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1.
J Thorac Imaging ; 39(2): 101-110, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37265250

RESUMEN

PURPOSE: The purpose of this study was to investigate the effect of integrated evaluation of resting static computed tomography perfusion (CTP) and coronary computed tomography angiography (CCTA)-derived fractional flow reserve (FFR CT ) on therapeutic decision-making and predicting major adverse cardiovascular events (MACEs) in patients with suspected coronary artery disease. MATERIALS AND METHODS: In this post hoc analysis of a prospective trial of CCTA in patients assigned to either CCTA or CCTA plus FFR CT arms, 500 patients in the CCTA plus FFR CT arm were analyzed. Both resting static CTP and FFR CT were evaluated by using the conventional CCTA. Perfusion defects in the myocardial segments with ≥50% degree of stenosis in the supplying vessels were defined as resting static CTP positive, and any vessel with an FFR CT value of ≤0.80 was considered positive. Patients were divided into 3 groups: (1) negative CTP-FFR CT match group (resting static CTP-negative and FFR CT -negative group); (2) mismatch CTP-FFR CT group (resting static CTP-positive and FFR CT -negative or resting static CTP-negative and FFR CT -positive group); and (3) positive CTP-FFR CT match group (resting static CTP-positive and FFR CT -positive group). We compared the revascularization-to-invasive coronary angiography ratio and the MACE rate among 3 subgroups at 1- and 3-year follow-ups. The adjusted Cox hazard proportional model was used to assess the prognostic value of FFR CT and resting static CTP to determine patients at risk of MACE. RESULTS: Patients in the positive CTP-FFR CT match group were more likely to undergo revascularization at the time of invasive coronary angiography compared with those in the mismatch CTP-FFR CT group (81.4% vs 57.7%, P =0.033) and the negative CTP-FFR CT match group (81.4% vs 33.3%, P= 0.001). At 1- and 3-year follow-ups, patients in the positive CTP-FFR CT match group were more likely to have MACE than those in the mismatch CTP-FFR CT group (10.5% vs 4.2%, P= 0.046; 35.6% vs 9.4%, P <0.001) and the negative CTP-FFR CT match group (10.5% vs 0.9%, P <0.001; 35.6% vs 5.4%, P <0.001). A positive CTP-FFR CT match was strongly related to MACE at 1-year (hazard ratio=8.06, P= 0.003) and 3-year (hazard ratio=6.23, P <0.001) follow-ups. CONCLUSION: In patients with suspected coronary artery disease, the combination of FFR CT with resting static CTP could guide therapeutic decisions and have a better prognosis with fewer MACE in a real-world scenario.


Asunto(s)
Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Reserva del Flujo Fraccional Miocárdico , Imagen de Perfusión Miocárdica , Humanos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/terapia , Imagen de Perfusión Miocárdica/métodos , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Tomografía Computarizada por Rayos X/métodos , Ensayos Clínicos como Asunto
2.
Free Radic Biol Med ; 194: 23-32, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36436728

RESUMEN

Patients with heart failure with reduced ejection fraction (HFrEF) experience diaphragm weakness that contributes to the primary disease symptoms of fatigue, dyspnea, and exercise intolerance. Weakness in the diaphragm is related to excessive production of reactive oxygen species (ROS), but the exact source of ROS remains unknown. NAD(P)H Oxidases (Nox), particularly the Nox2 and 4 isoforms, are important sources of ROS within skeletal muscle that contribute to optimal cell function. There are reports of increased Nox activity in the diaphragm of patients and animal models of HFrEF, implicating these complexes as possible sources of diaphragm dysfunction in HFrEF. To investigate the role of these proteins on diaphragm weakness in HFrEF, we generated inducible skeletal muscle specific knockouts of Nox2 or Nox4 using the Cre-Lox system and assessed diaphragm function in a mouse model of HFrEF induced by myocardial infarction. Diaphragm maximal specific force measured in vitro was depressed by ∼20% with HFrEF. Skeletal muscle knockout of Nox4 provided full protection against the loss of maximal force (p < 0.01), while the knockout of Nox2 provided partial protection (7% depression, p < 0.01). Knockout of Nox2 from skeletal myofibers improved survival from 50 to 80% following myocardial infarction (p = 0.026). Our findings show an important role for skeletal muscle NAD(P)H Oxidases contributing to loss of diaphragm maximal force in HFrEF, along with systemic pathophysiological responses following myocardial infarction.


Asunto(s)
Insuficiencia Cardíaca , Infarto del Miocardio , Disfunción Ventricular Izquierda , Animales , Ratones , Diafragma , Insuficiencia Cardíaca/metabolismo , Ratones Noqueados , Músculo Esquelético/metabolismo , Infarto del Miocardio/metabolismo , NADPH Oxidasa 4/genética , NADPH Oxidasa 4/metabolismo , NADPH Oxidasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Volumen Sistólico/fisiología , Disfunción Ventricular Izquierda/metabolismo
3.
J Anim Sci ; 100(7)2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35772764

RESUMEN

This article provides a synopsis of the collection of papers provided by participants of the NE1727 Multistate project. Five reviews and thirteen primary research articles are included that provide contributions the group has made to understanding the role of the corpus luteum in reproduction, describing how the ovary influences fertility, delineating mechanisms controlling oocyte quality and early embryo development, and exploring new reproductive management schemes.


