Analysis of three cases with false positive PCR results of non tuberculosis mycobacterium.

Background: Real-time fluorescent quantitative PCR (RT-PCR) can effectively distinguish between Mycobacterium tuberculosis (MTB) and Non-tuberculosis mycobacterium (NTM), but when there are overlapping sequences between other pathogens (such as Nocardia otidiscaviarum, Mycobacterium parantracellulare, Mycolicibacterium fluoranthenivorans) and NTM, abnormal amplification curves may appear. Case presentation: The clinical manifestations of the three patients were fever and respiratory symptoms. Chest CT showed "multiple lung infections". The acid-fast bacilli were negative by microscopic examination. The results of RT-PCR detection of Mycobacterium tuberculosis DNA showed that they are all NTM, while the results of DNA microarray method showed that there were no non-Mycobacterium tuberculosis. Identified by MALDI-TOF mass spectrometry, they are Nocardia otidiscaviarum, Mycobacterium parantracellale, Mycolicibacterium fluoranthenivorans. We found that the sequences of the above three bacteria can be combined with the primers and probes used for NTM PCR detection, resulting in false positive. Conclusions: In the RT-PCR detection of mycobacteria, if there's abnormal amplification, and the mycobacterial species cannot be identified, the amplified products sequencing or MALDI- TOF mass spectrometry identification will help avoid the omission of rare pathogens.

Distribution characteristics of antibiotic resistance genes and microbial diversity in the inshore aquaculture area of Wenchang, Hainan, China.

The rapid development of marine aquaculture has led to the increased use and release of antibiotics into the marine environment, consequently contributing to the emergence of antibiotic resistance. Information on antibiotic resistance in nearshore marine aquaculture areas remains limited, and research on the microbial composition and potential hosts of antibiotic resistance genes (ARGs) in marine aquaculture areas is scarce. This study used SmartChip real-time fluorescent quantitative PCR and qPCR to quantitatively analyze 44 ARGs and 10 mobile genetic elements (MGEs) genes in 12 sampling points in the nearshore aquaculture area of Wenchang. High-throughput sequencing of 16S rRNA was used to study microbial diversity in the study area, to clarify the correlation between ARGs, MGEs, and microbial diversity, and to determine the possible sources and potential hosts of ARGs. The results showed that a total of 37 ARGs and 8 MGEs were detected in the study area. The detection rate of 9 ARGs (aac(6')-Ib(aka aacA4)-02, catA1, cmlA, cfr, sul1, sul2, sulA/folP-01, tetC, tetX) was 100 %. The absolute abundance of ARGs in the 12 sampling points ranged from 2.75 × 107 to 3.79 × 1010 copies·L-1, and the absolute abundance of MGEs was 1.30 × 105 to 2.54 × 107 copies·L-1, which was relatively high compared to other research areas. ARGs and MGEs were significantly correlated, indicating that MGEs play an important role as a mediator in the spread of ARGs. At the phylum level, Proteobacteria and Cyanobacteria were the dominant bacteria in the study area, with HIMB11 and unidentifiedChloroplast being the dominant levels, respectively. Network analysis of ARGs and microorganisms (genus level) revealed that Cognatishimia, Thalassobius, Aestuariicoccus, Thalassotalea, and Vibrio were significantly correlated with multiple ARGs and were the main potential hosts of ARGs in the nearshore waters of Wenchang.

Diagnostic Efficacy of Plasma-Based Real-Time PCR for Schistosomiasis Japonica in Mice before and after Treatment with Praziquantel.

The prevalence of schistosomiasis japonica in China is now characterized by a low epidemic rate and low-intensity infections. Some diagnostic methods with high sensitivity and specificity are urgently needed to better monitor this disease in the current situation. In this study, the detection efficacy of a real-time fluorescent quantitative PCR (qPCR) assay was assessed for schistosomiasis japonica in mice, and before and after treatment with praziquantel (PZQ). Our results showed that the sensitivity of the qPCR was 99.3% (152/153, 95% CI: 96.41-99.98%) and its specificity was 100% (77/77, 95% CI: 95.32-100%) in mice infected with different numbers of Schistosoma japonicum. After the oral administration of PZQ, mice infected with 10 cercariae or 40 cercariae were all Schistosoma japonicum-negative 6 weeks after treatment. However, the negativity rates on a soluble egg antigen (SEA)-based enzyme-linked immunosorbent assay (ELISA) were only 34.8% (8/23, 10 cercariae group) and 6.7% (1/15, 40 cercariae group) at the sixth week after PZQ treatment. These results demonstrated that the qPCR method had good sensitivity and specificity, and suggested that its sensitivity correlated with the infection intensity in mice. Moreover, this method had better potential utility for evaluating the treatment efficacy of PZQ in schistosome-infected mice than SEA-based ELISA.

