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A serological survey of bovine leukemia virus infection in dairy cattle in the suburban farming area of Japan.
1989
Takeo Sakai | Lee W.C.
A survey on the prevalence and distribution of antibodies to BLV was performed by the agar-gel immunodiffusion test over a period from 1983 to 1985. More than 2,407 serum samples were collected from Holstein cattle raised in the eastern part of Saitama prefecture where suburban dairy farm is operated. The average positive rate of this period was 4.9 %. The rates of reactive samples varied from 2.6 to 9.8 % among the age groups of cattle from younger than one year to 14 years of age. The positive rate increased gradually with age. The positive rates also varied widely from 0 to 21 % among areas surveyed. Furthermore, there were large differences in this rate among farms even in the same area. The results were interpreted and discussed in connection with the enzootic feature of BLV infection.
Afficher plus [+] Moins [-]Studies on toxicity of ochratoxin a to chromosomes of tumor cell-line.
1989
Yoon W.J. | Roh M.H. | Kim K.R.
This study was performed to investigate the toxicity of ochratoxin A (OA) to the chromosomes of K562 tumor cell-line in vitro. Chromosomes of K562 tumor cell-line resulted in pseudotriploidy on the control group. Chromosomes of K562 tumor cell-line treated with OA resulted in heteroploidy compared with the control group. The mean number of chromosomes in the karyotype of the control group (60) were 7 in the A group, 5 in the B group, 20 in the C+X group, 7 in the D group, 9 in the E group, 6 in the F group, and 6 in the G+Y group respectively. Treating with 0.7 micro M OA, the number of chromosomes were increased one in E and F group, two in G+Y group compared with control group. In treated with 1.5 micro M OA, the increasing number of chromosome was one in E and F group. In treated with 3 micro M OA, E and F group was increased one and G+Y group were increased two chromosome in G+Y group was decreased one. K562 tumor cell line treated with OA showed Philadelphia-Chromosome in the long arm of the G group karyotype chromosome. The rate of chromosome aberration in K562 tumor cell-line treated with OA was 77 % in 0.7 micro M OA group, 71 % in 1.5 micro M OA group, 82 % in 3 micro M OA group and 94 % in 6 micro M OA group respectively. The rate of chromosome aberration of K562 tumor cell-line treated with OA was high in the high dose level of OA, and chromosome aberration of K562 tumor cell-line treated with OA showed deletion, minute, dicentric-chromosome and translocation in the long arm of the C-group karyotype. As a result of this study, the toxicity of OA showed deletion, minute, dicentric-chromosome and translocation in the long arm of the C-group karyotype, and then, the toxicity of OA resulted in the damage to RNA and protein synthesis in K562 tumor cell-line, and the C-group karyotype of K562 tumor cell-line was target of the toxicity of OA.
Afficher plus [+] Moins [-]Properties of monoclonal antibodies against Berne virus (Toroviridae). Texte intégral
1989
Kaeffer, Bertrand | van Kooten, P | Ederveen, J | van Eden, W | Horzinek, M C | Department of Infectious Diseases and Immunology ; Universiteit Utrecht / Utrecht University [Utrecht]
International audience | Seven hybridomas that secreted monoclonal antibodies (MAB) against the peplomer protein and one that secreted MAB against the nucleocapsid protein of Berne virus (proposed family Toroviridae) were isolated. All MAB directed against the peplomer protein neutralized virus infectivity and, with the exception of MAB 6A7, inhibited each other's binding in competition assays. Neutralization of Berne virus infectivity was potentiated when some MAB were used in pairs. The antibodies have been used to localize toroviral proteins in infected cells; use of antipeplomer MAB 6B10 yielded a diffuse intracytoplasmic immunofluorescence, whereas the antinucleocapsid MAB 1F1 detected antigen in the intra- and perinuclear compartments. By use of radioimmune precipitation, protein A of Staphylococcus aureus was found to bind directly to the nucleocapsid polypeptide, without the requirement for specific antibody. Using fluorescein isothiocyanate-conjugated protein A, the intranuclear accumulation of the nucleoprotein of Berne virus was confirmed by results of immunofluorescence.
Afficher plus [+] Moins [-]Reference blood chemical values in ostriches (Struthio camelus)
1989
Levy, A. | Perelman, B. | Waner, T. | Van Grevenbroek, M. | Van Creveld, C. | Yagil, R.
Reference blood chemical values were determined for 65 male and 61 female ostriches (Struthio camelus) 1 month to 72 months of age. Plasma values of glucose, total protein, triglycerides, cholesterol, uric acid, urea, bilirubin, creatinine, osmolality, electrolytes, and enzyme activity were determined. In general, differences in various values appeared mainly among age groups and less so between sexes. Older ostriches had lower plasma glucose values and enzyme activity than did younger ostriches. High plasma sodium and chloride concentrations in young ostriches correlated with high plasma osmolalities. Plasma calcium values were lower in laying ostriches. Uric acid concentrations were markedly higher than were urea concentrations in all ostriches.
