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2.
Ultrasound Obstet Gynecol ; 51(1): 54-63, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29077229

RESUMEN

OBJECTIVE: To compare the perinatal outcomes of singleton pregnancies resulting from blastocyst- vs cleavage-stage embryo transfer and to assess whether they differ between fresh and frozen embryo transfer cycles. METHODS: A systematic review of the literature was carried out using the Scopus, MEDLINE and ISI Web of Science databases with no time restriction. We included only peer-reviewed articles involving humans, in which perinatal outcomes of singleton pregnancies after blastocyst-stage embryo transfer were compared with those after cleavage-stage embryo transfer. Primary outcomes were preterm birth before 37 weeks and low birth weight (< 2500 g). Secondary outcomes were very preterm birth before 32 weeks, very low birth weight (< 1500 g), small-for-gestational-age (SGA), large-for-gestational-age (LGA), perinatal mortality and congenital anomaly. A meta-analysis was performed using a random-effects model. Three subgroups were evaluated: fresh only, frozen only and fresh plus frozen embryo transfer cycles. RESULTS: From a total of 3928 articles identified, 14 were selected for qualitative/quantitative analysis. Significantly higher incidences of preterm birth < 37 weeks (11 studies, n = 106 629 participants; risk ratio (RR), 1.15 (95% CI, 1.05 - 1.25); P = 0.002) and very preterm birth < 32 weeks (seven studies, n = 103 742; RR, 1.16 (95% CI, 1.02-1.31); P = 0.03) were observed after blastocyst- than after cleavage-stage embryo transfer in fresh cycles. However, the risk of preterm and very preterm birth was similar after blastocyst- and cleavage-stage transfers in frozen and fresh plus frozen cycles. Overall effect size analysis revealed fewer SGA deliveries after blastocyst- compared with cleavage-stage transfer in fresh cycles but a similar number in frozen cycles. Conversely, more LGA deliveries were observed after blastocyst- compared with cleavage-stage transfer in frozen cycles (two studies, n = 39 044; RR, 1.18 (95% CI, 1.09-1.27); P < 0.0001) and no differences between the two groups in fresh cycles (four studies, n = 42 982; RR, 1.14 (95% CI, 0.97-1.35); P = 0.11). There were no differences with respect to low birth weight, very low birth weight or congenital anomalies between blastocyst- and cleavage-stage transfers irrespective of the cryopreservation method employed. Only one study reported a higher incidence of perinatal mortality after blastocyst- vs cleavage-stage embryo transfer in frozen cycles, while no differences were found in fresh cycles. CONCLUSIONS: Our results suggest that cryopreservation of embryos can influence outcome of pregnancy conceived following blastocyst- vs cleavage-stage embryo transfer in terms of preterm birth, very preterm birth, LGA, SGA and perinatal mortality. Caution should be exercised in interpreting these findings given the low level of evidence and wide heterogeneity of the studies. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Criopreservación/métodos , Técnicas de Cultivo de Embriones/métodos , Transferencia de Embrión , Blastocisto , Transferencia de Embrión/métodos , Femenino , Humanos , Embarazo , Índice de Embarazo , Resultado del Tratamiento
3.
Phys Chem Chem Phys ; 16(44): 24173-7, 2014 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-25292161

RESUMEN

Two novel symmetrical blue squaraine sensitizers were synthesized, which exhibit panchromatic light harvesting and a record efficiency over 6% with Jsc exceeding 14 mA cm(-2), and Voc over 620 mV under 1 sun. Their color, low cost, easiness of synthesis, and relatively high photo- and thermal stability open up the way for commercial applications.

