Rapid Detection of rpoB Gene Mutations in Rif-resistant M.tuberculosis Isolates by Oligonucleotide Microarray

Objective To detect the specific mutations in rpoB gene of Mycobacterium tuberculosis by oligonucleotide microarray. Methods Four wild-type and 8 mutant probes were used to detect rifampin resistant strains. Target DNA of M. tuberculosis was amplified by PCR, hybridized and scanned. Direct sequencing was performed to verify the results of oligonucleotide microarray Results Of the 102 rifampin-resistant strains 98 （96.1%） had mutations in the rpoB genes. Conclusion Oligonucleotide microarray with mutation-specific probes is a reliable and useful tool for the rapid and accurate diagnosis of rifampin resistance in M. tuberculosis isolates.

Detection and identification of intestinal pathogenic bacteria by hybridization to oligonucleotide microarrays

AIM： To detect the common intestinal pathogenic bacteria quickly and accurately.METHODS： A rapid （〈3 h） experimental procedure was set up based upon the gene chip technology, Target genes were amplified and hybridized by oligonucleotide microarrays.RESULTS： One hundred and seventy strains of bacteria in pure culture belonging to 11 genera were successfully discriminated under comparatively same conditions, and a series of specific hybridization maps corresponding to each kind of bacteria were obtained. When this method was applied to 26 divided cultures, 25 （96.2%） were identified.CONCLUSION： Salmonella sp., Escherichia coli, Shigella sp., Listeria monocytogenes, Vibrio parahaemolyticus, Staphylococcus aureus , Proteus sp., Bacillus cereus, Vibrio cholerae, Enterococcus faecalis, Yersinia enterocolitica, and Campylobacter jejuni can be detected and identified by our microarrays. The accuracy, range, and discrimination power of this assay can be continually improved by adding further oligonudeotides to the arrays without any significant increase of complexity or cost.

Identification of osteopontin as the most consistently over-expressed gene in intrahepatic cholangiocarcinoma: Detection by oligonucleotide microarray and real-time PCR analysis

AIM: To investigate the molecular pathways involved in human cholangiocarcinogenesis by gene expression profiling. METHODS: Oligonucleotide arrays (Affymetrix U133A) were used to establish a specific gene expression profile of intrahepatic CCC in comparison to corresponding non- malignant liver tissue. To validate the expression values of the most overexpressed genes, RT-PCR experiments were performed. RESULTS: Five hundred and fifty-two statistically differentially expressed genes/ESTs (221 probes significantly up-regulated, 331 probes down-regulated; P < 0.05; fold change > 2; ≥ 70%) were identified. Using these data and two-dimensional cluster analysis,a specific gene expression profile was obtained allowing fast and reproducible differentiation of CCC, which was confirmed by supervised neuronal network modelling. The most consistently overexpressed gene (median fold change 33.5, significantly overexpressed in 100%) encoded osteopontin. Furthermore, an association of various genes with the histopathological grading could be demonstrated. CONCLUSION: A highly specific gene expression profile for intrahepatic CCC was identified, allowing for its fast and reproducible discrimination against non- malignant liver tissue and other liver masses. The most overexpressed gene in intrahepatic CCC was the gene encoding osteopontin. These data may lead to a better understanding of human cholangiocarcinogenesis.

Genome-wide identification of gene expression in the epididymis of infertile rat induced by alpha-chlorohydrin using oligonucleotide microarray

