Effects of 6-hydroxydopamine on the development of the immune system in chickens     

Motobu M  El-Abasy M  Na KJ  Vainio O  Toivanen P  Hirota Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(1):35-42

It has been suggested that the sympathetic nervous system communicates with lymphocytes expressing cell surface receptors for neurotransmitters such as norepinephrine (NE), on the basis of the finding that neurotransmitters modify immune responses in mammalian species. We confirmed that chicken lymphocytes in the brusa of Fabricius, thymus and spleen expressed beta-adrenergic receptor (beta-AR) mRNA from embryonic day (E) 10 and that intracellular cAMP level was elevated by NE, suggesting that lymphocytes express functional beta-AR on their surface at an early embryonal stage. To clarify whether the nervous system is involved in the development of the immune system, the effects of 6-hydroxydopamine (6-OHDA), one of sympathectomizing agents, on chicken lymphocytes was investigated. A single injection of 6-OHDA at a dose of 400 microg into a chicken embryo was carried out at E7 or 14 (as referred to E7 group and E14 group, respectively). NE level and the relative proportion of Bu-1a(+), CD4(+) and CD8(+) cells in the spleen of 3-week-old chickens were not altered by 6-OHDA treatment. However, the proliferative responses and expression of IL-2 mRNA in spleen cells cultured with pokeweed mitogen were reduced in E7 group compared with those of control. Furthermore, in CD8(+) spleen cells of E14 group of 3-week-old chickens, the expression of beta-AR mRNA and the relative increase of intracellular cAMP stimulated with NE were significantly decreased. These results suggest that the sympathetic nervous system affects the development of the immune system.  相似文献   

Comparison of extracapillary and endocapillary blood flow oxygenators for open heart surgery in dogs: efficiency of gas exchange and platelet conservation     

Hoshi K  Tanaka R  Shibazaki A  Nagashima Y  Hirao H  Namiki R  Takashima K  Noishiki Y  Yamane Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(3):357-361

The goal of the current study was to compare the efficiency of gas exchange and platelet conservation of a new extracapillary blood flow oxygenator versus an endocapillary blood flow oxygenator during open heart surgery with extracorporeal circulation in dogs. Dilation and remodeling of the right ventricular outflow tract of dogs was performed using a patch graft technique to simulate pulmonary stenosis. Sequential pre- and post-operative blood analysis revealed that gas exchange efficiency and platelet conservation was significantly greater with the extracapillary blood flow oxygenator than with the endocapillary blood flow oxygenator. However, the priming volume of the extracapillary blood flow oxygenator was significantly greater, leading to hemodilution. We conclude that while the extracapillary blood flow oxygenator provided benefits in terms of gas exchange and platelet conservation, development of a smaller extracapillary blood flow type oxygenator to reduce hemodilution effects would be beneficial.  相似文献   

Protective effects of sugar cane extracts (SCE) on Eimeria tenella infection in chickens     

El-Abasy M  Motobu M  Na KJ  Shimura K  Nakamura K  Koge K  Onodera T  Hirota Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(8):865-871

The effects of oral administration of sugar cane extracts (SCE) on Eimeria tenella oocysts infection in chickens were studied with 2 different experiments. In Experiment 1, 3-week-old inbred chickens (MHC; H.B15) were inoculated into the crop with SCE (500 mg/kg/day) for 1 day or 3 consecutive days, and then challenged with E. tenella sporulated oocysts (2 x 10(4) cells/chicken). In Experiment 2, 1-week-old chickens were orally administered SCE at the same dose for 3 consecutive days, and then initially infected with E. tenella sporulated oocysts (2 x 10(3) cells/chicken). At 2 and 3 weeks of age, these chickens were immunized intravenously with the mixed antigens of sheep red blood cells (SRBC) and Brucella abortus (BA). At 4 weeks of age, chickens were challenged with E. tenella sporulated oocysts (1 x 10(5)/chicken). Challenged chickens with E. tenella oocysts showed markedly decreased body weight gain/day, severe hemorrhage and great number of shedding oocysts in feces and high lesion scores. Oral administration of SCE and initial infection with oocysts (2 x 10 (3)/chicken) resulted in a remarkable improvement in body weight gain/day, hemorrhage, the number of shedding oocysts and lesion score, compare to other infected groups. In addition, SCE-inoculated chickens with the initial infection showed a significant increase in antibody responses against SRBC and BA and also improvement in decreased relative proportions of Bu-1a(+) and CD4( )cells in cecal tonsil lymphocytes of E. tenella-challenged chickens. Cecal tissues of chickens administered SCE and initially infected with E. tenella oocysts showed lower numbers of schizonts, gametocytes and oocysts than those of infected control chickens. These results suggest that SCE have immunostimulating and protective effects against E. tenella infection in chickens.  相似文献   

