Background: Hand, foot and mouth disease (HFMD) remains an important public health problem in China. Many studies on the epidemiological characteristics of HFMD have been reported, but studies in North Sichuan region ...Background: Hand, foot and mouth disease (HFMD) remains an important public health problem in China. Many studies on the epidemiological characteristics of HFMD have been reported, but studies in North Sichuan region have been neglected. Methods: HFMD-related enterovirus infected cases were clinically confirmed and underwent real-time RT-PCR (rRT-PCR) from May 2018 to October 2023 in Guangyuan Central Hospital. Results: During 2018-2023, other EV (437 cases, 81.08%) was the most predominant serotype followed by CV-A16 (94 cases, 17.44%), EV-A71 (8 cases, 1.48%) was the least predominant serotype. Peak infections occurred in July and October. There were no significant differences in gender, age and serotypes. HFMD was concentrated in children under 47 months of age, with the highest incidence in children aged 12 - 23 months and the highest proportion of other EV infections in the whole age group. COVID-19 did not cause significant changes in gender, age and serotype. Overall, there was a significant increase in the proportion of children aged 12 - 23 months infected with CV-A16, and an increase in the proportion of children aged over 36 months infected with other EVs. Conclusions: The incidence of HFMD caused by EV-A71 has decreased significantly, and other EVs have become the main pathogens of HFMD in North Sichuan region in recent years. In the prevention and control of CV-A16, more attention should be paid to children aged 12 - 23 months and the dominant serotype should be closely monitored. Our study highlights the importance of developing of new diagnostic reagents and vaccines for the prevention and control of enterovirus infection. This study for the first time provides insights into district interventions to local conditions.展开更多
Streptococcus agalactiae is one of the most common pathogens that cause bovine mastitis worldwide. Identifying pathogen prevalence and virulence factors is critical for developing prevention and control approaches. He...Streptococcus agalactiae is one of the most common pathogens that cause bovine mastitis worldwide. Identifying pathogen prevalence and virulence factors is critical for developing prevention and control approaches. Herein, 1 161 milk samples from various dairy farms in China(n=558) and Pakistan(n=603) were collected between 2019–2021 and were subjected to S. agalactiae isolation. Prevalence, serotyping, virulence genes, and antibiotic-resistant genes of S. agalactiae were evaluated by PCR assay. All isolates were characterized for haemolysis, biofilm production, cytotoxicity, adhesion, and invasion on bovine mammary epithelial cells. The prevalence of S. agalactiae-induced mastitis in cattle was found to be considerably higher in Pakistan than in China. Jiangsu and Sindh provinces had the highest area-wise prevalence in China and Pakistan, respectively. Serotypes Ia and II were prevalent in both countries, whereas serotype III was found only in Pakistan. Moreover, all isolates tested positive for PI-2b gene but negative for PI-1 and PI-2a genes. All isolates harboured cfb, cylE, hylB, and fbsB virulent genes, whereas many of them lacked bibA, rib and bca. However, the absence of bac and scp genes in Chinese isolates and cspA in Pakistani isolates was noted, while spb1 and lmb were not detected in isolates of both countries. Pakistani isolates, particularly serotype Iapositive, had a considerably higher ability to produce biofilm, haemolysis, cytotoxicity, adhesion, and invasion than Chinese isolates. Most of the isolates were phenotypically resistant to tetracycline, erythromycin, and clindamycin and genotypic resistance was confirmed by the presence of ermA, ermB, tetM and tetO genes. Our study highlights the antimicrobial resistance profile and virulence-related factors contributing to the epidemiological spread of mastitis-causing S. agalactiae in China and Pakistan. The findings may facilitate future studies designed to develop improved treatment and control strategies against this pathogen.展开更多
Gallbladder cancer is a malignancy of biliary tract which is infrequent in developed countries but common in some specific geographical regions of developing countries. Late diagnosis and deprived prognosis are major ...Gallbladder cancer is a malignancy of biliary tract which is infrequent in developed countries but common in some specific geographical regions of developing countries. Late diagnosis and deprived prognosis are major problems for treatment of gallbladder carcinoma. The dramatic associations of this orphan cancer with various genetic and environmental factors are responsible for its poorly defined pathogenesis. An understanding to the relationship between epidemiology, molecular genetics and pathogenesis of gallbladder cancer can add new insights to its undetermined pathophysiology. Present review article provides a recent update regarding epidemiology, pathogenesis, and molecular genetics of gallbladder cancer. We systematically reviewed published literature on gallbladder cancer from online search engine Pub Med(http://www.ncbi.nlm.nih.gov/pubmed). Various keywords used for retrieval of articles were Gallbladder, cancer Epidemiology, molecular genetics and bullion operators like AND, OR, NOT. Cross references were manually searched from various online search engines(http://www.ncbi.nlm.nih.gov/pubmed,https://scholar.google.co.in/, http://www.medline.com/home.jsp). Most of the articles published from 1982 to 2015 in peer reviewed journals have been included in this review.展开更多
Molecular pathological epidemiology(MPE) is a multidisciplinary and transdisciplinary study field,which has emerged as an integrated approach of molecular patho-logy and epidemiology,and investigates the relationship ...Molecular pathological epidemiology(MPE) is a multidisciplinary and transdisciplinary study field,which has emerged as an integrated approach of molecular patho-logy and epidemiology,and investigates the relationship between exogenous and endogenous exposure factors,tumor molecular signatures,and tumor initiation,progression,and response to treatment.Molecular epidemiology broadly encompasses MPE and conventional-type molecular epidemiology.Hepatocellular carcinoma(HCC) is the third most common cause of cancer-associated death worldwide and remains as a major public health challenge.Over the past few decades,a number of epidemiological studies have demonstrated that diabetes mellitus(DM) is an established independent risk factor for HCC.However,how DM affects the occurrence and development of HCC remains as yet unclearly understood.MPE may be a promising approach to investigate the molecular mechanisms of carcinogenesis of DM in HCC,and provide some useful insights for this pathological process,although a few challenges must be overcome.This review highlights the recent advances in this field,including:(1) introduction of MPE;(2) HCC,risk factors,and DM as an established independent risk factor for HCC;(3) molecular pathology,molecular epidemiology,and MPE in DM and HCC;and(4) MPE studies in DM and risk of HCC.More MPE studies are expected to be performed in future and I believe that this field can provide some very important insights on the molecular mechanisms,diagnosis,personalized prevention and treatment for DM and risk of HCC.展开更多
