Occurrence of K1 and K2 serotypes and genotypic characteristics of extended spectrumβ-lactamases-producing Klebsiella pneumoniae isolated from selected hospitals in Malaysia

Objective:To determine the distribution,phenotypic and genetic background of extended spectrumβ-lactamases(ESBL)-producing Klebsiella(K.)pneumoniae clinical isolates associated with K1 and K2 serotypes in two selected hospitals in Malaysia.Methods:A total of 192 K.pneumoniae isolates were collected and subjected to antibiotic susceptibility,hypermucoviscosity test and multiplex PCR to detect the presence of K1-and K2-serotype associated genes.Multilocus sequence typing(MLST)was performed on ESBL-producing K.pneumoniae isolates presented with K1 and K2 serotypes,followed by phylogenetic analysis.Results:A total of 87 out of 192(45.3%)of the K.pneumoniae isolates collected were ESBL producers.However,only 8.3%(16/192)and 10.9%(21/192)of the total isolates were detected to carry K1-and K2-serotype associated genes,respectively.Statistical analysis showed that K1 and K2 capsular serotypes were not significantly associated with ESBL phenotype(P=0.196).However,they were significantly associated with hypervirulent,as demonstrated by the positive string test(P<0.001).MLST analysis revealed that ST23 as the predominant sequence type(ST)in the K1 serotype,while the ST in the K2 serotype is more diverse.Conclusions:Although the occurrence of ESBL-producing isolates among the hypervirulent strains was low,their coexistence warrants the need for continuous surveillance.MLST showed that these isolates were genetically heterogeneous.

Antibiotic Resistance Profile of Serotypes of Streptococcus pneumoniae Strains in Bangui, from 2017 to 2022: Case of Serotype 1

Goals: The aim of this study was to determine the antibiotic resistance profile of serotypes of Streptococcus pneumoniae strains circulating in Bangui. Methodology: A prospective and analytical analysis was carried out at the National Laboratory of Clinical Biology and Public Health from 2017 to 2022. The strains came from our study on the contribution to the study of antibiotic sensitivity of Streptococcus pneumoniae strains. The multiplex PCR test was used for its cost-effectiveness in terms of amplifiers which can be purified in order to be sequenced. It also makes it possible to detect several germs as well as their serotypes. For a PCR reaction, several elements are involved in the reaction medium or Master Mix. These are the desoxyribonucleotides (dNTPs), the magnesium ions (MgCl2) and the primers. A set of 14 primers divided into 3 classes were used. Class 1 primers served as an internal control by targeting the cpsA gene. It is a highly conserved gene found in capsular loci characterized to date. The primers of the second class were used to target specific serotypes by specific reactions (out of six possibilities). The group reaction was carried out using the primers of the third class in order to carry out an initial screening of the samples and to classify the pneumococcal isolates. Related serotypes were grouped based on the amplification of common genes. Using the technique of electrophoresis on agarose gel and an ultraviolet radiation device, the migration bands are then visualized and analyzed. The data collected had been entered into Excel 2010 and analyzed with Epi info 7. The exact Fischer chi2 test at the 5% threshold, the relative risk and its 95% confidence interval were used to compare the proportions and determine the associations. Results: 187 antibiotic-resistant strains of Streptococcus pneumoniae were collected. The average frequency of serotypes 1, 9A, 4 and untypeable identified were 43.59%, 18.18%, 18.27% and 39.57% respectively. The frequency of serotype 1 was predominant for the age group over five years old with 56.88%. The male sex was predominant with 55.08% for serotype 1. Resistance to penicillin and gentamicin for serotype 1 during this study, for the age group under 5 years old, was 77%. For serotypes 19A and 4, tetracycline resistance was predominant with 20% for the age group under 5 years. The resistance to penicillin and gentamicin of non-typeable serotypes was 33% for the age group under 5 years old. For the age group over 5 years old, resistance to erythromycin predominated at 37%. The distribution of serotypes by sex depending on antibiotic resistance was variable. There was a statistically significant association between identified serotypes and antibiotic resistance (p Conclusion: The study determined serotypes 1, serotypes 19A, serotypes 4 and non-typeable serotypes. These results would be due to the quality of vaccination or poor protection of vaccines.