4.
J Environ Radioact ; 270: 107288, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37722230

RESUMEN

A workshop was held at the Massachusetts Institute of Technology (MIT) on July 25th and 26th, 2022. The objective was to develop a blueprint for educating next-generation engineers and scientists about nuclear waste management and disposal, which requires knowledge from diverse disciplines, including nuclear, chemical, civil, environmental, and geological science and engineering. The 49 participants included university professors, researchers, industry experts, and government officials from different areas. First, we have developed a list of key fundamental knowledge on waste management and disposal across the nuclear fuel cycle. In addition, we discussed strategies on how to teach students with diverse backgrounds through innovative teaching strategies as well as how to attract students into this area. Through the workshop, we identified the critical needs to (1) develop community resources for nuclear waste education; (2) synthesize historical perspectives, including past contamination and the management of general hazardous waste; (3) emphasize a complete life-cycle perspective, including proper waste management as the key component for energy sustainability; (4) teach students how to communicate about the key facts and risks to technical and non-technical audiences; and (5) accelerate the use of the state-of-art-technologies to attract and retain a young workforce. Furthermore, we aim to build a diverse, inclusive community that supports students in developing their own narratives about nuclear waste, particularly in recognizing that antagonistic views have been important to improving safety and protecting public health and the environment.


Asunto(s)
Monitoreo de Radiación , Residuos Radiactivos , Administración de Residuos , Humanos
6.
Diabetes Care ; 14(7): 602-4, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1914803

RESUMEN

OBJECTIVE: To evaluate a new computerized method for recording 7-day food intake. RESEARCH DESIGN AND METHODS: Randomized crossover trial was conducted with patients recording the amount and type of every food and drink consumed during a week by either a computerized device (Food-meter) or recording the data in a diary. Each method was applied twice. Twenty-one insulin-dependent diabetic patients (mean +/- SD age 25 +/- 9 yr) were studied. RESULTS: The two methods showed very good agreement in the evaluation of the patients' diets (1792 +/- 408 vs. 1764 +/- 436 kcal/day, 84 +/- 19 vs. 82 +/- 21 g/day protein, 68 +/- 22 vs. 67 +/- 23 g/day fat, 210 +/- 60 vs. 207 +/- 58 g/day carbohydrate with the conventional and computerized methods, respectively). The variability between the methods and the variability within each method were of similar magnitude. CONCLUSIONS: The Food-meter represents a useful tool for computerizing the 7-day food record. The method is easy, reliable, and time saving. Moreover, it minimizes the risk of transcriptional errors.


Asunto(s)
Sistemas de Computación/normas , Diabetes Mellitus Tipo 1/dietoterapia , Ingestión de Alimentos , Participación del Paciente/métodos , Adulto , Análisis de Varianza , Femenino , Alimentos , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
7.
Am J Clin Nutr ; 51(3): 338-42, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2309640

RESUMEN

Circulating concentrations of albumin and the labile proteins prealbumin (PA) and retinol-binding protein (RBP) were evaluated over 20 d in five groups of obese patients. The patients were given four types of very-low-calorie diets (VLCDs) (less than 500 kcal/d) that provided different amounts of protein or carbohydrate (CHO) plus protein and a conventional 1200-kcal/d hypocaloric diet. Serum albumin concentrations did not vary significantly during any of the diets whereas PA and RBP remained unchanged only during the conventional 1200-kcal/d diet. Similar and significant decreases of serum PA and RBP were observed during the VLCDs studied. The molar ratio of RBP to PA did not vary during dieting. Thus, when less than 500 kcal/d are given, changes of serum short-half-life visceral proteins are not affected by either the addition of CHO to protein or the changes in protein intake. Moreover, serum albumin concentration and RBP/PA do not vary during VLCDs.


