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Journal of Renewable Materials 2020年第6期8卷 675-686页

作者： Dragomir Vassilev Nadezhda Petkova Yulian Tumbarski milena.koleva.pa.teley denev Department of Physics Chemistry and EcologyTechnical University of GabrovoGabrovo5300Bulgaria Department of Inorganic and Organic Chemistry University of Food TechnologiesPlovdiv4002Bulgaria Department of Microbiology University of Food TechnologiesPlovdiv4002Bulgaria

Undenicylic acid(10:1)is known as an antifungal agent and an active ingredient of many topical medicines[1–6].The present research investigates the preparation of aliphatic esters of 10-undecylic acid with butanol and i-amyl alcohol by the conventional and ultrasound-assisted syntheses as well as the structural elucidation of the resulting compounds,by FTIR and NMR *** antimicrobial properties of the obtained 10-undecylenic esters were tested against Gram-positive bacteria(Staphylococcus aureus;Enterococcus faecalis;Listeria monocytogenes),Gram-negative bacteria(Escherichia coli;Salmonella sp.)and filamentous fungi(Penicillium sp.;Aspergillus niger;Fusarium moniliforme)using the conventional agar-well diffusion *** results demonstrated that all esters had insignificant antibacterial activity.i-Amyl-10-undecylenate and t-butyl-10-undecylenate showed activity against both Gram-positive and Gram-negative bacteria,while i-butyl-10-undecylenate and n-butyl-10-undecylenate were effective only against Gram-positive bacteria *** contrast,all 10-undecylenic esters demonstrated high antifungal activity,which was most pronounced in ***,the obtained products can be successfully used as promising antifungal agents for various pharmaceutical formulations as well as biocontrol means against plant pathogens.

关键词： 10-undecylenate alkyl esters FTIR and NMR spectroscopy antimicrobial activity

Microwave-Assisted Isolation and Acetylation of Inulin from Helianthus Tuberosus L Tubers

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Journal of Renewable Materials 2018年第7期6卷 671-679页

作者： Nadezhda Petkova Gergana Gencheva Dragomir Vassilev milena koleva Albert Krastanov panteley denev Department of Organic Chemistry and Inorganic Chemistry University of Food Technologies26 Maritza Blvd.Plovdiv4002Bulgaria Department Physics Chemistry and EcologyTechnical University of GabrovoGabrovo5300Bulgaria Department of Biotechnology University of Food Technologies26 Maritza Blvd.Plovdiv4002Bulgaria

Jerusalem artichoke (Helianthus tuberosus L.) tubers are industrial crop considered as a promising source forinulin production. “Green” method was performed for accelerated inulin extraction from Helianthus tuberosus *** by the application of microwave irradiation. Further pretreatment of the water extract with acetone andethanol yielded inulin (20%) with purity 89% and degree of polymerization 18. Jerusalem artichoke inulin wascharacterized by FTIR and NMR spectroscopy. For the first time eco-friendly synthesis of acetylated Jerusalemartichoke inulin was performed by the reaction with acetic anhydride, without toxic solvent, but only withsodium acetate as catalyst under microwave irradiation for 60 s. The degree of acetylation (DA=2.1) and thestructure of inulin esters were confirmed by 1H and 13C NMR. The suggested microwave acetylation shortenssignificantly the esterification reaction.

关键词： Jerusalem artichoke inulin inulin acetates microwave irradiation

Physicochemical Characterization and Antimicrobial Properties of Inulin Acetate Obtained by Microwave-Assisted Synthesis

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Journal of Renewable Materials 2020年第4期8卷 365-381页

作者： Nadezhda Petkova Radka Arabadzhieva Dragomir Vassilev Gergana Gencheva Yulian Tumbarski Tsveteslava Ignatova-Ivanova Sevginar Ibryamova Mina Todorova milena.koleva.pa.teley denev Department of Organic Chemistry and Inorganic Chemistry University of Food TechnologiesPlovdiv4002Bulgaria Department of Physics Chemistry and EcologyTechnical University of GabrovoGabrovo5300Bulgaria Department of Microbiology University of Food TechnologiesPlovdiv4002Bulgaria Department of Biology Konstantin Preslavsky University of ShumenShumenBulgaria

