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1.
Appl Opt ; 59(10): 3285-3295, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32400613

RESUMEN

We present two prescriptions for broadband ($ {\sim} 77 - 252\;{\rm GHz} $), millimeter-wave antireflection coatings for cryogenic, sintered polycrystalline aluminum oxide optics: one for large-format (700 mm diameter) planar and plano-convex elements, the other for densely packed arrays of quasi-optical elements-in our case, 5 mm diameter half-spheres (called "lenslets"). The coatings comprise three layers of commercially available, polytetrafluoroethylene-based, dielectric sheet material. The lenslet coating is molded to fit the 150 mm diameter arrays directly, while the large-diameter lenses are coated using a tiled approach. We review the fabrication processes for both prescriptions, then discuss laboratory measurements of their transmittance and reflectance. In addition, we present the inferred refractive indices and loss tangents for the coating materials and the aluminum oxide substrate. We find that at 150 GHz and 300 K the large-format coating sample achieves $ (97 \pm 2)\% $ transmittance, and the lenslet coating sample achieves $ (94 \pm 3)\% $ transmittance.

2.
Nature ; 495(7441): 344-7, 2013 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-23485967

RESUMEN

In the past decade, our understanding of galaxy evolution has been revolutionized by the discovery that luminous, dusty starburst galaxies were 1,000 times more abundant in the early Universe than at present. It has, however, been difficult to measure the complete redshift distribution of these objects, especially at the highest redshifts (z > 4). Here we report a redshift survey at a wavelength of three millimetres, targeting carbon monoxide line emission from the star-forming molecular gas in the direction of extraordinarily bright millimetre-wave-selected sources. High-resolution imaging demonstrates that these sources are strongly gravitationally lensed by foreground galaxies. We detect spectral lines in 23 out of 26 sources and multiple lines in 12 of those 23 sources, from which we obtain robust, unambiguous redshifts. At least 10 of the sources are found to lie at z > 4, indicating that the fraction of dusty starburst galaxies at high redshifts is greater than previously thought. Models of lens geometries in the sample indicate that the background objects are ultra-luminous infrared galaxies, powered by extreme bursts of star formation.

3.
Ultrasound Obstet Gynecol ; 51(6): 806-812, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28452086

RESUMEN

OBJECTIVE: Brain injury in neonates born prematurely is associated strongly with poor neurodevelopmental outcome. The aim of this study was to evaluate whether tocolysis with nifedipine or atosiban in women with threatened preterm birth can reduce the incidence of overall brain injury in neonates born prematurely. METHODS: This was a secondary analysis of the APOSTEL-III trial (Dutch Clinical Trial Registry, no. NTR2947), a randomized clinical trial in which women with threatened preterm labor between 25 and 34 weeks of gestation were allocated to treatment with nifedipine or atosiban. In this secondary analysis, women delivered at ≤ 32 weeks of gestational age in the two main contributing centers were included. Primary outcome was the presence of neonatal brain injury, which was defined as presence of abnormalities on ultrasound investigation and classified into mild and severe. To evaluate type and severity of brain injury, all neonatal ultrasounds performed during neonatal intensive and medium care admission were analyzed. To test the robustness of our results, a sensitivity analysis was performed assessing differences in baseline or known risk factors for brain injury. RESULTS: A total of 117 neonates (from 102 women) were studied, of which 51 had been exposed to nifedipine and 66 to atosiban. Brain injury was observed in 22 (43.1%) neonates in the nifedipine group compared with 37 (56.1%) in the atosiban group (OR, 0.60; 95% CI, 0.29-1.24). Presence of mild brain injury was comparable between the nifedipine (33.3%) and atosiban (48.5%) groups (OR, 0.53; 95% CI, 0.25-1.13). Severe brain injury was also comparable between the groups, observed in 9.8% of neonates in the nifedipine vs 7.6% of those in the atosiban group (OR, 1.33; 95% CI, 0.36-4.85). Intraventricular hemorrhage (≥ Grade I) was the most frequently seen ultrasound abnormality, observed in 18 (35.3%) neonates in the nifedipine group vs 25 (37.9%) in the atosiban group (OR, 0.90; 95% CI, 0.42-1.91). The sensitivity analysis, with adjustment for maternal age and gestational age at randomization, showed no statistical difference between the groups for presence of brain injury (OR, 0.58; 95% CI, 0.27-1.27). CONCLUSION: In children born before 32 weeks of gestation after the use of tocolytics, the prevalence of brain injury was high. No significant differences were found with respect to overall brain injury between neonates exposed to nifedipine and those exposed to atosiban. However, as this study was a secondary analysis of the APOSTEL III trial, it was underpowered for brain injury. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Lesiones Encefálicas/prevención & control , Nifedipino/uso terapéutico , Nacimiento Prematuro/prevención & control , Tocolíticos/uso terapéutico , Vasotocina/análogos & derivados , Administración Intravenosa , Adulto , Lesiones Encefálicas/congénito , Femenino , Edad Gestacional , Humanos , Recién Nacido , Masculino , Nifedipino/administración & dosificación , Embarazo , Resultado del Embarazo , Tocolíticos/administración & dosificación , Resultado del Tratamiento , Vasotocina/administración & dosificación , Vasotocina/uso terapéutico
4.
Nature ; 488(7411): 349-52, 2012 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-22895340

