Introduction: Constipation is affecting a quarter of human population at any one time in all age groups. However, a proper gamma scintigraphic study of whole GI transit is rarely performed in Malaysia due to the lack of suitable radiopharmaceutical. Hence, this study was taken to develop a suitable radiotracer formulation for gamma scintigraphy study of whole gastric-intestinal transit. Methods: The biocompatible polystyrene (PS) incorporated with 152Sm2O3 (5%, w/v) will be used to synthesize the radiotracer. The 152Sm-labelled PS particles was neutron activated to 153Sm in a nuclear reactor for 5 minutes. Characterization of the physicochemical properties, gamma spectrometry and in-vitro radiolabeling studies in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) were carried out to study the properties and stability of the radiotracer before and after neutron activation. Results: Scanning electron microscope (SEM) and particle size analysis showed that size, shape and surface morphology of the particles remained after neutron activation. The synthesized 153Sm-labelled PS radiotracer (100 mg) particles achieved an activity of 3.7 MBq after 46 hrs. As indicated by the gamma spectrometry result, there is no long half-life radioimpuirties present in the samples. The 153Sm-labelled PS particles achieved radiolabeling efficiency of more than 95% in both SGF and SIF over 72 hrs. Conclusions: A 153Sm-labelled radiotracer particles formulation has been successfully developed from biocompatible PS. The proposed formulation has the advantage of cheaper, easier to be produced and reduced radiation exposure to staff. Further studies are required to validate the in-vivo performance of 153Sm-labelled formulation for assessing GI motility and transit in clinical use.
Introduction: Cancer has become a major economic and societal burden. The National Cancer Registry of Malaysia (NCR) estimates that one in four Malaysian (1:4) will develop cancer by the age of 75. This project aims to develop a prototype named “Laser ablation needle” for tissue cauterization and percutaneous hyperthermia cancer therapy. Our ultimate goal is to develop a highly flexible, operator-friendly and cost-effective laser ablation needle for tissue cauterization and hyperthermia cancer therapy, hence to improve the overall cancer survival rate and quality of life among the cancer patient population. Methods: The laser ablation needle is a closed loop opto-electronic control system, consists of a 2 mm Fiber Bragg Grating (FBG) – optical fiber temperature sensor, a laser driven hot needle and a micro-controller. Based on real-time temperature input from the FBG sensor, the micro-controller can perform a dynamic PID control on laser intensity for a safe hyperthermia treatment. In the fabrication, a medical grade optical fiber with a diameter of 800 μm was used for laser delivery. The optical fiber was embedded inside a biocompatible resin-made needle and connected to a 450 nm high power blue laser diode. The FBG temperature sensor was incorporated in the needle for real-time temperature monitoring and control. Focal hyperthermia produced by the laser-driven hot needle was conducted on ex-vivo bovine liver. Results: The rise in temperature was recorded by increasing laser power. The temperature profile was obtained at each depth. Irreversible thermal denaturation during irradiation was captured. Conclusion: These preliminary results suggest that this technique can be applied safely and effectively for cancer treatment. The developed prototype comprised of the diode laser showed that it can deliver its energy via simple optical fiber. This laser is cheaper and much smaller than the conventional high power lasers used in other studies.
Introduction: Hepatic radioembolization is a minimally invasive procedure involving intrarterial administration of radioembolic microspheres for the treatment of liver tumours. In this study, a biocompatible polystyrene (PS) microspheres formulation containing radioactive Samarium-153 (153Sm) was synthesized and tested. The 153Sm emits both diagnostic gamma energy and therapeutic beta radiation, renders the synthesized microspheres an ideal theranostic radioembolic agent for hepatic radioembolization. Methods: First, the 152Sm2O3 (20 – 50%, w/v) was encapsulated in PS microspheres using solid-in-oil-in-water solvent evaporation method. The 152Sm-labelled PS microspheres were then activated to 153Sm (Eβmax = 807.6 keV, half-life = 46.3 hours) via 152Sm (n,γ) 153Sm reaction in a nuclear reactor with a neutron flux of 2.0 x 1012 n.cm-2.s-1. Physicochemical characterization, gamma spectroscopy and in-vitro radiolabeling studies were carried out to study the properties and stability of the microspheres before and after neutron activation. Results: The 153Sm -labelled PS microspheres achieved a nominal activity of 4.0 GBq.g-1 after 6 hours of neutron activation. Scanning electron microscope (SEM) and particle size analysis show that the microspheres remained spherical with diameters within 15 – 60 μm after neutron activation. No long half-life radioimpurities were found in the samples as revealed by the gamma spectroscopy results. The 153Sm-labelled PS microspheres achieved radiolabeling efficiency of more than 95% in saline and blood plasma over 480 hours. Conclusion: A biocompatible 153Sm-radiolabelled PS microspheres formulation has been successfully developed. The formulation achieved desirable properties for theranostic treatment of liver tumours. The formulation is relatively cheaper, easier to be produced and more readily available.
