Displaying publications 41 - 60 of 339 in total

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  1. Fulltext Role of the Neurons, Astrocytes and Particle-Wave Duality in Conventional Electromagnetic Field, Plasma Brain Dynamics and Quantum Brain Dynamics
    Idris Z, Zakaria Z, Abdullah JM
    Malays J Med Sci, 2021 Dec;28(6):1-7.
    PMID: 35002485 DOI: 10.21315/mjms2021.28.6.1
    The brain is regarded as the most complex anatomical structure in the human body that executes various functions. The electromagnetic brainwaves or energy with its discrete network is commonly thought of as the sole contributor to various brain functions. However, the discrete pattern of the brain network seems insufficient to explain consciousness, binding problems in neural communication, brain heat, psychiatric manifestations and higher-order of thinking. Therefore, it seems that the brain must possess additional energy for it to have a much higher degree of functional freedom. Plasma brain dynamics (PBD) and quantum brain dynamics (QBD) are two hypothetical brain energies that have a strong scientific basis to exist together with the conventional brain electromagnetic energy. The presence of these energies may explain the puzzling brain functions, thus creating an opportunity to correct any abnormalities arising from them.
  2. Fulltext History of Neurosurgery in Malaysia: The Past, Present and Future
    Abdullah FC, Zakaria Z, Thambinayagam HC, Kandasamy R, Alias A, Abu Bakar A, et al.
    Malays J Med Sci, 2021 Dec;28(6):129-185.
    PMID: 35002497 DOI: 10.21315/mjms2021.28.6.13
    The history of neurosurgery in Malaysia traces back to 1962 and is filled with stories of vibrant and humble neurosurgeons who have dedicated their life to patients and professions. The early development of neurological and neurosurgical services begins from the establishment of the neurosurgery unit at Hospital Kuala Lumpur (HKL), followed by the foundation of the Tunku Abdul Rahman Neuroscience Institute (IKTAR). Due to the exponentially increased demand for the care of neurosurgical patients, many universities and government hospitals have opened their neurosurgical units. In 2001, the formal residency training programme (USM Masters in Neurosurgery) started and since then has produced qualified neurosurgeons that empowered and shaped the present generation. The formation of the Neurosurgical Association of Malaysia (NAM) is another turning point towards bidirectional collaboration with the World Federation of Neurosurgical Societies (WFNS). Many opportunities were created for educational activities and the expansion of subspecialties in neurosurgery. This article describes the impact of the past neurosurgeons and the endeavors that they had gone through; the present neurosurgeons who pioneered the current neurosurgical services in Malaysia, and the future neurosurgeons that will continue the legacy and bring neurosurgery further ahead in this country.
  3. Fulltext Protective and Therapeutic Effects of Orlistat on Metabolic Syndrome and Oxidative Stress in High-Fat Diet-Induced Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD) in Rats: Role on Nrf2 Activation
    Zakaria Z, Othman ZA, Bagi Suleiman J, Jalil NAC, Ghazali WSW, Mohamed M
    Vet Sci, 2021 Nov 12;8(11).
    PMID: 34822647 DOI: 10.3390/vetsci8110274
    Metabolic dysfunction-associated fatty liver disease (MAFLD) is an excessive buildup of liver lipids closely associated with various kinds of undesirable metabolic effects and oxidative stress. We aimed to investigate the protective and therapeutic effects of orlistat on metabolic syndrome and oxidative stress parameters in high-fat diet (HFD) induced-MAFLD rats. Twenty-four male Sprague-Dawley rats were randomly divided into four groups (n = 6/group), i.e., Normal control (N), HFD, HFD + orlistat (HFD + O) (10 mg/kg/day administered concomitantly for 12 weeks as a protective model), and obese+orlistat (OB + O) (10 mg/kg/day administered 6 weeks after induction of obesity as a therapeutic model) groups. After 12 weeks, the HFD group had significantly increased Lee obesity index, serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, total cholesterol, triglyceride, low-density lipoprotein levels, liver total cholesterol and triglyceride levels, insulin resistance and non-alcoholic steatohepatitis (NASH) together with decreased serum high-density lipoprotein level. Additionally, the HFD group also showed increased Nrf2 translocation to the nucleus with high Keap1 expression and increased liver oxidative stress parameters. Orlistat significantly improved all these alterations in HFD rats. We demonstrated that orlistat might have protective and therapeutic effects against HFD-induced MAFLD rats by its activation on Nrf2 signaling pathway, which subsequently improved metabolic syndrome and oxidative stress parameters.
