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1.
Analyst ; 146(10): 3225-3233, 2021 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-33999068

RESUMEN

One of the best strategies to circumvent drug resistance is the employment of nanocarriers. For the current study, we have employed a nanoemulsion formulation of paclitaxel (PTX) to bypass drug resistance in the MDA-MB-231 cell line and impedance sensing biosensors to determine the exact time that PTX-NE induced apoptosis. Our MTT results demonstrated that PTX treatment could not reduce MDA-MB-231 cell viability to IC50 even after three days. However, the employment of the reagent TPGS (inhibitor of drug resistance) combined with paclitaxel could partially obviate PTX resistance. Next, the nanoemulsion form of PTX (PTX-NE) was fabricated employing the essential oil of the Satureja khuzestanica plant and was characterized using DLS and TEM methods. Our data showed that after 72 hours, PTX-NE at 250 nM concentration could induce a 50% reduction in cell viability. Moreover, annexin/PI and cell cycle analysis confirmed the apoptotic effect of PTX-NE on cancer cells. Lastly, we measured the impedance of MDA-MB-231 cells treated with the free and nanoemulsion forms of PTX. A significant decrease in the mean impedance of PTX-NE treated cells could be observed after 40 hours. To conclude, we have demonstrated here that PTX-NE could circumvent resistance and induce apoptosis in PTX-resistant breast cancer cells, which could be inferred from their impedance measurement.


Asunto(s)
Técnicas Biosensibles , Neoplasias de la Mama , Apoptosis , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Impedancia Eléctrica , Humanos , Paclitaxel/farmacología
2.
Appl Opt ; 56(15): 4496-4504, 2017 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-29047882

RESUMEN

We demonstrate the analogue of electromagnetically induced transparency (EIT) in a metal-dielectric-metal (MDM) plasmonic waveguide. Plasmonic induced transparency is a method similar to EIT. In this paper, a plasmonic MDM waveguide is proposed by using an ellipse shaped side-coupled ring resonator and simulated by finite difference time domain. Plasmonics as a new field of chip-scale technology is an interesting substrate, which is used to propose and numerically investigate a novel MDM structure. The aforementioned framework is a 2×2 plasmonic ring resonator, employing gold as a metal and polymethyl methacrylate as a dielectric. Simulations show that a transparent window is located at 1550 nm and signal wavelength is assumed to be 860 nm, which is the phenomenon of plasmonic induced transparency. The velocity of the plasmonic mode can be considerably slowed while propagating along the MDM bends. Our proposed configuration may thus be applied to storing and stopping light in plasmonic waveguide bends. This plasmonic waveguide system may find important applications for multichannel plasmonic filters, nano-scale optical switching, delay time devices, and slow-light devices in highly integrated optical circuits and networks. In comparison with our previous theoretical work based on circular shaped ring resonators, it is shown that ellipse shaped ring resonators demonstrate better specifications with a slow down factor estimated to be more than 30.

3.
Appl Opt ; 53(6): 1228-36, 2014 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-24663324

RESUMEN

This paper demonstrates the effects of applying magnetic and electric fields and physical dimensions alterations on AlGaAs/GaAs multiple quantum well (QW) slow light devices. Physical parameters include quantum well sizes and number of quantum wells. To the best of our knowledge, this is the first analysis of the effects of both applying magnetic/electric fields and physical parameters alterations and the first suggestion for matching the prefabrication and post fabrication tuning of the slow light devices based on excitonic population oscillations. The aim of our theoretical analysis is controlling the optical properties such as central frequency, bandwidth, and slow down factor (SDF) in slow light devices based on excitonic population oscillation to achieve better tuning. To reach these purposes, first we investigate the quantum well size and number of quantum wells alteration effects. Next, we analyze the effects of applying magnetic and electric fields to the multiple quantum well structure, separately. Finally, physical parameters and applied external fields are changed for measuring frequency shift and SDF for coherent population oscillation slow light devices. The results show the available central frequency shifts in about 1.6 THz at best. Also the SDF value improvement is about one order of magnitude. These results will be applicable for optical nonlinearity enhancements, all-optical signal processing, optical communications, all-optical switches, optical modulators, and variable true delays.