Prevalence of Precancerous Lesions Based on Digital Cervicography with VIA/VILI among Women Positive for High-Risk Human Papillomavirus Serotypes: A Screening Center-Based Study in Cameroon

Background: Since 2021, high-risk Human Papilloma Virus (HR-HPV) testing has been the recommended screening test for cervical cancer for all settings;either used alone in a “test and treat” strategy, or with a triage test, with or without biopsy, before treatment. Cameroon has rolled out immunization against HPV 16 and 18, but studies show a higher prevalence of non-16/18 HR-HPV types. Objectives: Determine the prevalence of precancerous lesions, in women with HR-HPV infection and evaluate association of digital cervicography (DC) VIA/VILI positivity with HPV serotype, as a measure of their contribution to precancer and cancer incidence. Methodology: The study was cross-sectional, descriptive, and analytic. It took place at the Etoug-Ebe and Ekoudoum Baptist Hospitals in Yaoundé, during the period April-September 2022. We reviewed the records of women screened for cervical cancer between February 2020 and December 2021 and evaluated the prevalence of lesions on digital cervicography (DC) with VIA/VILI for women positive for HR-HPV serotypes. The data were analyzed using SPSS version 20.0 for Windows. P values Results: We identified 315 cases with a positive HR-HPV deoxyribonucleic acid (DNA) test, 224 (71.1%) had a DC VIA/VILI triage test done. Of these, 30 (13.4%) women had a positive DC VIA/VILI, with five women (2.2%) having lesions suggestive of cancer. Out of 11 cases positive for HPV 16 alone, 05 (45.5%) had a positive DC VIA/VILI test. Of the 14 cases positive for HPV 18 alone, 03 (21.4%) had a positive VIA/VILI, meanwhile only 19 (10.7%) of the 177 cases positive for non-16/18 HPV had a positive VIA/VILI test. Conclusion: A high proportion of women (13.4%) with HR HPV had a positive DC VIA/VILI, with a significant proportion (2.2%) having lesions suggestive of invasive cervical cancer HR-HPV serotype was associated with DC VIA/VILI positivity;HPV 16 had the strongest association (45.5%), followed by HPV 18 (21.4%), and non-16/18 HR-HPV (10.7%), suggesting a decreasing order of oncogenicity.

Membrane vesicles derived from Streptococcus suis serotype 2 induce cell pyroptosis in endothelial cells via the NLRP3/Caspase-1/GSDMD pathway

Streptococcus suis serotype 2(S.suis 2)is a zoonotic pathogen that clinically causes severe swine and human infections(such as meningitis,endocarditis,and septicemia).In order to cause widespread diseases in different organs,S.suis 2 must colonize the host,break the blood barrier,and cause exaggerated inflammation.In the last few years,most studies have focused on a single virulence factor and its influences on the host.Membrane vesicles(MVs)can be actively secreted into the extracellular environment contributing to bacteria-host interactions.Gram-negative bacteria-derived outer membrane vesicles(OMVs)were recently shown to activate host Caspase-11-mediated non-canonical inflammasome pathway via deliverance of OMV-bound lipopolysaccharide(LPS),causing host cell pyroptosis.However,little is known about the effect of the MVs from S.suis 2(Gram-positive bacteria without LPS)on cell pyroptosis.Thus,we investigated the molecular mechanism by which S.suis 2 MVs participate in endothelial cell pyroptosis.In this study,we used proteomics,electron scanning microscopy,fluorescence microscope,Western blotting,and bioassays,to investigate the MVs secreted by S.suis 2.First,we demonstrated that S.suis 2 secreted MVs with an average diameter of 72.04 nm,and 200 proteins in MVs were identified.Then,we showed that MVs were transported to cells via mainly dynamin-dependent endocytosis.The S.suis 2 MVs activated NLRP3/Caspase-1/GSDMD canonical inflammasome signaling pathway,resulting in cell pyroptosis,but it did not activate the Caspase-4/-5 pathway.More importantly,endothelial cells produce large amounts of reactive oxygen species(ROS)and lost their mitochondrial membrane potential under induction by S.suis 2 MVs.The results in this study suggest for the first time that MVs from S.suis 2 were internalized by endothelial cells via mainly dynamin-dependent endocytosis and might promote NLRP3/Caspase-1/GSDMD pathway by mitochondrial damage,which produced mtDNA and ROS under induction,leading to the pyroptosis of endothelial cells.

