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31.
Blueprint for schistosomiasis vaccine development   总被引:28,自引:0,他引:28  
A number of different schistosome antigens are capable of partially protecting experimental animals from challenge infection. More than 100 such antigens have been identified, about 15% of which are strongly protective and deemed promising though they do not reach the level close to sterile immunity seen after vaccination with irradiated cercariae. Studies of human correlate reactions, i.e. serological reactions and cytokine responses to schistosomiasis antigens, in individuals living in areas endemic for schistosomiasis have shown associations between certain antigen-specific immune responses and lack of re-infection over time. This approach was applied in Brazil and Egypt where it was possible to epidemiologically follow cohorts of individuals in endemic areas for extended periods of time correlating infection status with immune responses against a panel of well-researched, highly purified vaccine candidates. The immune correlates found were unique to each antigen and could be either positive or negative, i.e. associated with resistance or with susceptibility to re-infection. However, few antigens were clear-cut in this respect, i.e. the majority of them induced ambiguous responses. For example, a single antigen might have a significant positive correlation when antigen-driven interferon (INF)-gamma production is measured but also show a significant negative correlation with respect to the IgG1 titre induced. These observations suggest that there are desirable, antigen-specific immune responses that would be valuable in a vaccine but they also indicate that there are responses that must be avoided. The insights gained should be useful not only for antigen selection but also for vaccine formulation prior to Phase I/II trials in humans. It would be of great value if similar independent, long-term human correlate studies could also be undertaken in areas endemic for Schistosoma japonicum.  相似文献   
32.
The mechanism of gastric mucosal protection by an antiulcer agent, colloidal bismuth subcitrate (CBS), against ethanol-induced injury was investigated using in vivo and in vitro systems. The experiments in vivo were conducted with groups of rats with and without indomethacin pretreatment, and the animals received either a dose of CBS (100 mg/kg) or a vehicle (saline), followed 30 min later by ethanol. In the in vitro studies, gastric mucosa segments were cultured in the presence of CBS, ethanol, or both. The results of in vivo experiments revealed that in the absence of CBS, ethanol caused extensive gastric hemorrhagic lesions which were significantly reduced following CBS pretreatment and this effect of CBS was not prevented by indomethacin. The data obtained with gastric mucosal culture established that in comparison to the controls, ethanol caused a 27% decrease in mucin synthesis, while mucin synthesis in the presence of CBS increased by 48%. The increase in mucin synthesis evoked by CBS was accompanied by the enhanced metabolism of mucosal phosphoinositides, as reflected by a decrease in PI (15%) and PIP2 (30%), and an increase in IP1 (26%) and IP3 (67%). In contrast, ethanol, which exhibited detrimental effect on mucin synthesis, caused a decrease in PIP (35%), IP2 (47%) and IP3 (38%), and an increase in PIP2 (80%), and IP1 (51%). However, when the mucosal culture was carried out in the presence of both CBS and ethanol, the detrimental changes evoked by ethanol on mucin synthesis were prevented, and the phosphoinositide and inositide phosphate distribution patterns were quite similar to those in the mucosa cultured in the presence of CBS only.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
33.

Background

Aggression against doctors involved in after-hours house calls (AHHC) is widely perceived to be high. It is, however, unclear how doctors who perform this service manage the risk of aggressive patients during home visits.

Aims

The aim of this paper is to explore if and how doctors manage the risk of violence against them during AHHC.

Methods

A survey was designed and administered to all 300 Australian-based doctors engaged in AHHC under the National Home Doctor Service (NHDS). The survey was conducted from September 2014 to November 2014.

Results

There were 172 responses (57.3 per cent). Only 43 per cent of respondents adopted personal protective measures. The remaining 57 per cent had none; of those 6 per cent had never considered protective measures, and 31.8 per cent were aware of the risk of violence, but were unsure of what to do. Measures adopted include the use of chaperones/security personnel (34.1 per cent), dependence on surgery policies (31.2 per cent), de-escalation techniques (15.2 per cent), panic buttons (7.2 per cent), personal alarms (6.1 per cent), and others (6.5 per cent). Females were more likely to adopt personal protective measures than males (OR 4.94; p<0.01; CI 1.70–14.34), and Australian-trained doctors were less likely to do so relative to overseas-trained doctors (OR 0.35; p=0.04; CI 0.12–0.99).

Conclusion

Just over half of the doctors involved in AHHC took no precautions against aggressive attacks while on duty, and nearly one-third relied on the policies of their employing surgeries.  相似文献   
34.
《Vaccine》2015,33(48):6800-6808
A replication-deficient chimpanzee adenovirus expressing Ag85A (ChAdOx1.85A) was assessed, both alone and in combination with modified vaccinia Ankara also expressing Ag85A (MVA85A), for its immunogenicity and protective efficacy against a Mycobacterium tuberculosis (M.tb) challenge in mice. Naïve and BCG-primed mice were vaccinated or boosted with ChAdOx1.85A and MVA85A in different combinations. Although intranasally administered ChAdOx1.85A induced strong immune responses in the lungs, it failed to consistently protect against aerosol M.tb challenge. In contrast, ChAdOx1.85A followed by MVA85A administered either mucosally or systemically, induced strong immune responses and was able to improve the protective efficacy of BCG. This vaccination regime has consistently shown superior protection over BCG alone and should be evaluated further.  相似文献   
35.

