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Besides the identification point system to assure adequate set-up of instrumentation, European Commission Decision 2002/657/EC includes performance criteria regarding relative ion abundances in mass spectrometry and chromatographic retention time. In confirmatory analysis, the relative abundance of two product ions, acquired in selected reaction monitoring mode, the ion ratio should be within certain ranges for confirmation of the identity of a substance. The acceptable tolerance of the ion ratio varies with the relative abundance of the two product ions and for retention time, CD 2002/657/EC allows a tolerance of 5%. Because of rapid technical advances in analytical instruments and new approaches applied in the field of contaminant testing in food products (multi-compound and multi-class methods) a critical assessment of these criteria is justified. In this study a large number of representative, though challenging sample extracts were prepared, including muscle, urine, milk and liver, spiked with 100 registered and banned veterinary drugs at levels ranging from 0.5 to 100 µg/kg. These extracts were analysed using SRM mode using different chromatographic conditions and mass spectrometers from different vendors. In the initial study, robust data was collected using four different instrumental set-ups. Based on a unique and highly relevant data set, consisting of over 39 000 data points, the ion ratio and retention time criteria for applicability in confirmatory analysis were assessed. The outcomes were verified based on a collaborative trial including laboratories from all over the world. It was concluded that the ion ratio deviation is not related to the value of the ion ratio, but rather to the intensity of the lowest product ion. Therefore a fixed ion ratio deviation tolerance of 50% (relative) is proposed, which also is applicable for compounds present at sub-ppb levels or having poor ionisation efficiency. Furthermore, it was observed that retention time shifts, when using gradient elution, as is common practice nowadays, are mainly observed for early eluting compounds. Therefore a maximum retention time deviation of 0.2 min (absolute) is proposed. These findings should serve as input for discussions on the revision of currently applied criteria and the establishment of a new, globally accepted, criterion document for confirmatory analysis. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: Recently, considerable efforts have been directed toward antivascular therapy as a new modality to treat human cancers. However, targeting a therapeutic gene of interest to the tumor vasculature with minimal toxicity to other tissues remains the objective of antivascular gene therapy. Tumor necrosis factor-alpha (TNF-alpha) is a potent antivascular agent but has limited clinical utility because of significant systemic toxicity. At the maximum tolerated doses of systemic TNF-alpha, there is no meaningful antitumor activity. Hence, the objective of this study was to deliver TNF-alpha targeted to tumor vasculature by systemic delivery to examine its antitumor activity.Methods: A hybrid adeno-associated virus phage vector (AAVP) was used that targets tumor endothelium to express TNF-alpha (AAVP-TNF-alpha). The activity of AAVP-TNF-alpha was analyzed in various in vitro and in vivo settings using a human melanoma tumor model.Results: In vitro, AAVP-TNF-alpha infection of human melanoma cells resulted in high levels of TNF-alpha expression. Systemic administration of targeted AAVP-TNF-alpha to melanoma xenografts in mice produced the specific delivery of virus to tumor vasculature. In contrast, the nontargeted vector did not target to tumor vasculature. Targeted AAVP delivery resulted in expression of TNF-alpha, induction of apoptosis in tumor vessels, and significant inhibition of tumor growth. No systemic toxicity to normal organs was observed.Conclusions: Targeted AAVP vectors can be used to deliver TNF-alpha specifically to tumor vasculature, potentially reducing its systemic toxicity. Because TNF-alpha is a promising antivascular agent that currently is limited by its toxicity, the current results suggest the potential for clinical translation of this strategy. [ABSTRACT FROM AUTHOR]

Objectives To validate and quantify the impact of insecticide-treated bednets (ITN) on malaria morbidity and mortality in Cambodia. Methods A paired, cluster-randomized trial of ITN was conducted in Rattanakiri, North East Cambodia. Thirty-four villages with a total population of 10 726 were randomized to receive deltamethrin-impregnated bednets or to control (no net provision). Cross-sectional surveys measured Plasmodium falciparum prevalence at baseline and 10 months after ITN distribution. Village malaria volunteers in control and intervention villages treated dipstick-positive P. falciparum cases with artesunate and mefloquine. The resulting passive surveillance data were used as an estimate of the incidence of clinical P. falciparum infections. Results There was a protective efficacy of 28% in P. falciparum incidence (adjusted rate ratio 0.72, 95% CI 0.47–1.08) and 9% in P. falciparum prevalence (adjusted prevalence ratio 0.91, 95% CI 0.65–1.28) in ITN relative to control villages; however, neither of these estimates reached statistical significance. Individual-level analysis indicated a greater reduction in P. falciparum prevalence among under 5-year-olds (adjusted OR = 0.63, 95% CI 0.26–1.53) compared to older individuals (interaction P = 0.042). The protective efficacy of 35% (95% CI –28, 67%) with respect to clinical P. falciparum incidence in under 5-year-olds was more pronounced than the corresponding estimates for prevalence but was again not significant. Conclusions Lack of statistical significance in the results is likely to be due to a lack of power. The analysis provides further evidence for ITN effectiveness in South East Asia, particularly among individuals under 5 years of age. [ABSTRACT FROM AUTHOR]