Expression and Identification of the Type-specific Antigen of FMDV of Serotype C

[Objective]The aim was to provide a theoretical basis for preparation of polyclonal antibodies and monoclonal antibody that of type specificity, as well as Foot-and-mouth Disease Virus （FMDV） typing.[Method] The recombinant plasmid pGEM-CP1 that contained VPI gene of FMDV of serotype C was used as template for the VP1 and its C terminus coding fragments of FMDV of serotypes C amplification. The coding fragments of VP1 and its C terminus were respectively cloned into prokaryotic expression vector for prokaryotic expression and the reactionogenicity was detected. The purified fusion protein of FMDV VP1 and its C terminus of serotype C were used to construct the indirect ELISA method to detect positive sera of four serotypes A, O, C and Asia 1 of guinea pig and determine the cross reactivity of FMDV antibody of VP1 and its C terminus of serotype C with other three serotypes. [ Result] The recombinant prokaryotic expression plasmids of PPRO-CVP1 and pPRO-CVPlc were constructed, FMDV VP1 and its C terminus of serotype C were expressed in high level, and the molecular weight of target proteins was 33 kD and 20 kD respectively. Western blot result showed that the fusion protein of VP1 and its C terminus could react with the positive sera of guinea pig of the same serotype. ELISA results revealed that VP1 and its C terminus of serotype C are type-specific and no cross-reactivities were shown between guinea pig positive sera of FMDV of serotype C with the other three serotypes, and the C terminus showed better type-specificity. [ Conclusion] FMDV specific antigen of serotype C was obtained.

A Method for Detecting Adhesive Related-Factors of Streptococcus suis Serotype 2 by Real-time PCR

[Objective] This study aimed to establish a method for quantitative detection of mRNA transcriptional level of SS2 adhesive related-factors of Streptococcus suis serotype 2 （SS2） by fluorescent quantitative PCR. []Vlethod] The gene fragments en- coding SS2 adhesive related-factors MRP, FBPS and CPS2J and a housekeeping gene aroA were amplified by reverse transcription PCR from the total RNA of SS2, cloned, and sequenced. The recombinant plasmids containing the target genes were constructed, and used as templates in Real-time PCR. [Result] Dynamic curves, stan- dard curves and melting curves of the adhesive related-factors and aroA were ob- tained by the optimized Real-time PCR system. The standard curves showed a good linear relationship between template copy number and circulation number, and the correlation coefficients （FF） of the standard curves were over 0.995. Also, these as- says were highly specific a^d there was single specific melting peak for every gene. Moreover, the assays were highly sensitive and had a detection limit of 1.0×102 copies in 1 μl of initial templates. Finally, it was highly repeatable and had a coeffi- cient of variation less than 2% for intra-assay. [Conclusion] This study will provide a way to reveal the adhesion mechanism of SS2 to different host cells at molecular level.

