MyMedR

Fulltext Polymerization degrees, molecular weights and protein-binding affinities of condensed tannin fractions from a Leucaena leucocephala hybrid

Saminathan M, Tan HY, Sieo CC, Abdullah N, Wong CM, Abdulmalek E, et al.

Molecules, 2014 Jun 12;19(6):7990-8010.

PMID: 24927368 DOI: 10.3390/molecules19067990

Condensed tannins (CTs) form insoluble complexes with proteins and are able to protect them from degradation, which could lead to rumen bypass proteins. Depending on their degrees of polymerization (DP) and molecular weights, CT fractions vary in their capability to bind proteins. In this study, purified condensed tannins (CTs) from a Leucaena leucocephala hybrid were fractionated into five different molecular weight fractions. The structures of the CT fractions were investigated using 13C-NMR. The DP of the CT fractions were determined using a modified vanillin assay and their molecular weights were determined using Q-TOF LC-MS. The protein-binding affinities of the respective CT fractions were determined using a protein precipitation assay. The DP of the five CT fractions (fractions F1-F5) measured by the vanillin assay in acetic acid ranged from 4.86 to 1.56. The 13C-NMR results showed that the CT fractions possessed monomer unit structural heterogeneity. The number-average molecular weights (Mn) of the different fractions were 1265.8, 1028.6, 652.2, 562.2, and 469.6 for fractions F1, F2, F3, F4, and F5, respectively. The b values representing the CT quantities needed to bind half of the maximum precipitable bovine serum albumin increased with decreasing molecular weight--from fraction F1 to fraction F5 with values of 0.216, 0.295, 0.359, 0.425, and 0.460, respectively. This indicated that higher molecular weight fractions of CTs from L. leucocephala have higher protein-binding affinities than those with lower molecular weights.

Modulatory effects of condensed tannin fractions of different molecular weights from a Leucaena leucocephala hybrid on the bovine rumen bacterial community in vitro

Saminathan M, Sieo CC, Gan HM, Ravi S, Venkatachalam K, Abdullah N, et al.

J Sci Food Agric, 2016 Oct;96(13):4565-74.

PMID: 26910767 DOI: 10.1002/jsfa.7674

BACKGROUND: Condensed tannin (CT) fractions of different molecular weights (MWs) may affect rumen microbial metabolism by altering bacterial diversity. In this study the effects of unfractionated CTs (F0) and five CT fractions (F1-F5) of different MWs (F1, 1265.8 Da; F2, 1028.6 Da; F3, 652.2 Da; F4, 562.2 Da; F5, 469.6 Da) from Leucaena leucocephala hybrid-Rendang (LLR) on the structure and diversity of the rumen bacterial community were investigated in vitro.

RESULTS: Real-time polymerase chain reaction assay showed that the total bacterial population was not significantly (P > 0.05) different among the dietary treatments. Inclusion of higher-MW CT fractions F1 and F2 significantly (P

Development of a semidefined growth medium for Pedobacter cryoconitis BG5 using statistical experimental design

Ong M, Ongkudon CM, Wong CM

Prep Biochem Biotechnol, 2016 Oct 02;46(7):657-65.

PMID: 26759918 DOI: 10.1080/10826068.2015.1135447

Pedobacter cryoconitis BG5 are psychrophiles isolated from the cold environment and capable of proliferating and growing well at low temperature regime. Their cellular products have found a broad spectrum of applications, including in food, medicine, and bioremediation. Therefore, it is imperative to develop a high-cell density cultivation strategy coupled with optimized growth medium for P. cryoconitis BG5. To date, there has been no published report on the design and optimization of growth medium for P. cryoconitis, hence the objective of this research project. A preliminary screening of four commercially available media, namely tryptic soy broth, R2A, Luria Bertani broth, and nutrient broth, was conducted to formulate the basal medium. Based on the preliminary screening, tryptone, glucose, NaCl, and K2HPO4 along with three additional nutrients (yeast extract, MgSO4, and NH4Cl) were identified to form the basal medium which was further analyzed by Plackett-Burman experimental design. Central composite experimental design using response surface methodology was adopted to optimize tryptone, yeast extract, and NH4Cl concentrations in the formulated growth medium. Statistical data analysis showed a high regression factor of 0.84 with a predicted optimum optical (600 nm) cell density of 7.5 using 23.7 g/L of tryptone, 8.8 g/L of yeast extract, and 0.7 g/L of NH4Cl. The optimized medium for P. cryoconitis BG5 was tested, and the observed optical density was 7.8. The cost-effectiveness of the optimized medium was determined as 6.25 unit prices per gram of cell produced in a 250-ml Erlenmeyer flask.

