79 research outputs found

    ANTIOXIDANT ACTIVITY OF LEAF EXTRACTS OF HEMIDESMUS INDICUS (L.) R.BR. (ASCLEPIADACEAE).

    Get PDF
    Objective: A number of Indian medicinal plants have been used for thousands of years in a traditional system of medicine. Hemidesmus indicus is an important member of the Asclepiadaceae family. It is an endemic to the southern Western Ghats, India. The aim of the study was to investigate the free radical scavenging activity of H. indicus. Methods: The aqueous and methanol leaf extracts of H. indicus were assayed for radical scavenging activity, using the stable free radical 2,2-diphenyl- 1-picryl-hydrazyl-hydrate and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid). Results: The results revealed that the IC50 values of aqueous extract of H. indicus were found to be higher than that of the other solvent extracts. The free radical scavenging activity of the plant extracts may be due to the presence of phytoconstituents. Conclusion: In all the methods, the aqueous extract has exhibited the good scavenging activity and this arises that the plant has a potential antioxidant agent

    Evaluating Ultrasonogram Guided Jugular Venous Cannulation Transducer Views

    Get PDF
    BACKGROUND: The aim of the study is to evaluate and weigh the pros and cons of three different transducer views, short, long and oblique axis in ultrasonogram guided internal jugular venous cannulation in patients posted for cardio thoracic surgeries. METHOD: A total of 150 ASA PS-II patients of various sex, age above 18 years were divided into three grous n=50 short , n=50 long and n=50 oblique. The first needle pass succes rate, number of needle passes, cannulation time in seconds, mechanical complications like posterior venous wall puncture, carotid artery puncture and hematoma formation are measured for all the patients . RESULTS: On analysis, in view of first needle pass success rate, edle pass succes rate, number of needle passes, cannulation time in seconds, oblique axis and short axis is better than long axis. In view of posterior venous wall puncture, oblique and long axis is better than short axis. oblique and short axis has lower carotid artery puncture and hematoma formation than long axis. CONCLUSION: From above statistical study ,after weighing the pros and cons of three transducer views of ultrasound guided internal jugular venous cannulation in cardiothoracic surgical patients, it is concluded that oblique axis is predecessor to short and long axis by taking first needle pass success rate, number of needle passes, cannulation time in seconds and reduced complications into account

    Directional Freeze-Casting : A Bioinspired Method to Assemble Multifunctional Aligned Porous Structures for Advanced Applications

    Get PDF
    Herein, the potential of directional freeze-casting techniques as a very generic, green, and straightforward approach for the processing of various functional porous materials is introduced. These materials include 3D monoliths, films, fibers, and microspheres/beads, which are obtained by the assembly of network building blocks originated from cryoassembly of the various aqueous-based systems. The process simply relies on 1) directional freezing of the slurry through contact with a cold surface, 2) maintaining the slurry at the frozen state for a particular time with controlling the freezing parameters and directions, and 3) sublimation of the created ice crystal templates inside the developed structure to translate the ice growth pattern to final porous structure. The materials developed with such a cryogenic process contain a highly complex porous structure, e.g., a hierarchical and well-aligned microstructure in different levels, which renders a high control over the physicochemical and mechanical functionalities. Due to the versatility and controllability of this technique, the process can also be extended for the mimicking of the structures found in natural materials to the bulk materials to assemble bioinspired porous composites with many useful mechanical and physical features. The aim, herein, is to give a brief overview of the recent advances in developing anisotropic porous inorganic, organic, hybrid, and carbonaceous materials with a particular emphasis on materials with biomimicking microstructure using directional ice templating approach and to highlight their recent breakthrough for different high-performance applications.Peer reviewe

    Effect of compatibilizers on lignin/bio-polyamide blend carbon precursor filament properties and their potential for thermostabilisation and carbonisation

