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32.
BACKGROUND: Otsuka Long-Evans Tokushima Fatty (OLETF) rats genetically develop diabetes which is associated with hypertension. In preliminary studies, urinary excretions of L-PGDS (lipocaline-type prostaglandin D synthase) increase before diabetic nephropathy obviously develops, and this may predict progression of renal injury following diabetes. In the present study, we attempted to define whether urinary excretions of L-PGDS behave as the predictor of development of diabetic nephropathy in OLETF rats. METHODS: We investigated alterations of urinary L-PGDS excretions during the establishment of diabetes and assessed the relationship between the L-PGDS excretions and renal function in OLETF rats. Furthermore, we treated OLETF rats with troglitazone and analysed the effects on L-PGDS metabolisms. Urinary L-PGDS was measured by immunoenzyme assay and the occurrence of L-PGDS and its mRNA in the kidney was assessed by immunohistochemistry and a PCR method. RESULTS: Urinary excretions of L-PGDS were significantly higher in OLETF rats than non-diabetic Long-Evans Tokushima Otsuka (LETO) rats. The excretions age-dependently increased in OLETF and this increase appeared to be due to increased glomerular permeability to L-PGDS. Messenger RNA and antigenicity of L-PGDS were demonstrated in renal tissue; however, the de novo synthesis of L-PGDS mRNA seemingly contributed to urinary L-PGDS excretions much less than glomerular filtration. Multiple regression analysis revealed that urinary L-PGDS was determined by urinary protein excretions, and not by high blood pressure per se. Conversely, urinary proteinuria in the established diabetic nephropathy was predicted by urinary L-PGDS excretions in the early stage of diabetes. CONCLUSIONS: Urinary excretions of L-PGDS are likely to reflect the underlying increase in glomerular permeability. This property may be useful to predict forthcoming glomerular damage following diabetes in OLETF rats.  相似文献   
33.
Preliminary evaluation of the processes of changing to a low-fat diet   总被引:3,自引:2,他引:1  
The purpose of the present paper is to identify the processesof changing dietary fat consumption using Prochaska's transtheoreticalmodel. This model assigns individuals into a series of stages,emphasizing the cognitive, social and behavioral steps of change.At each of the stages an individual focuses on different processes,or coping strategies, to enable movement to the next stage.Dietary process items were created by a multidisciplinary teamusing the smoking processes as a model. These items were subjectedto a Q-sort and piloted in convenience samples. The processitems were distributed with staging questionnaires to 720 membersof an outdoor folk music festival audience. The final groupof 121 process items was subjected to exploratory factor analysisof principle components with varimax rotation. Eight independentfactors emerged during this factor analysis. The processes measuredby the final 60-item questionnaire relate to the stages of changein the hypothesized manner. Applications of this model to interventionsettings seem possible.  相似文献   
34.
Summary Human peripheral blood mononuclear cells (PBMC) from two individuals experimentally and one naturally infected withGiardia lamblia responded strongly (in anin vitro lymphocyte proliferation assay) to both heterologous and homologous (parasite origin)G. lamblia antigen stimuli. Proliferative responses to specific antigens as determined by T-cell blotting were due toGiardia T-cell epitopes mostly present in antigens lower than Mr 85,000 and 31,000 in isolates PM and GS/M-H7, respectively. Additionally, Il-2 production of PBMC respective to T lymphocyte subsets under antigen stimulation were determined in one selected patient. Proliferative and lymphokine responses could be associated with CD4+ PBMC depleted of CD8+ T cells and not with PBMC depleted of CD4+ T cells. These preliminary results suggest the initiation of larger studies addressing questions of cell-mediated immune response and the role of lymphokines in human giardiasis.
Zelluläre Immunreaktion gegen Giardia lamblia beim Menschen
Zusammenfassung Periphere Blutmonozyten von zwei Personen mit einer experimentell und einer mit einer natürlich erworbenenGiardia lamblia-Infektion zeigten eine ausgeprägte lymphoproliferative Antwort nachIn-vitro-Stimulation mit Parasitenantigen, das sowohl aus homologen als auch heterologen Parasitenisolaten gewonnen worden war. Eine T-Zell-Blot- Analyse der lymphoproliferativen Immunantwort bezüglich der nach Molekulargewicht aufgetrenntenGiardia-Antigenkomponenten zeigte, daß das Spektrum derGiardia-Antigene mit T-Zell-Epitopen im Mr-Bereich von < 85'000 für das PM-1-Isolat und < 31'000 für das GS/M-H7-Isolat lagen. Bei einem der Patienten wurden Lymphozyten nach antigen-spezifischerIn-vitro-Proliferation auf ihre Lymphozytensubpopulationen und deren Fähigkeit zur Il-2-Produktion untersucht. Eine lymphoproliferative Antwort, verkoppelt mit einer Il-2-Produktion, war nur bei CD4+ Lymphozyten (nach entsprechender Eliminierung von CD8+ Lymphozyten) und nicht bei CD8+ Lymphozyten (nach entsprechender Eliminierung von CD4+ Lymphozyten) nachweisbar.
  相似文献   
35.
