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1.
《Molecular therapy》2022,30(5):1966-1978
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2.
目的 通过对东天山区域10个县、市、区开展中药资源调查,了解该地区药用植物资源及其多样性,为合理开发和可持续利用该地区中药资源提供依据。方法 按《全国中药资源普查技术规范》开展调查工作,并与第三次全国中药资源普查相关数据进行对比。结果 共调查野外样地360个1413套8478个样方。采集到腊叶标本13 455份,包含77科339属761种,其中蕨类6科7属8种、裸子植物3科5属16种、被子植物68科327属737种。结论 东天山药用植物受其独特的地理环境影响,南坡与北坡植被类型不同,形成了独有的药用植物资源分布特点。该地区重点特色品种有甘草、贝母、阜康阿魏、麻黄、紫草、琐琐葡萄等,资源量与第三次全国中药资源普查相比均大幅下降;而栽培肉苁蓉资源量大幅上升。  相似文献   
3.
《Saudi Pharmaceutical Journal》2022,30(11):1572-1588
Non-alcoholic fatty liver disease (NAFLD) is one of the most common complications of a metabolic syndrome caused by excessive accumulation of fat in the liver. Orthosiphon stamineus also known as Orthosiphon aristatus is a medicinal plant with possible potential beneficial effects on various metabolic disorders. This study aims to investigate the in vitro inhibitory effects of O. stamineus on hepatic fat accumulation and to further use the computational systems pharmacology approach to identify the pharmacokinetic properties of the bioactive compounds of O. stamineus and to predict their molecular mechanisms against NAFLD. Methods: The effects of an ethanolic extract of O. stamineus leaves on cytotoxicity, fat accumulation and antioxidant activity were assessed using HepG2 cells. The bioactive compounds of O. stamineus were identified using LC/MS and two bioinformatics databases, namely the Traditional Chinese Medicine Integrated Database (TCMID) and the Bioinformatics Analysis Tool for the Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM). Pathway enrichment analysis was performed on the predicted targets of the bioactive compounds to provide a systematic overview of the molecular mechanism of action, while molecular docking was used to validate the predicted targets. Results: A total of 27 bioactive compounds corresponding to 50 potential NAFLD-related targets were identified. O. stamineus exerts its anti-NAFLD effects by modulating a variety of cellular processes, including oxidative stress, mitochondrial β-oxidation, inflammatory signalling pathways, insulin signalling, and fatty acid homeostasis pathways. O. stamineus is significantly targeting many oxidative stress regulators, including JNK, mammalian target of rapamycin (mTOR), NFKB1, PPAR, and AKT1. Molecular docking analysis confirmed the expected high affinity for the potential targets, while the in vitro assay indicates the ability of O. stamineus to inhibit hepatic fat accumulation. Conclusion: Using the computational systems pharmacology approach, the potentially beneficial effect of O. stamineus in NAFLD was indicated through the combination of multiple compounds, multiple targets, and multicellular components.  相似文献   
