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Bioactive peptides: A review

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Food quality and Safety 2017年第1期1卷 29-46页

作者： Adrián Sánchez Alfredo Vázquez laboratorio de Investigación en Inmunoquímica Dr.Márquez 162CuauhtémocDoctores06720CDMX departamento de química orgánica Facultad de QuímicaUniversidad Nacional Autónoma de MéxicoMéxico

Bioactive peptides(BP)are organic substances formed by amino acids joined by covalent bonds known as amide or peptide *** some BP exist free in its natural source,the vast majority of known BP are encrypted in the structure of the parent proteins and are released mainly by enzymatic *** BP have been prepared by chemical *** play a significant role in human health by affecting the digestive,endocrine,cardiovascular,immune,and nervous *** are considered the new generation of biologically active regulators;they can prevent oxidation and microbial degradation in foods and also improve the treatment of various diseases and disorders,thus increasing the quality of *** growing interest in BP has incentivized the scientific community and the food industry to exploring the development of new food additives and functional products based on these *** present review highlights the recent findings on the identification,bioassays,and use of BP,as well as their potential use as food additives and in the development of functional products.

关键词： peptides bioactivity marine origin nutraceutical hydrolysis fermentation

Bioerosion on Late Pleistocene Marine Mollusks:A Paleoclimatological and Paleoecological Comparison of MIS 7 and MIS 5e with Modern Beaches(Río Negro,Argentina)

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1181-1198页

作者： Melisa P.CHARO Gisela D.CHARÓ Guillermo ACEÑOLAZA Jose L.CAVALLOTTO Instituto Superior de Correlación Geológica(INSUGEO/CONICET-UNT)Miguel Lillo 205 4000 TucumánArgentina laboratorio de Fluidodinámica Departamento de Ingeniería MecánicaFacultad de IngenieríaUniversidad de Buenos AiresPaseo Colón 850C1063ACVCiudad Autónoma de Buenos AiresArgentina Servicio de Hidrografía Naval Av.Montes de Oca 2124C1270ABW Buenos AiresArgentina

The Late Pleistocene littoral ridges of southern South America,especially those of the north of Argentinean Patagonia,contain remains of mollusk shells with bioerosion *** sites from marine isotope stages(2 from MIS 7,4 from MIS 5 e)and five sites from modern beaches from northern Río Negro Province,with 40 taxa(17 bivalves and 23 gastropods)were analyzed,in the area between west of Baliza San Matías and Las Grutas(41°S).Three ichnogenera were identified in deposits of MIS 7:Entobia,Gastrochaenolites(Domichnia)and Oichnus(Praedichnia)with one ichnospecies(***).Six ichnogenera were identified in deposits of MIS 5 e:Entobia,Meandropolydora,Pinaceocladichnus,Iramena,Caulostrepsis and Oichnus with one ichnospecies(***).Seven ichnogenera were identified from modern beaches:Entobia,Meandropolydora,Iramena,Caulostrepsis,Pinaceocladichnus,Gastrochaenolites(Domichnia)and Oichnus(Praedicnia),with two ichnospecies(*** and ***).On this basis,it is inferred that Pleistocene benthic communities were constituted from cheilostome bryzoans and polychaete annelids,together with drilling bivalves,predatory gastropods and overall warm-water species of *** these,Chama iudicai was found on Plicatula gibbosa from MIS 7 and MIS 5 *** record of warm temperature species suggests a higher sea surface temperature(SST)than the present one and/or the influence of the warm southward Brazilian Current affecting the waters of Golfo San Matí*** the modern beaches surveyed,there is an increase in polychaete annelids,cheilostome bryzoans,temperate-cold species and drilling bivalves,as well as sandy substrate species,which together with an increase of Gastrochaenolites and Caulostrepsis,suggest a colder climate due to the greater influence of the Malvinas Current during the Holocene.

