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Miriam Pires de Castro Oliveira Thiago Cesar Prata Ramos Adriana Maria V.N. Pinheiro Silvio Bertini Helio Kiyoshi Takahashi Anita Hilda Straus Edna Freymuller Haapalainen 《Acta tropica》2013
Trypanosoma (Schizotrypanum) dionisii is a non-pathogenic bat trypanosome closely related to Trypanosoma cruzi, the etiological agent of Chaga's disease. Both kinetoplastids present similar morphological stages and are able to infect mammalian cells in culture. In the present study we examined 3D ultrastructure aspects of the two species by serial sectioning epimastigote and trypomastigote forms, and identified common carbohydrate epitopes expressed in T. dionisii, T. cruzi and Leishmania major. A major difference in 3D morphology was that T. dionisii epimastigote forms present larger multivesicular structures, restricted to the parasite posterior region. These structures could be related to T. cruzi reservosomes and are also rich in cruzipain, the major cysteine-proteinase of T. cruzi. We analyzed the reactivity of two monoclonal antibodies: MEST-1 directed to galactofuranose residues of glycolipids purified from Paracoccidioides brasiliensis, and BST-1 directed to glycolipids purified from T. cruzi epimastigotes. Both antibodies were reactive with T. dionisii epimastigotes by indirect immunofluorescense, but we noted differences in the location and intensity of the epitopes, when compared to T. cruzi. In summary, despite similar features in cellular structure and life cycle of T. dionisii and T. cruzi, we observed a unique morphological characteristic in T. dionisii that deserves to be explored. 相似文献
83.
Fang BS Sneller MC Straus SE Frenkel L Dale JK Rick ME 《American journal of hematology》2000,64(3):214-217
The occurrence of factor VIII inhibitors in non-hemophilic patients is a rare event with a potentially lethal outcome. Despite its infrequent occurrence, the association of this inhibitor with multiple autoimmune diseases is well recognized. We report the case of a patient with the recently described autoimmune lymphoproliferative syndrome (ALPS) who developed an inhibitor to factor VIII. ALPS is a disease characterized by defective lymphocyte apoptosis due to inherited mutations in genes that regulate apoptosis, with the resulting enlargement of lymphoid organs and a variety of autoimmune manifestations. Published 2000 Wiley-Liss, Inc. 相似文献
84.
McKenzie R Reynolds JC O'Fallon A Dale J Deloria M Blackwelder W Straus SE 《The Journal of rheumatology》2000,27(9):2222-2226
OBJECTIVE: While osteoporosis and bone fractures are clearly recognized side effects of high dose glucocorticoids, the effect of low dose glucocorticoids remains controversial. We investigated the effect of 3 months of low dose hydrocortisone on bone mineral density (BMD). METHODS: Subjects, 18 to 55 years old with chronic fatigue syndrome and no medical or psychiatric illness requiring medication, were randomized in a double blind, placebo controlled trial to receive oral hydrocortisone, 13 mg/m2 body surface area every morning and 3 mg/m2 every afternoon (25 to 35 mg/day, equivalent to about 7.5 mg prednisone/day) or placebo for 12 weeks. Before and after treatment BMD of the lumbar spine was measured by dual energy x-ray absorptiometry. RESULTS: We studied 23 subjects (19 women, 4 men). For the 11 hydrocortisone recipients there was a mean decrease in BMD: mean change from baseline of the lateral spine was -2.0% (95% CI -3.5 to -0.6. p = 0.03) and mean change of the anteroposterior spine was -0.8% (95% CI -1.5 to -0.1, p = 0.06). Corresponding changes for the 12 placebo recipients were +1.0% (95% CI -1.0 to 3.0, p = 0.34) and +0.2% (95% CI -1.4 to 1.5, p = 0.76). CONCLUSION: A 12 week course of low dose glucocorticoids given to ambulatory subjects with chronic fatigue syndrome was associated with a decrease in BMD of the lumbar spine. This decrease was statistically significant in lateral spine measurements and nearly so in anteroposterior spine measurements. 相似文献
85.
