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1.
Nature ; 605(7909): 244-247, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35546195

RESUMO

Bright quasars, powered by accretion onto billion-solar-mass black holes, already existed at the epoch of reionization, when the Universe was 0.5-1 billion years old1. How these black holes formed in such a short time is the subject of debate, particularly as they lie above the correlation between black-hole mass and galaxy dynamical mass2,3 in the local Universe. What slowed down black-hole growth, leading towards the symbiotic growth observed in the local Universe, and when this process started, has hitherto not been known, although black-hole feedback is a likely driver4. Here we report optical and near-infrared observations of a sample of quasars at redshifts 5.8 ≲ z ≲ 6.6. About half of the quasar spectra reveal broad, blueshifted absorption line troughs, tracing black-hole-driven winds with extreme outflow velocities, up to 17% of the speed of light. The fraction of quasars with such outflow winds at z ≳ 5.8 is ≈2.4 times higher than at z ≈ 2-4. We infer that outflows at z ≳ 5.8 inject large amounts of energy into the interstellar medium and suppress nuclear gas accretion, slowing down black-hole growth. The outflow phase may then mark the beginning of substantial black-hole feedback. The red optical colours of outflow quasars at z ≳ 5.8 indeed suggest that these systems are dusty and may be caught during an initial quenching phase of obscured accretion5.

2.
BMC Cancer ; 24(1): 984, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39123197

RESUMO

PURPOSE: Chimeric antigen receptor T-cell (CART) therapy has shown clinical efficacy in refractory and relapsed large B-cell lymphomas, but is associated with serious acute and long-term toxicities. To understand the patient perspective, we measured a patient-reported outcome (PRO), specifically, health-related quality of life (HRQoL), at multiple time points over one year. METHODS: This was a prospective feasibility study of a cohort of patients who were eligible for standard of care CART therapy, tisagenlecleucel. Demographic data and disease characteristics were collected. HRQoL was measured using FACT-Lym at baseline, and months 1, 3, 6 and 12. FACT-Lym includes FACT-G (physical, social, emotional and functional well-being domains), plus a lymphoma subscale. RESULTS: Thirty-four of 35 patients approached, consented to participate. Two of them did not receive their infusion due to progressive disease. 50% were female and median age was 62 (23-77). Twenty-nine patients (91%) completed baseline FACT-Lym and 20 of 21 (95%) eligible patients completed 12-month FACT-Lym. 52% completed all 4 post-baseline FACT-Lym measures. Exploratory analyses for changes in FACT-Lym scores are reported. CONCLUSION: It is feasible to measure longitudinal PROs in patients who receive CART therapy. This study will inform future studies in evaluating the patient perspective on CART therapy.


Assuntos
Estudos de Viabilidade , Imunoterapia Adotiva , Linfoma Difuso de Grandes Células B , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Adulto , Linfoma Difuso de Grandes Células B/terapia , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Estudos Prospectivos , Adulto Jovem , Receptores de Antígenos Quiméricos/uso terapêutico , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos de Linfócitos T/uso terapêutico , Receptores de Antígenos de Linfócitos T/imunologia , Estudos Longitudinais , Recidiva Local de Neoplasia/imunologia , Resultado do Tratamento
3.
Ultrasound Obstet Gynecol ; 62(1): 94-105, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36779229

