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1.
Int J Biol Macromol ; 106: 1192-1202, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28851644

RESUMO

Loomstate-, scoured- and bleached cotton fabrics were first activated by treatment with ethanolamine and; thus obtained three fabrics were submitted independently to in-situ formation of silver nanoparticles (AgNPs) using different concentrations of silver nitrate (AgNO3) in absence of other external precursor. The magnitude of AgNPs on the fabric increases by increasing AgNO3 concentrations during synthesis of AgNPs loaded fabrics irrespective of the fabric used. Loomstate- and scoured cotton fabrics with the highest amount of AgNPs exhibit spherical shape with less aggregates; opposite to their bleached mate where AgNPs are irregularly shaped with bigger size due to aggregation. The formation of AgNPs is confirmed through monitoring UV-vis absorption peak. Results signify also the formation of high density coating of silver on the surface of cotton fabric. Fabrics loaded with AgNPs exhibit superior antibacterial activity. Treatment with distilled water of AgNPs loaded scoured cotton fabric filtered by centrifugation verify the very slow launching of AgNPs indicating excellent durability; a point which advocates the use of such fabrics in infection prevention applications. Indeed, the basic and practice entailed in current studies can be nominated strongly for cleaner bactericidal finishing of cotton.


Assuntos
Antibacterianos/química , Infecções Bacterianas/prevenção & controle , Fibra de Algodão , Nanopartículas Metálicas/química , Antibacterianos/síntese química , Infecções Bacterianas/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Etanolamina/química , Humanos , Nanopartículas Metálicas/microbiologia , Prata/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Têxteis/microbiologia
2.
Carbohydr Polym ; 181: 307-316, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29253977

RESUMO

In situ formation of zinc oxide nanoparticles (ZnO-NPs) was studied within the framework of several factors. variables examined include (i) innovation of a new capping agent; (ii) nature of the cotton fabric related to its processing; (iii) formation of Zinc hydroxide (Zn(OH)2) due to reduction of zinc acetate with sodium hydroxide (iv) treatment of the differently processed cotton fabrics with (Zn(OH)2) functionalized dispersion as per the exhaustion method, (v) further treatment of the cotton fabrics with (Zn(OH)2) dispersion according to the pad-dry-cure method and (Vi) conversion of (Zn(OH)2) to ZnO-NPs during the curing step in the latter method. Results depict that the incorporation of the bio-extract obtained from date seed waste works effectively as capping material which stabilize ZnO-NPs. Mercerized bleached cotton fabric proves to be a better candidate than mercerized loomstate cotton fabric in conferring sustainable bactericidal and UV blocking.

3.
Carbohydr Polym ; 178: 251-259, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29050591

RESUMO

The research work presented herein was undertaken with a view to develop, characterize and highlight modified cotton fabrics that acquire durable antibacterial activity in concomitant with high metal sorption capacity. The development is based on reacting cotton cellulose previously oxidized by sodium periodate-with 4 amino-1,2,4 triazole in presence and absence of silver nano particles (AgNPs). The idea behind the periodate pretreatment is to convert (via oxidative cleavge) the 2,3-vicinal diol of the anhydroglucose units of cotton into aldehyde groups. The latter are easily reacting with the triazole groups in the modified cotton. On the other hand AgNPs were fabricated as per the reduction method using bio-material extracted from the root of licorice. By virtue of its reducing action, the bio-material converts Ag+ ions to Ag0 atom which is also stabilized Ag the bio-material in the form of cluster which is the agregate of about 5 Ag0. The clusters are cropped with the stabilizer thus forming silver nanoparticles. Measurement of the particle size displays a value of 8.7nm. Charactrisation of triazole treated cotton fabrics reveals the presence of the triazole moieties inside the structure of cotton. Furthermore, Fabrictreated with triazole in presence and absence of AgNPs exhibits a relatively high antibacterial activity against gram-negative tested bacteria (E. coli) as compared to that of gram-positive tested bacteria (S. aureus). The metal sorption of triazole treated cotton fabrics was higher than those of untreated or periodate pretreated fabric due to the increase in nitrogen centers created along the cellulose chains. Experimental data were accomplished through Langmuir, Freundlich and Temkin sorption isotherm models. It was shown that sorption follows Langmuir isotherm model and suggests that the innovative fabric in question can adsorb metal ions from polluted dye bath.