  4. Fulltext Role of imaging in managing lateral trocar site incisional hernia after abdominoperineal resection
    Aimanan K, Mohd Nor MR, Ling W, Che Ghazali K, Ahmad Hamidi AJ, Hayati F, et al.
    Radiol Case Rep, 2021 Nov;16(11):3457-3460.
    PMID: 34527123 DOI: 10.1016/j.radcr.2021.08.031
    Trocar site incisional hernia (TSIH) is an unpleasant complication of laparoscopic surgery. A 70-year-old male with low rectal carcinoma underwent a laparoscopic abdominoperineal resection after completion of neoadjuvant radiotherapy. The postoperative recovery was smooth; however, he developed abdominal distension and pain over the previous drain site after removal on day 3. In view of diagnostic ambiguity, an imaging tool was requested as an adjunct to further management. Computed tomography of the abdomen showed small bowel obstruction secondary to herniated ileal loops passing through the right iliac fossa anterior abdominal wall defect at the previous drainage site. An exploration was made and the rectus defect was closed using a non-absorbable suture.
  5. Fulltext Detection of Mycobacterium tuberculosis complex antibodies in free-ranged wild boar and wild macaques in selected districts in Selangor and reevaluation of tuberculosis serodetection in captive Asian elephants in Pahang, Peninsular Malaysia
    Lekko YM, Che-Amat A, Ooi PT, Omar S, Mohd-Hamdan DT, Linazah LS, et al.
    J Vet Med Sci, 2021 Oct 31;83(11):1702-1707.
    PMID: 34544936 DOI: 10.1292/jvms.21-0144
    Tuberculosis (TB) is a chronic inflammatory and zoonotic disease caused by Mycobacterium tuberculosis complex (MTBC) members, affecting several domestic animals, wildlife species and humans. The preliminary investigation was aimed to detect antibody against MTBC among indigenous wildlife which are free-ranged wild boar, free-ranged wild macaques and captive Asian elephants in selected areas of Selangor and elephant conservation centre in Pahang, respectively. The results indicate that MTBC serodetection rate in wild boar was 16.7% (7.3-33.5 at 95% confidence interval (CI)) using an in-house ELISA bPPD IgG and 10% (3.5-25.6 at 95% CI) by DPP®VetTB assay, while the wild macaques and Asian elephant were seronegative. The univariate analysis indicates no statistically significant difference in risk factors for sex and age of wild boar but there was a significant positive correlation (P<0.05) between bovine TB in dairy cattle and wild boar seropositivity in the Sepang district.
  6. Fulltext Comprehensive analysis of mutations and clonal evolution patterns in a cohort of patients with cytogenetically normal acute myeloid leukemia
    Mat Yusoff Y, Ahid F, Abu Seman Z, Abdullah J, Kamaluddin NR, Esa E, et al.
    Mol Cytogenet, 2021 Sep 24;14(1):45.
    PMID: 34560908 DOI: 10.1186/s13039-021-00561-2
    BACKGROUND: Relapsed acute myeloid leukemia (AML) is associated with the acquisition of additional somatic mutations which are thought to drive phenotypic adaptability, clonal selection and evolution of leukemic clones during treatment. We performed high throughput exome sequencing of matched presentation and relapsed samples from 6 cytogenetically normal AML (CN-AML) patients treated with standard remission induction chemotherapy in order to contribute with the investigation of the mutational landscape of CN-AML and clonal evolution during AML treatment.