Asunto(s)
Dieta Reductora , Carbohidratos de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Obesidad/sangre , Prealbúmina/análisis , Proteínas de Unión al Retinol/análisis , Albúmina Sérica/análisis , Adulto , Ingestión de Energía , Metabolismo Energético , Femenino , Humanos , Masculino , Obesidad/dietoterapia , Pérdida de Peso
8.
Chest ; 97(3): 611-7, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2106410

RESUMEN

The distribution of antibiotics into cardiac valvular tissues is incompletely understood. By integrative computer modeling, we have used previously obtained pharmacokinetic data in experimental endocarditis to characterize aminoglycoside distribution within various geographic sectors of aortic vegetations of rabbits and humans in the current study. In rabbits with pseudomonal aortic endocarditis receiving a standard regimen of amikacin (15 mg/kg every eight hours), sub-MBC levels of the drug for the infecting organism were calculated in the center of 0.38-cm vegetations; this occurred despite supra-MBC levels calculated in plasma and more peripheral loci of the vegetation. In contrast, with a high-dose regimen of amikacin (40 mg/kg every eight hours), supra-MBC drug levels were calculated throughout the entire vegetation for at least 50 percent of the dosing interval. Using similar computer-generated approaches, these data in the rabbit were approximately in simulated aminoglycoside penetration of 10-mm human aortic vegetations. Aminoglycoside regimens designed to yield supra-MBC serum levels in both normal and rapid drug eliminators consistently achieved sub-MBC levels in the center of the vegetation. Computer simulations also confirmed that daily doses of aminoglycoside at least two to four times higher than those ordinarily recommended are necessary to consistently achieve uniform supra-MBC intravegetation levels for an entire dosing interval. Such computer-generated data support the concept of maldistribution of aminoglycosides in aortic endocarditis and provide a rationale for investigating the use of high-dose regimens of aminoglycoside in treating experimental endocarditis.


Asunto(s)
Amicacina/farmacocinética , Enfermedades de la Aorta/metabolismo , Simulación por Computador , Endocarditis Bacteriana/metabolismo , Infecciones por Pseudomonas/metabolismo , Amicacina/administración & dosificación , Amicacina/sangre , Animales , Antibacterianos/administración & dosificación , Antibacterianos/farmacocinética , Enfermedades de la Aorta/sangre , Enfermedades de la Aorta/patología , Difusión , Esquema de Medicación , Endocarditis Bacteriana/sangre , Endocarditis Bacteriana/patología , Humanos , Infecciones por Pseudomonas/sangre , Infecciones por Pseudomonas/patología , Pseudomonas aeruginosa , Conejos
9.
Clin Nutr ; 12(1): 1-7, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16843268

RESUMEN

Basal energy expenditure (BEE) was either measured by indirect calorimetry or predicted by different formulae in 104 young women: 74 lean and overweight subjects (normal weight, NWt) and 30 obese subjects. The predictive equations were based on weight alone (Owen, FAO-1, Schofield-1) or on weight and height (Harris-Benedict, Mifflin, Kleiber, and again FAO-2 and Schofield-2). With the exception of the Owen equation all the equations over-estimated measured BEE in both study groups. The ratio between measured and predicted value (% MP) varied between 102.3 (Owen) and 87.7 (Kleiber) in the NWt subjects and between 113.2 (Owen) and 89.3 (Schofield-1) in the obese subjects. The range including 95% of the predicted-measured differences (PMdiff) was larger than 1700 kJ/d in the NWt group and 2300 kJ/d in the obese group. In both study groups most of the equations showed a significant relationship between PMdiff and/or % MP with body weight and the magnitude of BEE. In conclusion, these equations are of little help in predicting BEE in a single subject and should be used with caution when assessing energy requirements in populations or groups of subjects.

