Zaw Lin

Universiti Malaysia Sabah (UMS) | ums · School of Medicine

The mortality caused by Plasmodium falciparum was reduced by Artemisinin (ART) and ART combination therapy (ACT). However, Artemisinin resistance (ART-R) emerge during 2008 in Cambodia and spread to Greater Mekong Subregion (GMS). ART-R was confirmed not to spread to India, a gateway to whole Africa. The whole genome sequencing approach of P. falci...

Plasmodium knowlesi is now regarded as the fifth malaria parasite causing human malaria as it is widely distributed in South-East Asian countries especially east Malaysia where two Malaysian states namely Sabah and Sarawak are situated. In 2004, Polymerase Chain Reaction (PCR) was applied for diagnosing knowlesi malaria in the Kapit Division of Sar...

Background: Rifampicin (RIF) plays a pivotal role in the treatment of tuberculosis due to its bactericidal effects. Because the action of RIF is on rpoB gene encoding RNA polymerase β subunit, 95% of RIF resistant mutations are present in rpoB gene. The majority of the mutations in rpoB gene are found within an 81bp RIF-resistance determining regi...

Background: Cholera is an important health problem in Sabah, a Malaysian state in northern Borneo; however, Vibrio cholerae in Sabah have never been characterized. Since 2002, serogroup O1 strains having the traits of both classical and El Tor biotype, designated as atypical El Tor biotype, have been increasingly reported as the cause of cholera w...

Escherichia coli sequence type 131 (ST131) carries multiple drug resistance (MDR) genes as well as virulence genes. Drug resistant characteristics give a management problem to health care personnel. Four MDR Escherichia coli ST131 H30-Rx subclones were identified among 80 Uropathogenic E. coli (UPEC) isolates by using 4 allelic-specific Polymerase...

Plasmodium ovale is widely distributed in tropical countries, whereas it has not been reported in the Americas. It is not a problem globally because it is rarely detected by mi-croscopy owing to low parasite density, which is a feature of clinical ovale malaria. P.o. curtisi and P.o. wallikeri are widespread in both Africa and Asia, and were known...

Emergence of multidrug resistant tuberculosis (MDR-TB) and extensively drug resistant tuberculosis (XDR-TB) is one of the reasons why tuberculosis (TB) continues to cause great mortality and morbidity in less-developed countries. The development of rapid diagnostic methods targeting genetic mutations associated with resistance to the anti-tuberculo...

There were 480,000 new cases of multidrug-resistant tuberculosis (MDR-TB) and 100,000 new patients with rifampicin-resistant tuberculosis (RR-TB) in 2015. Mortality was common in Asia with 250,000 deaths in the same year.1 Treatment was successful in 52% of the MDR/RR-TB patients whereas 17% mortality and 9% treatment failure were reported. Extensi...

Background: In the fight against malaria caused by Plasmodium falciparum, the successes achieved by artemisinin were endangered by resistance of the parasites to the drug. Whole genome sequencing approach on artemisinin resistant parasite line discovered k13 gene associated with drug resistance. In vitro and in vivo studies indicated mutations in...

Hearing loss is a common disorder and can be conductive, sensorineural or mixed types. It can be congenital or acquired. In pediatric population more than 50% of deafness is genetic in origin. The patients may present as Deaf, mute or hard of hearing. Literature review was carried out on the pathophysiology including genetics, clinical presentation...

Zika, a mosquito-borne flavivirus was identified in Uganda in 1947 in monkeys. From 1960s to 1980s, the zika viral diseases have been recorded in different parts of the world like Asia, Americas, Africa and the Pacific. Spreading of this viral disease has been observed in more than 60 countries and territories. Brazil has reported the relationship...

Toxigenic strains of Vibrio cholerae serogroup O1 and O139 are causative agents of deadly diarrheal disease named cholera. Vibrio cholerae O1 is traditionally divided into two biotypes, classical and El Tor, which are different in phenotypic as well as genotypic traits. Since 1961, classical strains of Vibrio cholerae O1 serogroup has become obsole...

Escherichia coli (E. coli) is one of the most frequent causes of many bacterial infections especially gastroenteritis in developing countries. It is also used as an indicator for faecal pollution in the surveillance of bacteriological quality of drinking water. This study was conducted to determine the survival of E. coli in water at room temperatu...

