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Fotios A. Asimakopoulos Nicholas J. White Elisabeth P. Nacheva & Anthony R. Green 《British journal of haematology》1995,92(1):127-130
Deletions of chromosome 20q are associated with myeloid malignancies and have been previously shown to arise in a multipotent progenitor of both myeloid and B cells. However, B-cell differentiation from the abnormal progenitor was impaired. The CD40 antigen is a surface glycoprotein which is expressed in B cells and haemopoietic stem cells and is important for B-cell growth and development. Following the recent mapping of CD40 to chromosome 20q we sought to determine its position relative to 20q deletions. Analysis of lymphoblastoid cell lines carrying 20q deletions placed CD40 within a 19–21 cM interval which is almost coincidental with the common deleted region defined by previous analysis of patient samples. Our results raise the possibility that genetic alteration of this locus may contribute to the pathogenesis of myeloid disorders associated with 20q deletions. 相似文献
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Byron Asimakopoulos Aggeliki Tiptiri-Kourpeti Chrysa Metallinou 《Reproductive Medicine and Biology》2021,20(3):361-367
Purpose
Progressive motility (PM) and vitality are positively associated with fertilization ability of spermatozoa. Here, the effects of IGF-I and NGFβ on PM and vitality of human spermatozoa were investigated.Methods
Forty-three volunteers gave semen samples after 2-3 days of sexual abstinence. Each sample was processed with density gradient centrifugation and sperm washing. The pellet was divided into 3 aliquots. An aliquot containing one million of progressively motile spermatozoa was incubated for an hour (37°C) in standard culture medium (control group), and two aliquots with the same number of progressively motile spermatozoa were incubated in medium supplemented with IGF-I or NGFβ. Two concentrations of IGF-I (100 ng/ml and 1000 ng/ml) and NGFβ (0,5 ng/ml and 5 ng/ml) were tested.Results
Both growth factors significantly increased PM and vitality in comparison with control either at the low or the high concentration. IGF-I seemed to be more effective than NGFβ. The effects did not seem to be dose dependent with the exception of the effect of IGF-I on vitality.Conclusions
The enhancement of PM and vitality of human spermatozoa by IGF-I and NGFβ opens new ways for the improvement of sperm processing. Further research is needed to determine the most effective concentrations.4.
Asimakopoulos G Kohn A Stefanou DC Haskard DO Landis RC Taylor KM 《The Annals of thoracic surgery》2000,69(4):1192-1197
BACKGROUND: The recruitment of leukocytes to vascular endothelium is controlled by adhesion events mediated through the beta2 integrins, whereas the response of extravasated leukocytes within the tissues is controlled through the beta1 integrins. Although cardiopulmonary bypass (CPB) has been shown to be associated with a systemic inflammatory response and elevated levels of beta2 integrins on leukocytes, its effect on the beta1 integrins is not known. This study investigated the effect of the protease inhibitor aprotinin on the expression of the beta1 and beta2 integrins on circulating leukocytes in patients undergoing CPB. METHODS: Patients undergoing primary elective coronary artery bypass grafting were randomized into full-dose aprotinin or placebo groups. Blood samples were obtained at nine time points preoperatively, intraoperatively, and up to 6 days postoperatively. The surface expression of the beta1 integrins VLA-1, -3, -4, -5, and -6 and of the beta2 integrins CD11a/CD18, CD11b/CD18, and CD11c/CD18 was measured by flow cytometry on gated neutrophil and monocyte subpopulations in whole blood. RESULTS: Expression of the beta1 integrins was not significantly altered during the study period and, therefore, aprotinin had no effect on the expression of these molecules. Of the beta2 integrins, CD11b/CD18 expression was significantly increased on neutrophils at 15 minutes after onset of CPB in the placebo group (p < 0.01) but not in the aprotinin group. CONCLUSIONS: This study showed that expression of the beta1 integrins on neutrophils and monocytes did not alter during the first 6 days after CPB. Expression of the beta2 integrin CD11b/CD18 increased significantly on neutrophils during CPB in control patients but not in patients treated with full-dose aprotinin. 相似文献
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Charalampos Milionis MD 《Nursing philosophy》2013,14(1):17-27
Both healthcare professionals and the healthcare system must defend each patient's health individually while simultaneously seeking to protect the population's health in general. Nowadays, there is an important increase in the cost of healthcare supply, mainly due to the developments of medical science, the public's expectations and the demographic ageing. Since healthcare resources are not unlimited, it is obvious that immoderate consumption of them by certain patients limits the use of the same funds by others. Therefore, we have to seek an optimal distribution of the existing resources in order to manage a constriction of expenses, especially under the circumstances of the modern economic crisis. The criteria of effectiveness and efficiency should be used. Health policies focus on both the public's behaviour and the rules of medical practice. Under the modern challenges the physician's role is particularly important for the protection of the patient's health and the promotion of public health. 相似文献
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Stamatis Karakonstantis Emmanouil Tzagkarakis Dimitra Kalemaki Charalampos Lydakis Gregorios Paspatis 《Expert Review of Gastroenterology & Hepatology》2018,12(1):63-72
Introduction: The usefulness of nasogastric aspiration and nasogastric lavage in patients with gastrointestinal bleeding is controversial, as evidenced by conflicting recommendations, both among and within society guidelines.Areas covered: Considering these controversies, we reviewed the evidence regarding the following questions: 1) Can nasogastric lavage stop or slow down the bleeding and improve subsequent endoscopic visualization? 2) Is nasogastric aspiration helpful for the localization of bleeding? 3) Can nasogastric aspiration identify high risk patients that might benefit from earlier endoscopy? 4) Is there evidence for benefit in terms of outcomes from using nasogastric aspiration? 5) Is nasogastric intubation safe in patients with possible esophageal varices? Our review was conducted according to PRISMA guidelines.Expert commentary: Based on the available literature, nasogastric lavage or aspiration cannot be routinely recommended unless a large properly designed randomized trial (which is currently lacking) proves otherwise. It is a painful and time-consuming procedure with no demonstrated benefit for the patient in terms of outcomes. Other clinical and laboratory parameters, and risk scores, are less invasive and are effective for guiding the stratification and management of patients, while pre-endoscopic erythromycin infusion is a good if not better alternative for improving visualization of the stomach. 相似文献
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Ioannis Tsitouridis PhD MD Charalampos Maskalidis MD Despoina Panagiotidou MD Eleni P Kariki MScHI MScHCM MD 《Journal of ultrasound in medicine》2014,33(10):1855-1864
We present the sonographic and magnetic resonance imaging findings of Leydig cell tumors in a series of patients, along with a brief review of the literature. We evaluated the sonographic features of 11 cases of Leydig cell tumors, including echogenicity, size, margins, and patterns of vascularity. The magnetic resonance imaging characteristics of 9 patients were also assessed, with special attention to the appearance of the tumors on T2-weighted imaging and postcontrast T1-weighted imaging. Seven tumors were hypoechoic, and 4 were almost isoechoic. Ten patients showed various patterns of hypervascularity in the tumors, combined in some cases with feeding vessels. One case presented with a single feeding vessel. The tumors showed homogeneous or heterogeneous low signal intensity on T2-weighted imaging and marked enhancement on postcontrast T1-weighted imaging. The small size of these tumors, the various patterns of vascularity on color and power Doppler sonography, and the marked enhancement on postcontrast T1-weighted imaging are considered valuable but generally nonspecific for identification of these tumors. 相似文献
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