1.Dual time point imaging of FDG PET/CT in a tuberculous spondylodiscitis
HR Abdul Razak ; N Abdul Rahim ; AJ Nordin
Biomedical Imaging and Intervention Journal 2010;6(2):1-3
Dual Time Point Imaging (DTPI) technique is a specialised protocol adopted in 18F-Fluorodeoxyglucose (FDG)
Positron Emission Tomography (PET) imaging. This technique is claimed to be useful in differentiating malignant and
infective lesions. The authors adopted this technique in a patient diagnosed with tuberculous spondylodiscitis and psoas abscess which demonstrated higher Maximum Standardized Uptake Value (SUVmax) during initial scans as compared with those obtained on delayed scans. The SUVmax changes between the two time points are believed to be a valuable finding for chronic granulomatous infective lesions such as tuberculosis.
2.Interleukin-27 exhibited anti-inflammatory activity during Plasmodium berghei infection in mice.
Fazalul Rahiman, S S ; Basir, R ; Talib, H ; Tie, T H ; Chuah, Y K ; Jabbarzare, M ; Chong, W C ; Mohd Yusoff, M A ; Nordin, N ; Yam, M F ; Abdullah, W O ; Abdul Majid, R
Tropical Biomedicine 2013;30(4):663-80
Interleukin-27 (IL-27) has a pleiotropic role either as a pro-inflammatory or anti-inflammatory cytokine in inflammatory related diseases. The role and involvement of IL-27 during malaria was investigated and the effects of modulating its release on the production of major inflammatory cytokines and the histopathological consequences in major affected organs during the infection were evaluated. Results showed that IL-27 concentration was significantly elevated throughout the infection but no positive correlation with the parasitaemia development observed. Augmentation of IL-27 significantly elevated the release of anti-inflammatory cytokine, IL-10 whereas antagonising and neutralising IL-27 produced the opposite. A significant elevation of pro-inflammatory cytokines (IFN-γ and IL-6) was also observed, both during augmentation and inhibition of IL-27. Thus, it is suggested that IL-27 exerts an anti-inflammatory activity in the Th1 type response by signalling the production of IL-10 during malaria. Histopathological examination showed sequestration of PRBC in the microvasculature of major organs in malarial mice. Other significant histopathological changes include hyperplasia and hypertrophy of the Kupffer cells in the liver, hyaline membrane formation in lung tissue, enlargement of the white and red pulp followed by the disappearance of germinal centre of the spleen, and tubular vacuolation of the kidney tissues. In conclusion, it is suggested that IL-27 may possibly acts as an anti-inflammatory cytokine during the infection. Modulation of its release produced a positive impact on inflammatory cytokine production during the infection, suggesting its potential in malaria immunotherapy, in which the host may benefit from its inhibition.
3.Group B streptococcus infection in a sudden unexpected death of infancy – the importance of microbiological investigation at post-mortem
Khalid, N ; Zainun, K.A ; Hisham, S ; Mazan, N.I ; Amin Nordin, S
Tropical Biomedicine 2018;35(3):604-609
Group B streptococcus (GBS) is a common cause of infection in newborns and in
early infants. However, GBS infection in an infant older than three months is infrequently
reported in the literature. We reported a case of an apparently well six-month-old infant who
died of sudden death due to GBS pneumonia, diagnosed at autopsy. The six-month-old,
apparently well male infant was brought in dead to the Emergency Department. He underwent
medicolegal autopsy four hours after death, as part of an overall sudden unexpected death in
infancy investigation (SUDI). Apart from whitish froth oozing out of both nostrils, he appeared
to be well-nourished infant without any deformity, syndromic features or obvious suspicious
marks of injury externally. Internal examination showed generalized hyperinflated with patchy
consolidation of upper and middle lobes of bilateral lung. Multiple matted mesenteric
lymphadenopathy were also detected. Blood and lung tissue specimens collected under
aseptic technique yielded growth of GBS. Post-mortem histology from consolidated lungs
confirmed pneumonic features while mesenteric lymph nodes showed reactive changes inkeeping with underlying infective process. Death was attributed to GBS pneumonia. This
case highlights the importance of a detailed autopsy in sudden unexpected death in infancy
(SUDI) and the crucial role of post-mortem microbiological study in such cases. Relevant
autopsy protocols that need to be employed during microbiological sampling are briefly
discussed.
