Correlation of RAS mutations and microsatellite instability with clinico-pathological features and prognosis of patients with stage Ⅲ colorectal cancer / 中国病理生理杂志

AIM:To investigate the status of RAS/BRAF mutations and microsatellite instability ( MSI ) and their associations with clinicopathological features and prognosis of the patients with stage Ⅲ colorectal cancer ( CRC ) . METHODS:The surgical patients with stage ⅢCRC (n=281) were followed up.The mutations of RAS/BRAF were ex-amined by PCR amplification-Sanger sequencing , and MSI status was detected using immunohistochemistry ( IHC) in their archival paraffin-embedded tissue specimens .The relationships of the status with the clinicopathological features and prog-nosis of the patients were statistically analyzed .RESULTS: Among 281 patients, the mutations of RAS/BRAF were ob-served in 136 cases (48.4%), including 116 cases (41.3%) of KRAS mutations.RAS/BRAF mutations were highly cor-related with the level of carcino-embryonic antigen (P<0.05).Moreover, 18 cases (6.4%) of MSI-high (MSI-H) pa-tients were determined by IHC, and MSI-H status was more common in N2b patients (P<0.05).Correlation study found that the mutation rate of BRAF was higher in MSI-H tumors than that in MSI-low ( MSI-L)/microsatellite stability ( MSS) counterparts (P<0.01), although no association between KRAS/NRAS mutations and the MSI status was observed .The prognosis in the patients with wild-type RAS/BRAF or MSI-H was better than the patients with any mutation or MSI-L/MSS (P<0.01).CONCLUSION:Mutant RAS/BRAF and MSI may serve as fairly good indicators for prognosis of the patients with stage Ⅲ CRC.

Correlation of RAS mutations and microsatellite instability with clinico-pathological features and prognosis of patients with stage Ⅲ colorectal cancer / 中国病理生理杂志

AIM:To investigate the status of RAS/BRAF mutations and microsatellite instability ( MSI ) and their associations with clinicopathological features and prognosis of the patients with stage Ⅲ colorectal cancer ( CRC ) . METHODS:The surgical patients with stage ⅢCRC (n=281) were followed up.The mutations of RAS/BRAF were ex-amined by PCR amplification-Sanger sequencing , and MSI status was detected using immunohistochemistry ( IHC) in their archival paraffin-embedded tissue specimens .The relationships of the status with the clinicopathological features and prog-nosis of the patients were statistically analyzed .RESULTS: Among 281 patients, the mutations of RAS/BRAF were ob-served in 136 cases (48.4%), including 116 cases (41.3%) of KRAS mutations.RAS/BRAF mutations were highly cor-related with the level of carcino-embryonic antigen (P<0.05).Moreover, 18 cases (6.4%) of MSI-high (MSI-H) pa-tients were determined by IHC, and MSI-H status was more common in N2b patients (P<0.05).Correlation study found that the mutation rate of BRAF was higher in MSI-H tumors than that in MSI-low ( MSI-L)/microsatellite stability ( MSS) counterparts (P<0.01), although no association between KRAS/NRAS mutations and the MSI status was observed .The prognosis in the patients with wild-type RAS/BRAF or MSI-H was better than the patients with any mutation or MSI-L/MSS (P<0.01).CONCLUSION:Mutant RAS/BRAF and MSI may serve as fairly good indicators for prognosis of the patients with stage Ⅲ CRC.

Preparation of Element-doped Fluorescent Carbon Dots and Their Applications in Biological Imaging / 分析化学

Carbon dots have drawn a lot of attentions for their potential usage in bioimaging on the basis of their good biocompatibility and excellent anti-photobleaching ability. However, the relative low fluorescence quantum yield and lockage of near infrared fluorescence emission restrict their applications in the fluorescence imaging analysis. With the improvement of fluorescent properties through different elements doping, more and more carbon dots are used in biological imaging. In this paper, the synthesis of element-doped carbon dots, the influence by different elements doping and the development of element-doped carbon dots in imaging analysis are summarized, and the future prospect are anticipated.

Time interval from the end of sperm processing to artificial intrauterine in semination with husband's sperm correlates to the rate of clinical pregnancy / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the influence of the time interval from the end of semen processing to artificial intrauterine in semination with husband's sperm (AIH-IUI) on the rate of clinical pregnancy.</p><p><b>METHODS</b>This study involved 191 AIH-IUI cycles with the same ovulation induction protocol. After Percoll density gradient centrifugation, we divided the sperm into four groups based on the incubation time: 0-19, 20-39, 40-59, and 60-80 min, and again into another four groups according to the total progressively motile sperm count (TPMC): (0-9), (10-20), (21-30), and > 30 x 10(6). We analyzed the correlation of the clinical pregnancy rate with the time interval from the end of sperm processing to AIH-IUI and with other influencing factors, such as maternal age, infertility duration, and semen quality.</p><p><b>RESULTS</b>The rate of clinical pregnancy was significantly higher in the 20-39 min group (18.3%) than in the 0-19, 40-59, and 60-80 min groups (12.7, 11.4 and 9.1%) (all P < 0.05). The (10-20) x 10(6) group achieved a remarkably higher pregnancy rate (16.7%) than the (0-9), (21-30), and > 30 x 10(6) groups (0, 11.4, and 8.3%) (all P < 0.05). Logistic multivariate analysis showed that the rate of clinical pregnancy was decreased with the increased age of the women (OR 0.89, 95% CI 0.83-0.94) but significantly elevated in the 20-39 min group (OR 2.11, 95% CI 1.34-3.13) and of (10-20) x 10(6) group (OR 2.06, 95% CI 1.32-3.46).</p><p><b>CONCLUSION</b>The time interval from the end of sperm processing to AIH-IUI is a most significant factor influencing the rate of clinical pregnancy of AIH-IUI.</p>

