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Fulltext MicroRNA in medication related osteonecrosis of the jaw: a review

Mohd Yunus SS, Soh HY, Abdul Rahman M, Peng X, Guo C, Ramli R

Front Physiol, 2023;14:1021429.
PMID: 37179831 DOI: 10.3389/fphys.2023.1021429

Medication related osteonecrosis of the jaw (MRONJ) is a condition caused by inhibition of the osteoclast activity by the anti-resorptive and anti-angiogenic drugs. Clinically, there is an exposure of the necrotic bone or a fistula which fails to heal for more than 8 weeks. The adjacent soft tissue is inflamed and pus may be present as a result of the secondary infection. To date, there is no consistent biomarker that could aid in the diagnosis of the disease. The aim of this review was to explore the literature on the microRNAs (miRNAs) related to medication related osteonecrosis of the jaw, and to describe the role of each miRNA as a biomarker for diagnostic purpose and others. Its role in therapeutics was also searched. It was shown that miR-21, miR-23a, and miR-145 were significantly different in a study involving multiple myeloma patients as well as in a human-animal study while miR-23a-3p and miR-23b-3p were 12- to 14-fold upregulated compared to the control group in an animal study. The role of the microRNAs in these studies were for diagnostics, predictor of progress of MRONJ and pathogenesis. Apart from its potential diagnostics role, microRNAs have been shown to be bone resorption regulator through miR-21, miR-23a and miR-145 and this could be utilized therapeutically.
Fulltext A clustering approach to identify multidimensional poverty indicators for the bottom 40 percent group

Abdul Rahman M, Sani NS, Hamdan R, Ali Othman Z, Abu Bakar A

PLoS One, 2021;16(8):e0255312.
PMID: 34339480 DOI: 10.1371/journal.pone.0255312

The Multidimensional Poverty Index (MPI) is an income-based poverty index which measures multiple deprivations alongside other relevant factors to determine and classify poverty. The implementation of a reliable MPI is one of the significant efforts by the Malaysian government to improve measures in alleviating poverty, in line with the recent policy for Bottom 40 Percent (B40) group. However, using this measurement, only 0.86% of Malaysians are regarded as multidimensionally poor, and this measurement was claimed to be irrelevant for Malaysia as a country that has rapid economic development. Therefore, this study proposes a B40 clustering-based K-Means with cosine similarity architecture to identify the right indicators and dimensions that will provide data driven MPI measurement. In order to evaluate the approach, this study conducted extensive experiments on the Malaysian Census dataset. A series of data preprocessing steps were implemented, including data integration, attribute generation, data filtering, data cleaning, data transformation and attribute selection. The clustering model produced eight clusters of B40 group. The study included a comprehensive clustering analysis to meaningfully understand each of the clusters. The analysis discovered seven indicators of multidimensional poverty from three dimensions encompassing education, living standard and employment. Out of the seven indicators, this study proposed six indicators to be added to the current MPI to establish a more meaningful scenario of the current poverty trend in Malaysia. The outcomes from this study may help the government in properly identifying the B40 group who suffers from financial burden, which could have been currently misclassified.
Tocotrienol-rich fraction from palm oil prevents oxidative damage in diabetic rats

Matough FA, Budin SB, Hamid ZA, Abdul-Rahman M, Al-Wahaibi N, Mohammed J

Sultan Qaboos Univ Med J, 2014 Feb;14(1):e95-e103.
PMID: 24516761

This study was carried out to determine the effects of tocotrienol-rich fraction (TRF) (200 mg/Kg) on biomarkers of oxidative stress on erythrocyte membranes and leukocyte deoxyribonucleic acid (DNA) damage in streptozotocin (STZ)-induced diabetic rats.
Modified Hank's Balanced Salt Solution as a Storage Medium for Avulsed Teeth: In Vitro Assessment of Periodontal Fibroblast Viability

Lee ZJ, Ng SL, Soo E, Abdullah D, Yazid F, Abdul Rahman M, et al.

