Helicobacter pylori infection is involved in several gastroduodenal diseases which can be cured by antimicrobial treatment. The aim of this study was to determine the prevalence of H. pylori infection and its bacterial resistance to clarithromycin, fluoroquinolones, and tetracycline in Brazzaville, Congo, by using molecular methods.
The accuracy of the conclusions from in vivo efficacy anti-malarial drug trials depends on distinguishing between recrudescences and re-infections which is accomplished by genotyping genes coding P. falciparum merozoite surface 1 (MSP1) and MSP2. However, the reliability of the PCR analysis depends on the genetic markers' allelic diversity and variant frequency. In this study the genetic diversity of the genes coding for MSP1 and MSP2 was obtained for P. falciparum parasites circulating in Yemen.
Yeasts are a convenient platform for many applications. They have been widely used as the expression hosts. There is a need to have a new yeast expression system to contribute the molecular cloning demands. Eight yeast isolates were screened from various environment sources and identified through ribosomal DNA (rDNA) Internal Transcribed Spacer (ITS). Full sequence of the rDNA ITS region for each isolate was BLASTed and phylogenetic study was constructed by using MEGA4. Among the isolates, isolate WB from 'ragi' (used to ferment carbohydrates) could be identified as a new species in order Saccharomycetales according to rDNA ITS region, morphology and biochemical tests. Isolate SO (from spoiled orange), RT (rotten tomato) and RG (different type of 'ragi') were identified as Pichia sp. Isolates R1 and R2, S4 and S5 (from the surrounding of a guava tree) were identified as Issatchenkia sp. and Hanseniaspora sp., respectively. Geneticin, 50 µg/mL, was determined to be the antibiotic marker for all isolates excepted for isolates RT and SO which used 500 µg/mL and 100 µg/mL Zeocin, respectively. Intra-extracellular proteins were screened for lipolytic activity at 30°C and 70°C. Thermostable lipase activity was detected in isolates RT and R1 with 0.6 U/mg and 0.1 U/mg, respectively. In conclusion, a new yeast-vector system for isolate WB can be developed by using phleomycin or geneticin as the drugs resistance marker. Moreover, strains RT and R1 can be investigated as a novel source of a thermostable lipase.
Despite the association of methicillin-susceptible S. aureus (MSSA) with several life-threatening diseases, relatively little is known about their clinical epidemiology in Malaysia. We characterized MSSA isolates (n=252) obtained from clinical and community (carriage) sources based on spa sequencing and multilocus sequence typing (MLST). The prevalence of several important virulence genes was determined to further define the molecular characteristics of MSSA clones circulating in Malaysia. Among the 142 clinical and 110 community-acquired MSSA isolates, 98 different spa types were identified, corresponding to 8 different spa clonal clusters (spa-CCs). In addition, MLST analysis revealed 22 sequence types (STs) with 5 singletons corresponding to 12 MLST-CCs. Interestingly, spa-CC084/085 (MLST-CC15) (p=0.038), spa-non-founder 2 (MLST-ST188) (p=0.002), and spa-CC127 (MLST-CC1) (p=0.049) were identified significantly more often among clinical isolates. spa-CC3204 (MLST-CC121) (p=0.02) and spa-CC015 (MLST-CC45) (p=0.0002) were more common among community isolates. Five dominant MLST-CCs (CC8, CC121, CC1, CC45, and CC5) having clear counterparts among the major MRSA clones were also identified in this study. While the MSSA strains are usually genetically heterogeneous, a relatively high frequency (19/7.5%) of ST188 (t189) strains was found, with 57.8% of these strains carrying the Panton-Valentine leukocidin (PVL). Analysis of additional virulence genes showed a frequency of 36.5% and 36.9% for seg and sei and 0.8% and 6.3% for etb and tst genes, respectively. Arginine catabolic mobile element (ACME) was detected in 4 community isolates only. These represent the first isolates harbouring this gene in an Asian region. In conclusion, MSSA from the Malaysian community and their clinical counterparts are genetically diverse, but certain clones occur more often among clinical isolates than among carriage isolates and vice versa.