关键词： invertebrate paleontology ichnology Bivalvia Gastropoda Polyplacophora bioerosion paleoclimatology paleoecology quaternary/Holocene Argentina

Influence of dissolved organic matter character on mercury incorporation by planktonic organisms: An experimental study using oligotrophic water from Patagonian lakes

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Journal of Environmental Sciences 2013年第10期25卷 1980-1991页

作者： María C.Diéguez Claudia P.queimalios Sergio Ribeiro Guevara Mark Marvin-DiPasquale Carolina Soto Crdenas María A.Arribre laboratorio de Fotobiología INIBIOMA CONICET-UNComahue laboratorio de Fotobiolog INIBIOMA CONICET-UNComahue laboratorio de Anlisis por Activación Neutrónica Centro Atómico Bariloche CNEA United States Geological Survey laboratorio de Anlisis por Activacio Neutrónica Centro Atómico Bariloche CNEA

Ligands present in dissolved organic matter （DOM） form complexes with inorganic divalent mercury （Hg^2＋） affecting its bioavailability in pelagic food webs. This investigation addresses the influence of a natural gradient of DOM present in Patagonian lakes on the bioaccumulation of Hg^2＋（the prevailing mercury species in the water column of these lakes） by the algae Cryptomonas erosa and the zooplankters Brachionus calyciflorus and Boeckella antiqua. Hg^2＋ accumulation was studied through laboratory experiments using natural water of four oligotrophic Patagonian lakes amended with^197Hg^2＋. The bioavailability of Hg^2＋ was affected by the concentration and character of DOM. The entrance of Hg^2＋ into pelagic food webs occurs mostly through passive and active accumulation. The incorporation of Hg^2＋ by Cryptomonas, up to 27% of the Hg^2＋ amended, was found to be rapid and dominated by passive adsorption, and was greatest when low molecular weight compounds with protein-like or small phenolic signatures prevailed in the DOM. Conversely, high molecular weight compounds with a humic or fulvic signature kept Hg^2＋ in the dissolved phase, resulting in the lowest Hg^2＋ accumulation in this algae. In Brachionus and Boeckella the direct incorporation of Hg from the aqueous phase was up to 3% of the Hg^2＋ amended. The dietary incorporation of Hg^2＋ by Boeckella exceeded the direct absorption of this metal in natural water, and was remarkably similar to the Hg^2＋ adsorbed in their prey. Overall, DOM concentration and character affected the adsorption of Hg^2＋ by algae through competitive binding, while the incorporation of Hg^2＋ into the zooplankton was dominated by trophic or dietary transfer.

关键词： mercury dissolved organic matter plankton mercury incorporation Patagonian lakes Argentina

Experimental study on lightweight expanded clay at particle level:Breakage of isolated grains

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第7期15卷 1846-1858页

作者： Elías Roces-Alonso Jose Estaire Miriam Martín-Ruiz Jesús González-Galindo ETS de Ingenieros de Caminos Universidad Politécnica de MadridSpain laboratorio de Geotecnia CEDEXMadridSpain

In this study,more than 1500 particles of lightweight expanded clay aggregate(LECA)are individually loaded up to breakage,following different patterns of contact(from 2 to 7)using a purpose-built ***,a statistical model for predicting the number of fragments into which a grain breaks as a function of the number of contacts and their diameter is *** number of fragments is found to follow a statistical binomial-type distribution function that depends on the number of *** addition,a model based on Bayesian networks,capable of assessing the number of fragments and their size(measured as normalized weight)as a function of the number of contacts,is *** proposed method is applicable when performing discrete element method(deM)simulations on granular media in which grain breakage plays a relevant role.

关键词： Lightweight expanded clay aggregate(LECA) Grain fragmentation Grain breakage Biaxial grain load

An internal control applied to RT-PCR detection of HCV and HIV-1 in human pooled plasma and plasma-derived medicinal products

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BIOCELL 2015年第2期39卷 15-23页

作者： Gonzalo RODRÍGUEZ-LOMBARDI Luciana REYNA María Susana VITALI Susana GENTI-RAIMONDI laboratorio de Hemoderivados Universidad Nacional de Córdoba Centro de Investigaciones en Bioquímica Clínica e Inmunología Departamento de Bioquímica ClínicaFacultad de Ciencias QuímicasUniversidad Nacional de Córdoba-Consejo Nacional de Investigaciones Científicas y TécnicasX5000HUA CórdobaArgentina

A competitive internal control(IC)adapted to RT-PCR in-house assay was developed for HCV RNA detection in human pooled ***,it was applied in a multiplex RT-PCR for the HIV-1 and HCV RNA screening in human pooled plasma and plasma-derived products.A 258-bp PCR product from the 5´non-coding region of HCV genome was obtained.A competitive IC template was constructed by inserting a 52-bp double strand sequence into the NheI site of the 258-bp *** sequence was cloned and the obtained plasmid was used to generate a synthetic *** IC/RNA was incorporated in in-house HCV and/or HIV PCR technique to monitor the efficiency of extraction,reverse transcription,and PCR amplification *** was also used to detect all major genotypes of HCV and HIV-1 strains with similar *** detection limit of the assay for HCV and HIV-1 was 52.7 IU/mL and 164.2 IU/mL,*** techniques have been evaluated in international programs of external quality assurance with highly satisfactory *** IC is an essential reagent in PCR techniques to detect and identify HCV and HIV-1 in pooled plasma samples involved in the manufacture of plasma-derived products as well as in the field of clinical microbiology with limited resources.

