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Oxidative Degradation of Thermoplastic Starch Induced by Uv Radiation

Journal of Renewable Materials 2019年第4期7卷 383-391页

作者： Mayte M.Quispe olivia v.López Marcelo A.villar Planta Piloto de Ingeniería Química PLAPIQUI(UNS CONICET)Bahía Blanca(8000)Argentina Departamento de Ingeniería Química Universidad Nacional del Sur(UNS)Bahía Blanca(8000)Argentina

Among biopolymers,thermoplastic starch(TPS)is a good candidate to obtain biomaterials because of its natural origin,biodegradable character,and *** to ultraviolet(Uv)radiation causes significant degradation of starch-based materials,inducing photooxidative reactions which result in breaking of polymer chains,production of free radical,and reduction of molar *** changes produce a deterioration of TPS mechanical properties,leading to useless materials after an unpredictable *** this work,changes induced on TPS by Uv radiation,analyzing structural properties and mechanical behavior,are *** was obtained through thermo-mechanical processing of native corn starch in the presence of water(45%w/w)and glycerol(30%w/w)as *** were obtained by thermocompression and,before testing,specimens were conditioned to reduce material *** process was performed by exposing TPS to 264 h Uv radiation in a weathering test ***’s weight loss was determined *** changes were studied by Fourier Transform Infrared Spectroscopy(FTIR)and morphological modifications were analyzed by Scanning Electron Microscopy(SEM).Reduction of weight average molar mass was measured by Static Light Scattering(SLS).Changes in mechanical properties were studied from tensile *** 96 h exposure,TPS specimens presented a weight reduction of 4-6%,mainly attributed to plasticizers lost by *** observations showed that Uv radiation induced morphological changes on TPS,evidenced by an increment of specimens *** FTIR,it was detected the presence of an additional band located at 1726 cm-1 in samples submitted to Uv radiation,attributed to the formation of-C=O *** average molar mass of native starch was in the order of 107 g *** exposure to Uv radiation decreased significantly its molar mass,confirming molecular degradation of the *** TPS was exposed during 48 h,it

关键词： Thermoplastic starch Uv radiation structural properties mechanical behavior

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Standardized bioactive fraction of Phaleria macrocarpa(Proliverenol) prevents ethanol-induced hepatotoxicity via down-regulation of NF-kB-TNFα-caspase-8 pathway

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Asian Pacific Journal of Tropical Biomedicine 2016年第8期6卷 686-691页

作者： Guntur Berlian olivia Mayasari Tandrasasmita Raymond Rubianto Tjandrawinata Dexa Laboratories of Biomolecular Sciences PT Dexa Medica Industri Selatan V Block PP no.7 Kawasan Industri Jababeka Ⅱ

Objective: To verify that Proliverenol has a potential ability in protecting cells from ethanol-induced ***: Activity of Proliverenol against ethanol-induced apoptosis was evaluated at m RNA and protein levels in Hep G2 cell exposed to Proliverenol for 1 and 3 ***: Proliverenol conferred hepatoprotective activity through increasing cell survival up to 53%–69% via up-regulation of APEX1 DNA repair enzyme for 3.0–4.7 fold and down-regulating of nuclear factor-kB, tumor necrosis factora and caspase-8 expression,allowing them to prevent 4.5–6.9 fold of alanine aminotransferase(ALT) leakage in Hep G2 cells. Our finding revealed that Proliverenol repressed expression of ALT, which is significantly important as possible alternative mechanism for increased blood transaminase activities. In addition, the result also showed that caspase-8 pathway seemed to be involved in the molecular pathway rather than directly inducing mitochondrial ***: The data support our hypothesis that Proliverenol has a potential ability in protecting cells from ethanol-induced hepatotoxicity. We propose that Proliverenol provides hepatoprotective activity through up-regulating expression of APEX1 that repress DNA fragmentation, and down-regulating expression of nuclear factor-kB, tumor necrosis factora and caspase-8, which therefore repress ALT leakage and its expression.

