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Science China(Life Sciences) 1996年第6期39卷 592-599页

作者：劳为德刘伟成国祥徐少甫成勇 Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China Jiangsu Agricultural College Yangzhou University Yangzhou 225001 China

Two αs1-casein/chloramphenicol acetyltransferase (CAT) gene constructs overlapping by 3.0kb were constructed and co-injected into murine zygotes. In 9 of 10 lines of transgenic mice obtained, based on analysis of structure and expression of the transgene, accurate extrachromosomal homologous recombination (ECR) between the two overlapping DNA fragments was found. Different levels of CAT activity were detected in milk from these lines. The highest CAT activity was about 25-50μg/mL milk. In some mice. CAT activity was found in salvia gland, thymus and spleen extracts. The high frequency and accuracy of ECR reported here will be applicable in the experimental manipulation for generation of relatively large transgene.

关键词： extrachromosomal homologous recombination bovine a si-casein gene chloramphenicol acetyltransferase transgenic mice mammary gland.

Evaluation of an internal control in a multiplex-PCR assay for sex determination of <i>in vitro</i>-produced bovine embryos

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Advances in Bioscience and Biotechnology 2011年第6期2卷 456-462页

作者： Fabiana de Almeida Rufino Marcelo Marcondes Seneda Alice Fernandes Alfieri Katia Cristina Silva-Santos Karina Cristina Puggesi Rubin Amauri Alcindo Alfieri 不详

The use of an internal control in a multiplex-PCR assay for sex determination of In Vitro-produced bovine embryos was evaluated in biopsies of groups of 54 fresh and 44 frozen embryos. The internal controls used were the primers BOV 1 and BOV 2, which amplify a product with 626 base pairs (bp) of bovine mitochondrial DNA ND5 gene. The primers BRY.4aF and BRY.4aR were used for bovine Y chromosome sequence amplification. The specificity of multiplex- PCR reactions realized in biopsies corresponding to about 20% of each fresh embryo (10 male and 10 female) by means of confirming the sexing in the remaining embryo content (~80%) presented 100% specificity. Amplicons of the internal control and Y chromosome were both amplified until dilution corresponding to 6.25% of total extracted DNA from a male embryo. Sex determination was possible in 53 (98.1%) fresh embryos and 40 (90.9%) frozen embryos. The products related to the Y chromosome and mitochondrial DNA were simultaneously amplified in 34 (63%) fresh embryos and 27 (61.4%) frozen embryos, showing a male embryo. The female sex, distinguished by internal control amplification only, was detected in 19 (35.2%) and 13 (29.5%) biopsies, respectively, of fresh and frozen embryos. In one (1.8%) and four (9.1%) biopsies of fresh and frozen embryos, respectively, neither product was amplified, most likely due to the absence of embryonic cells or the presence of embryonic cells going through apoptosis. The multiplex-PCR assay developed in this work showed avoided the limitation of a lack of an internal standard, and was also sensitive, specific, and efficient in reaction failure identification. This technique shows great potential for use on a commercial scale in routine sex determination of In Vitro-produced embryos.

关键词： bovine Embryos In Vitro Production Sexing Multiplex-PCR

Comparison Between Conventional Convective Heating and Microwave Heating: An FTIR Spectroscopy Study of the Effects of Microwave Oven Cooking of bovine Breast Meat

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Journal of Electromagnetic Analysis and Applications 2012年第11期4卷 433-439页

作者： Emanuele Calabrò Salvatore Magazù Department of Physics University of Messina Messina Italy.

The effects of microwave energy and conventional convective heating on bovine meat were studied in the mid-infrared region by FTIR spectroscopy, to highlight the differences between the two cooking methods. Samples of 100 g of bovine breast meat were cooked using three treatments: heating in a conventional electric oven at the temperature of 165°C for 16 min, heating in a microwave oven at 800 W for 95 sec, and heating in the same microwave oven at 650 W for 160 sec. Significant decreases in intensity of vibration bands of CH2 methylene group at 1921 and 1853 cm-1 and of the carbonyl band at 1742 cm-1 were observed after microwave heating with respect to heating in a conventional oven, showing that Maillard reaction occurs partially using microwave oven. Spectral analysis in the amide I region after microwave cooking at 800 W for 95 sec showed that an increase in intensity occurred in the region from 1665 to 1690 cm-1 which can be attributed to β-turns, characteristic of disorder processes in the protein. Further analysis after microwave cooking at 650 W for 160 sec evidenced major increase in intensity of β-turns content and the appearance of significant increases of β-sheet component at 1635 cm-1 and 1695 cm-1 that can be attributed to aggregated β-sheets structures.