    Get PDF
    Biobased blends from hydroxypropyl modified lignin (TcC) and a biobased polyamide (PA1010) were produced by continuous sub-pilot scale melt spinning process. A reactive compatibilization was employed with the help of two different compatibilizers (ethylene-acrylic ester-maleic anhydride (MA) and ethylene-methyl acrylate-glycidyl methacrylate (GMA)) to enhance the compatibility between the TcC and PA1010. The enhanced compatibility between the TcC and PA1010 achieved by reaction between hydroxyl groups with maleic anhydride groups in the MA compatibilizer or epoxy groups in the GMA compatibilizer via nucleophilic substitution, was confirmed by chemical (Fourier infrared measurements), physical (glass transition, melting and crystallization behaviour), rheological, morphological and tensile properties of the filaments from compatibilized blends. MA compatibilizer required a higher concentration (2 phr) than GMA (1 phr) to achieve an optimal performance because of the difference in the reactive group's concentration within the each compatibilizer. The MA compatibilizer though was more effective than GMA. The precursor blended filaments were successfully carbonized in a lab scale experiment to yield coherent carbon fibres with tensile stress values of 192 ± 77 and 159 ± 95 MPa; and moduli of 16.2 and 13.9 GPa respectively for uncompatibilised and 2% MA compatibilized blends. That the compatibilized carbon fibre properties are slightly inferior may be attributed to the need to accurately control and optimise applied stress during the thermostabilisation and carbonization stages. Notwithstanding, these differences, the results indicate the potential benefit of using compatibilized TcC/PA1010 blend filaments as carbon fibre precursors

    Zika virus infection induces endoplasmic reticulum stress and apoptosis in placental trophoblasts

    Get PDF
    Zika virus (ZIKV) infection to a pregnant woman can be vertically transmitted to the fetus via the placenta leading to Congenital Zika syndrome. This is characterized by microcephaly, retinal defects, and intrauterine growth retardation. ZIKV induces placental trophoblast apoptosis leading to severe abnormalities in the growth and development of the fetus. However, the molecular mechanism behind ZIKV-induced apoptosis in placental trophoblasts remains unclear. We hypothesize that ZIKV infection induces endoplasmic reticulum (ER) stress in the trophoblasts, and sustained ER stress results in apoptosis. HTR-8 (HTR-8/SVneo), a human normal immortalized trophoblast cell and human choriocarcinoma-derived cell lines (JEG-3 and JAR) were infected with ZIKV. Biochemical and structural markers of apoptosis like caspase 3/7 activity and percent apoptotic nuclear morphological changes, respectively were assessed. ZIKV infection in placental trophoblasts showed an increase in the levels of CHOP mRNA and protein expression, which is an inducer of apoptosis. Next, we also observed increased levels of ER stress markers such as phosphorylated forms of inositol-requiring transmembrane kinase/endoribonuclease 1α (P-IRE1α), and its downstream target, the spliced form of XBP1 mRNA, phosphorylated eukaryotic initiation factor 2α (P-eIF2α), and activation of cJun N-terminal Kinase (JNK) and p38 mitogen activated protein kinase (MAPK) after 16–24 h of ZIKV infection in trophoblasts. Inhibition of JNK or pan-caspases using small molecule inhibitors significantly prevented ZIKV-induced apoptosis in trophoblasts. Further, JNK inhibition also reduced XBP1 mRNA splicing and viral E protein staining in ZIKV infected cells. In conclusion, the mechanism of ZIKV-induced placental trophoblast apoptosis involves the activation of ER stress and JNK activation, and the inhibition of JNK dramatically prevents ZIKV-induced trophoblast apoptosis

    IN-VITRO ANTIMICROBIAL ACTIVITY OF BIOLOGICAL SYNTHESIZED SILVER NANOPARTICLES USING STENOTROPHOMONAS MALTOPHILIA STRAIN NS-24 FROM NON-RHIZOSPHERE SOIL