RESUMO

OBJECTIVES: Congenital hypotonic conditions are rare and heterogeneous, and some are severely debilitating or lethal. Contrary to its prominent postnatal manifestation, the prenatal presentation of hypotonia is frequently subtle, inhibiting prenatal detection. We aimed to characterize the prenatal sonographic manifestation of congenital hypotonia throughout pregnancy, evaluate the yield of diagnostic tests and propose diagnostic models to increase its prenatal detection. METHODS: This was a retrospective observational study of singleton pregnancies with congenital hypotonia, diagnosed either prenatally or immediately after birth, at a single tertiary center between the years 2012 and 2020. Prenatally, hypotonia was diagnosed if a fetus showed sonographic or clinical signs suggestive of hypotonia and had a confirmed underlying genetic condition, or in the absence of a known genetic abnormality if the fetus exhibited multiple prominent signs suggestive of hypotonia. Postnatally, it was diagnosed in neonates displaying reduced muscle tone leading to reduced spontaneous movement, reduced swallowing or feeding difficulty. We reviewed the medical records of pregnant patients carrying fetuses subsequently diagnosed with congenital hypotonia and assessed the yield of ultrasound scans, fetal magnetic resonance imaging, computed tomography and genetic tests. The detection rate of sonographic signs suggesting fetal hypotonia was calculated. The prevalence of non-specific signs, including polyhydramnios, persistent breech presentation, intrauterine growth restriction and maternal perception of reduced fetal movement, were compared between the study group and the local liveborn singleton population. Potential detection rates of different theoretical semiotic diagnostic models, differing in the threshold for referral for a targeted scan, were assessed based on the cohort's data. RESULTS: The study group comprised 26 cases of congenital hypotonia, of which 10 (38.5%) were diagnosed prenatally, and the controls included 95 105 singleton live births, giving a prevalence of congenital hypotonia of 1:3658. Nuchal translucency thickness and the early anomaly scan at 13-17 weeks were normal in all 22 and 23 cases, respectively, in which this was performed. The mid-trimester scan performed at 19-25 weeks was abnormal in four of 24 (16.7%) cases. The overall prenatal detection rate of congenital hypotonic conditions in our cohort was 38.5%. Only cases which underwent a targeted scan were detected and, among the 16 cases which underwent this scan, the prenatal detection rate was 62.5% compared with 0% in pregnancies that did not undergo this scan (P = 0.003). An abnormal genetic diagnosis was obtained in 21 (80.8%) cases using the following modalities: chromosomal microarray analysis (CMA) in two (9.5%), whole-exome sequencing (WES) in 14 (66.7%) and methylation analysis in five (23.8%). CMA was abnormal in 8% (2/25) of the cases and WES detected a causative genetic mutation in 87.5% (14/16) of the cases in which these were performed. Comparison of non-specific signs in the study group with those in the local singleton population showed that hypotonic fetuses had significantly more polyhydramnios (64.0% vs 3.0%, P < 0.0001), persistent breech presentation (58.3% vs 4.2%, P < 0.0001), intrauterine growth restriction (30.8% vs 3.0%, P < 0.0001) and maternal perception of reduced fetal movement (32.0% vs 4.7%, P < 0.0001). Prenatally, the most commonly detected signs supporting a diagnosis of hypotonia were structural anomaly (62.5%, 10/16), reduced fetal movement (46.7%, 7/15), joint contractures (46.7%, 7/15) and undescended testes ≥ 30 weeks (42.9%, 3/7 males). Proposed diagnostic strategies that involved performing a targeted scan for a single non-specific ultrasound sign or two such signs, and then carrying out a comprehensive genetic evaluation for any additional sign, offered theoretical detection rates in our cohort of 88.5% and 57.7%, respectively. CONCLUSIONS: Congenital hypotonic conditions are rare and infrequently detected prenatally. Sonographic signs are visible from the late second trimester. A targeted scan increases prenatal detection significantly. Comprehensive genetic testing, especially WES, is the cornerstone of diagnosis in congenital hypotonia. Theoretical diagnostic models which may increase prenatal detection are provided. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Apresentação Pélvica , Poli-Hidrâmnios , Gravidez , Masculino , Feminino , Recém-Nascido , Humanos , Hipotonia Muscular/diagnóstico por imagem , Hipotonia Muscular/genética , Retardo do Crescimento Fetal , Ultrassonografia Pré-Natal/métodos , Feto/diagnóstico por imagem , Estudos Retrospectivos , Diagnóstico Pré-Natal/métodos , Estudos Observacionais como Assunto
4.
Teach Learn Med ; : 1-7, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553839

RESUMO

Issue: Health professions education (HPE) is intimately linked with teaching and learning in the clinical environment. While the value of authentic clinical experiences is acknowledged, whether learning actually occurs is to a large extent dependent on students' behaviors and attitudes. The kinds of student behaviors and attitudes that are necessary to optimize learning in the clinical environment thus becomes relevant. Evidence: Tips and recommendations to maximize clinical learning in a variety of settings have been well documented. There is, however, a dearth of literature which takes a narrative-based praxis approach focused on resource-constrained environments. We developed this praxis-orientated article as a means to translate the available literature and theory into a simple, practical guide, focused on optimizing clinical learning from a student perspective, remaining cognizant of the particular challenges present in a resource-constrained setting. Implications: Based on the resource-constrained environments our students are exposed to, we outline the following six key aspects: student-driven learning, integration into the community of practice, student engagement, empathy, interprofessional learning opportunities, and feedback for learning. These aspects provide useful pointers for students in general. Furthermore, exploration into what strategies students may utilize in resource-constrained clinical contexts is addressed.

