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Salmon farming is the main economic activity in the fjords area of Southern Chile. This activity requires the use of antibiotics, such as oxytetracycline, for the control and prevention of diseases, which have a negative impact on the environment. We analyzed the abilities of endemic marine fungi to biodegrade oxytetracycline, an antibiotic used extensively in fish farming. We isolated marine fungi strains from sediment samples obtained from an area of fish farming activity. The five isolated strains showed an activity on oxytetracycline and were identified as Trichoderma harzianum, Trichoderma deliquescens, Penicillium crustosum, Rhodotorula mucilaginosa, and Talaromyces atroroseus by a scanning electron microscopy and characterized by molecular techniques. Results showed significant degradation in the concentration of oxytetracycline at the first 2 days of treatment for all strains analyzed. At 21 days of treatment, the concentration of oxytetracycline was decreased 92 % by T. harzianum, 85 % by T. deliquescens, 83 % by P. crustosum, 73 % by R. mucilaginosa, and 72 % by T. atroroseus, all of which were significantly higher than the controls. Given these results, we propose that fungal strains isolated from marine sediments may be useful tools for biodegradation of antibiotics, such as oxytetracycline, in the salmon industry.

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We examined the relationship between venue stability and consistent condom use (CCU) among female sex workers who inject drugs (FSW-IDUs; n = 584) and were enrolled in a behavioural intervention in two Mexico-USA border cities. Using a generalized estimating equation approach stratified by client type and city, we found venue stability affected CCU. In Tijuana, operating primarily indoors was significantly associated with a four-fold increase in the odds of CCU among regular clients (odds ratio [OR]: 3.77, 95% confidence interval [CI]: 1.44, 9.89), and a seven-fold increase among casual clients (OR: 7.18, 95% CI: 2.32, 22.21), relative to FSW-IDUs spending equal time between indoor and outdoor sex work venues. In Ciudad Juarez, the trajectory of CCU increased over time and was highest among those operating primarily indoors. Results from this analysis highlight the importance of considering local mobility, including venue type and venue stability, as these characteristics jointly influence HIV risk behaviours.

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The study on the toxicity of chitosan diethyl phosphate (ChDP), a controlled release insecticide, on the activities of butyrylcholinesterase (BuChE) and acetylcholinesterase (AChE) in rainbow trout exposed to this pesticide was carried out. It was found that ChDP reduced BuChE activity in O. mykiss by a factor of eight at 6 days, with high fluctuation to the end of the exposition time at 12 days. The in vitro analysis of brain AChE treated with ChDP and Phenamiphos showed that it was competitively inhibited by both organophosphates. The values obtained for Km and Vmax for the AChE-ChDP (Km: 21.23 microM; Vmax: 43.10 micromol/min/g) and AChE-Phenamiphos (Km: 38.62 microM; Vmax: 38.91 micromol/min/g) systems were relatively low compared to values of the AChE (control) system (Km: 62.99 microM; Vmax: 63.29 micromol/min/g). Results reported in this study confirmed that chitosan diethyl phosphate performs similarly to organophosphate pesticides, producing inhibition in cholinesterases in rainbow trout.

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BACKGROUND: Although Latinos constitute the largest and fastest growing minority group in the United States, little is known about the prevalence of renal disease among different Latino subgroups. METHODS: We used data from the Hispanic Health and Nutrition Examination Survey (HHANES) to compare serum creatinine measurements among Mexican Americans, mainland Puerto Ricans, and Cuban Americans. We compared estimated creatinine clearance across Latino subgroups adjusted for demographic, clinical, and socioeconomic characteristics (including known predictors of chronic kidney disease) using survey logistic regression analysis. RESULTS: Cuban Americans had higher mean serum creatinine levels than the other groups across both gender and age categories. In multivariable analysis, Puerto Ricans [odds ratio (OR) 1.74, 95% confidence interval (CI) 1.16 to 2.60] and Cuban Americans (OR 4.59, CI 2.53 to 8.31) were more likely than the referent category of Mexican Americans to have an estimated creatinine clearance < 60 mL/min/1.73 m2. CONCLUSION: Serum creatinine levels differ substantially among Latino subgroups, suggesting national origin needs to be taken into consideration in studies of renal disease in Latinos. In addition, our findings highlight the need for more contemporary studies directly comparing both incidence rates of end-stage renal disease and measured renal function among Latino subgroups, perhaps leading to subgroup-specific prediction equations.