[Establishment and evaluation of a method for extracting exogenous short DNA fragments of Schistosoma japonicum from urine samples].

OBJECTIVE: To establish the method for extracting exogenous short DNA fragments of Schistosoma japonicum from urine samples, and to evaluate the efficiency of this method for extraction from urine samples treated with various methods. METHODS: The S. japonicum SjG28 gene fragment was selected as a target sequence, and the 81 bp short DNA fragment was amplified on the target sequence using PCR assay. Following characterization using sequencing, the short DNA fragment was added into the urine samples as an exogenous short DNA fragment. Primers and probes were designed with SjG28 as a target gene, to establish the real-time fluorescent quantitative PCR (qPCR) assay. The sensitivity of this qPCR assay was evaluated with exogenous short DNA fragments that were diluted at a 1:10 dilution ratio as the DNA template, and the specificity of the qPCR assay was evaluated with the genomic DNA of S. mansoni, S. haematobium, Babesia, Ancyiostoma duodenaie, Cionorchis sinensis, and Paragonimus westermani as DNA templates. Exogenous short DNA fragments were added into artificial and healthy volunteers' urine samples, followed by pH adjustment, centrifugation and concentration, and the efficiency of extracting exogenous short DNA fragments from urine samples was compared with the QIAmp Viral RNA Mini Kit (Qiagen kit) and BIOG cfDNA easy kit (BIOG kit). RESULTS: An 81 bp small DNA fragment of S. japonicum was successfully prepared, and the lowest detection limit of the established qPCR assay was 100 copies/µL of the 81 bp small DNA fragment of S. japonicum. If the genomic DNA of S. japonicum, S. mansoni, S. haematobium, Babesia, A. duodenaie, C. sinensis, and P. westermani served as DNA templates, the qPCR assay only detected fluorescent signals with S. japonicum genomic DNA as the DNA template. If the pH values of artificial urine samples were adjusted to 5, 6, 7 and 8, the recovery rates were (49.12 ± 2.09)%, (84.52 ± 4.96)%, (89.38 ± 3.32)% and (87.82 ± 3.90)% for extracting the exogenous short DNA fragment of S. japonicum with the Qiagen kit, and were (2.30 ± 0.07)%, (8.11% ± 0.26)%, (13.35 ± 0.61)% and (20.82 ± 0.68)% with the BIOG kit, respectively (t = 38.702, 26.955, 39.042 and 29.571; all P values < 0.01). If the Qiagen kit was used for extracting the exogenous short DNA fragment from artificial urine samples, the lowest recovery rate was seen from urine samples with a pH value of 5 (all P values < 0.05), and there were no significant differences in the recovery rate from urine samples with pH values of 6, 7 and 8 (all P values > 0.05). Following centrifugation of artificial [(64.30 ± 1.00)% vs. (58.87 ± 0.26)%; t = 12.033, P < 0.05] and healthy volunteers' urine samples [(31 165 ± 1 017) copies/µL vs. (28 471 ± 818) copies/µL; t = 23.164, P < 0.05]. In addition, concentration of artificial urine samples with the 10 kDa Centrifugal Filter and concentration of healthy volunteers' urine samples with the 100 kDa Centrifugal Filter were both effective to increase the recovery of the Qiagen kit for extracting the exogenous short DNA fragment of S. japonicum (both P values < 0.01). CONCLUSIONS: A method for extracting exogenous short DNA fragments of S. japonicum from urine samples has been successfully established, and the Qiagen kit has a high extraction efficiency. Adjustment of urine pH to 6 to 8 and concentration of healthy volunteers' urine samples with the 100 kDa Centrifugal Filter are both effective to increase the efficiency of extracting exogenous short DNA fragments of S. japonicum.

Molecular quantification for quality control of Jinqian Baihuashe in Jinlong Capsule / 药学学报

The quality control of Chinese patent medicines containing animal-derived crude drugs is relatively difficult, because the effective constituents of most animal-derived crude drugs remain unknown. Even if there are relevant methods, they are usually qualitative, and quantitative indicators are either lacking or have poor specificity. This paper has proposed to use molecular quantitative technology to control the quality of Chinese patent medicines containing animal-derived crude drugs. In this study, a molecular quantitative method based on fluorescence quantitative PCR was established for the determination of Jinqian Baihua She in Jinlong Capsule. The method has good specificity, sensitivity, and repeatability. There is a good linear relationship between the content of DNA fragments and the CT (cycle threshold) value. The content of the Bungarus multicinctus-specific fragment in Jinlong Capsule is 24.1-46.6 IU·mg-1. It is suggested that the content of the specific fragment of Jinqian Baihua She should not be less than 19.3 IU·mg-1 as one of the quality control criteria of Jinlong Capsule. The study can provide a reference for the quality control of Chinese patent medicines containing animal-derived crude drugs.

