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1.
Artif Cells Nanomed Biotechnol ; 52(1): 35-45, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38112317

RESUMO

Fabrication of haemostatic materials with excellent antimicrobial, biocompatible and biodegradable properties remains as a major challenge in the field of medicine. Haemostatic agents play vital role in protecting patients and military individuals during emergency situations. Natural polymers serve as promising materials for fabricating haemostatic compounds due to their efficacy in promoting hemostasis and wound healing. In the present work, sodium alginate/aloe vera/sericin (SA/AV/S) scaffold has been fabricated using a simple cost-effective casting method. The prepared SA/AV/S scaffolds were characterised for their physicochemical properties such as scanning electron microscope, UV-visible spectroscopy and Fourier transform infra-red spectroscopy. SA/AV/S scaffold showed good mechanical strength, swelling behaviour and antibacterial activity. In vitro experiments using erythrocytes proved the hemocompatible and biocompatible features of SA/AV/S scaffold. In vitro blood clotting assay performed using human blood demonstrated the haemostatic and blood absorption properties of SA/AV/S scaffold. Scratch wound assay was performed to study the wound healing efficacy of prepared scaffolds. Chick embryo chorioallantoic membrane assay carried out using fertilised embryos proved the angiogenic property of SA/AV/S scaffold. Thus, SA/AV/S scaffold could serve as a potential haemostatic healthcare product due to its outstanding haemostatic, antimicrobial, hemocompatible, biocompatible and angiogenic properties.


Assuntos
Aloe , Hemostáticos , Sericinas , Embrião de Galinha , Animais , Humanos , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Alginatos/farmacologia , Alginatos/química , Aloe/química , Hemostáticos/farmacologia , Alicerces Teciduais/química , Antibacterianos/farmacologia , Antibacterianos/química , Hemostasia
2.
Appl Biochem Biotechnol ; 195(11): 6607-6632, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36892681

RESUMO

Orthopedic infections due to biofilm formation in biomaterial-based implants have become challenging in bone tissue engineering. In the present study, in vitro antibacterial analysis of amino-functionalized MCM-48 mesoporous silica nanoparticles (AF-MSNs) loaded with vancomycin is analyzed for its potential as a drug carrier for the sustained/controlled release of vancomycin against Staphylococcus aureus. The effective incorporation of vancomycin into the inner core of AF-MSNs was observed by alternation in the absorption frequencies obtained by Fourier transform infrared spectroscopy (FTIR). Dynamic light scattering (DLS) and high resolution-transmission electron microscopy (HR-TEM) results show that all the AF-MSNs had homogeneous spherical shapes with a mean diameter of 165.2 ± 1.25 nm, and there is a slight change in the hydrodynamic diameter after vancomycin loading. Furthermore, the zeta potential of all the AF-MSNs (+ 30.5 ± 0.54 mV) and AF-MSN/VA (+ 33.3 ± 0.56 mV) were positively charged due to effective functionalization with 3-aminopropyl triethoxysilane (APTES). Furthermore, cytotoxicity results show that the AF-MSNs have better biocompatibility than non-functionalized MSNs (p < 0.05), and results prove AF-MSNs loaded with vancomycin show better antibacterial effect against S. aureus than non-functionalized MSNs. Results confirm that bacterial membrane integrity was affected by treatment with AF-MSNs and AF-MSN/VA by staining the treated cells with FDA/PI. Field emission scanning electron microscopy (FESEM) analysis confirmed the shrinkage of bacterial cells and membrane disintegration. Furthermore, these results demonstrate that amino-functionalized MSNs loaded with vancomycin significantly increased the anti-biofilm and biofilm inhibitory effect and can be incorporated with biomaterial-based bone substitutes and bone cement to prevent orthopedic infections post-implantation.


