Publications by authors named "Waller H"

The α-amino-radical constitutes a versatile reactive intermediate that has been used to great effect in the synthesis of complex amine-containing products. Here, we report the development of a multicomponent photocatalytic platform enabling access to all-alkyl α-amino-radicals, exploiting the oxidative formation of silyl-radicals from commercially available tris(trimethylsilyl)silane. A key design element of the new process involves the role of silyl-radicals in generating α-amino-radicals from iminium ions as part of an oxidatively initiated photocatalytic radical chain process.

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The use of lead shotgun ammunition for hunting has been banned in a few jurisdictions and habitats, principally to protect wild birds from poisoning by ingestion of spent lead shot. The EU and UK REACH processes have recently considered bans on lead ammunition throughout the European Union and United Kingdom, including assessments of possible health benefits from reduced human dietary exposure to lead from game meat. Comparisons of the mean lead concentrations in meat from gamebirds killed using lead and non‑lead shotgun ammunition have not been published.

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Sexual signalling traits and their associated genetic components play a crucial role in the speciation process, as divergence in these traits can contribute to sexual isolation. Despite their importance, our understanding of the genetic basis of variable sexual signalling traits linked to speciation remains limited. In this study, we present new genetic evidence of Quantitative Trait Loci (QTL) underlying divergent sexual signalling behaviour, specifically pulse rate, in the Hawaiian cricket Laupala.

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Therapies like cognitive behavioral therapy and interpersonal psychotherapy are regarded as highly effective treatments for perinatal mood and anxiety disorders. Therapists appreciate robust research supporting the efficacy of these evidenced-based treatments and the structure of the tools these therapies provide for effective intervention. Less has been written on supportive psychotherapeutic techniques and few of those writings provide instruction or tools for therapists who wish to strengthen their skills in this therapeutic approach.

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Introduction: After more than two years the Coronavirus disease-19 (COVID-19) pandemic continues to burden healthcare systems and economies worldwide, and it is evident that the effects on the immune system can persist for months post-infection. The activity of myeloid cells such as monocytes and dendritic cells (DC) is essential for correct mobilization of the innate and adaptive responses to a pathogen. Impaired levels and responses of monocytes and DC to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is likely to be a driving force behind the immune dysregulation that characterizes severe COVID-19.

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In tissue engineering, the composition and the structural arrangement of molecular components within the extracellular matrix (ECM) determine the physical and biochemical features of a scaffold, which consequently modulate cell behavior and function. The microenvironment of the ECM plays a fundamental role in regulating angiogenesis. Numerous strategies in tissue engineering have attempted to control the spatial cues mimicking in vivo angiogenesis by using simplified systems.

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Objectives: The natural history and optimal management of spontaneous renal artery dissections (SRADs) are poorly understood. We compared baseline characteristics, presentation, management, and outcomes between patients with symptomatic versus asymptomatic SRADs.

Methods: We performed a retrospective review of medical charts for patients diagnosed with SRAD at a single, tertiary care center.

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Background: Clinical outcomes in women with peripheral artery disease (PAD) after revascularization procedures are worse compared to men, yet there is little in the existing literature as why this may be the case. Platelet Mapping is an emerging point-of-care viscoelastic technology that measures the comprehensive properties of a blood clot, including fibrin-platelet interactions. This prospective observational study aimed to characterize the clinical and Platelet Mapping profiles of female and male patients undergoing lower extremity revascularization, and to correlate Platelet Mapping distribution to thrombotic potential.

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There is a growing realization that 3D cell culture better mimics complex in vivo environments than 2D, lessening aberrant cellular behaviors and ultimately improving the outcomes of experiments. Chemically crosslinked hydrogels which imitate natural extracellular matrix (ECM) are proven cell culture platforms, but the encapsulation of cells within these hydrogel networks requires bioorthogonal crosslinking chemistries which can be cytotoxic, synthetically demanding, and costly. Capsular antigen fragment 1 (Caf1) is a bacterial, polymeric, fimbrial protein which can be genetically engineered to imitate ECM.

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COVID-19 generates SARS-CoV-2-specific antibodies in immunocompetent individuals. However, in immunocompromised patients, the humoral immunity following infection may be impaired or absent. Recently, the assessment of cellular immunity to SARS-CoV-2, both following natural infection and vaccination, has contributed new knowledge regarding patients with low or no antibody responses.

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Aim: To assess the impact of the sodium-glucose co-transporter-2 (SGLT2) inhibitor empagliflozin (25 mg once-daily), dietary energy restriction, or both combined, on circulating appetite-regulatory peptides in people with type 2 diabetes (T2D) and overweight or obesity.

Materials And Methods: In a double-blind, placebo-controlled trial, 68 adults (aged 30-75 years) with T2D (drug naïve or on metformin monotherapy; HbA1c 6.0%-10.

