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1.
ACS Omega ; 5(28): 17090-17101, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32715194

RESUMO

In this study, near-field electrospinning (NFES) is used to fabricate Ba x Sr1-x TiO3 (BST)/poly(vinylidene fluoride) (PVDF) piezoelectric fiber composites with excellent mechanical properties and chemical properties. BST ceramic powder is blended with PVDF solution uniformly to prepare a solution of appropriate conductance. The parameter for BST/PVDF fiber processing is based on PVDF fibers. Scanning electron microscopy, differential scanning calorimetry, microtensile testing, Fourier transform infrared spectroscopy, and electricity test of the blends of BST/PVDF fibers are incorporated. Mechanical properties of the fibers are then measured by microtensile testing. Effects of distinct ratios of Ba/Sr and the content of Ba0.7Sr0.3TiO3 ceramic powder on BST/PVDF piezoelectric fibers are discussed. Finally, BST/PVDF piezoelectric fiber composites are patterned on a poly(ethylene terephthalate) (PET)-based structure with an interdigital electrode as a BST/PVDF flexible energy harvester to capture ambient energy. The results show that the BST ceramic powder is ∼58-93 nm, and the diameters of piezoelectric fiber composites are ∼6.8-13.7 µm. The tensile strength of piezoelectric fiber composites is ∼74.92 MPa, and the Young's coefficient tensile strength is ∼3.74 GPa. Mechanical properties are 2-3 times higher than those of pure PVDF piezoelectric fibers. The maximum open-circuit voltage and closed-loop current of BST/PVDF fibers reached ∼1025 mV and ∼391 nA, respectively. The electromechanical energy conversion efficiency of the BST/PVDF energy harvester is found to be 1-2 times higher than that of the PVDF energy harvester. It is confirmed and validated that the addition of BST ceramic powder could effectively increase the piezoelectric constant of PVDF piezoelectric fibers.

2.
Front Neurosci ; 14: 305, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425743

RESUMO

Nanotechnology utilizes engineered materials and devices which function with biological systems at the molecular level and could transform the management of neurodegenerative diseases (NDs) by provoking, reacting to, and intermingling with target sites to stimulate physiological responses while minimizing side effects. Blood-brain barrier (BBB) protects the brain from harmful agents, and transporting drugs across the BBB is a major challenge for diagnosis, targeting, and treatment of NDs. The BBB provides severe limitations for diagnosis and treatment of Alzheimer's disease (AD), Parkinson's disease (PD), and various other neurological diseases. Conventional drug delivery systems generally fail to cross the BBB, thus are inefficient in treatment. Although gradual development through research is ensuring the progress of nanotheranostic approaches from animal to human modeling, aspects of translational applicability and safety are a key concern. This demands a deep understanding of the interaction of body systems with nanomaterials. There are various plant-based nanobioactive compounds which are reported to have applicability in the diagnosis and treatment of these NDs. This review article provides an overview of applications of nanotheranostics in AD and PD. The review also discusses nano-enabled drug delivery systems and their current and potential applications for the treatment of various NDs.

3.
Curr Pharm Des ; 25(24): 2637-2649, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31603057

RESUMO

BACKGROUND: Multimodal imaging plays an important role in the diagnosis of brain disorders. Neurological disorders need to be diagnosed at an early stage for their effective treatment as later, it is very difficult to treat them. If possible, diagnosing at an early stage can be much helpful in curing the disease with less harm to the body. There is a need for advanced and multimodal imaging techniques for the same. This paper provides an overview of conventional as well as modern imaging techniques for brain diseases, specifically for tumor imaging. In this paper, different imaging modalities are discussed for tumor detection in the brain along with their advantages and disadvantages. Conjugation of two and more than two modalities provides more accurate information rather than a single modality. They can monitor and differentiate the cellular processes of normal and diseased condition with more clarity. The advent of molecular imaging, including reporter gene imaging, has opened the door of more advanced noninvasive detection of brain tumors. Due to specific optical properties, semiconducting polymer-based nanoparticles also play a pivotal role in imaging tumors. OBJECTIVE: The objective of this paper is to review nanoparticles-mediated brain imaging and disease prognosis by conventional as well as modern modal imaging techniques. CONCLUSION: We reviewed in detail various medical imaging techniques. This paper covers recent developments in detail and elaborates a possible research aspect for the readers in the field.