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In preliminary communications, we reported the diastereoselective synthesis of cularine and sarcocapnine via the intramolecular ring closure of nitrenium and oxenium ions, a new highly diastereoselective reductive methylation with (+)-8-phenylmenthyl chloroacetate followed by reduction with sodium borohydride, and a facile entry to the isoquinoline precursors by aza-Wittig electrocyclic ring closure. We now report the full details of the syntheses of (+)-O-demethylcularine, (+)-cularine, (+)-sarcocapnidine, (+)-sarcocapnine, and (+)-crassifoline and describe different methods of synthesis of their precursors.

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We used pregnant sheep and their fetuses as well as newborn lambs (with and without severe respiratory distress due to prematurity) to study the differences in plasma clearance rate, production rate, and circulating concentrations of immunoreactive PGE2. Fetal PGE2 concentrations were significantly higher than simultaneous maternal concentrations. After delivery by cesarean section, all newborn animals were paralyzed and mechanically ventilated. The PGE2 concentrations fell in those lambs that required only minimal ventilatory support (FIO2 < 0.25) and were similar to maternal concentrations by two to three hours. Newborn lambs that developed severe respiratory distress (FIO2 < 0.55) continued to have concentrations that were even greater than fetal concentrations. The elevated PGE2 concentrations in severely distressed lambs were due not only to a decreased plasma clearance rate but also to an increased production rate of PGE2. Since PGE2 appears to maintain the patency of the ductus arteriosus in the fetus and preterm neonate, we examined the patency of the ductus arteriosus in 3-hour-old newborn lambs by radioactive microsphere injections. The ductus was more widely patent in lambs with higher concentrations of PGE2. The increased circulating concentrations of PGE2 in newborn lambs with severe respiratory distress may contribute to the pathogenesis of patent ductus arteriosus by exerting an additional vasodilatory effect on the vessel.

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Endogenous prostaglandins inhibit the ability of the ductus arteriosus to contract in response to oxygen. We studied the effects of endogenous prostaglandins and indomethacin (an inhibitor of endogenous prostaglandin production) on isometric contraction of isolated rings of lamb ductus arteriosus from animals of different gestational ages (98 to 103 days and 136 to 147 days; term is 150 days). Rings from animals at about 100 days' gestation have a significantly larger indomethacin-induced contraction than rings from animals near term. The lamb ductus arteriosus forms two prostaglandins that relax the vessel: postaglandin E2 and prostacyclin. PGI2 was three orders of magnitude less potent than PGE2. Rings from the younger animals were significantly more sensitive to the relaxing action of PGE2 and PGI2 than were rings from animals near term. This increased sensitivity of immature animals to endogenous prostaglandins is consistent with the more potent effect of indomethacin on rings from immature animals. These observations are also consistent with the findings that preterm infants have an increased incidence of patent ductus arteriosus and that indomethacin can constrict the ductus arteriosus in preterm infants.

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Chronic pulmonary arterial hypertension was produced in six fetal lambs. In four (126 to 139 days' gestation) unilateral fetal renal artery constriction caused systemic arterial mean blood pressure elevations. In another fetus, constriction of the umbilical artery caused a systemic mean blood pressure elevation; in the sixth, partial occlusion of the ductus arteriosus caused isolated pulmonary arterial hypertension. The right lung of each fetus was perfused with fixative at the in vivo mean arterial pressure and the amount of smooth muscle in the fifth generation (resistance) vessels analyzed using the medial width/external diameter ratio. There was a significant increase in the medial width/external diameter ratio in the six experimental animals as compared to that in six normal fetuses. In separate fetuses the increased ratios were due to a decreased external diameter, increased smooth muscle, or both these factors. The total number of resistance vessels was counted in the right lung of each fetus and no significant difference from normal was observed. We postulate that either fetal systemic hypertension or constriction of the ductus arteriosus causes fetal pulmonary hypertension in utero and that this produces increased smooth muscle development in pulmonary arterial resistance vessels; this may be a pathogenic mechanism for the syndrome of persistent pulmonary hypertension of the newborn infant.

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