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1.
Food Chem ; 451: 139447, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38688097

RESUMO

An eco-friendly hydrothermal method synthesized VS2 nanosheets. Several spectroscopic and microscopic approaches (TEM) were used to characterize the produced VS2 nanosheet microstructure. VS2, Chitosan, and nanocomposite were used to immobilize watermelon (Citrullus lanatus) urease. Optimization using the Response Surface Methodology and the Box-Behnken design yielded immobilization efficiencies of 65.23 %, 72.52 %, and 87.68 % for chitosan, VS2, and nanocomposite, respectively. The analysis of variance confirmed the mathematical model's validity, enabling additional research. AFM, SEM, FTIR, Fluorescence microscopy, and Cary Eclipse Fluorescence Spectrometer showed urease conjugation to the matrix. During and after immobilization, FTIR spectra showed a dynamic connectivity of chemical processes and bonding. The nanocomposite outperformed VS2 and chitosan in pH and temperature. Chitosan and VS2-immobilized urease were more thermally stable than soluble urease, but the nanocomposite-urease system was even more resilient. The nanocomposite retained 60 % of its residual activity after three months of storage. It retains 91.8 % of its initial activity after 12 reuse cycles. Nanocomposite-immobilized urease measured milk urea at 23.62 mg/dl. This result was compared favorably to the gold standard p-dimethylaminobenzaldehyde spectrophotometric result of 20 mg/dl. The linear range is 5 to 70 mg/dl, with a LOD of 1.07 (±0.05) mg/dl and SD of less than 5 %. The nanocomposite's ksel coefficient for interferents was exceptionally low (ksel < 0.07), indicating urea detection sensitivity. Watermelon urease is suitable for dairy sector applications due to its availability, immobilization on nanocomposite, and reuse.


Assuntos
Quitosana , Citrullus , Enzimas Imobilizadas , Leite , Nanocompostos , Urease , Citrullus/química , Citrullus/enzimologia , Urease/química , Urease/metabolismo , Quitosana/química , Enzimas Imobilizadas/química , Nanocompostos/química , Leite/química , Animais , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Ureia/química
2.
Infect Disord Drug Targets ; 24(2): e021123223053, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38291868

RESUMO

Infections caused by fungi can be mildly bothersome or fatal, causing life-threatening conditions or even death. Antifungal drugs have used synthetic chemicals, organic compounds, and phytoconstituents in their formulations to treat fungal infections. Research into novel antifungal drugs has progressed more rapidly than into antibacterial treatments. This can be attributed to the low resistance of fungal infections to antifungal bioactivities and the relatively low incidence of these diseases. Carrier systems based on nanotechnology have generated much interest recently because of the incredible potential of these systems. By using nanoarchitecture as a better carrier and drug delivery system (DDS), we can have greater antifungal effectiveness, bioavailability, targeted action, and less cytotoxicity, a development made possible using nanotechnology. This review discusses various nanocarrier-based technologies in addition to other nanotechnological methods. These include liposomes, transfersomes, ethosomes, niosomes, dendrimers, polymeric nanoparticles, polymer nanocomposites, metallic nanoparticles, carbon nanomaterials, etc. This review focused on general information regarding fungi infections, different antifungal agent types and mechanisms of action, and an overview of formulation strategies such as nanotechnology systems, which are frequently researched for antifungal therapies. We concluded that new drug delivery systems are crucial to delivering antifungal medicines to their target site with the optimum concentration. The researchers also concentrated on these innovative drug delivery systems, which primarily focus on regulating and maintaining the release of antifungal drugs.


Assuntos
Nanopartículas Metálicas , Micoses , Humanos , Antifúngicos/uso terapêutico , Antifúngicos/química , Sistemas de Liberação de Medicamentos , Lipossomos/química , Nanotecnologia
3.
Assay Drug Dev Technol ; 19(2): 63-74, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33090876

RESUMO

In this present study, floating microspheres of repaglinide were successfully fabricated by the solvent evaporation technique with varying ratios of guar gum, hydroxypropyl methylcellulose, and ethylcellulose with polyvinyl alcohol. Microspheres were characterized by production yield, particle size, in vitro buoyancy, entrapment efficiency, in vitro drug release, and in vivo floating behavior in albino rats. The formulation process was optimized for stirring speed (X1) and concentration of polymer ratio (X2) on dependent variables such as percentage entrapment efficiency, percentage yield, in vitro buoyancy, and percentage of drug release by the 32 factorial Design-Expert® 12, trial version, software. The optimized formulation was characterized by Fourier transform infrared spectroscopy, powder X-ray diffraction, differential scanning calorimetry, and scanning electron microscopy and was successfully formulated with the highest percentage of cumulative drug release (94.26 ± 3.10), entrapment efficiency (74.70% ± 2.16%), and particle size (50.34 ± 3.67 µm) and remains buoyant for 24 h in simulated gastric fluid (0.1N HCL) with high in vitro buoyancy percent (84.90 ± 2.88). When the drug-polymer solution of dichloromethane and ethanol is dropped in polyvinyl alcohol solution, it leads to the formation of a shell and produces cavities, creating the buoyant nature of floating microspheres. X-ray imaging indicates the uniform distribution and buoyant nature of microspheres in the gastric fluid for a 10-h period.


