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Toxoplasmose experimental em éguas gestantes: estudo dos fetos e placentas | Experimental toxoplasmosis in pregnant mares: a study of fetuses and placentas Полный текст
1995
Marques, Luiz Carlos | Costa, Alvimar José da | Lopes, Carlos Wilson Gomes | Moraes, Flávio Ruas de | Moraes, Julieta Rodine Engracia de
Toxoplasmose experimental em éguas gestantes: estudo dos fetos e placentas | Experimental toxoplasmosis in pregnant mares: a study of fetuses and placentas Полный текст
1995
Marques, Luiz Carlos | Costa, Alvimar José da | Lopes, Carlos Wilson Gomes | Moraes, Flávio Ruas de | Moraes, Julieta Rodine Engracia de
Nove éguas prenhes foram inoculadas, via oral, com oocistos esporulados de T. gondii. Três éguas prenhes, não infectadas, foram mantidas como testemunhas. O T. gondii foi encontrado na placenta, retina, esôfago, fígado, diafragma, cérebro, medula espinhal, músculo esquelético, coração, pulmão e língua de potros nascidos de éguas inoculadas. A obtenção e T. gondii em diferentes tecidos, desses potros reforça a hipótese da transmissão transplacentária deste protozoário cm eqüinos. | Nine pregnant mares were orally infected with sporulated T. gondii oocysts. Three additional, pregnant, uninfected mares were used as control. T. gondii were found in the placenta, retina, esophagus, liver, diaphragm, brain, spinal cord, skeletal muscles, heart, lung and tongue of newborn foals from experimentally infected mares. The finding of T. gondii in the foals reinforced the hupothesis of transplacentary transmission of this protozoa in equines.
Показать больше [+] Меньше [-]Toxoplasmose experimental em éguas gestantes: estudo dos fetos e placentas Полный текст
1995
Luiz Carlos Marques | Alvimar José da Costa | Carlos Wilson Gomes Lopes | Flávio Ruas de Moraes | Julieta Rodine Engracia de Moraes
Nove éguas prenhes foram inoculadas, via oral, com oocistos esporulados de T. gondii. Três éguas prenhes, não infectadas, foram mantidas como testemunhas. O T. gondii foi encontrado na placenta, retina, esôfago, fígado, diafragma, cérebro, medula espinhal, músculo esquelético, coração, pulmão e língua de potros nascidos de éguas inoculadas. A obtenção e T. gondii em diferentes tecidos, desses potros reforça a hipótese da transmissão transplacentária deste protozoário cm eqüinos.
Показать больше [+] Меньше [-]Reparação cirúrgica da córnea de cão usando pericárdio como prótese | The surgical repair of the cornea of the dog using pericardium as a keratoprosthesis Полный текст
1995
Barros, Paulo Sérgio de Moraes | Safatle, Angélica de Mendonça Vaz | Malerba, Telma Aparecida | Burnier Junior, Miguel
Reparação cirúrgica da córnea de cão usando pericárdio como prótese | The surgical repair of the cornea of the dog using pericardium as a keratoprosthesis Полный текст
1995
Barros, Paulo Sérgio de Moraes | Safatle, Angélica de Mendonça Vaz | Malerba, Telma Aparecida | Burnier Junior, Miguel
A substituição da córnea em lesões oculares tem merecido a atenção dos oftalmologistas, sendo que vários materiais têm sido usados para este fim. O pericárdio de eqüino, conservado em glicerina, foi usado no reparo de lesões penetrantes de córnea de dois cães, um pela excisão de melanoma límbico, outro pela presença de estafiloma periférico. Cão, Pastor Alemão, com 6 anos de idade, apresentando massa de 1 cm de diâmetro, localizada na região temporal do limbo esclero-corneano do olho direito, com 2 meses de evolução e cão de 4 meses, mestiço, que teve ferida sua córnea esquerda com prolapso de íris, em conseqüência de arranhadura de gato, 5 dias antes, foram examinados no Serviço de Oftalmologia do Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo. As lesões de ambos os animais foram reparadas com fragmento de pericárdio de eqüino para fechamento do defeito produzido. Aplicação de pomada antibiótica e colírio de atropina de 1% foi instituída no pós-operatório. A pressão intra-ocular foi baixa nos primeiros dias subseqüentes à cirurgia, mas foi gradativamente aumentando chegando a valores normais. Inicialmente, tecido de granulação foi observado próximo ao implante, e opacificação do pericárdio permaneceu. Colírio de dexametasona foi então indicado, sendo que o tecido de granulação desapareceu dois meses após a cirurgia. A câmara anterior permaneceu profunda durante toda a evolução. O acompanhamento pós-operatório mostrou os olhos em boas condições após dezoito meses. | Significant advances in corneal repair have been made in the past. Tissue graft has been used to repair full-thickness defects of the cornea and sclera. Equine pericardium preserved in glycerol was used to repair full-thickness corneal lesions after limbal melanoma excision and corneal wound with iris prolapse. A six-year old male, German Shepherd, with 1 cm of diameter, dark-pigmented mass at the temporal limbus of the right eye, with two months of evolution, and a four month old female mixed breed dog, with a corneal wound and iris prolapse, in the left eye, secondary to a cat scratch 5 days earlier. In both cases a piece of pericardium was sutured close to the corneal defects. An antibiotic ointment and atropine 1% eye drops were used. The intraocular pressure was low in the following days, but arose to normal values. All other structures were normal. A granulation tissue initially grew near the patch, and the opacity of the pericardium remained. Dexamethasone eye drops and ointment were used, and the granulation tissue disappeared two months after surgery. Eighteen months follow-up showed the eyes in good condition, although opaqueness was still present.
Показать больше [+] Меньше [-]Reparação cirúrgica da córnea de cão usando pericárdio como prótese Полный текст
1995
Paulo Sérgio de Moraes Barros | Angélica de Mendonça Vaz Safatle | Telma Aparecida Malerba | Miguel Burnier Junior
A substituição da córnea em lesões oculares tem merecido a atenção dos oftalmologistas, sendo que vários materiais têm sido usados para este fim. O pericárdio de eqüino, conservado em glicerina, foi usado no reparo de lesões penetrantes de córnea de dois cães, um pela excisão de melanoma límbico, outro pela presença de estafiloma periférico. Cão, Pastor Alemão, com 6 anos de idade, apresentando massa de 1 cm de diâmetro, localizada na região temporal do limbo esclero-corneano do olho direito, com 2 meses de evolução e cão de 4 meses, mestiço, que teve ferida sua córnea esquerda com prolapso de íris, em conseqüência de arranhadura de gato, 5 dias antes, foram examinados no Serviço de Oftalmologia do Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo. As lesões de ambos os animais foram reparadas com fragmento de pericárdio de eqüino para fechamento do defeito produzido. Aplicação de pomada antibiótica e colírio de atropina de 1% foi instituída no pós-operatório. A pressão intra-ocular foi baixa nos primeiros dias subseqüentes à cirurgia, mas foi gradativamente aumentando chegando a valores normais. Inicialmente, tecido de granulação foi observado próximo ao implante, e opacificação do pericárdio permaneceu. Colírio de dexametasona foi então indicado, sendo que o tecido de granulação desapareceu dois meses após a cirurgia. A câmara anterior permaneceu profunda durante toda a evolução. O acompanhamento pós-operatório mostrou os olhos em boas condições após dezoito meses.
