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Synthesis of cellulose nanofibers from jute fiber by using chemomechanical method

N SS, M N EE, C K K, M J N

F1000Res, 2024;13:40.
PMID: 39246826 DOI: 10.12688/f1000research.138665.1

BACKGROUND: Jute fiber is one of the most versatile natural fibers that is widely used as a raw material for packaging, textiles, and construction; and as a reinforcement in composite materials for heavy-duty applications. In the past, acid hydrolysis and mechanical treatment via the ball milling method were common in the extraction of cellulose nanofiber (CNFs) from natural plant fibers. However, there are some drawbacks of using those methods where there will be a huge quantity of acidic wastewater generated when the acid hydrolysis method is performed.
METHOD: This study investigated the potential use of a combination of chemical and mechanical methods in the extraction of jute CNFs. Through this method, the jute fibers were first chemically treated using sodium hydroxide (NaOH), sodium chlorite (NaClO 2) and sulphuric acid (H 2SO 4) to remove the non-cellulosic elements followed by mechanical milling by using a planetary ball mill.
RESULTS: The shape and size of the obtained CNFs were observed under a field emission scanning electron microscope (FESEM). This study revealed that jute CNFs were successfully extracted through the combination of chemical and mechanical treatment methods where the obtained CNFs reveal themselves in smooth fibrous morphology with a diameter of 23 nm and 150-200nm in length.
CONCLUSIONS: Jute cellulose nanofibers were successfully drawn out from raw jute fibers by means of a combination of chemical and mechanical treatment. The results obtained confirmed that the chemomechanical method is an effective technique for isolating the CNFs and its potential use as reinforcement material was explained.
Fulltext Prevalence of toenail onychomycosis among diabetics at a primary care facility in Malaysia

Muthupalaniappen L, Azimah MN, Kharuddin NF, Tzar MN

Southeast Asian J Trop Med Public Health, 2013 May;44(3):479-83.
PMID: 24050080

Onychomycosis increases the risk of developing secondary bacterial infection and cellulitis if left untreated. The aim of this study was to determine the prevalence of onychomycosis among diabetics and its associated factors. A cross sectional study using universal sampling of all type 1 and 2 diabetic patients attending a primary care facility of the Universiti Kebangsaan Malaysia (UKM) from January to March 2011 was conducted. Samples were taken from clinically abnormal nails and from the first right toenail in the absence of nail abnormalities and cultured for fungal elements. A total of 151 diabetics participated in the study. The mean patient age was 60.7 +/- 9.1 years. A total of 123 nail samples (81.5%) were culture positive for fungal elements. A positive correlation was found between onychomycosis and increasing age (p = 0.011) and clinically abnormal nails (p < 0.05). There were no significant correlations with gender, ethnic group, duration of diabetes, types of diabetes or glycemic control. The prevalence of onychomycosis among diabetics in our study was high.
Fulltext Prevalence of overweight and obese school children aged between 7 to 16 years amongst the major 3 ethnic groups in Kuala Lumpur, Malaysia

Kasmini K, Idris MN, Fatimah A, Hanafiah S, Iran H, Asmah Bee MN

Asia Pac J Clin Nutr, 1997 Sep;6(3):172-4.
PMID: 24394759

6239 children aged 7 to 16 years, attending 22 primary and secondary schools in Kuala Lumpur, Malaysia, were screened using a self report questionnaire, with their heights and weights measured using a digital electronic SECA beam balance. The selection was done by a two staged stratified random sampling from a total of 226 schools in Kuala Lumpur. The racial distribution was 56.7% Malays, 33.8% Chinese and 8.1% Indians; 3.6% (n:222) of the children were identified as obese and 6% (n:373) identified as overweight. The definitions of obese and overweight were computed using growth charts of the National Centre for Health Statistics (NCHS) from the median of the reference population. There were no significant differences amongst the 3 major ethnic groups in the obese group. The differences were significant in the overweight group with the Indians most overweight, followed by the Chinese and the Malays.
Fulltext Antigen expression pattern of acute promyelocytic leukaemia cases in Malaysia

Ambayya A, Zainina S, Salmiah MS, Sabariah MN

Med J Malaysia, 2014 Apr;69(2):64-9.
PMID: 25241814 MyJurnal

INTRODUCTION: Acute Promyelocytic Leukaemia (APL) is associated with devastating coagulopathy and life threatening condition which requires immediate medical attention. It is crucial to establish an expedited diagnosis as early therapeutic intervention has led to optimal patient management. In this study, we assessed the type and frequency of antigen expressions in APL and correlated these findings with genetic studies.

