•Vaccination against S. agalactiae is likely to be profitable in tilapia farms in Brazil.•The higher the pre-vaccination mortality, the greater the financial net returns.•Should cumulative mortality ...be low, profitability of vaccination depends on better FCR.•Improvement in FCR seems to have greater impact on profitability than vaccine efficacy.•Feed and vaccine costs had minor effects on the output in all mortality scenarios.
Infection with Streptococcus agalactiae causes mortality and major economic losses in Nile tilapia (Oreochromis niloticus) farming worldwide. In Brazil, serotype strains Ia, Ib and III have been isolated in streptococcosis outbreaks, but serotype Ib is the most prevalent. Vaccination is considered an effective method to prevent economically-important diseases in aquaculture and has been associated with decreased use of antibiotics and improvements in fish survival. We developed a flexible partial-budget model to undertake an economic appraisal of vaccination against Streptococcus agalactiae in Nile tilapia farmed in net cages in large reservoirs. The model considers the benefits and costs that are likely to be associated with vaccination at the farm-level, in one production cycle. We built three epidemiological scenarios of cumulative mortality attributable to S. agalactiae (5%, 10%, and 20%, per production cycle) in a non-vaccinated farm. For each scenario, we applied a stochastic model to simulate the net return of vaccination, given a combination of values of “vaccine efficacy”, “gain in feed conversion ratio”, “feed price”, “fish market price “, and “cost of vaccine dose”. In the 20% cumulative mortality scenario, the net return would break-even (benefits ≥ costs) in at least 97.9% of interactions. Should cumulative mortality be lower than 10%, the profitability of vaccination would be more dependent on better feed conversion ratio. The inputs “feed price” and “cost of vaccine” had minor effects on the output, in all pre-vaccination mortality scenarios. Although our simulations are based on conservative values and consider uncertainty about the modeled parameters, we conclude that vaccination against S. agalactiae is likely to be profitable in Nile tilapia farms, under similar production conditions.
The presence of oxidative stress in patients with asthma is well documented; however, the role of oxidative stress in allergic rhinitis has received less attention, although it is likely to be ...similar to that observed in patients with asthma. Advanced glycation end products (AGEs) and advanced oxidation protein products (AOPPs) are compounds formed by the transformation of macromolecules, including proteins, which can serve as densitometric markers of oxidative stress and inflammation in several diseases.
The aim of this study was to investigate the role of AGEs and AOPPs as new markers of oxidative stress and inflammation in patients affected by allergic rhinitis.
AGE and AOPP levels were determined in the sera of 25 patients with allergic rhinitis and 64 healthy controls. AGEs and AOPPs were detected using spectrofluorimetry and spectrophotometry, respectively.
AGE levels in patients were significantly higher than those in controls (P < .0001). These levels were not affected by the presence of asthma. No statistically significant differences were found between AOPP levels in patients or controls (P = .38).
Formation of AGEs and AOPPs may be accelerated in immunological and respiratory disorders such as asthma. Depending on the marker evaluated, the presence or absence of oxidative stress in allergic rhinitis is controversial. To our knowledge, this is the first study showing the possible involvement of AGEs in allergic rhinitis. The different behavior observed for these 2 biomarkers is very likely due to the activation of specific related biochemical pathways (eg, the myeloperoxidase pathway) associated with the condition under study.
Exposure of pregnant Long-Evans rats to elemental mercury (Hg0) vapor resulted in a significant accumulation of Hg in tissues of neonates. Because elevated Hg in neonatal tissues may adversely affect ...growth and development, we were interested in how rapidly Hg was eliminated from neonatal tissues. Pregnant rats were exposed to 1, 2, or 4 mg $Hg^0 vapor/m^3$ or air (controls) for 2 hr/day from gestation day 6 (GD6) through GD15. Neonatal brain, liver, and kidney were analyzed for total Hg at various times between birth and postnatal day 90 (PND90). Milk was analyzed for Hg between birth and weaning (PND21). Before weaning, the Hg levels in neonatal tissues were proportional to maternal exposure concentrations and were highest in kidney followed by liver and then brain. There was no elimination of Hg between birth and weaning, indicating that neonates were exposed continuously to elevated levels of Hg during postpartum growth and development. Consumption of milk from exposed dams resulted in a slight increase in kidney Hg concentration during this period. Unexpectedly, neonatal Hg accumulation increased rapidly after weaning. Increased Hg was measured in both control and exposed neonates and was attributed to consumption of NIH-07 diet containing trace levels of Hg. By PND90, tissue Hg levels equilibrated at concentrations similar to those in unexposed adult Long-Evans rats fed the same diet. These data indicate that dietary exposure to trace amounts of Hg can result in a significantly greater accumulation of Hg in neonates than gestational exposure to high concentrations of Hg0 vapor.
New layered inorganic−organic magnesium organosilicates were prepared by a single-step template sol−gel synthesis through the reaction of magnesium ions with a synthetic homologous series of ...urea−alkoxysilanes with the general formula (CH3CH2O)3Si(CH2)3NHC(O)NH(CH2) n CH3, for n = 2, 4, and 6. The nanocomposites were characterized by elemental analysis, solid-state 29Si and 13C nuclear magnetic resonance, X-ray diffraction, and thermogravimetry. The results showed that the hybrid materials exhibit lamellar structures similar to those found in the natural inorganic silicate talc. The influence of the length of the organic group of the urea−alkoxysilane employed in the formation of these layered structures is clearly observed by 29Si NMR spectroscopy. A high degree of condensation for the hybrid synthesized with urea−alkoxysilane containing the longest alkyl chain was obtained. These materials seem to be promising as sorbents for solid-phase extraction of organic pollutant molecules, when dispersed in water, because of their highly hydrophobic character.