Afficher plus [+] Moins [-]Effects of distention and neostigmine on jejunal vascular resistance, oxygen uptake, and intraluminal pressure changes in ponies
1989
The influence of distention (high baseline intraluminal pressure) and neostigmine methylsulfate on intestinal vascular resistance, oxygen uptake, and intraluminal pressure changes (rhythmic contractions) was studied in terminal jejunal segments which were perfused at a constant rate, in 16 anesthetized ponies. When baseline intraluminal pressure was increased to 10 mm of Hg, the intestinal vascular resistance and amplitude of rhythmic contractions were increased. Neostigmine induced cyclic increases in amplitude of rhythmic contractions whether intraluminal pressure was 0 or 10 mm of Hg. Neostigmine also increased intestinal oxygen uptake at intraluminal pressures of 0 mm of Hg, but not at 10 mm of Hg, and vascular resistance was not altered at either intraluminal pressure. The results indicate that intestinal hemodynamics are adversely affected by distention. Further, neostigmine did not adversely affect intestinal hemodynamics while increasing rhythmic contractions, suggesting that neostigmine may be useful in the treatment of ileus in equids.
Afficher plus [+] Moins [-]Increased peroxidation of erythrocytes of stress-susceptible pigs: an improved diagnostic test for porcine stress syndrome
1989
When incubated with solutions of hydrogen peroxide, erythrocytes of stress-susceptible pigs produced more by-products of lipid peroxidation (as measured as thiobarbituric acid-reactive substances [TBARS]) than did erythrocytes from stress-resistant pigs. Using this technique, discrimination between the 2 pig types was absolute at hydrogen peroxide concentrations of 0.9 and 1.5%. This was in contrast to other methods of identifying stress-susceptible pigs, such as osmotically induced erythrocyte lysis and the determination of plasma pyruvate kinase and creatine kinase activities, for which considerable overlap of data was observed between pig types. The increased TBARS production by erythrocytes was further evidence for the existence of an antioxidant abnormality in stress-susceptible pigs. However, because there were no discernible differences in the major blood antioxidant-related values between stress-susceptible and stress-resistant pigs, the nature of the defect remains unclear. The production of TBARS by erythrocytes when incubated with hydrogen peroxide provides an improved method for identifying stress-susceptible pigs.
Afficher plus [+] Moins [-]Serum and tissue fluid norfloxacin concentrations after oral administration of the drug to healthy dogs
1989
Norfloxacin, a 4-quinolone antibiotic, was administered orally to 4 healthy dogs at dosages of 11 and 22 mg/kg of body weight, every 12 hours for 4 days, with a 4-week interval between dosing regimens. Serum and tissue cage fluid (TCF) norfloxacin concentrations were measured at 0, 0.5, 1, 1.5, 2, 3, 4, 5, 6, 8, 10, and 12 hours after the first and seventh dose of each dosing regimen. When administered at a dosage of 11 mg/kg, the mean peak serum concentration (Cmax) was 1.0 micrograms/ml at 1 hour, the time of mean peak concentration (Tmax) after the first dose. After the seventh dose, the Cmax was 1.4 micrograms/ml at Tmax of 1.5 hours. The Tmax for the TCF concentration was 5 hours, with Cmax of 0.3 micrograms/ml and 0.7 micrograms/ml after the first and seventh dose, respectively. When administered at a dosage of 22 mg/kg, the serum Tmax was 2 hours after the first dose, with Cmax of 2.8 micrograms/ml. After the seventh dose, the serum Tmax was 1.5 hours, with Cmax of 2.8 micrograms/ml. The Tmax for the TCF concentration was 5 hours after the first and seventh doses, with Cmax of 1.2 micrograms/ml and 1.6 micrograms/ml, respectively. After the seventh dose, the serum elimination half-life was 6.3 hours for a dosage of 11 mg/kg and was 6.7 hours for a dosage of 22 mg/kg. For serum concentration, the area under the curve from 0 to 12 hours (AUC0 leads to 12) was 8.77 micrograms.h/ml and 18.27 micrograms.h/ml for dosages of 11 mg/kg and 22 mg/kg, respectively. The corresponding AUC0 leads to 12 for the TCF concentration was 6.20 micrograms.h/ml and 16.42 micrograms.h/ml. The percentage of TCF penetration (AUC(TCF)/AUCserum) was 71% at a dosage of 11 mg/kg and 90% at a dosage of 22 mg/kg.