Objective To establish a rat model of sterility associated with epididymis and epididymal gene expression profiles relation to fertility by alpha-chlorohydrin.Methods Rats were treated with 10 mg·kg-1·d-1.alpha-chlorohydrin for 10 consecutive days.Sperm maturation and other fertility parameters were analyzed.The sperm motility and morphology were evaluated by computer-assisted sperm analysis(CASA);sperm survival rate was assessed by SYBR-14 and propidium iodide(PI)fluorescent staining;the weights of testes,epididymides,prostates and seminal vesicles were determined by electronic balance;histological examination of above tissues were evaluated by HE staining;and serumal dihydrotestosterone(DHT)and testosterone(T)of rats were detected by enzyme-labeled immunoassay.Each male rat was paired with 2 female rats in proestrus.Female rats were examined the next morning for the presence of sperm in vaginal smears and underwent a cesarean section on day 12 of gestation.Finally the reproductive indices were calculated as follows:copulation index(number of sperm positive females /number of pairings),pregnancy index(number of pregnancies /number of sperm positive females),and fertility index(number of pregnancies /number of pairings).After that we used Affymetrix Rat 230 2.0 oligo-microarray to identify epididymal special genes associated with fertility.Finally,we validated some of these genes by Real-Time quantitative polymerase chain reaction.Results The motility of spermatozoa from the cauda epididymidis of treated rats showed a significant decrease in percentage of motile,progressively motile sperm,and sperm survival rate.At the same time,the morphology of cauda epididymal spermatozoa was also adversely affected by the treatment.In addition,the serumal androgen levels of treated animals weren't changed compared with the control group.Accordingly,matings with treated males resulted in no successful pregnancy.Then,we classified general functions of the down or up regulated epididymal genes by chlorhydrin with the GeneSpring gene ontology(GO)analysis,which are involved in macromolecular metabolism and transport,primary metabolism process,cell metabolism,biological process regulation,immunology regulation,ion combination,hydratase and oxidoreductase activity.Among all the different expressed genes,we analyzed and screened the down-regulated genes associated with glucose,lipid,protein and other energy metabolism,which are considered as the major ACH action targets.Simultaneously,the up-regulated genes by chlorhydrin were detected and their characters of negative regulated sperm maturation and fertility analyzed,which are apoptosis and immune-related genes and not reported before.Conclusions We established male infertile rat model with ACH(10 mg·kg-1·d-1,po,10 days)through evaluating changes of sperm motility and morphology,mating index,fertility index and pregnancy index.Simultaneously,the ACH didn't affect the major androgen(T and DHT)metabolism and sexual ability,which is considered as the best way for male contraception.Then we determined the down-regulated epididymal genes relation to substance metabolism,which can affect the epididymal sperm maturation and presumed the major antifertility targets by ACH.Further more,we found and analyzed the epididymal up-regulated genes associated with apoptosis and immune functions,which maybe the new possible sites of action by ACH and other male antifertility agents.

Fabrication of oligonucleotide microarray for the detection of Japanese encephalitis virus

A low-density oligonucleotide microarray was used for the detection of Japanese encephalitis virus (JEV) , combining with restriction display PCR labeling method. The hybridization targets were amplified from 6 plasmids containing several JEV gene fragments. Corresponding oligonucleotide probe spots were detected unambiguously. We claim that the oligonucleotide microarray technology is feasible and may have potential for clinical laboratory application.

A comparison of gene expression in mouse liver and kidney in obstructive cholestasis utilizing high-density oligonucleotide microarray technology

AIM： To assess the effects of obstructive cholestasis on a wider range of gene expression using microarray technology. METHODS： Male C57BI_/6J mice underwent common bile duct ligation （BDL） and were matched with pairfed sham-operated controls. After 7 d, the animals were sacrificed and total RNA was isolated from livers and kidneys. Equal amounts of RNA from each tissue were pooled for each group and hybridized to Affymetrix GeneChip^MG-U74Av2 containing a total of 12488 probe sets. Data analysis was performed using GeneSpring 6.0 software. Northern analysis and immunofluorescence were used for validation. RESULTS： In sham-operated and BDL mice, 44 and 50% of 12488 genes were expressed in livers, whereas 49 and 51% were expressed in kidneys, respectively. Seven days after BDL, 265 liver and 112 kidney genes with GeneOntology annotation were up-regulated and 113 liver and 36 kidney genes were down-regulated in comparison with sham-operated controls. Many genes were commonly regulated in both tissues and metabolism-related genes represented the largest functional group. CONCLUSION： Following BDL, microarray analysis reveals a broad range of gene alterations in both liver and kidney.

