Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 36
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-36011539

RESUMO

Semi-arid regions with little surface water commonly experience rapid water table decline rates. To hedge against the falling water table, production wells in central Mexico are commonly installed to depths of several hundred meters below the present water table and constructed as open boreholes or perforated casings across their entire length. Such wells represent highly conductive pathways leading to non-negligible flow across chemically distinct layers of an aquifer-a phenomenon known as ambient flow. The objectives of this study were to estimate the rate of ambient flow in seven production wells utilizing an end-member mixing model that is constrained by the observed transient chemical composition of produced water. The end-member chemical composition of the upper and lower layers of an urban aquifer that overlies geothermal heat is estimated to anticipate the future quality of this sole source of water for a rapidly growing urban area. The comprehensive water chemistry produced by seven continuously perforated municipal production wells, spanning three geologically unique zones across the city of San Miguel de Allende in Guanajuato State, was monitored during one day of pumping. The concentration of conservative constituents gradually converged on steady-state values. The model indicates that, relative to the lower aquifer, the upper aquifer generally has higher specific conductance (SC), chloride (Cl), nitrate (NO3), calcium (Ca), barium (Ba) and magnesium (Mg). The lower aquifer generally has a higher temperature, sodium (Na), boron (B), arsenic (As) and radon (Rn). Ambient flow ranged from 33.1 L/min to 225.7 L/min across the seven wells, but this rate for a given well varied depending on which tracer was used. This new 3D understanding of the chemical stratification of the aquifer suggests that as water tables continue to fall, concentrations of geothermally associated contaminants of concern will increase in the near future, potentially jeopardizing the safety of municipal drinking water.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Arsênio/análise , Monitoramento Ambiental , Água Subterrânea/química , Nitratos/análise , Óxidos de Nitrogênio , Poluentes Químicos da Água/análise , Qualidade da Água , Poços de Água
2.
Anim Sci J ; 92(1): e13646, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34655139

RESUMO

The present experiments on goats were conducted with the aim of verifying (a) whether the identity of the goat kids can affect the characteristics of milk let-down during suckling (Study 1) and (b) whether the presence of the goat kids may improve the milk let-down during hand milking (Study 2). In Study 1, 16 lactating goats with twins and 12 with single kids were used. Dams with single goat kids ejected more milk when suckling their kids at Days 5 and 20 of lactation, than when suckling aliens. Dams with twins ejected more milk when suckling their own kids than aliens only at Day 5 of lactation. Taking into account all the dams, they ejected more milk with more fat, protein, and lactose during suckling their own litter than when suckling aliens. In Study 2, when dams (n = 13) were hand milked in the presence of their own litter or in its absence, they ejected more milk with more fat, protein, and lactose than when milked in the presence of alien kids. We conclude that milk let-down in goats can be influenced by the type of stimuli applied or to which they are exposed to during suckling and milking.


Assuntos
Cabras , Lactação , Ejeção Láctea , Animais , Feminino , Lactose , Leite
3.
Animals (Basel) ; 11(2)2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33562447

RESUMO

This study examines the effectiveness of the photoperiod treatment (extra light for 88 days) to render the bucks sexually active during the seasonal anoestrous in order to induce a male effect, depending on the reproductive seasonality of the breed of the bucks used. In April, 57 anoestrous Blanca Andaluza does were distributed into four groups with three males each: 13 were exposed to control Murciano-Granadina bucks (lower seasonality); 15 were exposed to photostimulated Murciano-Granadina bucks; 14 were exposed to control Blanca Andaluza bucks (higher seasonality), and 15 were exposed to photostimulated Blanca Andaluza bucks. After male introduction, the sexual behaviour of the bucks was assessed, and harness marks recorded doe oestrous behaviour. Ovulation was confirmed from plasma progesterone, and the ovulation rate was assessed by transrectal ultrasonography. Fecundity, fertility, prolificacy and productivity were also determined. All of the does in all of the groups showed ovulation. Interaction between both sources of variation was observed: the percentage of females showing oestrous (p < 0.01) and productivity (p < 0.05) was the lowest in the Blanca Andaluza control group (50% and 0.36 ± 0.17 goat kids born/female, respectively). In conclusion, photoperiod-treated bucks efficiently induce a male effect, but photostimulation could be more necessary for breeds with deep seasonality.

