Determining Environmental Impacts for Sensitive Species: Using Iconic Species as Bioindicators for Management and Policy

Environmental assessment of impacts, management, and policy are important aspects of protection of human health and the environment. Assessing the impacts of human activities requires selection of bioindicator species that can be used to assess, manage, and develop public policies that ensure ecosystem integrity, and therefore sustainability of social, cultural, and economic systems. With the use of Chinook Salmon (Oncorhynchus tshawytscha), Pacific Cod (Gadusmacrocephalus), Mallard (Anas platyrhynchos), and Red Knot (Calidris canutus rufa), we explore assessment and measurement endpoints, and their relationship to management and development of public policy. This combination of fish and birds provides a diversity of life histories, ecosystem roles, human values, and resource use to explore their use as bioindicators and endpoints. It also allows examination of 1) conservation and protection of species and biodiversity, 2) protection of ecosystems, 3) provision of goods and services, and 4) societal well-being.

In vivo mouse models to study bile acid synthesis and signaling

The synthesis of bile acids(BAs)is carried out by complex pathways characterized by sequential chemical reactions in the liver through various cytochromes P450(CYP)and other enzymes.Maintaining the integrity of these pathways is crucial for normal physiological function in mammals,encompassing hepatic and neurological processes.Studying on the deficiencies in BA synthesis genes offers valuable insights into the significance of BAs in modulating farnesoid X receptor(FXR)signaling and metabolic homeostasis.By creating mouse knockout(KO)models,researchers can manipulate deficiencies in genes involved in BA synthesis,which can be used to study human diseases with BA dysregulation.These KO mouse models allow for a more profound understanding of the functions and regulations of genes responsible for BA synthesis.Furthermore,KO mouse models shed light on the distinct characteristics of individual BA and their roles in nuclear receptor signaling.Notably,alterations of BA synthesis genes in mouse models have distinct differences when compared to human diseases caused by the same BA synthesis gene deficiencies.This review summarizes several mouse KO models used to study BA synthesis and related human diseases,including mice deficient in Cyp7a1,Cyp27a1,Cyp7a1/Cyp27a1,Cyp8b1,Cyp7b1,Cyp2c70,Cyp2a12,and Cyp2c70/Cyp2a12,as well as germ-free mice.

A novel fibroblast growth factor 15-dependent and bile acid-independent promotion of liver regeneration in mice

Objective:The role of intestine-derived factors in promoting liver regeneration after partial hepatectomy(PHx)are not entirely known,but bile acids(BAs)and fibroblast growth factor 15(Fgf15)that are highly expressed in the mouse ileum could promote hepatocyte proliferation.Fgf15 strongly suppresses the synthesis of BAs,and emerging evidence indicates that Fgf15 is important for liver regeneration.

Inhalation treatment of lung cancer: the influence of composition, size and shape of nanocarriers on their lung accumulation and retention

Objective: Various nanoparticles have been designed and tested in order to select optimal carriers for the inhalation delivery of anticancer drugs to the lungs. Methods: The following nanocarriers were studied: micelles, liposomes, mesoporous silica nanoparticles(MSNs), poly propyleneimine(PPI) dendrimer-siRNA complexes nanoparticles, quantum dots(QDs), and poly(ethylene glycol) polymers. All particles were characterized using the following methods: dynamic light scattering, zeta potential, atomic force microscopy, in vitro cyto- and genotoxicity. In vivo organ distribution of all nanoparticles, retention in the lungs, and anticancer effects of liposomes loaded with doxorubicin were examined in nude mice after the pulmonary or intravenous delivery. Results: Significant differences in lung uptake were found after the inhalation delivery of lipid-based and non-lipid-based nanoparticles. The accumulation of liposomes and micelles in lungs remained relatively high even 24 h after inhalation when compared with MSNs, QDs, and PPI dendrimers. There were notable differences between nanoparticle accumulation in the lungs and other organs 1 and 3 h after inhalation or intravenous administrations, but 24 h after intravenous injection all nanoparticles were mainly accumulated in the liver, kidneys, and spleen. Inhalation delivery of doxorubicin by liposomes significantly enhanced its anticancer effect and prevented severe adverse side effects of the treatment in mice bearing the orthotopic model of lung cancer.Conclusion: The results of the study demonstrate that lipid-based nanocarriers had considerably higher accumulation and longer retention time in the lungs when compared with non-lipid-based carriers after the inhalation delivery. These particles are most suitable for effective inhalation treatment of lung cancer.

