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1.
目的 建立纤溶酶反相高效液相色谱纯度测定方法。方法 采用SHISEIDO CAPCELL PAK C18 SG300(250 mm×4.6 mm,5 μm),以0.1%三氟乙酸溶液-乙腈(95:5)为流动相A,以0.08%三氟乙酸溶液-乙腈(20:80)为流动相B,进行梯度洗脱,体积流量为0.7 mL·min-1,检测波长280 nm,柱温40℃。参照2020年版《中国药典》四部9101药品质量标准分析方法验证指导原则进行专属性、检测限、耐用性考察。应用所建立的方法和分子排阻色谱法对3批样品纯度进行检测。结果 建立的反相色谱法专属性强,检测限为0.01%,耐用性强。对3批样品进行检测,质量分数在93.5%~96.9%,结果准确。结论 建立反相色谱法测定纤溶酶纯度,分辨率更高、重现性更好,可进行更好的质量控制。 相似文献
2.
Mitsuhiro Yamada 《Respiratory investigation》2021,59(3):302-311
Alveoli are the basic structure of the lungs, consisting of various types of parenchymal and bone marrow-derived cells including alveolar macrophages. These various types of cells have several important functions; thus, communication between these cells plays an important role in homeostasis as well as in the pathophysiology of diseases in the lungs. For a better understanding of the pathophysiology of lung diseases, researchers have isolated each type of lung cell to investigate the changes in their gene expressions, including their humoral factor or adhesion molecules, to reveal the intercellular communication among these cells. In particular, investigations during the past decade have focused on extracellular vesicles, which are lipid bilayer delimited vesicles released from a cell that can move among various cells and transfer substances, including microRNAs, mRNAs and proteins, thus, functioning as intercellular messengers. Extracellular vesicles can be classified into three general groups: apoptotic bodies, exosomes, and microparticles. Extracellular vesicles, especially exosomes and microparticles, are attracting increasing attention from pulmonologists as tools for understanding pathogenesis and disease diagnosis. Here, we review studies, including our own, on exosomes and microparticles and their roles in both lung homeostasis and the pathogenesis of lung diseases such as idiopathic pulmonary fibrosis, chronic obstructive lung diseases, and acute respiratory distress syndrome. This review also addresses the roles of extracellular vesicles in COVID-19, the current global public health crisis. 相似文献
3.
目的探讨细胞色素P450药物代谢酶(CYP)2C19基因分型与氯吡格雷治疗的急性缺血性脑卒中患者再发脑卒中的关系。方法选取2018年5月—2018年12月常州市第一人民医院收治接受氯吡格雷治疗的159例急性缺血性脑卒中患者,检测患者入院后空腹外周血中CYP2C19*2,CYP2C19*3基因分型。对患者进行随访,随访截至2020年2月,观察再发脑卒中的情况,并分析CYP2C19*2,CYP2C19*3基因分型与再发脑卒中关系。结果随访时间14~22个月,平均随访时间为(18.2±1.5)个月,共7例患者失访,共20例(13.2%)患者复发缺血性脑卒中。再发脑卒中患者中CYP2C19*2 GG型及CYP2C19*3 GG型均低于无复发患者(P<0.05),CYP2C19*2 GA型,CYP2C19*2 AA型CYP2C19*3 GA型,CYP2C19*3AA型均高于无复发患者(P<0.05)。Kaplan-Meier法并Log-rank检验结果显示,CYP2C19*2 GG型无复发时间长于AA型,差异有统计学意义(Log-rank=6.759,P=0.034)。CYP2C19*3GG型无复发时间长于AA型,差异有统计学意义(Log-rank x2=8.660,P=0.013)。多因素Cox分析结果显示,糖尿病、氯吡格雷抵抗,CYP2C19*2及CYP2C19*3基因型是再发脑卒中影响因素(P<0.05)。结论在接受氯吡格雷治疗急性缺血性脑卒中患者中,CYP2C19*2及CYP2C19*3突变型再发脑卒中的风险明显增高。 相似文献
4.
