Effects of seven chemicals on DNA damage in the rat urinary bladder: a comet assay study.

PubMed

Wada, Kunio; Yoshida, Toshinori; Takahashi, Naofumi; Matsumoto, Kyomu

2014-07-15

The in vivo comet assay has been used for the evaluation of DNA damage and repair in various tissues of rodents. However, it can give false-positive results due to non-specific DNA damage associated with cell death. In this study, we examined whether the in vivo comet assay can distinguish between genotoxic and non-genotoxic DNA damage in urinary bladder cells, by using the following seven chemicals related to urinary bladder carcinogenesis in rodents: N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN), glycidol, 2,2-bis(bromomethyl)-1,3-propanediol (BMP), 2-nitroanisole (2-NA), benzyl isothiocyanate (BITC), uracil, and melamine. BBN, glycidol, BMP, and 2-NA are known to be Ames test-positive and they are expected to produce DNA damage in the absence of cytotoxicity. BITC, uracil, and melamine are Ames test-negative with metabolic activation but have the potential to induce non-specific DNA damage due to cytotoxicity. The test chemicals were administered orally to male Sprague-Dawley rats (five per group) for each of two consecutive days. Urinary bladders were sampled 3h after the second administration and urothelial cells were analyzed by the comet assay and subjected to histopathological examination to evaluate cytotoxicity. In the urinary bladders of rats treated with BBN, glycidol, and BMP, DNA damage was detected. In contrast, 2-NA induced neither DNA damage nor cytotoxicity. The non-genotoxic chemicals (BITC, uracil, and melamine) did not induce DNA damage in the urinary bladders under conditions where some histopathological changes were observed. The results indicate that the comet assay could distinguish between genotoxic and non-genotoxic chemicals and that no false-positive responses were obtained. Copyright © 2014 Elsevier B.V. All rights reserved.

Photomixotrophic chemical production in cyanobacteria.

PubMed

Matson, Morgan M; Atsumi, Shota

2018-04-01

The current global dependence on fossil fuels for both energy and chemical production has spurred concerns regarding long-term resource security and environmental detriments resulting from increased CO 2 levels. Through the installation of exogenous metabolic pathways, engineered cyanobacteria strains can directly fix CO 2 into industrially relevant chemicals currently produced from petroleum. This review highlights some of the studies that have successfully implemented photomixotrophic conditions to increase cyanobacterial chemical production. Supplementation with fixed carbon sources provides additional carbon building blocks and energy to enhance production and occasionally aid in growth. Photomixotrophic production has increased titers up to 5-fold over traditional autotrophic conditions, demonstrating promising applications for future commercialization. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Clinical Test of Nano gold Cosmetic for Recovering Skin Damage Due to Chemicals: Special Case

NASA Astrophysics Data System (ADS)

Taufikurohmah, T.; Wardana, A. P.; Tjahjani, S.; Sanjaya, I. G. M.; Baktir, A.; Syahrani, A.

2018-01-01

Manufacturing of Nano gold cosmetics was done at PT. Gizi Indonesia. Clinical trials to cosmetics data supported that cosmetics are able to treat skin health which has been reported partially. For special cases, the recovery process of facial skin damage should also receive attention including cases of facial skin damage caused by chemicals such as phenol, HCl, aqua regia or other harsh chemicals. The problem determined whether the Nano gold is able to recover skin damage due to the harsh chemicals. This clinical trial data on the forms of early skin damage caused by phenol was delivered in the forms of facial photos patients. The recovery progress of facial skin condition was obtained every week for two months. The data included the forms of widespread wounds during the recovery process. This statement supported by anova statistical analysis of the widespread wound changing every week for 8 times. The conclusion is skin damage due to Phenol impregnation can be recovered with the use of Nano gold cosmetics for 8 weeks. This results support the manufacturing of Nano gold cosmetics for the needs of society. It also suggest that Nano gold material can be used for medicine manufacturing in the future.

Mapping Global Flows of Chemicals: From Fossil Fuel Feedstocks to Chemical Products.

PubMed

Levi, Peter G; Cullen, Jonathan M

2018-02-20

Chemical products are ubiquitous in modern society. The chemical sector is the largest industrial energy consumer and the third largest industrial emitter of carbon dioxide. The current portfolio of mitigation options for the chemical sector emphasizes upstream "supply side" solutions, whereas downstream mitigation options, such as material efficiency, are given comparatively short shrift. Key reasons for this are the scarcity of data on the sector's material flows, and the highly intertwined nature of its complex supply chains. We provide the most up to date, comprehensive and transparent data set available publicly, on virgin production routes in the chemical sector: from fossil fuel feedstocks to chemical products. We map global mass flows for the year 2013 through a complex network of transformation processes, and by taking account of secondary reactants and by-products, we maintain a full mass balance throughout. The resulting data set partially addresses the dearth of publicly available information on the chemical sector's supply chain, and can be used to prioritise downstream mitigation options.

Advancing Consumer Product Composition and Chemical ...

EPA Pesticide Factsheets

This presentation describes EPA efforts to collect, model, and measure publically available consumer product data for use in exposure assessment. The development of the ORD Chemicals and Products database will be described, as will machine-learning based models for predicting chemical function. Finally, the talk describes new mass spectrometry-based methods for measuring chemicals in formulation and articles. This presentation is an invited talk to the ICCA-LRI workshop "Fit-For-Purpose Exposure Assessments For Risk-Based Decision Making". The talk will share EPA efforts to characterize the components of consumer products for use in exposure assessment with the international exposure science community.

Production of thymine glycols in DNA by radiation and chemical carcinogens as detected by a monoclonal antibody.

PubMed Central

Leadon, S. A.

1987-01-01

In order to understand the role in carcinogenesis of damage indirectly induced by chemical carcinogens, it is important to identify the primary DNA lesions. We have measured the formation and repair of one type of DNA modification, 5,6-dihydroxydihydrothymine (thymine glycol), following exposure of cultured human cells to the carcinogens N-hydroxy-2-naphthylamine or benzo(a)pyrene. The efficiency of production of thymine glycols in DNA by these carcinogens was compared to that by ionizing radiation and ultraviolet light. Thymine glycols were detected using a monoclonal antibody against this product in a sensitive immunoassay. We found that thymine glycols were produced in DNA in a dose dependent manner after exposure to the carcinogens and that their production was reduced if either catalase or superoxide dismutase or both were present at the time of treatment. The efficiency of thymine glycol production following exposure to the chemical carcinogens was greater than that following equi-toxic doses of radiation. Thymine glycols were efficiently removed from the DNA of human cells following treatment with either the chemical carcinogens, ionizing radiation or ultraviolet light. PMID:3477281

Ultraviolet Shadowing of RNA Can Cause Significant Chemical Damage in Seconds

PubMed Central

Kladwang, Wipapat; Hum, Justine; Das, Rhiju

2012-01-01

Chemical purity of RNA samples is important for high-precision studies of RNA folding and catalytic behavior, but photodamage accrued during ultraviolet (UV) shadowing steps of sample preparation can reduce this purity. Here, we report the quantitation of UV-induced damage by using reverse transcription and single-nucleotide-resolution capillary electrophoresis. We found photolesions in a dozen natural and artificial RNAs; across multiple sequence contexts, dominantly at but not limited to pyrimidine doublets; and from multiple lamps recommended for UV shadowing. Irradiation time-courses revealed detectable damage within a few seconds of exposure for 254 nm lamps held at a distance of 5 to 10 cm from 0.5-mm thickness gels. Under these conditions, 200-nucleotide RNAs subjected to 20 seconds of UV shadowing incurred damage to 16-27% of molecules; and, due to a ‘skin effect’, the molecule-by-molecule distribution of lesions gave 4-fold higher variance than a Poisson distribution. Thicker gels, longer wavelength lamps, and shorter exposure times reduced but did not eliminate damage. These results suggest that RNA biophysical studies should report precautions taken to avoid artifactual heterogeneity from UV shadowing. PMID:22816040

Methods for evaluating the effects of environmental chemicals on human sperm production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wyrobek, A.J.

1982-04-20

Sperm tests provide a direct and effective way of identifying chemical agents that induce spermatogenic damage in man. Four human sperm tests are available: sperm count, motility, morphology (seminal cytology), and the Y-body test. These sperm tests have numerous advantages over other approaches for assessing spermatogenic damage, and they have already been used to assess the effects of at least 85 different occupational, envionmental, and drug-related chemical exposures. When carefully controlled, seminal cytology appears to be statistically more sensitive than the other human sperm tests and should be considered an integral part of semen analysis when assessing induced spermatogenic damage.

Chemical Waste and Allied Products.

PubMed

Hung, Yung-Tse; Aziz, Hamidi Abdul; Ramli, Siti Fatihah; Yeh, Ruth Yu-Li; Liu, Lian-Huey; Huhnke, Christopher Robert

2016-10-01

This review of literature published in 2015 focuses on waste related to chemical and allied products. The topics cover the waste management, physicochemical treatment, aerobic granular, aerobic waste treatment, anaerobic granular, anaerobic waste treatment, chemical waste, chemical wastewater, fertilizer waste, fertilizer wastewater, pesticide wastewater, pharmaceutical wastewater, ozonation. cosmetics waste, groundwater remediation, nutrient removal, nitrification denitrification, membrane biological reactor, and pesticide waste.

Pea weevil damage and chemical characteristics of pea cultivars determining their resistance to Bruchus pisorum L.

PubMed

Nikolova, I

2016-04-01

Bruchus pisorum (L.) is one of the most intractable pest problems of cultivated pea in Europe. Development of resistant cultivars is very important to environmental protection and would solve this problem to a great extent. Therefore, the resistance of five spring pea cultivars was studied to B. pisorum: Glyans, Modus; Kamerton and Svit and Pleven 4 based on the weevil damage and chemical composition of seeds. The seeds were classified as three types: healthy seeds (type one), damaged seeds with parasitoid emergence holes (type two) and damaged seeds with bruchid emergence holes (type three). From visibly damaged pea seeds by pea weevil B. pisorum was isolated the parasitoid Triaspis thoracica Curtis (Hymenoptera, Braconidae). Modus, followed by Glyans was outlined as resistant cultivars against the pea weevil. They had the lowest total damaged seed degree, loss in weight of damaged seeds (type two and type three) and values of susceptibility coefficients. A strong negative relationship (r = -0.838) between the weight of type one seeds and the proportion of type three seeds was found. Cultivars with lower protein and phosphorus (P) content had a lower level of damage. The crude protein, crude fiber and P content in damaged seeds significantly or no significantly were increased as compared with the healthy seeds due to weevil damage. The P content had the highest significant influence on pea weevil infestation. Use of chemical markers for resistance to the creation of new pea cultivars can be effective method for defense and control against B. pisorum.

Mechanisms of neurotoxicity induced in the developing brain of mice and rats by DNA-damaging chemicals.

PubMed

Doi, Kunio

2011-01-01

It is not widely known how the developing brain responds to extrinsic damage, although the developing brain is considered to be sensitive to diverse environmental factors including DNA-damaging agents. This paper reviews the mechanisms of neurotoxicity induced in the developing brain of mice and rats by six chemicals (ethylnitrosourea, hydroxyurea, 5-azacytidine, cytosine arabinoside, 6-mercaptopurine and etoposide), which cause DNA damage in different ways, especially from the viewpoints of apoptosis and cell cycle arrest in neural progenitor cells. In addition, this paper also reviews the repair process following damage in the developing brain.

Estimating Damage Cost of Net Primary Production due to Climate Change and Ozone(O3) Effect

NASA Astrophysics Data System (ADS)

Park, J. H.; Lee, D. K.; Park, C.; Sung, S.; Kim, H. G.; Mo, Y.; Kim, S.; Kil, S.

2016-12-01

Forests are absorbing and storing carbon dioxide (CO2) through photosynthesis. The forests are not only preventing global warming but also influencing temperature, precipitation and humidity (Costanza et al., 1997; de Groot et al., 2002). Also the forests are recognized as a carbon sink internationally (van Kooten, 2009). The Korean Government supports the economic activity such as carbon offset projects in accordance with 'ACT ON THE MANAGEMENT AND IMPROVEMENT OF CARBON SINK' Article27 (Korea Forest Service, 2013) and aims to make a policy which improves the CO2 capacity of forest for Paris Agreement discussed in UNFCCC COP21, December 2015 (Korea Forest Service, 2015). However, the social-economic activities make to increase aerosols as well as greenhouse gases significantly since the industrial revolution, as a result, the chemical composition of the atmosphere has changed significantly. According to the resent studies, not only CO2 but atmospheric chemistries such as ozone (O3), aerosol and black carbon can be an important factor causing climate change (Hansen et al., 2007; IPCC, 2007). In the past, acid rain affected on forest, but in these days, O3, nitrogen oxide (NOX) and sulfur oxide (SOX) are the most threatening factors on forest ecosystem (Lee et al, 2011). In particular, O3accounts for most of the photochemical products and causes a direct significant impact or damage on the plant because of high toxicity (Han et al., 2006). The research questions of this study are "How does O3 effects on forest productivity in the present and future? " What is the damage cost by the O3 effect in the future? In this study, we developed a statistical model using the parameters which effect on the forest productivity. We estimated the forest productivity using on the derived model in the present and future on a SSP scenarios. Lastly, we evaluated the economic effect or damage cost of O3effect by introducing the concept of climate insurance. The average forest

Bee products prevent agrichemical-induced oxidative damage in fish.

PubMed

Ferreira, Daiane; Rocha, Helio Carlos; Kreutz, Luiz Carlos; Loro, Vania Lucia; Marqueze, Alessandra; Koakoski, Gessi; da Rosa, João Gabriel Santos; Gusso, Darlan; Oliveira, Thiago Acosta; de Abreu, Murilo Sander; Barcellos, Leonardo José Gil

2013-01-01

In southern South America and other parts of the world, aquaculture is an activity that complements agriculture. Small amounts of agrichemicals can reach aquaculture ponds, which results in numerous problems caused by oxidative stress in non-target organisms. Substances that can prevent or reverse agrichemical-induced oxidative damage may be used to combat these effects. This study includes four experiments. In each experiment, 96 mixed-sex, 6-month-old Rhamdia quelen (118±15 g) were distributed into eight experimental groups: a control group that was not exposed to contaminated water, three groups that were exposed to various concentrations of bee products, three groups that were exposed to various concentrations of bee products plus tebuconazole (TEB; Folicur 200 CE™) and a group that was exposed to 0.88 mg L(-1) of TEB alone (corresponding to 16.6% of the 96-h LC50). We show that waterborne bee products, including royal jelly (RJ), honey (H), bee pollen (BP) and propolis (P), reversed the oxidative damage caused by exposure to TEB. These effects were likely caused by the high polyphenol contents of these bee-derived compounds. The most likely mechanism of action for the protective effects of bee products against tissue oxidation and the resultant damage is that the enzymatic activities of superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) are increased.

Suspect Screening Analysis of Chemicals in Consumer Products.

PubMed

Phillips, Katherine A; Yau, Alice; Favela, Kristin A; Isaacs, Kristin K; McEachran, Andrew; Grulke, Christopher; Richard, Ann M; Williams, Antony J; Sobus, Jon R; Thomas, Russell S; Wambaugh, John F

2018-03-06

A two-dimensional gas chromatography-time-of-flight/mass spectrometry (GC×GC-TOF/MS) suspect screening analysis method was used to rapidly characterize chemicals in 100 consumer products-which included formulations (e.g., shampoos, paints), articles (e.g., upholsteries, shower curtains), and foods (cereals)-and therefore supports broader efforts to prioritize chemicals based on potential human health risks. Analyses yielded 4270 unique chemical signatures across the products, with 1602 signatures tentatively identified using the National Institute of Standards and Technology 2008 spectral database. Chemical standards confirmed the presence of 119 compounds. Of the 1602 tentatively identified chemicals, 1404 were not present in a public database of known consumer product chemicals. Reported data and model predictions of chemical functional use were applied to evaluate the tentative chemical identifications. Estimated chemical concentrations were compared to manufacturer-reported values and other measured data. Chemical presence and concentration data can now be used to improve estimates of chemical exposure, and refine estimates of risk posed to human health and the environment.

'Nothing of chemistry disappears in biology': the Top 30 damage-prone endogenous metabolites.

PubMed

Lerma-Ortiz, Claudia; Jeffryes, James G; Cooper, Arthur J L; Niehaus, Thomas D; Thamm, Antje M K; Frelin, Océane; Aunins, Thomas; Fiehn, Oliver; de Crécy-Lagard, Valérie; Henry, Christopher S; Hanson, Andrew D

2016-06-15

Many common metabolites are intrinsically unstable and reactive, and hence prone to chemical (i.e. non-enzymatic) damage in vivo Although this fact is widely recognized, the purely chemical side-reactions of metabolic intermediates can be surprisingly hard to track down in the literature and are often treated in an unprioritized case-by-case way. Moreover, spontaneous chemical side-reactions tend to be overshadowed today by side-reactions mediated by promiscuous ('sloppy') enzymes even though chemical damage to metabolites may be even more prevalent than damage from enzyme sloppiness, has similar outcomes, and is held in check by similar biochemical repair or pre-emption mechanisms. To address these limitations and imbalances, here we draw together and systematically integrate information from the (bio)chemical literature, from cheminformatics, and from genome-scale metabolic models to objectively define a 'Top 30' list of damage-prone metabolites. A foundational part of this process was to derive general reaction rules for the damage chemistries involved. The criteria for a 'Top 30' metabolite included predicted chemical reactivity, essentiality, and occurrence in diverse organisms. We also explain how the damage chemistry reaction rules ('operators') are implemented in the Chemical-Damage-MINE (CD-MINE) database (minedatabase.mcs.anl.gov/#/top30) to provide a predictive tool for many additional potential metabolite damage products. Lastly, we illustrate how defining a 'Top 30' list can drive genomics-enabled discovery of the enzymes of previously unrecognized damage-control systems, and how applying chemical damage reaction rules can help identify previously unknown peaks in metabolomics profiles. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

Chemicals in Household Products: Problems with Solutions

NASA Astrophysics Data System (ADS)

Glegg, Gillian A.; Richards, Jonathan P.

2007-12-01

The success of a regulatory regime in decreasing point-source emissions of some harmful chemicals has highlighted the significance of other sources. A growing number of potentially harmful chemicals have been incorporated into an expanding range of domestic household products and are sold worldwide. Tighter regulation has been proposed, and the European Commission has introduced the Regulation on the Registration, Evaluation, and Authorisation of Chemicals to address this concern. However, it is clear that in addition to the regulation, there is a potential to effect change through retailer and consumer attitudes and behaviours. Interviews were conducted with 7 key stakeholder groups to identify critical issues, which were then explored using a public survey questionnaire (1,008 respondents) and 8 subsequent focus groups. The findings demonstrated that the issue of chemicals in products is of concern to consumers for reasons of personal health rather than environmental protection. Key obstacles to the wider purchase of “green-alternative” products included perceived high cost and poor performance, lack of availability of products, and poor information concerning such products. Although improved regulation was seen as part of the solution, consumers must also play a role. It was clear from this study that consumers are not currently able to make informed choices about the chemicals they use but that they would be receptive to moving toward a more sustainable use of chemicals in the future if empowered to do so.

Chemicals in household products: problems with solutions.

PubMed

Glegg, Gillian A; Richards, Jonathan P

2007-12-01

The success of a regulatory regime in decreasing point-source emissions of some harmful chemicals has highlighted the significance of other sources. A growing number of potentially harmful chemicals have been incorporated into an expanding range of domestic household products and are sold worldwide. Tighter regulation has been proposed, and the European Commission has introduced the Regulation on the Registration, Evaluation, and Authorisation of Chemicals to address this concern. However, it is clear that in addition to the regulation, there is a potential to effect change through retailer and consumer attitudes and behaviours. Interviews were conducted with 7 key stakeholder groups to identify critical issues, which were then explored using a public survey questionnaire (1,008 respondents) and 8 subsequent focus groups. The findings demonstrated that the issue of chemicals in products is of concern to consumers for reasons of personal health rather than environmental protection. Key obstacles to the wider purchase of "green-alternative" products included perceived high cost and poor performance, lack of availability of products, and poor information concerning such products. Although improved regulation was seen as part of the solution, consumers must also play a role. It was clear from this study that consumers are not currently able to make informed choices about the chemicals they use but that they would be receptive to moving toward a more sustainable use of chemicals in the future if empowered to do so.

Enhancement of surface damage resistance by selective chemical removal of CeO2

NASA Astrophysics Data System (ADS)

Kamimura, Tomosumi; Motokoshi, Shinji; Sakamoto, Takayasu; Jitsuno, Takahisa; Shiba, Haruya; Akamatsu, Shigenori; Horibe, Hideo; Okamoto, Takayuki; Yoshida, Kunio

2005-02-01

The laser-induced damage threshold of polished fused silica surfaces is much lower than the damage threshod of its bulk. It is well known that contaminations of polished surface are one of the causes of low threshold of laser-induced surface damage. Particularly, polishing contamination such as cerium dioxide (CeO2) compound used in optical polishing process is embedded inside the surface layer, and cannot be removed by conventional cleaning. For the enhancement of surface damage resistance, various surface treatments have been applied to the removal of embedded polishing compound. In this paper, we propose a new method using slective chemical removal with high-temperature sulfuric acid (H2SO4). Sulfuric acid could dissolve only CeO2 from the fused silica surface. The surface roughness of fused silica treated H2SO4 was kept through the treatment process. At the wavelength of 355 nm, the surface damage threshold was drastically improved to the nearly same as bulk quality. However, the effect of our treatment was not observed at the wavelength of 1064 nm. The comparison with our previous results obtained from other surface treatments will be discussed.

Engineering microbes for efficient production of chemicals

DOEpatents

Gong, Wei; Dole, Sudhanshu; Grabar, Tammy; Collard, Andrew Christopher; Pero, Janice G; Yocum, R Rogers

2015-04-28

This present invention relates to production of chemicals from microorganisms that have been genetically engineered and metabolically evolved. Improvements in chemical production have been established, and particular mutations that lead to those improvements have been identified. Specific examples are given in the identification of mutations that occurred during the metabolic evolution of a bacterial strain genetically engineered to produce succinic acid. This present invention also provides a method for evaluating the industrial applicability of mutations that were selected during the metabolic evolution for increased succinic acid production. This present invention further provides microorganisms engineered to have mutations that are selected during metabolic evolution and contribute to improved production of succinic acid, other organic acids and other chemicals of commercial interest.

76 FR 1067 - Testing of Certain High Production Volume Chemicals; Second Group of Chemicals

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-07

... 2070-AD16 Testing of Certain High Production Volume Chemicals; Second Group of Chemicals AGENCY... processors of certain high production volume (HPV) chemical substances to conduct testing to obtain screening... potentially affected by this action if you manufacture (defined by statute to include import) or process any...

Effects of chemical alternation on damage accumulation in concentrated solid-solution alloys

DOE PAGES

Ullah, Mohammad W.; Xue, Haizhou; Velisa, Gihan; ...

2017-06-23

Single-phase concentrated solid-solution alloys (SP-CSAs) have recently gained unprecedented attention due to their promising properties. To understand effects of alloying elements on irradiation-induced defect production, recombination and evolution, an integrated study of ion irradiation, ion beam analysis and atomistic simulations are carried out on a unique set of model crystals with increasing chemical complexity, from pure Ni to Ni 80Fe 20, Ni 50Fe 50, and Ni 80Cr 20 binaries, and to a more complex Ni 40Fe 40Cr 20 alloy. Both experimental and simulation results suggest that the binary and ternary alloys exhibit higher radiation resistance than elemental Ni. The modelingmore » work predicts that Ni 40Fe 40Cr 20 has the best radiation tolerance, with the number of surviving Frenkel pairs being factors of 2.0 and 1.4 lower than pure Ni and the 80:20 binary alloys, respectively. While the reduced defect mobility in SP-CSAs is identified as a general mechanism leading to slower growth of large defect clusters, the effect of specific alloying elements on suppression of damage accumulation is clearly demonstrated. This work suggests that concentrated solid-solution provides an effective way to enhance radiation tolerance by creating elemental alternation at the atomic level. The demonstrated chemical effects on defect dynamics may inspire new design principles of radiation-tolerant structural alloys for advanced energy systems.« less

Damage and recovery of skin barrier function after glycolic acid chemical peeling and crystal microdermabrasion.

PubMed

Song, Ji Youn; Kang, Hyun A; Kim, Mi-Yeon; Park, Young Min; Kim, Hyung Ok

2004-03-01

Superficial chemical peeling and microdermabrasion have become increasingly popular methods for producing facial rejuvenation. However, there are few studies reporting the skin barrier function changes after these procedures. To evaluate objectively the degree of damage visually and the time needed for the skin barrier function to recover after glycolic acid peeling and aluminum oxide crystal microdermabrasion using noninvasive bioengineering methods. Superficial chemical peeling using 30%, 50%, and 70% glycolic acid and aluminum oxide crystal microdermabrasion were used on the volar forearm of 13 healthy women. The skin response was measured by a visual observation and using an evaporimeter, corneometer, and colorimeter before and after peeling at set time intervals. Both glycolic acid peeling and aluminum oxide crystal microdermabrasion induced significant damage to the skin barrier function immediately after the procedure, and the degree of damage was less severe after the aluminum oxide crystal microdermabrasion compared with glycolic acid peeling. The damaged skin barrier function had recovered within 24 hours after both procedures. The degree of erythema induction was less severe after the aluminum oxide crystal microdermabrasion compared with the glycolic acid peeling procedure. The degree of erythema induced after the glycolic acid peeling procedure was not proportional to the peeling solution concentration used. The erythema subsided within 1 day after the aluminum oxide crystal microdermabrasion procedure and within 4 days after the glycolic acid peeling procedure. These results suggest that the skin barrier function is damaged after the glycolic acid peeling and aluminum oxide crystal microdermabrasion procedure but recovers within 1 to 4 days. Therefore, repeating the superficial peeling procedure at 2-week intervals will allow sufficient time for the damaged skin to recover its barrier function.

Entropy Production in Chemical Reactors

NASA Astrophysics Data System (ADS)

Kingston, Diego; Razzitte, Adrián C.

2017-06-01

We have analyzed entropy production in chemically reacting systems and extended previous results to the two limiting cases of ideal reactors, namely continuous stirred tank reactor (CSTR) and plug flow reactor (PFR). We have found upper and lower bounds for the entropy production in isothermal systems and given expressions for non-isothermal operation and analyzed the influence of pressure and temperature in entropy generation minimization in reactors with a fixed volume and production. We also give a graphical picture of entropy production in chemical reactions subject to constant volume, which allows us to easily assess different options. We show that by dividing a reactor into two smaller ones, operating at different temperatures, the entropy production is lowered, going as near as 48 % less in the case of a CSTR and PFR in series, and reaching 58 % with two CSTR. Finally, we study the optimal pressure and temperature for a single isothermal PFR, taking into account the irreversibility introduced by a compressor and a heat exchanger, decreasing the entropy generation by as much as 30 %.

Endocrine Disruptors and Asthma-Associated Chemicals in Consumer Products

PubMed Central

Nishioka, Marcia; Standley, Laurel J.; Perovich, Laura J.; Brody, Julia Green; Rudel, Ruthann A.

2012-01-01

Background: Laboratory and human studies raise concerns about endocrine disruption and asthma resulting from exposure to chemicals in consumer products. Limited labeling or testing information is available to evaluate products as exposure sources. Objectives: We analytically quantified endocrine disruptors and asthma-related chemicals in a range of cosmetics, personal care products, cleaners, sunscreens, and vinyl products. We also evaluated whether product labels provide information that can be used to select products without these chemicals. Methods: We selected 213 commercial products representing 50 product types. We tested 42 composited samples of high-market-share products, and we tested 43 alternative products identified using criteria expected to minimize target compounds. Analytes included parabens, phthalates, bisphenol A (BPA), triclosan, ethanolamines, alkylphenols, fragrances, glycol ethers, cyclosiloxanes, and ultraviolet (UV) filters. Results: We detected 55 compounds, indicating a wide range of exposures from common products. Vinyl products contained > 10% bis(2-ethylhexyl) phthalate (DEHP) and could be an important source of DEHP in homes. In other products, the highest concentrations and numbers of detects were in the fragranced products (e.g., perfume, air fresheners, and dryer sheets) and in sunscreens. Some products that did not contain the well-known endocrine-disrupting phthalates contained other less-studied phthalates (dicyclohexyl phthalate, diisononyl phthalate, and di-n-propyl phthalate; also endocrine-disrupting compounds), suggesting a substitution. Many detected chemicals were not listed on product labels. Conclusions: Common products contain complex mixtures of EDCs and asthma-related compounds. Toxicological studies of these mixtures are needed to understand their biological activity. Regarding epidemiology, our findings raise concern about potential confounding from co-occurring chemicals and misclassification due to variability in

Apitherapy products enhance the recovery of CCL4-induced hepatic damages in rats.

PubMed

Saral, Özlem; Yildiz, Oktay; Aliyazicioğlu, Rezzan; Yuluğ, Esin; Canpolat, Sinan; Öztürk, Ferhat; Kolayli, Sevgi

2016-01-05

Our objective was to identify the antioxidant properties of honeybee products from Turkey, chestnut honey, pollen, propolis, and royal jelly, and their hepatoprotective activity against CCl4-induced hepatic damage in rats. Animals were fed with honeybee products for 7 days following CCl4 injection. Development of liver damage and oxidative stress were monitored by measuring the activities of the enzymes alanine transaminase, aspartate transaminase, malondialdehyde, superoxide dismutase, and catalase. Antioxidant capacities of the bee products were identified using FRAP and DPPH assays, as well as by measuring total phenolic and flavonoid contents. The antioxidant activities of the honeybee products were highest in propolis, followed, in order, by pollen, honey, and royal jelly. Despite their different levels of antioxidant capacity, their roles in the prevention of liver damage induced by CCl4 were very similar, which can be explained through their bioavailability to the treated animals. Our results suggest that honey, propolis, pollen, and royal jelly significantly enhanced the healing of CCl4-induced liver damage, partially due to their antioxidant properties and bioavailability.

76 FR 4549 - Testing of Certain High Production Volume Chemicals; Second Group of Chemicals; Technical Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-26

... Testing of Certain High Production Volume Chemicals; Second Group of Chemicals; Technical Correction... production volume (HPV) chemical substances to obtain screening level data for health and environmental effects and chemical fate. This document is being issued to correct a typographical error concerning the...

DETECTION OF LOW DOSE RADIATION-AND CHEMICALLY-INDUCED DNA DAMAGE USING TEMPERATURE DIFFERENTIAL FLUORESCENCE ASSAYS

EPA Science Inventory

Rapid, sensitive and simple assays for radiation- and chemically-induced DNA damage can be of significant benefit to a number of fields including radiation biology, clinical research, and environmental monitoring. Although temperature-induced DNA strand separation has been use...

Production of chemicals and fuels from biomass

DOEpatents

Qiao, Ming; Woods, Elizabeth; Myren, Paul; Cortright, Randy; Kania, John

2018-01-23

Methods, reactor systems, and catalysts are provided for converting in a continuous process biomass to fuels and chemicals, including methods of converting the water insoluble components of biomass, such as hemicellulose, cellulose and lignin, to volatile C.sub.2+O.sub.1-2 oxygenates, such as alcohols, ketones, cyclic ethers, esters, carboxylic acids, aldehydes, and mixtures thereof. In certain applications, the volatile C.sub.2+O.sub.1-2 oxygenates can be collected and used as a final chemical product, or used in downstream processes to produce liquid fuels, chemicals and other products.

Development of haemostatic decontaminants for treatment of wounds contaminated with chemical warfare agents. 3: Evaluation of in vitro topical decontamination efficacy using damaged skin.

PubMed

Lydon, Helen L; Hall, Charlotte A; Dalton, Christopher H; Chipman, J Kevin; Graham, John S; Chilcott, Robert P

2017-08-01

Previous studies have demonstrated that haemostatic products with an absorptive mechanism of action retain their clotting efficiency in the presence of toxic materials and are effective in decontaminating chemical warfare (CW) agents when applied to normal, intact skin. The purpose of this in vitro study was to assess three candidate haemostatic products for effectiveness in the decontamination of superficially damaged porcine skin exposed to the radiolabelled CW agents, soman (GD), VX and sulphur mustard (HD). Controlled physical damage (removal of the upper 100 μm skin layer) resulted in a significant enhancement of the dermal absorption of all three CW agents. Of the haemostatic products assessed, WoundStat™ was consistently the most effective, being equivalent in performance to a standard military decontaminant (fuller's earth). These data suggest that judicious application of haemostatic products to wounds contaminated with CW agents may be a viable option for the clinical management of casualties presenting with contaminated, haemorrhaging injuries. Further studies using a relevant animal model are required to confirm the potential clinical efficacy of WoundStat™ for treating wounds contaminated with CW agents. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

. Cheminformatic exploration of the chemical landscape of consumer products

EPA Science Inventory

Although Consumer products are a primary source of chemical exposures, little information is available on the chemical ingredients of these products and the concentrations at which they are present. To address this data gap, we have created a database of chemicals in consumer pro...

Production of chemicals and fuels from biomass

DOEpatents

Woods, Elizabeth; Qiao, Ming; Myren, Paul; Cortright, Randy D.; Kania, John

2015-12-15

Described are methods, reactor systems, and catalysts for converting biomass to fuels and chemicals in a batch and/or continuous process. The process generally involves the conversion of water insoluble components of biomass, such as hemicellulose, cellulose and lignin, to volatile C.sub.2+O.sub.1-2 oxygenates, such as alcohols, ketones, cyclic ethers, esters, carboxylic acids, aldehydes, and mixtures thereof. In certain applications, the volatile C.sub.2+O.sub.1-2 oxygenates can be collected and used as a final chemical product, or used in downstream processes to produce liquid fuels, chemicals and other products.

Engineering cyanobacteria for fuels and chemicals production.

PubMed

Zhou, Jie; Li, Yin

2010-03-01

The world's energy and global warming crises call for sustainable, renewable, carbon-neutral alternatives to replace fossil fuel resources. Currently, most biofuels are produced from agricultural crops and residues, which lead to concerns about food security and land shortage. Compared to the current biofuel production system, cyanobacteria, as autotrophic prokaryotes, do not require arable land and can grow to high densities by efficiently using solar energy, CO(2), water, and inorganic nutrients. Moreover, powerful genetic techniques of cyanobacteria have been developed. For these reasons, cyanobacteria, which carry out oxygenic photosynthesis, are attractive hosts for production of fuels and chemicals. Recently, several chemicals including ethanol, isobutanol and isoprene have been produced by engineered cyanobacteria directly using solar energy, CO(2), and water. Cyanobacterium is therefore a potential novel cell factory for fuels and chemicals production to address global energy security and climate change issues.

Cyanobacterial metabolic engineering for biofuel and chemical production.

PubMed

Oliver, Neal J; Rabinovitch-Deere, Christine A; Carroll, Austin L; Nozzi, Nicole E; Case, Anna E; Atsumi, Shota

2016-12-01

Rising levels of atmospheric CO 2 are contributing to the global greenhouse effect. Large scale use of atmospheric CO 2 may be a sustainable and renewable means of chemical and liquid fuel production to mitigate global climate change. Photosynthetic organisms are an ideal platform for efficient, natural CO 2 conversion to a broad range of chemicals. Cyanobacteria are especially attractive for these purposes, due to their genetic malleability and relatively fast growth rate. Recent years have yielded a range of work in the metabolic engineering of cyanobacteria and have led to greater knowledge of the host metabolism. Understanding of endogenous and heterologous carbon regulation mechanisms leads to the expansion of productive capacity and chemical variety. This review discusses the recent progress in metabolic engineering of cyanobacteria for biofuel and bulk chemical production since 2014. Copyright © 2016 Elsevier Ltd. All rights reserved.

The U.S. Chemical Industry, the Products It Makes

ERIC Educational Resources Information Center

Chemical and Engineering News, 1972

1972-01-01

This section of the annual report on the chemical industry presents data on these areas of chemical production: growth rates, man-made fibers; the 50 largest volume chemicals, major inorganics and organics, plastics, drugs, magnesium, and paint. Includes production figures for 1961, 1969, 1970, 1971 and percent change for 1970-71 and for 1961-71.…

Control excess stock and calculating damaged products as the effort to increase revenue (case study of SME FBS)

NASA Astrophysics Data System (ADS)

Nurhasanah, N.; Mardhika, D. A.; Tanjung, W.; Gayatri, A. M.; Suri, Q. A.; Jingga; Safitri, R.; Supriyanto, A.

2017-12-01

Of small and medium scale (SME) is a business engaged in production. The growth product innovation of each year to year made competitiveness every SME very tight, and the sales must be high that avoid goods the product last year will be tough sold in the following year. Forecasting demand is needed so that no its production. In production process, besides products should also be considered about damaged products, resulting in a loss. In this study, researchers conducted a observations on SME FBS producing pants, shirts and shirts. SME FBS not having planning previous production, also in any period of production there always products be damaged. This study attempts to increase their SME FBS by controlling waste products, and those damaged products. According to the research conducted other products in some excess pants 1609 unit, and the shirts 187911 unit, and increase the income through control over the excess product obtained by 1% to the pants, and 52% to the shirts. For damaged product on period last year and future, increase 0.07% if the damaged on shirts can be sold, and 0.29% on pants if the broken sold.

Chemical Characterization and Reactivity Testing of Fuel-Oxidizer Reaction Product (Test Report)

NASA Technical Reports Server (NTRS)

1996-01-01

The product of incomplete reaction of monomethylhydrazine (MMH) and nitrogen tetroxide (NTO) propellants, or fuel-oxidizer reaction product (FORP), has been hypothesized as a contributory cause of an anomaly which occurred in the chamber pressure (PC) transducer tube on the Reaction Control Subsystem (RCS) aft thruster 467 on flight STS-51. A small hole was found in the titanium-alloy PC tube at the first bend below the pressure transducer. It was surmised that the hole may have been caused by heat and pressure resulting from ignition of FORP. The NASA Johnson Space Center (JSC) White Sands Test Facility (WSTF) was requested to define the chemical characteristics of FORP, characterize its reactivity, and simulate the events in a controlled environment which may have lead to the Pc-tube failure. Samples of FORP were obtained from the gas-phase reaction of MMH with NTO under laboratory conditions, the pulsed firings of RCS thrusters with modified PC tubes using varied oxidizer or fuel lead times, and the nominal RCS thruster firings at WSTF and Kaiser-Marquardt. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), accelerating rate calorimetry (ARC), ion chromatography (IC), inductively coupled plasma (ICP) spectrometry, thermogravimetric analysis (TGA) coupled to FTIR (TGA/FTIR), and mechanical impact testing were used to qualitatively and quantitatively characterize the chemical, thermal, and ignition properties of FORP. These studies showed that the composition of FORP is variable but falls within a limited range of compositions that depends on the fuel loxidizer ratio at the time of formation, composition of the post-formation atmosphere (reducing or oxidizing), and reaction or postreaction temperature. A typical composition contains methylhydrazinium nitrate (MMHN), ammonium nitrate (AN), methylammonium nitrate (MAN), and trace amounts of hydrazinium nitrate and 1,1-dimethylhydrazinium nitrate. The thermal decomposition

Microbial production of building block chemicals and polymers.

PubMed

Lee, Jeong Wook; Kim, Hyun Uk; Choi, Sol; Yi, Jongho; Lee, Sang Yup

2011-12-01

Owing to our increasing concerns on the environment, climate change, and limited natural resources, there has recently been considerable effort exerted to produce chemicals and materials from renewable biomass. Polymers we use everyday can also be produced either by direct fermentation or by polymerization of monomers that are produced by fermentation. Recent advances in metabolic engineering combined with systems biology and synthetic biology are allowing us to more systematically develop superior strains and bioprocesses for the efficient production of polymers and monomers. Here, we review recent trends in microbial production of building block chemicals that can be subsequently used for the synthesis of polymers. Also, recent successful cases of direct one-step production of polymers are reviewed. General strategies for the production of natural and unnatural platform chemicals are described together with representative examples. Copyright © 2011 Elsevier Ltd. All rights reserved.

Vulnerability assessment of chemical industry facilities in South Korea based on the chemical accident history

NASA Astrophysics Data System (ADS)

Heo, S.; Lee, W. K.; Jong-Ryeul, S.; Kim, M. I.

2016-12-01

The use of chemical compounds are keep increasing because of their use in manufacturing industry. Chemical accident is growing as the consequence of the chemical use increment. Devastating damages from chemical accidents are far enough to aware people's cautious about the risk of the chemical accident. In South Korea, Gumi Hydrofluoric acid leaking accident triggered the importance of risk management and emphasized the preventing the accident over the damage reducing process after the accident occurs. Gumi accident encouraged the government data base construction relate to the chemical accident. As the result of this effort Chemical Safety-Clearing-house (CSC) have started to record the chemical accident information and damages according to the Harmful Chemical Substance Control Act (HCSC). CSC provide details information about the chemical accidents from 2002 to present. The detail informations are including title of company, address, business type, accident dates, accident types, accident chemical compounds, human damages inside of the chemical industry facilities, human damage outside of the chemical industry facilities, financial damages inside of the chemical industry facilities, and financial damages outside of the chemical industry facilities, environmental damages and response to the chemical accident. Collected the chemical accident history of South Korea from 2002 to 2015 and provide the spatial information to the each accident records based on their address. With the spatial information, compute the data on ArcGIS for the spatial-temporal analysis. The spatial-temporal information of chemical accident is organized by the chemical accident types, damages, and damages on environment and conduct the spatial proximity with local community and environmental receptors. Find the chemical accident vulnerable area of South Korea from 2002 to 2015 and add the vulnerable area of total period to examine the historically vulnerable area from the chemical accident in

Effect of complex polyphenols and tannins from red wine (WCPT) on chemically induced oxidative DNA damage in the rat.

PubMed

Casalini, C; Lodovici, M; Briani, C; Paganelli, G; Remy, S; Cheynier, V; Dolara, P

1999-08-01

Flavonoids are polyphenolic antioxidants occurring in vegetables and fruits as well as beverages such as tea and wine which have been thought to influence oxidative damage. We wanted to verify whether a complex mixture of wine tannins (wine complex polyphenols and tannins, WCPT) prevent chemically-induced oxidative DNA damage in vivo. Oxidative DNA damage was evaluated by measuring the ratio of 8-hydroxy-2'-deoxyguanosine (80HdG)/ 2-deoxyguanosine (2dG) x 10(-6) in hydrolyzed DNA using HPLC coupled with electrochemical and UV detectors. We treated rats with WCPT (57 mg/kg p.o.) for 14 d, a dose 10-fold higher than what a moderate wine drinker would be exposed to. WCPT administration significantly reduced the ratio of 80HdG/2dG x 10(-6) in liver DNA obtained from rats treated with 2-nitropropane (2NP) relative to controls administered 2NP only (33. 3 +/- 2.5 vs. 44.9 +/- 3.2 x 10(-6) 2dG; micro +/- SE; p<0.05). On the contrary, pretreatment with WCPT for 10 d did not protect the colon mucosa from oxidative DNA damage induced by 1, 2-dimethylhydrazine (DMH). 2NP and DMH are hepatic and colon carcinogens, respectively, capable of inducing oxidative DNA damage. WCPT have protective action against some types of chemically-induced oxidative DNA damage in vivo.

Hazard Classification of Household Chemical Products in Korea according to the Globally Harmonized System of Classification and labeling of Chemicals.

PubMed

Kim, Kyung-Hee; Song, Dae-Jong; Yu, Myeong-Hyun; Park, Yuon-Shin; Noh, Hye-Ran; Kim, Hae-Joon; Choi, Jae-Wook

2013-07-16

This study was conducted to review the validity of the need for the application of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) to household chemical products in Korea. The study also aimed to assess the severity of health and environmental hazards of household chemical products using the GHS. 135 products were classified as 'cleaning agents and polishing agents' and 98 products were classified as 'bleaches, disinfectants, and germicides.' The current status of carcinogenic classification of GHS and carcinogenicity was examined for 272 chemical substances contained in household chemical products by selecting the top 11 products for each of the product categories. In addition, the degree of toxicity was assessed through analysis of whether the standard of the Republic of Korea's regulations on household chemical products had been exceeded or not. According to GHS health and environmental hazards, "acute toxicity (oral)" was found to be the highest for two product groups, 'cleaning agents and polishing agents', and 'bleaches, disinfectants, and germicides' (result of classification of 233 household chemical products) at 37.8% and 52.0% respectively. In an analysis of carcinogenicity assuming a threshold of IARC 2B for the substances in household chemical products, we found 'cleaning agents and polishing agents' to contain 12 chemical substances and 'bleaches, disinfectants, and germicides' 11 chemical substances. Some of the household chemical products were found to have a high hazard level including acute toxicity and germ cell mutagenicity, carcinogenicity, and reproductive toxicity. Establishing a hazard information delivery system including the application of GHS to household chemical products in Korea is urgent as well.

Mitigation of laser damage on National Ignition Facility optics in volume production

NASA Astrophysics Data System (ADS)

Folta, James; Nostrand, Mike; Honig, John; Wong, Nan; Ravizza, Frank; Geraghty, Paul; Taranowski, Mike; Johnson, Gary; Larkin, Glenn; Ravizza, Doug; Peterson, John; Welday, Brian; Wegner, Paul

2013-12-01

The National Ignition Facility has recently achieved the milestone of delivering over 1.8 MJ and 500 TW of 351 nm laser energy and power on target, which required average fluences up to 9 J/cm2 (3 ns equivalent) in the final optics system. Commercial fused silica laser-grade UV optics typically have a maximum operating threshold of 5 J/cm2. We have developed an optics recycling process which enables NIF to operate above the laser damage initiation and growth thresholds. We previously reported a method to mitigate laser damage with laser ablation of the damage site to leave benign cone shaped pits. We have since developed a production facility with four mitigation systems capable of performing the mitigation protocols on full-sized (430 mm) optics in volume production. We have successfully repaired over 700 NIF optics (unique serial numbers), some of which have been recycled as many as 11 times. We describe the mitigation systems, the optics recycle loop process, and optics recycle production data.

Consumer product chemical weight fractions from ingredient lists.

PubMed

Isaacs, Kristin K; Phillips, Katherine A; Biryol, Derya; Dionisio, Kathie L; Price, Paul S

2018-05-01

Assessing human exposures to chemicals in consumer products requires composition information. However, comprehensive composition data for products in commerce are not generally available. Many consumer products have reported ingredient lists that are constructed using specific guidelines. A probabilistic model was developed to estimate quantitative weight fraction (WF) values that are consistent with the rank of an ingredient in the list, the number of reported ingredients, and labeling rules. The model provides the mean, median, and 95% upper and lower confidence limit WFs for ingredients of any rank in lists of any length. WFs predicted by the model compared favorably with those reported on Material Safety Data Sheets. Predictions for chemicals known to provide specific functions in products were also found to reasonably agree with reported WFs. The model was applied to a selection of publicly available ingredient lists, thereby estimating WFs for 1293 unique ingredients in 1123 products in 81 product categories. Predicted WFs, although less precise than reported values, can be estimated for large numbers of product-chemical combinations and thus provide a useful source of data for high-throughput or screening-level exposure assessments.

Implementing the Use of Chemical-Free Products in a Perinatal Unit.

PubMed

Brower, Anne; Trefz, Lisa; Burns, Catherine

2015-01-01

To develop a process to identify, adopt, and increase individual awareness of the use of chemical-free products in perinatal hospital units and to develop leadership skills of the fellow/mentor pair through the Sigma Theta Tau International Maternal-Child Health Nurse Leadership Academy (STTI MCHNLA). Pretest/posttest quality improvement project. Tertiary care 80-bed perinatal unit. Mothers and newborns on perinatal unit. The chemical hazard ratings of products currently in use and new products were examined and compared. Chemical-free products were selected and introduced to the hospital system, and education programs were provided for staff and patients. We implemented leadership tools taught at the STTI MCHNLA to facilitate project success. Pre- and postproject evaluations were used to determine interest in the use of chemical-free products and satisfaction with use of the new products. Cost savings were measured. Products currently in use contained potentially harmful chemicals. New, chemical-free products were identified and adopted into practice. Participants were interested in using chemical-free products. Once new products were available, 71% of participants were positive about using them. The fellow and mentor experienced valuable leadership growth throughout the project. The change to chemical-free products has positioned the organization and partner hospitals as community leaders that set a health standard to reduce environmental exposure for patients, families, and staff. The fellow and mentor learned new skills to assist in practice changes in a large organization by using the tools shared in the STTI MCHNLA. © 2015 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses.

Radiation damage in WC studied with MD simulations

NASA Astrophysics Data System (ADS)

Träskelin, P.; Björkas, C.; Juslin, N.; Vörtler, K.; Nordlund, K.

2007-04-01

Studying radiation damage in tungsten carbide (WC) is of importance due to its applications in fusion reactors. We have used molecular dynamics to study both deuterium induced sputtering and modification of WC surfaces and collision cascades in bulk WC. For collision cascades in bulk WC we note a massive recombination and major elemental asymmetry for the damage. Studying the erosion of WC surfaces, we find that C can erode through swift chemical sputtering, while W does not sputter more easily than from pure W. The amorphization of the surface and the D-content due to the D bombardment is important for the damage production and sputtering process.

Dynamic extrafloral nectar production: the timing of leaf damage affects the defensive response in Senna mexicana var. chapmanii (Fabaceae).

PubMed

Jones, Ian M; Koptur, Suzanne

2015-01-01

• Extrafloral nectar (EFN) mediates food for protection mutualisms between plants and defensive insects. Understanding sources of variation in EFN production is important because such variations may affect the number and identity of visitors and the effectiveness of plant defense. We investigated the influence of plant developmental stage, time of day, leaf age, and leaf damage on EFN production in Senna mexicana var. chapmanii. The observed patterns of variation in EFN production were compared with those predicted by optimal defense theory.• Greenhouse experiments with potted plants were conducted to determine how plant age, time of day, and leaf damage affected EFN production. A subsequent field study was conducted to determine how leaf damage, and the resulting increase in EFN production, affected ant visitation in S. chapmanii.• More nectar was produced at night and by older plants. Leaf damage resulted in increased EFN production, and the magnitude of the response was greater in plants damaged in the morning than those damaged at night. Damage to young leaves elicited a stronger defensive response than damage to older leaves, in line with optimal defense theory. Damage to the leaves of S. chapmanii also resulted in significantly higher ant visitation in the field.• Extrafloral nectar is an inducible defense in S. chapmanii. Developmental variations in its production support the growth differentiation balance hypothesis, while within-plant variations and damage responses support optimal defense theory. © 2015 Botanical Society of America, Inc.

