闭合复位空心螺钉治疗股骨颈骨折后股骨头坏死的影响因素分析

目的回顾性分析闭合复位空心螺钉治疗股骨颈骨折后股骨头坏死的影响因素。 方法对2009年1月至2017年3月293例采用加压空心螺钉治疗股骨颈骨折的患者进行回顾性分析,其中获得随访的患者247例。应用SPSS20.0软件进行统计学分析,并对影响股骨头坏死的各项因素进行Logistic回归分析。 结果247例患者获得平均58个月（24~80个月）随访,32例出现股骨头坏死,发生率12.9%,随访时髋关节Harris评分平均81.4±3.9分（54~98分）。影响股骨颈骨折术后股骨头坏死的因素和顺序依次为复位质量（OR=9.854,P=0.012）,空心钉排列方式（OR=7.965,P=0.017）,骨折分型（OR=6.453,P=0.021）,空心钉取出与否（OR=5.364,P=0.027）,术前是否牵引（OR=2.561,P=0.042）。 结论复位质量是影响股骨颈骨折预后最为关键的因素。空心螺钉正三角形排列、空心螺钉取出以及未及时术前牵引均可能加重股骨头坏死。     

Mineralocorticoid receptor antagonist-mediated cognitive improvement in a mouse model of Alzheimer's type: possible involvement of BDNF-H2S-Nrf2 signaling

The present study explored the role and mechanisms of mineralocorticoid receptor antagonists in β-amyloid (Aβ)-induced cognitive impairment. A single intracerebroventricular injection of Aβ_1-42 was given to mice, and after 14 days of injection, memory was evaluated using the Morris water maze test. Spironolactone (25 and 50 mg/kg) and eplerenone (50 and 100 mg/kg) were administered for two days before and for 14 days after Aβ injection. Mineralocorticoid receptor blockers attenuated Aβ-induced cognitive impairment assessed in terms of decrease in day 4 escape latency time (ELT) in comparison to day 1 ELT (suggesting an increase in learning) along with an increase in time spent in target quadrant on day 5 (suggesting the retrieval of learned things). These drugs also increased the expression of BDNF, H₂S, Nrf2, reduced glutathione, and decreased β-amyloid and TNF-α in the frontal cortex and hippocampus. Co-administration of ANA-12, BDNF receptor antagonist (0.25 and 0.5 mg/kg) abolished cognitive improving functions of mineralocorticoid receptor blockers, attenuated H₂S, Nrf2, reduced glutathione, and decreased β-amyloid and TNF-α. It is concluded that spironolactone and eplerenone attenuate cognitive decline of Alzheimer's type, possibly through upregulation of BDNF levels in the frontal cortex and hippocampus, which may increase H₂S, decrease Aβ, activate Nrf2-dependent antioxidant system, and decrease neuroinflammation.     

大蒜多糖预处理对缺氧缺糖/复氧复糖大鼠心肌细胞的拮抗作用

目的:研究大蒜多糖(GP)预处理对缺氧缺糖/复氧复糖损伤大鼠心肌细胞的拮抗作用研究,并初步探讨其作用机制。方法:采用连二亚硫酸钠(Na2S2O4)建立乳鼠心肌细胞糖氧剥离的A/R损伤模型,不同剂量GP(10、30和100mg/L)预处理24h后,比色法测定细胞培养液中iNOS和NO含量,测定细胞内SOD活性及MDA含量。结果:与A/R模型组比较,GP预处理可增加胞内SOD活性和培养液中iNOS活力,降低NO释放量和胞内MDA含量。结论:GP预处理对A/R损伤心肌细胞具有明显的抗氧化作用,可能与清除自由基的产生有关。     

Isolation,Characterization, and Genome Analysis of a Novel Bacteriophage,Escherichia Phage vB_EcoM-4HA13, Representing a New Phage Genus in the Novel Phage Family Chaseviridae

Shiga toxin-producing Escherichia coli (STEC) is one of the leading causes of foodborne illnesses in North America and can lead to severe symptoms, with increased fatality risk for young children. While E. coli O157:H7 remains the dominant STEC serotype associated with foodborne outbreaks, there has been an increasing number of non-O157 STEC outbreaks in recent years. For the food industry, lytic bacteriophages offer an organic, self-limiting alternative to pathogen reduction—one that could replace or reduce the use of chemical and physical food processing methods. From EHEC-enriched sewage, we isolated a novel bacteriophage, vB_EcoM-4HA13 (4HA13). Phenotypic characterizations revealed 4HA13 to possess a myoviral morphotype, with a high specificity to non-motile O111 serotype, and a long latent period (90 min). Through genomic analyses, this 52,401-bp dsDNA phage was found to contain 81 CDS, but no detectable presence of antibiotic resistance, integrase, or virulence genes. A BLASTn search for each of the identified 81 CDS yielded homologues with low levels of similarity. Comparison of RNA polymerase and terminase large subunit amino acid sequences led to the proposal and acceptance of a new bacteriophage family, Chaseviridae, with 4HA13 representing a new species and genus. The discovery of this phage has broadened our current knowledge of bacteriophage diversity.     