5.
NMR Biomed ; 35(5): e4664, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34904305

RESUMO

The objective of the current study was to investigate the feasibility of quantitative 3D ultrashort echo time (UTE)-based biomarkers in detecting proteoglycan (PG) loss and collagen degradation in human cartilage. A total of 104 cartilage samples were harvested for a trypsin digestion study (n = 44), and a sequential trypsin and collagenase digestion study (n = 60), respectively. Forty-four cartilage samples were randomly divided into a trypsin digestion group (tryp group) and a control group (phosphate-buffered saline [PBS] group) (n = 22 for each group) for the trypsin digestion experiment. The remaining 60 cartilage samples were divided equally into four groups (n = 15 for each group) for sequential trypsin and collagenase digestion, including PBS + Tris (incubated in PBS, then Tris buffer solution), PBS + 30 U col (incubated in PBS, then 30 U/ml collagenase [30 U col] with Tris buffer solution), tryp + 30 U col (incubated in trypsin solution, then 30 U/ml collagenase with Tris buffer solution), and tryp + Tris (incubated in trypsin solution, then Tris buffer solution). The 3D UTE-based MRI biomarkers included T1 , multiecho T2 *, adiabatic T1ρ (AdiabT1ρ ), magnetization transfer ratio (MTR), and modeling of macromolecular proton fraction (MMF). For each cartilage sample, UTE-based biomarkers (T1 , T2 *, AdiabT1ρ , MTR, and MMF) and sample weight were evaluated before and after treatment. PG and hydroxyproline assays were performed. Differences between groups and correlations were assessed. All the evaluated biomarkers were able to differentiate between healthy and degenerated cartilage in the trypsin digestion experiment, but only T1 and AdiabT1ρ were significantly correlated with the PG concentration in the digestion solution (p = 0.004 and p = 0.0001, respectively). In the sequential digestion experiment, no significant differences were found for T1 and AdiabT1ρ values between the PBS + Tris and PBS + 30 U col groups (p = 0.627 and p = 0.877, respectively), but T1 and AdiabT1ρ values increased significantly in the tryp + Tris (p = 0.031 and p = 0.024, respectively) and tryp + 30 U col groups (both p < 0.0001). Significant decreases in MMF and MTR were found in the tryp + 30 U col group compared with the PBS + Tris group (p = 0.002 and p = 0.001, respectively). It was concluded that AdiabT1ρ and T1 have the potential for detecting PG loss, while MMF and MTR are promising for the detection of collagen degradation in articular cartilage, which could facilitate earlier, noninvasive diagnosis of osteoarthritis.


Assuntos
Cartilagem Articular , Biomarcadores , Cartilagem Articular/diagnóstico por imagem , Colágeno , Colagenases , Estudos de Viabilidade , Humanos , Imageamento Tridimensional , Substâncias Macromoleculares , Imageamento por Ressonância Magnética , Proteoglicanas , Trometamina , Tripsina
6.
Osteoarthritis Cartilage ; 29(1): 59-67, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33246159

RESUMO

OBJECTIVES: Knee osteoarthritis (KOA) progression is frequently monitored by calculating the change in knee joint space width (JSW) measurements. Such differences are small and sensitive to measurement error. We aimed to assess the utility of two alternative statistical modelling methods for monitoring KOA. MATERIAL AND METHODS: We used JSW on radiographs from both the control arm of the Strontium Ranelate Efficacy in Knee Osteoarthritis trial (SEKOIA), a 3-year multicentre, double-blind, placebo-controlled phase three trial, and the Osteoarthritis Initiative (OAI), an open-access longitudinal dataset from the USA comprising participants followed over 8 years. Individual estimates of annualised change obtained from frequentist linear mixed effect (LME) and Bayesian hierarchical modelling, were compared with annualised crude change, and the association of these parameters with change in WOMAC pain was examined. RESULTS: Mean annualised JSW changes were comparable for all estimates, a reduction of around 0.14 mm/y in SEKOIA and 0.08 mm/y in OAI. The standard deviation (SD) of change estimates was lower with LME and Bayesian modelling than crude change (SEKOIA SD = 0.12, 0.12 and 0.21 respectively; OAI SD = 0.08, 0.08 and 0.11 respectively). Estimates from LME and Bayesian modelling were statistically significant predictors of change in pain in SEKOIA (LME P-value = 0.04, Bayes P-value = 0.04), while crude change did not predict change in pain (P-value = 0.10). CONCLUSIONS: Implementation of LME or Bayesian modelling in clinical trials and epidemiological studies, would reduce sample sizes by enabling all study participants to be included in analysis regardless of incomplete follow up, and precision of change estimates would improve. They provide increased power to detect associations with other measures.


Assuntos
Articulação do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/diagnóstico por imagem , Idoso , Teorema de Bayes , Progressão da Doença , Feminino , Humanos , Articulação do Joelho/patologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Osteoartrite do Joelho/fisiopatologia , Avaliação de Resultados em Cuidados de Saúde
7.
BJOG ; 128(9): 1511-1516, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33978295

