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Regulatory T cells in viral hepatitis

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World Journal of Gastroenterology 2007年第36期13卷 4858-4864页

作者： eva Billerbeck Tobias Bttler Robert Thimme Department of Medicine Ⅱ University Hospital Freiburg Germany

The pathogenesis and outcome of viral infections are significantly influenced by the host immune response. The immune system is able to eliminate many viruses in the acute phase of infection. However, some viruses, like hepatitis C virus (HCV) and hepatitis B virus (HBV), can evade the host immune responses and establish a persistent infection. HCV and HBV persistence is caused by various mechanisms, like subversion of innate immune responses by viral factors, the emergence of T cell escape mutations, or T cell dysfunction and suppression. Recently, it has become evident that regulatory T cells may contribute to the pathogenesis and outcome of viral infections by suppressing antiviral immune responses. Indeed, the control of HCV and HBV specific immune responses mediated by regulatory T cells may be one mechanism that favors viral persistence, but it may also prevent the host from overwhelming T cell activity and liver damage. This review will focus on the role of regulatory T cells in viral hepatitis.

关键词： Regulatory T cells Viral hepatitis Immunoregulation

Gromov Hyperbolicity of Riemann Surfaces

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Acta Mathematica Sinica,English Series 2007年第2期23卷 209-228页

作者： José M.RODRíGUEZ eva TOURIS Departamento de Matemáticas Universidad Carlos Ⅲ de MadridAvenida de la Universidad 3028911 LeganésMadridSpain

We study the hyperbolicity in the Gromov sense of Riemann surfaces. We deduce the hyperbolicity of a surface from the hyperbolicity of its ＂building block components＂. We also prove the equivalence between the hyperbolicity of a Riemann surface and the hyperbolicity of some graph associated with it. These results clarify how the decomposition of a Riemann surface into Y-pieces and funnels affects the hyperbolicity of the surface. The results simplify the topology of the surface and allow us to obtain global results from local information.

关键词： Gromov hyperbolicity hyperbolic Riemann surface

Simple phenols in tropical woods determined by UHPLC-PDA and their antioxidant capacities: an experimental design for Randall extraction using environmentally friendly solvents

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Journal of Forestry Research 2020年第3期31卷 819-826页

作者： Marie Bartakova eva Dvorackova Lucie Chromcova Petr Hrdlicka Department of Chemistry and Biochemistry Mendel University in BrnoZemedelska 161300 BrnoCzech Republic

A comprehensive experimental design was developed to determine suitable conditions(volume, percentage of solvent, extraction temperature) for the ethanol extraction of phenolic compounds from ten tropical woody plants. Wenge, angelim vermelho, zebrano, merbau,tigerwood, angelim pedra, jatoba, angelim amargoso,massaranduba, and doussie woods were used in experiments. The effects of three independent variables and their interactions on the yields of cinnamic and benzoic acid derivates were analyzed using UHPLC-PDA. The most significant parameters were found to be solvent percentage,extraction volume, and extraction temperature. Optimal conditions for the extraction of phenolic compound contents were an 80℃ extraction temperature, a 30 mL extraction volume, and the use of pure water as the extraction solvent. The tested species of woods contained mainly cinnamic acid derivates. Water extracts after hydrolysis contained greater amounts of cinnamic acid derivates than those extracts from non-hydrolyzed *** total phenolics content was highest in water extracts of tigerwood, wenge and merbau;however, the extract of merbau wood was a stronger radical scavenger in ABTS?áassays: 34.11 ± 0.02 mM Trolox equivalents per g of dry extract. The main compounds possessing antioxidant activity in the extracts of vermelho wood assessed by UHPLC analysis were hydroxycinnamic acids.

关键词： Phenolic compounds Tropical woods Ultrahigh-performance liquid chromatography Antioxidant capacity

Are genetically distinct lizard species able to hybridize？ A review

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Current Zoology 2015年第1期61卷 155-180页

作者： Jitka JANCUCHOVA-LASKOVA eva LANDOVA Daniel FRYNTA Department of Zoology Faculty of Science Charles University Vini6n~t 7 CZ-128 44 Prague Czech Republic

Animal species are delimited by reproductive isolation mechanisms （RIMs）. Postzygotic RIMs are mainly products of genetic differences and thus their strength increases with elapsed divergence time. The relationship between postzygotic repro- ductive isolation and genetic divergence, however, differs considerably among major clades of vertebrates. We reviewed the available literature providing empirical evidence of natural and/or experimental hybridization between distinct species of lizards （squamates except snakes）. We found that hybridization events are widely distributed among nearly all major lizard clades. The majority of research focuses on parthenogenetic species and/or polyploid hybrids in families Lacertidae, Teiidae and Gekkonidae. Homoploid bisexual hybrids are mainly reported within Lacertidae and Iguania groups. As a proxy of genetic divergence of the hybridizing taxa we adopted nucleotide sequence distance （HKY85） of mitochondrial cyt b gene. The upper limit of genetic di- vergence was similar with regard to both parthenogenetic and bisexual hybrids. Maximum values of these distances between hy- bridizing species of lizards approached 18%-21%, which is comparable to or even exceeds the corresponding values reported for other principal clades of vertebrates. In spite of this, F1 hybrids are typically at least partially fertile in lizards and thus genetic introgression between highly divergent species is possible. The relationship between the genetic distance and hybrid fertility was not found [Current Zoology 61 （1）： 155-180, 2015].

