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1.
Sci Rep ; 14(1): 3137, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326474

RESUMO

In this study, a new nanocomposite was created by combining copper-doped nickel ferrite (NiCuFe2O4) nanoparticles with MCM-48 (Mobil Composition of Matter No. 48) on a graphene oxide (GO) substrate functionalized with poly(ρ-phenylenediamine) abbreviated as (PρPD). This nanocomposite was developed to investigate its potential for enhancing the function of a supercapacitor in energy storage. Following NiCuFe2O4@MCM-48 preparation, Hummer's technique GO was applied. In-situ polymerization of NiCuFe2O4@MCM-48/GO nanoparticles with ρ-phenylenediamine (ρPD) in the presence of ammonium persulfate (APS) produced PρPD, a conductive polymer. Structural characterization of the nanocomposite includes FTIR, XRD, VSM, TGA-DTG, EDX, and FE-SEM. Results from BET indicate a pore size increase of up to 5 nm. Fast ion penetration and higher storage in capacitor material are explained by this. Additionally, the nanocomposite's electrochemical performance was evaluated using GCD and CV tests. The NiCuFe2O4@MCM-48/GO/PρPD nanocomposite has a specific capacitance of 203.57 F g-1 (1 A g-1). Furthermore, cyclical stability is essential for energy storage applications. The nanocomposite retains 92.5% of its original capacitance after 3000 cycles, indicating outstanding electrochemical stability.

2.
Nanoscale Adv ; 6(2): 337-366, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38235087

RESUMO

Mechanical properties, such as elasticity modulus, tensile strength, elongation, hardness, density, creep, toughness, brittleness, durability, stiffness, creep rupture, corrosion and wear, a low coefficient of thermal expansion, and fatigue limit, are some of the most important features of a biomaterial in tissue engineering applications. Furthermore, the scaffolds used in tissue engineering must exhibit mechanical and biological behaviour close to the target tissue. Thus, a variety of materials has been studied for enhancing the mechanical performance of composites. Carbon-based nanostructures, such as graphene oxide (GO), reduced graphene oxide (rGO), carbon nanotubes (CNTs), fibrous carbon nanostructures, and nanodiamonds (NDs), have shown great potential for this purpose. This is owing to their biocompatibility, high chemical and physical stability, ease of functionalization, and numerous surface functional groups with the capability to form covalent bonds and electrostatic interactions with other components in the composite, thus significantly enhancing their mechanical properties. Considering the outstanding capabilities of carbon nanostructures in enhancing the mechanical properties of biocomposites and increasing their applicability in tissue engineering and the lack of comprehensive studies on their biosafety and role in increasing the mechanical behaviour of scaffolds, a comprehensive review on carbon nanostructures is provided in this study.

3.
Sci Rep ; 13(1): 16584, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789062

RESUMO

A novel catalyst was fabricated in this study based on zirconium MOF modified with pyridine carboxaldehyde in a solvothermal reaction, embedded with cerium. In order to confirm the catalyst structure, various characterization techniques, including FTIR, Far IR, EDX, XRD, TGA, FE-SEM, ICP, and BET analyses, were employed. The results indicated that the UiO-66-Pyca-Ce (III) catalyst had a Langmuir surface area of 501.63 m2/g, a pore volume of 0.28 cm3/g, and a pore size of 2.27 nm. To study catalytic activity, a sequential approach of Knoevenagel condensation and Michael addition was used to synthesize various polyhydroquinoline derivatives. The reaction took place at ambient temperature. The UiO-66-Pyca-Ce (III) catalyst demonstrated high efficacy (90%) and reusability in asymmetric synthesis of polyhydroquinoline derivatives for several reasons, including the possession of three Lewis acid activation functions.

4.
Colloids Surf B Biointerfaces ; 228: 113430, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37418814

RESUMO

Generally, hyperthermia is referred to the composites capability to increase local temperature in such a way that the generated heat would lead to cancerous or bacteria cells destruction, with minimum damage to normal tissue cells. Many different materials have been utilized for hyperthermia application via different heat generating methods. Carbon-based nanomaterials consisting of graphene oxide (GO), carbon nanotube (CNT), carbon dot (CD) and carbon quantum dot (CQD), nanodiamond (ND), fullerene and carbon fiber (CF), have been studied significantly for different applications including hyperthermia due to their biocompatibility, biodegradability, chemical and physical stability, thermal and electrical conductivity and in some cases photothermal conversion. Therefore, in this comprehensive review, a structure-based view on carbon nanomaterials application in hyperthermia therapy of cancer and bacteria via various methods such as optical, magnetic, ultrasonic and radiofrequency-induced hyperthermia is presented.


