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Perfluorinated surfactants and repellents are synthetic substances that have found numerous industrial and customer applications. Due to their persistence, at least two groups of these substances—perfluorinated carboxylic acids (PFCAs) and perfluorinated sulfonic acids (PFSAs)—are diffused widely in the environment. It is hypothesized that the Tibetan Plateau, is one of few unique places on the Earth, due to its topography, specifically the vast space and high elevation above sea level, geographic location, climate, high solar radiation, lack of industry, little urbanization and general lack of significant direct sources of pollution. There it is believed possible to gain an insight into atmospheric fate (possible photochemical degradation of higher molecular mass and formation of lower molecular mass PFCAs and PFSAs) of PFASs under un-disturbed environmental conditions. Ultratrace analytical method for PFCAs and PFSAs and use of transportation and field blanks, laboratory blanks and isotopically labelled surrogates for recovery control has allowed the determination of nine perfluorinated carboxylic acids and six perfluorinated sulfonic acids at ultra-trace levels in water based samples from the alpine dimension regions of the Tibetan Plateau, the eastern slope of Minya Konka peak at the eastern edge of the Tibetan Plateau, and also from the city of Chengdu from the lowland of the Sichuan Province in China. The specific compositional pattern of PFCAs and PFSAs and low levels of pollution with those compounds were observed in the central region of the Tibetan Plateau and in the region adjacent to the peaks of Minya Konka in the Eastern Tibetan Plateau. The fingerprint of the compositional pattern of PFCAs and PFSAs in water samples in the central region of the Tibetan Plateau and in the alpine region adjacent to the peaks of Minya Konka in the Eastern Tibetan Plateau may be explained by the result of photochemical degradation with dealkylation of longer chain compounds and formation of shorter chain compounds, which are more resistant to photochemical degradation. [ABSTRACT FROM PUBLISHER]

The article provides a summary of the background and past activities of the E6 Discussion Group established under the International Pharmaceutical Regulators Forum. Topics discusses include the establishment of the Regulators Forum to create a regulator-only environment, the development of a statement on general principles for the training and education of Good Clinical Practice (GCP) inspectors which will serve as a reference to regulatory agencies.

Per- and poly-fluoroalkyl substances (PFASs) have been widely detected in the hydrosphere. The knowledge on the distribution and composition patterns of PFAS analogues with different chain length significantly contribute to their source analysis. In the present study, a regional scale investigation of PFASs in surface river waters and adjacent ground waters was carried out in two cities of China with potential contamination, Tianjin and Weifang. A total of 31 water samples were collected, and 20 PFASs therein were measured by a high-performance liquid chromatograph–tandem mass spectrometer (HPLC–MS/MS). The possible sources of PFASs in the aquatic environment were assessed primarily by concentration patterns as well as hierarchical cluster analysis. In all 4 rivers investigated in the two cities, perfluoroalkyl carboxylic acids (PFCAs) were the dominant compounds contributing over 70% of the PFASs detected. Perfluorooctanoic acid (PFOA) was the dominant PFCA with a concentration range of 8.58–20.3 ng/L in Tianjin and 6.37–25.9 ng/L in Weifang, respectively. On the average, the highest concentration was observed in samples from Dagu Drainage Canal (Dagu) in Tianjin and those short-chain PFASs (C4–C6) was detected with a comparable level of the longer-chain PFASs (>C6). Specifically, perfluorobutanoic acid (PFBA) was dominant in the short-chain analogues. This indicates that a remarkably increasing input of short-chain PFASs might be related to wastewater treatment plant effluent or industrial discharges, which could be possibly due to the switch of manufacturing to short-chain products. In Weifang, precipitation and subsequent surface runoff as non-point sources could be significant inputs of PFASs into surface water while groundwater was possibly subjected to severe point sources with ∑PFASs concentration up to ~100 ng/L. The inconsistent distribution patterns in groundwater suggest complicated pathways of contamination. [ABSTRACT FROM AUTHOR]

Novel per- and polyfluoroalkyl substances (PFASs) have become a key issue in global environmental studies. Although several novel PFASs have been discovered in atmospheric particulate matter through nontarget analysis, information on the environmental occurrence of novel PFASs in atmospheric gaseous phases and conventional sampling techniques is somewhat deficient. Therefore, this Article describes a new type of air sampler, the cryogenic air sampler (CAS), which was used to collect all atmospheric components simultaneously. Nontarget analysis then was performed through PFASs homologue analysis. A total of 117 PFAS homologues (38 classes) were discovered, 48 of which (13 classes) were identified with confidence Level 4 or above. Eleven chlorinated perfluoropolyether alcohols (3 classes) and four chlorinated perfluoropolyether carboxylic acids (2 classes) have been reported for the first time in this Article. This Article is also the first report of 12 hydrosubstituted perfluoroalkyl carboxylates (H-PFCAs) in the atmosphere. H-PFCAs and chlorinated perfluoropolyether carboxylic acids were mainly distributed in the particular phase. These results are evidence that novel chlorinated polyether PFASs should be the focus of future study.