Asunto(s)
Cuerpo Lúteo , Reproducción , Animales , Femenino
4.
Biol Open ; 10(10)2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34719702

RESUMEN

Although derivation of naïve bovine embryonic stem cells is unachieved, the possibility for generation of bovine induced pluripotent stem cells (biPSCs) has been generally reported. However, attempts to sustain biPSCs by promoting self-renewal have not been successful. Methods established for maintaining murine and human induced pluripotent stem cells (iPSCs) do not support self-renewal of iPSCs for any bovid species. In this study, we examined methods to enhance complete reprogramming and concurrently investigated signaling relevant to pluripotency of the bovine blastocyst inner cell mass (ICM). First, we identified that forced expression of SV40 large T antigen together with the reprogramming genes (OCT4, SOX2, KLF4 and MYC) substantially enhanced the reprogramming efficacy of bovine fibroblasts to biPSCs. Second, we uncovered that TGFß signaling is actively perturbed in the ICM. Inhibition of ALK4/5/7 to block TGFß/activin/nodal signaling together with GSK3ß and MEK1/2 supported robust in vitro self-renewal of naïve biPSCs with unvarying colony morphology, steady expansion, expected pluripotency gene expression and committed differentiation plasticity. Core similarities between biPSCs and stem cells of the 16-cell-stage bovine embryo indicated a stable ground state of pluripotency; this allowed us to reliably gain predictive understanding of signaling in bovine pluripotency using systems biology approaches. Beyond defining a high-fidelity platform for advancing biPSC-based biotechnologies that have not been previously practicable, these findings also represent a significant step towards understanding corollaries and divergent aspects of bovine pluripotency. This article has an associated First Person interview with the joint first authors of the paper.


Asunto(s)
Masa Celular Interna del Blastocisto/fisiología , Diferenciación Celular/fisiología , Embrión de Mamíferos/citología , Células Madre Pluripotentes Inducidas/fisiología , Células Madre Pluripotentes/fisiología , Animales , Bovinos , Humanos , Ratones , Transducción de Señal , Sustento
5.
Science ; 368(6495)2020 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-32499413

RESUMEN

The miniaturization of semiconductor transistors has driven the growth in computer performance for more than 50 years. As miniaturization approaches its limits, bringing an end to Moore's law, performance gains will need to come from software, algorithms, and hardware. We refer to these technologies as the "Top" of the computing stack to distinguish them from the traditional technologies at the "Bottom": semiconductor physics and silicon-fabrication technology. In the post-Moore era, the Top will provide substantial performance gains, but these gains will be opportunistic, uneven, and sporadic, and they will suffer from the law of diminishing returns. Big system components offer a promising context for tackling the challenges of working at the Top.

6.
J Dairy Sci ; 103(5): 4765-4776, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32229118

RESUMEN

Dairy cows consume inadequate amounts of feed in early lactation and during conditions and diseases such as excessive fatness, heat stress, and infectious diseases. Affected cows often experience increases in plasma concentrations of acute phase proteins consistent with the negative effect of inflammation on appetite. The acute phase protein orosomucoid 1 (ORM1), also known as alpha-1-acid glycoprotein, was recently reported to reduce appetite in the mouse through its ability to bind the full-length leptin receptor (Ob-Rb) and activate appetite-suppressing signal transducer and activator of transcription 3 (STAT3) signaling. These observations raise the possibility that ORM1 exerts appetite-suppressing effects in dairy cattle during periods of increased inflammatory tone. The applicability of this model was assessed in 2 ways. First, we asked whether ORM1 is regulated during periods of inadequate appetite such as the transition from late pregnancy to early lactation and periods of increased inflammatory tone. Plasma ORM1 was invariant in late pregnancy but increased 2.5-fold between parturition and d 7 of lactation. Gene expression studies showed that liver was the major source of this elevation with little contribution by adipose tissue or mammary gland. Additional studies showed that plasma ORM1 was not increased further by excessive fatness or by reproductive dysfunction in early lactation and was completely unresponsive to inflammatory stimuli such as heat stress or intravascular administration of the endotoxin lipopolysaccharide during established lactation. Second, we tested the ability of ORM1 to trigger STAT3 signaling through Ob-Rb using Chinese hamster ovary K1 (CHO-K1) cells transfected with a STAT3 expression plasmid. In this configuration, CHO-K1 cells did not express Ob-Rb and were incapable of leptin-induced STAT3 phosphorylation. Leptin responsiveness was conferred by co-transfecting with bovine Ob-Rb, with leptin causing increases of 5.7-fold in STAT3 phosphorylation and 2.1-fold in the expression of the STAT3-dependent gene, SOCS3. In contrast, neither bovine or human ORM1 triggered STAT3 phosphorylation irrespective of dose and period of incubation tested. In summary, bovine ORM1 is not increased during periods of increased inflammatory tone except in early lactation and is incapable of Ob-Rb-dependent STAT3 signaling. Overall, these data are inconsistent with ORM1 mediating the appetite-suppressing effects of inflammation in cattle through Ob-Rb.