关键词： Convective heating Microwave oven FTIR spectroscopy Amide I region bovine breast meat

Binding of naturally occurring hydroxycinnamic acids to bovine serum albumin

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Natural Science 2010年第6期2卷 563-570页

作者： Lucie Trnkova Iva Bousova Vladimir Kubicek Jaroslav Drsata Charles University in Prague Faculty of Pharmacy Hradec Králové Czech Republic Charles University in Prague Faculty of Pharmacy Hradec Králové Czech Republic University of Hradec Králové Faculty of Education Hradec Králové Czech Republic

Hydroxycinnamic acids (HCAs) possess numer- ous biological effects including antioxidant, antiallergic, antimicrobial, and immunomodulatory activities and due to these properties are widely used in folk medicine. Nevertheless, they can interact with protein molecules and cause some structural and functional changes. The possib- ility of HCAs binding to bovine serum albumin (BSA) under physiological conditions was inve- stigated by the UV-VIS absorption spectroscopy and fluorescence quenching method. Apart from rosmarinic acid, all tested HCAs quenched tryptophan fluorescence of BSA in the studied range of concentrations (0-20 μM) mainly by static quenching mechanism (formation of non- fluorescent HCA-BSA complexes). The binding constants, number of binding sites and free energy changes were determined. The binding affinities of HCAs were ranked in the order: chlorogenic acid > sinapic acid ≥ caffeic acid > ferulic acid > o-coumaric acid > p-coumaric acid ≥ m-coumaric acid, which was confirmed by spectral overlaps of BSA emission spectrum with absorption spectrum of HCA. All free energy changes possessed negative sign indicating the spontaneity of HCA-BSA interaction.

关键词： bovine Serum Albumin Hydroxycinnamic Acid Fluorescence Quenching Protein-Ligand Binding

Isotropic shear bond strength behavior of superficial bovine dentin: A pilot study

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Open Journal of Stomatology 2013年第1期3卷 1-7页

作者： Camila Sabatini Sebastiano Andreana Department of Restorative Dentistry School of Dental Medicine State University of New York Buffalo USA

The aim of this pilot study was to evaluate the shear bond strength of superficial bovine incisor dentin in different crown regions. Bonding was performed to the incisal, middle and cervical thirds of superficial bovine coronal dentin (n = 20) with a two-step etch-and-rinse adhesive (Optibond Solo Plus) and resin composite (Z100). Shear bond strength was evaluated at 24 h and failure modes of representative specimens wereobserved with FE-SEM. Non-parametric Kruskal-Wallis test with a significance level of 0.05 was used for data analysis. Mean shear bond strength values for the incisal, middle, and cervical thirds were 36.9 (3.1), 42.6 (2.6), and 37.1 (2.1) respectively with no significant differences evidenced between the crown thirds (p = 0.19). Observation of the failure mode of representative specimens demonstrated that specimens with high bond strength values exhibited predominantly mixed-type failures whereas low strength specimens exhibited adhesive failures between the dentin and adhesive. The absence of significant differences in shear bond strength between crown thirds indicate that, regardless of tubule orientation, any crown region can be used when superficial bovine incisor dentin is used for shear bond strength testing.

关键词： Adhesion Shear Bond Strength bovine Dentin Isotropic Properties Failure Mode

Association between microsatellite markers and bovine tuberculosis in Chadian Zebu cattle

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Open Journal of Animal Sciences 2013年第1期3卷 27-35页

作者： Abdirahman A. Ali Peter C. Thomson Haja N. Kadarmideen Division of Genetics and Bioinformatics Department of Veterinary Clinical and Animal Sciences Faculty of Health and Medical Sciences University of Copenhagen Frederiksberg Denmark ReproGen—Animal Bioscience Group Faculty of Veterinary Science University of Sydney Sydney Australia

