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51.
Chalinulasterol (1) a new chlorinated sterol disulfate was isolated from the Caribbean sponge Chalinula molitba. Its structure was elucidated using mass spectrometry and NMR experiments. The possible role of chalinulasterol as modulator of the PXR nuclear receptor was investigated but, in spite of the close structural relationship with the PXR agonist solomonsterol A (2), it showed no activity. The structural requirements for the PXR nuclear receptor activity were discussed.  相似文献   
52.
Land-based aquaculture facilities often utilize additional bicarbonate sources such as commercial sea salts that are designed to boost alkalinity in order to buffer seawater against reductions in pH. Despite these preventative measures, many facilities are likely to face occasional reductions in pH and corresponding reductions in carbonate saturation states due to the accumulation of metabolic waste products. We investigated the impact of reduced carbonate saturation states (ΩCa, ΩAr) on embryonic developmental rates, larval developmental rates, and echinoplutei skeletal morphometrics in the common edible sea urchin Lytechinus variegatus under high alkalinity conditions. Commercial artificial seawater was bubbled with a mixture of air and CO2 gas to reduce the carbonate saturation state. Rates of embryonic and larval development were significantly delayed in both the low and extreme low carbonate saturation state groups relative to the control at a given time. Although symmetry of overall skeletal body lengths was not affected, allometric relationships were significantly different between treatment groups. Larvae reared under ambient conditions had significantly greater postoral arm and overall body lengths relative to body lengths than larvae grown under extreme low carbonate saturation state conditions, indicating that extreme changes in the carbonate system affected not only developmental rates but also larval skeletal shape. Reduced rates of embryonic development and delayed and altered larval skeletal growth are likely to negatively impact larval culturing of L. variegatus in land-based, intensive culture situations where calcite and aragonite saturation states are lowered by the accumulation of metabolic waste products.  相似文献   
53.
River Gomti, a tributary of river Ganga in northern India, is being polluted due to indiscriminate disposal of domestic sewage and industrial wastes that contain genotoxic chemicals. The study was conducted to evaluate the genotoxic potential of polluted water of river Gomti in two fish species, namely Channa punctatus and Mystus vittatus. The fishes were exposed in situ in nylon cages to the polluted water of river Gomti fixed near a distillery outlet located in Lucknow. The induction of DNA damage and micronuclei were determined in blood erythrocytes using comet assay and micronucleus test, respectively. The induction in micronuclei frequencies and DNA damage were found to be significantly elevated (p?<?0.01) in exposed specimens after 3?days post-exposure as compared to the control, i.e. from laboratory-acclimatized fish specimens. The comparison of DNA damage between the two species indicated that C. punctatus is more sensitive to aquatic pollutants. Thus, this fish could be used as a bio-indicator of genotoxicity for bio-monitoring of water bodies. The results further revealed that the river Gomti is being contaminated with potential genotoxic and mutagenic chemicals produced from industrial and domestic activities; therefore, immediate measures are needed to reduce the inflow of pollutants in the river.  相似文献   
54.
Experiments were conducted to evaluate different prophylactic methods to control the bacterial load in brine shrimp, Artemia, hatching. The first experiment evaluated three treatments to control Vibrio spp. during the Artemia hatching: microalgae (Chaetoceros calcitrans), probiotic (Bacillus spp.), and antibiotic (Florfenicol). In the second experiment, Artemia metanauplius were enriched in distinct treatments with C. calcitrans, probiotic, and emulsion rich in docosahexaenoic and eicosapentaenoic fatty acids. Enriched Artemia metanauplius and nauplii (control) were offered to white shrimp, Litopenaeus vannamei, postlarvae (PL7–PL19). Presumptive Vibrio were quantified in Artemia, PL, and rearing water. Microalgae and probiotic were effective to control Vibrio spp. in Artemia nauplii. The enrichment process increased the Artemia bacterial load but did not affect Vibrio load in L. vannamei.  相似文献   
55.
Seven antimycotic drugs (econazole, enilconazole, fluconazole, griseofulvin, itraconazole, ketoconazole, and miconazole) were tested against 36 dermatophyte strains (19 M. canis, 7 T. mentagrophytes, 5 M. gypseum, 2 M. cookei, 1 T. rubrum, 1 T. ajelloi, and 1 T. terrestre) isolated from animals, humans, and the environment. Two in vitro methods were compared: a micro-dilution test based on the CLSI M38-A method, and a disk-diffusion test. Fluconazole was not effective in vitro against the dermatophytes. Econazole and enilconazole were the most effective. Thirteen strains were griseofulvin-resistant. The correlation between the two methods was statistically significant for enilconazole, griseofulvin, itraconazole, and miconazole.  相似文献   
56.
