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云南省野生牛肝菌总汞含量测定分析及健康风险评估

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云南农业大学学报（自然科学版） 2017年第3期32卷 523-535页

作者：李杰庆杨天伟张霁 Jerzy FALANDYSZ grazyna krasiNska Martyna SABA 王元忠刘鸿高云南农业大学农学与生物技术学院云南昆明650201 云南省热带作物科学研究所云南景洪666100 云南省农业科学院药用植物研究所云南昆明650200 云南省省级中药原料质量监测技术服务中心云南昆明652000 格但斯克大学波兰格但斯克80-308

【目的】系统测定云南常见野生牛肝菌中总Hg含量,分析不同产地、种类及不同部位牛肝菌对Hg的富集规律和积累特征,评价野生牛肝菌的食用安全性,为野生食用菌产业的发展和食用安全评估提供数据依据。【方法】采用MA-2000直接测Hg仪—冷原... 详细信息

【目的】系统测定云南常见野生牛肝菌中总Hg含量,分析不同产地、种类及不同部位牛肝菌对Hg的富集规律和积累特征,评价野生牛肝菌的食用安全性,为野生食用菌产业的发展和食用安全评估提供数据依据。【方法】采用MA-2000直接测Hg仪—冷原子吸收光谱法测定牛肝菌菌盖、菌柄中总Hg含量,计算同一牛肝菌菌盖与菌柄总Hg含量比(QC/S),分析不同种类、部位牛肝菌中总Hg含量的差异和富集规律。根据中国《食品安全国家标准食品中污染物限量》(GB 2762—2012)规定的食用菌中Hg限量标准及联合国粮农组织和世界卫生组织(FAO/WHO)规定的每周Hg允许摄入量(provisional tolerable weekly intake,PTWI)现行标准,评价云南野生牛肝菌的食用安全性。【结果】同一子实体菌盖与菌柄的比值(QC/S)在0.3~8.8之间,95%牛肝菌样品菌盖、菌柄总Hg含量比(QC/S)≥1,表明多数牛肝菌菌盖对Hg的富集能力强于菌柄。本研究中多数野生牛肝菌菌盖、菌柄总Hg含量超过GB 2762—2012规定的食用菌中Hg含量限量标准(≤0.1 mg/kg);根据PTWI标准,假设成年人(60 kg)每周食用300 g新鲜牛肝菌,则多数样品Hg摄入量低于允许摄入量,无安全风险,而2013年采自玉溪大营街的美味牛肝菌,2012年采自楚雄永仁县的铜色牛肝菌及2014年采自玉溪新平的绒柄牛肝菌等少数样品Hg摄入量高于该标准。【结论】不同产地、种类牛肝菌菌盖、菌柄中总Hg含量存在明显差异,有少数牛肝菌总Hg含量超过相关标准,食用具有一定的潜在风险。

关键词：牛肝菌健康风险汞重金属食品安全

Sensitivity of the area method with mono isotopic fission chambers to reactivity changes in subcritical nuclear reactors

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Nuclear Science and Techniques 2021年第10期32卷 166-176页

作者： Jerzy A.Janczyszyn grazyna Domanska Przemysław Stanisz Faculty of Energy and Fuels AGH University of Science and Technologyal.Mickiewicza 3030-0591 KrakowPoland

High-level waste is an important safety issue in the development of nuclear power.A proposed solution is the transmutation of waste in fast *** exclusion of the risk of supercriticality by using subcritical reactors is currently under *** the subcriticality level in such reactors presents difficulties.A problem is posed by the so-called space effect observed when using in reactors many neutron detectors in different locations of the core and *** obtained from measure-ments,for example,by the Sjo¨strand method,differs by nonnegligible *** corrections can partially improve this *** use of a monoisotopic fission chamber set,designed for a given reactor,when each chamber is intended for a specific position in the system,can improve the situation.A question arises about the sensitivity of the results to reactivity *** issue is analyzed by computer simulation for possible fissionable and fissile nuclides for the total range of control rod insertion,changes in reactor fuel enrichment,and fuel *** tested sensitivity was satisfactory at most levels from several dozen to several hundred pcm.A case study was conducted using the VENUS-F core model.

