Systematic analysis of DNA polymerases as therapeutic targets in pan-cancers

Introduction:DNA polymerases are crucial for maintaining genome stability and influencing tumorigenesis.However,the clinical implications of DNA polymerases in tumorigenesis and their potential as anti-cancer therapy targets are not well understood.Methods:We conducted a systematic analysis using TCGA Pan-Cancer Atlas data and Gene Set Cancer Analysis results to examine the expression profiles of 15 DNA polymerases(POLYs)and their clinical correlations.We also evaluated the prognostic value of POLYs by analyzing their expression levels in relation to overall survival time(OS)using Kaplan-Meier survival curves.Additionally,we investigated the correlations between POLY expression and immune cells,DNA damage repair(DDR)pathways,and ubiquitination.Drug sensitivity analysis was performed to assess the relationship between POLY expression and drug response.Results:Our analysis revealed that 14 out of 15 POLYs exhibited significantly distinct expression patterns between tumor and normal samples across most cancer types,except for DNA nucleotidylexotransferase(DNTT).Specifically,POLD1 and POLE showed elevated expression in almost all cancers,while POLQ exhibited high expression levels in all cancer types.Some POLYs showed heightened expression in specific cancer subtypes,while others exhibited low expression.Kaplan-Meier survival curves demonstrated significant prognostic value of POLYs in multiple cancers,including PAAD,KIRC,and ACC.Cox analysis further validated these findings.Alteration patterns of POLYs varied significantly among different cancer types and were associated with poorer survival outcomes.Significant correlations were observed between the expression of POLY members and immune cells,DDR pathways,and ubiquitination.Drug sensitivity analysis indicated an inverse relationship between POLY expression and drug response.Conclusion:Our comprehensive study highlights the significant role of POLYs in cancer development and identifies them as promising prognostic and immunological biomarkers for various cancer types.Additionally,targeting POLYs therapeutically holds promise for tumor immunotherapy.

Predictions in Clinical Efficiency of SARS-CoV-2 RNA-Dependent RNA Polymerase (RdRp) Inhibitors by Molecular Docking

This study utilizes the enzyme-substrate complex theory to predict the clinical efficacy of COVID-19 treatments at the biological systems level, using molecular docking stability indicators. Experimental data from the Protein Data Bank and molecular structures generated by AlphaFold 3 were used to create macromolecular complex templates. Six templates were developed, including the holo nsp7-nsp8-nsp12 (RNA-dependent RNA polymerase) complex with dsRNA primers (holo-RdRp-RNA). The study evaluated several ligands—Favipiravir-RTP, Remdesivir, Abacavir, Ribavirin, and Oseltamivir—as potential viral RNA polymerase inhibitors. Notably, the first four of these ligands have been clinically employed in the treatment of COVID-19, allowing for comparative analysis. Molecular docking simulations were performed using AutoDock 4, and statistical differences were assessed through t-tests and Mann-Whitney U tests. A review of the literature on COVID-19 treatment outcomes and inhibitors targeting RNA polymerase enzymes was conducted, and the inhibitors were ranked according to their clinical efficacy: Remdesivir > Favipiravir-RTP > Oseltamivir. Docking results obtained from the second and third templates aligned with clinical observations. Furthermore, Abacavir demonstrated a predicted efficacy comparable to Favipiravir-RTP, while Ribavirin exhibited a predicted efficacy similar to that of Remdesivir. This research, focused on inhibitors of SARS-CoV-2 RNA-dependent RNA polymerase, establishes a framework for screening AI-generated drug templates based on clinical outcomes. Additionally, it develops a drug screening platform based on molecular docking binding energy, enabling the evaluation of novel or repurposed drugs and potentially accelerating the drug development process.