    Get PDF
    Objective: The present goals of our study were biological synthesis, characterizations of silver nanoparticles, and evaluation of its antimicrobial activity against microbial pathogens like Escherichia coli, Enterococcus faecalis, Streptococcus pneumoniae and Staphylococcus aureus. Methods: The bacterial Strain NS-24 was isolated on nutrient agar medium and was selected for the synthesis of silver nanoparticles based on its gram-negative characteristics. The characterizations of silver nanoparticles were done by UV-Visible spectroscopy, Atomic Force Microscopy (AFM), High Resolution-Transmission Electron Microscopy (HR-TEM), Scanning Electron Microscopy (SEM) with Energy Dispersive Spectroscopy (EDX), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). Later, the molecular characterization of the Strain NS-24 was done by DNA extraction and 16S rRNA gene sequencing. Results: The UV-visible spectrophotometric observation of the Strain NS-24 supernatant and AgNO3 solution showed maximum absorbance at 423 nm. The AFM data confirmed that the particles were polydispersed and spherical in shape. Additionally, the FTIR analysis revealed the IR spectral band patterning and TEM analyzes showed the size of biological AgNPs was in the range of 12.56 nm to 27.32 nm, with an average of 18.06 nm in size. Further, the 16S rRNA gene sequencing revealed the identity of Strain NS-24 as Stenotrophomonas maltophilia. The antimicrobial activity of AgNPs was studied on different gram-negative and gram-positive bacterial strains like Escherichia coli (MTCC 40), Enterococcus faecalis (MTCC 6845), Streptococcus pneumoniae (MTCC 8874) and Staphylococcus aureus (MTCC 2825), which showed good inhibition of their growth at varying concentrations of AgNPs against all the pathogens. Conclusion: Our findings showed that the synthesized AgNPs from the isolated bacterium was small in size and had profound antibacterial activity against pathogenic micro-organisms

    Omega-3 Fatty Acid-Derived Resolvin D2 Regulates Human Placental Vascular Smooth Muscle and Extravillous Trophoblast Activities

    Get PDF
    Omega-3 fatty acids are important to pregnancy and neonatal development and health. One mechanism by which omega-3 fatty acids exert their protective effects is through serving as substrates for the generation of specialized pro-resolving lipid mediators (SPM) that potently limit and resolve inflammatory processes. We recently identified that SPM levels are increased in maternal blood at delivery as compared to umbilical cord blood, suggesting the placenta as a potential site of action for maternal SPM. To explore this hypothesis, we obtained human placental samples and stained for the SPM resolvin D2 (RvD2) receptor GPR18 via immunohistochemistry. In so doing, we identified GPR18 expression in placental vascular smooth muscle and extravillous trophoblasts of the placental tissues. Using in vitro culturing, we confirmed expression of GPR18 in these cell types and further identified that stimulation with RvD2 led to significantly altered responsiveness (cytoskeletal changes and pro-inflammatory cytokine production) to lipopolysaccharide inflammatory stimulation in human umbilical artery smooth muscle cells and placental trophoblasts. Taken together, these findings establish a role for SPM actions in human placental tissue

    Omega-3 Fatty Acid-Derived Resolvin D2 Regulates Human Placental Vascular Smooth Muscle and Extravillous Trophoblast Activities

    Get PDF
    Omega-3 fatty acids are important to pregnancy and neonatal development and health. One mechanism by which omega-3 fatty acids exert their protective effects is through serving as substrates for the generation of specialized pro-resolving lipid mediators (SPM) that potently limit and resolve inflammatory processes. We recently identified that SPM levels are increased in maternal blood at delivery as compared to umbilical cord blood, suggesting the placenta as a potential site of action for maternal SPM. To explore this hypothesis, we obtained human placental samples and stained for the SPM resolvin D2 (RvD2) receptor GPR18 via immunohistochemistry. In so doing, we identified GPR18 expression in placental vascular smooth muscle and extravillous trophoblasts of the placental tissues. Using in vitro culturing, we confirmed expression of GPR18 in these cell types and further identified that stimulation with RvD2 led to significantly altered responsiveness (cytoskeletal changes and pro-inflammatory cytokine production) to lipopolysaccharide inflammatory stimulation in human umbilical artery smooth muscle cells and placental trophoblasts. Taken together, these findings establish a role for SPM actions in human placental tissue

    In Situ Compatibilization of Biopolymer Ternary Blends by Reactive Extrusion with Low-Functionality Epoxy-Based Styrene Acrylic Oligomer