Hazard Classification of Household Chemical Products in Korea according to the Globally Harmonized System of Classification and labeling of Chemicals

PubMed Central

2013-01-01

Objectives This study was conducted to review the validity of the need for the application of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) to household chemical products in Korea. The study also aimed to assess the severity of health and environmental hazards of household chemical products using the GHS. Methods 135 products were classified as ‘cleaning agents and polishing agents’ and 98 products were classified as ‘bleaches, disinfectants, and germicides.’ The current status of carcinogenic classification of GHS and carcinogenicity was examined for 272 chemical substances contained in household chemical products by selecting the top 11 products for each of the product categories. In addition, the degree of toxicity was assessed through analysis of whether the standard of the Republic of Korea’s regulations on household chemical products had been exceeded or not. Results According to GHS health and environmental hazards, “acute toxicity (oral)” was found to be the highest for two product groups, ‘cleaning agents and polishing agents’, and ‘bleaches, disinfectants, and germicides’ (result of classification of 233 household chemical products) at 37.8% and 52.0% respectively. In an analysis of carcinogenicity assuming a threshold of IARC 2B for the substances in household chemical products, we found ‘cleaning agents and polishing agents’ to contain 12 chemical substances and ‘bleaches, disinfectants, and germicides’ 11 chemical substances. Conclusion Some of the household chemical products were found to have a high hazard level including acute toxicity and germ cell mutagenicity, carcinogenicity, and reproductive toxicity. Establishing a hazard information delivery system including the application of GHS to household chemical products in Korea is urgent as well. PMID:24472347

Cyanobacteria: Promising biocatalysts for sustainable chemical production.

PubMed

Knoot, Cory J; Ungerer, Justin; Wangikar, Pramod P; Pakrasi, Himadri B

2018-04-06

Cyanobacteria are photosynthetic prokaryotes showing great promise as biocatalysts for the direct conversion of CO 2 into fuels, chemicals, and other value-added products. Introduction of just a few heterologous genes can endow cyanobacteria with the ability to transform specific central metabolites into many end products. Recent engineering efforts have centered around harnessing the potential of these microbial biofactories for sustainable production of chemicals conventionally produced from fossil fuels. Here, we present an overview of the unique chemistry that cyanobacteria have been co-opted to perform. We highlight key lessons learned from these engineering efforts and discuss advantages and disadvantages of various approaches. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Characterization and prediction of chemical functions and weight fractions in consumer products.

PubMed

Isaacs, Kristin K; Goldsmith, Michael-Rock; Egeghy, Peter; Phillips, Katherine; Brooks, Raina; Hong, Tao; Wambaugh, John F

2016-01-01

Assessing exposures from the thousands of chemicals in commerce requires quantitative information on the chemical constituents of consumer products. Unfortunately, gaps in available composition data prevent assessment of exposure to chemicals in many products. Here we propose filling these gaps via consideration of chemical functional role. We obtained function information for thousands of chemicals from public sources and used a clustering algorithm to assign chemicals into 35 harmonized function categories (e.g., plasticizers, antimicrobials, solvents). We combined these functions with weight fraction data for 4115 personal care products (PCPs) to characterize the composition of 66 different product categories (e.g., shampoos). We analyzed the combined weight fraction/function dataset using machine learning techniques to develop quantitative structure property relationship (QSPR) classifier models for 22 functions and for weight fraction, based on chemical-specific descriptors (including chemical properties). We applied these classifier models to a library of 10196 data-poor chemicals. Our predictions of chemical function and composition will inform exposure-based screening of chemicals in PCPs for combination with hazard data in risk-based evaluation frameworks. As new information becomes available, this approach can be applied to other classes of products and the chemicals they contain in order to provide essential consumer product data for use in exposure-based chemical prioritization.

9 CFR 318.16 - Pesticide chemicals and other residues in products.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Pesticide chemicals and other residues... PREPARATION OF PRODUCTS General § 318.16 Pesticide chemicals and other residues in products. (a) Nonmeat ingredients. Residues of pesticide chemicals, food additives and color additives or other substances in or on...

9 CFR 318.16 - Pesticide chemicals and other residues in products.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Pesticide chemicals and other residues... PREPARATION OF PRODUCTS General § 318.16 Pesticide chemicals and other residues in products. (a) Nonmeat ingredients. Residues of pesticide chemicals, food additives and color additives or other substances in or on...

9 CFR 318.16 - Pesticide chemicals and other residues in products.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Pesticide chemicals and other residues... PREPARATION OF PRODUCTS General § 318.16 Pesticide chemicals and other residues in products. (a) Nonmeat ingredients. Residues of pesticide chemicals, food additives and color additives or other substances in or on...

9 CFR 318.16 - Pesticide chemicals and other residues in products.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Pesticide chemicals and other residues... PREPARATION OF PRODUCTS General § 318.16 Pesticide chemicals and other residues in products. (a) Nonmeat ingredients. Residues of pesticide chemicals, food additives and color additives or other substances in or on...

Protective effect of pomegranate derived products on UVB-mediated damage in human reconstituted skin

PubMed Central

Afaq, Farrukh; Zaid, Mohammad Abu; Khan, Naghma; Dreher, Mark; Mukhtar, Hasan

2010-01-01

Solar ultraviolet (UV) radiation, particularly its UVB (290-320 nm) component, is the primary cause of many adverse biological effects including photoaging and skin cancer. UVB radiation causes DNA damage, protein oxidation and induces matrix metalloproteinases (MMPs). Photochemoprevention via the use of botanical antioxidants in affording protection to human skin against UVB damage is receiving increasing attention. Pomegranate, from the tree Punica granatum contains anthocyanins and hydrolyzable tannins and possesses strong anti-oxidant and anti-tumor promoting properties. In this study, we determined the effect of pomegranate derived products POMx juice, POMx extract and pomegranate oil (POMo) against UVB-mediated damage using reconstituted human skin (EpiDerm™ FT-200). EpiDerm was treated with POMx juice (1-2 μl/0.1 ml/well), POMx extract (5-10 μg/0.1 ml/well), and POMo (1-2 μl/0.1 ml/well) for 1 h prior to UVB (60 mJ/cm2) irradiation and was harvested 12 h post-UVB to assess protein oxidation, markers of DNA damage and photoaging by western blot analysis and immunohistochemistry. Pretreatment of Epiderm with pomegranate derived products resulted in inhibition of UVB-induced (i) cyclobutane pyrimidine dimers, (ii) 8-dihydro-2′-deoxyguanosine, (iii) protein oxidation, and (iv) PCNA protein expression. We also found that pretreatment of Epiderm with pomegranate derived products resulted in inhibition of UVB-induced (i) collagenase (MMP-1), (ii) gelatinase (MMP-2, MMP-9), (iii) stromelysin (MMP-3), (iv) marilysin (MMP-7), (v) elastase (MMP-12), and (vi) tropoelastin. Gelatin zymography revealed that pomegranate derived products inhibited UVB-induced MMP-2 and MMP-9 activities. Pomegranate derived products also caused a decrease in UVB-induced protein expression of c-Fos and phosphorylation of c-Jun. Collectively, these results suggest that all three pomegranate derived products may be useful against UVB-induced damage to human skin. PMID:19320737

Characterization of damaged skin by impedance spectroscopy: chemical damage by dimethyl sulfoxide.

PubMed

White, Erick A; Orazem, Mark E; Bunge, Annette L

2013-10-01

To relate changes in the electrochemical impedance spectra to the progression and mechanism of skin damage arising from exposure to dimethyl sulfoxide (DMSO). Electrochemical impedance spectra measured before and after human cadaver skin was treated with neat DMSO or phosphate buffered saline (control) for 1 h or less were compared with electrical circuit models representing two contrasting theories describing the progression of DMSO damage. Flux of a model lipophilic compound (p-chloronitrobenzene) was also measured. The impedance spectra collected before and after 1 h treatment with DMSO were consistent with a single circuit model; whereas, the spectra collected after DMSO exposure for 0.25 h were consistent with the model circuits observed before and after DMSO treatment for 1 h combined in series. DMSO treatments did not significantly change the flux of p-chloronitrobenzene compared to control. Impedance measurements of human skin exposed to DMSO for less than about 0.5 h were consistent with the presence of two layers: one damaged irreversibly and one unchanged. The thickness of the damaged layer increased proportional to the square-root of treatment time until about 0.5 h, when DMSO affected the entire stratum corneum. Irreversible DMSO damage altered the lipophilic permeation pathway minimally.

Suspect Screening of Chemicals in Consumer Products

EPA Science Inventory

This presentation details a pilot suspect screening analysis (SSA) of common consumer products done under the Rapid Exposure and Dosimetry project of CSS. This work presents methods which can rapidly characterize chemicals identified in consumer products including formulations (s...

Effects of the pulse width on the reactive species production and DNA damage in cancer cells exposed to atmospheric pressure microsecond-pulsed helium plasma jets

NASA Astrophysics Data System (ADS)

Joh, Hea Min; Choi, Ji Ye; Kim, Sun Ja; Kang, Tae Hong; Chung, T. H.

2017-08-01

Plasma-liquid and plasma-cell interactions were investigated using an atmospheric pressure dc microsecond-pulsed helium plasma jet. We investigated the effects of the electrical parameters such as applied voltage and pulse width (determined by the pulse frequency and duty ratio) on the production of reactive species in the gas/liquid phases and on the DNA damage responses in the cancer cells. The densities of reactive species including OH radicals were estimated inside the plasma-treated liquids using a chemical probe method, and the nitrite concentration was detected by Griess assay. Importantly, the more concentration of OH resulted in the more DNA base oxidation and breaks in human lung cancer A549 cells. The data are very suggestive that there is strong correlation between the production of OH in the plasmas/liquids and the DNA damage.

Damage-Free Smooth-Sidewall InGaAs Nanopillar Array by Metal-Assisted Chemical Etching.

PubMed

Kong, Lingyu; Song, Yi; Kim, Jeong Dong; Yu, Lan; Wasserman, Daniel; Chim, Wai Kin; Chiam, Sing Yang; Li, Xiuling

2017-10-24

Producing densely packed high aspect ratio In 0.53 Ga 0.47 As nanostructures without surface damage is critical for beyond Si-CMOS nanoelectronic and optoelectronic devices. However, conventional dry etching methods are known to produce irreversible damage to III-V compound semiconductors because of the inherent high-energy ion-driven process. In this work, we demonstrate the realization of ordered, uniform, array-based In 0.53 Ga 0.47 As pillars with diameters as small as 200 nm using the damage-free metal-assisted chemical etching (MacEtch) technology combined with the post-MacEtch digital etching smoothing. The etching mechanism of In x Ga 1-x As is explored through the characterization of pillar morphology and porosity as a function of etching condition and indium composition. The etching behavior of In 0.53 Ga 0.47 As, in contrast to higher bandgap semiconductors (e.g., Si or GaAs), can be interpreted by a Schottky barrier height model that dictates the etching mechanism constantly in the mass transport limited regime because of the low barrier height. A broader impact of this work relates to the complete elimination of surface roughness or porosity related defects, which can be prevalent byproducts of MacEtch, by post-MacEtch digital etching. Side-by-side comparison of the midgap interface state density and flat-band capacitance hysteresis of both the unprocessed planar and MacEtched pillar In 0.53 Ga 0.47 As metal-oxide-semiconductor capacitors further confirms that the surface of the resultant pillars is as smooth and defect-free as before etching. MacEtch combined with digital etching offers a simple, room-temperature, and low-cost method for the formation of high-quality In 0.53 Ga 0.47 As nanostructures that will potentially enable large-volume production of In 0.53 Ga 0.47 As-based devices including three-dimensional transistors and high-efficiency infrared photodetectors.

Consumer product chemical weight fractions from ingredient lists

EPA Science Inventory

Assessing human exposures to chemicals in consumer products requires composition information. However, comprehensive composition data for products in commerce are not generally available. Many consumer products have reported ingredient lists that are constructed using specific gu...

Combusted but not smokeless tobacco products cause DNA damage in oral cavity cells.

PubMed

Gao, Hong; Prasad, G L; Zacharias, Wolfgang

2014-05-01

The aim of this work was to investigate genomic DNA damage in human oral cavity cells after exposure to different tobacco product preparations (TPPs). The oral carcinoma cell line 101A, gingival epithelial cells HGEC, and gingival fibroblasts HGF were exposed to TPM (total particulate matter from 3R4F cigarettes), ST/CAS (2S3 smokeless tobacco extract in complete artificial saliva), and NIC (nicotine). Treatments were for 24 h using TPM at its EC-50 doses, ST/CAS and NIC at doses with equi-nicotine units, and high doses for ST/CAS and NIC. Comet assays showed that TPM, but not ST/CAS or NIC, caused substantial DNA breaks in cells; only the high ST/CAS dose caused weak DNA damage. These results were confirmed by immunofluorescence for γ-H2AX protein. These data revealed that the combusted TPP caused substantial DNA damage in all cell types, whereas the two non-combusted TPPs exerted no or only minimal DNA damage. They support epidemiologic evidence on the relative risk associated with consumption of non-combusted versus combusted tobacco products, and help to understand potential genotoxic effects of such products on oral cavity cells. Copyright © 2014 Elsevier B.V. All rights reserved.

Stochastic thermodynamics and entropy production of chemical reaction systems

NASA Astrophysics Data System (ADS)

Tomé, Tânia; de Oliveira, Mário J.

2018-06-01

We investigate the nonequilibrium stationary states of systems consisting of chemical reactions among molecules of several chemical species. To this end, we introduce and develop a stochastic formulation of nonequilibrium thermodynamics of chemical reaction systems based on a master equation defined on the space of microscopic chemical states and on appropriate definitions of entropy and entropy production. The system is in contact with a heat reservoir and is placed out of equilibrium by the contact with particle reservoirs. In our approach, the fluxes of various types, such as the heat and particle fluxes, play a fundamental role in characterizing the nonequilibrium chemical state. We show that the rate of entropy production in the stationary nonequilibrium state is a bilinear form in the affinities and the fluxes of reaction, which are expressed in terms of rate constants and transition rates, respectively. We also show how the description in terms of microscopic states can be reduced to a description in terms of the numbers of particles of each species, from which follows the chemical master equation. As an example, we calculate the rate of entropy production of the first and second Schlögl reaction models.

Estrogenic chemicals often leach from BPA-free plastic products that are replacements for BPA-containing polycarbonate products.

PubMed

Bittner, George D; Yang, Chun Z; Stoner, Matthew A

2014-05-28

Xenobiotic chemicals with estrogenic activity (EA), such as bisphenol A (BPA), have been reported to have potential adverse health effects in mammals, including humans, especially in fetal and infant stages. Concerns about safety have caused many manufacturers to use alternatives to polycarbonate (PC) resins to make hard and clear, reusable, plastic products that do not leach BPA. However, no study has focused on whether such BPA-free PC-replacement products, chosen for their perceived higher safety, especially for babies, also release other chemicals that have EA. We used two, well-established, mammalian cell-based, assays (MCF-7 and BG1Luc) to assess the EA of chemicals that leached into over 1000 saline or ethanol extracts of 50 unstressed or stressed (autoclaving, microwaving, and UV radiation) BPA-free PC-replacement products. An EA antagonist, ICI 182,780, was used to confirm that agonist activity in leachates was due to chemicals that activated the mammalian estrogen receptor. Many unstressed and stressed, PC-replacement-products made from acrylic, polystyrene, polyethersulfone, and Tritan™ resins leached chemicals with EA, including products made for use by babies. Exposure to various forms of UV radiation often increased the leaching of chemicals with EA. In contrast, some BPA-free PC-replacement products made from glycol-modified polyethylene terephthalate or cyclic olefin polymer or co-polymer resins did not release chemicals with detectable EA under any conditions tested. This hazard assessment survey showed that many BPA-free PC- replacement products still leached chemicals having significant levels of EA, as did BPA-containing PC counterparts they were meant to replace. That is, BPA-free did not mean EA-free. However, this study also showed that some PC-replacement products did not leach chemicals having significant levels of EA. That is, EA-free PC-replacement products could be made in commercial quantities at prices that compete with PC

[Cytotoxicity of chemicals used in household products: 1997- 2004].

PubMed

Ikarashi, Yoshiaki; Kaniwa, Masa-aki; Tsuchiya, Toshie

2005-01-01

The cytotoxicities of chemicals used in household products were evaluated using a neutral red (NR) uptake assay. The chemicals tested during 1997-2004 were rubber additives (accelerators, antioxidants and retarders), solvents, plasticizers and biocides, such as antimicrobials, fungicides, preservatives used in paints, paper, wood and plastic products. The cytotoxicity potential of each chemical was classified by determining the concentrations inducing 50% reduction of NR uptake into Chinese hamster fibroblast V79 cells compared to control (IC50). In vivo eye irritancy of each chemical was estimated by the IC50 value. Most biocides tested showed strong cytotoxicity and had a high probability of inducing strong eye irritation.

Synthetic Organic Chemicals: United States Production and Sales, 1976.

ERIC Educational Resources Information Center

Adams, Roger; And Others

This is the sixth annual report of the U.S. Trade Commission on domestic production and sales of synthetic organic chemicals and the raw materials from which they are made. The report consists of 15 sections, each covering a specified group (based primarily on use) of organic chemicals as follows: tar and tar crudes; primary products from…

Mediators of Inflammation-Induced Bone Damage in Arthritis and Their Control by Herbal Products

PubMed Central

Nanjundaiah, Siddaraju M.; Astry, Brian; Moudgil, Kamal D.

2013-01-01

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the synovial joints leading to bone and cartilage damage. Untreated inflammatory arthritis can result in severe deformities and disability. The use of anti-inflammatory agents and biologics has been the mainstay of treatment of RA. However, the prolonged use of such agents may lead to severe adverse reactions. In addition, many of these drugs are quite expensive. These limitations have necessitated the search for newer therapeutic agents for RA. Natural plant products offer a promising resource for potential antiarthritic agents. We describe here the cellular and soluble mediators of inflammation-induced bone damage (osteoimmunology) in arthritis. We also elaborate upon various herbal products that possess antiarthritic activity, particularly mentioning the specific target molecules. As the use of natural product supplements by RA patients is increasing, this paper presents timely and useful information about the mechanism of action of promising herbal products that can inhibit the progression of inflammation and bone damage in the course of arthritis. PMID:23476694

Omega-3 fatty acid supplementation decreases DNA damage in brain of rats subjected to a chemically induced chronic model of Tyrosinemia type II.

PubMed

Carvalho-Silva, Milena; Gomes, Lara M; Scaini, Giselli; Rebelo, Joyce; Damiani, Adriani P; Pereira, Maiara; Andrade, Vanessa M; Gava, Fernanda F; Valvassori, Samira S; Schuck, Patricia F; Ferreira, Gustavo C; Streck, Emilio L

2017-08-01

Tyrosinemia type II is an inborn error of metabolism caused by a mutation in a gene encoding the enzyme tyrosine aminotransferase leading to an accumulation of tyrosine in the body, and is associated with neurologic and development difficulties in numerous patients. Because the accumulation of tyrosine promotes oxidative stress and DNA damage, the main aim of this study was to investigate the possible antioxidant and neuroprotective effects of omega-3 treatment in a chemically-induced model of Tyrosinemia type II in hippocampus, striatum and cerebral cortex of rats. Our results showed chronic administration of L-tyrosine increased the frequency and the index of DNA damage, as well as the 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels in the hippocampus, striatum and cerebral cortex. Moreover, omega-3 fatty acid treatment totally prevented increased DNA damage in the striatum and hippocampus, and partially prevented in the cerebral cortex, whereas the increase in 8-OHdG levels was totally prevented by omega-3 fatty acid treatment in hippocampus, striatum and cerebral cortex. In conclusion, the present study demonstrated that the main accumulating metabolite in Tyrosinemia type II induce DNA damage in hippocampus, striatum and cerebral cortex, possibly mediated by free radical production, and the supplementation with omega-3 fatty acids was able to prevent this damage, suggesting that could be involved in the prevention of oxidative damage to DNA in this disease. Thus, omega-3 fatty acids supplementation to Tyrosinemia type II patients may represent a new therapeutic approach and a possible adjuvant to the curren t treatment of this disease.

Application of Nonlinear Elastic Resonance Spectroscopy For Damage Detection In Concrete: An Interesting Story

DOE Office of Scientific and Technical Information (OSTI.GOV)

Byers, Loren W.; Ten Cate, James A.; Johnson, Paul A.

2012-06-28

Nonlinear resonance ultrasound spectroscopy experiments conducted on concrete cores, one chemically and mechanically damaged by alkali-silica reactivity, and one undamaged, show that this material displays highly nonlinear wave behavior, similar to many other damaged materials. They find that the damaged sample responds more nonlinearly, manifested by a larger resonant peak and modulus shift as a function of strain amplitude. The nonlinear response indicates that there is a hysteretic influence in the stress-strain equation of state. Further, as in some other materials, slow dynamics are present. The nonlinear response they observe in concrete is an extremely sensitive indicator of damage. Ultimately,more » nonlinear wave methods applied to concrete may be used to guide mixing, curing, or other production techniques, in order to develop materials with particular desired qualities such as enhanced strength or chemical resistance, and to be used for damage inspection.« less

Sustainability of biofuels and renewable chemicals production from biomass.

PubMed

Kircher, Manfred

2015-12-01

In the sectors of biofuel and renewable chemicals the big feedstock demand asks, first, to expand the spectrum of carbon sources beyond primary biomass, second, to establish circular processing chains and, third, to prioritize product sectors exclusively depending on carbon: chemicals and heavy-duty fuels. Large-volume production lines will reduce greenhouse gas (GHG) emission significantly but also low-volume chemicals are indispensable in building 'low-carbon' industries. The foreseeable feedstock change initiates innovation, securing societal wealth in the industrialized world and creating employment in regions producing biomass. When raising the investments in rerouting to sustainable biofuel and chemicals today competitiveness with fossil-based fuel and chemicals is a strong issue. Many countries adopted comprehensive bioeconomy strategies to tackle this challenge. These public actions are mostly biased to biofuel but should give well-balanced attention to renewable chemicals as well. Copyright © 2015 Elsevier Ltd. All rights reserved.

Rational application of chemicals in response to oil spills may reduce environmental damage.

PubMed

Tamis, Jacqueline E; Jongbloed, Ruud H; Karman, Chris C; Koops, Wierd; Murk, Albertinka J

2012-04-01

Oil spills, for example those due to tanker collisions and groundings or platform accidents, can have huge adverse impacts on marine systems. The impact of an oil spill at sea depends on a number of factors, such as spill volume, type of oil spilled, weather conditions, and proximity to environmentally, economically, or socially sensitive areas. Oil spilled at sea threatens marine organisms, whole ecosystems, and economic resources in the immediate vicinity, such as fisheries, aquaculture, recreation, and tourism. Adequate response to any oil spill to minimize damage is therefore of great importance. The common response to an oil spill is to remove all visible oil from the water surface, either mechanically or by using chemicals to disperse the oil into the water column to biodegrade. This is not always the most suitable response to an oil spill, as the chemical application itself may also have adverse effects, or no response may be needed. In this article we discuss advantages and disadvantages of using chemical treatments to reduce the impact of an oil spill in relation to the conditions of the spill. The main characteristics of chemical treatment agents are discussed and presented within the context of a basic decision support scheme. Copyright © 2011 SETAC.

Role of calcium in triggering rapid ultrastructural damage in muscle: a study with chemically skinned fibres.

PubMed

Duncan, C J

1987-05-01

Agents (A23187, caffeine) believed to raise [Ca]i in vertebrate cardiac and skeletal muscles cause rapid and characteristic subcellular damage in vitro and in vivo. By using saponin-skinned amphibian pectoris cutaneous muscle and Ca-EGTA-buffered solutions it is shown that low [Ca] consistently triggers the same rapid (2-20 min), ultrastructural damage. Electron micrographs reveal a close similarity between the damaged intact and skinned preparations, namely loss of myofilament organization, specific Z-line damage, dissolution and hypercontraction bands, characteristic mitochondrial swelling and division. Where both actin and myosin filaments were lost, an underlying cytoskeletal network frequently remained, still attached to the Z-line framework. Ca was effective in skinned preparations from 5 X 10(-7) M to 8 X 10(-6) M, within the concentration range experienced by a contracting muscle. Damage was [Ca]- and time-dependent and it is suggested that it is probably the active movement of Ca ions across key membrane sites that is critical in triggering damage of the myofilament apparatus. Strontium can substitute for Ca at higher concentrations. The action of saponin suggests that the chemically skinned cell is partially activated. Ca-triggering can be bypassed experimentally by membrane-active agents or by sulphydryl agents. Ruthenium Red and trifluoperazine indirectly cause damage in the intact cell by raising [Ca]i. Studies with saponin-skinned cells and protease inhibitors show that changes in pHi, loss of ATP, Ca-activated neutral protease, or release of lysosomal enzymes (cathepsins B, D, L or H), are not involved in characteristic rapid myofilament damage.

[Chemical pollution of baby food products in the Russian Federation].

PubMed

Pivovarov, Yu P; Milushkina, O Yu; Tikhonova, y l; Aksenova, O I; Kalinovskaya, M V

One of the main problems of nutrition of children and adolescents is to assess chemical contamination of baby food products and the establishment of the relation with the health of the child population. With the entering different chemical compounds in the body of the child there can be observed disorders of the nervous, urinary, cardiovascular system, gastrointestinal tract, as well as metabolic deteriorations, degenerative processes in parenchymal organs and bone destruction. The aim of the study was to analyze data on chemical contamination of baby food products in the Russian Federation for 2012-2014. The analysis was executed on the data of Federal Information Fund of social and hygienic monitoring of the Russian Federation. There were identified priority pollutants (toxic elements, nitrites, nitrates, nitrosamines, pesticides, hydroxymethylfurfural, mycotoxins) and risk areas (the Lipetsk region, the Krasnodar Territory, the Republic of Adygea, city of Moscow, Tatarstan, the Kabardino-Balkar Republic, the Ryazan region). There are detected contamination levels not exceeding MAC (in the dynamics of the three years offollow up, on average 22%), requiring their hygienic assessment. There were determined the baby food products containing most common occurred chemical contaminants: fruits and vegetables products, canned products, canned meat, cereals, dairy products, liquid and adapted and partially adapted milk formalas. Identified data indicate to a need for further studies of chemical substances in products for children’s nutrition in order to establish the causal relationships with a various diseases and the substantiation of methodological approaches to the risk assessment of combined exposure to chemical contaminants in concentrations up to the MPC on health of children, including infants.

Evaluation of Consumer Product Co-occurrence to Inform Chemical Exposure

EPA Science Inventory

Consumer products are an important target of chemical innovation. Used daily for personal hygiene, home care, disinfection and cleaning, consumer products provide a host of benefits, and also an efficient delivery vehicle for a variety of chemicals into our homes and bodies. Al...

Estrogenic chemicals often leach from BPA-free plastic products that are replacements for BPA-containing polycarbonate products

PubMed Central

2014-01-01

Background Xenobiotic chemicals with estrogenic activity (EA), such as bisphenol A (BPA), have been reported to have potential adverse health effects in mammals, including humans, especially in fetal and infant stages. Concerns about safety have caused many manufacturers to use alternatives to polycarbonate (PC) resins to make hard and clear, reusable, plastic products that do not leach BPA. However, no study has focused on whether such BPA-free PC-replacement products, chosen for their perceived higher safety, especially for babies, also release other chemicals that have EA. Methods We used two, well-established, mammalian cell-based, assays (MCF-7 and BG1Luc) to assess the EA of chemicals that leached into over 1000 saline or ethanol extracts of 50 unstressed or stressed (autoclaving, microwaving, and UV radiation) BPA-free PC-replacement products. An EA antagonist, ICI 182,780, was used to confirm that agonist activity in leachates was due to chemicals that activated the mammalian estrogen receptor. Results Many unstressed and stressed, PC-replacement-products made from acrylic, polystyrene, polyethersulfone, and Tritan™ resins leached chemicals with EA, including products made for use by babies. Exposure to various forms of UV radiation often increased the leaching of chemicals with EA. In contrast, some BPA-free PC-replacement products made from glycol-modified polyethylene terephthalate or cyclic olefin polymer or co-polymer resins did not release chemicals with detectable EA under any conditions tested. Conclusions This hazard assessment survey showed that many BPA-free PC- replacement products still leached chemicals having significant levels of EA, as did BPA-containing PC counterparts they were meant to replace. That is, BPA-free did not mean EA-free. However, this study also showed that some PC-replacement products did not leach chemicals having significant levels of EA. That is, EA-free PC-replacement products could be made in commercial quantities at

Stress-induced DNA Damage biomarkers: Applications and limitations

NASA Astrophysics Data System (ADS)

Nikitaki, Zacharenia; Hellweg, Christine; Georgakilas, Alexandros; Ravanat, Jean-Luc

2015-06-01

A variety of environmental stresses like chemicals, UV and ionizing radiation and organism’s endogenous processes like replication stress and metabolism can lead to the generation of reactive oxygen and nitrogen species (ROS/RNS) that can attack cellular vital components like DNA, proteins and lipid membranes. Among them, much attention has been focused on DNA since DNA damages play a role in several biological disorders and aging processes. Thus, DNA damage can be used as a biomarker in a reliable and accurate way to quantify for example radiation exposure and can indicate its possible long term effects and cancer risk. Based on the type of DNA lesions detected one can hypothesize on the most probable mechanisms involved in the formation of these lesions for example in the case of UV and ionizing radiation (e.g. X- or α-, γ-rays, energetic ions, neutrons). In this review we describe the most accepted chemical pathways for DNA damage induction and the different types of DNA lesions, i.e. single, complex DNA lesions etc. that can be used as biomarkers. We critically compare DNA damage detection methods and their limitations. In addition to such DNA damage products, we suggest possible gene inductions that can be used to characterize responses to different types of stresses i.e. radiation, oxidative and replication stress, based on bioinformatic approaches and stringent meta-analysis of literature data.

An Informatics Approach to Evaluating Combined Chemical Exposures from Consumer Products: A Case Study of Asthma-Associated Chemicals and Potential Endocrine Disruptors

PubMed Central

Gabb, Henry A.; Blake, Catherine

2016-01-01

Background: Simultaneous or sequential exposure to multiple environmental stressors can affect chemical toxicity. Cumulative risk assessments consider multiple stressors but it is impractical to test every chemical combination to which people are exposed. New methods are needed to prioritize chemical combinations based on their prevalence and possible health impacts. Objectives: We introduce an informatics approach that uses publicly available data to identify chemicals that co-occur in consumer products, which account for a significant proportion of overall chemical load. Methods: Fifty-five asthma-associated and endocrine disrupting chemicals (target chemicals) were selected. A database of 38,975 distinct consumer products and 32,231 distinct ingredient names was created from online sources, and PubChem and the Unified Medical Language System were used to resolve synonymous ingredient names. Synonymous ingredient names are different names for the same chemical (e.g., vitamin E and tocopherol). Results: Nearly one-third of the products (11,688 products, 30%) contained ≥ 1 target chemical and 5,229 products (13%) contained > 1. Of the 55 target chemicals, 31 (56%) appear in ≥ 1 product and 19 (35%) appear under more than one name. The most frequent three-way chemical combination (2-phenoxyethanol, methyl paraben, and ethyl paraben) appears in 1,059 products. Further work is needed to assess combined chemical exposures related to the use of multiple products. Conclusions: The informatics approach increased the number of products considered in a traditional analysis by two orders of magnitude, but missing/incomplete product labels can limit the effectiveness of this approach. Such an approach must resolve synonymy to ensure that chemicals of interest are not missed. Commonly occurring chemical combinations can be used to prioritize cumulative toxicology risk assessments. Citation: Gabb HA, Blake C. 2016. An informatics approach to evaluating combined chemical

An Informatics Approach to Evaluating Combined Chemical Exposures from Consumer Products: A Case Study of Asthma-Associated Chemicals and Potential Endocrine Disruptors.

PubMed

Gabb, Henry A; Blake, Catherine

2016-08-01

Simultaneous or sequential exposure to multiple environmental stressors can affect chemical toxicity. Cumulative risk assessments consider multiple stressors but it is impractical to test every chemical combination to which people are exposed. New methods are needed to prioritize chemical combinations based on their prevalence and possible health impacts. We introduce an informatics approach that uses publicly available data to identify chemicals that co-occur in consumer products, which account for a significant proportion of overall chemical load. Fifty-five asthma-associated and endocrine disrupting chemicals (target chemicals) were selected. A database of 38,975 distinct consumer products and 32,231 distinct ingredient names was created from online sources, and PubChem and the Unified Medical Language System were used to resolve synonymous ingredient names. Synonymous ingredient names are different names for the same chemical (e.g., vitamin E and tocopherol). Nearly one-third of the products (11,688 products, 30%) contained ≥ 1 target chemical and 5,229 products (13%) contained > 1. Of the 55 target chemicals, 31 (56%) appear in ≥ 1 product and 19 (35%) appear under more than one name. The most frequent three-way chemical combination (2-phenoxyethanol, methyl paraben, and ethyl paraben) appears in 1,059 products. Further work is needed to assess combined chemical exposures related to the use of multiple products. The informatics approach increased the number of products considered in a traditional analysis by two orders of magnitude, but missing/incomplete product labels can limit the effectiveness of this approach. Such an approach must resolve synonymy to ensure that chemicals of interest are not missed. Commonly occurring chemical combinations can be used to prioritize cumulative toxicology risk assessments. Gabb HA, Blake C. 2016. An informatics approach to evaluating combined chemical exposures from consumer products: a case study of asthma

Early perception of stink bug damage in developing seeds of field-grown soybean induces chemical defences and reduces bug attack.

PubMed

Giacometti, Romina; Barneto, Jesica; Barriga, Lucia G; Sardoy, Pedro M; Balestrasse, Karina; Andrade, Andrea M; Pagano, Eduardo A; Alemano, Sergio G; Zavala, Jorge A

2016-08-01

Southern green stink bugs (Nezara viridula L.) invade field-grown soybean crops, where they feed on developing seeds and inject phytotoxic saliva, which causes yield reduction. Although leaf responses to herbivory are well studied, no information is available about the regulation of defences in seeds. This study demonstrated that mitogen-activated protein kinases MPK3, MPK4 and MPK6 are expressed and activated in developing seeds of field-grown soybean and regulate a defensive response after stink bug damage. Although 10-20 min after stink bug feeding on seeds induced the expression of MPK3, MPK6 and MPK4, only MPK6 was phosphorylated after damage. Herbivory induced an early peak of jasmonic acid (JA) accumulation and ethylene (ET) emission after 3 h in developing seeds, whereas salicylic acid (SA) was also induced early, and at increasing levels up to 72 h after damage. Damaged seeds upregulated defensive genes typically modulated by JA/ET or SA, which in turn reduced the activity of digestive enzymes in the gut of stink bugs. Induced seeds were less preferred by stink bugs. This study shows that stink bug damage induces seed defences, which is perceived early by MPKs that may activate defence metabolic pathways in developing seeds of field-grown soybean. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Development of a consumer product ingredient database for chemical exposure screening and prioritization.

PubMed

Goldsmith, M-R; Grulke, C M; Brooks, R D; Transue, T R; Tan, Y M; Frame, A; Egeghy, P P; Edwards, R; Chang, D T; Tornero-Velez, R; Isaacs, K; Wang, A; Johnson, J; Holm, K; Reich, M; Mitchell, J; Vallero, D A; Phillips, L; Phillips, M; Wambaugh, J F; Judson, R S; Buckley, T J; Dary, C C

2014-03-01

Consumer products are a primary source of chemical exposures, yet little structured information is available on the chemical ingredients of these products and the concentrations at which ingredients are present. To address this data gap, we created a database of chemicals in consumer products using product Material Safety Data Sheets (MSDSs) publicly provided by a large retailer. The resulting database represents 1797 unique chemicals mapped to 8921 consumer products and a hierarchy of 353 consumer product "use categories" within a total of 15 top-level categories. We examine the utility of this database and discuss ways in which it will support (i) exposure screening and prioritization, (ii) generic or framework formulations for several indoor/consumer product exposure modeling initiatives, (iii) candidate chemical selection for monitoring near field exposure from proximal sources, and (iv) as activity tracers or ubiquitous exposure sources using "chemical space" map analyses. Chemicals present at high concentrations and across multiple consumer products and use categories that hold high exposure potential are identified. Our database is publicly available to serve regulators, retailers, manufacturers, and the public for predictive screening of chemicals in new and existing consumer products on the basis of exposure and risk. Published by Elsevier Ltd.

Cyanobacterial chassis engineering for enhancing production of biofuels and chemicals.

PubMed

Gao, Xinyan; Sun, Tao; Pei, Guangsheng; Chen, Lei; Zhang, Weiwen

2016-04-01

To reduce dependence on fossil fuels and curb greenhouse effect, cyanobacteria have emerged as an important chassis candidate for producing biofuels and chemicals due to their capability to directly utilize sunlight and CO2 as the sole energy and carbon sources, respectively. Recent progresses in developing and applying various synthetic biology tools have led to the successful constructions of novel pathways of several dozen green fuels and chemicals utilizing cyanobacterial chassis. Meanwhile, it is increasingly recognized that in order to enhance productivity of the synthetic cyanobacterial systems, optimizing and engineering more robust and high-efficient cyanobacterial chassis should not be omitted. In recent years, numerous research studies have been conducted to enhance production of green fuels and chemicals through cyanobacterial chassis modifications involving photosynthesis, CO2 uptake and fixation, products exporting, tolerance, and cellular regulation. In this article, we critically reviewed recent progresses and universal strategies in cyanobacterial chassis engineering to make it more robust and effective for bio-chemicals production.

New Vistas in Chemical Product and Process Design.

PubMed

Zhang, Lei; Babi, Deenesh K; Gani, Rafiqul

2016-06-07

Design of chemicals-based products is broadly classified into those that are process centered and those that are product centered. In this article, the designs of both classes of products are reviewed from a process systems point of view; developments related to the design of the chemical product, its corresponding process, and its integration are highlighted. Although significant advances have been made in the development of systematic model-based techniques for process design (also for optimization, operation, and control), much work is needed to reach the same level for product design. Timeline diagrams illustrating key contributions in product design, process design, and integrated product-process design are presented. The search for novel, innovative, and sustainable solutions must be matched by consideration of issues related to the multidisciplinary nature of problems, the lack of data needed for model development, solution strategies that incorporate multiscale options, and reliability versus predictive power. The need for an integrated model-experiment-based design approach is discussed together with benefits of employing a systematic computer-aided framework with built-in design templates.

Valorization of industrial waste and by-product streams via fermentation for the production of chemicals and biopolymers.

PubMed

Koutinas, Apostolis A; Vlysidis, Anestis; Pleissner, Daniel; Kopsahelis, Nikolaos; Lopez Garcia, Isabel; Kookos, Ioannis K; Papanikolaou, Seraphim; Kwan, Tsz Him; Lin, Carol Sze Ki

2014-04-21

The transition from a fossil fuel-based economy to a bio-based economy necessitates the exploitation of synergies, scientific innovations and breakthroughs, and step changes in the infrastructure of chemical industry. Sustainable production of chemicals and biopolymers should be dependent entirely on renewable carbon. White biotechnology could provide the necessary tools for the evolution of microbial bioconversion into a key unit operation in future biorefineries. Waste and by-product streams from existing industrial sectors (e.g., food industry, pulp and paper industry, biodiesel and bioethanol production) could be used as renewable resources for both biorefinery development and production of nutrient-complete fermentation feedstocks. This review focuses on the potential of utilizing waste and by-product streams from current industrial activities for the production of chemicals and biopolymers via microbial bioconversion. The first part of this review presents the current status and prospects on fermentative production of important platform chemicals (i.e., selected C2-C6 metabolic products and single cell oil) and biopolymers (i.e., polyhydroxyalkanoates and bacterial cellulose). In the second part, the qualitative and quantitative characteristics of waste and by-product streams from existing industrial sectors are presented. In the third part, the techno-economic aspects of bioconversion processes are critically reviewed. Four case studies showing the potential of case-specific waste and by-product streams for the production of succinic acid and polyhydroxyalkanoates are presented. It is evident that fermentative production of chemicals and biopolymers via refining of waste and by-product streams is a highly important research area with significant prospects for industrial applications.

Metabolic engineering of Corynebacterium glutamicum for fermentative production of chemicals in biorefinery.

PubMed

Baritugo, Kei-Anne; Kim, Hee Taek; David, Yokimiko; Choi, Jong-Il; Hong, Soon Ho; Jeong, Ki Jun; Choi, Jong Hyun; Joo, Jeong Chan; Park, Si Jae

2018-05-01

Bio-based production of industrially important chemicals provides an eco-friendly alternative to current petrochemical-based processes. Because of the limited supply of fossil fuel reserves, various technologies utilizing microbial host strains for the sustainable production of platform chemicals from renewable biomass have been developed. Corynebacterium glutamicum is a non-pathogenic industrial microbial species traditionally used for L-glutamate and L-lysine production. It is a promising species for industrial production of bio-based chemicals because of its flexible metabolism that allows the utilization of a broad spectrum of carbon sources and the production of various amino acids. Classical breeding, systems, synthetic biology, and metabolic engineering approaches have been used to improve its applications, ranging from traditional amino-acid production to modern biorefinery systems for production of value-added platform chemicals. This review describes recent advances in the development of genetic engineering tools and techniques for the establishment and optimization of metabolic pathways for bio-based production of major C2-C6 platform chemicals using recombinant C. glutamicum.

Chemical variability and leaf damage among lychee varieties, host of the Sri Lanka weevil, Myllocerus undecimpustulatus undatus Marchall

USDA-ARS?s Scientific Manuscript database

Chemical Variability and leaf damages among lychee varieties, host of the Sri Lanka weevil Myllocerus undecimpustulatus undatus Marshall. Jerome Niogret, Nancy Epsky, Paul Kendra, Peter Teal The Sri Lanka weevil Myllocerus undercimpustulatus undatus Marshall is serious economic pest in India and P...

Chemical proteomics approaches for identifying the cellular targets of natural products

PubMed Central

Sieber, S. A.

2016-01-01

Covering: 2010 up to 2016 Deconvoluting the mode of action of natural products and drugs remains one of the biggest challenges in chemistry and biology today. Chemical proteomics is a growing area of chemical biology that seeks to design small molecule probes to understand protein function. In the context of natural products, chemical proteomics can be used to identify the protein binding partners or targets of small molecules in live cells. Here, we highlight recent examples of chemical probes based on natural products and their application for target identification. The review focuses on probes that can be covalently linked to their target proteins (either via intrinsic chemical reactivity or via the introduction of photocrosslinkers), and can be applied “in situ” – in living systems rather than cell lysates. We also focus here on strategies that employ a click reaction, the copper-catalysed azide–alkyne cycloaddition reaction (CuAAC), to allow minimal functionalisation of natural product scaffolds with an alkyne or azide tag. We also discuss ‘competitive mode’ approaches that screen for natural products that compete with a well-characterised chemical probe for binding to a particular set of protein targets. Fuelled by advances in mass spectrometry instrumentation and bioinformatics, many modern strategies are now embracing quantitative proteomics to help define the true interacting partners of probes, and we highlight the opportunities this rapidly evolving technology provides in chemical proteomics. Finally, some of the limitations and challenges of chemical proteomics approaches are discussed. PMID:27098809

Chemical proteomics approaches for identifying the cellular targets of natural products.

PubMed

Wright, M H; Sieber, S A

2016-05-04

Covering: 2010 up to 2016Deconvoluting the mode of action of natural products and drugs remains one of the biggest challenges in chemistry and biology today. Chemical proteomics is a growing area of chemical biology that seeks to design small molecule probes to understand protein function. In the context of natural products, chemical proteomics can be used to identify the protein binding partners or targets of small molecules in live cells. Here, we highlight recent examples of chemical probes based on natural products and their application for target identification. The review focuses on probes that can be covalently linked to their target proteins (either via intrinsic chemical reactivity or via the introduction of photocrosslinkers), and can be applied "in situ" - in living systems rather than cell lysates. We also focus here on strategies that employ a click reaction, the copper-catalysed azide-alkyne cycloaddition reaction (CuAAC), to allow minimal functionalisation of natural product scaffolds with an alkyne or azide tag. We also discuss 'competitive mode' approaches that screen for natural products that compete with a well-characterised chemical probe for binding to a particular set of protein targets. Fuelled by advances in mass spectrometry instrumentation and bioinformatics, many modern strategies are now embracing quantitative proteomics to help define the true interacting partners of probes, and we highlight the opportunities this rapidly evolving technology provides in chemical proteomics. Finally, some of the limitations and challenges of chemical proteomics approaches are discussed.

Characterization and Prediction of Chemical Functions and Weight Fractions in Consumer Products

EPA Science Inventory

Assessing exposures from the thousands of chemicals in commerce requires quantitative information on the chemical constituents of consumer products. Unfortunately, gaps in available composition data prevent assessment of exposure to chemicals in many products. Here we propose fil...

Leveraging Publicly-Available Consumer Product and Chemical Data in Support of Exposure Modeling

EPA Science Inventory

Near-field contact with chemicals in consumer products has been identified as a significant source of human exposure. To predict such exposures, information about chemical occurrence in consumer products is required, but is often not available. The Chemicals and Products Database...

Moisture Damage Modeling in Lime and Chemically Modified Asphalt at Nanolevel Using Ensemble Computational Intelligence

PubMed Central

2018-01-01

This paper measures the adhesion/cohesion force among asphalt molecules at nanoscale level using an Atomic Force Microscopy (AFM) and models the moisture damage by applying state-of-the-art Computational Intelligence (CI) techniques (e.g., artificial neural network (ANN), support vector regression (SVR), and an Adaptive Neuro Fuzzy Inference System (ANFIS)). Various combinations of lime and chemicals as well as dry and wet environments are used to produce different asphalt samples. The parameters that were varied to generate different asphalt samples and measure the corresponding adhesion/cohesion forces are percentage of antistripping agents (e.g., Lime and Unichem), AFM tips K values, and AFM tip types. The CI methods are trained to model the adhesion/cohesion forces given the variation in values of the above parameters. To achieve enhanced performance, the statistical methods such as average, weighted average, and regression of the outputs generated by the CI techniques are used. The experimental results show that, of the three individual CI methods, ANN can model moisture damage to lime- and chemically modified asphalt better than the other two CI techniques for both wet and dry conditions. Moreover, the ensemble of CI along with statistical measurement provides better accuracy than any of the individual CI techniques. PMID:29849551

Retail sales of scheduled listed chemical products; self-certification of regulated sellers of scheduled listed chemical products. Interim final rule with request for comment.

PubMed

2006-09-26

In March 2006, the President signed the Combat Methamphetamine Epidemic Act of 2005, which establishes new requirements for retail sales of over-the-counter (nonprescription) products containing the List I chemicals ephedrine, pseudoephedrine, and phenylpropanolamine. The three chemicals can be used to manufacture methamphetamine illegally. DEA is promulgating this rule to incorporate the statutory provisions and make its regulations consistent with the new requirements. This action establishes daily and 30-day limits on the sales of scheduled listed chemical products to individuals and requires recordkeeping on most sales.

Patterns of poststroke brain damage that predict speech production errors in apraxia of speech and aphasia dissociate.

PubMed

Basilakos, Alexandra; Rorden, Chris; Bonilha, Leonardo; Moser, Dana; Fridriksson, Julius

2015-06-01

Acquired apraxia of speech (AOS) is a motor speech disorder caused by brain damage. AOS often co-occurs with aphasia, a language disorder in which patients may also demonstrate speech production errors. The overlap of speech production deficits in both disorders has raised questions on whether AOS emerges from a unique pattern of brain damage or as a subelement of the aphasic syndrome. The purpose of this study was to determine whether speech production errors in AOS and aphasia are associated with distinctive patterns of brain injury. Forty-three patients with history of a single left-hemisphere stroke underwent comprehensive speech and language testing. The AOS Rating Scale was used to rate speech errors specific to AOS versus speech errors that can also be associated with both AOS and aphasia. Localized brain damage was identified using structural magnetic resonance imaging, and voxel-based lesion-impairment mapping was used to evaluate the relationship between speech errors specific to AOS, those that can occur in AOS or aphasia, and brain damage. The pattern of brain damage associated with AOS was most strongly associated with damage to cortical motor regions, with additional involvement of somatosensory areas. Speech production deficits that could be attributed to AOS or aphasia were associated with damage to the temporal lobe and the inferior precentral frontal regions. AOS likely occurs in conjunction with aphasia because of the proximity of the brain areas supporting speech and language, but the neurobiological substrate for each disorder differs. © 2015 American Heart Association, Inc.

Estimating Cone and Seed Production and Monitoring Pest Damage in Southern Pine Seed Orchards

Treesearch

Carl W. Fatzinger; H. David Muse; Thomas Miller; Helen T. Bhattacharyya

1988-01-01

Field sampling procedures and computer programs are described for monitoring seed production and pest damage in southern pine seed orchards. The system estimates total orchard yields of female strobili and seeds, quantifies pest damage, determines times of year when losses occur, and produces life tables for female strobili. An example is included to illustrate the...

Human exposure modeling in a life cycle framework for chemicals and products

EPA Science Inventory

A chemical enters into commerce to serve a specific function in a product or process. This decision triggers both the manufacture of the chemical and its potential release over the life cycle of the product. Efficiently evaluating chemical safety and sustainability requires combi...

In situ FTIR microspectroscopy of extravasated blood-damaged brain tissue

NASA Astrophysics Data System (ADS)

Wetzel, David L.; Le Vine, Steven M.

1994-01-01

Fourier transform infrared (FT-IR) microspectroscopy enables the collection of infrared spectra from microscopic regions of tissue sections. The objectives of this study were to utilize FT-IR microspectroscopy to analyze the spatial distribution of chemical changes that result from the extravasation of blood into the brain and to determine if products of free radical damage are associated with the damaged areas. An animal model that involves the injection of blood into the white matter of rat brains was used. Maps depicting the relative concentrations of chemical functional groups of lesioned sites and surrounding areas were made. Significant decreases were observed for CH2, C equals O, P equals O, and HO-C-H functional groups at the lesioned site and penumbra regions compared to the neighboring normal tissue areas.

Why Leading Consumer Product Companies Develop Proactive Chemical Management Strategies.

PubMed

Scruggs, Caroline E; Van Buren, Harry J

2016-05-01

Scholars have studied the various pressures that companies face related to socially responsible behavior when stakeholders know the particular social issues under consideration. Many have examined social responsibility in the context of environmental responsibility and the general approaches companies take regarding environmental management. The issue of currently unregulated, but potentially hazardous, chemicals in consumer products is not well understood by the general public, but a number of proactive consumer product companies have voluntarily adopted strategies to minimize use of such chemicals. These companies are exceeding regulatory requirements by restricting from their products chemicals that could harm human or environmental health, despite the fact that these actions are costly. They do not usually advertise the details of their strategies to end consumers. This article uses interviews with senior environmental directors of 20 multinational consumer product companies to investigate why these companies engage in voluntary chemicals management. The authors conclude that the most significant reasons are to achieve a competitive advantage and stay ahead of regulations, manage relationships and maintain legitimacy with stakeholders, and put managerial values into practice. Many of the characteristics related to the case of chemicals management are extendable to other areas of stakeholder management in which risks to stakeholders are either unknown or poorly understood.

