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The prevalence of methicillin resistant Staphylococcus aureus (MRSA) and methicillin sensitive Staphylococcus aureus (MSSA) carriage among poultry and poultry farmers in Malaysia is largely unknown. In the current investigation, chickens and chicken farmers from 30 chicken farms were screened for MRSA and S. aureus carriage. The genetic characteristics of the isolates were determined through multi locus sequence typing (MLST), Staphylococcus protein A (spa) typing and virulent gene profiling. The outcome of the study showed lack of MRSA and extremely low S. aureus prevalence (n=7 of 503, 1.4%) among chicken flocks and the poultry farmers in Malaysia. Staphylococcus aureus isolates belonged to 4 sequence types (ST): ST97 (spa type t359), ST1179 (t359), ST 692 (t2247) and ST188 (t189). It can be concluded that MRSA/MSSA prevalence is very low among chicken and chicken farmers, human and chicken cross transmission of S. aureus does not seem to be a threat in Malaysia. [ABSTRACT FROM AUTHOR]

Laser-engineered net shaping, referred to as LENSTM process, is an additive manufacturing technique for building metallic parts, layer by layer, by direct deposition of metal powders in a melt pool created by a focused laser beam. The process involves rapid melting and solidification of a controlled amount of injected metal powders as a laser beam scans over each layer building the structure from the bottom to the top. Due to its unique capability to deposit precise amounts of powder material at a desired location, the LENSTM process finds potential application in rapid tooling, prototyping, precision repair work, and manufacture of complex, intricate components with varying compositions. The peak temperature and thermal cycle experienced by each layer influence the final mechanical properties and dimensional accuracy of the part. An understanding and quantitative knowledge of the peak temperature, melt pool dimensions, and thermal cycles experienced in the deposited layers are essential for a priori selection of the process parameters in LENSTM technique. It is important to ensure that the deposited layers have the desired dimensions, good interlayer bonding, and requisite mechanical properties. In an attempt to understand the process parameters to be used in achieving the desired nature of deposition, a three-dimensional model is developed based on finite element method to numerically simulate heat transfer phenomenon in LENSTM process considering deposition of SS316 powders on a substrate of the same material. The computed temperature profiles are first validated with experimental results reported in the literature. The influence of process parameters on peak temperature, thermal cycles, and melt pool dimensions are studied subsequently. The continuous movement of laser and synchronized activation of elements depicting addition of powder particles are incorporated through an externally written user subroutine and using the element deactivation and activation features in the commercial finite element software ABAQUS 6.7. A unique non-dimensional parameter specific to LENSTM process is defined considering the combined influence of process parameters and material properties. The non-dimensional parameter is further used to serve as a guideline for the selection of appropriate process parameters that can result in a steady melt pool dimension, thereby ensuring a target layer width with good interlayer bonding. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) from Malaysia were shown to possess staphylococcal cassette chromosome mec (SCC mec)-III and IIIA. Spa sequencing and multi-locus sequence typing (MLST) documented t037 and ST 239 (CC8) for 83.3% of the isolates. This confirms observations in several other Far Eastern countries and corroborates the epidemicity of this clone. [ABSTRACT FROM AUTHOR]

Competing Interests: There are no conflicts of interest.

Leptospirosis, a widespread zoonotic disease, is a public health problem, especially in major urban centres, and is mainly reported to be associated with rats. In Malaysia, focus has been primarily given to the Leptospira prevalence in rodents per se, but there is lack of information on the microhabitat structure of the outbreak areas. We aimed to determine the diversity of small mammal species, microhabitat types, and their prevalence of pathogenic Leptospira spp. in the outbreak areas, which were categorized as urban, semi-urban, and recreational forests. Sampling involved deploying 100 to 300 live traps at each study site. Kidney samples were extracted from selected individuals, for screening of pathogenic Leptospira spp. by PCR. Out of 537 individuals from 15 small mammal species captured, 4 species were recorded from urban, 13 from semi-urban, and 11 from recreational forest sites. From 389 individuals screened, 58 were tested positive for pathogenic Leptospira. Recreational forests recorded the highest prevalence with 19.4% (n = 93), followed by urban, 16.6% (n = 163) and semi-urban sites with 9.8% (n = 133). Seven rodent species were tested positive for pathogenic Leptospira from all areas. R. norvegicus was found to harbour the highest prevalence (66.7%) in urban, R. rattus (53.8%) in semi-urban, whereby M. whiteheadi (44.4%) in recreational forest sites. Microhabitat analysis revealed that rubbish quantity contributed especially strongly to a high prevalence of Leptospira. This study contributes to understanding of the host and microhabitat preferences of Leptospira, which is important in controlling the spread of this disease in human's landscapes.