Assuntos
Antibacterianos/química , Fibra de Algodão , Nanopartículas Metálicas/química , Ácido Periódico/química , Prata , Triazóis/química , Celulose/química , Escherichia coli , Oxirredução , Staphylococcus aureus , Têxteis
4.
Int J Oncol ; 15(4): 757-67, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10493959

RESUMO

This work was designed with the purpose of determining whether the presence of allelic imbalances (AI) such as microsatellite instability (MSI) and loss of heterozygosity (LOH) in chromosomes 2, 11, 13, and 17 in primary breast cancer could be used as prognostic indicators of patient survival. The DNA from breast cancers removed from 29 patients who were followed-up for up to five years was analyzed for MSI and LOH using a panel of 24 markers located at chromosome 2 (TPO, D2S131, D2S144, D2S171, D2S177, D2S119, D2S123, D2S147 and D2S136), chromosome 11 (C-RAS, Int-2, D11S940, D11S912), chromosome 13 (D13S289, D13S260, D13S267, D13S218, D13S263, D13S155, and D13S162), and chromosome 17 (D17S513, TP53, D17S855, and D17S785). The frequency of AI in the markers studied ranged from 30-55%, being highest for D11S912, D2S171, TP53 and D17S855. Univariate analysis showed association between overall survival rate and AI in 9 out of the 24 markers tested. Five of them were located at the area of the mismatch repair gene (MMR)-2 gene, two at 11p, one at 13q and one at 17p. Using multivariate analysis, it was observed that only pathological and clinical stage (defined as stage II or not) and AI at D2S171, D11S912, or D17STP53 generated significant predictive models for survival.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Perda de Heterozigosidade/genética , Adulto , Neoplasias da Mama/diagnóstico , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 2 , Feminino , Seguimentos , Humanos , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Polimorfismo Genético/genética , Prognóstico , Modelos de Riscos Proporcionais , Taxa de Sobrevida
5.
Pharmacol Res ; 39(4): 289-95, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10208759

RESUMO

Biopharmacological evaluations of the protective effects of L-carnitine (a naturally occurring quaternary ammonium compound) against doxorubicin-induced metabolic damage were carried out in isolated cardiac myocytes and in isolated rat heart mitochondria. Perfusion of the heart with DOX (0.5 mM) caused a significant 70% inhibition of palmitate oxidation in cardiac myocytes, while L-carnitine (5 mM) perfusion caused stimulation which accounted for 37%. Perfusion of the heart with L-carnitine after 10-min perfusion with DOX (0.5 mM) caused 88% reversal of DOX-induced inhibition of palmitate oxidation in cardiac cells. In rat heart mitochondria, DOX has no effect on either palmitate oxidation or acyl-CoA synthetase activity, whereas Enoximone (c-AMP-dependent phosphodiesterase inhibitor), caused a significant inhibition of palmitate oxidation and acyl-CoA activity (40 and 27%, respectively). The oxidation of palmitoyl-CoA, an index of carnitine palmitoyltransferse reaction was significantly inhibited by DOX as a function of DOX concentration. Preincubation of mitochondria with L-carnitine caused reversal of DOX-induced inhibition of palmitoyl-CoA oxidation depending on the concentration of L-carnitine. Moreover, L-carnitine treatment did not interfere with the cytotoxic effect of doxorubicin against the growth of solid Ehrlich carcinoma. The findings of this study may suggest that inhibition of fatty acid oxidation in the heart is at least a part of doxorubicin cardiotoxicity and that L-carnitine can be used to prevent the doxorubcin-induced cardiac metabolic damage without interfering with its antitumour activities.


Assuntos
Antineoplásicos/toxicidade , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/metabolismo , Carnitina/farmacologia , Doxorrubicina/toxicidade , Animais , Antineoplásicos/antagonistas & inibidores , Antineoplásicos/farmacologia , Carcinoma de Ehrlich/tratamento farmacológico , Carcinoma de Ehrlich/patologia , Cardiomiopatias/induzido quimicamente , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Doxorrubicina/antagonistas & inibidores , Doxorrubicina/farmacologia , Feminino , Técnicas In Vitro , Masculino , Camundongos , Oxirredução , Ácido Palmítico/metabolismo , Ratos , Ratos Sprague-Dawley
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