    RESULT: A total of 24 and 32 somatic variants were identified in presentation and relapse samples respectively with an average of 4.0 variants per patient at presentation and 5.3 variants per patient at relapse, with SNVs being more frequent than indels at both disease stages. All patients have somatic variants in at least one gene that is frequently mutated in AML at both disease presentation and relapse, with most of these variants are classic AML and recurrent hotspot mutations including NPM1 p.W288fs, FLT3-ITD, NRAS p.G12D and IDH2 p.R140Q. In addition, we found two distinct clonal evolution patterns of relapse: (1) a leukemic clone at disease presentation acquires additional mutations and evolves into the relapse clone after the chemotherapy; (2) a leukemic clone at disease presentation persists at relapse without the addition of novel somatic mutations.

    CONCLUSIONS: The findings of this study suggest that the relapse-initiating clones may pre-exist prior to therapy, which harbor or acquire mutations that confer selective advantage during chemotherapy, resulting in clonal expansion and eventually leading to relapse.

  7. Fulltext Enhanced Directed Random Walk for the Identification of Breast Cancer Prognostic Markers from Multiclass Expression Data
    Nies HW, Mohamad MS, Zakaria Z, Chan WH, Remli MA, Nies YH
    Entropy (Basel), 2021 Sep 20;23(9).
    PMID: 34573857 DOI: 10.3390/e23091232
    Artificial intelligence in healthcare can potentially identify the probability of contracting a particular disease more accurately. There are five common molecular subtypes of breast cancer: luminal A, luminal B, basal, ERBB2, and normal-like. Previous investigations showed that pathway-based microarray analysis could help in the identification of prognostic markers from gene expressions. For example, directed random walk (DRW) can infer a greater reproducibility power of the pathway activity between two classes of samples with a higher classification accuracy. However, most of the existing methods (including DRW) ignored the characteristics of different cancer subtypes and considered all of the pathways to contribute equally to the analysis. Therefore, an enhanced DRW (eDRW+) is proposed to identify breast cancer prognostic markers from multiclass expression data. An improved weight strategy using one-way ANOVA (F-test) and pathway selection based on the greatest reproducibility power is proposed in eDRW+. The experimental results show that the eDRW+ exceeds other methods in terms of AUC. Besides this, the eDRW+ identifies 294 gene markers and 45 pathway markers from the breast cancer datasets with better AUC. Therefore, the prognostic markers (pathway markers and gene markers) can identify drug targets and look for cancer subtypes with clinically distinct outcomes.
  8. Fulltext Rapid detection of colistin-resistant Enterobacterales using the resazurin reduction-based assay
    Karim MR, Zakaria Z, Hassan L, Ahmad NI, Faiz NM, Garba B
    J Glob Antimicrob Resist, 2021 09;26:154-156.
    PMID: 34118481 DOI: 10.1016/j.jgar.2021.05.012
  9. Fulltext Bee bread mitigates downregulation of steroidogenic genes, decreased spermatogenesis, and epididymal oxidative stress in male rats fed with high-fat diet
    Suleiman JB, Abu Bakar AB, Noor MM, Nna VU, Othman ZA, Zakaria Z, et al.
    Am J Physiol Endocrinol Metab, 2021 Sep 01;321(3):E351-E366.
    PMID: 34229480 DOI: 10.1152/ajpendo.00093.2021
    The pituitary-gonadal axis plays an important role in steroidogenesis and spermatogenesis, and by extension, fertility. The aim of this study was to investigate the protective role of bee bread, a natural bee product, against obesity-induced decreases in steroidogenesis and spermatogenesis. Thirty-two adult male Sprague-Dawley rats weighing between 200 and 300 g were divided into four groups (n = 8/group), namely: normal control (NC), high-fat diet (HFD), HFD plus bee bread administered concurrently for 12 wk (HFD + B), HFD plus orlistat administered concurrently for 12 wk (HFD + O) groups. Bee bread (0.5 g/kg) or orlistat (10 mg/kg/day) was suspended in distilled water and given by oral gavage daily for 12 wk. Levels of follicle-stimulating hormone, luteinizing hormone, testosterone, and adiponectin, as well as sperm count, motility, viability, normal morphology, and epididymal antioxidants decreased, whereas levels of leptin, malondialdehyde, and sperm nDNA fragmentation increased significantly in the HFD group relative to the NC group. There were significant decreases in the testicular mRNA transcript levels of androgen receptor, luteinizing hormone receptor, steroidogenic acute regulatory protein, cytochrome P450 enzyme, 3β-hydroxysteroid dehydrogenase (HSD) and 17β-HSD in the testes of the HFD group. Furthermore, mount, intromission and ejaculatory latencies increased, and penile cGMP level decreased significantly in the HFD group. Supplementation with bee bread significantly reduced leptin level and increased adiponectin level, enhanced sperm parameters and reduced sperm nDNA fragmentation, upregulated the levels of steroidogenic genes and proteins in HFD-induced obese male rats. Bee bread improved steroidogenesis and spermatogenesis by upregulating steroidogenic genes. Therefore, bee bread may be considered as a potential supplementation to protect against infertility in overweight men or men with obesity.NEW & NOTEWORTHY The high-fat diet utilized in the present study induced obesity in the male rats. Bee bread supplementation mitigated impaired steroidogenesis, spermatogenesis, mating behavior, and fertility potential by counteracting the downregulation of steroidogenic genes, thus increasing testosterone levels and suppressing epididymal oxidative stress. These benefits may be due to the abundance of phenolic and flavonoid compounds in bee bread.
