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Chalcone analogue as potent anti-malarial compounds against plasmodium falciparum:Synthesis,biological evaluation,and docking simulation study

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Asian pacific Journal of Tropical Biomedicine 2017年第8期7卷 675-679页

作者： Jufrizal Syahri Emmy Yuanita Beta Achromi Nurohmah ria Armunanto Bambang purwono Department of Chemistry Universitas Muhammadiyah Riau Department of Chemistry Universitas Gadjah Mada Department of Chemistry Universitas Mataram

To investigate in vitro antimalarial activity of chalcone derivative compounds against plasmodium falciparum 3D7 (pf3D7) strain and in silico antimalarial *** of the chalcone derivatives was conducted via Claisen-Schmidt method using NaOH 60% base as catalyst. An in vitro antimalarial activity assay was carried out according to the Rieckmann method against the chloroquine-sensitive pf3D7 strain. Molecular docking studies of the prepared compounds were performed using Discovery Studio 3.1 (Accelrys, Inc., San Diego, USA) software to dihydrofolate reductases-thymidylate synthase (pfDHFR-TS) protein with protein Data Bank ID of *** (sensitive-protein) and ID: *** (resistance-protein).ResultsThis work has successfully synthesized seven chalcone derivatives with a great antimalarial activity. It has been revealed that allyloxy, hydroxy and alkoxy functional groups could increase the antimalarial activity of the chalcone derivatives. The best antimalarial activity of the prepared compounds was possessed by 3b with an IC50 value of 0.59 μM and categorized as an excellent antiplasmodial. Molecular docking studies of 3b showed binding interaction with the amino acid residues such as Ala16, Ile164, phe58, Tyr170 of the *** protein and also Ala16, phe58, Ile112, Met55 of the *** *** in vitro antimalarial assay of the prepared chalcone derivative (3a-g) showed an excellent and good antiplasmodial activity against the chloroquine-sensitive pf3D7 strain. In silico antimalarial studies revealed that 3a-g made binding interaction with both sensitive-protein (***) and resistance-protein (***), which means that they were both active against chloroquine-sensitive and resistant plasmodium strain.

关键词： Antimalarial Chalcone Docking plasmodium falciparum 3D7

Characterization of the High-Strength Mg–3Nd–0.5Zn Alloy prepared by Thermomechanical processing

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Acta Metallurgica Sinica(English Letters) 2019年第3期32卷 321-331页

作者： Ji■í Kub■sek Drahomír Dvorsk■ Jozef Vesel■ peter Min■rik M■ria Zemkov■ Dalibor Vojtěch Department of Metals and Corrosion Engineering Faculty of Chemical Technology University of Chemistry and Technology Prague Department of physics of materials Charles University

magnesium alloys based on Nd and Zn are promising materials for both aviation industry and medical *** mechanical properties of these materials can be achieved by thermomechanical processing such as extrusion or rolling and by aging treatment, which can significantly strengthen the alloy. The question remains especially about the connection of texture strength created in the alloys based on the specific conditions of preparation. This work focuses on the Mg–3 Nd–0.5 Zn magnesium alloy prepared by hot extrusion of the as-cast state at two different temperatures combined with heat pre-treatment. Extrusion ratio of 16 and rate of 0.2 mm/s at 350 and 400 °C were selected for material preparation. The structures of prepared materials were studied by scanning electron microscopy and transmission electron microscopy. The effect of microstructure on mechanical properties was evaluated. Obtained results revealed the strong effect of thermal pre-treatment on final microstructure and mechanical properties of extruded materials. The Hall–petch relation between grain size and tensile yield strength has been suggested in this paper based on the literature review and presented data. The observed behavior strongly supports the fact that the Hall–petch of extruded Mg–3Nd–0.5 Zn alloys with different texture intensities cannot be clearly estimated and predicted. In addition, Hall–petch relations presented in literature can be sufficiently obtained only for fraction of the Mg–3Nd–0.5 Zn alloys.

