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1.
Sci Total Environ ; 918: 170589, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38309350

RESUMO

A modelling framework was developed to facilitate a probabilistic assessment of health risks posed by pesticide exposure via drinking water due to runoff, with the inclusion of influential site conditions and in-stream processes. A Monte-Carlo based approach was utilised to account for the inherent variability in pesticide and population properties, as well as site and climatic conditions. The framework presented in this study was developed with an ability to integrate different data sources and adapt the model for various scenarios and locations to meet the users' needs. The results from this model can be used by farm advisors and catchment managers to identify lower risk pesticides for use for given soil and site conditions and implement risk mitigation measures to protect water resources. Pesticide concentrations in surface water, and their risk of regulatory threshold exceedances, were simulated for fifteen pesticides in an Irish case study. The predicted concentrations in surface water were then used to quantify the level of health risk posed to Irish adults and children. The analysis indicated that herbicides triclopyr and MCPA occur in the greatest concentrations in surface water, while mecoprop was associated with the highest potential for health risks. The study found that the modelled pesticides posed little risk to human health under current application patterns and climatic conditions in Ireland using international acceptable intake values. A sensitivity study conducted examined the impact seasonal conditions, timing of application, and instream processes, have on the transport of pesticides to drinking water.


Assuntos
Água Potável , Herbicidas , Praguicidas , Poluentes Químicos da Água , Criança , Humanos , Praguicidas/análise , Água Potável/análise , Poluentes Químicos da Água/análise , Herbicidas/análise , Medição de Risco
2.
Ultrasound Obstet Gynecol ; 63(2): 206-213, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37675647

RESUMO

OBJECTIVE: The maternal cardiovascular system of women with hypertensive disorders of pregnancy (HDP) can be impaired, with higher rates of left ventricular (LV) remodeling and diastolic dysfunction compared to those with normotensive pregnancy. The primary objective of this prospective study was to correlate cardiac indices obtained by transthoracic echocardiography (TTE) and circulating angiogenic markers, such as soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF). METHODS: In this study, 95 women with a pregnancy complicated by HDP and a group of 25 with an uncomplicated pregnancy at term underwent TTE and blood tests to measure sFlt-1 and PlGF during the peripartum period (before delivery or within a week of giving birth). Spearman's rank correlation was used to derive correlation coefficients between biomarkers and cardiac indices in the HDP and control populations. RESULTS: The HDP group included 61 (64.2%) pre-eclamptic patients and, among them, 42 (68.9%) delivered before 37 weeks' gestation. Twelve women with HDP (12.6%) underwent blood sampling and TTE after delivery, and, as they showed significantly lower levels of angiogenic markers, they were excluded from the analysis. There was a correlation between sFlt-1 and LV mass index (LVMI) (r = 0.246; P = 0.026) and early diastolic mitral inflow velocity (E) and early diastolic mitral annular velocity (e') ratio (r = 0.272; P = 0.014) in the HDP group (n = 83), while in the controls, sFlt-1 showed a correlation with relative wall thickness (r = 0.409; P = 0.043), lateral e' (r = -0.562; P = 0.004) and E/e' ratio (r = 0.417; P = 0.042). PlGF correlated with LVMI (r = -0.238; P = 0.031) in HDP patients and with lateral e' (r = 0.466; P = 0.022) in controls. sFlt-1/PlGF ratio correlated with lateral e' (r = -0.568; P = 0.004) and E/e' ratio (r = 0.428; P = 0.037) in controls and with LVMI (r = 0.252; P = 0.022) and E/e' ratio (r = 0.269; P = 0.014) in HDP. CONCLUSIONS: Although the current data are not able to infer causality, they confirm the intimate relationship between the maternal cardiovascular system and angiogenic markers that are used both to diagnose and indicate the severity of HDP. © 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
Hipertensão Induzida pela Gravidez , Pré-Eclâmpsia , Gravidez , Feminino , Humanos , Estudos Prospectivos , Fator de Crescimento Placentário , Pré-Eclâmpsia/diagnóstico , Biomarcadores , Ecocardiografia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fator A de Crescimento do Endotélio Vascular
3.
Ultrasound Obstet Gynecol ; 63(1): 75-80, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37448160

