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1.
Cryobiology ; 62(1): 32-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21145884

RESUMO

The perinuclear theca (PT) is a cytoskeletal structure that surrounds the mammal sperm nucleus which must be disrupted once the sperm has penetrated the oocyte to permit normal chromatin decondensation and formation of male pronucleus. F-actin is a thermo sensitive protein found in the equatorial segment which is involved in the stability of PT. It has been reported that cryopreservation induces alterations in nuclear decondensation of spermatozoa, which have been interpreted as an over condensation. The aims of the present study were identified the presence of changes in sperm sPT integrity of frozen-thawed boar spermatozoa and its effect in sperm nuclei decondensation; and whether changes in the actin cytoskeleton are involved using an in vitro model to test probably differences in a chemical decondensation (DTT/heparin) between fresh (FS) and frozen-thawed (TS) spermatozoa. Results showed an increase on sPT damage in TS (P<0.001), and significant changes in sperm chromatin nuclear decondensation (P<0.05). In same way differences on the swelling degree was found assessed by measures in equatorial region of head sperm (P<0.05). Evaluation with rodamine-labeled actin (0.2µM) showed two different patterns with differences in percentages before and after cryopreservation (P<0.001). F-actin stabilization constrained the equatorial segment of FS while this was not observed in TS. The data showed that the presence of early changes in sPT integrity and changes in the F-actin localization on TS may suggest the participation in F-actin in decondensation process and probably that the disruption of actin-PT interaction during freezing-thawing process could have far-reaching consequences for the subsequent fertility of spermatozoa.


Assuntos
Actinas/metabolismo , Cromatina/ultraestrutura , Criopreservação/métodos , Congelamento/efeitos adversos , Preservação do Sêmen/efeitos adversos , Cabeça do Espermatozoide/ultraestrutura , Sus scrofa , Animais , Citoesqueleto/fisiologia , Tomografia com Microscopia Eletrônica/métodos , Masculino , Sêmen/citologia , Sêmen/fisiologia , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Cabeça do Espermatozoide/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Espermatozoides/ultraestrutura
2.
Res Vet Sci ; 85(2): 359-67, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18031776

RESUMO

"Blue eye disease" is a viral infection of swine endemic in Mexico, which produces fatal encephalitis accompanied by respiratory signs and corneal opacity in suckling piglets. An atypical blue eye disease outbreak presented high rates of neurological signs in fattening and adult pigs from 2000 to 2003. In order to identify the basis of increased neurovirulence, the hemagglutinin-neuraminidase (HN) gene of several porcine rubulavirus isolates were sequenced and compared with that of La Piedad Michoacan virus and other isolates that did not produce neurological disorders in weaned pigs. Nine amino acid mutations distinguished the high neurovirulent PAC6-PAC9 viruses, whereas five mutations characterized the low neurovirulent PAC2 and PAC3 viruses. HN protein three-dimensional models showed that the main conformation and functional domains were preserved, although substitutions A223T and A291D occurred in PAC2 and PAC3 viruses, as well as A511K and E514K presented in PAC6-PAC9 viruses considerably modified the properties of the HN protein surface. The increased positive charge of the HN protein of PAC6-PAC9 viruses seems to be associated with their increased neurovirulence.


Assuntos
Proteína HN/genética , Doenças do Sistema Nervoso/veterinária , Infecções por Rubulavirus/veterinária , Rubulavirus/genética , Doenças dos Suínos/virologia , Sequência de Aminoácidos , Animais , Surtos de Doenças/veterinária , México/epidemiologia , Modelos Moleculares , Dados de Sequência Molecular , Doenças do Sistema Nervoso/epidemiologia , Doenças do Sistema Nervoso/virologia , Filogenia , Conformação Proteica , Rubulavirus/classificação , Infecções por Rubulavirus/epidemiologia , Infecções por Rubulavirus/virologia , Suínos , Doenças dos Suínos/epidemiologia
3.
Theriogenology ; 64(9): 1889-97, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15963559

RESUMO

Oxytocin and vetrabutin chlorhydrate (VC) are used to reduce the duration of farrowing in swine. The objective of the present study was to evaluate the use of these products on intra-partum stillbirth (IPS) rate and asphyxia. At the onset of parturition, sows (n=180) were allocated to receive 2 mL of saline (control group), oxytocin (40 IU i.m.) or 100mg of VC per 60 kg of body weight, with all treatments given i.m. Oytocin-treated sows had a higher number of IPS than the VC and Control groups (means, 1.2, 0.8 and 0.6, respectively; P<0.001), and the highest percentage of ruptured umbilical cords (76.0, 9.4 and 37.5%; P<0.003). There were differences among groups for duration of farrowing (means, 163.0, 211.2 and 306.9 min in the oxytocin, VC and control groups; P<0.001), interval between piglets (13.9, 19.2 and 28.1 min; P<0.001), and in IPS, the incidence of ruptured umbilical cords was 76.0, 9.4 and 37.5% (P<0.003) and absence of a fetal heartbeat was 53.3, 16.9 and 12.5% (P<0.05). Although oxytocin decreased both duration of farrowing and interval between piglets by approximately 50% relative to control sows, it resulted in a significantly higher rate of IPS, in association with a much higher incidence of ruptured umbilical cord and absence of a fetal heartbeat. Treatment with VC reduced farrowing duration by approximately 1.5h, with an IPS rate that was not significantly different from controls but significantly lower than that of oxytocin-treated sows.


Assuntos
Asfixia/veterinária , Ocitocina/efeitos adversos , Natimorto/veterinária , Doenças dos Suínos/epidemiologia , Animais , Asfixia/epidemiologia , Asfixia/etiologia , Feminino , Parto , Gravidez , Ruptura Espontânea/veterinária , Suínos , Doenças dos Suínos/etiologia , Fatores de Tempo , Cordão Umbilical , Contração Uterina/efeitos dos fármacos , Contração Uterina/fisiologia
4.
G E N ; 46(4): 341-6, 1992.
Artigo em Espanhol | MEDLINE | ID: mdl-1340842

RESUMO

Alagille's syndrome or arteriohepatic dysplasia has been described in Cuba in nine patients between nine months and 12 years of age (8 males and one female). Among the clinical features we found five major abnormalities: chronic cholestasis with neonatal jaundice (9/9), peculiar facies (9/9), peripheral pulmonary artery hypoplasia associated with cardiac murmur (6/9), butter-fly-like arch defects (4/9), and posterior embryotoxon (6/7). Two children had a severe xanthomatosis. Laparoscopy showed green hepatomegaly depending on the degree of cholestasis, and only one patient had incipient signs of micronodular cirrhosis. Liver histology showed a paucity of interlobular bile ducts. Survival was of 60%. One patient survived more than 30 years. Four patients died of liver carcinoma (unique report in infants), broncho-pneumonia, acute renal failure, and sudden death respectively. Among the minor features were mental retardation (5/9), a peculiar voice (3/9), growth retardation observed in some of our patients. This is the first report on Alagille's syndrome in Latin America, because so far reports have come only from Europe and North America.


Assuntos
Síndrome de Alagille/diagnóstico , Síndrome de Alagille/mortalidade , Síndrome de Alagille/patologia , Biópsia por Agulha , Criança , Pré-Escolar , Cuba/epidemiologia , Feminino , Humanos , Lactente , Laparoscopia , Fígado/patologia , Masculino
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