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Nand L. Sharma Vikram K. Mahajan Neelam Gupta Nitin Ranjan and Anju Lath 《Journal of cutaneous pathology》2009,36(4):486-492
Ehlers-Danlos syndrome – vascular type, the only lethal form, is rarely reported in dermatology literature. It is characterized by translucent, atrophic skin, easy bruising, arterial, intestinal and/or uterine fragility manifesting as varicose veins, aneurysms and vascular/visceral/uterine rupture. As its dermatopathologic features are not well elucidated, diagnosis is often made after a catastrophic complication or at autopsy. This 36 year-old non-consanguineous male had brown-black plaques with atrophy and frequent ulceration over legs and dorsal feet and tortuous varicose veins around ankles for the past 15 years. Perivenous skin was translucent and hypopigmented. He had multiple and ecchymotic keloids and small atrophic, pityriasis versicolor-like lesions over trunk. He did not have hypermobile/hyperextensible skin and joints and showed no systemic or investigative abnormality. Histopathologic features of atrophic lesion included blood extravasation in atrophic epidermis/dermis, focal clustering and dilatation of blood vessels, malformed vessel walls, abundant hemosiderin in the dermis and homogenously stained/whorled patterned collagen especially around blood vessels. Pathology of keloidal lesion showed new collagen and vascular fragility. These histopathologic features appear of diagnostic value especially in patients who have compatible clinical findings but cannot afford confirmation by biochemical testing for abnormal synthesis of type III procollagen or identification of mutations in the COL3A1 gene. 相似文献
3.
Ashwin A Kallianpur Rajinder Parshad Maya Dehran Priya Hazrah 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(2):229-234
BACKGROUND AND OBJECTIVES: Feasibility of ambulatory laparoscopic inguinal hernia repair in developing countries is not known due to lack of dedicated outpatient centers. This study prospectively evaluated the feasibility of outpatient discharge after laparoscopic total extraperitoneal inguinal hernia repair done in combination with in-hospital services and its impact on quality of life. METHODS: Forty patients were studied who had uncomplicated inguinal hernias and fulfilled the selection criteria. Quality of life was evaluated by using the SF-12 questionnaire. RESULTS: Ninety percent of patients could be discharged as outpatients. Four patients required admission. No major complications or readmissions occurred. Physical components of quality of life deteriorated in the immediate postoperative period but improved to above preoperative levels within one month. A transient deterioration in subgroups of the mental health component was observed, which recovered to normal in less than a week. There was no significant alteration in the emotional component. There has been no recurrence at a median follow-up of 25 months. CONCLUSION: It was feasible to safely perform outpatient TEP in combination with routine in-hospital services without increasing complications or causing any adverse impact on quality of life. This was possible subject to adherence to proper selection and discharge criteria. 相似文献
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An out line of the scheme of training specialists in Otorhinolaryngology-Head and Neck Surgery (ORL-HNS) in South Africa is
given and the difference with Indian training discussed 相似文献
6.
Regulation of immunoglobulin heavy-chain gene rearrangements 总被引:1,自引:0,他引:1
Summary: Regulated assembly of antigen receptor gene segments to produce functional genes is a hallmark of B‐ and T‐lymphocyte development. The immunoglobulin heavy‐chain (IgH) and T‐cell receptor β‐chain genes rearrange first in B and T lineages, respectively. Both loci require two recombination events to assemble functional genes; D‐to‐J recombination occurs first followed by V‐to‐DJ recombination. Despite similarities in overall rearrangement patterns, each locus has unique regulatory features. Here, we review the characteristics of IgH gene rearrangements such as developmental timing, deletion versus inversion, DH gene segment utilization, ordered recombination of VH gene segments, and feedback inhibition of rearrangement in pre‐B cells. We summarize chromatin structural features of the locus before and during recombination and, wherever possible, incorporate these into working hypotheses for understanding regulation of IgH gene recombination. The picture emerges that the IgH locus is activated in discrete, independently regulated domains. A domain encompassing DH and JH gene segments is activated first, within which recombination is initiated. VH genes are activated subsequently and, in part, by interleukin‐7. These observations lead to a model for feedback inhibition of IgH rearrangements. 相似文献
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Polyglutamine diseases consist of a group of familial neurodegenerative disorders caused by expression of proteins containing expanded polyglutamine stretch. Over the past several years, tremendous progress has been made in identifying the molecular mechanisms by which the expanded polyglutamine tract leads to neuronal dysfunction and neurodegeneration. A common feature of most polyglutamine disorders is the occurrence of ubiquitin-positive neuronal intranuclear inclusions. The appearance of ubiquitinated aggregates implies an underline incapability of the cellular chaperones and proteasome machinery that normally functions to prevent the accumulation of misfolded proteins. Here we review the recent studies that have revealed a critical role for molecular chaperones and ubiquitin-proteasome pathway in the pathogenesis of polyglutamine diseases. 相似文献
9.