Dent Traumatol, 2024 Nov 22.
PMID: 39578673 DOI: 10.1111/edt.13010

BACKGROUND/AIM: The optimal storage medium for an avulsed tooth should preserve the viability of periodontal fibroblasts (PDLF) to the highest degree, facilitating the re-attachment of periodontal fibers and improving the prognosis of replantation. This study compared the effect of the PDLF viability in Hank's balanced salt solution (HBSS), supplemented culture medium, that is, Dulbecco's Modified Eagle Medium (DMEM), and four modified HBSS mixtures.
MATERIAL AND METHODS: Periodontal tissues were obtained from extracted human teeth and processed for PDLF culture. The cells were then exposed to six experimental media: (i) HBSS, (ii) HBSS and ascorbic acid (HBSS + Vit C), (iii) HBSS and platelet-derived growth factor (HBSS + PDGF), (iv) a mixture of HBSS, PDGF, and Vit C (HBSS + PDGF + Vit C), (v) HBSS and platelet lysate (HBSS + PL), and (vi) DMEM for 3, 6, 12, and 24 h. A MTT assay was performed to determine the cell viability.
RESULTS: Vitamin C-containing media maintained PDLF viability significantly better than HBSS + PDGF and HBSS + PL at 3, 6, 12, and 24 h (p HBSS+Vit C; HBSS+PDGF+Vit C>HBSS+PL>HBSS+PDGF; HBSS). Although DMEM had the highest cell proliferative effect, it is impractical to be used as a transport medium due to its cost, storage, and availability. The supplementation of Vit C yielded significant cell proliferative effects; hence, HBSS + Vit C can be a better alternative as a storage medium than HBSS.
Fulltext Deregulation of lysophosphatidic acid metabolism in oral cancer promotes cell migration via the up-regulation of COX-2

Abdul Rahman M, Tan ML, Johnson SP, Hollows RJ, Chai WL, Mansell JP, et al.

PeerJ, 2020;8:e10328.
PMID: 33240646 DOI: 10.7717/peerj.10328

Oral squamous cell carcinoma (OSCC) is the sixth most common cancer worldwide and accounts for 300,000 new cases yearly. The five-year survival rate is approximately 50% and the major challenges to improving patient prognosis include late presentation, treatment resistance, second primary tumours and the lack of targeted therapies. Therefore, there is a compelling need to develop novel therapeutic strategies. In this study, we have examined the effect of lysophosphatidic acid (LPA) on OSCC cell migration, invasion and response to radiation, and investigated the contribution of cyclooxygenase-2 (COX-2) in mediating the tumour promoting effects of LPA. Using the TCGA data set, we show that the expression of the lipid phosphate phosphatases (LPP), LPP1 and LPP3, was significantly down-regulated in OSCC tissues. There was no significant difference in the expression of the ENPP2 gene, which encodes for the enzyme autotaxin (ATX) that produces LPA, between OSCCs and control tissues but ENPP2 levels were elevated in a subgroup of OSCCs. To explore the phenotypic effects of LPA, we treated OSCC cell lines with LPA and showed that the lipid enhanced migration and invasion as well as suppressed the response of the cells to irradiation. We also show that LPA increased COX-2 mRNA and protein levels in OSCC cell lines and inhibition of COX-2 activity with the COX-2 inhibitor, NS398, attenuated LPA-induced OSCC cell migration. Collectively, our data show for the first time that COX-2 mediates some of the pro-tumorigenic effects of LPA in OSCC and identifies the ATX-LPP-LPA-COX-2 pathway as a potential therapeutic target for this disease.
Seroprevalence of Leptospirosis in Working Dogs

Lau SF, Wong JY, Khor KH, Roslan MA, Abdul Rahman MS, Bejo SK, et al.

Top Companion Anim Med, 2017 Dec;32(4):121-125.
PMID: 29525230 DOI: 10.1053/j.tcam.2017.12.001

Working dogs are canine animals that have been trained to assist human beings in carrying out various tasks. They help in guarding property, performing rescues, assisting the visually impaired or physically handicapped, searching for drugs, explosives, and others. Leptospirosis is one of the most widespread zoonotic diseases in the world and a commonly occurring disease of the tropics and subtropics. In Malaysia, all working dogs are normally vaccinated with serovars, Pomona, Icterohaemorrhagiae, Canicola, and Grippotyphosa based on protocols recommended from other countries. The duration of immunity in vaccinated dogs for Leptospira can last up to 13 months; however, there is no full crossprotection between the different serovars. Five representative canine units from different government agencies in Malaysia (n = 96 dogs) were recruited in this study. For detection, the microscopic agglutination test was performed by incubating the serum from dogs with various serovars of leptospires, namely, Icterohaemorrhagiae, Canicola, Pomona, Grippotyphosa, Australis, Bataviae, Javanica, Tarassovi, Hebdomadis, Lai, and Pyrogenes. The plasma obtained was used for polymerase chain reaction (PCR) analysis, for the detection of 16S rRNA, and lipL 32 genes of Leptospira. Out of the 96 dogs sampled, only 3 dogs were positive toward serovars, Australis, Bataviae, and Javanica, based on the cutoff point at 1:80. The seroprevalence of canine leptospirosis in this population was 3.1% (n = 3/96). However, all 96 blood samples of working dogs tested negative for both pathogenic and nonpathogenic Leptospira genes. The results revealed that, by vaccination alone, working dogs were not fully protected against leptospirosis and could pose a risk to dog handlers. A preventative and control protocol for leptospirosis is warranted, and its implementation should be monitored and improved accordingly from time to time, in order to maintain a healthy condition in both working dogs and their handlers.
Fulltext Neural correlates of eye contact in face-to-face verbal interaction: An EEG-based study of the extraversion personality trait

Roslan NS, Izhar LI, Faye I, Amin HU, Mohamad Saad MN, Sivapalan S, et al.

