MyMedR

Ultrastructural changes during asexual multiple reproduction in Trichomonas vaginalis

Yusof A, Kumar S

Parasitol Res, 2012 May;110(5):1823-8.

PMID: 22076052 DOI: 10.1007/s00436-011-2705-9

Trichomonas vaginalis, a flagellated protozoan parasite, is commonly found in the genitourinary tract of humans. Its mode of reproduction has always been reported to be binary fission. The high parasite numbers seen in a relatively short period in in vitro cultures led us to believe that there must be other modes of reproduction. The present study for the first time provides transformational evidence at the ultrastructural level seen in tropohozoites of T. vaginalis undergoing a multiple asexual mode of reproduction. The findings show that the single cell with a nucleus is capable of dividing to as many as eight nuclei within the cytoplasmic body. Before the commencement of division, the nucleus remained round or ovoid in shape with condensed chromatin masses and only a few endoplasmic reticula surrounding the nucleus. During the division, the nucleus started to elongate and become irregular in shape with visible chromatin masses condensing with the accumulation of numerous endoplasmic reticula. Nuclear division gave rise to as many as eight nuclei within a cell, which could be seen to be connected by numerous endoplasmic reticula. In addition, a high number of hydrogenosomes and vacuoles can be seen in multinucleated T. vaginalis compared with single nucleated T. vaginalis. This study confirms that multiple modes of nuclear division do exist in T. vaginalis and are a precursor to progeny formation.

Fulltext Fatigue index and fatigue rate during an anaerobic performance under hypohydrations

Naharudin MN, Yusof A

PLoS One, 2013;8(10):e77290.

PMID: 24204790 DOI: 10.1371/journal.pone.0077290

BACKGROUND: Since hypohydration commonly occurs in sports, studies on anaerobic exercise performance under this condition have been extensively carried out. When describing anaerobic performance, authors usually refer to a drop in anaerobic performance as fatigue index (FI) which is conventionally calculated using peak and low power data points. Meanwhile, another possible method in explaining anaerobic fatigue is using the rate constant which is derived from the exponential decline of power output known as fatigue rate (FR). Few studies have demonstrated that there was no change in anaerobic performance under mild hypohydrations.

PURPOSE: This study aimed to compare the kinetics of power output using FI and FR of an anaerobic performance (Wingate test) under 2, 3 and 4% state of hypohydrations.

METHOD: Thirty two collegiate cyclists (age = 22 ± 2 years; body weight = 71.45 ± 3.43 kg; height = 173.23 ± 0.04 cm) were matched using their baseline anaerobic peak power (APP) then randomly divided into 4 groups of EU (euhydrated), 2H, 3H and 4H respectively.

RESULTS: As expected the, FI, APP, anaerobic lower power (ALP) and rating of perceived exertion (RPE) did not show significant differences between and within the groups. However, the FR in 3H (0.018 ± 0.005 s(-1)) and 4H (0.019 ± 0.010 s(-1)) were significantly lower than EU (0.033 ± 0.012 s(-1)). Post-test FR also showed significant reduction in 3H and 4H compared to their pre-test values (p<0.05).

CONCLUSION: Despite the lack of changes in APP and RPE, subjects in 3H and 4H showed evidence of lower reduction of power output over time. The findings support earlier reports which showed no change in anaerobic performance under mild hypohydrations. The relatively lower FR suggests higher drive in maintaining power output under hypohydrations of 3 and 4% body weight.

The distribution of uranium and thorium in samples taken from different polluted marine environment

Akyil S, Yusof AM

J Hazard Mater, 2007 Jun 1;144(1-2):564-9.

PMID: 17141412

Concentrations of uranium and thorium in seawater, sediment and some marine species taken from along the coastal areas of Malaysia were determined spectrophotometrically. The uranium and thorium concentrations in seawater were found to vary ranging from 1.80 to 4.1 and 0.14 to 0.88 microg/L, respectively. The concentration of uranium in sediment samples was reported to range from 3.00 to 6.60 microg/g while those of thorium were slightly lower ranging from 0.01 to 0.68 microg/g. The uptake of uranium and thorium in marine species was found to be rather low. Similar variations in total alpha activities in samples were also observed with the total alpha activities relatively lower than the beta activities in most samples.

