CD47 and CD36 expressions in the placenta of mothers with chorioamnionitis.

INTRODUCTION: Chorioamnionitis is the inflammation of the placenta and is histologically defined as the presence of neutrophilic infiltration into the chorio-amnion membrane with and without involvement of the umbilical cord. Currently, the inflammatory mediators involved in the eliciting of inflammatory response is still largely under investigation. CD47 and CD36 are pro-inflammatory molecules that are still under investigation. The aim of this study was to determine the expressions of CD47 and CD36 in the placenta of mothers with chorioamnionitis. MATERIALS AND METHODS: This was a cross-sectional study, involving a total of 100 cases that comprised of acute subchorionitis (stage I, n=20), acute chorioamnionitis (stage II, n=20), acute necrotising chorioamnionitis (stage III, n=20) and non-chorioamnionitis placenta as control (n=40). All tissue blocks were retrieved from the archived pathology record over a period of 4 years. CD36 and CD47 immunohistochemistry were performed on all cases and their expression in various cell types on the placenta were analysed. RESULTS: CD36 was expressed only on the foetal vascular endothelial cells. Interestingly, CD47 showed positive staining on the neutrophils and its expression was significantly different between maternal inflammatory response stage II chorioamnionitis (n=13/20, p<0.001) with stage I and stage III chorioamnionitis. DISCUSSION: Our study showed CD47 was expressed in the neutrophils and it was associated with poorer perinatal outcomes and it may have a role in the pathogenesis of chorioamnionitis.

Establishing and managing a periodontal biobank for research: the sharing of experience.

Periodontal bio-repositories, which allow banking of clinically validated human data and biological samples, provide an opportunity to derive biomarkers for periodontal diagnosis, prognosis and therapeutic activities which are expected to improve patient management. This article presents the establishing of the Malaysian Periodontal Database and Biobank System (MPDBS) which was initiated in 2011 with the aim to facilitate periodontal research. Partnerships were established with collaborating centres. Policies on specimen access, authorship and acknowledgement policies were agreed upon by all participating centres before the initiation of the periodontal biobank. Ethical approval for the collection of samples and data were obtained from institutional ethics review boards. A broad-based approach for informed consent was used, which covered areas related to quality of life impacts, genetics and molecular aspects of periodontal disease. Sample collection and processing was performed using a standardized protocol. Biobanking resources such as equipment and freezers were shared with the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS). In the development of the MPDBS, challenges that were previously faced by the MOCDTBS were considered. Future challenges in terms of ethical and legal issues will be faced when international collaborations necessitate the transportation of specimens across borders.

A rapid colorimetric screening method for vanillic acid and vanillin-producing bacterial strains.

AIM: To isolate a bacterial strain capable of biotransforming ferulic acid, a major component of lignin, into vanillin and vanillic acid by a rapid colorimetric screening method. METHODS AND RESULTS: For the production of vanillin, a natural aroma compound, we attempted to isolate a potential strain using a simple screening method based on pH change resulting from the degradation of ferulic acid. The strain Pseudomonas sp. AZ10 UPM exhibited a significant result because of colour changes observed on the assay plate on day 1 with a high intensity of yellow colour. The biotransformation of ferulic acid into vanillic acid by the AZ10 strain provided the yield (Yp/s ) and productivity (Pr ) of 1·08 mg mg(-1) and 53·1 mg L(-1) h(-1) , respectively. In fact, new investigations regarding lignin degradation revealed that the strain was not able to produce vanillin and vanillic acid directly from lignin; however, partially digested lignin by mixed enzymatic treatment allowed the strain to produce 30·7 mg l(-1) and 1·94 mg l(-1) of vanillic acid and biovanillin, respectively. CONCLUSIONS: (i) The rapid colorimetric screening method allowed the isolation of a biovanillin producer using ferulic acid as the sole carbon source. (ii) Enzymatic treatment partially digested lignin, which could then be utilized by the strain to produce biovanillin and vanillic acid. SIGNIFICANCE AND IMPACT OF THE STUDY: To the best of our knowledge, this is the first study reporting the use of a rapid colorimetric screening method for bacterial strains producing vanillin and vanillic acid from ferulic acid.

