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1.
Qual Health Res ; 32(7): 1086-1098, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35523233

RESUMO

Physical activity (PA) has shown to mitigate many of the common side effects of cancer treatments. The promotion of PA by health care professionals (HCPs) can facilitate the adoption of PA by patients with cancer. Drawing on an empirical ethics of care approach, this article explores how the delivery of PA recommendations is done within clinical cancer care. Based on 175 observations of consultations between doctors, nurses and patients and interviews with 27 doctors and nurses, we show how delivering PA recommendations was related to four care practices: "adjusting information to match the patient's needs and situation," "managing current and anticipated treatment-induced side effects," "using visual aids and quantifiable data," and "maintaining a good relationship between the patient and the HCP." Drawing on these findings, we discuss strategies to strengthen the delivery of PA recommendations in clinical cancer care.


Assuntos
Pacientes Ambulatoriais , Neoplasias da Próstata , Exercício Físico , Pessoal de Saúde , Humanos , Masculino , Neoplasias da Próstata/terapia , Pesquisa Qualitativa
3.
Support Care Cancer ; 27(1): 199-208, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29931489

RESUMO

PURPOSE: Regular exercise is recommended to mitigate the adverse effects of androgen deprivation therapy in men with prostate cancer. The purpose of this study was to explore the experience of transition to unsupervised, community-based exercise among men who had participated in a hospital-based supervised exercise programme in order to propose components that supported transition to unsupervised exercise. METHODS: Participants were selected by means of purposive, criteria-based sampling. Men undergoing androgen deprivation therapy who had completed a 12-week hospital-based, supervised, group exercise intervention were invited to participate. The programme involved aerobic and resistance training using machines and included a structured transition to a community-based fitness centre. Data were collected by means of semi-structured focus group interviews and analysed using thematic analysis. RESULTS: Five focus group interviews were conducted with a total of 29 men, of whom 25 reported to have continued to exercise at community-based facilities. Three thematic categories emerged: Development and practice of new skills; Establishing social relationships; and Familiarising with bodily well-being. These were combined into an overarching theme: From learning to doing. Components suggested to support transition were as follows: a structured transition involving supervised exercise sessions at a community-based facility; strategies to facilitate peer support; transferable tools including an individual exercise chart; and access to 'check-ups' by qualified exercise specialists. CONCLUSIONS: Hospital-based, supervised exercise provides a safe learning environment. Transferring to community-based exercise can be experienced as a confrontation with the real world and can be eased through securing a structured transition, having transferable tools, sustained peer support and monitoring.


Assuntos
Terapia por Exercício/organização & administração , Relações Hospital-Paciente , Cooperação do Paciente/estatística & dados numéricos , Transferência de Pacientes , Neoplasias da Próstata/terapia , Autocuidado , Idoso , Antagonistas de Androgênios/uso terapêutico , Atitude Frente a Saúde , Terapia Combinada , Dinamarca/epidemiologia , Terapia por Exercício/métodos , Terapia por Exercício/psicologia , Grupos Focais , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente/psicologia , Transferência de Pacientes/métodos , Transferência de Pacientes/organização & administração , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/psicologia , Qualidade de Vida , Treinamento Resistido , Autocuidado/métodos , Autocuidado/psicologia
5.
Anim Reprod Sci ; 178: 40-49, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28126267

RESUMO

Porcine somatic cell nuclear transfer (SCNT) has been used extensively to create genetically modified pigs, but the efficiency of the methodology is still low. It has been hypothesized that pluripotent or multipotent stem cells might result in increased SCNT efficacy as these cells are closer than somatic cells to the epigenetic state found in the blastomeres and therefore need less reprogramming. Our group has worked with porcine SCNT during the last 20 years and here we describe our experience with SCNT of 3 different stem cell lines. The porcine stem cells used were: Induced pluripotent stem cells (iPSCs) created by lentiviral doxycycline-dependent reprogramming and cultered with a GSK3ß- and MEK-inhibitor (2i) and leukemia inhibitor factor (LIF) (2i LIF DOX-iPSCs), iPSCs created by a plasmid-based reprogramming and cultured with 2i and fibroblast growth factor (FGF) (2i FGF Pl-iPSCs) and embryonic germ cells (EGCs), which have earlier been characterized as being multipotent. The SCNT efficiencies of these stem cell lines were compared with that of the two fibroblast cell lines from which the iPSC lines were derived. The blastocyst rates for the 2i LIF DOX-iPSCs were 14.7%, for the 2i FGF Pl-iPSC 10.1%, and for the EGCs 34.5% compared with the fibroblast lines yielding 36.7% and 25.2%. The fibroblast- and EGC-derived embryos were used for embryo transfer and produced live offspring at similar low rates of efficiency (3.2 and 4.0%, respectively) and with several instances of malformations. In conclusion, potentially pluripotent porcine stem cells resulted in lower rates of embryonic development upon SCNT than multipotent stem cells and differentiated somatic cells.


