MyMedR

Displaying all 11 publications

Abstract:

Sort:

Determination of optimum harvest maturity and physico-chemical quality of Rastali banana (Musa AAB Rastali) during fruit ripening

Kheng TY, Ding P, Abdul Rahman NA

J Sci Food Agric, 2012 Jan 15;92(1):171-6.
PMID: 21780132 DOI: 10.1002/jsfa.4559

A series of physico-chemical quality (peel and pulp colours, pulp firmness, fruit pH, sugars and acids content, respiration rate and ethylene production) were conducted to study the optimum harvest periods (either week 11 or week 12 after emergence of the first hand) of Rastali banana (Musa AAB Rastali) based on the fruit quality during ripening.
Fulltext Adult female with acute renal failure and weight loss

Abdul-Rahman NA, Azman RR, Kumar G

Saudi Med J, 2016 May;37(5):584-6.
PMID: 27146625 DOI: 10.15537/smj.2016.5.15042
Fulltext Effects of glucose, ethanol and acetic acid on regulation of ADH2 gene from Lachancea fermentati

Yaacob N, Mohamad Ali MS, Salleh AB, Abdul Rahman NA

PeerJ, 2016;4:e1751.
PMID: 26989608 DOI: 10.7717/peerj.1751

Background. Not all yeast alcohol dehydrogenase 2 (ADH2) are repressed by glucose, as reported in Saccharomyces cerevisiae. Pichia stipitis ADH2 is regulated by oxygen instead of glucose, whereas Kluyveromyces marxianus ADH2 is regulated by neither glucose nor ethanol. For this reason, ADH2 regulation of yeasts may be species dependent, leading to a different type of expression and fermentation efficiency. Lachancea fermentati is a highly efficient ethanol producer, fast-growing cells and adapted to fermentation-related stresses such as ethanol and organic acid, but the metabolic information regarding the regulation of glucose and ethanol production is still lacking. Methods. Our investigation started with the stimulation of ADH2 activity from S. cerevisiae and L. fermentati by glucose and ethanol induction in a glucose-repressed medium. The study also embarked on the retrospective analysis of ADH2 genomic and protein level through direct sequencing and sites identification. Based on the sequence generated, we demonstrated ADH2 gene expression highlighting the conserved NAD(P)-binding domain in the context of glucose fermentation and ethanol production. Results. An increase of ADH2 activity was observed in starved L. fermentati (LfeADH2) and S. cerevisiae (SceADH2) in response to 2% (w/v) glucose induction. These suggest that in the presence of glucose, ADH2 activity was activated instead of being repressed. An induction of 0.5% (v/v) ethanol also increased LfeADH2 activity, promoting ethanol resistance, whereas accumulating acetic acid at a later stage of fermentation stimulated ADH2 activity and enhanced glucose consumption rates. The lack in upper stream activating sequence (UAS) and TATA elements hindered the possibility of Adr1 binding to LfeADH2. Transcription factors such as SP1 and RAP1 observed in LfeADH2 sequence have been implicated in the regulation of many genes including ADH2. In glucose fermentation, L. fermentati exhibited a bell-shaped ADH2 expression, showing the highest expression when glucose was depleted and ethanol-acetic acid was increased. Meanwhile, S. cerevisiae showed a constitutive ADH2 expression throughout the fermentation process. Discussion. ADH2 expression in L. fermentati may be subjected to changes in the presence of non-fermentative carbon source. The nucleotide sequence showed that ADH2 transcription could be influenced by other transcription genes of glycolysis oriented due to the lack of specific activation sites for Adr1. Our study suggests that if Adr1 is not capable of promoting LfeADH2 activation, the transcription can be controlled by Rap1 and Sp1 due to their inherent roles. Therefore in future, it is interesting to observe ADH2 gene being highly regulated by these potential transcription factors and functioned as a promoter for yeast under high volume of ethanol and organic acids.
Fulltext Microbial synthesis of zinc oxide nanoparticles and their potential application as an antimicrobial agent and a feed supplement in animal industry: a review

