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1.
Artículo en Inglés | MEDLINE | ID: mdl-11440874

RESUMEN

Our understanding of insulin-like growth factor-I (IGF-I) in cervids has been limited mostly to its effects on antler development in red deer (Cervus elaphus), roe deer (Capreolus capreolus), fallow deer (Dama dama), and pudu (Pudu puda). Although IGF-I has been found to play a critical role in reproductive function of other mammals, its role in reproduction of deer is unknown. The objectives of the present study were to determine if serum levels of IGF-I change during the breeding season, assess whether age influences serum IGF-I, compare levels of IGF-I measured during and following the breeding season, and determine if IGF-I is associated with body and antler characteristics in free-ranging adult, male white-tailed deer (Odocoileus virginianus). We collected serum and morphometric data from hunter-harvested and captured white-tailed deer to investigate these objectives. Mean level of serum IGF-I during the breeding season was 63.6 ng/ml and was greatest in deer between 2.5 and 5.5 years old (57.4-79.9 ng/ml). Levels of serum IGF-I decreased by approximately 40% as the breeding season progressed, but levels were less in deer following the breeding season (34.6 ng/ml). Both body and antler size were associated positively with IGF-I when controlling for age. Serum testosterone was also associated positively with IGF-I. Levels of serum testosterone during the breeding season generally increased with age from 4.82 (1.5 years old) to 18.79 ng/dl (5.5 years old), but decreased thereafter. These data suggest that IGF-I may be an important hormone in breeding, male white-tailed deer.


Asunto(s)
Cruzamiento , Ciervos/fisiología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Testosterona/sangre , Envejecimiento , Animales , Cuernos de Venado/fisiología , Peso Corporal , Ciervos/sangre , Masculino
2.
Evolution ; 55(3): 616-25, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11327168

RESUMEN

Good-genes hypotheses predict that development of secondary sexual characters can be an honest advertisement of heritable male quality. We explored this hypothesis using a cervid model (adult, male white-tailed deer, Odocoileus virginianus) to determine whether antler development could provide an honest signal of a male's genetic quality and condition to adversaries. We compared antler, morphometric, hormonal, and parasitic data collected from hunter-harvested deer to characteristics of the Mhc-DRB (Odvi), the most widely studied gene of the major histocompatibility complex (MHC) in Artiodactyla. We detected associations between genetic characteristics at Odvi-DRB and antler development and body mass, suggesting that antler development and body mass may be associated with pathogen resistance in deer and thus may be an honest signal of genetic quality. We also detected associations between Odvi-DRB characteristics and serum testosterone during the breeding season, suggesting that certain MHC characteristics may help deer cope with stresses related to breeding activity. In addition, we observed a negative relationship between degree of antler development and overall abundance of abomasal helminths. Our observations provide support for the hypothesis that antler development in white-tailed deer is an honest signal of quality.


Asunto(s)
Cuernos de Venado/fisiología , Ciervos/genética , Complejo Mayor de Histocompatibilidad/genética , Abomaso/parasitología , Alelos , Animales , Peso Corporal/genética , ADN/genética , Ciervos/anatomía & histología , Ciervos/parasitología , Femenino , Complejo Mayor de Histocompatibilidad/fisiología , Masculino , Nematodos/crecimiento & desarrollo , Filogenia , Análisis de Regresión , Análisis de Secuencia de ADN , Testosterona/sangre
3.
Proc Biol Sci ; 268(1470): 891-8, 2001 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-11370961

RESUMEN

Secondary sexual characters have been hypothesized to signal male quality and should demonstrate a negative relationship between the size of the trait and degree of fluctuating asymmetry because they are costly to produce. We collected morphometric and antler data from 439 white-tailed deer (Odocoileus virginianus) in Oklahoma, USA, in order to determine whether measures of antler asymmetry follow the patterns predicted for sexually selected characters. Relative fluctuating asymmetry was negatively related to antler size for all deer and within age groups up to five and a half years of age. We did not detect an association between asymmetry and antler size among deer that were six and a half years or older. When categorizing deer by antler size, we found that deer with small antlers (< or = 33rd percentile) had greater levels of relative asymmetry than deer with large antlers (< or = 67th percentile). The relative asymmetry of antlers was negatively related to age and was greatest in deer that were one and a half years old. Relative asymmetry was also negatively related to carcass mass, inside spread, skull length and body length. These data suggest that asymmetry in the antlers of white-tailed deer may be a reliable signal of quality and, as such, may be important in maintaining honesty in intrasexual advertisements during the breeding season.