Analysis of pathogenic characteristics of enteroaggregative Escherichia coli in children with diarrhea in Shanghai from 2019 to 2021 / 上海预防医学

ObjectiveTo understand the presence of virulence genes， molecular typing characteristics， and antibiotic sensitivity of enteroaggregative Escherichia coli （EAEC） in children with diarrhea in Shanghai， so as to provide a scientific basis for EAEC monitoring and standardized treatment of EAEC infection. MethodsEAEC strains isolated from children （≤5 years old） with diarrhea in six districts of Shanghai were collected as the study subjects. EAEC virulence genes were detected by real-time fluorescence quantitative PCR， molecular typing was performed by pulsed-field gel electrophoresis （PFGE）， and drug susceptibility tests were conducted using the microbroth dilution method. χ2 test and two independent samples t-test were used to compare the differences in virulence genes and antibiotic resistance between suburban and urban EAEC strains. ResultsFrom 2019 to 2021， the overall detection rates of gene aggR， pic and astA of 59 EAEC were 30.5%， 50.8%， and 57.6%， respectively. There was no significant difference in the detection rates of virulence genes between suburban and urban EAEC strains （P>0.05）. PFGE analysis revealed that only two EAEC strains belonged to the same PFGE pattern and were collected from the same hospital， and the overall PFGE patterns were polymorphic. EAEC showed susceptibility to imipenem and colistin E， and the resistance rates to sulfamethoxazole （SXT）， ampicillin （AMP）， nalidixic acid （NAL）， and tetracycline （93.1%， 79.3%， 63.8%， and 58.6%， respectively） were higher than 50.0%. The antibiotic resistance rates of cefazolin （CFZ）， cefotaxime （CTX）， and ciprofloxacin （CIP） were significantly different between EAEC strains from suburban and urban areas （P<0.05）. A total of 47 strains exhibited multi-drug resistance， with the most common resistance spectrum being AMP-SXT-NAL. There was no statistically significant difference in the number of multidrug-resistant EAEC strains between suburban and urban areas （P>0.05）. ConclusionThe EAEC virulence gene assemblages in children with diarrhea in the six districts of Shanghai are diverse， and the molecular typing patterns are relatively scattered， indicating possible cross-infection of homologous strains. Multi-drug resistance in EAEC strains is relatively common， and there is a statistically significant difference in the resistance rates of CFZ， CTX and CIP between urban and suburban EAEC strains. Attention should be given to standardizing the use of clinical antibiotics to effectively control the dissemination of multidrug-resistant EAEC strains.

Establishment and evaluation of a method for extracting exogenous short DNA fragments of Schistosoma japonicum from urine samples / 中国血吸虫病防治杂志

