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The study of depressive symptoms among caregivers raising HIV/AIDS-orphans is emerging as an important area of research. However, it has not been explored at length in generational and cultural contexts. In this study, the authors explore the role of financial strain, raising a HIV-infected and/or impacted child, and caregiver knowledge on the depressive symptoms of 89-older caregivers raising HIV/AIDS-orphans in Namibia, Africa. In this study, we found elevated levels of depressive symptoms among this population. Using hierarchical regression, a significant positive association between financial strain and depressive symptoms was found. A significant negative association between caring for an HIV-infected orphan and depression was shown. Our work suggests the need for economic assistance programs and psychosocial interventions for older caregivers.  相似文献   
33.
We evaluated whether isoflurane, halothane and sevoflurane attenuate the inflammatory response and improve lung morphofunction in experimental asthma. Fifty‐six BALB/c mice were sensitised and challenged with ovalbumin and anaesthetised with isoflurane, halothane, sevoflurane or pentobarbital sodium for one hour. Lung mechanics and histology were evaluated. Gene expression of pro‐inflammatory (tumour necrosis factor‐α), pro‐fibrogenic (transforming growth factor‐β) and pro‐angiogenic (vascular endothelial growth factor) mediators, as well as oxidative process modulators, were analysed. These modulators included nuclear factor erythroid‐2 related factor 2, sirtuin, catalase and glutathione peroxidase. Isoflurane, halothane and sevoflurane reduced airway resistance, static lung elastance and atelectasis when compared with pentobarbital sodium. Sevoflurane minimised bronchoconstriction and cell infiltration, and decreased tumour necrosis factor‐α, transforming growth factor‐β, vascular endothelial growth factor, sirtuin, catalase and glutathione peroxidase, while increasing nuclear factor erythroid‐2‐related factor 2 expression. Sevoflurane down‐regulated inflammatory, fibrogenic and angiogenic mediators, and modulated oxidant–antioxidant imbalance, improving lung function in this model of asthma.  相似文献   
34.
Having an advisor offers medical students many advantages, including increased likelihood of matching into their top choices. Interestingly, students who choose emergency medicine (EM) as a specialty are more likely to seek advising. However, finding and optimally utilizing an EM faculty advisor is often challenging for the medical student. In this article, we tackle the different ways to seek advising, including the ‘virtual advisor program’ implemented by the Society for Academic Emergency Medicine, the ‘e-Advisor Program’ instigated by the Clerkship Director in EM Group, the ‘member exclusive mentorship program’ of the Emergency Medicine Residency Association, as well as peer-based mentoring. More so, we discuss the consensus recommendations developed by the Student Advising Task Force to guide both students planning to apply to EM and their advisors to ensure high-caliber advising.  相似文献   
35.
Maturity-Onset Diabetes of the Young type 4 is a rare form of diabetes mellitus, caused by mutations in the PDX1 gene. However, only a few mutations in this gene have been associated as a cause of monogenic diabetes up to date. It makes difficult to create a clinical manifestation profile of this disease and, consequently, to improve the therapeutic management for these patients. Here we report a normal weight woman, diagnosed with diabetes mellitus at 27 years old, during her first pregnancy. At the time of the recruitment, she was 40 years old and had a body mass index of 23.9 kg/m2, glycated hemoglobin level of 9.6%, and fasting plasma glucose (FPG) of 254 mg/dL. She presented no diabetic complications and she was being treated with insulin. She reported a family history of diabetes mellitus characteristic of an autosomal dominant mode of inheritance. Molecular analysis of the PDX1 gene revealed the missense variant c.532G > A (p.(Glu178Lys)) segregating from the patient to her son, reported as diabetic. It was absent in her healthy daughter. The c.532G > A seems to be a rare variant, absent in human variants databases, and among 86 normoglycemic controls. Eight in silico algorithms classified this variant as probably pathogenic. Additionally, analysis of the evolutionary conservation showed the glutamic acid in the position 178 of PDX-1 protein as conserved among several species. Our findings reinforce the importance of screening rare MODY genes among families with suspicion of monogenic diabetes to help better understand the clinical manifestations of this disease.  相似文献   
36.
The interaction between the human immunodeficiency virus (HIV) integrase (IN) and its cellular cofactor lens epithelium-derived growth factor (LEDGF/p75) is crucial for HIV replication. While recently discovered LEDGINs inhibit HIV-1 replication by occupying the LEDGF/p75 pocket in IN, it remained to be demonstrated whether LEDGF/p75 by itself can be targeted. By phage display we identified cyclic peptides (CPs) as the first LEDGF/p75 ligands that inhibit the LEDGF/p75–IN interaction. The CPs inhibit HIV replication in different cell lines without overt toxicity. In accord with the role of LEDGF/p75 in HIV integration and its inhibition by LEDGINs, CP64, and CP65 block HIV replication primarily by inhibiting the integration step. The CPs retained activity against HIV strains resistant to raltegravir or LEDGINs. Saturation transfer difference (STD) NMR showed residues in CP64 that strongly interact with LEDGF/p75 but not with HIV IN. Mutational analysis identified tryptophan as an important residue responsible for the activity of the peptides. Serial passaging of virus in the presence of CPs did not yield resistant strains. Our work provides proof-of-concept for direct targeting of LEDGF/p75 as novel therapeutic strategy and the CPs thereby serve as scaffold for future development of new HIV therapeutics.  相似文献   
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Tobacco is a major Brazilian cash crop. Tobacco farmers apply large amounts of pesticides to control insect growth. Workers come into contact with green tobacco leaves during the tobacco harvest and absorb nicotine through the skin. In the present study, micronucleus frequency, cell death, and the frequency of basal cells were measured in tobacco farmers using the buccal micronucleus cytome assay (BMCyt), in parallel with measurement of blood butyrylcholinesterase (BChE) and nicotine levels. Polymorphisms in PONIGln192Arg and CYP2A6*9(?48T>G) were evaluated to verify the relationship between genetic susceptibility and the measured biomarkers. Peripheral blood and buccal cell samples were collected from 106 agricultural workers, at two different crop times (during pesticide application and leaf harvest), as well as 53 unexposed controls. BMCyt showed statistically significant increases in micronuclei, nuclear buds, and binucleated cells among exposed subjects in differentiated cells, and in micronuclei in basal cells. In addition, the exposed group showed higher values for condensed chromatin, karyorrhectic, pyknotic, and karyolitic cells, indicative of cell death, and an increase in the frequency of basal cells compared to the unexposed control group. A slight difference in mutagenicity using the BMCyt assay was found between the two different sampling times (pesticide application and leaf harvest), with higher micronucleus frequencies during pesticide application. Elevated cotinine levels were observed during the leaf harvest compared to the unexposed controls, while BChE level was similar among the farmers and controls. PONIGln192Arg and CYP2A6*9(?48T>G) polymorphisms were associated with DNA damage induced by pesticides and cell death. Environ. Mol. Mutagen., 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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40.

