Enhanced chemiluminescent enzyme immunoassay for the detection of trichinellosis antibodies in pigs.   总被引：1，自引：0，他引：1  

R C Ko  M H Yeung 《Veterinary parasitology》1992,42(1-2):101-110

A modified enhanced chemiluminescent enzyme assay (ECIA) was developed for mass screening of pigs for trichinellosis antibodies in abattoirs. Using Bionectics beads as solid support, the assay time could be reduced to 45 min. Optimal conditions for washing, blocking, incubation, concentration of serum, antigens and conjugates as well as timing of film exposure were determined. The sensitivity and specificity of the assay were found to be comparable to those of the triple antibody-IgG ELISA. The assay was tested in an abattoir and its efficacy was found to be satisfactory. However, the major disadvantage of the assay is the high cost of magnetic beads.  相似文献   

传染性法氏囊病病毒变异株主要免疫原基因cDNA的克隆及鉴定   总被引：3，自引：2，他引：1  

曹永长  毕英佐  罗文新  杨永成  梁志清  林文量 《中国兽医杂志》1997,(9)

采用反转录－聚合酶链反应（ＲＴ－ＰＣＲ），从１株传染性法氏囊病病毒（ＩＢＤＶ）本地分离株ＧＺ９０２中扩增到编码ＩＢＤＶ主要免疫蛋白ＶＰ２的ｃＤＮＡ片断，大小约为１３５０ｂｐ。将该ｃＤＮＡ片断插入ｐＢｓＫ质粒中，用重组质粒转化大肠杆菌ＸＬ１－Ｂｌｕｅ，成功获得重组质粒转化菌。对重组质粒ＤＮＡ进行酶切鉴定，证明插入的ＤＮＡ片断与ＰＣＲ扩增的ＤＮＡ片段大小相符。对ＧＺ９０２高可变区进行了序列分析。其核苷酸序列与３株ＩＢ－ＤＶ变异株Ａ、ＧＬＳ、Ｅ的同源性分别达到９８．９％，９６．２％和９５．５％。而与其他Ⅰ型毒株的同源性较低。比较从ＤＮＡ序列推导出的氨基酸序列，发现ＧＺ９０２高可变区的两个亲水区均发生了一个氨基酸的变化，而在２４９和２５４位上的氨基酸分别为Ｋ和Ｓ，与以上３个变异株相同，但与所有标准Ⅰ型毒株不同。这两个氨基酸可以作为ＩＢＤＶ变异株的标志。  相似文献   

New approaches for the effective recovery of fish proteins and their physicochemical characteristics   总被引：1，自引：0，他引：1  

Young Sin  KIM  Jae Won  PARK  Yeung Joon  CHOI 《Fisheries Science》2003,69(6):1231-1239

  相似文献   

Effects of deposition parameters of electroless copper plating on polyester fabric     

R. H. Guo  S. X. Jiang  C. W. M. Yuen  M. C. F. Ng  J. W. Lan  Y. L. Yeung  S. J. Lin 《Fibers and Polymers》2013,14(5):752-758

Properties of electroless copper-plated polyester fabric mainly depend on the plating bath constituents/conditions. The nickel serves to catalyze the copper deposition when hypophosphite is used as a reducing agent. In this study, the effects of deposition parameters including additive NiSO₄ concentration and pH on microstructure and properties of the electroless copper plating on polyester fabric using hypophosphite as a reducing agent were investigated. The results show that at a higher NiSO₄ concentration, the copper content present in the coating decreases whereas the nickel content increases slightly. On the other hand, the copper content present in the coating increases, whereas the nickel content and phosphorus decreases with respect to the rise of pH. The morphology of the copper deposits show that the particle size increase with respect to the rise of NiSO₄ concentration and pH. The XRD patterns indicate that the copper-plated polyester fabrics are crystalline. In addition, there is a decrease in the surface resistance and an increase in the electromagnetic interference (EMI) shielding effectiveness (SE) with respect to the rise of Ni²⁺ concentration and pH of the solution as a result of gaining a greater weight in the deposits. The results suggest that the copper-plated polyester fabrics have a great potential application as an EMI shielding material.  相似文献   

Immunohistochemical characterization of feline lymphoplasmacytic anterior uveitis     