Fulltext Displaced supracondylar fracture of humerus in children--comparative study of the result of closed and open reduction

Yusof A, Razak M, Lim A

Med J Malaysia, 1998 Sep;53 Suppl A:52-8.

PMID: 10968183

The displaced supracondylar fracture of the humerus in children (Gartland type 3) is a most challenging injury to treat. There is controversy regarding the initial treatment either closed manipulation and splint immobilization or open reduction and internal fixation. This is a retrospective study comparing two groups of patients with displaced supracondylar fracture of the humerus (Gattland 3) treated in the Orthopaedic Unit, Universiti Kebangsaan Malaysia. The first group, 13 patients treated with closed reduction and splint immobilization and a second group, 15 patients treated with open reduction and internal fixation as initial definitive treatment. The results showed a high failure rate of closed reduction and splint immobilization. This was due to difficulty in reduction, loss of reduction post operatively or during follow-up. Open reduction and internal fixation was more advantages with reduced hospitalization time, fewer complications, more stable fixation and better anatomical reduction with minimal complications for type 3 supracondylar fracture of humerus. We would recommend that all Gartland 3 supracondylar fracture of the humerus be treated with open reduction and two K-wire fixation.

The effect of 10 days of energy-deficit diet and high-intensity exercise training on the plasma high-density-lipoprotein (HDL) level among healthy collegiate males

Naharudin MN, Yusof A

Eur J Sport Sci, 2021 Jan 18.

PMID: 33357008 DOI: 10.1080/17461391.2020.1869836

ABSTRACTAn energy-deficit (ED) diet increases lipid mobilisation, while endurance exercise improves lipid profile by promoting formation of high-density lipoproteins (HDLs) among moderately active population. However, it is not clear whether ED with high-intensity exercise training can improve lipid profiles. Therefore, 20 recreationally active males (20.3 ± 2.7 years old with peak oxygen consumption (

V

˙

O2peak) of 2.8 ± 0.2 L min-1) with HDL concentration of 1.44 ± 0.32 mmol L-1, were evenly allocated to either an ED group (1590 ± 79 kcal day-1: 40% of total caloric omitted at lunchtime) or a control (CON) group (2570 ± 139 kcal day-1). Participants in both groups performed high-intensity cycling at 90%

V

˙

O2peak at a constant workload for 8 min, 2 h after breakfast on day D0, D2, D4, D6, D8 and D10 (Dn is day number), after which blood samples were collected. In ED, compared to D0, triglycerides (TG) decreased on D6-10 (p

Fulltext Food waste handling in Malaysia and comparison with other Asian countries

Lim, W. J., Chin, N. L., Yusof, A. Y., Yahya, A., Tee, T. P.

International Food Research Journal, 2016;23(101):1-6.

MyJurnal

The increasing amount of food waste in Malaysia in recent years has brought many environmental
issues in the country where it affects the nation’s solid waste management framework. At the
moment, the government is limited to other alternatives of food waste disposal besides the
conventional landfill and incineration methods. This paper provides information on the current
status of food waste handling, management, regulations, and policies in Malaysia. It helps
to draw the problem and challenge to a clearer view in efforts of achieving sustainable and
integrative food waste handling in the country.

Fulltext The effects of injury prevention warm-up programmes on knee strength in male soccer players

Daneshjoo A, Mokhtar A, Rahnama N, Yusof A

Biol Sport, 2013 Dec;30(4):281-8.

