Dose-related difference in progression rates of cytomegalovirus retinopathy during foscarnet maintenance therapy. AIDS Clinical Trials Group Protocol 915 Team.

Science.gov (United States)

Holland, G N; Levinson, R D; Jacobson, M A

1995-05-01

A previous dose-ranging study of foscarnet maintenance therapy for cytomegalovirus retinopathy showed a positive relationship between dose and survival but could not confirm a relationship between dose and time to first progression. This retrospective analysis of data from that study was undertaken to determine whether there was a relationship between dose and progression rates, which reflects the amount of retina destroyed when progression occurs. Patients were randomly given one of two foscarnet maintenance therapy doses (90 mg/kg of body weight/day [FOS-90 group] or 120 mg/kg of body weight/day [FOS-120 group] after induction therapy. Using baseline and follow-up photographs and pre-established definitions and methodology in a masked analysis, posterior progression rates and foveal proximity rates for individual lesions, selected by prospectively defined criteria, were calculated in each patient. Rates were compared between groups. The following median rates were greater for the FOS-90 group (N = 8) than for the FOS-120 group (N = 10): greatest maximum rate at which lesions enlarged in a posterior direction (43.5 vs 12.5 microns/day; P = .002); posterior progression rate for lesions closest to the fovea (42.8 vs 5.5 microns/day; P = .010); and maximum foveal proximity rate for either eye (32.3 vs 3.4 microns/day; P = .031). Patients receiving higher doses of foscarnet have slower rates of progression and therefore less retinal tissue damage during maintenance therapy. A foscarnet maintenance therapy dose of 120 mg/kg of body weight/day instead of 90 mg/kg of body weight/day may help to preserve vision in patients with cytomegalovirus retinopathy.

Dose escalation using conformal high-dose-rate brachytherapy improves outcome in unfavorable prostate cancer

International Nuclear Information System (INIS)

Martinez, Alvaro A.; Gustafson, Gary; Gonzalez, Jose; Armour, Elwood; Mitchell, Chris; Edmundson, Gregory; Spencer, William; Stromberg, Jannifer; Huang, Raywin; Vicini, Frank

2002-01-01

Purpose: To overcome radioresistance for patients with unfavorable prostate cancer, a prospective trial of pelvic external beam irradiation (EBRT) interdigitated with dose-escalating conformal high-dose-rate (HDR) prostate brachytherapy was performed. Methods and Materials: Between November 1991 and August 2000, 207 patients were treated with 46 Gy pelvic EBRT and increasing HDR brachytherapy boost doses (5.50-11.5 Gy/fraction) during 5 weeks. The eligibility criteria were pretreatment prostate-specific antigen level ≥10.0 ng/mL, Gleason score ≥7, or clinical Stage T2b or higher. Patients were divided into 2 dose levels, low-dose biologically effective dose 93 Gy (149 patients). No patient received hormones. We used the American Society for Therapeutic Radiology and Oncology definition for biochemical failure. Results: The median age was 69 years. The mean follow-up for the group was 4.4 years, and for the low and high-dose levels, it was 7.0 and 3.4 years, respectively. The actuarial 5-year biochemical control rate was 74%, and the overall, cause-specific, and disease-free survival rate was 92%, 98%, and 68%, respectively. The 5-year biochemical control rate for the low-dose group was 52%; the rate for the high-dose group was 87% (p<0.001). Improvement occurred in the cause-specific survival in favor of the brachytherapy high-dose level (p=0.014). On multivariate analysis, a low-dose level, higher Gleason score, and higher nadir value were associated with increased biochemical failure. The Radiation Therapy Oncology Group Grade 3 gastrointestinal/genitourinary complications ranged from 0.5% to 9%. The actuarial 5-year impotency rate was 51%. Conclusion: Pelvic EBRT interdigitated with transrectal ultrasound-guided real-time conformal HDR prostate brachytherapy boost is both a precise dose delivery system and a very effective treatment for unfavorable prostate cancer. We demonstrated an incremental beneficial effect on biochemical control and cause

High-dose preoperative radiation for cancer of the rectum: Impact of radiation dose on patterns of failure and survival

International Nuclear Information System (INIS)

Ahmad, N.R.; Mohiuddin, M.; Marks, G.

1993-01-01

A variety of dose-time schedules are currently used for preoperative radiation therapy of rectal cancer. An analysis of patients treated with high-dose preoperative radiation therapy was undertaken to determine the influence of radiation dose on the patterns of failure, survival, and complications. Two hundred seventy-five patients with localized rectal cancer were treated with high-dose preoperative radiation therapy. One hundred fifty-six patients received 45 Gy (low-dose group). Since 1985, 119 patients with clinically unfavorable cancers were given a higher dose, 55 Gy using a shrinking field technique (high-dose group). All patients underwent curative resection. Median follow-up was 66 months in the low-dose group and 28 months in the high-dose group. Patterns of failure, survival, and complications were analyzed as a function of radiation dose. Fourteen percent of the total group developed a local recurrence; 20% in the low-dose group as compared with 6% in the high-dose group. The actuarial local recurrence rate at 5 years was 20% for the low-dose group and 8% for the high-dose group, and approached statistical significance with p = .057. For tethered/fixed tumors the actuarial local recurrence rates at 5 years were 28% and 9%, respectively, with p = .05. Similarly, for low-lying tumors (less than 6 cm from the anorectal junction) the rates were 24% and 9%, respectively, with p = .04. The actuarial rate of distant metastasis was 28% in the low-dose group and 20% in the high-dose group and was not significantly different. Overall actuarial 5-year survival for the total group of patients was 66%. No significant difference in survival was observed between the two groups, despite the higher proportion of unfavorable cancers in the high-dose group. The incidence of complications was 2%, equally distributed between the two groups. High-dose preoperative radiation therapy for rectal cancer results in excellent local control rates. 27 refs., 2 figs., 8 tabs

Women Administered Standard Dose Imatinib for Chronic Myeloid Leukemia Have Higher Dose-Adjusted Plasma Imatinib and Norimatinib Concentrations Than Men.

Science.gov (United States)

Belsey, Sarah L; Ireland, Robin; Lang, Kathryn; Kizilors, Aytug; Ho, Aloysius; Mufti, Ghulam J; Bisquera, Alessandra; De Lavallade, Hugues; Flanagan, Robert J

2017-10-01

The standard dose of imatinib for the treatment of chronic-phase chronic myeloid leukemia (CML) is 400 mg·d. A predose plasma imatinib concentration of >1 mg·L is associated with improved clinical response. This study aimed to assess the plasma imatinib and norimatinib concentrations attained in patients with chronic myeloid leukemia administered standard doses of imatinib adjusted for dose, age, sex, body weight, and response. We evaluated data from a cohort of patients treated between 2008 and 2014 with respect to dose, age, sex, body weight, and response. The study comprised 438 samples from 93 patients (54 male, 39 female). The median imatinib dose was 400 mg·d in men and in women. The plasma imatinib concentration ranged 0.1-5.0 mg·L and was below 1 mg·L in 20% and 16% of samples from men and women, respectively. The mean dose normalized plasma imatinib and norimatinib concentrations were significantly higher in women in comparison with men. This was partially related to body weight. Mixed effects ordinal logistic regression showed no evidence of an association between sex and plasma imatinib (P = 0.13). However, there was evidence of an association between sex and plasma norimatinib, with higher norimatinib concentrations more likely in women than in men (P = 0.02). Imatinib therapeutic drug monitoring only provides information on dosage adequacy and on short-term adherence; longer-term adherence cannot be assessed. However, this analysis revealed that approximately 1 in 5 samples had a plasma imatinib concentration <1 mg·L, which was suggestive of inadequate dosage and/or poor adherence and posed a risk of treatment failure. Higher imatinib exposure in women may be a factor in the increased rate of long-term, stable, deep molecular response (undetectable breakpoint cluster-Abelson (BCR-ABL) transcript levels with a PCR sensitivity of 4.5 log, MR4.5) reported in women.

A Phase I Study of the Safety and Pharmacokinetics of Higher-Dose Icotinib in Patients With Advanced Non-Small Cell Lung Cancer.

Science.gov (United States)

Liu, Jian; Wu, Lihua; Wu, Guolan; Hu, Xingjiang; Zhou, Huili; Chen, Junchun; Zhu, Meixiang; Xu, Wei; Tan, Fenlai; Ding, Lieming; Wang, Yinxiang; Shentu, Jianzhong

2016-11-01

This phase I study evaluated the maximum tolerated dose, dose-limiting toxicities, safety, pharmacokinetics, and efficacy of icotinib with a starting dose of 250 mg in pretreated, advanced non-small cell lung cancer patients. We observed a maximum tolerated dose of 500 mg with a favorable pharmacokinetics profile and antitumor activity.These findings provide clinicians with evidence for application of higher-dose icotinib. Icotinib, an oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, has shown favorable tolerability and antitumor activity at 100-200 mg in previous studies without reaching the maximum tolerated dose (MTD). In July 2011, icotinib was approved by the China Food and Drug Administration at a dose of 125 mg three times daily for the treatment of patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) after failure of at least one platinum-based chemotherapy regimen. This study investigated the MTD, tolerability, and pharmacokinetics of higher-dose icotinib in patients with advanced NSCLC. Twenty-six patients with advanced NSCLC were treated at doses of 250-625 mg three times daily The EGFR mutation test was not mandatory in this study. Twenty-four (92.3%) of 26 patients experienced at least one adverse event (AE); rash (61.5%), diarrhea (23.1%), and oral ulceration (11.5%) were most frequent AEs. Dose-limiting toxicities were seen in 2 of 6 patients in the 625-mg group, and the MTD was established at 500 mg. Icotinib was rapidly absorbed and eliminated. The amount of time that the drug was present at the maximum concentration in serum (T max ) ranged from 1 to 3 hours (1.5-4 hours) after multiple doses. The t 1/2 was similar after single- and multiple-dose administration (7.11 and 6.39 hours, respectively). A nonlinear relationship was observed between dose and drug exposure. Responses were seen in 6 (23.1%) patients, and 8 (30.8%) patients had stable disease. This study demonstrated that higher-dose

Assessment of dose to the critical group and the world population

International Nuclear Information System (INIS)

Coulon, R.

1978-01-01

This paper reviews the basic principles of radiation protection and analyses the exposure of the public through radioactive transfers. The evaluation of the dose to the ''critical group'' is described and an application of the philosophy is proposed. A parallel study is conducted in the case of the evaluation of the dose to the world population. (author)

Higher class groups of Eichler orders

International Nuclear Information System (INIS)

Guo Xuejun; Kuku, Aderemi

2003-11-01

In this paper, we prove that if A is a quaternion algebra and Λ an Eichler order in A, then the only p-torsion possible in even dimensional higher class groups Cl 2n (Λ) (n ≥ 1) are for those rational primes p which lie under prime ideals of O F at which Λ are not maximal. (author)

Risk group dependence of dose-response for biopsy outcome after three-dimensional conformal radiation therapy of prostate cancer

International Nuclear Information System (INIS)

Levegruen, Sabine; Jackson, Andrew; Zelefsky, Michael J.; Venkatraman, Ennapadam S.; Skwarchuk, Mark W.; Schlegel, Wolfgang; Fuks, Zvi; Leibel, Steven A.; Ling, C. Clifton

2002-01-01

Background and purpose: We fit phenomenological tumor control probability (TCP) models to biopsy outcome after three-dimensional conformal radiation therapy (3D-CRT) of prostate cancer patients to quantify the local dose-response of prostate cancer. Materials and methods: We analyzed the outcome after photon beam 3D-CRT of 103 patients with stage T1c-T3 prostate cancer treated at Memorial Sloan-Kettering Cancer Center (MSKCC) (prescribed target doses between 64.8 and 81 Gy) who had a prostate biopsy performed ≥2.5 years after end of treatment. A univariate logistic regression model based on D mean (mean dose in the planning target volume of each patient) was fit to the whole data set and separately to subgroups characterized by low and high values of tumor-related prognostic factors T-stage ( 6), and pre-treatment prostate-specific antigen (PSA) (≤10 ng/ml vs. >10 ng/ml). In addition, we evaluated five different classifications of the patients into three risk groups, based on all possible combinations of two or three prognostic factors, and fit bivariate logistic regression models with D mean and the risk group category to all patients. Dose-response curves were characterized by TCD 50 , the dose to control 50% of the tumors, and γ 50 , the normalized slope of the dose-response curve at TCD 50 . Results: D mean correlates significantly with biopsy outcome in all patient subgroups and larger values of TCD 50 are observed for patients with unfavorable compared to favorable prognostic factors. For example, TCD 50 for high T-stage patients is 7 Gy higher than for low T-stage patients. For all evaluated risk group definitions, D mean and the risk group category are independent predictors of biopsy outcome in bivariate analysis. The fit values of TCD 50 show a clear separation of 9-10.6 Gy between low and high risk patients. The corresponding dose-response curves are steeper (γ 50 =3.4-5.2) than those obtained when all patients are analyzed together (γ 50 =2

Dose escalation using conformal high-dose-rate brachytherapy improves outcome in unfavorable prostate cancer.

Science.gov (United States)

Martinez, Alvaro A; Gustafson, Gary; Gonzalez, José; Armour, Elwood; Mitchell, Chris; Edmundson, Gregory; Spencer, William; Stromberg, Jannifer; Huang, Raywin; Vicini, Frank

2002-06-01

To overcome radioresistance for patients with unfavorable prostate cancer, a prospective trial of pelvic external beam irradiation (EBRT) interdigitated with dose-escalating conformal high-dose-rate (HDR) prostate brachytherapy was performed. Between November 1991 and August 2000, 207 patients were treated with 46 Gy pelvic EBRT and increasing HDR brachytherapy boost doses (5.50-11.5 Gy/fraction) during 5 weeks. The eligibility criteria were pretreatment prostate-specific antigen level >or=10.0 ng/mL, Gleason score >or=7, or clinical Stage T2b or higher. Patients were divided into 2 dose levels, low-dose biologically effective dose 93 Gy (149 patients). No patient received hormones. We used the American Society for Therapeutic Radiology and Oncology definition for biochemical failure. The median age was 69 years. The mean follow-up for the group was 4.4 years, and for the low and high-dose levels, it was 7.0 and 3.4 years, respectively. The actuarial 5-year biochemical control rate was 74%, and the overall, cause-specific, and disease-free survival rate was 92%, 98%, and 68%, respectively. The 5-year biochemical control rate for the low-dose group was 52%; the rate for the high-dose group was 87% (p failure. The Radiation Therapy Oncology Group Grade 3 gastrointestinal/genitourinary complications ranged from 0.5% to 9%. The actuarial 5-year impotency rate was 51%. Pelvic EBRT interdigitated with transrectal ultrasound-guided real-time conformal HDR prostate brachytherapy boost is both a precise dose delivery system and a very effective treatment for unfavorable prostate cancer. We demonstrated an incremental beneficial effect on biochemical control and cause-specific survival with higher doses. These results, coupled with the low risk of complications, the advantage of not being radioactive after implantation, and the real-time interactive planning, define a new standard for treatment.

Bioavailability of higher dose methotrexate comparing oral and subcutaneous administration in patients with rheumatoid arthritis

NARCIS (Netherlands)

Hoekstra, Monique; Haagsma, C.; Neef, C; Proost, Johannes H; Knuif, A.; van der Laar, M.

Objective. To determine the bioavailability of higher oral doses of methotrexate (MTX) in adult patients with rheumatoid arthritis (RA). Methods. A pharmacokinetic analysis was performed in 15 patients with RA taking a stable dose of MTX (greater than or equal to25 mg weekly). Separated by 2 weeks,

Dose to patients and professionals in cardiology interventional: Progress of multicenter group Doccaci

International Nuclear Information System (INIS)

Sanchez, R. M.; Vano, E.; Fernandez, J. M.; Goicolea Ruigomez, J.; Pifarre, X.; Escaned, J.; Rovira, J. J.; Garcia del Blanco, B.; Carrera, F.; Diaz, J. F.; Ordiales, J. M.; Nogales, J. M.; Hernandez, J.; Bosa, F.; Rosales, F.; Saez, J. R.; Soler, M. M.; Romero, M. A.

2013-01-01

The multidisciplinary group and multicenter DOCCACI (dosimetry and quality assurance in interventional cardiology), sponsored by the section of haemodynamics of the Spanish society of Cardiology, is intended to propose reference levels to doses received by patients in interventional cardiology procedures such as recommended by the International Commission on radiological protection It also investigates the doses received by professionals, in particular dose in Crystallyne whose recommended limit dose has been reduced recently from 150 to 20 mSv/year. (Author)

Homing regularity of different doses bone marrow transplantation in allogeneic hosts

International Nuclear Information System (INIS)

Sun Suping; Cai Jianming; Xiang Yingsong; Zhao Fang; Huang Dingde; Gao Jianguo; Yang Rujun

2001-01-01

Objective: To explore the homing regularity of different doses of bone marrow cell transplantation. Method: An allogeneic mouse model was used. The homing status of different dose groups from the first day to the forth day after transplantation were observed. Results: The rate of positive cells in bone marrow and spleen: differences among four groups was not significant. The rate of positive cells of third day was highest among four days (P<0.01). A phenomenon that homing-mobilization-re-homing could be observed. The homing efficiency: low dose groups were higher than that high dose groups (P<0.01). Conclusion: The homing efficiency of low dose groups is higher than that of the high dose groups in certain range, the routine method of transplanting a large quantities cells by a single injection may be an waste

Higher Biologically Effective Dose of Radiotherapy Is Associated With Improved Outcomes for Locally Advanced Non–Small Cell Lung Carcinoma Treated With Chemoradiation: An Analysis of the Radiation Therapy Oncology Group

International Nuclear Information System (INIS)

Machtay, Mitchell; Bae, Kyounghwa; Movsas, Benjamin; Paulus, Rebecca; Gore, Elizabeth M.; Komaki, Ritsuko; Albain, Kathy; Sause, William T.; Curran, Walter J.

2012-01-01

Purpose: Patients treated with chemoradiotherapy for locally advanced non–small-cell lung carcinoma (LA-NSCLC) were analyzed for local-regional failure (LRF) and overall survival (OS) with respect to radiotherapy dose intensity. Methods and Materials: This study combined data from seven Radiation Therapy Oncology Group (RTOG) trials in which chemoradiotherapy was used for LA-NSCLC: RTOG 88-08 (chemoradiation arm only), 90-15, 91-06, 92-04, 93-09 (nonoperative arm only), 94-10, and 98-01. The radiotherapeutic biologically effective dose (BED) received by each individual patient was calculated, as was the overall treatment time-adjusted BED (tBED) using standard formulae. Heterogeneity testing was done with chi-squared statistics, and weighted pooled hazard ratio estimates were used. Cox and Fine and Gray’s proportional hazard models were used for OS and LRF, respectively, to test the associations between BED and tBED adjusted for other covariates. Results: A total of 1,356 patients were analyzed for BED (1,348 for tBED). The 2-year and 5-year OS rates were 38% and 15%, respectively. The 2-year and 5-year LRF rates were 46% and 52%, respectively. The BED (and tBED) were highly significantly associated with both OS and LRF, with or without adjustment for other covariates on multivariate analysis (p < 0.0001). A 1-Gy BED increase in radiotherapy dose intensity was statistically significantly associated with approximately 4% relative improvement in survival; this is another way of expressing the finding that the pool-adjusted hazard ratio for survival as a function of BED was 0.96. Similarly, a 1-Gy tBED increase in radiotherapy dose intensity was statistically significantly associated with approximately 3% relative improvement in local-regional control; this is another way of expressing the finding that the pool-adjusted hazard ratio as a function of tBED was 0.97. Conclusions: Higher radiotherapy dose intensity is associated with improved local-regional control

Variable effects of high-dose adrenaline relative to standard-dose adrenaline on resuscitation outcomes according to cardiac arrest duration.

Science.gov (United States)

Jeung, Kyung Woon; Ryu, Hyun Ho; Song, Kyung Hwan; Lee, Byung Kook; Lee, Hyoung Youn; Heo, Tag; Min, Yong Il

2011-07-01

Adjustment of adrenaline (epinephrine) dosage according to cardiac arrest (CA) duration, rather than administering the same dose, may theoretically improve resuscitation outcomes. We evaluated variable effects of high-dose adrenaline (HDA) relative to standard-dose adrenaline (SDA) on resuscitation outcomes according to CA duration. Twenty-eight male domestic pigs were randomised to the following 4 groups according to the dosage of adrenaline (SDA 0.02 mg/kg vs. HDA 0.2mg/kg) and duration of CA before beginning cardiopulmonary resuscitation (CPR): 6 min SDA, 6 min HDA, 13 min SDA, or 13 min HDA. After the predetermined duration of untreated ventricular fibrillation, CPR was provided. All animals in the 6 min SDA, 6 min HDA, and 13 min HDA groups were successfully resuscitated, while only 4 of 7 pigs in the 13 min SDA group were successfully resuscitated (p=0.043). HDA groups showed higher right atrial pressure, more frequent ventricular ectopic beats, higher blood glucose, higher troponin-I, and more severe metabolic acidosis than SDA groups. Animals of 13 min groups showed more severe metabolic acidosis and higher troponin-I than animals of 6 min groups. All successfully resuscitated animals, except two animals in the 13 min HDA group, survived for 7 days (p=0.121). Neurologic deficit score was not affected by the dose of adrenaline. HDA showed benefit in achieving restoration of spontaneous circulation in 13 min CA, when compared with 6 min CA. However, this benefit did not translate into improved long-term survival or neurologic outcome. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Dose-to-medium vs. dose-to-water: Dosimetric evaluation of dose reporting modes in Acuros XB for prostate, lung and breast cancer

Directory of Open Access Journals (Sweden)

Suresh Rana

2014-12-01

Full Text Available Purpose: Acuros XB (AXB dose calculation algorithm is available for external beam photon dose calculations in Eclipse treatment planning system (TPS. The AXB can report the absorbed dose in two modes: dose-to-water (Dw and dose-to-medium (Dm. The main purpose of this study was to compare the dosimetric results of the AXB_Dm with that of AXB_Dw on real patient treatment plans. Methods: Four groups of patients (prostate cancer, stereotactic body radiation therapy (SBRT lung cancer, left breast cancer, and right breast cancer were selected for this study, and each group consisted of 5 cases. The treatment plans of all cases were generated in the Eclipse TPS. For each case, treatment plans were computed using AXB_Dw and AXB_Dm for identical beam arrangements. Dosimetric evaluation was done by comparing various dosimetric parameters in the AXB_Dw plans with that of AXB_Dm plans for the corresponding patient case. Results: For the prostate cancer, the mean planning target volume (PTV dose in the AXB_Dw plans was higher by up to 1.0%, but the mean PTV dose was within ±0.3% for the SBRT lung cancer. The analysis of organs at risk (OAR results in the prostate cancer showed that AXB_Dw plans consistently produced higher values for the bladder and femoral heads but not for the rectum. In the case of SBRT lung cancer, a clear trend was seen for the heart mean dose and spinal cord maximum dose, with AXB_Dw plans producing higher values than the AXB_Dm plans. However, the difference in the lung doses between the AXB_Dm and AXB_Dw plans did not always produce a clear trend, with difference ranged from -1.4% to 2.9%. For both the left and right breast cancer, the AXB_Dm plans produced higher maximum dose to the PTV for all cases. The evaluation of the maximum dose to the skin showed higher values in the AXB_Dm plans for all 5 left breast cancer cases, whereas only 2 cases had higher maximum dose to the skin in the AXB_Dm plans for the right breast cancer

Patient grouping for dose surveys and establishment of diagnostic reference levels in paediatric computed tomography

International Nuclear Information System (INIS)

Vassileva, J.; Rehani, M.

2015-01-01

There has been confusion in literature on whether paediatric patients should be grouped according to age, weight or other parameters when dealing with dose surveys. The present work aims to suggest a pragmatic approach to achieve reasonable accuracy for performing patient dose surveys in countries with limited resources. The analysis is based on a subset of data collected within the IAEA survey of paediatric computed tomography (CT) doses, involving 82 CT facilities from 32 countries in Asia, Europe, Africa and Latin America. Data for 6115 patients were collected, in 34.5 % of which data for weight were available. The present study suggests that using four age groups, <1, >1-5, >5-10 and >10-15 y, is realistic and pragmatic for dose surveys in less resource countries and for the establishment of DRLs. To ensure relevant accuracy of results, data for >30 patients in a particular age group should be collected if patient weight is not known. If a smaller sample is used, patient weight should be recorded and the median weight in the sample should be within 5-10 % from the median weight of the sample for which the DRLs were established. Comparison of results from different surveys should always be performed with caution, taking into consideration the way of grouping of paediatric patients. Dose results can be corrected for differences in patient weight/age group. (authors)

Clinical value of CARE dose 4D technique in decreasing CT scanning dose of adult chest

International Nuclear Information System (INIS)

Wu Aiqin; Zheng Wenlong; Xu Chongyong; Fang Bidong; Ge Wen

2011-01-01

Objective: To investigate the value of CARE Dose 4D technique in decreasing radiation dose and improving image quality of multi-slice spiral CT in adult chest scanning. Methods: 100 patients of chest CT scanning were equally divided into study group and control group randomly. CARE Dose 4D Technique was used in study group. Effective mAs value, volume CT dose index (CTDI vol ) and dose length product (DLP) were displayed automatically in machine while chest scanning; those values and actual mAs value of every image were recorded respectively. The image quality at apex of lung, lower edge of aorta arch, middle area of left atrium and base of lung on every image of 400 images was judged and classified as three level (excellent, good, poor) by two deputy chief physicians with double blind method, the image noise at corresponding parts was measured. Results: While setting 80 mAs for quality reference mAs, the effective mAs value in study group most decreased 44 mAs than control group with an average decrease of 9.60 (12.0%), CTDI vol with 4.75 mGy with an average decrease of 0.95 mCy (11.0%), DLP 99.50% in study group, with 98.0% in control group. But it was higher at apex of lung and base of lung, lower at middle area of left atrium, and similar at lower edge of aorta arch in study group than contrast group. The image noise were lower at apex of lung and base of lung in study group than control group (t =6.299 and 2.332, all P<0.05), higher at middle area of left atrium in study group than control group (t=3.078, P<0.05) and similar at lower edge of aorta arch in study group than control group (t=1.191, P>0.05). Conclusions: CARE Dose 4D technique provides a function regulated mAs real-time on line, it not only raises utilization rate of radiation and decreases radiation dose, but also promises and increases image quality in chest CT scanning, and has some clinical significance. (authors)

Higher glucocorticoid replacement doses are associated with increased mortality in patients with pituitary adenoma.

Science.gov (United States)

Hammarstrand, Casper; Ragnarsson, Oskar; Hallén, Tobias; Andersson, Eva; Skoglund, Thomas; Nilsson, Anna G; Johannsson, Gudmundur; Olsson, Daniel S

2017-09-01

Patients with secondary adrenal insufficiency (AI) have an excess mortality. The objective was to investigate the impact of the daily glucocorticoid replacement dose on mortality in patients with hypopituitarism due to non-functioning pituitary adenoma (NFPA). Patients with NFPA were followed between years 1997 and 2014 and cross-referenced with the National Swedish Death Register. Standardized mortality ratio (SMR) was calculated with the general population as reference and Cox-regression was used to analyse the mortality. The analysis included 392 patients (140 women) with NFPA. Mean ± s.d. age at diagnosis was 58.7 ± 14.6 years and mean follow-up was 12.7 ± 7.2 years. AI was present in 193 patients, receiving a mean daily hydrocortisone equivalent (HCeq) dose of 20 ± 6 mg. SMR (95% confidence interval (CI)) for patients with AI was similar to that for patients without, 0.88 (0.68-1.12) and 0.87 (0.63-1.18) respectively. SMR was higher for patients with a daily HCeq dose of >20 mg (1.42 (0.88-2.17)) than that in patients with a daily HCeq dose of 20 mg (0.71 (0.49-0.99)), P  = 0.017. In a Cox-regression analysis, a daily HCeq dose of >20 mg was independently associated with a higher mortality (HR: 1.88 (1.06-3.33)). Patients with daily HCeq doses of ≤20 mg had a mortality risk comparable to patients without glucocorticoid replacement and to the general population. Patients with NFPA and AI receiving more than 20 mg HCeq per day have an increased mortality. Our data also show that mortality in patients substituted with 20 mg HCeq per day or less is not increased. © 2017 European Society of Endocrinology.

Gender-heterogeneous working groups produce higher quality science.

Directory of Open Access Journals (Sweden)

Lesley G Campbell

Full Text Available Here we present the first empirical evidence to support the hypothesis that a gender-heterogeneous problem-solving team generally produced journal articles perceived to be higher quality by peers than a team comprised of highly-performing individuals of the same gender. Although women were historically underrepresented as principal investigators of working groups, their frequency as PIs at the National Center for Ecological Analysis and Synthesis is now comparable to the national frequencies in biology and they are now equally qualified, in terms of their impact on the accumulation of ecological knowledge (as measured by the h-index. While women continue to be underrepresented as working group participants, peer-reviewed publications with gender-heterogeneous authorship teams received 34% more citations than publications produced by gender-uniform authorship teams. This suggests that peers citing these publications perceive publications that also happen to have gender-heterogeneous authorship teams as higher quality than publications with gender uniform authorship teams. Promoting diversity not only promotes representation and fairness but may lead to higher quality science.

Gender-heterogeneous working groups produce higher quality science.

Science.gov (United States)

Campbell, Lesley G; Mehtani, Siya; Dozier, Mary E; Rinehart, Janice

2013-01-01

Here we present the first empirical evidence to support the hypothesis that a gender-heterogeneous problem-solving team generally produced journal articles perceived to be higher quality by peers than a team comprised of highly-performing individuals of the same gender. Although women were historically underrepresented as principal investigators of working groups, their frequency as PIs at the National Center for Ecological Analysis and Synthesis is now comparable to the national frequencies in biology and they are now equally qualified, in terms of their impact on the accumulation of ecological knowledge (as measured by the h-index). While women continue to be underrepresented as working group participants, peer-reviewed publications with gender-heterogeneous authorship teams received 34% more citations than publications produced by gender-uniform authorship teams. This suggests that peers citing these publications perceive publications that also happen to have gender-heterogeneous authorship teams as higher quality than publications with gender uniform authorship teams. Promoting diversity not only promotes representation and fairness but may lead to higher quality science.

Analysis of CT radiation dose based on radiation-dose-structured reports

International Nuclear Information System (INIS)

Wang Weipeng; Zhang Yi; Zhang Menglong; Zhang Dapeng; Song Shaojuan

2014-01-01

Objective: To analyse the CT radiation dose statistically using the standardized radiation-dose-structured report (RDSR) of digital imaging and communications in medicine (DICOM). Methods: Using the self-designed software, 1230 RDSR files about CT examination were obtained searching on the picture archiving and communication system (PACS). The patient dose database was established by combination of the extracted relevant information with the scanned sites. The patients were divided into adult group (over 10 years) and child groups (0-1 year, 1-5 years, 5-10 years) according to the age. The average volume CT dose index (CTDI vol ) and dose length product (DLP) of all scans were recorded respectively, and then the effective dose (E) was estimated. The DLP value at 75% quantile was calculated and compared with the diagnostic reference level (DRL). Results: In adult group, CTDI vol and DLP values were moderately and positively correlated (r = 0.41), the highest E was observed in upper abdominal enhanced scan, and the DLP value at 75% quantile was 60% higher than DRL. In child group, their CTDI vol in group of 5-10 years was greater than that in groups of 0-1 and 1-5 years (t = 2.42, 2.04, P < 0.05); the DLP value was slightly and positively correlated with the age (r = 0.16), while E was moderately and negatively correlated with the age (r = -0.48). Conclusions: It is a simple and efficient method to use RDSR to obtain the radiation doses of patients. With the popularization of the new equipment and the application of regionalized medical platform, RDSR would become the main tool for the dosimetric level surveying and individual dose recording. (authors)

Critical groups vs. representative person: dose calculations due to predicted releases from USEXA

Energy Technology Data Exchange (ETDEWEB)

Ferreira, N.L.D., E-mail: nelson.luiz@ctmsp.mar.mil.br [Centro Tecnologico da Marinha (CTM/SP), Sao Paulo, SP (Brazil); Rochedo, E.R.R., E-mail: elainerochedo@gmail.com [Instituto de Radiprotecao e Dosimetria (lRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Mazzilli, B.P., E-mail: mazzilli@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

The critical group cf Centro Experimental Aramar (CEA) site was previously defined based 00 the effluents releases to the environment resulting from the facilities already operational at CEA. In this work, effective doses are calculated to members of the critical group considering the predicted potential uranium releases from the Uranium Hexafluoride Production Plant (USEXA). Basically, this work studies the behavior of the resulting doses related to the type of habit data used in the analysis and two distinct situations are considered: (a) the utilization of average values obtained from official institutions (IBGE, IEA-SP, CNEN, IAEA) and from the literature; and (b) the utilization of the 95{sup tb} percentile of the values derived from distributions fit to the obtained habit data. The first option corresponds to the way that data was used for the definition of the critical group of CEA done in former assessments, while the second one corresponds to the use of data in deterministic assessments, as recommended by ICRP to estimate doses to the so--called 'representative person' . (author)

Critical groups vs. representative person: dose calculations due to predicted releases from USEXA

International Nuclear Information System (INIS)

Ferreira, N.L.D.; Rochedo, E.R.R.; Mazzilli, B.P.

2013-01-01

The critical group cf Centro Experimental Aramar (CEA) site was previously defined based 00 the effluents releases to the environment resulting from the facilities already operational at CEA. In this work, effective doses are calculated to members of the critical group considering the predicted potential uranium releases from the Uranium Hexafluoride Production Plant (USEXA). Basically, this work studies the behavior of the resulting doses related to the type of habit data used in the analysis and two distinct situations are considered: (a) the utilization of average values obtained from official institutions (IBGE, IEA-SP, CNEN, IAEA) and from the literature; and (b) the utilization of the 95 tb percentile of the values derived from distributions fit to the obtained habit data. The first option corresponds to the way that data was used for the definition of the critical group of CEA done in former assessments, while the second one corresponds to the use of data in deterministic assessments, as recommended by ICRP to estimate doses to the so--called 'representative person' . (author)

Using higher doses to compensate for tubing residuals in extended-infusion piperacillin-tazobactam.

Science.gov (United States)

Lam, Wendy J; Bhowmick, Tanaya; Gross, Alan; Vanschooneveld, Trevor C; Weinstein, Melvin P

2013-06-01

To mathematically assess drug losses due to infusion line residuals and evaluate methods to compensate for drug loss due to residual volumes in intravenous pump tubing. Literature was accessed through Ovid MEDLINE (1996-February 2013), using combinations of the search terms tubing residuals, residual volume, residual medication, intravenous infusions, intravenous injections, piperacillin, piperacillin-tazobactam, β-lactams, equipment design, infusion pumps, extended infusion, extended administration, and prolonged infusion. In addition, select reference citations from publications identified were reviewed. All articles that involved extended-infusion piperacillin-tazobactam implementation strategies were included in the review. Infusion pump characteristics and tubing residuals can affect extended-infusion piperacillin-tazobactam dosing strategies. Two studies addressing tubing residuals were identified. Both studies recommended increasing infusion volumes to compensate for tubing residuals. One study also recommended decreasing infusion-line dead space by using alternative infusion pump systems. Study calculations suggest that higher doses of piperacillin-tazobactam may be used to account for medication left in tubing residuals if alternative infusion pump systems cannot be obtained, and increased infusion volumes are not an option. Extended-infusion piperacillin-tazobactam has been used as a method of maximizing pharmacodynamic target attainment. Use of higher doses of piperacillin-tazobactam may be a reasonable method to compensate for drug loss due to residual volumes in large-bore intravenous pump tubing.

Bioavailibility of higher dose methotrexate comparing oral and subcutaneous route of administration in patients with rheumatoid arthritis

NARCIS (Netherlands)

Hoekstra, Monique; Hoekstra, M.; Haagsma, Cees; Neef, Cees; Proost, Johannes; van de Laar, Mart A F J; Knuif, Antonius

2004-01-01

OBJECTIVE: To determine the bioavailability of higher oral doses of methotrexate (MTX) in adult patients with rheumatoid arthritis (RA). METHODS: A pharmacokinetic analysis was performed in 15 patients with RA taking a stable dose of MTX (> or = 25 mg weekly). Separated by 2 weeks, a pharmacokinetic

New dose limits and distribution of annual doses for controlled groups

International Nuclear Information System (INIS)

Vukcevic, M.; Stankovic, S.; Kovacevic, M.

1993-01-01

The new calculations of neutron doses received by the population of Hiroshima and Nagasaki, as well as the epidemiological data on the incidence of fatal cancers in the survivors, had led to the conclusion that the risk estimates should be raised by the factor 2 or 3. In this work, the distribution of monthly doses for occupationals was analysed in order to determine the percent of workers who might be considered as overexposed, on the basis of the new dose limits. (author)

Radiation dose to procedural personnel and patients from an X-ray volume imaging system

International Nuclear Information System (INIS)

Paul, Jijo; Mbalisike, Emmanuel C.; Vogl, Thomas J.

2013-01-01

To evaluate the radiation dose received by procedural personnel and patients from an X-ray volume imaging (XVI) system during interventional procedures. Forty patients were examined using catheter angiography (group A), digital subtraction angiography (group B) and cone-beam CT (CBCT, group C). Doses to procedural personnel (using thermo-luminescent dosimeters, TLDs) and patients were estimated. Image quality and lesion delineation were assessed using objective and subjective methods. Shapiro-Wilk, two-sided Student's t and Wilcoxon matched-pairs tests were used to test statistical significance. Doses (milligrays) measured in the hands and left knee of the interventionist were higher than those in an assistant physician (P < 0.05). Doses (dose-area product and skin entry dose) were lower in group A and higher in C compared with other groups; moreover, comparison among the groups were significant (all P = 0.0001). Subjective and objective lesion delineation showed significant results (all P < 0.05) among the tumour types considered. Image quality estimation showed the opposite results for objective and subjective analysis. More doses were obtained for hands of the procedural personnel compared to other anatomical regions measured. Catheter angiography showed lower dose compared with other imaging groups examined. Lesion delineation was clearly possible using CBCT. Objective and subjective analysis showed the opposite results regarding image quality because of higher noise levels and artefacts. (orig.)

Effective equivalent dose in the critical group due to release of radioactive effluents

International Nuclear Information System (INIS)

Santos, John W.A. dos; Varandas, Luciana R.; Souza, Denise N.; Souza, Cristiano B.F.; Lima, Sandro Leonardo N.; Mattos, Marcos Fernando M.; Moraes, Jose Adenildo T.

2005-01-01

To ensure that the emissions of radioactive material by liquid and gaseous pathways are below applicable limits it is necessary to evaluate the effective equivalent dose in the critical group, which is a magnitude that takes into consideration the modeling used and the terms radioactive activity source. The calculation of this dose considers each radionuclide released by the activity of Nuclear plant, liquid and gaseous by, and the sum of the values obtained is controlled so that this dose does not exceed the goals of the regulatory body, the CNEN and the goals established by the Nuclear power plant. To hit these targets various controls are used such as: controls for effluent monitors instrumentation, environmental monitoring programs, effluent release controls and dose calculation in the environment. According to the findings, it is concluded that during the period of operation of the plants, this dose is below of the required limits

Higher cerebral oxygen saturation may provide higher urinary output during continuous regional cerebral perfusion

Directory of Open Access Journals (Sweden)

Tomoyasu Takahiro

2008-10-01

Full Text Available Abstract Objective We examined the hypothesis that higher cerebral oxygen saturation (rSO2 during RCP is correlated with urinary output. Methods Between December 2002 and August 2006, 12 patients aged 3 to 61 days and weighing 2.6 to 3.4 kg underwent aortic arch repair with RCP. Urinary output and rSO2 were analyzed retrospectively. Data were assigned to either of 2 groups according to their corresponding rSO2: Group A (rSO2 ≦ 75% and Group B (rSO2 Results Seven and 5 patients were assigned to Group A and Group B, respectively. Group A was characterized by mean radial arterial pressure (37.9 ± 9.6 vs 45.8 ± 7.8 mmHg; P = 0.14 and femoral arterial pressure (6.7 ± 6.1 vs 20.8 ± 14.6 mmHg; P = 0.09 compared to Group B. However, higher urinary output during CPB (1.03 ± 1.18 vs 0.10 ± 0.15 ml·kg-1·h-1; P = 0.03. Furthermore our results indicate that a higher dose of Chlorpromazine was used in Group A (2.9 ± 1.4 vs 1.7 ± 1.0 mg/kg; P = 0.03. Conclusion Higher cerebral oxygenation may provide higher urinary output due to higher renal blood flow through collateral circulation.

A single dose of oxytocin nasal spray improves higher-order social cognition in schizophrenia.

Science.gov (United States)

Guastella, Adam J; Ward, Philip B; Hickie, Ian B; Shahrestani, Sara; Hodge, Marie Antoinette Redoblado; Scott, Elizabeth M; Langdon, Robyn

2015-11-01

Schizophrenia is associated with significant impairments in both higher and lower order social cognitive performance and these impairments contribute to poor social functioning. People with schizophrenia report poor social functioning to be one of their greatest unmet treatment needs. Recent studies have suggested the potential of oxytocin as such a treatment, but mixed results render it uncertain what aspects of social cognition are improved by oxytocin and, subsequently, how oxytocin might best be applied as a therapeutic. The aim of this study was to determine whether a single dose of oxytocin improved higher-order and lower-order social cognition performance for patients with schizophrenia across a well-established battery of social cognition tests. Twenty-one male patients received both a single dose of oxytocin nasal spray (24IU) and a placebo, two weeks apart in a randomized within-subjects placebo controlled design. Following each administration, participants completed the social cognition tasks, as well as a test of general neurocognition. Results revealed that oxytocin particularly enhanced performance on higher order social cognition tasks, with no effects on general neurocognition. Results for individual tasks showed most improvement on tests measuring appreciation of indirect hints and recognition of social faux pas. These results suggest that oxytocin, if combined to enhance social cognition learning, may be beneficial when targeted at higher order social cognition domains. This study also suggests that these higher order tasks, which assess social cognitive processing in a social communication context, may provide useful markers of response to oxytocin in schizophrenia. Copyright © 2015 Elsevier B.V. All rights reserved.

Alternative dosing of prophylactic enoxaparin in the trauma patient: is more the answer?

Science.gov (United States)

Kopelman, Tammy R; O'Neill, Patrick J; Pieri, Paola G; Salomone, Jeffrey P; Hall, Scott T; Quan, Asia; Wells, Jordan R; Pressman, Melissa S

2013-12-01

Inadequate anti-factor Xa levels and increased venous thromboembolic events occur in trauma patients receiving standard prophylactic enoxaparin dosing. The aim of this study was to test the hypothesis that higher dosing (40 mg twice daily) would improve peak anti-Xa levels and decrease venous thromboembolism. A retrospective review was performed of trauma patients who received prophylactic enoxaparin and peak anti-Xa levels over 27 months. Patients were divided on the basis of dose: group A received 30 mg twice daily, and group B received 40 mg twice daily. Demographics and rates of venous thromboembolism were compared between dose groups and patients with inadequate or adequate anti-Xa levels. One hundred twenty-four patients were included, 90 in group A and 34 in group B. Demographics were similar, except that patients in group B had a higher mean body weight. Despite this, only 9% of group B patients had inadequate anti-Xa levels, compared with 33% of those in group A (P = .01). Imaging studies were available in 69 patients and revealed 8 venous thromboembolic events (P = NS, group A vs group B) with significantly more venous thromboembolic events occurring in patients with low anti-Xa levels (P = .02). Although higher dosing of enoxaparin led to improved anti-Xa levels, this did not equate to a statistical decrease in venous thromboembolism. Copyright © 2013 Elsevier Inc. All rights reserved.

Distinct Signaling Pathways After Higher or Lower Doses of Radiation in Three Closely Related Human Lymphoblast Cell Lines

International Nuclear Information System (INIS)

Lu, T.-P.; Lai, L.-C.; Lin, B.-I.; Chen, L.-H.; Hsiao, T.-H.; Liber, Howard L.; Cook, John A.; Mitchell, James B.; Tsai, M.-H.; Chuang, Eric Y.

2010-01-01

Purpose: The tumor suppressor p53 plays an essential role in cellular responses to DNA damage caused by ionizing radiation; therefore, this study aims to further explore the role that p53 plays at different doses of radiation. Materials and Methods: The global cellular responses to higher-dose (10 Gy) and lower dose (iso-survival dose, i.e., the respective D0 levels) radiation were analyzed using microarrays in three human lymphoblast cell lines with different p53 status: TK6 (wild-type p53), NH32 (p53-null), and WTK1 (mutant p53). Total RNAs were extracted from cells harvested at 0, 1, 3, 6, 9, and 24 h after higher and lower dose radiation exposures. Template-based clustering, hierarchical clustering, and principle component analysis were applied to examine the transcriptional profiles. Results: Differential expression profiles between 10 Gy and iso-survival radiation in cells with different p53 status were observed. Moreover, distinct gene expression patterns were exhibited among these three cells after 10 Gy radiation treatment, but similar transcriptional responses were observed in TK6 and NH32 cells treated with iso-survival radiation. Conclusions: After 10 Gy radiation exposure, the p53 signaling pathway played an important role in TK6, whereas the NFkB signaling pathway appeared to replace the role of p53 in WTK1. In contrast, after iso-survival radiation treatment, E2F4 seemed to play a dominant role independent of p53 status. This study dissected the impacts of p53, NFkB and E2F4 in response to higher or lower doses of γ-irradiation.

Critical group doses arising from routine aquatic discharges of activity from the Heysham 2 nuclear power station

International Nuclear Information System (INIS)

Maul, P.R.

1986-07-01

An assessment of critical group doses arising from routine discharges of activity to sea from the Heysham 2 nuclear power station has been undertaken using the CODAR2 computer program. The largest critical group dose rate was calculated to be 50 μSv/y, about 80 per cent of which arose from the external exposure of individuals occupying intertidal sediments of the Lune Estuary from the single nuclide 60 Co. CODAR2 employs a single well mixed local compartment for critical group calculations and can not include the effects of processes varying over the compartment. A more detailed study of the critical group exposure has been carried out using recently developed methods to assess the uncertainties and pessimisms involved in the CODAR2 calculations. It is concluded that these calculations are pessimistic by about a factor of 2, with a reference calculation using the more detailed methods giving a dose rate of 23 μSv/y for the Lune Estuary group. Further reductions in the dose estimate might be possible if site specific measurements of the concentration factor for Co on estuarine sediments and the sedimentation rate in the Lune Estuary could be made. (author)

Safety and Immunogenicity of Full-Dose Trivalent Inactivated Influenza Vaccine (TIV) Compared With Half-Dose TIV Administered to Children 6 Through 35 Months of Age.

Science.gov (United States)

Halasa, Natasha B; Gerber, Michael A; Berry, Andrea A; Anderson, Edwin L; Winokur, Patricia; Keyserling, Harry; Eckard, Allison Ross; Hill, Heather; Wolff, Mark C; McNeal, Monica M; Edwards, Kathryn M; Bernstein, David I

2015-09-01

Children 6 through 35 months of age are recommended to receive half the dose of influenza vaccine compared with older children and adults. This was a 6-site, randomized 2:1, double-blind study comparing full-dose (0.5 mL) trivalent inactivated influenza vaccine (TIV) with half-dose (0.25 mL) TIV in children 6 through 35 months of age. Children previously immunized with influenza vaccine (primed cohort) received 1 dose, and those with no previous influenza immunizations (naive cohort) received 2 doses of TIV. Local and systemic adverse events were recorded. Sera were collected before immunization and 1 month after last dose of TIV. Hemagglutination inhibition antibody testing was performed. Of the 243 subjects enrolled (32 primed, 211 naive), data for 232 were available for complete analysis. No significant differences in local or systemic reactions were observed. Few significant differences in immunogenicity to the 3 vaccine antigens were noted. The immune response to H1N1 was significantly higher in the full-dose group among primed subjects. In the naive cohort, the geometric mean titer for all 3 antigens after 2 doses of TIV were significantly higher in the 12 through 35 months compared with the 6 through 11 months age group. Our study confirms the safety of full-dose TIV given to children 6 through 35 months of age. An increase in antibody responses after full- versus half-dose TIV was not observed, except for H1N1 in the primed group. Larger studies are needed to clarify the potential for improved immunogenicity with higher vaccine doses. Recommending the same dose could simplify the production, storage, and administration of influenza vaccines.

Higher dose rate Gamma Knife radiosurgery may provide earlier and longer-lasting pain relief for patients with trigeminal neuralgia.

Science.gov (United States)

Lee, John Y K; Sandhu, Sukhmeet; Miller, Denise; Solberg, Timothy; Dorsey, Jay F; Alonso-Basanta, Michelle

2015-10-01

Gamma Knife radiosurgery (GKRS) utilizes cobalt-60 as its radiation source, and thus dose rate varies as the fixed source decays over its half-life of approximately 5.26 years. This natural decay results in increasing treatment times when delivering the same cumulative dose. It is also possible, however, that the biological effective dose may change based on this dose rate even if the total dose is kept constant. Because patients are generally treated in a uniform manner, radiosurgery for trigeminal neuralgia (TN) represents a clinical model whereby biological efficacy can be tested. The authors hypothesized that higher dose rates would result in earlier and more complete pain relief but only if measured with a sensitive pain assessment tool. One hundred thirty-three patients were treated with the Gamma Knife Model 4C unit at a single center by a single neurosurgeon during a single cobalt life cycle from January 2006 to May 2012. All patients were treated with 80 Gy with a single 4-mm isocenter without blocking. Using an output factor of 0.87, dose rates ranged from 1.28 to 2.95 Gy/min. The Brief Pain Inventory (BPI)-Facial was administered before the procedure and at the first follow-up office visit 1 month from the procedure (mean 1.3 months). Phone calls were made to evaluate patients after their procedures as part of a retrospective study. Univariate and multivariate linear regression was performed on several independent variables, including sex, age in deciles, diagnosis, follow-up duration, prior surgery, and dose rate. In the short-term analysis (mean 1.3 months), patients' self-reported pain intensity at its worst was significantly correlated with dose rate on multivariate analysis (p = 0.028). Similarly, patients' self-reported interference with activities of daily living was closely correlated with dose rate on multivariate analysis (p = 0.067). A 1 Gy/min decrease in dose rate resulted in a 17% decrease in pain intensity at its worst and a 22% decrease

Dose-response relationship in locoregional control for patients with stage II-III esophageal cancer treated with concurrent chemotherapy and radiotherapy

International Nuclear Information System (INIS)

Zhang Zhen; Liao Zhongxing; Jin Jing; Ajani, Jaffer; Chang, Joe Y.; Jeter, Melenda; Guerrero, Thomas; Stevens, Craig W.; Swisher, Stephen; Ho, Linus; Yao, James; Allen, Pamela; Cox, James D.; Komaki, Ritsuko

2005-01-01

Purpose: To evaluate the correlation between radiation dose and locoregional control (LRC) for patients with Stage II-III unresectable esophageal cancer treated with concurrent chemotherapy and radiotherapy. Methods and materials: The medical records of 69 consecutive patients with clinical Stage II or III esophageal cancer treated with definitive chemoradiotherapy at the University of Texas M. D. Anderson Cancer Center between 1990 and 1998 were retrospectively reviewed. Of the 69 patients, 43 had received ≤51 Gy (lower dose group) and 26 >51 Gy (higher dose group). The median dose in the lower and higher dose groups was 30 Gy (range, 30-51 Gy) and 59.4 Gy (range, 54-64.8 Gy), respectively. Two fractionation schedules were used: rapid fractionation, delivering 30 Gy at 3 Gy/fraction within 2 weeks, and standard fractionation, delivering ≥45 Gy at 1.8-2 Gy/fraction daily. Total doses of 5% (46.2% vs. 23.3%). The lower dose group had more N1 tumors, but the tumor classification and stage grouping were similar in the two groups. The median follow-up time for all patients was 22 months (range, 2-56 months). Patients in the higher dose group had a statistically significant better 3-year local control rate (36% vs. 19%, p = 0.011), disease-free survival rate (25% vs. 10%, p = 0.004), and overall survival rate (13% vs. 3%, p = 0.054). A trend toward a better distant-metastasis-free survival rate was noted in the higher dose group (72% vs. 59%, p = 0.12). The complete clinical response rate was significantly greater in the higher dose group (46% vs. 23%, p = 0.048). In both groups, the most common type of first failure was persistence of the primary tumor. Significantly fewer patients in the higher dose group had tumor persistence after treatment (p = 0.02). No statistically significant difference was found between the two groups in the pattern of locoregional or distant failure. The long-term side effects of chemoradiotherapy were similar in the two groups, although

Analysis of the Nevada-Applied-Ecology-Group model of transuranic radionuclide transport and dose

International Nuclear Information System (INIS)

Kercher, J.R.; Anspaugh, L.R.

1991-01-01

The authors analyze the model for estimating the dose from 239 Pu developed for the Nevada Applied Ecology Group (NAEG) by using sensitivity analysis and uncertainty analysis. Sensitivity analysis results suggest that the inhalation pathway is the critical pathway for the organs receiving the highest dose. Soil concentration and the factors controlling air concentration are the most important parameters. The only organ whose dose is sensitive to parameters in the ingestion pathway is the GI tract. The inhalation pathway accounts for 100% of the dose to lung, upper respiratory tract and thoracic lymph nodes; and 95% of the dose to liver, bone, kidney and total body. The GI tract receives 99% of its dose via ingestion. Leafy vegetable ingestion accounts for 70% of the dose from the ingestion pathway regardless of organ, peeled vegetables 20%; accidental soil ingestion 5% ingestion of beef liver 4%; beef muscle 1%. Uncertainty analysis indicates that choosing a uniform distribution for the input parameters produces a lognormal distribution of the dose. The ratio of the square root of the variance to the mean is three times greater for the doses than it is for the individual parameters. As found by the sensitivity analysis, the uncertainty analysis suggests that only a few parameters control the dose for each organ. All organs have similar distributions and variance to mean ratios except for the lymph nodes. (author)

[Pretreatment doses of antithymocyte globubin-fresenius for allogeneic hematopoietic stem cell transplantation for beta-thalassemia major].

Science.gov (United States)

Li, Chunfu; Wang, Yanhua; Wu, Xuedong; Pei, Fuyu; He, Yuelin; Feng, Xiaoqin; Liu, Huaying

2012-05-01

To investigate the effects of different doses of antithymocyte globubin-fresenius (ATG-F) for allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with beta-thalassemia Major. Sixty-four children with beta-thalassemia major undergoing allo-HSCT were divided into two equal groups to receive ATG-F pretreatments at high (30 mg/kg) or low (15 mg/kg) doses as part of the conditioning regimen including mainly cyclophosphamide, busulfan, fludarabine, and thiotepa. The outcomes of the patients were compared between the two groups. No obvious difference were noted in the time to leukocyte and platelet engraftment between the two groups. The incidence of grade II-IV acute graft-versus-host disease (aGVHD) appeared to be higher in the low-dose group than in the high-dose group (12.5% vs 9.4%). The incidence of grade III-IV aGVHD was also higher in the low dose group (12.5% vs 6.3%), but the difference was not statistically significant. Application of high-dose ATG-F was associated with a higher rate of probable and possible fungal infection (P<0.05). The two doses of ATG-F is feasible as a part of the conditioning regimen for allo-HSCT in children with beta-thalassemia major.

Weekly, low-dose docetaxel combined with estramustine for Japanese castration-resistant prostate cancer: its efficacy and safety profile compared with tri-weekly standard-dose treatment.

