The development of efficient tissue culture protocol for somatic embryo would facilitate the genetic modification breeding program. The callus induction and regeneration were studied by using different parameters i.e., auxins, cytokinins, and desiccation treatment. Scanning electron microscopy and histological analysis were performed to identify the embryogenic callus for regeneration. The callus percentage results showed that MS (Murashige and Skoog) basal medium supplemented with 3 mg/L 2, 4-D and 30g/L maltose were the optimal callus induction medium for MR220 (80%) and MR220-CL2 (95%). The morphology of the embryogenic callus was confirmed by the SEM (Scanning Electron Microscopy) (presence of extracellular matrix surface network) and later by histological analysis. Finally, MS media supplemented with 0.5 mg/L NAA (Naphthalene Acetic Acid), 2 mg/L kin, and 1 mg/L BAP were selected as the optimum regeneration media treatment while callus desiccated for 48 h was proved to produce more plantlets in MR220 (60%) and MR220-CL2 (73.33%) compared to control treatment (without desiccation). The protocol presented here showed the necessity for the inclusion of partial desiccation as an important step in the tissue culture protocol of Malaysian indica rice genotypes in order to enhance their regeneration potential.
Peripheral neuropathy is highly associated with foot complications among diabetics. This
study aimed to identify risk factors associated with the development of peripheral neuropathy in diabetic patients and their association with degree of severity of peripheral neuropathy. A cross-sectional study was conducted in follow-up clinics at the Universiti Kebangsaan Malaysia Medical Centre (UKMMC), Malaysia involving 72 diabetic patients and 19 controls. Exclusion criteria were those with amputated limbs, gross foot deformity and existing peripheral neuropathy. Controls were non diabetics who walked normally, had no history of foot problem and attended the clinic as subjects’ companion. Quantitative assessment of neuropathy was done using Semmes-Weinstein monofilament. Neuropathy Disability Score (NDS) were used to quantify severity of diabetic neuropathy. Spearman’s Rank test and Mann-Whitney test were used to determine correlation between variables and their differences. Logistic regression analysis was used to determine risk factors associated with peripheral neuropathy. The mean HbA1c among diabetics was 8.6% + 4.1, and mean NDS was 7.0 + 6.0. A total of 79.1% demonstrated various level of neuropathy with presence of callus was associated with higher NDS scores. Older age (P=0.02), body weight (P=0.03), HbA1c (P=0.005) and duration of diabetes (P <0.005) showed positive correlation with NDS. Proper foot care program for diabetics should include recognition of the callus, with special emphasis given to those with heavier weight and increasing age.
Key words: diabetes mellitus, peripheral neuropathy, Neuropathy Disability Score
(NDS), Semmes Weinstein monofilament (SWMF), callus
Study site: follow-up clinics at the Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM)
During high-temperature refining of vegetable oils, 3-monochloropropanediol (3-MCPD) esters, possible carcinogens, are formed from acylglycerol in the presence of a chlorine source. To investigate organochlorine compounds in vegetable oils as possible precursors for 3-MCPD esters, we tested crude palm, soybean, rapeseed, sunflower, corn, coconut, and olive oils for the presence of organochlorine compounds. Having found them in all vegetable oils tested, we focused subsequent study on oil palm products. Analysis of the chlorine isotope mass pattern exhibited in high-resolution mass spectrometry enabled organochlorine compound identification in crude palm oils as constituents of wax esters, fatty acid, diacylglycerols, and sphingolipids, which are produced endogenously in oil palm mesocarp throughout ripening. Analysis of thermal decomposition and changes during refining suggested that these naturally present organochlorine compounds in palm oils and perhaps in other vegetable oils are precursors of 3-MCPD esters. Enrichment and dose-response showed a linear relationship to 3-MCPD ester formation and indicated that the sphingolipid-based organochlorine compounds are the most active precursors of 3-MCPD esters.