ABSTRACT

BACKGROUND/PURPOSE

Previous imaging studies in the Machado‐Joseph disease (MJD/SCA3) have mostly concentrated on the cerebellum and brainstem. Our goal was to perform a whole brain longitudinal evaluation.

METHODS

We included 45 patients and 51 controls, who underwent two brain magnetic resonance imaging and magnetic resonance spectroscopy (mean interval of 12.5 ± 1.5 months). We used voxel‐based morphometry (VBM) and the MarsBar analysis toolbox to extract grey matter density (GMD) values from regions of interest. We used a linear regression model and a general linear model to correlate GMD with clinical markers, and paired t‐test for the longitudinal evaluation.

RESULTS

We observed decreased GMD (P < .01) at frontal, parietal, temporal and occipital lobes, subcortical grey matter, cerebellum, and brainstem. White matter atrophy was restricted to the cerebellum. Age, CAG, and disease duration predicted GMD in different areas, but age and CAG were the most important predictors. The longitudinal analysis failed to demonstrate changes. Changes in regions other than the cerebellum appeared to contribute significantly to the final International Cooperative Ataxia Rating Scale score.

CONCLUSION

We confirmed cortical involvement in MJD/SCA3. The most important factors in predicting GMD were age and CAG. The lack of progression of atrophy may indicate floor effect and/or short duration of follow‐up.  相似文献   
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