Evolutionary trends in Transmit/Receive Module for Active Phased Array Radars

Worldwide, defense technologies are rapidly evolving and are currently aiming at integrating diverse functionalities like Radar, Electronic Warfare, Communications, etc., on a singular miniaturized platform. Hence, it cannot be denied that the advancements in modern Active Phased Array Radar technologies assume a critical role towards the achievement of this goal. A typical Active Phased Array Radar comprises of an Active Antenna Array Unit (AAAU) consisting of a large number of radiating elements, Transmit/Receive (T/R) Modules with other associated RF and digital circuitry and power electronics.  This paper presents mainly the developments in Transmit/Receive (T/R) Module technology, which assimilates various stages of the technological evolution - past, current and futuristic. It discusses how these technologies contribute towards the improvement of efficiency, miniaturization and reliability without compromising its performance parameters

Natural mutations of human XDH promote the nitrite (NO2 −)-reductase capacity of xanthine oxidoreductase: A novel mechanism to promote redox health?

Several rare genetic variations of human XDH have been shown to alter xanthine oxidoreductase (XOR) activity leading to impaired purine catabolism. However, XOR is a multi-functional enzyme that depending upon the environmental conditions also expresses oxidase activity leading to both O2·- and H2O2 and nitrite (NO2−) reductase activity leading to nitric oxide (·NO). Since these products express important, and often diametrically opposite, biological activity, consideration of the impact of XOR mutations in the context of each aspect of the biochemical activity of the enzyme is needed to determine the potential full impact of these variants. Herein, we show that known naturally occurring hXDH mutations do not have a uniform impact upon the biochemical activity of the enzyme in terms of uric acid (UA), reactive oxygen species (ROS) and nitric oxide ·NO formation. We show that the His1221Arg mutant, in the presence of xanthine, increases UA, O2·- and NO generation compared to the WT, whilst the Ile703Val increases UA and ·NO formation, but not O2·-. We speculate that this change in the balance of activity of the enzyme is likely to endow those carrying these mutations with a harmful or protective influence over health that may explain the current equipoise underlying the perceived importance of XDH mutations. We also show that, in presence of inorganic NO2−, XOR-driven O2·- production is substantially reduced. We suggest that targeting enzyme activity to enhance the NO2−-reductase profile in those carrying such mutations may provide novel therapeutic options, particularly in cardiovascular disease

Randomised, double-blind, placebo-controlled clinical trial investigating the effects of inorganic nitrate in hypertension-induced target organ damage: protocol of the NITRATE-TOD study in the UK

© 2020 Author(s). Introduction: Arterial stiffness and left ventricular (LV) hypertrophy are the key markers of hypertensive target organ damage (TOD) associated with increased cardiovascular morbidity and mortality. We have previously shown that dietary inorganic nitrate supplementation lowers blood pressure (BP) in hypertension, however, whether this approach might also improve markers of hypertensive TOD is unknown. In this study, we will investigate whether daily dietary inorganic nitrate administration reduces LV mass and improves measures of arterial stiffness. Methods and design: NITRATE-TOD is a double-blind, randomised, single-centre, placebo-controlled phase II trial aiming to enrol 160 patients with suboptimal BP control on one or more antihypertensives. Patients will be randomised to receive 4 months once daily dose of either nitrate-rich beetroot juice or nitrate-deplete beetroot juice (placebo). The primary outcomes are reduction in LV mass and reduction in pulse wave velocity (PWV) and central BP. The study has a power of 95% for detecting a 9 g LV mass change by cardiovascular MRI (∼6% change for a mildly hypertrophied heart of 150 g). For PWV, we have a power of >95% for detecting a 0.6 m/s absolute change. For central systolic BP, we have a>90% power to detect a 5.8 mm Hg difference in central systolic BP. Secondary end points include change in ultrasound flow-mediated dilation, change in plasma nitrate and nitrite concentration and change in BP. Ethics and dissemination: The study was approved by the London - City and East Research Ethics Committee (10/H0703/98). Trial results will be published according to the Consolidated Standards of Reporting Trials statement and will be presented at conferences and reported in peer-reviewed journals

An Observational Study Assessing Immediate Complete Versus Delayed Complete Revascularisation in Patients with Multi-Vessel Disease Undergoing Primary Percutaneous Coronary Intervention.