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The pathogenic bacterium Yersina pestis is protected from macrophage engulfment by a capsule like antigen, F1, formed of long polymers of the monomer protein, Caf1. However, despite the importance of this pathogen, the mechanism of protection was not understood. Here we demonstrate how F1 protects the bacteria from phagocytosis.

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Background: Postoperative infection and wound dehiscence rates are higher than expected in peripheral artery disease and contribute significantly to limb loss and mortality. Microvascular pathology characterized by microthrombi and increased platelet aggregation have been cited as contributing factors to poor wound healing and infection. The emergence of viscoelastic assays, such as thromboelastography with platelet mapping (TEG-PM), have been utilized to identify prothrombotic states and may provide insight into a patient's microvascular coagulation profile.

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Background: Pregnancy is a known risk factor for developing varicose veins (VV). However, pregnancy is often considered a homogeneous entity and few studies have examined if specific characteristics and complications of pregnancy may influence VV formation. This study sought to identify which pregnancy-specific factors are associated with the development of VV.

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Background: There is a paucity of data regarding the conversion rate from dry gangrene to wet gangrene after lower extremity revascularization. This study aimed to determine the rate of conversion from dry to wet gangrene within 30 days post-procedure in patients who underwent endovascular or open revascularization for critical limb ischemia. Secondary aims included determining the time to conversion and associated risk factors with conversion.

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Objective: To determine if routine completion angiography for lower extremity bypasses using vein conduit results in lower rates of postoperative bypass occlusion.

Summary Of Background Data: With the increasing availability of on-table angiography and significant advancements in endovascular techniques, some operators routinely perform completion angiograms. The effect of this surgical paradigm has yet to be rigorously compared to the more widespread selective use of completion imaging in the modern era.

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Objective: Spinal cord ischemia (SCI) is one of the most devastating complications after descending thoracic aortic (DTA) and thoracoabdominal aortic (TAA) repairs. Patients who develop SCI have a poor prognosis, with mortality rates reaching 75% within the first year after surgery. Many factors have been shown to increase the risk of this complication, including the extent of TAA repair, length of aortic and collateral network coverage, embolization, and reduced spinal cord perfusion pressure.

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Objective: Penetrating atherosclerotic ulcers (PAUs) in aortic branch vessels are rare. There is a paucity of data regarding their long-term natural history and associated management. This study aimed to determine the prevalence and natural history of aortic branch PAUs.

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Climate change will necessitate evermore frequent and complex managed retreats in the future, and drafting policies that are equitable and just for those residents who are relocating will be essential. The USA's first federally funded, community-scale, climate-driven resettlement is currently underway in coastal Louisiana. In January 2016, the U.

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Capsular antigen fragment 1 (Caf1) is an oligomeric protein consisting of 15 kDa monomeric subunits that are non-covalently linked through exceptionally strong and kinetically inert interactions into a linear polymer chain. It has been shown that after its thermal depolymerisation into unfolded monomeric subunits, Caf1 is able to efficiently repolymerise in vitro to reform its polymeric structure. However, little is known about the nature of the repolymerisation process.

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Demand continues to grow for biomimetic materials able to create well-defined environments for modulating the behaviour of living cells in culture. Here, we describe hydrogels based upon the polymeric bacterial fimbriae protein capsular antigen fragment 1 (Caf1) that presents tunable biological properties for enhanced tissue cell culture applications. We demonstrate how Caf1 hydrogels can regulate cellular functions such as spreading, proliferation and matrix deposition of human dermal fibroblast cells (hDFBs).

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The mechanisms behind the beneficial cardiovascular effects of glucagon-like peptide-1 receptor agonists (GLP-1RAs) compared with dipeptidyl peptidase-4 inhibitors (DPP4is) remain largely unknown, despite both targeting the incretin pathway to improve glycaemic control. In these prespecified secondary analyses of the LYDIA trial, we examined the impact of the GLP-1RA liraglutide (1.8 mg once-daily) and the DPP4i sitagliptin (100 mg once-daily) on circulating cardiovascular biomarkers associated with atherosclerotic risk, including circulating progenitor cells (CPCs).

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Objective: The current Society for Vascular Surgery practice guidelines recommend carotid revascularization for asymptomatic disease in patients with at least a 3-year life expectancy and stenosis >60% when the expected perioperative stroke and death rate is <3%. Based on this recommendation, it was previously determined that asymptomatic patients who require dialysis would not meet the perioperative stroke and death thresholds nor the long-term survival benchmarks to justify carotid surgery. To determine whether carotid surgery for patients requiring dialysis is appropriate, the present study compared the perioperative outcomes after carotid revascularization for dialysis-dependent patients relative to nondialysis patients in a contemporary, national cohort.

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Objective: To examine whether circulating metabolic responses to low-volume high-intensity interval exercise (LV-HIIE) or continuous moderate-intensity aerobic exercise (CME) differ between white Europeans and South Asians with nondiabetic hyperglycemia (NDH).

Research Design And Methods: Thirteen white Europeans and 10 South Asians (combined median [interquartile range] age 67 [60-68] years, HbA 5.9% [5.

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