The aim of the present study was to assess and compare the antimicrobial susceptibility pattern against a panel of antibiotics and molecular and methicillin resistance-associated genotypes of 120 carriage S. aureus isolates previously isolated from a student population at two isolation events within a one-month interval. The antibiotic susceptibility of isolates was determined using the Kirby-Bauer disc-diffusion method (cefoxitin by Etest). The MRSA was screened using polymerase chain reaction for the presence of the mecA gene. The mecA-positive isolates were subjected to staphylococcal cassette chromosome (SCC) mec typing, multilocus sequence typing (MLST) and eBURST analysis. All isolates were characterized for the presence of the Panton-Valentine leukocidin (PVL) gene, an enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) pattern and the spa type. For the two occasions where S. aureus was isolated, the highest frequency of resistance was observed for penicillin (70% and 65%, respectively), with a lower rate against erythromycin and tetracycline (<12%). All isolates were susceptible to ciprofloxacin and gentamycin. As for methicillin resistance, eight isolates had minimum inhibitory concentrations (MIC) of resistant categories, but 10 isolates (8.33%) were positive for the mecA gene. The mecA-positive isolates belonged to SCCmec types I (n=9) and V (n=1). MLST was resolved for only three MRSAs, ST508 (n=1), ST88 (n=1) and ST96 (n=1). The results of the eBURST analysis showed that the MRSA isolates analyzed in the present study were potentially related to MRSA identified in other countries. Approximately half of the persistent S. aureus carriers harbored S. aureus of a similar spa type in the respective individuals during both isolation events. A persistent antimicrobial pattern and limited distinct MRSAs were observed over the short study period. The latter frequently exhibited SCCmec type I, commonly associated with hospital-acquired (HA) characteristics, but further delineation is needed to justify the origins of these bacteria.
Non-typhoidal Salmonella (NTS) bacteremia is a significant cause of morbidity and mortality worldwide. It is considered to be an emerging and neglected tropical disease in Africa. We studied this in two tertiary hospitals-Al Farwaniya and Al Amiri-in Kuwait, a subtropical country, from April 2013-May 2016. NTS bacteremia was present in 30 of 53,860 (0.75%) and 31 of 290,36 (1.33%) blood cultures in the two hospitals respectively. In Al Farwaniya hospital, one-third of the patients were from some tropical developing countries of Asia. About 66% of all patients (40/61) had diarrhea, and of these, 65% had the corresponding blood serovar isolated from stool culture. A few patients had Salmonella cultured from urine. Patients were either young or old. Most of the patients had co-morbidities affecting the immune system. Two patients each died in both hospitals. The number of different serovars cultured in each hospital was 13, and most infections were due to S. Enteritidis (all sequence type [ST]) 11) and S. Typhimurium (all ST19) except in a subgroup of expatriate patients from tropical developing countries in Al Farwaniya hospital. About a quarter of the isolates were multidrug-resistant. Most patients were treated with a cephalosporin with or without other antibiotics. S. Enteritidis and S. Typhimurium isolates were typed by pulsed field-gel electrophoresis (PFGE) and a selected number of isolates were whole-genome sequenced. Up to four different clades were present by PFGE in either species. Whole-genome sequenced isolates showed antibiotic-resistance genes that showed phenotypic correlation, and in some cases, phenotypes showed absence of specific genes. Whole-genome sequenced isolates showed presence of genes that contributed to blood-stream infection. Phylogeny by core genome analysis showed a close relationship with S. Typhimurium and S. Enteritidis from other parts of the world. The uniqueness of our study included the finding of a low prevalence of infection, mortality and multidrug-resistance, a relatively high prevalence of gastrointestinal infection in patients, and the characterization of selected isolates of S. Typhimurium and S. Enteritidis serovars by whole-genome sequencing that shed light on phylogeny, virulence and resistance. Similarities with studies from developing countries especially Africa included infection in patients with co-morbidities affecting the immune system, predominance of S. Typhimurium and S. Enteritidis serovars and presence of drug-resistance in isolates.
