Publications by authors named "David E Smith"

Introduction: In moderate to high-risk surgical procedures, 15-25% of patients develop a postoperative surgical site infection. Intraoperative incisional wound irrigation has the potential to reduce surgical site infections, and additional randomised controlled trials are required to provide evidence of effectiveness.

Methods And Analysis: This protocol describes a pragmatic, adaptive, participant and adjudicator-blinded trial at 13 sites in Canada in up to 2500 participants.

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Ectopic acromegaly is a rare condition caused by extrapituitary central or peripheral neuroendocrine tumours (NET) that hypersecrete GH or, more commonly, GHRH. It affects less than 1% of acromegaly patients and a misdiagnosis of classic acromegaly can lead to an inappropriate pituitary surgery. Four types of ectopic acromegaly have been described: 1) Central ectopic GH-secretion: Careful cross-sectional imaging is required to exclude ectopic pituitary adenomas.

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Article Synopsis
  • The study investigates how well dupilumab controls atopic dermatitis (AD) in children, adolescents, and adults, focusing on the factors influencing patient responses to the treatment.
  • Data from multiple clinical trials involving over 2,000 participants were analyzed to determine how drug exposure affects treatment efficacy, measured by EASI and IGA scores.
  • Findings revealed that older age, higher body weight, lower baseline chemokine levels, and Asian race were linked to slightly lower responses, with children showing better drug effects compared to adults at similar drug concentrations.
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This review is a revisit of various oral drug absorption models developed in the past decades, focusing on how to incorporate the physiological dynamics in the upper gastrointestinal (GI) tract. For immediate-release oral drugs, GI absorption is a critical input of drug exposure and subsequent human body response, yet difficult to model largely due to the complex GI environment. One of the biggest hurdles lies at capturing the high within-subject variability (WSV) of bioavailability measures, which can be mechanistically explained by the GI physiological dynamics.

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The rate and extent of drug dissolution and absorption from a solid oral dosage form depend largely on the fluid volume along the gastrointestinal tract. Hence, a model built upon the gastric fluid volume profiles can help to predict drug dissolution and subsequent absorption. To capture the great inter- and intra-individual variability (IAV) of the gastric fluid volume in fasted human, a stochastic differential equation (SDE)-based mixed effects model was developed and compared with the ordinary differential equation (ODE)-based model.

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The prodrug mycophenolate mofetil (MMF), which is presystemically hydrolyzed into the pharmacologically active compound mycophenolic acid (MPA), has been widely used for the prophylaxis of acute allograft rejection in solid organ transplantation. However, the huge variability in the plasma concentration level makes the development of MMF drug products difficult due to the great challenge of meeting the traditional bioequivalence (BE) limits. Numerous models have been developed in the past decade to explain the variability, with the emphasis on characterizing the enterohepatic circulation.

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In 2021, over 100,000 people died prematurely from opioid overdoses. Neuropsychiatric and cognitive impairments are underreported comorbidities of reward dysregulation due to genetic antecedents and epigenetic insults. Recent genome-wide association studies involving millions of subjects revealed frequent comorbidity with substance use disorder (SUD) in a sizeable meta-analysis of depression.

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Background And Objective: The pharmacokinetics (PK) of methylphenidate (MPH) differ significantly among individuals. Carboxylesterase 1 (CES1) is the primary enzyme metabolizing MPH, and its function is affected by genetic variants, drug-drug interaction (DDI), and sex. The object of this study is to evaluate CES1 pharmacogenetics as related to MPH metabolism using human liver samples and develop a physiologically-based pharmacokinetic (PBPK) modeling approach to investigate the influence of CES1 genotypes and other factors on MPH PK.

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This commentary explores the neurobiology of spirituality and asks whether it is possible or desirable to apply genetic engineering to increase human spiritual and religious experience - (gene-spirituality) to deal better with the ever-increasing catastrophes that face humanity? Neurological connections between spirituality and reward genes, reward deficiencies (RDS) (hypodopaminergia), the mirror neuron system, and the default mode network are examined. Some interventions from addiction medicine that may be useful to enhance the neuro-spirituality connectome identified as a cornerstone of the Purpose and Meaning of Life as Reward (PMLR) are identified as reasonable targets for interventions to treat RDS and balance DMN activity.

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In 1965, I was training in clinical toxicology in the pharmacology department of the University of California San Francisco (UCSF) and living in the Haight Ashbury. I studied various psychedelics, including LSD, mescaline, and ibogaine, in human and animal models. The psychedelics were then being used as a therapeutic drug in clinical settings and researched as a potential antipersonnel agent by the U.

