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ONIOM and ab-initio calculations on the mechanism of uncatalyzed peptide bond formation

Monajemi H, Daud MN, Mohd Zain S, Wan Abdullah WA

Biochem. Cell Biol., 2012 Dec;90(6):691-700.
PMID: 23016605 DOI: 10.1139/o2012-027

Finding a proper transition structure for the peptide bond formation process can lead one to a better understanding of the role of ribosome in catalyzing this reaction. Using computer simulations, we performed the potential energy surface scan on the ester bond dissociation of P-site aminoacyl-tRNA and the peptide bond formation of P-site and A-site amino acids. The full fragments of initiator tRNA(i)(met) and elongator tRNA(phe) are attached to both cognate and non-cognate amino acids as the P-site substrate. The A-site amino acid for all four calculations is methionine. We used ONIOM calculations to reduce the computational cost. Our study illustrates the reduced rate of peptide bond formation for misacylated tRNA(i)(met) in the absence of ribosomal bases. The misacylated elongator tRNA(phe), however, did not show any difference in its PES compared with that for the phe-tRNA(phe). This demonstrates the structural specification of initiator tRNA(i)(met) for the amino acids side chain.
Fulltext Structural and optical characterization of metal tungstates (MWO4; M=Ni, Ba, Bi) synthesized by a sucrose-templated method

M Zawawi SM, Yahya R, Hassan A, Mahmud HN, Daud MN

Chem Cent J, 2013;7(1):80.
PMID: 23634962 DOI: 10.1186/1752-153X-7-80

Metal tungstates have attracted much attention due to their interesting structural and photoluminescence properties. Depending on the size of the bivalent cation present, the metal tungstates will adopt structures with different phases. In this work, three different phases of metal tungstates MWO4 (M= Ba, Ni and Bi) were synthesized via the sucrose templated method.
Fulltext Characterization of CdTe films deposited at various bath temperatures and concentrations using electrophoretic deposition

Daud MN, Zakaria A, Jafari A, Ghazali MS, Abdullah WR, Zainal Z

Int J Mol Sci, 2012;13(5):5706-14.
PMID: 22754325 DOI: 10.3390/ijms13055706

CdTe film was deposited using the electrophoretic deposition technique onto an ITO glass at various bath temperatures. Four batch film compositions were used by mixing 1 to 4 wt% concentration of CdTe powder with 10 mL of a solution of methanol and toluene. X-ray Diffraction analysis showed that the films exhibited polycrystalline nature of zinc-blende structure with the (111) orientation as the most prominent peak. From the Atomic Force Microscopy, the thickness and surface roughness of the CdTe film increased with the increase of CdTe concentration. The optical energy band gap of film decreased with the increase of CdTe concentration, and with the increase of isothermal bath temperature. The film thickness increased with respect to the increase of CdTe concentration and bath temperature, and following, the numerical expression for the film thickness with respect to these two variables has been established.
The role of initiator tRNAimet in fidelity of initiation of protein synthesis

Monajemi H, Omar NY, Daud MN, Zain SM, Abdullah WA

Nucleosides Nucleotides Nucleic Acids, 2011 Sep;30(9):726-39.
PMID: 21902474 DOI: 10.1080/15257770.2011.605780

The proper arrangement of amino acids in a protein determines its proper function, which is vital for the cellular metabolism. This indicates that the process of peptide bond formation requires high fidelity. One of the most important processes for this fidelity is kinetic proofreading. As biochemical experiments suggest that kinetic proofreading plays a major role in ensuring the fidelity of protein synthesis, it is not certain whether or not a misacylated tRNA would be corrected by kinetic proofreading during the peptide bond formation. Using 2-layered ONIOM (QM/MM) computational calculations, we studied the behavior of misacylated tRNAs and compared the results with these for cognate aminoacyl-tRNAs during the process of peptide bond formation to investigate the effect of nonnative amino acids on tRNAs. The difference between the behavior of initiator tRNA(i) (met) compared to the one for the elongator tRNAs indicates that only the initiator tRNA(i) (met) specifies the amino acid side chain.
Fulltext Children's eating behaviour: A comparison between normal, overweight and obese children

Kimin LS, Liew Sat Lin C, Avoi R, Hayati F, Mohd Daud MN, Mandrinos S, et al.