    Full text link
    [EN] The present study reports on the use of low-functionality epoxy-based styrene¿acrylic oligomer (ESAO) to compatibilize immiscible ternary blends made of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), polylactide (PLA), and poly(butylene adipate-co-terephthalate) (PBAT). The addition during melt processing of low-functionality ESAO at two parts per hundred resin (phr) of biopolymer successfully changed the soften inclusion phase in the blend system to a thinner morphology, yielding biopolymer ternary blends with higher mechanical ductility and also improved oxygen barrier performance. The compatibilization achieved was ascribed to the in situ formation of a newly block terpolymer, i.e. PHBVb- PLA-b-PBAT, which was produced at the blend interface by the reaction of the multiple epoxy groups present in ESAO with the functional terminal groups of the biopolymers. This chemical reaction was mainly linear due to the inherently low functionality of ESAO and the more favorable reactivity of the epoxy groups with the carboxyl groups of the biopolymers, which avoided the formation of highly branched and/or cross-linked structures and thus facilitated the films processability. Therefore, the reactive blending of biopolymers at different mixing ratios with low-functionality ESAO represents a straightforward methodology to prepare sustainable plastics at industrial scale with different physical properties that can be of interest in, for instance, food packaging applications.This research was funded by the EU H2020 project YPACK (Reference number 773872) and by the Spanish Ministry of Science, Innovation, and Universities (MICIU) with project numbers MAT2017-84909-C2-2-R and AGL2015-63855-C2-1-R. L. Quiles-Carrillo wants to thank the Spanish Ministry of Education, Culture, and Sports (MECD) for financial support through his FPU Grant Number FPU15/03812. Torres-Giner also acknowledges the MICIU for his Juan de la Cierva contract (IJCI-2016-29675).Quiles-Carrillo, L.; Montanes, N.; Lagaron, J.; Balart, R.; Torres-Giner, S. (2019). In Situ Compatibilization of Biopolymer Ternary Blends by Reactive Extrusion with Low-Functionality Epoxy-Based Styrene Acrylic Oligomer. Journal of Polymers and the Environment. 27(1):84-96. https://doi.org/10.1007/s10924-018-1324-2S8496271Babu RP, O’Connor K, Seeram R (2013) Prog Biomater 2:8Torres-Giner S, Torres A, Ferrándiz M, Fombuena V, Balart R (2017) J Food Saf 37:e12348Quiles-Carrillo L, Montanes N, Boronat T, Balart R, Torres-Giner S (2017) Polym Test 61:421Zakharova E, Alla A, Martínez A, De Ilarduya S, Muñoz-Guerra (2015) RSC Adv 5:46395Steinbüchel A, Valentin HE (1995) FEMS Microbiol Lett 128:219McChalicher CWJ, Srienc F (2007) J Biotechnol 132:296Reis KC, Pereira J, Smith AC, Carvalho CWP, Wellner N, Yakimets I (2008) J Food Eng 89:361Vink ETH, Davies S (2015) Ind Biotechnol 11:167John RP, Nampoothiri KM, Pandey A (2006) Process Biochem 41:759Madhavan Nampoothiri K, Nair NR, John RP (2010) Biores Technol 101:8493Garlotta D (2001) J Polym Environ 9:63Lim LT, Auras R, Rubino M (2008) Prog Polym Sci 33:820Quiles-Carrillo L, Montanes N, Sammon C, Balart R, Torres-Giner S (2018) Ind Crops Prod 111:878Quiles-Carrillo L, Blanes-Martínez MM, Montanes N, Fenollar O, Torres-Giner S, Balart R (2018) Eur Polym J 98:402Witt U, Müller R-J, Deckwer W-D (1997) J Environ Polym Degrad 5:81Siegenthaler KO, Künkel A, Skupin G, Yamamoto M (2012) Ecoflex® and Ecovio®: biodegradable, performance-enabling plastics. In: Rieger