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1.
Qual Health Res ; 32(7): 1086-1098, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35523233

RESUMEN

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.


Asunto(s)
Pacientes Ambulatorios , Neoplasias de la Próstata , Ejercicio Físico , Personal de Salud , Humanos , Masculino , Neoplasias de la Próstata/terapia , Investigación Cualitativa
2.
Support Care Cancer ; 27(1): 199-208, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29931489

RESUMEN

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.


Asunto(s)
Terapia por Ejercicio/organización & administración , Relaciones Paciente-Hospital , Cooperación del Paciente/estadística & datos numéricos , Transferencia de Pacientes , Neoplasias de la Próstata/terapia , Autocuidado , Anciano , Antagonistas de Andrógenos/uso terapéutico , Actitud Frente a la Salud , Terapia Combinada , Dinamarca/epidemiología , Terapia por Ejercicio/métodos , Terapia por Ejercicio/psicología , Grupos Focales , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Cooperación del Paciente/psicología , Transferencia de Pacientes/métodos , Transferencia de Pacientes/organización & administración , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/psicología , Calidad de Vida , Entrenamiento de Fuerza , Autocuidado/métodos , Autocuidado/psicología
3.
Mol Reprod Dev ; 84(3): 229-245, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28044390

RESUMEN

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.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Crecimiento de Fibroblastos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Células Madre Pluripotentes Inducidas/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Factor Inhibidor de Leucemia/farmacología , Animales , Células Madre Pluripotentes Inducidas/citología , Porcinos
4.
J Pediatr Gastroenterol Nutr ; 61(4): 481-90, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25883061

RESUMEN

OBJECTIVES: The primary risk factors for necrotizing enterocolitis (NEC) are preterm birth, enteral feeding, and gut colonization. It is unclear whether feeding and colonization induce excessive expression of immune genes that lead to NEC. Using a pig model, we hypothesized that reduced gestational age would upregulate immune-related genes and cause bacterial imbalance after birth. METHODS: Preterm (85%-92% gestation, n = 53) and near-term (95%-99% gestation, n = 69) pigs were delivered by cesarean section and euthanized at birth or after 2 days of infant formula or bovine colostrum feeding. RESULTS: At birth, preterm delivery reduced 5 of 30 intestinal genes related to nutrient absorption and innate immunity, relative to near-term pigs, whereas 2 genes were upregulated. Preterm birth also reduced ex vivo intestinal glucose and leucine uptake (40%-50%), but failed to increase cytokine secretions from intestinal explants relative to near-term birth. After 2 days of formula feeding, NEC incidence was increased in preterm versus near-term pigs (47% vs 0%-13%). A total of 6 of the 30 genes related to immunity (TLR2, IL1B, and IL8), permeability (CLDN3, and OCLN), and absorption (SGLT) decreased in preterm pigs without affecting Gram-negative bacteria-related responses (TLR4, IKBA, NFkB1, TNFAIP3, and PAFA). Bacterial abundance tended to be higher in preterm versus near-term pigs (P = 0.09), whereas the composition was unaffected. CONCLUSIONS: Preterm birth predisposes to NEC and reduces nutrient absorption but does not induce upregulation of immune-related genes or cause bacterial dyscolonization in the neonatal period. Excessive inflammation and bacterial overgrowth may occur relatively late in NEC progression in preterm neonates.


Asunto(s)
Digestión , Modelos Animales de Enfermedad , Microbioma Gastrointestinal , Regulación del Desarrollo de la Expresión Génica , Absorción Intestinal , Síndromes de Malabsorción/etiología , Nacimiento Prematuro/fisiopatología , Animales , Biomarcadores/metabolismo , Bovinos , Calostro/inmunología , Calostro/metabolismo , Cruzamientos Genéticos , Dinamarca , Disbiosis/etiología , Disbiosis/prevención & control , Enteritis/etiología , Enteritis/prevención & control , Enterocolitis Necrotizante/etiología , Enterocolitis Necrotizante/prevención & control , Microbioma Gastrointestinal/inmunología , Inmunidad Innata , Inmunidad Mucosa , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Mucosa Intestinal/patología , Yeyuno/inmunología , Yeyuno/metabolismo , Yeyuno/microbiología , Yeyuno/patología , Síndromes de Malabsorción/prevención & control , Nacimiento Prematuro/metabolismo , Nacimiento Prematuro/microbiología , Nacimiento Prematuro/patología , Sus scrofa , Técnicas de Cultivo de Tejidos
5.
Reprod Fertil Dev ; 27(3): 429-39, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25482653

