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1.
Animals (Basel) ; 14(1)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38200896

RESUMEN

Two trials were conducted to evaluate the effect of a garlic and citrus extract supplement (GCE) on the milk production performance and carbon footprint of grazing dairy cows in a Chilean commercial farm. A total of 36 early- to mid-lactation and 54 late-lactation Irish Holstein-Friesian cows were used in Trial 1 and Trial 2, respectively. In both trials, the cows were reared under grazing conditions and offered a supplementary concentrate without or with GCE (33 g/cow/d) for 12 weeks. The concentrate was fed in the afternoon when the cows visited the milking parlour. Consequently, the results of milk production performance in these trials were used to determine the effect of feeding with GCE on the carbon footprint (CFP) of milk using a life cycle assessment (LCA) model. In Trial 1 and Trial 2, feeding with GCE increased estimated dry matter intake (DMI, kg/d) by 8.15% (18.4 vs. 19.9) and 15.3% (15.0 vs. 17.3), energy-corrected milk (ECM, kg/d) by 11.4% (24.5 vs. 27.3) and 33.5% (15.5 vs. 20.7), and feed efficiency (ECM/DMI) by 3.03% (1.32 vs. 1.36) and 17.8% (1.01 vs. 1.19), respectively. The LCA revealed that feeding with GCE reduced the emission intensity of milk by 8.39% (1.55 vs. 1.42 kg CO2-eq/kg ECM). Overall, these results indicate that feeding with GCE improved the production performance and CFP of grazing cows under the conditions of the current trials.

2.
Anim Reprod Sci ; 246: 106848, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34556396

RESUMEN

Conventional in vitro fertilization is not efficacious when working with equine gametes. Although stallion spermatozoa bind to the zona pellucida in vitro, these gametes fail to initiate the acrosome reaction in the vicinity of the oocyte and cannot, therefore, penetrate into the perivitelline space. Failure of sperm penetration most likely relates to the absence of optimized in vitro fertilization media containing molecules essential to support stallion sperm capacitation. In vivo, the female reproductive tract, especially the oviductal lumen, provides an environmental milieu that appropriately regulates interactions between the gametes and promotes fertilization. Identifying these 'fertilization supporting factors' would be a great contribution for development of equine in vitro fertilization media. In this review, a description of the current understanding of the interactions stallion spermatozoa undergo during passage through the female genital tract, and related specific molecular changes that occur at the sperm plasma membrane is provided. Understanding these molecular changes may hold essential clues to achieving successful in vitro fertilization with equine gametes.


Asunto(s)
Semen , Capacitación Espermática , Caballos , Animales , Masculino , Femenino , Capacitación Espermática/fisiología , Interacciones Espermatozoide-Óvulo/fisiología , Reacción Acrosómica/fisiología , Zona Pelúcida/metabolismo , Espermatozoides/fisiología
3.
Nanoscale ; 14(2): 506-514, 2022 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-34913938

RESUMEN

Lipid nanoemulsions are promising nanomaterials for drug delivery applications in food, pharmaceutical and cosmetic industries. Despite the noteworthy commercial interest, little is known about their supramolecular organization, especially about how such multicomponent formulations interact with cell membranes. In the present work, coarse-grained molecular dynamics simulations have been employed to study the self-assembly of a 15-component lipid nanoemulsion droplet containing vitamins A and E for skin delivery. Our results display aspects of the unique "onion-like" agglomeration between the chemical constituents in the different layers of the lipid nanodroplet. Vitamin E molecules are more concentrated in the center of the droplet together with other hydrophobic constituents such as the triglycerides with long tails. On the other hand, vitamin A occupies an intermediate layer between the core and the co-emulsifier surface of the nanodroplet, together with lecithin phospholipids. Coarse-grained molecular dynamics simulations were also performed to provide insight into the first steps involved in absorption and penetration of the nanodroplet through skin membrane models, representing an intracellular (hair follicle infundibulum) and intercellular pathway (stratum corneum) through the skin. Our data provide a first view on the complex organization of commercial nanoemulsion and its interaction with skin membranes. We expect our results to open the way towards the rational design of such nanomaterials.