Development of a multiplex polymerase chain reaction assay for detection of hepatitis C virus,hepatitis B virus,and human immunodeficiency virus 1

BACKGROUND Hepatitis C virus(HCV),hepatitis B virus(HBV),and human immunodeficiency virus 1(HIV-1)are the most epidemic blood-borne viruses,posing threats to human health and causing economic losses to nations for combating the infection transmission.The diagnostic methodologies that depend on the detection of viral nucleic acids are much more expensive,but they are more accurate than sero-logical testing.AIM To develop a rapid,cost-effective,and accurate diagnostic multiplex polymerase chain reaction(PCR)assay for simultaneous detection of HCV,HBV,and HIV-1.METHODS The design of the proposed PCR assay targets the amplification of a short conserved region featured with a distinguishable melting profile and electro-phoretic molecular weight inside each viral genome.Therefore,this diagnostic method will be appropriate for application in both conventional(combined with electrophoresis)and real-time PCR facilities.Confirmatory in silico investigations were conducted to prove the capability of the approached PCR assay to detect variants of each virus.Then,Egyptian isolates of each virus were subjected to the wet lab examination using the given diagnostic assay.RESULTS The in silico investigations confirmed that the PCR primers can match many viral variants in a multiplex PCR assay.The wet lab experiment proved the efficiency of the assay in distinguishing each viral type through high-resolution melting analysis.Compared to related published assays,the proposed assay in the current study is more sensitive and competitive with many expensive PCR assays.CONCLUSION This study provides a simple,cost-effective,and sensitive diagnostic PCR assay facilitating the detection of the most epidemic blood-borne viruses;this makes the proposed assay promising to be substitutive for the mistakable and cheap serological-based assays.

Low testing rates and high BRCA prevalence: Poly (ADP-ribose) polymerase inhibitor use in Middle East BRCA/homologous recombination deficiency-positive cancer patients

BACKGROUND Poly(ADP-ribose)polymerase inhibitors(PARPis)are approved as first-line therapies for breast cancer gene(BRCA)-positive,human epidermal growth factor receptor 2-negative locally advanced or metastatic breast cancer.They are also effective for new and recurrent ovarian cancers that are BRCA-or homologous recombination deficiency(HRD)-positive.However,data on these mutations and PARPi use in the Middle East are limited.AIM To assess BRCA/HRD prevalence and PARPi use in patients in the Middle East with breast/ovarian cancer.METHODS This was a single-center retrospective study of 57 of 472 breast cancer patients tested for BRCA mutations,and 25 of 65 ovarian cancer patients tested for HRD.These adult patients participated in at least four visits to the oncology service at our center between August 2021 and May 2023.Data were summarized using descriptive statistics and compared using counts and percentages.Response to treatment was assessed using Response Evaluation Criteria in Solid Tumors criteria.RESULTS Among the 472 breast cancer patients,12.1%underwent BRCA testing,and 38.5%of 65 ovarian cancer patients received HRD testing.Pathogenic mutations were found in 25.6%of the tested patients:26.3%breast cancers had germline BRCA(gBRCA)mutations and 24.0%ovarian cancers showed HRD.Notably,40.0%of gBRCA-positive breast cancers and 66.0%of HRD-positive ovarian cancers were Middle Eastern and Asian patients,respectively.PARPi treatment was used in 5(33.3%)gBRCA-positive breast cancer patients as first-line therapy(n=1;7-months progression-free),for maintenance(n=2;>15-months progression-free),or at later stages due to compliance issues(n=2).Four patients(66.6%)with HRD-positive ovarian cancer received PARPi and all remained progression-free.CONCLUSION Lower testing rates but higher BRCA mutations in breast cancer were found.Ethnicity reflected United Arab Emirates demographics,with breast cancer in Middle Eastern and ovarian cancer in Asian patients.

The fidelity of DNA synthesis by eukaryotic replicative and translesion synthesis polymerases

In their seminal publication describing the structure of the DNA double helix , Watson and Crick wrote what may be one of the greatest understatements in the scientific literature, namely that ＂It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material.＂ Half a century later, we more fully appreciate what a huge challenge it is to replicate six billion nucleotides with the accuracy needed to stably maintain the human genome over many generations. This challenge is perhaps greater than was realized 50 years ago, because subsequent studies have revealed that the genome can be destabilized not only by environmental stresses that generate a large number and variety of potentially cytotoxic and mutagenic lesions in DNA but also by various sequence motifs of normal DNA that present challenges to replication. Towards a better understanding of the many determinants of genome stability, this chapter reviews the fidelity with which undamaged and damaged DNA is copied, with a focus on the eukaryotic B- and Y-family DNA polymerases, and considers how this fidelity is achieved.