Mohd Yusof H, Mohamad R, Zaidan UH, Abdul Rahman NA

J Anim Sci Biotechnol, 2019;10:57.
PMID: 31321032 DOI: 10.1186/s40104-019-0368-z

In recent years, zinc oxide nanoparticles (ZnO NPs) have gained tremendous attention attributed to their unique properties. Notably, evidence has shown that zinc is an important nutrient in living organisms. As such, both prokaryotes and eukaryotes including bacteria, fungi and yeast are exploited for the synthesis of ZnO NPs by using microbial cells or enzyme, protein and other biomolecules compounds in either an intracellular or extracellular route. ZnO NPs exhibit antimicrobial properties, however, the properties of nanoparticles (NPs) are depended upon on their size and shape, which make them specific for various applications. Nevertheless, the desired size and shape of NPs can be obtained through the optimization process of microbes mediated synthesis by manipulating their reaction conditions. It should be noted that ZnO NPs are synthesized by various chemical and physical methods. Nonetheless, these methods are expensive and not environmentally friendly. On that account, the microbes mediated synthesis of ZnO NPs have rapidly evolved recently where the microbes are cleaner, eco-friendly, non-toxic and biocompatible as the alternatives to chemical and physical practices. Moreover, zinc in the form of NPs is more effective than their bulk counterparts and thus, they have been explored for many potential applications including in animals industry. Notably, with the advent of multi-drug resistant strains, ZnO NPs have emerged as the potential antimicrobial agents. This is mainly due to their superior properties in combating a broad spectrum of pathogens. Moreover, zinc is known as an essential trace element for most of the biological function in the animal's body. As such, the applications of ZnO NPs have been reported to significantly enhance the health and production of the farm animals. Thus, this paper reviews the biological synthesis of ZnO NPs by the microbes, the mechanisms of the biological synthesis, parameters for the optimization process and their potential application as an antimicrobial agent and feed supplement in the animal industry as well as their toxicological hazards on animals.
Post-traumatic hydrocephalus

Mohd Nor MA, Abdul Rahman NA, Adnan JS

Malays J Med Sci, 2013 Jan;20(1):95-6.
PMID: 23613662
Fulltext Seed biopriming with P- and K-solubilizing Enterobacter hormaechei sp. improves the early vegetative growth and the P and K uptake of okra (Abelmoschus esculentus) seedling

Roslan MAM, Zulkifli NN, Sobri ZM, Zuan ATK, Cheak SC, Abdul Rahman NA

PLoS One, 2020;15(7):e0232860.
PMID: 32645001 DOI: 10.1371/journal.pone.0232860

Limited information is available that seed biopriming with plant growth-promoting Enterobacter spp. play a prominent role to enhance vegetative growth of plants. Contrary to Enterobacter cloacae, Enterobacter hormaechei is a less-studied counterpart despite its vast potential in plant growth-promotion mainly through the inorganic phosphorus (P) and potassium (K) solubilization abilities. To this end, 18 locally isolated bacterial pure cultures were screened and three strains showed high P- and K-solubilizing capabilities. Light microscopy, biochemical tests and 16S rRNA gene sequencing revealed that strains 15a1 and 40a were closely related to Enterobacter hormaechei while strain 38 was closely related to Enterobacter cloacae (Accession number: MN294583; MN294585; MN294584). All Enterobacter spp. shared common plant growth-promoting traits, namely nitrogen (N2) fixation, indole-3-acetic acid production and siderophore production. The strains 38 and 40a were able to produce gibberellic acid, while only strain 38 was able to secrete exopolysaccharide on agar. Under in vitro germination assay of okra (Abelmoschus esculentus) seeds, Enterobacter spp. significantly improved overall germination parameters and vigor index (19.6%) of seedlings. The efficacy of root colonization of Enterobacter spp. on the pre-treated seedling root tips was confirmed using Scanning Electron Microscopy (SEM). The pot experiment of bioprimed seeds of okra seedling showed significant improvement of the plant growth (> 28%) which corresponded to the increase of P and K uptakes (> 89%) as compared to the uninoculated control plants. The leaf surface area and the SPAD chlorophyll index of bioprimed plants were increased by up to 29% and 9% respectively. This report revealed that the under-explored species of P- and K-solubilizing Enterobacter hormaechei sp. with multiple plant beneficial traits presents a great potential sustainable approach for enhancement of soil fertility and P and K uptakes of plants.
Fulltext The Molecular Approaches and Challenges of Streptococcus pneumoniae Serotyping for Epidemiological Surveillance in the Vaccine Era

