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71.
OBJECTIVE: The authors evaluated the performance of the Stressful Caregiving Adult Reactions to Experiences of Dying (SCARED) scale, a new tool to assess caregiver exposure to patient distress, and the fear and helplessness evoked by these experiences. METHODS: The SCARED was administered to 76 hospice-patient caregivers (e.g., family members). Major depressive disorder (MDD) was diagnosed with the Structured Clinical Interview for the DSM-IV; complicated grief (CG) "caseness" was diagnosed with the Inventory of Complicated Grief-Caregiver items, and quality-of-life domains were assessed with the Medical Outcomes Survey Short Form-36. RESULTS: Respondents endorsed frequent exposure to each SCARED experience-from 30.3% who mistakenly thought the patient had died, to 80.3% who witnessed the patient in severe pain. Adjusted analyses revealed that the odds of MDD increased by 3.08 for each standard-deviation increase in the SCARED event frequency score and that higher SCARED scores were positively associated (p <0.05) with social and role impairment, less energy, and more negative health perceptions. CONCLUSION: The SCARED may be a clinically useful tool for identifying caregivers at risk for MDD and quality-of-life impairments, as well as potential aspects of caregiving to target for treatment.  相似文献   
72.
A human betaretrovirus (HBRV) has been linked with the autoimmune liver disease, primary biliary cholangitis (PBC), and various cancers, including breast cancer and lymphoma. HBRV is closely related to the mouse mammary tumor virus, and represents the only exogenous betaretrovirus characterized in humans to date. Evidence of infection in patients with PBC has been demonstrated through the identification of proviral integration sites in lymphoid tissue, the major reservoir of infection, as well as biliary epithelium, which is the site of the disease process. Accordingly, we tested the hypothesis that patients with PBC harbor a transmissible betaretrovirus by co-cultivation of PBC patients’ lymph node homogenates with the HS578T breast cancer line. Because of the low level of HBRV replication, betaretrovirus producing cells were subcloned to optimize viral isolation and production. Evidence of infection was provided by electron microscopy, RT-PCR, in situ hybridization, cloning of the HBRV proviral genome and demonstration of more than 3400 integration sites. Further evidence of viral transmissibility was demonstrated by infection of biliary epithelial cells. While HBRV did not show a preference for integration proximal to specific genomic features, analyses of common insertion sites revealed evidence of integration proximal to cancer associated genes. These studies demonstrate the isolation of HBRV with features similar to mouse mammary tumor virus and confirm that patients with PBC display evidence of a transmissible viral infection.  相似文献   
73.
OBJECTIVES: The purpose of this study was to investigate the association between involuntary job loss among workers nearing retirement and long-term changes in depressive symptoms. METHODS: Analyzing data from the first four waves (1992-1998) of the Health and Retirement Survey, we used longitudinal multiple regression in order to assess whether involuntary job loss between Wave 1 and Wave 2 was associated with depressive symptoms at Wave 3 and Wave 4. The study sample included 231 workers who had experienced job loss in the Wave 1-Wave 2 interval and a comparison group of 3,324 nondisplaced individuals. We analyzed the effect of job loss on depressive symptoms both in the full study sample and in subsamples determined by wealth. RESULTS: Among individuals with below median net worth, Wave 1-Wave 2 involuntary job loss was associated with increased depressive symptoms at Wave 3 and Wave 4. We found no effect of involuntary job loss for high net worth individuals at the later survey waves. DISCUSSION: Our findings identify older workers with limited wealth as an important group for which the potential effect of involuntary job separation in the years preceding retirement is ongoing (enduring) adverse mental health.  相似文献   
74.
The heterogeneous population of mammalian taste cells includes several cellular subtypes specializing in distinct physiological functions. They are poorly understood at the single cell level because the available physiological data have generally been obtained from unidentified taste cells. We recorded them from individual taste cells isolated from circumvallate, foliate, and fungiform papilla of the mouse, employing the patch clamp technique, and tried to elucidate whether universal electrophysiological criteria may be established for the identification of functionally different cellular subpopulations. It was found that irrespective of the papillae type, most ( approximately 96%) of robust taste cells could be categorized into three distinct subgroups on the basis of families of whole-cell (WC) currents exhibited in response to membrane polarization. The validity of this quite simple criterion was further confirmed by using different voltage clamp protocols, ion substitutions, and channel blockers to record different ionic currents, including voltage-gated (VG) Ca(2+), inward-rectifying K(+), and hyperpolarization-activated currents. Given that our findings are based on the statistically significant number of recordings, we believe that the electrophysiological identification of taste cells presented here may be effective for further studies on single taste cell physiology, including taste transduction.  相似文献   
75.