Optimization of Growth medium for Efficient Cultivation of Lactobacillus salivarius i 24 using Response Surface Method

Production of Lactobacillus salivarius i 24, a probiotic strain for chicken, was studied in batch fermentation using 500 mL Erlenmeyer flask. Response surface method (RSM) was used to optimize the medium for efficient cultivation of the bacterium. The factors investigated were yeast extract, glucose and initial culture pH. A polynomial regression model with cubic and quartic terms was used for the analysis of the experimental data. Estimated optimal conditions of the factors for growth of L. salivarius i 24 were; 3.32 % (w/v) glucose, 4.31 % (w/v) yeast extract and initial culture pH of 6.10.

Prevalence of Staphylococcus aureus carriage by young Malaysian footballers during indoor training.

BACKGROUND: Research has shown that athletes are carriers of Staphylococcus aureus during physical activity. OBJECTIVE: To estimate the mean total plate count of S aureus carried by footballers before and after training at an indoor venue. METHODS: Forty Malay and 20 Indian students volunteered to participate. There was also a control group consisting of 40 Malay and 20 Indian students who were not active. The experimental group were active footballers who had played at school or club level. The subjects were healthy and free of skin infection. The experiment was divided into three sessions, with 20 subjects present at each. At each session, the subjects trained for one hour. Swabs were taken from the skin, nose, and ear before and after training. For the control group, swabs were taken only once from the skin, nose, and ear. The swabs were subjected to biochemical tests and then streaked and cultured aerobically in Baird Parker agar plates for 24 hours at 37 degrees C. Black colonies with a clear zone were presumed to be S aureus, and the mean total plate count of the colonies was estimated. Gram staining, catalase, coagulase slide, coagulase tube, acetoin production, o-nitrophenyl beta-D-galactopyranoside (ONPG), and mannitol fermentation tests were used to confirm the colonies as S aureus. A haemolysin test was conducted with human blood to confirm haemolytic activity. RESULTS: All subjects in the experimental group were carrying S aureus both before and after training. The estimated mean total counts of colonies from the skin, ear, and nose for the Malays before training were 33, 71, and 312 respectively. Counts after training were 21, 44, and 452 respectively. The results for the Indians were 72, 80, and 309 respectively before training and 55, 200, and 466 respectively after training. The positive results for Gram staining, catalase, coagulase slide, coagulase tube, acetoin production, ONPG, and mannitol fermentation tests were 100%, 96%, 95%, 95%, 93%, 93%, and 90% respectively. All subjects in the control group were also carrying S aureus. CONCLUSIONS: All of the players were carriers of S aureus during training. The decrease in total count from the skin for both races may be due to lysozyme activity lysing the bacterial cells. Contamination of the environment with these bacteria may have increased the estimated total plate count in the nose. The experimental group face a higher risk of infection because of lower immunity during training and higher rate of injuries compared with the control group.

Prevalence of Listeria spp and Listeria monocytogenes in meat and fermented fish in Malaysia.

Fermented fish and meat samples were purchased from supermarket and wet market for microbiological analysis of Listeria species and Listeria monocytogenes contamination. Listeria species were isolated from 17 (73.9%) of 23 samples of imported frozen beef, 10 (43.5%) of the 23 samples of local beef and 14 (56%) of the 25 samples of fermented fish from wet market. Listeria monocytogenes occurred in 15 (75%) of the frozen beef samples, 6 (30.4%) of the 23 samples of local meat and 3 (12%) of the 25 samples from fermented fish. Listeria species was not isolated from any of the 23 samples of imported frozen beef from supermarket and from the 5 samples of buffalo meat examined. This highlights the possibility of Listeria spp or L. monocytogenes to persist in meat and fermented fish in wet market and raises the problem of illness due to the handling and consumption of Listeria-contaminated meat or fermented fish are likely as evidence by the high contamination rates of samples sold at the wet market.

Detection and molecular characterization of the zot gene in Vibrio cholerae and V. alginolyticus isolates.

A total of 11 Vibrio cholerae isolates from 1996-1998 outbreaks in Malaysia and 4 V. alginolyticus were analyzed. Isolates were characterized by polymerase chain reaction (PCR) and Southern hybridization for the presence of the gene encoding zonula occludens toxin (zot). Screening of zot gene by PCR revealed the presence of this gene in V. cholerae and V. alginolyticus. The zot gene from one V. cholerae Ogawa isolate that was cloned in a pCR 2.1 TOPO vector was sequenced. The sequences obtained were 99% homologous to the zot gene sequence from the Gene Bank.

Occurrence of the vanA and vanC2/C3 genes in Enterococcus species isolated from poultry sources in Malaysia.