Flexibility in the order of action and in the enzymology of the nuclease, polymerases, and ligase of vertebrate non-homologous DNA end joining： relevance to cancer, aging, and the immune system

Nonhomologous DNA end joining （NHEJ） is the primary pathway for repair of double-strand DNA breaks in human cells and in multicellular eukaryotes. The causes of double-strand breaks often fragment the DNA at the site of damage, resulting in the loss of information there. NHEJ does not restore the lost information and may resect additional nucleotides during the repair process. The ability to repair a wide range of overhang and damage configurations reflects the flexibility of the nuclease, polymerases, and ligase of NHEJ. The flexibility of the individual components also explains the large number of ways in which NHEJ can repair any given pair of DNA ends. The loss of information locally at sites of NHEJ repair may contribute to cancer and aging, but the action by NHEJ ensures that entire segments of chromosomes are not lost.

Small Amplicons Mutation Library for Vaccine Screening by Error-Prone Polymerase Chain Reaction

Library construction is a common method used to screen target genes in molecular biology.Most library constructions are not suitable for a small DNA library(<100 base pair(bp))and low RNA library output.To maximize the library’s complexity,error-prone polymerase chain reaction(PCR)was used to increase the base mutation rate.After introducing the DNA fragments into the competent cell,the library complexity could reach 109.Library mutation rate increased exponentially with the dilution and amplification of error-prone PCR.The error-prone PCR conditions were optimized including deoxyribonucleotide triphosphate(dNTP)concentration,Mn^(2+)concentration,Mg^(2+)concentration,PCR cycle number,and primer length.Then,a RNA library with high complexity can be obtained by in vitro transcription to meet most molecular biological screening requirements,and can also be used for mRNA vaccine screening.

Deoxyribonucleic Acid-Polymerase Chain Reaction Status of HIV Exposed Infants in a Sub Regional Prevention of Mother-to-Child Transmission of HIV Programme during the Period 2009-2020

Introduction: Transitioning to more efficacious Antiretrovirals for HIV infected pregnant women and infant prophylaxis has reduced Mother to child transmission of HIV significantly. This study aimed to determine HIV infection status in HIVexposed infants who had their first DNA polymerase chain reaction test in our molecular Laboratory. Subjects, Materials and Methods: Dried Blood Spots for HIV DNA results from 5 states between 2009 and 2020 were analyzed in the PCR laboratory of the Federal Teaching Hospital, Gombe. Results: Nine thousand eight hundred and twenty-three Human Immunodeficiency Virus Deoxyribonucleic acid polymerase Chain Reaction results were analysed;4937 (50.2%) were males. During the study period, there was an overall declining trend in the mother-to-child transmission rate from 3.8% in 2009 to 1.0% in 2020. 6120 (62.3%) of HIV + mothers received Highly active antiretroviral therapy HAART before pregnancy. 7845 (76.2%) of the infants received Nevirapine prophylaxis. Dried blood spot samples were collected from 4077 (41.5%) at 6 - 8 weeks. 8438 (85.9%) received cotrimoxazole. 9469 (96.4%) were ever breastfed. Of the 9823 HIV DNA PCR results, 255 (2.6%) were positive while 69/4077 (1.7%) and 109/2662 (4.1%) were positive for HIV DNA at 6 - 8 weeks and > 12 weeks respectively. (p = 0.001). 86/747 (11.5%) of infants whose HIV-positive mothers received no ARVS were HIV DNA positive. (p = 0.001). 106/884 (12.0%) of infants who had no Antiretroviral prophylaxis had positive HIV DNA results;7/413 (1.7%) with Zidovudine/Nevirapine prophylaxis had positive results. (p = 0.001). 246/9469 (2.6%) of infants that were ever breastfed were positive for HIV DNA;11/354 (3.0%) that never breastfed had positive HIV DNA. Conclusion: Lack of maternal/infant ARVs and prolonged breastfeeding increased the risk of infant HIV infection.

