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1.
Am J Transplant ; 17(10): 2687-2695, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28390109

RESUMO

Vascularized composite allograft (VCA) transplantation has emerged as a groundbreaking surgical intervention to return identity and function following traumatic injury, congenital deformity, or disfigurement. While public attitudes toward traditional organ/tissue donation are favorable, little is known about attitudes toward VCA donation and transplantation. A survey was conducted of 1485 U.S. residents in August 2016 to assess VCA donation attitudes. Participants also completed the Revised Health Care System Distrust Scale. Most respondents were willing to donate hands/forearms (67.4%) and legs (66.8%), and almost half (48.0%) were willing to donate the face. Three-quarters (74.4%) of women were willing to donate the uterus; 54.4% of men were willing to donate the penis. VCA donation willingness was more likely among whites and Hispanics (p < 0.001), registered organ/tissue donors (p < 0.001), and those with less health care system distrust (p < 0.001) and media exposure to VCA transplantation (p = 0.003). Many who opposed VCA donation expressed concerns about psychological discomfort, mutilation, identity loss, and the reaction of others to seeing familiar body parts on a stranger. Attitudes toward VCA donation are favorable overall, despite limited exposure to VCA messaging and confusion about how VCA donation occurs. These findings may help guide the development and implementation of VCA public education campaigns.


Assuntos
Atitude Frente a Saúde , Aloenxertos Compostos , Transplante de Órgãos , Opinião Pública , Obtenção de Tecidos e Órgãos , Feminino , Humanos , Masculino , Inquéritos e Questionários , Transplante Homólogo , Estados Unidos
2.
Am J Transplant ; 16(1): 278-86, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26484950

RESUMO

Innovative deceased donor intervention strategies have the potential to increase the number and quality of transplantable organs. Yet there is confusion over regulatory and legal requirements, as well as ethical considerations. We surveyed transplant surgeons (n = 294), organ procurement organization (OPO) professionals (n = 83), and institutional review board (IRB) members (n = 317) and found wide variations in their perceptions about research classification, risk assessment for donors and organ transplant recipients, regulatory oversight requirements, and informed consent in the context of deceased donor intervention research. For instance, when presented with different research scenarios, IRB members were more likely than transplant surgeons and OPO professionals to feel that study review and oversight were necessary by the IRBs at the investigator, donor, and transplant center hospitals. Survey findings underscore the need to clarify ethical, legal, and regulatory requirements and their application to deceased donor intervention research to accelerate the pace of scientific discovery and facilitate more transplants.


Assuntos
Pesquisa Biomédica/ética , Comitês de Ética em Pesquisa , Transplante de Órgãos/ética , Doadores de Tecidos/ética , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/organização & administração , Gestão da Qualidade Total , Cadáver , Humanos , Transplante de Órgãos/legislação & jurisprudência , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Cirurgiões , Inquéritos e Questionários , Doadores de Tecidos/legislação & jurisprudência , Obtenção de Tecidos e Órgãos/ética , Obtenção de Tecidos e Órgãos/legislação & jurisprudência
3.
Am J Transplant ; 16(6): 1707-14, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26813036

RESUMO

The Organ Procurement and Transplantation Network (OPTN) Deceased Donor Potential Study, funded by the Health Resources and Services Administration, characterized the current pool of potential deceased donors and estimated changes through 2020. The goal was to inform policy development and suggest practice changes designed to increase the number of donors and organ transplants. Donor estimates used filtering methodologies applied to datasets from the OPTN, the National Center for Health Statistics, and the Agency for Healthcare Research and Quality and used these estimates with the number of actual donors to estimate the potential donor pool through 2020. Projected growth of the donor pool was 0.5% per year through 2020. Potential donor estimates suggested unrealized donor potential across all demographic groups, with the most significant unrealized potential (70%) in the 50-75-year-old age group and potential Donation after Circulatory Death (DCD) donors. Actual transplants that may be realized from potential donors in these categories are constrained by confounding medical comorbidities not identified in administrative databases and by limiting utilization practices for organs from DCD donors. Policy, regulatory, and practice changes encouraging organ procurement and transplantation of a broader population of potential donors may be required to increase transplant numbers in the United States.


