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921.
Phosphatidylinositol 3-kinase associates, via its Src homology 2 domains, with the activated erythropoietin receptor 总被引:8,自引:2,他引:8
The erythropoietin receptor (EpR) belongs to a family of hematopoietin receptors whose members lack tyrosine kinase activity. Nonetheless, within minutes of binding Ep, a number of cellular proteins become transiently phosphorylated on tyrosine residues. One of these proteins, as we and others have shown previously, is the EpR itself. To identify the remaining protein substrates, we have examined the antiphosphotyrosine immunoprecipitates of lysates from Ba/F3 cells expressing high levels of cell surface EpRs. We now present data showing that, in response to Ep, the 85-Kd regulatory subunit of phosphatidylinositol 3-kinase (PI 3-kinase) becomes immunoprecipitable with antiphosphotyrosine antibodies. This appears to be due, in large part, to the specific association of PI 3-kinase with the tyrosine- phosphorylated EpR, either directly or through a 93- or 70-Kd tyrosine- phosphorylated intermediate. The activity of this EpR associated PI 3- kinase, assessed in anti-EpR immunoprecipitates, is maximal within 2 minutes of incubation with Ep and returns almost to baseline levels by 10 minutes. In vitro studies suggest that the interaction between PI 3- kinase and the activated EpR is mediated by the N- and C-terminal SH2 domains of p85 and tyrosine-phosphorylated motifs on the EpR. 相似文献
922.
C Bandala AL Cortés-Algara CM Mejía-Barradas I Ilizaliturri-Flores R Dominguez-Rubio CI Bazán-Méndez E Floriano-Sánchez JP Luna-Arias M Anaya-Ruiz E Lara-Padilla 《International journal of clinical and experimental pathology》2015,8(7):8411-8418
Aim: It is known that botulinum neurotoxin type A (BoNTA) improves some kinds of cancer (e.g. prostate) and that synaptic vesicle glycoprotein 2 (SV2) is the molecular target of this neurotoxin. Besides having potential therapeutic value, this glycoprotein has recently been proposed as a molecular marker for several types of cancer. Although the mechanisms of cancer development and the improvement found with botulinum treatment are not well understood, the formation of the botulinum-SV2 complex may influence the presence and distribution of SV2 and the function of vesicles. To date, there are no reports on the possible effect of botulinum on breast cancer of unknown causes, which have a great impact on women’s health. Thus we determined the presence of SV2 in three breast cancer cell lines and the alterations found with botulinum application. Materials and methods: With and without adding 10 units of botulinum, SV2 protein expression was determined by optical densitometry in T47D, MDA-MB-231 and MDA-MB-453 cell lines and the distribution of SV2 was observed with immunochemistry (hematoxylin staining). Results: The SV2 protein was abundant in the cancer cells herein tested, and maximally so in T47D. In all three cancer cell lines botulinum diminished SV2 expression, which was found mostly in the cell periphery. Conclusion: SV2 could be a molecular marker in breast cancer. Its expression and distribution is regulated by botulinum, suggesting an interesting control mechanism for SV2 expression and a possible alternative therapy. Further studies are needed in this sense. 相似文献
923.
阿里·奥·牛麦瑞 《中国烧伤创疡杂志》2012,24(4):285-293
[概述]创面生理性愈合仍是当今国际医学界的一个棘手问题.目前, 创面处理的方法随着细胞生物学与生物活性因子学的发展发生了根本性变化, 对创面愈合机理也有了更深入的研究.创面形成的原因包括外源性损伤因素, 如急、慢性机械性损伤, 物理性或化学性烧伤, 冻疮, 感染或毒素, 内源性损伤因素如基因变异、血管病变、自身免疫性疾病、代谢紊乱、癌变或身心疾病等. 相似文献
924.
Kathleen Puntillo Shoshana R. Arai Bruce A. Cooper Nancy A. Stotts Judith E. Nelson 《Intensive care medicine》2014,40(9):1295-1302
Purpose
To test an intervention bundle for thirst intensity, thirst distress, and dry mouth, which are among the most pervasive, intense, distressful, unrecognized, and undertreated symptoms in ICU patients, but for which data-based interventions are lacking.Methods
This was a single-blinded randomized clinical trial in three ICUs in a tertiary medical center in urban California. A total of 252 cognitively intact patients reporting thirst intensity (TI) and/or thirst distress (TD) scores ≥3 on 0–10 numeric rating scales (NRS) were randomized to intervention or usual care groups. A research team nurse (RTN#1) obtained patients’ pre-procedure TI and TD scores and reports of dry mouth. She then administered a thirst bundle to the intervention group: oral swab wipes, sterile ice-cold water sprays, and a lip moisturizer, or observed patients in the usual care group. RTN#2, blinded to group assignment, obtained post-procedure TI and TD scores. Up to six sessions per patient were conducted across 2 days.Results
Multilevel linear regression determined that the average decreases in TI and TD scores from pre-procedure to post-procedure were significantly greater in the intervention group (2.3 and 1.8 NRS points, respectively) versus the usual care group (0.6 and 0.4 points, respectively) (p < 0.05). The usual care group was 1.9 times more likely than the intervention group to report dry mouth for each additional session on day 1.Conclusion
This simple, inexpensive thirst bundle significantly decreased ICU patients’ thirst and dry mouth and can be considered a practice intervention for patients experiencing thirst. 相似文献925.