Locked nucleic acid real-time polymerase chain reaction method identifying two polymorphisms of hepatitis B virus genotype C2 infections,rt269L and rt269I

BACKGROUND The presence of two distinct hepatitis B virus(HBV)Pol RT polymorphisms,rt269L and rt269I,could contribute to the unique clinical or virological phenotype of HBV genotype C2.Therefore,a simple and sensitive method capable of identifying both types in chronic hepatitis B(CHB)patients infected with genotype C2 should be developed.AIM To develop a novel simple and sensitive locked nucleic acid(LNA)-real timepolymerase chain reaction(RT-PCR)method capable of identifying two rt269 types in CHB genotype C2 patients.METHODS We designed proper primer and probe sets for LNA-RT-PCR for the separation of rt269 types.Using synthesized DNAs of the wild type and variant forms,melting temperature analysis,detection sensitivity,and endpoint genotyping for LNA-RT-PCR were performed.The developed LNA-RT-PCR method was applied to a total of 94 CHB patients of genotype C2 for the identification of two rt269 polymorphisms,and these results were compared with those obtained by a direct sequencing protocol.RESULTS The LNA-RT-PCR method could identify two rt269L and rt269I polymorphisms of three genotypes,two rt269L types[‘L1’(WT)and‘L2’]and one rt269I type(‘I’)in single(63 samples,72.4%)or mixed forms(24 samples,27.6%)in 87(92.6%sensitivity)of 94 samples from Korean CHB patients.When the results were compared with those obtained by the direct sequencing protocol,the LNA-RT-PCR method showed the same results in all but one of 87 positive detected samples(98.9%specificity).CONCLUSION The newly developed LNA-RT-PCR method could identify two rt269 polymorphisms,rt269L and rt269I,in CHB patients with genotype C2 infections.This method could be effectively used for the understanding of disease progression in genotype C2 endemic areas.

Confusing finding of quantitative fluorescent polymerase chain reaction analysis in invasive prenatal genetic diagnosis:A case report

BACKGROUND Quantitative fluorescent polymerase chain reaction(QF-PCR)is a rapid prenatal diagnostic method for abnormalities on chromosomes 21,18,and 13 and sex chromosomal aneuploidy.However,the value of QF-PCR in diagnosing chromosomal structural abnormalities is limited.In this article,we report a confusing QF-PCR finding in a pregnant woman who underwent amniocentesis.CASE SUMMARY The short tandem repeat marker AMXY(Xp22.2/Yp11.2)located on the sex chromosome exhibited a trisomic biallelic pattern,indicating that the karyotype of the fetus might be 47,XYY.Chromosome analysis performed on cultured amniocytes showed a normal male karyotype of the fetus.Copy number variation sequencing confirmed a 500 kb duplication at Yp11.2-Yp11.2(chrY:6610001_7110000)and a 250 kb duplication at Yp11.2-Yp11.2(chrY:7110001_7360000).CONCLUSION In conclusion,the comprehensive application of different methods could achieve a higher detection rate and accuracy for the prenatal diagnosis of chromosomal disorders through chromosomal testing.