4.
J Phys Chem C Nanomater Interfaces ; 128(39): 16563-16575, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39380975

RESUMEN

In this study, a widely used colloid of Creighton AgNPs (ORI, 1-100 nm, mostly ≤ 40 nm, ∼10 µg mL-1) was rapidly manipulated via tangential flow filtration (TFF) for highly reproducible surface-enhanced (resonance) Raman spectroscopy (SE(R)RS) experiments down to the single-molecule (SM) level. The quasi-spherical AgNPs were size-selected, purified, and concentrated in two TFF fractions of a cutoff diameter of ∼40 nm: AgNP ≤ 40 (∼900 µg mL-1) and AgNP ≥ 40 (∼100 µg mL-1). The SE(R)S-based sensing capabilities of the two TFF fractions were then tested under pre-resonance (632.8 nm) and resonance (532.1 nm) excitation conditions for rhodamine 6G (R6G, 10-6-10-15 M). Both TFF isolates, AgNP ≤ 40 and AgNP ≥ 40, were more effective in adsorbing the R6G analyte (≥91%) than the original colloid (≥78%) at submonolayer coverages. Furthermore, the surface enhancement factors (SEF) of the two TFF fractions were markedly superior to those of ORI under all excitation conditions. SERS at 632.8 nm: only AgNP ≥ 40 enabled the detection of R6G at 10-9 M and produced the largest SEF (2.1 × 106). SE(R)RS and SM-SERRS at 532.1 nm: AgNP ≥ 40 gave rise to the largest SEF values (2.5 × 1010) corresponding to the SM regime down to 10-15 M of R6G. Nevertheless, AgNP ≤ 40 compensated for the size-dependence of the electromagnetic enhancements by an increase in the silver concentration, which led to SEF values comparable to those of AgNP ≥ 40 through additional resonance enhancements. TFF resulted into a ∼100-fold increase (AgNP ≤ 40) in the number of negatively charged AgNPs that were available to electrostatically bridge R6G cations and form SERRS "hot-spots" (AgNP-R6G-AgNP) within the focal volume. Evidently, the interplay between AgNP size, AgNP concentration, and excitation wavelength governs the SE(R)RS enhancements. This study demonstrated that TFF can facilitate the ecofriendly isolation of spherical AgNPs of controlled morphological and plasmonic properties for further enhancing their sensing capabilities as SE(R)RS substrates.

5.
J Am Coll Surg ; 238(6): 1153-1165, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38372343

RESUMEN

BACKGROUND: Idiopathic granulomatous mastitis (IGM) is mostly described as an autoimmune disease with higher prevalence among Middle Eastern childbearing-age women. This study aimed to evaluate the best treatment of choice in patients with resistant or recurrent IGM. STUDY DESIGN: Patients with established recurrent or resistant IGM who were referred to the Breast Cancer Research Center from 2017 to 2020 were randomly assigned to either one of the following treatment groups: A (best supportive care), B (corticosteroids: prednisolone), and C (methotrexate and low-dose corticosteroids). This adaptive clinical trial evaluated radiological and clinical responses, as well as the potential side effects, on a regular basis in each group, with patients followed up for a minimum of 2 years. RESULTS: A total of 318 participants, with a mean age of 33.52 ± 6.77 years, were divided into groups A (10 patients), B (78 patients), and C (230 patients). In group A, no therapeutic response was observed; group B exhibited a mixed response, with 14.1% experiencing complete or partial responses, 7.7% maintaining stability, and 78.2% experiencing disease progression. Accordingly, groups A and B were terminated due to inadequate response. In group C, 94.3% achieved complete response, 3% showed partial remission, and 2.7% had no response to therapy. Among the entire patient cohort, 11.6% tested positive for antinuclear antibodies, 3.5% for angiotensin-converting enzyme, and 12.3% for erythema nodosum. Notably, hypothyroidism was a prevalent condition among the patients, affecting 7.2% of the cohort. The incidence of common side effects was consistent across all groups. CONCLUSIONS: The most effective treatment option for patients with recurrent or resistant IGM is a combination therapy involving steroids and disease-modifying antirheumatic drugs such as methotrexate.


