荧光定量RT-PCR在流感病毒检测上的应用

目的　探讨实时荧光定量RT PCR检测方法在流行性感冒检测诊断上的意义。方法　收集集体暴发疑似流感、SARS患者的咽拭子标本 16起 2 0 7份和双份血清标本 10 4份 ,应用荧光定量RT PCR检测方法、MDCK细胞培养法和血凝抑制试验进行病原学和血清学检测。结果　 2 0 7份集体暴发疑似流感、SARS患者的咽拭子标本中用荧光定量RT PCR检测 ,阳性 79份。阳性率 38 16 % (79 2 0 7)。MDCK细胞培养 ,16起中有 13起共 14 5份咽拭子有 6 2份标本阳性。阳性率 2 9 95 % (6 2 2 0 7)。两者的阳性率差异有显著意义 (χ2 =8.6 4 ,P <0 0 0 5 )。有 9起 10 4份成功的采集了双份血清 ,经HI试验有 6 4份双份血清与H3N2亚型抗原产生血抑 4倍增长 ,阳性率 6 1 5 4 % (6 4 10 4 )。结论　荧光定量RT PCR方法检测流感病毒能够在 3～ 4h内得出结果、且操作方便、特异性强、灵敏度高。因此我们认为实时荧光定量RT PCR方法 ,可作为一种快速的流感病毒检测诊断方法。     

Localization of Apaf1 gene expression in the early development of the mouse by means of in situ reverse transcriptase-polymerase chain reaction.

Apoptosis is an essential ubiquitous process that controls the duration of the life span of cells, thus playing a crucial role in morphogenetic, histogenetic, and phylogenetic developmental processes. Apaf1 (apoptosis protease activating factor 1) is one of the central mediators of the intrinsic apoptotic pathway and a part of the apoptosome, which activates procaspase-3 and promotes cell death. Gene knockout of Apaf1 in mice leads to late embryonic lethality with malformations such as the persistence of interdigital webs and hyperplasia of brain and retina. Therefore, Apaf1 is generally believed to play a crucial role in developmental apoptosis and have a widespread expression. However, its pattern of expression in early development remains unknown. To specify whether Apaf1 indeed plays this key role, we investigated the pattern of gene expression for Apaf1 in mouse embryos on day 7, 9, and 12 of development. Our results show, that gene expression for Apaf1 first occurs within the embryo between day 7 and 9 of development, becoming more widespread toward day 12 and then includes structures, such as yolk sac, mesenchyme, cartilage, heart anlage, otic vesicle, peridermis, and anlagen of the spinal ganglia and vertebral bodies. Our results also show that gene expression for Apaf1 is not ubiquitous in early mouse development. This finding indicates that cell death processes are independent of or less dependent on Apaf1 during this time. Of interest, an active gene expression for Apaf1 is also present in organ anlagen such as heart or intestine, in which no obvious phenotype is seen after Apaf1 deletion. This finding suggests a possible role for Apaf1 in such anlagen as a putative alternative compensatory pathway, which could be switched on in the case of defects in the mediators that are normally involved in such organs.     

Mammaglobin expression in gynecologic malignancies and malignant effusions detected by nested reverse transcriptase-polymerase chain reaction

The detection of micrometastatic disease remains a challenge for the diagnosis and monitoring of malignant disease. RT-PCR for human mammaglobin (hMAM) was recently shown to provide a sensitive method for assessing circulating breast cancer cells in peripheral blood. This study was aimed at investigating hMAM expression in normal and malignant tissue from the female genital tract and the prostate as well as in malignant effusions derived from gynecologic malignancies. hMAM expression was analyzed with nested RT-PCR in 152 samples of normal (n = 73) and malignant epithelial tissues (n = 79) and in 33 specimens of various normal mesenchymal tissue types. We found hMAM expression was not restricted to the normal mammary gland and breast carcinoma but was also detectable in most specimens of benign and malignant epithelial tissue from the ovary (97% versus 95%), uterus (both 100%), and cervix (91% versus 90%). Notably, hMAM expression was also found in benign prostatic hyperplasia (45%) and in prostate cancer (55%). A much lower expression rate was found in various normal and benign mesenchymal tissues (12%). In keeping with our previous data, hMAM expression was absent in all control samples (n = 124) of peripheral blood and bone marrow from healthy volunteers and patients with hematologic malignancies. In pleural or peritoneal effusions (n = 42) from patients with carcinomas of the breast, endometrium, or ovary, hMAM positivity was noticed in the majority of cases (74%), whereas only 52% of the specimens were cytologically positive for tumor cells. In conclusion, hMAM expression assessed by nested RT-PCR is a sensitive molecular marker for detecting micrometastatic tumor spread into pleural effusions and ascites from patients with breast cancer and various other gynecologic neoplasms.     

Detection of Dobrava-Belgrade hantavirus using recombinant-nucleocapsid-based enzyme-linked immunosorbent assay and SYBR Green-based real-time reverse transcriptase-polymerase chain reaction

Dobrava (DOBV) hantaviruses belong to the genus Hantavirus, family Bunyaviridae, and are carried by yellow-necked and striped field mice. The goal of this study was to detect DOBV using serological and genetic methods in Apodemus rodents in Hungary and in northern Croatia. During the study period, a total of 125 Apodemus sp. (67 A. agrarius, 58 A. flavicollis) were tested for the presence of hantaviruses, and 21 rodents (17%) were positive by rRT-PCR and/or ELISA. We conclude that the prevalence of DOBV is much higher than previously anticipated. The simultaneous use of molecular and serological techniques provides a highly reliable way to detect hantavirus infections.     