Assuntos
Clonagem de Organismos/veterinária , Técnicas de Transferência Nuclear/veterinária , Células-Tronco Pluripotentes/fisiologia , Suínos/genética , Suínos/fisiologia , Animais , Animais Geneticamente Modificados , Linhagem Celular , Reprogramação Celular , Clonagem de Organismos/métodos , Transferência Embrionária/veterinária , Embrião de Mamíferos/fisiologia , Desenvolvimento Embrionário , Feminino , Fibroblastos/fisiologia , Proteínas de Fluorescência Verde , Masculino , Gravidez
6.
Mol Reprod Dev ; 84(3): 229-245, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28044390

RESUMO

Derivation and stable maintenance of porcine induced pluripotent stem cells (piPSCs) is challenging. We herein systematically analyzed two piPSC lines, derived by lentiviral transduction and cultured under either leukemia inhibitory factor (LIF) or fibroblast growth factor (FGF) conditions, to shed more light on the underlying biological mechanisms of porcine pluripotency. LIF-derived piPSCs were more successful than their FGF-derived counterparts in the generation of in vitro chimeras and in teratoma formation. When LIF piPSCs chimeras were transferred into surrogate sows and allowed to develop, only their prescence within the embryonic membranes could be detected. Whole-transcriptome analysis of the piPSCs and porcine neonatal fibroblasts showed that they clustered together, but apart from the two pluripotent cell populations of early porcine embryos, indicating incomplete reprogramming. Indeed, bioinformatic analysis of the pluripotency-related gene network of the LIF- versus FGF-derived piPSCs revealed that ZFP42 (REX1) expression was absent in both piPSC-like cells, whereas it was expressed in the porcine inner cell mass at Day 7/8. A second striking difference was the expression of ATOH1 in piPSC-like cells, which was absent in the inner cell mass. Moreover, our gene expression analyses plus correlation analyses of known pluripotency genes identified unique relationships between pluripotency genes in the inner cell mass, which are to some extent, in the piPSC-like cells. This deficiency in downstream gene activation and divergent gene expression may be underlie the inability to derive germ line-transmitting piPSCs, and provides unique insight into which genes are necessary to achieve fully reprogrammed piPSCs. 84: 229-245, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Crescimento de Fibroblastos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Fator Inibidor de Leucemia/farmacologia , Animais , Células-Tronco Pluripotentes Induzidas/citologia , Suínos
7.
JACC Basic Transl Sci ; 2(5): 591-600, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30062172

RESUMO

Deficiency of apolipoprotein E (APOE) causes familial dysbetalipoproteinemia in humans resulting in a higher risk of atherosclerotic disease. In mice, APOE deficiency results in a severe atherosclerosis phenotype, but it is unknown to what extent this is unique to mice. In this study, APOE was targeted in Yucatan minipigs. APOE-/- minipigs displayed increased plasma cholesterol and accumulation of apolipoprotein B-48-containing chylomicron remnants on low-fat diet, which was significantly accentuated upon feeding a high-fat, high-cholesterol diet. APOE-/- minipigs displayed accelerated progressive atherosclerosis but not xanthoma formation. This indicates that remnant lipoproteinemia does not induce early lesions but is atherogenic in pre-existing atherosclerosis.