RESUMEN

In the cores of some clusters of galaxies the hot intracluster plasma is dense enough that it should cool radiatively in the cluster's lifetime, leading to continuous 'cooling flows' of gas sinking towards the cluster centre, yet no such cooling flow has been observed. The low observed star-formation rates and cool gas masses for these 'cool-core' clusters suggest that much of the cooling must be offset by feedback to prevent the formation of a runaway cooling flow. Here we report X-ray, optical and infrared observations of the galaxy cluster SPT-CLJ2344-4243 (ref. 11) at redshift z = 0.596. These observations reveal an exceptionally luminous (8.2 × 10(45) erg s(-1)) galaxy cluster that hosts an extremely strong cooling flow (around 3,820 solar masses a year). Further, the central galaxy in this cluster appears to be experiencing a massive starburst (formation of around 740 solar masses a year), which suggests that the feedback source responsible for preventing runaway cooling in nearby cool-core clusters may not yet be fully established in SPT-CLJ2344-4243. This large star-formation rate implies that a significant fraction of the stars in the central galaxy of this cluster may form through accretion of the intracluster medium, rather than (as is currently thought) assembling entirely via mergers.

5.
BMC Pediatr ; 18(1): 147, 2018 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-29720158

RESUMEN

BACKGROUND: There is increasing evidence that neonatal seizures in term neonates with stroke, asphyxia or brain haemorrhage might be associated with adverse neurodevelopment and development of epilepsy. The extent of this association is not known. The objective of this study was to assess the possible impact of neonatal seizures on these outcomes and if possible calculate a relative risk. METHODS: A systematic review and meta-analysis was performed (study period January 2000-June 2015). PubMed, Medline and Embase were searched for cohort studies evaluating neurodevelopmental outcome at the age of at least 18 months or development of epilepsy in surviving term neonates with or without neonatal seizures. The methodological quality of included studies was assessed and data extractions were performed in a standardized manner by independent reviewers. Pooled Relative Risks (RR) with 95% confidence intervals for adverse outcome were calculated if possible. RESULTS: Out of 1443 eligible studies 48 were selected for full text reading leaving 9 cohort studies for the final analyses (4 studies on stroke, 4 on perinatal asphyxia and one on cerebral hemorrhage). For all cases with stroke or asphyxia combined the pooled risk ratio (RR) for adverse outcome when suffering neonatal seizures was 7.42 (3.84-14.34); for neonates with perinatal asphyxia: 8.41 (4.07-17.39) and for neonates with stroke: 4.95 (1.07-23.0). The pooled RR for development of late onset epilepsy could only be determined for infants suffering from stroke: 1.48 (0.82-2.68). Results were biased and evidence sparse. CONCLUSIONS: The presence of neonatal seizures in term newborns with vascular or hypoxic brain injury may have an impact on or be a predictor of neurodevelopmental outcome. The biased available data yield insufficient evidence about the true size of this association.