Establishment of a rapid detection method of Ureaplasma urealyticum based on recombinant polymerase amplification

Ureaplasma urealyticum(UU),is one of the most vital pathogens causing genitourinary tract infections of the body,and it can result in poor maternal and perinatal outcomes.The aim of this study was to establish a method to detect Ureaplasma urealyticum based on recombinant polymerase amplification(RPA)technique.Specific primers and probes were designed according to the 16sRNA gene sequence of Ureaplasma urealyticum.Six pathogens were detected for real-time fluorescence RPA specificity verification,including Mycoplasma hominis(MH),Chlamydia trachomatis(CT),Neisseria gonorrhoeae(NG),Staphylococcus aureus,Escherichia coli,and Lactobacillus vaginalis.The sensitivity of the method was performed by gradient dilution of the extracted template.A total of 60 clinical samples were detected by the established real-time fluorescence RPA.Detection of Ureaplasma urealyticum can be completed within 20 minutes at 39°C using established RPA method.The minimum detection limit of Ureaplasma urealyticum by real-time fluorescence RPA was 3 pg.The evaluation of 60 clinical samples proved that RPA method was feasible.A high specificity,sensitivity,simplicity and rapidity method for Ureaplasma urealyticum detection was successfully established based on the real-time fluorescence RPA method.

4种植物源性成分多重real-time PCR检测方法的建立及其在食用淀粉中的应用

建立一种可同时快速检测红薯、木薯、马铃薯、玉米源性成分的多重实时聚合酶链式反应(real-time polymerase chain reaction,real-time PCR)方法。分别以红薯g3pdh基因、木薯g3pdh基因、马铃薯UGPase基因、玉米zSSIIb基因为靶基因设计特异性引物和TaqMan探针,以18S rRNA基因为内参基因,建立多重real-time PCR方法,开展方法学验证,并对不同掺入比例模拟样品和实际淀粉样品进行检测。结果显示,该方法具有高通量、特异性强、灵敏度高等优点。与15种非目标源性均无交叉反应;对目标DNA的检测灵敏度可达到3×10^(-3) ng/μL,且具有良好的线性关系和扩增效率;对淀粉样品的检出限可达0.1%,对50份实际样品进行检测,结果与参比方法一致,说明建立的多重real-time PCR法可用于食用淀粉种类掺假鉴别检测。

快速检测十足目虹彩病毒1 RPA-LFD方法的建立及初步应用

为建立一种高效、快速、简便的十足目虹彩病毒1(DIV1)检测方法,本研究以DIV1 ATPase基因为检测靶标,设计特异性引物和探针,采用方阵法优化反应温度和时间,结果显示,重组酶聚合酶扩增技术(RPA)最优反应温度为37℃,时间为15 min,结果观察时间为5 min,检测过程总时长为20 min,初步建立了DIV1的重组酶聚合酶扩增技术结合侧向流试纸条方法(RPA-LFD)。提取其他7种常见虾类病原基因组与DIV1基因组,采用该方法检测,分析其特异性;构建重组质粒标准品p UC57-DIV1,10倍倍比稀释后采用该方法检测,分析其灵敏性;以3种不同浓度的重组质粒标准品为模板进行批间、批内重复性试验。结果显示,该方法能特异性检测DIV1,与虾类其他常见易感病原均无交叉反应;其对重组质粒标准品的检测限为1×10^(1)拷贝/μL;批内和批间重复性试验的检测结果均一致,重复性好。利用该方法与已发表的荧光定量PCR(qPCR)同时检测15份感染DIV1的罗氏沼虾样品及40份临床样品,结果显示,该方法的阳性检测率为69.09%(38/55),阴性率为30.91%(17/55),与q PCR检测结果一致,二者的阳性符合率、阴性符合率、总符合率均为100%。综上所述,本研究建立的RPA-LFD方法检测DIV1具有快速、简便、灵敏度高且特异性强的特点,且不需要精密昂贵的仪器设备,为基层实验室及现场检测提供了可行技术手段。

