Potential targets by pentacyclic triterpenoids from Callicarpa farinosa against methicillin-resistant and sensitive Staphylococcus aureus.

The evolution of antibiotic resistance in Staphylococcus aureus showed that there is no long-lasting remedy against this pathogen. The limited number of antibacterial classes and the common occurrence of cross-resistance within and between classes reinforce the urgent need to discover new compounds targeting novel cellular functions not yet targeted by currently used drugs. One of the experimental approaches used to discover novel antibacterials and their in vitro targets is natural product screening.

Transcriptional profiles of the response of methicillin-resistant Staphylococcus aureus to pentacyclic triterpenoids.

Staphylococcus aureus is an important human pathogen in both hospital and the community that has demonstrated resistance to all currently available antibiotics over the last two decades. Multidrug-resistant isolates of methicillin-resistant S. aureus (MRSA) exhibiting decreased susceptibilities to glycopeptides has also emerged, representing a crucial challenge for antimicrobial therapy and infection control.

Identification, by gene expression profiling analysis, of novel gene targets in Staphylococcus aureus treated with betulinaldehyde.

Staphylococcus aureus has become a serious concern in hospitals and community due to rapid adaptation to existing antimicrobial agents. Betulinaldehyde [3β-hydroxy-20(29)-lupen-28-al (BE)] belongs to pentacyclic triterpenoids that are based on a 30-carbon skeleton comprising four six-membered rings and one five-membered ring. In a preliminary study, BE exhibited antimicrobial activity against reference strains of methicillin-resistant and methicillin-sensitive S.

Synergistic antimicrobial activity between pentacyclic triterpenoids and antibiotics against Staphylococcus aureus strains.

Background: There has been considerable effort to discover plant-derived antibacterials against methicillin-resistant strains of Staphylococcus aureus (MRSA) which have developed resistance to most existing antibiotics, including the last line of defence, vancomycin. Pentacyclic triterpenoid, a biologically diverse plant-derived natural product, has been reported to show anti-staphylococcal activities. The objective of this study is to evaluate the interaction between three pentacyclic triterpenoid and standard antibiotics (methicillin and vancomycin) against reference strains of Staphylococcus aureus.

High Helicobacter pylori resistance to metronidazole but zero or low resistance to clarithromycin, levofloxacin, and other antibiotics in Malaysia.

Objective: Bacterial resistance to antibiotics is the single most important determinant of treatment success. The objective of this study was to determine the prevalence of Helicobacter pylori resistance to clarithromycin, amoxicillin, metronidazole, tetracycline, levofloxacin, rifabutin, and furazolidone in our local bacterial strains.

Methods: Samples from consecutive ninety patients were obtained for culture and sensitivity testing.

Resistance to extended-spectrum beta-lactams by the emergence of SHV-12 and the loss of OmpK35 in Klebsiella pneumoniae and Escherichia coli in Malaysia.

Background And Purpose: In addition to beta-lactamase production, loss of porins confers resistance to extended-spectrum beta-lactams in Klebsiella pneumoniae and Escherichia coli infection. This study describes the detection of SHV-12 extended-spectrum beta-lactamase (ESBL) subtype and the loss of OmpK35 porin in 4 strains of K. pneumoniae and E.

Detection and characterization of class 1 integrons among carbapenem-resistant isolates of Acinetobacter spp. in Malaysia.

Background And Purpose: To detect and characterize class 1 integrons among carbapenem-resistant strains of Acinetobacter spp. at University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia.

Methods: Thirty nine carbapenem-resistant Acinetobacter strains were obtained from UMMC from August 2003 to March 2004 and analyzed for the presence of bla(IMP) genes and class 1 integrons.

Expression analysis of adherence-associated genes in pneumococcal clinical isolates during adherence to human respiratory epithelial cells (in vitro) by real-time PCR.

Pneumococcal virulence determinants have been extensively studied but molecular evidence on virulence gene expression pattern is still lacking. We undertook this study to analyze the regulation pattern of adherence-associated genes; psaA, pspC, cbpG, including ply of serotypes 1, 7F, 19F and 23F clinical isolates during the bacterial adherence to human lung epithelial cells (in vitro), by real-time PCR. We were able to harvest the bacterial RNA (0.

Detection of pbp2b and ermB genes in clinical isolates of Streptococcus pneumoniae.

Background: Streptococcus pneumoniae is a major human pathogen. The emergence of penicillin resistant strains since the 1970s has been life threatening and the evolution of the bacteria have enabled itself to develop resistance to many other antibiotics such as the macrolides and the fluoroquinolones. This study aims to characterize S.

Rapid detection of ESBL-producing Klebsiella pneumoniae in blood cultures by fluorescent in-situ hybridization.

Multi-resistant Enterobacteriaceae pose a serious threat of hospital acquired infections and their rapid identification is important for better clinical outcome. This study describes the rapid identification of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae of the sulphydryl variable-type by fluorescent in-situ hybridization. The method which rapidly identifies the target genes within 1 h could be a potentially rapid bacterial diagnostic tool.

Evaluation of the monoclonal stool antigen test for Helicobacter pylori in an Asian population with dyspepsia.

Objective: Although well established in the West, stool antigen tests (SAT) are not widely used in Asia. Data on the accuracy of this test in Asia is sparse and, to date, there have been no studies looking at the more refined monoclonal SAT. The aim of this study is to validate the diagnostic accuracy of a stool antigen test, Hp STAR, for the detection of Helicobacter pylori.