Assuntos
Infecções Bacterianas , Substitutos Ósseos , Nanopartículas , Humanos , Vancomicina/farmacologia , Portadores de Fármacos/química , Dióxido de Silício/química , Staphylococcus aureus , Nanopartículas/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Porosidade
3.
Appl Biochem Biotechnol ; 195(7): 4617-4636, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36652090

RESUMO

Bone regeneration or restoration is a series of well-ordered physiological activities that occur throughout a person's life, they are continuously being repaired and remodeled. A conventional bone repair procedure, such as autograft and allograft bone transplant, has failed to address bone reconstruction disputes and complexity. On the other hand, Tissue Engineering is a potential therapy option for repairing rather than replacing the damaged tissue. Biomaterials in bone tissue engineering (BTE) help pave the way for damaged tissues as an artificial extracellular matrix, facilitating new tissue growth. Collagen-based biomaterials for repair and replacement have inspired much interest in the hunt for versatile biomaterials compatible with human tissue. It is a major organic component of extracellular matrix in bone and has been employed as scaffolding material in BTE for decades. In this review, we documented the role of collagen in BTE, focusing on collagen type I, its crosslinking capability, collagen-based biomaterials, and fabrication methods. It also considers osteoblast citration a critical process in bone formation, a unique perspective for an old relationship.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Humanos , Engenharia Tecidual/métodos , Materiais Biocompatíveis , Osso e Ossos , Colágeno
4.
J Biomed Mater Res B Appl Biomater ; 111(5): 1074-1088, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36583262

RESUMO

A non-healing wound is a common problem associated with diabetes mellitus. Chronic inflammation, challenging re-epithelization, unusual growth factors, and impaired angiogenesis are the multifactorial events that contribute to impaired wounds. Hence, in the present work, an innovative GA-CSNPs nanocomposite scaffold has been fabricated by integrating Gallic acid (GA) loaded chitosan nanoparticles (GA-CSNPs) into a genipin crosslinked collagen-fibrin (Col-fibrin) scaffold as wound dressing material. The in vitro RT-PCR study carried out using NIH/3T3 mouse fibroblast cells showed that treatment with GA-CSNPs nanocomposite scaffold aids in an upsurge in the expression of Col-I, III, and VEGF, which further supports the synthesis of extracellular matrix, increases neovascularization and development of the established vascular system. In vivo wound contraction study results revealed that diabetic wounds treated with GA-CSNPs nanocomposite scaffold show a faster rate of wound closure (p < .001), histopathology results showed accelerated fibroblast cell migration, reduction of the inflammatory cells, enhanced collagen along with hexosamine synthesis. In addition, immunohistochemistry results showed increased vascularization, a significant decrease in macrophage recruitment, and reduced expression of MMP-9 compared to the Col-fibrin scaffold and Control groups. Overall data suggest that the fabricated GA-CSNPs nanocomposite porous 3-D scaffold can be a hopeful therapeutic choice for diabetic wound management.


Assuntos
Diabetes Mellitus , Nanocompostos , Camundongos , Animais , Ácido Gálico/farmacologia , Fibrina/farmacologia , Cicatrização , Colágeno/farmacologia
5.
ACS Appl Bio Mater ; 5(6): 2956-2964, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35620928

RESUMO

The advent of bio-nanotechnology has revolutionized nanodrug delivery by improving drug efficacy and safety. Nevertheless, acceptable carriers for therapeutic molecules are one of the most difficult challenges in drug delivery. Graphene material-based (GMB) and polymer-based drug-loaded nanocarriers have both demonstrated clinical advantages in delivering drugs of interest in vitro/in vivo. Cisplatin (CDDP) is an inorganic chemotherapeutic drug that is commonly used to treat a variety of cancers. However, its clinical use is associated with drug resistance and few side effects, which reduces its antitumor effects. Therefore, we developed a CDDP-loaded chitosan-functionalized graphene oxide nanocomposite (CDDP@CS-GO NC)-based nanodrug delivery system (NDDS). Flow cytometry and confocal imaging show that the CDDP@CS-GO NCs lead to significantly increased intracellular drug accumulation in tumor cells. Cancer cells take up the nanocomposite via endocytosis and can generate intracellular reactive oxygen species (ROS) to increase mitochondrial membrane potential loss (Δψm) and enable cytochrome-c release, followed by the dysregulation of Bcl-2 into the cytosol and activation of caspase-3 to induce cancer cell apoptosis. In vitro experiments demonstrated the excellent cancer therapeutic effect with few side effects of the carriers. CDDP@CS-GO NCs are expected to play an important role in responsive NDDSs for cancer therapy.


