascular system. Copyright © 2017 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Vascular diagnostics for Raynaud's phenomenon

    Directory of Open Access Journals (Sweden)

    Dinsdale G

    2014-10-01

    Full Text Available Graham Dinsdale, Ariane L Herrick Centre for Musculoskeletal Research, Institute of Inflammation and Repair, Salford Royal NHS Foundation Trust, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK Abstract: Raynaud's phenomenon (RP is common, and in most patients is primary (idiopathic when due to reversible vasospasm and does not progress to irreversible tissue injury. However, in those patients for whom RP is secondary to an underlying disease (eg, systemic sclerosis or atherosclerosis, progression to digital ulceration or critical ischemia can occur. Therefore, the key question for the clinician is “Why does this patient have RP?” Vascular diagnostics play a key role in answering this. In this review, we firstly discuss the different vascular investigations relevant to clinical practice: nail fold capillaroscopy (including the different methodologies for examining the nail fold capillaries, and the role of capillaroscopy in helping to differentiate between primary and systemic sclerosis-related RP, thermography (available in specialist centers, and evaluation of large vessel disease (for example, due to atherosclerosis. We then discuss research tools, mainly laser Doppler methods, including laser Doppler imaging and laser speckle contrast imaging. These are commercially available as complete imaging systems and are (relatively easy to use. The main current goal in vascular imaging research is to validate these novel state-of-the-art techniques as outcome measures of digital vascular disease, and then apply them in early and later phase studies of new treatment approaches, thus facilitating drug development programs. Keywords: Raynaud's phenomenon, systemic sclerosis, nail fold capillaroscopy, thermography, laser Doppler, angiography

  17. Vascular complications after the treatment of carcinoma of the cervix

    International Nuclear Information System (INIS)

    Cormier, J.M.; Laurian, C.

    1980-01-01

    Vascular complications after this treatment are rare. Artery stenosis or occlusions, more often iliac, are well recognized complications of postoperative radiotherapy. These segmental lesions, sometimes, are pathological lesions similar to arteriosclerotic changes. These lesions may be corrected later on after the treatment of carcinoma of the cervix. The venous complications often present later and tall within the context of post thrombotic syndrome. Conservative treatment is indicated alone. A well recognized complication, lymphedema is usually mild; a superimposed iliofemoral thrombophlebitis often may be suspected [fr

  18. Bryant J. correction formula

    International Nuclear Information System (INIS)

    Tejera R, A.; Cortes P, A.; Becerril V, A.

    1990-03-01

    For the practical application of the method proposed by J. Bryant, the authors carried out a series of small corrections, related with the bottom, the dead time of the detectors and channels, with the resolution time of the coincidences, with the accidental coincidences, with the decay scheme and with the gamma efficiency of the beta detector beta and the beta efficiency beta of the gamma detector. The calculation of the correction formula is presented in the development of the present report, being presented 25 combinations of the probability of the first existent state at once of one disintegration and the second state at once of the following disintegration. (Author)

  19. Model Correction Factor Method

    DEFF Research Database (Denmark)

    Christensen, Claus; Randrup-Thomsen, Søren; Morsing Johannesen, Johannes

    1997-01-01

    The model correction factor method is proposed as an alternative to traditional polynomial based response surface techniques in structural reliability considering a computationally time consuming limit state procedure as a 'black box'. The class of polynomial functions is replaced by a limit...... of the model correction factor method, is that in simpler form not using gradient information on the original limit state function or only using this information once, a drastic reduction of the number of limit state evaluation is obtained together with good approximations on the reliability. Methods...

  20. Investigation on cause of malfunction of wide range monitor (WRM) in high temperature engineering test reactor (HTTR). Sample tests and destructive tests

    International Nuclear Information System (INIS)

    Shinohara, Masanori; Saito, Kenji; Haga, Hiroyuki; Sasaki, Shinji; Katsuyama, Kozo; Motegi, Toshihiro; Takada, Kiyoshi; Higashimura, Keisuke; Fujii, Junichi; Ukai, Takayuki; Moriguchi, Yusuke

    2012-11-01

    An event, in which one of WRMs were disabled to detect the neutron flux in the reactor core, occurred during the period of reactor shut down of HTTR in March, 2010. The actual life time of WRM was unexpectedly shorter than the past developed life time. Investigation of the cause of the outage of WRM toward the recovery of the life time up to the past developed life is one of the issues to develop the technology basis of High Temperature Gas cooled Reactor (HTGR). Then, two experimental investigations were carried out to reveal the cause of the malfunction by specifying the damaged part causing the event in the WRM. One is an experiment using a mock-up sample test which strength degradation at assembly process and heat cycle to specify the damaged part in the WRM. The other is a destructive test in Fuels Monitoring Facility (FMF) to specify the damaged part in the WRM. This report summarized the results of the destructive test and the experimental investigation using the mock-up to reveal the cause of malfunction of WRM. (author)

  1. The BK(Ca) channels deficiency as a possible reason for radiation-induced vascular hypercontractility.

    Science.gov (United States)

    Kyrychenko, Sergii; Tishkin, Sergey; Dosenko, Victor; Ivanova, Irina; Novokhatska, Tatiana; Soloviev, Anatoly

    2012-01-01

    It is likely that large-conductance Ca²⁺-activated K⁺ (BK(Ca)) channels channelopathy tightly involved in vascular malfunctions and arterial hypertension development. In the present study, we compared the results of siRNAs-induced α-BK(Ca) gene silencing and vascular abnormalities produced by whole-body ionized irradiation in rats. The experimental design comprised RT-PCR and patch clamp technique, thoracic aorta smooth muscle (SM) contractile recordings and arterial blood pressure (BP) measurements on the 30th day after whole body irradiation (6Gy) and following siRNAs KCNMA1 gene silencing in vivo. The expression profile of BK(Ca) mRNA transcripts in SM was significantly decreased in siRNAs-treated rats in a manner similar to irradiated SM. In contrast, the mRNA levels of K(v) and K(ATP) were significantly increased while L-type calcium channels mRNA transcripts demonstrated tendency to increment. The SMCs obtained from irradiated animals and after KCNMA1 gene silencing showed a significant decrease in total K⁺ current density amplitude. Paxilline (500 nM)-sensitive components of outward current were significantly decreased in both irradiated and gene silencing SMCs. KCNMA1 gene silencing increased SM sensitivity to norepinephrine while Ach-induced relaxation had decreased. The silencing of KCNMA1 had no significant effect on BP while radiation produced sustained arterial hypertension. Therefore, radiation alters the form and function of the BK(Ca) channel and this type of channelopathy may contribute to related vascular abnormalities. Nevertheless, it is unlikely that BK(Ca) can operate as a crucial factor for radiation-induced arterial hypertension. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Attenuation correction for SPECT

    International Nuclear Information System (INIS)

    Hosoba, Minoru

    1986-01-01

    Attenuation correction is required for the reconstruction of a quantitative SPECT image. A new method for detecting body contours, which are important for the correction of tissue attenuation, is presented. The effect of body contours, detected by the newly developed method, on the reconstructed images was evaluated using various techniques for attenuation correction. The count rates in the specified region of interest in the phantom image by the Radial Post Correction (RPC) method, the Weighted Back Projection (WBP) method, Chang's method were strongly affected by the accuracy of the contours, as compared to those by Sorenson's method. To evaluate the effect of non-uniform attenuators on the cardiac SPECT, computer simulation experiments were performed using two types of models, the uniform attenuator model (UAM) and the non-uniform attenuator model (NUAM). The RPC method showed the lowest relative percent error (%ERROR) in UAM (11 %). However, 20 to 30 percent increase in %ERROR was observed for NUAM reconstructed with the RPC, WBP, and Chang's methods. Introducing an average attenuation coefficient (0.12/cm for Tc-99m and 0.14/cm for Tl-201) in the RPC method decreased %ERROR to the levels for UAM. Finally, a comparison between images, which were obtained by 180 deg and 360 deg scans and reconstructed from the RPC method, showed that the degree of the distortion of the contour of the simulated ventricles in the 180 deg scan was 15 % higher than that in the 360 deg scan. (Namekawa, K.)

  3. Text Induced Spelling Correction

    NARCIS (Netherlands)

    Reynaert, M.W.C.

    2004-01-01

    We present TISC, a language-independent and context-sensitive spelling checking and correction system designed to facilitate the automatic removal of non-word spelling errors in large corpora. Its lexicon is derived from a very large corpus of raw text, without supervision, and contains word

  4. Ballistic deficit correction

    International Nuclear Information System (INIS)

    Duchene, G.; Moszynski, M.; Curien, D.

    1991-01-01

    The EUROGAM data-acquisition has to handle a large number of events/s. Typical in-beam experiments using heavy-ion fusion reactions assume the production of about 50 000 compound nuclei per second deexciting via particle and γ-ray emissions. The very powerful γ-ray detection of EUROGAM is expected to produce high-fold event rates as large as 10 4 events/s. Such high count rates introduce, in a common dead time mode, large dead times for the whole system associated with the processing of the pulse, its digitization and its readout (from the preamplifier pulse up to the readout of the information). In order to minimize the dead time the shaping time constant τ, usually about 3 μs for large volume Ge detectors has to be reduced. Smaller shaping times, however, will adversely affect the energy resolution due to ballistic deficit. One possible solution is to operate the linear amplifier, with a somewhat smaller shaping time constant (in the present case we choose τ = 1.5 μs), in combination with a ballistic deficit compensator. The ballistic deficit can be corrected in different ways using a Gated Integrator, a hardware correction or even a software correction. In this paper we present a comparative study of the software and hardware corrections as well as gated integration

  5. Correctness of concurrent processes

    NARCIS (Netherlands)

    E.R. Olderog (Ernst-Rüdiger)

    1989-01-01

    textabstractA new notion of correctness for concurrent processes is introduced and investigated. It is a relationship P sat S between process terms P built up from operators of CCS [Mi 80], CSP [Ho 85] and COSY [LTS 79] and logical formulas S specifying sets of finite communication sequences as in

  6. Error Correcting Codes -34 ...

    Indian Academy of Sciences (India)

    information and coding theory. A large scale relay computer had failed to deliver the expected results due to a hardware fault. Hamming, one of the active proponents of computer usage, was determined to find an efficient means by which computers could detect and correct their own faults. A mathematician by train-.

  7. Measured attenuation correction methods

    International Nuclear Information System (INIS)

    Ostertag, H.; Kuebler, W.K.; Doll, J.; Lorenz, W.J.

    1989-01-01

    Accurate attenuation correction is a prerequisite for the determination of exact local radioactivity concentrations in positron emission tomography. Attenuation correction factors range from 4-5 in brain studies to 50-100 in whole body measurements. This report gives an overview of the different methods of determining the attenuation correction factors by transmission measurements using an external positron emitting source. The long-lived generator nuclide 68 Ge/ 68 Ga is commonly used for this purpose. The additional patient dose from the transmission source is usually a small fraction of the dose due to the subsequent emission measurement. Ring-shaped transmission sources as well as rotating point or line sources are employed in modern positron tomographs. By masking a rotating line or point source, random and scattered events in the transmission scans can be effectively suppressed. The problems of measured attenuation correction are discussed: Transmission/emission mismatch, random and scattered event contamination, counting statistics, transmission/emission scatter compensation, transmission scan after administration of activity to the patient. By using a double masking technique simultaneous emission and transmission scans become feasible. (orig.)

  8. Corrective Jaw Surgery

    Medline Plus

    Full Text Available ... their surgery, orthognathic surgery is performed to correct functional problems. Jaw Surgery can have a dramatic effect on many aspects of life. Following are some of the conditions that may ... front, or side Facial injury Birth defects Receding lower jaw and ...

  9. Error Correcting Codes

    Indian Academy of Sciences (India)

    successful consumer products of all time - the Compact Disc. (CD) digital audio .... We can make ... only 2 t additional parity check symbols are required, to be able to correct t .... display information (contah'ling music related data and a table.

  10. Error Correcting Codes

    Indian Academy of Sciences (India)

    Science and Automation at ... the Reed-Solomon code contained 223 bytes of data, (a byte ... then you have a data storage system with error correction, that ..... practical codes, storing such a table is infeasible, as it is generally too large.

  11. Error Correcting Codes

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 3. Error Correcting Codes - Reed Solomon Codes. Priti Shankar. Series Article Volume 2 Issue 3 March ... Author Affiliations. Priti Shankar1. Department of Computer Science and Automation, Indian Institute of Science, Bangalore 560 012, India ...

  12. 10. Correctness of Programs

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 3; Issue 4. Algorithms - Correctness of Programs. R K Shyamasundar. Series Article Volume 3 ... Author Affiliations. R K Shyamasundar1. Computer Science Group, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, India.

  13. Improving Technology for Vascular Imaging

    Science.gov (United States)

    Rana, Raman

    Neuro-endovascular image guided interventions (Neuro-EIGIs) is a minimally invasive procedure that require micro catheters and endovascular devices be inserted into the vasculature via an incision near the femoral artery and guided under low dose fluoroscopy to the vasculature of the head and neck. However, the endovascular devices used for the purpose are of very small size (stents are of the order of 50mum to 100mum) and the success of these EIGIs depends a lot on the accurate placement of these devices. In order to accurately place these devices inside the patient, the interventionalist should be able to see them clearly. Hence, high resolution capabilities are of immense importance in neuro-EIGIs. The high-resolution detectors, MAF-CCD and MAF-CMOS, at the Toshiba Stroke and Vascular Research Center at the University at Buffalo are capable of presenting improved images for better patient care. Focal spot of an x-ray tube plays an important role in performance of these high resolution detectors. The finite size of the focal spot results into the blurriness around the edges of the image of the object resulting in reduced spatial resolution. Hence, knowledge of accurate size of the focal spot of the x-ray tube is very essential for the evaluation of the total system performance. Importance of magnification and image detector blur deconvolution was demonstrated to carry out the more accurate measurement of x-ray focal spot using a pinhole camera. A 30 micron pinhole was used to obtain the focal spot images using flat panel detector (FPD) and different source to image distances (SIDs) were used to achieve different magnifications (3.16, 2.66 and 2.16). These focal spot images were deconvolved with a 2-D modulation transfer function (MTF), obtained using noise response (NR) method, to remove the detector blur present in the images. Using these corrected images, the accurate size of all the three focal spots were obtained and it was also established that effect of

  14. Three-component hydraulic penile prosthesis malfunction due to penile fibrolipoma secondary to augmentative phalloplasty: A case report

    Directory of Open Access Journals (Sweden)

    Gabriele Antonini

    2016-01-01

    Full Text Available Fibrolipomas are an infrequent type of lipomas. We describe a case of a man suffering from subcutaneous penile fibrolipoma, who twelve months earlier has been submitted to augmentative phalloplasty due to aesthetic dysmorphophobia. The same patient three years earlier has been submitted to three-component hydraulic penile prostheses implantation due to erectile dysfunction. After six months from removing of the mass, the penile elongation and penile enlargement were stable, the prostheses were correctly functioning and the patient was satisfied with his sexual intercourse and life. The diagnostics and surgical characteristics of this case are reported.

  15. Scale-adaptive surface modeling of vascular structures

    Directory of Open Access Journals (Sweden)

    Ma Xin

    2010-11-01

    Full Text Available Abstract Background The effective geometric modeling of vascular structures is crucial for diagnosis, therapy planning and medical education. These applications require good balance with respect to surface smoothness, surface accuracy, triangle quality and surface size. Methods Our method first extracts the vascular boundary voxels from the segmentation result, and utilizes these voxels to build a three-dimensional (3D point cloud whose normal vectors are estimated via covariance analysis. Then a 3D implicit indicator function is computed from the oriented 3D point cloud by solving a Poisson equation. Finally the vessel surface is generated by a proposed adaptive polygonization algorithm for explicit 3D visualization. Results Experiments carried out on several typical vascular structures demonstrate that the presented method yields both a smooth morphologically correct and a topologically preserved two-manifold surface, which is scale-adaptive to the local curvature of the surface. Furthermore, the presented method produces fewer and better-shaped triangles with satisfactory surface quality and accuracy. Conclusions Compared to other state-of-the-art approaches, our method reaches good balance in terms of smoothness, accuracy, triangle quality and surface size. The vessel surfaces produced by our method are suitable for applications such as computational fluid dynamics simulations and real-time virtual interventional surgery.

  16. Ghrelin improves vascular autophagy in rats with vascular calcification.

    Science.gov (United States)

    Xu, Mingming; Liu, Lin; Song, Chenfang; Chen, Wei; Gui, Shuyan

    2017-06-15

    This study aimed to investigate whether ghrelin ameliorated vascular calcification (VC) through improving autophagy. VC model was induced by nicotine plus vitamin D 3 in rats and β-glycerophosphate in vascular smooth muscle cell (VSMC). Calcium deposition was detected by von Kossa staining or alizarin red S staining. ALP activity was also detected. Western blot was used to assess the protein expression. Ghrelin treatment attenuated the elevation of calcium deposition and ALP activity in VC model both in vivo and in vitro. Interesting, the protein levels of autophagy markers, LC3 and beclin1 were significantly upregulated by ghrelin in VC model. An autophagy inhibitor, 3-methyladenine blocks the ameliorative effect of ghrelin on VC. Furthermore, protein expressions of phosphate-AMPK were increased by ghrelin treatment both in calcified aorta and VSMC. The effect of ghrelin on autophagy induction and VC attenuation was prevented by AMPK inhibitor, compound C. Our results suggested that ghrelin improved autophagy through AMPK activation, which was resulted in VC amelioration. These data maybe throw light on prevention and therapy of VC. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. An Innovative Serious Game for the Detection and Rehabilitation of Oral-Facial Malfunction in Children: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Nuria Máximo-Bocanegra

    2017-01-01

    Full Text Available We present SONRIE, a serious game based on virtual reality and comprising four games which act as tests where children must perform gestures in order to progress through several screens (raising eyebrows, kissing, blowing, and smiling. The aims of this pilot study were to evaluate the overall acceptance of the game and the capacity for detecting anomalies in motor execution and, lastly, to establish motor control benchmarks in orofacial muscles. For this purpose, tests were performed in school settings with 96 typically developing children aged between five and seven years. Regarding the different games, in the kissing game, children were able to execute the correct movement at six years of age and a precise movement at the age of seven years. Blowing actions required more maturity, starting from the age of five and achievable by the age of six years. The smiling game was performed correctly among all ages evaluated. The percentage of children who mastered this gesture with both precision and speed was progressively greater reaching more than 75% of values above 100 for children aged seven years. SONRIE was accepted enthusiastically among the population under study. In the future, SONRIE could be used as a tool for detecting difficulties regarding self-control and for influencing performance and the ability to produce fine-tuned facial movements.

  18. Dynamic article: surgical anatomical planes for complete mesocolic excision and applied vascular anatomy of the right colon.

    Science.gov (United States)

    Açar, Halil İbrahim; Cömert, Ayhan; Avşar, Abdullah; Çelik, Safa; Kuzu, Mehmet Ayhan

    2014-10-01

    Lower local recurrence rates and better overall survival are associated with complete mesocolic excision with central vascular ligation for treatment of colon cancer. To accomplish this, surgeons need to pay special attention to the surgical anatomical planes and vascular anatomy of the colon. However, surgical education in this area has been neglected. The aim of this study is to define the correct surgical anatomical planes for complete mesocolic excision with central vascular ligation and to demonstrate the correct dissection technique for protecting anatomical structures. Macroscopic and microscopic surgical dissections were performed on 12 cadavers in the anatomy laboratory and on autopsy specimens. The dissections were recorded as video clips. Dissections were performed in accordance with the complete mesocolic excision technique on 10 male and 2 female cadavers. Vascular structures, autonomic nerves, and related fascias were shown. Within each step of the surgical procedure, important anatomical structures were displayed on still images captured from videos by animations. Three crucial steps for complete mesocolic excision with central vascular ligation are demonstrated on the cadavers: 1) full mobilization of the superior mesenteric root following the embryological planes between the visceral and the parietal fascias; 2) mobilization of the mesocolon from the duodenum and the pancreas and identification of vascular structures, especially the veins around the pancreas; and 3) central vascular ligation of the colonic vessels at their origin, taking into account the vascular variations within the mesocolonic vessels and the autonomic nerves around the superior mesenteric artery. The limitation of this study was the number of the cadavers used. Successful complete mesocolic excision with central vascular ligation depends on an accurate knowledge of the surgical anatomical planes and the vascular anatomy of the colon.

  19. Correction of refractive errors

    Directory of Open Access Journals (Sweden)

    Vladimir Pfeifer

    2005-10-01

    Full Text Available Background: Spectacles and contact lenses are the most frequently used, the safest and the cheapest way to correct refractive errors. The development of keratorefractive surgery has brought new opportunities for correction of refractive errors in patients who have the need to be less dependent of spectacles or contact lenses. Until recently, RK was the most commonly performed refractive procedure for nearsighted patients.Conclusions: The introduction of excimer laser in refractive surgery has given the new opportunities of remodelling the cornea. The laser energy can be delivered on the stromal surface like in PRK or deeper on the corneal stroma by means of lamellar surgery. In LASIK flap is created with microkeratome in LASEK with ethanol and in epi-LASIK the ultra thin flap is created mechanically.

  20. PS Booster Orbit Correction

    CERN Document Server

    Chanel, M; Rumolo, G; Tomás, R; CERN. Geneva. AB Department

    2008-01-01

    At the end of the 2007 run, orbit measurements were carried out in the 4 rings of the PS Booster (PSB) for different working points and beam energies. The aim of these measurements was to provide the necessary input data for a PSB realignment campaign during the 2007/2008 shutdown. Currently, only very few corrector magnets can be operated reliably in the PSB; therefore the orbit correction has to be achieved by displacing (horizontally and vertically) and/or tilting some of the defocusing quadrupoles (QDs). In this report we first describe the orbit measurements, followed by a detailed explanation of the orbit correction strategy. Results and conclusions are presented in the last section.

  1. Non-vascular surgical mediastinum

    International Nuclear Information System (INIS)

    Schiavon, S.; Trenaghi, P.; Nardini, S.; Pagan, V.

    1989-01-01

    A review was made of the chest X-ray features of 120 patients who underwent surgical treatment for mediastinal non-vascular pathologies over the past 12 years in the Mestre Hospital. A method of analysis is proposed which takes into account not only the differences between the immediate post-operative period and the follow-up, but also the anatomotopographic partition and the surgical practice. Normal and pathological patterns for both of the above periods are described. The ''dimness'' of the arial tracheogram is emphasized as a usefull and early sign of mediastinal recurrence

  2. Vascular comorbidities in multiple sclerosis

    DEFF Research Database (Denmark)

    Thormann, Anja; Magyari, Melinda; Koch-Henriksen, Nils

    2016-01-01

    To investigate the occurrence of vascular comorbidities before and after the clinical onset of multiple sclerosis. In this combined case-control and cohort study, all Danish born citizens with onset of multiple sclerosis 1980-2005 were identified from the Danish Multiple Sclerosis Registry...... and randomly matched with controls regarding year of birth, gender, and municipality on January 1st in the year of multiple sclerosis (MS) onset (index date). Individual-level information on comorbidities was obtained from several independent nationwide registries and linked to the study population by unique...

  3. Heritability of Retinal Vascular Fractals

    DEFF Research Database (Denmark)

    Vergmann, Anna Stage; Broe, Rebecca; Kessel, Line

    2017-01-01

    , the retinal vascular fractal dimension was measured using the box-counting method and compared within monozygotic and dizygotic twin pairs using Pearson correlation coefficients. Falconer's formula and quantitative genetic models were used to determine the genetic component of variation. Results: The mean...... fractal dimension did not differ statistically significantly between monozygotic and dizygotic twin pairs (1.505 vs. 1.495, P = 0.06), supporting that the study population was suitable for quantitative analysis of heritability. The intrapair correlation was markedly higher (0.505, P = 0...

  4. Error-correction coding

    Science.gov (United States)

    Hinds, Erold W. (Principal Investigator)

    1996-01-01

    This report describes the progress made towards the completion of a specific task on error-correcting coding. The proposed research consisted of investigating the use of modulation block codes as the inner code of a concatenated coding system in order to improve the overall space link communications performance. The study proposed to identify and analyze candidate codes that will complement the performance of the overall coding system which uses the interleaved RS (255,223) code as the outer code.

  5. Vascular cognitive impairments in chronic kidney disease

    Directory of Open Access Journals (Sweden)

    I. V. Rogova

    2015-01-01

    Full Text Available Objective: to study the specific features of development of cognitive impairments (CIs, the role of traditional cardiovascular risk factors and renal failure-induced factors in patients with Stages I–IV chronic kidney disease (CKD and to assess an association of CIs with the signs of vascular wall remodeling in them. Patients and methods. Fifty-one patients aged 53±10 years with CKD were examined. Among them, there were 20 patients with Stages I–II CKD: a glomerular filtration rate (GFR of і60 ml/min/1.73 m2, signs of renal lesion; 20 with Stages III CKD: a GFR of <60–30 ml/min/1.73 m2, and 11 with Stages VI CKD: a GFR of <30–15 ml/min/1.73 m2. Results and discussion. CIs were more common in the patients with Stages III–IV than in those with Stages I–II, as shown by the scores of the mini-mental state examination (p<0.001, the frontal assessment battery (p=0.001, and the regulatory function test (p<0.001. These tests showed that the magnitude of CIs increased with the higher stage of CKD. Stages III–IV CKD is an independent predictor of CIs in persons with predialysis-stage kidney lesion. CIs were found to be related to hyperhomocysteinemia, anemia, abdominal obesity, left ventricular hypertrophy, and patient age. The signs of atherosclerotic lesion of the common carotid arteries and the indicators of arterial stiffness were also associated with the incidence and magnitude of CIs in CKD. The detection of CIs in patients with early CKD allows one to timely initiate adequate therapy aimed particularly at improving cerebral circulation, eliminating the impact of risk factors, and slowing down the vascular remodeling. The management tactics for patients with CKD must involve the identification and correction of cardiovascular risk factors, and duplex scanning of the wall of the common carotid arteries may be used as a noninvasive method to assess the risk of the development and progression of CIs in predialysis CKD. 

  6. Molecular mechanism of Na+,K+-ATPase malfunction in mutations characteristic of adrenal hypertension

    DEFF Research Database (Denmark)

    Kopec, Wojciech; Loubet, Bastien; Poulsen, Hanne

    2014-01-01

    the sodium leak measured with the mutant. The last mutant, EETA956S, opens an additional water pathway near the C-terminus, affecting the III sodium-specific binding site. The results are in excellent agreement with recent electrophysiology measurements and suggest how three mutations prevent the occlusion......), which shows inward leak currents under physiological conditions. The first three mutations affect the structural context of the key ion-binding residue Glu327 at binding site II, which leads to the loss of the ability to bind ions correctly and to occlude the pump. The mutated residue in L97R is more...... hydrated, which ultimately leads to the observed proton leak. V325G mimics the structural behavior of L97R; however, it does not promote the hydration of surrounding residues. In Del93-97, a broader opening is observed because of the rearrangement of the kinked transmembrane helix 1, M1, which may explain...

  7. CIRSE Vascular Closure Device Registry

    International Nuclear Information System (INIS)

    Reekers, Jim A.; Müller-Hülsbeck, Stefan; Libicher, Martin; Atar, Eli; Trentmann, Jens; Goffette, Pierre; Borggrefe, Jan; Zeleňák, Kamil; Hooijboer, Pieter; Belli, Anna-Maria

    2011-01-01

    Purpose: Vascular closure devices are routinely used after many vascular interventional radiology procedures. However, there have been no major multicenter studies to assess the safety and effectiveness of the routine use of closure devices in interventional radiology. Methods: The CIRSE registry of closure devices with an anchor and a plug started in January 2009 and ended in August 2009. A total of 1,107 patients were included in the registry. Results: Deployment success was 97.2%. Deployment failure specified to access type was 8.8% [95% confidence interval (95% CI) 5.0–14.5] for antegrade access and 1.8% (95% CI 1.1–2.9) for retrograde access (P = 0.001). There was no difference in deployment failure related to local PVD at the access site. Calcification was a reason for deployment failure in only 5.9 cm, and two vessel occlusions. Conclusion: The conclusion of this registry of closure devices with an anchor and a plug is that the use of this device in interventional radiology procedures is safe, with a low incidence of serious access site complications. There seems to be no difference in complications between antegrade and retrograde access and other parameters.

  8. Neuroradiological findings in vascular dementia

    Energy Technology Data Exchange (ETDEWEB)

    Guermazi, Ali; Miaux, Yves; Suhy, Joyce; Pauls, Jon; Lopez, Ria [Synarc, Inc., Department of Radiology Services, San Francisco, CA (United States); Rovira-Canellas, Alex [Hospital General Universitari Vall d' Hebron, Unita de Resonancia Magnetica, Barcelona (Spain); Posner, Holly [Eisai, Inc., Teaneck, NJ (United States)

    2007-01-15

    There are multiple diagnostic criteria for vascular dementia (VaD) that may define different populations. Utilizing the criteria of the National Institute of Neurological Disorders and Stroke and Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS-AIREN) has provided improved consistency in the diagnosis of VaD. The criteria include a table listing brain imaging lesions associated with VaD. The different neuroradiological aspects of the criteria are reviewed based on the imaging data from an ongoing large-scale clinical trial testing a new treatment for VaD. The NINDS-AIREN criteria were applied by a centralized imaging rater to determine eligibility for enrollment in 1,202 patients using brain CT or MRI. Based on the above data set, the neuroradiological features that are associated with VaD and that can result from cerebral small-vessel disease with extensive leukoencephalopathy or lacunae (basal ganglia or frontal white matter), or may be the consequence of single strategically located infarcts or multiple infarcts in large-vessel territories, are illustrated. These features may also be the consequence of global cerebral hypoperfusion, intracerebral hemorrhage, or other mechanisms such as genetically determined arteriopathies. Neuroimaging confirmation of cerebrovascular disease in VaD provides information about the topography and severity of vascular lesions. Neuroimaging may also assist with the differential diagnosis of dementia associated with normal pressure hydrocephalus, chronic subdural hematoma, arteriovenous malformation or tumoral diseases. (orig.)

  9. Diffuse and vascular hepatic diseases

    International Nuclear Information System (INIS)

    Kreimeyer, S.; Grenacher, L.

    2011-01-01

    In addition to focal liver lesions, diffuse and vascular disorders of the liver represent a wide spectrum of liver diseases which are from the radiological point of view often difficult or nearly impossible to diagnose. Classical diagnostic methods are computed tomography and magnetic resonance imaging in addition to ultrasound. Diffuse parenchymal damage caused by diseases of various etiologies is therefore difficult to evaluate because it often lacks characteristic morphological features. For hepatic steatosis, hemochromatosis/siderosis as an example of a diffuse storage disease and sarcoidosis and candidiasis as infectious/inflammatory diseases, an image-based diagnosis is appropriate in some cases. For most diffuse liver diseases, however only nonspecific changes are visualized. Vascular pathologies of the liver, such as the Budd-Chiari syndrome and portal vein thrombosis, however, can usually be diagnosed very clearly using radiology and there is also a very effective interventional radiological treatment. Chronic diseases very often culminate in liver cirrhosis which is highly associated with an increased risk of liver cancer. (orig.) [de

  10. CIRSE Vascular Closure Device Registry

    Science.gov (United States)

    Müller-Hülsbeck, Stefan; Libicher, Martin; Atar, Eli; Trentmann, Jens; Goffette, Pierre; Borggrefe, Jan; Zeleňák, Kamil; Hooijboer, Pieter; Belli, Anna-Maria

    2010-01-01

    Purpose Vascular closure devices are routinely used after many vascular interventional radiology procedures. However, there have been no major multicenter studies to assess the safety and effectiveness of the routine use of closure devices in interventional radiology. Methods The CIRSE registry of closure devices with an anchor and a plug started in January 2009 and ended in August 2009. A total of 1,107 patients were included in the registry. Results Deployment success was 97.2%. Deployment failure specified to access type was 8.8% [95% confidence interval (95% CI) 5.0–14.5] for antegrade access and 1.8% (95% CI 1.1–2.9) for retrograde access (P = 0.001). There was no difference in deployment failure related to local PVD at the access site. Calcification was a reason for deployment failure in only 5.9 cm, and two vessel occlusions. Conclusion The conclusion of this registry of closure devices with an anchor and a plug is that the use of this device in interventional radiology procedures is safe, with a low incidence of serious access site complications. There seems to be no difference in complications between antegrade and retrograde access and other parameters. PMID:20981425

  11. Enhanced Recovery after Vascular Surgery

    Directory of Open Access Journals (Sweden)

    Milena D. Stojanovic

    2018-01-01

    Full Text Available The beginnings of the enhanced recovery after surgery (ERAS program were first developed for patients in colorectal surgery, and after it was established as the standard of care in this surgical field, it began to be applied in many others surgical areas. This is multimodal, evidence-based approach program and includes simultaneous optimization of preoperative status of patients, adequate selection of surgical procedure and postoperative management. The aim of this program is to reduce complications, the length of hospital stay and to improve the patients outcome. Over the past decades, special attention was directed to the postoperative management in vascular surgery, especially after major vascular surgery because of the great risk of multiorgan failure, such as: respiratory failure, myocardial infarction, hemodynamic instability, coagulopathy, renal failure, neurological disorders, and intra-abdominal complications. Although a lot of effort was put into it, there is no unique acceptable program for ERAS in this surgical field, and there is still a need to point out the factors responsible for postoperative outcomes of these patients. So far, it is known that special attention should be paid to already existing diseases, type and the duration of the surgical intervention, hemodynamic and fluid management, nutrition, pain management, and early mobilization of patients.