Objective To establish the method for extracting exogenous short DNA fragments of Schistosoma japonicum from urine samples, and to evaluate the efficiency of this method for extraction from urine samples treated with various methods. Methods The S. japonicum SjG28 gene fragment was selected as a target sequence, and the 81 bp short DNA fragment was amplified on the target sequence using PCR assay. Following characterization using sequencing, the short DNA fragment was added into the urine samples as an exogenous short DNA fragment. Primers and probes were designed with SjG28 as a target gene, to establish the real-time fluorescent quantitative PCR (qPCR) assay. The sensitivity of this qPCR assay was evaluated with exogenous short DNA fragments that were diluted at a 1:10 dilution ratio as the DNA template, and the specificity of the qPCR assay was evaluated with the genomic DNA of S. mansoni, S. haematobium, Babesia, Ancyiostoma duodenaie, Cionorchis sinensis, and Paragonimus westermani as DNA templates. Exogenous short DNA fragments were added into artificial and healthy volunteers’ urine samples, followed by pH adjustment, centrifugation and concentration, and the efficiency of extracting exogenous short DNA fragments from urine samples was compared with the QIAmp Viral RNA Mini Kit (Qiagen kit) and BIOG cfDNA easy kit (BIOG kit). Results An 81 bp small DNA fragment of S. japonicum was successfully prepared, and the lowest detection limit of the established qPCR assay was 100 copies/μL of the 81 bp small DNA fragment of S. japonicum. If the genomic DNA of S. japonicum, S. mansoni, S. haematobium, Babesia, A. duodenaie, C. sinensis, and P. westermani served as DNA templates, the qPCR assay only detected fluorescent signals with S. japonicum genomic DNA as the DNA template. If the pH values of artificial urine samples were adjusted to 5, 6, 7 and 8, the recovery rates were (49.12 ± 2.09)%, (84.52 ± 4.96)%, (89.38 ± 3.32)% and (87.82 ± 3.90)% for extracting the exogenous short DNA fragment of S. japonicum with the Qiagen kit, and were (2.30 ± 0.07)%, (8.11% ± 0.26)%, (13.35 ± 0.61)% and (20.82 ± 0.68)% with the BIOG kit, respectively (t = 38.702, 26.955, 39.042 and 29.571; all P values < 0.01). If the Qiagen kit was used for extracting the exogenous short DNA fragment from artificial urine samples, the lowest recovery rate was seen from urine samples with a pH value of 5 (all P values < 0.05), and there were no significant differences in the recovery rate from urine samples with pH values of 6, 7 and 8 (all P values > 0.05). Following centrifugation of artificial [(64.30 ± 1.00)% vs. (58.87 ± 0.26)%; t = 12.033, P < 0.05] and healthy volunteers’ urine samples [(31 165 ± 1 017) copies/μL vs. (28 471 ± 818) copies/μL; t = 23.164, P < 0.05]. In addition, concentration of artificial urine samples with the 10 kDa Centrifugal Filter and concentration of healthy volunteers’ urine samples with the 100 kDa Centrifugal Filter were both effective to increase the recovery of the Qiagen kit for extracting the exogenous short DNA fragment of S. japonicum (both P values < 0.01). Conclusions A method for extracting exogenous short DNA fragments of S. japonicum from urine samples has been successfully established, and the Qiagen kit has a high extraction efficiency. Adjustment of urine pH to 6 to 8 and concentration of healthy volunteers’ urine samples with the 100 kDa Centrifugal Filter are both effective to increase the efficiency of extracting exogenous short DNA fragments of S. japonicum.

A multiplex real-time fluorescence-based quantitative PCR assay for calf diarrhea viruses.

Introduction: Calf diarrhea is a significant condition that has a strong effect on the cattle industry, resulting in huge economic losses annually. Bovine torovirus (BToV), bovine enterovirus (BEV), bovine norovirus (BNoV), bovine coronavirus (BCoV), bovine rotavirus (BRV), and bovine viral diarrhea virus (BVDV) are key pathogens that have been implicated in calf diarrhea. Among these viruses, there remains limited research on BToV, BEV, and BNoV, with no available vaccines or drugs for their prevention and control. Although commercial vaccines exist for BCoV, BRV, and BVDV, the prevalence of these diseases remains high. Methods: To address this issue, we developed a multiplex real-time fluorescence quantitative PCR method for detecting BToV, BEV, BNoV, BCoV, BRV, and BVDV. This method can be used to effectively monitor the prevalence of these six viruses and serve as a reference for future prevention and control strategies. In this study, we specifically designed primers and probes for the BNoV Rdrp, BEV 5'UTR, BToV M, BCoV N, BRV NSP5, and BVDV 5'UTR genes. Results: This method was determined to be efficient, stable, and sensitive. The lowest detectable levels of plasmids for BNoV, BEV, BToV, BRV, BCoV, and BVDV were 1.91 copies/µL, 96.0 copies/µL, 12.8 copies/µL, 16.4 copies/µL, 18.2 copies/µL, and 65.3 copies/µL, respectively. Moreover, the coefficients of variation for all six detection methods were < 3%; they also exhibited a strong linear relationship (R2 ≥ 0.98), and an amplification efficiency of 90%-110%. A total of 295 fecal and anal swabs were collected from calves with diarrhea in Guangdong, China. The positive rates for BToV, BEV, BNoV, BCoV, BR, and BVDV were determined to be 0.34% (1/295), 6.10% (18/295), 0.68% (2/295), 1.36% (4/295), 10.85% (32/295), and 2.03% (6/295), respectively. Notably, BEV and BRV exhibited the highest prevalence. Discussion: Additionally, this study identified the occurrence of BToV and BNoV in Guangdong for the first time. In summary, this study successfully established an effective method for detecting several important bovine viruses; ultimately, this holds strong implications for the future development of the cattle industry.

Selection and validation of reference genes for quantitative real-time PCR in Cymbidium sinense.