  10. Commentary: Radiofrequency Ablation for Movement Disorders: Risk Factors for Intracerebral Hemorrhage, a Retrospective Analysis
    Zakaria Z, Ghani ARI, Idris Z, Fitzrol DN, Ang SY, Abdullah JM
    Oper Neurosurg (Hagerstown), 2021 08 16;21(3):E221-E223.
    PMID: 34114025 DOI: 10.1093/ons/opab190
  11. Fulltext Chemical Profile, Antioxidant Properties and Antimicrobial Activities of Malaysian Heterotrigona itama Bee Bread
    Suleiman JB, Mohamed M, Abu Bakar AB, Nna VU, Zakaria Z, Othman ZA, et al.
    Molecules, 2021 Aug 15;26(16).
    PMID: 34443531 DOI: 10.3390/molecules26164943
    The aim of the study was to determine the chemical profile, antioxidant properties and antimicrobial activities of Heterotrigona itama bee bread from Malaysia. The pH, presence of phytochemicals, antioxidant properties, total phenolic content (TPC) and total flavonoid content (TFC), as well as antimicrobial activities, were assessed. Results revealed a decrease in the pH of bee bread water extract (BBW) relative to bee bread ethanolic extract (BBE) and bee bread hot water extract (BBH). Further, alkaloids, flavonoids, phenols, tannins, saponins, terpenoids, resins, glycosides and xanthoproteins were detected in BBW, BBH and BBE. Also, significant decreases in TPC, TFC, DPPH activity and FRAP were detected in BBW relative to BBH and BBE. We detected phenolic acids such as gallic acid, caffeic acid, trans-ferulic acid, trans 3-hydroxycinnamic acid and 2-hydroxycinnamic acid, and flavonoids such as quercetin, kaempferol, apigenin and mangiferin in BBE using high-performance liquid chromatography analysis. The strongest antimicrobial activity was observed in Klebsilla pneumonia (MIC50 1.914 µg/mL), followed by E. coli (MIC50 1.923 µg/mL), Shigella (MIC50 1.813 µg/mL) and Salmonella typhi (MIC50 1.617 µg/mL). Bee bread samples possess antioxidant and antimicrobial properties. Bee bread contains phenolic acids and flavonoids, and could be beneficial in the management and treatment of metabolic diseases.
  12. Synthesis of Novel Esters of Mefenamic Acid with Pronounced Anti-nociceptive Effects and a Proposed Activity on GABA, Opioid and Glutamate Receptors
    Ayoub R, Jarrar Q, Ali D, Moshawih S, Jarrar Y, Hakim M, et al.
    Eur J Pharm Sci, 2021 Aug 01;163:105865.
    PMID: 33979659 DOI: 10.1016/j.ejps.2021.105865
    BACKGROUND: Mefenamic acid (MFA), a commonly prescribed non-steroidal anti-inflammatory drug (NSAID), possesses a greater risk of dose-related central nervous system (CNS) toxicity than other NSAIDs. In this study, α-tocopherol and α-tocopherol acetate were selected as prodrug moieties for MFA in an attempt to reduce the CNS toxicity and enhance the therapeutic efficacy.

