Human vascular adhesion protein-1 in smooth muscle cells

Human vascular adhesion protein-1 (VAP-1) is a dual-function molecule with adhesive and enzymatic properties. In addition to synthesis in endothelial cells, where it mediates lymphocyte binding, VAP-1 is expressed in smooth muscle cells. Here we studied the expression, biochemical structure, and function of VAP-1 in muscle cells and compared it to those in endothelial cells. VAP-1 is expressed on the plasma membrane of all types of smooth muscle cells, but it is completely absent from cardiac and skeletal muscle cells. In tumors, VAP-1 is retained on all leiomyoma cells, whereas it is lost in half of leiomyosarcoma samples. In smooth muscle VAP-1 predominantly exists as a approximately 165-kd homodimeric glycoprotein, but a trimeric (approximately 250 kd) form of VAP-1 is also found. It contains N-linked oligosaccharide side chains and abundant sialic acid decorations. In comparison, in endothelial cells dimeric VAP-1 is larger, no trimeric forms are found, and VAP-1 does not have N-glycanase-sensitive oligosaccharides. Unlike endothelial VAP-1, VAP-1 localized on smooth muscle cells does not support binding of lymphocytes. Instead, it deaminates exogenous and endogenous primary amines. In conclusion, VAP-1 in smooth muscle cells is structurally and functionally distinct from VAP-1 present on endothelial cells.     

Induced abortion is not a cause of subsequent preterm delivery in teenage pregnancies

To examine the possible impact of previous induced abortion on the occurrence of preterm delivery in the subsequent pregnancy in teenage women, a retrospective case-control study was performed on mothers aged 13-19 years who delivered in one tertiary hospital over a 4 year period. Those who had a history of induced abortion prior to the index pregnancy were identified from the records and compared with a control group without previous induced abortion and who were matched for maternal age and parity. Of the 118 cases thus identified, 28 (23.7%) had more than one induced abortions and 18 (15.3%) had one or more induced abortions in the second trimester. There were 10 (8.5%) para 1 cases. No significant differences could be demonstrated between the study and control groups in the maternal demographics, major pregnancy complications, or perinatal outcome, except for the incidence of smokers which was significantly higher (39.0 versus 14.4%, P < 0.02) in the study group. The number of previous induced abortions did not appear to be related to the incidence of preterm labour, which was 10.2 and 8.5% in the study and control groups respectively. Our findings indicate that previous induced abortion is not a significant cause of preterm labour and delivery in teenage pregnancies.      

Prognostic factors for an unsatisfactory primary methotrexate treatment of cervical pregnancy: a quantitative review

To determine the risks when the primary methotrexate (MTX) treatment of cervical pregnancy has an unsatisfactory outcome, we conducted a Medline search on relevant literature published from January 1983 to June 1997. The search yielded 28 publications of 48 cases of cervical pregnancy. These and four new cases from our institutions were used in our study. A cervical pregnancy that presented with a serum beta-human chorionic gonadotrophin concentration of > or = 10,000 mIU/ml [odds ratio (OR) 10.82, 95% confidence interval (CI) 2.59, 45.14], gestational age at > or = 9 weeks (OR 6.44, 95% CI 1.46, 28.52), embryonic cardiac activity (OR 14.29, 95% CI 2.95, 76.92), and crown- rump length of >10 mm (OR 13.33, 95% CI 1.46, 120.48) was considered to be associated with a higher unsatisfactory rate of primary MTX treatment. A concomitant feticide was found to enhance the therapeutic effect of MTX treatment if embryonic cardiac activity was evident (OR 0.13, 95% CI 0.02, 0.68). Administration of a high dose of MTX did not seem to be more effective than a lower one. Our findings supported some previous observations and, more importantly, provided useful clinical information in selecting appropriate candidates for MTX treatment in cases of cervical pregnancy.      

Endothelium dependence of prostanoid-induced relaxation in human hand veins

The endothelium dependence of prostanoid-induced relaxation was examined in human isolated hand veins precontracted by endothelin. Indomethacin (10^-6 mol l^-1) and the thromboxane A₂-receptor antagonist BM 13.505 (10^-6 mol l^-1) were present throughout. The endothelium was removed by insufflating carbogen through the vessel lumen. Prostaglandin (PG) F_2α, PGE₁ PGE₂, and prostacyclin (PGI₂) elicited concentration-dependent relaxant effects. Removal of the endothelium reduced the relaxation induced by PGE_2α and PGE₂, but not that elicited by PGE₁ and PGI₂. The order of potency was PGE₂? PGE₁? PGI₂? PGF_2α regardless of the presence or absence of endothelium. The relaxation elicited by an acidified solution of NaNO₂ (generating nitric oxide) was almost identical in intact and endothelium-denuded vein segments. The results are compatible with the existence of two prostanoid receptor populations mediating relaxation: (1) one located on the smooth muscle cells and; (2) another present on the endothelium or possibly on the smooth muscle and modulated by the endothelium. The latter receptor appears to be activated by PGF_2α and PGE₂, but not by PGE₁ and PGI₂.     