Sudden death during jungle trekking: a case of heat stroke

Nadesan K, Chan SP, Wong CM

Malays J Pathol, 1998 Jun;20(1):49-54.

PMID: 10879265

Heat stroke, which is also known as "sun stroke," is a medical emergency, and fatalities can occur unless it is diagnosed early and treated efficiently. Heat stroke may manifest quite suddenly, giving little time to differentiate it from extreme physical exhaustion in collapsed subjects. It is also known to lead to serious disseminated intravascular coagulation. Sudden death in a young female is presented who collapsed after trekking in a hilly, jungle area in Malaysia on a warm, humid day. She had joined a weight reduction programme a few weeks earlier. She was found collapsed and in a semiconscious state in the jungle by her groupmates and was taken to hospital. On admission she was unconscious, hyperpyrexic, with rapid, thready pulse and a low blood pressure. Biochemical studies revealed metabolic acidosis, elevated liver and cardiac enzymes and impairment of renal function. Her coagulation profile was found to be impaired and she started bleeding through the mouth and nostrils. She also developed watery diarrhoea and initially a septicaemic condition, including acute enteritis was suspected. Despite active treatment, her condition deteriorated and she died eight hours after admission. Autopsy confirmed a generalised bleeding tendency, with pulmonary, oesophageal and gastrointestinal mucosal haemorrhages. Flame-shaped subendocardial shock haemorrhages were seen in the interventricular septum on the left side of the heart. The findings support a diagnosis of heat stroke. Various aspects related to heat stroke, the autopsy diagnosis and its prevention are discussed.

Fulltext A Study of Dielectric Properties of Proteinuria between 0.2 GHz and 50 GHz

Mun PS, Ting HN, Ong TA, Wong CM, Ng KH, Chong YB

PLoS One, 2015;10(6):e0130011.

PMID: 26066351 DOI: 10.1371/journal.pone.0130011

This paper investigates the dielectric properties of urine in normal subjects and subjects with chronic kidney disease (CKD) at microwave frequency of between 0.2 GHz and 50 GHz. The measurements were conducted using an open-ended coaxial probe at room temperature (25°C), at 30°C and at human body temperature (37°C). There were statistically significant differences in the dielectric properties of the CKD subjects compared to those of the normal subjects. Statistically significant differences in dielectric properties were observed across the temperatures for normal subjects and CKD subjects. Pearson correlation test showed the significant correlation between proteinuria and dielectric properties. The experimental data closely matched the single-pole Debye model. The relaxation dispersion and relaxation time increased with the proteinuria level, while decreasing with the temperature. As for static conductivity, it increased with proteinuria level and temperature.

The use of freeze-dry bovine pericardium (FDBP) in diaphragmatic herniorrhaphy in dogs

Loqman MY, Wong CM, Hair-Bejo M, Zuki AB, Hafeez YM

Med J Malaysia, 2004 May;59 Suppl B:113-4.

PMID: 15468844

A study was conducted to investigate the effectiveness of freeze-dried bovine pericardium (FDBP) as a biomaterial in diaphragmatic herniorrhapy in dogs. Eight adult dogs were randomly selected and divided into two equal groups. In FDBP group, a diaphragmatic defect was induced and repaired with an identical size of FDBP. In the control group, a diaphragmatic wall was incised at three-side border creating a flap and sutured. Grossly, only mild intrathoracic adhesion was observed for most of the animals, and no herniation occured. Microscopically, the biomaterial incorporated into the host's tissue by ingrowth of young muscle fiber and massive new blood vessel formation in between the fibrous tissue.

The systematic position of Hypsugo macrotis (Chiroptera: Vespertilionidae) and a new record from Peninsular Malaysia

Lim LS, Csorba G, Wong CM, Zubaid A, Rahman SP, Kumaran JV, et al.

Zootaxa, 2016 Sep 22;4170(1):169-177.

PMID: 27701281 DOI: 10.11646/zootaxa.4170.1.10

The Southeast Asian species of Hypsugo are rare bats, except for H. cadornae and H. pulveratus, which are distributed throughout the Indomalayan region. Hypsugo macrotis is restricted to Peninsular Malaysia, Sumatra, Java and adjacent islands, and is known only from a handful of specimens. Here we report a new locality record of the species from Seremban, Peninsular Malaysia, which also represents the first known building-dweller colony of any Hypsugo from the region. We discuss the taxonomic status of two morphologically similar species, H. macrotis and H. vordermanni, and provide the first COI and cyt b gene sequences for H. macrotis and reconstruct the species' phylogenetic relationships.