Asunto(s)
Regulación del Apetito/fisiología , Bovinos/metabolismo , Lactancia/fisiología , Orosomucoide/metabolismo , Receptores de Leptina/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Proteínas de Fase Aguda/metabolismo , Tejido Adiposo/metabolismo , Animales , Células CHO , Cricetinae , Cricetulus , Femenino , Leptina/metabolismo , Embarazo , Regulación hacia Arriba
7.
Domest Anim Endocrinol ; 71: 106385, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31726391

RESUMEN

Most dairy cows develop a dominant follicle within two weeks postpartum, but 60% of these follicles fail to ovulate. In a previous study, we determined that cows destined to ovulate have higher LH pulse frequency and circulating estradiol. The latter characteristic provided a method for distinguishing ovulatory from nonovulatory follicles during development and we found that nonovulatory follicles have lower estradiol and androstenedione in their follicular fluid. We hypothesized that lower LH pulse frequency impairs androgen production by theca cells of nonovulatory cows, reducing their ability to make estradiol. In the present study, we applied our method for predicting follicle fate to collect dominant follicles from predicted ovulatory (n = 7) and nonovulatory (n = 3) follicles. Theca and granulosa cells were separated and cultured in the absence or presence of LH, FSH, and/or testosterone for three days, with daily collection of culture medium for steroid RIAs. Estradiol and progesterone production by granulosa cells were not different between ovulatory and nonovulatory follicles. By contrast, overall androstenedione production by theca cells from ovulatory follicles was significantly higher compared with nonovulatory follicles on all three days of culture and, as culture progressed, theca from nonovulatory follicles had increasingly poorer responses to LH. In the same cultures, the progesterone production by theca cells was similar in ovulatory and nonovulatory groups. In support of our hypothesis, the results show that estradiol production by granulosa cells from nonovulatory follicles is robust when androgen substrate is present, but that thecal androgen production in response to LH is impaired. This suggests that the initial defect in steroidogenesis in dominant follicles that fail to ovulate postpartum is lower production of androgen by theca cells.


Asunto(s)
Andrógenos/metabolismo , Andrógenos/farmacología , Bovinos/fisiología , Hormona Luteinizante/farmacología , Células Tecales/efectos de los fármacos , Células Tecales/metabolismo , Animales , Células Cultivadas , Relación Dosis-Respuesta a Droga , Estradiol/metabolismo , Femenino , Células de la Granulosa/metabolismo , Hormona Luteinizante/administración & dosificación , Periodo Posparto , Embarazo , Progesterona/metabolismo
8.
Anim Reprod Sci ; 211: 106206, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31785637

RESUMEN

This study was conducted to evaluate associations of polymorphisms in the genes for the growth hormone receptor (GHR), insulin-like growth factor I (IGF-I) and signal transducer and activator of transcription 5A (STAT5A) with serum concentrations of IGF-I, reproductive performance and milk production of postpartum Holstein dairy cows. Days from calving to first ovulation (DTO) and calving to conception interval (CCI) were evaluated in 95 Holstein cows. Serum concentrations of IGF-I and ß-hydroxybutyrate (BHBA) were quantified in samples collected in sequential blood collections. Genotyping of the IGF-I and STAT5A genes was performed. The IGF-I polymorphism distribution was 35.9% CC, 46.1% CT and 18% TT. The IGF-I concentrations in circulation were greater in cows of the TT compared with both the CT and CC groups (P < 0.05). Genotype had a linear association (P < 0.05) with DTO and CCI, which were less for cows of the TT group. There was no association of STAT5A BstEII on serum IGF-I or reproductive variables (P> 0.05). When combining the GHR AluI T allele, obtained in a previous study, and the IGF-I SnaBI T allele from the current study, for the same cows, there were additive associations of both with serum IGF-I, BHBA, number of services per conception, DTO and CCI (P < 0.05). Thus, the IGF-1 SnaBI TT appears to be associated with fewer DTO and lesser CCI of lactating dairy cows and had an additive association with the GHR AluI T allele on indicators for improvement of fertility.


Asunto(s)
Bovinos/fisiología , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Polimorfismo de Nucleótido Simple , Receptores de Somatotropina/genética , Factor de Transcripción STAT5/genética , Animales , Bovinos/genética , Femenino
9.
Theriogenology ; 125: 302-309, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30504072