  12. Vascular access for home haemodialysis.

    Science.gov (United States)

    Al Shakarchi, Julien; Day, C; Inston, N

    2018-03-01

    Home haemodialysis has been advocated due to improved quality of life. However, there are very little data on the optimum vascular access for it. A retrospective cohort study was carried on all patients who initiated home haemodialysis between 2011 and 2016 at a large university hospital. Access-related hospital admissions and interventions were used as primary outcome measures. Our cohort consisted of 74 patients. On initiation of home haemodialysis, 62 individuals were using an arteriovenous fistula as vascular access, while the remaining were on a tunnelled dialysis catheter. Of the 12 patients who started on a tunnelled dialysis catheter, 5 were subsequently converted to either an arteriovenous fistula ( n = 4) or an arteriovenous graft ( n = 1). During the period of home haemodialysis use, four arteriovenous fistula failed or thrombosed with patients continuing on home haemodialysis using an arteriovenous graft ( n = 3) or a tunnelled dialysis catheter ( n = 1). To maintain uninterrupted home haemodialysis, interventional rates were 0.32 per arteriovenous fistula/arteriovenous graft access-year and 0.4 per tunnelled dialysis catheter access-year. Hospital admission rates for patients on home haemodialysis were 0.33 per patient-year. Our study has shown that home haemodialysis can be safely and independently performed at home within a closely managed home haemodialysis programme. The authors also advocate the use of arteriovenous fistulas for this cohort of patients due to both low complication and intervention rates.

  13. Vascular emergencies in liver trauma

    Energy Technology Data Exchange (ETDEWEB)

    Taourel, P. [Centre Hospitalier Universitaire Lapeyronie, Montpellier (France)], E-mail: p-taourel@chu-montpellier.fr; Vernhet, H. [Centre Hospitalier Universitaire Arnaud de Villeneuve, Montpellier (France); Suau, A.; Granier, C. [Centre Hospitalier Universitaire Lapeyronie, Montpellier (France); Lopez, F.M. [Centre Hospitalier Universitaire, Nimes (France); Aufort, S. [Centre Hospitalier Universitaire Lapeyronie, Montpellier (France)

    2007-10-15

    The use of CT in the diagnosis and management of liver trauma is responsible for the shift from routine surgical versus non-surgical treatment in the management of traumatic liver injuries, even when they are of high grade. The main cause of compli cation and of death in liver trauma is related to vascular injury. The goal of this review focussed on the vascular complications of liver trauma is to describe the elementary lesions shown by CT in liver trauma including laceration, parenchymal hematoma and contusions, partial devascularisation, subcapsular hematomas, hemoperitoneum, active bleeding, pseudoaneurysm of the hepatic artery, bile leak, and periportal oedema, to illustrate the possible pitfalls in CT diagnosis of liver trauma and to underline the key-points which may absolutely be present in a CT report of liver trauma. Then we will remind the grading system based on the CT features and we will analyze the interest and limitations of such grading systems. Last we will discuss the diagnostic strategy at the early phase in patients with suspected liver trauma according to their clinical conditions and underline the conditions of arterial embolization, and then we will discuss the diagnosis strategy at the delayed phase according to the suspected complications.

  14. Vascular emergencies in liver trauma

    International Nuclear Information System (INIS)

    Taourel, P.; Vernhet, H.; Suau, A.; Granier, C.; Lopez, F.M.; Aufort, S.

    2007-01-01

    The use of CT in the diagnosis and management of liver trauma is responsible for the shift from routine surgical versus non-surgical treatment in the management of traumatic liver injuries, even when they are of high grade. The main cause of compli cation and of death in liver trauma is related to vascular injury. The goal of this review focussed on the vascular complications of liver trauma is to describe the elementary lesions shown by CT in liver trauma including laceration, parenchymal hematoma and contusions, partial devascularisation, subcapsular hematomas, hemoperitoneum, active bleeding, pseudoaneurysm of the hepatic artery, bile leak, and periportal oedema, to illustrate the possible pitfalls in CT diagnosis of liver trauma and to underline the key-points which may absolutely be present in a CT report of liver trauma. Then we will remind the grading system based on the CT features and we will analyze the interest and limitations of such grading systems. Last we will discuss the diagnostic strategy at the early phase in patients with suspected liver trauma according to their clinical conditions and underline the conditions of arterial embolization, and then we will discuss the diagnosis strategy at the delayed phase according to the suspected complications

  15. Vascularized bone transplant chimerism mediated by vascular endothelial growth factor.

    Science.gov (United States)

    Willems, Wouter F; Larsen, Mikko; Friedrich, Patricia F; Bishop, Allen T

    2015-01-01

    Vascular endothelial growth factor (VEGF) induces angiogenesis and osteogenesis in bone allotransplants. We aim to determine whether bone remodeling in VEGF-treated bone allotransplants results from repopulation with circulation-derived autogenous cells or survival of allogenic transplant-derived cells. Vascularized femoral bone transplants were transplanted from female Dark Agouti rats (DA;RT1(a) ) to male Piebald Viral Glaxo (PVG;RT1(c) ). Arteriovenous bundle implantation and short-term immunosuppression were used to maintain cellular viability. VEGF was encapsulated in biodegradable microspheres and delivered intramedullary in the experimental group (n = 22). In the control group (n = 22), no VEGF was delivered. Rats were sacrificed at 4 or 18 weeks. Laser capture microdissection of bone remodeling areas was performed at the inner and outer cortex. Sex-mismatched genes were quantified with reverse transcription-polymerase chain reaction to determine the amount of male cells to total cells, defined as the relative expression ratio (rER). At 4 weeks, rER was significantly higher at the inner cortex in VEGF-treated transplants as compared to untreated transplants (0.622 ± 0.225 vs. 0.362 ± 0.081, P = 0.043). At 4 weeks, the outer cortex in the control group had a significantly higher rER (P = 0.038), whereas in the VEGF group, the inner cortex had a higher rER (P = 0.015). Over time, in the outer cortex the rER significantly increased to 0.634 ± 0.106 at 18 weeks in VEGF-treated rats (P = 0.049). At 18 weeks, the rER was >0.5 at all cortical areas in both groups. These in vivo findings suggest a chemotactic effect of intramedullary applied VEGF on recipient-derived bone and could imply that more rapid angiogenesis of vascularized allotransplants can be established with microencapsulated VEGF. © 2014 Wiley Periodicals, Inc.

  16. CORRECTED MARCH EDITON 2009 F...

    African Journals Online (AJOL)

    User

    motor, autonomic) and peripheral vascular disease. (macro and ... Several risk factors predispose the diabetic patient to foot ulceration, including. “inadequate care of the .... which score 1 point. The impact of site of discomfort, time of worst.

  17. Proatherogenic pathways leading to vascular calcification

    International Nuclear Information System (INIS)

    Mazzini, Michael J.; Schulze, P. Christian

    2006-01-01

    Cardiovascular disease is the leading cause of morbidity and mortality in the western world and atherosclerosis is the major common underlying disease. The pathogenesis of atherosclerosis involves local vascular injury, inflammation and oxidative stress as well as vascular calcification. Vascular calcification has long been regarded as a degenerative process leading to mineral deposition in the vascular wall characteristic for late stages of atherosclerosis. However, recent studies identified vascular calcification in early stages of atherosclerosis and its occurrence has been linked to clinical events in patients with cardiovascular disease. Its degree correlates with local vascular inflammation and with the overall impact and the progression of atherosclerosis. Over the last decade, diverse and highly regulated molecular signaling cascades controlling vascular calcification have been described. Local and circulating molecules such as osteopontin, osteoprogerin, leptin and matrix Gla protein were identified as critical regulators of vascular calcification. We here review the current knowledge on molecular pathways of vascular calcification and their relevance for the progression of cardiovascular disease

  18. World Federation of Vascular Societies: presidential address

    DEFF Research Database (Denmark)

    Sillesen, Henrik Hegaard

    2010-01-01

    The presidential address describes briefly the history of the World Federation for Vascular Societies (WFVS) and its objectives. Vascular Surgery today includes interventional procedures (open surgical and endovascular) in addition to risk factor reduction and medical treatment. It is equally imp...... throughout the world. In addition, for introduction of new treatments, training issues and dissemination of science a global organisation like the WFVS is needed.......The presidential address describes briefly the history of the World Federation for Vascular Societies (WFVS) and its objectives. Vascular Surgery today includes interventional procedures (open surgical and endovascular) in addition to risk factor reduction and medical treatment. It is equally...

  19. Association between homocyst(e)ine levels and risk of vascular events.

    Science.gov (United States)

    Kaplan, Eugene D

    2003-03-01

    Homocyst(e)ine is a novel risk factor in vascular disease. First observations of vascular lesions in children with high blood homocyst(e)ine levels due to severe inborn enzyme deficiencies led to the hypothesis that elevated blood homocyst(e)ine levels might be a risk factor for vascular disease. A substantial body of evidence on the role of the homocyst(e)ine in the development of coronary and carotid artery disease, myocardial infarction, stroke, deep vein thrombosis and other disorders has been accumulated over the last 30 years. Cross-sectional and case-control studies provide initial and the strongest support for the hypothesis, followed by results from the prospective cohorts. Infrequent cases of homozygous mutations of the key enzymes in the homocyst(e)ine metabolism chain are able to produce extreme homocyst(e)inemia and early vascular lesions. More frequently, heterozygous enzyme mutations and deficiencies of folate and vitamins B6 and B12 cause mild to moderate homocyst(e)inemia, which is still strongly associated with the increased risk of vascular events. Elevated homocyst(e)ine levels may be effectively managed with adequate folate, B12 and B6 intake in doses comparable to or above FDA recommendations. Whether correction of elevated homocyst(e)ine levels with vitamins is helpful in prevention and treatment of vascular events remains unknown and is under investigation in ongoing clinical trials (VISP, VITATOPS). No consensus on homocyst(e)ine management is available at the present time.

  20. Brain Image Motion Correction

    DEFF Research Database (Denmark)

    Jensen, Rasmus Ramsbøl; Benjaminsen, Claus; Larsen, Rasmus

    2015-01-01

    The application of motion tracking is wide, including: industrial production lines, motion interaction in gaming, computer-aided surgery and motion correction in medical brain imaging. Several devices for motion tracking exist using a variety of different methodologies. In order to use such devices...... offset and tracking noise in medical brain imaging. The data are generated from a phantom mounted on a rotary stage and have been collected using a Siemens High Resolution Research Tomograph for positron emission tomography. During acquisition the phantom was tracked with our latest tracking prototype...

  1. Is attenuation correction of myocardial SPECT scans worth the effort?

    International Nuclear Information System (INIS)

    Bui, C.; Nguyen, D.; Dixson, H.; Saunders, C.; Cook, P.; Burnett, P.; Croll, F.; Dunn, R.; Hasche, E.; Kelleher, P.; Nasser, F.; Wilson, D.; Lee, K.

    2000-01-01

    Full text: Gated (GS), attenuation-corrected (AC) and non-attenuation-corrected (NAC) myocardial SPECT scans were performed after injection of 99 Tc m -Sestamibi (MIBI) at peak stress in 253 patients between September 1998 and March 1999. 60 patients have undergone cardiac catheterisation (37 males, 23 females, age range 34-80). For whole heart analysis, significant coronary disease was defined as 50% or greater diameter narrowing in any of the coronary arteries and/or documented myocardial infarction. For vascular territory analysis, significant coronary disease was defined as 50% or greater diameter narrowing of any artery in that territory. The three coronary artery territories were assigned as: left anterior descending (LAD), left circumflex (LCA) and right coronary (RCA). The septum, apex and anterior wall; the lateral wall; and the inferior wall were assigned to the LAD; LCA; and RCA territories respectively. In conclusion for this selected subgroup of patients with angiographic follow-up, NAC, AC and GS were of similar accuracy in the detection of significant CAD in both whole heart analysis and individual vascular territory analysis. AC and GS were of superior specificity when compared with NAC in both whole heart analysis and individual vascular territory analysis. AC and GS may be of additional diagnostic value in improving the specificity of NAC. Further outcome data will be presented. Copyright (2000) The Australian and New Zealand Society of Nuclear Medicine Inc

  2. [Immunologic problems in vascular homografts].

    Science.gov (United States)

    D'Addato, M; Mirelli, M

    2001-01-01

    Fresh arterial homografts are immunogenic, inducing in recipient a strong immune response specifically directed against the antigens of the donor graft. The initial immune response seems to be cellular (lymphocytotoxic) and the late reaction humoral (antibody), even if they are strictly correlated. Immunosuppressive therapy reduce the immune reaction, but this response is dose-related. Implanted arterial homografts induce a donor-specific response similar to chronic reaction, which occurs in the recipients of vascularized solid-organ allografts. Therefore, in arterial transplantation, ABO compatibility and negative crossmatch should be respected. Effort should be made to curb the immune response by prospective cross-matching, immunosuppressive therapy and preoperative manipulation of homografts to reduce their antigenicity.

  3. Heritability of Retinal Vascular Fractals

    DEFF Research Database (Denmark)

    Vergmann, Anna Stage; Broe, Rebecca; Kessel, Line

    2017-01-01

    Purpose: To determine the genetic contribution to the pattern of retinal vascular branching expressed by its fractal dimension. Methods: This was a cross-sectional study of 50 monozygotic and 49 dizygotic, same-sex twin pairs aged 20 to 46 years. In 50°, disc-centered fundus photographs, the reti...... fractal dimension did not differ statistically significantly between monozygotic and dizygotic twin pairs (1.505 vs. 1.495, P = 0.06), supporting that the study population was suitable for quantitative analysis of heritability. The intrapair correlation was markedly higher (0.505, P = 0.......0002) in monozygotic twins than in dizygotic twins (0.108, P = 0.46), corresponding to a heritability h2 for the fractal dimension of 0.79. In quantitative genetic models, dominant genetic effects explained 54% of the variation and 46% was individually environmentally determined. Conclusions: In young adult twins...

  4. Vascular anastomosis by Argon Laser

    International Nuclear Information System (INIS)

    Gomes, O.M.; Macruz, R.; Armelin, E.; Brum, J.M.G.; Ribeiro, M.P.; Mnitentog, J.; Verginelli, G.; Pileggi, F.; Zerbini, E.J.

    1982-01-01

    Twenty four mongrel dogs, wheighing 13 to 24 kilograms were studied. After anesthesia, intubation and controlled ventilation, they were submitted to three types of vascular anastomosis: Group I - eight dogs with saphenous vein inter-carotid arteries by-pass: Group II - eight dogs with left mammary artery - left anterior descending coronary artery by-pass; Group III - eight dogs with venovenous anastomosis. In all groups 0.8 to 15 watts of Argon Laser power was applied to a total time of 90 to 300 seconds. The lower power for venovenous anastomosis and the greater for the arterial ones. The mean valves of resistence of the Laser anastomosis to pressure induced rupture was 730 mmHg in the immediate post operative study, and superior to 2.500 mmHg 30 days after. No signs of occlusion was demonstrated at the anastomosis sites by the angiographic and anathomo-patological study performed. (Author) [pt

  5. Vascular targeting with peptide libraries

    Energy Technology Data Exchange (ETDEWEB)

    Pasqualini, R. [La Jolla Cancer Research Center The Burnham Inst., La Jolla CA (United States)

    1999-06-01

    The authors have developed an 'in vivo' selection system in which phage capable of selective homing to different tissues are recovered from a phage display peptide library following intravenous administration. Using this strategy, they have isolate several organ and tumor-homing peptides. They have shown that each of those peptides binds of different receptors that are selectively expressed on the vasculature of the target tissue. The tumor-homing peptides bind to receptors that are up regulated in tumor angiogenic vasculature. Targeted delivery of doxorubicin to angiogenic vasculature using these peptides in animals models decrease toxicity and increased the therapeutic efficacy of the drug. Vascular targeting may facilitate the development of other treatment strategies that rely on inhibition of angio genesis and lead to advances to extend the potential for targeting of drugs, genes and radionuclides in the context of many diseases.

  6. Vascular Morphodynamics During Secondary Growth.

    Science.gov (United States)

    de Reuille, Pierre Barbier; Ragni, Laura

    2017-01-01

    Quantification of vascular morphodynamics during secondary growth has been hampered by the scale of the process. Even in the tiny model plant Arabidopsis thaliana, the xylem can include more than 2000 cells in a single cross section, rendering manual counting impractical. Moreover, due to its deep location, xylem is an inaccessible tissue, limiting live imaging. A novel method to visualize and measure secondary growth progression has been proposed: "the Quantitative Histology" approach. This method is based on a detailed anatomical atlas, and image segmentation coupled with machine learning to automatically extract cell shapes and identify cell type. Here we present a new version of this approach, with a user-friendly interface implemented in the open source software LithoGraphX.

  7. Adiposity, adipocytokines & microvesicles in the etiology of vascular disease

    NARCIS (Netherlands)

    Kanhai, D.A.N.I.S.

    2013-01-01

    Vascular disease, in this thesis the terms vascular and cardiovascular are used interchangeably, is the number 1 cause of death worldwide. In 2008, 30% of all mortality had a vascular origin. Vascular mortality rates after a first manifestation of vascular disease are decreasing in Western society,

  8. FPGA controlled artificial vascular system

    Directory of Open Access Journals (Sweden)

    Laqua D.

    2015-09-01

    Full Text Available Monitoring the oxygen saturation of an unborn child is an invasive procedure, so far. Transabdominal fetal pulse oximetry is a promising method under research, used to estimate the oxygen saturation of a fetus noninvasively. Due to the nature of the method, the fetal information needs to be extracted from a mixed signal. To properly evaluate signal processing algorithms, a phantom modeling fetal and maternal blood circuits and tissue layers is necessary. This paper presents an improved hardware concept for an artificial vascular system, utilizing an FPGA based CompactRIO System from National Instruments. The experimental model to simulate the maternal and fetal blood pressure curve consists of two identical hydraulic circuits. Each of these circuits consists of a pre-pressure system and an artificial vascular system. Pulse curves are generated by proportional valves, separating these two systems. The dilation of the fetal and maternal artificial vessels in tissue substitutes is measured by transmissive and reflective photoplethysmography. The measurement results from the pressure sensors and the transmissive optical sensors are visualized to show the functionality of the pulse generating systems. The trigger frequency for the maternal valve was set to 1 per second, the fetal valve was actuated at 0.7 per second for validation. The reflective curve, capturing pulsations of the fetal and maternal circuit, was obtained with a high power LED (905 nm as light source. The results show that the system generates pulse curves, similar to its physiological equivalent. Further, the acquired reflective optical signal is modulated by the alternating diameter of the tubes of both circuits, allowing for tests of signal processing algorithms.

  9. Store-Carry and Forward-Type M2M Communication Protocol Enabling Guide Robots to Work together and the Method of Identifying Malfunctioning Robots Using the Byzantine Algorithm

    Directory of Open Access Journals (Sweden)

    Yoshio Suga

    2016-11-01

    Full Text Available This paper concerns a service in which multiple guide robots in an area display arrows to guide individual users to their destinations. It proposes a method of identifying malfunctioning robots and robots that give wrong directions to users. In this method, users’ mobile terminals and robots form a store-carry and forward-type M2M communication network, and a distributed cooperative protocol is used to enable robots to share information and identify malfunctioning robots using the Byzantine algorithm. The robots do not directly communicate with each other, but through users’ mobile terminals. We have introduced the concept of the quasi-synchronous number, so whether a certain robot is malfunctioning can be determined even when items of information held by all of the robots are not synchronized. Using simulation, we have evaluated the proposed method in terms of the rate of identifying malfunctioning robots, the rate of reaching the destination and the average length of time to reach the destination.

  10. Dynamics of nephron-vascular network

    DEFF Research Database (Denmark)

    Postnov, Dmitry; Postnov, D E; Marsh, D J

    2012-01-01

    The paper presents a modeling study of the spatial dynamics of a nephro-vascular network consisting of individual nephrons connected via a tree-like vascular branching structure. We focus on the effects of nonlinear mechanisms that are responsible for the formation of synchronous patterns in order...

  11. Imaging of the peripheral vascular system

    International Nuclear Information System (INIS)

    Gould, S.A.; Pond, G.D.; Pinsky, S.; Moss, G.S.; Srikantaswamy, S.; Ryo, U.Y.

    1984-01-01

    This book is limited neither to the peripheral vascular system nor to diagnostic imaging techniques. Its 18 chapters cover nonimaging blood-flow techniques (Doppler ultrasound, plethysmography) as well as noninvasive and invasive imaging techniques (ultrasound, computed tomography, radionuclide digital-subtraction angiography, and contrast angiography). These are applied not only to the peripheral vascular system but also to the aorta and vena cava

  12. Biomarkers of drug-induced vascular injury

    International Nuclear Information System (INIS)

    Brott, D.; Gould, S.; Jones, H.; Schofield, J.; Prior, H.; Valentin, J.P; Bjurstrom, S.; Kenne, K.; Schuppe-Koistinen, I.; Katein, A.; Foster-Brown, L.; Betton, G.; Richardson, R.; Evans, G.; Louden, C.

    2005-01-01

    In pre-clinical safety studies, drug-induced vascular injury is an issue of concern because there are no obvious diagnostic markers for pre-clinical or clinical monitoring and there is an intellectual gap in our understanding of the pathogenesis of this lesion. While vasodilatation and increased shear stress appear to play a role, the exact mechanism(s) of injury to the primary targets, smooth muscle and endothelial cells are unknown. However, evaluation of novel markers for potential clinical monitoring with a mechanistic underpinning would add value in risk assessment and management. This mini review focuses on the progress to identify diagnostic markers of drug-induced vascular injury. Von Willebrand factor (vWF), released upon perturbation of endothelial cells, is transiently increased in plasma prior to morphological evidence of damage in dogs or rats treated with vascular toxicants. Therefore, vWF might be a predictive biomarker of vascular injury. However, vWF is not an appropriate biomarker of lesion progression or severity since levels return to baseline values when there is morphological evidence of injury. A potential mechanistically linked biomarker of vascular injury is caveolin-1. Expression of this protein, localized primarily to smooth muscle and endothelial cells, decreases with the onset of vascular damage. Since vascular injury involves multiple mediators and cell types, evaluation of a panel rather than a single biomarker may be more useful in monitoring early and severe progressive vascular injury

  13. Reconstructive vascular surgery below the knee

    DEFF Research Database (Denmark)

    Rasmussen, L B; Jelnes, R; Sager, P

    1986-01-01

    In a series of 38 consecutive patients with advanced peripheral vascular disease (i.e. rest pain) reconstructive vascular surgery was performed with the distal anastomosis below the knee. Ankle/arm pressure index (AAI) was 0.28 (0.11-0.47) preoperatively; accumulated graft patency rate was 0.47 (SD...

  14. Vascular dementia | Connor | African Journal of Psychiatry

    African Journals Online (AJOL)

    Vascular dementia (VaD) is a common but heterogeneous condition in which there is a clear temporal relationship between the dementia and vascular disease. It may result from multiple large or small vessel strokes or a single strategic stroke. Subcortical ischaemic VaD includes multiple lacunes and subcortical ...

  15. THE FLATULENCE SYMPTOM IN SMALL CHILDREN: CAUSES AND WAYS OF CORRECTION

    Directory of Open Access Journals (Sweden)

    A. N. Surkov

    2013-01-01

    Full Text Available Gastrointestinal tract malfunctions, food allergy, intestinal microbiocenosis disorder, disaccharide insufficiency, celiac disease and several other causes lead to an increased gas-formation, overdistension of intestinal loops and abdominal pains in 0-1-year-old children. The crucial task of flatulence elimination is the correction of causes of its occurrence. Frequent intestinal spasm episodes in infants reduce the quality of life of them and their families in general and are also associated with the subsequent child’s physical and mental maldevelopments. Simethicone-based suspension (in the form of antifoaming agent helps to cope with the issue; it has carminative properties; this allows to reduce the amount of gases in the intestinal lumen, thus terminating pain symptoms.

  16. PanVascular medicine. 2. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Lanzer, Peter (ed.) [Health Care Center Bitterfeld (Germany). Division of Cardiovascular Disease

    2015-06-01

    Vascular management and care has become a truly multidisciplinary enterprise as the number of specialists involved in the treatment of patients with vascular diseases has steadily increased. While in the past, treatments were delivered by individual specialists, in the twenty-first century a team approach is without doubt the most effective strategy. In order to promote professional excellence in this dynamic and rapidly evolving field, a shared knowledge base and interdisciplinary standards need to be established. Pan Vascular Medicine, 2nd edition has been designed to offer such an interdisciplinary platform, providing vascular specialists with state-of-the art descriptive and procedural knowledge. Basic science, diagnostics, and therapy are all comprehensively covered. In a series of succinct, clearly written chapters, renowned specialists introduce and comment on the current international guidelines and present up-to-date reviews of all aspects of vascular care.

  17. Using Polymeric Scaffolds for Vascular Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Alida Abruzzo

    2014-01-01

    Full Text Available With the high occurrence of cardiovascular disease and increasing numbers of patients requiring vascular access, there is a significant need for small-diameter (<6 mm inner diameter vascular graft that can provide long-term patency. Despite the technological improvements, restenosis and graft thrombosis continue to hamper the success of the implants. Vascular tissue engineering is a new field that has undergone enormous growth over the last decade and has proposed valid solutions for blood vessels repair. The goal of vascular tissue engineering is to produce neovessels and neoorgan tissue from autologous cells using a biodegradable polymer as a scaffold. The most important advantage of tissue-engineered implants is that these tissues can grow, remodel, rebuild, and respond to injury. This review describes the development of polymeric materials over the years and current tissue engineering strategies for the improvement of vascular conduits.

  18. Postoperative radiographic evaluation of vascularized fibular grafts

    International Nuclear Information System (INIS)

    Manaster, B.J.; Coleman, D.A.; Bell, D.A.

    1989-01-01

    This paper reports on thirty-five patients with free vascularized fibular grafts examined postoperatively with plain radiography. Early graft incorporation is seen as a fuzziness of the cortex at the site of its insertion into the host bone. Causes of failure in grafting for bone defects include graft fracture, hardware failure, and infection. A high percentage of complications or at least delayed unions occurred when vascularized fibular grafts were used to fill defects in the lower extremity. Conversely, upper extremity defects bridged by vascularized grafts heal quickly and hypertrophy. Vascularized grafts placed in the femoral head and neck for a vascular necrosis incorporate early on their superior aspect. The osseous tunnel in which they are placed is normally wider than the graft and often becomes sclerotic; this appearance does not represent nonunion

  19. PanVascular medicine. 2. ed.

    International Nuclear Information System (INIS)

    Lanzer, Peter

    2015-01-01

    Vascular management and care has become a truly multidisciplinary enterprise as the number of specialists involved in the treatment of patients with vascular diseases has steadily increased. While in the past, treatments were delivered by individual specialists, in the twenty-first century a team approach is without doubt the most effective strategy. In order to promote professional excellence in this dynamic and rapidly evolving field, a shared knowledge base and interdisciplinary standards need to be established. Pan Vascular Medicine, 2nd edition has been designed to offer such an interdisciplinary platform, providing vascular specialists with state-of-the art descriptive and procedural knowledge. Basic science, diagnostics, and therapy are all comprehensively covered. In a series of succinct, clearly written chapters, renowned specialists introduce and comment on the current international guidelines and present up-to-date reviews of all aspects of vascular care.

  20. RCRA corrective action and closure

    International Nuclear Information System (INIS)

    1995-02-01

    This information brief explains how RCRA corrective action and closure processes affect one another. It examines the similarities and differences between corrective action and closure, regulators' interests in RCRA facilities undergoing closure, and how the need to perform corrective action affects the closure of DOE's permitted facilities and interim status facilities

  1. Rethinking political correctness.

    Science.gov (United States)

    Ely, Robin J; Meyerson, Debra E; Davidson, Martin N

    2006-09-01

    Legal and cultural changes over the past 40 years ushered unprecedented numbers of women and people of color into companies' professional ranks. Laws now protect these traditionally underrepresented groups from blatant forms of discrimination in hiring and promotion. Meanwhile, political correctness has reset the standards for civility and respect in people's day-to-day interactions. Despite this obvious progress, the authors' research has shown that political correctness is a double-edged sword. While it has helped many employees feel unlimited by their race, gender, or religion,the PC rule book can hinder people's ability to develop effective relationships across race, gender, and religious lines. Companies need to equip workers with skills--not rules--for building these relationships. The authors offer the following five principles for healthy resolution of the tensions that commonly arise over difference: Pause to short-circuit the emotion and reflect; connect with others, affirming the importance of relationships; question yourself to identify blind spots and discover what makes you defensive; get genuine support that helps you gain a broader perspective; and shift your mind-set from one that says, "You need to change," to one that asks, "What can I change?" When people treat their cultural differences--and related conflicts and tensions--as opportunities to gain a more accurate view of themselves, one another, and the situation, trust builds and relationships become stronger. Leaders should put aside the PC rule book and instead model and encourage risk taking in the service of building the organization's relational capacity. The benefits will reverberate through every dimension of the company's work.

  2. Vascular low-flow malformations in children: current concepts for classification, diagnosis and therapy

    International Nuclear Information System (INIS)

    Puig, Stefan; Casati, Bettina; Staudenherz, Anton; Paya, Kurosh

    2005-01-01

    Congenital vascular malformations (CVM) are made of dysplastic vessels with no cellular proliferation. Low- or slow-flow malformations (LFM) consist predominantly of venous and/or lymphatic vessels. Correct terminology is necessary for differentiating vascular malformations from tumours such as haemangiomas, in order to prevent ineffective or even adverse therapy. The role of the radiologist in the management of patients is two-fold: making the diagnosis with the use of ultrasound and magnetic resonance imaging, and performing sclerotherapy, which is the treatment of choice. Prior to sclerotherapy, percutaneous phlebography is necessary to visualize the dynamic situation inside the lesion and the flow into the adjacent vascular system. The double-needle technique is a useful therapy option reducing the risk of embolisation of the sclerosing agent. Large lesions might need subsequent surgical treatment. A multidisciplinary approach is substantial for optimal patient management

  3. [Gastric vascular lesions in cirrhosis: gastropathy and antral vascular ectasia].

    Science.gov (United States)

    Casas, Meritxell; Calvet, Xavier; Vergara, Mercedes; Bella, Maria Rosa; Junquera, Félix; Martinez-Bauer, Eva; Campo, Rafael

    2015-02-01

    Portal hypertensive gastropathy (GHP) is a complication of portal hypertension usually associated with liver cirrhosis. The pathogenesis is unclear but the presence of portal hypertension is an essential factor for its development. GHP may be asymptomatic or present as gastrointestinal bleeding or iron deficiency anemia. Endoscopic lesions vary from a mosaic pattern to diffuse red spots; the most common location is the fundus. Treatment is indicated when there is acute or chronic bleeding, as secondary prophylaxis. There is insufficient evidence to recommend primary prophylaxis in patients who have never bled. Drugs that decrease portal pressure, such as non-cardioselective beta-blockers, and/or endoscopic ablative treatments, such as argon-beam coagulation, may be used. The role of transarterial intrahepatic portosystemic shunt) or bypass surgery has been insufficiently analyzed. Antral vascular ectasia (EVA) is a rare entity in liver cirrhosis, whose pathophysiology is still unknown. Clinical presentation is similar to that of GHP and endoscopy usually shows red spots in the antrum. Biopsy is often required to differentiate EVA from GHP. There is no effective medical therapy, so endoscopic ablative therapy and, in severe cases, antrectomy are recommended. Copyright © 2014 Elsevier España, S.L.U. and AEEH y AEG. All rights reserved.

  4. Vascular elastic photoacoustic tomography in humans

    Science.gov (United States)

    Hai, Pengfei; Zhou, Yong; Liang, Jinyang; Li, Chiye; Wang, Lihong V.

    2016-03-01

    Quantification of vascular elasticity can help detect thrombosis and prevent life-threatening conditions such as acute myocardial infarction or stroke. Here, we propose vascular elastic photoacoustic tomography (VE-PAT) to measure vascular elasticity in humans. VE-PAT was developed by incorporating a linear-array-based photoacoustic computed tomography system with a customized compression stage. By measuring the deformation of blood vessels under uniaxial loading, VE-PAT was able to quantify the vascular compliance. We first demonstrated the feasibility of VE-PAT in blood vessel phantoms. In large vessel phantoms, VE-PAT detected a decrease in vascular compliance due to simulated thrombosis, which was validated by a standard compression test. In small blood vessel phantoms embedded 3 mm deep in gelatin, VE-PAT detected elasticity changes at depths that are difficult to image using other elasticity imaging techniques. We then applied VE-PAT to assess vascular compliance in a human subject and detected a decrease in vascular compliance when an occlusion occurred downstream from the measurement point, demonstrating the potential of VE-PAT in clinical applications such as detection of deep venous thrombosis.

