MyMedR

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.

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.

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 Dengue antibodies in a suburban community in Malaysia

Chen WS, Wong CH, Cillekens L

Med J Malaysia, 2003 Mar;58(1):142-3.

PMID: 14556343

Evaluating the quality of images produced by soft X-ray units

Bradley DA, Wong CS, Ng KH

Appl Radiat Isot, 2000 9 26;53(4-5):691-7.

PMID: 11003508

For broad-beam soft X-ray sources, assessment of the quality of image produced by such units is made complex by the low penetration capabilities of the radiation. In the present study we have tested the utility of several types of test tool, some of which have been fabricated by us, as part of an effort to evaluate several key image defining parameters. These include the film characteristic, focal-spot size, image resolution and detail detectability. The two sources of X-rays used in present studies were the University of Malaya flash X-ray device (UMFX1) and a more conventional soft X-ray tube (Softex, Tokyo), the latter operating at peak accelerating potentials of 20 kVp. We have established, for thin objects, that both systems produce images of comparable quality and, in particular, objects can be resolved down to better than 45 microm.

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.

Massive pleural effusions in cryptococcal meningitis

Wong CM, Lim KH, Liam CK

Postgrad Med J, 1999 May;75(883):297-8.

PMID: 10533638

Cryptococcal infection uncommonly presents with pulmonary manifestations and even more rarely so as massive bilateral effusions. Pleural involvement is usually associated with underlying pulmonary parenchymal lesions and is unusual while on antifungal therapy. We report a patient with cryptococcal meningitis who, while on intravenous 5-flucytosine and amphotericin B, developed life-threatening bilateral massive pleural effusions with evidence of spontaneous resolution, consistent with prior hypothesis of antigenic stimulation as the cause of pleural involvement.

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.

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

Fulltext Ectopic pregnancy: uncommon presentations and difficulty in diagnosis

Wong CM, Ganesh R, Ng KY

Med J Malaysia, 1999 Mar;54(1):117-9.

PMID: 10972015

Diagnosis of ectopic pregnancy prior to rupture is an arduous task even with the availability of many new investigative methods and imaging modalities. Above all, a high index of suspicion is necessary when dealing with women who present in early pregnancy with abdominal pain and vaginal bleeding. With the increased use of ovulation induction agents, the probability of heterotropic pregnancy should be kept in mind. The use of transvaginal ultrasonography (TVS) will help in earlier diagnosis because of its advantages over transabdominal ultrasonography (TAS).

Fulltext Leucostasis: an uncommon cause of respiratory distress

Goh KL, Bosco J, Wong CS

Med J Malaysia, 1983 Sep;38(3):194-6.

PMID: 6584709

Simple high-performance liquid chromatographic method for the determination of ranitidine in human plasma

Wong CF, Peh KK, Yuen KH

J Chromatogr B Biomed Sci Appl, 1998 Oct 23;718(1):205-10.

PMID: 9832378

A simple high-performance liquid chromatographic method was developed for the determination of ranitidine in human plasma. Prior to analysis, ranitidine and the internal standard (metoprolol) were extracted from alkalinized plasma samples using dichloromethane. The mobile phase was 0.05 M potassium dihydrogenphosphate-acetonitrile (88:12, v/v) adjusted to pH 6.5. Analysis was run at a flow-rate of 1.3 ml/min and at a detection wavelength of 229 nm. The method is sensitive with a detection limit of 1 ng/ml at a signal-to-noise ratio of 3:1, while the quantification limit was set at 15 ng/ml. The calibration curve was linear over a concentration range of 15-2000 ng/ml. Mean recovery value of the extraction procedure was about 90%, while the within-day and between-day coefficients of variation and percent error values of the assay method were all less than 15%.

An in-vitro method for buccal adhesion studies: importance of instrument variables

Wong CF, Yuen KH, Peh KK

Int J Pharm, 1999 Mar 25;180(1):47-57.

PMID: 10089291

A method using a texture analyzer equipment and chicken pouch as the biological tissue was investigated for measuring the bioadhesive properties of polymers under simulated buccal conditions. The method was evaluated using two polymers, namely Carbopol 974P and Methocel K4M while the instrument variables studied included the contact force, contact time and speed of withdrawal of the probe from the tissue. The parameters measured were the work of adhesion and peak detachment force. Longer contact time and faster probe speed not only gave better reproducibility of results, but also better sensitivities for both parameters measured. On the other hand, a certain level of contact force was found essential for achieving good bioadhesion, above which there was no further contribution to the bioadhesion process. When the method was applied to determine the bioadhesiveness of several polymers, the values obtained for the work of adhesion and peak detachment force were quite consistent in the ranking of the polymers. The Carbopols were found to have the highest values, followed by gelatin, sodium carboxymethyl celluloses and hydroxypropylmethyl celluloses. On the other hand, Alginic acid, Eudragit RLPO and RSPO, and Chitosan appeared to have low bioadhesive values.