Assuntos
Morte Encefálica , Política de Saúde , Transplante de Órgãos , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Cadáver , Criança , Pré-Escolar , Bases de Dados Factuais , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estados Unidos , United States Health Resources and Services Administration , Adulto Jovem
4.
Am J Transplant ; 14(8): 1740-3, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24840545

RESUMO

A policy proposal relating to transplantation of deceased donor organs into nonresidents of the United States was jointly sponsored by the Organ Procurement and Transplantation Network (OPTN)/United Network for Organ Sharing (UNOS) International Relations and Ethics Committees and approved by the OPTN/UNOS Board in June 2012. The proposal followed prior acceptance by the Board of the definitions of "travel for transplantation" and "transplant tourism" and the introduction in March 2012 of revised data collection categories for transplant candidates who are neither citizens nor residents. The most important aspect of the new policy concerns replacement of the previous so-called "5% rule" with the review of all residency and citizenship data and the preparation of a public annual report. The new policy does not prohibit organ transplantation in nonresidents. However, the policy and public data report will ensure transparency and support transplant center responsibility to account for their practices. Since the adoption of the policy, the first 19 months of data show that less than 1% of new deceased donor waitlist additions and less than 1% of transplantation recipients were non-US citizen/nonresidents candidates who traveled to the United States for purposes of transplantation. By adopting this policy, the US transplant community promotes public trust and serves as an example to the international transplant community.


Assuntos
Transplante de Órgãos/normas , Obtenção de Tecidos e Órgãos/métodos , Obtenção de Tecidos e Órgãos/normas , Política de Saúde , Humanos , Turismo Médico , Doadores de Tecidos , Estados Unidos , Listas de Espera
5.
Am J Transplant ; 13(7): 1636-42, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23758835

RESUMO

Case reports of kidney transplantation using HIV-positive (HIV+) donors in South Africa and advances in the clinical care of HIV+ transplant recipients have drawn attention to the legal prohibition of transplanting organs from HIV+ donors in the United States. For HIV+ transplant candidates, who face high barriers to transplant access, this prohibition violates beneficence by placing an unjustified limitation on the organ supply. However, transplanting HIV+ organs raises nonmaleficence concerns given limited data on recipient outcomes. Informed consent and careful monitoring of outcome data should mitigate these concerns, even in the rare circumstance when an HIV+ organ is intentionally transplanted into an HIV-negative recipient. For potential donors, the federal ban on transplanting HIV+ organs raises justice concerns. While in practice there are a number of medical criteria that preclude organ donation, only HIV+ status is singled out as a mandated exclusion to donation under the National Organ Transplant Act (NOTA). Operational objections could be addressed by adapting existing approaches used for organ donors with hepatitis. Center-specific outcomes should be adjusted for HIV donor and recipient status. In summary, transplant professionals should advocate for eliminating the ban on HIV+ organ donation and funding studies to determine outcomes after transplantation of these organs.


Assuntos
Ética Médica , Soropositividade para HIV , Transplante de Órgãos , Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Humanos , Transplante de Órgãos/ética , Transplante de Órgãos/etnologia , Transplante de Órgãos/métodos , Fatores de Risco , Doadores de Tecidos/ética , Doadores de Tecidos/legislação & jurisprudência , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/ética , Obtenção de Tecidos e Órgãos/legislação & jurisprudência , Obtenção de Tecidos e Órgãos/métodos
6.
Nat Genet ; 27(2): 156-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11175782

RESUMO

Spontaneously hypertensive rats (SHR) display several features of the human insulin-resistance syndromes. Cd36 deficiency is genetically linked to insulin resistance in SHR. We show that transgenic expression of Cd36 in SHR ameliorates insulin resistance and lowers serum fatty acids. Our results provide direct evidence that Cd36 deficiency can promote defective insulin action and disordered fatty-acid metabolism in spontaneous hypertension.