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目的:分析关于芦可替尼联合激素一线治疗初诊中高危急性移植物抗宿主病(a GVHD)疗效(NCT04061876)的单臂、开放性临床试验患者,一线治疗前后外周血中淋巴亚群尤其是髓系来源抑制细胞(MDSC)的动力学特征。方法:前瞻性观察本院23例采用芦可替尼联合激素一线治疗的中高危a GVHD患者的疗效,同时监测其淋巴细胞亚群和MDSC的变化特征,并与20例allo-HSCT后无a GVHD及23例采用激素一线治疗的a GVHD患者进行比较。结果:23例中高危a GVHD患者采用芦可替尼联合激素一线治疗后28 d的CR率为78.26%(18/23)。治疗28 d后,患者外周血中CD4+CD29+T细胞(P=0.08)含量低于治疗前,而研究中监测的其他淋巴细胞亚群的含量均高于治疗前;与难治性a GVHD患者相比,CR患者外周血中CD4+CD29+T细胞呈下降趋势。治疗28 d后,a GVHD患者外周血中CD8+CD28-T细胞(P=0.03)及CD8+CD28-T/CD8+CD28+T细胞的比值(P=0.03)明显高于allo-HSCT后无a GVHD患者。alloHSCT后,a GVHD患者外周血中粒系MDSC(G-MDSC)含量均低于无a GVHD患者,allo-HSCT后14 d差异最为显著(P=0.04)。按一线治疗疗效分层,CR患者治疗后3、7 d外周血中单核系MDSC(M-MDSC)的含量较治疗前增高(P3=0.01,P7=0.03),治疗后28 d患者外周血中e-MDSC的含量较治疗前增高(P=0.01);难治性a GVHD患者治疗后3 d外周血中M-MDSC的含量较CR患者低(P=0.01),治疗后28 d患者外周血中e-MDSC的含量较CR患者低(P=0.01);按照治疗方案进行对比分析,结果显示芦可替尼组MDSC各亚群的含量较激素组高,以M-MDSC差异最为显著(P3=0.0351;P7=0.0142;P14=0.0369)。结论:芦可替尼联合激素一线治疗a GVHD患者在获得较高的CR率的同时对allo-HSCT后患者的免疫重建的影响较小。a GVHD患者采用芦可替尼联合激素一线治疗后,外周血MDSC含量的增高提示,a GVHD患者对该治疗方案具有良好的反应性,且M-MDSC变化早于e-MDSC、G-MDSC。  相似文献   
6.
Xylella fastidiosa (Xf) is a plant pathogen causing significant losses in agriculture worldwide. Originating from America, this bacterium caused recent epidemics in southern Europe and is thus considered an emerging pathogen. As the European regulations do not authorize antibiotic treatment in plants, alternative treatments are urgently needed to control the spread of the pathogen and eventually to cure infected crops. One such alternative is the use of phage therapy, developed more than 100 years ago to cure human dysentery and nowadays adapted to agriculture. The first step towards phage therapy is the isolation of the appropriate bacteriophages. With this goal, we searched for phages able to infect Xf strains that are endemic in the Mediterranean area. However, as Xf is truly a fastidious organism, we chose the phylogenetically closest and relatively fast-growing organism X. albineans as a surrogate host for the isolation step. Our results showed the isolation from various sources and preliminary characterization of several phages active on different Xf strains, namely, from the fastidiosa (Xff), multiplex (Xfm), and pauca (Xfp) subspecies, as well as on X. albilineans. We sequenced their genomes, described their genomic features, and provided a phylogeny analysis that allowed us to propose new taxonomic elements. Among the 14 genomes sequenced, we could identify two new phage species, belonging to two new genera of the Caudoviricetes order, namely, Usmevirus (Podoviridae family) and Subavirus (Siphoviridae family). Interestingly, no specific phages could be isolated from infected plant samples, whereas one was isolated from vector insects captured in a contaminated area, and several from surface and sewage waters from the Marseille area.  相似文献   
7.
钟小清  卢志标  唐倩  吕高荣  邹节明 《中草药》2021,52(4):1151-1155
目的对壮药红根草进行了基原调查和生药学鉴定研究。方法查阅本草文献对红根草原植物记载及附图,野外调查红根草药材的原植物来源,通过产地药农收集红根草药材原植物标本,核对药材原植物标本,咨询分类专家,对红根草的原植物形态、药材性状、显微特征、薄层色谱等进行了研究。结果目前产地及市场红根草药材原植物来源是唇形科植物黄埔鼠尾草S. prionitis带根的全草,采用建立的方法能够有效鉴别红根草药材。结论为更好地制定红根草新的药材质量标准和药厂红根草药材收购提供依据。  相似文献   
8.
