Quantitative analysis of perfluorinated chemicals in media for in vitro fertilization and related samples

The actual standard in vitro fertilization (IVF) protocol recommends an overnight gamete co-incubation. All of the culture media used for human IVF are supplemented with serum or albumin. In the present study, we determined the concentrations of perfluorinated chemicals (PFCs) in IVF media (IVFM) and related samples by liquid chromatography with tandem mass spectrometry (LC/MS/MS). The results indicated that the concentrations of PFOS and PFOA in the protein source were higher than those in the IVFM samples. Compared with human plasma concentrations of PFCs, PFCs in all of the IVFM samples, such as PFBS, PFHxS and PFOA, were either not detected or present at only trace levels, even when protein source was added. LC/MS/MS could be used to determine PFCs in IVFM samples in future studies of the effects of PFC exposure on intrauterine insemination.     

Spatial distribution and loading amounts of particle sorbed and dissolved perfluorinated compounds in the basin of Tokyo Bay

In this study, we analyzed over 30 types of PFCs, including precursors in both the dissolved phase and particle solid phase, in 50 samples of river water collected from throughout the Tokyo Bay basin. PFCs were detected in suspended solids (SSs) at levels ranging from <0.003-4.4 ng L(-1) (0.11-2470 ng g(-1) dry weight). The concentrations of PFCs in the SS were one to two order(s) of magnitude lower than those of PFCs in the dissolved phase. Relatively high levels of PFCs (total of 35 PFCs) in SS were observed in urbanized areas. The concentration of PFCAs, including PFOA and PFNA, were significantly correlated with the geographic index as artificial area (R(2) of the linear regression curve in a double logarithmic plot: 0.09-0.55). Conversely, PFOS and FOSA were significantly correlated with the arterial traffic area (R(2) in a double logarithmic plot: 0.29-0.55). Those spatial trends were similar to the trends in dissolved PFCs. We estimated the loading amount of PFCs into Tokyo Bay from six main rivers and found that more than 90% of the total PFCs reached Tokyo Bay in the dissolved phase. However, 40.0-83.5% of the long chain PFCAs (C12-C15), were transported as particle sorbed PFCs. Rain runoff events might increase the loading amount of PFCs in SS. Overall, the results presented herein indicate that greater attention should be given to PFCs, especially for longer chain PFCs in SS in addition to dissolved PFCs.     

Seasonal change of PCDDs/PCDFs/DL-PCBs in the water of Ayase River, Japan: pollution sources and their contributions to TEQ

In Japan, Ayase River is one of the most polluted rivers by PCDDs, PCDFs and dioxin-like PCBs, which are referred to as dioxins in this paper. The water samples of the river were collected once per month for a year, and dioxins were analyzed to examine the dioxin sources and their contributions to toxic equivalent (TEQ). The WHO-2006 TEQs ranged from 0.26 to 7.0 pg-TEQ L⁻¹ and the average was 2.7 pg-TEQ L⁻¹; eight of 12 samples exceeded the environmental quality standard in Japan (1.0 pg-TEQ L⁻¹). The TEQ value was high during the irrigation period from May to August. The most part of the dioxins in the river water existed in suspended solids (SS) and it seemed that the river received water with highly-dioxin-contaminated SS in the irrigation period. The homologue profiles of the water samples suggested that the dioxins were influenced by pentachlorophenol (PCP) and chlornitrofen (CNP) formulations which were widely used as herbicides for the paddy fields in Japan. According to TEQ apportionment estimated by using indicative congeners, the TEQ was mainly contributed by PCP. Moreover, it was also shown that the TEQ contributions of PCP and CNP formulations increased along with the increase of the total TEQ and the TEQ contribution was dominated by these herbicides during the irrigation period. Therefore, it was concluded that the herbicides-originated dioxins run off from the paddy fields into the river during the irrigation period and increased the dioxins level in the river water. The result from the principal component analysis was consistent with these conclusions.     

