Publications by authors named "Thomas J Ryan"

There is a high unmet need for early detection approaches for diffuse gastric cancer (DGC). We examined whether the stool proteome of mouse models of gastric cancer (GC) and individuals with hereditary diffuse gastric cancer (HDGC) have utility as biomarkers for early detection. Proteomic mass spectrometry of the stool of a genetically engineered mouse model driven by oncogenic KrasG12D and loss of p53 and Cdh1 in gastric parietal cells [known as Triple Conditional (TCON) mice] identified differentially abundant proteins compared with littermate controls.

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Background: Jones fractures remain a challenging treatment entity in orthopaedics. Biomechanical stresses, including increased fifth metatarsal (5MT) lateral angle deviation (MLAD), are associated with increased fracture and refracture rates. Current fixation techniques produce good outcomes; however, they do not address metatarsal morphology, which can predispose to refracture.

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Objectives: The goal of this analysis was to examine the comparative effectiveness of coronary artery bypass grafting versus percutaneous coronary intervention among patients aged less than 60 years.

Methods: We performed a multicenter, retrospective analysis of all cardiac revascularization procedures from 2005 to 2015 among 7 medical centers. Inclusion criteria were age less than 60 years and 70% stenosis or greater in 1 or more major coronary artery distribution.

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Background: Paraplegia remains a significant complication of thoracoabdominal aortic intervention. We previously reported that diazoxide (DZ), enhances the neuroprotective efficacy of erythropoietin (EPO). We hypothesized that DZ and EPO combined treatment attenuates spinal cord ischemic injury through upregulation of nerve growth factor (NGF).

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Background: Delayed paraplegia remains a feared complication of thoracoabdominal aortic intervention. Pharmacologic preconditioning with diazoxide (DZ), an adenosine 5'-triphosphate-sensitive potassium channel opener, results in neuroprotection against ischemic insult. However, the effects of DZ in spinal cord ischemia-reperfusion injury have not been fully elucidated.

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Background: Paraplegia remains a devastating complication of thoracoabdominal aortic intervention. Metabolic stress induces expression of beta common receptor subunit of erythropoietin (EPO) receptor (βcR) to exert a neuroprotective effect in spinal cord ischemia reperfusion injury (SCIR). Diazoxide (DZ) has been shown to induce ischemic tolerance.

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The infiltration of local anesthetic has been shown to reduce postoperative pain in knee arthroscopy. Several studies have shown that the addition of agents such as magnesium and nonsteroidal antiinflammatory drugs (NSAIDs) result in an increased time to first analgesia and overall reduction in pain. The aim of this systematic review and meta-analysis was to determine whether the addition of an α-2 agonist (A2A) to intra-articular local anesthetic, results in a reduction in postoperative pain.

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Background: Paraplegia remains the most feared complication of complex thoracoabdominal aortic intervention. Although erythropoietin (EPO) has demonstrated neuroprotective effects in spinal cord ischemia, it does not work until expression of the beta common receptor subunit of the EPO receptor (βcR) is induced by ischemia. We hypothesized that the βcR can be induced by diazoxide (DZ), amplifying the neuroprotective effects of EPO in spinal cord ischemia-reperfusion injury.

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Mitral regurgitation (MR) is a complex valve lesion that can pose significant management challenges for the cardiovascular clinician. This Expert Consensus Document emphasizes that recognition of MR should prompt an assessment of its etiology, mechanism, and severity, as well as indications for treatment. A structured approach to evaluation based on clinical findings, precise echocardiographic imaging, and when necessary, adjunctive testing, can help clarify decision making.

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We have developed an engineered heart tissue (EHT) system that uses laser-cut sheets of decellularized myocardium as scaffolds. This material enables formation of thin muscle strips whose biomechanical characteristics are easily measured and manipulated. To create EHTs, sections of porcine myocardium were laser-cut into ribbon-like shapes, decellularized, and mounted in specialized clips for seeding and culture.

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Value-Based Healthcare: Summit 2014 clearly achieved the three goals set forth at the beginning of this document. First, the live event informed and educated attendees through a discussion of the evolving value-based healthcare environment, including a collaborative effort to define the important role of cardiovascular ultrasound in that environment. Second, publication of these Summit proceedings in the Journal of the American Society of Echocardiography will inform a wider audience of the important insights gathered.

