1.Isolation and Identification of an Emerging Pathogen, Kocuria marina, from Rattus rattus diardii
Loong, S.K. ; Johari, J. ; Che Mat Seri, N.A.A. ; AbuBakar, S.
Tropical Biomedicine 2016;33(3):589-593
Members of the genus Kocuria are commonly found in the environment and they
are also commensals of the mammalian skin and oropharynx mucosa. Human infections,
although rare, are increasingly being reported recently suggesting that this genus has mostly
been overlooked or misidentified. Its transmission route however, is still not known. We
report here the isolation and identification of a Kocuria marina isolate from the lung of a
wild urban rat (Rattus rattus diardii) caught at a wet market. The isolate was susceptible to
most of the commonly used antibiotics. The finding suggests a possibility that rats could be
a vector for K. marina.
2.A Report of Vancomycin-susceptible, Teicoplanin-resistant Enterococcus faecalis ST6 in Malaysia
Loong, S.K. ; Che Mat Seri, N.A.A. ; Mahfodz, N.H. ; Akbar, S.Z. ; AbuBakar, S.
Tropical Biomedicine 2016;33(3):577-582
The ability to acquire antibiotic resistance and virulence has propelled Enterococcus
faecalis to become a major nosocomial pathogen. In Malaysia, data on the antibiotic resistance
determinants and virulence of Enterococcus circulating strains are still scarce. This study
aimed to assess the genotype of an E. faecalis isolate initially identified as Streptococcus
uberis, examine the antibiotic resistance genotypes, analyze the genetic variations within
Tn1546 and investigate the presence of virulence genes. The E. faecalis isolate was genetically
characterized using multilocus sequence typing (MLST). Minimum inhibitory concentrations
to vancomycin and teicoplanin were determined. Antibiotic resistance and other virulence
genes were amplified using nucleic acid polymerase chain reaction. Mapping of the Tn1546
transposon was performed and compared to the prototype sequences. The E. faecalis isolate
was found to have a MLST profile corresponding to sequence type 6. The isolate was resistant
to teicoplanin but susceptible to vancomycin. Its genome consisted the vanA and vanC1
genes. Novel genetic variations in the vanS, vanS-vanH intergenic region and vanY genes
were present and six virulence genes were detected. The detection of the vanC1 gene,
thought to be non-transferable, suggests the potential emergence of inter-species enterococcal
vanC1 gene transfer. The peculiar antibiotics resistance phenotype of this E. faecalis isolate
could be associated to the novel genetic variations found. This study highlights the presence
of E. faecalis belonging to the high-risk clonal complex with multiple virulence factors in
Malaysia.
3.Emergence of Enterococcus gallinarum carrying vanA gene cluster displaying atypical phenotypes
Loong, S.K. ; Che Mat Seri, N.A.A. ; Mahfodz, N.H. ; Teoh, B.T. ; AbuBakar, S.
Tropical Biomedicine 2016;33(4):837-841
Motile enterococci such as Enterococcus gallinarum has the ability to acquire
and transfer antibiotic resistance genes to other enterococci. Even though infections caused
by E. gallinarum are rare, the discovery of this bacteria in food sources and in clinical
environments is disturbing. Here, we report the isolation and identification of E. gallinarum
from the wound of a hospital in-patient. The isolate was identified using 16S rDNA sequencing.
Isolate 146 harboured the vanA and vanC1 gene clusters, was vancomycin-susceptible, and
displayed resistance to ampicillin, penicillin, erythromycin and teicoplanin. This isolate also
showed intermediate resistance to linezolid and sequencing of the 23S rRNA peptidyl
transferase region did not unveil any known mutations associated to the conferment of
linezolid resistance. The presence of vanA did not confer resistance to vancomycin. Structural
analyses into the Tn1546 transposon carrying the vanA gene revealed distinct genetic variations
in the vanS, vanY and vanS-vanH intergenic region that could be associated to the atypical
antibiotic resistance phenotypes of isolate 146. Finding from this study are suggestive of the
occurrence of interspecies horizontal gene transfer and that similarities in genotypic
characteristic may not necessarily correlate with actual antibiotic resistance pattern of E.
gallinarum.
4.The Impact of Dry Needling on Patients with Neck Pain in a Tertiary Hospital
Ho SE ; Loong S ; Fatin Nur Laily R ; Wan Nur Aizzati M ; Muhamad Firdaus IZ ; Christopher Ho CK ; Katijah Bee MA ; Henry LJ ; Ismail MS
Journal of Surgical Academia 2015;5(1):44-50
Neck pain presents as a symptom of dull pain or discomfort mainly along the trapezius muscle. Dry needling is an
invasive procedure which uses acupuncture needle directed at myofascial trigger points. The aim of the study was to
evaluate the effectiveness of dry needling in managing patients with neck pain. A pre-test-post-test interventional
study design was used. Patient education package was provided to 32 respondents who fulfilled the inclusion criteria.
A 13-item Pain Catastrophizing Scale (PCS) questionnaire was used to assess Rumination, Magnification and
Helplessness. Subjective pain intensity was measured by Visual Analogue Scale (VAS). These questionnaires were
given before and after the dry needling intervention. The findings reported that respondents scored high in pre-test
total PCS score (27.41±13.652). Post-test result revealed a significant improvement in total PCS score
(23.06±13.938) (p = 0.000). Post-test VAS score (4.78±1.237) was also significantly better than pre-test
(6.47±1.414) (p = 0.000). There was no significant difference in pre-test PCS in terms of marital status (p > 0.05)
whereas there was significant difference between marital status and rumination in post-test (Z = -2.303, p = 0.021).