炎见宁片的定性鉴别及其苦玄参甙Ⅰ_A的含量测定

采用TLC法鉴别炎见宁片中苦玄参和毛冬青，并用双波长薄层扫描法测定了苦玄参有效成分苦玄参甙ⅠA的含量。

基于数量化理论Ⅰ的女西服款式感性评价

为了设计出符合消费者感性需求的服装产品,以女西服为研究对象,提出感性工学与数量化理论Ⅰ相结合的款式设计研究方案。首先通过语意差异法获取消费者对女西服样本的感性评价,利用SPSS软件对感性评分进行分析,提取感性因子,创建女西服二维感性分布空间。同时分析款式特征,归纳出女西服主要设计要素,在此基础上应用数量化理论Ⅰ,通过线性回归分析得出感性因子与设计要素之间的关联预测,并构建数学模型。经验证,该模型实测值与预测值之间拟合度较高,符合正态分布要求,模型有效可行。最后通过案例设计与验证,进一步证明该模型能够实现人的感性需求与女西服设计要素之间的有效转换,对女西服款式设计与感性评价提供一定借鉴作用。

重楼皂苷Ⅰ抗肿瘤作用研究进展

恶性肿瘤已成为威胁全球健康的重大难题之一。化疗和靶向治疗是其重要的药物治疗手段,但由于药物不良反应和耐药性严重影响患者的治疗依从性、生活质量和治疗效果。越来越多的研究表明,中草药是探索新型抗癌疗法的天然宝库,具有很高的医用价值。清热解毒法是中医治疗恶性肿瘤的基本法则之一。清热解毒类中草药重楼,其性微寒,味苦,有小毒,归足厥阴肝经,具有消肿止痛、清热解毒、凉肝定惊之功效。重楼主要适用于疔疮痈肿、咽喉肿痛、蛇虫咬伤、跌打损伤以及惊风抽搐等症。重楼皂苷Ⅰ是中草药重楼的有效活性成分之一,其化学结构为C_(44)H_(70)O_(16)。大量实验表明,重楼皂苷V能通过抑制肿瘤细胞增殖、阻滞细胞周期、诱导细胞凋亡自噬、逆转肿瘤耐药、抑制肿瘤血管生成、抑制肿瘤EMT、调节肿瘤微环境等途径抑制多种恶性肿瘤细胞生长。查阅国内外关于重楼皂苷Ⅰ抗肿瘤作用及机制的相关文献,对其进行归纳总结,为重楼皂苷Ⅰ抗肿瘤作用机制深入研究及抗肿瘤新药研发提供相应参考。

皖南蝮蛇毒抑瘤组分-Ⅰ对胃癌MKN-28细胞增殖、迁移及凋亡的影响

目的:探讨皖南蝮蛇毒抑瘤组分-Ⅰ(agkistrodon halys venom antitumor componentⅠ,AHVAC-Ⅰ)对胃癌MKN-28细胞生物学行为的影响作用。方法:不同实验浓度(5、10和15μg/mL)AHAVC-Ⅰ处理胃癌细胞MKN-2824 h后,采用细胞增殖和毒性检测(cell counting kit-8,CCK-8)法检测细胞增殖活力;划痕实验和Tanswell小室检测细胞迁移能力;激光共聚焦显微镜(annexin VmCherry/DAPI双染)和流式细胞术(annexin VFITC/PI双染)检测细胞凋亡;Western blot检测细胞凋亡相关蛋白Caspease-3的表达水平。结果:AHVAC-Ⅰ各浓度组分别与正常对照组相比结果显示,随着AHVAC-Ⅰ浓度的增加,MKN-28细胞增殖活力逐渐下降(P<0.01),细胞迁移能力逐渐被抑制(P<0.01),细胞凋亡率增高(P<0.05),凋亡相关蛋白Caspease-3表达上调(P<0.01)。结论:AHVAC-Ⅰ抑制胃癌细胞MKN-28增殖和迁移,诱导其凋亡。