Wattana Leowattana Tawithep Leowattana Pathomthep Leowattana 《World Journal of Clinical Cases》2022,10(34):12470-12483
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered a widespread outbreak since December 2019. The SARS-CoV-2 infection-related illness has been dubbed the coronavirus disease 2019 (COVID-19) by the World Health Organization. Asymptomatic and subclinical infections, a severe hyper-inflammatory state, and mortality are all examples of clinical signs. After attaching to the angiotensin converting enzyme 2 (ACE2) receptor, the SARS-CoV-2 virus can enter cells through membrane fusion and endocytosis. In addition to enabling viruses to cling to target cells, the connection between the spike protein (S-protein) of SARS-CoV-2 and ACE2 may potentially impair the functionality of ACE2. Blood pressure is controlled by ACE2, which catalyzes the hydrolysis of the active vasoconstrictor octapeptide angiotensin (Ang) II to the heptapeptide Ang-(1-7) and free L-Phe. Additionally, Ang I can be broken down by ACE2 into Ang-(1-9) and metabolized into Ang-(1-7). Numerous studies have demonstrated that circulating ACE2 (cACE2) and Ang-(1-7) have the ability to restore myocardial damage in a variety of cardiovascular diseases and have anti-inflammatory, antioxidant, anti-apoptotic, and anti-cardiomyocyte fibrosis actions. There have been some suggestions for raising ACE2 expression in COVID-19 patients, which might be used as a target for the creation of novel treatment therapies. With regard to this, SARS-CoV-2 is neutralized by soluble recombinant human ACE2 (hrsACE2), which binds the viral S-protein and reduces damage to a variety of organs, including the heart, kidneys, and lungs, by lowering Ang II concentrations and enhancing conversion to Ang-(1-7). This review aims to investigate how the presence of SARS-CoV-2 and cACE2 are related. Additionally, there will be discussion of a number of potential therapeutic approaches to tip the ACE/ACE-2 balance in favor of the ACE-2/Ang-(1-7) axis. 相似文献
5.
目的 基于TCA循环(三羧酸循环,tricarboxylic acid cycle)关键酶测定研究督灸治疗早期强直性脊柱炎(AS)肾虚督寒证患者关节活动度的疗效及生物学机制。方法 110例早期AS肾虚督寒证患者随机分为观察组和对照组,各55例。对照组口服甲氨蝶呤+洛索洛芬钠,观察组在对照组治疗基础上给予督灸,疗程均为12周。观察治疗前后患者的病情活动指数(bath ankylosing spondylitis disease activity index,BASDAI)、功能指数(bath ankylosing spondylitis fundation index,BASFI)、活动度衡量指数(bath ankylosing measure index activity index,BASMI)、总和指数(bath ankylosing spondylitis patient slobal,BAS-G)、指-地距、枕-墙距、胸廓活动度、Schober试验水平和早期AS肾虚督寒证中医辨证(肾虚督寒证)评分;检测血清炎症因子肿瘤坏死因子-α(TNF-α)、白细胞介素-18(IL-18)、血沉(ESR)和C-反应蛋白(CRP)含量;检测TCA循环关键酶柠檬酸合成酶(citrate synthase,CS)、异柠檬酸脱氢酶(isocitrate dehydrogenase,IDH)及α-酮戊二酸脱氢酶(α-ketoglutarate dehydrogenase,α-KGDHC)的水平;比较治疗12周患者的临床疗效及随访6个月复发率。结果 临床研究过程脱落6例。观察组总有效率96.2%,明显高于观察组的82.4%(P<0.05);观察组随访6个月复发率5.7%,明显低于对照组的21.6%(P<0.05)。治疗12周后,观察组患者BASDAI、BASFI、BASMI、BAS-G、指-地距、枕-墙距和肾虚督寒证评分较对照组明显下降(P<0.05),胸廓活动度和Schober试验较对照组明显升高(P<0.05);观察组患者TNF-α、IL-18、ESR、CRP、CS和IDH水平较对照组明显下降(P<0.05),α-KGDHC水平较对照组明显升高(P<0.05)。结论 督灸可以有效改善早期AS肾虚督寒证患者的临床症状,复发率低,值得临床推广应用。 相似文献
6.
《Vaccine》2022,40(6):934-944
Respiratory Syncytial Virus (RSV) remains a leading cause of severe respiratory disease for which no licensed vaccine is available. We have previously described the derivation of an RSV Fusion protein (F) stabilized in its prefusion conformation (preF) as vaccine immunogen and demonstrated superior immunogenicity in naive mice of preF versus wild type RSV F protein, both as protein and when expressed from an Ad26 vaccine vector. Here we address the question if there are qualitative differences between the two vaccine platforms for induction of protective immunity. In naïve mice, both Ad26.RSV.preF and preF protein induced humoral responses, whereas cellular responses were only elicited by Ad26.RSV.preF. In RSV pre-exposed mice, a single dose of either vaccine induced cellular responses and strong humoral responses. Ad26-induced RSV-specific cellular immune responses were detected systemically and locally in the lungs. Both vaccines showed protective efficacy in the cotton rat model, but Ad26.RSV.preF conferred protection at lower virus neutralizing titers in comparison to RSV preF protein. Factors that may contribute to the protective capacity of Ad26.RSV.preF elicited immunity are the induced IgG2a antibodies that are able to engage Fcγ receptors mediating Antibody Dependent Cellular Cytotoxicity (ADCC), and the induction of systemic and lung resident RSV specific CD8 + T cells. These data demonstrate qualitative improvement of immune responses elicited by an adenoviral vector based vaccine encoding the RSV preF antigen compared to the subunit vaccine in small animal models which may inform RSV vaccine development. 相似文献
7.