Assuntos
Grafite , Nanocompostos , Neoplasias do Colo do Útero , Cisplatino/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Feminino , Humanos , Neoplasias do Colo do Útero/tratamento farmacológico
6.
Comput Biol Med ; 146: 105419, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35483225

RESUMO

Data science has been an invaluable part of the COVID-19 pandemic response with multiple applications, ranging from tracking viral evolution to understanding the vaccine effectiveness. Asymptomatic breakthrough infections have been a major problem in assessing vaccine effectiveness in populations globally. Serological discrimination of vaccine response from infection has so far been limited to Spike protein vaccines since whole virion vaccines generate antibodies against all the viral proteins. Here, we show how a statistical and machine learning (ML) based approach can be used to discriminate between SARS-CoV-2 infection and immune response to an inactivated whole virion vaccine (BBV152, Covaxin). For this, we assessed serial data on antibodies against Spike and Nucleocapsid antigens, along with age, sex, number of doses taken, and days since last dose, for 1823 Covaxin recipients. An ensemble ML model, incorporating a consensus clustering approach alongside the support vector machine model, was built on 1063 samples where reliable qualifying data existed, and then applied to the entire dataset. Of 1448 self-reported negative subjects, our ensemble ML model classified 724 to be infected. For method validation, we determined the relative ability of a random subset of samples to neutralize Delta versus wild-type strain using a surrogate neutralization assay. We worked on the premise that antibodies generated by a whole virion vaccine would neutralize wild type more efficiently than delta strain. In 100 of 156 samples, where ML prediction differed from self-reported uninfected status, neutralization against Delta strain was more effective, indicating infection. We found 71.8% subjects predicted to be infected during the surge, which is concordant with the percentage of sequences classified as Delta (75.6%-80.2%) over the same period. Our approach will help in real-world vaccine effectiveness assessments where whole virion vaccines are commonly used.


Assuntos
COVID-19 , Vacinas Virais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/uso terapêutico , Humanos , Aprendizado de Máquina , Pandemias , SARS-CoV-2 , Vacinas de Produtos Inativados , Vírion
7.
Appl Biochem Biotechnol ; 194(1): 464-478, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34611854

RESUMO

Nanoparticle research is fascinating and getting hold of consequences due to the wide variety of applications in the biomedical field. Green synthesis of nanoparticles is a cost-effective and eco-friendly approach. It can be synthesised using fungi, algae, plant, yeast, bacteria, microbial enzymes etc. Our current research study focuses on the green synthesis of silver nanoparticles using seed extract of Cassia tora. The colour change from yellow to red colour confirms the formation of silver nanoparticles. The synthesised silver nanoparticles were characterised by Ultraviolet-Visible spectroscopy, Fourier-transform infrared (FTIR), X-ray diffraction analysis (XRD), Scanning Electron Microscopy (SEM) and antibacterial efficacy against three different strains were analysed. The surface plasmon resonance of synthesised AgNPs using Cassia tora seed extract shows maximum absorption peak at 423 nm in UV-visible spectroscopy. X-ray diffraction displays the crystalline nature of synthesised AgNPs and they exhibited four distinct peaks at 36.69°, 42.92°, 63.27° and 76.46°. The particle size of synthesised AgNPs observed through SEM was found to be 55.80 nm, 58.97 nm, 61.06 nm, 63.26 nm and 64.80 nm. S.aureus exhibited maximum zone of inhibition of 12 mm and 13 mm when treated with 25 and 50 µl of the synthesised nanoparticles. Thus, the green synthesised silver nanoparticle using Cassia tora seed extract proved to possess strong anti-bacterial activity.


