Optimisation of topical antibacterial preparation from Malaysian kelulut honey by using xanthan gum as polymeric agent.

The study aims to formulate and optimise topical antibacterial preparation by using Malaysian kelulut honey as the active ingredient and xanthan gum as the polymeric agent. Response surface methodology was used to optimise the preparation. The acidity, honey concentration and xanthan gum concentration were the independent variables. The zone of inhibitions on S. aureus ATCC6538 and E. coli ATCC8739 were the response variables. The optimal preparation was evaluated on its physicochemical properties, viscosity, antibacterial efficacy and stability. The antibacterial efficacy of the optimal preparation was compared to the commercially antibacterial gel (MediHoney™, Comvita). The optimal preparation was formulated at pH of 3.5, honey concentration of 90% (w/v) and xanthan gum concentration of 1.5% (w/v) with the inhibition zones measured on S. aureus ATCC6538 was 16.2 mm and E. coli ATCC8739 was 15.8 mm respectively. The factors of acidity and honey concentration have significantly influenced the inhibition zone on S. aureus ATCC6538 and E. coli ATCC8739. The utilisation of xanthan gum as the polymeric agent was fit for the preparation which showed by adequate physicochemical properties and retained of the antibacterial effects. This was supported by constant viscosity and efficacy of the preparation within the six months of stability study indicating stable and reliable preparation. Xanthan gum is a potential polymeric agent due to its effective use in preparing stable preparation with effective antibacterial properties.

Ridge regression and its applications in genetic studies.

With the advancement of technology, analysis of large-scale data of gene expression is feasible and has become very popular in the era of machine learning. This paper develops an improved ridge approach for the genome regression modeling. When multicollinearity exists in the data set with outliers, we consider a robust ridge estimator, namely the rank ridge regression estimator, for parameter estimation and prediction. On the other hand, the efficiency of the rank ridge regression estimator is highly dependent on the ridge parameter. In general, it is difficult to provide a satisfactory answer about the selection for the ridge parameter. Because of the good properties of generalized cross validation (GCV) and its simplicity, we use it to choose the optimum value of the ridge parameter. The GCV function creates a balance between the precision of the estimators and the bias caused by the ridge estimation. It behaves like an improved estimator of risk and can be used when the number of explanatory variables is larger than the sample size in high-dimensional problems. Finally, some numerical illustrations are given to support our findings.

Demographic study of brain tumour in a neurosurgical department in Terengganu, Malaysia.

INTRODUCTION: Brain tumour (BT) is a tremendous burden on patients, families as well as the surrounding communities, especially the healthcare services. It can be classified into either a benign slow growing tumour (non-cancerous) and malignant tumour (cancerous). The purpose of this study was to determine the incidence and pattern of brain tumour admitted to the Neurosurgery Department in Hospital Sultanah Nurzahirah (HSNZ), Terengganu, Malaysia. METHODS: This is a retrospective study of incidence and pattern of BT admitted to the Neurosurgery Department in HSNZ. Data was collected from the yearly census of BT registered from 2013 to 2018. RESULTS: A total number of 386 new cases of primary BT were registered. The number of cases of BT was found to be lowest among children (0 to 10 years old) with only 4.4% but at peak among elderly aged between 51 to 60 years old (26.2%). As for gender, males constituted about 44.5% (n=172) whereas females accounted for 55.5% (n= 214) of the cases. In total, meningioma was found to have the highest incidence (27.2%) followed by metastases brain tumour (18.1%) and glioma (17.4%). CONCLUSIONS: This study has shown that the incidence of BT was led by meningioma which had a high prevalence among the elderly population, followed by metastasis BT and gliomas.

Haemostasis in oral surgical procedures involving patients with a ventricular assist device.

The purpose of this study was to determine whether tooth extraction for patients with ventricular assist devices (VADs) could be performed without interruption of anticoagulant and/or antiplatelet therapy and whether treatment with von Willebrand factor concentrates and desmopressin is required. The study consisted of three groups of patients undergoing oral surgery. The two experimental groups comprised patients with VADs, while the third group included cardiovascular patients without VADs who served as controls. All patients were treated intraoperatively with topical haemostatic agents (oxidized cellulose or collagen). The first group was additionally treated with fibrin glue. All 75 oral surgical procedures were performed under local anaesthesia without sedation. Three of 40 patients in the experimental groups and two of 20 patients in the control group suffered a haemorrhage, with no significant difference in the incidence of haemorrhage between the groups. The findings suggest that dental extraction can be performed without modification of oral anticoagulation or antiplatelet treatments, providing that INR is less than 3.5 on the day of the operation. It can further be hypothesized that an acquired coagulopathy in VAD patients does not influence the bleeding risk in dental extractions, and so the administration of desmopressin and/or von Willebrand factor concentrates is not required.