Why Leading Consumer Product Companies Develop Proactive Chemical Management Strategies

PubMed Central

Scruggs, Caroline E.; Van Buren, Harry J.

2014-01-01

Scholars have studied the various pressures that companies face related to socially responsible behavior when stakeholders know the particular social issues under consideration. Many have examined social responsibility in the context of environmental responsibility and the general approaches companies take regarding environmental management. The issue of currently unregulated, but potentially hazardous, chemicals in consumer products is not well understood by the general public, but a number of proactive consumer product companies have voluntarily adopted strategies to minimize use of such chemicals. These companies are exceeding regulatory requirements by restricting from their products chemicals that could harm human or environmental health, despite the fact that these actions are costly. They do not usually advertise the details of their strategies to end consumers. This article uses interviews with senior environmental directors of 20 multinational consumer product companies to investigate why these companies engage in voluntary chemicals management. The authors conclude that the most significant reasons are to achieve a competitive advantage and stay ahead of regulations, manage relationships and maintain legitimacy with stakeholders, and put managerial values into practice. Many of the characteristics related to the case of chemicals management are extendable to other areas of stakeholder management in which risks to stakeholders are either unknown or poorly understood. PMID:27471326

Inherent health and environmental risk assessment of nanostructured metal oxide production processes.

PubMed

Torabifard, Mina; Arjmandi, Reza; Rashidi, Alimorad; Nouri, Jafar; Mohammadfam, Iraj

2018-01-10

The health and environmental effects of chemical processes can be assessed during the initial stage of their production. In this paper, the Chemical Screening Tool for Exposure and Environmental Release (ChemSTEER) software was used to compare the health and environmental risks of spray pyrolysis and wet chemical techniques for the fabrication of nanostructured metal oxide on a semi-industrial scale with a capacity of 300 kg/day in Iran. The pollution sources identified in each production process were pairwise compared in Expert Choice software using indicators including respiratory damage, skin damage, and environmental damages including air, water, and soil pollution. The synthesis of nanostructured zinc oxide using the wet chemical technique (with 0.523 wt%) leads to lower health and environmental risks compared to when spray pyrolysis is used (with 0.477 wt%). The health and environmental risk assessment of nanomaterial production processes can help select safer processes, modify the operation conditions, and select or modify raw materials that can help eliminate the risks.

Novel Chemical Space Exploration via Natural Products

PubMed Central

Rosén, Josefin; Gottfries, Johan; Muresan, Sorel; Backlund, Anders; Oprea, Tudor I.

2009-01-01

Natural products (NPs) are a rich source of novel compound classes and new drugs. In the present study we have used the chemical space navigation tool ChemGPS-NP to evaluate the chemical space occupancy by NPs and bioactive medicinal chemistry compounds from the database WOMBAT. The two sets differ notable in coverage of chemical space, and tangible lead-like NPs were found to cover regions of chemical space that lack representation in WOMBAT. Property based similarity calculations were performed to identify NP neighbours of approved drugs. Several of the NPs revealed by this method, were confirmed to exhibit the same activity as their drug neighbours. The identification of leads from a NP starting point may prove a useful strategy for drug discovery, in the search for novel leads with unique properties. PMID:19265440

High-throughput exposure modeling to support prioritization of chemicals in personal care products.

PubMed

Csiszar, Susan A; Ernstoff, Alexi S; Fantke, Peter; Meyer, David E; Jolliet, Olivier

2016-11-01

We demonstrate the application of a high-throughput modeling framework to estimate exposure to chemicals used in personal care products (PCPs). As a basis for estimating exposure, we use the product intake fraction (PiF), defined as the mass of chemical taken by an individual or population per mass of a given chemical used in a product. We calculated use- and disposal- stage PiFs for 518 chemicals for five PCP archetypes. Across all product archetypes the use- and disposal- stage PiFs ranged from 10(-5) to 1 and 0 to 10(-3), respectively. There is a distinction between the use-stage PiF for leave-on and wash-off products which had median PiFs of 0.5 and 0.02 across the 518 chemicals, respectively. The PiF is a function of product characteristics and physico-chemical properties and is maximized when skin permeability is high and volatility is low such that there is no competition between skin and air losses from the applied product. PCP chemical contents (i.e. concentrations) were available for 325 chemicals and were combined with PCP usage characteristics and PiF yielding intakes summed across a demonstrative set of products ranging from 10(-8)-30 mg/kg/d, with a median of 0.1 mg/kg/d. The highest intakes were associated with body lotion. Bioactive doses derived from high-throughput in vitro toxicity data were combined with the estimated PiFs to demonstrate an approach to estimate bioactive equivalent chemical content and to screen chemicals for risk. Copyright © 2016 Elsevier Ltd. All rights reserved.

Origins and consequences of DNA damage in male germ cells.

PubMed

Aitken, R John; De Iuliis, Geoffry N

2007-06-01

DNA damage in the male germline is associated with poor fertilization rates following IVF, defective preimplantation embryonic development, and high rates of miscarriage and morbidity in the offspring, including childhood cancer. This damage is poorly characterized, but is known to involve hypomethylation of key genes, oxidative base damage, endonuclease-mediated cleavage and the formation of adducts with xenobiotics and the products of lipid peroxidation. There are many possible causes of such DNA damage, including abortive apoptosis, the oxidative stress associated with male genital tract infection, exposure to redox cycling chemicals, and defects of spermiogenesis associated with the retention of excess residual cytoplasm. Physical factors such as exposure to radiofrequency electromagnetic radiation or mild scrotal heating can also induce DNA damage in mammalian spermatozoa, although the underlying mechanisms are unclear. Ultimately, resolving the precise nature of the DNA lesions present in the spermatozoa of infertile men will be an important step towards uncovering the aetiology of this damage and developing strategies for its clinical management.

Chemical state of fission products in irradiated uranium carbide fuel

NASA Astrophysics Data System (ADS)

Arai, Yasuo; Iwai, Takashi; Ohmichi, Toshihiko

1987-12-01

The chemical state of fission products in irradiated uranium carbide fuel has been estimated by equilibrium calculation using the SOLGASMIX-PV program. Solid state fission products are distributed to the fuel matrix, ternary compounds, carbides of fission products and intermetallic compounds among the condensed phases appearing in the irradiated uranium carbide fuel. The chemical forms are influenced by burnup as well as stoichiometry of the fuel. The results of the present study almost agree with the experimental ones reported for burnup simulated carbides.

Effects of soft X-ray radiation damage on paraffin-embedded rat tissues supported on ultralene: a chemical perspective.

PubMed

Bedolla, Diana E; Mantuano, Andrea; Pickler, Arissa; Mota, Carla Lemos; Braz, Delson; Salata, Camila; Almeida, Carlos Eduardo; Birarda, Giovanni; Vaccari, Lisa; Barroso, Regina Cély; Gianoncelli, Alessandra

2018-05-01

Radiation damage is an important aspect to be considered when analysing biological samples with X-ray techniques as it can induce chemical and structural changes in the specimens. This work aims to provide new insights into the soft X-ray induced radiation damage of the complete sample, including not only the biological tissue itself but also the substrate and embedding medium, and the tissue fixation procedure. Sample preparation and handling involves an unavoidable interaction with the sample matrix and could play an important role in the radiation-damage mechanism. To understand the influence of sample preparation and handling on radiation damage, the effects of soft X-ray exposure at different doses on ultralene, paraffin and on paraffin-embedded rat tissues were studied using Fourier-transform infrared (FTIR) microspectroscopy and X-ray microscopy. Tissues were preserved with three different commonly used fixatives: formalin, glutaraldehyde and Karnovsky. FTIR results showed that ultralene and paraffin undergo a dose-dependent degradation of their vibrational profiles, consistent with radiation-induced oxidative damage. In addition, formalin fixative has been shown to improve the preservation of the secondary structure of proteins in tissues compared with both glutaraldehyde and Karnovsky fixation. However, conclusive considerations cannot be drawn on the optimal fixation protocol because of the interference introduced by both substrate and embedding medium in the spectral regions specific to tissue lipids, nucleic acids and carbohydrates. Notably, despite the detected alterations affecting the chemical architecture of the sample as a whole, composed of tissue, substrate and embedding medium, the structural morphology of the tissues at the micrometre scale is essentially preserved even at the highest exposure dose.

Physical and Chemical Microstructural Damage in Pressed CL-20 explosives

NASA Astrophysics Data System (ADS)

Demol, Gauthier; Sandusky, Harold W.

1999-06-01

Based upon its molecular composition, its structure, and its heat of formation, it was expected that CL-20 (hexanitrohexaazaisowurtzitane) would be more energetic and more sensitive than RDX and HMX. Reports of batch-to-batch variations in the sensitivity of neat CL-20 have led to its sensitivity being ranked in the range between the sensitivity of RDX and that of PETN. The ultimate utility of CL-20 as an ingredient in explosive and propellant formulations will depend upon the ability to understand the factors that are responsible for this batch-to-batch variability, and to control the sensitivity in formulations within acceptable limits. This work is a characterization of CL-20 at various stages in its life cycle. The evolution of damage from the initial neat crystals of CL-20 to the ready-to-use pressed pellets will be described. This characterization includes physical documentation using light microscopy and Scanning Electron Microscopy. Spatially resolved chemical analysis is also performed using Fourier-Transform Infrared Spectroscopy.

Molecular dynamics simulations of damage production by thermal spikes in Ge

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lopez, Pedro; Pelaz, Lourdes; Santos, Ivan

2012-02-01

Molecular dynamics simulation techniques are used to analyze damage production in Ge by the thermal spike process and to compare the results to those obtained for Si. As simulation results are sensitive to the choice of the inter-atomic potential, several potentials are compared in terms of material properties relevant for damage generation, and the most suitable potentials for this kind of analysis are identified. A simplified simulation scheme is used to characterize, in a controlled way, the damage generation through the local melting of regions in which energy is deposited. Our results show the outstanding role of thermal spikes inmore » Ge, since the lower melting temperature and thermal conductivity of Ge make this process much more efficient in terms of damage generation than in Si. The study is extended to the modeling of full implant cascades, in which both collision events and thermal spikes coexist. Our simulations reveal the existence of bigger damaged or amorphous regions in Ge than in Si, which may be formed by the melting and successive quenching induced by thermal spikes. In the particular case of heavy ion implantation, defect structures in Ge are not only bigger, but they also present a larger net content in vacancies than in Si, which may act as precursors for the growth of voids and the subsequent formation of honeycomb-like structures.« less

Exploring Exposure Pathways with Chemical/Product Categorical CPCat)Data

EPA Science Inventory

Humans are exposed to thousands of chemicals over our lifetimes. A major challenge to risk assessors is to understand how and when chemical exposures occur, and which “exposure pathways” contribute the most. An informatics-driven approach to assigning “product-use” categories to ...

EFFECTS OF ENVIRONMENTAL CHEMICALS ON FETAL TESTES TESTOSTERONE PRODUCTION

EPA Science Inventory

Effects of Environmental Chemicals on Fetal Testes Testosterone Production

Lambright, CS , Wilson, VS , Furr, J, Wolf, CJ, Noriega, N, Gray, LE, Jr.
US EPA, ORD/NHEERL/RTD, RTP, NC

Exposure of pregnant rodents to certain environmental chemicals during criti...

Unit Price Scaling Trends for Chemical Products

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qi, Wei; Sathre, Roger; William R. Morrow, III

2015-08-01

To facilitate early-stage life-cycle techno-economic modeling of emerging technologies, here we identify scaling relations between unit price and sales quantity for a variety of chemical products of three categories - metal salts, organic compounds, and solvents. We collect price quotations for lab-scale and bulk purchases of chemicals from both U.S. and Chinese suppliers. We apply a log-log linear regression model to estimate the price discount effect. Using the median discount factor of each category, one can infer bulk prices of products for which only lab-scale prices are available. We conduct out-of-sample tests showing that most of the price proxies deviatemore » from their actual reference prices by a factor less than ten. We also apply the bootstrap method to determine if a sample median discount factor should be accepted for price approximation. We find that appropriate discount factors for metal salts and for solvents are both -0.56, while that for organic compounds is -0.67 and is less representative due to greater extent of product heterogeneity within this category.« less

Metabolite damage and repair in metabolic engineering design.

PubMed

Sun, Jiayi; Jeffryes, James G; Henry, Christopher S; Bruner, Steven D; Hanson, Andrew D

2017-11-01

The necessarily sharp focus of metabolic engineering and metabolic synthetic biology on pathways and their fluxes has tended to divert attention from the damaging enzymatic and chemical side-reactions that pathway metabolites can undergo. Although historically overlooked and underappreciated, such metabolite damage reactions are now known to occur throughout metabolism and to generate (formerly enigmatic) peaks detected in metabolomics datasets. It is also now known that metabolite damage is often countered by dedicated repair enzymes that undo or prevent it. Metabolite damage and repair are highly relevant to engineered pathway design: metabolite damage reactions can reduce flux rates and product yields, and repair enzymes can provide robust, host-independent solutions. Herein, after introducing the core principles of metabolite damage and repair, we use case histories to document how damage and repair processes affect efficient operation of engineered pathways - particularly those that are heterologous, non-natural, or cell-free. We then review how metabolite damage reactions can be predicted, how repair reactions can be prospected, and how metabolite damage and repair can be built into genome-scale metabolic models. Lastly, we propose a versatile 'plug and play' set of well-characterized metabolite repair enzymes to solve metabolite damage problems known or likely to occur in metabolic engineering and synthetic biology projects. Copyright © 2017 International Metabolic Engineering Society. All rights reserved.

Metabolite damage and repair in metabolic engineering design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Jiayi; Jeffryes, James G.; Henry, Christopher S.

The necessarily sharp focus of metabolic engineering and metabolic synthetic biology on pathways and their fluxes has tended to divert attention from the damaging enzymatic and chemical side-reactions that pathway metabolites can undergo. Although historically overlooked and underappreciated, such metabolite damage reactions are now known to occur throughout metabolism and to generate (formerly enigmatic) peaks detected in metabolomics datasets. It is also now known that metabolite damage is often countered by dedicated repair enzymes that undo or prevent it. Metabolite damage and repair are highly relevant to engineered pathway design: metabolite damage reactions can reduce flux rates and product yields,more » and repair enzymes can provide robust, host-independent solutions. Herein, after introducing the core principles of metabolite damage and repair, we use case histories to document how damage and repair processes affect efficient operation of engineered pathways - particularly those that are heterologous, non-natural, or cell-free. We then review how metabolite damage reactions can be predicted, how repair reactions can be prospected, and how metabolite damage and repair can be built into genome-scale metabolic models. Lastly, we propose a versatile 'plug and play' set of well-characterized metabolite repair enzymes to solve metabolite damage problems known or likely to occur in metabolic engineering and synthetic biology projects.« less

Patterns of Post-Stroke Brain Damage that Predict Speech Production Errors in Apraxia of Speech and Aphasia Dissociate

PubMed Central

Basilakos, Alexandra; Rorden, Chris; Bonilha, Leonardo; Moser, Dana; Fridriksson, Julius

2015-01-01

Background and Purpose Acquired apraxia of speech (AOS) is a motor speech disorder caused by brain damage. AOS often co-occurs with aphasia, a language disorder in which patients may also demonstrate speech production errors. The overlap of speech production deficits in both disorders has raised questions regarding if AOS emerges from a unique pattern of brain damage or as a sub-element of the aphasic syndrome. The purpose of this study was to determine whether speech production errors in AOS and aphasia are associated with distinctive patterns of brain injury. Methods Forty-three patients with history of a single left-hemisphere stroke underwent comprehensive speech and language testing. The Apraxia of Speech Rating Scale was used to rate speech errors specific to AOS versus speech errors that can also be associated with AOS and/or aphasia. Localized brain damage was identified using structural MRI, and voxel-based lesion-impairment mapping was used to evaluate the relationship between speech errors specific to AOS, those that can occur in AOS and/or aphasia, and brain damage. Results The pattern of brain damage associated with AOS was most strongly associated with damage to cortical motor regions, with additional involvement of somatosensory areas. Speech production deficits that could be attributed to AOS and/or aphasia were associated with damage to the temporal lobe and the inferior pre-central frontal regions. Conclusion AOS likely occurs in conjunction with aphasia due to the proximity of the brain areas supporting speech and language, but the neurobiological substrate for each disorder differs. PMID:25908457

Chemical production in electrocautery smoke by a novel predictive model.

PubMed

Wu, Y-C; Tang, C-S; Huang, H-Y; Liu, C-H; Chen, Y-L; Chen, D-R; Lin, Y-W

2011-01-01

The hazards of electrocautery smoke have been known for decades. However, few clinical studies have been conducted to analyze the responsible variables of the smoke production. This study collected clinical smoke samples and systematically analyzed all possible factors. Thirty diathermy smoke samples were collected during mastectomy and abdominal cavity operations. Samples were analyzed using a gas chromatographer with a flame ionization detector. Data were applied to construct prediction models for chemical production from electrosurgeries to identify all possible factors that impact chemical production during electrosurgery. Toluene was detected in 27 smoke samples (90%) with concentrations of 0.003-0.463 mg/m(3) and production of 176.0-2,780.0 ng. Ethyl benzene and styrene were identified in very few cases. General linear regression analysis demonstrates that surgery type, patient age, electrocautery duration and imparted coagulation energy explained 67.63% of the variation in toluene production. Surgery type and patient age are known prior to surgery. In terms of risk precaution, the operating team should pay close attention to exposure when certain positive factors of increasing the chemical production are known in advance. Copyright © 2011 S. Karger AG, Basel.

Selecting the Best: Evolutionary Engineering of Chemical Production in Microbes.

PubMed

Shepelin, Denis; Hansen, Anne Sofie Lærke; Lennen, Rebecca; Luo, Hao; Herrgård, Markus J

2018-05-11

Microbial cell factories have proven to be an economical means of production for many bulk, specialty, and fine chemical products. However, we still lack both a holistic understanding of organism physiology and the ability to predictively tune enzyme activities in vivo, thus slowing down rational engineering of industrially relevant strains. An alternative concept to rational engineering is to use evolution as the driving force to select for desired changes, an approach often described as evolutionary engineering. In evolutionary engineering, in vivo selections for a desired phenotype are combined with either generation of spontaneous mutations or some form of targeted or random mutagenesis. Evolutionary engineering has been used to successfully engineer easily selectable phenotypes, such as utilization of a suboptimal nutrient source or tolerance to inhibitory substrates or products. In this review, we focus primarily on a more challenging problem-the use of evolutionary engineering for improving the production of chemicals in microbes directly. We describe recent developments in evolutionary engineering strategies, in general, and discuss, in detail, case studies where production of a chemical has been successfully achieved through evolutionary engineering by coupling production to cellular growth.

Data on the chemical properties of commercial fish sauce products.

PubMed

Nakano, Mitsutoshi; Sagane, Yoshimasa; Koizumi, Ryosuke; Nakazawa, Yozo; Yamazaki, Masao; Watanabe, Toshihiro; Takano, Katsumi; Sato, Hiroaki

2017-12-01

This data article reports on the chemical properties of commercial fish sauce products associated with the fish sauce taste and flavor. All products were analyzed in triplicate. Dried solid content was analyzed by moisture analyzer. Fish sauce salinity was determined by a salt meter. pH was measured using a pH meter. The acidity was determined using a titration assay. Amino nitrogen and total nitrogen were evaluated using a titration assay and Combustion-type nitrogen analyzer, respectively. The analyzed products originated from Japan, Thailand, Vietnam, China, the Philippines, and Italy. Data on the chemical properties of the products are provided in table format in the current article.

Engineering biocatalysts for production of commodity chemicals.

PubMed

Shanmugam, K T; Ingram, L O

2008-01-01

Lignocellulosic biomass is an attractive alternate to petroleum for production of both fuels and commodity chemicals. This conversion of biomass would require a new generation of microbial biocatalysts that can convert all the sugars present in the biomass to the desired compounds. In this review, the critical factors that need to be considered in engineering such microbial biocatalysts for cost-effective fermentation of sugars are discussed with specific emphasis on commodity chemicals such as lactic acid, succinic acid and acetic acid. (c) 2008 S. Karger AG, Basel

Exposures to Endocrine Disrupting Chemicals in Consumer Products-A Guide for Pediatricians.

PubMed

Wong, Katelyn H; Durrani, Timur S

2017-05-01

Endocrine disrupting chemicals, a group of exogenous chemicals that can interfere with hormone action in the body, have been implicated in disrupting endocrine function, which negatively affects human health and development. Endocrine disrupting chemicals are ubiquitously detected in consumer products, foods, beverages, personal care products, and household cleaning products. Due to concerns about their negative effects on human health, several professional health provider societies have recommended the reduction of common endocrine disrupting chemical exposures. The purpose of this review is to provide a brief overview of common endocrine disrupting chemicals (bisphenol A, phthalates, triclosan, polybrominated ethers, and parabens) and potential effects on child development and health. In addition, we aim to provide guidance and resources for pediatricians and other health care providers with counseling strategies to help patients to minimize exposures to common endocrine disrupting chemicals. Copyright © 2017 Mosby, Inc. All rights reserved.

21 CFR 1310.16 - Exemptions for certain scheduled listed chemical products.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 9 2011-04-01 2011-04-01 false Exemptions for certain scheduled listed chemical... RECORDS AND REPORTS OF LISTED CHEMICALS AND CERTAIN MACHINES § 1310.16 Exemptions for certain scheduled listed chemical products. (a) Upon the application of a manufacturer of a scheduled listed chemical...

Development of a Consumer Product Ingredient Database for Chemical ExposureScreening and Prioritization

EPA Science Inventory

Consumer products are a primary source of chemical exposures, yet little structured information is available on the chemical ingredients of these products and the concentrations at which ingredients are present. To address this data gap, we created a database of chemicals in cons...

Measurements of in situ chemical ozone (oxidant) production rates

NASA Astrophysics Data System (ADS)

Huang, Hao; Faloon, Kate; Najera, Juan; Bloss, William

2013-04-01

Tropospheric ozone is a major air pollutant, harmful to human health, agricultural crops and vegetation, the main precursor to the atmospheric oxidants which initiate the degradation of most reactive gases emitted to the atmosphere, and an important greenhouse gas in its own right. The capacity to understand and predict tropospheric ozone levels is a key goal for atmospheric science - but one which is challenging, as ozone is formed in the atmosphere from the complex oxidation of VOCs in the presence of NOx and sunlight, on a timescale such that in situ chemical processes, deposition and transport all affect ozone levels. Known uncertainties in emissions, chemistry, dynamics and deposition affect the accuracy of predictions of current and future ozone levels, and hinder development of optimal air quality policies to mitigate against ozone exposure. Recently new approaches to directly measure the local chemical ozone production rate, bypassing the many uncertainties in emissions and chemical schemes, have been developed (Cazorla & Brune, AMT 2010). Here, we describe the development of an analogous Ozone Production Rate (OPR) approach: Air is sampled into parallel reactors, within which ozone formation either occurs as in the ambient atmosphere, or is suppressed. Comparisons of ozone levels exiting a pair of such reactors determines the net chemical oxidant production rate, after correction for perturbation of the NOx-O3 photochemical steady state, and when operated under conditions such that wall effects are minimised. We report preliminary measurements of local chemical ozone production made during the UK NERC ClearfLo (Clean Air for London) campaign at an urban background location in London in January and July 2012. The OPR system was used to measure the local chemical oxidant formation rate, which is compared with observed trends in O3 and NOx and the prevailing meteorology, and with the predictions of a detailed zero-dimensional atmospheric chemistry model

Production of Fatty Acid-Derived Valuable Chemicals in Synthetic Microbes

PubMed Central

Yu, Ai-Qun; Pratomo Juwono, Nina Kurniasih; Leong, Susanna Su Jan; Chang, Matthew Wook

2014-01-01

Fatty acid derivatives, such as hydroxy fatty acids, fatty alcohols, fatty acid methyl/ethyl esters, and fatty alka(e)nes, have a wide range of industrial applications including plastics, lubricants, and fuels. Currently, these chemicals are obtained mainly through chemical synthesis, which is complex and costly, and their availability from natural biological sources is extremely limited. Metabolic engineering of microorganisms has provided a platform for effective production of these valuable biochemicals. Notably, synthetic biology-based metabolic engineering strategies have been extensively applied to refactor microorganisms for improved biochemical production. Here, we reviewed: (i) the current status of metabolic engineering of microbes that produce fatty acid-derived valuable chemicals, and (ii) the recent progress of synthetic biology approaches that assist metabolic engineering, such as mRNA secondary structure engineering, sensor-regulator system, regulatable expression system, ultrasensitive input/output control system, and computer science-based design of complex gene circuits. Furthermore, key challenges and strategies were discussed. Finally, we concluded that synthetic biology provides useful metabolic engineering strategies for economically viable production of fatty acid-derived valuable chemicals in engineered microbes. PMID:25566540

Myoprotective Potential of Creatine Is Greater than Whey Protein after Chemically-Induced Damage in Rat Skeletal Muscle

PubMed Central

Cooke, Matthew B.; Stathis, Christos G.; Hayes, Alan

2018-01-01

The myoprotective effects of creatine monohydrate (CR) and whey protein (WP) are equivocal, with the use of proxy measures of muscle damage making interpretation of their effectiveness limited. The purpose of the study was to determine the effects of CR and WP supplementation on muscle damage and recovery following controlled, chemically-induced muscle damage. Degeneration of the extensor digitorum longus (EDL) muscle was induced by bupivacaine in rats supplemented with either CR, WP, or standard rat chow (CON). At day 7 and 14 post-myotoxic injury, injured EDL muscles were surgically removed and tested for isometric contractile properties, followed by the contralateral, non-injured EDL muscle. At the completion of testing, muscles were snap-frozen in liquid nitrogen and stored for later analysis. Data were analyzed using analysis of variance. Creatine-supplemented muscles displayed a greater proportion of non-damaged (intact) fibers (p = 0.002) and larger cross-sectional areas of regenerating and non-damaged fibers (p = 0.024) compared to CON muscles at day 7 post-injury. At day 14 post-injury, CR-supplemented muscles generated higher absolute forces concomitant with greater contractile protein levels compared to CON (p = 0.001, p = 0.008) and WP-supplemented muscles (p = 0.003, p = 0.006). Creatine supplementation appears to offer an element of myoprotection which was not observed following whey protein supplementation. PMID:29710855

Coupled near-field and far-field exposure assessment framework for chemicals in consumer products.

PubMed

Fantke, Peter; Ernstoff, Alexi S; Huang, Lei; Csiszar, Susan A; Jolliet, Olivier

2016-09-01

Humans can be exposed to chemicals in consumer products through product use and environmental emissions over the product life cycle. Exposure pathways are often complex, where chemicals can transfer directly from products to humans during use or exchange between various indoor and outdoor compartments until sub-fractions reach humans. To consistently evaluate exposure pathways along product life cycles, a flexible mass balance-based assessment framework is presented structuring multimedia chemical transfers in a matrix of direct inter-compartmental transfer fractions. By matrix inversion, we quantify cumulative multimedia transfer fractions and exposure pathway-specific product intake fractions defined as chemical mass taken in by humans per unit mass of chemical in a product. Combining product intake fractions with chemical mass in the product yields intake estimates for use in life cycle impact assessment and chemical alternatives assessment, or daily intake doses for use in risk-based assessment and high-throughput screening. Two illustrative examples of chemicals used in personal care products and flooring materials demonstrate how this matrix-based framework offers a consistent and efficient way to rapidly compare exposure pathways for adult and child users and for the general population. This framework constitutes a user-friendly approach to develop, compare and interpret multiple human exposure scenarios in a coupled system of near-field ('user' environment), far-field and human intake compartments, and helps understand the contribution of individual pathways to overall human exposure in various product application contexts to inform decisions in different science-policy fields for which exposure quantification is relevant. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Temperature dependence on plasma-induced damage and chemical reactions in GaN etching processes using chlorine plasma

NASA Astrophysics Data System (ADS)

Liu, Zecheng; Ishikawa, Kenji; Imamura, Masato; Tsutsumi, Takayoshi; Kondo, Hiroki; Oda, Osamu; Sekine, Makoto; Hori, Masaru

2018-06-01

Plasma-induced damage (PID) on GaN was optimally reduced by high-temperature chlorine plasma etching. Energetic ion bombardments primarily induced PID involving stoichiometry, surface roughness, and photoluminescence (PL) degradation. Chemical reactions under ultraviolet (UV) irradiation and chlorine radical exposure at temperatures higher than 400 °C can be controlled by taking into account the synergism of simultaneous photon and radical irradiations to effectively reduce PID.

Phytohormone ecology : Herbivory byThrips tabaci induces greater ethylene production in intact onions than mechanical damage alone.

PubMed

Kendall, D M; Bjostad, L B

1990-03-01

Herbivory byThrips tabaci affected production of the phytohormone ethylene from living onion foliage. Ethylene analysis was performed by gas chromatography on intact onion tissue. Thrips feeding damage and a crushed thrips extract stimulated significantly greater production of eihylene than could be explained by either one-time or semicontinuous mechanical damage alone, suggesting that ethylene-inducing cues may be transferred to the plant during feeding. This is the first demonstration of increased ethylene production from insect-infested intact plants. This study suggests that herbivores affect both the phytohormone physiology and secondary chemistry of living plants because ethylene has been shown to enhance production of defensive phytochemicals.

The proteomic profile of hair damage.

PubMed

Sinclair, R; Flagler, M J; Jones, L; Rufaut, N; Davis, M G

2012-06-01

Monilethrix is a congenital hair shaft disorder with associated fragility. Many of the changes seen in monilethrix hair on light microscopy and scanning electron microscopy are also seen in hair weathering and cosmetic damage to hair. We used monilethrix as a model to investigate the relationship between hair protein structure and hair strength and resistance to cosmetic insult. We applied proteomic techniques to identify novel peptide damage markers for chemical oxidative damage to hair. The findings suggest that specific sites in the protein structure of hair are targeted during oxidative damage from bleaching, a unique insight into how chemical damage compromises the structural integrity of the hair shaft at the molecular level. Applying proteomics to the study of congenital and acquired hair shaft disorders can deliver new insights into hair damage and novel strategies to strengthen hair. © 2012 The Authors. BJD © 2012 British Association of Dermatologists.

Computational Methods to Assess the Production Potential of Bio-Based Chemicals.

PubMed

Campodonico, Miguel A; Sukumara, Sumesh; Feist, Adam M; Herrgård, Markus J

2018-01-01

Elevated costs and long implementation times of bio-based processes for producing chemicals represent a bottleneck for moving to a bio-based economy. A prospective analysis able to elucidate economically and technically feasible product targets at early research phases is mandatory. Computational tools can be implemented to explore the biological and technical spectrum of feasibility, while constraining the operational space for desired chemicals. In this chapter, two different computational tools for assessing potential for bio-based production of chemicals from different perspectives are described in detail. The first tool is GEM-Path: an algorithm to compute all structurally possible pathways from one target molecule to the host metabolome. The second tool is a framework for Modeling Sustainable Industrial Chemicals production (MuSIC), which integrates modeling approaches for cellular metabolism, bioreactor design, upstream/downstream processes, and economic impact assessment. Integrating GEM-Path and MuSIC will play a vital role in supporting early phases of research efforts and guide the policy makers with decisions, as we progress toward planning a sustainable chemical industry.

Advancing Models and Data for Characterizing Exposures to Chemicals in Consumer Products

EPA Science Inventory

EPA’s Office of Research and Development (ORD) is leading several efforts to develop data and methods for estimating population chemical exposures related to the use of consumer products. New curated chemical, ingredient, and product use information are being collected fro...

Particulate matter air pollution may offset ozone damage to global crop production

NASA Astrophysics Data System (ADS)

Schiferl, Luke D.; Heald, Colette L.

2018-04-01

Ensuring global food security requires a comprehensive understanding of environmental pressures on food production, including the impacts of air quality. Surface ozone damages plants and decreases crop production; this effect has been extensively studied. In contrast, the presence of particulate matter (PM) in the atmosphere can be beneficial to crops given that enhanced light scattering leads to a more even and efficient distribution of photons which can outweigh total incoming radiation loss. This study quantifies the impacts of ozone and PM on the global production of maize, rice, and wheat in 2010 and 2050. We show that accounting for the growing season of these crops is an important factor in determining their air pollution exposure. We find that the effect of PM can offset much, if not all, of the reduction in yield associated with ozone damage. Assuming maximum sensitivity to PM, the current (2010) global net impact of air quality on crop production varies by crop (+5.6, -3.7, and +4.5 % for maize, wheat, and rice, respectively). Future emissions scenarios indicate that attempts to improve air quality can result in a net negative effect on crop production in areas dominated by the PM effect. However, we caution that the uncertainty in this assessment is large, due to the uncertainty associated with crop response to changes in diffuse radiation; this highlights that a more detailed physiological study of this response for common cultivars is crucial.

The new role of HSE in chemical product development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Purinton, R.J. Jr.; Manning, T.S.; Dowell, S.

1996-11-01

Today, Health, Safety, and Environmental issues take a more prominent role than ever before in chemical product development for the global oilfield service industry. Prior to widespread regulatory guidelines, technical problems were solved and well treatment programs were developed using the chemicals which performed the best and were the least expensive for the application. HSE concerns were sometimes addressed from a remedial standpoint, rather than a preventive one throughout the process. With a clearer understanding of the potential impact of chemicals upon people and the environment, along with the ever-increasing array of government regulations, service companies are taking a newmore » approach to product development. HSE-related risks and costs are being assessed early and continued throughout chemical development, with both product and treatment process features then designed accordingly. One service company reflects this approach with its {open_quotes}cradle-to-grave{close_quotes} Product Development and Stewardship program. Integral to this program are planned HSE assessments at each step of development, including Feasibility, Lab Development, Field Testing, Manufacturing, and Commercial Field Introduction. These assessments provide the data necessary to {open_quotes}engineer-in{close_quotes} solutions to potential HSE-related problems, produce viable Risk Management Plans, and promote a smoother path to commercialization. This avoids arriving at the commercial launch point with a product which poses unacceptably high personal or environmental risks, may be restricted or banned in key markets, or requires lengthy and expensive government registrations. In order to optimize R&E resources and ensure continuous evaluation, decision points (to continue, modify, or abandon) are built into the process. Early HSE screenings must be accurate but also relatively quick and inexpensive to be meaningful and economical.« less

Measurement of endocrine disrupting and asthma-associated chemicals in hair products used by Black women.

PubMed

Helm, Jessica S; Nishioka, Marcia; Brody, Julia Green; Rudel, Ruthann A; Dodson, Robin E

2018-08-01

Personal care products are a source of exposure to endocrine disrupting and asthma-associated chemicals. Because use of hair products differs by race/ethnicity, these products may contribute to exposure and disease disparities. This preliminary study investigates the endocrine disrupting and asthma-associated chemical content of hair products used by U.S. Black women. We used gas chromatography/mass spectrometry (GC/MS) to test 18 hair products in 6 categories used by Black women: hot oil treatment, anti-frizz/polish, leave-in conditioner, root stimulator, hair lotion, and relaxer. We tested for 66 chemicals belonging to 10 chemical classes: ultraviolet (UV) filters, cyclosiloxanes, glycol ethers, fragrances, alkylphenols, ethanolamines, antimicrobials, bisphenol A, phthalates, and parabens. The hair products tested contained 45 endocrine disrupting or asthma-associated chemicals, including every targeted chemical class. We found cyclosiloxanes, parabens, and the fragrance marker diethyl phthalate (DEP) at the highest levels, and DEP most frequently. Root stimulators, hair lotions, and relaxers frequently contained nonylphenols, parabens, and fragrances; anti-frizz products contained cyclosiloxanes. Hair relaxers for children contained five chemicals regulated by California's Proposition 65 or prohibited by EU cosmetics regulation. Targeted chemicals were generally not listed on the product label. Hair products used by Black women and children contained multiple chemicals associated with endocrine disruption and asthma. The prevalence of parabens and DEP is consistent with higher levels of these compounds in biomonitoring samples from Black women compared with White women. These results indicate the need for more information about the contribution of consumer products to exposure disparities. A precautionary approach would reduce the use of endocrine disrupting chemicals in personal care products and improve labeling so women can select products consistent with

DEVELOPMENT OF ENVIRONMENTAL INDICES FOR GREEN CHEMICAL PRODUCTION AND USE

EPA Science Inventory

Chemical production, use and disposal cause adverse impacts on the environment. Consequently, much research has been conducted to develop methods for estimating the risk of chemicals and to screen them based on environmental impact. Risk assessment may be subdivide...

Metabolic engineering of yeast for production of fuels and chemicals.

PubMed

Nielsen, Jens; Larsson, Christer; van Maris, Antonius; Pronk, Jack

2013-06-01

Microbial production of fuels and chemicals from renewable carbohydrate feedstocks offers sustainable and economically attractive alternatives to their petroleum-based production. The yeast Saccharomyces cerevisiae offers many advantages as a platform cell factory for such applications. Already applied on a huge scale for bioethanol production, this yeast is easy to genetically engineer, its physiology, metabolism and genetics have been intensively studied and its robustness enables it to handle harsh industrial conditions. Introduction of novel pathways and optimization of its native cellular processes by metabolic engineering are rapidly expanding its range of cell-factory applications. Here we review recent scientific progress in metabolic engineering of S. cerevisiae for the production of bioethanol, advanced biofuels, and chemicals. Copyright © 2013 Elsevier Ltd. All rights reserved.

DNA damage protection against free radicals of two antioxidant neolignan glucosides from sugarcane molasses.

PubMed

Asikin, Yonathan; Takahashi, Makoto; Mizu, Masami; Takara, Kensaku; Oku, Hirosuke; Wada, Koji

2016-03-15

Sugarcane molasses is a potential by-product of the sugarcane manufacturing industry that is rich in antioxidant materials. The present study aimed to obtain antioxidative compounds from sugarcane molasses and to evaluate their ability to protect DNA from oxidative damage. Two neolignan glucosides were isolated from sugarcane molasses using bioassay and UV spectra monitoring-guided fractionation. The compounds were elucidated as (7R,8S)-dehydrodiconiferyl alcohol-4-O-β-d-glucoside (1) and (7S,8R)-simulanol-9'-O-β-d-glucoside (2). Neolignan glucoside 2 protected against DNA damage caused by free radicals more effectively than did neolignan glucoside 1 (13.62 and 9.08 µmol L(-1) for peroxyl and hydroxyl radicals, respectively, compared to 48.07 and 14.42 µmol L(-1) ). Additionally, neolignan glucoside 2 exhibited superior DNA protection against free radicals compared with various known antioxidative compounds, including p-coumaric acid, ferulic acid, vanillic acid and epigallocatechin gallate. The isolated neolignan glucosides from sugarcane molasses are able to protect DNA from oxidative damage caused by free radicals. This is the first identification of these two compounds in sugarcane molasses. The sugarcane molasses can therefore be used as potential nutraceutical preventative agents, and the findings may foster the utilization of this by-product as a bioresource-based product. © 2015 Society of Chemical Industry. Copyright © 2015 Society of Chemical Industry.

Use of Natural Products as Chemical Library for Drug Discovery and Network Pharmacology

PubMed Central

Gu, Jiangyong; Gui, Yuanshen; Chen, Lirong; Yuan, Gu; Lu, Hui-Zhe; Xu, Xiaojie

2013-01-01

Background Natural products have been an important source of lead compounds for drug discovery. How to find and evaluate bioactive natural products is critical to the achievement of drug/lead discovery from natural products. Methodology We collected 19,7201 natural products structures, reported biological activities and virtual screening results. Principal component analysis was employed to explore the chemical space, and we found that there was a large portion of overlap between natural products and FDA-approved drugs in the chemical space, which indicated that natural products had large quantity of potential lead compounds. We also explored the network properties of natural product-target networks and found that polypharmacology was greatly enriched to those compounds with large degree and high betweenness centrality. In order to make up for a lack of experimental data, high throughput virtual screening was employed. All natural products were docked to 332 target proteins of FDA-approved drugs. The most potential natural products for drug discovery and their indications were predicted based on a docking score-weighted prediction model. Conclusions Analysis of molecular descriptors, distribution in chemical space and biological activities of natural products was conducted in this article. Natural products have vast chemical diversity, good drug-like properties and can interact with multiple cellular target proteins. PMID:23638153

Alkaline ceramidase 2 and its bioactive product sphingosine are novel regulators of the DNA damage response

PubMed Central

Xu, Ruijuan; Wang, Kai; Mileva, Izolda; Hannun, Yusuf A.; Obeid, Lina M.; Mao, Cungui

2016-01-01

Human cells respond to DNA damage by elevating sphingosine, a bioactive sphingolipid that induces programmed cell death (PCD) in response to various forms of stress, but its regulation and role in the DNA damage response remain obscure. Herein we demonstrate that DNA damage increases sphingosine levels in tumor cells by upregulating alkaline ceramidase 2 (ACER2) and that the upregulation of the ACER2/sphingosine pathway induces PCD in response to DNA damage by increasing the production of reactive oxygen species (ROS). Treatment with the DNA damaging agent doxorubicin increased both ACER2 expression and sphingosine levels in HCT116 cells in a dose-dependent manner. ACER2 overexpression increased sphingosine in HeLa cells whereas knocking down ACER2 inhibited the doxorubicin-induced increase in sphingosine in HCT116 cells, suggesting that DNA damage elevates sphingosine by upregulating ACER2. Knocking down ACER2 inhibited an increase in the apoptotic and necrotic cell population and the cleavage of poly ADP ribose polymerase (PARP) in HCT116 cells in response to doxorubicin as well as doxorubicin-induced release of lactate dehydrogenase (LDH) from these cells. Similar to treatment with doxorubicin, ACER2 overexpression induced an increase in the apoptotic and necrotic cell population and PARP cleavage in HeLa cells and LDH release from cells, suggesting that ACER2 upregulation mediates PCD in response to DNA damage through sphingosine. Mechanistic studies demonstrated that the upregulation of the ACER2/sphingosine pathway induces PCD by increasing ROS levels. Taken together, these results suggest that the ACER2/sphingosine pathway mediates PCD in response to DNA damage through ROS production. PMID:26943039

Biorefineries for the production of top building block chemicals and their derivatives.

PubMed

Choi, Sol; Song, Chan Woo; Shin, Jae Ho; Lee, Sang Yup

2015-03-01

Due to the growing concerns on the climate change and sustainability on petrochemical resources, DOE selected and announced the bio-based top 12 building blocks and discussed the needs for developing biorefinery technologies to replace the current petroleum based industry in 2004. Over the last 10 years after its announcement, many studies have been performed for the development of efficient technologies for the bio-based production of these chemicals and derivatives. Now, ten chemicals among these top 12 chemicals, excluding the l-aspartic acid and 3-hydroxybutyrolactone, have already been commercialized or are close to commercialization. In this paper, we review the current status of biorefinery development for the production of these platform chemicals and their derivatives. In addition, current technological advances on industrial strain development for the production of platform chemicals using micro-organisms will be covered in detail with case studies on succinic acid and 3-hydroxypropionic acid as examples. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Most plastic products release estrogenic chemicals: a potential health problem that can be solved.

PubMed

Yang, Chun Z; Yaniger, Stuart I; Jordan, V Craig; Klein, Daniel J; Bittner, George D

2011-07-01

Chemicals having estrogenic activity (EA) reportedly cause many adverse health effects, especially at low (picomolar to nanomolar) doses in fetal and juvenile mammals. We sought to determine whether commercially available plastic resins and products, including baby bottles and other products advertised as bisphenol A (BPA) free, release chemicals having EA. We used a roboticized MCF-7 cell proliferation assay, which is very sensitive, accurate, and repeatable, to quantify the EA of chemicals leached into saline or ethanol extracts of many types of commercially available plastic materials, some exposed to common-use stresses (microwaving, ultraviolet radiation, and/or autoclaving). Almost all commercially available plastic products we sampled--independent of the type of resin, product, or retail source--leached chemicals having reliably detectable EA, including those advertised as BPA free. In some cases, BPA-free products released chemicals having more EA than did BPA-containing products. Many plastic products are mischaracterized as being EA free if extracted with only one solvent and not exposed to common-use stresses. However, we can identify existing compounds, or have developed, monomers, additives, or processing agents that have no detectable EA and have similar costs. Hence, our data suggest that EA-free plastic products exposed to common-use stresses and extracted by saline and ethanol solvents could be cost-effectively made on a commercial scale and thereby eliminate a potential health risk posed by most currently available plastic products that leach chemicals having EA into food products.

Identifying new persistent and bioaccumulative organics among chemicals in commerce. III: byproducts, impurities, and transformation products.

PubMed

Howard, Philip H; Muir, Derek C G

2013-05-21

The goal of this series of studies was to identify commercial chemicals that might be persistent and bioaccumulative (PB) and that were not being considered in current wastewater and aquatic environmental measurement programs. In this study, we focus on chemicals that are not on commercial chemical lists such as U.S. EPA's Inventory Update Rule but may be found as byproducts or impurities in commercial chemicals or are likely transformation products from commercial chemical use. We evaluated the 610 chemicals from our earlier publication as well as high production volume chemicals and identified 320 chemicals (39 byproducts and impurities, and 281 transformation products) that could be potential PB chemicals. Four examples are discussed in detail; these chemicals had a fair amount of information on the commercial synthesis and byproducts and impurities that might be found in the commercial product. Unfortunately for many of the 610 chemicals, as well as the transformation products, little or no information was available. Use of computer-aided software to predict the transformation pathways in combination with the biodegradation rules of thumb and some basic organic chemistry has allowed 281 potential PB transformation products to be suggested for some of the 610 commercial chemicals; more PB transformation products were not selected since microbial degradation often results in less persistent and less bioaccumulative metabolites.

Damage to Aspergillus fumigatus and Rhizopus oryzae Hyphae by Oxidative and Nonoxidative Microbicidal Products of Human Neutrophils In Vitro

PubMed Central

Diamond, Richard D.; Clark, Robert A.

1982-01-01

Our previous studies established that human neutrophils could damage and probably kill hyphae of Aspergillus fumigatus and Rhizopus oryzae in vitro, primarily by oxygen-dependent mechanisms active at the cell surface. These studies were extended, again quantitating hyphal damage by reduction in uptake of 14C-labeled uracil or glutamine. Neither A. fumigatus nor R. oryzae hyphae were damaged by neutrophils from patients with chronic granulomatous disease, confirming the importance of oxidative mechanisms in damage to hyphae. In contrast, neutrophils from one patient with hereditary myeloperoxidase deficiency damaged R. oryzae but not A. fumigatus hyphae. Cell-free, in vitro systems were then used to help determine the relative importance of several potentially fungicidal products of neutrophils. Both A. fumigatus and R. oryzae hyphae were damaged by the myeloperoxidase-hydrogen peroxide-halide system either with reagent hydrogen peroxide or enzymatic systems for generating hydrogen peroxide (glucose oxidase with glucose, or xanthine oxidase with either hypoxanthine or acetaldehyde). Iodide with or without chloride supported the reaction, but damage was less with chloride alone as the halide cofactor. Hydrogen peroxide alone damaged hyphae only in concentrations ≥1 mM, but 0.01 mM hypochlorous acid, a potential product of the myeloperoxidase system, significantly damaged R. oryzae hyphae (a 1 mM concentration was required for significant damage to A. fumigatus hyphae). Damage to hyphae by the myeloperoxidase system was inhibited by azide, cyanide, catalase, histidine, and tryptophan, but not by superoxide dismutase, dimethyl sulfoxide, or mannitol. Photoactivation of the dye rose bengal resulted in hyphal damage which was inhibited by histidine, tryptophan, and 1,4-diazobicyclo(2,2,2)octane. Lysates of neutrophils or separated neutrophil granules did not affect A. fumigatus hyphae, but did damage R. oryzae hyphae. Similarly, three preparations of cationic proteins

Chemical and toxicological characteristics of conventional and low-TSNA moist snuff tobacco products.

PubMed

Song, Min-Ae; Marian, Catalin; Brasky, Theodore M; Reisinger, Sarah; Djordjevic, Mirjana; Shields, Peter G

2016-03-14

Use of smokeless tobacco products (STPs) is associated with oral cavity cancer and other health risks. Comprehensive analysis for chemical composition and toxicity is needed to compare conventional and newer STPs with lower tobacco-specific nitrosamines (TSNAs) yields. Seven conventional and 12 low-TSNA moist snuff products purchased in the U.S., Sweden, and South Africa were analyzed for 18 chemical constituents (International Agency for Research on Cancer classified carcinogens), pH, nicotine, and free nicotine. Chemicals were compared in each product using Wilcoxon rank-sum test and principle component analysis (PCA). Conventional compared to low-TSNA moist snuff products had higher ammonia, benzo[a]pyrene, cadmium, nickel, nicotine, nitrate, and TSNAs and had lower arsenic in dry weight content and per mg nicotine. Lead and chromium were significantly higher in low-TSNA moist snuff products. PCA showed a clear difference for constituents between conventional and low-TSNA moist snuff products. Differences among products were reduced when considered on a per mg nicotine basis. As one way to contextualize differences in constituent levels, probabilistic lifetime cancer risk was estimated for chemicals included in The University of California's carcinogenic potency database (CPDB). Estimated probabilistic cancer risks were 3.77-fold or 3-fold higher in conventional compared to low-TSNA moist snuff products under dry weight or under per mg nicotine content, respectively. In vitro testing for the STPs indicated low level toxicity and no substantial differences. The comprehensive chemical characterization of both conventional and low-TSNA moist snuff products from this study provides a broader assessment of understanding differences in carcinogenic potential of the products. In addition, the high levels and probabilistic cancer risk estimates for certain chemical constituents of smokeless tobacco products will further inform regulatory decision makers and aid them in

15 CFR 714.3 - Advance declaration requirements for additionally planned production of Schedule 3 chemicals.

Code of Federal Regulations, 2011 CFR

2011-01-01

... COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 3 CHEMICALS § 714.3 Advance declaration requirements for additionally planned production of Schedule 3 chemicals. (a) Declaration... additionally planned production of Schedule 3 chemicals. 714.3 Section 714.3 Commerce and Foreign Trade...

Radiation damage of gallium arsenide production cells

NASA Technical Reports Server (NTRS)

Mardesich, N.; Garlick, G. F. J.

1987-01-01

High-efficiency gallium arsenide cells, made by the liquid epitaxy method (LPE), have been irradiated with 1-MeV electrons up to fluences of 10 to the 16th e/sq cm. Measurements have been made of cell spectral response and dark and light-excited current-voltage characteristics and analyzed using computer-based models to determine underlying parameters such as damage coefficients. It is possible to use spectral response to sort out damage effects in the different cell component layers. Damage coefficients are similar to other reported in the literature for the emitter and buffer (base). However, there is also a damage effect in the window layer and possibly at the window emitter interface similar to that found for proton-irradiated liquid-phase epitaxy-grown cells. Depletion layer recombination is found to be less than theoretically expected at high fluence.

