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61.

Background

Many individuals with Parkinson''s disease are not diagnosed and treated. Attitudes about aging and related help-seeking may affect the timely diagnosis of Parkinson''s disease. Our objectives were to develop measures of older adults'' expectations regarding movement with aging, specifically related to parkinsonism, and their beliefs about seeking healthcare for the diagnosis and treatment of parkinsonism.

Methods

We established content and face validity from interviews with experts, review of the literature, and pre-testing with key informants. Two 9-item instruments resulted: Expectations Regarding Movement (ERM) and Healthcare Seeking Beliefs for parkinsonism (HSB). These instruments were administered to 210 older adults at senior centers to investigate internal consistency and construct validity.

Results

192 (91%) of the older adults completed more than 90% of the survey. The mean age was 76; 17 (9%) reported parkinsonism. Both scales demonstrated good internal consistency (α = 0.90). Factor analysis supported construct validity of the ERM and HSB scores. Older age, lower education, worse self-reported health and African American race each were associated with lower ERM scores, but not HSB scores.

Conclusion

The ERM, a brief measure of expectations regarding movement with aging, shows reliability and validity. This scale may be useful in identifying older adults at increased risk for under-identification of Parkinson''s disease. Further work is needed to measure healthcare seeking for parkinsonism.  相似文献   
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Background

Detection and treatment of latent TB infection (LTBI) in HIV infected individuals is strongly recommended to decrease morbidity and mortality in countries with high levels of HIV.

Objective

To assess the validity of a newly developed in-house ELISPOT interferon-γ release assay (IGRA) for the detection of LTBI amongst HIV infected individuals, in comparison with the Tuberculin Skin Test (TST).

Methodology/Principal Findings

ESAT6/CFP10 (EC) ELISPOT assays were performed, together with a TST, in 285 HIV infected individuals recruited in HIV clinics in Dakar, Senegal, who had no signs of active TB at time of enrolment. Thirty eight of the subjects (13.3%) failed to respond to PHA stimulation and were excluded from the analysis. In the 247 remaining patients, response to PHA did not vary according to CD4 cell count categories (p = 0.51). EC ELISPOT was positive in 125 (50.6%) subjects, while 53 (21.5%) had a positive TST. Concordance between EC ELISPOT and TST was observed in 151 patients (61.1%) (kappa = 0.23). The proportion of subjects with a positive response to the EC ELISPOT assay decreased with declining CD4 counts (p trend = 0.001), but were consistently higher than the proportion of TST responders. In multivariate analysis, the risk of being EC-ELISPOT positive in HIV infected individuals was associated with age, CD4 count and HIV-1 strain.

Conclusion

Our study indicates that IGRAs using M. tuberculosis specific antigens are likely to retain their validity for the diagnosis of LTBI among HIV positive individuals, but may be impaired by T-cell anergy in severely immuno-suppressed individuals.  相似文献   
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The cerebrospinal fluid (CSF) of multiple sclerosis (MS) patients contains a 17 kDa glycoproteic factor with gliotoxic properties in vitro. In order to study the physiopathological role of this gliotoxic factor in vivo, we have injected a partially purified preparation and appropriate controls in rat CSF and investigated whether it induces cell death in the rat central nervous system (CNS), 10 days and 3 months after injection. We used the TUNEL assay in association with specific immunohistochemistry to characterize dying cells in the gliotoxic factor- treated rat CNS. At 10 days post-injection, TUNEL-positive cells were observed in the whole rat CNS. They were particularly numerous in the choroid plexus, ependymal epithelium, cerebral white matter, cerebral vascular endothelium, arachnoid spaces and less frequent in the gray matter of brain and spinal cord. The predominant type of TUNEL-positive cells observed at 10 days post-injection was astrocytes, in white matter, gray matter, occasionnally around damaged endothelial cells in periventricular and subpial spaces. Other TUNEL-positive cells were identified as oligodendrocytes by an oligodendrocyte specific RIP immunostaining, at 10 days post-treatment with the gliotoxic factor. Interestingly, demyelination and death of oligodendrocytes were more important 3 months post-injection: TUNEL-RIP positive oligodendrocytes were generally associated with multifocal demyelinating areas. Clearly, the 17 kDa gliotoxic factor injection in rat CSF triggers demyelination and may be used as a new animal model for MS. Also, our results suggest a new possible scenario for MS pathogenesis: death of oligodendrocytes and astrocytes, stimulated by the MS gliotoxic factor causes the breakdown of the blood-brain barrier (BBB) and the demyelinating cascade.  相似文献   
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Summary The objective of this study was to establish a cryopreservation protocol for sour orange (Citrus aurantium L.). Cryopreservation was carried out via encapsulation-dehydration, vitrification, and encapsulation-vitrification on shoot tips excised from in vitro cultures. Results indicated that a maximum of 83% survival and 47% regrowth of encapsulated-dehydrated and cryopreserved shoot tips was obtained with 0.5M sucrose in the preculture medium and further dehydration for 6 h to attain 18% moisture content. Dehydration of encapsulated shoot tips with silica gel for 2h resulted in 93% survival but only 37% regrowth of cryopreserved shoot tips. After preculturing with 0.5M sucrose, 80% of the vitrified cryopreserved shoots survived when 2M sucrose plus 10% dimethyl sulfoxide (DMSO) was used as a cryoprotectant for 20 min at 25°C. Survival and regrowth of vitrified cryopreserved shoot tips were 67% and 43%, respectively, when 0.4M sucrose plus 2M glycerol was used as a loading solution followed by application of 100% plant vitrification solution (PVS2) for 20 min. Increased duration of exposure to the loading solution up to 60 min increased survival (83%) and regrowth (47%) of cryopreserved shoot tips. With encapsulation-vitrification, dehydration with 100% PVS2 for 2 or 3 h at 0°C resulted in 50 or 57% survival and 30 or 40% regrowth, respectively, of cryopreserved shoot tips.  相似文献   
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Abstract

Hexachlorocyclohexane (HCH), a highly chlorinated pesticide, was used worldwide in the 1950s and 1960s. HCH toxic residues are still detected in environmental compartments. Thus, effective, viable and eco-friendly strategy is required for its remediation. In this study, degradation of four HCH isomers was evaluated by amending contaminated soil using four treatments of spent mushroom compost (SMC) of Pleurotus ostraetus. The soil was incubated for 5 weeks and was sampled every seven days. Quantitative attenuation in HCH was calculated using gas chromatography–electron capture detector (GC-ECD) and metabolite was identified using gas chromatography–mass selective detector (GC-MSD). Maximum reduction 58%, 26%, 45%, and 64% for α-, β-, γ- and δ-HCH isomers, respectively, using SMC and soil (both unsterilized) showed that this treatment was the best for bioremediation of HCH in soil. However, when one of the factors, either soil or SMC, was sterilized, a significant reduction in HCH degradation was noticed. The second most reduction of isomers was seen during treatment where unsterilized SMC was added in sterilized soil followed by treatment where SMC was sterilized but soil was not. Abiotic control did not remove any significant quantities of HCH. Simple first-order (SFO) kinetic confirmed that SMC reduced the half-live manifolds as compared to biotic control. Only one metabolite δ-PCCH was identified during the course of study.  相似文献   
70.
Analysis of type 1 metallothionein cDNAs in Vicia faba   总被引:7,自引:0,他引:7  
  相似文献   
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