RESUMO

OBJECTIVE: Pre-eclampsia (PE) is a pregnancy complication associated with premature cardiovascular disease morbidity and mortality (i.e. before 60 years of age or in the first year postpartum). PE is associated with adverse left ventricular (LV) remodeling in the peri- and postpartum periods, an independent risk factor for cardiovascular disease. This study aimed to compare LV geometry by LV mass (LVM) and LVM index (LVMI) between participants with a high vs low screening risk for preterm PE in the first trimester. METHODS: This was a prospective cohort study of singleton pregnancies between 11 + 0 and 13 + 6 weeks' gestation that underwent screening for preterm PE as part of their routine first-trimester ultrasound assessment at a tertiary center in London, UK, from February 2019 until March 2020. Screening for preterm PE was performed using the Fetal Medicine Foundation algorithm. Participants with a screening risk of ≥ 1 in 50 for preterm PE were classified as high risk and those with a screening risk of ≤ 1 in 500 were classified as low risk. All participants underwent two-dimensional and M-mode transthoracic echocardiography. RESULTS: A total of 128 participants in the first trimester of pregnancy were included in the analysis, with 57 (44.5%) participants screened as low risk and 71 (55.5%) participants as high risk for PE. The risk groups did not vary in maternal age and gestational age at assessment. Maternal body surface area and body mass index were significantly higher in the high-risk group (all P < 0.05). The high-risk participants were significantly more likely to be Afro-Caribbean, nulliparous and have a family history of hypertensive disease in pregnancy as well as other cardiovascular disease (all P < 0.05). In addition, mean arterial blood pressure (P < 0.001), mean heart rate (P < 0.001), median LVM (130.06 (interquartile range, 113.62-150.50) g vs 97.44 (81.68-114.16) g; P < 0.001) and mean LVMI (72.87 ± 12.2 g/m2 vs 57.54 ± 12.72 g/m2 ; P < 0.001) were significantly higher in the high-risk group. Consequently, those in the high-risk group were more likely to have abnormal LV geometry (37.1% vs 7.0%; P < 0.001). CONCLUSIONS: Early echocardiographic assessment in participants at high risk of preterm PE may unmask clinically healthy individuals who are at increased risk for future cardiovascular disease. Adverse cardiac remodeling in the first trimester of pregnancy may be an indicator of decreased cardiovascular reserve and subsequent dysfunctional cardiovascular adaptation in pregnancy. © 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
Hipertrofia Ventricular Esquerda , Pré-Eclâmpsia , Feminino , Humanos , Recém-Nascido , Gravidez , Biomarcadores , Idade Gestacional , Fator de Crescimento Placentário , Pré-Eclâmpsia/diagnóstico por imagem , Primeiro Trimestre da Gravidez , Estudos Prospectivos , Fatores de Risco , Artéria Uterina , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/etiologia , Complicações Cardiovasculares na Gravidez , Remodelação Ventricular , Ecocardiografia
4.
Eur J Sport Sci ; 23(8): 1800-1809, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36815759

RESUMO

We aimed to assess the prognostic utility of different parameters routinely assessed from cardiopulmonary exercise testing (CPET) and exercise echocardiography in adults with end-stage renal disease (ESRD). Forty-two ESRD (37 male) individuals (age: 58 ± 13 years, height: 169.30 ± 8.30 cm, weight: 81 ± 15 kg, body surface area: 1.92 ± 0.20 m2) underwent a maximal/symptom limited CPET, with a full cross-sectional echocardiogram performed at baseline and peak exercise. All participants were prospectively followed over a 10-year period, with all-cause mortality as the primary endpoint. After the follow-up period, a total of 19 participants (45%) died. Left atrial size (4.70 ± 0.70 vs. 3.65 ± 0.50 cm, P < 0.001) and anteroseptal wall thickness (1.28 ± 0.40 vs. 1.06 ± 0.02 cm, P = 0.002) were significantly greater in those that died, while peak heart rate was significantly lower (108 ± 12 vs. 128 ± 14 bpm, P < 0.001). The prevalence of myocardial ischaemia (13 vs. 8 participants, P = 0.03) was significantly greater, while peak VO2 (9.80 ± 2.10 vs. 15.90 ± 4.30 ml·kg-1·min-1, P < 0.001) was significantly lower in those that died. Following multivariate cox regression, myocardial ischaemia (Hazard Ratio 3.08; 95% Confidence Interval 1.09-8.70; P = 0.03) and peak VO2 (HR 0.73; 95% CI 0.64-0.84; P < 0.001) were significant independent predictors of 10-year all-cause mortality. This is the first study to establish peak VO2 as powerful marker of all-cause mortality when assessed with clinical, resting and stress echocardiography parameters in people with ESRD over a 10-year follow up period. This observation indicates that, in clinical practice, CPET and exercise echocardiography may serve as valuable tools for the risk stratification of individuals with ESRD.HighlightsWe aimed to assess the prognostic utility of cardiopulmonary exercise testing (CPET) and exercise echocardiography in end-stage renal disease (ESRD) with 10-year mortality.Peak aerobic capacity and the presence of ischaemic heart disease were independently associated with all-cause mortality.This observation indicates that, in clinical practice, CPET and exercise echocardiography may serve as valuable tools for the risk stratification of individuals with end-stage renal disease.