Assuntos
Encéfalo/diagnóstico por imagem , Imagem Molecular/tendências , Nanopartículas , Neuroimagem/tendências , Humanos , Prognóstico
4.
Mol Neurobiol ; 55(4): 3224-3236, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28478508

RESUMO

Alzheimer's disease (AD) pathogenesis leads to the appearance of senile plaques due to the production and deposition of the ß-amyloid peptide (Aß). Superparamagnetic iron oxide nanoparticles (SPIONs) have potential role in the detection and imaging of Aß plaques in AD. SPIONs have shown appropriate potential in the diagnosis and treatment of AD. In the present study, the pharmacokinetics of SPIONs and its effect in the biochemical pathway of AD were analyzed using collected information. During analysis, the interaction of SPIONs with amyloid beta-42 (Aß42), a biomarker for AD progression, has been shown. Nodes represent the entities and edges represent the relation (interactions) of one node to another node. Aß42 and their interaction with other entities making up biochemical network are involved in AD mechanism in presence of SPION. The kinetic simulation was done to investigate pharmacokinetics of SPIONs for AD, where concentration was assigned of nanoparticles and other entities were applied as a kinetic irreversible simple Michaelis-Menten or mass action kinetics. Simulation was done in presence and absence of SPIONs to investigate pharmacokinetic effect in AD and explore the mechanism of Aß42 in presence of SPIONs. This study may lead to better understanding, which is required to target the metabolism of Aß42 peptide, a pivotal player in this pathology.


Assuntos
Peptídeos beta-Amiloides/farmacocinética , Dextranos/química , Nanopartículas de Magnetita/química , Fragmentos de Peptídeos/farmacocinética , Transdução de Sinais , Biologia de Sistemas , Doença de Alzheimer , Ouro/química , Humanos , Simulação de Acoplamento Molecular
5.
Mol Neurobiol ; 54(9): 7276-7296, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-27815831

RESUMO

Neurodegenerative diseases have been an unsolved riddle for quite a while; to date, there are no proper and effective curative treatments and only palliative and symptomatic treatments are available to treat these illnesses. The absence of therapeutic treatments for neurodegenerative ailments has huge economic hit and strain on the society. Pharmacotherapies and various surgical procedures like deep brain stimulation are being given to the patient, but they are only effective for the symptoms and not for the diseases. This paper reviews the recent studies and development of stem cell therapy for neurodegenerative disorders. Stem cell-based treatment is a promising new way to deal with neurodegenerative diseases. Stem cell transplantation can advance useful recuperation by delivering trophic elements that impel survival and recovery of host neurons in animal models and patients with neurodegenerative maladies. Several mechanisms, for example, substitution of lost cells, cell combination, release of neurotrophic factor, proliferation of endogenous stem cell, and transdifferentiation, may clarify positive remedial results. With the current advancements in the stem cell therapies, a new hope for the cure has come out since they have potential to be a cure for the same. This review compiles stem cell therapy recent conceptions in neurodegenerative and neurometabolic diseases and updates in this field. Graphical Absract ᅟ.


Assuntos
Doenças Metabólicas/terapia , Doenças Neurodegenerativas/terapia , Transplante de Células-Tronco/métodos , Animais , Humanos , Doenças Metabólicas/metabolismo , Doenças Metabólicas/patologia , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Transplante de Células-Tronco/tendências
6.
Acta Biomater ; 41: 1-16, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27265153

RESUMO

UNLABELLED: Nanoparticles (NPs) are playing a progressively more significant role in multimodal and multifunctional molecular imaging. The agents like Superparamagnetic iron oxide (SPIO), manganese oxide (MnO), gold NPs/nanorods and quantum dots (QDs) possess specific properties like paramagnetism, superparamagnetism, surface plasmon resonance (SPR) and photoluminescence respectively. These specific properties make them able for single/multi-modal and single/multi-functional molecular imaging. NPs generally have nanomolar or micromolar sensitivity range and can be detected via imaging instrumentation. The distinctive characteristics of these NPs make them suitable for imaging, therapy and delivery of drugs. Multifunctional nanoparticles (MNPs) can be produced through either modification of shell or surface or by attaching an affinity ligand to the nanoparticles. They are utilized for targeted imaging by magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT), positron emission tomography (PET), computed tomography (CT), photo acoustic imaging (PAI), two photon or fluorescent imaging and ultra sound etc. Toxicity factor of NPs is also a very important concern and toxic effect should be eliminated. First generation NPs have been designed, developed and tested in living subjects and few of them are already in clinical use. In near future, molecular imaging will get advanced with multimodality and multifunctionality to detect diseases like cancer, neurodegenerative diseases, cardiac diseases, inflammation, stroke, atherosclerosis and many others in their early stages. In the current review, we discussed single/multifunctional nanoparticles along with molecular imaging modalities. STATEMENT OF SIGNIFICANCE: The present article intends to reveal recent avenues for nanomaterials in multimodal and multifunctional molecular imaging through a review of pertinent literatures. The topic emphasises on the distinctive characteristics of nanomaterial which makes them, suitable for biomedical imaging, therapy and delivery of drugs. This review is more informative of indicative technologies which will be helpful in a way to plan, understand and lead the nanotechnology related work.


Assuntos
Imagem Molecular/métodos , Nanopartículas/química , Nanotecnologia/métodos , Animais , Humanos , Imagem Multimodal , Nanopartículas/ultraestrutura
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