Assuntos
Antibacterianos , Cassia/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Sementes/química , Prata , Staphylococcus aureus/crescimento & desenvolvimento , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Química Verde , Prata/química , Prata/farmacologia
8.
Appl Biochem Biotechnol ; 194(1): 302-322, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34762271

RESUMO

The most important role of tissue engineering is to develop a biomaterial with a property that mimics the extracellular matrix (ECM) by enhancing the lineage-specific proliferation and differentiation with favorable regeneration property to aid in new tissue formation. Thus, to develop an ideal scaffold for bone repair, we have fabricated a composite nanofiber by the coaxial electrospinning technique. The coaxial electrospun nanofiber contains the core layer, consisting of polyvinyl alcohol (PVA) blended with oregano extract and mesoporous silica nanoparticles (PVA-OE-MSNPs), and the shell layer, consisting of poly-ε-caprolactone blended with collagen and hydroxyapatite (PCL-collagen-HAP). We evaluated the physicochemical properties of the nanofibers using X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). In vitro biocompatibility, cell adhesion, cell viability, and osteogenic potential were evaluated by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenlytetrazolium bromide (MTT), calcein AM, and alkaline phosphatase (ALP) activity and Alizarin Red staining in NIH 3T3/MG-63 cells. The results showed that the nanoparticle-incorporated coaxial nanofiber was observed with bead-free, continuous, and uniform fiber morphology with a mean diameter in the range of 310 ± 125 nm. From the biochemical studies, it is observed that the incorporation of nanofiber with HAP and MSNPs shows good swelling property with ideal porosity, biodegradation, and enhanced biomineralization property. In vitro results showed that the scaffolds with nanoparticles have higher cell adhesion, cell viability, ALP activity, and mineralization potential. Thus, the fabricated nanofiber could be an appropriate implantable biomaterial for bone tissue engineering.


Assuntos
Materiais Revestidos Biocompatíveis , Teste de Materiais , Nanofibras , Osteogênese/efeitos dos fármacos , Dióxido de Silício , Animais , Linhagem Celular , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Avaliação de Medicamentos , Camundongos , Nanofibras/química , Nanofibras/uso terapêutico , Porosidade , Dióxido de Silício/química , Dióxido de Silício/farmacologia
9.
Mater Sci Eng C Mater Biol Appl ; 126: 112149, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34082960

RESUMO

Hydroxyapatite (HAP) nanopowders with different manganese (Mn) and selenium (Se) contents with Mn/Ca and Se/P molar ratio of 1 mol%, 2.5 mol% and 5 mol% were synthesized by wet-co-chemical precipitation method. The results revealed that with either Mn or Se doping, ion-substituted apatite phase was achieved with good crystallographic features. The combined evidence obtained from spectrometric techniques revealed that nanocrystalline HAP was effectively doped with Mn and Se ions, where Se in form of SeO32- replaced PO43- and Mn2+ replaced Ca2+. Mn and Se doped HAP samples exhibited rod-like and needle-like morphology with strong tendency to form agglomerates. HAP enriched with Mn and Se represented a strong antibacterial effect and also showed prominent blood compatibility. From the biocompatibility testing, it was evident that Mn and Se doped HAP augmented the osteoblasts adhesion, migration and proliferation in a dose-dependent manner. To conclude from this study, it is clearly evident that the doping amount of both Mn and Se ions can determine the size and morphology of the final HAP product. Therefore, Mn and Se HAP nanopowders with molar ratio less than 5 mol% without any heat treatment can provide good crystallographic features to HAP with satisfying micro-structural, thermal and biological properties.