METHODS: Multiparametric immunophenotyping was performed on 30 samples and findings were correlated with karyotypes, FISH for t(15;17) translocation and RT-PCR for PML-RARΑ for detection of breakpoint cluster regions (bcr1,bcr2 and bcr3).

RESULTS: On SSC/CD45, APL cells displayed high to moderate SSC, with the expression of CD33 (100%), CD13 (96.8%), cMPO (71%) but lacked CD34 (3.2%) and HLA-DR (9.7%). Aberrant expression of CD4 was seen in 12.9% and CD56 in 6.5% of the cases. A significant association between cumulative aberrant antigen expression and bcr1 were observed bcr1 (X2(2) =6.833,p.05) and (X2(2)=4.599,p>.05) respectively.

CONCLUSIONS: Flow cytometry is a rapid and effective tool in detecting APL. It is interesting to note that there is significant association between cumulative aberrant antigen expression and genotype analysis. Further validation is required to corroborate this relationship.
Fulltext Design of a compact tuning fork-shaped notched ultrawideband antenna for wireless communication application

Shakib MN, Moghavvemi M, Mahadi WN

ScientificWorldJournal, 2014;2014:874241.
PMID: 24723835 DOI: 10.1155/2014/874241

A new compact planar notched ultrawideband (UWB) antenna is designed for wireless communication application. The proposed antenna has a compact size of 0.182λ × 0.228λ × 0.018λ where λ is the wavelength of the lowest operating frequency. The antenna is comprised of rectangular radiating patch, ground plane, and an arc-shaped strip in between radiating patch and feed line. By introducing a new Tuning Fork-shaped notch in the radiating plane, a stopband is obtained. The antenna is tested and measured. The measured result indicated that fabricated antenna has achieved a wide bandwidth of 4.33-13.8 GHz (at -10 dB return loss) with a rejection frequency band of 5.28-6.97 GHz (WiMAX, WLAN, and C-band). The effects of the parameters of the antenna are discussed. The experiment results demonstrate that the proposed antenna can well meet the requirement for the UWB communication in spite of its compactness and small size.
Isolation of microsatellites in the bighead catfish, Clarias macrocephalus and cross-amplification in selected Clarias species

Nazia AK, Siti Azizah MN

Mol Biol Rep, 2014 Mar;41(3):1207-13.
PMID: 24381108 DOI: 10.1007/s11033-013-2965-9

The present study documents the isolation of eight polymorphic microsatellite markers from the bighead catfish, Clarias macrocephalus and cross-amplification in two other catfish species. The number of alleles per locus in C. macrocephalus ranged from 2 to 21. The most polymorphic locus was NCm-G12 with 21 alleles while the least polymorphic locus was NCm-H2 with only two alleles. Locus NCm-F8 significantly deviated from Hardy-Weinberg equilibrium (P value <0.05) after Bonferroni correction. Linkage disequilibrium was non-significant in all loci comparisons. The observed and expected heterozygosities varied from 0.033 to 0.967 and from 0.033 to 0.942, respectively. Mean polymorphic information content for the eight loci was 0.765. Cross-amplification was successfully performed with two other catfish species, C. batrachus and C. meladerma for all eight loci. Locus NCm-D8 was monomorphic in both species while NCm-F8 was monomorphic only in C. batrachus. These newly developed markers would be useful for better management and conservation of the economically important C. macrocephalus species.
Fulltext Ochrobactrum anthropi catheter-related bloodstream infection: the first case report in malaysia