    METHOD: α-tocopherol monoester of MFA (TMMA) and α-tocopherol di-ester of MFA (TDMA) were synthesized by esterification reaction and were subjected to various in vivo characterizations.

    RESULTS: Masking of the carboxylate group of MFA with the proposed pro-moieties significantly (p<0.05) delayed the onset of tonic-clonic seizure in mice. Besides, the intraperitoneal administration of TMMA and TDMA in mice produced significantly (p<0.05) stronger anti-inflammatory effects in the carrageenan-induced paw edema test and greater anti-nociceptive effect in the acetic acid-induced writhing test than MFA at an equimolar dose of 20 mg/kg. Treatment with TMMA and TDMA caused a significant (p<0.05) inhibition of pain at 1st and 2nd phases of formalin-induced licking test in mice, whereas treatment with MFA inhibited the 2nd phase only. Pretreatment with naloxone and flumazenil significantly (p<0.05) reversed the anti-nociceptive effect of MFA, TMMA and TDMA in the acetic acid-induced writhing test. In addition, treatment with TMMA and TDMA caused significantly (p<0.05) a higher inhibition of pain in the glutamate-induced licking response in mice than MFA.

    CONCLUSION: Masking the carboxylate moiety of MFA by α-tocopherol and α-tocopherol acetate has a great potential for reducing CNS toxicity, enhancing the therapeutic efficacy and altering the mode of anti-nociceptive action.

  13. Fulltext Cerebral venous sinus thrombosis 2 weeks after the first dose of mRNA SARS-CoV-2 vaccine
    Zakaria Z, Sapiai NA, Ghani ARI
    Acta Neurochir (Wien), 2021 08;163(8):2359-2362.
    PMID: 34101024 DOI: 10.1007/s00701-021-04860-w
    The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as coronavirus disease 2019 (COVID-19) is a highly transmissible virus and has become pandemic. Part of the prevention of disease spread by the Malaysian government is by getting COVID-19 vaccine. Using the mRNA technology, the Pfizer/BioNTech vaccine is one of the vaccines been approved by the Drug Control Authority in Malaysia. Herein, we report an immediate complication of cerebral VST after the first dose of the Pfizer/BioNTech vaccine.
  14. Fulltext Limitation of nutrients stimulates musty odor production by Streptomyces sp. isolated from a tropical environment
    Shudirman S, Abang Kassim A, Shamsol Anuar NS, Utsumi M, Shimizu K, Muhammad Yuzir MA, et al.
    J Gen Appl Microbiol, 2021 Jul 31;67(3):92-99.
    PMID: 33642451 DOI: 10.2323/jgam.2020.08.001
    Musty odor production by actinomycetes is usually related to the presence of geosmin and 2-methylisoborneol (2-MIB), which are synthesized by enzymes encoded by the geoA and tpc genes, respectively. Streptomyces spp. strain S10, which was isolated from a water reservoir in Malaysia, has the ability to produce geosmin when cultivated in a basal salt (BS) solid medium, but no 2-MIB production occurred during growth in BS medium. Strain S10 could produce higher levels of geosmin when the phosphate concentration was limited to 0.05 mg/L, with a yield of 17.53 ± 3.12 ✕ 105 ng/L, compared with growth in BS medium. Interestingly, 2-MIB production was suddenly detected when the nitrate concentration was limited to 1.0 mg/L, with a yield of 1.4 ± 0.11 ✕ 105 ng/L. Therefore, it was concluded that phosphate- and nitrate-limiting conditions could induce the initial production of geosmin and 2-MIB by strain S10. Furthermore, a positive amplicon of geoA was detected in strain S10, but no tpc amplicon was detected by PCR analysis. Draft genome sequence analysis showed that one open reading frame (ORF) contained a conserved motif of geosmin synthase with 95% identity with geoA in Streptomyces coelicolor A3 (2). In the case of the tpc genes, it was found that one ORF showed 23% identity to the known tpc gene in S. coelicolor A3(2), but strain S10 lacked one motif in the N-terminus.