Lawrence Crossfield  Luca Fortuna  Rebekah Carling  Emma Scurrell  Marian Matas Riera  Yu‐Mei Chang  Charlotte Dawson  Rachael Pittaway  Ian YL Yeung  Caroline Thaung  Simon L Priestnall  Oliver A Garden 《Veterinary ophthalmology》2019,22(2):206-212

  相似文献   

Effect of rapamycin treatment during post‐activation and/or in vitro culture on embryonic development after parthenogenesis and in vitro fertilization in pigs          下载免费PDF全文

F Elahi  H Lee  J Lee  ST Lee  CK Park  S‐H Hyun  E Lee 《Reproduction in domestic animals》2017,52(5):741-748

This study investigated the effects of early induction of autophagy on embryonic development in pigs. For this, oocytes or embryos were treated with an autophagy inducer, rapamycin (RP), during post‐activation (Pa), in vitro fertilization (IVF) and/or in vitro culture (IVC). When parthenogenesis (PA) embryos were untreated (control) or treated with various concentrations of RP for 4 hr during Pa, 100 nm RP showed a higher blastocyst formation (48.8 ± 2.7%) than the control (34.6 ± 3.0%). When PA embryos were treated during the first 24 hr of IVC, blastocyst formation was increased (p < .05) by 1 and 10 nm RP (61.9 ± 3.0 and 59.6 ± 3.0%, respectively) compared to the control (43.2 ± 1.8%) and 100 nm RP (47.8 ± 3.2%), with a higher embryo cleavage in response to 10 nm RP (87.3 ± 2.4%) than the control (74.1 ± 3.2%). RP treatment during IVC and Pa + IVC showed increased blastocyst formation (44.7 ± 2.5 and 44.1 ± 2.0%, respectively) compared to the control (33.2 ± 2.0%). In addition, RP treatment during Pa and/or IVC increased glutathione content and inversely reduced reactive oxygen species. In IVF, RP treatment for 6 hr during IVF significantly increased embryonic development (34.0 ± 2.6%) compared to the control (24.8 ± 1.6%), but treatment during IVC for 24 hr with RP did not (23.0 ± 3.8%). Autophagy was significantly increased in PA oocytes by the RP treatment during Pa but not altered by the treatment during the first 24 hr of IVC. Overall, RP treatment positively regulated the pre‐implantation development of pig embryos, probably by regulating cellular redox state and stimulating autophagy.  相似文献   

Iron bioavailability to piglets from red and white common beans (Phaseolus vulgaris)     

Tan SY  Yeung CK  Tako E  Glahn RP  Welch RM  Lei X  Miller DD 《Journal of agricultural and food chemistry》2008,56(13):5008-5014

Polyphenols in foods may chelate dietary Fe and lower its bioavailability. Concentrations of phenols are higher in red beans than in white beans. The aim of this study was to compare iron bioavailabilities from red and white beans in a piglet hemoglobin repletion model. Fe deficient cross bred piglets (Hampshire x Landrace x Yorkshire) were used. Nutritionally balanced diets (except for Fe) were formulated to contain 50% precooked, dehydrated beans (either small red or Great Northern white). At age 5 weeks, the piglets were assigned to two groups and fed diets containing either red or white beans for 4 weeks. Weight and hemoglobin (Hb) concentrations were monitored weekly. Feed intakes were measured daily. Hemoglobin repletion efficiency (HRE) was calculated as the gain in total body hemoglobin Fe (Hb-Fe) divided by Fe intake. Hb concentrations, Hb-Fe gains, and HRE were not different between the groups at any time point ( p > 0.05). HRE values in the red bean group were 50% in the first week and 30% over the entire 4 week period. In the white bean group, they were 56 and 26%, respectively. Proline-rich protein mRNA concentrations in parotid glands were higher in the red bean group compared to the white bean group. These results show that iron bioavailabilities from red and white beans are similar and suggest that pigs adapt to the inhibitory effects of polyphenols on iron absorption by increasing the secretion of protective proline-rich proteins in the saliva.  相似文献   

Planktivorous vendace (Coregonus albula) utilise algae‐derived fatty acids for biomass increase and lipid deposition          下载免费PDF全文