Capsular serotypes K1 and K2 of Klebsiella pneumoniae are thought to the major virulence determinants responsible for liver abscess. The intestine is one of the major reservoirs of K. pneumoniae, and epidemiological studies have suggested that the majority of K. pneumoniae infections are preceded by colonization of the gastrointestinal tract. The possibility of fecal-oral transmission in liver abscess has been raised on the basis of molecular typing of isolates. Data on the serotype distribution of K. pneumoniae in stool samples from healthy individuals has not been previously reported. This study investigated the seroepidemiology of K. pneumoniae isolates from the intestinal tract of healthy Chinese in Asian countries. Stool specimens from healthy adult Chinese residents of Taiwan, Japan, Hong Kong, China, Thailand, Malaysia, Singapore, and Vietnam were collected from August 2004 to August 2010 for analysis.
In addition to being a human pathogen, Staphylococcus aureus causes an array of infections in economically important livestock animals, particularly pigs. In Asia, there have been few reports on livestock-associated meticillin-resistant S. aureus (LA-MRSA), mostly from developed countries, with very few data available from resource-limited countries, not because of low prevalence but probably due to a shortage of diagnostic facilities. Unlike the wide spread of sequence type 398 (ST398) LA-MRSA in European countries and North America, ST9 predominates in most Asian countries. The prevalence of LA-MRSA among pigs in Asian countries varied widely (0.9-42.5%). The prevalence may vary by geographic location, age of pigs and sampling methodologies. Among pig farmers, the prevalence of nasal MRSA colonisation varied from 5.5% in Malaysia to 15% in China and 19.2% in Taiwan. Although most LA-MRSA isolates in Asia are of the same ST, molecular characteristics are not all the same. Dominant isolates in China were characterised as spa type t899-SCCmec III and t899-SCCmec IVb or V for isolates in Hong Kong, and t899-untypeable SCCmec for Taiwan. Dominant isolates in Malaysia were spa type t4358-SCCmec V and t337-SCCmec IX for isolates in Thailand. In addition, MRSA ST221 was reported in Japan and MRSA ST398 was isolated from commercial pigs in South Korea. Attention should be paid because pigs could become an important reservoir for MRSA and spread them to humans, as observed in many countries. There is a potential risk from the livestock reservoir to community and hospitals.
Salmonella enterica serovar Paratyphi B (S. Paratyphi B) is a major foodborne pathogen distributed all over the world. However, little is known about the antibiotic resistance, genetic relatedness and virulence profile of S. Paratyphi B isolated from leafy vegetables and the processing environment in Malaysia. In this study, 6 S. Paratyphi B isolates were recovered from different vegetables and drain water of processing areas obtained from fresh food markets in Malaysia. The isolates were characterized by antibiogram, Pulsed-field gel electrophoresis (PFGE) and virulence genes. Antibiotic susceptibility test showed that 3 of the isolates were resistant to the antibiotics. These include S. Paratyphi B SP251 isolate, which was resistant to chloramphenicol, ampicillin, sulfonamides and streptomycin; Isolate SP246 which was resistant to chloramphenicol, sulfonamides and streptomycin and Isolate SP235 showing resistance to nalidixic acid only. PFGE subtyped the 6 S. Paratyphi B isolates into 6 distinct XbaI-pulsotypes, with a wide range of genetic similarity (0.55 to 0.9). The isolates from different sources and fresh food markets location were genetically diverse. Thirteen (tolC, orgA, spaN, prgH, sipB, invA, pefA, sofB, msgA, cdtB, pagC, spiA and spvB) out of the 17 virulence genes tested were found in all of the S. Paratyphi B isolates. Another gene (lpfC), was found only in one isolate (SP051). None of the isolates possessed sifA, sitC and ironN genes. In summary, this study provides unique information on antibiotic resistance, genetic relatedness, and virulotyping of S. Paratyphi B isolated from leafy vegetables and processing environment.