Ann Med Surg (Lond), 2022 Dec;84:104890.
PMID: 36536714 DOI: 10.1016/j.amsu.2022.104890

BACKGROUND: Childhood obesity has become a major global health concern and has been increasing dramatically over the years. Previous study has shown that specific eating behaviours may have been associated with obesity especially under-responsiveness to internal satiety cues and over-responsiveness to external food cues such as the taste, smell, availability and emotions. However, there is still inadequate number of studies present to describe the association between the children's body mass index (BMI) and their eating behaviours, especially in Sabah, Malaysia. Therefore, the objective of this study is to established the association between the children's eating behaviours with their nutritional status based on their body mass index.
MATERIALS AND METHODS: A cross-sectional study involving 484 children aged 6-12 years old was conducted in Kota Kinabalu, which is a developing urban area in Sabah. The children were recruited from five primary schools that were selected based on multistage stratified and convenience sampling method. Sociodemographic details and anthropometric measures both parents and children, and eating behaviours of children were assessed using Children Eating Behaviour Questionnaires (CEBQ). Age-adjusted BMI z-scores were then calculated according to the World Health Organization recommendations to assess nutritional status.
RESULTS: The prevalence of childhood obesity among children aged 6-12 years old is 13.2%. The mean scores of 'Food Approach' subscales from the CEBQ showed higher mean score in overweight and obese groups as compared to the mean score in normal weight group. The mean scores of 'Food Avoidance' subscales showed lower mean score in overweight and obese groups as compared to mean score in normal weight group.
CONCLUSION: This study provides evidence that childhood obesity is yet to be a prevalent health problem in a developing urban area considering the "Food approach" subscales were positively associated with the excess weight in children.
Private troubles to public issue: empowering communities to reduce alcohol-related harm in Sabah, Malaysia

Lasimbang HB, Shoesmith W, Mohd Daud MN, Kaur N, Jin MC, Singh J, et al.

Health Promot Int, 2017 02 01;32(1):122-129.
PMID: 28180267 DOI: 10.1093/heapro/dav090

Summary: Alcohol is the number three contributor to the burden of disease worldwide so must remain a priority health promotion issue internationally. Malaysia is a Muslim country and alcohol-related harm was not seen as a priority until recently, because it only affects a minority of the population. Sabah has more than 30 different ethnic groups, and alcohol has a traditional role in the cultural practices of many of these groups. In 2009, the Intervention Group for Alcohol Misuse (IGAM) was formed, under the umbrella of Mercy Malaysia by a group of healthcare workers, academics, members of the Clergy and people who were previously alcohol-dependent concerned about the harmful effects of excessive alcohol consumption. IGAM in collaboration with other bodies have organized public seminars, visited villages and schools, encouraged the formation of a support group and trained healthcare professionals in health promotion intervention. The focus later changed to empowering communities to find solutions to alcohol-related harm in their community in a way which is sensitive to their culture. A standard tool-kit was developed using WHO materials as a guide. Village committees were formed and adapted the toolkit according to their needs. This strategy has been shown to be effective, in that 90% of the 20 committees formed are actively and successfully involved in health promotion to reduce alcohol-related harm in their communities.
Fulltext Successful pregnancy in morbidly obese lady with polycystic ovary syndrome after bariatric surgery: A case report

Pg Baharuddin DM, Leik NKO, Hayati F, Mohd Daud MN, See E, Sharif SZ, et al.

Int J Surg Case Rep, 2021 Aug;85:106235.
PMID: 34330067 DOI: 10.1016/j.ijscr.2021.106235

