OBJECTIVE:To observe the short-term efficacy and ADR of tenofovir disoproxil fumarate(TDF)in the treatment of multi-drug resistant chronic hepatitis B(CHB). METHODS:32 patients with multi-drug resistant CHB were analyzed retrospec-tively,and HBV drug-resistant genes were detected before treatment;there were a number of points to resistance;they were gave TDF orally. The recovery rate of serum alanine aminotransferase(ALT),HBV-DNA conversion rate,lactic acid and renal function were observed before and after treatment. RESULTS:The recovery rate of ALT reached 100% at 3 months,and the conversion rate of HBV-DNA reached 96.88%. The lactic acid levels and renal dysfunction was not found during treatment. CONCLUSIONS:TDF take effect quickly on multi-drug resistant CHB,and no obvious ADR is found.

Objective To investigate the prognostic factors for clinical relapse in chronic hepatitis B (CHB) patients with hepatitis B e antigen (HBeAg) seroconversion after drug withdrawal and to establish a prognostic model.Methods Totally 201 CHB patients with HBeAg seroconversion after the antiviral therapy were enrolled.The epidemiological variables including age, gender and family history of hepatitis B were collected.Liver function and hepatitis B virus (HBV) DNA level one week before initiation of antiviral therapy, hepatitis B surface antigen (HBsAg) level at the time of drug withdrawal and the duration of antiviral therapy after HBeAg seroconversion were analyzed.The clinical relapse after 48 weeks of drug withdrawal was followed up.The patients were divided into relapse group and non-relapse group according to clinical variables at 48 weeks after drug withdrawal.The counting data were analyzed by chi-square test and the measurement data were analyzed by t test.The Logistic regression model was used to determine the prognostic factors for clinical relapse.The receiver operating charactenstic (ROC) curve was constructed to assess the performance of the prediction model.Results The clinical relapse rate was 16.42% (33/201) after 48 weeks of drug withdrawal.By multivariate analysis, age, the duration of antiviral therapy after HBeAg seroconversion and HBsAg level at the time of drug withdrawal were independent predictors (χ2=14.546, t=3.202, t=3.286, respectively;all P<0.05).The regression model Logit (P)=1.220×age-0.040×the duration of antiviral therapy after HBeAg seroconversion +0.004×HBsAg level at the time of drug withdrawal-5.426.The sensitivity and specificity with the cut-off value of-0.860 were 73.10% and 90.40%, respectively.Conclusions Age, the duration of antiviral therapy after HBeAg seroconversion and HBsAg level at the time of drug withdrawal are independent predictors for clinical relapse 48 weeks after drug withdrawal in CHB patients with HBeAg seroconversion after antiviral therapy.

Objective To observe the clinical value of indocyanine green retention rate at 15 minutes (ICGR15) in the evaluation of hepatic functional reserve. Methods A total of 185 patients with liver disease, including 45 cases of liver failure, 90 cases of cirrhosis (child A, B and C, respectively), 20 cases of acute hepatitis, 30 cases of chronic hepatitis (mild, moderate). Expression levels of ICGR15 were compared between groups. Values of ICGR15, total bilirubin (TBIL), albumin (ALB), blood coagulation time (PT) were compared before treatment and one month after treatment in hepatic failure group. Levels of alanine aminotransferase (ALT), aspertate aminotransferase (AST), TBIL and ICGR15 were compared before treatment and 1 month after treatment in acute hepatitis group. Results Levels of ICGR15 (%) were 56.3±14.7, 28.9±9.6, 22.4±6.8 and 13.7±2.3 in liver failure group, liver cirrhosis group, acute hepatitis group and chronic hepatitis group, which showed a gradual downward trend (F=125.317, P<0.05). Among them, the levels of ICGR15 (%) were 17.3±5.4, 25.7±7.5 and 34.5±7.3 in Child A, B and C groups of liver cirrhosis group, which showed a gradual upward trend (P<0.05). After one month treatment, levels of TBIL, PT and ICGR15 were significantly lower than T helper 17 cells; intima-media thickness before the treatment in liver failure group. The levels of ALT, AST, TBIL and ICGR15 were significantly lower after treatment than those before treatment in acute hepatitis group (P<0.05). Conclusion ICGR15 can reflect hepatic reserved function, which is not affected by the application of albumin and fresh plasma, and makes up the deficiency of PT and ALB detection.

To identify the isolated suspicious strain of Campylobacter jejuni from the blood of bacteremia patient in Guizhou Province ,China ,conventional and molecular techniques (specific mPCR and NAP-mPCR) were used to identify suspi-cious bacteria strains .Results showed that Campylobacter jejuni suspicious colonies were cultured in bacteremia patient blood samples .The strain was identified as Campylobacter jejuni ssp . jejuni by conventional tests and was identified as Campy-lobacter jejuni by genus specific mPCR .Then the strain was classified as Campylobacter jejuni ssp . jejuni by subspecies NAP-mPCR .The strain was identified as Campylobacter jejuni ssp .jejuni isolated from the blood of bacteremia patient and Campylobacter jejuni can be identified subspecies by NAP-mPCR .

