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131.
α-Cypermethrin (Cyp) is a synthetic insecticide used to control pests in agricultural crops and to protect human health against noxious insects; this toxic can reach aquatic systems through ground infiltration or by runoff and could affect the aquatic biota. The present study was aimed at evaluating the acute toxicity of Cyp on zebrafish (Danio rerio) exogenous feeding larvae of 10 and 20 days post-fertilization (dpf), and of sublethal concentrations on only 10-dpf larvae. Proteins, lipids, carbohydrates, glycogen concentration, and total energy contents, as well as malondialdehyde (MDA) quantification, through thiobarbituric acid reactive substances, as a lipid peroxidation biomarker, were assessed in free-feeding larvae exposed to sublethal Cyp concentrations. The LC50 for 10-dpf larvae was 1.94 µg L?1, and these were more sensitive than 20-dpf larvae (3.56 µg L?1). The amount of protein, carbohydrates, and glycogen were not significantly affected (p > 0.05), but sublethal Cyp concentrations exposure caused decrement in lipids from 9.05 to 3.74 µg larva?1, as well as a reduction in MDA and in the total energy content, which affected significantly the development of this fish. Although Cyp is considered an insecticide of reduced residual effect in the environment, the present study revealed that relatively low Cyp concentrations produced significant toxic effects on exogenous feeding fish larvae, a situation that could contribute to increase deaths during this already critical developmental stage in which high mortality is observed frequently.  相似文献   
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133.
Vibrio nigripulchritudo is considered one of the major pathogens threatening shrimp aquaculture. In this study, we developed a novel and highly specific quantitative loop-mediated isothermal amplification (Q-LAMP) assay. A set of four specific primers were designed targeting the V. nigripulchritudo intergenic spacer region. The reaction time and temperature were optimized for 60 min at 63°C. Quantitative analysis was then performed by measuring the turbidity of the reaction solution using a real-time turbidimeter, allowing for quantification of the initial DNA concentration with a sensitivity of 102 copy numbers equivalent to 2.3 colony forming units/ml or 0.3 fg/μl. The LAMP assay was able to specifically detect two representative strains of V. nigripulchritudo, whereas other Vibrio and non-Vibrio species were not amplified. A standard curve was generated for V. nigripulchritudo by plotting the threshold time (T t) versus the log of bacterial number. A high correlation coefficient (R 2 = 0.9749) was observed for the Q-LAMP reaction. In conclusion, Q-LAMP assay is a sensitive, rapid, and simple tool that can be used for the detection and quantification of V. nigripulchritudo in shrimp, thereby facilitating surveillance of vibriosis infection.  相似文献   
134.
A feeding trial was conducted to evaluate the effect of fermented soybean meal and scallop by-product blend (3:2) (FP) on the performance of juvenile red sea bream. Five isocaloric diets were prepared by replacing 0% (FP0), 15% (FP15), 30% (FP30), 45% (FP45), and 60% (FP60) fishmeal (FM) protein with FP, respectively. Triplicate groups of fish (initial mean weight 2.83 g) were fed the test diets for 45 days in a flowthrough seawater system. The results demonstrated that growth rates of fish fed FP0, FP15, and FP30 were similar, and significantly higher (P < 0.05) than those of FP45 and FP60. Nutrient utilization was significantly lower in FP60, with no differences found among the other groups. Dietary heavy-metal contents were affected by inclusion of FP, impacting on whole-body heavy-metal contents. In terms of oxidative stress, fish fed the FP30 diet were in the best condition, since this fish group showed the least oxidative-stressed condition as well as the highest tolerance against oxidation. In conclusion, the approach of utilizing this fermented mixture is promising and it could replace at least 30% FM protein in red sea bream diet without negative effects on performance, body composition or health of fish.  相似文献   
135.
136.
Climate change spurs havoc on social-ecological system. People and places vulnerable to climate change have been the focus of many discussions. However, in the forestry sector, limited studies have been conducted that link human vulnerability to recent initiatives, such as reducing emissions from deforestation and forest degradation or REDD+, especially in highly vulnerable countries. Using case studies from the Philippines, this paper focuses on the vulnerability of two community-based forest management (CBFM) organizations, with and without REDD+ readiness intervention, to show the impacts of climate variability and extremes. Two balance-weighted approaches, the livelihood vulnerability index and the IPCC-framework, were used in the vulnerability assessments. Results revealed high vulnerability of both CBFM organizations, although Malitbog Upland Developers for Sustainable Association (MUDSA) livelihood vulnerability is largely aggravated by its exposure to disaster, climate variability and extremes, accessibility to health facilities and water supply. The long history of CBFM implementation in both organizations have minimal contribution in enhancing the adaptive capacity of members to cope with and adapt to climate change impacts. REDD+ (readiness), does not insure reduced vulnerability to climate change, unless sustainable livelihood is achieved. As the State controls forest resources, the rights of CBFM-organizations to commercially benefit from these resources are limited, a disincentive to the development of new and viable development programs in CBFM areas, such as REDD+. This also constrains the achievement of climate resiliency.  相似文献   
137.