PMID: 24795499 DOI: 10.5604/20831862.1077554

The study investigates the effects of the 11+ and HarmoKnee injury prevention programmes on knee strength in male soccer players. Under-21-year-old players (n=36) were divided equally into: the 11+, HarmoKnee and control groups. The programmes were performed for 24 sessions (20-25 min each). The hamstrings and quadriceps strength were measured bilaterally at 60°·s(-1), 180°·s(-1) and 300°·s(-1). The concentric quadriceps peak torque (PT) of the 11+ increased by 27.7% at 300°·s(-1) in the dominant leg (p<0.05). The concentric quadriceps PT of HarmoKnee increased by 36.6%, 36.2% and 28% in the dominant leg, and by 31.3%, 31.7% and 20.05% at 60°·s(-1), 180°·s(-1) and 300°·s(-1) in the non-dominant leg respectively. In the 11+ group the concentric hamstring PT increased by 22%, 21.4% and 22.1% at 60°·s(-1), 180°·s(-1) and 300°·s(-1), respectively in the dominant leg, and by 22.3%, and 15.7% at 60°·s(-1) and 180°·s(-1), in the non-dominant leg. In the HarmoKnee group the hamstrings in the dominant leg showed an increase in PT by 32.5%, 31.3% and 14.3% at 60°·s(-1), 180°·s(-1) and 300°·s(-1), and in the non-dominant leg hamstrings PT increased by 21.1% and 19.3% at 60°·s(-1) and 180°·s(-1) respectively. The concentric hamstrings strength was significantly different between the 11+ and control groups in the dominant (p=0.01) and non-dominant legs (p=0.02). The HarmoKnee programme enhanced the concentric strength of quadriceps. The 11+ and HarmoKnee programmes are useful warm-up protocols for improving concentric hamstring strength in young professional male soccer players. The 11+ programme is more advantageous for its greater concentric hamstring strength improvement compared to the HarmoKnee programme.

Fulltext Colonic and small bowel metastasis from ductal carcinoma of the breast : a case report

Visalini S, Daphne A, Mohamed Yusof AW

Med J Malaysia, 2013 Dec;68(6):477-8.

PMID: 24632919 MyJurnal

Pro-inflammatory properties of the kallikrein-kinin system: potential for new drug therapy

Sharma JN, Yusof AP

Inflammopharmacology, 1998;6(4):289-96.

PMID: 17657626

Components of the kallikrein-kinin system are activated in response to noxious stimuli (chemical, physical or bacterial), which may lead to excessive release of kinins in the synovial joints that may produce inflammatory joint disease. The inflammatory changes observed in synovial tissue may be due to activation of B(2) receptors. Kinins also stimulate the synthesis of other pro-inflammatory agents (PGs, LTs, histamine, EDRF, PGI(2) and PAF) in the inflamed joint. B(2)-receptor antagonists may provide valuable agents as new analgesic drugs. Furthermore, it is suggested that substances to reduce activation of the kallikrein-kinin system (KKS) may provide a pharmacological basis for the synthesis of novel antirheumatic or anti-inflammatory drugs.

Fulltext Orthopaedic infections: organisms and antibiotic sensitivity

Yusof MI, Yusof AH

Med J Malaysia, 2004 Dec;59(5):574-7.

PMID: 15889557

Staphylococcus aureus infection remains the commonest organism causing musculoskeletal infection and antibiotic is the mainstay of treatment apart from adequate and appropriate surgical intervention. The exact figure of antibiotic resistance in orthopaedic practice is not known but it is expected to be higher than previously reported as the use of antibiotics is rampant. Its sensitivity to various antibiotics differs from one center to another making local surveillance necessary. From 66 patients with musculoskeletal infections studied in our centre, Staphylococcus aureus was cultured in 50-65% of patients, depending on the sample taken. Fifteen percent of this were methicillin resistant Staphylococcus aureus (MRSA). Staphylococcus aureus was found to be sensitive to cloxacillin in 95% of patients' sample. MRSA remained highly sensitive to vancomycin, clindamycin and fucidic acid.

ANN modeling of the penetration across a polydimethylsiloxane membrane from theoretically derived molecular descriptors

Agatonovic-Kustrin S, Beresford R, Yusof AP

J Pharm Biomed Anal, 2001 Sep;26(2):241-54.

PMID: 11470201

A quantitative structure-permeability relationship was developed using Artificial Neural Network (ANN) modeling to study penetration across a polydimethylsiloxane membrane. A set of 254 compounds and their experimentally derived maximum steady state flux values used in this study was gathered from the literature. A total of 42 molecular descriptors were calculated for each compound. A genetic algorithm was used to select important molecular descriptors and supervised ANN was used to correlate selected descriptors with the experimentally derived maximum steady-state flux through the polydimethylsiloxane membrane (log J). Calculated molecular descriptors were used as the ANN's inputs and log J as the output. Developed model indicates that molecular shape and size, inter-molecular interactions, hydrogen-bonding capacity of drugs, and conformational stability could be used to predict drug absorption through skin. A 12-descriptor nonlinear computational neural network model has been developed for the estimation of log J values for a data set of 254 drugs. Described model does not require experimental parameters and could potentially provide useful prediction of membrane penetration of new drugs and reduce the need for actual compound synthesis and flux measurements.