Age at first intercourse for a sample of adult white women using variables measured during childhood is predicted. Childhood predictors were measured at birth, and ages 5 and 9–11, using existing public-use data on the women. Median age at first intercourse for the sample was 17.5 years. Early family predictors, early developmental characteristics, and temperamental characteristics during childhood together could predict about a fourth of the variance in age at first intercourse. The strongest predictors were motor skills and nightmares at age 5, church attendance with family at age 9, and domineering and mature personality at age 9.This research was supported by grants R01-HD23454 and P30-HD05798 from the National Institute of Child Health and Human Development. An earlier version of this paper was presented at the annual meetings of the Population Association of America, Denver, Colorado, April 30–May 2, 1992.  相似文献   
36.
There is much evidence to suggest that scleroderma in human patients is caused by a fundamental defect in the immune system. In tightskin mice, the scleroderma syndrome is associated with autoimmunity, particularly autoantibodies interacting with scleroderma target antigens.  相似文献   
37.
OBJECTIVE We studied the macrolide antibiotic FK-506, an immunosuppressive agent, in an attempt to ameliorate the lesion of autoimmune thyroid disease in human thyroid tissue xenografted into severe combined immunodeficient (SCID) mice. It was not felt appropriate to employ this agent directly in patients with autoimmune thyroid disease because adequate therapeutic modalities are available and the introduction of new, experimental agents could not be justified. Moreover, the study of the tissue before and after treatment could not have been undertaken directly in patients. DESIGN Human thyroid xenografts from four patients with Graves' disease and two normal persons were xenografted into SCID mice. Two weeks after xenograft-ing, human immunoglobulin G (IgG) was detectable in all SCID mice xenografted with Graves' thyroid tissue. Mice were divided into two groups with human IgG levels similar to each other. Mice in the first group were treated with FK-506 daily for 6 weeks; mice in the second (similar) group were given phosphate-buffered saline (PBS) only (control group). MEASUREMENTS Blood samples were taken every 2 weeks from the tail veins for human IgG, thyroid stimulating antibody, thyroperoxidase antibodies, thyroglobulin antibodies, and interferon-gamma (IFN-7). After 8 weeks treatment, animals were sacrificed; thyroid tissue was examined histologically and for thyrocyte HLA-DR expression. FK-506 was also added to thyrocytes in in-vitro tissue culture conditions. RESULTS After 4–6 weeks of FK-506 therapy, human IgG, all thyroid antibodies and IFN-7 were suppressed, while the levels remained elevated in the control group. Lymphocytic infiltration virtually disappeared in the human thyroid tissue of the FK-506-treated mice and thyrocyte HLA-DR expression markedly declined; in the control mice, lymphocytic infiltration remained heavy and HLA-DR expression remained high. On the other hand, FK-506 added directly to thyrocytes in vitro (without lymphocytes) did not reduce thyrocyte HLA-DR expression. CONCLUSIONS FK-506 appears to suppress the activation of intrathyroidal lymphocytes, but not thyrocytes. From these observations, it is concluded that this agent, by its action on intrathyroidal lymphocytes, is able to ameliorate the immunologically mediated histological and serological disturbance in human autoimmune thyroid disease, at least under these circumstances.  相似文献   
38.
Patients with stage T3N0~2M0 gastric carcinoma (n = 108) were studied for relevant prognostic factors. Peritoneal lavage cytology (PLC) was performed in all. In univariate analysis, 5-year survival rates were better with smaller serosal invasion (diameter <3.0 cm vs. ≥3.0 cm, 61% vs. 37%, P < 0.05) and fewer metastatic nodes (≤5 vs. ≥6, 57% vs. 29%, P < 0.05). In multivariate analyses, only these two factors were significant. The predictive value of PLC was not shown in both univariate and multivariate analyses. Peritoneal recurrence occured in 14 (22%) of 77 patients with negative PLC, and in 3 (18%) of 17 with positive PLC, the difference being not significant. Our results indicate that PLC is insensitive in predicting the development of peritoneal recurrence. Its role in the estimation of survival is limited, as many will die of visceral or locoregional recurrence if not of peritoneal dissemination.  相似文献   
39.
Endoscopic resection has been accepted as the standard treatment for intramucosal gastric tumors of differentiated type. However, the indication was limited to small tumors to achieve en bloc resection and prevent local recurrence in cases of conventional endoscopic mucosal resection (EMR) such as the strip biopsy and the cap technique. To avoid multi‐fragmental resection, we have developed endoscopic submucosal dissection (ESD) as a new endoscopic resection technique. ESD is a remarkable technique, because we make it possible to remove the lesions en bloc regardless of size, shape, coexisting ulcer, and location. However, it is difficult or impossible to resect recurrent tumors en bloc in conventional EMR owing to hard fibrosis, and some patients need laparotomy. Using ESD, we can dissect the submucosal layer as we directly look at the submucosa, and remove the lesion safely and reliably even in cases of hard fibrosis. The key to treatment of recurrent tumors in ESD are as follows: (i) using enough submucosal injection solution (we use a mixture of Glyceol and 1% 1900 kDa hyaluronic acid preparation); (ii) incising the mucosa without fibrosis; (iii) understanding characteristics of various cutting devices, and changing other devices in difficult situations. In these ways we can remove the majority of the recurrent tumors en bloc. Hence, we consider that ESD is a very effective treatment which achieves excellent en bloc and complete resection rates and enables patients with intramucosal gastric tumors to a recurrent‐free survival even in recurrent tumors.  相似文献   
40.
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