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Growing problem of methicillin resistant staphylococci--Indian scenario   总被引:1,自引:0,他引:1  
In the present study MRSA prevalence increased from 12% in 1992 to 80.83% in 1999. Indian literature shows that MRSA incidence was as low as 6.9% in 1988 and reached to 24% and 32.6% in Vellore and Lucknow in 1994 and was of the same order in Mumbai, Delhi and Bangalore in 1996 and in Rohtak and Mangalore in 1999. However, in some of the centres it was as high as 87%. All the MRSA isolates in India including in the present study were sensitive to vancomycin and resistance to netilmycin appears to be low among MRSA isolates in India. All the MRSA isolates were also found to be sensitive to teicoplanin in the present study. Like in other Indian studies, resistance to cotrimoxazole, erythromycin, gentamicin, other penicillins and cephalosporins appeared to be a common feature for MRSA isolates in the present study.  相似文献   
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The macrophage migration inhibitory factor (MIF) is a potent pro-inflammatory cytokine and regulates the anti-inflammator effects of glucocorticoids. An important role for MIF within the cytokine cascade is to act in concert with endogenous glucocorticoids to control the set-point and magnitude of the inflammatory response. Elevated expression of MIF in the circulation and in the synovial joint has been documented in rheumatoid arthritis. MIF also has been linked to the development of joint damage and disease pathology in experimental animal models. We describe herein a novel CATT-tetranucleotide repeat polymorphism at position -794 of the human Mif gene and show that it functionally affects the activity of the MIF promoter in gene reporter assays. We describe four genotypes which comprise 5, 6, 7, or 8-CATT repeat units and show that the 5-CATT allele has the lowest level of basal and stimulated MIF promoter activity in vitro. The presence of the low expressing, 5-CATT repeat allele correlated with low disease severity in a cohort of rheumatoid arthritis patients.  相似文献   
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Erythrocyte invasion by Plasmodium vivax is completely dependent on binding to the Duffy blood group antigen by the parasite Duffy binding protein (DBP). The receptor-binding domain of this protein lies within a cysteine-rich region referred to as region II (DBPII). To examine whether antibody responses to DBP correlate with age-acquired immunity to P. vivax, antibodies to recombinant DBP (rDBP) were measured in 551 individuals residing in a village endemic for P. vivax in Papua New Guinea, and linear epitopes mapped in the critical binding region of DBPII. Antibody levels to rDBP(II) increased with age. Four dominant linear epitopes were identified, and the number of linear epitopes recognized by semi-immune individuals increased with age, suggesting greater recognition with repeated infection. Some individuals had antibodies to rDBP(II) but not to the linear epitopes, indicating the presence of conformational epitopes. This occurred in younger individuals or subjects acutely infected for the first time with P. vivax, indicating that repeated infection is required for recognition of linear epitopes. All four dominant B-cell epitopes contained polymorphic residues, three of which showed variant-specific serologic responses in over 10% of subjects examined. In conclusion, these results demonstrate age-dependent and variant-specific antibody responses to DBPII and implicate this molecule in partial acquired immunity to P. vivax in populations in endemic areas.  相似文献   
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Structural brain abnormalities are consistently reported in schizophrenic subjects but the etiology of these abnormalities remains unclear. We tested the contribution of genetic predisposition and obstetric complications to the structural brain abnormalities found in schizophrenic probands and their relatives. MRI scans were carried out on 35 schizophrenic probands from families multiply affected with the disorder, and 63 of their unaffected relatives, including 10 parents who appeared to transmit genetic risk to their children; as well as 31 schizophrenic probands from families with no other affected members, 33 of their unaffected relatives; and finally 68 controls. Volumetric measurements of whole brain, lateral ventricles, third ventricle, cerebellum, and temporal lobes were completed for each subject. The impact of obstetric complications on brain structure was assessed across the gradient of presumed genetic predisposition. Both groups of schizophrenic probands displayed enlargement of the lateral and third ventricles, and there was a gradient of ventricular enlargement amongst the unaffected relatives in proportion to their likelihood of carrying schizophrenic genes. Ventricular enlargement was largely confined to males in both probands and unaffected relatives. Obstetric complications were associated with ventricular enlargement only in the familial probands. Non-familial probands displayed reduced volume of the temporal lobes bilaterally. In families with several schizophrenic members, ventricular enlargement is a marker for genetic liability, particularly in males. Individuals inheriting the susceptibility to schizophrenia appear particularly prone to develop ventricular enlargement in response to obstetric complications.  相似文献   
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Pathology, microbiology, blood bank and other diagnostic laboratories generate sizable amount of biomedical waste (BMW). The audit of the BMW is required for planning proper strategies. The audit in our laboratory revealed 8 kgs anatomical waste, 600 kgs microbiology waste, 220 kgs waste sharps, 15 kgs soiled waste, 111 kgs solid waste, 480 litres liquid waste along with 33,000 litres per month liquid waste generated from labware washing and laboratory cleaning and 162 litres of chemical waste per month. Section wise details are described in the text. Needle sharps are collected in puncture proof containers and the needles autoclaved before sending to needle pit. The glass forms the major sharp category and is disinfected with hypochlorite before washing/recycling. All microbiology waste along with containers/plates/tubes are autoclaved before recycling/disposal. The problem of formalin fixed anatomical waste as histology specimens is pointed out. The formalin containing tissues cannot be sent for incineration for the fear of toxic gas release and the guidelines by the Biomedical waste rule makers need to be amended for the issue. The discarded/infected blood units in blood bank need to be autoclaved before disposal since chemical treatments are difficult or inefficient. The liquid waste management needs more attention and effluent treatment facility needs to be viewed seriously for hospital in general. The segregation of waste at source is the key step and reduction, reuse and recycling should be considered in proper perspectives.  相似文献   
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OBJECTIVE: Structural magnetic resonance imaging (MRI) studies that focus on first-episode psychosis avoid some common confounds, such as chronicity of illness, treatment effects, and long-term substance abuse. However, such studies may select subjects with poor short-term treatment response or outcome. In this study, the authors focus on structural brain abnormalities in never or minimally treated patients who underwent MRI scanning early in their first episode of psychosis. METHOD: The authors examined 37 patients (13 medication naive, 24 previously treated) who were experiencing their first episode of psychosis; the mean duration of symptoms was short (31 weeks). These patients were comparable in age, gender, handedness, ethnicity, and parental socioeconomic status to a group of 25 healthy comparison subjects. A three-dimensional, inversion recovery prepared, fast spoiled gradient/recall in the steady state scan of the whole brain that used 1.5-mm contiguous sections was performed to acquire a T(1)-weighted data set. Human ratings of volumetric measurement of brain structures were performed with stereological techniques on three-dimensional reconstructed MRIs. RESULTS: The patient group had significant deficits in cortical gray matter, temporal lobe gray matter, and whole brain volume as well as significant enlargement of the lateral and third ventricles. Structural deviations were found in both treatment-naive and minimally treated subjects. No relationships were found between any brain matter volumes and positive or negative symptoms. CONCLUSIONS: Structural brain abnormalities were distributed throughout the cortex with particular decrement evident in gray matter. This feature is consistent with altered cell structure and disturbed neuronal connectivity, which accounts for the functional abnormality of psychosis.  相似文献   
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