Theoretically-derived molecular descriptors important in human intestinal absorption

Agatonovic-Kustrin S, Beresford R, Yusof AP

J Pharm Biomed Anal, 2001 May;25(2):227-37.

PMID: 11275432

A quantitative structure-human intestinal absorption relationship was developed using artificial neural network (ANN) modeling. A set of 86 drug compounds and their experimentally-derived intestinal absorption values used in this study was gathered from the literature and a total of 57 global molecular descriptors, including constitutional, topological, chemical, geometrical and quantum chemical descriptors, calculated for each compound. A supervised network with radial basis transfer function was used to correlate calculated molecular descriptors with experimentally-derived measures of human intestinal absorption. A genetic algorithm was then used to select important molecular descriptors. Intestinal absorption values (IA%) were used as the ANN's output and calculated molecular descriptors as the inputs. The best genetic neural network (GNN) model with 15 input descriptors was chosen, and the significance of the selected descriptors for intestinal absorption examined. Results obtained with the model that was developed indicate that lipophilicity, conformational stability and inter-molecular interactions (polarity, and hydrogen bonding) have the largest impact on intestinal absorption.

Prevalence and subtype distribution of Blastocystis sp. in cattle from Pahang, Malaysia

Kamaruddin SK, Mat Yusof A, Mohammad M

Trop Biomed, 2020 Mar 01;37(1):127-141.

PMID: 33612724

Blastocystis sp. is a common enteric protozoan parasite found in humans and various type of animal worldwide. Recently, genotypic distribution of Blastocystis sp. was revealed in insects, rodents, avian and mammals, which exposed its potential of transmiting the infections to human. However, very little information on current level of Blastocystis sp. infection were reported in cattle from Malaysia. Herein, a total of 120 stool samples of cattles were collected. While the potential risk of infection such as age, gender, body score, diarrheic condition of the cattle were noted, the management of the farms was also recorded. All stool sample were cultured, but 80 samples were selected for PCR sequencing analysis. The cultivation and microscopic examination revealed only 25% of the cattle (30/120) were infected with Blastocystis sp.. But, 43.8% of the cattle (35/80) were found positive upon PCR sequencing. The study also found that age, body score condition, diarrheic condition and certain farm were associated with the infection (p<0.05). Six subtypes (STs) that were discovered during the study were ST10 (21.3%;17/35), ST5 (8.8%;7/35), ST3 (7.5%;6/35), ST1 (2.5%;2/35), ST4 (2.5%;2/35) and ST14 (1.3%;1/35). Thus, moderate infections of Blastocystis sp. and variants in the genotypic distributions of the cattle suggest its potential for zoonotic transmission. Therefore, this findings could be helpful for further understanding the parasite, which assist studies of its pathogenicity.

The effect of 10 days of intermittent fasting on Wingate anaerobic power and prolonged high-intensity time-to-exhaustion cycling performance

Naharudin MNB, Yusof A

Eur J Sport Sci, 2018 Jun;18(5):667-676.

PMID: 29485326 DOI: 10.1080/17461391.2018.1438520

Many physically active individuals have undertaken intermittent fasting to reduce their daily caloric intake. However, abstaining from meals for a specific length of time may lead to the acute disturbance of highly carbohydrate-dependent exercise performance. The purpose of this study was to observe the effect of 10 days of intermittent fasting on high-intensity type exercises, Wingate anaerobic (WT) and prolonged high-intensity time-to-exhaustion (HIT) cycling test. Twenty participants were randomised into an intermittent fasting (FAS) and a control group (CON). One day after baseline data collection on Day-0 where participants consumed their recommended daily caloric intake (FAS = 2500 ± 143 kcal day-1; CON = 2492 ± 20 kcal day-1) served over a course of five meals, the FAS group consumed only four meals where 40% was restricted by the omission of lunch (FAS = 1500 ± 55 kcal day-1). This diet was then continued for 10 days. Data on exercise performance and other dependent variables were collected on Day-2, -4, -6, -8 and -10. A reduction in WT power in the FAS group was observed on Day-2 (821.74 ± 66.07 W) compared to Day-0 (847.63 ± 95.94 W) with a moderate effect size (p

Fulltext Awareness and prevalence of mammography screening and its predictors--a cross sectional study in a primary care clinic in Malaysia

Yusof A, Chia YC, Hasni YM

Asian Pac J Cancer Prev, 2014;15(19):8095-9.

