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101.
Lajoie J Zijenah LS Faucher MC Ward BJ Roger M;ZVITAMBO Study Group 《Human immunology》2003,64(8):823-829
Because of the essential role of transporter associated with antigen processing (TAP1 or TAP2) molecule in antigen processing, the implication of its polymorphism as a factor involved in human diseases and the possible genetic variation at this locus among ethnically diverse populations, we underwent a study to analyze the full extent of TAP1 polymorphism in an indigenous Zimbabwean population (Shona ethnic group). Using single-stranded conformation polymorphism and DNA direct sequencing procedures, we detected the presence of 11 nucleotide sequence variations in the entire coding region of TAP1. Of these variants, eight are nonconservative substitutions with respect to amino acid composition and are located in a critical part of the protein that could modulate its function. Five new polymorphic sites were identified in exon 1 (codons 7 Pro --> Ser, 17 Gly --> Arg, 141 Val --> Val), exon 6 (codon 419 Gly --> Cys), and exon 7 (codon 487 Arg --> Arg). Significant differences were seen in the distribution of TAP1*0201 and TAP1*0401 alleles, and codon 333 (Ile --> Val) polymorphism among African and non-African populations. Thus, TAP1 polymorphism has evolved differently among populations presumably because of the evolutionary pressures generated by prevalent pathogens in these geographically distinct regions. 相似文献
102.
Recruitment and baseline epidemiologic profile of participants in the first phase 3 HIV vaccine efficacy trial 总被引:2,自引:0,他引:2
Harro CD Judson FN Gorse GJ Mayer KH Kostman JR Brown SJ Koblin B Marmor M Bartholow BN Popovic V;VAX Study Group 《Journal of acquired immune deficiency syndromes (1999)》2004,37(3):1385-1392
OBJECTIVE: To describe recruitment and baseline epidemiologic characteristics of volunteers in the first phase 3 placebo-controlled trial of a recombinant gp120 HIV vaccine (AIDSVAX B/B). METHODS: Volunteers were gay/bisexual men or women at risk for sexually transmitted HIV infection. Recruitment strategies, demographics, and risk factors were assessed. HIV status was determined by standard HIV-1 antibody assays. Seronegative/viremic HIV infection at enrollment was determined using the HIV-1 nucleic acid test. RESULTS: From June 1998 through October 1999, 5417 of 7185 volunteers screened were enrolled at 61 sites in the United States, Canada, and The Netherlands. Successful recruitment methods included distribution of study information at gay venues, advertising and media coverage, and referrals from volunteers. Most volunteers were altruistically motivated, men (98%), young (median, 36 years), white (83%), well educated (61% college education or more), and at high risk for HIV during the 6 months before enrollment. At baseline, 14 were HIV infected (12 were seronegative but viremic; 2 were seropositive and viremic). CONCLUSION: Men and women at high risk for sexually transmitted HIV infection were successfully recruited for the first phase 3 HIV vaccine efficacy trial. Knowledge of recruitment and baseline epidemiologic characteristics of participants in this trial will provide valuable guidance for designing and conducting future trials. 相似文献
103.
Yamanaka H Teruya K Tanaka M Kikuchi Y Takahashi T Kimura S Oka S;HIV/Influenza Vaccine Study Team 《Journal of acquired immune deficiency syndromes (1999)》2005,39(2):167-173
Influenza vaccine is recommended for HIV-1-infected patients. The present prospective study was conducted to evaluate the clinical efficacy and immunologic responses to the vaccine. From November 1 to December 27, 2002, 262 HIV-1-infected patients received a trivalent influenza subunit vaccine, whereas 66 did not. Influenza illness occurred in 16 vaccinated and 14 nonvaccinated patients (incidence = 6.1% [95% confidence interval (CI): 4%-10%] in vaccinated vs. 21.2% [CI: 13%-35%] in nonvaccinated persons, P < 0.001; relative risk = 0.29 [CI: 0.14-0.55]). Influenza vaccine provided clinically effective protection against influenza illness in HIV-1-infected patients. In baseline antibody-negative patients, anti-H1 and anti-H3 antibody responses to the vaccination were significant in those patients with a CD4 count >200 cells/muL compared with those with a CD4 count <200 cells/muL (P < 0.05). In contrast, in baseline antibody-positive patients, good antibody responses were observed irrespective of CD4 counts, like the healthy controls. Based on these results, annual vaccination is recommended. Specific CD4 responses correlated with HIV-1 viral load (VL), especially in patients treated with highly active antiretroviral therapy (HAART) compared with those without HAART (P < 0.01), although the clinical efficacy did not correlate with HIV-1 VL. HAART may enhance the immunologic efficacy of influenza vaccine. 相似文献
104.
