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1.
Lancet ; 401(10386): 1438-1446, 2023 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-37004670

RESUMEN

BACKGROUND: Time-lapse monitoring is increasingly used in fertility laboratories to culture and select embryos for transfer. This method is offered to couples with the promise of improving pregnancy chances, even though there is currently insufficient evidence for superior clinical results. We aimed to evaluate whether a potential improvement by time-lapse monitoring is caused by the time-lapse-based embryo selection method itself or the uninterrupted culture environment that is part of the system. METHODS: In this three-armed, multicentre, double-blind, randomised controlled trial, couples undergoing in-vitro fertilisation or intracytoplasmic sperm injection were recruited from 15 fertility clinics in the Netherlands and randomly assigned using a web-based, computerised randomisation service to one of three groups. Couples and physicians were masked to treatment group, but embryologists and laboratory technicians could not be. The time-lapse early embryo viability assessment (EEVA; TLE) group received embryo selection based on the EEVA time-lapse selection method and uninterrupted culture. The time-lapse routine (TLR) group received routine embryo selection and uninterrupted culture. The control group received routine embryo selection and interrupted culture. The co-primary endpoints were the cumulative ongoing pregnancy rate within 12 months in all women and the ongoing pregnancy rate after fresh single embryo transfer in a good prognosis population. Analysis was by intention to treat. This trial is registered on the ICTRP Search Portal, NTR5423, and is closed to new participants. FINDINGS: 1731 couples were randomly assigned between June 15, 2017, and March 31, 2020 (577 to the TLE group, 579 to the TLR group, and 575 to the control group). The 12-month cumulative ongoing pregnancy rate did not differ significantly between the three groups: 50·8% (293 of 577) in the TLE group, 50·9% (295 of 579) in the TLR group, and 49·4% (284 of 575) in the control group (p=0·85). The ongoing pregnancy rates after fresh single embryo transfer in a good prognosis population were 38·2% (125 of 327) in the TLE group, 36·8% (119 of 323) in the TLR group, and 37·8% (123 of 325) in the control group (p=0·90). Ten serious adverse events were reported (five TLE, four TLR, and one in the control group), which were not related to study procedures. INTERPRETATION: Neither time-lapse-based embryo selection using the EEVA test nor uninterrupted culture conditions in a time-lapse incubator improved clinical outcomes compared with routine methods. Widespread application of time-lapse monitoring for fertility treatments with the promise of improved results should be questioned. FUNDING: Health Care Efficiency Research programme from Netherlands Organisation for Health Research and Development and Merck.


Asunto(s)
Fertilización In Vitro , Semen , Embarazo , Masculino , Femenino , Humanos , Imagen de Lapso de Tiempo/métodos , Índice de Embarazo , Técnicas Reproductivas Asistidas
2.
Hum Reprod ; 30(3): 603-7, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25637621

RESUMEN

STUDY QUESTION: Does intrauterine insemination in the natural cycle lead to better pregnancy rates than intracervical insemination (ICI) in the natural cycle in women undergoing artificial insemination with cryopreserved donor sperm. SUMMARY ANSWER: In a large cohort of women undergoing artificial insemination with cryopreserved donor sperm, there was no substantial beneficial effect of IUI in the natural cycle over ICI in the natural cycle. WHAT IS KNOWN ALREADY: At present, there are no studies comparing IUI in the natural cycle versus ICI in the natural cycle in women undergoing artificial insemination with cryopreserved donor sperm. STUDY DESIGN, SIZE, DURATION: We performed a retrospective cohort study among all eight sperm banks in the Netherlands. We included all women who underwent artificial insemination with cryopreserved donor sperm in the natural cycle between January 2009 and December 2010. We compared time to ongoing pregnancy in the first six cycles of IUI and ICI, after which controlled ovarian stimulation was commenced. Ongoing pregnancy rates (OPRs) over time were compared using life tables. A Cox proportional hazard model was used to compare the chances of reaching an ongoing pregnancy after IUI or ICI adjusted for female age and indication. PARTICIPANTS/MATERIALS, SETTING, METHODS: We included 1843 women; 1163 women underwent 4269 cycles of IUI and 680 women underwent 2345 cycles of ICI with cryopreserved donor sperm. MAIN RESULTS AND THE ROLE OF CHANCE: Baseline characteristics were equally distributed (mean age 34.0 years for the IUI group versus 33.8 years for the ICI group), while in the IUI group, there were more lesbian women than in the ICI group (40.6% for IUI compared with 31.8% for ICI). Cumulative OPRs up to six treatment cycles were 40.5% for IUI and 37.9% for ICI. This corresponds with a hazard rate ratio of 1.02 [95% confidence interval (CI) 0.84-1.23] after controlling for female age and indication. Increasing female age was associated with a lower OPR, in both the IUI and ICI groups with a hazard ratio for ongoing pregnancy of 0.94 per year (95% CI 0.93-0.97). LIMITATIONS, REASONS FOR CAUTION: This study is prone to selection bias due to its retrospective nature. As potential confounders such as parity and duration of subfertility were not registered, the effect of these potential confounders could not be evaluated. WIDER IMPLICATIONS OF THE FINDINGS: In women inseminated with cryopreserved donor sperm in the natural cycle, we found no substantial benefit of IUI over ICI. A randomized controlled trial with economic analysis alongside, it is needed to allow a more definitive conclusion on the cost-effectiveness of insemination with cryopreserved donor sperm. STUDY FUNDING/COMPETING INTERESTS: No funding was used and no conflicts of interest are declared.