Nipah virus (NiV) is a highly pathogenic paramyxovirus that causes fatal encephalitis in humans. The initial outbreak of NiV infection occurred in Malaysia and Singapore in 1998-1999; relatively small, sporadic outbreaks among humans have occurred in Bangladesh since 2001. We characterized the complete genomic sequences of identical NiV isolates from 2 patients in 2008 and partial genomic sequences of throat swab samples from 3 patients in 2010, all from Bangladesh. All sequences from patients in Bangladesh comprised a distinct genetic group. However, the detection of 3 genetically distinct sequences from patients in the districts of Faridpur and Gopalganj indicated multiple co-circulating lineages in a localized region over a short time (January-March 2010). Sequence comparisons between the open reading frames of all available NiV genes led us to propose a standardized protocol for genotyping NiV; this protcol provides a simple and accurate way to classify current and future NiV sequences.
The energy-salvaging capacity of the gut microbiota from dietary ingredients has been proposed as a contributing factor for the development of obesity. This knowledge generated interest in the use of non-digestible dietary ingredients such as prebiotics to manipulate host energy homeostasis. In the present study, the in vitro response of obese human faecal microbiota to novel oligosaccharides was investigated. Dextrans of various molecular weights and degrees of branching were fermented with the faecal microbiota of healthy obese adults in pH-controlled batch cultures. Changes in bacterial populations were monitored using fluorescent in situ hybridisation and SCFA concentrations were analysed by HPLC. The rate of gas production and total volume of gas produced were also determined. In general, the novel dextrans and inulin increased the counts of bifidobacteria. Some of the dextrans were able to alter the composition of the obese human microbiota by increasing the counts of Bacteroides-Prevotella and decreasing those of Faecalibacterium prausnitzii and Ruminococcus bromii/R. flavefaciens. Considerable increases in SCFA concentrations were observed in response to all substrates. Gas production rates were similar during the fermentation of all dextrans, but significantly lower than those during the fermentation of inulin. Lower total gas production and shorter time to attain maximal gas production were observed during the fermentation of the linear 1 kDa dextran than during the fermentation of the other dextrans. The efficacy of bifidobacteria to ferment dextrans relied on the molecular weight and not on the degree of branching. In conclusion, there are no differences in the profiles between the obese and lean human faecal fermentations of dextrans.
Japanese encephalitis virus (JEV) genotype V reemerged in Asia (China) in 2009 after a 57-year hiatus from the continent, thereby emphasizing a need to increase regional surveillance efforts. Genotypic characterization was performed on 19 JEV-positive mosquito pools (18 pools of Culex tritaeniorhynchus and 1 pool of Cx. bitaeniorhynchus) from a total of 64 positive pools collected from geographically different locations throughout the Republic of Korea (ROK) during 2008 and 2010.
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common nosocomial pathogens, causing mild to severe infections. This study aimed to determine the genotypic and phenotypic characteristics of clinical MRSA isolates collected from a teaching hospital from 2014 - 2015. These isolates were genotyped by multilocus sequence typing, staphylococcal cassette chromosomal mec (SCCmec) typing, virulence genes detection, and pulsed-field gel electrophoresis; they were phenotyped based on their antibiotics susceptibility profiles. The most prevalent sequence type was ST22. ST3547 was identified from a blood isolate from 2015. Three SCCmec types (III in 26.26%, IV in 70.71%, and V in 3.03% isolates) were detected. Agr type I, II, and III were also detected among the isolates. The most prevalent virulence genes found were hemolysin (100%) and intracellular adhesion (91.9%). At least one staphylococcal enterotoxin was detected in 83 (83.8%) isolates. All the isolates were susceptible to vancomycin (minimum inhibitory concentration ≤ 2 μg/mL). Statistical analysis revealed a significant increase in hypertension (p = 0.035), dyslipidemia and obesity (p = 0.046), and previous exposure to any quinolone (p = 0.010) cases over the two-year period. The emergence and circulation of community-associated MRSA variants were observed in our hospital.
