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101.
Evidence for a role for Galphai1 in mediating weak agonist-induced platelet aggregation in human platelets: reduced Galphai1 expression and defective Gi signaling in the platelets of a patient with a chronic bleeding disorder 总被引:2,自引:0,他引:2 下载免费PDF全文
Patel YM Patel K Rahman S Smith MP Spooner G Sumathipala R Mitchell M Flynn G Aitken A Savidge G 《Blood》2003,101(12):4828-4835
We have examined platelet functional responses and characterized a novel signaling defect in the platelets of a patient suffering from a chronic bleeding disorder. Platelet aggregation responses stimulated by weak agonists such as adenosine diphosphate (ADP) and adrenaline were severely impaired. In comparison, both aggregation and dense granule secretion were normal following activation with high doses of collagen, thrombin, or phorbol-12 myristate-13 acetate (PMA). ADP, thrombin, or thromboxane A2 (TxA2) signaling through their respective Gq-coupled receptors was normal as assessed by measuring either mobilization of intracellular calcium, diacylglycerol (DAG) generation, or pleckstrin phosphorylation. In comparison, Gi-mediated signaling induced by either thrombin, ADP, or adrenaline, examined by suppression of forskolin-stimulated rise in cyclic AMP (cAMP) was impaired, indicating dysfunctional Galphai signaling. Immunoblot analysis of platelet membranes with specific antiserum against different Galpha subunits indicated normal levels of Galphai2,Galphai3,Galphaz, and Galphaq in patient platelets. However, the Galphai1level was reduced to 25% of that found in normal platelets. Analysis of platelet cDNA and gDNA revealed no abnormality in either the Galphai1 or Galphai2 gene sequences. Our studies implicate the minor expressed Galphai subtype Galphai1 as having an important role in regulating signaling pathways associated with the activation of alphaIIbbeta3 and subsequent platelet aggregation by weak agonists. 相似文献
102.
Interleukin-11 stimulates multilineage progenitors, but not stem cells, in murine and human long-term marrow cultures 总被引:3,自引:0,他引:3
Interleukin-11 (IL-11) is a bone marrow microenvironment-derived growth factor with pleiotropic effects on a variety of hematopoietic cells. To more accurately assess the effects of IL-11 on stem and progenitor compartments within the hematopoietic microenvironment (HM), we added recombinant human (rh) IL-11 to human and murine long-term bone marrow cultures (LTMC) and analyzed primitive (high proliferative potential- colony forming cells [HPP-CFC], long-term culture-initiating cells [LTC- IC], and long-term reconstituting stem cells) and progenitor (day 12 colony forming unit-spleen [CFU-S12], colony forming unit-megakaryocyte [CFU-Mk] and colony forming unit-granulocyte/macrophage [CFU-GM]) compartments throughout the duration of the cultures. rhIL-11 (100 ng/mL) added twice weekly resulted in significantly increased nonadherent (NA) cellularity, CFU-GM, and CFU-Mk production in human LTMC. Addition of rhIL-11 to murine LTMC was associated with a 5- to 40- fold increase in CFU-GM and a four- to 20-fold increase in day 12 CFU-S in NA cells. However, IL-11 had no significant effect on total HPP-CFC concentration and decreased the size of the more primitive stem/progenitor compartment as evidenced by both decreased LTC-IC frequency in human LTMC and decreased frequency of long-term reconstituting stem cells in murine LTMC. These data suggest that IL-11 may increase commitment of stem cells into a multipotential progenitor compartment. 相似文献
103.
Acquired immune hemolytic anemia associated with IgA erythrocyte coating: investigation of hemolytic mechanisms 总被引:1,自引:0,他引:1
We have investigated the hemolytic mechanisms in a patient with acquired immune hemolytic anemia whose red cells appeared to be coated with IgA alone. The clinical course was similar to that of patients with hemolytic anemia mediated by warm-reacting IgG antibody. Splenic sequestration of red cells was demonstrated, and marked reduction of hemolysis occurred after corticosteroid therapy. Antibody was eluted from the patient's red cells and used to sensitize normal red cells in vitro. These sensitized red cells were not lysed by fresh autologous serum, nor did they fix detectable amounts of C3. However, red cells sensitized by eluted antibody were lysed by normal human peripheral blood monocytes in a system designed to demonstrate antibody-dependent cell-mediated cytotoxicity. Monocyte-mediated hemolysis of sensitized red cells was inhibited by the addition of low concentrations of normal serum IgA to the system, but not by IgG. The ability of the eluate to induce monocyte-mediated hemolysis was abolished by its adsorption on Sepharose-bound anti-IgA, but not by preincubation with Sepharose-bound anti-IgG. In addition, normal human monocytes were demonstrated to ingest eluate-sensitized red cells. These data demonstrate an in vitro interaction of IgA-sensitized red cells with leukocytes and suggest a possible mechanism for the patient's hemolysis. 相似文献
104.