Asunto(s)
Inseminación Artificial Heteróloga/métodos , Índice de Embarazo , Adulto , Cuello del Útero/fisiología , Criopreservación , Femenino , Humanos , Masculino , Países Bajos , Embarazo , Estudios Retrospectivos , Espermatozoides , Útero/fisiología
4.
Tijdschr Diergeneeskd ; 133(8): 330-5, 2008 Apr 15.
Artículo en Holandés | MEDLINE | ID: mdl-18505230

RESUMEN

In the period October 2003 to August 2005, 897 faecal samples were collected from wild animals and examined for Salmonella spp., Campylobacter spp., and Shiga toxin producing Escherichia coli (STEC) O157, the prevalence of which was found to be 0.1%, 13.8%, and 0.5 %, respectively. Campylobacter spp. were isolated mainly from faecal samples collected from corvidae (59.8%), and meadow birds and waterfowl (22.4%). A subset of these samples was also examined for Cryptosporidium and Giardia oocysts and cysts. None of the 247 samples examined contained C. parvum oocysts, and only 1 sample (roe faeces) contained G. lamblia assemblage A cysts. In the period September to November 2006, samples of running or still surface water were collected at 10 sites on 5 days, to investigate the presence of Salmonella spp., Campylobacter spp., and STEC O157. Twenty (40.8%) of the surface water samples were positive for one or more bacterial pathogens. Seven (14.3%) samples were positiveforSalmonella spp., 14 (28.6%) samples were positive for Campylobacter spp., and 1 (2.0%) sample was positivefor E. coli O157. Samples collected at only 2 of the 10 sites were negative for the pathogens tested; samples collected at the other 8 sites were positive for the pathogens at least once. To gain a better picture of the potential human health risk, this study should be followed up with a more quantitative study of the occurrence of human pathogens in wildlife, taking into account the different natural habitats and behaviour of the different animal populations and a possible seasonal effect. Furthermore, the contamination of surface water with human pathogens should be investigated more extensively.


Asunto(s)
Animales Salvajes/microbiología , Animales Salvajes/parasitología , Salud Pública , Microbiología del Agua , Agua/parasitología , Animales , Reservorios de Enfermedades/microbiología , Reservorios de Enfermedades/parasitología , Reservorios de Enfermedades/veterinaria , Heces/microbiología , Heces/parasitología , Humanos , Medición de Riesgo , Estaciones del Año
5.
Anim Genet ; 38(2): 168-70, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17355395

RESUMEN

A deletion in the copper metabolism (Murr1) domain containing 1 (COMMD1) gene is associated with hepatic copper toxicosis in dogs, yet evidence of copper retention in COMMD1-depleted hepatic cells has not been shown. In a dog hepatic cell line, we analysed the copper metabolic functions after an 80% (mRNA and protein) COMMD1 reduction with COMMD1-targeting siRNAs. Exposure to 64Cu resulted in a significant increase in copper retention in COMMD1-depleted cells. COMMD1-depleted cells were almost three times more sensitive to high extracellular copper concentrations. Copper-mediated regulation of metallothionein gene expression was enhanced in COMMD1-depleted cells. Based on the increased copper accumulation and enhanced cellular copper responses upon COMMD1 reduction, we conclude that COMMD1 has a major regulatory function for intracellular copper levels in hepatic cells.