RESUMEN

During the last 17 years, considerable advancements have been achieved in the production of pigs, transgenic and non-transgenic, by methods of somatic cell nuclear transfer, in vitro fertilisation, intracytoplasmic sperm injection, microinjection and sperm-mediated gene transfer by artificial insemination. Therefore, a review of the overall efficiency for the developmental competence of embryos produced by these in vitro methods would be useful in order to obtain a more thorough overview of this growing area with respect to its development and present status. In this review a meta-analysis was used to analyse data collected from all published articles with a focus on zygotes and embryos for transfer, pregnancy, full-term development and piglets born. It was generally concluded that an increasing level of in vitro manipulation of porcine embryos decreased the overall efficiency for production of piglets. The techniques of nuclear transfer have been developed markedly through the increasing number of studies performed, and the results have become more stable. Prolonged in vitro culture period did not lead to any negative effect on nuclear transfer embryos after their transfer and it resulted in a similar or even higher litter size. More complete information is needed in future scientific articles about these in vitro manipulation techniques to establish a more solid basis for the evaluation of their status and to reveal and further investigate any eventual problems.


Asunto(s)
Transferencia de Embrión/veterinaria , Desarrollo Embrionario/fisiología , Fertilización In Vitro/veterinaria , Técnicas de Transferencia Nuclear/veterinaria , Animales , Animales Modificados Genéticamente , Transferencia de Embrión/métodos , Femenino , Fertilización In Vitro/métodos , Tamaño de la Camada , Embarazo , Porcinos
6.
Am J Physiol Gastrointest Liver Physiol ; 306(1): G59-71, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24157972

RESUMEN

Preterm birth, bacterial colonization, and formula feeding predispose to necrotizing enterocolitis (NEC). Antibiotics are commonly administered to prevent sepsis in preterm infants, but it is not known whether this affects intestinal immunity and NEC resistance. We hypothesized that broad-spectrum antibiotic treatment improves NEC resistance and intestinal structure, function, and immunity in neonates. Caesarean-delivered preterm pigs were fed 3 days of parenteral nutrition followed by 2 days of enteral formula. Immediately after birth, they were assigned to receive either antibiotics (oral and parenteral doses of gentamycin, ampicillin, and metronidazole, ANTI, n = 11) or saline in the control group (CON, n = 13), given twice daily. NEC lesions and intestinal structure, function, microbiology, and immunity markers were recorded. None of the ANTI but 85% of the CON pigs developed NEC lesions by day 5 (0/11 vs. 11/13, P < 0.05). ANTI pigs had higher intestinal villi (+60%), digestive enzyme activities (+53-73%), and goblet cell densities (+110%) and lower myeloperoxidase (-51%) and colonic microbial density (10(5) vs. 10(10) colony-forming units, all P < 0.05). Microarray transcriptomics showed strong downregulation of genes related to inflammation and innate immune response to microbiota and marked upregulation of genes related to amino acid metabolism, in particular threonine, glucose transport systems, and cell cycle in 5-day-old ANTI pigs. In a follow-up experiment, 5 days of antibiotics prevented NEC at least until day 10. Neonatal prophylactic antibiotics effectively reduced gut bacterial load, prevented NEC, intestinal atrophy, dysfunction, and inflammation and enhanced expression of genes related to gut metabolism and immunity in preterm pigs.


Asunto(s)
Ampicilina/farmacología , Enterocolitis Necrotizante , Gentamicinas/farmacología , Inmunidad Mucosa/efectos de los fármacos , Metronidazol/farmacología , Microbiota/efectos de los fármacos , Aminoácidos/metabolismo , Animales , Animales Recién Nacidos , Antibacterianos/farmacología , Profilaxis Antibiótica/métodos , Modelos Animales de Enfermedad , Enterocolitis Necrotizante/inmunología , Enterocolitis Necrotizante/patología , Enterocolitis Necrotizante/prevención & control , Femenino , Mucosa Intestinal/metabolismo , Intestinos/microbiología , Intestinos/patología , Trabajo de Parto Prematuro/inmunología , Embarazo , Porcinos
7.
BMC Vet Res ; 10: 227, 2014 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-25253618

RESUMEN

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.