Formulation and evaluation of controlled release Eudragit buccal patches

Wong CF, Yuen KH, Peh KK

Int J Pharm, 1999 Feb 01;178(1):11-22.

PMID: 10205621

Controlled release buccal patches were fabricated using Eudragit NE40D and studied. Various bioadhesive polymers, namely hydroxypropylmethyl cellulose, sodium carboxymethyl cellulose and Carbopol of different grades, were incorporated into the patches, to modify their bioadhesive properties as well as the rate of drug release, using metoprolol tartrate as the model drug. The in-vitro drug release was determined using the USP 23 dissolution test apparatus 5 with slight modification, while the bioadhesive properties were evaluated using texture analyzer equipment with chicken pouch as the model tissue. The incorporation of hydrophilic polymers was found to affect the drug release as well as enhance the bioadhesiveness. Although high viscosity polymers can enhance the bioadhesiveness of the patches, they also tend to cause non-homogeneous distribution of the polymers and drug, resulting in non-predictable drug-release rates. Of the various bioadhesive polymers studied, Cekol 700 appeared to be most satisfactory in terms of modifying the drug release and enhancement of the bioadhesive properties.

Fulltext Plasma-derived microparticles in polycythaemia vera

Ahadon M, Abdul Aziz S, Wong CL, Leong CF

Malays J Pathol, 2018 Apr;40(1):41-48.

PMID: 29704383 MyJurnal

INTRODUCTION: Microparticles are membrane bound vesicles, measuring less than 1.0 um, which are released during cellular activation or during apoptosis. Studies have shown that these circulating microparticles play a role in coagulation, cell signaling and cellular interactions. Increased levels of circulating microparticles have been observed in a number of conditions where there is vascular dysfunction, thrombosis and inflammation. The objective of this study was to determine the various plasma-derived microparticles in patients with polycythaemia vera (PV) in Universiti Kebangsaan Malaysia Medical Centre and to compare them with normal control.

METHODS: A total of 15 patients with PV and 15 healthy volunteers were included in this cross-sectional descriptive study. Plasma samples from both patients and healthy volunteers were prepared and further processed for isolation of microparticles. Flow cytometry analyses were then carried out in all samples to determine the cellular origin of the microparticles. Full blood count parameters for both groups were also collected. Data collected were analyzed using SPSS version 12.0.

RESULTS: Patients with PV had a significantly higher percentage of platelet derived microparticles compared to healthy controls (P <0.05). The control group had a higher level of endothelial derived microparticles but the differences were not statistically significant (P > 0.05).

CONCLUSION: The median percentage of positive events for platelet derived microparticles was higher in patients with PV compared to normal healthy controls.

Possible mechanism for drug retardation from glyceryl monostearate matrix system

Peh KK, Wong CF, Yuen KH

Drug Dev Ind Pharm, 2000 Apr;26(4):447-50.

PMID: 10769787

Lipophilicity was evaluated as a possible mechanism for drug retardation from a glyceryl monostearate matrix system. Lipophilicity of the glyceryl monostearate matrix system was studied using contact angle measurement of water droplets on the surface of compressed disks, extrudate ascension of water, and movement of water through a powder mixture packed in a high-performance liquid chromatographic (HPLC) column. Increase in glyceryl monostearate content resulted in an increase in water droplet contact angle, decrease in the rate of water ascending the extrudate, and increase in the pressure values as a function of flow rate of water moving through the powder mixture. These could be due to the increase in lipophilicity of the matrix, rendering the matrix less wettable. As a result, the rate of water penetration into the matrix decreased, and the drug release could be sustained.

Mechanisms contributing to differential sensitivities of plants to SO2

Klein H, Jäger HJ, Domes W, Wong CH

Oecologia, 1978 Jan;33(2):203-208.