Asunto(s)
Proteínas Portadoras/metabolismo , Cobre/metabolismo , Regulación de la Expresión Génica/genética , Hígado/citología , Interferencia de ARN , Proteínas Adaptadoras Transductoras de Señales , Animales , Proteínas Portadoras/genética , Línea Celular , Perros , Hígado/metabolismo , Metalotioneína/metabolismo , ARN Interferente Pequeño/genética
6.
Br Dent J ; 201(2): 66-7, 2006 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-16865107
7.
Neuroscience ; 128(1): 121-30, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15450359

RESUMEN

Numerous clinical studies have indicated that lifetime anxiety is highly prevalent in drug addicts. In the treatment of drug abuse, dually diagnosed drug addicts may benefit from pharmacological intervention strategies that alleviate the psychiatric symptomatology. We have previously shown that rats with different coping strategies in a stressful environment show strong differences in the motivation to self-administer cocaine. That is, cocaine self-administration under a progressive ratio (PR) schedule of reinforcement was enhanced in high grooming (HG) rats as compared with low grooming (LG) rats. To identify the pharmacological basis of these differences, we tested the acute effects of several anxiolytic drugs on cocaine self-administration in HG and LG rats under a PR schedule of reinforcement. Chlordiazepoxide increased PR responding in both the HG and LG rats, while the selective corticotrophin releasing hormone 1 receptor antagonist R121919 had no effect on cocaine self-administration under the PR schedule. Interestingly, buspirone and fluoxetine decreased PR responding in HG rats only and thereby abolished the individual differences in PR responding between HG and LG rats. In support of the differential effects of the serotonergic drugs on PR responding in HG and LG rats, we found that the in vitro electrically evoked release of [3H]serotonin from mesocorticolimbic brain slices was reduced in the medial prefrontal cortex, substantia nigra and nucleus accumbens core, and increased in the nucleus accumbens shell of HG rats relative to LG rats. These findings show that serotonergic anxiolytics abolish the pre-existing individual differences in cocaine self-administration between HG and LG rats, which show differences in the reactivity of serotonergic neurons. This suggests that the effectiveness of pharmacological interference may depend on the neurochemical and motivational state of the individual.


Asunto(s)
Ansiolíticos/farmacología , Ansiedad/tratamiento farmacológico , Conducta Adictiva/fisiopatología , Encéfalo/efectos de los fármacos , Trastornos Relacionados con Cocaína/fisiopatología , Automedicación , Animales , Ansiedad/complicaciones , Ansiedad/fisiopatología , Conducta Adictiva/complicaciones , Conducta Animal/efectos de los fármacos , Trastornos Relacionados con Cocaína/complicaciones , Masculino , Motivación , Neuronas/metabolismo , Ratas , Ratas Wistar , Serotonina/metabolismo
9.
Eur J Nucl Med ; 25(9): 1224-31, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9724369

RESUMEN

By using a surgical gamma probe after peritumoral injection of a radioactive tracer, the surgeon can identify the sentinel, or first, nodal site of regional metastasis in clinically node-negative patients. In the near future, the pathological status of this node will have an important impact on the treatment strategy in breast cancer and melanoma patients. This article reviews the necessary requirements for the instrument, such as: absolute sensitivity, spectral resolution, angular sensitivity and response ratio to the radioactive source at depth. In addition, ergonomic characteristics are important. The surgeon must consider the above characteristics, as they influence operational handling. Four commercially available surgical gamma probes were subjected to laboratory tests to appraise the extent to which they fulfilled these criteria. The results for each gamma probe are summarised and discussed.<


Asunto(s)
Radioisótopos de Cobalto , Ganglios Linfáticos/diagnóstico por imagen , Conteo por Cintilación/instrumentación , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Femenino , Cámaras gamma , Humanos , Cuidados Intraoperatorios/instrumentación , Masculino , Melanoma/diagnóstico por imagen , Melanoma/patología , Método de Montecarlo , Estadificación de Neoplasias , Fantasmas de Imagen , Cintigrafía
10.
Eur Respir J ; 10(4): 910-3, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9150334

RESUMEN

At the present time, plastic syringes are most commonly used for collecting arterial blood. The oxygen tension of the arterial blood (Pa,O2) in these syringes may fall. We studied the effect of the type of syringe, metabolism, and storage time on the arterial oxygen pressures measured and on the pulmonary shunt calculated. In 10 patients, 2-3 h after aortacoronary bypass surgery, a 100% oxygen test was performed. Four arterial blood gas samples were withdrawn from each patient in random order, two in glass syringes and two in plastic syringes. One glass and one plastic syringe were stored at room temperature (RT), and the others were stored in ice-water (IW). Each sample was analysed as soon as possible, and repeated 15, 30, 60 and 120 min after sampling. The Pa,O2 measurement in blood in the glass syringe in IW measured as soon as possible after sampling was considered the "gold standard". Pulmonary shunt calculations were performed using the results of the various blood gas analyses. Compared with the "gold standard", all of the other methods showed significant deterioration in the Pa,O2 measurement. The effect due to diffusion was 0.05 kPa x min(-1), and that due to metabolism 0.11 kPa x min(-1). The Pa,O2 in the glass syringes stored in IW remained stable with time. The pulmonary shunt was significantly overestimated when the "gold standard" blood gas results were not used (range 0.8-9.9%). Glass (not plastic) syringes should be used in the 100% oxygen test. The syringe should be cooled immediately, even when the sample is analysed as soon as possible.