Assuntos
Antígenos CD36/genética , Hipertensão/genética , Resistência à Insulina/genética , Animais , Animais Geneticamente Modificados , Antígenos CD36/biossíntese , Ácidos Graxos/sangue , Teste de Tolerância a Glucose , Ratos , Ratos Endogâmicos SHR
7.
Nat Genet ; 21(1): 76-83, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9916795

RESUMO

The human insulin-resistance syndromes, type 2 diabetes, obesity, combined hyperlipidaemia and essential hypertension, are complex disorders whose genetic basis is unknown. The spontaneously hypertensive rat (SHR) is insulin resistant and a model of these human syndromes. Quantitative trait loci (QTLs) for SHR defects in glucose and fatty acid metabolism, hypertriglyceridaemia and hypertension map to a single locus on rat chromosome 4. Here we combine use of cDNA microarrays, congenic mapping and radiation hybrid (RH) mapping to identify a defective SHR gene, Cd36 (also known as Fat, as it encodes fatty acid translocase), at the peak of linkage to these QTLs. SHR Cd36 cDNA contains multiple sequence variants, caused by unequal genomic recombination of a duplicated ancestral gene. The encoded protein product is undetectable in SHR adipocyte plasma membrane. Transgenic mice overexpressing Cd36 have reduced blood lipids. We conclude that Cd36 deficiency underlies insulin resistance, defective fatty acid metabolism and hypertriglyceridaemia in SHR and may be important in the pathogenesis of human insulin-resistance syndromes.


Assuntos
Antígenos CD36/metabolismo , Ácidos Graxos/metabolismo , Glucose/metabolismo , Hipertensão/metabolismo , Resistência à Insulina/genética , Glicoproteínas de Membrana/genética , Transportadores de Ânions Orgânicos , Animais , Sequência de Bases , Membrana Celular/metabolismo , Mapeamento Cromossômico , DNA Complementar , Ácidos Graxos não Esterificados/metabolismo , Feminino , Deleção de Genes , Duplicação Gênica , Expressão Gênica , Ligação Genética , Variação Genética , Humanos , Masculino , Glicoproteínas de Membrana/fisiologia , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Característica Quantitativa Herdável , Ratos , Ratos Endogâmicos SHR , Triglicerídeos/metabolismo
10.
J Exp Med ; 158(1): 1-8, 1983 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-6345713

RESUMO

Lethally irradiated rats treated with cyclosporin A (CsA) for 20-40 d develop classic graft-versus-host disease (GVHD) when reconstituted with syngeneic or autologous bone marrow, upon discontinuation of CsA, whereas normal rats do not. Syngeneic GVHD may be transferred to irradiated but not normal syngeneic recipients. Normal spleen cells fail to prevent the development or adoptive transfer of syngeneic GVHD.


Assuntos
Transplante de Medula Óssea , Ciclosporinas/uso terapêutico , Doença Enxerto-Hospedeiro/prevenção & controle , Animais , Medula Óssea/efeitos da radiação , Ciclosporinas/administração & dosagem , Feminino , Doença Enxerto-Hospedeiro/patologia , Ratos , Ratos Endogâmicos Lew , Baço/citologia , Baço/transplante , Transplante Homólogo , Transplante Isogênico
13.
Reprod Fertil Dev ; 19(4): 521-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17524296

