不同纯化方法处理DNA合成引物对PCR扩增效率的影响

对ＤＮＡ合成的幽门螺杆菌尿素酶引物ＨＰ１、ＨＰ２、ＨＰ３、ＨＰ４进行了几种不同的纯化试验，分别采用无水乙醇沉淀法、ＮＴ柱及聚丙烯酰胺凝胶电泳方法，对其相应的纯化收率，ＰＣＲ扩增效率作了比较及分析。琼脂糖凝胶电泳结果证实，以无水乙醇沉淀纯化方法的ＰＣＲ扩增效果较为理想。该方法操作简便、稳定高效、省时省力、成本低。为此建议用该法处理ＤＮＡ合成引物。

Bioleaching of Pb-Zn-Sn chalcopyrite concentrate in tank bioreactor and microbial community succession analysis

The variation of microbial community structure was investigated for the tank bioleaching process of Pb-Zn-Sn chalcopyrite concentrate in the presence of mixed moderately thermophilic bacteria. The parameters, such as pH value, solution potential and concentrations of metal ions, were determined by the method of polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） to analyze the succession of microbial community. The results showed that a final copper extraction rate of 85.6% could be obtained after tank bioleaching for 30 d. The Acidithiobacillus caldus was the dominant population with abundance of about 73.80%in the initial stage, then Sulfobacillus thermosulfidooxidans dominated from the 18th day to the end of bioleaching, while the abundance of Leptospirillum ferriphilum changed slightly. A higher solution potential within a certain range and appropriate concentration of ferric ions were essential for this tank bioleaching of chalcopyrite.

Methodological Studies on Genomic DNA Extraction and Purification from Plant Drug Materials

This paper reports the rationale and methods of DNA extraction and purification from nine species of Compositae and four commercial drugs of corresponding plant Elephantopus scaber. The comparison of three methods: CsCl gradient, CTAB/CsCl gradient and CTAB miniprep extraction by yield, purity and factors affecting PCR was carried out. In conclusion, CTAB miniprep method provides a rapid, effective, economic approach for isolating genomic DNA for Chinese drug identification by genomic fingerprints.

Potentially predictive microRNAs of gastric cancer with metastasis to lymph node

AIM:To detect the expression of 60 microRNAs(miRNAs)in gastric cancer tissues and find new predictive biomarkers of gastric cancer with metastasis.METHODS:The expressions of 60 candidate miRNAs in 30 gastric cancer tissues and paired normal tissues were detected by stem-loop real-time reverse transcription-polymerase chain reaction.After primary screening of miRNAs expression,5 selected miRNAs were further testified in another 22 paired gastric tissues.Based on the expression level of miRNAs and the status of metastasis to lymph node(LN),receiver-operating-characteristic(ROC)curve were used to evaluate their ability in predicting the status of metastasis to LN.RESULTS:Thirty-eight miRNAs expressions in gastric cancer tissues were significantly different from those in paired normal tissues(P<0.01).Among them,31miRNAs were found to be up-expressed in cancer tissues and 1 miRNAs were down-expressed≥1.5 fold vs paired normal gastric tissue.Five microRNAs(miR-125a-3p,miR-133b,miR-143,miR-195 and miR-212)were differently expressed between different metastatic groups in 30 gastric cancer biopsies(P<0.05).Partial correlation analysis showed that hsa-mir-212 and hsa-mir-195 were correlated with the status of metastasis to LN in spite of age,gender,tumor location,tumor size,depth of invasion and cell differentiation.ROC analysis indicated that miR-212 and miR-195 have better sensi-tivities(84.6%and 69.2%,respectively)and specifici-ties(both 100%)in distinguishing biopsies with metastasis to LN from biopsies without metastasis to LN.CONCLUSION:miR-212 and miR-195 could be independent biomarkers in predicting the gastric cancer with metastasis to LN.

Acute pancreatitis in aging animals:Loss of pancreatitis-associated protein protection?