Ursula Strandberg  Minna Hiltunen  Sami J. Taipale  Sean Yeung  Paula Kankaala 《Ecology of Freshwater Fish》2018,27(2):533-541

Spatial and seasonal variation in the abundance and composition of phytoplankton and other basal resources (bacteria, terrestrial detritus) influence the availability of essential polyunsaturated fatty acids (PUFA) for upper trophic levels in lake food webs. We studied accumulation, composition and content of fatty acids in planktivorous vendace (Coregonus albula) muscle tissue during the summer feeding period (May to late September) in six boreal lakes. Vendace muscle fatty acid content increased from ~17.7 mg/g DW to ~28.1 mg/g DW from spring to summer, corresponding to a ~59% increase in total fatty acids. PUFA accounted for 45%–65% of all fatty acids, and the most abundant fatty acid was docosahexaenoic acid (DHA, 22:6n‐3). The DHA content remained relatively constant throughout the sampling period (~7–8 mg/g DW), but the proportion of DHA decreased from ~40% in spring to ~30% in summer and autumn. The decrease in DHA proportion was due to accumulation of other fatty acids, primarily C₁₈ PUFA (predominantly synthetised by algae) and monounsaturated fatty acids. A similar fatty acid accumulation pattern was observed in lipid storing copepods, an important prey for planktivorous vendace. The abundance of bacterial and terrestrial biomarker fatty acids in vendace muscle and prey items was low (<5% and <0.1% respectively). The increase in weight and the deposition of internal energy stores in vendace were achieved predominantly by algae‐based food chain. This has ecological implications, as vendace requires sufficient lipid stores for reproduction in autumn and survival over winter.  相似文献   

Effects of Glucose Concentration on in vitro Fertilization in BALB/c Mice     

HT Wu  CK Chou  CS Lin  MC Huang 《Reproduction in domestic animals》2003,38(6):470-474

BALB/c mice are widely used in genetic, tumour and immunological studies. However, the mice demonstrate a lower reproduction rate, low fertility and small litters, because of their highly genetic homozygoisty. Based on in vitro fertilization (IVF), a routine technique for biomedical studies, it is worth to evaluate the effects to BALB/c mice on IVF efficiency. In order to test the genetic factor affecting the IVF efficiency of BALB/c, four reciprocal IVF tests of BALB/cByJ and FVB/NCrl mice were performed. The results showed that the average fertility of IVF sponsored by FVB/NCrl spermatozoa was 69.6%, but only 12.1% was obtained from BALB/cByJ strain. Effect of glucose contained in the culture medium to the IVF efficiency of BALB/cByJ was also evaluated. The results showed that the fertility of BALB/cByJ spermatozoa incubated with 0, 2.7, 5.5, 11.1 and 22.2 mm of glucose in the TYH medium were 6.8, 9.9, 13.9, 32.7 and 22.2%, respectively. It is showed that IVF efficiency of BALB/cByJ spermatozoa could be improved depending on the concentration of glucose in the IVF medium. According to the results, it is beleived that lower IVF of BALB/cByJ mice might be due to the genetic defect in spermatozoa and increasing glucose in the IVF medium which significantly affect the IVF efficiency of BALB/cByl via activating the spermatozoa.  相似文献   

Membrane phosphatidylserine regulates surface charge and protein localization   总被引：1，自引：0，他引：1  

Yeung T  Gilbert GE  Shi J  Silvius J  Kapus A  Grinstein S 《Science (New York, N.Y.)》2008,319(5860):210-213

Electrostatic interactions with negatively charged membranes contribute to the subcellular targeting of proteins with polybasic clusters or cationic domains. Although the anionic phospholipid phosphatidylserine is comparatively abundant, its contribution to the surface charge of individual cellular membranes is unknown, partly because of the lack of reagents to analyze its distribution in intact cells. We developed a biosensor to study the subcellular distribution of phosphatidylserine and found that it binds the cytosolic leaflets of the plasma membrane, as well as endosomes and lysosomes. The negative charge associated with the presence of phosphatidylserine directed proteins with moderately positive charge to the endocytic pathway. More strongly cationic proteins, normally associated with the plasma membrane, relocalized to endocytic compartments when the plasma membrane surface charge decreased on calcium influx.  相似文献