bovine tuberculosis (BTB) is a considerable threat to livestock keepers and public health in many developing and underdeveloped countries. We investigated associations between 20 microsatellite markers and three phenotypes for BTB in a sample of the Chadian cattle population. The phenotypes measured were: 1) single intra-dermal comparative cervical tuberculin test (SICCT) performed on live animals, 2) presence of lesion post-slaughter, 3) a bacteriological tissue culture test for Mycobacterium bovis using the samples with observed lesions and 4) a predicted Bayesian model (BM) estimate of a true BTB disease status using all tested animals. All traits were recorded in binary form and as either 1 = presence or 0 = absence. A total of 224 animals for SICCT, lesion and BM traits and 96 animals with bacteriological culture test were genotyped. Generalised linear models were fitted to the binary BTB phenotypes that consisted of age (covariate), sex (2 levels), breed (2 levels) and markers (alleles: 5 - 14 levels) as explanatory variables and implemented in R using glm with a logit link function. The model was fitted for each marker, separately. Six out of 20 markers tested were significantly associated with at least one trait considered;these were ILSTS005, ILSTS006, TGLA227, BM2113 and CSRM66. Genomic regions around these markers may serve as a basis for further functional investigations. This is the first study to report association of microsatellite markers with bovine tuberculosis traits in African or Chadian cattle population.

关键词： bovine Tuberculosis Breeding Disease-Resistant Cattle Genetic Markers Mycobaterium bovis African Cattle

Serum-Derived bovine Immunoglobulin/Protein Isolate Therapy for Patients with Refractory Irritable Bowel Syndrome

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Open Journal of Gastroenterology 2014年第10期4卷 329-334页

作者： Leonard B. Weinstock Victoria S. Jasion Specialists in Gastroenterology St. Louis USA Department of Medical Affairs Entera Health Inc. Cary USA

Background: A small double-blind study showed benefits of serum-derived bovine immunoglobulin/protein isolate (SBI), for diarrhea-predominant irritable bowel syndrome (IBS-D) [1]. The purpose of this chart review was to assess safety and clinical outcomes of SBI in refractory irritable bowel syndrome (IBS) patients. Methods: A retrospective review of 35 IBS patients with diarrhea or mixed diarrhea/constipation pattern (IBS-M) who were administered SBI 5 grams twice daily was performed. Clinical response (“good response” or “no response”) and adverse events were determined by follow-up after four weeks of therapy. Patients were included for evaluation if a lactulose breath test (LBT) had been performed prior to SBI. All patients were refractory to common IBS therapies. The response rate to the inclusion of SBI was calculated in three separate groups: dividing patients based on their LBT results (positive or negative), dividing patients by their IBS diagnosis (IBS-D or IBS-M) and grouping all patients together. Results: Analysis was carried out on 26 IBS-D/-M patients with LBT results. Two patients were lost to follow-up and were excluded from data analysis. The positive LBT group (N = 11) had a 73% (p = 0.117) positive response rate to SBI. The negative LBT group (N = 13) had a significant response rate of 77% (p = 0.040). If patients were divided by IBS diagnosis or grouped together, the response rate to SBI was similarly ranging from 69% - 88%. Adverse events leading to cessation of SBI occurred in 3 of 24 patients. Conclusion: SBI appeared to be a safe and effective nutritional moiety in refractory IBS-D and IBS-M patients. Larger, double-blind studies are needed.

关键词： Irritable Bowel Syndrome (IBS) Small Intestinal Bacterial Overgrowth (SIBO) Serum-Derived bovine Immunoglobulin/Protein Isolate (SBI)

Development and quality of bovine embryos produced in vitro using growth factor supplemented serum-free system

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Open Journal of Animal Sciences 2011年第3期1卷 97-105页

作者： Arindam Dhali Vahida M. Anchamparuthy Steve P. Butler Isis K. Mullarky Ronald E. Pearson Frank C. Gwazdauskas 不详

The influence of a growth factor supplemented serum-free system on the development, gene expression, and cryotolerance of in vitro pro- duced bovine embryos was investigated. To assess the embryo development and gene ex- pression in blastocysts, abattoir-derived oo- cytes (obtained from 3 - 10 or bovine serum (FBS, 4%), epidermal growth factor (EGF, 10 ng/mL), insulin like growth factor-1 (IGF-1, 100 ng/mL), stem cell factor (SCF, 50 ng/mL) or combinations of the growth factors. Expressions of selected gene transcripts were relatively quantified in the d 8 blastocysts. To assess the cryotolerance, d 4 morulae (derived from 3 - 10 mm follicles and cultured with the supplementation of FBS or combinations of the growth factors) were vitri- fied, thawed and cultured (with respective sup- plementations). Total cell number and DNA frag- mentation in blastocysts derived from the vitri- fied morulae were assessed through TUNEL assay. The rate (%) of cleavage, blastocyst and expanded/hatched blastocyst did not differ among the culture medium supplementations within the follicle size of 3 - 10 mm (range 65.1 ± 4.3 - 75.4 ± 3.9;22.4 ± 3.9 - 36.4 ± 3.6;and 11.2 ± 2.9 - 23.3 ± 3.2, respectively) or <3 mm (range 59.3 ± 4.2 - 74.5 ± 3.7;15.0 ± 3.5 - 28.7 ± 4.5;and 9.3 ± 2.8 - 17.3 ± 2.7, respectively). Nevertheless, significantly lower (P < 0.05) cleavage and blastocyst rates with FBS and lower blastocyst rate with SCF supplementations were observed for the oocytes derived from <3 compared to 3 - 10 mm follicles. The expression patterns of BCL-2, BAX, HSP1A1, GJA1 and BIRC5 tran- scripts varied significantly (P < 0.05) in all cases, except for BIRC5 in the blastocysts derived from 3 - 10 mm follicles. Following thaw and culture, the development (%) of vitrified morulae into expanded/hatched blastocysts was lower (P < 0.01) with the supplementation of