RESUMO

Artificial insemination of brushtail possums (Trichosurus vulpecula) is being developed as an assisted breeding model for endangered marsupials, as well as a bioassay for testing fertility control vaccines to manage overabundant populations. Procedures were optimised in animals superovulated with pregnant mare serum gonadotrophin (PMSG) and porcine luteinising hormone (pLH). Of three intervals examined, yields were maximal following uterine insemination at 27-29.5 h after pLH treatment (four eggs, two to three embryos per female). Compared with no insemination, uterine-inseminated animals ovulated 30-36 h rather than 28-34 h after pLH treatment. For the vaginal route, yields were maximal following insemination at 10-13 h after pLH treatment (six to seven eggs, four embryos per female) than at five other intervals, and when using acclimatised females during the autumn breeding season. This protocol was suitable for testing fertility control vaccines in April-June and was influenced by the housing location of animals, the presence of an active corpus luteum and PMSG batch, but not other factors (year of trial, Freund's adjuvant treatment, changes in bodyweight, dose of PMSG kg(-1)). Embryos developed to the eight- to 16-cell or unilaminar blastocyst stage after uterine or vaginal insemination, respectively. With the timing of artificial insemination optimised, new methods to synchronise or induce oestrus and ovulation are required to achieve year-round testing of fertility control vaccines or birth of offspring.


Assuntos
Gonadotropinas Equinas/farmacologia , Inseminação Artificial/métodos , Hormônio Luteinizante/farmacologia , Superovulação , Trichosurus/fisiologia , Animais , Desenvolvimento Embrionário , Feminino , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Indução da Ovulação/métodos , Gravidez , Suínos , Fatores de Tempo , Útero/fisiologia , Vacinas Anticoncepcionais/administração & dosagem , Vacinas Anticoncepcionais/antagonistas & inibidores , Vagina/fisiologia
14.
Diabetes ; 49(12): 2222-6, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11118030

RESUMO

Insulin resistance is of pathogenic importance in several common human disorders including type 2 diabetes, hypertension, obesity and hyperlipidemia, but the underlying mechanisms are unknown. The spontaneously hypertensive rat (SHR) is a model of these human insulin resistance syndromes. Quantitative trait loci (QTLs) for SHR defects in glucose and fatty acid metabolism, hypertriglyceridemia, and hypertension map to a single region on rat chromosome 4. Genetic analysis of an SHR derived from a National Institutes of Health colony led to the identification of a causative mutation in the SHR Cd36. We have investigated glucose and fatty acid metabolism in the stroke-prone SHR (SHRSP). We demonstrate defects in insulin action on 2-deoxy-D-glucose transport (SHRSP 3.3 +/- 1.5 vs. 21.0 +/- 7.4 pmol x min(-1) x [20 microl packed cells](-1), SHRSP vs. WKY, respectively, P = 0.01) and inhibition of catecholamine-stimulated lipolysis (P < 0.05 at all concentrations of insulin) in adipocytes isolated from SHRSP. In contrast, basal levels of catecholamine-stimulated nonesterified free fatty acid (NEFA) release and plasma levels of NEFA are similar in SHRSP and WKY. These results are in agreement with the data on the SHR.4 congenic strain, which suggested that the QTL containing Cd36 mutations accounted for the entire defect in basal catecholamine action but only for approximately 40% of the SHR defect in insulin action. In the SHR, both abnormalities appear consequent of defective Cd36 expression. Because Cd36 sequence and expression are apparently normal in SHRSP, it is likely that the molecular mechanism for defective insulin action in this strain is caused by a gene(s) different than Cd36.


Assuntos
Antígenos CD36/genética , Predisposição Genética para Doença , Resistência à Insulina/genética , Ratos Endogâmicos SHR/genética , Acidente Vascular Cerebral/genética , Adipócitos , Animais , Transporte Biológico , Catecolaminas/fisiologia , Desoxiglucose/farmacocinética , Ácidos Graxos/metabolismo , Deleção de Genes , Glucose/metabolismo , Insulina/fisiologia , Lipólise/efeitos dos fármacos , Masculino , Mutação/genética , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos WKY
15.
Biochem Pharmacol ; 45(6): 1235-41, 1993 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-8466544