An unusual cause of secondary spontaneous pneumothorax in a 27-year-old man

Lim KH, Tan LH, Liam CK, Wong CM

Chest, 2001 Nov;120(5):1728-31.

PMID: 11713160

Giant cell arteritis presenting as chronic cough and prolonged fever

Lim KH, Liam CK, Vasudevan AE, Wong CM

Respirology, 1999 Sep;4(3):299-301.

PMID: 10489679 DOI: 10.1046/j.1440-1843.1999.00195.x

A 62-year-old man presented with a 3-month history of chronic non-productive cough and unexplained fever. Further questioning revealed that he had headaches and myalgia. Bilateral thickened temporal arteries were noted on physical examination. The erythrocyte sedimentation rate was 96 mm in 1 h. A biopsy specimen of the left temporal artery showed inflammatory changes consistent with the diagnosis of giant cell arteritis. Commencement of prednisolone resulted in rapid and dramatic resolution of his symptoms. Physicians should be aware of respiratory symptoms in patients with giant cell arteritis in order to avoid delay in diagnosis and therapy of this condition.

A 52-year-old woman with recurrent hemoptysis

Lim KH, Lim YC, Liam CK, Wong CM

Chest, 2001 Mar;119(3):955-7.

PMID: 11243981

A patient presenting with hoarseness. Diagnosis: sarcoidosis

Lim KH, Liam CK, Wong CM

Postgrad Med J, 2000 Aug;76(898):512, 518-9.

PMID: 10908387

Community-acquired pneumonia in patients requiring hospitalization

Liam CK, Lim KH, Wong CM

Respirology, 2001 Sep;6(3):259-64.

PMID: 11555386

This study aimed to investigate the microbial aetiology of community-acquired pneumonia (CAP) in patients requiring hospitalization.

Fulltext Acceptance of the Accuhaler, a multi-dose powder inhaler, among asthmatic patients: a comparison with the pressurized metered-dose inhaler

Liam CK, Lim KH, Wong CM

Asian Pac J Allergy Immunol, 2000 Sep;18(3):135-40.

PMID: 11270467

This study aimed to evaluate dry powder inhaler naive asthmatic patients' perception and preference of the Accuhaler, a multidose dry powder inhaler and the pressurized metered dose inhaler (pMDI). After the first instruction, 66.7% of 48 patients enrolled in the study could demonstrate the correct use of the Accuhaler. When the patients were asked to compare the pMDI and the Accuhaler after using the Accuhaler to administer salmeterol for 4 weeks, the Accuhaler scored significantly better than the pMDI for the following features: knowing how many doses are left, presence of an attached cover, taste, instruction for use, attractiveness, ease of use, ease of holding, shape, and comfortable mouthpiece. The pMDI scored better to the Accuhaler in terms of size. More patients preferred the Accuhaler than the pMDI; the presence of a dose counter and perceived ease of use were the main reasons cited for their preference for the Accuhaler.
Study site: Asthma Clinic, University of Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia

Fulltext Relationship between symptoms and objective measures of airway obstruction in asthmatic patients

Liam CK, Goh CT, Isahak M, Lim KH, Wong CM

Asian Pac J Allergy Immunol, 2001 Jun;19(2):79-83.

PMID: 11699724

The objective of this study was to determine the relationship between asthma symptoms and the degree of airway obstruction as measured by the forced expiratory volume in one second (FEV1) and peak expiratory flow rate (PEFR) in a group of 64 asthmatic patients with clinically stable disease attending a university-based urban asthma clinic. Asthma symptoms did not correlate with the degree of airway obstruction as measured by prebronchodilator PEFR (total asthma symptom score vs PEFR: r = -0.214, p = 0.104, n = 59) and only correlated poorly with prebronchodilator FEV1 (total asthma symptom score vs FEV1: r = -0.256, p = 0.041, n = 64). These results lend support to the recommendation that airway obstruction should be measured objectively when assessing patients with chronic persistent asthma.
Study site: Asthma clinic, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia

Tuberculous pleurisy as a manifestation of primary and reactivation disease in a region with a high prevalence of tuberculosis

Liam CK, Lim KH, Wong CM

Int J Tuberc Lung Dis, 1999 Sep;3(9):816-22.