Asunto(s)
Análisis de los Gases de la Sangre/métodos , Recolección de Muestras de Sangre/métodos , Vidrio , Consumo de Oxígeno/fisiología , Oxígeno/sangre , Jeringas , Derivación Arteriovenosa Quirúrgica , Recolección de Muestras de Sangre/instrumentación , Dióxido de Carbono/sangre , Puente de Arteria Coronaria , Seguridad de Equipos , Humanos , Ensayo de Materiales , Plásticos , Temperatura
11.
Kidney Int ; 47(1): 193-9, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7731146

RESUMEN

We performed a retrospective study of the clinical features, the pattern of the pre-treatment renal function loss, the renal morphology and the outcome in 92 patients with anti-neutrophil cytoplasmic autoantibodies directed against proteinase 3 (aPR3; N = 46) or myeloperoxidase (aMPO; N = 46). Patients with aMPO had a higher median age than patients with a PR3 (63 and 56 years; P < 0.05). The mean (+/- SD) number of affected organs in the aPR3 group exceeded that of the aMPO group (3.9 +/- 1.4 and 2.2 +/- 1.1; P < 0.01). The prevalence of renal involvement did not differ between patients with aPR3 and aMPO (83% and 67%, respectively; NS). Pre-treatment renal function deteriorated significantly faster in aPR3- than in aMPO-associated renal disease. The kidney biopsies from patients with aPR3 showed a higher activity index (10.2 +/- 3.8 and 7.3 +/- 3.2; P < 0.03) and a lower chronicity index (4.5 +/- 2.6 and 7.0 +/- 3.1; P < 0.02) than biopsies from patients with aMPO. The kidney survival at two years was 73% in patients with aPR3- and 61% in patients with aMPO-associated renal disease (NS). We conclude that renal function generally deteriorates faster in aPR3- than in aMPO-associated renal disease. This goes together with more active renal lesions in patients with aPR3 and more chronic renal lesions in patients with aMPO. Despite these differences, there is no difference in outcomes between both antibody groups.


Asunto(s)
Autoanticuerpos/análisis , Autoantígenos/inmunología , Granulomatosis con Poliangitis/inmunología , Peroxidasa/inmunología , Serina Endopeptidasas/inmunología , Adulto , Anciano , Anticuerpos Anticitoplasma de Neutrófilos , Femenino , Granulomatosis con Poliangitis/mortalidad , Granulomatosis con Poliangitis/patología , Humanos , Masculino , Persona de Mediana Edad , Mieloblastina , Poliarteritis Nudosa/inmunología , Poliarteritis Nudosa/mortalidad , Poliarteritis Nudosa/patología , Estudios Retrospectivos , Análisis de Supervivencia
12.
Int J Sports Med ; 8(5): 342-7, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2890591

RESUMEN

The effects of long-term (6 months) antihypertensive treatment with three different types of beta-blockers (propranolol, nonselective without ISA; pindolol, nonselective with ISA; metoprolol, beta 1-selective without ISA) on submaximal exercise capacity and metabolic variables during submaximal endurance exercise were studied in seven subjects with essential hypertension. Exercise tests were performed on a bicycle ergometer at 70% of estimated VO2 max. Similar reductions of resting and exercise blood pressure and exercise heart rate were obtained with the three beta-blockers. Exercise time was significantly reduced by all three beta-blockers during chronic antihypertensive therapy. The reduction tended to be more pronounced after 5-6 months of treatment than after 1 week (P = 0.06). During exercise, the plasma glycerol and nonesterified fatty acid concentrations were reduced. Plasma glucose concentration was reduced at the end of the exercise test during propranolol treatment only. Plasma lactate concentrations tended to be increased, but the difference was significant during pindolol treatment only. Oxygen uptake tended to decrease and respiratory exchange ratio to increase. Plasma potassium concentrations during exercise were significantly increased with all three beta-blockers. The effects on the metabolic variables during exercise were similar after 1 week and during long-term (20/24 weeks) beta-blocker treatment. The study shows that submaximal endurance exercise capacity is impaired in patients with essential hypertension on beta-blocker therapy and that the impairment is maintained during long-term antihypertensive beta-blocker treatment.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Metabolismo Energético/efectos de los fármacos , Prueba de Esfuerzo , Hipertensión/fisiopatología , Adulto , Electrocardiografía , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Hipertensión/tratamiento farmacológico , Masculino , Metoprolol/uso terapéutico , Persona de Mediana Edad , Resistencia Física , Pindolol/uso terapéutico , Propranolol/uso terapéutico , Distribución Aleatoria
13.
J Cardiovasc Pharmacol ; 8(5): 940-2, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-2429094