4.
Water Res ; 185: 116257, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33086466

RESUMO

This study identifies causes of rising arsenic (As) concentrations over 17 years in an inter-montane aquifer system located just north of the Trans-Mexican-Volcanic-Belt in the Mesa central physiographic region that is extensively developed by long-screened production wells. Arsenic concentrations increased by more than 10 µg/L in 14% (3/22) of re-sampled wells. Similarly, in a larger scale analysis wherein As concentrations measured in 137 wells in 2016 were compared to interpolated, baseline concentrations from 246 wells in 1999, As concentrations rose more than 10 µg/L in 30% of wells. Between 1999 and 2016, the percentage of all wells sampled in each basin-wide sampling campaign exceeding the World Health Organization's 10 µg/L drinking water limit increased from 38 to 64%. Principal Components Analysis (PCA), step-wise multiple regression, and Random Forest modeling (RF) revealed that high As concentrations are closely associated with high pH and temperature, and high concentrations of fluoride (F), molybdenum (Mo), lithium (Li), sodium (Na) and silica (Si), but low calcium (Ca) and nitrate (NO3) concentrations. Pumping-induced mixing with hot, geothermally impacted groundwater generates alkaline water through hydrolysis of silicate minerals. The rising pH converts oxyanion sorption sites from positive to negative releasing As (and Mo) to pore waters. The negative correlation between nitrate and As concentrations can be explained by conservative mixing of shallow, young groundwater with geothermally influenced groundwater. Therefore water carrying an anthropogenic contaminant dilutes water carrying geogenic contaminants. This process is enabled by long well screens. Over-exploitation of aquifers in geothermal regions for agriculture can drive As concentrations in water from production wells to toxic levels even as the total dissolved solids remain low.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Arsênio/análise , Monitoramento Ambiental , México , Poluentes Químicos da Água/análise
5.
J Dairy Res ; 86(3): 303-306, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31328715

RESUMO

This research communication addresses the hypothesis that in dual-purpose goats, exposure to 1 h of extra-light given from 16 to 17 h after dawn (pulse of light) in winter stimulates milk yield. One group of goats was maintained under natural short photoperiod (natural day; ND (n = 7)). Another group of lactating females was submitted to an artificial long-day photoperiod consisting of 16 h light and 8 h darkness (long days; LD (n = 7)). A third group of females received one single hour of extra-light 16 h after the fixed dawn (pulse of light; PL (n = 6)). Goats from LD and PL yielded 30% more milk than goats from ND. Mean percentages of fat, protein and lactose contents in milk did not differ between the 3 groups at any stage of lactation, but these components in grams/day were higher in goats from PL than in the others two groups within the first 45 d of lactation. In conclusion, dual-purpose lactating goats that started their lactation during natural short days, the daily exposition to a 1-h pulse of light is sufficient to stimulate milk yield compared to females maintained under natural short photoperiod.


Assuntos
Cabras/fisiologia , Lactação/efeitos da radiação , Luz , Fotoperíodo , Animais , Clima , Gorduras/análise , Feminino , Lactação/fisiologia , Lactose/análise , México , Leite/química , Proteínas do Leite/análise , Estações do Ano
6.
Entropy (Basel) ; 21(7)2019 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-33267403

RESUMO

In this study, two empirical correlations of the Nusselt number, based on two artificial neural networks (ANN), were developed to determine the heat transfer coefficients for each section of a vertical helical double-pipe evaporator with water as the working fluid. Each ANN was obtained using an experimental database of 1109 values obtained from an evaporator coupled to an absorption heat transformer with energy recycling. The Nusselt number in the annular section was estimated based on the modified Wilson plot method solved by an ANN. This model included the Reynolds and Prandtl numbers as input variables and three neurons in their hidden layer. The Nusselt number in the inner section was estimated based on the Rohsenow equation, solved by an ANN. This ANN model included the numbers of the Prandtl and Jackob liquids as input variables and one neuron in their hidden layer. The coefficients of determination were R 2 > 0.99 for both models. Both ANN models satisfied the dimensionless condition of the Nusselt number. The Levenberg-Marquardt algorithm was chosen to determine the optimum values of the weights and biases. The transfer functions used for the learning process were the hyperbolic tangent sigmoid in the hidden layer and the linear function in the output layer. The Nusselt numbers, determined by the ANNs, proved adequate to predict the values of the heat transfer coefficients of a vertical helical double-pipe evaporator that considered biphasic flow with an accuracy of ±0.2 for the annular Nusselt and ±4 for the inner Nusselt.

