The left atrial appendage in health and disease

Atrial fibrillation (AF) is the commonest sustained cardiac arrhythmiaand results in significant morbidity and mortality. The left atrial appendage (LAA), a small embryonic remnant of the left atrium (LA), has been shown to play a key role in the pathophysiology of AF-related stroke and thromboembolism. As a consequence the LAA, in spite of its meagre size, has been described as ‘our most lethal human attachment’. Despite being a recognised harbinger of disease, the LAA has also been shown to play an important role in health. This review seeks to address our current understanding of this vital structure in both health and disease states

Disseminated peritoneal hydatidosis following blunt abdominal trauma: A case report

A middle age lady presented with abdominal pain was diagnosed to have multiple peritoneal and hepatic hydatid cysts on CT scan. Retrospectively she was found to have suffered blunt abdominal trauma

Exposure to Mimivirus collagen promotes arthritis

Collagens, the most abundant proteins in animals, also occur in some recently described nucleocytoplasmic large DNA viruses such as Mimiviridae, which replicate in amoebae. To clarify the impact of viral collagens on the immune response of animals exposed to Mimiviridae, we have investigated the localization of collagens in Acanthamoeba polyphaga mimivirus particles and the response of mice to immunization with mimivirus particles. Using protein biotinylation, we have first shown that viral collagen encoded by the ORF L71 is present at the surface of mimivirus particles. Exposure to mimivirus collagens elicited the production of anti-collagen antibodies in DBA/1 mice immunized intra-dermally with mimivirus protein extracts. This antibody response also targeted mouse collagen type II and was accompanied by T-cell reactivity to collagen and joint inflammation as observed in collagen-induced arthritis following immunization of mice with bovine collagen type II. The broad distribution of nucleocytoplasmic large DNA viruses in the environment suggests that humans are constantly exposed to such large virus particles. A survey of blood sera from human healthy subjects and from rheumatoid arthritis patients indeed demonstrated that 30% of healthy subject and 36% of rheumatoid arthritis sera recognized the major mimivirus capsid protein L425. Moreover, whereas 6% of healthy subject sera recognized the mimivirus collagen protein L71, 22% of rheumatoid arthritis sera were positive for mimivirus L71. Accordingly, our study shows that environmental exposure to mimivirus represents a risk factor in triggering autoimmunity to collagens

Hybrid Energy Management System Consisting of Battery and Supercapacitor for Electric Vehicle

This paper is mainly focused on Hybrid Energy Management System (HEMS) consisting of Battery (BT) and Super capacitor (SC). Two energy sources connected in with same DC link in parallel manner with the help of Bidirectional DC-DC converter, which is used to separate control of power flow of each source. Here Permanent magnet dc motor (PMDC) motor used as a load and speed control of PMDC motor can be done by PWM method for this purpose chopper circuit is used. Input of chopper circuit is DC link and output of the chopper is given to PMDC motor. This method of energy management gives power splitting between two sources based on State of Charge (SOC) of each individual source during different state of vehicle such as acceleration, constant running and deceleration. Improved filter-based power splitting techniques is implemented. Three acceleration reference points were taken for power splinting at different SOC levels of both energy sources. Objective of this proposed method is best use of both the sources i.e. battery and supercapacitor and maximum use of supercapacitor energy at the time of transient conditions. Battery supply energy during normal running condition or very less load condition. Hence during transient condition SC directly react with system and gives peak power requirement, so stress on battery is reduces hence lifetime of battery is increase, also power available during braking is store in SC and battery, so independence of Electric Vehicle (EV) is increases. Because of less peak power requirement, batteries with less peak output power is used so it is reduced size and cost of batteries. Matlab- Simulink software is used for simulation and also small scale hardware is also implemented of proposed method

Hybrid Energy Management System Consisting of Battery and Supercapacitor for Electric Vehicle

This paper is mainly focused on Hybrid Energy Management System (HEMS) consisting of Battery (BT) and Super capacitor (SC). Two energy sources connected in with same DC link in parallel manner with the help of Bidirectional DC-DC converter, which is used to separate control of power flow of each source. Here Permanent magnet dc motor (PMDC) motor used as a load and speed control of PMDC motor can be done by PWM method for this purpose chopper circuit is used. Input of chopper circuit is DC link and output of the chopper is given to PMDC motor. This method of energy management gives power splitting between two sources based on State of Charge (SOC) of each individual source during different state of vehicle such as acceleration, constant running and deceleration. Improved filter-based power splitting techniques is implemented. Three acceleration reference points were taken for power splinting at different SOC levels of both energy sources. Objective of this proposed method is best use of both the sources i.e. battery and supercapacitor and maximum use of supercapacitor energy at the time of transient conditions. Battery supply energy during normal running condition or very less load condition. Hence during transient condition SC directly react with system and gives peak power requirement, so stress on battery is reduces hence lifetime of battery is increase, also power available during braking is store in SC and battery, so independence of Electric Vehicle (EV) is increases. Because of less peak power requirement, batteries with less peak output power is used so it is reduced size and cost of batteries. Matlab- Simulink software is used for simulation and also small scale hardware is also implemented of proposed method

