Co-exposure of the Mycotoxins Lolitrem B and Ergovaline in Steers Fed Perennial Ryegrass ( Lolium perenne) Straw: Metabolic Characterization of Excreta.

Past research showed a strong linear correlation between levels of the mycotoxins lolitrem B (LB, a tremorgen) and ergovaline (EV, an ergot alkaloid and potent vasoconstrictor) in perennial ryegrass (PRG) forage. The purpose of this study was to characterize the excretion of these two compounds in beef cattle consuming PRG straw and to utilize liquid chromatography-tandem mass spectrometry to investigate the metabolism of LB and EV in excreta. Four groups of steers ( n = 6/group) were fed endophyte-infected PRG for 64 days (2256/638, 1554/373, 1012/259, or 247/<100 μg/kg LB/EV).

Application of Paper Strip Extraction in Combination with LC-MS-MS in Pharmacokinetics.

Recent advances in sampling techniques in the pharmaceutical industry sparked significant interest in applying improvements to extraction methods for greater analyte detection and quantitation. In particular, the dried blood spot (DBS) sampling technique has numerous advantages compared to traditional methods such as liquid-liquid extraction, including the use of small sample volumes, less sample processing, and less exposure to toxic solvents (ether, methyl -butyl ether [MTBE], and dichloromethane). In this article, we discuss the adaptation of DBS technology to develop and validate a novel paper strip extraction method for the analysis of natural product metabolites in biological samples obtained from a human pharmacokinetic study of xanthohumol, a hop prenylflavonoid.

Ruminal bioremediation of the high energy melting explosive (HMX) by sheep microorganisms.

The ability of ruminal microorganisms to degrade octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (high melting explosive, HMX) as consortia from whole rumen fluid (WRF), and individually as 23 commercially available ruminal strains, was compared under anaerobic conditions. Compound degradation was monitored by high-performance liquid chromatography, followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) for delineation of the metabolic pathway. In WRF, 30 μM HMX was degraded to 5 μM HMX within 24 h.

Validation of a novel extraction method for studying hexahydro-1,3,5-trinitro-1,3,5 triazine (RDX) biodegradation by ruminal microbiota.

A simple, fast liquid-liquid extraction method was developed for studying hexahydro-1,3,5-trinitro-1,3,5 triazine (RDX) biodegradation using small sample volumes. The method was tested in vitro with anaerobic incubations of RDX with whole rumen fluid (WRF) and a commercial Sporanaerobacter acetigenes strain in methanogenic media for RDX. Additionally, validation experiments were conducted in deionized water in order to show applicability toward various aqueous matrices.

Anaerobic bioremediation of RDX by ovine whole rumen fluid and pure culture isolates.

The ability of ruminal microbes to degrade the explosive compound hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in ovine whole rumen fluid (WRF) and as 24 bacterial isolates was examined under anaerobic conditions. Compound degradation was monitored by high-performance liquid chromatography analysis, followed by liquid chromatography-tandem mass spectrometry identification of metabolites. Organisms in WRF microcosms degraded 180 μM RDX within 4 h.

Perceptual tests of rhythmic similarity: I. Mora rhythm.

Listeners rely on native-language rhythm in segmenting speech; in different languages, stress-, syllable- or mora-based rhythm is exploited. The rhythmic similarity hypothesis holds that where two languages have similar rhythm, listeners of each language should segment their own and the other language similarly. Such similarity in listening was previously observed only for related languages (English-Dutch; French-Spanish).

Mild cognitive impairment: evaluation with 4-T functional MR imaging.

Purpose: To prospectively assess abnormalities in brain activation patterns during encoding and retrieval in subjects with mild cognitive impairment by using 4-T functional magnetic resonance (MR) imaging.

Materials And Methods: The institutional review board approved this HIPAA-compliant study; all subjects gave written informed consent. Twenty patients with mild cognitive impairment (12 men, eight women; mean age, 75.

Preparation of monoclonal antibodies against human telomerase.

Telomerase, a ribonucleoprotein enzyme that extends telomeres of eukaryotic chromosomes, consists of the catalytic protein submit telomerase reverse transcriptase (TERT) and a telomerase RNA subunit. Nearly 85% of human tumors have tested positive for high telomerase activity. Telomerase activity is very low or not present in normal cells, whereas it is up-regulated in immortalized cells.