Asunto(s)
Enfermedades de los Bovinos/congénito , Médula Espinal/anomalías , Columna Vertebral/anomalías , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Dinamarca/epidemiología
8.
Reprod Fertil Dev ; 26(7): 1017-31, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25145414

RESUMEN

In somatic cell nuclear transfer (SCNT), donor cell reprogramming is considered as a biologically important and vulnerable event. Various donor cell pre-treatments with Xenopus egg extracts can promote reprogramming. Here we investigated if the reprogramming effect of one treatment with Xenopus egg extract on donor cells was maintained for several cell passages. The extract treatment resulted in increased cell-colony formation from early passages in treated porcine fibroblasts (ExTES), and increased development of cloned embryos. Partial dedifferentiation was observed in ExTES cells, shown as a tendency towards upregulation of NANOG, c-MYC and KLF-4 and downregulation of DESMIM compared with ExTES at Passage 2. Compared with our routine SCNT, continuously increased development of cloned embryos was observed in the ExTES group, and ExTES cloned blastocysts displayed hypermethylated DNA patterns and hypermethylation of H3K4me3 and H3K27me3 in ICM compared with TE. All seven recipients became pregnant after transferral of ExTES cloned embryos and gave birth to 7-22 piglets per litter (average 12). In conclusion, our results demonstrate that one treatment of porcine fibroblasts with Xenopus egg extract can result in long-term increased ability of the cells to promote their in vitro function in subsequent SCNT. Finally these cells can also result in successful development of cloned embryos to term.


Asunto(s)
Clonación de Organismos/veterinaria , Técnicas de Transferencia Nuclear/veterinaria , Óvulo/química , Sus scrofa , Xenopus , Animales , Células Cultivadas , Reprogramación Celular/genética , Clonación de Organismos/métodos , Metilación de ADN , Transferencia de Embrión/veterinaria , Desarrollo Embrionario , Femenino , Fibroblastos/ultraestructura , Expresión Génica , Histonas/metabolismo , Masculino , Metilación , Proteínas Nucleares/análisis , Nucleofosmina , Proteínas del Complejo de Iniciación de Transcripción Pol1/análisis , Embarazo
9.
Zygote ; 22(3): 356-65, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23331714

RESUMEN

In this study, the developmental ability of cloned embryos using gilt versus sow oocytes was evaluated under the hypothesis that the efficiency of nuclear transfer using gilt oocytes was lower than that of sow oocytes, but that it could be optimized. Five experiments were performed with routine production of cloned embryos with sow oocytes serving as the control. Results showed that: Experiment 1: Blastocyst rates of cloned embryos with gilt oocytes was about half compared with control. Experiment 2: An extended maturation time of 48 h used for gilt oocytes resulted in lower blastocyst rates after cloning. Experiment 3: Development of cloned embryos with gilt oocytes was improved by co-culture with sow oocytes. Experiment 4: After maturation of gilt oocytes using follicular fluid from gilt instead of sow, the oocytes were sorted into large and small oocytes, and after cloning, blastocyst rates were higher using large gilt oocytes compared with small oocytes; however, the rate remained lower compared with control. Experiment 5: Six sow recipients received a total of 503 morulae and blastocysts cloned from gilt oocytes (four recipients) and 190 cloned from sow oocytes (two recipients). All recipients became pregnant and went to term, resulting in 26 (gilt oocytes) and six (sow oocytes) piglets. In conclusion, results confirmed that nuclear transfer efficiency was higher using sow versus gilt oocytes, but the use of gilt oocytes can be optimized by sorting after ooplasm size following maturation and by maturing gilt and sow oocytes together.