Polychlorinated dibenzo-p-dioxins, dibenzofurans, and dioxin-like polychlorinated biphenyls in rice straw smoke and their origins in Japan

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs) contained in the smoke generated from rice straw burning in post-harvest paddy fields in Japan were analyzed to determine their congener profiles. Both the apportionment of toxic equivalent (TEQ) by using indicative congeners and the comparison of the homolog profiles showed that the PCDDs/PCDFs/DL-PCBs present in the rice-straw smoke were greatly influenced by those present as impurities in pentachlorophenol (PCP) and chlornitrofen (CNP, 4-nitrophenyl-2,4,6-trichlorophenyl ether) formulations that had been widely used as herbicides in paddy fields in Japan. Further, in order to investigate the effects of paddy-field soil on the PCDDs/PCDFs/DL-PCBs present in rice-straw smoke, PCDD/PCDF/DL-PCB homolog profiles of rice straw, rice-straw smoke and paddy-field soil were compared. Rice-straw smoke was generated by burning rice straw on a stainless-steel tray in a laboratory. The results suggested that the herbicides-originated PCDDs/PCDFs/DL-PCBs and the atmospheric PCDDs/PCDFs/DL-PCBs contributed predominantly to the presence of PCDDs/PCDFs/DL-PCBs in the rice-straw smoke while the contribution of PCDDs/PCDFs/DL-PCBs formed during rice straw burning was relatively minimal. The major sources of the PCDDs/PCDFs/DL-PCBs found in the rice-straw smoke were attributed primarily to the paddy-field soil adhered to the rice straw surface and secondarily to the air taken by the rice straw. The principal component analysis supported these conclusions. It is concluded that rice straw burning at paddy fields acts as a driving force in the transfer of PCDDs/PCDFs/DL-PCBs from paddy-field soil to the atmosphere.     

Initial design process of the sustainability science ontology for knowledge-sharing to support co-deliberation

Implementation of the sustainability science (SS) approach is often difficult because of poor communication between experts from different academic fields. We focused on ontology engineering as a method of knowledge structuring that supports the co-deliberation process. However, SS is too broad for a few experts to construct an ontology because SS targets and covers almost all existing research fields from the viewpoint of problem-solving. The N-iteration process is required for completing an SS ontology. In the present paper, we discuss the initial design process for constructing an ontology on SS from the aspect of a knowledge-sharing tool to support co-deliberation. First, we identified the SS ontology by referring to the existing literature. Second, we traced the structuring process of the SS ontology, which is independent of the existing research domain. Third, we compared the SS ontology with existing ontologies or concept structures on SS. Fourth, we assessed the SS ontology produced in the initial process in terms of relevance and coverage and addressed areas for improvement in order to facilitate co-deliberation among researchers from different domains. As a result of developing the SS ontology and applying it to the mapping tool that we developed based on the ontology, we found the following three points: the SS ontology enables us to define concepts relevant to SS without overlapping by distinguishing part-of and attribute-of relationships at the upper level of the ontology; the SS-based mapping tool successfully represents the potential countermeasures required by the targeted problem for all scientific fields except experimental engineering; however, the SS ontology requires further improvement in order to represent the conceptual linkage arising from compound and secondary problems and the fulfillment of classes at the lower hierarchy of Shortage problem, and requires slots for the entire hierarchy. In addition, based on the discussion of the areas for improvement, we found that missing slots and classes should be added in the process in which we use or improve tools corresponding to a variety of requirements for supporting co-deliberation. In this way, we are able to propose an incremental process for constructing the SS ontology from the aspect of a knowledge-sharing tool to support co-deliberation.     

Purification and characterization of extracellular poly(3-hydroxybutyrate) depolymerases

Five extracellular PHB depolymerases of bacteria isolated from various sources were purified to electrophoretic homogeneity and compared with known extracellular PHB depolymerase fromAlcaligenes faecalis T1. The molecular mass of these enzymes were all around 40–50 kDa. Nonionic detergent, diisopropylfluorophosphate and dithiothreitol inhibited the PHB depolymerase activity of all these enzymes. Trypsin abolished PHB depolymerase activity, but not theD-3-hydroxybutyric acid dimer hydrolase activity of all the enzymes. These results showed that the basic properties of these PHB depolymerases resemble those of theA. faecalis T1 enzyme. Analysis ofN-terminal amino acid sequence of the purified enzymes revealed that these enzymes includingA. faecalis T1 enzyme fall into three groups.     

