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1.
Identification of internal control genes in milk‐derived mammary epithelial cells during lactation cycle of Indian zebu cow 
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Antimicrobial peptides expressed on different epithelial lining are major components of the innate immune system. Based on
the deduced amino acid sequence of Bubalus bubalis lingual antimicrobial peptide (LAP) cDNA (Accession No. DQ458768), five overlapping peptides LAP23–55, LAP42–64, LAP21–64, LAP1–26 and LAP1–64 were synthesized using solid phase fluorenylmethoxycarbonyl (Fmoc) chemistry. Circular Dichroism spectroscopy of synthesized
peptides revealed predominantly β-structure for LAP23–55, LAP42−64 and LAP21–64 with less α-helix in different solutions. Quantitation of secondary structure indicated the highest β-structure for all these
three peptides in membrane mimetic SDS solution. The helicogenic solvent TFE could not induce helix in LAP23–55 however TFE induced helical propensity was observed in LAP42–64 and LAP21–64. The quantitation of secondary structure indicated the highest ordered structure for LAP23–55 followed by LAP42–64 and LAP21–64. The antibacterial activity of LAP23–55 was found to be more potent against Staphylococcus aureus, Listeria monocytogens, Escherichia coli and Salmonella typhimurium followed by LAP42–64 and LAP21–64. Minimum inhibitory concentration (MIC) also showed similar trend with lowest value for LAP23–55 followed by LAP42–64 and LAP21–64. Haemolysis and cytotoxicity was observed above 3 fold for LAP21–64, above six fold for LAP23–55 and LAP42–64 of their MIC. The LAP1–26 and LAP1–64 could not produce any characteristic CD spectra and did not show any antimicrobial activity, indicating that N- terminal
of the peptide negates the antimicrobial activity. 相似文献
3.
为探讨气单胞菌在不同食物接触表面的存活状况,采用擦拭取样法测定气单胞菌于案板、刀具表面的恢复率,并将气单胞菌分别接种于洁净和被污染的案板、刀具表面,评定气单胞菌在不同介质表面、不同时间下的存活状况。根据恢复率和介质表面上气单胞菌存活实测值,采用@Risk软件对介质表面实时带菌量的期望值进行计算,并运用一级线性模型对气单胞菌存活特征曲线进行拟合。同时,以案板为交叉污染途径,对气单胞菌在介质表面的存活行为对交叉污染的影响进行了探讨。结果表明:采用擦拭取样法测得的气单胞菌从案板、刀具表面的恢复率的最佳分布拟合结果分别是Normal(0.66,0.15)和Normal(0.72,0.18);气单胞菌在被污染的介质表面存活的时间(7 h)长于其在洁净介质表面的存活时间(3 h或2.5 h),且一级线性模型可以较好地对气单胞菌存活曲线进行拟合(R20.88);蒙特卡罗模拟结果表明,忽略气单胞菌在食物接触表面的存活行为会高估其在厨房内的交叉污染水平。 相似文献
4.
Chemical and mineralogical properties of a soil chronosequence in the high mountain zone between 3857 m and 4120 m a.s.l. in Central Nepal (Langtang valley) are presented. The soils have been developed in moraine deposits which consist of acid gneisses. They were classified as Entisols, and Spodosols. XRD analyses of the clay and fine silt fraction show increasing changes with distance from the recent Lirung glacier, depending on the time of deposition, resp. soil age. Alteration of illite to interstratified minerals and to hydroxy-Al interlayered minerals or pedogenic chlorite with increasing soil development could be observed. The interstratified minerals could be identified as random and regular illite-interlayered vermiculite mixed-layer minerals. Intensification of the X-ray signals of the fine silt fraction is given compared to the clay. With increasing soil development differences between the clay and fine silt fraction seem to increase. Indications are given of interstratification of the mica-pedogenic chlorite and chloriteinterlayered vermiculite type in the more intensively weathered soils. 相似文献
5.
为定量描述气单胞菌在不同介质间的转移及变化过程,基于单个细菌在每次转移过程中只能被转移到一个介质表面的假设,采用矩阵方式将气单胞菌的转移路径及被转移的可能性集中于一个二维的数据表格之中,并对不同场景下气单胞菌在不同介质表面的交叉污染水平进行分析。结果表明,采用矩阵方式不仅可用于探究交叉污染对细菌受体表面带菌量的变化,同时可定量分析细菌供体表面带菌量的变化,如在分割冷却猪肉前、后,猪肉中气单胞菌的带菌量平均值分别为3.02 lg CFU/g、1.82 lg CFU/g。对不同场景下各介质带菌量的量化结果证实:分割冷却猪肉后,若及时对被污染的案板、刀具等介质进行清洗或更换,可有效降低交叉污染水平并可预防二次交叉污染的发生。 相似文献
6.