Out of bacteria which cause food –borne infections, enterohemorrhagic Escherichia coli (EHEC) is well known to be pathogen causing serious outbreaks. The first outbreak of EHEC infection occurred in 1982 was due to ingestion of hamburger at restaurant. A rare Escherichia coli serotype, 0157:H7 was isolated at that time and the following outbreaks w...

Background: Nasal carriage of Staphylococcus aureus (S.aureus) especially methicillin-resistant S. aureus (MRSA) among health care personnel poses a risk to the patient. Objectives: To determine the prevalence of nasal colonization of S. aureus and its antibiotic susceptibility pattern among pre-clinical and clinical medical and nursing students at...

Introduction: Uropathogenic virulence factors have been identified by comparing the prevalence of these among urinary tract isolates and environmental strains. The uropathogenic-specific protein (USP) gene is present on the pathogenicity island (PAI) of uropathogenic Escherichia coli (UPEC) and, depending on its two diverse gene types and the sequ...

Background: Escherichia coli sequence type 131 (ST131) has emerged among bacteria causing urinary tract infection (UTI) in the previous decade. This ST contains multiple drug resistant (MDR) genes together with genes encoding many virulence factors. As a result, this strain of uropathogenic E. coli (UPEC) gives rise to treatment failure with conseq...

p>Sulphonamides resistant strains are highly prevalent in uropathogenic Escherichia coli (UPEC) isolates. Sul genes encode sulphonamide resistance and are present on transferrable plasmids. Integrons (IGNs) are genetic elements containing integrase gene, attl site and gene cassettes which carry multiple antibiotic resistant genes. Class 1 integrons...

The putative pathogenicity island (PAI) containing the uropathogenic specific protein (usp) gene and three small open reading frames (orfU1, orfU2, and orfU3) encoding 98, 97, and 96 amino acid proteins is widely distributed among uropathogenic Escherichia coli (UPEC) strains. This PAI was designated as PAIusp. Sequencing analysis of PAIusp has rev...

Background: Escherichia coli sequence type 131 (ST131) has emerged among bacteria causing urinary tract infection (UTI) in the previous decade. This ST contains multiple drug resistant (MDR) genes together with genes encoding many virulence factors. As a result, this strain of uropathogenic E. coli (UPEC) gives rise to treatment failure with conseq...

Artemisinin-based combination therapy (ACT) is the first-line therapy in most malaria endemic countries. An impressive 47% reduction in the global mortality rate between 2000 and 2013 has been achieved by ACT and artemisinin (ART) monotherapy. However, artemisinin resistance (AR) by Plasmodium falciparum (P. falciparum) is now prevalent across sout...

Keywords: Uropathogenic Eschericheria coli, class 1 integron, multidrug resistant strains, plasmid-borne Background: Uropathogenic Eschericheria coli (UPEC) isolates were resistant to commonly used antibiotics and multi-drug resistant strains are emerging in hospital settings. Integron (IGN) are genetic elements containing integrase gene, attl site...

The gene encoding a protein which was designated as uropathogenic specific protein was identified on pathogenicity island of uropathogenic Escherichia coli. The usp gene is mainly classified into two types (uspI and uspII) depending on the difference in DNA sequence at the 3’ region. A simple nested polymerase chain reaction assay was applied to di...

The putative pathogenicity island (PAI) containing uropathogenic specific protein (usp) gene and three small open reading frames (orfU1, orfU2 and orfU3) encoding 98, 97 and 96 amino acid protein is widely distributed among UPEC strains. This PAI was designated as PAIusp. Sequencing analysis of PAIusp has revealed that usp gene can be divided into...

Background: The FimH protein is the tip fibrillum of the type 1 fimbria which is adhesive organelle of Escherichia coli (E.coli). Nucleotide sequence variations of fimH gene were common among commensal E. coli, intestinal pathogenic strains and extraintestinal pathogens. Because many researchers pointed out FimH adhesin plays an important role in E...

Artemisinin-based combination therapy (ACT) is the first-line therapy in most malaria endemic countries. However, artemisinin resistance (AR) by Plasmodium falciparum (P. falciparum) is now prevalent across southeast Asia (SEA). Clinical AR is defined as a reduced parasite clearance rate, or a persistence of microscopically detectable parasites on...

Abstract Background: Plasmodium knowlesi is a simian malaria parasite capable of causing malaria in human. Naturally acquired human infections with P. knowlesi have been detected in many South East Asian countries. As P. knowlesi can cause severe malaria with life threatening complications, early detection is of great importance in management of kn...