关键词： Phaleria macrocarpa Hepatoprotector Liver injury Cirrhosis HepG2

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Trombinol,a bioactive fraction of Psidium guajava,stimulates thrombopoietin expression in HepG2 cells

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Asian Pacific Journal of Tropical Biomedicine 2017年第5期7卷 437-442页

作者： Guntur Berlian olivia Mayasari Tandrasasmita Raymond Rubianto Tjandrawinata Section of Molecular Pharmacology Dexa Laboratories of Biomolecular Sciences Dexa MedicaIndustri Selatan VBlock PP No.7Jababeka Industrial Estate IICikarangWest Java 17550Indonesia

Objective:To study the regulation of trombinol on thrombopoietin,an essential regulator of thrombocyte ***:Effect of trombinol on thrombopoietin regulation was evaluated at the m RNA and protein levels in human hepatoma Hep G2 *** m RNA expressions were revealed by PCR and real-time PCR,while the protein expressions were analyzed using western blotting and human ELISA *** differences between the test were determined by student's t-test with P vel of m RNA and protein secretion in Hep G2 cell *** with the concentration of15 mg/m L,positively induces 2.5-fold of thrombopoietin ***-regulation of GABP,a transcription factor of thrombopoietin,is suggested to be involved in cellular regulatory mechanisms of ***,our result shows convincing evidence that trombinol affects the thrombopoietin productions in *** molecular explanation of thrombopoietin's stimulating function is in line with the traditional use of Psidium guajava for treatment of diseases involving ***:Thrombopoietin stimulating function of trombinol could be potentially considered as one of alternative treatment for thrombocytopenia-related cases,including post chemotherapy shock,dengue fever and liver failure.

关键词： Trombinol Thrombopoietin Thrombocyte Anti-thrombocytopenia Thrombopoietin stimulating agent

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First experience in laparoscopic surgery in low and middle income countries: A systematic review

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 546-553页

作者： Rebekka Troller Jasmine Bawa olivia Baker James Ashcroft Department of Surgery Medway Maritime HospitalGillingham ME75NYKentUnited Kingdom Department of Surgery University Hospital CambridgeCambridge CB20QQUnited Kingdom

BACKGROUND Laparoscopic surgery has reduced morbidity and mortality rates,shorter post-operative recovery periods and lower complication rates than open *** is routine practice in high-income countries and is becoming increasingly common in countries with limited ***,introducing laparoscopic surgery in low-and-middle-income countries(LMIC)can be expensive and requires resour-ces,equipment,and *** To report the challenges and benefits of introducing laparoscopic surgery in LMIC as well as to identify solutions to these challenges for countries with limited finances and *** MEDLINE,EMBASE and Cochrane databases were searched for studies reporting first experience in laparoscopic surgery in *** studies were published between 1996 and 2022 with full text available in *** criteria were studies considering only open surgery,ear,nose,and throat,endoscopy,arthro-scopy,hysteroscopy,cystoscopy,transplant,or bariatric *** Ten studies out of 3409 screened papers,from eight LMIC were eligible for inclusion in the final analysis,totaling 2497 *** reported challenges were related to costs of equipment and training programmes,equipment pro-blems such as faulty equipment,and access to surgical ***-related challenges were reliance on foreign trainers and lack of locally trained surgeons and theatre *** benefits of introducing laparoscopic surgery were economic and clinical,including a reduction in hospital stay,complications,and morbidi-ty/*** introduction of laparoscopic surgery also provided training opportunities for junior *** Despite financial and technical challenges,many studies emphasise the overall benefit of introducing laparoscopic surgery in LMICs such as reduced hospital stay and the related lower cost for *** many of the clinical centres in LMICs have proposed practical solutions to the challenges reported,more support is critical

关键词： Laparoscopic surgery Low and middle income country First experience Training in laparoscopic surgery

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Bacterial and archaeal communities in saline soils from a Los Negritos geothermal area in Mexico

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Pedosphere 2023年第2期33卷 312-320页