Asunto(s)
Asfixia Neonatal/complicaciones , Hemorragia Cerebral/complicaciones , Hipoxia Encefálica/complicaciones , Trastornos del Neurodesarrollo/etiología , Convulsiones/complicaciones , Accidente Cerebrovascular/complicaciones , Epilepsia/etiología , Humanos , Recién Nacido , Pronóstico , Factores de Riesgo
6.
Trials ; 25(1): 248, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38594733

RESUMEN

BACKGROUND: Family Integrated Care (FICare) has demonstrated positive outcomes for sick neonates and has alleviated the psychological burden faced by families. FICare involves structured training for professionals and caregivers along with the provision of resources to offer physical and psychological support to parents. However, FICare implementation has been primarily limited to developed countries. It remains crucial to assess the scalability of this model in overcoming social-cultural barriers and conduct a cost-effectiveness analysis. The RISEinFAMILY project aims to develop an adapted FICare model that can serve as the international standard for neonatal care, accommodating various cultural, architectural, and socio-economic contexts. METHODS: RISEinFAMILY is a pluri-cultural, stepped wedge cluster controlled trial conducted in Spain, Netherlands, the UK, Romania, Turkey, and Zambia. Eligible participants include infant-family dyads admitted to the Neonatal Intensive Care Unit (NICU) requiring specialised neonatal care for a minimum expected duration of 7 days, provided there are no comprehension barriers. Notably, this study will incorporate a value of implementation analysis on FICare, which can inform policy decisions regarding investment in implementation activities, even in situations with diverse data. DISCUSSION: This study aims to evaluate the scalability and adaptation of FICare across a broader range of geographical and sociocultural contexts and address its sustainability. Furthermore, it seeks to compare the RISEinFAMILY model with standard care, examining differences in short-term newborn outcomes, family mental health, and professional satisfaction. TRIAL REGISTRATION: ClinicalTrials.gov NCT06087666. Registered on 17 October 2023. PROTOCOL VERSION: 19 December 2022; version 2.2.


Asunto(s)
Recien Nacido Prematuro , Unidades de Cuidado Intensivo Neonatal , Recién Nacido , Lactante , Humanos , Cuidadores , Padres/psicología , Consejo , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
Phys Rev Lett ; 111(14): 141301, 2013 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-24138230

RESUMEN

Gravitational lensing of the cosmic microwave background generates a curl pattern in the observed polarization. This "B-mode" signal provides a measure of the projected mass distribution over the entire observable Universe and also acts as a contaminant for the measurement of primordial gravity-wave signals. In this Letter we present the first detection of gravitational lensing B modes, using first-season data from the polarization-sensitive receiver on the South Pole Telescope (SPTpol). We construct a template for the lensing B-mode signal by combining E-mode polarization measured by SPTpol with estimates of the lensing potential from a Herschel-SPIRE map of the cosmic infrared background. We compare this template to the B modes measured directly by SPTpol, finding a nonzero correlation at 7.7σ significance. The correlation has an amplitude and scale dependence consistent with theoretical expectations, is robust with respect to analysis choices, and constitutes the first measurement of a powerful cosmological observable.

8.
Arch Dis Child Fetal Neonatal Ed ; 109(1): 41-45, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37369599

RESUMEN

BACKGROUND: Perinatal asphyxia may be followed by multiple organ dysfunction (MOD) and is often included in prognostication of the individual patient, but evidence of discriminating accuracy is lacking. The aim of this study was to assess whether MOD in asphyxiated neonates during therapeutic hypothermia (TH) predicts mortality or neurodevelopmental impairment (NDI) at 24 months of age and which peripartum variables are associated with the onset of MOD. METHODS: A retrospective analysis of a prospective cohort study of asphyxiated newborns undergoing TH was performed. MOD was defined as dysfunction of the brain (encephalopathy) combined with two or more organ systems. Outcome was routinely assessed by standardised developmental testing at the age of 24 months. The predictive accuracy of MOD on the combined outcome and its components (death and NDI) was expressed as areas under the receiver operating characteristic curves (AUROCs). The associations of peripartum variables and development of MOD were expressed as ORs and their CIs. RESULTS: 189 infants (median gestation 40 (range 36-42 weeks) with moderate to severe hypoxic ischaemic encephalopathy were included. 47% developed MOD. The prediction of the combined 24-month outcome or its components showed AUROCs <0.70. Associated with MOD were pH at birth (OR 0.97, CI 0.95 to 0.99), lactate at birth (OR 1.09, CI 1.04 to 1.15), Base Excess (BE) at birth (OR 0.94, CI 0.90 to 0.99) and epinephrine administration during resuscitation (OR 2.09, CI 1.02 to 4.40). CONCLUSION: MOD has a low discriminating accuracy in predicting mortality or NDI at 24 months age and might not be useful for prognostication. Signs of acid-base disturbance and adrenalin use at birth are associated with the development of MOD.