Taq DNA聚合酶的分子改造及其在探针法qPCR直扩体系中的应用

Taq DNA聚合酶作为实时荧光定量聚合酶链式反应(qPCR)技术的核心组分,其性能优劣直接影响qPCR技术的进一步发展。然而,野生型Taq DNA聚合酶的耐抑制剂性能差、延伸性能不足。为获得具有高性能的Taq DNA聚合酶,采用基因工程技术将双链DNA结合蛋白Sso7d或Sto7d融合在野生型Taq DNA聚合酶的N端或C端,构建了4个均可溶表达的改造体,再经过耐受性测试筛选较优的改造体,结果显示:改造体Taq-Sto的耐受性最高,其热稳定性不受影响,且在1 s/kbp的延伸条件下能成功扩增靶标,表明Taq-Sto具有增强的延伸性能,在TaqMan探针法qPCR体系中对腐殖酸、单宁酸、全血等抑制剂同样表现出良好的耐受性。EMSA实验发现:Taq-Sto对DNA模板的结合亲和力有所提高,有利于增强Taq-Sto对模板的竞争力;将Taq-Sto应用于非洲猪瘟病毒(ASFV)的TaqMan探针法qPCR检测,与商品化试剂相比,Taq-Sto具有更低的ASFV检出限,且在体积分数为2%~6%的猪粪便样本或猪肉样本中的检测灵敏度分别为100.0%和85.4%,说明Taq-Sto在直扩qPCR检测领域更具有优势。

3种不同标志物对人淋巴管道内皮细胞鉴定效果研究

目的了解3种不同标志物对人淋巴管道内皮细胞鉴定效果。方法培养人淋巴管道内皮细胞,分别采用细胞免疫组织化学法及普通聚合酶链式反应(PCR)法检测同源异型盒基因转录因子-1(Prox-1)、淋巴管内皮透明质酸受体-1(LYVE-1)和血管内皮生长因子受体3(VEGFR-3)蛋白及mRNA表达水平。结果人淋巴管道内皮细胞传代后细胞免疫化学可见PROX1、LYVE1表达,未见VEGFR-3表达;普通PCR可见PROX1、LYVE1和VEGFR-33种标志物mRNA均有表达,VEGFR-3 mRNA表达水平明显下降。结论Prox-1、LYVE-1和VEGFR-3可用于相适合的人淋巴管道内皮细胞鉴定,结合文献分析VEGFR-3表达强弱可动态变化。

复合探针实时荧光RT-PCR法检测小儿上呼吸道感染甲型流感病毒的价值

目的 分析小儿上呼吸道感染甲型流感病毒应用复合探针实时荧光反转录聚合酶链反应(RT-PCR)法检测的临床价值。方法选择2023年1月至2023年12月流感监测信息系统两家监测点上呼吸道感染甲型流感病毒感染的患儿80例监测标本进行回顾性分析,均开展复合探针实时荧光RT-PCR法检测,分析其诊断价值。结果 根据监测标本最终诊断结果显示,阳性标本68例、阴性标本12例。经复合探针实时荧光RT-PCR法检出67例,检出率为83.75%,敏感度为95.59%、特异度为83.33%、准确度为93.75%、阳性结果预测值为97.01%、阴性结果预测值为76.92%;批间批内变异系数均小于5%。结论 小儿上呼吸道感染甲型流感病毒应用复合探针实时荧光RT-PCR技术具有较高的敏感度、特异度及准确度,且检查结果快速,可为小儿上呼吸道感染甲型流感病变提供可靠的诊断,有利于制订合理的治疗方案。

等温扩增技术在水产品寄生虫检测中的应用研究进展

水产品中寄生虫可引起食源性疾病,已成为影响食品安全的重要因素之一。近年来,基于传统分子生物学发展而来的等温扩增技术以其恒温、高效、耗时短、不过度依赖设备和仪器等优点,逐渐应用于分子诊断和疾病检测。该文在介绍等温扩增技术原理与特点的基础上,综述了其在水产品中寄生虫检测方面的应用研究进展,提出存在问题与解决办法,并展望了等温扩增技术的应用前景,以期为快检技术在水产品质量安全控制技术中的研究开发提供理论参考。