作者： Joseph GUEvARA-LUNA Mario HERNÁNDEZ-GUZMÁN Nina MONTOYA-CIRIACO Luc DENDOOvEN Marina olivia FRANCO-HERNÁNDEZ Paulina ESTRADA-DE LOS SANTOS María Soledad vÁSQUEZ-MURRIETA Escuela Nacional de Ciencias Biológicas Instituto Politécnico NacionalCiudad de México 11340(Mexico) Laboratory of Soil Ecology CinvestavMexico City 07360(Mexico) Centro Tlaxcala de Biología de la Conducta Universidad Autónoma de Tlaxcala.Carretera Federal Tlaxcala-Puebla km.1.5Tlaxcala 90070(Mexico) Unidad Profesional Interdisciplinaria de Biotecnología Instituto Politécnico NacionalCiudad de México 07340(Mexico)

In recent years,there has been a growing need to understand how salinity affects microbial communities in agricultural *** and bacterial community diversities and structures were investigated by high-throughput sequencing analysis of their 16S rRNA in two arable soils with low electrical conductivity(EC)(2.3 and 2.6 dS m^(-1))and a saline soil(EC=17.6 dS m^(-1)).The dominant bacterial phyla in the soils were Proteobacteria(relative abundance(RA)=46.2%),followed by Acidobacteria(RA=13.1%)and Actinobacteria(RA=10.0%),whereas Serratia(RA=6.0%)and Bacillus(RA=4.0%)were the dominant bacterial *** Nitrososphaera(53.5%)was the dominant archaeal phylotype in the arable soils,whereas Nitrosopumilus(RA=0.4%)dominated in the saline *** archaeal and bacterial community structures were different between the soils and significantly correlated with soil sand,arsenic,barium,and antimony contents,but not with soil salinity.

关键词： agricultural soil compositional approach microbial community mud volcano soil salinity soluble anion

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Parametrically constrained geometry relaxations for high-throughput materials science

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npj Computational Materials 2019年第1期5卷 63-72页

作者： Maja-olivia Lenz Thomas A.R.Purcell David Hicks Stefano Curtarolo Matthias Scheffler Christian Carbogno Fritz-Haber-Institut der Max-Planck-Gesellschaft Faradayweg 4–6D-14195 BerlinGermany Department of Mechanical Engineering and Materials Science Duke UniversityDurhamNC 27708USA

Reducing parameter spaces via exploiting symmetries has greatly accelerated and increased the quality of electronic-structure ***,many of the traditional methods fail when the global crystal symmetry is broken,even when the distortion is only a slight perturbation(e.g.,Jahn-Teller like distortions).Here we introduce a flexible and generalizable parametric relaxation scheme and implement it in the all-electron code *** approach utilizes parametric constraints to maintain symmetry at any *** demonstrating the method’s ability to relax metastable structures,we highlight its adaptability and performance over a test set of 359 materials,across 13 lattice *** we show how these constraints can reduce the number of steps needed to relax local lattice distortions by an order of *** flexibility of these constraints enables a significant acceleration of high-throughput searches for novel materials for numerous applications.

关键词： relaxation constraints distortion

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Biocomposites Based on Thermoplastic Starch and Granite Sand Quarry Waste

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Journal of Renewable Materials 2019年第4期7卷 393-402页

作者： María G.Passaretti Mario D.Ninago Cecilia I.Paulo Horacio A.Petit Edgardo F.Irassarc Daniel A.vega Marcelo A.villar olivia v.López Planta Piloto de Ingeniería Química PLAPIQUI(UNS-CONICET)Camino"La Carrindanga"Km 7Bahía Blanca8000Buenos AiresArgentina Departamento de Ingeniería Química Universidad Nacional del Sur(UNS)Bahía Blanca8000Buenos AiresArgentina Facultad de Ciencias Aplicadas a la Industria(FCAI) Universidad Nacional de Cuyo(UNCuyo)Bernardo de Irigoyen 375San Rafael5600MendozaArgentina Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Godoy Cruz 2290Ciudad Autónoma de Buenos AiresC1425FQBBuenos AiresArgentina Facultad de Ingeniería Universidad Nacional del Centro de la Provincia de Buenos Aires(UNCPBA).Centro de Investigaciones en Física e IngenieríaCIFICEN(UNCPBA-CICPBA-CONICET)7400OlavarríaArgentina Instituto de Física del Sur IFISUR(UNS-CONICET)Bahía Blanca8000Argentina

