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High Resolution Mass Spectrometry for the Recognition and Structural Characterization of a New Antimicrobial Compound

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Pharmacology & Pharmacy 2018年第5期9卷 135-148页

作者： lù cia carrano Annamaria Naggi Elena Urso Fondazione Istituto Insubrico Ricerca per la Vita Gerenzano Italy Istituto di Ricerche Chimiche e Biochimiche G. Ronzoni Milan Italy

Identification of novel specialized metabolites or bioactive compounds represents the main objective in the research field of natural product leads and drug discovery. Mass spectrometry (MS) provides a central tool to expedite and make more efficient the discovery and isolation phases, while minimizing the waste of resources on rediscovery of known compounds. MS contributes acutely to elucidation and identification of numerous species because it allows molecular mass and structural features determination. In particular, identification of the elemental composition of a precursor ion of interest by accurate mass measurement and investigation of dissociative processes undergone by the molecule, represent a worthy methodology to access the structure assignment. The aim of this study was to discover and identify novel antibacterial drugs from microbial source in a jungle of already known compounds. The focus of this paper is on the analytical strategy that permitted the disclosure of a new compound, otherwise confused with other substances. Emphasis is placed on the interpretation of the ESI-MS/MS fragmentation pattern that combined with high resolution mass determination, allowed step by step to properly deduce the exact molecular formula of an unknown component with a molecular weight higher than 1500 Daltons.

关键词： Antibiotic Development Antibiotic Discovery High Resolution Mass Spectrometry Molecular Formula MS/MS Fragmentation FT ICR MS

Implications of Withaferin A in neurological disorders

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Neural Regeneration Research 2021年第2期16卷 304-305页

作者： Natasha Ram Stephanie l.Peak andres R.Perez Umesh K.Jinwal Department of Pharmaceutical Sciences Taneja College of PharmacyUniversity of South FloridaTampaFLUSA

Extract from the medicinal herb Withania somnifera(WS),commonly known as Ashwagandha,has therapeutic implications in various conditions such as infection,inflammation,cancer,stress,neurodegenerative diseases,heart dis... 详细信息

关键词： inflammation diseases infection

An evaluation of mass,number concentration,chemical composition and types of particles in a cafeteria before and after the passage of an antismoking law

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Particuology 2013年第5期11卷 527-532页

作者： Jorge Pey Barend l.van Drooge Anna Ripollb Teresa Moreno Joan O.Grimalt Xavier Querol andres Alastuey Department of Epidemiology Lazio Regionvia S.Costanza5300198 RomeItaly Institute of Environmental Assessment and Water Research.ID/EA-CSIC C/Jordi Girona.18-2608034 BarcelonaSpain

This study assessed air quality indicators before and after enactment of the Spanish anti-smoking law. Mass and number concentrations and the chemical composition of particles were evaluated. Microscopy analyses were also conducted. Real time concentrations of PMlo, PM2.s, PM1 and ultrafine particles were measured under ventilated and non-ventilated conditions and PMlo samples were collected for detailed inorganic and organic chemical characterization. Before enactment of the law in 2010, tobacco smoke produced significant indoor ambient particulate matter pollution, with elevated particulate matter mass concentrations （PM10 and PM1 concentrations of 122-220 and 48-85 Dg/m3, respectively） and ultrafine particle numbers （75,000 and 48,000 cm ~ under ventilated and non-ventilated conditions, respectively）. Typical tobacco smoke tracers including iso- and anteiso-alkanes and elements including la and Ce from the ignition of lighters were abundant. Additionally, several toxic substances derived from tobacco smoke, including Cd （3.1 ng/m3） and benzo[a]pyrene （1.0 ng/m3） were present at concentrations approximately 10 times greater than those measured after enactment of the anti-smoking law. The anti-smoking law sig- nificantly reduced exposure to potentially toxic compounds by approximately 90%. This law is expected to have a positive health impact, particularly for people who spend considerable time in affected envi- ronments, such as employees.