Introduction: Hepatitis C virus (HCV) infection is a serious health problem. It is a major contributor to end-stage liver disease. Worldwide, 1-8% of all pregnant women were infected. Women with viral hepatitis may be at an increased risk of pregnancy complications. There are several obstetrics intervention acts as risk factors, which are specific to women pertaining the HCV infection; anti-D immunoglobulin (Ig) therapy may be one of them. Our objectives were to estimate the prevalence of HCV antibodies (anti-HCV), RNA, and genotype distribution among women with anti-D Ig therapy. Materials and methods: A cross sectional study was conducted. A sample of 154 Rhesus negative (Rh - ve) pregnant women regardless of the anti-D Ig therapy was collected. Anti-HCV were tested using third generation enzyme immunoassay (EIA-3) and immunoblot assay (Lia Tek-111), subsequently. In addition, 89 serum samples were subjected to molecular analysis using RT-PCR and DNA enzyme immunoassay (DEIA) method for the detection of HCV-RNA and genotypes. Results: Anti-HCV, and HCV-RNA seroprevalence were significantly higher (17.1, 35.5%) among women with anti-D Ig than their counter group (6.4, 13.16%), p = .038, .018, respectively. Significant direct positive dose response correlation (r = 0.78, p = .005) had been seen between number of anti-D Ig therapy and anti-HCV seropositive rate. Anti-D Ig therapy act as a risk factor (odds ratio (OR) = 3.01, 95%CI: 1.01-8.9) especially from the third dose onward. Women with anti-D Ig therapy were at higher risk (3.6 times more) of positive HCV-RNA (OR =3.6, 95%CI =1.19-10.837). Genotype HCV-1b showed higher prevalent (52.9%) among the recipients of anti-D Ig therapy while genotype HCV-3a (6.6%) was the lowest. Conclusions: Our study showed that Anti-D immunoglobulin therapy acts as a risk factor for acquiring HCV infection. Screening for HCV should be recommended for all recipients of anti-D Ig. Not only HCV antibodies but HCV-RNA detection being recommended for the diagnosis of HCV infection. A brief rational: Pregnant women with HCV infection are at risk of adverse obstetric outcome. Anti-D Ig therapy may be a risk factor for HCV infection. Hence, we conducted a cross sectional study with the objectives to estimate the prevalence of HCV antibodies (anti-HCV), RNA, and genotype distribution among women with anti-D Ig therapy. We found that anti-HCV and HCV-RNA seroprevalence were significantly higher in women with anti-D Ig. In addition, women with anti-D Ig therapy were 3.6 times more at risk of positive HCV-RNA with genotype HCV-1b showed higher prevalence. Therefore, anti-D Ig therapy is a risk factor for acquiring HCV infection and we recommend screening for HCV for all recipients of anti-D Ig. In addition, the diagnosis of HCV infection, should be made with HCV antibodies and HCV-RNA detection.
Methicillin-resistant Staphylococcus aureus (MRSA) is known to cause nosocomial infections and is now becoming an emerging problem in veterinary medicine. The objective of the study was to determine the presence of MRSA in 100 cats and dogs sampled between November 2007 and April 2008 at the University Veterinary Hospital, Universiti Putra Malaysia. MRSA was detected in 8% of pets sampled. Ten percent (5/50) and 6% (3/50) of the isolates were from dogs and cats, respectively. All MRSA isolates possessed the mecA gene and were found to be resistant to at least three antimicrobials with a minimum of Oxacillin MIC of 8 μg/mL. One isolate (CT04) had an extremely high MIC of >256 μg/mL. The MLST type ST59 found in this study have been reported earlier from Singapore and other countries as a strain from animal and community-associated MRSA respectively. Pulsed-field gel electrophoresis revealed five pulsotypes. Two isolates from cats (CT27 and CT33) and three isolates from dogs (DG16, DG20, and DG49) were respectively assigned to pulsotypes B and D. The study suggests that cats and dogs in Malaysia are potential reservoirs for MRSA.