Expression profiling of gastric cancer samples by oligonucleotide microarray analysis reveals low degree of intra-tumor variability

AIM： Gene expression profiling provides an unique opportunity to gain insight into the development of different types of gastric cancer. Tumor sample heterogeneity is thought to decrease the sensitivity and tumor specificity of microarray analysis. Thus, microdissection and preamplification of RNA is frequently performed. However, this technique may also induce considerable changes to the expression profile. To assess the effect of gastric tumor heterogeneity on expression profiling results, we measured the variation in gene expression within the same gasbic cancer sample by performing a gene chip analysis with two RNA preparations extracted from the same tumor specimen. METHODS： Tumor samples from six intestinal T2 gastric tumors were dissected under liquid nitrogen and RNA was prepared from two separate tumor fragments. Each extraction was individually processed and hybridized to an Affymetrix U133A gene chip covering approximately 18 000 human gene transcripts. Expression profiles were analyzed using Microarray Suite 5.0 （Affymetrix） and GeneSpring 6.0 （Silicon Genetics）. RESULTS： All gastric cancers showed little variance in expression profiles between different regions of the same tumor sample. In this case, gene chips displayed mean pair wise correlation coefficients of 0.94±0.02 （mean±SD）, compared to values of 0.61±0.1 for different tumor samples. Expression of the variance between the two expression profiles as a percentage of “total change” （Affymetrix） revealed a remarkably low average value of 1.18±0.78 for comparing fragments of the same tumor sample. In contrast, comparison of fragments from different tumors revealed a percentage of 24.4±4.5. CONCLUSION： Our study indicates a low degree of expression profile variability within gastric tumor samples isolated from one patient. These data suggest that tumor tissue heterogeneity is not a dominant source of error for microarray analysis of larger tumor samples, making total RNA extraction an appropriate strategy for performing gene chip expression profiling of gastric cancer.

SELECTION AND THEIR ANTITUMOR ACTIVITY OF ANTISENSE OLIGONUCLEOTIDES TARGETING MESSENGER RNA OF VASCULAR ENDOTHELIAL GROWTH FACTOR RECEPTOR 2

Objective： To select the antisense oligonucleotides （asONs） which hybridize with the mRNA of vascular endothelial growth factor receptor2 （VEGFR2, also named as kinase insert domain-containing receptor：KDR） in an effective and specific way, and to investigate their antitumor activity in MCF-7 cells. Methods： The effective antisense oligonucleotides were chosen by computer prediction combined with oligonucleotide microarrays. The inhibition effect on MCF-7 cells proliferation was measured by MTT; and VEGFR2 expression was surveyed by Western-blotting and RT- PCR. Results： Using predicting secondary structure of VEGFR2 mRNA with RNA folding program, computer prediction designed 30 antisense oligonucleotide probes that were directed to local loose regions of RNA structure. In 30 probes, 4（4/30, 13.33%） antisense oligonucleotides showed strong hybridization intensities in oligonucleotide microarrays test and were selected. All these antisense oligonucleotides targeting 4 different sites of VEGFR2 mRNA lowered the level of VEGFR2 mRNA and protein present in MCF-7 cells. Proliferation of MCF-7 cells was reduced by 4 antisense oligonucleotides, respectively, in which asON1 was the most effective, with the inhibitory rates being 53.06% at 0.8 I.tmol/L. Conclusion： Combination of computer prediction with oligonucleotide microarrays is an effective way in selecting optimal antisense oligonucleotides. The antisense oligonucleotides showed good correlation between their antitumor activity and the hybridization intensities. The antisense oligonucleotides targeting VEGFR2 mRNA demonstrated prominent antitumor role in vitro.

