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Use of polymerase chain reaction to detect porcine parvovirus associated with swine embryos
1994
Gradil, C.M. | Harding, M.J. | Lewis, K.
The role of porcine parvovirus (PPV) in inducing reproductive failure in swine has been extensively documented. However, information is not available as to the risk of ppv transmission by embryo transfer. Using the polymerase chain reaction (PCR) technique, PPV-specific DNA was detected in association with 4-day-old porcine embryos incubated in vitro in the presence of NADL-8 strain of PPV, despite attempts to rid the embryos of virus by either washing or treatment with pronase or trypsin. The presence of PPV in embryos collected from acutely infected swine was not detected by PCR, although PPV DNA was detected in the proximal portion of the reproductive tract during the early stages of infection. Viral-specific nucleic acid was not detected in embryos transferred from infected donors to seronegative recipients and retrieved and assayed on the 15th and 32nd days of gestation. Results of the use of PCR to detect PPV associated with swine female reproductive tract and embryos ascribe minimal risk to the transmission of PPV to seronegative recipients through embryo transfer.
Afficher plus [+] Moins [-]Comparative use of various mydriatic drugs in kestrels (Falco tinnunculus)
1994
Mikaelian, I. | Paillet, I. | Williams, D.
The mydriatic effect of 3 curare-like neuromuscular blocking agents was tested in European kestrels (Falco tinnunculus) after topical application. Alcuronium chloride (5 mg/ml) was found to be effective at a dose of 1 drop (20 drops = 1 ml) administered twice at a 15-minute interval. Mydriasis was achieved at t = 26 +/- 11 minutes, maximal effect was reached at t = 60 +/- 39 minutes, and sufficient mydriasis ended at t = 364 +/- 134 minutes. Nevertheless, side effects, including temporary full paralysis in 1 bird, indicated that this drug should not be used. Pancuronium bromide (2 mg/ml) had an inconsistent effect on each bird at a dose of 2 drops administered twice at 15-minute intervals, and total mydriasis was not reached in 5 of 8 birds. Mydriasis was achieved at t = 34 +/- 11 minutes, maximal effect was reduced and reached at t = 43 +/- 13 minutes, and sufficient mydriasis ended at t = 90 +/- 39 minutes. Vecuronium bromide (4 mg/ml) was administered at a dose of 2 drops, 3 times, at 15-minute intervals. Mydriasis was achieved at t = 23 +/- 8 minutes, maximal effect was reached at t = 65 +/- 12 minutes, and sufficient mydriasis ended at t = 253 +/- 65 minutes. Side effects were not detected. Vecuronium bromide should be used in raptorial birds whenever retinal examination requires fundoscopy.
Afficher plus [+] Moins [-]Hepatic total 3 alpha-hydroxy bile acids concentration and enzyme activities in prednisone-treated dogs
1994
Solter, P.F. | Hoffmann, W.E. | Chambers, M.D. | Schaeffer, D.J. | Kuhlenschmidt, M.S.
High serum alkaline phosphatase (ALP) activity is considered a sensitive marker of cholestasis in most mammalian species, including dogs. Induction of high serum ALP activity in association with cholestasis is dependent on high hepatic bile acids concentrations. Treatment of dogs with glucocorticoids also results in high serum ALP activity. The possible causal relation between serum ALP activity and bile acids concentration was investigated in dogs treated with glucocorticoids. The relation of glucocorticoid treatment to changes in the activity of individual ALP isoenzymes, alanine transaminase (ALT) and gamma-glutamyltransferase (GGT) also was investigated. Eight conditioned dogs were given 4 mg of prednisone/kg of body weight, IM, daily for 10 days. Blood samples were taken prior to treatment and on treatment days 3, 5, 7, and 10. Liver tissue was then taken from each dog. Serum total ALP activity was significantly (P < 0.05) high at day 3 in prednisone-treated dogs. Isoenzyme analysis indicated that this increase was attributable to an increase in the liver ALP isoenzyme (LALP). Significant increases in serum corticosteroid-induced ALP (CALP) and bone ALP were first observed on days 7 and 10, respectively. Serum ALT and GGT activities were significantly increased by day 5. Increased serum or hepatic tissue bile acids concentrations were not observed in prednisone-treated dogs, compared with values in 8 clinically normal (control) dogs, but were high in 3 dogs with complete bile duct ligation. Hepatic activities of LALP, CALP, and GGT were higher in prednisone-treated dogs than values in controls, indicating probable increased hepatic synthesis of these enzymes. Hepatic ALT activity was not increased. The ratio of serum to tissue LALP activity was increased in prednisone-treated dogs, compared with values in controls, indicating that LALP may have been preferentially released into serum. There was no difference in the ratio of serum to liver GGT activity between prednisone-treated dogs and controls. The LALP and GGT ratios were increased in bile duct-obstruction dogs. It was concluded that, although LALP is the principal ALP isoenzyme in serum during the first 10 days of prednisone treatment, hepatic bile acid concentrations are not increased and, therefore, are not likely to be responsible for induction and release of ALP into serum. Prednisone may, therefore, be directly responsible for induction of ALP activity in dogs treated thusly.