Science.gov (United States)

Nakai, Yasutomo; Nishimura, Kazuo; Nakayama, Masashi; Uemura, Motohide; Takayama, Hitoshi; Nonomura, Norio; Tsujimura, Akira

2014-02-01

We retrospectively investigated the efficacy and safety profile of weekly low-dose docetaxel (DTX) with estramustine in comparison with triweekly standard-dose DTX treatment for Japanese patients with castration-resistant prostate cancer (CRPC). Between April 2002 and January 2011, 75 CRPC patients were treated with triweekly DTX (60-75 mg/m(2) every 3 weeks) (standard-dose group), and 76 CRPC patients were treated with weekly low-dose DTX (20-30 mg/m(2) on days 2 and 9 with estramustine 560 mg on days 1-3 and 8-10) every 3 weeks (low-dose group). Prostate-specific antigen (PSA) response and progression-free and overall survival were analyzed in each group. Median serum PSA level of the standard-dose group and low-dose group was 25.0 and 35.5 ng/ml, respectively. In the standard-dose and low-dose groups, 57.8 and 65.2 % of patients, respectively, achieved a PSA decline ≥ 50 %. There was no significant difference in either median time to progression between the standard-dose group (10.0 months) and low-dose group (7.1 months) or in median duration of survival between the standard-dose group (24.2 months) and low-dose group (30.6 months). Multivariate analysis with a Cox proportional hazards regression model showed that DTX treatment protocol did not influence the risk of death. Incidences of grade 3-4 neutropenia, febrile neutropenia, and thrombocytopenia were significantly higher in the standard-dose versus low-dose group (58.7 vs. 7.9 %, 16.0 vs. 3.9 %, and 8.0 vs. 0 %, respectively). For Japanese CRPC patients, weekly low-dose DTX combined with estramustine has similar efficacy to standard-dose DTX but with fewer adverse events.

Dose measurement, its distribution and individual external dose assessments of inhabitants on high background radiation area in China

Energy Technology Data Exchange (ETDEWEB)

Koga, Taeko; Morishima, Hiroshige [Kinki Univ., Atomic Energy Research Institute, Osaka (Japan); Tatsumi, Kusuo [Kinki Univ., Life Science Research Institute, Osaka (Japan); Nakai, Sayaka; Sugahara, Tsutomu [Health Research Foundation, Kyoto (Japan); Yuan Yongling [Labor Hygiene Institute of Hunan Prov. (China); Wei Luxin [Laboratory of Industorial Hygiene, Ministry of Health (China)

2001-01-01

As a part of the China-Japan cooperative research on the natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external to natural radiation in the high background radiation area (HBRA) of Yangjiang in Guangdong province and in the control area (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by the personal dosimeters, an indirect method was applied to estimate the exposed dose rates from the environmental radiation dose rates measured by survey meters and the occupancy factors of each hamlet. An individual radiation dose roughly correlates with the environmental radiation dose and the life style of the inhabitant. We have analyzed the environmental radiation doses in the hamlets and the variation of the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and the several hamlets of the different level doses in HBRA and Hampizai hamlet in CA. With these parameters, we made estimations of individual dose rates and compared them with those obtained from the direct measurement using dosimeters carried by selected individuals. The results obtained are as follows: (1) The environmental radiation dose rates are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiation. The indoor radiation dose rates were due to the exposure from the natural radioactive nuclides in the building materials and they were about twice higher than the outdoor radiation dose rates. This difference was not observed in CA. (2) The occupancy factor was affected by the age of individuals and the seasons of a year. Indoor occupancy factors were higher for infants and aged individuals than for other age groups. This lead to higher

Dose measurement, its distribution and individual external dose assessments of inhabitants on high background radiation area in China

International Nuclear Information System (INIS)

Koga, Taeko; Morishima, Hiroshige; Tatsumi, Kusuo; Nakai, Sayaka; Sugahara, Tsutomu; Yuan Yongling; Wei Luxin

2001-01-01

As a part of the China-Japan cooperative research on the natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external to natural radiation in the high background radiation area (HBRA) of Yangjiang in Guangdong province and in the control area (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by the personal dosimeters, an indirect method was applied to estimate the exposed dose rates from the environmental radiation dose rates measured by survey meters and the occupancy factors of each hamlet. An individual radiation dose roughly correlates with the environmental radiation dose and the life style of the inhabitant. We have analyzed the environmental radiation doses in the hamlets and the variation of the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and the several hamlets of the different level doses in HBRA and Hampizai hamlet in CA. With these parameters, we made estimations of individual dose rates and compared them with those obtained from the direct measurement using dosimeters carried by selected individuals. The results obtained are as follows: 1) The environmental radiation dose rates are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiation. The indoor radiation dose rates were due to the exposure from the natural radioactive nuclides in the building materials and they were about twice higher than the outdoor radiation dose rates. This difference was not observed in CA. 2) The occupancy factor was affected by the age of individuals and the seasons of a year. Indoor occupancy factors were higher for infants and aged individuals than for other age groups. This lead to higher

Medium doses of daily vitamin D decrease falls and higher doses of daily vitamin D3 increase falls: A randomized clinical trial.

Science.gov (United States)

Smith, Lynette M; Gallagher, J Christopher; Suiter, Corinna

2017-10-01

Falls are a serious health problem in the aging population. Because low levels of vitamin D have been associated with increased fall rates, many trials have been performed with vitamin D; two meta-analyses showed either a small effect or no effect of vitamin D on falls. We conducted a study of the effect of vitamin D on serum 25 hydroxyvitamin D (25OHD) and data on falls was collected as a secondary outcome. In a 12-month double blind randomized placebo trial, elderly women, mean age 66 years, were randomized to one of seven daily oral doses of vitamin D or placebo. The main inclusion criterion for study was a baseline serum 25OHDvitamin D on falls followed a U-shaped curve whether analyzed by dose or serum 25OHD levels. There was no decrease in falls on low vitamin D doses 400, 800 IU, a significant decrease on medium doses 1600, 2400,3200 IU (p=0.020) and no decrease on high doses 4000, 4800 IU compared to placebo (p=0.55). When compared to 12-month serum 25OHD quintiles, the faller rate was 60% in the lowest quintile <25ng/ml (<50nmol/L), 21% in the low middle quintile 32-38ng/ml (80-95nmo/L), 72% in the high middle quintile 38-46ng/ml (95-115nmo/L) and 45% in the highest quintile 46-66ng/ml (115-165nmol/L). In the subgroup with a fall history, fall rates were 68% on low dose, 27% on medium doses and 100% on higher doses. Fall rates on high doses were increased compared to medium doses (Odds Ratio 5.6.95% CI: 2.1-14.8). In summary, the maximum decrease in falls corresponds to a 12- month serum 25OHD of 32-38ng/ml (80-95nmol/L) and faller rates increase as serum 25OHD exceed 40-45ng/ml (100-112.5nmol/L). The Tolerable upper limit (TUL) recently increased in 2010 from 2000 to 4000 IU/day may need to be reduced in elderly women especially in those with a fall history. Copyright © 2017 Elsevier Ltd. All rights reserved.

Report of task group on the biological basis for dose limitation in the skin

International Nuclear Information System (INIS)

1989-08-01

Researchers have drawn attention to what they consider inconsistencies in the manner in which ICRP have considered skin in relation to the effective dose equivalent. They urge that the dose to the skin should be considered routinely for inclusion in the effective dose equivalent in the context of protection of individuals and population groups. They note that even with a weighting factor of only 0.01 that the dose to the skin can be a significant contributor to the effective dose equivalent including skin for practical exposure conditions. In the case of many exposures the risk to the skin can be ignored but exposure in an uniformly contaminated cloud that might occur with 85 Kr the dose to the skin could contribute 60% of the stochastic risk if included in the effective dose equivalent with a W T of 0.01. Through the years and even today the same questions about radiation effects in the skin and dosimetry keep being asked. This report collates the available data and current understanding of radiation effects on the skin, and may make it possible to estimate risks more accurately and to improve the approach to characterizing skin irradiations. 294 refs., 29 figs

Dose titration to reduce dipyridamole-related headache.

Science.gov (United States)

Chang, Yeu-Jhy; Ryu, Shan-Jin; Lee, Tsong-Hai

2006-01-01

Combination of low-dose aspirin and modified-release dipyridamole (ASA+MR-DP) provides a significantly increased benefit in stroke prevention over aspirin alone. However, headaches were reported in more patients receiving dipyridamole-containing agents than in those receiving placebo. We undertook a randomized, double-blind, placebo-controlled trial to evaluate which dosing regimens of ASA+MR-DP have better tolerance. This trial randomized 146 patients with a history of ischemic cerebrovascular disease into three groups: placebo (days 1-28), reduced dose (placebo on days 1-4, ASA+MR-DP once daily before bed during days 5-14, and b.i.d. on days 15-28), and regular dose (placebo on days 1-4, and ASA+MR-DP b.i.d. on days 5-28). Using Chinese diary card, headache was assessed as mean cumulated headache (Sigma frequency x intensity/occurrence days x study days) over the study period, and was graded 0-4 according to Cancer Therapy Evaluation Program, Common Toxicity Criteria, Version 2.0. Intent-to-treat patients after randomization was 46 in placebo group, 45, reduced dose, and 49, regular dose. Among commonly reported adverse effects, headache of any grade occurred significantly more in the regular dose group (38.8%), as compared to the other two groups (p < 0.05). Mean cumulated headache was higher (p < 0.05) in the regular dose group than in the reduced group during days 5-14. Of 27 patients who dropped out, 15 (55.6%) were due to headache, which was substantially more in regular dose (8, 53.3%), though the difference was statistically insignificant. Initial reduced dose treatment with ASA+MR-DP may cause fewer headaches than regular dosing, and seems better tolerated by those susceptible to phosphodiesterase inhibitor-induced headache. Copyright 2006 S. Karger AG, Basel.

Long-Term Results of Fixed High-Dose I-131 Treatment for Toxic Nodular Goiter: Higher Euthyroidism Rates in Geriatric Patients

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Gül Ege Aktaş

2015-10-01

Full Text Available Objective: Geriatric patient population has special importance due to particular challenges. In addition to the increase in incidence of toxic nodular goiter (TNG with age, it has a high incidence in the regions of low-medium iodine intake such as in our country. The aim of this study was to evaluate the overall outcome of high fixed dose radioiodine (RAI therapy, and investigate the particular differences in the geriatric patient population. Methods: One hundred and three TNG patients treated with high dose I-131 (370-740 MBq were retrospectively reviewed. The baseline characteristics; age, gender, scintigraphic patterns and thyroid function tests before and after treatment, as well as follow-up, duration of antithyroid drug (ATD medication and achievement of euthyroid or hypothyroid state were evaluated. The patient population was divided into two groups as those=>65 years and those who were younger, in order to assess the effect of age. Results: Treatment success was 90% with single dose RAI therapy. Hyperthyroidism was treated in 7±7, 2 months after RAI administration. At the end of the first year, overall hypothyroidism rate was 30% and euthyroid state was achieved in 70% of patients. Age was found to be the only statistically significant variable effecting outcome. A higher ratio of euthyroidism was achieved in the geriatric patient population. Conclusion: High fixed dose I-131 treatment should be preferred in geriatric TNG patients in order to treat persistent hyperthyroidism rapidly. The result of this study suggests that high fixed dose RAI therapy is a successful modality in treating TNG, and high rates of euthyroidism can be achieved in geriatric patients.

Assessment of low-dose radiotoxicity in microorganisms and higher organisms

International Nuclear Information System (INIS)

Obeid, Muhammad Hassan

2016-01-01

This work was dedicated to quantify and distinguish the radio- and chemitoxic effects of environmentally relevant low doses of uranium on the metabolism of microorganisms and multicellular organisms by a modern and highly sensitive microcalorimetry. In such low-dose regime, lethality is low or absent. Therefore, quantitative assays based on survival curves cannot be employed, particularly for multicellular organisms. Even in the case of microbial growth, where individual cells may be killed by particle radiation, classical toxicity assessments based on colony counting are not only extremely time-consuming but also highly error-prone. Therefore, measuring the metabolic activity of the organism under such kinds of conditions would give an extremely valuable quantitative measure of viability that is based on life cell monitoring, rather than determining lethality at higher doses and extrapolating it to the low dose regime. The basic concept is simple as it relies on the metabolic heat produced by an organism during development, growth or replication as an inevitable byproduct of all biochemical processes. A metabolic effect in this concept is defined as a change in heat production over time in the presence of a stressor, such as a heavy metal. This approach appeared to be particular versatile for the low dose regime. Thus, the thesis attempted in this case to measure the enthalpy production of a bacterial population as a whole to derive novel toxicity concepts. In the following chapters, an introduction about the properties of ionizing radiation will be briefly presented, in addition to a review about the isothermal calorimetry and its application in studying the bacterial growth. Later in chapter 2, the effect of uranium on the metabolic activity of three different bacterial strains isolated form a uranium mining waste pile together with a reference strain that is genetically related to them will be investigated. Due to the lack of published dedicated calibration

Assessment of low-dose radiotoxicity in microorganisms and higher organisms

Energy Technology Data Exchange (ETDEWEB)

Obeid, Muhammad Hassan

2016-01-11

This work was dedicated to quantify and distinguish the radio- and chemitoxic effects of environmentally relevant low doses of uranium on the metabolism of microorganisms and multicellular organisms by a modern and highly sensitive microcalorimetry. In such low-dose regime, lethality is low or absent. Therefore, quantitative assays based on survival curves cannot be employed, particularly for multicellular organisms. Even in the case of microbial growth, where individual cells may be killed by particle radiation, classical toxicity assessments based on colony counting are not only extremely time-consuming but also highly error-prone. Therefore, measuring the metabolic activity of the organism under such kinds of conditions would give an extremely valuable quantitative measure of viability that is based on life cell monitoring, rather than determining lethality at higher doses and extrapolating it to the low dose regime. The basic concept is simple as it relies on the metabolic heat produced by an organism during development, growth or replication as an inevitable byproduct of all biochemical processes. A metabolic effect in this concept is defined as a change in heat production over time in the presence of a stressor, such as a heavy metal. This approach appeared to be particular versatile for the low dose regime. Thus, the thesis attempted in this case to measure the enthalpy production of a bacterial population as a whole to derive novel toxicity concepts. In the following chapters, an introduction about the properties of ionizing radiation will be briefly presented, in addition to a review about the isothermal calorimetry and its application in studying the bacterial growth. Later in chapter 2, the effect of uranium on the metabolic activity of three different bacterial strains isolated form a uranium mining waste pile together with a reference strain that is genetically related to them will be investigated. Due to the lack of published dedicated calibration

Survey of computed tomography doses in head and chest protocols; Levantamento de doses em tomografia computadorizada em protocolos de cranio e torax

Energy Technology Data Exchange (ETDEWEB)

Souza, Giordana Salvi de; Froner, Ana Paula Pastre; Silva, Ana Maria Marques da, E-mail: giordana.souza@acad.pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Faculdade de Fisica. Nucleo de Pesquisa em Imagens Medicas

2016-07-01

Surveys of dose estimates from different medical imaging modalities highlight significant variations between health care facilities for the same examination and similar patient groups. To ensure that doses are optimized, diagnostic reference levels (DRL) must be determined, allowing the identification of procedures that are out of optimal standards. The aim of this study is to present a retrospective survey of dose indicators in head and chest CT scans, in terms of Dose-Length Product (DLP) and effective dose for adult and pediatric patients, comparing them with DRL in the literature. The study was performed with data from 293 patients submitted to computed tomography of the skull and 146 of the thorax, divided into age groups (0⊣ 1; 1⊣ 5; 5⊣ 10; 10⊣ 15; >15. For head, DLP third percentiles and effective doses are mostly higher than DRL in literature, mainly for children from 10⊣15 years (800 mGy.cm; 3,3 mSv) and 5⊣ 10 years (969 mGy.cm; 2,6 mSv). For thorax examination, although DLP are close to the DRL in literature, high variability is revealed, and the effective doses are higher for all ages. In conclusion, the survey of dose indicators in computed tomography examinations and their comparison with DRL constitute an important tool for the optimization of doses in patients. (author)

Effect of low-dose atropine administration on dobutamine dose requirement in horses anesthetized with detomidine and halothane.

Science.gov (United States)

Weil, A B; Keegan, R D; Greene, S A

1997-12-01

To determine whether a low dose of atropine is associated with decreased requirement for cardiovascular supportive treatment in horses given detomidine prior to maintenance of general anesthesia with halothane. 3 groups of 10 healthy horses. Detomidine (20 micrograms/kg of body weight, i.m.) was administered to all 30 horses. Then, 10 horses received atropine (0.006 mg/kg, i.v.) 1 hour after detomidine administration, 10 horses received atropine (0.012 mg/kg, i.m.) at the time of detomidine administration, and 10 horses served as a control group. Heart rate was measured prior to detomidine administration and at fixed intervals throughout anesthesia. The dobutamine infusion rate necessary to maintain mean arterial blood pressure between 70 and 80 mm of Hg was recorded. Systemic blood pressures, end-tidal halothane, end-tidal CO2, and arterial blood gas tensions were measured at fixed intervals. Mean heart rate was higher among horses receiving atropine i.v. or i.m., compared with that in control horses. Horses that received atropine i.v. had higher systemic arterial blood pressure and required a lower dobutamine infusion rate than did horses of the other groups. Detomidine-treated, halothane-anesthetized horses given atropine i.v. required less dobutamine, compared with horses receiving or not receiving atropine i.m. Complications, such as colic and dysrhythmias, from use of higher doses of atropine, were not observed at this lower dose of atropine. i.v. administration of a low dose of atropine prior to induction of general anesthesia may result in improved blood pressure in horses that have received detomidine before anesthesia with halothane.

Gut microbiota and tacrolimus dosing in kidney transplantation.

Directory of Open Access Journals (Sweden)

John R Lee

Full Text Available Tacrolimus dosing to establish therapeutic levels in recipients of organ transplants is a challenging task because of much interpatient and intrapatient variability in drug absorption, metabolism, and disposition. In view of the reported impact of gut microbial species on drug metabolism, we investigated the relationship between the gut microbiota and tacrolimus dosing requirements in this pilot study of adult kidney transplant recipients. Serial fecal specimens were collected during the first month of transplantation from 19 kidney transplant recipients who either required a 50% increase from initial tacrolimus dosing during the first month of transplantation (Dose Escalation Group, n=5 or did not require such an increase (Dose Stable Group, n=14. We characterized bacterial composition in the fecal specimens by deep sequencing of the PCR amplified 16S rRNA V4-V5 region and we investigated the hypothesis that gut microbial composition is associated with tacrolimus dosing requirements. Initial tacrolimus dosing was similar in the Dose Escalation Group and in the Stable Group (4.2 ± 1.1 mg/day vs. 3.8 ± 0.8 mg/day, respectively, P=0.61, two-way between-group ANOVA using contrasts but became higher in the Dose Escalation Group than in the Dose Stable Group by the end of the first transplantation month (9.6 ± 2.4 mg/day vs. 3.3 ± 1.5 mg/day, respectively, P<0.001. Our systematic characterization of the gut microbial composition identified that fecal Faecalibacterium prausnitzii abundance in the first week of transplantation was 11.8% in the Dose Escalation Group and 0.8% in the Dose Stable Group (P=0.002, Wilcoxon Rank Sum test, P<0.05 after Benjamini-Hochberg correction for multiple hypotheses. Fecal Faecalibacterium prausnitzii abundance in the first week of transplantation was positively correlated with future tacrolimus dosing at 1 month (R=0.57, P=0.01 and had a coefficient ± standard error of 1.0 ± 0.6 (P=0.08 after multivariable linear

Low dose rate and high dose rate intracavitary treatment for cervical cancer

International Nuclear Information System (INIS)

Hareyama, Masato; Oouchi, Atsushi; Shidou, Mitsuo

1997-01-01

From 1984 through 1993, 144 previous untreated patients with carcinoma of uterine cervix were treated with either low dose rate 137 Cs therapy (LDR) or high dose rate 60 Co therapy (HDR). The local failure rates for more than 2-years for the primary lesions were 11.8% (8 of 63 patients) for LDR and 18.0% (11 of 61 patients). Rectal complication rates were significantly lower for HDR versus LDR (14.3% VS. 32.8%. p<0.01). Also, bladder complication rates were significantly lower for HDR versus LDR (0% VS. 10.4%, p<0.005). Treatment results in term of local control were equivalent for HDR and LDR treatment. However, the incidence of complications was higher for the LDR group than for the HDR group. (author)

Optimizing bevacizumab dosing in glioblastoma: less is more.

Science.gov (United States)

Ajlan, Abdulrazag; Thomas, Piia; Albakr, Abdulrahman; Nagpal, Seema; Recht, Lawrence

2017-10-01

Compared to traditional chemotherapies, where dose limiting toxicities represent the maximum possible dose, monoclonal antibody therapies are used at doses well below maximum tolerated dose. However, there has been little effort to ascertain whether there is a submaximal dose at which the efficacy/complication ratio is maximized. Thus, despite the general practice of using Bevacizumab (BEV) at dosages of 10 mg/kg every other week for glioma patients, there has not been much prior work examining whether the relatively high complication rates reported with this agent can be decreased by lowering the dose without impairing efficacy. We assessed charts from 80 patients who received BEV for glioblastoma to survey the incidence of complications relative to BEV dose. All patients were treated with standard upfront chemoradiation. The toxicity was graded based on the NCI CTCAE, version 4.03. The rate of BEV serious related adverse events was 12.5% (n = 10/80). There were no serious adverse events (≥grade 3) when the administered dose was (<3 mg/kg/week), compared to a 21% incidence in those who received higher doses (≥3 mg/kg/week) (P < 0.01). Importantly, the three patient deaths attributable to BEV administration occurred in patients receiving higher doses. Patients who received lower doses also had a better survival rate, although this did not reach statistical significance [median OS 39 for low dose group vs. 17.3 for high dose group (P = 0.07)]. Lower rates of serious BEV related toxicities are noted when lower dosages are used without diminishing positive clinical impact. Further work aimed at optimizing BEV dosage is justified.

Effects of long-term, low dose rate fission neutron irradiation on the peripheral hematological cells in rats

International Nuclear Information System (INIS)

Jiang Dingwen; Lei Chengxiang; Shen Xianrong; Ma Li; Yang Xufang; Peng Wulin; Dai Shourong

2008-01-01

Objective: To evaluate the effects of long-term, low dose rate fission neutron irradiation on the peripheral hematological cells in rats. Methods: 96 rats were randomly divided into the control group and the irradiation group with low dose rate fission neutron ( 252 Cf, 0.35 mGy/h) irradiation 20.5 h every day. 8 rats of each group were killed at 14 d, 28 d, 42d, 56d, 70d after irradiation and 35d after the irradiation, and their peripheral hematological cells were tested respectively. Results: Compared with the control group, peripheral blood WBC was reduced significantly at the dose of 0.3Gy and 0.4Gy (P < 0.05), and was reduced remarkably at dose of 0.5Gy (P<0.01) and 35d after stopping irradiation(P<0.01). At dose of 0.2Gy, Peripheral blood RBC was abnormally higher comparing with the control group (P<0.01), accompanying with higher HCT and HGB, which suggests condensed blood. At the other point, RBC tend to become lower, but only at dose 0.5Gy, and the difference is significant comparing with control group(P <0.05). At dose of 0.3Gy, 0.4Gy and 0.5Gy, HCT were significantly lower comparing with control group. Comparing with control group, MCV was higher at 35d after stopping irradiation, and PLT was significantly lower in dose of 0.2Gy. Conclusion: Long-term irradiation with low dose rate fission neutron could significantly reduce peripheral blood WBC, with less effects on RBC and PLT. The reduced WBC could not recover at 35d after stopping irradiation. (authors)

Broader Considerations of Higher Doses of Donepezil in the Treatment of Mild, Moderate, and Severe Alzheimer's Disease

Directory of Open Access Journals (Sweden)

Camryn Berk

2012-01-01

Full Text Available Donepezil, a highly selective acetylcholinesterase inhibitor (AChEI, is approved as a symptomatic treatment mild, moderate, and severe Alzheimer's disease (AD. Donepezil exerts its treatment effect through multiple mechanisms of action including nicotinic receptor stimulation, mitigation of excitotoxicity, and influencing APP processing. The use of donepezil at higher doses is justified given the worsening cholinergic deficit as the disease advances. Donepezil has been investigated in several clinical trials of subjects with moderate-to-severe AD. While the side effects are class specific (cholinergically driven, demonstrable benefit has been shown at the 10 mg dose and the 23 mg doses. Here, we review the clinical justification, efficacy, safety, and tolerability of use of donepezil in the treatment of moderate-to-severe AD.

Comparison of microdose flare-up and antagonist multiple-dose protocols for poor-responder patients: a randomized study.

Science.gov (United States)

Demirol, Aygul; Gurgan, Timur

2009-08-01

To compare the efficacy of the microdose flare-up and multiple-dose antagonist protocols for poor-responder patients in intracytoplasmic sperm injection-ET cycles. A randomized, prospective study. Center for assisted reproductive technology in Turkey. Ninety patients with poor ovarian response in a minimum of two previous IVF cycles. All women were prospectively randomized into two groups by computer-assisted randomization. The patients in group 1 were stimulated according to the microdose flare-up protocol (n = 45), while the patients in group 2 were stimulated according to antagonist multiple-dose protocol (n = 45). The mean number of mature oocytes retrieved was the primary outcome measure, and fertilization rate, implantation rate per embryo, and clinical pregnancy rates were secondary outcome measures. The mean age of the women, the mean duration of infertility, basal FSH level, and the number of previous IVF cycles were similar in both groups. The total gonadotropin dose used was significantly higher in group 2, while the number of oocytes retrieved was significantly greater in group 1. Although the fertilization and clinical pregnancy rates were nonsignificantly higher in group 1 compared with group 2, the implantation rate was significantly higher in the microdose flare-up group than in the multiple-dose antagonist group (22% vs. 11%). The microdose flare-up protocol seems to have a better outcome in poor-responder patients, with a significantly higher mean number of mature oocytes retrieved and higher implantation rate.

Learning Groups in MOOCs: Lessons for Online Learning in Higher Education

Directory of Open Access Journals (Sweden)

Godfrey Mayende

2017-06-01

Full Text Available when there is interaction within online learning groups, meaningful learning is achieved. Motivating and sustaining effective student interactions requires planning, coordination and implementation of curriculum, pedagogy and technology. For our aim to understand online learning group processes to identify effective online learning group mechanisms, comparative analysis was used on a massive open online course (MOOC run in 2015 and 2016. Qualitative (interaction on the platform and quantitative (survey methods were used. The findings revealed several possible ways to improve online learning group processes. This paper concludes that course organization helped in increasing individual participation in the groups. Motivation by peers helped to increase sustainability of interaction in the learning groups. Applying these mechanisms in higher education can make online learning groups more effective.

Dose sculpting with generalized equivalent uniform dose

International Nuclear Information System (INIS)

Wu Qiuwen; Djajaputra, David; Liu, Helen H.; Dong Lei; Mohan, Radhe; Wu, Yan

2005-01-01

With intensity-modulated radiotherapy (IMRT), a variety of user-defined dose distribution can be produced using inverse planning. The generalized equivalent uniform dose (gEUD) has been used in IMRT optimization as an alternative objective function to the conventional dose-volume-based criteria. The purpose of this study was to investigate the effectiveness of gEUD optimization to fine tune the dose distributions of IMRT plans. We analyzed the effect of gEUD-based optimization parameters on plan quality. The objective was to determine whether dose distribution to selected structures could be improved using gEUD optimization without adversely altering the doses delivered to other structures, as in sculpting. We hypothesized that by carefully defining gEUD parameters (EUD 0 and n) based on the current dose distributions, the optimization system could be instructed to search for alternative solutions in the neighborhood, and we could maintain the dose distributions for structures already satisfactory and improve dose for structures that need enhancement. We started with an already acceptable IMRT plan optimized with any objective function. The dose distribution was analyzed first. For structures that dose should not be changed, a higher value of n was used and EUD 0 was set slightly higher/lower than the EUD value at the current dose distribution for critical structures/targets. For structures that needed improvement in dose, a higher to medium value of n was used, and EUD 0 was set to the EUD value or slightly lower/higher for the critical structure/target at the current dose distribution. We evaluated this method in one clinical case each of head and neck, lung and prostate cancer. Dose volume histograms, isodose distributions, and relevant tolerance doses for critical structures were used for the assessment. We found that by adjusting gEUD optimization parameters, the dose distribution could be improved with only a few iterations. A larger value of n could lead to

Factors associated with higher oxytocin requirements in labor.

Science.gov (United States)

Frey, Heather A; Tuuli, Methodius G; England, Sarah K; Roehl, Kimberly A; Odibo, Anthony O; Macones, George A; Cahill, Alison G

2015-09-01

To identify clinical characteristics associated with high maximum oxytocin doses in women who achieve complete cervical dilation. A retrospective nested case-control study was performed within a cohort of all term women at a single center between 2004 and 2008 who reached the second stage of labor. Cases were defined as women who had a maximum oxytocin dose during labor >20 mu/min, while women in the control group had a maximum oxytocin dose during labor of ≤20 mu/min. Exclusion criteria included no oxytocin administration during labor, multiple gestations, major fetal anomalies, nonvertex presentation, and prior cesarean delivery. Multiple maternal, fetal, and labor factors were evaluated with univariable analysis and multivariable logistic regression. Maximum oxytocin doses >20 mu/min were administered to 108 women (3.6%), while 2864 women received doses ≤20 mu/min. Factors associated with higher maximum oxytocin dose after adjusting for relevant confounders included maternal diabetes, birthweight >4000 g, intrapartum fever, administration of magnesium, and induction of labor. Few women who achieve complete cervical dilation require high doses of oxytocin. We identified maternal, fetal and labor factors that characterize this group of parturients.

Safety and pharmacokinetics of single and multiple intravenous bolus doses of diclofenac sodium compared with oral diclofenac potassium 50 mg: A randomized, parallel-group, single-center study in healthy subjects.

Science.gov (United States)

Munjal, Sagar; Gautam, Anirudh; Okumu, Franklin; McDowell, James; Allenby, Kent

2016-01-01

In a randomized, parallel-group, single-center study in 42 healthy adults, the safety and pharmacokinetic parameters of an intravenous formulation of 18.75 and 37.5 mg diclofenac sodium (DFP-08) following single- and multiple-dose bolus administration were compared with diclofenac potassium 50 mg oral tablets. Mean AUC0-inf values for a 50-mg oral tablet and an 18.75-mg intravenous formulation were similar (1308.9 [393.0]) vs 1232.4 [147.6]). As measured by the AUC, DFP-08 18.75 mg and 37.5 mg demonstrated dose proportionality for extent of exposure. One subject in each of the placebo and DFP-08 18.75-mg groups and 2 subjects in the DFP-08 37.5-mg group reported adverse events that were considered by the investigator to be related to the study drug. All were mild in intensity and did not require treatment. Two subjects in the placebo group and 1 subject in the DFP-08 18.75-mg group reported grade 1 thrombophlebitis; no subjects reported higher than grade 1 thrombophlebitis after receiving a single intravenous dose. The 18.75- and 37.5-mg doses of intravenous diclofenac (single and multiple) were well tolerated for 7 days. Additional efficacy and safety studies are required to fully characterize the product. © 2015, The American College of Clinical Pharmacology.

Report of the Nuclear Energy Agency expert group on gut transfer factors: implications for dose per unit intake

International Nuclear Information System (INIS)

1988-01-01

This note describes the gut transfer factors recommended by an Expert Group of the Nuclear Energy Agency for intakes of certain important elements in food and drinking water. The evidence behind the recommendations is discussed and their implications for dose per unit intake is investigated. It is found that in many cases the dose per unit intake calculated using the gut uptake factor recommended by the Expert Group is similar to that calculated using the recommendations of ICRP Publication 30. However, in some cases there are substantial increases in dose per unit intake. The largest increases are by a factor of fifty for intakes of certain thorium isotopes by infants. (author)

Adaptive grouping for the higher-order multilevel fast multipole method

DEFF Research Database (Denmark)

Borries, Oscar Peter; Jørgensen, Erik; Meincke, Peter

2014-01-01

An alternative parameter-free adaptive approach for the grouping of the basis function patterns in the multilevel fast multipole method is presented, yielding significant memory savings compared to the traditional Octree grouping for most discretizations, particularly when using higher-order basis...... functions. Results from both a uniformly and nonuniformly meshed scatterer are presented, showing how the technique is worthwhile even for regular meshes, and demonstrating that there is no loss of accuracy in spite of the large reduction in memory requirements and the relatively low computational cost....

Daptomycin versus linezolid for the treatment of vancomycin-resistant enterococcal bacteraemia: implications of daptomycin dose.

Science.gov (United States)

Chuang, Y-C; Lin, H-Y; Chen, P-Y; Lin, C-Y; Wang, J-T; Chang, S-C

2016-10-01

Treatment options for vancomycin-resistant enterococci (VRE) bloodstream infection are limited. Studies comparing daptomycin or linezolid in treating VRE bloodstream infection have conflicting results and suggest daptomycin underdosing. The responses to different daptomycin doses have not been studied. We conducted a multicentre prospective cohort study to compare linezolid and daptomycin (≥6 mg/kg) for the treatment of VRE bloodstream infection. The primary outcome was 14-day mortality. We used multivariate logistic regression analysis for outcome analysis and a generalized additive model for dose-dependent response estimation. Two hundred twelve patients were included (daptomycin, n = 141; linezolid, n = 71). All-cause 14-day mortality was higher in the daptomycin group (36.9% vs. 21.1%; p 0.03). After adjusting for confounders in logistic regression, mortality was lower in the linezolid group (adjusted odds ratio (aOR), 0.45; 95% confidence interval (CI), 0.21-0.96; p 0.04). The generalized additive model showed that higher-dose daptomycin (≥9 mg/kg) was associated with better survival than lower-dose daptomycin (6-9 mg/kg). Logistic regression showed that linezolid (aOR, 0.36; 95% CI, 0.17-0.79; p 0.01) and higher-dose daptomycin (aOR, 0.26; 95% CI, 0.09-0.74; p 0.01) independently predicted lower mortality compared to lower-dose daptomycin. Linezolid was not superior to higher-dose daptomycin in terms of mortality (aOR, 1.40; 95% CI, 0.45-4.37; p 0.57). Higher-dose daptomycin had lower mortality than lower-dose daptomycin. Despite higher mortality for lower-dose daptomycin than linezolid, linezolid conferred no survival benefit compared to higher-dose daptomycin. Our findings suggest that the recommended daptomycin dose is suboptimal for treating VRE bacteraemia. Copyright © 2016. Published by Elsevier Ltd.

Web Environments for Group-Based Project Work in Higher Education

NARCIS (Netherlands)

Andernach, J.A.; van Diepen, N.M.; Collis, Betty; Andernach, Toine

1997-01-01

We discuss problems confronting the use of group-based project work as an instructional strategy in higher education and describe two courses in which course-specific World Wide Web (Web) environments have evolved over a series of course sequences and are used both as tool environments for

Effect of Two Different Doses of Dexmedetomidine on Stress Response in Laparoscopic Pyeloplasty: A Randomized Prospective Controlled Study.

Science.gov (United States)

Shamim, Rafat; Srivastava, Shashi; Rastogi, Amit; Kishore, Kamal; Srivastava, Aneesh

2017-01-01

Clonidine, opioids, β-blockers, and dexmedetomidine have been tried to attenuate stress responses during laparoscopic surgery. We evaluated the efficacy of dexmedetomidine in two different doses in attenuating stress responses on patients undergoing laparoscopic pyeloplasty. Ninety patients were assigned to one of the three groups: Group A, Group B, and Group C. Group B received dexmedetomidine 1 mcg/kg as loading dose, followed by 0.7 mcg/kg/h for maintenance; Group C received dexmedetomidine 0.7 mcg/kg as a loading dose, followed by 0.5 mcg/kg/h for maintenance. Group A received normal saline. Stress responses were assessed by the variations in heart rate (HR), mean arterial pressure (MAP), blood glucose levels, and serum cortisol levels. One-way analysis of variance test was applied. Multiple comparisons between groups were done with post hoc Bonferroni test. The HR and MAP were found to be higher in Group A. The difference was statistically significant ( P < 0.05) during intubation, carbon dioxide insufflation, and extubation when compared with Groups B and C. Blood glucose levels at postintubation and at extubation were higher in Group A and statistically significant ( P < 0.05) when compared with Groups B and C. Serum cortisol levels at postintubation, during midsurgery, and 2 h after extubation were higher in Group A and statistically significant ( P < 0.05) when compared with Groups B and C. However, HR, MAP, blood glucose levels, and serum cortisol levels were similar in dexmedetomidine groups. Dexmedetomidine decreases stress response and provides good condition for maintenance of anesthesia. Dexmedetomidine when used in lower dose in Group C decreases stress response comparable to higher dose in Group B.

Biosphere Dose Conversion Factors for Reasonably Maximally Exposed Individual and Average Member of Critical Group

International Nuclear Information System (INIS)

K. Montague

2000-01-01

The purpose of this calculation is to develop additional Biosphere Dose Conversion Factors (BDCFs) for a reasonably maximally exposed individual (RMEI) for the periods 10,000 years and 1,000,000 years after the repository closure. In addition, Biosphere Dose Conversion Factors for the average member of a critical group are calculated for those additional radionuclides postulated to reach the environment during the period after 10,000 years and up to 1,000,000 years. After the permanent closure of the repository, the engineered systems within the repository will eventually lose their abilities to contain radionuclide inventory, and the radionuclides will migrate through the geosphere and eventually enter the local water table moving toward inhabited areas. The primary release scenario is a groundwater well used for drinking water supply and irrigation, and this calculation takes these postulated releases and follows them through various pathways until they result in a dose to either a member of critical group or a reasonably maximally exposed individual. The pathways considered in this calculation include inhalation, ingestion, and direct exposure

Sun-Induced Changes in Stratum Corneum Function Are Gender and Dose Dependent in a Chinese Population

Science.gov (United States)

Liu, Z.; Fluhr, J.W.; Song, S.P.; Sun, Z.; Wang, H.; Shi, Y.J.; Elias, P.M.; Man, M.-Q.

2010-01-01

Previous studies have demonstrated that UVB radiation changes the epidermal permeability barrier and stratum corneum (SC) hydration. It is well known that sun exposure causes erythema, sunburn and melanoma. However, whether daily sun exposure alters SC integrity and epidermal permeability barrier function is largely unknown, especially in Chinese subjects. In the present study, we assess the SC integrity, SC hydration and epidermal permeability barrier function following various doses of sun exposure. A total of 258 subjects (124 males and 134 females) aged 18–50 years were enrolled. A multifunctional skin physiology monitor (Courage & Khazaka MPA5) was used to measure SC hydration and transepidermal water loss (TEWL) on the forearms. In males, basal TEWL was higher with higher doses of sun exposure than with lower doses and control, whereas in females, basal TEWL was higher with lower doses of sun exposure than with higher doses and control. In the group with higher doses of sun exposure, TEWL in females was significantly lower than that in males. The barrier recovery was faster in females than in males in both control and lower-dose groups. In both males and females, barrier recovery was delayed with higher doses of sun exposure. In males, sun exposure did not alter SC hydration, while in females SC hydration was lower with lower doses of sun exposure as compared with control and higher doses of sun exposure. These results demonstrated that sun-induced changes in SC function and SC hydration vary with gender and the extent of sun exposure. PMID:20571289

Occupational radiation dose in Indonesia 1981-1986

International Nuclear Information System (INIS)

Hiswara, E.; Ismono, A.

1993-01-01

Occupational radiation dose in Indonesia 1981-1986. This paper presents the occupational radiation dose in Indonesia during the period of 1981-1986. The highest collective dose accurated in 1983 was calculated to be 2.68 man-Sv, with the maximum mean dose per worker, who received dose more than zero, was around 11.07 mSv in the same year. In 1985, a relative collective dose from medical occupations of 1.88 man mSv for 10 6 population was estimated based on its total collective dose of 0.31 man-mSv. The total number of workers who received annual collective dose less than 5 mSv varied from 97.0% in 1981 to 99.5% in 1986. As a group, the industrial occupations has considerably higher risk in receiving a dose than others. (authors). 11 refs., 7 tabs

Oligodendroglial response to ionizing radiation: Dose and dose-rate response

International Nuclear Information System (INIS)

Levy, R.P.

1991-01-01

An in vitro system using neuroglia from neonatal rat brain was developed to examining the morphologic, immunocytochemical and biochemical response of oligodendroglia to ionizing radiation. Following acute γ-radiation at day-in-culture (DIC) 8, oligodendrocyte counts at DIC 14 were 55% to 65% of control values after 2 Gy, and 29% to 36% after 5 Gy. Counts increased to near-normal levels at DIC 21 in the 2 Gy group and to 75% of normal in the 5 Gy group. Myelin basic protein levels (MBP) at DIC 14 were 60% of control values after 2 Gy, and 40% after 5 Gy. At DIC 21, MBP after 2 Gy was 45% greater than that observed at DIC 14, but MBP, as a fraction of age-matched control values, dropped from 60% to 50%. Following 5 Gy, absolute MBP changed little between DIC 14 and DIC 21, but decreased from 40% to 25% of control cultures. It was concluded that oligodendrocytes in irradiated cultures had significantly lower functional capacity than did unirradiated controls. The response to split-dose irradiation indicated that nearly all sublethal damage in the oligodendrocyte population (and its precursors) was repaired within 3 h to 4 h. At DIC 14, the group irradiated in a single fraction had significantly lower oligodendrocyte counts than any group given split doses; all irradiated cultures had marked depression of MBP synthesis, but to significant differences referable to time interval between doses. At DIC 21, cultures irradiated at intervals of 0 h to 2 h had similar oligodendrocyte counts to one another, but these counts were significantly lower than in cultures irradiated at intervals of 4 h to 6 h; MBP levels remained depressed at DIC 21 for all irradiated cultures. The oligodendrocyte response to dose rate (0.03 to 1.97 Gy/min) was evaluated at DIC 14 and DIC 21. Exposure at 0.03 Gy/min suppressed oligodendrocyte counts at DIC 21 less than did higher dose rates in 5-Gy irradiated cultures

The gonad dose produced by a 60Co irradiation of peripheral, interpleural, and retroperitoneal lymph node groups

International Nuclear Information System (INIS)

Hassenstein, E.; Nuesslin, F.; Medizinische Hochschule Hannover

1976-01-01

A telecobalt therapy of lymph node groups was simulated on the Alderson phantom and the gonad dose caused by each irradiation field was measured with LiF dosimeters. When the supradiaphragmatic and the para-aortal lymph nodes were irradiated, the ovary dose showed rates up to 20 per thousand of the dose maximum. The irradiation of the same zones brought about a testicle dose of less than 5 per thousand of the dose maximum, and only 1/20 of this rate was achieved when a lead plate of about four cm was used in order to protect the testicles. The results are discussed under the point of view of the genetic risk. (orig.) [de

The effect of low-dose neutron irradiation on extracellular matrix

International Nuclear Information System (INIS)

Chen Tiehe; Lu Yongjie; Chai Mingsheng; Peng Wulin; Yang Yifang; Pan Yan; Chen Jinguo

2003-01-01

Projective: To study the effect of neutron irradiation on extracellular matrix. Methods: 120 male wistar rats were divided into four groups at random, and then exposed to neutron of 252 Cf-source at the doses of 0, 0.29, 0.62 and 1.20 Gy, respectively. After the exposure of 3 days, 1 month and 2 months, the rats were sacrificed and lung tissue specimens stored at -30 degree C. Hyaluronan, laminin, type III procollagen and type IV collagen in the lung tissue were detected by the method of radioimmunoassay. Results: The differences of the levels of hyaluronan in lung tissue among the groups were unsignificant. The levels of laminin in 0.29, 0.62 and 1.20 Gy groups after the 3-day exposure were remarkably different to those of the control group, and unable to recover completely even 2 months after the exposure. The levels of type IV collagen in higher three irradiated groups were all higher, but not significantly. The levels of type III procollagen in the early stage after exposure were higher, and later they lowered. Conclusion: The levels of some components of extracellular matrix in the lung tissue of rat can be changed by low-dose of neutron irradiation, but their variational modes and degrees depend on the dose of neutron irradiation and the length of period after exposure

Influence of control group therapy on the benefit from dose-dense chemotherapy in early breast cancer: a systemic review and meta-analysis.

Science.gov (United States)

Goldvaser, Hadar; Majeed, Habeeb; Ribnikar, Domen; Šeruga, Boštjan; Ocaña, Alberto; Cescon, David W; Amir, Eitan

2018-02-08

Results from clinical trials of adjuvant dose-dense chemotherapy in patients with breast cancer are inconsistent. A systematic search of MEDLINE identified studies comparing the efficacy of dose-dense adjuvant chemotherapy to a standard treatment. The primary analysis included studies that used identical regimens in the experimental and control groups, but varied only dose density. A secondary analysis included studies that used either different drugs or doses in the experimental and the control groups. Hazard ratios (HRs) and 95% confidence intervals were computed for disease-free survival (DFS) and overall survival (OS) and pooled in a meta-analysis. Subgroup analyses and meta-regression explored drug schedules utilized in control groups and the influence of clinicopathologic variables on benefit from dose-dense therapy. The primary analysis included 5 studies comprising 9819 patients while the secondary analysis included 6 studies comprising 9679 patients. Dose-dense treatment significantly improved DFS (HR 0.85, p benefit was observed in pre-menopausal women and those with nodal involvement, but there was no influence of hormone receptor status on results. Adjuvant dose-dense regimens improve breast cancer outcomes. It remains uncertain whether the observed benefit reflects the impact of dose density or the inferiority of paclitaxel every 3 weeks as a control group.

Dose sparing of induction dose of propofol by fentanyl and butorphanol: A comparison based on entropy analysis

Directory of Open Access Journals (Sweden)

Jasleen Kaur

2013-01-01

Full Text Available Background: The induction dose of propofol is reduced with concomitant use of opioids as a result of a possible synergistic action. Aim and Objectives: The present study compared the effect of fentanyl and two doses of butorphanol pre-treatment on the induction dose of propofol, with specific emphasis on entropy. Methods: Three groups of 40 patients each, of the American Society of Anaesthesiologistsphysical status I and II, were randomized to receive fentanyl 2 μg/kg (Group F, butorphanol 20 μg/kg (Group B 20 or 40 μg/kg (Group B 40 as pre-treatment. Five minutes later, the degree of sedation was assessed by the observer′s assessment of alertness scale (OAA/S. Induction of anesthesia was done with propofol (30 mg/10 s till the loss of response to verbal commands. Thereafter, rocuronium 1 mg/kg was administered and endotracheal intubation was performed 2 min later. OAA/S, propofol induction dose, heart rate, blood pressure, oxygen saturation and entropy (response and state were compared in the three groups. Statistical Analysis: Data was analyzed using ANOVA test with posthoc significance, Kruskal-Wallis test, Chi-square test and Fischer exact test. A P<0.05 was considered as significant. Results: The induction dose of propofol (mg/kg was observed to be 1.1±0.50 in Group F, 1.05±0.35 in Group B 20 and 1.18±0.41 in Group B40. Induction with propofol occurred at higher entropy values on pre-treatment with both fentanyl as well as butorphanol. Hemodynamic variables were comparable in all the three groups. Conclusion: Butorphanol 20 μg/kg and 40 μg/kg reduce the induction requirement of propofol, comparable to that of fentanyl 2 μg/kg, and confer hemodynamic stability at induction and intubation.

Dose measurement, its distribution and individual external dose assessments of inhabitants in the high background radiation areas in China

International Nuclear Information System (INIS)

Morishima, Hiroshige; Koga, Taeko; Tatsumi, Kusuo; Nakai, Sayaka; Sugahara, Tsutomu; Yuan Yongling; Wei Luxin

2000-01-01

As a part of the China-Japan cooperative research on natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external exposure to natural radiation in the high background radiation areas (HBRA) of Yangjiang in Guangdong province and in the control areas (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by personal dosimeters, an indirect method was applied in which the exposed individual doses were estimated from the environmental radiation doses measured by survey meters and the occupancy factors of each hamlet. We analyzed the dose in the hamlets and the variation in the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and several hamlets of different dose levels in HBRA and Hampizai hamlet in CA. With these parameters, we estimated individual dose rates and compared them with those obtained from direct measurement using dosimeters carried by selected individuals. The results obtained are as follows. The environmental radiation doses are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiations. The indoor radiation doses were due to exposure from the natural radioactive nuclides in the building materials and were about two times as large as the outdoor radiation doses. The difference between indoor and outdoor doses was not observed in CA. The occupancy factor was influenced by the age of individuals and by the season of the year. The occupancy factor was higher for infants and aged individuals than for other age groups. This lead to higher dose rates of exposure to those age groups. A good correlation was observed between the dose assessed indirectly and that measured directly and the

Dose measurement, its distribution and individual external dose assessments of inhabitants in the high background radiation areas in China

Energy Technology Data Exchange (ETDEWEB)

Morishima, Hiroshige; Koga, Taeko [Kinki Univ., Higashi-Osaka, Osaka (Japan). Atomic Energy Research Inst.; Tatsumi, Kusuo; Nakai, Sayaka; Sugahara, Tsutomu; Yuan Yongling; Wei Luxin

2000-10-01

As a part of the China-Japan cooperative research on natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external exposure to natural radiation in the high background radiation areas (HBRA) of Yangjiang in Guangdong province and in the control areas (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by personal dosimeters, an indirect method was applied in which the exposed individual doses were estimated from the environmental radiation doses measured by survey meters and the occupancy factors of each hamlet. We analyzed the dose in the hamlets and the variation in the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and several hamlets of different dose levels in HBRA and Hampizai hamlet in CA. With these parameters, we estimated individual dose rates and compared them with those obtained from direct measurement using dosimeters carried by selected individuals. The results obtained are as follows. The environmental radiation doses are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiations. The indoor radiation doses were due to exposure from the natural radioactive nuclides in the building materials and were about two times as large as the outdoor radiation doses. The difference between indoor and outdoor doses was not observed in CA. The occupancy factor was influenced by the age of individuals and by the season of the year. The occupancy factor was higher for infants and aged individuals than for other age groups. This lead to higher dose rates of exposure to those age groups. A good correlation was observed between the dose assessed indirectly and that measured directly and the

Dose escalation with 3-D CRT in prostate cancer: five year dose responses and optimal treatment

International Nuclear Information System (INIS)

Hanks, Gerald; Hanlon, Alexandra; Pinover, Wayne; Hunt, Margie; Movsas, Benjamin; Schultheiss, Timothy

1997-01-01

studies. (1) There is little advantage to be gained from dose levels above 75-76 Gy for the PSA grouping 10-19.9 ng/ml as 5 yr bNED at that dose is 80%. It is possible, however, that local failure between 5 and 10 yrs may be improved by higher dose and it may be worthwhile to investigate 80 Gy in these patients. (2) Optimal dose level for the pretreatment PSA 20+ ng/ml group is not defined by observed dose response but the logit plot strongly suggests dose levels of ≥80 Gy should be investigated. The 5 yr bNED rate observed in our study at 76 Gy is ∼33% and less than satisfactory. The dose of 70 Gy commonly given in the U.S. with conventional treatment will result in ∼ 15% bNED at 5 yrs and is clearly inadequate. It is possible that the problem of high rates of failure in patients with pretreatment PSA 20+ ng/ml can be improved by higher dose as the pattern of failure for these patients treated to ∼76 Gy shows 60% have slowly rising PSA levels suggesting local failure, while 40% have rapidly rising PSA levels, and metastasis. This possibility needs further study. With longer follow-up and 5 yr actuarial rates of morbidity, the slopes of grade 2 GU and grade 3,4 GI morbidity have become more shallow, 4% and 12% respectively. Grade 2 GI morbidity which is largely rectal bleeding, however, remains steep (23%). With the technique used, morbidity at 76 Gy is grade 2 GI 40%, grade 3,4 GI 8%, Grade 2 GU 12%. Morbidity at 80 Gy is grade 2 GI 61%, grade 3,4 GI 12%, and grade 2 GU 13%. We currently limit dose to 71-72 Gy to the anterior rectal wall, and have previously demonstrated that grade 2 and 3,4 GI morbidity is favorably influenced by this change

Is It All about the Higher Dose? Why Psychoanalytic Therapy Is an Effective Treatment for Major Depression.

Science.gov (United States)

Zimmermann, Johannes; Löffler-Stastka, Henriette; Huber, Dorothea; Klug, Günther; Alhabbo, Sarah; Bock, Astrid; Benecke, Cord

2015-01-01

Empirical evidence for the effectiveness of long-term psychodynamic psychotherapy (LTPP) in patients with mood disorders is growing. However, it is unclear whether the effectiveness of LTPP is due to distinctive features of psychodynamic/psychoanalytic techniques or to a higher number of sessions. We tested these rival hypotheses in a quasi-experimental study comparing psychoanalytic therapy (i.e., high-dose LTPP) with psychodynamic therapy (i.e., low-dose LTPP) and cognitive-behavioural therapy (CBT) for depression. Analyses were based on a subsample of 77 subjects, with 27 receiving psychoanalytic therapy, 26 receiving psychodynamic therapy and 24 receiving CBT. Depressive symptoms, interpersonal problems and introject affiliation were assessed prior to treatment, after treatment and at the 1-, 2- and 3-year follow-ups. Psychoanalytic techniques were assessed from three audiotaped middle sessions per treatment using the Psychotherapy Process Q-Set. Subjects receiving psychoanalytic therapy reported having fewer interpersonal problems, treated themselves in a more affiliative way directly after treatment and tended to improve in depressive symptoms and interpersonal problems during follow-up as compared with patients receiving psychodynamic therapy and/or CBT. Multilevel mediation analyses suggested that post-treatment differences in interpersonal problems and introject affiliation were mediated by the higher number of sessions, and follow-up differences in depressive symptoms were mediated by the more pronounced application of psychoanalytic techniques. We also found some evidence for indirect treatment effects via psychoanalytic techniques on changes in introject affiliation during follow-up. These results provide support for the prediction that both a high dose and the application of psychoanalytic techniques facilitate therapeutic change in patients with major depression. Psychoanalytic therapy is an effective treatment for major depression, especially in the

Ultra-low dose of intravitreal bevacizumab in retinopathy of prematurity.

Science.gov (United States)

Şahin, A; Gürsel-Özkurt, Z; Şahin, M; Türkcü, F M; Yıldırım, A; Yüksel, H

2018-05-01

We aimed to investigate the effectivity of the 0.0625 mg dose of bevacizumab in patients with retinopathy of prematurity (ROP) and compare the results with 0.625 mg dose of intravitreal bevacizumab (IVB) injection. The medical records of the patients with type 1 ROP who received IVB monotherapy were retrospectively reviewed. Demographic and clinical characteristics of the patients were recorded. The patients were classified into two groups with respect to received dose of bevacizumab as follows: group F (n = 46) (full dose of bevacizumab-0.625 mg/0.025 ml) and group L (n = 45) (low dose (one tenth) of bevacizumab-0.0625 mg/0.025 ml). Both treatment dose regimens have similar outcomes. Moreover, the mean retinal vascularization time seemed to be significantly higher in group F compared to group L, 168 ± 65 and 97 ± 29 days, respectively (p < 0.001). Disappearance of plus sign is observed earlier in group F (2.45 ± 1.7 vs 3.66 ± 2.46 days, respectively, p = 0.03). The low dose (0.0625 mg) of IVB treatment was effective as full (0.625 mg) dose in ROP treatment. Moreover, our results showed that low-dose treatment might provide faster retinal vascularization than the regular used dose. On the other hand, disappearance of the plus sign takes longer time in patients treated with low dose compared to eyes treated with full dose of IVB that should be taken into account.

Peer Group Mentoring Programmes in Finnish Higher Education--Mentors' Perspectives

Science.gov (United States)

Skaniakos, Terhi; Penttinen, Leena; Lairio, Marjatta

2014-01-01

Peer mentoring is one of the most important guidance practices for first-year students entering higher education and academic life. We are interested in mentors' roles and apply the ideas of group counseling in order to increase the understanding of peer mentoring. Other aspects of guidance--content, methods, and collaboration--are approached on…

Research on low radiation doses - A better understanding of low doses

International Nuclear Information System (INIS)

2016-01-01

Radiation doses below 100 mSv are called low doses. Epidemiological research on the health hazards of low doses are difficult to do because numerous pathologies, particularly cancer, appear lifelong for genetical or environmental causes without any link with irradiation and it is very difficult to identify the real cause of a cancer. Another concern is that the impact on human health is weak and are observed only after a long period after irradiation. These features make epidemiological studies cumbersome to implement since they require vast cohorts and a very long-term follow-up. The extrapolation of the effects of higher doses to the domain of low doses does not meet reality and it is why the European Union takes part into the financing of such research. In order to gain efficiency, scientists work together through various European networks among them: HLEG (High Level Expert Group On European Low Dose Risk Research) or MELODI (Multidisciplinary European Low Dose Initiative). Several programs are underway or have been recently launched: -) the impact of Cesium contamination on children's health (Epice program), -) the study of the impact of medical imaging on children, -) the study of the health of children living near nuclear facilities, -) the relationship between radon and lung cancer, -) the effect of occupational low radiation doses, -) the effect of uranium dissolved in water on living organisms (Envirhom program). (A.C.)