RESUMEN

The influence of prolonged submaximal exercise on the pharmacokinetics of verapamil was studied in normal volunteers both after i.v. injections of 0.13 mg/kg body weight as well as after one oral dose of 80 mg of the calcium entry blocker. Each dose was given on a rest day and on an exercise day. On the rest day, the terminal phase half-life (t1/2) of verapamil averaged 161 +/- 23 min after i.v. injection of the drug. The total clearance was 772 +/- 125 ml/min, and the area volume of distribution was 198 +/- 53 L. These parameters were not altered on the exercise day. Neither did exercise have any influence on the pharmacokinetic parameters determined after oral application of verapamil. This study shows that prolonged submaximal exercise has no influence on the pharmacokinetics of verapamil.


Asunto(s)
Esfuerzo Físico , Verapamilo/metabolismo , Administración Oral , Adulto , Femenino , Humanos , Verde de Indocianina/metabolismo , Inyecciones Intravenosas , Cinética , Masculino , Verapamilo/administración & dosificación
14.
Eur J Clin Pharmacol ; 31(3): 375-7, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3792439

RESUMEN

The pharmacokinetics of propranolol after oral and intravenous administration was studied at rest and on an exercise day in 8 healthy subjects. On the exercise day the subjects performed physical exercise for 7 h, consisting of bicycle ergometer exercise at 50% of maximal work capacity and outdoor walking. Propranolol (80 mg p.o., or 0.2 mg/kg body weight i.v.) was administered 30 min before the start of the exercise. After oral administration the terminal phase halflife, (t1/2 beta) and area under the curve (AUC) were both significantly reduced on the exercise day compared to the rest day. The bioavailability of propranolol was reduced by prolonged physical exercise and plasma levels of propranolol were about 30% lower at the end of the exercise day than at the end of the rest day. After intravenous administration, t1/2 beta was also reduced on the exercise day as compared to the rest day. AUC, clearance and volume of distribution did not differ on the two days. On the other hand, indocyanine green (ICG) clearance was significantly reduced during the bicycle ergometry periods on the exercise day. The combination of reduced ICG clearance, suggesting a reduction in hepatic blood flow, and a decreased t1/2 beta and unchanged clearance of propranolol on the exercise day was unexpected.


Asunto(s)
Esfuerzo Físico , Propranolol/metabolismo , Administración Oral , Adulto , Femenino , Humanos , Verde de Indocianina/metabolismo , Inyecciones Intravenosas , Cinética , Masculino , Propranolol/administración & dosificación , Descanso
15.
Eur J Appl Physiol Occup Physiol ; 55(5): 499-502, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3095111

RESUMEN

In a double-blind cross-over study, the effects of verapamil on the cardiovascular and metabolic changes during a progressive maximal exercise test were studied in 12 healthy volunteers. Each subject was treated with placebo and verapamil in 3 different dosages: 3 X 40, 3 X 80 and 3 X 120 mg X d-1 in random order. Drugs were administered for 2 days; on the 3rd day, 2 h after the last dose, a progressive exercise test until exhaustion was performed on a bicycle ergometer. No significant differences in maximal exercise capacity were found between the 4 groups of medication. VO2, VCO2, and VE were also unaffected by verapamil administration. Heart rate during exercise was reduced dose-dependently (p less than 0.001). With the highest dose of verapamil, maximal heart rate was reduced by 13 +/- 1 beats X min-1. No effect could be shown on parameters of carbohydrate and fat metabolism. Perceived exertion, estimated by the Borg scale, did not differ between placebo and the 3 medication groups. The study shows that despite a distinct reduction of heart rate, maximal exercise capacity remains unaffected after verapamil use.


Asunto(s)
Dióxido de Carbono/biosíntesis , Frecuencia Cardíaca/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , Esfuerzo Físico , Verapamilo/farmacología , Adulto , Presión Sanguínea/efectos de los fármacos , Ensayos Clínicos como Asunto , Método Doble Ciego , Femenino , Humanos , Masculino , Distribución Aleatoria , Verapamilo/análogos & derivados , Verapamilo/sangre
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