Multiplex PCR assay for dissemination and diversity of extended-spectrum beta-lactamase genes in Shigella isolates / 中华预防医学杂志

<p><b>OBJECTIVE</b>To develop a rapid and simple multiplex polymerase chain reaction (PCR) method which discriminates extended-spectrum beta-lactamases (ESBLs) genes in sporadic Shigella isolates from 1998 to 2007 in Hangzhou city, China.</p><p><b>METHODS</b>After ESBLs screening according to the Clinical and Laboratory Standards Institute (CLSI) method, CTX-M, TEM, SHV and OXA-1 encoding genes were detected by using a multiplex PCR method, and the results were verified by 8 single gene PCR amplification.</p><p><b>RESULTS</b>Seventeen isolates harbored ESBLs genes among 195 Shigella isolates (8.72%). Genes encoding CTX-M (17 strains), TEM (2 strains), OXA-1 (10 strains) and SHV (0 strains) were discriminated with multiplex PCR analysis, which coincided with eight single gene PCR analysis at 94.12%.</p><p><b>CONCLUSION</b>Multiplex PCR should be a suitable tool for initial rapid screening and discriminating ESBLs genes in Shigella isolates. With similar trend of national surveillance data, the proportion of sporadic Shigella isolates harbouring ESBLs genes might probably be on increase.</p>

Preparation of armored RNA containing M gene of influenza H3N2 / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To prepare the armored RNA containing M gene of influenza H3N2.</p><p><b>METHODS</b>The vector pAR-1 was constructed from expression vector pET30b in which the bacteriophage MS2 DNA fragment, containing the genes for maturase and coat protein and the pac site, was inserted. The M gene fragment of influenza A was inserted into the HindIII site downstream of the pac site on the pAR-1, which formed a new recombinant plasmid pAR-2. After the prokaryotic expression was carried out, armored RNA AR-2 containing M gene was obtained. AR-2 was purified, and then was quantified by real time RT-PCR. Moreover, the stability of AR-2 was checked.</p><p><b>RESULTS</b>AR-2 was expressed successfully. AR-2 remained stable under various storage environments. Approximately 8.9 x 10(11) copies of AR-2 particles can be purified from one milliliter of culture.</p><p><b>CONCLUSION</b>It showed that AR-2 was stable and RNase-resistant, which, as a virus surrogate, would be used as RT-PCR standards, controls and training or proficiency samples.</p>

Detection of severe acute respiratory syndrome probable patients' virus RNA in Hangzhou by using a two loci and a modified nested real-time reverse transcription polymerase chain reaction / 中华预防医学杂志

<p><b>OBJECTIVE</b>To detect the RNA of severe acute respiratory syndrome virus (SARS-CoV) by using reverse transcription polymerase chain reaction (RT-PCR) targeted for a two loci and a modified nested real-time RT-PCR as to improving the reliability and sensitivity of tests.</p><p><b>METHODS</b>A nested RT-PCR was used for detecting one fragment of SARS-CoV RNA in oropharyngeal swabs from 3 SARS probable patients, 4 SARS suspect patients and other 27 patients with fever in Hangzhou, and the nested RT-PCR product from one SARS probable patient was sequenced. Meanwhile in these 3 SARS probable patients, other three RT-PCR methods, including a hemi-nested RT-PCR targeted for another fragment of SARS-CoV RNA, a real-time RT-PCR and a modified nested real-time RT-PCR, were employed to detect SARS-CoV RNA.</p><p><b>RESULTS</b>Two positives were found in the 3 SARS probable patients, and none positive in 4 SARS suspect patients and other 27 patients with fever, using the nested RT-PCR. The sequence of the nested RT-PCR product from one SARS probable patient was identified with the counterpart of SARS-CoV genomes published in public database. The results of the hemi-nested RT-PCR, the real-time RT-PCR and the modified nested real-time RT-PCR in the 3 SARS patients were consistent with the one of the nested RT-PCR. During detecting specimen with low copies of RNA, a weak positive signal was produced after about 35 cycles in the real-time RT-PCR, but a strong positive signal was found only after 10 cycles in the modified nested real-time RT-PCR.</p><p><b>CONCLUSION</b>It might improve the reliability of test by employing RT-PCR targeted for two or more fragments in SARS-CoV genome. The modified nested real-time RT-PCR might have higher sensitivity than the routine real-time RT-PCR.</p>