8.
JPEN J Parenter Enteral Nutr ; 40(4): 552-66, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-25613990

RESUMO

BACKGROUND: Small enteral boluses with human milk may reduce the risk of subsequent feeding intolerance and necrotizing enterocolitis in preterm infants receiving parenteral nutrition (PN). We hypothesized that feeding amniotic fluid, the natural enteral diet of the mammalian fetus, will have similar effects and improve growth and gastrointestinal (GI) maturation in preterm neonates receiving PN, prior to the transition to milk feeding. MATERIALS AND METHODS: Twenty-seven pigs, delivered by cesarean section at ~90% of gestation, were provided with PN and also fed boluses with amniotic fluid (AF; n = 13, 24-72 mL/kg/d) or no oral supplements (nil per os [NPO]; n = 14) until day 5 when blood, tissue, and fecal samples were collected for analyses. RESULTS: Body weight gain was 2.7-fold higher in AF vs NPO pigs. AF pigs showed slower gastric emptying, reduced meal-induced release of gastric inhibitory peptide and glucagon-like peptide 2, changed gut microbiota, and reduced intestinal permeability. There were no effects on GI weight, percentage mucosa, villus height, plasma citrulline, hexose absorptive capacity, and digestive enzymes. Intestinal interleukin (IL)-1ß levels and expression of IL1B and IL8 were increased in AF pigs, while blood biochemistry and amino acid levels were minimally affected. CONCLUSION: Enteral boluses of AF were well tolerated in the first 5 days of life in preterm pigs receiving PN. Enteral provision of AF before the initiation of milk feeding may stimulate body growth and improve hydration in preterm infants receiving PN. Furthermore, it may improve GI motility and integrity, although most markers of GI maturation remain unchanged.


Assuntos
Líquido Amniótico , Animais Recém-Nascidos/crescimento & desenvolvimento , Trato Gastrointestinal/fisiologia , Nutrição Parenteral/veterinária , Nascimento Prematuro/veterinária , Sus scrofa , Animais , Cesárea/veterinária , Enterocolite Necrosante , Feminino , Polipeptídeo Inibidor Gástrico/metabolismo , Motilidade Gastrointestinal , Trato Gastrointestinal/crescimento & desenvolvimento , Trato Gastrointestinal/microbiologia , Idade Gestacional , Peptídeo 2 Semelhante ao Glucagon/metabolismo , Imunidade , Gravidez , Aumento de Peso
9.
Eur J Oncol Nurs ; 19(4): 419-26, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25631846

RESUMO

PURPOSE: This study explores how patients' experience of sexuality is influenced by physical, psychological and social changes one year after undergoing haematopoietic stem cell transplantation (HSCT). METHODS: A qualitative study using semi-structured in-depth interviews. The respondents (n = 9) were recruited from the Department of Haematology, Copenhagen University Hospital, one year after HSCT. The interviews were analysed from a phenomenological-hermeneutic perspective. RESULTS: Bodily changes and symptoms related to chronic graft vs. host disease led to physical limitations or altered body image, which directly or indirectly resulted in sexual dysfunction or problems with intimacy. Symptoms related to chronic GVHD, could explain experiences of sexual dysfunction. Sexual needs were deprioritized as survival became paramount. The experience of changed social roles, both in family life and social network, affected self-image and identity. Finally, communication about sexuality and sexual needs was of significant importance to the current state of their relationship. CONCLUSION: Physical body alterations, challenges in mastering their new life situation and identity changes affected sexuality and sexual function one year after HSCT. As symptoms resided, sexuality and sex life became more and more prominent in their thoughts and lives. Increased focus is needed on sexuality and sexual dysfunction in the HSCT clinical setting.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Sexualidade , Adulto , Imagem Corporal/psicologia , Comunicação , Dinamarca , Feminino , Doença Enxerto-Hospedeiro/psicologia , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Sexualidade/psicologia , Transplante Homólogo
10.
BMC Vet Res ; 10: 227, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25253618

RESUMO

BACKGROUND: Perosomus elumbis (PE) is a congenital defect that has been observed sporadically in Holstein cattle for many years. However, several cases have been reported in recent years and this may indicate an unrecognised spread of a mutant allele in the Holstein population worldwide. Two cases in Danish Holstein calves are reported to provide details on the phenotype. CASE PRESENTATION: Two full-term Holstein calves were born after assisted delivery due to dystocia with breech presentation. External morphological examination indicated that the lumbar, sacral and coccygeal vertebrae were absent and the abdominal region was just present as a floppy sac covered by skin and enclosing the abdominal organs. The hind limbs were hypoplastic with bilateral symmetric arthrogryposis and muscular atrophy. Radiographs, computed tomography scan and necropsy confirmed these findings. The caudal part of the thoracic spinal cord showed myelodysplasia. A range of abdominal organ malformations were found at necropsy. Inbreeding was not found during genealogical examination, but remote shared ancestors were present in the pedigrees. CONCLUSION: The addition of these further cases of PE to the in recent years reported record of cases should draw more attention to this defect in the Holstein breed. PE may be an emerging genetic defect in the Holstein population worldwide and cases should be sampled to enable genetic mapping of the gene possibly underlying the disease. PE cases seem to be associated with a high risk of dystocia due to increased rate of breech presentation.