Nipah virus(Ni V) is a member of the genus Henipavirus of the family Paramyxoviridae,characterized by high pathogenicity and endemic in South Asia.It is classified as a Biosafety Level-4(BSL-4) agent.The case-fatality...Nipah virus(Ni V) is a member of the genus Henipavirus of the family Paramyxoviridae,characterized by high pathogenicity and endemic in South Asia.It is classified as a Biosafety Level-4(BSL-4) agent.The case-fatality varies from 40%-70% depending on the severity of the disease and on the availability of adequate healthcare facilities.At present no antiviral drugs are available for Ni V disease and the treatment is just supportive.Phylogenetic and evolutionary analyses can be used to help in understanding the epidemiology and the temporal origin of this virus.This review provides an overview of evolutionary studies performed on Nipah viruses circulating in different countries.Thirty phylogenetic studies have been published from 2000 to 2015 years,searching on pub-med using the key words ‘Nipah virus AND phylogeny' and twenty-eight molecular epidemiological studies from 2006 to 2015 have been performed,typing the key words ‘Nipah virus AND molecular epidemiology'.Overall data from the published study demonstrated as phylogenetic and evolutionary analysis represent promising tools to evidence NiV epidemics,to study their origin and evolution and finally to act with effective preventive measure.展开更多
Hand, foot, and mouth disease (HFMD) is a common contagious illness which occurs worldwide both sporadically and in epidemics. The disease mainly affects, children and the typical symptoms, which may resolve spontan...Hand, foot, and mouth disease (HFMD) is a common contagious illness which occurs worldwide both sporadically and in epidemics. The disease mainly affects, children and the typical symptoms, which may resolve spontaneously, include mucocutaneous papulovesicular lesions on the hands, feet, mouth, and buttocks. In rare cases, however, the patients may also develop neurological complications such as neurogenic pulmonary edema,展开更多
Objective To trace the source of human H7N9 cases in Huai'an and elucidate the genetic characterization of Huai'an strains associated with both humans and birds in live poultry market.Methods An enhanced surveillanc...Objective To trace the source of human H7N9 cases in Huai'an and elucidate the genetic characterization of Huai'an strains associated with both humans and birds in live poultry market.Methods An enhanced surveillance was implemented when the first human H7N9 case was confirmed in Huai'an.Clinical specimens,cloacal swabs,and fecal samples were collected and screened by real-time reverse transcription-polymerase chain reaction(RT-PCR) for H7N9 virus.The positive samples were subjected to further RT-PCR and genome sequencing.The phylodynamic patterns of H7N9 virus within and separated from Huai'an and evolutionary dynamics of the virus were analyzed.Results Six patients with H7N9 infection were previously exposed to live poultry market and presented symptoms such as fever(〉38.0 °C) and headaches.Results of this study support the hypothesis that live poultry markets were the source of human H7N9 exposure.Phylogenetic analysis revealed that all novel H7N9 viruses,including Huai'an strains,could be classified into two distinct clades,A and B.Additionally,the diversified H7N9 virus circulated in live poultry markets in Huai'an.Interestingly,the common ancestors of the Huai'an H7N9 virus existed in January 2012.The mean nucleotide substitution rates for each gene segment of the H7N9 virus were(3.09-7.26)×10-3 substitutions/site per year(95% HPD:1.72×10-3 to 1.16×10-2).Conclusion Overall,the source of exposure of human H7N9 cases in Huai'an was live poultry market,and our study highlights the presence of divergent genetic lineage of H7N9 virus in both humans and poultry specimens in Huai'an.展开更多
Hand,foot and mouth disease(HFMD)is a common infectious disease that usually affects children less than 5 years of age.HFMD is caused by human enteroviruses(HEVs).HEVs,members of the Enterovirus genus of the Picornavi...Hand,foot and mouth disease(HFMD)is a common infectious disease that usually affects children less than 5 years of age.HFMD is caused by human enteroviruses(HEVs).HEVs,members of the Enterovirus genus of the Picornaviridae(small RNA virus)family.展开更多
The Asia-Pacific region is a home to 60% of the population in the world and to approximately one quarter of people with HIV/AIDS. Close to a million of people has been infected and a half million people died of AIDS a...The Asia-Pacific region is a home to 60% of the population in the world and to approximately one quarter of people with HIV/AIDS. Close to a million of people has been infected and a half million people died of AIDS annually in Asia,becoming the second largest epicenter of global AIDS epidemic. Molecular epidemiology has been useful tool to track a course of HIV spread. In-depth knowledge from the studies on molecular epidemiology elucidates the dynamics of HIV spread and the interrelationship of epidemics in the different regions in Asia.展开更多
Neospora caninum (N. caninum), a cyst-forming protozoan parasite, is a major cause of bovine abortions and neonatal mortality worldwide. N. caninum has a broad intermediate host range, and its sexual cycle occurs excl...Neospora caninum (N. caninum), a cyst-forming protozoan parasite, is a major cause of bovine abortions and neonatal mortality worldwide. N. caninum has a broad intermediate host range, and its sexual cycle occurs exclusively in canids. Another species of Neospora, Neospora hughesi (N. hughesi), has been identified and causes myeloencephalitis in horses. Although molecular epidemiology studies are in their infancy, the 18S ribosomal RNA (rRNA) and ITS1 regions within the small subunit ribosomal RNA (ssuRNA) and an N. caninum species-specific DNA probe (pNc5) have been used extensively to differentiate Neospora from other closely related apicomplexan parasites. While these repetitive regions have higher sensitivity and specificity than housekeeping or antigen genes, they suffer from low discriminatory power and fail to capture intra-species diversity. Similarly, although multiple minisatellite or microsatellite marker studies have shown clear geographic substructures within Neospora, strains are often misclassified due to a convergence in the size of different alleles at microsatellite loci, known as homoplasy. Only one strain, N. caninum Liverpool (Nc-Liv), has been genome sequenced and compared with its closest relative, Toxoplasma gondii (T. gondii). Hence, detailed population genomics studies based on whole-genome sequences from multiple strains worldwide are needed in order to better understand the current population genetic structure of Neospora, and ultimately to determine more effective vaccine candidates against bovine neosporosis. The aim of this review is to outline our current understanding of the molecular epidemiology and genomics of Neospora in juxtaposition with the closely related apicomplexan parasites Hammondia hammondi and T. gondii.展开更多