Binding tendency with oligonucleotides and cell toxicity of cetyltrimethyl ammonium bromide-coated single-walled carbon nanotubes

Functionalized carbon nanotubes （CNTs） were made for the delivery of genes and drugs and CNT-based biosensors. The basis of CNTs is for binding with biomolecules in biomedical applications. The binding tendency with small interfering RNA oligonucleotides and cytotoxicity of cetyltrimethyl ammonium bromide （CTAB）-coated single-walled carbon nanotubes （SWNTs） were studied. The field emission scanning electron microscopy and transmission electron microscopy results show that a SWNT suspension in CTAB solution was well-dispersed and stable. CTAB is the cross-linker between SWNTs and oligonucleotides. The CTAB-coated SWNTs have less cytotoxicity to human umbilical vein endothelial cells than single SWNTs and the cytotoxicity of CTAB-coated SWNTs depended on the concentration of CTAB-coated SWNTs.

Genotype of ethanol metabolizing enzyme genes by oligonucleotide microarray in alcoholic liver disease in Chinese people

OBJECTIVE: To explore the relationship between genetic polymorphisms of the ethanol metabolizing enzymes and the occurrence of alcoholic liver disease (ALD). METHODS: Sixty-five healthy male controls and 165 alcoholisms (including 122 ALD patients and 43 male alcohol abusers without liver complications defined as alcohol-dependent) were analyzed by polymerase chain reaction and hybridized with oligonucleotide microarray to detect the polymorphisms of the ethanol metabolizing enzymes genes. RESULTS: The frequencies of alcohol dehydrogenase gene 2 * 1 ( ADH2 * 1 ) allele were shown as 37.69%, 46.51% and 59.02% in control, alcohol-dependent and ALD groups respectively; while those of ADH2 * 2 allele were shown as 62.31 %, 53.49% and 40.98% respectively. No ADH2 * 3 was detected in any of the subjects. The frequency of ADH2 * 1 was significantly higher in alcoholisms (ALD group and alcohol-dependent group) than in healthy controls ( P

超高速细胞分选平台结合cDNA microarray技术筛查宫颈癌细胞潜在分子标志物

目的:通过超高速细胞分选平台结合cDNA microarray技术,筛查宫颈癌细胞可能潜在的分子标志物。方法:采用MoFlo XDP型超高速细胞分选平台纯化细胞膜表面表达CD38和不表达CD38的宫颈癌细胞,利用RNAlater技术得到cDNA microarray实验所需RNA,然后进行基因芯片分析。结果:利用MoFlo XDP型超高速细胞分选平台可以获得纯度为99.0%以上的CD38阳性表达宫颈癌细胞。结论:cDNA microarray分析发现了RORA、PLIN4、AUTS2、IFITM1等宫颈癌细胞潜在分子标志物,为宫颈癌研究提供了新的技术方法。

Expression and Significance of Survivin mRNA in Lung Cancer of Different Progression Stages by FISH and Tissue Microarray Technology*

Objective： To investigate the expression of Survivin mRNA in lung cancer progression tissue microarray by FISH （fluorescence in situ hybridization） method and determine its role and significance in lung cancer genesis and progress. Methods： The expression of Survivin mRNA was detected by FISH method and tissue microarray technology. 89 cases of primary lung cancer, 12 cases of lymph node metastasis of lung cancer, 12 cases of precancerous lesion and 10 cases of normal lung tissue were examined. Results： 69.7% of primary lung cancer express Survivin mRNA; the positive ratio of primary lung cancer and precancerous lesion were both significantly higher than that of normal lung tissue （P〈0.05）; the expression of Survivin mRNA was related to the differentiation degree, lymph node metastasis and clinical stages （P〈0.05）. Conclusion： FISH has good sensitivity and stability. Tissue microarray technology has many advantages, such as high efficiency, high throughput, etc; it may have good prospect in pathology. Survivin mRNA was highly expressed in lung cancer and precancerous lesion; it was related to the progress and malignant behavior; it may play a promotion role in lung cancer genesis and progress and offer basis to early diagnosis, prognosis estimate and treatment.