In the present study, the effect of potassium depletion on the expression of acid-base transporters in the collecting duct was examined. Toward this end rats were fed a potassium-free diet for 3 ...weeks. Thereafter, the expression of the basolateral chloride/bicarbonate exchangers AE1 and SLC26A7 and the apical H+-ATPase was examined by northern hybridization, immunoblot analysis and immunofluorescence labelling. The mRNA expression of AE1 increased by a robust ∼500% in the cortex and ∼70% in the outer medulla, which translated into a huge increase in AE1 protein abundance in the cortex and a moderate increase in the outer medulla in K-depletion. The mRNA expression of SLC26A7 did not change significantly but its protein abundance showed a robust increase in the outer medulla. The expression of SLC26A7 remained undetected in the cortex in K-depleted rats. The post translational increase in SLC26A7 membrane abundance in potassium depletion was recapitulated in vitro using epitope-tagged SLC26A7. H+-ATPase displayed enhanced apical plasma membrane immunoreactivity in the OMCD in K-depletion. We suggest that the up-regulation of SLC26A7 and AE1 on the basolateral membrane of A-intercalated cells in the OMCD and CCD, respectively, along with H+-ATPase on the apical membrane, contributes to enhanced bicarbonate absorption in the collecting duct in K-depletion.
•The work describes a unified framework for 3D optical measurements by active devices.•Light encoding is integrated with an LCD screen for stereo-camera calibration.•Bundle adjustment is used to ...correct the screen non-planarity.•The same light encoding approach is integrated with a projector for 3D scanning.•Results are provided with different optical setups to prove the methodology flexibility.
The use of light encoding techniques is widespread in the field of 3D surface reconstruction. This paper presents a stereo-camera calibration methodology, which integrates structured light encoding with an active digital device. The structured light encoding approach is proposed to unambiguously solve the stereo matching issue for stereo-camera setups. A sequence of vertical and horizontal binary striped patterns, combined with a checkerboard pattern, is displayed by a high-resolution LCD screen, which is used as calibration board. A bundle adjustment technique is adopted to simultaneously adjust both camera parameters and screen geometry, as part of the stereo-camera calibration process, thus taking into account the possible inaccuracies of the digital display. The same structured light approach, with small variants, is projected by a multimedia digital projector to carry out 3D surface reconstruction. The proposed methodology defines a comprehensive framework for the development of a 3D optical scanner, from calibration to 3D acquisition, which has been validated by measuring primitive surfaces and reconstructing free-form shapes with different stereo-camera setups.
Considering the novel functions for both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in the developing nervous system (reviewed in Layer and Willbold, Prog. Histochem. Cytochem., ...1995) a quantitative survey of the spatiotemporal developmental profiles of both AChE and BuChE activity in the neonatal rat brain would be extremely useful. To that end, we collected six brain regions at seven developmental time points, (postnatal day 1, 4, 7, 12, 17, 21, adult;
n≥3) and measured AChE and BuChE activity using both biochemical and histological methods. These results indicated that the developmental pattern of AChE and BuChE activity varied with respect to brain region and age: (1) the ontogeny of either AChE or BuChE specific activity in one region was not necessarily indicative of the developmental pattern of the same cholinesterase in other regions; (2) the AChE developmental profile in a given region did not necessarily predict the BuChE developmental pattern for that same region. The data were also analyzed from a different perspective, i.e., the ratio of BuChE–AChE activity, in order to determine if BuChE activity preceded AChE activity during development as has been proposed for the chick nervous system (Layer, Proc. Natl. Acad. Sci. USA, 1983). Our analysis showed that, in general, the BuChE–AChE ratio decreased as the region matured, data which parallel the pattern of development of these esterases in the chick nervous system.
Abstract Dimethyltin (DMT) is one of several organotins that are detected in domestic water supplies due to their use as plastic stabilizers for polyvinyl chloride (PVC) and chlorinated PVC (CPVC) ...products. A limited number of in vitro and in vivo studies suggest that DMT may produce developmental neurotoxicity; therefore, we initiated studies to evaluate long-term neurobehavioral changes in offspring following perinatal exposure. In the first study, female Sprague–Dawley rats were exposed via drinking water to DMT (0, 3, 15, 74 ppm) before mating and throughout gestation and lactation. Male offspring were tested for changes in: 1) preweaning learning in an associative runway task, 2) motor activity ontogeny, 3) spatial learning and retention in the Morris water maze as adults, 4) brain weight, 5) biochemical evidence of apoptosis, and 6) neuropathology. DMT toxicity was expressed as depressed maternal weight gain (74 ppm), and in the offspring, decreased brain weight (3, 74 ppm), decreased apoptosis (all concentrations), mild vacuolation in adult offspring (all concentrations), and slower learning in the water maze (15 ppm) due to altered spatial search patterns. In a second study, DMT exposure (same concentrations) occurred from gestational day 6 to weaning. Male and female offspring were tested. The high concentration again depressed maternal weight gain, decreased offspring birth weight and preweaning growth, and decreased brain weight. Increased and decreased apoptotic markers were measured, depending on age. Learning deficits were observed in the runway at postnatal day 11 (15, 74 ppm) and again in the adult offspring in the water maze (15 ppm). The results of both studies demonstrate a reproducible effect of 15 ppm perinatal DMT exposure on spatial learning. Changes in expression of apoptosis, brain weight, and the occurrence of neuropathological lesions also indicate potential neurotoxicity of DMT. These results were in contrast to earlier findings with monomethyl tin, for which only similar neuropathological lesions were observed. Thus, developmental neurotoxicity may be produced in offspring following gestational exposure to DMT in drinking water.
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