Microwave-assisted irradiation was performed for esterification of chicory inulin with high degree of polymerization with acetic anhydride without a solvent only with a *** resulting esters were characterized by melting point,hydrophilic-lipophilic balance,thin-layer chromatography,ultraviolet spectroscopy,Fourier transform infrared spectroscopy(FTIR)and nuclear magnetic resonance(NMR)*** acetate demonstrated a high degree of acetylation(2.5-3.0)and presented a white,water-insoluble substance with bitter *** FTIR and NMR spectra confirmed esterification and demonstrated the incorporation of hydrophobic residue to the water soluble inulin *** capacity,water holding,oil-holding capacities,the foamability,foam stability and emulsifying properties were also *** acetate showed promising foam stability 52%for 60 min and formed stable emulsions at concentration 0.2 g/L with 50 and 80%oil *** water holding capacity was lower than the oil holding *** addition to this,for the first time,the antimicrobial potential of inulin acetate was tested against seventeen microorganisms(Gram-positive and Gram-negative bacteria,yeasts and fungi).Inulin acetate(10 mg/ml)inhibited the growth of Bacillus cereus,Escherichia coli ATCC 8739,Salmonella abony,Candida albicans and Penicillium ***,inulin acetate demonstrated antimicrobial activity at concentration 1 mg/ml against Listeria monocytogenes 863,Escherichia coli 3398,Candida albicans 8673,Fusarium oxysporum and Aspergillus *** current study demonstrated the applications of“green”synthesized inulin acetate as a foaming agent,oil-in-water emulsion stabilizer and antimicrobial substance in pharmaceutical,agricultural and cosmetic preparations.

关键词： Inulin acetates microwave irradiation FTIR and NMR spectroscopy foams emulsions antimicrobial activity

Treatment of spinal cord injury with biomaterials and stem cell therapy in non-human primates and humans

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Neural Regeneration Research 2025年第2期20卷 343-353页

作者： Ana milena Silva Olaya Fernanda Martins Almeida Ana Maria Blanco Martinez Suelen Adriani Marques PhD Program in pathological Anatomy Federal University of Rio de JaneiroRio de JaneiroBrazil Biomedical Science Institute Federal University of Rio de JaneiroRio de JaneiroBrazil Graduate Program in pathological Anatomy Federal University of Rio de JaneiroRio de JaneiroBrazil Graduate Program in pathological Anatomy(PPGAP/UFRJ) Department of Neurobiology/Institute of BiologyCampus do GragoatáNiteróiRio de JaneiroBrazil

Spinal cord injury results in the loss of sensory,motor,and autonomic functions,which almost always produces permanent physical ***,in the search for more effective treatments than those already applied for years,which are not entirely efficient,researches have been able to demonstrate the potential of biological strategies using biomaterials to tissue manufacturing through bioengineering and stem cell therapy as a neuroregenerative approach,seeking to promote neuronal recovery after spinal cord *** of these strategies has been developed and meticulously evaluated in several animal models with the aim of analyzing the potential of interventions for neuronal repair and,consequently,boosting functional *** the majority of experimental research has been conducted in rodents,there is increasing recognition of the importance,and need,of evaluating the safety and efficacy of these interventions in non-human primates before moving to clinical trials involving therapies potentially promising in *** article is a literature review from databases(PubMed,Science Direct,Elsevier,Scielo,Redalyc,Cochrane,and NCBI)from 10 years ago to date,using keywords(spinal cord injury,cell therapy,non-human primates,humans,and bioengineering in spinal cord injury).From 110 retrieved articles,after two selection rounds based on inclusion and exclusion criteria,21 articles were ***,this review arises from the need to recognize the experimental therapeutic advances applied in non-human primates and even humans,aimed at deepening these strategies and identifying the advantages and influence of the results on extrapolation for clinical applicability in humans.