关键词： Hybridization Introgression Fertility Viability Genetic divergence Lizards

Unexpected bonds:ubiquitin-like conjugation of cGAS/CDNTases supports their enzymatic activity and antiphage defense

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Signal Transduction and Targeted Therapy 2023年第9期8卷 3899-3901页

作者： Katarzyna Andryka-Cegielski Sofía Soler eva Bartok Institute of Experimental Haematology and Transfusion Medicine University HospitalUniversity of BonnBonnGermany Institute of Clinical Chemistry and Clinical Pharmacology University HospitalUniversity of BonnBonnGermany

In their recently published study in Nature,Jenson et al.1 provide compelling,unexpected evidence that bacterial cGAMP synthase(cGAS)and other cGAS/DncV-like Nucleotidyltransferases(CD-NTase)undergo ubiquitin-like conjugation(ULC)in type-II cyclic-oligonucleotide-based anti-phage signaling systems(CBASS).cGAS conjugation promotes cyclic-nucleotide(CN)formation and thus antiphage ***,the authors also reveal a new class of phage-encoded CBASS inhibitor,T4 Vs.4,a CN-sponge which limits CBASS effector function and promotes phage replication,revealing another weapon in the“arms race”between phages and their bacterial hosts.

关键词： bonds enzymatic sponge

Determining indoor air quality and identifying the origin of odour episodes in indoor environments

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Journal of Environmental Sciences 2009年第3期21卷 333-339页

作者： eva Gallego Xavier Roca Jose Francisco Perales Xavier Guardino Environmental Centre Laboratory Polytechnic University of Catalonia (LCMA-UPC) Avda Diagonal 647 E 08028 Barcelona Spain National Centre of Work Conditions (INSHT) Dulcet 2-10 E 08034 Barcelona Spain

A methodology for identifying volatile organic compounds （VOCs） and determining air quality of indoor air has been developed. The air samples are collected using pump samplers by the inhabitants when they perceive odorous and/or discomfort episodes. Glass multi-sorbent tubes are connected to the pump samplers for the retention of VOC. The analysis is performed by automatic thermal desorption （ATD） coupled with gas chromatography-mass spectrometry （GC/MS）. This methodology can be applied in cases of sick building syndrome （SBS） evaluation, in which building occupants experience a series of varied symptoms that appear to be linked to time spent in the building. Chemical pollutants concentrations （e.g., VOC） have been described to contribute to SBS. To exemplify the methodology, a qualitative determination and an evaluation of existing VOC were performed in a dwelling where the occupants experienced the SBS symptoms. Higher total VOC （TVOC） levels were detected during episodes in indoor air （1.33 ±1.53 mg/m^3） compared to outdoor air （0.71± 0.46 mg/m^3）. The concentrations of individual VOCs, such as ethanol, acetone, isopropanol, 1-butanol, acetic acid, acetonitrile and 1-methoxy-2-propanol, were also higher than the expected for a standard dwelling. The external source of VOC was found to be an undeclared activity of storage and manipulation of solvents located at the bottom of a contiguous building.

关键词： indoor air thermal desorption TVOC VOC sick building syndrome

Antioxidant efficiency of lycopene on oxidative stress-induced damage in bovine spermatozoa

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Journal of Animal Science and Biotechnology 2017年第1期8卷 67-79页

作者： eva Tvrdá Anton Kovácik eva Tusimová Dusan Paál Alica Mackovich Jakhongir Alimov Norbert Lukác Department of Animal Physiology Faculty of Biotechnology and Food Sciences Slovak University of Agriculture in Nitra Tr. A. Hlinku 2 Nitra 94976 Slovakia AgroBioTech Research Centre Slovak University of Agriculture in Nitra Tr. A. Hlinku 2 Nitra 94976 Slovakia Department of Botany and Genetics Faculty of Natural Sciences Constantine the Philosopher University in Nitra Nabbrezie mladeze 91 Nitra 94974 Slovakia Department of General Biology Faculty of Natural Sciences Gulistan State University 4th Microrayon Guliston 120100 Syrdarya Uzbekistan.