PMID: 25338990

BACKGROUND: Worldwide, over half a million women died of breast cancer in 2011 alone. Mammography screening is associated with a reduction of 20 to 35% in breast cancer mortality. The aim of this study was to determine the awareness and practice of mammography screening and predictors of its uptake in Malaysian women attending a primary care clinic.

MATERIALS AND METHODS: A cross-sectional study was carried out among women aged 40 to 74 years attending a primary care clinic in Selangor, Malaysia. An assisted structured questionnaire included questions on socio-demography, source of information and level of knowledge. An adapted version of the revised Champion Health Belief Model Scale plus other associated factors for mammography screening up-take were also included as part of the questionnaire. Predictors for mammography screening uptake were only determined in those who were aware about mammography screening. Significant predictors were determined by logistic regression.

RESULTS: 447 women were recruited for this study; 99.1% of them (n: 411) were aware about breast cancer. Only 50.1% (n: 206) had knowledge about mammography screening. Prevalence of clinical breast-examination (CBE) was 23.3% (n: 104) and mammography screening up-take was 13.2% (n: 59). The predictors for the latter were those who have had clinical breast-examination (aOR=17.58, 95%CI: 7.68-39.82) and those aged between 50 to 59 years (aOR=3.94, 95%CI: 1.61-9.66) as well as those aged 60 years and above (aOR=6.91, 95%CI: 2.28-20.94). Good knowledge and positive beliefs about mammography screening were not associated with mammography screening uptake.

CONCLUSIONS: Half of our Malaysian women were aware about mammography screening. However, the uptake of mammography was low. Previous CBE and older age were significant predictors of mammography screening uptake. Increasing CBE services may increase compliance with guidelines.

Fulltext Testosterone reduces knee passive range of motion and expression of relaxin receptor isoforms via 5α-dihydrotestosterone and androgen receptor binding

Dehghan F, Muniandy S, Yusof A, Salleh N

Int J Mol Sci, 2014;15(3):4619-34.

PMID: 24642882 DOI: 10.3390/ijms15034619

Ovarian steroids such as estrogen and progesterone have been reported to influence knee laxity. The effect of testosterone, however, remains unknown. This study investigated the effect of testosterone on the knee range of motion (ROM) and the molecular mechanisms that might involve changes in the expression of relaxin receptor isoforms, Rxfp1 and Rxfp2 in the patella tendon and lateral collateral ligament of the female rat knee. Ovariectomized adult female Wistar rats received three days treatment with peanut oil (control), testosterone (125 and 250 μg/kg) and testosterone (125 and 250 μg/kg) plus flutamide, an androgen receptor blocker or finasteride, a 5α-reductase inhibitor. Duplicate groups received similar treatment however in the presence of relaxin (25 ng/kg). A day after the last drug injection, knee passive ROM was measured by using a digital miniature goniometer. Both tendon and ligament were harvested and then analysed for protein and mRNA expression for Rxfp1 and Rxfp2 respectively. Knee passive ROM, Rxfp1 and Rxfp2 expression were significantly reduced following treatment with testosterone. Flutamide or finasteride administration antagonized the testosterone effect. Concomitant administration of testosterone and relaxin did not result in a significant change in knee ROM as compared to testosterone only treatment; however this was significantly increased following flutamide or finasteride addition. Testosterone effect on knee passive ROM is likely mediated via dihydro-testosterone (DHT), and involves downregulation of Rxfp1 and Rxfp2 expression, which may provide the mechanism underlying testosterone-induced decrease in female knee laxity.

Acute toxicity tests on raw leachate from a Malaysian dumping site

Sujá F, Yusof A, Osman MA

Water Sci Technol, 2010;61(2):389-96.