Permeability recovery of damaged water sensitive core using ultrasonic waves.

PubMed

Khan, Nasir; Pu, Chunsheng; Li, Xu; He, Yanlong; Zhang, Lei; Jing, Cheng

2017-09-01

It is imperative to recover the well productivity lose due to formation damage nearby wellbore during variant well operations. Some indispensable issues in conventional techniques make ultrasonic technology more attractive due to simple, reliable, favorable, cost-effective, and environment friendly nature. This study proposes the independent and combined use of ultrasonic waves and chemical agents for the treatment of already damaged core samples caused by exposure to distilled water. Results elucidate that ultrasonic waves with optimum (20kHz, 1000W) instead of maximum frequency and power worked well in the recovery owing to peristaltic transport caused by matching of natural frequency with acoustic waves frequency. In addition, hundred minutes was investigated as optimum irradiation time which provided ample time span to detach fine loosely suspended particles. However, further irradiation adversely affected the damaged permeability recovery. Moreover, permeability improvement attributes to cavitation due to ultrasonic waves propagation through fluid contained in porous medium and thermal energy generated by three different ways. Eventually, experimental outcomes indicated that maximum (25.3%) damaged permeability recovery was witnessed by applying ultrasonic waves with transducer #2 (20kHz and 1000W) and optimum irradiation timeframe (100min). This recovery was further increased to 45.8% by applying chemical agent and optimum ultrasonic waves simultaneously. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of dieldrin in the glue line of oak plywood panels in preventing Lyctus beetle damage

Treesearch

Thomas McIntyre

1961-01-01

For many years the lumber industry has been seeking improved methods of preventing decay and insect damage to lumber and other wood products. One relatively new approach to this problem is the addition of toxic chemicals in plywood glues to prevent infestations or restrict feeding injury by wood-boring insects. Wood products treated in this manner have been marketed in...

Most Plastic Products Release Estrogenic Chemicals: A Potential Health Problem That Can Be Solved

PubMed Central

Yang, Chun Z.; Yaniger, Stuart I.; Jordan, V. Craig; Klein, Daniel J.

2011-01-01

Background: Chemicals having estrogenic activity (EA) reportedly cause many adverse health effects, especially at low (picomolar to nanomolar) doses in fetal and juvenile mammals. Objectives: We sought to determine whether commercially available plastic resins and products, including baby bottles and other products advertised as bisphenol A (BPA) free, release chemicals having EA. Methods: We used a roboticized MCF-7 cell proliferation assay, which is very sensitive, accurate, and repeatable, to quantify the EA of chemicals leached into saline or ethanol extracts of many types of commercially available plastic materials, some exposed to common-use stresses (microwaving, ultraviolet radiation, and/or autoclaving). Results: Almost all commercially available plastic products we sampled—independent of the type of resin, product, or retail source—leached chemicals having reliably detectable EA, including those advertised as BPA free. In some cases, BPA-free products released chemicals having more EA than did BPA-containing products. Conclusions: Many plastic products are mischaracterized as being EA free if extracted with only one solvent and not exposed to common-use stresses. However, we can identify existing compounds, or have developed, monomers, additives, or processing agents that have no detectable EA and have similar costs. Hence, our data suggest that EA-free plastic products exposed to common-use stresses and extracted by saline and ethanol solvents could be cost-effectively made on a commercial scale and thereby eliminate a potential health risk posed by most currently available plastic products that leach chemicals having EA into food products. PMID:21367689

Ecological Risk Assessment of Chemicals Migrated from a Recycled Plastic Product

PubMed Central

Roh, Ji-Yeon; Kim, Min-Hyuck; Kim, Woo Il; Kang, Young-Yeul; Shin, Sun Kyoung; Kim, Jong-Guk

2013-01-01

Objectives Potential environmental risks caused by chemicals that could be released from a recycled plastic product were assessed using a screening risk assessment procedure for chemicals in recycled products. Methods Plastic slope protection blocks manufactured from recycled plastics were chosen as model recycled products. Ecological risks caused by four model chemicals -di-(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP), cadmium (Cd), and lead (Pb)- were assessed. Two exposure models were built for soil below the block and a hypothetic stream receiving runoff water. Based on the predicted no-effect concentrations for the selected chemicals and exposure scenarios, the allowable leaching rates from and the allowable contents in the recycled plastic blocks were also derived. Results Environmental risks posed by slope protection blocks were much higher in the soil compartment than in the hypothetic stream. The allowable concentrations in leachate were 1.0×10-4, 1.2×10-5, 9.5×10-3, and 5.3×10-3 mg/L for DEHP, DINP, Cd, and Pb, respectively. The allowable contents in the recycled products were 5.2×10-3, 6.0×10-4, 5.0×10-1, and 2.7×10-1 mg/kg for DEHP, DINP, Cd, and Pb, respectively. Conclusions A systematic ecological risk assessment approach for slope protection blocks would be useful for regulatory decisions for setting the allowable emission rates of chemical contaminants, although the method needs refinement. PMID:24303349

Coupling chemical weathering with soil production across soil-mantled landscapes

USGS Publications Warehouse

Burke, B.C.; Heimsath, A.M.; White, A.F.

2007-01-01

Soil-covered upland landscapes constitute a critical part of the habitable world. Our understanding of how they evolve as a function of different climatic, tectonic and geological regimes is important across a wide range of disciplines and depends, in part, on understanding the links between chemical and physical weathering processes. Extensive previous work has shown that soil production rates decrease with increasing soil column thickness, but chemical weathering rates were not measured. Here we examine a granitic, soil-mantled hillslope at Point Reyes, California, where soil production rates were determined using in situ produced cosmogenic nuclides (10Be and 26Al), and we quantify the extent as well as the rates of chemical weathering of the saprolite from beneath soil from across the landscape. We collected saprolite samples from the base of soil pits and analysed them for abrasion pH as well as for major and trace elements by X-ray fluorescence spectroscopy, and for clay mineralogy by X-ray diffraction spectroscopy. Our results show for the first time that chemical weathering rates decrease with increasing soil thickness and account for 13 to 51 per cent of total denudation. We also show that spatial variation in chemical weathering appears to be topographically controlled: weathering rate decreases with slope across the divergent ridge and increases with upslope contributing area in the convergent swale. Furthermore, to determine the best measure for the extent of saprolite weathering, we compared four different chemical weathering indices - the Vogt ratio, the chemical index of alteration (CIA), Parker's index, and the silicon-aluminium ratio - with saprolite pH. Measurements of the CIA were the most closely correlated with saprolite pH, showing that weathering intensity decreases linearly with an increase in saprolite pH from 4.7 to almost 7. Data presented here are among the first to couple directly rates of soil production and chemical weathering with

Thermal effects in Cs DPAL and alkali cell window damage

NASA Astrophysics Data System (ADS)

Zhdanov, B. V.; Rotondaro, M. D.; Shaffer, M. K.; Knize, R. J.

2016-10-01

Experiments on power scaling of Diode Pumped Alkali Lasers (DPALs) revealed some limiting parasitic effects such as alkali cell windows and gain medium contamination and damage, output power degradation in time and others causing lasing efficiency decrease or even stop lasing1 . These problems can be connected with thermal effects, ionization, chemical interactions between the gain medium components and alkali cells materials. Study of all these and, possibly, other limiting effects and ways to mitigate them is very important for high power DPAL development. In this talk we present results of our experiments on temperature measurements in the gain medium of operating Cs DPAL at different pump power levels in the range from lasing threshold to the levels causing damage of the alkali cell windows. For precise contactless in situ temperature measurements, we used an interferometric technique, developed in our lab2 . In these experiments we demonstrated that damage of the lasing alkali cell starts in the bulk with thermal breakdown of the hydrocarbon buffer gas. The degradation processes start at definite critical temperatures of the gain medium, different for each mixture of buffer gas. At this critical temperature, the hydrocarbon and the excited alkali metal begin to react producing the characteristic black soot and, possibly, some other chemical compounds, which both harm the laser performance and significantly increase the harmful heat deposition within the laser medium. This soot, being highly absorptive, is catastrophically heated to very high temperatures that visually observed as bulk burning. This process quickly spreads to the cell windows and causes their damage. As a result, the whole cell is also contaminated with products of chemical reactions.

Interested consumers' awareness of harmful chemicals in everyday products.

PubMed

Hartmann, Sabrina; Klaschka, Ursula

2017-01-01

Everyday products can contain a multitude of harmful substances unnoticed by most consumers, because established risk communication channels reach only part of the society. The question is, whether at least interested and informed consumers are able to use risk communication tools and assess harmful chemicals in products. An online survey investigated the awareness of 1030 consumers on harmful substances in everyday items. Participating consumers' education level, knowledge in chemistry, and motivation were above society's average. Although a large number of responses showed that survey participants were familiar with several aspects of the issue, the results revealed that knowledge in chemistry helped, but was not enough. Many participants assumed that products with an eco-label, natural personal care products, products without hazard pictograms or products produced in the European Union would not contain harmful substances. Most participants indicated to use hazard pictograms, information on the packaging, reports in the media, and environmental and consumer organizations as information sources, while information by authorities and manufacturers were not named frequently and did not receive high confidence. Smartphone applications were not indicated by many participants as information sources. The information sources most trusted were environmental and consumer organizations, hazard pictograms, and lists of ingredients on the containers. The declared confidence in certain risk communication instruments did not always correspond to the use frequencies indicated. Nearly all participants considered legislators as responsible for the reduction of harmful substances in consumer products. Misconceptions about harmful substances in products can be dangerous for the personal health and the environment. The survey indicates that motivation, educational level, and chemical expertise do not automatically provide an appropriate understanding of harmful substances in products

Artificial photosynthesis for sustainable fuel and chemical production.

PubMed

Kim, Dohyung; Sakimoto, Kelsey K; Hong, Dachao; Yang, Peidong

2015-03-09

The apparent incongruity between the increasing consumption of fuels and chemicals and the finite amount of resources has led us to seek means to maintain the sustainability of our society. Artificial photosynthesis, which utilizes sunlight to create high-value chemicals from abundant resources, is considered as the most promising and viable method. This Minireview describes the progress and challenges in the field of artificial photosynthesis in terms of its key components: developments in photoelectrochemical water splitting and recent progress in electrochemical CO2 reduction. Advances in catalysis, concerning the use of renewable hydrogen as a feedstock for major chemical production, are outlined to shed light on the ultimate role of artificial photosynthesis in achieving sustainable chemistry. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chemical and Common Burns in Children.

PubMed

Yin, Shan

2017-05-01

Burns are a common cause of preventable morbidity and mortality in children. Thermal and chemical burns are the most common types of burns. Their clinical appearance can be similar and the treatment is largely similar. Thermal burns in children occur primarily after exposure to a hot surface or liquid, or contact with fire. Burns are typically classified based on the depth and total body surface area, and the severity and onset of the burn can also depend on the temperature and duration of contact. Chemical burns are caused by chemicals-most commonly acids and alkalis-that can damage the skin on contact. In children, the most common cause of chemical burns is from household products such as toilet bowl cleaners, drain cleaners, detergents, and bleaches. Mild chemical burns generally cause redness and pain and can look similar to other common rashes or skin infections, whereas severe chemical burns are more extreme and may cause redness, blistering, skin peeling, and swelling.

Intraspecific chemical diversity among neighbouring plants correlates positively with plant size and herbivore load but negatively with herbivore damage.

PubMed

Bustos-Segura, Carlos; Poelman, Erik H; Reichelt, Michael; Gershenzon, Jonathan; Gols, Rieta

2017-01-01

Intraspecific plant diversity can modify the properties of associated arthropod communities and plant fitness. However, it is not well understood which plant traits determine these ecological effects. We explored the effect of intraspecific chemical diversity among neighbouring plants on the associated invertebrate community and plant traits. In a common garden experiment, intraspecific diversity among neighbouring plants was manipulated using three plant populations of wild cabbage that differ in foliar glucosinolates. Plants were larger, harboured more herbivores, but were less damaged when plant diversity was increased. Glucosinolate concentration differentially correlated with generalist and specialist herbivore abundance. Glucosinolate composition correlated with plant damage, while in polycultures, variation in glucosinolate concentrations among neighbouring plants correlated positively with herbivore diversity and negatively with plant damage levels. The results suggest that intraspecific variation in secondary chemistry among neighbouring plants is important in determining the structure of the associated insect community and positively affects plant performance. © 2016 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

Regulation of chemicals in children's products: How U.S. and EU regulation impacts small markets.

PubMed

Negev, Maya; Berman, Tamar; Reicher, Shay; Balan, Simona; Soehl, Anna; Goulden, Shula; Ardi, Ruti; Shammai, Yaniv; Hadar, Laura; Blum, Arlene; Diamond, Miriam L

2018-03-01

Toys and children's products may contain trace metals and organic compounds that are potentially harmful to the health and development of infants and young children. Intergovernmental organizations and individual countries regulate chemicals in consumer products, but a coordinated international approach is lacking. This paper examines the implications of chemical regulation in children's products in large markets for a smaller market, namely Israel. We compared chemical regulations in children's products in the U.S., EU and Israel, and conducted in-depth interviews with diverse stakeholders in the Israeli product standardization process. Israel adopted EU chemical standards for certain chemicals (e.g., trace metals, phthalates) but not others (e.g., bisphenol A, flame retardants, trace metals in children's jewelry). Israeli regulation of chemicals in consumer products relies on regulations in large markets such as the U.S. and EU, which therefore have impacts beyond their territories. However, Israel adopts only product-specific standards and has regulatory gaps due to the lack of an overarching regulatory approach that exists in the U.S. and the EU. Furthermore, Israeli policy is to adopt parallel standards from large markets in order to remove trade barriers, despite their different approaches to chemical regulation, an approach which prioritizes trade considerations over health considerations. We conclude with policy recommendations for Israel, which have relevance for other small markets. Copyright © 2017 Elsevier B.V. All rights reserved.

High-throughput exposure modeling to support prioritization of chemicals in personal care products

EPA Science Inventory

We demonstrate the application of a high-throughput modeling framework to estimate exposure to chemicals used in personal care products (PCPs). As a basis for estimating exposure, we use the product intake fraction (PiF), defined as the mass of chemical taken by an individual or ...

Harvest operations for density management: planning requirements, production, costs, stand damage, and recommendations

Treesearch

Loren D. Kellogg; Stephen J. Pilkerton

2013-01-01

Since the early 1990s, several studies have been undertaken to determine the planning requirements, productivity, costs, and residual stand damage of harvest operations in thinning treatments designed to promote development of complex forest structure in order to enhance ecological functioning and biological diversity. Th ese studies include the Oregon State...

Nomenclature associated with chemical characterization of and compatibility evaluations for medical product delivery systems.

PubMed

Jenke, Dennis R

2003-01-01

Delivery systems are used to store, contain, and/or administer liquid pharmaceutical products. Gaining an understanding of the chemical composition of such a delivery system is necessary with respect to effective system development, registration, and production. Additionally, the ability of the delivery system to impact the chemical composition of the contacted product may define the safety and/or efficacy of the product. Assessing the compatibility of the delivery system and the product is thus both necessary and desirable. The nomenclature associated with compatibility assessments has not been standardized, oftimes leading to conflicting or confusing information. This manuscript puts forth a nomenclature which classifies those chemical entities which participate in the system/product interaction and delineates the various extraction strategies which may be used in compatibility assessments.

New methods to monitor emerging chemicals in the drinking water production chain.

PubMed

van Wezel, Annemarie; Mons, Margreet; van Delft, Wouter

2010-01-01

New techniques enable a shift in monitoring chemicals that affect water quality from mainly at the end product, tap water, towards monitoring during the whole process along the production chain. This is congruent with the 'HACCP' system (hazard analysis of critical control points) that is fairly well integrated into food production but less well in drinking water production. This shift brings about more information about source quality, the efficiency of treatment and distribution, and understanding of processes within the production chain, and therefore can lead to a more pro-active management of drinking water production. At present, monitoring is focused neither on emerging chemicals, nor on detection of compounds with chronic toxicity. We discuss techniques to be used, detection limits compared to quality criteria, data interpretation and possible interventions in production.

9 CFR 318.16 - Pesticide chemicals and other residues in products.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., DEPARTMENT OF AGRICULTURE AGENCY ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION... ingredients. Residues of pesticide chemicals, food additives and color additives or other substances in or on ingredients (other than meat, meat byproducts, and meat food products) used in the formulation of products...

Anaerobic Fermentation for Production of Carboxylic Acids as Bulk Chemicals from Renewable Biomass.

PubMed

Wang, Jufang; Lin, Meng; Xu, Mengmeng; Yang, Shang-Tian

Biomass represents an abundant carbon-neutral renewable resource which can be converted to bulk chemicals to replace petrochemicals. Carboxylic acids have wide applications in the chemical, food, and pharmaceutical industries. This chapter provides an overview of recent advances and challenges in the industrial production of various types of carboxylic acids, including short-chain fatty acids (acetic, propionic, butyric), hydroxy acids (lactic, 3-hydroxypropionic), dicarboxylic acids (succinic, malic, fumaric, itaconic, adipic, muconic, glucaric), and others (acrylic, citric, gluconic, pyruvic) by anaerobic fermentation. For economic production of these carboxylic acids as bulk chemicals, the fermentation process must have a sufficiently high product titer, productivity and yield, and low impurity acid byproducts to compete with their petrochemical counterparts. System metabolic engineering offers the tools needed to develop novel strains that can meet these process requirements for converting biomass feedstock to the desirable product.

76 FR 78610 - Notice of Intent To Suspend the Nursery Production, the Nursery and Floriculture Chemical Use...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-19

... Nursery Production, the Nursery and Floriculture Chemical Use, and the Christmas Tree Production Surveys... and Christmas Tree Production Surveys along with the Nursery and Floriculture Chemical Use Survey... of All Nursery and Christmas Tree Production Surveys Along with the Nursery and Floriculture Chemical...

Micromachined chemical jet dispenser

DOEpatents

Swierkowski, Steve P.

1999-03-02

A dispenser for chemical fluid samples that need to be precisely ejected in size, location, and time. The dispenser is a micro-electro-mechanical systems (MEMS) device fabricated in a bonded silicon wafer and a substrate, such as glass or silicon, using integrated circuit-like fabrication technology which is amenable to mass production. The dispensing is actuated by ultrasonic transducers that efficiently produce a pressure wave in capillaries that contain the chemicals. The 10-200 .mu.m diameter capillaries can be arranged to focus in one spot or may be arranged in a larger dense linear array (.about.200 capillaries). The dispenser is analogous to some ink jet print heads for computer printers but the fluid is not heated, thus not damaging certain samples. Major applications are in biological sample handling and in analytical chemical procedures such as environmental sample analysis, medical lab analysis, or molecular biology chemistry experiments.

[Cytotoxicity of chemicals used in household products: estimation of eye irritating potency of 25 chemicals tested during 1991-1996].

PubMed

Ikarashi, Y; Tsuchiya, T; Nakamura, A

1997-01-01

Cytotoxicity potential of chemicals was evaluated by determining the concentrations inducing 50% reduction of neutral red (NR) uptake into Chinese hamster fibroblast V79 cells compared with control culture (IC50). The results of cytotoxicity test for surfactants with the data produced by the in vivo Draize eye and skin irritation test were compared. There was a good correlation between cytotoxicity and eye irritation score obtained from the Draize test. In contrast, no correlation was observed between Draize skin irritation score and cytotoxic potential of chemicals. Therefore, the NR cytotoxicity test was regarded as a possible in vitro model for predicting eye irritation. Based on the IC50 values in the NR cytotoxicity test, the eye irritation classification (weak, moderate and strong) for each chemical used in household products has been established. We evaluated the cytotoxicity of 25 chemicals used for antimicrobial, rubber accelerator, rubber antioxidant, ultraviolet absorber etc. in household products, and estimated the eye irritating potency of these test chemicals according to the criterion.

Exploring consumer exposure pathways and patterns of use for chemicals in the environment through the Chemical/Product Categories Database

EPA Pesticide Factsheets

Exploring consumer exposure pathways and patterns of use for chemicals in the environment through the Chemical/Product Categories Database (CPCat) (Presented by: Kathie Dionisio, Sc.D., NERL, US EPA, Research Triangle Park, NC (1/23/2014).

Fragranced consumer products: Chemicals emitted, ingredients unlisted

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steinemann, Anne C., E-mail: acstein@u.washington.ed; MacGregor, Ian C.; Gordon, Sydney M.

2011-04-15

Fragranced consumer products are pervasive in society. Relatively little is known about the composition of these products, due to lack of prior study, complexity of formulations, and limitations and protections on ingredient disclosure in the U.S. We investigated volatile organic compounds (VOCs) emitted from 25 common fragranced consumer products-laundry products, personal care products, cleaning supplies, and air fresheners-using headspace analysis with gas chromatography/mass spectrometry (GC/MS). Our analysis found 133 different VOCs emitted from the 25 products, with an average of 17 VOCs per product. Of these 133 VOCs, 24 are classified as toxic or hazardous under U.S. federal laws, andmore » each product emitted at least one of these compounds. For 'green' products, emissions of these compounds were not significantly different from the other products. Of all VOCs identified across the products, only 1 was listed on any product label, and only 2 were listed on any material safety data sheet (MSDS). While virtually none of the chemicals identified were listed, this nonetheless accords with U.S. regulations, which do not require disclosure of all ingredients in a consumer product, or of any ingredients in a mixture called 'fragrance.' Because the analysis focused on compounds emitted and listed, rather than exposures and effects, it makes no claims regarding possible risks from product use. Results of this study contribute to understanding emissions from common products, and their links with labeling and legislation.« less

Engineering an Obligate Photoautotrophic Cyanobacterium to Utilize Glycerol for Growth and Chemical Production.

PubMed

Kanno, Masahiro; Atsumi, Shota

2017-01-20

Cyanobacteria have attracted much attention as a means to directly recycle carbon dioxide into valuable chemicals that are currently produced from petroleum. However, the titers and productivities achieved are still far below the level required in industry. To make a more industrially applicable production scheme, glycerol, a byproduct of biodiesel production, can be used as an additional carbon source for photomixotrophic chemical production. Glycerol is an ideal candidate due to its availability and low cost. In this study, we found that a heterologous glycerol respiratory pathway enabled Synechococcus elongatus PCC 7942 to utilize extracellular glycerol. The engineered strain produced 761 mg/L of 2,3-butanediol in 48 h with a 290% increase over the control strain under continuous light conditions. Glycerol supplementation also allowed for continuous cell growth and 2,3-butanediol production in diurnal light conditions. These results highlight the potential of glycerol as an additional carbon source for photomixotrophic chemical production in cyanobacteria.

Characterization of Stachybotrys from water-damaged buildings based on morphology, growth, and metabolite production.

PubMed

Andersen, Birgitte; Nielsen, Kristian F; Jarvis, Bruce B

2002-01-01

Stachybotrys was found to be associated with idiopathic pulmonary hemorrhage in infants in Cleveland, Ohio. Since that time, considerable effort has been put into finding the toxic components responsible for the disease. The name Stachybotrys chartarum has been applied to most of these isolates, but inconsistent toxicity results and taxonomic confusion prompted the present study. In this study, 122 Stachybotrys isolates, mainly from water-damaged buildings, were characterized and identified by combining three different approaches: morphology, colony characteristics, and metabolite production. Two different Stachybotrys taxa, S. chartarum and one undescribed species, were found in water-damaged buildings regardless of whether the buildings were in Denmark, Finland, or the USA. Furthermore, two chemotypes could be distinguished in S. chartarum. One chemotype produced atranones, whereas the other was a macrocyclic trichothecene-producer. The second undescribed taxon produced atranones and could be differentiated from S. chartarum by its growth characteristics and pigment production. Our results correlate with different inflammatory and toxicological properties reported for these same isolates and show that the three taxa/chemotypes should be treated separately. The co-occurrence of these three taxa/chemotypes in water-damaged buildings explains the inconsistent results in the literature concerning toxicity of Stachybotrys isolated from that environment.

Prostacyclin production in rabbit arteries in situ: inhibition by arachidonic acid-induced endothelial cell damage or by low-dose aspirin.

PubMed

Ingerman-Wojenski, C; Silver, M J; Smith, J B; Nissenbaum, M; Sedar, A W

1981-04-01

The central artery of the rabbit ear was perfused in situ and effluent fractions from the artery were assayed for 6-keto-prostaglandin F1 alpha (6-K-PGF1 alpha) and thromboxane B2 (TxB2), the stable metabolites of prostacyclin (PGI2) and TxA2, using specific radioimmunoassays. These metabolites of arachidonic acid (AA) were not detected in the effluent during infusion of Tyrode's solution but both metabolites were detected when small amounts of AA were infused into the artery. Examination of the arteries by scanning electron microscopy revealed that high concentrations of AA which caused a short burst of 6-K-PGF1 alpha and TxB2 production damaged the endothelial cells while lower concentrations which stimulated continuous production did not cause damage. When a non-damaging concentration of AA was infused into an artery that had previously received a damaging concentration, PG production was greatly reduced. Pretreatment of the rabbits with 4 mg/kg acetyl-salicylic acid (ASA) inhibited 6-K-PGF1 alpha production by the rabbit ear artery in response to AA and 70% inhibition was still evident 18 hours after ASA.

Production of Korean Idiomatic Utterances Following Left- and Right-Hemisphere Damage: Acoustic Studies

ERIC Educational Resources Information Center

Yang, Seung-yun; Van Lancker Sidtis, Diana

2016-01-01

Purpose: This study investigates the effects of left- and right-hemisphere damage (LHD and RHD) on the production of idiomatic or literal expressions utilizing acoustic analyses. Method: Twenty-one native speakers of Korean with LHD or RHD and in a healthy control (HC) group produced 6 ditropically ambiguous (idiomatic or literal) sentences in 2…

[Developmental neurotoxicity of industrial chemicals].

PubMed

Labie, Dominique

2007-10-01

"A Silent Pandemic : Industrial Chemicals Are Impairing the Brain Development of Children Worldwide" Fetal and early childhood exposures to industrial chemicals in the environment can damage the developing brain and can lead to neurodevelopmental disorders (NDDs)--autism, attention deficit disorder (ADHD), and mental retardation. In a new review study, published in The Lancet, Philip Grandjean and Philip Landrigan from the Harvard School of Public Health systematically examined publicly available data on chemical toxicity in order to identify the industrial chemicals that are the most likely to damage the developing brain. The researchers found that 202 industrial chemicals have the capacity to damage the human brain, and they conclude that chemical pollution may have harmed the brains of millions of children worldwide. The authors conclude further that the toxic effects of industrial chemicals on children have generally been overlooked. In North Amercia, the commission for environmental cooperation, and in European Union the DEVNERTOX projects had reached to the same conclusions. We analyse this review and discuss these rather pessimistic conclusions.

A review of models for near-field exposure pathways of chemicals in consumer products.

PubMed

Huang, Lei; Ernstoff, Alexi; Fantke, Peter; Csiszar, Susan A; Jolliet, Olivier

2017-01-01

Exposure to chemicals in consumer products has been gaining increasing attention, with multiple studies showing that near-field exposures from products is high compared to far-field exposures. Regarding the numerous chemical-product combinations, there is a need for an overarching review of models able to quantify the multiple transfers of chemicals from products used near-field to humans. The present review therefore aims at an in-depth overview of modeling approaches for near-field chemical release and human exposure pathways associated with consumer products. It focuses on lower-tier, mechanistic models suitable for life cycle assessments (LCA), chemical alternative assessment (CAA) and high-throughput screening risk assessment (HTS). Chemicals in a product enter the near-field via a defined "compartment of entry", are transformed or transferred to adjacent compartments, and eventually end in a "human receptor compartment". We first focus on models of physical mass transfers from the product to 'near-field' compartments. For transfers of chemicals from article interior, adequate modeling of in-article diffusion and of partitioning between article surface and air/skin/food is key. Modeling volatilization and subsequent transfer to the outdoor is crucial for transfers of chemicals used in the inner space of appliances, on object surfaces or directly emitted to indoor air. For transfers from skin surface, models need to reflect the competition between dermal permeation, volatilization and fraction washed-off. We then focus on transfers from the 'near-field' to 'human' compartments, defined as respiratory tract, gastrointestinal tract and epidermis, for which good estimates of air concentrations, non-dietary ingestion parameters and skin permeation are essential, respectively. We critically characterize for each exposure pathway the ability of models to estimate near-field transfers and to best inform LCA, CAA and HTS, summarizing the main characteristics of the

Mapping the patent landscape of synthetic biology for fine chemical production pathways.

PubMed

Carbonell, Pablo; Gök, Abdullah; Shapira, Philip; Faulon, Jean-Loup

2016-09-01

A goal of synthetic biology bio-foundries is to innovate through an iterative design/build/test/learn pipeline. In assessing the value of new chemical production routes, the intellectual property (IP) novelty of the pathway is important. Exploratory studies can be carried using knowledge of the patent/IP landscape for synthetic biology and metabolic engineering. In this paper, we perform an assessment of pathways as potential targets for chemical production across the full catalogue of reachable chemicals in the extended metabolic space of chassis organisms, as computed by the retrosynthesis-based algorithm RetroPath. Our database for reactions processed by sequences in heterologous pathways was screened against the PatSeq database, a comprehensive collection of more than 150M sequences present in patent grants and applications. We also examine related patent families using Derwent Innovations. This large-scale computational study provides useful insights into the IP landscape of synthetic biology for fine and specialty chemicals production. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

The Ex Vivo Eye Irritation Test as an alternative test method for serious eye damage/eye irritation.

PubMed

Spöler, Felix; Kray, Oya; Kray, Stefan; Panfil, Claudia; Schrage, Norbert F

2015-07-01

Ocular irritation testing is a common requirement for the classification, labelling and packaging of chemicals (substances and mixtures). The in vivo Draize rabbit eye test (OECD Test Guideline 405) is considered to be the regulatory reference method for the classification of chemicals according to their potential to induce eye injury. In the Draize test, chemicals are applied to rabbit eyes in vivo, and changes are monitored over time. If no damage is observed, the chemical is not categorised. Otherwise, the classification depends on the severity and reversibility of the damage. Alternative test methods have to be designed to match the classifications from the in vivo reference method. However, observation of damage reversibility is usually not possible in vitro. Within the present study, a new organotypic method based on rabbit corneas obtained from food production is demonstrated to close this gap. The Ex Vivo Eye Irritation Test (EVEIT) retains the full biochemical activity of the corneal epithelium, epithelial stem cells and endothelium. This permits the in-depth analysis of ocular chemical trauma beyond that achievable by using established in vitro methods. In particular, the EVEIT is the first test to permit the direct monitoring of recovery of all corneal layers after damage. To develop a prediction model for the EVEIT that is comparable to the GHS system, 37 reference chemicals were analysed. The experimental data were used to derive a three-level potency ranking of eye irritation and corrosion that best fits the GHS categorisation. In vivo data available in the literature were used for comparison. When compared with GHS classification predictions, the overall accuracy of the three-level potency ranking was 78%. The classification of chemicals as irritating versus non-irritating resulted in 96% sensitivity, 91% specificity and 95% accuracy. 2015 FRAME.

Record of Some Chemical Residues in Poultry Products

ERIC Educational Resources Information Center

Stadelman, W. J.

1973-01-01

How pesticides, polychlorinated biphenyls, and heavy metals might get into poultry meat or eggs is reviewed. Several case studies where chemicals were found in poultry products are discussed. It can be concluded that the poultry industry is striving and generally succeeding in producing safe and nutritious meat and eggs. (Author/EB)

An efficient matrix product operator representation of the quantum chemical Hamiltonian

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keller, Sebastian, E-mail: sebastian.keller@phys.chem.ethz.ch; Reiher, Markus, E-mail: markus.reiher@phys.chem.ethz.ch; Dolfi, Michele, E-mail: dolfim@phys.ethz.ch

We describe how to efficiently construct the quantum chemical Hamiltonian operator in matrix product form. We present its implementation as a density matrix renormalization group (DMRG) algorithm for quantum chemical applications. Existing implementations of DMRG for quantum chemistry are based on the traditional formulation of the method, which was developed from the point of view of Hilbert space decimation and attained higher performance compared to straightforward implementations of matrix product based DMRG. The latter variationally optimizes a class of ansatz states known as matrix product states, where operators are correspondingly represented as matrix product operators (MPOs). The MPO construction schememore » presented here eliminates the previous performance disadvantages while retaining the additional flexibility provided by a matrix product approach, for example, the specification of expectation values becomes an input parameter. In this way, MPOs for different symmetries — abelian and non-abelian — and different relativistic and non-relativistic models may be solved by an otherwise unmodified program.« less

Micromachined chemical jet dispenser

DOEpatents

Swierkowski, S.P.

1999-03-02

A dispenser is disclosed for chemical fluid samples that need to be precisely ejected in size, location, and time. The dispenser is a micro-electro-mechanical systems (MEMS) device fabricated in a bonded silicon wafer and a substrate, such as glass or silicon, using integrated circuit-like fabrication technology which is amenable to mass production. The dispensing is actuated by ultrasonic transducers that efficiently produce a pressure wave in capillaries that contain the chemicals. The 10-200 {micro}m diameter capillaries can be arranged to focus in one spot or may be arranged in a larger dense linear array (ca. 200 capillaries). The dispenser is analogous to some ink jet print heads for computer printers but the fluid is not heated, thus not damaging certain samples. Major applications are in biological sample handling and in analytical chemical procedures such as environmental sample analysis, medical lab analysis, or molecular biology chemistry experiments. 4 figs.

Production of bulk chemicals via novel metabolic pathways in microorganisms.

PubMed

Shin, Jae Ho; Kim, Hyun Uk; Kim, Dong In; Lee, Sang Yup

2013-11-01

Metabolic engineering has been playing important roles in developing high performance microorganisms capable of producing various chemicals and materials from renewable biomass in a sustainable manner. Synthetic and systems biology are also contributing significantly to the creation of novel pathways and the whole cell-wide optimization of metabolic performance, respectively. In order to expand the spectrum of chemicals that can be produced biotechnologically, it is necessary to broaden the metabolic capacities of microorganisms. Expanding the metabolic pathways for biosynthesizing the target chemicals requires not only the enumeration of a series of known enzymes, but also the identification of biochemical gaps whose corresponding enzymes might not actually exist in nature; this issue is the focus of this paper. First, pathway prediction tools, effectively combining reactions that lead to the production of a target chemical, are analyzed in terms of logics representing chemical information, and designing and ranking the proposed metabolic pathways. Then, several approaches for potentially filling in the gaps of the novel metabolic pathway are suggested along with relevant examples, including the use of promiscuous enzymes that flexibly utilize different substrates, design of novel enzymes for non-natural reactions, and exploration of hypothetical proteins. Finally, strain optimization by systems metabolic engineering in the context of novel metabolic pathways constructed is briefly described. It is hoped that this review paper will provide logical ways of efficiently utilizing 'big' biological data to design and develop novel metabolic pathways for the production of various bulk chemicals that are currently produced from fossil resources. Copyright © 2012 Elsevier Inc. All rights reserved.

Model framework for integrating multiple exposure pathways to chemicals in household cleaning products.

PubMed

Shin, H-M; McKone, T E; Bennett, D H

2017-07-01

We present a screening-level exposure-assessment method which integrates exposure from all plausible exposure pathways as a result of indoor residential use of cleaning products. The exposure pathways we considered are (i) exposure to a user during product use via inhalation and dermal, (ii) exposure to chemical residues left on clothing, (iii) exposure to all occupants from the portion released indoors during use via inhalation and dermal, and (iv) exposure to the general population due to down-the-drain disposal via inhalation and ingestion. We use consumer product volatilization models to account for the chemical fractions volatilized to air (f volatilized ) and disposed down the drain (f down-the-drain ) during product use. For each exposure pathway, we use a fate and exposure model to estimate intake rates (iR) in mg/kg/d. Overall, the contribution of the four exposure pathways to the total exposure varies by the type of cleaning activities and with chemical properties. By providing a more comprehensive exposure model and by capturing additional exposures from often-overlooked exposure pathways, our method allows us to compare the relative contribution of various exposure routes and could improve high-throughput exposure assessment for chemicals in cleaning products. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of neurological damage on production of formulaic language

PubMed Central

Sidtis, D.; Canterucci, G.; Katsnelson, D.

2014-01-01

Early studies reported preserved formulaic language in left hemisphere damaged subjects and reduced incidence of formulaic expressions in the conversational speech of stroke patients with right hemispheric damage. Clinical observations suggest a possible role also of subcortical nuclei. This study examined formulaic language in the spontaneous speech of stroke patients with left, right, or subcortical damage. Four subjects were interviewed and their speech samples compared to normal speakers. Raters classified formulaic expressions as speech formulae, fillers, sentence stems, and proper nouns. Results demonstrated that brain damage affected novel and formulaic language competence differently, with a significantly smaller proportion of formulaic expressions in subjects with right or subcortical damage compared to left hemisphere damaged or healthy speakers. These findings converge with previous studies that support the proposal of a right hemisphere/subcortical circuit in the management of formulaic expressions, based on a dual-process model of language incorporating novel and formulaic language use. PMID:19382014

US adult tobacco users' absolute harm perceptions of traditional and alternative tobacco products, information-seeking behaviors, and (mis)beliefs about chemicals in tobacco products.

PubMed

Bernat, Jennifer K; Ferrer, Rebecca A; Margolis, Katherine A; Blake, Kelly D

2017-08-01

Harm perceptions about tobacco products may influence initiation, continued use, and cessation efforts. We assessed associations between adult traditional tobacco product use and absolute harm perceptions of traditional and alternative tobacco products. We also described the topics individuals looked for during their last search for information, their beliefs about chemicals in cigarettes/cigarette smoke, and how both relate to harm perceptions. We ran multivariable models with jackknife replicate weights to analyze data from the 2015 administration of the National Cancer Institute's Health Information National Trends Survey (N=3376). Compared to never users, individuals reported lower perceived levels of harm for products they use. Among current tobacco users, ethnicity, thinking about chemicals in tobacco, and information-seeking were all factors associated with tobacco product harm perceptions. In the full sample, some respondents reported searching for information about health effects and cessation and held misperceptions about the source of chemicals in tobacco. This study fills a gap in the literature by assessing the absolute harm perceptions of a variety of traditional and alternative tobacco products. Harm perceptions vary among tobacco products, and the relationship among tobacco use, information seeking, thoughts about chemicals in tobacco products, and harm perceptions is complex. Data suggest that some individuals search for information about health effects and cessation and hold misperceptions about chemicals in tobacco products. Future inquiry could seek to understand the mechanisms that contribute to forming harm perceptions and beliefs about chemicals in tobacco products. Published by Elsevier Ltd.

15 CFR 714.3 - Advance declaration requirements for additionally planned production of Schedule 3 chemicals.

Code of Federal Regulations, 2013 CFR

2013-01-01

... a Schedule 3 chemical above the declaration threshold; (ii) You plan to produce at a plant declared...; (iii) You plan to increase the production of a Schedule 3 chemical by declared plants on your plant... production of a Schedule 3 chemical at a declared plant site to an amount above the upper limit of the range...

15 CFR 714.3 - Advance declaration requirements for additionally planned production of Schedule 3 chemicals.

Code of Federal Regulations, 2012 CFR

2012-01-01

... a Schedule 3 chemical above the declaration threshold; (ii) You plan to produce at a plant declared...; (iii) You plan to increase the production of a Schedule 3 chemical by declared plants on your plant... production of a Schedule 3 chemical at a declared plant site to an amount above the upper limit of the range...

15 CFR 714.3 - Advance declaration requirements for additionally planned production of Schedule 3 chemicals.

Code of Federal Regulations, 2014 CFR

2014-01-01

... a Schedule 3 chemical above the declaration threshold; (ii) You plan to produce at a plant declared...; (iii) You plan to increase the production of a Schedule 3 chemical by declared plants on your plant... production of a Schedule 3 chemical at a declared plant site to an amount above the upper limit of the range...

Trends in Exposure to Chemicals in Personal Care and Consumer Products.

PubMed

Calafat, Antonia M; Valentin-Blasini, Liza; Ye, Xiaoyun

2015-12-01

Synthetic organic chemicals can be used in personal care and consumer products. Data on potential human health effects of these chemicals are limited-sometimes even contradictory-but because several of these chemicals are toxic in experimental animals, alternative compounds are entering consumer markets. Nevertheless, limited information exists on consequent exposure trends to both the original chemicals and their replacements. Biomonitoring (measuring concentrations of chemicals or their metabolites in people) provides invaluable information for exposure assessment. We use phthalates and bisphenol A-known industrial chemicals-and organophosphate insecticides as case studies to show exposure trends to these chemicals and their replacements (e.g., other phthalates, non-phthalate plasticizers, various bisphenols, pyrethroid insecticides) among the US general population. We compare US trends to national trends from Canada and Germany. Exposure to the original compounds is still prevalent among these general populations, but exposures to alternative chemicals may be increasing.

Insights into biogenic and chemical production of inorganic nanomaterials and nanostructures.

PubMed

Faramarzi, Mohammad Ali; Sadighi, Armin

2013-03-01

The synthesis of inorganic nanomaterials and nanostructures by the means of diverse physical, chemical, and biological principles has been developed in recent decades. The nanoscale materials and structures creation continue to be an active area of researches due to the exciting properties of the resulting nanomaterials and their innovative applications. Despite physical and chemical approaches which have been used for a long time to produce nanomaterials, biological resources as green candidates that can replace old production methods have been focused in recent years to generate various inorganic nanoparticles (NPs) or other nanoscale structures. Cost-effective, eco-friendly, energy efficient, and nontoxic produced nanomaterials using diverse biological entities have been received increasing attention in the last two decades in contrast to physical and chemical methods owe using toxic solvents, generate unwanted by-products, and high energy consumption which restrict the popularity of these ways employed in nanometric science and engineering. In this review, the biosynthesis of gold, silver, gold-silver alloy, magnetic, semiconductor nanocrystals, silica, zirconia, titania, palladium, bismuth, selenium, antimony sulfide, and platinum NPs, using bacteria, actinomycetes, fungi, yeasts, plant extracts and also informational bio-macromolecules including proteins, polypeptides, DNA, and RNA have been reported extensively to mention the current status of the biological inorganic nanomaterial production. In other hand, two well-known wet chemical techniques, namely chemical reduction and sol-gel methods, used to produce various types of nanocrystalline powders, metal oxides, and hybrid organic-inorganic nanomaterials have presented. Copyright © 2012 Elsevier B.V. All rights reserved.

Triamcinolone hexacetonide protects against fibrillation and osteophyte formation following chemically induced articular cartilage damage.

PubMed

Williams, J M; Brandt, K D

1985-11-01

Although corticosteroids have been shown to cause articular cartilage degeneration, recent studies of experimentally induced osteoarthritis indicate that under certain conditions they may protect against cartilage damage and osteophyte formation. The present study examines the in vivo effect of triamcinolone hexacetonide on the degeneration of articular cartilage which occurs following intraarticular injection of sodium iodoacetate. Three weeks after a single injection of iodoacetate into the knees of guinea pigs, ipsilateral femoral condylar cartilage exhibited fibrillation, loss of staining with Safranin O, depletion of chondrocytes, and prominent osteophytes. In striking contrast, when triamcinolone hexacetonide was injected into the ipsilateral knee 24 hours after the intraarticular injection of iodoacetate, fibrillation was noted in only 1 of 6 samples, osteophytes were much less prominent, pericellular staining with Safranin O persisted, and cell loss was less extensive. Knees of animals which received only one-tenth as much intraarticular triamcinolone hexacetonide after the iodoacetate injection also exhibited marked reduction in size and extent of osteophytes. However, the degree of fibrillation, loss of Safranin O staining, and chondrocyte depletion was similar to that observed in animals injected with iodoacetate but not treated with intraarticular steroid. No apparent morphologic or histochemical changes were observed after intraarticular injection of the steroid preparation alone. Thus, triamcinolone hexacetonide produced a marked, dose-dependent protective effect in this model of chemically induced articular cartilage damage.

Enabling continuous-flow chemistry in microstructured devices for pharmaceutical and fine-chemical production.

PubMed

Kockmann, Norbert; Gottsponer, Michael; Zimmermann, Bertin; Roberge, Dominique M

2008-01-01

Microstructured devices offer unique transport capabilities for rapid mixing, enhanced heat and mass transfer and can handle small amounts of dangerous or unstable materials. The integration of reaction kinetics into fluid dynamics and transport phenomena is essential for successful application from process design in laboratory to chemical production. Strategies to implement production campaigns up to tons of pharmaceutical chemicals are discussed, based on Lonza projects.

Metabolic engineering of Saccharomyces cerevisiae for production of very long chain fatty acid-derived chemicals.

PubMed

Yu, Tao; Zhou, Yongjin J; Wenning, Leonie; Liu, Quanli; Krivoruchko, Anastasia; Siewers, Verena; Nielsen, Jens; David, Florian

2017-05-26

Production of chemicals and biofuels through microbial fermentation is an economical and sustainable alternative for traditional chemical synthesis. Here we present the construction of a Saccharomyces cerevisiae platform strain for high-level production of very-long-chain fatty acid (VLCFA)-derived chemicals. Through rewiring the native fatty acid elongation system and implementing a heterologous Mycobacteria FAS I system, we establish an increased biosynthesis of VLCFAs in S. cerevisiae. VLCFAs can be selectively modified towards the fatty alcohol docosanol (C 22 H 46 O) by expressing a specific fatty acid reductase. Expression of this enzyme is shown to impair cell growth due to consumption of VLCFA-CoAs. We therefore implement a dynamic control strategy for separating cell growth from docosanol production. We successfully establish high-level and selective docosanol production of 83.5 mg l -1 in yeast. This approach will provide a universal strategy towards the production of similar high value chemicals in a more scalable, stable and sustainable manner.

Use of bacterial co-cultures for the efficient production of chemicals.

PubMed

Jones, J Andrew; Wang, Xin

2017-12-02

The microbial production of chemicals has traditionally relied on a single engineered microbe to enable the complete bioconversion of substrate to final product. Recently, a growing fraction of research has transitioned towards employing a modular co-culture engineering strategy using multiple microbes growing together to facilitate a divide-and-conquer approach for chemical biosynthesis. Here, we review key success stories that leverage the unique advantages of co-culture engineering, while also addressing the critical concerns that will limit the wide-spread implementation of this technology. Future studies that address the need to monitor and control the population dynamics of each strain module, while maintaining robust flux routes towards a wide range of desired products will lead the efforts to realize the true potential of co-culture engineering. Copyright © 2017 Elsevier Ltd. All rights reserved.

A general strategy for the chemical aspects of the safety assessment of extractables and leachables in pharmaceutical drug products: the chemical assessment triad.

PubMed

Jenke, Dennis

2012-01-01

During the course of their manufacturing, storage, and administration, pharmaceutical drug products come in contact with materials, components, and systems. Such contact may result in an interaction between the drug product and these entities. One such interaction is the migration of substances from these entities and into the drug product, which is of concern due to the potential toxicity of the migrating substances. In order to properly assess the risk and manage the hazard posed by migratory substances, it is necessary to establish the identities of the migratory substances and the levels to which they will accumulate in the finished drug product, as these two pieces of information establish the hazard posed by an individual substance and the magnitude of the patient exposure (dose). The process by which migrating compounds are discovered and identified, and by which their accumulation levels in a finished drug product are established, is termed chemical assessment. Because the development of a finished drug product is a long and complicated process, chemical assessment is most typically not a single action but rather a series of actions that together establish a process of risk management. It is the purpose of this manuscript to establish a high-level strategy, illustrated in the chemical assessment triad, which can be applied to such a risk management process. During the course of their manufacturing, storage, and administration, pharmaceutical drug products come in contact with materials, components, and systems. Such contact may result in an interaction between the drug product and these entities. One such interaction is the migration of substances from these entities and into the drug product, which is of concern due to the potential toxicity of the migrating substances. It is the purpose of this manuscript to outline a high-level strategy, illustrated in the chemical assessment triad, to chemically establish the safety risk related to the migrating

Analysis of the Precursors, Simulants and Degradation Products of Chemical Warfare Agents.

PubMed

Witkiewicz, Zygfryd; Neffe, Slawomir; Sliwka, Ewa; Quagliano, Javier

2018-09-03

Recent advances in analysis of precursors, simulants and degradation products of chemical warfare agents (CWA) are reviewed. Fast and reliable analysis of precursors, simulants and CWA degradation products is extremely important at a time, when more and more terrorist groups and radical non-state organizations use or plan to use chemical weapons to achieve their own psychological, political and military goals. The review covers the open source literature analysis after the time, when the chemical weapons convention had come into force (1997). The authors stated that during last 15 years increased number of laboratories are focused not only on trace analysis of CWA (mostly nerve and blister agents) in environmental and biological samples, but the growing number of research are devoted to instrumental analysis of precursors and degradation products of these substances. The identification of low-level concentration of CWA degradation products is often more important and difficult than the original CWA, because of lower level of concentration and a very large number of compounds present in environmental and biological samples. Many of them are hydrolysis products and are present in samples in the ionic form. For this reason, two or three instrumental methods are used to perform a reliable analysis of these substances.

C1-carbon sources for chemical and fuel production by microbial gas fermentation.

PubMed

Dürre, Peter; Eikmanns, Bernhard J

2015-12-01

Fossil resources for production of fuels and chemicals are finite and fuel use contributes to greenhouse gas emissions and global warming. Thus, sustainable fuel supply, security, and prices necessitate the implementation of alternative routes to the production of chemicals and fuels. Much attention has been focussed on use of cellulosic material, particularly through microbial-based processes. However, this is still costly and proving challenging, as are catalytic routes to biofuels from whole biomass. An alternative strategy is to directly capture carbon before incorporation into lignocellulosic biomass. Autotrophic acetogenic, carboxidotrophic, and methanotrophic bacteria are able to capture carbon as CO, CO2, or CH4, respectively, and reuse that carbon in products that displace their fossil-derived counterparts. Thus, gas fermentation represents a versatile industrial platform for the sustainable production of commodity chemicals and fuels from diverse gas resources derived from industrial processes, coal, biomass, municipal solid waste (MSW), and extracted natural gas. Copyright © 2015 Elsevier Ltd. All rights reserved.

Aeroallergens Induce Reactive Oxygen Species Production and DNA Damage and Dampen Antioxidant Responses in Bronchial Epithelial Cells.

