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Timmie Topoleski - One of the best experts on this subject based on the ideXlab platform.
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Viscous Behavior of Different Concentrations of Bovine Calf Serum Used to Lubricate the Micro-textured CoCrMo Alloy Material before and after Wear Testing
IFMBE Proceedings, 2010Co-Authors: Geriel Ettienne-modeste, Timmie TopoleskiAbstract:Bovine Calf Serum is a common lubricant used to test the rheological properties of synovial fluid; however the rheological properties of the Serum and their effect on testing the wear behavior of artificial joints are not fully understood. Bovine Calf Serum (BCS) is used as a model lubricant for testing artificial joints because the natural human synovial fluid is not readily available. Synovial fluid is the lubricant for joints and the source of nutrition for articular cartilage. The purpose of the present paper is to provide a comprehensive examination of the flow properties of bovine Calf Serum, with and without antibacterial agents, to determine whether it can be used as appropriate model for synovial fluid when testing the wear of artificial joint materials. We hypothesized that the viscosity of a mixture of bovine Calf Serum and water changes as the concentration of bovine Calf Serum changes before and after wear testing the lubricants. The steady-shear viscosity and storage and loss moduli were evaluated in BCS from fifteen lubricant compositions, with and without antibacterial agents, before and after wear testing the lubricant. The steady-shear viscosity varied over two orders of magnitude for both lubricants samples with and without antibacterial agent, with a greater variation for the samples with antibacterial agents. Bovine Calf Serum without antibacterial agents was more likely to exhibit normal viscous properties than bovine Calf Serum with antibacterial agents (p
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viscous behavior of different concentrations of bovine Calf Serum used to lubricate the micro textured cocrmo alloy material before and after wear testing
2010Co-Authors: Geriel Ettiennemodeste, Timmie TopoleskiAbstract:Bovine Calf Serum is a common lubricant used to test the rheological properties of synovial fluid; however the rheological properties of the Serum and their effect on testing the wear behavior of artificial joints are not fully understood. Bovine Calf Serum (BCS) is used as a model lubricant for testing artificial joints because the natural human synovial fluid is not readily available. Synovial fluid is the lubricant for joints and the source of nutrition for articular cartilage. The purpose of the present paper is to provide a comprehensive examination of the flow properties of bovine Calf Serum, with and without antibacterial agents, to determine whether it can be used as appropriate model for synovial fluid when testing the wear of artificial joint materials. We hypothesized that the viscosity of a mixture of bovine Calf Serum and water changes as the concentration of bovine Calf Serum changes before and after wear testing the lubricants. The steady-shear viscosity and storage and loss moduli were evaluated in BCS from fifteen lubricant compositions, with and without antibacterial agents, before and after wear testing the lubricant. The steady-shear viscosity varied over two orders of magnitude for both lubricants samples with and without antibacterial agent, with a greater variation for the samples with antibacterial agents. Bovine Calf Serum without antibacterial agents was more likely to exhibit normal viscous properties than bovine Calf Serum with antibacterial agents (p <0.001). The non-worn “before wear” BCS lubricants were less viscous than the worn “after wear” lubricants. Other parameters distinguished the two groups, and showed statistical significance. Both groups exhibited degenerate flow properties when compared to the synovial fluid from healthy individuals. Further examination of the connection between flow properties of BCS, other joint fluids commonly used to test artificial joints and the tribology of joint replacement prostheses should be studied.
Julia F Ridpath - One of the best experts on this subject based on the ideXlab platform.
