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Individual stages of bacterial dichloromethane degradation mapped by carbon and chlorine stable isotope analysis

Journal of Environmental Sciences 2019年第4期31卷 147-160页

作者： maria l.torgonskaya Anatoly M.Zyakun Yuri A.Trotsenko Kestutis S.laurinavichius Steffen Kümmel Stéphane Vuilleumier Hans H.Richnow laboratory of Radioactive Isotopes G.K.Skryabin Institute of Biochemistry and Physiology of MicroorganismsFRC Pushchino Center for Biological ResearchRussian Academy of Sciences laboratory of Mass Spectrometry G.K.Skryabin Institute of Biochemistry and Physiology of MicroorganismsFRC Pushchino Center for Biological ResearchRussian Academy of Sciences Department of Isotope Biogeochemistry Helmholtz Centre for Environmental Research-UFZ Université de Strasbourg CNRS

The fractionation of carbon and chlorine stable isotopes of dichloromethane(CH_2Cl_2,DCM)upon dechlorination by cells of the aerobic methylotroph Methylobacterium extorquens DM4 and by purified DCM dehalogenases of the glutathione S-transferase family was analyzed.Isotope effects for individual steps of the multi-stage DCM degradation process,including transfer across the cell wall from the aqueous medium to the cell cytoplasm,dehalogenase binding,and catalytic reaction,were considered.The observed carbon and chlorine isotope fractionation accompanying DCM consumption by cell supensions and enzymes was mainly determined by the breaking of C\Cl bonds,and not by inflow of DCM into cells.Chlorine isotope effects of DCM dehalogenation were initially masked in high density cultures,presumably due to inverse isotope effects of non-specific DCM oxidation under conditions of oxygen excess.Glutathione cofactor supply remarkably affected the correlation of variations of DCM carbon and chlorine stable isotopes(Δδ^(13)C/Δδ^(37)Cl),increasing corresponding ratio from 7.2–8.6 to 9.6–10.5 under conditions of glutathione deficiency.This suggests that enzymatic reaction of DCM with glutathione thiolate may involve stepwise breaking and making of bonds with the carbon atom of DCM,unlike the uncatalyzed reaction,which is a one-stage process,as shown by quantum-chemical modeling.

关键词： Dichloromethane(DCM) Microbial degradation Aerobic methylotrophic bacteria Dichloromethane dehalogenase Carbon and chlorine isotopic fractionation

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Integration of multiple flexible electrodes for realtime detection of barrier formation with spatial resolution in a gut-on-chip system

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Microsystems & Nanoengineering 2024年第1期10卷 105-114页

作者： Mara lucchetti Gabriel Werr Sofia Johansson laurent Barbe léa Grandmougin Paul Wilmes maria Tenje luxembourg Centre for Systems Biomedicine(lCSB) University of LuxembourgEsch-sur-Alzette L-4362Luxembourg Division of Biomedical Engineering Department of Materials Science and EngineeringScience for Life LaboratoryUppsala University75121 UppsalaSweden Department of life Sciences and Medicine Faculty of ScienceTechnology and MedicineUniversity of LuxembourgEsch-sur-Alzette L-4362Luxembourg

In healthy individuals,the intestinal epithelium forms a tight barrier to prevent gut bacteria from reaching blood circulation.To study the effect of probiotics,dietary compounds and drugs on gut barrier formation and disruption,human gut epithelial and bacterial cells can be cocultured in an in vitro model called the human microbial crosstalk(HuMiX)gut-on-a-chip system.Here,we present the design,fabrication and integration of thin-film electrodes into the HuMiX platform to measure transepithelial electrical resistance(TEER)as a direct readout on barrier tightness in realtime.As various aspects of the HuMiX platform have already been set in their design,such as multiple compressible layers,uneven surfaces and nontransparent materials,a novel fabrication method was developed whereby thin-film metal electrodes were first deposited on flexible substrates and sequentially integrated with the HuMiX system via a transfer-tape approach.Moreover,to measure localized TEER along the cell culture chamber,we integrated multiple electrodes that were connected to an impedance analyzer via a multiplexer.We further developed a dynamic normalization method because the active measurement area depends on the measured TEER levels.The fabrication process and system setup can be applicable to other barrier-on-chip systems.As a proof-of-concept,we measured the barrier formation of a cancerous Caco-2 cell line in real-time,which was mapped at four spatially separated positions along the HuMiX culture area.

