Publications by authors named "Sawin V"

Mathematical modeling studies are frequently conducted to guide policy in global health. However, the contribution of mathematical modeling studies to World Health Organization (WHO) guideline recommendations, and the quality of evidence contributed by these studies remains unknown. We conducted a systematic review of the WHO Guidelines Review Committee database to identify guideline recommendations that included evidence from mathematical modeling studies since inception of the Guidelines Review Committee on 1 December, 2007.

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Background: In the face of an unclear causal association between Zika virus in utero exposure and congenital abnormalities and urgent demand for guidance, the World Health Organization (WHO) had to produce timely and trustworthy guidelines during the 2016 Public Health Emergency of International Concern (PHEIC).

Methods: This is a cross-sectional evaluation of WHO emergency guidelines produced during the Zika virus disease PHEIC from 1 February to 18 November 2016. We assessed adherence to WHO publication requirements and the reporting of guideline development processes associated with trustworthiness.

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Background: The production of high-quality guidelines in response to public health emergencies poses challenges for the World Health Organization (WHO). The urgent need for guidance and the paucity of structured scientific data on emerging diseases hinder the formulation of evidence-informed recommendations using standard methods and procedures.

Objectives: In the context of the response to recent public health emergencies, this project aimed to describe the information products produced by WHO and assess the quality and trustworthiness of a subset of these products classified as guidelines.

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Objectives: We assessed citation of prior research over time and the association of citation with the agreement of results between the trial being reported and the prior trial.

Study Design And Setting: Groups of pharmacologic trials in cardiovascular disease were created using meta-analyses, and we assessed citation within these groups. We calculated the proportion of prior trials cited, the proportion of study participants captured in citations, and agreement of results between citing and cited trials.

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Exposure to the mutagen triethylenemelamine on rat bone marrow, blood, and testis was studied using flow cytometry of DAPI-stained nuclei. Increased coefficients of variation (CVs) of the G1 peaks were observed in bone marrow and blood after both 1 d and 5 d exposures. After 5 d exposure and 7 d recovery both tissues had recovered, in some cases to significantly lower CVs.

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The effects of short-term (24 h) exposure to triethylenemelamine on cellular DNA in five tissues (bone marrow, spleen, kidney, large intestine, and testis) of the rat were studied using flow cytometry. Mean coefficients of variation of the G1 peaks were increased in both the low and high dosage groups relative to controls. Bone marrow exhibited the highest degree of effect, possibly due to the rapid rate of cell division in that tissue, and spleen was next highest.

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The objective of this study was to determine the kinetics of absorption, distribution, and elimination of DBCP after intravenous (iv) administration in plasma, and after oral administration in water or corn oil, to conscious, fed, male Fischer 344 rats. Rats were prepared with an external jugular vein cannula and were dosed with 0.1, 1, or 10 mg/kg DBCP into the penile sinus or orally as a solution in water or in corn oil (1 mg/kg only).

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The major urinary metabolite of 14C-epichlorohydrin, after oral administration to rats, was identified previously (Gingell et al. 1985) to be N-acetyl-S-(3-chloro-2-hydroxypropyl)-L-cysteine (ACPC) at 36% of the administered dose. In a similar study reported here, 1,2-dibromo-3-chloropropane (DBCP) was metabolized to at least 20 radioactive urinary metabolites.

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A comprehensive disposition and metabolism study of epichlorohydrin (ECH) has not been previously reported. In this study, male Fischer 344 rats were dosed (6 mg/kg) orally with [2-14C]ECH (98% radiochemically pure) as an aqueous solution and killed after 3 days. Approximately 38% of the radioactive dose was exhaled as CO2, 50% was excreted as metabolites in the urine, and 3% was present in the feces.

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The available results for tests on over 200 surfactants in nine short-term genotoxicity assay systems were reviewed. These tests included the Salmonella/microsome mutation assay, bacterial DNA repair tests, mitotic recombination in Saccharomyces cerevisiae, the mouse lymphoma cell-mutation assay, unscheduled DNA synthesis and sister chromatid exchange assays in mammalian cells, mammalian chromosome damage tests in vitro and in vivo, the dominant lethal test in rodents, and mammalian cell-transformation tests. The collected data cover all four major classes of surfactants: anionic, cationic, nonionic and amphoteric.

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Metaphase chromosomes from the Chinese hamster cell line M3-1 were separated by means of a flow sorter. Two chromosome fractions were used for this study: A, which consisted of 95% pure chromosome no. 1, and B, which was 90% pure chromosome no.

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A procedure is described for quinacrine banding of radiolabeled metaphase chromosomes for autoradiography. The chromosomes can be labeled either in vivo or by in situ hybridization. The banding procedure involves treating the slides with RNase and formamide and staining in quinacrine.

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