肺结核患者外周血腺苷脱氨酶活性与淋巴细胞的相关性研究

目的探讨肺结核患者外周血淋巴细胞内腺苷脱氨酶(ADA)活性和全血淋巴细胞绝对值的相关性。方法用全自动生化分析仪及全血细胞计数仪分别测定肺结核患者外周血的ADA活性和淋巴细胞绝对值、比值。结果肺结核活动期组与非活动期组外周血ADA活性均显著高于正常人组(P<0.05),肺结核活动期组与非活动期组患者外周血ADA活性与淋巴细胞绝对值的相关系数分别为0.191和0.154,P>0.05。结论肺结核患者淋巴细胞内ADA活性升高,淋巴细胞绝对值及比值减低,肺结核患者淋巴细胞内ADA活性升高与淋巴细胞绝对值无明显相关。     

吗啡对PC12细胞嘌呤核苷酸代谢相关酶基因表达的影响

目的：研究吗啡对神经细胞模型PC12嘌呤核苷酸补救合成酶与分解代谢关键酶基因表达的影响。方法：采用逆转录聚合酶链反应（RT-PCR）方法检测暴露于吗啡不同时间的PC12细胞次黄嘌呤-鸟嘌呤磷酸核糖转移酶（HGPRT）、腺苷激酶（AK）和腺苷脱氨酶（AD A）mRNA的表达水平。结果：与相应时段对照组相比，PC12细胞暴露于吗啡12及24 h时，HGPRT mRNA水平均明显增高(P<0.05)，作用48 h时HGPRT mRNA水平显著降低(P<0.05)，72 h后HGPRT mRNA水平再次升高(P<0.05)；吗啡处理的PC12细胞于12和24 h时，AK mRNA水平均明显降低(P<0.05)，作用48 h时AK mRNA水平升高(P<0.05)，72 h后AK mRNA水平恢复正常；ADA mRNA水平均表现为轻度降低，12 h差异有显著性(P<0.05)。结论：吗啡影响神经细胞嘌呤核 苷酸代谢，使细胞内腺苷酸及腺苷水平增高，这可能是吗啡依赖和耐受形成的机理之一 。     

婴儿双歧杆菌/胞嘧啶脱氨酶肿瘤靶向性基因治疗系统的构建(英文)

目的构建婴儿双歧杆菌/胞嘧啶脱氨酶靶向性基因治疗系统。方法 PCR 扩增 CD 基因,EcoR Ⅰ,BamH Ⅰ对 CD 基因和 pGEX-1LamdaT 质粒同时进行双酶切,获得4.9 kb、1.3 kh 两个 DNA 片段。T4 DNA 连接酶连接这两个片段构建重组的CD/pGEX-1LamdaT 质粒,然后用电穿孔法将重组质粒转染婴儿双歧杆菌。从阳性转染的婴儿双歧杆菌中提取重组质粒,双酶切后检测切取片段长度,采用 Sanger 双脱氧链终止法对提取的重组质粒中的插入片段进行测序。结果从阳性转染的婴儿双歧杆菌中获得了6.2 kb大小的重组质粒,该质粒经双酶切后,得到了4.9 kb 和1.3 kb 两个长度的片段,其长度分别与 pGEX-1LambdaT 及 CD 基因的长度相同。测序结果显示,提取的重组质粒中插入的基因片段全长及核苷酸序列与 CD 基因完全相同。结论外源性 CD 基因被准确插入 pGEX-1LambdaT 质粒并转入婴儿双歧杆菌中,婴儿双歧杆菌/胞嘧啶脱氨酶靶向性基因治疗系统被成功构建。     

Detection of biosynthetic gene and phytohormone production by endophytic actinobacteria associated with Solanum lycopersicum and their plant-growth-promoting effect

In the present study, fifteen endophytic actinobacterial isolates recovered from Solanum lycopersicum were studied for their antagonistic potential and plant-growth-promoting (PGP) traits. Among them, eight isolates showed significant antagonistic and PGP traits, identified by amplification of the 16S rRNA gene. Isolate number DBT204, identified as Streptomyces sp., showed multiple PGP traits tested in planta and improved a range of growth parameters in seedlings of chili (Capsicum annuum L.) and tomato (S. lycopersicum L.). Further, genes of indole acetic acid (iaaM) and 1-aminocyclopropane-1-carboxylate (ACC) deaminase (acdS) were successively amplified from five strains. Six antibiotics (trimethoprim, fluconazole, chloramphenicol, nalidixic acid, rifampicin and streptomycin) and two phytohormones [indole acetic acid (IAA) and kinetin (KI)] were detected and quantified in Streptomyces sp. strain DBT204 using UPLC-ESI-MS/MS. The study indicates the potential of these PGP strains for production of phytohormones and shows the presence of biosynthetic genes responsible for production of secondary metabolites. It is the first report showing production of phytohormones (IAA and KI) by endophytic actinobacteria having PGP and biosynthetic potential. We propose Streptomyces sp. strain DBT204 for inoculums production and development of biofertilizers for enhancing growth of chili and tomato seedlings.     