Afficher plus [+] Moins [-]Efficacy of ivermectin against experimental and natural infections of Gasterophilus spp in ponies
1989
Antiparasitic efficacy of ivermectin against migrating Gasterophilus intestinalis was evaluated in 36 treated and 24 nontreated (n = 12) or vehicle-treated (n = 12) ponies experimentally and naturally infected with G intestinalis and naturally infected with G nasalis. Each pony was experimentally infected with 500 G intestinalis lst instars in 2 divided doses on days -14 and -7 before treatment. On day 0, ivermectin was administered at the rate of 200 microgram/kg of body weight by IV (n = 12) or IM injection (n = 12) or given as an oral paste (n = 12). Ponies were euthanatized and necropsied 21 days after treatment. In each nontreated or vehicle-treated pony, late lst-, lst- to 2nd-instar molt, and early 2nd-instars of G intestinalis were found in the mouth, and 2nd- and 3rd instars of G intestinalis and 3rd instars of G nasalis were found in the stomach. Bots were not found in any ivermectin-treated pony and, thus, ivermectin was 100% effective against oral and gastric stages. Adverse reactions were not observed in ponies given ivermectin by IM injection or orally, but 1 pony given the vehicle IV and 1 pony given ivermectin (in the vehicle) IV had an anaphylactic reaction, resulting in death of the ivermectin-treated pony. It was speculated that the adverse reaction was caused by histamines released in response to vehicle components given by IV injection.
Afficher plus [+] Moins [-]Myoelectric activity of the cecum and right ventral colon in female ponies
1989
Ross, M.W. | Rutkowski, J.A. | Cullen, K.K.
The myoelectric activity of the cecum and right ventral colon (RVC) was studied in 4 female ponies. Eight, bipolar Ag-AgCl electrodes were sequentially placed on the seromuscular layer of the cecum (6 electrodes) and RVC (2 electrodes), and recordings were begun 14 days after surgery. The myoelectric activity for each pony was recorded during 12, 60-minute recording sessions done during the interdigestive period (3 to 7 hours after the morning feeding). Coordinated series of spike bursts were recognized as independent motility patterns in the cecum and in the RVC. Local haustra-haustra myoelectric activity involving approximately 40 cm of the cecal body (0.45 +/- 0.03 spike bursts/min) were detected. A series of spike bursts started at the cecal apex and progressed to, but stopped at, the caudal cecal base (0.04 +/- 0.03 spike bursts/min). Infrequently, a series of spike bursts started at the apex and progressed to the cranial cecal base (0.09 +/- 0.01 spike bursts/min). More commonly, a series of spike bursts with a conduction velocity of 3.8 +/- 0.07 cm/s, began in the cranial base and progressed orally to the cecal apex (0.46 +/- 0.03 spike bursts/min). Spike bursts conducted aborally (propulsion) beginning at the origin of the RVC (0.05 +/- 0.07 spike bursts/min) and spike bursts conducted orally (retropulsion; 0.15 +/- 0.02 spike bursts/min) were seen independent of cecal myoelectric activity. A progessive series of coordinated spike bursts, which began at the cecal apex, were conducted through the cecolic orifice and continued into the RVC (0.42 +/- 0.02 spike bursts/min), representing the only pattern common to the cecum and RVC. This pattern, associated with a loud rush of ingesta heard on auscultation, had a conduction velocity of 5.65 +/- 0.12 cm/s and was always generated in the cecal body, near the apex. An apparent electrical pace-maker area was proposed in this area. Duration of spiking activity during the progressive pattern was significantly (P = 0.0001) greater at electrodes 7 and 8 in the RVC than at any electrode locus in the cecum. Coordinated orally directed spike bursts were detected frequently in the cecum before and after the progressive pattern, indicating a complex sequence of motility patterns may exist.
Afficher plus [+] Moins [-]Immunologic, histopathologic, and bacteriologic responses of five strains of mice to Brucella abortus strain 2308
1989
Pugh, G.W. Jr | Zehr, E.S. | Meador, V.P. | Phillips, M. | McDonald, T.J. | Deyoe, B.L.
A study was conducted to establish baseline data on Brucella abortus infection induced in 5 strains of mice (CBA/NJ, BALB/c, CD-1, C3H/HeN, and C3H/HeJ). The strains were compared on the basis of immunologic, histopathologic, and bacteriologic responses. There were 4 treatment groups for each strain of mice: (1) vaccinated with homologous lipopolysaccharide and challenge exposed to B abortus strain 2308; (2) not vaccinated but challenge exposed; (3) vaccinated but not challenge exposed; and (4) not vaccinated and not challenge exposed. Results indicated that mice can be used for comparative studies on the pathogenesis and immunogenesis of B abortus infections; strains of mice may vary in their responses to Brucella infection, regardless of their vaccination status. Bacteriologic and immunologic responses in mouse strains BALB/c, CD-1, C3H/HeN, and C3H/HeJ, but not those of CBA/NJ, were extrapolative among strains.
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