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31.
Establishing phenotypic features associated with morbidity in human T-cell lymphotropic virus type 1 infection 总被引:1,自引:0,他引:1
Brito-Melo GE Souza JG Barbosa-Stancioli EF Carneiro-Proietti AB Catalan-Soares B Ribas JG Thorum GW Rocha RD Martins-Filho OA;Grupo Interdisciplinar de Pesquisas em HTLV 《Clinical and diagnostic laboratory immunology》2004,11(6):1105-1110
The human T-cell lymphotropic virus type 1 (HTLV-1) is the causative agent of HTLV-1-associated myelopathy/tropical spastic paraparesis (HT). Although it is widely believed that virus infection and host immune response are involved in the pathogenic mechanisms, the role of the immune system in the development and/or maintenance of HT remains unknown. We performed an analysis of the peripheral blood leukocyte phenotype for two different subcohorts of HTLV-1-infected individuals to verify the existence of similar immunological alterations, possible laboratory markers for HT. The leukocyte population balance, the activation status of the T lymphocytes, and the cellular migratory potential of T lymphocytes, monocytes, and neutrophils were evaluated in the peripheral blood of HTLV-1-infected individuals classified as asymptomatic individuals, oligosymptomatic individuals, and individuals with HT. Data analysis demonstrated that a decreased percentage of B cells, resulting in an increased T cell/B cell ratio and an increase in the CD8+ HLA-DR+ T lymphocytes, exclusively in the HT group could be identified in both subcohorts, suggesting its possible use as a potential immunological marker for HT for use in the laboratory. Moreover, analysis of likelihood ratios showed that if an HTLV-1-infected individual demonstrated B-cell percentages lower than 7.0%, a T cell/B cell ratio higher than 11, or a percentage of CD8+ HLA-DR+ T lymphocytes higher than 70.0%, this individual would have, respectively, a 12-, 13-, or 22-times-greater chance of belonging to the HT group. Based on these data, we propose that the T cell/B cell ratios and percentages of circulating B cells and activated CD8+ T lymphocytes in HTLV-1-infected patients are important immunological indicators which could help clinicians monitor HTLV-1 infection and differentiate the HT group from the asymptomatic and oligosymptomatic groups. 相似文献
32.
Moreira-Leite FF de Souza W da Cunha-e-Silva NL 《Molecular and biochemical parasitology》1999,104(1):131-140
The paraflagellar rod (PFR) is a component of the flagellar cytoskeleton of trypanosomatid protozoa, representing a filamentous structure that runs alongside the common 9 + 2 microtubular axoneme. The high degree of ultrastructural complexity and organization of the PFR suggests that it might be formed by numerous biochemical components. However, biochemical analysis of the PFR has revealed, to date, a modest degree of complexity in what concerns both major and minor PFR proteins. In this paper the preparation of purified PFR fractions by a combination of conventional cell-fractionation procedures, non-ionic detergent treatment and limited proteolysis is described. Comparative SDS-PAGE analysis of the different purification steps indicates that the purified PFR fractions possess high amounts of the well-known major PFR proteins (77 and 83 kDa). Also, bands of 147, 139, 129 and 122 kDa are clearly enriched in such fractions and may correspond to minor PFR components. A slight enrichment in a specific fraction of a doublet of bands of 181/188 kDa suggest the participation of these proteins in the composition of the bridges between the PFR and the axoneme. 相似文献
33.
Lamerdin JE Yamada NA George JW Souza B Christian AT Jones NJ Thompson LH 《Mutagenesis》2004,19(3):237-244
The human FANCG/XRCC9 gene, which is defective in Fanconi anemia complementation group G (FA-G) cells, was first cloned by genetic complementation of the mitomycin C (MMC) sensitivity of CHO mutant UV40. The CHO NM3 mutant was subsequently assigned to the same complementation group. The parental AA8 CHO cells are hemizygous at the FancG locus, and we identified frameshift mutations that result in N-terminal truncations of the protein in both UV40 and NM3. Hypersensitivity to DNA cross-linking agents, such as MMC, typically characterizes FA cells. By introducing the native CHO FancG gene into mutant NM3, we demonstrate that hamster FancG fully corrects the 3-fold sensitivity to methyl methanesulfonate (MMS) as well as the 10-fold sensitivity to MMC, whereas resistance to ionizing radiation did not increase appreciably. In contrast, hamster cDNA transformants showed incomplete correction for both MMC and MMS sensitivity. The constitutively expressed FancG protein is present in the cytoplasmic, nuclear and chromatin fractions. FancG protein levels and subcellular localization do not change appreciably as a function of cell cycle position. Our results are consistent with roles of FancG in both the nuclear and cytoplasmic compartments to maintain genomic stability in response to various genotoxic agents. 相似文献
34.
