Publications by authors named "Doll W"

Background: Common cold symptoms may be mitigated by products in caplet, nasal spray, and oral solution formulations, although variations exist in the bioavailability of the active ingredients contained within these products. Rapid gastric emptying (GE) of these active ingredients is important for reducing the delay between drug absorption and onset of cold symptom relief. Hot drink cold remedies are associated with greater comfort and may enhance the bioavailability of active ingredients.

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Background: Ulimorelin, a small molecule ghrelin agonist and prokinetic agent, was effective in animal models of gastroparesis and delayed transit. However, employing once daily administration, it failed in clinical trials of postoperative ileus (POI), a condition in which colonic motility recovers last. The aim of this study was to evaluate drug dosing and regional differences in drug activity between stomach and colon.

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There are several benefits of oral immunization including the ability to elicit mucosal immune responses that may protect against pathogens that invade through a mucosal surface. Our understanding of human immune biology is hampered by the difficulty in isolating mucosal cells from humans, and the fact that animal models may or may not completely mirror human intestinal immunobiology. In this human pharmacodynamic study, a novel adenovirus vector-based platform expressing influenza hemagglutinin was explored.

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Aims: To assess the accuracy and reliability of the two most widely used continuous glucose monitoring (CGM) systems.

Methods: We studied the Dexcom®G4 Platinum (DG4P; Dexcom, San Diego, CA, USA) and Medtronic Paradigm Veo Enlite system (ENL; Medtronic, Northridge, CA, USA) CGM systems, in 24 patients with type 1 diabetes. The CGM systems were tested during 6-day home use and a nested 6-h clinical research centre (CRC) visit.

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Objective: To evaluate the feasibility of day and night closed-loop insulin delivery in adults with type 1 diabetes under free-living conditions.

Research Design And Methods: Seventeen adults with type 1 diabetes on insulin pump therapy (means ± SD age 34 ± 9 years, HbA1c 7.6 ± 0.

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Objective: To compare two validated closed-loop (CL) algorithms versus patient self-control with CSII in terms of glycemic control.

Research Design And Methods: This study was a multicenter, randomized, three-way crossover, open-label trial in 48 patients with type 1 diabetes mellitus for at least 6 months, treated with continuous subcutaneous insulin infusion. Blood glucose was controlled for 23 h by the algorithm of the Universities of Pavia and Padova with a Safety Supervision Module developed at the Universities of Virginia and California at Santa Barbara (international artificial pancreas [iAP]), by the algorithm of University of Cambridge (CAM), or by patients themselves in open loop (OL) during three hospital admissions including meals and exercise.

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BMS-663068 is a phosphonooxymethyl ester prodrug under development for the treatment of HIV/AIDS. The prodrug is designed to overcome the solubility-limited bioavailability of the active moiety, BMS-626529. BMS-663068 is not absorbed from the gastrointestinal (GI) tract and requires enzymatic conversion by alkaline phosphatase to BMS-626529 immediately before absorption.

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Objective: This study assessed the accuracy and reliability of three continuous glucose monitoring (CGM) systems.

Research Design And Methods: We studied the Animas® (West Chester, PA) Vibe™ with Dexcom® (San Diego, CA) G4™ version A sensor (G4A), the Abbott Diabetes Care (Alameda, CA) Freestyle® Navigator I (NAV), and the Medtronic (Northridge, CA) Paradigm® with Enlite™ sensor (ENL) in 20 patients with type 1 diabetes mellitus. All systems were investigated both in a clinical research center (CRC) and at home.

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Remogliflozin etabonate (RE) is the prodrug of remogliflozin (R), an inhibitor of renal glucose transport designed to reduce blood glucose concentrations for the treatment of type 2 diabetes. This open-label, randomized, single-dose, four-way crossover study, (with one add-on arm) in eight healthy men evaluated the regional gastrointestinal absorption of RE, the systemic appearance of the active entity R, and an active metabolite, GSK279782. The InteliSite(®) Companion Capsule was used to administer a single dose of RE 100 mg to the mid-small intestine or cecum/colon.

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Clinical point of care testing often needs plasma instead of whole blood. As centrifugation is labor intensive and not always accessible, filtration is a more appropriate separation technique. The complexity of whole blood is such that there is still no commercially available filtration system capable of separating small sample volumes (10-100 μl) at the point of care.

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The purpose of this work was to assess the pharmacokinetics and safety of lisdexamfetamine dimesylate (LDX) delivered and released regionally in the gastrointestinal (GI) tract. In this open-label, randomized, crossover study, oral capsules and InteliSite delivery capsules containing LDX (50 mg) with radioactive marker were delivered to the proximal small bowel (PSB), distal SB (DSB), and ascending colon (AC) during separate periods. Gamma scintigraphy evaluated regional delivery and GI transit.

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Background And Objective: Data on pharmacokinetic parameters of the prodrug stimulant lisdexamfetamine dimesylate via alternate routes of administration are limited. The pharmacokinetics of d-amphetamine derived from lisdexamfetamine dimesylate after single oral (PO) versus intranasal (IN) administration of lisdexamfetamine dimesylate were compared.