Abstract Background: Uropathogenic Escherichia coli (UPEC) are the most common bacteria causing urinary tract infection (UTI). The putative pathoge nicity island (PAI) which contains the gene encoding uropathogenic specific protein ( usp ) and three small open reading frames ( orfU1 , orfU2 and orfU3 ) encoding OrfU1, OrfU2 and OrfU3 proteins respe...

Background: The advent of PCR (Polymerase Chain Reaction) assays helped in correctly identifying Plasmodium knowlesi, which was previously misdiagnosed by microscopy as Plasmodium malarie in Sabah, Malaysia. The PCR-based diagnosis of P. knowlesi in Sabah is currently using a set of oligonucleotide primers namely Pmk8 and Pmk9 that target one of th...

Background: The advent of PCR (Polymerase Chain Reaction) assays helped in correctly identifying Plasmodium knowlesi, which was previously misdiagnosed by microscopy as Plasmodium malarie in Sabah, Malaysia. The PCR-based diagnosis of P. knowlesi in Sabah is currently using a set of oligonucleotide primers namely Pmk8 and Pmk9 that target one of th...

Background: Plasmodium knowlesi, an originally zoonotic malaria parasite is now increasingly recognized as a potentially virulent type of human malaria, particularly in South East Asia. The initial diagnosis based on light microscopy would not differentiate P knowlesi from P malaria and the nested PCR (Polymerase Chain Reaction) assay is the only r...

Attempts to isolate Verotoxin-producing Escherichia coli (VTEC) from 53 dead baby cattle were made during a period from January 1989 to July 1991. From 6 cattle of 5 farms, VTECs were isolated. Further examination of cattle from 2 farms with dead baby cattle and from 1 farm with an outbreak of diarrhea among baby cattle, from 8 of 26 cattle with di...

To identify the type of Verotoxins (VT) produced by Verocytotoxin-producing Escherichia coli (VTEC), a sensitive bead-enzyme-linked immunosorbent assay and polymerase chain reaction with common and specific primers to various VTs (VT1, VT2, VT2vha, VT2vhb, and VT2vp1) were developed. Together with colony hybridization tests with oligo- and polynucl...

A simple method for purification of heat-labile enterotoxin produced by enterotoxigenic Escherichia coli and for purification of cholera toxin using immobilized D-galactose column is described. A single run of column chromatography yielded homogeneous toxin as demonstrated by sodium dodecyl sulfate polyacrylamide slab gel electrophoresis.

A bead-enzyme-linked immunosorbent assay to specifically detect a Verotoxin 2 variant, VT2vp1, was developed. The sensitivity of the bead-ELISA was 200 pg/ml of the purified VT2vp1 and it did not react with 20 ng/ml of the purified VT2. The specificity of the bead-ELISA was examined with 107 strains of Verocytotoxin-producing Escherichia coli that...

In an effort to identify the regulatory gene controlling the expression of the tdh gene, encoding the thermostable direct hemolysin of Vibrio parahaemolyticus, we examined total DNA of AQ3815 (a Kanagawa phenomenon-positive strain) for sequences homologous to that of the toxR gene of Vibrio cholerae. The extracted DNA gave a weak hybridization sign...

We cloned and sequenced two new Verotoxin 2 (VT2) variant genes: one from an Escherichia coli strain from a case of bovine diarrhea and the other from an E. coli strain from a patient with diarrhea. The nucleotide and amino acid sequences of these two genes were highly homologous with, but distinct from those of the VT2, VT2vha, VT2vhb, SLT-IIv (VT...

We constructed common primers for the polymerase chain reaction to detect the genes for various Verotoxins reported, that is, VT1 (or SLT-I), VT2 (or SLT-II), VT2vha, VT2vhb, SLT-IIv (or VT2vp1, VTe) and SLT-IIva (or VT2vp2). A total of 80 Verocytotoxin-producing Escherichia coli strains isolated from humans, domestic animals and meats gave a posit...

During a three-year period (1987 & 1990), a comprehensive attempt was made to isolate verocytotoxin-producing Escherichia coli (VTEC) from 96 bovine, 89 porcine, 67 canine and 18 feline cases suffering from gastroenteritis. VTEC were isolated from 11 cows and 1 cat. Bead-ELISA and oligonucteotide probes were used to type the verotoxins (VT) and it...