关键词： Mg–Nd–Zn alloys Extrusion Thermal treatment Microstructure Mechanical properties

New serological markers in pediatric patients with inflammatory bowel disease

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World Journal of Gastroenterology 2014年第17期20卷 4873-4882页

作者： Márta Kovács Katalin Eszter Müller Mária papp péter László Lakatos Mihály Cs?ndes Gábor Veres Department of pediatrics Petz Aladár County and Teaching Hospital9023 Gy?rHungary 1~(st) Department of pediatrics Semmelweis University1083 BudapestHungary 2~(nd) Department of Medicine University of Debrecen4032 DebrecenHungary 1~(st) Department of Medicine Semmelweis University1083 BudapestHungary Department of Gastroenterology Petz Aladár County and Teaching Hospital9023 Gy?rHungary

The spectrum of serological markers associated with inflammatory bowel disease (IBD) is rapidly growing. Due to frequently delayed or missed diagnoses, the application of non-invasive diagnostic tests for IBD, as well as differentiation between ulcerative colitis (UC) and Crohn’s disease (CD), would be useful in the pediatric population. In addition, the combination of pancreatic autoantibodies and antibodies against Saccharomyces cerevisiae antibodies/perinuclear cytoplasmic antibody (pANCA) improved the sensitivity of serological markers in pediatric patients with CD and UC. Some studies suggested that age-associated differences in the patterns of antibodies may be present, particularly in the youngest children. In CD, most patients develop stricturing or perforating complications, and a significant number of patients undergo surgery during the disease course. Based on recent knowledge, serum antibodies are qualitatively and quantitatively associated with complicated CD behavior and CD-related surgery. pediatric UC is characterized by extensive colitis and a high rate of colectomy. In patients with UC, high levels of anti-CBir1 and pANCA are associated with the development of pouchitis after ileal pouch-anal anastomosis. Thus, serologic markers for IBD can be applied to stratify IBD patients into more homogeneous subgroups with respect to disease progression. In conclusion, identification of patients at an increased risk of rapid disease progression is of great interest, as the application of early and more aggressive pharmaceutical intervention could have the potential to alter the natural history of IBD, and reduce complications and hospitalizations.

关键词： Inflammatory bowel disease, Crohn’ s disease, Ulcerative colitis, pediatric, Serologic markers, Antimicrobial antibodies, Anti-glycan antibodies, pancreatic antibodies, Inflammatory bowel disease

Identify multiple myeloma stem cells: Utopia?

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World Journal of Stem Cells 2015年第1期7卷 84-95页

作者： Ilaria Saltarella Aurelia Lamanuzzi Antonia Reale Angelo Vacca Roberto ria Department of Biomedical Sciences and Human Oncology Section of Internal Medicine "G. Baccelli" University of Bari "Aldo Moro" Medical School Policlinico I-70124 Bari Italy

Multiple myeloma(MM) is a hematologic malignancy of monoclonal plasma cells which remains incurable despite recent advances in therapies. The presence of cancer stem cells(CSCs) has been demonstrated in many solid and hematologic tumors, so the idea of CSCs has been proposed for MM, even if MM CSCs have not been define yet. The existence of myeloma CSCs with clonotypic B and clonotypic non B cells was postulated by many groups. This review aims to focus on these distinct clonotypic subpopulations and on their ability to develop and sustain MM. The bone marrow microenvironment provides to MM CSCs self-renewal, survival and drug resistance thanks to the presence of normal and cancer stem cell niches. The niches and CSCs interact each other through adhesion molecules and the interplay between ligands and receptors activate stemness signaling(Hedgehog, Wnt and Notch pathways). MM CSCs are also supposed to be responsible for drug resistance that happens in three steps from the initial cancer cell homing microenvironment-mediated to development of microenvironment-independent drug resistance. In this review, we will underline all these aspects of MM CSCs.

关键词： Bone marrow microenvironment Cancerstem cells Multiple myeloma Stem cells niche Stemness

Subcellular distribution of nitric oxide synthase isoforms in the rat duodenum

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World Journal of Gastroenterology 2011年第8期17卷 1026-1029页

作者： petra Talapka Nikolett Bódi Izabella Battonyai éva Fekete Mária Bagyánszki Department of physiology Anatomy and Neuroscience University of Szeged

AIM:To study the cell-type specific subcellular distribution of the three isoforms of nitric oxide synthase(NOS) in the rat ***:postembedding immunoelectronmicroscopy was performed,in which primary antibodies for neuronal NOS(nNOS),endothelial NOS(eNOS),and inducible NOS(iNOS),were visualized with protein A-gold-conjugated secondary *** ultrathin sections were examined and photographed with a philips CM10 electron microscope equipped with a MEGAVIEW II *** specificity of the immunoreaction in all cases was assessed by omitting the primary antibodies in the labeling protocol and incubating the sections only in the protein A-gold conjugated secondary ***:postembedding immunoelectronmicroscopy revealed the presence of nNOS,eNOS,and iNOS immunoreactivity in the myenteric neurons,the enteric smooth muscle cells,and the endothelium of capillariesrunning in the vicinity of the myenteric plexus of the rat *** cell type-specific distributions of the immunogold particles labeling the three different NOS isozymes were *** the control experiments,in which the primary antiserum was omitted,virtually no postembedding gold particles were ***:This postembedding immunoelectronmicroscopic study provided the first evidence of celltype-specific differences in the subcellular distributions of NOS isoforms.