AIM:To study the subtype prevalence and the phylogenetic relatedness of hepatitis C virus(HCV)sequences obtained from the Argentine general population,a large cohort of individuals was analyzed.METHODS:Healthy Argenti...AIM:To study the subtype prevalence and the phylogenetic relatedness of hepatitis C virus(HCV)sequences obtained from the Argentine general population,a large cohort of individuals was analyzed.METHODS:Healthy Argentinian volunteers(n=6251)from 12 provinces representing all geographical regions of the country were studied.All parents or legal guardians of individuals younger than 18 years provided informed written consent for participation.The corresponding written permission from all municipal authorities was obtained from each city or town where subjects were to be included.HCV RNA reverse transcription-polymerase chain reaction products were sequenced and phylogenetically analyzed.The 5’untranslated region(5’UTR)was used for RNA detection and initial genotype classification.The NS5B polymerase region,encompassing nt 8262-8610,was used for subtyping.RESULTS:An unexpectedly low prevalence of HCV infection in the general population(0.32%)was observed.Our data contrasted with previous studies that reported rates ranging from 1.5%to 2.5%,mainly performed in selected populations of blood donors or vulnerable groups.The latter values are in keeping with the prevalence reported by the 2007 Argentinian HCV Consensus(approximately 2%).HCV subtypes weredistributed as follows:1a(25%),1b(25%),2c(25%),3a(5%),and 2j(5%).Two isolates ascribed either to genotype 1(5%)or to genotype 3(5%)by 5’UTR phylogenetic analysis could not be subtyped.Subtype 1a sequences comprised a highly homogeneous population and clustered with United States sequences.Genotype1b sequences represented a heterogeneous population,suggesting that this genotype might have been introduced from different sources.Most subtype 2c sequences clustered close to the 2c reported from Italy and Southern France.CONCLUSION:HCV has a low prevalence of 0.32%in the studied general population of Argentina.The pattern of HCV introduction and transmission in Argentina appears to be a consequence of multiple events and different for each subtype.展开更多
Examples of practical approaches to molecular epidemiology of human cancer are described. Biomarkers of carcinogen exposure or inherited host factors for cancer susceptibility are discussed. Major advances have been m...Examples of practical approaches to molecular epidemiology of human cancer are described. Biomarkers of carcinogen exposure or inherited host factors for cancer susceptibility are discussed. Major advances have been made in the detection of carcinogen-macromolecular adducts through the use of high performance liquid chromatography, immunoaffinity chromatography, the 32P-postlabeling assay, enzyme immunoassays, gas chromatography/mass spectroscopy and synchronous spectrophotofluorimetry. The polycyclic aromatic hydrocarbon- DNA adducts are the most extensively studied in this field and together with antibodies to these adducts found in human serum, they have become useful indicators of exposure to carcinogens. Assays for various kinds of alky 1-DNA adducts have also been developed and the presence of these adducts have been documented in human tissues. Carcinogen-protein adducts have proven to be useful molecular dosimeters of carcinogen exposure. For example, 4-aminobiphenyl hemoglobin adducts are highly correlated with exposure to tobacco smoke. The study of the molecular aspects of interindividual differences in the metabolism and activation of xenobiotics and other genetic markers [DNA-restriction fragment length polymorphisms (RFLPs), mutations, and functional loss of specific genes in carcinogenesis] is an emerging new field that is discussed in the context of genetic susceptibility to cancer. The cytochrome P450 phenotypes and acetylation phenotype are examples of genetic markers that indicate an individual's potential for metabolism of exogenous substances. Further, inherited genetic polymorphic markers, e.g., DNA-RFLPs at protooncogene loci (HRAS-1 and L-myc) have been examined in a case-control study of lung cancer. Data concerning mutations of protooncogenes (H-, K-, and N-RAS) and tumor suppressor genes (retinoblastoma and p53 genes) in various common cancers are providing evidence of multiple genetic lesions that occur during the multistage process of carcinogenesis.展开更多
Although safe and effective vaccines against hepatitis B virus(HBV) have been available for three decades, HBV infection remains the leading cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma(HCC) worl...Although safe and effective vaccines against hepatitis B virus(HBV) have been available for three decades, HBV infection remains the leading cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma(HCC) worldwide, especially in Asian countries. HBV has been classified into at least 9 genotypes according to the molecular evolutionary analysis of the genomic DNA sequence and shown to have a distinct geographical distribution. Novel HBV genotypes/subgenotypes have been reported, especially from Southeast Asian countries. The clinical characteristics and therapeutic effectiveness of interferon(IFN) and nucleos(t)ide analogues vary among different HBV genotypes. Mutations at T1653 C in subgenotype C2 from Japan and South Korea, C/A1753 T and C1858 T in subgenotype C1 from Vietnam, and C1638 T and T1753 V in subgenotype B3 from Indonesia were reported to be associated with advanced liver diseases including HCC. Genotype distribution in Japan has been changed by an increasing ratio of subgenotype A2 in chronic hepatitis B. While a large number of epidemiological and clinical studies have been reported from Asian countries, most of the studies were conducted in developed countries such as Taiwan, China, South Korea and Japan. In this review, the most recent publications on the geographical distribution of genetic variants of HBV and related issues such as disease progression and therapy in Asia are updated and summarized.展开更多
In the 1970s,scientists learned of a new pathogen causing non-A,non-B hepatitis.Classical approaches were used to isolate and characterize this new pathogen,but it could be transmitted experimentally only to chimpanze...In the 1970s,scientists learned of a new pathogen causing non-A,non-B hepatitis.Classical approaches were used to isolate and characterize this new pathogen,but it could be transmitted experimentally only to chimpanzees and progress was slow until the pathogen was identified as hepatitis C virus(HCV)in 1989.Since then,research and treatment of HCV have expanded with the development of modern biological medicine:HCV genome organization and polyprotein processing were delineated in 1993;the first three-dimensional structure of HCV nonstructural protein(NS3 serine protease)was revealed in 1996;an infectious clone of HCV complementary DNA was first constructed in 1997;interferon and ribavirin combination therapy was established in 1998 and the therapeutic strategy gradually optimized;the HCV replicon system was produced in1999;functional HCV pseudotyped viral particles were described in 2003;and recombinant infectious HCV in tissue culture was produced successfully in 2005.Recently,tremendous advances in HCV receptor discovery,understanding the HCV lifecycle,decryption of the HCV genome and proteins,as well as new anti-HCV compounds have been reported.Because HCV is difficult to isolate and culture,researchers have had to avail themselves to the best of modern biomedical technology;some of the major achievements in HCV research have not only advanced the understanding of HCV but also promoted knowledge of virology and cellular physiology.In this review,we summarize the advancements and remaining scotomas in the molecular virology and epidemiology of HCV.展开更多