Assuntos
Falência Renal Crônica , Isquemia Miocárdica , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Ecocardiografia sob Estresse , Teste de Esforço , Estudos Transversais , Consumo de Oxigênio
5.
J Environ Manage ; 323: 116102, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36103789

RESUMO

This study reports the kinetics and isotherms of the adsorption of five herbicides, MCPA, mecoprop-P, 2,4-D, fluroxypyr and triclopyr, from aqueous solutions onto a range of raw and pyrolysed waste materials originating from an industrial setting. The raw waste materials investigated demonstrated little capability for any herbicide adsorption. Granulated activated carbon (GAC) was capable of the best removal of the herbicides, with >95% removal observed. A first order kinetic model fitted the data best for GAC adsorption of 2,4-D, while a pseudo-first order model fitted the data best for GAC adsorption of fluroxypyr and triclopyr, indicating that adsorption was via physisorption. A pseudo-second order kinetic model fitted the GAC adsorption of MCPA and mecoprop-P, which is indicative of chemisorption. The adsorption of the herbicides in all cases was best described by the Freundlich model, indicating that adsorption occurred onto heterogeneous surfaces.


Assuntos
Ácido 2-Metil-4-clorofenoxiacético , Herbicidas , Poluentes Químicos da Água , Ácido 2,4-Diclorofenoxiacético , Ácido 2-Metil-4-clorofenoxiacético/análogos & derivados , Acetatos , Adsorção , Carvão Vegetal , Glicolatos , Concentração de Íons de Hidrogênio , Cinética , Piridinas , Termodinâmica , Resíduos , Água
6.
Sci Total Environ ; 829: 154532, 2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35302029

RESUMO

This paper presents a novel scoring system which facilitates a relative ranking of pesticide risk to human health arising from contaminated drinking water. This method was developed to identify risky pesticides to better inform monitoring programmes and risk assessments. Potential risk was assessed considering pesticide use, chronic human health effects and environmental fate. Site-specific soil conditions, such as soil erodibility, hydrologic group, soil depth, clay, sand, silt, and organic carbon content of soil, were incorporated to demonstrate how pesticide fate can be influenced by the areas in which they are used. The indices of quantity of use, consequence and likelihood of exposure, hazard score and quantity-weighted hazard score were used to describe the level of concern that should be attributed to a pesticide. Metabolite toxicity and persistence were also considered in a separate scoring to highlight the contribution metabolites make to overall pesticide risk. This study presents two sets of results for 63 pesticides in an Irish case study, (1) risk scores calculated for the parent compounds only and (2) a combined pesticide-metabolite risk score. In both cases the results are assessed for two locations with differing soil and hydrological properties. The method developed in this paper can be adapted by pesticide users to assess and compare pesticide risk at site level using pesticide hazard scores. Farm advisors, water quality monitors, and catchment managers can apply this method to screen pesticides for human health risk at a regional or national level.


Assuntos
Água Potável , Praguicidas , Poluentes Químicos da Água , Monitoramento Ambiental , Humanos , Praguicidas/análise , Praguicidas/toxicidade , Solo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Poluição da Água , Qualidade da Água
7.
Ultrasound Obstet Gynecol ; 59(5): 619-626, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35000243

RESUMO

OBJECTIVE: Twin pregnancies are at increased risk of developing hypertensive disorders of pregnancy (HDP) compared with singleton pregnancies, resulting in a substantially higher rate of maternal and perinatal complications. The strain caused by twin pregnancy on the maternal cardiovascular system has not been studied extensively. The objective of this study was to evaluate the changes in maternal cardiac morphology and diastolic function in a cohort of women with normotensive and those with hypertensive twin pregnancies. METHODS: This was a cross-sectional study conducted at a tertiary referral university center. Women with singleton or twin pregnancy were enrolled prospectively to undergo maternal transthoracic echocardiography throughout pregnancy. Multiples of the median (MoM) were calculated for each index using a reference group of uncomplicated singleton pregnancies (n = 411) in order to adjust for changes associated with gestational age. Cardiac findings were indexed for body surface area and compared among normotensive twin pregnancies, singleton pregnancies complicated by HDP and twin pregnancies complicated by HDP. RESULTS: The total cohort included 119 HDP singleton pregnancies, 52 normotensive twin pregnancies and 24 HDP twin pregnancies. Left ventricular mass index (LVMi) MoM (median (interquartile range)) did not differ between singleton pregnancies complicated by HDP and normotensive twin pregnancies, but was significantly higher in HDP twin compared with HDP singleton pregnancies (1.31 (1.08-1.53) vs 1.17 (0.98-1.35), P = 0.032). Two diastolic indices, left atrial volume index MoM (1.12 (0.66-1.38) vs 0.65 (0.55-0.84), P = 0.003) and E/e' MoM (1.29 (1.09-1.54) vs 0.99 (0.99-1.02), P = 0.036), were significantly higher in HDP twin compared with normotensive twin pregnancies. In normotensive twin compared with HDP singleton pregnancies, stroke volume index (SVi) MoM was higher (1.20 (1.03-1.36) vs 1.00 (0.81-1.15), P = 0.004) and total vascular resistance index (TVRi) was lower (0.73 (0.70-0.86) vs 1.29 (1.04-1.56), P < 0.0001). In contrast, SVi MoM was lower (1.10 (1.02-1.35) vs 1.20 (1.03-1.36), P = 0.018) and TVRi was higher (1.00 (0.88-1.31) vs 0.73 (0.70-0.86), P = 0.029) in HDP twin compared with normotensive twin pregnancies. CONCLUSION: The maternal cardiovascular system is altered severely in twin pregnancy with or without HDP. Despite the low total vascular resistance, cardiac changes in normotensive twin pregnancies are comparable to those seen in singleton pregnancies complicated by HDP, reflecting the high cardiovascular demand imposed by twin pregnancy. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Pré-Eclâmpsia , Gravidez de Gêmeos , Estudos Transversais , Ecocardiografia , Feminino , Idade Gestacional , Humanos , Pré-Eclâmpsia/diagnóstico por imagem , Gravidez
8.
Ultrasound Obstet Gynecol ; 59(3): 365-370, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34309939