Rapid differentiation of avian infectious bronchitis virus isolates by sample to residual ratio quantitation using real-time reverse transcriptase-polymerase chain reaction

A rapid diagnostic assay for differentiating avian infectious bronchitis virus (IBV) isolates was developed. The basis of the assay is the cleavage of target RNA by RNase H mediated by sequence-specific chimeric oligonucleotides followed by sample to residual ratio quantitation (SRRQ) using RRT-PCR. Four serotype-specific chimeric oligonucleotides were designed, one each for the Massachusetts, Connecticut, Arkansas, and Delaware/Georgia 98 serotypes, and tested for their ability to mediate specific cleavage of target RNA from known homologous and heterologous strains of IBV. Specific cleavage of target RNAs by each chimeric oligonucleotide was verified using agarose gel analysis and RRT-PCR. There were no non-specific cleavage products. Eight different IBV strains representing seven serotypes were tested and each chimeric oligonucleotide mediated cleavage of target RNA only from strains within the serotype that the chimeric was designed against. The SRRQ assay was evaluated on 15 samples without prior knowledge of their grouping and correctly identified the serotype of each sample. The assay is rapid; six samples can be tested in approximately 4 h. In addition, the primer set amplifies all IBV RNAs tested to date and provides a built in control for detecting IBV whether it is typeable or not.     

Detection and quantitation of infectious pancreatic necrosis virus by real-time reverse transcriptase-polymerase chain reaction using lethal and non-lethal tissue sampling

Infectious pancreatic necrosis virus (IPNV) is a bisegmented double-stranded RNA virus belonging to the family Birnaviridae, genus Aquabirnavirus, which is a major viral pathogen of salmonid fish. The virus infects wild and cultured salmonids, causing high mortality in juvenile trout and salmon. A highly sensitive and specific real-time RT-PCR assay using the fluorogenic dye SYBR((R)) Green I was developed for the detection and quantitation of IPNV in rainbow trout (Oncorhynchus mykiss). Rainbow trout were infected experimentally with IPNV in the laboratory by injection or immersion and then pectoral fin, spleen, and head kidney samples were collected for analysis. The corresponding cDNA was synthesized using DNase I-treated total RNA and then real-time RT-PCR was performed using primers based on the IPNV non-structural protein gene, designated as either NS or VP4. Rainbow trout beta-actin and elongation factor 1alpha (EF-1alpha) genes were used as internal controls. Using real-time RT-PCR, the virus was successfully detected in pectoral fin, spleen, and head kidney tissue samples. The dissociation curves for each amplicon showed a single melting peak at 83, 81.5, and 84 degrees C for IPNV NS, trout beta-actin, and EF-1alpha genes, respectively. The amplicon size and nucleotide sequence was used to confirm the specificity of the products. Using a dilution series of in vitro transcribed RNA, IPNV was reliably detected down to 10 RNA copies and had a dynamic range up to 10(7) RNA copies. A time course assay, using immersion challenged samples, revealed that the virus could be detected in pectoral fin, spleen, and head kidney as early as 24h post-challenge. The average viral load in all three tissues increased over time, reaching its highest level at 21 days post-challenge, which was followed by a slight decrease at 28 days post-challenge. IPNV load in pectoral fin tissue was comparable to the viral load in spleen and head kidney tissues, indicating that pectoral fin could be used for the detection and quantification of IPNV. The development of a non-lethal detection method will be useful for the detection of IPNV and potentially other viruses of finfish in farmed and wild fish.     

巢式RT-PCR检测甲肝疫苗的感染性滴度研究

目的 建立一种快速灵敏特异的检测甲肝疫苗滴度的巢式RT-PCR检测方法。方法 运用巢式RT-PCR法对甲肝疫苗病毒滴度进行检测，并与细胞培养ELISA检测法进行比较。结果 巢式RT-PCR灵敏度和特异性均与细胞培养ELISA检测法相似。结论 巢式RT-PCR是一种简便、快速、灵敏的甲肝病毒检测方法，用于疫苗的常规检测有较好前景。     

实时荧光定量PCR检测乳腺癌SOCS2基因表达

目的检测乳腺良恶性组织中细胞因子信号转导抑制因子（supressors of cytokine signaling,SOCS2）的mRNA表达及其临床病理意义。方法以18SrRNA为内j对照采用实时荧光定量PCR法,定量测定新鲜乳腺癌组织、癌旁组织和乳腺良性增生组织中。SOCS2 mRNA的表达并分析其与临床病理指标的关系。结果各组阳性率：乳腺癌35.00％（14／40）、癌旁乳腺组织100％（15／15）和乳腺良性增生组织81.25％（13／16）,其表达之间的差异具有统计学意义（P〈0．05）;乳腺癌组织的SOCS2表达水平与TNM分期和淋巴结转移呈明显的相关性（P〈0,05）。结论SOCS2在乳腺癌中的表达可能提示患者具有较好的预后。