关键词： postembedding immunoelectronmicroscopy Subcellular distribution Neuronal nitric oxide synthase Endothelial nitric oxide synthase Inducible nitric oxide synthase

The bone marrow niche landscape:a journey through aging,extrinsic and intrinsic stressors in the haemopoietic milieu

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Journal of Cancer Metastasis and Treatment 2022年第1期8卷 526-537页

作者： Antonio Giovanni Solimando Assunta Melaccio Angelo Vacca Roberto ria Department of Biomedical Sciences and Human Oncology Section of Internal Medicine and Clinical OncologyUniversity of Bari Medical SchoolBari 70124 Italy

Inflammation and its effects in the bone marrow microenvironment represent a paradigmatic condition in which the hematopoietic niche and the immune systems,thought to properly sustain blood cell production and distinguish between friend and foe,can actively sustain a corrupted neighborhood within a chronic aberrant inflamed *** bone marrow niche hijacks the physiologic *** interactions between the hematopoietic stem cells and the niche in the bone marrow are critical determinants of *** examined several approaches to confront the available evidence;three key points emerged,pointing to the chronic inflammation process,especially the chronic infection and systemic inflammatory states,as leading causes of hematopoietic stem cell *** hematopoiesis,defined as a relative expansion of individual clones,is caused by somatic alterations in essential hematopoietic genes,which increase stem cell ***,terminal differentiation plays a significant role in progenitor loss and inflammatory signaling,promoting clonal selection and clonal hematopoiesis *** myeloid malignancies as paradigmatic examples are discussed as a condition associated with inflammation,including the 5q-syndrome,philadelphia negative myeloproliferative neoplasms,and chronic myeloid *** with increased fitness and hematopoietic stem cell attrition,extrinsic stress,enhanced stressor-specific fitness,and intrinsic defect across the hematopoietic process represent the route for novel insights in defective *** discussion in this review also points out that the hematopoietic niches’inflammatory stimulation may affect differentiation patterns and the function of downstream cells.

关键词： Hematopoietic niche immune system inflammation tumor microenvironment

Evaluation of Terra/MODIS atmospheric profiles product(MOD07)over the Iberian peninsula:a comparison with radiosonde stations

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International Journal of Digital Earth 2015年第10期8卷 771-783页

作者： JoséA.Sobrino Juan C.Jiménez-Muñoz Cristian mattar Guillem Sòria Global Change Unit–Image processing Laboratory University of ValenciaValenciaSpain Laboratory for Analysis of the Biosphere Universidad de ChileSantiagoChile

Remote sensing techniques are a useful tool for continuous observation of the Earth at global ***,products derived from remote sensing data require a rigorous validation using in situ *** Resolution Imaging Spectroradiometer(MODIS)is not really a sounding instrument,but it does have 16 infrared bands(bands 20-36 covering the spectral range from 3μm to 14μm)that allow the retrieval of temperature and moisture profiles as well as total column integrated *** this paper we show the results obtained in the evaluation of MOD07 daytime and nighttime products over the Iberian peninsula during the decade from 2000 to 2010 using nine radiosonde *** MODIS limitations in comparison with other sounding instruments,the validation provided satisfactory results,with bias(MOD07 minus radiosonde)por,and bias around 1 K on average with standard deviations between 2 K and 3 K for air temperature at different pressure *** average,bias was positive and below 2 K with standard deviations around 5 K for the dew point temperature *** errors were found in this case for pressure levels higher than 50 hpa.