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Virus and Antibodies against Bovine Viral Diarrhea Virus Methods for Detection and Frequency of Contamination of Fetal Calf Serum with Bovine Viral Diarrhea
2013Co-Authors: Steven R Bolin, Peter J Matthews, Julia F RidpathAbstract:Methods used by the National Animal Disease Center to test fetal Calf Serum for contamination with bovine viral diarrhea virus (BVDV) and antibodies against BVDV are described. Using those methods, virus was isolated from 332 of 1,608 (20.6%) lots of raw fetal Calf Serum obtained specifically for the Center and 93 of 190 (49%) lots of commercially available fetal Calf Serum. Virus neutralization and immunoperoxidase staining tests were used to detect antibodies against BVDV in 224 of the 1,608 (13.9%) lots of raw fetal Calf Serum. Both BVDV and antibodies against BVDV were detected in 50 lots of raw Serum. The molecular specificity of antibodies against BVDV was determined by radioimmunoprecipitation. Lots of fetal Calf Serum that contained BVDV-specific antibodies that did not neutralize virus were identified. The bovine viral diarrhea virus (BVDV) is ubiquitous in cattle and exists as either of 2 biotypes, noncytopathic or cytopathic, that are differentiated by cytopathic effect in cell culture. The developing bovine fetus is readily infected by BVDV, which replicates in several fetal cell types. 10,11,25,27 Cell cultures established from infected fetuses are often infected with BVDV when initiated and remain so indefinitely. Because noncytopathic BVDV does not induce a cytopathic effect, infection of cell cultures may not be detected unless the cultures are tested by immunocytochemical procedures. In addition to infecting several fetal cell types, BVDV is found cell-free in fetal Calf secreating a potential problem for diagnostic laboratories because fetal Calf Serum is frequently used to supplement media used for cell culture, and a variety of cell cultures from several species are susceptible to infection with BVDV. 12,24 An undetected BVDV infection of cell cultures may complicate laboratory diagnosis of disease. In addition to BVDV, fetal Calf Serum may contain antibodies against BVDV. 13,15,29 Those antibodies may interfere with isolation of BVDV from tissues of infected cattle or lead to false positive results in serologic or immunocytochemical tests for BVDV. The titer of stock BVDV propagated for use in diagnostic tests may be reduced by antibodies in fetal Calf Serum. Also, antibodies against BVDV cross-react with other pestiviruses, namely border disease virus of sheep and hog cholera virus of swine, and may interfere with diagnosis of diseases caused by those viruses. From the Virology Cattle Research Unit (Bolin, Ridpath) and Scientific Services (Matthews), National Animal Disease Center, USDA, Agricultural Research Service, PO Box 70, Ames, IA 50010. Received for publication September 24, 1990. This report describes methods currently in use at the National Animal Disease Center (NADC) to test fetal Calf Serum for BVDV and antibodies against BVDV. The frequencies of isolation of BVDV and detection of antibodies against BVDV in 1,608 lots of raw fetal Calf Serum obtained for the NADC and the frequency of isolation of BVDV from 190 lots of commercially available fetal Calf Serum are also reported. Materials and methods Fetal Calf Serum. Fetal Calf Serum was obtained for the NADC from 5 abattoirs over a period of 18 mo by a commercial supplier of raw Serum. The abattoirs were located in South Dakota, Minnesota, and Illinois. Two of the abattoirs processed dairy cattle or beef heifers, exclusively. The other 3 abattoirs processed both beef and dairy cattle. Records that identified source of the fetal Calf Serum (dam of fetus and farm of origin) were not available. Serum from 2 or 3 fetuses was pooled by the supplier forming 1,608 lots of 1 liter each. Also, 190 lots of commercially available processed fetal Calf Serum were submitted to the NADC by various federal agencies over a 7-yr period for testing for adventitious virus. The number of fetuses represented and volume of those lots of commercially available Serum were not known. There were 20 distributors of fetal Calf Serum represented in those submissions. Virus isolation. A 50-ml sample from each liter of unprocessed pooled fetal Calf Serum was centrifuged at 15,000 x g for 1 hr, passaged through a 0.22-μm filter, mixed 1:1 with Eagle’s minimum essential medium (MEM), and inoculated onto bovine turbinate (BT) cells grown in a 490cm roller bottle. After 14 days of incubation at 37 C, the roller bottle, containing medium and cells, was frozen and thawed. A 0.1-ml aliquot of the thawed contents of the roller bottle was inoculated onto BT cells grown on multichamber glass slides. After 48 hr of incubation at 37 C in a humidified atmosphere containing 5% CO2, the BT cells were fixed in 199 