Eight patients with suspected cases of C .jejuni were etiologically diagnosed and analyzed in this study to pro-vide scientific basis for the confirmation of the cases of human campylobacteriosis in Guizhou Province ,China .Blood or feces of 8 suspected patients were employed to isolate bacteria strains .Conventional and multi-PCR techniques were applied to identify suspicious bacteria strains .The C .jejuni strains were analyzed by using Pulsed Field Gel Electrophoresis (PFGE) .Suspicious strains of C .jejuni were isolated from all the 8 suspected patients of campylobacteriosis and anticipated genes fragment were detected with multi-PCR .With the digestion of restriction enzyme SmaI ,the 8 C .jejuni strains were divided into 7 PFGE pat-terns with 7-10 DNA bands .Cluster analysis showed that the gross similarity of 8 strains of C . jejuni was more than 50% . The similarity of PFGE patterns between strain GZ201004 and GZ201005 from diarrhea patients was as high as 100% ,while the similarity of strain GZ201201 and GZ201007 was 66 .7% .Moreover ,C . jejuni were detected from all the suspected pa-tients of campylobacteriosis .PFGE results indicated that strains GZ201004 and GZ201005 were from the same source ,while all the 8 isolates showed PFGE polymorphism .

Objective To study the composition of variant and point mutations of Norovirus GⅡ.4 in Guiyang regions.Methods From June to November 2010,cases information and fecal specimens were collected from guard-hospitals in Guiyang regions,who had caught the acute-gastroenteritis.Noroviruses in specimens were detected by a real-time reverse transcription polymerase chain reaction(real-time RT-PCR),and then partial genotyped norovirus-positive clinical samples (in random) were cloned and sequenced in VP1 gene code.Furthermore,the gene sequences were compared with the published variants at home and abroad of norovirus(GⅡ.4),including the phylogenetic analyses of genomes and variation of amino acids within individual sites.Results Those 267 specimens were GⅡ-norovirus-positive(62.68％) in 426 clinical samples.There were nine GⅡ.4-norovirus-positive VP1 gene-sequences available,and two subtype-norovirus variants (GⅡ.4 2008a and G Ⅱ.4 2008b variant) were epidemic in 2010,Guizhou province.The homology between and in subgroups were 95.90％-96.72％ and 99.45％-100％.Two amino acids within individual sites were apt to mutate.Conclusion Norovirus GⅡ genotype were predominant in summer and fall acute gastroenteritis in 2010 for Guiyang regions,and the variants were diversity.

To study the characteristic of glycoprotein gene sequence of rabies virus in Guizhou Province in recent years and provide scientific basis for effective control and prevention of rabies,RT-PCR assay were used to detect human and dog brain tissues derived from different prefectures of Guizhou.The amplification products were sequenced and analyzed with bioinformatics software.The results showed that the full-length G gene sequences of 8 positive samples were obtained by RT-PCR amplification,sequencing and splicing.The homology of eight G gene sequences from Guizhou Province were between 87.4％ -99.9％ and 83.3.％- 100％ on nucleotide and deduced amino acid level,respectively,and the highest homology were found with the genotype 1 strains ( 86.5 ％- 87.0％ for nucleotide and 83.3 ％- 100 ％ for amino acid) among genotype 1- 7 representative strains.Besides,phylogenetic analysis based on the G gene indicated that the relationship of 8 strains derived from Guizhou were closest to genotype 1 Lyssavirus,and the strains of Guizhou were very close to the strains come from Hubei,Hunan,Anhui,Guangxi,Jiangsu provinces and Shanghai,except for GZ01 and GZ09.Moreover,GZ09 were evolutionarily closed to the strains come from Malaysia and Thailand,while the remaining sequences were closed to the strain of Indonesia.This study confirmed on the G gene level that rabies virus epidemic strains circulated in Guizhou Province in recent years belonged to rabies virus genotype 1 and the evolutionary relationship with reported strains come from different provinces of China and different countries were revealed in this study.It will provide scientific basis for effective control and prevention of human and animal rabies in Guizhou Province.