Assuntos
Doenças dos Bovinos/congênito , Medula Espinal/anormalidades , Coluna Vertebral/anormalidades , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Dinamarca/epidemiologia
11.
JPEN J Parenter Enteral Nutr ; 38(5): 576-86, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23715776

RESUMO

BACKGROUND: Necrotizing enterocolitis (NEC) is a severe inflammatory disorder, associated with the difficult transition from parenteral to enteral feeding after preterm birth. We hypothesized that minimal enteral nutrition (MEN) with amniotic fluid (AF), prior to enteral formula feeding, would improve resistance to NEC in preterm pigs. METHODS: Experiment 1: IEC-6 cells were incubated with porcine (pAF) and human AF (hAF) to test AF-stimulated enterocyte proliferation and migration in vitro. Experiment 2: Cesarean-delivered, preterm pigs were fed parenteral nutrition and MEN with pAF, hAF, or control fluid (MEN-pAF, MEN-hAF, or MEN-CTRL; all n = 9) for 2 days before tissue collection. Experiment 3: Preterm pigs were fed MEN diets as in experiment 2, but followed by 2 days of enteral formula feeding, which predisposes to NEC (NEC-pAF, NEC-hAF, or NEC-CTRL; n = 10-12). RESULTS: Both pAF and hAF stimulated enterocyte proliferation and migration in vitro. In experiment 2, MEN-pAF and MEN-hAF pigs showed increased body weight gain and reduced intestinal interleukin (IL)-8 and colonic IL-6 levels, indicating reduced inflammatory response. In experiment 3, body weight gain was highest in the 2 groups fed AF as MEN, but NEC incidences were similar (NEC-pAF) or increased (NEC-hAF) compared with controls. CONCLUSIONS: Intake of pAF or hAF improved body growth and modulated intestinal inflammatory cytokines during a period of parenteral nutrition, but did not protect against later formula-induced NEC in preterm pigs. Further studies are required to show if MEN feeding with species-specific AF, combined with an optimal enteral diet (eg, human milk), will improve adaptation during the transition from parenteral to enteral feeding in preterm neonates.


Assuntos
Líquido Amniótico , Animais Recém-Nascidos , Nutrição Enteral/métodos , Enterocolite Necrosante/dietoterapia , Enterocolite Necrosante/prevenção & controle , Nascimento Prematuro , Animais , Peso Corporal/efeitos dos fármacos , Linhagem Celular , Movimento Celular , Proliferação de Células , Enterocolite Necrosante/imunologia , Enterocolite Necrosante/patologia , Enterócitos/citologia , Feminino , Humanos , Inflamação/dietoterapia , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Masculino , Gravidez , Suínos , Resultado do Tratamento
12.
Am J Physiol Regul Integr Comp Physiol ; 305(1): R4-R12, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23657639

RESUMO

Preterm birth and formula feeding predispose to necrotizing enterocolitis (NEC) in infants. As mother's milk is often absent following preterm delivery, infant formula (IF) and human donor milk (HM) are frequently used as alternatives. We have previously shown that porcine and bovine colostrum (BC) provide similar NEC protection in preterm piglets relative to IF. We hypothesized that HM exerts similar effects and that this effect is partly species-independent. Preterm piglets (n = 40) received 2 days of total parenteral nutrition, followed by a rapid transition to full enteral feeding (15 ml·kg(-1)·2 h(-1)) for 2 days using BC (n = 13), HM (n = 13), or IF (n = 14). Intestinal passage time and hexose absorption were tested in vivo. Body and organ weights were recorded on day 5, and macroscopic NEC lesions in the gastrointestinal tract were assessed. Intestinal samples were collected for determination of histomorphology, histopathology, tissue IL-6 and IL-8, organic acids, bacterial adherence by fluorescence in situ hybridization score, and digestive enzyme activities. Relative to IF, pigs from BC and HM showed longer intestinal passage time; higher weight gain, hexose absorptive capacity, mucosal proportion, and enzyme activities; lower NEC incidence, organic acid concentration, and IL-8 concentration; and reduced histopathology lesions. Tissue IL-6 concentration and bacterial adherence score were lower for HM, relative to both BC and IF groups. We conclude that BC and HM are both superior to IF in stimulating gut structure, function, and NEC resistance in preterm piglets. BC may be a relevant alternative to HM when mother's milk is unavailable during the first week after preterm birth.