  15. Fulltext Pharmacoinformatics and UPLC-QTOF/ESI-MS-Based Phytochemical Screening of Combretum indicum against Oxidative Stress and Alloxan-Induced Diabetes in Long-Evans Rats
    Forid MS, Rahman MA, Aluwi MFFM, Uddin MN, Roy TG, Mohanta MC, et al.
    Molecules, 2021 Jul 30;26(15).
    PMID: 34361788 DOI: 10.3390/molecules26154634
    This research investigated a UPLC-QTOF/ESI-MS-based phytochemical profiling of Combretum indicum leaf extract (CILEx), and explored its in vitro antioxidant and in vivo antidiabetic effects in a Long-Evans rat model. After a one-week intervention, the animals' blood glucose, lipid profile, and pancreatic architectures were evaluated. UPLC-QTOF/ESI-MS fragmentation of CILEx and its eight docking-guided compounds were further dissected to evaluate their roles using bioinformatics-based network pharmacological tools. Results showed a very promising antioxidative effect of CILEx. Both doses of CILEx were found to significantly (p < 0.05) reduce blood glucose, low-density lipoprotein (LDL), and total cholesterol (TC), and increase high-density lipoprotein (HDL). Pancreatic tissue architectures were much improved compared to the diabetic control group. A computational approach revealed that schizonepetoside E, melianol, leucodelphinidin, and arbutin were highly suitable for further therapeutic assessment. Arbutin, in a Gene Ontology and PPI network study, evolved as the most prospective constituent for 203 target proteins of 48 KEGG pathways regulating immune modulation and insulin secretion to control diabetes. The fragmentation mechanisms of the compounds are consistent with the obtained effects for CILEx. Results show that the natural compounds from CILEx could exert potential antidiabetic effects through in vivo and computational study.
  16. Biliary ascariasis - A vicious cycle
    Che Husin N, Mohamad IS, Ho KY, Soh JY, Syed Aziz SH, Zakaria Z
    Malays Fam Physician, 2021 Jul 22;16(2):83-85.
    PMID: 34386170 DOI: 10.51866/cr1078
    Biliary ascariasis is a rare disease in a non-endemic area. However, it is one of the possible etiological factors for retarded growth as well as malnutrition in children. It may cause intestinal obstruction, appendicitis, biliary obstruction, liver abscess, hepatolithiasis, and pancreatitis in adults. Herein, we report a patient with ascending cholangitis secondary to biliary ascariasis who was successfully managed with Endoscopic Retrograde Cholangio Pancreaticography.
  17. Fulltext Enhancement of astaxanthin accumulation using black light in Coelastrum and Monoraphidium isolated from Malaysia
    Kaha M, Iwamoto K, Yahya NA, Suhaimi N, Sugiura N, Hara H, et al.
    Sci Rep, 2021 06 03;11(1):11708.
    PMID: 34083633 DOI: 10.1038/s41598-021-91128-z
    Microalgae are important microorganisms which produce potentially valuable compounds. Astaxanthin, a group of xanthophyll carotenoids, is one of the most powerful antioxidants mainly found in microalgae, yeasts, and crustaceans. Environmental stresses such as intense light, drought, high salinity, nutrient depletion, and high temperature can induce the accumulation of astaxanthin. Thus, this research aims to investigate the effect of black light, also known as long-wave ultraviolet radiation or UV-A, as a stressor on the accumulation of astaxanthin as well as to screen the antioxidant property in two tropical green algal strains isolated from Malaysia, Coelastrum sp. and Monoraphidium sp. SP03. Monoraphidium sp. SP03 showed a higher growth rate (0.66 day-1) compared to that of Coelastrum sp. (0.22 day-1). Coelastrum sp. showed significantly higher accumulation of astaxanthin in black light (0.999 g mL culture-1) compared to that in control condition (0.185 g mL-1). Similarly, Monoraphidium sp. SP03 showed higher astaxanthin content in black light (0.476 g mL culture-1) compared to that in control condition (0.363 g mL culture-1). Coelastrum sp. showed higher scavenging activity (30.19%) when cultured in black light condition, indicating a correlation between the antioxidant activity and accumulation of astaxanthin. In this study, black light was shown to possess great potential to enhance the production of astaxanthin in microalgae.
