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41.

Purpose

Coal-fuelled power plants can discharge hazardous materials, particularly heavy metals such as lead (Pb). An alternative way of reducing Pb concentration from contaminated sediments is through phytoremediation. Presently, there are few research findings on the phytoremediation potential of mangroves on metals like Pb. The study was conducted to survey and identify mangroves that thrive near the coal-fired power plant and to assess the phytoremediation potential of mangroves on Pb in sediment.

Materials and methods

The study sites were located in the mangrove ecosystems of Sitio Oyon and Sitio Asinan in Masinloc, Zambales, Philippines. The first stage of our study was to survey and identify the mangrove species. The second stage was to assess the levels of Pb in the sediments, water, and tissues of mangrove trees. The diversity assessment of the mangrove species was done through the use of 10?×?12 m quadrat technique. Water and sediment samples from each mangrove ecosystem were collected using composite sampling methods.

Results and discussion

Three mangrove species were identified in the study sites: Avicennia marina, Rhizophora stylosa, and Sonneratia alba. The order of importance of the mangrove trees in the two sampling locations, based on an importance value index (IVI), were as follows: SA (IVI?=?171.20)?>?AM (77.79)?>?RS (51.01). The total uptake of Pb from sediments near the power plants varied significantly (p?≤?0.001) among the three mangrove species. S. alba had the highest Pb uptake of 48.4 kg ha?1 followed by A. marina (23.1 kg ha?1), and R. stylosa (2.4 kg ha?1). These three mangrove species have the potential to phytoremediate Pb in the sediment.

Conclusions

The three mangrove species present in the coastal ecosystem near the electric power plant—A. marina, R. stylosa, and S. alba—were potential phytoremediators of sediment Pb. The present study indicated that the mangroves possess beneficial characteristics that remove Pb from contaminated sediments in areas directly affected by coal-fired power plants, and thus have potential phytoremediation properties.  相似文献   
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Individuals of two porcupine species (Coendou prehensilis and Coendou melanurus) were translocated during the flooding of a forest at a hydroelectric dam site in French Guiana. Blood samples were collected for 11 mo to determine hematologic and serum chemistry reference mean values and ranges and to look for blood parasites. Male C. prehensilis had significantly higher hemoglobin levels, packed cell volumes, and creatinine and potassium values than did females of the same species. Coendou prehensilis had significantly lower amylase levels but higher creatinine, calcium, lactate dehydrogenase, and gamma glutamyl transferase levels than C. melanurus.  相似文献   
45.
The ballan wrasse (Labrus bergylta) is a marine fish belonging to the family Labridae characterized by 2 main morphotypes that occur in sympatry: spotty and plain. Previous studies have revealed differences in their life‐history traits, such as growth and maturation; however, the genetic relationship between forms is presently unknown. Using 20 recently developed microsatellite markers, we conducted a genetic analysis of 41 and 48 spotty and plain ballan wrasse collected in Galicia (northwest Spain). The 2 morphotypes displayed highly significant genetic differences to each other (FST = 0.018, P < 0.0001). A similar degree of genetic differentiation (FST = 0.025, P < 0.0001) was shown using the STRUCTURE clustering approach with no priors at K = 2. In this case, the frequency of spotty and plain morphotypes was significantly different (χ2 = 9.46, P = 0.002). It is concluded that there is significant genetic heterogeneity within this species, which appears to be highly associated with the spotty and plain forms, but not completely explained by them. Given the previously demonstrated biological differences between morphotypes, and the present genetic analyses, we speculate about the convenience of a taxonomic re‐evaluation of this species.  相似文献   
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Objective

The objective of the study was to determine the effect of gentamicin on CD3+ T-lymphocyte proliferation and cell viability using an in vitro cell culture model as a means of investigating the mechanism of action of low-dose intravitreal gentamicin injection.

Animals Studied

Three adult horses with no evidence of ophthalmic or systemic disease.

