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Severe Glanzmann's thrombasthenia is relatively frequent in Iraqi-Jews and Arabs residing in Israel. We have recently described the mutations responsible for the disease in Iraqi-Jews--an 11 base pair deletion in exon 12 of the glycoprotein IIIa gene, and in Arabs--a 13 base pair deletion at the AG acceptor splice site of exon 4 on the glycoprotein IIb gene. In this communication we show that the Iraqi-Jewish mutation can be identified directly by polymerase chain reaction and gel electrophoresis. With specially designed oligonucleotide primers encompassing the mutation site, an 80 base pair segment amplified in healthy controls was clearly distinguished from the 69 base pair segment produced in patients. Patients from 11 unrelated Iraqi-Jewish families had the same mutation. The Arab mutation was identified by first amplifying a DNA segment consisting of 312 base pairs in controls and of 299 base pairs in patients, and then digestion by a restriction enzyme Stu-1, which recognizes a site that is absent in the mutant gene. In controls the 312 bp segment was digested into 235 and 77 bp fragments, while in patients there was no change in the size of the amplified 299 bp segment. The mutation was found in patients from 3 out of 5 unrelated Arab families. Both Iraqi-Jewish and Arab mutations were detectable in DNA extracted from blood and urine samples. The described simple methods of identifying the mutations should be useful for detection of the numerous potential carriers among the affected kindreds and for prenatal diagnosis using DNA extracted from chorionic villi samples. 相似文献
3.
S Rozenberg J Vandromme A Peretz J P Praet C Robyn H Ham 《Journal of endocrinological investigation》1992,15(11):835-837
Examining the bone mineral density (BMD's) slope of patients regularly followed in our department, we observed recently that the group of patients who had their last BMD during the last 6 months of 1989, had a different slope than patients who had their last BMD during the following 6 months. In order to investigate if a small time-related bias of measurement, unsuspected by the former quality control investigations, could exist, we performed the following analyses. A regression equation between BMD and time was calculated and a slope was obtained for 95 women who had been followed for at least 3 yr and had had at least 3 BMD measurements during that time. The women were divided in 3 groups according to when the last BMD measurement had been performed (July-December 1989, January-June 1990 or July-December 1990). The slopes of the 3 groups of patients were compared. For each value of BMD of every patient, a predicted BMD (BMDp) was calculated using the regression equation and the relative difference (RD) between BMDp and BMD was calculated and analysed in relation to time. There was a significant difference (p < 0.05) between the slopes of patients in relation to the time when the last BMD had been measured. Significant fluctuations (p < 0.001) in RD were observed in relation to time. These RD variations suggested the existence of a time-related error. The presence of this error is also substantiated by the fact that a parallelism existed between the curve of the RD variations and the curve of the mean values of BMD of all patients referred to our department, calculated per period of 4 months. Although the fluctuation of the latter curve was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
How to perform electrogram-guided atrial fibrillation ablation. 总被引:14,自引:0,他引:14
5.
Freezing of gait affects quality of life of peoples with Parkinson's disease beyond its relationships with mobility and gait. 总被引:1,自引:0,他引:1
The aim of this study was to examine the association between freezing of gait (FOG) and quality of life (QoL) in patients with Parkinson's disease (PD). PD patients (n = 118) completed the PDQ-39 (QoL) and FOG-Q questionnaires. Disease severity was assessed by the Hoehn and Yahr (H&Y) staging and the Unified Parkinson's Disease Rating Scale (UPDRS). The relations between those parameters were assessed using regression models. 66 men and 52 women (mean age 65.8 +/- 10.2 years, UPDRS total score 48.4 +/- 17.1, disease duration 8.5 +/- 5.8 years, H&Y stage 2.7 +/- 0.8) participated. FOG severity had a significant effect on QoL (P < 0.0015), accounting for disease severity assessed by UPDRS. Specifically, FOG severity was correlated with all the dimensions of the PDQ-39 except for stigma and social support, as follows: with mobility, bodily discomfort, activity of daily living (ADL) (P < 0.005 in all), with emotional, communication, and cognition (P < 0.05 in all). FOG severity (FOG-Q) was also found to affect a modified PDQ total score, without the mobility aspect (P = 0.0081). FOG should be viewed as a highly important symptom with regard to QoL of PD patients beyond its effect on gait and mobility. On the basis of the present results, special attention should be given to FOG in the treatment of patients with PD. 相似文献
6.
Allicin inhibits SDF-1alpha-induced T cell interactions with fibronectin and endothelial cells by down-regulating cytoskeleton rearrangement, Pyk-2 phosphorylation and VLA-4 expression 总被引:2,自引:0,他引:2
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Sela U Ganor S Hecht I Brill A Miron T Rabinkov A Wilchek M Mirelman D Lider O Hershkoviz R 《Immunology》2004,111(4):391-399
Allicin, a major ingredient of fresh garlic extract that is produced during the crushing of garlic cloves, exerts various beneficial biological effects, including a broad spectrum of antimicrobial activity, antihyperlipidaemic and antihypertensive effects. However, how allicin affects the immune system is less well known, and its effect on human T cells has never been studied. Here, we examined the in-vitro effects of allicin on the functioning of T cells related to their entry to inflamed extravascular sites. We found that allicin (20-100 microm) inhibits the SDF-1alpha (CXCL12)-induced T cell migration through fibronectin (FN), and that this inhibition is mediated by the down-regulation of (i) the reorganization of cortical actin and the subsequent T cell polarization, and (ii) T cell adhesion to FN. Moreover, allicin also inhibited T cell adhesion to endothelial cells and transendothelial migration. The mechanisms underlying these inhibitory effects of allicin are associated with its ability to down-regulate the phosphorylation of Pyk2, an intracellular member of the focal adhesion kinases, and to reduce the expression of the VCAM-1- and FN-specific alpha4beta1-integrin (VLA-4). The ability of allicin to down-regulate these chemokine-induced and VLA-4-mediated T cell functions explains its beneficial biological effects in processes where T cells play an important role and suggests that allicin may be used therapeutically with chronic inflammatory diseases. 相似文献
7.