RESUMO

OBJECTIVE: To evaluate whether the adnexal twist degree is related to torsion recurrence and whether there is a dose-dependent correlation. DESIGN: A retrospective cohort study. SETTING: Single tertiary medical centre. POPULATION: The study includes non-pregnant patients operated, for the first time, for adnexal torsion, between 2011 and 2018. METHODS: Information regarding the degree of adnexal twist was collected from surgical reports. Recurrence was identified using a computerised database and ascertained via telephone with a response rate of 87.2% (253/290). MAIN OUTCOME MEASURES: Adnexal torsion recurrence rate. RESULTS: A total of 182 women who had undergone laparoscopic detorsion met the inclusion criteria. Twenty-two had torsion recurrence (12.1%). Adnexal twist degree in the primary event was associated with a higher recurrence risk: 4.3% of women with twist degree ≤360 (n = 3/70), 14.5% of women with twist degree of 361-720 (n = 9/62) and 20% of women with twist degree >720 (n = 10/50) (P = 0.03). The median twist degree was 540 (interquartile range [IQR] 360-855) and 720 (IQR 675-1080) degrees in the control and study groups, respectively (P = 0.005). Additional possibly associated factors for recurrence were evaluated. Age emerged as a possible risk factor, with a median age of 19 years in the recurrence group (IQR 14-27 years) versus 28.5 (IQR 19-36 years) in the non-recurrence group (P < 0.01). Logistic regression analysis revealed that together with age, adnexal twist degree remained significantly associated with torsion recurrence (odds ratio [OR] 1.98, 95% CI 1.09-3.61; P = 0.02). CONCLUSION: Adnexal twist degree was found to be positively associated with the risk of torsion recurrence. TWEETABLE ABSTRACT: Adnexal twist degree was found to be positively associated with the risk of torsion recurrence.


Assuntos
Doenças dos Anexos/cirurgia , Anormalidade Torcional/cirurgia , Adulto , Feminino , Humanos , Recidiva , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
8.
Thorac Cardiovasc Surg ; 69(S 03): e21-e31, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33638137

RESUMO

BACKGROUND: Based on a quality assurance initiative of the German Society for Thoracic and Cardiovascular Surgery (DGTHG) and the German Society for Pediatric Cardiology and Congenital Heart Defects (DGPK), a voluntary registry was founded for assessment of treatment and outcomes of patients with congenital heart disease in Germany. This evaluation by the German Registry for cardiac operations and interventions in patients with congenital heart disease reports the data and the outcome over a 6-year period in patients undergoing invasive treatment. METHODS: This real-world database collects clinical characteristics, in-hospital complications, and medium-term outcome of patients who underwent cardiac surgical and interventional procedures within the prospective, all-comers registry. Patients were followed-up for up to 90 days. RESULTS: In the period from 2013 to 2018, a total of 35,730 patients, 39,875 cases, respectively 46,700 procedures were included at up to 31 German institutions. The cases could be subcategorized according to the treatment intention into 21,027 (52.7%) isolated operations, 17,259 (43.3%) isolated interventions, and 1,589 (4.0%) with multiple procedures. Of these, 4,708 (11.8%) were performed in neonates, 10,047 (25.2%) in infants, 19,351 (48.5%) in children of 1 to 18 years, and 5,769 (14.5%) in adults. Also, 15,845 (33.9%) cases could be allocated to so-called index procedures which underwent a more detailed evaluation to enable meaningful comparability. The mean unadjusted in-hospital mortality of all cases in our registry ranged from 0.3% in patients with isolated interventions and 2.0% in patients with surgical procedures up to 9.1% in patients undergoing multiple procedures. CONCLUSION: This annually updated registry of both scientific societies represents voluntary public reporting by accumulating actual information for surgical and interventional procedures in patients with congenital heart disease (CHD) in Germany. It describes advancements in cardiac medicine and is a basis for internal and external quality assurance for all participating institutions. In addition, the registry demonstrates that in Germany, both interventional and surgical procedures for treatment of CHD are offered with high medical quality.


Assuntos
Cateterismo Cardíaco , Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas/cirurgia , Adolescente , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/mortalidade , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/mortalidade , Criança , Pré-Escolar , Bases de Dados Factuais , Feminino , Alemanha , Cardiopatias Congênitas/mortalidade , Mortalidade Hospitalar , Humanos , Lactente , Masculino , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/terapia , Indicadores de Qualidade em Assistência à Saúde , Sistema de Registros , Fatores de Tempo , Resultado do Tratamento
9.
J Hum Nutr Diet ; 34(1): 13-23, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32820586

RESUMO

BACKGROUND: Extensively hydrolysed formulas (EHFs) and amino acid formulas (AAFs) with proven hypoallergenicity are used for children suffering from cow's milk allergy, when breast milk is not available. However, these feeds are often used in other medical conditions where tolerance and absorption of whole protein is affected, frequently without assessment of efficacy. This practice survey assessed the use of these feeds in paediatric conditions other than cow's milk allergy; aiming to describe the population, growth parameters and micronutrient status. METHODS: Four National Health Service tertiary paediatric centres participated in this practice survey. Inclusion: children between 0 and 18 years, consuming >25% of their estimated energy requirements of an EHF/AAF for any condition other than allergic disease. Anonymised data were collected: (i) descriptive information; (ii) indications; (iii) type and route of feeding; (iv) growth status and nutritional deficiencies; and (v) medication and vitamin and mineral supplementation. RESULTS: One hundred-and-ninety-one children were included with a median age of 19 months (interquartile range 4-63]. Seventeen percent (33/191) were on AAFs and 83% (158/191) were on EHFs. The feeds were commonly used in cancer for 26% and in critical illness for 31%. The majority (73%) of children had enteral feeds via a nasogastric tube. Nutritional biomarkers were performed in 29% of children and 83% were on a vitamin or mineral supplement. CONCLUSIONS: This practice survey found that EHFs and AAFs were used in a variety of medical conditions. Indications for feed choice varied, and evidence-based research supporting the use was scarce. Awaiting further research, children on these types of feeds should have regular nutritional monitoring.