Abdul Rahman NA, Mohd Desa MN, Masri SN, Taib NM, Sulaiman N, Hazman H, et al.

Pol J Microbiol, 2023 Jun 01;72(2):103-115.
PMID: 37314355 DOI: 10.33073/pjm-2023-023

Streptococcus pneumoniae (pneumococcus) belongs to the Gram-positive cocci. This bacterium typically colonizes the nasopharyngeal region of healthy individuals. It has a distinct polysaccharide capsule - a virulence factor allowing the bacteria to elude the immune defense mechanisms. Consequently, it might trigger aggressive conditions like septicemia and meningitis in immunocompromised or older individuals. Moreover, children below five years of age are at risk of morbidity and mortality. Studies have found 101 S. pneumoniae capsular serotypes, of which several correlate with clinical and carriage isolates with distinct disease aggressiveness. Introducing pneumococcal conjugate vaccines (PCV) targets the most common disease-associated serotypes. Nevertheless, vaccine selection pressure leads to replacing the formerly dominant vaccine serotypes (VTs) by non-vaccine types (NVTs). Therefore, serotyping must be conducted for epidemiological surveillance and vaccine assessment. Serotyping can be performed using numerous techniques, either by the conventional antisera-based (Quellung and latex agglutination) or molecular-based approaches (sequetyping, multiplex PCR, real-time PCR, and PCR-RFLP). A cost-effective and practical approach must be used to enhance serotyping accuracy to monitor the prevalence of VTs and NVTs. Therefore, dependable pneumococcal serotyping techniques are essential to precisely monitor virulent lineages, NVT emergence, and genetic associations of isolates. This review discusses the principles, associated benefits, and drawbacks of the respective available conventional and molecular approaches, and potentially the whole genome sequencing (WGS) to be directed for future exploration.
Fulltext Saccharification of rice straw by cellulase from a local Trichoderma harzianum SNRS3 for biobutanol production

Rahnama N, Foo HL, Abdul Rahman NA, Ariff A, Md Shah UK

BMC Biotechnol, 2014;14:103.
PMID: 25496491 DOI: 10.1186/s12896-014-0103-y

Rice straw has shown to be a promising agricultural by-product in the bioconversion of biomass to value-added products. Hydrolysis of cellulose, a main constituent of lignocellulosic biomass, is a requirement for fermentable sugar production and its subsequent bioconversion to biofuels such as biobutanol. The high cost of commercial enzymes is a major impediment to the industrial application of cellulases. Therefore, the use of local microbial enzymes has been suggested. Trichoderma harzianum strains are potential CMCase and β-glucosidase producers. However, few researches have been reported on cellulase production by T. harzianum and the subsequent use of the crude cellulase for cellulose enzymatic hydrolysis. For cellulose hydrolysis to be efficiently performed, the presence of the whole set of cellulase components including exoglucanase, endoglucanase, and β-glucosidase at a considerable concentration is required. Biomass recalcitrance is also a bottleneck in the bioconversion of agricultural residues to value-added products. An effective pretreatment could be of central significance in the bioconversion of biomass to biofuels.
A study on the magnitude and the effectiveness of the observation ward of hospital universiti sains malaysia

Ahmad R, Nik Abdul Rahman NH, Mohd Noh AY, Nik Abdul Rahman NA, Mohamad N, Baharudin KA

