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101.
Phosphoinositide 3-kinase is involved in the induction of the human sperm acrosome reaction downstream of tyrosine phosphorylation 总被引:7,自引:4,他引:3
Fisher HM; Brewis IA; Barratt CL; Cooke ID; Moore HD 《Molecular human reproduction》1998,4(9):849-855
In somatic cells phosphoinositide 3-kinase (PI 3-kinase) is activated upon
interaction with both receptor tyrosine kinases (RTK) and G- proteins
resulting in the production of moieties involved in the inositol
phospholipid signalling pathway. As G proteins, RTK and the inositol
phospholipids have all been implicated in the human sperm acrosome
reaction, experiments were carried out to determine whether PI 3-kinase was
also involved in this phenomenon. Wortmannin is a selective inhibitor of PI
3-kinase and was shown to significantly inhibit the acrosome reaction
induced by both mannose-bovine serum albumin (mannose-BSA) (10, 50 and 100
nM) and a polyclonal antibody raised against an extracellular region of the
sperm zona receptor kinase (ZRK, at 100 nM only). Wortmannin did not
inhibit the A23187- or progesterone-induced acrosome reaction. These
results suggest that PI 3- kinase is involved in the human sperm acrosome
reaction. The levels of tyrosine phosphorylation of sperm proteins as
detected by Western blotting using antiphosphotyrosine antibodies was not
affected by wortmannin in agonist (A23187 and mannose-BSA)-stimulated
spermatozoa. This indicated that PI 3-kinase operates downstream of
tyrosine phosphorylation in the signal transduction cascade which leads to
the human sperm acrosome reaction.
相似文献
102.
Influence of age and comorbidity on treatment choice and survival in elderly patients with breast cancer 总被引:3,自引:0,他引:3
Liesbeth Bergman Gert Dekker Elly HM van Kerkhoff Hans L. Peterse Johannes A. van Dongen Flora E. van Leeuwen 《Breast cancer research and treatment》1991,18(3):189-198
Summary To determine the effect of age and comorbid diseases on treatment choice and survival, the medical records of 300 breast cancer patients of 55 years and older were reviewed. All patients were admitted to the Netherlands Cancer Institute (NKI) for first treatment between 1980 and 1987. Patients were classified according to severity level of comorbid diseases. Physicians were found to treat women of 75 years and older less often with adjuvant radiotherapy after a mastectomy, and more often to employ only primary endocrine treatment for local stage disease, as compared with younger patients. According to the treatment guidelines of the institute, the study sample was divided into patients who received standard vs. non-standard treatment. The treatment of 38 women (13.1%) did not correspond with the guidelines. Of these, 84% were 75 years and older and 50% had a severe comorbidity status. Logistic regression analysis indicated that advanced age, per se, was a better indicator of the risk of not being treated according to protocol than the comorbidity status. Cox multivariate analyses demonstrated that neither the severity of the comorbidity status nor the differences in treatment between younger and older patients had a significant effect on the risk of dying from breast cancer or on the risk of developing recurrences. In this analysis, age 75 years or more proved to be a significant and independent predictor of a worse overall and disease-specific survival as compared to age between 65–74 years. 相似文献
103.
104.
105.
Pacemaker Lead Fracture Due to Twiddler's Syndrome 总被引:2,自引:0,他引:2
ÁDÁM BÖHM KATALIN KOMÁROMY ARNOLD PINTÉR ISTVÁN PRÉDA 《Pacing and clinical electrophysiology : PACE》1998,21(5):1162-1163
The authors report a case of pacemaker twiddler's syndrome that led to lead fracture and loss of consciousness. The role of chest X rays in the diagnosis of pacemaker twiddler's syndrome as well as the management of the syndrome is discussed. 相似文献
106.
