The combined epithelial odontogenic tumour represents a hybrid lesion comprising primarily areas of adenomatoid odontogenic tumour intermixed with foci of calcifying epithelial odontogenic tumour. Five such cases retrieved from the files of the Division of Stomatology, Institute for Medical Research, Kuala Lumpur, and four others from the existing literature were analysed. A mean age of 18.8 years, a female preponderance (66.7%) with a male to female ratio of 1:2 and predilection for the mandible (55.6%) were observed. All cases were treated by conservative surgery and the lack of recurrence confirmed the innocuous nature of this lesion.
This report details a case of mandibular peripheral ameloblastoma having a clear cell component. The latter consisted of ovoid cells with vacuolated or clear cytoplasm and vesicular or pyknotic nuclei that may be disposed as discrete clusters or show direct transition from typical acanthomatous areas. Comparison of this lesion with other odontogenic and nonodontogenic tumors that contain clear cells is discussed in the context of the differential diagnosis.
Mucoepidermoid tumours of the minor salivary glands of the tongue are rarely encountered. A case of a high-grade malignant type is reported here. Merits of subdivision of the mucoepidermoid tumour on the basis of its malignant potential are outlined, and variations of histological presentation of the present tumour at its primary and nodal sites are discussed.
We investigated microwave-stimulated fixation of tissues for transmission electron microscopy using a domestic microwave oven operating at a frequency of 2.45 GHz with an output power of 500W. Microwave-stimulated fixation, in 4% glutaraldehyde, of fresh rat kidney, liver, heart and brain tissues was compared to conventional fixation. Human renal biopsies were similarly studied. Electron microscopy showed excellent ultrastructural preservation comparable to that obtained by conventional fixation. The optimal temperature range for microwave-stimulated fixation was found to lie between 50 degrees C and 55 degrees C. Our results indicate that microwave-stimulated fixation is a rapid and reproducible technique and can be effectively applied to routine diagnostic pathology.
A case is described of ameloblastoma of maxilla presenting with numerous calcified keratin pearls. The significance of cellular variation in relation to the behavioural potential of the ameloblastoma in general is briefly discussed.
The morphology, incidence and distribution of hyaline cells in ten cases each of pleomorphic adenoma, adenoid cystic carcinoma, adenocarcinoma and mucoepidermoid tumour were studied by conventional light microscopy. Results showed that the hyaline cells were identified in 60% of pleomorphic adenoma and in 20% of mucoepidermoid tumours, but were absent in adenoid cystic carcinoma and adenocarcinoma. Relative area estimation of hyaline cells in pleomorphic adenomas showed that this may range from 2.2% to 30.4% of the total tumour area. The usefulness of the hyaline cell as a diagnostic criteria in distinguishing between some of the salivary gland tumours was also discussed.
Comparative surgical audit to monitor quality of care should be performed with a risk-adjusted scoring system rather than using crude morbidity and mortality rates. A validated and widely applied risk adjusted scoring system, P-POSSUM (Portsmouth-Physiological and Operative Severity Score for the enUmeration of Mortality) methodology, was applied to a prospective series of predominantly general surgical patients at the Sarawak General Hospital, Kuching over a six months period. The patients were grouped into four risk groups. The observed mortality rates were not significantly different from predicted rates, showing that the quality of surgical care was at par with typical western series. The simplicity and advantages of this scoring system over other auditing tools are discussed. The P-POSSUM methodology could form the basis of local comparative surgical audit for assessment and maintenance of quality care.
BACKGROUND: The Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (POSSUM) is an objective and appropriate scoring system for risk-adjusted comparative general surgical audit. This score was devised in the UK and has been used widely, but application of POSSUM to centres outside the UK has been limited, especially in developing countries. This prospective study validated its application in a surgical practice with a different population and level of resources.
METHODS: All general surgical patients who were operated on under regional or general anaesthesia as inpatients over a 4-month period at Sarawak General Hospital in 1999 were entered into the study. All data (12 physiological and six operative factors) were analysed for mortality only with the POSSUM equation and the modified Portsmouth POSSUM (P-POSSUM) equation. Comparisons were made between predicted and observed mortality rates according to four groups of risk: 0-4, 5-14, 15-49 and 50 per cent or more using the 'linear' method of analysis.
RESULTS: There were 605 patients who satisfied the criteria for the study. Some 56.7 per cent of patients were in the lowest risk group. The POSSUM predictor equation significantly overestimated the mortality in this group, by a factor of 9.3. The overall observed mortality rate was 6.1 per cent and, again, the POSSUM predictor equation overestimated it at 10.5 per cent (P < 0.01). In contrast, the observed and predicted mortality rates for all risk groups, including the predicted overall mortality rate of 4.8 per cent, were comparable when the P-POSSUM predictor equation was used.
CONCLUSION: The POSSUM scoring system with the modified P-POSSUM predictor equation for mortality was applicable in Malaysia, a developing country, for risk-adjusted surgical audit. This scoring system may serve as a useful comparative audit tool for surgical practice in many geographical locations.