RESUMO

OBJECTIVE: Hypertensive disorders of pregnancy (HDP) are associated with significant myocardial dysfunction on echocardiography. The impact of hemodynamic changes related to volume redistribution following delivery on myocardial function in women with HDP has not been evaluated systematically. The aim of this study was to compare echocardiographic findings immediately before and after delivery in women with HDP. METHODS: This was a prospective longitudinal study including 30 women with a diagnosis of HDP who underwent two consecutive transthoracic echocardiographic (TTE) examinations, before delivery and in the early postpartum period. Paired comparisons of the findings from the two assessments were performed. RESULTS: Left-ventricular (LV) concentric remodeling or hypertrophy was detected in 21 (70%) patients. There was no significant difference in cardiac morphology indices such as LV mass index (78.9 ± 16.3 g/m2 vs 77.9 ± 15.4 g/m2 ; P = 0.611) or relative wall thickness (0.45 ± 0.1 vs 0.44 ± 0.1; P = 0.453) before vs after delivery. LV diastolic function did not demonstrate any peripartum variation, with similar left-atrial volume (52.4 ± 15.3 mL vs 51.0 ± 15.6 mL; P = 0.433), lateral E' (0.12 ± 0.03 m/s vs 0.12 ± 0.03 m/s; P = 0.307) and E/E' ratio (7.9 ± 2.2 vs 7.9 ± 1.7; P = 0.934) before vs after delivery. Systolic function indices, such as LV ejection fraction (57.5 ± 3.4% vs 56.4 ± 2.1%; P = 0.295) and global longitudinal strain (-15.3 ± 2.6% vs -15.1 ± 3.1%; P = 0.582), also remained unchanged between before vs after delivery. CONCLUSIONS: Maternal hemodynamic changes associated with delivery did not influence significantly peripartum TTE indices in women with HDP. Suboptimal maternal echocardiographic findings in HDP are likely to be the consequence of chronic pregnancy cardiovascular load changes or pre-existing maternal cardiovascular impairment. Severity and persistence of myocardial dysfunction in the postpartum period may be related to the long-term maternal cardiovascular disease legacy of HDP. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Hipertensão Induzida pela Gravidez , Pré-Eclâmpsia , Ecocardiografia , Feminino , Humanos , Hipertensão Induzida pela Gravidez/diagnóstico por imagem , Estudos Longitudinais , Período Periparto , Gravidez , Estudos Prospectivos , Função Ventricular Esquerda , Remodelação Ventricular
9.
Nat Commun ; 12(1): 2660, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976209

RESUMO

The implementation of nano-engineered composite oxides opens up the way towards the development of a novel class of functional materials with enhanced electrochemical properties. Here we report on the realization of vertically aligned nanocomposites of lanthanum strontium manganite and doped ceria with straight applicability as functional layers in high-temperature energy conversion devices. By a detailed analysis using complementary state-of-the-art techniques, which include atom-probe tomography combined with oxygen isotopic exchange, we assess the local structural and electrochemical functionalities and we allow direct observation of local fast oxygen diffusion pathways. The resulting ordered mesostructure, which is characterized by a coherent, dense array of vertical interfaces, shows high electrochemically activity and suppressed dopant segregation. The latter is ascribed to spontaneous cationic intermixing enabling lattice stabilization, according to density functional theory calculations. This work highlights the relevance of local disorder and long-range arrangements for functional oxides nano-engineering and introduces an advanced method for the local analysis of mass transport phenomena.