Grafting antibiofilm polymer hydrogel film onto catheter by SARA SI-ATRP

Abstract

Catheters are widely used and play an important role in medicine. However, catheter-associated infection is prevalent even under stringent sterile conditions. Biofilms are formed when bacteria populate the surfaces of catheters. This makes the biofilm resistant to antibiotics. Hence, it is imperative for there to be an inherently antifouling and anti-bacterial catheter to mitigate the formation of biofilm. This paper aims to outline the synthesis of non-leachable anti-biofilm and anti-bacterial cationic film coatings through direct polymerization using supplemental activator and reducing agent surface initiated atom transfer radical polymerization (SARA SI-ATRP). Three crosslinked cationic coatings comprising of Diallyl dimethyl ammonium chloride (DADMAC), or ε-poly-L-lysine HCl methacrylic acid (EPL-MA) together with a crosslinker (polyethylene glycol dimethacrylate, PEGDMA) were investigated. These non-leachable covalently linked coatings with DADMAC can achieve more than 2 log reduction (99.0%) with Methicillin-resistant Staphylococcus aureus (MRSA) and 1.25 log reduction (94.4%) with Vancomycin resistant Enterococcus (VRE) in in vitro studies.     

Baicalein reduces β‐amyloid and promotes nonamyloidogenic amyloid precursor protein processing in an Alzheimer's disease transgenic mouse model

Baicalein, a flavonoid isolated from the roots of Scutellaria baicalensis, is known to modulate γ‐aminobutyric acid (GABA) type A receptors. Given prior reports demonstrating benefits of GABA_A modulation for Alzheimer's disease (AD) treatment, we wished to determine whether this agent might be beneficial for AD. CHO cells engineered to overexpress wild‐type amyloid precursor protein (APP), primary culture neuronal cells from AD mice (Tg2576) and AD mice were treated with baicalein. In the cell cultures, baicalein significantly reduced the production of β‐amyloid (Aβ) by increasing APP α‐processing. These effects were blocked by the GABA_A antagonist bicuculline. Likewise, AD mice treated daily with i.p. baicalein for 8 weeks showed enhanced APP α‐secretase processing, reduced Aβ production, and reduced AD‐like pathology together with improved cognitive performance. Our findings suggest that baicalein promotes nonamyloidogenic processing of APP, thereby reducing Aβ production and improving cognitive performance, by activating GABA_A receptors. © 2013 Wiley Periodicals, Inc.     

Sequences and replication of genomes of the archaeal rudiviruses SIRV1 and SIRV2: relationships to the archaeal lipothrixvirus SIFV and some eukaryal viruses

The double-stranded DNA genomes of the viruses SIRV1 and SIRV2, which infect the extremely thermophilic archaeon Sulfolobus and belong to the family Rudiviridae, were sequenced. They are linear, covalently closed at the ends, and 32,312 and 35,502 bp long, respectively, with an A+T content of 75%. The genomes of SIRV1 and SIRV2 carry inverted terminal repeats of 2029 and 1628 bp, respectively, which contain multiple direct repeats. SIRV1 and SIRV2 genomes contain 45 and 54 ORFs, respectively, of which 44 are homologous to one another. Their predicted functions include a DNA polymerase, a Holliday junction resolvase, and a dUTPase. The genomes consist of blocks with well-conserved sequences separated by nonconserved sequences. Recombination, gene duplication, horizontal gene transfer, and substitution of viral genes by homologous host genes have contributed to their evolution. The finding of head-to-head and tail-to-tail linked replicative intermediates suggests that the linear genomes replicate by the same mechanism as the similarly organized linear genomes of the eukaryal poxviruses, African swine fever virus and Chlorella viruses. SIRV1 and SIRV2 both contain motifs that resemble the binding sites for Holliday junction resolvases of eukaryal viruses and may use common mechanisms for resolution of replicative intermediates. The results suggest a common origin of the replication machineries of the archaeal rudiviruses and the above-mentioned eukaryal viruses. About 1/3 of the ORFs of each rudivirus have homologs in the Sulfolobus virus SIFV of the family Lipothrixviridae, indicating that the two viral families form a superfamily. The finding of inverted repeats of at least 0.8 kb at the termini of the linear genome of SIFV supports this inference.     

1997~2007年泗洪县疟疾流行及控制

目的分析泗洪县近10年来采取的疟疾控制策略并评价其防治效果。方法收集并分析1997—2007年全县疟疾个案调查表及疟疾防治工作的历史资料和疫情资料。结果1997年泗洪县2个乡（镇）发生疟疾2例,从1998年出现疟疾疫情回升,当年发现病例21例,分布在12个乡（镇）,1999年增至65例,分布在16个乡（镇）,疫情呈散在分布,2000、2001年出现局部暴发点,全县疟疾人数分别上升到477、788例,发病率分别为4．77／万、7．78／万。通过实施传染源管理和媒介控制并重的综合性防治措施,2007年发病率下降到0．99／万,疫情趋于平稳。结论泗洪县所实施的疟疾防控措施取得了一定成效,但仍应抓好疟疾监测工作,以防疫情出现波动。     

南水北调东线工程源头地区钉螺监测

目的了解南水北调东线工程源头地区钉螺分布及其对调水安全的影响。方法每年春季采取系统抽样结合环境抽查法对东线工程源头地区进行钉螺分布调查,同时选择江都水利枢纽泵站消力池滩地定点监测钉螺扩散。结果2006-2009年东线工程源头地区查出钉螺面积分别为256.11、184.55、164.92hm2和121.16hm^2;感染性钉螺面积分别为8.3、1.0、1.0hm^2和0hm^2;活螺密度也呈逐年下降趋势。GoogleEarth地图显示东线工程源头地区钉螺主要分布在夹江和芒稻河。对江都泵站消力池滩地定点监测发现局限性低密度扩散钉螺,分析原因为引河疏浚工程建筑垃圾携带所致。结论南水北调东线源头地区存在钉螺扩散的风险,因此有必要长期开展监测和控制。