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Emma L Wignall Jon M Dickson Paul Vaughan Tom F D Farrow Iain D Wilkinson Michael D Hunter Peter W R Woodruff 《Neuropsychopharmacology》2004,56(11):832-836
BACKGROUND: Previous structural magnetic resonance (MR) research in patients with posttraumatic stress disorder (PTSD) has found smaller hippocampal volumes in patients compared with control subjects. These studies have mostly involved subjects who have had PTSD for a number of years, such as war veterans or adult survivors of childhood abuse. Patients with recent-onset PTSD have rarely been investigated. To our knowledge only one other study has investigated such a group. The aim of this study was to compare hippocampal volumes of patients with recent onset PTSD and nontrauma-exposed control subjects. METHODS: Fifteen patients with PTSD, recruited from an accident and emergency department, were compared with 11, non-trauma-exposed, healthy control subjects. Patients underwent a structural MR scan soon after trauma (mean time = 158 +/- 41 days). Entire brain volumes, voxel size 1 x 1 x 1 mm, were acquired for each subject. Point counting and stereology were used to measure the hippocampal and amygdala volume of each subject. RESULTS: Right-sided hippocampal volume was significantly smaller in PTSD patients than control subjects after controlling for effects of whole brain volume and age. Neither left nor total hippocampal volume were significantly smaller in the PTSD group after correction. Whole brain volume was also found to be significantly smaller in patients. There were no differences in amygdala or white matter volumes between patients and control subjects. CONCLUSIONS: This result replicates previous findings of smaller hippocampal volumes in PTSD patients, but in an underinvestigated population, suggesting that either smaller hippocampal volume is a predisposing factor in the development of PTSD or that damage occurs within months of trauma, rather than a number of years. Either of these two hypotheses have significant implications for the treatment of PTSD. For instance, if it could be shown that screening for hippocampal volume may, in some cases, predict those likely to develop clinical PTSD. 相似文献
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Effects of subacute toluene exposure on neuronal and glial marker proteins in rat brain 总被引:2,自引:0,他引:2
The behavior of marker proteins of neurons (gamma-enolase) and glial cells (alpha-enolase, beta-S100 protein and creatine kinase-B) was investigated quantitatively by using enzyme immunoassay systems in toluene-exposed rat brains. Three groups of animals were exposed to toluene vapor at 300 ppm, 1000 ppm, and 3000 ppm, respectively, 8 h/day, 6 days/week, for 2 weeks. After subacute repeated solvent exposure, both neuron-specific gamma-enolase and glial marker proteins displayed an overall concentration-dependent increase tendency in separate brain regions. In cerebrum, only the 3000 ppm group showed a significant increase in alpha-enolase by 27% and creatine kinase-B (CK-B) by 26%. alpha-Enolase and gamma-enolase exhibited a pronounced elevation in cerebellum relative to other brain regions, while beta-S100 protein appeared to be the most markedly altered marker in brainstem. The development of gliosis, which is a frequent phenomenon following CNS damage, is presumed to be responsible for the elevation of glial marker content. Energy metabolism disruption in brain tissues may also bring about the compensatory oversynthesis of glycolytic enzymes such as gamma-enolase, alpha-enolase and CK-B. The dose-dependent alteration patterns following toluene exposure suggest the feasibility of using these brain specific markers to evaluate solvent-induced CNS effects. 相似文献
46.
Masazumi Zaima Keisuke Nagamatsu Akira Mitsuyoshi Shinji Murata Toshihumi Takeuchi Akira Kobayashi 《Urology》1997,49(6):948-950
A new surgical technique to treat retroperitoneal tumors with supradiaphragmatic vena caval invasion is described. In this technique, hepatic warm ischemia can be avoided with reversed hepatic outflow through the portal vein and neither hypothermic circulatory arrest nor cardiopulmonary bypass is necessary using centrifugal blood pump-driven bypass. 相似文献
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Victor W. Acquista M.D. Tom J. Wachtel M.D. Celia I. Gomes M.P.H. Michael Salzillo M.S. Melanie Stockman R.N. 《Journal of community health》1988,13(1):43-52
In an effort to improve Health Risk Appraisals and to induce individuals to change their lifestyles, comprehensive evaluations and counseling sessions were carried out for 476 participants of an experimental preventive care program (1984). Nurse practitioners interviewed participants in their homes and collected information about their lifestyle, medical history, and family history. In addition, physical examinations were performed and blood samples were obtained for laboratory analysis. This information was used to formulate health risk profiles for all participants who were then counseled on how to decrease identified health risks. Interventions included education about health risks and specific programs which were administered to help modify high-risk behaviors. At one year follow-up, significant risk reductions were reported in many areas of increased risk.Victor W. Acquista, M.D., is a Fellow in General Internal Medicine, Rhode Island Hospital. Tom J. Wachtel, M.D., is Director, Medical Primary Care Unit, Rhode Island Hospital, and Assistant Professor of Community Health, Brown University. Celia I. Gomes, M.P.H., is Health Education Coordinator, Blue Cross/Blue Shield of Rhode Island. Michael Salzillo, M.S., is Team Leader, Statistical Analysis Department, Blue Cross/Blue Shield of Rhode Island. Melanie Stockman, R.N., is Director of Ambulatory Nursing, Rhode Island Hospital. 相似文献
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T Kubota H Yamaguchi M Watanabe T Yamamoto T Takahara T Takeuchi T Furukawa S Kase S Kodaira K Ishibiki 《Japanese journal of cancer research》1992,83(3):300-303
We implanted normal peripheral blood lymphocytes (PBL) from healthy donors and splenic tissues from patients with gastric cancers into the severe combined immunodeficient (SCID) mouse, demonstrating that SCID mouse with splenic tissue can produce a high level of human immunoglobulin G (IgG). The normal PBLs at 10(7) and 10(8)/mouse were implanted intraperitoneally, and three splenic tissues with a size of 3 x 3 x 3 mm from gastric cancer patients were inoculated subcutaneously into the bilateral backs of the mice. At 2, 4, 6 and 8 weeks after inoculation, mice were killed, and the human IgG was assessed by an ELISA method. SCID mice with splenic tissue revealed high human IgG levels from 2 weeks after inoculation and approximately 2 mg of IgG per ml was observed at 8 weeks post-implantation, while the IgG levels in mice treated with PBLs were limited. Since the half life of the extrinsic human IgG was 10.2 days, the high level of human IgG in the SCID mice was supposed to be produced by human plasma cells in the splenic tissue from gastric cancer patients. This model was thought to be adequate for evaluating human immunological functions in vivo. 相似文献