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1.
Front Med (Lausanne) ; 10: 1195026, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37915327

RESUMO

Background: Correlative interactions between electrical charges and cancer cells involve important unknown factors in cancer diagnosis and treatment. We previously reported the intrinsic suppressive effects of pure positive electrostatic charges (PEC) on the proliferation and metabolism of invasive cancer cells without any effect on normal cells in cell lines and animal models. The proposed mechanism was the suppression of pro-caspases 3 and 9 with an increase in Bax/Bcl2 ratio in exposed malignant cells and perturbation induced in the KRAS pathway of malignant cells by electrostatic charges due to the phosphate molecule electrostatic charge as the trigger of the pathway. This study aimed to examine PECs as a complementary treatment for patients with different types of solid metastatic tumors, who showed resistance to chemotherapy and radiotherapy. Methods: In this study, solid metastatic tumors of the end-stage patients (n = 41) with various types of cancers were locally exposed to PEC for at least one course of 12 days. The patient's signs and symptoms, the changes in their tumor size, and serum markers were followed up from 30 days before positive electrostatic charge treating (PECT) until 6 months after the study. Results: Entirely, 36 patients completed the related follow-ups. Significant reduction in tumor sizes and cancer-associated enzymes as well as improvement in cancer-related signs and symptoms and patients' lifestyles, without any side effects on other tissues or metabolisms of the body, were observed in more than 80% of the candidates. Conclusion: PECT induced significant cancer remission in combination with other therapies. Therefore, this non-ionizing radiation would be a beneficial complementary therapy, with no observable side effects of ionizing radiotherapy, such as post-radiation inflammation.

2.
Macromol Biosci ; 23(9): e2300181, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37399543

RESUMO

Pure positive electrostatic charges (PPECs) show suppressive effect on the proliferation and metabolism of invasive cancer cells without affecting normal tissues. PPECs are used for the delivery of drug-loaded polymeric nanoparticles (DLNs) capped with negatively charged poly(lactide-co-glycolide) (PLGA) and Poly(vinyl-alcohol) PVA into the tumor site of mouse models. The charged patch is installed on top of the skin in the mouse models' tumor region, and the controlled selective release of the drug is assayed by biochemical, radiological, and histological experiments on both tumorized models and normal rats' livers. It is found that DLNs synthesized by PLGA show great attraction to PPECs due to their stable negative charges, which would not degrade immediately in blood. The burst and drug release after less than 48h of this synthesized DLNs are 10% and 50%, respectively. These compounds can deliver the loaded-drug into the tumor site with the assistance of PPECs, and the targeted-retarded release will take place. Hence, local therapy can be achieved with much lower drug concentration (conventional chemotherapy [2 mg kg-1 ] versus DLNs-based chemotherapy [0.75 mg kg-1 ]) with negligible side effects in non-targeted organs. PPECs have many potential clinical applications for advanced-targeted chemotherapy with the lowest discernible side effects.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Camundongos , Ratos , Animais , Sistemas de Liberação de Medicamentos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/metabolismo , Eletricidade Estática , Antineoplásicos/química , Polímeros/uso terapêutico , Neoplasias/tratamento farmacológico , Nanopartículas/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos
3.
Diagnostics (Basel) ; 13(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36672989

RESUMO

A gigahertz (GHz) range antenna formed by a coaxial probe has been applied for sensing cancerous breast lesions in the scanning platform with the assistance of a suction tube. The sensor structure was a planar central layer and a metallic sheath of size of 3 cm2 connected to a network analyzer (keySight FieldFox N9918A) with operational bandwidth up to 26.5 GHz. Cancer tumor cells have significantly higher water content (as a dipolar molecule) than normal breast cells, changing their polarization responses and dielectric losses to incoming GHz-based stimulation. Principal component analysis named S11, related to the dispersion ratio of the input signal, is used as a parameter to identify malignant tumor cells in a mouse model (in vivo) and tumor specimens of breast cancer patients (in vitro) (both central and marginal parts). The results showed that S11 values in the frequency range from 5 to 6 GHz were significantly higher in cancer-involved breast lesions. Histopathological analysis was the gold standard for achieving the S11 calibration to distinguish normal from cancerous lesions. Our calibration on tumor specimens presented 82% positive predictive value (PPV), 100% negative predictive value (NPV), and 86% accuracy. Our goal is to apply this system as an in vivo non-invasive tumor margin scanner after further investigations in the future.

4.
Cancer Med ; 10(21): 7475-7491, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34626092

RESUMO

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.


Assuntos
Proliferação de Células , Metástase Neoplásica/patologia , Metástase Neoplásica/terapia , Eletricidade Estática , Animais , Apoptose , Linhagem Celular Tumoral , Modelos Animais de Doenças , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/radioterapia , Necrose , Gradação de Tumores
5.
Biomater Sci ; 9(18): 6214-6226, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34357368

RESUMO

A new biosensor for detecting cancer involved sentinel lymph nodes has been developed via the electrochemical tracing of fatty acid oxidation as a distinct metabolism of malignant cells invading lymph nodes (LNs). The system included integrated platinum needle electrodes that were decorated by carbon nanotubes (as hydrophobic agents) through laser-assisted nanowelding. It was applied to record the dielectric spectroscopy data from LN contents via electrochemical impedance spectroscopy. The system was applied for dielectric spectroscopy of LN contents via electrochemical impedance approach. The reduced lipid content of involved LNs, due to fat metabolism by invasive cancer cells, would decrease the charge transfer resistance (RCT) of the LNs with respect to their normal counterparts. Multi-walled carbon nanotubes (MWCNTs) with superhydrophobic properties were used to enhance the interaction of Pt needle electrodes with the lipidic contents of lymph nodes. This is the first time that a fatty acid metabolism-based sensing approach has been introduced to detect involved LNs. Moreover, a novel electrode decorating method was applied to enhance the interfacial contact of this lipid detection probe (LDP). In order to avoid doubt about the biocompatibility of ferrocyanide, [Fe(CN)6]4- and ferricyanide, [Fe(CN)6]3-, a biocompatible injectable metal ion-based material, ferric carboxymaltose, was selected and applied as the electrolyte for the first time. Rabbit LNs were tested using the LDP in the animal model phase. The system was then used in vitro on 122 dissected human LNs in the operating room. Calibration of the results showed an excellent match between the dielectric response of the LDP (known as charge transfer resistance (RCT)) and the final pathological diagnoses. The LDP may have a promising future after further clinical investigations for intra-operative distinction between normal and cancerous LNs.