PubMed

Chan, Tze Khee; Tan, W S Daniel; Peh, Hong Yong; Wong, W S Fred

2017-07-01

Exposure to environmental allergens is a major risk factor for asthma development. Allergens possess proteolytic activity that is capable of disrupting the airway epithelium. Although there is increasing evidence pointing to asthma as an epithelial disease, the underlying mechanism that drives asthma has not been fully elucidated. In this study, we investigated the direct DNA damage potential of aeroallergens on human bronchial epithelial cells and elucidated the mechanisms mediating the damage. Human bronchial epithelial cells, BEAS-2B, directly exposed to house dust mites (HDM) resulted in enhanced DNA damage, as measured by the CometChip and the staining of DNA double-strand break marker, γH2AX. HDM stimulated cellular reactive oxygen species production, increased mitochondrial oxidative stress, and promoted nitrosative stress. Notably, expression of nuclear factor erythroid 2-related factor 2-dependent antioxidant genes was reduced immediately after HDM exposure, suggesting that HDM altered antioxidant responses. HDM exposure also reduced cell proliferation and induced cell death. Importantly, HDM-induced DNA damage can be prevented by the antioxidants glutathione and catalase, suggesting that HDM-induced reactive oxygen and nitrogen species can be neutralized by antioxidants. Mechanistic studies revealed that HDM-induced cellular injury is NADPH oxidase (NOX)-dependent, and apocynin, a NOX inhibitor, protected cells from double-strand breaks induced by HDM. Our results show that direct exposure of bronchial epithelial cells to HDM leads to the production of reactive oxygen and nitrogen species that damage DNA and induce cytotoxicity. Antioxidants and NOX inhibitors can prevent HDM-induced DNA damage, revealing a novel role for antioxidants and NOX inhibitors in mitigating allergic airway disease. Copyright © 2017 by The American Association of Immunologists, Inc.

Glycation products in infant formulas: chemical, analytical and physiological aspects.

PubMed

Pischetsrieder, Monika; Henle, Thomas

2012-04-01

Infant formulas are milk-based products, which are adapted to the composition of human milk. To ensure microbiological safety and long shelf life, infant formulas usually undergo rigid heat treatment. As a consequence of the special composition and the heat regimen, infant formulas are more prone to thermally induced degradation reactions than regular milk products. Degradation reactions observed during milk processing comprise lactosylation yielding the Amadori product lactulosyllysine, the formation of advanced glycation end products (AGEs), and protein-free sugar degradation products, as well as protein or lipid oxidation. Several methods have been developed to estimate the heat impact applied during the manufacturing of infant formulas, including indirect methods such as fluorescence analysis as well as the analysis of defined reaction products. Most studies confirm a higher degree of damage in infant formulas compared to regular milk products. Differences between various types of infant formulas, such as liquid, powdered or hypoallergenic formulas depend on the analyzed markers and brands. A considerable portion of protein degradation products in infant formulas can be avoided when process parameters and the quality of the ingredients are carefully controlled. The nutritional consequences of thermal degradation products in infant formulas are largely unknown.

Radiation damage of gallium arsenide production cells

NASA Technical Reports Server (NTRS)

Mardesich, N.; Joslin, D.; Garlick, J.; Lillington, D.; Gillanders, M.; Cavicchi, B.; Scott-Monck, J.; Kachare, R.; Anspaugh, B.

1987-01-01

High efficiency liquid phase epitaxy (LPE) gallium arsenide cells were irradiated with 1 Mev electrons up to fluences of 1 times 10 to the 16th power cm-2. Measurements of spectral response and dark and illuminated I-V data were made at each fluence and then, using computer codes, the experimental data was fitted to gallium arsenide cell models. In this way it was possible to determine the extent of the damage, and hence damage coefficients in both the emitter and base of the cell.

Yellow phosphorus process to convert toxic chemicals to non-toxic products

DOEpatents

Chang, S.G.

1994-07-26

The present invention relates to a process for generating reactive species for destroying toxic chemicals. This process first contacts air or oxygen with aqueous emulsions of molten yellow phosphorus. This contact results in rapid production of abundant reactive species such as O, O[sub 3], PO, PO[sub 2], etc. A gaseous or liquid aqueous solution organic or inorganic chemicals is next contacted by these reactive species to reduce the concentration of toxic chemical and result in a non-toxic product. The final oxidation product of yellow phosphorus is phosphoric acid of a quality which can be recovered for commercial use. A process is developed such that the byproduct, phosphoric acid, is obtained without contamination of toxic species in liquids treated. A gas stream containing ozone without contamination of phosphorus containing species is also obtained in a simple and cost-effective manner. This process is demonstrated to be effective for destroying many types of toxic organic, or inorganic, compounds, including polychlorinated biphenyls (PCB), aromatic chlorides, amines, alcohols, acids, nitro aromatics, aliphatic chlorides, polynuclear aromatic compounds (PAH), dyes, pesticides, sulfides, hydroxyamines, ureas, dithionates and the like. 20 figs.

Yellow phosphorus process to convert toxic chemicals to non-toxic products

DOEpatents

Chang, Shih-Ger

1994-01-01

The present invention relates to a process for generating reactive species for destroying toxic chemicals. This process first contacts air or oxygen with aqueous emulsions of molten yellow phosphorus. This contact results in rapid production of abundant reactive species such as O, O.sub.3, PO, PO.sub.2, etc. A gaseous or liquid aqueous solution organic or inorganic chemicals is next contacted by these reactive species to reduce the concentration of toxic chemical and result in a non-toxic product. The final oxidation product of yellow phosphorus is phosphoric acid of a quality which can be recovered for commercial use. A process is developed such that the byproduct, phosphoric acid, is obtained without contamination of toxic species in liquids treated. A gas stream containing ozone without contamination of phosphorus containing species is also obtained in a simple and cost-effective manner. This process is demonstrated to be effective for destroying many types of toxic organic, or inorganic, compounds, including polychlorinated biphenyls (PCB), aromatic chlorides, amines, alcohols, acids, nitro aromatics, aliphatic chlorides, polynuclear aromatic compounds (PAH), dyes, pesticides, sulfides, hydroxyamines, ureas, dithionates and the like.

Unrepaired DNA damage in macrophages causes elevation of particulate matter- induced airway inflammatory response.

PubMed

Luo, Man; Bao, Zhengqiang; Xu, Feng; Wang, Xiaohui; Li, Fei; Li, Wen; Chen, Zhihua; Ying, Songmin; Shen, Huahao

2018-04-14

The inflammatory cascade can be initiated with the recognition of damaged DNA. Macrophages play an essential role in particulate matter (PM)-induced airway inflammation. In this study, we aim to explore the PM induced DNA damage response of macrophages and its function in airway inflammation. The DNA damage response and inflammatory response were assessed using bone marrow-derived macrophages following PM treatment and mouse model instilled intratracheally with PM. We found that PM induced significant DNA damage both in vitro and in vivo and simultaneously triggered a rapid DNA damage response, represented by nuclear RPA, 53BP1 and γH2AX foci formation. Genetic ablation or chemical inhibition of the DNA damage response sensor amplified the production of cytokines including Cxcl1, Cxcl2 and Ifn-γ after PM stimulation in bone marrow-derived macrophages. Similar to that seen in vitro , mice with myeloid-specific deletion of RAD50 showed higher levels of airway inflammation in response to the PM challenge, suggesting a protective role of DNA damage sensor during inflammation. These data demonstrate that PM exposure induces DNA damage and activation of DNA damage response sensor MRN complex in macrophages. Disruption of MRN complex lead to persistent, unrepaired DNA damage that causes elevated inflammatory response.

Advances in metabolic engineering of yeast Saccharomyces cerevisiae for production of chemicals.

PubMed

Borodina, Irina; Nielsen, Jens

2014-05-01

Yeast Saccharomyces cerevisiae is an important industrial host for production of enzymes, pharmaceutical and nutraceutical ingredients and recently also commodity chemicals and biofuels. Here, we review the advances in modeling and synthetic biology tools and how these tools can speed up the development of yeast cell factories. We also present an overview of metabolic engineering strategies for developing yeast strains for production of polymer monomers: lactic, succinic, and cis,cis-muconic acids. S. cerevisiae has already firmly established itself as a cell factory in industrial biotechnology and the advances in yeast strain engineering will stimulate development of novel yeast-based processes for chemicals production. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chemoinformatic expedition of the chemical space of fungal products.

PubMed

González-Medina, Mariana; Prieto-Martínez, Fernando D; Naveja, J Jesús; Méndez-Lucio, Oscar; El-Elimat, Tamam; Pearce, Cedric J; Oberlies, Nicholas H; Figueroa, Mario; Medina-Franco, José L

2016-08-01

Fungi are valuable resources for bioactive secondary metabolites. However, the chemical space of fungal secondary metabolites has been studied only on a limited basis. Herein, we report a comprehensive chemoinformatic analysis of a unique set of 207 fungal metabolites isolated and characterized in a USA National Cancer Institute funded drug discovery project. Comparison of the molecular complexity of the 207 fungal metabolites with approved anticancer and nonanticancer drugs, compounds in clinical studies, general screening compounds and molecules Generally Recognized as Safe revealed that fungal metabolites have high degree of complexity. Molecular fingerprints showed that fungal metabolites are as structurally diverse as other natural products and have, in general, drug-like physicochemical properties. Fungal products represent promising candidates to expand the medicinally relevant chemical space. This work is a significant expansion of an analysis reported years ago for a smaller set of compounds (less than half of the ones included in the present work) from filamentous fungi using different structural properties.

The Efficient Clade: Lactic Acid Bacteria for Industrial Chemical Production.

PubMed

Sauer, Michael; Russmayer, Hannes; Grabherr, Reingard; Peterbauer, Clemens K; Marx, Hans

2017-08-01

Lactic acid bacteria are well known to be beneficial for food production and, as probiotics, they are relevant for many aspects of health. However, their potential as cell factories for the chemical industry is only emerging. Many physiological traits of these microorganisms, evolved for optimal growth in their niche, are also valuable in an industrial context. Here, we illuminate these features and describe why the distinctive adaptation of lactic acid bacteria is particularly useful when developing a microbial process for chemical production from renewable resources. High carbon uptake rates with low biomass formation combined with strictly regulated simple metabolic pathways, leading to a limited number of metabolites, are among the key factors defining their success in both nature and industry. Copyright © 2017 Elsevier Ltd. All rights reserved.

Damage to the microbial cell membrane during pyrolytic sugar utilization and strategies for increasing resistance.

PubMed

Jin, Tao; Rover, Marjorie R; Petersen, Elspeth M; Chi, Zhanyou; Smith, Ryan G; Brown, Robert C; Wen, Zhiyou; Jarboe, Laura R

2017-09-01

Lignocellulosic biomass is an appealing feedstock for the production of biorenewable fuels and chemicals, and thermochemical processing is a promising method for depolymerizing it into sugars. However, trace compounds in this pyrolytic sugar syrup are inhibitory to microbial biocatalysts. This study demonstrates that hydrophobic inhibitors damage the cell membrane of ethanologenic Escherichia coli KO11+lgk. Adaptive evolution was employed to identify design strategies for improving pyrolytic sugar tolerance and utilization. Characterization of the resulting evolved strain indicates that increased resistance to the membrane-damaging effects of the pyrolytic sugars can be attributed to a glutamine to leucine mutation at position 29 of carbon storage regulator CsrA. This single amino acid change is sufficient for decreasing EPS protein production and increasing membrane integrity when exposed to pyrolytic sugars.

Production of solar chemicals: gaining selectivity with hybrid molecule/semiconductor assemblies.

PubMed

Hennessey, Seán; Farràs, Pau

2018-05-29

Research on the production of solar fuels and chemicals has rocketed over the past decade, with a wide variety of systems proposed to harvest solar energy and drive chemical reactions. In this Feature Article we have focused on hybrid molecule/semiconductor assemblies in both powder and supported materials, summarising recent systems and highlighting the enormous possibilities offered by such assemblies to carry out highly demanding chemical reactions with industrial impact. Of relevance is the higher selectivity obtained in visible light-driven organic transformations when using molecular catalysts compared to photocatalytic materials.

Chemical properties and colors of fermenting materials in salmon fish sauce production.

PubMed

Nakano, Mitsutoshi; Sagane, Yoshimasa; Koizumi, Ryosuke; Nakazawa, Yozo; Yamazaki, Masao; Watanabe, Toshihiro; Takano, Katsumi; Sato, Hiroaki

2018-02-01

This data article reports the chemical properties (moisture, pH, salinity, and soluble solid content) and colors of fermenting materials in salmon fish sauce products. The fish sauce was produced by mixing salt with differing proportions of raw salmon materials and fermenting for three months; the salmon materials comprised flesh, viscera, an inedible portion, and soft roe. Chemical properties and colors of the unrefined fish sauce ( moromi ), and the refined fish sauce, were analyzed at one, two, and three months following the start of fermentation. Data determined for all products are provided in table format.

Composition and production rate of pharmaceutical and chemical waste from Xanthi General Hospital in Greece

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voudrias, Evangelos, E-mail: voudrias@env.duth.gr; Goudakou, Lambrini; Kermenidou, Marianthi

2012-07-15

Highlights: Black-Right-Pointing-Pointer We studied pharmaceutical and chemical waste production in a Greek hospital. Black-Right-Pointing-Pointer Pharmaceutical waste comprised 3.9% w/w of total hazardous medical waste. Black-Right-Pointing-Pointer Unit production rate for total pharmaceutical waste was 12.4 {+-} 3.90 g/patient/d. Black-Right-Pointing-Pointer Chemical waste comprised 1.8% w/w of total hazardous medical waste. Black-Right-Pointing-Pointer Unit production rate for total chemical waste was 5.8 {+-} 2.2 g/patient/d. - Abstract: The objective of this work was to determine the composition and production rates of pharmaceutical and chemical waste produced by Xanthi General Hospital in Greece (XGH). This information is important to design and cost management systems formore » pharmaceutical and chemical waste, for safety and health considerations and for assessing environmental impact. A total of 233 kg pharmaceutical and 110 kg chemical waste was collected, manually separated and weighed over a period of five working weeks. The total production of pharmaceutical waste comprised 3.9% w/w of the total hazardous medical waste produced by the hospital. Total pharmaceutical waste was classified in three categories, vial waste comprising 51.1%, syringe waste with 11.4% and intravenous therapy (IV) waste with 37.5% w/w of the total. Vial pharmaceutical waste only was further classified in six major categories: antibiotics, digestive system drugs, analgesics, hormones, circulatory system drugs and 'other'. Production data below are presented as average (standard deviation in parenthesis). The unit production rates for total pharmaceutical waste for the hospital were 12.4 (3.90) g/patient/d and 24.6 (7.48) g/bed/d. The respective unit production rates were: (1) for vial waste 6.4 (1.6) g/patient/d and 13 (2.6) g/bed/d, (2) for syringe waste 1.4 (0.4) g/patient/d and 2.8 (0.8) g/bed/d and (3) for IV waste 4.6 (3.0) g/patient/d and 9.2 (5.9) g/bed/d. Total

21 CFR 1310.16 - Exemptions for certain scheduled listed chemical products.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Exemptions for certain scheduled listed chemical products. 1310.16 Section 1310.16 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE... chapter if the Administrator determines that the product cannot be used in the illicit manufacture of a...

Displacement Cascade Damage Production in Metals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stoller, Roger E; Malerba, Lorenzo; Nordlund, Kai

Radiation-induced changes in microstructure and mechanical properties in structural materials are the result of a complex set of physical processes initiated by the collision between an energetic particle (neutron or ion) and an atom in the lattice. This primary damage event is called an atomic displacement cascade. The simplest description of a displacement cascade is to view it as a series of many billiard-ball-like elastic collisions among the atoms in the material. This chapter describes the formation and evolution of this primary radiation damage mechanism to provide an overview of how stable defects are formed by displacement cascades, as wellmore » as the nature and morphology of the defects themselves. The impact of the relevant variables such as cascade energy and irradiation temperature is discussed, and defect formation in different materials is compared.« less

Drug-induced corneal damage.

PubMed

2014-04-01

Corneal damage can have a variety of causes, including infections, chemical splashes, environmental factors (radiation, trauma, contact lenses, etc.), and systemic diseases (genetic, autoimmune, inflammatory, metabolic, etc.). A wide range of drugs can also damage the cornea. The severity of drug-induced corneal changes can range from simple asymptomatic deposits to irreversible, sight-threatening damage. Several factors can influence the onset of corneal lesions. Some factors, such as the dose, are treatment-related, while others such as contact lenses, are patient-related. A variety of mechanisms may be involved, including corneal dryness, changes in the corneal epithelium, impaired wound healing and deposits. Many drugs can damage the cornea through direct contact, after intraocular injection or instillation, including VEGF inhibitors, anti-inflammatory drugs, local anaesthetics, glaucoma drugs, fluoroquinolones, and preservatives. Some systemically administered drugs can also damage the cornea, notably cancer drugs, amiodarone and isotretinoin. Vulnerable patients should be informed of this risk if they are prescribed a drug with the potential to damage the cornea so that they can identify problems in a timely manner. It may be necessary to discontinue the suspect drug when signs and symptoms of corneal damage occur.

16 CFR 1500.231 - Guidance for hazardous liquid chemicals in children's products.

Code of Federal Regulations, 2011 CFR

2011-01-01

... hazardous chemicals, such as mercury, ethylene glycol, diethylene glycol, methanol, methylene chloride... purchasing products for resale, importers, distributors, and retailers obtain assurances from manufacturers... retailers obtain assurances from the manufacturers that liquid-filled children's products do not contain...

[Blocking 1800 MHz mobile phone radiation-induced reactive oxygen species production and DNA damage in lens epithelial cells by noise magnetic fields].

PubMed

Wu, Wei; Yao, Ke; Wang, Kai-jun; Lu, De-qiang; He, Ji-liang; Xu, Li-hong; Sun, Wen-jun

2008-01-01

To investigate whether the exposure to the electromagnetic noise can block reactive oxygen species (ROS) production and DNA damage of lens epithelial cells induced by 1800 MHz mobile phone radiation. The DCFH-DA method and comet assay were used respectively to detect the intracellular ROS and DNA damage of cultured human lens epithelial cells induced by 4 W/kg 1800 MHz mobile phone radiation or/and 2 muT electromagnetic noise for 24 h intermittently. 1800 MHz mobile phone radiation at 4 W/kg for 24 h increased intracellular ROS and DNA damage significantly (P<0.05). However, the ROS level and DNA damage of mobile phone radiation plus noise group were not significant enhanced (P>0.05) as compared to sham exposure group. Electromagnetic noise can block intracellular ROS production and DNA damage of human lens epithelial cells induced by 1800 MHz mobile phone radiation.

Is Allelopathic Activity of Ipomoea murucoides Induced by Xylophage Damage?

PubMed Central

Flores-Palacios, Alejandro; Corona-López, Angélica María; Rios, María Yolanda; Aguilar-Guadarrama, Berenice; Toledo-Hernández, Víctor Hugo; Rodríguez-López, Verónica; Valencia-Díaz, Susana

2015-01-01

Herbivory activates the synthesis of allelochemicals that can mediate plant-plant interactions. There is an inverse relationship between the activity of xylophages and the abundance of epiphytes on Ipomoea murucoides. Xylophagy may modify the branch chemical constitution, which also affects the liberation of allelochemicals with defense and allelopathic properties. We evaluated the bark chemical content and the effect of extracts from branches subjected to treatments of exclusion, mechanical damage and the presence/absence of epiphytes, on the seed germination of the epiphyte Tillandsia recurvata. Principal component analysis showed that branches without any treatment separate from branches subjected to treatments; damaged and excluded branches had similar chemical content but we found no evidence to relate intentional damage with allelopathy; however 1-hexadecanol, a defense volatile compound correlated positively with principal component (PC) 1. The chemical constitution of branches subject to exclusion plus damage or plus epiphytes was similar among them. PC2 indicated that palmitic acid (allelopathic compound) and squalene, a triterpene that attracts herbivore enemies, correlated positively with the inhibition of seed germination of T. recurvata. Inhibition of seed germination of T. recurvata was mainly correlated with the increment of palmitic acid and this compound reached higher concentrations in excluded branches treatments. Then, it is likely that the allelopathic response of I. murucoides would increase to the damage (shade, load) that may be caused by a high load of epiphytes than to damage caused by the xylophages. PMID:26625350

Is Allelopathic Activity of Ipomoea murucoides Induced by Xylophage Damage?

PubMed

Flores-Palacios, Alejandro; Corona-López, Angélica María; Rios, María Yolanda; Aguilar-Guadarrama, Berenice; Toledo-Hernández, Víctor Hugo; Rodríguez-López, Verónica; Valencia-Díaz, Susana

2015-01-01

Herbivory activates the synthesis of allelochemicals that can mediate plant-plant interactions. There is an inverse relationship between the activity of xylophages and the abundance of epiphytes on Ipomoea murucoides. Xylophagy may modify the branch chemical constitution, which also affects the liberation of allelochemicals with defense and allelopathic properties. We evaluated the bark chemical content and the effect of extracts from branches subjected to treatments of exclusion, mechanical damage and the presence/absence of epiphytes, on the seed germination of the epiphyte Tillandsia recurvata. Principal component analysis showed that branches without any treatment separate from branches subjected to treatments; damaged and excluded branches had similar chemical content but we found no evidence to relate intentional damage with allelopathy; however 1-hexadecanol, a defense volatile compound correlated positively with principal component (PC) 1. The chemical constitution of branches subject to exclusion plus damage or plus epiphytes was similar among them. PC2 indicated that palmitic acid (allelopathic compound) and squalene, a triterpene that attracts herbivore enemies, correlated positively with the inhibition of seed germination of T. recurvata. Inhibition of seed germination of T. recurvata was mainly correlated with the increment of palmitic acid and this compound reached higher concentrations in excluded branches treatments. Then, it is likely that the allelopathic response of I. murucoides would increase to the damage (shade, load) that may be caused by a high load of epiphytes than to damage caused by the xylophages.

Recent advances in microbial production of fuels and chemicals using tools and strategies of systems metabolic engineering.

PubMed

Cho, Changhee; Choi, So Young; Luo, Zi Wei; Lee, Sang Yup

2015-11-15

The advent of various systems metabolic engineering tools and strategies has enabled more sophisticated engineering of microorganisms for the production of industrially useful fuels and chemicals. Advances in systems metabolic engineering have been made in overproducing natural chemicals and producing novel non-natural chemicals. In this paper, we review the tools and strategies of systems metabolic engineering employed for the development of microorganisms for the production of various industrially useful chemicals belonging to fuels, building block chemicals, and specialty chemicals, in particular focusing on those reported in the last three years. It was aimed at providing the current landscape of systems metabolic engineering and suggesting directions to address future challenges towards successfully establishing processes for the bio-based production of fuels and chemicals from renewable resources. Copyright © 2014 Elsevier Inc. All rights reserved.

Chemical methods for peptide and protein production.

PubMed

Chandrudu, Saranya; Simerska, Pavla; Toth, Istvan

2013-04-12

Since the invention of solid phase synthetic methods by Merrifield in 1963, the number of research groups focusing on peptide synthesis has grown exponentially. However, the original step-by-step synthesis had limitations: the purity of the final product decreased with the number of coupling steps. After the development of Boc and Fmoc protecting groups, novel amino acid protecting groups and new techniques were introduced to provide high quality and quantity peptide products. Fragment condensation was a popular method for peptide production in the 1980s, but unfortunately the rate of racemization and reaction difficulties proved less than ideal. Kent and co-workers revolutionized peptide coupling by introducing the chemoselective reaction of unprotected peptides, called native chemical ligation. Subsequently, research has focused on the development of novel ligating techniques including the famous click reaction, ligation of peptide hydrazides, and the recently reported α-ketoacid-hydroxylamine ligations with 5-oxaproline. Several companies have been formed all over the world to prepare high quality Good Manufacturing Practice peptide products on a multi-kilogram scale. This review describes the advances in peptide chemistry including the variety of synthetic peptide methods currently available and the broad application of peptides in medicinal chemistry.

Double product and end-organ damage in African and Caucasian men: the SABPA study.

PubMed

Schultz, A J; Schutte, A E; Schutte, R

2013-08-10

Increasing urbanisation in sub-Saharan African countries is causing a rapid increase in cardiovascular disease. Evidence suggests that Africans have higher blood pressures and a higher prevalence of hypertension-related cardiovascular morbidity and mortality, compared to Caucasians. We investigated double product (systolic blood pressure × heart rate), a substantial measure of cardiac workload, as a possible cardiovascular risk factor in African and Caucasian men. The study consisted of 101 urbanised African and 101 Caucasian male school teachers. We measured 24h ambulatory blood pressure and the carotid cross-sectional wall area, and determined left ventricular hypertrophy electrocardiographically by means of the Cornell product. Urinary albumin and creatinine were analysed to obtain the albumin-to-creatinine ratio. Africans had higher 24h, daytime and nighttime systolic- and diastolic blood pressure, heart rate and resultant double product compared to the Caucasians. In addition, markers of end-organ damage, albumin-to-creatinine ratio and left ventricular hypertrophy were higher in the Africans while cross-sectional wall area did not differ. In Africans after single partial and multiple regression analysis, 24h systolic blood pressure, but not double product or heart rate, correlated positively with markers of end-organ damage (cross-sectional wall area: β=0.398, P=0.005; left ventricular hypertrophy: β=0.455, P<0.001; albumin-to-creatinine ratio: β=0.280, P=0.012). No associations were evident in Caucasian men. Double product may not be a good marker of increased cardiovascular risk when compared to systolic blood pressure in African and Caucasian men. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Evaluation of genome damage in subjects occupationally exposed to possible carcinogens.

PubMed

Zeljezic, Davor; Mladinic, Marin; Kopjar, Nevenka; Radulovic, Azra Hursidic

2016-09-01

In occupational exposures, populations are simultaneously exposed to a mixture of chemicals. We aimed to evaluate DNA damage due to possible carcinogen exposure (phenylhydrazine, ethylene oxide, dichloromethane, and 1,2-dichloroethane) in lymphocytes of pharmaceutical industry workers from the same production line. Population comprised 16 subjects (9 females and 7 males) who were exposed to multiple chemicals for 8 months. Genome damage was assessed using alkaline comet assay, micronucleus assay, and comet assay coupled with fluorescent in situ hybridization (comet-FISH). After 8 months of exposure, the issue of irregular use of all available personal protective equipment (PPE) came into light. To decrease the risk of exposure, strict use of PPE was enforced. After 8 months of strict PPE use, micronuclei frequency and comet assay parameters in lymphocytes of pharmaceutical workers significantly decreased compared with prior period of irregular PPE use. Comet-FISH results indicated a significant shift in distribution of signals for the TP 53 gene toward a more frequent occurrence in the comet tail. Prolonged exposure to possible carcinogens may hinder DNA repair mechanisms and affect structural integrity of TP 53 Two indicators of loss of TP 53 gene integrity have risen, namely, TP 53 fragmentation rate in lymphocytes with persistently elevated primary damage and incidence of TP 53 deletions in undamaged lymphocytes. © The Author(s) 2015.

Natural products used as a chemical library for protein-protein interaction targeted drug discovery.

PubMed

Jin, Xuemei; Lee, Kyungro; Kim, Nam Hee; Kim, Hyun Sil; Yook, Jong In; Choi, Jiwon; No, Kyoung Tai

2018-01-01

Protein-protein interactions (PPIs), which are essential for cellular processes, have been recognized as attractive therapeutic targets. Therefore, the construction of a PPI-focused chemical library is an inevitable necessity for future drug discovery. Natural products have been used as traditional medicines to treat human diseases for millennia; in addition, their molecular scaffolds have been used in diverse approved drugs and drug candidates. The recent discovery of the ability of natural products to inhibit PPIs led us to use natural products as a chemical library for PPI-targeted drug discovery. In this study, we collected natural products (NPDB) from non-commercial and in-house databases to analyze their similarities to small-molecule PPI inhibitors (iPPIs) and FDA-approved drugs by using eight molecular descriptors. Then, we evaluated the distribution of NPDB and iPPIs in the chemical space, represented by the molecular fingerprint and molecular scaffolds, to identify the promising scaffolds, which could interfere with PPIs. To investigate the ability of natural products to inhibit PPI targets, molecular docking was used. Then, we predicted a set of high-potency natural products by using the iPPI-likeness score based on a docking score-weighted model. These selected natural products showed high binding affinities to the PPI target, namely XIAP, which were validated in an in vitro experiment. In addition, the natural products with novel scaffolds might provide a promising starting point for further medicinal chemistry developments. Overall, our study shows the potency of natural products in targeting PPIs, which might help in the design of a PPI-focused chemical library for future drug discovery. Copyright © 2017 Elsevier Inc. All rights reserved.

Mechanisms of toxicity and biomarkers of flavoring and flavor enhancing chemicals in emerging tobacco and non-tobacco products.

PubMed

Kaur, Gurjot; Muthumalage, Thivanka; Rahman, Irfan

2018-05-15

Tobacco products containing flavorings, such as electronic nicotine delivery devices (ENDS) or e-cigarettes, cigars/cigarillos, waterpipes, and heat-not-burn devices (iQOS) are continuously evolving. In addition to increasing the exposure of teenagers and adults to nicotine containing flavoring products and flavoring enhancers, chances of nicotine addiction through chronic use and abuse also increase. These flavorings are believed to be safe for ingestion, but little information is available about their effects on the lungs. In this review, we have discussed the in vitro and in vivo data on toxicity of flavoring chemicals in lung cells. We have further discussed the common flavoring agents, such as diacetyl and menthol, currently available detection methods, and the toxicological mechanisms associated with oxidative stress, inflammation, mucociliary clearance, and DNA damage in cells, mice, and humans. Finally, we present potential biomarkers that could be utilized for future risk assessment. This review provides crucial parameters important for evaluation of risk associated with flavoring agents and flavoring enhancers used in tobacco products and ENDS. Future studies can be designed to address the potential toxicity of inhaled flavorings and their biomarkers in users as well as in chronic exposure studies. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of date seeds on oxidative damage and antioxidant status in vivo.

PubMed

Habib, Hosam M; Ibrahim, Wissam H

2011-07-01

Date seeds have been shown to contain high amounts of antioxidants. However, in vivo studies on date seeds are lacking. Therefore the purpose of this study was to determine the effect of date seeds on oxidative damage and antioxidant status in vivo. Male Wistar rats were fed a basal diet containing 0, 70 or 140 g kg(-1) date seeds for 30 days. All three diets were isonitrogenous and isocaloric. Indication of oxidative damage was assessed in the liver and serum, and antioxidant status was assessed in the liver. Serum biochemical parameters, including indicators of tissue cellular damage and complete blood count with differential, were also determined. The results showed that date seeds significantly (P<0.05) reduced liver and serum malondialdehyde (a lipid peroxidative damage product) and serum lactate dehydrogenase and creatine kinase. Liver antioxidants (vitamin E, vitamin C, glutathione, superoxide dismutase, glutathione peroxidase and catalase), complete blood count with differential and other serum biochemical parameters assessed were not significantly altered by date seeds. The results obtained suggest a protective effect of date seeds against in vivo oxidative damage, possibly through the action of their bioactive antioxidants. Copyright © 2011 Society of Chemical Industry.

Top value platform chemicals: bio-based production of organic acids.

PubMed

Becker, Judith; Lange, Anna; Fabarius, Jonathan; Wittmann, Christoph

2015-12-01

Driven by the quest for sustainability, recent years have seen a tremendous progress in bio-based production routes from renewable raw materials to commercial goods. Particularly, the production of organic acids has crystallized as a competitive and fast-evolving field, related to the broad applicability of organic acids for direct use, as polymer building blocks, and as commodity chemicals. Here, we review recent advances in metabolic engineering and industrial market scenarios with focus on organic acids as top value products from biomass, accessible through fermentation and biotransformation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Formic acid production using a microbial electrolysis desalination and chemical-production cell.

PubMed

Lu, Yaobin; Luo, Haiping; Yang, Kunpeng; Liu, Guangli; Zhang, Renduo; Li, Xiao; Ye, Bo

2017-11-01

The aim of this study was to investigate the feasibility and optimization of formic acid production in the microbial electrolysis desalination and chemical-production cell (MEDCC). The maximum current density in the MEDCC with 72cm of the anode fiber length (72-MEDCC) reached 24.0±2.0A/m 2 , which was much higher than previously reported. The maximum average formic acid production rate in the 72-MEDCC was 5.28 times higher than that in the MEDCC with 24cm of the anode fiber length (37.00±1.15vs. 7.00±0.25mg/h). High performance in the 72-MEDCC was attributed to small membrane spacing (1mm), high flow rate (1500μL/min) on the membrane surface and high anode biomass. The minimum electricity consumption of 0.34±0.04kWh/kg in the 72-MEDCC was only 3.1-18.8% of those in the EDBMs. The MEDCC should be a promising technology for the formic acid production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of heat damage in an autoclave on the reactive lysine contents of soy products and corn distillers dried grains with solubles. Use of the results to check on lysine damage in common qualities of these ingredients.

PubMed

Fontaine, Johannes; Zimmer, Ulrike; Moughan, Paul J; Rutherfurd, Shane M

2007-12-26

The suitability of the homoarginine reaction for determining the reactive lysine in soy products and corn distillers dried grain with solubles (DDGS) was tested. For this purpose, some batches were subjected to deliberate heat damage for up to 30 min in an autoclave with 135 degrees C hot steam, and the samples were analyzed for total lysine and reactive lysine. In addition, 84 samples of common soy and 80 samples of corn DDGS were tested for their content of total and reactive lysine, and the contents were compared with those of the autoclave tests. For soy products conclusive results were obtained. In the case of heat treatment, both total lysine and reactive lysine decrease, but the latter is clearly a more sensitive indicator of lysine damage. Most normal products are quite similar, with toasting-induced damage to reactive lysine of ca. 15% compared to untoasted beans. The cause of the constantly occurring residual lysine after guanidination and the poorer reaction balance in the case of damage were explained. For common DDGS samples, however, less favorable results were obtained. Reactive and total lysine decreased almost in parallel due to heat damage, showing a great gap between them. Results showed indeed that variation of total and reactive lysine in DDGS is high, proving that its production conditions are not yet optimal for a feed ingredient.

Impact of synthetic biology and metabolic engineering on industrial production of fine chemicals.

PubMed

Jullesson, David; David, Florian; Pfleger, Brian; Nielsen, Jens

2015-11-15

Industrial bio-processes for fine chemical production are increasingly relying on cell factories developed through metabolic engineering and synthetic biology. The use of high throughput techniques and automation for the design of cell factories, and especially platform strains, has played an important role in the transition from laboratory research to industrial production. Model organisms such as Saccharomyces cerevisiae and Escherichia coli remain widely used host strains for industrial production due to their robust and desirable traits. This review describes some of the bio-based fine chemicals that have reached the market, key metabolic engineering tools that have allowed this to happen and some of the companies that are currently utilizing these technologies for developing industrial production processes. Copyright © 2015 Elsevier Inc. All rights reserved.

Damage to Candida albicans Hyphae and Pseudohyphae by the Myeloperoxidase System and Oxidative Products of Neutrophil Metabolism In Vitro

PubMed Central

Diamond, Richard D.; Clark, Robert A.; Haudenschild, Christian C.

1980-01-01

In previous studies, we noted that Candida hyphae and pseudohyphae could be damaged and probably killed by neutrophils, primarily by oxygen-dependent nonphagocytic mechanisms. In extending these studies, amount of damage to hyphae again was measured by inhibition of [14C]cytosine uptake. Neutrophils from only one of four patients with chronic granulomatous disease damaged hyphae at all, and neutrophils from this single patient damaged hyphae far less efficiently than simultaneously tested neutrophils from normal control subjects. Neutrophils from neither of two subjects with hereditary myeloperoxidase deficiency damaged the hyphae. This confirmed the importance of oxidative mechanisms in general and myeloperoxidase-mediated systems in particular in damaging Candida hyphae. Several potentially fungicidal oxidative intermediates are produced by metabolic pathways of normal neutrophils, but their relative toxicity for Candida hyphae was previously unknown. To help determine this, cell-free in vitro systems were used to generate these potentially microbicidal products. Myeloperoxidase with hydrogen peroxide, iodide, and chloride resulted in 91.2% damage to hyphal inocula in 11 experiments. There was less damage when either chloride or iodide was omitted, and no damage when myeloperoxidase was omitted or inactivated by heating. Azide, cyanide, and catalase (but not heated catalase) inhibited the damage. Systems for generation of hydrogen peroxide could replace reagent hydrogen peroxide in the myeloperoxidase system. These included glucose oxidase, in the presence of glucose, and xanthine oxidase, in the presence of either hypoxanthine or acetaldehyde. In the presence of myeloperoxidase and a halide, the toxicity of the xanthine oxidase system was not inhibited by superoxide dismutase and, under some conditions, was marginally increased by this enzyme. This suggested that superoxide radical did not damage hyphae directly but served primarily as an intermediate in the

16 CFR 301.22 - Disclosure of damaged furs.

Code of Federal Regulations, 2011 CFR

2011-01-01

... decrease the normal life and durability of such product. (b) When damaged furs are used in a fur product..., or advertising such product; as for example: Mink Fur origin: Canada Contains Damaged Fur ...

High-energy electron-induced damage production at room temperature in aluminum-doped silicon

NASA Technical Reports Server (NTRS)

Corbett, J. W.; Cheng, L. J.; Jaworowski, A.; Karins, J. P.; Lee, Y. H.; Lindstroem, L.; Mooney, P. M.; Oehrlen, G.; Wang, K. L.

1979-01-01

DLTS and EPR measurements are reported on aluminum-doped silicon that was irradiated at room temperature with high-energy electrons. Comparisons are made to comparable experiments on boron-doped silicon. Many of the same defects observed in boron-doped silicon are also observed in aluminum-doped silicon, but several others were not observed, including the aluminum interstitial and aluminum-associated defects. Damage production modeling, including the dependence on aluminum concentration, is presented.

DNA damage and repair after high LET radiation

NASA Astrophysics Data System (ADS)

O'Neill, Peter; Cucinotta, Francis; Anderson, Jennifer

Predictions from biophysical models of interactions of radiation tracks with cellular DNA indicate that clustered DNA damage sites, defined as two or more lesions formed within one or two helical turns of the DNA by passage of a single radiation track, are formed in mammalian cells. These complex DNA damage sites are regarded as a signature of ionizing radiation exposure particularly as the likelihood of clustered damage sites arising endogenously is low. For instance, it was predicted from biophysical modelling that 30-40% of low LET-induced double strand breaks (DSB), a form of clustered damage, are complex with the yield increasing to >90% for high LET radiation, consistent with the reduced reparability of DSB with increasing ionization density of the radiation. The question arises whether the increased biological effects such as mutagenesis, carcinogenesis and lethality is in part related to DNA damage complexity and/or spatial distribution of the damage sites, which may lead to small DNA fragments. With particle radiation it is also important to consider not only delta-rays which may cause clustered damaged sites and may be highly mutagenic but the non-random spatial distribution of DSB which may lead to deletions. In this overview I will concentrate on the molecular aspects of the variation of the complexity of DNA damage on radiation quality and the challenges this complexity presents the DNA damage repair pathways. I will draw on data from micro-irradiations which indicate that the repair of DSBs by non-homologous end joining is highly regulated with pathway choice and kinetics of repair dependent on the chemical complexity of the DSB. In summary the aim is to emphasis the link between the spatial distribution of energy deposition events related to the track, the molecular products formed and the consequence of damage complexity contributing to biological effects and to present some of the outstanding molecular challenges with particle radiation.

[Serious product accidents due to the chemical substances used in household products in fiscal years 2007 and 2008].

PubMed

Isama, Kazuo

2009-01-01

The revised consumer product safety law was enforced in 2007. Then, the collection and publication system of the information of product accidents was newly included. Serious product accidents due to the chemical substances used in household products had 32 cases in fiscal years 2007 and 2008. These household products were a desk mat, a sectional bed, a spray-type adhesive, a paint and an adhesive for table tennis rackets. The safety measure of the household product was explained based on the law for the control of household products containing harmful substances.

Use of the Chemical Transformation Simulator as a Parameterization Tool for Modeling the Environmental Fate of Organic Chemicals and their Transformation Products

EPA Science Inventory

A Chemical Transformation Simulator is a web-based system for predicting transformation pathways and physicochemical properties of organic chemicals. Role in Environmental Modeling • Screening tool for identifying likely transformation products in the environment • Parameteri...

Application of Hydrophilic Silanol-Based Chemical Grout for Strengthening Damaged Reinforced Concrete Flexural Members

PubMed Central

Ju, Hyunjin; Lee, Deuck Hang; Cho, Hae-Chang; Kim, Kang Su; Yoon, Seyoon; Seo, Soo-Yeon

2014-01-01

In this study, hydrophilic chemical grout using silanol (HCGS) was adopted to overcome the performance limitations of epoxy materials used for strengthening existing buildings and civil engineering structures. The enhanced material performances of HCGS were introduced, and applied to the section enlargement method, which is one of the typical structural strengthening methods used in practice. To evaluate the excellent structural strengthening performance of the HCGS, structural tests were conducted on reinforced concrete beams, and analyses on the flexural behaviors of test specimens were performed by modified partial interaction theory (PIT). In particular, to improve the constructability of the section enlargement method, an advanced strengthening method was proposed, in which the precast panel was directly attached to the bottom of the damaged structural member by HCGS, and the degree of connection of the test specimens, strengthened by the section enlargement method, were quantitatively evaluated by PIT-based analysis. PMID:28788708

Application of Hydrophilic Silanol-Based Chemical Grout for Strengthening Damaged Reinforced Concrete Flexural Members.

PubMed

Ju, Hyunjin; Lee, Deuck Hang; Cho, Hae-Chang; Kim, Kang Su; Yoon, Seyoon; Seo, Soo-Yeon

2014-06-23

In this study, hydrophilic chemical grout using silanol (HCGS) was adopted to overcome the performance limitations of epoxy materials used for strengthening existing buildings and civil engineering structures. The enhanced material performances of HCGS were introduced, and applied to the section enlargement method, which is one of the typical structural strengthening methods used in practice. To evaluate the excellent structural strengthening performance of the HCGS, structural tests were conducted on reinforced concrete beams, and analyses on the flexural behaviors of test specimens were performed by modified partial interaction theory (PIT). In particular, to improve the constructability of the section enlargement method, an advanced strengthening method was proposed, in which the precast panel was directly attached to the bottom of the damaged structural member by HCGS, and the degree of connection of the test specimens, strengthened by the section enlargement method, were quantitatively evaluated by PIT-based analysis.

Roadmap for a Smart Factory: A Modular, Intelligent Concept for the Production of Specialty Chemicals.

PubMed

Reitze, Arnulf; Jürgensmeyer, Nikolas; Lier, Stefan; Kohnke, Marco; Riese, Julia; Grünewald, Marcus

2018-04-09

Digitalization and increasing the flexibility of production concepts offer the possibility to react to market challenges in the field of specialty chemicals. Shorter product lifetimes, increasing product individualization, and the resulting market volatility impose new requirements on plant operators. Novel concepts such as modular production plants and developments in digitalization (Industry 4.0) are able to assist the implementation of smart factories in specialty chemicals. These essential concepts will be presented in this Minireview. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

OrganoRelease - A framework for modeling the release of organic chemicals from the use and post-use of consumer products.

PubMed

Tao, Mengya; Li, Dingsheng; Song, Runsheng; Suh, Sangwon; Keller, Arturo A

2018-03-01

Chemicals in consumer products have become the focus of recent regulatory developments including California's Safer Consumer Products Act. However, quantifying the amount of chemicals released during the use and post-use phases of consumer products is challenging, limiting the ability to understand their impacts. Here we present a comprehensive framework, OrganoRelease, for estimating the release of organic chemicals from the use and post-use of consumer products given limited information. First, a novel Chemical Functional Use Classifier estimates functional uses based on chemical structure. Second, the quantity of chemicals entering different product streams is estimated based on market share data of the chemical functional uses. Third, chemical releases are estimated based on either chemical product categories or functional uses by using the Specific Environmental Release Categories and EU Technological Guidance Documents. OrganoRelease connects 19 unique functional uses and 14 product categories across 4 data sources and provides multiple pathways for chemical release estimation. Available user information can be incorporated in the framework at various stages. The Chemical Functional Use Classifier achieved an average accuracy above 84% for nine functional uses, which enables the OrganoRelease to provide release estimates for the chemical, mostly using only the molecular structure. The results can be can be used as input for methods estimating environmental fate and exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

Phenodynamics of production and chemical pools in mayapple and flowering dogwood

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, F.G. Jr.

1991-01-01

The objective of this study is to provide an understanding of the seasonality of biomass production and chemical storage among selected forest species as an aid to the analysis and management of a forest ecosystem model. The specific goals to accomplish the objectives included: (1) the construction of phenological calendars to be superimposed on the civil calendar, such that the seasons of the year are not marked by calendar dates but rather by dated groups of phenological events; (2) to develop a capability to predict onset of the generative phase (flowering) from heat unit summation methods; (3) to illustrate themore » role of phenology to biomass production and chemical storage in two indicator species, mayapple and flowering dogwood; and (4) to develop the capability to predict aboveground and below ground standing crop biomass in dogwood. Observations in this study focused on the generative phases (flowering) of individual plants and colonies of plants as indicators of productivity. 16 figs., 11 tabs.« less

Mechanism of Action of Lung Damage Caused by a Nanofilm Spray Product

PubMed Central

Larsen, Søren T.; Dallot, Constantin; Larsen, Susan W.; Rose, Fabrice; Poulsen, Steen S.; Nørgaard, Asger W.; Hansen, Jitka S.; Sørli, Jorid B.; Nielsen, Gunnar D.; Foged, Camilla

2014-01-01

Inhalation of waterproofing spray products has on several occasions caused lung damage, which in some cases was fatal. The present study aims to elucidate the mechanism of action of a nanofilm spray product, which has been shown to possess unusual toxic effects, including an extremely steep concentration-effect curve. The nanofilm product is intended for application on non-absorbing flooring materials and contains perfluorosiloxane as the active film-forming component. The toxicological effects and their underlying mechanisms of this product were studied using a mouse inhalation model, by in vitro techniques and by identification of the binding interaction. Inhalation of the aerosolized product gave rise to increased airway resistance in the mice, as evident from the decreased expiratory flow rate. The toxic effect of the waterproofing spray product included interaction with the pulmonary surfactants. More specifically, the active film-forming components in the spray product, perfluorinated siloxanes, inhibited the function of the lung surfactant due to non-covalent interaction with surfactant protein B, a component which is crucial for the stability and persistence of the lung surfactant film during respiration. The active film-forming component used in the present spray product is also found in several other products on the market. Hence, it may be expected that these products may have a toxicity similar to the waterproofing product studied here. Elucidation of the toxicological mechanism and identification of toxicological targets are important to perform rational and cost-effective toxicological studies. Thus, because the pulmonary surfactant system appears to be an important toxicological target for waterproofing spray products, study of surfactant inhibition could be included in toxicological assessment of this group of consumer products. PMID:24863969

PRISM 3: expanded prediction of natural product chemical structures from microbial genomes

PubMed Central

Skinnider, Michael A.; Merwin, Nishanth J.; Johnston, Chad W.

2017-01-01

Abstract Microbial natural products represent a rich resource of pharmaceutically and industrially important compounds. Genome sequencing has revealed that the majority of natural products remain undiscovered, and computational methods to connect biosynthetic gene clusters to their corresponding natural products therefore have the potential to revitalize natural product discovery. Previously, we described PRediction Informatics for Secondary Metabolomes (PRISM), a combinatorial approach to chemical structure prediction for genetically encoded nonribosomal peptides and type I and II polyketides. Here, we present a ground-up rewrite of the PRISM structure prediction algorithm to derive prediction of natural products arising from non-modular biosynthetic paradigms. Within this new version, PRISM 3, natural product scaffolds are modeled as chemical graphs, permitting structure prediction for aminocoumarins, antimetabolites, bisindoles and phosphonate natural products, and building upon the addition of ribosomally synthesized and post-translationally modified peptides. Further, with the addition of cluster detection for 11 new cluster types, PRISM 3 expands to detect 22 distinct natural product cluster types. Other major modifications to PRISM include improved sequence input and ORF detection, user-friendliness and output. Distribution of PRISM 3 over a 300-core server grid improves the speed and capacity of the web application. PRISM 3 is available at http://magarveylab.ca/prism/. PMID:28460067

Chemical precursor to optical damage detected by laser ionization mass spectrometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Estler, R.C.; Nogar, N.S.

1988-06-27

Mass spectrometry was used in conjunction with Nomarski microscopy to characterize the initiation of optical damage in selected commercial optics. The reflective optics (351 nm) consisted of Sc/sub 2/O/sub 3//SiO/sub 2/ multilayer coatings on 7940 (glass) substrates. These samples were exposed to loosely focused 1.06 ..mu..m, 10 ns pulses at 10 Hz. At fluences above 100 mJ/cm/sup 2/, transient iron signals were observed at each increasing fluence level, with concomitant appearance of small circular (10 ..mu..m) pits in the surface. The latter was observed by Nomarski microscopy. These small pits were also associated with macroscopic damage features resulting from thresholdmore » damage testing.« less

Larval western bean cutworm feeding damage encourages the development of Gibberella ear rot on field corn.

PubMed

Parker, Nicole S; Anderson, Nolan R; Richmond, Douglas S; Long, Elizabeth Y; Wise, Kiersten A; Krupke, Christian H

2017-03-01

A 2 year study was conducted to determine whether western bean cutworm (Striacosta albicosta Smith) (WBC) larval feeding damage increases severity of the fungal disease Gibberella ear rot [Fusarium graminearum (Schwein.) Petch] in field corn (Zea mays L.). The effect of a quinone-outside inhibiting fungicide, pyraclostrobin, on Gibberella ear rot severity and mycotoxin production, both with and without WBC pressure, was also evaluated. The impact of each variable was assessed individually and in combination to determine the effect of each upon ear disease severity. There was a positive correlation between the presence of WBC larvae in field corn and Gibberella ear rot severity under inoculated conditions in the 2 years of the experiment. An application of pyraclostrobin did not impact Gibberella ear rot development when applied at corn growth stage R1 (silks first emerging). Feeding damage from WBC larvae significantly increases the development of F. graminearum in field corn. We conclude that an effective integrated management strategy for Gibberella ear rot should target the insect pest first, in an effort to limit disease severity and subsequent mycotoxin production by F. graminearum in kernels. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Lanthipeptides: chemical synthesis versus in vivo biosynthesis as tools for pharmaceutical production.

PubMed

Ongey, Elvis Legala; Neubauer, Peter

2016-06-07

Lanthipeptides (also called lantibiotics for those with antibacterial activities) are ribosomally synthesized post-translationally modified peptides having thioether cross-linked amino acids, lanthionines, as a structural element. Lanthipeptides have conceivable potentials to be used as therapeutics, however, the lack of stable, high-yield, well-characterized processes for their sustainable production limit their availability for clinical studies and further pharmaceutical commercialization. Though many reviews have discussed the various techniques that are currently employed to produce lanthipeptides, a direct comparison between these methods to assess industrial applicability has not yet been described. In this review we provide a synoptic comparison of research efforts on total synthesis and in vivo biosynthesis aimed at fostering lanthipeptides production. We further examine current applications and propose measures to enhance product yields. Owing to their elaborate chemical structures, chemical synthesis of these biomolecules is economically less feasible for large-scale applications, and hence biological production seems to be the only realistic alternative.

