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91.
Global environmental change significantly affects marine species composition. However, analyzing the impact of these changes on marine zooplankton communities was so far mostly limited to assessing lethal doses through mortality assays and hence did not allow a direct assessment of the preferred conditions, or preferendum. Here, we use a microfluidic device to characterize individual behavior of actively swimming zooplankton, and to quantitatively determine their ecological preferendum. For the annelid zooplankton model Platynereis dumerilii we observe a broader pH preferendum than for the copepod Euterpina acutifrons, and reveal previously unrecognized sub-populations with different pH preferenda. For Platynereis, the minimum concentration difference required to elicit a response (responsiveness) is ~1 μM for H+ and ~13.7 mM for NaCl. Furthermore, using laser ablations we show that olfactomedin-expressing sensory cells mediate chemical responsiveness in the Platynereis foregut. Taken together, our microfluidic approach allows precise assessment and functional understanding of environmental perception on planktonic behaviour. 相似文献
92.
We have observed the rhythmic pattern of echinostome cercariae, infecting Lymnea stagnalis Linnaeus, 1758 in a freshwater body located near Barabanki. There is high cercarial shedding (74%) during dark phase (18.30–06.30 h), which is statistically significant (F = 861.04, p < 0.001). Sesonal pattern of rhythmicity shows maximum yield in summer months (April, May and June) and low yeild in February and July. Periodicity of 2 h shows their high shedding in dark phase (12.30–14.30 h). We also observed the effect of temperature at four different temperatures (10°, 15°, 20° and 25°) and their shedding was found to be high at 20 °C and low at 10 °C. Probably, in an effort to approach their intermediate hosts, they acquire this pattern of rhythmicity. 相似文献
93.
94.
Chakraborty T Pandey N Chatterjee A Ghosh B Rana B Chatterjee M 《Mutation research》2006,609(2):117-128
Carcinogen-induced DNA base modification and subsequent DNA lesions are the critical events for the expression of premalignant phenotype of the cell. We have therefore investigated the chemopreventive efficacy of a vanadium salt against diethylnitrosamine (DEN)-induced early DNA and chromosomal damages in rat liver. Hepatocarcinogenesis was induced in male Sprague-Dawley rats with a single, necrogenic, intraperitoneal injection of DEN (200mg/kg body weight). 8-Hydroxy-2'-deoxyguanosines (8-OHdGs), strand-breaks and DNA-protein crosslinks (DPCs) were measured by HPLC, comet assay and spectrofluorimetry, respectively. There was a significant and steady elevation of modified bases 8-OHdGs along with substantial increments of the extent of single-strand-breaks (SSBs), DPCs and chromosomal aberrations (CAs) following DEN exposure. Supplementation of vanadium as ammonium metavanadate (NH(4)VO(3), +V oxidation state) at a dose of 0.5ppm in terms of the salt weight throughout the experiment abated the formations of 8-OHdGs (P<0.0001; 79.54%), tailed DNA (P<0.05; 31.55%) and length:width of DNA mass (P<0.02; 61.25%) in preneoplastic rat liver. Vanadium treatment also inhibited DPCs (P<0.0001; 58.47%) and CAs (P<0.001; 45.17%) studied at various time points. The results indicate that the anticlastogenic potential of vanadium in vivo might be due to the observed reductions in liver-specific 8-OHdGs, SSBs and/or DPCs by this trace metal. We conclude that, vanadium plays a significant role in limiting DEN-induced genotoxicity and clastogenicity during the early stages of hepatocarcinogenesis in rats. 相似文献
95.