Asunto(s)
Mastitis Granulomatosa , Metotrexato , Recurrencia , Humanos , Femenino , Mastitis Granulomatosa/tratamiento farmacológico , Mastitis Granulomatosa/diagnóstico , Adulto , Metotrexato/uso terapéutico , Prednisolona/uso terapéutico , Prednisolona/administración & dosificación , Quimioterapia Combinada , Resultado del Tratamiento , Glucocorticoides/uso terapéutico , Glucocorticoides/administración & dosificación
6.
Sci Rep ; 13(1): 16719, 2023 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-37794050

RESUMEN

HER2 is an important prognostic marker in breast cancer (BC) patients, which also plays a crucial role in their therapeutic plan. Consequently, a great desire is to thoroughly assess the patients based on their HER2 status. In the current study, we aimed to evaluate HER2-low breast cancer as a new subtype in the standard classification of BC patients and review its characteristics and survival rate in a tertiary center in Iran. We retrospectively evaluated disease-free survival (DFS), overall survival (OS), and clinicopathological characteristics of BC patients referred to the Cancer Research Center in Tehran, Iran from 1991 to 2022. Patients' clinical characteristics, including HER2 status, which is classified as HER2-low, HER2-positive, or HER2-negative, were obtained from prospectively maintained registries. Among the total 3582 recruited patients, 60.2%, 13.6%, and 26.2% were HER2-negative, HER2-low, and HER2-positive, respectively. HER2-positive patients showed a significantly higher Hazard Ratio (HR) for DFS (HR 1.44, 95% CI 1.01-2.05) and OS (HR 2.05, 95% CI 1.31-3.20), compared to HER2-low. Moreover, HER2-low and HER2-negative were found to show the same proportion of high-grade tumors (28 and 28.4%), while 40% of the HER2-positive tumors were high-grade. Accordingly, HER2-low patients had a lower metastasis risk than the others (P-value = 0.01). The Ki67 percentage was significantly lower in the HER2-low group compared to the HER2-positive (P-value < 0.001). HER2-low, a new subtype of HER2-status classification with distinct biological and clinicopathological traits, represented the highest survival rate and less invasive characteristics. This difference was statistically significant when compared to HER2-positive, but not when compared to HER2-negative.Research registration unique identifying number: NCT05754047.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Estudios Retrospectivos , Receptor ErbB-2 , Pronóstico , Tasa de Supervivencia , Irán
7.
Macromol Biosci ; 23(9): e2300181, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37399543

RESUMEN

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.


Asunto(s)
Antineoplásicos , Nanopartículas , Neoplasias , Ratones , Ratas , Animales , Sistemas de Liberación de Medicamentos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/metabolismo , Electricidad Estática , Antineoplásicos/química , Polímeros/uso terapéutico , Neoplasias/tratamiento farmacológico , Nanopartículas/química , Portadores de Fármacos/química , Liberación de Fármacos
8.
Diagnostics (Basel) ; 13(2)2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36672989

RESUMEN

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.

9.
Front Med (Lausanne) ; 10: 1195026, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37915327

RESUMEN

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.