Estimating chemical ecotoxicity in EU ecolabel and in EU product environmental footprint.

PubMed

Saouter, Erwan; De Schryver, An; Pant, Rana; Sala, Serenella

2018-05-21

The EU Commission Ecolabel and the Product and Environmental Footprint (PEF) aim at promoting the development and consumption of greener products. The product aquatic toxicity score from these 2 methods may lead in some circumstances to opposite conclusions. Although this could be interpreted as an inconsistency, the score should not be compared to each other but used in a complementary way. In short, CDV provided a "full" product formula aquatic toxicity score, even if some chemicals may never reach or persist in freshwater ecosystems. The USEtox® score, by integrating fate and exposure, focuses on the potential toxicity of persistent-water-soluble chemicals at steady state. Since no risk or safety assessment can be conducted with USEtox® nor with the CDV, both are a hazard-based scoring system. This short communication clarifies the difference between approaches underpinning the toxicity scores used in Ecolabel and PEF, providing guidance on how to interpret the results. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Reduced product yield in chemical processes by second law effects

NASA Technical Reports Server (NTRS)

England, C.; Funk, J. E.

1980-01-01

An analysis of second law effects in chemical processes, where product yield is explicitly related to the individual irreversibilities within the process to indicate a maximum theoretical yield, is presented. Examples are given that indicate differences between first and second law approaches toward process efficiency and process yield. This analysis also expresses production capacity in terms of the heating value of a product. As a result, it is particularly convenient in analyzing fuel conversion plants and their potential for improvement. Relationships are also given for the effects of irreversibilities on requirements for process heat and for feedstocks.

Comparative analysis of chemical similarity methods for modular natural products with a hypothetical structure enumeration algorithm.

PubMed

Skinnider, Michael A; Dejong, Chris A; Franczak, Brian C; McNicholas, Paul D; Magarvey, Nathan A

2017-08-16

Natural products represent a prominent source of pharmaceutically and industrially important agents. Calculating the chemical similarity of two molecules is a central task in cheminformatics, with applications at multiple stages of the drug discovery pipeline. Quantifying the similarity of natural products is a particularly important problem, as the biological activities of these molecules have been extensively optimized by natural selection. The large and structurally complex scaffolds of natural products distinguish their physical and chemical properties from those of synthetic compounds. However, no analysis of the performance of existing methods for molecular similarity calculation specific to natural products has been reported to date. Here, we present LEMONS, an algorithm for the enumeration of hypothetical modular natural product structures. We leverage this algorithm to conduct a comparative analysis of molecular similarity methods within the unique chemical space occupied by modular natural products using controlled synthetic data, and comprehensively investigate the impact of diverse biosynthetic parameters on similarity search. We additionally investigate a recently described algorithm for natural product retrobiosynthesis and alignment, and find that when rule-based retrobiosynthesis can be applied, this approach outperforms conventional two-dimensional fingerprints, suggesting it may represent a valuable approach for the targeted exploration of natural product chemical space and microbial genome mining. Our open-source algorithm is an extensible method of enumerating hypothetical natural product structures with diverse potential applications in bioinformatics.

Enzymatic Specific Production and Chemical Functionalization of Phenylpropanone Platform Monomers from Lignin

PubMed Central

Hasegawa, Ryoichi; Kurosawa, Kanako; Maeda, Allyn H.; Koizumi, Toshio; Nishimura, Hiroshi; Okada, Hitomi; Qu, Chen; Saito, Kaori; Watanabe, Takashi; Hatada, Yuji

2016-01-01

Abstract Enzymatic catalysis is an ecofriendly strategy for the production of high‐value low‐molecular‐weight aromatic compounds from lignin. Although well‐definable aromatic monomers have been obtained from synthetic lignin‐model dimers, enzymatic‐selective synthesis of platform monomers from natural lignin has not been accomplished. In this study, we successfully achieved highly specific synthesis of aromatic monomers with a phenylpropane structure directly from natural lignin using a cascade reaction of β‐O‐4‐cleaving bacterial enzymes in one pot. Guaiacylhydroxylpropanone (GHP) and the GHP/syringylhydroxylpropanone (SHP) mixture are exclusive monomers from lignin isolated from softwood (Cryptomeria japonica) and hardwood (Eucalyptus globulus). The intermediate products in the enzymatic reactions show the capacity to accommodate highly heterologous substrates at the substrate‐binding sites of the enzymes. To demonstrate the applicability of GHP as a platform chemical for bio‐based industries, we chemically generate value‐added GHP derivatives for bio‐based polymers. Together with these chemical conversions for the valorization of lignin‐derived phenylpropanone monomers, the specific and enzymatic production of the monomers directly from natural lignin is expected to provide a new stream in “white biotechnology” for sustainable biorefineries. PMID:27878983

Resistant starch: a functional food that prevents DNA damage and chemical carcinogenesis.

PubMed

Navarro, S D; Mauro, M O; Pesarini, J R; Ogo, F M; Oliveira, R J

2015-03-06

Resistant starch is formed from starch and its degradation products and is not digested or absorbed in the intestine; thus, it is characterized as a fiber. Because fiber intake is associated with the prevention of DNA damage and cancer, the potential antigenotoxic, antimutagenic, and anticarcinogenic capabilities of resistant starch from green banana flour were evaluated. Animals were treated with 1,2-dimethylhydrazine and their diet was supplemented with 10% green banana flour according to the following resistant starch protocols: pretreatment, simultaneous treatment, post-treatment, and pre + continuous treatment. The results demonstrated that resistant starch is not genotoxic, mutagenic, or carcinogenic. The results suggest that resistant starch acts through desmutagenesis and bio-antimutagenesis, as well as by reducing aberrant crypt foci, thereby improving disease prognosis. These findings imply that green banana flour has therapeutic properties that should be explored for human dietary applications.

The environmental injustice of beauty: framing chemical exposures from beauty products as a health disparities concern.

PubMed

Zota, Ami R; Shamasunder, Bhavna

2017-10-01

The obstetrics-gynecology community has issued a call to action to prevent toxic environmental chemical exposures and their threats to healthy human reproduction. Recent committee opinions recognize that vulnerable and underserved women may be impacted disproportionately by environmental chemical exposures and recommend that reproductive health professionals champion policies that secure environmental justice. Beauty product use is an understudied source of environmental chemical exposures. Beauty products can include reproductive and developmental toxicants such as phthalates and heavy metals; however, disclosure requirements are limited and inconsistent. Compared with white women, women of color have higher levels of beauty product-related environmental chemicals in their bodies, independent of socioeconomic status. Even small exposures to toxic chemicals during critical periods of development (such as pregnancy) can trigger adverse health consequences (such as impacts on fertility and pregnancy, neurodevelopment, and cancer). In this commentary, we seek to highlight the connections between environmental justice and beauty product-related chemical exposures. We describe racial/ethnic differences in beauty product use (such as skin lighteners, hair straighteners, and feminine hygiene products) and the potential chemical exposures and health risks that are associated with these products. We also discuss how targeted advertising can take advantage of mainstream beauty norms to influence the use of these products. Reproductive health professionals can use this information to advance environmental justice by being prepared to counsel patients who have questions about toxic environmental exposures from beauty care products and other sources. Researchers and healthcare providers can also promote health-protective policies such as improved ingredient testing and disclosure for the beauty product industry. Future clinical and public health research should consider beauty

Prediction of novel synthetic pathways for the production of desired chemicals.

PubMed

Cho, Ayoun; Yun, Hongseok; Park, Jin Hwan; Lee, Sang Yup; Park, Sunwon

2010-03-28

There have been several methods developed for the prediction of synthetic metabolic pathways leading to the production of desired chemicals. In these approaches, novel pathways were predicted based on chemical structure changes, enzymatic information, and/or reaction mechanisms, but the approaches generating a huge number of predicted results are difficult to be applied to real experiments. Also, some of these methods focus on specific pathways, and thus are limited to expansion to the whole metabolism. In the present study, we propose a system framework employing a retrosynthesis model with a prioritization scoring algorithm. This new strategy allows deducing the novel promising pathways for the synthesis of a desired chemical together with information on enzymes involved based on structural changes and reaction mechanisms present in the system database. The prioritization scoring algorithm employing Tanimoto coefficient and group contribution method allows examination of structurally qualified pathways to recognize which pathway is more appropriate. In addition, new concepts of binding site covalence, estimation of pathway distance and organism specificity were taken into account to identify the best synthetic pathway. Parameters of these factors can be evolutionarily optimized when a newly proven synthetic pathway is registered. As the proofs of concept, the novel synthetic pathways for the production of isobutanol, 3-hydroxypropionate, and butyryl-CoA were predicted. The prediction shows a high reliability, in which experimentally verified synthetic pathways were listed within the top 0.089% of the identified pathway candidates. It is expected that the system framework developed in this study would be useful for the in silico design of novel metabolic pathways to be employed for the efficient production of chemicals, fuels and materials.

Pretty Good or Pretty Bad? The Ovary and Chemicals in Personal Care Products.

PubMed

Craig, Zelieann R; Ziv-Gal, Ayelet

2018-04-01

Personal care products (PCP) contain a myriad of chemicals generally formulated to provide a safe and beneficial use. Nonetheless, an increasing amount of laboratory animal and human studies indicate that some chemicals in PCP are associated with decreased hormone production, diminished ovarian reserve, ovarian cancer, and early pregnancy loss. The ovary is key to female fertility by providing the eggs and sex steroid hormones for fertilization and maintenance of reproductive function, respectively. Thus, understanding how chemicals in PCP affect the ovary will shed some light on their potential effects on female fertility. In this review, we provide an overview of: (1) ovarian function as a determinant of fertility in females, (2) the status of knowledge regarding the effects of seven common chemicals in PCP on the ovary, and (3) significant gaps in the literature along with opportunities to eliminate some of the gaps. Findings from the limited existing data suggest that chemicals in PCP such as dibutyl phthalate can reach the ovary in humans and impact its function in animal models. Unfortunately, it is still difficult to assess how relevant findings of experimental studies are to women because of lack of human exposure data for most of these chemicals and the lack of studies that mimic real-life exposures. In contrast to chemicals such as bisphenol A and dioxin, the investigation of the effects of chemicals in PCP on reproductive function is still limited and warrants further investigation to fill existing data gaps.

Biodiesel biorefinery: opportunities and challenges for microbial production of fuels and chemicals from glycerol waste.

PubMed

Almeida, João R M; Fávaro, Léia C L; Quirino, Betania F

2012-07-18

The considerable increase in biodiesel production worldwide in the last 5 years resulted in a stoichiometric increased coproduction of crude glycerol. As an excess of crude glycerol has been produced, its value on market was reduced and it is becoming a "waste-stream" instead of a valuable "coproduct". The development of biorefineries, i.e. production of chemicals and power integrated with conversion processes of biomass into biofuels, has been singled out as a way to achieve economically viable production chains, valorize residues and coproducts, and reduce industrial waste disposal. In this sense, several alternatives aimed at the use of crude glycerol to produce fuels and chemicals by microbial fermentation have been evaluated. This review summarizes different strategies employed to produce biofuels and chemicals (1,3-propanediol, 2,3-butanediol, ethanol, n-butanol, organic acids, polyols and others) by microbial fermentation of glycerol. Initially, the industrial use of each chemical is briefly presented; then we systematically summarize and discuss the different strategies to produce each chemical, including selection and genetic engineering of producers, and optimization of process conditions to improve yield and productivity. Finally, the impact of the developments obtained until now are placed in perspective and opportunities and challenges for using crude glycerol to the development of biodiesel-based biorefineries are considered. In conclusion, the microbial fermentation of glycerol represents a remarkable alternative to add value to the biodiesel production chain helping the development of biorefineries, which will allow this biofuel to be more competitive.

Composition and production rate of pharmaceutical and chemical waste from Xanthi General Hospital in Greece.

PubMed

Voudrias, Evangelos; Goudakou, Lambrini; Kermenidou, Marianthi; Softa, Aikaterini

2012-07-01

The objective of this work was to determine the composition and production rates of pharmaceutical and chemical waste produced by Xanthi General Hospital in Greece (XGH). This information is important to design and cost management systems for pharmaceutical and chemical waste, for safety and health considerations and for assessing environmental impact. A total of 233 kg pharmaceutical and 110 kg chemical waste was collected, manually separated and weighed over a period of five working weeks. The total production of pharmaceutical waste comprised 3.9% w/w of the total hazardous medical waste produced by the hospital. Total pharmaceutical waste was classified in three categories, vial waste comprising 51.1%, syringe waste with 11.4% and intravenous therapy (IV) waste with 37.5% w/w of the total. Vial pharmaceutical waste only was further classified in six major categories: antibiotics, digestive system drugs, analgesics, hormones, circulatory system drugs and "other". Production data below are presented as average (standard deviation in parenthesis). The unit production rates for total pharmaceutical waste for the hospital were 12.4 (3.90) g/patient/d and 24.6 (7.48) g/bed/d. The respective unit production rates were: (1) for vial waste 6.4 (1.6) g/patient/d and 13 (2.6) g/bed/d, (2) for syringe waste 1.4 (0.4) g/patient/d and 2.8 (0.8) g/bed/d and (3) for IV waste 4.6 (3.0) g/patient/d and 9.2 (5.9) g/bed/d. Total chemical waste was classified in four categories, chemical reagents comprising 18.2%, solvents with 52.3%, dyes and tracers with 18.2% and solid waste with 11.4% w/w of the total. The total production of chemical waste comprised 1.8% w/w of the total hazardous medical waste produced by the hospital. Thus, the sum of pharmaceutical and chemical waste was 5.7% w/w of the total hazardous medical waste produced by the hospital. The unit production rates for total chemical waste for the hospital were 5.8 (2.2) g/patient/d and 1.1 (0.4) g/exam/d. The respective

Post-incident monitoring to evaluate environmental damage from shipping incidents: chemical and biological assessments.

PubMed

Radović, Jagoš R; Rial, Diego; Lyons, Brett P; Harman, Christopher; Viñas, Lucia; Beiras, Ricardo; Readman, James W; Thomas, Kevin V; Bayona, Josep M

2012-10-30

Oil and chemical spills in the marine environment are an issue of growing concern. Oil exploration and exploitation is moving from the continental shelf to deeper waters, and to northern latitudes where the risk of an oil spill is potentially greater and may affect pristine ecosystems. Moreover, a growing number of chemical products are transported by sea and maritime incidents of hazardous and noxious substances (HNS) are expected to increase. Consequently, it seems timely to review all of the experience gained from past spills to be able to cope with appropriate response and mitigation strategies to combat future incidents. Accordingly, this overview is focused on the dissemination of the most successful approaches to both detect and assess accidental releases using chemical as well as biological approaches for spills of either oil or HNS in the marine environment. Aerial surveillance, sampling techniques for water, suspended particles, sediments and biota are reviewed. Early warning bioassays and biomarkers to assess spills are also presented. Finally, research needs and gaps in knowledge are discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Chemical stability of insulin. 5. Isolation, characterization and identification of insulin transformation products.

PubMed

Brange, J; Hallund, O; Sørensen, E

1992-01-01

During storage of insulin formulated for therapy, minor amounts of various degradation and covalent di- and polymerization products are formed [1-3]. The main chemical transformation products were isolated from aged preparations and characterized chemically and biologically. The most prominent products formed in neutral medium were identified as a mixture of deamidation products hydrolyzed at residue B3, namely isoAsp B3 and Asp B3 derivatives. A hydrolysis product formed only in crystals of insulin zinc suspensions containing a surplus of zinc ions in the supernatant was identified as an A8-A9 cleavage product. The small amounts of covalent insulin dimers (CID) formed in all formulations were shown to be a heterogenous mixture of 5-6 different CIDs with a composition dependent on the pharmaceutical formulation. The chemical characteristics of the CIDs indicate that they are formed through a transamidation reaction mainly between the B-chain N-terminal and one of the four amide side-chains of the A chain. GlnA15, AsnA18 and, in particular, AsnA21 participate in the formation of such isopeptide links between two insulin molecules. The covalent insulin-protamine products (CIPP) formed during storage of NPH preparations presumably originate from a similar reaction between the protamine N-terminal with an amide in insulin. Covalent polymerization products, mainly formed during storage of amorphously suspended insulin at higher temperature, were shown to be due to disulfide interactions. Biological in vivo potencies relative to native insulin were less than 2% for the split-(A8-A9)-product and for the covalent disulfide exchange polymers, 4% for the CIPP, approximately 15% for the CIDs, whereas the B3 derivatives exhibited full potency. Rabbit immunization experiments revealed that none of the insulin transformation products had significantly increased immunogenicity in rabbits.

Effects of Neurological Damage on Production of Formulaic Language

ERIC Educational Resources Information Center

Sidtis, Diana; Canterucci, Gina; Katsnelson, Dora

2009-01-01

Early studies reported preserved formulaic language in left hemisphere damaged subjects and reduced incidence of formulaic expressions in the conversational speech of stroke patients with right hemispheric damage. Clinical observations suggest a possible role also of subcortical nuclei. This study examined formulaic language in the spontaneous…

A novel biochemical route for fuels and chemicals production from cellulosic biomass.

PubMed

Fan, Zhiliang; Wu, Weihua; Hildebrand, Amanda; Kasuga, Takao; Zhang, Ruifu; Xiong, Xiaochao

2012-01-01

The conventional biochemical platform featuring enzymatic hydrolysis involves five key steps: pretreatment, cellulase production, enzymatic hydrolysis, fermentation, and product recovery. Sugars are produced as reactive intermediates for subsequent fermentation to fuels and chemicals. Herein, an alternative biochemical route is proposed. Pretreatment, enzymatic hydrolysis and cellulase production is consolidated into one single step, referred to as consolidated aerobic processing, and sugar aldonates are produced as the reactive intermediates for biofuels production by fermentation. In this study, we demonstrate the viability of consolidation of the enzymatic hydrolysis and cellulase production steps in the new route using Neurospora crassa as the model microorganism and the conversion of cellulose to ethanol as the model system. We intended to prove the two hypotheses: 1) cellulose can be directed to produce cellobionate by reducing β-glucosidase production and by enhancing cellobiose dehydrogenase production; and 2) both of the two hydrolysis products of cellobionate--glucose and gluconate--can be used as carbon sources for ethanol and other chemical production. Our results showed that knocking out multiple copies of β-glucosidase genes led to cellobionate production from cellulose, without jeopardizing the cellulose hydrolysis rate. Simulating cellobiose dehydrogenase over-expression by addition of exogenous cellobiose dehydrogenase led to more cellobionate production. Both of the two hydrolysis products of cellobionate: glucose and gluconate can be used by Escherichia coli KO 11 for efficient ethanol production. They were utilized simultaneously in glucose and gluconate co-fermentation. Gluconate was used even faster than glucose. The results support the viability of the two hypotheses that lay the foundation for the proposed new route.

A Novel Biochemical Route for Fuels and Chemicals Production from Cellulosic Biomass

PubMed Central

Fan, Zhiliang; Wu, Weihua; Hildebrand, Amanda; Kasuga, Takao; Zhang, Ruifu; Xiong, Xiaochao

2012-01-01

The conventional biochemical platform featuring enzymatic hydrolysis involves five key steps: pretreatment, cellulase production, enzymatic hydrolysis, fermentation, and product recovery. Sugars are produced as reactive intermediates for subsequent fermentation to fuels and chemicals. Herein, an alternative biochemical route is proposed. Pretreatment, enzymatic hydrolysis and cellulase production is consolidated into one single step, referred to as consolidated aerobic processing, and sugar aldonates are produced as the reactive intermediates for biofuels production by fermentation. In this study, we demonstrate the viability of consolidation of the enzymatic hydrolysis and cellulase production steps in the new route using Neurospora crassa as the model microorganism and the conversion of cellulose to ethanol as the model system. We intended to prove the two hypotheses: 1) cellulose can be directed to produce cellobionate by reducing β-glucosidase production and by enhancing cellobiose dehydrogenase production; and 2) both of the two hydrolysis products of cellobionate—glucose and gluconate—can be used as carbon sources for ethanol and other chemical production. Our results showed that knocking out multiple copies of β-glucosidase genes led to cellobionate production from cellulose, without jeopardizing the cellulose hydrolysis rate. Simulating cellobiose dehydrogenase over-expression by addition of exogenous cellobiose dehydrogenase led to more cellobionate production. Both of the two hydrolysis products of cellobionate: glucose and gluconate can be used by Escherichia coli KO 11 for efficient ethanol production. They were utilized simultaneously in glucose and gluconate co-fermentation. Gluconate was used even faster than glucose. The results support the viability of the two hypotheses that lay the foundation for the proposed new route. PMID:22384058

Physical and chemical microstructural damage in pressed CL-20 explosives

NASA Astrophysics Data System (ADS)

Demol, Gauthier; Sandusky, Harold W.

2000-04-01

The ultimate utility of CL-20 as an ingredient in explosive and propellant formulations will depend upon the ability to understand the factors that are responsible for batch-to-batch variability with respect to sensitivity, and also to control the sensitivity in formulations within acceptable limits. We used light microscopy of cold-mounted, polished samples to characterize CL-20 at various stages in its life cycle. The evolution of damage from the initial neat crystals of CL-20 to the ready-to-use pressed pellets shows that processing seriously damages the crystals. These crystals are very brittle, and several explanations are proposed.

15 CFR 714.3 - Advance declaration requirements for additionally planned production of Schedule 3 chemicals.

Code of Federal Regulations, 2010 CFR

2010-01-01

... additionally planned production of Schedule 3 chemicals. 714.3 Section 714.3 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 3 CHEMICALS § 714.3 Advance...

Prediction of Hydrolysis Products of Organic Chemicals under Environmental pH Conditions.

PubMed

Tebes-Stevens, Caroline; Patel, Jay M; Jones, W Jack; Weber, Eric J

2017-05-02

Cheminformatics-based software tools can predict the molecular structure of transformation products using a library of transformation reaction schemes. This paper presents the development of such a library for abiotic hydrolysis of organic chemicals under environmentally relevant conditions. The hydrolysis reaction schemes in the library encode the process science gathered from peer-reviewed literature and regulatory reports. Each scheme has been ranked on a scale of one to six based on the median half-life in a data set compiled from literature-reported hydrolysis rates. These ranks are used to predict the most likely transformation route when more than one structural fragment susceptible to hydrolysis is present in a molecule of interest. Separate rank assignments are established for pH 5, 7, and 9 to represent standard conditions in hydrolysis studies required for registration of pesticides in Organisation for Economic Co-operation and Development (OECD) member countries. The library is applied to predict the likely hydrolytic transformation products for two lists of chemicals, one representative of chemicals used in commerce and the other specific to pesticides, to evaluate which hydrolysis reaction pathways are most likely to be relevant for organic chemicals found in the natural environment.

31P NMR Chemical Shifts of Solvents and Products Impurities in Biomass Pretreatments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Mi; Yoo, Chang Geun; Pu, Yunqiao

The identification of chemical impurities is crucial in elucidating the structures of biorefinery products using nuclear magnetic resonance (NMR) spectroscopic analysis. In the current biorefinery platform, contaminants derived from pretreatment solvents and decomposition byproducts may lead to misassignment of the NMR spectra of biorefinery products (e.g, lignin and bio-oils). Therefore, we investigated in this paper 54 commonly reported compounds including alcohols, carbohydrates, organic acids, aromatics, aldehydes, and ionic liquids associated with biomass pretreatment using 31P NMR. The chemical shifts of these chemicals after derivatizing with 2-chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphospholane (TMDP) were provided. Finally, the 31P NMR signals of these derivatives could serve asmore » valuable and informative spectral data in characterizing lignocellulose-based compounds.« less

31P NMR Chemical Shifts of Solvents and Products Impurities in Biomass Pretreatments

DOE PAGES

Li, Mi; Yoo, Chang Geun; Pu, Yunqiao; ...

2017-12-05

The identification of chemical impurities is crucial in elucidating the structures of biorefinery products using nuclear magnetic resonance (NMR) spectroscopic analysis. In the current biorefinery platform, contaminants derived from pretreatment solvents and decomposition byproducts may lead to misassignment of the NMR spectra of biorefinery products (e.g, lignin and bio-oils). Therefore, we investigated in this paper 54 commonly reported compounds including alcohols, carbohydrates, organic acids, aromatics, aldehydes, and ionic liquids associated with biomass pretreatment using 31P NMR. The chemical shifts of these chemicals after derivatizing with 2-chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphospholane (TMDP) were provided. Finally, the 31P NMR signals of these derivatives could serve asmore » valuable and informative spectral data in characterizing lignocellulose-based compounds.« less

Clean Air Act Standards and Guidelines for Chemical Production and Distribution

EPA Pesticide Factsheets

This page contains the stationary sources of air pollution for the chemical production & distribution industries, and their corresponding air pollution regulations. To learn more about the regulations for each industry, click on the links below.

PRISM 3: expanded prediction of natural product chemical structures from microbial genomes.

PubMed

Skinnider, Michael A; Merwin, Nishanth J; Johnston, Chad W; Magarvey, Nathan A

2017-07-03

Microbial natural products represent a rich resource of pharmaceutically and industrially important compounds. Genome sequencing has revealed that the majority of natural products remain undiscovered, and computational methods to connect biosynthetic gene clusters to their corresponding natural products therefore have the potential to revitalize natural product discovery. Previously, we described PRediction Informatics for Secondary Metabolomes (PRISM), a combinatorial approach to chemical structure prediction for genetically encoded nonribosomal peptides and type I and II polyketides. Here, we present a ground-up rewrite of the PRISM structure prediction algorithm to derive prediction of natural products arising from non-modular biosynthetic paradigms. Within this new version, PRISM 3, natural product scaffolds are modeled as chemical graphs, permitting structure prediction for aminocoumarins, antimetabolites, bisindoles and phosphonate natural products, and building upon the addition of ribosomally synthesized and post-translationally modified peptides. Further, with the addition of cluster detection for 11 new cluster types, PRISM 3 expands to detect 22 distinct natural product cluster types. Other major modifications to PRISM include improved sequence input and ORF detection, user-friendliness and output. Distribution of PRISM 3 over a 300-core server grid improves the speed and capacity of the web application. PRISM 3 is available at http://magarveylab.ca/prism/. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Use of enzymes to minimize the rheological dough problems caused by high levels of damaged starch in starch-gluten systems.

PubMed

Barrera, Gabriela N; León, Alberto E; Ribotta, Pablo D

2016-05-01

During wheat milling, starch granules can experience mechanical damage, producing damaged starch. High levels of damaged starch modify the physicochemical properties of wheat flour, negatively affecting the dough behavior as well as the flour quality and cookie and bread making quality. The aim of this work was to evaluate the effect of α-amylase, maltogenic amylase and amyloglucosidase on dough rheology in order to propose alternatives to reduce the issues related to high levels of damaged starch. The dough with a high level of damaged starch became more viscous and resistant to deformations as well as less elastic and extensible. The soluble fraction of the doughs influenced the rheological behavior of the systems. The α-amylase and amyloglucosidase reduced the negative effects of high damaged starch contents, improving the dough rheological properties modified by damaged starch. The rheological behavior of dough with the higher damaged-starch content was related to a more open gluten network arrangement as a result of the large size of the swollen damaged starch granules. We can conclude that the dough rheological properties of systems with high damaged starch content changed positively as a result of enzyme action, particularly α-amylase and amyloglucosidase additions, allowing the use of these amylases and mixtures of them as corrective additives. Little information was reported about amyloglucosidase activity alone or combined with α-amylase. The combinations of these two enzymes are promising to minimize the negative effects caused by high levels of damaged starch on product quality. More research needs to be done on bread quality combining these two enzymes. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Advanced FTIR technology for the chemical characterization of product wafers

NASA Astrophysics Data System (ADS)

Rosenthal, P. A.; Bosch-Charpenay, S.; Xu, J.; Yakovlev, V.; Solomon, P. R.

2001-01-01

Advances in chemically sensitive diagnostic techniques are needed for the characterization of compositionally variable materials such as chemically amplified resists, low-k dielectrics and BPSG films on product wafers. In this context, Fourier Transform Infrared (FTIR) reflectance spectroscopy is emerging as a preferred technique to characterize film chemistry and composition, due to its non-destructive nature and excellent sensitivity to molecular bonds and free carriers. While FTIR has been widely used in R&D environments, its application to mainstream production metrology and process monitoring on product wafers has historically been limited. These limitations have been eliminated in a series of recent FTIR technology advances, which include the use of 1) new sampling optics, which suppress artifact backside reflections and 2) comprehensive model-based analysis. With these recent improvements, it is now possible to characterize films on standard single-side polished product wafers with much simpler training wafer sets and machine-independent calibrations. In this new approach, the chemistry of the films is tracked via the measured infrared optical constants as opposed to conventional absorbance measurements. The extracted spectral optical constants can then be reduced to a limited set of parameters for process control. This paper describes the application of this new FTIR methodology to the characterization of 1) DUV photoresists after various processing steps, 2) low-k materials of different types and after various curing conditions, and 3) doped glass BPSG films of various concentration and, for the first time, widely different thicknesses. Such measurements can be used for improved process control on actual product wafers.

Advances in metabolic pathway and strain engineering paving the way for sustainable production of chemical building blocks.

PubMed

Chen, Yun; Nielsen, Jens

2013-12-01

Bio-based production of chemical building blocks from renewable resources is an attractive alternative to petroleum-based platform chemicals. Metabolic pathway and strain engineering is the key element in constructing robust microbial chemical factories within the constraints of cost effective production. Here we discuss how the development of computational algorithms, novel modules and methods, omics-based techniques combined with modeling refinement are enabling reduction in development time and thus advance the field of industrial biotechnology. We further discuss how recent technological developments contribute to the development of novel cell factories for the production of the building block chemicals: adipic acid, succinic acid and 3-hydroxypropionic acid. Copyright © 2013 Elsevier Ltd. All rights reserved.

Exploring Chemical Routes Relevant to the Toxicity of Paracetamol and Its meta-Analogue at a Molecular Level.

PubMed

Castañeda-Arriaga, Romina; Galano, Annia

2017-06-19

Several chemical routes related to the toxicity of paracetamol (APAP, also known as acetaminophen), its analogue N-acetyl-m-aminophenol (AMAP), and their deacetylated derivatives, were investigated using the density functional theory. It was found that AMAP is more resilient to chemical oxidation than APAP. The chemical degradation of AMAP into radical intermediates is predicted to be significant only when it is induced by strong oxidants. This might explain the apparent contradictions among experimental evidence regarding AMAP toxicity. All of the investigated species are incapable of oxidizing DNA, but they can damage lipids by H atom transfer (HAT) from the bis-allylic site, with the phenoxyl radical of AMAP being the most threatening to the lipids' chemical integrity. Regarding protein damage, Cys residues were identified as the most likely targets. The damage in this case may involve two different routes: (i) HAT from the thiol site by phenoxyl radicals and (ii) protein arylation by the quinone imine (QI) derivatives. Both are not only thermochemically viable, but also are very fast reactions. According to the mechanism identified here as the most likely one for protein arylation, a rather large concentration of QI would be necessary for this damage to be significant. This might explain why APAP is nontoxic in therapeutic doses, while overdoses can result in hepatic toxicity. In addition, the QI derived from both APAP and AMAP were found to be capable of inflicting this kind of damage. In addition, it is proposed that they might increase • OH production via the Fenton reaction, which would contribute to their toxicity.

Biodiesel biorefinery: opportunities and challenges for microbial production of fuels and chemicals from glycerol waste

PubMed Central

2012-01-01

The considerable increase in biodiesel production worldwide in the last 5 years resulted in a stoichiometric increased coproduction of crude glycerol. As an excess of crude glycerol has been produced, its value on market was reduced and it is becoming a “waste-stream” instead of a valuable “coproduct”. The development of biorefineries, i.e. production of chemicals and power integrated with conversion processes of biomass into biofuels, has been singled out as a way to achieve economically viable production chains, valorize residues and coproducts, and reduce industrial waste disposal. In this sense, several alternatives aimed at the use of crude glycerol to produce fuels and chemicals by microbial fermentation have been evaluated. This review summarizes different strategies employed to produce biofuels and chemicals (1,3-propanediol, 2,3-butanediol, ethanol, n-butanol, organic acids, polyols and others) by microbial fermentation of glycerol. Initially, the industrial use of each chemical is briefly presented; then we systematically summarize and discuss the different strategies to produce each chemical, including selection and genetic engineering of producers, and optimization of process conditions to improve yield and productivity. Finally, the impact of the developments obtained until now are placed in perspective and opportunities and challenges for using crude glycerol to the development of biodiesel-based biorefineries are considered. In conclusion, the microbial fermentation of glycerol represents a remarkable alternative to add value to the biodiesel production chain helping the development of biorefineries, which will allow this biofuel to be more competitive. PMID:22809320

Pyrolysis of triglyceride materials for the production of renewable fuels and chemicals.

PubMed

Maher, K D; Bressler, D C

2007-09-01

Conversion of vegetable oils and animal fats composed predominantly of triglycerides using pyrolysis type reactions represents a promising option for the production of renewable fuels and chemicals. The purpose of this article was to collect and review literature on the thermo-chemical conversion of triglyceride based materials. The literature was divided and discussed as (1) direct thermal cracking and (2) combination of thermal and catalytic cracking. Typically, four main catalyst types are used including transition metal catalysts, molecular sieve type catalysts, activated alumina, and sodium carbonate. Reaction products are heavily dependant on the catalyst type and reaction conditions and can range from diesel like fractions to gasoline like fractions. Research in this area is not as advanced as bio-oil and bio-diesel research and there is opportunity for further study in the areas of reaction optimization, detailed characterization of products and properties, and scale-up.

[Chemical Constituents from Processed Products of Aconitum Vilmoriniani Radix].

PubMed

Guo, Zhi-jun; Yang, Zhu-ya; Tan, Wen-hong; Zhou, Zhi-hong; Ma, Xiao-xia

2015-05-01

To investigate the chemical constituents of the processed products of Aconitum Vilmorinian Radix. The constituents were isolated by repeated column chromatography over silica gel, alumina and RP-C18 as well as recrystallization. The structures were elucidated on the basis of spectral analysis and physicochemical properties. Ten compounds were obtained from the methanol extract, and they were identified as yunaconitine (1), 8-deacetyl-yunaconitine (2), geniculatine C (3), vilmorrianine B (4), vilmorrianine C(5), vilmorrianine D (6), talatisamine (7), β-sitosterol (8), β-daucosterol (9) and β-sitosterol acetate (10). All compounds are obtained from the processed products of Aconitum Vilmoriniani Radix for the first time.

SYNBIOCHEM-a SynBio foundry for the biosynthesis and sustainable production of fine and speciality chemicals.

PubMed

Carbonell, Pablo; Currin, Andrew; Dunstan, Mark; Fellows, Donal; Jervis, Adrian; Rattray, Nicholas J W; Robinson, Christopher J; Swainston, Neil; Vinaixa, Maria; Williams, Alan; Yan, Cunyu; Barran, Perdita; Breitling, Rainer; Chen, George Guo-Qiang; Faulon, Jean-Loup; Goble, Carole; Goodacre, Royston; Kell, Douglas B; Feuvre, Rosalind Le; Micklefield, Jason; Scrutton, Nigel S; Shapira, Philip; Takano, Eriko; Turner, Nicholas J

2016-06-15

The Manchester Synthetic Biology Research Centre (SYNBIOCHEM) is a foundry for the biosynthesis and sustainable production of fine and speciality chemicals. The Centre's integrated technology platforms provide a unique capability to facilitate predictable engineering of microbial bio-factories for chemicals production. An overview of these capabilities is described. © 2016 The Author(s).

Chemical investigation of commercial grape seed derived products to assess quality and detect adulteration.

PubMed

Villani, Tom S; Reichert, William; Ferruzzi, Mario G; Pasinetti, Giulio M; Simon, James E; Wu, Qingli

2015-03-01

Fundamental concerns in quality control arise due to increasing use of grape seed extract (GSE) and the complex chemical composition of GSE. Proanthocyanidin monomers and oligomers are the major bioactive compounds in GSE. Given no standardized criteria for quality, large variation exists in the composition of commercial GSE supplements. Using HPLC/UV/MS, 21 commercial GSE containing products were purchased and chemically profiled, major compounds quantitated, and compared against authenticated grape seed extract, peanut skin extract, and pine bark extract. The antioxidant capacity and total polyphenol content for each sample was also determined and compared using standard techniques. Nine products were adulterated, found to contain peanut skin extract. A wide degree of variability in chemical composition was detected in commercial products, demonstrating the need for development of quality control standards for GSE. A TLC method was developed to allow for rapid and inexpensive detection of adulteration in GSE by peanut skin. Copyright © 2014 Elsevier Ltd. All rights reserved.

Chemical Emissions of Residential Materials and Products: Review of Available Information

DOE Office of Scientific and Technical Information (OSTI.GOV)

Willem, Henry; Singer, Brett

2010-09-15

This report is prepared in the context of a larger program whose mission is to advance understanding of ventilation and indoor air quality in U.S. homes. A specific objective of this program is to develop the scientific basis ? through controlled experiments, monitoring and analysis ? for health risk-based ventilation standards. Appropriate and adequate ventilation is a basic element of a healthy home. Ventilation provides outdoor air and in the process removes indoor odors and contaminants including potentially unhealthful chemicals emitted by indoor materials, products and activities. Ventilation traditionally was assured to occur via infiltration of outdoor air through cracksmore » and other leakage pathways in the residential building envelope. As building air tightness is improved for energy efficiency, infiltration can be reduced to inadequate levels. This has lead to the development of standards requiring mechanical ventilation. Though nominally intended to ensure acceptable indoor air quality, the standards are not explicitly tied to health risk or pollutant exposure targets. LBNL is currently designing analyses to assess the impact of varying ventilation standards on pollutant concentrations, health risks and energy use. These analyses require information on sources of chemical pollutant emissions, ideally including emission rates and the impact of ventilation on emissions. Some information can be obtained from recent studies that report measurements of various air contaminants and their concentrations in U.S. residences. Another way to obtain this information is the bottom-up approach of collecting and evaluating emissions data from construction and interior materials and common household products. This review contributes to the latter approach by summarizing available information on chemical emissions from new residential products and materials. We review information from the scientific literature and public sources to identify and discuss the

Improving Flood Damage Assessment Models in Italy

NASA Astrophysics Data System (ADS)

Amadio, M.; Mysiak, J.; Carrera, L.; Koks, E.

2015-12-01

The use of Stage-Damage Curve (SDC) models is prevalent in ex-ante assessments of flood risk. To assess the potential damage of a flood event, SDCs describe a relation between water depth and the associated potential economic damage over land use. This relation is normally developed and calibrated through site-specific analysis based on ex-post damage observations. In some cases (e.g. Italy) SDCs are transferred from other countries, undermining the accuracy and reliability of simulation results. Against this background, we developed a refined SDC model for Northern Italy, underpinned by damage compensation records from a recent flood event. Our analysis considers both damage to physical assets and production losses from business interruptions. While the first is calculated based on land use information, production losses are measured through the spatial distribution of Gross Value Added (GVA). An additional component of the model assesses crop-specific agricultural losses as a function of flood seasonality. Our results show an overestimation of asset damage from non-calibrated SDC values up to a factor of 4.5 for tested land use categories. Furthermore, we estimate that production losses amount to around 6 per cent of the annual GVA. Also, maximum yield losses are less than a half of the amount predicted by the standard SDC methods.

Chemical Composition, Antioxidant, DNA Damage Protective, Cytotoxic and Antibacterial Activities of Cyperus rotundus Rhizomes Essential Oil against Foodborne Pathogens

PubMed Central

Hu, Qing-Ping; Cao, Xin-Ming; Hao, Dong-Lin; Zhang, Liang-Liang

2017-01-01

Cyperus rotundus L. (Cyperaceae) is a medicinal herb traditionally used to treat various clinical conditions at home. In this study, chemical composition of Cyperus rotundus rhizomes essential oil, and in vitro antioxidant, DNA damage protective and cytotoxic activities as well as antibacterial activity against foodborne pathogens were investigated. Results showed that α-cyperone (38.46%), cyperene (12.84%) and α-selinene (11.66%) were the major components of the essential oil. The essential oil had an excellent antioxidant activity, the protective effect against DNA damage, and cytotoxic effects on the human neuroblastoma SH-SY5Y cell, as well as antibacterial activity against several foodborne pathogens. These biological activities were dose-dependent, increasing with higher dosage in a certain concentration range. The antibacterial effects of essential oil were greater against Gram-positive bacteria as compared to Gram-negative bacteria, and the antibacterial effects were significantly influenced by incubation time and concentration. These results may provide biological evidence for the practical application of the C. rotundus rhizomes essential oil in food and pharmaceutical industries. PMID:28338066

Production and physico-chemical characterisation of nanoparticles.

PubMed

Schulze Isfort, C; Rochnia, M

2009-05-08

Synthetic nanoscaled metal oxides are mainly produced by pyrogenic decomposition of precursors in the gas phase using a hot-wall or plasma reactor. Due to their low production rate and limited scalability, these processes are of minor technical relevance in manufacturing commercial quantities of nanoparticles. The most common and by far the most important industrial process is flame hydrolysis. In this process, a gaseous mixture of a metal chloride precursor, hydrogen and air is introduced in a closed and continuously operated flame reactor. The general mechanism of formation and growth of particles (e.g. silica) occurring in the flame is dominated by nucleation, coalescence (sintering) and coagulation (collision) of primary particles forming aggregated structures. The term 'aggregate' describes clusters of particles held together by strong chemical bonds. Agglomerates, however, are defined as loose accumulations of particles held together by hydrogen bonds for example. Although, a variety of physico-chemical methods exist to characterise pyrogenic oxides, the most important ones are analysis of the specific surface area by the so-called BET method, determination of the aggregate size by transmission electron microscopy (TEM) and characterisation of the phase composition by means of X-ray analysis.

Chemical ecology of antibiotic production by actinomycetes.

PubMed

van der Meij, Anne; Worsley, Sarah F; Hutchings, Matthew I; van Wezel, Gilles P

2017-05-01

Actinomycetes are a diverse family of filamentous bacteria that produce a plethora of natural products relevant for agriculture, biotechnology and medicine, including the majority of the antibiotics we use in the clinic. Rather than as free-living bacteria, many actinomycetes have evolved to live in symbiosis with among others plants, fungi, insects and sponges. As a common theme, these organisms profit from the natural products and enzymes produced by the actinomycetes, for example, for protection against pathogenic microbes, for growth promotion or for the degradation of complex natural polymers such as lignocellulose. At the same time, the actinomycetes benefit from the resources of the hosts they interact with. Evidence is accumulating that these interactions control the expression of biosynthetic gene clusters and have played a major role in the evolution of the high chemical diversity of actinomycete-produced secondary metabolites. Many of the biosynthetic gene clusters for antibiotics are poorly expressed under laboratory conditions, but they are likely expressed in response to host-specific demands. Here, we review the environmental triggers and cues that control natural product formation by actinomycetes and provide pointers as to how these insights may be harnessed for drug discovery. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

FUGITIVE EMISSION SOURCES AND BATCH OPERATIONS IN SYNTHETIC ORGANIC CHEMICAL PRODUCTION

EPA Science Inventory

This survey report was developed for the EPA for use in assessing the potential magnitude of fugitive volatile organic compound (VOC) emissions from agitator seals, cooling towers and batch operations in the production of 378 designated chemicals. The information presented in thi...

Analysis of Ricefield Land Damage in Denpasar City, Bali, Indonesia

NASA Astrophysics Data System (ADS)

Suyarto, R.; Wiyanti; Dibia, I. N.

2018-02-01

Soil as a natural resource, living area, environmental media, and factors of production including biomass production that supports human life and other living beings must be preserved, on the other hand, uncontrolled biomass production activities can cause soil damage, ultimately can threaten the survival of humans and other living things. Therefore, in order to control soil damage, first must inventories the soil condition data and its damage which then visualised in soil damage potential and soil damage status. The activities of the study are the preparation of a map of the initial soil conditions and the delineation of potentially land degradation distribution. Mapping results are used as work maps for verification on the field to take soil samples and create soil damage status. In general, Denpasar City have soil damage potential at very low, low until medium rate. Soil damage status in Denpasar City generally is low damage of bulk volume, total porosity, soil permeability and electrolyte conductivity which beyond limitation thresholds.

Consumer Product Chemicals in Indoor Dust: A Quantitative Meta-analysis of U.S. Studies

PubMed Central

2016-01-01

Indoor dust is a reservoir for commercial consumer product chemicals, including many compounds with known or suspected health effects. However, most dust exposure studies measure few chemicals in small samples. We systematically searched the U.S. indoor dust literature on phthalates, replacement flame retardants (RFRs), perfluoroalkyl substances (PFASs), synthetic fragrances, and environmental phenols and estimated pooled geometric means (GMs) and 95% confidence intervals for 45 chemicals measured in ≥3 data sets. In order to rank and contextualize these results, we used the pooled GMs to calculate residential intake from dust ingestion, inhalation, and dermal uptake from air, and then identified hazard traits from the Safer Consumer Products Candidate Chemical List. Our results indicate that U.S. indoor dust consistently contains chemicals from multiple classes. Phthalates occurred in the highest concentrations, followed by phenols, RFRs, fragrance, and PFASs. Several phthalates and RFRs had the highest residential intakes. We also found that many chemicals in dust share hazard traits such as reproductive and endocrine toxicity. We offer recommendations to maximize comparability of studies and advance indoor exposure science. This information is critical in shaping future exposure and health studies, especially related to cumulative exposures, and in providing evidence for intervention development and public policy. PMID:27623734

Global metabolic rewiring for improved CO2 fixation and chemical production in cyanobacteria

NASA Astrophysics Data System (ADS)

Kanno, Masahiro; Carroll, Austin L.; Atsumi, Shota

2017-03-01

Cyanobacteria have attracted much attention as hosts to recycle CO2 into valuable chemicals. Although cyanobacteria have been engineered to produce various compounds, production efficiencies are too low for commercialization. Here we engineer the carbon metabolism of Synechococcus elongatus PCC 7942 to improve glucose utilization, enhance CO2 fixation and increase chemical production. We introduce modifications in glycolytic pathways and the Calvin Benson cycle to increase carbon flux and redirect it towards carbon fixation. The engineered strain efficiently uses both CO2 and glucose, and produces 12.6 g l-1 of 2,3-butanediol with a rate of 1.1 g l-1 d-1 under continuous light conditions. Removal of native regulation enables carbon fixation and 2,3-butanediol production in the absence of light. This represents a significant step towards industrial viability and an excellent example of carbon metabolism plasticity.

Optimization of enzyme parameters for fermentative production of biorenewable fuels and chemicals

PubMed Central

Jarboe, Laura R.; Liu, Ping; Kautharapu, Kumar Babu; Ingram, Lonnie O.

2012-01-01

Microbial biocatalysts such as Escherichia coli and Saccharomyces cerevisiae have been extensively subjected to Metabolic Engineering for the fermentative production of biorenewable fuels and chemicals. This often entails the introduction of new enzymes, deletion of unwanted enzymes and efforts to fine-tune enzyme abundance in order to attain the desired strain performance. Enzyme performance can be quantitatively described in terms of the Michaelis-Menten type parameters Km, turnover number kcat and Ki, which roughly describe the affinity of an enzyme for its substrate, the speed of a reaction and the enzyme sensitivity to inhibition by regulatory molecules. Here we describe examples of where knowledge of these parameters have been used to select, evolve or engineer enzymes for the desired performance and enabled increased production of biorenewable fuels and chemicals. Examples include production of ethanol, isobutanol, 1-butanol and tyrosine and furfural tolerance. The Michaelis-Menten parameters can also be used to judge the cofactor dependence of enzymes and quantify their preference for NADH or NADPH. Similarly, enzymes can be selected, evolved or engineered for the preferred cofactor preference. Examples of exporter engineering and selection are also discussed in the context of production of malate, valine and limonene. PMID:24688665

Determination of trace amounts of chemical warfare agent degradation products in decontamination solutions with NMR spectroscopy.

PubMed

Koskela, Harri; Rapinoja, Marja-Leena; Kuitunen, Marja-Leena; Vanninen, Paula

2007-12-01

Decontamination solutions are used for an efficient detoxification of chemical warfare agents (CWAs). As these solutions can be composed of strong alkaline chemicals with hydrolyzing and oxidizing properties, the analysis of CWA degradation products in trace levels from these solutions imposes a challenge for any analytical technique. Here, we present results of application of nuclear magnetic resonance spectroscopy for analysis of trace amounts of CWA degradation products in several untreated decontamination solutions. Degradation products of the nerve agents sarin, soman, and VX were selectively monitored with substantially reduced interference of background signals by 1D 1H-31P heteronuclear single quantum coherence (HSQC) spectrometry. The detection limit of the chemicals was at the low part-per-million level (2-10 microg/mL) in all studied solutions. In addition, the concentration of the degradation products was obtained with sufficient confidence with external standards.

Low-Carbon Fuel and Chemical Production by Anaerobic Gas Fermentation.

PubMed

Daniell, James; Nagaraju, Shilpa; Burton, Freya; Köpke, Michael; Simpson, Séan Dennis

World energy demand is expected to increase by up to 40% by 2035. Over this period, the global population is also expected to increase by a billion people. A challenge facing the global community is not only to increase the supply of fuel, but also to minimize fossil carbon emissions to safeguard the environment, at the same time as ensuring that food production and supply is not detrimentally impacted. Gas fermentation is a rapidly maturing technology which allows low carbon fuel and commodity chemical synthesis. Unlike traditional biofuel technologies, gas fermentation avoids the use of sugars, relying instead on gas streams rich in carbon monoxide and/or hydrogen and carbon dioxide as sources of carbon and energy for product synthesis by specialized bacteria collectively known as acetogens. Thus, gas fermentation enables access to a diverse array of novel, large volume, and globally available feedstocks including industrial waste gases and syngas produced, for example, via the gasification of municipal waste and biomass. Through the efforts of academic labs and early stage ventures, process scale-up challenges have been surmounted through the development of specialized bioreactors. Furthermore, tools for the genetic improvement of the acetogenic bacteria have been reported, paving the way for the production of a spectrum of ever-more valuable products via this process. As a result of these developments, interest in gas fermentation among both researchers and legislators has grown significantly in the past 5 years to the point that this approach is now considered amongst the mainstream of emerging technology solutions for near-term low-carbon fuel and chemical synthesis.

Sampling the stratum corneum for toxic chemicals.

