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Deciphering the role of monosaccharides during phage infection of Staphylococcus aureus

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Nano Research 2022年第10期15卷 9234-9242页

作者： Baptiste Arbez Marion Gardette Christophe Gantzer Neus vilà Isabelle Bertrand Sofiane El-Kirat-Chatel Laboratoire de Chimie Physique et Microbiologie pour les Matériaux et l'Environnement(LCPME) CNRSUniversité de Lorraine405 rue de Vandoeuvre54602 Villers-lès-NancyFrance

As phages are extensively investigated as novel therapy tools but also as transfer agents for antibiotic resistance genes,thorough understanding of phage–host interactions becomes crucial.Prerequisite for phage infection is its adhesion to the host surface.Herein,we used atomic force microscopy-based single-particle force spectroscopy with phage-decorated tips to decipher the adhesion of phage 187 on living Staphylococcus aureus cells.We found that addition of free N-acetyl-Dglucosamine was able to decrease phage adhesion,suggesting that this monosaccharide plays major role in phage 187 infection of S.aureus.Moreover,phage 187 adhesion on monosaccharide-coated model surfaces combined with plaque forming unit counts suggested that a direct link can be established between the propensity to bind to a saccharide and the capability of the latter to inhibit phage infection.On a nanoscale level,single-particle force spectroscopy was successfully used to identify a major receptor required for phage 187 infection of S.aureus but also evidenced that this receptor was responsible for phage adhesion on host-cells.Our work demonstrates that single-particle force spectroscopy is a powerful platform to screen and predict the molecular target of phages on their host surfaces.

关键词： atomic force microscopy single-particle force spectroscopy phage 187 Staphylococcus aureus phage-bacteria interactions

Soil organic carbon stocks and belowground biomass in patches in heterogeneous grassland

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Grassland Research 2023年第4期2卷 279-288页

作者： Martin Komainda Eliana Mohn Klára Kajzrová Kilian Obermeyer Jan Titěra.vilém Pavlů Johannes Isselstein Department of Crop Sciences Grassland ScienceGeorg-August-UniversityGöttingenGermany Faculty of Science Humanities and EducationTechnical University of LiberecLiberecCzechia Department of Agroecology and Crop Production Faculty of AgrobiologyFood and Natural ResourcesCzech University of Life SciencesPrahaCzechia University of Vechta VechtaGermany Grassland Research Station Liberec Department of Weeds and Vegetation of AgroecosystemsCrop Research InstitutePrahaCzechia Centre of Biodiversity and Sustainable Land Use GöttingenGermany

Background:Selective grazing creates stable patches of contrasting sward height,thereby providing different growth conditions for the grass sward above and below ground and potentially affecting soil organic carbon(SOC)stocks.We hypothesized that the presence of patches leads to greater spatial variability in belowground biomass(BGB)and SOC stocks than occurs between pastures managed under different stocking intensities.Methods:A long-term grazing experiment consisting of three stocking intensities was used for this study.We studied BGB,SOC,and soil total nitrogen(Ntot)stocks in the 0-15 cm soil depth.Shannon diversity of plant species,soil bulk density,soil phosphorus,potassium,and magnesium contents were considered.Results:There were no significant effects of patch or stocking intensity on BGB,SOC,and Ntot stocks.Short patches had a greater Shannon diversity than tall patches(p<0.05)and plant-available nutrients in soil correlated positively with sward height(p<0.05).Conclusions:We conclude from the current results and previous studies that higher plant species diversity with lower soil nutrient contents in short-patch areas and higher nutrient contents together with light competition in tall-patch areas might balance each other out with respect to BGB and SOC stocks.