ABSTRACT:   High- and multi-frequency acoustic measurement systems and the multi-frequency inversion (MFI) method have been used to measure spatial distributions and abundances of zooplankton by size. In this study, the calibration method for high- and multi-frequency systems was developed and the validation of MFI method was carried out by scatterer measurement. The standard sphere calibration method that has not been applied to such high- and multi-frequencies was applied to calibrate our high- and multi-frequency system, TAPS-6 (Tracor Acoustic Profiling System, BAE Systems). An optimum size of standard sphere of tungsten carbide of 1 mm radius was derived to have a small target strength variation for the six frequencies of TAPS-6, and the practicability and precision of the standard sphere calibration method was confirmed for those frequencies. A school or cluster of dummy scatterers of zooplankton with small tungsten carbide spheres were designed to validate the MFI method, and volume back-scattering strength values were measured by the multi-frequency system. By comparing the result of the inversion with their real composition, the features of the MFI method could be validated and examined.  相似文献   
138.
Adult Mesenchymal Stem Cells (MSC) are cells that can be defined as multipotent cells able to differentiate into diverse lineages, under appropriate conditions. These cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Initially discovered in bone marrow, MSC can now be isolated from a wide spectrum of adult and foetal tissues. Studies to evaluate the therapeutic potential of these cells are based on their ability to arrive to damaged tissues. In this paper we have done a comparative study analyzing proliferation, surface markers and OCT4, SOX9, RUNX2, PPARG genes expression in MSC cells from Bone marrow (BMMSC) and Adipose tissue (ASC). We also analyzed the role of Stem Cell Factor (SCF) on MSC proliferation and on ASCs metalloproteinases MMP-2, MMP-9 secretion. Healthy dogs were used as BMMSC donors, and ASC were collected from omentum during elective ovariohysterectomy surgery. Both cell types were cultured in IMDM medium with or without SCF, 10% Dog Serum (DS), and incubated at 38 °C with 5% CO2. Growth of BMMSCs and ASCs was exponential until 25–30 days. Flow citometry of MSCs revealed positive results for CD90 and negative for CD34, CD45 and MCH-II. Genes were evaluated by RT-PCR and metalloproteinases by zymografy. Our findings indicate morphological and immunological similarities as well as expression of genes from both origins on analyzed cells. Furthermore, SCF did not affect proliferation of MSCs, however it up-regulated MMP-2 and MMP-9 secretion in ASCs. These results suggest that metalloproteinases are possibly essential molecules pivoting migration.  相似文献   
139.
The effect of biotin supplementation on various foot lesions and hoof ceramide composition of toe (wall) and sole portions of hooves was studied in crossbred dairy cattle. Biotin supplementation was done for five months in 14 cattle at a farm and the other 14 animals kept as control. A significant decline was observed in heel erosions and sole avulsions along with total disappearance of white line fissures and double soles in the biotin supplemented cattle resulting in decrease in the overall disease score. Thin layer chromatographs of the hoof lipids revealed 11 types of ceramides in sole lipids and 6 types of ceramides in toe (wall) lipids. The ceramides were typed and identified according to their Rf values. A qualitative increase in the density of thin layer chromatographs of sole lipids was observed in biotin supplemented cattle whereas a non-significant difference in density of thin layer chromatographs of toe lipids was observed after supplementation of biotin.  相似文献   
140.
The objective of this study was to evaluate oxidative stress in lambs experimentally infected with Haemonchus contortus and supplemented with selenium and vitamin E. Twenty male Corriedale lambs were divided into four experimental groups with five animals each: G1 consisted of animals infected and supplemented with 0.2 mg/kg of live weight (LW) sodium selenite by intramuscular injection (IM); G2 consisted of animals infected with larvae and supplemented with 0.2 mg/kg LW sodium selenite IM and 2000 IU per animal of Vitamin E IM; G3 consisted of animals infected with larvae and supplemented with 2000 IU per animal of Vitamin E IM; and G4 consisted of animals infected with larvae. The animals were infected orally with 500 H. contortus larvae (L3) every 48 hours for 20 days. For biochemical analyses and eggs per grams of feces (EPG) evaluation, blood and feces were both collected at zero (T0), 20 (T1), 40 (T2) and 60 (T3) days. The weight of the animals was also measured at these times. Lower TBARS values were observed in the supplemented animals compared to the control group. The groups supplemented with Selenium exhibited blood GSH-Px activity higher than that of non-supplemented animals. Supplementation with selenium provided greater antioxidant protection against oxidative stress generated from experimental infection of lambs with H. contortus.  相似文献   
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