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1.
J Vis Exp ; (209)2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39072649

RESUMEN

Neuromodulation can provide diagnostic, modulatory, and therapeutic applications. While extensive work has been conducted in the brain, modulation of the spinal cord remains relatively unexplored. The inherently delicate and mobile spinal cord tissue imposes constraints that make the precise implantation of neural probes challenging. Despite recent advances in neuromodulation devices, particularly flexible bioelectronics, opportunities to expand their use in the spinal cord have been limited by the surgical complexities of device implantation. Here, we provide a series of surgical protocols tailored specifically for the implantation of a custom-made optoelectronic device that interfaces with the spinal cord in rodents. The steps to place and anchor an optical shank on a specific segment of the spinal cord via two different surgical implantation methods are detailed here. These methods are optimized for a diverse range of devices and applications, which may or may not require direct contact with the spinal cord for optical stimulation. To elucidate the methodology, the vertebral anatomy is referenced first to identify prominent landmarks before making a skin incision. The surgical steps to secure an optical shank over the cervical spine in rodents are demonstrated. Procedures are then outlined for securing the optoelectronic device connected to the optical shank in a subcutaneous space away from the spinal cord, minimizing unnecessary direct contact. Behavioral studies comparing animals receiving the implants to those undergoing sham surgeries indicate that the optical shanks did not adversely affect hindlimb or forelimb function seven days post-implantation. The present work broadens the neuromodulation toolkit for use in future studies aimed at investigating various spinal cord interventions.


Asunto(s)
Médula Espinal , Animales , Médula Espinal/cirugía , Médula Espinal/fisiología , Ratas , Ratones
2.
Front Bioeng Biotechnol ; 10: 850571, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35721862

RESUMEN

In the case of the COVID-19 early diagnosis, numerous tech innovations have been introduced, and many are currently employed worldwide. But, all of the medical procedures for the treatment of this disease, up to now, are just limited to chemical drugs. All of the scientists believe that the major challenge toward the mortality of the COVID-19 patients is the out-of-control immune system activation and the subsequent cytokine production. During this process, the adaptive immune system is highly activated, and many of the lymphocytes start to clonally expand; hence many cytokines are also released. So, any attempt to harness this cytokine storm and calm down the immune outrage is appreciated. While the battleground for the immune hyperactivation is the lung ambient of the infected patients, the only medical treatment for suppressing the hypercytokinemia is based on the immunosuppressor drugs that systemically dampen the immunity with many unavoidable side effects. Here, we applied the alternating electric field to suppress the expansion of the highly activated lymphocytes, and by reducing the number of the renewed cells, the produced cytokines were also decreased. Applying this method to the blood of the COVID-19 patients in vitro showed ∼33% reduction in the average concentration of the three main cytokines after 4 days of stimulation. This method could carefully be utilized to locally suppress the hyperactivated immune cells in the lung of the COVID-19 patients without any need for systemic suppression of the immune system by the chemical drugs.

3.
Cancer Med ; 10(21): 7475-7491, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34626092

RESUMEN

BACKGROUND: We discovered that pure positive electrostatic charges (PECs) have an intrinsic suppressive effect on the proliferation and metabolism of invasive cancer cells (cell lines and animal models) without affecting normal tissues. METHODS: We interacted normal and cancer cell lines and animal tumors with PECs by connecting a charged patch to cancer cells and animal tumors. many biochemical, molecular and radiological assays were carried out on PEC treated and control samples. RESULTS: Correlative interactions between electrostatic charges and cancer cells contain critical unknown factors that influence cancer diagnosis and treatment. Different types of cell analyses prove PEC-based apoptosis induction in malignant cell lines. Flowcytometry and viability assay depict selective destructive effects of PEC on malignant breast cancer cells. Additionally, strong patterns of pyknotic apoptosis, as well as downregulation of proliferative-associated proteins (Ki67, CD31, and HIF-1α), were observed in histopathological and immunohistochemical patterns of treated mouse malignant tumors, respectively. Quantitative real-time polymerase chain reaction results demonstrate up/down-regulated apoptotic/proliferative transcriptomes (P21, P27, P53/CD34, integrin α5, vascular endothelial growth factor, and vascular endothelial growth factor receptor) in treated animal tumors. Expression of propidium iodide in confocal microscopy images of treated malignant tissues was another indication of the destructive effects of PECs on such cells. Significant tumor size reduction and prognosis improvement were seen in over 95% of treated mouse models with no adverse effects on normal tissues. CONCLUSION: We discovered that pure positive electrostatic charges (PECs) have an intrinsic suppressive effect on the proliferation and metabolism of invasive cancer cells (cell lines and animal models) without affecting normal tissues. The findings were statistically and observationally significant when compared to radio/chemotherapy-treated mouse models. As a result, this nonionizing radiation may be used as a practical complementary approach with no discernible side effects after passing future human model studies.