Hyperglycemic glucose concentrations up-regulate the expression of type VI collagen in vitro. Relevance to alterations of peripheral nerves in diabetes mellitus.

Electron microscopy of peripheral nerves obtained from two diabetic patients revealed large deposits of microfibrils and the presence of Luse bodies in the vicinity of perineurial cells. Microfibrils were found to accumulate also in the sciatic nerves of diabetic BB rats; these microfibrillar deposits were shown to contain type VI collagen by immunoelectron microscopy. Connective tissue cells cultured from rat sciatic nerves were exposed to high glucose concentrations. High glucose concentrations up-regulated the mRNA steady-state levels of alpha 1(VI), alpha 2(VI), and alpha 3(VI) chains of type VI collagen and caused accumulation of type VI collagen-containing fibrils in the cultures. Immunostaining and in situ hybridizations demonstrated that perineurial cells, Schwann cells, and fibroblasts expressed type VI collagen at the mRNA and protein levels. The results suggest that the turnover and supramolecular assembly of type VI collagen are perturbed in diabetic nerves and that glucose per se increases the expression of type VI collagen in vitro.     

Stimulation of megakaryocytopoiesis by acute thrombocytopenia in rats

Rats were made acutely thrombocytopenic by injection of antiplatelet serum. Marrow sections and squash preparations were made at intervals during 120 hr. Determinations were made of mitotic index, stage of maturation, ploidy level, and cell size of megakaryocytes; number and size of platelets were measured. Increased endomitosis among megakaryocytes was followed by an increase in the proportion of immature megakaryocytes, a greater average ploidy level of recognized megakaryocytes, and larger megakaryocytes. Maximum changes in these several parameters occurred between 32 and 72 hr after induction of thrombocytopenia. By 120 hr all megakarocyte parameters were near normal. For about 3 days, beginning at about 36 hr, platelet numbers increased rapidly. Average platelet size rose and returned to normal within about 60 hr. Changes in ploidy and size of megakaryocytes were measured in the immature and mature maturation stages. The results suggest that the initial stimulus in response to acute thrombocytopenia acts primarily on diploid precursors, programming them to mature into a population of megakaryocytes with an average ploidy approximately one level greater than in normal rats and a proportionate increase in cell size. The larger megakaryocytes presumably produce more platelets, accounting for a major part of the increased rate of platelet production. Since the changes in megakaryocytes begin to reverse before circulating platelet numbers have reached the normal level, reversal of the stimulus appears to be initiated by some change other than platelet mass.     

Immunoreactive interleukin-6 and acute phase proteins as prognostic factors in multiple myeloma. Finnish Leukemia Group

High serum level of bioactive interleukin-6 (IL-6) is regarded as a predictor of poor prognosis in multiple myeloma (MM). On the other hand, the reported levels of immunoreactive IL-6 have been highly variable, and the prognostic value of immunoreactive IL-6 in MM is not clear. We have analyzed the prognostic significance of serum immunoreactive IL-6, as measured by a sensitive immunosorbent assay, in 210 patients with newly diagnosed MM subsequently treated with intermittent melphalan and prednisone. The serum levels of acute phase proteins C-reactive protein (CRP), alpha 1-antitrypsin (alpha 1AT), and acid alpha 1-glycoprotein (orosomucoid; OM) were evaluated as surrogates for IL-6. Serum IL-6, CRP, alpha 1AT, and OM levels were raised in 42%, 40%, 41%, and 24% of the patients, respectively. There was a significant correlation between the clinical stage of the patients and serum IL-6 (P = .006), alpha 1AT (P = .001), and OM (P = .004) levels at diagnosis. At 3 years, 52% of the patients were alive. Univariate logistic regression analysis showed that high levels of IL-6 (P = .002), CRP (P = .02), alpha 1AT (P < .001), OM (P = .007), beta 2- microglobulin (beta 2M; P < .001), and thymidine kinase (P < .05) were all associated with 3-year mortality. In multivariate regression analysis, beta 2M (P < .0001) and alpha 1AT (P = .01) had independent prognostic significance. The patients with high levels of both beta 2M and alpha 1AT or IL-6 were at very high risk of dying within 3 years from diagnosis (16% and 21% of the patients in these groups were alive, respectively). When the patients were stratified according to the clinical stage, the prognostic significance of serum IL-6 and alpha 1AT was especially evident in stage II patients. When the patients were divided into two groups according to normal or raised serum IL-6 levels, the patients with high IL-6 levels had more frequent osteolytic bone lesions (P = .03) and a more aggressive disease. We conclude that serum immunoreactive IL-6 is a significant prognostic marker in MM.     