AIM:To investigate the effect of age on severity of acute pancreatitis(AP) using biochemical markers,histology and expression of the protective pancreatitisassociated proteins(PAPs).METHODS:AP was induced via intraductal injection of 4% sodium taurocholate in young and old rats.Sera and pancreata were assayed at 24 h for the parameters listed above;we also employed a novel molecular technique to assess bacterial infiltration using polymerase chain reaction to measure bacterial genomic ribosomal RNA.RESULTS:At 24 h after induction of AP,the pancreata of older animals had less edema(mean ± SE histologic score of young vs old:3.11 ± 0.16 vs 2.50 ±-0.11,P < 0.05),decreased local inflammatory response(histologic score of stromal infiltrate:3.11 ± 0.27 vs 2.00 ± 0.17,P < 0.05) and increased bacterial infiltration(174% ± 52% increase from sham vs 377% ± 4%,P < 0.05).A decreased expression of PAP1 and PAP2 was demonstrated by Western blotting analysis and immunohistochemical staining.There were no differences in serum amylase and lipase activity,or tissue myeloperoxidase or monocyte chemotactic protein-1 levels.However,in the most-aged group,serum C-reactive protein levels were higher(young vs old:0.249 ± 0.04 mg/dL vs 2.45 ± 0.68 mg/dL,P < 0.05).CONCLUSION:In older animals,there is depressed PAP expression related to a blunted inflammatory response in AP which is associated with worsened bacterial infiltration and higher C-reactive protein level;this may explain the more aggressive clinical course.

Significance of regenerating islet-derived type Ⅳ gene expression in gastroenterological cancers

The regenerating islet-derived members （Reg）, a group of small secretory proteins, which are involved in cell proliferation or differentiation in digestive organs, are upregulated in several gastrointestinal cancers, functioning as trophic or antiapoptotic factors. Regenerat- ing islet-derived type Ⅳ （RegⅣ）, a member of the Reg gene family, has been reported to be overexpressed in gastroenterological cancers. RegIV overexpression in tumor cells has been associated with carcinogen- esis, cell growth, survival and resistance to apoptosis. Cancer tissue expressing RegIV is generally associated with more malignant characteristics than that with- out such expression, and RegⅣ is considered a novel prognostic factor as well as diagnostic marker in some gastroenterological cancers. We previously investigated the expression levels of RegⅣ mRNA of 202 surgical colorectal cancer specimens with quantitative real-time reverse-transcriptase polymerase chain reaction and reported that a higher level of RegⅣ gene expression was a significant independent predictor of colorec- tal cancer. The biologic functions of RegⅣ protein in cancer tissue, associated with carcinogenesis, anti- apoptosis and invasiveness, are being elucidated by molecular investigations using transfection techniques or neutralizing antibodies of RegIV, and the feasibility of antibody therapy targeting RegIV is being assessed. These studies may lead to novel therapeutic strate- gies for gastroenterological cancers expressing RegⅣ. This review article summarizes the current information related to biological functions as well as clinical impor- tance of RegⅣ gene to clarify the significance of Reg~ expression in gastroenterological cancers.

Bilateral Pheochromocytoma as First Presentation of von Hippel-Lindau Disease in a Chinese Family

Objective To investigate the clinical and genetic features of a Chinese family with yon Hippel- Lindau （VHL） disease revealed by bilateral pheochromocytoma. Methods The proband and other members in a Chinese family with familial pheochromocytoma were clinically evaluated and followed up. Genomic DNA extracted from the peripheral blood of 8 family members （including 3 patients） was amplified by polymerase chain reaction （PCR） and the PCR products were directly sequenced. Results The first presentation in the proband, his mother, and his sister was bilateral pheochromocytoma, and the missense mutation of 695G-A （Arg161Gln） in exon 3 of VHL gene was detected in the three patients. In the follow-up study, the proband and his mother were found to have other VHL tumors, induding retinal and cerebellar hemangioblastomas and pancreatic tumor. Neither clinical presentation of VHL disease nor gene mutation was found in other family members. Conclusion VHL disease should be suspected in some patients with familial pheochromocytoma, and VHL gene screening helps to achieve early diagnosis of the disease.

Knockdown of long non-coding RNA LCPAT1 inhibits autophagy in lung cancer

Objective: Long non-coding RNAs(lnc RNAs) are involved in numerous biological processes in lung cancer cells. In our previous studies, we identified a lnc RNA, ENST00000439577, which is highly expressed in lung carcinomas, and termed it lung cancer progression-associated transcript 1(LCPAT1). To characterize the role of LCPAT1 in lung cancer, we conducted the current study.Methods: Expression of LCPAT1 and autophagy-associated markers in tumor tissues and lung cancer cell lines was determined by real-time quantitative polymerase chain reaction(q PCR). Hematoxylin and eosin(HE) staining, q PCR, Western blot, and immunohistochemistry were performed to evaluate xenografted tumor tissues. Autophagy induced by rapamycin was detected by Western blot and immunofluorescence in lung cancer cell lines.Results: Expression of LCPAT1 and microtubule-associated protein 1 light chain 3 beta(LC3B) was positively correlated in lung cancer. Knockdown of LCPAT1 inhibited tumor growth and suppressed cell autophagy in vivo. Moreover, LCPAT1 knockdown in lung cancer cell lines resulted in decreased autophagy-associated gene expression and alleviated the cell autophagy induced by rapamycin.Conclusions: We speculate that LCPAT1 plays a crucial role in regulating autophagy in lung cancer.