  18. Fluid-structure interaction (FSI) modeling of bone marrow through trabecular bone structure under compression
    Rabiatul AAR, Fatihhi SJ, Md Saad AP, Zakaria Z, Harun MN, Kadir MRA, et al.
    Biomech Model Mechanobiol, 2021 Jun;20(3):957-968.
    PMID: 33547975 DOI: 10.1007/s10237-021-01423-x
    The present study has sought to investigate the fluid characteristic and mechanical properties of trabecular bone using fluid-structure interaction (FSI) approach under different trabecular bone orientations. This method imposed on trabecular bone structure at both longitudinal and transverse orientations to identify effects on shear stress, permeability, stiffness and stress regarded to the trabeculae. Sixteen FSI models were performed on different range trabecular cubes of 27 mm3 with eight models developed for each longitudinal and transverse direction. Results show that there was a moderate correlation between permeability and porosity, and surface area in the longitudinal and transverse orientations. For the longitudinal orientation, the permeability values varied between 3.66 × 10-8 and 1.9 × 10-7 and the sheer stress values varied between 0.05 and 1.8 Pa, whilst for the transverse orientation, the permeability values varied between 5.95 × 10-10 and 1.78 × 10-8 and the shear stress values varied between 0.04 and 3.1 Pa. Here, transverse orientation limits the fluid flow from passing through the trabeculae due to high shear stress disturbance generated within the trabecular bone region. Compared to physiological loading direction (longitudinal orientation), permeability is higher within the range known to trigger a response in bone cells. Additionally, shear stresses also increase with bone surface area. This study suggests the shear stress within bone marrow in real trabecular architecture could provide the mechanical signal to marrow cells that leads to bone anabolism and can depend on trabecular orientation.
  19. Fulltext Understanding Potential Heavy Metal Contamination, Absorption, Translocation and Accumulation in Rice and Human Health Risks
    Zakaria Z, Zulkafflee NS, Mohd Redzuan NA, Selamat J, Ismail MR, Praveena SM, et al.
    Plants (Basel), 2021 May 26;10(6).
    PMID: 34073642 DOI: 10.3390/plants10061070
    Rice is a worldwide staple food and heavy metal contamination is often reported in rice production. Heavy metal can originate from natural sources or be present through anthropogenic contamination. Therefore, this review summarizes the current status of heavy metal contamination in paddy soil and plants, highlighting the mechanism of uptake, bioaccumulation, and health risk assessment. A scoping search employing Google Scholar, Science Direct, Research Gate, Scopus, and Wiley Online was carried out to build up the review using the following keywords: heavy metals, absorption, translocation, accumulation, uptake, biotransformation, rice, and human risk with no restrictions being placed on the year of study. Cadmium (Cd), arsenic (As), and lead (Pb) have been identified as the most prevalent metals in rice cultivation. Mining and irrigation activities are primary sources, but chemical fertilizer and pesticide usage also contribute to heavy metal contamination of paddy soil worldwide. Further to their adverse effect on the paddy ecosystem by reducing the soil fertility and grain yield, heavy metal contamination represents a risk to human health. An in-depth discussion is further offered on health risk assessments by quantitative measurement to identify potential risk towards heavy metal exposure via rice consumption, which consisted of in vitro digestion models through a vital ingestion portion of rice.
  20. Fulltext Draft Genome Sequences of Three Multidrug-Resistant Staphylococcus spp. Isolated from Hospital Wastewater in Malaysia
    Ahmad Sabri NS, Mohd Zulkeflle SN, Yusof N, Md Akhir FN, Othman N, Zakaria Z, et al.
    Microbiol Resour Announc, 2021 May 06;10(18).
    PMID: 33958405 DOI: 10.1128/MRA.00332-21
    Staphylococcus spp. are Gram-positive bacteria that reside within the normal microbiota of humans and animals but pose a health threat as reservoirs of antimicrobial resistance genes. Here, we present the draft genome sequences of three Staphylococcus sp. strains isolated from hospital wastewater in Malaysia that demonstrated resistance to multiple antibiotics.
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