The relationships among monocyte subsets,miRNAs and inflammatory cytokines in patients with acute myocardial infarction

Background

Acute myocardial infarction (AMI) causes irreversible myocardial damage and release of inflammatory mediators, including cytokines, chemokines and miRNAs. We aimed to investigate changes in the levels of cytokines (IL-6, TNF-α and IL-10), miRNAs profiles (miR-146 and miR-155) and distribution of different monocyte subsets (CD14++CD16-, CD14++CD16+, CD14+CD16++) in the acute and post-healing phases of AMI.

Effect of voice therapy with or without transcutaneous electrical stimulation on recovery of injured macroscopically intact recurrent laryngeal nerve after thyroid surgery

European Archives of Oto-Rhino-Laryngology - Electrical stimulation-supported therapy is an often used modality. However, it still belongs to experimental methods in the human larynx. Data are...     

Key bioactive reaction products of the NO/H2S interaction are S/N-hybrid species,polysulfides, and nitroxyl

Experimental evidence suggests that nitric oxide (NO) and hydrogen sulfide (H₂S) signaling pathways are intimately intertwined, with mutual attenuation or potentiation of biological responses in the cardiovascular system and elsewhere. The chemical basis of this interaction is elusive. Moreover, polysulfides recently emerged as potential mediators of H₂S/sulfide signaling, but their biosynthesis and relationship to NO remain enigmatic. We sought to characterize the nature, chemical biology, and bioactivity of key reaction products formed in the NO/sulfide system. At physiological pH, we find that NO and sulfide form a network of cascading chemical reactions that generate radical intermediates as well as anionic and uncharged solutes, with accumulation of three major products: nitrosopersulfide (SSNO⁻), polysulfides, and dinitrososulfite [N-nitrosohydroxylamine-N-sulfonate (SULFI/NO)], each with a distinct chemical biology and in vitro and in vivo bioactivity. SSNO⁻ is resistant to thiols and cyanolysis, efficiently donates both sulfane sulfur and NO, and potently lowers blood pressure. Polysulfides are both intermediates and products of SSNO⁻ synthesis/decomposition, and they also decrease blood pressure and enhance arterial compliance. SULFI/NO is a weak combined NO/nitroxyl donor that releases mainly N₂O on decomposition; although it affects blood pressure only mildly, it markedly increases cardiac contractility, and formation of its precursor sulfite likely contributes to NO scavenging. Our results unveil an unexpectedly rich network of coupled chemical reactions between NO and H₂S/sulfide, suggesting that the bioactivity of either transmitter is governed by concomitant formation of polysulfides and anionic S/N-hybrid species. This conceptual framework would seem to offer ample opportunities for the modulation of fundamental biological processes governed by redox switching and sulfur trafficking.Nitrogen and sulfur are essential for all known forms of life on Earth. Our planet’s earliest atmosphere is likely to have contained only traces of O₂ but rather large amounts of hydrogen sulfide (H₂S) (1). Indeed, sulfide may have supported life long before the emergence of O₂ and NO (2, 3).^* This notion is consistent with a number of observations: H₂S is essential for efficient abiotic amino acid generation as evidenced by the recent reanalysis of samples of Stanley Miller’s original spark discharge experiments (4), sulfide is an efficient reductant in protometabolic reactions forming RNA, protein, and lipid precursors (5), and sulfide is both a bacterial and mitochondrial substrate (6), enabling even multicellular lifeforms to exist and reproduce under conditions of permanent anoxia (7). Thus, although eukaryotic cells may have originated from the symbiosis of sulfur-reducing and -oxidizing lifeforms within a self-contained sulfur redox metabolome (8), sulfide may have been essential even earlier by providing the basic building blocks of life.The chemical reactions of sulfur-centered nucleophiles with a range of nitrogen-containing species have been studied for different reasons and as independent processes for more than a century, and early reports indicated complex reaction mechanisms (9–13). The recent surge of interest in this chemistry in the biological community (13–15) was triggered by a growing appreciation that NO and sulfide exert similar and often interdependent biological actions within the cardiovascular system and elsewhere (NO/H₂S “cross-talk”) (16, 17), resulting in mutual attenuation or potentiation of their responses. This cross-talk is possibly mediated by chemical interactions (18–20), but much of the older chemical work seems to have been forgotten. Recently, low concentrations of sulfide were shown to quench NO-mediated vascular responses through formation of an uncharacterized “nitrosothiol” (RSNO) (18–20), assumed to be thionitrous acid (HSNO) (13–15).A recent report of the detection by MS of the highly unstable HSNO at physiological pH (21) has attracted considerable attention from the biological community, because it could be an intermediate in the reaction of sulfide with RSNOs (22) and a precursor for NO, nitrosonium (NO⁺) equivalents, and nitroxyl (HNO). However, a key aspect of HSNO’s properties that seems to have been overlooked in these discussions is its mobile hydrogen, allowing facile 1,3 hydrogen shift and formation of four isomers with the same chemical equation (13)—a feature described in the seminal studies by Goehring in the 1950s (23) and by Müller and Nonella later on (24, 25) that distinguishes HSNO from all other RSNOs (26). The same feature also contributes to the short half-life of the molecule at ambient temperatures, making it more probable that other yet unknown entities are involved as biological mediators of the NO/H₂S cross-talk. Chemical studies by Seel and Wagner (9, 10) showed that NO readily reacts with HS⁻ in basic aqueous solution or organic solvents under anoxic conditions to form the yellow nitrosopersulfide (SSNO⁻). Accumulation of this product was also observed after reaction of RSNOs with sulfide at pH 7.4 (26, 27); moreover, SSNO⁻-containing mixtures were found to release NO, activate soluble guanylyl cyclase (sGC) (26), and relax vascular tissue (28), although a contribution of other reaction products to these effects cannot be excluded. Meanwhile, other sulfane sulfur molecules, including persulfides (RSSH) and polysulfides (RSS_n⁻ and HS_n⁻), have come to the fore as potential mediators of sulfide’s biological effects (29–31), but little is known about their pathways of formation, prevalence in biological systems, and relationship with NO.In view of this confusion, we sought to carry out an integrative chemical/pharmacological investigation to study the chemical biology of the reaction of NO with sulfide more thoroughly and systematically identify potentially bioactive reaction products. We here report that the NO/H₂S interaction leads to formation of at least three product classes with distinct in vivo bioactivity profiles: nitrosopersulfide (SSNO⁻), polysulfides (HS_n⁻), and dinitrososulfite [ONN(OH)SO₃⁻ or N-nitrosohydroxylamine-N-sulfonate (SULFI/NO)]; all anions at physiological pH. Their formation is accompanied by both scavenging and release of NO and H₂S and formation of nitrous oxide (N₂O), nitroxyl (HNO), nitrite (NO₂⁻), nitrate (NO₃⁻), and various sulfoxy species. These results not only offer an intriguing explanation for the quenching and potentiating effects of sulfide on NO bioavailability but also, provide a novel framework for modulation of fundamental biological processes governed by redox switching and sulfur trafficking. This chemistry is likely to prevail wherever NO and sulfide are cogenerated.     