Efficacy of Low-dose (2 millicurie) versus Standard-dose (4 millicurie) Radioiodine Treatment for Cats with Mild-to-Moderate Hyperthyroidism.

Science.gov (United States)

Lucy, J M; Peterson, M E; Randolph, J F; Scrivani, P V; Rishniw, M; Davignon, D L; Thompson, M S; Scarlett, J M

2017-03-01

Radioiodine ( 131 I) is effective treatment for hyperthyroidism in cats, but optimal dose to restore euthyroidism without inducing hypothyroidism is unclear. Treatment-induced hypothyroidism can lead to azotemia and reduced duration of survival. To compare efficacy and short-term outcomes of low-dose 131 I versus higher, standard-dose 131 I as treatment for hyperthyroidism. A total of 189 client-owned cats undergoing 131 I treatment for mild-to-moderate hyperthyroidism (serum T 4 ≥ 4.0 μg/dL and hyperthyroidism, overt hypothyroidism (low T 4 , high TSH), subclinical hypothyroidism (normal T 4 , high TSH), and azotemia. There was no significant difference in prevalence of cats with persistent hyperthyroidism between standard- and low-dose treatment groups at 3 (0% versus 5.3%; P = .34) and 6 (0% versus 3.3%; P = .51) months. Overt (18% versus 1%; P = .0005) or subclinical (46% versus 21%; P = .004) hypothyroidism was more common in cats at 6 months after standard-dose 131 I. No difference in incidence of azotemia existed between groups, but cats treated with standard-dose 131 I had higher creatinine concentrations (P effective for cats with mild-to-moderate hyperthyroidism, as evidenced by a cure rate of >95% with reduced frequency of iatrogenic hypothyroidism and azotemia. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Pharmacokinetics and tolerability of a higher rifampin dose versus the standard dose in pulmonary tuberculosis patients.

NARCIS (Netherlands)

Ruslami, R.; Nijland, H.M.J.; Alisjahbana, B.; Parwati, I.; Crevel, R. van; Aarnoutse, R.E.

2007-01-01

Rifampin is a key drug for tuberculosis (TB) treatment. The available data suggest that the currently applied 10-mg/kg of body weight dose of rifampin may be too low and that increasing the dose may shorten the treatment duration. A double-blind randomized phase II clinical trial was performed to

Benefit of high-dose daunorubicin in AML induction extends across cytogenetic and molecular groups.

Science.gov (United States)

Luskin, Marlise R; Lee, Ju-Whei; Fernandez, Hugo F; Abdel-Wahab, Omar; Bennett, John M; Ketterling, Rhett P; Lazarus, Hillard M; Levine, Ross L; Litzow, Mark R; Paietta, Elisabeth M; Patel, Jay P; Racevskis, Janis; Rowe, Jacob M; Tallman, Martin S; Sun, Zhuoxin; Luger, Selina M

2016-03-24

The initial report of the Eastern Cooperative Oncology Group-American College of Radiology Imaging Network Cancer Research Group trial E1900 (#NCT00049517) showed that induction therapy with high-dose (HD) daunorubicin (90 mg/m(2)) improved overall survival in adults cytogenetics or aFLT3-ITD mutation. Here, we update the results of E1900 after longer follow-up (median, 80.1 months among survivors), focusing on the benefit of HD daunorubicin on common genetic subgroups. Compared with standard-dose daunorubicin (45 mg/m(2)), HD daunorubicin is associated with a hazard ratio (HR) for death of 0.74 (P= .001). Younger patients (cytogenetics (HR, 0.51;P= .03 and HR, 0.68;P= .01, respectively). Patients with unfavorable cytogenetics were shown to benefit from HD daunorubicin on multivariable analysis (adjusted HR, 0.66;P= .04). Patients with FLT3-ITD (24%),DNMT3A(24%), and NPM1(26%) mutant AML all benefited from HD daunorubicin (HR, 0.61,P= .009; HR, 0.62,P= .02; and HR, 0.50,P= .002; respectively). HD benefit was seen in the subgroup of older patients (50-60 years) with the FLT3-ITD or NPM1 mutation. Additionally, the presence of an NPM1 mutation confers a favorable prognosis only for patients receiving anthracycline dose intensification during induction. © 2016 by The American Society of Hematology.

Assessment of mean glandular dose to patients from digital mammography systems

International Nuclear Information System (INIS)

Pwamang, Caroline K.

2016-07-01

Mean glandular dose assessment of patients undergoing digital mammography examination has been done. A total of 297 patient data was used for the study. Basic Quality Control tests were done to ascertain the performance of the equipment used. The results of Quality Control tests indicated that the three Mammography units used for this study were functioning within the internationally acceptable performance criteria. Patients with a breast thickness of 30 mm within the two age groups of 40-49 yrs and 50-64 yrs received doses slightly higher than the acceptable dose levels. A patient in the category 40-49 yrs with breast thickness of 30 mm received 1.83 mGy as calculated Mean Glandular Dose, 2.10 mGy was the recorded dose and 1.58 mGy was recorded under the age group 50-64 yrs. These values have deviated by -22%, -40%, and -5.33% respectively from 1.5 mGy which is the recommended dose for a breast thickness of 30 mm. Also patients with breast thickness of 70 mm under the age group 40–49 yrs had a recorded dose of 6.58 mGy, which deviated by -1.21% from the recommended value of 6.5 mGy for that breast thickness. Aside these values, all the other values were within the recommended dose values. The percentage deviation between the recommended values and the calculated values was within ±25% which was a working limit that was set for this work. Doses delivered by the Full-field Digital mammography equipment were higher than doses delivered by the Computered Radiography equipment. The calculated Mean Glandular Doses for the three facilities were within recommended dose values. (author)

Problems arising in the evaluation of collective dose commitment

International Nuclear Information System (INIS)

Coulon, R.; Beau, P.

1979-01-01

In order to apply the concept of optimization it is necessary to evaluate the collective dose commitment for the population as a whole. This is found by summing the dose commitments for the different population groups involved, including persons occupationally exposed and members of the public both locally and globally. The average dose received by each of these groups can vary considerably: for occupational exposure it is about one order of magnitude below the limits, whereas for the general public it is far below, although certain local groups may be subjected to a much higher exposure than the overall average. The question arises, therefore, whether certain groups should not be weighted differently in order to take into account the heterogeneity of the distribution of exposure. As far as the validity of forecast evaluations is concerned, one may assume that for occupational exposure the dose commitment over the whole period of operation of a facility can be estimated fairly accurately. The overall collective dose commitment for the public is relatively insensitive to local variations in the environment and in the public itself but is strongly dependent on long-term developments which cannot at present be forecast. For the evaluation of dose equivalent to the critical group, local variations are of considerable importance and need to be foreseen, which is not always possible. By taking into account a period which includes the annual maximum collective dose equivalent one can make some of these difficulties less severe. (author)

Conflict Management in Student Groups - a Teacher’s Perspective in Higher Education

OpenAIRE

Markus Borg; Joakim Kembro; Jesper Notander; Catarina Petersson; Lars Ohlsson

2011-01-01

Students working in groups is a commonly used method of instruction in higher education, popularized by the introduction of problem based learning. As a result, management of small groups of people has become an important skill for teachers. The objective of our study is to investigate why conflicts arise in student groups at the Faculty of Engineering at Lund University and how teachers manage them. We have conducted an exploratory interdepartmental interview study on teachers' views on this...

Exploring Radiotherapy Targeting Strategy and Dose: A Pooled Analysis of Cooperative Group Trials of Combined Modality Therapy for Stage III Non-Small Cell Lung Cancer.

Science.gov (United States)

Schild, Steven E; Fan, Wen; Stinchcombe, Thomas E; Vokes, Everett E; Ramalingam, Suresh S; Bradley, Jeffrey D; Kelly, Karen; Pang, Herbert H; Wang, Xiaofei

2018-04-21

Concurrent chemoradiotherapy(CRT) is standard therapy for locally-advanced non-small-cell lung cancer(LA-NSCLC)patients. This study was performed to examine thoracic radiotherapy(TRT) parameters and their impact on patient survival. We collected Individual patient data(IPD) from 3600LA-NSCLC patients participating in 16 cooperative group trials of concurrent CRT. The primary TRT parameters examined included field design strategy(elective nodal irradiation(ENI) compared to involved field TRT(IF-TRT)), total dose, and biologically effective dose(BED). Hazard ratios(HRs) for overall survival were calculated with univariable and multivariable Cox models. TRT doses ranged from 60 to 74 Gy with most treatments administered once-daily. ENI was associated with poorer survival than IF-TRT(univariable HR,1.37;95%CI,1.24-1.51,pENI patients were 24 and 16 months, respectively. Patients were divided into 3 dose groups: low total dose(60 Gy), medium total dose(>60Gy-66Gy) and high total dose(>66Gy-74 Gy). With reference to the low dose group, the multivariable HR's were 1.08 for the medium dose group(95%CI=0.93-1.25) and 1.12 for the high dose group(CI=0.97-1.30).The univariate p=0.054 and multivariable p=0.17. BED was grouped as follows: low(55.5 Gy 10 ). With reference to the low BED group, the HR was 1.00(95%CI=0.85-1.18) for the medium BED group and 1.10(95%CI=0.93-1.31) for the high BED group. The univariable p=0.076 and multivariable p=0.16. For LA-NSCLC patients treated with concurrent CRT, IF-TRT was associated with significantly better survival than ENI-TRT. TRT total and BED dose levels were not significantly associated with patient survival. Future progress will require research focusing on better systemic therapy and TRT. Copyright © 2018. Published by Elsevier Inc.

Assessment of individual dose utilization vs. physician prescribing recommendations for recombinant activated factor VII (rFVIIa) in paediatric and adult patients with congenital haemophilia and alloantibody inhibitors (CHwI): the Dosing Observational Study in Hemophilia (DOSE).

Science.gov (United States)

Gruppo, R A; Kessler, C M; Neufeld, E J; Cooper, D L

2013-07-01

Recent data from the Dosing Observational Study in Hemophilia diary study has described home treatment with recombinant activated factor VII (rFVIIa) in congenital haemophilia with inhibitors (CHwI). The current analysis compares prescribed and patient/caregiver-reported rFVIIa administration in paediatric and adult CHwI patients in this study. Patients with ≥ 4 bleeding episodes within a 3-month period prescribed rFVIIa as first-line therapy for bleeding episodes were eligible. Patients/caregivers completed a diary for ≥ 90 days or until the patient experienced four bleeds. Initial, total and mean rFVIIa doses reported for each bleeding episode were calculated and compared with the physician-prescribed doses. Of 52 enrolled patients (25 children; 27 adults), 39 (75%) completed the study. Children and adults had similar mean durations of bleeding episodes. Both patient groups were administered higher initial rFVIIa doses for joint bleeds than prescribed: median (range) 215.2 (74.1-400.0) mcg kg(-1) vs. 200.0 (61.0-270.0) mcg kg(-1) for children, and 231.3 (59.3-379.7) mcg kg(-1) vs. 123.0 (81.0-289.0) mcg kg(-1) for adults. The median infused dose for joint bleeds was higher in adults than children (175.2 vs. 148.0 mcg kg(-1) ), but children received significantly more doses per joint bleed than adults (median 6.5 vs. 3.0). The median total dose per joint bleed was higher in children than adults (1248.7 vs. 441.6). For children and adults, both initial and additional doses administered for bleeds were higher than prescribed. Children received higher total doses per bleed due to an increased number of infusions per bleed. © 2013 John Wiley & Sons Ltd.

Dose-ranging pharmacokinetics of colistin methanesulphonate (CMS) and colistin in rats following single intravenous CMS doses.

Science.gov (United States)

Marchand, Sandrine; Lamarche, Isabelle; Gobin, Patrice; Couet, William

2010-08-01

The aim of this study was to evaluate the effect of colistin methanesulphonate (CMS) dose on CMS and colistin pharmacokinetics in rats. Three rats per group received an intravenous bolus of CMS at a dose of 5, 15, 30, 60 or 120 mg/kg. Arterial blood samples were drawn at 0, 5, 15, 30, 60, 90, 120, 150 and 180 min. CMS and colistin plasma concentrations were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The pharmacokinetic parameters of CMS and colistin were calculated by non-compartmental analysis. Linear relationships were observed between CMS and colistin AUCs to infinity and CMS doses, as well as between CMS and colistin C(max) and CMS doses. CMS and colistin pharmacokinetics were linear for a range of colistin concentrations covering the range of values encountered and recommended in patients even during treatment with higher doses.

A comparison of submicrometer particle dose between Australian and Italian people

International Nuclear Information System (INIS)

Buonanno, G.; Morawska, L.; Stabile, L.; Wang, L.; Giovinco, G.

2012-01-01

Alveolar and tracheobronchial-deposited submicrometer particle number and surface area data received by different age groups in Australia are shown. Activity patterns were combined with microenvironmental data through a Monte Carlo method. Particle number distributions for the most significant microenvironments were obtained from our measurement survey data and people activity pattern data from the Australian Human Activity Pattern Survey were used. Daily alveolar particle number (surface area) dose received by all age groups was equal to 3.0 × 10 10 particles (4.5 × 10 2 mm 2 ), varying slightly between males and females. In contrast to gender, the lifestyle was found to significantly affect the daily dose, with highest depositions characterizing adults. The main contribution was due to indoor microenvironments. Finally a comparison between Italian and Australian people in terms of received particle dose was reported; it shows that different cooking styles can affect dose levels: higher doses were received by Italians, mainly due to their particular cooking activity. - Highlights: ► Particle number and surface area deposition in alveolar and tracheobronchial areas. ► Activity pattern and microenvironment data combination by Monte Carlo simulation. ► Deposition increases as a function of age group: maximum value for 19–40 years old. ► Major contributions arise from cooking, eating and transportation activities. ► Italian people statistically experience a dose higher than Australian one. - Alveolar and tracheobronchial-deposited submicrometer particle doses, in terms of number and surface area, were evaluated through a Monte Carlo method for different age groups population in Brisbane, Australia and compared to previously published Italian data.

Clinical study of double dose of valsartan combined with tacrolimus in treatment of diabetic nephropathy.

Science.gov (United States)

Jin, H; Zhang, H-N; Hou, X-L; Zhang, B; Wu, J; Zhang, H-B

2016-01-01

To investigate the clinical effect of double dose of valsartan combined with tacrolimus in the treatment of diabetic nephropathy (DN). HA total of 86 cases diagnosed with DN were selected from October 2013 to October 2014 in Zaozhuang Municipal Hospital, China. The study was approved by our hospital Ethics Committee and written consent was obtained from patients and their family members. Patients were randomly divided into three groups according to the sequence of admission, group A (conventional dose of valsartan group, n = 28 cases), group B (double dose of valsartan group, n = 29 cases) and group C (double dose of valsartan combined with tacrolimus group, n = 29). Clinical effects were compared by analyzing the renal function tests after 8 weeks. 24h urine protein, serum creatinine level of patients in group B and group C were significantly lower than that of group A. Those in group C was much lower. The glomerular filtration rates were significantly higher for group B and C than that of group A, and those in group C were much higher. The difference is statistically significant (p valsartan combined with tacrolimus treatment of DN patients can improve clinical symptoms, reducing inflammation, inhibiting or even reversing the interstitial fibrosis, which will improve the curative effect and reduce the recurrence, as to provide a new theoretical basis for the clinical treatment of the disease.

Age-specific radiation dose commitment factors for a one-year chronic intake

International Nuclear Information System (INIS)

Hoenes, G.R.; Soldat, J.K.

1977-11-01

During the licensing process for nuclear facilities, radiation doses and dose commitments must be calculated for people in the environs of a nuclear facility. These radiation doses are determined by examining characteristics of population groups, pathways to people, and radionuclides found in those pathways. The pertinent characteristics, which are important in the sense of contributing a significant portion of the total dose, must then be analyzed in depth. Dose factors are generally available for adults, see Reference 1 for example, however numerous improvements in data on decay schemes and half-lives have been made in recent years. In addition, it is advisable to define parameters for calculation of the radiation dose for ages other than adults since the population surrounding nuclear facilities will be composed of various age groups. Further, since infants, children, and teens may have higher rates of intake per unit body mass, it is conceivable that the maximally exposed individual may not be an adult. Thus, it was necessary to develop new radiation-dose commitment factors for various age groups. Dose commitment factors presented in this report have been calculated for a 50-year time period for four age groups

Quality control of sickness rate registration of the Chernobil accident liquidators into a different radiation dose groups

International Nuclear Information System (INIS)

Biryukov, A.P.; Ivanov, V.K.; Bolokhonenkova, M.A.; Kochergina, E.V.; Kruglova, Z.G.; Zelenskaya, N.S.; Ukraintsev, V.F.

2005-01-01

Effect of the dose factor on the quality of registration of the liquidator health state is studied. It is shown that the efficiency of prophylactic system and monitoring intensity in the different dose groups are equal, are determined by general legislative acts on the all territory of the Russian Federation and do not influence the results of carrying out the radiation-epidemic analysis [ru

Poster - 56: Preliminary comparison of FF- and FFF-VMAT for prostate plans with higher rectal dose

International Nuclear Information System (INIS)

Liu, Baochang; Darko, Johnson; Osei, Ernest

2016-01-01

Purpose: A recent retrospective study found 53 patients previously treated to 78Gy/39 using flattened filtered (FF) 6X-VMAT at GRRCC had rectal DVH more than one standard deviation higher than the average. This study was to investigate if using 6FFFor10FFF beams could reduce these DVHs without compromising target coverage. Methods: Twenty patients’ plans were re-planed with 2-arc 6X-VMAT, 6FFF-VMAT and 10FFF-VMAT using the Eclipse TPS following departmental protocol. All plans had the same optimization and normalization, and were evaluated against the acceptance criteria from the QUANTEC and Emami. Statistical differences in the mean dose to OARs (D m ) and PTV homogeneity index (HI) between energies were tested using the paired sample Wilcoxon signed rank statistical method (p<0.05). Beam delivery accuracy was checked on five patients using portal dosimetry (PD). Results: The PTV HI for the 10FFF shows no statistical difference from the 6X. All the OARs, except left femoral head with 6FFF, have significantly lower Dm using 6FFF and 10FFF .There is no difference in the maximum doses to rectum and bladder and are limited by the prescribed doses. Measurements show good agreements in the gamma evaluation (3%/3mm) for all energies. Conclusion: This preliminary study shows that doses to the OARs are reduced using 10FFF for the same target coverage. The plans using 6FFF result in lower doses to some OARs, and statistically different PTV HI. All plans showed very good agreement with measurements.

Poster - 56: Preliminary comparison of FF- and FFF-VMAT for prostate plans with higher rectal dose

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Liu, Baochang; Darko, Johnson; Osei, Ernest [Grand River Regional Cancer Centre, Kitchener, Ontario (Canada)

2016-08-15

Purpose: A recent retrospective study found 53 patients previously treated to 78Gy/39 using flattened filtered (FF) 6X-VMAT at GRRCC had rectal DVH more than one standard deviation higher than the average. This study was to investigate if using 6FFFor10FFF beams could reduce these DVHs without compromising target coverage. Methods: Twenty patients’ plans were re-planed with 2-arc 6X-VMAT, 6FFF-VMAT and 10FFF-VMAT using the Eclipse TPS following departmental protocol. All plans had the same optimization and normalization, and were evaluated against the acceptance criteria from the QUANTEC and Emami. Statistical differences in the mean dose to OARs (D{sub m}) and PTV homogeneity index (HI) between energies were tested using the paired sample Wilcoxon signed rank statistical method (p<0.05). Beam delivery accuracy was checked on five patients using portal dosimetry (PD). Results: The PTV HI for the 10FFF shows no statistical difference from the 6X. All the OARs, except left femoral head with 6FFF, have significantly lower Dm using 6FFF and 10FFF .There is no difference in the maximum doses to rectum and bladder and are limited by the prescribed doses. Measurements show good agreements in the gamma evaluation (3%/3mm) for all energies. Conclusion: This preliminary study shows that doses to the OARs are reduced using 10FFF for the same target coverage. The plans using 6FFF result in lower doses to some OARs, and statistically different PTV HI. All plans showed very good agreement with measurements.

Metformin and weight loss in obese women with polycystic ovary syndrome: comparison of doses.

Science.gov (United States)

Harborne, Lyndal R; Sattar, Naveed; Norman, Jane E; Fleming, Richard

2005-08-01

Metformin treatment of women with polycystic ovary syndrome (PCOS) is widespread, as determined by studies with diverse patient populations. No comparative examination of weight changes or metabolite responses to different doses has been reported. The aim of this study was to determine whether different doses of metformin (1500 or 2550 mg/d) would have different effects on body weight, circulating hormones, markers of inflammation, and lipid profiles. The study included prospective cohorts randomized to two doses of metformin. The study was performed at a university teaching hospital with patients from gynecology/endocrinology clinics. The patients studied were obese (body mass index, 30 to or =37 kg/m2; n = 41) women with PCOS. Patients were randomized to two doses of metformin, and parameters were assessed after 4 and 8 months. The main outcome measures were changes in body mass, circulating hormones, markers of inflammation, and lipid profiles. Intention to treat analyses showed significant weight loss in both dose groups. Only the obese subgroup showed a dose relationship (1.5 and 3.6 kg in 1500- and 2550-mg groups, respectively; P = 0.04). The morbidly obese group showed similar reductions (3.9 and 3.8 kg) in both groups. Suppression of androstenedione was significant with both metformin doses, but there was no clear dose relationship. Generally, beneficial changes in lipid profiles were not related to dose. Weight loss is a feature of protracted metformin therapy in obese women with PCOS, with greater weight reduction potentially achievable with higher doses. Additional studies are required to determine whether other aspects of the disorder may benefit from the higher dose of metformin.

Impact of cyclophosphamide dose of conditioning on the outcome of allogeneic hematopoietic stem cell transplantation for aplastic anemia from human leukocyte antigen-identical sibling.

Science.gov (United States)

Mori, Takehiko; Koh, Hideo; Onishi, Yasushi; Kako, Shinichi; Onizuka, Makoto; Kanamori, Heiwa; Ozawa, Yukiyasu; Kato, Chiaki; Iida, Hiroatsu; Suzuki, Ritsuro; Ichinohe, Tatsuo; Kanda, Yoshinobu; Maeda, Tetsuo; Nakao, Shinji; Yamazaki, Hirohito

2016-04-01

The standard conditioning regimen in allogeneic hematopoietic stem cell transplantation (HSCT) for aplastic anemia from a human leukocyte antigen (HLA)-identical sibling has been high-dose cyclophosphamide (CY 200 mg/kg). In the present study, results for 203 patients with aplastic anemia aged 16 years or older who underwent allogeneic HSCT from HLA-identical siblings were retrospectively analyzed using the registry database of Japan Society for Hematopoietic Cell Transplantation. Conditioning regimens were defined as a (1) high-dose CY (200 mg/kg or greater)-based (n = 117); (2) reduced-dose CY (100 mg/kg or greater, but less than 200 mg/kg)-based (n = 38); and (3) low-dose CY (less than 100 mg/kg)-based (n = 48) regimen. Patient age and the proportion of patients receiving fludarabine were significantly higher in the reduced- and low-dose CY groups than the high-dose CY group. Engraftment was comparable among the groups. Five-year overall survival (OS) tended to be higher in the low-dose CY group [93.0 % (95 % CI 85.1-100.0 %)] than the high-dose CY [84.2 % (95 % CI 77.1-91.3 %)] or reduced-dose CY groups [83.8 % (95 % CI 71.8-95.8 %); P = 0.214]. Age-adjusted OS was higher in the low-dose CY group than the high- and reduced-dose CY groups with borderline significance (P = 0.067). These results suggest that CY dose can safely be reduced without increasing graft rejection by adding fludarabine in allogeneic HSCT for aplastic anemia from an HLA-identical sibling.

Patient dose audit of the most frequent radiographic examinations and the proposed local diagnostic reference levels in southwestern Nigeria: Imperative for dose optimisation

Directory of Open Access Journals (Sweden)

N.N. Jibiri

2016-07-01

Full Text Available Diagnostic reference levels (DRLs is a veritable tool for dose optimisation and patient protection in diagnostic radiology. However, it is essential to have information on the local situation especially in a large hospital with several units or a cluster of healthcare centres within a geographical region with several X-ray units. In the present study, entrance surface doses (ESDs were measured in twelve (12 healthcare centres consisting of 15 radiological units using thermoluminescent dosimeters (TLDs. Seven radiological procedures such as; chest PA, abdomen AP, pelvis AP, lumbar spine AP, skull AP, knee AP, and hand AP frequently carried out in Nigeria were included in the study, and their local diagnostic reference levels (LDRLs were determined. The values of the determined LDRLs were compared with established NDRLs in UK, US, Slovenia, Italy and Brazil. The LDRLs determined in the two groups (healthcare centres studied ranged from 1.78 to 3.01, 2.71 to 2.84, 2.11 to 3.79, 3.93 to 8.79, 1.06 to 1.73 and 1.10 to 1.44 mGy for chest PA, pelvis AP, lumbar spine AP, skull AP, knee AP and hand AP respectively. Large variations were found among the X-ray units studied even within the same centre. Entrance surface doses obtained in pelvis AP and lumbar spine AP in both GROUP A and were found to be lower than the NRPB-HPA 2010 review for UK, while in all other five examinations, value of the measured entrance surface dose (ESD are higher than the doses reported in the UK review. The relative higher doses found in the study are attributable to higher tube load (mAs used and indicative of the need for dose optimisation in Nigerian radiological practice.

Dose Specification and Quality Assurance of Radiation Therapy Oncology Group Protocol 95-17; a Cooperative Group Study of Iridium-192 Breast Implants as Sole Therapy

International Nuclear Information System (INIS)

Ibbott, Geoffrey S.; Hanson, W.F.; O'Meara, Elizabeth; Kuske, Robert R.; Arthur, Douglas; Rabinovitch, Rachel; White, Julia; Wilenzick, Raymond M.; Harris, Irene; Tailor, Ramesh C.

2007-01-01

Purpose: The Radiation Therapy Oncology Group (RTOG) protocol 95-17 was a Phase I/II trial to evaluate multicatheter brachytherapy as the sole method of adjuvant breast radiotherapy for Stage I/II breast carcinoma after breast-conserving surgery. Low- or high-dose-rate sources were allowed. Dose prescription and treatment evaluation were based on recommendations in the International Commission on Radiation Units and Measurements (ICRU), Report 58 and included the parameters mean central dose (MCD), average peripheral dose, dose homogeneity index (DHI), and the dimensions of the low- and high-dose regions. Methods and Materials: Three levels of quality assurance were implemented: (1) credentialing of institutions was required before entering patients into the study; (2) rapid review of each treatment plan was conducted before treatment; and (3) retrospective review was performed by the Radiological Physics Center in conjunction with the study chairman and RTOG dosimetry staff. Results: Credentialing focused on the accuracy of dose calculation algorithm and compliance with protocol guidelines. Rapid review was designed to identify and correct deviations from the protocol before treatment. The retrospective review involved recalculation of dosimetry parameters and review of dose distributions to evaluate the treatment. Specifying both central and peripheral doses resulted in uniform dose distributions, with a mean dose homogeneity index of 0.83 ± 0.06. Conclusions: Vigorous quality assurance resulted in a high-quality study with few deviations; only 4 of 100 patients were judged as representing minor variations from protocol, and no patient was judged as representing major deviation. This study should be considered a model for quality assurance of future trials

Superiority of split dose midazolam as conscious sedation for outpatient colonoscopy.

Science.gov (United States)

Lee, Hyuk; Kim, Jeong Hwan

2009-08-14

To elucidate the efficacy and safety of a split dose of midazolam in combination with meperidine for colonoscopy. Eighty subjects undergoing outpatient colonoscopy were randomly assigned to group A or B. Group A (n = 40) received a split dose of midazolam in combination with meperidine. Group B (n = 40) received a single dose of midazolam in combination with meperidine. Outcome measurements were level of sedation, duration of sedation and recovery, degree of pain and satisfaction, procedure-related memory, controllability, and adverse events. Group A had a lower frequency of significant hypoxemia (P = 0.043) and a higher sedation score on withdrawal of the endoscope from the descending colon than group B (P = 0.043). Group B recovered from sedation slightly sooner than group A (P memory, except insertion-related memory, were lower in group A one week after colonoscopic examination (P = 0.018 and P sedation status during colonoscopic examination and a reduction in procedure-related pain and memory, but resulted in longer recovery time.

Dose reduction in spiral CT angiography of thoracic outlet syndrome by anatomically adapted tube current modulation

International Nuclear Information System (INIS)

Mastora, I.; Remy-Jardin, M.; Remy, J.; Suess, C.; Scherf, C.; Guillot, J.P.

2001-01-01

The aim of this study was to evaluate dose reduction in spiral CT angiography of the thoracic outlet by on-line tube-current control. Prospectively, 114 patients undergoing spiral CT angiography of the subclavian artery for thoracic outlet arterial syndromes were evaluated with and without tube-current modulation at the same session (scanning parameters for the two successive angiograms, one in the neutral position and one after the postural maneuver): 140 kV; 206 mA; scan time 0.75 s; collimation 3 mm; pitch = (1). The dose reduction system was applied in the neutral position in the first 92 consecutive patients and after postural maneuver in the remaining 22 consecutive patients. Dose reduction and image quality were analyzed in the overall study group (group 1; n = 114). The influence of the arm position was assessed in 44 of the 114 patients (group 2), matched by the transverse diameter of the upper thorax. The mean dose reduction was 33 % in group 1 (range 22-40 %) and 34 % in group 2 (range 26-40 %). In group 2 the only difference in image quality was a significantly higher frequency of graininess on low-dose scans compared with reference scans whatever the patient's arm position, graded as minimal in 38 of the 44 patients (86 %). When the low-dose technique was applied after postural maneuver in group 2: (a) the mean dose reduction was significantly higher (35 vs 32 % in the neutral position; p = 0.006); (b) graininess was less frequent (82 vs 91 % in the neutral position); and (c) the percentage of graininess graded as minimal was significantly higher (83 vs 70 % in the neutral position; p = 0.2027). On-line tube-current modulation enables dose reduction on high-quality, diagnostic spiral CT angiograms of the thoracic outlet and should be applied during data acquisition in the neutral position and after postural maneuver for optimal use. (orig.)

Dose reduction in spiral CT angiography of thoracic outlet syndrome by anatomically adapted tube current modulation

Energy Technology Data Exchange (ETDEWEB)

Mastora, I.; Remy-Jardin, M.; Remy, J. [Dept. of Radiology, University Center Hospital Calmette, Lille (France); Medical Research Group, Lille (France); Suess, C.; Scherf, C. [Siemens Medical Systems, Forcheim (Germany); Guillot, J.P. [Dept. of Radiology, University Center Hospital Calmette, Lille (France)

2001-04-01

The aim of this study was to evaluate dose reduction in spiral CT angiography of the thoracic outlet by on-line tube-current control. Prospectively, 114 patients undergoing spiral CT angiography of the subclavian artery for thoracic outlet arterial syndromes were evaluated with and without tube-current modulation at the same session (scanning parameters for the two successive angiograms, one in the neutral position and one after the postural maneuver): 140 kV; 206 mA; scan time 0.75 s; collimation 3 mm; pitch = (1). The dose reduction system was applied in the neutral position in the first 92 consecutive patients and after postural maneuver in the remaining 22 consecutive patients. Dose reduction and image quality were analyzed in the overall study group (group 1; n = 114). The influence of the arm position was assessed in 44 of the 114 patients (group 2), matched by the transverse diameter of the upper thorax. The mean dose reduction was 33 % in group 1 (range 22-40 %) and 34 % in group 2 (range 26-40 %). In group 2 the only difference in image quality was a significantly higher frequency of graininess on low-dose scans compared with reference scans whatever the patient's arm position, graded as minimal in 38 of the 44 patients (86 %). When the low-dose technique was applied after postural maneuver in group 2: (a) the mean dose reduction was significantly higher (35 vs 32 % in the neutral position; p = 0.006); (b) graininess was less frequent (82 vs 91 % in the neutral position); and (c) the percentage of graininess graded as minimal was significantly higher (83 vs 70 % in the neutral position; p = 0.2027). On-line tube-current modulation enables dose reduction on high-quality, diagnostic spiral CT angiograms of the thoracic outlet and should be applied during data acquisition in the neutral position and after postural maneuver for optimal use. (orig.)

[Clinical applications of dosing algorithm in the predication of warfarin maintenance dose].

Science.gov (United States)

Huang, Sheng-wen; Xiang, Dao-kang; An, Bang-quan; Li, Gui-fang; Huang, Ling; Wu, Hai-li

2011-12-27

To evaluate the feasibility of clinical application for genetic based dosing algorithm in the predication of warfarin maintenance dose in Chinese population. The clinical data were collected and blood samples harvested from a total of 126 patients undergoing heart valve replacement. The genotypes of VKORC1 and CYP2C9 were determined by melting curve analysis after PCR. They were divided randomly into the study and control groups. In the study group, the first three doses of warfarin were prescribed according to the predicted warfarin maintenance dose while warfarin was initiated at 2.5 mg/d in the control group. The warfarin doses were adjusted according to the measured international normalized ratio (INR) values. And all subjects were followed for 50 days after an initiation of warfarin therapy. At the end of a 50-day follow-up period, the proportions of the patients on a stable dose were 82.4% (42/51) and 62.5% (30/48) for the study and control groups respectively. The mean durations of reaching a stable dose of warfarin were (27.5 ± 1.8) and (34.7 ± 1.8) days and the median durations were (24.0 ± 1.7) and (33.0 ± 4.5) days in the study and control groups respectively. Significant differences existed in the durations of reaching a stable dose between the two groups (P = 0.012). Compared with the control group, the hazard ratio (HR) for the duration of reaching a stable dose was 1.786 in the study group (95%CI 1.088 - 2.875, P = 0.026). The predicted dosing algorithm incorporating genetic and non-genetic factors may shorten the duration of achieving efficiently a stable dose of warfarin. And the present study validates the feasibility of its clinical application.

Utilization of the higher plants in a study on hereditary effect of low-dose irradiation

International Nuclear Information System (INIS)

Yamashita, Jun

1976-01-01

Some problems in a study of hereditary effect of low-dose irradiation, which used the higher plants (tradescantia, peas, etc.) as materials, were mentioned. Conditions to be used as materials were mentioned as follows: 1) the materials must have high radio-sensitivity, 2) the natural mutation of the materials must be low, 3) hereditary uniformity and stability of genes in the materials were important, and 4) in case of considering the materials as environmental radiation monitors, the observation period must be long and the duration from exposure to detection of mutation must be short. Tradescantia has most of these conditions, but the greatest fault is that the object of its observation is mutation of somatic cells, and hereditary study is impossible. Therefore, it is necessary to find out other materials in order to solve the problem whether there is a difference in relative frequency of chromosomal abnormalities, which occurrs in germinal cells and is transmitted to posterity, between low and high doses or not. (Serizawa, K.)

Group Decision Making in Higher Education Using the Analytic Hierarchy Process.

Science.gov (United States)

Liberatore, Matthew J.; Nydick, Robert L.

1997-01-01

Examines application of the analytic hierarchy process (AHP) to group decision-making and evaluation situations in higher education. The approach is illustrated by (1) evaluation of academic research papers at Villanova University (Pennsylvania), and (2) a suggested adaptation for the more complex problem of institutionwide strategic planning.…

Cost reduction in abdominal CT by weight-adjusted dose.

Science.gov (United States)

Arana, Estanislao; Martí-Bonmatí, Luis; Tobarra, Eva; Sierra, Consuelo

2009-06-01

To analyze the influence of contrast dose adjusted by weight vs. fixed contrast dose in the attenuation and cost of abdominal computed tomography (CT). A randomised, consecutive, parallel group study was conducted in 151 patients (74 men and 77 women, age range 22-67 years), studied with the same CT helical protocol. A dose at 1.75 ml/kg was administered in 101 patients while 50 patients had a fixed dose of 120 ml of same non-ionic contrast material (320 mg/ml). Mean enhancements were measured at right hepatic lobe, superior abdominal aorta and inferior cava vein. Statistical analysis was weight-stratified (81 kg). Aortic attenuation was significantly superior (p61 kg in dose-adjusted group, presented higher hepatic attenuation, being statistically significant in those >81 kg (p80 kg, there was an over cost of euro 10.7 per patient. An injection volume of 1.75 ml/kg offers an optimal diagnostic quality with a global savings of euro 1.34 per patient.

Analyzed immunogenicity of fractional doses of Sabin-inactivated poliovirus vaccine (sIPV) with intradermal delivery in rats.

Science.gov (United States)

Ma, Lei; Cai, Wei; Sun, Mingbo; Cun, Yina; Zhou, Jian; Liu, Jing; Hu, Wenzhu; Zhang, Xinwen; Song, Shaohui; Jiang, Shude; Liao, Guoyang

2016-12-01

The live-attenuated oral polio vaccine (OPV) will be no longer used when wild poliovirus (WPV) eliminating in worldwide, according to GPEI (the Global Polio Eradication Initiative) Reports. It is planning to replace OPV by Sabin-based inactivated poliovirus vaccine (sIPV) in developing countries, with purpose of reducing of the economic burden and maintaining of the appropriate antibody levels in population. It studied serial fractional doses immunized by intradermal injection (ID) in rats, to reduce consume of antigen and financial burden, maintaining sufficient immunogenicity; Methods: Study groups were divided in 4 groups of dose gradient, which were one-tenth (1/10), one-fifth (1/5), one-third (1/3) and one-full dose (1/1), according to the volume of distribution taken from the same batch of vaccine (sIPV). Wistar rats were injected intradermally with the needle and syringe sing the mantoux technique taken once month for 3 times. It was used as positive control that intramuscular inoculation (IM) was injected with one-full dose (1/1) with same batch of sIPV. PBS was used as negative control. Blood samples were collected via tail vein. After 30 d with 3 round of immunization, it analyzed the changes of neutralization antibody titers in the each group by each immunization program end; Results: The results of seroconversion had positive correlation with different doses in ID groups. The higher concentration of D-antigen (D-Ag) could conduct higher seroconversion. Furthermore, different types of viruses had different seroconversion trend. It showed that the geometric mean titers (GMTs) of each fractional-dose ID groups increased by higher concentration of D-Ag, and it got significant lower than the full-dose IM group. At 90 th days of immunization, the GMTs for each poliovirus subtypes of fractional doses were almost higher than 1:8, implied that it could be meaning positive seroprotection titer for polio vaccine types, according to WHO suggestion; Conclusions

Effects of low dose gamma-ray radiation on the seed germination and physiological activity of vegetable crops

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Kim, J. S.; Baek, M. H.; Lee, Y. G. [KAERI, Taejon (Korea, Republic of); Jung, K. H. [Kyunghee Univ., Yongin (Korea, Republic of)

2000-10-01

To determine the effect of low dose gamma-ray radiation on the germination rate and physiology of germinative seeds of Chinese cabbage(Brassica campestris L. cv. Hanyoreum) and radish(Raphanus sativus L. cv. Chungsukoungzoung). The germination rate of irradiation group was higher than that of the control. Especially it was highest at the early stage of induction. The germination rate of Chinese cabbage increased at 4 Gy-, 10 Gy- and 50 Gy irradiation group and that of radish increased at 2 Gy-, 6 Gy- and 10 Gy irradiation group. The seedling height of Chinese cabbage and radish increased positively in low dose irradiation group. The seedling height of Chinese cabbage was noticeably higher at 4 Gy and 10 Gy irradiation group and that of radish at 6 Gy irradiation group. The protein contents of seeds irradiated with low dose gamma-ray radiation was increased compared to that of the control especially at the early stage of induction. The enzyme activity of seeds irradiated with low dose of gamma-ray radiation was increased at 4 Gy and 10 Gy irradiation group. These results suggest that the germination and physiological activity of old seeds could be stimulated promisingly by the low dose gamma-ray radiation.

Infusion dose requirement of rocuronium in patients on phenytoin therapy - A prospective comparative study.

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Sheshadri, Veena; Radhakrishnan, Arathi; Halemani, Kusuma; Keshavan, Venkatesh H

2017-10-01

Patients with intracranial tumour are usually on anticonvulsants. Patients on phenytoin therapy demonstrate rapid metabolism of nondepolarising muscle relaxants secondary to enzyme induction. Infusion dose requirement of rocuronium in such patients has been sparingly studied. We studied the continuous infusion dose requirement of rocuronium bromide in patients on phenytoin therapy and its correlation with serum levels of phenytoin. Seventy-five patients scheduled for supratentorial tumour surgery were included in the study. Patients not on phenytoin were taken as control. The primary outcome variable studied was the infusion dose requirement of rocuronium in patients on phenytoin. Based on pre-operative serum phenytoin levels, study group patients were divided into two groups: sub-therapeutic level group (phenytoin level 10 μg/mL). Following anaesthesia induction, rocuronium bromide 0.6 mg/kg was administered to achieve tracheal intubation. Rocuronium infusion was titrated to maintain zero response on the train-of-four response. Demographic data were comparable. Patients receiving phenytoin required higher infusion dose compared to the control group (0.429 ± 0.2 mg/kg/h vs. 0.265 ± 0.15 mg/kg/h, P rocuronium (0.429 ± 0.205 mg/kg/h vs. 0.429 ± 0.265 mg/kg/h ( P = 0.815). The recovery was faster in the phenytoin group compared to the control group. Haowever, it was not clinically significant. The infusion dose requirement of rocuronium bromide in patients on phenytoin is higher and the serum levels of phenytoin does not influence the dose required.

The choice of food consumption rates for radiation dose assessments

International Nuclear Information System (INIS)

Simmonds, J.R.; Webb, G.A.M.

1981-01-01

The practical problem in estimating radiation doses due to radioactive contamination of food is the choice of the appropriate food intakes. To ensure compliance or to compare with dose equivalent limits, higher than average intake rates appropriate to critical groups should be used. However for realistic estimates of health detriment in the whole exposed population, average intake rates are more appropriate. (U.K.)

Can low-dose CT with iterative reconstruction reduce both the radiation dose and the amount of iodine contrast medium in a dynamic CT study of the liver?

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Takahashi, Hiroto; Okada, Masahiro; Hyodo, Tomoko; Hidaka, Syojiro; Kagawa, Yuki; Matsuki, Mitsuru; Tsurusaki, Masakatsu; Murakami, Takamichi, E-mail: murakami@med.kindai.ac.jp

2014-04-15

Purpose: To investigate whether low-dose dynamic CT of the liver with iterative reconstruction can reduce both the radiation dose and the amount of contrast medium. Materials and methods: This study was approved by our institutional review board. 113 patients were randomly assigned to one of two groups. Group A/group B (fifty-eight/fifty-five patients) underwent liver dynamic CT at 120/100 kV, with 0/40% adaptive statistical iterative reconstruction (ASIR), with a contrast dose of 600/480 mg I/kg, respectively. Radiation exposure was estimated based on the manufacturer's phantom data. The enhancement value of the hepatic parenchyma, vessels and the tumor-to-liver contrast of hepatocellular carcinomas (HCCs) were compared between two groups. Two readers independently assessed the CT images of the hepatic parenchyma and HCCs. Results: The mean CT dose indices: 6.38/4.04 mGy, the dose-length products: 194.54/124.57 mGy cm, for group A/group B. The mean enhancement value of the hepatic parenchyma and the tumor-to-liver contrast of HCCs with diameters greater than 1 cm in the post-contrast all phases did not differ significantly between two groups (P > 0.05). The enhancement values of vessels in group B were significantly higher than that in group A in the delayed phases (P < 0.05). Two reader's confidence levels for the hepatic parenchyma in the delayed phases and HCCs did not differ significantly between the groups (P > 0.05). Conclusions: Low-dose dynamic CT with ASIR can reduce both the radiation dose and the amount of contrast medium without image quality degradation, compared to conventional dynamic CT without ASIR.

Relationship between radiation dose and changes of blood cells in medical diagnostic X-ray workers in China

International Nuclear Information System (INIS)

Zhao Wenzheng

1984-01-01

The hematological changes of 2867 cases of medical X-ray workers and 1152 cases of non-X-ray medical workers were compared. It was shown that the total number of leukocytes, the numbers of neutrophils, lymphocytes and platelets were significantly lower in X-ray workers than those in controls. However, the percentages of monocytes, eosinophils, basophils and the concentration of hemoglobin were higher in the irradiated group. the difference between the two groups was statistically significant. The degree of changes in the number of blood cells was dose-dependent. A negative correlation could be found between the changes of leukocyte and neutrophil counts and cumulative dose (<250 mGy), annual dose (<15 mGy/a) and length of service of the X-ray workers; and a positive correlation existed between the percentages of basophils, eosinophils and monocytes, and the radiation dose. The abnormality rate of blood picture in the irradiated group was higher than that in the control group. Most X-ray workers with abnormal blood picture were distributed in low-dose group. The data also showed that radiation effect on male X-ray workers was greater than that on female workers. (Author)

A double-blind, randomized, multiple-dose, parallel-group study to characterize the occurrence of diarrhea following two different dosing regimens of neratinib, an irreversible pan-ErbB receptor tyrosine kinase inhibitor.

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Abbas, Richat; Hug, Bruce A; Leister, Cathie; Sonnichsen, Daryl

2012-07-01

Neratinib, a potent, low-molecular-weight, orally administered, irreversible, pan-ErbB receptor tyrosine kinase inhibitor has antitumor activity in ErbB2 + breast cancer. The objective of this study was to characterize the onset, severity, and duration of diarrhea after administration of neratinib 240 mg once daily (QD) and 120 mg twice daily (BID) for ≤14 days in healthy subjects. A randomized, double-blind, parallel-group, inpatient study was conducted in 50 subjects given oral neratinib either 240 mg QD or 120 mg BID with food for ≤14 days. The primary endpoint was the proportion of subjects with diarrhea of at least moderate severity (grade 2; 5-7 loose stools/day). In subjects with grade 2 diarrhea, fecal analytes were determined. Pharmacokinetic profiles were characterized for neratinib on Days 1 and 7. No severe (grade 3) diarrhea was reported. By Day 4, all subjects had grade 1 diarrhea. Grade 2 diarrhea occurred in 11/22 evaluable subjects (50 % [90 % confidence interval (CI): 28-72 %]) in the QD group and 17/23 evaluable subjects (74 % [90 % CI: 52-90 %]) in the BID group (P = 0.130). In fecal analyses, 18 % tested positive for hemoglobin and 46 % revealed fecal lactoferrin. Specimen pH was neutral to slightly alkaline. In pharmacokinetic analyses, Day 1 peak plasma concentration and Day 7 steady-state exposure were higher with the QD regimen than the BID regimen. In an exploratory analysis, ABCG2 genotype showed no correlation with severity or onset of diarrhea. Incidences and onsets of at least grade 1 and at least grade 2 diarrhea were not improved on BID dosing compared with QD dosing.

Work practices and occupational radiation dose among radiologic technologists in Korea

International Nuclear Information System (INIS)

Cha, Eun Shil; Lee, Won Jin; Ha, Mina; Hwang, Seung Sik; Lee, Kyoung Mu; Jeong, Mee Seon

2013-01-01

Radiologic technologists are one of the occupational groups exposed to the highest dose of radiation worldwide. In Korea, radiologic technologists occupy the largest group (about 33%) among medical radiation workers and they are exposed to the highest dose of occupational dose of radiation as well (1). Although work experience with diagnostic radiation procedure of U.S. radiologic technologists was reported roughly (2), few studies have been conducted for description of overall work practices and the change by calendar year and evaluation of related factors on occupational radiation dose. The aims of the study are to describe work practices and to assess risk factors for occupational radiation dose among radiologic technologists in Korea. This study showed the work practices and occupational radiation dose among representative sample of radiologic technologists in Korea. The annual effective dose among radiologic technologists in Korea remains higher compared with those of worldwide average and varied according to demographic factors, year began working, and duration of working

Comparison of fixed low dose versus high dose radioactive iodine for the treatment of hyperthyroidism: retrospective multifactorial analysis impacting the outcome of therapy

International Nuclear Information System (INIS)

Suresh Kumar, A.C.; Malhotra, G.; Basu, S.; Asopa, R.V.

2010-01-01

Full text: Radioactive iodine ( 131 I) as a fixed dose protocol is widely used for treatment of hyperthyroidism. However, there is no consensus on the best optimum dose for an individual patient. The objectives of this study were to observe the outcome of 131 I therapy in patients of primary hyperthyroidism in relation to fixed low dose versus high dose regimen, impact of antithyroid drugs and influence of thyroid gland size on therapy outcome. Materials and Methods: Study design: Retrospective analysis. Study group included 287 diagnosed patients of primary hyperthyroidism who had undergone 131 I therapy for the first time (68 M, 219 F; Mean age ± S.D.: 43.84 ± 12.53). All patients with low RAIU, thyrocardiac disease were excluded. Details of antithyroid (ATD) drug treatment were recorded. Analysis was done from 2002 till patients became euthyroid/hypothyroid or until January 2010. Each patient's response was evaluated initially at 6 weeks and thereafter every three months. Appropriate statistical tests were applied to compare treatment response between the groups. A P value<0.05 was considered significant. Results: Of 287 patients, 209 patients had been administered low dose (Mean ± S.D.: 4.68 ± 0.62 mCi) while 78 patients had received high dose (Mean ± S.D.: 9.15 ± 1.05 mCi) of radioiodine. 57.9% (121/ 209) patients in the low dose group responded as compared to 75.6% (59/78) in high dose group after a follow up of more than 36 months. Similarly, among patients with and without antithyroid drug treatment, grade II and above goiters the response rates were significantly higher for high dose group as compared to low dose group. Conclusion: We suggest that high dose radioiodine treatment with 8 to 10 mCi is effective in treating hyperthyroidism in patients with a better success rate than the low dose treatment with 3 to 5 mCi. This is also likely to be helpful in patients who have not received antithyroid drugs. It appears that clinically relevant

Dose calculation for photon-emitting brachytherapy sources with average energy higher than 50 keV: report of the AAPM and ESTRO.

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Perez-Calatayud, Jose; Ballester, Facundo; Das, Rupak K; Dewerd, Larry A; Ibbott, Geoffrey S; Meigooni, Ali S; Ouhib, Zoubir; Rivard, Mark J; Sloboda, Ron S; Williamson, Jeffrey F

2012-05-01

Recommendations of the American Association of Physicists in Medicine (AAPM) and the European Society for Radiotherapy and Oncology (ESTRO) on dose calculations for high-energy (average energy higher than 50 keV) photon-emitting brachytherapy sources are presented, including the physical characteristics of specific (192)Ir, (137)Cs, and (60)Co source models. This report has been prepared by the High Energy Brachytherapy Source Dosimetry (HEBD) Working Group. This report includes considerations in the application of the TG-43U1 formalism to high-energy photon-emitting sources with particular attention to phantom size effects, interpolation accuracy dependence on dose calculation grid size, and dosimetry parameter dependence on source active length. Consensus datasets for commercially available high-energy photon sources are provided, along with recommended methods for evaluating these datasets. Recommendations on dosimetry characterization methods, mainly using experimental procedures and Monte Carlo, are established and discussed. Also included are methodological recommendations on detector choice, detector energy response characterization and phantom materials, and measurement specification methodology. Uncertainty analyses are discussed and recommendations for high-energy sources without consensus datasets are given. Recommended consensus datasets for high-energy sources have been derived for sources that were commercially available as of January 2010. Data are presented according to the AAPM TG-43U1 formalism, with modified interpolation and extrapolation techniques of the AAPM TG-43U1S1 report for the 2D anisotropy function and radial dose function.

Effect of High-Dose vs Standard-Dose Wintertime Vitamin D Supplementation on Viral Upper Respiratory Tract Infections in Young Healthy Children.

Science.gov (United States)

Aglipay, Mary; Birken, Catherine S; Parkin, Patricia C; Loeb, Mark B; Thorpe, Kevin; Chen, Yang; Laupacis, Andreas; Mamdani, Muhammad; Macarthur, Colin; Hoch, Jeffrey S; Mazzulli, Tony; Maguire, Jonathon L

2017-07-18

Epidemiological studies support a link between low 25-hydroxyvitamin D levels and a higher risk of viral upper respiratory tract infections. However, whether winter supplementation of vitamin D reduces the risk among children is unknown. To determine whether high-dose vs standard-dose vitamin D supplementation reduces the incidence of wintertime upper respiratory tract infections in young children. A randomized clinical trial was conducted during the winter months between September 13, 2011, and June 30, 2015, among children aged 1 through 5 years enrolled in TARGet Kids!, a multisite primary care practice-based research network in Toronto, Ontario, Canada. Three hundred forty-nine participants were randomized to receive 2000 IU/d of vitamin D oral supplementation (high-dose group) vs 354 participants who were randomized to receive 400 IU/d (standard-dose group) for a minimum of 4 months between September and May. The primary outcome was the number of laboratory-confirmed viral upper respiratory tract infections based on parent-collected nasal swabs over the winter months. Secondary outcomes included the number of influenza infections, noninfluenza infections, parent-reported upper respiratory tract illnesses, time to first upper respiratory tract infection, and serum 25-hydroxyvitamin D levels at study termination. Among 703 participants who were randomized (mean age, 2.7 years, 57.7% boys), 699 (99.4%) completed the trial. The mean number of laboratory-confirmed upper respiratory tract infections per child was 1.05 (95% CI, 0.91-1.19) for the high-dose group and 1.03 (95% CI, 0.90-1.16) for the standard-dose group, for a between-group difference of 0.02 (95% CI, -0.17 to 0.21) per child. There was no statistically significant difference in number of laboratory-confirmed infections between groups (incidence rate ratio [RR], 0.97; 95% CI, 0.80-1.16). There was also no significant difference in the median time to the first laboratory-confirmed infection: 3.95 months

Long-term ingestion dose monitoring in a population group with increased 137Cs intake

International Nuclear Information System (INIS)

Bartuskova, M.; Lusnak, J.; Malatova, I.; Pfeiferova, V.; Pospisilova, H.

2008-01-01

137 Cs amounts and ingestion doses in Czech population have been monitored by whole-body counting since the Chernobyl accident. Indirect estimation of the retention through measurement of 137 Cs excreted with urine in 24 hours has also been performed since 1987. The 137 Cs content in human body can be calculated from the urine data provided that the intake of 137 Cs during the period of interest is constant. In a semi-natural environment, the 137 Cs content in mushrooms, wild berries and game decreases due to its natural decay solely. The 137 Cs content in people who mostly consume venison and have been living in an area with elevated contamination has been monitored, mostly through measurement of 137 Cs in urine. In parallel, measurements with a mobile whole-body counter have also been performed. Currently, annual doses from the ingestion of 137 Cs in the inhabitants are very low (0.001 to 0.002 mSv.year -1 ). In a group of hunters in the Jeseniky Mountains (Northern Moravia) the doses were estimated to 0.10 mSv.year -1 . (orig.)

