Demonstrasi Kehadiran Protein Permukaan Sel Yang Antigenik Dan Spesifik Untuk Shigella Spp. Dan Pembangunan Ke Arah Ujian Diagnostik Segera Bagi Penyakit Shigelosis

Shigella spp. is the major etiologic agent of dysentery or bloody diarrhoea in humans. It has been identified as an important cause for morbidity and mortality among children especially in developing countries. Early diagnosis of shigellosis is the major strategy for limiting this highly contagious disease. Since routine culturing and bacterial determination from patients' faeces are laborious, timeconsuming, relatively expensive and of low sensitivity, the development of a more rapid and simplified diagnostic test for shigellosis is highly desirable. The test must be sensitive, specific, easy to perform, cost-effective and be able to detect the presence of Shigella spp. directly from patients' specimen especially faeces. As such, the objective of this study was to determine the presence of a specific and antigeniC protein for Shigella spp. and to use it for the development of a rapid diagnostic test for shigellosis

Molecular Characterization And Production Of A Specific Recombinant Protein Of Shigella Flexneri : Towards Development Of A Rapid Immunochromatography Diagnostic Test For Dysentery [QR82.E6 K58 2006 f rb].

Disenteri basilus atau juga dikenali sebagai shigelosis disebabkan terutamanya oleh bakteria Shigella. Shigelosis merupakan suatu penyakit yang serius di mana hampir 165 juta penduduk dijangkiti setiap tahun. Bacillary dysentery is caused mainly by infection with Shigella spp. which is also known as shigellosis. It remains a common and serious health problem throughout the world and has been estimated to infect about 165 million people worldwide annually

Molecular Characterization And Production Of A Specific Recombinant Protein Of Shigella Flexneri: Towards Development Of A Rapid Immunochromatography Diagnostic Test For Dysentery

Disenteri basilus atau juga dikenali sebagai shigelosis disebabkan terutamanya oleh bakteria Shigella. Bacillary dysentery is caused mainly by infection with Shigella spp. which is also known as shigellosis

Kertas kerja 3rd. congress of european microbiologists " microbes and maninterdepence and future challenges" 27 Jun - 03 Julai 2009 di Goteborg, Sweden

Background: The Work:t Health Organization are emphasizing that the development of vaccines for Shigella is a priority. Despite many studies have been carried out on this pathogenic bacterium, but to date no vaccines are commercially available for the pubic health purposes. Apyrase is an ATP"iphosphohydrolase enzyme coded by the virulence plasmid-encoded phoN2 (spy) gene which have been suggested to be involved in proper unipolar lcsA localization and for efficient intercellular spread in Shigella. Objective: The aim of this study was to develop an apy mutant of Shigella flexneri by insertional inactivation using a kanamycin resistant gene cassette. Methods: The wild apy gene of Shigella ffexneri 2a (738 bp) was PCR amplified and the amplified gene was cloned into pTZ57R. A unique Hpa1 was identified in apy gene and a kanamycin resistant gene cassette (aphA) was inserted at the Hpa1 site of apy gene. The mutated construct (apy:aphA) was then subcloned into pWM91conjugative suicidal vector and the constructed plasmid was verifted by DNA sequencing. The mutated construct was then introduced into wild Shigella flexneri 2a by conjugation with E. coli. After undergoing homologous recombination, the wild apy gene was deleted from the construct. Results: The apy gene was successfully cloned and mutated using a kanamycin resistant gene cassette. The construct was successfully transfonned into Shigella flexneri 2a and the wild apy gene has been successfully deleted from the constructed strain. Discussion and conclusion: The mutation of apy gene is a novel approach towards the development of a potential live attenuated vaccine for Shigella; as apy gene is a potential virulence gene candidate. Further studies are in progress to evaluate the efficiency of this vaccine candidate

Serum neopterin is elevated in patients infected with Shigella

<p>Abstract</p> <p>Background</p> <p>Neopterin is produced by human macrophages/monocytes when stimulated with interferon-gamma. Production of neopterin is found in serum, cerebrospinal fluid (CSF) and urine of patients with infections by viruses, intracellular bacteria and parasites, autoimmune diseases, malignant tumors and patients in allograft rejection episodes.</p> <p>Methods</p> <p>In this study, the level of neopterin was determined in serum samples obtained from patients infected with <it>Shigella </it>(all four species) and healthy individuals. The study population comprised of 14 patients infected with <it>Shigella </it>and 14 normal controls. Serum neopterin was measured using an enzyme-linked immunosorbent assay (ELISA).</p> <p>Results</p> <p>The mean of serum neopterin concentration was 36.32 ± 9.71 nmol/L among patients infected with <it>Shigella </it>and 2.88 ± 0.77 nmol/L in the control group. The mean serum neopterin levels were significantly higher in the test group as compared to the normal group (p = 0.002).</p> <p>Conclusion</p> <p>This study revealed that neopterin was elevated in patients infected with <it>Shigella</it>.</p