关键词： Subcriticality Simulation Sjostrand method Fission chambers Space effect

Microstructure and electrical resistivity in the GdNi_(5–x)Cu_x intermetallic series

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Journal of Rare Earths 2017年第1期35卷 71-78页

作者： Anna Bajorek grazyna Chelkowska A. Chelkowski Institute of Physics University of Silesia Katowice Poland Silesian Center for Education and Interdisciplinary Research University of Silesia Chorzow Poland

The effect of the Ni/Cu substitution on the electrical resistivity and microstructure of the polycrystalline GdNi5-xCux series was studied. The value of temperature of phase transition（T_（ph）） estimated from temperature dependence of electrical resistance varied non-linearly across copper doping from 32.5 K（x=0.0） to 29.1 K（x=5.0）. The value of residual resistivity（ρo） estimated at low temperature range decreased from 27.28 μΩcm（x=0.0） to 9.44 μΩcm（x=5.0）, which was discussed as the influence of microstructure. In order to describe the temperature dependence of resistivity ρ（T） a variety of approaches were applied due to different scattering mechanisms occurring at high and low temperature ranges. The change within ρ（T） curvature was evidenced at low temperature range across copper doping. The temperature variation of the resistivity was quite peculiar for Cu-rich compounds（x=4.8, x=5.0）, which might be correlated with the incommensurate magnetic structure derived from the weakly negative interaction between the nearest neighbours of Gd. The correlation between microstructure and resistivity was observed.

关键词： intermetallics rare earth alloys and compounds crystal structure electrical resistivity scanning electron microscopy

Thermal and radiative characteristics of oxyfluoride glass singly doped with lanthanide ions

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Journal of Rare Earths 2010年第6期28卷 893-898页

作者： Barbara KLIMESZ grazyna DOMINIAK-DZIK Witold RYBA-ROMANOWSKI Department of Physics Opole University of Technology Institute of Low Temperature and Structure Research Polish Academy of Sciences

Rare earths-doped oxyfluoride glasses based on germanium oxide and lead fluoride were prepared from commercial raw materials. The glasses with general composition of 50GeO2-(50-x-y)PbO-yPbF2-xLnF3 (Ln=Pr3+-Yb3+), contained different concentrations of optically active dopants (x=0.2 mol.% and 2 mol.%) and PbF2 (y≤15 mol.%). The differential thermal analysis (DTA) was used to determine both thermal characteristic and thermal stability properties of the glasses in the function of the kind of dopant, its concentration, and a glass composition. Characteristic glass temperatures such as glass transition temperature (Tg), glass crystallization temperature (Tc) and temperature corresponding to the maximum of the crystallization rate (Tpc) were evaluated. On the basis of obtained results, the thermal stabilities of glasses under study were evaluated using various thermal stability criteria (Dietzel factor ?T, Saad-Poulain factors H’ and S). It was found that the increase in rare earth fluoride contents influenced thermal characteristics when the characteristic temperatures of the individual glass was shifted towards higher values. The effect of the PbF2 content and the kind of rare earth impurity on the glass stability was observed. Absorption spectra of lanthanide-doped glasses were measured at room temperature and used to determine the phenomenological intensity parameters Ωt and next, to estimate radiative properties of lanthanide ions in this matrix. Radiative transition probabilities of luminescent states of Ln3+, branching ratios and radiative lifetimes were determined. The variation of the Ωt along the lanthanide series was presented and discussed.