10.
Tissue Eng Part A ; 27(1-2): 26-36, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32098585

RESUMO

We previously developed a recombinant growth factor-free, three-dimensional (3D)-printed material comprising hydroxyapatite (HA) and demineralized bone matrix (DBM) for bone regeneration. This material has demonstrated the capacity to promote re-mineralization of the DBM particles within the scaffold struts and shows potential to promote successful spine fusion. Here, we investigate the role of geometry and architecture in osteointegration, vascularization, and facilitation of spine fusion in a preclinical model. Inks containing HA and DBM particles in a poly(lactide-co-glycolide) elastomer were 3D-printed into scaffolds with varying relative strut angles (90° vs. 45° advancing angle), macropore size (0 µm vs. 500 µm vs. 1000 µm), and strut alignment (aligned vs. offset). The following configurations were compared with scaffolds containing no macropores: 90°/500 µm/aligned, 45°/500 µm/aligned, 90°/1000 µm/aligned, 45°/1000 µm/aligned, 90°/1000 µm/offset, and 45°/1000 µm/offset. Eighty-four female Sprague-Dawley rats underwent spine fusion with bilateral placement of the various scaffold configurations (n = 12/configuration). Osteointegration and vascularization were assessed by using microComputed Tomography and histology, and spine fusion was assessed via blinded manual palpation. The 45°/1000 µm scaffolds with aligned struts achieved the highest average fusion score (1.61/2) as well as the highest osteointegration score. Both the 45°/1000 µm/aligned and 90°/1000 µm/aligned scaffolds elicited fusion rates of 100%, which was significantly greater than the 45°/500 µm/aligned iteration (p < 0.05). All porous scaffolds were fully vascularized, with blood vessels present in every macropore. Vessels were also observed extending from the native transverse process bone, through the protrusions of new bone, and into the macropores of the scaffolds. When viewed independently, scaffolds printed with relative strut angles of 45° and 90° each allowed for osteointegration sufficient to stabilize the spine at L4-L5. Within those parameters, a pore size of 500 µm or greater was generally sufficient to achieve unilateral fusion. However, our results suggest that scaffolds printed with the larger pore size and with aligned struts at an advancing angle of 45° may represent the optimal configuration to maximize osteointegration and fusion capacity. Overall, this work suggests that the HA/DBM composite scaffolds provide a conducive environment for bone regeneration as well as vascular infiltration. This technology, therefore, represents a novel, growth-factor-free biomaterial with significant potential as a bone graft substitute for use in spinal surgery. Impact statement We previously developed a recombinant growth factor-free, three-dimensional (3D)-printed composite material comprising hydroxyapatite and demineralized bone matrix for bone regeneration. Here, we identify a range of 3D geometric and architectural parameters that support the preclinical success of the scaffold, including efficient vascularization, osteointegration, and, ultimately, spinal fusion. Our results suggest that this material holds great promise as a clinically translatable biomaterial for use as a bone graft substitute in orthopedic procedures requiring bone regeneration.


Assuntos
Fusão Vertebral , Animais , Feminino , Impressão Tridimensional , Ratos , Ratos Sprague-Dawley , Alicerces Teciduais , Microtomografia por Raio-X
11.
Radiography (Lond) ; 27(1): 67-74, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32693990

RESUMO

INTRODUCTION: This study investigates instances of elevated radiation dose on a radiation tracking system to determine their aetiologies. It aimed to investigate the impact of radiographer feedback on these alerts. METHODS: Over two six-month periods 11,298 CT examinations were assessed using DoseWatch. Red alerts (dose length products twice the median) were identified and two independent reviewers established whether alerts were true (unjustifiable) or false (justifiable). During the second time period radiographers used a feedback tool to state the cause of the alert. A Chi-Square test was used to assess whether red alert incidence decreased following the implementation of radiographer feedback. RESULTS: There were 206 and 357 alerts during the first and second time periods, respectively. These occurred commonly with CT pulmonary angiography, brain, and body examinations. Procedural documentation errors and patient size accounted for 57% and 43% of false alerts, respectively. Radiographer feedback was provided for 17% of studies; this was not associated with a significant change in the number of alerts, but the number of true alerts declined (from 7 to 3) (χ2 = 4.14; p = 0.04). CONCLUSION: Procedural documentation errors as well as patient-related factors are associated with false alerts in DoseWatch. Implementation of a radiographer feedback tool reduced true alerts. IMPLICATIONS FOR PRACTICE: The implementation of a radiographer feedback tool reduced the rate of true dose alerts. Low uptake with dose alert systems is an issue; the workflow needs to be considered to address this.


Assuntos
Sistemas de Registro de Ordens Médicas , Documentação , Retroalimentação , Humanos , Doses de Radiação , Tomografia Computadorizada por Raios X
12.
Ultrasound Obstet Gynecol ; 56(2): 240-246, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31785176

