Publications by authors named "David Worth"

Background: Tumors of various sizes and locations can create a treatment dilemma in achieving adequate surgical margins when sufficient free tissue is not available for closure. Extravascular local adjunctive chemotherapy has been investigated clinically to aid in achieving local tumor control in animals with naturally occurring neoplastic disease. Local chemotherapy can be an alternative primary or a local adjunctive treatment.

View Article and Find Full Text PDF

Objective: To evaluate the intra-lot and inter-lot consistency and total carboplatin elution over 25 days from carboplatin-impregnated calcium sulfate hemihydrate (C-I CSH) beads manufactured in a clinic setting.

Study Design: In vitro elution study.

Methods: Two volumes of carboplatin were mixed with CSH to yield 4 mg and 8 mg C-I CSH doses.

View Article and Find Full Text PDF

OBJECTIVE To identify risk factors for temporary tracheostomy tube placement (TTTP) following surgery for alleviation of signs associated with brachycephalic obstructive airway syndrome (BOAS) in dogs. DESIGN Retrospective case-control study. ANIMALS 122 client-owned dogs with BOAS that underwent surgery to alleviate clinical signs (BOAS surgery).

View Article and Find Full Text PDF

Retroorbital blood collection is a common technique in laboratory rodents due to the ease with which it can be performed and the sample volumes obtained for subsequent blood analyses. However, its use has been discouraged recently due to aesthetic discomfort and anecdotal reports of potential for ocular injury during blood collection. We hypothesized that a single standardized session of in-person training would be sufficient to learn the appropriate technique and minimize the likelihood for adverse outcomes.

View Article and Find Full Text PDF

Patients presenting with recalcitrant symptoms, which are resistant to a range of physical interventions over an extended period of time, need to be examined with care. A 'forensic' approach to the assessment of these patients, with a sensitive approach to the results of the test procedures is required to ensure the practitioner does not miss the more obscure causes. This case report presents a patient who was referred for a clinical assessment for long standing scapular pain, which had been labelled myofascial pain.

View Article and Find Full Text PDF

Many of the complex systems found in biology are comprised of numerous components, where interactions between individual agents result in the emergence of structures and function, typically in a highly dynamic manner. Often these entities have limited lifetimes but their interactions both with each other and their environment can have profound biological consequences. We will demonstrate how modelling these entities, and their interactions, can lead to a new approach to experimental biology bringing new insights and a deeper understanding of biological systems.

View Article and Find Full Text PDF

Recent work demonstrates that nearshore oceanography can generate strong variation in the delivery of resources (nutrients and larvae) to benthic marine communities over spatial scales of tens to hundreds of kilometers. Moreover, variation in the strength of these bottom-up inputs is often spatially consistent, linked to regional centers of upwelling, coastal topography, and other stable features of the coastline. Whereas the ecological effects of these oceanographic links are increasingly clear, the possibility that these same bottom-up forces might impose spatially varying selection on consumers has not been addressed.

View Article and Find Full Text PDF

The extent to which community processes can be generalized from local field studies to larger spatial scales remains a contentious issue. The search for broad generality can be hampered when species interactions vary geographically, a common phenomenon attributed to a wide range of underlying ecological factors. Less attention has been directed toward understanding the additional role that evolutionary processes may play in modifying the way that pairs of species interact over large spatial scales.

View Article and Find Full Text PDF

Rhodococcus equi is a rare form of opportunistic infection in humans, more common in the immunocompromised. We present a case of pulmonary infection and subsequent cerebral abscess secondary to R. equi in a patient receiving immunosuppression for a c-ANCA positive vasculitis.

View Article and Find Full Text PDF

Cyclosporin A (CyA) toxicity is a common occurrence in pediatric organ transplant patients. We hypothesized that reduced mdr1a expression in newborn and developing mice would affect CyA accumulation within organs and/or toxicity. For functional studies, CyA was administered (5 mg kg(-1) i.

View Article and Find Full Text PDF

The objective of this study was to compare urinary excretion patterns of two cannabinoid metabolites in subjects with a history of chronic marijuana use. The first metabolite analyzed was nor-9-carboxy-delta9-tetrahydrocannabinol (delta9-THC-COOH), the major urinary cannabinoid metabolite that is pharmacologically inactive. The second metabolite 11-OH-delta9-THC is an active cannabinoid metabolite and is not routinely measured.

View Article and Find Full Text PDF

Subjects with a history of chronic marijuana use were screened for cannabinoids in urine specimens with the EMIT((R)) II Plus cannabinoids assay with a cut-off value of 50 ng/ml. All presumptively positive specimens were submitted for confirmatory analysis for the major urinary cannabinoid metabolite (Delta(9)-THC-COOH) by GC-MS with a cut-off value of 15 ng/ml. Creatinine was analyzed in each specimen as an index of dilution.

View Article and Find Full Text PDF

Metabolic pathways in humans have been elucidated for most therapeutic drugs, drugs of abuse, and various chemical/solvents. In most drug overdose cases and chemical exposures, laboratory analysis is directed toward identification and quantitation of the unchanged drug or chemical in a biologic fluid such as serum or whole blood. Specifically, most clinical laboratories routinely screen and quantitate unchanged methanol and/or ethylene glycol in suspected poisonings without toxic metabolite analysis.

View Article and Find Full Text PDF

Drug testing in substance abuse treatment programs is focused on urine analysis of parent drugs and major metabolites. Huestis reported that serial monitoring of the major urinary cannabinoid metabolite (delta9-THC-COOH)-to-creatinine ratios in paired urine specimens (collected at least 24 hours apart) could differentiate new marijuana or hashish use from residual cannabinoid metabolite excretion in urine after previous drug use. Subjects with a history of chronic marijuana use were screened for cannabinoids in urine over several months by an enzyme immunoassay (EMIT) with a cut-off value of 50 ng/mL.

View Article and Find Full Text PDF

Objective: A decreased serum albumin level predicts poor survival in end-stage renal failure. Hypoalbuminemia is multifactorial and related to poor nutrition, inflammation, and comorbid disease. Overhydration is also common in renal replacement therapy patients, and hemodilution may also contribute to a low serum albumin level.

View Article and Find Full Text PDF