Although tobacco and alcohol consumption are two common risk factors of head and neck cancer (HNC), other specific etiologic causes, such as viral infection and genetic susceptibility factors, remain to be understoo...Although tobacco and alcohol consumption are two common risk factors of head and neck cancer (HNC), other specific etiologic causes, such as viral infection and genetic susceptibility factors, remain to be understood. Hu- man DNA is often damaged by numerous endogenous and exogenous mutagens or carcinogens, and genetic vari- ants in interaction with environmental exposure to these agents may explain interindividual differences in HNC risk. Single nucleotide polymorphisms (SNPs) in genes involved in the DNA damage-repair response are reported to be risk factors for various cancer types, including HNC. Here, we reviewed epidemiological studies that have assessed the associations between HNC risk and SNPs in DNA repair genes involved in base-excision repair, nucleotide-excision repair, mismatch repair, double-strand break repair and direct reversion repair pathways. We found, however, that only a few SNPs in DNA repair genes were found to be associated with significantly in- creased or decreased risk of HNC, and, in most cases, the effects were moderate, depending upon locus-locus in- teractions among the risk SNPs in the pathways. We believe that, in the presence of exposure, additional pathway- based analyses of DNA repair genes derived from genome-wide association studies (GWASs) in HNC are needed.展开更多
Objective:To detect the subtype characterization and drug-resistant mutations in HIV-1 strains after the refugee movement from Syria to Turkey between 2011 and 2014 in south east border lines. Methods: A total of 65 p...Objective:To detect the subtype characterization and drug-resistant mutations in HIV-1 strains after the refugee movement from Syria to Turkey between 2011 and 2014 in south east border lines. Methods: A total of 65 patients were included in this study, of which 57(88%) patients were antiretroviral therapy-naive patients. HIV-1 RNA was detected and quantii ed by realtime PCR assay. HIV-1 subtypes and circulating recombinant forms(CRFs) were identii ed by phylogenetic analysis(neighbor-joining method), and drug-resistant mutations were analyzed.Results: Three major HIV groups were indicated. Two of these groups were located in subtype B. The other group showed heterogeneity. Subtype B(48/65, 73.8%), followed by CRFs(12/65, 18.5%) was the most common strain. Subtype of CRFs consisted of CRF01_AE(9/65, 13.8%) and CRF02_AG(3/65, 4.6%). Subtype C(1/65, 1.5%), sub-subtypes A1(2/65, 3.1%) and F1(2/65, 3.1%) were also detected with low prevalence. The rate of overall primary antiretroviral resistance was 4.9%(3/61). Drug-resistant rate for non-nucleoside reverse transcriptase inhibitors was 4.9%. The thymidine analogue mutation rate was 13.1%(8/61).Conclusions: HIV molecular epidemiology studies are necessary to determine transmission patterns and spread. Subtype B and CRF01_AE, CRF02_AG are the most prevalent strains in the south-east of Turkey. However, subtype C, sub-subtypes A1 and F1 are of low prevalence but persist in the south-east of Turkey. In the near future, changing of HIV epidemiology will be possible in Turkey due to migration movement in border lines and resistance testing will play an important role in HIV management.展开更多
In the present study, the drug-resistance genes encoding β-lactamases, aminoglycoside modifying enzymes, DNA topoisomerases and integron as well as their molecular epidemiology were investigated by means of analyzing...In the present study, the drug-resistance genes encoding β-lactamases, aminoglycoside modifying enzymes, DNA topoisomerases and integron as well as their molecular epidemiology were investigated by means of analyzing the drug-resistance and molecular epidemiology of Acinebacter baumannii isolated from the clinical samples in two hospitals in Changzhou and Huzhou city of Jiangsu and Zhejiang province from July 2000 to March 2005. The minimal inhibitory concentrations (MICs) of these 307 isolates were detected by automatic microbiological system, and 35 strains against 5-fluoroquinolones were performed by agar dilution assay. Meanwhile, the resistant genes in 80 isolates were amplified by PCR with identification by DNA sequencer. It was found that most of the 307 isolates of A. baumannii were resistant to multiple antibiotics tested, in which the resistance rates of the isolates against piperacillin, piperacillin/tazobactam, amoxacillin/clavulanic acid, cefotaxime, ceftazidime, cefepime, gentamicin, amikacin, ciprofloxacin, chloramphenicol and sulfamethoxazole/trimethoprim were all above 35%, but those of imipenem and meropenem were quite low, ranged only 2.6% and 3.3 %. In addition, it was also demonstrated that the positive rates of TEM and SHV β-lactamase genes accounted for 93.8% and 22.5% respectively, and those of the aminoglycoside-modifying enzyme genes including aacC1, aacC2, aacC3, aacC4, aacC4A, aphA6, ant(2″)-Ⅰ and ant(3″)- Ⅰ were 58.8%, 8.8%, 7.5%, 28.8%, 45.0%, 2.5%, 28.8% and 65.0% respectively. The mutations in the quinolone-resistant determining region (QRDR) of gyrA and parC genes indicated that substitution in Ser-83 residue of GyrA protein was most frequently occurred among strains with MIC for ciprofloxacin of more than 4 μg/ml, whereas a double mutation at Ser-83 residue of gyrA and Ser-80 of parC was found in strains with MIC of ciprofloxacin of more than 8 μg/ml. As to the positive rates of class 1 integron (Int Ⅰ -1) and qacE△1-sul-1, it was found to be 60.0% and 77.5% respectively, and the rates of resistant genes of strains isolated in these two hospitals varied considerably. The results obtained in the present study indicate the presence of the multiple resistant genes in strains of A. baumannii, and great measures should be taken to control the spread of the resistant strains carrying the resistant genes.展开更多
An epidemic of Chinese ferret badger-associated human rabies was investigated in Wuyuan county, Jiangxi province and rabies viruses isolates from ferret badgers in different districts in Jiangxi and Zhejiang provinces...An epidemic of Chinese ferret badger-associated human rabies was investigated in Wuyuan county, Jiangxi province and rabies viruses isolates from ferret badgers in different districts in Jiangxi and Zhejiang provinces were sequenced with their nucleotides and amino acids and aligned for epidemiological analysis. The results showed that the human rabies in Wuyuan are only associated with ferret badger bites; the rabies virus can be isolated in a high percentage of ferret badgers in the epidemic areas in Jiangxi and Zhejiang provinces; the isolates share the same molecular features in nucleotides and have characteristic amino acid signatures, i.e., 2 sites in the nucleoprotein and 3 sites in the glycoprotein, that are distinct from virus isolates from dogs in the same region. We conclude that rabies in Chinese ferret badgers has formed an independent transmission cycle and ferret badgers may serve as another important rabies reservoir independent of dog rabies in China.展开更多
Vascular wilt disease caused by Foe (Fusarium oxysporum f. sp. elaeidis) invades the host xylem and causes a devastating disease of oil palm in west and central Africa. This disease has not been reported in Southeas...Vascular wilt disease caused by Foe (Fusarium oxysporum f. sp. elaeidis) invades the host xylem and causes a devastating disease of oil palm in west and central Africa. This disease has not been reported in Southeast Asia, in spite of long term importation for breeding purposes of African seed and pollen, shown in this laboratory at the University of Bath to be contaminated with Foe disease epidemiology was recently studied in plantations in Ghana. Infection mainly occurred in clusters, implying root-root transmission rather than aerial spread by spores. Molecular diagnostic tools has being developed for: (1) rapid detection and quantification of Foe in plant tissue, soil, seed and pollen for quarantine purposes in order to prevent transcontinental spread of Foe; and (2) to test efficacy of putative disease resistant or tolerant palm genotypes. We have investigated the possibility of Foe-suppressive soils in Malaysia in order to explain the non-appearance of this vascular disease there and possibly to reveal other potential biocontrol agents. The explanation as to why Malaysia has not yet attained the disease is likely to revolve around the soil properties, in particular the microflora. This review reported that greater disease severity based on visual symptoms occurred in autoclaved soils and compost than in untreated soils when oil palm seedlings artificially infected with Foe.展开更多