Effects of low dose rate fission neutron irradiation on the lymphocyte subpopulations of peripheral blood in rats

International Nuclear Information System (INIS)

Jiang Dingwen; Lei Chengxiang; Shen Xianrong; Ma Li; Yang Yifang; Peng Wulin; Dai Shourong

2008-01-01

Objective: To evaluate the effects of long-term, low dose rate fission neutron irradiation on lymphocyte subpopulations in peripheral blood of rats. Methods: Ninety-six rats were randomly divided into control group and irradiated group exposed to low dose rate fission neutron ( 252 Cf,0.35 mGy/h) for 20.5 h every day. At days 14,28,42,56 and 70 d after irradiation and 35 d after stopping irradiation, After 8 rats of each group were killed, WBC and lymphocyte subpopulations of CD4 + CD3 + , CD8 + CD3 + and CD45RA + /CD161α + in peripheral blood were estimated respectively. Results: Compared with the control group, WBC was reduced significantly at dose of 0.3, 0.4 and 0.5 Gy (P + CD3 - was evidently higher compared with control group at doses of 0.1,0.3, 0.4 and 0.5 Gy and 35 d after stopping irradiation (P + CD3 - was obviously higher compared with control group at dose of 0.2 and 0.3 Gy (P + CD3 + at dose of 0.1 Gy (P + CD3 + at doses of 0.1 and 0.2 Gy (P + CD45RA - ) was increased significantly at doses of 0.2-0.3 Gy, and peripheral blood B cells(CD161α - CD45RA + ) was reduced remarkably at doses of 0.1-0.5 Gy and 35 d after stopping irradiation compared with the control group. Conclusions: Long-term irradiation with low dose rate fission neutron could make TCR (T-cell-receptor) mutant, therefore, WBC, B cells in peripheral blood significantly reduced and NK cells increased. These changes may could not recover at 35 d after Stopping irradiation. (authors)

Moderate- vs high-dose methadone in the treatment of opioid dependence: a randomized trial.

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Strain, E C; Bigelow, G E; Liebson, I A; Stitzer, M L

1999-03-17

Methadone hydrochloride treatment is the most common pharmacological intervention for opioid dependence, and recent interest has focused on expanding methadone treatment availability beyond traditional specially licensed clinics. However, despite recommendations regarding effective dosing of methadone, controlled clinical trials of higher-dose methadone have not been conducted. To compare the relative clinical efficacy of moderate- vs high-dose methadone in the treatment of opioid dependence. A 40-week randomized, double-blind clinical trial starting in June 1992 and ending in October 1995. Outpatient substance abuse treatment research clinic at the Johns Hopkins University Bayview Campus, Baltimore, Md. One hundred ninety-two eligible clinic patients. Daily oral methadone hydrochloride in the dose range of 40 to 50 mg (n = 97) or 80 to 100 mg (n = 95), with concurrent substance abuse counseling. Opioid-positive urinalysis results and retention in treatment. By intent-to-treat analysis through week 30 patients in the high-dose group had significantly lower rates of opioid-positive urine samples compared with patients in the moderate-dose group (53.0% [95% confidence interval [CI], 46.9%-59.2%] vs 61.9% [95% CI, 55.9%-68.0%]; P = .047. These differences persisted during withdrawal from methadone. Through day 210 no significant difference was evident between dose groups in treatment retention (high-dose group mean retention, 159 days; moderate-dose group mean retention, 157 days). Nineteen (33%) of 57 patients in the high-dose group and 11 (20%) of 54 patients in the moderate-dose group completed detoxification. Both moderate- and high-dose methadone treatment resulted in decreased illicit opioid use during methadone maintenance and detoxification. The high-dose group had significantly greater decreases in illicit opioid use.

Evaluation of skin entrance dose imparted on pediatric patients by thorax exams

International Nuclear Information System (INIS)

Oliveira, Mercia L.; Khoury, Helen; Drexler, Guenter; GSF-National Research Center for Environment and Health, Neuherberg; Barros, Edison

2001-01-01

In this work the results of a survey of skin entrance dose imparted on pediatric patients are present. Positioning the thermo luminescence dosimeters in contact with the patient's skin, in the center of the incident X-ray beam, collected the skin entrance dose data. The patients were grouped in five age groups: infants, 1,1 to 4 years, 4,1 to 6 years, 6,1 to 10 years and older than 10 years. The results show that the average of skin entrance doses is very higher as compared to the European Community Commission reference levels and to other values found in literature. (author)

The system for automatic dose rate measurements by mobile groups in field

International Nuclear Information System (INIS)

Drabova, D.; Filgas, R.; Cespirova, I.; Ejemova, M.

1998-01-01

The comparison of characteristics between a pressurized ionization chamber, plastic scintillator and proportional counter is given. Based on requirements and comparison of properties of various probes, the system for automatic dose rate measurement and integration of geographic co-ordinates in field was designed and tested.The system consists of proportional counter. This is so-called intelligent probe can be easily connected to a personal computer. The probe measures in the energy range 30 keV - 1.3 MeV with reasonable energy and angular response, it can measure the dose rate in the range 50 nSv/h - 1 Sv/h with the typical efficiency 9.5 imp/s/μSv/h. The probe is fixed in the holder placed on the front mask of a car. For the simultaneous determination of geographical co-ordinates the personal GPS navigator Garmin 95 is used. Both devices are controlled by a notebook via two serial ports. The second serial port that is not quite common in notebook can be easily realised by a PCMCIA card. The notebook is used in the field by a mobile group can be transmitted to the assessment centre by the cellular GSM phone. The system Nokia 2110 connected to notebook by PCMCIA card is used. The whole system is powered up from the car battery. The system is controlled by specially developed software. The software was developed in the FoxPro 2.5 environment and works under MS-DOS 6.22. It has no problems to work in Windows 95 DOS window. The results of dose rate measurements obtained during route monitoring are stored in files. They can be displayed on a graphic screen, presenting the geographical distribution of the dose rate values colour coded on a map and the time sequence of the measured data. (authors)

Which dose of bevacizumab is more effective for the treatment of aggressive posterior retinopathy of prematurity: lower or higher dose?

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Seyhan Dikci

Full Text Available ABSTRACT Purpose: To compare 0.5 mg and 0.625 mg of bevacizumab for treating aggressive posterior retinopathy of prematurity (AP-ROP. Methods: The medical records of patients with AP-ROP who were administered intravitreal bevacizumab (IVB as a primary treatment at a university clinic were evaluated retrospectively. Five eyes of three patients (Group 1 who received 0.625 mg/0.025 ml IVB and 10 eyes of another five patients (Group 2 who received 0.5 mg/0.02 ml IVB were evaluated. Laser photocoagulation was used as additional treatment after relapses. Anatomic results and complications were evaluated in both groups. Results: We evaluated 15 eyes of eight patients (four girls and four boys with a flat demarcation line at posterior zone 2 and plus disease or stage-3 disease in this study. The mean gestational age of the three babies in Group 1 was 26 ± 1 weeks and the mean birth weight was 835.33 ± 48.01 g. The corresponding values were 25.2 ± 1.6 weeks and 724 ± 139.03 g, respectively, for the five babies in Group 2. Retinal vascularization was completed at a mean postmenstrual duration of 53.6 ± 1.5 weeks without additional treatment in the five eyes in Group 1. Laser photocoagulation for relapse was administered to five of the 10 eyes in Group 2. Retinal vascularization was completed at a mean postmenstrual duration of 47.6 ± 1.5 weeks in the remaining five eyes. None of the patients developed complications such as cataract, glaucoma, retinal tear, retinal or vitreous hemorrhage, or retinal detachment. Conclusion: Although lower IVB doses in the treatment of AP-ROP are expected to be safer in terms of local and systemic side effects in premature infants, these patients may require additional treatment with IVB or laser photocoagulation.

Clinical outcome of one-third-dose depot triptorelin is the same as half-dose depot triptorelin in the long protocol of controlled ovarian stimulation

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Yu Li

2012-01-01

Full Text Available Objective: Appropriate dosage of the long-acting depot gonadotrophin releasing hormone (GnRH agonist has not been determined in long protocol for IVF, and one-third-dose depot triptorelin was compared with half-dose in a luteal long protocol of in-vitro fertilization/ intra cytoplasmic sperm injection (IVF/ICSI treatment in this study. Materials and Methods: This is a prospective, randomized, open clinical trial. 100 patients were randomized into two groups. Group I received one-third-dose (1.25 mg depot triptorelin. Group II received half-dose (1.87 mg. The clinical and experimental parameters were compared between the two groups. Results: There was no premature luteinizing hormone (LH surge in both groups. On Day 3-5 of menstrual cycle after down-regulation, fewer patients showed low-level LH (<1.0 IU/L and estradiol (<30 pg/mL in group I (P <0.05. There were fewer oocytes retrieved (P =0.086, fewer total embryos and available embryos for cryopreservation in Group I (P <0.05, while good-quality embryo rate was higher in group I (P <0.05. The length and dose of ovarian stimulation was lower in Group I, but not significantly. The clinical pregnancy (52% versus 40%, implantation (48% versus 37.5%, delivery (46% versus 32%, or live birth (42% versus 32% rates and the abortion (8% versus 20% rates showed no significant differences. Conclusion: Depot triptorelin 1.25 mg can be successfully used with reduced pituitary suppression and lower cost in a long protocol for in-vitro fertilization.

A randomized controlled trial of vitamin D dosing strategies after acute hip fracture: No advantage of loading doses over daily supplementation

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Farrauto Leonardo

2011-06-01

Full Text Available Abstract Background There remains uncertainty regarding the appropriate therapeutic management of hip fracture patients. The primary aim of our study was to examine whether large loading doses in addition to daily vitamin D offered any advantage over a simple daily low-dose vitamin D regimen for increasing vitamin D levels. Methods In this randomized controlled study, patients over age 50 with an acute fragility hip fracture were enrolled from two hospital sites in Ontario, Canada. Participants were randomized to one of three loading dose groups: placebo; 50,000 IU vitamin D2; or 100,000 IU D2. Following a placebo/loading dose, all patients received a daily tablet of 1,000 IU vitamin D3 for 90 days. Serum 25-hydroxy vitamin D (25-OHD was measured at baseline, discharge from acute care (approximately 4-weeks, and 3-months. Results Sixty-five patients were enrolled in the study (44% male. An immediate rise in 25-OHD occurred in the 100,000 group, however there were no significant differences in 25-OHD between the placebo, 50,000 and 100,000 loading dose groups after 4-weeks (69.3, 84.5, 75.6 nmol/L, p = 0.15 and 3-months (86.7, 84.2, 73.3 nmol/L, p = 0.09, respectively. At the end of the study, approximately 75% of the placebo and 50,000 groups had reached the target therapeutic range (75 nmol/L, and 44% of the 100,000 group. Conclusions In correcting vitamin D insufficiency/deficiency in elderly patients with hip fracture, our findings suggest that starting with a lower daily dose of Vitamin D3 achieved similar results as providing an additional large loading dose of Vitamin D2. At the end of the study, all three groups were equally effective in attaining improvement in 25-OHD levels. Given that a daily dose of 1,000 IU vitamin D3 (with or without a loading dose resulted in at least 25% of patients having suboptimal vitamin D status, patients with acute hip fracture may benefit from a higher daily dose of vitamin D. Trial registration Clinical

Nominal Group Technique and its Applications in Managing Quality in Higher Education

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Rafikul Islam

2011-09-01

Full Text Available Quality management is an important aspect in all kinds of businesses – manufacturing or service. Idea generation plays a pivotal role in managing quality in organizations. It is thenew and innovative ideas which can help corporations to survive in the turbulent business environment. Research in group dynamics has shown that more ideas are generated by individuals working alone but in a group environment than the individuals engaged in a formal group discussion. In Nominal Group Technique (NGT, individuals work alone but in a group setting. This paper shows how NGT can be applied to generate large number of ideas to solve quality related problems specifically in Malaysian higher education setting. The paper also discusses the details of NGT working procedure andexplores the areas of its further applications.

Propofol for pediatric tracheal intubation with deep anesthesia during sevoflurane induction: dosing according to elapsed time for two age groups.

Science.gov (United States)

Politis, George D; Stemland, Christopher J; Balireddy, Ravi K; Brockhaus, Julie; Hughes, Kevin R; Goins, Matthew D; McMurry, Timothy L

2014-02-01

To determine, for two different age groups, the effect of duration of sevoflurane administration on the amount of propofol needed when performing tracheal intubation. Classic Dixon's Up-and-Down sequential method. University based operating rooms. 106 ASA physical status 1 and 2 patients aged one to 11 years. Patients were allocated to the 1-6 year (≥ 12 and age groups. Midazolam 0.5 mg/kg was given orally to the 1-6 year group, and all patients were induced with 8% dialed sevoflurane and 67% nitrous oxide (N2O), with N2O discontinued and sevoflurane dialed to 5% after one minute and 1.5 minutes for the younger and older age groups, respectively. Intravenous access was obtained and propofol was promptly administered. Propofol dose was determined according to age group and whether propofol was given 2-4, 4-6, or 6-8 minutes after the start of sevoflurane induction, with Dixon's Up and Down Method used separately for each specific age/time group. Tracheal intubation conditions one minute after propofol were evaluated. Isotonic regression determined propofol ED50 estimates for excellent tracheal intubation conditions, and linear regression determined the effect of propofol dose on change in systolic blood pressure (SBP). Estimated propofol ED50 doses for 1-6 year olds, with 95% confidence intervals (CIs), were 1.48 mg/kg (0.80, 2.03), 0.00 mg/kg (0.00, 0.38), and 0.07 mg/kg (0.00, 0.68) in the 2-4, 4-6, and 6-8 minute groups, respectively, with estimated differences between the 2-4 minute group versus the 4-6 and 6-8 minute groups being 1.47 mg/kg (95% CI = 1.04, 2.06) and 1.41 mg/kg (95% CI = 0.74, 2.04), respectively. Estimated propofol ED50 doses for 6-11 year olds, with 95% CIs, were 2.35 mg/kg (1.97, 2.45) and 2.33 mg/kg (1.59, 2.45) in the 2-4 and 4-6 minute groups, respectively. Diminutions in SBP at one minute and two minutes after propofol administration were dose dependent for children 1-6 years of age, decreasing 5.3% and 8.1% for each 1 mg/kg of propofol

Cardiovascular disease and ABO blood-groups in Africans. Are blood-group A individuals at higher risk of ischemic disease?: A pilot study.

Science.gov (United States)

Ba, Djibril Marie; Sow, Mamadou Saidou; Diack, Aminata; Dia, Khadidiatou; Mboup, Mouhamed Cherif; Fall, Pape Diadie; Fall, Moussa Daouda

2017-12-01

Since the discovery of the ABO blood group system by Karl Landsteiner in 1901, several reports have suggested an important involvement of the ABO blood group system in the susceptibility to thrombosis. Assessing that non-O blood groups in particular A blood group confer a higher risk of venous and arterial thrombosis than group O.Epidemiologic data are typically not available for all racial and ethnics groups.The purpose of this pilot study was to identify a link between ABO blood group and ischemic disease (ID) in Africans, and to analyze whether A blood group individuals were at higher risk of ischemic disease or not. A total of 299 medical records of patients over a three-year period admitted to the cardiology and internal medicine department of military hospital of Ouakam in Senegal were reviewed. We studied data on age, gender, past history of hypertension, diabetes, smoking, sedentarism, obesity, hyperlipidemia, use of estrogen-progestin contraceptives and blood group distribution.In each blood group type, we evaluated the prevalence of ischemic and non-ischemic cardiovascular disease. The medical records were then stratified into two categories to evaluate incidence of ischemic disease: Group 1: Patients carrying blood-group A and Group 2: Patients carrying blood group non-A (O, AB and B). Of the 299 patients whose medical records were reviewed, 92 (30.8%) were carrying blood group A, 175 (58.5%) had blood group O, 13 (4.3%) had blood group B, and 19 (6.4%) had blood group AB.The diagnosis of ischemic disease (ID) was higher in patients with blood group A (61.2%) than in other blood groups, and the diagnosis of non-ischemic disease (NID) was higher in patients with blood group O (73.6%) compared to other groups. In patients with blood group B or AB compared to non-B or non-AB, respectively there was no statistically significant difference in ID incidence.Main risk factor for ID was smoking (56.5%), hypertension (18.4%) and diabetes (14.3%).In our study

Work management practices that reduce dose and improve efficiency

International Nuclear Information System (INIS)

Miller, D.W.; Hulin, M.

1998-01-01

Work management practices at nuclear power plants can dramatically affect the outcome of annual site dose goals and outage costs. This presentation discusses global work management practices that contribute to dose reduction including work philosophy, work selection, work planning, work scheduling, worker training, work implementation and worker feedback. The presentation is based on a two-year international effort (sponsored by NEA/IAEA ISOE) to study effective work practices that reduce dose. Experts in this area believe that effective work selection and planning practices can substantially reduce occupational dose during refueling outages. For example, some plants represented in the expert group complete refueling outages in 12-18 days (Finland) with doses below 0,90 person-Sv. Other plants typically have 50-75 day outages with substantially higher site doses. The fundamental reasons for longer outages and higher occupational doses are examined. Good work management principles that have a proven track record of reducing occupational dose are summarized. Practical methods to reduce work duration and dose are explained. For example, scheduling at nuclear power plants can be improved by not only sequencing jobs on a time line but also including zone and resource-based considerations to avoid zone congestion and manpower delays. An ongoing, global, benchmarking effort is described which provides current duration and dose information for repetitive jobs to participating utilities world-wide. (author)

Direct dosing of preweaning rodents in toxicity testing and research: deliberations of an ILSI RSI Expert Working Group.

Science.gov (United States)

Moser, Virginia C; Walls, Isabel; Zoetis, Tracey

2005-01-01

Laboratory animal studies designed to assess the effects of exposure of a test substance during postnatal development are commonly utilized in basic research and to evaluate potential hazard to children for chemical and pharmaceutical regulation. Direct dosing, defined here as the administration of a test substance directly to a preweaning mammal, has been identified as a useful tool that can be used in the conduct of such studies for regulatory purposes. The International Life Sciences Institute Risk Science Institute (ILSI RSI) convened an Expert Working Group to develop guidance on the design and implementation of direct dosing regulatory studies on preweaning mammals, which was published as an ILSI monograph in 2003 (Zoetis and Walls, Principles and Practices for Direct Dosing of Pre-Weaning Mammals in Toxicity Testing and Research, Washington, DC: ILSI Press, 2003). A summary of the Working Group conclusions regarding direct dosing studies with laboratory rodents are presented here, although the ILSI monograph also includes rabbits, canines, swine and nonhuman primates. Issues to be considered when designing the protocol include selection of the test species, the route of administration, dose levels, and the timing of dosing. Knowledge of the maturational status of the test species and information on critical windows of development are important in creating a valid study design. Most common routes of administration (e.g., oral, inhalation, injection) are possible with typical laboratory species; however, adjustments may be necessary due to practical considerations. Information on the pharmacokinetic profile in young animals versus adults and in the test species versus humans is very useful for determining dosing parameters. The conduct of the study and the interpretation of the data will be improved by an understanding of confounding factors as well as statistical and biological issues specific for postnatal studies. Ultimately, the success of the study will

IAEA advisory group meeting on dosimetry for high doses employed in industrial radiation processing, Vienna, 17-21 November 1980

International Nuclear Information System (INIS)

Chadwick, K.H.

1981-01-01

In 1977 the IAEA established a programme on High-Dose Standardization and Intercomparison with the aim of developing a world-wide service for dosimetry assurance in Industrial and Research Radiation Processing Facilities. The complete proceedings of the first Advisory Group meeting held within this programme have recently been published in the IAEA Technical Reports Series (No. 205) under the title ''High-Dose Measurement in Industrial Radiation Processing''. This report of the second Advisory Group meeting provides a brief review of the state of the programme at the present time. (The full proceedings of the meeting will not be published)

Spine stereotactic body radiation therapy plans: Achieving dose coverage, conformity, and dose falloff

International Nuclear Information System (INIS)

Hong, Linda X.; Shankar, Viswanathan; Shen, Jin; Kuo, Hsiang-Chi; Mynampati, Dinesh; Yaparpalvi, Ravindra; Goddard, Lee; Basavatia, Amar; Fox, Jana; Garg, Madhur; Kalnicki, Shalom; Tomé, Wolfgang A.

2015-01-01

We report our experience of establishing planning objectives to achieve dose coverage, conformity, and dose falloff for spine stereotactic body radiation therapy (SBRT) plans. Patients with spine lesions were treated using SBRT in our institution since September 2009. Since September 2011, we established the following planning objectives for our SBRT spine plans in addition to the cord dose constraints: (1) dose coverage—prescription dose (PD) to cover at least 95% planning target volume (PTV) and 90% PD to cover at least 99% PTV; (2) conformity index (CI)—ratio of prescription isodose volume (PIV) to the PTV < 1.2; (3) dose falloff—ratio of 50% PIV to the PTV (R 50% ); (4) and maximum dose in percentage of PD at 2 cm from PTV in any direction (D 2cm ) to follow Radiation Therapy Oncology Group (RTOG) 0915. We have retrospectively reviewed 66 separate spine lesions treated between September 2009 and December 2012 (31 treated before September 2011 [group 1] and 35 treated after [group 2]). The χ 2 test was used to examine the difference in parameters between groups. The PTV V 100% PD ≥ 95% objective was met in 29.0% of group 1 vs 91.4% of group 2 (p < 0.01) plans. The PTV V 90% PD ≥ 99% objective was met in 38.7% of group 1 vs 88.6% of group 2 (p < 0.01) plans. Overall, 4 plans in group 1 had CI > 1.2 vs none in group 2 (p = 0.04). For D 2cm , 48.3% plans yielded a minor violation of the objectives and 16.1% a major violation for group 1, whereas 17.1% exhibited a minor violation and 2.9% a major violation for group 2 (p < 0.01). Spine SBRT plans can be improved on dose coverage, conformity, and dose falloff employing a combination of RTOG spine and lung SBRT protocol planning objectives

Spine stereotactic body radiation therapy plans: Achieving dose coverage, conformity, and dose falloff

Energy Technology Data Exchange (ETDEWEB)

Hong, Linda X., E-mail: lhong0812@gmail.com [Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY (United States); Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, NY (United States); Shankar, Viswanathan [Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, NY (United States); Shen, Jin [Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY (United States); Kuo, Hsiang-Chi [Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY (United States); Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, NY (United States); Mynampati, Dinesh [Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY (United States); Yaparpalvi, Ravindra [Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY (United States); Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, NY (United States); Goddard, Lee [Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY (United States); Basavatia, Amar; Fox, Jana; Garg, Madhur; Kalnicki, Shalom; Tomé, Wolfgang A. [Department of Radiation Oncology, Montefiore Medical Center, Bronx, NY (United States); Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, NY (United States)

2015-10-01

We report our experience of establishing planning objectives to achieve dose coverage, conformity, and dose falloff for spine stereotactic body radiation therapy (SBRT) plans. Patients with spine lesions were treated using SBRT in our institution since September 2009. Since September 2011, we established the following planning objectives for our SBRT spine plans in addition to the cord dose constraints: (1) dose coverage—prescription dose (PD) to cover at least 95% planning target volume (PTV) and 90% PD to cover at least 99% PTV; (2) conformity index (CI)—ratio of prescription isodose volume (PIV) to the PTV < 1.2; (3) dose falloff—ratio of 50% PIV to the PTV (R{sub 50%}); (4) and maximum dose in percentage of PD at 2 cm from PTV in any direction (D{sub 2cm}) to follow Radiation Therapy Oncology Group (RTOG) 0915. We have retrospectively reviewed 66 separate spine lesions treated between September 2009 and December 2012 (31 treated before September 2011 [group 1] and 35 treated after [group 2]). The χ{sup 2} test was used to examine the difference in parameters between groups. The PTV V{sub 100%} {sub PD} ≥ 95% objective was met in 29.0% of group 1 vs 91.4% of group 2 (p < 0.01) plans. The PTV V{sub 90%} {sub PD} ≥ 99% objective was met in 38.7% of group 1 vs 88.6% of group 2 (p < 0.01) plans. Overall, 4 plans in group 1 had CI > 1.2 vs none in group 2 (p = 0.04). For D{sub 2cm}, 48.3% plans yielded a minor violation of the objectives and 16.1% a major violation for group 1, whereas 17.1% exhibited a minor violation and 2.9% a major violation for group 2 (p < 0.01). Spine SBRT plans can be improved on dose coverage, conformity, and dose falloff employing a combination of RTOG spine and lung SBRT protocol planning objectives.

The history of critical group doses from the consumption of freshwater fish at Trawsfynydd, North Wales

International Nuclear Information System (INIS)

Leonard, D.R.P.

1992-01-01

Radionuclides discharged into the aquatic environment from Trawsfynydd power station are, as for all UK facilities, subject to statutory controls to ensure that the resulting public radiation exposure complies with nationally-accepted criteria. Environmental monitoring by MAFF has shown that near this facility the consumption of freshwater fish is radiologically the most important pathway with Cs-137 the dominant radionuclide. Information gathered from consumers over a twenty-five year period has been interpreted so as to derive doses to the public. Committed effective doses (CEDs) are presented using ICRP 1990 methodology and compared with the recommended dose limit of 1 mSv year -1 . Doses to the critical group are shown to have exceeded 1 mSv year -1 for two years but do not exceed this limit when averaged over a period of 5 years. Because of the changing habits of the consumers it is suggested that the average annual CED over the lifetime of any member of the public will not exceed 1 mSv year -1 during the operation of the station. (author)

Efficacy and safety of budesonide/formoterol single inhaler therapy versus a higher dose of budesonide in moderate to severe asthma

NARCIS (Netherlands)

Scicchitano, R; Aalbers, R; Ukena, D; Manjra, A; Fouquert, L; Centanni, S; Boulet, LP; Naya, IP; Hultquist, C

Objectives:This study evaluated the efficacy and safety of a novel asthma management strategy - budesonide/formoterol for both maintenance and symptom relief (Symbicort Single Inhaler Therapy*) - compared with a higher maintenance dose of budesonide in patients with moderate to severe asthma.

Cost reduction in abdominal CT by weight-adjusted dose

International Nuclear Information System (INIS)

Arana, Estanislao; Marti-Bonmati, Luis; Tobarra, Eva; Sierra, Consuelo

2009-01-01

Aim: To analyze the influence of contrast dose adjusted by weight vs. fixed contrast dose in the attenuation and cost of abdominal computed tomography (CT). Materials and methods: A randomised, consecutive, parallel group study was conducted in 151 patients (74 men and 77 women, age range 22-67 years), studied with the same CT helical protocol. A dose at 1.75 ml/kg was administered in 101 patients while 50 patients had a fixed dose of 120 ml of same non-ionic contrast material (320 mg/ml). Mean enhancements were measured at right hepatic lobe, superior abdominal aorta and inferior cava vein. Statistical analysis was weight-stratified ( 81 kg). Results: Aortic attenuation was significantly superior (p 61 kg in dose-adjusted group, presented higher hepatic attenuation, being statistically significant in those >81 kg (p 80 kg, there was an over cost of Euro 10.7 per patient. Conclusions: An injection volume of 1.75 ml/kg offers an optimal diagnostic quality with a global savings of Euro 1.34 per patient.

Low dose radiation enhance the anti-tumor effect of high dose radiation on human glioma cell U251

International Nuclear Information System (INIS)

Wang Chang; Wang Guanjun; Tan Yehui; Jiang Hongyu; Li Wei

2008-01-01

Objective: To detect the effect on the growth of human glioma cell U251 induced by low dose irradiation and low dose irradiation combined with large dose irradiation. Methods: Human glioma cell line U251 and nude mice carried with human glioma were used. The tumor cells and the mice were treated with low dose, high dose, and low dose combined high dose radiation. Cells growth curve, MTT and flow cytometry were used to detect the proliferation, cell cycle and apoptosis of the cells; and the tumor inhibition rate was used to assess the growth of tumor in vivo. Results: After low dose irradiation, there was no difference between experimental group and control group in cell count, MTT and flow cytometry. Single high dose group and low dose combined high dose group both show significantly the suppressing effect on tumor cells, the apoptosis increased and there was cell cycle blocked in G 2 period, but there was no difference between two groups. In vivo apparent anti-tumor effect in high dose radiation group and the combining group was observed, and that was more significant in the combining group; the prior low dose radiation alleviated the injury of hematological system. There was no difference between single low dose radiation group and control. Conclusions: There is no significant effect on human glioma cell induced by low dose radiation, and low dose radiation could not induce adaptive response. But in vivo experience, low dose radiation could enhance the anti-tumor effect of high dose radiation and alleviated the injury of hematological system. (authors)

Radiation dose from Chernobyl forests: assessment using the 'forestpath' model

International Nuclear Information System (INIS)

Schell, W.R.; Linkov, I.; Belinkaia, E.; Rimkevich, V.; Zmushko, Yu.; Lutsko, A.; Fifield, F.W.; Flowers, A.G.; Wells, G.

1996-01-01

Contaminated forests can contribute significantly to human radiation dose for a few decades after initial contamination. Exposure occurs through harvesting the trees, manufacture and use of forest products for construction materials and paper production, and the consumption of food harvested from forests. Certain groups of the population, such as wild animal hunters and harvesters of berries, herbs and mushrooms, can have particularly large intakes of radionuclides from natural food products. Forestry workers have been found to receive radiation doses several times higher than other groups in the same area. The generic radionuclide cycling model 'forestpath' is being applied to evaluate the human radiation dose and risks to population groups resulting from living and working near the contaminated forests. The model enables calculations to be made to predict the internal and external radiation doses at specific times following the accident. The model can be easily adjusted for dose calculations from other contamination scenarios (such as radionuclide deposition at a low and constant rate as well as complex deposition patterns). Experimental data collected in the forests of Southern Belarus are presented. These data, together with the results of epidemiological studies, are used for model calibration and validation

Sustained availability of trimethoprim in drinking water to achieve higher plasma sulphonamide-trimethoprim antibacterial activity in broilers.

Science.gov (United States)

Sumano, H; Hernandez, L; Gutierrez, L; Bernad-Bernad, M J

2005-02-01

(1) In order to make trimethoprim (TMP) available to broilers throughout the day, a sustained release formulation (SRF) of the drug in the form of granules was added to the water tank that supplies drinking water. (2) Broilers were initially dosed with sulphachloropiridazine-TMP (SCP-TMP 5:1) and then further medicated throughout the day, achieving in the end a dose of 30 mg/kg each of SCP and TMP (group A). Group B received a preparation with the same dose of SCP and TMP (1:1) as group A, but administered as a single dose without the SRF of TMP. Group C received the customary SCP-TMP 5:1 preparation (30 and 6 mg/kg, respectively). Water tanks were completely consumed in 3 to 4 h. (3) Broilers were bled at different times and concentration of antibacterial activity in serum determined by correlating the composite antibacterial activity of SCP and TMP with actual concentrations of these drugs by means of a microbiological agar diffusion assay. (4) Time vs serum concentrations of activity were higher in group B; the increments in the maximum serum concentration for group B over groups A and C being 39 and 67%, respectively. (5) However, the sustained concentration of activity over time, measured as the area under the cu)rve, was highest in group A. Group B had higher values for area under the curve than group C. (6) An additional dose of TMP to achieve 30 mg/kg of both SCP and TMP improves the serum concentration of this combination over the customary 5:1 proportion. The best values for sustaining antibacterial activity were obtained using a 1:1 ratio as in group A. The use of a SRF as in group A may translate into better clinical results.

Dose specification for radiation therapy: dose to water or dose to medium?

International Nuclear Information System (INIS)

Ma, C-M; Li Jinsheng

2011-01-01

The Monte Carlo method enables accurate dose calculation for radiation therapy treatment planning and has been implemented in some commercial treatment planning systems. Unlike conventional dose calculation algorithms that provide patient dose information in terms of dose to water with variable electron density, the Monte Carlo method calculates the energy deposition in different media and expresses dose to a medium. This paper discusses the differences in dose calculated using water with different electron densities and that calculated for different biological media and the clinical issues on dose specification including dose prescription and plan evaluation using dose to water and dose to medium. We will demonstrate that conventional photon dose calculation algorithms compute doses similar to those simulated by Monte Carlo using water with different electron densities, which are close (<4% differences) to doses to media but significantly different (up to 11%) from doses to water converted from doses to media following American Association of Physicists in Medicine (AAPM) Task Group 105 recommendations. Our results suggest that for consistency with previous radiation therapy experience Monte Carlo photon algorithms report dose to medium for radiotherapy dose prescription, treatment plan evaluation and treatment outcome analysis.

Comparison of ESD and major organ absorbed doses of 5 year old standard guidekines and clinical exposure conditions

Energy Technology Data Exchange (ETDEWEB)

Kang, A Ram; Ahn, Sung Min [Dept. of Radiological Science, The Graduate School, Gachon University, Incheon (Korea, Republic of); Lee, In Ja [Dept. of Radiologic technology, Dongnam health University, Suwon (Korea, Republic of)

2017-09-15

Pediatrics are more sensibility to radiation than adults and because they are organs that are not completely grown, they have a life expectancy that can be adversely affected by exposure. Therefore, the management of exposure dose is more important than the case of adult. The purpose of this study was to determine the suitability of the 10 year old phantom for the 5 year old pediatric's recommendation and the incident surface dose, and to measure the organ absorbed dose. This study is compared the organ absorbed dose and the entrance surface dose in the clinical conditions at 5 and 10 years old pediatric. Clinical 5 year old condition was slightly higher than recommendation condition and 10 year old condition was very high. In addition, recommendation condition ESD was found to be 43% higher than the ESD of the 5 year old group and the ESD of the 10 year old group was 126% higher than that of the 5 year old group. The recommended ESD at 5 years old and the ESD according to clinical imaging conditions were 31.6%. There was no significant difference between the 5 year old recommended exposure conditions and the organ absorbed dose due to clinical exposure conditions, but there was a large difference between the Chest and Pelvic. However, it was found that there was a remarkable difference when comparing the organ absorbed dose by 10 year clinical exposure conditions. Therefore, more detailed standard exposure dose for the recommended dose of pediatric should be studied.

Comparison of ESD and major organ absorbed doses of 5 year old standard guidekines and clinical exposure conditions

International Nuclear Information System (INIS)

Kang, A Ram; Ahn, Sung Min; Lee, In Ja

2017-01-01

Pediatrics are more sensibility to radiation than adults and because they are organs that are not completely grown, they have a life expectancy that can be adversely affected by exposure. Therefore, the management of exposure dose is more important than the case of adult. The purpose of this study was to determine the suitability of the 10 year old phantom for the 5 year old pediatric's recommendation and the incident surface dose, and to measure the organ absorbed dose. This study is compared the organ absorbed dose and the entrance surface dose in the clinical conditions at 5 and 10 years old pediatric. Clinical 5 year old condition was slightly higher than recommendation condition and 10 year old condition was very high. In addition, recommendation condition ESD was found to be 43% higher than the ESD of the 5 year old group and the ESD of the 10 year old group was 126% higher than that of the 5 year old group. The recommended ESD at 5 years old and the ESD according to clinical imaging conditions were 31.6%. There was no significant difference between the 5 year old recommended exposure conditions and the organ absorbed dose due to clinical exposure conditions, but there was a large difference between the Chest and Pelvic. However, it was found that there was a remarkable difference when comparing the organ absorbed dose by 10 year clinical exposure conditions. Therefore, more detailed standard exposure dose for the recommended dose of pediatric should be studied

Dose due to man-made radionuclides in terrestrial wild foods near Sellafield

International Nuclear Information System (INIS)

Fulker, M.J.; Jackson, D.; McKay, K.; John, C.; Leonard, D.R.P.

1998-01-01

Radiological dose implications for consumers of wild foods around Sellafield have been assessed. Habits were surveyed from 72 households, mostly within a few kilometres of Sellafield. A few people were included who lived further away but collect wild foods close to Sellafield. Dose estimates were based on measured gamma emitters, as well as 239 Pu, 241 Am, 14 C and 129 I in selected samples. In all cases, doses were dominated by 137 Cs. One infant was identified who consumed wild food, giving an estimated effective dose of 0.3 μSv a -1 . In the age group 2 to 10 years a mean dose of 0.51 μSv a -1 , and a maximum of 2.8 μSv a -1 , were estimated. Intakes by adults were higher and resulted in more radiologically significant doses. The extreme individual received a dose of 32 μSv a -1 largely due to consumption of honey that included contributions from the Chernobyl accident, and hedgerow fruits. This is comparable to doses to the critical group for consumption of conventional agricultural produce close to the Sellafield site. The 97.5th percentile dose, for all age groups of consumers taken together, was 16.6 μSv a -1 , or 6.2 μSv a -1 if the contributions from Chernobyl are excluded. Considering the contributions from different foods to the whole group of 181 wild food consumers, the rank order is honey, blackberries and venison. (author)

Assessment of the effective supplementary doses for people belonging to a critical group placed nearby an uranium mining zone

International Nuclear Information System (INIS)

Aurelian, Florian; Popescu, Mihai; Georgescu, Dan

2008-01-01

Full text: The paper presents a case study concerning the impact on environment and population of a exploration uranium mining area. The paper is structured on three levels and presents: First stage will consist of the investigation and characterization of the sources, respectively the transfer pathways: terrestrial, aerial and aquatic ones followed by the assessment of the effective supplementary doses received by the people of population through all the transfer pathways based on some scenarios according to which their presence was permanent or temporary. Second stage concerns the assessment of the supplementary effective doses for the working staff during the caring out the closing workings. There are references concerning the monitoring 'of rehabilitation' during the time when the disaffection workings are ongoing beside the survey of the professional exposed people and the calculation of the supplementary doses for people of population and the ones belonging to the critical group during the disaffection time. Within the third stage framework there are calculated, described and discussed the individual and collective effective doses for people belonging to the population and to the critical groups, which it is expected to be recorded after the disaffection works cessation. The last part of the paper focuses on the long-term miniaturization of the environmental factors following the disaffection works conclusion and on the long-term evolution of the supplementary doses as well. (author)

Comparative pharmacokinetics and bioavailability of albendazole sulfoxide in sheep and goats, and dose-dependent plasma disposition in goats.

Science.gov (United States)

Aksit, Dilek; Yalinkilinc, Hande Sultan; Sekkin, Selim; Boyacioğlu, Murat; Cirak, Veli Yilgor; Ayaz, Erol; Gokbulut, Cengiz

2015-05-27

The aims of this study were to compare the pharmacokinetics of albendazole sulfoxide (ABZ-SO, ricobendazole) in goats and sheep at a dose of 5 g/kg bodyweight (BW), after intravenous (IV) and subcutaneous (SC) administrations, and to investigate the effects of increased doses (10 and 15 mg/kg BW) on the plasma disposition of ABZ-SO in goats following SC administration. A total of 16 goats (Capra aegagrus hircus, eight males and eight females) and 8 sheep (Ovis aries, four males and four females) 12-16 months old and weighing 20-32 kg, were used. The study was designed according to two-phase crossover study protocol. In Phase-1, eight sheep were assigned as Group I and 16 goats were allocated into two groups (Group II and Group III). ABZ-SO was applied to Group I (sheep) and Group II (goats) animals subcutaneously, and to Group III (goats) animals intravenously, all at a dose rate of 5 mg/kg BW. In Phase-2, the sheep in the Group I received ABZ-SO intravenously in a dose of 5 mg/kg BW; the goats in Group II and Group III received ABZ-SO subcutaneously at a dose of 10 mg/kg and 15 mg/kg BW, respectively. Blood samples were collected from the jugular vein at different times between 1 and 120 h after drug administrations. The plasma concentrations of ABZ-SO and its metabolites were analysed by high performance liquid chromatography. In goats, the area under the curve, terminal half-life and plasma persistence of ABZ-SO were significantly smaller and shorter, respectively, compared with those observed in sheep following both IV and SC administrations at a dose of 5 mg/kg BW. On the other side, dose-dependent plasma dispositions of ABZ-SO were observed following SC administration at increased doses (10 and 15 mg/kg) in goats. Consequently, ABZ-SO might be used at higher doses to provide higher plasma concentration and thus to achieve greater efficacy against the target parasites.

Incorporating social groups' responses in a descriptive model for second- and higher-order impact identification

International Nuclear Information System (INIS)

Sutheerawatthana, Pitch; Minato, Takayuki

2010-01-01

The response of a social group is a missing element in the formal impact assessment model. Previous discussion of the involvement of social groups in an intervention has mainly focused on the formation of the intervention. This article discusses the involvement of social groups in a different way. A descriptive model is proposed by incorporating a social group's response into the concept of second- and higher-order effects. The model is developed based on a cause-effect relationship through the observation of phenomena in case studies. The model clarifies the process by which social groups interact with a lower-order effect and then generate a higher-order effect in an iterative manner. This study classifies social groups' responses into three forms-opposing, modifying, and advantage-taking action-and places them in six pathways. The model is expected to be used as an analytical tool for investigating and identifying impacts in the planning stage and as a framework for monitoring social groups' responses during the implementation stage of a policy, plan, program, or project (PPPPs).

Dose rate correction in medium dose rate brachytherapy for carcinoma cervix

International Nuclear Information System (INIS)

Patel, F.D.; Negi, P.S.; Sharma, S.C.; Kapoor, R.; Singh, D.P.; Ghoshal, S.

1998-01-01

Purpose: To establish the magnitude of brachytherapy dose reduction required for stage IIB and III carcinoma cervix patients treated by external radiation and medium dose rate (MDR) brachytherapy at a dose rate of 220±10 cGy/h at point A.Materials and methods: In study-I, at the time of MDR brachytherapy application at a dose rate of 220±10 cGy/h at point A, patients received either 3060 cGy, a 12.5% dose reduction (MDR-12.5), or 2450 cGy, a 30% dose reduction (MDR-30), to point A and they were compared to a group of previously treated LDR patients who received 3500 cGy to point A at a dose rate of 55-65 cGy/h. Study-II was a prospective randomized trial and patients received either 2450 cGy, a 30% dose reduction (MDR-II (30)) or 2800 cGy, a 20% dose reduction (MDR-II (20)), at point A. Patients were evaluated for local control of disease and morbidity. Results: In study-I the 5-year actuarial local control rate in the MDR-30 and MDR-12.5 groups was 71.7±10% and 70.5±10%, respectively, compared to 63.4±10% in the LDR group. However, the actuarial morbidity (all grades) in the MDR-12.5 group was 58.5±14% as against 34.9±9% in the LDR group (P 3 developed complication as against 62.5% of those receiving a rectal BED of (140 3 (χ 2 =46.43; P<0.001). Conclusion: We suggest that at a dose rate of 220±10 cGy/h at point A the brachytherapy dose reduction factor should be around 30%, as suggested by radiobiological data, to keep the morbidity as low as possible without compromising the local control rates. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Relation between dose of bendrofluazide, antihypertensive effect, and adverse biochemical effects

DEFF Research Database (Denmark)

Carlsen, J E; Køber, L; Torp-Pedersen, C

1990-01-01

OBJECTIVE--To determine the relevant dose of bendrofluazide for treating mild to moderate hypertension. DESIGN--Double blind parallel group trial of patients who were given placebo for six weeks and then randomly allocated to various doses of bendrofluazide (1.25, 2.5, 5, or 10 mg daily) or place...... of bendrofluazide to treat mild to moderate hypertension is 1.25-2.5 mg a day. Higher doses caused more pronounced adverse biochemical effects including adverse lipid effects. Previous trials with bendrofluazide have used too high doses....... relations between dose and effect were shown for potassium, urate, glucose, total cholesterol, and apolipoprotein B concentrations. The 1.25 mg dose increased only urate concentrations, whereas the 10 mg dose affected all the above biochemical variables. CONCLUSION--The relevant range of doses...

Efficacy and Safety of Daikenchuto for Constipation and Dose-Dependent Differences in Clinical Effects

Directory of Open Access Journals (Sweden)

Tatsuya Hirose

2018-01-01

Full Text Available Background. Daikenchuto (DKT is a Kampo medicine used for the treatment of constipation. In this study, we evaluated the effectiveness of DKT against constipation. Patients and Methods. Thirty-three patients administered DKT for constipation were selected and divided into low-dose (7.5 g DKT; n=22 and high-dose (15 g DKT; n=11 groups. We retrospectively evaluated weekly defaecation frequency, side effects, and clinical laboratory data. Results. Median defaecation frequencies after DKT administration (5, 5.5, 5, and 8 for the first, second, third, and fourth weeks, resp. were significantly higher than that before DKT administration (2 in all 33 cases (P<0.01. One case (3% of watery stool, one case of loose stools (3%, and no cases of abdominal pain (0% were observed. Median defaecation frequencies in the high-dose group (7 and 9 were significantly higher than those in the low-dose group (4 and 3 in the first (P=0.0133 and second (P=0.0101 weeks, respectively. There was no significant change in clinical laboratory values. Conclusion. We suggest that DKT increases defaecation frequency and is safe for treating constipation.

Lateral topography for reducing effective dose in low-dose chest CT.

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Bang, Dong-Ho; Lim, Daekeon; Hwang, Wi-Sub; Park, Seong-Hoon; Jeong, Ok-man; Kang, Kyung Wook; Kang, Hohyung

2013-06-01

The purposes of this study were to assess radiation exposure during low-dose chest CT by using lateral topography and to compare the lateral topographic findings with findings obtained with anteroposterior topography alone and anteroposterior and lateral topography combined. From November 2011 to February 2012, 210 male subjects were enrolled in the study. Age, weight, and height of the men were recorded. All subjects were placed into one of three subgroups based on the type of topographic image obtained: anteroposterior topography, lateral topography, and both anteroposterior and lateral topography. Imaging was performed with a 128-MDCT scanner. CT, except for topography, was the same for all subjects. A radiologist analyzed each image, recorded scan length, checked for any insufficiencies in the FOV, and calculated the effective radiation dose. One-way analysis of variance and multiple comparisons were used to compare the effective radiation exposure and scan length between groups. The mean scan length in the anteroposterior topography group was significantly greater than that of the lateral topography group and the combined anteroposterior and lateral topography group (p topography group (0.735 ± 0.033 mSv) was significantly lower than that for the anteroposterior topography group (0.763 ± 0.038 mSv) and the combined anteroposterior and lateral topography group (0.773 ± 0.038) (p < 0.001). Lateral topographic low-dose CT was associated with a lower effective radiation dose and scan length than either anteroposterior topographic low-dose chest CT or low-dose chest CT with both anteroposterior and lateral topograms.

Synergistic Effects of Ad-Libitum Low-Dose Fructose Drinking and Low-Dose Streptozotocin Treatment in Wistar Rats: A Mild Model of Type 2 Diabetes

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Asie Sadeghi

2017-07-01

Full Text Available To develop a convenient animal model of T2D by pretreatment with low-dose 10% w/v fructose (FRC solution followed by the injection of low doses of streptozotocin (STZ in Wistar rats. For this 8-week experimental study; rats were first fed a standard chow ad-libitum diet and either tap water (n=40 or 10% w/v FRC solution (n=40 for 4 weeks. Next, rats in each category were randomly allocated to 4 subgroups (n=10 each of low-dose STZ (25,35, and 45 mg/kg. The final mean fasting blood sugar (FBG of FRC+STZ45 (197±55.87 mg/dl were significantly higher than that of the STZ45 (P=0.015 and FRC (P=0.019 groups. FRC+STZ45 showed the highest insulin resistance demonstrated by insulin tolerance test [area under the curve (AUC of insulin tolerance test; P<0.05]. AUC was not significantly different between the STZ45 and non-STZ groups and between FRC and non-FRC fed groups. Furthermore, FBG levels did not differ between FRC and non-FRC groups. Body weight measurement showed that the FRC+STZ45 group had the lowest body weight compared to all other groups. Our data provide the evidence that FRC and STZ45 synergistically could induce hyperglycemia and insulin resistance in Wistar rats. Here we presented a feasible model for initial forms of T2D by employing pretreatment with low-dose FRC solution and treatment with low-dose STZ.

Exposure to low-dose barium by drinking water causes hearing loss in mice.

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Ohgami, Nobutaka; Hori, Sohjiro; Ohgami, Kyoko; Tamura, Haruka; Tsuzuki, Toyonori; Ohnuma, Shoko; Kato, Masashi

2012-10-01

We continuously ingest barium as a general element by drinking water and foods in our daily life. Exposure to high-dose barium (>100mg/kg/day) has been shown to cause physiological impairments. Direct administration of barium to inner ears by vascular perfusion has been shown to cause physiological impairments in inner ears. However, the toxic influence of oral exposure to low-dose barium on hearing levels has not been clarified in vivo. We analyzed the toxic influence of oral exposure to low-dose barium on hearing levels and inner ears in mice. We orally administered barium at low doses of 0.14 and 1.4 mg/kg/day to wild-type ICR mice by drinking water. The doses are equivalent to and 10-fold higher than the limit level (0.7 mg/l) of WHO health-based guidelines for drinking water, respectively. After 2-week exposure, hearing levels were measured by auditory brain stem responses and inner ears were morphologically analyzed. After 2-month exposure, tissue distribution of barium was measured by inductively coupled plasma mass spectrometry. Low-dose barium in drinking water caused severe hearing loss in mice. Inner ears including inner and outer hair cells, stria vascularis and spiral ganglion neurons showed severe degeneration. The Barium-administered group showed significantly higher levels of barium in inner ears than those in the control group, while barium levels in bone did not show a significant difference between the two groups. Barium levels in other tissues including the cerebrum, cerebellum, heart, liver and kidney were undetectably low in both groups. Our results demonstrate for the first time that low-dose barium administered by drinking water specifically distributes to inner ears resulting in severe ototoxicity with degeneration of inner ears in mice. Copyright © 2012 Elsevier Inc. All rights reserved.

Conditioned instrumental behaviour in the rat: Effects of prenatal irradiation with various low dose-rate doses

International Nuclear Information System (INIS)

Klug, H.

1986-01-01

4 groups of rats of the Wistar-strain were subjected to γ-irradiation on the 16th day of gestation. 5 rats received 0,6 Gy low dose rate irradiation, 5 animals received 0,9 Gy low dose and 6 high dose irradiation, 3 females were shamirradiated. The male offspring of these 3 irradiation groups and 1 control group were tested for locomotor coordination on parallel bars and in a water maze. The female offspring were used in an operant conditioning test. The locomotor test showed slight impairment of locomotor coordination in those animals irradiated with 0,9 Gy high dose rate. Swimming ability was significantly impaired by irradiation with 0,9 Gy high dose rate. Performance in the operant conditioning task was improved by irradiation with 0,9 Gy both low and high dose rate. The 0,9 Gy high dose rate group learned faster than all the other groups. For the dose of 0,9 Gy a significant dose rate effect could be observed. For the dose of 0,6 Gy a similar tendency was observed, differences between 0,6 Gy high and low dose rate and controls not being significant. (orig./MG) [de

Radiation doses to children during modified barium swallow studies

International Nuclear Information System (INIS)

Weir, Kelly A.; McMahon, Sandra M.; Long, Gillian; Bunch, Judith A.; Pandeya, Nirmala; Coakley, Kerry S.; Chang, Anne B.

2007-01-01

There are minimal data on radiation doses to infants and children undergoing a modified barium swallow (MBS) study. To document screening times, dose area product (DAP) and effective doses to children undergoing MBS and to determine factors associated with increased screening times and effective dose. Fluoroscopic data (screening time, DAP, kVp) for 90 consecutive MBS studies using pulse fluoroscopy were prospectively recorded; effective dose was calculated and data were analyzed for effects of behavior, number of swallow presentations, swallowing dysfunction and medical problems. Mean effective dose for the entire group was 0.0826 ± 0.0544 mSv, screening time 2.48 ± 0.81 min, and DAP 28.79 ± 41.72 cGy cm 2 . Significant differences were found across three age groups (≤1.0, >1.0-3.0 and >3.0 years) for effective dose (mean 0.1188, 0.0651 and 0.0529 mSv, respectively; P < 0.001), but not for screening time or DAP. Effective dose was correlated with screening time (P 0.007), DAP (P < 0.001), number of swallow presentations (P = 0.007), lower age (P = 0.017), female gender (P = 0.004), and height (P < 0.001). Screening time was correlated with total number of swallow presentations (P < 0.001) and DAP (P < 0.001). Screening times, DAP, effective dose, and child and procedural factors associated with higher effective doses are presented for children undergoing MBS studies. (orig.)

Phencyclidine retards autoshaping at a dose which does not suppress the required response.

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Coveney, J R; Sparber, S B

1982-06-01

Four groups of five food-deprived hooded Long-Evans rats were injected subcutaneously with saline (vehicle) or 2, 4 or 8 mg phencyclidine (PCP) hydrochloride/kg fifteen minutes before being placed for the first time into operant chambers modified to detect exploratory behaviors. Rearing was found to be more sensitive to disruption by phencyclidine than was unconditioned level touching (a measure of floor-level exploratory activities). In an autoshaping session immediately following, the group of animals given the low dose of PCP made as many lever-touch responses as the group given saline, but consumed fewer of the food pellets delivered. In addition, none of the animals in the low-dose group showed within-session shortening of the latency to respond which was observed in four of five control animals. The two other groups given higher doses of PCP demonstrated dose-related decrements in responding as well as a reduction in food pellet consumption during the first session of autoshaping. Over the next two daily autoshaping sessions, performance improved in those groups initially suppressed. Performance converged in all group by the third autoshaping session.

Chernobyl liquidators. The people and the doses

International Nuclear Information System (INIS)

Belyakov, Oleg V.; Steinhaeusler, Friedrich; Trott, Klaus-Ruediger

2000-01-01

This study is an attempt to evaluate the data available from the scientific literature concerning clean-up workers, or so-called liquidators, of the Chernobyl accident. There are several different definitions of liquidators: Legal definitions of 'liquidators'. Their importance rests on the fact that some state Chernobyl registers are based on these definitions. Definitions from various scientific reports. Definitions for the purpose, which have been published in scientific papers and books. The simplified definition of liquidators would be people who were directly involved in clean-up operations in the exclusion zone in 1986-1991. Estimations of the number of liquidators vary from 100 000 to 800 000 people. Four major cohorts of liquidators are now split among Russia (168,000 people), Belarus (63,500 people), Ukraine (123,536 people) and the Baltic States (about 15,000 people from Estonia, Latvia and Lithuania). The definition of liquidator and the formation of cohort are the most critical factor in liquidator-related studies and not enough attention is paid to this matter by researchers. The term 'liquidator' describes a very heterogeneous group of people. Liquidators may be grouped according to work performed in the exclusion zone or affiliation to various organisations. The majority of liquidators in 1986-1987 were conscripts and reservists of the Soviet Union Army. According to data from Russian National Medical and Dosimetric Registry, 76% of liquidators were 25-39 years old at the moment of arrival to the Chernobyl area. Only about 1% of liquidators was women. From the results of biodosimetry we know that the average accumulated dose estimation for the liquidator group is about 0.2 Gy. The official documented average dose from the Russian National Medical Dosimetric Registry is 0.13 Gy. However, the liquidator group contains some overexposed subgroups with a higher accumulated dose. Individual dosimetry is only available for small subgroups of liquidators

Chernobyl liquidators. The people and the doses

Energy Technology Data Exchange (ETDEWEB)

Belyakov, Oleg V. [Gray Laboratory Cancer Research Trust, Mount Vernon Hospital, Northwood (United Kingdom); Steinhaeusler, Friedrich [University of Salzburg, Institute of Physic and Biophysics, Salzburg (Austria); Trott, Klaus-Ruediger [Univ. of London, Queen Mary and Westfield College, St. Bartholomew' s and the Royal London Hospital School of Medicine and Dentistry, London (United Kingdom)

2000-05-01

This study is an attempt to evaluate the data available from the scientific literature concerning clean-up workers, or so-called liquidators, of the Chernobyl accident. There are several different definitions of liquidators: Legal definitions of 'liquidators'. Their importance rests on the fact that some state Chernobyl registers are based on these definitions. Definitions from various scientific reports. Definitions for the purpose, which have been published in scientific papers and books. The simplified definition of liquidators would be people who were directly involved in clean-up operations in the exclusion zone in 1986-1991. Estimations of the number of liquidators vary from 100 000 to 800 000 people. Four major cohorts of liquidators are now split among Russia (168,000 people), Belarus (63,500 people), Ukraine (123,536 people) and the Baltic States (about 15,000 people from Estonia, Latvia and Lithuania). The definition of liquidator and the formation of cohort are the most critical factor in liquidator-related studies and not enough attention is paid to this matter by researchers. The term 'liquidator' describes a very heterogeneous group of people. Liquidators may be grouped according to work performed in the exclusion zone or affiliation to various organisations. The majority of liquidators in 1986-1987 were conscripts and reservists of the Soviet Union Army. According to data from Russian National Medical and Dosimetric Registry, 76% of liquidators were 25-39 years old at the moment of arrival to the Chernobyl area. Only about 1% of liquidators was women. From the results of biodosimetry we know that the average accumulated dose estimation for the liquidator group is about 0.2 Gy. The official documented average dose from the Russian National Medical Dosimetric Registry is 0.13 Gy. However, the liquidator group contains some overexposed subgroups with a higher accumulated dose. Individual dosimetry is only available for small

Analysis of surface contributions to external doses in a radioactively contaminated urban environment designed by the EMRAS-2 Urban Areas Working Group

International Nuclear Information System (INIS)

Hwang, Won Tae; Jeong, Hae Sun; Jeong, Hyo Joon; Kim, Eun Han; Han, Moon Hee; Kim, In Gyu

2013-01-01

Highlights: ► External dose and contribution from radio-activated surface were evaluated for EMRAS-2 Urban Areas Working Group scenarios. ► The external doses showed a distinctive difference with the locations and precipitation. ► The contribution of contaminated surfaces for external dose depends on locations and precipitation. ► These results provide the essential information for decision-making support of countermeasures. - Abstract: The EMRAS-2 Urban Areas Working Group, which is supported by the IAEA, has designed a variety of accidental scenarios to test and improve the capabilities of the models used for an evaluation of radioactive contamination in an urban environment. A variety of models including a Korean model, METRO-K, are used for predictive results on the hypothetical scenarios. This paper describes the predictive results of METRO-K for the hypothetical scenarios designed in the Working Group. The external dose resulting from the air contamination of Co-60 was evaluated, and its contribution was analyzed with time as a function of the location of a receptor and precipitation conditions at the time of the contamination event. As a result, the external doses showed a distinctive difference with the locations to be evaluated and the precipitation conditions. Moreover, the contribution of contaminated surfaces for external doses was strongly dependent on the locations to be evaluated and the precipitation conditions. These results will provide essential information to assist the decision-making of appropriate countermeasures in an emergency situation of a radioactively contaminated urban environment

Doses of Chernobyl liquidators: Ukrainian prospective

International Nuclear Information System (INIS)

Chumak, Vadim V.; Bakhanova, Elena V.; Sholom, Sergey V.; Bouville, Andre; Luckyanov, Nickolas K.; Skaletsky, Yuri N.; Kryuchkov, Viktor P.