INTRODUCTION: Obesity has been proven to have adverse effects on fertility and is one of the predisposing factors for delay in pregnancy even with the use of assisted reproductive technique. There are many pathways in which obesity can affect fertility such as anovulation, poor implantation and low-quality oocyte.
CASE PRESENTATION: We report a case of a 40-year-old lady with primary infertility for six years with underlying polycystic ovary syndrome (PCOS) and BMI 45.7 whom was successfully conceived twice following bariatric surgery procedure in which reduction of 70% of her BMI prior to bariatric surgery lead to her spontaneous conception without fertility intervention and successful live birth.
CLINICAL DISCUSSION: Obese PCOS needs multidisciplinary approaches which include weight loss program such as dietary advice, exercise intervention as part of preliminary treatment prior to ovulation induction and counselling.
CONCLUSION: Bariatric surgery has been a mainstay treatment in patients with morbid obesity and those with BMI more than 35 associated with obesity related problems such as joint pain, hypertension or diabetes mellitus. Bariatric surgery such as laparoscopic sleeve gastrectomy should be considered more often in contrast to lifestyle modification for morbidly obese lady with PCOS and infertility prior to the use of standard ovulation induction regime for treating infertility.
Fulltext Bariatric surgery and its impact on fertility, pregnancy and its outcome: A narrative review

Pg Baharuddin DM, Payus AO, Abdel Malek Fahmy EH, Sawatan W, Than WW, Abdelhafez MM, et al.

Ann Med Surg (Lond), 2021 Dec;72:103038.
PMID: 34849219 DOI: 10.1016/j.amsu.2021.103038

Bariatric procedures are on the rise as a surgical treatment for morbid obesity. In reproductive age of women, bariatric surgeries will improve factors related to anovulation and lead to spontaneous fertility. Spontaneous pregnancy can happen within a year after bariatric surgery due to higher level of sex hormone binding globulin and follicular stimulating hormone and reduction in androgens level. Reduction of length of follicular phase of menstrual cycle was reported and contribute to improved ovulatory status. The major impact to pregnant women is development of small for gestational age babies due to persistent weight loss but this can be minimized by avoiding pregnancies too soon after bariatric surgery and good nutrition supplement. Risk of developing gestational diabetes mellitus and preeclampsia reduced among post bariatric surgery compared to no surgery. Another benefit observed are reduction in the risk of caesarean section and admission to neonatal intensive care unit. There are no significant changes in composition of breast milk in postpartum women without bariatric surgery and with women whom undergone surgery although more study needed to evaluate this effect. Good prenatal care, micronutrient supplement during antenatal follow up and close supervision from expert managing this pregnancy are essential component to ensure good outcome to mothers and their newborn.
Venous thromboembolism and pregnancy: A review of the literature

Abdelhafez MM, Ahmed KA, Daud MN, Eldiasty AM, Amri MF, Jeffree MS, et al.

Afr J Reprod Health, 2023 May;27(5):81-94.
PMID: 37584933 DOI: 10.29063/ajrh2023/v27i5.8

This review aims to provide the mother carers with the most recent evidence-based guidelines in the context of managing of pregnancy-associated VTE, where an extensive search through the medical journals addressing the topic including the medical database such as Pubmed, Medline, Sience direct,Embase and others using the title and key-words in order to gather the most concerned as well as the up-to-date publications concerned with the problem under research, the search resulted in recognising pregnancy as a significant risk factor for the development of VTE, both during the prenatal and postnatal periods, with an estimated increased likelihood risk of five and sixty times, respectively and concluded that venous thromboembolism (VTE) is one of the leading causes of maternal mortality hence, all pregnant women should be assessed for the risk of developing the condition as early as possible (when scheduling a booking antenatal appointment) or even in the pre-pregnancy clinic.
Fulltext Colorectal cancer and potential predictors of never screened for faecal occult blood test: a narrative review

Sazali MF, Rahim SSSA, Hayati F, Mohd Daud MN, Avoi R, Omar A, et al.

J Public Health Res, 2021 Aug 04;11(1).
PMID: 34351098 DOI: 10.4081/jphr.2021.2377

Colorectal cancer (CRC) is a major public health threat. Therefore, CRC screening uptake has been a focus with the established precancerous lesion and the strong association of early detection with staging and survival of the disease. However, CRC screening is relatively low in many countries. This article briefly discussed the current situation of CRC, recommendations, and current uptake of CRC screening in various countries. Besides that, this article also highlights the potential factors that help to predict the CRC screening uptake worldwide. Identification of those factors could guide policymakers to develop an effective strategy to improve the CRC screening uptake and ultimately improve the health outcome of the population.