Effects of a high-protein diet versus dietary supplementation with ammonium chloride on struvite crystal formation in urine of clinically normal cats     

Funaba M  Yamate T  Hashida Y  Maki K  Gotoh K  Kaneko M  Yamamoto H  Iriki T  Hatano Y  Abe M 《American journal of veterinary research》2003,64(8):1059-1064

OBJECTIVE: To evaluate the effects of a high-protein diet versus dietary supplementation with ammonium chloride (NH4Cl) on struvite crystal formation in the urine of clinically normal cats by measuring the urine concentration of hydrochloric acid (HCl)-insoluble sediment, urine pH, struvite activity product (SAP), number of struvite crystals in urine, and urine volume. ANIMALS: 23 healthy adult cats. PROCEDURE: Urine was fractionated by centrifugation with subsequent extraction of the sediment with 1 N HCl (study 1). Diets containing either 29% crude protein or 55% crude protein were fed to cats in a crossover trial of 3 weeks/period (study 2). Diets supplemented with either sodium chloride (NaCl) or NH4Cl were fed, by use of a 3 x 3 Latin-square design with 3 wk/period (study 3). In studies 2 and 3, urine samples were collected for the last 7 days of each period. RESULTS: The HCl-insoluble sediment contained Tamm-Horsfall glycoprotein (THP; study 1). The high-protein diet (study 2) and dietary supplementation with NH4Cl (study 3) resulted in a decrease in urine pH, SAP, and the number of struvite crystals in urine. However, the high-protein diet decreased urine concentrations of HCl-insoluble sediment containing THP (study 2), in contrast to the NH4Cl supplementation that increased urine volume without a significant effect on the urine concentration of the HCl-insoluble sediment (study 3). CONCLUSIONS AND CLINICAL RELEVANCE: Our results indicate that compared with dietary supplementation with NH4Cl, the high-protein diet is preferable as a urine acidifier for the prevention of struvite crystal formation in clinically normal cats.  相似文献   

Detection of mitogen-induced lymphocyte proliferation by bromodeoxyuridine (BrdU) incorporation in the chicken   总被引：2，自引：0，他引：2  

Motobu M  El-Abasy M  Na KJ  Hirota Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(4):377-379

3H-thymidine (3H-TdR) incorporation assay has been generally used to measure lymphocyte proliferation in the chicken. Disadvantages of this assay are that radioisotope is biological hazard to the person and environment and that it can not measure which subset of lymphocytes proliferates. In this study, bromodeoxyuridine (BrdU) incorporation assay by flow cytometry was compared with 3H-TdR incorporation assay. As a result, BrdU incorporation assay showed a strong correlation with 3H-TdR incorporation assay, and it could be applied simultaneously to detect BrdU incorporation and expression of cell surface marker antigens. These results suggest that the BrdU incorporation assay by flow cytometry is useful to analyze lymphocyte proliferation in detail.  相似文献   

Immunostimulating and growth-promoting effects of sugar cane extract (SCE) in chickens     

El-Abasy M  Motobu M  Shimura K  Na KJ  Kang CB  Koge K  Onodera T  Hirota Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(11):1061-1063