RESUMEN

Paraoxonase 1 (PON1) is a negative acute phase plasma protein synthesized by the liver that has anti-oxidant activity. The aim of this study was to evaluate the association of single nucleotide polymorphisms (SNPs) in the PON1 promoter region with plasma PON1 activity and fertility in Holstein dairy cows. Sixty-eighty Holstein cows were used in this initial investigative study. Blood samples were collected weekly beginning 28 days prior to expected calving, twice weekly in week 1 and 2 postpartum, and then once weekly through 6 weeks postpartum for plasma PON1 activity analysis. Cows were synchronized for ovulation and timed AI at 63-70 DIM using an Ovsynch program. Pregnancy diagnosis was confirmed by rectal palpation and reproductive performance data was recorded until 210 DIM. DNA was extracted from blood of each cow and a fragment of proximal PON1 gene promoter was sequenced. Seven single nucleotide polymorphisms (SNPs) were identified in the promoter region of the PON1 gene at positions -22, -105, -176, -221, -392, -611 and -676, six of which were significantly associated with plasma PON1 activity level. The SNPs -221 and -392 were significantly associated with both plasma PON1 activity and the calving to conception interval (P < 0.05) with no significant effect on calving to first ovulation interval. In conclusion, the genotypes associated with higher plasma PON1 activity in SNP locations -221 and -392 were also associated with a reduced calving to conception interval in this study set of cows. These SNPs may provide novel genetic markers for improved fertility in future larger studies in dairy cows.


Asunto(s)
Arildialquilfosfatasa/metabolismo , Bovinos/genética , Bovinos/fisiología , Fertilidad/genética , Polimorfismo de Nucleótido Simple , Animales , Antioxidantes/metabolismo , Arildialquilfosfatasa/genética , Sincronización del Estro , Femenino , Regulación Enzimológica de la Expresión Génica , Genotipo , Inseminación Artificial , Periodo Posparto , Embarazo
10.
J Dairy Sci ; 100(11): 9418-9427, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28843695

RESUMEN

In transition dairy cows, plasma levels of the insulin-sensitizing hormone adiponectin fall to a nadir at parturition and recover in early lactation. The transition period is also characterized by rapid changes in metabolic and hormonal factors implicated in other species as positive regulators of adiponectin production (i.e., negative energy balance, lipid mobilization) and others as negative regulators (i.e., reduced leptin and insulin and increased growth hormone and plasma fatty acids). To assess the role of onset of negative energy balance and lipid mobilization after parturition, dairy cows were either milked thrice daily (lactating) or never milked (nonlactating) for up to 4 wk after parturition. Plasma adiponectin was 21% higher across time in nonlactating than lactating cows. Moreover, nonlactating cows recovered plasma adiponectin at similar rates as lactating cows even though they failed to lose body condition. Next, we assessed the ability of individual hormones to alter plasma adiponectin in transition dairy cows. In the first experiment, dairy cows received a constant 96-h intravenous infusion of either saline or recombinant human leptin starting on d 8 of lactation. In the second experiment, dairy cows were studied in late pregnancy (LP, starting on prepartum d -31) and again in early lactation (EL, starting on d 7 postpartum) during a 66-h period of basal sampling followed by 48 h of hyperinsulinemic-euglycemia. In the third experiment, cows were studied either in LP (starting on d -40 prepartum) or EL (starting on d 7 postpartum) during a 3-h period of basal sampling followed by 5 d of bovine somatotropin treatment. Plasma adiponectin was reduced by an average of 21% in EL relative to LP in these experiments, but neither leptin, insulin, or growth hormone treatment affected adiponectin in LP or EL. Finally, the possibility that plasma fatty acids repress plasma adiponectin was evaluated by intravenous infusion of a lipid emulsion in nonpregnant, nonlactating cows in the absence or presence of glucagon for 16 consecutive hours. The intralipid infusion increased plasma fatty acid concentration from 102 to over 570 µM within 3 h but had no effect on plasma adiponectin irrespective of presence or absence of glucagon. Overall, these data suggest that energy balance around parturition may regulate plasma adiponectin but do not support roles for lipid mobilization or sustained changes in the plasma concentration of leptin, insulin, growth hormone, or fatty acids.


Asunto(s)
Adiponectina/sangre , Bovinos/fisiología , Metabolismo Energético/fisiología , Lactancia/fisiología , Adiponectina/metabolismo , Animales , Femenino , Glucagón , Humanos , Insulina/sangre , Leptina/sangre , Leche/metabolismo , Parto/sangre , Periodo Posparto/sangre , Embarazo
11.
J Dairy Sci ; 100(7): 5888-5898, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28456404