RESUMO

OBJECTIVE: To determine whether maternal cardiac adaptation at term differs between women with, and those without, gestational diabetes mellitus (GDM). METHODS: This was a prospective case-control study of pregnant women at term with or without GDM. For both cases and controls, only women without any comorbidity or form of pre-existing diabetes who had a singleton pregnancy without complication (such as pre-eclampsia or fetal growth restriction) were included. All women underwent conventional and speckle-tracking echocardiography to assess both the left- and right-heart geometry and function. RESULTS: A total of 40 women with GDM and 40 healthy controls were enrolled. Women with GDM, compared with controls, had a significantly higher heart rate (83 ± 10 vs 75 ± 9 beats per min; P < 0.001), left ventricular (LV) relative wall thickness (0.43 ± 0.07 vs 0.37 ± 0.08; P < 0.001), LV early diastolic transmitral valve velocity (E) (0.80 ± 0.15 vs 0.73 ± 0.12 m/s; P = 0.026) and LV late diastolic transmitral valve velocity (A) (0.65 ± 0.13 vs 0.57 ± 0.11 m/s; P = 0.006). In women with GDM compared with controls, speckle-tracking analysis revealed a significant reduction in LV global longitudinal strain (GLS) (-16.29 ± 2.26 vs -17.61 ± 1.89; P = 0.012), LV endocardial GLS (-18.50 ± 2.59 vs -19.84 ± 2.35; P = 0.031) and LV epicardial GLS (-14.40 ± 2.01 vs -15.73 ± 1.66; P = 0.005). Right ventricular (RV) analysis revealed a reduced pulmonary acceleration time (58 ± 10 vs 66 ± 11 ms; P = 0.001) and RV E/A ratio (1.13 ± 0.18 vs 1.29 ± 0.35; P = 0.017), as well as a higher RV myocardial systolic annular velocity (0.16 ± 0.04 vs 0.14 ± 0.02; P = 0.023) and peak late diastolic transtricuspid valve velocity (0.46 ± 0.1 m/s vs 0.39 ± 0.08 m/s; P = 0.001), in women with GDM compared to controls. CONCLUSIONS: Our findings show that even a short period of exposure to hyperglycemia, as occcurs in women with GDM, is associated with significant maternal functional cardiac impairment at term. Given these findings, further study of postnatal maternal cardiovascular recovery after GDM pregnancy is warranted. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Adaptação Fisiológica , Diabetes Gestacional/fisiopatologia , Ventrículos do Coração/fisiopatologia , Complicações Cardiovasculares na Gravidez/etiologia , Disfunção Ventricular/etiologia , Adulto , Estudos de Casos e Controles , Diabetes Gestacional/diagnóstico por imagem , Ecocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Gravidez , Estudos Prospectivos , Nascimento a Termo/fisiologia , Ultrassonografia Pré-Natal
13.
Tissue Eng Part A ; 26(3-4): 157-166, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31469055

RESUMO

Although numerous spinal biologics are commercially available, a cost-effective and safe bone graft substitute material for spine fusion has yet to be proven. In this study, "3D-Paints" containing varying volumetric ratios of hydroxyapatite (HA) and human demineralized bone matrix (DBM) in a poly(lactide-co-glycolide) elastomer were three-dimensional (3D) printed into scaffolds to promote osteointegration in rats, with an end goal of spine fusion without the need for recombinant growth factor. Spine fusion was evaluated by manual palpation, and osteointegration and de novo bone formation within scaffold struts were evaluated by laboratory and synchrotron microcomputed tomography and histology. The 3:1 HA:DBM composite achieved the highest mean fusion score and fusion rate (92%), which was significantly greater than the 3D printed DBM-only scaffold (42%). New bone was identified extending from the host transverse processes into the scaffold macropores, and osteointegration scores correlated with successful fusion. Strikingly, the combination of HA and DBM resulted in the growth of bone-like spicules within the DBM particles inside scaffold struts. These spicules were not observed in DBM-only scaffolds, suggesting that de novo spicule formation requires both HA and DBM. Collectively, our work suggests that this recombinant growth factor-free composite shows promise to overcome the limitations of currently used bone graft substitutes for spine fusion. Impact Statement Currently, there exists a no safe, yet highly effective, bone graft substitute that is well accepted for use in spine fusion procedures. With this work, we show that a three-dimensional printed scaffold containing osteoconductive hydroxyapatite and osteoinductive demineralized bone matrix that promotes new bone spicule formation, osteointegration, and successful fusion (stabilization) when implemented in a preclinical model of spine fusion. Our study suggests that this material shows promise as a recombinant growth factor-free bone graft substitute that could safely promote high rates of successful fusion and improve patient care.


Assuntos
Substitutos Ósseos/química , Impressão Tridimensional , Fusão Vertebral/métodos , Animais , Durapatita/química , Humanos , Ratos , Ratos Sprague-Dawley , Microtomografia por Raio-X
14.
Sports Med ; 49(8): 1275-1289, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31214979

RESUMO

OBJECTIVE: We performed a systematic review, meta-analysis and meta-regression of exercise studies that sought to determine the relationship between cardiac troponin (cTn) and left ventricular (LV) function. The second objective was to determine how study-level and exercise factors influenced the variation in the body of literature. DATA SOURCES: A systematic search of Pubmed Central, Science Direct, SPORTDISCUS and MEDLINE databases. ELIGIBILITY CRITERIA: Original research articles published between 1997 and 2018 involving > 30 mins of continuous exercise, measuring cardiac troponin event rates and either LV ejection fraction (LVEF) or the ratio of the peak early (E) to peak late (A) filling velocity (E/A ratio). DESIGN: Random-effects meta-analyses and meta-regressions with four a priori determined covariates (age, exercise heart rate [HR], duration, mass). REGISTRATION: The systematic search strategy was registered on the PROSPERO database (CRD42018102176). RESULTS: Pooled cTn event rates were evident in 45.6% of participants (95% confidence interval (CI) 33.6-58.2); however, the overall effect was non-significant (P > 0.05). There were significant (P < 0.05) reductions in E/A ratio of - 0.38 (SMD = - 1.2, 95% CI - 1.4 to - 1.0), and LVEF of - 2.02% (SMD = - 0.38, 95% CI - 0.7 to - 0.1) pre- to post-exercise. Increased exercise HR was a significant predictor of troponin release and E/A ratio. Participant age was negatively associated with cTn release. There was a significant negative association between E/A ratio with increased rates of cTn release (P < 0.05). CONCLUSIONS: High levels of statistical heterogeneity and methodological variability exist in the majority of EICF studies. Our findings show that exercise intensity and age are the most powerful determinants of cTn release. Diastolic function is influenced by exercise HR and cTn release, which implies that exercise bouts at high intensities are enough to elicit cTn release and reduce LV diastolic function. Future EICF studies should (1) utilise specific echocardiographic techniques such as myocardial speckle tracking, (2) ensure participants are euhydrated during post-exercise measurements, and (3) repeat measures in the hours following exercise to assess symptom progression or recovery. It is also recommended to further explore the relationship between aging, training history, and exercise intensity on cTn release and functional changes.