4.COMPARISON OF PATHOGENESIS OF P. BERGHEIINFECTION IN MOUSE AND RAT MODELS
Chin VK ; Chong WC ; Nordin N ; Lee TY ; Zakaria ZA ; Hassan H ; Basir R
Journal of University of Malaya Medical Centre 2019;22(2):4-12
Background: The cytokine cascade in the immunopathogenesis of malaria infection had been widely studied. However, their specific association with survival and severe infection remained obscure.Methods: Thestudy investigated the cytokine profiles and histopathological features of malaria in the severe infection and survival models by using male ICR mice and male Sprague Dawley rats respectively.Results: The severe model, the infected ICR mice, exhibited a high parasitemia with 100% mortality after peak parasitemia at day 5 post-infection. The survival model, the infected Sprague Dawley rats, showed mild parasitemia with full recovery by day 14 of infection. Both severe and survival models showed similar histopathological severity during peak parasitemia. The severe model produced highly elevated levels of pro-inflammatory cytokines, TNF-α and IL-1α, and low levels of the anti-inflammatory cytokine, IL-4; while the survival model showed low levels of TNF-α and IL-1α with high levels of IL-4.Conclusion: There were differences in the pathogenesis of the severe and survival models of malaria infection. These could be a basis for immunotherapy of malaria in the future
5.Inhibition of Activin A suppressed tumor necrosis factor-α secretion and improved histopathological conditions in malarial mice
Chin, V.K. ; Tie, T.H. ; Abd Majid, R. ; Hassan, H. ; Nordin, N. ; Abas, R. ; Basir, R.
Tropical Biomedicine 2021;38(No.1):187-204
Malaria infection still remains as one of the most prominent parasitic diseases afflicting
mankind in tropical and subtropical regions. The severity of malaria infection has often
been associated to exuberant host immune inflammatory responses that could possibly
lead to severe immunopathological conditions and subsequent death of host tissues. Activin
A is a protein belonging to the transforming growth factor-beta (TGF-β) family that regulates
multiple physiological processes and pathological-associated diseases. The biological
roles of activin A have been associated with manipulation of inflammation-related processes
and modulation of host immune responses. This implies that activin A protein could play a
role in malaria pathogenesis since malaria infection has been closely linked to severe
immune responses leading to death, However, the actual in vivo role of activin A in malaria
infection remains elusive. Hence, this study was undertaken to investigate the involvement
of activin A in malaria infection as well as to assess the modulating effects of activin A on
the cytokine releases (TNF-α, IFN-γ and IL-10) and histopathological changes in major affected
organs (kidney, liver, lung, brain and spleen) in malarial mice infected with Plasmodium
berghei ANKA. Our results showed that the concentrations of plasma activin A were significantly
increased in malarial mice throughout the study periods. Also. the systemic activin A level
was positively correlated with malaria parasitemia. This indicates that activin A could play
a role in malaria pathogenesis and malaria parasitemia development. Plasma TNF-α,
IFN-γ and IL-10 cytokine levels were significantly increased in malarial mice at day-5 post
infection, suggesting that these cytokines attributed to severe malaria pathogenesis.
Histopathological features such as sequestration of parasitized red blood cells (pRBCs)
and hemozoin formation were amongst the most common pathological conditions observed
in tissues of major affected organs (kidney, liver, lung, brain and spleen) in malarial mice.
Neutralization of activin A production via recombinant mouse activin RIIA Fc chimera (rmActivin
RIIA Fc chimera) had significantly reduced the parasitemia levels in malarial mice. The
release of TNF-α cytokine was significantly reduced as well as the sequestration of
parasitized pRBCs and hemozoin formation in major affected organs in malarial mice were
also alleviated following inhibition of activin A production. Overall, this preliminary study
suggests that activin A could play an immune modulation role in malaria pathogenesis
through modulation of TNF-α release that benefits host from severe pathological destructions
provoked by intensified inflammatory responses. Further studies are warranted to elucidate
the precise mechanism of immune modulation mediated by activin A and its associated
immune-modulation mediators in regulating the inflammatory responses elicited during
the course of malaria infection.
6.Identification of skin bacterial profiles of early deceased bodies and the relation to post-mortem interval
Chong, C.K. ; Emamjomeh, M. ; Joseph, N. ; Siew, S.F. ; Maeda, T. ; Mustapha, N.A. ; Hoshiko, Y. ; Muthanna, A. ; Amin-Nordin, S.
Tropical Biomedicine 2024;41(No.1):109-117
Post-mortem microbiology (PMM) is an important tool in identifying possible causes of sudden
unexpected death, as an infectious cause is highly suspected. However, contamination is a major problem
in microbiology, and this has increased the difficulty determining the true pathogen that contributes to
death in post-mortem cases. Skin commensals are common contaminants in blood cultures. This study
was conducted to investigate the skin flora on early deceased bodies and observe the bacteria detected
at different post-mortem intervals (PMIs). As blood is usually drawn from the neck and femoral sites for
PMM examination, the two body sites were chosen as the sampling sites. Skin swab samples from the
neck and femoral (n=80) of each early deceased body were collected by sterile cotton swabs. DNA was
extracted from the swabs and then subjected to high-throughput 16S rRNA sequencing by using the
Illumina MiSeq platform. Staphylococcus was found to be the most dominant genus in both neck and
femoral sites. LEfSe results showed that Cutibacterium is significantly different at the neck site while
Corynebacterium is more abundant at femoral site. There are significant differences at genus level
between PMI<5H and PMI>5H at both neck and femoral sites. The findings of the present study may
act as a reference for microbiologists and forensic pathologists when mixed growth or contamination
occurs in post-mortem blood cultures.