Assuntos
Aminoácidos/administração & dosagem , Alimentos Formulados , Apoio Nutricional/métodos , Pediatria , Hidrolisados de Proteína/administração & dosagem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Padrões de Prática Médica , Medicina Estatal , Inquéritos e Questionários , Centros de Atenção Terciária , Reino Unido
10.
BJOG ; 127(12): 1568-1574, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32406174

RESUMO

OBJECTIVE: Our primary objective was to compare maternal and neonatal outcomes based on the attempted mode of extraction. Our secondary objective was to compare the outcomes based on the actual mode of extraction. DESIGN: A retrospective cohort study at a single tertiary centre between the years 2011 and 2019. SETTING: The study included 1028 cases of term pregnancies in vertex presentation that were delivered by caesarean section at the second stage of delivery. POPULATION: Patients were grouped according to the attempted mode of extraction: attempted cephalic extraction (674) and breech extraction (354). A subgroup analysis was conducted, comparing successful cephalic extraction (615), failed cephalic extraction (59) and breech extraction (354). METHODS: Both maternal and neonatal complication rates were compared between the groups. RESULTS: There were significantly more uterine incision extensions (27.4 versus 11.9%, P < 0.001) and increased need for blood transfusion (10.7 versus 6.2%, P = 0.018) in the cephalic extraction compared with the breech extraction group. The highest rate of uterine incision extensions (45.8%) and need for blood transfusion (22%) was in the subgroup of failed cephalic extraction. The rate of adverse neonatal outcomes was comparable between the two groups. However, in the subgroup of failed cephalic extraction, there were higher rates of low 1-minute Apgar scores, NICU hospitalisation and limb fractures compared with successful cephalic extractions and breech extractions (P = 0.016, 0.01, <0.001, respectively). CONCLUSIONS: Breech extraction in second-stage caesarean section is associated with fewer maternal complications compared wiith attempted cephalic extraction without increasing neonatal complication rates. TWEETABLE ABSTRACT: In breech versus cephalic extraction, breech extraction was found to have better outcomes in second-stage caesarean section.


Assuntos
Apresentação Pélvica , Cesárea , Adulto , Estudos de Coortes , Feminino , Humanos , Segunda Fase do Trabalho de Parto , Gravidez , Estudos Retrospectivos
11.
J Chem Phys ; 152(7): 074712, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32087661

RESUMO

We investigated adsorption of N2 on stoichiometric and O-rich IrO2(110) surfaces using temperature programmed desorption (TPD) experiments and density functional theory (DFT) calculations. TPD shows that N2 desorbs predominantly from the stoichiometric-IrO2(110) surface in a well-defined peak at 270 K for N2 coverages below about 0.5 ML and that a shoulder centered near 235 K develops in the N2 TPD traces as the coverage approaches saturation, indicating that adsorbed N2 molecules destabilize at high N2 coverages. Experiments of N2 adsorption onto O-rich IrO2(110) surfaces provide evidence that N2 adsorbs exclusively on the coordinatively unsaturated Ir atoms (Ircus) of the surface and that pre-adsorbed O-atoms ("on-top" oxygen) stabilize adsorbed N2 molecules, causing the main N2 TPD peak to shift toward higher temperature with increasing oxygen coverages. Consistent with prior results, our DFT calculations predict that an N2 molecule preferentially adsorbs into an upright configuration on an Ircus atom of the IrO2(110) surface and achieves a binding energy of about 100 kJ/mol. The computed binding energy agrees well with our experimental estimate of ∼90 kJ/mol for low N2 coverages on stoichiometric IrO2(110). The DFT calculations also quantitatively reproduce the observed stabilization of N2 by co-adsorption on-top O-atoms and predict the destabilization of N2 on IrO2(110) as the N2 adlayer becomes crowded at high coverages.