RESUMEN

The objective of the study was to evaluate the effect of prepartum and postpartum (PP) supplementation with 2 isomers of conjugated linoleic acid (CLA) on reproductive parameters and some related metabolic factors in dairy cows. High-producing, multiparous Holstein Friesian cows (n = 60) were allotted to 3 treatment groups: the CLA1 group (n = 20) was supplemented with 70 g of lipid-encapsulated CLA providing 7 g each of cis-9,trans-11 and trans-10,cis-12 CLA from d 21 (d 21) before expected calving until d 7 after artificial insemination (AI), that is, until 77 to 91 d PP; the CLA2 group (n = 20) was supplemented with the same amount of CLA beginning at calving until d 7 after AI; and the control group (n = 20) received an isocaloric, isonitrogenous, and isolipidic diet. Blood samples were taken weekly to measure glucose, insulin, insulin-like growth factor-I (IGF-I), and leptin. Liver biopsy was performed in 10 cows per group for growth hormone receptor 1A and IGF-I mRNA analyses. At d 49 to 63 PP, ovulation was synchronized with the Pre-Synch protocol followed by fixed-time AI. Milk progesterone was monitored from calving until d 35 post-AI. Cows returning to estrus following AI were inseminated. Supplementation with CLA before calving improved the recovery of plasma leptin levels in the early PP period (from the day of calving until wk 3 PP; treatment effect). Later PP (wk 5), plasma IGF-I, and leptin remained significantly higher in both CLA1 and CLA2 groups compared with control, although hepatocellular IGF-I mRNA was not different among groups. Plasma IGF-I levels remained higher in both CLA-treated groups on the day of AI. Growth hormone receptor 1A mRNA levels in hepatic tissue decreased in all groups, reaching a nadir in the first week PP. Days to first PP ovulation did not differ between groups; however, both supplemented groups conceived earlier compared with control (d 97 ± 19, d 97 ± 23, and d 113 ± 30 for CLA1, CLA2, and control, respectively). Plasma progesterone concentration was higher in both supplemented groups on d 2 to 5 following the synchronized ovulation than in controls. We concluded that CLA supplementation around calving alters PP metabolic signals as reflected by higher plasma leptin and IGF-I levels. Conjugated linoleic acid stimulated early luteal function and reduced the PP interval to conception.


Asunto(s)
Bovinos , Hormona del Crecimiento/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/efectos de los fármacos , Ácidos Linoleicos Conjugados/administración & dosificación , Reproducción/efectos de los fármacos , Animales , Femenino , Lactancia , Lípidos , Leche , Periodo Posparto , Embarazo
12.
PLoS One ; 12(5): e0177356, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28542500

RESUMEN

The objective of this study was to determine the effects of uterine and systemic inflammatory responses to uterine bacterial contamination at calving in dairy cows on the growth and ovulatory outcomes of the first dominant follicle postpartum. Ovulatory capability of the first dominant follicle postpartum was predicted in 53 multiparous cows by using a combination of follicle growth characteristics and circulating estradiol concentrations. Endotoxin levels were assayed in follicular fluid samples that were aspirated the day after ovulatory outcome prediction. Plasma levels of haptoglobin, a proinflammatory acute phase protein, and paraoxonase, a negative acute phase protein were determined. Uterine bacteria and inflammation were evaluated in three uterine fluid samples from each cow collected on the day of calving, the day after follicle aspiration, and at 35 days postpartum. Cows that had a strong initial uterine inflammatory response (robust recruitment of polymorphonuclear leukocytes of ≥ 35% and cows with uterine pH < 8.5 on the day of calving) were more likely to have an ovulatory first dominant follicle. Follicular fluid endotoxin levels were higher in non-ovulatory cows compared with ovulatory cows. Endotoxin levels in circulation were not different between ovulatory groups but were higher prepartum than on day 7 and 14 postpartum. Systemic inflammation characterized by elevated haptoglobin concentrations was higher in non-ovulatory cows despite similar bacterial contamination and circulating endotoxin levels. Paraoxonase activity in follicular fluid was significantly associated with the paraoxonase activity in plasma, however, plasma paraoxonase concentrations were not different between non-ovulatory and ovulatory cows. Cows with a higher uterine bacterial load on the day of calving had slower ovarian follicle growth. In summary, a robust uterine inflammatory response on the day of calving was positively associated with ovarian function while elevated systemic inflammation during the early postpartum period was negatively associated with the ovulatory status of the first dominant follicle postpartum.


Asunto(s)
Industria Lechera , Folículo Ovárico/fisiopatología , Periodo Posparto/fisiología , Enfermedades Uterinas/veterinaria , Animales , Bovinos , Femenino , Inflamación/fisiopatología , Inflamación/veterinaria , Ovulación , Enfermedades Uterinas/fisiopatología
13.
Reprod Domest Anim ; 51(5): 827-30, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27453486

RESUMEN

Paraoxonase-1 (PON1) is an enzyme found in serum and follicular fluid that protects cell membrane and circulating lipids against oxidative damage. The aims of this study were to measure the direct effects of recombinant PON1 (rPON1) on bovine oocyte maturation at the molecular level (gene expression) and to measure the carry-over effects of PON1 on pre-implantation embryo development in vitro. COCs were submitted to IVM with the addition of 0.0, 0.02, 0.04 and 0.08 mg ml(-1) of rPON1, corresponding to an average PON1 arylesterase enzyme activity of 2.2 ± 0.4, 15.5 ± 1.5, 30.2 ± 3.0 and 57.9 ± 5.0 U ml(-1) , respectively. The results indicated that addition of rPON1 during IVM improved embryo development in a dose-dependent manner as D7 embryo development was 22.2%, 29.4%, 32.2% and 37.0% for the treatment groups, respectively (p = 0.02). In conclusion, addition of PON1 enzyme during IVM exerted dose-related positive effects on embryo development rates to blastocysts.