Siti Rohani AH, Tzar MN

Med J Malaysia, 2013 Jun;68(3):267-8.
PMID: 23749021 MyJurnal

A 60-year old Malay man presented with an intermittent lowgrade fever for 3 days and worsening of right ankle ulcers. He was known to have ischaemic heart disease, diabetes mellitus type 2, hypertension and end stage renal failure and was on regular haemodialysis. The organisms isolated from the peripheral and central blood specimens were identified as Ochrobactrum anthropi, a rarely encountered gramnegative bacillus with a unique antibiotic susceptibility profile. His condition improved after removal of the catheters and administration of antibiotic therapy. This case report highlights the importance of being wary of such rare, opportunistic pathogens and good communication between the microbiologists and the clinicians.
High cell density fed-batch fermentations for lipase production: feeding strategies and oxygen transfer

Salehmin MN, Annuar MS, Chisti Y

Bioprocess Biosyst Eng, 2013 Nov;36(11):1527-43.
PMID: 23539203 DOI: 10.1007/s00449-013-0943-1

This review is focused on the production of microbial lipases by high cell density fermentation. Lipases are among the most widely used of the enzyme catalysts. Although lipases are produced by animals and plants, industrial lipases are sourced almost exclusively from microorganisms. Many of the commercial lipases are produced using recombinant species. Microbial lipases are mostly produced by batch and fed-batch fermentation. Lipases are generally secreted by the cell into the extracellular environment. Thus, a crude preparation of lipases can be obtained by removing the microbial cells from the fermentation broth. This crude cell-free broth may be further concentrated and used as is, or lipases may be purified from it to various levels. For many large volume applications, lipases must be produced at extremely low cost. High cell density fermentation is a promising method for low-cost production: it allows a high concentration of the biomass and the enzyme to be attained rapidly and this eases the downstream recovery of the enzyme. High density fermentation enhances enzyme productivity compared with the traditional submerged culture batch fermentation. In production of enzymes, a high cell density is generally achieved through fed-batch operation, not through perfusion culture which is cumbersome. The feeding strategies used in fed-batch fermentations for producing lipases and the implications of these strategies are discussed. Most lipase-producing microbial fermentations require oxygen. Oxygen transfer in such fermentations is discussed.
Fulltext Characterization and safety assessment of bioengineered limbal epithelium

Lim MN, Umapathy T, Baharuddin PJ, Zubaidah Z

Med J Malaysia, 2011 Oct;66(4):335-41.
PMID: 22299553 MyJurnal

Transplantation of cultivated limbal epithelium on substrates such as amniotic membrane is an established treatment for severe ocular surface disease with limbal stem cell deficiency. In this study, we adapted an established method to generate sheets of limbal epithelium on amniotic membrane and characterized the cells contained in these sheets and tested them for safety with regard to microbial contamination. Human limbal biopsies were cultivated on denuded amniotic membranes. After three weeks of culture, the phenotypes of cultivated cells were analyzed by immunohistochemistry and real-time RT-PCR for the expression of a panel of specific markers. Cultivated limbal epithelial cell sheets were also analyzed by scanning (SEM) and transmission (TEM) electron microscopy. Sterility tests and mycoplasma assays were conducted for the safety of product. A confluent layer of polygonal cells was formed in 2 weeks and 1-3 stratified layer of cells were observed after three weeks of culture. Cultivated cells were positive for p63, K3, K19, and involucrin but negative for K14, integrin alpha9 and ABCG2 when analyzed by immunohistochemistry. Expression of molecular markers was detectable with real-time RT-PCR. SEM showed multilayer of flat squamous polygonal epithelial cells. Desmosomal and hemidesmosomal attachments were evident. Our study showed that cultivated limbal epithelium consists of limbal progenitors as well as differentiated corneal epithelial cells. SEM and TEM analysis showed cultivated cells demonstrated typical features of corneal epithelium. The risk of contamination is low and can be prevented by culturing the cells in a clean room facility complying to Good Manufacturing Practice standard.
Desiccation sensitivity and cryopreservation of excised embryonic axes of Citrus suhuiensis cv. limau madu, Citrumelo [Citrus paradisi macf. × Poncirus trifoliata (l.) raf.] and Fortunella polyandra

