Mechanical properties of multi-walled carbon nanotube/epoxy composites

Untreated and acid-treated multi-walled carbon nanotubes (MWNT) were used to fabricate MWNT/epoxy composite samples by sonication technique. The effect of MWNT addition and their surface modification on the mechanical properties were investigated. Modified Halpin-Tasi equation was used to evaluate the Young's modulus and tensile strength of the MWNT/epoxy composite samples by the incorporation of an orientation as well as an exponential shape factor in the equation. There was a good correlation between the experimentally obtained Young's modulus and tensile strength values and the modified Halpin-Tsai theory. The fracture surfaces of MWNT/epoxy composite samples were analyzed by scanning electron microscope

The malignant epidemic-changing patterns of trauma

Objectives and Setting. The worldwide burden of trauma is increasing, but is unequally distributed between nations. Trauma in South Africa targets the young and productive in society and imposes a major burden on the health infrastructure. We undertook a review of injury trends among patients attending the Johannesburg Hospital Trauma Unit (JHTU) and the Johannesburg Medicolegal Laboratory (JMLL) in order to document the evolution in patterns of trauma over a 17-year period of great social and political change. Design, subjects and outcome measures. This was a retrospective review of all priority-one patients attending the JHTU from January 1985 to December 2001. The JHTU trauma database was used to retrieve information on patient demographics, wound mechanism and injury severity. The database at the JMLL, maintained since 1996, was examined and the manner and place of death were analysed.Results. The JHTU has seen an unprecedented increase in the number of trauma patients over the last 17 years. The patients' demographic profiles have altered and injury is now predominantly due to interpersonal violence. Unnatural deaths examined at the JMLL have declined by 19% since 1996; however, the proportion of those deaths due to gunshot wounds has risen.Conclusions. The social and political changes in South Africa in recent years have led to changes in the injury profiles seen at the JHTU. Part of the increase can be explained by desegregation and a reduction in the provision of local hospital services; however, the impact of urbanisation within South Africa, cross-border migration and the high incidence of substance abuse are recognised. Evidence supports the implementation of legislative, environmental, social and behavioural interventions to contain and reduce the incidence and impact of violence and injury. Concerted efforts must be made at all levels to curb South Africa's  trauma  epidemic

Diabetic cardiomyopathy

Diabetic cardiomyopathy is a distinct primary disease process, independent of coronary artery disease, which leads to heart failure in diabetic patients. Epidemiological and clinical trial data have confirmed the greater incidence and prevalence of heart failure in diabetes. Novel echocardiographic and MR (magnetic resonance) techniques have enabled a more accurate means of phenotyping diabetic cardiomyopathy. Experimental models of diabetes have provided a range of novel molecular targets for this condition, but none have been substantiated in humans. Similarly, although ultrastructural pathology of the microvessels and cardiomyocytes is well described in animal models, studies in humans are small and limited to light microscopy. With regard to treatment, recent data with thiazoledinediones has generated much controversy in terms of the cardiac safety of both these and other drugs currently in use and under development. Clinical trials are urgently required to establish the efficacy of currently available agents for heart failure, as well as novel therapies in patients specifically with diabetic cardiomyopathy

Recurrent Pregnancy Loss in a Subject with Heterozygote Factor V Leiden Mutation; a Case Report

Recurrent pregnancy loss is usually defined as the loss of two or more consecutive pregnancies before 20 weeks of gestation, which occurs in approximately 5% of reproductive-aged women. It has been suggested that women with thrombophilia have an increased risk of pregnancy loss and other adverse pregnancy outcomes. Thrombophilia is an important predisposition to blood clot formation and is considered as a significant risk factor for recurrent pregnancy loss. The inherited predisposition to thrombophilia is most often associated with factor V Leiden mutation, prothrombin G20210A mutation, and methylenetetrahydrofolate reductase C677T and A1298C gene variants. The net effect is an increased cleavage of prothrombin to thrombin and excessive blood coagulation

‘Super Rehab’: can we achieve coronary artery disease regression? A feasibility study protocol