PubMed

Coman, Garrett; Blickenstaff, Nicholas R; Blattner, Collin M; Andersen, Rosa; Maibach, Howard I

2014-01-01

Dermal exposure is an important pathway in environmental health. Exposure comes from contaminated water, soil, treated surfaces, textiles, aerosolized chemicals, and agricultural products. It can occur in homes, schools, play areas, and work settings in the form of industrial sources, consumer products, or hazardous wastes. Dermal exposure is most likely to occur through contact with liquids, water, soil, sediment, and contaminated surfaces. The ability to detect and measure exposure to toxic materials on the skin is an important environmental health issue. The stratum corneum is the skin's first and principal barrier layer of protection from the outside world. It has a complex structure that can effectively protect against a wide variety of physical, chemical, and biological contaminants. However, there are a variety of chemical agents that can damage the stratum corneum and the underlying epidermis, dermis and subcutis, and/or enter systemic circulation through the skin. There are numerous ways of sampling the stratum corneum for these toxic materials like abrasion techniques, biopsy, suction blistering, imaging, washing, wipe sampling, tape stripping, and spot testing. Selecting a method likely depends on the particular needs of the situation. Hence, there is a need to review practical considerations for their use in sampling the stratum corneum for toxins.

Flavour chemicals in a sample of non-cigarette tobacco products without explicit flavour names sold in New York City in 2015

PubMed Central

Farley, Shannon M; Schroth, Kevin RJ; Grimshaw, Victoria; Luo, Wentai; DeGagne, Julia L; Tierney, Peyton A; Kim, Kilsun; Pankow, James F

2018-01-01

Background Youth who experiment with tobacco often start with flavoured products. In New York City (NYC), local law restricts sales of all tobacco products with ‘characterising flavours’ except for ‘tobacco, menthol, mint and wintergreen’. Enforcement is based on packaging: explicit use of a flavour name (eg, ‘strawberry’) or image depicting a flavour (eg, a fruit) is presumptive evidence that a product is flavoured and therefore prohibited. However, a tobacco product may contain significant levels of added flavour chemicals even when the label does not explicitly use a flavour name. Methods Sixteen tobacco products were purchased within NYC in 2015 that did not have explicit flavour names, along with three with flavour names. These were analysed for 92 known flavour chemicals plus triacetin by gas chromatography/mass spectrometry. Results 14 of the 16 products had total determined flavour chemical levels that were higher (>0.3 mg/g) than in previously studied flavour-labelled products and of a chemical profile indicating added flavour chemicals. Conclusions The results suggest that the tobacco industry has responded to sales restrictions by renaming flavoured products to avoid explicitly identifying them as flavoured. While chemical analysis is the most precise means of identifying flavours in tobacco products, federal tobacco laws pre-empt localities from basing regulations on that approach, limiting enforcement options. If the Food and Drug Administration would mandate that all tobacco products must indicate when flavourings are present above a specific level, local jurisdictions could enforce their sales restrictions. A level of 0.1 mg/g for total added flavour chemicals is suggested here as a relevant reference value for regulating added flavour chemicals in tobacco products. PMID:28400490

Cell-free metabolic engineering: production of chemicals by minimized reaction cascades.

PubMed

Guterl, Jan-Karl; Garbe, Daniel; Carsten, Jörg; Steffler, Fabian; Sommer, Bettina; Reiße, Steven; Philipp, Anja; Haack, Martina; Rühmann, Broder; Koltermann, Andre; Kettling, Ulrich; Brück, Thomas; Sieber, Volker

2012-11-01

The limited supply of fossil resources demands the development of renewable alternatives to petroleum-based products. Here, biobased higher alcohols such as isobutanol are versatile platform molecules for the synthesis of chemical commodities and fuels. Currently, their fermentation-based production is limited by the low tolerance of microbial production systems to the end products and also by the low substrate flux into cell metabolism. We developed an innovative cell-free approach, utilizing an artificial minimized glycolytic reaction cascade that only requires one single coenzyme. Using this toolbox the cell-free production of ethanol and isobutanol from glucose was achieved. We also confirmed that these streamlined cascades functioned under conditions at which microbial production would have ceased. Our system can be extended to an array of industrially-relevant molecules. Application of solvent-tolerant biocatalysts potentially allows for high product yields, which significantly simplifies downstream product recovery. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Damage to the anterior arcuate fasciculus predicts non-fluent speech production in aphasia.

PubMed

Fridriksson, Julius; Guo, Dazhou; Fillmore, Paul; Holland, Audrey; Rorden, Chris

2013-11-01

Non-fluent aphasia implies a relatively straightforward neurological condition characterized by limited speech output. However, it is an umbrella term for different underlying impairments affecting speech production. Several studies have sought the critical lesion location that gives rise to non-fluent aphasia. The results have been mixed but typically implicate anterior cortical regions such as Broca's area, the left anterior insula, and deep white matter regions. To provide a clearer picture of cortical damage in non-fluent aphasia, the current study examined brain damage that negatively influences speech fluency in patients with aphasia. It controlled for some basic speech and language comprehension factors in order to better isolate the contribution of different mechanisms to fluency, or its lack. Cortical damage was related to overall speech fluency, as estimated by clinical judgements using the Western Aphasia Battery speech fluency scale, diadochokinetic rate, rudimentary auditory language comprehension, and executive functioning (scores on a matrix reasoning test) in 64 patients with chronic left hemisphere stroke. A region of interest analysis that included brain regions typically implicated in speech and language processing revealed that non-fluency in aphasia is primarily predicted by damage to the anterior segment of the left arcuate fasciculus. An improved prediction model also included the left uncinate fasciculus, a white matter tract connecting the middle and anterior temporal lobe with frontal lobe regions, including the pars triangularis. Models that controlled for diadochokinetic rate, picture-word recognition, or executive functioning also revealed a strong relationship between anterior segment involvement and speech fluency. Whole brain analyses corroborated the findings from the region of interest analyses. An additional exploratory analysis revealed that involvement of the uncinate fasciculus adjudicated between Broca's and global aphasia

Damage to the anterior arcuate fasciculus predicts non-fluent speech production in aphasia

PubMed Central

Guo, Dazhou; Fillmore, Paul; Holland, Audrey; Rorden, Chris

2013-01-01

Non-fluent aphasia implies a relatively straightforward neurological condition characterized by limited speech output. However, it is an umbrella term for different underlying impairments affecting speech production. Several studies have sought the critical lesion location that gives rise to non-fluent aphasia. The results have been mixed but typically implicate anterior cortical regions such as Broca’s area, the left anterior insula, and deep white matter regions. To provide a clearer picture of cortical damage in non-fluent aphasia, the current study examined brain damage that negatively influences speech fluency in patients with aphasia. It controlled for some basic speech and language comprehension factors in order to better isolate the contribution of different mechanisms to fluency, or its lack. Cortical damage was related to overall speech fluency, as estimated by clinical judgements using the Western Aphasia Battery speech fluency scale, diadochokinetic rate, rudimentary auditory language comprehension, and executive functioning (scores on a matrix reasoning test) in 64 patients with chronic left hemisphere stroke. A region of interest analysis that included brain regions typically implicated in speech and language processing revealed that non-fluency in aphasia is primarily predicted by damage to the anterior segment of the left arcuate fasciculus. An improved prediction model also included the left uncinate fasciculus, a white matter tract connecting the middle and anterior temporal lobe with frontal lobe regions, including the pars triangularis. Models that controlled for diadochokinetic rate, picture-word recognition, or executive functioning also revealed a strong relationship between anterior segment involvement and speech fluency. Whole brain analyses corroborated the findings from the region of interest analyses. An additional exploratory analysis revealed that involvement of the uncinate fasciculus adjudicated between Broca’s and global aphasia

Modeling of the HiPco process for carbon nanotube production. I. Chemical kinetics

NASA Technical Reports Server (NTRS)

Dateo, Christopher E.; Gokcen, Tahir; Meyyappan, M.

2002-01-01

A chemical kinetic model is developed to help understand and optimize the production of single-walled carbon nanotubes via the high-pressure carbon monoxide (HiPco) process, which employs iron pentacarbonyl as the catalyst precursor and carbon monoxide as the carbon feedstock. The model separates the HiPco process into three steps, precursor decomposition, catalyst growth and evaporation, and carbon nanotube production resulting from the catalyst-enhanced disproportionation of carbon monoxide, known as the Boudouard reaction: 2 CO(g)-->C(s) + CO2(g). The resulting detailed model contains 971 species and 1948 chemical reactions. A second model with a reduced reaction set containing 14 species and 22 chemical reactions is developed on the basis of the detailed model and reproduces the chemistry of the major species. Results showing the parametric dependence of temperature, total pressure, and initial precursor partial pressures are presented, with comparison between the two models. The reduced model is more amenable to coupled reacting flow-field simulations, presented in the following article.

Charting, navigating, and populating natural product chemical space for drug discovery.

PubMed

Lachance, Hugo; Wetzel, Stefan; Kumar, Kamal; Waldmann, Herbert

2012-07-12

Natural products are a heterogeneous group of compounds with diverse, yet particular molecular properties compared to synthetic compounds and drugs. All relevant analyses show that natural products indeed occupy parts of chemical space not explored by available screening collections while at the same time largely adhering to the rule-of-five. This renders them a valuable, unique, and necessary component of screening libraries used in drug discovery. With ChemGPS-NP on the Web and Scaffold Hunter two tools are available to the scientific community to guide exploration of biologically relevant NP chemical space in a focused and targeted fashion with a view to guide novel synthesis approaches. Several of the examples given illustrate the possibility of bridging the gap between computational methods and compound library synthesis and the possibility of integrating cheminformatics and chemical space analyses with synthetic chemistry and biochemistry to successfully explore chemical space for the identification of novel small molecule modulators of protein function.The examples also illustrate the synergistic potential of the chemical space concept and modern chemical synthesis for biomedical research and drug discovery. Chemical space analysis can map under explored biologically relevant parts of chemical space and identify the structure types occupying these parts. Modern synthetic methodology can then be applied to efficiently fill this “virtual space” with real compounds.From a cheminformatics perspective, there is a clear demand for open-source and easy to use tools that can be readily applied by educated nonspecialist chemists and biologists in their daily research. This will include further development of Scaffold Hunter, ChemGPS-NP, and related approaches on the Web. Such a “cheminformatics toolbox” would enable chemists and biologists to mine their own data in an intuitive and highly interactive process and without the need for specialized computer

Advancing Consumer Product Composition and Chemical Use Information to Facilitate Risk-Based Decision Making

EPA Science Inventory

This presentation describes EPA efforts to collect, model, and measure publically available consumer product data for use in exposure assessment. The development of the ORD Chemicals and Products database will be described, as will machine-learning based models for predicting ch...

FIBER OPTIC BIOSENSOR FOR DNA DAMAGE

EPA Science Inventory

This paper describes a fiber optic biosensor for the rapid and sensitive detection of radiation-induced or chemically-induced oxidative DNA damage. The assay is based on the hybridization and temperature-induced dissociation (melting curves) of synthetic oligonucleotides. The...

Toward crustacean without chemicals: a descriptive analysis of consumer response using price comparisons

PubMed Central

Okpala, Charles Odilichukwu R.; Bono, Gioacchino; Pipitone, Vito; Vitale, Sergio; Cannizzaro, Leonardo

2016-01-01

Background To date, there seems to be limited-to-zero emphasis about how consumers perceive crustacean products subject to either chemical and or non-chemical preservative treatments. In addition, studies that investigated price comparisons of crustacean products subject to either chemical or chemical-free preservative methods seem unreported. Objective This study focused on providing some foundational knowledge about how consumers perceive traditionally harvested crustaceans that are either chemical-treated and or free of chemicals, incorporating price comparisons using a descriptive approach. Design The study design employed a questionnaire approach via interview using a computer-assisted telephone system and sampled 1,540 participants across five key locations in Italy. To actualize consumer sensitivity, ‘price’ was the focus given its crucial role as a consumption barrier. Prior to this, variables such as demographic characteristics of participants, frequency of purchasing, quality attributes/factors that limit the consumption of crustaceans were equally considered. Results By price comparisons, consumers are likely to favor chemical-free (modified atmosphere packaging) crustacean products amid a price increase of up to 15%. But, a further price increase such as by 25% could markedly damage consumers’ feelings, which might lead to a considerable number opting out in favor of either chemical-treated or other seafood products. Comparing locations, the studied variables showed no statistical differences (p>0.05). On the contrary, the response weightings fluctuated across the studied categories. Both response weightings and coefficient of variation helped reveal more about how responses deviated per variable categories. Conclusions This study has revealed some foundational knowledge about how consumers perceive traditionally harvested crustaceans that were either chemical-treated or subject to chemical-free preservative up to price sensitivity using Italy as

Suitability of macrophage inflammatory protein-1beta production by THP-1 cells in differentiating skin sensitizers from irritant chemicals.

PubMed

Lim, Yeon-Mi; Moon, Seong-Joon; An, Su-Sun; Lee, Soo-Jin; Kim, Seo-Young; Chang, Ih-Seop; Park, Kui-Lea; Kim, Hyoung-Ah; Heo, Yong

2008-04-01

Worldwide restrictions in animal use for research have driven efforts to develop alternative methods. The study aimed to test the efficacy of the macrophage inflammatory protein-1beta (MIP-1beta) assay for testing chemicals' skin-sensitizing capacity. The assay was performed using 9 chemicals judged to be sensitizing and 7 non-sensitizing by the standard in vivo assays. THP-1 cells were cultured in the presence or absence of 4 doses, 0.01x, 0.1x, 0.5x, or 1x IC(50) (50% inhibitory concentration for THP-1 cell proliferation) of these chemicals for 24 hr, and the MIP-1beta level in the supernatants was determined. Skin sensitization by the test chemicals was determined by MIP-1beta production rates. The MIP-1beta production rate was expressed as the relative increase in MIP-1beta production in response to chemical treatment compared with vehicle treatment. When the threshold MIP-1beta production rate used was 100% or 105% of dimethyl sulfoxide, all the sensitizing chemicals tested (dinitrochlorobenzene, hexyl cinnamic aldehyde, eugenol, hydroquinone, dinitrofluorobenzene, benzocaine, nickel, chromium, and 5-chloro-2-methyl-4-isothiazolin-3-one) were positive, and all the non-sensitizing chemicals (methyl salicylate, benzalkonium chloride, lactic acid, isopropanol, and salicylic acid), with the exception of sodium lauryl sulfate, were negative for MIP-1beta production. These results indicate that MIP-1beta could be a biomarker for classification of chemicals as sensitizers or non-sensitizers.

Specific chemical and structural damage to proteins produced by synchrotron radiation.

PubMed

Weik, M; Ravelli, R B; Kryger, G; McSweeney, S; Raves, M L; Harel, M; Gros, P; Silman, I; Kroon, J; Sussman, J L

2000-01-18

Radiation damage is an inherent problem in x-ray crystallography. It usually is presumed to be nonspecific and manifested as a gradual decay in the overall quality of data obtained for a given crystal as data collection proceeds. Based on third-generation synchrotron x-ray data, collected at cryogenic temperatures, we show for the enzymes Torpedo californica acetylcholinesterase and hen egg white lysozyme that synchrotron radiation also can cause highly specific damage. Disulfide bridges break, and carboxyl groups of acidic residues lose their definition. Highly exposed carboxyls, and those in the active site of both enzymes, appear particularly susceptible. The catalytic triad residue, His-440, in acetylcholinesterase, also appears to be much more sensitive to radiation damage than other histidine residues. Our findings have direct practical implications for routine x-ray data collection at high-energy synchrotron sources. Furthermore, they provide a direct approach for studying the radiation chemistry of proteins and nucleic acids at a detailed, structural level and also may yield information concerning putative "weak links" in a given biological macromolecule, which may be of structural and functional significance.

Loss of regional accent after damage to the speech production network.

PubMed

Berthier, Marcelo L; Dávila, Guadalupe; Moreno-Torres, Ignacio; Beltrán-Corbellini, Álvaro; Santana-Moreno, Daniel; Roé-Vellvé, Núria; Thurnhofer-Hemsi, Karl; Torres-Prioris, María José; Massone, María Ignacia; Ruiz-Cruces, Rafael

2015-01-01

Lesion-symptom mapping studies reveal that selective damage to one or more components of the speech production network can be associated with foreign accent syndrome, changes in regional accent (e.g., from Parisian accent to Alsatian accent), stronger regional accent, or re-emergence of a previously learned and dormant regional accent. Here, we report loss of regional accent after rapidly regressive Broca's aphasia in three Argentinean patients who had suffered unilateral or bilateral focal lesions in components of the speech production network. All patients were monolingual speakers with three different native Spanish accents (Cordobés or central, Guaranítico or northeast, and Bonaerense). Samples of speech production from the patient with native Córdoba accent were compared with previous recordings of his voice, whereas data from the patient with native Guaranítico accent were compared with speech samples from one healthy control matched for age, gender, and native accent. Speech samples from the patient with native Buenos Aires's accent were compared with data obtained from four healthy control subjects with the same accent. Analysis of speech production revealed discrete slowing in speech rate, inappropriate long pauses, and monotonous intonation. Phonemic production remained similar to those of healthy Spanish speakers, but phonetic variants peculiar to each accent (e.g., intervocalic aspiration of /s/ in Córdoba accent) were absent. While basic normal prosodic features of Spanish prosody were preserved, features intrinsic to melody of certain geographical areas (e.g., rising end F0 excursion in declarative sentences intoned with Córdoba accent) were absent. All patients were also unable to produce sentences with different emotional prosody. Brain imaging disclosed focal left hemisphere lesions involving the middle part of the motor cortex, the post-central cortex, the posterior inferior and/or middle frontal cortices, insula, anterior putamen and

Loss of regional accent after damage to the speech production network

PubMed Central

Berthier, Marcelo L.; Dávila, Guadalupe; Moreno-Torres, Ignacio; Beltrán-Corbellini, Álvaro; Santana-Moreno, Daniel; Roé-Vellvé, Núria; Thurnhofer-Hemsi, Karl; Torres-Prioris, María José; Massone, María Ignacia; Ruiz-Cruces, Rafael

2015-01-01

Lesion-symptom mapping studies reveal that selective damage to one or more components of the speech production network can be associated with foreign accent syndrome, changes in regional accent (e.g., from Parisian accent to Alsatian accent), stronger regional accent, or re-emergence of a previously learned and dormant regional accent. Here, we report loss of regional accent after rapidly regressive Broca’s aphasia in three Argentinean patients who had suffered unilateral or bilateral focal lesions in components of the speech production network. All patients were monolingual speakers with three different native Spanish accents (Cordobés or central, Guaranítico or northeast, and Bonaerense). Samples of speech production from the patient with native Córdoba accent were compared with previous recordings of his voice, whereas data from the patient with native Guaranítico accent were compared with speech samples from one healthy control matched for age, gender, and native accent. Speech samples from the patient with native Buenos Aires’s accent were compared with data obtained from four healthy control subjects with the same accent. Analysis of speech production revealed discrete slowing in speech rate, inappropriate long pauses, and monotonous intonation. Phonemic production remained similar to those of healthy Spanish speakers, but phonetic variants peculiar to each accent (e.g., intervocalic aspiration of /s/ in Córdoba accent) were absent. While basic normal prosodic features of Spanish prosody were preserved, features intrinsic to melody of certain geographical areas (e.g., rising end F0 excursion in declarative sentences intoned with Córdoba accent) were absent. All patients were also unable to produce sentences with different emotional prosody. Brain imaging disclosed focal left hemisphere lesions involving the middle part of the motor cortex, the post-central cortex, the posterior inferior and/or middle frontal cortices, insula, anterior putamen and

Evaluating exposures to complex mixtures of chemicals during a new production process in the plastics industry.

PubMed

Meijster, Tim; Burstyn, Igor; Van Wendel De Joode, Berna; Posthumus, Maarten A; Kromhout, Hans

2004-08-01

The goal of this study was to monitor emission of chemicals at a factory where plastics products were fabricated by a new robotic (impregnated tape winding) production process. Stationary and personal air measurements were taken to determine which chemicals were released and at what concentrations. Principal component analyses (PCA) and linear regression were used to determine the emission sources of different chemicals found in the air samples. We showed that complex mixtures of chemicals were released, but most concentrations were below Dutch exposure limits. Based on the results of the principal component analyses, the chemicals found were divided into three groups. The first group consisted of short chain aliphatic hydrocarbons (C2-C6). The second group included larger hydrocarbons (C9-C11) and some cyclic hydrocarbons. The third group contained all aromatic and two aliphatic hydrocarbons. Regression analyses showed that emission of the first group of chemicals was associated with cleaning activities and the use of epoxy resins. The second and third group showed strong association with the type of tape used in the new tape winding process. High levels of CO and HCN (above exposure limits) were measured on one occasion when a different brand of impregnated polypropylene sulphide tape was used in the tape winding process. Plans exist to drastically increase production with the new tape winding process. This will cause exposure levels to rise and therefore further control measures should be installed to reduce release of these chemicals.

Artisanal Sonoran cheese (Cocido cheese): an exploration of its production process, chemical composition and microbiological quality.

PubMed

Cuevas-González, Paúl F; Heredia-Castro, Priscilia Y; Méndez-Romero, José I; Hernández-Mendoza, Adrián; Reyes-Díaz, Ricardo; Vallejo-Cordoba, Belinda; González-Córdova, Aarón F

2017-10-01

The objective of this study was to explore and document the production process of artisanal Cocido cheese and to determine its chemical composition and microbiological quality, considering samples from six dairies and four retailers. Cocido cheese is a semi-hard (506-555 g kg -1 of moisture), medium fat (178.3-219.1 g kg -1 ), pasta filata-type cheese made from raw whole cow's milk. The production process is not standardized and therefore the chemical and microbiological components of the sampled cheeses varied. Indicator microorganisms significantly decreased (P < 0.05) during the processing of Cocido cheese. Salmonella spp. were not found during the production process, and both Listeria monocytogenes and staphylococcal enterotoxin were absent in the final cheeses. This study provides more information on one of the most popular artisanal cheeses with high cultural value and economic impact in northwestern Mexico. In view of the foregoing, good manufacturing practices need to be implemented for the manufacture of Cocido cheese. Also, it is of utmost importance to make sure that the heat treatment applied for cooking the curd ensures a phosphatase-negative test, otherwise it would be necessary to pasteurize milk. Nevertheless, since Cocido cheese is a non-ripened, high-moisture product, it is a highly perishable product that could present a health risk if not properly handled. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Global metabolic rewiring for improved CO2 fixation and chemical production in cyanobacteria.

PubMed

Kanno, Masahiro; Carroll, Austin L; Atsumi, Shota

2017-03-13

Cyanobacteria have attracted much attention as hosts to recycle CO 2 into valuable chemicals. Although cyanobacteria have been engineered to produce various compounds, production efficiencies are too low for commercialization. Here we engineer the carbon metabolism of Synechococcus elongatus PCC 7942 to improve glucose utilization, enhance CO 2 fixation and increase chemical production. We introduce modifications in glycolytic pathways and the Calvin Benson cycle to increase carbon flux and redirect it towards carbon fixation. The engineered strain efficiently uses both CO 2 and glucose, and produces 12.6 g l -1 of 2,3-butanediol with a rate of 1.1 g l -1  d -1 under continuous light conditions. Removal of native regulation enables carbon fixation and 2,3-butanediol production in the absence of light. This represents a significant step towards industrial viability and an excellent example of carbon metabolism plasticity.

EFFECTS OF ENDOCRINE DISRUPTING CHEMICALS (EDCS) ON FETAL TESTES HORMONE PRODUCTION

EPA Science Inventory

Effects of Endocrine Disrupting Chemicals (EDCs) on Fetal Testes Hormone Production
CS Lambright, VS Wilson, JR Furr, CJ Wolf, N Noriega, LE Gray, Jr
US EPA, ORD/NHEERL/RTD, RTP, NC 27711

Exposure to EDCs during critical periods of fetal sexual development can have...

Prediction of Hydrolysis Products of Organic Chemicals under Environmental pH Conditions

EPA Science Inventory

Cheminformatics-based software tools can predict the molecular structure of transformation products using a library of transformation reaction schemes. This paper presents the development of such a library for abiotic hydrolysis of organic chemicals under environmentally relevant...

Chemically-bonded brick production based on burned clay by means of semidry pressing

NASA Astrophysics Data System (ADS)

Voroshilov, Ivan; Endzhievskaya, Irina; Vasilovskaya, Nina

2016-01-01

We presented a study on the possibility of using the burnt rocks of the Krasnoyarsk Territory for production of chemically-bonded materials in the form of bricks which are so widely used in multistory housing and private house construction. The radiographic analysis of the composition of burnt rock was conducted and a modifier to adjust the composition uniformity was identified. The mixing moisture content was identified and optimal amount at 13-15% was determined. The method of semidry pressing has been chosen. The process of obtaining moldings has been theoretically proved; the advantages of chemically-bonded wall materials compared to ceramic brick were shown. The production of efficient artificial stone based on material burnt rocks, which is comparable with conventionally effective ceramic materials or effective with cell tile was proved, the density of the burned clay-based cell tile makes up to 1630-1785 kg m3, with compressive strength of 13.6-20.0 MPa depending on the compression ratio and cement consumption, frost resistance index is F50, and the thermal conductivity in the masonry is λ = 0,459-0,546 W m * °C. The clear geometric dimensions of pressed products allow the use of the chemically-bonded brick based on burnt clay as a facing brick.

Alkali production associated with malolactic fermentation by oral streptococci and protection against acid, oxidative, or starvation damage

PubMed Central

Sheng, Jiangyun; Baldeck, Jeremiah D.; Nguyen, Phuong T.M.; Quivey, Robert G.; Marquis, Robert E.

2011-01-01

Alkali production by oral streptococci is considered important for dental plaque ecology and caries moderation. Recently, malolactic fermentation (MLF) was identified as a major system for alkali production by oral streptococci, including Streptococcus mutans. Our major objectives in the work described in this paper were to further define the physiology and genetics of MLF of oral streptococci and its roles in protection against metabolic stress damage. l-Malic acid was rapidly fermented to l-lactic acid and CO2 by induced cells of wild-type S. mutans, but not by deletion mutants for mleS (malolactic enzyme) or mleP (malate permease). Mutants for mleR (the contiguous regulator gene) had intermediate capacities for MLF. Loss of capacity to catalyze MLF resulted in loss of capacity for protection against lethal acidification. MLF was also found to be protective against oxidative and starvation damage. The capacity of S. mutans to produce alkali from malate was greater than its capacity to produce acid from glycolysis at low pH values of 4 or 5. MLF acted additively with the arginine deiminase system for alkali production by Streptococcus sanguinis, but not with urease of Streptococcus salivarius. Malolactic fermentation is clearly a major process for alkali generation by oral streptococci and for protection against environmental stresses. PMID:20651853

Alkali production associated with malolactic fermentation by oral streptococci and protection against acid, oxidative, or starvation damage.

PubMed

Sheng, Jiangyun; Baldeck, Jeremiah D; Nguyen, Phuong T M; Quivey, Robert G; Marquis, Robert E

2010-07-01

Alkali production by oral streptococci is considered important for dental plaque ecology and caries moderation. Recently, malolactic fermentation (MLF) was identified as a major system for alkali production by oral streptococci, including Streptococcus mutans. Our major objectives in the work described in this paper were to further define the physiology and genetics of MLF of oral streptococci and its roles in protection against metabolic stress damage. L-Malic acid was rapidly fermented to L-lactic acid and CO(2) by induced cells of wild-type S. mutans, but not by deletion mutants for mleS (malolactic enzyme) or mleP (malate permease). Mutants for mleR (the contiguous regulator gene) had intermediate capacities for MLF. Loss of capacity to catalyze MLF resulted in loss of capacity for protection against lethal acidification. MLF was also found to be protective against oxidative and starvation damage. The capacity of S. mutans to produce alkali from malate was greater than its capacity to produce acid from glycolysis at low pH values of 4 or 5. MLF acted additively with the arginine deiminase system for alkali production by Streptococcus sanguinis, but not with urease of Streptococcus salivarius. Malolactic fermentation is clearly a major process for alkali generation by oral streptococci and for protection against environmental stresses.

Flavour chemicals in a sample of non-cigarette tobacco products without explicit flavour names sold in New York City in 2015.

PubMed

Farley, Shannon M; Schroth, Kevin Rj; Grimshaw, Victoria; Luo, Wentai; DeGagne, Julia L; Tierney, Peyton A; Kim, Kilsun; Pankow, James F

2018-03-01

Youth who experiment with tobacco often start with flavoured products. In New York City (NYC), local law restricts sales of all tobacco products with 'characterising flavours' except for 'tobacco, menthol, mint and wintergreen'. Enforcement is based on packaging: explicit use of a flavour name (eg, 'strawberry') or image depicting a flavour (eg, a fruit) is presumptive evidence that a product is flavoured and therefore prohibited. However, a tobacco product may contain significant levels of added flavour chemicals even when the label does not explicitly use a flavour name. Sixteen tobacco products were purchased within NYC in 2015 that did not have explicit flavour names, along with three with flavour names. These were analysed for 92 known flavour chemicals plus triacetin by gas chromatography/mass spectrometry. 14 of the 16 products had total determined flavour chemical levels that were higher (>0.3 mg/g) than in previously studied flavour-labelled products and of a chemical profile indicating added flavour chemicals. The results suggest that the tobacco industry has responded to sales restrictions by renaming flavoured products to avoid explicitly identifying them as flavoured. While chemical analysis is the most precise means of identifying flavours in tobacco products, federal tobacco laws pre-empt localities from basing regulations on that approach, limiting enforcement options. If the Food and Drug Administration would mandate that all tobacco products must indicate when flavourings are present above a specific level, local jurisdictions could enforce their sales restrictions. A level of 0.1 mg/g for total added flavour chemicals is suggested here as a relevant reference value for regulating added flavour chemicals in tobacco products. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Oxaloacetate Ameliorates Chemical Liver Injury via Oxidative Stress Reduction and Enhancement of Bioenergetic Fluxes.

PubMed

Kuang, Ye; Han, Xiaoyun; Xu, Mu; Wang, Yue; Zhao, Yuxiang; Yang, Qing

2018-05-31

Chemical injury is partly due to free radical lipid peroxidation, which can induce oxidative stress and produce a large number of reactive oxygen species (ROS). Oxaloacetic acid is an important intermediary in the tricarboxylic acid cycle (TCA cycle) and participates in metabolism and energy production. In our study, we found that oxaloacetate (OA) effectively alleviated liver injury which was induced by hydrogen peroxide (H₂O₂) in vitro and carbon tetrachloride (CCl₄) in vivo. OA scavenged ROS, prevented oxidative damage and maintained the normal structure of mitochondria. We further confirmed that OA increased adenosine triphosphate (ATP) by promoting the TCA production cycle and oxidative phosphorylation (OXPHOS). Finally, OA inhibited the mitogen-activated protein kinase (MAPK) and apoptotic pathways by suppressing tumor necrosis factor-α (TNF-α). Our findings reveal a mechanism for OA ameliorating chemical liver injury and suggest a possible implementation for preventing the chemical liver injury.

Mechanisms of free radical-induced damage to DNA.

PubMed

Dizdaroglu, Miral; Jaruga, Pawel

2012-04-01

Endogenous and exogenous sources cause free radical-induced DNA damage in living organisms by a variety of mechanisms. The highly reactive hydroxyl radical reacts with the heterocyclic DNA bases and the sugar moiety near or at diffusion-controlled rates. Hydrated electron and H atom also add to the heterocyclic bases. These reactions lead to adduct radicals, further reactions of which yield numerous products. These include DNA base and sugar products, single- and double-strand breaks, 8,5'-cyclopurine-2'-deoxynucleosides, tandem lesions, clustered sites and DNA-protein cross-links. Reaction conditions and the presence or absence of oxygen profoundly affect the types and yields of the products. There is mounting evidence for an important role of free radical-induced DNA damage in the etiology of numerous diseases including cancer. Further understanding of mechanisms of free radical-induced DNA damage, and cellular repair and biological consequences of DNA damage products will be of outmost importance for disease prevention and treatment.

Dissecting the Molecular Mechanism of Ionizing Radiation-Induced Tissue Damage in the Feather Follicle

PubMed Central

Chen, Xi; Liao, Chunyan; Chu, Qiqi; Zhou, Guixuan; Lin, Xiang; Li, Xiaobo; Lu, Haijie; Xu, Benhua; Yue, Zhicao

2014-01-01

Ionizing radiation (IR) is a common therapeutic agent in cancer therapy. It damages normal tissue and causes side effects including dermatitis and mucositis. Here we use the feather follicle as a model to investigate the mechanism of IR-induced tissue damage, because any perturbation of feather growth will be clearly recorded in its regular yet complex morphology. We find that IR induces defects in feather formation in a dose-dependent manner. No abnormality was observed at 5 Gy. A transient, reversible perturbation of feather growth was induced at 10 Gy, leading to defects in the feather structure. This perturbation became irreversible at 20 Gy. Molecular and cellular analysis revealed P53 activation, DNA damage and repair, cell cycle arrest and apoptosis in the pathobiology. IR also induces patterning defects in feather formation, with disrupted branching morphogenesis. This perturbation is mediated by cytokine production and Stat1 activation, as manipulation of cytokine levels or ectopic Stat1 over-expression also led to irregular feather branching. Furthermore, AG-490, a chemical inhibitor of Stat1 signaling, can partially rescue IR-induced tissue damage. Our results suggest that the feather follicle could serve as a useful model to address the in vivo impact of the many mechanisms of IR-induced tissue damage. PMID:24586618

Biomedically relevant chemical and physical properties of coal combustion products.

PubMed Central

Fisher, G L

1983-01-01

The evaluation of the potential public and occupational health hazards of developing and existing combustion processes requires a detailed understanding of the physical and chemical properties of effluents available for human and environmental exposures. These processes produce complex mixtures of gases and aerosols which may interact synergistically or antagonistically with biological systems. Because of the physicochemical complexity of the effluents, the biomedically relevant properties of these materials must be carefully assessed. Subsequent to release from combustion sources, environmental interactions further complicate assessment of the toxicity of combustion products. This report provides an overview of the biomedically relevant physical and chemical properties of coal fly ash. Coal fly ash is presented as a model complex mixture for health and safety evaluation of combustion processes. PMID:6337824

Expansion of chemical space for natural products by uncommon P450 reactions.

PubMed

Zhang, Xingwang; Li, Shengying

2017-08-30

Covering: 2000 to 2017Cytochrome P450 enzymes (P450s) are the most versatile biocatalysts in nature. The catalytic competence of these extraordinary hemoproteins is broadly harnessed by numerous chemical defenders such as bacteria, fungi, and plants for the generation of diverse and complex natural products. Rather than the common tailoring reactions (e.g. hydroxylation and epoxidation) mediated by the majority of biosynthetic P450s, in this review, we will focus on the unusual P450 enzymes in relation to new chemistry, skeleton construction, and structure re-shaping via their own unique catalytic power or the intriguing protein-protein interactions between P450s and other proteins. These uncommon P450 reactions lead to a higher level of chemical space expansion for natural products, through which a broader spectrum of bioactivities can be gained by the host organisms.

78 FR 41768 - Chemical Substances and Mixtures Used in Oil and Gas Exploration or Production; TSCA Section 21...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-11

... Substances and Mixtures Used in Oil and Gas Exploration or Production; TSCA Section 21 Petition; Reasons for... processors of oil and gas exploration and production (E&P) chemical substances and mixtures to maintain... interest to you if you manufacture (including import), process, or distribute chemical substances or...

9 CFR 318.9 - Samples of products, water, dyes, chemicals, etc., to be taken for examination.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Samples of products, water, dyes, chemicals, etc., to be taken for examination. 318.9 Section 318.9 Animals and Animal Products FOOD SAFETY... ESTABLISHMENTS; REINSPECTION AND PREPARATION OF PRODUCTS General § 318.9 Samples of products, water, dyes...

9 CFR 318.9 - Samples of products, water, dyes, chemicals, etc., to be taken for examination.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Samples of products, water, dyes, chemicals, etc., to be taken for examination. 318.9 Section 318.9 Animals and Animal Products FOOD SAFETY... ESTABLISHMENTS; REINSPECTION AND PREPARATION OF PRODUCTS General § 318.9 Samples of products, water, dyes...

9 CFR 318.9 - Samples of products, water, dyes, chemicals, etc., to be taken for examination.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Samples of products, water, dyes, chemicals, etc., to be taken for examination. 318.9 Section 318.9 Animals and Animal Products FOOD SAFETY... ESTABLISHMENTS; REINSPECTION AND PREPARATION OF PRODUCTS General § 318.9 Samples of products, water, dyes...

9 CFR 318.9 - Samples of products, water, dyes, chemicals, etc., to be taken for examination.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Samples of products, water, dyes, chemicals, etc., to be taken for examination. 318.9 Section 318.9 Animals and Animal Products FOOD SAFETY... ESTABLISHMENTS; REINSPECTION AND PREPARATION OF PRODUCTS General § 318.9 Samples of products, water, dyes...

9 CFR 318.9 - Samples of products, water, dyes, chemicals, etc., to be taken for examination.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Samples of products, water, dyes, chemicals, etc., to be taken for examination. 318.9 Section 318.9 Animals and Animal Products FOOD SAFETY... ESTABLISHMENTS; REINSPECTION AND PREPARATION OF PRODUCTS General § 318.9 Samples of products, water, dyes...

Prediction of cancer cell sensitivity to natural products based on genomic and chemical properties.

PubMed

Yue, Zhenyu; Zhang, Wenna; Lu, Yongming; Yang, Qiaoyue; Ding, Qiuying; Xia, Junfeng; Chen, Yan

2015-01-01

Natural products play a significant role in cancer chemotherapy. They are likely to provide many lead structures, which can be used as templates for the construction of novel drugs with enhanced antitumor activity. Traditional research approaches studied structure-activity relationship of natural products and obtained key structural properties, such as chemical bond or group, with the purpose of ascertaining their effect on a single cell line or a single tissue type. Here, for the first time, we develop a machine learning method to comprehensively predict natural products responses against a panel of cancer cell lines based on both the gene expression and the chemical properties of natural products. The results on two datasets, training set and independent test set, show that this proposed method yields significantly better prediction accuracy. In addition, we also demonstrate the predictive power of our proposed method by modeling the cancer cell sensitivity to two natural products, Curcumin and Resveratrol, which indicate that our method can effectively predict the response of cancer cell lines to these two natural products. Taken together, the method will facilitate the identification of natural products as cancer therapies and the development of precision medicine by linking the features of patient genomes to natural product sensitivity.

Identifying chemicals of concern in hydraulic fracturing fluids used for oil production.

PubMed

Stringfellow, William T; Camarillo, Mary Kay; Domen, Jeremy K; Sandelin, Whitney L; Varadharajan, Charuleka; Jordan, Preston D; Reagan, Matthew T; Cooley, Heather; Heberger, Matthew G; Birkholzer, Jens T

2017-01-01

Chemical additives used for hydraulic fracturing and matrix acidizing of oil reservoirs were reviewed and priority chemicals of concern needing further environmental risk assessment, treatment demonstration, or evaluation of occupational hazards were identified. We evaluated chemical additives used for well stimulation in California, the third largest oil producing state in the USA, by the mass and frequency of use, as well as toxicity. The most frequently used chemical additives in oil development were gelling agents, cross-linkers, breakers, clay control agents, iron and scale control agents, corrosion inhibitors, biocides, and various impurities and product stabilizers used as part of commercial mixtures. Hydrochloric and hydrofluoric acids, used for matrix acidizing and other purposes, were reported infrequently. A large number and mass of solvents and surface active agents were used, including quaternary ammonia compounds (QACs) and nonionic surfactants. Acute toxicity was evaluated and many chemicals with low hazard to mammals were identified as potentially hazardous to aquatic environments. Based on an analysis of quantities used, toxicity, and lack of adequate hazard evaluation, QACs, biocides, and corrosion inhibitors were identified as priority chemicals of concern that deserve further investigation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Estimation of the chemical-induced eye injury using a Weight-of-Evidence (WoE) battery of 21 artificial neural network (ANN) c-QSAR models (QSAR-21): part II: corrosion potential.

PubMed

Verma, Rajeshwar P; Matthews, Edwin J

2015-03-01

This is part II of an in silico investigation of chemical-induced eye injury that was conducted at FDA's CFSAN. Serious eye damage caused by chemical (eye corrosion) is assessed using the rabbit Draize test, and this endpoint is an essential part of hazard identification and labeling of industrial and consumer products to ensure occupational and consumer safety. There is an urgent need to develop an alternative to the Draize test because EU's 7th amendment to the Cosmetic Directive (EC, 2003; 76/768/EEC) and recast Regulation now bans animal testing on all cosmetic product ingredients and EU's REACH Program limits animal testing for chemicals in commerce. Although in silico methods have been reported for eye irritation (reversible damage), QSARs specific for eye corrosion (irreversible damage) have not been published. This report describes the development of 21 ANN c-QSAR models (QSAR-21) for assessing eye corrosion potential of chemicals using a large and diverse CFSAN data set of 504 chemicals, ADMET Predictor's three sensitivity analyses and ANNE classification functionalities with 20% test set selection from seven different methods. QSAR-21 models were internally and externally validated and exhibited high predictive performance: average statistics for the training, verification, and external test sets of these models were 96/96/94% sensitivity and 91/91/90% specificity. Copyright © 2014 Elsevier Inc. All rights reserved.

Enhancement of Biomass and Lipid Productivities of Water Surface-Floating Microalgae by Chemical Mutagenesis

PubMed Central

Nojima, Daisuke; Ishizuka, Yuki; Muto, Masaki; Ujiro, Asuka; Kodama, Fumito; Yoshino, Tomoko; Maeda, Yoshiaki; Matsunaga, Tadashi; Tanaka, Tsuyoshi

2017-01-01

Water surface-floating microalgae have great potential for biofuel applications due to the ease of the harvesting process, which is one of the most problematic steps in conventional microalgal biofuel production. We have collected promising water surface-floating microalgae and characterized their capacity for biomass and lipid production. In this study, we performed chemical mutagenesis of two water surface-floating microalgae to elevate productivity. Floating microalgal strains AVFF007 and FFG039 (tentatively identified as Botryosphaerella sp. and Chlorococcum sp., respectively) were exposed to ethyl methane sulfonate (EMS) or 1-methyl-3-nitro-1-nitrosoguanidine (MNNG), and pale green mutants (PMs) were obtained. The most promising FFG039 PM formed robust biofilms on the surface of the culture medium, similar to those formed by wild type strains, and it exhibited 1.7-fold and 1.9-fold higher biomass and lipid productivities than those of the wild type. This study indicates that the chemical mutation strategy improves the lipid productivity of water surface-floating microalgae without inhibiting biofilm formation and floating ability. PMID:28555001

Enhancement of Biomass and Lipid Productivities of Water Surface-Floating Microalgae by Chemical Mutagenesis.

PubMed

Nojima, Daisuke; Ishizuka, Yuki; Muto, Masaki; Ujiro, Asuka; Kodama, Fumito; Yoshino, Tomoko; Maeda, Yoshiaki; Matsunaga, Tadashi; Tanaka, Tsuyoshi

2017-05-27

Water surface-floating microalgae have great potential for biofuel applications due to the ease of the harvesting process, which is one of the most problematic steps in conventional microalgal biofuel production. We have collected promising water surface-floating microalgae and characterized their capacity for biomass and lipid production. In this study, we performed chemical mutagenesis of two water surface-floating microalgae to elevate productivity. Floating microalgal strains AVFF007 and FFG039 (tentatively identified as Botryosphaerella sp. and Chlorococcum sp., respectively) were exposed to ethyl methane sulfonate (EMS) or 1-methyl-3-nitro-1-nitrosoguanidine (MNNG), and pale green mutants (PMs) were obtained. The most promising FFG039 PM formed robust biofilms on the surface of the culture medium, similar to those formed by wild type strains, and it exhibited 1.7-fold and 1.9-fold higher biomass and lipid productivities than those of the wild type. This study indicates that the chemical mutation strategy improves the lipid productivity of water surface-floating microalgae without inhibiting biofilm formation and floating ability.

Impact of nuclear transmutations on the primary damage production: The example of Ni based steels

NASA Astrophysics Data System (ADS)

Luneville, Laurence; Sublet, Jean Christphe; Simeone, David

2018-07-01

The recent nuclear evaluations describe more accurately the elastic and inelastic neutron-atoms interactions and allow calculating more realistically primary damage induced by nuclear reactions. Even if these calculations do not take into account relaxation processes occurring at the end of the displacement cascade (calculations are performed within the Binary Collision Approximation), they can accurately describe primary and recoil spectra in different reactors opening the door for simulating aging of nuclear materials with Ion Beam facilities. Since neutrons are only sensitive to isotopes, these spectra must be calculated weighting isotope spectra by the isotopic composition of materials under investigation. To highlight such a point, primary damage are calculated in pure Ni exhibiting a meta-stable isotope produced under neutron flux by inelastic neutron-isotope processes. These calculations clearly point out that the instantaneous primary damage production, the displacement per atom rate (dpa/s), responsible for the micro-structure evolution, strongly depends on the 59N i isotopic fractions closely related to the inelastic neutron isotope processes. Since the isotopic composition of the meta-stable isotope vanishes for large fluences, the long term impact of this isotope does not largely modify drastically the total dpa number in Ni based steels materials irradiate in nuclear plants.

Soursop (Annona muricata) vinegar production and its chemical compositions

NASA Astrophysics Data System (ADS)

Ho, Chin Wai; Lazim, Azwan Mat; Fazry, Shazrul; Zaki, Umi Kalsum Hj Hussain; Lim, Seng Joe

2016-11-01

Vinegar is a liquid product that undergoes double fermentations, which are alcoholic and acetous fermentation. Sugar source was converted to ethanol in alcoholic fermentation, meanwhile ethanol was oxidised to acetic acid during acetous fermentation. Soursop (Annona muricata) was the starting material in this study, as it is easily available in Malaysia. Its highly aromatic, juicy and distinctive flavours enables the production of high quality vinegar. The objective of this research is to produce good quality soursop vinegar as an innovative method to preserve and utilise the soursop fruit in Malaysia and to determine its chemical compositions. It was found that the sugar content reduces over time, and it is inversely proportional to the ethanol concentration, due to the production of ethanol from sugar. Acetic acid was also found to increase with increasing fermentation time. pH showed no significant difference (p>0.05) in the reduction of sugar and the production of ethanol. However, significantly higher (p<0.05) production of acetic acid was observed at pH 5.0 and 5.5, compared to that at pH 4.5. There were no significant differences (p > 0.05) in Vitamin C contents in all soursop vinegar samples produced using different treatments.

Chemical diversity of microbial volatiles and their potential for plant growth and productivity

PubMed Central

Kanchiswamy, Chidananda Nagamangala; Malnoy, Mickael; Maffei, Massimo E.

2015-01-01

Microbial volatile organic compounds (MVOCs) are produced by a wide array of microorganisms ranging from bacteria to fungi. A growing body of evidence indicates that MVOCs are ecofriendly and can be exploited as a cost-effective sustainable strategy for use in agricultural practice as agents that enhance plant growth, productivity, and disease resistance. As naturally occurring chemicals, MVOCs have potential as possible alternatives to harmful pesticides, fungicides, and bactericides as well as genetic modification. Recent studies performed under open field conditions demonstrate that efficiently adopting MVOCs may contribute to sustainable crop protection and production. We review here the chemical diversity of MVOCs by describing microbial–plants and microbial–microbial interactions. Furthermore, we discuss MVOCs role in inducing phenotypic plant responses and their potential physiological effects on crops. Finally, we analyze potential and actual limitations for MVOC use and deployment in field conditions as a sustainable strategy for improving productivity and reducing pesticide use. PMID:25821453

A comparative study on the raft chemical properties of various alginate antacid raft-forming products.

PubMed

Dettmar, Peter W; Gil-Gonzalez, Diana; Fisher, Jeanine; Flint, Lucy; Rainforth, Daniel; Moreno-Herrera, Antonio; Potts, Mark

2018-01-01

Research to measure the chemical characterization of alginate rafts for good raft performance and ascertain how formulation can affect chemical parameters. A selection of alginate formulations was investigated all claiming to be proficient raft formers with significance between products established and ranked. Procedures were selected which demonstrated the chemical characterization allowing rafts to effectively impede the reflux into the esophagus or in severe cases to be refluxed preferentially into the esophagus and exert a demulcent effect, with focus of current research on methods which complement previous studies centered on physical properties. The alginate content was analyzed by a newly developed HPLC method. Methods were used to determine the neutralization profile and the acid neutralization within the raft determined along with how raft structure affects neutralization. Alginate content of Gaviscon Double Action (GDA) within the raft was significantly superior (p < .0001) to all competitor products. The two products with the highest raft acid neutralization capacity were GDA and Rennie Duo, the latter product not being a raft former. Raft structure was key and GDA had the right level of porosity to allow for longer duration of neutralization. Alginate formulations require three chemical reactions to take place simultaneously: transformation to alginic acid, sodium carbonate reacting to form carbon dioxide, calcium releasing free calcium ions to bind with alginic acid providing strength to raft formation. GDA was significantly superior (p <.0001) to all other comparators.

15 CFR 712.5 - Annual declaration requirements for facilities engaged in the production of Schedule 1 chemicals...

Code of Federal Regulations, 2010 CFR

2010-01-01

...) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 1 CHEMICALS § 712.5 Annual declaration requirements for facilities engaged in... facilities engaged in the production of Schedule 1 chemicals for purposes not prohibited by the CWC. 712.5...

Detection of DNA damage by using hairpin molecular beacon probes and graphene oxide.

PubMed

Zhou, Jie; Lu, Qian; Tong, Ying; Wei, Wei; Liu, Songqin

2012-09-15

A hairpin molecular beacon tagged with carboxyfluorescein in combination with graphene oxide as a quencher reagent was used to detect the DNA damage by chemical reagents. The fluorescence of molecular beacon was quenched sharply by graphene oxide; while in the presence of its complementary DNA the quenching efficiency decreased because their hybridization prevented the strong adsorbability of molecular beacon on graphene oxide. If the complementary DNA was damaged by a chemical reagent and could not form intact duplex structure with molecular beacon, more molecular beacon would adsorb on graphene oxide increasing the quenching efficiency. Thus, damaged DNA could be detected based on different quenching efficiencies afforded by damaged and intact complementary DNA. The damage effects of chlorpyrifos-methyl and three metabolites of styrene such as mandelieaeids, phenylglyoxylieaeids and epoxystyrene on DNA were studied as models. The method for detection of DNA damage was reliable, rapid and simple compared to the biological methods. Copyright © 2012 Elsevier B.V. All rights reserved.

A Chemical Monitoring Program of the Explosion Products in Underwater Explosion Tests

DTIC Science & Technology

1975-04-04

CLASSIFICATION QF THIS PAGE- (When Date Entered) UNCLASSIFIED tL,URJTY CLASSIFICATION OF THIS PAGE(Then Data Entered) 20.and determination of various explosion...to institute a chemical monitoring program of the explosion products in underwater explosion tests, to determine monitoring parameters, and to...27 3.2.3 Samplers 28 3.2.4 Storage of Sediment Samples 32 IV. DETERMINATION OF EXPLOSION PRODUCTS 32 4.1 DESIGN OF MEASUREMENT SYSTEM 32 4.1.1

Transgenic Hybrid Poplar for Sustainable and Scalable Production of the Commodity/Specialty Chemical, 2-Phenylethanol

PubMed Central

Costa, Michael A.; Marques, Joaquim V.; Dalisay, Doralyn S.; Herman, Barrington; Bedgar, Diana L.; Davin, Laurence B.; Lewis, Norman G.