  5. [A new specialty is born: Vascular medicine].

    Science.gov (United States)

    Laroche, J-P

    2016-05-01

    On the 4th of December 2015, the French authorities officially recognized the birth of a specialty in vascular medicine entitled CO-DES cardiology-vascular/vascular Medicine. France is the 7th country to obtain this specialty after Switzerland, Germany, Austria, Czech Republic, Slovakia and Slovenia, six countries in the EEC. It has taken years to achieve a long but exciting experience: we went from hopes to disappointments, sometimes with the blues, but lobbying helping… with sustained confidence. This article tells the story of 30 years of struggle to achieve this vascular medicine specialty. Gaston Bachelard wrote: "Nothing is obvious, nothing is given, all is built." For the construction of vascular medicine, we had to overcome many obstacles, nothing was given to us, everything was conquered. Beware "The specialist is one who knows more and more things about an increasingly restricted field, up to 'knowing everything about nothing"' recalled Ralph Barton Ferry, philosopher; so there is room for modesty and humility but also convictions. The physical examination will remain the basis of our exercise. But let us recall the contributions of all those vascular physicians who practiced in the past, together with those currently active, who built day after day, year after year, a vascular medicine of quality. It is because of the trust of our colleagues and our patients that we can occupy the place that is ours today. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  6. Diagnosis and management of vascular diseases

    International Nuclear Information System (INIS)

    Fan Xindong; Zheng Lianzhou

    2011-01-01

    Vascular disorders mainly include hemangiomas and vascular malformations, and constitute some of the most difficult diagnostic and therapeutic enigmas that can be encountered in the clinical practice. The clinical presentations are extremely variable and can range from an asymptomatic birthmark to life-threatening congestive heart failure. Attributing any of these extremely varied symptoms that a patients may present with to a vascular malformation may be a challenge to the most experienced clinical. This problem is compounded by the extreme rarity of these vascular lesions. If a clinician meets such a patient once every few years, it will be extremely difficult for the physicians to gain a steep learning curve. In such circumstances, it is difficult to formulate a standard of diagnosis and treatment for these vascular disorders. This paper aims to make a comprehensive and detailed description of the classification and diagnosis of the vascular disorders, the common used embolization agents, the concepts of interventional diagnosis and management and the therapies of various hemangiomas and vascular malformations. (authors)

  7. Urinary excretion of beta 2-glycoprotein-1 (apolipoprotein H) and other markers of tubular malfunction in "non-tubular" renal disease.

    Science.gov (United States)

    Flynn, F V; Lapsley, M; Sansom, P A; Cohen, S L

    1992-07-01

    To determine whether urinary beta 2-glycoprotein-1 assays can provide improved discrimination between chronic renal diseases which are primarily of tubular or glomerular origin. Urinary beta 2-glycoprotein-1, retinol-binding protein, alpha 1-microglobulin, beta 2-microglobulin, N-acetyl-beta-D-glucosa-minidase and albumin were measured in 51 patients with primary glomerular disease, 23 with obstructive nephropathy, and 15 with polycystic kidney disease, and expressed per mmol of creatinine. Plasma beta 2-glycoprotein-1 was assayed in 52 patients and plasma creatinine in all 89. The findings were compared between the diagnostic groups and with previously published data relating to primary tubular disorders. All 31 patients with plasma creatinine greater than 200 mumol/l excreted increased amounts of beta 2-glycoprotein-1, retinol-binding protein, and alpha 1-microglobulin, and 29 had increased N-acetyl-beta-D-glucosaminidase; the quantities were generally similar to those found in comparable patients with primary tubular pathology. Among 58 with plasma creatinine concentrations under 200 mumol/l, increases in beta 2-glycoprotein-1, retinol-binding protein, and alpha 1-microglobulin excretion were less common and much smaller, especially in those with obstructive nephropathy and polycystic disease. The ratios of the excretion of albumin to the other proteins provided the clearest discrimination between the patients with glomerular or tubular malfunction, but an area of overlap was present which embraced those with obstructive nephropathy and polycystic disease. Increased excretion of beta 2-glycoprotein-1 due to a raised plasma concentration or diminution of tubular reabsorption, or both, is common in all the forms of renal disease investigated, and both plasma creatinine and urinary albumin must be taken into account when interpreting results. Ratios of urinary albumin: beta 2-glycoprotein-1 greater than 1000 are highly suggestive of primary glomerular disease and

  8. Correction to toporek (2014).

    Science.gov (United States)

    2015-01-01

    Reports an error in "Pedagogy of the privileged: Review of Deconstructing Privilege: Teaching and Learning as Allies in the Classroom" by Rebecca L. Toporek (Cultural Diversity and Ethnic Minority Psychology, 2014[Oct], Vol 20[4], 621-622). This article was originally published online incorrectly as a Brief Report. The article authored by Rebecca L. Toporek has been published correctly as a Book Review in the October 2014 print publication (Vol. 20, No. 4, pp. 621-622. http://dx.doi.org/10.1037/a0036529). (The following abstract of the original article appeared in record 2014-42484-006.) Reviews the book, Deconstructing Privilege: Teaching and Learning as Allies in the Classroom edited by Kim A. Case (2013). The purpose of this book is to provide a collection of resources for those teaching about privilege directly, much of this volume may be useful for expanding the context within which educators teach all aspects of psychology. Understanding the history and systems of psychology, clinical practice, research methods, assessment, and all the core areas of psychology could be enhanced by consideration of the structural framework through which psychology has developed and is maintained. The book presents a useful guide for educators, and in particular, those who teach about systems of oppression and privilege directly. For psychologists, this guide provides scholarship and concrete strategies for facilitating students' awareness of multiple dimensions of privilege across content areas. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  9. Radiation protection: A correction

    International Nuclear Information System (INIS)

    1972-01-01

    An error in translation inadvertently distorted the sense of a paragraph in the article entitled 'Ecological Aspects of Radiation Protection', by Dr. P. Recht, which appeared in the Bulletin, Volume 14, No. 2 earlier this year. In the English text the error appears on Page 28, second paragraph, which reads, as published: 'An instance familiar to radiation protection specialists, which has since come to be regarded as a classic illustration of this approach, is the accidental release at the Windscale nuclear centre in the north of England.' In the French original of this text no reference was made, or intended, to the accidental release which took place in 1957; the reference was to the study of the critical population group exposed to routine releases from the centre, as the footnote made clear. A more correct translation of the relevant sentence reads: 'A classic example of this approach, well-known to radiation protection specialists, is that of releases from the Windscale nuclear centre, in the north of England.' A second error appeared in the footnote already referred to. In all languages, the critical population group studied in respect of the Windscale releases is named as that of Cornwall; the reference should be, of course, to that part of the population of Wales who eat laver bread. (author)

  10. Thermodynamics of Error Correction

    Directory of Open Access Journals (Sweden)

    Pablo Sartori

    2015-12-01

    Full Text Available Information processing at the molecular scale is limited by thermal fluctuations. This can cause undesired consequences in copying information since thermal noise can lead to errors that can compromise the functionality of the copy. For example, a high error rate during DNA duplication can lead to cell death. Given the importance of accurate copying at the molecular scale, it is fundamental to understand its thermodynamic features. In this paper, we derive a universal expression for the copy error as a function of entropy production and work dissipated by the system during wrong incorporations. Its derivation is based on the second law of thermodynamics; hence, its validity is independent of the details of the molecular machinery, be it any polymerase or artificial copying device. Using this expression, we find that information can be copied in three different regimes. In two of them, work is dissipated to either increase or decrease the error. In the third regime, the protocol extracts work while correcting errors, reminiscent of a Maxwell demon. As a case study, we apply our framework to study a copy protocol assisted by kinetic proofreading, and show that it can operate in any of these three regimes. We finally show that, for any effective proofreading scheme, error reduction is limited by the chemical driving of the proofreading reaction.

  11. Cross plane scattering correction

    International Nuclear Information System (INIS)

    Shao, L.; Karp, J.S.

    1990-01-01

    Most previous scattering correction techniques for PET are based on assumptions made for a single transaxial plane and are independent of axial variations. These techniques will incorrectly estimate the scattering fraction for volumetric PET imaging systems since they do not take the cross-plane scattering into account. In this paper, the authors propose a new point source scattering deconvolution method (2-D). The cross-plane scattering is incorporated into the algorithm by modeling a scattering point source function. In the model, the scattering dependence both on axial and transaxial directions is reflected in the exponential fitting parameters and these parameters are directly estimated from a limited number of measured point response functions. The authors' results comparing the standard in-plane point source deconvolution to the authors' cross-plane source deconvolution show that for a small source, the former technique overestimates the scatter fraction in the plane of the source and underestimate the scatter fraction in adjacent planes. In addition, the authors also propose a simple approximation technique for deconvolution

  12. Vascular inflammatory cells in hypertension

    Directory of Open Access Journals (Sweden)

    David G. Harrison

    2012-05-01

    Full Text Available Hypertension is a common disorder with uncertain etiology. In the last several years, it has become evident that components of both the innate and adaptive immune system play an essential role in hypertension. Macrophages and T cells accumulate in the perivascular fat, the heart and the kidney of hypertensive patients and in animals with experimental hypertension. Various immunosuppressive agents lower blood pressure and prevent end-organ damage. Mice lacking lymphocytes are protected against hypertension, and adoptive transfer of T cells, but not B cells in the animals restores their blood pressure response to stimuli such as angiotensin II or high salt. Recent studies have shown that mice lacking macrophages have blunted hypertension in response to angiotensin II and that genetic deletion of macrophages markedly reduces experimental hypertension. Dendritic cells have also been implicated in this disease. Many hypertensive stimuli have triggering effects on the central nervous system and signals arising from the circumventricular organ seem to promote inflammation. Studies have suggested that central signals activate macrophages and T cells, which home to the kidney and vasculature and release cytokines, including IL-6 and IL-17, which in turn cause renal and vascular dysfunction and lead to blood pressure elevation. These recent discoveries provide a new understanding of hypertension and provide novel therapeutic opportunities for treatment of this serious disease.

  13. Imaging evaluation of fetal vascular anomalies

    International Nuclear Information System (INIS)

    Calvo-Garcia, Maria A.; Kline-Fath, Beth M.; Koch, Bernadette L.; Laor, Tal; Adams, Denise M.; Gupta, Anita; Lim, Foong-Yen

    2015-01-01

    Vascular anomalies can be detected in utero and should be considered in the setting of solid, mixed or cystic lesions in the fetus. Evaluation of the gray-scale and color Doppler US and MRI characteristics can guide diagnosis. We present a case-based pictorial essay to illustrate the prenatal imaging characteristics in 11 pregnancies with vascular malformations (5 lymphatic malformations, 2 Klippel-Trenaunay syndrome, 1 venous-lymphatic malformation, 1 Parkes-Weber syndrome) and vascular tumors (1 congenital hemangioma, 1 kaposiform hemangioendothelioma). Concordance between prenatal and postnatal diagnoses is analyzed, with further discussion regarding potential pitfalls in identification. (orig.)

  14. Imaging evaluation of fetal vascular anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Calvo-Garcia, Maria A.; Kline-Fath, Beth M.; Koch, Bernadette L.; Laor, Tal [MLC 5031 Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Adams, Denise M. [Cincinnati Children' s Hospital Medical Center, Department of Pediatrics and Hemangioma and Vascular Malformation Center, Cincinnati, OH (United States); Gupta, Anita [Cincinnati Children' s Hospital Medical Center, Department of Pathology, Cincinnati, OH (United States); Lim, Foong-Yen [Cincinnati Children' s Hospital Medical Center, Pediatric Surgery and Fetal Center of Cincinnati, Cincinnati, OH (United States)

    2015-08-15

    Vascular anomalies can be detected in utero and should be considered in the setting of solid, mixed or cystic lesions in the fetus. Evaluation of the gray-scale and color Doppler US and MRI characteristics can guide diagnosis. We present a case-based pictorial essay to illustrate the prenatal imaging characteristics in 11 pregnancies with vascular malformations (5 lymphatic malformations, 2 Klippel-Trenaunay syndrome, 1 venous-lymphatic malformation, 1 Parkes-Weber syndrome) and vascular tumors (1 congenital hemangioma, 1 kaposiform hemangioendothelioma). Concordance between prenatal and postnatal diagnoses is analyzed, with further discussion regarding potential pitfalls in identification. (orig.)

  15. Vascular ring complicates accidental button battery ingestion.

    Science.gov (United States)

    Mercer, Ronald W; Schwartz, Matthew C; Stephany, Joshua; Donnelly, Lane F; Franciosi, James P; Epelman, Monica

    2015-01-01

    Button battery ingestion can lead to dangerous complications, including vasculoesophageal fistula formation. The presence of a vascular ring may complicate battery ingestion if the battery lodges at the level of the ring and its important vascular structures. We report a 4-year-old boy with trisomy 21 who was diagnosed with a vascular ring at the time of button battery ingestion and died 9 days after presentation due to massive upper gastrointestinal bleeding from esophageal erosion and vasculoesophageal fistula formation. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. The Megameatus, Intact Prepuce Variant of Hypospadias: Use of the Inframeatal Vascularized Flap for Surgical Correction

    OpenAIRE

    Marc Cendron

    2018-01-01

    Introduction: The megameatus intact prepuce (MIP) variant of hypospadias is a rare variant of hypospadias that is diagnosed either early at the time of circumcision or later as the foreskin is retracted. The true incidence of the anomaly is difficult to determine precisely as some patient never come to medical attention but is felt to under 5% of all cases of hypospadias. The purposes of this study are to review the embryology and clinical findings of MIP and then, in light of a personal expe...

  17. The Megameatus, Intact Prepuce Variant of Hypospadias: Use of the Inframeatal Vascularized Flap for Surgical Correction

    Directory of Open Access Journals (Sweden)

    Marc Cendron

    2018-03-01

    Full Text Available IntroductionThe megameatus intact prepuce (MIP variant of hypospadias is a rare variant of hypospadias that is diagnosed either early at the time of circumcision or later as the foreskin is retracted. The true incidence of the anomaly is difficult to determine precisely as some patient never come to medical attention but is felt to under 5% of all cases of hypospadias. The purposes of this study are to review the embryology and clinical findings of MIP and then, in light of a personal experience, present a series of patients evaluated for MIP who were treated with a modification of the Mathieu technique.Materials and methodsA PubMed search of all articles in the MIP variant of hypospadias was carried out followed by an exhaustive review of the literature. The charts of all patients evaluated and treated at Boston Children’s Hospital by MC between 2007 and 2017 were reviewed retrospectively. The patients were divided into two groups: those who underwent the standard procedure and those who underwent a repair using a modification of the Mathieu procedure using an inframeatal flap.ResultsThe embryologic explanation of the MIP variant is not clear but failure of the distal, glanular portion of the urethra to tubularize results in spectrum of abnormality characterized by a deep glanular groove and an abnormal opening of the urethra anywhere from the mid-glans to a subcoronal location. Surgical repair is complicated by a wide distal urethra which may be injured if not properly identified. Overall good outcomes were noted with one patient experiencing a urethra cutaneous fistula in the first group and one patient having a mild glans dehiscence in the second.ConclusionThe MIP variant of hypospadias is a rare variant of hypospadias that presents as a spectrum of urethral anomaly. Surgical repair may not always be necessary but if surgical repair is carried out, the Mathieu technique modification may offer better anatomic delineation of the urethra and will provide an extra layer of tissue to cover the reconstructed urethra. Low complication rates should be expected with adequate functional outcome such as a normal urinary stream. In addition, criteria for selecting patients for surgical repair are provided.

  18. The Megameatus, Intact Prepuce Variant of Hypospadias: Use of the Inframeatal Vascularized Flap for Surgical Correction.

    Science.gov (United States)

    Cendron, Marc

    2018-01-01

    The megameatus intact prepuce (MIP) variant of hypospadias is a rare variant of hypospadias that is diagnosed either early at the time of circumcision or later as the foreskin is retracted. The true incidence of the anomaly is difficult to determine precisely as some patient never come to medical attention but is felt to under 5% of all cases of hypospadias. The purposes of this study are to review the embryology and clinical findings of MIP and then, in light of a personal experience, present a series of patients evaluated for MIP who were treated with a modification of the Mathieu technique. A PubMed search of all articles in the MIP variant of hypospadias was carried out followed by an exhaustive review of the literature. The charts of all patients evaluated and treated at Boston Children's Hospital by MC between 2007 and 2017 were reviewed retrospectively. The patients were divided into two groups: those who underwent the standard procedure and those who underwent a repair using a modification of the Mathieu procedure using an inframeatal flap. The embryologic explanation of the MIP variant is not clear but failure of the distal, glanular portion of the urethra to tubularize results in spectrum of abnormality characterized by a deep glanular groove and an abnormal opening of the urethra anywhere from the mid-glans to a subcoronal location. Surgical repair is complicated by a wide distal urethra which may be injured if not properly identified. Overall good outcomes were noted with one patient experiencing a urethra cutaneous fistula in the first group and one patient having a mild glans dehiscence in the second. The MIP variant of hypospadias is a rare variant of hypospadias that presents as a spectrum of urethral anomaly. Surgical repair may not always be necessary but if surgical repair is carried out, the Mathieu technique modification may offer better anatomic delineation of the urethra and will provide an extra layer of tissue to cover the reconstructed urethra. Low complication rates should be expected with adequate functional outcome such as a normal urinary stream. In addition, criteria for selecting patients for surgical repair are provided.

  19. Vascular calcifications on the preoperative radiograph: harbinger of tourniquet failure in patients undergoing total knee arthroplasty?

    Energy Technology Data Exchange (ETDEWEB)

    Woelfle-Roos, Julia Verena; Dautel, Laura; Bieger, Ralf; Reichel, Heiko [University of Ulm, Department of Orthopaedic Surgery, Ulm (Germany); Mayer, Benjamin [University of Ulm, Institute of Epidemiology and Medical Biometrics, Ulm (Germany); Woelfle, Klaus-Dieter [Klinikum Augsburg, Vascular Surgery Division, Surgical Center, Augsburg (Germany)

    2017-09-15

    Vascular calcifications on the preoperative radiograph of patients scheduled for total knee arthroplasty (TKA) often give rise to concern, as their clinical relevance remains uncertain. The aim of this study was to investigate whether these vascular calcifications - especially medial artery calcifications (MACs), which increase arterial stiffness - were associated with tourniquet failure and thus with increased intraoperative blood loss. A total of 765 patients who underwent primary TKA with a tourniquet (cuff pressure 350 mmHg) between 2009 and 2011 were screened for vascular calcifications on the preoperative radiograph. Vascular calcifications were classified into intimal and medial artery calcifications. Intraoperative blood loss of patients with and without MAC was compared, and a mixed linear regression model was used to adjust for the presence of several confounding factors (e.g., obesity, operating time). None of the 50 (6.5%) patients with MAC showed signs of tourniquet failure. Intraoperative blood loss of patients with MAC was not significantly elevated compared to the overall study group (p = 0.592) even when corrected for the presence of several confounding factors. We found no evidence that vascular calcifications seen on the preoperative radiograph might be associated with tourniquet failure. However, surgeons should be aware of this possibility as tourniquet failure might become more common considering the ongoing trend toward minimizing cuff pressures. (orig.)

  20. Assessment of public knowledge about the scope of practice of vascular surgeons.

    Science.gov (United States)

    Farber, Alik; Long, Brandon M; Lauterbach, Stephen R; Bohannon, Todd; Siegal, Carolyn L

    2010-03-01

    During the past decade, there has been a sharp increase in the number of vascular procedures performed in the United States. Due to the increase in the size of the aging population, this trend is predicted to continue. Despite this, general public knowledge about vascular surgery appears low. This gap may significantly affect the success of vascular surgery as a specialty. To objectively define knowledge about vascular surgery, we administered a questionnaire to both a sample of the general population and medical students. The Vascular Surgery Knowledge Questionnaire (VSQ), a 58-item multiple choice survey, was designed to assess knowledge about the field of vascular surgery, including types of procedures commonly performed, presenting illnesses, training, and financial compensation. VSQ was tested for reliability and validity. It was administered to a sample of the general population (GP) and first year medical students (MS) via a random digit dial telephone survey and a paper-based survey, respectively. VSQ Score was derived by calculating the percent of questions from the 38-item, non-demographic part of the questionnaire answered correctly and expressed in numerical form. The maximum score possible was 100. Statistical analysis was used to assess differences in VSQ scores. Two hundred GP and 160 MS subjects completed the questionnaire. The mean VSQ score for GP and MS groups was 54 and 67 (P .05). These findings support our hypothesis that there is a significant knowledge deficit among both the general population and medical students about the field of vascular surgery. This has protean implications for the future of our specialty and public health in the United States.

  1. Transscleral diode photocoagulation of large retinal and choroidal vascular lesions.

    Directory of Open Access Journals (Sweden)

    Yun Feng

    Full Text Available BACKGROUND: Transscleral retinal photocoagulation with a diode laser is used in glaucoma refractory to medical and surgical treatment. Our main research question was how the technique performed in large vascular lesions associated with hemangiomas of the retina and choroid. METHODOLOGY/CLINICAL FINDINGS: Patient charts were retrieved from the hospital files for patients who underwent the procedure and were followed for at least 24 months. Five patients (6 eyes fit the criteria. Cases included Von Hippel's disease (2 eyes, Coats' disease (1 eye and choroidal hemangioma (3 cases. Transscleral diode laser treatment was performed under retrobulbar and topical anesthesia with a retinopexy probe (IRIS DioPexy, IRIS Medical Instruments, Mountain View, CA applied transsclerally under indirect ophthalmoscope visualization. We found an improvement in best-corrected visual acuity at 24 months postoperatively. CONCLUSIONS/SIGNIFICANCE: Transscleral photocoagulation may have a clinical application in these diseases as an alternate to the high cost of photodynamic therapy with photosensitizing agents.

  2. Virtual reality: emerging role of simulation training in vascular access.

    Science.gov (United States)

    Davidson, Ingemar J A; Lok, Charmaine; Dolmatch, Bart; Gallieni, Maurizio; Nolen, Billy; Pittiruti, Mauro; Ross, John; Slakey, Douglas

    2012-11-01

    Evolving new technologies in vascular access mandate increased attention to patient safety; an often overlooked yet valuable training tool is simulation. For the end-stage renal disease patient, simulation tools are effective for all aspects of creating access for peritoneal dialysis and hemodialysis. Based on aviation principles, known as crew resource management, we place equal emphasis on team training as individual training to improve interactions between team members and systems, cumulating in improved safety. Simulation allows for environmental control and standardized procedures, letting the trainee practice and correct mistakes without harm to patients, compared with traditional patient-based training. Vascular access simulators range from suture devices, to pressurized tunneled conduits for needle cannulation, to computer-based interventional simulators. Simulation training includes simulated case learning, root cause analysis of adverse outcomes, and continual update and refinement of concepts. Implementation of effective human to complex systems interaction in end-stage renal disease patients involves a change in institutional culture. Three concepts discussed in this article are as follows: (1) the need for user-friendly systems and technology to enhance performance, (2) the necessity for members to both train and work together as a team, and (3) the team assigned to use the system must test and practice it to a proficient level before safely using the system on patients. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Food systems in correctional settings

    DEFF Research Database (Denmark)

    Smoyer, Amy; Kjær Minke, Linda

    management of food systems may improve outcomes for incarcerated people and help correctional administrators to maximize their health and safety. This report summarizes existing research on food systems in correctional settings and provides examples of food programmes in prison and remand facilities......Food is a central component of life in correctional institutions and plays a critical role in the physical and mental health of incarcerated people and the construction of prisoners' identities and relationships. An understanding of the role of food in correctional settings and the effective......, including a case study of food-related innovation in the Danish correctional system. It offers specific conclusions for policy-makers, administrators of correctional institutions and prison-food-service professionals, and makes proposals for future research....

  4. CORRECTED MARCH EDITON 2009 F...

    African Journals Online (AJOL)

    User

    Haemorrhoids, symptomatic vascular cushions i.e. engorgement of haemorrhoidal venous plexuses with redundancy of their coverings, are a problem that has plagued man kind since the dawn of civilization. The detailed description of haemorrhoids dates back to Hippocrates, who treated the condition with suppositories, ...

  5. Corrective justice and contract law

    Directory of Open Access Journals (Sweden)

    Martín Hevia

    2010-06-01

    Full Text Available This article suggests that the central aspects of contract law in various jurisdictions can be explained within the idea of corrective justice. The article is divided into three parts. The first part distinguishes between corrective justice and distributive justice. The second part describes contract law. The third part focuses on actions for breach of contract and within that context reflects upon the idea of corrective justice.

  6. Corrective justice and contract law

    OpenAIRE

    Martín Hevia

    2010-01-01

    This article suggests that the central aspects of contract law in various jurisdictions can be explained within the idea of corrective justice. The article is divided into three parts. The first part distinguishes between corrective justice and distributive justice. The second part describes contract law. The third part focuses on actions for breach of contract and within that context reflects upon the idea of corrective justice.

  7. [Localized purpura revealing vascular prosthetic graft infection].

    Science.gov (United States)

    Boureau, A S; Lescalie, F; Cassagnau, E; Clairand, R; Connault, J

    2013-07-01

    Prosthetic graft infection after vascular reconstruction is a rare but serious complication. We report a case of infection occurring late after implantation of an iliofemoral prosthetic vascular graft. The Staphylococcus aureus infection was revealed by vascular purpura localized on the right leg 7 years after implantation of a vascular prosthesis. This case illustrates an uncommonly late clinical manifestation presenting as an acute infection 7 years after the primary operation. In this situation, the presentation differs from early infection, which generally occurs within the first four postoperative months. Diagnosis and treatment remain a difficult challenge because prosthetic graft infection is a potentially life-threatening complication. Morbidity and mortality rates are high. Here we detail specific aspects of the clinical and radiological presentation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  8. Vascular function in health, hypertension, and diabetes

    DEFF Research Database (Denmark)

    Nyberg, Michael Permin; Gliemann, Lasse; Hellsten, Ylva

    2015-01-01

    muscle, which can affect muscle function. Central aspects in the vascular impairments are alterations in the formation of prostacyclin, the bioavailability of NO and an increased formation of vasoconstrictors and reactive oxygen species (ROS). Regular physical activity effectively improves vascular......, the increase in muscle blood flow required for oxygen supply during exercise is achieved through a substantial increase in vasodilators locally formed in the active muscle tissue that overcome the vasoconstrictor signals. Most of the vasodilator signals are mediated via endothelial cells, which lead...... to the formation of vasodilators such as nitric oxide (NO) and prostacyclin. In essential hypertension and type II diabetes, the endothelial function and regulation of vascular tone is impaired with consequent increases in peripheral vascular resistance and inadequate regulation of oxygen supply to the skeletal...

  9. Human genetics of diabetic vascular complications

    Indian Academy of Sciences (India)

    Abstract. Diabetic vascular complications (DVC) affecting several important organ systems of human body such as the ..... cohort with nominal significance, and a recent meta-analysis ..... Whereas it is generally thought that lysine acetylation is.

  10. Incorporating simulation in vascular surgery education.

    Science.gov (United States)

    Bismuth, Jean; Donovan, Michael A; O'Malley, Marcia K; El Sayed, Hosam F; Naoum, Joseph J; Peden, Eric K; Davies, Mark G; Lumsden, Alan B

    2010-10-01

    The traditional apprenticeship model introduced by Halsted of "learning by doing" may just not be valid in the modern practice of vascular surgery. The model is often criticized for being somewhat unstructured because a resident's experience is based on what comes through the "door." In an attempt to promote uniformity of training, multiple national organizations are currently delineating standard curricula for each trainee to govern the knowledge and cases required in a vascular residency. However, the outcomes are anything but uniform. This means that we graduate vascular specialists with a surprisingly wide spectrum of abilities. Use of simulation may benefit trainees in attaining a level of technical expertise that will benefit themselves and their patients. Furthermore, there is likely a need to establish a simulation-based certification process for graduating trainees to further ascertain minimum technical abilities. Copyright © 2010 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

  11. Audit of the Danish national vascular database

    DEFF Research Database (Denmark)

    Levi-Mazloum, Niels Donald; Jensen, L P; Schroeder, T V

    1996-01-01

    The accuracy of data contained in the Danish vascular database was compared with the case notes. A total of 100 case notes were reviewed for 11 pertinent variables in the database. A high error rate ranging from 2 to 34% was found. Also, approximately 10% of patients had never been entered into t...... into the vascular database. Further improvement of the Danish vascular database is necessary for its use as basis for reporting results.......The accuracy of data contained in the Danish vascular database was compared with the case notes. A total of 100 case notes were reviewed for 11 pertinent variables in the database. A high error rate ranging from 2 to 34% was found. Also, approximately 10% of patients had never been entered...

  12. Vascular adaptation to physical inactivity in humans.

    NARCIS (Netherlands)

    Bleeker, M.W.P.

    2006-01-01

    This thesis presents studies on vascular adaptation to physical inactivity and deconditioning. Although it is clear that physical inactivity is an important risk factor for cardiovascular disease, the underlying physiological mechanisms have not yet been elucidated. In contrast to physical

  13. Extracellular Matrix Molecules Facilitating Vascular Biointegration

    Directory of Open Access Journals (Sweden)

    Martin K.C. Ng

    2012-08-01

    Full Text Available All vascular implants, including stents, heart valves and graft materials exhibit suboptimal biocompatibility that significantly reduces their clinical efficacy. A range of biomolecules in the subendothelial space have been shown to play critical roles in local regulation of thrombosis, endothelial growth and smooth muscle cell proliferation, making these attractive candidates for modulation of vascular device biointegration. However, classically used biomaterial coatings, such as fibronectin and laminin, modulate only one of these components; enhancing endothelial cell attachment, but also activating platelets and triggering thrombosis. This review examines a subset of extracellular matrix molecules that have demonstrated multi-faceted vascular compatibility and accordingly are promising candidates to improve the biointegration of vascular biomaterials.

  14. Lipidomics in vascular health: current perspectives.

    Science.gov (United States)

    Kolovou, Genovefa; Kolovou, Vana; Mavrogeni, Sophie

    2015-01-01

    Identifying the mechanisms that convert a healthy vascular wall to an atherosclerotic wall is of major importance since the consequences may lead to a shortened lifespan. Classical risk factors (age, smoking, obesity, diabetes mellitus, hypertension, and dyslipidemia) may result in the progression of atherosclerotic lesions by processes including inflammation and lipid accumulation. Thus, the evaluation of blood lipids and the full lipid complement produced by cells, organisms, or tissues (lipidomics) is an issue of importance. In this review, we shall describe the recent progress in vascular health research using lipidomic advances. We will begin with an overview of vascular wall biology and lipids, followed by a short analysis of lipidomics. Finally, we shall focus on the clinical implications of lipidomics and studies that have examined lipidomic approaches and vascular health.

  15. Lower limb vascular dysfunction in cyclists

    Directory of Open Access Journals (Sweden)

    Thiago Ayala Melo Di Alencar

    2013-06-01

    Full Text Available Sports-related vascular insufficiency affecting the lower limbs is uncommon, and early signs and symptoms can be confused with musculoskeletal injuries. This is also the case among professional cyclists, who are always at the threshold between endurance and excess training. The aim of this review was to analyze the occurrence of vascular disorders in the lower limbs of cyclists and to discuss possible etiologies. Eighty-five texts, including papers and books, published from 1950 to 2012, were used. According to the literature reviewed, some cyclists receive a late diagnosis of vascular dysfunction due to a lack of familiarity of the medical team with this type of dysfunction. Data revealed that a reduced blood flow in the external iliac artery, especially on the left, is much more common than in the femoral and popliteal arteries, and that vascular impairment is responsible for the occurrence of early fatigue and reduced performance in cycling.

  16. Realization of a tool as an help for piloting during accidental situation, conceiving of a procedure of state correction in compliance with safety constraints

    International Nuclear Information System (INIS)

    Monribot, A.

    1996-01-01

    The tool we have developed acts as an help for piloting nuclear fuel reprocessing working units. After the localisation of a malfunction, it can generate a series of correcting moves in order to reach a defined level of security, in absolute compliance with all the safety regulations. These operations are created by an iterative algorithm, which determines at each step: the best suited operating parameter for the correction, the range and time of action of this correction. This algorithm is composed of tow modules relying respectively on a certified numerical model to stimulate the process and on the experimental design technique. The first module uses a numerical model to perform a sensibility analysis determining the most accurate correcting parameters. The variable allowing reliability of this analysis is guaranteed, for any current situation of the process, by an exhaustive study of the operating parameters and the use of a mathematical response determining the state of the process. The second module uses the experimental design to reduce the model, then it adjusts the correction range with this reduced model. This module automatically adjusts the total number of experimental designs as a function of the error of the responses. In order to minimise the total number of experiments, thus the global computing time, we have checked different types of experimental designs: DOELHERT's uniform lattices and second order centered factorial experimental design. These last ones were proved to be more efficient. The correcting solutions proposed by our tool for the major classical malfunctions of the nuclear fuel reprocessing plant working units were certified by the specialists of the process. (author)

  17. Laser-assisted vascular anastomosis

    Science.gov (United States)

    Kao, Race L.; Tsao-Wu, George; Magovern, George J.