关键词： bioengineering biomaterials cell therapy humans non-human primates spinal cord injury stem cell therapy

Microwave Synthesis of Inulin Acetate as Potential Bio- Based Additive for Poly(Vinyl Chloride)

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Journal of Renewable Materials 2018年第7期6卷 707-714页

作者： D.Vassilev N.Petkova M.koleva P.denev Department“Physics Chemistry and Ecology”Technical University of Gabrovo4 Hadji Dimitar str.5300 GabrovoBulgaria Department of Organic Chemistry and Inorganic Chemistry University of Food Technologies26 Maritza blv.4002 PlovdivBulgaria

The paper presents the findings of an experimental study on the microwave synthesis (MW) of inulin acetateand its possible application as bio-additive in poly(vinyl chloride) (PVC). The obtained inulin acetate has beenidentified and characterized by spectroscopic methods. Advantages of the MW compared with the conventionalsynthesis were defined. In order to evaluate possible application of the product as bio-based additive forpolymers, effect of the inulin ester on PVC behavior and characteristics has been investigated by differentialscanning calorimetry (DSC) and deformation upon extension. Experimental results show that in concentrationrange up to 30.0 wt. % the inulin ester influences positively the properties of PVC causing effect similar toplasticizing one. At concentration over 30 wt.% the ester shows more specific behavior, which will be furtherinvestigated. Conclusions about potential application of MW synthesized inulin acetate as bio-based additive forPVC have been drawn.

关键词： Inulin esters microwave-assisted esterification poly(vinyl chloride) bio-based additive tensile properties

Outsmarting SARS-CoV-2 by empowering a decoy ACE2

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Signal Transduction and Targeted Therapy 2020年第1期5卷 305-307页

作者： milena Sokolowska Swiss Institute of Allergy and Asthma Research(SIAF) University of ZurichDavosSwitzerland Christine Kühne-Center for Allergy Research and Education(CK-CARE) DavosSwitzerland

Along with the current efforts to develop high-affinity neutralizing antibodies,Chan and colleagues engineered the soluble variant of human ACE2 with enhanced binding to the spike protein,outranking the soluble wild-type protein in blocking SARS-CoV-2 infection in *** addition,the newly created soluble ACE2 is enzymatically active in cleaving angiotensin-2,increasing its therapeutic potential in COVID-19.

关键词： ACE2 decoy smart

Mechanochemical Synthesis and Characterization of Nanocrystalline Copper-Cobalt Ferrites

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 367-372页

作者： Nikolay Velinov Dimitar Dimitrov Kremena koleva Krassimir Ivanov Ivan Mitov Institute of Catalysis Bulgarian Academy of Sciences Department of Chemistry Agricultural University

Nanocrystalline copper-cobalt ferrites with composition Cu_（1-x）Co_xFe_2O_4,where x = 0.2 and 0.8,were synthesized by mechanochemical treatment of co-precipitated *** ferrite powders were characterized by XRD and Mossbauer *** proved obtaining of spinel ferrites with crystallite size smaller than 10 *** of crystallite size of samples with increasing of mechanochemical treatment duration was established,*** properties of obtained ferrites were tested in reactions of oxidation of CO,methanol and dimethyl *** catalytic activity of nanocrystalline copper-cobalt ferrites toward CO and CH_3OH（about 100% conversions of CO and CH_3OH at 160 ℃）and moderate activity toward（CH_3）_2O oxidation were *** results obtained revealed that the Co/Cu atomic ratio is an important factor determinant the behavior of catalysts toward methanol and DME oxidation.