Ayelet Gonen Dror Harats Aharon Rabinkov Talia Miron David Mirelman Meir Wilchek Lev Weiner Esfir Ulman Hana Levkovitz Dikla Ben-Shushan Aviv Shaish 《Pathobiology》2005,72(6):325-334
OBJECTIVE: Garlic (Allium sativum) has been suggested to affect several cardiovascular risk factors. Its antiatherosclerotic properties are mainly attributed to allicin that is produced upon crushing of the garlic clove. Most previous studies used various garlic preparations in which allicin levels were not well defined. In the present study, we evaluated the effects of pure allicin on atherogenesis in experimental mouse models. METHODS AND RESULTS: Daily dietary supplement of allicin, 9 mg/kg body weight, reduced the atherosclerotic plaque area by 68.9 and 56.8% in apolipoprotein E-deficient and low-density lipoprotein (LDL) receptor knockout mice, respectively, as compared with control mice. LDL isolated from allicin-treated groups was more resistant to CuSO(4)-induced oxidation ex vivo than LDL isolated from control mice. Incubation of mouse plasma with (3)H-labeled allicin showed binding of allicin to lipoproteins. By using electron spin resonance, we demonstrated reduced Cu(2+) binding to LDL following allicin treatment. LDL treatment with allicin significantly inhibited both native LDL and oxidized LDL degradation by isolated mouse macrophages. CONCLUSIONS: By using a pure allicin preparation, we were able to show that allicin may affect atherosclerosis not only by acting as an antioxidant, but also by other mechanisms, such as lipoprotein modification and inhibition of LDL uptake and degradation by macrophages. 相似文献
8.
Allicin stimulates lymphocytes and elicits an antitumor effect: a possible role of p21ras 总被引:7,自引:0,他引:7
Patya M Zahalka MA Vanichkin A Rabinkov A Miron T Mirelman D Wilchek M Lander HM Novogrodsky A 《International immunology》2004,16(2):275-281
Allicin, the main organic allyl sulfur component in garlic, exhibits immune-stimulatory and antitumor properties. Allicin stimulated [(3)H]thymidine incorporation in mouse splenocytes and enhanced cell-mediated cytotoxicity in human peripheral mononuclear cells. Multiple administration (i.p.) of allicin elicited a marked antitumor effect in mice inoculated with B-16 melanoma and MCA-105 fibrosarcoma. The immune-stimulatory and antitumor effects of allicin are characterized by a bell-shaped curve, i.e. allicin at high, supra-optimal concentrations is less effective or inhibitory. Allicin induced activation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) in human peripheral mononuclear cells, and also in wild-type Jurkat T-cells. Allicin failed to activate ERK1/2 in Jurkat T cells that express p21(ras), in which Cys118 was replaced by Ser. These cells are not susceptible to redox-stress modification and activation. We postulate that the immune stimulatory effect of allicin is mediated by redox-sensitive signaling such as activation of p21(ras). It is suggested that the antitumor effect of allicin is related to its immune-stimulatory properties. 相似文献
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10.
Kessel A Rosner I Rozenbaum M Zisman D Sagiv A Shmuel Z Sabo E Toubi E 《Journal of clinical immunology》2004,24(1):30-36
Our objectives were (1) to compare lymphocyte subpopulation apoptosis rates in SSc patients versus healthy controls and (2) to compare Bcl-2 and NF-kappa B expression in cultured CD8 lymphocytes of SSc patients versus controls. Peripheral blood samples were obtained from 27 SSc patients meeting the American College of Rheumatology criteria for SSc and 28 healthy individuals. Mononuclear cells were isolated by Ficoll-Hypaque density gradient separation and cultured for 48 hr. For determination of apoptosis within specific cell populations, samples were labeled with PE-conjugated monoclonal antibody to CD8, CD4, and a FITC-conjugated monoclonal antibody to Annexin V. Flow cytometry was carried out with a FACS operating with Cellquest software. CD8+ lymphocytes were positively selected with magnetic microbeads conjugated to antihuman CD8. CD8 T cells were separated, then incubated with activation for 48 hr, and NF-kappa B and Bcl-2 analysis was carried out using Western immunoblotting. The CD4:CD8 ratio was increased in SSc compared to controls (2.6 +/- 1.13 vs.1.87 +/- 0.76; P = 0.018). The spontaneous apoptosis rate of SSc CD8 lymphocytes was increased compared to that of controls of (21.9 +/- 13.7 vs. 13.3 +/- 9.9; P = 0.019). No difference was found in the rate of CD4 apoptosis of SSc patients versus controls (9.8 +/- 5.2 vs. 7.18 +/- 4.89%; P = ns). The expression of NF-kappa B in SSc CD8 lymphocytes was decreased compared with that of CD8 lymphocytes from healthy controls (144 +/- 13 vs. 188 +/- 11; P = 0.018). Whereas expression of Bcl-2 was similar in activated CD8+ T cells of SSc patients and healthy controls, CD8+ T cell apoptosis rate was found to be in reverse correlation with expression of NF-kappa B in these cells ( r = - 0.53, P = 0.029). The increased CD4:CD8 ratio in SSC may result from increased CD8+ T cell apoptosis. Increased SSc CD8 T cell apoptosis is associated with low levels of NF-kappa B. 相似文献