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In 2016, an eConsult service was developed within a safety net health system to expand access to hepatitis C (HCV) treatment in the primary care setting. The eConsult system provides individualized treatment recommendations from specially trained primary care pharmacists and primary care physicians to primary care providers with less experience in the rapidly changing treatment of HCV. Since its launch, this service has had a large impact in expanding care to a largely homeless and low-income urban population within our health system.

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We report the development of a new type of space lidar specifically designed for missions to small planetary bodies for both topographic mapping and support of sample collection or landing. The instrument is designed to have a wide dynamic range with several operation modes for different mission phases. The laser transmitter consists of a fiber laser that is intensity modulated with a return-to-zero pseudo-noise (RZPN) code.

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Millions of Americans experience pain daily. In 2017, opioid overdose claimed 64,000 lives increasing to 84,000 lives in 2020, resulting in a decrease in national life expectancy. Chronic opioid use results in dependency, drug tolerance, neuroadaptation, hyperalgesia, potential addictive behaviors, or Reward Deficiency Syndrome (RDS) caused by a hypodopaminergia.

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A recent analysis from Stanford University suggested that without any changes in currently available treatment, prevention, and public health approaches, we should expect to have 510,000 deaths from prescription opioids and street heroin from 2016 to 2025 in the US. In a recent review, Mayo Clinic Proceedings (October 2019), Gold and colleagues at Mayo Clinic reviewed the available medications used in opioid use disorders and concluded that in private and community practice adherence is more important as a limiting factor to retention, relapse, and repeat overdose. It is agreed that the primary utilization of known opioid agonists like methadone, buprenorphine and naloxone combinations, while useful as a way of reducing societal harm, is limited by 50% of more discontinuing treatment within 6 months, their diversion, and addiction liability.

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Background: Cachexia is a debilitating, life-threatening condition whose pathology includes reduced food intake accompanied by hypermetabolism, leading to a catabolic state. The hypothalamic melanocortin system is a critical regulator of metabolic rate with effects being mediated through the melanocortin-4 receptor (MC4R). MC4R activation is also critical to the initiation and maintenance of cachexia.

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Gemcitabine is an intravenously administered anti-cancer nucleoside analogue. Systemic exposure following oral administration of gemcitabine is limited by extensive first-pass metabolism via cytidine deaminase (CDA) and potentially by saturation of nucleoside transporter-mediated intestinal uptake. An amino acid ester prodrug of gemcitabine, 5'-l-valyl-gemcitabine (V-Gem), was previously shown to be a substrate of the intestinally expressed peptide transporter 1 (PEPT1) and stable against CDA-mediated metabolism.

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The Laser Retroreflector Array for Lunar Landers (LRALL) is a small optical instrument designed to provide a target for precision laser ranging from a spacecraft in lunar orbit, enabling geolocation of the lander and its instrument suite and establishing a fiducial maker on the lunar surface. Here we describe the optical performance of LRALL at visible and near-infrared wavelengths. Individual corner cube reflectors (CCRs) within LRALL were tested for surface flatness and dihedral angle values.

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Prodrug discovery and development in the pharmaceutical industry have been hampered by a lack of knowledge of prodrug activation pathways. Such knowledge would minimize the risks of prodrug failure by enabling proper selection of preclinical animal models, prediction of pharmacogenomic variability, and identification of drug-drug interactions. Technologies for annotation of activating enzymes have not kept pace with the growing need.

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The ectopic parathyroid tissue is a frequent cause of recurrent hyperparathyroidism (HPT), accounting 16% in primary HPT and 14% in secondary cases. Although intrathoracic ectopic glands represent 25-35% of all ectopic cases, only 2% requires thoracic surgery. The aim of this study is to report a case series of patients with ectopic mediastinal HPT treated by thoracic approach in a private institution in Argentina.

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Introduction: Antimicrobial susceptibility is well characterized in monomicrobial infections, but bacterial species often coexist with other bacterial species. Antimicrobial susceptibility is often tested against single bacterial isolates; this approach ignores interactions between cohabiting bacteria that could impact susceptibility. Here, we use Pooled Antibiotic Susceptibility Testing to compare antimicrobial susceptibility patterns exhibited by polymicrobial and monomicrobial urine specimens obtained from patients with urinary tract infection symptoms.

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A set of small and lightweight laser retro-reflector arrays (LRAs) was fabricated and tested for use on lunar landers under NASA's Commercial Lunar Payload Service program. Each array contains eight 1.27-cm-diameter corner cube retro-reflectors mounted on a dome-shaped aluminum structure.

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Objective: To evaluate whether multiplex PCR-based molecular testing is noninferior to urine culture for detection of bacterial infections in symptomatic patients.

Methods: Retrospective record review of 582 consecutive elderly patients presenting with symptoms of lower urinary tract infection (UTI) was conducted. All patients had traditional urine cultures and PCR molecular testing run in parallel.

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