Background: More than half of the patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) have multi-vessel coronary artery disease. This is associated with worse outcomes compared with single vessel disease. Whilst evidence now exists to support complete revascularisation for bystander disease the optimal timing is still debated. This study aimed to compare clinical outcomes in patients with STEMI and multi-vessel disease who underwent complete revascularisation as inpatients in comparison to patients who had staged PCI as early outpatients. Methods and results: We conducted an observational cohort study consisting of 1522 patients who underwent primary PCI with multi-vessel disease from 2012 to 2019. Exclusions included patients with cardiogenic shock and previous CABG. Patients were split into 2 groups depending on whether they had complete revascularisation performed as inpatients or as staged PCI at later outpatient dates. The primary outcome of this study was major adverse cardiac events (consisting of myocardial infarction, target vessel revascularisation and all-cause mortality).834 (54.8%) patients underwent complete inpatient revascularisation and 688 patients (45.2%) had outpatient PCI (median 43 days post discharge). Of the inpatient group, 652 patients (78.2%) underwent complete revascularisation during the index procedure whilst 182 (21.8%) patients underwent inpatient bystander PCI in a second procedure. Overall, there were no significant differences between the groups with regards to their baseline or procedural characteristics. Over the follow-up period there was no significant difference in MACE between the cohorts (P = .62), which persisted after multivariate adjustment (HR 1.21 [95% CI 0.72-1.96]). Furthermore, in propensity-matched analysis there was no significant difference in outcome between the groups (HR: 0.86 95% CI: 0.75-1.25). Conclusions: Our study demonstrated that the timing of bystander PCI after STEMI did not appear to have an effect on cardiovascular outcomes. We suggest that patients with multi-vessel disease can potentially be discharged promptly and undergo early outpatient bystander PCI. This could significantly reduce length of stay in hospital

The Use of Novel Oral Anti-Coagulant's (NOAC) compared to Vitamin K Antagonists (Warfarin) in patients with Left Ventricular thrombus after Acute Myocardial Infarction (AMI).

This is a pre-copyedited, author-produced version of an article accepted for publication in European Heart Journal - Cardiovascular Pharmacotherapy following peer review. The version of record: Daniel A Jones, Paul Wright, Momin A Alizadeh, Sadeer Fhadil, Krishnaraj S Rathod, Oliver Guttmann, Charles Knight, Adam Timmis, Andreas Baumbach, Andrew Wragg, Anthony Mathur, Sotiris Antoniou, The Use of Novel Oral Anti-Coagulant’s (NOAC) compared to Vitamin K Antagonists (Warfarin) in patients with Left Ventricular thrombus after Acute Myocardial Infarction (AMI), European Heart Journal - Cardiovascular Pharmacotherapy, pvaa096, https://doi.org/10.1093/ehjcvp/pvaa096AIM: Current guidelines recommend the use of Vitamin K Antagonist (VKA) for up to 3 - 6 months for treatment of LV thrombus post-acute myocardial infarction (AMI). However, based on evidence supporting non-inferiority of Novel Oral Anti-Coagulant's (NOAC) compared to VKA for other indications such as DVT, PE and thrombo-embolic prevention in atrial fibrillation, NOACs are being increasingly used off licence for the treatment of LV thrombus post AMI. In this study we investigated the safety and effect of NOACs compared to VKA on LV thrombus resolution in patients presenting with AMI. METHODS AND RESULTS: This was an observational study of 2,328 consecutive patients undergoing Coronary Angiography +/- Percutaneous Coronary Intervention (PCI) for AMI between May 2015- December 2018, at a UK cardiac centre. Patients' details were collected from the hospital electronic database. The primary end-point was rate of LV thrombus resolution with bleeding rates a secondary outcome.Left ventricular (LV) thrombus was diagnosed in 101 (4.3%) patients. Sixty patients (59.4%) were started on VKA and 41 patients (40.6%) on NOAC therapy (rivaroxaban: 58.5%, apixaban, 36.5% and edoxaban: 5.0%). Both groups were well matched in terms of baseline characteristics including age, previous cardiac history (Previous MI, PCI, CABG), and cardiovascular risk factors (Hypertension, Diabetes, Hypercholesterolaemia).Over the follow up period (median 2.2 years), overall rates of LV thrombus resolution were 86.1%. There was greater and earlier LV thrombus resolution in the NOAC group compared to patients treated with warfarin (82% vs 64.4%, p = 0.0018, at 1 year), which persisted after adjusting for baseline variables (OR 1.8 95% CI 1.2-2.9). Major bleeding events during the f/u period were lower in the NOAC group, compared with VKA group (0% vs 6.7%, p = 0.030) with no difference in rates of systemic thromboembolism (5% vs 2.4%, p = 0.388). CONCLUSION: This data suggests improved thrombus resolution in post ACS LV thrombosis in patients treated with NOACs compared to vitamin K antagonists. This improvement in thrombus resolution was accompanied with a better safety profile for NOAC patients' vs VKA treated patients. Thus, provides data to support a randomised trial to answer this question