2008-01-01

least at group level. However, as anticipated, in about 10% of cases the dose records were artificially assigned. Analysis of such major discrepancies showed that the ratio of the number of overestimated doses to those that were underestimated is about 20:1. As a rule unrealistically high doses were assigned to some specific 'privileged' groups of military liquidators (i.e., commanders, logistics specialists, etc.). Such groups can, in principle, be isolated and excluded from analysis. Analysis of doses retrospectively reconstructed using the RADRUE technique shows that the second numerous category (∼28%) were civilians sent on mission to the 30-km zone (CSOM). These liquidators performed a broad variety of tasks at various times and places; as a result the dose distribution for this category is very broad. About 10% of Ukrainian liquidators took part in clean-up activities in April-May 1986 and generally received higher doses. Another 10% of liquidators belong to 'mixed' category, which is characterized by several work sessions (missions) that were defined by differing roles (tasks) during Chernobyl clean-up. Other categories, like victims of the accident, early respondents, and professional atomic workers contribute ≤1% of the total number of Ukrainian liquidators and their doses do not significantly affect the overall dose distribution. The data collected in the aforementioned studies allows reevaluation of dose distribution for Ukrainian liquidators. The new distribution is quite different from the previously circulated dose distribution derived from incomplete and biased ODRs stored in the SRU. (author)

Size-appropriate radiation doses in pediatric body CT: a study of regional community adoption in the United States

International Nuclear Information System (INIS)

Hopkins, Katharine L.; Vajtai, Petra L.; Pettersson, David R.; Spinning, Kristopher; Beckett, Brooke R.; Koudelka, Caroline W.; Bardo, Dianna M.E.

2013-01-01

During the last decade, there has been a movement in the United States toward utilizing size-appropriate radiation doses for pediatric body CT, with smaller doses given to smaller patients. This study assesses community adoption of size-appropriate pediatric CT techniques. Size-specific dose estimates (SSDE) in pediatric body scans are compared between community facilities and a university children's hospital that tailors CT protocols to patient size as advocated by Image Gently. We compared 164 pediatric body scans done at community facilities (group X) with 466 children's hospital scans. Children's hospital scans were divided into two groups: A, 250 performed with established pediatric weight-based protocols and filtered back projection; B, 216 performed with addition of iterative reconstruction technique and a 60% reduction in volume CT dose index (CTDI vol ). SSDE was calculated and differences among groups were compared by regression analysis. Mean SSDE was 1.6 and 3.9 times higher in group X than in groups A and B and 2.5 times higher for group A than group B. A model adjusting for confounders confirmed significant differences between group pairs. Regional community hospitals and imaging centers have not universally adopted child-sized pediatric CT practices. More education and accountability may be necessary to achieve widespread implementation. Since even lower radiation doses are possible with iterative reconstruction technique than with filtered back projection alone, further exploration of the former is encouraged. (orig.)

Size-appropriate radiation doses in pediatric body CT: a study of regional community adoption in the United States

Energy Technology Data Exchange (ETDEWEB)

Hopkins, Katharine L.; Vajtai, Petra L. [Oregon Health and Science University, Department of Diagnostic Radiology, DC7R, Portland, OR (United States); Oregon Health and Science University, Department of Pediatrics, Portland, OR (United States); Pettersson, David R.; Spinning, Kristopher; Beckett, Brooke R. [Oregon Health and Science University, Department of Diagnostic Radiology, DC7R, Portland, OR (United States); Koudelka, Caroline W. [Oregon Health and Science University, Division of Biostatistics, Department of Public Health and Preventive Medicine, Portland, OR (United States); Bardo, Dianna M.E. [Oregon Health and Science University, Department of Diagnostic Radiology, DC7R, Portland, OR (United States); Oregon Health and Science University, Department of Cardiovascular Medicine, Portland, OR (United States)

2013-09-15

During the last decade, there has been a movement in the United States toward utilizing size-appropriate radiation doses for pediatric body CT, with smaller doses given to smaller patients. This study assesses community adoption of size-appropriate pediatric CT techniques. Size-specific dose estimates (SSDE) in pediatric body scans are compared between community facilities and a university children's hospital that tailors CT protocols to patient size as advocated by Image Gently. We compared 164 pediatric body scans done at community facilities (group X) with 466 children's hospital scans. Children's hospital scans were divided into two groups: A, 250 performed with established pediatric weight-based protocols and filtered back projection; B, 216 performed with addition of iterative reconstruction technique and a 60% reduction in volume CT dose index (CTDI{sub vol}). SSDE was calculated and differences among groups were compared by regression analysis. Mean SSDE was 1.6 and 3.9 times higher in group X than in groups A and B and 2.5 times higher for group A than group B. A model adjusting for confounders confirmed significant differences between group pairs. Regional community hospitals and imaging centers have not universally adopted child-sized pediatric CT practices. More education and accountability may be necessary to achieve widespread implementation. Since even lower radiation doses are possible with iterative reconstruction technique than with filtered back projection alone, further exploration of the former is encouraged. (orig.)

Patient dose in digital mammography

International Nuclear Information System (INIS)

Chevalier, Margarita; Moran, Pilar; Ten, Jose I.; Fernandez Soto, Jose M.; Cepeda, T.; Vano, Eliseo

2004-01-01

examination was 3.8 mGy, with 4 images per examination on average. The mean dose for cranio-caudal view (CC) images was 1.8 mGy, which is lower than that for medio-lateral oblique (MLO) view because the thickness for CC images was on average 10% lower than that for MLO images. Mean AGD T for the oldest group of women (1.90) was 3% higher than the AGD T for the younger group (1.85) due to the larger compressed breast thickness of women in the older group (10% on average). Differences between the corresponding AGD T values of each age group were lowest for breast thicknesses in the range 40-60 mm, being slightly higher for the women in the older group

Study of single dose toxic test of Sweet Bee Venom in Beagle Dogs

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Hye-Chul, Yoon

2010-12-01

Full Text Available Objectives : This study was performed to analyse single dose toxicity of Sweet Bee Venom(Sweet BV extracted from the bee venom in Beagle dogs. Methods : All experiments were conducted under the regulations of Good Laboratory Practice (GLP at Biotoxtech Company, a non-clinical study authorized institution. Male and female Beagle dogs of 5-6 months old were chosen for the pilot study of single dose toxicity of Sweet BV which was administered at the level of 9.0 ㎎/㎏ body weight which is 1300 times higher than the clinical application dosage as the high dosage, followed by 3.0 and 1.0 ㎎/㎏ as midium and low dosage, respectively. Equal amount of excipient(normal saline to the Sweet BV experiment groups was administered as the control group. Results : 1. No mortality was witnessed in all of the experiment groups. 2. Hyperemia and movement disorder were observed around the area of administration in all the experiment groups, and higher occurrence in the higher dosage treatment. 3. For weight measurement, Neither male nor female groups showed significant changes. 4. To verify abnormalities of organs and tissues, thigh muscle which treated with Sweet BV, brain, liver, lung, kidney, and spinal cords were removed and histologocal observation using H-E staining was conducted. In the histologocal observation of thigh muscle, cell infiltration, inflammation, degeneration, necrosis of muscle fiber, and fibrosis were found in both thigh tissue. And the changes depend on the dose of Sweet BV. But the other organs did not showed in any abnormality. 5. The maximum dose of Sweet BV in Beagle dogs were over 9 ㎎/㎏ in this study. Conclusions : The above findings of this study suggest that Sweet BV is a relatively safe treatment medium. Further studies on the toxicity of Sweet BV should be conducted to yield more concrete evidences.

Population doses from terrestrial gamma exposure in China

International Nuclear Information System (INIS)

Ren, T.; Wang, Z.; Zhu, C.

1992-01-01

In order to estimate terrestrial gamma radiation exposure three nationwide surveys have been completed since 1981. The population-weighted outdoor and indoor arithmetic means of gamma dose rate based on momentary dose rate measurements using a NaI(Tl) environmental radiation meter and high-pressure ionisation chamber are, respectively, 80.3 nGy.h -1 and 120 nGy.h -1 . Based on integrating dose measurement using TLD CaSO 4 /Dy they are 67 nGy.h -1 and 89 nGy.h -1 respectively, and based on natural radionuclides concentrations in soil, determined by gamma spectroscopy analyses, they are 72.8 nGy.h -1 and 102 nGy.h -1 , respectively. These surveys were conducted independently by different groups. The best estimations of population-weighted gamma dose rates in China, based on all these surveys, would be 70 nGy.h -1 and 98 nGy.h -1 for outdoors and indoors, respectively. The annual average of effective dose equivalent is 0.56 mSv. These values are higher than the world averages estimated by UNSCEAR. The main reason is that the concentrations of 232 Th and 40 K in the soil of China are much higher than the world average estimated. (author)

Safety of high-dose daptomycin in patients with severe renal impairment

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Tai CH

2018-03-01

Full Text Available Chih-Hsun Tai,1 Chi-Hao Shao,2 Chen-You Chen,2 Shu-Wen Lin,1–3 Chien-Chih Wu1,2 1Department of Pharmacy, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan; 2School of Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan; 3Graduate Institute of Clinical Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan Background: Treatment options are limited for infections due to multidrug-resistant Gram-positive pathogens. Daptomycin is a lipopeptide antibiotic with concentration-dependent killing characteristic and dose-dependent post-antibiotic effect. To achieve optimized pharmacodynamic effect, some experts advocated using a high dose of daptomycin (≥9 mg/kg for severe infections. However, the safety of high-dose therapy in patients with renal impairment remains unknown. This study was aimed to evaluate the safety of daptomycin in patients with severe renal impairment. Methods: This was a retrospective study performed by reviewing electronic medical records. Patients with severe renal impairment who were treated with daptomycin in a tertiary teaching hospital between January 1, 2013, and June 30, 2016, were included for evaluation. The incidence rates of creatine kinase (CK elevation between high-dose (≥9 mg/kg and standard-dose (<9 mg/kg groups were compared. Results: Overall, 164 patients met the inclusion criteria, and 114 (69.5% of them were on renal replacement therapy. Vancomycin-resistant enterococci were the most common pathogens (61.3% of the patients with documented pathogens. The treatment success rate was 51.6% in the 91 patients with bacteremia. The average dose of daptomycin was 8.0±2.3 mg/kg, and 37 (22.6% patients received ≥9 mg/kg. CK levels were followed in 108 (65.9% patients. Significantly higher incidence of CK elevation was found in the high-dose group compared with that in the standard-dose group (10.8% vs 1.6%, P<0.05. Moreover

Effect of Low Dose gamma-ray Irradiation on the Germination and Growth in Red Pepper (Capcicum annuum L.)

International Nuclear Information System (INIS)

Lee Eun-Kyung; Kim Jae-Sung

1998-01-01

This study was conducted to determine the effect of low dose gamma-ray irradiation in red pepper. The germination percentage, plant, the number of flower, chlorophyll contents, leaf length and width were observed from plants grown with red pepper seeds irradiated with various low dose of gamma-ray. The germination percentage of irradiation group treatmented gamma-ray was much higher than that of the control. Specially the germination percentage after sowing red pepper seeds on paper towel was higher than 1,000 and 2,000 rad irradiation group. The height of plants grown with red pepper seeds irradiated with gamma-ray was increased in 100, 200 and 400 rad irradiation group compared to that of the control. The height of plant from 2,400 rad irradiation group, however, was shorter than that of the control. Nutrient contents of leaves of plants grown with red pepper seeds irradiated with various dose of gamma-ray were significantly increased in 800 and 1,200 rad irradiation group. Electric conductivity (EC) of the water used for seed germination was lower irradiation group than control group. Therefore, there was the possibility to increase the germination and plant growth with gamma-ray of adequate low dose

Study on children patient dose in single-detector and multi-detector row helical computed tomography

International Nuclear Information System (INIS)

Lu Heqing; Zhu Guoying; Zhuo Weihai; Liu Haikuan; Guo Changyi

2008-01-01

Objective: To study and evaluate the radiation dose of children patient in single-detector and multi-detector row helical CT scan. Methods: The head and body CT dose index of 21 CT scanners were tested. Then the values of CTDI w , CTDI vol and DLP were calculated combining with the parameters of routine head and chest scan for children of 0-1 year old group, 5 years old group, 10 years old group and adults. The effective doses of children of every age group and adults in routine head and chest scan were subsequently estimated from effective dose per DLP by age and the calculated values of DLP. Results: CTDI per mAs is greater in the head than that in the body. In head routine scan, the effective doses of 0-1 year old group,5 years old group and 10 year old group were 2.2, 1.3 and 1.1 mSv, respectively. In chest routine scan, the effective doses of 0-1 year old group,5 years old group and 10 years old group were 5.3, 3.1 and 3.4 mSv, respectively. Effective doses to children per mAs are equally 1.8 times higher than corresponding values for adults. The CTDI vol , DLP and effective dose to children in head routine scan for MDCT were greater those that for single-detector CT and dual- detector CT. The CTDI vol , DLP and effective dose to children in chest routine scan for MDCT and dual-detector row CT were smaller than that for single-detector row CT. Conclusions: Children me more radiation risk in CT examination as compared with adults. So we should strictly abide by justification of children CT examination, and optimize the parameters of CT scan rationally in order to reduce the radiation dose to children patient as much as possible. (authors)

Analysis of complications in a prospective randomized trial comparing two brachytherapy low dose rates in cervical carcinoma

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-07-30

The analysis of complications in a prospective randomized trial comparing two preoperative brachytherapy low-dose rates in early stage cervical cancer is presented. The objective of this trial was to determine the benefits, if any, of the higher-dose rate within the therapeutic aresenal for this patient population, in terms of survival, local control, and complications. Overall survival, 85% at 2 years and local control, 93% at 2 years, were similarly distributed between the two groups. Regardless of their nature and severity, 139 and 175 complications were observed among 63% and 75% of patients, in the 0.4 and 0.8 Gy/h dose rate groups respectively. Gynecologic and urinary complications were the most frequent (38% and 28% of all complications), followed by vascular (15%), digestive (10%), nervous (5%), and cutaneous (5%). A total of 14 and 17 severe complications (Grade 3) were observed in 7% and 13% of patients, respectively in the 0.4 and 0.8 Gy/h dose rate groups (p = 0.12) Nonparametric survival methods used to compare the time to the first complication did not show a significant difference between the two groups: 62% and 72% at 2 years (p = 0.27). When the first complication and its evolution were considered (early complications), the prevalence of complications was not significantly different between the two groups: 28% vs. 34% at 2 years (p = 0.31). In this prospective trial, patients were regularly followed-up and complications of varying nature and severity were observed in succession during follow-up. When successive complications and their evolution were taken into account, the prevalence of complications was significantly greater in the higher-dose rate group: 30% vs 45% at 2 years (p = 0.03). The results of this trial showed that long-term effects of treatment, when represented by prevalence of complications over time, were more frequent in the higher dose rate group. 33 refs., 3 figs., 5 tabs.

Estimation of patient dose in abdominal CT examination in some Sudanese hospitals

International Nuclear Information System (INIS)

Adam, Ebthal Adam Shikhalden

2016-04-01

The use of CT in medical diagnosis delivers radiation doses to patients that are higher than those from other radiological procedures. The aim of this study was to estimate radiation doses in abdomen CT examinations of patients in two Sudanese hospitals. Details were obtained from approximately 80 CT examinations and included all age groups ( adults and pediatric). The results from the two hospitals were compared with each other as well as with the IAEA guidance level for this particular investigation. The estimation of radiation doses were carried out by calculating volume dose index (CTD1vol), dose length product (DLP), doses to some organs of interest and effective dose (E) using the software program "CT EXPO V2.1". The study showed that the mean DLP of the one hospitals ASH is 1736.7 mGy.cm which is by far much higher than that for the other hospital NMDC which stands at 185.3 mGy.cm, as well as higher than the IAEA level which is 696 mGy.cm. The study showed that the mean CTD1vol for patients in ASH is 36.2 mGy which again higher than that for the other hospital which is 3.9 mGy and higher than the IAEA level which is 10.9 mGy calculating the effective dose for patients in the two hospitals reveals that the mean effective dose of patient in one hospital (ASH) is 26.25 mSv, which is quite high compared with other hospital (NMDC), which has the mean value of 2.8 mGv and also higher than the IAEA level from this investigation which is 7.6 mSv. Regarding organ doses, the study showed that organ doses in hospital ASH are always higher than that calculated in hospital NMDC and the highest doses in both hospital were delivered to the kidneys with mean values of 50.24 mGy and 5045 mGy for the two hospitals respectively. The study showed that there is an urgent need for optimizing patient doses in such CT examinations. This can be ensured by providing training and retraining for workers and conducting quality control measurements and preventive maintenance regularly so

Knowledge-based iterative model reconstruction technique in computed tomography of lumbar spine lowers radiation dose and improves tissue differentiation for patients with lower back pain

International Nuclear Information System (INIS)

Yang, Cheng Hui; Wu, Tung-Hsin; Lin, Chung-Jung; Chiou, Yi-You; Chen, Ying-Chou; Sheu, Ming-Huei; Guo, Wan-Yuo; Chiu, Chen Fen

2016-01-01

Highlights: • Knowledge-based IMR improves tissue differentiation in CT of L-spine better than hybrid IR (iDose 4 ). • Higher strength IMR improves image qualities of the IVD and IVF in spinal stenosis. • IMR provides diagnostic lower dose CT of L-spine. - Abstract: Purpose: To evaluate the image quality and diagnostic confidence of reduced-dose computed tomography (CT) of the lumbar spine (L-spine) reconstructed with knowledge-based iterative model reconstruction (IMR). Materials and methods: Prospectively, group A consisted of 55 patients imaged with standard acquisition reconstructed with filtered back-projection. Group B consisted of 58 patients imaged with half tube current, reconstructed with hybrid iterative reconstruction (iDose 4 ) in Group B1 and knowledge-based IMR in Group B2. Signal-to-noise ratio (SNR) of different regions, the contrast-to-noise ratio between the intervetebral disc (IVD) and dural sac (D-D CNR), and subjective image quality of different regions were compared. Higher strength IMR was also compared in spinal stenosis cases. Results: The SNR of the psoas muscle and D-D CNR were significantly higher in the IMR group. Except for the facet joint, subjective image quality of other regions including IVD, intervertebral foramen (IVF), dural sac, peridural fat, ligmentum flavum, and overall diagnostic acceptability were best for the IMR group. Diagnostic confidence of narrowing IVF and IVD was good (kappa = 0.58–0.85). Higher strength IMR delineated IVD better in spinal stenosis cases. Conclusion: Lower dose CT of L-spine reconstructed with IMR demonstrates better tissue differentiation than iDose 4 and standard dose CT with FBP.

Knowledge-based iterative model reconstruction technique in computed tomography of lumbar spine lowers radiation dose and improves tissue differentiation for patients with lower back pain

Energy Technology Data Exchange (ETDEWEB)

Yang, Cheng Hui [Department of Medical Imaging, Pojen General Hopsital, Taipei, Taiwan (China); School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Wu, Tung-Hsin [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan (China); Lin, Chung-Jung, E-mail: bcjlin@me.com [School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan (China); Chiou, Yi-You; Chen, Ying-Chou; Sheu, Ming-Huei; Guo, Wan-Yuo; Chiu, Chen Fen [School of Medicine, National Yang-Ming University, Taipei, Taiwan (China); Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan (China)

2016-10-15

Highlights: • Knowledge-based IMR improves tissue differentiation in CT of L-spine better than hybrid IR (iDose{sup 4}). • Higher strength IMR improves image qualities of the IVD and IVF in spinal stenosis. • IMR provides diagnostic lower dose CT of L-spine. - Abstract: Purpose: To evaluate the image quality and diagnostic confidence of reduced-dose computed tomography (CT) of the lumbar spine (L-spine) reconstructed with knowledge-based iterative model reconstruction (IMR). Materials and methods: Prospectively, group A consisted of 55 patients imaged with standard acquisition reconstructed with filtered back-projection. Group B consisted of 58 patients imaged with half tube current, reconstructed with hybrid iterative reconstruction (iDose{sup 4}) in Group B1 and knowledge-based IMR in Group B2. Signal-to-noise ratio (SNR) of different regions, the contrast-to-noise ratio between the intervetebral disc (IVD) and dural sac (D-D CNR), and subjective image quality of different regions were compared. Higher strength IMR was also compared in spinal stenosis cases. Results: The SNR of the psoas muscle and D-D CNR were significantly higher in the IMR group. Except for the facet joint, subjective image quality of other regions including IVD, intervertebral foramen (IVF), dural sac, peridural fat, ligmentum flavum, and overall diagnostic acceptability were best for the IMR group. Diagnostic confidence of narrowing IVF and IVD was good (kappa = 0.58–0.85). Higher strength IMR delineated IVD better in spinal stenosis cases. Conclusion: Lower dose CT of L-spine reconstructed with IMR demonstrates better tissue differentiation than iDose{sup 4} and standard dose CT with FBP.

Radiation dose to the lens and cataract formation

International Nuclear Information System (INIS)

Henk, J.M.; Whitelocke, R.A.F.; Warrington, A.P.; Bessell, E.M.

1993-01-01

The purpose of this work was to determine the radiation tolerance of the lens of the eye and the incidence of radiation-induced lens changes in patients treated by fractionated supervoltage radiation therapy for orbital tumors. Forty patients treated for orbital lymphoma and pseudotumor with tumor doses of 20--40 Gy were studied. The lens was partly shielded using lead cylinders in most cases. The dose to the germinative zone of the lens was estimated by measurements in a tissue equivalent phantom using both film densitometry and thermoluminescent dosimetry. Opthalmological examination was performed at 6 monthly intervals after treatment. The lead shield was found to reduce the dose to the germinative zone of the lens to between 36--50% of the tumor dose for Cobalt beam therapy, and to between 11--18% for 5 MeV x-rays. Consequently, the lens doses were in the range 4.5--30 Gy in 10--20 fractions. Lens opacities first appeared from between 3 and 9 years after irradiation. Impairment of visual acuity ensued in 74% of the patients who developed lens opacities. The incidence of lens changes was strongly dose-related. None was seen after doses of 5 Gy or lower, whereas doses of 16.5 Gy or higher were all followed by lens opacities which impaired visual acuity. The largest number of patients received a maximum lens dose of 15 Gy; in this group the actuarial incidence of lens opacities at 8 years was 57% with visual impairment in 38%. The adult lens can tolerate a total dose of 5 Gy during a fractionated course of supervoltage radiation therapy without showing any changes. Doses of 16.5 Gy or higher will almost invariably lead to visual impairment. The dose which causes a 50% probability of visual impairment is approximately 15 Gy. 10 refs., 4 figs., 1 tab

Serum tocopherol levels in very preterm infants after a single dose of vitamin E at birth.

Science.gov (United States)

Bell, Edward F; Hansen, Nellie I; Brion, Luc P; Ehrenkranz, Richard A; Kennedy, Kathleen A; Walsh, Michele C; Shankaran, Seetha; Acarregui, Michael J; Johnson, Karen J; Hale, Ellen C; Messina, Lynn A; Crawford, Margaret M; Laptook, Abbot R; Goldberg, Ronald N; Van Meurs, Krisa P; Carlo, Waldemar A; Poindexter, Brenda B; Faix, Roger G; Carlton, David P; Watterberg, Kristi L; Ellsbury, Dan L; Das, Abhik; Higgins, Rosemary D

2013-12-01

Our aim was to examine the impact of a single enteral dose of vitamin E on serum tocopherol levels. The study was undertaken to see whether a single dose of vitamin E soon after birth can rapidly increase the low α-tocopherol levels seen in very preterm infants. If so, this intervention could be tested as a means of reducing the risk of intracranial hemorrhage. Ninety-three infants vitamin E or placebo by gastric tube within 4 hours of birth. The vitamin E group received 50 IU/kg of vitamin E as dl-α-tocopheryl acetate (Aquasol E). The placebo group received sterile water. Blood samples were taken for measurement of serum tocopherol levels by high-performance liquid chromatography before dosing and 24 hours and 7 days after dosing. Eighty-eight infants received the study drug and were included in the analyses. The α-tocopherol levels were similar between the groups at baseline but higher in the vitamin E group at 24 hours (median 0.63 mg/dL vs. 0.42 mg/dL, P = .003) and 7 days (2.21 mg/dL vs 1.86 mg/dL, P = .04). There were no differences between groups in γ-tocopherol levels. At 24 hours, 30% of vitamin E infants and 62% of placebo infants had α-tocopherol levels vitamin E raised serum α-tocopherol levels, but to consistently achieve α-tocopherol levels >0.5 mg/dL, a higher dose or several doses of vitamin E may be needed.

Conflict Management in Student Groups - a Teacher’s Perspective in Higher Education

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Markus Borg

2011-12-01

Full Text Available Students working in groups is a commonly used method of instruction in higher education, popularized by the introduction of problem based learning. As a result, management of small groups of people has become an important skill for teachers. The objective of our study is to investigate why conflicts arise in student groups at the Faculty of Engineering at Lund University and how teachers manage them. We have conducted an exploratory interdepartmental interview study on teachers' views on this matter, interviewing ten university teachers with different levels of seniority. Our results show that conflicts frequently arise in group work, most commonly caused by different levels of ambition among students. We also found that teachers prefer to work proactively against conflicts and stress the student’s responsibility. Finally, we show that teachers at our faculty tend to avoid the more drastic conflict resolution strategies suggested by previous research. The outcome of our study could be used as input to future guidelines on conflict management in student groups.

Dose estimation using different ways of irradiation in a group of infants from zones affected by the Chernobyl accident

International Nuclear Information System (INIS)

Cruz Suarez, R.; Jova Sed, L.; Corripio, J.A.

1993-01-01

A dosimetry study is done to 4506 children from the Republic of Ukraine (69,3%), Belarus (8,1%) and Russian (22,5%) from 659 village and with ages between 1 and 17 years old. The study covers several stages. We can mention, for example, the dose estimation of iodine 121 in thyroids, the dose estimation for contamination with strontium 90 in the field and the calculation of the effective dose integrated in 70 years for the incorporation of cesium 137 in the body of the children, assuming a model of chronic incorporation. The estimation of the effective dose due to the strontium 90 was limited to a small group of 1314 children of those zones where the values of surface contamination of the field with this radionuclide are know

Biosphere model for assessing doses from nuclear waste disposal

International Nuclear Information System (INIS)

Zach, R.; Amiro, B.D.; Davis, P.A.; Sheppard, S.C.; Szekeley, J.G.

1994-01-01

The biosphere model, BIOTRAC, for predicting long term nuclide concentrations and radiological doses from Canada's nuclear fuel waste disposal concept of a vault deep in plutonic rock of the Canadian Shield is presented. This generic, boreal zone biosphere model is based on scenario analysis and systems variability analysis using Monte Carlo simulation techniques. Conservatism is used to bridge uncertainties, even though this creates a small amount of extra nuclide mass. Environmental change over the very long assessment period is mainly handled through distributed parameter values. The dose receptors are a critical group of humans and four generic non-human target organisms. BIOTRAC includes six integrated submodels and it interfaces smoothly with a geosphere model. This interface includes a bedrock well. The geosphere model defines the discharge zones of deep groundwater where nuclides released from the vault enter the biosphere occupied by the dose receptors. The size of one of these zones is reduced when water is withdrawn from the bedrock well. Sensitivity analysis indicates 129 I is by far the most important radionuclide. Results also show bedrock-well water leads to higher doses to man than lake water, but the former doses decrease with the size of the critical group. Under comparable circumstances, doses to the non-human biota are greater than those for man

Gonad doses for male patients from stomach examination and oral cholegraphy using the X-ray image intensifying technique and television fluoroscopy

International Nuclear Information System (INIS)

Steinbach, W.; Richter, K.; Koenig, W.; Menzel, B.; Reisinger, W.; Uhlich, F.

1979-01-01

The gonad dose was measured for male patients undergoing stomach examinations and oral cholegraphy by means of a diagnostic twelve pulse generator (TuR D 1500) and an X-ray apparatus 'Diagnost 100' (Philips-Mueller). In a small group of patients the gonad dose was ascertained per exposure to a 70 mm single spot film, to a 24 cm x 30 cm full size radiograph, and per minute of exposure to image intensifier fluoroscopy. The total gonad dose in both the diagnostic techniques was determined seperately in larger groups of patients. In stomach examination large size radiography led to a gonad dose 20 times higher than that obtained with the spot film technique, while exposure from cholegraphy was 10 times higher. The gonad dose per exposure of a single spot film was about 0.5 mrad. In examinations of the stomach the gonad dose from one minute fluroscopy was 18 times higher than the doses determined for a single spot film, and in cholegraphy it was 10 times higher. Supposing mean values of the number of radiographs and of the fluoroscopy time according to the conditions applied, the gonad dose in stomach examination from the film-screen technique is about twice that from the television image-intensifying technique. By comparison, oral cholegraphy exclusively performed by large-size radiography yielded about the same gonad dose as the spot film television technique. Total dose values determined separately confirmed these evaluations. (author)

Dose-dependent effect of ghrelin on gastric emptying in rats and the related mechanism of action

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Shu-Guang Cao

2016-03-01

Full Text Available The aim of this study was to investigate the dose-dependent effect of ghrelin on gastric emptying in rats and the related mechanism of action. Sixty Wistar rats were randomized into control and test groups, which respectively received intraperitoneal injection of normal saline and ghrelin at different doses (0.5 nmol/kg, 1.0 nmol/kg, 1.5 nmol/kg, 2.0 nmol/kg, and 2.5 nmol/kg. After 45 minutes, all rats were gavaged with semisolid paste. The gastric emptying rate was determined 30 minutes later, and the plasma cholecystokinin level was tested by radioimmunoassay. The mean gastric emptying rate in the test groups was significantly higher than in the control group (38.24 ± 7.15% and 27.18 ± 2.37%, respectively, p < 0.05. Medium and high doses of ghrelin (1.0 nmol/kg, 1.5 nmol/kg, 2.0 nmol/kg, and 2.5 nmol/kg, but not low dose (0.5 nmol/kg, accelerated the gastric emptying. In addition, the plasma cholecystokinin level in the test groups was significantly higher than in the control group (p < 0.01. The gastric emptying rate was positively correlated with the plasma cholecystokinin level (p < 0.01. Intraperitoneal injection of ghrelin at medium and high doses significantly accelerated gastric emptying in rats.

Model-Based Evaluation of Higher Doses of Rifampin Using a Semimechanistic Model Incorporating Autoinduction and Saturation of Hepatic Extraction.

Science.gov (United States)

Chirehwa, Maxwell T; Rustomjee, Roxana; Mthiyane, Thuli; Onyebujoh, Philip; Smith, Peter; McIlleron, Helen; Denti, Paolo

2016-01-01

Rifampin is a key sterilizing drug in the treatment of tuberculosis (TB). It induces its own metabolism, but neither the onset nor the extent of autoinduction has been adequately described. Currently, the World Health Organization recommends a rifampin dose of 8 to 12 mg/kg of body weight, which is believed to be suboptimal, and higher doses may potentially improve treatment outcomes. However, a nonlinear increase in exposure may be observed because of saturation of hepatic extraction and hence this should be taken into consideration when a dose increase is implemented. Intensive pharmacokinetic (PK) data from 61 HIV-TB-coinfected patients in South Africa were collected at four visits, on days 1, 8, 15, and 29, after initiation of treatment. Data were analyzed by population nonlinear mixed-effects modeling. Rifampin PKs were best described by using a transit compartment absorption and a well-stirred liver model with saturation of hepatic extraction, including a first-pass effect. Autoinduction was characterized by using an exponential-maturation model: hepatic clearance almost doubled from the baseline to steady state, with a half-life of around 4.5 days. The model predicts that increases in the dose of rifampin result in more-than-linear drug exposure increases as measured by the 24-h area under the concentration-time curve. Simulations with doses of up to 35 mg/kg produced results closely in line with those of clinical trials. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Age- and gender-specific estimates of cumulative CT dose over 5 years using real radiation dose tracking data in children

International Nuclear Information System (INIS)

Lee, Eunsol; Goo, Hyun Woo; Lee, Jae-Yeong

2015-01-01

It is necessary to develop a mechanism to estimate and analyze cumulative radiation risks from multiple CT exams in various clinical scenarios in children. To identify major contributors to high cumulative CT dose estimates using actual dose-length product values collected for 5 years in children. Between August 2006 and July 2011 we reviewed 26,937 CT exams in 13,803 children. Among them, we included 931 children (median age 3.5 years, age range 0 days-15 years; M:F = 533:398) who had 5,339 CT exams. Each child underwent at least three CT scans and had accessible radiation dose reports. Dose-length product values were automatically extracted from DICOM files and we used recently updated conversion factors for age, gender, anatomical region and tube voltage to estimate CT radiation dose. We tracked the calculated CT dose estimates to obtain a 5-year cumulative value for each child. The study population was divided into three groups according to the cumulative CT dose estimates: high, ≥30 mSv; moderate, 10-30 mSv; and low, <10 mSv. We reviewed clinical data and CT protocols to identify major contributors to high and moderate cumulative CT dose estimates. Median cumulative CT dose estimate was 5.4 mSv (range 0.5-71.1 mSv), and median number of CT scans was 4 (range 3-36). High cumulative CT dose estimates were most common in children with malignant tumors (57.9%, 11/19). High frequency of CT scans was attributed to high cumulative CT dose estimates in children with ventriculoperitoneal shunt (35 in 1 child) and malignant tumors (range 18-49). Moreover, high-dose CT protocols, such as multiphase abdomen CT (median 4.7 mSv) contributed to high cumulative CT dose estimates even in children with a low number of CT scans. Disease group, number of CT scans, and high-dose CT protocols are major contributors to higher cumulative CT dose estimates in children. (orig.)

Improvement of heart function in postinfarct heart failure swine models after hepatocyte growth factor gene transfer: comparison of low-, medium- and high-dose groups.

Science.gov (United States)

Yang, Zhi-jian; Chen, Bo; Sheng, Zhang; Zhang, Ding-guo; Jia, En-zhi; Wang, Wei; Ma, Dong-chao; Zhu, Tie-bing; Wang, Lian-sheng; Li, Chun-jian; Wang, Hui; Cao, Ke-jiang; Ma, Wen-zhu

2010-04-01

Despite advances in surgical and reperfusion therapy, there is no effective therapy currently exists to prevent the progressive decline in cardiac function following myocardial infarction. Hepatocyte growth factor has potent angiogenic and anti-apoptotic activities. The aim of this study was to investigate the therapeutic effect and dose-effect relationship on postinfarction heart failure with different doses of adenovirus-mediated human hepatocyte growth factor (Ad(5)-HGF) transference in swine models. Totally twenty swine were randomly divided into four groups: (a) control group (null- Ad(5), 1 ml); (b) low-dose group (1 x 10(9) Pfu/ml Ad(5)-HGF, 1 ml); (c) medium-dose group (5 x 10(9) Pfu/ml Ad(5)-HGF, 1 ml); (d) high-dose group (1 x 10(10) Pfu/ml Ad(5)-HGF, 1 ml). Four weeks after left anterior descending coronary artery (LAD) ligation, different doses of Ad(5)-HGF were transferred in three therapeutic groups via right coronary artery. Four and seven weeks after LAD ligation, gate cardiac perfusion imaging was performed to evaluate cardiac perfusion and left ventricular ejection fraction (LVEF). Seven weeks after surgery, the apoptotic index of cardiocyte was observed by TUNEL, the expression of Bcl-2, Bax, alpha-SMA and Factor VIII in the border zones were evaluated by immunohistochemistry, respectively. Four weeks after myocardial infarction, no significant difference was observed among four groups. Three weeks after Ad(5)-HGF transfer, the improvement of cardiac perfusion and LVEF was obviously observed, especially after 1 x 10(10) Pfu Ad(5)-HGF transfer. TUNEL assay showed that 5 x 10(9) Pfu and 1 x 10(10) Pfu Ad(5)-HGF treatment had a obvious reduction in the apoptotic index compared with the null-Ad(5) group, especially after 1 x 10(10) Pfu Ad(5)-HGF treatment. The expression of Bcl-2 protein was increased and the expression of Bax protein was inhibited in the 5 x 10(9) Pfu and 1 x 10(10) Pfu Ad(5)-HGF groups compared with the null-Ad(5) group. The vessel

A prospective randomized study of the efficacy and cost-effectiveness of high and low dose regimens of I-131 treatment in hyperthyroidism.

Science.gov (United States)

Pusuwan, Pawana; Tuntawiroon, Malulee; Sritongkul, Nopamol; Chaudakshetrin, Pachee; Nopmaneejumruslers, Cherdchai; Komoltri, Chulalak; Thepamongkhol, Kullathorn; Khiewvan, Benjapa; Tuchinda, Pongpija; Sriussadaporn, Sutin

2011-03-01

To compare the efficacy and cost-effectiveness of high and low dose regimens of I-131 treatment in patients with hyperthyroidism. One hundred fifty patients with proven hyperthyroidism were randomly allocated into the high (74 patients) and low (76 patients) dose regimen of I-131 treatment. Four patients of the high dose group and one patient of the low dose group were excluded because of lost follow-up. A gland-specific dosage was calculated on the estimated weight of thyroid gland and 24-hour I-131 uptake. The high and low I-131 dose regimens were 150 microCi/gm and 100 microCi/gm, respectively. The first mean radioiodine activity administered to the high and low dose group was 10.2 and 8 mCi, respectively. Repeated treatment was given to 25 patients of the high dose group and 40 patients of the low dose group. Clinical outcome and calculated costs for outpatient attendances, and laboratory tests together with initial and subsequent treatments were evaluated for one year after I-131 treatment. Elimination of hyperthyroidism that resulted in either euthyroidism or hypothyroidism was classified as therapeutic success. The cost effectiveness was also compared. At 6 months after treatment, 45 (64.3%) patients receiving high dose and 59 (78.7%) patients receiving low dose were hyperthyroidism. Clinical outcome at one year showed persistence of hyperthyroidism in 21 (30%) patients of the high dose regimen and 36 (48%) patients of the low dose regimen. At one year post treatment, it was demonstrated that the high dose regimen could eliminate hyperthyroidism in a significantly shorter time than the low dose regimen, i.e., 259.6 days and 305.5 days, respectively, p = 0.008). For the persistent hyperthyroid patients, the average total cost of treatment in the low dose group was significantly higher than that of the high dose group, i.e., 13,422.78 baht and 10,942.79 baht, respectively; p = 0.050). A high dose regimen of radioactive iodine treatment is more effective than

Effects of low doses of caffeine on cognitive performance, mood and thirst in low and higher caffeine consumers.

Science.gov (United States)

Smit, H J; Rogers, P J

2000-10-01

Caffeine is present in many widely consumed drinks and some foods. In the fairly extensive literature on the psychostimulant effects of caffeine, there are few dose-response studies and even fewer studies of the effects of doses of caffeine lower than 50 mg (the range of the amounts of caffeine contained in, for example, a typical serving of tea or cola). This study measured the effects of 0, 12.5, 25, 50 and 100 mg caffeine on cognitive performance, mood and thirst in adults with low and moderate to high habitual caffeine intakes. This was a double-blind, within-subjects study. Following overnight caffeine abstinence, participants (n=23) completed a test battery once before and three times after placebo or caffeine administration. The test battery consisted of two performance tests, a long duration simple reaction time task and a rapid visual information processing task, and a mood questionnaire (including also an item on thirst). Effects on performance and mood confirmed a psychostimulant action of caffeine. All doses of caffeine significantly affected cognitive performance, and the dose-response relationships for these effects were rather flat. The effects on performance were more marked in individuals with a higher level of habitual caffeine intake, whereas caffeine increased thirst only in low caffeine consumers. After overnight caffeine abstinence, caffeine can significantly affect cognitive performance, mood and thirst at doses within and even lower than the range of amounts of caffeine contained in a single serving of popular caffeine-containing drinks. Regular caffeine consumers appear to show substantial tolerance to the thirst-increasing but not to the performance and mood effects of caffeine.

Estimation of effective dose for children in interventional cardiology

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S. S. Sarycheva

2017-01-01

Full Text Available This study is devoted to the estimation of effective dose for children undergoing interventional cardiology examinations. The conversion coefficients (CC from directly measured dose area product (DAP value to effective dose (ED were calculated within the approved effective dose assessment methodology (Guidelines 2.6.1. 2944-11. The CC, Ed K , [mSv / (Gy • cm2] for newborn infants and children of 1, 5, 10 and 15 years old (main(range were calculated as 2.5 (1.8-3.2; 1.1 (0.8-1.3; 0.6 (0.4-0.7; 0.4 (0.3-0.5; and 0,22 (0,18-0,30 respectively. A special Finnish computer program PCXMC 2.0 was used for calculating the dose CC. The series of calculations were made for different values of the physical and geometrical parameters based on their real-existing range of values. The value of CC from DAP to ED were calculated for all pediatric age groups. This work included 153 pediatric interventional studies carried out in two hospitals of the city of St. Petersburg for the period of one year from the summer of 2015. The dose CC dependency from the patient’s age and parameters of the examinations were under the study. The dependence from the beam quality (filtration and tube voltage and age of the patient were found. The younger is the patient, stronger is the filtration and higher is the voltage, the higher is the CC value. The CC in the younger (newborn and older (15 years age groups are different by the factor of 10. It was shown that the changes of the geometric parameters (in the scope of their real existing range have small effect on the value of the effective dose, not exceed 30-50% allowable for radiation protection purpose. The real values of effective doses of children undergoing cardiac interventions were estimated. In severe cases, the values of ED can reach several tens of mSv.

Effects of two different high doses of irradiation on antioxidant system in the liver of guinea pigs.

Science.gov (United States)

Guney, Yildiz; Bukan, Neslihan; Dizman, Aysen; Hicsonmez, Ayse; Bilgihan, Ayse

2004-03-01

To examine the state of the oxidant-antioxidant system in the liver of guinea pig caused by high doses of ionizing radiation in the early period. The research was carried out on guinea pigs irradiated with the doses of 8 Gy (group 2) or 15 Gy (group 3) (single dose/whole body) in comparison with control group (group 1). The levels of thiobarbituric acid reactive substances (TBARS) and glutathione (GSH), the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and the levels of selenium in the liver were measured. TBARS levels in the irradiated animals were markedly higher than those in controls. In group 3, GSH levels and GSH-Px activity were significantly increased while activity of SOD and CAT were significantly decreased compared to groups 1 and 2. Liver selenium levels were not influenced by irradiation. The data have shown that gamma-irradiation at the doses of 8 Gy or 15 Gy results in significant increase in free radical formation while antioxidant enzymes were affected only at a dose of 15 Gy.

Trends in doses to radiation workers recorded on the Central Index of Dose Information

International Nuclear Information System (INIS)

Greenslade, E.; Kendall, G.M.; Fillary, K.; Bines, W.P.

1991-01-01

This paper presents a preliminary analysis of the doses stored on the Central Index of Dose Information for the calendar years 1986, 1987 and 1988. Mean doses are low, and both mean doses and the proportion of workers exceeding 15 mSv in a year are decreasing with time. Underground miners are the occupational group receiving the highest doses, though in this and other relatively high dose groups the exposures are falling with time. Only 6% of workers are female and their average individual dose is about half that of men. Patterns of employment are different for women and men but there is a tendency for women to receive lower doses than men even within the same occupation. (author)

Collaborative learning in higher education : design, implementation and evaluation of group learning activities

NARCIS (Netherlands)

Hei, de M.S.A.

2016-01-01

In higher education, group learning activities (GLAs) are frequently implemented in online, blended or face-to-face educational contexts. A major problem for the design and implementation of good quality GLAs that lead to the desired learning outcomes is that many approaches to GLAs have been

Tramadol Versus Low Dose Tramadol-paracetamol for Patient Controlled Analgesia During Spinal Vertebral Surgery

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Esad Emir

2010-06-01

Full Text Available Pain intensity may be high in the postoperative period after spinal vertebral surgery. The aim of the study was to compare the effectiveness and cost of patient controlled analgesia (PCA with tramadol versus low dose tramadol-paracetamol on postoperative pain. A total of 60 patients were randomly divided into two groups. One group received 1.5 mg/kg tramadol (Group T while the other group received 0.75 mg/kg tramadol plus 1 g of paracetamol (Group P intravenously via a PCA device immediately after surgery and the patients were transferred to a recovery room, Tramadol was continuously infused at a rate of 0.5 mL/h in both groups, at a dose of 10 mg/mL in Group T and 5 mg/mL in Group P. The bolus and infusion programs were adjusted to administer a 1 mL bolus dose of tramadol with a lock time of 10 minutes. In Group P, 1 g of paracetamol was injected intravenously every 6 hours. The four-point nausea scale, numeric rating scale for pain assessment, Ramsey sedation scale, blood pressure, heart rate, respiration rate, peripheral oxygen saturation values and side effects were recorded at 0, 15 and 30 minutes, and at 1, 2, 4, 6, 12, 18 and 24 hours. The time to reach an Aldrete score of 9 was also recorded. A cost analysis for both groups was performed. In Group P, the numeric rating scale scores were significantly lower than that in Group T at 0 and 15 minutes. The number of side effects, additional analgesic requirement and the total dose of tramadol were lower in Group P than in Group T. However, the total cost of postoperative analgesics was significantly higher in Group P than in Group T (p < 0.001. We conclude that PCA using tramadol-paracetamol could be used safely for postoperative pain relief after spinal vertebral surgery, although at a higher cost than with tramadol alone.

A clinical comparison of high dose and low dose of Suxamethonium

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RK Yadav

2014-01-01

Full Text Available Background: Suxamethonium having its rapid onset and short duration of action makes this drug unique amongst the neuromuscular blocking drugs described so far. However, use of suxamethonium is associated with a large number of undesirable side effects. Objective: To evaluate clinical effects of high and low dose of suxamethonium and to determine whether lower dose of suxamethonium can be used for any beneficial effects in terms of its various adverse effects e.g. cardiovascular responses, post-operative muscle pains and intraocular pressure. Methods: A total of 100 patients were included in this prospective study. All these patients on preoperative clinical evaluation were assessed to have adequate airway. All the patients were divided in two groups, low dose group (group I and High dose group (group II with 50 patients in each at random. A standard anesthetic technique was adhered to all the patients and following parameters were observed on comparative basis: a. Fasciculation and post operative myalgia. b. Cardiovascular effects, c. Intraocular pressure. Observation: The incidence of post Suxamethonium pain was significantly greater in group II. Increase in heart rate from baseline was significant in both groups. There was no significant difference between the two groups in the diastolic pressure but rise in systolic blood pressure was significant at all assessment times in both groups. This rise from control was statistically significant. Conclusion: Suxamethonium can be used in lower doses (0.5 mg/kg in elective cases without airway compromise. It gives benefits of reduced muscle pains, cardiovascular responses and intraocular hypertension. Journal of College of Medical Sciences-Nepal, 2013, Vol-9, No-2, 1-8 DOI: http://dx.doi.org/10.3126/jcmsn.v9i2.9677

Do Asian renal transplant patients need another mycophenolate mofetil dose compared with Caucasian or African American patients?

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Li, Pengmei; Shuker, Nauras; Hesselink, Dennis A; van Schaik, Ron H N; Zhang, Xianglin; van Gelder, Teun

2014-10-01

Mycophenolate mofetil (MMF) is used to prevent acute rejection following solid organ transplantation in transplant centers all over the world. Patients from different ethnic backgrounds are treated with this drug, for which therapeutic drug monitoring (TDM) has not become the standard of practice in most centers. Whether or not some ethnic groups require a different MMF dose has been a topic of debate in recent years. In this review, it is shown that Asian patients, compared with Caucasian patients, with a comparable MMF dose reach higher mycophenolic acid (MPA) exposure. Also clinical experience points toward more adverse events in case of treatment with 1 g MMF bid in Asian patients, and therefore, for this ethnic group, a lower maintenance dose seems justified. In contrast, African American patients reach similar drug concentrations as Caucasians patients receiving the same MMF dose, but due to immunological reasons, they require a higher MMF dose to reach comparable acute rejection incidences. When TDM is performed, clinicians can correct the dose and compensate for interethnic differences in drug exposure. Otherwise, it is important to choose the right dose. This optimal dose is 20-46% lower in Asian transplant recipients than in Caucasian or African American patients. © 2014 Steunstichting ESOT.

Population doses from terrestrial gamma exposure in China

Energy Technology Data Exchange (ETDEWEB)

Ren, T.; Wang, Z.; Zhu, C. (Ministry of Public Health, Beijing, BJ (China))

1992-01-01

In order to estimate terrestrial gamma radiation exposure three nationwide surveys have been completed since 1981. The population-weighted outdoor and indoor arithmetic means of gamma dose rate based on momentary dose rate measurements using a NaI(Tl) environmental radiation meter and high-pressure ionisation chamber are, respectively, 80.3 nGy.h[sup -1] and 120 nGy.h[sup -1]. Based on integrating dose measurement using TLD CaSO[sub 4]/Dy they are 67 nGy.h[sup -1] and 89 nGy.h[sup -1] respectively, and based on natural radionuclides concentrations in soil, determined by gamma spectroscopy analyses, they are 72.8 nGy.h[sup -1] and 102 nGy.h[sup -1], respectively. These surveys were conducted independently by different groups. The best estimations of population-weighted gamma dose rates in China, based on all these surveys, would be 70 nGy.h[sup -1] and 98 nGy.h[sup -1] for outdoors and indoors, respectively. The annual average of effective dose equivalent is 0.56 mSv. These values are higher than the world averages estimated by UNSCEAR. The main reason is that the concentrations of [sup 232]Th and [sup 40]K in the soil of China are much higher than the world average estimated. (author).

High-dose radioiodine therapy of Graves disease

International Nuclear Information System (INIS)

Solodky, V.; Fomin, D.; Pestritskaya, E.

2015-01-01

edema of the neck area condition, which was blocked in a course of 3 to 5 days, without any additional prescriptions. In the control group, 1 patient complained of the same condition. Conclusion: implementing a high-dose RIT provides a 21% higher probability of Graves disease recovery as well as a four-time as much decline in relapse occurrences, with an equally favourable tolerance. (authors)

Image guidance doses delivered during radiotherapy: Quantification, management, and reduction: Report of the AAPM Therapy Physics Committee Task Group 180.

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Ding, George X; Alaei, Parham; Curran, Bruce; Flynn, Ryan; Gossman, Michael; Mackie, T Rock; Miften, Moyed; Morin, Richard; Xu, X George; Zhu, Timothy C

2018-05-01

With radiotherapy having entered the era of image guidance, or image-guided radiation therapy (IGRT), imaging procedures are routinely performed for patient positioning and target localization. The imaging dose delivered may result in excessive dose to sensitive organs and potentially increase the chance of secondary cancers and, therefore, needs to be managed. This task group was charged with: a) providing an overview on imaging dose, including megavoltage electronic portal imaging (MV EPI), kilovoltage digital radiography (kV DR), Tomotherapy MV-CT, megavoltage cone-beam CT (MV-CBCT) and kilovoltage cone-beam CT (kV-CBCT), and b) providing general guidelines for commissioning dose calculation methods and managing imaging dose to patients. We briefly review the dose to radiotherapy (RT) patients resulting from different image guidance procedures and list typical organ doses resulting from MV and kV image acquisition procedures. We provide recommendations for managing the imaging dose, including different methods for its calculation, and techniques for reducing it. The recommended threshold beyond which imaging dose should be considered in the treatment planning process is 5% of the therapeutic target dose. Although the imaging dose resulting from current kV acquisition procedures is generally below this threshold, the ALARA principle should always be applied in practice. Medical physicists should make radiation oncologists aware of the imaging doses delivered to patients under their care. Balancing ALARA with the requirement for effective target localization requires that imaging dose be managed based on the consideration of weighing risks and benefits to the patient. © 2018 American Association of Physicists in Medicine.

Is It Better to Enter a Volume CT Dose Index Value before or after Scan Range Adjustment for Radiation Dose Optimization of Pediatric Cardiothoracic CT with Tube Current Modulation?

Science.gov (United States)

2018-01-01

Objective To determine whether the body size-adapted volume computed tomography (CT) dose index (CTDvol) in pediatric cardiothoracic CT with tube current modulation is better to be entered before or after scan range adjustment for radiation dose optimization. Materials and Methods In 83 patients, cardiothoracic CT with tube current modulation was performed with the body size-adapted CTDIvol entered after (group 1, n = 42) or before (group 2, n = 41) scan range adjustment. Patient-related, radiation dose, and image quality parameters were compared and correlated between the two groups. Results The CTDIvol after the CT scan in group 1 was significantly higher than that in group 2 (1.7 ± 0.1 mGy vs. 1.4 ± 0.3 mGy; p Hounsfield units [HU] vs. 4.5 ± 0.7 HU) and image quality (1.5 ± 0.6 vs. 1.5 ± 0.6) showed no significant differences between the two (p > 0.05). In both groups, all patient-related parameters, except body density, showed positive correlations (r = 0.49–0.94; p 0.05) in group 2. Conclusion In pediatric cardiothoracic CT with tube current modulation, the CTDIvol entered before scan range adjustment provides a significant dose reduction (18%) with comparable image quality compared with that entered after scan range adjustment.

Dose survival of G0 lymphocytes irradiated in vitro: A test for a possible population bias in the cohort of atomic-bomb survivors exposed to high doses

International Nuclear Information System (INIS)

Nakamura, Nori; Sposto, R.; Akiyama, Mitoshi.

1993-04-01

An in-vitro colony assay was employed for X-ray dose-survival studies of peripheral-blood lymphocytes from 117 Adult Health Study participants with Dosimetry System 1986 doses 10 values (the X-ray dose required to kill 90% of cells) for these two groups were 3.40 Gy (7.5%) and 3.34 Gy (7.8%), respectively. No statistically significant differences in their distributions were detected. In addition, neither sex nor age affected the in-vitro radiosensitivity of lymphocytes for either group or for all subjects combined. Therefore it was concluded that, as far as the G 0 -lymphocyte colony assay is concerned, there is no evidence for preferential loss of individuals with higher cellular radiosensitivity among the high-dose atomic bomb survivors. However, it should be noted that the interindividual variations in cellular radiosensitivity were not large compared with the experimental variations. Consequently, the above-mentioned results should be considered due to the small heterogeneity of lymphocyte radiosensitivity among the survivors. (J.P.N.)