Thirty six clinical isolates of Cryptococcus neoformans were tested for their susceptibility to 5-fluorocytosine and amphotericin B by the determination of minimum inhibitory concentrations and minimum fungicidal concentrations. 22.2% of the isolates were resistant to 5-fluorocytosine and 36.1% indicated 5-fluorocytosine tolerance. All strains were sensitive to amphotericin B.
The incidence of Campylobacter jejuni in patients with and without diarrhoea was studied in Kuala Lumpur, Malaysia. C. jejuni was recovered from 3.8% and 4.3% of diarrhoeal stools of children and adults, respectively. From the patients without diarrhoea, the relative isolation rates for children and adults were 2.6% and 0%, respectively. Dual infections occurred in two children, with Salmonella and enteropathogenic Escherichia coli being the other enteric pathogen in each case. Cary-Blair medium was found to be an effective transport medium in recovering C. jejuni. Campylobacter enteritis occurred in patients of various age groups, indicating that this organism should be sought routinely by diagnostic laboratories in faecal specimens from patients with diarrhoea.
Over a 12 months period, out of 25,411 livebirths, 155 neonates (6.1 per 1000 livebirths) had proven septicemia by blood culture. The mortality rate was 26.5%. Septicemia was more common among the very low birthweight and preterm neonates of gestation of 30 weeks or less. 45.8% of the septicemia occurred during the first 48 hours of life. Staphylococcus epidermidis was the most common causative organism. However, mortality was highest among neonates who acquired multiresistant nosocomial infection during the later part of neonatal life.
Six independent isolates of Klebsiella from hospital environmental sources in Malaysia were found to be resistant to at least ampicillin, carbenicillin, cefoperazone, chloramphenicol, gentamicin and tetracycline. On the basis of their antibiograms, they were divided into four antibiogroups. They transferred all or part of their multiple antibiotic resistance traits to E. coli by conjugation. The results suggest that these Klebsiella strains harbour self-transmissible R plasmids. The significance of these findings are discussed.
A 12-month study was carried out on the molecular epidemiology of rotavirus in urban and suburban Malaysian children. Analysis of faecal samples from 973 hospitalized diarrhoeic children by polyacrylamide gel electrophoresis detected 268 rotaviruses (28%). All isolates were group A rotaviruses, which produced 22 electropherotypes: 16 (91.5%) with long RNA migration patterns and 6 (8.5%) with short patterns. One of the long-pattern electropherotypes was the predominant strain (71.1% of the total electropherotypes) isolated during this study. Although 3 other strains were detected sporadically over the study period, 16 others were present only during the first 7 months and 2 others were confined to the last 5 months. Long- and short-pattern electropherotypes were found to co-circulate extensively. There was a significant association of short-pattern electropherotypes with infection in older children. In addition, the prevalence of vomiting and mean duration of diarrhoea were significantly associated with different electropherotypes.
Stool specimens from 334 infants and young children hospitalized with diarrhea in the General Hospital, Kuala Lumpur, Malaysia between August and November, 1987 were analyzed for the presence of rotavirus double-stranded (ds) RNA by polyacrylamide gel electrophoresis. Of the 334 specimens analyzed, 32 (9.6%) were positive for rotavirus RNA. One specimen (designated G147) exhibited a ds RNA electropherotype profile characteristic of Group C rotavirus and was selected for further characterization. In Northern blot hybridization studies, the gene 5 segment of strain G147 hybridized with a cDNA probe generated from the cloned gene 5 (which encodes the VP6 inner capsid protein that is group specific) of porcine Group C rotavirus strain Cowden, confirming the classification of strain G147 in Group C. The association of Group C rotavirus with diarrheal illness in Malaysia is consistent with earlier studies that suggest a global distribution of this virus and supports the need for additional epidemiologic studies.
Between August 1990 to November 1991, 905 of 2583 (35.4%) isolates of Staphylococcus aureus were found to be methicillin-resistant in a general hospital in Malaysia. A detailed study of 539 of these isolates showed a high prevalence of methicillin resistant Staphylococcus aureus (MRSA) in the surgical/orthopaedic wards, paediatric wards and the special care unit. The yield of MRSA was highest from wounds/ulcers/skin swabs accounting for 64.2 per cent followed by 6.9 per cent in blood cultures. Vancomycin remains the drug of choice with no resistance detected. The resistance to ciprofloxacin was 6.7 per cent, rifampicin 4.5 per cent and fusidic acid 2.0 per cent. Most isolates were resistant to aminoglycosides. In view of the high prevalence of MRSA in this hospital, the authorities must introduce more effective measures to control its spread as a nosocomial pathogen. Otherwise it may seriously disrupt the efficient delivery of health care services in the country.
