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991.
992.
Paloma da Cunha de Medeiros Ricardo Rodrigues Samelo Ana Priscila Gomes Silva Marcella da Silva Araujo Santiago Fabio Andrei Duarte Ítalo Braga de Castro Juliana Elaine Perobelli 《Environmental toxicology》2019,34(1):83-91
For the first time, juvenile toxicity of inorganic arsenic (As) was investigated in male rats, focusing on reproductive effects. As is a metalloid naturally occurring in the environment, being the inorganic forms the most toxics. Contaminated drinking water and agricultural products are the main prospectors of intoxication for general population. In the present study, Wistar male rats (21 days old) were distributed into three groups (n = 10/group): control (received vehicle‐filtered drinking water), As1 (received AsNaO2 at 0.01 mg L?1) and As2 (received AsNaO2 at 10 mg L?1). The animals were euthanized on PND 53. Testicular damages increased in As1 and As2 compared to control (ie, presence of vacuolization, acidophilic cells, and epithelium degeneration). Testicular interstitium of As1 and As2 presented fluid's increase and intense inflammatory infiltration. In the epididymis there was reduction of sperm amount in the lumen, besides epithelium areas presenting cribriform aspect in As1 and As2, exfoliation of cells in the light (in As1) and vacuoles (in As2). In epididymis interstitium, inflammatory infiltrates were observed in initial segment of As1 and As2. AsNaO2 changed immunolabeling pattern for androgen receptor in epididymis of As2, although serum testosterone levels was statistically comparable to control. Mass spectrometry revealed higher As concentrations in testis and epididymis of As2 compared to As1 and Control. These results indicate compromise of spermatogenesis and epididymal histophysiology in AsNaO2‐treated animals, possibly impairing sperm quality and fertility in long‐term, even at low levels of exposure. Investigations about the reversibility of reproductive damages are necessary to better understand the mechanisms of As reproductive toxicity. 相似文献
993.
M.H. Houman N. Bel Feki 《La Revue de médecine interne / fondée ... par la Société nationale francaise de médecine interne》2014
Although the precise pathogenesis and etiology of Behçet's disease (BD) still remains unknown, current evidence suggests that inflammatory reaction in BD arises from disruption of homeostasis in genetically susceptible individuals, resulting in altered innate and adaptive immunity responses, pathogenic T cell activation in the peripheral blood, and in inflammatory sites. Association with HLA-B51 is known as the strongest genetic susceptibility factor for BD. Recent GWAS (genome-wide association studies) have confirmed this relationship, and reported new susceptibility genes (IL-10, IL-23R, IL-12RB2) for the disease. A triggering infectious agent could operate through molecular mimicry, and the disease could subsequently be perpetuated by an abnormal immune response to an auto-antigen in the absence of ongoing infection. Several potential bacteria have been investigated but the most commonly implicated microorganism is Streptococcus sanguis. Recent data have showed that the T cell homeostasis perturbation consisted mainly of Th1 and Th17 expansions, while regulatory T cell response was suppressed. Cytokine such as IL-17, IL-23 and IL-21 play a significant role in the pathogenesis of BD. Inflammatory cells within BD inflammatory lesions include mostly neutrophils, CD4+ T cells, and cytotoxic cells. Lastly, endothelium dysfunction has been clearly established. This improved understanding of the pathophysiology of BD will certainly lead to the development of new therapeutic agents, potentially more effective than current therapy. In this review, we have studied the etiopathogenesis of BD in the light of recent advances. 相似文献
994.
Emilie Mamessier Joo Y. Song Franziska C. Eberle Svetlana Pack Charlotte Drevet Bruno Chetaille Ziedulla Abdullaev José Adela?de Daniel Birnbaum Max Chaffanet Stefania Pittaluga Sandrine Roulland Andreas Chott Elaine S. Jaffe Bertrand Nadel 《Haematologica》2014,99(3):481-488
The pathogenesis of follicular lymphoma is a multi-hit process progressing over many years through the accumulation of numerous genetic alterations. Besides the hallmark t(14;18), it is still unclear which other oncogenic hits contribute to the early steps of transformation and in which precursor stages these occur. To address this issue, we performed high-resolution comparative genomic hybridization microarrays on laser-capture micro-dissected cases of follicular lymphoma in situ (n=4), partial involvement by follicular lymphoma (n=4), and duodenal follicular lymphoma (n=4), assumed to represent, potentially, the earliest stages in the evolution of follicular lymphoma. Cases of reactive follicular hyperplasia (n=2), uninvolved areas from follicular lymphoma in situ lymph nodes, follicular lymphoma grade 1–2 (n=5) and follicular lymphoma grade 3A (n=5) were used as controls. Surprisingly, alterations involving several relevant (onco)genes were found in all entities, but at significantly lower proportions than in overt follicular lymphoma. While the number of alterations clearly assigns all these entities as precursors, the pattern of partial involvement by follicular lymphoma alterations was quantitatively and qualitatively closer to that of follicular lymphoma, indicating significant selective pressure in line with its faster rate of progression. Among the most notable alterations, we observed and validated deletions of 1p36 and gains of the 7p and 12q chromosomes and related oncogenes, which include some of the most recurrent oncogenic alterations in overt follicular lymphoma (TNFRSF14, EZH2, MLL2). By further delineating distinctive and hierarchical molecular and genetic features of early follicular lymphoma entities, our analysis underlines the importance of applying appropriate criteria for the differential diagnosis. It also provides a first set of candidates likely to be involved in the cascade of hits that pave the path of the various progression phases to follicular lymphoma development. 相似文献
995.