Function of chloride intracellular channel 1 in gastric cancer cells

AIM:To investigate the effect of chloride intracellular channel 1(CLIC1) on the cell proliferation,apoptosis,migration and invasion of gastric cancer cells.METHODS:CLIC1 expression was evaluated in human gastric cancer cell lines SGC-7901 and MGC-803 by real time polymerase chain reaction(RT-PCR).Four segments of small interference RNA(siRNA) targeting CLIC1 mRNA and a no-sense control segment were designed by bioinformatics technology.CLIC1 siRNA was selected using Lipofectamine 2000 and transfected transiently into human gastric cancer SGC-7901 and MGC-803 cells.The transfected efficiency was observed under fluorescence microscope.After transfection,mRNA expression of CLIC1 was detected with RT-PCR and Western blotting was used to detect the protein expression.Proliferation was examined by methyl thiazolyl tetrazolium and apoptosis was detected with flow cytometry.Polycarbonate membrane transwell chamber and Matrigel were used for the detection of the changes of invasion and migration of the two cell lines.RESULTS:In gastric cancer cell lines SGC-7901 and MGC-803,CLIC1 was obviously expressed and CLIC1 siRNA could effectively suppress the expression of CLIC1 protein and mRNA.Proliferation of cells transfected with CLIC1 siRNA3 was enhanced notably,and the highest proliferation rate was 23.3%(P = 0.002) in SGC-7901 and 35.55%(P = 0.001) in MGC-803 cells at 48 h.The G2/M phase proportion increased,while G0/G1 and S phase proportions decreased.The apoptotic rate of the CLIC1 siRNA3 group obviously decreased in both SGC-7901 cells(62.24%,P = 0.000) and MGC-803 cells(52.67%,P = 0.004).Down-regulation of CLIC1 led to the inhibition of invasion and migration by 54.31%(P = 0.000) and 33.62%(P = 0.001) in SGC-7901 and 40.74%(P = 0.000) and 29.26%(P = 0.002) in MGC-803.However,there was no significant difference between the mock group cells and the negative control group cells.

Correlation between mitochondrial TRAP-1 expression and lymph node metastasis in colorectal cancer

AIM： To evaluate the effect of mitochondrial tumor ne- crosis factor receptor-associated protein-1 （TRAP-l） on the lymph node metastasis （LNM） in Chinese colorectal cancer （CRC） patients, and develop potential LNM- associated biomarkers for CRC using quantitative real- time polymerase chain reaction （RT-PCR） analysis. METHODS： Differences in mitochondrial TRAP-1 gene expression between primary CRC with LNM （LNM CRC） and without LNM （non-LNM CRC） were assessed in 96 Chinese colorectal carcinoma samples using quantita- tive RT-PCR analysis, Western blotting, and confirmed with immunohistochemical assay. The relationship between clinicopathological parameters and potential diaclnostic biomarkers was also examined.RESULTS： TRAP-1 was significantly upregulated in LNM CRC compared with non-LNM CRC, which was confirmed by RT-PCR, Western blotting and immuno- histochemical assay. The expression of TRAP-1 in two different metastatic potential human colorectal cancer cell lines, LoVo and HT29, was analyzed with Western blotting. The expression level of TRAP-1 was dramati- cally higher in LoVo than in HT29. Overexpression of TRAP-1 was significantly associated with LNM （90.2% in LNM group vs 22% in non-LNM group, P 〈 0.001）, the advanced tumor node metastasis stage （89.1% in LNM group vs 26.9% in non-LNM group, P 〈 0.001）, the increased 5-year recurrence rate （82.7% in LNM group vs 22.6% in non-LNM group, P 〈 0.001） and the decreased 5-year overall survival rate （48.4% in LNM vs 83.2% in non-LNM group, P 〈 0.001）. Univariate and multivariate analyses indicated that TRAP-1 expression was an independent prognostic factor for recurrence and survival of CRC patients （Hazard ratio of 2.445 in recurrence, P = 0.017; 2.867 in survival, P = 0.028）. CONCLUSION： Mitochondria TRAP-1 affects the lymph node metastasis in CRC, and may be a potential bio- marker for LNM and a prognostic factor in CRC. Over- expression of TRAP-1 is a predictive factor for the poor outcome of colorectal cancer patients. 2012 Baishideng. All rights reserved