Expression of COX-2 in Different Subtypes of Gastric Intestinal Metaplasia and Gastric Carcinoma by Tissue Microarray

Objective: To study the expression of cyclooxygenase-2 (COX-2) protein in different subtypes of intestinal metaplasia (IM) and gastric carcinoma, evaluate the possibility of COX-2 forecasting the risk of malignant potential of IM, and the relationship between COX-2 expression and gastric carcinogenesis. Methods: Forty cases of chronic atrophic gastritis (CAG) with IM, 40 cases of gastric carcinoma and corresponding paracancerous tissues were selected to construct a tissue microarray. High iron diamine/alcian blue (HID/AB) staining and Hematoxylin and Eosin (HE) staining was used to classify IM and gastric carcinoma, and the expression of COX-2 protein detected in different subtypes of IM and gastric cancer by using immunohistochemistry. Results: The positive expression rate of COX-2 was 45.65%, 59.38% and 77.27% in IM foci in CAG, IM foci in paracancerous tissues, and intestinal-type gastric carcinoma, respectively, significantly higher than in diffuse-type gastric cancer (16.67%)(P<0.05, 0.005 and 0.005, respectively), and the expression intensity of COX-2 protein showed a increased tendency gradually in the sequence of IM foci in CAG→IM foci in paracancerous tissues→intestinal-type gastric carcinoma (P<0.005). The positive expression rate of COX-2 protein in type Ⅲ IM was significantly higher than in type Ⅰ and type Ⅱ IM (P<0.005 and 0.05, respectively), and the expression intensity also showed a increased tendency gradually from type Ⅰ to type Ⅲ IM (P<0.005). Conclusion: The expression level of COX-2 was increased gradually along with the increase of the risk of malignancy of IM, and its expression level may be a useful index to forecast the risk of malignant potential of IM. COX-2 expression was associated with intestinal-type gastric carcinoma, but it might also have some role in the carcinogenesis of diffuse-type gastric carcinoma.

Identification of p63 expression in human lung cancer: analysis by complementary DNA and tissue microarray

Objective: To evaluate p63 expression at mRNA transcripts and protein levels in lung squamous cell cancer (SCC), adenocarcinoma, large cell lung cancer (LCLC) and small cell lung cancer (SCLC) and their matched metastatic tumors. The association between p63 expression and p63 locus at chromosomal 3q27 q29 was also investigated. Methods: p63 mRNA expression levels in a large series of lung cancers including SCC, adenocarcinoma, LCLC, SCLC and their matched metastatic tumors were analyzed by cDNA microarray technology. A tissue microarray from 150 primary lung cancer specimens was constructed and used for immunohistochemical detection of p63 protein expression. Chromosomal imbalances at the p63 locus in 70 primary lung cancers samples were studied by comparative genomic hybridization (CGH) technology. Results: mRNA levels were 10 fold in SCC compared to LCLC, SCLC, and adenocarcinoma. Interestingly, the mRNA expression of p63 in metastatic carcinomas was significantly higher than that in their matched primary tumors ( P <0 001). Immunohistochemistry demonstrated that p63 expression was 94.64% in SCC but only 1 79% in lung adenocarcinoma and 2 of 4 LCLC were positive staining. All the results in of SCLC were negative. There was a statistically significant difference for p63 positivity between pT1 tumors and those of higher stage ( P =0 035). The CGH results indicated that p63 locus at chromosomal 3q27 q29 was overrepresented in SCC. p63 immunopositivity correlated significantly with pronounced gains of the p63 locus at chromosomal 3q27 q29 (P=0.0001), indicating that strong expression of p63 in lung SCC correlated with increased gene amplification. Conclusion: p63 might play an important role not only in squamous differentiation of lung cancer but also in tumor development and progression.

ROLE OF ANTISENSE AND DECOY OLIGONUCLEOTIDE OF NF-κB IN VESSEL STENOSIS AND NEOINTIMA FORMATION IN BALLOON-INJURED RAT ARTERY