Assuntos
Carbamatos/química , Galactanos/química , Mananas/química , Microesferas , Piperidinas/química , Gomas Vegetais/química , Animais , Liberação Controlada de Fármacos , Tamanho da Partícula , Ratos , Propriedades de Superfície
4.
Asian Pac J Cancer Prev ; 15(11): 4405-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24969860

RESUMO

Reactive oxygen species (ROS), highly reactive molecules, are produced by living organisms as a result of normal cellular metabolism and environmental factors, and can damage nucleic acids and proteins, thereby altering their functions. The human body has several mechanisms to counteract oxidative stress by producing antioxidants. A shift in the balance between oxidants and antioxidants in favor of oxidants is termed as "oxidative stress". Paradoxically, there is a large body of research demonstrating the general effect of oxidative stress on signaling pathways, less is known about the initial and direct regulation of signaling molecules by ROS, or what we term the "oxidative interface." This review focuses on the molecular mechanisms through which ROS directly interact with critical signaling molecules to initiate signaling in a broad variety of cellular processes, such as proliferation and survival (MAP kinases and PI3 kinase), ROS homeostasis, and antioxidant gene regulation (Ref-1 and Nrf-2). This review also deals with classification as well as mechanisms of formation of free radicals, examining their beneficial and deleterious effects on cellular activities and focusing on the potential role of antioxidants in preventing and repairing damage caused by oxidative stress. A discussion of the role of phytochemical antioxidants in oxidative stress, disease and the epigenome is included.


Assuntos
Antioxidantes/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Estresse Oxidativo/genética , Animais , Proliferação de Células/genética , Sobrevivência Celular/genética , Radicais Livres/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética
5.
Asian Pac J Cancer Prev ; 14(8): 4495-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24083691

RESUMO

Morinda citrifolia, also known as Great Morinda, Indian Mulberry, or Noni, is a plant belonging to the family Rubiaceae. A number of major chemical compounds have been identified in the leaves, roots, and fruits of Noni plant. The fruit juice is in high demand in alternative medicine for different kinds for illnesses such as arthritis, diabetes, high blood pressure, muscle ached and pains, menstrual difficulties, headache, heart diseases, AIDS, gastric ulcer, sprains, mental depression, senility, poor digestion, arteriosclerosis, blood vessel problems, and drug addiction. Several studies have also demonstrated the anti-inflammatory, antioxidant and apoptosis-inducing effect of Noni in various cancers. Based on a toxicological assessment, Noni juice was considered as safe. Though a large number of in vitro, and, to a certain extent, in vivo studies demonstrated a range of potentially beneficial effects, clinical data are essentially lacking. To what extent the findings from experimental pharmacological studies are of potential clinical relevance is not clear at present and this question needs to be explored in detail before an recommendations can be made.


Assuntos
Competência Clínica/normas , Conhecimento , Morinda/química , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Estudos de Avaliação como Assunto , Humanos
6.
Asian Pac J Cancer Prev ; 13(12): 6295-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23464448

RESUMO

Oxidant/antioxidant balance has been suggested as an important factor for initiation and progression of cancer. The objective of this study was to determine changes in the levels of malondialdehyde (MDA), nitric oxide (NO), total cholesterol, triglycerides, LDL-cholesterol, HDL-cholesterol, total antioxidant capacity (TAC), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) activities in serum samples of breast cancer patients (n=30) and healthy subjects (n=100). MDA and NO levels were found to be increased in breast cancer patients compared to the healthy subject group (p<0.05). Total cholesterol and triglycerides were elevated; and HDL- cholesterol level was found to be decreased in the cancer patients as compared to the healthy subjects (p<0.05). Compared to the healthy group, both serum TAC levels (p<0.001) and activity of SOD and GSH-Px (p=0.05) were found to be decreased in the breast cancer patients as compared to the healthy controls. Considering the data presented in this study, we suggest that free radicals induce lipid eroxidation and peroxidation of unsaturated fatty acid with decreased activity of enzymatic antioxidants in breast cancer.