Granite stone is a by-product of the rock crushing *** industrial waste in powder form that causes health problems and environmental *** particles fraction can be used as a partial replacement of sand in concrete *** this work,an alternative exploitation of this waste fraction is *** sand(GS)with particles mean size of ~1μm was employed as thermoplastic starch(TPS)filler at different *** were obtained by melt-mixing and thermo-compression,achieving translucent and easy to handle films.A good GS dispersion within the matrix was evidenced by *** presence induced a shift of starch’s melting point to higher values and a better thermal *** Uv absorption capacity was increased ~90% by GS *** increment in TPS Young’s modulus and maximum tensile stress of 5 and 3 times,respectively was observed by adding 5%w/w GS.

关键词： Thermoplastic starch granite sand melt processing final properties

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Gastroparesis:New insights into an old disease

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World Journal of Gastroenterology 2020年第19期26卷 2333-2348页

作者： Paolo Usai-Satta Massimo Bellini olivia Morelli Francesca Geri Mariantonia Lai Gabrio Bassotti Department of Internal Medicine Division of GastroenterologyBrotzu HospitalCagliari 09124Italy Gastrointestinal Unit Department of Translational Research and New Technologies in Medicine and SurgeryUniversity of PisaPisa 56122Italy Gastroenterology and Hepatology Section Department of MedicineUniversity of Perugia Medical SchoolPerugia 06123Italy Gastroenterology Unit University of CagliariMonserrato 09042Italy

Gastroparesis(Gp)is a chronic disease characterized by a delayed gastric emptying in the absence of mechanical *** this condition has been reported in the literature since the mid-1900s,only recently has there been renewed clinical and scientific interest in this disease,which has a potentially great impact on the quality of *** aim of this review is to explore the pathophysiological,diagnostic and therapeutical aspects of Gp according to the most recent evidence.A comprehensive online search for Gp was carried out using MEDLINE and *** is the result of neuromuscular abnormalities of the gastric motor *** is evidence that patients with idiopathic and diabetic Gp may display a reduction in nitrergic inhibitory neurons and in interstitial cells of Cajal and/or *** regards diagnostic approach,99-Technetium scintigraphy is currently considered to be the gold standard for *** limits are a lack of standardization and a mild risk of radiation *** C13 breath testing is a valid and safe alternative method.13C acid octanoic and the 13C Spirulina platensis recently approved by the Food and Drug Administration are the most commonly used diagnostic *** wireless motility capsule is a promising technique,but its use is limited by costs and scarce availability in many ***,therapeutic strategies are related to the clinical severity of *** mild and moderate Gp,dietary modification and prokinetic agents are generally *** is the only drug approved by the Food and Drug Administration for ***,other older and new prokinetics and antiemetics can be *** a second-line therapy,tricyclic antidepressants and cannabinoids have been *** severe cases the normal nutritional approach can be compromised and artificial nutrition may be *** drug-unresponsive Gp patients some alternative strategies(endoscopic,electric stimulation or surgery)are available.

关键词： Gastroparesis Delayed gastric emptying Gastric Scintigraphy 13C breath testing Wireless motility capsule Prokinetics Antiemetic drugs Gastric-per-oral endoscopic myotomy Gastric electrical stimulation

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Controlling self-assembling and tumor cell-targeting of protein-only nanoparticles through modular protein engineering

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Science China Materials 2020年第1期63卷 147-156页

作者： Eric volta-Duran olivia Cano-Garrido Naroa Serna Hector Lopez-Laguna Laura Sanchez-Garcia Mireia Pesarrodona Alejandro Sanchez-Chardi Ramon Mangues Antonio villaverde Esther vazquez Ugutz Unzueta Institut de Biotecnologia i de Biomedicina Universitat Autònoma de BarcelonaBellaterra08193 BarcelonaSpain Departament de Genetica i de Microbiologia Universitat Autònoma de BarcelonaBellaterra08193 BarcelonaSpain CIBER de Bioingeniería Biomateriales y Nanomedicina(CIBER-BBN)C/Monforte de Lemos 3-528029 MadridSpain Nanoligent SL Edifici EUREKAUniversitat Autonoma de BarcelonaBellaterra08193 BarcelonaSpain Institut dInvestigacions Biomèdiques Sant Pau and Josep Carreras Research Institute Hospital de la Santa Creu i Sant Pau08041 BarcelonaSpain Departament de Biologia Evolutiva Ecologia i Ciencies AmbientalsFacultat de BiologiaUniversitat de BarcelonaAv.Diagonal 64308028 BarcelonaSpain Institute for Research in Biomedicine(IRB Barcelona) The Barcelona Institute of Science and Technology08028 BarcelonaSpain