Asunto(s)
Absorción Cutánea , Vitaminas , Sistemas de Liberación de Medicamentos , Emulsiones , Piel/metabolismo
4.
Anim Reprod ; 15(Suppl 1): 737-750, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-36249840

RESUMEN

In the cow a major characteristic of metabolic stress is an elevated level of plasma free fatty acid, due to increased lipid mobilization from adipose tissue. Elevated levels of free fatty acids in blood (complexed to albumin) are associated with increased lipotoxicity in non-adipose tissue. An overview is provided on the negative impact of free fatty acids and the metabolic stress imposed on the oocyte and early embryo and thus on bovine fertility. There is increasing evidence that in vitro as well as in vivo the elevated levels of free fatty acids in blood during metabolic stress can severely hamper oocyte and embryo development. However, fatty acids do also form an essential nutrient source for the oocyte and embryo, which indicates that these good and bad effects of fatty acids should be in subtle balance to optimize the developmental competence of the oocyte and embryo.

5.
Anim. Reprod. (Online) ; 15(supl. 1): 737-750, set. 2018. ilus
Artículo en Inglés | VETINDEX | ID: biblio-1461395

RESUMEN

In the cow a major characteristic of metabolic stress is an elevated level of plasma free fatty acid, due to increased lipid mobilization from adipose tissue. Elevated levels of free fatty acids in blood (complexed to albumin) are associated with increased lipotoxicity in non-adipose tissue. An overview is provided on the negative impact of free fatty acids and the metabolic stress imposed on the oocyte and early embryo and thus on bovine fertility. There is increasing evidence that in vitro as well as in vivo the elevated levels of free fatty acids in blood during metabolic stress can severely hamper oocyte and embryo development. However, fatty acids do also form an essential nutrient source for the oocyte and embryo, which indicates that these good and bad effects of fatty acids should be in subtle balance to optimize the developmental competence of the oocyte and embryo.


Asunto(s)
Femenino , Animales , Bovinos , Bovinos/metabolismo , Folículo Ovárico , Oocitos/crecimiento & desarrollo , Ácidos Grasos
6.
Anim. Reprod. ; 15(supl. 1): 737-750, set. 2018. ilus
Artículo en Inglés | VETINDEX | ID: vti-740154

RESUMEN

In the cow a major characteristic of metabolic stress is an elevated level of plasma free fatty acid, due to increased lipid mobilization from adipose tissue. Elevated levels of free fatty acids in blood (complexed to albumin) are associated with increased lipotoxicity in non-adipose tissue. An overview is provided on the negative impact of free fatty acids and the metabolic stress imposed on the oocyte and early embryo and thus on bovine fertility. There is increasing evidence that in vitro as well as in vivo the elevated levels of free fatty acids in blood during metabolic stress can severely hamper oocyte and embryo development. However, fatty acids do also form an essential nutrient source for the oocyte and embryo, which indicates that these good and bad effects of fatty acids should be in subtle balance to optimize the developmental competence of the oocyte and embryo.(AU)


Asunto(s)
Animales , Femenino , Bovinos , Folículo Ovárico , Oocitos/crecimiento & desarrollo , Bovinos/metabolismo , Ácidos Grasos
7.
J Stroke Cerebrovasc Dis ; 22(6): 764-74, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22516427

RESUMEN

This study examined the baseline characteristics, racial/ethnic differences, and geographic differences among participants in the Secondary Prevention of Small Subcortical Strokes (SPS3) study. The SPS3 trial enrolled patients who experienced a symptomatic small subcortical stroke (lacunar stroke) within the previous 6 months and an eligible lesion on detected on magnetic resonance imaging. The patients were randomized, in a factorial design, to antiplatelet therapy (aspirin 325 mg daily plus clopidogrel 75 mg daily vs aspirin 325 mg daily plus placebo) and to one of two levels of systolic blood pressure targets ("intensive" [<130 mmHg] or "usual" [130-149 mmHg]). A total of 3020 participants were recruited from 81 clinical sites in 8 countries. In this cohort, the mean age was 63 years, 63% were men, 75% had a history of hypertension, and 37% had diabetes. The racial distribution was 51% white, 30% Hispanic, and 16% black. Compared with white subjects, black subjects were younger (mean age, 58 years vs 64 years; P <.001) and had a higher prevalence of hypertension (87% vs 70%; P <.001). The prevalence of diabetes was higher in the Hispanic and black subjects compared with the white subjects (42% and 40% vs 32%; both P <.001). Tobacco smoking at the time of qualifying stroke was much more frequent in the Spanish participants than in subjects from North America and from Latin America (32%, 22%, and 9%, respectively; P <.001). Mean systolic blood pressure at study entry was 4 mmHg lower in the Spanish subjects compared with the North American subjects (P <.01). The SPS3 cohort is the largest magnetic resonance imaging-defined series of patients with S3. Among the racially/ethnically diverse SPS3 participants, important differences in patient features and vascular risk factors could influence prognosis for recurrent stroke and response to interventions.


