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The skin is an important tissue of the immune system; however, little is known about immune cells in dolphin skin, and very few cetacean-specific immunoreagents are available for investigative purposes. Therefore, in this study immunohistochemistry techniques were used with species-specific and non-species-specific antibodies to characterize immune cells, primarily focusing on Langerhans cells, in skin from the Atlantic bottlenose dolphin (Tursiops truncatus). An antibody to human major histocompatibility complex (MHC) class II molecules labeled cells with a dendritic-like morphology. The immunophenotype, morphology, and distribution of some of these cells are consistent with those of Langerhans cells. The cells were predominantly found in dermal papillae, primarily along the epidermal-dermal junction. Thus, the location of these cells was somewhat different from that in terrestrial mammals. Other MHC II (+) cells of varying morphology were observed deeper in the dermis, with a perivascular concentration, and had characteristics of macrophages and dermal dendritic cells. There was no immunostaining with cetacean-specific CD2 or CD21. In diseased skin, a subjective increase of MHC II (+) cells, most notably in the superficial skin layers, was associated with an ulcerative dermatitis. A few CD2 (+) cells were also present. Differences between dolphins and terrestrial mammals in terms of morphology, mechanisms of response to insult and repair, and environmental challenges may explain the modified distribution of MHC II (+) cells in dolphin skin. An elucidation of the immune cells in cetacean skin will contribute to our understanding of the evolution of functional adaptations to various environments, facilitate diagnosis of skin diseases, and define the potential for intradermal administration of vaccines and other immunotherapeutics.  相似文献   
43.
Self-report screening measures for depression in chronic pain patients   总被引:3,自引:0,他引:3  
Depression is prevalent among chronic pain patients, yet little is known about the ability of various self-report measures to detect this disorder in this population. This study investigated the relationship of several self-report depression scales (Beck Depression Inventory-standard and short forms, MMPI Depression, Depression subtle, and Depression obvious scales, and the Zung Self-Rating Depression Scale) to clinician DSM-III diagnoses of major depressive disorder in 40 chronic pain patients. Thirty percent of the Ss met criteria for major depression. Sensitivity and specificity values obtained for each scale are presented. The standard and short forms of the Beck Depression Inventory and the Zung Self-Rating Depression Scale showed good sensitivity and specificity and were comparable in detecting major depression in this sample.  相似文献   
44.
Incubation of trinitrophenylated hemocyanin (TNP-KLH)-primed spleen cells with microgram amounts of 2,4-dinitrophenyl (DNP) or 2,4,6-trinitrophenyl (TNP) conjugates of pneumococcal polysaccharide type 3 (SIII) for as little as 5 min at 4 degrees C results in a specific "block" of the 19 S and 7 S adoptive memory response to TNP-KLH. This hapten-SIII-induced block of anti-hapten memory B cell responsiveness seems to be an example of specific receptor blockade.The block is specific and can be prevented by simultaneous incubation of the primed cells with hapten-protein conjugates which presumably compete with the hapten-polysaccharide for attachment to the B cell surface via anti-hapten Ig receptors. Removal via capping of these Ig receptors by exposure of TNP-KLH-primed memory cells to rabbit anti-mouse Fab serum for 45 min at 37 degrees C renders these cells refractory to the blocking effect of hapten-SIII. Once the hapten-SIII has attached to the memory cells, these blocked cells can be "rescued" (i.e. returned to a state of responsiveness) by incubating these cells with either mouse anti-SIII at 37 degrees C or rabbit anti-DNP serum at 4 degrees C. Since a papain digest of the IgG fraction of rabbit anti-DNP did not rescue the cells while the intact IgG did, a capping off of the TNP-SIII was proposed as the mechanims for this return to responsiveness of the hitherto blocked cells. A rescue was not seen by treatment of recipient mice with such B cell mitogens as dextran sulfate, endotoxin or purified protein derivative of tuberculin.  相似文献   
45.
We report on mosaic 46,XY/46,XY,del(5)(p15) cri du chat syndrome. The clinical findings are compared with those compiled from a literature survey. A phoniatric evaluation was performed and compared with that of a cri du chat patient without mosaicism previously observed by the authors.  相似文献   
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T cell function is altered in vivo and in vitro in elderly compared with young subjects, and this alteration is believed to contribute to morbidity and mortality in man due to the greater incidence of infection, as well as autoimmunity and cancer in elderly. The majority of T cells express TCRalphabeta whereas TCRgammadelta is expressed on a minority of T cells. Moreover, it is known that gammadelta T lymphocytes display major histocompatibility complex (MHC)- unrestricted cytotoxicity that is reminiscent of natural killer (NK) activity. In view of earlier findings on both T cells and NK cells in the elderly, we hypothesised a different behaviour of gammadelta T lymphocytes from old subjects when compared with gammadelta T lymphocytes obtained from young people. Therefore, to gain further insight into mechanisms of immunosenescence in this little-studied population, we studied immunofluorescence analysis gammadelta T cells from the elderly. Our preliminary results show that the percentage of blood gammadelta T cells in lymphocytes from old subjects is decreased when compared with the young. Interestingly, these cells are more activated in the elderly than in young subjects; expression of CD69, an early activation marker, is increased in gammadelta T lymphocytes from old subjects after three hours of in vitro culture both with and without lipopolysaccharide stimulation. Thus, our findings, which need confirmation, strongly suggest that, in humans, gammadelta T cells are early responders when compared with alphabeta T cells. They may act as 'first aid' cells to replace the described deficit of the specific and aspecific immunity in elderly. In this view, the proinflammatory status, observable in the elderly, renders them ready to be stimulated by exogenous agents.  相似文献   
49.
Unilateral obstruction of a duplicate uterus is very rare. The current recommendation for its correction involves transmural incision of the uterine muscle. A method is presented here that was successfully applied in one patient suffering from this anomaly, using sonographically guided hysteroscopy. This method obviated the need for an extensive operation.  相似文献   
50.
Lexical priming deficits as a function of age   总被引:2,自引:0,他引:2  
The effects of age on implicit memory were assessed in elderly young adults using 2 priming procedures. Subjects also completed the WAIS-R, 3 tests to assess frontal lobe function, and 2 recall and 2 recognition tests of explicit memory. In Experiment 1, subjects were exposed to the low-frequency member of a homophone pair in a test purported to assess general knowledge. Subsequently, subjects completed a spelling test that contained the previously presented homophones to assess priming. Young subjects demonstrated priming (p less than .01). Elderly subjects demonstrated a high baseline that may have obscured priming. In Experiment 2, subjects from each decade of life from the 20s through the 80s were given a word-stem completion test of priming. All age conditions demonstrated an effect of priming (p less than .01). However, subjects in their 70s and 80s demonstrated lower priming scores (p less than .05). Elderly subjects were also impaired on immediate-and delayed-recall tests. These results suggest an age-related decline in both implicit and explicit memory.  相似文献   
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