Objective To examine antisense and decoy oligonucleotides of nuclear factor kappa B in vivo effects on intima proliferation and balloon-injured monocytes chemotactic protein-1 （ MCP-1 ） and extraceUular signal regulated kinase-2 （ERK2） κexpression in the carotid artery of rats. Methods Sprague-Dawley rats underwent balloon-dilation injury of the left carotid artery. Rats are divided into 7 groups （ n = 18 ） and each group includes6 time points （6 h, 1, 3, 5, 7, 14 d） （n =3）. Uninjured right carotid artery of the same rat was used as controls. Results In model group, sense group and scramble group, vessel intima area , media area and intima/media ratio increased after 5 d and reached the maximum after 7 d. The effect of antisense plus decoy group on intimal hyperplasia was more obvious than that of antisense group and decoy group alone. MCP-1 mRNA expression was increased expression continuously at 3, 5 and 7 d and decreased at 14 d. Compared with model group, sense group and scramble group, antisense group, decoy group and antisense plus decoy group had lowered MCP-1 mRNA expression in each time point （ P 〈 0. 05 ）. NF-KB p65 was dispersed positive stain 6 h after injury and increased after 1 d and peaked at 7 d, but the protein expression was weak at 14 d. ERK2 protein synthesis increased at I d and reached the peak at 7 d, while protein expression after 14 d was similar to that at 7 d. Treatment of antisense group, decoy group and antisense plus decoy group inhibited protein synthesis more significantly than those of model group, sense group and scramble group（ P 〈 0. 05）. Conclusion NF-KB modulates genes expression and protein synthesis of MCP-1 and ERK2. Celluar proliferation in vessel wall was dynamically changed after balloon angioplasty injury. Antisense and decoy oligonucleotide of NF-KB by local lipofectaraine transfer inhibit NF-KB activating gene modulation and neointimal hyperplasia.

α粒子诱发BEP2D细胞转化过程中肺癌相关基因表达的cDNA Microarray研究

目的：探讨辐射诱发人支气管上皮细胞(BEP2D)转化过程中肺癌相关基因的表达。方法：用Cartesian PixSys5500 cDNA Microarray点样仪将60个肺癌相关基因以微阵列形式点布于醛基化的玻璃片上。提取α离子辐射前BEP2D细胞（原代）和α粒子辐射后20代、35代细胞总RNA，经长片段反转录和线性扩增标记成荧光探针后与微阵列中cDNA进行杂交。结果：原代细胞中检测到40个基因表达；20代检测到47个基因表达；35代检测到20个基因表达。所检测的基因中，抑癌基因的mRNA丰度在原代和20代后细胞中急剧下降；大多数癌基因的表达丰度在20代以后细胞中仅轻微下降；生长因子类基因大都在20代细胞表达。结论：在辐射诱发的人支气管上皮转化细胞中，抑癌基因的失活可能与细胞恶化有关；癌基因及生长因子类基因可能促进了细胞的转化。

Design and application of 60mer oligonucleotide microarray in SARS coronavirus detection

The 60mer oligonucleotide microarray was designed and applied to detecting of SARS (severe acute res-piratory syndrome) coronavirus. Thirty 60mer specific oligos were designed to cover the whole genome of the first submit-ted coronavirus strain, according to the sequence of TOR2 (GENEBANK Accession: AY274119). These primers were synthesized and printed into a microarray with 12×12 spots. RNAs were extracted from the throat swab and gargling fluid of SARS patients and reverse-transcripted into the double strand cDNAs. The cDNAs were prepared as re-stricted cDNA fragments by the restriction display (RD) technique and labeled by PCR with the Cy5-universal primer. The labeled samples were then applied to the oligo microar-ray for hybridization. The diagnostic capability of the mi-croarray was evaluated after the washing and scanning steps. The scanning result showed that samples of SARS patients were hybridized with multiple SARS probes on the microar-ray, and there is no signal on the negative and blank controls. These results indicate that the genome of SARS coronavirus can be detected in parallel by the 60mer oligonucleotide mi-croarray, which can improve the positive ratio of the diagno-sis. The oligo microarray can also be used for monitoring the behavior of the virus genes in different stages of the disease status.