Objective To confirm the death of a child injured by a dog was due to rabies and to understand the molecular biologic features of rabies virus in Kaili,Guizhou province.Methods Brain tissue samples of patient and dog were collected to detect the rabies virus by direct immunofluorescence assay (DFA) and RT-nested PCR assay.Homology and phylogenetic tree were analyzed based on the whole nucleotide and deduced amino acid sequence of N gene of rabies virus followed by molecular epidemiological analysis.Results Both the human and dog brain tissue samples were confirmed positive by DFA and RT-nested PCR assay.The homology analysis of N gene sequences among GZH,GZD and other epidemic and vaccine rabies strains isolated from other provinces and other countries indicated that the detected samples shared the highest homology with the strain detected in Anlong prefecture in Guizhou in the year of 2006,and the homology between GZH and GZD was as high as 100％.Besides,among the vaccine strains,GZH and GZD showed the highest homology with strain CNT.Phylogenetic analysis indicated that the two samples were very close and belonged to genetype 1 lyssavirus,with the closest relationship between samples reported in Guizhou and Beijing.Conclusion It was confirmed on the viral molecular level that both the human and dog in Kaili were suffered from rabies,and the pathogens were genetype 1 lyssavirus.The prevalent strains in Kaili city was probably imported from other prefectures of Guizhou province,suggesting that prevention and control measures on rabies in Guizhou province should be strengthened.

Prediction of RNA secondary structures including pseudoknots is a difficult topic in RNA field. Current predicting methods usually have relatively low accuracy and high complexity. Considering that the stacking of adjacent base pairs is a common feature of RNA secondary structure, here we present a method for predicting pseudoknots based on covariance with stacking and minimum free energy. A new score scheme, which combined stacked covariance with free energy, was used to assess the evaluation of base pair in our method. Based on this score scheme, we utilized an iterative procedure to compute the optimized RNA secondary structure with minimum score approximately. In each interaction, helix of high covariance and low free energy was selected until the sequences didn't form helix, so two crossing helixes which were selected from different iterations could form a pseudoknot. We test our method on data sets of ClustalW alignments and structural alignments downloaded from RNA databases. Experimental results show that our method can correctly predict the major portion of pseudoknots. Our method has both higher average sensitivity and specificity than the reference algorithms, and performs much better for structural alignments than for ClustalW alignments. Finally, we discuss the influence on the performance by the factor of covariance weight, and conclude that the best performance is achieved when lambda1 : lambda2 = 5 : 1.
Algorithms ; Base Pairing ; Base Sequence ; Computational Biology ; methods ; Molecular Sequence Data ; Nucleic Acid Conformation ; RNA ; chemistry ; genetics ; Sequence Analysis, RNA

Objective To study the differences of glycoprotein gene (G gene) between rabies virus epidemic strains of Guizhou province in recent years and vaccine strains,and to provide scientific basis for the development of rabies vaccine and establishment of effective control and prevention measures.Methods RT-PCR assay was used to amplify the G gene of rabies positive brain tissues samples of human and dog derived from Guizhou province in recent years.The amplification products were sequenced and comparatively analyzed with that of vaccine strains by using bioinformatics software.Results Eight full-length G gene sequences were obtained by RT-PCR amplification,sequencing and splicing.The homogeny of G gene between 8 epidemic strains of Guizhou province and 9 vaccine strains were 82.0％-94.1％ and 87.6％-97.5％ on nucleotide and deduced amino acid level,respectively,and the highest homogeny were found with the human vaccine strain CTN (87.0％-94.1％ for nucleotide and 93.7.％-97.5％ for amino acid) among the 6 human rabies vaccine strains,while highest homogeny were found with strain Flury (83.9％-84.6％ for nucleotide and 91.1％-93.0％ for amino acid) among the three animal vaccine strains.Besides,among the 8 epidemic strains from Guizhou province,strain GZ09 collected in the year of 2005 was of the highest homogeny with human rabies vaccine strain CTN and animal rabies vaccine strain Flury,while strain GZ30 collected in the year of 2010 was of lowest homogeny with human rabies vaccine strain CTN and animal rabies vaccine strain Flury.Moreover,phylogenetic analysis based on the G gene indicated that the relationship of 8 epidemic strains derived from Guizhou,the 9 vaccine strains and genotype 1 Lyssavirus were clustered to a same branch.Vaccine strain CTN among the 9 vaccine strains was closest to the 8 epidemic strains,and the other 8 vaccine strains were relatively more distant from the epidemic strains of Guizhou province.In addition,phylogenetic analysis indicated that among the 8 epidemic strains from Guizhou province,strain GZ09 collectcd in the year of 2005 was of closest evolutionary relationship to CTN,while the other 7 epidemic strains were relatively more distant from CTN.Conclusion This study confirmed on the G gene level that rabies virus strains circulated in Guizhou province in recent years and the vaccine strains used in China belonged to rabies virus genotype 1,and the virus strains circulated in Guizhou province in recent years is of smallest difference with the human vaccine strain CTN and animal vaccine strain Flury.Besides,as time goes on,the difference between the epidemic strain and the vaccine strains becomes more and more obvious.The results of this study will provide scientific basis for the development of rabies vaccine and establishment of effective control and prevention measures.