Treatment of dyed effluents presents several problems mainly due to the toxicity and recalcitrance of dyestuffs. Innovative technologies, such as biosorption, are needed as alternatives to conventional methods to find inexpensive ways of removing dyes from large volumes of effluents. Inactivated biomasses do not require a continuous supply of nutrients and are not sensitive to the toxicity of dyes or toxic wastes. They can also be regenerated and reused in many cycles and are both safe and environment-friendly. The sorption capacities (SC) of autoclaved biomasses of three Mucorales fungi (Cunninghamella elegans, Rhizomucor pusillus and Rhizopus stolonifer), cultured on two different media, were evaluated against simulated effluents containing concentrations of 1000 and 5000 ppm of a single dye and a mix of 10 industrial textile dyes in batch experiments. SC values of up to 532.8 mg of dye g(-1) dry weight of biomass were coupled with high effluent decolourisation percentages (up to 100%). These biomasses may thus prove to be extremely powerful candidates for dye biosorption from industrial wastewaters. Even better results were obtained when a column system with the immobilised and inactivated biomass of one fungus was employed. 相似文献
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97.
Abstract In Italy, Corynephorus communities are distributed along the medium course of the Ticino river and Sesia river and the internal sand dunes of Lomellina (through the Vercelli, Novara and Pavia provinces); these stations represent the southern limit of European distribution of this habitat. A phytosociological study was carried out to gain better knowledge of their composition; of their affinity or diversity against the central European communities; of their distribution and of the main threats to their conservation. Original and literature relevés (114) were elaborated producing a cluster analysis; correspondence analysis (CA), principal component analysis and Kruskal–Wallis test were carried on to characterize the clusters of relevés taking into consideration biological forms, chorological groups, Ellenberg indicator values and floristic groups. Italian Corynephorus communities can be attributed to the following syntaxa: Spergulo vernalis-Corynephoretum canescentis, Spergulo vernalis-Corynephoretum canescentis cladonietosum, Spergulo vernalis-Corynephoretum canescentis silenetosum nutantis and Spergulo vernalis-Corynephoretum canescentis artemisietosum campestris. Italian Corynephorus communities are included in the Habitat 2330 of the EU Habitat Directive. They are threatened by different factors (such as restricted areas of occurrence, alien plant invasion and natural dynamics) and they need to be managed if we want to conserve them. 相似文献
98.
Sperata aor commonly called as long- whiskered cat fish or “Bada Tengan” in local fish markets harboured one new and one
previously known species of genus Thaparocleidus Jain, 1952, along with two species of Cornudiscoides Kulkarni, 1969, infesting gills.
Thaparocleidus aori (Rizvi, 1971) Lim, 1996, was earlier described by Rizvi therefore was briefly recorded in the present study, except
the egg. The newly found species Thaparocleidus susanae n.sp was characterized by the structure of its peculiar copulatory organ.
Phylogenetic relationship of the two species under study, along with 14, reterived from GenBank was established using the
sequences of 28S rDNA region (Dactylogyrus Diesing, 1850 taken as an out group). 相似文献
99.
Singh AK Kant S Parshad R Banerjee N Dey S 《Biochemical and biophysical research communications》2011,(2):304-308
The high concentration of prostaglandins has been associated with chronic inflammatory diseases and several types of human cancers. This is due to the over expression of inflammatory enzymes like Cyclooxygenase (COX), Lipoxygenase (LOX) etc. The aim of this study was to quantify the LOX-12 with clinicopathological parameter of breast cancer patients and its response after chemotherapy to establish serum LOX-12 as a prognostic marker. This case-controlled study was performed on 86 biopsy proven breast cancer patients. Blood and tissue samples were collected from the patients. Serum LOX-12 of the study group was quantified by Surface Plasmon Resonance (SPR) and ELISA techniques by antibody–antigen interaction strategy. A significant increase in LOX-12 levels was observed in breast cancer patients (Mean ± SD = 40.54 ± 13.61 ng/ml) as compared to healthy controls (Mean ± SD = 13.42 ± 2.4 ng/ml) (p < 0.0001). Serum LOX-12 levels were significantly higher (p < 0.002) in patients with lymph node involvement. More than 75% patients had shown significant (p < 0.0001) reduction of LOX-12 levels after chemotherapy. This was also confirmed by ELISA. This study for the first time had co-related the quantity of serum LOX-12 with breast cancer and also with the effect of chemotherapy. 相似文献
100.