Asunto(s)
Blastocisto/fisiología , Clonación de Organismos/métodos , Técnicas de Maduración In Vitro de los Oocitos , Técnicas de Transferencia Nuclear , Oocitos/citología , Animales , Técnicas de Cocultivo , Citoplasma , Femenino , Embarazo , Pubertad , Porcinos
10.
Am J Physiol Gastrointest Liver Physiol ; 304(10): G864-75, 2013 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-23518680

RESUMEN

Preterm neonates are susceptible to gastrointestinal disorders such as necrotizing enterocolitis (NEC). Maternal milk and colostrum protects against NEC via growth promoting, immunomodulatory, and antimicrobial factors. The fetal enteral diet amniotic fluid (AF), contains similar components, and we hypothesized that postnatal AF administration reduces inflammatory responses and NEC in preterm neonates. Preterm pigs (92% gestation) were delivered by caesarean section and fed parental nutrition (2 days) followed by enteral (2 days) porcine colostrum (COLOS, n = 7), infant formula (FORM, n = 13), or AF supplied before and after introduction of formula (AF, n = 10) in experiment 1, and supplied only during the enteral feeding period in experiment 2 (FORM, n = 16; AF, n = 14). The NEC score was reduced in both AF and COLOS pigs, relative to FORM, when AF was provided prior to full enteral feeding (9.9 and 7.7 compared with 17.3, P < 0.05). There was no effect of AF when provided only during enteral feeding. AF pigs showed decreased bacterial abundance in colon and intestinal inflammation-related genes (e.g., TNF-α, IL-1α, IL-6, NOS) were downregulated, relative to FORM pigs with NEC. Anti-inflammatory properties of AF were supported by delayed maturation and decreased TNF-α production in murine dendritic cells, as well as increased proliferation and migration, and downregulation of IL-6 expression in intestinal cells (IEC-6, IPEC-J2). Like colostrum, AF may reduce NEC development in preterm neonates by suppressing the proinflammatory responses to enteral formula feeding and gut colonization when provided before the onset of NEC.


Asunto(s)
Líquido Amniótico/fisiología , Calostro/fisiología , Enterocolitis Necrotizante/terapia , Gastroenteritis/terapia , Animales , Animales Recién Nacidos , Citocinas/metabolismo , Células Dendríticas/metabolismo , Nutrición Enteral , Enterocolitis Necrotizante/microbiología , Enterocolitis Necrotizante/patología , Enterocitos/metabolismo , Femenino , Gastroenteritis/microbiología , Gastroenteritis/patología , Humanos , Recién Nacido , Recien Nacido Prematuro , Absorción Intestinal , Intestinos/microbiología , Análisis por Micromatrices , Nutrición Parenteral Total , Permeabilidad , Embarazo , ARN/biosíntesis , ARN/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Porcinos
11.
Am J Physiol Regul Integr Comp Physiol ; 305(1): R4-R12, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23657639

RESUMEN

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.


Asunto(s)
Calostro/fisiología , Enterocolitis Necrotizante/veterinaria , Bancos de Leche Humana , Leche Humana/fisiología , Preñez/fisiología , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/prevención & control , Animales , Animales Recién Nacidos , Bovinos , Modelos Animales de Enfermedad , Nutrición Enteral , Enterocolitis Necrotizante/epidemiología , Enterocolitis Necrotizante/prevención & control , Femenino , Humanos , Incidencia , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/patología , Nutrición Parenteral Total , Embarazo , Nacimiento Prematuro , Porcinos , Enfermedades de los Porcinos/patología
12.
Transgenic Res ; 22(4): 709-23, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23111619

RESUMEN

Targeted transgenesis using site-specific recombinases is an attractive method to create genetically modified animals as it allows for integration of the transgene in a pre-selected transcriptionally active genomic site. Here we describe the application of recombinase-mediated cassette exchange (RMCE) in cells from a Göttingen minipig with four RMCE acceptor loci, each containing a green fluorescence protein (GFP) marker gene driven by a human UbiC promoter. The four RMCE acceptor loci segregated independent of each other, and expression profiles could be determined in various tissues. Using minicircles in RMCE in fibroblasts with all four acceptor loci and followed by SCNT, we produced piglets with a single copy of a transgene incorporated into one of the transcriptionally active acceptor loci. The transgene, consisting of a cDNA of the Alzheimer's disease-causing gene PSEN1M146I driven by an enhanced human UbiC promoter, had an expression profile in various tissues similar to that of the GFP marker gene. The results show that RMCE can be done in a pre-selected transcriptionally active acceptor locus for targeted transgenesis in pigs.