Assuntos
Durapatita , Selênio , Regeneração Óssea , Íons , Manganês
10.
Colloids Surf B Biointerfaces ; 206: 111922, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34157519

RESUMO

The present study explores the therapeutic efficacy of sodium alginate-chitosan scaffolds loaded with Chrysin (ALG-CS-CHY) for dermal wound management. Scaffolds were prepared by the vacuum freeze-drying method. The physiochemical characterization was done through Fourier Transform Infra-Red Spectroscopy (FTIR), which revealed the interactions between the scaffold's functional groups and the drug. Surface Electron microscopy (SEM) showed a porous architecture varying from 200-400 µm. X-ray Diffraction (XRD) showed an ionic interaction between ALG-CS leading to their excellent compatibility. Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) results suggest increased ALG-CS scaffold's thermal stability. In-vitro biodegradation behavior demonstrated controlled degradation with lysozyme. The swelling ratio was highest in the first hour and decreased slowly with time, and the porosity analysis showed a high degree of porosity. The ALG-CS scaffold showed sustained drug availability and minimized re-application, which contributes to effective healing and treatment. The blood compatibility and whole blood clotting ability of the scaffold significantly improved after incorporating the drug. Calcein AM, Propidium iodide, was used for live and dead cell staining, which confirmed that fabricated ALG-CS-CHY scaffolds are biocompatible and facilitate cell growth and cell proliferation. In-vivo and in-vitro observations show that the experimental group treated using the ALG-CS-CHY reduces the period of re-epithelization, accelerated fibroblast cell migration, and contracted wound significantly (p < 0.001) compared to other groups. ALG-CS-CHY scaffolds also increased collagen deposition, hexosamine synthesis, accelerates angiogenesis, and recruiting immune cells at the site of a wound. These results suggest ALG-CS-CHY scaffold serves as an effective dressing for dermal wound management.


Assuntos
Quitosana , Alginatos , Flavonoides , Polifenóis , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Alicerces Teciduais , Cicatrização
11.
Elife ; 102021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33876727

RESUMO

To understand the spread of SARS-CoV2, in August and September 2020, the Council of Scientific and Industrial Research (India) conducted a serosurvey across its constituent laboratories and centers across India. Of 10,427 volunteers, 1058 (10.14%) tested positive for SARS-CoV2 anti-nucleocapsid (anti-NC) antibodies, 95% of which had surrogate neutralization activity. Three-fourth of these recalled no symptoms. Repeat serology tests at 3 (n = 607) and 6 (n = 175) months showed stable anti-NC antibodies but declining neutralization activity. Local seropositivity was higher in densely populated cities and was inversely correlated with a 30-day change in regional test positivity rates (TPRs). Regional seropositivity above 10% was associated with declining TPR. Personal factors associated with higher odds of seropositivity were high-exposure work (odds ratio, 95% confidence interval, p value: 2.23, 1.92-2.59, <0.0001), use of public transport (1.79, 1.43-2.24, <0.0001), not smoking (1.52, 1.16-1.99, 0.0257), non-vegetarian diet (1.67, 1.41-1.99, <0.0001), and B blood group (1.36, 1.15-1.61, 0.001).


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Teste Sorológico para COVID-19 , COVID-19/epidemiologia , SARS-CoV-2/imunologia , Biomarcadores/sangue , COVID-19/diagnóstico , COVID-19/imunologia , COVID-19/virologia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Imunidade Humoral , Índia/epidemiologia , Estudos Longitudinais , Masculino , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Estudos Soroepidemiológicos , Fatores de Tempo
12.
Int J Biol Macromol ; 165(Pt A): 930-947, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33011266