Al Zoubi OM, Normah MN

Cryo Letters, 2012 May-Jun;33(3):241-51.
PMID: 22825791

Excised embryonic axes from seeds of three taxa, namely, Citrus suhuiensis cv. limau madu, Citrumelo (Citrus paradisi x Poncirus trifoliate) and Fortunella polyandra, were desiccated in a laminar airflow, over silica gel, and ultra-rapidly. Desiccation sensitivity (WC50) was estimated for each taxon using the quantal response model. High desiccation tolerance (WC50 = 0.11 g water per g dry mass. g/gdw) was observed for limau madu embryonic axes desiccated in a laminar airflow and ultra-rapidly (WC50 =0.10 g/gdw). Desiccation tolerance was substantially lower (WC50 = 0.19 g/gdw) for silica gel dehydration. Similarly, high desiccation tolerance (WC50 = 0.15 g/gdw) was associated with F. polyandra embryonic axes when desiccated in a laminar airflow, while a lower desiccation tolerance (WC50 = 0.17 g/gdw) was observed with silica gel dehydration. Ultra-rapid desiccation led to the highest desiccation tolerance (WC50 = 0.14 g/gdw). The dehydration rate, however, had no influence on desiccation tolerance (WC50 ~ 0.14 g/gdw) for Citrumelo embryonic axes. After each desiccation period, embryonic axes were directly immersed in liquid nitrogen (LN) followed by rapid rewarming. Normal seedling recovery of 80 to 83% for excised embryonic axes of limau madu was observed for laminar airflow and ultra-rapid dehydration, but for silica gel dehydration, 57% recovery was obtained. Similarly, for Citrumelo, high recoveries of 100% and 97% were obtained from axes desiccated in a laminar airflow and using ultra-rapid dehydration, respectively, whereas a lower value was associated with silica gel dehydration (80%). For F. polyandra, 50% recovery was obtained both for laminar airflow and ultra-rapid dehydration, while much lower recovery (43%) was associated with silica gel dehydration. Regardless of the drying method employed, axis survival percentages following exposure to LN were commensurate with the desiccation sensitivity pattern.
Fulltext Cardiac mass in a patient with sigmoid adenocarcinoma: a metastasis?

Ngow HA, Khairina WM

Cardiovasc J Afr, 2012 Aug;23(7):e10-2.
PMID: 22915057 DOI: 10.5830/CVJA-2012-027

Cardiac metastasis from a bowel malignancy seldom occurs and there is a limited number of case reports published on this subject. Although colorectal cancer is the third commonest malignancy in Malaysia, the incidence of cardiac metastasis has never been reported. We report a case of an elderly man with recently diagnosed adenocarcinoma of the sigmoid colon, who presented with congestive cardiac failure secondary to mechanical obstruction by a right atrial mass. The intractable shock led to his sudden death before any intervention could be planned. If an intra-cavity cardiac mass is detected in a patient with an underlying metastatic malignancy, cardiac metastasis should be suspected. However, primary cardiac tumour or thrombus could also be the differential diagnosis. In our case, the definitive cardiac pathology remained unsolved as an autopsy was refused.
Computational intelligent gait-phase detection system to identify pathological gait

Senanayake CM, Senanayake SM

IEEE Trans Inf Technol Biomed, 2010 Sep;14(5):1173-9.
PMID: 20801745 DOI: 10.1109/TITB.2010.2058813

An intelligent gait-phase detection algorithm based on kinematic and kinetic parameters is presented in this paper. The gait parameters do not vary distinctly for each gait phase; therefore, it is complex to differentiate gait phases with respect to a threshold value. To overcome this intricacy, the concept of fuzzy logic was applied to detect gait phases with respect to fuzzy membership values. A real-time data-acquisition system was developed consisting of four force-sensitive resistors and two inertial sensors to obtain foot-pressure patterns and knee flexion/extension angle, respectively. The detected gait phases could be further analyzed to identify abnormality occurrences, and hence, is applicable to determine accurate timing for feedback. The large amount of data required for quality gait analysis necessitates the utilization of information technology to store, manage, and extract required information. Therefore, a software application was developed for real-time acquisition of sensor data, data processing, database management, and a user-friendly graphical-user interface as a tool to simplify the task of clinicians. The experiments carried out to validate the proposed system are presented along with the results analysis for normal and pathological walking patterns.
Non-invasive diagnosis of risk in dengue patients using bioelectrical impedance analysis and artificial neural network

Ibrahim F, Faisal T, Salim MI, Taib MN

Med Biol Eng Comput, 2010 Nov;48(11):1141-8.
PMID: 20683676 DOI: 10.1007/s11517-010-0669-z