Assuntos
Exercício Físico , Troponina/sangue , Função Ventricular Esquerda , Fatores Etários , Biomarcadores/sangue , Humanos
15.
Ultrasound Obstet Gynecol ; 54(3): 344-349, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30381850

RESUMO

OBJECTIVE: Obesity is an increasing problem worldwide, with well recognized detrimental effects on cardiovascular health; however, very little is known about the effect of obesity on cardiovascular adaptation to pregnancy. The aim of the present study was to compare biventricular cardiac function at term between obese pregnant women and pregnant women with normal body weight, utilizing conventional echocardiography and speckle-tracking assessment. METHODS: This was a prospective case-control study of 40 obese, but otherwise healthy, pregnant women with a body mass index (BMI) of ≥ 35 kg/m2 and 40 healthy pregnant women with a BMI of ≤ 30 kg/m2 . All women underwent a comprehensive echocardiographic examination and speckle-tracking assessment at term. RESULTS: Obese pregnant women, compared with controls, had significantly higher systolic blood pressure (117 vs 109 mmHg; P = 0.002), cardiac output (6.73 vs 4.90 L/min; P < 0.001), left ventricular (LV) mass index (74 vs 64 g/m2 ; P < 0.001) and relative wall thickness (0.43 vs 0.37; P < 0.001). Diastolic dysfunction was present in five (12.5%) controls and 16 (40%) obese women (P = 0.004). In obese women, compared with controls, LV global longitudinal strain (-15.59 vs -17.61%; P < 0.001), LV endocardial (-17.30 vs -19.84%; P < 0.001) and epicardial (-13.10 vs -15.73%; P < 0.001) global longitudinal strain as well as LV early diastolic strain rate (1.05 vs 1.24 /s; P = 0.006) were all significantly reduced. No differences were observed in the degree of LV twist and torsion between the two groups. CONCLUSIONS: Morbidly obese, but otherwise healthy, pregnant women at term had significant LV hypertrophy with evidence of diastolic dysfunction and impaired deformation indices compared with pregnant women of normal weight. These findings are likely to represent a maladaptive response of the heart to volume overload in obese pregnancy. The impact of theses changes on pregnancy outcome and long-term maternal outcome is unclear. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Débito Cardíaco , Obesidade/fisiopatologia , Complicações Cardiovasculares na Gravidez/fisiopatologia , Gestantes , Adulto , Peso ao Nascer , Índice de Massa Corporal , Estudos de Casos e Controles , Ecocardiografia , Feminino , Hemodinâmica , Humanos , Obesidade/complicações , Valor Preditivo dos Testes , Gravidez , Complicações Cardiovasculares na Gravidez/diagnóstico por imagem , Resultado da Gravidez , Estudos Prospectivos , Valores de Referência
16.
Pregnancy Hypertens ; 13: 198-203, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30177052

RESUMO

OBJECTIVES: To study biventricular cardiac changes with conventional echocardiography and new echocardiographic speckle tracking technologies such strain, twist and torsion in pregnant women with preeclampsia at term and normotensive control term pregnant women. STUDY DESIGN: For this prospective single centre case-control study, we consecutively recruited 30 women with preeclampsia at term as cases and 40 healthy control term pregnant women. All women underwent transthoracic echocardiographic examination at the time point of inclusion into the study. MAIN OUTCOME MEASURES: Signs of systolic and/or diastolic cardiac maladaptation to the increased volume load associated with pregnancy. RESULTS: Conventional echocardiography revealed mild left sided diastolic impairment in the form of significantly increased E/E' in preeclampsia (7.58 ±â€¯1.72 vs. 6.18 ±â€¯1.57, p = 0.001) compared to normotensive controls, but no evidence of systolic impairment. With speckle tracking analysis, significant decreases in left ventricular global (-13.32 ±â€¯2.37% vs. -17.61 ±â€¯1.89%, p < 0.001), endocardial (-15.64 ±â€¯2.79% vs. -19.84 ±â€¯2.35%, p < 0.001) and epicardial strain (-11.48 ±â€¯2.15% vs. -15.73 ±â€¯1.66%, p < 0.001) as well as left ventricular longitudinal strain rate (-0.84 ±â€¯0.14 s-1 vs. -0.98 ±â€¯0.12 s-1, p < 0.001) and left ventricular early diastolic strain rate (0.86 ±â€¯0.30 s-1 vs. 1.24 ±â€¯0.26 s-1, p < 0.001) could be observed in women with term preeclampsia. CONCLUSIONS: The findings of this study demonstrate that pregnant women with term preeclampsia with minimal functional changes on conventional echocardiography, demonstrated significant subclinical myocardial changes on speckle tracking analysis.


