Publications by authors named "Ridley L"

Background: Severe malaria is associated with impaired nitric oxide (NO) synthase (NOS)-dependent vasodilation, and reversal of this deficit improves survival in murine models. Malaria might have selected for genetic polymorphisms that increase endothelial NO signaling and now contribute to heterogeneity in vascular function among humans. One protein potentially selected for is alpha globin, which, in mouse models, interacts with endothelial NOS (eNOS) to negatively regulate NO signaling.

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Introduction: Urolithiasis is frequently followed up with a low-dose computed tomography of the kidneys ureters and bladder (LD-CTKUB) with doses typically less than 3 millisieverts. Although X-ray is a lower dose (0.5-1.

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Increasing evidence suggests that there is a pivotal role for physical force (mechanotransduction) in the initiation and/or the perpetuation of spondyloarthritis; the review contained herein examines that evidence. Furthermore, we know that damage and inflammation can limit spinal mobility, but is there a cycle created by altered spinal mobility leading to additional damage and inflammation?Over the past several years, mechanotransduction, the mechanism by which mechanical perturbation influences gene expression and cellular behaviour, has recently gained popularity because of emerging data from both animal models and human studies of the pathogenesis of ankylosing spondylitis (AS). In this review, we provide evidence towards an appreciation of the unsolved paradigm of how biomechanical forces may play a role in the initiation and propagation of AS.

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Introduction: Previous studies have demonstrated positive correlations between computed tomography (CT) attenuation of lumbar spine vertebrae and their bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DEXA). However, these studies were performed using a standard 120 kilovoltage peak (kVp) setting. As radiation attenuation in mineralised tissues varies by the tube voltage applied, we determined the diagnostic accuracy of CT attenuation at identifying individuals with low BMD at different kVp settings.

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We present a case of a bronchial artery to pulmonary artery fistula. This occurred in a 77-year-old male of Bangladeshi ethnicity with a new diagnosis of cavitating pulmonary tuberculosis. A 4D CTA protocol was required to elicit the nature of the vascular abnormality.

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Objective: Sacroiliac (SI) joint and spinal inflammation are characteristic of ankylosing spondylitis (AS), but some patients with AS have been identified who have discordant radiographic disease. We studied an AS subgroup with long-standing disease and fused SI joints. We identified factors associated with discrepant degrees of radiographic damage between the SI joints and spine.

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Introduction: Sigmoid volvulus is a potentially devastating and life-threatening condition associated with sigmoid colon redundancy. Many of the classical radiological signs are considered to represent the two adjacent loops of bowel in a mesentero-axial volvulus. However, limited case reports and series have reported on an organo-axial subtype of sigmoid volvulus.

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Background: IgG4-related disease (IgG4-RD) is an autoimmune condition affecting almost every organ system, with an early inflammatory phase and later fibrotic consequences. Vascular manifestations, particularly, large-vessel involvement in IgG4-RD, are well described. However, important IgG4-related effects on medium-sized arteries and the pericardium are less well recognized.

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Background: Coronary artery calcium (CAC) identified on non-gated CT scan of the chest is predictive of major adverse cardiac events (MACE) in multiple studies with guidelines therefore recommending the routine reporting of incidental CAC. These studies have been limited however to the outpatient setting. We aimed to determine the prognostic utility of incidentally identified CAC on CT scan of the chest among hospital inpatients.

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Unlabelled: We assessed two electronic search tools that screen medical records for documented fractures. Both programs reliably identified patients with any fracture but missed individuals with minimal trauma fracture to different degrees. A hybrid tool combining the methodology of both tools is likely to improve the identification of those with osteoporosis.

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A 57-year-old man had presented with a 6-month history of worsening dyspnea, renal failure, hypertension, pancytopenia, and a continuous machinery murmur. Imaging studies revealed pleuropericardial effusions that recurred despite aspiration and suprarenal mid-thoracic aortic occlusion (AO) with extensive collateral vessels to the chest wall, rectus sheath, and diaphragm. A right axillofemoral bypass transformed his clinical course.

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Global peatlands store more carbon than is naturally present in the atmosphere. However, many peatlands are under pressure from drainage-based agriculture, plantation development and fire, with the equivalent of around 3 per cent of all anthropogenic greenhouse gases emitted from drained peatland. Efforts to curb such emissions are intensifying through the conservation of undrained peatlands and re-wetting of drained systems.

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Radiographic axial spondyloarthritis (also known as ankylosing spondylitis [AS]) is a chronic immune-mediated arthritis characterized by inflammation of the axial skeleton, peripheral joints, and entheses. It is estimated that 1 in every 200 people are affected by AS, making it an important healthcare and socioeconomic issue. In this review, we aim to explore the current understanding of AS risk factors and provide a comprehensive update.

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Background: The appendix has a unique place in surgical history. Although the first ever appendicectomy involved a fistula to the skin, fistulae involving the appendix remain uncommon and can lead to unique surgical considerations.

Methods: A systematic review of the literature was performed for case reports of appendiceal fistulae.

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Objective: Multiple cohort studies have compared surgical resection with CT-guided percutaneous ablation for patients with stage 1 non-small cell lung cancer (NSCLC); however, the results have been heterogeneous. This systematic review and meta-analysis aims to compare surgery with ablation for stage 1 NSCLC.

Method: A search of five databases was performed from inception to 5 July 2020.

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Background: Knee pain is a common symptom in the community. There is a wide range of conditions that can cause pain. Identifying the type and severity of the condition is important for effective management.

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Context: Androgen abuse impairs male reproductive and cardiac function, but the rate, extent, and determinants of recovery are not understood.

Objective: To investigate recovery of male reproductive and cardiac function after ceasing androgen intake in current and past androgen abusers compared with healthy non-users.

Methods: Cross-sectional, observational study recruited via social media 41 current and 31 past users (≥3 months since last use, median 300 days since last use) with 21 healthy, eugonadal non-users.

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Objective: This systematic review and meta-analysis investigated risk factors for pneumothorax following CT-guided percutaneous transthoracic lung biopsy.

Methods: A systematic search of nine literature databases between inception to September 2019 for eligible studies was performed.

Results: 36 articles were included with 23,104 patients.

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