Assuntos
Antioxidantes/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/fisiopatologia , Lipídeos/fisiologia , Estresse Oxidativo/fisiologia , Estudos de Casos e Controles , Colesterol/metabolismo , Feminino , Glutationa Peroxidase/metabolismo , Humanos , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Superóxido Dismutase/metabolismo , Triglicerídeos/metabolismo
7.
Int J Pharm ; 371(1-2): 47-55, 2009 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-19135515

RESUMO

A voltammetric sensor based on a molecularly imprinted polymer (MIP) brush grafted to sol-gel film on graphite electrode is reported for the selective and sensitive analysis of barbituric acid (BA) in aqueous, blood plasma, and urine samples. The modified electrode was preanodised at +1.6 V (vs. saturated calomel electrode), where encapsulated BA involved hydrophobically induced hydrogen bondings, in MIP cavities exposed at the film/solution interface, at pH 7.0. Scanning electron microscopy (SEM) was employed to characterise the surface morphology of the resultant imprinted film of MIP brush. The differential pulse, cathodic stripping voltammetry (DPCSV) technique was employed to investigate the binding performance of the sol-gel-modified imprinted polymer brush, which yielded a linear response in the range of 4.95-100.00 microg mL(-1) of BA with a detection limit of 1.6 microg mL(-1) (S/N=3).


Assuntos
Barbitúricos/análise , Grafite/química , Impressão Molecular/métodos , Polímeros/química , Barbitúricos/sangue , Barbitúricos/urina , Eletroquímica , Eletrodos , Humanos , Ligação de Hidrogênio , Microscopia Eletrônica de Varredura , Estrutura Molecular , Transição de Fase , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
8.
Biomed Chromatogr ; 23(5): 499-509, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19101922

RESUMO

Main inborn errors of metabolism diagnosable through uracil (Ura) analysis and the therapeutic monitoring of toxic 5-fluorouracil (5FU) in dihydro pyrimidine dehydrogenase (DPD) deficient patients require a sensitive, reproducible, selective and accurate method. In this work, an artificial receptor in the format of molecularly imprinted polymer (MIP) brush 'grafted to' the surface of sol-gel immobilized on cost-effective homemade solid-phase microextraction (SPME) fibers, individually imprinted with either of Ura and 5FU, was used in combination with a voltammetric sensor duly modified with the same MIP. This combination provided up to 10- and 8.4-fold preconcentrations of Ura and 5FU, respectively, which was more than sufficient for achieving stringent detection limits in the primitive diagnosis of uracil disorders and fluoropyrimidine toxicity in DPD-deficient patients. The proposed method permits the assessment of Ura and 5FU plasma concentrations with detection limits pf 0.0245 and 0.0484 ng mL(-1) (RSD = 1.0-2.5%, S/N = 3), respectively, without any problems of non-specific false-positives and cross-reactivities in complicated matrices of biological samples.


Assuntos
Fluoruracila/análise , Impressão Molecular/métodos , Microextração em Fase Sólida/métodos , Uracila/análise , Benzenossulfonatos/química , Sítios de Ligação , Deficiência da Di-Hidropirimidina Desidrogenase/diagnóstico , Fluoruracila/sangue , Fluoruracila/isolamento & purificação , Humanos , Microscopia Eletrônica de Varredura , Impressão Molecular/economia , Impressão Molecular/instrumentação , Polímeros/química , Sensibilidade e Especificidade , Microextração em Fase Sólida/economia , Microextração em Fase Sólida/instrumentação , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Uracila/sangue , Uracila/isolamento & purificação
9.
J Chromatogr A ; 1198-1199: 59-66, 2008 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-18539289

RESUMO

Clinical manifestations owing to ascorbic acid deficiency demand an easy-to-use, rapid, robust and inexpensive technique, which can measure serum ascorbic acid at ultratrace level to attend the problem of hypovitaminosis C and acute cases of scurvy. In the present work, a novel molecularly imprinted polymer (MIP)-coated solid-phase microextraction (SPME) fiber that could be coupled to a complementary MIP-sensor was prepared with ascorbic acid as a template molecule. The characteristics and applications of this fiber were investigated. The same MIP receptor for both SPME and the corresponding sensor was able to enhance the preconcentration of analyte substantially so as to attain the stringent level of sensitivity in highly diluted aqueous, blood serum and pharmaceutical samples. The extraction yield of ascorbic acid (AA) with the MIP-coated fiber was found to be quantitative (detection limit 0.0396 ng mL(-1), RSD=2.3%, S/N=3) in aqueous samples without any problem of non-specific false positive results and cross-reactivity.


Assuntos
Ácido Ascórbico/análise , Polímeros/química , Microextração em Fase Sólida/métodos , Ácido Ascórbico/sangue , Ácido Ascórbico/química , Humanos , Microscopia Eletrônica de Varredura , Impressão Molecular , Estrutura Molecular , Reprodutibilidade dos Testes
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