Modular protein engineering is suited to recruit complex and multiple functionalities in single-chain polypeptides. Although still unexplored in a systematic way, it is anticipated that the positioning of functional domains would impact and refine these activities, including the ability to organize as supramolecular entities and to generate multifunctional protein materials. To explore this concept, we have repositioned functional segments in the modular protein T22-GFP-H6 and characterized the resulting alternative fusions. In T22-GFP-H6, the combination of T22 and H6 promotes selfassembling as regular nanoparticles and selective binding and internalization of this material in CXCR4-overexpressing tumor cells, making them appealing as vehicles for selective drug delivery. The results show that the pleiotropic activities are dramatically affected in module-swapped constructs, proving the need of a carboxy terminal positioning of H6 for protein self-assembling, and the accommodation of T22 at the amino terminus as a requisite for CXCR4^+ cell binding and internalization. Furthermore, the failure of self-assembling as regular oligomers reduces cellular penetrability of the fusions while keeping the specificity of the T22-CXCR4 *** these data instruct how multifunctional nanoscale protein carriers can be designed for smart, protein-driven drug delivery, not only for the treatment of CXCR4^+ human neoplasias, but also for the development of anti-HIv drugs and other pathologies in which CXCR4 is a relevant homing marker.

关键词： nanoparticles protein materials recombinant proteins drug delivery self-assembling cancer cell targeting

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Eccentric exercise-induced muscle weakness abolishes sex differences in fatigability during sustained submaximal isometric contractions

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Journal of Sport and Health Science 2023年第4期12卷 523-533页

作者： Hanna L.Jodoin Avery Hinks olivia P.Roussel vincenzo S.Contento Brian H.Dalton Geoffrey A.Power Department of Human Health and Nutritional Sciences College of Biological SciencesUniversity of GuelphGuelphON N1G 2W1Canada School of Health and Exercise Science University of British ColumbiaKelownaBC V1V 1V7Canada

Background:Females are typically less fatigable than males during sustained isometric contractions at lower isometric contraction *** sex difference in fatigability becomes more variable during higher intensity isometric and dynamic *** less fatiguing than isometric or concentric contractions,eccentric contractions induce greater and longer lasting impairments in force ***,it is not clear how muscle weakness influences fatigability in males and females during sustained isometric ***:We investigated the effects of eccentric exercise-induced muscle weakness on time to task failure(TTF)during a sustained submaximal isometric contraction in young(18-30 years)healthy males(n=9)and females(n=10).Participants performed a sustained isometric contraction of the dorsiflexors at 35°plantar flexion by matching a 30%maximal voluntary contraction(MvC)torque target until task failure(i.e.,falling below 5%of their target torque for>2 s).The same sustained isometric contraction was repeated 30 min after 150 maximal eccentric *** and antagonist activation were assessed using surface electromyography over the tibialis anterior and soleus muscles,***:Males were~41%stronger than *** eccentric exercise both males and females experienced an~20%decline in maximal voliuntary contraction *** was-34%longer in females than males prior to eccentic exercise-induced muscle ***,following eccentric exercise-induced muscle weakness,this sex-related difference was abolished,with both groups having an"45%shorter ***,there was~100%greater antagonist activation in the female group during the sustained isometric contraction following exercise-induced weakness as compared to the ***:This increase in antagonist activation disadvantaged females by decreasing their TTF,resulting in a blunting of their typical fatigability advantage over males.

关键词： Fatigue Isometric Sex Time to task failure Weakness

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