细聚丙烯纤维混凝土介观离散力学模型及其Ⅰ型断裂强度负效应机理

细聚丙烯(PP,直径小于100μm)纤维混凝土Ⅰ型断裂强度随纤维含量增加呈现先增后减的变化规律,其机理尚不明晰。而且由于纤维数量过多,现有数值方法无法精细刻画细纤维混凝土力学行为。对此通过考虑细PP纤维亲水性提升基体局部水灰比的强度正效应和纤维桥接力强度贡献低于砂浆的强度负效应,并引入纤维直径等效系数(rf),实现介观尺度细聚丙烯纤维混凝土(PFRC)力学行为模拟。研究表明:纤维直径等效系数(rf)建议小于10;当纤维微量添加时,细PP纤维提升基体局部水灰比,使基体强度上升,此时正效应高于负效应;随着纤维含量增加,由于纤维桥接力贡献无法补偿相应面积基体强度,负效应持续增长,PFRC宏观Ⅰ型断裂强度下降。

老年高血压患者载脂蛋白A-Ⅰ与颈动脉粥样硬化的相关性分析

目的探讨老年高血压患者载脂蛋白A-Ⅰ与颈动脉粥样硬化的相关性,为老年高血压患者的危险因素进行早期干预提供参考依据。方法回顾性分析2022年4月至2023年4月于呼和浩特市第一医院门诊及住院治疗的老年高血压合并颈动脉粥样硬化患者的临床资料,将其作为观察组,另收集同期门诊及住院高血压患者的资料作为对照组。所有研究对象均进行血清载脂蛋白A-Ⅰ及颈血管彩超的检测。比较上述指标的变化情况,并分析老年高血压患者载脂蛋白A-Ⅰ与颈动脉粥样硬化的相关性。结果观察组研究对象载脂蛋白A-Ⅰ水平低于对照组,颈动脉血管彩超检查,观察颈内动脉、颈外动脉、颈总动脉的最大流速(V max)、最小流速(V min)、阻力指数RI、管径、内中膜厚度、斑块的大小、颈动脉狭窄差异均有统计学意义(P<0.05)。结论老年高血压患者载脂蛋白A-Ⅰ水平越低,颈动脉粥样硬化程度水平越高,且载脂蛋白A-Ⅰ与颈血管血流、颈动脉狭窄水平呈显著正相关。临床可应用载脂蛋白A-Ⅰ水平控制作为老年高血压合并颈动脉粥样硬化患者的早期干预指标,有助于延缓老年高血压患者颈动脉粥样硬化的发生,从而降低心脑血管病的发生率、致残率。

畅脉乐胶囊(Ⅰ)质量评价

目的对畅脉乐胶囊(Ⅰ)质量进行评价。方法分析采用ThermoScientificAccucoreTMXLC18色谱柱(4.6mm×250mm,4μm);流动相甲醇-乙腈-0.5%磷酸,梯度洗脱;体积流量1mL/min;柱温35℃;检测波长230、280nm,测定天麻素、丹参素、槲皮素-3-O-β-D-葡萄糖-7-O-β-D-龙胆双糖苷、3′-羟基葛根素、葛根素、3′-甲氧基葛根素、葛根素芹菜糖苷、芍药苷、大豆苷、迷迭香酸、紫草酸、异槲皮苷、芒柄花苷、大豆苷元、丹酚酸B、毛蕊异黄酮的含量,建立HPLC指纹图谱,测定相似度。结果16种成分在各自范围内线性关系良好(r≥0.9990),平均加样回收率87.4%~103.9%,RSD0.54%~3.10%。在230nm处,10批样品指纹图谱相似度为0.954~0.999,而在280nm处其差异较明显。3′-羟基葛根素、葛根素、3′-甲氧基葛根素、葛根素芹菜苷、大豆苷、大豆苷元是主要差异成分,芍药苷、异槲皮苷含量在各批样品中稳定。结论该方法简便、准确、可靠,可用于畅脉乐胶囊(Ⅰ)的质量控制。