200 Bolin, Matthews, Ridpath acetone and tested for viral antigen by direct fluorescent antibody staining procedures. Commercially available processed fetal Calf Serum was similarly tested, except 850-cm roller bottles were used and the inoculum was increased to 100 ml of Serum mixed with an equal volume of medium. ‘Virus neutralization. A standard microtitration procedure for virus neutralization was used. Serial 2-fold dilutions through the 1:8 dilution of Serum were made in MEM. The dilutions of Serum were mixed with approximately 50 cell culture infective doses of the cytopathic BVDV-Singer isolate and incubated at 37 C in a humidified atmosphere of 5% CO,. After 1 hr, BT cells were added to mixtures of fetal Calf Serum and virus. After 96 hr, end points of antibody concentration were determined by microscopic examination of BT cells for cytopathic effect induced by BVDV-Singer. Some lots of Serum that had titers of virus neutralizing antibodies of ≥ 8 were further tested through the 1:256 dilution of Serum. Immunoperoxidase staining. An immunoperoxidase staining procedure for detection of porcine antibodies to pestiviruses was modified for use with fetal Calf Serum.1 Microtitration plate wells were seeded with BT cells and incubated at 37 C in a humidified 5% CO2 atmosphere. After 24 hr, BT cells in every other microtitration plate well were inoculated with approximately 1,000 infective doses of BVDVSinger. The BT cells in the remaining microtitration plate wells served as noninfected controls for nonspecific background staining. After a 24-hr incubation with virus, the microtitration plates were drained, rinsed twice with phosphate-buffered saline (PBS, pH 7.6), and fixed for 10 min at room temperature with 35% acetone in PBS containing 0.02% bovine Serum albumin. The microtitration plates were then dried for 25 min at 37 C. A mixture of 50 μ1 of fetal Calf Serum and 50 μ1 of binding buffer (PBS containing 0.05% Tween 20 and 2.95% NaCl) was inoculated onto infected and noninfected cells. After 30 min incubation at room temperature, the microtitration plates were drained and washed 3 times for 2 min with wash buffer (PBS containing 0.05% Tween 20). Peroxidase-conjugated recombinant protein G was diluted 1: 1,000 in binding buffer, and 50 μ1 of the resulting solution was added to each microtitration plate well for a 15-min incubation at room temperature. The microtitration plates were then drained and washed 2 times for 1 min each with wash buffer. Fresh substrate solution (100 μl per well) was prepared by slowly adding 10 mg of 3-amino9-ethylcarbazole dissolved in 3 ml N,N-dimethyl-formamide to 50 ml of 0.05 M sodium acetate buffer (pH 5.0) containing 0.2 ml of 3% hydrogen peroxide. After 1 hr, the enzymatic reaction was stopped by rinsing the microtitration plates with tap water. Radioimmunoprecipitation. Radiolabeled virus-induced polypeptides were immunoprecipitated with selected samples of fetal Calf Serum and analyzed by polyacrylamide gel electrophoresis as described. The sera selected contained antibodies against BVDV-Singer that were detected by both virus neutralization and immunoperoxidase staining, only by virus neutralization, or only by immunoperoxidase staining. Fluorograms were made by exposing dried gels to film for 5 days at -90 C. Designations of virus-induced polypeptides followed those of a previous report? Controls. The BT cells used in this study were tested and found free of adventitious BVDV by direct fluorescent antibody staining, immunoperoxidase staining, and radioimmunoprecipitation procedures. The fetal Calf Serum that supplemented the MEM used to grow BT cells was tested and found free of adventitious BVDV and antibodies against BVDV by the methods described here.
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methods for detection and frequency of contamination of fetal Calf Serum with bovine viral diarrhea virus and antibodies against bovine viral diarrhea virus
Journal of Veterinary Diagnostic Investigation, 1991Co-Authors: Steven R Bolin, Peter J Matthews, Julia F RidpathAbstract:Methods used by the National Animal Disease Center to test fetal Calf Serum for contamination with bovine viral diarrhea virus (BVDV) and antibodies against BVDV are described. Using those methods, virus was isolated from 332 of 1,608 (20.6%) lots of raw fetal Calf Serum obtained specifically for the Center and 93 of 190 (49%) lots of commercially available fetal Calf Serum. Virus neutralization and immunoperoxidase staining tests were used to detect antibodies against BVDV in 224 of the 1,608 (13.9%) lots of raw fetal Calf Serum. Both BVDV and antibodies against BVDV were detected in 50 lots of raw Serum. The molecular specificity of antibodies against BVDV was determined by radioimmunoprecipitation. Lots of fetal Calf Serum that contained BVDV-specific antibodies that did not neutralize virus were identified.