Asunto(s)
Técnicas de Transferencia Nuclear , Presenilina-1/genética , Porcinos Enanos/genética , Transgenes , Animales , Animales Modificados Genéticamente , ADN Complementario/genética , Fibroblastos/citología , Fibroblastos/metabolismo , Genoma , Humanos , Recombinasas/genética , Porcinos
13.
Cryobiology ; 64(1): 60-4, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21945817

RESUMEN

The objective of this experiment was to determine the optimal developmental stage to vitrify in vitro cultured porcine parthenogenetically activated (PA) embryos. Embryos were vitrified by Cryotop on Day 4, 5 or 6 after oocyte activation (Day 0), and immediately after warming they were either time-lapse monitored for 24h or analyzed by differential staining. After warming, the embryos had to be cultured for at least 8h before their survival rates were stabilized. Both the survival rate at 8h and the hatching rate at 24h of Day 4 embryos were significant higher than those vitrified on Day 5 or 6 (P<0.05), no matter if they were morulae or blastocysts. These results demonstrate that porcine PA embryos can survive successfully after vitrification/warming, that the optimal time for vitrification was Day 4 for both morulae and blastocysts, and that 8h after warming was the time needed to make an early evaluation of porcine PA embryo survival.


Asunto(s)
Criopreservación/métodos , Embrión de Mamíferos/fisiología , Partenogénesis , Animales , Blastocisto/fisiología , Técnicas de Cultivo de Embriones , Mórula/fisiología , Tasa de Supervivencia , Porcinos/embriología , Vitrificación
14.
J Nutr ; 141(7): 1306-11, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21593357

RESUMEN

Threonine is an essential amino acid necessary for synthesis of intestinal (glyco)proteins such as mucin MUC2 to maintain adequate gut barrier function. In premature infants, reduced barrier function may contribute to the development of necrotizing enterocolitis (NEC). Human milk protects against NEC compared with infant formula. Therefore, we hypothesized that formula feeding decreases the MUC2 synthesis rate concomitant with a decrease in intestinal first-pass threonine utilization, predisposing the preterm neonate to NEC. Preterm pigs were delivered by caesarian section and received enteral feeding with formula (FORM; n = 13) or bovine colostrum (COL; n = 6) for 2 d following 48 h of total parenteral nutrition. Pigs received a dual stable isotope tracer infusion of threonine to determine intestinal threonine kinetics. NEC developed in 38% of the FORM pigs, whereas none of the COL pigs were affected (P = 0.13). Intestinal fractional first-pass threonine utilization was lower in FORM pigs (49 ± 2%) than in COL pigs (60 ± 4%) (P = 0.02). In FORM pigs compared with COL pigs, protein synthesis (369 ± 31 mg·kg(-1)·d(-1) vs. 615 ± 54 mg·kg(-1)·d(-1); P = 0.003) and MUC2 synthesis (121 ± 17%/d vs. 184 ± 15%/d; P = 0.02) were lower in the distal small intestine (SI). Our results suggest that formula feeding compared with colostrum feeding in preterm piglets reduces mucosal growth with a concomitant decrease in first-pass splanchnic threonine utilization, protein synthesis, and MUC2 synthesis in the distal SI. Hence, decreased intestinal threonine metabolism and subsequently impaired gut barrier function may predispose the formula-fed infant to developing NEC.


Asunto(s)
Fórmulas Infantiles/administración & dosificación , Mucosa Intestinal/metabolismo , Mucina 2/biosíntesis , Biosíntesis de Proteínas , Treonina/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Animales Recién Nacidos , Bovinos , Calostro , Enterocolitis Necrotizante/etiología , Enterocolitis Necrotizante/prevención & control , Femenino , Humanos , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Recien Nacido Prematuro , Intestinos/patología , Modelos Animales , Embarazo , Factores de Riesgo , Sus scrofa
15.
Transgenic Res ; 20(3): 533-45, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20803249

RESUMEN

Modelling of human disease in genetically engineered pigs provides unique possibilities in biomedical research and in studies of disease intervention. Establishment of methodologies that allow efficient gene insertion by non-viral gene carriers is an important step towards development of new disease models. In this report, we present transgenic pigs created by Sleeping Beauty DNA transposition in primary porcine fibroblasts in combination with somatic cell nuclear transfer by handmade cloning. Göttingen minipigs expressing green fluorescent protein are produced by transgenesis with DNA transposon vectors carrying the transgene driven by the human ubiquitin C promoter. These animals carry multiple copies (from 8 to 13) of the transgene and show systemic transgene expression. Transgene-expressing pigs carry both transposase-catalyzed insertions and at least one copy of randomly inserted plasmid DNA. Our findings illustrate critical issues related to DNA transposon-directed transgenesis, including coincidental plasmid insertion and relatively low Sleeping Beauty transposition activity in porcine fibroblasts, but also provide a platform for future development of porcine disease models using the Sleeping Beauty gene insertion technology.