Asunto(s)
Arildialquilfosfatasa/farmacología , Bovinos/embriología , Técnicas de Cultivo de Embriones/veterinaria , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Animales , Medios de Cultivo , Células del Cúmulo/efectos de los fármacos , Embrión de Mamíferos/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos
14.
J Endocrinol ; 229(2): 145-57, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26957637

RESUMEN

Mammals meet the increased nutritional demands of lactation through a combination of increased feed intake and a collection of adaptations known as adaptive metabolism (e.g., glucose sparing via insulin resistance, mobilization of endogenous reserves, and increased metabolic efficiency via reduced thyroid hormones). In the modern dairy cow, adaptive metabolism predominates over increased feed intake at the onset of lactation and develops concurrently with a reduction in plasma leptin. To address the role of leptin in the adaptive metabolism of early lactation, we asked which adaptations could be countered by a constant 96-h intravenous infusion of human leptin (hLeptin) starting on day 8 of lactation. Compared to saline infusion (Control), hLeptin did not alter energy intake or milk energy output but caused a modest increase in body weight loss. hLeptin reduced plasma glucose by 9% and hepatic glycogen content by 73%, and these effects were associated with a 17% increase in glucose disposal during an insulin tolerance test. hLeptin attenuated the accumulation of triglyceride in the liver by 28% in the absence of effects on plasma levels of the anti-lipolytic hormone insulin or plasma levels of free fatty acids, a marker of lipid mobilization from adipose tissue. Finally, hLeptin increased the plasma concentrations of T4 and T3 by nearly 50% without affecting other neurally regulated hormones (i.e., cortisol and luteinizing hormone (LH)). Overall these data implicate the periparturient reduction in plasma leptin as one of the signals promoting conservation of glucose and energy at the onset of lactation in the energy-deficient dairy cow.


Asunto(s)
Lactancia/metabolismo , Leptina/sangre , Adaptación Fisiológica/efectos de los fármacos , Animales , Glucemia/metabolismo , Bovinos , Ingestión de Alimentos , Femenino , Hormona del Crecimiento/metabolismo , Humanos , Infusiones Intravenosas , Leptina/administración & dosificación , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Glucógeno Hepático/metabolismo , Hormona Luteinizante/metabolismo , Embarazo , Hormonas Tiroideas/sangre
15.
Biol Reprod ; 94(1): 18, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26632612

RESUMEN

Most dairy cows develop the first dominant follicle postpartum within 2 wk after calving, but only about 40% of these follicles produce sufficient estradiol to stimulate ovulation despite having normal ultrasound appearance and growth. This study aimed to characterize metabolic, endocrine, and follicular fluid profiles of cows in which the first dominant follicle postpartum will become ovulatory and those with nonovulatory follicles. Luteinizing hormone pulse frequency, follicular fluid androstenedione, and follicular fluid estradiol concentrations were lower in nonovulatory cows suggesting that the function of theca cells is impaired. In addition, nonovulatory cows had more severe negative energy balance and greater insulin resistance postpartum. This study describes for the first time the steroid hormone profile of early postpartum follicles and shows that a steroidogenic defect most likely occurs in theca cells limiting the amount of androgen precursor available for estradiol production that impairs their ovulatory outcome.


Asunto(s)
Folículo Ovárico/fisiología , Ovulación/fisiología , Periodo Posparto/fisiología , Androstenodiona/metabolismo , Animales , Metabolismo de los Hidratos de Carbono , Bovinos , Metabolismo Energético , Estradiol/metabolismo , Femenino , Fertilidad , Líquido Folicular/metabolismo , Prueba de Tolerancia a la Glucosa , Resistencia a la Insulina , Hormona Luteinizante/sangre , Proteínas/metabolismo , Células Tecales
16.
Brachytherapy ; 14(6): 766-72, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26489923

RESUMEN

PURPOSE: To determine whether a previously reported substratification system can be extrapolated to patients with high-risk prostate cancer treated with permanent interstitial brachytherapy. METHODS AND MATERIALS: Four hundred six National Comprehensive Cancer Network patients with high-risk prostate cancer treated with permanent prostate brachytherapy with or without supplemental external beam radiotherapy were stratified into good (prostate-specific antigen >20 or Gleason score ≥8 or ≥T3), intermediate (prostate-specific antigen >20 and ≥T3), and poor (Gleason score ≥8 with ≥1 additional high-risk feature) prognostic cohorts. Because of only 1 patient with intermediate high-risk disease, the analysis was performed on patients in the good and poor cohorts. Biochemical failure (BF), prostate cancer-specific mortality (PCSM), distant metastasis, and overall mortality were assessed as function of prognostic group. Multiple parameters were evaluated for impact on outcome. RESULTS: With a median followup time of 7.9 years, 10- and 14-year rates of BF and PCSM for the entire cohort were 7.8% and 3.7%, respectively. The BF rate was significantly greater in the poor prognostic category (16.8% vs. 7.8%, p = 0.041). The poor prognostic category was the strongest predictor of BF in univariate and multivariate analyses. No statistically significant differences in PCSM, distant metastasis, or overall mortality were identified between the good and poor prognostic categories. CONCLUSIONS: Patients with high-risk prostate cancer treated with a brachytherapy approach have excellent long-term biochemical control and cancer-specific survival. The poor prognostic high-risk category had a higher rate of BF compared with the good prognostic category without a higher rate of PCSM or distant metastasis.