10.
Health Sci Rep ; 5(6): e871, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36210881

RESUMEN

Background and aims: Thalassemia syndromes are the most common hemoglobinopathy globally related to blood transfusion and iron overload in the body. Splenectomy, excessive iron overload, and repeated exposure to antigens in blood transfusions can cause severe damage to the patient's immune system making the patient prone to frequent infection. This study evaluates the immune system status and infection rate in beta-thalassemia major patients receiving iron chelators. Methods: This descriptive cross-sectional study was performed in Rasoul-e-Akram Hospital on patients with a beta-thalassemia major who had iron overload due to frequent blood transfusions. The percentage of lymphocyte markers was determined by flow cytometry. Serum levels of immunoglobin were measured by nephelometric assay. Also, Nitro blue tetrazolium and dihydrorhodamine assays were used to evaluate the phagocytic function. Results: Of the 106 patients participating in this study, 59 (55.7%) and 47 (44.3%) are male and female, respectively. The mean age ± SD of participants was 24.7 ± 12.1 years with 4 to 55 years. There was no significant correlation between sex, the C3 and C4 complements, the lymphocyte markers, and the immunoglobulin levels. Furthermore, all of these variables increased significantly over 30 (p < 0.05). Moreover, there was a strong positive correlation between splenectomy and IgG immunoglobulin (p < 0.001) and CD16 (p = 0.005) lymphocyte marker. Conclusion: Iron chelator agents effectively improve patients' immune system with thalassemia major. The increase in IgG and IgM immunoglobulins levels is due to frequent blood transfusions, which stimulate the immune system.

11.
Biomater Sci ; 9(18): 6214-6226, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34357368

RESUMEN

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.


Asunto(s)
Técnicas Biosensibles , Nanotubos de Carbono , Neoplasias , Animales , Técnicas Electroquímicas , Electrodos , Rayos Láser , Ganglios Linfáticos , Agujas , Platino (Metal) , Conejos
12.
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
13.
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
14.
Biosens Bioelectron ; 165: 112435, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32729548

RESUMEN

COVID-19 is the shocking viral pandemics of this year which affected the health, economy, communications, and all aspects of social activities all over the world. Early diagnosis of this viral disease is very important since it can prevent lots of mortalities and care consumption. The functional similarities between COVID-19 and COVID-2 in inducing acute respiratory syndrome lightened our mind to find a diagnostic mechanism based on early traces of mitochondrial ROS overproduction as lung cells' dysfunctions induced by the virus. We designed a simple electrochemical sensor to selectively detect the intensity of ROS in the sputum sample (with a volume of less than 500 µl). Comparing the results of the sensor with clinical diagnostics of more than 140 normal and involved cases resulted in a response calibration with accuracy and sensitivity both 97%. Testing the sensor in more than 4 hospitals shed promising lights in ROS based real-time tracing of COVID-19 from the sputum sample.


Asunto(s)
Betacoronavirus/aislamiento & purificación , Técnicas Biosensibles/métodos , Infecciones por Coronavirus/diagnóstico , Técnicas Electroquímicas/métodos , Neumonía Viral/diagnóstico , Especies Reactivas de Oxígeno/análisis , Esputo/virología , Adulto , Anciano , Técnicas Biosensibles/instrumentación , COVID-19 , Infecciones por Coronavirus/virología , Diagnóstico Precoz , Técnicas Electroquímicas/instrumentación , Diseño de Equipo , Femenino , Humanos , Pulmón/química , Pulmón/virología , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/virología , SARS-CoV-2 , Sensibilidad y Especificidad , Esputo/química , Adulto Joven
15.
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
16.
ACS Sens ; 4(2): 353-362, 2019 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-30572702