Asunto(s)
Animales Modificados Genéticamente , Elementos Transponibles de ADN/genética , Técnicas de Transferencia de Gen , Mutagénesis Insercional , Transposasas/metabolismo , Animales , Secuencia de Bases , Fibroblastos/metabolismo , Ingeniería Genética/métodos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Datos de Secuencia Molecular , Porcinos , Porcinos Enanos , Transgenes/genética , Transgenes/fisiología , Transposasas/genética
16.
Pediatr Res ; 69(2): 123-8, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21045752

RESUMEN

Intestinal adaptation from parenteral to enteral nutrition is crucial for survival and growth of newborns. Rapid feeding-induced gut maturation occurs immediately after birth in both preterm and term neonates, but it remains unclear whether the responses depend on factors related to birth transition (e.g. bacterial colonization, endocrine, and metabolic changes). We hypothesized that enteral feeding matures the immature intestine, even in fetuses before birth. Hence, control pig fetuses were compared with fetuses fed with milk formula for 24 h in utero. Gel-based proteomics showed that feeding-induced changes in 38 proteins, along with marked increases in intestinal mass and changes in activities of brush border enzymes. Physiological functions of the identified proteins were related to enterocyte apoptosis (e.g. caspase 1) and nutrient metabolism (e.g. citric acid cycle proteins). Many of the differentiated proteins were similar to those identified previously in preterm pigs fed with the same formula after birth, except that effects on proteins related to inflammatory lesions (e.g. heat shock proteins) were absent. Our results show that enteral feeding, independently of the birth transition, induces marked gut maturation and proteome change in the immature intestine. Hence, immediate postnatal feeding-induced gut changes are largely independent of factors related to the birth transition.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Nutrición Enteral , Proteínas Fetales/metabolismo , Fórmulas Infantiles/administración & dosificación , Intestino Delgado/metabolismo , Fenómenos Fisiologicos Nutricionales Maternos , Proteómica , Adaptación Fisiológica , Animales , Western Blotting , Electroforesis en Gel Bidimensional , Femenino , Humanos , Recién Nacido , Intestino Delgado/embriología , Intestino Delgado/patología , Embarazo , Proteómica/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Porcinos , Factores de Tiempo
17.
Br J Nutr ; 106(6): 852-61, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21676273

RESUMEN

Uterine infections during pregnancy predispose to pre-term birth and postnatal morbidity, but it is unknown how prenatal bacterial exposure affects maturation of the immature gut. We hypothesised that a prenatal exposure to gram-negative lipopolysaccharide (LPS) has immunomodulatory effects that improve resistance towards necrotising enterocolitis (NEC) in pre-term neonates. At approximately 85 % gestation, pig fetuses were injected intramuscularly with saline or LPS (0·014 mg/kg), or intra-amniotically with LPS (0·4 mg/kg). Pigs were delivered by caesarean section 3-5 d later and fed colostrum (C) or formula (F) for 48 h. Gut indices did not differ between pigs injected intramuscularly with saline or LPS, and these groups were therefore pooled into two control groups according to diet (control-F, n 32 and control-C, n 11). Control-F pigs showed reduced villus heights, mucosal structure, gut integrity, digestive enzymes, elevated NEC incidence (38 v. 0 %, P < 0·05) and several differentially expressed immune-related genes, relative to control-C pigs. Compared with the control-F and control-C groups, values in formula-fed pigs given intra-amniotic LPS formula (n 17) were intermediate for villus height, enzyme activities, intestinal permeability and NEC incidence (18 %, P = 0·2 relative to control-F), and numbers of differentially expressed immune genes. In conclusion, prenatal exposure of the fetal gut to Gram-negative bacteria may modulate the immediate postnatal response to an enteral diet and colonising bacteria.