Asunto(s)
Braquiterapia , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/radioterapia , Anciano , Estudios de Seguimiento , Humanos , Masculino , Clasificación del Tumor , Metástasis de la Neoplasia , Pronóstico , Neoplasias de la Próstata/mortalidad , Factores de Riesgo , Resultado del Tratamiento
17.
AJNR Am J Neuroradiol ; 36(7): 1303-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25857761

RESUMEN

BACKGROUND AND PURPOSE: The advent of modern neuroendovascular techniques has highlighted the need for a simple, effective, and reliable brain arteriovenous malformation endovascular grading scale. A novel scale of this type has recently been described. It incorporates the number of feeding arteries, eloquence, and the presence of an arteriovenous fistula component. Our aim is to assess the validity of this grading scale. MATERIALS AND METHODS: We retrospectively reviewed all suspected brain arteriovenous malformations at Massachusetts General Hospital from 2005 to 2013, identifying 126 patients who met the inclusion criteria. Spearman correlations between endovascular and Spetzler-Martin grading scales and long-term outcomes were performed. Median endovascular grades were compared between treatment modalities and endovascular outcomes. Binary regression analysis was performed with major endovascular complications as a dichotomized dependent variable. Intraclass correlation coefficients were calculated for interobserver reliability of the endovascular grading scale. RESULTS: A significant Spearman correlation between the endovascular grade and the Spetzler-Martin grade was demonstrated (ρ = 0.5, P < .01). Differences in the median endovascular grades between the endovascular cure (median = 2) and endovascular complication groups (median = 4) (P < .05) and between the endovascular cure and successful multimodal treatment groups (median = 3) (P < .05) were demonstrated. The endovascular grade was the only independent predictor of complications (OR = 0.5, P < .01). The intraclass correlation coefficient of the endovascular grade was 0.71 (P < .01). CONCLUSIONS: Validation of a brain arteriovenous malformation endovascular grading scale demonstrated that endovascular grades of ≤II were associated with endovascular cure, while endovascular grades of ≤III were associated with multimodal cure or significant lesion reduction and favorable outcome. The endovascular grade provides useful information to refine risk stratification for endovascular and multimodal treatment.


Asunto(s)
Embolización Terapéutica/métodos , Procedimientos Endovasculares/métodos , Malformaciones Arteriovenosas Intracraneales/patología , Malformaciones Arteriovenosas Intracraneales/cirugía , Adulto , Anciano , Fístula Arteriovenosa/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
18.
J Dairy Sci ; 97(10): 6164-76, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25087029

RESUMEN

Conjugated linoleic acid (CLA) isomers can affect the lipid profile and signaling of cells and thereby alter their function. A total of 5,700 bovine oocytes were used in a structured series of experiments to test the effects of CLA cis-9,trans-11 and CLA trans-10,cis-12 in vitro. In experiment 1, high doses of each CLA isomer during in vitro maturation (IVM) were compared with high or low doses during the entire in vitro culture (IVC) of parthenogenetic embryos. High doses of the CLA isomers ranged from 50 to 200 µM and low doses were 15 and 25 µM. In experiment 2, the low doses of each CLA isomer were tested during IVM/IVC on embryos produced by in vitro fertilization (IVF). Experiment 3 compared the effects of 15 µM doses of each CLA isomer during IVM or IVC of IVF embryos. In experiment 4, post-rewarming survival rates and blastomere counts were assessed for embryos supplemented with each CLA isomer during IVM or for 36 h before vitrification. In experiment 1, when either CLA isomer was provided only during IVM, we observed no effects on overall rates of maturation, cleavage, or blastocysts (92.2 ± 1.6%, 78.3 ± 4.1%, and 28.9 ± 5.1%, respectively). However, high doses of each CLA isomer, but not low doses, during the entire embryo culture period decreased blastocyst rates (5-20%) in a dose-dependent manner. Cleavage rates improved with 15 or 50 µM CLA trans-10,cis-12. Progesterone concentrations in maturation media were significantly increased by high doses of each CLA isomer compared with control, but low doses of CLA isomers had no effect. In experiment 2 with IVF embryos, low doses of each CLA isomer did not alter cleavage rates (average 84.9 ± 1.9%) and only 25 µM CLA trans-10,cis-12 during IVC reduced blastocyst rates below those of controls (25.5 ± 2.1 vs. 38.2 ± 2.3%). The lipid content of embryos was increased and relative expression of the BIRC5 (baculoviral IAP repeat containing 5) gene was depressed by CLA trans-10,cis-12. In experiment 3, low doses (15µM) of each CLA isomer during IVC significantly reduced blastocyst rates (20.6 ± 2.4% and 27.7 ± 1.2% vs. 34.18 ± 1.2% for CLA trans-10,cis-12 and CLA cis-9,trans-11 compared with control, respectively) with less effect of each CLA during IVM. In experiment 4, adding 100 µM CLA cis-9,trans-11 during the final 36 h of culture resulted in a high survival rate after rewarming and culture, and the higher embryo blastomere count was comparable to that of control embryos not undergoing vitrification. In conclusion, supplementation with either CLA isomer did not improve embryo production, but inclusion of CLA cis-9,trans-11 before vitrification improved the quality of bovine IVF embryos after rewarming and culture.