Asunto(s)
Cuernos de Venado/anatomía & histología , Ciervos/anatomía & histología , Ciervos/fisiología , Conducta Sexual Animal , Envejecimiento , Animales , Peso Corporal , Conducta de Elección , Femenino , Masculino , Oklahoma
4.
J Wildl Dis ; 36(2): 308-15, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10813613

RESUMEN

Capture-related mortality has been a notable risk in the handling of eastern wild turkey (Meleagris gallopavo silvestris). Our objective was to evaluate how environmental factors influence risk and identify physiological correlates that could be used to identify susceptible birds. During winter (January-March) 1995-97, 130 eastern wild turkey hens were captured in southeastern Oklahoma and radiocollared. Of those, 20 hens died < or =14 days of capture. Serum creatine kinase activity (CK; P < 0.01), body temperature (P < 0.01), processing time (P = 0.02), and ambient temperature (P < 0.01) showed a positive relationship with mortality that occurred within 14 days of capture. Plasma corticosterone concentration (P = 0.08) and relative humidity (P < 0.01) showed a negative relationship with mortalities that occurred within 14 days post-capture. Stepwise logistic regression selected CK activity, relative humidity, and ambient temperature as the best predictors of mortality within 14 days post-capture. Our data suggest that susceptible individuals may be identified from CK activity and that capture-related mortality may be minimized by establishing guidelines of when to curtail capture operations based on various weather conditions.


Asunto(s)
Animales Salvajes/fisiología , Mortalidad , Pavos/fisiología , Animales , Aspartato Aminotransferasas/sangre , Temperatura Corporal , Corticosterona/sangre , Creatina Quinasa/sangre , Femenino , Manejo Psicológico , Humedad , Modelos Logísticos , Factores de Riesgo , Temperatura , Factores de Tiempo
5.
J Toxicol Sci ; 24 Suppl 1: 7-18, 1999 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-10637777

RESUMEN

Gadobenate dimeglumine formulation (E7155) was given by single intravenous injection to 4-5 month-old beagle dogs at doses of 2 or 6 mmol/kg. Treatment was followed by a 14-day observation period in order to evaluate the test article's toxicity. The male and female dogs at 6 mmol/kg vomited and showed reddened gums and ears as clinical signs. One male dog at 6 mmol/kg was euthanized approximately 23 hr after administration due to its very poor clinical condition, which included an unwillingness to move, pale gums and weak pulse. Body weight was decreased at 6 mmol/kg, and also slightly at 2 mmol/kg. Decreased food consumption was noted both at 2 and 6 mmol/kg. Hematology for the euthanized male at 6 mmol/kg showed increases in the total white blood cell count, packed cell volume, hemoglobin and red cell count and a decrease in the platelet count. Biochemistry showed a dose-related increase in alkaline phosphatase, GPT and GOT at 2 and 6 mmol/kg. Males and females at 6 mmol/kg showed increases in bilirubin, calcium and urea, and a reduction in glucose. Females at 6 mmol/kg also showed a reduction in total protein. Urinalysis showed an increase in pH at 2 mmol/kg and above. For females at 6 mmol/kg, an increase in urine volume and a decrease in specific gravity and osmolality were noted. An increase in relative liver and kidney weights was recorded for males and females dosed at 6 mmol/kg. For the euthanized male at 6 mmol/kg, postmortem examination revealed a pale liver with rounded edges and an accentuated lobular pattern, and dark material on the gastro-intestinal mucosal surface. In macroscopic pathology, the male at 6 mmol/kg revealed single liver cell necrosis, minimal early hyperplasia in small biliary ductules, inflammatory cells in the sinusoidal and portal tracts, centrilobular inflammatory cells, diffuse vacuolation of the hepatocytes and sinusoidal dilatation in the liver, and cortical tubular vacuolation in the kidneys. In the female dog treated at 6 mmol/kg, hyperplasia in the small biliary ductules, inflammatory cells in the portal tracts, diffuse vacuolation of hepatocytes and sinusoidal dilatation were seen in the liver, and increases in the severity of cortical tubular basophilia, cortical tubular dilatation and cortical tubular casts were detected in the kidney. Based on these results, the lethal dose of E7155 was set at 6 mmol/kg. It is also concluded that a dose of 2 mmol/kg was tolerated in the beagle dog after a single injection followed by a 14-day observation period.