Nongnuj Tanphaichitr Kessiri Kongmanas Hathairat Kruevaisayawan Arpornrad Saewu Clarissa Sugeng Jason Fernandes Puneet Souda Jonathan B Angel Kym F Faull R John Aitken Julian Whitelegge Daniel Hardy Trish Berger Mark Baker 《Asian journal of andrology》2015,17(4):574-582
The interaction of sperm with the egg''s extracellular matrix, the zona pellucida (ZP) is the first step of the union between male and female gametes. The molecular mechanisms of this process have been studied for the past six decades with the results obtained being both interesting and confusing. In this article, we describe our recent work, which attempts to address two lines of questions from previous studies. First, because there are numerous ZP binding proteins reported by various researchers, how do these proteins act together in sperm–ZP interaction? Second, why do a number of acrosomal proteins have ZP affinity? Are they involved mainly in the initial sperm–ZP binding or rather in anchoring acrosome reacting/reacted spermatozoa to the ZP? Our studies reveal that a number of ZP binding proteins and chaperones, extracted from the anterior sperm head plasma membrane, coexist as high molecular weight (HMW) complexes, and that these complexes in capacitated spermatozoa have preferential ability to bind to the ZP. Zonadhesin (ZAN), known as an acrosomal protein with ZP affinity, is one of these proteins in the HMW complexes. Immunoprecipitation indicates that ZAN interacts with other acrosomal proteins, proacrosin/acrosin and sp32 (ACRBP), also present in the HMW complexes. Immunodetection of ZAN and proacrosin/acrosin on spermatozoa further indicates that both proteins traffic to the sperm head surface during capacitation where the sperm acrosomal matrix is still intact, and therefore they are likely involved in the initial sperm–ZP binding step. 相似文献
105.
目的对比高黏度与低黏度骨水泥经皮椎体后凸成形术(PKP)治疗骨质疏松性椎体压缩性骨折(OVCF)的疗效差异。方法将2013年3月至2014年9月高要市人民医院收治的60例OVCF患者采用随机抽签法分为低黏度组(低黏度骨水泥PKP治疗)和高黏度组(高黏度骨水泥PKP治疗),每组各30例。对比两组手术前后伤椎椎体高度和后凸Cobb角;采用视觉模拟量表(VAS)评分、Oswestry功能障碍指数(ODI)、36项健康调查简表(SF-36)评分对患者疼痛程度、功能障碍和生活质量等主观感受进行评价;统计骨水泥渗漏、近期肺栓塞等并发症发生情况。结果低黏度组和高黏度组骨水泥注入量分别为(3.1±0.6)m L和(3.6±0.8)m L,两组比较,差异有统计学意义(P0.05)。术后随访3~6个月(平均4个月),两组术后1 d、3个月VAS评分、ODI、SF-36评分、伤椎椎体高度和后凸Cobb角均优于术前(P0.05),其中高黏度组术后1 d、3个月上述指标均优于低黏度组(P0.05)。低黏度组和高黏度组术后发生骨水泥渗漏、近期肺栓塞分别为6、2例和1、0例,两组并发症发生率比较,差异有统计学意义(P0.05)。结论与低黏度骨水泥比较,高黏度骨水泥PKP治疗OVCF近期疗效更为理想,骨水泥渗漏、近期肺栓塞等并发症发生率相对较低,值得临床推广应用。 相似文献
106.