Extended-spectrum beta-lactam resistance due to AmpC hyperproduction and CMY-2 coupled with the loss of OMPK35 in Malaysian strains of Escherichia coli and Klebsiella pneumoniae.

In this report, we describe the detection of AmpC and CMY-2 beta-lactamases with the loss of OmpK35 porin among seven sporadic strains of ceftazidime-resistant Klebsiella pneumoniae and ceftazidime-resistant Escherichia coli. Cefoxitin, which was used as a marker of resistance toward 7-alpha-methoxy-cephalosporins, exhibited high minimum inhibitory concentration (MIC) values ranging between 128 microg/ml and >256 microg/ml in all the strains. The presence of hyperproducing AmpC enzymes was indicated by the positive three-dimensional test.

Evaluation of the routine use of the anaerobic bottle when using the BACTEC blood culture system.

The established practice of sending blood cultures in an aerobic-anaerobic pair of bottles has been questioned in recent years, and this study was conducted to evaluate the routine use of an anaerobic bottle in the BACTEC blood culture set at the University of Malaya Medical Centre, Kuala Lumpur, from January to December 2004. A total of 11,663 paired blood culture sets were received, of which 3326 were from pediatric patients and 8337 were from adult patients. The overall positive isolation rate was 15%; the positive isolation rate on excluding the anaerobic bottles was 13%.

Etiology of blood culture isolates among patients in a multidisciplinary teaching hospital in Kuala Lumpur.

Background And Purpose: Bloodstream infections are an important cause of morbidity and mortality among hospitalized patients and the surveillance of etiological agents in these infections is important for their prevention and treatment. Data on common organisms isolated from blood cultures from Malaysia are limited, and our aim was to identify the common bloodstream isolates in hospitalized patients at the University of Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia.

Methods: A retrospective analysis was conducted over a 1-year period from January to December 2004 by reviewing laboratory reports of patients from the UMMC.

HUITAI rapid urease test: a new ultra-rapid biopsy urease test for the diagnosis of Helicobacter pylori infection.

Background: The gastric biopsy urease test is an accurate and robust diagnostic test for Helicobacter pylori infection. Large endoscopy units use their own homemade unbuffered ultra-rapid urease test for diagnosis of H. pylori infection but several commercial rapid urease tests are available.

Childhood invasive pneumococcal disease: a hospital-based study from Malaysia.

Aim: New conjugate vaccine for Streptococcus pneumoniae has been introduced in Malaysia recently. Information on infection due to S. pneumoniae in Malaysian children is scarce.

Detection of mecA and ermA genes and simultaneous identification of Staphylococcus aureus using triplex real-time PCR from Malaysian S. aureus strain collections.

A triplex real-time polymerase chain reaction (PCR) assay was used for the simultaneous detection of mecA (methicillin resistance), ermA (erythromycin resistance) and femA (Staphylococcus aureus identification) genes in a single assay. Among 93 clinical S. aureus hospital isolates, there were 48 methicillin-resistant S.

Ethnicity and H. pylori as risk factors for gastric cancer in Malaysia: A prospective case control study.

Objective: To determine the risk factors for gastric cancer (GCA), with particular emphasis on ethnicity in our multiracial population.

Methods: A prospective case control study with ratio of cancer:controls of 1:2. Diagnosis of H.

Detection of methicillin- and aminoglycoside-resistant genes and simultaneous identification of S. aureus using triplex real-time PCR Taqman assay.

In this study we describe a triplex real-time PCR assay that enables the identification of S. aureus and detection of two important antibiotic resistant genes simultaneously using real-time PCR technology in a single assay. In this triplex real-time PCR assay, the mecA (methicillin resistant), femA (species specific S.

Simultaneous species identification and detection of methicillin resistance in staphylococci using triplex real-time PCR assay.

For rapid identification of methicillin-resistant Staphylococcus aureus, molecular methods are generally targeting mecA and species-specific genes. Sa442 DNA fragment is a popular species-specific target. However, recently, there have been few reports on S.

beta-Lactam resistance phenotype determination in Escherichia coli isolates from University Malaya Medical Centre.

beta-Lactamases have been identified as the major cause of antimicrobial resistance to beta-lactam antibiotics in Escherichia coli. The activities of ampicillin-sulbactam and amoxicillin-clavulanate as well as a range of beta-lactam antibiotics were studied with 87 clinical E. coli isolates from patients of the University Malaya Medical Center using the disc diffusion technique.

Comparison of susceptibility test methods to detect penicillin susceptibility in Streptococcus pneumoniae isolates.

The increasing prevalence of penicillin-resistant Streptococuus pneumoniae urges for fast and accurate susceptibility testing methods. This study evaluated the comparability of three commonly used techniques; disk diffusion, E-test and agar dilution, to detect penicillin susceptibility in clinical isolates of S. pneumoniae.

High prevalence of antimicrobial resistance among clinical Streptococcus pneumoniae isolates in Asia (an ANSORP study).

A total of 685 clinical Streptococcus pneumoniae isolates from patients with pneumococcal diseases were collected from 14 centers in 11 Asian countries from January 2000 to June 2001. The in vitro susceptibilities of the isolates to 14 antimicrobial agents were determined by the broth microdilution test. Among the isolates tested, 483 (52.