RESUMO

The present study explores the curative efficacy of collagen-fibrin scaffold with Gallic acid loaded Chitosan nanoparticles (GA-CSNPs) in wound healing. GA-CSNPs were synthesized by ionotropic gelation and the incorporation of GA was confirmed with Fourier Transform Infra-Red Spectroscopy (FTIR). Change in the crystal structure of GA was confirmed by X-ray Powder Diffraction (X-PRD) and Differential Scanning Colorimetry (DSC). Surface Electron microscopy (SEM) showed that GA-CSNPs have roughly spherical morphology and mean diameter of 251.3 nm with positive zeta potential. The drug encapsulation was found to be 34.2-73.5%. Col-fibrin scaffolds crosslinked with genipin using cryodesiccation technique showed a sheet-like architecture with 66.78% of crosslinking degree. Scaffolds exhibited porosity of 38.49% and decrease in swelling ratio. Biodegradation study demonstrated controlled degradation with collagenase and Thermogravimetric analysis (TGA) showed excellent thermal stability and sustained drug release property. In vitro and in vivo study results indicate that the group treated with nanocomposite scaffold exhibits enhanced re-epithelialization, accelerated fibroblast cell migration, wound healing and significant wound contraction (p < 0.001) compared to control. Nanocomposite scaffolds also accelerates angiogenesis, hexosamine synthesis, collagen deposition and recruiting immune cells at wound area. These results suggest nanocomposite scaffold values for their use as a promising wound dressing material for better tissue regeneration.


Assuntos
Quitosana/química , Ácido Gálico/farmacologia , Nanopartículas/química , Alicerces Teciduais/química , Bandagens , Quitosana/farmacologia , Colágeno/química , Colágeno/farmacologia , Fibrina/química , Fibrina/farmacologia , Ácido Gálico/química , Humanos , Microscopia Eletrônica , Polímeros/química , Polímeros/farmacologia , Regeneração/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
13.
J Biochem Mol Toxicol ; 34(12): e22587, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32726518

RESUMO

Colorectal cancer is one of the most leading death-causing cancers in the world. Vernodalin, a cytotoxic sesquiterpene, has been reported to possess anticancer properties against human breast cancer cells. We aimed to examine the anticancer mechanism of vernodalin on human colon cancer cells. Vernodalin was used on human colon cancer cells, HT-29 and HCT116. The cytotoxicity of vernodalin on human colon cancer cells was determined through in vitro 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide assay. Small interfering RNA was used to analyze the cascade activation of mitogen-activated protein kinase (MAPK) pathway, c-Jun N-terminal kinase (JNK) in HT-29, and HCT116 cells against vernodalin treatment. The protein expressions of caspase 3, Bcl-2, and Bax were examined through Western blot analysis. Immunoblot analysis on the JNK, ERK, and p38 MAPK pathways showed increased activation due to vernodalin treatment. It was proven from the JNK and p38 inhibition test that both pathways are significantly activated by vernodalin to induce apoptosis. Our results, collectively, showed the apoptosis-induced anticancer mechanism of vernodalin on human colon cancer cells that was mediated through the activation of JNK pathway and apoptotic regulator proteins. These results suggest that vernodalin could be developed as a potent chemotherapeutic agent for human colorectal cancer treatment.


Assuntos
Apoptose/efeitos dos fármacos , MAP Quinase Quinase 4/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ativação Enzimática , Células HCT116 , Células HT29 , Humanos , Estresse Oxidativo/efeitos dos fármacos , Sesquiterpenos/farmacologia
14.
Nanomedicine ; 29: 102251, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32592758

RESUMO

Conventional bone repair therapies like the autologous and allogenic bone grafts have failed to meet challenges in bone reconstruction along with complications. Tissue engineering (TE) has emerged as a developing treatment regimen in regenerating damaged tissues rather than replacing them. In TE, biomaterials act as template for damaged tissues and function as artificial extracellular matrix (ECM), facilitating new tissue formation. Since single type biomaterial has unsuccessful regeneration properties, focus on using composites of natural and synthetic biomaterials is encouraged. In the current study, we have evaluated the potential of a graphene-based nano-composite scaffold as a biomaterial to enhance bone tissue regeneration. The findings demonstrate that the scaffold with Graphene oxide (GO) exhibits enhanced levels of biocompatibility, alkaline phosphatase activity, and calcium deposits, thereby emphasizing the hypothesis that fabricated nanocomposite scaffolds are promising osteoinductive products for bone repair/regeneration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Fibrina/farmacologia , Nanocompostos/química , Osteogênese/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Fibrina/química , Grafite/química , Grafite/farmacologia , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Osteogênese/genética , Ratos , Engenharia Tecidual , Alicerces Teciduais
15.
Oxid Med Cell Longev ; 2017: 5213186, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29098061