Показать больше [+] Меньше [-]Alterações do líquido peritoneal em eqüinos com desconforto abdominal e suas relações com o tipo de lesão implantada e evolução após tratamento médico ou cirúrgico: análise de 74 casos | Changes in the peritoneal fluid of horses with abdominal discomfort and its relations to the kind and evolution of the lesion after medical or surgical treatment: study of 74 cases Полный текст
1995
Baccarin, Raquel Yvonne Arantes | Thomassian, Armen | Nicoletti, José Luiz Mello | Gandolfi, Waldir | Hussni, Carlos Alberto | Lopes, Raimundo Souza
Alterações do líquido peritoneal em eqüinos com desconforto abdominal e suas relações com o tipo de lesão implantada e evolução após tratamento médico ou cirúrgico: análise de 74 casos | Changes in the peritoneal fluid of horses with abdominal discomfort and its relations to the kind and evolution of the lesion after medical or surgical treatment: study of 74 cases Полный текст
1995
Baccarin, Raquel Yvonne Arantes | Thomassian, Armen | Nicoletti, José Luiz Mello | Gandolfi, Waldir | Hussni, Carlos Alberto | Lopes, Raimundo Souza
Este trabalho tem como objetivo interrelacionar o exame do líquido peritoneal de eqüinos com desconforto abdominal e a indicação terapêutica para estes animais, levando-se em consideração a localização do processo patológico, a presença ou não de estrangulamento vascular, o tratamento instituído e a característica do líquido peritoneal como transudato modificado ou exsudato. Para isso os autores trabalharam com 373 prontuários de eqüinos com desconforto abdominal, que foram atendidos no Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia - UNESP- Botucatu, no período de 1985 a 1991. Destes prontuários, 98 foram selecionados, onde a abdominocentese e o exame do líquido peritoneal haviam sido realizados rotineiramente. Observou-se maior ocorrência de líquido peritoneal tipo exsudato do que transudato modificado. Independentemente da sede da lesão, as afecções que apresentaram estrangulamento vascular possuíram índices de sobrevivência menor, sendo que a maior ocorrência de estrangulamento vascular possuíram índices de sobrevivência menor que a maior ocorrência de estrangulamento vascular deu-se no intestino delgado. Houve melho índice de recuperação em animais com processos patológicos de intestino grosso. Entre os parâmetros estudados nos exames dos líquidos peritoneais, observou-se que a coloração sanguinolenta das amostras foi a que mais evidenciou a presença de estrangulamento vascular e isquemia intestinal. Por fim a citologia e a análise de líquido peritoneal não foram suficientes para diferenciar as várias causas de desconforto abdominal, devido às grandes variações de cada processo patológico entre si. Porem, salienta-se que quando associadas com a avaliação clínica do animal, podem nos evidenciar a necessidade de intervenção cirúrgica. | The purpose of this paper is to view the interrelation between the peritoneal fluid analysis from horses with abdominal discomfort, regarding the pathology site, the occurrence or not of strangulating obstruction, the treatment performed and the presence of peritoneal fluid, classified either as modified transudate or exsudate. In order to achieve that, 373 clinical records of colicky horses referred to the Veterinary Hospital between 1985 and 1991 were studied, and 98 of these, were selected, in which peritoneal fluid sampling and analysis had been carried out in a routine manner. Greater amount of exsudate than that of modified transudate was observed. Horses with wide spread intestinal disease showed the best recovery rates. Regardless of the site of the lesion, those exhibiting strangulating obstruction had the lowest rates of survival, and this kind of obstruction was more frequently observed in the small intestine. Among the parameters considered in the peritoneal fluid analysis, fluid color was the most reliable indicator od strangulating obstruction and/or intestinal ischemia. Finally, peritoneal fluid analysis and citology alone were not sufficient to diagnose the cause of the colic, due to the great variation observed in each pathology group: associated to the clinical evaluation of the patient, however, they can bring up the need for surgical intervention.
