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91.
Benjamin B. Gelman MD PhD Dwayne A. Wolf MD PhD Juan Pablo Olano MD Lannette C. Linthicum MD 《Human pathology》1996,27(12):1282-1287
The Texas Department of Criminal Justice (TDCJ) houses many subjects with acquired immunodeficiency syndrome (AIDS) who receive medical care in a comprehensive AIDS treatment center. In this case-control autopsy survey, we compared pathological outcomes of TDCJ inmates treated at the center (n = 155) with nonincarcerated patients who died during the same period (n = 155). Using multiple regression analysis and a proportional hazards model, survival time in the prisoners was equivalent to that in the controls. With few exceptions, the prevalences of opportunistic viral, fungal, protozoal, and bacterial infections contributing to mortality were equivalent between groups. Mycobacterium tuberculosis was isolated more frequently in the inmates, and M avium intracellulare was isolated less frequently (P < .0001). The inmates had a higher prevalence of bacterial infection of the central nervous system (CNS) (9.1% v 1.4%; P < .006); half of all CNS bacterial infections were caused by M tuberculosis. Inmates had significantly lower prevalences of vacuolar myelopathy (P < .006) and severe wasting disease (P < .0009). We conclude that survival of prison inmates with AIDS treated in a comprehensive AIDS treatment center was equivalent to that of nonincarcerated subjects with AIDS. Prevalences of certain complications of AIDS differed in the inmates, showing that the prison environment influenced some of the underlying causes of AIDS morbidity and mortality. 相似文献
92.
Alberto Utrero-Rico Javier Ruiz-Hornillos Cecilia González-Cuadrado Claudia Geraldine Rita Berta Almoguera Pablo Minguez Antonio Herrero-González Mario Fernández-Ruiz Octavio Carretero Juan Carlos Taracido-Fernández Rosario López-Rodriguez Marta Corton José María Aguado Luisa María Villar Carmen Ayuso-García Estela Paz-Artal Rocio Laguna-Goya 《The Journal of allergy and clinical immunology》2021,147(5):1652-1661.e1
93.
HGT1 encodes a high-affinity glutathione transporter in the yeast Saccharomyces cerevisiae that is induced under sulphur limitation. The present work demonstrates that repression by organic sulphur sources is under the control of the classic sulphur regulatory network, as seen by the absence of expression in a met4 background. Cysteine appeared to be the principal regulatory molecule, since elevated levels were seen in str4 strains (deficient in cysteine biosynthesis) that could be repressed by elevated levels of cysteine, but not by methionine or glutathione. Investigations into cis-regulatory elements revealed that the previously described motif, a 9-bp cis element, CCGCCACAC, located at the –356 to –364 region of the promoter could in fact be refined to a 7-bp CGCCACA motif that is also repeated at –333 to –340. The second copy of this motif was essential for activity, since mutations in the core region of the second copy completely abolished activity and regulation by sulphur sources. Activity, but not regulation, could be restored by reintroducing an additional copy upstream of the first copy. A third region, GCCGTCTGCAAGGCA, conserved in the HGT1 promoters of the different Saccharomyces spp, was observed at –300 to –285 but, while mutations in this region did not lead to any loss in repression, the basal and induced levels were significantly increased. In contrast to a previous report, no evidence was found for regulation by the VDE endonuclease. The strong repression at the transport level by glutathione seen in strains overexpressing HGT1 was due to a glutathione-dependent toxicity in these cells. 相似文献
94.
