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1.
Support Care Cancer ; 29(5): 2771-2775, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32990784

RESUMO

BACKGROUND: Selecting study endpoints in prospective cancer cachexia trials remains poorly defined. The aim of this study was to further evaluate associations in changes in weight, body composition, functional outcomes, and patient-reported outcomes (PROs) in patients with metastatic cancer. METHODS: We completed a 2-year (2016-2018) observational study in patients with metastatic solid cancer and ECOG performance status 0 to 2 while receiving chemotherapy and/or immunotherapy. We completed assessments at study enrollment and 3 months from enrollment. We analyzed longitudinal changes in weight and body composition using validated methods. Functional assessments included the 6-Min Walk Test, Timed Up and Go Test, and Short Physical Performance Battery. PROs included the Functional Assessment of Anorexia/Cachexia Therapy and Functional Assessment of Cancer Therapy Fatigue. We analyzed changes in body composition and functional assessment using paired t tests. Additionally, we utilized linear regression models to assess relationships between changes in body composition and function outcomes and PROs, adjusting for age and sex. RESULTS: A total of 57 patients completed baseline assessments, but 19 patients did not complete 3-month assessments (5 died, 1 hospice, 13 withdrew). Of the 38 patients with complete data, the mean age was 61.8 years and 47% were female. Metastatic cancer types included 71% gastrointestinal, 13% lung, and 8% gynecologic. Half received chemotherapy, 16% immunotherapy, and 34% a combination. From enrollment to 3 months, we did not observe a change in weight or skeletal muscle but did find an increase in total adipose tissue (16.9 ± 52.4 cm2, 95% CI - 33.79-0.63; p = 0.059; ~ 1.5 pounds). We did not observe any association with changes in weight with any functional outcomes or PROs. However, greater losses in skeletal muscle were associated with greater declines in physical function (6-Min Walk Test [B = 0.04, p = 0.01], Short Physical Performance Battery [B = 2.44, p < 0.01]). CONCLUSIONS: Patients with metastatic cancer receiving cancer-directed therapy may not experience a change in body weight. However, we found an association between losses in skeletal muscle and greater declines in physical function. Therefore, when selecting study endpoints, prospective cancer cachexia studies may consider selecting changes in body composition over weight.


Assuntos
Caquexia/etiologia , Segunda Neoplasia Primária/diagnóstico por imagem , Neoplasias/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
BMC Pediatr ; 21(1): 12, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407279

RESUMO

BACKGROUND: Globally, 15 million neonates are born prematurely every year, over half in low income countries (LICs). Premature and low birth weight neonates have a higher risk of intraventricular haemorrhage (IVH). There are minimal data regarding IVH in sub-Saharan Africa. This study aimed to examine the incidence, severity and timing of and modifiable risk factors for IVH amongst low-birth-weight neonates in Uganda. METHODS: This is a prospective cohort study of neonates with birthweights of ≤2000 g admitted to a neonatal unit (NU) in a regional referral hospital in eastern Uganda. Maternal data were collected from interviews and medical records. Neonates had cranial ultrasound (cUS) scans on the day of recruitment and days 3, 7 and 28 after birth. Risk factors were tabulated and are presented alongside odds ratios (ORs) and adjusted odds ratios (aORs) for IVH incidence. Outcomes included incidence, timing and severity of IVH and 28-day survival. RESULTS: Overall, 120 neonates were recruited. IVH was reported in 34.2% of neonates; 19.2% had low grade (Papile grades 1-2) and 15% had high grade (Papile grades 3-4). Almost all IVH (90.2%) occurred by day 7, including 88.9% of high grade IVH. Of those with known outcomes, 70.4% (81/115) were alive on day 28 and survival was not associated with IVH. We found that vaginal delivery, gestational age (GA) < 32 weeks and resuscitation in the NU increased the odds of IVH. Of the 6 neonates who received 2 doses of antenatal steroids, none had IVH. CONCLUSION: In this resource limited NU in eastern Uganda, more than a third of neonates born weighing ≤2000 g had an IVH and the majority of these occurred by day 7. We found that vaginal birth, earlier gestation and need for resuscitation after admission to the NU increased the risk of IVH. This study had a high rate of SGA neonates and the risk factors and relationship of these factors with IVH in this setting needs further investigation. The role of antenatal steroids in the prevention of IVH in LICs also needs urgent exploration.


