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Implantation of GLP-1 secreting cells fails to recapitulate effects of exogenous GLP-1 mimetics in mice

Vasu S, Hamid MH, McCluskey JT, Irwin N, Flatt PR

Regul. Pept., 2010 Sep 9;164(1):32.
PMID: 26009405 DOI: 10.1016/j.regpep.2010.07.075
Drying kinetics and stabilization of sewage sludge in lagoon in hot climate

Idris A, Yen OB, Hamid MH, Baki AM

Water Sci Technol, 2002;46(9):279-86.
PMID: 12448479

A sludge lagoon has been adopted as a simple and cost effective method for dewatering of sludge. The processes occurring in a sludge lagoon include thickening, dewatering, storage and stabilization; all happening simultaneously. The objective of this study is to determine the dewatering and drying rates at pilot-scale which occur in a lagoon having different design configurations. Two types of sludge lagoons with different initial sludge depth (0.75 m and 0.375 m) were investigated to measure the drying behavior and drying efficiency. The first design is a sludge lagoon with a clay bottom where the dewatering mechanisms are decanting supernatant and evaporation. The second design is a sludge lagoon installed with a sand and underdrains system, where the dewatering mechanisms are filtration or draining and evaporation. Sludge drying kinetic models with high fitness were plotted to describe the sludge drying behavior. Drying of sludge in a sludge lagoon with a clay bottom can best be described by an exponential function. Whereas, drying of sludge in a sludge lagoon with sand and underdrains system followed a logarithmic function. A lagoon designed with sand and underdrains system and having shallower sludge depth was the most efficient. The reduction in volatile solids was lower than 4% during the study period. The drying process proceeded with an increase in dryness and decline in pH value.
Application of immersed MF (IMF) followed by reverse osmosis (RO) membrane for wastewater reclamation: A case study in Malaysia

Ujang Z, Ng KS, Tg Hamzah TH, Roger P, Ismail MR, Shahabudin SM, et al.

Water Sci Technol, 2007;56(9):103-8.
PMID: 18025737

A pilot scale membrane plant was constructed and monitored in Shah Alam, Malaysia for municipal wastewater reclamation for industrial application purposes. The aim of this study was to verify its suitability under the local conditions and environmental constraints for secondary wastewater reclamation. Immersed-type crossflow microfiltration (IMF) was selected as the pretreatment step before reverse osmosis filtration. Secondary wastewater after chlorine contact tank was selected as feed water. The results indicated that the membrane system is capable of producing a filtrate meeting the requirements of both WHO drinking water standards and Malaysian Effluent Standard A. With the application of an automatic backwash process, IMF performed well in hydraulic performance with low fouling rate being achieved. The investigations showed also that chemical cleaning is still needed because of some irreversible fouling by microorganisms always remains. RO treatment with IMF pretreatment process was significantly applicable for wastewater reuse purposes and promised good hydraulic performance.
Fulltext Malaysian Carica papaya L. var. Eksotika: Current Research Strategies Fronting Challenges

Sekeli R, Hamid MH, Razak RA, Wee CY, Ong-Abdullah J

Front Plant Sci, 2018;9:1380.
PMID: 30279695 DOI: 10.3389/fpls.2018.01380

Carica papaya L. or commonly known as papaya, is a major tropical crop consumed worldwide either as a vegetable or fresh fruit or processed products. In Malaysia, papaya was initially planted as a smallholder crop throughout the country. Eventually after 15 years of breeding and selection, a new variety, named C. papaya L. var. Eksotika, was released by the Malaysian Agricultural Research and Development Institute (MARDI) in 1987. This event changed the outlook of papaya planting from a smallholder crop to a plantation crop. Despite the blooming papaya business, the industry faced various disease issues that jeopardize its future. The most devastating was the papaya dieback disease, which affected approximately 800 hectares of plantation, destroyed approximately 1 million trees nationwide with total losses estimated at US$ 58 million. Even though Eksotika is a favored commercial variety with good eating and aesthetic quality fruit, its potential for more lucrative distant markets is tarnished with its short-shelf life fruits. Several strategies had been reported to address the challenges faced by Eksotika specifically against the dieback disease and the fruit's short shelf-life. This review focuses on C. papaya L. var. Eksotika particularly on the strategies to address the challenges faced in order to sustain the economic value of this crop plant, which had contributed significantly to the Malaysian economy.
Fulltext Analysis of MAP kinase MPK4/MEKK1/MKK genes of Carica papaya L. comparative to other plant homologues