辽东兰花岭地区古元古代Ⅰ型花岗岩类与辽吉A型花岗岩对比研究

辽东半岛是华北克拉通胶-辽-吉古元古代活动带的重要组成部分,古元古代经历了复杂的构造演化过程,并记录了多期岩浆-变质作用,约2.2 Ga的辽吉A型花岗岩和1.89~1.85 Ga的巨斑状花岗岩、正长岩分别标志着辽东古元古代造山作用的开端和结束。最新研究显示,2.20~2.15 Ga的岩浆作用形成了2种不同类型的花岗岩,它们可能具有不同的岩石成因和构造意义。在青城子铅锌矿集区北部采集的兰花岭、白砬子花岗闪长岩和黄泊辉绿岩,锆石U-Pb年龄分别为2177±19 Ma、2129±36 Ma、1876±29 Ma。花岗闪长岩的岩石成因类型、地球化学特征与典型的约2.2 Ga的辽吉A型花岗岩明显不同,属于弱过铝质、低钾钙碱性—碱性岩石,Zr、Hf、Nb、Rb含量较低,K_(2)O/Na_(2)O值、稀土元素总量极低,为典型的Ⅰ型花岗岩类。根据锆石Lu-Hf同位素分析,ε_(Hf)(t)值为-5.1~9.0,二阶段Hf模式年龄t_(DM2)为2089~2817 Ma,岩浆源区为约2.5 Ga的太古宙地壳物质和少量软流圈地幔物质。兰花岭地区花岗闪长岩具备岛弧或活动大陆边缘的地球化学亲缘属性,可能形成于弧岩浆俯冲挤压环境;结合形成于伸展环境的A型条痕状花岗岩特征,认为约2.2 Ga辽东地区古元古代活动带呈现总体伸展、局部挤压的构造环境,为洋壳板块向龙岗地块俯冲碰撞过程中或碰撞后的弧后盆地。

肯氏Ⅰ、Ⅱ类牙列缺损数字化印模及模型在可摘局部义齿中的应用

目的评估肯氏Ⅰ、Ⅱ类牙列缺损数字化印模及树脂模型技术在可摘局部义齿(RPD)中的应用效果。方法选择肯氏Ⅰ、Ⅱ类牙列缺损患者,按照义齿制作流程分组:数字化印模/树脂模型/钴铬合金铸造支架组(A组)、数字化印模/树脂模型/激光打印钛支架组(B组)、藻酸盐印模/石膏模型/钴铬合金铸造支架组(C组)、藻酸盐印模/石膏模型/激光打印钛支架组(D组),每组40例。对最终完成的RPD在口内就位情况进行检查,评估指标包括卡环固位力、连接体和基托在口内的密合度、咬合准确度,各项指标评估分值使用Kruskal-Wallis秩和检验进行分析。结果4组RPD各项指标的评分值差异无统计学意义。结论利用数字化印模及树脂模型完成的铸造钴铬合金和激光打印钛支架式RPD能够满足肯氏Ⅰ、Ⅱ类牙列缺损患者的临床修复要求。

MHC-Ⅱ联合MHC-Ⅰ免疫组化染色在特发性炎性肌病诊断中的应用价值探讨

目的探讨主要组织相容性复合体(MHC)-Ⅱ联合MHC-Ⅰ免疫组化染色在特发性炎性肌病(IIM)诊断中的应用价值。方法收集2010年3月至2018年4月在首都医科大学宣武医院神经内科行肌肉活检患者的标本29份,并通过医院电子病历系统收集患者的临床资料,包括4种IIM[皮肌炎(DM)5例,多发性肌炎(PM)5例,散发性包涵体肌炎(IBM)4例及坏死性自身免疫性肌病(NAM)5例]和2种非炎性肌病(NIM)[肌营养不良(MD)5例,dysferlinopathy肌病5例]。将标本进行苏木精-伊红(HE)染色及MHC-Ⅰ、MHC-Ⅱ免疫组化染色。结果免疫组化染色结果显示,PM、DM及IBM患者肌肉标本MHC-Ⅰ阳性率达100.0%,NAM和MD患者肌肉标本MHC-Ⅰ阳性率为80.0%,dysferlinopathy肌病患者肌肉标本MHC-Ⅰ阳性率为20.0%。PM和IBM患者肌肉标本MHC-Ⅱ阳性率分别为40.0%、50.0%,其余类型疾病患者肌肉标本的MHC-Ⅱ免疫组化染色均呈阴性。结论相较于MHC-Ⅰ免疫组化染色,MHC-Ⅱ免疫组化染色在鉴别IIM与NIM中有较高的特异性。MHC-Ⅱ联合MHC-Ⅰ免疫组化染色对不同肌病类型的诊断有较好的临床应用价值。