Afficher plus [+] Moins [-]Dexamethasone-induced haptoglobin release by calf liver parenchymal cells
1994
Higuchi, H. | Katoh, N. | Miyamoto, T. | Uchida, E. | Yuasa, A. | Takahashi, K.
Parenchymal cells were isolated from the liver of male calves, and monolayer cultures formed were treated with glucocorticoids to examine whether haptoglobin, appearance of which is associated with hepatic lipidosis (fatty liver) in cattle, is induced by steroid hormones. Without addition of dexamethasone, only trace amounts of haptoglobin were detected in culture medium. With addition of dexamethasone (10(-12) to 10(-4)M), considerable amounts of haptoglobin were released into the medium. Maximal release was observed at concentrations of 10(-8) to 10(-6)M dexamethasone. Haptoglobin release was similarly induced by cortisol, although the effect was less potent than that of dexamethasone. Actinomycin D (a known protein synthesis inhibitor) dose-dependently reduced amounts of haptoglobin released in response to 10(-8)M dexamethasone. Dexamethazone also induced annexin I, which is known to be synthesized in response to glucocorticoids. Dexamethasone treatment resulted in reduced protein kinase C activity in the cell cytosol, which has been shown to be an early event in dexamethasone-treated cells. Other than glucocorticoids, estradiol induced haptoglobin release, whereas progesterone was less effective. The association of haptoglobin with hepatic lipidosis can be reasonably explained by the fact that haptoglobin production by the liver is induced by glucocorticoids and estradiol, and these steroid hormones are triggers for development of hepatic lipidosis in cattle.
Afficher plus [+] Moins [-]Hyperplasia of brown adipose tissue after chronic stimulation of beta3-adrenergic receptor in rats
1994
Nagase, I. (Hokkaido Univ., Sapporo (Japan). Faculty of Veterinary Medicine) | Sasaki, N. | Tsukazaki, K. | Yoshida, T. | Morimatsu, M. | Saito, M.
Estimate of genetic variations in Hokkaido brown bears (Ursus arctos yesoensis) by DNA fingerprinting
1994
Tsuruga, H. (Hokkaido Univ., Sapporo (Japan). Faculty of Veterinary Medicine) | Mano, T. | Yamanaka, M. | Kanagawa, H.
The inhibitory action of lead on mechanical responses of the proventricular smooth muscle in the chick
1994
Kubota, K. (Hokkaido Univ., Sapporo (Japan). Faculty of Veterinary Medicine) | Ito, S. | Ohta, T. | Nakazato, Y. | Ohga, A.
Theileriosis in Zambia: Etiology, epidemiology and control measures
1994
Nambota, A. (University of Zambia, Lusaka) | Samui, K. | Sugimoto, C. | Kakuta, T. | Onuma, M.
Development of single blastomeres from 4-cell stage embryos after aggregation with parthenogenones in mice
1994
Pinyopummin, A. (Hokkaido Univ., Sapporo (Japan). Faculty of Veterinary Medicine) | Takahashi, Y. | Hishinuma, M. | Kanagawa, H.
The inhibitory effects of MgSO4 on the multiplication and transcription of mouse hepatitis virus
1994
Mizutani, T. (Hokkaido Univ., Sapporo (Japan). Faculty of Veterinary Medicine) | Hayashi, M. | Maeda, A. | Ishida, K. | Watanabe, T. | Namioka, S.