关键词： Indoor airParticulate matterUltrafine particlesNucleationCoagulation-condensationEnvironmental tobacco smoke

Strain engineering in single-,bi-and tri-layer MoS_(2),MoSe_(2),WS_(2)and WSe_(2)

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Nano Research 2021年第6期14卷 1698-1703页

作者： Felix Carrascoso Hao li Riccardo Frisenda andres Castellanos-Gomez Materials Science Factory Instituto de Ciencia de Materiales de MadridConsejo Superior de Investigaciones Cientificas28049MadridSpain

Strain is a powerful tool to modify the optical properties of semiconducting transition metal dichalcogenides like MoS_(2),MoSe_(2),WS_(2) and WSe_(2).In this work we provide a thorough description of the technical details to perform uniaxial strain measurements on these two-dimensional semiconductors and we provide a straightforward calibration method to determine the amount of applied strain with high *** then employ reflectance spectroscopy to analyze the strain tunability of the electronic properties of single-,bi-and tri-layer MoS_(2),MoSe_(2),WS_(2) and WSe_(2).Finally,we quantify the flake-to-flake variability by analyzing 15 different single-layer MoS_(2) flakes.

关键词： two-dimensional(2D)materials transition metal dichalcogenides strain engineering band gap differential reflectance

Payenia Quaternary flood basalts(southern Mendoza, Argentina)：Geophysical constraints on their volume

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Geoscience Frontiers 2016年第5期7卷 775-782页

作者： Mauro G.Spagnuolo Darío l.Orts Mario Gimenez andres Folguera Victor A.Ramos Instituto de Estudios Andinos Don Pablo Groeber (I DEAN) UBA-CONICET Argentina Instituto de Investigacion en Paleobiologia y Geologia Universidad Nacional de Rio Negro - CONICET Argentina Instituto Geofisico y Sismologico Ing. Volponi Universidad Nacional de San Juan. CONICET Argentina

The Quaternary volcanic province of Payenia is located in southern Mendoza and northern Neuquén provinces of Argentina and is characterized by a dominant basaltic composition. The volcanic province covers an area larger than 40,000 km2 and its origin and evolution has been the center of several *** this study we analyzed gravity data together with more accurate volcanic volumes calculations in order to investigate the subsurface structure of the Payenia volcanic province. The volume of material was calculated using digital elevation models and geographic information system（GIS） techniques to estimate the volume of material erupted and then, with those values, make an estimation of the intrusive material that could be located within the crust. The results of the calculations were compared with different 2D-sections constructed to model the gravity data and compare with the observed satellite gravity. After evaluating different models which have been generated to match both： the observed gravity data and the subsurface material calculated, we discuss those that best fit with observation. The results clearly indicate that the lithosphere is attenuated below the region.

关键词： Payenia Gravimetric model Plume Uplift Andes

limb preservation with suprafascial and thin perforator flaps: salvaging osteomyelitis, Charcot collapse and critical limb ischemia

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Plastic and Aesthetic Research 2019年第8期6卷 13-23页

作者： Shawn Diamond andres F.Doval Benjamin Scott Matthew l.Iorio Division of Plastic and Reconstructive Surgery Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMA 02215USA Division of Plastic and Reconstructive Surgery University of Colorado Anschutz Medical CenterAuroraCO 80045USA.

AIM: There are limited reports in the United States demonstrating outcomes of primarily thinned fasciocutaneous flaps in the setting of critical limb ischemia, Charcot collapse and osteomyelitis. We hope to determine patient and flap related outcomes in advanced lower extremity disease. Methods: The authors conducted a retrospective review of fasciocutaneous free flaps of variable thickness for lower extremity salvage. Osteomyelitis and non-osteomyelitis patients were compared according to our primary outcome measures: functional ambulation, bone healing and complications to flap and patient. Subgroups with critical limb ischemia, Charcot collapse and diabetic foot were analyzed separately. Results: Fifty-nine patients underwent free flap reconstruction: osteomyelitis (n = 20, 34%), Charcot collapse (n = 22, 37%), and/or critical limb ischemia (n = 12, 20%). All patients underwent anterolateral thigh flaps tailored for defect-specific thicknesses: 17 superthin, 25 suprafascial, 17 subfascial. There were no significant differences between groups in terms of partial and complete flap loss (P = 1.000 and P = 0.108). Ninety-one percent of patients were ambulatory at follow up. Eighty-tive percent of individuals with osteomyelitis cleared their infection demonstrating radiographic bone healing. Two patients developed recalcitrant deep space infections ultimately requiring amputation. Subgroup analysis did not show any differences in flap related complications within the diabetic Charcot population. In multivariate regression, preoperative revascularization was independently associated with failure of limb salvage. ;Conclusion: Primarily thinned perforator flaps performed well in the setting of lower extremity limb salvage, critical limbischemia, osteomyelitis, and the Charcot foot - expanding their role in the armamentarium for lower extremity care.