基于线粒体COⅠ基因序列的梭鲈野生群体遗传结构

为了解梭鲈种群的遗传结构,实验利用线粒体细胞色素c氧化酶Ⅰ亚基(COⅠ)基因部分序列分析了中国6个和中亚2个群体的遗传差异,并与欧洲群体的单倍型序列进行了比较。结果在640 bp的COⅠ基因序列中检测到5个变异位点,定义了7种单倍型,发现Hap1为8个梭鲈群体的共享单倍型,且与欧洲群体的HapA相同,在中国群体所占比例(93.36%)高于中亚群体(72.58%)和欧洲群体(53.85%);Hap2和Hap3是中国群体的特异单倍型,而Hap4~Hap7为中亚群体的特异单倍型。单倍型序列的聚类图和网络图均显示Hap1/A为梭鲈群体的原始单倍型,中国和中亚群体的特异单倍型相对于原始单倍型仅有1~2个位点的变异,属于Hap1/A的亚型,与欧洲群体的特异单倍型具有较大的差异。每个群体检测到1~4种单倍型,斋桑湖(ZS)群体单倍型最多,而中国的腾格里湖(NX)、兴凯湖(XK)和鸭绿江(YJ)群体仅有1个单倍型(Hap1);塔什干(TS)群体的单倍型多样性(Hd)和核苷酸多样性(π)最高(Hd=0.514±0.069;π=0.00079±0.00011),其次是ZS群体,而中国梭鲈群体的多样性参数较低。AMOVA分析结果显示,梭鲈群体间遗传变异占20.74%,群体间遗传分化程度较高(0.15≤F_(st)=0.20736<0.25),TS群体与ZS群体和中国群体间的遗传分化极大(F_(st)>0.25),中国群体中仅黑河(HH)群体与其他群体的遗传分化较大,而中国其他5个群体间无遗传分化。基于群体间遗传距离的系统进化树显示,来自中国的6个梭鲈群体与哈萨克斯坦的ZS群体聚为一支,而乌兹别克斯坦的TS群体独立为一支。研究结果为梭鲈群体的繁殖及放流管理提供了参考。

基于ABAQUS平台考虑T应力的Ⅰ型裂纹扩展模拟开发

工程结构在制造工艺过程中或使用期间会产生裂纹,对结构断裂路径的预测和研究是防治工程安全问题发生的重要手段。在考虑裂纹尖端应力场常数项T应力的基础上对传统的最大周向应力准则(Maximum tangential stress criterion,MTS)和最小应变能密度因子准则(Minimum strain energy density criterion,SED)进行修正,采用Python语言对ABAQUS的前、后处理和有限元计算模块进行二次开发,通过计算最优解的粒子群算法(Particle swarm optimization,PSO)将修正后的准则编入裂纹自动扩展程序脚本中。利用上述二次开发程序对初始纯Ⅰ型裂纹的扩展路径进行模拟,结果表明:采用ABAQUS脚本程序模拟结果与相关文献实验结果吻合,表明了程序的有效性,进而实现考虑T应力的多种断裂准则对裂纹扩展路径的预测;当T应力值处于一定范围内时,修正的MTS准则无法预测裂纹发生的偏转现象,扩展路径呈直线,此时可采用修正的SED准则进行预测。