Asunto(s)
Asfixia Neonatal , Hipotermia Inducida , Hipoxia-Isquemia Encefálica , Accidente Cerebrovascular , Lactante , Humanos , Recién Nacido , Preescolar , Estudios de Cohortes , Hipoxia-Isquemia Encefálica/etiología , Hipoxia-Isquemia Encefálica/terapia , Hipoxia-Isquemia Encefálica/diagnóstico , Estudios Retrospectivos , Estudios Prospectivos , Insuficiencia Multiorgánica/complicaciones , Insuficiencia Multiorgánica/terapia , Asfixia Neonatal/complicaciones , Asfixia Neonatal/terapia , Asfixia Neonatal/diagnóstico , Accidente Cerebrovascular/complicaciones , Hipotermia Inducida/efectos adversos
9.
Eur J Paediatr Neurol ; 12(1): 41-5, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17537653

RESUMEN

We report a case of neonatal dural sinus malformation already visible on antenatal ultrasound. This is a rare disease entity in infants and children. Clinical diagnosis was made by demonstrating a cranial murmur on auscultation; macrocrania and signs of progressive cardiac failure. Imaging studies as cerebral ultrasound, postnatal MRI scan and MR angiography demonstrated a large dural sinus malformation originating from the sagittal sinus with extensive arteriovenous fistulae. Due to the extent of the lesion, the existing ischemic brain damage and involvement of the torcular, no therapeutic options were available and the child died of irreversible cardiac failure. The diagnosis was confirmed with autopsy. We discuss the clinical presentation, imaging and neuropathological results and relate our findings to embryological data and the existing literature.


Asunto(s)
Malformaciones Vasculares del Sistema Nervioso Central , Senos Craneales/patología , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Malformaciones Vasculares del Sistema Nervioso Central/patología , Malformaciones Vasculares del Sistema Nervioso Central/fisiopatología , Humanos , Recién Nacido , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Radiografía
10.
BJOG ; 115(1): 76-81, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18053103

RESUMEN

OBJECTIVE: To examine (1) the incidence of fetal thrombocytopenia in hydropic fetuses with congenital B19 virus infection, (2) the effect of intrauterine platelet transfusions and (3) the correlation between fetal B19 viral load and severity of thrombocytopenia. DESIGN: Retrospective analysis of data from prospectively collected fetal blood samples. SETTING: Leiden University Medical Centre, the national centre for management of intrauterine fetal disease in the Netherlands. POPULATION: Thirty hydropic fetuses treated with intrauterine red blood cell and platelet transfusions for human B19 virus-induced severe fetal anaemia and thrombocytopenia over a 10-year period. METHODS: Fetal blood samples (n= 30) taken before and after intrauterine transfusion were investigated. No cases were excluded, and there was no loss to follow up. MAIN OUTCOME MEASURES: Parameters recorded were gestational age, experienced fetal movements, gravidity and parity, severity of fetal hydrops, severity of fetal anaemia and thrombocytopenia and megakaryocyte and reticulocyte counts. Survival and procedure-associated complications were documented. Quantitative B19 viral load measurements were performed on all fetal samples. RESULTS: Forty-six percent of all hydropic fetuses showed severe thrombocytopenia. No antenatal intracerebral haemorrhage or procedure-associated bleeding occurred. Overall, survival was 77%. Platelet counts increased following platelet transfusion and decreased significantly following red blood cell transfusion alone. No correlation was found between fetal viral loads and platelet counts. CONCLUSION: Thrombocytopenia was frequently encountered in fetal B19V infection, but fetal bleeding complications were not noted. Absence of a direct relationship between fetal B19 viral load and platelet counts suggests a temporal dissociation between these findings. Dilutional thrombocytopenia is frequently seen in the fetus following red blood cell transfusion alone. The clinical significance of this phenomenon is unclear. The risk of fluid overload by fetal platelet transfusion in a severely hydropic fetus should be weighed against the low incidence of fetal bleeding complications.