Progressive platelet activation with storage: evidence for shortened survival of activated platelets after transfusion 总被引:14,自引:0,他引:14
HM Rinder ; M Murphy ; JG Mitchell ; J Stocks ; KA Ault ; RS Hillman 《Transfusion》1991,31(5):409-414
Platelets are known to become activated during storage, but it is unclear whether such activation affects recovery or survival after platelet concentrate (PC) transfusion. With the use of flow cytometry to determine the percentage of platelets expressing the alpha-granule membrane protein 140 (GMP-140), a known adhesive ligand appearing on the platelet surface after activation, several studies were conducted. These investigations evaluated 1) the occurrence of significant platelet activation over time in PCs (n = 46) stored under standard blood bank conditions; 2) the correlation between platelet activation and platelet recovery in normal subjects after PC storage (n = 12), as assessed by the recovery of Indium-labeled platelets; and 3) the recovery of activated and unactivated platelets in thrombocytopenic cancer patients transfused with standard PCs (n = 11). It was determined 1) that an increasing duration of storage of PC was associated with increasing platelet activation as measured by the percentage of platelets expressing GMP-140, progressing from a mean of 4 +/- 2 percent (SD) on the day of collection to a mean of 25 +/- 8 percent by 5 days of storage: 2) that, in normal subjects, posttransfusion recovery of autologous platelets stored for 2 to 4 days and then labeled with In111 was inversely correlated with the percentage of activated platelets in the transfused PC (r = -0.55, p = 0.05); and 3) that, when thrombocytopenic patients were transfused with standard PCs, the recovery of the activated platelets in the transfused PCs averaged only 38 +/- 15 percent of the number predicted by the absolute platelet increment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
107.
细胞移植治疗帕金森病的研究进展 总被引:3,自引:1,他引:3
目的:根据近年细胞移植治疗帕金森病的近况,认识细胞移植治疗帕金森病的最新进展及临床应用前必须解决的技术难题。资料来源:应用计算机检索Pubmed 2000-01/2006-10细胞移植治疗帕金森病的文章,检索词为"Cells transplantation,Parkinson disease",并限定文献种类为English。资料选择:对资料进行初审,选取包括细胞移植与帕金森病相关的文献,开始查找全文。纳入标准:①细胞移植在神经系统疾病中的应用。②细胞移植与帕金森病。排除标准:综述文献、重复研究、Meta分析类文章。资料提炼:共收集到175篇关于细胞移植与帕金森病的文献,纳入30篇文献。资料综合:细胞移植治疗帕金森病的主要细胞来源有肾上腺髓质细胞、胎儿中脑腹侧组织细胞、异种移植、神经干细胞、骨髓干细胞、胚胎干细胞等。其临床应用前仍存在许多技术难题,如移植物的来源、移植部位与方法、移植环境等。随着这些基础研究和临床治疗上难题的解决,细胞移植必将成为治疗帕金森病的重要手段。结论:细胞移植尤其是胚胎干细胞的应用,将为帕金森病的治疗带来新的曙光。 相似文献
108.
Ross AA; Cooper BW; Lazarus HM; Mackay W; Moss TJ; Ciobanu N; Tallman MS; Kennedy MJ; Davidson NE; Sweet D 《Blood》1993,82(9):2605-2610
Although peripheral blood stem cell collections (PBSC) are thought to have less tumor involvement than bone marrow (BM), the incidence of circulating tumor cells in patients with breast cancer has not been widely investigated. We prospectively investigated the incidence and viability of tumor cell involvement in PBSC and BM collections from breast cancer patients undergoing high-dose chemotherapy/hematopoietic stem cell transplantation. Paired samples of PBSC and BM from 48 patients were analyzed using an immunocytochemical technique that detects one epithelial-derived tumor cell per 5 x 10(5) mononuclear cells. Immunostained tumor cells were detected in 9.8% (13/133) PBSC specimens from 9/48 (18.7%) patients and in 62.3% (38/61) BM specimens from 32/48 (66.7%) patients, a significantly higher rate than in PBSC (P < .005). The geometric mean concentration of tumor cells in contaminated PBSC specimens was 0.8/10(5) mononuclear cells (range 0.33 to 2.0/10(5)) compared with 22.9/10(5) mononuclear cells in BM (range 1 to 3,000/10(5), P < .0001). In culture experiments, clonogenic tumor colonies grew in 21/26 immunocytochemically positive specimens. No tumor colony growth was detected in 30/32 immunocytochemically negative specimens. Immunocytochemical detection of tumor involvement in BM and PBSC correlated significantly with in vitro clonogenic growth (P < .0001). We conclude that PBSC contain fewer tumor cells than paired BM specimens from patients with advanced breast cancer and that these tumor cells appear to be capable of clonogenic growth in vitro. 相似文献
109.