关键词： barrier system multiple

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Biodegradability of bioplastics in different aquatic environments:A systematic review

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Journal of Environmental Sciences 2024年第8期142卷 169-181页

作者： maria Cristina lavagnolo Valentina Poli Anna maria Zampini Valentina Grossule Department of Civil Environmental and Architectural Engineering-Laboratory of Environmental EngineeringUniversity of PadovaLungargine Rovetta 8Padova 35100Italy

Bioplastics were first introduced as environmentally friendly materials,with properties similar to those of conventional plastics.A bioplastic is defined as biodegradable if it can be decomposed into carbon dioxide under aerobic degradation,or methane and CO_(2)under anaerobic conditions,inorganic compounds,and new cellular biomass,by the action of naturally occurring microorganisms.This definition however does not provide any information on the environmental conditions,timescale and extent at which decomposition processes should occur.With regard to the aquatic environment,recognized standards have been established to assess the ability of plastics to undergo biodegradation;however,these standards fail to provide clear targets to be met to allow labelling of a bioplastic as biodegradable.Moreover,these standards grant the user an extensive leeway in the choice of process parameters.For these reasons,the comparison of results deriving from different studies is challenging.The authors analysed and discussed the degree of biodegradability of a series of biodegradable bioplastics in aquatic environments(both fresh and salt water)using the results obtained in the laboratory and from on-site testing in the context of different research studies.Biochemical Oxygen Demand(BOD),CO_(2)evolution,surface erosion and weight loss were the main parameters used by researchers to describe the percentage of biodegradation.The results showed a large variability both in weight loss and BOD,even when evaluating the same type of bioplastics.This confirms the need for a reference range of values to be established with regard to parameters applied in defining the biodegradability of bioplastics.

关键词： Biodegradation Bioplastic Plastic Natural environment Plastic waste

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History of chronic gastritis:How our perceptions have changed

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World Journal of Gastroenterology 2024年第13期30卷 1851-1858页

作者： Dmitry Bordin maria livzan Department of Pancreatic Biliary and Upper GI Tract DiseasesA.S.Loginov Moscow Clinical Scientific CenterMoscow 111123Russia Department of Propaedeutic of Internal Diseases and Gastroenterology Russian University of MedicineMoscow 127006Russia Department of Outpatient Therapy and Family Medicine Tver State Medical UniversityTver 170100Russia Department of Internal Medicine and Gastroenterology Omsk State Medical UniversityOmsk 644099Russia

Currently,the diagnostic strategy for chronic gastritis(CG)is aimed not just at fixing the presence of gastric mucosal inflammation,but also at gastric cancer(GC)risk stratification in a particular patient.Modern classification approach with the definition of the stage of gastritis determines the need,activities and frequency of dynamic monitoring of a patient.However,this attitude to the patient suffering from CG was far from always.The present publication is a literature review describing the key milestones in the history of CG research,from the description of the first observations of inflammation of the gastric mucosa,assessment of gastritis as a predominantly functional disease,to the advent of endoscopy of the upper digestive tract and diagnostic gastric biopsy,assessment of the role of Helicobacter pylori infection in progression of inflammatory changes to atrophy,intestinal metaplasia,dysplasia and GC.