PMID: 28309164 DOI: 10.1007/BF00344848

SO2-fumigation experiments were conducted with plants of pea (Pisum sativum) and corn (Zea mays) recognized to be, respectively, sensitive and tolerant to the gas. Accumulation of inorganic sulfur in the tissues revealed that the pea takes up considerably greater amounts of SO2 than corn. Porometer measurements and transpiration coefficients show that this greater SO2 uptake is partly related to the lower leaf diffusion resistance of peas. Additional internal sinks for SO2 uptake are discussed in order to give a complete explanation of the differential SO2 uptake of the two species.

Fulltext Tumour seeding following percutaneous needle biopsy of hepatocellular carcinoma

Qua CS, Wong CH, Goh KL

Singapore Med J, 2008 Jan;49(1):e8-11.

PMID: 18204759

We report a hepatocellular carcinoma seeding following needle biopsy in a 57-year-old man who first presented with a focal hepatic lesion at another hospital. The patient had been a hepatitis B carrier for 20 years. Initial surveillance ultrasonography showed a lesion in segment IV, in the background of non-cirrhotic liver and normal serum alpha-foetoprotein level (8 ng/ml). A percutaneous needle biopsy was done and histopathology confirmed well-differentiated hepatocellular carcinoma. The patient had refused surgery and preferred to try traditional medicine. He presented to us four months after the initial biopsy with epigastric swelling. This was found to be due to a tumour seeding along the previous biopsy tract. He was given radiofrequency ablation (RFA) of tumour along the needle tract, in addition to the primary tumour. We conclude that the need for percutaneous needle biopsy should be critically evaluated in patients presenting with focal hepatic lesions and the role of RFA in treating tumour seeding needs further evaluation.

Fulltext Dural tear post mastoidectomy repaired with Dura Gen

Wong CY, Khairi MD, Mohamed SA, Irfan M

Med J Malaysia, 2010 Dec;65(4):307-8.

PMID: 21901952

Dural exposure may occur during the course of thinning the tegmen tympani and tegmen mastoideum in mastoid procedure. If large area of dura is exposed or lacerated, cerebrospinal fluid and brain herniation may enter the mastoid cavity. We report a case of a patient with injured dura mater and tegmen mastoideum during mastoidectomy for chronic suppurative otitis media with cholesteatoma managed by using DuraGen. The dura mater and tegmen defect healed totally showing the success of the procedure. A collagen matrix like DuraGen is an option for repairing dural tear in mastoid region.

Gastro-oesophageal reflux disease in chronic laryngitis: prevalence and response to acid-suppressive therapy

Qua CS, Wong CH, Gopala K, Goh KL

Aliment Pharmacol Ther, 2007 Feb 1;25(3):287-95.

PMID: 17269990

Gastro-oesophageal reflux is thought to cause chronic laryngitis through laryngopharyngeal reflux. Response of laryngitis to treatment with acid-suppressive therapy supports this causal link.

Fulltext Gastro-oesophageal reflux disease in 'difficult-to-control' asthma: prevalence and response to treatment with acid suppressive therapy

Wong CH, Chua CJ, Liam CK, Goh KL

Aliment Pharmacol Ther, 2006 May 1;23(9):1321-7.

PMID: 16629937 DOI: 10.1111/j.1365-2036.2006.02888.x

BACKGROUND: The causal association between gastro-oesophageal reflux disease (GERD) and difficult-to-control asthma is unclear.
AIM: To determine the prevalence of GERD and response to proton pump inhibitor therapy in patients with difficult-to-control asthma.
METHODS: Consecutive patients with difficult-to-control asthma as defined by persistent and recurrent symptoms despite on optimal asthmatic medications were recruited for the study. GERD was diagnosed by symptoms, gastroscopy and 24-h oesophageal pH monitoring. All patients were prescribed a course of lansoprazole 30 mg daily for 8 weeks. Improvement to treatment was assessed by a change in pulmonary symptom score and also by patient's subjective assessment of improvement.
RESULTS: Seventeen of 30 (56.7%) patients with difficult-to-control asthma were diagnosed with GERD. Pulmonary symptom score improved significantly only in patients with GERD (35.0 to 21.0; P = 0.002). Twelve of 16 (75%) patients with GERD reported an improvement in asthma symptoms; 1 of 11 (9.1%) without GERD reported mild symptom improvement. There was no significant change in peak expiratory flow rate and forced expiratory volume.
CONCLUSIONS: More than half of patients with difficult-to-control asthma were diagnosed with GERD. In these patients the severity of asthma improved significantly with potent acid suppression therapy. This underlines the critical role of acid reflux in this subset of patients with difficult-to-control asthma.
Study site: Respiratory clinic, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia

Displaying publications 21 - 40 of 97 in total