C. J. A. Sol - One of the best experts on this subject based on the ideXlab platform.
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Frequent detection of bovine polyomavirus in commercial batches of Calf Serum by using the polymerase chain reaction
Journal of General Virology, 1991Co-Authors: R. Schuurman, Bert Van Steenis, A. Van Strien, J. Van Der Noordaa, C. J. A. SolAbstract:Twenty commercial batches of Calf Serum, obtained from several suppliers, were tested for the presence of bovine polyomavirus (BPyV) DNA and antibodies against the virus. Using polymerase chain reaction (PCR) technology, BPyV DNA was detected in 70% of the batches; no BPyV was detected in any of the negative control samples. The specificity of the amplification reactions was proven by hybridization. PCR results were confirmed by virus isolation experiments performed with five PCR-positive and five PCR-negative Serum batches. The results indicate that the use of Calf Serum to supplement tissue culture media involves a serious risk of contaminating cell cultures with BPyV. No correlation was observed between the presence or absence of anti-BPyV immunoglobulins and the detection of BPyV-specific DNA sequences in the Serum batches.
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Bovine polyomavirus, a frequent contaminant of Calf Serum
Biologicals : journal of the International Association of Biological Standardization, 1991Co-Authors: R. Schuurman, Bert Van Steenis, C. J. A. SolAbstract:Bovine polyomavirus (BPyV) belongs to the family of the polyomaviruses which, together with the papillomavwus family, forms the genus of the papovaviridue. Bovine polyomaviruses have been molated fi'om monkey kidney cell cultures by several laboratories. The wrus most probably infected the cells through the use of tissue culture medium that was supplemented with a BPyV-contaminated batch of Calf Serum In general, depending on whether permisswe or non-permisswe cells are infected, polyomawrus infectmns proceed in two different ways.
Steven R Bolin - One of the best experts on this subject based on the ideXlab platform.
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Virus and Antibodies against Bovine Viral Diarrhea Virus Methods for Detection and Frequency of Contamination of Fetal Calf Serum with Bovine Viral Diarrhea
2013Co-Authors: Steven R Bolin, Peter J Matthews, Julia F RidpathAbstract:Methods used by the National Animal Disease Center to test fetal Calf Serum for contamination with bovine viral diarrhea virus (BVDV) and antibodies against BVDV are described. Using those methods, virus was isolated from 332 of 1,608 (20.6%) lots of raw fetal Calf Serum obtained specifically for the Center and 93 of 190 (49%) lots of commercially available fetal Calf Serum. Virus neutralization and immunoperoxidase staining tests were used to detect antibodies against BVDV in 224 of the 1,608 (13.9%) lots of raw fetal Calf Serum. Both BVDV and antibodies against BVDV were detected in 50 lots of raw Serum. The molecular specificity of antibodies against BVDV was determined by radioimmunoprecipitation. Lots of fetal Calf Serum that contained BVDV-specific antibodies that did not neutralize virus were identified. The bovine viral diarrhea virus (BVDV) is ubiquitous in cattle and exists as either of 2 biotypes, noncytopathic or cytopathic, that are differentiated by cytopathic effect in cell culture. The developing bovine fetus is readily infected by BVDV, which replicates in several fetal cell types. 10,11,25,27 Cell cultures established from infected fetuses are often infected with BVDV when initiated and remain so indefinitely. Because noncytopathic BVDV does not induce a cytopathic effect, infection of cell cultures may not be detected unless the cultures are tested by immunocytochemical procedures. In addition to infecting several fetal cell types, BVDV is found cell-free in fetal Calf secreating a potential problem for diagnostic laboratories because fetal Calf Serum is frequently used to supplement media used for cell culture, and a variety of cell cultures from several species are susceptible to infection with BVDV. 12,24 An undetected BVDV infection of cell cultures may