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Infective Agents (infective + agent)
Selected AbstractsImmune-mediated alteration in gut physiology and its role in host defence in nematode infectionPARASITE IMMUNOLOGY, Issue 8-9 2004W. I. Khan SUMMARY Activation of the mucosal immune system of the gastrointestinal tract in nematode infection results in altered intestinal physiology, which includes changes in intestinal motility and mucus production. These changes are considered to be under direct immunological control rather than a non-specific consequence of the inflammatory reaction to the infective agent. However, little is known about the immunological basis for the changes in intestinal physiology accompanying nematode infection, or the precise role of these changes in host defence, which remains an important area to explore. In this review we describe the mechanisms by which the immune response to nematode infection influences the changes in two major cells of intestinal physiology, namely smooth muscle and goblet cells, and how these changes in intestinal physiology contribute to the host defence. Data clearly demonstrate that the T helper (Th) 2 type immune response generated by nematode infection plays an important role in the development of infection-induced intestinal muscle hypercontractility and goblet cell hyperplasia and that these immune-mediated changes in intestinal physiology are associated with worm expulsion. These observations strongly suggest that intestinal muscle contractility, goblet cell hyperplasia and worm expulsion share a common immunological basis and may be causally related. These data not only provide insights into host defence in nematode infection in the context of muscle function and goblet cell response, but also have broad implications in elucidating the pathophysiology of a wide range of gastrointestinal disorders associated with altered gut physiology. [source] Lack of association between HLA genotype and chronic fatigue syndromeINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 3 2001J. A. Underhill Summary Although the aetiology of chronic fatigue syndrome is controversial, evidence that infective agents including viruses may have a role in the development of the condition has led to studies seeking an association with the immunomodulatory HLA genes. In the present study, we sought to extend previous work using a well-characterized patient group and modern HLA genotyping techniques. Fifty-eight patients were phenotyped for HLA A and B by microcytotoxicity and genotyped for HLA DRB, DQB and DPB by PCR oligoprobing, and the frequencies of antigens so assigned were compared with those from a control group of 134. No significant differences in HLA frequencies were found between patient and control groups. Thus, this study does not confirm previous findings of an HLA association with chronic fatigue syndrome, suggesting that neither presentation of viral antigen by HLA class I nor antigen processing genes in the HLA region is a major contributory factor in the development of the disease. [source] Pathological and epidemiological observations on rickettsiosis in cultured sea bass (Dicentrarchus labrax L.) from GreeceJOURNAL OF APPLIED ICHTHYOLOGY, Issue 6 2004F. Athanassopoulou Summary A systemic infection of a Rickettsia -like organism (RLO) in cultured sea bass is described for the first time. In hatcheries, clinical signs were lethargy, inappetence and discoloration. Twenty days after transfer to sea cages from hatcheries where the disease existed, fish showed erratic and abnormal swimming behaviour, loss of orientation, and lethargy. Cumulative mortality in colder months of the year reached 30% in hatcheries and 80% in cages. Surviving fish in cages did not show any clinical signs of RLO infection in the subsequent year. Evidence for a systemic distribution of RLO was supported by histolopathological lesions in both infected hatchery and caged fish, where the lesion profile included cranial sensory, central nervous, integumental and alimentary organ systems. Intracranial lesions were primarily characterized by an ascending histiocytic perineuritis and necrotizing congestive meningoencephalitis, with evidence for transfer of infective agents across the blood,brain barrier confirmed by the presence of RLOs within capillary endothelium and histiocytes in inflamed regions of the optic tectum and the cerebellum. In the most severe cases, infection spread to the statoacoustical (semicircular) canal system and the ependymal lining of ventricles, with marked rickettsial-laden histiocytic infiltration of the canal lumen. Integumental lesions were restricted to the oral submucosa, nares and integumental dermis of the cranium. Alimentary lesions were noted in both the liver parenchyma and mucosa/submucosa of the stomach. In all affected organs the RLOs were found by immunohistochemistry to be related to Piscirickettsia salmonis. [source] An evaluation of the hand and nasal flora of Turkish nursing students after clinical practiceJOURNAL OF CLINICAL NURSING, Issue 3 2009Reva Balc Aim., The purpose of this study was to evaluate and compare the hand and nasal flora of nursing students before and after the clinical practice. Background., Hospitals are places where infective agents abound. Healthcare workers, relatives of patients and students practising in the hospital medium are often exposed to these infective agents. Although the role of the hand and nasal flora of healthcare workers in the development of nosocomial infections has been emphasised by earlier studies, there are a limited number of studies which investigate the hand and nasal flora of nursing students. Design., Descriptive. Methods., This descriptive study involved 66 volunteer nursing students. Two samples of flora from both hands and nose of each student were obtained. The inoculated samples were then evaluated through routine bacteriological study methods. Chi-square and percentage calculations were used in comparisons. Results., None of the students had methicillin-resistant Staphylococcus aureus or methicillin-resistant coagulase-negative Staphylococcus colonisation in the hand samples before clinical practice, 6·1% of the students had methicillin-resistant Staphylococcus aureus and 4·5% had methicillin-resistant coagulase-negative Staphylococcus colonisation after the practice. Although the differences between the rates of contamination with pathogen micro-organisms in the hand and nasal flora of the student nurses before and after clinical practice were not significant, the rate of colonisation after clinical practice was higher. Conclusions., In this study, the rate of colonisation after clinical practice was higher. These findings indicate that students might have been contaminated with bacteria during clinical practice. Relevance to clinical practice., The results of this study have practical importance in clinical practice. The role of the hand and nasal flora of nursing students in the development of nosocomial infections is significant. For this reason, some precautions, such as using gloves and handwashing with special solutions when needed, should be taken to prevent nosocomial infections and protect students against associated risks. [source] Clinical characteristics and outcome analysis of pediatric B-cell non-Hodgkin's lymphoma.ASIA-PACIFIC JOURNAL OF CLINICAL ONCOLOGY, Issue 1 2010Experience with FAB-LMB 9, UKCCSG B-cell NHL guidelines in a developing country Abstract Aim: To analyze the clinical characteristics of B-cell non-Hodgkin's lymphoma (NHL) patients and the therapeutic efficacy of French-American-British Lymphoma Malins de Burkitt 96 and the recent United Kingdom Children's Cancer Study Group B-cell NHL guidelines in the tertiary care hospital of a developing country. Methods: Patients aged ,18 years registered at our hospital between January 1995 and December 2006 with histologically proved B-Cell NHL were selected for retrospective analysis. Results: Of the total of 131 patients registered, 122 patients were eligible for evaluation. Of these 95 had Burkitt's lymphoma, 22 diffuse large B-cell lymphoma and five had B-cell NHL not otherwise specified. The mean age was 8.4 years. Overall 42 children had a baseline weight less than the 10th centile. A total of 37 had uric acid >10 mg/dl and 55 had a lactate dehydrogenase level >500; 73 had stage III and 31 had stage IV while only four presented at stage I and 14 at stage II. The abdomen was the commonest site of disease. A total of 45 patients died; 28 due to infection, nine due to tumor lysis syndrome and six of uncontrolled disease. All deaths occurred within an average of 35 days from starting treatment. Our 5-year overall survival rate was 68 percent and our event-free survival was 55 percent. Conclusion: Late presentation with advanced disease, poor nutritional status and high risk of exposure to infective agents all contribute to the high mortality in patients treated with intensive protocols in resource-poor countries. [source] | ||||||||||