目的:探讨如达溃疡散对大鼠乙酸性胃溃疡的作用及对其血清促胃液素(gastrin)含量的影响.方法:采用乙酸法复制胃溃疡模型,将大鼠随机分为对照组、如达溃疡散组、雷尼替丁组,观察如达溃疡散对大鼠胃溃疡的作用,并检测其对大鼠血清中促胃液素含量的影响.结果:与对照组相比,如达溃疡散能明显抑制溃疡的发生,抑制血清促胃液素含量.结论:如达溃疡散具有抗胃溃疡的作用,其作用机理可能是通过抑制促胃液素释放,进一步减少胃酸分泌来实现的. 相似文献
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Straus WL Eisen GM Sandler RS Murray SC Sessions JT 《The American journal of gastroenterology》2000,95(2):479-483
OBJECTIVE: The severity of Crohn's disease (CD) has been reported to be greater in blacks than in whites. This possible disparity may be due, in part, to differences between these groups in health care utilization and accessibility. To explore these issues, we conducted a multicenter survey of patients with CD. METHODS: One-hundred and forty-five blacks with CD, recruited from four teaching hospitals and five private practices, and identified by medical record review or ICD-9 code, were enrolled and matched to 407 whites with CD (by age, gender, and practice type [teaching vs. private practice setting]). Participants were interviewed regarding medical history, health status, personal health care practices during the preceding 5 yr, and beliefs regarding health care in the general population. RESULTS: Blacks and whites were similar with respect to age of CD onset, lag in time to diagnosis, and number of gastrointestinal (GI)-related hospitalizations and surgeries. Medication usage patterns were also similar in the two groups. Quality of life, measured by SF-36, was lower in all categories for blacks, compared with whites. Blacks were more likely to have had to stop work (p<0.01) and have lost more work days (p<0.01) than were whites. Whites were more likely to have health insurance and be able to identify a regular provider than were blacks. Blacks were more likely to report the following: receiving Medicaid; difficulty affording health care; delaying appointments due to financial concerns; difficulty traveling to their provider's office; and experiencing unreasonable delays at their provider's office. After adjusting for potential confounding variables, we found no differences between the groups, except for the number of days of work lost because of CD. CONCLUSIONS: These data suggest that black and white patients have similar reported disease presentations and course, and contrast with prior reports suggesting a more severe disease course among black patients. Although the disease itself appears similar, there were numerous reported differences between the races in health care utilization practices and in disease impact upon daily activities. We suggest that apparent disparities in CD according to race are actually due to social and economic factors, and not to the disease itself. 相似文献
89.
E Somekh D G Tedder A Vafai J G Assouline S E Straus C L Wilcox M J Levin 《Pediatric research》1992,32(6):699-703
A potential in vitro model of varicella-zoster virus (VZV) latency was developed. Dissociated human dorsal root ganglion cultures were infected with VZV and maintained for 1 wk in the presence of bromovinyl arabinosyl uracil, a potent inhibitor of VZV. Seven to 21 d after removing the inhibitor (> or = 14 d after infection), the cells were trypsinized, passed to monolayers of human embryonic lung fibroblasts, and observed for VZV reactivation as indicated by typical cytopathic effects and the appearance of VZV antigens. VZV reactivated from 56% of the cultures containing both neurons and satellite cells but not from cultures specifically enriched for either neurons, satellite cells, or ganglion-derived fibroblasts. The failure to isolate VZV from cell suspensions that were sonicated before cocultivation with fibroblasts indicated that infectious VZV was not present before reactivation. Moreover, immunohistochemical and immunoprecipitation studies revealed no VZV-specific antigens in any cultures before the reactivation stimulus. VZV antigens were detected after trypsinization and cocultivation. These findings suggest that cultures containing both neurons and satellite cells provide a model system for VZV persistence that possesses many properties of a latent infection. 相似文献
90.