Biochemical characterization of acid proteases from the stomach of palometa (Pygocentrus nattereri, Kner 1858) with potential industrial application.

Pepsin is one of the major enzymes with significant importance in the food industry, biomedicines, and pharmaceutical formulations. In this work, the main objective was to biochemically characterize a pepsin-like enzymatic extract obtained from Pygocentrus nattereri, a predatory freshwater fish, focusing on their potential industrial application. The obtained extract exhibited optimal activity at 45 °C and pH 1.0-2.0. These proteases remained stable after 2 h of incubation at temperatures ranging from 0° to 45 °C and within pH range of 1.0 to 7.0. Their activity was significantly affected in presence of pepstatin A and SDS, 10 µM and 3.46 mM respectively, while EDTA and PMSF showed partial inhibitory effects. Divalent cations (Ca2+ and Mg2+) did not inhibit the proteolytic activity of the extract; in fact, it improved at a 5 mM CaCl2 concentration. As the NaCl concentration increased, the enzyme activity decreased. However, after desalination, 90 % of the activity was recovered within the tested exposure time. Besides, this extract demonstrated exceptional versatility across diverse industrial applications, including collagen extraction augmentation, IgG hydrolysis facilitation, and silver and polyester recovery from X-ray films. Our results suggest that the obtained enzymatic extract has a wide range of potential applications.

First record of clinical coccidiosis (Eimeria ovinoidalis) in adult sheep from northwestern Argentina.

Coccidiosis of sheep is an intestinal infection caused by protozoa of the genus Eimeria. An outbreak of the disease in adult sheep from Salta province, northwestern Argentina, was studied to establish its clinical, epidemiological, pathological and etiological aspects. The affected animals were part of a flock of 20 sheep brought from Formosa province about 10 days before. Most sheep (80% incidence) showed hemorrhagic diarrhea, dehydration and loss of body condition; six of them died and two that became permanently recumbent were euthanized. Three necropsied sheep showed mild mesenteric lymphadenomegaly, diffuse proliferative enteritis in the small and large intestines, and mucosal thickening. Histopathological studies exhibited diffuse proliferative enteritis and presence of structures compatible with intracellular coccidia at different stages of development. Parasitological studies (n = 12) resulted in an average of 16,636.6 (± 15,266.8) Eimeria oocysts per gram of feces (range 1680-46,400). Taxonomy of Eimeria species based on analysis of sporulated oocysts derived from 4 fecal samples (n = 100 oocyst per sample) showed, on average, a high prevalence of E. ovinoidalis (61.5%), followed by E. parva (27.2%), and lower proportions of E. crandallis (5.3%), E. ahsata (3.2%) and E. intricata (2.8%). Clinical and pathological findings confirmed the diagnosis of coccidiosis in the affected sheep; parasitological results showed that E. ovinoidalis was the main species responsible for the clinical signs. Clinical coccidiosis is considered unusual in adult sheep, but the present case shows that under favorable environmental and/or management conditions, this infection may be highly deleterious for adult sheep.

Four-year safety follow-up of the tetravalent dengue vaccine efficacy randomized controlled trials in Asia and Latin America.

OBJECTIVE: Our objective was to describe the risk of hospital admission for virologically confirmed dengue (VCD) and the risk of clinically severe hospitalized VCD occurring up to 4 years after the first dose (years 1 to 4) in three randomized clinical trials comparing tetravalent dengue vaccine with placebo. METHODS: The relative risks (RR) for hospitalized VCD from first dose to year 4 were estimated by year and age-group in individual and combined studies. RESULTS: Overall, from Year 1 to Year 4, 233 and 228 participants had at least one episode of hospitalized VCD in the vaccinated (n = 22 603) and placebo (n = 11 301) groups, respectively (RR = 0.511, 95% CI 0.42-0.62). Among these, 48 and 47 cases, respectively, were classified as clinically severe. In children aged ≥9 years, 88 and 136 participants had at least one episode of hospitalized VCD in the vaccinated (n = 17 629) and placebo (n = 8821) groups, respectively (RR = 0.324; 95% CI 0.24-0.43). In vaccinated participants aged <9 years, particularly in those aged 2-5 years, there were more hospitalized VCD cases compared with the control participants in Year 3 but not in Year 4. The overall RR in those aged <9 years for Year 1 to Year 4 was 0.786 (95% CI 0.60-1.03), with a higher protective effect in the 6-8 year olds than in the 2-5 year olds. CONCLUSIONS: The overall benefit-risk remained positive in those aged ≥9 years up to year 4, although the protective effect was lower in years 3 and 4 than in years 1 and 2.

Outcomes of vitreoretinal surgery for retinal detachment after LASIK for myopia.

PURPOSE: To report and compare outcomes of vitreoretinal surgery for repair of retinal detachment in myopic patients with and without previous laser-assisted in situ keratomileusis (LASIK). METHODS: This is a descriptive retrospective observational study with a control group for comparison that consisted of the analysis of clinical and surgical charts of patients who underwent vitreoretinal procedures for retinal detachment at the Fundación Oftalmologica Nacional between January 1995 and December 2002. The authors identified those myopic patients who had previous history of LASIK and an age- and myopia-matched control group without refractive surgery. RESULTS: The sample contains 24 myopic eyes of 22 patients with previous LASIK and 23 myopic eyes without previous LASIK in the control group, matched by age and myopia. Mean refractive error was -9.4 D before LASIK for the cases group and -11.2 for the control group. Poor preoperative best-corrected visual acuity was present in 71% of cases and 61% of controls (p=0.489). Macula off retinal detachment was found in 17 eyes in both groups. Five eyes required at least two procedures, achieving 91% (20 eyes) reattachments at the end of follow-up in each group. Final best-corrected visual acuity was better than 20/100 in 15 eyes (62.5%) in the LASIK group and 17 eyes (74 %) in the control group (p=0.659). CONCLUSIONS: Retinal detachment in patients with previous myopic LASIK has similar characteristics as in myopic patients without refractive surgery. Current vitreoretinal surgery is of good prognosis as the retina was successfully reattached in most cases in both groups.

Role of cigarette smoking as a gateway drug to alcohol use in Hispanic junior high school students.

BACKGROUND: Many studies have examined predictors of alcohol and other substance use in adolescents, but few have looked specifically at Hispanic adolescents in their junior high school years. PURPOSE: The purpose of this study was to explore the extent to which tobacco use may contribute as a gateway drug for subsequent alcohol use among Hispanic adolescents in San Diego, Calif. METHODS: A multiple regression procedure was used to test if 7th-grade to 9th-grade change in smoking status predicted 9th-grade alcohol use while controlling for a variety of other variables. RESULTS: Among the variables analyzed, increased level of smoking was the strongest predictor of subsequent 9th-grade alcohol use, followed by stronger intentions to drink, female sex, and having grades below a "C." CONCLUSION: 7th- to 9th-grade smoking change is highly predictive of subsequent alcohol use. IMPLICATIONS: The study findings suggest that preventive intervention for alcohol use among Hispanic adolescents should focus on changes in smoking status as a significant risk factor and should examine the role of acculturation and other variations that make this population different from other U.S. subgroups.