PMID: 10488891

A teaching hospital in Malaysia.

Fulltext Attitudes and knowledge of newly diagnosed tuberculosis patients regarding the disease, and factors affecting treatment compliance

Liam CK, Lim KH, Wong CM, Tang BG

Int J Tuberc Lung Dis, 1999 Apr;3(4):300-9.

PMID: 10206500

SETTING: An urban university teaching hospital.
OBJECTIVES: To determine patients' attitudes to tuberculosis and their knowledge of the disease, and factors associated with treatment compliance.
DESIGN: All adult patients commenced on treatment for tuberculosis from September 1994 to February 1996 were interviewed on initiation of treatment. To assess patient compliance with treatment, hospital clinical records were reviewed retrospectively.
RESULTS: A total of 135 patients with a mean age (±SD) of 41.9 (±17.4) years (range 15–84 years) were interviewed. The patients had limited understanding and knowledge about tuberculosis. There was a negative correlation between patient age and tuberculosis knowledge score (r = −0.18, P = 0.038). Patients with tertiary education had better knowledge than the others. Of 118 patients who were followed-up in our chest clinic, 80 (67.8%) completed the prescribed treatment. Compliance with treatment and follow-up was not affected by age, sex, ethnic group, educational level, occupation, extent of knowledge, tuberculosis symptoms, hospitalisation for tuberculosis or duration of the prescribed treatment regimen. There was a trend toward poorer compliance among patients who equated disappearance of tuberculosis symptoms with cure of the disease.
CONCLUSIONS: Malaysian patients with newly diagnosed tuberculosis attending a university teaching hospital had misconceptions and limited knowledge about the disease and its treatment. Educational background was an important determinant of a patient's level of knowledge about tuberculosis. Compliance was not affected by patient characteristics. Adequate counselling and education of patients and close relatives on tuberculosis and the necessity for prolonged treatment may help to improve treatment compliance.
Study site: Chest clinic, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia

Causes of pleural exudates in a region with a high incidence of tuberculosis

Liam CK, Lim KH, Wong CM

Respirology, 2000 Mar;5(1):33-8.

PMID: 10728729

To define the causes of exudative pleural effusions in our region.

Lung cancer in patients younger than 40 years in a multiracial Asian country

Liam CK, Lim KH, Wong CM

Respirology, 2000 Dec;5(4):355-61.

PMID: 11192546

This study aimed to determine whether the clinicopathological features of lung cancer in patients younger than 40 years differ from that of older patients in an Asian country.

Non-small cell lung cancer in very young and very old Malaysian patients

Liam CK, Lim KH, Wong CM

Chest, 2002 Jan;121(1):309-10.

PMID: 11796481

Skin prick test reactivity to common aeroallergens in asthmatic patients with and without rhinitis

Liam CK, Loo KL, Wong CM, Lim KH, Lee TC

Respirology, 2002 Dec;7(4):345-50.

PMID: 12421243 DOI: 10.1046/j.1440-1843.2002.00409.x

OBJECTIVE: The aim of this study was to investigate the prevalence of skin prick test (SPT) reactivity to common aeroallergens among Malaysian asthmatic patients with and without rhinitis.
METHODOLOGY: An SPT using eight aeroallergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae, cat fur, cockroach, Acacia sp., Bermuda grass, Aspergillus fumigatus and Aspergillus niger) was performed on 206 asthmatic patients.
RESULTS: One hundred and forty patients (68%) were reactive to at least one of the aeroallergens. Among the SPT-positive patients, a positive prick test reaction to the house dust mites, D. pteronyssinus (93.6%), and D. farinae (81.4%) was most common, followed by cat fur (20.0%), cockroach (7.9%), Bermuda grass (7.9%), Acacia sp. (7.9%), A. fumigatus (0.7%) and A. niger (0.7%). A history of rhinitis was elicited in 111 (53.9%) patients and 95 (85.3%) of these patients were SPT-positive compared with only 45 (47.4%) of 95 patients with asthma symptoms alone (P < 0.001). The presence of rhinitis and a young age of onset of asthma were independent factors for positive SPT reaction to at least one of the aeroallergens.
CONCLUSIONS: The prevalence of SPT reactivity to common aeroallergens is high among Malaysian asthmatics, particularly in those with an early age of onset and in those with coexisting rhinitis.
Study site: Asthma Clinic, University of Malaya Medical Centre, Kuala Lumpur, Malaysia

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