complicate laboratory diagnosis of disease. In addition to BVDV, fetal Calf Serum may contain antibodies against BVDV. 13,15,29 Those antibodies may interfere with isolation of BVDV from tissues of infected cattle or lead to false positive results in serologic or immunocytochemical tests for BVDV. The titer of stock BVDV propagated for use in diagnostic tests may be reduced by antibodies in fetal Calf Serum. Also, antibodies against BVDV cross-react with other pestiviruses, namely border disease virus of sheep and hog cholera virus of swine, and may interfere with diagnosis of diseases caused by those viruses. From the Virology Cattle Research Unit (Bolin, Ridpath) and Scientific Services (Matthews), National Animal Disease Center, USDA, Agricultural Research Service, PO Box 70, Ames, IA 50010. Received for publication September 24, 1990. This report describes methods currently in use at the National Animal Disease Center (NADC) to test fetal Calf Serum for BVDV and antibodies against BVDV. The frequencies of isolation of BVDV and detection of antibodies against BVDV in 1,608 lots of raw fetal Calf Serum obtained for the NADC and the frequency of isolation of BVDV from 190 lots of commercially available fetal Calf Serum are also reported. Materials and methods Fetal Calf Serum. Fetal Calf Serum was obtained for the NADC from 5 abattoirs over a period of 18 mo by a commercial supplier of raw Serum. The abattoirs were located in South Dakota, Minnesota, and Illinois. Two of the abattoirs processed dairy cattle or beef heifers, exclusively. The other 3 abattoirs processed both beef and dairy cattle. Records that identified source of the fetal Calf Serum (dam of fetus and farm of origin) were not available. Serum from 2 or 3 fetuses was pooled by the supplier forming 1,608 lots of 1 liter each. Also, 190 lots of commercially available processed fetal Calf Serum were submitted to the NADC by various federal agencies over a 7-yr period for testing for adventitious virus. The number of fetuses represented and volume of those lots of commercially available Serum were not known. There were 20 distributors of fetal Calf Serum represented in those submissions. Virus isolation. A 50-ml sample from each liter of unprocessed pooled fetal Calf Serum was centrifuged at 15,000 x g for 1 hr, passaged through a 0.22-μm filter, mixed 1:1 with Eagle’s minimum essential medium (MEM), and inoculated onto bovine turbinate (BT) cells grown in a 490cm roller bottle. After 14 days of incubation at 37 C, the roller bottle, containing medium and cells, was frozen and thawed. A 0.1-ml aliquot of the thawed contents of the roller bottle was inoculated onto BT cells grown on multichamber glass slides. After 48 hr of incubation at 37 C in a humidified atmosphere containing 5% CO2, the BT cells were fixed in 199 200 Bolin, Matthews, Ridpath acetone and tested for viral antigen by direct fluorescent antibody staining procedures. Commercially available processed fetal Calf Serum was similarly tested, except 850-cm roller bottles were used and the inoculum was increased to 100 ml of Serum mixed with an equal volume of medium. ‘Virus neutralization. A standard microtitration procedure for virus neutralization was used. Serial 2-fold dilutions through the 1:8 dilution of Serum were made in MEM. The dilutions of Serum were mixed with approximately 50 cell culture infective doses of the cytopathic BVDV-Singer isolate and incubated at 37 C in a humidified atmosphere of 5% CO,. After 1 hr, BT cells were added to mixtures of fetal Calf Serum and virus. After 96 hr, end points of antibody concentration were determined by microscopic examination of BT cells for cytopathic effect induced by BVDV-Singer. Some lots of Serum that had titers of virus neutralizing antibodies of ≥ 8 were further tested through the 1:256 dilution of Serum. Immunoperoxidase staining. An immunoperoxidase staining procedure for detection of porcine antibodies to pestiviruses was modified for use with fetal Calf Serum.1 Microtitration plate wells were seeded with BT cells and incubated at 37 C in a humidified 5% CO2 atmosphere. After 24 hr, BT cells in every other microtitration plate well were inoculated with