Assuntos
Hipertermia Induzida , Nanocompostos , Nanotubos de Carbono , Neoplasias , Humanos , Hipertermia Induzida/métodos , Neoplasias/terapia , Temperatura Alta
5.
Sci Rep ; 13(1): 9598, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37311979

RESUMO

Herein, a novel nanostructure based on cyclic aromatic polyimide with statistical star polymer structure was synthesized via the functionalization of the CuFe2O4 MNPs surface. The polymerization process on the functionalized surface of CuFe2O4 MNPs was performed with pyromellitic dianhydride and phenylenediamine derivatives. All analytical methods such as Fourier-transform infrared (FT-IR) spectroscopy, thermogravimetric (TG) analysis, X-ray diffraction (XRD) pattern, energy-dispersive X-ray (EDX), field-emission scanning electron microscope (FE-SEM), vibrating-sample magnetometer (VSM) were performed to characterize the structure of CuFe2O4@SiO2-polymer nanomagnetic. The cytotoxicity of CuFe2O4@SiO2-Polymer was investigated for biomedical application by MTT test. The results proved that this nanocmposite was biocompatible with HEK293T healthy cells. Also, the evaluation antibacterial property of CuFe2O4@SiO2-Polymer showed that its MIC in Gram-negative and Gram-positive bacteria were 500-1000 µg/mL, so it had antibacterial activity.

6.
Biomater Sci ; 10(24): 6911-6938, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36314845

RESUMO

A wound is defined as damage to the integrity of biological tissue, including skin, mucous membranes, and organ tissues. The treatment of these injuries is an important challenge for medical researchers. Various materials have been used for wound healing and dressing applications among which carbon nanomaterials have attracted significant attention due to their remarkable properties. In the present review, the latest studies on the application of carbon nanomaterials including graphene oxide (GO), reduced graphene oxide (rGO), carbon dots (CDs), carbon quantum dots (CQDs), carbon nanotubes (CNTs), carbon nanofibers (CNFs), and nanodiamonds (NDs) in wound dressing applications are evaluated. Also, a variety of carbon-based nanocomposites with advantages such as biocompatibility, hemocompatibility, reduced wound healing time, antibacterial properties, cell-adhesion, enhanced mechanical properties, and enhanced permeability to oxygen has been reported for the treatment of various wounds.


Assuntos
Nanotubos de Carbono
7.
Sci Rep ; 12(1): 15431, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104466

RESUMO

In this study, the main focus was on designing and synthesizing a novel magnetic nanobiocomposite and its application in hyperthermia cancer treatment. Regarding this aim, sodium alginate (SA) hydrogel with CaCl2 cross-linker formed and modified by silk fibroin (SF) natural polymer and halloysite nanotubes (HNTs), followed by in situ Fe3O4 magnetic nanoparticles preparation. No important differences were detected in red blood cells (RBCs) hemolysis, confirming the high blood compatibility of the treated erythrocytes with this nanobiocomposite. Moreover, the synthesized SA hydrogel/SF/HNTs/Fe3O4 nanobiocomposite does not demonstrate toxicity toward HEK293T normal cell line after 48 and 72 h. The anticancer property of SA hydrogel/SF/HNTs/Fe3O4 nanobiocomposites against breast cancer cell lines was corroborated. The magnetic saturation of the mentioned magnetic nanobiocomposite was 15.96 emu g-1. The specific absorption rate (SAR) was measured to be 22.3 W g-1 by applying an alternating magnetic field (AMF). This novel nanobiocomposite could perform efficiently in the magnetic fluid hyperthermia process, according to the obtained results.