“心衰Ⅰ号”辅助治疗急性心肌梗死后心力衰竭30例临床研究

目的:观察在常规西药治疗基础上加用中药汤剂“心衰Ⅰ号”对急性心肌梗死(AMI)后心功能不全气阴两虚、痰瘀痹阻证患者临床症状、心脏超声指标等的影响,并探索其可能的作用机制。方法:将60例急性心肌梗死后心功能不全气阴两虚、痰瘀痹阻证患者按区组分组方法随机分为治疗组与对照组,每组30例。对照组予常规西药抗血小板、调脂等治疗,治疗组在对照组治疗的基础上加用中药汤剂“心衰Ⅰ号”口服,2组均治疗8周后观察疗效。比较2组患者治疗前后中医证候积分、心脏超声指标以及血清微小核糖核酸(mi R)-133a、转化生长因子(TGF)-β1、结缔组织生长因子(CTGF)水平变化情况,治疗后评价2组患者中医证候疗效,观察治疗期间与治疗药物相关的不良反应发生情况。结果:治疗后2组患者气短、乏力、心悸等各项中医证候积分和总分均明显低于本组治疗前(P<0.01),治疗组患者各单项积分和总分治疗前后差值与对照组比较差异均有统计学意义(P<0.05,P<0.01),治疗组对患者中医证候的改善明显优于对照组。心脏超声指标检测结果显示,治疗后治疗组患者左室舒张末期内径(LVIDd)、左室收缩末期内径(LVIDs)均明显低于治疗前(P<0.01),对照组患者LVIDs明显低于治疗前(P<0.05),2组患者每搏输出量(SV)、左室短轴缩短率(FS)、左室射血分数(LVEF)均明显高于本组治疗前(P<0.05,P<0.01);治疗组患者LVIDs、SV、FS、LVEF治疗前后差值与对照组比较差异有统计学意义(P<0.05),治疗组对上述指标的改善明显优于对照组。治疗后治疗组患者血清mi R-133a、TGF-β1、CTGF水平均明显低于治疗前(P<0.05,P<0.01),对照组患者mi R-133a表达明显低于治疗前(P<0.05);治疗组患者上述指标治疗前后差值与对照组比较差异均有统计学意义(P<0.05),治疗组对上述指标的改善明显优于对照组。治疗后治疗组中医证候总有效率为96.67%,明显高于对照组的90.00%(P<0.05)。2组患者治疗前后血常规、尿常规、粪常规、肝肾功能等指标均未出现明显异常,治疗过程中均未发生严重的皮肤黏膜淤青、黑便、肌痛、恶心呕吐等不良事件。结论:在常规西药治疗的基础上加用中药汤剂“心衰Ⅰ号”能有效改善AMI后心功能不全患者的中医证候,有效减轻临床症状,改善心脏超声各项指标,考虑其作用机制可能与调节血清mi R-133a/TGF-β1/CTGF信号通路,改善心肌纤维化,减轻心室重构有关,且药物安全性高,值得进一步研究。

Ⅰ群4型禽腺病毒Y17215-1株体外增殖规律及免疫原性研究

为探讨禽腺病毒4型分离株Y17215-1的体外增殖特性和免疫原性,本研究以LMH细胞为模型,摸索Y17215-1株最佳接种剂量和收获时间;通过活毒滴鼻接种和灭活疫苗肌肉注射的方式免疫SPF鸡,测定其免疫原性。结果显示:Y17215-1株0.1 MOI接种LMH细胞,培养48~72 h病毒滴度达到峰值108.625 TCID_(50)/mL。该病毒经肌肉注射对42日龄SPF鸡具有较强致病性,LD_(50)为103.000 TCID_(50)/0.2 mL。以10^(7.676) TCID_(50)的Y17215-1株滴鼻免疫21日龄SPF鸡,免疫后7 d 100%试验鸡产生中和抗体,14 d达到高峰。以Y17215-1株制备灭活疫苗肌肉注射免疫21日龄SPF鸡(10^(7.676) TCID_(50)/羽),免疫后7 d 70%试验鸡产生中和抗体,21 d达到高峰。在免疫后21 d用1000LD_(50)的Y17215-1株进行攻毒,活毒和灭活疫苗的保护率均为100%。以上结果表明:Y17215-1株具有很好的体外增殖特性和免疫原性,可以作为候选疫苗毒株。