The effects of the essential oil of Eucalyptus tereticornis (EOET), especially the effects of its constituents α- and β-pinene, were studied on rat trachea in vitro. In tracheal rings, EOET, α- or β-pinene potentiated the contractions induced by acetylcholine (ACh). Contractions induced by K+ (60 mM) were also potentiated by α- and β-pinene, but were reduced by EOET. Our findings show that EOET has myorelaxant effects on rat airways, but potentiates ACh-induced contractions. Monoterpenes α- and β-pinene are involved in its potentiating actions, but are not responsible for its myorelaxant effects. A putative inhibition of the acetylcholinesterase enzyme is involved.  相似文献   
57.
58.
Canine leishmaniasis during pregnancy is rarely reported, even in countries where the infection in dogs is endemic. The authors report a case of a 4 yr old bitch with leishmaniasis treated with meglumine antimoniate during pregnancy. The pregnancy and delivery were normal and the bitch presented improvement of the infection during treatment. Three puppies died within 2 days of birth and tested negative via real-time PCR for L. infantum. The two surviving puppies were followed clinically, serologically, and by real-time PCR until 1 yr of age with no evidence of congenital leishmaniasis. L. infantum DNA was detected with real-time PCR analysis of uterine tissue from the bitch at the time of ovariohysterectomy. PCR analysis was performed after an ovariohysterectomy of the bitch that was performed two months after parturition. Meglumine antimoniate use in the pregnant bitch may have prevented vertical transmission of leishmaniasis.  相似文献   
59.
The objective of this paper was to study the changes of some cytokines and neuroendocrine hormones in vaccinated and unvaccinated pigs that were naturally infected by a PRRSV-1 (porcine reproductive and respiratory syndrome virus) heterologous field strain. We analyzed gene expression of pro-inflammatory (TNF-α, IL-1β, MCP-1, IL-6), pro-immune (IFN-γ) and anti-inflammatory cytokines (IL-10) in PBMC, as well as hormonal (GH and cortisol) levels in blood samples of pigs obtained in a field trial previously reported [Martelli P, Gozio S, Ferrari L, Rosina S, De Angelis E, Quintavalla C, et al. Efficacy of a modified-live porcine reproductive and respiratory syndrome virus (PRRSV) vaccine in pigs naturally exposed to a heterologous European (Italian cluster) field strain: clinical protection and cell-mediated immunity. Vaccine 2009;27:3788-99]. All vaccinated pigs showed an increase in pro-inflammatory and pro-immune cytokine gene expression with respect to controls and a prompt increase in GH that could be consistently associated with pro-inflammatory cytokines in sustaining innate immunity; moreover, the higher levels of cortisol indicates the activation of the hypothalamus-pituitary-adrenal (HPA) axis response. In contrast, unvaccinated pigs showed down-regulation of the cortisol and GH responses, and the pro-inflammatory and pro-immune cytokines remained at a basal or low level, with an increase of TNF-α and IL-6 in association with a higher level of IL-10 in the late phase of natural infection. The associated trends of pro-inflammatory and anti-inflammatory cytokines together with the cortisol level demonstrate that a previous vaccination promotes an early immune responsiveness in pigs and a more efficient control of inflammation in the late phase of infection with a heterologous PRRSV isolate; both events could sustain clinical protection.  相似文献   
60.
A meta-analysis was carried out in order to study the effects of endoparasites on the performance of growing pigs. Criteria that should be considered for the publication selection were: (1) the health challenge caused by parasites; (2) pig in growing phase; (3) presentation of the nutritional composition of the diets and (4) animal performance. Meta-analysis followed three sequential analysis: graphical, correlation and variance-covariance. The group that were infected with parasites had an average daily feed intake 5% lower than that the control group (2044 vs. 2147 g d(-1); P<0.001), their average daily weight gain was also 31% lower (665 vs. 987 g d(-1); P<0.001) and their feed conversion ratio was 17% superior than that of the control group (3.07 vs. 2.62; P<0.001). The variance decomposition demonstrated that 59% of the reduction in weight gain was explained by the reduction in their feed intake, as well as a 6% reduction being due to parasites.  相似文献   
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