关键词： MODIS MOD07 atmospheric profiles water vapor air temperature dew point temperature

Single-atom heterogeneous catalysts based on distinct carbon nitride scaffolds

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National Science Review 2018年第5期5卷 642-652页

作者： Zupeng Chen Evgeniya Vorobyeva Sharon Mitchell Edvin Fako Nuúria López Sean M.Collins Rowan K.Leary paul A.Midgley RolAND Hauert Javier pérez-Ramírez Institute for Chemical and Bioengineering Department of Chemistry and Applied BiosciencesETHZurich Institute of Chemical Research of Catalonia (ICIQ) The Barcelona Institute of Science and Technology 3. Department of Materials Science and MetallurgyUniversity of Cambridge 4. EmpaSwiss Federal Laboratories for Materials Science and Technology

Carbon nitrides integrating macroheterocycles offer unique potential as hosts for stabilizing metal atoms due to their rich electronic structure. To date, only graphitic heptazine-based polymers have been ***, we demonstrate that palladium atoms can be effectively isolated on other carbon nitride scaffolds including linear melem oligomers and poly(triazine/heptazine imides). Increased metal uptake was linked to the larger cavity size and the presence of chloride ions in the polyimide structures. Changing the host structure leads to significant variation in the average oxidation state of the metal, which can be tuned by exchange of the ionic species as evidenced by X-ray photoelectron spectroscopy and supported by density functional theory. Evaluation in the semi-hydrogenation of 2-methyl-3-butyn-2-ol reveals an inverse correlation between the activity and the degree of oxidation of palladium, with oligomers exhibiting the highest activity. These findings provide new mechanistic insights into the influence of the carbon nitride structure on metal stabilization.

关键词： single-atom heterogeneous catalysts carbon nitride scaffolds alkyne semi-hydrogenation density functional theory metal–host interaction

How does the brown mussel perna perna respond to environmental pollution?A review on pollution biomarkers

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Journal of Environmental Sciences 2022年第1期34卷 412-428页

作者： Fernanda Silva dos Santos Raquel A.F.Neves Mirian Araújo Carlos Crapez Valéria Laneuville Teixeira Natascha Krepsky Fluminense Federal University(UFF) Institute of BiologyGraduate Program in Science and BiotechnologyMario Santos Braga Streets/n.CentroNiteróiRJ CEP 24.020-141Brazil Federal University of the State of Rio de Janeiro(UNIRIO) Institute of Biosciences(IBIO)Graduate Program in Neotropical Biodiversity(PPGBIO)Pasteur Avenue458.UrcaRio de JaneiroRJ CEP 22.290-255Brazil Fluminense Federal University(UFF) Institute of BiologyGraduate Program in Marine Biology and Coastal EnvironmentsMario Santos Braga Streets/n.CentroNiteróiRJ CEP 24.020-141Brazil Federal University of the State of Rio de Janeiro(UNIRIO) Institute of Biosciences(IBIO)Graduate Program in Ecotourism and ConservationPasteur Avenue458.UrcaRio de JaneiroRJ CEP 22.290-255Brazil

The brown mussel perna perna(Linnaeus,1758)is a valuable resource for aquaculture in tropical and subtropical coastal *** presents desirable characteristics for biomonitoring,including being sessile,widely distributed and abundant,and is a filter-feeder able to accumulate several classes of pollutants(e.g.,metals,hydrocarbons,among others).Mussels’biological responses to pollution exposure can be measured as biomarkers,which include alterations ranging from molecular to physiological levels,to estimate the degree of environmental contamination and its effects on *** full review compiles two decades(2000–2020)of literature concerning biological effects on *** mussel caused by environmental pollutants(i.e.,metals,hydrocarbons,and emerging pollutants),considering environmental and farm-based *** markers related to mussels’oxidative status were efficient for the biomonitoring of metals(i.e.,antioxidant enzymes associated with oxidative damage in biomolecules).Genotoxicity and cytotoxicity indicators(i.e.,comet,micronucleus,and neutral red assays)provided a depiction of hydrocarbon *** neutral red assay gave a time-concentration cytotoxic response to a wide range of pollutants,including emerging pollutants(e.g.,pharmaceuticals and biocides)and *** perna hemocyte parameters provided a useful approach for biocide *** paper summarizes useful biomarkers from molecular to physiological levels in this mussel species used to identify and quantify the degree of coastal *** integrated biomarker analysis may provide a way to overcome possible biomarker variations and assess multi-polluted ***,it is necessary to investigate biomarker variations according to natural factors(e.g.,season and gonad maturation stage)to standardize them for trustworthy biomonitoring.

关键词： Biological indexes Biomonitoring Emerging pollutants Hydrocarbons Metals Sentinel species