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31.
32.
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
33.
dos Santos CN Rocha CF Cordeiro M Fragoso SP Rey F Deubel V Desprès P 《Virus research》2002,90(1-2):197-205
We have investigated the genetic diversity of dengue type-1 (DEN-1) virus in Brazil. The full nucleotide sequences of three DEN-1 virus isolated from DEN fever (DF) and DEN hemorrhagic fever patients in northeastern Brazil in 1997 (BR/97) and one from a DF patient in the south of Brazil in 2001 (BR/01) were compared to that of the reference strain BR/90 obtained in the city of Rio de Janeiro in 1990. Sequence analysis showed that the structural proteins were remarkably conserved between all isolates. A total of 27 amino acid changes occurred throughout the non-structural proteins. Among them, nine amino acid substitutions were specific of BR/97 and BR/01 isolates, indicating that in situ evolution of these strains had occurred. Within the BR/97 and BR/01 samples, some amino acid substitutions have been previously identified in DEN-1 virus strains sequenced so far, suggesting that recombination events might have occurred. 相似文献
34.
35.
Development and evaluation of a rapid dipstick assay for serodiagnosis of acute human brucellosis 下载免费PDF全文
Smits HL Basahi MA Díaz R Marrodan T Douglas JT Rocha A Veerman J Zheludkov MM Witte OW de Jong J Gussenhoven GC Goris MG van Der Hoorn MA 《Journal of clinical microbiology》1999,37(12):4179-4182
A dipstick assay for the detection of brucella-specific immunoglobulin M antibodies was evaluated with 707 sera from 247 laboratory-confirmed brucellosis patients and 342 control sera from brucellosis-free individuals. These sera were collected from six different countries. The assay was found to be highly sensitive and specific. In addition, the test is easy to use and does not require specialized training or equipment, and the components are stable without a requirement for refrigeration. All of these factors make the test ideal for developing countries and rural settings. 相似文献
36.
Rocha V Wagner JE Sobocinski KA Klein JP Zhang MJ Horowitz MM Gluckman E 《The New England journal of medicine》2000,342(25):1846-1854
BACKGROUND: Umbilical-cord blood as an alternative to bone marrow for hematopoietic stem-cell transplantation may lower the risk of graft-versus-host disease (GVHD). METHODS: We studied the records of 113 recipients of cord blood from HLA-identical siblings from the period from 1990 through 1997 and compared them with the records of 2052 recipients of bone marrow from HLA-identical siblings during the same period. The study population consisted of children 15 years of age or younger. We compared the rates of GVHD, hematopoietic recovery, and survival using Cox proportional-hazards regression to adjust for potentially confounding factors. RESULTS: Recipients of cord blood were younger than recipients of bone marrow (median age, 5 years vs. 8 years; P<0.001), weighed less (median weight, 17 kg vs. 26 kg; P<0.001), and were less likely to have received methotrexate for prophylaxis against GVHD (28 percent vs. 65 percent, P<0.001). Multivariate analysis demonstrated a lower risk of acute GVHD (relative risk, 0.41; P=0.001) and chronic GVHD (relative risk, 0.35; P=0.02) among recipients of cord-blood transplants. As compared with recovery after bone marrow transplantation, the likelihood of recovery of the neutrophil count and the platelet count was significantly lower in the first month after cord-blood transplantation (relative risk, 0.40 [P<0.001], and relative risk, 0.20 [P<0.001]), respectively. Mortality was similar in the two groups (relative risk of death in the recipients of cord blood, 1.15; P=0.43). CONCLUSIONS: Recipients of cord-blood transplants from HLA-identical siblings have a lower incidence of acute and chronic GVHD than recipients of bone marrow transplants from HLA-identical siblings. 相似文献
37.