关键词： Chronic gastritis Intestinal metaplasia Dysplasia Gastric cancer Helicobacter pylori

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Effect of low concentration electrolytes on the formation and corrosion resistance of PEO coatings on AM50 magnesium alloy

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Journal of Magnesium and Alloys 2024年第4期12卷 1386-1405页

作者： Peng Xie Carsten Blawert maria Serdechnova Natalia Konchakova Tatsiana Shulha Ting Wu Mikhail l.Zheludkevich Institute of Surface Science Helmholtz-Zentrum HereonMax-Planck Strasse 121502 GeesthachtGermany Institute for Materials Science Faculty of EngineeringKiel UniversityKaiserstrasse 224143 KielGermany

In this paper,the formation process,morphology,and electrochemical performance of PEO coatings on AM50 magnesium alloy prepared in low concentration phosphate,aluminate,and phosphate-aluminate electrolytes were systematically studied.The results show that the coatings prepared from the phosphate electrolytes have a higher thickness and better corrosion resistance properties compared to the other electrolytes.The coatings prepared from low concentration phosphate-aluminate mixed electrolytes have slightly thinner thickness,a similar coating structure and an order of magnitude lower value of electrochemical impedance compared with phosphate electrolyte coatings.The Coatings prepared from low concentration aluminate electrolytes have the lowest thickness and the worst corrosion resistance properties which gets close to corrosion behavior of the bare AM50 under the same test conditions.Considering application,coatings prepared from single low concentration phosphate electrolytes and low concentration phosphate-aluminate electrolytes have greater potential than single low concentration aluminate coatings.However,reducing the electrolyte concentrations of coating forming ions too much has negative influence on the coating growth rate.

关键词： Plasma electrolytic oxidation low concentration electrolytes Corrosion resistance AM50 magnesium alloy

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Tocotrienol isoforms:The molecular mechanisms underlying their effects in cancer therapy and their implementation in clinical trials

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Journal of Integrative Medicine 2024年第1期22卷 1-11页

作者： maria Younes Ghady loubnane Christopher Sleiman Sandra Rizk Department of Natural Sciences Lebanese American UniversityByblosLebanon

Tocotrienols are found in a variety of natural sources,like rice bran,annatto seeds and palm oil,and have been shown to have several health-promoting properties,particularly against chronic diseases such as cancer.The incidence of cancer is rapidly increasing around the world,not only a result of continued aging and population growth,but also due to the adoption of aspects of the Western lifestyle,such as high-fat diets and low-physical activity.The literature provides strong evidence that tocotrienols are able to inhibit the growth of various cancers,including breast,lung,ovarian,prostate,liver,brain,colon,myeloma and pancreatic cancers.These findings,along with the reported safety profile of tocotrienols in healthy human volunteers,encourage further research into these compounds’potential use in cancer prevention and treatment.The current review provided detailed information about the molecular mechanisms of action of different tocotrienol isoforms in various cancer models and evaluated the potential therapeutic effects of different vitamin E analogues on important cancer hallmarks,such as cellular proliferation,apoptosis,angiogenesis and metastasis.MEDlINE/PubMed and Scopus databases were used to identify recently published articles that investigated the anticancer effects of vitamin E derivatives in various types of cancer in vitro and in vivo along with clinical evidence of adjuvant chemopreventive benefits.Following an overview of pre-clinical studies,we describe several completed and ongoing clinical trials that are paving the way for the successful implementation of tocotrienols in cancer chemotherapy.

关键词： Vitamin E Tocotrienols Cancer Molecular mechanism Clinical trials

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Outpatient management of obscure gastrointestinal bleeding:A new perspective in high-risk patients

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World Journal of Gastroenterology 2024年第19期30卷 2502-2504页

作者： maria Elena Riccioni Clelia Marmo Digestive Endoscopy Unit Fondazione Policlinico Universitario Agostino GemelliIRCCSUniversitàCattolica del Sacro CuoreLargo Agostino GemelliRome 00168Italy CEMAD Centro Malattie Dell’Apparato Digerente Fondazione Policlinico Universitario Agostino GemelliIRCCSUniversitàCattolica del Sacro CuoreLargo Agostino GemelliRome 00168Italy

Mid-gastrointestinal bleeding accounts for approximately 5%-10%of all gastrointestinal bleeding cases,and vascular lesions represent the most frequent cause.The rebleeding rate for these lesions is quite high(about 42%).We hereby recommend that scheduled outpatient management of these patients could reduce the risk of rebleeding episodes.