关键词： oxyfluoride glasses rare earths DTA thermal stability of glasses radiative transition probabilities radiative lifetimes

Tufted Hairgrass(Deschampsia caespitosa)Exhibits a Lower Photosynthetic Plasticity than Antarctic Hairgrass(***)

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Journal of Integrative Plant Biology 2009年第6期51卷 593-603页

作者： grazyna Bystrzejewska-Piotrowska Pawel L.Urban Isotope Laboratory Faculty of Biology University of Warsaw02-096 Warsaw Miecznikowa 1 Poland

The aim of our work was to assess photosynthetic plasticity of two hairgrass species with different ecological origins （a temperate zone species, Deschampsia caespitosa （L.） Beauv. and an Antarctic species, D. antarctica） and to consider how the anticipated climate change may affect vitality of these plants. Measurements of chlorophyll fluorescence showed that the photosystem Ⅱ （PSⅡ） quantum efficiency of D. caespitosa decreased during 4 d of incubation at 4℃ but it remained stable in D. antarctica. The fluorescence half-rise times were almost always lower in D. caespitosa than in D. antarctica, irrespective of the incubation temperature. These results indicate that the photosynthetic apparatus of D. caespitosa has poorer performance in these conditions. D. caespitosa reached the maximum photosynthesis rate at a higher temperature than D. antarctica although the values obtained at 8 ℃ were similar in both species. The photosynthetic water-use efficiency （photosynthesis-to-transpiration ratio, PIE） emerges as an important factor demonstrating presence of mechanisms which facilitate functioning of a plant in non-optimal conditions. Comparison of the PiE values, which were higher in D. antarctica than in D. caespitosa at low and medium temperatures, confirms a high degree of adjustability of the photosynthetic apparatus in D. antarctica and unveils the lack of such a feature in D. caespitosa.

关键词： chlorophyll fluorescence climate change Deschampsia photosynthesis photosynthetic water-use efficiency.

Culturomics and metagenomics: In understanding of environmental resistome

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Frontiers of Environmental Science & Engineering 2019年第3期13卷 29-40页

作者： Monika Nowrotek Lukasz Jalowiecki Monika Harnisz grazyna Anna Plaza Microbiology Unit Institute for Ecology of Industrial Areas Kossutha 6 Str. 40-844 Katowice Poland Department of Environmental Microbiology Faculty of Environmental Sciences University of Warmia and Mazuiy Prawochenskiego 1 Str. 10-720 Olsztyn Poland Silesian University of Technology Faculty of Organization and Management Institute of Engineering Production Roosevelta 26 Str. 41-800 Zabrze Poland

Pharmaceutical residues, mainly antibiotics, have been called "emerging contaminants" in the environment because of their increasing frequency of detection in aquatic and terrestrial systems and their sublethal ecological effects. Most of them are undiscovered. Both human and veterinary pharmaceuticals, including antibiotics, are introduced into the environment via many different routes, including discharges from municipal wastewater treatment plants and land application of animal manure and biosolids to fertilize croplands. To gain a comprehensive understanding of the widespread problem of antibiotic resistance, modem and scientific approaches have been developed to gain knowledge of the entire antibiotic-resistant microbiota of various ecosystems, which is called the resistome. In this review, two omics methods, i.e. culturomics, a new approach, and metagenomics, used to study antibiotic resistance in environmental samples, are described. Moreover, we discuss how both omics methods have become core scientific tools to characterize microbiomes or resistomes, study natural communities and discover new microbes and new antibiotic resistance genes from environments. The combination of the method for get better outcome of both culturomics and metagenomics will significantly advance our understanding of the role of microbes and their specific properties in the environment.

关键词： Culturomics Metagenomics Antibiotic resistance Resistome

Risk of venous thromboembolic disease in postmenopausal women taking oral or transdermal hormone replacement therapy

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第1期12卷 12-17页

作者： Barbara RUSZKOWska grazyna GADOMska Liliana BIELIS Marzena GRUSZKA Barbara GóRALCZYK Danuta RO grazyna ODROWAZ-SYPNIEWska Department of Pathophysiology Collegium Medicum in BydgoszczNicolaus Copernicus University in Toruń Department of Laboratory Medicine Collegium Medicum in BydgoszczNicolaus Copernicus University in Toruń Department of Laboratory Medicine Collegium Medicum in BydgoszczNicolaus Copernicus University in Toruń