The clinical and cost effectiveness of steroid injection compared with night splints for carpal tunnel syndrome: the INSTINCTS randomised clinical trial study protocol.

BACKGROUND: Patients diagnosed with idiopathic mild to moderate carpal tunnel syndrome (CTS) are usually managed in primary care and commonly treated with night splints and/or corticosteroid injection. The comparative effectiveness of these interventions has not been reliably established nor investigated in the medium and long term. The primary objective of this trial is to investigate whether corticosteroid injection is effective in reducing symptoms and improving hand function in mild to moderate CTS over 6 weeks when compared with night splints. Secondary objectives are to determine specified comparative clinical outcomes and cost effectiveness of corticosteroid injection over 6 and 24 months. METHOD/DESIGN: A multicentre, randomised, parallel group, clinical pragmatic trial will recruit 240 adults aged ≥18 years with mild to moderate CTS from GP Practices and Primary-Secondary Care Musculoskeletal Interface Clinics. Diagnosis will be by standardised clinical assessment. Participants will be randomised on an equal basis to receive either one injection of 20 mg Depo-Medrone or a night splint to be worn for 6 weeks. The primary outcome is the overall score of the Boston Carpal Tunnel Questionnaire (BCTQ) at 6 weeks. Secondary outcomes are the BCTQ symptom severity and function status subscales, symptom intensity, interrupted sleep, adherence to splinting, perceived benefit and satisfaction with treatment, work absence and reduction in work performance, EQ-5D-5L, referral to surgery and health utilisation costs. Participants will be assessed at baseline and followed up at 6 weeks, 6, 12 and 24 months. The primary analysis will use an intention to treat (ITT) approach and multiple imputation for missing data. The sample size was calculated to detect a 15 % greater improvement in the BTCQ overall score in the injection group compared to night-splinting at approximately 90 % power, 5 % two-tailed significance and allows for 15 % loss to follow-up. DISCUSSION: The trial makes an important contribution to the evidence base available to support effective conservative management of CTS in primary care. No previous trials have directly compared these treatments for CTS in primary care populations, reported on clinical effectiveness at more than 6 months nor compared cost effectiveness of the interventions. TRIAL REGISTRATION: Trial registration: EudraCT 2013-001435-48 (registered 05/06/2013), ClinicalTrials.gov NCT02038452 (registered 16/1/2014), and Current Controlled Trials ISRCTN09392969 (retrospectively registered 01/05/2014)