Cross-protection in NYVAC-HIV-1-immunized/HIV-2-challenged but not in NYVAC-HIV-2-immunized/SHIV-challenged rhesus macaques.

Objectives: Immunization with attenuated poxvirus-HIV-1 recombinants followed by protein boosting had protected four of eight rhesus macaques from HIV-2SBL6669 challenge. The present study was designed to confirm this result and to conduct the reciprocal cross-protection experiment.

Methods: Twenty-four macaques were primed with NYVAC (a genetically attenuated Copenhagen vaccinia strain) recombinants with HIV-1 and HIV-2 env and gag-pol or NYVAC vector alone and boosted with homologous, oligomeric gp160 proteins or adjuvant only.

Factors associated with slow disease progression in macaques immunized with an adenovirus-simian immunodeficiency virus (SIV) envelope priming-gp120 boosting regimen and challenged vaginally with SIVmac251.

Rhesus macaques were immunized with a combination vaccine regimen consisting of adenovirus type 5 host range mutant-simian immunodeficiency virus envelope (Ad5hr-SIVenv) recombinant priming and boosting with native SIV gp120. Upon intravaginal challenge with SIVmac251, both persistently and transiently viremic animals were observed (S. L.

Vaccine protection against a heterologous, non-syncytium-inducing, primary human immunodeficiency virus.

Vaccine-induced protection of chimpanzees against laboratory-adapted and syncytium-inducing, multiply passaged primary human immunodeficiency virus type 1 (HIV-1) isolates, but not against non-syncytium-inducing, minimally passaged ones, has been demonstrated. Following challenge with such an isolate, HIV-15016, we obtained complete protection in one of three chimpanzees previously protected against low- and high-dose HIV-1SF2 exposures after immunization with an adenovirus-HIV-1MN gp160 priming-HIV-1SF2 gp120 boosting regimen. At challenge, the protected chimpanzee exhibited broad humoral immunity, including neutralizing antibody activity.

Effect of topically applied sulphur mustard on guinea pig liver.

The study revealed that topically applied sulphur mustard, which is a potent blistering agent with mutagenic and carcinogenic properties, is also hepatotoxic. It produces severe steatosis and other pathological alterations, accompanied by biochemical changes. There is a significant rise in the levels of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvate transaminase (GPT) after exposure.

Block of Tat-mediated transactivation of tumor necrosis factor beta gene expression by polymeric-TAR decoys.

The tat gene product (Tat) of human immunodeficiency virus type 1 (HIV-1) is an early regulatory protein which transactivates HIV-1 gene expression by interacting with the trans-activation response element (TAR) present in the HIV-1 long terminal repeat (LTR). In HIV-1-infected cells Tat can also activate the expression of tumor necrosis factor (TNF). Recent results indicate that essential for this effect is the interaction of Tat with a TAR-like structure present in the TNF beta messenger RNA leader region that closely resembles the TAR of the HIV-LTR.

Differentiation and uteroglobin gene expression by novel rabbit endometrial cell lines.

A clear understanding of the mechanism of differentiation of mammalian endometrial epithelia would significantly improve our knowledge of embryo implantation and placentation. An ideal model for such studies would be immortal endometrial epithelial cell lines which express a well characterized, steroid-responsive, differentiation-specific gene in vitro. We characterized two cell lines which are temperature-sensitive for differentiation.

N-linked protein glycosylation in the rat parotid gland during aging.

N-Linked protein glycosylation was examined in vitro in dispersed rat parotid acinar cells from young adult (3-6 months) and aged (22-24 months) rats. A small decrease in general protein production was observed with cells from aged animals (approximately 20% lower incorporation of [14C]leucine into 10% CCl3 COOH insoluble protein during continuous pulse labeling). Incorporation of [3H]mannose into N-linked glycoproteins by aged cells was further reduced (approximately 35%).

Drug use in college students: a test of sociodemographic and reference group models of explanation.

This study examined the importance of reference group variables in the understanding of drug use in college students. Other studies have investigated the role of peer orientation, and this study further elaborates on the issue by specifically looking into parents and peers as reference groups for the students. This study supports the importance of reference group variables in understanding the students' use of marijuana and/or hashish.