Asunto(s)
Antihipertensivos/administración & dosificación , Etnicidad , Inhibidores de Agregación Plaquetaria/administración & dosificación , Grupos Raciales , Prevención Secundaria/métodos , Accidente Cerebrovascular/etnología , Accidente Cerebrovascular/prevención & control , Negro o Afroamericano , Anciano , Aspirina/administración & dosificación , Presión Sanguínea/efectos de los fármacos , Distribución de Chi-Cuadrado , Clopidogrel , Diabetes Mellitus/etnología , Esquema de Medicación , Quimioterapia Combinada , Femenino , Hispánicos o Latinos , Humanos , Hipertensión/etnología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , América del Norte/epidemiología , Prevalencia , Factores de Riesgo , Fumar/efectos adversos , Fumar/etnología , América del Sur/epidemiología , España/epidemiología , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/fisiopatología , Ticlopidina/administración & dosificación , Ticlopidina/análogos & derivados , Factores de Tiempo , Resultado del Tratamiento , Población Blanca
8.
Theriogenology ; 59(8): 1693-705, 2003 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-12566145

RESUMEN

Many theories have been postulated concerning the possible effects of cryopreservation on spermatozoa, including suggestions the freeze-thawing process produces membranes that have greater fluidity and are more fusogenic, thus inducing changes similar to those of capacitation. The main objectives of this study were to determine at what stage of the freeze-thaw process membrane changes occur and whether evaluation with chlortetracycline (CTC) stain could predict the freezability of stallion sperm. Sperm viability and state of capacitation were simultaneously evaluated using CTC and Hoechst 33258 (H258) techniques. Membrane function was evaluated using the hypo-osmotic swelling test (HOS) and progressive motility (PM) was evaluated under light microscopy at each stage of a freeze-thaw protocol. Evaluated were raw semen; after dilution and centrifugation; after redilution and equilibration at room temperature; after cooling to 5 degrees C; after super cooling to -15 degrees C; and after thawing. The most pronounced functional damage to membranes and the greatest decrease in PM occurred in samples of all stallions after thawing (P<0.05). Cryopreservation, as evaluated by CTC/H258 staining, significantly (P<0.05) affected sperm membrane integrity after centrifugation, after redilution and equilibration at room temperature and after cooling to 5 degrees C. The HOS and H258 tests gave similar results (R values of approximately 0.75) and correlated inversely with the number of live noncapacitated sperm cells (R values of approximately -0.75). Remarkably, the subpopulation of capacitated live cells was unaffected in all freeze-thawing steps and the number of live acrosome reacted cells increased by a factor of 4. However, it was not possible to determine whether the changing CTC patterns reflect a true capacitation phenomenon or an intermediate destabilized state of the sperm cell membrane. This increase may indicate that the subpopulation of functional sperm cells capable of binding to the zona pellucida increases after freeze-thawing despite the deteriorative effect of this procedure for the entire live sperm population.


Asunto(s)
Membrana Celular/ultraestructura , Criopreservación/veterinaria , Caballos , Calor , Preservación de Semen/veterinaria , Espermatozoides/ultraestructura , Acrosoma/ultraestructura , Animales , Bisbenzimidazol , Muerte Celular , Clortetraciclina , Colorantes Fluorescentes , Masculino , Capacitación Espermática , Coloración y Etiquetado
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