Saeed AL Ahmari Ahmed Amro Mohammed AL Otabi Moheeb AL Abdullah Saad AL Kasab Husien AL Amri 《Journal of the Saudi Heart Association》2012,24(1):23-27
Background and aimsBMV is an established treatment for rheumatic mitral valve stenosis. The procedure is historically guided by fluoroscopy, and the role of intracardiac echocardiogram (ICE) guidance is not well defined. We report our initial experience of using ICE to guide BMV procedures.MethodsDuring BMV procedure, ICE catheter was inserted into the right atrium from the right femoral vein, and the septal puncture was monitored by ICE, as well as positioning of the balloon in the mitral valve. Comparisons were made between ICE, transthoracic echocardiography (TTE), and catheterization derived hemodynamic measurements (cath).ResultsSeventeen patients with mitral stenosis underwent the procedure. The mean age was 44.4 ± 21 years. The mean MV area increased from 0.9 ± 0.1 cm2 to 1.7 ± 0.2 cm2, P < 0.0001 and the mean gradient decreased from 12.6 ± 5.8 mmHg to 4.9 ± 1.8 mmHg, P < 0.001. Atrial septum puncture and guidance of the balloon into the MV apparatus were obtained in all patients under ICE guidance. Severe MR developed in one patient and was readily detected by ICE. ICE derived gradient measurements were comparable to those obtained by TTE, and cath.ConclusionICE guidance of BMV is feasible, and useful in monitoring safe septal puncture, optimizing balloon positioning, and in detecting complications. The hemodynamic measurements obtained were comparable to those obtained by TTE, and cath. 相似文献
926.
Women participants of two federally administered nutrition education programs (n=149, 56% white, 64% food secure, 86% 18-50 years of age,) completed telephone interviews that included three 24-hour dietary recalls and the Satter Eating Competence Inventory. Eating competence is delineated by an Inventory score≥32. Competent eaters had significantly greater intakes of fiber, vitamin A, vitamin E, vitamin C, most B-vitamins, magnesium, iron, zinc, potassium and a higher Healthy Eating Index. Two dietary patterns defined as Prudent and Western were observed. The Prudent pattern was correlated with eating competence and characterized by more healthful foods such as fruits, vegetables and low-fat dairy products. The Western pattern, characterized by foods higher in fat, salt, and sugar, was not related to eating competence. Findings suggest that dietary guidance using an eating competence approach for low-income women is compatible with goals to improve dietary quality and eating patterns. 相似文献
927.
Human T-lymphotropic virus type I and type II infections and correlation with risk factors in blood donors from Sao Paulo, Brazil 总被引:2,自引:0,他引:2
OC Ferreira Junior ; RS Vaz ; MB Carvalho ; C Guerra ; AL Fabron ; J Rosemblit ; N Hamerschlak 《Transfusion》1995,35(3):258-263
BACKGROUND: Little is known about the prevalence of and risk factors for human T-lymphotropic virus type I and type II (HTLV-I, HTLV-II) infections in Brazil. STUDY DESIGN AND METHODS: Sera from 17,063 healthy Brazilian donors were screened by enzyme-linked immunosorbent assay for antibody to HTLV-I/II between August 1991 and July 1993. Repeatedly reactive samples were confirmed by Western blot, and discrimination between HTLV-I and HTLV-II was made by polymerase chain reaction or synthetic peptide enzyme-linked immunosorbent assay. A univariate analysis was performed on demographic and serologic data. RESULTS: HTLV-I infection was demonstrated in 83 percent of the 30 donors with reactive serologic tests (0.15% of the total tested [17,063]; 95% CI, 0.09-0.20) and HTLV-II infection in 17 percent (0.03% of the total tested [17,063]; 95% CI, 0.01-0.05). HTLV-I-positive donors were more likely than reference groups to be of Asian ethnicity (odds ratio [OR] 15.1; reference group: whites), more than 50 years old (OR 4.2; reference group: 20–29 years old), and positive for antibody to hepatitis C virus (anti-HCV) (OR 21.8) or to hepatitis B core (antigen) (anti-HBc) (OR 5.7). HTLV-II showed a significant association with anti-HCV (OR 75.2) and anti-HBc (OR 21.8). Eleven of the 25 HTLV-I- positive donors were counseled. Family origin in endemic areas of Japan (n = 4), prior blood transfusion (n = 3), or sexual contact with prostitutes (n = 1) were the risk factors reported by 8 donors. In 3 white men, no risk factors could be identified. CONCLUSION: Both HTLV-I and HTLV-II occur among Brazilian blood donors. HTLV-I is associated with Asian ethnicity, greater age, and the presence of anti-HCV and anti-HBc. Three HTLV-I-positive donors had a history of blood transfusion, which emphasizes the need for HTLV-I/II screening in Brazil. 相似文献
928.