目的分析2005~2019年湖北省肾综合征出血热(HFRS)疫情流行特征,为制定预防控制措施提供科学依据。方法收集2005~2019年湖北省HFRS的疫情资料和鼠监测资料,开展描述性分析和相关分析。结果湖北省2005~2019年HFRS年平均发病率为0.56/10万,发病高峰为每年5~7月、11月至次年1月,2016年以后病例数上升明显,病例以男性、农民为主,35~69岁人群占79.93%,其中60岁及以上的占27.75%(1354/4879)。2019年湖北省HFRS发病率居前五位的地市为潜江市(6.21/10万)、天门市(4.01/10万)、荆州市(3.01/10万)、仙桃市(2.28/10万)和荆门市(2.04/10万)。发病率和鼠密度呈正相关(r_s=0.57,P<0.05)。结论近年来湖北省HFRS疫情有所回升,应重点关注潜江市、天门市和荆州市等江汉平原地区和60岁及以上人群,开展"监测、健教、灭鼠、免疫"并重的综合性防控措施。  相似文献   
9.
《Vaccine》2021,39(33):4742-4750
Allogeneic hematopoietic stem cell transplantation (alloHSCT) results in a loss of humoral immunity and subsequent risk for severe infections. Thus, re-vaccination is required but may fail due to incomplete immune reconstitution. We retrospectively analyzed predictors of immune response to primary vaccination applied according to the EBMT (European Blood and Marrow Transplantation Group) recommendations. Serologic response to vaccination against diphtheria (D), tetanus (T), Bordetella pertussis (aP) and Haemophilus influenzae (Hib) (administrated as combined DTaP-Hib-IPV vaccination) was studied in 84 alloHSCT patients transplanted between 2008 and 2015 (age at alloHSCT: 18.6–70.6 years). All patients with a relapse-free survival of ≥9 months, at least 3 consecutive vaccinations and absence of intravenous immunoglobulin administration within 3 months before and after vaccination met the primary inclusion criteria. Additionally, immunological response to a pneumococcal conjugate vaccine was analyzed in a subgroup of 67 patients. Patients’ characteristics at the time of first vaccination were recorded. Responses were measured as vaccine-specific antibody titers. Regarding DTaP-Hib-IPV vaccination, 89.3% (n = 75) of all patients achieved protective titers to at least 3 of the 4 vaccine components and were thus considered responders. 10.7% (n = 9) of the patients were classified as non-responders with positive immune response to less than 3 components. Highest response was observed for Hib (97.4%), tetanus (95.2%) and pneumococcal vaccination (83.6%) while only 68.3% responded to vaccination against Bordetella pertussis. Significant risk factors for failure of vaccination response included low B cell counts (p < 0.001; cut-off: 0.05 B cells/nl) and low IgG levels (p = 0.026; mean IgG of responders 816 mg/dl vs. 475 mg/dl of non-responders). Further, a trend was observed that prior cGvHD impairs vaccination response as 88.9% of the non-responders but only 54.7% of the responders had prior cGvHD (p = 0.073). The results demonstrate, that the currently proposed vaccination strategy leads to seroprotection in the majority of alloHSCT patients.  相似文献   
10.
Arthropod-borne flaviviruses, such as Zika virus (ZIKV), Usutu virus (USUV), and West Nile virus (WNV), are a growing cause of human illness and death around the world. Presently, no licensed antivirals to control them are available and, therefore, search for broad-spectrum antivirals, including host-directed compounds, is essential. The PI3K/Akt pathway controls essential cellular functions involved in cell metabolism and proliferation. Moreover, Akt has been found to participate in modulating replication in different viruses including the flaviviruses. In this work we studied the interaction of flavivirus NS5 polymerases with the cellular kinase Akt. In vitro NS5 phosphorylation experiments with Akt showed that flavivirus NS5 polymerases are phosphorylated and co-immunoprecipitate by Akt. Polymerase activity assays of Ala- and Glu-generated mutants for the Akt-phosphorylated residues also indicate that Glu mutants of ZIKV and USUV NS5s present a reduced primer-extension activity that was not observed in WNV mutants. Furthermore, treatment with Akt inhibitors (MK-2206, honokiol and ipatasertib) reduced USUV and ZIKV titers in cell culture but, except for honokiol, not WNV. All these findings suggest an important role for Akt in flavivirus replication although with specific differences among viruses and encourage further investigations to examine the PI3K/Akt/mTOR pathway as an antiviral potential target.  相似文献   
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