    1990-06-01

    The milliwatt CO2 laser and a thermal activated binding compound (20% serum albumin) were used for microvascular anastomoses. Under general anesthesia, the femoral arteries (0.7 to 1.0 mm diameter) of 6 rats were isolated. After the left femoral artery in each rat was clamped and transected, the vessel was held together with 3 equidistant 10-0 Xomed sutures. The cut edges were coated 3 to 4 times with the albumin solution and sealed with the CO2 laser (power density = 120 W/cm2). The binding compound solidified to a translucent tensile substance which supported the anastomosis until self healing and repair were achieved. The right femoral artery was used as sham operated control. Complete hemostasis and patency were observed in every case immediately and at 1, 3, and 6 months following surgery. The binding compound absorbed most of the laser energy thus minimizing thermal injury to the underlying tissue. Mongrel dogs weighing 28 to 33 kg were anesthetized and prepared for sterile surgical procedures. In 5 dogs, the femoral and jugular veins were exposed, transected, and anastomosed using a CO2 laser (Sharplan 1040) with the binding compound. In another 12 dogs, cephalic veins were isolated and used for aortocoronary artery bypass procedures. The Sharplan 1040 CO2 laser and 20% albumin solution were utilized to complete the coronary anastomoses in 6 dogs, and 6 dogs were used as controls by suturing the vessels. Again, hemostasis, patency, and minimal tissue damage were observed immediately and 6 weeks after the procedures. Improved surgical results, reduced operating time, minimized tissue damage, and enhanced anastomotic integrity are the advantages of laser assisted vascular anastomosis with a thermal activated binding compound.

  18. The vascular surgery workforce: a survey of consultant vascular surgeons in the UK, 2014.

    Science.gov (United States)

    Harkin, D W; Beard, J D; Shearman, C P; Wyatt, M G

    2015-04-01

    The purpose of this study was to describe the demographics, training, and practice characteristics of consultant vascular surgeons across the UK to provide an assessment of current, and inform future prediction of workforce needs. A questionnaire was developed using a modified Delphi process to generate questionnaire items. The questionnaire was emailed to all consultant vascular surgeons (n = 450) in the UK who were members of the Vascular Society of Great Britain & Ireland. 352 consultant vascular surgeons from 95 hospital trusts across the UK completed the survey (78% response rate). The mean age was 50.6 years old, the majority (62%) were mid-career, but 24% were above the age of 55. Currently, 92% are men and only 8% women. 93% work full-time, with 60% working >50 hours, and 21% working >60 hours per week. The average team was 5 to 6 (range 2-10) vascular surgeons, with 23% working in a large team of ≥8. 17% still work in small teams of ≤3. Over 90% of consultant vascular surgeons perform the major index vascular surgery procedures (aneurysm repair, carotid endarterectomy, infra-inguinal bypass, amputation). While 84% perform standard endovascular abdominal aortic aneurysm repair (EVAR), <50% perform more complex endovascular aortic therapy. The majority of vascular surgeons "like their job" (85%) and are "satisfied" (69%) with their job. 34% of consultant vascular surgeons indicated they were "extremely likely" to retire within the next 10 years. This study provides the first detailed analysis of the new specialty of vascular surgery as practiced in the UK. There is a need to plan for a significant expansion in the consultant vascular surgeon workforce in the UK over the next 10 years to maintain the status quo. Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  19. Biomimicry, vascular restenosis and coronary stents.

    Science.gov (United States)

    Schwartz, R S; van der Giessen, W J; Holmes, D R

    1998-01-01

    Biomimicry is in its earliest stages and is being considered in the realm of tissue engineering. If arterial implants are to limit neointimal thickening, purely passive structures cannot succeed. Bioactivity must be present, either by pharmacologic intervention or by fabricating a 'living stent' that contains active cellular material. As tissue engineering evolves, useful solutions will emerge from applying this knowledge directly to vascular biologic problems resulting from angioplasty, stenting, and vascular prosthesis research.

  20. The current role of vascular stents.

    Science.gov (United States)

    Busquet, J

    1993-09-01

    The limitations of percutaneous balloon angioplasty have favoured the development and the use of vascular endoprostheses or stents. These thin-walled metal devices maintain after expansion, an optimal and constant diameter for the vascular lumen. Restenosis, dissection, abrupt closure, residual stenosis or re-opened total occlusion represent appropriate indications for stenting. A large experience with non-coronary application of stents is currently available in iliac, femoro-popliteal and renal arteries, aorta, large veins.

  1. Vascular colitis: a report of two cases

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan Il; Han, Chang Yul; Han, Man Chung; Choo, Dong Woon [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1973-04-15

    The authors report two cases of vascular colitis in Korean with a review of literature. Case I, 20 years old male had severe abdominal pain and bloody diarrhea. Case II was 57 years old male and complained severe abdominal pain. Barium enema colon study on each cases disclosed typical thumbprinting appearance of involved segment. Predisposing factor in case I appeared to be anaphylactoid purpura, and in case II distal obstruction due to adenocarcinoma. The mechanism of vascular was briefly discussed.

  2. Robotic vascular resections during Whipple procedure.

    Science.gov (United States)

    Allan, Bassan J; Novak, Stephanie M; Hogg, Melissa E; Zeh, Herbert J

    2018-01-01

    Indications for resection of pancreatic cancers have evolved to include selected patients with involvement of peri-pancreatic vascular structures. Open Whipple procedures have been the standard approach for patients requiring reconstruction of the portal vein (PV) or superior mesenteric vein (SMV). Recently, high-volume centers are performing minimally invasive Whipple procedures with portovenous resections. Our institution has performed seventy robotic Whipple procedures with concomitant vascular resections. This report outlines our technique.

  3. Effects of ouabain on vascular reactivity

    Directory of Open Access Journals (Sweden)

    Vassallo D.V.

    1997-04-01

    Full Text Available Ouabain is an endogenous substance occurring in the plasma in the nanomolar range, that has been proposed to increase vascular resistance and induce hypertension. This substance acts on the a-subunit of Na+,K+-ATPase inhibiting the Na+-pump activity. In the vascular smooth muscle this effect leads to intracellular Na+ accumulation that reduces the activity of the Na+/Ca2+ exchanger and to an increased vascular tone. It was also suggested that circulating ouabain, even in the nanomolar range, sensitizes the vascular smooth muscle to vasopressor substances. We tested the latter hypothesis by studying the effects of ouabain in the micromolar and nanomolar range on phenylephrine (PE-evoked pressor responses. The experiments were performed in normotensive and hypertensive rats in vivo, under anesthesia, and in perfused rat tail vascular beds. The results showed that ouabain pretreatment increased the vasopressor responses to PE in vitro and in vivo. This sensitization after ouabain treatment was also observed in hypertensive animals which presented an enhanced vasopressor response to PE in comparison to normotensive animals. It is suggested that ouabain at nanomolar concentrations can sensitize vascular smooth muscle to vasopressor stimuli possibly contributing to increased tone in hypertension

  4. 3D bioprinting for vascularized tissue fabrication

    Science.gov (United States)

    Richards, Dylan; Jia, Jia; Yost, Michael; Markwald, Roger; Mei, Ying

    2016-01-01

    3D bioprinting holds remarkable promise for rapid fabrication of 3D tissue engineering constructs. Given its scalability, reproducibility, and precise multi-dimensional control that traditional fabrication methods do not provide, 3D bioprinting provides a powerful means to address one of the major challenges in tissue engineering: vascularization. Moderate success of current tissue engineering strategies have been attributed to the current inability to fabricate thick tissue engineering constructs that contain endogenous, engineered vasculature or nutrient channels that can integrate with the host tissue. Successful fabrication of a vascularized tissue construct requires synergy between high throughput, high-resolution bioprinting of larger perfusable channels and instructive bioink that promotes angiogenic sprouting and neovascularization. This review aims to cover the recent progress in the field of 3D bioprinting of vascularized tissues. It will cover the methods of bioprinting vascularized constructs, bioink for vascularization, and perspectives on recent innovations in 3D printing and biomaterials for the next generation of 3D bioprinting for vascularized tissue fabrication. PMID:27230253

  5. Vascular retraction driven by matrix softening

    Science.gov (United States)

    Valentine, Megan

    We recently discovered we can directly apply physical forces and monitor the downstream responses in a living organism in real time through manipulation of the blood vessels of a marine organism called, Botryllus schlosseri. The extracellular matrix (ECM) plays a key role in regulating vascular growth and homeostasis in Botryllus,a basal chordate which has a large, transparent extracorporeal vascular network that can encompass areas >100 cm2. We have determined that lysyl oxidase 1 (LOX1), which is responsible for cross-linking collagen, is expressed in all vascular cells and is critically important for vascular maintenance. Inhibition of LOX1 activity in vivo by the addition of a specific inhibitor, ß-aminopropionitrile (BAPN), caused a rapid, global regression of the entire vascular bed, with some vessels regressing >10 mm within 16 hrs. In this talk, I will discuss the molecular and cellular origins of this systemic remodeling event, which hinges upon the ability of the vascular cells to sense and respond to mechanical signals, while introducing this exciting new model system for studies of biological physics and mechanobiology. Collaborators: Anthony DeTomaso, Delany Rodriguez, Aimal Khankhel (UCSB).

  6. [Vascular aging, arterial hypertension and physical activity].

    Science.gov (United States)

    Schmidt-Trucksäss, A; Weisser, B

    2011-11-01

    The present review delineates the significance of intima-media-thickness, arterial stiffness and endothelial function for vascular aging. There is profound evidence for an increase in intima-media-thickness and vascular stiffness not only during healthy aging but induced also by cardiovascular risk factors. There is a central role of arterial hypertension for this progression in both structural factors. In addition, both parameters are strongly associated with cardiovascular risk. Endothelial function measured as postischemic flow-mediated vasodilatation is a functional parameter which is decreased both in healthy aging and by cardiovascular risk factors. Physical activity modifies the influence of aging and risk factors on endothelial function. A positive influence of endurance exercise on vascular stiffness and endothelial function has been demonstrated in numerous studies. In long-term studies, regular physical activity has been shown to reduce the progression of intima-media-thickness. Thus, arterial hypertension accelerates vascular aging, while physical activity has a positive influence on a variety of vascular parameters associated with vascular aging. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Vascular Adventitia Calcification and Its Underlying Mechanism.

    Directory of Open Access Journals (Sweden)

    Na Li

    Full Text Available Previous research on vascular calcification has mainly focused on the vascular intima and media. However, we show here that vascular calcification may also occur in the adventitia. The purpose of this work is to help elucidate the pathogenic mechanisms underlying vascular calcification. The calcified lesions were examined by Von Kossa staining in ApoE-/- mice which were fed high fat diets (HFD for 48 weeks and human subjects aged 60 years and older that had died of coronary heart disease, heart failure or acute renal failure. Explant cultured fibroblasts and smooth muscle cells (SMCswere obtained from rat adventitia and media, respectively. After calcification induction, cells were collected for Alizarin Red S staining. Calcified lesions were observed in the aorta adventitia and coronary artery adventitia of ApoE-/-mice, as well as in the aorta adventitia of human subjects examined. Explant culture of fibroblasts, the primary cell type comprising the adventitia, was successfully induced for calcification after incubation with TGF-β1 (20 ng/ml + mineralization media for 4 days, and the phenotype conversion vascular adventitia fibroblasts into myofibroblasts was identified. Culture of SMCs, which comprise only a small percentage of all cells in the adventitia, in calcifying medium for 14 days resulted in significant calcification.Vascular calcification can occur in the adventitia. Adventitia calcification may arise from the fibroblasts which were transformed into myofibroblasts or smooth muscle cells.

  8. Patterns of peripheral vascular diseases at Muhimbili National hospital

    African Journals Online (AJOL)

    diseases) and HIV- vasculitis. A total of 97 patients (63%) were surgically treated. Conclusion: Shortage of vascular surgeons and facilities in our. Country needs to be sorted out to save life to these patients with vascular disorders. Key Words: Peripheral Vascular Diseases, and Shortage of Vascular Services in Tanzania.

  9. Lung irradiation induces pulmonary vascular remodelling resembling pulmonary arterial hypertension

    NARCIS (Netherlands)

    Ghobadi, G.; Bartelds, B.; van der Veen, S. J.; Dickinson, M. G.; Brandenburg, S.; Berger, R. M. F.; Langendijk, J. A.; Coppes, R. P.; van Luijk, P.

    Background Pulmonary arterial hypertension (PAH) is a commonly fatal pulmonary vascular disease that is often diagnosed late and is characterised by a progressive rise in pulmonary vascular resistance resulting from typical vascular remodelling. Recent data suggest that vascular damage plays an

  10. Vascular associated gene variants in patients with preeclampsia

    DEFF Research Database (Denmark)

    Lykke, Jacob A; Bare, Lance A; Olsen, Jørn

    2012-01-01

    Preeclampsia has been linked to subsequent vascular disease with many shared predisposing factors. We investigated the association between severe preeclampsia, and its subtypes, and specific vascular-related polymorphisms.......Preeclampsia has been linked to subsequent vascular disease with many shared predisposing factors. We investigated the association between severe preeclampsia, and its subtypes, and specific vascular-related polymorphisms....

  11. Unpacking Corrections in Mobile Instruction

    DEFF Research Database (Denmark)

    Levin, Lena; Cromdal, Jakob; Broth, Mathias

    2017-01-01

    that the practice of unpacking the local particulars of corrections (i) provides for the instructional character of the interaction, and (ii) is highly sensitive to the relevant physical and mobile contingencies. These findings contribute to the existing literature on the interactional organisation of correction...

  12. Atmospheric correction of satellite data

    Science.gov (United States)

    Shmirko, Konstantin; Bobrikov, Alexey; Pavlov, Andrey

    2015-11-01

    Atmosphere responses for more than 90% of all radiation measured by satellite. Due to this, atmospheric correction plays an important role in separating water leaving radiance from the signal, evaluating concentration of various water pigments (chlorophyll-A, DOM, CDOM, etc). The elimination of atmospheric intrinsic radiance from remote sensing signal referred to as atmospheric correction.

  13. Stress Management in Correctional Recreation.

    Science.gov (United States)

    Card, Jaclyn A.

    Current economic conditions have created additional sources of stress in the correctional setting. Often, recreation professionals employed in these settings also add to inmate stress. One of the major factors limiting stress management in correctional settings is a lack of understanding of the value, importance, and perceived freedom, of leisure.…

  14. Sirtuins, Cell Senescence, and Vascular Aging.

    Science.gov (United States)

    Kida, Yujiro; Goligorsky, Michael S

    2016-05-01

    The sirtuins (SIRTs) constitute a class of proteins with nicotinamide adenine dinucleotide-dependent deacetylase or adenosine diphosphate-ribosyltransferase activity. Seven SIRT family members have been identified in mammals, from SIRT1, the best studied for its role in vascular aging, to SIRT7. SIRT1 and SIRT2 are localized in the nucleus and cytoplasm. SIRT3, SIRT4, and SIRT5 are mitochondrial, and SIRT6 and SIRT7 are nuclear. Extensive studies have clearly revealed that SIRT proteins regulate diverse cell functions and responses to stressors. Vascular aging involves the aging process (senescence) of endothelial and vascular smooth muscle cells. Two types of cell senescence have been identified: (1) replicative senescence with telomere attrition; and (2) stress-induced premature senescence without telomere involvement. Both types of senescence induce vascular cell growth arrest and loss of vascular homeostasis, and contribute to the initiation and progression of cardiovascular diseases. Previous mechanistic studies have revealed in detail that SIRT1, SIRT3, and SIRT6 show protective functions against vascular aging, and definite vascular function of other SIRTs is under investigation. Thus, direct SIRT modulation and nicotinamide adenine dinucleotide stimulation of SIRT are promising candidates for cardiovascular disease therapy. A small number of pilot studies have been conducted to assess SIRT modulation in humans. These clinical studies have not yet provided convincing evidence that SIRT proteins alleviate morbidity and mortality in patients with cardiovascular diseases. The outcomes of multiple ongoing clinical trials are awaited to define the efficacy of SIRT modulators and SIRT activators in cardiovascular diseases, along with the potential adverse effects of chronic SIRT modulation. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  15. Progenitor cells in pulmonary vascular remodeling

    Science.gov (United States)

    Yeager, Michael E.; Frid, Maria G.; Stenmark, Kurt R.

    2011-01-01

    Pulmonary hypertension is characterized by cellular and structural changes in the walls of pulmonary arteries. Intimal thickening and fibrosis, medial hypertrophy and fibroproliferative changes in the adventitia are commonly observed, as is the extension of smooth muscle into the previously non-muscularized vessels. A majority of these changes are associated with the enhanced presence of α-SM-actin+ cells and inflammatory cells. Atypical abundances of functionally distinct endothelial cells, particularly in the intima (plexiform lesions), and also in the perivascular regions, are also described. At present, neither the origin(s) of these cells nor the molecular mechanisms responsible for their accumulation, in any of the three compartments of the vessel wall, have been fully elucidated. The possibility that they arise from either resident vascular progenitors or bone marrow–derived progenitor cells is now well established. Resident vascular progenitor cells have been demonstrated to exist within the vessel wall, and in response to certain stimuli, to expand and express myofibroblastic, endothelial or even hematopoietic markers. Bone marrow–derived or circulating progenitor cells have also been shown to be recruited to sites of vascular injury and to assume both endothelial and SM-like phenotypes. Here, we review the data supporting the contributory role of vascular progenitors (including endothelial progenitor cells, smooth muscle progenitor cells, pericytes, and fibrocytes) in vascular remodeling. A more complete understanding of the processes by which progenitor cells modulate pulmonary vascular remodeling will undoubtedly herald a renaissance of therapies extending beyond the control of vascular tonicity and reduction of pulmonary artery pressure. PMID:22034593

  16. Congenital vascular malformations in scintigraphic evaluation

    International Nuclear Information System (INIS)

    Pilecki, Stanisław; Gierach, Marcin; Gierach, Joanna; Świętaszczyk, Cyprian; Junik, Roman; Lasek, Władysław

    2014-01-01

    Congenital vascular malformations are tumour-like, non-neoplastic lesions caused by disorders of vascular tissue morphogenesis. They are characterised by a normal cell replacement cycle throughout all growth phases and do not undergo spontaneous involution. Here we present a scintigraphic image of familial congenital vascular malformations in two sisters. A 17-years-old young woman with a history of multiple hospitalisations for foci of vascular anomalies appearing progressively in the upper and lower right limbs, chest wall and spleen. A Parkes Weber syndrome was diagnosed based on the clinical picture. Due to the occurrence of new foci of malformations, a whole-body scintigraphic examination was performed. A 12-years-old girl reported a lump in the right lower limb present for approximately 2 years, which was clinically identified as a vascular lesion in the area of calcaneus and talus. Phleboscintigraphy visualized normal radiomarker outflow from the feet via the deep venous system, also observed in the superficial venous system once the tourniquets were released. In static and whole-body examinations vascular malformations were visualised in the area of the medial cuneiform, navicular and talus bones of the left foot, as well as in the projection of right calcaneus and above the right talocrural joint. People with undiagnosed disorders related to the presence of vascular malformations should undergo periodic follow-up to identify lesions that may be the cause of potentially serious complications and to assess the results of treatment. Presented scintigraphic methods may be used for both diagnosing and monitoring of disease progression

  17. Gene transfer therapy in vascular diseases.

    Science.gov (United States)

    McKay, M J; Gaballa, M A

    2001-01-01

    Somatic gene therapy of vascular diseases is a promising new field in modern medicine. Recent advancements in gene transfer technology have greatly evolved our understanding of the pathophysiologic role of candidate disease genes. With this knowledge, the expression of selective gene products provides the means to test the therapeutic use of gene therapy in a multitude of medical conditions. In addition, with the completion of genome sequencing programs, gene transfer can be used also to study the biologic function of novel genes in vivo. Novel genes are delivered to targeted tissue via several different vehicles. These vectors include adenoviruses, retroviruses, plasmids, plasmid/liposomes, and oligonucleotides. However, each one of these vectors has inherent limitations. Further investigations into developing delivery systems that not only allow for efficient, targeted gene transfer, but also are stable and nonimmunogenic, will optimize the clinical application of gene therapy in vascular diseases. This review further discusses the available mode of gene delivery and examines six major areas in vascular gene therapy, namely prevention of restenosis, thrombosis, hypertension, atherosclerosis, peripheral vascular disease in congestive heart failure, and ischemia. Although we highlight some of the recent advances in the use of gene therapy in treating vascular disease discovered primarily during the past two years, many excellent studies published during that period are not included in this review due to space limitations. The following is a selective review of practical uses of gene transfer therapy in vascular diseases. This review primarily covers work performed in the last 2 years. For earlier work, the reader may refer to several excellent review articles. For instance, Belalcazer et al. (6) reviewed general aspects of somatic gene therapy and the different vehicles used for the delivery of therapeutic genes. Gene therapy in restenosis and stimulation of

  18. Adiposity, adipocytokines & microvesicles in the etiology of vascular disease

    OpenAIRE

    Kanhai, D.A.N.I.S.

    2013-01-01

    Vascular disease, in this thesis the terms vascular and cardiovascular are used interchangeably, is the number 1 cause of death worldwide. In 2008, 30% of all mortality had a vascular origin. Vascular mortality rates after a first manifestation of vascular disease are decreasing in Western society, which is attributable to better disease awareness, better preventive strategies and better healthcare systems. As mortality rates are decreasing, the number of patients surviving their first vascul...

  19. Open and endovascular aneurysm repair in the Society for Vascular Surgery Vascular Quality Initiative.

    Science.gov (United States)

    Spangler, Emily L; Beck, Adam W

    2017-12-01

    The Society for Vascular Surgery Vascular Quality Initiative is a patient safety organization and a collection of procedure-based registries that can be utilized for quality improvement initiatives and clinical outcomes research. The Vascular Quality Initiative consists of voluntary participation by centers to collect data prospectively on all consecutive cases within specific registries which physicians and centers elect to participate. The data capture extends from preoperative demographics and risk factors (including indications for operation), through the perioperative period, to outcomes data at up to 1-year of follow-up. Additionally, longer-term follow-up can be achieved by matching with Medicare claims data, providing long-term longitudinal follow-up for a majority of patients within the Vascular Quality Initiative registries. We present the unique characteristics of the Vascular Quality Initiative registries and highlight important insights gained specific to open and endovascular abdominal aortic aneurysm repair. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Preparation and features of polycaprolactone vascular grafts with the incorporated vascular endothelial growth factor

    Energy Technology Data Exchange (ETDEWEB)

    Sevostyanova, V. V., E-mail: sevostyanova.victoria@gmail.com; Khodyrevskaya, Y. I.; Glushkova, T. V.; Antonova, L. V.; Kudryavtseva, Y. A.; Barbarash, O. L.; Barbarash, L. S. [Research Institute for Complex Issues of Cardiovascular Diseases, Kemerovo (Russian Federation)

    2015-10-27

    The development of tissue-engineered small-diameter vascular grafts is an urgent issue in cardiovascular surgery. In this study, we assessed how the incorporation of the vascular endothelial growth factor (VEGF) affects morphological and mechanical properties of polycaprolactone (PCL) vascular grafts along with its release kinetics. Vascular grafts were prepared using two-phase electrospinning. In pursuing our aims, we performed scanning electron microscopy, mechanical testing, and enzyme-linked immunosorbent assay. Our results demonstrated the preservation of a highly porous structure and improvement of PCL/VEGF scaffold mechanical properties as compared to PCL grafts. A prolonged VEGF release testifies the use of this construct as a scaffold for tissue-engineered vascular grafts.

  1. Effects of PPARγ ligands on vascular tone.

    Science.gov (United States)

    Salomone, Salvatore; Drago, Filippo

    2012-06-01

    Peroxisome Proliferator-Activated Receptor γ (PPARγ), originally described as a transcription factor for genes of carbohydrate and lipid metabolism, has been more recently studied in the context of cardiovascular pathophysiology. Here, we review the available data on PPARγ ligands as modulator of vascular tone. PPARγ ligands include: thiazolidinediones (used in the treatment of type 2 diabetes mellitus), glitazars (bind and activate both PPARγ and PPARα), and other experimental drugs (still in development) that exploit the chemistry of thiazolidinediones as a scaffold for PPARγ-independent pharmacological properties. In this review, we examine both short (mostly from in vitro data)- and long (mostly from in vivo data)-term effects of PPARγ ligands that extend from PPARγ-independent vascular effects to PPARγ-dependent gene expression. Because endothelium is a master regulator of vascular tone, we have attempted to differentiate between endothelium-dependent and endothelium-independent effects of PPARγ ligands. Based on available data, we conclude that PPARγ ligands appear to influence vascular tone in different experimental paradigms, most often in terms of vasodilatation (potentially increasing blood flow to some tissues). These effects on vascular tone, although potentially beneficial, must be weighed against specific cardiovascular warnings that may apply to some drugs, such as rosiglitazone.

  2. Insulin resistance: vascular function and exercise

    Directory of Open Access Journals (Sweden)

    Moon-Hyon Hwang

    2016-09-01

    Full Text Available Insulin resistance associated with metabolic syndrome and Type 2 diabetes mellitus is an epidemic metabolic disorder, which increases the risk of cardiovascular complications. Impaired vascular endothelial function is an early marker for atherosclerosis, which causes cardiovascular complications. Both experimental and clinical studies indicate that endothelial dysfunction in vasculatures occurs with insulin resistance. The associated physiological mechanisms are not fully appreciated yet, however, it seems that augmented oxidative stress, a physiological imbalance between oxidants and antioxidants, in vascular cells is a possible mechanism involved in various vascular beds with insulin resistance and hyperglycemia. Regardless of the inclusion of resistance exercise, aerobic exercise seems to be beneficial for vascular endothelial function in both large conduit and small resistance vessels in both clinical and experimental studies with insulin resistance. In clinical cases, aerobic exercise over 8 weeks with higher intensity seems more beneficial than the cases with shorter duration and lower intensity. However, more studies are needed in the future to elucidate the physiological mechanisms by which vascular endothelial function is impaired in insulin resistance and improved with aerobic exercise.

  3. Vascular trauma: selected historical reflections from the

    Directory of Open Access Journals (Sweden)

    Rich Norman M

    2011-04-01

    Full Text Available 【Abstract】In the spirit of international exchanges of knowledge with colleagues from all over the world, who are interested in the care and treatment of vascular trauma, we offer selected historical reflections from the western world on vascular trauma. Whereas there are a number of key individuals and a variety of events that are important to us in our writing, we know essentially nothing about what is written by other cultures and, particularly, the Chinese. It is well recognized around the world that Chinese surgeons are among the first to be highly successful in re-plantation of severed extremities, repairing both injured arteries and veins. Also, we recognize that there are contributions in other parts of the world, which are not well known to us collectively. Contributions from the Arabic speaking part of the world come to mind because there is periodic brief reference. We offer our perspective hoping that there will be one or more Chinese surgeons who will offer us the benefit of sharing their perspective on important historical contributions to the managing of vascular trauma outside of the western world, and, particularly, the English speaking literature. Once again, we encourage our colleagues in the Arabic speaking world to provide us with their perspective of the development and management of vascular trauma. Key words: Vascular system injuries; History; Western world; International educational exchange

  4. Arteriographic evaluation, in the perispheric vascular trauma

    International Nuclear Information System (INIS)

    Patino, Jairo Hernando; Granados, Ana Maria; Lopera B, Jorge; Prada W, Angela Maria

    1993-01-01

    136 patients were angiographically studied under the suspicion of perispheric vascular lesion submitted to the radiology department of the San Vicente de Paul University Hospital (H.U.S.VP.) Medellin Colombia. The majority of the patients were young with wounds caused by gunshots (79.4%). the must frequent angiographic indication was the proximity of the wound to a vascular path (44.5%). 63% of the patients with angiography indicative of abnormality needed surgery from which 21% were because of the proximity of the wound to a vascular path and 76% because of the mayor findings when admitted to the hospital. the possible complications as a result of the angiographic procedure were revised only find inc two mayor reactions to the contrast media. there were no late complications. Angiography is highlighting sensitive (100%) specific (98.5%) and secure in the evaluation of patients with perispheric vascular trauma. Due to the high number of false negatives when the physical examination is performed, every patient with a wound near a vascular path must be evaluated angiographically

  5. Endothelial dysfunction in metabolic and vascular disorders.

    Science.gov (United States)

    Polovina, Marija M; Potpara, Tatjana S

    2014-03-01

    Vascular endothelium has important regulatory functions in the cardiovascular system and a pivotal role in the maintenance of vascular health and metabolic homeostasis. It has long been recognized that endothelial dysfunction participates in the pathogenesis of atherosclerosis from early, preclinical lesions to advanced, thrombotic complications. In addition, endothelial dysfunction has been recently implicated in the development of insulin resistance and type 2 diabetes mellitus (T2DM). Considering that states of insulin resistance (eg, metabolic syndrome, impaired fasting glucose, impaired glucose tolerance, and T2DM) represent the most prevalent metabolic disorders and risk factors for atherosclerosis, it is of considerable scientific and clinical interest that both metabolic and vascular disorders have endothelial dysfunction as a common background. Importantly, endothelial dysfunction has been associated with adverse outcomes in patients with established cardiovascular disease, and a growing body of evidence indicates that endothelial dysfunction also imparts adverse prognosis in states of insulin resistance. In this review, we discuss the association of insulin resistance and T2DM with endothelial dysfunction and vascular disease, with a focus on the underlying mechanisms and prognostic implications of the endothelial dysfunction in metabolic and vascular disorders. We also address current therapeutic strategies for the improvement of endothelial dysfunction.

  6. Nanomedicine approaches in vascular disease: a review.

    Science.gov (United States)

    Gupta, Anirban Sen

    2011-12-01

    Nanomedicine approaches have revolutionized the treatment of cancer and vascular diseases, where the limitations of rapid nonspecific clearance, poor biodistribution and harmful side effects associated with direct systemic drug administration can be overcome by packaging the agents within sterically stabilized, long-circulating nanovehicles that can be further surface-modified with ligands to actively target cellular/molecular components of the disease. With significant advancements in genetics, proteomics, cellular and molecular biology and biomaterials engineering, the nanomedicine strategies have become progressively refined regarding the modulation of surface and bulk chemistry of the nanovehicles, control of drug release kinetics, manipulation of nanoconstruct geometry and integration of multiple functionalities on single nanoplatforms. The current review aims to capture the various nanomedicine approaches directed specifically toward vascular diseases during the past two decades. Analysis of the promises and limitations of these approaches will help identify and optimize vascular nanomedicine systems to enhance their efficacy and clinical translation in the future. Nanomedicine-based approaches have had a major impact on the treatment and diagnosis of malignancies and vascular diseases. This review discusses various nanomedicine approaches directed specifically toward vascular diseases during the past two decades, highlighting their advantages, limitations and offering new perspectives on future applications. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Linear network error correction coding

    CERN Document Server

    Guang, Xuan

    2014-01-01

    There are two main approaches in the theory of network error correction coding. In this SpringerBrief, the authors summarize some of the most important contributions following the classic approach, which represents messages by sequences?similar to algebraic coding,?and also briefly discuss the main results following the?other approach,?that uses the theory of rank metric codes for network error correction of representing messages by subspaces. This book starts by establishing the basic linear network error correction (LNEC) model and then characterizes two equivalent descriptions. Distances an

  8. Malfunctions in radioactivity sensors' networks

    Science.gov (United States)

    Khalipova, Veronika; Damart, Guillaume; Beauzamy, Bernard; Bruna, Giovanni

    2018-01-01

    The capacity to promptly and efficiently detect any source of contamination of the environment (a radioactive cloud) at a local and a country scale is mandatory to a safe and secure exploitation of civil nuclear energy. It must rely upon a robust network of measurement devices, to be optimized vs. several parameters, including the overall reliability, the investment, the operation and maintenance costs. We show that a network can be arranged in different ways, but many of them are inadequate. Through simulations, we test the efficiency of several configurations of sensors, in the same domain. The denser arrangement turns out to be the more efficient, but the efficiency is increased when sensors are non-uniformly distributed over the country, with accumulation at the borders. In the case of France, as radioactive threats are most likely to come from the East, the best solution is densifying the sensors close to the eastern border. Our approach differs from previous work because it is "failure oriented": we determine the laws of probability for all types of failures and deduce in this respect the best organization of the network.