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Background: Several randomized trials comparing bare-metal stents to Drug-Eluting Stents (DES) have demonstrated a significant reduction in Target Vessel Revascularization (TVR) and Target Lesion Revascularization (TLR) exists with the use of drug-eluting stents, without compromising survival. These conclusions are based on restricted inclusion criteria for patients and lesion. It is unknown if these results can be generalized to an unselected patient population and more complex disease.

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Background: The COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) trial was designed to compare optimal medical therapy alone versus optimal medical therapy and percutaneous coronary intervention (PCI) for treatment of patients with stable coronary artery disease and showed equal efficacy for optimal medical therapy with or without PCI. The impact of results from the COURAGE trial on clinical practice is unknown.

Methods And Results: We analyzed 26 388 consecutive patients from the Northern New England Cardiovascular Disease PCI Registry who underwent PCI between January 2006 and June 2009.

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Background: Many reported studies of medical trainees and physicians have demonstrated major deficiencies in correctly identifying heart sounds and murmurs, but cardiologists had not been tested. We previously confirmed these deficiencies using a 50-question multimedia cardiac examination (CE) test featuring video vignettes of patients with auscultatory and visible manifestations of cardiovascular pathology (virtual cardiac patients). Previous testing of 62 internal medical faculty yielded scores no better than those of medical students and residents.

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Objectives: The aim of this study was to determine correlates of acute/subacute coronary stent thrombosis among unselected patients treated in the era of routine dual antiplatelet therapy and specifically to investigate the influence of prophylactic administration of glycoprotein IIb/IIIa (GpIIb-IIIa) inhibitors and use of clopidogrel versus ticlopidine on the development of coronary stent thrombosis (ST).

Background: Because of a relative infrequency of ST events and relatively uniform practice patterns within randomized trials, previous studies have had a limited ability to address whether the use of different antiplatelet regimens at the time of coronary stenting is associated with differences in ST.

Methods: We performed a multicenter, case-control study to evaluate clinical, angiographic, and pharmacologic/procedural correlates of ST.

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With the many advances in rapid reperfusion therapy for management of acute ST segment elevation myocardial infarction (STEMI), there is a need to revisit the current plan for prehospital triage (point of entry). Until recently in Boston, and nationwide, there has been a policy that patients with suspected acute MI were brought to the nearest hospital. Then, if ST segment elevation was present, patients were treated with either thrombolytic therapy or primary percutaneous coronary intervention (PCI).

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Background: A prediction rule for determining the post-percutaneous coronary intervention (PCI) risk of developing contrast-induced nephropathy (> or = 25% or > or = 0.5 mg/dL increase in creatinine) has been reported. However, little work has been done on predicting pre-PCI patient-specific risk for developing more serious renal dysfunction (SRD; new dialysis, > or = 2.

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Gamma-glutamyl hydrolase, a cysteine peptidase, catalyzes the hydrolysis of poly-gamma-glutamate derivatives of folate cofactors and many antifolate drugs. We have used internally quenched fluorogenic derivatives of glutamyl-gamma-glutamate and (4,4-difluoro)glutamyl-gamma-glutamate to examine the effect of fluorine substitution adjacent to the scissile isopeptide bond. Using a newly developed continuous fluorescence assay, the hydrolysis of both substrates could be described by Michaelis-Menten kinetics.

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Background: There is limited information comparing long-term survival after percutaneous coronary intervention (PCI) versus coronary artery bypass grafting (CABG) in patients aged 80 years and older. We studied the long-term survival of octogenarians with multivessel coronary artery disease undergoing PCI or CABG who might have been candidates for either procedure.

Methods: We identified 1693 patients, aged 80 to 89, with two-vessel disease (57.

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Human gamma-glutamyl hydrolase (hGH) is a key enzyme in the metabolism of folic acid and in the pharmacology of many antifolate drugs. hGH catalyzes removal of the poly-gamma-glutamate chains of intracellular folic acid and antifolates. hGH crystallized as a homodimer with two putative active sites.

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