关键词： Gastrointestinal bleeding Small bowel bleeding Recurrent bleeding Rebleeding risk Rebleeding Outpatient management

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Indocyanine green:The guide to safer and more effective surgery

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 641-649页

作者： Pietro Fransvea maria Michela Chiarello Valeria Fico maria Cariati Giuseppe Brisinda Emergency Surgery and Trauma Center Fondazione Policlinico Universitario Agostino Gemelli IRCCSRome 00168Italy Department of Surgery Azienda Sanitaria Provinciale di CosenzaCosenza 87100Italy Department of Surgery Azienda Sanitaria Provinciale di CrotoneCrotone 88900Italy Department of Abdominal and Endocrine Metabolic Medical and Surgical Sciences Fondazione Policlinico Universitario A Gemelli IRCCSRome 00168Italy

In this editorial we comment on the article by Kalayarasan and co-workers published in the recent issue of the World Journal of Gastrointestinal Surgery.The authors present an interesting review on the use of indocyanine green fluo-rescence in different aspects of abdominal surgery.They also highlight future perspectives of the use of indocyanine green in mini-invasive surgery.Indo-cyanine green,used for fluorescence imaging,has been approved by the Food and Drug Administration and is safe for use in humans.It can be administered in-travenously or intra-arterially.Since its advent,there have been several advance-ments in the applications of indocyanine green,especially in the surgical field,such as intraoperative mapping and biopsy of sentinel lymph node,measurement of hepatic function prior to resection,in neurosurgical cases to detect vascular anomalies,in cardiovascular cases for patency and assessment of vascular ab-normalities,in predicting healing following amputations,in helping visualization of hepatobiliary anatomy and blood vessels,in reconstructive surgery,to assess flap viability and for the evaluation of tissue perfusion following major trauma and burns.For these reasons,the intraoperative use of indocyanine green has become common in a variety of surgical specialties and transplant surgery.Co-lorectal surgery has just lately begun to adopt this technique,particularly for perfusion visualization to prevent anastomotic leakage.The regular use of in-docyanine green coupled with fluorescence angiography has recently been pro-posed as a feasible tool to help improve patient outcomes.Using the best available data,it has been shown that routine use of indocyanine green in colorectal surgery reduces the rates of anastomotic leak.The use of indocyanine green is proven to be safe,feasible,and effective in both elective and emergency scenarios.However,additional robust evidence from larger-scale,high-quality studies is essential before incorporating indocyanine green guided surgery into standard practice.

关键词： Indocyanine green Colorectal surgery Fluorescence-guided surgery Gastrointestinal surgery Hepato-biliary surgery Pancreatic surgery Surgical oncology

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Shear-wave elastography to predict hepatocellular carcinoma after hepatitis C virus eradication:A systematic review and meta-analysis

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World Journal of Gastroenterology 2024年第10期30卷 1450-1460页

作者： Giorgio Esposto Paolo Santini linda Galasso Irene Mignini maria Elena Ainora Antonio Gasbarrini maria Assunta Zocco CEMAD Digestive Disease Center Fondazione Policlinico Universitario“A.Gemelli”IRCCSCatholic University of RomeRome 00168Italy Fondazione Policlinico Universitario Agostino Gemelli IRCCS Fondazione Policlinico Universitario Agostino Gemelli IRCCS-UniversitàCattolica del Sacro CuoreRome 00168Italy Medicina Interna e Gastroenterologia CEMAD Digestive Disease CenterUniversitàCattolica del Sacro CuoreFondazione Policlinico Universitario A Gemelli IRCCSRome 00168Italy