RESUMO

We have investigated the effect of malaria infection with the rodent parasite Plasmodium berghei and fever induced by Escherichia coli endotoxin on the metabolism of phenacetin to paracetamol by rat liver microsomes from young (4 weeks old) male Wistar rats (N = 5 in control and fever groups; N = 10 in malaria-infected group). Following determination of % parasitaemia, the malaria-infected group was divided into a low parasitaemia subgroup (N = 5; mean % parasitaemia = 9.87 +/- 2.6) and a high parasitaemia subgroup (N = 5; mean % parasitaemia = 36.6 +/- 8.1). The control group received normal saline. Total microsomal protein was not significantly affected by fever or malaria infection while cytochrome P450 levels were reduced by approximately 50% in the high parasitaemia subgroup, 20% in the low parasitaemia subgroup and 20% in the endotoxin-treated group. Phenacetin-O-deethylation kinetics were biphasic in both control and malaria-infected rats, but monophasic in endotoxin-treated rats. Total apparent intrinsic clearance (CL(int),total; calculated as Vmax/Km; Vmax is maximum velocity, Km is Michaelis constant) of phenacetin was reduced approximately 6-fold in low parasitaemia, 30-fold in high parasitaemia and 35-fold in fever. There was a poor correlation between CL(int),total and % parasitaemia (r = -0.6). However, log CL(int),total correlated inversely with % parasitaemia (r = -0.9), suggesting that Cl(int),total decreased exponentially with an increase in % parasitaemia. Phenacetin O-deethylation is a marker for cytochrome P4501A2 activity and the results of the present study suggest that both malaria infection and fever might specifically reduce P4501A2 activity in the rat.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Febre/enzimologia , Malária/enzimologia , Microssomos Hepáticos/enzimologia , Oxirredutases/metabolismo , Plasmodium berghei , Acetaminofen/análise , Animais , Citocromo P-450 CYP1A2 , Modelos Animais de Doenças , Endotoxinas , Febre/etiologia , Cinética , Lipopolissacarídeos , Masculino , Preparações Farmacêuticas/metabolismo , Fenacetina/farmacocinética , Ratos , Ratos Wistar
16.
Biochem Pharmacol ; 45(6): 1243-9, 1993 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-8466545

RESUMO

Antipyrine and metronidazole were administered as a cocktail to young (4 weeks old) male Wistar rats (N = 12 for each treatment) to investigate the effect of malaria infection due to the rodent parasite Plasmodium berghei and Escherichia coli endotoxin-induced fever on the metabolism of the two compounds in vivo. Control rats received normal saline. Antipyrine and metronidazole clearances were estimated from a single saliva sample while the formation clearances of their metabolites (in malaria-infected and control rats) were estimated from the product of clearance of parent drug and the fraction of the administered dose excreted as metabolites in urine in 24 hr. Rats treated with endotoxin produced no urine during this period. Malaria infection had no effect on clearance of antipyrine or on formation clearance of any of its metabolites. However, the clearance of metronidazole was reduced by approximately 20% compared with controls as a result of decreased formation of hydroxymetronidazole. Fever decreased clearance of both antipyrine and metronidazole by approximately 36% and 23%, respectively. These results demonstrate that both malaria infection and fever can influence P450-dependent drug metabolism and the effects seen appear to be isozyme-selective.


Assuntos
Antipirina/metabolismo , Febre/metabolismo , Malária/metabolismo , Metronidazol/metabolismo , Plasmodium berghei , Animais , Antipirina/farmacocinética , Temperatura Corporal , Modelos Animais de Doenças , Endotoxinas , Febre/etiologia , Lipopolissacarídeos , Masculino , Taxa de Depuração Metabólica , Metronidazol/farmacocinética , Preparações Farmacêuticas/metabolismo , Ratos , Ratos Wistar , Saliva/química
17.
Biochem Pharmacol ; 47(7): 1137-43, 1994 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-8161342