  9. Malfunctions in radioactivity sensors' networks

    Directory of Open Access Journals (Sweden)

    Khalipova Veronika

    2018-01-01

    Full Text Available The capacity to promptly and efficiently detect any source of contamination of the environment (a radioactive cloud at a local and a country scale is mandatory to a safe and secure exploitation of civil nuclear energy. It must rely upon a robust network of measurement devices, to be optimized vs. several parameters, including the overall reliability, the investment, the operation and maintenance costs. We show that a network can be arranged in different ways, but many of them are inadequate. Through simulations, we test the efficiency of several configurations of sensors, in the same domain. The denser arrangement turns out to be the more efficient, but the efficiency is increased when sensors are non-uniformly distributed over the country, with accumulation at the borders. In the case of France, as radioactive threats are most likely to come from the East, the best solution is densifying the sensors close to the eastern border. Our approach differs from previous work because it is "failure oriented": we determine the laws of probability for all types of failures and deduce in this respect the best organization of the network.

  10. Persistent fifth arch anomalies - broadening the spectrum to include a variation of double aortic arch vascular ring

    Energy Technology Data Exchange (ETDEWEB)

    Newman, Beverley; Chan, Frandics [Stanford Children' s Hospital and Stanford University, Department of Radiology, Stanford, CA (United States); Hanneman, Kate [University of Toronto, Department of Medical Imaging, Toronto, ON (Canada)

    2016-12-15

    Fifth arch anomalies are rare and complex and frequently misdiagnosed or mistaken for other entities. We report a double arch vascular ring that is thought to consist of right fourth arch and left fifth arch components, a previously undescribed persistent fifth arch variant. The currently recognized spectrum and classification of fifth arch vascular anomalies are expanded along with illustrative images to justify the proposed changes. Reviewing and expanding the classification of fifth arch anomalies to include a double arch ring variant will promote recognition, correct diagnosis and appropriate management of these anomalies. (orig.)

  11. The vascular pattern in the flower of some Mesembryanthemaceae: Aptenia cordifolia and Dorotheanthus bellidiformis. The effect of an ontogenetical shifting on the vascular pattern and vascular conservatism

    NARCIS (Netherlands)

    Meulen-Bruijns, van der C.

    1976-01-01

    1. The vascular pattern in the flower at various stages of maturity of Aptenia cordifolia and Dorotheanthus bellidiformis is examined. 2. The vascular pattern of Dorotheanthus has been compared with that of Aptenia: typologically, Dorotheanthus is derived from Aptenia. 3. The vascular pattern of

  12. Vascular training and endovascular practice in Europe

    DEFF Research Database (Denmark)

    Liapis, C.D.; Avgerinos, E.D.; Sillesen, H.

    2009-01-01

    specialties was distributed to a VS educator within 14 European countries. European Vascular and Endovascular Monitor (EVEM) data also were processed to correlate endovascular practice with training models. RESULTS: Fourteen questionnaires were gathered. Vascular training in Europe appears in 3 models: 1....... Mono-specialty (independence): 7 countries, 2. Subspecialty: 5 countries, 3. An existing specialty within general surgery: 2 countries. Independent compared to non-independent certification shortens overall training length (5.9 vs 7.9 years, p=0.006), while increasing overall training devoted......% respectively. Countries with independent vascular certification, despite their lower average endovascular index (procedures per 100,000 population), reported a higher growth rate of aortic endovascular procedures (VS independent 132% vs VS non-independent 87%), within a four-year period (2003-2007). Peripheral...

  13. Intraoperative digital angiography: Peripheral vascular applications

    International Nuclear Information System (INIS)

    Bell, K.; Reifsteck, J.E.; Binet, E.F.; Fleisher, H.J.

    1986-01-01

    Intraoperative digital angiography is the procedure of choice for the peripheral vascular surgeon who wishes to evaluate his results before terminating anesthesia. Two operating suites at the John L. McClellan Memorial Veterans Hospital are equipped with permanent ceiling-mounted Philips C-arm fluoroscopes and share an ADAC 4100 digital angiographic system. In the last 18 months, 40 peripheral vascular intraoperative digital angiographic procedures have been performed, in all but two cases using direct arterial puncture. In 65% of cases, the intraoperative study showed no significant abnormality. In 12.5%, minor abnormalities not requiring reoperation were seen. In 22.5% of cases, the intraoperative digital angiogram revealed a significant abnormality requiring immediate operative revision. None of the patients who underwent reoperation experienced postoperative sequelae. Intraoperative digital angiography is useful in identifying complications of peripheral vascular operations

  14. Viral haemorrhagic fever and vascular alterations.

    Science.gov (United States)

    Aleksandrowicz, P; Wolf, K; Falzarano, D; Feldmann, H; Seebach, J; Schnittler, H

    2008-02-01

    Pathogenesis of viral haemorrhagic fever (VHF) is closely associated with alterations of the vascular system. Among the virus families causing VHF, filoviruses (Marburg and Ebola) are the most fatal, and will be focused on here. After entering the body, Ebola primarily targets monocytes/macrophages and dendritic cells. Infected dendritic cells are largely impaired in their activation potency, likely contributing to the immune suppression that occurs during filovirus infection. Monocytes/macrophages, however, immediately activate after viral contact and release reasonable amounts of cytokines that target the vascular system, particularly the endothelial cells. Some underlying molecular mechanisms such as alteration of the vascular endothelial cadherin/catenin complex, tyrosine phosphorylation, expression of cell adhesion molecules, tissue factor and the effect of soluble viral proteins released from infected cells to the blood stream will be discussed.

  15. Automatic computation of radiative corrections

    International Nuclear Information System (INIS)

    Fujimoto, J.; Ishikawa, T.; Shimizu, Y.; Kato, K.; Nakazawa, N.; Kaneko, T.

    1997-01-01

    Automated systems are reviewed focusing on their general structure and requirement specific to the calculation of radiative corrections. Detailed description of the system and its performance is presented taking GRACE as a concrete example. (author)

  16. Publisher Correction: On our bookshelf

    Science.gov (United States)

    Karouzos, Marios

    2018-03-01

    In the version of this Books and Arts originally published, the book title Spectroscopy for Amateur Astronomy was incorrect; it should have read Spectroscopy for Amateur Astronomers. This has now been corrected.

  17. Self-correcting quantum computers

    International Nuclear Information System (INIS)

    Bombin, H; Chhajlany, R W; Horodecki, M; Martin-Delgado, M A

    2013-01-01

    Is the notion of a quantum computer (QC) resilient to thermal noise unphysical? We address this question from a constructive perspective and show that local quantum Hamiltonian models provide self-correcting QCs. To this end, we first give a sufficient condition on the connectedness of excitations for a stabilizer code model to be a self-correcting quantum memory. We then study the two main examples of topological stabilizer codes in arbitrary dimensions and establish their self-correcting capabilities. Also, we address the transversality properties of topological color codes, showing that six-dimensional color codes provide a self-correcting model that allows the transversal and local implementation of a universal set of operations in seven spatial dimensions. Finally, we give a procedure for initializing such quantum memories at finite temperature. (paper)

  18. Correcting AUC for Measurement Error.

    Science.gov (United States)

    Rosner, Bernard; Tworoger, Shelley; Qiu, Weiliang

    2015-12-01

    Diagnostic biomarkers are used frequently in epidemiologic and clinical work. The ability of a diagnostic biomarker to discriminate between subjects who develop disease (cases) and subjects who do not (controls) is often measured by the area under the receiver operating characteristic curve (AUC). The diagnostic biomarkers are usually measured with error. Ignoring measurement error can cause biased estimation of AUC, which results in misleading interpretation of the efficacy of a diagnostic biomarker. Several methods have been proposed to correct AUC for measurement error, most of which required the normality assumption for the distributions of diagnostic biomarkers. In this article, we propose a new method to correct AUC for measurement error and derive approximate confidence limits for the corrected AUC. The proposed method does not require the normality assumption. Both real data analyses and simulation studies show good performance of the proposed measurement error correction method.

  19. Libertarian Anarchism Is Apodictically Correct

    OpenAIRE

    Redford, James

    2011-01-01

    James Redford, "Libertarian Anarchism Is Apodictically Correct", Social Science Research Network (SSRN), Dec. 15, 2011, 9 pp., doi:10.2139/ssrn.1972733. ABSTRACT: It is shown that libertarian anarchism (i.e., consistent liberalism) is unavoidably true.

  20. Vacuum assisted closure in vascular surgery.

    Science.gov (United States)

    Beno, M; Martin, J; Sager, P

    2011-01-01

    Vacuum assisted closure (VAC-therapy) is a well established method in nearly all surgical disciplines. The aim is to present the efficiency of vacuum assisted closure in the treatment of acute and chronic wounds in patients admitted in the department of vascular surgery. Within the year 2008 there were 59 patients (44 men, 15 women) treated with VAC therapy in our Department of Vascular surgery (Landshut, Germany). VAC was used 22x (37.28 %) in therapy of ulcus cruris (venous, arterial, mixed genesis), 15x (25.42%) in patients with diabetic foot syndrome, 12x (20.33%) in secondary healing wounds and infected wounds, 5x (8.47%) in wounds after several injuries and soft skin tissue infections and 5x (8.47%) in wound infections connected with vascular graft infections after vascular revascularization. VAC therapy seems to be very effective in the management of patients with venous ulcers, especially after a proper surgical treatment (100%), patients with soft skin tissue infections (100%) and secondary healing wounds (100%) especially in combination with MESH-Grafting. In patients with diabetic foot syndrome (80%) and peripheral arterial occlusive disease (72.7%), an evaluation of peripheral blood perfusion and revascularization prior to VAC therapy is often necessary. Although VAC was used 5x in the therapy of infected vascular grafts, successful preservation of infected graft material was observed in only one case (infection of PTFE femoro-popliteal bypass graft). Vacuum assisted closure in vascular surgery proved to be simple and efficient method in therapy of acute and chronic wounds. The efficiency of VAC systems in therapy of infected graft material after revascularization needs further studies (Tab. 3, Ref. 10).

  1. The pathology and pathophysiology of vascular dementia.

    Science.gov (United States)

    Kalaria, Raj N

    2017-12-19

    Vascular dementia (VaD) is widely recognised as the second most common type of dementia. Consensus and accurate diagnosis of clinically suspected VaD relies on wide-ranging clinical, neuropsychological and neuroimaging measures in life but more importantly pathological confirmation. Factors defining subtypes of VaD include the nature and extent of vascular pathologies, degree of involvement of extra and intracranial vessels and the anatomical location of tissue changes as well as time after the initial vascular event. Atherosclerotic and cardioembolic diseases combined appear the most common subtypes of vascular brain injury. In recent years, cerebral small vessel disease (SVD) has gained prominence worldwide as an important substrate of cognitive impairment. SVD is characterised by arteriolosclerosis, lacunar infarcts and cortical and subcortical microinfarcts and diffuse white matter changes, which involve myelin loss and axonal abnormalities. Global brain atrophy and focal degeneration of the cerebrum including medial temporal lobe atrophy are also features of VaD similar to Alzheimer's disease. Hereditary arteriopathies have provided insights into the mechanisms of dementia particularly how arteriolosclerosis, a major contributor of SVD promotes cognitive impairment. Recently developed and validated neuropathology guidelines indicated that the best predictors of vascular cognitive impairment were small or lacunar infarcts, microinfarcts, perivascular space dilation, myelin loss, arteriolosclerosis and leptomeningeal cerebral amyloid angiopathy. While these substrates do not suggest high specificity, VaD is likely defined by key neuronal and dendro-synaptic changes resulting in executive dysfunction and related cognitive deficits. Greater understanding of the molecular pathology is needed to clearly define microvascular disease and vascular substrates of dementia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Error correcting coding for OTN

    DEFF Research Database (Denmark)

    Justesen, Jørn; Larsen, Knud J.; Pedersen, Lars A.

    2010-01-01

    Forward error correction codes for 100 Gb/s optical transmission are currently receiving much attention from transport network operators and technology providers. We discuss the performance of hard decision decoding using product type codes that cover a single OTN frame or a small number...... of such frames. In particular we argue that a three-error correcting BCH is the best choice for the component code in such systems....

  3. Spelling Correction in User Interfaces.

    Science.gov (United States)

    1982-12-20

    conventional typescript -oriented command language, where most com- mands consist of a verb followed by a sequence of arguments. Most user terminals are...and explanations. not part of the typescripts . 2 SPFE.LING CORRLC1iON IN USR IN"RFAC’S 2. Design Issues We were prompted to look for a new correction...remaining 73% led us to wonder what other mechanisms might permit further corrections while retaining the typescript -style interface. Most of the other

  4. Perioperative smoking cessation in vascular surgery

    DEFF Research Database (Denmark)

    Kehlet, M.; Heesemann, Sabine; Tonnesen, H.

    2015-01-01

    Background: The effect of intensive smoking cessation programs on postoperative complications has never before been assessed in soft tissue surgery when smoking cessation is initiated on the day of surgery. Methods: A single-blinded randomized clinical trial conducted at two vascular surgery...... departments in Denmark. The intervention group was offered the Gold Standard Program (GSP) for smoking cessation intervention. The control group was offered the departments' standard care. Inclusion criteria were patients with planned open peripheral vascular surgery and who were daily smokers. According...

  5. Genealogy of training in vascular neurosurgery.

    Science.gov (United States)

    Chowdhry, Shakeel A; Spetzler, Robert F

    2014-02-01

    Remarkable advances and changes in the landscape of neurovascular disease have occurred recently. Concurrently, a paradigm shift in training and resident education is underway. This crossroad of unique opportunities and pressures necessitates creative change in the training of future vascular neurosurgeons to allow incorporation of surgical advances, new technology, and supplementary treatment modalities in a setting of reduced work hours and increased public scrutiny. This article discusses the changing landscape in neurovascular disease treatment, followed by the recent changes in resident training, and concludes with our view of the future of training in vascular neurosurgery.

  6. Vascularized Composite Allografts: Procurement, Allocation, and Implementation.

    Science.gov (United States)

    Rahmel, Axel

    Vascularized composite allotransplantation is a continuously evolving area of modern transplant medicine. Recently, vascularized composite allografts (VCAs) have been formally classified as 'organs'. In this review, key aspects of VCA procurement are discussed, with a special focus on interaction with the procurement of classical solid organs. In addition, options for a matching and allocation system that ensures VCA donor organs are allocated to the best-suited recipients are looked at. Finally, the different steps needed to promote VCA transplantation in society in general and in the medical community in particular are highlighted.

  7. Early vascular plants in the Czech Republic

    OpenAIRE

    Uhlířová, Monika

    2017-01-01

    Vascular plants are characterized as a group of plants, which are already fully adapted to live on the land. Their evolution is a result of a set of adaptations that have required the necessary changes at anatomical and morphological level. Some evidences about the rise of vascular plants appear in the fossil record from the Middle Ordovician in the form of spores and later also from the Early Silurian in the form of megafossils. The aim of the thesis is to briefly describe and discuss the mo...

  8. Radiological study of cerebro-vascular accidents

    International Nuclear Information System (INIS)

    Misri, H.T.; Kabawe, Bassam

    1991-01-01

    The role of computerized tomography scanner in studying the cerebro-vascular accidents has been discussed. One hundred fifty patients with cerebro-vascular accidents were studied at Aleppo University Hospital between 1989-1990. Clinical history and physical examination were recorded, as well as, computerized tomography scanning in all cases without using the contrast media mostly. Relationship between the density of the lesion (inforctionor hemorrhage) and the time has been found. This relationship can help in forensic medicine. (author). 29 refs., 5 tabs., 2 figs

  9. Angiogenesis and vascular targeting: Relevance for hyperthermia

    DEFF Research Database (Denmark)

    Horsman, Michael R

    2008-01-01

    The creation of a functional blood supply from the normal tissue vasculature via the process of angiogenesis is critical for the continued growth and development of solid tumours. This importance has led to the concept of targeting the tumour vasculature as a therapeutic strategy, and two major...... types of vascular targeting agents (VTAs) have developed; those that inhibit the angiogenic process-angiogenesis inhibiting agents (AIAs)-and those that specifically damage the already established neovasculature-vascular disrupting agents (VDAs). The tumour vasculature also plays a critical role...

  10. Age related changes in tumor vascularity

    International Nuclear Information System (INIS)

    Loerelius, L.E.; Stridbeck, H.

    1984-01-01

    VX 2 tumors in the rabbit hind leg were investigated at one, two and three weeks of age. Angiograms were compared with vascular casts. The tumors grew rapidly the first two weeks of age. Large variations in vascularity were noted between tumors of different ages. With increasing age arteriovenous shunts at the tumor periphery and areas of avascularity of necrosis in the tumor center increased in size. Possible reasons for tumor necrosis are increased tissue pressure, anoxia caused by arteriovenous shunts and elevation in venous pressure. The natural history of the VX 2 tumor must be considered in every experimental study of the effect of any treatment. (orig.)

  11. Quantum error correction for beginners

    International Nuclear Information System (INIS)

    Devitt, Simon J; Nemoto, Kae; Munro, William J

    2013-01-01

    Quantum error correction (QEC) and fault-tolerant quantum computation represent one of the most vital theoretical aspects of quantum information processing. It was well known from the early developments of this exciting field that the fragility of coherent quantum systems would be a catastrophic obstacle to the development of large-scale quantum computers. The introduction of quantum error correction in 1995 showed that active techniques could be employed to mitigate this fatal problem. However, quantum error correction and fault-tolerant computation is now a much larger field and many new codes, techniques, and methodologies have been developed to implement error correction for large-scale quantum algorithms. In response, we have attempted to summarize the basic aspects of quantum error correction and fault-tolerance, not as a detailed guide, but rather as a basic introduction. The development in this area has been so pronounced that many in the field of quantum information, specifically researchers who are new to quantum information or people focused on the many other important issues in quantum computation, have found it difficult to keep up with the general formalisms and methodologies employed in this area. Rather than introducing these concepts from a rigorous mathematical and computer science framework, we instead examine error correction and fault-tolerance largely through detailed examples, which are more relevant to experimentalists today and in the near future. (review article)

  12. Endovascular repair of abdominal aortic aneurysms: vascular anatomy, device selection, procedure, and procedure-specific complications.

    Science.gov (United States)

    Bryce, Yolanda; Rogoff, Philip; Romanelli, Donald; Reichle, Ralph

    2015-01-01

    Abdominal aortic aneurysm (AAA) is abnormal dilatation of the aorta, carrying a substantial risk of rupture and thereby marked risk of death. Open repair of AAA involves lengthy surgery time, anesthesia, and substantial recovery time. Endovascular aneurysm repair (EVAR) provides a safer option for patients with advanced age and pulmonary, cardiac, and renal dysfunction. Successful endovascular repair of AAA depends on correct selection of patients (on the basis of their vascular anatomy), choice of the correct endoprosthesis, and familiarity with the technique and procedure-specific complications. The type of aneurysm is defined by its location with respect to the renal arteries, whether it is a true or false aneurysm, and whether the common iliac arteries are involved. Vascular anatomy can be divided more technically into aortic neck, aortic aneurysm, pelvic perfusion, and iliac morphology, with grades of difficulty with respect to EVAR, aortic neck morphology being the most common factor to affect EVAR appropriateness. When choosing among the devices available on the market, one must consider the patient's vascular anatomy and choose between devices that provide suprarenal fixation versus those that provide infrarenal fixation. A successful technique can be divided into preprocedural imaging, ancillary procedures before AAA stent-graft placement, the procedure itself, postprocedural medical therapy, and postprocedural imaging surveillance. Imaging surveillance is important in assessing complications such as limb thrombosis, endoleaks, graft migration, enlargement of the aneurysm sac, and rupture. Last, one must consider the issue of radiation safety with regard to EVAR. (©)RSNA, 2015.

  13. Engineering the mechanical and biological properties of nanofibrous vascular grafts for in situ vascular tissue engineering.

    Science.gov (United States)

    Henry, Jeffrey J D; Yu, Jian; Wang, Aijun; Lee, Randall; Fang, Jun; Li, Song

    2017-08-17

    Synthetic small diameter vascular grafts have a high failure rate, and endothelialization is critical for preventing thrombosis and graft occlusion. A promising approach is in situ tissue engineering, whereby an acellular scaffold is implanted and provides stimulatory cues to guide the in situ remodeling into a functional blood vessel. An ideal scaffold should have sufficient binding sites for biomolecule immobilization and a mechanical property similar to native tissue. Here we developed a novel method to blend low molecular weight (LMW) elastic polymer during electrospinning process to increase conjugation sites and to improve the mechanical property of vascular grafts. LMW elastic polymer improved the elasticity of the scaffolds, and significantly increased the amount of heparin conjugated to the micro/nanofibrous scaffolds, which in turn increased the loading capacity of vascular endothelial growth factor (VEGF) and prolonged the release of VEGF. Vascular grafts were implanted into the carotid artery of rats to evaluate the in vivo performance. VEGF treatment significantly enhanced endothelium formation and the overall patency of vascular grafts. Heparin coating also increased cell infiltration into the electrospun grafts, thus increasing the production of collagen and elastin within the graft wall. This work demonstrates that LMW elastic polymer blending is an approach to engineer the mechanical and biological property of micro/nanofibrous vascular grafts for in situ vascular tissue engineering.

  14. Vascular Structure Identification in Intraoperative 3D Contrast-Enhanced Ultrasound Data

    Directory of Open Access Journals (Sweden)

    Elisee Ilunga-Mbuyamba

    2016-04-01

    Full Text Available In this paper, a method of vascular structure identification in intraoperative 3D Contrast-Enhanced Ultrasound (CEUS data is presented. Ultrasound imaging is commonly used in brain tumor surgery to investigate in real time the current status of cerebral structures. The use of an ultrasound contrast agent enables to highlight tumor tissue, but also surrounding blood vessels. However, these structures can be used as landmarks to estimate and correct the brain shift. This work proposes an alternative method for extracting small vascular segments close to the tumor as landmark. The patient image dataset involved in brain tumor operations includes preoperative contrast T1MR (cT1MR data and 3D intraoperative contrast enhanced ultrasound data acquired before (3D-iCEUS s t a r t and after (3D-iCEUS e n d tumor resection. Based on rigid registration techniques, a preselected vascular segment in cT1MR is searched in 3D-iCEUS s t a r t and 3D-iCEUS e n d data. The method was validated by using three similarity measures (Normalized Gradient Field, Normalized Mutual Information and Normalized Cross Correlation. Tests were performed on data obtained from ten patients overcoming a brain tumor operation and it succeeded in nine cases. Despite the small size of the vascular structures, the artifacts in the ultrasound images and the brain tissue deformations, blood vessels were successfully identified.

  15. Computer tomography valorization of the vascular lingual channels in the jaw

    International Nuclear Information System (INIS)

    Costantino, Sebastian; Capiel, Carlos h; Bouzas, Carlos; Vuotto, Miguel; Ferrari, Daniela; Bazzano, Sebastian

    2006-01-01

    Purpose: To determine the frequency, location and position of vascular lingual channels of jaw by dental CT and classifying them based on its location. Material and methods: Dental CT of 100 consecutive patients were reevaluated as previous evaluation to the positioning of dental implants. They are classified by linking their location on the jaw with the number of tooth present or absent in that area. Results: All patients had at least one lingual vascular channel in the jaw; 36 patients presented two channels, eight patients presented three and a patient presented four. The more frequent location was between the sectors of the pieces 31 and 41. Sixteen patients showed two channels (superior and inferior) in that location. The second location by frequency was between pieces 32 and 33 (nine patients). The average distance between the lingual surface of the alveolar rim and the vascular channels was of 16 mm. Conclusion: the dental CT is an excellent method for the identification of the vascular lingual channels by its multiplanar capacity and appropriate image resolution. The characterization and classification of these conduits by a method of easy reading for the radiologists and the dentists assure a correct pre surgical valuation avoiding hemorrhages during the jaw perforation in the positioning of dental implants. (author) [es

  16. Vascular plugs - A key companion to Interventionists - 'Just Plug it'.

    Science.gov (United States)

    Ramakrishnan, Sivasubramanian

    2015-01-01

    Vascular plugs are ideally suited to close extra-cardiac, high flowing vascular communications. The family of vascular plugs has expanded. Vascular plugs in general have a lower profile and the newer variants can be delivered even through a diagnostic catheter. These features make them versatile and easy to use. The Amplatzer vascular plugs are also used for closing intracardiac defects including coronary arterio-venous fistula and paravalvular leakage in an off-label fashion. In this review, the features of currently available vascular plugs are reviewed along with tips and tricks of using them in the cardiac catheterization laboratory. Copyright © 2015. Published by Elsevier B.V.

  17. Oscillation of Angiogenesis and Vascular Dropout in Progressive Human Vascular Disease. [Vascular Pattern as Useful Read-Out of Complex Molecular Signaling

    Science.gov (United States)

    Parsons-Wingerter, Patricia

    2010-01-01

    When analyzed by VESsel GENeration Analysis (VESGEN) software, vascular patterns provide useful integrative read-outs of complex, interacting molecular signaling pathways. Using VESGEN, we recently discovered and published our innovative, surprising findings that angiogenesis oscillated with vascular dropout throughout progression of diabetic retinopathy, a blinding vascular disease. Our findings provide a potential paradigm shift in the current prevailing view on progression and treatment of this disease, and a new early-stage window of regenerative therapeutic opportunities. The findings also suggest that angiogenesis may oscillate with vascular disease in a homeostatic-like manner during early stages of other inflammatory progressive diseases such as cancer and coronary vascular disease.

  18. Basic Components of Vascular Connective Tissue and Extracellular Matrix.

    Science.gov (United States)

    Halper, Jaroslava

    2018-01-01

    Though the composition of the three layers constituting the blood vessel wall varies among the different types of blood vessels, and some layers may even be missing in capillaries, certain basic components, and properties are shared by all blood vessels, though each histologically distinct layer contains a unique complement of extracellular components, growth factors and cytokines, and cell types as well. The structure and composition of vessel layers informs and is informed by the function of the particular blood vessel. The adaptation of the composition and the resulting function of the extracellular matrix (ECM) to changes in circulation/blood flow and a variety of other extravascular stimuli can be characterized as remodeling spearheaded by vascular cells. There is a surprising amount of cell traffic among the three layers. It starts with endothelial cell mediated transmigration of inflammatory cells from the bloodstream into the subendothelium, and then into tissue adjoining the blood vessel. Smooth muscle cells and a variety of adventitial cells reside in tunica media and tunica externa, respectively. The latter cells are a mixture of progenitor/stem cells, fibroblasts, myofibroblasts, pericytes, macrophages, and dendritic cells and respond to endothelial injury by transdifferentiation as they travel into the two inner layers, intima and media for corrective mission in the ECM composition. This chapter addresses the role of various vascular cell types and ECM components synthesized by them in maintenance of normal structure and in their contribution to major pathological processes, such as atherosclerosis, organ fibrosis, and diabetic retinopathy. © 2018 Elsevier Inc. All rights reserved.

  19. CENTRAL VENOUS CATHETER AS A VASCULAR APPROACH TO HEMODIALYSTS

    Directory of Open Access Journals (Sweden)

    Verica Djordjevic

    2001-03-01

    Full Text Available The application of the central venous catheter (CVC as a temporary orpermanent vascular approach to hemodialysis has been practiced in our Center since1994. So far 30 (12,6% patients have been thus treated. The primary application hasbeen done in 25 patients, namely: the first making of the A V fistula has been done in16, the ABT in 6, while the vascular approach correction in 3 patients. The secondaryapplication has been done in 5 patients. The infection episode incidence concerningthe CVC application is 20 infections per 1.000 patients. This is the upper limitaccording to the data given in the literature (5, rang 3-20. The average duration of thecatheter is 21 + - 13 days (rang 1-47. Two-volume catheters have been used for ajugular approach though less often for a femoral one. The unsuccessful placing due tothe catheter thrombosis has occurred in 4 patients, the catheter drop-out and itsreplacing have been done in 2 patients, while no replacement has happened in onečaše. The treatment has been stopped in one patient. Tn four patients the cerebrovascularinsult has happened after placing the CVC. The mortality rate is 26,6%,that is, K patients, namely: 4 due to cerebrovascular insult, one due to lung emboly,one due to heart weakness and one due to the sepsis from the V fistula. One patientdied at home for unknown reason. A high infection episode incidence rate is related toinadequate patients' placing so that their location in the rooms for intensive care is away of reducing it. It is necessary to provide for general aseptic procedure at work aswell as for betterment of the accompanying procedures (hemoculture, antibiograms,sterilization in order to maintain a safe catheter function.

  20. Results from the Australasian Vascular Surgical Audit: the inaugural year.

    Science.gov (United States)

    Beiles, C Barry; Bourke, Bernie; Thomson, Ian

    2012-03-01

    The Australian and New Zealand Society for Vascular Surgery has incorporated a constitutional change to administer a self-funded compulsory vascular surgery audit since January 2010. This is a bi-national quality assurance activity that captures all procedures performed in both countries. Data is collected at two points in the clinical admission; at operation and at discharge and data entry is via the Internet. Security is stringent and confidentiality is guaranteed by Commonwealth privilege. Data privacy is maximized by encryption. The application is flexible and administered by a dedicated administrator with a help-desk facility. Reports are available to provide real-time feedback of user performance compared with the peer group data in key categories of arterial surgery. A structured hierarchy for data management has been established to assess four main categories of performance: mortality after aortic surgery, stroke and death after carotid surgery, patency and limb salvage after infrainguinal bypass and patency after arteriovenous access for haemodialysis. Data is analysed using risk-adjustment techniques and an algorithm for management of underperformance has been followed. Data validation has been performed. The outcomes in all categories have been of a high standard and correction of erroneous data in a single statistical outlier has negated underperformance. The audit has captured only 65% of the estimated procedures in Australia in the first year, but data quality is good. The feasibility of a complete compulsory bi-national audit has now been established and will be the benchmark for other craft groups in the current environment of accountability. © 2012 The Authors. ANZ Journal of Surgery © 2012 Royal Australasian College of Surgeons.

  1. Dual modal ultra-bright nanodots with aggregation-induced emission and gadolinium-chelation for vascular integrity and leakage detection.

    Science.gov (United States)

    Feng, Guangxue; Li, Jackson Liang Yao; Claser, Carla; Balachander, Akhila; Tan, Yingrou; Goh, Chi Ching; Kwok, Immanuel Weng Han; Rénia, Laurent; Tang, Ben Zhong; Ng, Lai Guan; Liu, Bin

    2018-01-01

    The study of blood brain barrier (BBB) functions is important for neurological disorder research. However, the lack of suitable tools and methods has hampered the progress of this field. Herein, we present a hybrid nanodot strategy, termed AIE-Gd dots, comprising of a fluorogen with aggregation-induced emission (AIE) characteristics as the core to provide bright and stable fluorescence for optical imaging, and gadolinium (Gd) for accurate quantification of vascular leakage via inductively-coupled plasma mass spectrometry (ICP-MS). In this report, we demonstrate that AIE-Gd dots enable direct visualization of brain vascular networks under resting condition, and that they form localized punctate aggregates and accumulate in the brain tissue during experimental cerebral malaria, indicative of hemorrhage and BBB malfunction. With its superior detection sensitivity and multimodality, we hereby propose that AIE-Gd dots can serve as a better alternative to Evans blue for visualization and quantification of changes in brain barrier functions. Copyright © 2017. Published by Elsevier Ltd.

  2. MDCT assessment of tracheomalacia in symptomatic infants with mediastinal aortic vascular anomalies: preliminary technical experience

    International Nuclear Information System (INIS)

    Lee, Edward Y.; Mason, Keira P.; Zurakowski, David; Waltz, David A.; Ralph, Amy; Riaz, Farhana; Boiselle, Phillip M.