Selection of reference genes (RGs) is important for the accurate analysis of real-time quantitative PCR (RT-qPCR) results. This study screened RGs of Cymbidium sinense for more accurate quantification of target genes. The two most stable RGs for all tissues were ACT and EF1α, those for vegetative organs were UBQ3 and ACT, while those for reproductive organs as well as organs in the full flowering stage were EF1α and ACT. The AGAMOUS (CsAG1) expression level was verified using EF1α, ACT, GAPDH, UBQ2 and UBQ3 as RG. The expression profile of CsAG1 was consistent when normalized with EF1α, ACT and UBQ3. The results have practical value for the expression of key genes during the development of C. sinense.

Application evaluation of a rapid fluorescence quantitative PCR method for the detection of SARS-CoV-2 / 中华微生物学和免疫学杂志

Objective:To establish and evaluate a rapid nucleic acid detection method for SARS-CoV-2 based on COYOTE ? Flash20 real-time fluorescent quantitative PCR instrument. Methods:A rapid reaction system was constructed by using specific primer and probe sets targeting ORF1ab and N gene of SARS-CoV-2, and the sensitivity and specificity of the system were verified. At the same time, 108 clinical samples of COVID-19 were used to evaluate the application of this method.Results:The detection method did not require nucleic acid extraction, and the manual operation time was only one minute. After the sample was sent to the system, the test could be completed in 30 minutes. The detection limit of this method was 4×10 2 copies/ml. It had no cross-reactivity with other human coronaviruses (including HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1, SARS-CoV and MERS-CoV) and other respiratory viruses. The evaluation of clinical sample application showed that the total coincidence rate with the conventional RT-qPCR which required nucleic acid extraction was 98.15%. Conclusions:Through the application evaluation of the rapid fluorescent quantitative PCR method of SARS-CoV-2, it was found that the method was simple, fast, specific and sensitive, and it was suitable for real-time and rapid detection needs in varieties of situations.

Molecular and Toxicity Analyses of White Granulated Sugar and Other Processing Products Derived From Transgenic Sugarcane.

This study aimed to prepare the sugar industry for the possible introduction of genetically modified (GM) sugarcane and derived retail sugar products and to address several potential public concerns regarding the characteristics and safety of these products. GM sugarcane lines with integrated Cry1Ab and EPSPS foreign genes were used for GM sugar production. Traditional PCR, real-time fluorescent quantitative PCR (RT-qPCR), and enzyme-linked immunosorbent assay (ELISA) were performed in analyzing leaves, stems, and other derived materials during sugar production, such as fibers, clarified juices, filter mud, syrups, molasses, and final GM sugar product. The toxicity of GM sugar was examined with a feeding bioassay using Helicoverpa armigera larvae. PCR and RT-qPCR results showed that the leaves, stems, fibers, juices, syrups, filter mud, molasses, and white granulated sugar from GM sugarcane can be distinguished from those derived from non-GM sugarcane. The RT-qPCR detection method using short amplified product primers was more accurate than the traditional PCR method. Molecular analysis results indicated that trace amounts of DNA residues remain in GM sugar, and thus it can be accurately characterized using molecular analysis methods. ELISA results showed that only the leaves, stems, fibers, and juices sampled from the GM sugarcane differed from those derived from the non-GM sugarcane, indicating that filter mud, syrup, molasses, and white sugar did not contain detectable Cry1Ab and EPSPS proteins. Toxicity analysis showed that the GM sugar was not toxic to the H. armigera larvae. The final results showed that the GM sugar had no active proteins despite containing trace amounts of DNA residues. This finding will help to pave the way for the commercialization of GM sugarcane and production of GM sugar.

Research progress in molecular biology related quantitative methods of MicroRNA.

MicroRNAs (miRNAs) are small RNAs of 18-25 nucleotides in length that are widely distributed in eukaryotes and are produced by DNA transcription. As regulators of post-transcriptional gene expression, it plays an important role in the physiological processes of cells. As some miRNAs in the body are abnormally expressed at different and earlier stages of diseases, this phenomenon suggests that accurate, sensitive and specifical detection of them can be helpful for early and differential diagnosis. To expound the technological progress of miRNA detection, we reviewed all the related articles in PubMed database published before May 6, 2019, with the following keywords: "miRNA", "real-time fluorescent quantitative PCR", "electrochemical detection", "next-generation sequencing", "digital PCR technology". Original articles and reviews on the topics were selected. The present methods established for quantitative detection of miRNAs mainly relies on various probe design and labeling techniques, and the improvement of the sensitivity and specificity of detection is often through combination of microarray chips, real-time fluorescent quantitative PCR, high-throughput sequencing and other techniques. This paper combines the existing microRNA detection methods to provide a reference for researchers to choose the best detection method.

[In silico cloning, expression and bioinformatics analysis of StZnT11 in Solanum tuberosum].