BACKGROUND Direct-acting antiviral agents(DAAs)are highly effective treatment for chronic hepatitis C(CHC)with a significant rate of sustained virologic response(SVR).The achievement of SVR is crucial to prevent additional liver damage and slow down fibrosis progression.The assessment of fibrosis degree can be performed with transient elastography,magnetic resonance elastography or shear-wave elastography(SWE).liver elastography could function as a predictor for hepato-cellular carcinoma(HCC)in CHC patients treated with DAAs.AIM To explore the predictive value of SWE for HCC development after complete clearance of hepatitis C virus(HCV).METHODS A comprehensive literature search of clinical studies was performed to identify the ability of SWE to predict HCC occurrence after HCV clearance.In accordance with the study protocol,a qualitative and quantitative analysis of the evidence was planned.RESUlTS At baseline and after 12 wk of follow-up,a trend was shown towards greater liver stiffness(lS)in those who go on to develop HCC compared to those who do not[baseline lS standardized mean difference(SMD):1.15,95%confidence interval(95%CI):020-2.50;lS SMD after 12 wk:0.83,95%CI:0.33-1.98].The absence of a statistically significant difference between the mean lS in those who developed HCC or not may be related to the inability to correct for confounding factors and the absence of raw source data.There was a statist-ically significant lS SMD at 24 wk of follow-up between patients who developed HCC vs not(0.64;95%CI:0.04-1.24).CONClUSION SWE could be a promising tool for prediction of HCC occurrence in patients treated with DAAs.Further studies with larger cohorts and standardized timing of elastographic evaluation are needed to confirm these data.

关键词： Shear-wave elastography Hepatocellular carcinoma Hepatitis C virus Sustained virologic response

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Carbon sequestration in a bamboo plantation:a case study in a Mediterranean area

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Journal of Forestry Research 2024年第3期35卷 231-238页

作者： Tommaso Chiti Emanuele Blasi maria Vincenza Chiriaco Department for Innovation in Biological Agro-Food and Forest Systems(DIBAF)University of TusciaVia San C.De Lellis snc01100 ViterboItaly Foundation Euro-Mediterranean Center on Climate Change(CMCC) Division on Climate Change Impacts on AgricultureForests and Ecosystem Services(IAFES)Via Garbini5101100 ViterboItaly

In the Mediterranean region,despite bamboo being an alien species that can seriously alter plant and ani-mal biocoenosis,the area occupied by bamboo plantations continues to increase,especially for the purpose to seques-ter carbon(C).However,the C dynamics in the soil-plant system when bamboo is grown outside its native area are poorly understood.Here we investigated the C mitigation potential of the fast-growing Moso bamboo(Phyllostachys edulis)introduced in Italy for climate-change mitigation.We analyzed aboveground(AGB)and belowground(as root/shoot ratio)biomass,litter and soil organic C(SOC)at O-15-and 15-30-cm depths in a 4-year-old bamboo plantation in comparison with the former annual cropland on which the bamboo was established.To have an idea of the maximum C stored at an ecosystem level,a natural forest adjacent the two sites was also considered.In the plantation,C accumulation as AGB was stimulated,with 14.8±3.1 Mg C ha^(-1) stored in 3 years;because thinning was done to remove culms from the first year,the mean sequestration rate was 4.9 Mg C ha^(-1) a^(-1).The sequestration rates were high but comparable to other fast-growing tree species in Italy(e.g.,Pinus nigra).SOC was significantly higher in the bamboo plantation than in the cropland only at the 0-15 cm depth,but SOC stock did not differ.Possibly 4 years were not enough time for a clear increase in SOC,or the high nutrient uptake by bamboos might have depleted the soil nutrients,thus inhibiting the soil organic matter formation by bacteria.In comparison,the natural forest had significantly higher C levels in all the pools.For C dynamics at an ecosystem level,the bamboo plantation on the former annual cropland led to substantial C removal from the atmosphere(about 12 Mg C ha^(-1) a^(-1)).However,despite the promising C sequestration rates by bamboo,its introduction should be carefully considered due to potential ecological problems caused by this species in overexploited environments such as the Mediterranean area.

关键词： Carbon sequestration Climate change mitigation Mediterranean area Moso bamboo Soil organic carbon

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