Asunto(s)
Anemia/complicaciones , Hidropesía Fetal/virología , Infecciones por Parvoviridae/complicaciones , Parvovirus B19 Humano , Trombocitopenia/virología , Adulto , Plaquetas/virología , Transfusión de Sangre Intrauterina/métodos , Femenino , Sangre Fetal/virología , Hemoglobinas/análisis , Humanos , Recuento de Leucocitos , Transfusión de Plaquetas/métodos , Embarazo , Estudios Prospectivos , Estudios Retrospectivos , Trombocitopenia/terapia , Carga Viral
11.
Ned Tijdschr Geneeskd ; 152(21): 1185-90, 2008 May 24.
Artículo en Neerlandesa | MEDLINE | ID: mdl-18578441

RESUMEN

Four pregnant women, aged 29, 32, 36 and 36 years, respectively, were diagnosed with Human parvovirus B19 (B19V) infection. Only the first woman had exanthema and fever. In the first three cases, the source of infection appeared to be another child; two of these children were infected during a school outbreak. All four foetuses were infected, but the first foetus was asymptomatic and healthy at birth. The second foetus had anaemia and increased blood flow in the middle cerebral artery; it received an intrauterine transfusion and was healthy at birth. The third foetus was almost immobile and had cardiomegaly and hydrops fetalis; it was dead upon induced birth. In the fourth case, pregnancy was uneventful until two days before parturition, when the mother reported a decrease in foetal movement. The infant was born and developed respiratory insufficiency after 8 hours. Imaging revealed multiple bilateral lesions in frontal, occipital and parietal white matter consistent with infarction. The infant died after 5 days. Infection with B19V is associated with a wide range of clinical presentations and outcomes. Effects may range from an uncomplicated pregnancy to severe hydrops fetalis or intrauterine foetal death. Maternal symptoms may be aspecific, which complicates early diagnosis. When maternal B19V infection is suspected, immediate investigation for recent B19V infection should be performed. Quantitative B19 viral load measurements may provide insight into the stage of infection and may guide foetal monitoring. Referral to a foetal therapy unit is essential for hydrops fetalis or severe foetal anaemia. Intrauterine transfusion with erythrocytes significantly improves foetal outcome. Despite a successful transfusion procedure, long-term neurodevelopment may be affected, and developmental follow up is advised.


Asunto(s)
Muerte Fetal , Infecciones por Parvoviridae/diagnóstico , Parvovirus B19 Humano , Complicaciones Infecciosas del Embarazo/diagnóstico , Resultado del Embarazo , Adulto , Femenino , Humanos , Hidropesía Fetal/virología , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Infecciones por Parvoviridae/terapia , Infecciones por Parvoviridae/transmisión , Embarazo , Complicaciones Infecciosas del Embarazo/terapia , Diagnóstico Prenatal
12.
Early Hum Dev ; 117: 39-43, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29275071

RESUMEN

AIM: To explore changes in motor and cognitive outcomes in very preterm (VP; gestational age<30weeks) born children between ages five and six years, and to determine whether changes in these outcomes were associated with the use of healthcare therapies and educational provisions. STUDY DESIGN: Single-center observational cohort study. Five-year-old VP born children of a one-year-cohort of our neonatal follow-up program (N=90) were invited for re-assessments at age six. Use of healthcare therapies and educational provisions was registered at ages five and six years. Motor function (Movement Assessment Battery for Children-2 [M-ABC-2]; higher scores indicate better functioning) and IQ (Wechsler Preschool and Primary Scale for Intelligence [WPPSI-III-NL]) were assessed at both ages. RESULTS: Sixty-four VP born children were seen at ages five and at six years. In this year, 61% received healthcare therapies and/or educational provisions. M-ABC-2 scores of VP born children who received healthcare therapy and/or educational provisions were significantly higher (M=8.9 [SD=3.2]) at age six years than at age five years (M=7.5 [SD=3.3]); p<0.00). M-ABC-2 scores remained stable in the average range in VP born children without any support. IQ scores remained stable irrespective of received support. CONCLUSIONS: Improvements in motor outcomes are associated with the use of healthcare therapies and/or educational support between ages five and six years in VP born children. Future studies need to determine the efficacy of existing interventions, and to develop tailored interventions to support VP born children in the transfer period from preschool to primary education.