脐血间充质干细胞体外培养方法的改良及其成骨分化能力

目的:采用两种改良方法体外分离培养脐血间充质干细胞,并观察其成骨分化能力。方法:实验于2006-05/09在上海交通大学医学院附属第九人民医院骨与关节中心细胞实验室完成。①所用28份脐血标本由复旦大学医学院附属妇产科医院提供,取自足月健康顺产新生儿,产妇和家属均书面同意,实验经医学伦理委员会批准。②采集28份脐血标本,50～90mL/份,枸橼酸抗凝。采集后12h内密度梯度离心法分离出单个核细胞,接种于100mm×20mm培养皿中,细胞浓度为1×1010L-1,置于含体积分数为0.1胎牛血清的α-MEM培养液中原代培养,5～7d后半量换液,后每隔3～4d全量换液一次。③细胞贴壁后,分两组予以改良培养。改良1组10份,当培养皿底圆形巨核细胞融合、梭形成纤维样细胞脱落时将细胞悬液移入新的培养皿中培养;改良2组18份,待培养皿底圆形巨核细胞渐渐占据优势时,将培养基更换为含体积分数为0.15小牛血清的α-MEM,当圆形巨核细胞大部脱落后换回含体积分数为0.1胎牛血清的α-MEM培养基。成纤维样细胞融合至80%～90%时胰酶消化,按1∶2或1∶3传代培养。④显微镜下观察脐血间充质干细胞的形态。取第5代脐血间充质干细胞,采用流式细胞仪测定细胞免疫表型,以碱性磷酸酶法检测成骨分化能力。结果:①28份脐血间充质干细胞中,共20份原代培养中出现贴壁细胞(改良1组6份,改良2组14份),其中13份培养出能融合且可稳定传代的成纤维样细胞(改良1组4份,改良2组9份),成功率46.4%。②原代培养5～7d后贴壁细胞呈梭形成纤维样细胞和圆形巨核细胞。改良1组与2组于原代培养5周可见成纤维样细胞集落,细胞形态与骨髓间充质干细胞相似,呈较均一的长梭形,传至22代形态无明显变化。③可强烈表达CD29、CD105等间充质干细胞表面标志,而不表达CD34、CD45和CD106等造血干细胞和内皮细胞标志。④成骨诱导1周,脐血间充质干细胞可分化为成骨细胞,碱性磷酸酶染色呈阳性。结论:脐血中存在的单个核细胞经过改良培养后,可提高脐血间充质干细胞的培养成功率。脐血间充质干细胞具有与其他来源的单个核细胞类似的表型及成骨分化潜能,且易于体外扩增、传代稳定。     

注射用右兰索拉唑治疗急性胃和/或十二指肠溃疡引起的上消化道出血的有效性及安全性

目的：以注射用兰索拉唑为对照,评价注射用右兰索拉唑15 mg q12 h治疗急性胃和/或十二指肠溃疡引起的上消化道出血的有效性及安全性。方法：选取全国31家研究中心的急性胃和/或十二指肠溃疡引起的上消化道出血患者共202例,按照1∶1随机分配至试验组（注射用右兰索拉唑组）和对照组（注射用兰索拉唑组）。主要疗效终点为72 h有效止血率。对主要疗效终点采用非劣效评价,非劣效性界值δ是10%。结果：有效性方面,全分析数据集分析结果显示：用药72 h后,注射用右兰索拉唑组有效止血率为96.08%(98/102);注射用兰索拉唑组有效止血率为98.00%(98/100),两组率差为-1.92%(95%CI-6.58,2.74)。两组72 h有效止血率差异无统计学意义（P=0.682 9）。两组率差的双侧界值均低于δ(10%),注射用右兰索拉唑非劣于注射用兰索拉唑。安全性方面,试验组的不良事件及不良反应发生率与对照组差异无统计学意义,无非预期不良反应和严重不良反应。主要的不良反应为白细胞计数降低、中性粒细胞计数降低等。结论：注射用右兰索拉唑15 mg q12 h在治疗急性胃和/或十二指肠溃疡引起的...