Procedure

Peripheral blood lymphocytes were treated with gentamicin at concentrations 37.5 μg/mL, 112.5 μg/mL, 187 μg/mL, 375 μg/mL, or 750 μg/mL then stimulated to proliferate with concanavalin A (ConA). 4′,6-diamidino-2-phenylindole (DAPI) and carboxyfluoroscein succinimidyl ester (CSFE) were used as markers of cell viability and cell proliferation, respectively. Following 5-day culture, live cell counts and CSFE fluorescent intensity data were collected via automated cell count and flow cytometry. The experimental design was duplicated using preservative-free gentamicin and a proprietary brand formulation. Statistical analysis was performed using two-way ANOVA with Tukey's multiple comparison test.

Results

No statistically significant comparisons in CD3+ T-lymphocyte live cell counts and geometric mean fluorescent intensity of CSFE were identified between gentamicin concentrations or formulations.

Conclusions

Gentamicin had no effect on equine peripheral blood CD3+ T-lymphocyte cell viability and proliferation in concentrations ranging from “safe” to “retinotoxic” in relation to intravitreal injection volumes. Low-dose intravitreal gentamicin may not suppress the Th1- and Th17-mediated immune response.  相似文献   
48.
A HPLC-UV method for the quantification of six major isoflavonoids, calycosin 7-O-beta-D-glucoside (1), formononetin 7-O-beta-D-glucoside (2), (6alphaR, 11alphaR) 3-hydroxy-9,10-dimethoxypterocarpan-3-O-beta-D-glucoside (3), 7,2'-dihydroxy-3',4'-dimethoxyisoflavan-7-O-beta-D-glucoside (4), calycosin (5) and formononetin (6), in Radix Astragali (Huangqi) was developed and validated. The method was proven to be sensitive, specific, accurate and precise, as well as effective and easy.  相似文献   
49.
Tomato pomace, delignified by the edible oyster mushroom, Pleurotus ostreatus, could be used as a poultry feed ingredient to provide alpha-tocopherol for retardation of lipid oxidation in postmortem meat if the antioxidant were retained in pomace after fungal fermentation. Experiments were conducted to investigate changes in the content of alpha-tocopherol, lycopene, and beta-carotene in tomato pomace after sterilization and treatment with P. ostreatus from 0 to 104 days. alpha-Tocopherol (39.26 to 31.15 microg/g) and lycopene (17.42 to 11.19 microg/g) significantly decreased during sterilization while beta-carotene (42.56 to 35.44 microg/g) did not. The content of carotenoids decreased by day 26 as compared to 0 day for the control and for treated samples. alpha-Tocopherol decreased during fungal fermentation at day 26 as compared to 0 day for the control and increased during the same period for treated samples. By 104 days, only alpha-tocopherol in control pomace was present in a significant amount. The alpha-tocopherol content of mushroom fruit grown in pomace (74.10 microg/g) and in wheat straw (51.36 microg/g) was not significantly different. Tomato pomace could be used as a substrate to successfully grow edible mushrooms; however, the initial level of selected antioxidants and their reduction during fungal fermentation must be considered when delignified pomace is utilized for selected nutrient content in animal feed or products for human consumption.  相似文献   
50.
Previous structural studies of the lipopolysaccharides from the veterinary pathogens Mannheimia haemolytica (Mh), Actinobacillus pleuropneumoniae (Ap) and Pasteurella multocida (Pm) had identified a conserved inner core oligosaccharide structure that was present in all strains investigated. In order to examine the potential of this inner core structure as a vaccine, a mutagenesis strategy was adopted to interrupt a D-glycero-D-manno-heptosyltransferase gene (losB) of Mh. This gene encodes the enzyme responsible for the addition of a D-glycero-D-manno-heptose residue, the first residue beyond the conserved inner core, and its inactivation exposed the conserved inner core structure as a terminal unit on the mutant LPS molecule. Subsequent analyses confirmed the targeted structure of the mutant LPS had been obtained, and complementation with losB in trans confirmed that the losB gene encodes an alpha-1,6-D-glycero-D-manno-heptosyltransferase. Monoclonal antibodies raised in mice to this LPS structure were found to recognise LPS and whole-cells of the truncated mutant and wild-type Mh. The antibodies were bactericidal against a wild-type Mh strain and were able to passively protect mice in a model of Mh disease. This illustrates that it is possible to raise functional antibodies against the conserved inner core LPS structure.  相似文献   
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