Habitat protection for sensitive species: Balancing species requirements and human constraints using bioindicators as examples

Vertebrates have particular habitat needs as a function of life cycle and reproductive stage. This paper uses four species as examples to illustrate a paradigm of environmental assessment that includes physical, biological, toxicological and human dimensions. Species used include Chinook salmon (Oncorhynchus tshawytscha), northern leopard frog (Rana pipiens), northern pine snake (Pituophis m. melanoleucus), and red knot (Calidris canutus rufa, a sandpiper). The life cycles of these species include reliance on habitats that are aquatic, terrestrial, aerial, or combinations of these. Two species (frog, snake) are sedentary and two (salmon, sandpiper) are long-distance migrants. While some measurement endpoints are similar for all species (reproductive success, longevity, contaminant loads), others vary depending upon life cycle and habitat. Salmon have a restricted breeding habitat requiring coarse sand, moderate current, and high oxygen levels for adequate egg incubation. Leopard frogs require still water of appropriate temperature for development of eggs. Pine snakes require sand compaction sufficient to sustain a nest burrow without collapsing, and full sun penetration to the sand to allow their eggs in underground nests to incubate and hatch. Red knots migrate to high Arctic tundra, but incubate their own eggs, so temperature is less of a constraint, but feedinging habitat is. These habitat differences suggest the measurement endpoints that are essential to assess habitat suitability and to manage habitats to achieve stable and sustainable populations. Habitat use and population stability have implications for human activities for some, but not all species. Salmon are important economically, recreationally, and as part of Native American culture and diet. Red knots are of interest to people mainly because of their long, intercontinental migrations and declining populations. Other measurement endpoints for these four species illustrate the differences and similarities in metrics necessary to assess habitat needs. The implications of these differences are discussed.

Knowledge and Perceptions of Energy Alternatives, Carbon and Spatial Footprints, and Future Energy Preferences within a University Community in Northeastern US

Our overall research aim was to examine whether people distinguished between the spatial footprint and carbon footprint of different energy sources, and whether their overall “worry” about energy types was related to future developed of these types. We surveyed 451 people within a university community regarding knowledge about different energy sources with regard to renewability and spatial and carbon footprints and attitudes about which energy type(s) should be developed further. Findings were: 1) Gas, oil and coal were rated as the least renewable, and wind, solar and hydro as the most renewable;2) Oil and coal were rated as having the largest carbon footprint, while wind, solar and tidal were rated the lowest;3) There were smaller differences in ratings for spatial footprints, probably reflecting unfamiliarity with the concept, although oil and gas were rated the highest;4) Energy sources viewed as renewable were favored for future development compared with non-renewable energy sources, and coal and oil were rated the lowest;5) Worry-free sources such as solar were favored;and 6) There were some age-related differences, but they were small, and there were no gender-related differences. Overall, subjects knew more about carbon footprints than spatial footprints, generally correctly identified renewable and non-renewable sources, and wanted future energy development for energy sources which were less worried about (e.g. solar, wind). These perceptions require in-depth examination in a large sample from different areas of the country.

Perceptions of Climate Change, Sea Level Rise, and Possible Consequences Relate Mainly to Self-Valuation of Science Knowledge

This study examines perceptions of climate change and sea level rise in New Jersey residents in 2012 and 2014. Different surveys have shown declines in interest and concern about climate change and sea level rise. Climate change and increasing temperatures have an anthropogenic cause, which relates to energy use, making it important to examine whether people believe that it is occurring. In late 2012 New Jersey experienced Super storm Sandy, one of the worst hurricanes in its history, followed by public discussion and media coverage of stronger more frequent storms due to climate change. Using structured interviews, we tested the null hypotheses that there were no differences in perceptions of 1260 interviewees as a function of year of the survey, age, gender, years of education, and self-evaluation of science knowledge (on a scale of 1 to 5). In 2012 460 of 639 (72%) rated “global warming occurring” as “certain” (#4) or “very certain” (#5) compared with 453 of 621 (73%) in 2014. For “due to human activities” the numbers of “certain” or “very certain” were 71% in 2012, and 67% in 2014 and for sea level rise the numbers were 64% and 70%. There were some inconsistent between-year differences with higher ratings in 2012 for 3 outcomes and higher ratings in 2014 for 5 outcomes. However, for 25 questions relative to climate change, sea level rise, and the personal and ecological effects of sea level rise, self-evaluation of science knowledge, independent of years of education, was the factor that entered 23 of the models, accounting for the most variability in ratings. People who believed they had a “high knowledge” (#4) or “very high knowledge” (#5) of science rated all issues as more important than did those people who rated their own scientific knowledge as average or below average.