Protein crystal structure obtained at 2.9 ? resolution from injecting bacterial cells into an X-ray free-electron laser beam

It has long been known that toxins produced by Bacillus thuringiensis (Bt) are stored in the bacterial cells in crystalline form. Here we describe the structure determination of the Cry3A toxin found naturally crystallized within Bt cells. When whole Bt cells were streamed into an X-ray free-electron laser beam we found that scattering from other cell components did not obscure diffraction from the crystals. The resolution limits of the best diffraction images collected from cells were the same as from isolated crystals. The integrity of the cells at the moment of diffraction is unclear; however, given the short time (∼5 µs) between exiting the injector to intersecting with the X-ray beam, our result is a 2.9-Å-resolution structure of a crystalline protein as it exists in a living cell. The study suggests that authentic in vivo diffraction studies can produce atomic-level structural information.The advent of X-ray free-electron lasers (XFELs) has made it possible to obtain atomic resolution macromolecular structures from crystals with sizes approximating only 1/60th of the volume of a single red blood cell. Brief, intense pulses of coherent X-rays, focused on a spot of 3-μm diameter, have produced 1.9-Å-resolution diffraction data from a stream of lysozyme crystals, each crystal no bigger than 3 μm³ (1). A stream of crystals, not just one crystal, is required to collect the many tens of thousands of diffraction patterns that compose a complete data set. No single crystal can contribute more than one diffraction pattern because the XFEL beam is so intense and the crystals so small that the crystals are typically vaporized after a single pulse. Impressively, a photosystem I crystal no bigger than 10 unit cells (300 nm) on an edge produced observable subsidiary diffraction peaks between Bragg reflections, details which would be unobservable from conventionally sized crystals (2). With this new ability to collect diffraction patterns from crystals of unprecedentedly small dimensions, it is conceivable that high-resolution diffraction data could be collected from crystals in vivo. The structure obtained in this manner would be unaltered from that occurring naturally in a living cell, free from distortion that might otherwise potentially arise from nonphysiological conditions imposed by recrystallization. A practical advantage would also be gained by eliminating the need for a protein purification step, whether the in vivo grown crystals were naturally, or heterologously expressed (3).The nascent field of serial femtosecond crystallography (SFX) has published results on nine different macromolecular systems since its inception in 2009 (3, 9). The crystals for this study were not grown in artificial crystallization chambers as has been the protocol of conventional macromolecular crystallography since the 1950s. Instead, crystals were grown in cells. Specifically, they were grown in Sf9 insect cells, heterologously expressing Trypanosoma brucei cathepsin B. These in vivo-grown crystals were used for the XFEL diffraction experiment. To this end, the cells were lysed and the crystals were extracted before injecting them in the XFEL beam for data collection. This last purification step seems to be the only major departure from our goal of obtaining high-resolution structural information from crystal inclusions in vivo, without requiring the crystal to be extracted from the cell that assembled it. Here we attempt to go one step further than previous studies—to record diffraction from crystals within living cells.

Table 1.

SFX publications from XFEL sources to date

参三七皂苷Rg1预适应对5-氮胞苷诱导大鼠骨髓间充质干细胞向心肌细胞转化的干预

目的:用药物预适应方法进行干细胞诱导已有报道,本实验观察中药参三七皂苷Rg1对5-氮胞苷诱导大鼠骨髓间充质干细胞向心肌细胞转化中的作用。方法:实验于2003-01/05在南京医科大学药理教研室完成。①实验材料:清洁级SD大鼠8只。参三七皂苷Rg18mg,批号20021017,由云南省长春花生物制剂公司提供,加入不含胎牛血清的IMDM培养液10mL,调配成10-4mol/L溶液,4℃保存。5-氮胞苷(Sigma公司,批号021209)。②实验方法:贴壁法体外培养大鼠骨髓间充质干细胞。设立4组:空白对照组常规培养后进行无血清处理,每3d换液1次;5-氮胞苷单用组单纯以10μmol/L的5-氮胞苷进行处理,其终浓度为1×10-8moL/L,连续诱导15d;5-氮胞苷 参三七皂苷Rg1预适应组分别加入0.1,1μmol/L参三七皂苷Rg1培养液处理24h,再各以10μmol/L的5-氮胞苷进行诱导,其终浓度为1×10-8moL/L,连续诱导15d。③实验评估:取第2代骨髓间充质干细胞,绘制生长曲线并计算群体倍增时间。观察诱导后骨髓间充质干细胞的生长形态学特征和细胞超微结构变化。激光共聚焦显微镜测定细胞表面积变化和细胞内钙离子浓度。结果:①5-氮胞苷诱导后骨髓间充质干细胞的生长形态学特征和细胞超微结构变化:骨髓间质干细胞胞体逐渐增大并伸出细长突起,在突起末端出现分支,部分相邻细胞的突起连接成网,形态学上表现出向心肌细胞方向转化的特征。其超微结构呈梭形,有明显的肌丝,细胞核呈单椭圆形,位于细胞中央,间质干细胞形似心肌细胞。②参三七皂苷Rg1预适应对5-氮胞苷诱导的骨髓间充质干细胞增殖特性的影响:与5-氮胞苷单用组比较,5-氮胞苷 参三七皂苷Rg1预适应组从第3天开始细胞数明显增加,细胞生长曲线均无明显的生长平台期,达到高峰后细胞数开始减少。③参三七皂苷Rg1预适应对5-氮胞苷诱导的骨髓间充质干细胞表面积的影响:与空白对照组骨髓间充质干细胞表面积比较,5-氮胞苷单用组明显降低,0.1,1μmol/L参三七皂苷Rg1预适应则能显著升高5-氮胞苷诱导的骨髓间充质干细胞表面积(P<0.01)。④参三七皂苷Rg1对5-氮胞苷诱导的骨髓间充质干细胞内游离钙水平的影响:与空白对照组比较,5-氮胞苷诱导4周后骨髓间充质干细胞内游离Ca2 相对荧光强度均明显升高(t=6.72,P<0.01),且5-氮胞苷 1μmol/L参三七皂苷Rg1预适应组升高幅度大于5-氮胞苷单用组(t=3.13,P<0.05)。结论:①参三七皂苷Rg1预适应在体外可显著刺激5-氮胞苷诱导的鼠骨髓间充质干细胞向心肌细胞转化和增殖,改善细胞形态,刺激细胞内钙离子增加。②参三七皂苷Rg1与5-氮胞苷对骨髓间充质干细胞向心肌细胞定向分化产生协同效应。     