Background： Lycopene（LYC） is a natural carotenoid with powerful reactive oxygen species（ROS） scavenging activities. The aim of this study was to investigate if lycopene has the ability to reverse ROS-mediated alterations to the motility, viability and intracellular antioxidant profile of bovine spermatozoa subjected to ferrous ascorbate（Fe AA）. Spermatozoa were washed out of fresh bovine semen, suspended in 2.9 % sodium citrate and subjected to LYC treatment（0.25, 0.5, 1 or 2 mmol/L） in the presence or absence of Fe AA（150 μmol/L Fe SO4 and 750 μmol/L ascorbic acid） during a 6 h in vitro culture. Spermatozoa motion characteristics were assessed using the Sperm Vision？computer-aided sperm analysis（CASA） system. Cell viability was examined with the metabolic activity（MTT） assay,ROS generation was quantified via luminometry and the nitroblue-tetrazolium（NBT） test was applied to quantify the intracellular superoxide formation. Cell lysates were prepared at the end of the in vitro culture to investigate the intracellular activity of superoxide dismutase（SOD）, catalase（CAT）, glutathione peroxidase（GPx） as well as the concentrations of glutathione（GSH） and malondialdehyde（MDA）.Results： FeA A treatment led to a reduced spermatozoa motility（P 〈 0.001）, viability（P 〈 0.001） and a decline of the antioxidant capacity of spermatozoa（P 〈 0.001） but increased the ROS generation（P 〈 0.001）, superoxide production（P 〈 0.001） and lipid peroxidation（P 〈 0.001）. LYC administration resulted in a preservation of the spermatozoa motion parameters（P 〈 0.001）, mitochondrial activity（P 〈 0.001） and antioxidant characteristics（P 〈 0.001 with respect to SOD;P 〈 0.01 in relation to CAT; P 〈 0.05 as for GPx and GSH） with a concentration range of 1 and 2 mmol/L LYC revealed to be the most ***： Our results suggest that LYC exhibits significant ROS-scavenging and antioxidant properties which may prevent spermatozoa alterations caused by oxidative stress, and preserve the functional

关键词： Antioxidants Bulls Ferrous ascorbate Lycopene Oxidative stress Spermatozoa

Psychological impact of the COVID-19 pandemic on individuals with serious mental disorders: A systematic review of the literature

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World Journal of Psychiatry 2021年第12期11卷 1387-1406页

作者： eva Fleischmann Nina Dalkner Frederike T Fellendorf eva Z Reininghaus Department of Psychiatry and Psychotherapeutic Medicine Medical University of GrazGraz 8036Austria

BACKGROUND The coronavirus disease 2019(COVID-19)pandemic is having a great impact on individuals from all over the world,particularly on individuals with mental *** studies found more pronounced psychiatric symptoms,notably symptoms of depression and *** To assess the situation of patients with serious mental illness(Smi:Affective disorders and schizophrenia)regarding their mental health outcome during the *** A systematic search using the databases PubMed and MEDLINE was conducted,employing the key words“COVID-19”,“SARS-CoV-2”,“psychiatric/mental disorder/illness”,“affective/mood disorder”,“bipolar disorder”,“(major)depression”,“schizoaffective disorder”,and“schizophrenia”.Studies that had been published up until January 9,2021 were *** of studies in languages other than English and German was mostly taken from their English *** The literature search concluded in the finding of 36 studies containing relevant clinical data.A general impairment of the mental health of individuals with Smi could be detected,particularly in individuals with affective disorders,as compared to those with *** to healthy controls,symptoms of anxiety,depression,and stress were more pronounced in individuals with *** factors found that impacted their mental health were age,resilience,and socioeconomic environment,especially the shortage of mental health services,lack of social support,and inadequate information about *** In light of these results,mental health services should be reinforced,notably the use of telemental health ***,supplying individuals with Smi with adequate information about the COVID-19 pandemic and increasing their resilience is *** researching the impact of the COVID-19 pandemic on individuals with Smi,standardization as well as follow-up studies are needed to enable better comparability and understanding.

关键词： COVID-19 pandemic Serious mental illness Affective disorders Bipolar disorder Major depressive disorder Schizophrenia

Structure and Dynamics of the Isoprenoid Pathway Network

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Molecular Plant 2012年第2期5卷 318-333页

作者： eva Vranova Diana Coman Wilhelm Gruissem Department of Biology Plant Biotechnology ETH Zurich Universitatstrasse 2 8092 Zurich Switzerland

Isoprenoids are functionally and structurally the most diverse group of plant metabolites reported to date. They can function as primary metabolites, participating in essential plant cellular processes, and as secondary metabolites, of which many have substantial commercial, pharmacological, and agricultural value. Isoprenoid end products participate in plants in a wide range of physiological processes acting in them both synergistically, such as chlorophyll and carotenoids during photosynthesis, or antagonistically, such as gibberellic acid and abscisic acid during seed germination. It is therefore expected that fluxes via isoprenoid metabolic network are tightly controlled both temporally and spatially, and that this control occurs at different levels of regulation and in an orchestrated manner over the entire isoprenoid metabolic network. In this review, we summarize our current knowledge of the topology of the plant isoprenoid pathway network and its regulation at the gene expression level following diverse stimuli. We conclude by discussing agronomical and biotechnological applications emerging from the plant isoprenoid metabolism and provide an outlook on future directions in the systems analysis of the plant isoprenoid pathway network.

关键词： isoprenoids flux metabolites network pathway.