Assuntos
Recém-Nascido de Baixo Peso , Doenças do Prematuro , Peso ao Nascer , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/etiologia , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Doenças do Prematuro/epidemiologia , Doenças do Prematuro/etiologia , Gravidez , Estudos Prospectivos , Fatores de Risco , Uganda/epidemiologia
3.
Adv Exp Med Biol ; 876: 377-382, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26782235

RESUMO

The brain of preterm infants is the most vulnerable organ and can be severely injured by cerebral ischemia. We are working on a near-infrared imager to early detect cerebral ischemia. During imaging of the brain, movements of the newborn infants are inevitable and the near-infrared sensor has to be able to function on irregular geometries. Our aim is to determine the robustness of the near-infrared image reconstruction to small variations of the source and detector locations. In analytical and numerical simulations, the error estimations for a homogeneous medium agree well. The worst case estimates of errors in reduced scattering and absorption coefficient for distances of r=40 mm are acceptable for a single source-detector pair. The optical properties of an inhomogeneity representing an ischemia are reconstructed correctly within a homogeneous medium, if the error in placement is random.


Assuntos
Encéfalo/metabolismo , Processamento de Imagem Assistida por Computador , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Humanos , Recém-Nascido
4.
Adv Exp Med Biol ; 876: 111-120, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26782202

RESUMO

We present a computational model of metabolism in the preterm neonatal brain. The model has the capacity to mimic haemodynamic and metabolic changes during functional activation and simulate functional near-infrared spectroscopy (fNIRS) data. As an initial test of the model's efficacy, we simulate data obtained from published studies investigating functional activity in preterm neonates. In addition we simulated recently collected data from preterm neonates during visual activation. The model is well able to predict the haemodynamic and metabolic changes from these observations. In particular, we found that changes in cerebral blood flow and blood pressure may account for the observed variability of the magnitude and sign of stimulus-evoked haemodynamic changes reported in preterm infants.


Assuntos
Encéfalo/metabolismo , Recém-Nascido Prematuro/metabolismo , Oxigênio/metabolismo , Circulação Cerebrovascular , Simulação por Computador , Hemodinâmica , Humanos , Recém-Nascido
5.
Phys Rev Lett ; 112(17): 171303, 2014 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-24836233

RESUMO

This Letter details a measurement of the ionization yield (Q(y)) of 6.7 keV(40)Ar atoms stopping in a liquid argon detector. The Q(y) of 3.6-6.3 detected e(-)/keV, for applied electric fields in the range 240-2130 V/cm, is encouraging for the use of this detector medium to search for the signals from hypothetical dark matter particle interactions and from coherent elastic neutrino-nucleus scattering. A significant dependence of Q(y) on the applied electric field is observed and explained in the context of ion recombination.

6.
Phys Rev Lett ; 111(5): 052501, 2013 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-23952390

RESUMO

Neutron time-of-flight spectra from inertial confinement fusion experiments with tritium-filled targets have been measured at the National Ignition Facility. These spectra represent a significant improvement in energy resolution and statistics over previous measurements, and afford the first definitive observation of a peak resulting from sequential decay through the ground state of (5)He at low reaction energies E(c.m.) 100

7.
J Neuroradiol ; 38(5): 291-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21396715

RESUMO

BACKGROUND: Cranial ultrasound (cUS) findings help doctors in the clinical management of preterm infants and in their discussion with parents regarding prediction of outcome. cUS is often used as outcome measure in clinical research studies. Accurate cUS performance and interpretation is therefore required. AIMS: The aims of this study were (i) to assess the interobserver variability in cUS interpretation, and (ii) to evaluate whether level of cUS expertise influences the interobserver variability. METHODS: Fifty-eight cUS image series of preterm infants born below 32 weeks of gestation collected within the Swiss Neonatal Network were sent to 27 observers for reviewing. Observers were grouped into radiologists, experienced neonatologists and less experienced neonatologists. Agreement between observers was calculated using Kappa statistics. RESULTS: When cystic periventricular leukomalacia, intraventricular haemorrhage and periventricular haemorrhagic infarction were combined to one outcome, agreement among all observers was moderate. When divided into subgroups, kappa for the combined outcome was 0.7 for experienced neonatologists, 0.67 for radiologists and 0.53 for inexperienced neonatologists. Marked difference in interobserver agreement between experienced neonatologists and radiologists could be found for haemorrhagic periventricular ifraction (HPI). CONCLUSIONS: Our results suggest that interobserver agreement for interpretation of cUS varies from poor to good varying with the type of abnormality and level of expertise, suggesting that widespread structured training should be made available to improve the performance and interpretation of cUS.