    2008-01-01

    Mediastinal aortic vascular anomalies are relatively common causes of extrinsic central airway narrowing in infants with respiratory symptoms. Surgical correction of mediastinal aortic vascular anomalies alone might not adequately treat airway symptoms if extrinsic narrowing is accompanied by intrinsic tracheomalacia (TM), a condition that escapes detection on routine end-inspiratory imaging. Paired inspiratory-expiratory multidetector CT (MDCT) has the potential to facilitate early diagnosis and timely management of TM in symptomatic infants with mediastinal aortic vascular anomalies. To assess the technical feasibility of paired inspiratory-expiratory MDCT for evaluating TM among symptomatic infants with mediastinal aortic vascular anomalies. The study group consisted of five consecutive symptomatic infants (four male, one female; mean age 4.1 months, age range 2 weeks to 6 months) with mediastinal aortic vascular anomalies who were referred for paired inspiratory-expiratory MDCT during a 22-month period. CT angiography was concurrently performed during the end-inspiration phase of the study. Two pediatric radiologists in consensus reviewed all CT images in a randomized and blinded fashion. The end-inspiration and end-expiration CT images were reviewed for the presence and severity of tracheal narrowing. TM was defined as ≥50% reduction in tracheal cross-sectional luminal area between end-inspiration and end-expiration. The presence of TM was compared to the bronchoscopy results when available (n = 4). Paired inspiratory-expiratory MDCT was technically successful in all five patients. Mediastinal aortic vascular anomalies included a right aortic arch with an aberrant left subclavian artery (n = 2), innominate artery compression (n = 2), and a left aortic arch with an aberrant right subclavian artery (n 1). Three (60%) of the five patients demonstrated focal TM at the level of mediastinal aortic vascular anomalies. The CT results were concordant with the results

  3. Vascular risk factors, cognitve decline, and dementia

    Directory of Open Access Journals (Sweden)

    E Duron

    2008-04-01

    Full Text Available E Duron, Olivier HanonBroca Hospital, Paris, FranceAbstract: Dementia is one of the most important neurological disorders in the elderly. Aging is associated with a large increase in the prevalence and incidence of degenerative (Alzheimer’s disease and vascular dementia, leading to a devastating loss of autonomy. In view of the increasing longevity of populations worldwide, prevention of dementia has turned into a major public health challenge. In the past decade, several vascular risk factors have been found to be associated with vascular dementia but also Alzheimer’s disease. Some longitudinal studies, have found significant associations between hypertension, diabetus mellitus, and metabolic syndrome, assessed at middle age, and dementia. Studies assessing the link between hypercholesterolemia, atrial fibrillation, smoking, and dementia have given more conflicting results. Furthermore, some studies have highlighted the possible protective effect of antihypertensive therapy on cognition and some trials are evaluating the effects of statins and treatments for insulin resistance. Vascular risk factors and their treatments are a promising avenue of research for prevention of dementia, and further long-term, placebo-controlled, randomized studies, need to be performed.Keywords: dementia, hypertension, diabetus mellitus, hypercholesterolemia, metabolic syndrome

  4. Vascular anatomy in angiography for magnetic resonance

    International Nuclear Information System (INIS)

    Charry Lopez, Marco Luciano; Rivera Gomez, Juan Enrique

    1998-01-01

    A review of basic anatomical concepts and main variants, as well as some anatomical anomalies of the central nervous system vascularity, these concepts are considered essential for the interpretation of magnetic resonance angiography with time-of-flight (TOF) and phase-contrast (PC) methods

  5. CT imaging of cervical spinal vascular malformation

    International Nuclear Information System (INIS)

    Ueda, Takashi; Iwamoto, Munehisa; Miyamoto, Etsuo; Kuriyama, Tsuyoshi; Hayama, Tsuneto

    1982-01-01

    The patient had a history of the onset of motor paralysis of the right upper and lower extremities. Eight years later, numbness of the right upper extremity and a severe neck pain developed, and transverse paralysis of the lower extremities appeared in about 10 hours. CT demonstrated the presence of spinal vascular abnormality. Angiography suggested arteriovenous malformation of glomus type. (Chiba, N.)

  6. NEURO-VASCULAR INJURIES ASSOCIATED WITH LIMB ...

    African Journals Online (AJOL)

    hi-tech

    2000-12-01

    Dec 1, 2000 ... Subjects: Forty three patients with bone fractures associated with vascular and peripheral nerve injury seen at the Emergency Room of Assir Central Hospital from 1990 to 1999. There were 39 males and four females. Thirty five of these patients (81.4%) were Saudi nationals and the rest were non-Saudi.

  7. B vitamins influence vascular cognitive impairment

    Science.gov (United States)

    As the number of elderly in the USA and globally continues to increase, age-related neurological disorders, such as Alzheimer's disease and vascular dementia, are a growing concern. The loss of memory, emotional changes, and impairments in general cognitive functioning frequently result in social is...

  8. Quality Estimation for Vascular Pattern Recognition

    DEFF Research Database (Denmark)

    Hartung, Daniel; Martin, Sophie; Busch, Christoph

    2011-01-01

    The quality of captured samples is a critical aspect in biometric systems. In this paper we present a quality estimation algorithm for vascular images, which uses global and local features based on a Grey Level Co-Occurrence Matrix (GLCM) and optionally available metadata. An evaluation of the al...

  9. Self-management of vascular risk factors

    NARCIS (Netherlands)

    Sol-de Rijk, B.G.M.

    2009-01-01

    Summary The aim of this thesis was to provide insight into the potential of a self-management approach in treatment of vascular risk factors and to develop a self-management intervention. Furthermore to examine if this intervention, based on self-efficacy promoting theory, is effective in reducing

  10. Human genetics of diabetic vascular complications

    Indian Academy of Sciences (India)

    Diabetic vascular complications (DVC) affecting several important organ systems of human body such as the cardiovascular system constitute a major public health problem. There is evidence demonstrating that genetic factors contribute to the risk of DVC genetic variants, structural variants, and epigenetic changes play ...

  11. CT imaging of cervical spinal vascular malformation

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, Takashi; Iwamoto, Munehisa; Miyamoto, Etsuo; Kuriyama, Tsuyoshi; Hayama, Tsuneto [Wakayama Red Cross Hospital, Wakayama (Japan)

    1982-05-01

    The patient had a history of the onset of motor paralysis of the right upper and lower extremities. Eight years later, numbness of the right upper extremity and a severe neck pain developed, and transverse paralysis of the lower extremities appeared in about 10 hours. CT demonstrated the presence of spinal vascular abnormality. Angiography suggested arteriovenous malformation of glomus type.

  12. Surgical correction of postoperative astigmatism

    Directory of Open Access Journals (Sweden)

    Lindstrom Richard

    1990-01-01

    Full Text Available The photokeratoscope has increased the understanding of the aspheric nature of the cornea as well as a better understanding of normal corneal topography. This has significantly affected the development of newer and more predictable models of surgical astigmatic correction. Relaxing incisions effectively flatten the steeper meridian an equivalent amount as they steepen the flatter meridian. The net change in spherical equivalent is, therefore, negligible. Poor predictability is the major limitation of relaxing incisions. Wedge resection can correct large degrees of postkeratoplasty astigmatism, Resection of 0.10 mm of tissue results in approximately 2 diopters of astigmatic correction. Prolonged postoperative rehabilitation and induced irregular astigmatism are limitations of the procedure. Transverse incisions flatten the steeper meridian an equivalent amount as they steepen the flatter meridian. Semiradial incisions result in two times the amount of flattening in the meridian of the incision compared to the meridian 90 degrees away. Combination of transverse incisions with semiradial incisions describes the trapezoidal astigmatic keratotomy. This procedure may correct from 5.5 to 11.0 diopters dependent upon the age of the patient. The use of the surgical keratometer is helpful in assessing a proper endpoint during surgical correction of astigmatism.

  13. Vascular Contributions to Cognitive Impairment and Dementia

    Science.gov (United States)

    Gorelick, Philip B.; Scuteri, Angelo; Black, Sandra E.; DeCarli, Charles; Greenberg, Steven M.; Iadecola, Costantino; Launer, Lenore J.; Laurent, Stephane; Lopez, Oscar L.; Nyenhuis, David; Petersen, Ronald C.; Schneider, Julie A.; Tzourio, Christophe; Arnett, Donna K.; Bennett, David A.; Chui, Helena C.; Higashida, Randall T.; Lindquist, Ruth; Nilsson, Peter M.; Roman, Gustavo C.; Sellke, Frank W.; Seshadri, Sudha

    2013-01-01

    Background and Purpose This scientific statement provides an overview of the evidence on vascular contributions to cognitive impairment and dementia. Vascular contributions to cognitive impairment and dementia of later life are common. Definitions of vascular cognitive impairment (VCI), neuropathology, basic science and pathophysiological aspects, role of neuroimaging and vascular and other associated risk factors, and potential opportunities for prevention and treatment are reviewed. This statement serves as an overall guide for practitioners to gain a better understanding of VCI and dementia, prevention, and treatment. Methods Writing group members were nominated by the writing group co-chairs on the basis of their previous work in relevant topic areas and were approved by the American Heart Association Stroke Council Scientific Statement Oversight Committee, the Council on Epidemiology and Prevention, and the Manuscript Oversight Committee. The writing group used systematic literature reviews (primarily covering publications from 1990 to May 1, 2010), previously published guidelines, personal files, and expert opinion to summarize existing evidence, indicate gaps in current knowledge, and, when appropriate, formulate recommendations using standard American Heart Association criteria. All members of the writing group had the opportunity to comment on the recommendations and approved the final version of this document. After peer review by the American Heart Association, as well as review by the Stroke Council leadership, Council on Epidemiology and Prevention Council, and Scientific Statements Oversight Committee, the statement was approved by the American Heart Association Science Advisory and Coordinating Committee. Results The construct of VCI has been introduced to capture the entire spectrum of cognitive disorders associated with all forms of cerebral vascular brain injury—not solely stroke—ranging from mild cognitive impairment through fully developed

  14. Pulmonary vascular input impedance is a combined measure of pulmonary vascular resistance and stiffness and predicts clinical outcomes better than pulmonary vascular resistance alone in pediatric patients with pulmonary hypertension.

    Science.gov (United States)

    Hunter, Kendall S; Lee, Po-Feng; Lanning, Craig J; Ivy, D Dunbar; Kirby, K Scott; Claussen, Lori R; Chan, K Chen; Shandas, Robin

    2008-01-01

    Pulmonary vascular resistance (PVR) is the current standard for evaluating reactivity in children with pulmonary arterial hypertension (PAH). However, PVR measures only the mean component of right ventricular afterload and neglects pulsatile effects. We recently developed and validated a method to measure pulmonary vascular input impedance, which revealed excellent correlation between the zero harmonic impedance value and PVR and suggested a correlation between higher-harmonic impedance values and pulmonary vascular stiffness. Here we show that input impedance can be measured routinely and easily in the catheterization laboratory, that impedance provides PVR and pulmonary vascular stiffness from a single measurement, and that impedance is a better predictor of disease outcomes compared with PVR. Pressure and velocity waveforms within the main pulmonary artery were measured during right heart catheterization of patients with normal pulmonary artery hemodynamics (n = 14) and those with PAH undergoing reactivity evaluation (49 subjects, 95 conditions). A correction factor needed to transform velocity into flow was obtained by calibrating against cardiac output. Input impedance was obtained off-line by dividing Fourier-transformed pressure and flow waveforms. Exceptional correlation was found between the indexed zero harmonic of impedance and indexed PVR (y = 1.095x + 1.381, R2 = 0.9620). In addition, the modulus sum of the first 2 harmonics of impedance was found to best correlate with indexed pulse pressure over stroke volume (y = 13.39x - 0.8058, R2 = 0.7962). Among a subset of patients with PAH (n = 25), cumulative logistic regression between outcomes to total indexed impedance was better (R(L)2 = 0.4012) than between outcomes and indexed PVR (R(L)2 = 0.3131). Input impedance can be consistently and easily obtained from pulse-wave Doppler and a single catheter pressure measurement, provides comprehensive characterization of the main components of RV afterload, and

  15. Corrections.

    Science.gov (United States)

    1994-05-27

    In "Women in Science: Some Books of the Year" (11 March, p. 1458) the name of the senior editor of second edition of The History of Women and Science, Health, and Technology should have been given as Phyllis Holman Weisbard, and the name of the editor of the first edition should have been given as Susan Searing. Also, the statement that the author of A Matter of Choices: Memoirs of a Female Physicist, Fay Ajzenberg-Selove, is now retired was incorrect.

  16. Corrections.

    Science.gov (United States)

    2016-02-01

    In the October In Our Unit article by Cooper et al, “Against All Odds: Preventing Pressure Ulcers in High-Risk Cardiac Surgery Patients” (Crit Care Nurse. 2015;35[5]:76–82), there was an error in the reference citation on page 82. At the top of that page, reference 18 cited on the second line should be reference 23, which also should be added to the References list: 23. AHRQ website. Prevention and treatment program integrates actionable reports into practice, significantly reducing pressure ulcers in nursing home residents. November 2008. https://innovations.ahrq.gov/profiles/prevention-and-treatment-program-integrates-actionable-reports-practice-significantly. Accessed November 18, 2015

  17. Correction.

    Science.gov (United States)

    2015-06-01

    Gillon R. Defending the four principles approach as a good basis for good medical practice and therefore for good medical ethics. J Med Ethics 2015;41:111–6. The author misrepresented Beauchamp and Childress when he wrote: ‘My own view (unlike Beauchamp and Childress who explicitly state that they make no such claim ( p. 421)1, is that all moral agents whether or not they are doctors or otherwise involved in healthcare have these prima facie moral obligations; but in the context of answering the question ‘what is it to do good medical ethics ?’ my claim is limited to the ethical obligations of doctors’. The author intended and should have written the following: ‘My own view, unlike Beauchamp and Childress who explicitly state that they make no such claim (p.421)1 is that these four prima facie principles can provide a basic moral framework not only for medical ethics but for ethics in general’.

  18. Correction.

    Science.gov (United States)

    2015-03-01

    In the January 2015 issue of Cyberpsychology, Behavior, and Social Networking (vol. 18, no. 1, pp. 3–7), the article "Individual Differences in Cyber Security Behaviors: An Examination of Who Is Sharing Passwords." by Prof. Monica Whitty et al., has an error in wording in the abstract. The sentence in question was originally printed as: Contrary to our hypotheses, we found older people and individuals who score high on self-monitoring were more likely to share passwords. It should read: Contrary to our hypotheses, we found younger people and individuals who score high on self-monitoring were more likely to share passwords. The authors wish to apologize for the error.

  19. Correction

    CERN Multimedia

    2007-01-01

    From left to right: Luis, Carmen, Mario, Christian and José listening to speeches by theorists Alvaro De Rújula and Luis Alvarez-Gaumé (right) at their farewell gathering on 15 May.We unfortunately cut out a part of the "Word of thanks" from the team retiring from Restaurant No. 1. The complete message is published below: Dear friends, You are the true "nucleus" of CERN. Every member of this extraordinary human mosaic will always remain in our affections and in our thoughts. We have all been very touched by your spontaneous generosity. Arrivederci, Mario Au revoir,Christian Hasta Siempre Carmen, José and Luis PS: Lots of love to the theory team and to the hidden organisers. So long!

  20. Correction

    Science.gov (United States)

    2014-01-01

    In the meeting report "Strategies to observe and understand processes and drivers in the biogeosphere," published in the 14 January 2014 issue of Eos (95(2), 16, doi:10.1002/2014EO020004), an incorrect affiliation was listed for one coauthor. Michael Young is with the University of Texas at Austin.

  1. Coexistence of pheochromocytoma with uncommon vascular lesions

    Directory of Open Access Journals (Sweden)

    Sunil Kumar Kota

    2012-01-01

    Full Text Available Background: Pheochromocytoma/paragangliomas have been described to be associated with rare vascular abnormalities like renal artery stenosis. Coexistence of physiologically significant renal artery lesions is a compounding factor that alters management and prognosis of pheochromocytoma patients. Apart from individual case reports, data on such association in Indian population is not available. The aim of this study is to find the nature and prevalence of associated vascular abnormalities. Materials and Methods: From 1990 to 2010, a total of 50 patients were diagnosed with pheochromocytoma/paragangliomas. Hospital charts of these patients were reviewed retrospectively to identify those with unusual vascular abnormalities. Available literature was also reviewed. Results: Of the 50 patients with pheochromocytoma, 7 (14% had coexisting vascular lesions including renal artery stenosis in 4, aortoarteritis in 1, aortic aneurysm in 1 and inferior vena cava thrombosis in 1. Pheochromocytoma was adrenal in 42 and extra adrenal in 8. Laparoscopic adrenalectomy was done in the patients. One patient with renal artery stenosis due to intimal fibrosis was subjected to percutaneous balloon angioplasty; the other three improved after adrenalectomy and lysis of fibrous adhesive bands. The patient with aortoarteritos was treated with oral steroids. Inferior vena cava thrombosis was reversed with anticoagulants. The patient with abdominal aortic aneurysm was advised for annual follow-up on account of its size of 4.5 cm and asymptomatic presentation. Conclusion: There are multiple mechanisms that can lead to renal artery stenosis and other vascular abnormalities in a case of pheochromocytoma. A high index of suspicion is necessary to enable both entities to be diagnosed preoperatively and allow proper planning of surgical therapy. Incomplete diagnosis may lead to persistent hypertension postoperatively in a case of associated renal artery stenosis.

  2. The making of indigenous vascular prosthesis

    Directory of Open Access Journals (Sweden)

    Madathipat Unnikrishnan

    2016-01-01

    Full Text Available Background & objectives: Vascular illnesses are on the rise in India, due to increase in lifestyle diseases and demographic transition, requiring intervention to save life, organ or limbs using vascular prosthesis. The aim of this study was to develop indigenous large diameter vascular graft for treatment of patients with vascular pathologies. Methods: The South India Textile Research Association, at Coimbatore, Tamil Nadu, India, developed seamless woven polyester (Polyethylene terephthalate graft at its research wing. Further characterization and testing followed by clinical trials were conducted at Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India. Fifteen in vivo experiments were carried out in 1992-1994 in pigs as animal model. Controlled (phase I clinical trial in ten patients was performed along with control graft. Thereafter, phase II trial involved 22 patients who underwent multi-centre clinical trial in four centres across India. Results: Laboratory testing showed that polyester graft was non-toxic, non-leeching and non-haemolytic with preserved long-term quality, further confirming in pigs by implanting in thoracic aorta, comparable to control Dacron grafts. Perigraft incorporation and smooth neointima formation which are prime features of excellent healing characteristics, were noted at explantation at planned intervals. Subsequently in the phase I and II clinical trials, all patients had excellent recovery without mortality or device-related adverse events. Patients receiving the test graft were followed up for 10 and 5 years, respectively. Serial clinical, duplex scans and CT angiograms performed periodically confirmed excellent graft performance. Interpretation & conclusions: Indigenously developed Chitra vascular graft was comparable to commercially available Dacron graft, ready for clinical use at affordable cost to patients as against costly imported grafts.

  3. A biodegradable vascularizing membrane: a feasibility study.

    Science.gov (United States)

    Kaushiva, Anchal; Turzhitsky, Vladimir M; Darmoc, Marissa; Backman, Vadim; Ameer, Guillermo A

    2007-09-01

    Regenerative medicine and in vivo biosensor applications require the formation of mature vascular networks for long-term success. This study investigated whether biodegradable porous membranes could induce the formation of a vascularized fibrous capsule and, if so, the effect of degradation kinetics on neovascularization. Poly(l-lactic acid) (PLLA) and poly(dl-lactic-co-glycolic) acid (PLGA) membranes were created by a solvent casting/salt leaching method. Specifically, PLLA, PLGA 75:25 and PLGA 50:50 polymers were used to vary degradation kinetics. The membranes were designed to have an average 60mum pore diameter, as this pore size has been shown to be optimal for inducing blood vessel formation around nondegradable polymer materials. Membrane samples were imaged by scanning electron microscopy at several time points during in vitro degradation to assess any changes in pore structure. The in vivo performance of the membranes was assessed in Sprague-Dawley rats by measuring vascularization within the fibrous capsule that forms adjacent to implants. The vascular density within 100microm of the membranes was compared with that seen in normal tissue, and to that surrounding the commercially available vascularizing membrane TheraCyte. The hemoglobin content of tissue containing the membranes was measured by four-dimensional elastic light scattering as a novel method to assess tissue perfusion. Results from this study show that slow-degrading membranes induce greater amounts of neovascularization and a thinner fibrous capsule relative to fast degrading membranes. These results may be due both to an initially increased number of macrophages surrounding the slower degrading membranes and to the maintenance of their initial pore structure.

  4. Advanced Maternal Age Worsens Postpartum Vascular Function

    Directory of Open Access Journals (Sweden)

    Jude S. Morton

    2017-06-01

    Full Text Available The age at which women experience their first pregnancy has increased throughout the decades. Pregnancy has an important influence on maternal short- and long-term cardiovascular outcomes. Pregnancy at an advanced maternal age increases maternal risk of gestational diabetes, preeclampsia, placenta previa and caesarian delivery; complications which predict worsened cardiovascular health in later years. Aging also independently increases the risk of cardiovascular disease; therefore, combined risk in women of advanced maternal age may lead to detrimental cardiovascular outcomes later in life. We hypothesized that pregnancy at an advanced maternal age would lead to postpartum vascular dysfunction. We used a reproductively aged rat model to investigate vascular function in never pregnant (virgin, previously pregnant (postpartum and previously mated but never delivered (nulliparous rats at approximately 13.5 months of age (3 months postpartum or equivalent. Nulliparous rats, in which pregnancy was spontaneously lost, demonstrated significantly reduced aortic relaxation responses (methylcholine [MCh] Emax: 54.2 ± 12.6% vs. virgin and postpartum rats (MCh Emax: 84.8 ± 3.5% and 84.7 ± 3.2% respectively; suggesting pregnancy loss causes a worsened vascular pathology. Oxidized LDL reduced relaxation to MCh in aorta from virgin and postpartum, but not nulliparous rats, with an increased contribution of the LOX-1 receptor in the postpartum group. Further, in mesenteric arteries from postpartum rats, endothelium-derived hyperpolarization (EDH-mediated vasodilation was reduced and a constrictive prostaglandin effect was apparent. In conclusion, aged postpartum rats exhibited vascular dysfunction, while rats which had pregnancy loss demonstrated a distinct vascular pathology. These data demonstrate mechanisms which may lead to worsened outcomes at an advanced maternal age; including early pregnancy loss and later life cardiovascular dysfunction.

  5. Usefulness of magnetic resonance angiography in diagnosis of peripheral vascular disease

    International Nuclear Information System (INIS)

    Kuga, Takayuki; Akiyama, Norio; Takenaka, Hiroaki; Fujioka, Kentaro; Zempo, Noriya; Esato, Kensuke

    1992-01-01

    The diagnostic usefulness of magnetic resonance angiography (MRA) was evaluated in 19 patients with peripheral vascular disease. It takes thirty minutes or less to perform this test, without any complications. The percent of correct diagnosis on obstructive and stenotic region was 75% in cases of deep vein thrombosis. In addition, it was easy to diagnose an existence of a graft patent. However, it was unsatisfactory to understand morphologic changes of an iliac artery and to determine the position of grafting. The position and size of dilatation and existence of thrombus were easily evaluated in patients with venous aneurysm and varicose vein. MRA was a non-invasive, short spending time imaging. It was available for pregnant women and people with drug allergy, heart failure or renal failure. We believe that MRA can be used in the preoperative examination and the evaluation of the postoperative complications in the peripheral vascular diseases. (J.P.N.)

  6. Repair of a mandibular defect with a free vascularized coccygeal vertebra transfer in a dog.

    Science.gov (United States)

    Yeh, L S; Hou, S M

    1994-01-01

    Bilateral mandibular defects in a male mongrel dog were repaired. On the left side, a free vascularized coccygeal bone graft that included the median caudal artery and caudal vein was used to correct the defect. On the right side, the defect was bridged with a bone plate and screws. For further immobilization, the muzzle was temporarily taped for 3 weeks and a pharyngostomy tube was used for nutritional support. The dog was able to eat dry commercial food satisfactorily within 2 months of surgery despite mild malocclusion. Radiographs taken 2 months and 18 months postoperatively showed bony union with graft hypertrophy in the left mandible, whereas the right mandibular defect showed protracted nonunion. The results indicate that vascularized coccygeal vertebra transfer provides an alternative for the management of canine mandibular defects.

  7. Usefulness of magnetic resonance angiography in diagnosis of peripheral vascular disease

    Energy Technology Data Exchange (ETDEWEB)

    Kuga, Takayuki; Akiyama, Norio; Takenaka, Hiroaki; Fujioka, Kentaro; Zempo, Noriya; Esato, Kensuke (Yamaguchi Univ., Ube (Japan). School of Medicine)

    1992-03-01

    The diagnostic usefulness of magnetic resonance angiography (MRA) was evaluated in 19 patients with peripheral vascular disease. It takes thirty minutes or less to perform this test, without any complications. The percent of correct diagnosis on obstructive and stenotic region was 75% in cases of deep vein thrombosis. In addition, it was easy to diagnose an existence of a graft patent. However, it was unsatisfactory to understand morphologic changes of an iliac artery and to determine the position of grafting. The position and size of dilatation and existence of thrombus were easily evaluated in patients with venous aneurysm and varicose vein. MRA was a non-invasive, short spending time imaging. It was available for pregnant women and people with drug allergy, heart failure or renal failure. We believe that MRA can be used in the preoperative examination and the evaluation of the postoperative complications in the peripheral vascular diseases. (J.P.N.).

  8. Universality of quantum gravity corrections.

    Science.gov (United States)

    Das, Saurya; Vagenas, Elias C

    2008-11-28

    We show that the existence of a minimum measurable length and the related generalized uncertainty principle (GUP), predicted by theories of quantum gravity, influence all quantum Hamiltonians. Thus, they predict quantum gravity corrections to various quantum phenomena. We compute such corrections to the Lamb shift, the Landau levels, and the tunneling current in a scanning tunneling microscope. We show that these corrections can be interpreted in two ways: (a) either that they are exceedingly small, beyond the reach of current experiments, or (b) that they predict upper bounds on the quantum gravity parameter in the GUP, compatible with experiments at the electroweak scale. Thus, more accurate measurements in the future should either be able to test these predictions, or further tighten the above bounds and predict an intermediate length scale between the electroweak and the Planck scale.

  9. String-Corrected Black Holes

    Energy Technology Data Exchange (ETDEWEB)

    Hubeny, V.

    2005-01-12

    We investigate the geometry of four dimensional black hole solutions in the presence of stringy higher curvature corrections to the low energy effective action. For certain supersymmetric two charge black holes these corrections drastically alter the causal structure of the solution, converting seemingly pathological null singularities into timelike singularities hidden behind a finite area horizon. We establish, analytically and numerically, that the string-corrected two-charge black hole metric has the same Penrose diagram as the extremal four-charge black hole. The higher derivative terms lead to another dramatic effect--the gravitational force exerted by a black hole on an inertial observer is no longer purely attractive. The magnitude of this effect is related to the size of the compactification manifold.

  10. Endovascular Management of Vascular Injury during Transsphenoidal Surgery

    OpenAIRE

    Çinar, C.; Bozkaya, H.; Parildar, M.; Oran, I.

    2013-01-01

    Vascular injury is an unusual and serious complication of transsphenoidal surgery. We aimed to define the role of angiography and endovascular treatment in patients with vascular injuries occurring during transsphenoidal surgery.

  11. Vascular effects of a single high salt meal

    Directory of Open Access Journals (Sweden)

    Mohamed Abdel Kader Abdel Wahab

    2016-09-01

    Conclusion: High salt intake may acutely impair vascular function in different vascular beds independent of the increase of blood pressure. Plasma sodium increase may be one of the underlying mechanisms.

  12. Vascular surgery research in the Gulf Cooperation Council countries

    Directory of Open Access Journals (Sweden)

    Ali Jawas

    2014-04-01

    Conclusion: The quality and quantity of vascular surgery research in the GCC countries should be improved to answer important local questions related to vascular diseases. This needs better strategic planning and more collaboration between various institutions.

  13. Estrogen, vascular estrogen receptor and hormone therapy in postmenopausal vascular disease.

    Science.gov (United States)

    Khalil, Raouf A

    2013-12-15

    Cardiovascular disease (CVD) is less common in premenopausal women than men of the same age or postmenopausal women, suggesting vascular benefits of estrogen. Estrogen activates estrogen receptors ERα, ERβ and GPR30 in endothelium and vascular smooth muscle (VSM), which trigger downstream signaling pathways and lead to genomic and non-genomic vascular effects such as vasodilation, decreased VSM contraction and growth and reduced vascular remodeling. However, randomized clinical trials (RCTs), such as the Women's Health Initiative (WHI) and Heart and Estrogen/progestin Replacement Study (HERS), have shown little vascular benefits and even adverse events with menopausal hormone therapy (MHT), likely due to factors related to the MHT used, ER profile, and RCT design. Some MHT forms, dose, combinations or route of administration may have inadequate vascular effects. Age-related changes in ER amount, distribution, integrity and post-ER signaling could alter the vascular response to MHT. The subject's age, preexisting CVD, and hormone environment could also reduce the effects of MHT. Further evaluation of natural and synthetic estrogens, phytoestrogens, and selective estrogen-receptor modulators (SERMs), and the design of appropriate MHT combinations, dose, route and 'timing' could improve the effectiveness of conventional MHT and provide alternative therapies in the peri-menopausal period. Targeting ER using specific ER agonists, localized MHT delivery, and activation of specific post-ER signaling pathways could counter age-related changes in ER. Examination of the hormone environment and conditions associated with hormone imbalance such as polycystic ovary syndrome may reveal the causes of abnormal hormone-receptor interactions. Consideration of these factors in new RCTs such as the Kronos Early Estrogen Prevention Study (KEEPS) could enhance the vascular benefits of estrogen in postmenopausal CVD. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Cell sheet engineering using the stromal vascular fraction of adipose tissue as a vascularization strategy

    OpenAIRE

    Costa, M.; Cerqueira, Mariana Teixeira; Santos, T. C.; Marques, Belém Sampaio; Ludovico, Paula; Marques, A. P.; Pirraco, Rogério P.; Reis, R. L.

    2017-01-01

    Current vascularization strategies for Tissue Engineering constructs, in particular cell sheet-based, are limited by time-consuming and expensive endothelial cell isolation and/or by the complexity of using extrinsic growth factors. Herein, we propose an alternative strategy using angiogenic cell sheets (CS) obtained from the stromal vascular fraction (SVF) of adipose tissue that can be incorporated into more complex constructs. Cells from the SVF were cultured in normoxic and hypoxic conditi...

  15. SELF CORRECTION WORKS BETTER THAN TEACHER CORRECTION IN EFL SETTING

    Directory of Open Access Journals (Sweden)

    Azizollah Dabaghi

    2012-11-01

    Full Text Available Learning a foreign language takes place step by step, during which mistakes are to be expected in all stages of learning. EFL learners are usually afraid of making mistakes which prevents them from being receptive and responsive. Overcoming fear of mistakes depends on the way mistakes are rectified. It is believed that autonomy and learner-centeredness suggest that in some settings learner's self-correction of mistakes might be more beneficial for language learning than teacher's correction. This assumption has been the subject of debates for some time. Some researchers believe that correction whether that of teacher's or on behalf of learners is effective in showing them how their current interlanguage differs from the target (Long &Robinson, 1998. Others suggest that correcting the students whether directly or through recasts are ambiguous and may be perceived by the learner as confirmation of meaning rather than feedback on form (Lyster, 1998a. This study is intended to investigate the effects of correction on Iranian intermediate EFL learners' writing composition in Payam Noor University. For this purpose, 90 English majoring students, studying at Isfahan Payam Noor University were invited to participate at the experiment. They all received a sample of TOFEL test and a total number of 60 participants whose scores were within the range of one standard deviation below and above the mean were divided into two equal groups; experimental and control. The experimental group went through some correction during the experiment while the control group remained intact and the ordinary processes of teaching went on. Each group received twelve sessions of two hour classes every week on advanced writing course in which some activities of Modern English (II were selected. Then after the treatment both groups received an immediate test as post-test and the experimental group took the second post-test as the delayed recall test with the same design as the

  16. The use of 3D computer graphics in the diagnosis and treatment of spinal vascular malformations.

    Science.gov (United States)

    Takai, Keisuke; Kin, Taichi; Oyama, Hiroshi; Iijima, Akira; Shojima, Masaaki; Nishido, Hajime; Saito, Nobuhito

    2011-12-01

    Digital subtraction (DS) angiography is the gold standard for diagnosing spinal vascular malformations. Recently, multidetectorrow spiral CT and contrast-enhanced MR angiography have been introduced as screening examinations before DS angiography. These methods, however, do not always determine the accurate location of an arteriovenous shunt because the resulting images lack information about the spinal cord or the dura mater. Between April 2009 and December 2010, 13 patients underwent imaging evaluations for spinal vascular malformations at the authors' university hospital. This group included 8 patients with spinal dural arteriovenous fistulas (AVFs), 3 with perimedullary AVFs, and 2 with intramedullary arteriovenous malformations. Using data from these patients, the authors attempted to develop 3D computer graphics (CG) based upon the fusion of 3D rotational angiography and postmyelographic CT. They subsequently verified the accuracy of this imaging method. Ten of these 13 patients underwent surgical treatment for their lesions (11 AVFs), and for these 11 lesions the authors compared the diagnoses obtained using 3D CG with those obtained using conventional DS angiography. In all 13 cases, 3D CG images of the spinal lesions were successfully developed using the patients' actual data. Four (36%) of 11 AVFs were correctly identified using DS angiography, whereas 10 (91%) were correctly identified using 3D CG. Results from 3D CG of spinal AVFs corresponded well with operative findings, and 3D CG was significantly better than conventional DS angiography at predicting AVF location (p = 0.024, Fisher exact test). To the authors' knowledge, this is the first reported case series in which 3D CG of spinal vascular malformations was used to provide simultaneous, stereoscopic visualization of the spinal vascular system, spinal cord, dura mater, and bone. The 3D CG method provides precise visual images for the diagnosis and treatment of these lesions.

  17. Correcting quantum errors with entanglement.

    Science.gov (United States)

    Brun, Todd; Devetak, Igor; Hsieh, Min-Hsiu

    2006-10-20

    We show how entanglement shared between encoder and decoder can simplify the theory of quantum error correction. The entanglement-assisted quantum codes we describe do not require the dual-containing constraint necessary for standard quantum error-correcting codes, thus allowing us to "quantize" all of classical linear coding theory. In particular, efficient modern classical codes that attain the Shannon capacity can be made into entanglement-assisted quantum codes attaining the hashing bound (closely related to the quantum capacity). For systems without large amounts of shared entanglement, these codes can also be used as catalytic codes, in which a small amount of initial entanglement enables quantum communication.

