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31.
Acute Cellular Rejection with CD20-Positive Lymphoid Clusters in Kidney Transplant Patients Following Lymphocyte Depletion 总被引:1,自引:0,他引:1
L. K. Kayler F. G. Lakkis C. Morgan A. Basu D. Blisard H. P. Tan J. McCauley C. Wu R. Shapiro P. S. Randhawa 《American journal of transplantation》2007,7(4):949-954
Lymphoid clusters (LC) containing CD20-positive B cells in kidney allografts undergoing acute cellular rejection (ACR) have been identified in small studies as a prognostic factor for glucocorticoid resistance and graft loss. Allograft biopsies obtained during the first episode of ACR in 120 recipients were evaluated for LC, immunostained with CD20 antibody, and correlated with conventional histopathologic criteria, response to treatment and outcome. LC were found in 71 (59%) of the 120 biopsies. All contained CD20 positive B cells that accounted for 5-90% of the LC leukocyte content. The incidence of LC was highest in the patients who had no lymphoid depletion or had been treated with Thymoglobulin preconditioning (79% vs. 75%, respectively) compared to 37% in patients pretreated with Campath (p = 0.0001). Banff 1a/1b ACR were more frequent in the LC-positive than the LC-negative group (96% vs. 80%, respectively; p = 0.0051). With a posttransplant follow-up of 953 +/- 430 days, no significant differences were detected between LC-postitive and LC-negative groups in time to ACR, steroid resistance, serum creatinine and graft loss. CD20+LC did not portend glucocorticoid resistance or worse short to medium term outcomes. CD20+LC may represent a heterogenous collection in which there may be a small still to be fully defined unfavorable subgroup. 相似文献
32.
Eran Maman David M. Steinberg Batia Stark Shai Izraeli Shlomo Wientroub 《Journal of children's orthopaedics》2007,1(1):63-68
Purpose Studies on musculoskeletal manifestations (MSM) of childhood acute lymphoblastic leukemia (ALL) have yielded variable findings
with regard to their clinical impact. We investigated the significance for differential diagnosis, treatment and outcome of
musculoskeletal complaints as presenting symptoms of ALL, and their correlation with leukemia immunophenotypes, for which
data is lacking.
Methods Data on 783 children in the national study for childhood ALL between 1984 and 2003 were reviewed retrospectively. Statistical
analysis examined possible relationships between MSM at the time of diagnosis and demographic and clinical data, biological
features of leukemia (peripheral blood counts, immunophenotype and main cytogenetic aberration), response to initial prednisone
treatment, and outcome.
Results Of 765 children with data on orthopaedic complaints, 240 presented with MSM (31.4%). Among these children, B cell precursor
(BCP) was much more common (209/576, 36.3%) than T cell ALL (25/176, 14.2%). Patients with MSM had lower white blood cell
counts (WBC) (median of 9 vs. 20 × 109/L, P < 0.001) and percentage of blast cells in the peripheral blood at diagnosis compared to those without (median of 27 vs. 53%,
P < 0.001). Hepatomegaly and splenomegaly were less common in MSM group (67 vs. 53% <3 cm, P < 0.001, and 63 vs. 50% <3 cm, P < 0.001, respectively). Poor response to initial treatment with prednisone was recorded in 7.1% of patients with MSM versus
11.5% of those without (P = 0.086). The analysis revealed no independent effect of MSM on event-free survival (EFS), after correcting for differences
in EFS related to immunophenotype or initial WBC.
Conclusions MSM occur mostly in children with BCP ALL who present with less involvement of extramedullary organs, low peripheral blood
blasts and white blood cells counts. These findings highlight the importance of including ALL in the differential diagnosis
of MSM even in the presence of an apparently normal peripheral blood count. Our study also suggests that MSM are caused by
leukemic cells with enhanced biological propensity to remain relatively confined within the intramedullary bone-marrow space. 相似文献
33.
The Hemodynamic Mechanisms of Lung Injury and Systemic Inflammatory Response Following Brain Death in the Transplant Donor 总被引:7,自引:2,他引:5
Vassilios S. Avlonitis Christopher H. Wigfield John A. Kirby John H. Dark 《American journal of transplantation》2005,5(4):684-693
Brain-dead donors are the major source of lungs for transplantation. Brain death is characterized by two hemodynamic phases. Initially, massive sympathetic discharge results in a hypertensive crisis. This is followed by neurogenic hypotension. Up-regulation of pro-inflammatory mediators occurs in all organs and lung injury develops; this can adversely affect graft function post-transplantation. The mechanisms of the systemic and lung inflammation are unknown. We hypothesized that the hemodynamic changes are responsible for these inflammatory phenomena. Brain death was induced by intra-cranial balloon inflation in rats. This resulted in hypertensive crisis, followed by hypotension. There was a significant increase in blood neutrophil CD11b/CD18 expression and pro-inflammatory cytokine levels in serum and bronchoalveolar lavage, compared with control animals. Rupture of the capillary-alveolar membrane was demonstrated by electron microscopy. Elimination of the hypertensive response by α-adrenergic antagonist pre-treatment prevented inflammatory lung injury, reduced the systemic inflammatory markers and preserved capillary-alveolar membrane integrity. Correction of the neurogenic hypotension with noradrenaline ameliorated the systemic inflammatory response and improved oxygenation. We conclude that the sympathetic discharge triggers systemic and lung inflammation, which can be further enhanced by neurogenic hypotension. Management of the brain-dead donor with early anti-inflammatory treatment and vasoconstrictors is warranted. 相似文献
34.