Tenofovir rescue therapy for chronic hepatitis B patients after multiple treatment failures

AIM:To evaluate the efficacy and safety of tenofovir disoproxil fumarate(TDF) for chronic hepatitis B(CHB) patients after multiple failures.METHODS:A total of 29 CHB patients who had a suboptimal response or developed resistance to two or more previous nucleoside/nucleotide analogue(NA) treatments were included.Study subjects were treated with TDF alone(n = 13) or in combination with lamivudine(LAM,n = 12) or entecavir(ETV,n = 4) for ≥ 6 mo.Complete virologic response(CVR) was defined as an achievement of serum hepatitis B virus(HBV) DNA level ≤ 60 IU/mL by real-time polymerase chain reaction method during treatment.Safety assessment was based on serum creatinine and phosphorus level.Eleven patients had histories of LAM and adefovir dipivoxil(ADV) treatment and 18 patients were exposed to LAM,ADV,and ETV.Twenty-seven patients(93.1%) were hepatitis B e antigen(HBeAg) positive and the mean value of the baseline serum HBV DNA level was 5.5 log IU/mL ± 1.7 log IU/mL.The median treatment duration was 16 mo(range 7 to 29 mo).RESULTS:All the patients had been treated with LAM and developed genotypic and phenotypic resistance to it.Resistance to ADV was present in 7 patients and 10 subjects had a resistance to ETV.One patient had a resistance to both ADV and ETV.The cumulative probabilities of CVR at 12 and 24 mo of TDF containing treatment regimen calculated by the Kaplan Meier method were 86.2% and 96.6%,respectively.Although one patient failed to achieve CVR,serum HBV DNA level decreased by 3.9 log IU/mL from the baseline and the last serum HBV DNA level during treatment was 85 IU/mL,achieving near CVR.No patients in this study showed viral breakthrough or primary non-response during the follow-up period.The cumulative probability of HBeAg clearance in the 27 HBeAg positive patients was 7.4%,12%,and 27% at 6,12,and 18 mo of treatment,respectively.Treatment efficacy of TDF containing regimen was not statistically different according to the presence of specific HBV mutations.History of prior exposure to specific antiviral agents did not make a difference to treatment outcome.Treatment efficacy of TDF was not affected by combination therapy with LAM or ETV.No patient developed renal toxicity and no cases of hypophosphatemia associated with TDF therapy were observed.There were no other adverse events related to TDF therapy observed in the study subjects.CONCLUSION:TDF can be an effective and safe rescue therapy in CHB patients after multiple NA therapy failures.

RRAS:A key regulator and an important prognostic biomarker in biliary atresia

AIM:To characterize the differentially expressed gene profiles in livers from biliary atresia (BA) patients including,ascertain genes,functional categories and pathways that play a central role in the pathogenesis of BA,and identify the novel prognostic markers for BA.METHODS:Liver tissue samples from control patients,neonatal cholestasis patients,and BA patients at the age of < 60 d,60-90 d,and > 90 d were pooled for DNA microarray analysis.Bioinformatics analysis was performed using,series test cluster of gene ontology,and Pathway-Finder software.Reverse-transcription polymerase chain reaction was performed to confirm changes in selected genes.Relation between RRAS gene expression and prognosis of 40 BA patients was analyzed in a 2-year follow-up study.RESULTS:The 4 identified significant gene expression profiles could confidently separate BA liver tissue from normal and other diseased liver tissues.The included genes were mainly involved in inflammation response and reconstruction of cellular matrix.The significant pathways associated with BA were primarily involved in autoimmune response,activation of T lymphocytes and its related cytokines.The RRAS,POMC,SLC26A6 and STX3 genes were important regulatory modules in pathogenesis of BA.The expression of RRAS was negatively correlated with the elimination rate of jaundice and positively correlated with the occurrence rate of cholangitis.CONCLUSION:Autoimmune response mediated by T lymphocytes may play a vital role in the pathogenesis of BA.The RRAS gene is an important regulatory module in the pathogenesis of BA,which may serve as a novel prognostic marker for BA.