Enterococcus species isolated from poultry sources were characterized for their resistance to antibiotics, plasmid content, presence of van genes and their diversity by randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). The results showed that all isolates were multi-resistance to the antibiotics tested. Ampicillin (15/70) followed by chloramphenicol (37/70) were the most active antibiotics tested against the Enterococcus spp. isolates, while the overall resistant rates against the other antibiotics were between 64.3% to 100%. All vancomycin-resistant E. faecalis, E. durans, E. hirae and E. faecium isolates tested by the disk diffusion assay were positive in PCR detection for presence of vanA gene. All E. casseliflavus isolates were positive for vanC2/C3 gene. However, none of the Enterococcus spp. isolates were positive for vanB and vanC1 genes. Plasmids ranging in sizes between 1.1 to ca. 35.8 MDa were detected in 38/70 of the Enterococcus isolates. When the genetic relationship among all isolates of the individual species were tested by RAPD-PCR, genetic differences detected suggested a high genetic polymorphisms of isolates in each individual species. Our results indicates that further epidemiological studies are necessary to elucidate the role of food animals as reservoir of VRE and the public health significance of infections caused by Enterococcus spp.

Detection of Vancomycin-Resistant Enterococcus Spp. (VRE) from Poultry.

Twenty-eight isolates of E. faecalis and 5 isolates of E. hirae were isolated from chicken samples obtained from markets in Sri Serdang, Selangor. They were tested for susceptibility to vancomycin and other antimicrobial agents. All of the isolates showed multiple resistance to the antibiotic tested. All Enterococcus spp. were resistant (100%) to ceftaxidime, cephalothin, erythromycin, gentamicin, kanamycin, nalidixic acid and streptomycin. Resistance was also observed to norfloxacin (97%), tetracycline (91%), penicillin (85%), bacitracin (82%), chloramphenicol (61%) and the least resistance was to ampicillin (27%). High prevalence to vancomycin resistance was detected among the E. faecalis (27of 28) and E. hirae (4 of 5) isolates. The multiple antibiotic resistance index ranging between 0.64 to 1.0 showed that all strains tested originated from high-risk contamination. Plasmid profile analysis of Enterococcus spp. revealed plasmid DNA bands ranging in size from 1.3 to 35.8 megadalton but some isolates were plasmidless. No correlation could be made between plasmid patterns and antibiotic resistance.

Plasmid-mediated streptomycin resistance of listeria monocytogenes.

A strain of streptomycin-resistant Listeria monocytogenes LM35 isolated from imported frozen beef was examined in this study. In conjugation studies, the L. monocytogenes LM35 strain harbouring two plasmids of 54, 3.0, 2.8 and 2.7 kilobase was used as the donor and streptomycin-sensitive and plasmidless L. monocytogenes LM65 and LM100 strains as the recipients. Streptomycin resistance was transferred to L. monocytogenes LM65 and LM100 strains at frequencies of 3.3 × 10(-8) and 1.2 × 10(-9) per input donor cells, respectively. In both occasions, we also observed the concomitant transfer of the donor's 54 kilobase plasmid. These results suggest that streptomycin resistance in L. monocytogenes LM35 was mediated by the 54 kilobase plasmid.

Human heat shock protein gene polymorphisms and sudden infant death syndrome.

Comparison of the frequency of occurrence of restriction fragment length polymorphisms in control human DNAs and DNAs from infants dying from sudden infant death syndrome has indicated no significant difference in the case of restriction fragment length polymorphisms associated with the heat shock protein genes hsp70 and hsp90. A highly significant difference was detected, however, in the case of the specific restriction fragment length polymorphisms detected by an hsp60 gene probe in MspI digests.

Hydrogen peroxide and sequence-specific DNA damage in human cells.

Exposure of HeLa cells in monolayer culture to increasing concentrations of exogenously added H2O2 causes damage to cellular DNA. When the DNA is subsequently isolated from the non-apoptotic cells remaining in such cultures, evidence was obtained to suggest that the DNA damage elicited in intact cells was non-random and that certain nucleotide sequences associated with, or related to, the genes for heat shock protein 60 and catalase were more susceptible to damage than others. In contrast, these particular sequences were not specifically susceptible to damage when naked human DNA was exposed directly to H2O2 in vitro. On an overall comparative basis, sequences in the genes encoding catalase, alpha-1 antitrypsin and beta-actin appear more vulnerable to H2O2 in vivo, than sequences in H-ras and the P53 gene which seem surprisingly resistant.