Eficacia y estabilidad del proceso de amonificación como tecnología de descontaminación de aflatoxina B1 en arroz (Oriza sativa) / Efficacy and stability of ammoniation process as aflatoxin B1 decontamination technology in rice

Rice, a cereal widely used in Venezuela for human and animal nutrition, is susceptible to aflatoxin contamination in the field and during storage. Therefore, the goal of this research was the evaluation of the efficacy and permanence of the ammoniation process through high pressure/high temperature (HP/HT) and atmospheric pressure/moderate temperature (AP/MT) conditions applied to rice samples artificially contaminated with aflatoxin B1. For this purpose a 2k design was drawn up considering the temperature, the rice moisture and the process time as variables. Under both sets of conditions, aflatoxin B1 concentration was reduced in a range of 90 per cent to 100 per cent. After in vitro stomach digestion simulation, toxin reversion ranged from 0 per cent to 19 per cent. In conclusion, the process efficacy and permanence were achieved through the use of high temperature and long process time for both sets of conditions (HP/HT and AP/MT), respectively.

Use of optical coherence tomography (OCT) and indirect ophthalmoscopy in the diagnosis of macular edema in diabetic patients.

OBJECTIVES: To evaluate the use of Optical Coherence Tomography (OCT) in the diagnosis of macular edema (ME) in diabetic patients in comparison to indirect ophthalmoscopy (IO) and, in addition, to study the characteristics of these patients. METHODS: 165 patients were randomly selected to join the study in 1998. Ophthalmological, clinical and laboratory examinations were performed for all these patients. RESULTS: Diabetic retinopathy was identified in 143 eyes (44.7%) and ME in 58 (18.3% of the total and 40.5% of the patients with retinopathy). 82.7% (48) of the eyes with ME could be diagnosed with OCT, against 62.0% (36) with IO. Haemoglobin A1c was the only variable that showed a significant association with ME, when compared to control (p < 0.05). Retinopathy was associated with the presence of nephropathy (p = 0.01) and neuropathy (p = 0.001), but ME was not (NS for both). 68% of patients without ME had a visual acuity of more than 50%. CONCLUSIONS: OCT is a new method that can help the evaluation of ME in diabetic patients. It can be used not only to diagnose the lesion, but also to follow up the patients during treatment. High levels of haemoglobin A1c might be associated with the presence of ME. Diabetic complications (nephropathy and neuropathy) are associated with retinopathy but not with macular edema.