RGD肽类似物RGDPe抑制血小板活性的体外实验

目的为寻找活性高的肽类血小板聚集抑制剂，我们合成了ＲＧＤ（Ａｒｇ－Ｇｌｙ－Ａｓｐ）肽类似物－ＲＧＤＰｅ（Ａｃ－Ａｒｇ－Ｇｌｙ－Ａｓｐ－ＮＨＣＨ２ＣＨ２Ｃ６Ｈ５），以验证其体外抗血小板聚集活性。方法以人血为标本，采用比浊法测定血小板聚集和同位素标记方法测定其竞争性抑制１２５Ｉ标记的纤维蛋白原（Ｆｇｎ）与血小板糖蛋白（ＧＰ）Ⅱｂ／Ⅲａ结合的能力，并与Ｓｉｇｍａ公司合成的ＲＧＤＳ（阳性对照）和生理盐水（阴性对照）比较。结果ＲＧＤＰｅ抑制１２５Ｉ－Ｆｇｎ与活化血小板ＧＰⅡｂ／Ⅲａ结合的ＩＣ５０＝３．６４±０．５５×１０－５Ｍ（ＲＧＤＳ：６．０３±１．２４×１０－５Ｍ），抗ＡＤＰ诱导的血小板聚集ＩＣ５０＝７６．４２±５５．４２μＭ（ＲＧＤＳ：１１４．６７±４０．５５μＭ）。结论ＲＧＤＰｅ有较强的抑制血小板聚集活性，可能在体内有预防血栓形成功效。     

Cystatin-C and inflammatory markers in the ambulatory elderly

Purpose

Inflammatory factors are elevated in persons with severe renal dysfunction, but their association across all levels of renal function is unclear. We compared cystatin-C, a novel marker of renal function, with creatinine and estimated glomerular filtration rate (eGFR) as predictors of C-reactive protein and fibrinogen levels.

Methods

This study is a cross-sectional analysis to evaluate cystatin-C, creatinine, and eGFR as predictors of the inflammatory markers C-reactive protein and fibrinogen. Participants included 4637 ambulatory elderly patients from the Cardiovascular Health Study. Multivariate linear regression was used to determine the independent associations of each renal function measurement with the inflammatory marker outcomes.

Results

After adjustment for confounding factors, cystatin-C was correlated with both C-reactive protein (coefficient = 0.13; 95% confidence interval: 0.10-1.16, P <.0001) and fibrinogen levels (0.15; 0.13-0.18, P <.0001). Associations were larger than those for creatinine and C-reactive protein (0.05; 0.02-0.07, P = .003) or fibrinogen (0.07; 0.04-0.10, P <.0001). Adjusted levels of C-reactive protein increased incrementally across quintiles of cystatin-C, from a median of 2.2 mg/L in quintile 1 to 3.7 mg/L in quintile 5. In contrast, both C-reactive protein and fibrinogen had U-shaped associations with quintiles of creatinine and eGFR, because the inflammatory markers were equivalently elevated in quintiles 1 and 5.

Conclusions

The finding of a significant linear association of cystatin-C and inflammation markers suggests that even small reductions in renal function may be associated with adverse pathophysiologic consequences.     

氟化钠-壳聚糖凝胶对乳牙釉质早期龋再矿化实验观察

目的:探讨氟化钠壳聚糖凝胶促进乳牙釉质早期龋模型再矿化的可行性.方法:乳前牙试件使用乳酸羧甲基纤维素凝胶预处理,制备早期龋模型;早期龋的乳前牙试件随机分成4组(n=6),3组分别进行氟化钠壳聚糖凝胶、壳聚糖空白凝胶、多乐氟处理,1组作为空白对照,处理完成后进行pH循环,SEM、EDS检测循环完成后的试件表面.结果:SEM观察,氟化钠壳聚糖凝胶能更好的保护釉质表层结构不受破坏,而多乐氟和空白对照组,则表现出釉质表层的崩解.同时氟化钠壳聚糖凝胶有更多的矿化物结晶在釉质表面形成.EDS检测钙离子的沉积比例,氟化钠壳聚糖凝胶组明显多于其余各组(P＜0.05).结论:氟化钠壳聚糖凝胶可以提高乳前牙早期龋的再矿化水平.     

富血小板凝胶在糖尿病足溃疡治疗中的应用

富血小板凝胶是近年来新出现的辅助治疗糖尿病足溃疡(DFU)的方法之一.局部应用富血小板凝胶治疗DFU可有效改善DFU的难愈合性并提高溃疡愈合率,且无明显不良反应发生;也可降低截肢率,且没有增加医疗总费用.富血小板凝胶治疗DFU的作用机制可能与其中富含的生长因子、细胞因子和白细胞等有关,还可能与凝胶超微结构、溃疡中基质金属蛋白酶的变化有关.     