Solanum tuberosum Zinc transporter 11 (StZnT11) is very important for maintaining zinc homeostasis in cells. The study on the expression of StZnT11 under abiotic stress and biotic stress laid a foundation for verifying the role of potato StZnT11 in the process of biotic stress of Ralstonia solanacearum species complex. According to the designated EST sequence, the homology of the original sequence was analyzed by using the Blast tool in NCBI, and a homologous object sequence with the highest similarity, coverage and e expectation value was selected. StZnT11 gene is obtained by Silico Cloning. The sequence and coding amino acid composition, physicochemical properties, molecular evolution, phosphorylation site and advanced structure of Solanum tuberosum StZnT11 gene were analyzed by bioinformatics method. The results showed that the cDNA gene is 1 300 bp in length, encoding a protein containing 348 amino acid residues, including 23 phosphorylation sites, one signal peptide and nine transmembrane regions, and is a hydrophobic protein located the plasma membrane. Through amino acid sequence alignment, StZnT11 protein has a high homology with zinc transporter from tobacco, tomato, pepper and other plants. The results of real-time fluorescence quantitative polymerase chain reaction showed that, StZnT11 is up-regulated by different concentrations of exogenous plant hormone abscisic acid (ABA). Tissue localization showed that StZnT11 was mainly expressed in specific tissues (phloem and leaf vascular bundles of stem vascular system). These results provide a theoretical basis for further experimental cloning and functional verification of the gene.

Analysis of differential expression profile of miRNA in peripheral blood of patients with lung cancer.

PURPOSE: To identify potential molecular targets for lung cancer intervention and diagnosis, we analyzed the differential miRNA expression of peripheral blood between lung cancer patients and healthy controls. METHODS: Three pairs of cases' and controls' peripheral blood samples were evaluated for miRNA expression by microarray. 12 miRNAs were selected for RT-PCR validation and target genes prediction. In addition, 4 miRNAs were selected for future validation by RT-PCR in a large sample of 145 cases and 55 frequency-matched healthy controls. RESULTS: A total of 338 differentially expressed miRNAs were screened and identified by microarray. According to the fold changes, the top ten upregulated miRNAs were hsa-miR-124-3p, hsa-miR-379-5p, hsa-miR-3655, hsa-miR-450b-5p, hsa-miR-29a-5p, hsa-miR-200a-3p, hsa-miR-542-3p, hsa-miR-138-5p, hsa-miR-219a-2-3p, and hsa-miR-4701-3p, and the top ten downregulated miRNAs were hsa-miR-34c-5p, hsa-miR-135a-5p, hsa-miR-132-3p, hsa-miR-3178, hsa-miR-4449, hsa-miR-4999-3p, hsa-miR-1246, hsa-miR-4424, hsa-miR-1252-5p, and hsa-miR-24-2-5p. RT-PCR verification of the 12 miRNAs revealed that 5 of 8 upregulated miRNAs, 2 of 4 downregulated miRNAs showed a significant difference between the cases and controls (P < .05). A large number of target genes and their functional set showed overlapping among the 453 predicted target genes of the 12 miRNAs (P < .01). RT-PCR in the large sample confirmed the significant differential expression level of hsa-miR-29a-5p, hsa-miR-135a-5p, hsa-miR-542-3p, and hsa-miR-4491 between cases and controls (P < .05), and three of these microRNA, except hsa-miR-29a-5p, were significant after Bonferroni correction for adjustment of multiple comparisons. CONCLUSION: There was a significant difference in miRNAs expression in the peripheral blood between lung cancer patients and healthy controls, and 4 miRNAs were validated by a large-size sample.

[Identification and expression pattern analysis of a Moso Bamboo LTR retrotransposon].

To develop more active LTR retrotransposons in Phyllostachys edulis, a Ph. edulis LTR retrotransposon (Ph-LTR2) was identified, and the expression pattern of the transposon under stress was systematically analyzed. Ph-LTR2 transposon is 6 030 bp in length and belongs to the Reina subfamily in the Ty3-Gypsy family. With the similarity of 96.41% of both LTR sequences, the Ph-LTR2 transposon inserted the moso bamboo genome about 61.92 thousand years ago. There are 5 copies identified in the genome. The Ph-LTR2 transposon domain includes GAG (gag protein) protein domain, PR (Proteases) protein domain, RT (Reverse transcriptase) protein domain, RH (Ribonuclease H) protein domain, INT (Integrase) protein domain and CHR (Chromatin organization modifier) protein domain. The expression patterns of INT, RT and RH were detected by real-time quantitative PCR. The three domains were found to have specific expression patterns at different tissues of the bamboo. Under the conditions of low/high temperature, methylation inhibitors treatments, irradiation and high salt stress, transcription levels of the three domains of the Ph-LTR2 transposon increased with different degrees. Specifically, after treatment with low/high temperature and methylation inhibitors, the transcription level was up-regulated; after low dose radiation treatment and low concentration of salt solution treatment, the transcription level was also increased, but the expression level decreased with increasing dose of radiation and concentration of salt solution. These results indicate that the expression pattern of the Ph-LTR2 transposon responds to the changes of the external environment, but the exact mechanism is not yet known. The results of this study laid a certain theoretical foundation for the development of the genetic tool based on Ph-LTR2 transposons.

