93 research outputs found

    Oestradiol levels and superoxide dismutase activity in age-related cataract: a case-control study.

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    Background: It has been suggested that the higher prevalence of cataract in women is caused by a withdrawal effect of oestrogen at menopause. In vitro studies have demonstrated protection of serum oestradiol (E2) against oxidative stress through upregulation of antioxidant enzymes, including superoxide dismutase (SOD). The purpose of the present study was to investigate E2 levels and SOD erythrocyte activity in patients with age-related cataract. Methods: The studied subjects consisted of 103 patients with age-related cataract and 22 controls. Cataracts were classified as nuclear, cortical, or posterior subcapsular. Blood samples were collected and data on smoking, hormonal use, diabetes and age at menarche/menopause was obtained for all individuals. Serum oestradiol analyses were performed with radioimmunoassay (RIA) and SOD activity was measured in erythrocyte lysates. Results: A negative correlation between age and E2 concentration was seen in a linear regression analysis. No correlation was seen between SOD activity and age or gender and no correlation between E2 levels and SOD activity was found using multiple linear regression. The mean level of E2 for all male subjects was 50.1 +/- 16.3 pmol/L, significantly higher compared to 13.8 +/- 11.8 pmol/L for postmenopausal women. Conclusion: The present study does not support a role for E2-induced effects on SOD in cataract formation. The findings of higher E2 levels in men than in postmenopausal women may suggest that decreased oestrogen at menopause is partially responsible for the gender-related difference in cataract prevalence. However, the latter can only be verified through prospective randomized trials using hormonal replacement therapy

    Antioxidant airway responses following experimental exposure to wood smoke in man

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    Background: Biomass combustion contributes to the production of ambient particulate matter (PM) in rural environments as well as urban settings, but relatively little is known about the health effects of these emissions. The aim of this study was therefore to characterize airway responses in humans exposed to wood smoke PM under controlled conditions. Nineteen healthy volunteers were exposed to both wood smoke, at a particulate matter (PM2.5) concentration of 224 +/- 22 mu g/m(3), and filtered air for three hours with intermittent exercise. The wood smoke was generated employing an experimental set-up with an adjustable wood pellet boiler system under incomplete combustion. Symptoms, lung function, and exhaled NO were measured over exposures, with bronchoscopy performed 24 h post-exposure for characterisation of airway inflammatory and antioxidant responses in airway lavages. Results: Glutathione (GSH) concentrations were enhanced in bronchoalveolar lavage (BAL) after wood smoke exposure vs. air (p = 0.025), together with an increase in upper airway symptoms. Neither lung function, exhaled NO nor systemic nor airway inflammatory parameters in BAL and bronchial mucosal biopsies were significantly affected. Conclusions: Exposure of healthy subjects to wood smoke, derived from an experimental wood pellet boiler operating under incomplete combustion conditions with PM emissions dominated by organic matter, caused an increase in mucosal symptoms and GSH in the alveolar respiratory tract lining fluids but no acute airway inflammatory responses. We contend that this response reflects a mobilisation of GSH to the air-lung interface, consistent with a protective adaptation to the investigated wood smoke exposure

    Anesthesia techniques and the risk of complications as reflected in the European Registry of Quality Outcomes for Cataract and Refractive Surgery

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    Purpose: To determine the trends in anesthesia techniques for cataract surgery over the past decade and their relationship to surgical complications. Setting: Clinics affiliated with the European Registry of Quality Outcomes for Cataract and Refractive Surgery (EUREQUO). Design: Retrospective cross-sectional register-based study. Methods: Variables include patient demographics, visual acuity, ocular comorbidities, surgery characteristics, intraoperative complications, and postoperative complications for the study period from January 2008, to December 2018. The anesthesia methods registered in the EUREQUO and included in the study are topical, combined topical and intracameral, sub-Tenon, regional, and general anesthesia. Multivariate logistic regression models for each complication were constructed to estimate the adjusted odds ratio (OR) and 95% CIs. Results: Complete data were available of 1 354 036 cataract surgeries. Topical anesthesia increased significantly over time (from 30% to 76%, P < .001). Sub-Tenon and regional anesthesia decreased (from 27% and 38% to 16% and 6%, respectively, P < .001), and general and combined topical and intracameral anesthesia remained stable (around 2%). Sub-Tenon (OR, 0.80; 95% CI, 0.71-0.91, P < .001), regional (0.74; 95% CI, 0.71-0.78, P < .001), general (0.53; 95% CI, 0.50-0.56, P < .001), and intracameral anesthesia (0.76; 95% CI, 0.64-0.90, P = .001) carried a significantly decreased risk of posterior capsule rupture (PCR), with and without dropped nucleus, compared with topical anesthesia. The risk of endophthalmitis was significantly lower with regional anesthesia compared with topical anesthesia (OR, 0.60; 95% CI, 0.44-0.82, P = .001). Conclusions: The use of topical anesthesia for cataract surgery increased over time. Topical anesthesia is associated with an increased risk of PCR with and without dropped nucleus, and endophthalmitis

    Development of machine learning models to predict posterior capsule rupture based on the EUREQUO registry

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    Purpose: To evaluate the performance of different probabilistic classifiers to predict posterior capsule rupture (PCR) prior to cataract surgery. Methods: Three probabilistic classifiers were constructed to estimate the probability of PCR: a Bayesian network (BN), logistic regression (LR) model, and multi‐layer perceptron (MLP) network. The classifiers were trained on a sample of 2 853 376 surgeries reported to the European Registry of Quality Outcomes for Cataract and Refractive Surgery (EUREQUO) between 2008 and 2018. The performance of the classifiers was evaluated based on the area under the precision‐recall curve (AUPRC) and compared to existing scoring models in the literature. Furthermore, direct risk factors for PCR were identified by analysing the independence structure of the BN. Results: The MLP network predicted PCR overall the best (AUPRC 13.1 ± 0.41%), followed by the BN (AUPRC 8.05 ± 0.39%) and the LR model (AUPRC 7.31 ± 0.15%). Direct risk factors for PCR include preoperative best‐corrected visual acuity (BCVA), year of surgery, operation type, anaesthesia, target refraction, other ocular comorbidities, white cataract, and corneal opacities. Conclusions: Our results suggest that the MLP network performs better than existing scoring models in the literature, despite a relatively low precision at high recall. Consequently, implementing the MLP network in clinical practice can potentially decrease the PCR rate

    Photocatalytic Decomposition of Formic Acid on Mo2C-Containing Catalyst

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    Soluble components in the peripheral blood from experimental exposure of 14 healthy subjects to filtered air and wood smoke. Samples were collected before (pre), at 24 h and 44 h after exposure, to air and wood smoke. Data are given as medians with interquartile range. (DOCX 62 kb
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