Clonal evolution multi-drug resistant Acinetobacter baumannii by pulsed-field gel electrophoresis

Background: Acinetobacter baumannii is usually multi-drug resistant (MDR), including third generation cephalosporins, amino glycosides and fluoroquinolone. Resistance to these antibiotics is mediated by multiple factors such as: lactamases, efflux pumps and other mechanisms of resistance. Pulsed-field gel electrophoresis (PFGE) was then used to investigate the genetic relationships among the MDR isolates. Aim: The aim of this study was to determine MDR isolates and the existence of OXAs genes among MDR isolates of A. baumannii collected from Kermanshah hospitals in west of Iran. Materials and Methods: Forty-two MDR A. baumannii were collected from patients at Kermanshah hospitals. The isolates were identified by biochemical tests and API 20NE kit. The susceptibility to different antibiotics by disk diffusion method was determined. Polymerase chain reaction (PCR) was performed for detection of bla_OXA-23-like, bla_OXA-24-like, bla_OXA-51-like and bla_OXA-58-like betalactamase genes in isolates and clonal relatedness was done by PFGE (with the restriction enzyme ApaI) and patterns analyzed by Bionumeric software. Results: This study showed high resistant to ciprofloxacin, piperacillin, ceftazidime and also resistant to other anti-microbial agents and more spread blaOXA-23-like gene (93%) in MDR isolate. The PFGE method obtained six clones: A (10), B (9), C (5), D (4), E (11) and F (3) that clone E was outbreak and dominant in different wards of hospitals studied. Conclusion: An isolate from the emergency ward of these hospitals had indistinguishable isolates PFGE profile and similar resistance profile to isolates from intensive care unit (ICU), suggesting likely transmission from ICU to emergency via patient or hospital staff contact.     

A proteomic analysis on human sperm tail: comparison between normozoospermia and asthenozoospermia

Purpose

Asthenozoospermia is a common cause of human male infertility characterized by reduced sperm motility. The molecular mechanism that impairs sperm motility is not fully understood. This study proposed to identify novel biomarkers by focusing on sperm tail proteomic analysis of asthenozoospermic patients.

Methods

Sperm were isolated from normozoospermic and asthenozoospermic semen samples. Tail fractions were obtained by sonication followed by Percoll gradient. The proteins were extracted by solubilization and subjected to two-dimensional gel electrophoresis (2-DE); then, the spots were analyzed using Image Master 2D Platinum software. The significantly increased/decreased amounts of proteins in the two groups were exploited by matrix-assisted laser desorption-ionization time-of-flight/time-of-flight (MALDI-TOF-TOF) mass spectrometry.

Results

Three hundred ninety protein spots were detected in both groups. Twenty-one protein spots that had significantly altered amounts (p < 0.05) were excised and exploited using MALDI-TOF-TOF mass spectrometry. They led to the identification of the following 14 unique proteins: Tubulin beta 2B; glutathione S-transferase Mu 3; keratin, type II cytoskeletal 1; outer dense fiber protein 2; voltage-dependent anion-selective channel protein 2; A-kinase anchor protein 4; cytochrome c oxidase subunit 6B; sperm protein associated with the nucleus on the X chromosome B; phospholipid hydroperoxide glutathione peroxidase-mitochondrial; isoaspartyl peptidase/L-asparaginase; heat shock-related 70 kDa protein 2; stress-70 protein, mitochondrial; glyceraldehyde-3-phosphate dehydrogenase, testis-specific and clusterin.

Conclusion

Fourteen proteins present in different amounts in asthenozoospermic sperm tail samples were identified, four of which are reported here for the first time. These proteins might be used as markers for the better diagnosis of sperm dysfunctions, targets for male contraceptive development, and to predict embryo quality.     

肝硬化患者凝血、抗凝及纤溶指标的变化与Child-Pugh分级的关系

目的 探讨肝硬化患者凝血、抗凝及纤溶指标的变化及其与Child-Pugh分级的关系。 方法肝硬化患者43例,Child-Pugh分级A级13例,B级15例,C级15例。正常对照组16例,男11例,女5例。均检测凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)、纤维蛋白原(Fib)、凝血因子Ⅱ、Ⅴ、Ⅶ、Ⅷ、Ⅸ、Ⅹ、血管性假性血友病因子(vWF)、抗凝血酶-Ⅲ(AT-Ⅲ)、蛋白-C(PC)、D-二聚体(D-d)、组织纤溶酶原激活物(t-PA)抗原和组织纤溶酶原激活物抑制剂(PAI)。 结果 PT、APTT随病情加重而显著延长,F值分别为32.828和18.743,P值均<0.01;Fib随病情加重逐渐降低,F=4.747,P<0.01。凝血因子Ⅱ、Ⅴ、Ⅶ、Ⅸ、Ⅹ随病情加重活性逐渐降低,F值分别为43.129、12.677、36.405、9.380和21.988,P值均<0.01。Ⅷ、vWF因子随病情加重活性逐渐增高,F值分别为16.672和14.657,P值均<0.01。AT-Ⅲ、PC随病情加重活性逐渐降低,F值分别为22.602和15.430,P值均<0.01。D-d、t-PA抗原随病情加重逐渐增高,F=5.957,P<0.05。PAI活性正常对照组和3组患者检测结果近似,差异无统计学意义。 结论 肝硬化患者存在明显的凝血、抗凝血以及纤溶机制的异常,且与肝硬化程度密切相关。在防治肝硬化患者出血时,不仅要纠正患者的凝血因子异常,还要给予一定的抗纤溶治疗。     