This paper presents a new approach to diagnose and classify early risk in dengue patients using bioelectrical impedance analysis (BIA) and artificial neural network (ANN). A total of 223 healthy subjects and 207 hospitalized dengue patients were prospectively studied. The dengue risk severity criteria was determined and grouped based on three blood investigations, namely, platelet (PLT) count (less than or equal to 30,000 cells per mm(3)), hematocrit (HCT) (increase by more than or equal to 20%), and either aspartate aminotransferase (AST) level (raised by fivefold the normal upper limit) or alanine aminotransferase (ALT) level (raised by fivefold the normal upper limit). The dengue patients were classified according to their risk groups and the corresponding BIA parameters were subsequently obtained and quantified. Four parameters were used for training and testing the ANN which are day of fever, reactance, gender, and risk group's quantification. Day of fever was defined as the day of fever subsided, i.e., when the body temperature fell below 37.5°C. The blood investigation and the BIA data were taken for 5 days. The ANN was trained via the steepest descent back propagation with momentum algorithm using the log-sigmoid transfer function while the sum-squared error was used as the network's performance indicator. The best ANN architecture of 3-6-1 (3 inputs, 6 neurons in the hidden layer, and 1 output), learning rate of 0.1, momentum constant of 0.2, and iteration rate of 20,000 was pruned using a weight-eliminating method. Eliminating a weight of 0.05 enhances the dengue's prediction risk classification accuracy of 95.88% for high risk and 96.83% for low risk groups. As a result, the system is able to classify and diagnose the risk in the dengue patients with an overall prediction accuracy of 96.27%.
Effects of asiatic acid on passive and active avoidance task in male Spraque-Dawley rats

Nasir MN, Habsah M, Zamzuri I, Rammes G, Hasnan J, Abdullah J

J Ethnopharmacol, 2011 Mar 24;134(2):203-9.
PMID: 21167268 DOI: 10.1016/j.jep.2010.12.010

Centella asiatica has a reputation to restore declining cognitive function in traditional medicine. To date, only a few compounds that show enhancing learning and memory properties are available. Therefore, the present study investigates the effects of for acute administration of asiatic acid (A-A) isolated from Centella asiatica administration on memory and learning in male Spraque-Dawley rats.
Fulltext Spawning seasons of Rasbora tawarensis (Pisces: Cyprinidae) in Lake Laut Tawar, Aceh province, Indonesia

Muchlisin ZA, Musman M, Azizah MN

Reprod Biol Endocrinol, 2010;8:49.
PMID: 20482777 DOI: 10.1186/1477-7827-8-49

Rasbora tawarensis is an endemic freshwater fish in Lake Laut Tawar, Aceh Province, Indonesia. Unfortunately, its status is regarded as critical endangered with populations decreasing in recent years. To date no information on the spawning activities of the fish are available. Therefore, this study provides a contribution to the knowledge on reproductive biology of R. tawarensis especially on spawning seasons as well as basic information for conservation of the species.
Composition and thermal characteristics of Madhuca longifolia seed fat and its solid and liquid fractions

Marikkar JM, Ghazali HM, Long K

J Oleo Sci, 2010;59(1):7-14.
PMID: 20032594

This study was to characterize the seed fat from Madhuca longifolia known as Mee fat and its solid and liquid fractions with the objective of distinguishing them. A sample of Mee fat was partitioned into solid and liquid fractions using acetone as the solvent medium. The isolated fractions were compared to the native Mee fat sample with respect to various physico-chemical parameters using standard chemical methods as well as instrumental techniques such as, gas liquid chromatography (GLC), reversed-phase high performance liquid chromatography (RP-HPLC), and differential scanning calorimetry (DSC). Basic analyses indicated that there were wide variations between the native sample and its fractions with respect to iodine value (IV), and slip melting point (SMP). The cloud point (CP) of the liquid fraction was found to be 10.5 degrees C. Fatty acid compositional analyses showed that the proportion of saturated fatty acids (SFA) such as palmitic and stearic went up in the high-melting fraction (HMF) while in low-melting fraction (LMF) the proportion of unsaturated fatty acid (USFA) such as oleic and lenoleic increased. According to the HPLC analyses, Mee fat had a tiacyl glycerol (TAG) sequence similar to that of palm oil. After fractionation, the solid and liquid fractions obtained were found to have TAG profiles very much different from the native sample. Thermal analyses by DSC showed that Mee fat had two-widely separated high and low melting thermal transitions, a feature which was beneficial for the effective separation of solid and liquid fractions. The thermal profiles displayed by the fractions were clearly distinguishable from that of the native sample.
Fulltext Handlebar herniation: a case of near missed abdominal injury