10.
Eur J Clin Nutr ; 43(7): 453-63, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2806197

RESUMEN

Dietary intake for 18 nutrients in a sample of 230 free-living elderly people in Naples was assessed by three dietary assessment methods (diet history, 24-h recall and 3-d record). Different statistical criteria (the correlation coefficient, the mean difference and the proportion of individuals placed in the same thirds of distribution) were used to evaluate the agreement among different methods. Theoretical considerations are shown demonstrating the uselessness of the correlation coefficient in evaluating the agreement. In analysing the mean differences, diet history gave higher estimates of nutrient intake and 24-h recall gave lower estimates, when compared to the 3-d record. Large standard errors for the mean differences and small proportions of individuals placed in the same thirds of the distribution, for nearly all the nutrients examined, showed poor agreement among the three different methods. These findings strongly suggest the presence of bias in, at least, two of the three dietary assessment methods. Some statistical techniques for improving the diet record method in epidemiological studies are discussed: the need to transform nutrient intake data to achieve normality in the distribution; the number of days of recording required to produce a valid study; and the need to evaluate the bias in the diet record.


Asunto(s)
Dieta , Anciano , Anciano de 80 o más Años , Interpretación Estadística de Datos , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Métodos , Encuestas Nutricionales
11.
Int J Cardiol ; 36(2): 197-201, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1512058

RESUMEN

The prevalence of significant hypertension in childhood may be higher than expected. We have measured sitting blood pressure in 168 11-yr-old children attending a pre-high school in the Neapolitan area on four occasions over a 3-month period. We have also measured blood pressure and heart rate during a mental arithmetic test and during isometric exercise. Prevalence of significant hypertension (diastolic blood pressure 82-90 mmHg) was 13% at the first visit and decreased to 6.5% at the last visit; prevalence of severe hypertension (diastolic blood pressure greater than or equal to 90 mmHg) decreased from 5.4% to 1.2% from the 1st to the 4th visit. No sex-related difference was observed. A more frequently positive family history of hypertension (50% vs 30% in the fifth and first quintile of blood pressure, respectively) and higher body weight (body mass index = 21.4 vs 19.3 kg/m2) were found in children in the 5th quintile of blood pressure distribution. Blood pressure increased during mental arithmetic by 10/13% of the resting values in the first quintile and by 6/11% in the last one during mental test; during handgrip the increase was of 20/37% and 24/46%, respectively: differences between quintiles did not reach statistical significance. These data show that about 8% of a Neapolitan sample of school population have high blood pressure levels, while no difference in vascular reactivity to sympathetic stimulation was detected in children with higher blood pressure.


Asunto(s)
Presión Sanguínea , Hipertensión/epidemiología , Sistema Nervioso Simpático/fisiopatología , Factores de Edad , Niño , Ejercicio Físico , Femenino , Humanos , Hipertensión/fisiopatología , Italia/epidemiología , Masculino , Matemática , Descanso , Factores Sexuales , Estrés Psicológico
12.
Minerva Endocrinol ; 15(4): 239-43, 1990.
Artículo en Italiano | MEDLINE | ID: mdl-2099992

RESUMEN

The use of impedance analysis is becoming increasingly widespread as a safe, non-invasive and quick method to assess body composition. Numerous equations, based on variables derived from anthropometric variables as well as from impedance measurements analysis, have been developed to predict the alipidic mass from the resulting analysis. The most frequently used statistical method is the least squares technique. The inadequate reliability of this statistical technique is examined in this study and the use of the technique known as "ridge regression" is suggested.


Asunto(s)
Composición Corporal , Tejido Adiposo , Adolescente , Adulto , Fenómenos Biofísicos , Biofisica , Femenino , Humanos , Análisis de los Mínimos Cuadrados , Análisis de Regresión
13.
Minerva Endocrinol ; 16(1): 37-41, 1991.
Artículo en Italiano | MEDLINE | ID: mdl-1944015

RESUMEN

Fat free mass (FFM) predicted by five bioelectrical impedance (BIA) available formulae (Segal et al., Lukaski et al., Kushner et al., Deurenberg et al., manufacturer's predictive equation) was compared with densitometrically-determined FFM (as a reference method) in two groups of young women with different anthropometric characteristics. In the farmers (very short and light individuals), none of the studied formulae was able to accurately predict FFM: this latter was overestimated in subjects with low and underestimated in those with high FFM. In the other group (INCAP employees), only values predicted by Lukaski formula were in perfect agreement with FFM, showing no bias depending on FFM changes. In conclusion, the available BIA formulae seem to be specific for population from which they were derived and could not be used on samples from other populations if not cross-validated.