RESUMO

The influence of p-bromophenacyl bromide (pBPAB) and structural analogues on the assembly and Ca2+ sensitivity of porcine brain microtubules (MTs) was studied by spectrophotometric measurements in vitro. MT assembly was inhibited by 36 microM pBPAB but not by the structural analogues p-chlorophenacyl chloride or acetophenone. In the presence of pBPAB, but not structural analogues, the addition of 10 mM Ca2+ induced aggregation of polymerized MT protein, whereas a decrease in turbidity (due to MT disassembly) was observed in controls. The effects of pBPAB on both MT assembly and Ca2+ sensitivity were blocked by glutathione, but not by N-acetyl L-cysteine, N-acetyl L-lysine nor L-tyrosine, indicating that a highly reduced sulphydryl group(s) may be involved. Western blotting analyses of drug-treated MTs revealed a form of tubulin with altered electrophoretic characteristics, probably caused by a covalent interaction with pBPAB. MT preparations polymerized in the presence of the drug contained fewer MTs than control samples, the predominant structures being identified as amorphous aggregates of MT proteins. The fact that pBPAB affects MT integrity at an effective anti-inflammatory dose in vitro may reflect the involvement of MT disruption in some of the pharmacological effects of this drug. pBPAB is not therefore a suitable tool for studying the specific involvement of phospholipase A2 in cellular events.


Assuntos
Acetofenonas/farmacologia , Encéfalo/efeitos dos fármacos , Microtúbulos/efeitos dos fármacos , Fosfolipases A/antagonistas & inibidores , Animais , Encéfalo/ultraestrutura , Cálcio/farmacologia , Proteínas Associadas aos Microtúbulos/análise , Proteínas Associadas aos Microtúbulos/química , Microtúbulos/ultraestrutura , Fosfolipases A2 , Suínos , Tubulina (Proteína)/química
18.
Reprod Fertil Dev ; 10(6): 499-503, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10588381

RESUMO

This study examined the seasonal variation in ovarian response to the exogenous hormone pregnant mares serum gonadotrophin (PMSG) in the brushtail possum (Trichosurus vulpecula). Ovarian stimulation was achieved by administration of a single intramuscular injection of 15 IU PMSG. Animals (n = 165) responded to this treatment in a variable manner depending on the month of the year. The maximum response (measured by the total number of large (>2 mm) follicles) was 15.8 +/- 1.5 follicles per animal (n = 12) in May and the minimum response was 4.9 +/- 1.6 follicles per animal (n = 7) in January. The response throughout the rest of the year closely paralleled the birth seasonal distribution observed in wild possums in published reports. In the summer months (December, January and February) when few females carried pouch young, 55%, 42% and 17% of PMSG-primed animals, respectively, exhibited a nil response to PMSG (i.e. no follicles >2 mm were found on the ovaries of treated animals). In addition, when wild possums were in lactational anoestrus after the autumnal breeding peak, possums with a nil response to PMSG accounted for 17% (July) and 6% (August) of those treated, but the other animals gave near maximal numbers of large follicles (July, 5-21; August, 2-25). Whether the ovaries of non-responders are downregulated in some manner outside the breeding season or they become insensitive to gonadotrophin remains to be investigated. These observations pinpoint times of the year when the highest productivity can be expected following PMSG treatment, and together with information on the timing of ovulation provide critical data for the development of artificial breeding strategies for the possum.


Assuntos
Gonadotropinas Equinas/farmacologia , Gambás/fisiologia , Ovário/efeitos dos fármacos , Ovário/fisiologia , Estações do Ano , Animais , Cruzamento , Feminino , Gonadotropinas Equinas/administração & dosagem , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Indução da Ovulação/veterinária , Gravidez , Técnicas Reprodutivas/veterinária
19.
Reprod Fertil Dev ; 14(7-8): 453-60, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12617789

