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91.
Anticholinergic and antiglutamatergic agents protect against soman-induced brain damage and cognitive dysfunction. 总被引:1,自引:0,他引:1
Lily Raveh Rachel Brandeis Eran Gilat Giora Cohen David Alkalay Ishai Rabinovitz Hagar Sonego Ben Avi Weissman 《Toxicological sciences》2003,75(1):108-116
Soman, a powerful inhibitor of acetylcholinesterase, causes an array of toxic effects in the central nervous system including convulsions, learning and memory impairments, and, ultimately, death. We report on the protection afforded by postexposure antidotal treatments, combined with pyridostigmine (0.1 mg/kg) pretreatment, against these consequences associated with soman poisoning. Scopolamine (0.1 mg/kg) or caramiphen (10 mg/kg) were administered 5 min after soman (1.2 LD50), whereas TAB (i.e., TMB4, atropine, and benactyzine, 7.5, 3, and 1 mg/kg, respectively) was injected in rats concomitant with the development of toxic signs. Atropine (4 mg/kg) was given to the two former groups at the onset of toxic symptoms. Caramiphen and TAB completely abolished electrographic seizure activity while scopolamine treatment exhibited only partial protection. Additionally, no significant alteration in the density of peripheral benzodiazepine receptors was noted following caramiphen or TAB administration, while scopolamine application resulted in a complex outcome: a portion of the animals demonstrated no change in the number of these sites whereas the others exhibited markedly higher densities. Cognitive functions (i.e., learning and memory processes) evaluated using the Morris water maze improved considerably by the three treatments when compared to soman-injected animals; the following rank order was observed: caramiphen > TAB > scopolamine. Additionally, statistically significant correlations (r = 0.72, r = 0.73) were demonstrated between two learning parameters and [3H]Ro5-4864 binding to brain membrane. These results show that drugs with a pharmacological profile consisting of anticholinergic and antiglutamatergic properties such as caramiphen and TAB, have a substantial potential as postexposure therapies against intoxication by organophosphates. 相似文献
92.
Thomas C Neylan Maryanne Lenoci Melissa L Maglione Nicholas Z Rosenlicht Thomas J Metzler Christian Otte Frank B Schoenfeld Rachel Yehuda Charles R Marmar 《Neuropsychopharmacology》2003,28(9):1666-1676
Metyrapone blocks cortisol synthesis, which results in the stimulation of hypothalamic cortiocotropin-releasing factor (CRF) and a reduction in delta sleep. We examined the effect of metyrapone administration on endocrine and sleep measures in male subjects with and without chronic PTSD. We hypothesized that metyrapone would result in a decrease in delta sleep and that the magnitude of this decrease would be correlated with the endocrine response. Finally, we utilized the delta sleep response to metyrapone as an indirect measure of hypothalamic CRF activity and hypothesized that PTSD subjects would have decreased delta sleep at baseline and a greater decrease in delta sleep induced by metyrapone. Three nights of polysomnography were obtained in 24 male subjects with combat-related PTSD and 18 male combat-exposed normal controls. On day 3, metyrapone was administered during normal waking hours until habitual sleep onset preceding night 3. Endocrine responses to metyrapone were measured in plasma obtained the morning following sleep recordings, the day before and after administration. Repeated measures ANOVAs were conducted to compare the endocrine and sleep response to metyrapone in PTSD and controls. PTSD subjects had significantly less delta sleep as indexed by stages 3 and 4, and total delta integrated amplitude prior to metyrapone administration. There were no differences in premetyrapone cortisol or ACTH levels in PTSD vs controls. PTSD subjects had a significantly decreased ACTH response to metyrapone compared to controls. Metyrapone caused an increase in awakenings and a marked decrease in quantitative measures of delta sleep that was significantly greater in controls compared to PTSD. The decline in delta sleep was significantly associated with the magnitude of increase in both 11-deoxycortisol and ACTH. The results suggest that the delta sleep response to metyrapone is a measure of the brain response to increases in hypothalamic CRF. These data also suggest that the ACTH and sleep EEG response to hypothalamic CRF is decreased in PTSD. 相似文献
93.
Bonnie L. Green Lisa A. Goodman Janice L. Krupnick Carole B. Corcoran Rachel M. Petty 《Journal of traumatic stress》2000,13(4):743-744
Note
Acknowledgment of Ad Hoc Reviewers for Volume 13 相似文献94.