Loop diuretics remain a fundamental pharmacological therapy to remove excess fluid and improve symptom control in acute decompensated heart failure. Several recent randomised controlled trials have examined the clinical benefit of continuous vs. bolus furosemide in acute decompensated heart failure, but have reported conflicting findings. The aim of this review was to compare the effects of continuous and bolus furosemide with regard to mortality, length of hospital stay and its efficacy profile in acute decompensated heart failure. All parallel-arm randomised controlled trials from MEDLINE, EMBASE, PubMed and the Cochrane Database of Systematic Reviews from inception until May 2017 were included. Cross-over randomised controlled trials, observational studies, case reports, case series and non-systematic reviews that involved children were excluded. Eight trials (n = 669) were eligible for inclusion. There was no difference between furosemide continuous infusion and bolus administration for all-cause mortality (four studies; n = 491; I2 = 0%; OR 1.65; 95%CI 0.93-2.91; p = 0.08) or duration of hospitalisation (six studies; n = 576; I2 = 71%; mean difference 0.27; 95%CI -1.35 to 1.89 days; p = 0.74). Continuous infusion of intravenous furosemide was associated with increased weight reduction (five studies; n = 516; I2 = 0%; mean difference 0.70; 95%CI 0.12-1.28 kg; p = 0.02); increased total urine output in 24 h (four studies; n = 390; I2 = 33%; mean difference 461.5; 95%CI 133.7-789.4 ml; p < 0.01); and reduced brain natriuretic peptide (two studies; n = 390; I2 = 0%; mean difference 399.5; 95%CI 152.7-646.3 ng.l-1 ; p < 0.01), compared with the bolus group. There was no difference in the incidence of raised creatinine and hypokalaemia between the two groups. In summary, there was no difference between continuous infusion and bolus of furosemide for all-cause mortality, length of hospital stay and electrolyte disturbance, but continuous infusion was superior to bolus administration with regard to diuretic effect and reduction in brain natriuretic peptide.
It has been observed previously that the physical behaviors of Schmidt number (Sc) and Prandtl number (Pr) of an energy-conserving dissipative particle dynamics (eDPD) fluid can be reproduced by the temperature-dependent weight function appearing in the dissipative force term. In this paper, we proposed a simple and systematic method to develop the temperature-dependent weight function in order to better reproduce the physical fluid properties. The method was then used to study a variety of phase-change problems involving solidification. The concept of the "mushy" eDPD particle was introduced in order to better capture the temperature profile in the vicinity of the solid-liquid interface, particularly for the case involving high thermal conductivity ratio. Meanwhile, a way to implement the constant temperature boundary condition at the wall was presented. The numerical solutions of one- and two-dimensional solidification problems were then compared with the analytical solutions and/or experimental results and the agreements were promising.
A survey was conducted in several countries in the Far East in an attempt to determine the practice of obstetric analgesia and anaesthesia there. Survey forms were sent to a total of 11 countries but in the end responses from only four countries were able to provide useful information. Responses from Singapore, Hong Kong, Taiwan and Malaysia covered between 44.9% (Singapore) and 24.6% (Malaysia) of their countries' total deliveries in 1997 and were thought to be adequate to give an impression of the obstetric analgesia and anaesthesia services in their respective countries, although this would not necessarily be completely accurate. From our survey, we found that the availability of regional analgesia for labour paralleled the economic status of the country and that a significant number of caesarean sections are conducted under regional anaesthesia, mainly spinals.
In part two of "Preparing effective illustrations", the other three categories, viz. photographs, radiological images and diagrams, are discussed. Illustrations provide visual information to supplement the results in a scientific paper, and create a visual impact that can improve the readability of a paper. This article provides some basic guidelines to assist authors in preparing effective photographs, radiological images and diagrams.
Illustrations (also known as figures) are visual representations of the results obtained from a scientific study. Graphs are a common type of illustration that are often used in scientific papers to present information clearly and effectively, as well as to demonstrate relationships between variables in the data. Graphs also serve to reveal trends or patterns in the data. This article provides some basic guidelines to assist authors in preparing effective graphs for their papers.
The discussion section comprises the last component in the IMRAD system. The purpose of this section is to provide the interpretation of the results obtained, explain the implications of the findings, state study limitations and make suggestions for future research. This is a critical part of the scientific paper, as it places the particular study within the broader context of how the research contributes to improving diagnosis, treatment or patient care.
A pilot study to determine the seroprevalence of anti-HCV among children from Kuala Lumpur, Malaysia, was conducted using microparticle enzyme immunoassay. Serum samples were obtained randomly from children, aged between one to 16 years of age, admitted to the paediatric unit of University of Malaya Medical Centre, Kuala Lumpur for various medical reasons. Of the 179 samples assayed, only one was positive, giving the prevalence rate of 0.6%. It is reasonable to conclude that the seroprevalence of anti-HCV among children from Kuala Lumpur is low, less than 1%.
After submission and acceptance of a scientific paper by a journal, the final stages in the publishing process are copy-editing and proofreading. The primary purpose of this step is to ensure accurate and quality production of scientific papers. Authors are responsible for checking their proofs properly and in detail, ensuring that everything is correct as this is their last chance to make any changes before their work is set in print forever.