关键词： HCV HIV internal control RT-PCR

Artificial Triterpenoid Fatty Acid Ester Isolated From the Leaves of Phytolacca icosandra L

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Natural Products and Bioprospecting 2020年第4期10卷 221-225页

作者： Elier Galarraga Andersson Mavares Neudo Urdaneta Rafael ERodríguez-Lugo Juan Manuel Amaro-Luis departamento de química.Edificio de química Y Procesos Universidad Simón Bolívar(USB)Apartado 89000.Caracas-1080AVenezuelaUSA laboratorio de química Bioinorgánica Centro de QuímicaInstituto Venezolano de Investigaciones Científicas(IVIC)VenezuelaCaracas 1020-AUSA laboratorio de Productos Naturales Departamento de Química.Facultad de CienciasUniversidad de Los Andes(ULA)MéridaVenezuela-5101USA

The methanol extract form the leaves of Phytolacca icosandra L.,afforded the unprecedented artificial triterpenoid fatty acid ester 1 derived from the new natural triterpenoid phytolaccagenic acid 3-O-myristate(1a),along with the three known triterpenoids serjanic,acinosolic and phytolaccagenic acid(2-4).Their structures were stablished by HR-EI-MS,1D and 2D NMR *** possible mechanistic formation of 1 is proposed,and the in vitro toxicity of all compounds was assessed using the brine shrimp lethality assay(BSLA).

关键词： Phytolacca icosandra.triterpenoid fatty acid ester NMR artificial products BSLA

The short form of the SUR1 and its functional implications in the damaged brain

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Neural Regeneration Research 2022年第3期17卷 488-496页

作者： Iván Alquisiras-Burgos Javier Franco-Pérez Moisés Rubio-Osornio Penélope Aguilera laboratorio de Patología Vascular Cerebral Instituto Nacional de Neurología y Neurocirugía“Manuel Velasco Suárez”CDMXMexico laboratorio de Formación Reticular Instituto Nacional de Neurología y Neurocirugía“Manuel Velasco Suárez”CDMXMexico laboratorio Experimental de Enfermedades Neurodegenerativas Instituto Nacional de Neurología y Neurocirugía“Manuel Velasco Suárez”CDMXMexico.

Sulfonylurea receptor(SUR) belongs to the adenosine 5′-triphosphate(ATP)-binding cassette(ABC) transporter family;however,SUR is associated with ion channels and acts as a regulatory subunit determining the opening or closing of the ***8 and Abcc9 genes code for the proteins SUR1 and SUR2,*** SUR1 transcript encodes a protein of 1582 amino acids with a mass around 140–177 k Da expressed in the pancreas,brain,heart,and other *** is well known that SUR1 assembles with Kir6.2 and TRPM4 to establish K_(ATP) channels and non-selective cation channels,***8 and 9 are alternatively spliced,and the resulting transcripts encode different isoforms of SUR1 and SUR2,which have been detected by different experimental ***,the use of binding assays to sulfonylureas and Western blotting has allowed the detection of shorter forms of SUR(-65 k Da).Identity of the SUR1 variants has not been clarified,and some authors have suggested that the shorter forms are ***,immunoprecipitation assays have shown that SUR2 short forms are part of a functional channel even coexisting with the typical forms of the receptor in the *** evidence confirms that the structure of the short forms of the SURs is fully functional and does not lose the ability to interact with the *** structural changes in short forms of SUR modify its affinity to ATP,regulation of its expression might represent an advantage in pathologies where ATP concentrations decrease and a therapeutic target to induce ***,the expression of SUR1 variants might be induced by conditions associated to the decrease of energetic substrates in the brain(*** stroke and epilepsy).In this review,we want to contribute to the knowledge of SUR1 complexity by analyzing evidence that shows the existence of short SUR1 variants and its possible implications in brain function.

