Publications by authors named "Roy Smith"

Importance: Venous thromboembolism (VTE) is a severe complication after microsurgical free tissue transfer (FTT) to the head and neck. Hypothermia during surgery is a modifiable risk factor, and avoiding it may reduce the postoperative VTE rate.

Objective: To assess the association between hypothermia (temperature <36 °C) and postoperative VTE and free flap pedicle thrombosis rates after head and neck reconstruction with FTT.

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Recent advances in therapy and the promulgation of multidisciplinary pulmonary embolism teams show great promise to improve management and outcomes of acute pulmonary embolism (PE). However, the absence of randomized evidence and lack of consensus leads to tremendous variations in treatment and compromises the wide implementation of new innovations. Moreover, the changing landscape of health care, where quality, cost, and accountability are increasingly relevant, dictates that a broad spectrum of outcomes of care must be routinely monitored to fully capture the impact of modern PE treatment.

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The discovery of the growth hormone secretagogues (GHS) and the reverse pharmacology leading to the discovery of GHS receptor which enabled the identification of ghrelin as the natural ligand for the receptor have opened a new horizon in growth hormone (GH) physiology, pathophysiology, and therapeutics. Major progress has been made and we now have orally active GHS which are able to restore optimal pulsatile GH secretion which cannot be overstimulated as insulin-like growth factor feedback regulates the peaks to the optimum level. This enables GH to be restored in the older to levels normally seen in 20- to 30-year-old people; this leads to an increase in fat-free mass and redistribution of fat to the limbs.

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Studying fossils from a mass-mortality event reveals evidence for sexual dimorphism and, unusually, equal numbers of males and females in a herd of dinosaurs.

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Objectives: Venous thromboembolism (VTE) is a common nosocomial condition, developing frequently in overweight and obese patients. VTE prophylaxis with weight-based enoxaparin dosing may be more effective than the standard dosing regimen for overweight and obese patients; however, weight-based dosing is not practiced routinely. In this pilot study we sought to evaluate prophylactic anticoagulation regimens used for VTE prevention in overweight and obese patients on the Orthopedic-Medical Trauma (OMT) service to inform the need for modification of dosing practices.

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Background: Venous Thromboembolism (VTE) is a serious complication after free tissue transfer to the head and neck (H&N). However, an optimal antithrombotic prophylaxis protocol is not defined in the literature. Enoxaparin 30 mg twice daily (BID) and heparin 5000 IU three times daily (TID) are among the most commonly used regimens for chemoprophylaxis.

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Background: Intravascular large B-cell lymphoma (IVLBCL) is a rare subtype of extranodal B-cell lymphoma, which has traditionally been associated with poor outcomes. Despite increasing recognition, IVLBCL requires a high degree of clinical suspicion on the part of the clinician for its diagnosis.

Case Series: We present four patient cases: A 69-year-old female with constitutional symptoms and cognitive decline; a 78-year-old female with kidney injury and constitutional symptoms whose disease rapidly progressed to multiorgan failure and death; a 70-year-old asymptomatic female with an incidentally found, enlarged thyroid; and a 63-year-old male with cytopenia and constitutional symptoms.

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Chronic/refractory immune thrombocytopenia (ITP) is a rare and pathophysiologically heterogeneous disorder with variable responsiveness to available treatments. Sutimlimab, a first-in-class humanized monoclonal anti-C1s IgG4 antibody, selectively inhibits the classical pathway. This phase 1 study (NCT03275454) assessed the safety, efficacy, pharmacokinetics, and pharmacodynamics of biweekly sutimlimab in patients with chronic/refractory ITP with an inadequate response to ≥2 therapies (platelet count ≤ 30 × 109/L).

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Background And Objectives: Activation of ghrelin receptor growth hormone secretagogue receptor (GHS-R) by endogenous or synthetic ligands amplifies pulsatile release of growth hormone (GH) and enhances food intake, very relevant to development and growth. GHS-R is a G-protein coupled receptor that has great druggable potential. Understanding the precise ligand and receptor interactions is crucial to advance the application of GHS-R.

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Background Existing evidence indicates Black patients have higher incidence of pulmonary embolism (PE) and PE-related mortality compared with other races/ethnicities, yet disparities in presenting severity and treatment remain incompletely understood. Methods and Results We retrospectively queried a multihospital healthcare system for all hospitalizations for acute PE (2012-2019). Of 10 329 hospitalizations, 8743 met inclusion criteria.

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Azhdarchid pterosaurs, the largest flying vertebrates, remain poorly understood, with fundamental aspects of their palaeobiology unknown. X-ray computed tomography reveals a complex internal micro-architecture for three-dimensionally preserved, hyper-elongate cervical vertebrae of the Cretaceous azhdarchid pterosaur, sp. Incorporation of the neural canal within the body of the vertebra and elongation of the centrum result in a "tube within a tube" supported by helically distributed trabeculae.

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Growth hormone secretagogue receptor (GHS-R) is widely known to regulate food intake and adiposity, but its role in glucose homeostasis is unclear. In this study, we investigated the expression of GHS-R in mouse pancreatic islets and its role in glycemic regulation. We used Ghsr-IRES-tauGFP mice, with Green Fluorescent Protein (GFP) as a surrogate for GHS-R, to demonstrate the GFP co-localization with insulin and glucagon expression in pancreatic islets, confirming GHS-R expression in β and α cells.