Assuntos
Colostro/fisiologia , Enterocolite Necrosante/veterinária , Bancos de Leite Humano , Leite Humano/fisiologia , Prenhez/fisiologia , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/prevenção & controle , Animais , Animais Recém-Nascidos , Bovinos , Modelos Animais de Doenças , Nutrição Enteral , Enterocolite Necrosante/epidemiologia , Enterocolite Necrosante/prevenção & controle , Feminino , Humanos , Incidência , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/patologia , Nutrição Parenteral Total , Gravidez , Nascimento Prematuro , Suínos , Doenças dos Suínos/patologia
13.
Sci Transl Med ; 5(166): 166ra1, 2013 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-23283366

RESUMO

Lack of animal models with human-like size and pathology hampers translational research in atherosclerosis. Mouse models are missing central features of human atherosclerosis and are too small for intravascular procedures and imaging. Modeling the disease in minipigs may overcome these limitations, but it has proven difficult to induce rapid atherosclerosis in normal pigs by high-fat feeding alone, and genetically modified models similar to those created in mice are not available. D374Y gain-of-function mutations in the proprotein convertase subtilisin/kexin type 9 (PCSK9) gene cause severe autosomal dominant hypercholesterolemia and accelerates atherosclerosis in humans. Using Sleeping Beauty DNA transposition and cloning by somatic cell nuclear transfer, we created Yucatan minipigs with liver-specific expression of human D374Y-PCSK9. D374Y-PCSK9 transgenic pigs displayed reduced hepatic low-density lipoprotein (LDL) receptor levels, impaired LDL clearance, severe hypercholesterolemia, and spontaneous development of progressive atherosclerotic lesions that could be visualized by noninvasive imaging. This model should prove useful for several types of translational research in atherosclerosis.


Assuntos
Aterosclerose/genética , DNA/genética , Hiperlipoproteinemia Tipo II/genética , Mutação , Pró-Proteína Convertases/genética , Serina Endopeptidases/genética , Animais , Animais Geneticamente Modificados , Clonagem de Organismos , DNA/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Hipercolesterolemia/metabolismo , Fígado/metabolismo , Masculino , Fenótipo , Pró-Proteína Convertase 9 , RNA Mensageiro/metabolismo , Receptores de LDL/metabolismo , Suínos , Porco Miniatura , Transgenes
14.
Reprod Fertil Dev ; 22(4): 625-33, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20353722

RESUMO

The aim of the present study was to characterise bovine epiblast-derived outgrowth colonies (OCs) with respect to the embryonic origin of their cellular components. Epiblasts were isolated mechanically from bovine Day 12 embryos. Epiblasts were cultured on feeder layers of SNL cells (neomycin-resistant leukaemia inhibitory factor (LIF)-producing STO cells) in Dulbecco's modified Eagle's medium (DMEM)/F12 medium supplemented with 15% fetal calf serum, 5% KnockOut Serum Replacement, LIF, basic fibroblast growth factor, non-essential amino acids (NEAA) and nucleosides. Samples were fixed on Days 4, 6 and 8 of culture and processed for immunocytochemistry and transmission electron microscopy. Epiblasts formed OCs consisting of a central core of epiblast-like cells with a basal plate of flattened cells extending outwards from the core. The cells of the core showed nuclear octamer-binding transcription factor 4 (OCT4) staining, indicating an epiblast origin, and some also stained positive for cytoplasmic vimentin. Adjacent cells were linked by tight junctions towards the surface of the colony and rested on a basal lamina. The cells of the basal plate predominantly stained for alpha1-fetoprotein (AFP), indicative of a possible hypoblast origin. Only a few cells scattered within the basal plate exhibited cytokeratin 8 staining, indicating a trophectoderm nature. The intensity of OCT4 and vimentin staining within the core had decreased by Day 8 of culture. In conclusion, OCs derived from bovine Day 12 epiblasts display a central core of OCT4-stained cells of a potential epiblast origin surrounded by a basal plate of mainly AFP-stained cells of a potential hypoblast nature.