12.
J Hum Nutr Diet ; 33(2): 232-240, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31603281

RESUMO

BACKGROUND: Soya lecithin is present in a wide variety of foods regularly consumed by children, in the form of an emulsifier or stabiliser. Children with non-immunoglobulin (Ig)E-mediated allergies who commonly have to avoid milk and soya will have a significantly restrictive diet with reduced alternative foods if soya lecithin also has to be eliminated. The present study aimed to establish whether children with non-IgE-mediated gastrointestinal soya allergy react to soya lecithin in food products. METHODS: A double-blind, cross-over study was performed in soya-allergic children aged between 8 months and 5 years. Eligible children had their soya allergy status confirmed with a home challenge. Children were randomly assigned to either placebo or challenge dose of soya lecithin (1.5 g per day) in a custom-made biscuit. This was followed by a 1-week washout period and cross-over to another 1 week of challenge or placebo dose. Symptoms were recorded prior to commencing the study and at the end of each week's challenge. RESULTS: Twenty-two children, 16 boys, with a median age of 44 months (range 21-58 months) were recruited, although only 20 completed the full study. The median number of foods avoided in addition to soya was 3. Over the challenge period, the parents reported reactions in six cases: five cases (23%) to the placebo and one case (5%) to the challenge dose. There was no statistical difference (P = 0.025) between the groups. CONCLUSIONS: One child with a non-IgE-mediated gastrointestinal allergy had a slight reaction to soya lecithin. Although single cases may react to soya lecithin, we suggest that soya lecithin should be included in children with this delayed allergy, unless they have a confirmed reaction to traces of soya within this emulsifier.


Assuntos
Alérgenos/análise , Hipersensibilidade Alimentar/imunologia , Lecitinas/efeitos adversos , Alimentos de Soja/efeitos adversos , Proteínas de Soja/efeitos adversos , Alérgenos/efeitos adversos , Pré-Escolar , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Lactente , Lecitinas/imunologia , Masculino , Testes Cutâneos , Proteínas de Soja/imunologia
13.
Tech Coloproctol ; 24(8): 803-815, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32350733

RESUMO

BACKGROUND: Sacral neuromodulation (SNM) has become one of the main treatment options in patients with fecal incontinence. The aim of this study was to determine the efficacy of sacral neuromodulation in the treatment of low anterior resection syndrome (LARS). METHODS: A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The search was conducted using the Pubmed, Embase, Ovid, and Cochrane databases, restricted to the English language and to articles published from 2000 to November 2018. RESULTS: A total of 434 articles on the efficacy of SNM in the treatment of LARS were retrieved, and 13 studies were included in the final analysis, with a total of 114 patients treated with SNM for LARS The overall success rate excluding study heterogeneity was 83.30% [95% CI (71.33-95.25%)]. Improvement in anal continence was seen in several clinical and functional parameters, including the Wexner Score [10.78 points, 95% CI (8.55-13.02), p < 0.0001], manometric maximum resting pressure [mean improvement of 6.37 mm/Hg, 95% CI (2.67-10.07), p = 0.0007], maximum squeeze pressure [mean improvement of 17.99 mm/Hg, 95% CI (17.42-18.56), p < 0.0001] and maximum tolerated volume [mean improvement of 22.74 ml, 95% CI (10.65-34.83), p = 0.0002]. Quality of life questionnaires also demonstrated significant improvement in patients' quality of life, but were reported only in a small group of included patients. CONCLUSIONS: SNM significantly improves symptoms and quality of life in patients suffering from fecal incontinence following low anterior resection.


Assuntos
Terapia por Estimulação Elétrica , Incontinência Fecal , Neoplasias Retais , Incontinência Fecal/etiologia , Incontinência Fecal/terapia , Humanos , Complicações Pós-Operatórias/terapia , Qualidade de Vida , Síndrome , Resultado do Tratamento
14.
Opt Lett ; 44(21): 5222-5225, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674973

RESUMO

We present a power-scalable laser source with 30 fs pulse duration, 530 W average power at 500 kHz repetition rate, and beam quality M2<1.2. The compact and efficient setup consists of ytterbium-based Innoslab amplifiers and subsequent nonlinear pulse compression with an argon-filled Herriott cell.

15.
J Hum Nutr Diet ; 32(2): 175-184, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30412327

RESUMO

BACKGROUND: Elimination diets required for the management of food allergies increase the risk for poor growth in children. Currently, no worldwide data exist on this topic and limited published data exist on the impact of atopic comorbidity, type of allergy and foods eliminated on growth. We therefore set out to perform a worldwide survey on growth and impacting factors in food allergic children. METHODS: A prospective growth survey was performed of children (aged 0-16 years) on an elimination diet with confirmed immunoglobulin (Ig)E and non-IgE mediated food allergies. Data collected included: weight-for-age, weight-for-height, height-for-age, head circumference, body mass index, type of food allergy and eliminated foods, allergic comorbidities and replacement milk/breast milk. Multivariable regression analysis was used to establish factors that affected growth. RESULTS: Data from 430 patients from twelve allergy centres were analysed: median age at diagnosis and data collection was 8 months and 23 months, respectively. Pooled data indicated that 6% were underweight, 9% were stunted, 5% were undernourished and 8% were overweight. Cow's milk elimination lead to a lower weight-for-height Z-scores than other food eliminations and mixed IgE and non-IgE mediated allergy had lower height-for-age Z-scores than IgE mediated allergy. Children with only non-IgE mediated allergies had lower weight-for-height and body mass index. Atopic comorbidities did not impact on growth. CONCLUSIONS: Stunting is more common in children with food allergies than low weight. Children particularly at risk of poor growth are those with non-IgE and mixed IgE and non-IgE mediated allergies, as well as those with cow's milk allergy.