Asunto(s)
Medios de Contraste/toxicidad , Gadolinio/toxicidad , Meglumina/análogos & derivados , Compuestos Organometálicos/toxicidad , Animales , Análisis Químico de la Sangre , Peso Corporal/efectos de los fármacos , Perros , Ingestión de Alimentos/efectos de los fármacos , Femenino , Pruebas Hematológicas , Inyecciones Intravenosas , Dosificación Letal Mediana , Imagen por Resonancia Magnética , Masculino , Meglumina/toxicidad , Urinálisis
6.
J Toxicol Sci ; 24 Suppl 1: 19-39, 1999 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-10637778

RESUMEN

A 4-week repeated dose toxicity study of gadobenate dimeglumine formulation (E7155) was conducted in Sprague-Dawley rats to assess its non-clinical safety. E7155 was administered intravenously at doses of 0.3, 1.0 and 3.0 mmol/kg/day to male and female rats once a day during 4 weeks. The reversibility of toxicity was evaluated during a 4-week recovery period at 3.0 mmol/kg/day. At 0.3 mmol/kg/day and higher, vacuolation of the cortical epithelium was seen in the kidneys and an increase in the incidence of local damage at the injection sites. In the 1.0 and 3.0 mmol/kg/day male and female groups, scabbing/ulceration of the tail at the injection sites, macroscopic pale/thickened fundic mucosa in the stomachs, vacuolation of the urinary bladder, and mucosal mineralization with epithelial hyperplasia of the glandular stomach were found. In the 1.0 and 3.0 mmol/kg/day male group and 3.0 mmol/kg/day female group, increases of water consumption and urinary potassium excretion, increased kidney weight and enlargement of the kidneys were observed. In the 3.0 mmol/kg/day male and female group, hepatocyte necrosis with inflammatory cells in the liver and epithelial degranulation in the interlobular ducts of the salivary glands were found. In addition, in the 3.0 mmol/kg/day male group, increases in plasma sodium and decreases of urinary sodium and chloride excretion, and degenerative changes in the testes and epididymides were observed. After the 4-week recovery period, except for an increase in urinary potassium excretion, increased kidney weights and changes in the testes and epididymides, all of the above findings had complete or partial recovery. Vacuolation of renal tubular cells was common, expected, and known as an adaptive change of treatment with hypertonic solutions, and an increase in the incidence of local damage at the injection sites was due to irritation by repeated intravenous dosing with hypertonic solutions. Therefore, these changes were not toxic changes. In conclusion, the dose level of 0.3 mmol/kg/day should be regarded as the No Observed Adverse Effect Level (NOAEL) after repeated administration of E7155 in rats.


Asunto(s)
Medios de Contraste/toxicidad , Gadolinio/toxicidad , Meglumina/análogos & derivados , Compuestos Organometálicos/toxicidad , Animales , Análisis Químico de la Sangre , Peso Corporal/efectos de los fármacos , Ingestión de Líquidos/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Ojo/efectos de los fármacos , Femenino , Pruebas Hematológicas , Inyecciones Intravenosas , Imagen por Resonancia Magnética , Masculino , Meglumina/toxicidad , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Factores de Tiempo , Urinálisis
7.
J Toxicol Sci ; 24 Suppl 1: 79-87, 1999 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-10637782

RESUMEN

Gadobenate dimeglumine formulation (E7155) was daily administered by intravenous injection at 0.3, 0.9 or 2.0 mmol/kg/day to mated NZW female rabbits (20/group) to assess the effect on embryo-fetal development. Treatment with 2.0 mmol/kg/day caused initial, notable loss of body weight and reduction in food consumption. Slightly reduced body weight gain and food intake were recorded at 0.9 mmol/kg/day. There were no obvious adverse effects in dams given E7155 at 0.3 mmol/kg/day. There was a slightly higher incidence of early intrauterine deaths at 0.9 and 2.0 mmol/kg/day. Morphological examination of fetuses at 2.0 mmol/kg/day revealed small eye/microphthalmia and/or retinal irregularities in three fetuses from three separate litters. There was also an increase in the incidence of additional and/or fused sternebral centres and 20-thoracolumbar vertebrae at this dosage. From these results, the No Observed Adverse Effect Level (NOAEL) for general toxicity of dams and embryo-fetal development was 0.3 mmol/kg/day.


Asunto(s)
Medios de Contraste/toxicidad , Embrión de Mamíferos/efectos de los fármacos , Feto/efectos de los fármacos , Gadolinio/toxicidad , Meglumina/análogos & derivados , Compuestos Organometálicos/toxicidad , Teratógenos , Anomalías Inducidas por Medicamentos/etiología , Animales , Peso Corporal/efectos de los fármacos , Femenino , Muerte Fetal/inducido químicamente , Inyecciones Intravenosas , Imagen por Resonancia Magnética , Meglumina/toxicidad , Conejos
8.
Arzneimittelforschung ; 38(11): 1625-9, 1988 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3214447