Outer membrane proteins analysis of Shigella sonnei and evaluation of their antigenicity in Shigella infected individuals

Bacillary dysentery caused by infection with Shigella spp. remains as serious and common health problem throughout the world. It is a highly multi drug resistant organism and rarely identified from the patient at the early stage of infection. S. sonnei is the most frequently isolated species causing shigellosis in industrialized countries. The antigenicity of outer membrane protein of this pathogen expressed during human infection has not been identified to date. We have studied the antigenic outer membrane proteins expressed by S. sonnei, with the aim of identifying presence of specific IgA and IgG in human serum against the candidate protein biomarkers. Three antigenic OMPs sized 33.3, 43.8 and 100.3 kDa were uniquely recognized by IgA and IgG from patients with S. sonnei infection, and did not cross-react with sera from patients with other types of infection. The antigenic proteome data generated in this study are a first for OMPs of S. sonnei, and they provide important insights of human immune responses. Furthermore, numerous prime candidate proteins were identified which will aid the development of new diagnostic tools for the detection of S. sonnei

A Pentaplex PCR Assay for the Detection and Differentiation of Shigella Species

The magnitude of shigellosis in developing countries is largely unknown because an affordable detection method is not available. Current laboratory diagnosis of Shigella spp. is laborious and time consuming and has low sensitivity. Hence, in the present study, a molecular-based diagnostic assay which amplifies simultaneously four specific genes to identify invC for Shigella genus, rfc for S. flexneri, wbgZ for S. sonnei, andrfpB for S. dysenteriae, aswell as one internal control (ompA) gene, was developed in a single reaction to detect and differentiate Shigella spp. Validation with 120 Shigella strains and 37 non-Shigella strains yielded 100% specificity. The sensitivity of the PCR was 100 pg of genomic DNA, 5.4 × 104 CFU/ml, or approximately 120 CFU per reaction mixture of bacteria. The sensitivity of the pentaplex PCR assay was further improved following preincubation of the stool samples in Gram-negative broth. A preliminary study with 30 diarrhoeal specimens resulted in no cross-reaction with other non-Shigella strains tested. We conclude that the developed pentaplex PCR assay is robust and can provide information about the four target genes that are essential for the identification of the Shigella genus and the three Shigella species responsible for the majority of shigellosis cases

Antibacterial properties of tualang honey and its effect in burn wound management: a comparative study

<p>Abstract</p> <p>Background</p> <p>The use of honey as a natural product of <it>Apis </it>spp. for burn treatment has been widely applied for centuries. Tualang honey has been reported to have antibacterial properties against various microorganisms, including those from burn-related diagnoses, and is cheaper and easier to be absorbed by Aquacel dressing. The aim of this study is to evaluate the potential antibacterial properties of tualang honey dressing and to determine its effectiveness as a partial thickness burn wound dressing.</p> <p>Methods</p> <p>In order to quantitate the bioburden of the swabs, pour plates were performed to obtain the colony count (CFU/ml). Swabs obtained from burn wounds were streaked on blood agar and MacConkey agar for bacterial isolation and identification. Later, antibacterial activity of Aquacel-tualang honey, Aquacel-Manuka honey, Aquacel-Ag and Aquacel- plain dressings against bacteria isolated from patients were tested (<it>in-vitro</it>) to see the effectiveness of those dressings by zone of inhibition assays.</p> <p>Results</p> <p>Seven organisms were isolated. Four types of Gram-negative bacteria, namely <it>Enterobacter cloacae</it>, <it>Klebsiella pneumoniae</it>, <it>Pseudomonas </it>spp. and <it>Acinetobacter </it>spp., and three Gram-positive bacteria, namely <it>Staphylococcus aureus</it>, coagulase-negative <it>Staphylococcus aureus </it>(CONS) and <it>Streptococcus </it>spp., were isolated. Total bacterial count decreased on day 6 and onwards. In the <it>in-vitro </it>antibacterial study, Aquacel-Ag and Aquacel-Manuka honey dressings gave better zone of inhibition for Gram positive bacteria compared to Aquacel-Tualang honey dressing. However, comparable results were obtained against Gram negative bacteria tested with Aquacel-Manuka honey and Aquacel-Tualang honey dressing.</p> <p>Conclusions</p> <p>Tualang honey has a bactericidal as well as bacteriostatic effect. It is useful as a dressing, as it is easier to apply and is less sticky compared to Manuka honey. However, for Gram positive bacteria, tualang honey is not as effective as usual care products such as silver-based dressing or medical grade honey dressing.</p