PMID: 20107265 DOI: 10.2166/wst.2010.825

Leachate samples collected from the Ampar Tenang open dumping site at Dengkil, Malaysia, were analyzed for acute toxicity. Two in vivo toxicity tests, Acute Oral Toxicity (AOT) and Primary Skin Irritation (PSI), were performed using Sprague Dawley rats and New Zealand Albino rabbits, respectively. The leachate samples were also analyzed chemically for nitrate and phosphate, ammonia-nitrogen, Kjeldahl-nitrogen and Chemical Oxygen Demand (COD). Results from both the AOT and PSI tests showed that the leachate did not contribute to acute toxicity. The AOT test yielded a negative result: no effect was observed in at least half of the rat population. The PSI test on rabbits produced effects only at a leachate concentration of 100%. However, the skin irritation was minor, and the test returned a negative result. The four chemical tests showed high levels of nutrient pollution in the leachate. The nitrate and phosphate concentrations were 2.1 mg/L and 23.6 mg/L, respectively. Further, the ammonia-nitrogen concentration was 1,000 mg NH(3)-N/L the Kjeldahl-nitrogen level was 446 mg NH(3)-N/L, and the Chemical Oxygen Demand was 1,300 mg/L. The in vivo toxicity and chemical analyses showed that the leachate is polluted but not acutely toxic to organisms.

The kinin antagonist hoe 140 reduces acute paw oedema in rats caused by carrageenan, bradykinin and kaolin

Sharma JN, Yusof AP, Wirth KJ

Inflammopharmacology, 1998;6(1):9-17.

PMID: 17638123

The present study aimed to evaluate the effect of Hoe 140, a BK receptor B(2) antagonist, on acute oedema induced by carrageenan, BK and kaolin in male Wistar Kyoto rats. Hoe 140 (0.2 mg/kg and 20 mg/kg) given ip caused significant (p<0.05 and p<0.01) inhibition of carrageenan and BK-induced paw oedema. This suggests that BK is the prime inflammatory mediator of carrageenan oedema, and that it is also a specific blocker of oedema caused by BK. Furthermore, Hoe 140 was found to be less effective in reducing kaolin-induced oedema in rats. This might reflect that BK is not a prime inflammatory mediator of kaolin-induced oedema. The possible significance of these findings is discussed.

Estrogen receptor (ER)-α, β and progesterone receptor (PR) mediates changes in relaxin receptor (RXFP1 and RXFP2) expression and passive range of motion of rats' knee

Dehghan F, Yusof A, Muniandy S, Salleh N

Environ Toxicol Pharmacol, 2015 Nov;40(3):785-91.

PMID: 26447688 DOI: 10.1016/j.etap.2015.09.004

The high risk of knee injuries in female may be associated with sex-steroid hormone fluctuations during the menstrual cycle by its effect on ligaments and tendons stiffness. This study examined changes in knee range of motion in presence of estrogen and progesterone and investigated the interaction of their antagonists to relaxin receptors.

Speciation of inorganic arsenic and selenium in leachates from landfills in relation to water quality assessment

Yusof AM, Salleh S, Wood AK

Biol Trace Elem Res, 1999;71-72:139-48.

PMID: 10676488

Speciation of arsenic and selenium was carried out on water samples taken from rivers used as water intake points in the vicinity of landfill areas used for land-based waste disposal system. Leachates from these landfill areas may contaminate the river water through underground seepage or overflowing, especially after a heavy downpour. Preconcentration of the chemical species was done using a mixture of ammonium pyrrolidinethiocarbamate-chloroform (APDTC-CHCl3). Because only the reduced forms of both arsenic and selenium species could be extracted by the preconcentrating mixture, suitable reducing agents such as 25% sodium thiosulfate for As(III) and 6M HCl for Se(IV) were used throughout the studies. Care was taken to exclude the interfering elements such as the alkali and alkali earth metals from the inorganic arsenic and selenium species by introducing 12% EDTA solution as the masking agent. The extracted mixture was irradiated in a thermal neutron flux of 4 x 10(12)/cm/s from a TRIGA Mk.II reactor at the Malaysia Institute of Nuclear Technology Research (MINT). Gamma rays of 559 keV and 297 keV from 76As and 75Se, respectively, were used in the quantitative determination of the inorganic species. Mixed standards of As(III) and Se(IV) used in the percentage efficiency procedure were prepared from salts of Analar grade. The water quality evaluation was viewed from the ratio of the inorganic species present.

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