Maria Peres Manuela F. Almeida lia J. Pinto Carla Carmona Sara Rocha Arlindo Guimas Rosa Ribeiro Esmeralda Martins Anabela Bandeira Anita MacDonald Júlio C. Rocha 《Nutrients》2021,13(3)
We aimed to report the implementation of a phenylketonuria (PKU) transition program and study the effects of follow-up with an adult team on metabolic control, adherence, and loss of follow-up. Fifty-five PKU patients were analysed in the study periods (SP): 2 years before (SP1) and after the beginning of adult care (SP2). Retrospective data on metabolic control and number of clinic appointments were collected for each SP, and protein intakes were analysed. In SP2, three patients (6%) were lost to follow-up. There was a small but statistically significant increase in median number of annual blood spots from SP1 to SP2: 11 (7–15) vs. 14 (7–20); p = 0.002. Mean ± SD of median blood Phe remained stable (525 ± 248 µmol/L vs. 552 ± 225 µmol/L; p = 0.100); median % of blood Phe < 480 µmol/L decreased (51 (4–96)% vs. 37 (5–85)%; p = 0.041) and median number of clinic appointments increased from SP1 to SP2: (5 (4–6) vs. 11 (8–13); p < 0.001). No significant differences were found regarding any parameter of protein intake. Our results suggest that the implementation of an adult service was successful as impact on metabolic control was limited and attendance remained high. Continuous dietetic care likely contributed to these results by keeping patients in follow-up and committed to treatment. 相似文献
38.
Anne Daly Wolfgang Hgler Nicola Crabtree Nick Shaw Sharon Evans Alex Pinto Richard Jackson Catherine Ashmore Júlio C. Rocha Boyd J. Strauss Gisela Wilcox William D. Fraser Jonathan C. Y. Tang Anita MacDonald 《Nutrients》2021,13(6)
In patients with phenylketonuria (PKU), treated by diet therapy only, evidence suggests that areal bone mineral density (BMDa) is within the normal clinical reference range but is below the population norm. Aims: To study longitudinal bone density, mass, and geometry over 36 months in children with PKU taking either amino acid (L-AA) or casein glycomacropeptide substitutes (CGMP-AA) as their main protein source. Methodology: A total of 48 subjects completed the study, 19 subjects in the L-AA group (median age 11.1, range 5–16 years) and 29 subjects in the CGMP-AA group (median age 8.3, range 5–16 years). The CGMP-AA was further divided into two groups, CGMP100 (median age 9.2, range 5–16 years) (n = 13), children taking CGMP-AA only and CGMP50 (median age 7.3, range 5–15 years) (n = 16), children taking a combination of CGMP-AA and L-AA. Dual X-ray absorptiometry (DXA) was measured at enrolment and 36 months, peripheral quantitative computer tomography (pQCT) at 36 months only, and serum blood and urine bone turnover markers (BTM) and blood bone biochemistry at enrolment, 6, 12, and 36 months. Results: No statistically significant differences were found between the three groups for DXA outcome parameters, i.e., BMDa (L2–L4 BMDa g/cm2), bone mineral apparent density (L2–L4 BMAD g/cm3) and total body less head BMDa (TBLH g/cm2). All blood biochemistry markers were within the reference ranges, and BTM showed active bone turnover with a trend for BTM to decrease with increasing age. Conclusions: Bone density was clinically normal, although the median z scores were below the population mean. BTM showed active bone turnover and blood biochemistry was within the reference ranges. There appeared to be no advantage to bone density, mass, or geometry from taking a macropeptide-based protein substitute as compared with L-AAs. 相似文献
39.
双—对二甲氨基苯甲醛缩二胺类希夫碱合成、表征及抗菌活性 总被引:9,自引:1,他引:8
目的:合成双-对二甲氨基苯甲醛缩二胺类希夫碱,并对其抗菌活性进行研究。方法:以对二甲氨基苯甲醛和二胺类为原料,经缩合反应,制得4种相应希夫碱。结果:结构经元素分析、红外光谱、核磁共振谱确定,4种化合物均未见文献报道,抗菌活性测试表明,它们具有一定抗菌活性。结论:乙酸是催化剂,对缩合反应有利,希夫碱化合物具有一定抗菌活性。 相似文献
40.
Amadio Eliane Martins Marcos Rodrigo Labat Serra Andrey Jorge dos Santos Solange Almeida Caires Jheniphe Rocha Fernandes Guilherme Henrique Cardosos Leal-Junior Ernesto Cesar Ferrari João Carlos Correa de Tarso Camillo de Carvalho Paulo 《Lasers in medical science》2021,36(7):1427-1435
Lasers in Medical Science - Photobiomodulation therapy (PBMT) has been indicated for enforcement on healing skin wounds. This study evaluated the effects of PBMT on the healing of skin wounds... 相似文献