Asunto(s)
Antropometría/métodos , Composición Corporal , Pletismografía de Impedancia , Adolescente , Adulto , Agricultura , Estatura , Índice de Masa Corporal , Femenino , Humanos , Matemática , Personal de Hospital , Caracteres Sexuales , Factores Socioeconómicos , Somatotipos
14.
J Agric Food Chem ; 48(4): 1041-6, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10775346

RESUMEN

The formation of color and Maillard reaction products in two model systems consisting of lactose and lysine or N(alpha)-acetyllysine has been investigated. During heating, the blockage of the N(alpha) group of lysine determined a faster color and antioxidative ability development compared to the system with free lysine. This is combined to a greater amount of melanoidin formation in the acetylated lysine system, while in the free lysine system a higher amount of pyrraline and hydroxymethyl furfural were detected. The pattern of low molecular weight products suggests that 3-deoxyglucosone and 1-deoxyglucosone degradation pathways are favored for free lysine and N(alpha)-acetyllysine, respectively. Whole data allow us to hypothesize that in a lactose-N(alpha)-acetyllysine model system the formation of colored high molecular weight polymer proceeds faster because less material is dispersed in reaction pathways, mainly the Strecker degradation, which leads to small and intermediate molecular weight products.


Asunto(s)
Lactosa/química , Lisina/análogos & derivados , Lisina/química , Reacción de Maillard , Antioxidantes , Cromatografía Líquida de Alta Presión , Color , Calor , Espectrometría de Masas
15.
Food Chem Toxicol ; 41(10): 1367-74, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12909270

RESUMEN

Melanoidins, the brown-colored polymers formed through Maillard type reaction in several heat-treated foods, represent a significant part of our diet, with an average intake of grams per day. Most of the studies on the physiological effects of these compounds have been performed using the water soluble melanoidin fractions. But dietary melanoidins formed on the surface of bakery products are poorly soluble in water as well as in organic solvents. In this work, an enzymatic solubilization procedure was developed on a gluten-glucose model system and it was applied to bread and biscuits. The soluble material obtained was tested for its antioxidant activity, for its effect on phase-I and phase-II xenobiotic enzymes and for potential cytotoxic effects. Soluble melanoidins from model system and biscuits exhibit a strong antioxidant activity and do not show any cytotoxicity on Caco-2 cells. Melanoidins extracted from biscuits was able to inhibit the activity of Phase I (NADPH-cytochrome-c reductase) and Phase II (Glutathione-S-transferase) enzymes, whereas the low molecular weight melanoidins isolated from gluten-glucose model system inhibit the activity of NADPH-cytochrome-c reductase.


Asunto(s)
Pan/análisis , Pan/toxicidad , Polímeros/química , Polímeros/toxicidad , Antioxidantes/química , Células CACO-2 , Supervivencia Celular/efectos de los fármacos , Glutatión Reductasa/metabolismo , Glútenes/química , Calor , Humanos , Hidrólisis , Cinética , Peso Molecular , NADPH-Ferrihemoproteína Reductasa/metabolismo , Pronasa/química , Ácido Tricloroacético/química , Xenobióticos/metabolismo
16.
Adv Exp Med Biol ; 348: 149-53, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8172018

RESUMEN

Up until now, conflicting results have been reported on the association between serum cholesterol and risk of breast cancer in women. In this study, the serum concentrations of cholesterol, HDL-cholesterol, triglycerides and total lipids in women with breast cancer (BC) have been compared to those of women with benign breast disease (BBD). BC women had higher serum concentration of HDL-cholesterol both in pre- and in post-menopausal age. No difference was observed in the serum concentration of total cholesterol, triglycerides and total lipids. These findings could be explained by an increased estrogen activity which is believed to be involved in the development of breast cancer, and in the modulation of lipid metabolism (lowering LDL-cholesterol and increasing HDL-cholesterol). High serum HDL-cholesterol could be a biochemical index of increased risk of having breast cancer.