IgG4‐related disease (IgG4‐RD) has emerged as a new entity in the last decade. It comprises numerous conditions previously thought to be unrelated. Macroscopically, these diseases cause diffuse organ swelling and formation of pseudotumorous masses. Histopathologically, they are characterized by a lymphoplasmacytic infiltrate with increased IgG4+ plasma cells and storiform fibrosis. Despite rapid progress within the last years, our knowledge on these conditions is still fragmented. To date, more than forty organs have been reported to be included in IgG4‐RD, and salivary gland involvement is amongst the most common organs affected [IgG4‐related sialadenitis (IgG4‐RS)]. Interestingly, IgG4‐RS shares commonalities with Sjögren's syndrome (SS), like glandular enlargement, sicca symptoms, arthralgias, hypergammaglobulinemia, hypocomplementemia, and circulating antinuclear antibodies. Nonetheless, they differ in that the incidence of anti‐Ro and anti‐La reactivity is not frequently found in patients with IgG4‐RS, their salivary glands are infiltrated by a large number of IgG4+ plasma cells and IgG4‐RS symptoms respond promptly to steroids. The aim of this review was to describe the clinical, serological, histopathological and pathophysiological aspects of IgG4‐RS in the context of IgG4‐RD and highlight the differences between IgG4‐RS and SS. 相似文献
110.
Treatment of progressive Hodgkin's disease with intensive chemoradiotherapy and autologous bone marrow transplantation 总被引:2,自引:0,他引:2
Phillips GL; Wolff SN; Herzig RH; Lazarus HM; Fay JW; Lin HS; Shina DC; Glasgow GP; Griffith RC; Lamb CW 《Blood》1989,73(8):2086-2092
Twenty-six patients with progressive Hodgkin's disease after conventional chemotherapy received intensive chemoradiotherapy and autologous bone marrow transplantation (ABMT); 19 also received additional involved-field radiotherapy. Twenty-one patients [81%, 95% confidence intervals (CI) 61% to 94%] attained complete (n = 18) or partial responses. Ten patients (38%, 95% CI 20% to 59%) are disease- free a median of 4.5 years later (range 3.5 to 7.0 years), including seven patients with continuous complete responses. The likelihood of overall response was not significantly influenced by any clinical or treatment variable examined. However, there was a trend favoring patients with higher Karnofsky scores, and higher scores were associated with attainment of complete responses (P = .06 and P = .02, respectively, Mann-Whitney U test). Both higher Karnofsky scores and shorter durations of disease before transplantation were associated with improved survival in a stepwise Cox multivariate analysis. The chief cause of failure was progression at sites previously involved with Hodgkin's disease. No patient relapsed in the marrow, and two of three patients with a history of marrow involvement with Hodgkin's disease achieved durable complete responses after transplantation. These data suggest that inadequate pretransplant conditioning, and not the reinoculation of occult tumor cells in the autologous marrow, caused most relapses. Fatal treatment-related toxicity occurred in six patients. Three patients died of idiopathic interstitial pneumonitis; each had previously received local mediastinal irradiation before intensive chemoradiotherapy. Intensive chemoradiotherapy and ABMT produces durable responses in some patients with Hodgkin's disease incurable with conventional therapy. Use of such therapies at the first sign of failure with conventional chemotherapy and development of more effective conditioning regimens should further improve results. 相似文献