Tatumella ptyseos, the type species for the genus Tatumella, is a newly established member of the Family Enterobacteriaceae. It is a Gram-negative, oxidase negative, fermentative rod that grows on Mac Conkey agar. This first isolate was obtained from the blood culture of a neonate having neonatal jaundice with presumed sepsis. The organism was in vitro sensitive to Gentamicin, Chloramphenicol, Cotrimoxazole and Ampicillin. The patient was treated with Ampicillin and Gentamicin and recovered uneventfully.
Cryptococcosis is a known opportunistic infection in immunosuppressed hosts. We report our experience of all cases presenting to our Department between December 1975 and September 1988. Eight post-renal transplant patients and three systemic lupus erythematosus (SLE) patients were affected. All were receiving treatment with steroids, in association with either azathioprine or cyclosporin. The diagnosis of cryptococcal meningitis was initially based on a positive cerebrospinal fluid (CSF) cryptococcal antigen, by latex agglutination test, and subsequently confirmed by cultures. Common clinical presentations, in descending order of frequency, included headaches, fever, mental confusion, epilepsy and papilloedema. Meningism was not a prominent feature. CT brain scans were obtained in eight patients and one showed a focal lesion and one showed cerebral atrophy. Four patients also had an abnormal chest X-ray (CXR) and one had disseminated cryptococcosis. Amphotericin and 5-fluorocytosine were the mainstay of therapy, although ketoconazole alone was subsequently used in three selected patients with cure. Four early deaths occurred in patients with delayed diagnosis and treatment, usually in association with other severe concurrent infections. We conclude that awareness of cryptococcosis is essential in immunocompromised hosts presenting with headache with, or without, mental confusion or fever.
A patient with a solitary intracranial cryptococcoma of the occipital lobe of the brain and a concomitant granuloma of similar aetiology in the breast is reported. Despite resistance of the causative fungus to 5-fluorocytosine in vitro, the patient responded well to radical excisional surgery and therapy with 5-fluorocytosine.
Mining for medical data poses different challenges compared with mining other types of data. The wide range of imaging modalities of medical data leads to data integration and compatibility issues. The analysis of imaging modalities is further complicated by the different format and attributes used by the different imaging equipment by different vendors. Human factors such as interest of adapting data mining into diagnosis and planning process raised the difficulty of engaging the users into the development of a practical and useful data miner. Requirement engineering technique prototyping further enhanced the engagement of users towards the data-miner. Data from different equipment and different vendors are also merged for efficient data analysis and subsequently charting and reporting. We have also successfully engaged the medical doctors into believing the data miner's capability after they reviewed and walkthrough the prototype.
A survey was conducted to determine the rate, outcome, and culture and sensitivity patterns of bacteraemic infections in a large Neonatal Intensive Care Unit (NICU). Over a nine-month period, 136 episodes of infection occurred in 132 (6.9%) out of 1926 admissions. Early onset infection accounted for 35 episodes (25.7%) and was associated with a higher mortality rate compared to late onset infection (45.7% vs 23.8%, p < 0.02). Very low birthweight (VLBW) infants had significantly higher rates of infection (19.4% vs 5.3%, p < 0.001) and mortality (45.2% vs 23.3%, p < 0.02) compared to bigger babies. Gram negative bacilli accounted for 25 early and 90 late isolates while gram positive organisms accounted for 10 early and 16 late isolates. The two main organisms (Acinetobacter and Klebsiella) showed a 69.0 to 85.3% resistance to aminoglycosides and 3rd generation cephalosporins. Ten of 13 isolates of Staphylococcus epidermidis and 3 of 4 Staphylococcus aureus were methicillin resistant. Multiply resistant infections were a major problem in this NICU and efforts to eradicate them needed to be intensified.
A 1 year longitudinal study of 156 Malaysian children from urban and suburban areas in the Klang Valley revealed that the incidence rate of diarrhoea was 23.6 per 100 person-year with abnormal faeces reported on 0.26% of the total days of observation. Diarrhoea cases were detected in children from all socioeconomic classes. Rotavirus was isolated from 12% of the diarrheic children and asymptomatic rotavirus infection occurred in 3.2% of the children. All rotaviruses isolated were group A rotaviruses with long electrophoretypic pattern.