The Role of the Charged Residues of the GP2 Helical Regions in Ebola Entry

The glycoprotein （GP） of Ebola is the sole structural protein that forms the spikes on the viral envelope. The GP contains two subunits, GPI and GP2, linked by a disulfide bond, which are responsible for receptor binding and membrane fusion, respectively. In this study, the full length of GP gene of Ebola Zaire species, 2028 base pairs in length, was synthesized using 38 overlapping oligonucleotides by multiple rounds of polymerase chain reaction （PCR）. The synthesized GP gene was shown to be efficiently expressed in mammalian cells. Furthermore, an efficient HIV-based pseudotyping system was developed using the synthetic GP gene, providing a safe approach to dissecting the entry mechanism of Ebola viruses. Using this pseudotyping system and mutational analysis, the role of the charged residues in the GP2 helical regions was examined. It was found that substitutions of the most charged residues in the regions did not adversely affect GP expression, processing, or viral incorporation, however, most of the mutations greatly impaired the ability of GP to mediate efficient viral infection. These results demonstrate that these charged residues of GP2 play an important role in GP-mediated Ebola entry into its host cells. We propose that these charged residues are involved in forming the intermediate conformation（s） of GP in membrane fusion and Ebola entry.

Human Cytomegalovirus UL138 Open Reading Frame Is Highly Conserved in Clinical Strains

Objective To investigate the variability of human cytomegalovirus （HCMV） UL138 open reading frame （ORF） in clinical strains. Methods HCMV UL138 ORF was amplified by polymerase chain reaction （PCR） and PCR amplification products were sequenced directly, and the data were analyzed in 19 clinical strains. Results LIL138 ORF in all 30 clinical strains was amplified successfully. Compared with that of Toledo strain, the nucleotide and amino acid sequence identifies of LIL138 ORF in all strains were 97.41% to 99.41% and 98.24% to 99.42%, respectively. All of the nucleofide mutations were substitutions. The spatial structure and post-translational modification sites of HL138 encoded proteins were conserved. The result of phylogenetic tree showed that HCMV HL138 sequence variations were not definitely related with different clinical symptoms. Conclusion HCMV UL138 ORF in clinical strains is high conservation, which might be helpful for UL138 encoded protein to play a role in latent infection of HCMV.

Helicobacter species and gut bacterial DNA in Meckel's diverticulum and the appendix

AIM:To analyse the possible association of various Helicobacter species and certain common gut bacteria in patients with Meckel's diverticulum and appendicitis.METHODS:A nested-polymerase chain reaction (PCR),specific to 16S rRNA of the Helicobacter genus,was performed on paraffin embedded samples,50 with acute appendicitis,50 normal appendixes,and 33 Meckel's diverticulum with gastric heterotopia and/or ulcer.Helicobacter genus positive samples were sequenced for species identification.All samples were also analysed for certain gut bacteria by PCR.RESULTS:Helicobacter pullorum DNA was found in one out of 33 cases and Enterobacteria in two cases of Meckel's diverticulum.Helicobacter pylori (H.pylori) was found in three,Enterobacter in 18,and Bacteroides in 19 out of 100 appendix samples by PCR.Enterococcus was not found in any MD or appendix samples.All H.pylori positive cases were from normal appendixes.CONCLUSION:Helicobacter is not an etiological agent in the pathogenesis of symptomatic Meckel's diverticulum or in acute appendicitis.

High level of urokinase plasminogen activator contributes to cholangiocarcinoma invasion and metastasis

AIM: To investigate the role of urokinase plasminogen activator (uPA) in cholangiocarcinoma (CCA) invasion and its correlation with clinicopathological parameters. METHODS: uPA expression in CCA tissue was determined by immunohistochemistry. The level of uPA from two CCA cell lines (HuCCA-1 and KKU-M213) and a noncancer immortalized cholangiocyte cell line (H69) was monitored by plasminogen-gelatin zymography and western blotting, whereas that of plasminogen activator inhibitor type 1 (PAI-1) protein and uPA receptor (uPAR)mRNA was monitored by western blotting and quantitative real-time reverse transcriptase polymerase chain reaction, respectively. Two independent methods were employed to suppress uPA function: a synthetic uPA inhibitor (B428) and silencing of uPA gene expression using siRNA. In vitro invasion of the uPA-disrupted cells was assessed by Matrigel-coated Transwell assay. RESULTS: The immunohistochemical study showed that 75.3% (131/174) of CCA tissues expressed uPA. High uPA expression was correlated with lymphatic invasion and metastasis of CCA patients. Plasminogen-gelatin zymography of the conditioned media and cell-surface eluates showed that both CCA cell lines, but not H69, expressed both secreted and membrane-bound forms of uPA. Although the two CCA cell lines, HuCCA-1 and KKU-M213, expressed a relatively high level of uPA and uPAR, the latter exhibited a much lower degree of in vitro invasiveness, correlating with a high expression of PAI-1 in the latter, but not in the former. Suppressing uPA function with a specific uPA inhibitor, B428, or with siRNA against uPA reduced in vitro invasiveness of KKU-M213 cells, demonstrating the requirement for uPA in the invasiveness of CCA cells. Therefore, our in vivo and in vitro studies suggest that uPA is an important requirement for the invasion process of CCA. CONCLUSION: uPA expression correlates with lymphatic invasion and metastasis in vivo and is required for CCA cell invasion in vitro , suggesting its potential as a therapeutic target.