Malays J Med Sci, 2010 Jan;17(1):38-43.
PMID: 22135524 MyJurnal

BACKGROUND: The observation ward (OW) allows patients to be reassessed and monitored before deciding either to admit or to discharge them. This is a six-month descriptive cross-sectional study conducted in the observation ward of the Emergency Department (ED) of Hospital Universiti Sains Malaysia, Kelantan. The objective of this study was to examine the demographic characteristics and clinical profiles of adult observed patients and to determine the effectiveness of OW management.
METHODS: Patients were selected randomly by convenience sampling. One hundred and twenty-four patients were included in the study. The mean age was 40.3 ± 18.5 years (95% CI: 37.2 to 43.8).
RESULTS: Among the common clinical problems were abdominal discomfort (23%), diarrhoea and vomiting (13%) and fever (13%). Reasons for OW admission included diagnostic uncertainty (63%) and short course of treatment (33%). The mean length of stay was 4.1 ± 1.8 hours (95% CI=3.8 to 4.4 hours). Most of the patients (85%) were discharged.
CONCLUSIONS: The OW of HUSM is effective in managing adult patients as determined by the hospitalisation rate and the length of stay.
Fulltext Total pleurectomy as the surgical treatment for recurrent secondary spontaneous pneumothorax in a child with severe pulmonary Langerhans cells histiocytosis

Abdul Aziz DA, Abdul Rahman NA, Tang SF, Abdul Latif H, Zaki FM, Annuar ZM, et al.

BMJ Case Rep, 2011;2011.
PMID: 22674944 DOI: 10.1136/bcr.09.2011.4734

Pulmonary Langerhans cell histiocytosis (LCH) in children is more extensive and is a rare cause of spontaneous secondary pneumothorax (SSP) which tends to be recurrent and refractory to conventional treatment. Its occurrence in paediatric patients posed great challenge to the choice of surgical management. Surgery in the form of pleurodesis is only considered if SSP does not improve after chemotherapy and after considering all relevant risk and benefits of surgery to patients. Chemical pleurodesis will not give the expected effect to eradicate SSP in this patient. Therefore mechanical pleurodesis is the treatment of choice. There are various techniques to perform mechanical pleurodesis; from pleural abrasion to pleurectomy. In the authors' experience, bilateral total pleurectomy provided the best outcome for this 9-year-old patient with persistent respiratory distress from SSP due to extensive pulmonary LCH.
Fulltext Incorporation of Hydroxyapatite into Glass Ionomer Cement (GIC) Formulated Based on Alumino-Silicate-Fluoride Glass Ceramics from Waste Materials

Wan Jusoh WN, Matori KA, Mohd Zaid MH, Zainuddin N, Ahmad Khiri MZ, Abdul Rahman NA, et al.

Materials (Basel), 2021 Feb 18;14(4).
PMID: 33670465 DOI: 10.3390/ma14040954

Glass ionomer cement (GIC) is a well-known restorative material applied in dentistry. The present work aims to study the effect of hydroxyapatite (HA) addition into GIC based on physical, mechanical and structural properties. The utilization of waste materials namely clam shell (CS) and soda lime silica (SLS) glass as replacements for the respective CaO and SiO2 sources in the fabrication of alumino-silicate-fluoride (ASF) glass ceramics powder. GIC was formulated based on ASF glass ceramics, polyacrylic acid (PAA) and deionized water, while 1 wt.% of HA powder was added to enhance the properties of the cement samples. The cement samples were subjected to four different ageing times before being analyzed. In this study, the addition of HA caused an increment in density and compressive strength results along with ageing time. Besides, X-ray Diffraction (XRD) revealed the formation of fluorohydroxyapatite (FHA) phase in HA-added GIC samples and it was confirmed by Fourier Transform Infrared (FTIR) analysis which detected OH‒F vibration mode. In addition, needle-like and agglomeration of spherical shapes owned by apatite crystals were observed from Field Emission Scanning Electron Microscopy (FESEM). Based on Energy Dispersive X-ray (EDX) analysis, the detection of chemical elements in the cement samples were originated from chemical compounds used in the preparation of glass ceramics powder and also the polyacid utilized in initiating the reaction of GIC.