Andr ia Kist Fernandes Felipe Mallmann Ana Maria Pasquali Steinhorst Fernando Lopes Nogueira Eduardo Mü ller vila Dumitriu Zunino Saucedo Francisco Juchem Machado Marcelo Greg rio Raymundi S rgio Saldanha Menna Barreto Paulo de Tarso Roth Dalcin 《The Journal of asthma》2003,40(6):683-690
Asthma patients that depend on emergency department (ED) services are generally considered to have extremely poor disease control and prognosis. It is important to identify characteristics related to poor disease control and frequent visits to the ED to apply appropriate clinical management. This study comprised a cross-sectional survey of consecutive patients with asthma exacerbation (age ≥12 years) presenting at the adult ED of a large, tertiary care, university-affiliated hospital over a 2-month period. The frequent visitors (FV) were defined by ≥3 visits to the ED in the preceding year, and the occasional visitors (OV) by ≤2 visits. Eighty-six patients (61 females and 25 males) were included in the study (mean age 38 ± 18 years). Of these patients, 51.2% were FV and 48.8% were OV. Sixty-nine percent had annual income lower than A$3000 and 66.3% had ≤8 years of the formal education. Only 18.6% had used inhaled corticosteroids, 79.1% identified the asthma attack severity, 70.9% increased or initiated inhaled β-agonist, 20.9% increased or initiated steroid therapy, and 55.8% had an asthma action plan for attack. The number of hospital admissions in past year (OR 4.3, P = .02), use of home nebulizer (OR 3.6, P = .05) and the lack of a written asthma action plan (OR 3.3, P = .03) were independently associated with frequent visits to the ED. We conclude that a substantial proportion of the patients that visit the ED are FV. These patients are more likely to have hospital admission in the past year, to use a home nebulizer, and to lack a written asthma action plan. They should be considered the most important target for asthma education. 相似文献
35.
36.
综合医院医务人员感染SARS情况对比分析 总被引:3,自引:1,他引:2
目的:分析在防治SARS工作初期、后期医务人员感染SARS的差异和采取的对策,为减少综合医院内医务人员SARS的感染提供参考。方甚:对本院自2003年3月24日至6月2日SARS诊断治疗任务中发生的医务人员的感染原因和采取的对策进行回顾性分析。结果:防治SARS工作初期,急诊科交叉感染和在SARS隔离病房等与SARS患者密切接触的工作岗位,共有17名医务人员感染,及时隔离治疗,均已痊愈,未造成医护人员的进一步交叉感染:经加强防护培训,改善工作条件,在防治SARS工作后期,仅发生2名护工感染,亦已痊愈,派出非典医疗队实现零感染。结论:综合医院内医务人员感染SARS的问题严峻,加强医院内的全员防护培训,按岗分区管理,改善医务人员的工作条件和病人的隔离观察环境,做好监督检查,积极应对,可以减少医务人员的SARS感染。 相似文献
37.
本文研究营养性驱铅饮料的动物和人群试验。饮料与铅料动物组间比较,饮料组动物的尿、粪排铅量高,分别是对照组的1.5倍和1.1倍;血、肝、肾中含量低;体内 Zn、Cu、Fe 等微量元素基本稳定。其体重增长与对照组相一致。人群试验:试验组尿铅排出明显,试验末(2月后)仅为试验初的21.7%;血铅平均减少0.39μmol/l;血中 Hb、δ-ALAD 和尿中δ-ALA 等均恢复良好;不影响体内Zn、Cu 等微量元素,无不良反应。 相似文献
38.
汞对人体必需元素干扰的研究 总被引:5,自引:1,他引:4
对42例汞吸收、2例汞中毒者(尿汞>99.7nmol/L),采用原子吸收光谱法,检测了汞对人体必需五种金属元素代谢的干扰。研究发现,汞时人体必需元素镁、铜具有拮抗作用。汞吸收者血清镁极显著低于对照组(P>0.01)。经驱汞治疗后,血清镁、铜自然上升与对照组无统计学差异(P>0.05),镁离子低下,可出现神经肌纤维兴奋性增高。由此推测,汞引起肌肉震颤的毒理,可能由汞拮抗镁离子低下引起。设想,对汞中毒者采用补镁制剂治疗,是否具有驱汞作用值得探讨。 相似文献
39.
应用不同浓度TPA诱发血小板聚集,观察20名正常人血小板的聚集率。结果显示:TPA从5ng/ml到10ng/ml之间,随着浓度的增加,血小板聚集率逐渐增加,最佳浓度为10ng/ml。当TPA浓度〉10mg/ml时,继续增加TPA浓度,血小板聚集率将不再升高,且于20mg/ml时出现明显的解聚现象。 相似文献
40.