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A recent study found that approximately 1 in every 6 patients hospitalized for the 1st episode of syncope had an underlying pulmonary embolism (PE). As current guidelines do not strongly emphasize evaluation for PE in the workup of syncope, we hypothesize that there might be a higher rate of 30-day readmission due to untreated venous thromboembolism (VTE). The objective of this study is to measure the 30-day readmission rate due to VTE and identify predictors of 30-day readmission with VTE among syncope patients.

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Venous thromboembolism (VTE) is an important cause of morbidity and mortality in the United States (US). The increasing rates of VTE in the US resulted in the surgeon general issuing a call to action to reduce VTE in 2008. The objective of our study was to analyze the national trends of inpatient VTE in the US from 2004 to 2013 (5 years before and after 2008).

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Anti-factor Xa (anti-Xa) monitoring of unfractionated heparin (UFH) is associated with less time to achieve therapeutic anticoagulation compared to the activated partial thromboplastin time (aPTT). However, it is unknown whether clinical outcomes differ between these methods of monitoring. The aim of this research was to compare the rate of venous thrombosis and bleeding events in patients that received UFH monitored by anti-Xa compared to the aPTT.

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Endocannabinoids acting on the cannabinoid-1 receptor (CBR) or ghrelin acting on its receptor (GHS-R) both promote alcohol-seeking behavior, but an interaction between the two signaling systems has not been explored. Here, we report that the peripheral CBR inverse agonist JD5037 reduces ethanol drinking in wild-type mice but not in mice lacking CBR, ghrelin peptide or GHS-R. JD5037 treatment of alcohol-drinking mice inhibits the formation of biologically active octanoyl-ghrelin without affecting its inactive precursor desacyl-ghrelin.

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This pair of studies investigated steering in the absence of continuous visual information. In a driving simulator, participants steered a curving path that was displayed either continuously or intermittently. Optic flow conditions were manipulated to alter the nature of the heading information with respect to the path being steered.

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Introduction: Performing therapeutic plasma exchange (TPE) with albumin replacement decreases coagulation factor and platelet levels. No defined guidelines exist regarding laboratory testing to assess hemostasis in patients undergoing TPE.

Materials And Methods: A survey to evaluate hemostasis testing with TPE was distributed using online survey software.

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Background: Patients undergoing therapeutic plasma exchange (TPE) may present with risks for hemorrhage or thrombosis. Use of replacement fluids devoid of coagulation factors will decrease factor levels and platelet levels. There are no established guidelines for hemostasis management in these situations.

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Objective: Whether cerebrovascular regulation is different in patients with controlled high blood pressure (HBP) with and without small vessel disease (SVD).

Methods: Sixty-seven healthy controls (mean age ± SD, 45 ± 16 years; 30 women, 37 men) and 40 patients (mean age, 64 ± 13 years; 14 women, 26 men) with HBP and different stages of SVD, underwent simultaneous recordings of the spontaneous fluctuations of BP, blood flow velocity (CBFV) in both middle cerebral arteries (MCA), and of end-tidal CO2 (ETCO2). Coherence and transfer function gain and phase between BP and CBFV were assessed in the frequency ranges of VLF (0.

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Clinician educators at academic medical centers often lack the community, mentorship, and faculty development to support their missions around education scholarship and teaching. Inadequate support for clinician educators can lead to professional dissatisfaction and slowed academic advancement. In 2014, ASH conducted a needs assessment of medical school hematology course directors, hematology-oncology fellowship program directors, and other ASH members identified as educators to determine this community's desire for faculty development in medical education.

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Background: Little data exist on the use of direct oral anticoagulant (DOAC) factor Xa inhibitors for submassive pulmonary embolism (PE) after catheter-directed thrombolysis (CDT). The objective of this evaluation was to determine whether the transition from parenteral anticoagulation to DOACs for submassive PE after CDT would decrease hospital length of stay (LOS) compared to warfarin.

Methods: A retrospective review of patients diagnosed with submassive PE who underwent CDT was conducted from January 1, 2012, to February 28, 2017.

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The purpose of this study was to compare the performance of anti-factor Xa concentration versus activated partial thromboplastin time (aPTT) monitoring with multiple indication-specific heparin nomograms. This was a prospective, nonrandomized study with historical control at a large academic medical center. A total of 201 patients who received intravenous heparin in the cardiology units were included.

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Objective: The aim of our study was to evaluate the adequacy and quality of the bone marrow (BM) obtained by OnControl powered drill (P-group) and to compare it with manual procedure (M-group).

Design: Retrospective analysis was done on 75 BM specimens; Jamshidi needle (n=44) and OnControl (n=31). Biopsy length after fixation, evaluable marrow length and total area, and fragmentation, aspiration and marrow dropout artefacts were compared.

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It is well recognized that G-protein-coupled receptors (GPCRs) can activate Ras-regulated kinase pathways to produce lasting changes in neuronal function. Mechanisms by which GPCRs transduce these signals and their relevance to brain disorders are not well understood. Here, we identify a major Ras regulator, neurofibromin 1 (NF1), as a direct effector of GPCR signaling via Gβγ subunits in the striatum.

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