Ferreira Larissa Bueno Lobo Cecília Viana do Carmo Ariene Silva Souza Rafaela Cristina Vieira e dos Santos Luana Caroline 《Maternal and child health journal》2022,26(7):1464-1472
Maternal and Child Health Journal - Dietary patterns can influence maternal and child health outcomes. The study aims to characterize dietary patterns during pregnancy as well as to identify their... 相似文献
35.
The association between obesity and vitamin A has been studied. Some studies point to the anti-obesity activity related to this vitamin, carotenoids with provitamin A activity, and carotenoid conversion products. This performance has been evaluated in respect of adipogenesis, metabolic activity, oxidation processes, secretory function, and oxidative stress modulation, showing a new property attributed to vitamin A in preventing and treating obesity. However, vitamin A and its precursors are highly sensitive and easily degraded when subjected to heat, the presence of light, and oxygen, in addition to losses related to the processes of digestion and absorption. In this context, encapsulation presents itself as an alternative capable of increasing vitamin A’s stability in the face of unfavorable conditions in the environment, which can reduce its functionality. Considering that vitamin A’s status shows a strong correlation with obesity and is an innovative theme, this article addresses the associations between vitamin A’s consumption and its precursors, encapsulated or not, and its physiological effects on obesity. The present narrative review points out those recent studies that demonstrate that vitamin A and its encapsulated precursors have the most preserved functionality, which guarantees better effects on obesity therapy. 相似文献
36.
37.
Camargo Carlos Henrique de Souza da Cunha Maria de Lourdes Ribeiro Caramori Jacqueline Costa Teixeira Mondelli Alessandro Lia Montelli Augusto Cezar Barretti Pasqual 《International urology and nephrology》2021,53(2):381-381
International Urology and Nephrology - In the original publication, article title was incorrectly published. 相似文献
38.
Amanda Souza Setti Daniela Paes de Almeida Ferreira Braga Livia Vingris Assumpto Iaconelli Jr. Edson Borges Jr. 《Andrologia》2021,53(11):e14211
The objective of this study was to investigate the impact of male age, semen quality and days of ejaculatory abstinence on embryo morphokinetics. A total of 1,220 zygotes obtained from 139 couples in a private in vitro fertilisation centre were analysed. The timing of specific events from the point of insemination, such as timings to pronuclei appearance and fading, to two, three, four, five, six, seven and eight cells and to blastulation were recorded. Multivariate linear regression analysis was used to evaluate the influence of paternal factors on embryo morphokinetic events. Paternal age was positively correlated with delayed cell cleavage and blastulation, and negatively associated with implantation rate, and clinical pregnancy and live–birth chances. The ejaculatory abstinence was inversely correlated with the implantation rate. Inverse relationships were observed between semen parameters (sperm count, progressive sperm motility, total motile sperm count and morphology) and the timing of specific events during embryo development. Sperm morphology was also positively associated with implantation rate and pregnancy and live–birth chances. Increased paternal age and ejaculatory abstinence, and poor semen quality correlate with delayed cell cleavage and blastulation and negatively impact intracytoplasmic sperm injection outcomes. 相似文献
39.
40.
Henrique Filho VN Walter Filho FA Souza HA Leal TA Tenório AL 《Jornal de pediatria》1994,70(5):302-304
A four years-old boy with Xanthogranulomatous pyelonephritis was surgically treated at the Pediatric Surgery Unit of the Santa Casa de Misericórdia of Maceió. Comments are made upon pathology, pre-operative diagnostic difficulties, differential diagnosis, and the rare occurrence in children. 相似文献