关键词： Mechanochemical synthesis Nanocrystalline Ferrites Mossbauer spectroscopy Catalysis

Colorectal cancer mortality trends in Serbia during 1991–2010:an age-period-cohort analysis and a joinpoint regression analysis

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Chinese Journal of Cancer 2016年第10期35卷 518-527页

作者： milena Ilic Irena Ilic Department of Epidemiology Faculty of Medical SciencesUniversity of Kragujevac Faculty of Medical Sciences University of Kragujevac

Background: For both men and women worldwide, colorectal cancer is among the leading causes of cancer-related death. This study aimed to assess the mortality trends of colorectal cancer in Serbia between 1991 and 2010, prior to the introduction of population-based ***: Joinpoint regression analysis was used to estimate average annual percent change(AAPC) with the corresponding 95% confidence interval(CI). Furthermore, age-period-cohort analysis was performed to examine the effects of birth cohort and calendar period on the observed temporal ***: We observed a significantly increased trend in colorectal cancer mortality in Serbia during the study period(AAPC = 1.6%, 95% CI 1.3%–1.8%). Colorectal cancer showed an increased mortality trend in both men(AAPC –2.2%) and women(AAPC rend of colorectal cancer mo= 2.0%, 95% CI 1.7%= 1.0%, 95% CI 0.6%–1.4%). The temporal trtality was significantly affected by birth cohort(P parability test, overall mortality trends for colon cancer and rectal and anal cancer were not parallel(the final selected model rejected parallelism, P past two decades. Mortality increased particularly in men, but the trends were different according to age group and subsite. In Serbia, interventions to reduce colorectal cancer burden, especially the implementation of a national screening program, as well as treatment improvements and measures to encourage the adoption of a healthy lifestyle, are needed.

关键词：塞尔维亚队列分析结直肠癌回归分析死亡率连接点龄期大肠癌

Engineering-Geological Problems in the Moravian Karst,Czech Republic

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Acta Geologica Sinica(English Edition) 2001年第3期75卷 303-307页

作者： milena AMALIKOVA Duke Engineering & Services Sumavska 35658 56 Brno Czech Republic

The Moravian karst belongs to one of the famous karst regions in Central Europe. It is situated in Moravia in the eastern part of the Czech Republic. According to the geology it is of Devonian age and the main rocks are of different types of limestones. The process of karstification is still active. They are many caves with rich stalagmites and stalactites and the Macocha abyss, the depth of which is 138.5 m. The underground Punkva River flows through the main part of the karst, forming beautiful underground lakes. Typical karst phenomena, such as sinkholes and deep canyons, may be observed on the surface of the terrain. Because of the karstification, water erosion and frost weathering, many steep unstable slopes and walls originated. To solve the stability from a geotechnical point of view is not easy. This requests a special engineering-geological knowledge and experience.

关键词： Czech Republic Moravian karst engineering geology slope stability long-term monitoring

Epidemiology of stomach cancer

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World Journal of Gastroenterology 2022年第12期28卷 1187-1203页

作者： milena Ilic Irena Ilic Department of Epidemiology Faculty of Medical SciencesUniversity of KragujevacKragujevac 34000Serbia Faculty of Medicine University of BelgradeBelgrade 11000Serbia

Despite a decline in incidence and mortality during the last decades,stomach cancer is one of the main health challenges *** to the GLOBOCAN 2020 estimates,stomach cancer caused approximately 800000 deaths(accounting for 7.7%of all cancer deaths),and ranks as the fourth leading cause of cancer deaths in both genders *** 1.1 million new cases of stomach cancer were diagnosed in 2020(accounting for 5.6%of all cancer cases).About 75%of all new cases and all deaths from stomach cancer are reported in *** cancer is one of the most lethal malignant tumors,with a five-year survival rate of around 20%.There are some well-established risk factors for stomach cancer:Helicobacter pylori infection,dietary factors,tobacco,obesity,and *** date,the most important way of preventing stomach cancer is reduced exposure to risk factors,as well as screening and early *** research on risk factors can help identify various opportunities for more effective *** programs for stomach cancer have been implemented in a few countries,either as a national or opportunistic screening of high-risk individuals ***,due to its high aggressiveness and heterogeneity,stomach cancer still remains a severe global health problem.

关键词： Stomach cancer Epidemiology Incidence Mortality Survival Predictive factors Prevention