The Importance of Preserving Birds and Their Habitats at Hanford Site and Oak Ridge Reservation: Information and Communication Tools for Governments, Local and Diverse Communities and Others

The Department of Energy (DOE) has one of the largest environmental remediation tasks in the world, cleaning up the radiologic and toxic contamination legacy of nuclear weapons production. DOE has committed itself to accomplish remediation “while protecting human health and the environment”. Many DOE sites are huge, encompassing habitats that are ecologically valuable because they have been protected from human disturbance for 70 years or more. Yet information on the importance of DOE lands for protecting specific ecological resources is often buried in volumes of data. In this paper, we examine the importance of DOE lands as habitats for birds using two sites as examples: the Hanford Site and Oak Ridge Reservation. Our overall goal was to provide a model for communication of key information useful for the public and decision-makers. Birds are conspicuous and familiar features of the landscape, and bird populations are important indicators of habitat quality. As future land use plans evolve, birds can convey important messages about habitat uniqueness and conservation importance and recreational values of designating DOE land for conservation, but only if they are in accessible formats. At the semi-arid Hanford site, shrub-steppe is an important habitat outside the Columbia River corridor. At the wet Oak Ridge Reservation eastern deciduous forest, interior forest is a particularly important habitat. There are different groups of bird species dependent on each habitat. We use two methods for each habitat: 1) a comparison of historical written records and 2) a comparison of land use/land cover data. Habitat loss through development, fragmentation, and degradation is one of the most important causes of avian decline. Importantly, we present the data in a manner suitable for discussion among diverse audiences regarding future use of sites now undergoing remediation. The Hanford Site has recorded 205 bird species, including shrub-steppe species of regional importance. The Oak Ridge Reservation has recorded 213 species of birds, including Neotropical migrants of international concern. In both cases, their respective habitat is key to protection of the unique avian assemblages, and there is a higher percentage of these habitats on the DOE lands than in the surrounding habitats. Our analysis also concludes that these habitats that are of high importance to the rare and declining avian assemblages are mostly increasing on the DOE sites as the once agrarian landscape has reverted to more natural habitat. Since acquisition, DOE has developed about 10% of the land for nuclear and industrial activities, leaving the rest of it as a security buffer for the nuclear production mission. The tables provided in this manuscript can serve as valuable tools in communicating the importance of these lands and protecting these lands for surrounding communities. We commend the DOE for its protection of ecological resources for the regions and the Nation, applaud their mechanisms for ecological protection, and recommend that more of each site’s respective unique and important habitats be designated as preserved in perpetuity as valued ecological resources. This designation entails communicating with Tribes, communities, government agencies and organizations, and the public about the ecological value of their protected lands.

空气污染与儿童呼吸系统患病率的相关分析

在流行病学调查和空气污染物监测的基础上，研究讨论了儿童呼吸系统患病率与空气污染之间的相关关系，结果表明，空气中细颗粒物（PM2.5）和可吸入颗粒物（PM10）与儿童呼吸系统患病率呈线性正相关关系，其影响比SO2、NOx更密切．哮喘明显受颗粒物、SO2、NOx的综合作用的影响．未感冒咳嗽发生率明显受细颗粒物和NOx污染综合作用的影响．

空气污染对儿童及其父母呼吸系统健康的影响

根据空气污染数据对广州、武汉、兰州、重庆4城市8个点位进行了空气污染的聚类分析,并按空气污染程度进行了排序.在此基础上,分析了空气污染程度与儿童及其父母呼吸系统健康的关系.发现儿童11种患病率随空气污染程度加重而呈上升趋势.污染最重组的患病率是污染较轻组的1.71(3.95倍.污染最重组的比数比(即OR值)是污染较轻组的3.313(6.942倍.空气污染对儿童父母的呼吸系统患病率也有轻度至中度的影响.