RESUMO

A number of xenobiotic-inducible cytochrome P450s (CYPs) are now known to be localized in the mitochondrial compartment, though their pharmacological or toxicological roles remain unclear. Here, we show that BNF treatment markedly inhibits liver mitochondrial O2 consumption rate (OCR), ADP-dependent OCR, and also reserve OCR, in wild-type mice but not in Cyp1a1/1a2(-/-) double knockout mice. BNF treatment markedly affected mitochondrial complex I and complex IV activities and also attenuated mitochondrial gene expression. Furthermore, under in vitro conditions, BNF treatment induced cellular ROS production, which was inhibited by mitochondria-targeted antioxidant Mito-CP and CYP inhibitor proadefin, suggesting that most of the ROS production was intramitochondrial and probably involved the catalytic activity of mitochondrial CYP1 enzymes. Interestingly, our results also show that the AHR antagonist resveratrol, markedly attenuated BNF-induced liver mitochondrial defects in wild-type mice, confirming the role of AHR and AHR-regulated CYP1 genes in eliciting mitochondrial dysfunction. These results are consistent with reduced BNF-induced mitochondrial toxicity in Cyp1a1/1a2(-/-) mice and elevated ROS production in COS cells stably expressing CYP1A1. We propose that increased mitochondrial ROS production and respiratory dysfunction are part of xenobiotic toxicity. Resveratrol, a chemopreventive agent, renders protection against BNF-induced toxicity.


Assuntos
Citocromo P-450 CYP1A1/genética , Mitocôndrias/metabolismo , Estilbenos/uso terapêutico , beta-Naftoflavona/metabolismo , Animais , Técnicas de Cultura de Células , Masculino , Camundongos , Camundongos Knockout , Resveratrol , Estilbenos/farmacologia
16.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt A): 2992-3001, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27663233

RESUMO

BACKGROUND: A variety of bioimaging tools assists in the diagnosis and evaluation of rheumatoid arthritis (RA) and other osteoarthritis. However, detection of RA in the early stages by targeting its macrophages with suitable contrast agents will help in arresting the progression of the disease. METHODS: In the present study, we investigated the effectiveness of using magnetic fibrin nanoparticles (MFNPs) conjugated with folic acid (FA-MFNPs) as a specific contrast agent to target the activated macrophages, which overexpress the folate receptors (FR) in the knee joints of rats with antigen-induced arthritis (AIA). RESULTS: FA-MFNPs were spherical with an average size of 18.3±1.6nm. In vitro studies have shown effective internalization of FA-MFNPs into the Raw264.7 macrophage cells. In vivo studies were carried out by injecting FA-MFNPs intravenously into the arthritic rats. The results showed enhanced MR imaging in the synovium of arthritic joints. Prussian blue histological staining confirmed uptake of FA-MFNPs by macrophages in the synovial tissue. CONCLUSION: The animal experiment results indicate that FA-MFNPs can be used as a specific MRI contrast agent in identifying phagocytic active macrophages in the synovial joints. GENERAL SIGNIFICANCE: Blood is the precursor source for synthesising the fibrin-based iron oxide (magnetic) nanoparticles (MFNPs) with diameters between 12 and 15nm. It has excellent superparamagnetic behaviour, biocompatibility, osteogenic potency, hemocompatibility, and biodegradable properties. MFNPs-based nanocomposites might be a promising contrast agent for bioimaging.