Asunto(s)
Neoplasias de la Mama/sangre , HDL-Colesterol/sangre , Posmenopausia , Premenopausia , Adulto , Enfermedades de la Mama/sangre , Femenino , Humanos , Italia , Lípidos/sangre , Persona de Mediana Edad , Factores de Riesgo
17.
Int J Vitam Nutr Res ; 58(3): 343-50, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3198323

RESUMEN

Several studies have investigated the relationship between obesity and mortality or cardiovascular disease (CVD) reporting conflicting results. The very few data collected on extremely obese patients have shown an increased mortality in these patients compared to the general population. Two hundred and sixtyfour (182 f, 82 m) severely obese patients (BMI greater than or equal to 35 w/h2) living in Southern Italy (hospitalized from 1972 to 1985 in our Metabolic Unit for a weight reduction program) were followed-up for a mean period of 7.1 years. Twentynine (20f, 9m) deaths were recorded during the follow-up. Higher mortality was found at all ages and in both sexes in these patients when compared to the general italian population. The excess mortality reached its peak in the age range 25-54 yrs (observed/expected mortality rate was 6.9 in females and 4.32 in males) diminishing by aging in both sexes (3.52 in females and 1.56 in males in age range 55-72 yrs). Death from CV disease was found more frequent than in the general italian population but it was unable to fully explain the excess mortality. Predictive factors of mortality were: in females age, BMI, and serum glucose and in males only age. In conclusion severely obese patients living in Southern Italy have a very high mortality rate. The excess mortality is not fully explained by cardiovascular disease.


Asunto(s)
Obesidad/mortalidad , Análisis Actuarial , Adolescente , Adulto , Factores de Edad , Anciano , Enfermedades Cardiovasculares/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Factores de Riesgo , Factores Sexuales , Pérdida de Peso
18.
Int J Vitam Nutr Res ; 58(2): 236-40, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3170099

RESUMEN

Aim of this study was to evaluate whether the age of onset of obesity might affect the prevalence of CV risk factors in severely obese patients. Five hundred forty-five (385 F aged 42.3 +/- 7.1 yrs, BMI 47.3 +/- 5.1 w/h2 and 160 M of 39.0 +/- 1.1 yrs and BMI of 41.8 +/- 5.3 w/h2) severely obese patients hospitalized in the Metabolic Unit between 1972 and 1985 were subdivided in four classes according to the age of onset of obesity. Severely obese women with maturity onset obesity (i.e. onset greater than or equal to 20 yrs) (MOO) had higher (p less than or equal to .01) serum glucose (118 vs 103 mg/dl) and triglyceride (167 vs 126 mg/dl) than those with early onset obesity (EOO) (i.e. onset less than or equal to 3 yrs) with the same age, BMI and smoking habits. Similar trend was also found in men. In males arterial blood pressure was found to be higher (p less than or equal to .01) in EOO than in MOO (SBP = 152 vs 133 mmHg and DBP = 92 vs 83 mmHg). Similar trend was found in females. In conclusion age of onset of obesity may, at least in part, affect the prevalence of cardiovascular risk factors in severe obesity.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Obesidad/complicaciones , Adulto , Factores de Edad , Enfermedades Cardiovasculares/diagnóstico , Diabetes Mellitus , Femenino , Humanos , Hipercolesterolemia/etiología , Hiperlipoproteinemia Tipo IV/etiología , Hipertensión/etiología , Masculino , Persona de Mediana Edad , Factores de Riesgo
20.
BMJ ; 297(6644): 358, 1988 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-3416174
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