Assuntos
Fibroínas , Hipertermia Induzida , Nanocompostos , Nanotubos , Alginatos , Argila , Células HEK293 , Humanos , Hidrogéis , Fenômenos Magnéticos , Nanocompostos/uso terapêutico
8.
Sci Rep ; 12(1): 10664, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35739165

RESUMO

By employing the naturally-originated molecule of creatine, Fe3O4@SiO2-creatine as an environmentally benign magnetic organometallic nanobiocatalyst was successfully prepared via a convenient and green route. Then to acquire an inclusive comprehension of different properties of the catalyst, it was studied by various characterization techniques such as FT-IR, FE-SEM, TEM, EDX, XRD, and VSM analyses. It was found that the size distribution of nanoparticles was an average diameter size of 70 nm. To examine the catalytic activity, it was applied in sequential knoevenagel condensation-Michael addition room temperature reaction of dimedone, malononitrile, and different substituted aromatic aldehydes to produce a variety of 2-amino-tetrahydro-4H-chromene-3-carbonitrile derivatives in a single step. Among the multiple outstanding advantages that can be mentioned for this work, some of the most noticeable ones include: affording the products in short reaction times with high yields, operating the reaction at ambient conditions and ease of catalyst separation.


Assuntos
Nanopartículas de Magnetita , Dióxido de Silício , Benzopiranos , Creatina , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Arq Gastroenterol ; 55(3): 279-282, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30540092

RESUMO

BACKGROUND: Helicobacter pylori (H. pylori) has been introduced by since 1983 by Marshal and Warren to play the main role in the pathophysiology of gastritis and gastric ulcers. Almost half of the world population1 is infected by H. pylori. Current therapeutic regimen against H. pylori includes the use of a proton pump inhibitor plus two or more antibiotics. However, the efficacy of this regimen is decreasing mainly due to antibiotic resistance and side effects of medications. This fact has resulted in public interest in other therapeutic options and the role of probiotics merits special attention in this regard. OBJECTIVE: This study aims to evaluate the efficacy of honey-derived Lactobacillus rhamnosus on H. pylori-induced gastric inflammation and gastro-intestinal infection in C57BL/6 Mice. METHODS: The 24 C57BL/6 Mice were randomly divided into three groups of eight mice each. All the mice were fed with 1cc suspension containing 5*1010 CFU/ mL of ATCC43504 strains of H. pylori for 3 consecutive days, twice daily via polyethylene gavage tubes. At the end of 4th week, infection with H. pylori was confirmed with stool Ag (ELISA) and following sacrifice of one mouse from each group, histopathologic study confirmed gastritis. The groups were subjected to different therapies as stated, 1: without Bismuth (Bi), Omeprazole (Om) and L. rhamnosus prescription, 2: Bi, Om and Clarithromycin (Cl) and 3: Bi, Om plus 1cc of suspension of 109 CFU/mL of L. rhamnosus. After 2 weeks, the stool was analyzed for Ag and the mice were sacrificed for evaluation of histopathologic changes. RESULTS: Treatment with L. rhamnosus group provided Zero titer of stool Ag and was associated with improved gastric inflammation in all subjects, similar to the clarithromycin group. CONCLUSION: Honey-derived L. rhamnosus probiotics provides similar results as clarithromycin in terms of improvement of H. pylori infection and gastritis in C57BL/6 Mice model, without its cons of antibiotic resistance.


Assuntos
Gastrite/terapia , Infecções por Helicobacter/terapia , Helicobacter pylori , Mel/microbiologia , Lacticaseibacillus rhamnosus , Probióticos/uso terapêutico , Animais , Antibacterianos/farmacologia , Claritromicina/farmacologia , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Gastrite/microbiologia , Infecções por Helicobacter/microbiologia , Masculino , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento
10.
Arq. gastroenterol ; 55(3): 279-282, July-Sept. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-973898

