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1.
Theriogenology ; 144: 1-7, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31881476

RESUMO

Kisspeptin (KP) is a hypothalamic neuropeptide that stimulates the secretion of gonadotropin releasing hormone. To determine the acute and chronic effects of KP on serum concentrations of luteinizing hormone (LH) and follicle stimulating hormone (FSH), prepubertal bull calves [12 ± 1 (SD) weeks of age; 96.5 ± 14.5 kg BW] were administered one of four treatments [0.0 (control; CON), 0.125 (L-KP), 0.25 (M-KP), or 0.5 (H-KP) µg of KP/kg BW/hour] by intravenous infusion for 76 h. Blood samples were collected every 15 min for the first (acute; 1-6 h; Day 1) and last (chronic; 71-76 h; Day 4) 6 h of the intravenous infusions. Serum concentrations of LH and FSH were determined by radioimmunoassay. For each day, effects of treatment, time, and interactions on LH and FSH concentrations and pulse parameters were analyzed using procedures for repeated measures with JMP Software (SAS Inst. Inc., Cary, NC). There was a treatment effect (P = 0.002) and a treatment × time interaction during Day 1 (P = 0.02) such that LH concentrations were greatest following administration of all doses of KP when compared to CON. However, there was no treatment effect (P = 0.57) or a treatment × time interaction during Day 4 (P = 0.20) on serum LH concentrations. There was a treatment by day interaction (P = 0.02) on mean serum FSH concentrations. Most notably, on Day 4 mean serum FSH concentrations during intravenous infusion of M-KP and H-KP doses were less than that of CON. There was a treatment by day interaction (P = 0.0054) on FSH pulse amplitude concentrations, such that intravenous infusion of all doses of KP on Day 4 decreased FSH pulse amplitudes. In conclusion, acute infusion of KP increased LH concentrations and chronic infusion of KP decreased FSH concentrations. Despite the potential suppression of the hypothalamic-pituitary-gonadal axis with chronic infusion of KP, there are likely applications of KP, KP analogs, or KP receptor agonists to hasten the onset of puberty in livestock.


Assuntos
Bovinos/fisiologia , Hormônio Foliculoestimulante/sangue , Kisspeptinas/farmacologia , Hormônio Luteinizante/sangue , Maturidade Sexual , Animais , Injeções Intravenosas , Kisspeptinas/administração & dosagem , Masculino
3.
J Am Vet Med Assoc ; 236(5): 558-61, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20187821

RESUMO

CASE DESCRIPTION: An adult sexually intact female Vietnamese potbellied pig was examined because of abdominal distention of 5 months' duration. CLINICAL FINDINGS: The pig was moderately anemic, and its abdomen was greatly distended. A freely movable abdominal mass was detected during palpation and ultrasonographic examination of the abdomen. Examination of abdominal and thoracic radiographs revealed faint, ill-defined, linear and curvilinear mineralized opacities in the region of the mass and that the gastrointestinal tract was displaced craniodorsally. Results of radiographic examination suggested that the cause of distention was a single abdominal mass (possibly a neoplasm). TREATMENT AND OUTCOME: Surgery was performed, and the mass, which was identified as the right ovary, was removed. The left ovary had a normal appearance, but it was also removed during surgery. The pig was administered a transfusion (314 mL of plasma and 296 mL of packed RBCs) before and during surgery. The mass, which accounted for approximately one-third of the pig's body weight, was identified histologically as an ovarian leiomyoma. CLINICAL RELEVANCE: Pigs can safely be administered a transfusion of RBCs and plasma. Ovarian tumors can be removed from Vietnamese potbellied pigs, which allows them to be used as pets or for reproduction when only 1 ovary is affected. Uterine masses in older sexually intact Vietnamese potbellied pigs are more common than are ovarian tumors; thus, complete ovariohysterectomy should be considered when the primary purpose of the pig is to serve as a pet.


Assuntos
Leiomioma/veterinária , Neoplasias Ovarianas/veterinária , Doenças dos Suínos/cirurgia , Animais , Transfusão de Sangue/veterinária , Eritrócitos , Feminino , Leiomioma/cirurgia , Neoplasias Ovarianas/cirurgia , Plasma , Suínos
4.
J Vet Diagn Invest ; 20(6): 827-30, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18987240

RESUMO

A pregnant 18-year-old Quarterhorse mare presented with fever, anorexia, tachycardia, tachypnea, and gastrointestinal hypermotility at day 68 of gestation. Potomac horse fever was diagnosed based on polymerase chain reaction (PCR) analysis of whole blood and a high antibody titer to Neorickettsia risticii. The mare made a rapid clinical recovery following antibiotic therapy, but aborted 98 days later. Necropsy on the aborted fetus revealed lymphohistiocytic colitis, lymphadenitis, myocarditis, and hepatitis. The placenta was grossly and histologically normal. Formalin-fixed lymph node, thymus, liver, and colon taken from the aborted fetus were positive by PCR for N. risticii DNA. Potomac horse fever is a common disease in horses that may result in delayed abortion. The microscopic lesions in the fetus are characteristic, and the diagnosis can be confirmed by PCR on formalin-fixed tissues.


Assuntos
Aborto Espontâneo/microbiologia , Infecções por Anaplasmataceae/veterinária , Doenças dos Cavalos/microbiologia , Neorickettsia risticii/isolamento & purificação , Aborto Espontâneo/patologia , Infecções por Anaplasmataceae/complicações , Infecções por Anaplasmataceae/patologia , Animais , Colo/patologia , Feminino , Cavalos , Inflamação/etiologia , Inflamação/veterinária , Fígado/patologia , Linfonodos/patologia , Neorickettsia risticii/genética , Placenta/microbiologia , Reação em Cadeia da Polimerase , Timo/patologia
5.
Langmuir ; 20(20): 8431-6, 2004 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-15379457

RESUMO

Natural systems excel in directing the synthesis of inorganic materials for various functional purposes. One of the best-studied systems is silica synthesis, as occurs in diatoms and marine sponges. Various biological and synthetic polymers have been shown to template and catalyze silica formation from silicic acid precursors. Here, we describe the use of poly-L-lysine to promote the synthesis of silica in neutral, aqueous solution and when immobilized onto a silicon support structure under similar conditions. Either reagent jetting or conventional photolithography techniques can be used to pattern the templating polymer. Spots created by reagent jetting led to the creation of silica structures in the shape of a ring that may be a result of the spotting process. Photolithographically defined poly-L-lysine spots led to thin laminate structures after exposure to a dilute aqueous silicic acid solution. The laminate structures were nanostructured and highly interconnected. Photolithographic patterning of (3-aminopropyl)trimethoxysilane, a reagent that mimics the lysine functional group, led to similar silica coatings even though low-molecular-weight materials do not rapidly promote silica synthesis in solution. This result highlights the importance of functional-group arrangement for templating and promoting the synthesis of inorganic materials. The described surface-patterning techniques offer a route to integrate conventional silicon-patterning technologies with biologically based material synthesis. Such combined fabrication techniques enable controlled assembly over multiple length scales and an approach to understanding interfacial silica synthesis, as occurs in natural systems.


Assuntos
Biomimética , Nanoestruturas/química , Polilisina/química , Dióxido de Silício/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Dióxido de Silício/síntese química , Propriedades de Superfície , Água/química
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