关键词： IVF Growth Factors Embryo Development Gene Expression Cryotolerance bovine

Tissue Expression Profiles of 5 Putative Imprinted Genes in bovine Chromosome 29

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Open Journal of Animal Sciences 2016年第4期6卷 289-297页

作者： Oladeji Bamidele Ofelia G. Omitogun Ikhide G. Imumorin Biotechnology Laboratory Department of Animal Sciences Obafemi Awolowo University Ile-Ife Nigeria Animal Genetics and Genomics Laboratory International Programs College of Agriculture and Life Sciences Cornell University Ithaca NY USA

Genomic imprinting is an epigenetic process that regulates gene expression in the mammalian genome. Although there are specific imprinting differences between the mammalian species, cattle present unique opportunity for characterizing imprinted genes because of its sub-species classification. Five putative imprinted genes (TSSC4, CDKN1C, KCNQ1, PHLDA2 and NAP1L4) on bovine chromosome 29 (Bta 29) which had been characterized to have promoter CGI were quantitatively assayed for their relative expression across eight tissues (muscle, brain, liver, kidney, spinal cord, heart, lymph and skin) sampled in Angus cattle. The differential abundance of these genes in muscle and skin tissues of Angus, White Fulani and N’Dama cattle breeds was comparatively analyzed. These three breeds are representative of the Bos taurus and Bos indicus cattle sub-species while the two tissues are selected based on their strategic economic importance in cattle production. All the genes, except TSSC4, were relatively expressed across all the tissues. It was observed that Angus had the highest differential abundance in muscle tissues for TSSC4, PHLDA2 and NAP1L4 while N’Dama and White Fulani were the most abundant for KCNQ1 and NAP1L4 in skin tissues. The study identified marked differences in the expression profiles of the genes in both muscle and skin tissues of the three breeds that were characteristics of their genetics, environment and nutrition.

关键词： Imprinted Genes bovine Angus White Fulani N’Dama

Pressure- and Urea-Induced Denaturation of bovine Serum Albumin: Considerations about Protein Heterogeneity

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Open Journal of Biophysics 2012年第1期2卷 4-14页

作者： Douglas Ricardo Norberto Joelma Mauricio Vieira Ancelmo Rabelo de Souza Jose Ailton Conceicao Bispo Carlos Francisco Sampaio Bonafe 不详

Urea denatures proteins at different concentrations, depending on the experimental conditions and the protein. We in-vestigated the pressure-induced denaturation of bovine serum albumin (BSA) in the presence of subdenaturing concen-trations of urea based on a two-state equilibrium. Pressure-induced denaturation was enhanced at urea concentrations ([U]) of 3.5 M to 8.0 M, with the free energy of denaturation at atmospheric pressure ranging from +5.0 to –2.5 kJ/mol of BSA. The m values appeared to be biphasic, with m1 and m2 of 0.92 and 2.35 kJ mol–1?M–1, respectively. Plots of versus ln[U] yielded values of u, the apparent stoichiometric coefficient, of 1.68 and 6.67 mol of urea/mol of BSA for m1 and m2, respectively. These values were compared with the m and u values of other monomeric proteins reported in or calculated from the literature. The very low values of u systematically observed for proteins were suggestive of heterogeneity in the free energy of denaturation. Thus, a u value of 140 mol of urea/mol of BSA may indicate the existence of a heterogeneous molecular population with respect to the free energy of dena-turation.

关键词： Apparent Stoichiometric Coefficient bovine Serum Albumin High Pressure-Induced Denaturation Protein Heterogeneity Urea-Induced Denaturation