Assuntos
Bovinos/fisiologia , Embrião de Mamíferos/fisiologia , Camadas Germinativas/fisiologia , Animais , Bovinos/embriologia , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário/fisiologia , Feminino , Camadas Germinativas/ultraestrutura , Imuno-Histoquímica/veterinária , Microscopia Eletrônica de Transmissão/veterinária , Fator 3 de Transcrição de Octâmero/fisiologia , alfa-Fetoproteínas/fisiologia
15.
Cloning Stem Cells ; 10(3): 325-30, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18479211

RESUMO

An innovative technique, called the high hydrostatic pressure (HHP) treatment, has been recently reported to improve the cryosurvival of gametes or embryos in certain mammalian species. The aim of the present study was to investigate the in vitro and in vivo developmental competence and cryotolerance of embryos produced by handmade cloning (HMC) after pressure treatment of recipient oocytes. In vitro-matured porcine oocytes were treated with a sublethal hydrostatic pressure of 20 MPa (200 times greater than atmospheric pressure) and recovered for either 1 or 2 h (HHP1 and HHP2 groups, respectively) before they were used for HMC. After 7 days of in vitro culture, blastocyst rates and mean cell numbers were determined. Randomly selected blastocysts were vitrified with the Cryotop method based on minimum volume cooling procedure. The blastocyst rate was higher in the HHP2 group than in the control group (68.2 +/- 4.1% vs. 46.4 +/- 4.2%; p < 0.01), while there was no difference between HHP1 and control group (52.1 +/- 1.2% vs. 49.0 +/- 2.7%; p > 0.05). Similar mean cell numbers of produced blastocysts were obtained in HHP2 and control groups (56 +/- 4 vs. 49 +/- 5; p > 0.05). Subsequent blastocyst vitrification with the Cryotop method resulted in significantly higher survival rate after thawing in the HHP2 group than in the control group (61.6 +/- 4.0% vs. 30.2 +/- 30.9%; p < 0.01). Fifty-six and 57 day 5 to day 7 fresh blastocysts in HHP1 group were transferred into two recipient sows on day 5 of the estrous cycle. One recipient was diagnosed pregnant and gave birth to two healthy piglets by naturally delivery on day 122 of gestation. This pilot study proved that the sublethal HHP treatment of porcine oocytes before HMC results in improved in vitro developmental competence and cryotolerance, and supports embryonic and fetal development as well as pregnancy establishment and maintenance up to the birth of healthy piglets.


Assuntos
Sobrevivência Celular , Clonagem de Organismos/métodos , Criopreservação , Pressão Hidrostática , Sus scrofa , Animais , Blastocisto/citologia , Blastocisto/fisiologia , Criopreservação/métodos , Criopreservação/veterinária , Técnicas de Cultura Embrionária/métodos , Técnicas de Cultura Embrionária/veterinária , Feminino , Humanos , Técnicas de Transferência Nuclear , Oócitos , Gravidez , Distribuição Aleatória , Sus scrofa/embriologia
16.
Cloning Stem Cells ; 9(4): 469-76, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18154508

RESUMO

Successful cryopreservation of porcine embryos offers a promising perspective in the fields of agriculture, animal science, and human medical research. The objective of the present work was to establish a system facilitating the cryopreservation of porcine embryos produced by somatic cell nuclear transfer (SCNT). Several key techniques including micromanipulator-based enucleation, noninvasive delipation, zona-free fusion, and activation were combined with high efficiency. After a partial zona digestion and high-speed centrifugation, 89.8+/-2.1% (mean+/-SEM) of enucleated oocytes were successfully delipated. Delipated cytoplasts were incubated for an additional 0.5 or 2 h before fusion with somatic cells. After activation and 6 days of in vitro culture, no significant difference in the rate of blastocysts per reconstructed embryo was observed between the two groups (33.1+/-1.8% and 26.0+/-4.3% for 0.5 and 2 h recovery time, respectively). Cryopreservation of the blastocysts was performed with a Cryotop device and factory-prepared vitrification and warming solutions. One hundred fifty-five vitrified SCNT embryos were transferred surgically into two recipient sows to test their developmental capacity in vivo. One recipient became pregnant and delivered six piglets. In conclusion, our simplified delipation and SCNT procedure resulted in viable piglets after vitrification and embryo transfer at the blastocyst stage.