Respiratory tract retention of inhaled air pollutants: Report 1 : Mercury absorption by inhaling through the nose and expiring through the mouth at various concentrations

To study atmospheric mercury absorption in human respiratory passage-ways, mercury in expired air was measured in three different states of breathing: steady breathing, deep breathing and breath held after inspiration.In this study, air containing mercury was inhaled through the nose and expired through the mouth. The concentration of mercury in the exhaled air was determined by the technique of gold-amalgam trapping, heat vaporization, and flameless atomic absorption measurement.The subjects were 13 male adults, aged 25–62 years, and 38 cases were observed. Four different concentrations of mercury, 1–3, 4–6, 10–11, and 20–30 μg/m³ were used, and absorption for each was determined. When the concentration was 1–3 μg/m₃, the absorption was 74–92%, the average being 82.5%. At concentrations of 4–6, 10–11, and 20–30 μg/m₃, the absorption was 76.6–100%, 75.5–99.2%, and 79.9–95.9% respectively, and the average was 88.8%, 85.2%, and 87.7% respectively.A slightly higher rate of mercury absorption was observed in deep breathing than in steady breathing, and when expiration was suppressed for some time after inspiration, the rate increased remarkably to 97.4–99.7%. Prolonged retention of inhaled air containing mercury in the respiratory tract is believed to have caused the increased absorption.     

Fire effects on stable isotopes in a Sierran forested watershed

This study tested the hypothesis that stable C and N isotope values in surface soil and litter would be increased by fire due to volatilization of lighter isotopes. The hypothesis was tested by: (1) performing experimental laboratory burns of organic and mineral soil materials from a watershed at combinations of temperature ranging 100 to 600 degrees C and duration ranging from 1 to 60 min; (2) testing field samples of upland soils before, shortly after, and 1 yr following a wildfire in the same watershed; and (3) testing field soil samples from a down-gradient ash/sediment depositional area in a riparian zone following a runoff event after the wildfire. Muffle furnace results indicated the most effective temperature range for using stable isotopes for tracing fire impacts is 200 to 400 degrees C because lower burn temperatures may not produce strong isotopic shifts, and at temperatures>or=600 degrees C, N and C content of residual material is too low. Analyses of field soil samples were inconclusive: there was a slightly significant effect of the wildfire on delta15N values in upland watershed analyses 1 yr postburn, while riparian zone analyses results indicated that delta13C values significantly decreased approximately 0.71 per thousand over a 9 mo post-fire period (p=0.015), and ash/sediment layer delta13C values were approximately 0.65 per thousand higher than those in the A horizon. The lack of field confirmation may have been due to overall wildfire burn temperatures being <200 degrees C and/or microbial recovery and vegetative growth in the field. Thus, the muffle furnace experiment supported the hypothesis, but it is as yet unconfirmed by actual wildfire field data.     

Effect of Tinospora cordifolia on the reduction of ultraviolet radiation‐induced cytotoxicity and DNA damage in PC12 cells

The safety of Tinospora cordifolia and its potential to protect against ultraviolet radiation‐induced cytotoxicity and DNA damage in PC12 cells were investigated. To evaluate the safety of T. cordifolia, cell viability and agarose gel electrophoresis were carried out using PC12 cells treated with 0 to 100 μg mL^?1 of methanol extract of T. cordifolia. T. cordifolia extracts did not show cytotoxicity ranging 0 to 100 μg mL^?1. In addition, T. cordifolia extracts significantly increased cell viability at 1 ng, 10 ng and 1 μg mL^?1 concentrations in serum‐deprived medium compared to control. To confirm the protective role against UV‐induced damage, PC12 cells alone or in the presence of 10 ng, 100 ng, or 1 μg mL^?1 of T. cordifolia extract were exposed to 250, 270 and 290 nm of UV radiation, which corresponded to doses of 120, 150 and 300 mJ cm^?2, respectively. Treatment with T. cordifolia extracts significantly increased the cell survival rate irradiated at 290 nm. In addition, T. cordifolia extracts significantly reduced cyclobutane pyrimidine dimer formation induced by UV irradiation at all wavelengths. In conclusion, T. cordifolia is not toxic and safe for cells. Our findings can support its application as phototherapy in the medical sector.     

TEMPO-Mediated Oxidation of Norway Spruce and Eucalyptus Pulps: Preparation and Characterization of Nanofibers and Nanofiber Dispersions

This study deals with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation of cellulose. Softwood and hardwood pulp fibers were suspended in water and oxidized to various extents at pH 10 and 22 °C using sodium hypochlorite in the presence of TEMPO radical and sodium bromide. This reaction system is known to be the most efficient one for the introduction of both surface carboxyl and aldehyde groups. Important relationships between formation of these functional groups and the fibrillation yield, light transmittance of the water dispersions and degree of polymerization of the oxidized softwood and hardwood pulps were established in the present study. A birefringence test confirmed the presence of nanofibers which according to atomic force microscopy analyses had diameters in the 1.6–3.8 nm range.