Assuntos
Estatura/fisiologia , Peso Corporal/fisiologia , Hipersensibilidade Alimentar/fisiopatologia , Transtornos do Crescimento/etiologia , Magreza/etiologia , Adolescente , Criança , Desenvolvimento Infantil/fisiologia , Pré-Escolar , Feminino , Hipersensibilidade Alimentar/complicações , Gráficos de Crescimento , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Análise de Regressão , Inquéritos e Questionários
16.
Neuroimage ; 174: 308-316, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29548847

RESUMO

The accumulation of ß-amyloid plaques is a hallmark of Alzheimer's disease (AD), and recently published data suggest that increased brain iron burden may reflect pathologies that synergistically contribute to the development of cognitive dysfunction. While preclinical disease stages are considered most promising for therapeutic intervention, the link between emerging AD-pathology and earliest clinical symptoms remains largely unclear. In the current study we therefore investigated local correlations between iron and ß-amyloid plaques, and their possible association with cognitive performance in healthy older adults. 116 older adults (mean age 75 ±â€¯7.4 years) received neuropsychological testing to calculate a composite cognitive score of performance in episodic memory, executive functioning, attention, language and communication. All participants were scanned on a combined PET-MRI instrument and were administered T1-sequences for anatomical mapping, quantitative susceptibility mapping (QSM) for assessing iron, and 18F-Flutemetamol-PET for estimating ß-amyloid plaque load. Biological parametric mapping (BPM) was used to generate masks indicating voxels with significant (p < 0.05) correlation between susceptibility and 18F-Flutemetamol-SUVR. We found a bilateral pattern of clusters characterized by a statistical relationship between magnetic susceptibility and 18F-Flutemetamol-SUVR, indicating local correlations between iron and ß-amyloid plaque deposition. For two bilateral clusters, located in the frontal and temporal cortex, significant relationships (p<0.05) between local ß-amyloid and the composite cognitive performance score could be observed. No relationship between whole-cortex ß-amyloid plaque load and cognitive performance was observable. Our data suggest that the local correlation of ß-amyloid plaque load and iron deposition may provide relevant information regarding cognitive performance of healthy older adults. Further studies are needed to clarify pathological correlates of the local interaction of ß-amyloid, iron and other causes of altered magnetic susceptibility.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Cognição , Ferro/metabolismo , Placa Amiloide/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Compostos de Anilina , Benzotiazóis , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons
17.
Clin Exp Allergy ; 48(2): 121-137, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29315948

RESUMO

Food allergy is becoming increasingly common in infants and young children. This article set out to explain the different factors that should be taken into account during an individualized allergy consultation: Foods to avoid and degree of avoidance, suitable alternatives, self-management skills, co- and cross-reactive allergens and novel allergens alongside the role of the industry in allergen avoidance, importance of nutritional aspects of the diet and the future directions that nutritional guidance make take. Allergy management advice should be individualized to provide a patient-specific approach. Changes in the management of food allergies have in particular occurred in nut, milk and egg allergies over the past few years. There has also been a progressive increase in our understanding of cross-reactivity between different foods and also food and aero-allergens. A patient-specific approach of allergen avoidance should consider factors relating to industry and the environment such as food and nutrition literacy, threshold levels, cross-contact/contamination and safe eating away from home. Increasing migration and travel has also led to exposure of unfamiliar foods. As understanding improves on individual allergens and threshold levels, food labels and food labelling laws are affected. Allergy specialist dietitians should also keep up to date with the latest information on nutrition, the gut microbiome and the immune system to incorporate nutrition strategies in a dietetic consultation using an evidence-based approach.


Assuntos
Alérgenos/imunologia , Hipersensibilidade Alimentar/dietoterapia , Hipersensibilidade Alimentar/imunologia , Alimentos/efeitos adversos , Fatores Etários , Animais , Criança , Pré-Escolar , Reações Cruzadas/imunologia , Dieta , Gerenciamento Clínico , Meio Ambiente , Exposição Ambiental , Métodos de Alimentação , Humanos , Lactente , Estado Nutricional , Apoio Nutricional , Fatores de Risco
18.
Ultrasound Obstet Gynecol ; 52(4): 467-472, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29607569

