Sex and Gender Differences in Ischemic Heart Disease: Endocrine Vascular Disease Approach (EVA) Study Design

Improvements in ischemic heart disease (IHD) management have been unbalanced between sexes, with coronary microvascular dysfunction considered the likely underlying reason. The Endocrine Vascular disease Approach (EVA) is an observational study ( Clinicaltrial.gov NCT02737982) aiming to assess sex and gender interactions between coronary circulation, sexual hormones, and platelet function. Consecutive patients with IHD undergoing coronary angiography will be recruited: (1) to assess sex and gender differences in angiographic reperfusion indexes; (2) to evaluate the effects of estrogen/androgen on sex-related differences in myocardial ischemia; (3) to investigate the platelet biology differences between men and women with IHD; (4) to verify sex- and gender-driven interplay between response to percutaneous coronary intervention, platelets, sex hormones, and myocardial damage at baseline and its impact on 12-month outcomes. The integration of sex and gender in this translational project on IHD will contribute to the identification of new targets for further innovative clinical interventions

An aerostatic pad with an internal pressure control

Because of their almost zero friction and wear, aerostatic pads are widely used in applications where very precise positioning is required. However, this kind of bearing suffers from poor damping and low specific stiffness. This paper presents a new compensation strategy to increase air pad stiffness. This method exploits a custom-built pneumatic valve which can be easily integrated with any commercial pad. The design and the working principle of the proposed system are described and studied with the aid of a lumped parameter model. The effectiveness of the proposed compensation is numerically and experimentally evaluated. The results demonstrate that the solution represents a good and cost-effective method to enhance the static stiffness of aerostatic pads

Unbalance Response Analysis of a Spindle Supported on Gas Bearings: A Comparison between Different Approaches

Gas journal bearings are widely employed in high-speed spindles for the micromachining industry. Compared to their oil and rolling counterparts, gas bearings have a longer life span, lower friction and a lower level of noise. In order to design accurate high-speed spindles supported by externally pressurized gas bearings, it is vital to analyze the characteristics of rotor bearing systems. In this paper, we present an analysis of the unbalance response of a high-speed spindle supported by gas journal bearings. A number of aspects to enhance the accuracy of the system are discussed. We performed the analysis by considering a nonlinear and a linearized numerical model validated through experimental measurements

Air Pad Controlled by Means of a Diaphragm-Valve: Static and Dynamic Behaviour

This paper presents the analysis of the static and dynamic performance of a passively compensated air pad. The proposed method consists in the integration of a custom-built diaphragm valve and a commercial aerostatic pad. A lumped model is used to simulate the static and dynamic performance of the pad. Results demonstrate that the proposed method is very effective when the system works with excitation frequencies below 10 Hz

On the Design of a Diaphragm Valve for Aerostatic Bearings

Because of their almost zero friction, cleanness and long life, aerostatic bearings are commonly used in many applications where high precision of positioning is required, e.g. machine tools, measuring machines, semiconductor manufacturing and power board testing. However, air bearings suffer from low relative stiffness and poor damping. Active and passive compensation are two effective methods to enhance the static and dynamic performance of these kinds of bearings. Despite their higher performance, active compensation solutions are too expensive to be used in industrial applications, as a consequence of the costs related to their controllers, actuators and sensors. This paper presents the design and performance of a passive compensation method that exploits a diaphragm valve. Thanks to its ease of integration, satisfactory performance and relatively low cost, this method could be a valuable solution to increasing the stiffness of aerostatic bearings. This work provides a procedure to design diaphragm valves depending on the type of the integrated pad and the desired nominal air gap height. Results demonstrate that, once correctly designed, the diaphragm valve makes it possible to obtain bearings with quasi-static infinite stiffness at the selected air gap height

Glutathione infusion before primary percutaneous coronary intervention: A randomised controlled pilot study

Objective: In the setting of reperfused ST-elevation myocardial infarction (STEMI), increased production of reactive oxygen species (ROS) contributes to reperfusion injury. Among ROS, hydrogen peroxide (H2O2) showed toxic effects on human cardiomyocytes and may induce microcirculatory impairment. Glutathione (GSH) is a water-soluble tripeptide with a potent oxidant scavenging activity. We hypothesised that the infusion of GSH before acute reoxygenation might counteract the deleterious effects of increased H2O2 generation on myocardium. Methods: Fifty consecutive patients with STEMI, scheduled to undergo primary angioplasty, were randomly assigned, before intervention, to receive an infusion of GSH (2500 mg/25 mL over 10 min), followed by drug administration at the same doses at 24, 48 and 72 hours elapsing time or placebo. Peripheral blood samples were obtained before and at the end of the procedure, as well as after 5 days. H2O2 production, 8-iso-prostaglandin F2α (PGF2α) formation, H2O2 breakdown activity (HBA) and nitric oxide (NO) bioavailability were determined. Serum cardiactroponin T (cTpT) was measured at admission and up to 5 days. Results: Following acute reperfusion, a significant reduction of H2O2 production (p=0.0015) and 8-iso-PGF2α levels (p=0.0003), as well as a significant increase in HBA (p<0.0001)and NO bioavailability (p=0.035), was found in the GSH group as compared with placebo. In treated patients, attenuated production of H2O2 persisted up to 5 days from the index procedure (p=0.009) and these changes was linked to those of the cTpT levels (r=0.41, p=0.023). Conclusion: The prophylactic and prolonged infusion of GSH seems to determine a rapid onset and persistent blunting of H2O2 generation improving myocardial cell survival. Nevertheless, a larger trial, adequately powered for evaluation of clinical endpoints, is ongoing to confirm the current finding