Показать больше [+] Меньше [-]Alterações do líquido peritoneal em eqüinos com desconforto abdominal e suas relações com o tipo de lesão implantada e evolução após tratamento médico ou cirúrgico: análise de 74 casos Полный текст
1995
Raquel Yvonne Arantes Baccarin | Armen Thomassian | José Luiz Mello Nicoletti | Waldir Gandolfi | Carlos Alberto Hussni | Raimundo Souza Lopes
Este trabalho tem como objetivo interrelacionar o exame do líquido peritoneal de eqüinos com desconforto abdominal e a indicação terapêutica para estes animais, levando-se em consideração a localização do processo patológico, a presença ou não de estrangulamento vascular, o tratamento instituído e a característica do líquido peritoneal como transudato modificado ou exsudato. Para isso os autores trabalharam com 373 prontuários de eqüinos com desconforto abdominal, que foram atendidos no Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia - UNESP- Botucatu, no período de 1985 a 1991. Destes prontuários, 98 foram selecionados, onde a abdominocentese e o exame do líquido peritoneal haviam sido realizados rotineiramente. Observou-se maior ocorrência de líquido peritoneal tipo exsudato do que transudato modificado. Independentemente da sede da lesão, as afecções que apresentaram estrangulamento vascular possuíram índices de sobrevivência menor, sendo que a maior ocorrência de estrangulamento vascular possuíram índices de sobrevivência menor que a maior ocorrência de estrangulamento vascular deu-se no intestino delgado. Houve melho índice de recuperação em animais com processos patológicos de intestino grosso. Entre os parâmetros estudados nos exames dos líquidos peritoneais, observou-se que a coloração sanguinolenta das amostras foi a que mais evidenciou a presença de estrangulamento vascular e isquemia intestinal. Por fim a citologia e a análise de líquido peritoneal não foram suficientes para diferenciar as várias causas de desconforto abdominal, devido às grandes variações de cada processo patológico entre si. Porem, salienta-se que quando associadas com a avaliação clínica do animal, podem nos evidenciar a necessidade de intervenção cirúrgica.
Показать больше [+] Меньше [-]Evaluation of pulmonary function and analgesia in dogs after intercostal thoracotomy and use of morphine administered intramuscularly or intrapleurally and bupivacaine administered intrapleurally
1995
Stobie, D. | Caywood, D.D. | Rozanski, E.A. | Bing, D.R. | Dhokarikar, P. | Raffe, M.R. | Kannan, M.S. | King, V.L. | Hegstad, R.L. | Randall, D.A.
Eighteen dogs undergoing lateral thoracotomy at the left fifth intercostal space were randomly assigned to 1 of 3 postoperative analgesic treatment groups of 6 dogs each as follows: group A, morphine, 1.0 mg/kg of body weight, IM; group B, 0.5% bupivacaine, 1.5 mg/kg given interpleurally; and group C, morphine, 1.0 mg/kg given interpleurally. Heart rate, respiratory rate, arterial blood pressure, arterial blood gas tensions, alveolar-arterial oxygen differences, rectal temperature, pain score, and pulmonary mechanics were recorded hourly for the first 8 hours after surgery, and at postoperative hours 12, 24, and 48. These values were compared with preoperative (control) values for each dog. Serum morphine and cortisol concentrations were measured at 10, 20, and 30 minutes, hours 1 to 8, and 12 hours after treatment administration . All dogs had significant decreases in pHa, PaO2, and oxygen saturation of hemoglobin, and significant increases in PaCO2 and alveolar-arterial oxygen differences in the postoperative period, but these changes were less severe in group-B dogs. Decreases of 50% in lung compliance, and increases of 100 to 200% in work of breathing and of 185 to 383% in pulmonary resistance were observed in all dogs after surgery. Increases in work of breathing were lower, and returned to preoperative values earlier in group-B dogs. The inspiratory time-to-total respiratory time ratio was significantly higher in group-B dogs during postoperative hours 5 to 8, suggesting improved analgesia. Blood pressure was significantly lower in group-A dogs for the first postoperative hour. Significant decreases in rectal temperature were observed in all dogs after surgery, and hypothermia was prolonged in dogs of groups A and C. Significant differences in pain score were not observed between treatment groups. Cortisol concentration was high in all dogs after anesthesia and surgery, and was significantly increased in group-B dogs at hours 4 and 8. Significant differences in serum morphine concentration between groups A and C were only observed 10 minutes after treatment administration. In general, significant differences in physiologic variables between groups A and C were not observed. Results of the study indicate that anesthesia and thoracotomy are associated with significant alterations in pulmonary function and lung mechanics. Interpleurally administered bupivacaine appears to be associated with fewer blood gas alterations and earlier return to normal of certain pulmonary function values. Interpleural administration of morphine does not appear to provide any advantages, in terms of analgesia or pulmonary function, compared with its IM administration.