Asunto(s)
Intervención Educativa Precoz/métodos , Educación Especial/métodos , Recien Nacido Extremadamente Prematuro/crecimiento & desarrollo , Niño , Desarrollo Infantil , Cognición , Femenino , Humanos , Recién Nacido , Masculino , Destreza Motora , Logopedia/métodos
13.
Accid Anal Prev ; 120: 270-280, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30176523

RESUMEN

Research indicates that crashes between a cyclist and a car often occur even when the cyclist must have seen the approaching car, suggesting the importance of hazard anticipation skills. This study aimed to analyze cyclists' eye movements and crossing judgments while approaching an intersection at different speeds. Thirty-six participants watched animated video clips with a car approaching an uncontrolled four-way intersection and continuously indicated whether they would cross the intersection first. We varied (1) car approach scenario (passing, colliding, stopping), (2) traffic complexity (one or two approaching cars), and (3) cyclist's approach speed (15, 25, or 35 km/h). Results showed that participants looked at the approaching car when it was relevant to the task of crossing the intersection and posed an imminent hazard, and they directed less attention to the car after it had stopped or passed the intersection. Traffic complexity resulted in divided attention between the two cars, but participants retained most visual attention to the car that came from the right and had right of way. Effects of cycling speed on cyclists' gaze behavior and crossing judgments were small to moderate. In conclusion, cyclists' visual focus and crossing judgments are governed by situational factors (i.e., objects with priority and future collision potential), whereas cycling speed does not have substantial effects on eye movements and crossing judgments.


Asunto(s)
Accidentes de Tránsito/psicología , Anticipación Psicológica/fisiología , Atención/fisiología , Ciclismo/psicología , Movimientos Oculares/fisiología , Juicio/fisiología , Adolescente , Adulto , Conducción de Automóvil , Femenino , Humanos , Masculino , Países Bajos , Grabación en Video , Adulto Joven
14.
Clin Pharmacol Ther ; 103(3): 458-467, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28555724

RESUMEN

The pharmacokinetics (PK) of amoxicillin in asphyxiated newborns undergoing moderate hypothermia were quantified using prospective data (N = 125). The population PK was described by a 2-compartment model with a priori birthweight (BW) based allometric scaling. Significant correlations were observed between clearance (Cl) and postnatal age (PNA), gestational age (GA), body temperature (TEMP), and urine output (UO). For a typical patient with GA 40 weeks, BW 3,000 g, 2 days PNA (i.e., TEMP 33.5°C), and normal UO, Cl was 0.26 L/h (interindividual variability (IIV) 41.9%) and volume of distribution of the central compartment was 0.34 L/kg (IIV of 114.6%). For this patient, Cl increased to 0.41 L/h at PNA 5 days and TEMP 37.0°C. The respective contributions of both covariates were 23% and 27%. Based on Monte Carlo simulations we recommend 50 and 75 mg/kg/24h amoxicillin in three doses for patients with GA 36-37 and 38-42 weeks, respectively.


Asunto(s)
Amoxicilina/farmacocinética , Antibacterianos/farmacocinética , Hipotermia/metabolismo , Envejecimiento/metabolismo , Algoritmos , Amoxicilina/administración & dosificación , Antibacterianos/administración & dosificación , Peso al Nacer , Temperatura Corporal , Estudios de Cohortes , Simulación por Computador , Femenino , Edad Gestacional , Humanos , Recién Nacido , Masculino , Método de Montecarlo , Estudios Prospectivos , Urodinámica
15.
J Craniomaxillofac Surg ; 43(10): 2158-67, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26596360

RESUMEN

PURPOSE: The aims of this study were to investigate the effectiveness of cone beam computed tomography (CBCT) compared to panoramic radiography (PR), prior to mandibular third molar removal, in reducing patient morbidity, and to identify risk factors associated with inferior alveolar nerve (IAN) injury. MATERIAL AND METHODS: This multicentre, randomised, controlled trial was performed at three centres in the Netherlands. Adults with an increased risk for IAN injury, as diagnosed from PR, were included in the study. In one arm of the study, patients underwent an additional CBCT prior to third molar surgery. In a second arm of the study, no additional radiographs were acquired. The primary outcome measure was the number of patient-reported altered sensations 1 week after surgery. As secondary outcome measures, the number of patients with objective IAN injury, with long-term (>6 months) IAN injury, the occurrence of other postoperative complications, the Oral Health Related Quality of Life-14 (OHIP-14) questionnaire responses, postoperative pain (visual analogue scale score), duration of surgery, number of emergency visits, and number of missed days of work or study were scored. RESULTS: A total of 268 patients with 320 mandibular third molars were analysed according to the intention-to-treat principle. The overall incidence of IAN injury 1 week after surgery was 6.3%. No significant differences between CBCT and PR for temporary IAN injury (p = 0.64) and all other secondary outcomes were registered. A lingual position of the mandibular canal (MC) and narrowing, in which the diameter of the MC lumen was decreased at the contact area between the MC and the roots, were significant risk factors for temporary IAN injury. CONCLUSION: Although CBCT is a valuable diagnostic adjunct for identification of an increased risk for IAN injury, the use of CBCT does not translate into a reduction of IAN injury and other postoperative complications, after removal of the complete mandibular third molar. In these selected cases of a high risk for IAN injury, an alternative strategy, such as monitoring or a coronectomy, might be more appropriate. (http://clinicaltrials.gov, NCT02071030).