  18. Self-correcting Multigrid Solver

    International Nuclear Information System (INIS)

    Lewandowski, Jerome L.V.

    2004-01-01

    A new multigrid algorithm based on the method of self-correction for the solution of elliptic problems is described. The method exploits information contained in the residual to dynamically modify the source term (right-hand side) of the elliptic problem. It is shown that the self-correcting solver is more efficient at damping the short wavelength modes of the algebraic error than its standard equivalent. When used in conjunction with a multigrid method, the resulting solver displays an improved convergence rate with no additional computational work

  19. Brane cosmology with curvature corrections

    International Nuclear Information System (INIS)

    Kofinas, Georgios; Maartens, Roy; Papantonopoulos, Eleftherios

    2003-01-01

    We study the cosmology of the Randall-Sundrum brane-world where the Einstein-Hilbert action is modified by curvature correction terms: a four-dimensional scalar curvature from induced gravity on the brane, and a five-dimensional Gauss-Bonnet curvature term. The combined effect of these curvature corrections to the action removes the infinite-density big bang singularity, although the curvature can still diverge for some parameter values. A radiation brane undergoes accelerated expansion near the minimal scale factor, for a range of parameters. This acceleration is driven by the geometric effects, without an inflation field or negative pressures. At late times, conventional cosmology is recovered. (author)

  20. Deficiency of superoxide dismutase promotes cerebral vascular hypertrophy and vascular dysfunction in hyperhomocysteinemia.

    Directory of Open Access Journals (Sweden)

    Sanjana Dayal

    Full Text Available There is an emerging consensus that hyperhomocysteinemia is an independent risk factor for cerebral vascular disease and that homocysteine-lowering therapy protects from ischemic stroke. However, the mechanisms by which hyperhomocysteinemia produces abnormalities of cerebral vascular structure and function remain largely undefined. Our objective in this study was to define the mechanistic role of superoxide in hyperhomocysteinemia-induced cerebral vascular dysfunction and hypertrophy. Unlike previous studies, our experimental design included a genetic approach to alter superoxide levels by using superoxide dismutase 1 (SOD1-deficient mice fed a high methionine/low folate diet to produce hyperhomocysteinemia. In wild-type mice, the hyperhomocysteinemic diet caused elevated superoxide levels and impaired responses to endothelium-dependent vasodilators in cerebral arterioles, and SOD1 deficiency compounded the severity of these effects. The cross-sectional area of the pial arteriolar wall was markedly increased in mice with SOD1 deficiency, and the hyperhomocysteinemic diet sensitized SOD1-deficient mice to this hypertrophic effect. Analysis of individual components of the vascular wall demonstrated a significant increase in the content of smooth muscle and elastin. We conclude that superoxide is a key driver of both cerebral vascular hypertrophy and vasomotor dysfunction in this model of dietary hyperhomocysteinemia. These findings provide insight into the mechanisms by which hyperhomocysteinemia promotes cerebral vascular disease and ischemic stroke.

  1. Using biplanar fluoroscopy to guide radiopaque vascular injections: a new method for vascular imaging.

    Directory of Open Access Journals (Sweden)

    Haley D O'Brien

    Full Text Available Studying vascular anatomy, especially in the context of relationships with hard tissues, is of great interest to biologists. Vascular studies have provided significant insight into physiology, function, phylogenetic relationships, and evolutionary patterns. Injection of resin or latex into the vascular system has been a standard technique for decades. There has been a recent surge in popularity of more modern methods, especially radiopaque latex vascular injection followed by CT scanning and digital "dissection." This technique best displays both blood vessels and bone, and allows injections to be performed on cadaveric specimens. Vascular injection is risky, however, because it is not a standardizable technique, as each specimen is variable with regard to injection pressure and timing. Moreover, it is not possible to view the perfusion of injection medium throughout the vascular system of interest. Both data and rare specimens can therefore be lost due to poor or excessive perfusion. Here, we use biplanar video fluoroscopy as a technique to guide craniovascular radiopaque latex injection. Cadaveric domestic pigs (Sus scrofa domestica and white-tailed deer (Odocoileus virginianus were injected with radiopaque latex under guidance of fluoroscopy. This method was found to enable adjustments, in real-time, to the rate, location, and pressure at which latex is injected in order to avoid data and specimen loss. In addition to visualizing the injection process, this technique can be used to determine flow patterns, and has facilitated the development of consistent markers for complete perfusion.

  2. Joint Global War on Terror (GWOT) Vascular Injury Study 2

    Science.gov (United States)

    2017-02-01

    acquired in Iraq and Afghanistan, Society for Trauma Nurse, 2-4 April 2014, poster presentation o Vascular discharge education and follow-up care...eventual quality of limb and psychological recovery or well-being. 15. SUBJECT TERMS extremity vascular injury, extremity, vascular injury, vascular... psychological recovery or well-being. Finally, this program aims to characterize and compare the physical and emotional burden in large cohorts of US

  3. Elimination of the induced malfunctions and use of dynamic prognosis in a thermodynamic diagnosis system of the thermal cycling; Eliminacao das malfuncoes induzidas e utilizacao do prognostico dinamico em sistemas de diagnostico termodinamico de ciclos termicos

    Energy Technology Data Exchange (ETDEWEB)

    Silva, J.A.M.; Venturini, O.J.; Lora, E.E.S. [Universidade Federal de Itajuba (NEST/IEM/UNIFEI), MG (Brazil). Inst. de Engenharia Mecanica. Nucleo de Excelencia em Geracao Termeletrica e Distribuida], Emails: juliomendes@unifei.edu.br, osvaldo@unifei.edu.br, electo@unifei.edu.br

    2009-07-01

    The search for more efficient thermal cycles has led a growing complexity of these cycles and therefore increased the inter-relationships between the thermodynamic components. This complexity is further enhanced with the over time, due to the occurrence of both natural as early degradation in a more or less degree, of all plant components. Several methodologies have been proposed for creating system for diagnostic / prognostic with the objective to detect these degradations (defects) and quantify the gain that can be obtained in the performance indicators of thermal cycles (usually specific fuel consumption and power net) by the elimination of anomalies. Two points have been emphasized as the most difficult in the development of such systems: the distinction between the performance variation of the components due only to the point of operation outside of these project components, caused by the presence of abnormality in another component (induced malfunction) and a decrease in the performance due to the presence of anomalies in the component itself (intrinsic malfunction). The second difficulty is the quantification of the effects induced by the elimination of each of the present anomalies. This work makes use of the method of reconciliation and using individual models of each component to predict unusual behavior of the same design point. The comparison of data from the system plant information, relating to the current state and data from the models, is used to detect anomalies. The methodology is explained in detail and an application of it in a Rankine cycle is used to well understand, especially in parts for the elimination of induced malfunctions, and related to the induced changes by the elimination of each one of the anomalies.

  4. Childhood Vascular Tumors Treatment (PDQ®)—Patient Version

    Science.gov (United States)

    Childhood vascular tumors form from cells that make blood vessels or lymph vessels. They can be benign (not cancer) or malignant (cancer). Get information about the symptoms, tests to diagnose, prognosis, and treatment of the most common type of vascular tumor, infantile hemangioma, and other vascular tumors in this expert-reviewed summary.

  5. The evolution of development of vascular cambia and secondary growth

    Science.gov (United States)

    Andrew Groover; Rachel Spicer

    2010-01-01

    Secondary growth from vascular cambia results in radial, woody growth of stems. The innovation of secondary vascular development during plant evolution allowed the production of novel plant forms ranging from massive forest trees to flexible, woody lianas. We present examples of the extensive phylogenetic variation in secondary vascular growth and discuss current...

  6. Management of vascular trauma from dog bites.

    Science.gov (United States)

    Akingba, A George; Robinson, Eric A; Jester, Andrea L; Rapp, Brian M; Tsai, Anthony; Motaganahalli, Raghu L; Dalsing, Michael C; Murphy, Michael P

    2013-11-01

    Vascular trauma from large-dog bites present with a combination of crush and lacerating injuries to the vessel, as well as significant adjacent soft tissue injury and a high potential for wound complications. This retrospective case series evaluates our 15 years of experience in managing this uncommonly seen injury into suggested treatment recommendations. From our database, 371 adult patients presented with dog bites between July 1997 and June 2012. Twenty (5.4%) of those patients had vascular injuries requiring surgical intervention. Patient demographics, anatomic location of injury, clinical presentation, imaging modality, method of repair, and complication rates were reviewed to assess efficacy in preserving limb function. Pediatric patients were managed at the regional children's hospital and, therefore, not included in this study. Among the 20 surgically treated vascular injuries, there were 13 arterial-only injuries, two venous-only injuries, and five combination arterial and venous injuries. Seventeen patients (85%) had upper extremity injuries; three patients had lower extremity injuries (15%). The axillobrachial artery was the most commonly injured single vessel (n = 9/20; 45%), followed by the radial artery (n = 4/20; 20%). Surgical repair of vascular injuries consisted of resection and primary anastomosis (four), interposition bypass of artery with autogenous vein (13), and ligation (two), with (one) being a combination of bypass and ligation. All patients had debridement of devitalized tissue combined with pulse lavage irrigation and perioperative antibiotics. Associated injuries requiring repair included muscle and skin (n = 10/20; 50%), bone (n = 1/20; 5%), nerve (n = 1/20; 5%), and combinations of the three (n = 5/20; 25%). Postoperative antibiotic therapy was administered for 14.7 ± 8.2 days in all 20 patients. Four patients (20%) developed postoperative wound infections, although this did not compromise their vascular repair. Of the patients

  7. A Generalized Correction for Attenuation.

    Science.gov (United States)

    Petersen, Anne C.; Bock, R. Darrell

    Use of the usual bivariate correction for attenuation with more than two variables presents two statistical problems. This pairwise method may produce a covariance matrix which is not at least positive semi-definite, and the bivariate procedure does not consider the possible influences of correlated errors among the variables. The method described…

  8. Entropic corrections to Newton's law

    International Nuclear Information System (INIS)

    Setare, M R; Momeni, D; Myrzakulov, R

    2012-01-01

    In this short paper, we calculate separately the generalized uncertainty principle (GUP) and self-gravitational corrections to Newton's gravitational formula. We show that for a complete description of the GUP and self-gravity effects, both the temperature and entropy must be modified. (paper)

  9. 'Correction of unrealizable service choreographies’

    NARCIS (Netherlands)

    Mancioppi, M.

    2015-01-01

    This thesis is devoted to the detection and correction of design flaws affecting service choreographies. Service choreographies are models that specify how software services are composed in a decentralized, message-driven fashion. In particular, this work focuses on flaws that compromise the

  10. Multilingual text induced spelling correction

    NARCIS (Netherlands)

    Reynaert, M.W.C.

    2004-01-01

    We present TISC, a multilingual, language-independent and context-sensitive spelling checking and correction system designed to facilitate the automatic removal of non-word spelling errors in large corpora. Its lexicon is derived from raw text corpora, without supervision, and contains word unigrams

  11. The correct "ball bearings" data.

    Science.gov (United States)

    Caroni, C

    2002-12-01

    The famous data on fatigue failure times of ball bearings have been quoted incorrectly from Lieblein and Zelen's original paper. The correct data include censored values, as well as non-fatigue failures that must be handled appropriately. They could be described by a mixture of Weibull distributions, corresponding to different modes of failure.

  12. Interaction and self-correction

    DEFF Research Database (Denmark)

    Satne, Glenda Lucila

    2014-01-01

    and acquisition. I then criticize two models that have been dominant in thinking about conceptual competence, the interpretationist and the causalist models. Both fail to meet NC, by failing to account for the abilities involved in conceptual self-correction. I then offer an alternative account of self...

  13. CORRECTIVE ACTION IN CAR MANUFACTURING

    Directory of Open Access Journals (Sweden)

    H. Rohne

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: In this paper the important .issues involved in successfully implementing corrective action systems in quality management are discussed. The work is based on experience in implementing and operating such a system in an automotive manufacturing enterprise in South Africa. The core of a corrective action system is good documentation, supported by a computerised information system. Secondly, a systematic problem solving methodology is essential to resolve the quality related problems identified by the system. In the following paragraphs the general corrective action process is discussed and the elements of a corrective action system are identified, followed by a more detailed discussion of each element. Finally specific results from the application are discussed.

    AFRIKAANSE OPSOMMING: Belangrike oorwegings by die suksesvolle implementering van korrektiewe aksie stelsels in gehaltebestuur word in hierdie artikel bespreek. Die werk is gebaseer op ondervinding in die implementering en bedryf van so 'n stelsel by 'n motorvervaardiger in Suid Afrika. Die kern van 'n korrektiewe aksie stelsel is goeie dokumentering, gesteun deur 'n gerekenariseerde inligtingstelsel. Tweedens is 'n sistematiese probleemoplossings rnetodologie nodig om die gehalte verwante probleme wat die stelsel identifiseer aan te spreek. In die volgende paragrawe word die algemene korrektiewe aksie proses bespreek en die elemente van die korrektiewe aksie stelsel geidentifiseer. Elke element word dan in meer besonderhede bespreek. Ten slotte word spesifieke resultate van die toepassing kortliks behandel.

  14. Rank error-correcting pairs

    DEFF Research Database (Denmark)

    Martinez Peñas, Umberto; Pellikaan, Ruud

    2017-01-01

    Error-correcting pairs were introduced as a general method of decoding linear codes with respect to the Hamming metric using coordinatewise products of vectors, and are used for many well-known families of codes. In this paper, we define new types of vector products, extending the coordinatewise ...

  15. Multinephron dynamics on the renal vascular network

    DEFF Research Database (Denmark)

    Marsh, Donald J; Wexler, Anthony S; Brazhe, Alexey

    2012-01-01

    Tubuloglomerular feedback (TGF) and the myogenic mechanism combine in each nephron to regulate blood flow and glomerular filtration rate. Both mechanisms are non-linear, generate self-sustained oscillations, and interact as their signals converge on arteriolar smooth muscle, forming a regulatory...... clusters. In-phase synchronization predominated among nephrons separated by 1 or 3 vascular nodes, and anti-phase synchronization for 5 or 7 nodes of separation. Nephron dynamics were irregular and contained low frequency fluctuations. Results are consistent with simultaneous blood flow measurements...... of both mechanisms in the regulatory ensemble, to examine the effects of network structure on nephron synchronization. Symmetry, as a property of a network, facilitates synchronization. Nephrons received blood from a symmetric electrically conductive vascular tree. Symmetry was created by using identical...

  16. Cocoa, Blood Pressure, and Vascular Function

    Science.gov (United States)

    Ludovici, Valeria; Barthelmes, Jens; Nägele, Matthias P.; Enseleit, Frank; Ferri, Claudio; Flammer, Andreas J.; Ruschitzka, Frank; Sudano, Isabella

    2017-01-01

    Cardiovascular disease (CVD) represents the most common cause of death worldwide. The consumption of natural polyphenol-rich foods, and cocoa in particular, has been related to a reduced risk of CVD, including coronary heart disease and stroke. Intervention studies strongly suggest that cocoa exerts a beneficial impact on cardiovascular health, through the reduction of blood pressure (BP), improvement of vascular function, modulation of lipid and glucose metabolism, and reduction of platelet aggregation. These potentially beneficial effects have been shown in healthy subjects as well as in patients with risk factors (arterial hypertension, diabetes, and smoking) or established CVD (coronary heart disease or heart failure). Several potential mechanisms are supposed to be responsible for the positive effect of cocoa; among them activation of nitric oxide (NO) synthase, increased bioavailability of NO as well as antioxidant, and anti-inflammatory properties. It is the aim of this review to summarize the findings of cocoa and chocolate on BP and vascular function. PMID:28824916

  17. Vascular anatomy of the spinal cord

    International Nuclear Information System (INIS)

    Thron, A.K.

    1988-01-01

    The book summarizes the anatomic guidelines of external blood supply to the spinal cord. The basic principles of arterial supply and venous drainage are illustrated by explicit schemes for quick orientation. In the first part of the book, systematic radiologic-anatomic investigations of the superficial and deep vessels of all segments of the spinal cord are introduced. The microvascular morphology is portrayed by numerous microradiographic sections in all three dimensions without overshadowing. The three-dimensional representation of the vascular architecture illustrates elementary outlines and details of arterial territories, anastomotic cross-linking as well as the capillary system, particularly the hitherto unknown structure of the medullary venous system with its functionally important anastomoses and varying regional structures. These often now radiologic-anatomic findings are discussed as to their functional and pathophysiologic impact and constitute the basic on which to improve one's understanding of vascular syndromes of the spinal cord

  18. Features and selection of vascular access devices.

    Science.gov (United States)

    Sansivero, Gail Egan

    2010-05-01

    To review venous anatomy and physiology, discuss assessment parameters before vascular access device (VAD) placement, and review VAD options. Journal articles, personal experience. A number of VAD options are available in clinical practice. Access planning should include comprehensive assessment, with attention to patient participation in the planning and selection process. Careful consideration should be given to long-term access needs and preservation of access sites. Oncology nurses are uniquely suited to perform a key role in VAD planning and placement. With knowledge of infusion therapy, anatomy and physiology, device options, and community resources, nurses can be key leaders in preserving vascular access and improving the safety and comfort of infusion therapy. Copyright 2010 Elsevier Inc. All rights reserved.

  19. Ample spectrum of vascular hepatic disease

    International Nuclear Information System (INIS)

    Camacho, Juan C; Marquez Adriana; Romero, Javier; Aguirre Diego

    2010-01-01

    Hepatic vascular diseases (HVD) are a broad spectrum of entities of low prevalence but with different clinical manifestations that may even lead to death. Its early detection and timely treatment may change the prognosis. Diagnostic imaging plays a key role and imaging findings may be typical. However, in most cases, radiologists must take into account a wide range of differential diagnosis. Computed tomography (CT) of the abdomen is one of the most useful tools for the diagnosis of HVD taking also into account the value of other imaging methods such as Doppler Ultrasound and Magnetic Resonance Imaging (MRI). HVD can be classified according to the compromised vascular structure and can be divided into venous, portal, arterial, sinusoidal and others disorders. The objective of this review is to describe the most common presentation HVD. The major imaging findings and differential diagnosis recognizing its correlation with the pathophysiological mechanisms.

  20. Cocoa, blood pressure, and vascular function.

    Science.gov (United States)

    Sudano, Isabella; Flammer, Andreas J; Roas, Susanne; Enseleit, Frank; Ruschitzka, Frank; Corti, Roberto; Noll, Georg

    2012-08-01

    The consumption of a high amount of fruits and vegetables was found to be associated with a lower risk of coronary heart disease and stroke. Epidemiologically, a similar relationship has been found with cocoa, a naturally polyphenol-rich food. Obviously, double blind randomized studies are difficult to perform with cocoa and chocolate, respectively. However, intervention studies strongly suggest that cocoa has several beneficial effects on cardiovascular health, including the lowering of blood pressure, the improvement of vascular function and glucose metabolism, and the reduction of platelet aggregation and adhesion. Several potential mechanisms through which cocoa might exert its positive effects have been proposed, among them activation of nitric oxide synthase, increased bioavailability of nitric oxide as well as antioxidant, and anti-inflammatory properties. It is the aim of this review to summarize the findings of cocoa and chocolate on blood pressure and vascular function.

  1. Vascularization of soft tissue engineering constructs

    DEFF Research Database (Denmark)

    Pimentel Carletto, Rodrigo

    nanotechnology-based paradigm for engineering vascularised liver tissue for transplantation”) and the Danish National Research Foundation and Villum Foundation’s Center for Intelligent Drug delivery and sensing Using microcontainers and Nanomechanics (Danish National Research Foundation (DNRF122).......Vascularization is recognized to be the biggest challenge for the fabrication of tissues and finally, organs in vitro. So far, several fabrication techniques have been proposed to create a perfusable vasculature within hydrogels, however, the vascularization and perfusion of hydrogels...... with mechanical properties in the range of soft tissues has not been fully achieved. My project focused on the fabrication and the active perfusion of hydrogel constructs with multi-dimensional vasculature and controlled mechanical properties targeting soft tissues. Specifically, the initial part of the research...

  2. Cocoa, Blood Pressure, and Vascular Function

    Directory of Open Access Journals (Sweden)

    Valeria Ludovici

    2017-08-01

    Full Text Available Cardiovascular disease (CVD represents the most common cause of death worldwide. The consumption of natural polyphenol-rich foods, and cocoa in particular, has been related to a reduced risk of CVD, including coronary heart disease and stroke. Intervention studies strongly suggest that cocoa exerts a beneficial impact on cardiovascular health, through the reduction of blood pressure (BP, improvement of vascular function, modulation of lipid and glucose metabolism, and reduction of platelet aggregation. These potentially beneficial effects have been shown in healthy subjects as well as in patients with risk factors (arterial hypertension, diabetes, and smoking or established CVD (coronary heart disease or heart failure. Several potential mechanisms are supposed to be responsible for the positive effect of cocoa; among them activation of nitric oxide (NO synthase, increased bioavailability of NO as well as antioxidant, and anti-inflammatory properties. It is the aim of this review to summarize the findings of cocoa and chocolate on BP and vascular function.

  3. Noninvasive studies of peripheral vascular disease

    International Nuclear Information System (INIS)

    Yao, J.S.T.

    1987-01-01

    Plethysmography probably is the oldest method for measuring blood flow. In this method, measurements are made of changes in volume of an organ or region of tissue. In the modern practice of vascular surgery, the use of plethysmography has been expanded to include detection of not only arterial occlusive disease but also carotid artery disease and venous problems. Several types of plethysmographs are now available for clinical use in the evaluation of arterial occlusions. These are volume, strain-gauge, and photoelectric plethysmographs. The water-filled volume recorder, popular in the early use of plethysmography, is now obsolete and has been replaced by the air-filled volume plethysmograph, notably, the pulse-volume recorder. For clinical application, the newer plethysmographs, such as the strain-gauge, photopletyhsmograph, and pulse-volume recorder, are now standard equipment in many vascular laboratories. They are discussed in this article

  4. Biophysical Regulation of Vascular Differentiation and Assembly

    CERN Document Server

    Gerecht, Sharon

    2011-01-01

    The ability to grow stem cells in the laboratory and to guide their maturation to functional cells allows us to study the underlying mechanisms that govern vasculature differentiation and assembly in health and disease. Accumulating evidence suggests that early stages of vascular growth are exquisitely tuned by biophysical cues from the microenvironment, yet the scientific understanding of such cellular environments is still in its infancy. Comprehending these processes sufficiently to manipulate them would pave the way to controlling blood vessel growth in therapeutic applications. This book assembles the works and views of experts from various disciplines to provide a unique perspective on how different aspects of its microenvironment regulate the differentiation and assembly of the vasculature. In particular, it describes recent efforts to exploit modern engineering techniques to study and manipulate various biophysical cues. Biophysical Regulation of Vascular Differentiation and Assembly provides an inter...

  5. Vascular endothelium receptors and transduction mechanisms

    CERN Document Server

    Gillis, C; Ryan, Una; Proceedings of the Advanced Studies Institute on "Vascular Endothelium: Receptors and Transduction Mechanisms"

    1989-01-01

    Beyond their obvious role of a barrier between blood and tissue, vascular endothelial cells are now firmly established as active and essential participants in a host of crucial physiological and pathophysiological functions. Probably the two most important factors responsible for promoting the current knowledge of endothelial functions are 1) observations in the late sixties-early seventies that many non-ventilatory properties of the lung could be attributed to the pulmonary endothelium and 2) the establishment, in the early and mid-seventies of procedures for routine culture of vascular endothelial cells. Many of these endothelial functions require the presence of receptors on the surface of the plasma membrane. There is now evidence for the existence among others of muscarinic, a-and /3-adrenergic, purine, insulin, histamine, bradykinin, lipoprotein, thrombin, paf, fibronectin, vitronectin, interleukin and albumin receptors. For some of these ligands, there is evidence only for the existence of endothelial ...

  6. Vascular anomalies of the cerebellopontine angle

    International Nuclear Information System (INIS)

    Papanagiotou, P.; Grunwald, I.Q.; Politi, M.; Struffert, T.; Ahlhelm, F.; Reith, W.

    2006-01-01

    Vascular anomalies of the cerebellopontine angle are rare compared to tumors in this area. Irritation of the trigeminal, facial, or vestibulocochlear nerve may cause trigeminal neuralgia, hemifacial spasm and vertigo, or tinnitus accordingly. Vessel loops in the cerebellopontine cisterns may cause compression at the root entry or exit zone of the cranial nerves V, VII, and VIII, a phenomenon which is called ''vascular loop syndrome.'' Megadolichobasilar artery and aneurysms of the vertebrobasilar system can also lead to dislocation and compression of the cranial nerves and brain stem. Three-dimensional CISS MR imaging and MR angiography are useful in the detection of neurovascular compression. Microvascular decompression is an effective surgical procedure in the management of compression syndromes of the cranial nerves V, VII, and VIII. (orig.) [de

  7. Molecular parallels between neural and vascular development.

    Science.gov (United States)

    Eichmann, Anne; Thomas, Jean-Léon

    2013-01-01

    The human central nervous system (CNS) features a network of ~400 miles of blood vessels that receives >20% of the body's cardiac output and uses most of its blood glucose. Many human diseases, including stroke, retinopathy, and cancer, are associated with the biology of CNS blood vessels. These vessels originate from extrinsic cell populations, including endothelial cells and pericytes that colonize the CNS and interact with glia and neurons to establish the blood-brain barrier and control cerebrovascular exchanges. Neurovascular interactions also play important roles in adult neurogenic niches, which harbor a unique population of neural stem cells that are intimately associated with blood vessels. We here review the cellular and molecular mechanisms required to establish the CNS vascular network, with a special focus on neurovascular interactions and the functions of vascular endothelial growth factors.

  8. Treatment of hemobilia by transcatheter vascular occlusion

    International Nuclear Information System (INIS)

    Vaughan, R.; Roesch, J.; Keller, F.S.; Antonovic, R.; Veterans Administration Medical Center, Portland, OR

    1984-01-01

    Four cases of hemobilia treated by transcatheter arterial occlusion are presented and reviewed with 30 similar cases reported in the literature. Transcatheter vascular occlusion successfully controlled hemorrhage in all 34 patients. No obvious liver parenchymal damage appeared in 26 patients; transient elevation of liver enzymes occurred in 6 patients (18%) including one in our series; two of the patients reviewed died of acute hepatic insufficiency following nonselective hepatic artery embolization. Hemobilia should be considered when gastrointestinal hemorrhage occurs after abdominal trauma, liver biopsy or other manipulative liver procedures. Hepatic angiography establishes the diagnosis and selective vascular occlusion is the treatment of choice for control of intractable or recurrent hemorrhage. Techniques and precautions for the diagnosis and transcatheter therapy of hemobilia are discussed. (orig.)

  9. Prediction of Major Vascular Events after Stroke

    DEFF Research Database (Denmark)

    Ovbiagele, Bruce; Goldstein, Larry B.; Amarenco, Pierre

    2014-01-01

    BACKGROUND: Identifying patients with recent stroke or transient ischemic attack (TIA) at high risk of major vascular events (MVEs; stroke, myocardial infarction, or vascular death) may help optimize the intensity of secondary preventive interventions. We evaluated the relationships between...... the baseline Framingham Coronary Risk Score (FCRS) and a novel risk prediction model and with the occurrence of MVEs after stroke or TIA in subjects enrolled in the Stroke Prevention by Aggressive Reduction in Cholesterol Level (SPARCL) trial. METHODS: Data from the 4731 subjects enrolled in the SPARCL study...... were analyzed. Hazard ratios (HRs) from Cox regression models were used to determine the risk of subsequent MVEs based on the FCRS predicting 20% or more 10-year coronary heart disease risk. The novel risk model was derived based on multivariable modeling with backward selection. Model discrimination...

  10. Vascular lesions of the vocal fold.

    Science.gov (United States)

    Gökcan, Kürşat Mustafa; Dursun, Gürsel

    2009-04-01

    The aim of the study was to present symptoms, laryngological findings, clinical course, management modalities, and consequences of vascular lesions of vocal fold. This study examined 162 patients, the majority professional voice users, with vascular lesions regarding their presenting symptoms, laryngological findings, clinical courses and treatment results. The most common complaint was sudden hoarseness with hemorrhagic polyp. Microlaryngoscopic surgery was performed in 108 cases and the main indication of surgery was the presence of vocal fold mass or development of vocal polyp during clinical course. Cold microsurgery was utilized for removal of vocal fold masses and feeding vessels cauterized using low power, pulsed CO(2) laser. Acoustic analysis of patients revealed a significant improvement of jitter, shimmer and harmonics/noise ratio values after treatment. Depending on our clinical findings, we propose treatment algorithm where voice rest and behavioral therapy is the integral part and indications of surgery are individualized for each patient.

  11. Protein Kinase C Inhibitors as Modulators of Vascular Function and Their Application in Vascular Disease

    Directory of Open Access Journals (Sweden)

    Raouf A. Khalil

    2013-03-01

    Full Text Available Blood pressure (BP is regulated by multiple neuronal, hormonal, renal and vascular control mechanisms. Changes in signaling mechanisms in the endothelium, vascular smooth muscle (VSM and extracellular matrix cause alterations in vascular tone and blood vessel remodeling and may lead to persistent increases in vascular resistance and hypertension (HTN. In VSM, activation of surface receptors by vasoconstrictor stimuli causes an increase in intracellular free Ca2+ concentration ([Ca2+]i, which forms a complex with calmodulin, activates myosin light chain (MLC kinase and leads to MLC phosphorylation, actin-myosin interaction and VSM contraction. Vasoconstrictor agonists could also increase the production of diacylglycerol which activates protein kinase C (PKC. PKC is a family of Ca2+-dependent and Ca2+-independent isozymes that have different distributions in various blood vessels, and undergo translocation from the cytosol to the plasma membrane, cytoskeleton or the nucleus during cell activation. In VSM, PKC translocation to the cell surface may trigger a cascade of biochemical events leading to activation of mitogen-activated protein kinase (MAPK and MAPK kinase (MEK, a pathway that ultimately increases the myofilament force sensitivity to [Ca2+]i, and enhances actin-myosin interaction and VSM contraction. PKC translocation to the nucleus may induce transactivation of various genes and promote VSM growth and proliferation. PKC could also affect endothelium-derived relaxing and contracting factors as well as matrix metalloproteinases (MMPs in the extracellular matrix further affecting vascular reactivity and remodeling. In addition to vasoactive factors, reactive oxygen species, inflammatory cytokines and other metabolic factors could affect PKC activity. Increased PKC expression and activity have been observed in vascular disease and in certain forms of experimental and human HTN. Targeting of vascular PKC using PKC inhibitors may function in

  12. Improved vascularization of planar membrane diffusion devices following continuous infusion of vascular endothelial growth factor.

    Science.gov (United States)

    Trivedi, N; Steil, G M; Colton, C K; Bonner-Weir, S; Weir, G C

    2000-01-01

    Improving blood vessel formation around an immunobarrier device should improve the survival of the encapsulated tissue. In the present study we investigated the formation of new blood vessels around a planar membrane diffusion device (the Baxter Theracyte System) undergoing a continuous infusion of vascular endothelial growth factor through the membranes and into the surrounding tissue. Each device (20 microl) had both an inner immunoisolation membrane and an outer vascularizing membrane. Human recombinant vascular endothelial growth factor-165 was infused at 100 ng/day (low dose: n = 6) and 500 ng/day (high dose: n = 7) for 10 days into devices implanted s.c. in Sprague-Dawley rats; noninfused devices transplanted for an identical period were used as controls (n = 5). Two days following the termination of VEGF infusion, devices were loaded with 20 microl of Lispro insulin (1 U/kg) and the kinetics of insulin release from the lumen of the device was assessed. Devices were then explanted and the number of blood vessels (capillary and noncapillary) was quantified using morphometry. High-dose vascular endothelial growth factor infusion resulted in two- to threefold more blood vessels around the device than that obtained with the noninfused devices and devices infused with low-dose vascular endothelial growth factor. This increase in the number of blood vessels was accompanied by a modest increase in insulin diffusion from the device in the high-dose vascular endothelial growth factor infusion group. We conclude that vascular endothelial growth factor can be used to improve blood vessel formation adjacent to planar membrane diffusion devices.

  13. NF1 Signal Transduction and Vascular Dysfunction

    Science.gov (United States)

    2015-05-01

    microenvironment that promotes much of the pathology associated with the disease . Moreover we hypothesize that a mechanistic consequence of the loss...obliteration of the normal red pulp architecture. In addition, we found significant peri-aveolar and peri-vascular inflammatory infiltrates in the lung...the mouse model of NF1 disease in the endothelium we proposed and have done experiments investigating the loss of endothelial NF1 in the adult

  14. Role of endovascular treatment in vascular injuries

    International Nuclear Information System (INIS)

    Tahir, M.M.; Haq, T.U.