关键词： grazing land roots seminatural grassland soil organic matter stocking rate

Bioactive properties of glycosaminoglycans extracted from Turkey (Meleagris gallopavo) by-products

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Food Bioscience 2022年第2期46卷 321-329页

作者： Evellin Balbinot-Alfaro Claudio R.Novello Elisˆangela Düsman Alexandre T.Alfaro Helyn P.O.Barddal Igor V.Almeida Veronica E.P.Vicentini vil´asia G.Martins School of Chemistry and Food Federal University of Rio GrandeRio GrandeRSBrazil Department of Food Technology Federal University of TechnologyParan´aFrancisco Beltr˜aoPRBrazil Department of Biochemistry and Molecular Biology Federal University of Paran´aCuritibaPRBrazil Federal Rural University of Amazonia Capit˜ao PoçoPABrazil Department of Biotechnology State University of Maring´aMaring´aPRBrazil

Turkey wattle is a by-product generated during slaughter,which has a large amount of connective tissue and is a potential source of glycosaminoglycans(GAGs).This study aimed to extract GAGs from the turkey wattle(Meleagris gallopavos)and investigate its anticoagulant activity,and its cytotoxic and antiproliferative activity in tumor cells.Chondroitin sulfate(CS-4 and CS-6)and dermatan sulfate(DS)present in the F-VII fraction and hyaluronic acid(HA)in the F-V fraction were identified.The HA showed a high molecular weight(1.0×10^(6) Da)and an apparent cytotoxic/antiproliferative effect against human hepatoma cells.F-VII fraction has an apparent cytotoxic/antiproliferative effect against renal adenoma cells and anticoagulant potential in vitro.The results achieved in this study demonstrated that wattle,a by-product of turkey industrialization,has the potential to be valued as a raw material for the extraction of GAGs with bioactive properties.

关键词： Poultry By-products Hyaluronic acid Dermatan sulfate Chondroitin sulfate

Douglas-fi r(Pseudotsuga menziesii(Mirb.)Franco)in Europe:an overview of management practices

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Journal of Forestry Research 2023年第4期34卷 871-888页

作者： Valeriu-Norocel Nicolescu William LMason Jean-Charles Bastien Torsten Vor Krasimira Petkova.vilém Podrázský Martina Đodan Sanja Perić Nicola La Porta Robert Brus Siniša Andrašev Martin Slávik Juraj Modranský Michal Pástor Károly Rédei Branislav Cvjetkovic Ahmet Sivacioğlu Vasyl Lavnyy Cornelia Buzatu-Goanță Gheorghe Mihăilescu Faculty of Silviculture and Forest Engineering Transylvania University of BrasovBrasovRomania Forest Research Northern Research StationRoslinMidlothianUK INRAe Centre Val de Loire ArdonOrléansFrance Faculty of Forest Sciences and Forest Ecology University Georg-AugustGöttingenGermany University of Forestry Sofi aBulgaria Department of Silviculture Faculty of Forestry and Wood SciencesCzech University of Life SciencesPragueCzech Republic Croatian Forest Research Institute JastrebarskoCroatia Foundation Edmund Mach San Michele all’AdigeItaly Biotechnical Faculty University of LjubljanaLjubljanaSlovenia Institute of Lowland Forestry and Environment Novi SadSerbia National Forest Centre Forest Research InstituteZvolenSlovakia Faculty of Ecology and Environmental Sciences Technical University in ZvolenZvolenSlovakia Faculty of Agricultural and Food Sciences and Environmental Management University of DebrecenDebrecenHungary Faculty of Forestry University of Banja LukaBanja LukaBosnia and Herzegovina Department of Silviculture Faculty of ForestryKastamonu UniversityKastamonuTurkey Department of Silviculture Ukrainian National Forestry UniversityLvivUkraine Faculty of Horticulture and Forestry Banat’s University of Agricultural Sciences and Veterinary MedicineTimisoaraRomania Vâlcea County Branch National Forest Administration-ROMSILVARâmnicu-VâlceaRomania