Ursula Altanerova Jana Jakubechova Katarina Benejova Petra Priscakova Martin Pesta Pavel Pitule Ondrej Topolcan Juraj Kausitz Martina Zduriencikova Vanda Repiska Cestmir Altaner 《International journal of cancer. Journal international du cancer》2019,144(4):897-908
The natural behavior of mesenchymal stem cells (MSCs) and their exosomes in targeting tumors is a promising approach for curative therapy. Human tumor tropic mesenchymal stem cells (MSCs) isolated from various tissues and MSCs engineered to express the yeast cytosine deaminase::uracil phosphoribosyl transferase suicide fusion gene (yCD::UPRT-MSCs) released exosomes in conditional medium (CM). Exosomes from all tissue specific yCD::UPRT-MSCs contained mRNA of the suicide gene in the exosome's cargo. When the CM was applied to tumor cells, the exosomes were internalized by recipient tumor cells and in the presence of the prodrug 5-fluorocytosine (5-FC) effectively triggered dose-dependent tumor cell death by endocytosed exosomes via an intracellular conversion of the prodrug 5-FC to 5-fluorouracil. Exosomes were found to be responsible for the tumor inhibitory activity. The presence of microRNAs in exosomes produced from naive MSCs and from suicide gene transduced MSCs did not differ significantly. MicroRNAs from yCD::UPRT-MSCs were not associated with therapeutic effect. MSC suicide gene exosomes represent a new class of tumor cell targeting drug acting intracellular with curative potential. 相似文献
8.
Jipeng Wang Tianqi Wang Weifang Ding Jitao Wu Gang Wu Yongqiang Wang Zhongbao Zhou Ling Xu Yuanshan Cui 《Andrologia》2019,51(10)
Antioxidants were proved to be efficient to improve the quality of spermatozoa after varicocelectomy. We carried out a systematic review and performed a meta‐analysis to evaluate the efficacy of antioxidant therapy in sperm parameters' quality after varicocelectomy during 3 or 6 months' treatment cycle. During research, randomised controlled trials were searched by MEDLINE, EMBASE and the Cochrane Controlled Trials Register, and necessary parameters were compared between two groups after varicocelectomy. Finally, six studies including 576 patients were included in our meta‐analysis. As for sperm parameters, significant improvements of sperm concentration (p < .0001), sperm motility (p = .03), progressive sperm motility (p < .00001) and sperm morphology (p < .00001) were existed in antioxidant group 3 months after varicocelectomy. With regard to the 6 months' outcomes, sperm parameters were improved as well except sperm motility (p = .72) and progressive sperm motility (p = .57). Referring to pregnancy rate, no significant difference was existed between two groups (p = .36), and the FSH level of antioxidant group was lower than placebo group 3 or 6 months after varicocelectomy (3 months, p = .02; 6 months, p = .03). In conclusion, compared with the placebo, the antioxidant therapy after varicocelectomy can improve the quality of sperm parameters and construct a favourable living condition for spermatozoa by reducing FSH level. 相似文献
9.
10.
《Vaccine》2019,37(44):6707-6713
BackgroundPrevious studies have suggested that statins decrease influenza vaccine effectiveness and increase risk of medically attended acute respiratory illness (MAARI).ObjectivesTo examine the association of incident statin use and MAARI in a cohort of influenza vaccine recipients.MethodsThis retrospective cohort study evaluated influenza vaccine recipients within the Tricare population. The primary outcome compared MAARI incidence during the follow-up period in a propensity score-matched cohort of incident statin users and statin non-users. Secondary analysis included propensity score-adjusted comparisons between incident statin users and statin non-users in the entire cohort and prespecified sub-cohorts with and without comorbidities. The propensity score was derived from 72 variables encompassing demographics, medical history, comorbidities, medication use, and healthcare utilization.ResultsMAARI incidence in statin users was similar to non-users in the propensity score-matched cohort (odds ratio [OR] 0.92; 95% confidence interval [CI] 0.84–1.01). In contrast, statin users with lower comorbidity had lower OR for MAARI compared to non-users (Charlson Score zero cohort: 0.85 [CI 0.74–0.98]; No Diabetes cohort: 0.88 [CI 0.80–0.96]).ConclusionIncident statin use was not associated with increased MAARI incidence and may be associated with lower incidence of MAARI in those with less comorbidity. This study thus offers reassurance regarding the effectiveness of the influenza vaccine in statin users. 相似文献