Assuntos
Pressão Sanguínea , Contração Miocárdica , Pré-Eclâmpsia/fisiopatologia , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda , Adaptação Fisiológica , Adulto , Doenças Assintomáticas , Fenômenos Biomecânicos , Estudos de Casos e Controles , Ecocardiografia , Feminino , Humanos , Pré-Eclâmpsia/diagnóstico por imagem , Gravidez , Estudos Prospectivos , Fatores de Risco , Torção Mecânica , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia , Função Ventricular Direita
17.
Nanoscale ; 10(17): 8187-8195, 2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29676427

RESUMO

An outstanding current carrying performance (namely critical current density, Jc) over a broad temperature range of 10-77 K for magnetic fields up to 12 T is reported for films of YBa2Cu3O7-x with Ba2Y(Nb,Ta)O6 inclusion pinning centres (YBCO-BYNTO) and thicknesses in the range of 220-500 nm. Jc values of 10 MA cm-2 were measured at 30 K - 5 T and 10 K - 9 T with a corresponding maximum of the pinning force density at 10 K close to 1 TN m-3. The system is very flexible regarding properties and microstructure tuning, and the growth window for achieving a particular microstructure is wide, which is very important for industrial processing. Hence, the dependence of Jc on the magnetic field angle was readily controlled by fine tuning the pinning microstructure. Transmission electron microscopy (TEM) analysis highlighted that higher growth rates induce more splayed and denser BYNTO nanocolumns with a matching field as high as 5.2 T. Correspondingly, a strong peak at the B||c-axis is noticed when the density of vortices is lower than the nanocolumn density. YBCO-BYNTO is a very robust and reproducible composite system for high-current coated conductors over an extended range of magnetic fields and temperatures.

18.
Clin Microbiol Infect ; 24(10): 1051-1054, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29505879

RESUMO

SCOPE: Clostridium difficile infection (CDI) is the most important infective cause of healthcare-associated diarrhoea in high income countries and one of the most important healthcare-associated pathogens in both Europe and the United States. It is associated with high morbidity and mortality resulting in both societal and financial burden. A significant proportion of this burden is potentially preventable by a combination of targeted infection prevention and control measures and antimicrobial stewardship. The aim of this guidance document is to provide an update on recommendations for prevention of CDI in acute care settings to provide guidance to those responsible for institutional infection prevention and control programmes. METHODS: An expert group was set up by the European society of clinical microbiology and infectious diseases (ESCMID) Study Group for C. difficile (ESGCD), which performed a systematic review of the literature on prevention of CDI in adults hospitalized in acute care settings and derived respective recommendations according to the GRADE approach. Recommendations are stratified for both outbreak and endemic settings. QUESTIONS ADDRESSED BY THE GUIDELINE AND RECOMMENDATIONS: This guidance document provides thirty-six statements on strategies to prevent CDI in acute care settings, including 18 strong recommendations. No recommendation was provided for three questions.


Assuntos
Clostridioides difficile/patogenicidade , Infecções por Clostridium/prevenção & controle , Infecção Hospitalar/prevenção & controle , Atenção à Saúde/normas , Diarreia/prevenção & controle , Surtos de Doenças/prevenção & controle , Europa (Continente) , Humanos , Estados Unidos
19.
Min Eng ; 70(1): 35-41, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29416179

RESUMO

Tests were conducted to determine properties of four foam agents for their potential use in longwall mining dust control. Foam has been tried in underground mining in the past for dust control and is currently being reconsidered for use in underground coal longwall operations in order to help those operations comply with the Mine Safety and Health Administration's lower coal mine respirable dust standard of 1.5 mg/m3. Foams were generated using two different methods. One method used compressed air and water pressure to generate foam, while the other method used low-pressure air generated by a blower and water pressure using a foam generator developed by the U.S. National Institute for Occupational Safety and Health. Foam property tests, consisting of a foam expansion ratio test and a water drainage test, were conducted to classify foams. Compressed-air-generated foams tended to have low expansion ratios, from 10 to 19, with high water drainage. Blower-air-generated foams had higher foam expansion ratios, from 30 to 60, with lower water drainage. Foams produced within these ranges of expansion ratios are stable and potentially suitable for dust control. The test results eliminated two foam agents for future testing because they had poor expansion ratios. The remaining two foam agents seem to have properties adequate for dust control. These material property tests can be used to classify foams for their potential use in longwall mining dust control.

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