Radiation Therapy for Bone Metastases from Hepatocellular Carcinoma: Effect of Radiation Dose Escalation

International Nuclear Information System (INIS)

Kim, Tae Gyu; Park, Hee Chul; Lim, Do Hoon

2011-01-01

To evaluate the extent of pain response and objective response to palliative radiotherapy (RT) for bone metastases from hepatocellular carcinoma according to RT dose. From January 2007 to June 2010, palliative RT was conducted for 103 patients (223 sites) with bone metastases from hepatocellular carcinoma. Treatment sites were divided into the high RT dose and low RT dose groups by biologically effective dose (BED) of 39 Gy10. Pain responses were evaluated using the numeric rating scale. Pain scores before and after RT were compared and categorized into 'Decreased', 'No change' and 'increased'. Radiological objective responses were categorized into complete response, partial response, stable disease and progression using modified RECIST (Response Evaluation Criteria In Solid Tumors) criteria; the factors predicting patients' survival were analyzed. The median follow-up period was 6 months (range, 0 to 46 months), and the radiologic responses existed in 67 RT sites (66.3%) and 44 sites (89.8%) in the high and low RT dose group, respectively. A dose-response relationship was found in relation to RT dose (p=0.02). Pain responses were 75% and 65% in the high and low RT dose groups, respectively. However, no statistical difference in pain response was found between the two groups (p=0.24). There were no differences in the toxicity profiles between the high and low RT dose groups. Median survival from the time of bone metastases diagnosis was 11 months (range, 0 to 46 months). The Child-Pugh classification at the time of palliative RT was the only significant predictive factor for patient survival after RT. Median survival time was 14 months under Child-Pugh A and 2 months under Child-Pugh B and C. The rate of radiologic objective response was higher in the high RT dose group. Palliative RT with a high dose would provide an improvement in patient quality of life through enhanced tumor response, especially in patients with proper liver function.

Ultra-rapid high dose irradiation schedules for the palliation of brain metastases: final results of the first two studies by the radiation therapy oncology group

International Nuclear Information System (INIS)

Borgelt, B.; Gelber, R.; Larson, M.; Hendrickson, F.; Griffin, T.; Rother, R.

1981-01-01

Between January, 1971, and February, 1976, the Radiation Therapy Oncology Group entered 1902 evaluable patients into two sequential Phase III national cooperative trials to study the effectiveness of different time dose radiotherapy schemes on the palliation of patients with brain metastases. Each trial included an optional arm into which patients were randomized to receive 1000 rad/1 fraction (26 patients, First study) or 1200 rad/2 fractions (33 patients, Second study). Comparisons were made with 143 control patients randomized by the same participating institutions to receive a more protracted course of irradiation (2000, 3000 or 4000 rad/1-4wks). Response of patients receiving ultra-rapid treatment, as assessed by the percent who had improvement in neurologic function, was comparable to that of patients receiving the more protracted schedules. Promptness of neurologic function improvement, treatment morbidity and median survival were also comparable to those of patients receiving 2000 to 4000 rad. However, the duration of improvement, time to progression of neurologic status and rate of complete disappearance of neurologic symptoms were generally less for those patients who received 1000 or 1200 rad. These results suggest that ultra-rapid, high dose irradiation schedules may not be so effective as higher dose schedules in the palliation of patients with brain metastases

Quality control of 192Ir high dose rate after loading brachytherapy dose veracity

International Nuclear Information System (INIS)

Feng Zhongsu; Xu Xiao; Liu Fen

2008-01-01

Recently, 192 Ir high dose rate (HDR) afterloading are widely used in brachytherapy. The advantage of using HDR systems over low dose rate systems are shorter treatment time and higher fraction dose. To guarantee the veracity of the delivery dose, several quality control methods are deseribed in this work. With these we can improve the position precision, time precision and dose precision of the brachytherapy. (authors)

Evaluation of the repeated-dose liver micronucleus assay using N-nitrosomorpholine in young adult rats: report on collaborative study by the Collaborative Study Group for the Micronucleus Test (CSGMT)/Japanese Environmental Mutagen Society (JEMS)-Mammalian Mutagenicity Study (MMS) Group.

Science.gov (United States)

Hayashi, Aya; Kosaka, Mizuki; Kimura, Aoi; Wako, Yumi; Kawasako, Kazufumi; Hamada, Shuichi

2015-03-01

The present study was conducted to evaluate the suitability of a repeated-dose liver micronucleus (LMN) assay in young adult rats as a collaborative study by the Mammalian mutagenicity study (MMS) group. All procedures were performed in accordance with the standard protocols of the MMS Group. Six-week-old male Crl:CD(SD) rats (5 animals/group) received oral doses of the hepatocarcinogen N-nitrosomorpholine (NMOR) at 0 (control), 5, 10, and 30mg/kg/day (10mL/kg) for 14 days. Control animals received vehicle (water). Hepatocytes were collected from the liver 24h after the last dose, and the number of micronucleated hepatocytes (MNHEPs) was determined by microscopy. The number of micronucleated immature erythrocytes (MNIMEs) in the femoral bone marrow was also determined. The liver was examined using histopathologic methods after formalin fixation. The results showed statistically significant and dose-dependent increases in the number of MNHEPs in the liver at doses of 10mg/kg and greater when compared with the vehicle control. However, no significant increase was noted in the number of MNIMEs in the bone marrow at doses of up to 30mg/kg. Histopathology of the liver revealed hypertrophy and single cell necrosis of hepatocytes at doses of 5mg/kg and above. These results showed that the induction of micronuclei by NMOR was detected by the repeated-dose LMN assay, but not by the repeated-dose bone marrow micronucleus assay. Copyright © 2014 Elsevier B.V. All rights reserved.

Patterns of prednisone use during pregnancy in women with rheumatoid arthritis: Daily and cumulative dose.

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Palmsten, Kristin; Rolland, Matthieu; Hebert, Mary F; Clowse, Megan E B; Schatz, Michael; Xu, Ronghui; Chambers, Christina D

2018-04-01

To characterize prednisone use in pregnant women with rheumatoid arthritis using individual-level heat-maps and clustering individual trajectories of prednisone dose, and to evaluate the association between prednisone dose trajectory groups and gestational length. This study included pregnant women with rheumatoid arthritis who enrolled in the MotherToBaby Autoimmune Diseases in Pregnancy Study (2003-2014) before gestational week 20 and reported prednisone use without another oral glucocorticoid during pregnancy (n = 254). Information on medication use and pregnancy outcomes was collected by telephone interview plus by medical record review. Prednisone daily dose and cumulative dose were plotted by gestational day using a heat map for each individual. K-means clustering was used to cluster individual trajectories of prednisone dose into groups. The associations between trajectory group and demographics, disease severity measured by the Health Assessment Questionnaire at enrollment, and gestational length were evaluated. Women used prednisone 3 to 292 days during pregnancy, with daily doses ranging from <1 to 60 mg. Total cumulative dose ranged from 8 to 6225 mg. Disease severity, non-biologic disease modifying anti-rheumatic drug use, and gestational length varied significantly by trajectory group. After adjusting for disease severity, non-biologic disease modifying anti-rheumatic drug use, and other covariates, the highest vs lowest daily dose trajectory group was associated with reduced gestational age at delivery (β: -2.3 weeks (95%: -3.4, -1.3)), as was the highest vs lowest cumulative dose trajectory group (β: -2.6 weeks (95%: -3.6, -1.5)). In pregnant women with rheumatoid arthritis, patterns of higher prednisone dose were associated with shorter gestational length compared with lower dose. Copyright © 2018 John Wiley & Sons, Ltd.

Effects of first-dose volume and exercise on the efficacy and tolerability of bowel preparations for colonoscopy in Chinese people

Directory of Open Access Journals (Sweden)

Qin Y

2016-04-01

Full Text Available Ying Qin, Wei Liu, Songbai Lin, Xiangfeng Li International Medical Services, Peking Union Medical College Hospital, Beijing, People’s Republic of China Aim: This study was designed to compare the efficacy and tolerability of bowel preparations with and without the higher first-dose volume of polyethylene glycol (PEG solution or exercise after drinking PEG solution in Chinese people. Methods: A total of 330 participants who had a colonoscopy done in Peking Union Medical College Hospital were randomly and evenly assigned to three groups. Participants in Group A ingested 1 L PEG solution and then ingested 2 L PEG solution at a rate of 250 mL every 15 minutes. Participants in Group B ingested 3 L PEG solution at a rate of 250 mL every 15 minutes and then exercised more than 10 minutes after ingesting each liter of PEG solution. Participants in Group C ingested 3 L PEG solution at a rate of 250 mL every 15 minutes. Experienced gastrointestinal endoscopists rated the efficacy of bowel preparations based on the Boston Bowel Preparation Scale score. A questionnaire regarding participants’ symptoms associated with bowel preparations was administered to evaluate participants’ tolerability. Results: The three groups had insignificant difference in the percentages of participants’ symptoms including dizziness, nausea, stomach ache, bloating, and asthenia. However, the percentages of participants having hunger sensation, sleep disturbance, and anal discomfort were significantly higher in groups with the higher first-dose volume of PEG solution or exercise after drinking PEG solution than without them. The three groups had insignificant difference in the Boston Bowel Preparation Scale score. Conclusion: Whether to add the higher first-dose volume of PEG solution and exercise after drinking PEG solution or not, all participants achieved a similar quality of bowel preparations. Bowel preparations without the additional first-dose volume of PEG

Increasing the dose of television advertising in a national antismoking media campaign: results from a randomised field trial.

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McAfee, Tim; Davis, Kevin C; Shafer, Paul; Patel, Deesha; Alexander, Robert; Bunnell, Rebecca

2017-01-01

While antismoking media campaigns have demonstrated effectiveness, less is known about the country-level effects of increased media dosing. The 2012 US Tips From Former Smokers (Tips) campaign generated approximately 1.6 million quit attempts overall; however, the specific dose-response from the campaign was only assessed by self-report. Assess the impact of higher ad exposure during the 2013 Tips campaign on quit-related behaviours and intentions, campaign awareness, communication about campaign, and disease knowledge. A 3-month national media buy was supplemented within 67 (of 190) randomly selected local media markets. Higher-dose markets received media buys 3 times that of standard-dose markets. We compared outcomes of interest using data collected via web-based surveys from nationally representative, address-based probability samples of 5733 cigarette smokers and 2843 non-smokers. In higher-dose markets, 87.2% of smokers and 83.9% of non-smokers recalled television campaign exposure versus 75.0% of smokers and 73.9% of non-smokers in standard-dose markets. Among smokers overall, the relative quit attempt rate was 11% higher in higher-dose markets (38.8% vs 34.9%; pmedia campaign compared standard and higher doses by randomisation of local media markets. Results demonstrate the effectiveness of a higher dose for engaging non-smokers and further increasing quit attempts among smokers, especially African-Americans. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Effective dose and dose to crystalline lens during angiographic procedures

International Nuclear Information System (INIS)

Pages, J.

1998-01-01

The highest radiation doses levels received by radiologists are observed during interventional procedures. Doses to forehead and neck received by a radiologist executing angiographic examinations at the department of radiology at the academic hospital (AZ-VUB) have been measured for a group of 34 examinations. The doses to crystalline lens and the effective doses for a period of one year have been estimated. For the crystalline lens the maximum dose approaches the ICRP limit, that indicates the necessity for the radiologist to use leaded glasses. (N.C.)

Serum total homocystein, folate and vitamin B12 levels and their correlation with antipsychotic drug doses in adult male patients with chronic schizophrenia.

Science.gov (United States)

Eren, Esin; Yeğin, Ayşenur; Yilmaz, Necat; Herken, Hasan

2010-01-01

Elevated blood levels of homocysteine (hCY) have been associated with schizophrenic male patients. However, controversy remains regarding the association between lowered plasma folate and vitamin B12, hyperhomocysteinemia, and schizophrenia. Sixty-six (66) male patients with chronic schizophrenia were investigated to test the hypotheses that alterations in Hcy, folate, and vitamin B12 levels might be related to the antipsychotic drug doses used in treatment. Serum total homocysteine, folic acid, and vitamin B12 levels were determined by chemiluminescence methods in both patients and control subjects. The patients were grouped according to the antipsychotic drug doses used in their treatment. Patients had higher homocysteine levels but they did not differ from controls in terms of folate and vitamin B12 levels. On the other hand, only folate levels were negatively correlated in the patient group treated with higher therapeutic doses of chlorpromazine equivalents (> 400 mg/day) compared to the patient group with lower doses (< 400 mg/day). Our findings show that higher typical antipsychotic drugs may play a role as modifiying factor for folate metabolism in chronic schizoprenic male patients.

Radiation dose and image quality of X-ray volume imaging systems: cone-beam computed tomography, digital subtraction angiography and digital fluoroscopy.

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Paul, Jijo; Jacobi, Volkmar; Farhang, Mohammad; Bazrafshan, Babak; Vogl, Thomas J; Mbalisike, Emmanuel C

2013-06-01

Radiation dose and image quality estimation of three X-ray volume imaging (XVI) systems. A total of 126 patients were examined using three XVI systems (groups 1-3) and their data were retrospectively analysed from 2007 to 2012. Each group consisted of 42 patients and each patient was examined using cone-beam computed tomography (CBCT), digital subtraction angiography (DSA) and digital fluoroscopy (DF). Dose parameters such as dose-area product (DAP), skin entry dose (SED) and image quality parameters such as Hounsfield unit (HU), noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were estimated and compared using appropriate statistical tests. Mean DAP and SED were lower in recent XVI than its previous counterparts in CBCT, DSA and DF. HU of all measured locations was non-significant between the groups except the hepatic artery. Noise showed significant difference among groups (P < 0.05). Regarding CNR and SNR, the recent XVI showed a higher and significant difference compared to its previous versions. Qualitatively, CBCT showed significance between versions unlike the DSA and DF which showed non-significance. A reduction of radiation dose was obtained for the recent-generation XVI system in CBCT, DSA and DF. Image noise was significantly lower; SNR and CNR were higher than in previous versions. The technological advancements and the reduction in the number of frames led to a significant dose reduction and improved image quality with the recent-generation XVI system. • X-ray volume imaging (XVI) systems are increasingly used for interventional radiological procedures. • More modern XVI systems use lower radiation doses compared with earlier counterparts. • Furthermore more modern XVI systems provide higher image quality. • Technological advances reduce radiation dose and improve image quality.

Persistence of Meningococcal Antibodies and Response to a Third Dose After a Two-dose Vaccination Series with Investigational MenABCWY Vaccine Formulations in Adolescents.

Science.gov (United States)

Saez-Llorens, Xavier; Aguilera Vaca, Diana Catalina; Abarca, Katia; Maho, Emmanuelle; Han, Linda; Smolenov, Igor; Dull, Peter

2015-10-01

In a primary study, healthy adolescents received 2 doses (months 0/2) of 1 of the 4 investigational meningococcal ABCWY vaccine formulations, containing components of licensed quadrivalent glycoconjugate vaccine MenACWY-CRM, combined with different amounts of recombinant proteins (rMenB) and outer membrane vesicles (OMV) from a licensed serogroup B vaccine, or 2 doses of rMenB alone or 1 dose of MenACWY-CRM then a placebo. This phase 2 extension study evaluated antibody persistence up to 10 months after the 2-dose series and the immunogenicity and safety of a third dose (month 6). Immune responses against serogroups ACWY and serogroup B test strains were measured by serum bactericidal assay with human complement. At month 12, antibody persistence against serogroups ACWY in all 2-dose MenABCWY groups was at least comparable with the 1-dose MenACWY-CRM group. Bactericidal antibodies against most serogroup B test strains declined by month 6, then plateaued over the subsequent 6 months, with overall higher antibody persistence associated with OMV-containing formulations. A third MenABCWY vaccine dose induced robust immune responses against vaccine antigens, although antibody levels 6 months later were comparable with those observed 5 months after the 2-dose series. All investigational MenABCWY vaccines were well tolerated. Two or three doses of investigational MenABCWY vaccines elicited immune responses against serogroups ACWY that were at least comparable with those after 1 dose of MenACWY-CRM. After either vaccination series, investigational MenABCWY vaccine formulations containing OMV had the highest immunogenicity against most serogroup B test strains. No safety concerns were identified in this study.

Comparison of scatter doses from a multislice and a single slice CT scanner

International Nuclear Information System (INIS)

Burrage, J. W.; Causer, D. A.

2006-01-01

During shielding calculations for a new multislice CT (MSCT) scanner it was found that the manufacturer's data indicated significantly higher external scatter doses than would be generated for a single slice CT (SSCT). Even allowing for increased beam width, the manufacturer's data indicated that the scatter dose per scan was higher by a factor of about 3 to 4. The magnitude of the discrepancy was contrary to expectations and also contrary to a statement by the UK ImPACT group, which indicated that when beam width is taken into account, the scatter doses should be similar. The matter was investigated by comparing scatter doses from an SSCT and an MSCT. Scatter measurements were performed at three points using a standard perspex CTDI phantom, and CT dose indices were also measured to compare scanner output. MSCT measurements were performed with a 40 mm wide beam, SSCT measurements with a 10 mm wide beam. A film badge survey was also performed after the installation of the MSCT scanner to assess the adequacy of lead shielding in the room. It was found that the scatter doses from the MSCT were lower than indicated by the manufacturer's data. MSCT scatter doses were approximately 4 times higher than those from the SSCT, consistent with expectations due to beam width differences. The CT dose indices were similar, and the film badge survey indicated that the existing shielding, which had been adequate for the SSCT, was also adequate for the MSCT

A phase 2a randomized, parallel group, dose-ranging study of molindone in children with attention-deficit/hyperactivity disorder and persistent, serious conduct problems.

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Stocks, Jennifer Dugan; Taneja, Baldeo K; Baroldi, Paolo; Findling, Robert L

2012-04-01

To evaluate safety and tolerability of four doses of immediate-release molindone hydrochloride in children with attention-deficit/hyperactivity disorder (ADHD) and serious conduct problems. This open-label, parallel-group, dose-ranging, multicenter trial randomized children, aged 6-12 years, with ADHD and persistent, serious conduct problems to receive oral molindone thrice daily for 9-12 weeks in four treatment groups: Group 1-10 mg (5 mg if weight conduct problems. Secondary outcome measures included change in Nisonger Child Behavior Rating Form-Typical Intelligence Quotient (NCBRF-TIQ) Conduct Problem subscale scores, change in Clinical Global Impressions-Severity (CGI-S) and -Improvement (CGI-I) subscale scores from baseline to end point, and Swanson, Nolan, and Pelham rating scale-revised (SNAP-IV) ADHD-related subscale scores. The study randomized 78 children; 55 completed the study. Treatment with molindone was generally well tolerated, with no clinically meaningful changes in laboratory or physical examination findings. The most common treatment-related adverse events (AEs) included somnolence (n=9), weight increase (n=8), akathisia (n=4), sedation (n=4), and abdominal pain (n=4). Mean weight increased by 0.54 kg, and mean body mass index by 0.24 kg/m(2). The incidence of AEs and treatment-related AEs increased with increasing dose. NCBRF-TIQ subscale scores improved in all four treatment groups, with 34%, 34%, 32%, and 55% decreases from baseline in groups 1, 2, 3, and 4, respectively. CGI-S and SNAP-IV scores improved over time in all treatment groups, and CGI-I scores improved to the greatest degree in group 4. Molindone at doses of 5-20 mg/day (children weighing <30 kg) and 20-40 mg (≥ 30 kg) was well tolerated, and preliminary efficacy results suggest that molindone produces dose-related behavioral improvements over 9-12 weeks. Additional double-blind, placebo-controlled trials are needed to further investigate molindone in this pediatric population.

The consequences of a reduction in the administratively applied maximum annual dose equivalent level for an individual in a group of occupationally exposed workers

International Nuclear Information System (INIS)

Harrison, N.T.

1980-02-01

An analysis is described for predicting the consequences of a reduction in the administratively applied maximum dose equivalent level to individuals in a group of workers occupationally exposed to ionising radiations, for the situation in which no changes are made to the working environment. This limitation of the maximum individual dose equivalent is accommodated by allowing the number of individuals in the working group to increase. The derivation of the analysis is given, together with worked examples, which highlight the important assumptions that have been made and the conclusions that can be drawn. The results are obtained in the form of the capacity of the particular working environment to accommodate the limitation of the maximum individual dose equivalent, the increase in the number of workers required to carry out the productive work and any consequent increase in the occupational collective dose equivalent. (author)

Comparison between a single dose of goserelin (depot) and multiple daily doses of leuprolide acetate for pituitary suppression in IVF treatment: a clinical endocrinological study of the ovarian response.

Science.gov (United States)

Geber, Selmo; Sales, Liana; Sampaio, Marcos A C

2002-07-01

Compare the efficacy and safety of two different GnRHa, used for pituitary suppression in IVF cycles. A total of 292 patients using depot goserelin (Group 1) and 167 using daily leuprolide acetate (Group 2) were compared. Days required to achieve pituitary function suppression, duration of ovarian stimulation, total dose of HMG, number of aspirated follicles, number of oocytes retrieved, and presence of functional ovarian cyst were analyzed. The time taken to achieve downregulation was similar. The mean number of ampoules used for superovulation was higher in Group 1; however, this difference was observed only for patients >40 years old that started GnRHa in the follicular phase. There was no difference between the two groups in the duration of superovulation, in the number of follicles aspirated, and the number of oocytes retrieved. In the group of patients with >40 years the incidence of ovarian cysts was higher in Group 2. Both routes of GnRHa have similar effects for pituitary suppression and ovulation induction in assisted reproductive technology. Therefore the long-acting GnRHa is an excellent option, as only a single subcutaneous dose is necessary, decreasing the risk of the patient to forget its use and, most important, it does not interfere in the patient's quality of life.

''Low dose'' and/or ''high dose'' in radiation protection: A need to setting criteria for dose classification

International Nuclear Information System (INIS)

Sohrabi, M.

1997-01-01

The ''low dose'' and/or ''high dose'' of ionizing radiation are common terms widely used in radiation applications, radiation protection and radiobiology, and natural radiation environment. Reading the title, the papers of this interesting and highly important conference and the related literature, one can simply raise the question; ''What are the levels and/or criteria for defining a low dose or a high dose of ionizing radiation?''. This is due to the fact that the criteria for these terms and for dose levels between these two extreme quantities have not yet been set, so that the terms relatively lower doses or higher doses are usually applied. Therefore, setting criteria for classification of radiation doses in the above mentioned areas seems a vital need. The author while realizing the existing problems to achieve this important task, has made efforts in this paper to justify this need and has proposed some criteria, in particular for the classification of natural radiation areas, based on a system of dose limitation. (author)

IMMUNE RESPONSES OF GOATS (SHAMI BREED TO VACCINATION WITH A FULL, REDUCED AND CONJUNCTIVAL DOSE OF BRUCEVAC (BRUCELLA MELITENSIS REV.1 VACCINE

Directory of Open Access Journals (Sweden)

F. ALDOMY, M. ALKHAWALDEH1 AND I. B. YOUNIS

2009-10-01

Full Text Available Three groups of Shami goats were randomly vaccinated with Brucevac (Rev. 1 vaccine. Group 1 was vaccinated subcutaneously with a full dose (1.54 x 109 organisms. Group 2 was vaccinated conjunctively with one eye drop (5.2 x 108 organisms, while Group 3 was injected subcutaneously with a reduced dose (7.1 x 105 organisms of vaccine. Blood samples were collected before vaccination, two, four, eight, 15 and 24 weeks post vaccination. All samples were tested through CFT, ELISA, SAT and Rose Bengal plate test. All serological tests used detected a higher percentage of vaccinated female kids with a full dose than they did in other groups vaccinated with a reduced dose or with a conjunctival dose of Rev.1 vaccine. The overall results suggested that 100% of animals vaccinated with a conjunctival dose became positive to CFT at two, four, eight and 15 weeks post vaccination, and then the percentage of seropositive animals declined and became 20% at 24 weeks post inoculation. The conjunctival route of vaccination significantly reduced the intensity and duration of the post vaccination serological response, which makes the use of this vaccine compatible with brucellosis programmes, even when these are based on a test-and–slaughter policy. The overall results showed that Shami goats responded to Rev.1 vaccine in the expected way. The majority of animals were seropositive to the CFT by two weeks after vaccination with higher numbers of seropositive animals in the kids group vaccinated with a full dose of Rev.1 vaccine.

Switching From Age-Based Stimulus Dosing to Dose Titration Protocols in Electroconvulsive Therapy: Empirical Evidence for Better Patient Outcomes With Lower Peak and Cumulative Energy Doses.

Science.gov (United States)

O'Neill-Kerr, Alex; Yassin, Anhar; Rogers, Stephen; Cornish, Janie

2017-09-01

The aim of this study was to test the proposition that adoption of a dose titration protocol may be associated with better patient outcomes, at lower treatment dose, and with comparable cumulative dose to that in patients treated using an age-based stimulus dosing protocol. This was an analysis of data assembled from archived records and based on cohorts of patients treated respectively on an age-based stimulus dosing protocol and on a dose titration protocol in the National Health Service in England. We demonstrated a significantly better response in the patient cohort treated with dose titration than with age-based stimulus dosing. Peak doses were less and the total cumulative dose was less in the dose titration group than in the age-based stimulus dosing group. Our findings are consistent with superior outcomes in patients treated using a dose titration protocol when compared with age-based stimulus dosing in a similar cohort of patients.

Clinical study on the adriamycin induced cardiomyopathy using the cardiac magnetic resonance imaging. Total dose and cardiac dysfunction

International Nuclear Information System (INIS)

Yamaguchi, Kyoko; Teraoka, Kunihiko; Hirano, Masaharu

2001-01-01

We studied cardiac functional disorders caused by Adoriamycin using gadolinium (Gd) contrast cine MRI. Forty-eight patients were given ACT (31 men and 17 women; mean age, 52±15 years). First, the relationship between dose and the left ventricular volume, cardiac function, left ventricular cardiac mass and localized wall motion were examined in all patients. Patients given a total dose of 300 mg/m 2 or higher were assigned to the high dose group and those given doses under 300 mg/m 2 to the low dose group. The same parameters were studied in both groups and compared. A 1.5-Tesla superconductive MRI was used for all studies. Cine images of the long and short axes at the papillary muscle level were obtained by ECG R-wave synchronized Gd contrast cine MRI. Left ventricular volume and cardiac function were analyzed using the long-axis cine images and the wall thickness in diastole and systole was measured at each site using the short-axis cine images. The percentage of wall thickness was calculated at each site. The mean ACT dose was 273.3±218.2 mg/m 2 . In all patients the total dose directly correlated with ESVI and inversely correlated with the ejection fraction (EF). In the high dose group, the total dose and EF were inversely correlated, but no significant differences were observed in the low dose group. In the high dose group, the ESVI was significantly greater and the SVI and EF were more significantly reduced than in the low dose group. In the high dose group, the thickness of the anterior, lateral and posterior walls, excluding the septum, was significantly lower than in the low dose group. However, changes in wall thickness were not significantly different between the groups. Gd contrast cine MRI was useful in examining cardiac functional disorders caused by anthracyclines. The total dose of anthracycline correlated directly with the ESVI, and inversely with the EF. A total dose of 300 mg/m 2 appeared to be the borderline dose beyond which there were

Clinical study on the adriamycin induced cardiomyopathy using the cardiac magnetic resonance imaging. Total dose and cardiac dysfunction

Energy Technology Data Exchange (ETDEWEB)

Yamaguchi, Kyoko; Teraoka, Kunihiko; Hirano, Masaharu [Tokyo Medical Coll. (Japan)

2001-05-01

We studied cardiac functional disorders caused by Adoriamycin using gadolinium (Gd) contrast cine MRI. Forty-eight patients were given ACT (31 men and 17 women; mean age, 52{+-}15 years). First, the relationship between dose and the left ventricular volume, cardiac function, left ventricular cardiac mass and localized wall motion were examined in all patients. Patients given a total dose of 300 mg/m{sup 2} or higher were assigned to the high dose group and those given doses under 300 mg/m{sup 2} to the low dose group. The same parameters were studied in both groups and compared. A 1.5-Tesla superconductive MRI was used for all studies. Cine images of the long and short axes at the papillary muscle level were obtained by ECG R-wave synchronized Gd contrast cine MRI. Left ventricular volume and cardiac function were analyzed using the long-axis cine images and the wall thickness in diastole and systole was measured at each site using the short-axis cine images. The percentage of wall thickness was calculated at each site. The mean ACT dose was 273.3{+-}218.2 mg/m{sup 2}. In all patients the total dose directly correlated with ESVI and inversely correlated with the ejection fraction (EF). In the high dose group, the total dose and EF were inversely correlated, but no significant differences were observed in the low dose group. In the high dose group, the ESVI was significantly greater and the SVI and EF were more significantly reduced than in the low dose group. In the high dose group, the thickness of the anterior, lateral and posterior walls, excluding the septum, was significantly lower than in the low dose group. However, changes in wall thickness were not significantly different between the groups. Gd contrast cine MRI was useful in examining cardiac functional disorders caused by anthracyclines. The total dose of anthracycline correlated directly with the ESVI, and inversely with the EF. A total dose of 300 mg/m{sup 2} appeared to be the borderline dose beyond

Dose reduction in evacuation proctography

International Nuclear Information System (INIS)

Hare, C.; Halligan, S.; Bartram, C.I.; Gupta, R.; Walker, A.E.; Renfrew, I.

2001-01-01

The goal of this study was to reduce the patient radiation dose from evacuation proctography. Ninety-eight consecutive adult patients referred for proctography to investigate difficult rectal evacuation were studied using a digital imaging system with either a standard digital program for barium examinations, a reduced dose digital program (both with and without additional copper filtration), or Video fluoroscopy. Dose-area products were recorded for each examination and the groups were compared. All four protocols produced technically acceptable examinations. The low-dose program with copper filtration (median dose 382 cGy cm 2 ) and Video fluoroscopy (median dose 705 cGy cm 2 ) were associated with significantly less dose than other groups (p < 0.0001). Patient dose during evacuation proctography can be reduced significantly without compromising the diagnostic quality of the examination. A digital program with added copper filtration conveyed the lowest dose. (orig.)

Pharmacokinetics of serelaxin in patients with hepatic impairment: a single-dose, open-label, parallel group study.

Science.gov (United States)

Kobalava, Zhanna; Villevalde, Svetlana; Kotovskaya, Yulia; Hinrichsen, Holger; Petersen-Sylla, Marc; Zaehringer, Andreas; Pang, Yinuo; Rajman, Iris; Canadi, Jasna; Dahlke, Marion; Lloyd, Peter; Halabi, Atef

2015-06-01

Serelaxin is a recombinant form of human relaxin-2 in development for treatment of acute heart failure. This study aimed to evaluate the pharmacokinetics (PK) of serelaxin in patients with hepatic impairment. Secondary objectives included evaluation of immunogenicity, safety and tolerability of serelaxin. This was an open-label, parallel group study (NCT01433458) comparing the PK of serelaxin following a single 24 h intravenous (i.v.) infusion (30 μg kg(-1)  day(-1) ) between patients with mild, moderate or severe hepatic impairment (Child-Pugh class A, B, C) and healthy matched controls. Blood sampling and standard safety assessments were conducted. Primary non-compartmental PK parameters [including area under the serum concentration-time curve AUC(0-48 h) and AUC(0-∞) and serum concentration at 24 h post-dose (C24h )] were compared between each hepatic impairment group and healthy controls. A total of 49 subjects (including 25 patients with hepatic impairment) were enrolled, of which 48 subjects completed the study. In all groups, the serum concentration of serelaxin increased over the first few hours of infusion, reached steady-state at 12-24 h and then declined following completion of infusion, with a mean terminal half-life of 7-8 h. All PK parameter estimates were comparable between each group of patients with hepatic impairment and healthy controls. No serious adverse events, discontinuations due to adverse events or deaths were reported. No serelaxin treatment-related antibodies developed during this study. The PK and safety profile of serelaxin were not affected by hepatic impairment. No dose adjustment is needed for serelaxin treatment of 48 h i.v. infusion in patients with hepatic impairment. © 2014 The British Pharmacological Society.

Eficiency of different doses of rituximab in rheumatoid arthritis.

Science.gov (United States)

Mena-Vázquez, Natalia; Manrique-Arija, Sara; Ureña-Garnica, Inmaculada; Romero-Barco, Carmen M; Jiménez-Núñez, Francisco G; Coret, Virginia; Irigoyen-Oyarzábal, María Victoria; Fernández-Nebro, Antonio

2016-01-01

Evaluate the effectiveness, cost and safety of rituximab in patients with rheumatoid arthritis (RA) depending on the dose used. Retrospective observational study conducted on 52 patients with RA treated with at least one dose of rituximab for 135.3 patient-years were included. Three treatment groups were obtained: (G1) First course and following two 1g infusions separated by 15 days; (G2) First course 2 infusions of 1g followed by 2 infusions of 500mg; (G3) First course and followed by 2 infusions of 500mg separated by 15 days. Re-treatments were administered on-demand according to the clinical activity. The retention time (Log-Rank), retreats and adverse events rates (incidence rate ratio) and treatment costs per patient-month of rituximab were analysed by groups. Group 2 showed a better cost-effectiveness ratio than group 1, as it was associated with a longer retention of rituximab (mean [95% CI] 65.7 [60.8 to 70.7] months vs 33.5 [22.7 to 44.3]; P<.001) and a lower rate of severe adverse events with only a slight increase in the rate of retreatment (courses/patient-year [95% CI] 1.66 [1.39 to 1.93] vs. 1.01 [0.69 to 1.34]; P=.005), and in the costs (median/patient-month, €484.89 vs. €473.45). Although group 3 was €41.20/patient-month cheaper than group 2, it was associated with a higher rate of re-treatments and shorter retention of rituximab (P<.001). The use of full-dose rituximab at onset, followed by reduced doses in successive courses administered on-demand retreatment may be the most cost-effective option. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

Lifetime radiation risks from low-dose rate radionuclides in beagles

International Nuclear Information System (INIS)

Goldman, M.; Rosenblatt, L.S.

1985-01-01

One of the largest, long-term (25-yr) animal studies on the effects of low-dose internal irradiation is almost completed. Some 335 beagles were given continuous exposure to graded 90 Sr [low linear energy transfer (LET)] in their diets (D-dogs) through adulthood. A second group (R-dogs) was given fractionated doses of 225 Ra (high LET) as young adults. A third group of 44 was given a single injection of 90 Sr as adults (S-dogs) to compare single to continuous dosages. All dogs were followed through their lifetimes. Only one of the 848 dogs is still alive. The animals were whole-body counted over their entire life span and were examined frequently for assessment of medical status. There were no acute radiation lethalities. Analyses of the large data base from these dogs have begun and preliminary indications are that 90 Sr, which was tested over a 1500-fold skeletal dose rate range, does not cause significant life shortening at average accumulation skeletal doses of ∼2500 rads (25 Gy) and that a curvilinear dose response curve for life shortening was seen at higher accumulation doses. The data will be discussed in terms of modern epidemiological concepts and quantifications will be related to certain parameters of human risk from acute or chronic radiation exposures

Oral sumatriptan for migraine in children and adolescents: a randomized, multicenter, placebo-controlled, parallel group study.

Science.gov (United States)

Fujita, Mitsue; Sato, Katsuaki; Nishioka, Hiroshi; Sakai, Fumihiko

2014-04-01

The objective of this article is to evaluate the efficacy and tolerability of two doses of oral sumatriptan vs placebo in the acute treatment of migraine in children and adolescents. Currently, there is no approved prescription medication in Japan for the treatment of migraine in children and adolescents. This was a multicenter, outpatient, single-attack, double-blind, randomized, placebo-controlled, parallel-group study. Eligible patients were children and adolescents aged 10 to 17 years diagnosed with migraine with or without aura (ICHD-II criteria 1.1 or 1.2) from 17 centers. They were randomized to receive sumatriptan 25 mg, 50 mg or placebo (1:1:2). The primary efficacy endpoint was headache relief by two grades on a five-grade scale at two hours post-dose. A total of 178 patients from 17 centers in Japan were enrolled and randomized to an investigational product in double-blind fashion. Of these, 144 patients self-treated a single migraine attack, and all provided a post-dose efficacy assessment and completed the study. The percentage of patients in the full analysis set (FAS) population who report pain relief at two hours post-treatment for the primary endpoint was higher in the placebo group than in the pooled sumatriptan group (38.6% vs 31.1%, 95% CI: -23.02 to 8.04, P  = 0.345). The percentage of patients in the FAS population who reported pain relief at four hours post-dose was higher in the pooled sumatriptan group (63.5%) than in the placebo group (51.4%) but failed to achieve statistical significance ( P  = 0.142). At four hours post-dose, percentages of patients who were pain free or had complete relief of photophobia or phonophobia were numerically higher in the sumatriptan pooled group compared to placebo. Both doses of oral sumatriptan were well tolerated. No adverse events (AEs) were serious or led to study withdrawal. The most common AEs were somnolence in 6% (two patients) in the sumatriptan 25 mg treatment group and chest

The optimal parameter for radiation dose in pediatric low dose abdominal CT: cross-sectional dimensions versus body weight

International Nuclear Information System (INIS)

Jung, Yoon Young; Goo, Hyun Woo

2008-01-01

To investigate the best parameter between cross-sectional dimensions and body weight in pediatric low dose abdominal CT. One hundred and thirty six children consecutively underwent weight-based abdominal CT. The subjects consisted of group 1 (79 children, weight range 10.0-19.9 kg) and group 2 (57 children, weight range 20.0-39.9 kg). Abdominal cross-sectional dimensions including circumference, area, anteroposterior diameters and transverse diameters were calculated. Image noise (standard deviation of CT density) was measured by placing a region of interest in the posterior segment of the right hepatic lobe on a CT image at the celiac axis. The measured image noise was correlated with the cross-sectional abdominal dimensions and body weight for subjects in each group. In group 1 subjects,area, circumference, transverse diameter, anteroposterior diameter, and body weight showed a significant positive correlation with image noise in descending order(γ = 0.63, 0.62, 0.61, 0.51, and 0.49; ρ < 0.0001). In group 2 subjects, transverse diameter, circumference, area, anteroposterior diameter, and body weight showed a significant positive correlation with image noise in descending order (γ = 0.83, 0.82, 0.78, 0.71, and 0.71; ρ < 0.0001). Cross-sectional dimensions such as area, circumference, and transverse diameter showed a higher positive correlation with image noise than body weight for pediatric low dose abdominal CT

Efficacy and Safety of a Colistin Loading Dose, High-Dose Maintenance Regimen in Critically Ill Patients With Multidrug-Resistant Gram-Negative Pneumonia.

Science.gov (United States)

Elefritz, Jessica L; Bauer, Karri A; Jones, Christian; Mangino, Julie E; Porter, Kyle; Murphy, Claire V

2017-09-01

Emergence of multidrug-resistant (MDR) gram-negative (GN) pathogens and lack of novel antibiotics have increased the use of colistin, despite unknown optimal dosing. This study aimed to evaluate the safety and efficacy of a colistin loading dose, high-dose (LDHD) maintenance regimen in patients with MDR-GN pneumonia. A retrospective cohort analysis was performed comparing critically ill patients with MDR-GN pneumonia pre- and postimplementation of a colistin LDHD guideline with a primary outcome of clinical cure. Safety was assessed using incidence of acute kidney injury (AKI) based on RIFLE (risk, injury, failure, loss, end-stage renal disease) criteria. Seventy-two patients met the inclusion criteria (42 preimplementation and 30 postimplementation). Clinical cure was achieved in 23 (55%) patients in the preimplementation group and 20 (67%) patients in the postimplementation group ( P = .31). AKI occurred in 50% of the patients during the preimplementation period and 58% during the postimplementation period ( P = .59) with no difference in initiation rates of renal replacement therapy. The increased clinical cure rate after implementation of the colistin LDHD guideline did not reach statistical significance. The LDHD guideline, however, was not associated with an increased incidence of AKI, despite higher intravenous colistin doses. Opportunity exists to optimize colistin dosage while balancing toxicity, but larger studies are warranted.

Different dose-dependent effects of ebselen in sciatic nerve ischemia-reperfusion injury in rats.

Science.gov (United States)

Ozyigit, Filiz; Kucuk, Aysegul; Akcer, Sezer; Tosun, Murat; Kocak, Fatma Emel; Kocak, Cengiz; Kocak, Ahmet; Metineren, Hasan; Genc, Osman

2015-08-26

Ebselen is an organoselenium compound which has strong antioxidant and anti-inflammatory effects. We investigated the neuroprotective role of ebselen pretreatment in rats with experimental sciatic nerve ischemia-reperfusion (I/R) injury. Adult male Sprague Dawley rats were divided into four groups (N = 7 in each group). Before sciatic nerve I/R was induced, ebselen was injected intraperitoneally at doses of 15 and 30 mg/kg. After a 2 h ischemia and a 3 h reperfusion period, sciatic nerve tissues were excised. Tissue levels of malondialdehyde (MDA) and nitric oxide (NO), and activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) were measured. Sciatic nerve tissues were also examined histopathologically. The 15 mg/kg dose of ebselen reduced sciatic nerve damage and apoptosis (pebselen. Conversely, the 30 mg/kg dose of ebselen increased sciatic nerve damage, apoptosis, iNOS positive cells (pebselen may cause different effects depending on the dose employed. Ebselen may be protective against sciatic nerve I/R injury via antioxidant and antiapoptotic activities at a 15 mg/kg dose, conversely higher doses may cause detrimental effects.

Efficacy between high and medium doses of glucocorticoid therapy in remission induction of IgG4-related diseases: a preliminary randomized controlled trial.

Science.gov (United States)

Wu, Qingjun; Chang, Jie; Chen, Hua; Chen, Yu; Yang, Hongxian; Fei, Yunyun; Zhang, Panpan; Zeng, Xiaofeng; Zhang, Fengchun; Zhang, Wen

2017-05-01

In order to evaluate the efficacy and safety of high versus medium doses of glucocorticoid therapy in remission induction of immunoglobulin G4-related disease (IgG4-RD), we set up a randomized controlled study. Newly diagnosed IgG4-RD patients were randomly assigned to two groups: high doses of prednisone (0.8-1.0 mg/kg/day) and medium doses (0.5-0.6 mg/kg/day). Patients were assessed at weeks 0, 4, 12 and 24. The primary outcome was the remission rate at week 24. The secondary endpoints included IgG4-RD responder index (IgG4-RD RI), IgG and IgG4 levels. Twenty cases in each group finished the study. At week 24, the total response rates were 95% and 80% in high and medium dose groups, respectively. There was no significant difference between the two groups. IgG4-RD RI reduced from 14.9 to 3.0 in the high dose group, while in the medium dose group it was from 13.1 to 3.2. At week 24, the average level of IgG4 reduced from 1576 to 324 mg/dL and from 1445 to 684 mg/dL in the two groups, respectively. Relapsed patients had higher baseline IgG4-RD RI. There was no severe adverse effect shown in both groups. The effect of remission induction was similar in high and medium glucocorticoid groups. However, patients with more organs involved and higher IgG4-RD RI score at baseline might get more benefit with high dose glucocorticoid for remission induction. © 2017 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.

High versus low dose-rate intracavitary irradiation for adenocarcinoma of the uterine cervix

International Nuclear Information System (INIS)

Kim, Woo Chul; Kim, Gwi Eon; Chung, Eun Ji; Suh, Chang Ok; Hong, Soon Won; Cho, Young Kap; Loh, John Jk

1999-01-01

The incidence of adenocarcinoma of the uterine cervix is low. Traditionally, Low Dose Rate (LDR) brachytherapy has been used as a standard modality in the treatment for patients with carcinoma of the uterine cervix. The purpose of this report is to evaluate the effects of the High Dose Rate (HDR) brachytherapy in the patients with adenocarcinoma of the uterine cervix compared with the LDR. From January 1971 to December 1992, 106 patients of adenocarcinoma of uterine cervix were treated with radiation therapy in the Department of Radiation Oncology, Yonsei University with curative intent. LDR brachytherapy was carried out on 35 patients and 71 patients were treated with HDR brachytherapy. In LDR Group, 8 patients were in stage I, 18 in stage II and 9 in stage III. external radiation therapy was delivered with 10 MV X-ray, daily 2 Gy fractionation, total dose 40-46 Gy (median 48 Gy). And LDR Radium intracavitary irradiation was performed with Henschke applicator, 22-56 Gy to point A (median 43 Gy). In HDR Group, there were 16 patients in stage I, 38 in stage II and 17 in stage III. The total dose of external radiation was 40-61 Gy (median 45 Gy), daily 1.8-2.0 Gy. HDR Co-60 intracavitary irradiation was performed with RALS(Remote Afterloading System), 30-57 Gy (median 39 Gy) to point A, 3 times a week, 3 Gy per fraction. The 5-year overall survival rate in LDR Group was 72.9%, 61.9%, 45.0% in stage I, II, III, respectively and corresponding figures for HDR were 87.1%, 58.3%, 41.2%, respectively (p>0.05). There was no statistical difference in terms of the 5-year overall survival rate between HDR Group and LDR Group in adenocarcinoma of the uterine cervix. There was 11% of late complication rates in LDR Group and 27% in HDR Group. There were no prognostic factors compared HDR with LDR group. The incidence of the late complication rate in HDR Group stage II, III was higher than that in LDR Group (16.7% vs. 31.6% in stage II, 11.1% vs. 35.3% in stage III, p>0

Dose Escalation for Prostate Cancer Using the Three-Dimensional Conformal Dynamic Arc Technique: Analysis of 542 Consecutive Patients

International Nuclear Information System (INIS)

Jereczek-Fossa, Barbara A.; Vavassori, Andrea; Fodor, Cristiana; Santoro, Luigi; Zerini, Dario; Cattani, Federica; Garibaldi, Cristina; Cambria, Raffaella; Fodor, Andrei; Boboc, Genoveva Ionela; Vitolo, Viviana; Ivaldi, Giovanni Battista; Musi, Gennaro; De Cobelli, Ottavio; Orecchia, Roberto

2008-01-01

Purpose: To present the results of dose escalation using three-dimensional conformal dynamic arc radiotherapy (3D-ART) for prostate cancer. Methods and Materials: Five hundred and forty two T1-T3N0M0 prostate cancer patients were treated with 3D-ART. Dose escalation (from 76 Gy/38 fractions to 80 Gy/40 fractions) was introduced in September 2003; 32% of patients received 80 Gy. In 366 patients, androgen deprivation was added to 3D-ART. Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria and Houston definition (nadir + 2) were used for toxicity and biochemical failure evaluation, respectively. Median follow-up was 25 months. Results: Acute toxicity included rectal (G1-2 28.9%; G3 0.5%) and urinary events (G1-2 57.9%; G3-4 2.4%). Late toxicity included rectal (G1-2 15.8%; G3-4 3.1%) and urinary events (G1-2 26.9%; G3-4 1.6%). Two-year failure-free survival and overall survival rates were 94.1% and 97.9%, respectively. Poor prognostic group (GS, iPSA, T), transurethral prostate resection, and dose >76 Gy showed significant association to high risk of progression in multivariate analysis (p = 0.014, p = 0.045, and p 0.04, respectively). The negative effect of dose >76 Gy was not observed (p 0.10), when the analysis was limited to 353 patients treated after September 2003 (when dose escalation was introduced). Higher dose was not associated with higher late toxicity. Conclusions: Three-dimensional-ART is a feasible modality allowing for dose escalation (no increase in toxicity has been observed with higher doses). However, the dose increase from 76 to 80 Gy was not associated with better tumor outcome. Further investigation is warranted for better understanding of the dose effect for prostate cancer

Stability of ferritic steel to higher doses: Survey of reactor pressure vessel steel data and comparison with candidate materials for future nuclear systems

International Nuclear Information System (INIS)

Blagoeva, D.T.; Debarberis, L.; Jong, M.; Pierick, P. ten

2014-01-01

This paper is illustrating the potential of the well-known low alloyed clean steels, extensively used for the current light water Reactor Pressure Vessels (RPV) steels, for a likely use as a structural material also for the new generation nuclear systems. This option would provide, especially for large components, affordable, easily accessible and a technically more convenient solution in terms of manufacturing and joining techniques. A comprehensive comparison between several sets of surveillance and research data available for a number of RPV clean steels for doses up to 1.5 dpa, and up to 12 dpa for 9%Cr steels, is carried out in order to evaluate radiation stability of the currently used RPV clean steels even at higher doses. Based on the numerous data available, positive preliminary conclusions are drawn regarding the eventual use of clean RPV steels for the massive structural components of the new reactor systems. - Highlights: • Common embrittlement trend between RPV and advanced steels till intermediate doses. • For doses >1.5 dpa, damage rate saturation tendency is observed for RPV steels. • RPV steels might be conveniently utilised also outside their foreseen dose range

Effect of a simple dose-escalation schedule on tramadol tolerability : assessment in the clinical setting.

Science.gov (United States)

Tagarro, I; Herrera, J; Barutell, C; Díez, M C; Marín, M; Samper, D; Busquet, C; Rodríguez, M J

2005-01-01

To assess the effect of a very simple dose-escalation schedule on tramadol tolerability in clinical practice. This schedule consists of starting treatment with sustained-release tramadol 50mg twice daily, and escalating the dose around 7 days later to 100mg twice daily. Data from 1925 outpatients with non-malignant chronic pain were collected in this multicentre, prospective, comparative, non-randomised, open, observational study. A total of 1071 patients (55.6%) were included in the dose-escalation group (50mg group) and 854 patients (44.4%) in the control group (sustained-release tramadol 100mg twice daily; 100mg group). The proportion of patients who interrupted tramadol treatment due to the occurrence of adverse reactions was significantly lower in the 50mg group (5.6%) than in the 100mg group (12.6%) [p = 0.001]. In line with this, the proportion of patients who experienced at least one adverse reaction was significantly lower in the 50mg group (18.4%) than in the 100mg group (30.4%) [p = 0.001] and, interestingly, the two most frequently reported adverse reactions, nausea and dizziness, were found with a significantly lower frequency in the 50mg group (p < 0.001). Multivariate analysis showed that the risk of safety-related treatment cessations was 2.3 times higher in the 100mg group than in the 50mg group, and 2.2 times higher in females than in males. The two treatments were equally effective in reducing pain intensity (p = 0.121), measured as a reduction in pain score obtained by means of a visual analogue scale. The instauration of tramadol treatment, starting with sustained-release 50mg capsules twice daily and escalating the dose some days later to 100mg twice daily, was shown to be an effective and easy way to improve tramadol tolerability in clinical practice, whilst maintaining its analgesic efficacy.

Professional exposure of medical workers: radiation levels, radiation risk and personal dose monitoring

International Nuclear Information System (INIS)

Bai Guang

2005-01-01

The application of radiation in the field of medicine is the most active area. Due to the rapid and strong development of intervention radiology at present near 20 years, particularly, the medical workers become a popularize group which most rapid increasing and also receiving the must high of professional exposure dose. Because, inter alias, radiation protection management nag training have not fully follow up, the aware of radioactive protection and appropriate approach have tot fully meet the development and need, the professional exposure dose received by medical workers, especially those being engaged in intervention radiology, are more higher, as well as have not yet fully receiving the complete personal dose monitoring, the medical workers become the population group which should be paid the most attention to. The writer would advice in this paper that all medical workers who being received a professional radiation exposure should pay more attention to the safety and healthy they by is strengthening radiation protection and receiving complete personal dose monitoring. (authors)

Absorbed dose to mice in prolonged irradiation by low-dose rate ionizing radiation

Energy Technology Data Exchange (ETDEWEB)

Shiragai, Akihiro [National Inst. of Radiological Sciences, Chiba (Japan); Saitou, Mikio; Kudo, Iwao [and others

2000-07-01

In this paper, the dose absorbed by mice was evaluated as a preliminary study of the late effects of prolonged continuous irradiation of mice with low-dose rate ionizing radiation. Eight-week-old male and female SPF C3H/HeN mice in three irradiation rooms were exposed to irradiation at 8000, 400, and 20 mGy, respectively, using a {sup 137}Cs {gamma}-source. Nine racks were arranged in a circle approximately 2.5 m from the source in each room, and 10 cages were arranged on the 4 shelves of each rack. Dose distributions, such as in air at the source level, in the three rooms were estimated by using ionization chambers, and the absorbed dose distributions in the room and relative dose distributions in the cages in relation to the distance of the cage center were examined. The mean abdomen doses of the mice measured by TLD were compared with the absorbed doses in the cages. The absorbed dose distributions showed not only inverse-inverse-square-law behavior with distance from the source, but geometric symmetry in every room. The inherent scattering and absorption in each room are responsible for such behavior and asymmetry. Comparison of relative dose distributions revealed cage positions that are not suitable for experiments with high precision doses, but all positions can be used for prolonged continuous irradiation experiments if the position of the cages is rotated regularly. The mean abdomen doses of the mice were similar in each cage. The mean abdomen doses of the mice and the absorbed doses in a cage were almost the same in all cages. Except for errors concerning the positions of the racks and cages, the uncertainties in the exposure doses were estimated to be about {+-}12% for 8000 mGy group, 17% for 400 mGy group, and 35% for 20 mGy group. (K.H.)

Biological effects of low doses of radiation at low dose rate

International Nuclear Information System (INIS)

1996-05-01

The purpose of this report was to examine available scientific data and models relevant to the hypothesis that induction of genetic changes and cancers by low doses of ionizing radiation at low dose rate is a stochastic process with no threshold or apparent threshold. Assessment of the effects of higher doses of radiation is based on a wealth of data from both humans and other organisms. 234 refs., 26 figs., 14 tabs

Evaluation of patient dose during computed tomography angiography

International Nuclear Information System (INIS)

Dafalla, Elamam Yagoob Taha

2015-10-01

Computed tomography (CT), is an x-ray procedure that generates high quality cross sectional images of the body, and by comparison to other radiological diagnosis, CT is responsible for higher doses to patients. The evaluation of patient dose from computed tomography for pulmonary examinations the CT is responsible for higher doses to patients. The radiation dose was measured in three hospitals in Khartoum State during March 2015-October 2015 using different CT modalities. The radiation dose was higher at Alzytouna hospital than Daralelaj hospital and Alatebaa hospital was lowest. In this study, the mean effective dose for first hospital was 23.83±3.93 mSv and the mean effective dose for second hospital was 8.94±1.64 mSv and the mean effective dose for third hospital was 2.96±0.79. (author)

Risk at Low Doses: Scientific knowledge, uncertainties and management

International Nuclear Information System (INIS)

Giusssani, A.; Ballarini, F.; Ottolenghi, A.

2002-01-01

Most of the applications of ionizing radiation in the medical field, for the exposed workers as well as the majority of patients undergoing diagnostic examinations, can be seen as low situations. Epidemiological information is however available for dose and dose rates higher than the values typical of most medical situation. Main source of information is the Life Span Study (LSS) of Japanese. A-bomb survivors, supplemented by studies of selected groups of exposed workers (uranium miners, radium painters) or radiotherapy patients with a detailed follow-up history. All of these group studies, however, suffer from one or more of the following limitations: - lack of adequate dosimetry - lack of a reliable control group for the necessary comparison - influence of concomitant factors (not always easy to find out) - influence of social conditions. In addition exposed study populations are different than the population of patients for which the risk estimates are needed in the medical situation. Recent studies aimed to evaluate the available data on the cohorts of the inhabitants of the Techa river settlements as well as of the workers of the Mayak nuclear facilities may provide in the future useful information on large populations chronically exposed to relatively low doses. (Author)

Individual fluorouracil dose adjustment in FOLFOX based on pharmacokinetic follow-up compared with conventional body-area-surface dosing: a phase II, proof-of-concept study.