Gilissen LJ Bolhaar ST Matos CI Rouwendal GJ Boone MJ Krens FA Zuidmeer L Van Leeuwen A Akkerdaas J Hoffmann-Sommergruber K Knulst AC Bosch D Van de Weg WE Van Ree R 《The Journal of allergy and clinical immunology》2005,115(2):364-369
BACKGROUND: Apple allergy is dominated by IgE antibodies against Mal d 1 in areas where birch pollen is endemic. Apples with significantly decreased levels of Mal d 1 would allow most patients in these areas to eat apples without allergic reactions. OBJECTIVE: The aim of this study was to inhibit the expression of Mal d 1 in apple plants by RNA interference. METHODS: In vitro -grown apple plantlets were transformed with a construct coding for an intron-spliced hairpin RNA containing a Mal d 1-specific inverted repeat sequence separated by a Mal d 1-specific intron sequence. The presence of the construct in transformants was checked by PCR. Expression of Mal d 1 in leaves was monitored by prick-to-prick skin testing in 3 patients allergic to apples and by immunoblotting with a Mal d 1-reactive mAb and with IgE antibodies against Mal d 1. RESULTS: After transformation, plantlets were selected on the basis of having a normal phenotype and growth rate. With PCR, in 6 of 9 selected plantlets, the presence of the gene-silencing construct was demonstrated. By skin prick test it was shown that a wild-type plantlet had significantly ( P < .05) higher allergenicity than 5 of the transformants. Reduction of expression of Mal d 1 was confirmed by immunoblotting. In wild-type and unsuccessful transformants, a strong band was detected with Mal d 1-reactive mAb 5H8 at the expected apparent M r of 17 kDa. This band was virtually absent in the transformants that carried the gene-silencing construct. With human IgE antibodies, the same observations were made. CONCLUSIONS: Mal d 1 expression was successfully reduced by RNA interference. This translated into significantly reduced in vivo allergenicity. These observations support the feasibility of the production by gene silencing of apples hypoallergenic for Mal d 1. 相似文献
95.
Safety of sublingual-swallow immunotherapy in children and adults 总被引:13,自引:0,他引:13
André C Vatrinet C Galvain S Carat F Sicard H 《International archives of allergy and immunology》2000,121(3):229-234
96.
Enteropathogenic Escherichia coli strains carrying genes encoding the PER-2 and TEM-116 extended-spectrum beta-lactamases isolated from children with diarrhea in Uruguay 总被引:2,自引:0,他引:2 下载免费PDF全文
Vignoli R Varela G Mota MI Cordeiro NF Power P Ingold E Gadea P Sirok A Schelotto F Ayala JA Gutkind G 《Journal of clinical microbiology》2005,43(6):2940-2943
We studied 13 extended-spectrum beta-lactamase (ESBL)-producing enteropathogenic Escherichia coli isolates from children suffering acute diarrhea in Uruguay. ESBL characterization in crude extracts showed a single band at pI 5.4. PCR amplification and sequencing data allowed identification of blaPER-2 and blaTEM-116. Retrospective analysis suggests that these strains were disseminated in the community, even if unnoticed, prior to their access to the hospital environment more than a decade ago. 相似文献
97.
The thermal responses of neonates during a cool acclimation period were studied with regard to sleep stages. Sleep stages, body temperatures and metabolic rate (VO2) were studied for seven neonates nursed in incubators and exposed to a cool temperature (thermoneutrality minus 2 degrees C) for 75 h. Each recording session lasted 3 h in the morning: firstly under thermoneutral baseline conditions, then during the first and last 3-h periods of the cool acclimation and finally during the last 3 h of a 24-h recovery period. Sleep structure was modified during the initial hours of cool exposure: the percentage of active sleep increased (AS: +13%, P = 0.028) at the expense of quiet sleep (QS: -11%, P = 0.043). This alteration in sleep structure persisted at the end of the acclimation period. Metabolic heat production only increased in the later period of cool acclimation. Throughout the cool exposure, VO2 increased more (P = 0.040) in QS (+33%) than in AS (+20%) so that by the end of the cool period, VO2 levels were similar in both sleep stages. During cool acclimation, the maintenance of homeothermy is related not only to a change in sleep organization but also to modifications in the thermoregulatory processes in both sleep stages. Considering the importance of AS/QS patterns in the neurobehavioral development of neonates, the present results could have clinical implications for the thermal management of neonates. 相似文献
98.