Identification and Diagnostics of Plant-Symbiotic and Phytopathogenic Bacteria

Rapid and reliable diagnostics and identification of pathogenic and symbiotic bacteria are at the top of the agenda. In the first case, they are important to control and prevent crop damages, and thus reduce economic losses. In the second, it＇s necessary to design and monitor quality of biofertilizer to raise its effectiveness and crop capacity. Development of accurately, rapidly, technically and commercially accessible methods remains a critical problem for the bacteria with comprehensive phylogenetic structure. In this work, we investigated pathogenic Xanthomonas and Ralstonia and symbiotic Sinorhizobium. The aim of this investigation was to examine the applicability of the novel methods for phylogenetic study, identification and diagnostics of closely related species of these genera. The conventional phenotypic and genotypic （16S rRNA, gyrB） methods were applied as referents. Novel polymerase chain reaction （PCR）-based approaches, single-adapter amplified fragment length polymorphism （saAFLP） and comparative analyses of hin-region and Xcc0006-0007 sequences, were first employed for the investigations. Phenotypic tests, 16S rRNA and gyrB analysis distinguished bacteria at the genus level, but failed to identify them to the species robustly. The new methods identified bacteria at the inter-species level more precisely. This identification agreed with the accepted genera＇s classifications. The only exceptions were X. fuscans ＆ X. cirri and X. perforance ＆ X. euvesicatoria which clustered together. The further outcome of this study was achieved hin-region-based genus-specific PCR primers for the express-diagnostics of the genera. Summary, these new methods can be applied for genome-based phylogeny investigations and as convenient and accurate tools for identification and routine laboratory diagnostics of these comprehensive genera.

A Few Questions that Should be Clarified in the Polymerase Chain Reaction

The polymerase chain reaction is one of the most useful technical ad- vance and inventions in modern molecular biology. Developed in 1983 by Kary Mullis, PCR is now a common and indispensable technique used in medical and bi- ology research labs for a variety of applications. A large number of articles relat- ed to PCR are available on the internet and other places. People know well about the basic principle and are very familiar with the procedures of the PCR. But, some details were neglected on the numbers of the target sequence and other DNA strands number after 30 to 35 cycles of the PCR. In most papers, the number of newly synthesized DNA strands including target DNA and non target DNA is am- biguous and even wrong. In this paper, highlights were given to the theoretical number of target DNA number in details and the exact number of the target DNA number can be concluded by analysis.

Nontuberculous Mycobacteria Infections in Katavi Rukwa Ecosystems

A study on nontuberculous mycobacteria （NTM） was carried out in wildlife-livestock interface of Katavi Rukwa ecosystem （KRE）. 328 livestock tissues and 178 wild animals were cultured, wild animals were sampled opportunistically during professional hunting and game cropping operations in the KRE protected areas. The objective of the study was to generate data on epidemiology of NTM in the wildlife-livestock interface of the KRE. Methods used to identify the NTM were： culture and isolation, polymerase chain reaction, protein heat shock 65 kilodalton （hsp65） and sequencing. Mycobacteria were detected on 25.9% and 11.9% of livestock and wildlife tissue cultures, respectively. The most NTM isolated were M. kansasii （30%）, M. gastri （30%）, M. fortuitum （1%）, M. intracellulare （4%）, M. indicuspranii （4%）, M. nonchromogenicum （6%） and M. lentiflavum （6%）. Other NTM in smaller percentages were M. hibernae, M. engbaekii, M. septicum, M. arupense and 34.. godii. Due to rise of NTM infection in both human and animals, it is recommended that awareness and laboratory facilities be improved to curb the underreporting especially in TB-endemic countries. For species specific identification, a network of national and regional laboratories is promoted.