Asunto(s)
Enterocolitis Necrotizante/prevención & control , Lipopolisacáridos/metabolismo , Alimentación Animal , Animales , Dieta , Enterocolitis Necrotizante/embriología , Escherichia coli/metabolismo , Femenino , Mucosa Intestinal/metabolismo , Intestinos/embriología , Exposición Materna , Permeabilidad , Embarazo , Preñez , Porcinos , Factores de Tiempo
18.
BMC Physiol ; 11: 14, 2011 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-21859467

RESUMEN

BACKGROUND: Pigs are widely used as models for human physiological changes in intervention studies, because of the close resemblance between human and porcine physiology and the high degree of experimental control when using an animal model. Cloned animals have, in principle, identical genotypes and possibly also phenotypes and this offer an extra level of experimental control which could possibly make them a desirable tool for intervention studies. Therefore, in the present study, we address how phenotype and phenotypic variation is affected by cloning, through comparison of cloned pigs and normal outbred pigs. RESULTS: The metabolic phenotype of cloned pigs (n = 5) was for the first time elucidated by nuclear magnetic resonance (NMR)-based metabolomic analysis of multiple bio-fluids including plasma, bile and urine. The metabolic phenotype of the cloned pigs was compared with normal outbred pigs (n = 6) by multivariate data analysis, which revealed differences in the metabolic phenotypes. Plasma lactate was higher for cloned vs control pigs, while multiple metabolites were altered in the bile. However a lower inter-individual variability for cloned pigs compared with control pigs could not be established. CONCLUSIONS: From the present study we conclude that cloned and normal outbred pigs are phenotypically different. However, it cannot be concluded that the use of cloned animals will reduce the inter-individual variation in intervention studies, though this is based on a limited number of animals.


Asunto(s)
Clonación de Organismos , Metabolómica , Porcinos/genética , Porcinos/metabolismo , Animales , Bilis/química , Femenino , Ácido Láctico/sangre , Fenotipo , Plasma/química , Orina/química
19.
Urology ; 147: 68-73, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32916191

RESUMEN

OBJECTIVE: To investigate the prevalence of burnout among Danish and American urologists. METHODS: An email invitation was sent with 2 reminders spaced by 14 days intervals to members of the Danish Urological Association and urologists at the University of Michigan to participate in a survey consisting of the 2 item Maslach Burnout Inventory. Burnout was defined as reporting "once a week," "a few times a week," or "everyday" on either the emotional exhaustion or depersonalization domains of the Maslach Burnout Inventory. Two open-ended questions were added to the survey for the Danish urologists, these were then qualitatively analyzed using thematic analysis. Categorial variables were compared using Chi square analysis. RESULTS: The response rate was 193 of 387 (49.9%) for the Danish urologists and 43 of 64 (67.1%) among American urologists. The prevalence of burnout for the American and Danish cohorts was identified in 4 (44.4%) of the American residents and 10 (32.3%) of the American attendings compared to 2 (3%) of Danish residents and 16 (12.7%) of Danish attendings. The difference in rate of burnout between Danish residents and attendings was statistically significant (P= .03). Burnout was statistically significantly different between American and Danish residents (P<.01) and attendings (P <.01). There was a statistically significant difference in rates of burnout between American and the Danish female urologists (P = .02) and similarly among male urologists (P <.01). CONCLUSION: This study demonstrated low rates of burnout among Danish urologists and a significant difference in burnout between residents and attendings from Michigan compared to Danish residents and attendings.


Asunto(s)
Agotamiento Profesional/epidemiología , Urología , Adolescente , Adulto , Anciano , Dinamarca/epidemiología , Femenino , Humanos , Masculino , Michigan/epidemiología , Persona de Mediana Edad , Prevalencia , Adulto Joven
20.
Reprod Fertil Dev ; 22(4): 625-33, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20353722

RESUMEN

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.


Asunto(s)
Bovinos/fisiología , Embrión de Mamíferos/fisiología , Estratos Germinativos/fisiología , Animales , Bovinos/embriología , Embrión de Mamíferos/citología , Desarrollo Embrionario/fisiología , Femenino , Estratos Germinativos/ultraestructura , Inmunohistoquímica/veterinaria , Microscopía Electrónica de Transmisión/veterinaria , Factor 3 de Transcripción de Unión a Octámeros/fisiología , alfa-Fetoproteínas/fisiología
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