Antibiotic resistance is a problem that continues to challenge the healthcare sector, especially in clinically significant pathogens like methicillin-resistant Staphylococcus aureus (MRSA). Herein is described the isolation and structure elucidation of a bioactive compound from Allium stipitatum with antimicrobial activity. Crude Allium stipitatum dichloromethane extract (ASDE) was subjected to systematic purification by chromatographic procedures to afford various bioactive fractions. A fraction that exhibited anti-MRSA activity (4 µg·mL -1 ) was further characterized to determine the structure. The structure of the compound was elucidated as 2-(methyldithio)pyridine-3-carbonitrile (2-Medpy-3-CN). The 2-Medpy-3-CN compound, which was screened for antimicrobial activity, exhibited minimum inhibitory concentrations (MICs) in the range of 0.5 to >64 µg·mL -1 for tested bacterial species and 0.25 to 2 µg·mL -1 for Candida spp. Further studies are important to confirm the drug target and mechanism of action.

The present study assessed the in vitro antibacterial and antibiofilm potential of hexane (ASHE) and dichloromethane (ASDE) extracts of Allium stipitatum (Persian shallot) against planktonic cells and biofilm structures of clinically significant antibiotic resistant pathogens, with a special emphasis on methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), and emerging pathogens, Acinetobacter baumannii and Stenotrophomonas maltophilia . Antibacterial activities were determined through disk diffusion, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), time-kill kinetics, and electron microscopy. Antibiofilm activity was assessed by XTT [2,3- bis (2-methoxy-4-nitro-5-sulfo-phenyl)-2H-tetrazolium-5-carboxanilide] reduction assay and by confocal laser scanning microscopy (CLSM). The zone of inhibition ranged from 13 to 33 mm, while the MICs and MBCs ranged from 16 to 1024 μ g mL -1 . Both ASHE and ASDE completely eradicated overnight cultures of the test microorganisms, including antibiotic resistant strains. Time-kill studies showed that the extracts were strongly bactericidal against planktonic cultures of S. aureus , MRSA, Acinetobacter baumannii, and S. maltophilia as early as 4 hours postinoculation (hpi). ASHE and ASDE were shown to inhibit preformed biofilms of the four biofilm phenotypes tested. Our results demonstrate the potential therapeutic application of ASHE and ASDE to inhibit the growth of gram-positive and gram-negative biofilms of clinical significance and warrant further investigation of the potential of A. stipitatum bulbs against biofilm-related drug resistance.

The in vivo antibacterial and burn wound healing potency of Persian shallot bulbs ( Allium stipitatum ) were explored in a mice burn model infected with methicillin-resistant Staphylococcus aureus (MRSA). Hexane (ASHE) and dichloromethane (ASDE) extracts were tested. Female BALB/c mice were inflicted with third-degree thermal injury followed by infection with MRSA. ASHE and ASDE formulated with simple ointment base (SOB) at concentrations of 1%, 2%, and 5% (w/w) were topically applied to burn wounds twice a day for 20 days. Silver sulfadiazine (1%) served as drug positive control. Microbiological analysis was carried out on 1, 2, 3, 4, and 5 days postwounding (dpw) and histopathological analysis at the end of the experiment (20 dpw). Both ointments demonstrated strong antibacterial activity with complete elimination of MRSA at 48-72 h after infection. The rate of wound contraction was higher (95-100%) in mice groups treated with ASHE and ASDE ointments after 15 dpw. Histological analysis revealed significant increase ( p < 0.05) in epithelialization and collagenation in treated groups. The ASHE and ASDE were found to be relatively noncytotoxic and safe to Vero cell line (383.4  μ g mL -1 ; 390.6  μ g mL -1 ), suggesting the extracts as safe topical antibacterial as well as promising alternatives in managing thermal injuries., Competing Interests: The authors declare that they have no conflict of interests to disclose.