Hamid MH, Rozano L, Yeong WC, Abdullah JO, Saidi NB

Bioinformation, 2017;13(2):31-41.
PMID: 28642634 DOI: 10.6026/97320630013031

Mitogen-activated protein kinase 4 (MPK4) interacts with the (Mitogen-activated protein kinase kinase kinase 1) MEKK1/ Mitogenactivated protein kinase kinase 1 (MKK1)/ Mitogen-activated protein kinase kinase 2 (MKK2) complex to affect its function in plant development or against pathogen attacks. The KEGG (Kyoto Encyclopedia of Genes and Genomes) network analysis of Arabidopsis thaliana revealed close interactions between those four genes in the same plant-pathogen interaction pathway, which warrants further study of these genes due to their evolutionary conservation in different plant species. Through targeting the signature sequence in MPK4 of papaya using orthologs from Arabidopsis, the predicted sequence of MPK4 was studied using a comparative in silico approach between different plant species and the MAP cascade complex of MEKK1/MKK1/MKK2. This paper reported that MPK4 was highly conserved in papaya with 93% identical across more than 500 bases compared in each species predicted. Slight variations found in the MEKK1/MKK1/MKK2 complex nevertheless still illustrated sequence similarities between most of the species. Localization of each gene in the cascade network was also predicted, potentiating future functional verification of these genes interactions using knock out or/and gene silencing tactics.
Recombinase-Aided Loop-Mediated Isothermal Amplification on Human Plasmodium knowlesi

Lai MY, Abdul Hamid MH, Jelip J, Mudin RN, Lau YL

Am J Trop Med Hyg, 2024 Apr 03;110(4):648-652.
PMID: 38412548 DOI: 10.4269/ajtmh.23-0572

Loop-mediated isothermal amplification (LAMP) is a nucleic acid amplification technique that can amplify specific nucleic acids at a constant temperature (63-65°C) within a short period (<1 hour). In this study, we report the utilization of recombinase-aided LAMP to specifically amplify the 18S sRNA of Plasmodium knowlesi. The method was built on a conventional LAMP assay by inclusion of an extra enzyme, namely recombinase, into the master mixture. With the addition of recombinase into the LAMP assay, the assay speed was executed within a time frame of less than 28 minutes at 65°C. We screened 55 P. knowlesi samples and 47 non-P. knowlesi samples. No cross-reactivity was observed for non-P. knowlesi samples, and the detection limit for recombinase-aided LAMP was one copy for P. knowlesi after LAMP amplification. It has been reported elsewhere that LAMP can be detected through fluorescent readout systems. Although such systems result in considerable limits of detection, the need for sophisticated equipment limits their use. Hence, we used here a colorimetric detection platform for the evaluation of the LAMP assay's performance. This malachite green-based recombinase-aided LAMP assay enabled visualization of results with the naked eye. Negative samples were observed by a change in color from green to colorless, whereas positive samples remained green. Our results demonstrate that the LAMP assay developed here is a convenient, sensitive, and useful diagnostic tool for the rapid detection of knowlesi malaria parasites. This method is suitable for implementation in remote healthcare settings, where centralized laboratory facilities, funds, and clinicians are in short supply.
Fulltext Prevalence of Asymptomatic and/or Low-Density Malaria Infection among High-Risk Groups in Peninsular Malaysia

Noordin NR, Lee PY, Mohd Bukhari FD, Fong MY, Abdul Hamid MH, Jelip J, et al.

Am J Trop Med Hyg, 2020 09;103(3):1107-1110.
PMID: 32618263 DOI: 10.4269/ajtmh.20-0268

Asymptomatic and/or low-density malaria infection has been acknowledged as an obstacle to achieving a malaria-free country. This study aimed to determine the prevalence of asymptomatic and/or low-density malaria infection in previously reported malarious localities using nested PCR in four states, namely, Johor, Pahang, Kelantan, and Selangor, between June 2019 and January 2020. Blood samples (n = 585) were collected and were extracted using a QIAamp blood kit. The DNA was concentrated and subjected to nested PCR. Thin and thick blood smears were examined as well. Of the 585 samples collected, 19 were positive: 10 for Plasmodium knowlesi, eight for Plasmodium vivax, and one for Plasmodium ovale. Asymptomatic and/or low-density malaria infection is a threat to malaria elimination initiatives. Eliminating countries should develop guidance policy on the importance of low-density malaria infection which includes detection and treatment policy.
Fulltext A Randomized Controlled Trial Comparing Wide-Awake Local Anesthesia With No Tourniquet (WALANT) to General Anesthesia in Plating of Distal Radius Fractures With Pain and Anxiety Level Perception

Abd Hamid MH, Abdullah S, Ahmad AA, Narin Singh PSG, Soh EZF, Liu CY, et al.