Dr. Gennaro D'amico MD Alberto Morabito MS Luigi Pagliaro MD Ettore Marubini MD The Liver Study Group of “V. Cervello” Hospital 《Digestive diseases and sciences》1986,31(5):468-475
Six-year survival of cirrhosis was assessed in a series of 1155 consecutive patients (751 men, 404 women). Among the men, 33% were alcoholics and 18% were HBsAg positive; corresponding figures for the women were 15% and 6%, respectively. Features of decompensation at first presentation were observed in 63% of the patients. Six-year survival was 54% in compensated and 21% in decompensated patients. No significant differences in survival were found between alcoholics and nonalcoholics. Leading causes of death were liver failure (49%), hepatocellular carcinoma (22%), and bleeding (13%). The prognostic role of 21 variables was evaluated separately in compensated and decompensated patients by the Cox's regression model. The following variables were found to be significant predictors of death risk in compensated patients: male sex, HBsAg positivity, age, prothrombin time prolongation, and esophageal varices. In decompensated disease the significant indicators of death risk were: hepatocellular carcinoma, encephalopathy, hemorrhage, SGOT, esophageal varices, gamma globulins, prothrombin time prolongation, continued abuse of alcohol, HBsAg positivity, gamma glutamyl transpeptidase, and cholinesterase. A simple prognostic index based upon the relative risk coefficient of the significant variables is suggested.Members of the Liver Study Group are: Maria Caltagirone, Gabriella Filippazzo, Giovanni Gatto, Gandolfo Giannuoli, Silvio Margin, Guiseppe Malizia, Lorenzo Maniaci, Maria Pia Marcenó, Alberto Maringhini, Rocco Micciolo, Salvatore Orsini, Fabio Pace, Ugo Palazzo, Linda Pasta, Giuseppina Russo, Rosa Giovanna Simonetti, Mario Spinello, Mario Traina, Mario Valenza, Maria Vinci, Giovanni Vizzini. 相似文献
105.
C. Gallo G. B. Gaeta B. Galanti G. Giusti Cooperative Study Group of the Italian Society for the Study of Infectious Diseases 《European journal of epidemiology》1986,2(2):95-98
The role of surgery as an additional risk in transmitting post-transfusion hepatitis was investigated in a retrospective study on acute hepatitis occurring in 77 transfused patients, 293 transfused and operated patients and 243 hepatitis cases with history of surgery without transfusion.Hepatitis A patients admitted to the same centres in the same period were utilized as controls. In transfused patients the percentage of NANB hepatitis was higher than that of type B (61.0% vs. 36.4%), while in the operated not transfused group the percentage of type B was twice that of type NANB (63.4% vs. 32.5%).In transfused and operated cases intermediate values were observed. The age-adjusted measures of association between exposures and the different hepatitis types showed a lack of effect of transfusion and a dominant role of surgery in transmitting type B hepatitis. In contrast, NANB post-transfusional cases were actually a mixture of post-transfusional and post-surgical cases, since both these exposures were found to be significantly associated with the disease.Our results suggest that studies on the incidence and the etiology of post-transfusion hepatitis should take into account the risk of surgical exposure which might have occurred.Corresponding author. 相似文献
106.
目的 编制适用于我国12~35月龄幼儿的睡眠状况评估量表,评价其信度、效度和可行性,为评估中国幼儿睡眠情况提供适宜的评估工具。 方法 建立条目池,通过头脑风暴法、德尔菲法和预调查对条目进行初筛和修改。采用抽样调查方法,2019年7-11月从全国6个社区、6个乡镇和两家睡眠门诊选择12~35月龄幼儿看护人进行现场调查,共收回有效问卷551份。采用项目分析、效度分析、信度分析、可行性和验证性因子分析对量表进行评价。 结果 幼儿睡眠状况评估量表(12~35个月)包含睡眠节律、夜醒情况、入睡行为、日间嗜睡,睡眠呼吸和异态睡眠6个因子20个条目,累积解释变异量为55.55%。所有条目的内容效度指数介于0.83~1.00。量表入睡潜伏期、夜醒次数、睡眠时间3个条目与简明婴儿睡眠问卷呈正相关(r=0.41、0.69、0.42,P<0.001)。除日间嗜睡外,社区幼儿量表总分以及其他5个因子得分均低于门诊幼儿(P<0.05)。量表总Cronbach's α系数为0.72,两周重测信度为0.84,完成率为92.6%。验证性因子分析结果显示,量表的因子结构模型较为合理、稳定。 结论 量表具有较好的信度效度,可以区分不同幼儿的睡眠状况,有助于及早发现幼儿的睡眠问题。 相似文献
107.