Assuntos
Blastocisto/citologia , Clonagem de Organismos/métodos , Técnicas de Transferência Nuclear , Animais , Células Cultivadas , Criopreservação/instrumentação , Criopreservação/métodos , Transferência Embrionária/métodos , Feminino , Oócitos/citologia , Gravidez , Prenhez , Suínos , Zona Pelúcida/metabolismo
17.
Gastroenterology ; 130(6): 1776-92, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16697741

RESUMO

BACKGROUND & AIMS: Preterm birth and formula feeding are key risk factors associated with necrotizing enterocolitis (NEC) in infants, but little is known about intestinal conditions that predispose to disease. Thus, structural, functional, and microbiologic indices were used to investigate the etiology of spontaneous NEC development in preterm pigs. METHODS: Piglets were delivered by cesarean section at 92% gestation, reared in infant incubators, and fed infant formula or colostrum every 3 hours (n = 120) until tissue collection at 1-2 days of age. RESULTS: Clinical and histopathologic signs of NEC were observed in 57% of pigs fed FORMULA (26/46) and in 5% of pigs fed COLOSTRUM (2/38) (P < .05). Relative to COLOSTRUM, both healthy and sick FORMULA pigs had reduced intestinal villous heights, enzyme activities, nutrient absorption, and antioxidant levels and higher inducible nitric oxide synthetase activity (P < .05). In healthy pigs, mucosal microbial diversity remained low and diet independent. NEC pigs showed bacterial overgrowth, and a high mucosal density of Clostridium perfringens was detected in some but not all pigs. Germ-free conditions and antiserum against Clostridium perfringens toxin prevented intestinal dysfunction and NEC in formula-fed pigs, whereas the gut trophic factors, epidermal growth factor, and glucagon-like peptide 2 had limited effects. CONCLUSIONS: A subclinical, formula-induced mucosal atrophy and dysfunction predispose to NEC and bacterial overgrowth. The adverse feeding effects are colonization dependent and may be reduced by factors in colostrum that include antibodies against aggressive toxins such as those of Clostridium perfringens.


Assuntos
Enterocolite Necrosante/epidemiologia , Enterocolite Necrosante/prevenção & controle , Fórmulas Infantis/administração & dosagem , Intestino Delgado/metabolismo , Prenhez , Animais , Animais Recém-Nascidos , Sequência de Bases , Biópsia por Agulha , Causalidade , Contagem de Colônia Microbiana , Colostro , DNA Bacteriano/análise , Enterocolite Necrosante/patologia , Feminino , Trato Gastrointestinal/microbiologia , Imuno-Histoquímica , Absorção Intestinal/fisiologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Intestino Delgado/embriologia , Intestino Delgado/patologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/métodos , Gravidez , Nascimento Prematuro , Probabilidade , Fatores de Risco , Sensibilidade e Especificidade , Suínos
18.
Am J Physiol Regul Integr Comp Physiol ; 289(4): R1212-22, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15961526

RESUMO

Preterm birth and formula feeding predispose to small intestinal dysfunction, which may lead to necrotizing enterocolitis (NEC). In piglets, we tested whether the physiological and environmental transitions occurring at birth affect the response of the immature intestine to enteral feeding. Pig fetuses (106 days gestation, term = 115 days) were prepared with esophageal feeding tubes and fed either sow's colostrum (n = 8) or infant formula (n = 7) in utero. After 24 h of oral feeding, the pig fetuses were delivered by cesarean section and their gastrointestinal morphology and function were compared with those of preterm newborn (NB) littermates that were not fed (n = 8) or fed colostrum (n = 7) or formula (n = 13) for 24 h after birth. Before birth, both colostrum and formula feeding resulted in marked increases in intestinal mass, brush-border enzyme activities, and plasma glucagon-like peptide 2 concentrations, to levels similar to those in NB colostrum-fed piglets. In contrast, NB formula-fed piglets showed reduced intestinal growth, decreased brush-border enzyme activities, and intestinal lesions, reflecting NEC. NB formula-fed pigs also showed impaired enterocyte endocytotic function and decreased antioxidative capacity, whereas brush-border enzyme mRNA levels were unaltered, relative to NB colostrum-fed pigs. Our results indicate that the feeding-induced growth and enzyme maturation of the immature intestine are not birth dependent. However, with a suboptimal diet (milk formula), factors related to preterm birth (e.g., microbial colonization and metabolic and endocrine changes) make the immature intestine sensitive to atrophy and development of NEC.