Assuntos
Encefalopatias/diagnóstico por imagem , Ecoencefalografia/métodos , Recém-Nascido Prematuro , Feminino , Humanos , Recém-Nascido , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Suíça
8.
J Matern Fetal Neonatal Med ; 34(7): 1020-1027, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31117854

RESUMO

OBJECTIVE: Neonates exposed to perinatal insults typically present with hypoxic ischemic encephalopathy (HIE). The aim of our study was to analyze the association between known risk factors for HIE and the severity of encephalopathy after birth and neurological outcome in neonates during the first 4 d of life. METHODS: Retrospective cohort study including 174 neonates registered between 2011 and 2013 in the National Asphyxia and Cooling Register of Switzerland. RESULTS: None of the studied perinatal risk factors is associated with the severity of encephalopathy after birth. Fetal distress during labor (OR, 2.06; 95% CI, 1.02-4.25, p = .049) and neonatal head circumference (HC) above 10th percentile (p10) at birth (OR, 1.33; 95% CI, 1.05-1.69, p = .02) were associated with neurological benefit in the univariate analysis. Fetal distress on maternal admission for delivery was the only risk factor for neurological harm in the univariate (OR, 0.26; 95% CI, 0.12-0.57, p < .01) and the multivariate analysis (OR, 0.15; 95% CI, 0.04-0.67, p = .013). We identified two different patient scenarios: the probability for neurological benefit during the first 4 d of life was only 20% in neonates with the combination of all the following risk factors (gestational age >41 weeks, chorioamnionitis, fetal distress on maternal admission for delivery, fetal distress during labor, sentinel events during labor, HC below 10th percentile), whereas in the absence of these risk factors the probability for neurological benefit increased to 80%. CONCLUSIONS: We identified a constellation of risk factors that influence neurological outcome in neonates with HIE during the first 4 d of life. These findings may help clinicians to counsel parents during the early neonatal period. (ClinicalTrials.gov NCT02800018).


Assuntos
Hipóxia-Isquemia Encefálica , Feminino , Sofrimento Fetal , Humanos , Hipóxia-Isquemia Encefálica/complicações , Hipóxia-Isquemia Encefálica/epidemiologia , Lactente , Recém-Nascido , Gravidez , Estudos Retrospectivos , Fatores de Risco , Suíça/epidemiologia
9.
AJNR Am J Neuroradiol ; 42(11): 2034-2039, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34674999

RESUMO

BACKGROUND AND PURPOSE: A uniform description of brain MR imaging findings in infants with severe congenital heart disease to assess risk factors, predict outcome, and compare centers is lacking. Our objective was to uniformly describe the spectrum of perioperative brain MR imaging findings in infants with congenital heart disease. MATERIALS AND METHODS: Prospective observational studies were performed at 3 European centers between 2009 and 2019. Brain MR imaging was performed preoperatively and/or postoperatively in infants with transposition of the great arteries, single-ventricle physiology, or left ventricular outflow tract obstruction undergoing cardiac surgery within the first 6 weeks of life. Brain injury was assessed on T1, T2, DWI, SWI, and MRV. A subsample of images was assessed jointly to reach a consensus. RESULTS: A total of 348 MR imaging scans (180 preoperatively, 168 postoperatively, 146 pre- and postoperatively) were obtained in 202 infants. Preoperative, new postoperative, and cumulative postoperative white matter injury was identified in 25%, 30%, and 36%; arterial ischemic stroke, in 6%, 10%, and 14%; hypoxic-ischemic watershed injury in 2%, 1%, and 1%; intraparenchymal cerebral hemorrhage, in 0%, 4%, and 5%; cerebellar hemorrhage, in 6%, 2%, and 6%; intraventricular hemorrhage, in 14%, 6%, and 13%; subdural hemorrhage, in 29%, 17%, and 29%; and cerebral sinovenous thrombosis, in 0%, 10%, and 10%, respectively. CONCLUSIONS: A broad spectrum of perioperative brain MR imaging findings was found in infants with severe congenital heart disease. We propose an MR imaging protocol including T1-, T2-, diffusion-, and susceptibility-weighted imaging, and MRV to identify ischemic, hemorrhagic, and thrombotic lesions observed in this patient group.


Assuntos
Cardiopatias Congênitas , Transposição dos Grandes Vasos , Encéfalo/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Imageamento por Ressonância Magnética , Neuroimagem , Transposição dos Grandes Vasos/diagnóstico por imagem , Transposição dos Grandes Vasos/cirurgia
10.
Opt Lett ; 35(3): 354-6, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-20125719

RESUMO

What we believe to be the first demonstration of isotope-specific detection of a low-Z and low density object shielded by a high-Z and high-density material using monoenergetic gamma rays is reported. The isotope-specific detection of LiH shielded by Pb and Al is accomplished using the nuclear resonance fluorescence line of L7i at 478 keV. Resonant photons are produced via laser-based Compton scattering. The detection techniques are general, and the confidence level obtained is shown to be superior to that yielded by conventional x-ray and gamma-ray techniques in these situations.