Beatrice M Seddon Geoffrey S Payne Laura Simmons Ruth Ruddle Rachel Grimshaw Siew Tan Alison Turner Florence Raynaud Gavin Halbert Martin O Leach Ian Judson Paul Workman 《Clinical cancer research》2003,9(14):5101-5112
PURPOSE: To perform a Phase I study of SR-4554, a fluorinated 2-nitroimidazole noninvasive probe of tumor hypoxia detected by (19)F magnetic resonance spectroscopy (MRS). EXPERIMENTAL DESIGN: SR-4554 administration, on days 1 and 8, was followed by plasma sampling for pharmacokinetic studies and by three MRS studies performed over 24 h on days 8 and 9. Unlocalized MR spectra were acquired from tumor (10- or 16-cm dual resonant 1H/19F surface coil; 1.5 T Siemens Vision MR system; 2048 transients acquired over 34 min; 1.28-ms adiabatic pulse; repetition time, 1 s). Plasma drug concentrations were measured with a validated high-performance liquid chromatography method. Noncompartmental pharmacokinetic analysis was performed. RESULTS: Eight patients underwent pharmacokinetic studies, receiving doses of SR-4554 of 400-1600 mg/m(2). Peak plasma concentrations increased linearly with the SR-4554 dose (r(2) = 0.80; P = 0.0002). The plasma elimination half-life was relatively short (mean +/- SD, 3.28 +/- 0.59 h), and plasma clearance was quite rapid (mean +/- SD, 12.8 +/- 3.3 liters/h). Urinary recovery was generally high. SR-4554 was well tolerated. A single patient experienced dose-limiting toxicity (nausea and vomiting) at 1600 mg/m(2). The maximum tolerated dose was 1400 mg/m(2). SR-4554 was detected spectroscopically in tumors immediately after infusion at doses of 400-1600 mg/m(2). At the highest dose (1600 mg/m(2)), SR-4554 was detectable in tumor at 8 h, but not at 27 h. CONCLUSIONS: SR-4554 has plasma pharmacokinetic and toxicity profiles suitable for use as a hypoxia probe. It can be detected in tumors by unlocalized MRS. Additional clinical studies are warranted. 相似文献
95.
Mitchell Maiman M.D. Rachel G. Fruchter Ph.D. Alexander Sedlis M.D. Joseph Feldman Dr.P.H. Patrick Chen M.D. Robert D. Burk M.D. Howard Minkoff M.D. 《Gynecologic oncology》1998,68(3):233-239
Objectives.The objective was to evaluate the sensitivity and specificity of cervical cytology in women infected with the human immunodeficiency virus (HIV), risk factors for abnormal cytology in HIV-infected and uninfected women, and risk factors for histologic diagnosis of cervical intraepithelial neoplasia (CIN) in HIV-infected women.Methods.Methods included a cross-sectional analysis of cervical cytology, colposcopic impression, and histology in 248 HIV-infected women and multivariate analyses of risk factors for abnormal cytology in 253 HIV-infected and 220 uninfected women and risk factors for CIN in 186 HIV-infected women.Results.The sensitivity and specificity of cytology for all CIN grades were 0.60 and 0.80 and, for high-grade CIN, 0.83 and 0.74. The prevalence of abnormal cytology was 32.9% in HIV-infected and 7.6% in HIV-negative women. Independent risk factors for abnormal cytology were immunodeficiency [odds ratio (OR) 8–17,P< 0.001] and human papillomavirus (HPV) infection (OR = 5,P< 0.001). The prevalence of CIN on histology was 32% in HIV-infected women, and the only independent risk factor for CIN was oncogenic HPV type (OR = 5,P= 0.005).Conclusion.Given the high prevalence of abnormal cytology and CIN in HIV-infected women, cytologic screening has significant limitations. Both immunodeficiency and type of HPV infection are important risk factors. 相似文献
96.
97.
男性与女性糖尿病患者致死性冠心病的额外危险:37个前瞻性队列研究的汇总分析 总被引:6,自引:0,他引:6
目的:估计男性和女性糖尿病患者致死性冠心病的相对危险。设计:前瞻性队列研究的汇总分析。数据来源:自1966年至2005年3月间Embase和Medline确认并发表的研究,加上源自亚太队列研究协作组的研究,采用正文词组与MeSH主题词相结合的策略进行检索。综述方法:对入选研究的要求为报告有或无糖尿病的男性与女性致死性冠心病的相对危险比较的估计值。如果对估计值仅做年龄调整(而其它因素来经调整——泽者注),则将该研究排除在外。结果:总共纳入37项2型糖尿病和致死性冠心病的研究,涉及447064例患者。糖尿病患者的致死性冠心病发生率显著高于非糖尿病患者(5.4%比1.6%)。与无糖尿病者相比,糖尿病患者发生致死性冠心病的总的相对危险,女性为3.50,95%可信区间为2.70~4.53,显著高于男性患者(2.06,95%可信区间1.81~2.34)。在除外8项仅根据年龄调整的研究后,两性之间危险的差异大大减小,但仍然具有极显著统计学意义。汇集29项经多因素调整估计值的研究,总的相对危险比(女性比男性)为1.46(1.14~1.88)。结论:糖尿病相关的致死性冠心病相对危险,女性比男性高出50%。这种额外的冠心病危险可以通过女性糖尿病患者具有更多不利的心血管危险因素特点以及倾向于对男性患者更注重治疗的可能偏差来解释。 相似文献
98.