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Tercer Molar/cirugía , Extracción Dental/métodos , Humanos , Países Bajos , Calidad de Vida , Radiografía Panorámica/métodos , Diente Impactado/cirugía , Traumatismos del Nervio Trigémino/epidemiología , Traumatismos del Nervio Trigémino/etiología , Traumatismos del Nervio Trigémino/prevención & control
16.
Clin Chim Acta ; 225(1): 29-42, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8033352

RESUMEN

A GC-MS determination of urea in serum or spent dialysate is described, using 13C15N2-labelled urea and assaying the area ratio of labelled to natural urea by mass fragmentographic monitoring of fragments m/e 153 and 156, after its eventual conversion into the trimethylsilylether-derivative of 2-hydroxypyrimidine. The procedure can be successfully applied in the follow-up of the disappearance of labelled urea in serum after intravenous injection in man, enabling kinetic parameters of urea to be established, e.g. for purposes of studying the effectiveness of dialysis procedures. Furthermore the method can be used for validation of routine methods for measuring urea in other fluids, in particular dialysate. Examples are given of both applications of the GC-MS method described.


Asunto(s)
Urea/análisis , Urea/sangre , Calibración , Isótopos de Carbono , Diálisis , Cromatografía de Gases y Espectrometría de Masas , Humanos , Marcaje Isotópico , Cinética , Masculino , Persona de Mediana Edad , Isótopos de Nitrógeno , Reproducibilidad de los Resultados
17.
Rev Sci Instrum ; 83(7): 073113, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22852677

RESUMEN

A technological milestone for experiments employing transition edge sensor bolometers operating at sub-Kelvin temperature is the deployment of detector arrays with 100s-1000s of bolometers. One key technology for such arrays is readout multiplexing: the ability to read out many sensors simultaneously on the same set of wires. This paper describes a frequency-domain multiplexed readout system which has been developed for and deployed on the APEX-SZ and South Pole Telescope millimeter wavelength receivers. In this system, the detector array is divided into modules of seven detectors, and each bolometer within the module is biased with a unique ∼MHz sinusoidal carrier such that the individual bolometer signals are well separated in frequency space. The currents from all bolometers in a module are summed together and pre-amplified with superconducting quantum interference devices operating at 4 K. Room temperature electronics demodulate the carriers to recover the bolometer signals, which are digitized separately and stored to disk. This readout system contributes little noise relative to the detectors themselves, is remarkably insensitive to unwanted microphonic excitations, and provides a technology pathway to multiplexing larger numbers of sensors.

18.
Q J Nucl Med Mol Imaging ; 54(5): 543-52, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20927021

RESUMEN

Radiotherapy is one of the corner stone treatments for patients with prostate cancer. Especially for locally advanced tumors radiotherapy +/- adjuvant androgen deprivation treatment is standard of care. This brings up the need for accurate assessment of extra prostatic tumor growth and/or the presence of nodal metastases for selection of the optimal radiation dose and treatment volume. Morphological imaging like transrectal ultra sound, computed tomography (CT) and magnetic resonance imaging (MRI) are routinely used but are limited in their accuracy in detecting extra prostatic extension and nodal metastases. In this article we present a structured review of the literature on positron emission tomography (PET)/CT and radiotherapy in prostate cancer patients with emphasis on: 1) the pretreatment assessment of extra prostatic tumor extension, nodal and distant metastases; 2) the intraprostatic tumor characterization and radiotherapy treatment planning; and 3) treatment evaluation and the use of PET/CT in guidance of salvage treatment. PET/CT is not an appropriate imaging technique for accurate T-staging of prostate cancer prior to radiotherapy. Although macroscopic disease beyond the prostatic capsule and into the periprostatic fat or in seminal vesicle is often accurately detected, the microscopic extension of prostate cancer remains undetected. Choline PET/CT holds a great potential as a single step diagnostic procedure of lymph nodes and skeleton, which could facilitate radiotherapy treatment planning. At present the use of PET/CT for treatment planning in radiotherapy is still experimental. Choline PET based tumor delineation is not yet standardized and different segmentation-algorithms are under study. However, dose escalation using dose-painting is feasible with only limited increases of the doses to the bladder and rectum wall. PET/CT using either acetate or choline is able to detect recurrent prostate cancer after radiotherapy but stratification of patients for any local salvage treatment has not been addressed in the current literature.