Jong Jin Oh Sangchul Lee Ja Hyeon Ku Tae Gyun Kwon Tae-Hwan Kim Seung Hyun Jeon Sang Hyup Lee Jong Kil Nam Wan Seok Kim Byong Chang Jeong Ji Youl Lee Sung Hoo Hong Koon Ho Rha Woong Kyu Han Won Sik Ham Young Goo Lee Yong Seong Lee Sung Yul Park Young Eun Yoon Sung Gu Kang Seok Ho Kang Korean Robot Assisted Radical Cystectomy Study Group 《BJU international》2021,127(2):182-189
108.
109.
Laura N. Walti Catrina Mugglin Daniel Sidler Matteo Mombelli Oriol Manuel Hans H. Hirsch Nina Khanna Nicolas Mueller Christoph Berger Katia Boggian Christian Garzoni Dionysios Neofytos Christian van Delden Cédric Hirzel Swiss Transplant Cohort Study 《American journal of transplantation》2021,21(7):2532-2542
Posttransplant lymphoproliferative disorder (PTLD) is a serious complication of solid organ transplantation (SOT). Most PTLD cases are associated with Epstein–Barr virus (EBV) infection. The role of antiviral prophylaxis or rituximab therapy for prevention of PTLD in SOT recipients is controversial. In a nationwide cohort, we assessed the incidence, presentation, and outcome of histologically proven PTLD. We included 4765 patients with a follow-up duration of 23 807 person-years (py). Fifty-seven PTLD cases were identified; 39 (68%) were EBV positive (EBV+ PTLD). Incidence rates for EBV+ PTLD at 1, 2, and 3 years posttransplant were 3.51, 2.24, and 1.75/1000 py and 0.44, 0.25, and 0.29/1000 py for EBV− PTLD. We did not find an effect of antiviral prophylaxis on early and late EBV+ PTLD occurrence (early EBV+ PTLD: SHR 0.535 [95% CI 0.199–1.436], p = .264; late EBV+ PTLD: SHR 2.213, [95% CI 0.751–6.521], p = .150). However, none of the patients (0/191) who received a rituximab-containing induction treatment experienced PTLD, but 57 of 4574 patients without rituximab induction developed PTLD. In an adjusted restricted mean survival time model, PTLD-free survival was significantly longer (0.104 years [95% CI 0.077–0.131]) in patients receiving rituximab as induction treatment. This study provides novel data on the association of rituximab induction and reduced risk for PTLD. 相似文献
110.
Cecilia Nakid-Cordero Sylvain Choquet Nicolas Gauthier Noureddine Balegroune Nadine Tarantino Véronique Morel Nadia Arzouk Sonia Burrel Géraldine Rousseau Frédéric Charlotte Martin Larsen Vincent Vieillard Brigitte Autran Véronique Leblond Amélie Guihot for the K-VIROGREF Study Group 《American journal of transplantation》2021,21(8):2846-2863
EBV-positive and EBV-negative posttransplant lymphoproliferative disorders (PTLDs) arise in different immunovirological contexts and might have distinct pathophysiologies. To examine this hypothesis, we conducted a multicentric prospective study with 56 EBV-positive and 39 EBV-negative PTLD patients of the K-VIROGREF cohort, recruited at PTLD diagnosis and before treatment (2013–2019), and compared them to PTLD-free Transplant Controls (TC, n = 21). We measured absolute lymphocyte counts (n = 108), analyzed NK- and T cell phenotypes (n = 49 and 94), and performed EBV-specific functional assays (n = 16 and 42) by multiparameter flow cytometry and ELISpot-IFNγ assays (n = 50). EBV-negative PTLD patients, NK cells overexpressed Tim-3; the 2-year progression-free survival (PFS) was poorer in patients with a CD4 lymphopenia (CD4+<300 cells/mm3, p < .001). EBV-positive PTLD patients presented a profound NK-cell lymphopenia (median = 60 cells/mm3) and a high proportion of NK cells expressing PD-1 (vs. TC, p = .029) and apoptosis markers (vs. TC, p < .001). EBV-specific T cells of EBV-positive PTLD patients circulated in low proportions, showed immune exhaustion (p = .013 vs. TC) and poorly recognized the N-terminal portion of EBNA-3A viral protein. Altogether, this broad comparison of EBV-positive and EBV-negative PTLDs highlight distinct patterns of immunopathological mechanisms between these two diseases and provide new clues for immunotherapeutic strategies and PTLD prognosis. 相似文献