Listeria--review of epidemiology and pathogenesis. 总被引:2,自引:0,他引:2
Vidhya Ramaswamy Vincent Mary Cresence Jayan S Rejitha Mohandas Usha Lekshmi K S Dharsana Suryaprasad Priya Prasad Helan Mary Vijila 《Journal of microbiology, immunology, and infection》2007,40(1):4-13
Listeria monocytogenes (commonly called Listeria) is a Gram-positive facultatively intracellular foodborne pathogen often found in food and elsewhere in nature. It can cause a rare but serious disease called listeriosis, especially among pregnant women, the elderly or individuals with a weakened immune system. In serious cases, it can lead to brain infection and even death. Listeria is more likely to cause death than other bacteria that cause food poisoning. In fact, 20 to 30% of food borne listeriosis infections in high-risk individuals may be fatal. Recent technological developments have increased the ability of scientists to identify the cause of foodborne illnesses. L. monocytogenes has been used as a model organism for the study of intracellular parasitism. Whilst the basic mechanisms of cellular pathogenesis have been elucidated by a series of elegant studies, recent research has begun to focus upon the gastrointestinal phase of L. monocytogenes infection. Epidemiological studies of outbreaks of human disease now demonstrate that the pathogen can cause gastroenteritis in the absence of invasive disease and associated mortality. Elucidation of whole genome sequences and virulence determinants have greatly contributed to understanding of the organism and its infection pathways. 相似文献
10.
BACKGROUND: Apart from traditional markers studied among a few numerically small, geographically defined surveys among Mongoloid populations in northeastern parts of India, very little is known about their genomic diversity at the molecular level. PRIMARY OBJECTIVE: This study seeks to investigate how best the variable number tandem repeat (VNTR) and short tandem repeat (STR) loci together can detect the patterns of the genetic affinity among five geographically contiguous, linguistically and socio-culturally diverse Mongoloid-affiliated populations of Manipur in northeastern regions of India. SUBJECT AND METHODS: Blood samples were collected from unrelated and randomly selected volunteers of five ethnic populations (Meitei, Kuki, Naga, Hmar and Manipuri Muslim) from different parts of the state. Allelic variation in four minisatellite loci (D1S7, D4S139, D5S110 and D17S79) and three STR loci (vWA, FESFPS and F13AO1) was studied. RESULTS: Average heterozygosity values among the five groups for the minisatellite range from 68% to 94%, while the hypervariable three STR loci were between 60% and 88%. In the populations, all the studied loci were highly polymorphic, with almost no departure from Hardy-Weinberg equilibrium. The gene differentiation for the VNTR loci was lower and moderate (G(st) = 0.030) in comparison with microsatellites (G(st) = 0.043). The neighbour-joining method of clustering based on both type of molecular markers reveals a close cluster for the tribal groups of Kuki, Naga and Hmar, while Manipur Muslim stand distinct in both the trees. The clustering pattern obtained from the combined DNA marker loci matches more closely the pattern from STR loci than that obtained from VNTR loci. CONCLUSIONS: The results reinforce that using both VNTR and STR loci in detecting regional genetic affinity among the populations is more effective than using VNTR or STR independently, and also confirm the results obtained from the serological and electrophoretic data. However, the clustering pattern obtained from combined DNA markers is more in conformity with the pattern obtained by STR loci rather than with VNTR loci. Despite linguistic, geographical and cultural barriers, the populations show genetic affinity among the four populations except in the case of the migrant Manipur Muslim group. 相似文献