Chew KS, Amin NM

Med J Malaysia, 2009 Jun;64(2):170-1.
PMID: 20058582 MyJurnal

Timely identification of specific injuries in a polytrauma case is of paramount importance in order to reduce morbidity and mortality. Unfortunately, some of these injuries are subtle and can be missed on initial primary and secondary assessments. In this paper, we report one such injury in a case of a 16-year old motorcyclist who complained of abdominal pain over the right lumbar region after the motorcycle handlebar hit his abdomen. Although initial assessment was uneventful, he was subsequently diagnosed to have a traumatic abdominal wall herniation on abdominal computed tomography after more than 24 hours of observation in the ward.
Fulltext Nodular fasciitis: a diagnostic dilemma

Mallina S, Rosalind S, Philip R, Harvinder S, Gurdeep S, Sabaria MN

Med J Malaysia, 2007 Dec;62(5):420-1.
PMID: 18705482 MyJurnal

A 65 year old man presented with a right upper cervical mass. A diagnosis of pleomorphic adenoma was reported on fine needle aspiration cytology (FNAC). CT scan however reported an intramuscular sternocleidomastoid swelling. The tumor was excised and a diagnosis of nodular fasciitis was made. It is important to be aware of this diagnosis and that FNAC reports may mimic that of a pleomorphic adenoma.
Fulltext The blood pressure variability, arterial elasticity and humoral factors in subjects with family history of hypertension

Rafidah HM, Azizi A, Suhaimi H, Noriah MN

Med J Malaysia, 2008 Mar;63(1):9-16.
PMID: 18935724 MyJurnal

Normotensive subjects with family history of hypertension (FHT) have been reported to have increased left ventricular mass index and reduced ventricular compliance. Of interest is whether blood pressure variability (BPV), which has been associated with target organ damage, is then part of this complex inherited syndrome? The objectives of this study are to determine whether there are any significant differences in BPV, arterial compliance and humoral factors in subjects with FHT as compared to controls. Thirty-five subjects with self reported FHT and 35 matched controls underwent 24 hour BP monitoring (BR-102, Schiller Inc. Germany). Arterial compliance was measured using systolic pulse wave tonometry (HDI/Pulsewave Cardiovascular Profiling Instrument, Hypertension Diagnostic Inc. USA). None of the subjects were hypertensive or diabetic. Out of these numbers, 25 subjects with FHT and 26 controls had measurements of plasma catecholamines, plasma renin and serum aldosterone. Catecholamines were assayed with high performance liquid chromatography, while both renin and aldosterone measurements were by radioimmunoassay. Subjects with FHT have higher night time BPV. There was no significant difference in arterial compliances between both groups. There were increased level of norepinephrine (NE) in subjects with FHT but epinephrine (E), renin and aldosterone levels were similar in both groups. There were no correlations between NE and BPV but E was negatively associated with daytime and mean arterial systolic BPV. In conclusion subjects with FHT demonstrated a higher night time BPV and NE level as compared to controls.
Fulltext Proptosis presenting as a delayed sign of frontal extradural haematoma

Saiful MN, Azmi A, Saffari MH

Med J Malaysia, 2007 Jun;62(2):156-7.
PMID: 18705451 MyJurnal

We report a case of a young man who presented with proptosis as a delayed manifestation of a frontal extradural haematoma (EDH) following a minor head injury. A computed tomography (CT) of the brain done 72 hours after trauma revealed a large extradural haematoma in the right anterior cranial fossa with orbital roof fracture and subperiosteal clot extension into the orbital cavity. Right frontal craniotomy with evacuation of haematoma was done and the proptosis completely resolved after surgery. The clinical course, possible mechanism and management of the patient are discussed.

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