Introduction Patients diagnosed with coronary artery disease (CAD) are currently treated with medications and lifestyle advice to reduce the likelihood of disease progression and risk of future major adverse cardiovascular events (MACE). Where obstructive disease is diagnosed, revascularisation may be considered to treat refractory symptoms. However, many patients with coexistent cardiovascular risk factors, particularly those with metabolic syndrome (MetS), remain at heightened risk of future MACE despite current management.Cardiac rehabilitation is offered to patients post-revascularisation, however, there is no definitive evidence demonstrating its benefit in a primary prevention setting. We propose that an intensive lifestyle intervention (Super Rehab, SR) incorporating high-intensity exercise, diet and behavioural change techniques may improve symptoms, outcomes, and enable CAD regression.This study aims to examine the feasibility of delivering a multicentre randomised controlled trial (RCT) testing SR for patients with CAD, in a primary prevention setting.Methods and analysis This is a multicentre randomised controlled feasibility study of SR versus usual care in patients with CAD. The study aims to recruit 50 participants aged 18–75 across two centres. Feasibility will be assessed against rates of recruitment, retention and, in the intervention arm, attendance and adherence to SR. Qualitative interviews will explore trial experiences of study participants and practitioners. Variance of change in CAD across both arms of the study (assessed with serial CT coronary angiography) will inform the design and power of a future, multi-centre RCT.Ethics and dissemination Ethics approval was granted by South West—Frenchay Research Ethics Committee (reference: 21/SW/0153, 18 January 2022). Study findings will be disseminated via presentations to relevant stakeholders, national and international conferences and open-access peer-reviewed research publications.Trial registration number ISRCTN14603929

Validation of the MIRACLE 2 Score for Prognostication After Out-of-hospital Cardiac Arrest.

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is associated with very poor clinical outcomes. An optimal pathway of care is yet to be defined, but prognostication is likely to assist in the challenging decision-making required for treatment of this high-risk patient cohort. The MIRACLE 2 score provides a simple method of neuro-prognostication but as yet it has not been externally validated. The aim of this study was therefore to retrospectively apply the score to a cohort of OHCA patients to assess the predictive ability and accuracy in the identification of neurological outcome. METHODS: Retrospective data of patients identified by hospital coding, over a period of 18 months, were collected from a large tertiary-level cardiac centre with a mature, multidisciplinary OHCA service. MIRACLE 2 score performance was assessed against three existing OHCA prognostication scores. RESULTS: Patients with all-comer OHCA, of presumed cardiac origin, with and without evidence of ST-elevation MI (43.4% versus 56.6%, respectively) were included. Regardless of presentation, the MIRACLE 2 score performed well in neuro-prognostication, with a low MIRACLE 2 score (≤2) providing a negative predictive value of 94% for poor neurological outcome at discharge, while a high score (≥5) had a positive predictive value of 95%. A high MIRACLE 2 score performed well regardless of presenting ECG, with 91% of patients receiving early coronary angiography having a poor outcome. CONCLUSION: The MIRACLE 2 score has good prognostic performance and is easily applicable to cardiac-origin OHCA presentation at the hospital front door. Prognostic scoring may assist decision-making regarding early angiographic assessment. </p

Time to TAVI: streamlining the pathway to treatment

Introduction Severe aortic stenosis is a major cause of morbidity and mortality. The existing treatment pathway for transcatheter aortic valve implantation (TAVI) traditionally relies on tertiary Heart Valve Centre workup. However, this has been associated with delays to treatment, in breach of British Cardiovascular Intervention Society targets. A novel pathway with emphasis on comprehensive patient workup at a local centre, alongside close collaboration with a Heart Valve Centre, may help reduce the time to TAVI.Methods The centre performing local workup implemented a novel TAVI referral pathway. Data were collected retrospectively for all outpatients referred for consideration of TAVI to a Heart Valve Centre from November 2020 to November 2021. The main outcome of time to TAVI was calculated as the time from Heart Valve Centre referral to TAVI, or alternative intervention, expressed in days. For the centre performing local workup, referral was defined as the date of multidisciplinary team discussion. For this centre, a total pathway time from echocardiographic diagnosis to TAVI was also evaluated. A secondary outcome of the proportion of referrals proceeding to TAVI at the Heart Valve Centre was analysed.Results Mean±SD time from referral to TAVI was significantly lower at the centre performing local workup, when compared with centres with traditional referral pathways (32.4±64 to 126±257 days, p&lt;0.00001). The total pathway time from echocardiographic diagnosis to TAVI for the centre performing local workup was 89.9±67.6 days, which was also significantly shorter than referral to TAVI time from all other centres (p&lt;0.003). Centres without local workup had a significantly lower percentage of patients accepted for TAVI (49.5% vs 97.8%, p&lt;0.00001).Discussion A novel TAVI pathway with emphasis on local workup within a non-surgical centre significantly reduced both the time to TAVI and rejection rates from a Heart Valve Centre. If adopted across the other centres, this approach may help improve access to TAVI