文摘Background: Hand, foot and mouth disease (HFMD) remains an important public health problem in China. Many studies on the epidemiological characteristics of HFMD have been reported, but studies in North Sichuan region have been neglected. Methods: HFMD-related enterovirus infected cases were clinically confirmed and underwent real-time RT-PCR (rRT-PCR) from May 2018 to October 2023 in Guangyuan Central Hospital. Results: During 2018-2023, other EV (437 cases, 81.08%) was the most predominant serotype followed by CV-A16 (94 cases, 17.44%), EV-A71 (8 cases, 1.48%) was the least predominant serotype. Peak infections occurred in July and October. There were no significant differences in gender, age and serotypes. HFMD was concentrated in children under 47 months of age, with the highest incidence in children aged 12 - 23 months and the highest proportion of other EV infections in the whole age group. COVID-19 did not cause significant changes in gender, age and serotype. Overall, there was a significant increase in the proportion of children aged 12 - 23 months infected with CV-A16, and an increase in the proportion of children aged over 36 months infected with other EVs. Conclusions: The incidence of HFMD caused by EV-A71 has decreased significantly, and other EVs have become the main pathogens of HFMD in North Sichuan region in recent years. In the prevention and control of CV-A16, more attention should be paid to children aged 12 - 23 months and the dominant serotype should be closely monitored. Our study highlights the importance of developing of new diagnostic reagents and vaccines for the prevention and control of enterovirus infection. This study for the first time provides insights into district interventions to local conditions.
基金supported by the National Key Research and Development Program of China (2021YFD1800400)the National Natural Science Foundation of China (31872480)+1 种基金the Jiangsu Agriculture Science and Technology Innovation Fund of China (CX(19)2020)the Priority Academic Program Development of Jiangsu Higher Education Institutions, China (PAPD)。
文摘Streptococcus agalactiae is one of the most common pathogens that cause bovine mastitis worldwide. Identifying pathogen prevalence and virulence factors is critical for developing prevention and control approaches. Herein, 1 161 milk samples from various dairy farms in China(n=558) and Pakistan(n=603) were collected between 2019–2021 and were subjected to S. agalactiae isolation. Prevalence, serotyping, virulence genes, and antibiotic-resistant genes of S. agalactiae were evaluated by PCR assay. All isolates were characterized for haemolysis, biofilm production, cytotoxicity, adhesion, and invasion on bovine mammary epithelial cells. The prevalence of S. agalactiae-induced mastitis in cattle was found to be considerably higher in Pakistan than in China. Jiangsu and Sindh provinces had the highest area-wise prevalence in China and Pakistan, respectively. Serotypes Ia and II were prevalent in both countries, whereas serotype III was found only in Pakistan. Moreover, all isolates tested positive for PI-2b gene but negative for PI-1 and PI-2a genes. All isolates harboured cfb, cylE, hylB, and fbsB virulent genes, whereas many of them lacked bibA, rib and bca. However, the absence of bac and scp genes in Chinese isolates and cspA in Pakistani isolates was noted, while spb1 and lmb were not detected in isolates of both countries. Pakistani isolates, particularly serotype Iapositive, had a considerably higher ability to produce biofilm, haemolysis, cytotoxicity, adhesion, and invasion than Chinese isolates. Most of the isolates were phenotypically resistant to tetracycline, erythromycin, and clindamycin and genotypic resistance was confirmed by the presence of ermA, ermB, tetM and tetO genes. Our study highlights the antimicrobial resistance profile and virulence-related factors contributing to the epidemiological spread of mastitis-causing S. agalactiae in China and Pakistan. The findings may facilitate future studies designed to develop improved treatment and control strategies against this pathogen.
文摘Gallbladder cancer is a malignancy of biliary tract which is infrequent in developed countries but common in some specific geographical regions of developing countries. Late diagnosis and deprived prognosis are major problems for treatment of gallbladder carcinoma. The dramatic associations of this orphan cancer with various genetic and environmental factors are responsible for its poorly defined pathogenesis. An understanding to the relationship between epidemiology, molecular genetics and pathogenesis of gallbladder cancer can add new insights to its undetermined pathophysiology. Present review article provides a recent update regarding epidemiology, pathogenesis, and molecular genetics of gallbladder cancer. We systematically reviewed published literature on gallbladder cancer from online search engine Pub Med(http://www.ncbi.nlm.nih.gov/pubmed). Various keywords used for retrieval of articles were Gallbladder, cancer Epidemiology, molecular genetics and bullion operators like AND, OR, NOT. Cross references were manually searched from various online search engines(http://www.ncbi.nlm.nih.gov/pubmed,https://scholar.google.co.in/, http://www.medline.com/home.jsp). Most of the articles published from 1982 to 2015 in peer reviewed journals have been included in this review.
基金Supported by Beijing NOVA Programme of Beijing Municipal Science and Technology Commission,No.Z13110.7000413067
文摘Molecular pathological epidemiology(MPE) is a multidisciplinary and transdisciplinary study field,which has emerged as an integrated approach of molecular patho-logy and epidemiology,and investigates the relationship between exogenous and endogenous exposure factors,tumor molecular signatures,and tumor initiation,progression,and response to treatment.Molecular epidemiology broadly encompasses MPE and conventional-type molecular epidemiology.Hepatocellular carcinoma(HCC) is the third most common cause of cancer-associated death worldwide and remains as a major public health challenge.Over the past few decades,a number of epidemiological studies have demonstrated that diabetes mellitus(DM) is an established independent risk factor for HCC.However,how DM affects the occurrence and development of HCC remains as yet unclearly understood.MPE may be a promising approach to investigate the molecular mechanisms of carcinogenesis of DM in HCC,and provide some useful insights for this pathological process,although a few challenges must be overcome.This review highlights the recent advances in this field,including:(1) introduction of MPE;(2) HCC,risk factors,and DM as an established independent risk factor for HCC;(3) molecular pathology,molecular epidemiology,and MPE in DM and HCC;and(4) MPE studies in DM and risk of HCC.More MPE studies are expected to be performed in future and I believe that this field can provide some very important insights on the molecular mechanisms,diagnosis,personalized prevention and treatment for DM and risk of HCC.