Asunto(s)
Proliferación Celular , Metástasis de la Neoplasia/patología , Metástasis de la Neoplasia/terapia , Electricidad Estática , Animales , Apoptosis , Línea Celular Tumoral , Modelos Animales de Enfermedad , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/metabolismo , Neoplasias Mamarias Experimentales/patología , Neoplasias Mamarias Experimentales/radioterapia , Necrosis , Clasificación del Tumor
4.
Biosens Bioelectron ; 183: 113194, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33813209

RESUMEN

While limited investigations have been reported on CTC elimination and its profits, recently, some new works were reported on detection followed by the destruction of CTCs. Limitations and complications of CTC capturing procedures have highly reduced the chance of selective destruction of CTCs in the bloodstream in the therapeutic guidelines of the patients. Here, we selectively deactivated the invasive function of CTCs during their circulation in the bloodstream by exposing the whole blood to pure positive electrostatic charge stimulation (PPECS). Our treatment suppressed pulmonary metastasis and extended the survival of the mice had been intravenously injected by electrostatically deactivated 4T1 breast cancer CTCs. Moreover, the number of cancerous lung nodules was drastically reduced in the mice injected by treated CTCs in comparison with the non-treated cohort. Evaluating the side effect of the PPECS on the blood components revealed no major effect on the functional properties of the white blood cells, and just a negligible fraction (∼10%) was damaged during this process. This approach does not need any capturing or targeting of CTCs from the blood as it is focused on perturbing the electrical function of negatively-charged tumor cells after being exposed to positive electrostatic charges. Taken together, continuous in-vivo deactivation of CTCs by PPECS with no requirement to complicated capturing protocols may improve the survival of cancer patients.


Asunto(s)
Técnicas Biosensibles , Neoplasias de la Mama , Células Neoplásicas Circulantes , Animales , Línea Celular Tumoral , Humanos , Ratones , Metástasis de la Neoplasia , Células Neoplásicas Circulantes/patología , Electricidad Estática
5.
RSC Adv ; 11(55): 34503-34515, 2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-35494759

RESUMEN

Concurrent with the pandemic announcement of SARS-CoV-2 infection by the WHO, a variety of reports were published confirming the cytokine storm as the most mortal effect of the virus on the infected patients. Hence, cytokine storm as an evidenced consequence in most of the COVID-19 patients could offer a promising opportunity to use blood as a disease progression marker. Here, we have developed a rapid electrochemical impedance spectroscopy (EIS) sensor for quantifying the overall immune activity of the patients. Since during the cytokine storm many types of cytokines are elevated in the blood, there is no need for specific detection of a single type of cytokine and the collective behavior is just measured without any electrode functionalization. The sensor includes a monolayer graphene on a copper substrate as the working electrode (WE) which is able to distinguish between the early and severe stage of the infected patients. The charge transfer resistance (R CT) in the moderate and severe cases varies about 65% and 138% compared to the normal groups, respectively and a specificity of 77% and sensitivity of 100% based on ELISA results were achieved. The outcomes demonstrate a significant correlation between the total mass of the three main hypercytokinemia associated cytokines including IL-6, TNF-α and IFN-γ in patients and the R CT values. As an extra application, the biosensor's capability for diagnosis of COVID-19 patients was tested and a sensitivity of 92% and specificity of 50% were obtained compared to the RT-PCR results.

6.
Biofabrication ; 13(3)2021 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-33126230

RESUMEN

Cell-imprinting technology is a novel method for directing stem cell fate using substrates molded from target cells. Here, we fabricated and studied cell-imprinted substrates for neural priming in human adipose-derived stem cells in the absence of chemical cues. We molded polydimethylsiloxane silicone substrates on fixed differentiated neural progenitor cells (ReNcellTMVM). The ReNcellTMcell line consists of immortalized human neural progenitor cells that are capable to differentiate into neural cells. The fabricated cell-imprinted silicone substrates represent the geometrical micro- and nanotopology of the target cell morphology. During the molding procedure, no transfer of cellular proteins was detectable. In the first test with undifferentiated ReNcellTMVM cells, the cell-imprinted substrates could accelerate neural differentiation. With adipose-derived stem cells cultivated on the imprinted substrates, we observed modifications of cell morphology, shifting from spread to elongated shape. Both immunofluorescence and quantitative gene expression analysis showed upregulation of neural stem cell and early neuronal markers. Our study, for the first time, demonstrated the effectiveness of cell-imprinted substrates for neural priming of adipose-derived stem cells for regenerative medicine applications.