The clinical and cost-effectiveness of corticosteroid injection versus night splints for carpal tunnel syndrome (INSTINCTS trial): an open-label, parallel group, randomised controlled trial

Background To our knowledge, the comparative effectiveness of commonly used conservative treatments for carpal tunnel syndrome has not been evaluated previously in primary care. We aimed to compare the clinical and cost-effectiveness of night splints with a corticosteroid injection with regards to reducing symptoms and improving hand function in patients with mild or moderate carpal tunnel syndrome. Methods We did this randomised, open-label, pragmatic trial in adults (≥18 years) with mild or moderate carpal tunnel syndrome recruited from 25 primary and community musculoskeletal clinics and services. Patients with a new episode of idiopathic mild or moderate carpal tunnel syndrome of at least 6 weeks' duration were eligible. We randomly assigned (1:1) patients (permutated blocks of two and four by site) with an online web or third party telephone service to receive either a single injection of 20 mg methylprednisolone acetate (from 40 mg/mL) or a night-resting splint to be worn for 6 weeks. Patients and clinicians could not be masked to the intervention. The primary outcome was the overall score of the Boston Carpal Tunnel Questionnaire (BCTQ) at 6 weeks. We used intention-to-treat analysis, with multiple imputation for missing data, which was concealed to treatment group allocation. The trial is registered with the European Clinical Trials Database, number 2013-001435-48, and ClinicalTrial.gov, number NCT02038452. Findings Between April 17, 2014, and Dec 31, 2016, 234 participants were randomly assigned (118 to the night splint group and 116 to the corticosteroid injection group), of whom 212 (91%) completed the BCTQ at 6 weeks. The BCTQ score was significantly better at 6 weeks in the corticosteroid injection group (mean 2·02 [SD 0·81]) than the night splint group (2·29 [0·75]; adjusted mean difference −0·32; 95% CI −0·48 to −0·16; p=0·0001). No adverse events were reported. Interpretation A single corticosteroid injection shows superior clinical effectiveness at 6 weeks compared with night-resting splints, making it the treatment of choice for rapid symptom response in mild or moderate carpal tunnel syndrome presenting in primary care

Randomised, double-blind, placebo-controlled study investigating the effects of inorganic nitrate on vascular function, platelet reactivity and restenosis in stable angina: protocol of the NITRATE-OCT study

KSR and this work are funded by an NIHR Doctoral Fellowship (DRF-2014-07-008

COVID-19 and changes in activity and treatment of ST elevation MI from a UK cardiac centre.

Background: The international healthcare response to COVID-19 has been driven by epidemiological data related to case numbers and case fatality rate. Second order effects have been less well studied. This study aimed to characterise the changes in emergency activity of a high-volume cardiac catheterisation centre and to cautiously model any excess indirect morbidity and mortality. Method: Retrospective cohort study of patients admitted with acute coronary syndrome fulfilling criteria for the heart attack centre (HAC) pathway at St. Bartholomew's hospital, UK. Electronic data were collected for the study period March 16th - May 16th 2020 inclusive and stored on a dedicated research server. Standard governance procedures were observed in line with the British Cardiovascular Intervention Society audit. Results: There was a 28% fall in the number of primary percutaneous coronary interventions (PCIs) for ST elevation myocardial infarction (STEMI) during the study period (111 vs. 154) and 36% fewer activations of the HAC pathway (312 vs. 485), compared to the same time period averaged across three preceding years. In the context of 'missing STEMIs', the excess harm attributable to COVID-19 could result in an absolute increase of 1.3% in mortality, 1.9% in nonfatal MI and 4.5% in recurrent ischemia. Conclusions: The emergency activity of a high-volume PCI centre was significantly reduced for STEMI during the peak of the first wave of COVID-19. Our data can be used as an exemplar to help future modelling within cardiovascular workstreams to refine aggregate estimates of the impact of COVID-19 and inform targeted policy action