B, Künkel A, Coates GW, Reichardt R, Dinjus E, Zevaco TA (eds) Synthetic biodegradable polymers. Springer, Berlin Heidelberg, p 91Jiang L, Wolcott MP, Zhang J (2006) Biomacromol 7:199Brandelero RPH, Yamashita F, Grossmann MVE (2010) Carbohyd Polym 82:1102Muthuraj R, Misra M, Mohanty AK (2014) J Polym Environ 22:336Porter RS, Wang L-H (1992) Polymer 33(10): 2019Koning C, Van Duin M, Pagnoulle C, Jerome R (1998) Prog Polym Sci 23:707Muthuraj R, Misra M, Mohanty AK (2017) J Appl Polym Sci 135:45726Ryan AJ (2002) Nat Mater 1:8Wu D, Zhang Y, Yuan L, Zhang M, Zhou W (2010) J Polym Sci Part B 48:756Kim CH, Cho KY, Choi EJ, Park JK (2000) J Appl Polym Sci 77:226Supthanyakul R, Kaabbuathong N, Chirachanchai S (2016) Polymer 105:1Na Y-H, He Y, Shuai X, Kikkawa Y, Doi Y, Inoue Y (2002) Biomacromolecules 3:1179Zeng J-B, Li K-A, Du A-K (2015) RSC Adv 5:32546Xanthos M, Dagli SS (1991) Polym Eng Sci 31:929Sundararaj U, Macosko CW (1995) Macromolecules 28:2647Milner ST, Xi H (1996) J Rheol 40:663Villalobos M, Awojulu A, Greeley T, Turco G, Deeter G (2006) Energy 31:3227Torres-Giner S, Montanes N, Boronat T, Quiles-Carrillo L, Balart R (2016) Eur Polym J 84:693Lehermeier HJ, Dorgan JR (2001) Polym Eng Sci 41:2172Liu B, Xu Q (2013) J Mater Sci Chem Eng 1:9Eslami H, Kamal MR (2013) J Appl Polym Sci 129:2418Loontjens T, Pauwels K, Derks F, Neilen M, Sham CK, Serné M (1997) J Appl Polym Sci 65:1813Ojijo V, Ray SS (2015) Polymer 80:1Frenz V, Scherzer D, Villalobos M, Awojulu AA, Edison M, Van Der Meer R (2008) Multifunctional polymers as chain extenders and compatibilizers for polycondensates and biopolymers. In: Technical papers, regional technical conference—society of plastics engineers, p. 3/1678Utracki LA (2002) Can J Chem Eng 80:1008Al-Itry R, Lamnawar K, Maazouz A (2012) Polym Degrad Stab 97:1898Lin S, Guo W, Chen C, Ma J, Wang B (2012) Mater Des (1980–2015) 36: 604Arruda LC, Magaton M, Bretas RES, Ueki MM (2015) Polym Test 43:27Wang Y, Fu C, Luo Y, Ruan C, Zhang Y, Fu Y (2010) J Wuhan Univ Technol Mater Sci Ed 25:774Wei D, Wang H, Xiao H, Zheng A, Yang Y (2015) Carbohyd Polym 123:275Abdelwahab MA, Taylor S, Misra M, Mohanty AK (2015) Macromol Mater Eng 300:299Sun Q, Mekonnen T, Misra M, Mohanty AK (2016) J Polym Environ 24:23Torres-Giner S, Gimeno-Alcañiz JV, Ocio MJ, Lagaron JM (2011) J Appl Polym Sci 122:914Miyata T, Masuko T (1998) Polymer 39:5515Muthuraj R, Misra M, Mohanty AK (2015) J Appl Polym Sci 132:42189Ren J, Fu H, Ren T, Yuan W (2009) Carbohyd Polym 77:576Torres-Giner S, Montanes N, Fenollar O, García-Sanoguera D, Balart R (2016) Mater Des 108:648Jamshidian M, Tehrany EA, Imran M, Jacquot M, Desobry S (2010) Compr Rev Food Sci Food Saf 9:552Savenkova L, Gercberga Z, Nikolaeva V, Dzene A, Bibers I, Kalnin M (2000) Process Biochem 35:573Costa ARM, Almeida TG, Silva SML, Carvalho LH, Canedo EL (2015) Polym Test 42:115Zhang K, Mohanty AK, Misra M (2012) ACS Appl Mater Interfaces 4:3091Zhang N, Wang Q, Ren J, Wang L (2009) J Mater Sci 44:250Chinsirikul W, Rojsatean J, Hararak B, Kerddonfag N, Aontee A, Jaieau K, Kumsang P, Sripethdee C (2015) Packag Technol Sci 28:741Auras R, Harte B, Selke S (2004) J Appl Polym Sci 92:1790Sanchez-Garcia MD, Gimenez E, Lagaron JM (2008) Carbohyd Polym 71:235Sanchez-Garcia MD, Gimenez E, Lagaron JM (2007) J Plast Film Sheeting 23:133Lagaron JM (2011) Multifunctional and nanoreinforced polymers for food packaging. In: Multifunctional and nanoreinforced polymers for food packaging. Woodhead Publishing, Cambridge, p 
    • …
    corecore