Objective

Test of the Electronic Integrated Disease Surveillance System (EIDSS) for epi-analysis and prediction of situation in CCHF foci in Kazakhstan.

Introduction

CCHF foci are reported in 3 southern regions of Kazakhstan with population of 1 million. The ixodic ticks in the area are CCHF carriers. Human infections (3 to 12 cases per year) occur through tick bites and contact with CCHF patient blood. CCHF epidemiological process in Kazakhstan has prominent seasonality (spring-summer period) and the rhythm of epidemic appearances (5–6-years). The rhythmical population incidence rate is associated with natural and climate factors, which govern the increase in the number of ixodic ticks, their infection rate (virus carrier state), and directly correlates with the population density and the livestock number that are the principal tick feeders in nature.

Methods

EIDSS version 4 provides capability to collect, share and process epidemiological, clinical and laboratory data on infectious diseases in medicine, veterinary and environment sectors. It is currently deployed in Kazakhstan at 150 sites of the Ministry of Agriculture (planned up to 271), and at 8 sites of the Ministry of Health (planned up to 23).Three available indicators (for 2007–2011) were used for analysis: population; tick infection rate (relative density of CCHF seropositive tick samples per total number of tested laboratory samples); CCHF human case rate by districts per 10’000.The following procedure was conducted:
  1. Demographic information, diagnosis and location data entry into EIDSS
  2. Tick collection location data, total number of tested samples (pools), and number of seropositive data entry into EIDSS
  3. Correlation joint analysis of data on vectors and epidemiological surveillance in Analysis, Visualization and Reporting (AVR) module

Results

EIDSS generated 12 different maps filtered according to the selected regions, ticks, demographics and CCHF human incidence, aggregated by region, correlated by 3 indicators entered into the database. This allowed visualizing information to support epi-analysis. As a result, for each of the 3 regions specific districts with the highest risk of the CCHF epidemic outbreaks were identified. The resulting information was grouped into 3 clusters of risk with the following criteria: population density, tick infection rate and human cases for each of 25 CCHF-disadvantaged districts (see map). These results predict the epidemic situation in a particular area and support management decisions for planning and correction of preventive anti-tick and anti-epidemic measures and funding requirements.