Cureus, 2021 Jan 23;13(1):e12876.
PMID: 33633905 DOI: 10.7759/cureus.12876

INTRODUCTION: Distal end radius fractures are common fractures commonly treated with an option of open reduction and plating. Traditionally, plating is performed under general anesthesia (GA) or regional block. Recently, a new technique of plating under wide-awake local anesthesia with no tourniquet (WALANT) has been introduced. We aim to compare the preoperative anxiety level, intraoperative pain scores, post-operative pain scores, operating time, blood loss and clinical outcome of distal end radius plating with WALANT versus GA with tourniquet.
METHODS: We conducted a randomized controlled study on patients with closed fracture of the distal end of the radius requiring open reduction and plating from January 2019 till April 2020. We recruited 65 patients (33 patients in the WALANT group and 32 patients in the GA group). Randomization was done via block randomization. Data were collected to evaluate preoperative anxiety using the Amsterdam Preoperative Anxiety and Information Scale (APAIS) score, intraoperative pain score during injection (baseline) (V1), 10 minutes after injection (V2), during incision (V3), during gentle manipulation (V4), during aggressive manipulation (V5) and during first drilling of screw (V6), blood loss, duration of surgery and post-operative pain score. Additionally, intraoperative visual analog scale (VAS) score was obtained in the WALANT group. At three weeks, six weeks, three months and six months after operation, the Quick Disabilities of Arm, Shoulder and Hand (QuickDASH) scores and range of motion (ROM) of the wrists were obtained.
RESULTS: The average age in the WALANT group was 47.19 (range, 36-64) years and GA group was 49.48 (range, 38-60) years. The mean APAIS score obtained was 7.78 (WALANT group) and 7.36 (GA group) with no statistical difference. For intraoperative VAS, only during V4 and V5 were the scores 1/10; otherwise at all other phases, the VAS score was 0. The average time for surgery was statistically longer in the WALANT group (61.22 minutes) compared to the GA group (55.33 minutes) (p = 0.003). There was no statistical difference in mean blood loss in both groups. The average post-operative VAS showed statistical significance only at 1 hour and 12 hours post-operation with no statistical difference at 2 and 24 hours post-operation. There was no difference in the post-operative ROM including wrist flexion, extension, supination and pronation for both groups up to six months' follow-up.
CONCLUSION: There was no statistically significant difference in terms of preoperative anxiety level, intraoperative and post-operative VAS score, amount of blood loss and clinical outcome in both groups for plating of the distal end radius. However, the operating time was slightly longer in the WALANT group. We conclude that distal radius plating under WALANT has similar outcomes to GA. In centres with limited resources, WALANT offers a safe, reliable and cheaper option, reserving GA time for head, abdominal and thoracic surgery.
Fulltext DRD and GRIN2B polymorphisms and their association with the development of impulse control behaviour among Malaysian Parkinson's disease patients

Zainal Abidin S, Tan EL, Chan SC, Jaafar A, Lee AX, Abd Hamid MH, et al.

BMC Neurol, 2015;15:59.
PMID: 25896831 DOI: 10.1186/s12883-015-0316-2

Impulse control disorder (ICD) and behaviours (ICB) represent a group of behavioural disorders that have become increasingly recognised in Parkinson's disease (PD) patients who previously used dopaminergic medications, particularly dopamine agonists and levodopa. It has been suggested that these medications can lead to the development of ICB through the abnormal modulation of dopaminergic transmission and signalling in the mesocorticolimbic dopaminergic system. Several studies have reported an association between polymorphisms in the dopamine receptor (DRD) and N-methyl-D-aspartate 2B (GRIN2B) genes with the development of ICB in PD (PD-ICB) patients. Thus, this study aimed to investigate the association of selected polymorphisms within the DRD and GRIN2B genes with the development of ICB among PD patients using high resolution melt (HRM) analysis.