饮食习惯与肥胖患儿性早熟的相关性分析

目的探讨饮食习惯与肥胖患儿性早熟的相关性分析。方法选取苏州市吴中人民医院2019年3月至2022年3月期间收治的72例性早熟肥胖患儿作为观察组,另选取同期体检的健康肥胖儿童71例作为常规组。采用实时-逆转录荧光定量聚合酶链反应(RT-qPCR)检测两组外周血miR-125b水平,分析患儿饮食习惯。通过比较两组肥胖儿童的外周血miR-125b、饮食习惯,采用Logistic回归分析法分析外周血miR-125b、饮食习惯与肥胖患儿性早熟的关系。结果观察组外周血miR-125b表达水平高于常规组,差异有统计学意义(P<0.05)。观察组饮食没规律、荤多素少、高添加剂食品占比均高于常规组,差异有统计学意义(P<0.05)。观察组女性患儿、不良饮食习惯占比高于常规组,且经多因素分析显示外周血miR-125b表达水平、女性、不良饮食习惯是肥胖患儿性早熟的独立危险因素,差异有统计学意义(P<0.05)。结论肥胖患儿性早熟外周血miR-125b表达水平高于健康肥胖儿童,不良饮食习惯高于健康肥胖儿童,外周血miR-125b表达水平偏高、不良饮食习惯偏低均为肥胖患儿性早熟的影响因素。

实时荧光定量PCR法对ICU患者痰液标本中鲍曼不动杆菌耐药基因的检测及其评价

目的研究实时荧光定量聚合酶链式反应(PCR)法在重症监护室(ICU)患者痰液标本中检测鲍曼不动杆菌耐药基因的效果。方法选择2021年3月至2022年12月南阳市中心医院纳入的68例ICU患者进入试验,分别收集其痰液标本,通过实时荧光定量PCR法测定标本内鲍曼不动杆菌耐药基因情况,统计鲍曼不动杆菌及耐碳青霉烯类鲍曼不动杆菌的检出率,并观察耐碳青霉烯类鲍曼不动杆菌的药敏试验结果,最后分析OXA-51基因检查结果和耐药基因OXA-23检查结果。结果68例ICU患者的痰液标本中,通过传统培养方式检出鲍曼不动杆菌33株,阳性检出率48.53%;耐碳青霉烯类鲍曼不动杆菌共检出23株,阳性检出率33.82%;基因检测OXA-51阳性显示鲍曼不动杆菌有37株,阳性检出率54.41%;OXA-23阳性显示耐碳青霉烯类鲍曼不动杆菌有25株,阳性检出率36.76%。针对碳青霉烯类药物产生耐药的鲍曼不动杆菌所占比例占75.76%。耐碳青霉烯类鲍曼不动杆菌对于大部分药物耐药,耐药性较低的药物分别有头孢哌酮舒巴坦、米诺环素、替加环素、黏菌素等。传统培养和耐药基因的阳性检出率相比,差异并无统计意义(P>0.05);经Kappa检验显示为0.879,证实两种方式的检查结果的一致性较好。传统培养和耐药基因的阳性检出率相比,差异并无统计意义(P>0.05);经Kappa检验显示为0.712,证实两种方式的检查结果的一致性一般。结论实时荧光定量PCR法的效果明显,可成为鲍曼不动杆菌耐药基因检测的主要方式。

紫草素(shikonin)抗奥密克戎毒株的实验研究及机制分析

目的探讨右旋体紫草素(shikonin)抗奥密克戎毒株的药理作用和对新型冠状病毒主蛋白酶的抑制活性。方法使用奥密克戎毒株BA.2.2转染的Vero细胞模型检测shikonin的抗病毒活性;利用体外主蛋白酶荧光偏振模型测试shikonin对于新型冠状病毒主蛋白酶的抑制活性,实验以奈玛特韦为阳性对照化合物。结果Vero细胞模型药理活性测试发现shikonin具有抑制奥密克戎毒株核酸复制的作用;而在体外荧光偏振模型活性测试实验中,shikonin在20、50μM药物浓度并未表现出对主蛋白酶的显著抑制活性。结论紫草素(shikonin)在细胞水平的实验中表现出抗奥密克戎毒株的药理活性,但其可能是主蛋白酶的非特异性抑制剂,抗病毒的作用机理极可能为抑制新型冠状病毒RNA聚合酶。