approximately 1,000 infective doses of BVDVSinger. The BT cells in the remaining microtitration plate wells served as noninfected controls for nonspecific background staining. After a 24-hr incubation with virus, the microtitration plates were drained, rinsed twice with phosphate-buffered saline (PBS, pH 7.6), and fixed for 10 min at room temperature with 35% acetone in PBS containing 0.02% bovine Serum albumin. The microtitration plates were then dried for 25 min at 37 C. A mixture of 50 μ1 of fetal Calf Serum and 50 μ1 of binding buffer (PBS containing 0.05% Tween 20 and 2.95% NaCl) was inoculated onto infected and noninfected cells. After 30 min incubation at room temperature, the microtitration plates were drained and washed 3 times for 2 min with wash buffer (PBS containing 0.05% Tween 20). Peroxidase-conjugated recombinant protein G was diluted 1: 1,000 in binding buffer, and 50 μ1 of the resulting solution was added to each microtitration plate well for a 15-min incubation at room temperature. The microtitration plates were then drained and washed 2 times for 1 min each with wash buffer. Fresh substrate solution (100 μl per well) was prepared by slowly adding 10 mg of 3-amino9-ethylcarbazole dissolved in 3 ml N,N-dimethyl-formamide to 50 ml of 0.05 M sodium acetate buffer (pH 5.0) containing 0.2 ml of 3% hydrogen peroxide. After 1 hr, the enzymatic reaction was stopped by rinsing the microtitration plates with tap water. Radioimmunoprecipitation. Radiolabeled virus-induced polypeptides were immunoprecipitated with selected samples of fetal Calf Serum and analyzed by polyacrylamide gel electrophoresis as described. The sera selected contained antibodies against BVDV-Singer that were detected by both virus neutralization and immunoperoxidase staining, only by virus neutralization, or only by immunoperoxidase staining. Fluorograms were made by exposing dried gels to film for 5 days at -90 C. Designations of virus-induced polypeptides followed those of a previous report? Controls. The BT cells used in this study were tested and found free of adventitious BVDV by direct fluorescent antibody staining, immunoperoxidase staining, and radioimmunoprecipitation procedures. The fetal Calf Serum that supplemented the MEM used to grow BT cells was tested and found free of adventitious BVDV and antibodies against BVDV by the methods described here.
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methods for detection and frequency of contamination of fetal Calf Serum with bovine viral diarrhea virus and antibodies against bovine viral diarrhea virus
Journal of Veterinary Diagnostic Investigation, 1991Co-Authors: Steven R Bolin, Peter J Matthews, Julia F RidpathAbstract:Methods used by the National Animal Disease Center to test fetal Calf Serum for contamination with bovine viral diarrhea virus (BVDV) and antibodies against BVDV are described. Using those methods, virus was isolated from 332 of 1,608 (20.6%) lots of raw fetal Calf Serum obtained specifically for the Center and 93 of 190 (49%) lots of commercially available fetal Calf Serum. Virus neutralization and immunoperoxidase staining tests were used to detect antibodies against BVDV in 224 of the 1,608 (13.9%) lots of raw fetal Calf Serum. Both BVDV and antibodies against BVDV were detected in 50 lots of raw Serum. The molecular specificity of antibodies against BVDV was determined by radioimmunoprecipitation. Lots of fetal Calf Serum that contained BVDV-specific antibodies that did not neutralize virus were identified.
Toru Kita - One of the best experts on this subject based on the ideXlab platform.
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serofendic acid a novel substance extracted from fetal Calf Serum protects against oxidative stress in neonatal rat cardiac myocytes
Journal of the American College of Cardiology, 2006Co-Authors: Toshihiro Takeda, Masaharu Akao, Madoka Matsumotoida, Masashi Kato, Hiroyuki Takenaka, Yasuki Kihara, Toshiaki Kume, Akinori Akaike, Toru KitaAbstract:Serofendic Acid, a Novel Substance Extracted From Fetal Calf Serum, Protects Against Oxidative Stress in Neonatal Rat Cardiac MyocytesToshihiro Takeda, Masaharu Akao, Madoka Matsumoto-Ida, Masashi ...