Показать больше [+] Меньше [-]Investigation of pseudorabies virus DNA and RNA in trigeminal ganglia and tonsil tissues of latently infected swine
1995
Cheung, A.K.
Pseudorabies virus (PRV) nucleic acids in the trigeminal ganglia and tonsils of swine latently infected with the virus were analyzed. By use of DNA-polymerase chain reaction (PCR), 14 of 14 trigeminal ganglia and 12 of 14 tonsils were positive for PRV genomes. By use of RNA-PCR, RNA containing the large latency transcript splice junction were detected in 4 of 4 trigeminal ganglia and 4 of 5 tonsils. In general, results of both PCR procedures indicated that the amounts of PRV DNA and RNA per microgram of cellular nucleic acids were higher in trigeminal ganglia than in tonsils. Identification of peripheral tissues that harbor latent PRV is an important asset for PRV research. The presence of large latency transcript in tonsil tissues, in the absence of virus replication, is a critical characteristic, which indicates that the tonsil is a site of PRV latency. For diagnostic purposes, animals need not be euthanatized to obtain their nervous tissue to determine latency; instead, tonsil biopsy specimens could be obtained from live animals for analysis. For pathogenesis studies, multiple specimens obtained sequentially from the same animal would be available for examination for the duration of the experiment.
Показать больше [+] Меньше [-]Comparison of argyrophilic nucleolar organizer regions by counting and image analysis in canine mammary tumors
1995
Destexhe, E. | Vanmanshoven, P. | Coignoul, F.
Two techniques for evaluating argyrophilic nucleolar organizer regions (AgNOR) were compared on 74 canine mammary tumors to discriminate between benign and malignant lesions. For each lesion, direct counting of AgNOR on at least 100 cell nuclei was compared with area, perimeter, and integrated optical density AgNOR dot values determined by image analysis. Significant differences between benign and malignant tumors were observed with both methods; however, lesions determined as aggressive or proliferative by histologic evaluation were only singled out by image analysis measurements. Image analysis, in our hands, was a reliable, precise, and convenient technique to characterize malignancy in canine mammary tumors.
Показать больше [+] Меньше [-]Effect of hypertonic saline solution on left ventricular afterload in normovolumic dogs
1995
Constable, P.D. | Muir, W.W. III. | Binkley, P.F.
The effects of hypertonic saline solution (HSS) and hyperosmotic dextrose (HD; 2,400 mosm/L, 4 ml/kg of body weight) on left ventricular afterload were determined in normovolumic, chloralose-anesthetized, autonomically blocked dogs (n = 8). Solutions were infused IV over 3 minutes. Left ventricular afterload was assessed by use of a dual-tipped micromanometer catheter with an electromagnetic fluid-velocity sensor located in the ascending aorta, and the impedance spectrum was calculated after Fourier analysis of signal-averaged aortic pressure and flow signals. Hypertonic saline solution and HD decreased peripheral resistance, reflection coefficient at zero frequency, and frequency of the first zero crossing of the phase angle for 3 to 5 minutes after either fluid was administered. Characteristic impedance was not altered by HSS or HD. These impedance spectrum changes indicate transient vasodilatation and afterload reduction. We conclude that the vascular effect of an ionic hyperosmotic solution (HSS) is similar to that of a nonionic hyperosmotic solution (HD), and that HSS and HD transiently decrease afterload in normovolumic dogs. The duration of the afterload reduction after HSS administration appeared to be too short to be of great clinical benefit.
Показать больше [+] Меньше [-]Effects of hydrogen peroxide on isolated trachealis muscle of horses
1995
Olszewski, M.A. | Robinson, N.E. | Yu, M.F. | Derksen, F.J.
