1.The Role of Reactive Oxygen Species in Pressure-Dependent Myogenic Tone
Satirah Zainal Abidin ; Paul Coats ; Roger M. Wadsworth
Malaysian Journal of Health Sciences 2012;10(1):1-11
Myogenic tone is the response of the vascular smooth muscle to an increase in intraluminal pressure with vasoconstriction and with vasodilation when the pressure is decreased. Such myogenic tone contributes a level of physiological basal tone in response to neurohumoral stimuli. In spite of myogenic tone discovery by Sir William Bayliss 100 years ago, questions still remain regarding the underlying signaling mechanism of the myogenic response. Studies have shown that increased intraluminal pressure or wall tension leads to membrane depolarization, voltage-operated calcium channel (VOCC), stretch-activated cation (SAC) channels, extracelullar matrix (ECM) and actin cytoskeleton. Recently, evidence has shown a potential role for reactive oxygen species (ROS) as a key signalling mediator in the genesis of myogenic tone. The identification of the primary mechanosensors in the initiation of pressure-dependent myogenic tone is essential as these components could be potential therapeutical targets in the future.
2.Acute Paraplegia in a Toddler: A Diagnostic Journey Compounding the Challenge in Management: A Case Report
Goh JH ; Fazir M ; Zainal-Abidin NA ; Amir D ; Singh M
Malaysian Orthopaedic Journal 2016;10(2):56-60
Spinal tuberculosis is not common in the paediatric age
group. Initial clinical features are often vague and non
specific until the disease progresses to later stages. We
highlight the diagnostic difficulties and management
challenges of a complicated extradural tuberculoma with
neurological deficits in a very young girl.
Tuberculosis, Spinal
3.Cyclin D1 expression in acral melanoma: a case control study in Sarawak
Zainal Abidin Ibrahim ; M Zulkarnaen A Narihan ; Dk Norlida A Ojep ; Ashley Edward Roy Soosay ; Kak Long Pan
The Malaysian Journal of Pathology 2012;34(2):89-95
Acral melanoma has been reported to have distinctive clinical presentation and ethnic distribution
compared to other histological types of malignant melanoma. Acral melanoma also exhibits distinctive
focused gene amplifi cations, including cyclin D1 overexpression. We reviewed archived histological
material of malignant melanoma in the Sarawak General Hospital from year 2004 to 2010. 43
tumours, comprising 28 acral melanoma and 15 non-acral melanoma, had suffi cient material to be
included in the study. The majority (36%) of acral melanoma tumours occurred in the heel. The
tumours were analyzed for cyclin D1 expression by immunohistochemistry. 68% of acral melanoma
were cyclin D1 positive compared to a positivity of 33% in non-acral tumours. This difference
was statistically signifi cant (p <0.05). This fi nding may improve the histological diagnosis of acral
melanoma and detection of positive resection margins.
4.Isolation and molecular characterization of Brucella melitensis from seropositive goats in Peninsula Malaysia
Bamaiyi, P.H. ; Hassan, L. ; Khairani-Bejo, S. ; Zainal Abidin, M. ; Ramlan, M. ; Krishnan, N. ; Adzhar, A. ; Abdullah, N. ; Hamidah, N.H.M. ; Norsuhanna, M.M. ; Hashim, S.N.
Tropical Biomedicine 2012;29(4):513-518
A study was carried out to isolate Brucella melitensis using established
bacteriological and PCR techniques in Brucella seropositive goats in farms in Selangor, Negeri
Sembilan, Melaka and Pulau Pinang. Brucella melitensis was isolated from 7 of 134 reactors
with the highest isolation from the vaginal swabs (57.14%) followed by the spleen (28.57%),
uterine fluid (14.29%). No Brucella was isolated from the lymph nodes. PCR confirmed all the
seven isolates as B. melitensis and isolates were phylogenetically related to other isolates
from India, Iran, and Israel but most closely related to isolates from Singapore.
5.The Effects of Three and Six Sessions of Low Energy Extracorporeal Shockwave Therapy on Graft Incorporation and Knee Functions Post Anterior Cruciate Ligament Reconstruction
Rahim M ; Ooi FK ; Shihabudin MT ; Chen CK ; Musa AT
Malaysian Orthopaedic Journal 2022;16(No.1):28-39
Introduction: One session of high energy extracorporeal
shockwave therapy (ESWT) was found to improve the
healing of anterior cruciate ligament (ACL) after
reconstruction in animal and human studies. This study
investigated the effects of three and six sessions of low
energy ESWT on graft incorporation and knee functions post
ACL reconstruction in humans.
Materials and methods: Thirty participants with ACL
injuries were recruited and assigned equally into three
groups with 10 participants per group (n=10). Participants in
the control group received physiotherapy alone without low
energy ESWT. Participants in the 3ESWT group underwent
three sessions of low energy ESWT (one session per week)
combined with physiotherapy, and participants in the
6ESWT group received six sessions of low energy ESWT
(one session per week) combined with physiotherapy.
However, five participants were lost to follow-up.
Evaluations of graft incorporation of the tibial tunnel using
magnetic resonance (MRI) and Lysholm score were carried
out before ACL reconstruction and after six months post
ACL reconstruction.
Results: The number of grafts with partial incorporation in
the tibia tunnel in 6ESWT was significantly higher compared
with the number of grafts with non-incorporation at six
months post-operatively, X2 (1, N=9) =5.44, p =0.02.
However, there was no significant difference between
frequencies of graft incorporation in tibia tunnel in the
control and 3ESWT groups, X2 (1, N=7) =3.57, p =0.06 and
X2 (1, N=9) =2.78, p =0.10, respectively at 6 months postoperatively. Lysholm scores were significantly higher at 6
months post ACL reconstruction compared to the baseline
value for each group (p<0.002, respectively). However, there
was no significant difference in the Lysholm score between
each group (F = 2.798, p = 0.083).
Conclusions: Six sessions of low energy ESWT improved
graft incorporation in the tibial tunnel. Both three and six
sessions of low energy of ESWT does not affect the knee
function score at six months post ACL reconstruction.
6.Single and co-breeding of different mosquito species in fogging-free and dengue risk areas in West Malaysia
Wan-Norafikah, O. ; Chen, C.D. ; Mohd-Amir, M.H ; Azahari, A.H. ; Zainal-Abidin, A.H ; Nazni, W.A. ; Mariam, M. ; Mohd-Shahizan, J. ; Sofian-Azirun, M.
Tropical Biomedicine 2018;35(3):826-838
Ovitrap surveillance was carried out in fifteen localities encompassing foggingfree
and dengue risk areas in West Malaysia to determine on the dispersal and prevalence of
single and co-breeding of mosquito larvae particularly Aedes. Ovitraps were sited randomly
indoors and outdoors within human settlements in all study areas. All the localities exhibited
positive ovitraps with single breeding of Ae. albopictus that ranged between 64.29% and
100.00%. These findings indicated Ae. albopictus as the predominant container-breeding
species in all study areas. The co-breeding of Ae. aegypti with Ae. albopictus larvae (34
ovitraps), Ae. albopictus with Culex quinquefasciatus larvae (32 ovitraps) as well as Cx.
quinquefasciatus with Armigeres subalbatus larvae (1 ovitrap) were also detected in certain
study localities. Interestingly, co-breeding of Ae. albopictus with Ar. subalbatus larvae as
well as Ae. albopictus with Uranotaenia sp. larvae in Malaysia is reported for the first time in
the present study. Better understanding of the co-breeding scenario involving different species
of mosquito larvae is needed to ensure the efficacy of vector control actions to be conducted.