    2012-01-01

    Objective: To evaluate retrospectively the results, complications and follow-up of patients after endovascular treatment of vascular injuries. Methods: Fifty transcatheter embolisation procedures (TCE) were performed in 46 patients between 1999 and 2008 at the Aga Khan University Hospital, Karachi. Injuries in 14 (30.4%) patients were due to road traffic accident; iatrogenic in 13 (28%); accidental in 6 (13%). Firearms, bomb blasts and earthquake contributed to injuries in 8(17%), 4(8.8%) and 1(2.2%) patients respectively. All patients underwent angiography and had evidence of either active haemorrhage, pseudo-aneurysm, abnormal vascularity or arteriovenous fistula. Follow-up ranged from 1 day to 6 years with mean of 10.5 months. Medical record files, lab results and imaging reports were utilised for the study. Procedure was declared as technically successful when there was cessation of extravasation, occlusion of fistula or exclusion of pseudo-aneurysm in the post-embolisation angiograms. Treatment was deemed clinically successful if there was resolution of the indication for which the procedure was done. Results: Transcatheter embolisation was technically successful in occluding vascular lesions in all 46 (100%) patients. Lesions recurred in 4 (9%) patients who underwent initially successful TCE. These patients were treated effectively with repeated TCE. Three patients died during the same hospital stay and 3 patients died after being discharged from the hospital. All these patients were treated successfully with TCE and had factors other then TCE contributing to their mortality. Conclusion: Transcatheter embolisation for vascular injuries was found to be a satisfactory procedure, with low morbidity and mortality rates. (author)

  15. Vascular access: the impact of ultrasonography

    Science.gov (United States)

    de Almeida, Carlos Eduardo Saldanha

    2016-01-01

    ABSTRACT Vascular punctures are often necessary in critically ill patients. They are secure, but not free of complications. Ultrasonography enhances safety of the procedure by decreasing puncture attempts, complications and costs. This study reviews important publications and the puncture technique using ultrasound, bringing part of the experience of the intensive care unit of the Hospital Israelita Albert Einstein, São Paulo (SP), Brazil, and discussing issues that should be considered in future studies. PMID:28076607

  16. Vascular Dysfunction in Horses with Endocrinopathic Laminitis.

    Directory of Open Access Journals (Sweden)

    Ruth A Morgan

    Full Text Available Endocrinopathic laminitis (EL is a vascular condition of the equine hoof resulting in severe lameness with both welfare and economic implications. EL occurs in association with equine metabolic syndrome and equine Cushing's disease. Vascular dysfunction, most commonly due to endothelial dysfunction, is associated with cardiovascular risk in people with metabolic syndrome and Cushing's syndrome. We tested the hypothesis that horses with EL have vascular, specifically endothelial, dysfunction. Healthy horses (n = 6 and horses with EL (n = 6 destined for euthanasia were recruited. We studied vessels from the hooves (laminar artery, laminar vein and the facial skin (facial skin arteries by small vessel wire myography. The response to vasoconstrictors phenylephrine (10-9-10-5M and 5-hydroxytryptamine (5HT; 10-9-10-5M and the vasodilator acetylcholine (10-9-10-5M was determined. In comparison with healthy controls, acetylcholine-induced relaxation was dramatically reduced in all intact vessels from horses with EL (% relaxation of healthy laminar arteries 323.5 ± 94.1% v EL 90.8 ± 4.4%, P = 0.01, laminar veins 129.4 ± 14.8% v EL 71.2 ± 4.1%, P = 0.005 and facial skin arteries 182.0 ± 40.7% v EL 91.4 ± 4.5%, P = 0.01. In addition, contractile responses to phenylephrine and 5HT were increased in intact laminar veins from horses with EL compared with healthy horses; these differences were endothelium-independent. Sensitivity to phenylephrine was reduced in intact laminar arteries (P = 0.006 and veins (P = 0.009 from horses with EL. Horses with EL exhibit significant vascular dysfunction in laminar vessels and in facial skin arteries. The systemic nature of the abnormalities suggest this dysfunction is associated with the underlying endocrinopathy and not local changes to the hoof.

  17. Role of vascular physiology in hyperthermia

    International Nuclear Information System (INIS)

    Song, C.W.

    1987-01-01

    The rate of blood supply to tumors significantly varies depending on the tumor type, site of tumor growth, and the stage of tumor growth. Even in the same tumor, blood flow is rather heterogeneous. The peripheral area of the tumors where the tissue pressure is relatively low is usually well perfused. Blood flow in the tumors may or may not be greater than that in the adjacent normal tissues. The response of newly formed tumor blood vessels to external stress, such as heat, it different from that in the normal tissues. Blood flow in the experimental rodent tumors initially increases up to twofold of control when heated at relatively low temperatures but tends to decrease when heated at temperatures above 42 0 -43 0 C. On the contrary, blood flow in the skin and muscle of rodents increases up to 20-fold before vascular damage occurs on heating at 43 0 -45 0 C. It thus appears that the vascular beds in tumors are more vulnerable to heat than those in normal tissues. Because of the large increase in blood flow in normal tissue on heating, heat dissipation by blood flow is usually greater in normal tissues than that in tumors during heating. Consequently, the temperature of tumors may rise higher than that in normal tissues. Preferential heating of tumors, however, may not be achieved all the time because the relative blood perfusion in some tumors or in parts of a tumor remains greater than that in the surrounding normal tissues. The intrinsically acidic intratumor environment becomes further acidic on heating owing to an increase in the synthesis of acidic metabolites and retarded removal of them as a result of heat-induced vascular damage. The intratumor environment also becomes hypoxic as a result of retardation of blood flow and vascular damage after heating

  18. Analgesics and sedatives in vascular interventionist radiologic

    International Nuclear Information System (INIS)

    Gregorio, M.A. de; Opta, J.M.; Pulido, J.M.; Encarnacion, C.E.; Arino, I., Fernandez, J.A.; Alfonso, E.R.

    1993-01-01

    Interventionist radiology routinely requires the use of different drugs (analgesics and sedatives) in the course of a procedure. Aside from their therapeutic action, these drugs can produce secondary or undesirable effects, making necessary an in-depth knowledge of them to assure their safe and efficient management. The aim of this work is to provide the vascular interventionist radiologist with additional information on the management of those drugs that contribute to minimizing patient discomfort and pain in interventionist procedures. Author

  19. Robotic vascular resections during Whipple procedure

    OpenAIRE

    Allan, Bassan J.; Novak, Stephanie M.; Hogg, Melissa E.; Zeh, Herbert J.

    2018-01-01

    Indications for resection of pancreatic cancers have evolved to include selected patients with involvement of peri-pancreatic vascular structures. Open Whipple procedures have been the standard approach for patients requiring reconstruction of the portal vein (PV) or superior mesenteric vein (SMV). Recently, high-volume centers are performing minimally invasive Whipple procedures with portovenous resections. Our institution has performed seventy robotic Whipple procedures with concomitant vas...

  20. Endothelial microparticles: Sophisticated vesicles modulating vascular function

    Science.gov (United States)

    Curtis, Anne M; Edelberg, Jay; Jonas, Rebecca; Rogers, Wade T; Moore, Jonni S; Syed, Wajihuddin; Mohler, Emile R

    2015-01-01

    Endothelial microparticles (EMPs) belong to a family of extracellular vesicles that are dynamic, mobile, biological effectors capable of mediating vascular physiology and function. The release of EMPs can impart autocrine and paracrine effects on target cells through surface interaction, cellular fusion, and, possibly, the delivery of intra-vesicular cargo. A greater understanding of the formation, composition, and function of EMPs will broaden our understanding of endothelial communication and may expose new pathways amenable for therapeutic manipulation. PMID:23892447

  1. New molecular probes of vascular inflammation

    International Nuclear Information System (INIS)

    Molecular Cardiovascular Imaging, Westfälische Wilhelms University Münster, Münster, (Germany))" data-affiliation=" (Department of Nuclear Medicine, University Hospital Münster, Münster, and DFG CRC 656 Molecular Cardiovascular Imaging, Westfälische Wilhelms University Münster, Münster, (Germany))" >VRACHIMIS, Alexis; HONOLD, Lisa; Cells in Motion Cluster of Excellence, Westfälische Wilhelms University Münster, Münster, (Germany))" data-affiliation=" (European Institute of Molecular Imaging, Westfälische Wilhelms University Münster, Münster, and DFG EXC 1003 Cells in Motion Cluster of Excellence, Westfälische Wilhelms University Münster, Münster, (Germany))" >FAUST, Andreas; Cells in Motion Cluster of Excellence, Westfälische Wilhelms University Münster, Münster, (Germany))" data-affiliation=" (European Institute of Molecular Imaging, Westfälische Wilhelms University Münster, Münster, and DFG EXC 1003 Cells in Motion Cluster of Excellence, Westfälische Wilhelms University Münster, Münster, (Germany))" >HERMANN, Sven; SCHÄFERS, Michael

    2016-01-01

    New molecular imaging approaches featuring the assessment of inflammatory processes in the vascular wall on top of existing anatomic and functional vessel imaging procedures could emerge as decisive tools for the understanding and prevention of cardiovascular events. In this respect imaging approaches addressing specific molecular and cellular targets in atherosclerosis are of high interest. This review summarizes the rationale and current status of nuclear imaging probes which possess high translational potential.

  2. Blood flow measurements during hemodialysis vascular access interventions - Catheter-based thermodilution or Doppler ultrasound?

    DEFF Research Database (Denmark)

    Heerwagen, Søren T; Hansen, Marc A; Schroeder, Torben V

    2012-01-01

    by ultrasound dilution was determined within three days of the procedure. The methods were compared using regression analysis and tested for systematic bias. Results: Failure to position the thermodilutional catheter correctly was observed in 8 out of 46 (17%) pre-intervention measurements. Post-intervention......Purpose: To test the clinical performance of catheter-based thermodilution and Doppler ultrasound of the feeding brachial artery for blood flow measurements during hemodialysis vascular access interventions.Methods: Thirty patients with arteriovenous fistulas who underwent 46 interventions had...

  3. Severe Juxtahepatic Venous Injury: Survival after Prolonged Hepatic Vascular Isolation Without Shunting

    Directory of Open Access Journals (Sweden)

    J. E. J. Krige

    1990-01-01

    Full Text Available Survival following major juxtahepatic venous injury is rare in blunt liver trauma despite the use of intracaval shunting. Prolonged liver arterial inflow control, total hepatic venous isolation and lobectomy without shunting was used in a patient to repair a combined vena caval and hepatic venous injury after blunt liver injury. An extended period of normothermic hepatic ischemia was tolerated. Early recognition of retrohepatic venous injury and temporary liver packing to control bleeding and correct hypovolemia are essential before caval occlusion. Hepatic vascular isolation without shunting is an effective simple alternative technique allowing major venous repair in complex liver trauma.

  4. Incisive canal deflation for correct implant placement: case report.

    Science.gov (United States)

    Spin-Neto, Rubens; Bedran, Telma Blanca Lombardo; de Paula, Wagner Nunes; de Freitas, Rubens Moreno; de Oliveira Ramalho, Lizeti Toledo; Marcantonio, Elcio

    2009-12-01

    This article is a case report of a patient in whom the prosthetic planning indicated the necessity of an incisive canal deflation for the correct installation of an implant that is to be osseointegrated. In the reopening phase after the bone graft installation, the incisive canal deflation (biopsy of its content) was done and titanium implants were installed with one of them invading the anatomical space occupied previously by the incisive canal. The biopsy analysis showed fragments of the incisive artery and nerve, which are responsible for the anterior upper-tooth pulp, the periodontium vascularization and the innervation. From the anastomosis present along with other structures allied with the absence of teeth in the region, there was no detriment to the patient caused by the deflation. Incisive canal deflation is a viable technique in implantology. It can permit ideal prosthetic planning with no detriment to the patient.

  5. Achados de imagem e alternativas terapêuticas das malformações vasculares periféricas Imaging findings and therapeutic alternatives for peripheral vascular malformations

    Directory of Open Access Journals (Sweden)

    Lucas Moretti Monsignore

    2010-06-01

    Full Text Available As malformações vasculares periféricas compreendem um espectro de lesões que se tornam aparentes no decorrer da vida e podem ser encontradas em praticamente todo o corpo. São pouco comuns e frequentemente confundidas com o hemangioma infantil. Estas doenças são completamente distintas tanto em relação à história clínica como ao prognóstico e às formas de tratamento. Nestas lesões, a história evolutiva e as características do exame físico são de extrema importância para o adequado diagnóstico clinicorradiológico, que guiará a melhor alternativa terapêutica. As classificações mais recentes dividem as malformações vasculares periféricas levando em consideração o fluxo sanguíneo (alto e baixo e os componentes vasculares envolvidos (arteriais, capilares, linfáticos e venosos. As malformações vasculares periféricas representam um desafio diagnóstico e terapêutico, e exames complementares como tomografia computadorizada, ultrassonografia com Doppler e ressonância magnética, em conjunto com a história clínica, podem trazer informações quanto às características de fluxo e à extensão das lesões. Arteriografia e flebografia confirmam o diagnóstico, avaliam a sua extensão e orientam a decisão terapêutica. Malformações de baixo fluxo geralmente são tratadas por abordagem percutânea e injeção de agente esclerosante, enquanto para as malformações de alto fluxo o acesso é endovascular com uso de agentes embolizantes permanentes líquidos ou sólidos.Peripheral vascular malformations represent a spectrum of lesions that appear through the lifetime and can be found in the whole body. Such lesions are uncommon and are frequently confounded with infantile hemangioma, a common benign neoplastic lesion. In the presence of such lesions, the correlation between the clinical and radiological findings is extremely important to achieve a correct diagnosis, which will guide the best therapeutic approach. The

  6. Early Vascular Ageing - A Concept in Development.

    Science.gov (United States)

    M Nilsson, Peter

    2015-04-01

    Cardiovascular disease (CVD) is a prevalent condition in the elderly, often associated with metabolic disturbance and type 2 diabetes. For a number of years, research dedicated to understand atherosclerosis dominated, and for many good reasons, this pathophysiological process being proximal to the CVD events. In recent years, research has been devoted to an earlier stage of vascular pathology named arteriosclerosis (arterial stiffness) and the new concept of early vascular ageing (EVA), developed by a group of mostly European researchers. This overview describes recent developments in research dedicated to EVA and new emerging aspects found in studies of families at high cardiovascular risk. There are new aspects related to genetics, telomere biology and the role of gut microbiota. However, there is still no unifying definition available of EVA and no direct treatment, but rather only recommendations for conventional cardiovascular risk factor control. New interventions are being developed - not only new antihypertensive drugs, but also new drugs for vascular protection - the selective angiotensin-II (AT2) agonist Compound 21 (C21). Human studies are eagerly awaited. Even new functional food products could have the potential to positively influence cardiometabolic regulation, to be confirmed.

  7. Altos custos financeiros do trauma vascular

    Directory of Open Access Journals (Sweden)

    Ricardo Costa-Val

    Full Text Available OBJETIVO: Demonstrar o custo e impacto financeiro referente à primeira abordagem cirúrgica das lesões vasculares em pacientes admitidos no Hospital João XXIII/FHEMIG, entre os anos de 2004 a 2006. MéTODOS: Trata-se de um estudo com aprovação ética, retrospectivo, de coorte e descritivo realizado a partir da auditoria de contas hospitalares referentes a 70 prontuários catalogados pelo Serviço de Trauma Cardiovascular. RESULTADOS: Cinco (7,14% prontuários foram excluídos por má qualidade técnica. O valor monetário repassado pelo Sistema Único de Saúde e pelo setor privado foram de R$ 103.614,96 (US$ 60.949,97 e de R$ 185.888,21 (US$ 109.346,0, respectivamente, implicando em defasagem potencial de 44%. Houve correlação direta entre custos e topografia anatômica das lesões e exponencial em relação às variáveis hemoderivados e próteses vasculares. CONCLUSÃO: Este estudo corrobora os altos custos do trauma vascular e fortalece a importância da auditoria de contas para as tomadas de decisões médicas.

  8. Pancreatic transplantation: Radiologic evaluation of vascular complications

    International Nuclear Information System (INIS)

    Snider, J.F.; Hunter, D.W.; Kuni, C.C.; Castaneda-Zuniga, W.R.; Letourneau, J.G.

    1991-01-01

    Transplantation of the pancreas is an increasingly common therapeutic option for preventing or delaying complications of type I diabetes mellitus. The authors studied the relative roles of various radiologic examinations in diagnosing vascular complications in these grafts including arterial and venous thrombosis, stenosis, and anastomotic leak (the most common vascular factors that necessitate pancreatectomy of the transplant), as defined with pathologic or arteriographic data. The results of 78 scintigraphic flow studies, 40 abdominal and pelvic computed tomographic (CT) scans, 27 sonograms, and eight color Doppler studies were evaluated in 52 patients who received a total of 27 cadaveric and 26 living-donor grafts over a 12-year period. These results were correlated with the data from 45 gross and microscopic pathologic studies and 37 arteriograms to determine their relative value in enabling detection of graft thrombosis and other vascular complications. Scintigraphy, CT, sonography, and color Doppler were all sensitive in detection of generalized graft abnormalities but lacked specificity in defining the underlying etiologic factors

  9. Pancreatic transplantation: Radiologic evaluation of vascular complications

    Energy Technology Data Exchange (ETDEWEB)

    Snider, J.F.; Hunter, D.W.; Kuni, C.C.; Castaneda-Zuniga, W.R.; Letourneau, J.G. (Univ. of Minnesota Hospital and Clinic, Minneapolis (USA))

    1991-03-01

    Transplantation of the pancreas is an increasingly common therapeutic option for preventing or delaying complications of type I diabetes mellitus. The authors studied the relative roles of various radiologic examinations in diagnosing vascular complications in these grafts including arterial and venous thrombosis, stenosis, and anastomotic leak (the most common vascular factors that necessitate pancreatectomy of the transplant), as defined with pathologic or arteriographic data. The results of 78 scintigraphic flow studies, 40 abdominal and pelvic computed tomographic (CT) scans, 27 sonograms, and eight color Doppler studies were evaluated in 52 patients who received a total of 27 cadaveric and 26 living-donor grafts over a 12-year period. These results were correlated with the data from 45 gross and microscopic pathologic studies and 37 arteriograms to determine their relative value in enabling detection of graft thrombosis and other vascular complications. Scintigraphy, CT, sonography, and color Doppler were all sensitive in detection of generalized graft abnormalities but lacked specificity in defining the underlying etiologic factors.

  10. Arterial vascularization of the pineal gland.

    Science.gov (United States)

    Kahilogullari, Gokmen; Ugur, Hasan Caglar; Comert, Ayhan; Brohi, Recep Ali; Ozgural, Onur; Ozdemir, Mevci; Karahan, Suleyman Tuna

    2013-10-01

    The arterial vascularization of the pineal gland (PG) remains a debatable subject. This study aims to provide detailed information about the arterial vascularization of the PG. Thirty adult human brains were obtained from routine autopsies. Cerebral arteries were separately cannulated and injected with colored latex. The dissections were carried out using a surgical microscope. The diameters of the branches supplying the PG at their origin and vascularization areas of the branches of the arteries were investigated. The main artery of the PG was the lateral pineal artery, and it originated from the posterior circulation. The other arteries included the medial pineal artery from the posterior circulation and the rostral pineal artery mainly from the anterior circulation. Posteromedial choroidal artery was an important artery that branched to the PG. The arterial supply to the PG was studied comprehensively considering the debate and inadequacy of previously published studies on this issue available in the literature. This anatomical knowledge may be helpful for surgical treatment of pathologies of the PG, especially in children who develop more pathology in this region than adults.

  11. VASCULAR REMODELING IN HYPERTENSION: ANGIOGENESIS FEATURES

    Directory of Open Access Journals (Sweden)

    L. A. Haisheva

    2014-07-01

    Full Text Available Aim — cross-sectional study of changes in various segments of the vascular bed in arterial hypertension (AH, defining the role of inducers and inhibitors of angiogenesis in these processes.Materials and methods. The study included 99 patients with arterial hypertension of I–II degree, average age of 63.2 ± 2.6 years, diseaseduration 9.2 ± 7.2 years.Results. It was found that patients with arterial hypertension have disorders in all segments of vascular bed: endothelial dysfunction (highvWF, microcirculatory disorders, and increased pulse wave velocity (PWV of elastic-type vessels. The level of angioginesis factors doesnot depend on such parameters as gender, age, body mass index. Smoking and duration of hypertension influence on vascular endothelialgrowth factor raise and endostatin levels are higher in patients with family history of cardiovascular diseases. Duration of disease is directlycorrelated with microcirculatory disorders and the PWV, correlation between microcirculatory disorders and pulse wave velocity indicatetheir common processes.

  12. Amplatzer vascular plugs in congenital cardiovascular malformations

    International Nuclear Information System (INIS)

    Barwad, Parag; Ramakrishnan, Sivasubramanian; Kothari, Shyam S; Saxena, Anita; Gupta, Saurabh K; Juneja, Rajnish; Gulati, Gurpreet Singh; Jagia, Priya; Sharma, Sanjiv

    2013-01-01

    Amplatzer vascular plugs (AVPs) are devices ideally suited to close medium-to-large vascular communications. There is limited published literature regarding the utility of AVPs in congenital cardiovascular malformations (CCVMs). To describe the use of AVPs in different CCVMs and to evaluate their safety and efficacy. All patients who required an AVP for the closure of CCVM were included in this retrospective review of our catheterization laboratory data. The efficacy and safety of AVPs are reported. A total of 39 AVPs were implanted in 31 patients. Thirteen (33%) were AVP type I and 23 (59%) were AVP type II. AVP type III were implanted in two patients and type IV in one patient. The major indications for their use included closure of pulmonary arteriovenous malformation (AVM) (n = 7), aortopulmonary collaterals (n = 7), closure of a patent Blalock-Taussig shunt (n = 5), systemic AVM (n = 5), coronary AVM (n = 4), patent ductus arteriosus (PDA) (n = 3), pulmonary artery aneurysms (n = 3), and venovenous collaterals (n = 2). Deployment of the AVP was done predominantly via the 5 – 7F Judkin's right coronary guide catheter. Overall 92% of the AVPs could be successfully deployed and resulted in occlusion of the target vessel in all cases, within 10 minutes. No procedure-related or access site complication occurred. AVPs are versatile, easy to use, and effective devices to occlude the vascular communications in a variety of settings. AVP II is especially useful in the closure of tubular structures with a high flow

  13. Vascular development in the vertebrate pancreas

    Science.gov (United States)

    Azizoglu, D. Berfin; Chong, Diana C.; Villasenor, Alethia; Magenheim, Judith; Barry, David M.; Lee, Simon; Marty-Santos, Leilani; Fu, Stephen; Dor, Yuval; Cleaver, Ondine

    2016-01-01

    The vertebrate pancreas is comprised of a highly branched tubular epithelium, which is intimately associated with an extensive and specialized vasculature. While we know a great deal about basic vascular anatomy of the adult pancreas, as well as islet capillaries, surprisingly little is known about the ontogeny of its blood vessels. Here, we analyze development of the pancreatic vasculature in the mouse embryo. We show that pancreatic epithelial branches intercalate with the fine capillary plexus of the surrounding pancreatic mesenchyme. Endothelial cells (ECs) within this mesenchyme are heterogeneous from the onset of organogenesis. Pancreatic arteries take shape before veins, in a manner analogous to early embryonic vessels. The main central artery forms during mid-gestation, as a result of vessel coalescence and remodeling of a vascular plexus. In addition, we show that vessels in the forming pancreas display a predictable architecture that is dependent on VEGF signaling. Over-expression of VEGF disrupts vascular patterning and arteriovenous differentiation within the developing pancreas. This study constitutes a first-time cellular and molecular characterization of pancreatic blood vessels, as they coordinately grow along with the pancreatic epithelium. PMID:27789228

  14. Vascularized nerve grafts: an experimental study.

    Science.gov (United States)

    Donzelli, Renato; Capone, Crescenzo; Sgulò, Francesco Giovanni; Mariniello, Giuseppe; Maiuri, Francesco

    2016-08-01

    The aim of this study is to define an experimental model in order to promote the functional recovery of the nerves using grafts with vascular support (Vascular Nerve Grafts - VNG). The aim of this study is to define, on an experimental model in normal recipient bed, whether the functional recovery with VNG is superior to that obtained non-vascularized graft (NNG). Twenty male rabbits, which underwent dissection of sciatic nerve, were later treated by reinnervation through an autograft. In 10 animals the reconstruction of sciatic nerve was realized with VNG; in 10 control animals the reconstruction of sciatic nerve was realized with NNG. The VNG group showed a better axonal organization and a significantly higher number of regenerated axons in the early phases (after 30 days) than the NNG group, whereas the difference in the axonal number at day 90 was less significant; besides, the axon diameter and the myelin thickness were not significantly improved by VNG group. Our data suggests that the use of VNG leads to a faster regeneration process and a better functional recovery, although the final results are comparable to those of the NNG. VNG improve the quality of the axonal regeneration (axonal diameter and Schwann cells), although the increase in the axonal number is not significant and does not improve the long-term functional outcome.

  15. Vascular nitric oxide: Beyond eNOS

    Directory of Open Access Journals (Sweden)

    Yingzi Zhao

    2015-10-01

    Full Text Available As the first discovered gaseous signaling molecule, nitric oxide (NO affects a number of cellular processes, including those involving vascular cells. This brief review summarizes the contribution of NO to the regulation of vascular tone and its sources in the blood vessel wall. NO regulates the degree of contraction of vascular smooth muscle cells mainly by stimulating soluble guanylyl cyclase (sGC to produce cyclic guanosine monophosphate (cGMP, although cGMP-independent signaling [S-nitrosylation of target proteins, activation of sarco/endoplasmic reticulum calcium ATPase (SERCA or production of cyclic inosine monophosphate (cIMP] also can be involved. In the blood vessel wall, NO is produced mainly from l-arginine by the enzyme endothelial nitric oxide synthase (eNOS but it can also be released non-enzymatically from S-nitrosothiols or from nitrate/nitrite. Dysfunction in the production and/or the bioavailability of NO characterizes endothelial dysfunction, which is associated with cardiovascular diseases such as hypertension and atherosclerosis.

  16. Vascular development in the vertebrate pancreas.

    Science.gov (United States)

    Azizoglu, D Berfin; Chong, Diana C; Villasenor, Alethia; Magenheim, Judith; Barry, David M; Lee, Simon; Marty-Santos, Leilani; Fu, Stephen; Dor, Yuval; Cleaver, Ondine

    2016-12-01

    The vertebrate pancreas is comprised of a highly branched tubular epithelium, which is intimately associated with an extensive and specialized vasculature. While we know a great deal about basic vascular anatomy of the adult pancreas, as well as islet capillaries, surprisingly little is known about the ontogeny of its blood vessels. Here, we analyze development of the pancreatic vasculature in the mouse embryo. We show that pancreatic epithelial branches intercalate with the fine capillary plexus of the surrounding pancreatic mesenchyme. Endothelial cells (ECs) within this mesenchyme are heterogeneous from the onset of organogenesis. Pancreatic arteries take shape before veins, in a manner analogous to early embryonic vessels. The main central artery forms during mid-gestation, as a result of vessel coalescence and remodeling of a vascular plexus. In addition, we show that vessels in the forming pancreas display a predictable architecture that is dependent on VEGF signaling. Over-expression of VEGF disrupts vascular patterning and arteriovenous differentiation within the developing pancreas. This study constitutes a first-time in-depth cellular and molecular characterization of pancreatic blood vessels, as they coordinately grow along with the pancreatic epithelium. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Electrotonic vascular signal conduction and nephron synchronization

    DEFF Research Database (Denmark)

    Marsh, D.J.; Toma, I.; Sosnovtseva, Olga

    2009-01-01

    Marsh DJ, Toma I, Sosnovtseva OV, Peti-Peterdi J, Holstein-Rathlou NH. Electrotonic vascular signal conduction and nephron synchronization. Am J Physiol Renal Physiol 296: F751-F761, 2009. First published December 30, 2008; doi:10.1152/ajprenal.90669.2008.-Tubuloglomerular feedback (TGF) and the ......Marsh DJ, Toma I, Sosnovtseva OV, Peti-Peterdi J, Holstein-Rathlou NH. Electrotonic vascular signal conduction and nephron synchronization. Am J Physiol Renal Physiol 296: F751-F761, 2009. First published December 30, 2008; doi:10.1152/ajprenal.90669.2008.-Tubuloglomerular feedback (TGF......) and the myogenic mechanism control afferent arteriolar diameter in each nephron and regulate blood flow. Both mechanisms generate self-sustained oscillations, the oscillations interact, TGF modulates the frequency and amplitude of the myogenic oscillation, and the oscillations synchronize; a 5: 1 frequency ratio...... is the most frequent. TGF oscillations synchronize in nephron pairs supplied from a common cortical radial artery, as do myogenic oscillations. We propose that electrotonic vascular signal propagation from one juxtaglomerular apparatus interacts with similar signals from other nephrons to produce...

  18. Correcting ligands, metabolites, and pathways

    Directory of Open Access Journals (Sweden)

    Vriend Gert

    2006-11-01

    Full Text Available Abstract Background A wide range of research areas in bioinformatics, molecular biology and medicinal chemistry require precise chemical structure information about molecules and reactions, e.g. drug design, ligand docking, metabolic network reconstruction, and systems biology. Most available databases, however, treat chemical structures more as illustrations than as a datafield in its own right. Lack of chemical accuracy impedes progress in the areas mentioned above. We present a database of metabolites called BioMeta that augments the existing pathway databases by explicitly assessing the validity, correctness, and completeness of chemical structure and reaction information. Description The main bulk of the data in BioMeta were obtained from the KEGG Ligand database. We developed a tool for chemical structure validation which assesses the chemical validity and stereochemical completeness of a molecule description. The validation tool was used to examine the compounds in BioMeta, showing that a relatively small number of compounds had an incorrect constitution (connectivity only, not considering stereochemistry and that a considerable number (about one third had incomplete or even incorrect stereochemistry. We made a large effort to correct the errors and to complete the structural descriptions. A total of 1468 structures were corrected and/or completed. We also established the reaction balance of the reactions in BioMeta and corrected 55% of the unbalanced (stoichiometrically incorrect reactions in an automatic procedure. The BioMeta database was implemented in PostgreSQL and provided with a web-based interface. Conclusion We demonstrate that the validation of metabolite structures and reactions is a feasible and worthwhile undertaking, and that the validation results can be used to trigger corrections and improvements to BioMeta, our metabolite database. BioMeta provides some tools for rational drug design, reaction searches, and

  19. Rapid quantitative evaluation of vascular damage in vivo

    International Nuclear Information System (INIS)

    Griem, M.L.; Kramp, D.; Hedge, K.; Dimitrievich, G.

    1987-01-01

    Using the rabbit ear chamber technique (Rad Res 99:511-535) mature vessels are imaged with a photo microscope and video images are digitized by a Quantex image processor. Each digitized image frame continuously updates a background image via exponential averaging. Simultaneously this background image is subtracted from each input frame to form the difference image. The absolute value of this image, in which significant motion artifacts remain, is summed by a second memory until the intensity of the vessel regions has saturated. High pass spacial filter, followed by a band pass look-up table defines vessels as white and non- vessel regions as black except for ''salt and pepper noises.'' Next, the image is read into computer memory which searches for segments of white pixels of satisfactory length. Then either a) the entire segment or b) the mid-point of the segment is ''color-set'' and displayed with the image after final correction a count of the number of set pixels is made. This count is proportional to either a) total vessel area viewed or b) total vessel length. This technique is then used to create histograms of vessel lengths. Intercomparison with the photographic technique is presented for graded doses of radiation, evaluating vascular damage

  20. Correction of Facial Deformity in Sturge–Weber Syndrome

    Science.gov (United States)

    Yamaguchi, Kazuaki; Lonic, Daniel; Chen, Chit

    2016-01-01

    Background: Although previous studies have reported soft-tissue management in surgical treatment of Sturge–Weber syndrome (SWS), there are few reports describing facial bone surgery in this patient group. The purpose of this study is to examine the validity of our multidisciplinary algorithm for correcting facial deformities associated with SWS. To the best of our knowledge, this is the first study on orthognathic surgery for SWS patients. Methods: A retrospective chart review included 2 SWS patients who completed the surgical treatment algorithm. Radiographic and clinical data were recorded, and a treatment algorithm was derived. Results: According to the Roach classification, the first patient was classified as type I presenting with both facial and leptomeningeal vascular anomalies without glaucoma and the second patient as type II presenting only with a hemifacial capillary malformation. Considering positive findings in seizure history and intracranial vascular anomalies in the first case, the anesthetic management was modified to omit hypotensive anesthesia because of the potential risk of intracranial pressure elevation. Primarily, both patients underwent 2-jaw orthognathic surgery and facial bone contouring including genioplasty, zygomatic reduction, buccal fat pad removal, and masseter reduction without major complications. In the second step, the volume and distribution of facial soft tissues were altered by surgical resection and reposition. Both patients were satisfied with the surgical result. Conclusions: Our multidisciplinary algorithm can systematically detect potential risk factors. Correction of the asymmetric face by successive bone and soft-tissue surgery enables the patients to reduce their psychosocial burden and increase their quality of life. PMID:27622111