During acute bouts of recurrent airway obstruction (heaves) in horses, neutrophils that are capable of increased production of reactive oxygen species accumulate in the airways. In the study reported here, the effect of hydrogen peroxide (H2O2; 1 micromolar to 0.1M), one of these reactive oxygen species products, on the responses of isolated trachealis muscle of horses was determined. Before and after incubation with H2O2, contractile responses to acetylcholine, electrical field stimulation (EFS), 127 mM KCl, and relaxation responses to isoproterenol and activation of the nonadrenergic noncholinergic inhibitory response (iNANC) were evaluated. Beginning at 1 mM, H2O2 contracted trachealis muscle in a concentration-dependent manner. This contraction was unaffected by atropine (1 micromolar), tetrodotoxin (1 micromolar), or 1 micromolar meclofenamate. Contraction of trachealis muscle in response to H2O2 is, therefore, not attributable to release of prostaglandins, acetylcholine, or other neurotransmitters. Above a concentration of 0.1 mM, H2O2 depressed the responses to EFS. acetylcholine, and KCl in a concentration-dependent manner. At 0.1M, H2O2 decreased the maximal responses to EFS, acetylcholine, and KCl by 62.7 +/- 7.2, 60.58 +/- 6.12, and 37.8 +/- 9.54%, respectively. In the presence of meclofenamate (1 micromolar), partial but significant protection against 1 to 100 mM H2O2 was observed. In tracheal strips contracted with 0.3 micromolar methacholine, H2O2 had no effect on the isoproterenol concentration-response curve. Up to a concentration of 100 mM, H2O2 had no effect on iNANC response. However, in the presence of 100 mM H2O2, this response was abolished in 2 of 4 horses. We conclude that high concentrations of H2O2 affected the responses of airway smooth muscle by actions on neurotransmission, muscarinic receptors, and downstream from receptors; some of the H2O2 effects were in part mediated by cyclooxygenase products; and H2O2 had no effect on beta-adrenergic- or iNANC-induced relaxation.
Показать больше [+] Меньше [-]Pharmacokinetics of bacampicillin in equids
1995
Sarasola, P. | McKellar, Q.A.
Bacampicillin hydrochloride is an ester prodrug that is hydrolyzed to ampicillin after its absorption from the gastrointestinal tract. It was administered intragastrically at a dose rate of 13.5 mg/kg of body weight to ponies and horses, and was highly bioavailable (F = 41.0%), compared with other penicillins in adult horses. The high peak ampicillin plasma concentration of 6.1 +/- 0.5 micrograms/ml achieved and persistence of the antibiotic at concentration of 0.3 +/- 0.1 micrograms/ml 6 hours after its intragastric administration, suggest that bacampicillin hydrochloride may reach suitable bactericidal concentrations for treatment of infections caused by susceptible microorganisms. In a separate experiment, dichlorvos, an organophosphate compound that inhibits some of the esterase activity in plasma, was administered orally to the same animals at a dose rate of 40 mg/kg followed by intragastric administration of bacampicillin hydrochloride at a dose of 13.5 mg/kg. Plasma pseudocholinesterase and erythrocyte acetylcholinesterase activities were reduced to < 5% of reference (predichlorvos) values after dichlorvos administration. However, rate of hydrolysis of bacampicillin into ampicillin was not affected. Consequently, the disposition and fate of bacampicillin when administered intragastrically 1 day after dichlorvos administration were similar to the values obtained after administration of bacampicillin alone. Intragastric coadministration of probenecid at a dose rate of 75 mg/kg and bacampicillin at 13.5 mg/kg limited absorption of the antibiotic from the gastrointestinal tract. This suggests existence of a common transport mechanism for bacampicillin and probenecid in the gastrointestinal wall, and precludes use of this combination for treatment. The bioavailable fraction of ampicillin after combination treatment indicated prolonged residence time in the plasma, presumably as a consequence of reduced renal tubular secretion.
Показать больше [+] Меньше [-]Complement component C3b and immunoglobulin Fc receptors on neutrophils from calves with leukocyte adhesion deficiency
1995
Worku, M. | Paape, M.J. | Di Carlo, A. | Kehrli, M.E. Jr | Marquardt, W.W.
Complement component C3b and immunoglobulin Fc receptors on neutrophils from calves with leukocyte adhesion deficiency
1995
Worku, M. | Paape, M.J. | Di Carlo, A. | Kehrli, M.E. Jr | Marquardt, W.W.
