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21.
A monokine regulates colony-stimulating activity production by vascular endothelial cells 总被引:20,自引:0,他引:20
Human umbilical vein endothelial cells were cultured in supernatants of peripheral blood monocytes that had been cultured for 3 days with and without lactoferrin. Colony-stimulating activity (CSA) was measured in supernatants of the endothelial cell cultures and appropriate control cultures using normal, T-lymphocyte-depleted, phagocyte-depleted, low- density bone marrow cells in colony growth (CFU-GM) assays. Monocyte- conditioned medium contained a nondialyzable, heat labile factor that enhanced 4-15--fold the production of CSA by endothelial cells. The addition of lactoferrin to monocyte cultures reduced the activity of this monokine by 69%. Lactoferrin did not inhibit CSA production by monokine-stimulated endothelial cells. Therefore, vascular endothelial cells are potent sources of CSA, the production of CSA by these cells is regulated by a stimulatory monokine, and the production and/or release of the monokine is inhibited by lactoferrin, a neutrophil- derived putative feedback inhibitor of granulopoiesis. Inasmuch as a similar monokine is known to stimulate CSA production by fibroblasts and T lymphocytes, we suggest that mononuclear phagocytes play a pivotal role in the regulation of granulopoiesis by recruiting a variety of cell types to produce CSA. 相似文献
22.
再发骨质疏松性椎体压缩骨折保守治疗患者出院后生存质量 总被引:1,自引:0,他引:1
目的:对比初次和再发骨质疏松性椎体压缩骨折(osteoporotic vertebral compression fractures,OVCFs)患者保
守治疗的生存质量,了解再次骨折对此类患者生存质量各方面的影响。方法:回顾性观察治疗OVCFs后出现再骨折
的患者30名(再骨折组)和同时期行保守治疗OVCFs后未发生再骨折的基本条件相似的患者30例(对照组),比较两组出
院后3个月时SF-36简明健康健康状况调查表的调查结果。结果:再骨折组治疗后的8个维度均不同程度较对照组变差
(均P<0.01)。结论:再骨折组患者的生存质量明显低于对照组,并且会进一步影响患者的心理预期、情绪和社会活动
的各个方面。 相似文献
23.
We analyzed three functional 5′ un-translated region β-defensin 1 (DEFB1) single nucleotide polymorphism (SNPs) in a group of 170 type 1 diabetes (T1D) patients. In order to evaluate the SNPs influence on the disease onset and the development of other autoimmune disorder, such as celiac disease (CD) and autoimmune thyroid disease (AITD), patients were stratified according to the presence of AITD, CD, and both AITD and CD. As control group, we studied 191 healthy children and adolescent not presenting a familiar historic of T1D, CD or AITD. DEFB1 SNPs were in Hardy–Weinberg equilibrium both in healthy controls and T1D patients, as well in the T1D patients stratified according to the presence of other autoimmune disorder(s). Allele, genotype, and haplotype frequencies of T1D patients globally considered were comparable to healthy controls ones. No evidence of any association of DEFB1 SNPs with the onset of AIDT, CD, and both AITD and CD on T1D patients was evidenced. Only a minor trend was found for an increased frequency of the ? 20 G allele in T1D patients only presenting AITD vs. T1D patients not presenting AITD or CD, as well as an increase of those haplotypes comprising the ? 20 G allele when compared with the GCA haplotype. We also evaluated the influence of functional DEFB1 SNPs on the age of T1D onset: no significant statistical conclusion was achieved. Further studies are envisaged, in order to elucidate the possible role of functional DEFB1 polymorphisms in the onset of TD1 and other autoimmune-related disorders. 相似文献
24.