RESUMO

OBJECTIVE: Fetal isolated ventricular asymmetry (IVA) is a relatively common finding in pregnancy, but data regarding its effect on neurodevelopmental outcome are scarce and founded principally on ultrasound-based studies. The purpose of this study was to assess the neurodevelopmental outcome of IVA cases in a magnetic resonance imaging (MRI)-based study. METHODS: Cases referred for fetal brain MRI as part of the assessment of IVA without ventriculomegaly (lateral ventricular atrial diameter ≤ 10 mm), identified during routine ultrasound examination, were assessed for possible inclusion. Asymmetry was defined as a difference in width of ≥ 2 mm between the two lateral ventricles. Forty-three cases were included in the study group and compared with a control group of 94 normal cases without IVA. Children were assessed at ages 13-74 months using the Vineland-II Adaptive Behavior Scales (VABS-II). RESULTS: VABS-II scores were within normal range. There was no significant difference in composite VABS-II score between the study and control groups (106.5 vs 108.0; P = 0.454). VABS-II scores did not differ between the groups when matched for gender and age at VABS-II interview (109.6 in study group vs 107.8 in control group; P = 0.690). CONCLUSION: In cases of IVA without ventriculomegaly on MRI, neurodevelopmental test scores were normal and did not differ from cases without IVA. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Adaptação Psicológica/fisiologia , Ventrículos Cerebrais/anormalidades , Imageamento por Ressonância Magnética , Transtornos do Neurodesenvolvimento/diagnóstico por imagem , Adulto , Fatores Etários , Ventrículos Cerebrais/diagnóstico por imagem , Ventrículos Cerebrais/fisiopatologia , Pré-Escolar , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Masculino , Transtornos do Neurodesenvolvimento/etiologia , Transtornos do Neurodesenvolvimento/fisiopatologia , Gravidez
19.
J Appl Microbiol ; 124(2): 431-443, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29130635

RESUMO

AIMS: The aim of this study was to analyse arsenic (As) transformation and biosorption by indigenous As-resistant bacteria both in planktonic and biofilm modes of growth. METHODS AND RESULTS: As-resistant bacteria were isolated from industrial waste water and strain PT2, and identified as Exiguobacterium profundum through 16S rRNA gene sequencing was selected for further study. As transformation and biosorption by E. profundumPT2 was determined by HPLC-ICP-MS analysis. Planktonic cultures reduced 3·73 mmol l-1 As5+ into As3+ from artificial waste water effluent after 48-h incubation. In case of biosorption, planktonic cultures and biofilms exhibited 25·2 and 29·4 mg g-1 biomass biosorption, respectively. As biosorption kinetics followed Freundlich isotherm and pseudo second-order model. Biofilm formation peaked after 3 days of incubation, and in the presence of As stress, biofilm formation was significantly affected in contrast to control (P < 0·05). Homogeneous nature of mature biofilms with an increased demand of nutrients was revealed by minimum roughness and maximum surface to biovolume ratio measured through CLSM analysis. CONCLUSION: Indigenous As-resistant E. profundumPT2 was found capable of As transformation and biosorption both in the form of planktonic cultures and biofilms. SIGNIFICANCE AND IMPACT OF THE STUDY: Indigenous biofilm forming E. profundum PT2 revealing As biosorption and biotransformation potential is presented an eco-friendly and cost-effective source for As remediation that can be implemented for waste water treatment.


Assuntos
Arsênio/metabolismo , Bacillaceae/metabolismo , Biofilmes , Poluentes Químicos da Água/metabolismo , Adsorção , Bacillaceae/química , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Biomassa , Biotransformação , Resíduos Industriais/análise , Cinética , RNA Ribossômico 16S/metabolismo , Águas Residuárias/análise
20.
J Appl Microbiol ; 124(1): 179-187, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29119696

RESUMO

AIMS: Pathogenic bacteria can spread between individuals or between food items via the surfaces they share. Limiting the survival of pathogens on surfaces, therefore, presents an opportunity to limit at least one route of how pathogens spread. In this study, we propose that a simple coating with the essential oil isoeugenol can be used to circumvent the problem of bacterial transfer via surfaces. METHODS AND RESULTS: Two commonly used materials, stainless steel and polyethylene, were coated by physical adsorption, and the coatings were characterized by Raman spectroscopy, atomic force microscopy and water contact angle measurements. We quantified and visualized the colonization of coated and uncoated surfaces by three bacteria: Staphylococcus aureus, Listeria monocytogenes and Pseudomonas fluorescens. No viable cells were detected on surfaces coated with isoeugenol. CONCLUSIONS: The isoeugenol coating prepared with simple adsorption proved effective in preventing biofilm formation on stainless steel and polyethylene surfaces. The result was caused by the antibacterial effect of isoeugenol, as the coating did not diminish the adhesive properties of the surface. SIGNIFICANCE AND IMPACT OF THE STUDY: Our study demonstrates that a simple isoeugenol coating can prevent biofilm formation of S. aureus, L. monocytogenes and P. fluorescens on two commonly used surfaces.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Eugenol/análogos & derivados , Listeria monocytogenes/fisiologia , Polietileno/química , Pseudomonas fluorescens/fisiologia , Staphylococcus aureus/fisiologia , Adsorção , Antibacterianos/química , Aderência Bacteriana/efeitos dos fármacos , Eugenol/química , Eugenol/farmacologia , Humanos , Listeria monocytogenes/efeitos dos fármacos , Pseudomonas fluorescens/efeitos dos fármacos , Aço Inoxidável/química , Staphylococcus aureus/efeitos dos fármacos
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