Montserrat Reyes Gonzalo Rojas-Alcayaga Andrea Maturana Juan-Pablo Aitken Carolina Rojas Ana-Verónica Ortega 《Medicina oral, patología oral y cirugía bucal》2015,20(5):e540-e546
Background
Deregulation of ?-catenin is associated with malignant transformation; however, its relationship with potentially malignant and malignant oral processes is not fully understood. The aim of this study was to determine and compare the nuclear ?-catenin expression in oral dysplasia and oral squamous cell carcinoma (OSCC).Material and Methods
Cross sectional study. Immunodetection of ?-catenin was performed on 72 samples, with the following distribution: 21 mild dysplasia, 12 moderate dysplasia, severe dysplasia 3, 36 OSCC including 19 well differentiated, 15 moderately differentiated and 2 poorly differentiated. Through microscopic observation the number of positive cells per 1000 epithelial cells was counted. For the statistical analysis, the Kruskal Wallis test was used.Results
Nuclear expression of ?-catenin was observed in all samples with severe and moderate dysplasia, with a median of 267.5, in comparison to mild dysplasia whose median was 103.75. Only 10 samples (27.7%) with OSCC showed nuclear expression, with statistically significant differences between groups (p < 0.05).Conclusions
Our results are consistent with most of the reports which show increased presence of ?-catenin in severe and moderate dysplasia compared to mild dysplasia; however the expression of nuclear ?-catenin decreased after starting the invasive neoplastic process. This suggests a role for this protein in the progression of dysplasia and early malignant transformation to OSCC. Immunodetection of ?-catenin could be a possible immune marker in the detection of oral dysplasia. Key words:Oral squamous cell carcinoma (OSCC), ?-catenin, oral dysplasia. 相似文献107.
Lung cancers in children under the age of 15 are very uncommon, with a scarcity of literature describing patient characteristics and survival. This study assessed first primary malignant cancers occurring in the trachea, bronchus, or lung (International Classification of Diseases for Oncology, 3rd edition [ICD‐O‐3] codes C33‐C34) for the period 1983‐2015, using data from the population‐based Australian Childhood Cancer Registry. Variables of interest included morphology, sex, age group, and metastatic status at diagnosis. Mode of treatment was also assessed where possible. The Kaplan‐Meier method was used to calculate 5‐year observed survival. Of the 53 in‐scope patients, almost half (n = 23, 43%) were diagnosed with pleuropulmonary blastoma and a further 8 (15%) had a carcinoid tumor. Few of the patients with details available on stage at diagnosis (n = 7 of 43, 16%) presented with metastatic disease. Surgical excision was the most common treatment (30 of 37 children, 81%), with two‐thirds (n = 28 of 43, 65%) receiving chemotherapy. Five‐year observed survival was estimated to be 74% (95% CI = 61%‐85%). Our results represent one of the largest and most complete population‐based cohorts of children with primary malignant lung cancers available to date. Detection of childhood lung cancer can be difficult due to the rarity of this disease and symptoms that are typically nonspecific. 相似文献
108.
目的 探讨改良颈腮腺入路在高位咽旁间隙良性肿瘤手术中的应用疗效。 方法 7例咽旁间隙良性肿瘤患者,术前影像学检查提示为高位、肿瘤巨大、哑铃型且边界欠清,采用改良颈腮腺入路术式,解剖辨认面神经总干及颞面干后,于外耳道软骨前方、腮腺的后缘以及颞面干的上方间隙向深部分离至肿瘤上极,剥离子分离并下压肿瘤与下方常规颈部自下而上肿瘤游离会师后,从颌下区取出肿瘤。腮腺浅叶不切除,面神经分支不做过多解剖。 结果 所有患者均一次性完整切除肿瘤;术后病理示多形性腺瘤6例,神经鞘瘤1例;术中出血均少于300 mL;1例患者出现术后同侧眼睑轻度闭合障碍,两周后完全正常;所有患者面容美学保存理想。 结论 对于高位咽旁间隙良性肿瘤采用改良颈腮腺入路术式,不仅可以安全完整地切除肿瘤,同时由于减少了面神经及腮腺浅叶的处置,术后相关神经并发症及腮腺区凹陷性改变的发生率下降。 相似文献
109.
110.
AP Mishreki E Lim P Cranefield S Pascoe S Jackson DA Stell 《Annals of the Royal College of Surgeons of England》2013,95(5):349-352