KA Hodgkinson SP Connors N Merner A Haywood T‐L Young WJ McKenna B Gallagher F Curtis AS Bassett PS Parfrey 《Clinical genetics》2013,83(4):321-331
To determine the phenotype and natural history of a founder genetic subtype of autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVC) caused by a p.S358L mutation in TMEM43. The age of onset of cardiac symptoms, clinical events and test abnormalities were studied in 412 subjects (258 affected and 154 unaffected), all of which occurred in affected males significantly earlier and more often than unaffected males. Affected males were hospitalized four times more often than affected females (p ≤ 0.0001) and died younger (p ≤ 0.001). The temporal sequence from symptoms onset to death was prolonged in affected females by 1–2 decades. The most prevalent electrocardiogram (ECG) manifestation was poor R wave progression (PRWP), with affected males twice as likely to develop PRWP as affected females (p ≤ 0.05). Left ventricular enlargement (LVE) occurred in 43% of affected subjects, with 11% fulfilling criteria for dilated cardiomyopathy. Ventricular ectopy on Holter monitor was common and occurred early: the most diagnostically useful clinical test. No symptom or test could rule out diagnosis. This ARVC subtype is a sex‐influenced lethal arrhythmogenic cardiomyopathy, with a unique ECG finding, LV dilatation, heart failure and early death, where molecular pre‐symptomatic diagnosis has the greatest clinical utility. 相似文献
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29.
Molecular characterization of human factor XSan Antonio 总被引:1,自引:0,他引:1
Enzymatic amplification technique was used to isolate all eight exons and sequences around the splice junctions, putative promoter, and polyadenylation sites of human factor X DNA from a patient with factor X deficiency. Two genetic changes in factor X have been observed in this patient. The patient is most likely a compound heterozygote since there is only 14% activity associated with factor X. A point mutation that resulted in the substitution of cysteine (TGC) for arginine (CGC) at amino acid 366 was found in exon VIII of one allele of the factor X gene. This mutation, which occurs in the catalytic domain, can affect the formation of a disulfide bridge and thus could result in a reduction in factor X activity. Sequencing all the regions revealed a second mutation: a deletion of one nucleotide (TCCT to TCT) in exon VII that would cause a frame shift at amino acid 272 followed by termination. We have also shown that the point mutation in exon VIII creates an ApaL1 restriction site and destroys the HinP1 site. Enzymatic DNA amplification followed by restriction digestion provides a quick, reliable, and sensitive method for carrier detection and antenatal diagnosis in affected kindreds. This is the first characterization of factor X deficiency at the molecular level. We propose to name this mutation Factor XSan Antonio. 相似文献
30.
Activation of the coagulation cascade after infusion of a factor XI concentrate in congenitally deficient patients 总被引:5,自引:1,他引:5
Mannucci PM; Bauer KA; Santagostino E; Faioni E; Barzegar S; Coppola R; Rosenberg RD 《Blood》1994,84(4):1314-1319
Virally inactivated, high-purity factor XI concentrates are available for treatment of patients with factor XI deficiency. However, preliminary experience indicates that some preparations may be thrombogenic. We evaluated whether a highly purified concentrate produced signs of activation of the coagulation cascade in two patients with severe factor XI deficiency infused before and after surgery. Signs of heightened enzymatic activity of the common pathway of coagulation (elevated plasma levels of prothrombin fragment 1 + 2 and fibrinopeptide A) developed in the early post-infusion period, accompanied by more delayed signs of fibrin formation with secondary hyperfibrinolysis (elevated D-dimer and plasmin-antiplasmin complex). These changes occurred in both patients, but were more severe in the older patient with breast cancer when she underwent surgery, being accompanied by fibrinogen and platelet consumption. There were no concomitant signs of heightened activity of the factor VII-tissue factor mechanism on the factor Xase complex (plasma levels of activated factor VII and of factor IX and X activation peptides did not increase). The observed changes in biochemical markers of coagulation activation indicate that concentrate infusions increased thrombin generation and activity and that such changes were magnified by malignancy and surgery. Because some factor XI concentrates may be thrombogenic, they should be used with caution, especially in patients with other risk factors for thrombosis. 相似文献