Melinda L Irwin Anne McTiernan Richard N Baumgartner Kathy B Baumgartner Leslie Bernstein Frank D Gilliland Rachel Ballard-Barbash 《Journal of clinical oncology》2005,23(4):774-782
PURPOSE: Obese women and women who gain weight after a breast cancer diagnosis are at a greater risk for breast cancer recurrence and death compared with lean women and women who do not gain weight after diagnosis. In this population-based study, we assessed weight and body fat changes from during the first year of diagnosis to during the third year after diagnosis, and whether any changes in weight and body fat varied by demographic, prognostic, and lifestyle factors in 514 women with incident Stage 0-IIIA breast cancer. METHODS: Patients were participants in the Health, Eating, Activity, and Lifestyle (HEAL) study. Weight and body fat (via dual-energy x-ray absorptiometry scans) were measured during the baseline visit and 2 years later at a follow-up visit. Analysis of covariance methods were used to obtain mean weight and body fat changes adjusted for potential cofounders. RESULTS: Women increased their weight and percent body fat by 1.7 +/- 4.7 kg and 2.1% +/- 3.9%, respectively, from during their first year of diagnosis to during their third year of diagnosis. A total of 68% and 74% of patients gained weight and body fat, respectively. Greater increases in weight were observed among women diagnosed with a higher disease stage, younger age, being postmenopausal, and women who decreased their physical activity from diagnosis to up to 3 years after diagnosis (P for trend < .05). CONCLUSION: Weight and body fat increased in the postdiagnosis period. Future research should focus on the effect of physical activity on weight and fat loss and breast cancer prognosis. 相似文献
99.
Rachel E Neale Geraldine Mineau David C Whiteman Pat A Brownbill Michael F G Murphy 《Cancer epidemiology, biomarkers & prevention》2005,14(5):1236-1240
OBJECTIVE: Evidence suggests that the in utero environment may contribute to subsequent development of cancers in childhood and adulthood. Raised levels of estrogen during pregnancy may be the primary in utero etiologic factor. Mothers of twins have higher estrogen levels during pregnancy than mothers of singletons, therefore, assessment of cancer risk in twins may be informative.METHOD: We conducted a retrospective cohort study of cancer among twin and singleton newborns selected from the Utah Population Database, matched on birth year and sex. Cancer diagnoses were determined by linkage with the Utah state cancer register. Relative rates of all cancers in childhood and in adulthood in twins compared with singletons, and for specific cancers including testicular, breast and melanoma, were calculated using Poisson regression.RESULTS: Twin (35,271) and singleton (74,199) births were identified, among whom there were 336 and 691 cancer diagnoses, respectively. The relative risk (RR) of childhood cancer in twins compared with singletons was 0.82 [95% confidence interval (CI) 0.55-1.24] and of adult cancer was 1.06 (0.92-1.22). We found nonsignificant increases in risk among adult twins for cancers of the breast, prostate, testis, lymphatic system, thyroid, and large bowel. The largest departures from unity were for testicular cancer (RR 1.47; 95% CI, 0.73-2.95) and melanoma (RR 0.67; 95% CI, 0.42-1.06).CONCLUSIONS: These results are consistent with the body of evidence suggesting that twins have a reduced risk of cancer in childhood. Although there is no overall differential in adult cancer risk, these data support the hypothesis that the in utero environment may play an important role in specific cancers. 相似文献
100.
Bevacizumab--current status and future directions. 总被引:13,自引:0,他引:13
Angiogenesis is crucial to tumour initiation, survival and metastasis. Vascular endothelial growth factor (VEGF) is one of the most important pro-angiogenic factors in cancer development. Bevacizumab (a humanised monoclonal antibody against VEGF) has a reasonable safety profile and proven efficacy in a phase III trial in advanced colorectal cancer. Efficacy of Bevacizumab also looks promising in non small cell lung cancer, renal cancer and a variety of other solid tumours. Questions still surround optimal dosing and the appropriate selection of patients who are most likely to benefit. Future trials will address these questions and provide further translational insights. 相似文献