7.
Arch. cardiol. Méx ; 88(4): 277-286, oct.-dic. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1124149

RESUMO

Resumen Antecedentes: Los procedimientos coronarios invasivos conllevan la administración de contraste y la exposición a radiaciones ionizantes, comportando un incremento de la morbimortalidad. La angiografía coronaria rotacional (ACR) permite adquirir múltiples proyecciones con una inyección de contraste. Hasta la fecha, no hay metaanálisis específicos comparando la ACR y la angiografía coronaria convencional (ACC) en pacientes en los que se realizan procedimientos coronarios invasivos, tanto diagnósticos como diagnósticos y terapéuticos. El objetivo de este metaanálisis es evaluar el impacto de la ACR en la cantidad de contraste, y la radiación ionizante en procedimientos coronarios invasivos. Métodos: Se realizó una búsqueda en las bases de datos PubMed y Ovid para identificar estudios tanto diagnósticos como diagnósticos y terapéuticos que comparasen ACR y ACC. Los estudios fueron evaluados sobre la calidad y los sesgos, y fueron incluidos si contemplaban alguna de las siguientes variables de valoración: volumen de contraste, radiación ionizante medida como producto dosis-área, Kerma-aire o tiempo de fluoroscopia. Resultados: Dieciséis estudios, totalizando 2,327 pacientes, fueron incluidos en el análisis final (1,146 pacientes recibieron ACR y 1,181, ACC), objetivándose diferencias significativas en volumen de contraste (diferencia estándar de medias (intervalo de confianza al 95%) −1.887 (−2.472 a −1.302); p < 0.001), producto dosis-área (−0.726 (−1.034 a −0.418); p < 0.001), Kerma-aire (−0.842 (−1.104 a −0.581); p < 0.001) y tiempo de fluoroscopia (0.263 (−0.496 a −0.030); p = 0.027). Conclusiones: La ACR permite reducir el volumen de contraste y la radiación, evaluada como producto dosis-área, Kerma-aire y tiempo de fluoroscopia en pacientes a los que se les realizan procedimientos coronarios invasivos.


Abstract Background: Invasive coronary procedures involve the administration of iodinated contrast and the exposure to ionising radiations, increasing morbidity and mortality. The rotational coronary angiography (RCA) allows acquiring multiple projections with a unique injection of iodinated contrast. To date, there are no meta-analyses specifically comparing RCA and conventional coronary angiography (CCA) in patients undergoing invasive coronary procedures, whether diagnostic or diagnostic and therapeutic. The aim of this meta-analysis is to assess the impact of RCA on the amount of iodinated contrast and the exposure to ionising radiations during invasive coronary procedures. Methods: A search in PubMed and Ovid databases was conducted to identify studies, including diagnostic and diagnostic and therapeutic studies, comparing RCA and CCA. The manuscripts were evaluated on quality and biases, and were included if they analysed any of the following endpoints: volume of contrast and exposure to ionising radiations measured as dose-area product, and Kerma-air or fluoroscopy time. Results: Sixteen studies, with a total of 2,327 patients, were included in the final analysis (1,146 patients underwent RCA and 1,181 patients underwent CCA), with significant differences being detected in volume of contrast (standard difference in means (95% confidence interval) −1.887 (−2.472 to −1.302); P < .001), dose-area product (−0.726 (−1.034 to −0.418); P < .001), Kerma-air (−0.842 (−1.104 to −0.581); P < .001), and fluoroscopy time (0.263 (−0.496 to −0.030); P = .027). Conclusions: RCA reduces the volume of contrast and the exposure to radiation, evaluated as dose-area product, Kerma-air, and fluoroscopy time, in patients undergoing invasive coronary procedures.


Assuntos
Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Angiografia Coronária/métodos , Meios de Contraste/administração & dosagem , Radiação Ionizante , Fluoroscopia , Compostos de Iodo/administração & dosagem
8.
Sci Total Environ ; 622-623: 1029-1045, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29890573

RESUMO

Fluoride (F), naturally found in aquifers around the world at toxic concentrations, causes disease in millions of people. The long-term stability, however, of those concentrations within intensively pumped aquifers is poorly characterized. We assessed long-term stability in the spatial distribution of F concentrations in an intensively pumped aquifer within the semi-arid, inter-montane Independence Basin in central Mexico between 1999 and 2016. Although stable in 16 re-sampled wells, F concentrations increased in some localities across the basin by as much as 4mg/L. Changes in recharge pathways to the deep aquifer were identified by analyzing changes in δ2H, δ18O and Cl/Br mass ratios. In 1999, δ2H and δ18O values suggested the aquifer was recharged in the mountains. In 2016, however, substantial increases in δ18O values in the center of the basin suggest recharge water is derived from rainfall that had experienced increased evaporation. In 1999, the mass ratio Cl/Br in groundwater was slightly enriched over local rainfall, and followed a single mixing line on a plot of Cl. vs. Cl/Br. In 2016, however, three distinct groupings of wells were evident, all following different mixing lines. These changes suggest input from new sources including urban sewage, evaporate dissolution, connate sea water and geothermal waters. Step-wise multiple regression was used to quantify the impact of physical and chemical parameters on F concentrations. In 1999, Li (6.8±1.7) and Na (0.01±0.004) drove F concentrations (R2=0.54). In 2016, Na (0.013±0.0018), HCO3 (0.004±0.001), Ca (-0.0018±0.00045), and Mg (-0.055±0.023) drove F concentrations (0.78). Irrigation pumping and urban expansion within semi-arid, groundwater-dependent, inter-montane basins drive mixing of disparate groundwater chemistries and introduces new sources of recharge to aquifers inducing changes in aquifer chemistry including increasing concentrations of geogenic toxic elements.


Assuntos
Recuperação e Remediação Ambiental/métodos , Fluoretos/análise , Água Subterrânea/química , Poluentes Químicos da Água/análise , México
9.
Nefrología (Madrid) ; 38(2): 169-178, mar.-abr. 2018. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-171085

RESUMO

Introducción y objetivos: La angiografía coronaria rotacional (ACR) permite reducir la cantidad de contraste administrado y puede prevenir el desarrollo de nefropatía inducida por contraste (NIC) durante los procedimientos coronarios invasivos. El objetivo del estudio es evaluar el impacto de la ACR en la aparición de NIC (aumento de creatinina ≥0,5mg/dL o ≥25%) tras un síndrome coronario agudo. Métodos: De abril a septiembre de 2016 se seleccionaron prospectivamente pacientes con síndrome coronario agudo remitidos para coronariografía diagnóstica con posibilidad de angioplastia ad hoc, que fueron estudiados con ACR o angiografía coronaria convencional (ACC) según criterio del operador. Se compararon la NIC (variable de valoración primaria), variables analíticas, angiográficas y clínicas. Resultados: De 235 pacientes reclutados, 116 pacientes fueron estudiados con ACR y 119 pacientes con ACC. El grupo de ACR presentaba mayor edad (64,0±11,8 vs. 59,7±12,1 años; p=0,006), más mujeres (44,8 vs. 17,6%; p<0,001) y peor filtrado glomerular estimado (76±25 vs. 86±27 mL/min/1,73 m2; p=0,001), con menos angioplastias (p<0,001). Asimismo, el grupo de ACR recibió menos contraste (113±92 vs. 169±103 mL; p<0,001), diferencias que se mantuvieron en los procedimientos diagnósticos (54±24 vs. 85±56 mL; p<0,001) y diagnóstico-terapéuticos (174±64 vs. 205±98 mL; p=0,049). El grupo de ACR presentó menos NIC (4,3 vs. 22,7%; p<0,001): en el análisis de regresión se objetivó que continuaba relacionándose con menor desarrollo de NIC (riesgo relativo ajustado: 0,868; IC 95%: 0,794-0,949; p=0,002). No hubo diferencias en las variables clínicas. Conclusiones: La ACR se asoció con menor administración de contraste durante procedimientos coronarios invasivos tras un síndrome coronario agudo, lo que resultó en una menor aparición de NIC (AU)


Introduction and objectives: Rotational coronary angiography (RCA) requires less contrast to be administered and can prevent the onset of contrast-induced nephropathy (CIN) during invasive coronary procedures. The aim of the study is to evaluate the impact of RCA on CIN (increase in serum creatinine ≥0.5mg/dl or ≥25%) after an acute coronary syndrome. Methods: From April to September 2016, patients suffering acute coronary syndromes who underwent diagnostic coronary angiography, with the possibility of ad hoc coronary angioplasty, were prospectively enrolled. At the operator's discretion, patients underwent RCA or conventional coronary angiography (CCA). CIN (primary endpoint), as well as analytical, angiographic and clinical endpoints, were compared between groups. Results: Of the 235 patients enrolled, 116 patients received RCA and 119 patients received CCA. The RCA group was composed of older patients (64.0±11.8 years vs. 59.7±12.1 years; p=0.006), a higher proportion of women (44.8 vs. 17.6%; p<0.001), patients with a lower estimated glomerular filtration rate (76±25 vs. 86±27ml/min/1.73 m2; p=0.001), and patients who underwent fewer coronary angioplasties (p<0.001) compared with the CCA group. Furthermore, the RCA group, received less contrast (113±92 vs. 169±103ml; p<0.001), including in diagnostic procedures (54±24 vs. 85±56ml; p<0.001) and diagnostic-therapeutic procedures (174±64 vs. 205±98ml; p=0.049) compared with the CCA group. The RCA group presented less CIN (4.3 vs. 22.7%; p<0.001) compared to the CCA group, and this finding was maintained in the regression analysis (Adjusted relative risk: 0.868; 95% CI: 0.794-0.949; p=0.002). There were no differences in clinical endpoints between the groups. Conclusions: RCA was associated with lower administration of contrast during invasive coronary procedures in acute coronary syndrome patients, resulting in lower incidence of CIN, in comparison with CCA (AU)


Assuntos
Humanos , Masculino , Feminino , Nefropatias/complicações , Angiografia Coronária/efeitos adversos , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/terapia , Angioplastia/métodos , Análise de Regressão , Estudos Prospectivos , Estudos de Coortes , 28599 , Tabagismo/complicações
10.
Nefrologia (Engl Ed) ; 38(2): 169-178, 2018.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28734584

RESUMO

INTRODUCTION AND OBJECTIVES: Rotational coronary angiography (RCA) requires less contrast to be administered and can prevent the onset of contrast-induced nephropathy (CIN) during invasive coronary procedures. The aim of the study is to evaluate the impact of RCA on CIN (increase in serum creatinine ≥0.5mg/dl or ≥25%) after an acute coronary syndrome. METHODS: From April to September 2016, patients suffering acute coronary syndromes who underwent diagnostic coronary angiography, with the possibility of ad hoc coronary angioplasty, were prospectively enrolled. At the operator's discretion, patients underwent RCA or conventional coronary angiography (CCA). CIN (primary endpoint), as well as analytical, angiographic and clinical endpoints, were compared between groups. RESULTS: Of the 235 patients enrolled, 116 patients received RCA and 119 patients received CCA. The RCA group was composed of older patients (64.0±11.8 years vs. 59.7±12.1 years; p=0.006), a higher proportion of women (44.8 vs. 17.6%; p<0.001), patients with a lower estimated glomerular filtration rate (76±25 vs. 86±27ml/min/1.73 m2; p=0.001), and patients who underwent fewer coronary angioplasties (p<0.001) compared with the CCA group. Furthermore, the RCA group, received less contrast (113±92 vs. 169±103ml; p<0.001), including in diagnostic procedures (54±24 vs. 85±56ml; p<0.001) and diagnostic-therapeutic procedures (174±64 vs. 205±98ml; p=0.049) compared with the CCA group. The RCA group presented less CIN (4.3 vs. 22.7%; p<0.001) compared to the CCA group, and this finding was maintained in the regression analysis (Adjusted relative risk: 0.868; 95% CI: 0.794-0.949; p=0.002). There were no differences in clinical endpoints between the groups. CONCLUSIONS: RCA was associated with lower administration of contrast during invasive coronary procedures in acute coronary syndrome patients, resulting in lower incidence of CIN, in comparison with CCA.


Assuntos
Síndrome Coronariana Aguda/diagnóstico por imagem , Meios de Contraste/efeitos adversos , Angiografia Coronária/métodos , Iopamidol/análogos & derivados , Nefropatias/induzido quimicamente , Síndrome Coronariana Aguda/epidemiologia , Síndrome Coronariana Aguda/terapia , Idoso , Fármacos Cardiovasculares/uso terapêutico , Comorbidade , Dislipidemias/epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Incidência , Iopamidol/efeitos adversos , Nefropatias/epidemiologia , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea , Estudos Prospectivos , Fumar/epidemiologia
11.
Arch Cardiol Mex ; 88(4): 277-286, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-28888725

RESUMO

BACKGROUND: Invasive coronary procedures involve the administration of iodinated contrast and the exposure to ionising radiations, increasing morbidity and mortality. The rotational coronary angiography (RCA) allows acquiring multiple projections with a unique injection of iodinated contrast. To date, there are no meta-analyses specifically comparing RCA and conventional coronary angiography (CCA) in patients undergoing invasive coronary procedures, whether diagnostic or diagnostic and therapeutic. The aim of this meta-analysis is to assess the impact of RCA on the amount of iodinated contrast and the exposure to ionising radiations during invasive coronary procedures. METHODS: A search in PubMed and Ovid databases was conducted to identify studies, including diagnostic and diagnostic and therapeutic studies, comparing RCA and CCA. The manuscripts were evaluated on quality and biases, and were included if they analysed any of the following endpoints: volume of contrast and exposure to ionising radiations measured as dose-area product, and Kerma-air or fluoroscopy time. RESULTS: Sixteen studies, with a total of 2,327 patients, were included in the final analysis (1,146 patients underwent RCA and 1,181 patients underwent CCA), with significant differences being detected in volume of contrast (standard difference in means [95% confidence interval] -1.887 [-2.472 to -1.302]; P<.001), dose-area product (-0.726 [-1.034 to -0.418]; P<.001), Kerma-air (-0.842 [-1.104 to -0.581]; P<.001), and fluoroscopy time (0.263 [-0.496 to -0.030]; P=.027). CONCLUSIONS: RCA reduces the volume of contrast and the exposure to radiation, evaluated as dose-area product, Kerma-air, and fluoroscopy time, in patients undergoing invasive coronary procedures.


Assuntos
Meios de Contraste/administração & dosagem , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Fluoroscopia , Humanos , Compostos de Iodo/administração & dosagem , Radiação Ionizante
12.
Anim Sci J ; 87(4): 484-91, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26261065

RESUMO

This study was designed to determine whether any relationship exists between exposure to artificial long days, milk yield, maternal plasma insulin-like growth factor 1 (IGF-1) levels, and kid growth rate in goats. One group of lactating goats was maintained under naturally decreasing day length (control group; n = 19), while in another one, they were kept under artificial long days (LD group; n = 19). Milk yield was higher in goats from the LD group than that in the control group (P < 0.05). Maternal IGF-1 levels at day 57 of lactation were higher (P < 0.05) in goats from the LD group than the levels in the control group and were positively correlated with the total milk yields per goat at days 43 and 57 of lactation (r = 0.77 and r = 0.84, respectively; P < 0.01). Daily weight gain at week 4 was higher (P < 0.01) in kids from the LD group than that in kids from the control group and was correlated with total and average IGF-1 maternal levels (r = 0.60 and r = 0.60, P < 0.05). It was concluded that submitting lactating goats to artificial long days increases milk yield, plasma IGF-1 maternal levels and the growth rate of the kids.


Assuntos
Ritmo Circadiano/fisiologia , Cabras/crescimento & desenvolvimento , Cabras/fisiologia , Fator de Crescimento Insulin-Like I/metabolismo , Lactação/fisiologia , Fotoperíodo , Animais , Feminino , Masculino , Aumento de Peso
14.
Theriogenology ; 84(6): 880-6, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26117287

RESUMO

In seasonally anovulatory goats, daily contact with photostimulated bucks for 15 days stimulates ovulations in most females. In this study, we determined whether ovulation could be induced in goats exposed to photostimulated bucks for less than 15 days. Bucks were rendered sexually active during the nonbreeding season by exposure to 2.5 months of long days from November 1. The control group of females was exposed to one photostimulated buck for 15 days (n = 12). Other three experimental groups were exposed to males (n = 1 per group) for 1, 5, or 10 days (n = 14 or 15 females per group). Ovulations were determined by measurement of daily plasma progesterone concentrations during 17 days. All females from the control and experimental groups ovulated at least once during the experiment (P > 0.05). Furthermore, the proportions of goats that displayed a short luteal phase followed by a new ovulation, or a normal luteal phase after being in contact with males, did not differ between groups depending on the duration of time of contact with the photostimulated males (P > 0.05). In contrast, the proportions of females that displayed a short luteal phase followed by anovulation were greater in goats in contact with males for 1 day than in those in contact with males for 10 and 15 days (P < 0.05), whereas they did not differ from females exposed to males for 5 days (P > 0.05). We conclude that 1 day of contact with sexually active males is long enough to stimulate the ovulatory activity in seasonally anovulatory goats. However, a significantly higher proportion of females exposed to males for 1 day did not ovulate again after showing a short luteal phase.


Assuntos
Anestro/fisiologia , Cabras/fisiologia , Indução da Ovulação/veterinária , Comportamento Sexual Animal , Animais , Feminino , Fase Luteal , Masculino , Ovulação/fisiologia , Indução da Ovulação/métodos , Progesterona/sangue , Reprodução/fisiologia , Reprodução/efeitos da radiação , Estações do Ano , Fatores de Tempo
16.
Open Cardiovasc Med J ; 8: 61-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25152777

RESUMO

BACKGROUND: To describe the characteristics of patients ≤40 years of age hospitalized for acute coronary syndrome, analyze the risk factors and identify the variables associated with prognosis. METHODS: Case series of patients admitted between 2003 and 2012 inclusive in a tertiary hospital (123 consecutive cases admitted between 2003 and 2012), and case-control study (369 controls selected from the general population matched for sex and age with cases, at a ratio of 3:1). OUTCOME VARIABLES: Mortality, likelihood of survival without readmission for heart-related problems, extent of coronary disease as determined by coronary angiography and cardiovascular risk factors. RESULTS: Mean age was 35.4±4.8 years and 83.7% of the participants were men. Myocardial infarction with abnormal Q wave (48%) and single-vessel involvement (44.7%) predominated. Intrahospital mortality was 1.6%. For the 108 patients eventually included in the follow-up, likelihood of readmission-free survival after 60 months was 69.3±4.8%. In the case group 36% of the patients admitted to using cocaine. Compared to controls, the prevalence in patients was higher for smoking (74.8 vs 33.1%, p<0001), diabetes (14.6% vs 5.1%, p=0.001), low HDL-cholesterol (82.9 vs 34.1%, p<0.001) and obesity (30.0 vs 20.3%, p=0.029). Decreased left ventricular ejection fraction (odds ratio=2.2, p=0.033) and smoking (odds ratio=7.8, p=0.045) were associated with readmission for coronary syndrome. CONCLUSION: Acute coronary syndrome in people younger than 40 years is associated with diabetes and unhealthy lifestyle: smoking, sedentary behavior (low HDL-cholesterol), cocaine use and obesity. The readmission rate is high, and readmission is associated with smoking and decreased ejection fraction.

17.
Heart ; 100(1): 34-40, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24165855

RESUMO

OBJECTIVE: Klotho is involved in vascular health. We aimed to analyse in a cross-sectional study the relationship between Klotho and human coronary artery disease (CAD). METHODS: The study included 371 subjects who underwent coronary angiography and 70 patients who underwent elective cardiac surgery recruited between May 2008 and June 2009. The presence and severity (stenosis index) of CAD, cardiovascular risk factors, Klotho gene expression in the thoracic aorta, and serum soluble Klotho concentrations were evaluated. RESULTS: The soluble Klotho concentration was lower (p<0.001) in patients with significant CAD (n=233). The maximal stenosis observed in every epicardial artery and the stenosis severity index was significantly lower in patients within the higher soluble Klotho concentrations (p<0.0001). Multiple regression analysis showed that serum Klotho concentrations were inverse and significantly associated with CAD (adjusted R(2)=0.67, p<0.001). Multivariate logistic regression analysis showed that risk factors for significant CAD included age, diabetes, smoking and inflammation, whereas high serum Klotho values were associated with a lower risk for CAD. Lower mRNA expression level of Klotho was observed in 46 patients with significant CAD, as compared with subjects without CAD (p=0.01). Logistic regression analysis showed that high Klotho gene expression was independently associated with lower risk for CAD. CONCLUSIONS: Patients with significant CAD present lower soluble concentrations of Klotho, as well as reduced levels of Klotho gene expression in the vascular wall. Reduced serum Klotho concentrations and decreased vascular Klotho gene expression were associated with the presence and severity of CAD independently of established cardiovascular risk factors.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/metabolismo , Vasos Coronários/metabolismo , Glucuronidase/metabolismo , Idoso , Envelhecimento , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Feminino , Regulação da Expressão Gênica , Glucuronidase/genética , Humanos , Proteínas Klotho , Masculino , Pessoa de Meia-Idade , Revascularização Miocárdica , RNA/genética , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Índice de Gravidade de Doença
18.
Horm Behav ; 62(4): 525-30, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22974758

RESUMO

We investigated whether live vocalizations emitted by bucks interacting with anestrous females stimulate secretion of LH, estrous behavior and ovulation in anestrous goats. In experiment 1, bucks rendered sexually active by exposure to long days followed by natural photoperiod were exposed in a light-proof-building to five anestrous females. Buck vocalizations were reproduced through a microphone-amplifier-loudspeaker system to an open pen where one group of goats (n=6) was exposed for 10 days to these live vocalizations. Another group of females (n=6) was isolated from males and vocalizations. The proportion of goats displaying estrous behavior was significantly higher in females exposed to buck vocalizations than in females isolated from males. The proportion of goats that ovulated did not differ between the 2 groups (exposed to males versus isolated). In experiment 2, female goats that either had previous contact with males (n=7), or no previous contact with males (n=7) were exposed to live buck vocalizations, reproduced as described in experiment 1, for 5 days. The number and amplitude of LH pulses did not differ between groups before exposition to buck vocalizations. Five days of exposure to male vocalizations significantly increased LH pulsatility only in females that had previous contact with males, while LH pulse amplitude was not modified. We concluded that live buck vocalizations can stimulate estrous behavior and LH secretion in goats if they have had previous contact with bucks.


Assuntos
Anestro , Ciclo Estral/metabolismo , Ciclo Estral/fisiologia , Cabras , Hormônio Luteinizante/metabolismo , Vocalização Animal/fisiologia , Anestro/sangue , Anestro/metabolismo , Anestro/fisiologia , Animais , Cruzamento , Corte , Feminino , Cabras/sangue , Cabras/metabolismo , Cabras/fisiologia , Abrigo para Animais , Hormônio Luteinizante/sangue , Masculino , Estações do Ano , Comportamento Sexual Animal/fisiologia
19.
Horm Behav ; 60(5): 484-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21821035

RESUMO

We investigated whether LH secretion, estrous behavior and fertility would differ between sexually inexperienced and experienced anestrous goats exposed to the males. Male goats were rendered sexually active during the reproductive rest season by exposure to 2.5 months of artificial long days. Two groups of anovulatory sexually inexperienced and sexually experienced does were exposed to males during 15 days (n = 20 per group). LH pulsatility was determined every 15 min from 4h before to 8h after introducing males (Day 0). Estrous behavior was recorded twice daily. Pregnancy rates were determined on Day 50. Fertility was determined at parturition. Male sexual behavior was registered on days 1 and 2 during 1h. Before introducing the males, the number of LH pulses did not differ between groups. After introduction of the males, all females increased their LH pulsatility, but the number of pulses did not differ between sexually inexperienced and experienced goats. The proportion of females displaying estrous behavior with a high pregnancy rate and fertility did not differ between inexperienced and experienced goats. The sexual behavior of the males did not differ significantly between those interacting with sexually inexperienced or experienced goats. We conclude that goats can show substantial endocrine and reproductive responses to males, even in the absence of previous sexual experience, when sexually active bucks are used.


Assuntos
Anestro/fisiologia , Estro/fisiologia , Fertilidade/fisiologia , Cabras/fisiologia , Hormônio Luteinizante/sangue , Comportamento Sexual Animal/fisiologia , Animais , Feminino , Masculino , Fotoperíodo , Gravidez , Taxa de Gravidez
20.
Horm Behav ; 52(1): 99-105, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17482617

RESUMO

Maternal behavior in the goat appears at the time of parturition, partly under the activating influence of vaginocervical stimulation. Mothers actively lick their neonate and rapidly establish a selective bond with their kid through olfactory recognition. They also develop visual and acoustic recognition of the kid within 4 h following birth. Acoustic recognition is present at 48 h. The establishment of maternal recognition can be impaired by underfeeding during the second half of pregnancy. There is no indication that the mechanisms controlling the onset of maternal behavior and bonding are different from those reported in sheep, despite the fact that lambs start to follow their mother within a few hours after birth and kids hide for about a week. During lactation, the cues provided by the kid are necessary for the maintenance of maternal responsiveness, but suckling itself does not appear of primary importance. The presence of the kid also modulates the hormonal response to udder stimulation and influences recovery of postpartum sexual activity when kidding (i.e. birthing) takes place in autumn. Finally, the rapid establishment of mutual attachment between mother goats (does) and their kids offers the possibility to investigate an aspect of mother-young affiliation that is not present in many laboratory species.


Assuntos
Cabras/psicologia , Comportamento Materno/fisiologia , Animais , Feminino , Cabras/fisiologia , Lactação/fisiologia , Apego ao Objeto , Período Pós-Parto/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...