Asunto(s)
Tomografía de Emisión de Positrones/métodos , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/radioterapia , Radioterapia/métodos , Tomografía Computarizada por Rayos X/métodos , Humanos , Masculino , Metástasis de la Neoplasia , Neoplasias de la Próstata/patología , Planificación de la Radioterapia Asistida por Computador
19.
Acta Paediatr ; 92(12): 1491-3, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14971806

RESUMEN

UNLABELLED: Isolated submandibular suppurative sialadenitis is extremely rare in newborn infants and is associated with prematurity and prolonged gavage feeding. This report describes a premature infant who developed a life-threatening airway obstruction due to suppurative submandibular sialadenitis. The diagnosis was made on clinical grounds and confirmed by ultrasonography. Staphylococcus aureus was grown from the pus expressed from the Wharton's duct orifice. Upper airway obstruction and respiratory failure were managed with intubation and mechanical ventilation, and the sialadenitis resolved quickly and completely with flucloxacillin treatment. Possible causes of sialadenitis include dehydration, decreased saliva flow and stasis during gavage feeding, duct obstruction by stones and direct bacterial inoculation. Ultrasonography is the diagnostic imaging of choice to exclude congenital tumours, lymphadenitis, congenital malformations of the Wharton's duct or the gland itself, and subcutaneous fat necrosis. CONCLUSION: Early diagnosis and antibiotic treatment of suppurative submandibular sialadenitis may prevent complications such as abscess formation, septicaemia and respiratory failure.


Asunto(s)
Ceftazidima/análogos & derivados , Enfermedades del Prematuro , Sialadenitis , Infecciones Estafilocócicas , Ceftazidima/uso terapéutico , Humanos , Recién Nacido , Enfermedades del Prematuro/diagnóstico , Enfermedades del Prematuro/tratamiento farmacológico , Masculino , Monobactamas/uso terapéutico , Sialadenitis/diagnóstico , Sialadenitis/tratamiento farmacológico , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/tratamiento farmacológico , Supuración , Vancomicina/uso terapéutico
20.
Clin Chem ; 33(12): 2164-70, 1987 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3690835

RESUMEN

While determining reference values for porphyrins in feces as measured by liquid chromatography, we observed strong fluctuations in fecal porphyrin contents. To explain these fluctuations, we selectively suppressed the intestinal flora of healthy persons. Suppression of aerobic flora had no effect on fecal porphyrin excretions, whereas suppression of anaerobic flora completely inhibited the transformation of protoporphyrin to pempto- and deuteroporphyrin for as long as five days after stopping medication. During this latter, the conversion to mesoporphyrin was clearly increased in one person and in others partly affected or decreased. During complete suppression of flora for prolonged periods, the production of proto- and coproporphyrins was decreased and deutero-, pempto-, and mesoporphyrins were absent. We conclude that the nature of fecal porphyrins is mostly affected by action of anaerobic bacteria, different kinds of bacteria having different effects. Some, like aerobic Gram-negative bacteria, have little or no effect on porphyrins; some cause production of mesoporphyrin; some promote a conversion to pempto- and deuteroporphyrin; and some mainly cause production of copro- and protoporphyrin. We give examples in which normal to slightly increased excretions of fecal porphyrin do not exclude a diagnosis of porphyria, and relatively high concentrations do not confirm one.


Asunto(s)
Bacterias/metabolismo , Heces/análisis , Porfirinas/metabolismo , Cromatografía Líquida de Alta Presión , Ácidos Grasos Volátiles/análisis , Heces/microbiología , Humanos , Porfirias/metabolismo , Porfirinas/análisis , Valores de Referencia
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