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1.
The mechanisms underlying neurologic deficits and delayed neuronal death after ischemia are not fully understood. In the present study, we report that transient cerebral ischemia induces accumulation of ubiquitinated proteins (ubi-proteins) in postsynaptic densities (PSDs). By immunoelectron microscopy, we demonstrated that ubi-proteins were highly accumulated in PSD structures after ischemia. On Western blots, ubi-proteins were markedly increased in purified PSDs at 30 minutes of reperfusion, and the increase persisted until cell death in the CA1 region after ischemia. In the resistant DG area, however, the changes were transient and significantly less pronounced. Deposition of ubi-proteins in PSDs after ischemia correlates well with PSD structural damage in the CA1 region as viewed by electron microscopy. These results suggest that the ubiquitin-proteasome system fails to repair and remove damaged proteins in PSDs. The changes may demolish synaptic neurotransmission, contribute to neurologic deficits, and eventually lead to delayed neuronal death after transient cerebral ischemia.  相似文献   
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BACKGROUND: Metyrapone blocks cortisol synthesis which results in removal of negative feedback, a stimulation of hypothalamic corticotropin releasing factor (CRF) and a reduction in delta sleep. We previously reported a diminished delta sleep and hypothalamic-pituitary-adrenal (HPA) response to metyrapone in men with post-traumatic stress disorder (PTSD). In this study, we aimed to extend these findings to women. METHODS: Three nights of polysomnography were obtained in 17 women with PTSD and 16 controls. On day 3, metyrapone was administered throughout the day up until bedtime. Plasma adrenocorticotropic hormone (ACTH), cortisol, and 11-deoxycortisol were obtained the morning following sleep recordings the day before and after metyrapone administration. RESULTS: There were no significant between-group differences in hormone concentration and delta sleep at baseline. Relative to controls, women with PTSD had decreased ACTH and delta sleep responses to metyrapone. Decline in delta sleep was associated with the magnitude of increase in ACTH across groups. CONCLUSIONS: Similar to our previous findings in men, the ACTH and sleep electroencephalogram response to metyrapone is attenuated in women with PTSD. These results are consistent with a model of downregulation of CRF receptors in an environment of chronically increased CRF activity or with enhanced negative feedback regulation in PTSD.  相似文献   
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The Community‐Engaged Research Team Support (CERTS) program was developed and tested to build research and partnership capacity for community‐engaged research (CEnR) teams. Led by the Northwestern University Clinical and Translational Sciences Institute (NUCATS), the goals of CERTS were: (1) to help community‐academic teams build capacity for conducting rigorous CEnR and (2) to support teams as they prepare federal grant proposal drafts. The program was guided by an advisory committee of community and clinical partners, and representatives from Chicago''s Clinical and Translational Science Institutes. Monthly workshops guided teams to write elements of NIH‐style research proposals. Draft reviewing fostered a collaborative learning environment and helped teams develop equal partnerships. The program culminated in a mock‐proposal review. All teams clarified their research and acquired new knowledge about the preparation of NIH‐style proposals. Trust, partnership collaboration, and a structured writing strategy were assets of the CERTS approach. CERTS also uncovered gaps in resources and preparedness for teams to be competitive for federally funded grants. Areas of need include experience as principal investigators, publications on study results, mentoring, institutional infrastructure, and dedicated time for research.  相似文献   
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Tick-borne encephalitis (TBE) virus is the most important human pathogen transmitted by ticks in Eurasia. Inactivated vaccines are available but require multiple doses and frequent boosters to induce and maintain immunity. Thus far, the goal of developing a safe, live attenuated vaccine effective after a single dose has remained elusive. Here we used a replication-defective (single-cycle) flavivirus platform, RepliVax, to generate a safe, single-dose TBE vaccine. Several RepliVax-TBE candidates attenuated by a deletion in the capsid gene were constructed using different flavivirus backbones containing the envelope genes of TBE virus. RepliVax-TBE based on a West Nile virus backbone (RV-WN/TBE) grew more efficiently in helper cells than candidates based on Langat E5, TBE, and yellow fever 17D backbones, and was found to be highly immunogenic and efficacious in mice. Live chimeric yellow fever 17D/TBE, Dengue 2/TBE, and Langat E5/TBE candidates were also constructed but were found to be underattenuated. RV-WN/TBE was demonstrated to be highly immunogenic in Rhesus macaques after a single dose, inducing a significantly more durable humoral immune response compared with three doses of a licensed, adjuvanted human inactivated vaccine. Its immunogenicity was not significantly affected by preexisting immunity against WN. Immunized monkeys were protected from a stringent surrogate challenge. These results support the identification of a single-cycle TBE vaccine with a superior product profile to existing inactivated vaccines, which could lead to improved vaccine coverage and control of the disease.  相似文献   
8.

Background

The Segway® Personal Transporter? (SPT) is used widely as a means of transport for city sightseeing tours, law enforcement, and professionals working in large facilities and factories.

Methods

We conducted a systematic review of the literature to assess SPT-related injuries. Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines, we queried PubMed from 1990 to 2017. The search terms Segway, personal transporter, and injury were used. Only English-language studies were included. Data were extracted from each article, specifically the sample size, study setting, and design, as well as the prevalence of specific injuries.

Results

A total of six articles were included that included data on 135 patients. Sample size per study varied from 1 to 41 patients. Studies occurred in both the emergency department and inpatient settings, including medical-surgical wards, and intensive care units. The most commonly reported injuries were orthopedic cases (n = 45), maxillofacial cases (n = 13), neurologic cases (n = 8), and thoracic cases (n = 10).

Conclusions

The SPT is an innovative transportation method; however, its use is associated with a wide range of injuries. Many of these injuries require hospital admission and surgical intervention, incurring significant morbidity and high costs.  相似文献   
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This article examines whether female injection drug users (IDUs) who have a history of using mental health services (i.e., one or more psychiatric hospitalizations or counseling) enter types of drug treatment different from those of female IDUs who do not have a history of using mental health services. Data used for this exploration originate from a statewide drug-treatment database covering all women who entered drug treatment in the state of Massachusetts from 1996 to 2001. A total of 7776 women were included in the study. Through the use of logistic regression analysis, the study determined that those female IDUs who had a mental health service history, compared with female IDUs who had no such history, were about two-thirds more likely to enter substance abuse treatment other than detoxification only. Specifically, women with a mental health service history were about 66% more likely to enter substance abuse treatment modalities such as drug-free outpatient counseling, methadone maintenance, and/or long-term residential services rather than detoxification alone. This is a positive result, indicating that female IDUs who have mental health problems and therefore have high needs for effective substance abuse treatment are entering the more intensive and/or longer term modalities likely to lead to better outcomes. Possible factors accounting for this, including the referral process within detoxification centers, the role of community referral agents, and the experience women gain as a consequence of receiving services in more than one service system, are discussed.  相似文献   
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