Objective: The influence of hormone replacement therapy (HRT) on hemostasis processes depends on the type of hormone,the combination of doses,the time of taking HRT,and the route of administration (oral,transdermal,implanted).The aim of the current study was to assess some parameters of coagulation,especially tissue factor pathway inhibitor (TFPI) and tissue factor (TF) in postmenopausal women using oral or transdermal ***: The study was conducted on 76 healthy women,including 46 women aged 44–58 years who were taking oral (26) or transdermal (20) HRT,and 30 women aged 44–54 years who did not take HRT as the control *** concentrations of TF,TFPI,thrombin-antithrombin complex (TAT),and D-dimer were performed by enzyme-linked immunosorbent assay (ELISA).Moreover,the concentration of fibrinogen and activity of protein C were measured by chromogenic and chronometric ***: We observed a significantly higher concentration of TF and a significantly lower concentration of TFPI in women taking oral and transdermal HRT in comparison with the control *** also found a significantly lower concentration of fibrinogen in women taking oral HRT *** control ***,no statistically significant changes in concentrations of TAT and D-dimer,or activity of protein C were ***: In this study,the occurrence of an increased TF concentration simultaneously with a decreased concentration of TFPI in women taking HRT indicates *** significant modification of TAT or D-dimer occurred,and thus there may not be increased risk of thrombosis.

关键词： Menopause Coagulation Hormone replacement therapy

Coexistence of hepatocellular carcinoma and gastrointestinal stromal tumor:A case report

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World Journal of Gastroenterology 2006年第4期12卷 665-667页

作者： RadoslawJaworski TomaszJastrzebski MaciejSwierblewski KamilDrucis grazyna Kobierska-Gulida Department of Surgical Oncology Medical University of GdanskPoland Department of Pathology Medical University of GdanskPoland

Malignant gastrointestinal stromal tumors （GIST） are rare mesenchymal tumors originating from the wall of the gastrointestinal tract. Their coexistence with other tumors originating from other germ layers is unique. We have reported a case of a 63-year-old GIST patient presenting as an epigastric mass associated with hepatic tumor. Histologically, the mesenteric tumor was composed of spindle cells showing both neural and smooth muscle differentiation. Immunohistochemical examination showed positive staining for CDl17, vimentin, S-100, and SMA, while CD34 antigen was negative. The hepatic tumor was diagnosed as hepatocellular carcinoma （HCC）. To the best of our knowledge, this is the first case of GIST and HCC coexistence. The rarity of the case, however, should not lead to ignoring such a possibility in differential diagnosis.

关键词： Malignant GIST Hepatocellular carcinoma Coexistence of GIST and HCC

TT virus infection and pancreatic cancer: Relationship or accidental coexistence

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World Journal of Gastroenterology 2005年第18期11卷 2847-2849页

作者： Krzysztof Tomasiewicz Roma Modrzewska Anna Lyczak grazyna Krawczuk Department of Infectious Diseases Medical University of Lublin Biernackiego 9 20-089 Lublin Poland

TT virus (TTV) was first isolated in 1997 from the patient with acute post-transfusion hepatitis. This fact led to the conclusion that the virus was hepatotropic and could be one of the causative agents of acute hepatitis. Afterwards, however, the virus was found in other human tissues and serological studies revealed that it was widespread. Multiple tropisms of TTV and the fact of its high incidence in general population are considered to indicate no medical significance of TTV in human pathology. Here we present a report of two cases of TTV infection in patients who developed pancreas cancer. The patients were hospitalized at the Department of Infectious Diseases due to hepatitis of unknown origin. Since serological and virological markers of common primary and secondary hepatotropic viruses were negative, TTV-DNA was found in serum and was believed to be the only causative agent with probable hepatotropic action. The patients later developed pancreas cancer and they underwent operation. The relationship is difficult to confirm, however the cases we present should be treated as a preliminary report and a comment on the real role of TTV in human pathology.

关键词： TT virus Hepatitis Pancreas cancer Hepatotropic viruses