用尿中1-羟基芘评价人体暴露PAHs的肺癌风险

采集并分析了100名不吸烟成人24h呼吸的空气样品和尿液样品,建立了人尿中1-羟基芘(1-OH-Py)浓度与苯并(a)芘(BaP)、芘(Py)等14种多环芳烃(PAHs)呼吸暴露浓度的定量关系.参考现有关于BaP空气污染浓度与肺癌死亡率的剂量-反应关系模型,推导出用尿中1-OH-Py预测人体呼吸暴露PAHs的肺癌风险模型.用建立的模型对100名受试者进行了肺癌风险评价,结果表明,一般人群BaP暴露的肺癌风险约为11/10万,焦炉工人约为160/10万;若同时考虑14种PAHs的BaP当量毒性,则其相应肺癌风险要高出约0.5倍.一般人群的尿中1-OH-Py的生物暴露限值为0.11μmol/mol肌酐,焦炉工人为1.90μmol/mol肌酐.

不同工作环境人群多环芳烃的日暴露总量

研究了100名处于不同工作与生活环境人群14种PAHs化合物的24h个体呼吸(PM10和气相)及饮食暴露量.结果表明,参试人群按PAHs暴露量从大到小顺序排列为焦炉炉顶工人>焦炉炉侧工人>焦炉炉底工人>炼钢管理人员>办公室工作人员.焦炉工人BaP日暴露量可达8～25μg/d;焦炉工人PAHs日暴露量为一般人群的几十至上百倍,造成差异的原因主要是不同人群日呼吸暴露量的不同,而饮食暴露量的组间差异不大;除二苯并(a,h)蒽外的13种PAHs化合物日暴露量两两呈显著正相关.

儿童肺功能的多因子及交互影响分析

在儿童肺功能横断面数据基础上,运用多元线性回归,研究了影响儿童肺功能的多因子及其交互效应.结果表明,儿童肺功能指标主要受儿童基本体质情况、呼吸系统疾病和家庭室内暴露因子以及这些因子的交互影响.儿童肺功能与空气颗粒物(PM10-2.5和TSP)的负相关比较显著,未发现与SO2和NOx有显著相关性.作者还对空气颗粒物与年均取暖期燃煤取暖、母乳喂养、呼吸系统疾病等因子的交互效应进行了研究,发现细颗粒物对儿童肺功能的影响更为不利.

空气污染与呼吸系统疾病对儿童肺功能的交互影响

在中国 4城市儿童肺功能的队列研究数据基础上 ,通过 3步回归的统计方法 ,就空气污染和支气管炎或哮喘的交互作用对儿童肺功能的影响进行了研究。结果发现 ,空气颗粒物与支气管炎或哮喘等呼吸系统疾病对儿童肺功能有不利影响 ,而儿童在短期内患过支气管炎或哮喘会显著地加重空气颗粒物污染对 FVC和 FEV1 的有害影响 ,但从长期来看 ,这种有害影响趋于减弱。对于 FEV1/ FVC,支气管炎或哮喘与空气颗粒物对肺功能的作用是独立的。与气态污染物相比 。

室内燃煤与大气污染对儿童肺功能的交互影响

目的研究室内燃煤与大气污染对儿童肺功能的交互作用影响。方法1995-1996年间在中国4城市的城区和郊区的8所小学对6～12岁的儿童进行肺功能的队列测试,每年分冷、暖两季进行。通过3步回归过程进行统计分析。结果室外空气颗粒物与儿童第1秒最大呼气量(FEV1)、用力肺活量(FVC)和FEV1/FVC都有显著的负相关关系。家庭燃煤与TSP对FEV1和FVC有较显著的交互作用。家庭燃煤与PM10对肺功能的交互作用较弱,但有加重颗粒物对肺功能产生不利影响的趋势。未发现室内燃煤与SO2和NOx对肺功能有显著的交互影响作用。结论家庭燃煤这种室内污染因素加重了环境空气颗粒物污染,特别是TSP对儿童肺功能的不利影响。