Assuntos
Técnicas Biossensoriais , Nanotubos de Carbono , Neoplasias , Animais , Técnicas Eletroquímicas , Eletrodos , Lasers , Linfonodos , Agulhas , Platina , Coelhos
6.
J Med Eng Technol ; 45(7): 505-510, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34184593

RESUMO

The transport properties of a molecular bio-electronic device based on the alanine amino-acid are investigated. The considered device consists of an alanine molecule as the central potential-dot coupled to two zigzag graphene nanoribbon (ZGNR) conducting electrodes. The current-voltage characteristics of this dual tunnelling molecular junction are studied at two different optimised compositions of the central molecule. The proposed amino-acid based structure utilises the tunnelling coupling similar to that of semiconducting single-electron transistors (SETs) to avoid complications due to the atomic interfaces. The current-voltage characteristics show polarity-dependent behaviour making the device feasible of being applied as a molecular rectifier. Negative differential resistance (NDR) along with tuneable peak-current position has been also observed in the current-voltage characteristics. The device is also capable of being applied as a switch controllable by the central molecule orientation.


Assuntos
Grafite , Nanotubos de Carbono , Alanina , Eletrodos
7.
Nanoscale ; 12(43): 22129-22139, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33119020

RESUMO

Herein, we present a new design on the Single Needle Electrochemical Therapy (SNEChT) method by introducing some major improvements, including a nanoporous platinum electrode, tunable in situ anode size that depends on the width and location of the tumor, and the capability of measuring the efficacy of therapy based in intra-therapeutic impedance recording by the same EChT needle. It could have significant implications in optimizing EChT operative conditions. The nanoporous Pt electrode increased the interactive surface with a tumor, and produced a higher amount of current with lower stimulating DC voltage. The tunable anode size prevents the over-acidification of treated or non-desired lesions. Hence, this feature reduced the over distribution of tissue. Monitoring the impedance during the therapy clearly informs us about the local destruction of the tumor in each location. Thus, we can be informed about the threshold of tissue acidosis with the lowest electrical stimulation. The insertion of one needle with a tunable anode length for both precise therapy and impedance-based intra-therapeutic monitoring will shed new light on the applications of EChT.


Assuntos
Terapia por Estimulação Elétrica , Nanoporos , Neoplasias , Impedância Elétrica , Eletroquímica , Eletrodos , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Platina
8.
Analyst ; 145(23): 7636-7645, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-32955530

RESUMO

Separation of cancerous from normal cells is of broad importance in a large number of cancer diagnosis and treatment methods. One of the most important factors to designate and specify different cells is to study their dielectric and electric cell membrane characteristics. In this research, a label-free cytological slide chip (CSC) is designed and fabricated based on AC electric field stimulation of breast cell lines and blood cells at low frequencies (1 kHz-200 kHz). The AC-CSC traps cells based on their dielectric polarization functions which is distinct between different phenotypes of breast cells and blood cells. We learned that by using AC electric fields, each breast cell line shows a capturing response to a specific range of frequencies. The progression in cancer phenotypes decreases the cell's polarizability. Hence, characteristic frequency responses were achieved for these cells. In this study, thermal potential and electrolysis which were the main bottle neck problems in DC applied fields were completely solved. The AC-CSC could be used in CTC separation from leukocytes, a test performed based on a compound with 1% cancer cells in white blood cells (1% MDA-MB-231 : 99% WBC) which results in 90% capturing efficiency of cancer cells. Frequency dependent capturing brings so much hope that smart slides will be useful at the clinical stage in the near future.


Assuntos
Células Neoplásicas Circulantes , Células Sanguíneas , Linhagem Celular Tumoral , Separação Celular , Humanos , Leucócitos , Fenótipo
9.
Biosens Bioelectron ; 165: 112421, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32729539

RESUMO

In this paper, freshly (non-fixed) dissected tissues obtained from breast cancer surgery were impedimetrically and pathologically scanned, analyzed, and probable electro-pathological mutual matching was investigated. A new electrical model was proposed for pathological scores of breast lesions based on the theory of electric current dispersion by different types of biological tissues. This integrated handheld bioimpedance sensor named EPA would score the clearance or malignancy involvement of dissected tumor margins by introducing two crucial classification parameters named Z1kHz and IPS (impedance phase slope in the frequency ranges of 100-500 kHz). EPA benefits from a precise signal recording and analysis method which leads to the detection of the presence of even about 5% distribution of premalignant cells among healthy breast tissue. EPA can be clinically used by pathologists, as a complementary device, for real-time diagnosis of suspicious margins of dissected tumors to declare more precise intraoperative diagnosis by scanning all around the dissected tissues. Each data sampling and analysis covers 2 mm of the surface in less than 5 s. Measurements on about 313 human breast tumor margins showed more than 90% accuracy and near 93% specificity for EPA as an independent diagnostic tool.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Mama , Neoplasias da Mama/diagnóstico , Espectroscopia Dielétrica , Impedância Elétrica , Humanos
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