Asunto(s)
Bovinos/embriología , Criopreservación/veterinaria , Fertilización In Vitro/veterinaria , Ácidos Linoleicos Conjugados/farmacología , Animales , Blastocisto/fisiología , Criopreservación/métodos , Técnicas de Cultivo de Embriones/métodos , Técnicas de Cultivo de Embriones/veterinaria , Desarrollo Embrionario/efectos de los fármacos , Técnicas de Maduración In Vitro de los Oocitos/métodos , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Isomerismo , Ácidos Linoleicos Conjugados/química , Lípidos/análisis , Oocitos/fisiología , Progesterona/análisis , Progesterona/fisiología
19.
J Dairy Sci ; 97(9): 5415-25, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24996269

RESUMEN

The objective was to evaluate the individual and combined effect of anovulation and cytological endometritis (CTE) on the reproductive performance of dairy cows. A total of 1,569 cows from 3 data sets were used. In data set 1, 403 Holstein cows from 5 dairies in New York were used. In data set 2, 750 Holstein cows from 2 dairies, one in Florida and one in California were used. In data set 3, 416 dairy cows, 165 Holsteins, 36 Jerseys, and 215 Holstein-Jersey crossbreeds from a grazing dairy in Florida were used. Cyclicity and CTE was determined at 35±3 (data set 2) or 49±3 d in milk (data sets 1 and 3). A variable (VarCycCTE) containing all 4 possible permutations between cyclicity (cyclic = Cyc; anovular = Anov) and CTE (present = CTE; absent = Healthy) was created. In the combined data set (sets 1, 2, and 3), pregnancy per artificial insemination (P/AI) diagnosed at 30 to 38 d after first AI was affected by VarCycCTE, with AnovCTE cows having decreased P/AI compared with CycHealthy cows (21.3 vs. 46.7%), whereas AnovHealthy (37.9%) and CycCTE cows (36.0%) had intermediate P/AI. Pregnancy per artificial insemination for the individual data sets and for pregnancy diagnosed at 63 to 74 d after artificial insemination followed a similar pattern. Pregnancy loss was not affected by VarCycCTE. Hazard of pregnancy up to 300 d in milk was affected by VarCycCTE in the combined data sets 1 and 2, with AnovCTE [hazard ratio (HR)=0.55], AnovHealthy cows (HR=0.71), and CycCTE (HR=0.8) having decreased hazard of pregnancy compared with CycHealthy cows. Median days open were 200, 159, 145, and 121 for AnovCTE, AnovHealthy, CycCTE, and CycHealthy, respectively. Hazard of pregnancy for the individual data sets followed a similar pattern. In summary, both anovulation and CTE were negatively associated with reproductive performance and, when combined, they had an additive negative effect.


Asunto(s)
Anovulación/veterinaria , Enfermedades de los Bovinos/fisiopatología , Bovinos , Endometritis/veterinaria , Reproducción , Animales , California , Dieta/veterinaria , Femenino , Florida , Vivienda para Animales , Inseminación Artificial/veterinaria , Leche , New York , Embarazo , Estudios Retrospectivos
20.
J Biol Chem ; 289(40): 27444-54, 2014 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-24936060

RESUMEN

Translocator protein (TSPO), previously known as the peripheral benzodiazepine receptor, is a mitochondrial outer membrane protein implicated as essential for cholesterol import to the inner mitochondrial membrane, the rate-limiting step in steroid hormone biosynthesis. Previous research on TSPO was based entirely on in vitro experiments, and its critical role was reinforced by an early report that claimed TSPO knock-out mice were embryonic lethal. In a previous publication, we examined Leydig cell-specific TSPO conditional knock-out mice that suggested TSPO was not required for testosterone production in vivo. This raised controversy and several questions regarding TSPO function. To examine the definitive role of TSPO in steroidogenesis and embryo development, we generated global TSPO null (Tspo(-/-)) mice. Contrary to the early report, Tspo(-/-) mice survived with no apparent phenotypic abnormalities and were fertile. Examination of adrenal and gonadal steroidogenesis showed no defects in Tspo(-/-) mice. Adrenal transcriptome comparison of gene expression profiles showed that genes involved in steroid hormone biosynthesis (Star, Cyp11a1, and Hsd3b1) were unchanged in Tspo(-/-) mice. Adrenocortical ultrastructure illustrated no morphological alterations in Tspo(-/-) mice. In an attempt to correlate our in vivo findings to previously used in vitro models, we also determined that siRNA knockdown or the absence of TSPO in different mouse and human steroidogenic cell lines had no effect on steroidogenesis. These findings directly refute the dogma that TSPO is indispensable for steroid hormone biosynthesis and viability. By amending the current model, this study advances our understanding of steroidogenesis with broad implications in biology and medicine.


Asunto(s)
Hormonas Esteroides Gonadales/biosíntesis , Receptores de GABA/genética , Receptores de GABA/metabolismo , Animales , Femenino , Células Intersticiales del Testículo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
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