Effectiveness of a prospective physician self-audit transfusion- monitoring system

BACKGROUND: The purpose of this study was to search for a more effective transfusion-monitoring system than the existing system of retrospective peer review. STUDY DESIGN AND METHODS: This research used a study-control, preintervention and postintervention design, to evaluate the effectiveness of a prospective physician self-audit transfusion-monitoring system that functioned without the direct involvement of transfusion service physicians. This research also evaluated the effectiveness of issuing to physicians a memo with transfusion guidelines. Three process indicators were used to assess physician behavior at various stages of the blood-ordering process: 1) the number of crossmatches ordered per admission, 2) the transfusion-to- crossmatch ratio, and 3) the number of blood units returned to the laboratory after physician self-auditing. The study used two outcome indicators to reflect overall blood utilization: 1) the percentage of patients who received red cell transfusions and 2) the number of blood units transfused per recipient each month. RESULTS: The prospective physician self-audit system implemented at the study hospital did not reverse physician transfusion decisions, and the process of issuing to physicians a memo with transfusion guidelines at the control hospital failed to reduce blood usage. However, a transient reduction in blood utilization was observed at the study hospital. CONCLUSION: The reduction was hypothesized to be due to a Hawthorne effect, in which observed behavior is affected by the subject's awareness of the research study.     

O等位基因引起ABO基因型与表现型定型差异

保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液.     

自体干细胞移植治疗老年心肌梗死后心力衰竭

目的：实验以移植后3个月、6个月时间超声心动图客观指标评估了自体干细胞冠状动脉内移植治疗老龄心肌梗死后心力衰竭的效果和安全性。方法：选择2004—06／2006—06江苏省苏北人民医院心内科自愿接受干细胞移植的7例心肌梗死后心力衰竭患者，平均年龄69岁，心功能Ⅲ-Ⅳ级，左室射血分数〈50％。药物治疗基础上加用自体干细胞冠状动脉内移植治疗的方法，其中2例骨髓干细胞在体外扩增后获得，5例经粒细胞集落刺激因子皮下注射动员自体骨髓干细胞后分离外周血获得干细胞悬液。将采集的干细胞悬液经0ver-the-wire球囊导管中心腔注入梗死相关动脉。观察自体干细胞动员，培养，采集和回输过程中的不良反应。在移植前、移植后3月、6月应用超声心动图评价左室形态和心功能变化，室壁运动积分指数及6min步行距离。结果：7例患者均进入结果分析。移植3个月后，心功能得到改善，超声心动图检查左室收缩期内径及射血分数变化不大，6min步行距离有所提高，但差异无显著性（P〉0．05）。移植6个月后，患者心功能明显改善，超声心动图检查左室收缩期内径及射血分数和室壁运动积分均有明显提高（P〈0．05），6min步行距离也有明显提高（P〈0．05）。整个过程中未出现严重并发症。结论：自体干细胞冠状动脉内移植治疗老龄心肌梗死后心力衰竭，6个月时超声心动图客观指标评估能够改善患者心功能，且安全。