RESUMO

Monovulatory brushtail possums (Trichosurus vulpecula) were stimulated with exogenous hormones during seasonal anoestrus to overcome ovarian insensitivity and induce ovulation. Seasonal ovarian insensitivity to pregnant mare serum gonadotrophin (PMSG) was overcome by a new porcine follicle-stimulating hormone/porcine luteinizing hormone (pFSH/pLH) protocol. This protocol was refined because the original treatment produced oocytes with abnormal morphology. Possums (n = 12 per group) received eight injections of pFSH of 1.5, 3.0 or 6.0 mg per injection (at 12-h intervals for 4 consecutive days). Ovulation was induced 12 h after the final pFSH injection with a 4-mg injection of pLH. Control animals were treated with the established protocol of a single injection of 15 IU of PMSG, followed 48 h later with an injection of 4 mg of pLH. All females responded to pFSH/pLH treatment, although optimal stimulation occurred in those receiving 8 x 3 mg pFSH, with 13-14 ovulations and recovery of 11-12 oocytes per female (8 x 1.5 mg pFSH: 13 ovulations, 8-9 oocytes; 8 x 6 mg pFSH: 7-8 ovulations, 4-5 oocytes). In contrast, only seven of 12 females responded to PMSG/pLH and, of those responding, only 2-3 ovulations occurred and only 1-2 oocytes per female were recovered. However, around 80% of oocytes recovered after PMSG/pLH treatment had undergone nuclear maturation (metaphase II/1st polar body) compared with around 60% of oocytes from pFSH/pLH-treated animals. In possums killed from 27 to 39 h after pLH treatment, ovulation onset was first observed from 30 h and by 31.5 h, all animals had completed ovulation. Laparoscopic artificial insemination (LAI) was performed on pFSH/pLH-treated animals to determine whether the oocytes produced were capable of fertilization. Uterine LAI performed 27.5-28.5 h after pLH treatment yielded 11/26 fertilized oocytes (up to 4-cell stage), whereas vaginal LAI performed 13-14 h after pLH treatment yielded 21/53 fertilized oocytes. A proportion of oocytes generated from the refined pFSH/pLH protocol are thus properly mature and capable of fertilization. Further refinement of the protocol is now needed to improve the yield of fully matured oocytes.


Assuntos
Anestro , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Luteinizante/administração & dosagem , Gambás/fisiologia , Indução da Ovulação/veterinária , Suínos , Animais , Feminino , Gonadotropinas Equinas/administração & dosagem , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Laparoscopia/veterinária , Microscopia Eletrônica , Oócitos/ultraestrutura , Indução da Ovulação/métodos , Estações do Ano , Superovulação , Fatores de Tempo , Coleta de Tecidos e Órgãos/veterinária
20.
Reprod Fertil Dev ; 11(6): 329-36, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10972301

RESUMO

Previous studies have demonstrated that co-culture of brushtail possum epididymal spermatozoa with oviduct epithelial cell monolayers prolongs sperm survival and results in the re-orientation of the sperm head and tail to the T-shape (thumbtack) configuration. Transformation of sperm to thumbtack orientation is believed to be associated with marsupial sperm capacitation. Here we report that incubation in oviduct-conditioned media also significantly prolongs sperm survival and results in the transformation of sperm to the thumbtack orientation. The major objective of the current study was to examine the proteins present in the conditioned media, to determine whether any of these proteins specifically bound to sperm and the relationship between these proteins and sperm survival and thumbtack orientation. Co-culturing brushtail possum sperm with biotin-labeled proteins in conditioned media (CM) from ampulla, isthmus and uterine explants demonstrated strong binding of two proteins of molecular mass 230 and 61 kD and weak binding of nine proteins of molecular mass 200, 180, 120, 140, 55, 52, 48, 34, 30 kD to sperm within 30 min. The binding of the 61-kD protein from the conditioned media appeared specific as increasing concentrations of non-labeled oviduct proteins, but not serum proteins, inhibited the binding of labeled proteins. The binding of oviduct and uterine proteins in the conditioned media significantly prolonged sperm survival and percentage motility and also transformed a large number of sperm to a thumbtack orientation. The implication of binding of these proteins is discussed in the context of sperm survival and capacitation in this species.


Assuntos
Gambás/fisiologia , Ovário/metabolismo , Proteínas/metabolismo , Espermatozoides/citologia , Espermatozoides/fisiologia , Animais , Biotina/metabolismo , Sobrevivência Celular , Células Cultivadas , Meios de Cultivo Condicionados , Feminino , Masculino , Ovário/citologia , Motilidade dos Espermatozoides
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