Polymorphonuclear cells of the peripheral blood in the chicken significantly increased their phagocytosis when cultured with sugar cane extract (SCE; 250-1,000 microg/ml) for 24 hr. Chickens orally administered SCE (500 mg/kg/day) for 3 or 6 consecutive days at 1 week of age showed significantly higher body weight and gain in body weight/day and a lower food conversion ratio within the growing period of 6 weeks than physiological saline-administered control chickens. Furthermore, oral administration of SCE also resulted in significantly higher immune responses against sheep red blood cells and Brucella abortus. These results suggest that SCE has immunostimulating and growth promoting effects in chickens.  相似文献   

Changes in platelet life span in dogs with mitral valve regurgitation     

Tanaka R  Murota A  Nagashima Y  Yamane Y 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(4):446-451

Platelet life span was measured in dogs with experimentally-induced mitral regurgitation (MR) by using an in vitro whole-blood biotinylation technique to evaluate the effects of shear stress induced by MR. Mitral regurgitation was created in healthy dogs by ablation of the mitral valve chordae tendineae. Mitral regurgitation was identified by auscultation and postoperative color Doppler echocardiography. Platelets were biotinylated. and derivatized blood was reinfused into the dogs. Biotinylated platelet disappearance was measured over time to determine platelet life span. Pre- and postablation platelet life span was compared in each dog. Platelet life span was shorter in dogs with experimentally induced MR. Shear stress from MR was postulated to shorten platelet life span. Alternations in platelet function and life span may contribute to the progression of cardiovascular disease in dogs with MR. Further studies are required to determine if platelet dysfunction is related to disease progression in these patients.  相似文献   

Retrospective study of clinical complications occurring after arterial punctures in 111 dogs     

Shiroshita Y  Tanaka R  Shibazaki A  Yamane Y 《The Veterinary record》2000,146(1):16-19

The clinical complications occurring after 111 dogs had undergone arterial punctures were reviewed in relation to the dogs' breed, bodyweight, age, sex and underlying diseases. Seven of the dogs had moderate to extensive ecchymoses, which were significantly more common in dogs under 3.5 kg in bodyweight and in dogs with disorders of the cardiovascular system.  相似文献   

Ornithobacterium rhinotracheale infection in Japan: preliminary investigations     

Sakai E  Tokuyama Y  Nonaka F  Ohishi S  Ishikawa Y  Tanaka M  Taneno A 《The Veterinary record》2000,146(17):502-503

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The role of CD4(+) or CD8(+) T cells in the protective immune response of BALB/c mice to Neospora caninum infection     

Tanaka T  Hamada T  Inoue N  Nagasawa H  Fujisaki K  Suzuki N  Mikami T 《Veterinary parasitology》2000,90(3):183-191

The role of CD4(+) or CD8(+) T cells in the immune response of BALB/c mice against Neospora caninum infection was examined by using anti-CD4 and/or anti-CD8 monoclonal antibodies (mAbs). Mice were intraperitoneally inoculated with anti-CD4 and/or anti-CD8 mAbs before and after infection with N. caninum and observed for 30 days after infection. Most of the anti-CD4 mAb-treated mice and all of the anti-CD4 and anti-CD8 mAbs-treated mice died within 30 days post-infection (p.i.). In contrast, 100% of PBS-treated mice and 70% of anti-CD8 mAb-treated mice survived more than 30 days. When compared with phosphate-buffered saline (PBS)-treated mice, the weight of mice treated with mAbs tended to decrease. From these results CD4(+) T cells, but not CD8(+) T cells, have an important role for protection of mice against N. caninum infection. Serum antibody levels to N. caninum in infected-mice treated with anti-CD4 mAb or a mixture of anti-CD4 and anti-CD8 mAbs were lower than those in the infected mice treated with anti-CD8 mAb or PBS. The mice treated with anti-interferon-gamma (IFN-gamma) mAb produced high antibody levels to N. caninum, but all mice died within 18 days p.i. These results indicated that IFN-gamma is an important cytokine for protection against N. caninum infection at the early stage of infection. However, since CD4(+) T cells against N. caninum were essential to the production of specific antibody, these antibodies might have important roles in host protection at the later stage of infection.  相似文献