Effects of selenium deficiency on the rat myocardial protein pattern – investigation by two-dimensional gel electrophoresis

Dietary selenium deficiency represents an etiological factor in “Keshan disease”, a distinct form of an endemic cardiomyopathy. The biochemical effects of selenium depletion in the myocardium are, however, not yet known. Therefore, we investigated the changes in the myocardial protein pattern in rats after long-term selenium deficiency. The myocardial proteins were analyzed in samples from five selenium-depleted rats (Se-deficient group) and five rats supplied with adequate amounts of the element (Se-adequate group). Isoelectric focusing (IEF) with carrier ampholytes on large 2-DE gels was used for the separation of proteins in the first dimension and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for the second dimension. The protein patterns were evaluated by means of a computer-assisted gel analysis system. The biochemical identification of the proteins of interest was achieved by matrix-assisted laser desorption/ionization mass spectrometry (MALDI) or immunoblotting. On average, 588 ± 68 protein spots were found on the gels. No significant difference in spot numbers existed between the groups. A pattern of 270 spots with identical positions was found on every gel; 247 of these spots were not saturated and used for quantitative comparison. Thirty-five, i. e., 14%, differed significantly in their relative intensity in the two groups. Twenty-eight protein spots were decreased in the Se-deficient group and seven were increased. Sarcomeric creatine kinase M chain, α-myosin heavy chain (α-MHC) and myosin light chain 1 and 2 (MLC 1 and 2) were largely decreased in Se-deficiency. Three protein spots were increased by more than twofold or appeared only in the Se-deficient group. A mitochondrial creatine kinase was identified in this group. The results suggest that selenium deficiency affects myocardial energy metabolism and contractile proteins. These changes probably reflect non-specific alterations in heart failure. Received: 19 February 1997, Returned for 1. revision: 7 April 1997, 1. Revision received: 29 January 1999, Returned for 2. revision: 18 February 1999, 2. Revision received: 21 December 1999, Accepted: 6 January 2000     

纤维蛋白原α链剪切位点IVS2＋1G〉C突变导致的遗传性低纤维蛋白原血症

目的：探讨遗传性低纤维蛋白原（Fg）血症的分子发病机制。方法：检测凝血指标以明确诊断；用DNA直接测序法对患者Fg基因FGA、FGB和FGG的所有外显子及其侧翼序列进行测序以寻找基因突变，对有突变的序列反向测序证实；通过逆转录结合巢式PCR扩增的方法，检测患者外周血中的Fg异位转录产物；构建含有突变点的突变型FGA小基因（minigene）质粒和野生型FGA小基因质粒，将2种质粒分别转染人胚肾（HEK）293T细胞，抽提RNA．逆转录PCR（RT—PCR）后TA克隆测序。结果：先证者呈FGA基因剪切位点IVS2＋1G〉C杂合突变；对于该突变，逆转录结合巢式PCR的产物经克隆后测序只检测到正常转录本，而没有发现异常转录本：突变型FGA小基因质粒转染HEK293T细胞后．抽提RNA再经RT-PCR、TA克隆、测序，揭示剪接过程中发生了FGA基因2号内含子滞留，导致终止密码的提前出现．从而使异常转录的mRNA在体内很快被降解。结论：异位转录结合体外表达证明先证者FGA基因剪切位点IVS2＋1G〉C突变导致异常转录mRNA在体内很快被降解，是先证者低Fg血症的原因之一。     

An anthropomorphic multimodality (CT/MRI) head phantom prototype for end-to-end tests in ion radiotherapy

With the increasing complexity of external beam therapy “end-to-end” tests are intended to cover every step from therapy planning through to follow-up in order to fulfill the higher demands on quality assurance. As magnetic resonance imaging (MRI) has become an important part of the treatment process, established phantoms such as the Alderson head cannot fully be used for those tests and novel phantoms have to be developed. Here, we present a feasibility study of a customizable multimodality head phantom. It is initially intended for ion radiotherapy but may also be used in photon therapy.As basis for the anthropomorphic head shape we have used a set of patient computed tomography (CT) images. The phantom recipient consisting of epoxy resin was produced by using a 3D printer. It includes a nasal air cavity, a cranial bone surrogate (based on dipotassium phosphate), a brain surrogate (based on agarose gel), and a surrogate for cerebrospinal fluid (based on distilled water). Furthermore, a volume filled with normoxic dosimetric gel mimicked a tumor.The entire workflow of a proton therapy could be successfully applied to the phantom. CT measurements revealed CT numbers agreeing with reference values for all surrogates in the range from 2 HU to 978 HU (120 kV). MRI showed the desired contrasts between the different phantom materials especially in T2-weighted images (except for the bone surrogate). T2-weighted readout of the polymerization gel dosimeter allowed approximate range verification.