关键词： brain edema epilepsy Parkinson's disease stroke sulfonylurea receptor 1 SUR1 traumatic brain injury TRPM4

Biorefinery of Rice Husk to Obtain Functionalized Bioactive Compounds

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Journal of Renewable Materials 2019年第4期7卷 313-324页

作者： M.Lopretti N.Lecot A.Rodriguez G.Lluberas F.Orozco L.Bolaños G.Montes de Oca H.Cerecetto J.Vega-Baudrit laboratorio de Técnicas Nucleares Aplicadas a Bioquímica y Biotecnología Centro de Investigaciones Nucleares-Facultad de CienciasMataojo 2055Montevideo CP 11400Uruguay Área de Radiofarmacia Centro de Investigaciones Nucleares-Facultad de CienciasMataojo 2055Montevideo CP 11400Uruguay química Bioanalítica Instituto Polo Tecnológico de Pando-Facultad de QuímicaUdelaRBy Pass de Pando y Ruta 8Pando-Canelones CP 91000Uruguay laboratorio de Nacional de Nanotecnología-CeNAT-CONARE Costa Rica 1174-1200San JoséCP 10109Costa Rica laboratorio de Polímeros POLIUNA-Escuela de Química Universidad NacionalHerediaSan JoséCP 86-3000Costa Rica

The biomass industrialization valorisation of grains and cereals is considered an opportunity for the countries where agro-industrial activity is one of its main economic activities,rendering new higher-value products with a concomitant solution to waste accumulation *** that end,in this work we describe and characterise bioactive compounds generation from rice husk by semisolid fermentation,obtained from 500 g of the material at room temperature and 60%humidity with mixed cultures of Phanerochaete chrysosporium and Gloeophyllum *** extract was evaluated in different situations:murine mammary tumour cells(4T1),normal cells(NIH 3T3)and in Lactobacillus acidophilus,and Trichoderma *** results exhibited that the extract inhibited 4T1 cells at concentrations higher than 20μg/mL,but did not inhibit normal cells,and displayed germicide activity after 3 days *** propose that these functionalized compounds have a potential application in industry/agriculture/medicine obtained from rice husk waste.

关键词： Biorefinery rice husk bioactive compounds valorisation of biomass veratryl alcohol

Electrochemical reduction of Cr(Ⅵ)in the presence of sodium alginate and its application in water purification

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Journal of Environmental Sciences 2021年第3期33卷 304-312页

作者： Bryan Butter Paola Santander Guadalupe del CPizarro Diego POyarzún Federico Tasca Julio Sánchez Facultad de química y Biología Universidad de Santiago de ChileUSACHCasilla 40Correo 33SantiagoChile departamento de química Universidad Tecnológica MetropolitanaJ.P.Alessandri 1242SantiagoChile laboratorio de Nanotecnología Recursos Naturales y Sistemas ComplejosFacultad de Ciencias NaturalesUniversidad de AtacamaCopayapu 485CopiapóChile

Chromium(Cr)is used in many manufacturing processes,and its release into natural waters is a major environmental problem *** concentrations of Cr(Ⅵ)are toxic to human health and living organisms due to the carcinogenic and mutagenic nature of this *** work examined the conversion of Cr(Ⅵ)to Cr(Ⅲ)via electrochemical reduction using gold electrode in an acidic sodium alginate(SA)solution and subsequent removal of the produced Cr(Ⅲ)-SA by the polymer-enhanced ultrafiltration(PEUF)technique.A solution of SA in nitric acid was used both as an electrolytic medium during the voltammetric measurements and bulk electrolysis and as an extracting agent during the PEUF *** electroanalysis of Cr(Ⅵ)was performed by linear sweep voltammetry in the presence of acidic SA solution to study its voltammetric behavior as a function of the Cr(Ⅵ)concentration,pH,presence of Cr(Ⅲ),SA concentration and scan *** addition,the quantitative reduction of Cr(Ⅵ)to Cr(Ⅲ)was studied through the bulk electrolysis *** results showed efficient reduction with well-defined peaks at approximately 0.3 V ***/AgCl,using a gold working *** the pH increased,the reduction signal strongly decreased until its *** optimum SA concentration was 10 mmol/L,and it was observed that the presence of Cr(Ⅲ)did not interfere in the Cr(Ⅵ)*** the quantitative reduction by bulk electrolysis in the presence of acidic SA solution,it was possible to reduce all Cr(Ⅵ)to Cr(Ⅲ)followed by its removal via PEUF.

关键词： Alginate solution Chromium Electroanalytical chemistry Ultrafiltration Water purification