Establishment and verification of real-time fluorescent quantitative PCR detection system for ring virus 6 / 中华实验和临床病毒学杂志

Objective@#To establish a real-time quantitative PCR detection system for Torque teno virus (TTV) and verify the sensitivity and specificity of the detection system.@*Methods@#Primers and FAM-Eclipse probes were designed based on the TTV6 gene sequence registered in GenBank, and were to establish a real-time fluorescent quantitative PCR detecting way based on the FAM-Eclipse probe, the standard curve was constructed and sensitivity and specificity were analyzed.@*Results@#A quantitative PCR method for the specific detection of TTV6 were established that the standard curve equation was y=-3.0921x + 28.36, and the amplification efficiency and R2 were 99.6% and 1.000, respectively. The sensitivity of TTV6 was 1.0×10 copies/μl, and there was no cross-reactivity with other viruses. There was 1 case positive for TTV6 out of 56 throat swab samples from the patients with clinical respiratory infection.@*Conclusions@#The real-time fluorescent quantitative PCR for detecting TTV6 established by FAM-Eclipse probe had the advantages of high sensitivity and specificity. It provides an effective way for detection and quantification of viral content of TTV6 in clinical specimens.

Pathogen spectrum of viral encephalitis in children living in Hebei province, China from May to December 2017 / 中华实验和临床病毒学杂志

Objective@#To investigate the pathogenic characteristics of viral encephalitis in children living in Hebei province.@*Methods@#We randomly collected cerebrospinal fluid specimens from a total of 399 children diagnosed with viral encephalitis in Hebei Children′s Hospital from May to December 2017. Real-time fluorescence quantitative PCR and Sanger sequencing were used to detect viral nucleic acids in cerebrospinal fluid by an automatic laboratory station. Statistical analysis was performed on the experimental data using SPSS 21.0 software and the clinical data were analyzed. Comparison of infection rates of EV encephalitis in different months, using line × column chi-square test. The MRI and EEG positive rates of different viral encephalitis and viral encephalitis patients not infected with the virus were analyzed by Fisher′s exact probability test. The positive rate of infection with different viruses and non-virus agents was analyzed by Fisher′s exact probability test.@*Results@#The result showed that 80 of 399 samples were positive, and the positive rate was 20.05%. It included 22 cases of enterovirus, 4 cases of influenza A virus, 3 cases of mumps virus, 2 cases of herpes simplex virus type 1, 1 case of herpes simplex virus type 2, 4 cases of EB virus, 7 cases of cytomegalovirus, 7 cases of herpes zoster virus, 8 cases of adenovirus, 14 cases of human herpesvirus type 6. Eight cases had combined viral infection. Eight cases had concurrent infections: 3 cases had enterovirus and herpesvirus type 6 concurrent infection, 1 case had enterovirus and Japanese encephalitis virus concurrent infection and 1 case had herpes simplex virus type 2 and adenovirus, 1 case had influenza A virus herpesvirus type 6, 1 case had mumps virus and herpesvirus type 6, 1 case had mumps virus and herpesvirus type 6, 1 case had herpes simplex virus type 1 and herpes zoster virus concurrent infections. Children with EV viral encephalitis in Hebei Province were highly prevalent in May and June (P=0.016). HHV6 virus encephalitis was more susceptible to infection than non-HHV6 virus (P=0.016); The rate of MRI positive findings in patients with different viral encephalitis was not statistically significant (P>0.05). The result of EEG of different viral encephalitis were P>0.05, which was not statistically significant.@*Conclusions@#EV was the most common pathogen of children with viral encephalitis in Hebei province. Encephalitis caused by influenza A virus cannot be ignored in clinical practice.

