Suchergebnisse

Corneal mechanical changes are believed to occur before any visible structural alterations observed during routine clinical evaluation. This study proposed developing an elastography technique based on torsional waves (TWE) adapted to the specificities of the cornea. By measuring the displacements in the propagation plane perpendicular to the axis of the emitter, the effect of guided waves in platelike media was proven negligible. Ex vivo experiments were carried out on porcine corneal samples considering a group of control and one group of alkali burn treatment ( NH 4OH) that modified the mechanical properties. Phase speed was recovered as a function of intraocular pressure (IOP), and a Kelvin-Voigt rheological model was fitted to the dispersion curves to estimate viscoelastic parameters. A comparison with uniaxial tensile testing with thin-walled assumptions was also performed. Both shear elasticity and viscosity correlated positively with IOP, being the elasticity lower and the viscosity higher for the treated group. The viscoelastic parameters ranged from 21.33 to 63.17 kPa, and from 2.82 to 5.30 Pa s, for shear elasticity and viscosity, respectively. As far as the authors know, no other investigations have studied this mechanical plane under low strain ratios, typical of dynamic elastography in corneal tissue. TWE reflected mechanical properties changes after treatment, showing a high potential for clinical diagnosis due to its rapid performance time and paving the way for future in vivo studies. ; Ministerio de Educacion, Cultura y Deporte Grant DPI2017-83859-R DPI2014-51870-R UNGR15-CE-3664 EQC2018-004508-P ; Spanish Government DTS15/00093 PI16/00339 ; Instituto de Salud Carlos III y Fondos Feder ; Junta de Andalucia PI-0107-2017 PIN-0030-2017 IE2017-5537 ; MCIN/AEI - European Social Fund "Investing in your future" PRE2018-086085 ; Consejeria de economia, conocimiento, empresas y universidad SOMM17/6109/UGR B-TEP-026- IE2017-5537 P18-RT-1653 ; European Commission SOMM17/6109/UGR B-TEP-026- IE2017-5537 ...

This study was supported by research grants from CIBER de Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III, Spain (PI16/01858, PI18/01573, PI20/01568), co-funded by European Union (ERDF), "A way to make Europe". ; Supplementary data to this article can be found online at https://doi. org/10.1016/j.envint.2021.106734 ; Background Despite restrictions on their production and use, most of the population is still exposed to Persistent Organic Pollutants (POPs), including organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). These chemicals are thought to contribute to the aetiology of highly prevalent chronic conditions, such as cardiovascular diseases (CVDs), although current evidences are still controversial. Objectives To explore the potential contribution of historical POP exposure to 15-year pharmaceutical consumption in relation to CVD. Methods This study is framed within GraMo adult cohort. Participants (n = 387) were recruited in two hospitals in Granada province, Southern Spain (2003–2004). Historical exposure to 5 OCPs and 3 non-dioxine-like PCBs was estimated by analysing adipose tissue concentrations at recruitment. Pharmaceutical consumption from recruitment until year 2017 was quantified by reviewing dispensation databases. Average consumption increase (ACI) in CVD medication was calculated by subtracting average consumption in 2002 to the average yearly consumption during follow-up. ACI was expressed as Defined Daily Dose (DDD)/year units. Data analyses were carried out using a multivariable multinomial logistic regression and weighted quantile sum regression (WQS), with ACI categorized in quartiles (Q) as the dependent variable. Results Concentrations of most pollutants showed a positive trend with the quartiles of ACI. Particularly, PCB-153 showed increasing and statistically significant odds ratios (ORs) for Q2 (OR: 1.27, 95% confidence interval (CI): 1.07–1.52), Q3 (OR: 1.49, 95 %CI: 1.17–1.88) and Q4 (OR: 1.42, 95 %CI: 1.13–1.78) vs Q1. Similarly, beta-hexachlorocyclohexane (β-HCH) also showed increasing ORs, that reached statistical significance in Q4 (OR: 1.36, 95 %CI: 1.06–1.74) vs Q1. These findings were corroborated by WQS analyses, that revealed a significant mixture effect, predominantly accounted for by PCB-153 and β-HCH. Discussion Our results suggest that long-term POP exposure might represent a modifiable risk factor for CVD. These findings are relevant for public health campaigns and management, since pharmaceutical consumption is considered an indicator of both morbidity and health expenditure. ; CIBER de Epidemiología y Salud Pública ; Santa Ana and San Cecilio Hospitals RYC-2016-20155 ; European Commission ; Instituto de Salud Carlos III PI16/01858, PI18/01573, PI20/01568 ISCIII Ministerio de Economía, Industria y Competitividad, Gobierno de España ; European Regional Development Fund ; Ministerio de Economía, Industria y Competitividad, Gobierno de España