Brief overview of selected approaches in targeting pancreatic adenocarcinoma

Introduction: Pancreatic adenocarcinoma (PDAC) has the worst prognosis of any major malignancy, with 5-year survival painfully inadequate at under 5%. Investigators have struggled to target and exploit PDAC unique biology, failing to bring meaningful results from bench to bedside. Nonetheless, in recent years, several promising targets have emerged.

Areas covered: This review will discuss novel drug approaches in development for use in PDAC. The authors examine the continued efforts to target Kirsten rat sarcoma viral oncogene homolog (KRas), which have recently been successfully abated using novel small interfering RNA (siRNA) eluting devices. The authors also discuss other targets relevant to PDAC including those downstream of mutated KRas, such as MAPK kinase and phosphatidylinositol 3-kinase.

Expert opinion: Although studies into novel biomarkers and advanced imaging have highlighted the potential new avenues toward discovering localized tumors earlier, the current therapeutic options highlight the fact that PDAC is a highly metastatic and chemoresistant cancer that often must be fought with virulent, systemic therapies. Several newer approaches, including siRNA targeting of mutated KRas and enzymatic depletion of hyaluronan with PEGylated hyaluronidase are particularly exciting given their early stage results. Further research should help in elucidating their potential impact as therapeutic options.     

慢性低氧对大鼠血浆腺苷水平的影响

目的研究慢性低氧时大鼠血浆腺苷水平的变化及其机制。方法将42只雄性SD大鼠随机分成常氧组(对照组),低氧1 d、3 d、5 d、7 d、14 d、21 d组(H1、H3、H5、H7、H14、H21组),每组6只。分别于低氧第1天、第3天、第5天、第7天、第14天及第21天测定各组大鼠血浆腺苷水平、腺苷脱氨酶(ADA)活性以及血浆中5’-核苷酸酶(5’-NT)水平。应用SPSS 16.0软件进行统计学分析。结果低氧1 d后大鼠血浆腺苷水平开始升高,于第3天达到最高峰,与对照组比较差异有统计学意义(P<0.001);此后,随着低氧时间的延长,血浆腺苷水平逐渐下降,第14天及第21天与对照组比较差异均无统计学意义(Pa>0.05)。血浆5’-NT水平在低氧第3天增高最显著(P<0.001),在低氧3 d后逐渐下降,但仍高于对照组(P<0.001)。血浆ADA活性在慢性低氧第1天、第3天较对照组明显增高(Pa<0.001),随着低氧时间的延长,其活性稍下降,但仍明显高于对照组(P<0.001)。结论慢性低氧在早期可引起血浆腺苷水平增加,后期血浆腺苷水平逐渐降低,其变化与5’-NT水平和ADA活性有关。     

Measurement of deoxyinosine adduct: Can it be a reliable tool to assess oxidative or nitrosative DNA damage?

Adenosine deaminases (ADA) are key enzymes that deaminate adenosine (A) or deoxyadenosine (dA) and produce inosine or deoxyinosine (dI), respectively. While ADA only deaminates free dA, reactive nitrogen species (RNS) or reactive oxygen species (ROS) deaminate adenine base on the DNA and leave dI, which is a pre-mutagenic lesion. Therefore, dI adduct in the genomic DNA has been considered a biomarker of DNA damage caused by RNS or by ROS.     

112例老年性胸腔积液C反应蛋白和腺苷脱氨酶水平检测及其临床意义

目的探讨C反应蛋白(CRP)和腺苷脱氨酶(ADA)在老年性胸腔积液鉴别诊断中的价值。方法对112例老年性胸腔积液患者(其中结核性42例,癌性36例,炎性34例)的临床资料进行回顾性分析,并对各组的CRP和ADA水平进行比较。结果结核性胸腔积液CRP水平明显高于癌性胸腔积液,差异有统计学意义[(38.9±14.3)mg/Lvs(8.9±2.1)mg/L,P<0.01],而与炎性组差别无统计学意义[(38.9±14.3)mg/Lvs(34.7±12.7)mg/L,P>0.05];结核性胸腔积液ADA水平明显高于癌性胸腔积液与炎性胸腔积液,差异有统计学意义[(31.2±12.1)U/Lvs(14.1 8.2)U/L、(13.9±5.3)U/L,P<0.01]。结论联合检测CRP和ADA对老年结核性和癌性胸腔积液具有鉴别诊断价值。