Douglas-fir(Pseudotsuga menziesii(Mirb.)Franco),one of the most commercially important tree species in western North America and one of the most valuable timber trees worldwide,was introduced to Europe in 1827.It became a major species for aff orestation in Western Europe after WWII,currently grows in 35 countries on over 0.83 million ha and is one of the most widespread nonnative tree species across the continent.A lower sensitivity to drought makes Douglas-fi r a potential alternative to the more drought-sensitive Norway spruce so its importance in Europe is expected to increase in the future.It is one of the fastest growing conifer species cultivated in Europe,with the largest reported dimensions of 2.3 m in diameter and 67.5 m in height.Pure stands have high productivity(up to 20 m 3 ha−1 a−1)and production(over 1000 m 3 ha−1).The species is generally regenerated by planting(initial stocking density from less than 1000 seedlings ha−1 to more than 4000 ha−1),using seedlings of European provenance derived from seed orchards or certifi ed seed stands.As the range of end-uses of its wood is very wide,the rotation period of Douglas-fi r is highly variable and ranges between 40 and 120 years.When the production of large-sized,knotfree timber is targeted,thinnings are always coupled with pruning up to 6 m.There is an increasing interest in growing Douglas-fi r in mixtures and managing stands through close-to-nature silviculture,but the species’intermediate shade tolerance means that it is best managed through group selection or shelterwood systems.

关键词： Douglas-fi r Ecological requirements Growth and yield Timber Climate change

Nervous System and Gastrointestinal Effects of the Insecticide Esfenvalerate on the Rat:An Ex Vivo Study

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Agricultural Sciences 2014年第4期5卷 365-375页

作者： Petra Varró Eszter Szabó Melinda Kovács Ildikó világi Department of Physiology and Neurobiology Eotvos Loránd UniversityBudapestHungary MTA-KE Mycotoxins in the Food Chain Research Group KaposvárHungary

Esfenvalerate belongs to the pyrethroid group of insecticides which display significant selective toxicity against insects compared to mammalian species, nevertheless, they may pose health risks, especially in case of accidental exposure. The aim of the present study was to model the effect of acute, relatively high-dose exposure of the esfenvalerate-containing formulation Sumi-Alpha?. Eventual functional alterations in the central nervous system and in the gastrointestinal tract were studied on in vitro tissue preparations at different delays after intragastric administration to rats. Neuronal effects were characterized by field potential recording in cortical and hippocampal brain slices, while gastrointestinal effects were examined by analyzing the motility and excitability of isolated ileum segments. On the brain slices originating from esfenvalerate-treated animals, changes in excitability of both inhibitory and excitatory type could be observed. Voltage thresholds necessary to evoke responses in neocortex slices were elevated, and population spike amplitudes were lower in hippocampal slices. However, epileptiform potentials with pronounced late components were also observed. A decreased long-term potentiation (LTP) could be seen in both brain areas after esfenvalerate treatment. Seizure susceptibility of the slices was not significantly altered, but tended to be somewhat higher in slices originating from treated rats. In ileum segments, both spontaneous and acetyl-choline (ACh)-elicited contractions were modified by treatment. Esfenvalerate raised the amplitude of contractions in the low ACh concentration range. However, the solvent xylene also considerably contributed to the detected changes. We can conclude that a relatively high, single oral dose of Sumi-Alpha? exerted mild and temporary effects on the elementary brain functions and intestine functions of the rat.

关键词： Pyrethroid Ileum Motility Brain Slice Field Potentials

“电子政府”和信息系统在美国地方政府管理中的应用

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政治学研究 2005年第1期 120-127页

作者：吴量福 vil.dowerns-grove.il.us) 美国丹尼森市信息部(E-mail:lwu

信息系统在美国地方政府管理中的应用经历前互联网和互联网两个时期,主要应用于财政管理、人事管理、土地管理、公共安全、市政工程等,改善了这些领域的服务。“地理信息系统”的出现和利用提高了工作效率,并逐渐成为公共管理领域的操... 详细信息

信息系统在美国地方政府管理中的应用经历前互联网和互联网两个时期,主要应用于财政管理、人事管理、土地管理、公共安全、市政工程等,改善了这些领域的服务。“地理信息系统”的出现和利用提高了工作效率,并逐渐成为公共管理领域的操作平台与支持决策工具。电子政府是指建立在信息技术上的政府运作过程,是高效率的政府过程。改进政府的运作程序是电子政府的实质所在。网络化和政府网络仅仅是电子政府内容的一部分,电子政府效果量化,这是目前值得研究的两个问题。