Receptors for opsonins, such as complement component C3b (CR1) and immunoglobulins, Fc receptors, interact with adhesion glycoproteins in mediating immune functions. Defects in expression of the adhesion glycoproteins CD11/CD18 results in severely hampered in vitro and in vivo adherence-related functions of leukocytes. Little is known regarding the effect of leukocyte adhesion deficiency (LAD) on ligand binding and receptor expression. We investigated the binding and expression of CR1 and Fc receptors by bovine neutrophils isolated from dairy calves suffering from LAD, compared with clinically normal (hereafter referred to as normal) age-matched calves. Neutrophils were also assayed for endogenously bound IgG and IgM and for exogenous binding of C3b, IgG1, IgG2, IgM, and aggregated IgG (aIgG), using flow cytometry. Luminol-enhanced chemiluminescence (CL) production in response to IgG2 opsonized zymosan was studied, and specific inhibition of CL was used to determine the specificity of IgG2 binding. Activation of protein kinase C with phorbol myristate acetate was used to determine the effect of cellular activation on expression of CR1. A greater percentage of neutrophils from normal calves bound C3b than did neutrophils from LAD-affected calves. Receptor expression was similar. Activation with phorbol myristate acetate resulted in increased expression of CR1 on neutrophils from normal and LAD-affected calves, but expression was almost twofold greater on neutrophils from normal calves. There was no difference between LAD-affected and normal calves in percentage of neutrophils that bound endogenous IgG and IgM. A greater percentage of neutrophils from normal calves bound exogenous IgM than did neutrophils from LAD-affected calves. Receptor expression for aIgG was greater on neutrophils from LAD-affected calves than on those from normal calves. Luminol-enhanced CL of neutrophils in response to IgG2 opsonized zymosan was not different between LAD-affected and normal calves. Results indicate increased binding and expression of Fc receptors for aIgG and decreased binding and expression for C3b and IgM on neutrophils from calves with LAD. Leukocyte adhesion deficiency may be compounded by added defects in the expression and binding of receptors for opsonins, such as C3b and IgM.
Показать больше [+] Меньше [-]Complement component C3b and immunoglobulin Fc receptors on neutrophils from calves with leukocyte adhesion deficiency.
1995
Worku M. | Paape M.J. | Di Carlo A. | Kehrli M.E. Jr. | Marquardt W.W.
Receptors for opsonins, such as complement component C3b (CR1) and immunoglobulins, Fc receptors, interact with adhesion glycoproteins in mediating immune functions. Defects in expression of the adhesion glycoproteins CD11/CD18 results in severely hampered in vitro and in vivo adherence-related functions of leukocytes. Little is known regarding the effect of leukocyte adhesion deficiency (LAD) on ligand binding and receptor expression. We investigated the binding and expression of CR1 and Fc receptors by bovine neutrophils isolated from dairy calves suffering from LAD, compared with clinically normal (hereafter referred to as normal) age-matched calves. Neutrophils were also assayed for endogenously bound IgG and IgM and for exogenous binding of C3b, IgG1, IgG2, IgM, and aggregated IgG (aIgG), using flow cytometry. Luminol-enhanced chemiluminescence (CL) production in response to IgG2 opsonized zymosan was studied, and specific inhibition of CL was used to determine the specificity of IgG2 binding. Activation of protein kinase C with phorbol myristate acetate was used to determine the effect of cellular activation on expression of CR1. A greater percentage of neutrophils from normal calves bound C3b than did neutrophils from LAD-affected calves. Receptor expression was similar. Activation with phorbol myristate acetate resulted in increased expression of CR1 on neutrophils from normal and LAD-affected calves, but expression was almost twofold greater on neutrophils from normal calves. There was no difference between LAD-affected and normal calves in percentage of neutrophils that bound endogenous IgG and IgM. A greater percentage of neutrophils from normal calves bound exogenous IgM than did neutrophils from LAD-affected calves. Receptor expression for aIgG was greater on neutrophils from LAD-affected calves than on those from normal calves.
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