Science.gov (United States)

Capitain, Olivier; Asevoaia, Andreaa; Boisdron-Celle, Michele; Poirier, Anne-Lise; Morel, Alain; Gamelin, Erick

2012-12-01

To compare the efficacy and safety of pharmacokinetically (PK) guided fluorouracil (5-FU) dose adjustment vs. standard body-surface-area (BSA) dosing in a FOLFOX (folinic acid, fluorouracil, oxaliplatin) regimen in metastatic colorectal cancer (mCRC). A total of 118 patients with mCRC were administered individually determined PK-adjusted 5-FU in first-line FOLFOX chemotherapy. The comparison arm consisted of 39 patients, and these patients were also treated with FOLFOX with 5-FU by BSA. For the PK-adjusted arm 5-FU was monitored during infusion, and the dose for the next cycle was based on a dose-adjustment chart to achieve a therapeutic area under curve range (5-FU(ODPM Protocol)). The objective response rate was 69.7% in the PK-adjusted arm, and median overall survival and median progression-free survival were 28 and 16 months, respectively. In the traditional patients who received BSA dosage, objective response rate was 46%, and overall survival and progression-free survival were 22 and 10 months, respectively. Grade 3/4 toxicity was 1.7% for diarrhea, 0.8% for mucositis, and 18% for neutropenia in the dose-monitored group; they were 12%, 15%, and 25%, respectively, in the BSA group. Efficacy and tolerability of PK-adjusted FOLFOX dosing was much higher than traditional BSA dosing in agreement with previous reports for 5-FU monotherapy PK-adjusted dosing. Analysis of these results suggests that PK-guided 5-FU therapy offers added value to combination therapy for mCRC. Copyright © 2012 Elsevier Inc. All rights reserved.

Late change of normal tissue treated either by high dose rate or low dose rate interstitial brachytherapy. A retrospective comparative study on oral and oropharyngeal mucosa

International Nuclear Information System (INIS)

Nose, Takayuki; Koizumi, Masahiko; Nishiyama, Kinji; Inoue, Toshihiko

2002-01-01

The purpose of this study was to compare late changes of normal tissue treated either by high dose rate (HDR) or low dose rate (LDR) interstitial brachytherapy. For HDR group, 22 oropharynx cancer patients who were treated by HDR Ir-192 interstitial brachytherapy with/without external beam radiotherapy in Osaka (Osaka Medical Center for Cancer and Cardiovascular Diseases and Osaka University Hospital) during June 1994 through April 2000 and came to the follow-up clinics during July 2000 through December 2000 were studied. For LDR group, 26 oropharynx cancer patients who were treated by LDR Ir-192 interstitial brachytherapy with/without external beam radiotherapy in Nancy (Centre Alexis Vautrin) during February 1989 through July 1998 and came to the follow-up clinics during April 1999 through July 1999 were studied. The standard HDR schedules were 54 Gy/9 fr/5-6 days for monotherapy and 18-24 Gy/3-4 fr/2-3 days following 45 Gy external beam radiotherapy. The standard LDR schedules were 65 Gy/5-6 days for monotherapy and 15-25 Gy/2-3 days following 50 Gy external beam radiotherapy. For evaluation of the late changes, we scored the mucosal and muscular changes inside the treated volume using the modified Dische score system and the RTOG/EORTC late radiation morbidity scoring scheme. For 6 items of the modified Dische score system, no significant difference was found between HDR and LDR groups. For the remaining 2 items (pallor, mobility impairment of faucial pillars), LDR group showed higher scores (p=0.010, 0.002). LDR group showed a trend toward higher scores for the RTOG/EORTC scheme (p=0.059). Some predict late effects by HDR interstitial brachytherapy to be severer than by LDR because no dose-rate effects can be expected. Our study, however, showed at least equivalent or even milder late changes by HDR. Appropriate fractionation schedule and extra geometrical sparing effects by optimized dose distribution of HDR group might result in milder late changes. With our

Brachytherapy for early oral tongue cancer. Low dose rate to high dose rate

International Nuclear Information System (INIS)

Yamazaki, Hideya; Inoue, Takehiro; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Inoue, Toshihiko; Furukawa, Souhei; Kakimoto, Naoya

2003-01-01

To examine the compatibility of low dose rate (LDR) with high dose rate (HDR) brachytherapy, we reviewed 399 patients with early oral tongue cancer (T1-2N0M0) treated solely by brachytherapy at Osaka University Hospital between 1967 and 1999. For patients in the LDR group (n=341), the treatment sources consisted of Ir-192 pin for 227 patients (1973-1996; irradiated dose, 61-85 Gy; median, 70 Gy), Ra-226 needle for 113 patients (1967-1986; 55-93 Gy; median, 70 Gy). Ra-226 and Ir-192 were combined for one patient. Ir-192 HDR (microSelectron-HDR) was used for 58 patients in the HDR group (1991-present; 48-60 Gy; median, 60 Gy). LDR implantations were performed via oral and HDR via a submental/submandibular approach. The dose rates at the reference point for the LDR group were 0.30 to 0.8 Gy/h, and for the HDR group 1.0 to 3.4 Gy/min. The patients in the HDR group received a total dose of 48-60 Gy (8-10 fractions) during one week. Two fractions were administered per day (at least a 6-h interval). The 3- and 5-year local control rates for patients in the LDR group were 85% and 80%, respectively, and those in the HDR group were both 84%. HDR brachytherapy showed the same lymph-node control rate as did LDR brachytherapy (67% at 5 years). HDR brachytherapy achieved the same locoregional result as did LDR brachytherapy. A converting factor of 0.86 is applicable for HDR in the treatment of early oral tongue cancer. (author)

Quadrupling Inhaled Glucocorticoid Dose to Abort Asthma Exacerbations.

Science.gov (United States)

McKeever, Tricia; Mortimer, Kevin; Wilson, Andrew; Walker, Samantha; Brightling, Christopher; Skeggs, Andrew; Pavord, Ian; Price, David; Duley, Lelia; Thomas, Mike; Bradshaw, Lucy; Higgins, Bernard; Haydock, Rebecca; Mitchell, Eleanor; Devereux, Graham; Harrison, Timothy

2018-03-08

Asthma exacerbations are frightening for patients and are occasionally fatal. We tested the concept that a plan for patients to manage their asthma (self-management plan), which included a temporary quadrupling of the dose of inhaled glucocorticoids when asthma control started to deteriorate, would reduce the incidence of severe asthma exacerbations among adults and adolescents with asthma. We conducted a pragmatic, unblinded, randomized trial involving adults and adolescents with asthma who were receiving inhaled glucocorticoids, with or without add-on therapy, and who had had at least one exacerbation in the previous 12 months. We compared a self-management plan that included an increase in the dose of inhaled glucocorticoids by a factor of 4 (quadrupling group) with the same plan without such an increase (non-quadrupling group), over a period of 12 months. The primary outcome was the time to a first severe asthma exacerbation, defined as treatment with systemic glucocorticoids or an unscheduled health care consultation for asthma. A total of 1922 participants underwent randomization, of whom 1871 were included in the primary analysis. The number of participants who had a severe asthma exacerbation in the year after randomization was 420 (45%) in the quadrupling group as compared with 484 (52%) in the non-quadrupling group, with an adjusted hazard ratio for the time to a first severe exacerbation of 0.81 (95% confidence interval, 0.71 to 0.92; P=0.002). The rate of adverse effects, which were related primarily to local effects of inhaled glucocorticoids, was higher in the quadrupling group than in the non-quadrupling group. In this trial involving adults and adolescents with asthma, a personalized self-management plan that included a temporary quadrupling of the dose of inhaled glucocorticoids when asthma control started to deteriorate resulted in fewer severe asthma exacerbations than a plan in which the dose was not increased. (Funded by the Health Technology

CT for evaluation of potential renal donors – How does iterative reconstruction influence image quality and dose?

Energy Technology Data Exchange (ETDEWEB)

Kahn, Johannes, E-mail: johannes.kahn@charite.de [Department of Radiology, Charité, Charitéplatz 1, 10117 Berlin (Germany); Grupp, Ulrich, E-mail: ulrich.grupp@charite.de [Department of Radiology, Charité, Charitéplatz 1, 10117 Berlin (Germany); Rotzinger, Roman, E-mail: roman.rotzinger@charite.de [Department of Radiology, Charité, Charitéplatz 1, 10117 Berlin (Germany); Kaul, David, E-mail: david.kaul@charite.de [Department of Radiooncology and Radiotherapy, Charité, Charitéplatz 1, 10117 Berlin (Germany); Schäfer, Max-Ludwig, E-mail: max-ludwig.schaefer@charite.de [Department of Radiology, Charité, Charitéplatz 1, 10117 Berlin (Germany); Streitparth, Florian, E-mail: florian.streitparth@charite.de [Department of Radiology, Charité, Charitéplatz 1, 10117 Berlin (Germany)

2014-08-15

Purpose: To assess ASIR (adaptive statistical iterative reconstruction) technique regarding dose reduction and its impact on image quality in evaluation CTs of potential kidney donors. Materials and methods: Between May and November 2013, a prospective study of 53 assumingly healthy potential kidney donors was conducted. The subjects underwent abdominal evaluation CT prior to the planned explantation of a kidney and were randomly divided into 2 groups: Group A was examined with an ASIR 40 protocol (n = 26), group B (n = 27) was examined using a standard FBP (filtered back projection) protocol. Image quality was assessed both quantitatively (by obtaining attenuation values in different organ regions and calculating SNR and CNRs) and qualitatively (by two observers who evaluated image quality using a 5-point scale system). Applied dose was analyzed as CTDIvol (mGy), total DLP (mGy × cm) and effective dose (mSv). Results: Applied dose in group A was about 26% lower than in group B (p < 0.05). Between both groups, dose determining parameters such as scan length and patients’ body diameter showed no significant difference. SNR (signal-to-noise ratio) was significantly higher in group A (p < 0.05). CNRs (contrast-to-noise ratios) for different tissues were not significantly different. Observer rated image quality showed no significant difference. Conclusion: ASIR can contribute to a relevant dose reduction without any loss of image quality in CT scans for evaluating potential kidney donors.

Optimal dose and volume for postoperative radiotherapy in brain oligometastases from lung cancer: a retrospective study

Energy Technology Data Exchange (ETDEWEB)

Chung, Seung Yeun; Kim, Hye Ryun; Cho, Byoung Chul; Lee, Chang Geol; Suh, Chang Ok [Yonsei Cancer Center, Yonsei University College of Medicine, Seoul (Korea, Republic of); Chang, Jong Hee [Dept. of Neurosurgery, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

2017-06-15

To evaluate intracranial control after surgical resection according to the adjuvant treatment received in order to assess the optimal radiotherapy (RT) dose and volume. Between 2003 and 2015, a total of 53 patients with brain oligometastases from non-small cell lung cancer (NSCLC) underwent metastasectomy. The patients were divided into three groups according to the adjuvant treatment received: whole brain radiotherapy (WBRT) ± boost (WBRT ± boost group, n = 26), local RT/Gamma Knife surgery (local RT group, n = 14), and the observation group (n = 13). The most commonly used dose schedule was WBRT (25 Gy in 10 fractions, equivalent dose in 2 Gy fractions [EQD2] 26.04 Gy) with tumor bed boost (15 Gy in 5 fractions, EQD2 16.25 Gy). The WBRT ± boost group showed the lowest 1-year intracranial recurrence rate of 30.4%, followed by the local RT and observation groups, at 66.7%, and 76.9%, respectively (p = 0.006). In the WBRT ± boost group, there was no significant increase in the 1-year new site recurrence rate of patients receiving a lower dose of WBRT (EQD2) <27 Gy compared to that in patients receiving a higher WBRT dose (p = 0.553). The 1-year initial tumor site recurrence rate was lower in patients receiving tumor bed dose (EQD2) of ≥42.3 Gy compared to those receiving <42.3 Gy, although the difference was not significant (p = 0.347). Adding WBRT after resection of brain oligometastases from NSCLC seems to enhance intracranial control. Furthermore, combining lower-dose WBRT with a tumor bed boost may be an attractive option.

Dose-dependent transitions in mechanisms of toxicity: case studies

International Nuclear Information System (INIS)

Slikker, William; Andersen, Melvin E.; Bogdanffy, Matthew S.; Bus, James S.; Cohen, Steven D.; Conolly, Rory B.; David, Raymond M.; Doerrer, Nancy G.; Dorman, David C.; Gaylor, David W.; Hattis, Dale; Rogers, John M.; Setzer, R. Woodrow; Swenberg, James A.; Wallace, Kendall

2004-01-01

Experience with dose response and mechanisms of toxicity has shown that multiple mechanisms may exist for a single agent along the continuum of the full dose-response curve. It is highly likely that critical, limiting steps in any given mechanistic pathway may become overwhelmed with increasing exposures, signaling the emergence of new modalities of toxic tissue injury at these higher doses. Therefore, dose-dependent transitions in principal mechanisms of toxicity may occur, and could have significant impact on the interpretation of reference data sets for risk assessment. To illustrate the existence of dose-dependent transitions in mechanisms of toxicity, a group of academic, government, and industry scientists, formed under the leadership of the ILSI Health and Environmental Sciences Institute (HESI), developed a series of case studies. These case studies included acetaminophen, butadiene, ethylene glycol, formaldehyde, manganese, methylene chloride, peroxisome proliferator-activated receptor (PPAR), progesterone/hydroxyflutamide, propylene oxide, vinyl acetate, vinyl chloride, vinylidene chloride, and zinc. The case studies formed the basis for technical discourse at two scientific workshops in 2003

Evaluation of effective dose from CT scans for overweight and obese adult patients using the VirtualDose software

International Nuclear Information System (INIS)

Liang, Baohui; Gao, Yiming; Chen, Zhi; Xu, X. George

2017-01-01

This paper evaluates effective dose (ED) of overweight and obese patients who undergo body computed tomography (CT) examinations. ED calculations were based on tissue weight factors in the International Commission on Radiological Protection Publication 103 (ICRP 103). ED per unit dose length product (DLP) are reported as a function of the tube voltage, body mass index (BMI) of patient. The VirtualDose software was used to calculate ED for male and female obese phantoms representing normal weight, overweight, obese 1, obese 2 and obese 3 patients. Five anatomic regions (chest, abdomen, pelvis, abdomen/pelvis and chest/abdomen/pelvis) were investigated for each phantom. The conversion factors were computed from the DLP, and then compared with data previously reported by other groups. It was observed that tube voltage and BMI are the major factors that influence conversion factors of obese patients, and that ED computed using ICRP 103 tissue weight factors were 24% higher for a CT chest examination and 21% lower for a CT pelvis examination than the ED using ICRP 60 factors. For body CT scans, increasing the tube voltage from 80 to 140 kVp would increase the conversion factors by as much as 19-54% depending on the patient's BMI. Conversion factor of female patients was ∼7% higher than the factors of male patients. DLP and conversion factors were used to estimate ED, where conversion factors depended on tube voltage, sex, BMI and tissue weight factors. With increasing number of obese individuals, using size-dependence conversion factors will improve accuracy, in estimating patient radiation dose. (authors)

Estimation of thyroid equivalent doses during evacuation based on body surface contamination levels in the nuclear accident of FDNPS in 2011

Science.gov (United States)

Ohba, Takashi; Hasegawa, Arifumi; Kohayakawa, Yoshitaka; Kondo, Hisayoshi; Suzuki, Gen

2017-09-01

To reduce uncertainty in thyroid dose estimation, residents' radiation protection behavior should be reflected in the estimation. Screening data of body surface contamination provide information on exposure levels during evacuation. Our purpose is to estimate thyroid equivalent doses based on body surface contamination levels using a new methodology. We obtained a record of 7,539 residents/evacuees. Geiger-Mueller survey meter measurement value in cpm was translated into Bq/cm2 according to the nuclides densities obtained by measuring clothing from two persons by germanium γ-spectrometer. The measurement value of body surface contamination on head was adjusted by a natural removal rate of 15 hours and radionuclides' physical half-life. Thyroid equivalent dose of 1-year-old children by inhalation was estimated by two-dimensional Monte Carlo simulation. The proportions of evacuees/residents with measurement value in cpm of Namie and Minamisoma groups were higher than those of other groups during both periods (p<0.01, Kruskal-Wallis). During 12-14 March period, 50 and 95 percentiles of thyroid equivalent doses by inhalation were estimated as 2.7 and 86.0 mSv, respectively, for Namie group, and 4.2 and 17.2 mSv, respectively, for Minamisoma group, 0.1 and 1.0 mSv, respectively, for Tomioka/Okuma/Futaba/Naraha group, and 0.2 and 2.1 mSv, respectively, for the other group. During 15- 17 March period, 50 and 95 percentiles of thyroid equivalent doses by inhalation were 0.8 and 15.7 mSv, respectively, for Namie group, and 1.6 and 8.4 mSv, respectively, for Minamisoma group, 0.2 and 13.2 mSv, respectively, for Tomioka/Okuma/Futaba/Naraha group, and 1.2 and 12.7 mSv, respectively, for the other group. It was indicated that inhalation dose was generally higher in Namie and Minamisoma groups during 12-14 March than those during 15-17 March might reflect different self-protective behavior to radioactive plumes from other groups.

Periodical assessment of genitourinary and gastrointestinal toxicity in patients who underwent prostate low-dose-rate brachytherapy

International Nuclear Information System (INIS)

Tanaka, Nobumichi; Asakawa, Isao; Anai, Satoshi; Hirayama, Akihide; Hasegawa, Masatoshi; Konishi, Noboru; Fujimoto, Kiyohide

2013-01-01

To compare the periodical incidence rates of genitourinary (GU) and gastrointestinal (GI) toxicity in patients who underwent prostate low-dose-rate brachytherapy between the monotherapy group (seed implantation alone) and the boost group (in combination with external beam radiation therapy (EBRT)). A total of 218 patients with a median follow-up of 42.5 months were enrolled. The patients were divided into 2 groups by treatment modality, namely, the monotherapy group (155 patients) and the boost group (63 patients). The periodical incidence rates of GU and GI toxicity were separately evaluated and compared between the monotherapy group and the boost group using the National Cancer Institute - Common Terminology Criteria for Adverse Events, version 3.0. To elucidate an independent factor among clinical and postdosimetric parameters to predict grade 2 or higher GU and GI toxicity in the acute and late phases, univariate and multivariate logistic regression analyses were carried out. Of all patients, 78.0% showed acute GU toxicity, and 7.8% showed acute GI toxicity, while 63.8% showed late GU toxicity, and 21.1% showed late GI toxicity. The incidence rates of late GU and GI toxicity were significantly higher in the boost group. Multivariate analysis showed that the International Prostate Symptom Score (IPSS) before seed implantation was a significant parameter to predict acute GU toxicity, while there were no significant predictive parameters for acute GI toxicity. On the other hand, combination with EBRT was a significant predictive parameter for late GU toxicity, and rectal volume (mL) receiving 100% of the prescribed dose (R100) was a significant predictive parameter for late GI toxicity. The boost group showed higher incidence rates of both GU and GI toxicity. Higher IPSS before seed implantation, combination with EBRT and a higher R100 were significant predictors for acute GU, late GU and late GI toxicity

Dose-dependent efficacy of the Vitex agnus castus extract Ze 440 in patients suffering from premenstrual syndrome.

Science.gov (United States)

Schellenberg, Ruediger; Zimmermann, Christian; Drewe, Jürgen; Hoexter, Godehard; Zahner, Catherine

2012-11-15

Preparations of Vitex agnus castus L. (VAC) have been shown to be effective to treat irregular menstrual cycles, cyclical mastalgia and symptoms of the premenstrual syndrome (PMS). However, the dose-effect relationship for the treatment of PMS has not yet been established. This study aimed to investigate the clinical effects of three different doses of the VAC extract Ze 440 in comparison to placebo in patients suffering from PMS. In a multicenter, double-blind, placebo-controlled, parallel-group study, 162 female patients with PMS (18-45 years) were randomized to either placebo or different doses of Ze 440 (8, 20 and 30 mg) over three menstrual cycles. PMS symptoms' severity was assessed by patients using visual analog scales (VAS) for the symptoms irritability, mood alteration, anger, headache, bloating and breast fullness. Each of the treatments was well tolerated. Improvement in the total symptom score (TSS) in the 20mg group was significantly higher than in the placebo and 8 mg treatment group. The higher dose of 30 mg, on the other hand, did not significantly decrease symptom severity compared to the 20mg treatment, providing a rational for the usage of 20mg. Corresponding results were observed with the single PMS symptom scores. This study demonstrated that the VAC extract Ze 440 was effective in relieving symptoms of PMS, when applied in a dose of 20mg. Therefore, for patients suffering from PMS, 20mg Ze 440 should be the preferred daily dose. Copyright © 2012 Elsevier GmbH. All rights reserved.

Effects of adaptive statistical iterative reconstruction on radiation dose reduction and diagnostic accuracy of pediatric abdominal CT

Energy Technology Data Exchange (ETDEWEB)

Bae, Sohi; Kim, Myung-Joon; Lee, Mi-Jung [Yonsei University College of Medicine, Department of Radiology and Research Institute of Radiological Science, Severance Children' s Hospital, Seoul (Korea, Republic of); Yoon, Choon-Sik [Yonsei University College of Medicine, Department of Radiology, Gangnam Severance Hospital, Seoul (Korea, Republic of); Kim, Dong Wook; Hong, Jung Hwa [Yonsei University College of Medicine, Biostatistics Collaboration Unit, Seoul (Korea, Republic of)

2014-12-15

Since children are more radio-sensitive than adults, there is a need to minimize radiation exposure during CT exams. To evaluate the effects of adaptive statistical iterative reconstruction (ASIR) on radiation dose reduction, image quality and diagnostic accuracy in pediatric abdominal CT. We retrospectively reviewed the abdominal CT examinations of 41 children (24 boys and 17 girls; mean age: 10 years) with a low-dose radiation protocol and reconstructed with ASIR (the ASIR group). We also reviewed routine-dose abdominal CT examinations of 41 age- and sex-matched controls reconstructed with filtered-back projection (control group). Image quality was assessed objectively as noise measured in the liver, spleen and aorta, as well as subjectively by three pediatric radiologists for diagnostic acceptability using a four-point scale. Radiation dose and objective image qualities of each group were compared with the paired t-test. Diagnostic accuracy was evaluated by reviewing follow-up imaging studies and medical records in 2012 and 2013. There was 46.3% dose reduction of size-specific dose estimates in ASIR group (from 13.4 to 7.2 mGy) compared with the control group. Objective noise was higher in the liver, spleen and aorta of the ASIR group (P < 0.001). However, the subjective image quality was average or superior in 84-100% of studies. Only one image was subjectively rated as unacceptable by one reviewer. There was only one case with interpretational error in the control group and none in the ASIR group. Use of the ASIR technique resulted in greater than a 45% reduction in radiation dose without impairing subjective image quality or diagnostic accuracy in pediatric abdominal CT, despite increased objective image noise. (orig.)

Effects of adaptive statistical iterative reconstruction on radiation dose reduction and diagnostic accuracy of pediatric abdominal CT

International Nuclear Information System (INIS)

Bae, Sohi; Kim, Myung-Joon; Lee, Mi-Jung; Yoon, Choon-Sik; Kim, Dong Wook; Hong, Jung Hwa

2014-01-01

Since children are more radio-sensitive than adults, there is a need to minimize radiation exposure during CT exams. To evaluate the effects of adaptive statistical iterative reconstruction (ASIR) on radiation dose reduction, image quality and diagnostic accuracy in pediatric abdominal CT. We retrospectively reviewed the abdominal CT examinations of 41 children (24 boys and 17 girls; mean age: 10 years) with a low-dose radiation protocol and reconstructed with ASIR (the ASIR group). We also reviewed routine-dose abdominal CT examinations of 41 age- and sex-matched controls reconstructed with filtered-back projection (control group). Image quality was assessed objectively as noise measured in the liver, spleen and aorta, as well as subjectively by three pediatric radiologists for diagnostic acceptability using a four-point scale. Radiation dose and objective image qualities of each group were compared with the paired t-test. Diagnostic accuracy was evaluated by reviewing follow-up imaging studies and medical records in 2012 and 2013. There was 46.3% dose reduction of size-specific dose estimates in ASIR group (from 13.4 to 7.2 mGy) compared with the control group. Objective noise was higher in the liver, spleen and aorta of the ASIR group (P < 0.001). However, the subjective image quality was average or superior in 84-100% of studies. Only one image was subjectively rated as unacceptable by one reviewer. There was only one case with interpretational error in the control group and none in the ASIR group. Use of the ASIR technique resulted in greater than a 45% reduction in radiation dose without impairing subjective image quality or diagnostic accuracy in pediatric abdominal CT, despite increased objective image noise. (orig.)

Evaluating higher doses of Shunthi - Guduchi formulations for safety in treatment of osteoarthritis knees: A Government of India NMITLI arthritis project

OpenAIRE

Arvind Chopra; Manjit Saluja; Girish Tillu; Anuradha Venugopalan; Gumdal Narsimulu; Sanjeev Sarmukaddam; Bhushan Patwardhan

2012-01-01

Background: Results of an exploratory trial suggested activity trends of Zingiber officinale-Tinopsora cordifolia (platform combination)-based formulations in the treatment of Osteoarthritis (OA) Knees. These formulations were "platform combination+Withania somnifera+Tribulus terrestris0" (formulation B) and "platform combination+Emblica officinale" (formulation C). This paper reports safety of these formulations when used in higher doses (1.5-2 times) along with Sallaki Guggul and Bhallataka...

Modern Radiation Therapy for Hodgkin Lymphoma: Field and Dose Guidelines From the International Lymphoma Radiation Oncology Group (ILROG)

International Nuclear Information System (INIS)

Specht, Lena; Yahalom, Joachim; Illidge, Tim; Berthelsen, Anne Kiil; Constine, Louis S.; Eich, Hans Theodor; Girinsky, Theodore; Hoppe, Richard T.; Mauch, Peter; Mikhaeel, N. George; Ng, Andrea

2014-01-01

Radiation therapy (RT) is the most effective single modality for local control of Hodgkin lymphoma (HL) and an important component of therapy for many patients. These guidelines have been developed to address the use of RT in HL in the modern era of combined modality treatment. The role of reduced volumes and doses is addressed, integrating modern imaging with 3-dimensional (3D) planning and advanced techniques of treatment delivery. The previously applied extended field (EF) and original involved field (IF) techniques, which treated larger volumes based on nodal stations, have now been replaced by the use of limited volumes, based solely on detectable nodal (and extranodal extension) involvement at presentation, using contrast-enhanced computed tomography, positron emission tomography/computed tomography, magnetic resonance imaging, or a combination of these techniques. The International Commission on Radiation Units and Measurements concepts of gross tumor volume, clinical target volume, internal target volume, and planning target volume are used for defining the targeted volumes. Newer treatment techniques, including intensity modulated radiation therapy, breath-hold, image guided radiation therapy, and 4-dimensional imaging, should be implemented when their use is expected to decrease significantly the risk for normal tissue damage while still achieving the primary goal of local tumor control. The highly conformal involved node radiation therapy (INRT), recently introduced for patients for whom optimal imaging is available, is explained. A new concept, involved site radiation therapy (ISRT), is introduced as the standard conformal therapy for the scenario, commonly encountered, wherein optimal imaging is not available. There is increasing evidence that RT doses used in the past are higher than necessary for disease control in this era of combined modality therapy. The use of INRT and of lower doses in early-stage HL is supported by available data. Although the

Land Use and Food Intake of Future Inhabitants: Outlining a Representative Individual of the Most Exposed Group for Dose Assessment

International Nuclear Information System (INIS)

Saetre, Peter; Kautsky, Ulrik; Valentin, Jack; Lageraas, Per; Avila, Rodolfo

2013-01-01

The radiation doses to humans resulting from a potential release of radionuclides from a geological repository for long-lived waste are assessed over tens or even hundreds of thousands of years. Ingestion is expected to be the major exposure pathway, and the group with the highest exposures will be those that consume the most contaminated food. In this paper, we characterize the group of individuals with the highest exposures by considering the physical and biological characteristics of the contaminated area and human requirements for energy and nutrients. We then calculate intake rates based on land-use scenarios drawn from self-sustained communities spanning prehistoric times to an industrial-age agrarian culture. The approach is illustrated by simulating groundwater release of four radionuclides to an expected discharge area. We argue that the derived intake rates may serve as credible bounding cases when projected doses are evaluated for compliance with regulatory criteria

Optimized dose distribution of a high dose rate vaginal cylinder

International Nuclear Information System (INIS)

Li Zuofeng; Liu, Chihray; Palta, Jatinder R.

1998-01-01

Purpose: To present a comparison of optimized dose distributions for a set of high-dose-rate (HDR) vaginal cylinders calculated by a commercial treatment-planning system with benchmark calculations using Monte-Carlo-calculated dosimetry data. Methods and Materials: Optimized dose distributions using both an isotropic and an anisotropic dose calculation model were obtained for a set of HDR vaginal cylinders. Mathematical optimization techniques available in the computer treatment-planning system were used to calculate dwell times and positions. These dose distributions were compared with benchmark calculations with TG43 formalism and using Monte-Carlo-calculated data. The same dwell times and positions were used for a quantitative comparison of dose calculated with three dose models. Results: The isotropic dose calculation model can result in discrepancies as high as 50%. The anisotropic dose calculation model compared better with benchmark calculations. The differences were more significant at the apex of the vaginal cylinder, which is typically used as the prescription point. Conclusion: Dose calculation models available in a computer treatment-planning system must be evaluated carefully to ensure their correct application. It should also be noted that when optimized dose distribution at a distance from the cylinder surface is calculated using an accurate dose calculation model, the vaginal mucosa dose becomes significantly higher, and therefore should be carefully monitored

The impact of the oxygen scavenger on the dose-rate dependence and dose sensitivity of MAGIC type polymer gels

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Khan, Muzafar; Heilemann, Gerd; Kuess, Peter; Georg, Dietmar; Berg, Andreas

2018-03-01

Recent developments in radiation therapy aimed at more precise dose delivery along with higher dose gradients (dose painting) and more efficient dose delivery with higher dose rates e.g. flattening filter free (FFF) irradiation. Magnetic-resonance-imaging based polymer gel dosimetry offers 3D information for precise dose delivery techniques. Many of the proposed polymer gels have been reported to exhibit a dose response, measured as relaxation rate ΔR2(D), which is dose rate dependent. A lack of or a reduced dose-rate sensitivity is very important for dosimetric accuracy, especially with regard to the increasing clinical use of FFF irradiation protocols with LINACs at high dose rates. Some commonly used polymer gels are based on Methacrylic-Acid-Gel-Initiated-by-Copper (MAGIC). Here, we report on the dose sensitivity (ΔR2/ΔD) of MAGIC-type gels with different oxygen scavenger concentration for their specific dependence on the applied dose rate in order to improve the dosimetric performance, especially for high dose rates. A preclinical x-ray machine (‘Yxlon’, E  =  200 kV) was used for irradiation to cover a range of dose rates from low \\dot{D} min  =  0.6 Gy min-1 to high \\dot{D} max  =  18 Gy min-1. The dose response was evaluated using R2-imaging of the gel on a human high-field (7T) MR-scanner. The results indicate that all of the investigated dose rates had an impact on the dose response in polymer gel dosimeters, being strongest in the high dose region and less effective for low dose levels. The absolute dose rate dependence \\frac{(Δ R2/Δ D)}{Δ \\dot{D}} of the dose response in MAGIC-type gel is significantly reduced using higher concentrations of oxygen scavenger at the expense of reduced dose sensitivity. For quantitative dose evaluations the relative dose rate dependence of a polymer gel, normalized to its sensitivity is important. Based on this normalized sensitivity the dose rate sensitivity was reduced distinctly

THE IMPACT OF HEPARIN IMPLEMENTER (GAG IN THE RABBIT INSEMINATION DOSE

Directory of Open Access Journals (Sweden)

Martin Fik

2013-10-01

Full Text Available The aim of this work was to evaluate the impact of implementer heparin in insemination dose in rabbits selected on reproductive parameters.The experiment was monitored reproductive parameters (conceptual relationship, the number of live-born pups per litter, the number of dead-born pups per litter, the number of live-born pups per inseminated does 156 does in the experimental group and 165 does in the control group. We used the ejaculate of synthetic broiler rabbit population with concentration of sperm 25-50 mil. / 0.5 ml / 1 ID. Heparin was added at a dose - 0.06 ml = 10 mg per 0.5 ml semen / 1 ID. Assessing selected reproductive parameters in does inseminated with insemination dose with the addition of heparin, we observed a higher conceptual proportion of 14.12 % in the experimental group compared to the control group. These differences did not show a statistically significant difference (χ 2 3.56-. The number of live-born pups per litter was 8.69 ± 4.10 pc in the experimental group and 8.41 ± 3.62 pc in the control group (P> 0.05. The number of dead-born pups was recorded 0.74 pc in the experimental group and 0.76 pc in the control group (P> 0.05. The number of live-born pups per litter per inseminated does we have seen improvement in favor of experimental group by 1.39 pc. This parameter was within each of experiments ranged from 0.91 to 1.66 pc live-born pups to inseminated does.

Ability Grouping's Effects on Grades and the Attainment of Higher Education: A Natural Experiment

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Bygren, Magnus

2016-01-01

To test the effect of ability grouping on grades and the attainment of higher education, this study examines a naturally occurring experiment--an admission reform that dramatically increased ability sorting between schools in the municipality of Stockholm. Following six cohorts of students (N = 79,020) from the age of 16 to 26, I find a mean…

The effect of weight-based chemotherapy dosing in a cohort of gynecologic oncology patients.

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Hansen, Jean; Stephan, Jean-Marie; Freesmeier, Michele; Bender, David; Button, Anna; Goodheart, Michael J

2015-07-01

Many clinicians limit chemotherapy doses based on a maximum body surface area (BSA) of 2m(2). We sought to determine how chemotherapy-related toxicities compared between groups of patients that varied with respect to BSA. We hypothesized that obese patients receiving weight-based (WB) dosing would not have significantly higher chemotherapy-related toxicities than control groups. We performed a retrospective review of patients with BSA≥2m(2) who received WB chemotherapy for a gynecologic cancer between January and August 2013. Subjects were matched with two controls: patients with BSAGynecologic cancer patients with BSA≥2m(2) treated with WB chemotherapy had no increase in hematologic or non-hematologic toxicities when compared to controls. Consideration should be given to using WB dosing in obese patients with gynecologic malignancies. Further investigation is required to determine the effect of WB dosing on progression-free and overall survival in obese gynecologic cancer patients. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparing Patient Satisfaction and Intubating Conditions Using Succinylcholine or Low-Dose Rocuronium for Rigid Bronchoscopy: A Randomized Study.

Science.gov (United States)

Ghezel-Ahmadi, Verena; Ghezel-Ahmadi, David; Mangen, Jacques; Bolukbas, Servet; Welker, Andreas; Kuerschner, Veit Christian; Fischer, Andreas; Schirren, Joachim; Beck, Grietje

2015-09-01

Despite its serious side effects, succinylcholine is commonly used for neuromuscular relaxation in short procedures, such as rigid bronchoscopy and tracheobronchial interventions. The application of low-dose rocuronium reversed by low-dose sugammadex might be a modern alternative. The aim of this study was to compare patient satisfaction, incidence of postoperative myalgia (POM) as well as intubating conditions of these two muscle relaxants for rigid bronchoscopy. A single-center, prospective-randomized, blinded study of 95 patients, scheduled for rigid bronchoscopy and tracheobronchial intervention was conducted. The patients were anesthetized with propofol, remifentanil and either low-dose succinylcholine (S) (0.5 mg/kg) or low-dose rocuronium (0.25 mg/kg) with sugammadex (RS) (0.5 mg/kg). All patients were evaluated on the first and second postinterventional day for their satisfaction with the treatment (rigid bronchoscopy) using a Numeric Analog Rating Scale (NAS 0-10) and the presence and severity of POM (NAS 1-4). Intubating conditions were assessed as excellent, good, or poor on the basis of position of vocal cords and reaction to insertion of the rigid bronchoscope. Patients in the S group were less satisfied with the treatment than patients in RS group (72.7 vs. 93.7%, p = 0.007). The incidence of POM on the first day after intervention was significantly higher in the S group then in the RS group (56.9% vs. 4.3%, p rocuronium in 75% of patients. The anesthetic drug costs were significantly higher in the RS group then in the S group (p rocuronium provided better patient satisfaction and less POM. But with the use of low-dose succinylcholine, the intubating conditions are more comfortable, and it is less expensive than rocuronium/sugammadex. Georg Thieme Verlag KG Stuttgart · New York.

Repeat dose of gonadotropin-releasing hormone agonist trigger in polycystic ovarian syndrome undergoing In Vitro fertilization cycles provides a better cycle outcome - a proof-of-concept study

Directory of Open Access Journals (Sweden)

Krishna Deepika

2017-01-01

Full Text Available Objective: Is a single dose of gonadotropin-releasing hormone agonist (GnRHa trigger to induce final oocyte maturation in polycystic ovarian syndrome (PCOS undergoing in vitro fertilization (IVF cycles with GnRH antagonist protocol sufficient to provide optimal oocyte maturity? Design: This is a prospective, randomized, double-blind, proof-of-concept study. Setting: This study was carried out at a tertiary care center. Material and Methods: A total of 125 patients diagnosed with PCOS defined as per the ESHRE/ASRM Rotterdam criteria (2003 undergoing IVF in antagonist protocol were randomized into two groups. Group A: single dose of GnRHa 0.2 mg, 35 h prior to oocyte retrieval, and Group B: 0.2 mg GnRHa 35 h prior to oocyte retrieval + repeat dose of 0.1 mg 12 h following the 1st dose. 12 h post-trigger, luteinizing hormone (LH, progesterone (P4, and follicle-stimulating hormone (FSH values were estimated. Statistical Analysis: Continuous variables were expressed as mean ± standard deviation and categorical variables as proportions where applicable. Independent sample t-test was used for continuous variables which were normally distributed and Mann–Whitney U-test for data not normally distributed. Chi-square test or Fisher's exact test was used for categorical variables where appropriate. Odds ratio (OR with 95% confidence intervals (CIs was calculated. In addition, receiver operating characteristic curve was used to evaluate the post-trigger LH, P4, and FSH values at 12 h as predictors of oocyte maturity. Main Outcome Measures: Primary outcome: maturity rate of the oocytes. Secondary outcomes: oocyte yield, fertilization rate, availability of good quality embryos on day 3, blastocyst conversion, OHSS rates, post-trigger serum LH (IU/L, FSH (IU/L, and P4 (ng/mL levels implantation rate and clinical pregnancy rate. Results: A higher number of mature (metaphase II oocytes were obtained in Group B compared to Group A (OR of 0.47; CI: 0.38–0

Is it worth to calculate the dose of radioiodine?

International Nuclear Information System (INIS)

Mikalauskas, V.; Kuprionis, G.; Vajauskas, D.

2005-01-01

performed using SPSS for Windows, version 12.0. A p-value less than 0.05 was considered statistically significant. The mean effective half-life for thyroid gland in all patient groups was 5.32 days and there was no significant difference between the groups. Patients with Graves' disease and multinodular toxic goiter in group I (n=42) received a target dose of 124.87±15 Gy, in group II (n=77) - 128.35±10 Gy, in group III (n=153) - 124.29±22 Gy. But, the patients in group IV (n=29) received a target dose of only 103.74±35 Gy, because the administered activity of 131I for outpatients is limited to 400 MBq according to the Lithuanian regulations. In subgroup of patients with toxic adenoma an activity was calculated to deliver 140 and 160 Gy for the treatment in group I (n=72) and in group II accordingly. Received target dose in this subset of patients was in group I 156.19±20 Gy and in group II (n=38) - 158.19±22 Gy. Administration of a single dose of RAI resulted in the control of hyperthyroidism in 91.8% of patients. Unfortunately 35 (8.2%) patients with Graves' disease required the second and two of them the third RAI treatment to achieve either a hypothyroid or a euthyroid state. The second target dose was significantly higher (p<0.05) than the first (128±25 Gy vs 119.8±24 Gy) because was adjusted to the significantly reduced (p<0.05) after the first treatment thyroid volume (40±18 ml vs 18.4±11 ml) and was given for persistent hyperthyroidism after a mean of 13 months minimum 3 months, maximum 34 months). Not sufficient first target dose was delivered to the thyroid due to Lithuanian regulations as mentioned before. The third treatment of 120 and 142 Gy was given in four and nine months in two cases. We concluded that therapeutic success was associated with calculation of individual target dose adjusted to the thyroid uptake, volume and the cause of hyperthyroidism in each patient. (author)

Dose-response analysis of testosterone replacement therapy in patients with female to male gender identity disorder.

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Nakamura, Aya; Watanabe, Masami; Sugimoto, Morito; Sako, Tomoko; Mahmood, Sabina; Kaku, Haruki; Nasu, Yasutomo; Ishii, Kazushi; Nagai, Atsushi; Kumon, Hiromi

2013-01-01

Gender identity disorder (GID) is a conflict between a person's actual physical gender and the one they identify him or herself with. Testosterone is the key agent in the medical treatment of female to male GID patients. We conducted a dose-response analysis of testosterone replacement therapy (TRT) in 138 patients to determine the onset of the therapeutic effects. The TRT consisted of intramuscular injection of testosterone enanthate and patients were divided into three groups; 250 mg every two weeks, 250 mg every three weeks and 125 mg every two weeks. The onset of deepening of voice, increase in facial hair and cessation of menses was evaluated in each group. At one month after the start of TRT, the onset of these physical changes was more prevalent in the group receiving the higher dose of testosterone, and there were dose-dependent effects observed between the three treatment groups. On the other hand, at six months after the start of TRT, most of the patients had achieved treatment responses and there were no dose-dependent effects with regard to the percentage of patients with therapeutic effects. No significant side effects were observed in any of the treatment groups. We demonstrated that the early onset of the treatment effects of TRT is dose-dependent, but within six months of starting TRT, all three doses were highly effective. Current study provides useful information to determine the initial dose of TRT and to suggest possible changes that should be made in the continuous dosage for long term TRT.

Biological impact of high-dose and dose-rate radiation exposure

International Nuclear Information System (INIS)

Maliev, V.; Popov, D.; Jones, J.; Gonda, S.; Prasad, K.; Viliam, C.; Haase, G.; Kirchin, V.; Rachael, C.

2006-01-01

Experimental anti-radiation vaccine is a power tool of immune - prophylaxis of the acute radiation disease. Existing principles of treatment of the acute radiation dis ease are based on a correction of developing patho-physiological and biochemical processes within the first days after irradiation. Protection from radiation is built on the general principles of immunology and has two main forms - active and passive immunization. Active immunization by the essential radiation toxins of specific radiation determinant (S.D.R.) group allows significantly reduce the lethality and increase duration of life among animals that are irradiated by lethal and sub-lethal doses of gamma radiation.The radiation toxins of S.D.R. group have antigenic properties that are specific for different forms of acute radiation disease. Development of the specific and active immune reaction after intramuscular injection of radiation toxins allows optimize a manifestation of a clinical picture and stabilize laboratory parameters of the acute radiation syndromes. Passive immunization by the anti-radiation serum or preparations of immune-globulins gives a manifestation of the radioprotection effects immediately after this kind of preparation are injected into organisms of mammals. Providing passive immunization by preparations of anti-radiations immune-globulins is possible in different periods of time after radiation. Providing active immunization by preparations of S.D.R. group is possible only to achieve a prophylaxis goal and form the protection effects that start to work in 18 - 35 days after an injection of biological active S.D.R. substance has been administrated. However active and passive immunizations by essential anti-radiation toxins and preparations of gamma-globulins extracted from a hyper-immune serum of a horse have significantly different medical prescriptions for application and depend on many factors like a type of radiation, a power of radiation, absorption doses, a time of

Biological impact of high-dose and dose-rate radiation exposure

Energy Technology Data Exchange (ETDEWEB)

Maliev, V.; Popov, D. [Russian Academy of Science, Vladicaucas (Russian Federation); Jones, J.; Gonda, S. [NASA -Johnson Space Center, Houston (United States); Prasad, K.; Viliam, C.; Haase, G. [Antioxida nt Research Institute, Premier Micronutrient Corporation, Novato (United States); Kirchin, V. [Moscow State Veterinary and Biotechnology Acade my, Moscow (Russian Federation); Rachael, C. [University Space Research Association, Colorado (United States)

2006-07-01

Experimental anti-radiation vaccine is a power tool of immune - prophylaxis of the acute radiation disease. Existing principles of treatment of the acute radiation dis ease are based on a correction of developing patho-physiological and biochemical processes within the first days after irradiation. Protection from radiation is built on the general principles of immunology and has two main forms - active and passive immunization. Active immunization by the essential radiation toxins of specific radiation determinant (S.D.R.) group allows significantly reduce the lethality and increase duration of life among animals that are irradiated by lethal and sub-lethal doses of gamma radiation.The radiation toxins of S.D.R. group have antigenic properties that are specific for different forms of acute radiation disease. Development of the specific and active immune reaction after intramuscular injection of radiation toxins allows optimize a manifestation of a clinical picture and stabilize laboratory parameters of the acute radiation syndromes. Passive immunization by the anti-radiation serum or preparations of immune-globulins gives a manifestation of the radioprotection effects immediately after this kind of preparation are injected into organisms of mammals. Providing passive immunization by preparations of anti-radiations immune-globulins is possible in different periods of time after radiation. Providing active immunization by preparations of S.D.R. group is possible only to achieve a prophylaxis goal and form the protection effects that start to work in 18 - 35 days after an injection of biological active S.D.R. substance has been administrated. However active and passive immunizations by essential anti-radiation toxins and preparations of gamma-globulins extracted from a hyper-immune serum of a horse have significantly different medical prescriptions for application and depend on many factors like a type of radiation, a power of radiation, absorption doses, a time of

Ultra-low-dose lung screening CT with model-based iterative reconstruction: an assessment of image quality and lesion conspicuity.

Science.gov (United States)

Ju, Yun Hye; Lee, Geewon; Lee, Ji Won; Hong, Seung Baek; Suh, Young Ju; Jeong, Yeon Joo

2018-05-01

Background Reducing radiation dose inevitably increases image noise, and thus, it is important in low-dose computed tomography (CT) to maintain image quality and lesion detection performance. Purpose To assess image quality and lesion conspicuity of ultra-low-dose CT with model-based iterative reconstruction (MBIR) and to determine a suitable protocol for lung screening CT. Material and Methods A total of 120 heavy smokers underwent lung screening CT and were randomly and equally assigned to one of five groups: group 1 = 120 kVp, 25 mAs, with FBP reconstruction; group 2 = 120 kVp, 10 mAs, with MBIR; group 3 = 100 kVp, 15 mAs, with MBIR; group 4 = 100 kVp, 10 mAs, with MBIR; and group 5 = 100 kVp, 5 mAs, with MBIR. Two radiologists evaluated intergroup differences with respect to radiation dose, image noise, image quality, and lesion conspicuity using the Kruskal-Wallis test and the Chi-square test. Results Effective doses were 61-87% lower in groups 2-5 than in group 1. Image noises in groups 1 and 5 were significantly higher than in the other groups ( P image quality was best in group 1, but diagnostic acceptability of overall image qualities in groups 1-3 was not significantly different (all P values > 0.05). Lesion conspicuities were similar in groups 1-4, but were significantly poorer in group 5. Conclusion Lung screening CT with MBIR obtained at 100 kVp and 15 mAs enables a ∼60% reduction in radiation dose versus low-dose CT, while maintaining image quality and lesion conspicuity.

Low dose versus high dose anti-snake venom therapy in the treatment of haematotoxic snake bite in South India.

Science.gov (United States)

Joseph, Imanto M; Kuriakose, Cijoy K; Dev, Anand Vimal; Philip, George A

2017-10-01

Most of the studies on the appropriate dose of anti-snake venom (ASV) are from tertiary hospitals and the guidelines are unclear. Our observational study compared the outcomes of two prevalent treatment regimes for haematotoxic snake bite in a secondary care hospital in South India. The time to normalisation of whole blood clotting time, mortality and complications were not different between the groups. The average dose of ASV required in the low and high dose groups were 106 mL and 246 mL, respectively. Consequently, patients who received low dose ASV incurred approximately 50% less expense. Urticarial rashes were also significantly fewer in the low dose group.

Improvement of image quality and radiation dose of CT perfusion of the brain by means of low-tube voltage (70 KV)

International Nuclear Information System (INIS)

Li, Zhen-lin; Zhang, Kai; Li, Wang-jiang; Chen, Xian; Wu, Bin; Song, Bin; Li, Hang

2014-01-01

To investigate the feasibility of 70 kV cerebral CT perfusion by comparing image quality and radiation exposure to 80 kV. Thirty patients with suspected cerebral ischemia who underwent dual-source CT perfusion were divided into group A (80 kV, 150 mAs) and group B (70 kV, 150 mAs). Quantitative comparisons were used for maximum enhancement, signal-to-noise index (SNI), and values of cerebral blood flow (CBF), cerebral blood flow (CBV), mean transit time (MTT) on CBF, CBV, and MTT images, and radiation dose from these two groups. Qualitative perfusion images were assessed by two readers. Maximum enhancement for group B was higher than group A (P < 0.05). There were no significant differences between the two groups for SNI on CBF and CBV maps (P = 0.06 - 0.576), but significant differences for MTT when SNI was measured on frontal white matter and temporo-occipital white matter (P < 0.05). There were no differences among values of CBF, CBV, and MTT for both groups (P = 0.251-0.917). Mean image quality score in group B was higher than group A for CBF (P < 0.05), but no differences for CBV (P = 0.542) and MTT (P = 0.962). Radiation dose for group B decreased compared with group A. 70 kV cerebral CT perfusion reduces radiation dose without compromising image quality. (orig.)

Improvement of image quality and radiation dose of CT perfusion of the brain by means of low-tube voltage (70 KV)

Energy Technology Data Exchange (ETDEWEB)

Li, Zhen-lin; Zhang, Kai; Li, Wang-jiang; Chen, Xian; Wu, Bin; Song, Bin [West China Hospital of Sichuan University, Department of Radiology, Chengdu, Sichuan (China); Li, Hang [Sichuan Provincial People' s Hospital, Department of Radiology, Chengdu, Sichuan (China)

2014-08-15

To investigate the feasibility of 70 kV cerebral CT perfusion by comparing image quality and radiation exposure to 80 kV. Thirty patients with suspected cerebral ischemia who underwent dual-source CT perfusion were divided into group A (80 kV, 150 mAs) and group B (70 kV, 150 mAs). Quantitative comparisons were used for maximum enhancement, signal-to-noise index (SNI), and values of cerebral blood flow (CBF), cerebral blood flow (CBV), mean transit time (MTT) on CBF, CBV, and MTT images, and radiation dose from these two groups. Qualitative perfusion images were assessed by two readers. Maximum enhancement for group B was higher than group A (P < 0.05). There were no significant differences between the two groups for SNI on CBF and CBV maps (P = 0.06 - 0.576), but significant differences for MTT when SNI was measured on frontal white matter and temporo-occipital white matter (P < 0.05). There were no differences among values of CBF, CBV, and MTT for both groups (P = 0.251-0.917). Mean image quality score in group B was higher than group A for CBF (P < 0.05), but no differences for CBV (P = 0.542) and MTT (P = 0.962). Radiation dose for group B decreased compared with group A. 70 kV cerebral CT perfusion reduces radiation dose without compromising image quality. (orig.)

Evaluation of radioiodine therapy with fixed doses of 10 and 15 mCi in patients with Graves disease; Avaliacao da radioiodoterapia com doses fixas de 10 e 15 mCi em pacientes com doenca de Graves

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Canadas, Viviane; Vilar, Lucio; Moura, Eliane; Brito, Ana; Castellar, Enio [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Hospital das Clinicas. Servico de Endocrinologia]. E-mail: vivi2207@ig.com.br

2007-10-15

The treatment options for the hyperthyroidism of Graves' disease are antithyroid drugs, surgery and radioiodine, none of which is considered ideal, as they do not act directly on the etiopathogenesis of the disease. Radioiodine has been increasingly used as the treatment of choice because it is a safe and definitive therapy whose administration is very easy. Some authors prefer to administer higher doses in order to deliberately induce hypothyroidism, while others recommend lower doses that result in a lower incidence of hypothyroidism and a greater incidence of euthyroidism. There is no consensus for the optimal regimen of fixed doses to be used and this is the main focus of the present study, where doses of 10 and 15 mCi of {sup 131}I were compared. Among the 164 patients analyzed, 61 (37.2%) were submitted to 10 mCi and 103 (62.8%) to 15 mCi. In the longitudinal analysis it was observed that remission of the hyperthyroidism was statistically different in the sixth month (p < 0.001), being higher in the group that used the dose of 15 mCi, but similar in both groups at 12 and 24 months. It may be concluded that the administration of fixed doses of 10 and 15 mCi of {sup 131}I brought about a similar remission of the hyperthyroidism after 12 months of treatment. Moreover, the remission rate of the hyperthyroidism had no association with age, sex or previous therapy with antithyroid drugs. (author)

Geometrical Sparing Factors for the Rectum and Bladder in the Prediction of Grade 2 and Higher Complications After High-Dose-Rate Brachytherapy for Cervical Cancer

International Nuclear Information System (INIS)

Chen, S.-W.; Liang, J.-A.; Hung, Y.-C.; Yeh, L.-S.; Chang, W.-C.; Yang, S.-N.; Lin, F.-J.

2009-01-01

Purpose: This study aimed to assess the predictive values of geometrical sparing factors for the rectum and bladder in high-dose-rate intracavitary brachytherapy (HDRICB) for Grade 2 and higher late sequelae in patients with cervical cancer. Methods: A total of 392 patients were enrolled in this study. They were treated with external beam radiotherapy to the pelvis, after which HDRICB was performed using Ir-192 remote after-loading at 1-week intervals for three or four sessions. The geometrical sparing factor (GSF) was defined as the average of the ratios between the reference doses and the Point A dose. Results: A total of 46 patients (11.7%) had Grade 2 or higher late rectal complications (36 Grade 2, 9 Grade 3, and 1 Grade 4). In all, 32 patients (8.2%) had Grade 2 or higher late bladder complications (14 Grade 2, 16 Grade 3, and 2 Grade 4). Multivariate analysis demonstrated a high risk of rectal sequelae in patients who developed bladder complications (p = 0.0004, hazard ratio 3.54) and had a rectal GSF greater than 0.7 (p = 0.01, hazard ratio 1.99). The high risk factors for bladder complications were development of rectal complications (p = 0.0004, hazard ratio 3.74), concurrent chemotherapy (p = 0.0001, relative risk 3.94), and a bladder GSF greater than 0.9 (p = 0.01, hazard ratio, 2.53). Conclusion: This study demonstrates the predictive value of GSFs in HDRICB for cervical cancer. Patients with rectal GSFs greater than 0.7 or bladder GSFs greater than 0.9 are at risk for Grade 2 and higher late sequelae.

Geometrical sparing factors for the rectum and bladder in the prediction of grade 2 and higher complications after high-dose-rate brachytherapy for cervical cancer.

Science.gov (United States)

Chen, Shang-Wen; Liang, Ji-An; Hung, Yao-Ching; Yeh, Lian-Shung; Chang, Wei-Chun; Yang, Shih-Neng; Lin, Fang-Jen

2009-12-01

This study aimed to assess the predictive values of geometrical sparing factors for the rectum and bladder in high-dose-rate intracavitary brachytherapy (HDRICB) for Grade 2 and higher late sequelae in patients with cervical cancer. A total of 392 patients were enrolled in this study. They were treated with external beam radiotherapy to the pelvis, after which HDRICB was performed using Ir-192 remote after-loading at 1-week intervals for three or four sessions. The geometrical sparing factor (GSF) was defined as the average of the ratios between the reference doses and the Point A dose. A total of 46 patients (11.7%) had Grade 2 or higher late rectal complications (36 Grade 2, 9 Grade 3, and 1 Grade 4). In all, 32 patients (8.2%) had Grade 2 or higher late bladder complications (14 Grade 2, 16 Grade 3, and 2 Grade 4). Multivariate analysis demonstrated a high risk of rectal sequelae in patients who developed bladder complications (p = 0.0004, hazard ratio 3.54) and had a rectal GSF greater than 0.7 (p = 0.01, hazard ratio 1.99). The high risk factors for bladder complications were development of rectal complications (p = 0.0004, hazard ratio 3.74), concurrent chemotherapy (p = 0.0001, relative risk 3.94), and a bladder GSF greater than 0.9 (p = 0.01, hazard ratio, 2.53). This study demonstrates the predictive value of GSFs in HDRICB for cervical cancer. Patients with rectal GSFs greater than 0.7 or bladder GSFs greater than 0.9 are at risk for Grade 2 and higher late sequelae.