996.
Sara Raponi Caterina Ilari Irene Della Starza Luca V. Cappelli Luciana Cafforio Alfonso Piciocchi Valentina Arena Paola Mariglia Francesca R. Mauro Massimo Gentile Giovanna Cutrona Riccardo Moia Chiara Favini Fortunato Morabito Davide Rossi Gianluca Gaidano Anna Guarini Ilaria Del Giudice Robin Foà 《British journal of haematology》2020,189(5):853-859
In chronic lymphocytic leukaemia (CLL), caution is warranted regarding the clinical implications of immunoglobulin variable heavy chain region (IGHV) rearrangements with a ‘borderline’ (BL) percentage of mutations (i.e. 97–97·9% IGHV identity). We analysed the IGHV mutational status in 759 untreated CLL patients (cohort 1). BL-CLL (n = 36, 5%) showed a time to first treatment (TFT) similar to that of M-CLL (n = 338) and significantly longer than that of UM-CLL (n = 385), despite the enrichment in subset #2 cases. In fact, CLLs belonging to subset #2 (n = 15/759, 2%) were significantly more frequent among BL-CLLs (n = 5/36, 14%), with a brief TFT. TFT of BL-CLL remained comparable to that of M-CLL also considering the 327 CLL patients evaluated at diagnosis. These findings were then validated in an independent cohort 2 of 759 newly diagnosed CLL patients (BL-CLL: n = 11, 1·4%) and in all newly diagnosed patients from cohorts 1 and 2 (n = 1 086, 84% stage A; BL-CLL: n = 47, 4·3%). BL-CLL at diagnosis showed a biological profile comparable to that of M-CLL with a low frequency of unfavourable prognostic markers, except for a significant enrichment in subset #2. Our data suggest that the prognosis of BL-CLL is good and similar to that of M-CLL, with the exception of subset #2 cases. 相似文献
997.
Edson Marcio Negro Maria Cristina Del Negro Barroso Freitas Patricia Beatriz Christino Marinho Thiago Falco Hora Vinicius Viana Abreu Montanaro Bernardo Jose Alves Ferreira Martins Sergio Henrique Rodolpho Ramalho 《Arquivos brasileiros de cardiologia》2020,115(6):1144
BackgroundIschemic Stroke (IS) and Coronary Artery Disease (CAD) frequently coexist and share atherosclerotic disease risk factors. According to the American Heart Association, IS subtypes may be considered CAD risk equivalents, but the evidence for non-atherosclerotic IS is uncertain. Additionally, the Coronary Calcium Score (CCS) is an accurate marker to address CAD risk; however, CCS distribution between IS subtypes is not well characterized.ObjectivesTo compare the CCS between atherosclerotic and non-atherosclerotic IS groups; and to determine which covariates were associated with high CCS in IS.MethodsThis cross-sectional design included all patients with IS, 45 to 70 years of age at the time of the stroke, consecutively admitted to a rehabilitation hospital between August 2014 and December 2016, without prevalent CAD. All patients underwent CT scanning for CCS measurement. CCS≥100 was considered a high risk for CAD, with a significance level of p<0.05.ResultsFrom the 244 studied patients (mean age 58.4±6.8 years; 49% female), 164 (67%) had non-atherosclerotic etiology. The proportions of CCS≥100 were similar between the atherosclerotic and the non-atherosclerotic groups (33% [n=26] x 29% [n=47]; p= 0.54). Among all IS patients, only age ≥60 years was independently associated with CCS≥100 (OR 3.5; 95%CI 1.7-7.1), accounting for hypertension, dyslipidemia, diabetes, sedentarism, and family history of CAD.ConclusionAtherosclerotic IS did not present a greater risk of CAD when compared to non-atherosclerotic IS according to CCS. Only age ≥60 years, but not etiology, was independently associated with CCS≥100. 相似文献
998.
999.
1000.
Barone Roberto Clauser Carlo Testori Tiziano Del Fabbro Massimo 《Clinical oral investigations》2019,23(8):3257-3265
Clinical Oral Investigations - The aim of this study was to assess the combined role of current radiographic risk indicators and patient age in predicting lower lip sensitivity disturbances after... 相似文献