There was significant difference between pre-test magnification in terms of respondents’ occupation (p = 0.008) and
race (p = 0.035) but no significant difference in post-test. Respondents’ age group showed no significant differences
between pre-test and post-test PCS and VAS (p > 0.05). In conclusion, patients who received dry needling showed
improvement in pain intensity and catastrophizing towards neck pain.
Neck Pain
6.Bacterial profiling of head lice isolated from the Orang Asli: A first report in Malaysia
Abd Majid, M.A. ; Khoo, J.-J. ; Lim, F.-S. ; Khor, C.-S. ; Loong, S.-K. ; Low, V.-L. ; Lee, H.-Y. ; AbuBakar, S.
Tropical Biomedicine 2020;37(No.4):884-895
This study was carried out to determine from bacterial profiling to the bacterial
profiles of head lice among the Orang Asli communities. The head lice were collected from
Orang Asli community volunteers. The surface sterilized head lice pools were subjected to
genomic DNA extraction while next generation sequencing of the 16S rRNA gene was
performed using the Illumina MiSeq platform. Six female and three male head lice identified
as Pediculus humanus capitis were collected. A total of 111 368 number of NGS sequencing
reads were recorded while another 223 bacterial taxa sequences were obtained. Symbiotic
bacteria showed the highest number of reads, with Arsenophonus and Rhodococcus sequences
being the most abundant genera in the female and male samples, respectively. The female
head lice contained a more distinct microbial diversity. Amongst the pathogenic bacterial
species sequences noted were the methicillin-resistant Staphylococcus aureus, Streptobacillus
moniliformis, Haemophilus influenzae, Bordetella pertussis and Acinetobacter baumannii.
The 16S rRNA genome sequencing revealed a number of rare and pathogenic bacterial
species within the head lice of the Orang Asli. The socio-economic practices of the community
which involved forest foraging and hunting, and their poor living conditions potentially
facilitated the transmission of zoonotic bacterial pathogens, including those found within the
head lice. Hence, there is the possibility that the head lice could serve as vectors for the
transmission of pathogenic bacteria. This study highlighted the diverse microbial community
found within the head lice’s gut of the Orang Asli, with the detection of multiple rare and
pathogenic bacteria capable of causing severe infections.
7.Sunlight exposure might account for the relatively low COVID-19 morbidity and mortality in tropical countries
Muhammad, M. ; Loong, S.K. ; Khor, C.S. ; Mohd-Azami, S.N.I. ; Kafle, A. ; Useh, U. ; Bello, B. ; AbuBakar, S.
Tropical Biomedicine 2024;41(No.1):78-83
The present study aimed at exploring whether sunlight exposure might account for the relative
difference in COVID-19-related morbidity and mortality between tropical and non-tropical countries.
A retrospective observational study was designed and data from the World Health Organization
weekly COVID-19 epidemiological update was compiled. We examined the total number of confirmed
COVID-19 cases per 100 000 population, as well as the total number of COVID-19-related mortalities
per 100 000 population. Solar variables data were obtained from the Global Solar Atlas website
(https://globalsolaratlas.info/). These data were analyzed to determine the association of sunlight
exposure to COVID-19-related morbidity and mortality in tropical and non-tropical countries. Results
revealed a statistically significant decrease in the number of confirmed COVID-19 cases per 100 000
population (P<0.001), as well as the number of COVID-19-related mortalities per 100 000 population
(P<0.001) between tropical and non-tropical countries. Analyses of sunlight exposure data found that
specific photovoltaic power output, global horizontal irradiation, diffuse horizontal irradiation and
global tilted irradiation at optimum angle were significantly inversely correlated to COVID-19-related
morbidity and mortality. This suggests that stronger sunlight exposure potentially leads to lower
COVID-19-related morbidity and mortality. Findings from this study suggest that the relatively low
COVID-19-related morbidity and mortality in tropical countries were possibly due to better sunlight
exposure that translates into adequate vitamin D status.
8.Culturable pathogenic bacteria in ticks parasitizing farm animals and rodents in Malaysia
Loong, S.K. ; Lim, F.S. ; Khoo, J.J. ; Lee, H.Y. ; Suntharalingam, C. ; Ishak, S.N. ; Mohd-Taib, F.S. ; AbuBakar, S.
Tropical Biomedicine 2020;37(No.3):803-811
Ticks are vectors of bacteria, protozoa and viruses capable of causing serious and life threatening diseases in humans and animals. Disease transmission occurs through the transfer of pathogen from tick bites to susceptible humans or animals. Most commonly known tick-borne pathogens are obligate intracellular microorganisms but little is known on the prevalence of culturable pathogenic bacteria from ticks capable of growth on artificial nutrient media. One hundred and forty seven ticks originating from dairy cattle, goats and rodents were collected from nine selected sites in Peninsular Malaysia. The culture of surfacesterilized tick homogenates revealed the isolation of various pathogenic bacteria including, Staphylococcus sp., Corynebacterium sp., Rothia sp., Enterococcus faecalis, Klebsiella pneumoniae, Escherichia coli and Bacillus sp. and its derived genera. These pathogens are among those that affect humans and animals. Findings from this study suggest that in addition to the regular intracellular pathogens, ticks could also harbor extracellular pathogenic bacteria. Further studies, hence, would be needed to determine if these extracellular pathogens could contribute to human or animal infection.
9.Development of a TaqMan minor groove binding probe-based quantitative reverse transcription polymerase chain reaction for the detection and quantification of Zika virus
Chin, K.L. ; Teoh, B.T. ; Sam, S.S. ; Loong, S.K. ; Tan, K.K. ; Azizan, N.S. ; Lim, Y.K. ; Khor, C.S. ; Nor&rsquo ; e, S.S. ; Abd-Jamil, J. ; AbuBakar, S.
Tropical Biomedicine 2022;39(No.4):518-523