2013-01-01

Fast growing hybrid poplar offers the means for sustainable production of specialty and commodity chemicals, in addition to rapid biomass production for lignocellulosic deconstruction. Herein we describe transformation of fast-growing transgenic hybrid poplar lines to produce 2-phenylethanol, this being an important fragrance, flavor, aroma, and commodity chemical. It is also readily converted into styrene or ethyl benzene, the latter being an important commodity aviation fuel component. Introducing this biochemical pathway into hybrid poplars marks the beginnings of developing a platform for a sustainable chemical delivery system to afford this and other valuable specialty/commodity chemicals at the scale and cost needed. These modified plant lines mainly sequester 2-phenylethanol via carbohydrate and other covalently linked derivatives, thereby providing an additional advantage of effective storage until needed. The future potential of this technology is discussed. MALDI metabolite tissue imaging also established localization of these metabolites in the leaf vasculature. PMID:24386157

HIV-1 Tat protein induces DNA damage in human peripheral blood B-lymphocytes via mitochondrial ROS production.

PubMed

El-Amine, Rawan; Germini, Diego; Zakharova, Vlada V; Tsfasman, Tatyana; Sheval, Eugene V; Louzada, Ruy A N; Dupuy, Corinne; Bilhou-Nabera, Chrystèle; Hamade, Aline; Najjar, Fadia; Oksenhendler, Eric; Lipinski, Marс; Chernyak, Boris V; Vassetzky, Yegor S

2018-05-01

Human immunodeficiency virus (HIV) infection is associated with B-cell malignancies in patients though HIV-1 is not able to infect B-cells. The rate of B-cell lymphomas in HIV-infected individuals remains high even under the combined antiretroviral therapy (cART) that reconstitutes the immune function. Thus, the contribution of HIV-1 to B-cell oncogenesis remains enigmatic. HIV-1 induces oxidative stress and DNA damage in infected cells via multiple mechanisms, including viral Tat protein. We have detected elevated levels of reactive oxygen species (ROS) and DNA damage in B-cells of HIV-infected individuals. As Tat is present in blood of infected individuals and is able to transduce cells, we hypothesized that it could induce oxidative DNA damage in B-cells promoting genetic instability and malignant transformation. Indeed, incubation of B-cells isolated from healthy donors with purified Tat protein led to oxidative stress, a decrease in the glutathione (GSH) levels, DNA damage and appearance of chromosomal aberrations. The effects of Tat relied on its transcriptional activity and were mediated by NF-κB activation. Tat stimulated oxidative stress in B-cells mostly via mitochondrial ROS production which depended on the reverse electron flow in Complex I of respiratory chain. We propose that Tat-induced oxidative stress, DNA damage and chromosomal aberrations are novel oncogenic factors favoring B-cell lymphomas in HIV-1 infected individuals. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

16 CFR 301.22 - Disclosure of damaged furs.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Disclosure of damaged furs. 301.22 Section 301.22 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULES... decrease the normal life and durability of such product. (b) When damaged furs are used in a fur product...

Novel Strategies for the Production of Fuels, Lubricants, and Chemicals from Biomass.

PubMed

Shylesh, Sankaranarayanapillai; Gokhale, Amit A; Ho, Christopher R; Bell, Alexis T

2017-10-17

Growing concern with the environmental impact of CO 2 emissions produced by combustion of fuels derived from fossil-based carbon resources has stimulated the search for renewable sources of carbon. Much of this focus has been on the development of methods for producing transportation fuels, the major source of CO 2 emissions today, and to a lesser extent on the production of lubricants and chemicals. First-generation biofuels such as bioethanol, produced by the fermentation of sugar cane- or corn-based sugars, and biodiesel, produced by the transesterification reaction of triglycerides with alcohols to form a mixture of long-chain fatty esters, can be blended with traditional fuels in limited amounts and also arise in food versus fuel debates. Producing molecules that can be drop-in solutions for fossil-derived products used in the transportation sector allows for efficient use of the existing infrastructure and is therefore particularly interesting. In this context, the most viable source of renewable carbon is abundantly available lignocellulosic biomass, a complex mixture of lignin, hemicellulose, and cellulose. Conversion of the carbohydrate portion of biomass (hemicellulose and cellulose) to fuels requires considerable chemical restructuring of the component sugars in order to achieve the energy density and combustion properties required for transportation fuels-gasoline, diesel, and jet. A different set of constraints must be met for the conversion of biomass-sourced sugars to lubricants and chemicals. This Account describes strategies developed by us to utilize aldehydes, ketones, alcohols, furfurals, and carboxylic acids derived from C 5 and C 6 sugars, acetone-butanol-ethanol (ABE) fermentation mixtures, and various biomass-derived carboxylic acids and fatty acids to produce fuels, lubricants, and chemicals. Oxygen removal from these synthons is achieved by dehydration, decarboxylation, hydrogenolysis, and hydrodeoxygenation, whereas reactions such as

Steroid profiling in H295R cells to identify chemicals potentially disrupting the production of adrenal steroids.

PubMed

Strajhar, Petra; Tonoli, David; Jeanneret, Fabienne; Imhof, Raphaella M; Malagnino, Vanessa; Patt, Melanie; Kratschmar, Denise V; Boccard, Julien; Rudaz, Serge; Odermatt, Alex

2017-04-15

The validated OECD test guideline 456 based on human adrenal H295R cells promotes measurement of testosterone and estradiol production as read-out to identify potential endocrine disrupting chemicals. This study aimed to establish optimal conditions for using H295R cells to detect chemicals interfering with the production of key adrenal steroids. H295R cells' supernatants were characterized by liquid chromatography-mass spectrometry (LC-MS)-based steroid profiling, and the influence of experimental conditions including time and serum content was assessed. Steroid profiles were determined before and after incubation with reference compounds and chemicals to be tested for potential disruption of adrenal steroidogenesis. The H295R cells cultivated according to the OECD test guideline produced progestins, glucocorticoids, mineralocorticoids and adrenal androgens but only very low amounts of testosterone. However, testosterone contained in Nu-serum was metabolized during the 48h incubation. Thus, inclusion of positive and negative controls and a steroid profile of the complete medium prior to the experiment (t=0h) was necessary to characterize H295R cells' steroid production and indicate alterations caused by exposure to chemicals. Among the tested chemicals, octyl methoxycinnamate and acetyl tributylcitrate resembled the corticosteroid induction pattern of the positive control torcetrapib. Gene expression analysis revealed that octyl methoxycinnamate and acetyl tributylcitrate enhanced CYP11B2 expression, although less pronounced than torcetrapib. Further experiments need to assess the toxicological relevance of octyl methoxycinnamate- and acetyl tributylcitrate-induced corticosteroid production. In conclusion, the extended profiling and appropriate controls allow detecting chemicals that act on steroidogenesis and provide initial mechanistic evidence for prioritizing chemicals for further investigations. Copyright © 2017 Elsevier B.V. All rights reserved.

Mechanisms of DNA damage, repair and mutagenesis

PubMed Central

Chatterjee, Nimrat; Walker, Graham C.

2017-01-01

Living organisms are continuously exposed to a myriad of DNA damaging agents that can impact health and modulate disease-states. However, robust DNA repair and damage-bypass mechanisms faithfully protect the DNA by either removing or tolerating the damage to ensure an overall survival. Deviations in this fine-tuning are known to destabilize cellular metabolic homeostasis, as exemplified in diverse cancers where disruption or deregulation of DNA repair pathways results in genome instability. Because routinely used biological, physical and chemical agents impact human health, testing their genotoxicity and regulating their use have become important. In this introductory review, we will delineate mechanisms of DNA damage and the counteracting repair/tolerance pathways to provide insights into the molecular basis of genotoxicity in cells that lays the foundation for subsequent articles in this issue. PMID:28485537

Tolerance engineering in bacteria for the production of advanced biofuels and chemicals.

PubMed

Mukhopadhyay, Aindrila

2015-08-01

During microbial production of solvent-like compounds, such as advanced biofuels and bulk chemicals, accumulation of the final product can negatively impact the cultivation of the host microbe and limit the production levels. Consequently, improving solvent tolerance is becoming an essential aspect of engineering microbial production strains. Mechanisms ranging from chaperones to transcriptional factors have been used to obtain solvent-tolerant strains. However, alleviating growth inhibition does not invariably result in increased production. Transporters specifically have emerged as a powerful category of proteins that bestow tolerance and often improve production but are difficult targets for cellular expression. Here we review strain engineering, primarily as it pertains to bacterial solvent tolerance, and the benefits and challenges associated with the expression of membrane-localized transporters in improving solvent tolerance and production. Copyright © 2015 Elsevier Ltd. All rights reserved.

Teachers' Misconceptions about the Effects of Addition of More Reactants or Products on Chemical Equilibrium

ERIC Educational Resources Information Center

Cheung, Derek; Ma, Hong-jia; Yang, Jie

2009-01-01

The importance of research on misconceptions about chemical equilibrium is well recognized by educators, but in the past, researchers' interest has centered on student misconceptions and has neglected teacher misconceptions. Focusing on the effects of adding more reactants or products on chemical equilibrium, this article discusses the various…

Bisphenol A Promotes Cell Survival Following Oxidative DNA Damage in Mouse Fibroblasts

PubMed Central

Gassman, Natalie R.; Coskun, Erdem; Stefanick, Donna F.; Horton, Julie K.; Jaruga, Pawel; Dizdaroglu, Miral; Wilson, Samuel H.

2015-01-01

Bisphenol A (BPA) is a biologically active industrial chemical used in production of consumer products. BPA has become a target of intense public scrutiny following concerns about its association with human diseases such as obesity, diabetes, reproductive disorders, and cancer. Recent studies link BPA with the generation of reactive oxygen species, and base excision repair (BER) is responsible for removing oxidatively induced DNA lesions. Yet, the relationship between BPA and BER has yet to be examined. Further, the ubiquitous nature of BPA allows continuous exposure of the human genome concurrent with the normal endogenous and exogenous insults to the genome, and this co-exposure may impact the DNA damage response and repair. To determine the effect of BPA exposure on base excision repair of oxidatively induced DNA damage, cells compromised in double-strand break repair were treated with BPA alone or co-exposed with either potassium bromate (KBrO3) or laser irradiation as oxidative damaging agents. In experiments with KBrO3, co-treatment with BPA partially reversed the KBrO3-induced cytotoxicity observed in these cells, and this was coincident with an increase in guanine base lesions in genomic DNA. The improvement in cell survival and the increase in oxidatively induced DNA base lesions were reminiscent of previous results with alkyl adenine DNA glycosylase-deficient cells, suggesting that BPA may prevent initiation of repair of oxidized base lesions. With laser irradiation-induced DNA damage, treatment with BPA suppressed DNA repair as revealed by several indicators. These results are consistent with the hypothesis that BPA can induce a suppression of oxidized base lesion DNA repair by the base excision repair pathway. PMID:25693136

Alkylation Damage by Lipid Electrophiles Targets Functional Protein Systems*

PubMed Central

Codreanu, Simona G.; Ullery, Jody C.; Zhu, Jing; Tallman, Keri A.; Beavers, William N.; Porter, Ned A.; Marnett, Lawrence J.; Zhang, Bing; Liebler, Daniel C.

2014-01-01

Protein alkylation by reactive electrophiles contributes to chemical toxicities and oxidative stress, but the functional impact of alkylation damage across proteomes is poorly understood. We used Click chemistry and shotgun proteomics to profile the accumulation of proteome damage in human cells treated with lipid electrophile probes. Protein target profiles revealed three damage susceptibility classes, as well as proteins that were highly resistant to alkylation. Damage occurred selectively across functional protein interaction networks, with the most highly alkylation-susceptible proteins mapping to networks involved in cytoskeletal regulation. Proteins with lower damage susceptibility mapped to networks involved in protein synthesis and turnover and were alkylated only at electrophile concentrations that caused significant toxicity. Hierarchical susceptibility of proteome systems to alkylation may allow cells to survive sublethal damage while protecting critical cell functions. PMID:24429493

Chemically-bonded brick production based on burned clay by means of semidry pressing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voroshilov, Ivan, E-mail: Nixon.06@mail.ru; Endzhievskaya, Irina, E-mail: icaend@mail.ru; Vasilovskaya, Nina, E-mail: icaend@mail.ru

We presented a study on the possibility of using the burnt rocks of the Krasnoyarsk Territory for production of chemically-bonded materials in the form of bricks which are so widely used in multistory housing and private house construction. The radiographic analysis of the composition of burnt rock was conducted and a modifier to adjust the composition uniformity was identified. The mixing moisture content was identified and optimal amount at 13-15% was determined. The method of semidry pressing has been chosen. The process of obtaining moldings has been theoretically proved; the advantages of chemically-bonded wall materials compared to ceramic brick weremore » shown. The production of efficient artificial stone based on material burnt rocks, which is comparable with conventionally effective ceramic materials or effective with cell tile was proved, the density of the burned clay-based cell tile makes up to 1630-1785 kg \\ m{sup 3}, with compressive strength of 13.6-20.0 MPa depending on the compression ratio and cement consumption, frost resistance index is F50, and the thermal conductivity in the masonry is λ = 0,459-0,546 W \\ m {sup *} °C. The clear geometric dimensions of pressed products allow the use of the chemically-bonded brick based on burnt clay as a facing brick.« less

Mass production of chemicals from biomass-derived oil by directly atmospheric distillation coupled with co-pyrolysis

NASA Astrophysics Data System (ADS)

Zhang, Xue-Song; Yang, Guang-Xi; Jiang, Hong; Liu, Wu-Jun; Ding, Hong-Sheng

2013-01-01

Production of renewable commodity chemicals from bio-oil derived from fast pyrolysis of biomass has received considerable interests, but hindered by the presence of innumerable components in bio-oil. In present work, we proposed and experimentally demonstrated an innovative approach combining atmospheric distillation of bio-oil with co-pyrolysis for mass production of renewable chemicals from biomass, in which no waste was produced. It was estimated that 51.86 wt.% of distillate just containing dozens of separable organic components could be recovered using this approach. Ten protogenetic and three epigenetic compounds in distillate were qualitatively identified by gas chromatography/mass spectrometry and quantified by gas chromatography. Among them, the recovery efficiencies of acetic acid, propanoic acid, and furfural were all higher than 80 wt.%. Formation pathways of the distillate components in this process were explored. This work opens up a fascinating prospect for mass production of chemical feedstock from waste biomass.

Mapping Students' Conceptual Modes When Thinking about Chemical Reactions Used to Make a Desired Product

ERIC Educational Resources Information Center

Weinrich, M. L.; Talanquer, V.

2015-01-01

The central goal of this qualitative research study was to uncover major implicit assumptions that students with different levels of training in the discipline apply when thinking and making decisions about chemical reactions used to make a desired product. In particular, we elicited different ways of conceptualizing why chemical reactions happen…

The Changing Landscape of Hydrocarbon Feedstocks for Chemical Production: Implications for Catalysis: Proceedings of a Workshop

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bell, Alexis T.; Alger, Monty M.; Flytzani-Stephanopoulos, Maria

A decade ago, the U.S. chemical industry was in decline. Of the more than 40 chemical manufacturing plants being built worldwide in the mid-2000s with more than $1 billion in capitalization, none were under construction in the United States. Today, as a result of abundant domestic supplies of affordable natural gas and natural gas liquids resulting from the dramatic rise in shale gas production, the U.S. chemical industry has gone from the world’s highest-cost producer in 2005 to among the lowest-cost producers today. The low cost and increased supply of natural gas and natural gas liquids provides an opportunity tomore » discover and develop new catalysts and processes to enable the direct conversion of natural gas and natural gas liquids into value-added chemicals with a lower carbon footprint. The economic implications of developing advanced technologies to utilize and process natural gas and natural gas liquids for chemical production could be significant, as commodity, intermediate, and fine chemicals represent a higher-economic-value use of shale gas compared with its use as a fuel. To better understand the opportunities for catalysis research in an era of shifting feedstocks for chemical production and to identify the gaps in the current research portfolio, the National Academies of Sciences, Engineering, and Medicine conducted an interactive, multidisciplinary workshop in March 2016. The goal of this workshop was to identify advances in catalysis that can enable the United States to fully realize the potential of the shale gas revolution for the U.S. chemical industry and, as a result, to help target the efforts of U.S. researchers and funding agencies on those areas of science and technology development that are most critical to achieving these advances. This publication summarizes the presentations and discussions from the workshop.« less

Reliability Evaluation and Improvement Approach of Chemical Production Man - Machine - Environment System

NASA Astrophysics Data System (ADS)

Miao, Yongchun; Kang, Rongxue; Chen, Xuefeng

2017-12-01

In recent years, with the gradual extension of reliability research, the study of production system reliability has become the hot topic in various industries. Man-machine-environment system is a complex system composed of human factors, machinery equipment and environment. The reliability of individual factor must be analyzed in order to gradually transit to the research of three-factor reliability. Meanwhile, the dynamic relationship among man-machine-environment should be considered to establish an effective blurry evaluation mechanism to truly and effectively analyze the reliability of such systems. In this paper, based on the system engineering, fuzzy theory, reliability theory, human error, environmental impact and machinery equipment failure theory, the reliabilities of human factor, machinery equipment and environment of some chemical production system were studied by the method of fuzzy evaluation. At last, the reliability of man-machine-environment system was calculated to obtain the weighted result, which indicated that the reliability value of this chemical production system was 86.29. Through the given evaluation domain it can be seen that the reliability of man-machine-environment integrated system is in a good status, and the effective measures for further improvement were proposed according to the fuzzy calculation results.

Reduced hazard chemicals for solid rocket motor production

NASA Technical Reports Server (NTRS)

Caddy, Larry A.; Bowman, Ross; Richards, Rex A.

1995-01-01

During the last three years. the NASA/Thiokol/industry team has developed and started implementation of an environmentally sound manufacturing plan for the continued production of solid rocket motors. NASA Marshall Space Flight Center (MSFC) and Thiokol Corporation have worked with other industry representatives and the U.S. Environmental Protection Agency (EPA) to prepare a comprehensive plan to eliminate all ozone depleting chemicals from manufacturing processes and reduce the use of other hazardous materials used to produce the space shuttle reusable solid rocket motors. The team used a classical approach for problem-solving combined with a creative synthesis of new approaches to attack this challenge.

Understanding radiation damage on sub-cellular scale using RADAMOL simulation tool

NASA Astrophysics Data System (ADS)

Štěpán, Václav; Davídková, Marie

2016-11-01

We present an overview of the biophysical model RADAMOL developed as a Monte Carlo simulation tool for physical, physico-chemical and chemical stages of ionizing radiation action. Direct and indirect radiation damage by 10 keV electrons, and protons and alpha particles with energies from 1 MeV up to 30 MeV to a free DNA oligomer or DNA in the complex with lac repressor protein is analyzed. The role of radiation type and energy, oxygen concentration and DNA interaction with proteins on yields and distributions of primary biomolecular damage is demonstrated and discussed.

Nondestructive Damage Characterization of Alumina Ceramics

DTIC Science & Technology

2009-07-01

damage. 15. SUBJECT TERMS impact testing, impact damage, ultrasound, digital radiography 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF...No. A748883; 3Tex Fiber Products: Cary, NC, 2001. 7. Chacon -Nava, J. G.; Stott, F. H.; de la Torre, S. D.; Martinez-Villafane, A. Erosion of

Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO 2 Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kathe, Mandar; Xu, Dikai; Hsieh, Tien-Lin

2014-12-31

This document is the final report for the project titled “Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO 2 Capture” under award number FE0012136 for the performance period 10/01/2013 to 12/31/2014.This project investigates the novel Ohio State chemical looping gasification technology for high efficiency, cost efficiency coal gasification for IGCC and methanol production application. The project developed an optimized oxygen carrier composition, demonstrated the feasibility of the concept and completed cold-flow model studies. WorleyParsons completed a techno-economic analysis which showed that for a coal only feed with carbon capture, the OSU CLG technology reduced the methanol requiredmore » selling price by 21%, lowered the capital costs by 28%, increased coal consumption efficiency by 14%. Further, using the Ohio State Chemical Looping Gasification technology resulted in a methanol required selling price which was lower than the reference non-capture case.« less

Nondestructive analysis of alkali-silica reaction damage in concrete slabs using shear waves

NASA Astrophysics Data System (ADS)

Khazanovich, Lev; Freeseman, Katelyn; Salles, Lucio; Clayton, Dwight

2018-04-01

Alkali-silica reaction (ASR) is the chemical reaction that occurs in concrete. It is caused by the interaction of alkalis in Portland cement and silica in aggregates and results in microcracks within the material. This type of damage has been the focus of nondestructive evaluation efforts in recent history, but no work was done on in-situ structures or large-scale samples. To address these limitations, an ultrasonic linear array device, MIRA, was utilized for this research. An experimental investigation was performed on four slabs with various levels of alkali-silica reaction at the Electric Power Research Institute (EPRI) [1]. One-period impulses with a target of 50kHz center frequency were selected in this study. We propose the use of the Hilbert Transform Indicator (HTI) for quantification of ASR damage [2]. A higher HTI value would be indicative of damaged concrete, while a low value represents sound concrete. In general, values below 90 are regarded as an indicator of sound concrete while values above 100 indicate the presence of damage [3]. The ability of the HTI values to distinguish between areas of damaged concrete was evident via the production of color intensity maps. The maps show that the control specimen, was in good condition, while other slabs exhibited higher levels of damage as indicated by the HTI values. It should be noted that extreme damage conditions were not present in any of the slabs. Evaluation of migration-based reconstructions can give a qualitative characterization of large scale or excessive subsurface damage. However, for detection of stochastic damage mechanisms such as freeze-thaw damage, evaluation of the individual time-history data can provide additional information. A comparison of the spatially diverse measurements on several concrete slabs with varying freeze-thaw damage levels is given in this study. Signal characterization scans of different levels of freeze-thaw damage at various transducer spacing is investigated. The

Chemical Reaction and Flow Modeling in Fullerene and Nanotube Production

NASA Technical Reports Server (NTRS)

Scott, Carl D.; Farhat, Samir; Greendyke, Robert B.

2004-01-01

The development of processes to produce fullerenes and carbon nanotubes has largely been empirical. Fullerenes were first discovered in the soot produced by laser ablation of graphite [1]and then in the soot of electric arc evaporated carbon. Techniques and conditions for producing larger and larger quantities of fullerenes depended mainly on trial and error empirical variations of these processes, with attempts to scale them up by using larger electrodes and targets and higher power. Various concepts of how fullerenes and carbon nanotubes were formed were put forth, but very little was done based on chemical kinetics of the reactions. This was mainly due to the complex mixture of species and complex nature of conditions in the reactors. Temperatures in the reactors varied from several thousand degrees Kelvin down to near room temperature. There are hundreds of species possible, ranging from atomic carbon to large clusters of carbonaceous soot, and metallic catalyst atoms to metal clusters, to complexes of metals and carbon. Most of the chemical kinetics of the reactions and the thermodynamic properties of clusters and complexes have only been approximated. In addition, flow conditions in the reactors are transient or unsteady, and three dimensional, with steep spatial gradients of temperature and species concentrations. All these factors make computational simulations of reactors very complex and challenging. This article addresses the development of the chemical reaction involved in fullerene production and extends this to production of carbon nanotubes by the laser ablation/oven process and by the electric arc evaporation process. In addition, the high-pressure carbon monoxide (HiPco) process is discussed. The article is in several parts. The first one addresses the thermochemical aspects of modeling; and considers the development of chemical rate equations, estimates of reaction rates, and thermodynamic properties where they are available. The second part

MUTAGENICITY IN SALMONELLA AND DNA DAMAGE IN THE CHO/COMET ASSAY INDUCED BY NITROHALOMETHANES, A NOVEL CLASS OF DRINKING WATER DISINFECTION BY-PRODUCTS

EPA Science Inventory

Mutagenicity in Salmonella and DNA Damage in the CHO/Comet Assay Induced by Nitrohalomethanes, a Novel Class of Drinking Water Disinfection By-Products.

Halomethanes are a class of drinking water disinfection by-products (DBPs) whose genotoxicity has been studied extensi...

Chemical characterization, energy values, protein and carbohydrate fractions, degradation kinetics of frost damaged wheat (with severely overall weight loss) in ruminants.

PubMed

Yu, Peiqiang; Racz, Vern

2009-04-01

In Canada, frost damage can result in millions of tonnes of wheat that is not suitable for human consumption (such wheat is referred to as 'frozen') each year. There is a need to systematically evaluate the nutritive value of frozen wheat for ruminants. So far, little research has been conducted to determine the magnitude of the differences in nutritive value between frozen and normal wheat. The objectives of this study were to compare frozen wheat and normal wheat (AC Barrie) in terms of (i) chemical characteristics; (ii) protein and carbohydrate fractions; (iii) energy value; and (iv) rumen degradation kinetics. The results showed that the overall yield losses of the frozen wheat were around 24%. The frozen wheat was significantly lower (P < 0.05) in starch (47 vs. 62%DM), non-structural carbohydrates (60 vs. 70%DM), and non-protein N (63 vs. 93%SCP); and higher (P < 0.05) in crude fat (3 vs. 2%DM), acid (6 vs. 2%DM), neutral detergent fiber (22 vs. 10%DM), lignin (2 vs. 1%DM), acid (3 vs. 1%CP) and neutral detergent insoluble CP (19 vs. 14%CP). The frozen wheat was also lower in (P < 0.05) energy (TDN, DE(3X), ME(3X,) NEL(3X), DE(4X), ME(4X,) NEL(4X) for dairy; ME, NE(m), and NE(g) beef cattle). After partitioning of protein and carbohydrate (CHO) subfractions, the results showed that the frozen wheat was lower (P < 0.05) in the intermediately degradable CP (PB2: 47 vs. 59%CP); and higher in rapidly degradable CP (PB1: 12 vs. 2%CP) and unavailable CP (PC: 3 vs. 1%CP). The frozen wheat was also lower (P < 0.05) in intermediately degradable CHO (CB1: 60 vs. 77%CHO); and higher (P < 0.05) in slowly degradable CHO (CB2: 20 vs. 8%CHO) and unavailable CHO (CC: 5 vs. 2%CHO). The in situ results showed that the frozen wheat had different patterns in rumen degradation kinetics of protein and starch. The extent of the changes varied according to the specific nutrient examined. In conclusion, the frozen wheat differed in chemical characteristics, TDN and energy values

Chemical warfare agents.

PubMed

Kuca, Kamil; Pohanka, Miroslav

2010-01-01

Chemical warfare agents are compounds of different chemical structures. Simple molecules such as chlorine as well as complex structures such as ricin belong to this group. Nerve agents, vesicants, incapacitating agents, blood agents, lung-damaging agents, riot-control agents and several toxins are among chemical warfare agents. Although the use of these compounds is strictly prohibited, the possible misuse by terrorist groups is a reality nowadays. Owing to this fact, knowledge of the basic properties of these substances is of a high importance. This chapter briefly introduces the separate groups of chemical warfare agents together with their members and the potential therapy that should be applied in case someone is intoxicated by these agents.

DNA damage during glycation of lysine by methylglyoxal: assessment of vitamins in preventing damage.

PubMed

Suji, G; Sivakami, S

2007-11-01

Amino acids react with methylglyoxal to form advanced glycation end products. This reaction is known to produce free radicals. In this study, cleavage to plasmid DNA was induced by the glycation of lysine with methylglyoxal in the presence of iron(III). This system was found to produce superoxide as well as hydroxyl radicals. The abilities of various vitamins to prevent damage to plasmid DNA were evaluated. Pyridoxal-5-phosphate showed maximum protection, while pyridoxamine showed no protection. The protective abilities could be directly correlated to inhibition of production of hydroxyl and superoxide radicals. Pyridoxal-5-phosphate exhibited low radical scavenging ability as evaluated by its TEAC, but showed maximum protection probably by interfering in free radical production. Pyridoxamine did not inhibit free radical production. Thiamine and thiamine pyrophosphate, both showed protective effects albeit to different extents. Tetrahydrofolic acid showed better antioxidant activity than folic acid but was found to damage DNA by itself probably by superoxide generation.

Mass production of chemicals from biomass-derived oil by directly atmospheric distillation coupled with co-pyrolysis

PubMed Central

Zhang, Xue-Song; Yang, Guang-Xi; Jiang, Hong; Liu, Wu-Jun; Ding, Hong-Sheng

2013-01-01

Production of renewable commodity chemicals from bio-oil derived from fast pyrolysis of biomass has received considerable interests, but hindered by the presence of innumerable components in bio-oil. In present work, we proposed and experimentally demonstrated an innovative approach combining atmospheric distillation of bio-oil with co-pyrolysis for mass production of renewable chemicals from biomass, in which no waste was produced. It was estimated that 51.86 wt.% of distillate just containing dozens of separable organic components could be recovered using this approach. Ten protogenetic and three epigenetic compounds in distillate were qualitatively identified by gas chromatography/mass spectrometry and quantified by gas chromatography. Among them, the recovery efficiencies of acetic acid, propanoic acid, and furfural were all higher than 80 wt.%. Formation pathways of the distillate components in this process were explored. This work opens up a fascinating prospect for mass production of chemical feedstock from waste biomass. PMID:23350028

Volatile chemical products emerging as largest petrochemical source of urban organic emissions.

PubMed

McDonald, Brian C; de Gouw, Joost A; Gilman, Jessica B; Jathar, Shantanu H; Akherati, Ali; Cappa, Christopher D; Jimenez, Jose L; Lee-Taylor, Julia; Hayes, Patrick L; McKeen, Stuart A; Cui, Yu Yan; Kim, Si-Wan; Gentner, Drew R; Isaacman-VanWertz, Gabriel; Goldstein, Allen H; Harley, Robert A; Frost, Gregory J; Roberts, James M; Ryerson, Thomas B; Trainer, Michael

2018-02-16

A gap in emission inventories of urban volatile organic compound (VOC) sources, which contribute to regional ozone and aerosol burdens, has increased as transportation emissions in the United States and Europe have declined rapidly. A detailed mass balance demonstrates that the use of volatile chemical products (VCPs)-including pesticides, coatings, printing inks, adhesives, cleaning agents, and personal care products-now constitutes half of fossil fuel VOC emissions in industrialized cities. The high fraction of VCP emissions is consistent with observed urban outdoor and indoor air measurements. We show that human exposure to carbonaceous aerosols of fossil origin is transitioning away from transportation-related sources and toward VCPs. Existing U.S. regulations on VCPs emphasize mitigating ozone and air toxics, but they currently exempt many chemicals that lead to secondary organic aerosols. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Mechanistic-based non-animal assessment of eye toxicity: Inflammatory profile of human keratinocytes cells after exposure to eye damage/irritant agents.

PubMed

da Silva, Artur Christian Garcia; Chialchia, Adrienny Rodrigues; de Ávila, Renato Ivan; Valadares, Marize Campos

2018-06-25

Eye toxicity is a mandatory parameter in human risk and safety evaluation for products including chemicals, pesticides, medicines and cosmetics. Historically, this endpoint has been evaluated using the Draize rabbit eye test, an in vivo model that was never formally validated. Due to advances in scientific knowledge, economic and ethical issues, non-animal methods based on mechanisms of toxicity are being developed and validated for increasing the capability of these models to predict eye toxicity. In this study, the Cytometric Bead Array (CBA) and ELISA assays were used to evaluate the inflammatory cytokine profile produced by HaCaT human keratinocytes after exposure to chemicals with different UN GHS eye toxicity classifications, aiming to stablish a correlation between inflammatory endpoints and eye toxicity (damage/irritation) potential. As a first step, cytotoxic profile of the chemicals, including 3 non-irritants and 10 eye toxicants (GHS Category 1, 2A and 2B), was evaluated after 24 h exposure using MTT assay and Inhibitory Concentration of 20% of cell viability (IC 20 ) was calculated for each chemical. Then, the cells were exposed to these chemicals at IC 20 for 24 h and supernatants and cell lysates were analyzed by CBA assay for quantification of the following cytokines: IL-6, IL-8, IL-10, IL-1β, TNF and IL-12p70. Regarding cytotoxicity evaluation, chemicals showed different cytotoxicity profiles and data demonstrated no correlation with their UN GHS classification. Among the cytokines evaluated, IL-1β production has changed after exposure and such alterations were confirmed by quantification employing ELISA method. The higher intracellular levels of IL-1β were found in GHS Category 1 chemicals, followed by Category 2A and 2B, while non irritants did not induce such increase. Thus, these findings show that IL-1β measurement, using HaCaT model, can be a considerable biomarker to identify chemicals according to their potential in promote eye

NEIL2 Protects against Oxidative DNA Damage Induced by Sidestream Smoke in Human Cells

PubMed Central

Sarker, Altaf H.; Chatterjee, Arpita; Williams, Monique; Lin, Sabrina; Havel, Christopher; Jacob III, Peyton; Boldogh, Istvan; Hazra, Tapas K.; Talbot, Prudence; Hang, Bo

2014-01-01

Secondhand smoke (SHS) is a confirmed lung carcinogen that introduces thousands of toxic chemicals into the lungs. SHS contains chemicals that have been implicated in causing oxidative DNA damage in the airway epithelium. Although DNA repair is considered a key defensive mechanism against various environmental attacks, such as cigarette smoking, the associations of individual repair enzymes with susceptibility to lung cancer are largely unknown. This study investigated the role of NEIL2, a DNA glycosylase excising oxidative base lesions, in human lung cells treated with sidestream smoke (SSS), the main component of SHS. To do so, we generated NEIL2 knockdown cells using siRNA-technology and exposed them to SSS-laden medium. Representative SSS chemical compounds in the medium were analyzed by mass spectrometry. An increased production of reactive oxygen species (ROS) in SSS-exposed cells was detected through the fluorescent detection and the induction of HIF-1α. The long amplicon–quantitative PCR (LA-QPCR) assay detected significant dose-dependent increases of oxidative DNA damage in the HPRT gene of cultured human pulmonary fibroblasts (hPF) and BEAS-2B epithelial cells exposed to SSS for 24 h. These data suggest that SSS exposure increased oxidative stress, which could contribute to SSS-mediated toxicity. siRNA knockdown of NEIL2 in hPF and HEK 293 cells exposed to SSS for 24 h resulted in significantly more oxidative DNA damage in HPRT and POLB than in cells with control siRNA. Taken together, our data strongly suggest that decreased repair of oxidative DNA base lesions due to an impaired NEIL2 expression in non-smokers exposed to SSS would lead to accumulation of mutations in genomic DNA of lung cells over time, thus contributing to the onset of SSS-induced lung cancer. PMID:24595271

Metabolic engineering of Saccharomyces cerevisiae for production of fatty acid-derived biofuels and chemicals.

PubMed

Runguphan, Weerawat; Keasling, Jay D

2014-01-01

As the serious effects of global climate change become apparent and access to fossil fuels becomes more limited, metabolic engineers and synthetic biologists are looking towards greener sources for transportation fuels. In recent years, microbial production of high-energy fuels by economically efficient bioprocesses has emerged as an attractive alternative to the traditional production of transportation fuels. Here, we engineered the budding yeast Saccharomyces cerevisiae to produce fatty acid-derived biofuels and chemicals from simple sugars. Specifically, we overexpressed all three fatty acid biosynthesis genes, namely acetyl-CoA carboxylase (ACC1), fatty acid synthase 1 (FAS1) and fatty acid synthase 2 (FAS2), in S. cerevisiae. When coupled to triacylglycerol (TAG) production, the engineered strain accumulated lipid to more than 17% of its dry cell weight, a four-fold improvement over the control strain. Understanding that TAG cannot be used directly as fuels, we also engineered S. cerevisiae to produce drop-in fuels and chemicals. Altering the terminal "converting enzyme" in the engineered strain led to the production of free fatty acids at a titer of approximately 400 mg/L, fatty alcohols at approximately 100mg/L and fatty acid ethyl esters (biodiesel) at approximately 5 mg/L directly from simple sugars. We envision that our approach will provide a scalable, controllable and economic route to this important class of chemicals. Copyright © 2013 International Metabolic Engineering Society. All rights reserved.

Shelf Life of Anchovy Products (Engraulis Encrasicolus): Evaluation of Sensory, Microbiological and Chemical Properties

PubMed Central

Scarano, Luigi; Mormile, Amalia; Barile, Maria; Palma, Giuseppe; Murru, Nicoletta

2014-01-01

Fishery products have always been an important food in Italy. In the past, increased consumption was mainly due to the good quality of the products, easiness of use and their beneficial effects on health. Recently, owing to the national financial crisis, there has been a decline in the consumption of fish. In fact, in 2013, according to data from ISMEA, the consumption of fresh fish suffered a sharp contraction (-5%). This decline also concerns anchovy (Engraulis encrasicolus). This species, partly because of its low price, is a mainstay of traditional Italian food. The aim of this study was to evaluate sensorial, chemical and microbiological properties of anchovy-based (Engraulis encrasicolus) products during storage at 4 and -20°C. Fresh anchovies, obtained from the wholesale fish market of Pozzuoli (Southern Italy) were cut into small pieces and hand-prepared using bread, eggs, cheese and lemon juice. Samples were analysed after 0, 2, 4, 6 and 8 days of storage at 4°C. An aliquot was quickly frozen and analysed after 34 days at -20°C. Sensory assessment, microbiological (specific spoilage organisms, Listeria spp. and Salmonella spp.) and chemical (histamine, total volatile basic nitrogen, trimethylamine, thiobarbituric acid, pH and aw) analyses were performed. Results showed that the shelf life of anchovy products was less than 5 days for the samples stored at 4°C. At -20°C, all anchovies preparations showed good sensory, microbiological and chemical properties for 34 days. PMID:27800315

Chemical characteristics and enhanced hepatoprotective activities of Maillard reaction products derived from milk protein-sugar system.

PubMed

Oh, Nam Su; Young Lee, Ji; Lee, Hyun Ah; Joung, Jae Yeon; Shin, Yong Kook; Kim, Sae Hun; Kim, Younghoon; Lee, Kwang Won

2016-02-01

The objective of this study was to investigate the characteristics, antioxidative properties, and hepatoprotective effects of Maillard reaction products (MRP) from milk protein reacted with sugars. The MRP were obtained from milk protein, whey protein concentrates and sodium caseinate, using 2 types of sugars, lactose and glucose, by heating the mixture at 55°C for 7d in a sodium phosphate buffer (pH 7.4). Changes in the chemical modification of the milk protein were monitored by measuring the protein-bound carbonyls and PAGE protein profiles. The results showed that the amount of protein-bound carbonyls increased after Maillard reaction (MR). In addition, sodium dodecyl sulfate-PAGE analysis indicated a formation of high-molecular weight complexes through MR. The modification sites induced by MR of milk protein were monitored by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis of tryptic-digested gel spots of MRP. As a result, modification and their localization in AA sequence of MRP was identified. Also, the MRP showed higher antioxidant activities than the intact milk protein, and they reduced intracellular reactive oxygen species production and inhibited the depletion of the reduced glutathione concentrations in the HepG2 cells. In particular, glucose-sodium caseinate MRP showed the highest biological activities among all MRP. Therefore, these results suggest that the MRP from milk protein reacting with sugars possess effective antioxidant activity and have a protective ability against oxidative damage. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Direct Detection and Sequencing of Damaged DNA Bases

PubMed Central

2011-01-01

Products of various forms of DNA damage have been implicated in a variety of important biological processes, such as aging, neurodegenerative diseases, and cancer. Therefore, there exists great interest to develop methods for interrogating damaged DNA in the context of sequencing. Here, we demonstrate that single-molecule, real-time (SMRT®) DNA sequencing can directly detect damaged DNA bases in the DNA template - as a by-product of the sequencing method - through an analysis of the DNA polymerase kinetics that are altered by the presence of a modified base. We demonstrate the sequencing of several DNA templates containing products of DNA damage, including 8-oxoguanine, 8-oxoadenine, O6-methylguanine, 1-methyladenine, O4-methylthymine, 5-hydroxycytosine, 5-hydroxyuracil, 5-hydroxymethyluracil, or thymine dimers, and show that these base modifications can be readily detected with single-modification resolution and DNA strand specificity. We characterize the distinct kinetic signatures generated by these DNA base modifications. PMID:22185597

Direct detection and sequencing of damaged DNA bases.

PubMed

Clark, Tyson A; Spittle, Kristi E; Turner, Stephen W; Korlach, Jonas

2011-12-20

Products of various forms of DNA damage have been implicated in a variety of important biological processes, such as aging, neurodegenerative diseases, and cancer. Therefore, there exists great interest to develop methods for interrogating damaged DNA in the context of sequencing. Here, we demonstrate that single-molecule, real-time (SMRT®) DNA sequencing can directly detect damaged DNA bases in the DNA template - as a by-product of the sequencing method - through an analysis of the DNA polymerase kinetics that are altered by the presence of a modified base. We demonstrate the sequencing of several DNA templates containing products of DNA damage, including 8-oxoguanine, 8-oxoadenine, O6-methylguanine, 1-methyladenine, O4-methylthymine, 5-hydroxycytosine, 5-hydroxyuracil, 5-hydroxymethyluracil, or thymine dimers, and show that these base modifications can be readily detected with single-modification resolution and DNA strand specificity. We characterize the distinct kinetic signatures generated by these DNA base modifications.

Method for conversion of carbohydrate polymers to value-added chemical products

DOEpatents

Zhang, Zongchao C [Norwood, NJ; Brown, Heather M [Kennewick, WA; Su, Yu [Richland, WA

2012-02-07

Methods are described for conversion of carbohydrate polymers in ionic liquids, including cellulose, that yield value-added chemicals including, e.g., glucose and 5-hydroxylmethylfurfural (HMF) at temperatures below 120.degree. C. Catalyst compositions that include various mixed metal halides are described that are selective for specified products with yields, e.g., of up to about 56% in a single step process.

Nitric oxide, PKC-ε, and connexin43 are crucial for ischemic preconditioning-induced chemical gap junction uncoupling.

PubMed

Rong, Bing; Xie, Fei; Sun, Tao; Hao, Li; Lin, Ming-Jie; Zhong, Jing-Quan

2016-10-25

Ischemic preconditioning (IPC) maintains connexin43 (Cx43) phosphorylation and reduces chemical gap junction (GJ) coupling in cardiomyocytes to protect against ischemic damage. However, the signal transduction pathways underlying these effects are not fully understood. Here, we investigated whether nitric oxide (NO) and protein kinase C-ε (PKC-ε) contribute to IPC-induced cardioprotection by maintaining Cx43 phosphorylation and inhibiting chemical GJ coupling. IPC reduced ischemia-induced myocardial infarction and increased cardiomyocyte survival; phosphorylated Cx43, eNOS, and PKC-ε levels; and chemical GJ uncoupling. Administration of the NO donor SNAP mimicked the effects of IPC both in vivo and in vitro, maintaining Cx43 phosphorylation, promoting chemical GJ uncoupling, and reducing myocardial infarction. Preincubation with the NO synthase inhibitor L-NAME or PKC-ε translocation inhibitory peptide (PKC-ε-TIP) abolished these effects of IPC. Additionally, by inducing NO production, IPC induced translocation of PKC-ε, but not PKC-δ, from the cytosolic to the membrane fraction in primary cardiac myocytes. IPC-induced cardioprotection thus involves increased NO production, PKC-ε translocation, Cx43 phosphorylation, and chemical GJ uncoupling.

Aerial pesticide application causes DNA damage in pilots from Sinaloa, Mexico.

PubMed

Martínez-Valenzuela, C; Waliszewski, S M; Amador-Muñoz, O; Meza, E; Calderón-Segura, M E; Zenteno, E; Huichapan-Martínez, J; Caba, M; Félix-Gastélum, R; Longoria-Espinoza, R

2017-01-01

The use of pesticides in agricultural production originates residues in the environment where they are applied. Pesticide aerial application is a frequent source of exposure to pesticides by persons dedicated to agricultural practices and those living in neighboring communities of sprayed fields. The aim of the study was to assess the genotoxic effects of pesticides in workers occupationally exposed to these chemicals during their aerial application to agricultural fields of Sinaloa, Mexico. The study involved 30 pilots of airplanes used to apply pesticides via aerial application and 30 unexposed controls. Damage was evaluated through the micronucleus assay and by other nuclear abnormalities in epithelial cells of oral mucosa. The highest frequency ratios (FR) equal to 269.5 corresponded to binucleated cells followed by 54.2, corresponding to cells with pyknotic nuclei, 45.2 of cells with chromatin condensation, 3.7 of cells with broken-egg, 3.6 of cells with micronucleus, and 2.0 of karyolytic cells. Age, worked time, smoking, and alcohol consumption did not have significant influence on nuclear abnormalities in the pilots studied. Pesticide exposure was the main factor for nuclear abnormality results and DNA damage. Marked genotoxic damage was developed even in younger pilots with 2 years of short working period, caused by their daily occupational exposure to pesticides.

Damage pattern as a function of radiation quality and other factors.

PubMed

Burkart, W; Jung, T; Frasch, G

1999-01-01

An understanding of damage pattern in critical cellular structures such as DNA is an important prerequisite for a mechanistic assessment of primary radiation damage, its possible repair, and the propagation of residual changes in somatic and germ cells as potential contributors to disease or ageing. Important quantitative insights have been made recently on the distribution in time and space of critical lesions from direct and indirect action of ionizing radiation on mammalian cells. When compared to damage from chemicals or from spontaneous degradation, e.g. depurination or base deamination in DNA, the potential of even low-LET radiation to create local hot spots of damage from single particle tracks is of utmost importance. This has important repercussions on inferences from critical biological effects at high dose and dose rate exposure situations to health risks at chronic, low-level exposures as experienced in environmental and controlled occupational settings. About 10,000 DNA lesions per human cell nucleus and day from spontaneous degradation and chemical attack cause no apparent effect, but a dose of 4 Gy translating into a similar number of direct and indirect DNA breaks induces acute lethality. Therefore, single lesions cannot explain the high efficiency of ionizing radiation in the induction of mutation, transformation and loss of proliferative capacity. Clustered damage leading to poorly repairable double-strand breaks or even more complex local DNA degradation, correlates better with fixed damage and critical biological endpoints. A comparison with other physical, chemical and biological agents indicates that ionizing radiation is indeed set apart from these by its unique micro- and nano-dosimetric traits. Only a few other agents such as bleomycin have a similar potential to cause complex damage from single events. However, in view of the multi-stage mechanism of carcinogenesis, it is still an open question whether dose-effect linearity for complex

15 CFR Supplement No. 2 to Part 715 - Examples of Unscheduled Discrete Organic Chemicals (UDOCs) and UDOC Production

Code of Federal Regulations, 2012 CFR

2012-01-01

... Organic Chemicals (UDOCs) and UDOC Production No. Supplement No. 2 to Part 715 Commerce and Foreign Trade... COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING UNSCHEDULED DISCRETE ORGANIC CHEMICALS (UDOCs) Pt. 715, Supp. 2 Supplement No. 2 to Part 715—Examples of Unscheduled Discrete Organic...

15 CFR Supplement No. 2 to Part 715 - Examples of Unscheduled Discrete Organic Chemicals (UDOCs) and UDOC Production

Code of Federal Regulations, 2013 CFR

2013-01-01

... Organic Chemicals (UDOCs) and UDOC Production No. Supplement No. 2 to Part 715 Commerce and Foreign Trade... COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING UNSCHEDULED DISCRETE ORGANIC CHEMICALS (UDOCs) Pt. 715, Supp. 2 Supplement No. 2 to Part 715—Examples of Unscheduled Discrete Organic...

15 CFR Supplement No. 2 to Part 715 - Examples of Unscheduled Discrete Organic Chemicals (UDOCs) and UDOC Production

Code of Federal Regulations, 2011 CFR

2011-01-01

... Organic Chemicals (UDOCs) and UDOC Production No. Supplement No. 2 to Part 715 Commerce and Foreign Trade... COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING UNSCHEDULED DISCRETE ORGANIC CHEMICALS (UDOCs) Pt. 715, Supp. 2 Supplement No. 2 to Part 715—Examples of Unscheduled Discrete Organic...

15 CFR Supplement No. 2 to Part 715 - Examples of Unscheduled Discrete Organic Chemicals (UDOCs) and UDOC Production

Code of Federal Regulations, 2014 CFR

2014-01-01

... Organic Chemicals (UDOCs) and UDOC Production No. Supplement No. 2 to Part 715 Commerce and Foreign Trade... COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING UNSCHEDULED DISCRETE ORGANIC CHEMICALS (UDOCs) Pt. 715, Supp. 2 Supplement No. 2 to Part 715—Examples of Unscheduled Discrete Organic...

Mimicking/extracting structure and functions of natural products: synthetic approaches that address unexplored needs in chemical biology.

PubMed

Hirai, Go

2015-04-01

Natural products are often attractive and challenging targets for synthetic chemists, and many have interesting biological activities. However, synthetic chemists need to be more than simply suppliers of compounds to biologists. Therefore, we have been seeking ways to actively apply organic synthetic methods to chemical biology studies of natural products and their activities. In this personal review, I would like to introduce our work on the development of new biologically active compounds inspired by, or extracted from, the structures of natural products, focusing on enhancement of functional activity and specificity and overcoming various drawbacks of the parent natural products. Copyright © 2014 The Chemical Society of Japan and Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

A large-scale assessment of European rabbit damage to agriculture in Spain.

PubMed

Delibes-Mateos, Miguel; Farfán, Miguel Ángel; Rouco, Carlos; Olivero, Jesús; Márquez, Ana Luz; Fa, John E; Vargas, Juan Mario; Villafuerte, Rafael

2018-01-01

Numerous small and medium-sized mammal pests cause widespread and economically significant damage to crops all over the globe. However, most research on pest species has focused on accounts of the level of damage. There are fewer studies concentrating on the description of crop damage caused by pests at large geographical scales, or on analysis of the ecological and anthropogenic factors correlated with these observed patterns. We investigated the relationship between agricultural damage by the European rabbit (Oryctolagus cuniculus) and environmental and anthropogenic variables throughout Spain. Rabbit damage was mainly concentrated within the central-southern regions of Spain. We found that rabbit damage increased significantly between the early 2000s and 2013. Greater losses were typical of those areas where farming dominated and natural vegetation was scarce, where main railways and highways were present, and where environmental conditions were generally favourable for rabbit populations to proliferate. From our analysis, we suggest that roads and railway lines act as potential corridors along which rabbits can spread. The recent increase in Spain of such infrastructure may explain the rise in rabbit damage reported in this study. Our approach is valuable as a method for assessing drivers of wildlife pest damage at large spatial scales, and can be used to propose methods to reduce human - wildlife conflict. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Recent Advances in Microbial Production of Aromatic Chemicals and Derivatives.

PubMed

Noda, Shuhei; Kondo, Akihiko