In this study, we evaluated the efficacy of a novel minipig strain, the Microminipig (MMPig), as an animal model for studying the pharmacokinetics of a mixture of 10 perfluoroalkyl acids (PFAAs). After a single oral dose was given, we found that the blood depuration of PFAAs (blood t1/2), which we calculated using first-order elimination curves, ranged from 1.6 to 86.6 days. Among the five body compartments analyzed, the liver was the greatest site of accumulation of perfluorooctanesulfonate and longer chain perfluorinated carboxylates such as perfluorodecanoic acid, perfluoroundecanoic acid and perfluorododecanoic acid. We observed an increasing accumulation trend of perfluorinated carboxylates in the organs associated with the fluorinated carbon chain length. The perfluorononanoic acid burden was the highest among the treated compounds 21 days after a single exposure, as 29% of the given perfluorononanoic acid dose was accumulated in the tissues. The persistence of PFAAs in edible pig tissues even after 21 days post-exposure raises concerns about the safety of swine products. This was the first study to use MMPigs to elucidate the pharmacokinetics of a group of environmental pollutants. We found that MMPigs could be excellent experimental animals for toxicological studies due to their easy handling, cost efficacy for target compounds and ease of waste treatment., (Copyright © 2015 John Wiley & Sons, Ltd.)

Water samples collected along the Japanese coast and in the open Pacific Ocean in 2010, 2011, and 2012 were analyzed for perfluoroalkyl substances (PFASs) to evaluate the effect of Great East Japan Earthquake (EQ 3.11), which occurred on March 11, 2011, on the dispersion of chemical pollutants. Ultratrace analysis of PFASs in water, a super computer simulation, and an inventory analysis from industrial records revealed the sources and dynamics of PFASs during the EQ 3.11 disaster. In this respect, EQ 3.11 destroyed solid infrastructure on land, and within minutes, PFASs stocked therein were released into the open environment. The historically significant tsunami backwash swept them away from their origin to the coastal water within several hours. It was estimated that from 0.8 to 1.0 tons of perfluorooctanesulfonate (PFOS) and 4.8 to 5.1 tons of PFOA were discharged into the coastal waters after EQ 3.11 and the tsunami that followed. The reconstruction of EQ 3.11 also traced the influence of this pollution in open ocean water until March 2012, and a statistical and finger printing analysis revealed that there were different distribution mechanisms in coastal regions than in the open ocean for PFOS, other shorter chain perfluorinated sulfonic acids and perfluorinated carboxylic acids.

Background/aims: In this pilot study, a new breath test system for gastric emptying study has been proposed., Methodology: The system involves 13C-uracil as a novel tracer and the Wagner-Nelson method for analyzing breath data., Results: In three healthy volunteers, the new breath system allowed quantification of gastric emptying profiles as accurately as the scintigraphic technique., Conclusions: Further validation studies with a lager sample size are needed.

Purpose of Review: To summarize recent findings on vitamin C status and assess the requirement and optimal dose of supplementation in surgical patients., Recent Findings: Blood vitamin C concentration falls after uncomplicated surgery and further decreases in surgical intensive care unit patients. The decline may be owing to increased demand caused by increased oxidative stress. To normalize plasma vitamin C concentration, much higher doses than the recommended daily allowance or doses recommended in parenteral nutrition guidelines are needed in these patients. In uncomplicated surgical patients, more than 500 mg/day of vitamin C may be required, with much higher doses in surgical intensive care unit patients. In uncomplicated gastrointestinal surgery, continuous parenteral administration of 500 mg/day of vitamin C reduced postoperative oxidative stress as manifested by reduced urinary excretion of isoprostane. In some studies, postoperative atrial fibrillation was prevented after cardiac surgery by perioperative vitamin C supplementation. In critically ill patients, some prospective randomized controlled trials support parenteral supplementation of high doses of vitamin C, E and trace elements., Summary: Vitamin C requirement is increased in surgical patients, and the potential advantage of supplementation is to increase the plasma and tissue levels of vitamin C and thereby reduce oxidative stress. Although some clinical benefits of high-dose vitamin C supplementation have been shown in the critically ill, the optimal dose for supplementation and the clinical benefits remain to be investigated in surgical patients.

The authors previously demonstrated that intracytoplasmic inclusion bodies (1-3 microm) in the mouse locus coeruleus under light and electron microscopy are characteristically stained using the Holmes modified method. We reported that one inclusion body existed in almost all neurons of the locus coeruleus. The present study examined whether similar inclusion bodies are present in the Syrian hamster (weight, about 60 g). Paraffin sections stained with the modified Holmes' method dis played numerous small inclusion bodies in the cytoplasm of cells in the locus coeruleus. Epon sections (1 microm thick) stained using toluidine blue were observed under light microscopy, and numerous small inclusion bodies were again observed. Under electron microscopy observation, inclusion bodies (<1 microm in diameter) predominantly comprised small granular materials, similar to those described by previous investigators. Although inclusion bodies were devoid of a limiting membrane, the relation ship to cytoplasmic organelles was unclear. However, free and polyribosomes were occasionally noted in close proximity to inclusion bodies. Inclusion bodies may thus be formed from ribosomes. Intracytoplasmic inclusion bodies in the hamster locus coeruleus differed in appearance compared with inclusion bodies in the mouse locus coeruleus.