Schistosomiasis is the major source of morbidity in Sub-Saharan Africa and Asia. It is estimated that 207 million people are infected, of which 97% are in Africa. The aim of this study was the determining of prevalence as well as the phylogeny of S. haematobium among school children in Argungu Emirate, Kebbi State Nigeria. A total of 325 urine samples was collected from school children between 7 to 14 years. S. heamatobium eggs was examined under dissecting microscope and DNA was extracted from urine sample and COX1 gene was amplified by nested PCR. The PCR products were purified, sequenced and analysed. This study showed a prevalence of 32.09%, with male pupils having the highest prevalence. S. haematobium infections in children who fetch water in the river have 24 times higher risk of being infected while those who bath in the river have 158 times higher risk of being infected. Our sequences were phylogenetically related to S. haematobium isolate U82266 from Kenya and consistence with the predominant species in Africa. This was the first S. haematobium and S. mansoni co-infection reported in Nigeria. S. haematobium infection is prevalent among school age and significantly associated with water contact.

Background: Antibiotic resistance among Staphylococcus aureus is of great concern worldwide. This resistance is further complicated by the ability of S. aureus to confer cross-resistance to other antibiotics due to the presence of resistance genes, such as erythromycin resistance methylase ( erm ) genes, which render the bacterium resistant to macrolide-lincosamide-streptogramin B (MLSB) antibiotics. Resistance to these antibiotics can lead to therapeutic failure, resulting in significant morbidity and mortality in patients with S. aureus infections., Objectives: This study was performed to examine the distribution of MLSB-resistant strains of methicillin-susceptible S. aureus (MSSA), which were obtained from hospitalized patients and normal healthy individuals (carriers) using phenotypic methods, such as the double-disk diffusion (D-test) and the genotypic method by polymerase chain reaction (PCR)., Methods: A total of 183 nonduplicative MSSA isolates obtained from hospitalized patients (133) and carriers (50) in our previous studies were randomly selected for the D-test. The guidelines of the Clinical and Laboratory Standards Institute (CLSI) were used for the interpretation of the results of this test. The detection of ermA , ermB , ermC and msrA genes by PCR was performed for isolates that had positive D-test results and that were resistant to erythromycin., Results: Of the 183 MSSA isolates, 97.2% and 98.4% were highly susceptible to erythromycin and clindamycin, respectively. MSLB resistance was detected in four isolates (2.2%). Of the 133 MSSA isolated from hospitalized patients, only 3.0% (4/133) and 2.3% (3/133) exhibited resistance to erythromycin and clindamycin, respectively. With regard to the MLSB resistance phenotypes, only 1.6% and 0.6% exhibited inducible MLSB (iMLSB) and MS phenotypes, respectively. The ermC gene was detected in all three iMLSB phenotypes, and the msrA gene was detected in the MS phenotype. Surprisingly, all MSSA isolates (100%) from carriers exhibited extremely high susceptibility to both antibiotics., Conclusions: The prevalence rates of iMLSB MSSA isolates vary according to geographical locations and the local antibiotic policy. The low prevalence rate of iMLSB MSSA isolates could probably be related to the judicious use of antibiotics for treating S. aureus infections in our studied population. Nonetheless, continuous antibiotic surveillance is still necessary to control any emergence of resistance isolates so that targeted therapy and effective control can be implemented accordingly.

The ultimate goal of dental stem cell research is to construct a bioengineered tooth. Tooth formation occurs based on the well-organized reciprocal interaction of epithelial and mesenchymal cells. The dental mesenchymal stem cells are the best explored, but because the human odontogenic epithelium is lost after the completion of enamel formation, studies on these cells are scarce. The successful creation of a bioengineered tooth is achievable only when the odontogenic epithelium is reconstructed to produce a replica of natural enamel. This article discusses the untapped sources of odontogenic epithelial stem cells in humans, such as those present in the active dental lamina in postnatal life, in remnants of dental lamina (the gubernaculum cord), in the epithelial cell rests of Malassez, and in reduced enamel epithelium. The possible uses of these stem cells in regenerative medicine, not just for enamel formation, are discussed.