PLoS One, 2019;14(7):e0219839.
PMID: 31344061 DOI: 10.1371/journal.pone.0219839

The extraversion personality trait has a positive correlation with social interaction. In neuroimaging studies, investigations on extraversion in face-to-face verbal interactions are still scarce. This study presents an electroencephalography (EEG)-based investigation of the extraversion personality trait in relation to eye contact during face-to-face interactions, as this is a vital signal in social interactions. A sample of healthy male participants were selected (consisting of sixteen more extraverted and sixteen less extraverted individuals) and evaluated with the Eysenck's Personality Inventory (EPI) and Big Five Inventory (BFI) tools. EEG alpha oscillations in the occipital region were measured to investigate extraversion personality trait correlates of eye contact during a face-to-face interaction task and an eyes-open condition. The results revealed that the extraversion personality trait has a significant positive correlation with EEG alpha coherence in the occipital region, presumably due to its relationship with eye contact during the interaction task. Furthermore, the decrease in EEG alpha power during the interaction task compared to the eyes-open condition was found to be greater in the less extraverted participants; however, no significant difference was observed between the less and more extraverted participants. Overall, these findings encourage further research towards the understanding of neural mechanism correlates of the extraversion personality trait-particularly in social interaction.
Fulltext Exploring EEG Effective Connectivity Network in Estimating Influence of Color on Emotion and Memory

Chai MT, Amin HU, Izhar LI, Saad MNM, Abdul Rahman M, Malik AS, et al.

Front Neuroinform, 2019;13:66.
PMID: 31649522 DOI: 10.3389/fninf.2019.00066

Color is a perceptual stimulus that has a significant impact on improving human emotion and memory. Studies have revealed that colored multimedia learning materials (MLMs) have a positive effect on learner's emotion and learning where it was assessed by subjective/objective measurements. This study aimed to quantitatively assess the influence of colored MLMs on emotion, cognitive processes during learning, and long-term memory (LTM) retention using electroencephalography (EEG). The dataset consisted of 45 healthy participants, and MLMs were designed in colored or achromatic illustrations to elicit emotion and that to assess its impact on LTM retention after 30-min and 1-month delay. The EEG signal analysis was first started to estimate the effective connectivity network (ECN) using the phase slope index and expand it to characterize the ECN pattern using graph theoretical analysis. EEG results showed that colored MLMs had influences on theta and alpha networks, including (1) an increased frontal-parietal connectivity (top-down processing), (2) a larger number of brain hubs, (3) a lower clustering coefficient, and (4) a higher local efficiency, indicating that color influences information processing in the brain, as reflected by ECN, together with a significant improvement in learner's emotion and memory performance. This is evidenced by a more positive emotional valence and higher recall accuracy for groups who learned with colored MLMs than that of achromatic MLMs. In conclusion, this paper demonstrated how the EEG ECN parameters could help quantify the influences of colored MLMs on emotion and cognitive processes during learning.
Fulltext Profiling lysophosphatidic acid levels in plasma from head and neck cancer patients

Abdul Rahman M, Mohamad Haron DE, Hollows RJ, Abdul Ghani ZDF, Ali Mohd M, Chai WL, et al.

PeerJ, 2020;8:e9304.
PMID: 32547888 DOI: 10.7717/peerj.9304

Head and neck squamous cell carcinoma (HNSCC) represents a significant world health problem, with approximately 600,000 new cases being diagnosed annually. The prognosis for patients with HNSCC is poor and, therefore, the identification of biomarkers for screening, diagnosis and prognostication would be clinically beneficial. A limited number of studies have used lipidomics to profile lipid species in the plasma of cancer patients. However, the profile and levels of lysophosphatidic acid (LPA) species have not been examined in HNSCC. In this study, a targeted lipidomics approach using liquid chromatography triple quadrupole mass spectrometry (LCMS/MS) was used to analyse the concentration of LPA (16:0 LPA, 18:0 LPA, 18:1 LPA, 18:2 LPA and 20:4 LPA) in the plasma of patients with oral squamous cell carcinoma (OSCC) and nasopharyngeal carcinoma (NPC), together with healthy controls. The levels of three LPA species (18:1 LPA, 18:2 LPA and 20:4 LPA) were significantly lower in the plasma of OSCC patients, whilst the concentrations of all five LPA species tested were significantly lower in plasma from NPC patients. Furthermore, the order of abundance of LPA species in plasma was different between the control and cancer groups, with 16:0 LPA, 18:0 LPA levels being more abundant in OSCC and NPC patients. Medium to strong correlations were observed using all pairs of LPA species and a clear separation of the normal and tumour groups was observed using PCA analysis. In summary, the results of this study showed that the levels of several LPA species in the plasma of patients with OSCC and NPC were lower than those from healthy individuals. Understanding these variations may provide novel insights into the role of LPA in these cancers.