An Organizational-Level Program of Intervention for AKI: A Pragmatic Stepped Wedge Cluster Randomized Trial

Background Variable standards of care may contribute to poor outcomes associated with AKI. We evaluatedwhether a multifaceted intervention (AKI e-alerts, an AKI care bundle, and an education program)would improve delivery of care and patient outcomes at an organizational level.Methods A multicenter, pragmatic, stepped-wedge cluster randomized trial was performed in five UK hospitals,involving patients with AKI aged$18 years. The intervention was introduced sequentially across fixed three-monthperiods according to a randomly determined schedule until all hospitals were exposed. The primary outcome was30-day mortality,withpre-specifiedsecondaryendpointsandanestedevaluationof careprocessdelivery.Thenatureof the intervention precluded blinding, but data collection and analysiswere independent of project delivery teams.Results We studied 24,059 AKI episodes, finding an overall 30-day mortality of 24.5%, with no differencebetween control and intervention periods. Hospital length of stay was reduced with the intervention(decreases of 0.7, 1.1, and 1.3 days at the 0.5, 0.6, and 0.7 quantiles, respectively). AKI incidence increasedand was mirrored by an increase in the proportion of patients with a coded diagnosis of AKI. Our assessmentof process measures in 1048 patients showed improvements in several metrics including AKI recognition,medication optimization, and fluid assessment.Conclusions A complex, hospital-wide intervention to reduce harm associated with AKI did not reduce30-day AKImortality but did result in reductions in hospital length of stay, accompanied by improvementsin in quality of care. An increase in AKI incidence likely reflected improved recognitio

Deoxyribonucleic acid damage gene expression, ligase activity and correlation with coronary atherosclerotic plaque morphology.

Despite therapeutic and interventional technological advances, the global burden of cardiovascular disease is increasing. Accumulated deoxyribonucleic acid (DNA) damage and subsequent repair pathways are now increasingly recognised as a causal factor in the initiation and progression of atherosclerosis. These molecular alterations have been shown to occur within affected vasculature, plaque microenvironment as well as in circulating cells. The DNA damage response (DDR) pathway is reliant on post-translational modification of sensing proteins which activate a signalling cascade to repair, if possible, DNA damaged sites in response to various environmental and physiological insults. Most studies to-date have focussed on animal models and cells cultured directly from atherosclerotic plaque to ascertain if altered DDR and DNA repair exist and indeed contribute to the atherosclerotic process. By using peripheral whole blood as the base for down-stream analyses, an accessible method of determining if altered expression of genes involved in DDR and enzymes involved in DNA repair could be exploited. DNA ligase is crucial in single (ssDNA) and double-stranded DNA break repair (DSBR) by facilitating the joining of DNA strands by catalysing phosphodiester bond formation. It was therefore chosen as a marker of DNA repair being a key enzyme involved in base excision repair (BER) and DSBR. This study examined the differential expression of 22 genes pertinent in the DNA damage and response pathway (DDR), in addition to DNA ligase activity, between patients with stable, unstable coronary atherosclerosis (both undergoing percutaneous coronary intervention for obstructive coronary disease) and healthy controls. In addition, correlations were performed between atherosclerotic plaque features and both DNA ligase activity and the genes of interest. To accurately analyse plaque morphology, frequency domain optical coherence tomography (FD-OCT) was used which allowed high resolution delineation of fibrous tissue, lipid accumulation, calcific deposition and fibrous cap thickness, all key features in plaque vulnerability and therefore of clinical significance. Peripheral blood mononuclear cells (PBMC) were isolated and DNA repair activity was measured from derived nuclear extracts, using a novel microplate assay examining mean apparent DNA ligase activity. A custom microarray for the 22 genes of interest was used to perform quantitative reverse transcription polymerase chain reaction for differential gene expression between all 3 cohorts of patients recruited. Data from this study demonstrated differences in DNA ligase activity and expression of genes involved in the DDR in patients with coronary atherosclerosis. DNA ligase activity correlated with the arc of lipid and cap thickness in both stable and unstable coronary patients. Differential DDR gene expression also correlated with fibrous cap thickness, predominantly in the unstable coronary group. This suggests that such alterations may contribute to the development and progression of the atherosclerotic lipid rich necrotic core as well as protective fibrous cap thickness. Although significant correlations were found between DNA ligase, genes of interest and plaque features, this study demonstrates an association but does not provide a direct mechanism by which alterations in DDR contribute to atherogenesis. Further studies are required to address differential expression across a broader spectrum of genes involved in DDR in coronary artery disease