Conclusions

EIDSS with Natural Vectors and the AVR modules has capabilities for analysis and prediction of epizootic and epidemic processes in vector-borne virus infections foci. It is an easy to use and free-of-charge tool that can become the basic instrument for especially dangerous diseases field epidemiologists as well as for the ministries and local governments for CCHF prophylaxis decision support.  相似文献   
76.
Antibacterial C-geranylflavonoids from Paulownia tomentosa Fruits   总被引:1,自引:0,他引:1  
Eight C-6-geranylflavonoids ( 1- 8) were isolated from an ethanol extract of Paulownia tomentosa fruits. Tomentodiplacone ( 1), 3'- O-methyl-5'-hydroxydiplacone ( 2), 3'- O-methyl-5'- O-methyldiplacone ( 3), and tomentodiplacone B ( 4) were obtained as new compounds, and 3'- O-methyldiplacol ( 5) was isolated for the first time from a natural source. The structures of these new compounds were determined by using mass spectrometry (including HRMS) and 1D and 2D NMR spectroscopy, and the absolute configurations of the compounds were determined by circular dichroism. The antibacterial activities of 1- 8 against seven bacteria and yeast were evaluated.  相似文献   
77.
Noroviruses, a major cause of acute gastroenteritis worldwide, present antigenic diversity that must be considered for the development of an effective vaccine. In this study, we explored approaches to increase the broad reactivity of virus-like particle (VLP) norovirus vaccine candidates. The immunogenicity of a GII.4 "Consensus" VLP that was engineered from sequences of three genetically distinct naturally occurring GII.4 strains was examined for its ability to induce cross-reactive immune responses against different clusters of GII.4 noroviruses. Rabbits immunized with GII.4 Consensus VLPs developed high serum antibody titers against VLPs derived from a number of distinct wild-type GII.4 viruses, including some that had been circulating over 30 years ago. Because the sera exhibited low cross-reactivity with antigenically distinct GI norovirus strains, we investigated the serum antibody response to a bivalent vaccine formulation containing GI.1 (Norwalk virus) and GII.4 Consensus VLPs that was administered to animals under varying conditions. In these studies, the highest homologous and heterologous antibody titers to the bivalent vaccine were elicited following immunization of animals by the intramuscular route using Alhydrogel (Al(OH)(3)) as adjuvant. Our data indicate that the use of both genetically engineered norovirus VLPs that incorporate relevant epitopes from multiple strains and multivalent vaccine formulations increase the breadth of the immune response to diverse variants within a genotype and, thus, prove helpful in the rational design of VLP-based vaccines against human noroviruses.  相似文献   
78.
Although a number of predictors of adherence to mammography screening guidelines have been identified using traditional statistical methods, many women are not screening according to these guidelines. Recursive partitioning may aid in developing novel intervention strategies to promote this screening behavior by identifying subgroups of women that differ on adherence across predictor variables. In a prospective study of 1,229 African-American and White women in Connecticut whose adherence to mammography screening guidelines was ascertained over a 26-month follow-up period from initial screening in 1996-1998, recursive partitioning selected six of 22 candidate predictors and identified subgroups that differed on adherence across predictors by age (40-49 and 50-79 years). Among the five subgroups identified for women aged 50-79 years, the subgroup most adherent to screening guidelines during follow-up included four predictors: a history of adherence, annual family income of 15,000 dollars or more, a belief that mammograms were very useful, and low or moderate perceived breast cancer susceptibility. Among the three subgroups identified for women aged 40-49 years, the most adherent subgroup included only one predictor: receipt of a health-care provider's recommendation to obtain a mammogram. These findings suggest that recursive partitioning may be a useful statistical tool and may aid in developing interventions to promote adherence to mammography screening guidelines.  相似文献   
79.
Summary We consider a standard instrumental variables model contaminated by the presence of a large number of exogenous regressors. In an asymptotic framework where this number is proportional to the sample size, we study the impact of their ratio on the validity of existing estimators and tests. When the instruments are few, the inference using the conventional 2SLS estimator and associated t and J statistics, as well as the Anderson–Rubin and Kleibergen tests, is still valid. When the instruments are many, the LIML estimator remains consistent, but the presence of many exogenous regressors changes its asymptotic variance. Moreover, the conventional bias correction of the 2SLS estimator is no longer appropriate. We provide asymptotically correct versions of bias correction for the 2SLS estimator, derive its asymptotically correct variance estimator, extend the Hansen–Hausman–Newey LIML variance estimator to the case of many exogenous regressors, and propose asymptotically valid modifications of the J overidentification tests based on the LIML and bias‐corrected 2SLS estimators.  相似文献   
80.
Adaptive data-dependent allocation designs are used in phase III clinical trials having two or more competing treatments with sequential entrance of patients, in order to allocate a larger number of patients to the better treatment. The odds ratio is a popular concept for biomedical practitioners; hence, odds-ratio-based adaptive designs could be very useful in practice. Rosenberger et al. (2001 Rosenberger , W. F. , Vidyashankar , A. N. , Agarwal , D. K. ( 2001 ). Covariate-adjusted response-adaptive designs for binary response . J. Biopharm. Stat. 11 : 227236 .[Taylor &; Francis Online] [Google Scholar]) introduced an odds-ratio-based two-treatment response-adaptive design; however, they did not study the properties in details. In this article, we describe these designs by means of urn models and provide limiting results for them. Some properties of the design are also studied numerically. We compare the performance of the proposed design with some possible competitors with respect to a few criteria. A real dataset is used to illustrate the applicability of the proposed design. Thus, we provide a base for using odds-ratio-based response-adaptive designs in practice. We extend our design for covariates and also for more than two treatments. In particular, we study the three-treatment design in this article.  相似文献   
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