Young Women With Acute Myocardial Infarction: Risk Prediction Model for 1-Year Hospital Readmission

Background Although young women ( aged ≤ 55 years) are at higher risk than similarly aged men for hospital readmission within 1 year after an acute myocardial infarction (AMI), no risk prediction models have been developed for them. The present study developed and internally validated a risk prediction model of 1-year post-AMI hospital readmission among young women that considered demographic, clinical, and gender-related variables. Methods We used data from the US Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients (VIRGO) study (n = 2007 women), a prospective observational study of young patients hospitalized with AMI. Bayesian model averaging was used for model selection and bootstrapping for internal validation. Model calibration and discrimination were respectively assessed with calibration plots and area under the curve. Results Within 1-year post-AMI, 684 women (34.1%) were readmitted to the hospital at least once. The final model predictors included: any in-hospital complication, baseline perceived physical health, obstructive coronary artery disease, diabetes, history of congestive heart failure, low income ( < $30,000 US), depressive symptoms, length of hospital stay, and race (White vs Black). Of the 9 retained predictors, 3 were gender-related. The model was well calibrated and exhibited modest discrimination (area under the curve = 0.66). Conclusions Our female-specific risk model was developed and internally validated in a cohort of young female patients hospitalized with AMI and can be used to predict risk of readmission. Whereas clinical factors were the strongest predictors, the model included several gender-related variables (ie, perceived physical health, depression, income level). However, discrimination was modest, indicating that other unmeasured factors contribute to variability in hospital readmission risk among younger women

Impact of biological sex and gender-related factors on public engagement in protective health behaviours during the COVID-19 pandemic: cross-sectional analyses from a global survey

Objective Given the role of sociocultural gender in shaping human behaviours, the main objective of this study was to examine whether sex and gender-related factors were associated with the public’s adherence to COVID-19-recommended protective health behaviours. Design This was a retrospective analysis of the survey that captured data on people’s awareness, attitudes and behaviours as they relate to the COVID-19 policies. Setting Data from the International COVID-19 Awareness and Responses Evaluation survey collected between March 2020 and February 2021 from 175 countries. Participants Convenience sample around the world. Main outcome measures We examined the role of sex and gender-related factors in relation to non-adherence of protective health behaviours including: (1) hand washing; (2) mask wearing; and (3) physical distancing. Multivariable logistic regression was conducted to determine the factors associated with non-adherence to behaviours. Results Among 48 668 respondents (mean age: 43 years; 71% female), 98.3% adopted hand washing, 68.5% mask wearing and 76.9% physical distancing. Compared with males, females were more likely to adopt hand washing (OR=1.97, 95% CI: 1.71 to 2.28) and maintain physical distancing (OR=1.28, 95% CI: 1.22 to 1.34). However, in multivariable sex-stratified models, females in countries with higher Gender Inequality Indexes (GII) were less likely to report hand washing (adjusted OR (aOR)=0.47, 95% CI: 0.21 to 1.05). Females who reported being employed (aOR=0.22, 95% CI: 0.10 to 0.48) and in countries with low/medium GIIs (aOR=0.18, 95% CI 0.06 to 0.51) were less likely to report mask wearing. Females who reported being employed were less likely to report physical distancing (aOR=0.39, 95% CI: 0.32 to 0.49). Conclusion While females showed greater adherence to COVID-19 protective health behaviours, gender-related factors, including employment status and high country-wide gender inequality, were independently associated with non-adherence. These findings may inform public health and vaccination policies in current as well as future pandemics

Prognostic significance of adiponectin levels in non-metastatic colorectal cancer

Circulating adiponectin levels are inversely correlated with the risk of colorectal cancer (CRC). This study was designed to evaluate the association between adiponectin levels and the clinicopathological variables of CRC and to analyze the possible prognostic value of adiponectin in predicting relapse-free survival