文摘Nipah virus(Ni V) is a member of the genus Henipavirus of the family Paramyxoviridae,characterized by high pathogenicity and endemic in South Asia.It is classified as a Biosafety Level-4(BSL-4) agent.The case-fatality varies from 40%-70% depending on the severity of the disease and on the availability of adequate healthcare facilities.At present no antiviral drugs are available for Ni V disease and the treatment is just supportive.Phylogenetic and evolutionary analyses can be used to help in understanding the epidemiology and the temporal origin of this virus.This review provides an overview of evolutionary studies performed on Nipah viruses circulating in different countries.Thirty phylogenetic studies have been published from 2000 to 2015 years,searching on pub-med using the key words ‘Nipah virus AND phylogeny' and twenty-eight molecular epidemiological studies from 2006 to 2015 have been performed,typing the key words ‘Nipah virus AND molecular epidemiology'.Overall data from the published study demonstrated as phylogenetic and evolutionary analysis represent promising tools to evidence NiV epidemics,to study their origin and evolution and finally to act with effective preventive measure.
基金supported by National Foundation of China (project No.2013ZX10004-202)National Basic Research Program of China (973 Program,2011CB504902)National Natural Science Foundation of China (project Nos.30900063,81101303,81373049)
文摘Hand, foot, and mouth disease (HFMD) is a common contagious illness which occurs worldwide both sporadically and in epidemics. The disease mainly affects, children and the typical symptoms, which may resolve spontaneously, include mucocutaneous papulovesicular lesions on the hands, feet, mouth, and buttocks. In rare cases, however, the patients may also develop neurological complications such as neurogenic pulmonary edema,
基金supported by grants HAYf201516 from Huai’an Preventive Medicine Associationgrant HAS2015019-3 from Huai’an Scientific Technological Special Project
文摘Objective To trace the source of human H7N9 cases in Huai'an and elucidate the genetic characterization of Huai'an strains associated with both humans and birds in live poultry market.Methods An enhanced surveillance was implemented when the first human H7N9 case was confirmed in Huai'an.Clinical specimens,cloacal swabs,and fecal samples were collected and screened by real-time reverse transcription-polymerase chain reaction(RT-PCR) for H7N9 virus.The positive samples were subjected to further RT-PCR and genome sequencing.The phylodynamic patterns of H7N9 virus within and separated from Huai'an and evolutionary dynamics of the virus were analyzed.Results Six patients with H7N9 infection were previously exposed to live poultry market and presented symptoms such as fever(〉38.0 °C) and headaches.Results of this study support the hypothesis that live poultry markets were the source of human H7N9 exposure.Phylogenetic analysis revealed that all novel H7N9 viruses,including Huai'an strains,could be classified into two distinct clades,A and B.Additionally,the diversified H7N9 virus circulated in live poultry markets in Huai'an.Interestingly,the common ancestors of the Huai'an H7N9 virus existed in January 2012.The mean nucleotide substitution rates for each gene segment of the H7N9 virus were(3.09-7.26)×10-3 substitutions/site per year(95% HPD:1.72×10-3 to 1.16×10-2).Conclusion Overall,the source of exposure of human H7N9 cases in Huai'an was live poultry market,and our study highlights the presence of divergent genetic lineage of H7N9 virus in both humans and poultry specimens in Huai'an.
基金supported by the Chinese National Science and Technology Major Project [2017ZX10104001]Fujian Provincial Natural Science Foundation [NO.2016J01350]the Department of Science and Technology,Fujian Province [NO.2016Y0011]
文摘Hand,foot and mouth disease(HFMD)is a common infectious disease that usually affects children less than 5 years of age.HFMD is caused by human enteroviruses(HEVs).HEVs,members of the Enterovirus genus of the Picornaviridae(small RNA virus)family.
基金Grant support from Ministry of Health, Labour and Welfare and Ministry of Education, Science and Technology in JapanJapanese Foundation for AIDS Prevention.
文摘The Asia-Pacific region is a home to 60% of the population in the world and to approximately one quarter of people with HIV/AIDS. Close to a million of people has been infected and a half million people died of AIDS annually in Asia,becoming the second largest epicenter of global AIDS epidemic. Molecular epidemiology has been useful tool to track a course of HIV spread. In-depth knowledge from the studies on molecular epidemiology elucidates the dynamics of HIV spread and the interrelationship of epidemics in the different regions in Asia.
文摘Neospora caninum (N. caninum), a cyst-forming protozoan parasite, is a major cause of bovine abortions and neonatal mortality worldwide. N. caninum has a broad intermediate host range, and its sexual cycle occurs exclusively in canids. Another species of Neospora, Neospora hughesi (N. hughesi), has been identified and causes myeloencephalitis in horses. Although molecular epidemiology studies are in their infancy, the 18S ribosomal RNA (rRNA) and ITS1 regions within the small subunit ribosomal RNA (ssuRNA) and an N. caninum species-specific DNA probe (pNc5) have been used extensively to differentiate Neospora from other closely related apicomplexan parasites. While these repetitive regions have higher sensitivity and specificity than housekeeping or antigen genes, they suffer from low discriminatory power and fail to capture intra-species diversity. Similarly, although multiple minisatellite or microsatellite marker studies have shown clear geographic substructures within Neospora, strains are often misclassified due to a convergence in the size of different alleles at microsatellite loci, known as homoplasy. Only one strain, N. caninum Liverpool (Nc-Liv), has been genome sequenced and compared with its closest relative, Toxoplasma gondii (T. gondii). Hence, detailed population genomics studies based on whole-genome sequences from multiple strains worldwide are needed in order to better understand the current population genetic structure of Neospora, and ultimately to determine more effective vaccine candidates against bovine neosporosis. The aim of this review is to outline our current understanding of the molecular epidemiology and genomics of Neospora in juxtaposition with the closely related apicomplexan parasites Hammondia hammondi and T. gondii.