Identification and expression pattern analysis of a Moso Bamboo LTR retrotransposon / 生物工程学报

To develop more active LTR retrotransposons in Phyllostachys edulis, a Ph. edulis LTR retrotransposon (Ph-LTR2) was identified, and the expression pattern of the transposon under stress was systematically analyzed. Ph-LTR2 transposon is 6 030 bp in length and belongs to the Reina subfamily in the Ty3-Gypsy family. With the similarity of 96.41% of both LTR sequences, the Ph-LTR2 transposon inserted the moso bamboo genome about 61.92 thousand years ago. There are 5 copies identified in the genome. The Ph-LTR2 transposon domain includes GAG (gag protein) protein domain, PR (Proteases) protein domain, RT (Reverse transcriptase) protein domain, RH (Ribonuclease H) protein domain, INT (Integrase) protein domain and CHR (Chromatin organization modifier) protein domain. The expression patterns of INT, RT and RH were detected by real-time quantitative PCR. The three domains were found to have specific expression patterns at different tissues of the bamboo. Under the conditions of low/high temperature, methylation inhibitors treatments, irradiation and high salt stress, transcription levels of the three domains of the Ph-LTR2 transposon increased with different degrees. Specifically, after treatment with low/high temperature and methylation inhibitors, the transcription level was up-regulated; after low dose radiation treatment and low concentration of salt solution treatment, the transcription level was also increased, but the expression level decreased with increasing dose of radiation and concentration of salt solution. These results indicate that the expression pattern of the Ph-LTR2 transposon responds to the changes of the external environment, but the exact mechanism is not yet known. The results of this study laid a certain theoretical foundation for the development of the genetic tool based on Ph-LTR2 transposons.

Expression of FFAR4 protein and mRNA in pancreatic cancer and its clinical significance / 临床与实验病理学杂志

Purpose To detect the expression of FFAR4 protein and mRNA in pancreatic cancer and to discuss its role and significance in the progression of pancreatic cancer. Meth-ods Immunohistochemistry was used to detect the expression of FFAR4 protein in paraffin-embedded tissues from 62 cases of pathologically confirmed pancreatic cancer. The relationship be-tween the expression of FFAR4 and clinicopathological factors of pancreatic cancer was also studied. At the same time, the ex- pression of FFAR4 in 20 pairs of pancreatic cancer tissues and adjacent tissues were detected using Western bolt and real-time quantitative PCR (qRT-PCR). Results The results of immu-nohistochemistry showed that the expression rate of FFAR4 pro-tein in pancreatic carcinoma was 75. 8% (47/62) significantly higher than that in paratumor tissue 40. 3% (25/62), and the difference was statistically significant (P＜0. 05). The high ex-pression of FFAR4 was related to the degree of pancreatic cancer differentiation, TNM stage, and lymph node metastasis ( P ＜0. 05). Western blot and qRT-PCR showed that the expression of FFAR4 protein and its mRNA expression in pancreatic cancer tissues was significantly higher than matched paracancerous tis-sues. There was a statistically significant difference between the two groups ( P ＜0. 001 ). Conclusion The dysregulated ex-pression of FFAR4 may be closely related to the progression of pancreatic cancer. It is hopeful that FFAR4 may become a new marker for the prognosis of pancreatic cancer after surgery and a new target for the study of clinical therapeutic drugs.

Expression of c-IAPl protein and mRNA in gastric adenocarcinoma and its clinical significance / 临床与实验病理学杂志

Purpose To investigate the protein and mRNA expression of c-IAPl in gastric adenocarcinoma tissue and its clinical significance. Methods Immunohistochemistry technique, Western blot and realtime fluorescent quantitative PCR(qRT-PCR) were used to detect the protein and mRNA expression of c-IAPl in 50 cases of gastric adenocarcinoma tissues and40 cases of adjacent normal gastric mucosa tissues to analyze its role in the development and progression of gastric adenocarcinoma, the relationship between the protein and mRNA expression of c-IAPl and the clinicopathological features. Results The relative expression level of c-IAPl protein in gastric adenocarcinoma tissues was significantly higher than that in adjacent normal gastric mucosa tissues, the difference was statistically significant (P＜ 0.05 ). The mRNA expression of c-IAPl in gastric adenocarcinoma was significantly higher than normal gastric mucosa tissues, the difference was statistically significant (P＜0.05). The protein and mRNA expression of c-IAPl were correlated with the degree of differentiation of gastric adenocarcinoma tissues, TNM clinical stage, lymph node metastasis and infiltration depth, the difference was statistically significant (P＜0.05 ), while there was no correlation with gender and age, the difference was not statistically significant (P＞ 0.05). Conclusion The high protein and mRNA expression of c-IAPl in gastric adenocarcinoma tissues inhibit the apoptosis of gastric adenocarcinoma cells, which contribute to the development and progression of gastric carcinoma and it may provide a new theoretical basis for the clinical targeted therapy of gastric adenocarcinoma.