Fast protocol for extraction of DNA from Prosopis spp leaves (plant adapted to arid environment) without liquid nitrogen.

The extraction of high-quality genomic DNA from Prosopis spp for polymerase chain reaction (PCR) amplification is complicated, owing to the presence of a high percentage of secondary metabolites that bind to or co-precipitate with nucleic acids. In the present study, we report a modified sodium dodecyl sulfate/phenol protocol that eliminates the use of liquid nitrogen in the maceration process, ß-mercaptoethanol in the buffer extraction, and the ethanol precipitation step. The A260/A280 absorbance ratios of the isolated DNA were approximately 2.0 to 1.9, suggesting that the DNA fraction was pure and can be used for further PCR analysis. The DNA isolated by this protocol is of sufficient quality for molecular applications; this technique could be applied to other organisms that have similar substances that hinder DNA extraction. Finally, this proposal represents an alternative fast, cheap, and effective method for the isolation of genomic DNA from fresh leaves of Prosopis spp, even in low-technology laboratories.

Treatment of symptomatic epiblepharon with Botulinum toxin type A in patients under 2years of age. / Experiencia del uso de la toxina botulínica tipo A para el tratamiento sintomático del epiblefaron en pacientes menores de 2 años.

INTRODUCTION: Epiblepharon is a congenital eyelid malposition due to a horizontal skin fold and a redundant orbicular muscle, resulting in the inward positioning of the eyelashes. OBJECTIVE: Personal experience is presented of the non-surgical correction of symptomatic epiblepharon using a pretarsal injection of 5 IU of botulinum toxin type A (BoNT-A) into the orbicular muscle. MATERIAL AND METHODS: Patients with epiblepharon younger than 2 year were included in the study. A review was made of their clinical charts and the symptoms and signs of epiblepharon were evaluated before and after treatment with BoNT-A. RESULTS: A total of 40 patients were included (28 girls [70%]). The mean age at treatment was 11 months (range, 4-24 months). A total of 76 eyelids were treated with BoNT-A. A statistically significant improvement in symptoms, lash-corneal touch, and punctate corneal epitheliopathy were reported after the treatment with 5IU BoNT-A. The mean final follow-up was 25.5 weeks (range, 4-92 months). CONCLUSIONS: The present study provides evidence that a pretarsal BoNT-A injection is an effective and safe treatment for the correction of symptomatic epiblepharon in patients younger than 2 years of age.

Outcomes and complications after phacoemulsification in retinoblastoma patients with cataract after radiation treatment. / Facoemulsificación en pacientes con retinoblastoma y catarata por radioterapia: resultados y complicaciones.

PURPOSE: To describe the visual outcome and complications associated with phacoemulsification in patients with bilateral retinoblastoma (Rb), with lens opacification secondary to external beam radiotherapy. METHODS: A descriptive study was performed on patients with Rb, treated in Federico Gomez Children's Hospital, Mexico, from January 1997 to August 2015, with external beam radiotherapy eye salvaging. Statistical analysis was performed using Stata 10. RESULTS: A total of 15 patients were included. The mean age at phacoemulsification was 7.5 years. Mean preoperative visual acuity was 1.0LogMAR (range 0.4-1.6), and the mean postoperative visual acuity was 0.7LogMAR (range 0.1-1.6). Twelve patients had visual improvement (P<.05). The visual acuity decreased in one patient with vitreous haemorrhage and secondary glaucoma, and 2 patients with exudative maculopathy secondary to radiation. Mean follow up was 46 months and not a single patient showed tumour re-activation. CONCLUSIONS: Cataract surgery produces a statistically significant improvement in visual acuity. These patients have increased risk for eye complications in the mid- and long-term. It is important to conduct a close follow up due to reactivation of tumour.

Plasma response of children to short-term chronic beta-carotene supplementation.

Plasma concentrations of beta-carotene and retinol after supplementation of children with beta-carotene in supplements and in foods were compared in Guatemalan children. The children received 6 mg/d beta-carotene [1000 retinol equivalents (RE)] as purified supplements or as carrots for 20 d and the effects on plasma beta-carotene and retinol concentrations were assessed. Plasma concentrations of beta-carotene were increased by 0.59 +/- 0.65 and 0.60 +/- 0.67 mumol/L after supplementation with beta-carotene capsules for 10 and 20 d, respectively. Addition of cooked carrots to the diet resulted in no significant change in plasma beta-carotene. Fasting plasma retinol concentrations were 1.23 +/- 0.35 mumol/L and were not significantly changed in response to supplementation with either of the carotene treatments with retinyl palmitate (1000 RE/d) for 20 d. Possible explanations for the differences in effects of plasma concentrations between the two methods of supplementation are discussed.

Plasma response to oral beta-carotene in Guatemalan schoolchildren.

The response to oral doses of beta-carotene (0 mg, n = 10; 15 mg, n = 20; and 30 mg, n = 21) was studied in 51 Guatemalan children aged 8-15 y, with mean fasting plasma retinol concentrations of 1.72 +/- 0.38 mumol/L. Beta-carotene was delivered with a chocolate drink containing 8.4 g fat. Serial blood sampling was performed at intervals up to 48 h. Circulating retinol concentrations remained relatively constant. The maximum increases in plasma beta-carotene after the 30- and 15-mg doses for all subjects occurred at 24 h and were 0.29 and 0.23 mumol/L, respectively. Time of maximum increase for individuals varied and average maxima over the 48-h period for individuals were 0.13 and 0.26 mumol/L for the 15- and 30-mg-treatment groups, respectively. Increased plasma beta-carotene concentrations were not predicted by recent intake of dietary vitamin A, fasting plasma concentrations, or anthropometric measurements.