Legislation concerning the safety assessment and labelling of foodstuffs has been implemented in many countries. Consequential to a number of cases of food adulteration reported globally, a fast and reliable detection method for the food traceability is required in ensuring effective implementation of food legislation in a country. In this study, PCR-RFLP technique based on cyt b gene has been tested for its suitability for these purposes. This method combines the use of a pair of universal primer that amplifies a 359 bp fragment on the cyt b gene from meat muscle DNA and restriction enzyme analysis. Analysis of experimental beef frankfurter, minced beef, pork frankfurter and pork cocktail samples demonstrated the suitability of the assay for the detection of the beef (Bos taurus) and pork (Sus scrofa), but not applicable for some processed food, particularly detection of mackerel (Rasterelliger brachysoma), sardine (Saedinella Fimbriata) and tuna (Thunnus tonggol) origin in canned food. Commercial frauds through species mislabelling or misdescribed were not detected. The assay is demonstrated applicable for routine analysis of meat traceability of foodstuffs and legislation purposes, if sufficient availability of detectable mtDNA in the foodstuffs is ensured.
Conventional argon laser causes transient thickening of retinal nerve fibre layer (RNFL). The effect of pattern scanning laser (PASCAL) has not been well described. We compared the immediate changes in peripapillary RNFL thickness post-panretinal photocoagulation between conventional argon lasers and PASCAL in patients with diabetic retinopathy changes. A total of 32 subjects were recruited. There were 16 patients in the argon group and 16 patients in PASCAL group. Diabetic patients were recruited from Ophthalmology Clinic, Universiti Kebangsaan Malaysia Medical Centre (UKMMC). Complete eye examinations and fundus photographs were performed at baseline prior to laser treatment, and post-laser treatment at two and four months. RNFL thickness was measured using time domain optical coherence tomography. Both groups were comparable with respect to clinical characteristics and demographics. There was no significant difference in average RNFL thickness between the two groups prior to treatment (p= 0.323). RNFL post-laser treatment for patients receiving conventional argon laser remained unchanged with no significant differences in all quadrants at any time-point (two and four months). However, for the PASCAL group, significant thickening occurred at four months for average RNFL and the inferior quadrant (p <0.05). The other quadrants similarly demonstrated increasing thickness at four months but this did not reach statistical significance. Transient RNFL thickening occurs in both conventional and PASCAL laser patients. The PASCAL laser induces a greater increase in RNFL thickness than the argon laser group. Important events, such as laser eye treatments and even type of laser used, are worthy of consideration when evaluating RNFL.
Keywords: diabetic retinopathy, optical coherence, photocoagulation, retinal ganglion cells, tomography
Study site: Ophthalmology Clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia