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1.
Appl Ergon ; 70: 142-147, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29866304

RESUMEN

Poor sleep negatively impacts vigilance and is associated with reduced well-being and work productivity. While many individuals depend on caffeine to counteract the cognitive consequences of poor sleep and restore optimal work performance, few studies have naturalistically evaluated this strategy. This study examined the effects of coffee on vigilance, comparing individuals based on recent sleep quality. Sixty-nine participants completed two randomized, counterbalanced trials consisting of 237 ml water or coffee (100 mg caffeine), followed by a continuous performance test assessing vigilance at 30, 90, and 120 min. While coffee improved and stabilized reaction time at all three assessments regardless of recent sleep history, its effects on omission and commission errors were seen only at 90 min; coffee increased commission errors and only partially reduced omission errors in individuals reporting poor sleep quality. The use of coffee to combat poor sleep may therefore be detrimental in situations requiring inhibitory control.


Asunto(s)
Nivel de Alerta/efectos de los fármacos , Cafeína/farmacología , Estimulantes del Sistema Nervioso Central/farmacología , Café , Cognición/efectos de los fármacos , Sueño , Adolescente , Eficiencia/efectos de los fármacos , Humanos , Tiempo de Reacción/efectos de los fármacos , Privación de Sueño/fisiopatología , Privación de Sueño/psicología , Encuestas y Cuestionarios , Análisis y Desempeño de Tareas , Lugar de Trabajo , Adulto Joven
2.
Theriogenology ; 78(1): 12-27, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22464816

RESUMEN

Supplementary fat positively influences reproductive performance in dairy cattle, although the mechanisms involved are not clearly defined. Our objective was to determine the effects of four different fat supplements on follicle development, plasma steroid hormone concentrations and prostaglandin (PG) synthesis in lactating dairy cattle. Forty-eight early lactation Holstein-Friesian cows (21 primiparous, 27 multiparous) were used in a completely randomized block design. Cows were fed the same basal TMR diet and received one of four fat supplements: (i) palmitic acid (18:0 fatty acid; Control), (ii) flaxseed (rich in 18:3 n-3 fatty acid; Flax), (iii) conjugated linoleic acid (a mixture of cis-9, trans-11 and trans-10, cis-12 isomers; CLA), and (iv) fish oil (rich in 20:5 and 22:6 n-3 fatty acids; FO). All lipid supplements were formulated to be isolipidic; palmitic acid was added as necessary to provide a total lipid supplement intake of 500 g/day. Cows were synchronized to be in estrus on Day 15 of dietary treatment. All antral follicles were counted, and dominant follicles, subordinate follicles and corpora lutea were measured daily via transrectal ovarian ultrasonography for one complete estrous cycle. Blood samples were collected daily, and selected samples were analyzed for progesterone, estradiol, insulin-like growth factor-1, insulin, cholesterol and non-esterified fatty acids. Estrus was synchronized a second time, and liver and endometrial biopsies were collected on Day 7 of the estrous cycle. Gene expression was evaluated for a number of genes involved in prostaglandin synthesis (endometrium) and fatty acid uptake and utilization (liver). Fat supplementation had little effect on follicle development. Cows receiving supplementary n-3 fatty acids had lesser plasma progesterone (P4) and smaller corpora lutea than cows receiving the CLA or Control supplements. Effects of fat supplementation on the endometrial expression of genes involved in PG synthesis were minor. Hepatic expression of SREBF1, ASCL1 and FABP1 was reduced by FO supplementation. Reduced plasma P4 in n-3 supplemented cows may lead to a suboptimal uterine environment for embryo development and hence reduced fertility compared to cows receiving the control or CLA supplements.


Asunto(s)
Bovinos , Grasas de la Dieta/farmacología , Suplementos Dietéticos , Lactancia/efectos de los fármacos , Reproducción/efectos de los fármacos , Alimentación Animal/provisión & distribución , Animales , Bovinos/sangre , Bovinos/genética , Bovinos/metabolismo , Industria Lechera , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/provisión & distribución , Suplementos Dietéticos/estadística & datos numéricos , Eficiencia/efectos de los fármacos , Ácidos Grasos Insaturados/administración & dosificación , Ácidos Grasos Insaturados/farmacología , Femenino , Lactancia/genética , Lactancia/fisiología , Ácidos Linoleicos Conjugados/administración & dosificación , Ácidos Linoleicos Conjugados/farmacología , Aceite de Linaza/administración & dosificación , Aceite de Linaza/farmacología , Leche/metabolismo , Ovulación/sangre , Ovulación/efectos de los fármacos , Ovulación/genética , Ovulación/metabolismo , Reproducción/genética , Reproducción/fisiología
3.
J Drugs Dermatol ; 10(2): 189-96, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21283925

RESUMEN

Plaque psoriasis is a chronic, inflammatory skin disease that can be difficult to treat. Traditional systemic agents, topical agents, phototherapy and biologic therapies can be used for patients with psoriasis. The authors reviewed published results from a variety of sources in order to better understand the effects of psoriasis treatments on patient satisfaction, patient adherence, healthcare resource utilization and productivity. Patients with psoriasis consider many factors when evaluating therapies, including the time for the therapy to be effective, cosmetic issues common with topical therapies and travel to and from phototherapy centers. Satisfaction with and adherence to biologic therapies appears to be greater than for traditional therapies. Although biologic therapies are generally more expensive than are traditional, these agents may contribute to decreased healthcare utilization and increased productivity.


Asunto(s)
Productos Biológicos/uso terapéutico , Terapia Biológica , Eficiencia/efectos de los fármacos , Recursos en Salud/estadística & datos numéricos , Terapia PUVA , Psoriasis/tratamiento farmacológico , Psoriasis/terapia , Enfermedad Crónica , Ensayos Clínicos como Asunto , Humanos , Cooperación del Paciente , Satisfacción del Paciente , Psoriasis/epidemiología
4.
Theriogenology ; 70(6): 992-1003, 2008 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-18692227

RESUMEN

The objective of this study was to examine the effects of dietary n-3 polyunsaturated fatty acid (n-3 PUFA) supplementation on embryo yield and quality in heifers. Animals were individually offered barley straw and concentrate diets supplemented with either palmitic acid (C16:0; CON) or a partially rumen protected n-3 PUFA-enriched supplement. Following oestrous cycle synchronisation, superovulation was induced using FSH. Blood samples were collected for the measurement of fatty acids, metabolites, insulin and IGF-1. On day 7 post-insemination the number of ovulations was estimated and embryos recovered non-surgically and quality graded. At embryo recovery 50 ml of the uterine flushing was collected from each horn for fatty acid analysis. Grade 1 embryos were isolated, snap frozen in liquid nitrogen and stored at -80 degrees C. mRNA expression for six genes, LIF, BAX, Cx43 and E-CAD associated with embryo development, and PPAR-alpha and -delta, associated with lipid metabolism was analysed. The n-3 PUFA supplementation increased plasma n-3 PUFA concentration (P<0.05) and reduced n-6:n-3 PUFA ratio (P<0.05). Uterine concentration of the n-3 PUFA, eicosapentaenoic acid was increased (P<0.05) and the concentration of arachidonic acid decreased (P<0.05) following n-3 PUFA supplementation. While CON increased triglyceride concentrations, diet did not affect the other plasma metabolites, insulin or IGF-1 (P>0.05). Similarly, there was no effect of diet on superovulation rate, embryo recovery rate, embryo quality (P>0.05) or mRNA expression of the genes examined (P>0.05).


Asunto(s)
Bovinos/fisiología , Suplementos Dietéticos , Eficiencia/efectos de los fármacos , Embrión de Mamíferos/citología , Embrión de Mamíferos/efectos de los fármacos , Ácidos Grasos Omega-3/farmacología , Animales , Bovinos/sangre , Bovinos/embriología , Embrión de Mamíferos/metabolismo , Sincronización del Estro/sangre , Sincronización del Estro/métodos , Ácidos Grasos/sangre , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Control de Calidad , Superovulación/sangre , Superovulación/efectos de los fármacos , Irrigación Terapéutica , Útero/química , Útero/efectos de los fármacos
5.
Domest Anim Endocrinol ; 35(1): 35-45, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18308502

RESUMEN

The effects of specific nutrients on secretion and plasma concentrations of gut peptides (glucagon-like peptide-1((7-36)) amide (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and cholecystokinin-8 (CCK)) differ across species, but are not reported for cattle. Our objective was to determine acute (hours) and chronic (1 week) effects of increased abomasal supply of protein, carbohydrate, or fat to the small intestine on dry matter intake (DMI) and plasma concentrations of GLP-1, GIP, CCK, and insulin. Four mid-lactation Holstein cows were used in a 4 x 4 Latin square design experiment. Treatments were 7-day abomasal infusions of water, soybean oil (500 g/d), corn starch (1100 g/d), or casein (800 g/d). Jugular vein plasma was obtained over 7h at the end of the first and last day of infusions. Oil infusion decreased DMI on day 7, but total metabolizable energy (ME) supply (diet plus infusate) did not differ from water infusion. Casein and starch infusion had no effect on feed DMI; thus, ME supply increased. Decreased DMI on day 7 of oil infusion was accompanied by increased plasma GLP-1 concentration, but decreased plasma CCK concentration. Increased plasma GIP concentration was associated with increased ME supply on day 7 of casein and starch infusion. Casein infusion tended to increase plasma CCK concentration on both days of sampling, and increased plasma GLP-1 and insulin concentration on day 1 of infusion. The present data indicate a sustained elevation of plasma concentration of GLP-1, but not CCK, may contribute to the reduced DMI observed in dairy cows provided supplemental fat.


Asunto(s)
Abomaso , Caseínas/administración & dosificación , Bovinos , Ingestión de Alimentos/efectos de los fármacos , Hormonas Gastrointestinales/sangre , Lactancia/sangre , Abomaso/efectos de los fármacos , Alimentación Animal , Animales , Caseínas/farmacología , Bovinos/sangre , Industria Lechera , Esquema de Medicación , Eficiencia/efectos de los fármacos , Ingestión de Energía/efectos de los fármacos , Femenino , Infusiones Parenterales , Leche/química , Hormonas Peptídicas/sangre , Aceite de Soja , Almidón , Factores de Tiempo
6.
Anim Reprod Sci ; 106(3-4): 221-31, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17513073

RESUMEN

We determined whether source of trace mineral supplementation prior to embryo collection affected embryo production and quality. Angus half-sibling heifers (n=20) originating from a common herd were assigned to three treatment groups using a 3 x 3 latin square design replicated in time (3 x) and space (6 x complete and 1x incomplete): (1) heifers received no added mineral to their diet (control; n=53); (2) heifers received a commercially available organic mineral supplement (organic; n=52); or (3) heifers received an all inorganic mineral supplement (inorganic; n=55). All heifers had ad libitum access to hay and were fed a supplement containing corn and soybean meal. Treatments were initiated 23 days prior to embryo recovery. Heifers were given a 45-day adaptation period of no mineral supplementation before initiating a new treatment. Ovarian structures were evaluated using transrectal ultrasonography to determine the presence and number of follicles and CL on each ovary. The mean number of recovered ova/embryos was similar among treatments (4.1+/-0.7, 3.8+/-0.7, and 3.3+/-0.7 for control, inorganic, and organic treatments, respectively), the number of unfertilized oocytes was greater (P<0.05) for inorganic (2.3+/-0.5) and control (1.6+/-0.5) treated heifers than organic (0.4+/-0.4) treated heifers. No differences among treatments existed for the number of degenerate or transferable embryos, but individual heifer influenced the total number of embryos/ova, unfertilized ova, and transferable embryos recovered. We conclude that heifer accounted for the greatest differences in embryo production and quality. Source of trace mineral supplementation did not significantly alter embryo number or quality in superovulated purebred Angus heifers fed a well-balanced diet, meeting all trace mineral requirements.


Asunto(s)
Suplementos Dietéticos , Fase Folicular/efectos de los fármacos , Ovulación/efectos de los fármacos , Superovulación/efectos de los fármacos , Oligoelementos/farmacología , Alimentación Animal , Animales , Bovinos , Recuento de Células , Eficiencia/efectos de los fármacos , Transferencia de Embrión , Embrión de Mamíferos , Femenino , Hormona Folículo Estimulante/farmacología , Fase Folicular/fisiología , Recuperación del Oocito , Oocitos/citología , Oocitos/efectos de los fármacos , Embarazo , Control de Calidad , Oligoelementos/química
7.
Theriogenology ; 65(2): 275-87, 2006 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-15979699

RESUMEN

The purpose of this study was to evaluate whether enriching the oocyte in vitro maturation medium with cystine, in the presence of cysteamine, would improve the in vitro embryo production efficiency in buffalo by further increasing the GSH reservoir created by the oocyte during maturation. Cumulus-oocytes complexes were matured in vitro in TCM 199 + 10% FCS, 0.5 microg/ml FSH, 5 microg/ml LH and 1 microg/ml 17beta-estradiol in the absence or presence of cysteamine (50 microM), with or without 0.3mM cystine. In Experiment 1, glutathione content was measured by high-performance liquid chromatography and fluorimetric analysis in representative samples of oocytes matured in the four different experimental conditions. In Experiment 2, oocytes were fixed and stained to assess nuclear maturation and normal pronuclear development following IVM and IVF respectively. In Experiment 3, mature oocytes were in vitro fertilized and cultured to assess development to blastocysts. In all supplemented groups the intracytoplasmic GSH concentration was significantly higher than the control, with the highest GSH levels in oocytes matured in the presence of both thiol compounds (3.6, 4.7, 5.4 and 6.9 picomol/oocyte in the control, cysteamine, cystine and cystine+cysteamine groups, respectively; P < 0.05). Cystine supplementation of IVM medium, both in the presence or absence of cysteamine, significantly increased the proportion of oocytes showing two normal synchronous pronuclei following fertilization. In all supplemented groups, cleavage rate was significantly improved compared to the control (55, 66.1, 73.5 and 78.4% in the control, cysteamine, cystine and cystine+cysteamine groups, respectively; P < 0.05). Similarly, blastocyst yield was also increased in the three enriched groups compared to the control (17.1, 23.8, 29.3, 30.9% in the control, cysteamine, cystine and cystine+cysteamine groups, respectively; P < 0.05). Overall, the addition of cystine to a cysteamine-enriched medium resulted in a significant increase of cleavage rate and transferable embryo yield compared to the medium supplemented with only cysteamine.


Asunto(s)
Búfalos/embriología , Cistina/farmacología , Desarrollo Embrionario/efectos de los fármacos , Glutatión/biosíntesis , Glutatión/efectos de los fármacos , Animales , Búfalos/crecimiento & desarrollo , Núcleo Celular/efectos de los fármacos , Fase de Segmentación del Huevo/efectos de los fármacos , Medios de Cultivo/química , Cisteamina/farmacología , Eficiencia/efectos de los fármacos , Femenino , Fertilización/efectos de los fármacos , Fertilización In Vitro/métodos , Glutatión/análisis , Masculino
8.
Rocz Panstw Zakl Hig ; 56(1): 57-65, 2005.
Artículo en Polaco | MEDLINE | ID: mdl-16080445

RESUMEN

The presented research project involved investigations aiming at assessing, on the basis of the consumption anamnesis from the last 24 hours, the method of nutrition concerning the supply with vitamin C and E, the state of saturation of the organisms with these vitamins by determining their concentrations in the blood serum employing the high performance liquid chromatography (HPLC) method and, on the basis of the step test (according to Mazur and co-workers), the physical efficiency of young persons practicing various sports of the endurance--high-speed nature such as swimming, canoeing and rowing. Investigations were carried out in two 30-person groups of which one ate food supplemented with C and E vitamins, whereas the other one obtained plain, unsupplemented food. In the course of the performed experiments, it was found that young sportsmen were nourished properly and adequately to the sports disciplines they practiced. It also referred to the supply in vitamins C and E. The state of the saturation of their organisms with these vitamins was optimal as evidenced by their concentrations in the blood serum and their physical efficiency was quite satisfactory. The performed statistical analysis showed a significant correlation between the nutrition of sportsmen supplemented with vitamin C in the form of kiwi fruits and vitamin E in capsules and their physical efficiency.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/sangre , Resistencia Física/efectos de los fármacos , Deportes , Vitamina E/administración & dosificación , Vitamina E/sangre , Adolescente , Antioxidantes/administración & dosificación , Antioxidantes/metabolismo , Cromatografía Líquida de Alta Presión , Eficiencia/efectos de los fármacos , Frutas , Humanos , Masculino , Resultado del Tratamiento
9.
Int J Vitam Nutr Res Suppl ; 30: 163-91, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2507696

RESUMEN

Vitamins serve primarily as regulators of metabolic functions, many of which are critical to exercise performance. Depending upon the nature of their sport, e.g., strength, speed, power, endurance, or fine motor control, athletes may use megadoses of various vitamins in attempts to increase specific metabolic processes important to improved performance. Surveys have indicated that most elite athletes do take vitamin supplements, often in dosages greater than 50-100 times the United States Recommended Dietary Allowances. The theoretical basis underlying the use of each vitamin depends upon its specific metabolic function in relation to sport. Vitamin A functions to maintain night vision; thiamin, riboflavin, niacin, and pantothenic acid are all involved in muscle cell energy metabolism; niacin may also block free fatty acid release; pyridoxine is involved in the synthesis of hemoglobin and other oxygen transfer protein; folic acid and vitamin B12 are integrally involved in red blood cell (RBC) development; vitamins C and E are antioxidants, possibly preventing the destruction of the red blood cell membrane during exercise; vitamin D may be involved in muscle cell energetics through its influence on calcium. These are but a few of the possible metabolic functions of vitamins which have been suggested to have ergogenic applications to sport. Research has shown that a vitamin deficiency impairs physical performance. If this deficiency is corrected, performance usually improves. In general, vitamin supplementation to an athlete on a well-balanced diet has not been shown to improve performance. However, additional research with certain vitamins appears to be warranted, such as with the vitamin B complex and fine motor control, and with vitamin E and endurance at high altitudes. Moreover, research with megadose supplementation may also be necessary.


Asunto(s)
Deportes , Vitaminas/farmacología , Eficiencia/efectos de los fármacos , Humanos , Resistencia Física/efectos de los fármacos , Vitaminas/administración & dosificación
10.
Kardiologiia ; 28(1): 14-7, 1988 Jan.
Artículo en Ruso | MEDLINE | ID: mdl-3357291

RESUMEN

Acute nifedipine tests and courses of nifedipine treatment were conducted in 30 patients with essential hypertension. The response of arterial blood pressure and cerebral hemodynamics to the acute test coincided with the results of a treatment course. The hypotensive effect, associated with nifedipine treatment, is combined with favorable cerebral hemodynamic changes and an increase in mental performance of hypertensive patients. Nifedipine treatment as an independent therapy is primarily indicated to patients showing spastic rheoencephalographic changes.


Asunto(s)
Circulación Cerebrovascular/efectos de los fármacos , Eficiencia/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Procesos Mentales/efectos de los fármacos , Nifedipino/uso terapéutico , Adolescente , Adulto , Enfermedad Coronaria/tratamiento farmacológico , Enfermedad Coronaria/fisiopatología , Enfermedad Coronaria/psicología , Femenino , Hemodinámica/efectos de los fármacos , Humanos , Hipertensión/fisiopatología , Hipertensión/psicología , Masculino , Persona de Mediana Edad , Psicofisiología
11.
J Occup Med ; 23(10): 699-704, 1981 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7299507

RESUMEN

This study was conducted to examine the relationship between anemia, supplementation with iron and vitamin C, and productivity. Using the cyanmethemoglobin method, 671 female garment factory workers were examined. On the basis of the World Health Organization (WHO) standard, 98 were found to be mildly or moderately/severely anemic. An equal number was randomly chosen from the nonanemic workers. The subjects were then randomly assigned to either the placebo group or the group receiving 525 mg of ferrous sulfate (105 mg elemental iron) and 500 mg ascorbic acid. Only 118 of the 196 subjects completed the three-month study. The mean hemoglobin (Hb) and work output, as indicated by efficiency rating (ER), of the placebo group did not change significantly. Mildly anemic workers with supplements showed a significant improvement in mean Hb, but not in mean ER. The moderately/severely anemic group receiving supplements had significant increases in both Hb and ER.


Asunto(s)
Anemia/sangre , Ácido Ascórbico/farmacología , Eficiencia/efectos de los fármacos , Empleo , Hemoglobinas , Hierro/farmacología , Adolescente , Adulto , Anemia/tratamiento farmacológico , Ácido Ascórbico/uso terapéutico , Femenino , Humanos , Hierro/uso terapéutico
12.
Br Med J ; 2(6204): 1546-9, 1979 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-534861

RESUMEN

The effects of iron-deficiency anaemia on workers productivity were studied in a tea plantation in Sri Lanka. The quantity of tea picked per day was studied before and after iron supplementation or placebo treatment. After one month's treatment significantly more tea was picked when the haemoglobin (Hb) concentration was increased by iron supplementation than when it was not. The degree of improvement was greater in more-anaemic subjects (those with concentrations of 6.0-9.0 g Hb/dl). The level of physical activity of anaemic subjects in their everyday environment was also recorded for four or 24 hours continuously both before and after treatment. After three weeks these levels was significantly greater in the iron-treated than matched placebo-treated subjects. The economic implications of increased work productively with iron treatment are evident, particularly in developing countries. These results also provide strong evidence for the clinical impression that people with iron-deficiency anaemia suffer from tiredness and weakness.


Asunto(s)
Anemia Hipocrómica/fisiopatología , Eficiencia , Medicina del Trabajo , Esfuerzo Físico , Adulto , Anemia Hipocrómica/sangre , Anemia Hipocrómica/tratamiento farmacológico , Eficiencia/efectos de los fármacos , Femenino , Compuestos Ferrosos/farmacología , Compuestos Ferrosos/uso terapéutico , Frecuencia Cardíaca/efectos de los fármacos , Hemoglobinas/análisis , Humanos , Persona de Mediana Edad , Esfuerzo Físico/efectos de los fármacos ,
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