关键词：地方政府管理 “电子政府” 应用美国地理信息系统财政管理人事管理土地管理公共安全市政工程工作效率决策工具操作平台管理领域运作过程信息技术运作程序政府网络互联网高效率网络化

Levamisole-Adultered Cocaine: Vasoconstrictive and Vasculitis Effects Occurring Simultaneously

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Case Reports in Clinical Medicine 2022年第5期11卷 167-174页

作者： María A. Rodríguez-Santiago Hillarie Ríos-Torres Giulianni Oliveras-Maldonado Valeria Martinez-Lebrón Suheiry Márquez-Márquez Adianez Santiago-Santiago Salvador vilá-Pérez Marcel Mesa-Pabón Department of Internal Medicine School of Medicine University of Puerto Rico San Juan Puerto Rico

This case presents a rarely seen combination of two Cocaine-induced syndromes occurring simultaneously. Levamisole-adultered cocaine leads to Levamisole-induced Vasculitis (LIV), while cocaine’s vasoconstrictive effect causes destruction of the osteo-cartilaginous structures of nose called Cocaine-induced midline destructive lesions (CIMDL). This case raises awareness of a new pattern of recognition in order to avoid misdiagnosis. We present a case of a 51-year-old male cocaine user who developed severe left-sided ear pain and yellowish secretions with circular necrotic lesions in the nose, right earlobe, and dorsum of feet bilaterally. An extensive workup to assess purpuric lesions’ etiology, including vasculitis, collagen vasculitides, anti-phospholipid syndrome, hypercoagulable state and infectious process, was performed and found negative. He developed bilateral tympanic membrane perforation and purpuric necrotic skin lesions, at the same time, due to CIMDL and LIV, respectively. These two syndromes rarely present simultaneously in a patient. This case report exhibits a new Cocaine-induced clinical presentation that will help hospitalists recognize the disease and avoid misdiagnosis leading to unnecessary tests, prolonged hospitalization, and higher healthcare costs. Diagnosis is challenging, as it consists of establishing a temporal relationship between cocaine ingestion and symptoms’ onset. This disease usually has a benign progression because symptoms frequently resolve without intervention.

关键词： Levamisole-Induced Vasculitis Cocaine-Induced Midline Destructive Lesions Cocaine’s Side Effect Spectrum

Establishing the Tolerability to Turkeys of Nonanoic Acid at Practical Levels of Use as a Feed Flavoring

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Open Journal of Animal Sciences 2021年第3期11卷 422-439页

作者： Maria H. L. Bento Elizabeth A. Lewis Miquel Nofrarias Borja.vilà Philip McGuire Kurt Richardson NutraSteward Pembroke Dock UK CReSA—Animal Health IRTA Bellaterra Spain Animal Nutrition IRTA Constantí Spain Anitox Wellingborough UK

Objective: Nonanoic acid (NA) is one of a series of straight-chain aliphatic alcohols, aldehydes, acids and their derivatives with a well-documented history of use as a synthetic flavoring in human food. As part of a safety evaluation of NA for use as a flavoring in animal feed, an experiment was conducted to evaluate the ability of turkeys to tolerate NA at levels relevant to practical feeding practices. Materials and Methods: A total of 594-day-old BUT Premium turkeys (300 males and 294 females) were allocated at random to 40 floor pens containing either 15 males or 13 to 15 females. Poults were fed one of 4 treatment diets in crumble (0 to 14 days) or pellet (15 to 59 days) form containing 0 (control), 100, 300 or 1000 mg NA/kg complete feed for 59 days. General health and performance were monitored for the duration of the study. At days 57 and 59 of age, blood samples were taken and birds were sacrificed and necropsied for histopathological examination of the digestive tract. Significant differences were considered at P ≤ 0.05 and near-significant trends at P ≤ 0.10.

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由酸性硫酸铜镀浴进行脉冲选择镀

电刷镀技术 1989年第1期 51-53页

作者： vil.,NRK 张孝仁