RESUMEN

S-Adenosyl-L-methionine sulphate-p-toluene sulphonate (ademetionine, SAMe), a donor of methyl groups, was examined for effects upon embryofoetal toxicity following both premating treatment and treatment during pregnancy and for peri- and post-natal toxicity in the rat at dosages of 0, 100, 200 and 400 mg/kg/d SAMe ion by subcutaneous or intravenous administration. Embryofoetal toxicity was also examined in the New Zealand White rabbit at dosages of 0, 10, 20 and 40 mg/kg/d SAMe by intravenous administration. Treatment was considered to be without adverse effect upon any of the reproductive parameters examined on either F0 or on the untreated F1 generations. There was no indication that treatment adversely affected the litter parameters including the incidences of malformations, anomalies and skeletal variants. Some slight changes in the activity of the F1 females derived from F0 animals given 400 mg/kg/d were considered to be of minimal importance. In contrast to the above, adverse effects upon the parents were noted at 400 mg/kg/d including local tissue reaction at the injection sites and retardation of body weight gain. In the intravenous studies some rigidity and dyspnoea were noted following administration. Following subcutaneous premating treatment there was also evidence of histopathological change to the kidney of the female rat. Increased water consumption was noted in this latter study and amongst females rearing offspring in the embryo foetal toxicity study in which the compound was administered intravenously. At the lower dosages administered to the rat some local tissue reaction was evident as was some retardation of body weight gain, minimal at the lowest intravenous dose.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Anomalías Inducidas por Medicamentos , S-Adenosilmetionina/toxicidad , Animales , Peso al Nacer/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Ingestión de Líquidos/efectos de los fármacos , Femenino , Fertilidad/efectos de los fármacos , Inyecciones Intravenosas , Inyecciones Subcutáneas , Tamaño de la Camada/efectos de los fármacos , Masculino , Tamaño de los Órganos/efectos de los fármacos , Conejos , Ratas , S-Adenosilmetionina/administración & dosificación
10.
Toxicol Lett ; 9(1): 55-64, 1981 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7302974

RESUMEN

Lentinan, a polysaccharide [(1 leads to 3)-beta-D-glucan], at 0.01, 0.10 or 1.0 mg/kg/day, was administered i.v. once daily to male rats for 9 weeks and to females for 2 weeks before mating. Some animals continued to be treated until they were killed during gestation: others were killed on day 21 post partum. Selected animals of the F1 generation were retained without further treatment, to provide F2 offspring. Reactions to treatment were generally dose-related and included bruising and cutaneous lesions of the tail and swelling and discolouration of the pinnae. In males given 1.0 mg/kg/day there was a clear evidence of gonadal damage and impairment of reproductive capacity; this effect was less marked at 0.1 mg/kg/day and much reduced at 0.01 mg/kg/day. However, the reproductive performance of the selected F1 pups did not appear to have been affected by the treatment of the F0 parents at any dosage. In animals of both sexes there was a dose-related enlargement of the spleen, with evidence of macrophage infiltration.


Asunto(s)
Fertilidad/efectos de los fármacos , Lentinano/toxicidad , Polisacáridos/toxicidad , Reproducción/efectos de los fármacos , Anomalías Inducidas por Medicamentos/etiología , Animales , Peso al Nacer/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Femenino , Masculino , Tamaño de los Órganos/efectos de los fármacos , Embarazo , Ratas
11.
Toxicol Lett ; 9(1): 65-9, 1981 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7302975

RESUMEN

Lentinan at 0.1, 0.3 and 1.0 mg/kg/day was administered i.v. to the New Zealand White rabbit, once daily, on days 6--18 of gestation. There were no significant treatment-related effects of post implantation loss, mean litter size and weight, mean foetal weight or the incidence of minor skeletal or visceral anomalies.


Asunto(s)
Lentinano/toxicidad , Polisacáridos/toxicidad , Preñez/efectos de los fármacos , Anomalías Inducidas por Medicamentos/etiología , Animales , Peso Corporal/efectos de los fármacos , Embrión de Mamíferos/efectos de los fármacos , Femenino , Feto/efectos de los fármacos , Embarazo , Conejos , Bazo/efectos de los fármacos
12.
J Pharm Sci ; 67(6): 857-9, 1978 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-660476

RESUMEN

Secondary disulfonamides and secondary tetrasulfondiamides were prepared for antineoplastic activity testing. For the disulfonamides, one alkyl series (n-butyl), three aralkyl series (benzyl, phenethyl, and phenpropyl), and one diaralkyl series (diphenpropyl) were prepared. Two series of tetrasulfondiamides were made from diamines, one in which the central methylene chain was varied from four to six and another using the tetrasubstituted sulfonyl derivative of xylylenediamine. Thirteen final compounds were synthesized. Ten of these compounds and four intermediates have not been reported previously. Preliminary screening results for the final compounds are given.


Asunto(s)
Alquilantes/síntesis química , Sulfonamidas/síntesis química , Animales , Ratones , Ratas , Sulfonamidas/farmacología
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