Performances of low-dose dual-energy CT in reducing artifacts from implanted metallic orthopedic devices

Energy Technology Data Exchange (ETDEWEB)

Filograna, Laura [Catholic University of Rome, School of Medicine, University Hospital ' ' A. Gemelli' ' , Department of Radiological Sciences, Institute of Radiology, Rome (Italy); University of Zurich, Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, Zurich (Switzerland); Magarelli, Nicola; Leone, Antonio; Bonomo, Lorenzo [Catholic University of Rome, School of Medicine, University Hospital ' ' A. Gemelli' ' , Department of Radiological Sciences, Institute of Radiology, Rome (Italy); De Waure, Chiara; Calabro, Giovanna Elisa [Catholic University of Rome, School of Medicine, University Hospital ' ' A. Gemelli' ' , Research Centre for Health Technology Assessment, Department of Public Health, Section of Hygiene, Rome (Italy); Finkenstaedt, Tim [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland); Thali, Michael John [University of Zurich, Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, Zurich (Switzerland)

2016-07-15

The objective was to evaluate the performances of dose-reduced dual-energy computed tomography (DECT) in decreasing metallic artifacts from orthopedic devices compared with dose-neutral DECT, dose-neutral single-energy computed tomography (SECT), and dose-reduced SECT. Thirty implants in 20 consecutive cadavers underwent both SECT and DECT at three fixed CT dose indexes (CTDI): 20.0, 10.0, and 5.0 mGy. Extrapolated monoenergetic DECT images at 64, 69, 88, 105, 120, and 130 keV, and individually adjusted monoenergy for optimized image quality (OPTkeV) were generated. In each group, the image quality of the seven monoenergetic images and of the SECT image was assessed qualitatively and quantitatively by visually rating and by measuring the maximum streak artifact respectively. The comparison between SECT and OPTkeV evaluated overall within all groups showed a significant difference (p <0.001), with OPTkeV images providing better images. Comparing OPTkeV with the other DECT images, a significant difference was shown (p <0.001), with OPTkeV and 130-keV images providing the qualitatively best results. The OPTkeV images of 5.0-mGy acquisitions provided percentages of images with scores 1 and 2 of 36 % and 30 % respectively, compared with 0 % and 33.3 % of the corresponding SECT images of 10- and 20-mGy acquisitions. Moreover, DECT reconstructions at the OPTkeV of the low-dose group showed higher CT numbers than the SECT images of dose groups 1 and 2. This study demonstrates that low-dose DECT permits a reduction of artifacts due to metallic implants to be obtained in a similar manner to neutral-dose DECT and better than reduced or neutral-dose SECT. (orig.)

Radiation dose and image quality in pediatric chest CT: effects of iterative reconstruction in normal weight and overweight children

International Nuclear Information System (INIS)

Yoon, Haesung; Kim, Myung-Joon; Shin, Hyun Joo; Kim, Hyun Gi; Lee, Mi-Jung; Yoon, Choon-Sik; Choi, Jiin

2015-01-01

New CT reconstruction techniques may help reduce the burden of ionizing radiation. To quantify radiation dose reduction when performing pediatric chest CT using a low-dose protocol and 50% adaptive statistical iterative reconstruction (ASIR) compared with age/gender-matched chest CT using a conventional dose protocol and reconstructed with filtered back projection (control group) and to determine its effect on image quality in normal weight and overweight children. We retrospectively reviewed 40 pediatric chest CT (M:F = 21:19; range: 0.1-17 years) in both groups. Radiation dose was compared between the two groups using paired Student's t-test. Image quality including noise, sharpness, artifacts and diagnostic acceptability was subjectively assessed by three pediatric radiologists using a four-point scale (superior, average, suboptimal, unacceptable). Eight children in the ASIR group and seven in the control group were overweight. All radiation dose parameters were significantly lower in the ASIR group (P < 0.01) with a greater than 57% dose reduction in overweight children. Image noise was higher in the ASIR group in both normal weight and overweight children. Only one scan in the ASIR group (1/40, 2.5%) was rated as diagnostically suboptimal and there was no unacceptable study. In both normal weight and overweight children, the ASIR technique is associated with a greater than 57% mean dose reduction, without significantly impacting diagnostic image quality in pediatric chest CT examinations. However, CT scans in overweight children may have a greater noise level, even when using the ASIR technique. (orig.)

Radiation dose and image quality in pediatric chest CT: effects of iterative reconstruction in normal weight and overweight children

Energy Technology Data Exchange (ETDEWEB)

Yoon, Haesung; Kim, Myung-Joon; Shin, Hyun Joo; Kim, Hyun Gi; Lee, Mi-Jung [Yonsei University College of Medicine, Department of Radiology and Research Institute of Radiological Science, Severance Children' s Hospital, Seoul (Korea, Republic of); Yoon, Choon-Sik [Yonsei University College of Medicine, Department of Radiology, Gangnam Severance Hospital, Seoul (Korea, Republic of); Choi, Jiin [Yonsei University College of Medicine, Biostatistics Collaboration Unit, Seoul (Korea, Republic of)

2015-03-01

New CT reconstruction techniques may help reduce the burden of ionizing radiation. To quantify radiation dose reduction when performing pediatric chest CT using a low-dose protocol and 50% adaptive statistical iterative reconstruction (ASIR) compared with age/gender-matched chest CT using a conventional dose protocol and reconstructed with filtered back projection (control group) and to determine its effect on image quality in normal weight and overweight children. We retrospectively reviewed 40 pediatric chest CT (M:F = 21:19; range: 0.1-17 years) in both groups. Radiation dose was compared between the two groups using paired Student's t-test. Image quality including noise, sharpness, artifacts and diagnostic acceptability was subjectively assessed by three pediatric radiologists using a four-point scale (superior, average, suboptimal, unacceptable). Eight children in the ASIR group and seven in the control group were overweight. All radiation dose parameters were significantly lower in the ASIR group (P < 0.01) with a greater than 57% dose reduction in overweight children. Image noise was higher in the ASIR group in both normal weight and overweight children. Only one scan in the ASIR group (1/40, 2.5%) was rated as diagnostically suboptimal and there was no unacceptable study. In both normal weight and overweight children, the ASIR technique is associated with a greater than 57% mean dose reduction, without significantly impacting diagnostic image quality in pediatric chest CT examinations. However, CT scans in overweight children may have a greater noise level, even when using the ASIR technique. (orig.)

Optimizing a single fixed dose of Iodine-131 in Graves' Disease (An Experience)

International Nuclear Information System (INIS)

Khan, S.H.

2007-01-01

Full text: Kashmir is a Himalayan mountain state of India enclosed by high snow capped ridges of Pir Panjal Mountains at an average height of 4000-5000 meters above the sea level. For most of the 4 million inhabitants in this land locked valley, agriculture horticulture and handcrafts are the main source of income. Due to long and severe winters the terraced farming on the mountain slopes yield just a single crop of rice which is barely sufficient to meet the local needs of this staple diet. People are relatively poor with low annual per capita income. Goiter is endemic in the Valley of Kashmir. In a published report the overall prevalence of goiter among the school going children in Kashmir between the ages of 5 years is 45.2% (+ SEM) with urinary iodine excretion of 49 + 3.55 μg per gram of creatinine. The extremely shy people of Kashmir are casual towards the aesthetic aspects of their goiters but nevertheless seek medical advice when associated with physical symptoms. In a published study of 203 patients of thyrotoxicosis from Kashmir, Graves' disease was the commonest cause, accounting for 63% of patients. One hundred and twentyone patients of Graves' disease were prospectively studied for their response to a single fixed dose of I-131. Patients were randomly treated with two different fixed doses of I- 131. Sixty four patients belonging to Group-I received a fixed dose of 185 MBq (Low Dose) and 57 patients belonging to Group -2 received 370 MBq (High Dose) of I- 131. Following therapy all patients were evaluated at 3 months. Patients with normal or reduced thyroid hormone levels were termed as responders and those with persistently elevated levels of thyroid hormone were termed as non responders. The response rates among the two groups were analyzed for their statistical significance. Patients treated with the high fixed dose of 370 MBq revealed good response to therapy achieving a rate of 91.22%, while the response rate in the group of patients treated with

Lopinavir/ritonavir dosing during pregnancy in Brazil and maternal/infant laboratory abnormalities

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Mario Ferreira Peixoto

Full Text Available OBJECTIVES: To describe laboratory abnormalities among HIV-infected women and their infants with standard and increased lopinavir/ritonavir (LPV/r dosing during the third trimester of pregnancy. METHODS: We evaluated data on pregnant women from NISDI cohorts (2002-2009 enrolled in Brazil, who received at least 28 days of LPV/r during the third pregnancy trimester and gave birth to singleton infants. RESULTS: 164 women received LPV/r standard dosing [(798/198 or 800/200 mg/day (Group 1] and 70 increased dosing [(> 800/200 mg/day (Group 2]. Group 1 was more likely to have advanced clinical disease and to use ARVs for treatment, and less likely to have CD4 counts > 500 cells/mm³. Mean plasma viral load was higher in Group 2. There were statistically significant, but not clinically meaningful, differences between groups in mean AST, ALT, cholesterol, and triglycerides. The proportion of women with Grade 3 or 4 adverse events was very low, with no statistically significant differences between groups in severe adverse events related to ALT, AST, total bilirubin, cholesterol, or triglycerides. There were statistically significant, but not clinically meaningful, differences between infant groups in ALT and creatinine. The proportion of infants with Grade 3 or 4 adverse events was very low, and there were no statistically significant differences in severe adverse events related to ALT, AST, BUN, or creatinine. CONCLUSION: The proportions of women and infants with severe laboratory adverse events were very low. Increased LPV/r dosing during the third trimester of pregnancy appears to be safe for HIV-infected women and their infants.

Nuclear medicine external individual occupational doses in Rio de Janeiro

International Nuclear Information System (INIS)

Mauricio, Claudia L.P.; Lima, Ana Luiza S.; Silva, Herica L.R. da; Santos, Denison Souza; Silva, Claudio Ribeiro da

2009-01-01

According to the Brazilian National Database there are about 300 Nuclear Medicine Services (NMS) in Brazil, 44 of them located in the State of Rio de Janeiro (RJ). Individual dose measurements are an important input for the evaluation of occupational exposure in order to demonstrate the effectiveness of radioprotection implementation and to keep individual doses as low as possible. In Brazil, most nuclear medicine (NM) staff is routinely monitored for external dose. The internal committed dose is estimated only in abnormal conditions. This paper makes a statistics analysis of all the RJ NMS annual external occupational doses in year 2005. A study of the evolution of monthly external individual doses higher than 4.00 mSv from 2004 to 2008 is also presented. The number of registered thorax monthly dose higher than 4.0 mSv is increasing, as its value. In this period the highest dose measured reaches 56.9 mSv, in one month, in 2008. About 50% of the annual doses are smaller than the monthly record level of 0.20 mSv. In 2005, around 100 professionals of RJ NMS received annual doses higher than 4.0 mSv, considering only external doses, but no one receives doses higher than 20.0 mSv. Extremities dosimeters are used by about 15% of the staff. In some cases, these doses are more than 10 times higher than the dose in thorax. This study shows the importance to improve radiation protection procedures in NM. (author)

Fucoidan cytotoxicity against human breast cancer T47D cell line increases with higher level of sulfate ester group

Science.gov (United States)

Saepudin, Endang; Alfita Qosthalani, Fildzah; Sinurat, Ellya

2018-01-01

The anticancer activity of different sulfate ester group content in different molecular weight was examined. The anticancer activity was achieved in vitro on human breast cancer T47D cell line. Fucoidan with lower molecular weight (5.79 kDa) tends to have lower sulfate ester group content (8.69%) and resulted in higher IC50 value (184.22 μg/mL). While fucoidan with higher molecular weight (785.12 kDa) tends to have higher sulfate level (18.63%) and achieved lower IC50 value (75.69 μg/mL). The result showed that in order to maintain fucoidan cytotoxic activity against human breast cancer T47D cell line, the sulfate content should be remain high. Keywords: fucoidan, sulfate ester group, human breast cancer

Dose conversion factors of radiation doses at normal operation discharges. E. Description of geographical surroundings and critical group; Dosomraekningsfaktorer foer normaldriftutslaepp. E. Omraadesbeskrivningar och kritisk grupp

Energy Technology Data Exchange (ETDEWEB)

Hallberg, Bengt

2001-10-01

A study was performed in order to develop and supplement existing models for calculating radiation doses from discharges of radionuclides under normal operating conditions at the Swedish NPPs at Barsebaeck, Forsmark, Oskarshamn and Ringhals, and at the nuclear plants at Studsvik and the Westinghouse Atom fuel plant. A general description of the surroundings of each plant is given in this report, together with an inventory of agricultural activities, forestry, areas for leisure activities etc. The conditions of the critical group has been selected based on the description of the surroundings and the modeling of dispersion in the atmosphere and fallout on the ground. In contrast to earlier models where fictive critical groups were used, the present model is based on factual circumstances.

The usefulness of metal markers for CTV-based dose prescription in high-dose-rate interstitial brachytherapy

International Nuclear Information System (INIS)

Yoshida, Ken; Mitomo, Masanori; Nose, Takayuki; Koizumi, Masahiko; Nishiyama, Kinji; Yoshida, Mineo

2002-01-01

We employ a clinical target volume (CTV)-based dose prescription for high-dose-rate (HDR) interstitial brachytherapy. However, it is not easy to define CTV and organs at risk (OAR) from X-ray film or CT scanning. To solve this problem, we have utilized metal markers since October 1999. Moreover, metal markers can help modify dose prescription. By regulating the doses to the metal markers, refining the dose prescription can easily be achieved. In this research, we investigated the usefulness of the metal markers. Between October 1999 and May 2001, 51 patients were implanted with metal markers at Osaka Medical Center for Cancer and Cardiovascular Diseases (OMCC), Osaka National Hospital (ONH) and Sanda City Hospital (SCH). Forty-nine patients (head and neck: 32; pelvis: 11; soft tissue: 3; breast: 3) using metal markers were analyzed. During operation, we implanted 179 metal markers (49 patients) to CTV and 151 markers (26 patients) to OAR. At treatment planning, CTV was reconstructed judging from the metal markers, applicator position and operation records. Generally, we prescribed the tumoricidal dose to an isodose surface that covers CTV. We also planned to limit the doses to OAR lower than certain levels. The maximum normal tissue doses were decided 80%, 150%, 100%, 50% and 200% of the prescribed doses for the rectum, the urethra, the mandible, the skin and the large vessel, respectively. The doses to the metal markers using CTV-based dose prescription were generated. These were compared with the doses theoretically calculated with the Paris system. Treatment results were also investigated. The doses to the 158 metal markers (42 patients) for CTV were higher than ''tumoricidal dose''. In 7 patients, as a result of compromised dose prescription, 9 markers were lower than the tumoricidal dose. The other 12 markers (7%) were excluded from dose evaluation because they were judged as miss-implanted. The doses to the 142 metal markers (24 patients) for OAR were lower

High-Dose Chloroquine for Treatment of Chloroquine-Resistant Plasmodium falciparum Malaria

DEFF Research Database (Denmark)

Ursing, Johan; Rombo, Lars; Bergqvist, Yngve

2016-01-01

BACKGROUND:  Due to development of multidrug-resistant Plasmodium falciparum new antimalarial therapies are needed. In Guinea-Bissau, routinely used triple standard-dose chloroquine remained effective for decades despite the existence of "chloroquine-resistant" P. falciparum. This study aimed...... to determine the in vivo efficacy of higher chloroquine concentrations against P. falciparum with resistance-conferring genotypes. METHODS:  Standard or double-dose chloroquine was given to 892 children aged ...-up. The P. falciparum resistance-conferring genotype (pfcrt 76T) and day 7 chloroquine concentrations were determined. Data were divided into age groups (chloroquine is prescribed according to body weight. RESULTS:  Adequate clinical...

Low dose coronary CT angiography with 256-slice helical CT

International Nuclear Information System (INIS)

Zhang Xiaodong; Tang Binghang; Li Fangyun

2011-01-01

of 573) in B, 96.1% (548 of 570) in C, and 85.7% (505/589) in D, with no significant difference for A vs C (Z= -1.351, P>0.05) and with significant differences for B vs D (Z=-2.236, P<0.05). Linear correlation analysis indicated a significant degradation of image quality with the increase of heart rate using SAS mode (Spearman correlation, r=0.577, P<0.01). ROC analysis established an upper HR threshold of 78 bpm for obtaining diagnostic image quality using SAS mode (AUC = 0.827, P<0.05). The average radiation dose in group A [(2.6±0.5) mSv] reduced 75% comparing with that in group C [(10.6±2.3) mSv], and the average radiation dose in group B [(4.0±0.7) mSv] reduced 69% comparing with that in group D [(13.0±1.4) mSv]. Conclusion: Using SAS mode to perform low-dose CCTA with 256-slice helical CT could keep the image quality and reduce radiation dose significantly. Our preliminary experience suggests a good promise of this technique which could be applied to a wider group of patients such as with higher heart rates. (authors)

Analysis of workers' dose records from the Greek Dose Registry Information System

International Nuclear Information System (INIS)

Kamenopoulou, V.; Dimitriou, P.; Proukakis, Ch.

1995-01-01

The object of this work is the study of the individual film badge annual dose information of classified workers in Greece, monitored and assessed by the central dosimetry service of the Greek Atomic Energy Commission. Dose summaries were recorded and processed by the Dose Registry Information System. The statistical analysis refers to the years 1989-93 and deals with the distribution of individuals in the occupational groups, the mean annual dose, the collective dose, the distribution of the dose over the different specialties and the number of workers that have exceeded any of the established dose limits. Results concerning the annual dose summaries, demonstrate a year-by-year reduction in the mean individual dose to workers in the health sector. Conversely, exposures in the industrial sector did not show any decreasing tendency during the period under consideration. (Author)

Equivalent dose determination in foraminifera: analytical description of the CO2--signal dose-response curve

International Nuclear Information System (INIS)

Hoffmann, D.; Woda, C.; Mangini, A.

2003-01-01

The dose-response of the CO 2 - signal (g=2.0006) in foraminifera with ages between 19 and 300 ka is investigated. The sum of two exponential saturation functions is an adequate function to describe the dose-response curve up to an additional dose of 8000 Gy. It yields excellent dating results but requires an artificial doses of at least 5000 Gy. For small additional doses of about 500 Gy the single exponential saturation function can be used to calculate a reliable equivalent dose D E , although it does not describ the dose-response for higher doses. The CO 2 - -signal dose-response indicates that the signal has two components of which one is less stable than the other

Dose Response of MARV/Angola Infection in Cynomolgus Macaques following IM or Aerosol Exposure

Science.gov (United States)

Johnston, Sara C.; Lin, Kenny L.; Twenhafel, Nancy A.; Raymond, Jo Lynne W.; Shamblin, Joshua D.; Wollen, Suzanne E.; Wlazlowski, Carly B.; Wilkinson, Eric R.; Botto, Miriam A.; Goff, Arthur J.

2015-01-01

Marburg virus infection in humans causes a hemorrhagic disease with a high case fatality rate. Countermeasure development requires the use of well-characterized animal models that mimic human disease. To further characterize the cynomolgus macaque model of MARV/Angola, two independent dose response studies were performed using the intramuscular or aerosol routes of exposure. All animals succumbed at the lowest target dose; therefore, a dose effect could not be determined. For intramuscular-exposed animals, 100 PFU was the first target dose that was not significantly different than higher target doses in terms of time to disposition, clinical pathology, and histopathology. Although a significant difference was not observed between aerosol-exposed animals in the 10 PFU and 100 PFU target dose groups, 100 PFU was determined to be the lowest target dose that could be consistently obtained and accurately titrated in aerosol studies. PMID:26413900

Dose Response of MARV/Angola Infection in Cynomolgus Macaques following IM or Aerosol Exposure.

Directory of Open Access Journals (Sweden)

Sara C Johnston

Full Text Available Marburg virus infection in humans causes a hemorrhagic disease with a high case fatality rate. Countermeasure development requires the use of well-characterized animal models that mimic human disease. To further characterize the cynomolgus macaque model of MARV/Angola, two independent dose response studies were performed using the intramuscular or aerosol routes of exposure. All animals succumbed at the lowest target dose; therefore, a dose effect could not be determined. For intramuscular-exposed animals, 100 PFU was the first target dose that was not significantly different than higher target doses in terms of time to disposition, clinical pathology, and histopathology. Although a significant difference was not observed between aerosol-exposed animals in the 10 PFU and 100 PFU target dose groups, 100 PFU was determined to be the lowest target dose that could be consistently obtained and accurately titrated in aerosol studies.

Peripheral doses from pediatric IMRT

International Nuclear Information System (INIS)

Klein, Eric E.; Maserang, Beth; Wood, Roy; Mansur, David

2006-01-01

Peripheral dose (PD) data exist for conventional fields (≥10 cm) and intensity-modulated radiotherapy (IMRT) delivery to standard adult-sized phantoms. Pediatric peripheral dose reports are limited to conventional therapy and are model based. Our goal was to ascertain whether data acquired from full phantom studies and/or pediatric models, with IMRT treatment times, could predict Organ at Risk (OAR) dose for pediatric IMRT. As monitor units (MUs) are greater for IMRT, it is expected IMRT PD will be higher; potentially compounded by decreased patient size (absorption). Baseline slab phantom peripheral dose measurements were conducted for very small field sizes (from 2 to 10 cm). Data were collected at distances ranging from 5 to 72 cm away from the field edges. Collimation was either with the collimating jaws or the multileaf collimator (MLC) oriented either perpendicular or along the peripheral dose measurement plane. For the clinical tests, five patients with intracranial or base of skull lesions were chosen. IMRT and conventional three-dimensional (3D) plans for the same patient/target/dose (180 cGy), were optimized without limitation to the number of fields or wedge use. Six MV, 120-leaf MLC Varian axial beams were used. A phantom mimicking a 3-year-old was configured per Center for Disease Control data. Micro (0.125 cc) and cylindrical (0.6 cc) ionization chambers were appropriated for the thyroid, breast, ovaries, and testes. The PD was recorded by electrometers set to the 10 -10 scale. Each system set was uniquely calibrated. For the slab phantom studies, close peripheral points were found to have a higher dose for low energy and larger field size and when MLC was not deployed. For points more distant from the field edge, the PD was higher for high-energy beams. MLC orientation was found to be inconsequential for the small fields tested. The thyroid dose was lower for IMRT delivery than that predicted for conventional (ratio of IMRT/cnventional ranged from

Multicultural student group work in higher education: a study on challenges as perceived by students

NARCIS (Netherlands)

Popov, V.; Brinkman, B.; Biemans, H.J.A.; Mulder, M.; Kuznetsov, A.M.; Noroozi, O.

2012-01-01

This paper aims to examine challenges that are inherent in multicultural student group work (MCSG) in higher education and the differences between students from different cultural backgrounds in how they perceive the importance of challenges in MCSG. For this purpose, a 19-item survey was completed

Gamma Radiation Doses In Sweden

International Nuclear Information System (INIS)

Almgren, Sara; Isaksson, Mats; Barregaard, Lars

2008-01-01

Gamma dose rate measurements were performed in one urban and one rural area using thermoluminescence dosimeters (TLD) worn by 46 participants and placed in their dwellings. The personal effective dose rates were 0.096±0.019(1 SD) and 0.092±0.016(1 SD)μSv/h in the urban and rural area, respectively. The corresponding dose rates in the dwellings were 0.11±0.042(1 SD) and 0.091±0.026(1 SD)μSv/h. However, the differences between the areas were not significant. The values were higher in buildings made of concrete than of wood and higher in apartments than in detached houses. Also, 222 Rn measurements were performed in each dwelling, which showed no correlation with the gamma dose rates in the dwellings

Influence of radiation dose on positive surgical margins in women undergoing breast conservation therapy

International Nuclear Information System (INIS)

DiBiase, Steven J.; Komarnicky, Lydia T.; Heron, Dwight E.; Schwartz, Gordon F.; Mansfield, Carl M.

2002-01-01

Purpose: Positive surgical margins adversely influence local tumor control in breast conservation therapy (BCT). However, reports have conflicted regarding whether an increased radiation dose can overcome this poor prognostic factor. In this study, we evaluated the influence of an increased radiation dose on tumor control in women with positive surgical margins undergoing BCT. Methods and Materials: Between 1978 and 1994, 733 women with pathologic Stage I-II breast cancer and known surgical margin status were treated at Thomas Jefferson University Hospital with BCT. Of these 733 patients, 641 women had a minimal tumor bed dose of 60 Gy and had documentation of their margin status; 509 had negative surgical margins, and 132 had positive surgical margins before definitive radiotherapy. Complete gross excision of the tumor and axillary lymph node sampling was obtained in all patients. The median radiation dose to the primary site was 65.0 Gy (range 60-76). Of the women with positive margins (n=132), the influence of higher doses of radiotherapy was evaluated. The median follow-up time was 52 months. Results: The local tumor control rate for patients with negative margins at 5 and 10 years was 94% and 88%, respectively, compared with 85% and 67%, respectively, for those women with positive margins (p=0.001). The disease-free survival rate for the negative margin group at 5 and 10 years was 91% and 82%, respectively, compared with 76% and 71%, respectively, for the positive margin group (p = 0.001). The overall survival rate of women with negative margins at 5 and 10 years was 95% and 90%, respectively. By comparison, for women with positive surgical margins, the overall survival rate at 5 and 10 years was 86% and 79%, respectively (p=0.008). A comparison of the positive and negative margin groups revealed that an increased radiation dose (whether entered as a dichotomous or a continuous variable) >65.0 Gy did not improve local tumor control (p=0.776). On Cox

Multi-dose vitamin d supplementation in stable very preterm infants: Prospective randomized trial response to three different vitamin D supplementation doses.

Science.gov (United States)

Bozkurt, Ozlem; Uras, Nurdan; Sari, Fatma Nur; Atay, Funda Yavanoglu; Sahin, Suzan; Alkan, Ayse Dogan; Canpolat, Fuat Emre; Oguz, Serife Suna

2017-09-01

Preterm newborns are born with lower vitamin D stores. Although vitamin D supplementation is recommended there is no consensus regarding the adequate dose of supplementation for preterm infants. To assess the effect of three different doses of vitamin D supplementation (400, 800 and 1000IU/d) in preterm infants ≤32weeks gestation on the prevalence of vitamin D deficiency and 25(OH) D levels at 36weeks postmenstrual age (PMA). Prospective randomized trial. 121 preterm infants with gestational age of 24-32weeks were randomly allocated to receive 400, 800 or 1000IU/d vitamin D. Serum concentration of 25(OH) D and the prevalence of vitamin D deficiency at 36weeks PMA. Vitamin D deficiency was defined as serum 25(OH) D concentrations vitamin D levels before supplementation. The average 25(OH) vitamin D concentrations at 36weeks PMA were significantly higher in 800IU (40±21.4ng/ml) and 1000IU group (43±18.9ng/ml) when compared to 400IU group (29.4±13ng/ml). The prevalence of vitamin D deficiency (2.5 vs 22.5; RR: 0.09; CI:0.01-0.74) and insufficiency (30 vs 57.5; RR:0.32; CI:0.13-0.80) was significantly lower in 1000IU group when compared to 400IU group at 36weeks PMA. 1000IU/d of vitamin D supplementation in preterm infants ≤32weeks gestation age effectively decreases the prevalence of vitamin D deficiency and leads to higher concentrations of 25(OH) vitamin D at 36weeks PMA TRIAL REGISTRATION: Clinical Trials.gov: NCT02941185. Copyright © 2017. Published by Elsevier B.V.

A double-blind, placebo-controlled, randomised, parallel-group, dose-escalating, repeat dose study in healthy volunteers to evaluate the safety, tolerability, pharmacodynamic effects and pharmacokinetics of the once daily rectal application of NRL001 suppositories for 14 days.

Science.gov (United States)

Bell, D; Duffin, A; Jacobs, A; Pediconi, C; Gruss, H J

2014-03-01

The 1R,2S stereoisomer of methoxamine hydrochloride, NRL001, is a highly selective α1-adrenoceptor agonist being developed for the local treatment of non-structural faecal incontinence caused by weak internal anal sphincter tone. This study investigated the steady state pharmacokinetics (PK) and safety of 2 g rectal suppositories containing NRL001 in different strengths (7.5, 10, 12.5 or 15 mg). Healthy volunteers aged 18-45 years received 14 daily doses of NRL001 2 g suppositories or matching placebo. In each dose group nine participants received NRL001 and three received placebo. Blood samples to determine NRL001 concentrations were taken on Days 1, 7 and 14. Cardiovascular parameters were collected via electrocardiograms, Holter monitoring (three lead Holter monitor) and vital signs. Forty-eight volunteers were enrolled; 43 completed the study and were included in the PK analysis population. AUC and Cmax broadly increased with increasing dose, Tmax generally occurred between 4.0 and 5.0 h. Although the data did not appear strongly dose proportional, dose proportionality analysis did not provide evidence against dose proportionality as the log(dose) coefficients were not significantly < 1. NRL001 did not accumulate over time for any dose. Increasing NRL001 concentrations were related to changes in vital sign variables, most notably decreased heart rate. The most commonly reported adverse events (AEs) in the active treatment groups were paraesthesia and piloerection. Treatment with NRL001 was generally well tolerated over 14 days once daily dosing and plasma NRL001 did not accumulate over time. Treatment was associated with changes in vital sign variables, most notably decreased heart rate. AEs commonly reported with NRL001 treatment were events indicative of a systemic α-adrenergic effect. Colorectal Disease © 2014 The Association of Coloproctology of Great Britain and Ireland.

A single dose of dapagliflozin, an SGLT-2 inhibitor, induces higher glycosuria in GCK- and HNF1A-MODY than in type 2 diabetes mellitus.

Science.gov (United States)

Hohendorff, J; Szopa, M; Skupien, J; Kapusta, M; Zapala, B; Platek, T; Mrozinska, S; Parpan, T; Glodzik, W; Ludwig-Galezowska, A; Kiec-Wilk, B; Klupa, T; Malecki, M T

2017-08-01

SGLT2 inhibitors are a new class of oral hypoglycemic agents used in type 2 diabetes (T2DM). Their effectiveness in maturity onset diabetes of the young (MODY) is unknown. We aimed to assess the response to a single dose of 10 mg dapagliflozin in patients with Hepatocyte Nuclear Factor 1 Alpha (HNF1A)-MODY, Glucokinase (GCK)-MODY, and type 2 diabetes. We examined 14 HNF1A-MODY, 19 GCK-MODY, and 12 type 2 diabetes patients. All studied individuals received a single morning dose of 10 mg of dapagliflozin added to their current therapy of diabetes. To assess the response to dapagliflozin we analyzed change in urinary glucose to creatinine ratio and serum 1,5-Anhydroglucitol (1,5-AG) level. There were only four patients with positive urine glucose before dapagliflozin administration (one with HNF1A-MODY, two with GCK-MODY, and one with T2DM), whereas after SGLT-2 inhibitor use, glycosuria occurred in all studied participants. Considerable changes in mean glucose to creatinine ratio after dapagliflozin administration were observed in all three groups (20.51 ± 12.08, 23.19 ± 8.10, and 9.84 ± 6.68 mmol/mmol for HNF1A-MODY, GCK-MODY, and T2DM, respectively, p MODY, respectively), but not between the two MODY forms (p = 0.7231). Significant change in serum 1,5-AG was noticed only in T2DM and it was -6.57 ± 7.34 mg/ml (p = 0.04). A single dose of dapagliflozin, an SGLT-2 inhibitor, induces higher glycosuria in GCK- and HNF1A-MODY than in T2DM. Whether flozins are a valid therapeutic option in these forms of MODY requires long-term clinical studies.

Frequencies of aneuploidy and dominant lethal mutations in young female mice induced by low dose γ-rays

International Nuclear Information System (INIS)

Yao Suyan; Zhang Chaoyang; Dai Lianlian; Gao Changwen

1991-01-01

Relationship between aneuploidy, dominant lethal mutations and doses in young feral mice induced by low dose γ-rays was examined. The results suggest that the frequencies of aneuploidy of embryos increased at 0.15 Gy, but increases at over 0.50 Gy after irradiation in groups. The frequencies of aneuploidy and dominant lethal mutations increased with increasing doses and fitted linear relationship. This dose-response relationship of trisomic was not significant. The frequency of dominant lethal mutations induced by 60 Co γ irradiation is 5.59%. The effect of dominant lethal mutation is higher than that of the aneuploidy

Study of four week repeated dose toxic test of Sweet Bee Venom in Beagle Dogs

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Jae-Seuk Park

2010-12-01

Full Text Available Objectives: This study was performed to analyse four week repeated dose toxicity of Sweet Bee Venom(Sweet BV extracted from the bee venom in Beagle dogs. Methods: All experiments were conducted under the regulations of Good Laboratory Practice (GLP at Biotoxtech Company, a non-clinical study authorized institution. Male and female Beagle dogs of 5-6 months old were chosen for the pilot study of four week repeated dose toxicity of Sweet BV which was administered at the level of 0.56㎎/㎏ body weight which is eighty times higher than the clinical application dosage as the high dosage, followed by 0.28 and 0.14㎎/㎏ as midium and low dosage, respectively. Equal amount of excipient(normal saline to the Sweet BV experiment groups was administered as the control group every day for four weeks. Results: 1. No mortality was witnessed in all of the experiment groups. 2. All experiment groups were appealed pain sense in the treating time compared to the control group, and hyperemia and movement disorder were observed around the area of administration in all experiment groups, and higher occurrence in the higher dosage treatment. 3. For weight measurement, Neither male nor female groups showed significant changes. 4. In the urine analysis, CBC and biochemistry didn't show any significant changes in the experiment groups compared with control group. 5. For weight measurement of organs, experiment groups didn't show any significant changes compared with control group. 6. To verify abnormalities of organs and tissues, thigh muscle which treated with Sweet BV, cerebrum, liver, lung, kidney, and spinal cords were removed and conducted histologocal observation with H-E staining. In the histologocal observation of thigh muscle, cell infiltration, inflammatory, degeneration, necrosis of muscle fiber, and fibrosis were found in both thigh tissue. And the changes were depend on the dose of Sweet BV. But another organs were not detected in any abnormalities. 7

Efficacy of Analgesic Effects of Low Dose Intrathecal Clonidine as Adjuvant to Bupivacaine

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B S Sethi

2007-01-01

The maximum dose of clonidine used was70 μg. The meantime from injection to regression of the level of sensory analgesia by two segments was longer in the Clonidine group than in Control group (P< 0.001. The duration of motor blockade was longer in Clonidine group than in Control group (P< 0.05. There was also a significant difference in the duration of analgesia between the two groups (P< 0.001. The rescue analgesia was required earlier in the Control group(mean 223 min compared to the Clonidine group(mean614 min. The number of injections of diclofenacin24 hours was higher for Control group (mean2.66 than Clonidine group (mean 1.16 (P < 0.05. The patients in the Clonidine group had a significant fall in mean arterial pressure and heart rate and were more sedated than those in Control group, however, no therapeutic interventions needed. We concluded that addition of clonidine to bupivacaine in the dose of 1μg.kg -1 significantly increases the duration of spinal analgesia as compared to bupivacaine alone with clinically insignificant influence on haemodynamic parameters and level of sedation.

Efficacy of tofacitinib in patients with rheumatoid arthritis stratified by background methotrexate dose group.

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Fleischmann, R; Mease, P J; Schwartzman, S; Hwang, L-J; Soma, K; Connell, C A; Takiya, L; Bananis, E

2017-01-01

Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA). This post hoc analysis investigated the effect of methotrexate (MTX) dose on the efficacy of tofacitinib in patients with RA. ORAL Scan (NCT00847613) was a 2-year, randomized, Phase 3 trial evaluating tofacitinib in MTX-inadequate responder (IR) patients with RA. Patients received tofacitinib 5 or 10 mg twice daily (BID), or placebo, with low (≤12.5 mg/week), moderate (>12.5 to tofacitinib 5 mg BID (N = 321), tofacitinib 10 mg BID (N = 316), or placebo (N = 160); 242, 333, and 222 patients received low, moderate, and high MTX doses, respectively. At months 3 and 6, ACR20/50/70 response rates were greater for both tofacitinib doses vs placebo across all MTX doses. At month 3, mean changes from baseline in CDAI and HAQ-DI were significantly greater for both tofacitinib doses vs placebo, irrespective of MTX category; improvements were maintained at month 6. Both tofacitinib doses demonstrated improvements in DAS28-4(ESR), and less structural progression vs placebo, across MTX doses at month 6. Tofacitinib plus MTX showed greater clinical and radiographic efficacy than placebo in MTX-IR patients with RA, regardless of MTX dose.

Influence of dose, age at the onset of disease and ultrasonographic findings of the thyroid gland on the early outcome of the radioiodine treatment of hyperthyroidism

International Nuclear Information System (INIS)

Ugrinska, A.; Pop Gjorceva, D.; Muratovska, L.; Crcareva, B.; Stojanovski, S.

2007-01-01

Full text: Aim of the study: Estimation of the early effects of the treatment of hyperthyroidism with radioactive iodine in correlation with the radioiodine dose, the age at the onset of disease and ultrasonographic (US) findings of the thyroid. Material and methods: Retrospective analysis of the files of 80 patients that underwent a radioactive iodine treatment from the period of 1987 till 2006 because of a diffuse hyperthyroid goiter was performed. The patients were divided in two groups. Group C consisted of patients who were treated with calculated doses from 60-100μC/ml gland volume and group NC who received higher, non-calculated doses. According to age at the onset of disease patients were divided in two groups- group A younger than 40 years and group B older than 40 years. According to the US findings of the thyroid prior to radioiodine therapy patients were divided in two groups group N with predominantly normal US findings and group H with predominantly hypoechoic structure. Results: One year after the application of radioactive iodine 58% of the patients from the group C still remained hyperthyroid, 29% became euthyroid and only 13% developed early hypothyroidism. In the NC group only 7% remained hyperthyroid, 40% were euthyroid, while 54% of the patients developed early hypothyroidism. The occurrence of early hypothyroidism was significantly more frequent in NC than in C group (58% vs. 32%, p<0.05). The age was predictor for the probability of development of early hypothyroidism in C group: only 13% younger in group A, but 46% older patients from group B developed an early hypothyroidism. In the NC group the age was not a predictive factor. In 44 patients there were available records on the US findings prior to radioiodine therapy. In the N group patients that received calculated dose of radioiodine therapy remained euthyroid in 86%, while the patients that received non-calculated dose achieved euthyroidism only in 30%.In the H group there was no

Efficacy of albendazole against nematode parasites isolated from a goat farm in Ethiopia: relationship between dose and efficacy in goats.

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Eguale, Tadesse; Chaka, Hassen; Gizaw, Daniel

2009-10-01

A suspected case of albendazole resistance in a goat farm of Hawassa University was examined using faecal egg count reduction test (FECRT), controlled anthelmintic efficacy test and egg hatch assay (EHA) to verify the development of resistance and/or the need for higher doses of the drug in goats than in sheep. The experiment was conducted in 12 sheep (2 groups: treatment versus control) and 24 goats (4 groups: 3 treatments versus control, n = 6; per group) following artificial infection with infective larvae of Haemonchus contortus and Oesophagostomum columbianum. The first group of sheep and goats were treated orally with albendazole at the dose rate of 3.8 mg/kg body weight (i.e. manufacturer's recommended dose for sheep) while the second group of sheep and the fourth group of goats were left untreated. The second and the third group of goats were treated with albendazole at 5.7 and 7.6 mg/kg respectively. The FECRT showed an efficacy of albendazole in goats to be 65.5, 81.4 and 84.1% at the dose rate of 3.8, 5.7 and 7.6 mg/kg body weight respectively while in sheep it was 62% at the dose rate of 3.8 mg/kg. Increasing the dose to 1.5 the sheep recommended dose induced minor improvement of efficacy in goats; however the efficacy was almost the same at 1.5 and twice the dose recommended for sheep. Worm counts at day 15 post-treatment revealed that H. contortus has developed resistance to albendazole. EHA results also supported these findings. On the other hand, O. columbianum was 100% susceptible at all dose levels tested.

Comparing the Efficacy of Low Dose and Conventional Dose of Oral Isotretinoin in Treatment of Moderate and Severe Acne Vulgaris.

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Faghihi, Gita; Mokhtari, Fatemeh; Fard, Nasrin Motamedi; Motamedi, Narges; Hosseini, Sayed Mohsen

2017-01-01

This study was conducted to compare the effect of low-dose isotretinoin with its conventional dose in patients with moderate and severe acne. This was a clinical trial conducted on 60 male and female patients with moderate and severe acne vulgaris. The patients were divided into two treatment groups: 0.5 mg/kg/day isotretinoin capsule and low-dose isotretinoin capsule (0.25 mg/kg/day). Patients in both groups received 6-month treatment. At the end of the 6 th month and 12 th month (6 months after the end of the treatment), they were examined again, and their improvement was determined and compared. The average severity of acne in the two treatment groups did not differ significantly within any of the study periods. The most common side effects were nose dryness in the low-dose group (17%) and hair thinning and loss in the conventional-dose group (33.2%), although all the patients had dry lips. According to the same severity of the acne in two groups in different study periods, as well as fewer side effects and more patients' satisfaction, the low-dose isotretinoin can be considered in the treatment of acne.

Assessment of Regional Pediatric Computed Tomography Dose Indices in Tamil Nadu.

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Saravanakumar, A; Vaideki, K; Govindarajan, K N; Jayakumar, S; Devanand, B

2017-01-01

The aim of this article is to assess Tamil Nadu pediatric computed tomography (CT) diagnostic reference levels (DRLs) by collecting radiation dose data for the most commonly performed CT examinations. This work was performed for thirty CT scanners installed in various parts of the Tamil Nadu region. The patient cohort was divided into two age groups: <1 year, and 1-5 years. CT dose indices were measured using a 10 cm 3 pencil ion chamber with pediatric head and body polymethyl methacrylate phantoms. Dose data such as volumetric CT dose index (CTDI v ) and dose length product (DLP) on a minimum of twenty average-sized pediatric patients in each category were recorded to calculate a mean site CTDI v and DLP value. The rounded 75 th percentile was used to calculate a pediatric DRL for each hospital, and then region by compiling all results. Data were collected for 3600 pediatric patients. Pediatric CT DRL for two age groups: <1 year (CTDI v and DLP of head [20 mGy, 352 mGy.cm], chest [7 mGy, 120 mGy.cm] and abdomen [12 mGy, 252 mGy.cm]), and 1-5 years (CTDI v and DLP of head [38 mGy, 505 mGy.cm], chest [8 mGy, 132 mGy.cm] and abdomen [14 mGy, 270 mGy.cm]) for select procedures have been calculated. Proposed pediatric DRLs of CTDI v and DLP for head procedure were lower, and for chest and abdomen procedures were higher than European pediatric DRLs for both age groups.

A comparative study of itraconazole in various dose schedules in the treatment of pulmonary aspergilloma in treated patients of pulmonary tuberculosis

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Prahlad Rai Gupta

2015-01-01

Full Text Available Introduction: The optimal dose, duration, and efficacy of itraconazole in Indian patients of pulmonary aspergilloma (PA are not clearly defined. Therefore, a study was carried out, to resolve these issues in diagnosed cases of PA complicating old treated patients of pulmonary tuberculosis. Materials and Methods: The study patients randomly received itraconazole either in a fixed dose schedule of 200 mg (group I, 200 mg twice daily (group II or a variable dose schedule (group III, for 12 months. All the patients were followed up for the entire duration of the study for clinical, radiological, and immunological response. The side effects were recorded as and when reported by the patients and managed symptomatically. Results: A total of 60 patients were enrolled, 20, in each group. There were no intergroup differences with regard to age, sex, body weight, smoking status, alcohol intake, symptoms, Potassium hydroxide (KOH mount, fungal culture, pattern of radiological lesions or anti-aspergillus antibodies (anti-Asp-Ab titers. The radiological response was poor in group I patients, as compared to the other groups, at two months (P < 0.05. The dose of itraconazole was increased in five of the patients in group I due to poor response. A higher number of group II patients suffered side effects and the dose of itraconazole had to be decreased in three of these patients, but none of the patients on a variable dose schedule required a change in dose schedule. Conclusion: Thus, a weight-based variable dose schedule of itraconazole was found to be a more effective and safer modality in the management of PA than a fixed dose schedule.

Acute genitourinary toxicity after high-dose-rate (HDR) brachytherapy combined with hypofractionated external-beam radiation therapy for localized prostate cancer: Correlation between the urethral dose in HDR brachytherapy and the severity of acute genitourinary toxicity

International Nuclear Information System (INIS)

Akimoto, Tetsuo; Ito, Kazuto; Saitoh, Jun-ichi; Noda, Shin-ei; Harashima, Koichi; Sakurai, Hideyuki; Nakayama, Yuko; Yamamoto, Takumi; Suzuki, Kazuhiro; Nakano, Takashi; Niibe, Hideo

2005-01-01

computed tomography images. The number of patients in each fractionation group was as follows: 13 in the 5-Gy group; 19 in the 7-Gy group, and 38 in the 9-Gy group. The tumor stage was T1 in 10 patients, T2 in 36 patients, and T3 in 24 patients. The Gleason score was 2-6 in 11 patients, 7 in 34 patients, and 8-10 in 25 patients. Androgen ablation was performed in all the patients. The median follow-up duration was 14 months (range 3-42 months). The toxicities were graded based on the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer toxicity criteria. Results: The main symptoms of acute GU toxicity were dysuria and increase in urinary frequency or nocturia. The grade distribution of acute GU toxicity in the patients was as follows: Grade 0-1, 39 patients (56%), and Grade 2-4, 31 patients (44%). One patient who developed acute urinary obstruction was classified as having Grade 4 toxicity. Comparison of the distribution of the grade of acute GU toxicity among the different fractionation groups revealed no statistically significant differences among the groups. The urethral dose in HDR brachytherapy was evaluated using the following DVH parameters: V30 (percentage of the urethral volume receiving 30% of the prescribed radiation dose), V80, V90, V100, V110, V120, V130, and V150. The V30-110 values in the patients with Grade 2-4 acute GU toxicity were significantly higher than those in patients with Grade 0-1 toxicity. On the other hand, there were no significant differences in the V120-150 values between patients with Grade 0-1 and Grade 2-4 toxicity. Regarding the influence of the number of needles implanted for the radiation therapy, patients with 11 needles or less showed a significantly higher incidence of Grade 2-4 acute GU toxicity compared with those with 12 needles or more (p < 0.05). Conclusions: It was concluded that HDR brachytherapy combined with hypofractionated EBRT is feasible for localized prostate cancer when

Effects of low dose gamma radiation on the early growth of red pepper and the resistance to subsquent high dose of radiation

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Kim, J. S.; Baek, M. H.; Kim, D. H.; Lee, Y. K. [KAERI, Taejon (Korea, Republic of); Lee, Y. B. [Chungnam National Univ., Taejon (Korea, Republic of)

2001-05-01

Red pepper (capsicum annuum L. cv. Jokwang and cv. Johong) seeds were irradiated with the dose of 0{approx}50 Gy to investigated the effect of the low dose gamma radiation on the early growth and resistance to subsequent high dose of radiation. The effect of the low dose gamma radiation on the early growth and resistance to subsequenct high dose of radiation were enhanced in Johong cultivar but not in Jokwang cultivar. Germination rate and early growth of Johong cultivar were noticeably increased at 4 Gy-, 8 Gy- and 20 Gy irradiation group. Resistance to subsequent high dose of radiation of Johong cultivar were increased at almost all of the low dose irradiation group. Especially it was highest at 4 Gy irradiation group. The carotenoid contents and enzyme activity on the resistance to subsequent high dose of radiation of Johong cultivar were increased at the 4 Gy and 8 Gy irradiation group.

Interaction of 2-Gy Equivalent Dose and Margin Status in Perioperative High-Dose-Rate Brachytherapy

International Nuclear Information System (INIS)

Martinez-Monge, Rafael; Cambeiro, Mauricio; Moreno, Marta; Gaztanaga, Miren; San Julian, Mikel; Alcalde, Juan; Jurado, Matias

2011-01-01

Purpose: To determine patient, tumor, and treatment factors predictive of local control (LC) in a series of patients treated with either perioperative high-dose-rate brachytherapy (PHDRB) alone (Group 1) or with PHDRB combined with external-beam radiotherapy (EBRT) (Group 2). Patient and Methods: Patients (n = 312) enrolled in several PHDRB prospective Phase I-II studies conducted at the Clinica Universidad de Navarra were analyzed. Treatment with PHDRB alone, mainly because of prior irradiation, was used in 126 patients to total doses of 32 Gy/8 b.i.d. or 40 Gy/10 b.i.d. treatments after R0 or R1 resections. Treatment with PHDRB plus EBRT was used in 186 patients to total doses of 16 Gy/4 b.i.d. or 24 Gy/6 b.i.d. treatments after R0 or R1 resections along with 45 Gy of EBRT with or without concomitant chemotherapy. Results: No dose-margin interaction was observed in Group 1 patients. In Group 2 patients there was a significant interaction between margin status and 2-Gy equivalent (Eq2Gy) dose (p = 0.002): (1) patients with negative margins had 9-year LC of 95.7% at Eq2Gy = 62.9Gy; (2) patients with close margins of >1 mm had 9-year LC of 92.4% at Eq2Gy = 72.2Gy, and (3) patients with positive/close <1-mm margins had 9-year LC of 68.0% at Eq2Gy = 72.2Gy. Conclusions: Two-gray equivalent doses ≥70 Gy may compensate the effect of close margins ≥1 mm but do not counterbalance the detrimental effect of unfavorable (positive/close <1 mm) resection margins. No dose-margin interaction is observed in patients treated at lower Eq2Gy doses ≤50 Gy with PHDRB alone.

Dose- and age-dependent cardiovascular mortality among inhabitants of the Chornobyl contaminated areas. 1988-2010 observation period

International Nuclear Information System (INIS)

Buzunov, V.O.; Prikashchikova, K.Je.; Domashevs'ka, T.Je.; Kostyuk, G.V.; Gubyina, Yi.G.; Tereshchenko, S.O.

2014-01-01

Cardiovascular mortality among inhabitants of contaminated areas of Ukraine is dependent on the total cumulative effective doses and age at the time of the Chornobyl accident. It is proved by a significantly higher (p < 0.05) mortality in people exposed to 21.00-50.0 mSv radiation doses compared to those having 5.6-20.99 mSv exposures. Mortality was significantly higher (p < 0.05) in age groups with higher doses as opposed to those with low ones. Maximum mortality was observed among inhabitants aged 40-60, while the lowest death rate - in patients younger than 18 years old. The data obtained also suggest that the radiation factor can be considered here as one accelerating the aging and pathophysiological abnormalities in survivors. Coronary heart disease, cerebrovascular disease, arterial hypertension, diseases of arteries, arterioles and capillaries are the main causes of death from cardiovascular disease in people under investigation

Daily radionuclide ingestion and internal radiation doses in Aomori prefecture, Japan.

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Ohtsuka, Yoshihito; Kakiuchi, Hideki; Akata, Naofumi; Takaku, Yuichi; Hisamatsu, Shun'ichi

2013-10-01

To assess internal annual dose in the general public in Aomori Prefecture, Japan, 80 duplicate cooked diet samples, equivalent to the food consumed over a 400-d period by one person, were collected from 100 volunteers in Aomori City and the village of Rokkasho during 2006–2010 and were analyzed for 11 radionuclides. To obtain average rates of ingestion of radionuclides, the volunteers were selected from among office, fisheries, agricultural, and livestock farm workers. Committed effective doses from ingestion of the diet over a 1-y period were calculated from the analytical results and from International Commission on Radiological Protection dose coefficients; for 40K, an internal effective dose rate from the literature was used. Fisheries workers had significantly higher combined internal annual dose than the other workers, possibly because of high rates of ingestion of marine products known to have high 210Po concentrations. The average internal dose rate, weighted by the numbers of households in each worker group in Aomori Prefecture, was estimated at 0.47 mSv y-1. Polonium-210 contributed 49% of this value. The sum of committed effective dose rates for 210Po, 210Pb, 228Ra, and 14C and the effective dose rate of 40K accounted for approximately 99% of the average internal dose rate.

ON THE ADVISABILITY OF REJECTION OF SUBTRACTION OF BACKGROUND DOSIMETERS INDICATION VALUES FROM THE MEASURED VALUES OF INDIVIDUAL DOSES OF OCCUPATIONAL EXPOSURE OF A-GROUP PERSONNEL

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A. N. Barkovskiy

2013-01-01

Full Text Available An article contains substantiation of advisability of rejection of subtraction of background dosimeters indication values from the measured values of individual doses of occupational exposure of A-group personnel in the process of carrying out of individual dosimetry control of medical organizations stuff which was implemented in the Methodical Guideline 2.6.1.3015-12. It is shown that mentioned procedure is firstly incorrect when we deal with low doses, when the impact of natural exposure could be really considerable and secondary senseless when we deal with dose values close to the dose limit value for A-group personnel when the impact of natural exposure is much lower then the error of measurements. It is suggested to carry out the account of the impact of natural exposure into personnel average doses basing on the analysis of statistical distributions of personnel individual doses and on indications of background dosimeters. It is suggested to add the information about indications of background dosimeters into the Base of Federal Statistical Supervision № 1-DOS as it is prescribed in the Methodical Guideline 2.6.1.3015-12. This article is the respond to the article of A.I. Grigoriev published in the present issue of Journal, in which the author contests the reasonableness of this provision.

Haloperidol dose combined with dexamethasone for PONV prophylaxis in high-risk patients undergoing gynecological laparoscopic surgery: a prospective, randomized, double-blind, dose-response and placebo-controlled study.

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Joo, Jin; Park, Yong Gyu; Baek, Jungwon; Moon, Young Eun

2015-07-08

Low-dose haloperidol is known to be effective for the prevention of postoperative nausea and vomiting (PONV). However, precise dose-response studies have not been completed, especially in patients at high risk for PONV who require combination therapy. This study sought to identify which dose of haloperidol 1mg or 2mg could be combined with dexamethasone without adverse effects in high-risk patients undergoing gynecological laparoscopic surgery. Female adults (n = 150) with three established PONV risk factors based on Apfel's score were randomized into one of three study groups. At the end of anesthesia, groups H0, H1, and H2 were given intravenous (IV) saline, haloperidol 1 mg, and haloperidol 2 mg, respectively. All patients were given dexamethasone 5 mg during the induction of anesthesia. The overall early (0-2 h) and late (2-24 h) incidences of nausea, vomiting, rescue anti-emetic administration, pain, and adverse effects (cardiac arrhythmias and extrapyramidal effects) were assessed postoperatively. The sedation score was recorded in the postanesthesia care unit (PACU). The total incidence of PONV over 24 h was significantly lower in groups H1 (29 %) and H2 (24 %) than in group H0 (54 %; P = 0.003), but there was no significant difference between groups H1 and H2. In the PACU, group H2 had a higher sedation score than groups H1 and H0 (P haloperidol was equally effective as 2 mg in terms of preventing PONV with the less sedative effect. ClinicalTrials.gov ( NCT01639599 ).

Intravenous Iron Therapy in Patients with Iron Deficiency Anemia: Dosing Considerations

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Todd A. Koch

2015-01-01

Full Text Available Objective. To provide clinicians with evidence-based guidance for iron therapy dosing in patients with iron deficiency anemia (IDA, we conducted a study examining the benefits of a higher cumulative dose of intravenous (IV iron than what is typically administered. Methods. We first individually analyzed 5 clinical studies, averaging the total iron deficit across all patients utilizing a modified Ganzoni formula; we then similarly analyzed 2 larger clinical studies. For the second of the larger studies (Study 7, we also compared the efficacy and retreatment requirements of a cumulative dose of 1500 mg ferric carboxymaltose (FCM to 1000 mg iron sucrose (IS. Results. The average iron deficit was calculated to be 1531 mg for patients in Studies 1–5 and 1392 mg for patients in Studies 6-7. The percentage of patients who were retreated with IV iron between Days 56 and 90 was significantly (p<0.001 lower (5.6% in the 1500 mg group, compared to the 1000 mg group (11.1%. Conclusions. Our data suggests that a total cumulative dose of 1000 mg of IV iron may be insufficient for iron repletion in a majority of patients with IDA and a dose of 1500 mg is closer to the actual iron deficit in these patients.

Current modeling practice may lead to falsely high benchmark dose estimates.

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Ringblom, Joakim; Johanson, Gunnar; Öberg, Mattias

2014-07-01