Haemodynamic parameters predicting variceal haemorrhage and survival in alcoholic cirrhosis 总被引:1,自引:0,他引:1
Stanley AJ; Robinson I; Forrest EH; Jones AL; Hayes PC 《QJM : monthly journal of the Association of Physicians》1998,91(1):19-25
The relationship between the various haemodynamic abnormalities observed in
cirrhosis and their prognostic value remains unclear. We report
haemodynamic measurements on 96 patients with alcoholic cirrhosis (mean
Childs-Pugh Score, CPS, 9.0 +/- 0.2, mean age 55.6 +/- 1.0 years) and
assess their value in predicting variceal bleeding and death during a mean
follow-up of 19.3 +/- 1.5 months. Baseline CPS correlated with hepatic
venous pressure gradient (HVPG) (p = 0.001), azygos blood flow (p <
0.05), cardiac index (p < 0.05), and inversely with mean arterial
pressure (p < 0.01) and systemic vascular resistance index (p <
0.05). Renal blood flow was not related to any haemodynamic parameter or
CPS. Thirty-eight patients died during follow-up, and 16 had a variceal
bleed. Death (p = 0.001) and variceal bleeding (p < 0.05) were more
likely in patients with HVPG > 16 mmHg than in those with HVPG < 16
mmHg, and variceal bleeding was more likely in patients with HVPG > 12
mmHg (vs. HVPG < 12 mmHg, p < 0.05). HVPG also predicted death and
variceal haemorrhage on univariate and multivariate analyses. No other
haemodynamic parameter predicted death or bleeding. In alcoholic cirrhosis,
severity of liver disease is related to HVPG, collateral blood flow and
degree of systemic circulatory abnormalities. HVPG is a useful predictor of
survival and variceal bleeding in these patients.
相似文献
929.
Specific antibodies to Trypanosoma cruzi among blood donors in Los Angeles, California 总被引:1,自引:0,他引:1
BACKGROUND: Trypanosoma cruzi, the cause of Chagas' disease, is often transmitted by transfusion in Latin America. Previous studies showed that at least 1 in 1000 eligible blood donors at the Los Angeles County+University of Southern California (LAC+USC) Medical Center Blood Bank had specific antibodies to T. cruzi. In June 1993, serologic screening of prospective allogeneic donors at epidemiologic risk for T. cruzi infection was begun voluntarily. STUDY DESIGN AND METHODS: The risk of T. cruzi infection in all eligible donors was assessed by questionnaire. At-risk donors were screened serologically for antibodies to T. cruzi with an enzyme immunoassay, and confirmatory testing was done with a radioimmunoprecipitation assay. RESULTS: During the 29-month study period 1311 (39.5%) of 3320 donors were judged to be at risk for T. cruzi infection. Seven donors (1/475) were reactive by an enzyme immunoassay, and six of these seven (1/ 553) were positive in a radioimmunoprecipitation assay. All radioimmunoprecipitation assay- positive donors had been born in countries in which Chagas' disease is endemic. One person in this group had received a transfusion in his homeland. CONCLUSION: These results demonstrate that a substantive proportion of eligible blood donors at our institution have antibodies specific for T. cruzi and that a commercially available assay can be used to detect these antibodies. Our data suggest that the risk of transmission of T. cruzi by transfusion could be eliminated by serologic testing limited to persons born in or transfused in countries in which Chagas' disease is endemic. 相似文献
930.
HLA antigens in Omani patients with vitiligo 总被引:7,自引:0,他引:7
M.N. VENKATARAM A.G. WHITE W.A. LEENY A.R.AL. SUWAID A.S. DAAR 《Clinical and experimental dermatology》1995,20(1):35-37
Fifty native Omanis with vitiligo were studied to compare the incidence of HLA ABC and DR antigens with a control population. HLA Bw6 was found in 82% of patients compared with 49% controls (Pc= 0.0009 RR = 4.56) and HLA DR7 occurred in 40% of patients and 9% in controls (Pc= 0.00075 RR = 6.17). HLA DR7 was significantly increased in those patients with acrofacial, compared to focal disease (57% vs. 24%P= 0.038). Sixty-six per cent of the patients in this study had parents who were consanguineous and a positive family history was only found in this group with an incidence of 32%. HLA Bw4 segregated 100% with patients with a positive family history compared with 48% in consanguineous patients without a positive family history (Pc= 0.011 RR = 23). Vitiligo appears to be associated with different HLA antigens in different ethnic groups. 相似文献