关键词： Perforator flap diabetic foot limb salvage

Systematic determination of a material’s magnetic ground state from first principles

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npj Computational Materials 2024年第1期10卷 3036-3045页

作者： andres Tellez-Mora Xu He Eric Bousquet ludger Wirtz Aldo H.Romero Department of Physics and Astronomy West Virginia UniversityMorgantownWV 26505-6315USA Physique Théorique des Matériaux QMATCESAMUniversitéde LiègeB-4000 Sart-TilmanBelgium Physics and Materials Science Research Unit University of Luxembourg162a avenue de la FaïencerieL-1511 LuxembourgLuxembourg

We present a self-consistent method based on first-principles calculations to determine the magnetic ground state of materials,regardless of their *** methodology is founded on satisfying the stability conditions derived from the linear spin wave theory(lSWT)by optimizing the magnetic structure *** demonstrate the effectiveness of our method by successfully predicting the experimental magnetic structures of Ni_(O),FePS_(3),FeP,MnF_(2),FeCl_(2),and Cu_(O).In each case,we compared our results with available experimental data and existing theoretical calculations reported in the ***,we discuss the validity of the method and the possible extensions.

关键词： magnetic state ground

Hyponatraemia and cirrhosis

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Gastroenterology Report 2014年第1期2卷 21-26页

作者： Robert J.Gianotti andres Cardenas Department of Gastroenterology Beth Israel Deaconess Medical CenterBoston MA GI Unit Institut Clinic de Malalties Digestives i MetaboliquesHospital ClinicUniversity of Barcelona

Hyponatraemia is a common complication of advanced cirrhosis related to an impairment in the renal capacity for eliminating solute-free water,causing a retention of water that is disproportionate to the retention of sodium,thus leading to a reduction in serum sodium concentration and *** main pathogenic factor responsible for hyponatraemia is a non-osmotic hypersecretion of arginine vasopressin(AVP)or antidiuretic hormone from the neurohypophysis,related to circulatory *** in cirrhosis is associated with increased morbidity and *** is also associated with increased morbidity and impaired short-term survival after *** current standard of care based on restricting fluids to 1-1.5 l/day is rarely *** approaches,such as albumin infusion and the use of vaptans—which act by specifically antagonizing the effects of AVP on the V2 receptors located in the kidney tubules—have been evaluated for their role in the management of *** short-term treatment with vaptans is associated with a marked increase in renal solute-free water excretion and improvement of hyponatraemia;however their use in patients with end-stage liver disease is limited by hepatotoxic effects of some of these *** administration of vaptans seems to be effective in maintaining the improvement of serum sodium concentration,but the available information is still limited.

关键词： hyponatraemia cirrhosis end-stage liver disease vaptans

Platelet rich plasma(PRP)induces autophagy in osteoblast precursor 3T3-l1

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BIOCEll 2018年第1期42卷 13-16页

作者： SERGIO andres CARMINATI MARÍA CAROlINA BARBOSA ClAUDIO MARCElO FADER Universidad Nacional de Cuyo Facultad de OdontologíaMendozaArgentina Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET).Instituto de Histología y Embriología(IHEM) Facultad de Ciencias MédicasUniversidad Nacional de CuyoMendozaArgentina

Autophagy is an essential cellular homeostatic mechanism by which intracellular components are delivered into the lysosomes for degradation and *** has been related with a diversity of pathological or physiological dentary processes such as bone remodeling,skeletal aging,osteoclastogenesis,osteoblastogenesis and different types of oral ***-rich plasma(PRP),isolated from autologous blood,is a plasma preparation containing a higher concentration of platelets which contains numerous different growth factors and cytokines that activate several cellular signaling *** purpose of this study is to investigate the effect of PRP on autophagy stimulation in both osteoblast precursor 3T3-l1 and non-related osteoblastic *** results showed that PRP can increase the number of autophagic structures in 3T3-l1 and Hela(cervical cancer cells)***,we have determined by Western blot a rise in the lipidated form of the autophagic protein lC3(***3-II)upon PRP *** together,our results suggest that PRP is able to induce a strongly autophagy response in osteoblast precursor and,to a lesser extent,in non-related osteoblastic cells,suggesting that PRP could be a potential therapeutic tool for some autophagy-related diseases associated with bone homeostasis.

关键词： Autophagy 3T3-l1 Platelet rich plasma Odontology