Rheumatic heart disease: proinflammatory cytokines play a role in the progression and maintenance of valvular lesions 总被引:3,自引:0,他引:3 下载免费PDF全文
Guilherme L Cury P Demarchi LM Coelho V Abel L Lopez AP Oshiro SE Aliotti S Cunha-Neto E Pomerantzeff PM Tanaka AC Kalil J 《The American journal of pathology》2004,165(5):1583-1591
Heart lesions of rheumatic heart disease (RHD) patients contain T-cell clones that recognize heart proteins and streptococcal M peptides. To functionally characterize heart-infiltrating T lymphocytes, we evaluated their cytokine profile, both directly in situ and in T-cell lines derived from the heart (HIL). Interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, interleukin (IL)-4, and IL-10 expressions were characterized in 20 heart tissue infiltrates from 14 RHD patients by immunohistochemistry. IFN-gamma-, TNF-alpha-, and IL-10-positive cells were consistently predominant, whereas IL-4 was scarce in the valves. In agreement with these data, the in vitro experiments, in which 13 HILs derived from heart samples of eight patients were stimulated with M5 protein and the immunodominant M5 (81-96) peptide, IL-4 was detected in HIL derived from the atrium (three of six) but not from the valve (zero of seven). IFN-gamma and IL-10 production were detected in culture supernatants in 11 of 13 and 6 of 12 HILs, respectively. The predominant IFN-gamma and TNF-alpha expression in the heart suggests that Th1-type cytokines could mediate RHD. Unlike in reversible myocardium inflammation, the significantly lower IL-4 expression in the valvular tissue (P = 0.02) may contribute to the progression of the RHD leading to permanent valvular damage (relative risk, 4.3; odds ratio, 15.8). The lack of IL-4 in vitro production by valve-derived HIL also emphasizes the more severe tissue destruction in valves observed in RHD. 相似文献
99.
Navin Wadehra Sherif Farag Brian Bolwell Patrick Elder Sam Penza Matt Kalaycio Belinda Avalos Brad Pohlman Guido Marcucci Ronald Sobecks Thomas Lin Steven Andrèsen Edward Copelan 《Biology of blood and marrow transplantation》2006,12(12):1343-1349
Busulfan (Bu)-based preparative regimens have not been extensively investigated in Hodgkin disease (HD). The purposes of this study were to investigate the toxicity and efficacy of a novel preparative regimen of Bu 14 mg/kg, etoposide 50-60 mg/kg, and cyclophosphamide 120 mg/kg in patients with primary refractory and relapsed HD. One hundred twenty-seven patients with a median age of 33 years (range, 14-67 years) underwent transplantation. The regimen was well tolerated, with 5.5% treatment-related mortality at 100 days after transplantation. With a median follow up of 6.7 years, the 5-year progression-free survival was 48 +/- 5%, and the 5-year overall survival was 51 +/- 5%. A Cox proportional hazards model identified refractory disease at time of transplantation as the only significant factor affecting relapse and overall survival, whereas disease bulk >10 cm affected overall survival. Five patients died between 5.3 and 9.3 years of late complications, including secondary myelodysplasia or acute myeloid leukemia, secondary solid malignancies, and pulmonary toxicity. This novel Bu regimen is comparable to other radiation-free preparative regimens in its effectiveness in the control of HD and with a low-risk of early treatment-related mortality. 相似文献
100.
David Tarrag Julio Casal Jesús Ruiz-Contreras J. Toms Ramos Pablo Rojo Harm Snippe Wouter T. M. Jansen 《Clinical and Vaccine Immunology : CVI》2005,12(1):165-170
We investigated antibody responses against pneumococci of serotypes 6B, 14, and 23F in 56 children and adolescents with perinatal human immunodeficiency virus (HIV) infection who were vaccinated with 7-valent pneumococcal conjugate vaccine. Overall immune responses differed greatly between serotypes. Correlation coefficients between immunoglobulin G (IgG) measured by enzyme-linked immunosorbent assay (ELISA) and functional antibodies measured by a flow cytometry opsonophagocytosis assay (OPA) varied with serotype and time points studied. After 3 months of administering a second PCV7 dose we got the highest correlation (with significant r values of 0.754, 0.414, and 0.593 for serotypes 6B, 14, and 23F, respectively) but no significant increase in IgG concentration and OPA titers compared to the first dose. We defined a responder to a serotype included in the vaccine with two criteria: frequency of at least twofold OPA and ELISA increases for each serotype and frequency of conversion from negative to positive OPA levels. Responders varied from 43.9% to 46.3%, 28.5% to 50.0%, and 38.0% to 50.0% for serotypes 6B, 14, and 23F, respectively, depending on the response criterion. The present research highlights the importance of demonstrating vaccine immunogenicity with suitable immunological endpoints in immunocompromised patients and also the need to define how much antibody is required for protection from different serotypes, since immunogenicity differed significantly between serotypes. 相似文献