基金Supported by Argentinian Fresenius Medical Care CentreSpanish Ministry of Science and Innovation(MINECO)Grants+2 种基金SAF2009-10403Spanish Ministry of Health(FIS)PI10/01505 and 09/0899
文摘AIM:To study the subtype prevalence and the phylogenetic relatedness of hepatitis C virus(HCV)sequences obtained from the Argentine general population,a large cohort of individuals was analyzed.METHODS:Healthy Argentinian volunteers(n=6251)from 12 provinces representing all geographical regions of the country were studied.All parents or legal guardians of individuals younger than 18 years provided informed written consent for participation.The corresponding written permission from all municipal authorities was obtained from each city or town where subjects were to be included.HCV RNA reverse transcription-polymerase chain reaction products were sequenced and phylogenetically analyzed.The 5’untranslated region(5’UTR)was used for RNA detection and initial genotype classification.The NS5B polymerase region,encompassing nt 8262-8610,was used for subtyping.RESULTS:An unexpectedly low prevalence of HCV infection in the general population(0.32%)was observed.Our data contrasted with previous studies that reported rates ranging from 1.5%to 2.5%,mainly performed in selected populations of blood donors or vulnerable groups.The latter values are in keeping with the prevalence reported by the 2007 Argentinian HCV Consensus(approximately 2%).HCV subtypes weredistributed as follows:1a(25%),1b(25%),2c(25%),3a(5%),and 2j(5%).Two isolates ascribed either to genotype 1(5%)or to genotype 3(5%)by 5’UTR phylogenetic analysis could not be subtyped.Subtype 1a sequences comprised a highly homogeneous population and clustered with United States sequences.Genotype1b sequences represented a heterogeneous population,suggesting that this genotype might have been introduced from different sources.Most subtype 2c sequences clustered close to the 2c reported from Italy and Southern France.CONCLUSION:HCV has a low prevalence of 0.32%in the studied general population of Argentina.The pattern of HCV introduction and transmission in Argentina appears to be a consequence of multiple events and different for each subtype.
文摘Examples of practical approaches to molecular epidemiology of human cancer are described. Biomarkers of carcinogen exposure or inherited host factors for cancer susceptibility are discussed. Major advances have been made in the detection of carcinogen-macromolecular adducts through the use of high performance liquid chromatography, immunoaffinity chromatography, the 32P-postlabeling assay, enzyme immunoassays, gas chromatography/mass spectroscopy and synchronous spectrophotofluorimetry. The polycyclic aromatic hydrocarbon- DNA adducts are the most extensively studied in this field and together with antibodies to these adducts found in human serum, they have become useful indicators of exposure to carcinogens. Assays for various kinds of alky 1-DNA adducts have also been developed and the presence of these adducts have been documented in human tissues. Carcinogen-protein adducts have proven to be useful molecular dosimeters of carcinogen exposure. For example, 4-aminobiphenyl hemoglobin adducts are highly correlated with exposure to tobacco smoke. The study of the molecular aspects of interindividual differences in the metabolism and activation of xenobiotics and other genetic markers [DNA-restriction fragment length polymorphisms (RFLPs), mutations, and functional loss of specific genes in carcinogenesis] is an emerging new field that is discussed in the context of genetic susceptibility to cancer. The cytochrome P450 phenotypes and acetylation phenotype are examples of genetic markers that indicate an individual's potential for metabolism of exogenous substances. Further, inherited genetic polymorphic markers, e.g., DNA-RFLPs at protooncogene loci (HRAS-1 and L-myc) have been examined in a case-control study of lung cancer. Data concerning mutations of protooncogenes (H-, K-, and N-RAS) and tumor suppressor genes (retinoblastoma and p53 genes) in various common cancers are providing evidence of multiple genetic lesions that occur during the multistage process of carcinogenesis.
基金Supported by The Japan Initiative for Global Research Network on Infectious Diseases(J-GRID)Program from the Ministry of Education,Culture,Sports,Science and Technology,JapanThe Ministry of Health,Labour and Welfare,Japan,and a SATREPS Grant from Japan Science and Technology Agency and Japan International Cooperation Agency
文摘Although safe and effective vaccines against hepatitis B virus(HBV) have been available for three decades, HBV infection remains the leading cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma(HCC) worldwide, especially in Asian countries. HBV has been classified into at least 9 genotypes according to the molecular evolutionary analysis of the genomic DNA sequence and shown to have a distinct geographical distribution. Novel HBV genotypes/subgenotypes have been reported, especially from Southeast Asian countries. The clinical characteristics and therapeutic effectiveness of interferon(IFN) and nucleos(t)ide analogues vary among different HBV genotypes. Mutations at T1653 C in subgenotype C2 from Japan and South Korea, C/A1753 T and C1858 T in subgenotype C1 from Vietnam, and C1638 T and T1753 V in subgenotype B3 from Indonesia were reported to be associated with advanced liver diseases including HCC. Genotype distribution in Japan has been changed by an increasing ratio of subgenotype A2 in chronic hepatitis B. While a large number of epidemiological and clinical studies have been reported from Asian countries, most of the studies were conducted in developed countries such as Taiwan, China, South Korea and Japan. In this review, the most recent publications on the geographical distribution of genetic variants of HBV and related issues such as disease progression and therapy in Asia are updated and summarized.
文摘In the 1970s,scientists learned of a new pathogen causing non-A,non-B hepatitis.Classical approaches were used to isolate and characterize this new pathogen,but it could be transmitted experimentally only to chimpanzees and progress was slow until the pathogen was identified as hepatitis C virus(HCV)in 1989.Since then,research and treatment of HCV have expanded with the development of modern biological medicine:HCV genome organization and polyprotein processing were delineated in 1993;the first three-dimensional structure of HCV nonstructural protein(NS3 serine protease)was revealed in 1996;an infectious clone of HCV complementary DNA was first constructed in 1997;interferon and ribavirin combination therapy was established in 1998 and the therapeutic strategy gradually optimized;the HCV replicon system was produced in1999;functional HCV pseudotyped viral particles were described in 2003;and recombinant infectious HCV in tissue culture was produced successfully in 2005.Recently,tremendous advances in HCV receptor discovery,understanding the HCV lifecycle,decryption of the HCV genome and proteins,as well as new anti-HCV compounds have been reported.Because HCV is difficult to isolate and culture,researchers have had to avail themselves to the best of modern biomedical technology;some of the major achievements in HCV research have not only advanced the understanding of HCV but also promoted knowledge of virology and cellular physiology.In this review,we summarize the advancements and remaining scotomas in the molecular virology and epidemiology of HCV.
文摘Although tobacco and alcohol consumption are two common risk factors of head and neck cancer (HNC), other specific etiologic causes, such as viral infection and genetic susceptibility factors, remain to be understood. Hu- man DNA is often damaged by numerous endogenous and exogenous mutagens or carcinogens, and genetic vari- ants in interaction with environmental exposure to these agents may explain interindividual differences in HNC risk. Single nucleotide polymorphisms (SNPs) in genes involved in the DNA damage-repair response are reported to be risk factors for various cancer types, including HNC. Here, we reviewed epidemiological studies that have assessed the associations between HNC risk and SNPs in DNA repair genes involved in base-excision repair, nucleotide-excision repair, mismatch repair, double-strand break repair and direct reversion repair pathways. We found, however, that only a few SNPs in DNA repair genes were found to be associated with significantly in- creased or decreased risk of HNC, and, in most cases, the effects were moderate, depending upon locus-locus in- teractions among the risk SNPs in the pathways. We believe that, in the presence of exposure, additional pathway- based analyses of DNA repair genes derived from genome-wide association studies (GWASs) in HNC are needed.