第208位异亮氨酸对人细胞色素P4502A6尼古丁代谢活性的影响

目的探讨人体尼古丁主要代谢酶细胞色素P450(CYP)2A6及其同族成员CYP2A13肽链结构中,影响其尼古丁5′-羟化代谢活性的关键性氨基酸残基。方法使用前期制备的CYP2A6和CYP2A13系列氨基酸互换突变体:CYP2A6V117A,CYP2A6G164H,CYP2A6I208S,CYP2A6R372H和CYP2A6S465P以及CYP2A13A117V,CYP2A13H164G,CYP2A13S208I,CYP2A13H372R和CYP2A13P465S,比较其与相应野生蛋白酶的尼古丁5′-羟化催化反应的动力学参数。结果各突变体对2个CYP2A蛋白酶的尼古丁代谢活性影响不同。对于CYP2A6,I208S突变对酶活性的影响显著,导致表观反应常数Km及最大反应速度Vmax由野生型62.25μmol.L-1和6.53mol.min-1.mol-1变化为345μmol.L-1和2.19mol.min-1.mol-1,但该位点对CYP2A13酶活性无显著影响;对于CYP2A13,H372R突变对酶活性的影响最为显著,导致Km及Vmax由野生型的26.01μmol.L-1和24.51mol.min-1.mol-1变为148.7μmol.L-1和6.11mol.min-1.mol-1,此位点对CYP2A6无显著影响。其他位点突变对酶活性影响较小或不显著。结论CYP2A家族蛋白中,I208与H372分别是影响CYP2A6和CYP2A13对尼古丁代谢的关键残基。对于同家族蛋白酶而言,关键性氨基酸的作用并不总是一一对应。

Critical Amino Acid Residues for Nicotine 5'-Hydroxylation in Human CYP2A Enzymes

Objective： We have continued previous work in which we demonstrated that #117 and #372 amino acids contributed to the high activities of human CYP2A13 in catalyzing 4-methylnitrosamino-1-（3-pyridyl）-1-butanone（NNK） and aflatoxin BI（AFB1） carcinogenic activation. The present study was designed to identify other potential amino acid residues that contribute to the different catalytic characteristics of two CYP2A enzymes, CYP2A6 and CYP2A13, in nicotine metabolism and provide insights of the substrate and related amino acid residues interactions. Methods： A series of reciprocally substituted mutants of CYP2A6lle^300→ Phe, CYP2A6Gly^301aAla, CYP2A6Ser^369 → Gly, CYP2A13Phe^300→ Ile, CYP2A13Ala^301 → Gly and CYP2A13Gly^369 → Set were generated by site-directed mutagenesis/baculovirus-Sf9 insect cells expression. Comparative kinetic analysis of nicotine 5＇hydroxylatin by wild type and mutant CYP2A proteins was performed. Results：All amino acid residue substitutions at 300, 301 and 369 caused significant kinetic property changes in nicotine metabolism. While CYP2A6Ile^300→ Phe and CYP2A6Gly^301→Ala mutations had notable catalytic efficiency increases compared to that for the wild type CYP2A6, CYP2A13Phe^300→Ile and CYP2A13Ala^301→Gly replacement introduced remarkable catalytic efficiency decreases. In addition, all these catalytic efficiency alterations were caused by Vmax variations rather than Km changes. Substitution of #369 residue significantly affected both Km and Vmax values. CYP2A6Ser^369 → Gly increase the catalytic efficiency via a significant Km decrease versus Vmax enhancement, while the opposite effects were seen with CYP2A13Gly^369 → Ser. Conclusion：#300, #301 and #369 residues in human CYP2A6/13 play important roles in nicotine 5＇ -oxidation. Switching #300 or #301 residues did not affect the CYP2A protein affinities toward nicotine, although these amino acids are located in the active center. Set369 to Gly substitution indirectly affected nicotine binding by creating more space and conformational flexibility for the nearby residues, such as Leu^370 which is crucial for many hydroxylations.

Fatty liver diseases,bile acids,and FXR

The prevalence of nonalcoholic fatty liver disease(NAFLD) worldwide has increased at an alarming rate,which will likely result in enormous medical and economic burden.NAFLD presents as a spectrum of liver diseases ranging from simple steatosis,nonalcoholic steatohepatitis(NASH),fibrosis,cirrhosis,and even to hepatocellular carcinoma(HCC).A comprehensive understanding of the mechanism(s) of NAFLD-to-NASH transition remains elusive with various genetic and environmental susceptibility factors possibly involved.An understanding of the mechanism may provide novel strategies in the prevention and treatment to NASH.Abnormal regulation of bile acid homeostasis emerges as an important mechanism to liver injury.The bile acid homeostasis is critically regulated by the farnesoid X receptor(FXR) that is activated by bile acids.FXR has been known to exert tissue-specific effects in regulating bile acid synthesis and transport.Current investigations demonstrate FXR also plays a principle role in regulating lipid metabolism and suppressing inflammation in the liver.Therefore,the future determination of the molecular mechanism by which FXR protects the liver from developing NAFLD may shed light to the prevention and treatment of NAFLD.