Introduction

Intravenous alteplase reduces disability and improves functionality among acute ischemic stroke patients. Two decades after its approval, only a small fraction of patients get the treatment, and demonstrating its impact on mortality may make a strong case for its wider use. This study assessed the impact of thrombolytic treatment by alteplase on 1-year mortality and readmission among acute ischemic stroke patients.

Method

The 2008–2013 Georgia Coverdell Acute Stroke Registry data were linked with the 2008–2013 hospital discharge and the 2008–2014 death data in Georgia. Multiple imputation was applied; a propensity score measuring the probability of receiving intravenous alteplase was calculated and used for matching. A conditional logistic regression was applied to compare 1-year mortality and readmission among propensity score matched pairs.

Results

Overall, 20.3% of 9620 acute ischemic stroke patients died and 22.4% were readmitted in one year. The multivariable regression result showed that patients who did not receive IV alteplase had a 1.49 (95%CI: 1.09–2.04; p-value = 0.01) times higher odds of dying at one year than those who were treated with the thrombolytic agent. Among patients discharged home, no statistically significant difference was documented in the odds of being readmitted at least once within 365 days post-stroke discharge.

Discussion and conclusion

After accounting for patient differences and missing value, intravenous alteplase is associated with reduction in long-term mortality. The results of this study suggest that patients who are identified as eligible for intravenous alteplase need to be offered the treatment.  相似文献   
36.
ABSTRACT

Objective: To evaluate the association between sociodemographic factors and eye care expenditure and to assess the burden of ocular expenditure compared to total health care expenditure.

Methods: A retrospective analysis of ocular expenditure in participants of the 2007 Medical Expenditure Panel Survey. Data from 20,620 unique participants aged ≥18 years were evaluated for eye care expenditure by demographic characteristics.

Results: A total of 22% of the studied population had eye care expenditures in 2007. Demographic factors significantly associated with higher probability of having eye care expenditures included older age (65+ years 35%, 45–64 years 23%, <45 years 17%), female sex (female 26%, male 19%), higher educational attainment (greater than high school education 25%, less than high school education 17%), having insurance (private 24%, uninsured 13%), and visual impairment (mild 31%, none 22%). Older age, female sex, higher educational attainment, having insurance, and presence of visual impairment were also significantly associated with higher mean eye care expenditure. In those with eye care expenditure, the mean ratio between eye care and total medical expenditure was 24%, with uninsured patients spending 42% of their medical care expenditure on eye care.

Conclusions: Demographic factors are associated with both the probability of having ocular expenditure and the amount of expenditure. Of all factors examined, insurance status has the most potential for modification. Policy makers should consider these numbers when devising the terms by which eye care coverage will be provided under the Patient Protection and Affordable Care Act.  相似文献   
37.
The current initiative to reform health care from both a quality and a cost perspective has already had a profound impact on the radiology enterprise. We have seen a decrease in the utilization of imaging studies, a reduction in reimbursement, a declining payer mix, shrinking incomes, a proliferation of performance indices, creation of radiology mega-groups, growth of national radiology companies, and increasing turf incursions. Our cheese is clearly on the move, and we must take action to reengineer the radiology enterprise. In keeping with general health care reform, we must be patient-centric, data driven, and outcome based. We must create a radiology enterprise that adheres to the value equation of providing the highest quality health care, for the lowest possible cost, for all citizens.  相似文献   
38.
39.
目的 以定量组织病理学的重要指标节细胞层和内核细胞层的厚度和细胞计数为指标,探讨三七总皂甙和480目铜丝网对高功率微波所致的视网膜损伤进行药物防护和物理防护的效果.方法 将青紫蓝兔分为假辐射对照组、辐射组、三七总皂甙防护组和480目铜丝屏蔽组.观察各实验组视网膜组织的病理形态变化.结果 三七总皂甙预处理能显著减轻高功率微波辐照所致的视网膜组织的病理形态学损伤;480目铜丝网屏蔽防护,能完全屏蔽该频率高功率微波辐射,使视网膜组织结构维持正常,表现出良好的屏蔽防护效果.结论 三七总皂甙和480目铜丝网对高功率微波致视网膜损伤具有药物和物理防护作用,为探讨可供实用的高功率微波眼损伤防护措施提供实验依据.  相似文献   
40.
The Patient Protection and Affordable Care Act of 2010 (ACA) is revamping the access, quality, and financing of the health and mental health systems. However, its impact on training and education in clinical psychology is unclear. This article aims to identify specific components of the ACA, in particular the Mental and Behavioral Health Education and Training Grants, that are expected to affect training and education in the field. The article further connects the ACA with four paradigm shifts in clinical psychology that have broad implications for training and education—evidence‐based practices, research methodology, interprofessionalism, and the quality indicator movement. The overarching goal of this article is to begin timely discussions on the future directions of the field under the current healthcare reform.  相似文献   
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