Methods: In this randomized, two-period, crossover study, healthy men without a history of substance abuse were administered single PO or IN (radiolabelled with ≤100 μCi (99m)Tc-diethylenetriamine-pentaacetic acid and confirmed by scintigraphy) lisdexamfetamine dimesylate 50 mg ≥7 days apart.

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The concept of complexity is a popular and contentious topic. Just what is complexity? What does it mean to 'think complexly'? This paper addresses both of these issues. Complexity thinking is impossible to define with any precision as it deals not only with change, dynamic change, evergoing, but with transformative change.

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Background: The aim of this study was to investigate the performance of the enhanced Model Predictive Control (eMPC) algorithm for glycemic control in medical critically ill patients for the whole length of intensive care unit (ICU) stay.

Methods: The trial was designed as a single-center, open, noncontrolled clinical investigation in a nine-bed medical ICU in a tertiary teaching hospital. In 20 patients, blood glucose (BG) was controlled with a laptop-based bedside version of the eMPC.

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In the past decade deep brain stimulation (DBS)-the application of electrical stimulation to specific target structures via implanted depth electrodes-has become the standard treatment for medically refractory Parkinson's disease and essential tremor. These diseases are characterized by pathological synchronized neuronal activity in particular brain areas. We present an external trial DBS device capable of administering effectively desynchronizing stimulation techniques developed with methods from nonlinear dynamics and statistical physics according to a model-based approach.

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The present work was carried out to study the deposition patterns and clearance of technetium-99m (99mTc) DTPA labeled cromolyn sodium (CS) solutions when administered from two different CS nasal products using gamma scintigraphy. Five healthy volunteers received a single dose with complete crossover design involving treatment A (test formulation) and treatment B (reference formulation). The deposition patterns as well as the changes in distribution of the radiolabeled CS solutions due to the mucociliary transport were monitored by gamma scintigraphy.

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Human pharmacoscintigraphic behavior of two tablets and a capsule formulation of a high dose, poorly water soluble, highly permeable, micronized drug (efavirenz) was investigated. The tablets and capsule, prepared with samarium oxide and neutron activated to produce radioactive samarium-153, were evaluated for their in vivo disintegration and gastrointestinal (GI) transit in healthy subjects under fasted condition. Scintigraphic images were acquired to coincide with blood sampling times to assess the plasma concentration-time profile in relation to in vivo disintegration and GI transit.

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Improved surface-based geophysical technologies that are commercially available provide a new level of detail that can be used to guide ground water remediation. Surface-based multielectrode resistivity methods and tomographic seismic refraction techniques were used to image to a depth of approximately 30 m below the surface at the Natural and Accelerated Bioremediation Research Field Research Center. The U.

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Aims: The aims of the study were to evaluate the bioavailability of didanosine from the encapsulated enteric coated beads (1 x 200 mg; enteric beads) and enteric coated mini-tablets (4 x 50 mg; enteric tablet) formulations relative to the chewable/dispersible buffered tablets (2 x 100 mg; buffered tablet), and to study their rate of gastrointestinal transit.

Methods: This was a single-dose, randomized, three-way crossover study in 18 healthy male volunteers. A 200 mg dose of didanosine was given in each period and each formulation contained a gamma radiation-emitting isotope.

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Purpose: Evaluate if crosslinked hard gelatin capsules (HGCs) having different in vitro dissolution profiles changed in vivo release times or altered bioavailability of a drug marker; assess if a two-tier dissolution test (with and without enzyme) predicted in vivo performance.

Methods: Two classifications of stressed HGCs were artificially produced by exposure to formaldehyde (HCHO). HGCs were categorized as, a) pass/pass (p/p) which met in vitro dissolution criterion (75% drug dissolution at 45 min), b) moderately crosslinked fail/pass (f/p) which failed dissolution criterion in the absence of enzymes and passed in the presence of enzymes, and c) severely crosslinked fail/fail (f/f) which failed in vitro standards with or without enzymes.

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The study was conducted to assess the bioavailability of avitriptan after a standard high fat meal, in relation to gastrointestinal transit. Six healthy male subjects were enrolled in a four-period study with a partial replicate design where each was administered 150-mg avitriptan capsule (i) after an overnight fast, (ii) 5 min after a standard high-fat breakfast, and (iii) 4 hr after a standard high fat breakfast. The treatment administered in Period 3 was repeated in Period 4 to assess intrasubject variations in pharmacokinetics and gastrointestinal (GI) transit.

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Short-lived gamma emitting radioisotopes can be incorporated into polylactide/glycolide polymeric microspheres with various specific activities for possible use in understanding the in-vivo deposition, distribution and clearance of microparticulate drug carrier systems. The incorporated radiolabel is stable with negligible leaching out of the microspheres. These microspheres are suitable for studying the oral uptake of particles, lung distribution after inhalation delivery and evaluation of in-vivo fate following parenteral administration in systemic circulation or in specific tissue compartments.

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In this paper the prevalence of Legionella in water samples from cold and warm water supply systems made of copper, iron and polyethylene was determined. Water supplied by copper pipes revealed to be nearly free of Legionella (only 2% of probes positive), but water from iron (90%) or polyethylene pipes (65% probes positive) proved to be heavily contaminated. The 82 isolates were identified as Legionella pneumophila, one from serogroup 1, the others from serogroup 4.

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