11.
Phys Rev Lett ; 104(4): 041301, 2010 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-20366699

RESUMO

Axions in the microeV mass range are a plausible cold dark-matter candidate and may be detected by their conversion into microwave photons in a resonant cavity immersed in a static magnetic field. We report the first result from such an axion search using a superconducting first-stage amplifier (SQUID) replacing a conventional GaAs field-effect transistor amplifier. This experiment excludes KSVZ dark-matter axions with masses between 3.3 microeV and 3.53 microeV and sets the stage for a definitive axion search utilizing near quantum-limited SQUID amplifiers.

12.
Phys Rev Lett ; 105(5): 051801, 2010 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-20867906

RESUMO

Scalar fields with a "chameleon" property, in which the effective particle mass is a function of its local environment, are common to many theories beyond the standard model and could be responsible for dark energy. If these fields couple weakly to the photon, they could be detectable through the afterglow effect of photon-chameleon-photon transitions. The ADMX experiment was used in the first chameleon search with a microwave cavity to set a new limit on scalar chameleon-photon coupling ßγ excluding values between 2×10(9) and 5×10(14) for effective chameleon masses between 1.9510 and 1.9525 µeV.

13.
Phys Rev Lett ; 105(17): 171801, 2010 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-21231034

RESUMO

Hidden U(1) gauge symmetries are common to many extensions of the standard model proposed to explain dark matter. The hidden gauge vector bosons of such extensions may mix kinetically with standard model photons, providing a means for electromagnetic power to pass through conducting barriers. The axion dark matter experiment detector was used to search for hidden vector bosons originating in an emitter cavity driven with microwave power. We exclude hidden vector bosons with kinetic couplings χ>3.48×10⁻8 for masses less than 3 µeV. This limit represents an improvement of more than 2 orders of magnitude in sensitivity relative to previous cavity experiments.

14.
Neuroimage Clin ; 22: 101806, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30991614

RESUMO

Periventricular white matter injury is common in very preterm infants and it is associated with long term neurodevelopmental impairments. While evidence supports the protective effects of erythropoetin (EPO) in preventing injury, we currently lack the complete understanding of how EPO affects the emergence and maturation of anatomical brain connectivity and function. In this case-control study, connectomic analysis based on diffusion MRI tractography was applied to evaluate the effect of early high-dose EPO in preterm infants. A whole brain, network-level analysis revealed a sub-network of anatomical brain connections in which connectivity strengths were significantly stronger in the EPO group. This distributed network comprised connections predominantly in the frontal and temporal lobe bilaterally, and the effect of EPO was focused on peripheral and feeder connections of the core structural connectivity network. EPO resulted in a globally increased clustering coefficient, higher global and average local efficiency, while higher strength and increased clustering was found for regions in the frontal lobe and cingulate gyrus. The connectivity network most affected by the EPO treatment showed a steeper increase graph theoretical measures with age compared to the placebo group. Our results demonstrate a weak but widespread effect of EPO on the structural connectivity network and a possible trophic effect of EPO reflected by increasing network segregation, predominantly in local connections.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Eritropoetina/farmacologia , Lactente Extremamente Prematuro , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/diagnóstico por imagem , Fármacos Neuroprotetores/farmacologia , Estudos de Casos e Controles , Eritropoetina/administração & dosagem , Humanos , Recém-Nascido , Fármacos Neuroprotetores/administração & dosagem
15.
Arch Dis Child Fetal Neonatal Ed ; 92(3): F215-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17449856

RESUMO

The aim of this study was to compare postmortem magnetic resonance imaging (MRI) of the renal system with autopsy in perinatal and fetal deaths. 37 deaths were studied and renal abnormalities were found in five of these cases. Postmortem MRI provided information of diagnostic utility comparable to that obtained by autopsy.