Assuntos
Artrite Reumatoide/diagnóstico , Artrite Reumatoide/patologia , Meios de Contraste/química , Fibrina/metabolismo , Macrófagos/metabolismo , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/química , Animais , Endocitose/efeitos dos fármacos , Ácido Fólico/metabolismo , Cabras , Hidrodinâmica , Fígado/efeitos dos fármacos , Fígado/patologia , Macrófagos/efeitos dos fármacos , Nanopartículas de Magnetita/ultraestrutura , Masculino , Camundongos , Pós , Células RAW 264.7 , Ratos Wistar , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Coloração e Rotulagem , Eletricidade Estática , Difração de Raios X
17.
Biofactors ; 42(6): 623-637, 2016 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-27255553

RESUMO

Colon cancer is one of the leading causes of cancer mortality, worldwide. Cancer stem cells are attractive targets for therapeutic interventions since their abnormal growth may trigger tumor initiation, progression, and recurrence. Colon cancer in rats were induced with 1, 2-dimethyl hydrazine (DMH) and treated with genistein, an isoflavone rich in the soy food products, which also possesses various biological activities. Genistein treatment regulates enzymatic and non-enzymatic anti-oxidants in the DMH-induced colonic tissue microenvironment. Alcian blue staining in colonic tissue reveals that mucin secretion was found to be depleted in DMH-induced group of animals. The alterations were normalized in the genistein-treated groups. Also, the mast cell population and collagen deposition were reduced as compared to induced group. Genistein treatment reduces the prognostic marker Argyrophilic nuclear organizer region (AgNOR) and proliferating cell nucleolar antigen (PCNA) in DMH-induced group of rats. DMH administration induces oxidative stress, whereas genistein activates nuclear factor-erythroid 2 related factor 2 (Nrf-2) and its downstream target hemoxygenase-1 (HO-1). Colonic stem cell marker protein CD133, CD44, and ß-catenin expressions were found to be increased in DMH-induced group of animals as compared to control group of rats. Genistein treatment suppressed the expression of these stem cell markers suggesting rapid dysfunctional activation and proliferation of colonic stem cell-induced by DMH. The results of this study indicate that genistein administration in rats restored the colonic niche that was damaged by DMH and inhibits colon cancer progression. © 2016 BioFactors, 42(6):623-637, 2016.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Genisteína/farmacologia , Microambiente Tumoral/efeitos dos fármacos , Antígeno AC133/metabolismo , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/patologia , Animais , Antioxidantes/farmacologia , Carcinogênese/efeitos dos fármacos , Carcinogênese/patologia , Proliferação de Células , Colo/efeitos dos fármacos , Colo/patologia , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/patologia , Dimetilidrazinas , Ensaios de Seleção de Medicamentos Antitumorais , Colágenos Fibrilares/metabolismo , Heme Oxigenase-1/metabolismo , Receptores de Hialuronatos/metabolismo , Masculino , Mucinas/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos Wistar , beta Catenina/metabolismo
18.
Asian Pac J Cancer Prev ; 13(8): 4107-12, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23098525

RESUMO

4-Nitroquinoline 1-oxide (4-NQO) a potent oral carcinogen, widely used for induction of oral carcinogenesis, has been found to induce lipid peroxidation in vivo and in vitro. Green tea contains a high content of polyphenols, which are potent antioxidants. Thus green tea polyphenols (GTP) might be expected play a protective role against 4-NQO induced lipid peroxidation and bone marrow toxicity. In the present study, a dose of 200 mg of GTP/kg b.wt/day was given orally for a week, simultaneously animals received 0.2 ml of 0.5% 4-NQO in propylene glycol (5 mg/ml) injected intramuscularly for three times/week. Oxidants and antioxidants such as malendialdehyde (MDA) and thiols, glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD) and catalase (CAT) were significantly decreased in 4-NQO induced animals except MDA, and these parameters were brought back to near normalcy on treatment with GTP. The results suggest that GTP treatment offers significant protection against 4-NQO induced lipid peroxidation and bone marrow toxicity and might be a promising potential candidate for prevention of mutations leading to cancer.


Assuntos
4-Nitroquinolina-1-Óxido/toxicidade , Medula Óssea/efeitos dos fármacos , Carcinógenos/toxicidade , Dano ao DNA/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Polifenóis/farmacologia , Chá/química , Animais , Medula Óssea/patologia , Catalase/metabolismo , Adutos de DNA/efeitos dos fármacos , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Técnicas Imunoenzimáticas , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
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