Akshey YS Malakar D De AK Jena MK Sahu S Dutta R 《Reproduction in domestic animals》2011,46(4):699-704
The present investigation was carried out to find an efficient chemically assisted procedure for enucleation of goat oocytes related to handmade cloning (HMC) technique. After 22-h in vitro maturation, oocytes were incubated with 0.5 μg/ml demecolcine for 2 h. Cumulus cells were removed by pipetting and vortexing in 0.5 mg/ml hyaluronidase, and zona pellucida were digested with pronase. Oocytes with extrusion cones were subjected to oriented bisection. One-third of the cytoplasm with the extrusion cone was removed with a micro blade. The remaining cytoplasts were used as recipients in HMC. Goat foetal fibroblasts were used as nuclear donors. The overall efficiency measured as the number of cytoplasts obtained per total number of oocytes used was significantly (p < 0.05) higher in chemically assisted handmade enucleation (CAHE) than oriented handmade enucleation without demecolcine (OHE) (80.02 ± 1.292% vs. 72.9 ± 1.00%, respectively, mean ± SEM). The reconstructed and activated embryos were cultured in embryo development medium (EDM) for 7 days. Fusion, cleavage and blastocyst development rate were 71.63 ± 1.95%, 92.94 ± 0.91% and 23.78 ± 3.33% (mean ± SEM), respectively which did not differ significantly from those achieved with random handmade enucleation and OHE. In conclusion, chemically assisted enucleation is a highly efficient and reliable enucleation method for goat HMC which eliminates the need of expensive equipment (inverted fluorescence microscope) and potentially harmful chromatin staining and ultraviolet (UV) irradiation for cytoplast selection. 相似文献
7.
Arun Kumar De Dhruba MalakarManoj Kumar Jena Rahul DuttaShweta Garg Yogesh S. Akshey 《Livestock Science》2012,143(1):35-42
Studies on parthenogenetic activation of oocytes are important to improve the efficiency of nuclear transfer as artificial activation of oocytes is an essential component of nuclear transfer protocol. The present study was carried out to investigate the effects of different activation methods, culture systems and culture media on in vitro development of zona-free and with-zona parthenogenetic embryos in goat. In case of zona-free parthenogenesis, there was a significant (p < 0.05) increase in cleavage rate and blastocyst yield when oocytes were activated by electrical pulse (76.29 ± 0.52% and 19.07 ± 0.39% respectively) than when Ca-ionophore was used for activation (63.45 ± 0.73% and 14.09 ± 0.65% respectively). The quality of blastocysts was evaluated by determination of cell number and by expression profile of pluripotent related gene Oct-4. No significant (p < 0.05) difference was found in quality of blastocysts produced by different activation methods. In culturing of zona-free parthenogenetic embryos, flat surface (FS) was proved to be the best system. A significant (p < 0.05) decrease in cleavage rate and blastocyst yield was found in Microdrop culture of zona-free embryos (43.67 ± 2.08% and 0.72 ± 0.72% respectively) in comparison to WOW of zona-free embryos (73.88 ± 1.70% and 15.51 ± 1.34% respectively) and FS of zona-free (75.14 ± 0.81% and 23.93 ± 2.71% respectively) as well as with-zona (72.16 ± 1.55% and 18.16 ± 0.68%) embryos. Zona-free flat culture system yielded significantly (p < 0.05) higher blastocyst rate than zona-free WOW system as well as with-zona flat culture system. The zona-free and with-zona parthenogenetic embryos were cultured in three different media — Research Vitro Cleave media from Cook® Australia (RVCL), Embryo Development Medium (EDM) and Modified Synthetic Oviductal Fluid (mSOF). In case of zona-free parthenogenesis, significant (p < 0.05) increase was found in blastocyst development rate in RVCL medium (18.61 ± 1.52%) than EDM (11.29 ± 0.77%) or mSOF (11.53 ± 1.86%). In case of with-zona parthenogenesis, RVCL medium and EDM were found superior to mSOF. The results of the study will be helpful to improve the efficiency of nuclear transfer in goat. 相似文献
8.
In this paper, we report the development, characterization and bioefficacy evaluation of fipronil nanoformulations against brown plant hopper (BPH); Nilaparvata lugens in rice. Nanoformulations were characterized for nanosizing and stability under variable conditions. Bioefficacy of nanoformulations were evaluated under field condition at farms of Indian Agricultural Research Institute, New Delhi during Kharif 2015. At milking stage BPH populations were above economic threshold level; followed by foliar application of fipronil nanoformulations at four doses (viz., 30, 45, 60 and 90 g a.i./ha) along with commercial formulation of fipronil. The mean mortality clearly indicated that all the insecticidal treatments were significantly superior over untreated control where, highest mortalities were observed in nanodispersions followed by monolithic dispersion and commercial formulation of fipronil. Treated plots 7 days after application @ 60 g a.i./ha has shown 93.47%, 86.89% and 80.47% reduction BPH population in nanodispersion, encapsulated monolithic dispersion and commercial formulation treated plots respectively. In comparison to commercial formulation @ 60 g a.i./ha yield has increased by 0.56 t ha?1 (28.76%) and 0.26 t ha?1 (14.04%) in nanodispersion and monolithic dispersion. 相似文献
9.
In spite of the tremendous public interest in the recent large honeybee losses attributed to colony collapse disorder, there is still no definitive explanation for the phenomenon. With the hypothesis that nutritional stress due to habitat loss has played an important role in honeybee colony collapse, I analyze the land use data in United States to show that the colony loss suffered by each state is significantly predicted by the extent of its open land relative to its developed land area. I provide further support for this hypothesis by showing that states with the largest areas of open land have a significantly higher honey yield on a per colony basis. I discuss how increasing loss of foraging resources could be synergistically acting with emerging diseases to stress honeybee populations and the importance therefore for preserving natural areas that act as important pollinator habitats. 相似文献