Bridging of a Liquid Chromatography-Tandem Mass Spectrometry Method for Oxytetracycline, Chlortetracycline, and Tetracycline in Bovine Kidney with the Official Microbial Growth Inhibition Assay.

Background: Oxytetracycline (OTC), chlortetracycline (CTC), and tetracycline (TC) are approved antibiotics used to treat bacterial infections in cattle. To ensure human food safety, a tolerance has been established for the sum of these three TC residues as 12 parts per million in bovine kidney in the United States The current official regulatory method for quantifying these antibiotics in the target organ is a labor-intensive microbiological assay.

Objective: Our laboratory developed and validated a fast, selective, and less laborious method utilizing LC-tandem mass spectrometry for the determination and confirmation of the three tetracyclines (TET) in bovine kidney.

Impact of Integrating Insulin-Like Growth Factor 1 Levels into Model for End-Stage Liver Disease Score for Survival Prediction in Hepatocellular Carcinoma Patients.

Background: Liver reserve affects survival in hepatocellular carcinoma (HCC). Model for End-Stage Liver Disease (MELD) score is used to predict overall survival (OS) and to prioritize HCC patients on the transplantation waiting list, but more accurate models are needed. We hypothesized that integrating insulin-like growth factor 1 (IGF-1) levels into MELD score (MELD-IGF-1) improves OS prediction as compared to MELD.

Clinical and prognostic significance of circulating levels of angiopoietin-1 and angiopoietin-2 in hepatocellular carcinoma.

Angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) play critical roles in angiogenesis in hepatocellular carcinoma (HCC). In addition, recent data suggest that Ang-1/Ang-2 are involved in regulating the immune response. The aim of our study was to explore the clinical prognostic significance of plasma Ang-1 and Ang-2 in HCC.

Application of time-of-flight mass spectrometry for screening of crude glycerins for toxic phorbol ester contaminants.

Since 2007, the U.S. Food and Drug Administration (FDA) has received numerous complaints of pet illnesses that may be related to the consumption of jerky pet treats.

Yttrium-90 resin microspheres as an adjunct to sorafenib in patients with unresectable hepatocellular carcinoma.

Purpose: The safety and efficacy of the combined use of sorafenib and yttrium-90 resin microspheres (Y90 RMS) to treat advanced hepatocellular carcinoma (HCC) is not well established. We determined the incidence of adverse events with this combination therapy in patients with advanced HCC at our institution and analyzed the treatment and survival outcomes.

Materials And Methods: We reviewed the records of 19 patients with Barcelona Clinic Liver Cancer class B or C HCC who underwent treatment with Y90 RMS (for 21 sessions) while receiving full or reduced doses of sorafenib between January 2008 and May 2010.

Phase II trial of bevacizumab and erlotinib as a second-line therapy for advanced hepatocellular carcinoma.

Trial Registry: Clinicaltrials.gov #NCT01180959.

Background: Early clinical studies of bevacizumab and erlotinib in advanced hepatocellular carcinoma (HCC) have a tolerable toxicity and a promising clinical outcome.

Characterization of N-glycosylation and amino acid sequence features of immunoglobulins from swine.

The primary goal of this study was to develop a method to study the N-glycosylation of IgG from swine in order to detect epitopes containing N-glycolylneuraminic acid (Neu5Gc) and/or terminal galactose residues linked in α1-3 susceptible to cause xenograft-related problems. Samples of immunoglobulin were isolated from porcine serum using protein-A affinity chromatography. The eluate was then separated on electrophoretic gel, and bands corresponding to the N-glycosylated heavy chains were cut off the gel and subjected to tryptic digestion.

Assessing contributions of nucleus accumbens shell subregions to reward-seeking behavior.

Background: The nucleus accumbens (NAc) plays a key role in brain reward processes including drug seeking and reinstatement. Several anatomical, behavioral, and neurochemical studies discriminate between the limbic-associated shell and the motor-associated core regions. Less studied is the fact that the shell can be further subdivided into a dorsomedial shell (NAcDMS) and an intermediate zone (NAcINT) based on differential expression of transient c-Fos and long-acting immediate-early gene ΔFosB upon cocaine sensitization.

Determination of ceftiofur metabolite desfuroylceftiofur cysteine disulfide in bovine tissues using liquid chromatography-tandem mass spectrometry as a surrogate marker residue for ceftiofur.

Ceftiofur is a widely used cephalosporin β-lactam antibiotic with frequently reported residue violations. This paper reports a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determining a ceftiofur metabolite, desfuroylceftiofur cysteine disulfide (DCCD), in bovine kidney, liver, and muscle tissues. Incurred tissue samples were obtained from dosed animals and analyzed to evaluate the utility of the method.

Determination of erythromycin in medicated salmonid fish feed by liquid chromatography and UV spectroscopy.

A simple, robust LC-UV method was developed to assay erythromycin in medicated salmonid feed. In this method, erythromycin was extracted from feed with acetonitrile and water, cleaned up by SPE, evaporated to dryness, reconstituted, and analyzed by LC-UV. The resulting method produced high accuracy, 82-90%, for both salmon and trout feed that represented varied pellet sizes and ingredient amounts.