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Environmental and spatial characterisation of an unknown fauna using DNA sequencing – an example with Himalayan Hydropsychidae (Insecta: Trichoptera) 下载免费PDF全文
Felicitas Hoppeler Ram Devi Tachamo Shah Deep Narayan Shah Sonja C. Jähnig Jonathan D. Tonkin Subodh Sharma Steffen U. Pauls 《Freshwater Biology》2016,61(11):1905-1920
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A study was conducted to determine the efficacy of β-mannanase supplementation to a diet based on corn and soya bean meal (SBM) on growth performance, nutrient digestibility, blood urea nitrogen (BUN), faecal coliforms and lactic acid bacteria, and noxious gas emission in growing pigs. A total of 140 pigs [(Landrace × Yorkshire) × Duroc; average body weight 25 ± 3 kg] were randomly allotted to a 2 × 2 factorial arrangement with dietary treatments consisting of hulled or dehulled SBM without or with supplementation of 400 U β-mannanase/kg. During the 6 weeks of experimental feeding, β-mannanase supplementation had no effect on body weight gain, feed intake and gain:feed (G:F) ratio. Compared with dehulled SBM, feeding hulled SBM caused an increased feed intake of pigs in the entire trial (p = 0.05). The G:F ratio was improved in pigs receiving dehulled SBM (p < 0.05). Dietary treatments did not influence the total tract digestibility of dry matter, nitrogen and gross energy. Enzyme supplementation reduced (p < 0.05) the population of faecal coliforms and tended to reduce the NH3 concentration after 24 h of fermentation in a closed box containing faecal slurry. Feeding hulled SBM tended to reduce NH3 emission on days 3 and 5 of fermentation. In conclusion, mannanase supplementation had no influence on growth performance and nutrient digestibility but showed a positive effect on reducing coliform population and tended to reduce NH3 emission. Dehulled SBM increased G:F ratio and hulled SBM tended to reduce NH3 emission. 相似文献
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A. B. Shreya Renuka S. Managuli Jyothsna Menon Lavanya Kondapalli Aswathi R. Hegde Kiran Avadhani 《Journal of liposome research》2016,26(3):221-232
Context: Asenapine maleate (ASPM) is an antipsychotic drug for the treatment of schizophrenia and bipolar disorder. Extensive metabolism makes the oral route inconvenient for ASPM.Objective: The objective of this study is to increase ASPM bioavailability via transdermal route by improving the skin permeation using combined strategy of chemical and nano-carrier (transfersomal) based approaches.Materials and methods: Transfersomes were prepared by the thin film hydration method using soy-phosphatidylcholine (SPC) and sodium deoxycholate (SDC). Transfersomes were characterized for particle size, polydispersity index (PDI), zeta potential (ZP), entrapment efficiency, surface morphology, and in vitro skin permeation studies. Various chemical enhancers were screened for skin permeation enhancement of ASPM. Optimized transfersomes were incorporated into a gel base containing suitable chemical enhancer for efficient transdermal delivery. In vivo pharmacokinetic study was performed in rats to assess bioavailability by transdermal route against oral administration.Results and discussion: Optimized transfersomes with drug:SPC:SDC weight ratio of 5:75:10 were spherical with an average size of 126.0?nm, PDI of 0.232, ZP of??43.7?mV, and entrapment efficiency of 54.96%. Ethanol (20% v/v) showed greater skin permeation enhancement. The cumulative amount of ASPM permeated after 24?h (Q24) by individual effect of ethanol and transfersome, and in combination was found to be 160.0, 132.9, and 309.3?μg, respectively, indicating beneficial synergistic effect of combined approach. In vivo pharmacokinetic study revealed significant (p?0.05) increase in bioavailability upon transdermal application compared with oral route.Conclusion: Dual strategy of permeation enhancement was successful in increasing the transdermal permeation and bioavailability of ASPM. 相似文献
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Ramnath RD Sun J Adhikari S Bhatia M 《Journal of cellular and molecular medicine》2007,11(6):1326-1341
Substance P, acting via its neurokinin 1 receptor (NK1 R), plays an important role in mediating a variety of inflammatory processes. Its interaction with chemokines is known to play a crucial role in the pathogenesis of acute pancreatitis. In pancreatic acinar cells, substance P stimulates the release of NFκB-driven chemokines. However, the signal transduction pathways by which substance P-NK1 R interaction induces chemokine production are still unclear. To that end, we went on to examine the participation of mitogen-activated protein kinases (MAPKs) in substance P-induced synthesis of pro-inflammatory chemokines, monocyte chemoanractant protein-1 (MCP-I), macrophage inflammatory protein-lα (MIP-lα) and macrophage inflammatory protein-2 (MIP-2), in pancreatic acini. In this study, we observed a time-dependent activation of ERK1/2, c-Jun N-terminal kinase (JNK), NFκB and activator protein-1 (AP-1) when pancreatic acini were stimulated with substance P. Moreover, substance P-induced ERK 1/2, JNK, NFκB and AP-1 activation as well as chemokine synthesis were blocked by pre-treatment with either extracellular signal-regulated protein kinase kinase 1 (MEK1) inhibitor or JNK inhibitor. In addition, substance P-induced activation of ERK 112, JNK, NFκB and AP-1-driven chemokine production were attenuated by CP96345, a selective NK1 R antagonist, in pancreatic acinar cells. Taken together, these results suggest that substance P-NK1 R induced chemokine production depends on the activation of MAPKs-mediated NFκB and AP-1 signalling pathways in mouse pancreatic acini. 相似文献
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Protective effect of Abutilon indicum against lead-induced reproductive toxicity in male Wistar rats
Despite ample literature on the toxic impact of lead on the environment and health, the exact mechanism of pathogenesis/toxicity is not clearly known. Because it is well established that lead induces oxidative stress, it is assumed that exposure to antioxidants may reduce the toxic impact of lead. In this study, we evaluated the impact of coadministration of the methanolic root extract of a plant Abutilon indicum (50, 100, 200 mg kg −1b.wt.) in mitigating the toxic impact of lead on the reproductive system of rats. In brief, Wistar rats were exposed to lead acetate in drinking water with or without coadministration of plant root extract and compared with that of control animals. After 45 days of exposure as outlined above, the animals were killed and the reproductive toxicity was assessed by sperm parameters, hormone and antioxidant enzyme assays, and testis histopathology. Significant reduction in testis weight, sperm count, testosterone levels, and antioxidant enzymes levels such as Superoxide Dismutase, Catalase, and Glutathione peroxidase was seen in lead-treated animals, confirming the toxic impact. The coadministration of A. Indicum (100 and 200 mg kg −1b.wt.) was found to bring the studied parameters close to the levels seen in untreated (control) animals. Our findings are indicative of the protective nature of A. Indicum against lead-induced reproductive toxicity in a dose-dependent manner. However, further characterization of the root extract is required to elucidate the probable mechanism of protection. 相似文献
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