Assuntos
Fórmulas Infantis/administração & dosagem , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Peptídeos/metabolismo , Nascimento Prematuro/metabolismo , Nascimento Prematuro/patologia , Vitamina E/metabolismo , Animais , Animais Recém-Nascidos , Atrofia , Peptídeo 2 Semelhante ao Glucagon , Peptídeos Semelhantes ao Glucagon , Intestino Delgado/embriologia , Intestino Delgado/crescimento & desenvolvimento , Tamanho do Órgão/efeitos dos fármacos , Nascimento Prematuro/complicações , Suínos
19.
Pediatr Res ; 52(4): 498-503, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12357042

RESUMO

Exogenous glucagon-like peptide 2 (GLP-2) mimics the stimulatory effect of enteral nutrition on intestinal mucosal growth in preterm neonatal pigs. Little is known about its effects on small intestinal function. In this study, we investigated whether the trophic actions of GLP-2 and enteral nutrition are paralleled by effects on small intestinal function. Cesarean-delivered piglets (92% of gestation) were given either a parenteral nutrient infusion [total parenteral nutrition (TPN), n = 7], TPN + human GLP-2 (25 nmol/kg/d, n = 8), or enteral nutrition (ENT, n = 6) for 6 d. Gene expression (mRNA) and activities of lactase phlorizin hydrolase (LPH), maltase-glucoamylase (MGA), sucrase-isomaltase (SI), aminopeptidase N (ApN), and A (ApA) and dipeptidyl peptidase IV (DPP IV) were measured. Both GLP-2 and enteral nutrition increased mucosal weight (+30-40%, p < 0.05) relative to TPN. GLP-2 stimulated jejunal MGA and SI mRNA abundance and activity levels but did not change LPH in parenterally fed pigs (p < 0.05). Enteral nutrition decreased jejunal LPH and MGA mRNA abundance and activity and increased ileal ApN, ApA, and DPP IV activities relative to TPN (p < 0.05). We conclude that GLP-2 and enteral nutrition exert different effects on intestinal enzyme function despite similar effects on intestinal growth. In addition, the effects of GLP-2 on intestinal function in these parenterally fed, premature neonatal pigs differed from those previously reported for similarly fed term neonates.


Assuntos
Animais Recém-Nascidos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Nutrição Parenteral , Peptídeos/farmacologia , Complexo Sacarase-Isomaltase/genética , alfa-Glucosidases/genética , Animais , Peptídeo 2 Semelhante ao Glucagon , Peptídeos Semelhantes ao Glucagon , Tamanho do Órgão , Peptídeos/sangue , Radioimunoensaio , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos
20.
Mol Reprod Dev ; 62(4): 483-8, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12112581

RESUMO

The frequency of polyploid cells in the embryonic disc (ED) and in the trophectoderm (TE) was assessed in 50 in vitro produced bovine embryos fixed at days 7-8 post insemination (pi) and in 20 in vitro produced embryos that were transferred to uteri of recipients at day 7 and then recovered and fixed at day 12 pi. Separation of TE and ED cells was obtained by microdissection and the frequency of polyploid cells was determined by interphase cytogenetic analysis using fluorescence in situ hybridization (FISH) with chromosome 6- and chromosome 7-specific probes. The results show that 96% of day 7 embryos contain polyploid cells in the TE, whereas only 58% contain polyploid cells in the ED. In day 12 embryos 85% of TE and 40% of ED preparations contain polyploid cells. Statistical analysis revealed that the frequency of polyploid cells was significantly higher in the TE than in the ED in embryos containing less than 25% polyploid cells (n = 65). The few embryos (n = 5), which contained more than 25% polyploid cells, did not show this difference. Further, it was revealed that the level of polyploidy on day 7-8 was significantly higher than on day 12, both in the TE (two-fold) and in the ED (seven-fold).


Assuntos
Blastocisto/citologia , Poliploidia , Animais , Bovinos , Ectoderma/citologia
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