Asunto(s)
Tejido Adiposo , Adipocitos , Bioimpresión , Diferenciación Celular , Humanos , Células-Madre Neurales , Neuronas
7.
Drug Deliv ; 26(1): 928-934, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31526074

RESUMEN

Artificial cavitation as a prerequisite of sonoporation, plays an important role on the ultrasound (US) assisted drug delivery systems. In this study, we have proposed a new method of microbubble (MB) generation by local electrolysis of the medium. An integrated interdigital array of three-electrode system was designed and patterned on a nickel-coated quartz substrate and then, a short DC electrical pulse was applied that consequently resulted in distributed generation of microbubbles at the periphery of the electrodes. Growth of the carbon nanotube (CNT) nanostructures on the surface of the electrodes approximately increased the number of generated microbubbles up to 7-fold and decreased their average size from ∼20 µm for bare to ∼7 µm for CNT electrodes. After optimizing the three-electrode system, biocompatibility assays of the CNT electrodes stimulated by DC electrical micropulses were conducted. Finally, the effect of the proposed method on the sonoporation efficiency and drug uptake of breast cells were assessed using cell cycle and Annexin V/PI flow cytometry analysis. These results show the potential of electrochemical generation of MBs by CNT electrodes as an easy, available and promising technique for artificial cavitation and ultrasound assisted drug delivery.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Nanotubos de Carbono/química , Neoplasias/tratamiento farmacológico , Permeabilidad/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos/métodos , Electrodos , Humanos , Microburbujas
8.
Adv Healthc Mater ; 8(17): e1900613, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31328442

RESUMEN

Production of local microbubbles (MBs) with dense distribution in tumor environment is achieved by developing an integrated electrochemical stimulator on a microfabricated silicon needle covered by zinc-oxide nanowires (ZnONWs). MBs are then exploded by external ultrasonic actuation, which induce microcavitations in tumor cells followed by direct entrance of anticancer drugs into cancer cells. This system, named ZnO nanowire-based microbubble generator probe (ZnONW-MGP), is tested on tumorized mice models (by MC4L2 breast cell lines). Mice treated by ZnONW-MGP have ≈82% reduction in tumor size within 10 days with just 25% of conventional dose of paclitaxel while in the absence of the system, they have just a 15% reduction in tumor size. Presence of ZnO nanostructures on microneedles strongly reduces the size of MBs and enhances the efficacy of the sonoporation.


Asunto(s)
Sistemas de Liberación de Medicamentos , Microburbujas , Agujas , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Ultrasonografía , Animales , Materiales Biocompatibles/química , Línea Celular Tumoral , Femenino , Humanos , Ratones Endogámicos BALB C , Nanocables/química , Nanocables/ultraestructura , Metástasis de la Neoplasia , Óxido de Zinc/química
9.
Adv Biosyst ; 3(7): e1800294, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-32648669

RESUMEN

It is increasingly being accepted that cells' physiological functions are substantially dependent on the mechanical characteristics of their surrounding tissue. This is mainly due to the key role of biomechanical forces on cells and their nucleus' shapes, which have the capacity to regulate chromatin conformation and thus gene regulations. Therefore, it is reasonable to postulate that altering the biomechanical properties of tissue may have the capacity to change cell functions. Here, the role of cell stretching (as a model of biomechanical variations) is probed in cell migration and invasion capacity using human normal and cancerous breast cells. By several analyses (i.e., scratch assay, invasion to endothelial barrier, real-time RNA sequencing, confocal imaging, patch clamp, etc.), it is revealed that the cell-stretching process could increase the migration and invasion capabilities of normal and cancerous cells, respectively. More specifically, it is found that poststretched breast cancer cells are found in low grades of invasion; they substantially upregulate the expression of manganese-dependent superoxide dismutase (MnSOD) through activation of H-Ras proteins, which subsequently induce aerobic glycolysis followed by an overproduction of matrix metalloproteinases (MMP)-reinforced filopodias. Presence of such invadopodias facilitates targeting of the endothelial layer, and increased invasive behaviors in breast cells are observed.


Asunto(s)
Neoplasias de la Mama/metabolismo , Regulación Neoplásica de la Expresión Génica , Glucólisis , Proteínas de Neoplasias/biosíntesis , Transducción de Señal , Estrés Mecánico , Neoplasias de la Mama/patología , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , Células MCF-7
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