The principal method of malaria control in South and West Asia--indoor residual spraying--is extravagant with insecticide. A more efficient way of deploying insecticide might be to apply it on livestock since the malaria vectors in the region are highly zoophilic. A series of investigations assessed the potential of cattle treated with pyrethroid to control zoophilic mosquitoes. Permethrin, deltamethrin, and lambdacyhalothrin were applied to cattle using a sponge at concentrations of 0.5 g/m2, 0.025 g/m2, and 0.025 g/m2, respectively. 'Whole animal' insecticide bioassays that simulated natural mosquito-host contact were used to measure insecticidal and behavioural effects on wild host-seeking mosquitoes. The bioassays were performed on both sheltered and outdoor grazing animals for up to 45 days post-treatment. The possibility that treatments might cause diversion of host-seeking vectors from cattle to people nearby was also investigated. At the doses tested deltamethrin had the most pronounced and longest-lasting effect, reducing the proportion of bloodfed survivors by over 50% for the first two weeks. The majority of mosquitoes affected by the insecticide were killed before feeding. Insecticidal impact was generally lower on grazing than on sheltered animals. There was no diversion of host-seeking mosquitoes from treated cattle to nearby humans at any stage after treatment. The application of insecticide to livestock using a campaign approach may prove an effective means of controlling malaria in the region. At the doses tested deltamethrin is the most appropriate insecticide for this purpose. [ABSTRACT FROM AUTHOR]

The current information regarding the occurrence of steroidal oestrogens and the physiological significance of these compounds in plants is reviewed. Special reference is made to the effects of oestrogens on elongation growth, and results are presented from experiments with Pisum and Phaseolus seedlings. [ABSTRACT FROM AUTHOR]

Zeranol and two Fusarium toxins, α-zearalenol and ß-zearalenol, were confirmed by gaschromatography/mass spectrometry (GC/MS) in bovine bile samples referred to this laboratory for analysis. No evidence of zeranol abuse was found on-farm. Given the recent suggestion that zeranol might arise from the metabolism of these Fusarium toxins, and the finding of zeranol in bovine and ovine urine across the EU, it was concluded that the residues had arisen as a result of natural metabolism. [ABSTRACT FROM AUTHOR]

A temporal study of the biliary elimination of endogenous 19-nortestosterone during two successive pregnancies was made in three cows with cannulated gall bladders. Bile samples were analysed for 17β-19-nortestosterone (β-NT) and the 17α-epimer (α-NT) by using high resolution gas chromatography and mass spectroscopy. No β-NT was detected in any of the samples analysed. However, α-NT was detected from around 120 days of gestation in each of the cows. Peak concentrations were observed in the last week before calving and ranged from 9.5 to 36.7 ng/ml. After parturition, the concentrations of α-NT declined rapidly and were undetectable by seven days after calving, and it was not detected again until after 120 days of gestation. The biliary concentrations of α-NT detected subsequently were similar to those observed in cattle several weeks after an exogenous injection of the synthetic ester β-NT phenylpropionate. [ABSTRACT FROM PUBLISHER]

The article describes a case of secobarbital poisoning in an Amur tiger after the ingestion of potentially contaminated horse meat. It stresses the importance of making sure that chemically euthanased animals are not used for feed and reminds veterinarians of the potential risk of secondary barbiturate poisoning wild, captive and domestic carnivores. It notes that the tiger was treated with intensive nursing care, heating, intravenous fluid therapy, antibiosis and physiotherapy, but was found dead on January 3, 2010.

Whole genome sequencing (WGS) has the potential to report on all types of genetic abnormality, thus converging diagnostic testing on a single methodology. Although WGS at sufficient depth for robust detection of point mutations is still some way from being affordable for diagnostic purposes, low-coverage WGS is already an excellent method for detecting copy number variants ("CNVseq"). We report on a family in which individuals presented with a presumed autosomal recessive syndrome of severe intellectual disability and epilepsy. Array comparative genomic hybridization (CGH) analysis had revealed a homozygous deletion apparently lying within intron 3 of CNTNAP2. Since this was too small for confirmation by FISH, CNVseq was used, refining the extent of this mutation to approximately 76.8 kb, encompassing CNTNAP2 exon 3 (an out-of-frame deletion). To characterize the precise breakpoints and provide a rapid molecular diagnostic test, we resequenced the CNVseq library at medium coverage and performed split read mapping. This yielded information for a multiplex polymerase chain reaction (PCR) assay, used for cascade screening and/or prenatal diagnosis in this family. This example demonstrates a rapid, low-cost approach to converting molecular cytogenetic findings into robust PCR-based tests., (© 2014 Wiley Periodicals, Inc.)

Aims: To study the population pharmacokinetics of piperaquine after co-administration with dihydroartemisinin in uncomplicated malaria., Methods: The disposition of piperaquine was studied in 85 Cambodian patients with uncomplicated falciparum or vivax malaria treated with the piperaquine-dihydroartemisinin coformulation Artekin. All patients were given Artekin orally at 0, 6, 24 and 32 h with a total piperaquine dose of 32-35 mg base kg-1. Adults were given tablets while children received either tablets or a dispersible granule formulation. Patients underwent either intensive (17-19 samples) or sparse (2-5 samples) blood sampling schedules over 35 days and clinical/parasitological follow-up over > 28 days. Piperaquine in plasma was quantified by high performance liquid chromatography., Results: All patients achieved fever clearance within 24 h and parasite clearance within 72 h. The 28-day cure rate was 97% in adults and 98% in children. A covariate-free two-compartment population model with first-order absorption and elimination gave the most robust representation of the plasma concentration-time data in both adults and children. In adults (n = 38), the median (interquartile range) derived pharmacokinetic descriptors CL/F, Vss/F and t1/2,z were 0.9 l h-1 kg-1 (0.79-1.02 l h-1 kg-1), 574 l kg-1(371-711 l kg-1) and 23 days (19-28 days), respectively. In children (n = 47), corresponding values were 1.8 l h-1 kg-1 (1.29-2.3 l h-1 kg-1), 614 l kg-1 (332-1205 l kg-1) and 14 days (10-18 days), respectively., Conclusions: Piperaquine is a highly lipid-soluble drug with a large Vss/F, long t1/2,z and a clearance that is markedly higher in children than in adults.