Sequencing of PCR amplified HBV DNA pre-c and c regions in 2.2.15 cells and antiviral action by targeted antisense oligonucleotide directed against sequence

AIM To study the specific inhibition of HBV gene expression by liver-targeting antisense oligonucleotide (ASON) directed against pre-c and c regious in a sequence-specific manner.METHODS According to the result of direct sequencing of PCR amplified products, a 16-mer phosphorothioate analogue of the antisense oligonucleotide (PS-ASOn) directed against the HBV U5-like region was synthesized and then linked with one live-targeting ligand, the galactosylated poly-L-lysine. Their effect on the expression of HBV gene was observed using the 2.2.15 cells.RESULTS HBV DNA in the 2.2.15 cells was from HBV with surface antigen subtype ayw1 by sequencing so that antisense oligonucleotides could bind specifically to the target sequence through base piring. Under the same experimental conditions, the inhibitory rates of PS-ASON to HBsAg and HBeAg were 70% and 58% at a concentration of 10μmol/L, while by ligand-PS-ASON they were 96% and 82%, the amount of HBV DNA in cultured supernatant and cells was reduced significantly. An unrelated sequence oligonucleotide showed no effectiveness. All the oligonucleotides had no cytotoxicity.CONCLUSION Antisense oligonucleotides complexed by the liver-targeting ligand can be targeted to cells via asialoglycoprotein receptors, resulting in supecific inhibition of HBV gene expression and replication.

An Improved Barcoded Oligonucleotide Primers-based Next-generation Sequencing Approach for Direct Identification of Viral Pathogens in Clinical Specimens

Objective To provide a feasible and cost-effective next-generation sequencing （NGS） method for accurate identification of viral pathogens in clinical specimens, because enormous limitations impede the clinical use of common NGS, such as high cost, complicated procedures, tremendous data analysis, and high background noise in clinical samples. Methods Viruses from cell culture materials or clinical specimens were identified following an improved NGS procedure： reduction of background noise by sample preprocessing, viral enrichment by barcoded oligonucleotide （random hexamer or non-ribosomal hexanucleotide） primer-based amplification, fragmentation-free library construction and sequencing of one-tube mixtures, as well as rapid data analysis using an in-house pipeline. Results NGS data demonstrated that both barcoded primer sets were useful to simultaneously capture multiple viral pathogens in cell culture materials or clinical specimens and verified that hexanucleotide primers captured as many viral sequences as hexamers did. Moreover, direct testing of clinical specimens using this improved hexanucleotide primer-based NGS approach provided further detailed genotypes of enteroviruses causing hand, foot, and mouth disease （HFMD） and identified other potential viruses or differentiated misdiagnosis events. Conclusion The improved barcoded oligonucleotide primer-based NGS approach is simplified, time saving, cost effective, and appropriate for direct identification of viral pathogens in clinical practice.

Screening of Serum Biomarkers for Distinguishing between Latent and Active Tuberculosis Using Proteome Microarray

Objective To identify potential serum biomarkers for distinguishing between latent tuberculosis infection（LTBI） and active tuberculosis（TB）. Methods A proteome microarray containing 4,262 antigens was used for screening serum biomarkers of 40 serum samples from patients with LTBI and active TB at the systems level. The interaction network and functional classification of differentially expressed antigens were analyzed using STRING 10.0 and the TB database, respectively. Enzyme-linked immunosorbent assays（ELISA） were used to validate candidate antigens further using 279 samples. The diagnostic performances of candidate antigens were evaluated by receiver operating characteristic curve（ROC） analysis. Both antigen combination and logistic regression analysis were used to improve diagnostic ability. Results Microarray results showed that levels of 152 Mycobacterium tuberculosis（Mtb）-antigenspecific IgG were significantly higher in active TB patients than in LTBI patients（P 〈 0.05）, and these differentially expressed antigens showed stronger associations with each other and were involved in various biological processes. Eleven candidate antigens were further validated using ELISA and showed consistent results in microarray analysis. ROC analysis showed that antigens Rv2031 c, Rv1408, and Rv2421 c had higher areas under the curve（AUCs） of 0.8520, 0.8152, and 0.7970, respectively. In addition, both antigen combination and logistic regression analysis improved the diagnostic ability. Conclusion Several antigens have the potential to serve as serum biomarkers for discrimination between LTBI and active TB.