基金Supported by Dicle University Medical Faculty(Grant No.13-TF-91)
文摘Objective:To detect the subtype characterization and drug-resistant mutations in HIV-1 strains after the refugee movement from Syria to Turkey between 2011 and 2014 in south east border lines. Methods: A total of 65 patients were included in this study, of which 57(88%) patients were antiretroviral therapy-naive patients. HIV-1 RNA was detected and quantii ed by realtime PCR assay. HIV-1 subtypes and circulating recombinant forms(CRFs) were identii ed by phylogenetic analysis(neighbor-joining method), and drug-resistant mutations were analyzed.Results: Three major HIV groups were indicated. Two of these groups were located in subtype B. The other group showed heterogeneity. Subtype B(48/65, 73.8%), followed by CRFs(12/65, 18.5%) was the most common strain. Subtype of CRFs consisted of CRF01_AE(9/65, 13.8%) and CRF02_AG(3/65, 4.6%). Subtype C(1/65, 1.5%), sub-subtypes A1(2/65, 3.1%) and F1(2/65, 3.1%) were also detected with low prevalence. The rate of overall primary antiretroviral resistance was 4.9%(3/61). Drug-resistant rate for non-nucleoside reverse transcriptase inhibitors was 4.9%. The thymidine analogue mutation rate was 13.1%(8/61).Conclusions: HIV molecular epidemiology studies are necessary to determine transmission patterns and spread. Subtype B and CRF01_AE, CRF02_AG are the most prevalent strains in the south-east of Turkey. However, subtype C, sub-subtypes A1 and F1 are of low prevalence but persist in the south-east of Turkey. In the near future, changing of HIV epidemiology will be possible in Turkey due to migration movement in border lines and resistance testing will play an important role in HIV management.
文摘In the present study, the drug-resistance genes encoding β-lactamases, aminoglycoside modifying enzymes, DNA topoisomerases and integron as well as their molecular epidemiology were investigated by means of analyzing the drug-resistance and molecular epidemiology of Acinebacter baumannii isolated from the clinical samples in two hospitals in Changzhou and Huzhou city of Jiangsu and Zhejiang province from July 2000 to March 2005. The minimal inhibitory concentrations (MICs) of these 307 isolates were detected by automatic microbiological system, and 35 strains against 5-fluoroquinolones were performed by agar dilution assay. Meanwhile, the resistant genes in 80 isolates were amplified by PCR with identification by DNA sequencer. It was found that most of the 307 isolates of A. baumannii were resistant to multiple antibiotics tested, in which the resistance rates of the isolates against piperacillin, piperacillin/tazobactam, amoxacillin/clavulanic acid, cefotaxime, ceftazidime, cefepime, gentamicin, amikacin, ciprofloxacin, chloramphenicol and sulfamethoxazole/trimethoprim were all above 35%, but those of imipenem and meropenem were quite low, ranged only 2.6% and 3.3 %. In addition, it was also demonstrated that the positive rates of TEM and SHV β-lactamase genes accounted for 93.8% and 22.5% respectively, and those of the aminoglycoside-modifying enzyme genes including aacC1, aacC2, aacC3, aacC4, aacC4A, aphA6, ant(2″)-Ⅰ and ant(3″)- Ⅰ were 58.8%, 8.8%, 7.5%, 28.8%, 45.0%, 2.5%, 28.8% and 65.0% respectively. The mutations in the quinolone-resistant determining region (QRDR) of gyrA and parC genes indicated that substitution in Ser-83 residue of GyrA protein was most frequently occurred among strains with MIC for ciprofloxacin of more than 4 μg/ml, whereas a double mutation at Ser-83 residue of gyrA and Ser-80 of parC was found in strains with MIC of ciprofloxacin of more than 8 μg/ml. As to the positive rates of class 1 integron (Int Ⅰ -1) and qacE△1-sul-1, it was found to be 60.0% and 77.5% respectively, and the rates of resistant genes of strains isolated in these two hospitals varied considerably. The results obtained in the present study indicate the presence of the multiple resistant genes in strains of A. baumannii, and great measures should be taken to control the spread of the resistant strains carrying the resistant genes.
基金supported by the Key Project of National Science Foundation of China (Approval No. 30630049)China National "863" Program (Approval No. 2011AA10A212)the China National "973" Program (Approval No. 2012CB722501)
文摘An epidemic of Chinese ferret badger-associated human rabies was investigated in Wuyuan county, Jiangxi province and rabies viruses isolates from ferret badgers in different districts in Jiangxi and Zhejiang provinces were sequenced with their nucleotides and amino acids and aligned for epidemiological analysis. The results showed that the human rabies in Wuyuan are only associated with ferret badger bites; the rabies virus can be isolated in a high percentage of ferret badgers in the epidemic areas in Jiangxi and Zhejiang provinces; the isolates share the same molecular features in nucleotides and have characteristic amino acid signatures, i.e., 2 sites in the nucleoprotein and 3 sites in the glycoprotein, that are distinct from virus isolates from dogs in the same region. We conclude that rabies in Chinese ferret badgers has formed an independent transmission cycle and ferret badgers may serve as another important rabies reservoir independent of dog rabies in China.
文摘Vascular wilt disease caused by Foe (Fusarium oxysporum f. sp. elaeidis) invades the host xylem and causes a devastating disease of oil palm in west and central Africa. This disease has not been reported in Southeast Asia, in spite of long term importation for breeding purposes of African seed and pollen, shown in this laboratory at the University of Bath to be contaminated with Foe disease epidemiology was recently studied in plantations in Ghana. Infection mainly occurred in clusters, implying root-root transmission rather than aerial spread by spores. Molecular diagnostic tools has being developed for: (1) rapid detection and quantification of Foe in plant tissue, soil, seed and pollen for quarantine purposes in order to prevent transcontinental spread of Foe; and (2) to test efficacy of putative disease resistant or tolerant palm genotypes. We have investigated the possibility of Foe-suppressive soils in Malaysia in order to explain the non-appearance of this vascular disease there and possibly to reveal other potential biocontrol agents. The explanation as to why Malaysia has not yet attained the disease is likely to revolve around the soil properties, in particular the microflora. This review reported that greater disease severity based on visual symptoms occurred in autoclaved soils and compost than in untreated soils when oil palm seedlings artificially infected with Foe.