Assuntos
Autopsia , Imageamento por Ressonância Magnética , Sistema Urinário/anormalidades , Doenças Urológicas/patologia , Autopsia/métodos , Morte Fetal/patologia , Humanos , Recém-Nascido
17.
J Perinatol ; 37(9): 1032-1037, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28617423

RESUMO

OBJECTIVE: The objective of the study was whether temperature management during therapeutic hypothermia correlates with the severity of brain injury assessed on magnetic resonance imaging in term infants with hypoxic-ischemic encephalopathy. STUDY DESIGN: Prospectively collected register data from the National Asphyxia and Cooling Register of Switzerland were analyzed. RESULT: Fifty-five newborn infants were cooled for 72 h with a target temperature range of 33 to 34 °C. Individual temperature variability (odds ratio (OR) 40.17 (95% confidence interval (CI) 1.37 to 1037.67)) and percentage of temperatures within the target range (OR 0.95 (95% CI 0.90 to 0.98)) were associated with the severity of brain injury seen on magnetic resonance imaging (MRI). Neither the percentage of measured temperatures above (OR 1.08 (95% CI 0.96 to 1.21)) nor below (OR 0.99 (95% CI 0.92 to 1.07) the target range was associated with the severity of brain injury seen on MRI. CONCLUSION: In a national perinatal asphyxia cohort, temperature variability and percentage of temperatures within the target temperature range were associated with the severity of brain injury.


Assuntos
Asfixia Neonatal/terapia , Temperatura Corporal/fisiologia , Hipotermia Induzida/efeitos adversos , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Idade Gestacional , Humanos , Hipotermia Induzida/métodos , Hipóxia-Isquemia Encefálica/etiologia , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Estudos Prospectivos , Sistema de Registros , Ressuscitação/estatística & dados numéricos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo
18.
Early Hum Dev ; 91(12): 739-49, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26386608

RESUMO

BACKGROUND: Newborn neurological examinations have mostly been developed in high-resource settings with cohorts comprising predominantly white Caucasian infants. No comparison has been made with different populations. AIMS: To (i) establish the range of neurological findings in apparently well newborn term Ugandan infants, (ii) compare these findings to published data for equivalent term UK infants and (iii) correlate the neurological findings with perinatal characteristics and cranial ultrasound (cUS) imaging. METHODS: Low-risk term Ugandan infants were recruited from the postnatal ward at Mulago Hospital, Kampala, Uganda. Neurological examination (1) and cUS were performed. The raw data and neurological optimality scores were compared to published data from UK infants (1). Gestational age, postnatal age, sex, maternal parity and HIV status, mode of delivery, birth weight and head circumference were correlated with raw scores. RESULTS: Ugandan infants showed significantly stronger palmar grasp, better auditory and visual orientation, less irritability and less need for consoling but had poorer tone, poorer quality of spontaneous movements and more abnormal signs than UK infants. No correlation was found between raw scores and cUS findings, gestational age, sex, birth weight and head circumference. Significantly fewer Ugandan infants had optimal scores based on the UK data. CONCLUSION: The neurological status of low-risk hospital-born term Ugandan infants differs from that of low-risk UK infants. The study findings have implications for assessing normality in Ugandan infants and raise concerns about the use of this UK "optimality" score in other research settings. Further work is needed to understand fully the reasons for the differences.


Assuntos
Atenção/fisiologia , Força da Mão/fisiologia , Exame Neurológico/métodos , Orientação/fisiologia , Nascimento a Termo , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Uganda , Reino Unido
19.
Rev Sci Instrum ; 86(7): 076105, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26233419

RESUMO

A new radiochemical method for determining deuterium-tritium (DT) fuel and plastic ablator (CH) areal densities (ρR) in high-convergence, cryogenic inertial confinement fusion implosions at the National Ignition Facility is described. It is based on measuring the (198)Au/(196)Au activation ratio using the collected post-shot debris of the Au hohlraum. The Au ratio combined with the independently measured neutron down scatter ratio uniquely determines the areal densities ρR(DT) and ρR(CH) during burn in the context of a simple 1-dimensional capsule model. The results show larger than expected ρR(CH) values, hinting at the presence of cold fuel-ablator mix.

20.
Rev Sci Instrum ; 85(6): 063508, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24985820

RESUMO

We describe a radiochemical measurement of the ratio of isotope concentrations produced in a gold hohlraum surrounding an Inertial Confinement Fusion capsule at the National Ignition Facility (NIF). We relate the ratio of the concentrations of (n,γ) and (n,2n) products in the gold hohlraum matrix to the down-scatter of neutrons in the compressed fuel and, consequently, to the fuel's areal density. The observed ratio of the concentrations of (198m+g)Au and (196g)Au is a performance signature of ablator areal density and the fuel assembly confinement time. We identify the measurement of nuclear cross sections of astrophysical importance as a potential application of the neutrons generated at the NIF.

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