RESUMO

ABSTRACT BACKGROUND: Helicobacter pylori (H. pylori) has been introduced by since 1983 by Marshal and Warren to play the main role in the pathophysiology of gastritis and gastric ulcers. Almost half of the world population1 is infected by H. pylori. Current therapeutic regimen against H. pylori includes the use of a proton pump inhibitor plus two or more antibiotics. However, the efficacy of this regimen is decreasing mainly due to antibiotic resistance and side effects of medications. This fact has resulted in public interest in other therapeutic options and the role of probiotics merits special attention in this regard. OBJECTIVE: This study aims to evaluate the efficacy of honey-derived Lactobacillus rhamnosus on H. pylori-induced gastric inflammation and gastro-intestinal infection in C57BL/6 Mice. METHODS: The 24 C57BL/6 Mice were randomly divided into three groups of eight mice each. All the mice were fed with 1cc suspension containing 5*1010 CFU/ mL of ATCC43504 strains of H. pylori for 3 consecutive days, twice daily via polyethylene gavage tubes. At the end of 4th week, infection with H. pylori was confirmed with stool Ag (ELISA) and following sacrifice of one mouse from each group, histopathologic study confirmed gastritis. The groups were subjected to different therapies as stated, 1: without Bismuth (Bi), Omeprazole (Om) and L. rhamnosus prescription, 2: Bi, Om and Clarithromycin (Cl) and 3: Bi, Om plus 1cc of suspension of 109 CFU/mL of L. rhamnosus. After 2 weeks, the stool was analyzed for Ag and the mice were sacrificed for evaluation of histopathologic changes. RESULTS: Treatment with L. rhamnosus group provided Zero titer of stool Ag and was associated with improved gastric inflammation in all subjects, similar to the clarithromycin group. CONCLUSION: Honey-derived L. rhamnosus probiotics provides similar results as clarithromycin in terms of improvement of H. pylori infection and gastritis in C57BL/6 Mice model, without its cons of antibiotic resistance.


RESUMO CONTEXTO: O Helicobacter pylori (H. pylori) foi reconhecido em 1983 por Marechal e Warren como protagonista principal na fisiopatologia de gastrite e úlceras gástricas. Quase metade da população mundial está infectada por H. pylori. O regime terapêutico atual contra H. pylori inclui o uso de um inibidor da bomba de prótons associada a dois ou mais antibióticos. No entanto, a eficácia deste regime está diminuindo principalmente devido à resistência aos antibióticos e efeitos colaterais de medicamentos. Este fato resultou no interesse público em outras opções terapêuticas e o papel dos probióticos merece atenção especial a este respeito. OBJETIVO: Este estudo visa avaliar a eficácia do mel-derivado do Lactobacillus rhamnosus na inflamação gástrica e infecção gastrointestinal H. pylori-induzida em camundongos C57Bl/6. MÉTODOS: Vinte e quatro camundongos C57Bl/6 foram divididos aleatoriamente em três grupos de oito camundongos cada. Todos os ratos foram alimentados com suspensão de 1cc contendo 5*1010 UFC/mL de cepas ATCC43504 de H. pylori por 3 dias consecutivos, duas vezes por dia através de gavagem por tubos de polietileno. No final da 4ª semana, a infecção com H. pylori foi confirmada pelo antígeno fecal (ELISA) e após o sacrifício de um rato de cada grupo, o estudo histopatológico confirmou gastrite. Os grupos foram submetidos a diferentes terapias, como indicado, 1: sem prescrição de bismuto (BI), Omeprazol (Om) e L. rhamnosus, 2: Bi, Om e claritromicina (CL) e 3: Bi, Om mais 1cc de suspensão de 109 UFC/mL de L. rhamnosus. Após 2 semanas, as fezes foram analisadas para o antígeno e os ratos foram sacrificados para a avaliação das alterações histopatológicas. RESULTADOS: O tratamento com o grupo L. rhamnosus forneceu o título zero de antígeno e foi associado com a inflamação gástrica melhorada em todos os camundongos, similar ao grupo claritromicina. CONCLUSÃO: O probiótico mel-derivado L. rhamnosus fornece resultados semelhantes ao da claritromicina em termos de melhoria da infecção H. pylori e gastrite em C57Bl/6 camundongos modelos, sem os inconvenientes de resistência aos antibióticos.


Assuntos
Animais , Masculino , Helicobacter pylori , Infecções por Helicobacter/terapia , Probióticos/uso terapêutico , Lacticaseibacillus rhamnosus , Gastrite/terapia , Mel/microbiologia , Fatores de Tempo , Ensaio de Imunoadsorção Enzimática , Contagem de Colônia Microbiana , Distribuição Aleatória , Reprodutibilidade dos Testes , Infecções por Helicobacter/microbiologia , Resultado do Tratamento , Claritromicina/farmacologia , Modelos Animais de Doenças , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Gastrite/microbiologia , Camundongos Endogâmicos C57BL , Antibacterianos/farmacologia
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