RESUMEN

Actin and microtubules form cellular cytoskeletal network, which mediates cell shape, motility and proliferation and are key targets for cancer therapy. Changes in cytoskeletal organization dramatically affect mechanical properties of the cells and correlate with proliferative capacity and invasiveness of cancer cells. Changes in the cytoskeletal network expectedly lead to altered nonmechanical material properties including electrical conductivity as well. Here we applied, for the first time, microtubule and actin based electrical measurement to monitor changes in the electrical properties of breast cancer cells upon administration of anti-tubulin and anti-actin drugs, respectively. Semiconductive behavior of microtubules and conductive behavior of actins presented different bioelectrical responses (in similar frequencies) of the cells treated by anti-tubulin with respect to anti-actin drugs. Doped silicon nanowires were applied as the electrodes due to their enhanced interactive surface and compatibility with electronic fabrication process. We found that treatment with Mebendazole (MBZ), a microtubule destabilizing agent, decreases electrical resistance while treatment with Paclitaxel (PTX), a microtubule stabilizing agent, leads to an increase in electrical resistance. In contrast, actin destabilizing agents, Cytochalasin D (CytD), and actin stabilizing agent, Phalloidin, lead to an increased and decreased electrical resistance, respectively. Our study thus provides proof-of-principle of the usage of determining the electrical function of cytoskeletal compartments in grading of cancer as well as drug resistance assays.


Asunto(s)
Citoesqueleto/efectos de los fármacos , Citoesqueleto/metabolismo , Resistencia a Antineoplásicos , Conductividad Eléctrica , Electrofisiología/métodos , Actinas/química , Electrodos , Electrofisiología/instrumentación , Humanos , Células MCF-7 , Multimerización de Proteína/efectos de los fármacos
17.
Biosens Bioelectron ; 142: 111566, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31404879

RESUMEN

Cell free diagnosis of cancer is one of the crucial fields in new generation of medical technology. In this regard, cancer detection based on coastal fluids secreted from the tissues (named as secretome) has attracted a lot of attention. Lipids are important macromolecules could be found with much higher concentrations in secretome of cancer tissues vs. normal ones. On the other hand, lipids are the main dielectric components of the secretome with respect to proteins and ions. Here for the first time we introduced an electrochemical lipidomics based on electrical impedance spectroscopy (EIS) of the secretomes to detect the cancerous samples due to the lipidic content of their secretions. The EIS sensor was fabricated by multiwall carbon nanotube (MWCNT) arrays as conductive and super hydrophobic materials to have great interactive surface with the lipidic content of the solution. Results of the tests on the secretions of more than 100 human biopsied breast tissues showed the promising match between the charge transfer resistance (RCT) of samples' secretions and pathological states of the tissues with meaningful boundary (up to 8 kΩ for normal and more than 13 kΩ for cancer samples). Mass spectroscopic analyses confirmed the higher content of lipids in cancer secretomes. Electrical lipidomics of the secretome shed new lights in cell free cancer diagnosis and could be applied as a complementary clinical approach in all of biopsy based diagnoses in future.


Asunto(s)
Espectroscopía Dieléctrica/instrumentación , Metabolismo de los Lípidos , Lipidómica/instrumentación , Nanotubos de Carbono/química , Neoplasias/metabolismo , Microambiente Tumoral , Línea Celular Tumoral , Diseño de Equipo , Humanos , Nanotubos de Carbono/ultraestructura , Neoplasias/diagnóstico
18.
Biosens Bioelectron ; 118: 51-57, 2018 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-30055420

RESUMEN

Determining the migratory and invasive capacity of cancer cells as well as clarifying the underlying mechanisms are most relevant for developing biosensors in cancer diagnosis, prognosis, drug development and treatment. Intravasation of metastatic cells into blood stream initiated by their invasion to vascular layer would be a significant characteristic of metastasis. Many types of biochemical and bioelectrical sensors were developed for early detection of metastasis. The simplicity of the setup, the ease of the readout, detection of the trace of rare metastatic cells and the feasibility to perform the assay with standard laboratory equipment are some of the challenges limiting the usability of the sensors in tracing the metastasis. Here we describe a biosensor based on recently reported metastatic diagnosis assay; Metas-Chip, with the assistance of nanoroughened Poly-methyl methacrylate (PMMA) layer to diagnose populated metastatic breast cells from primary cancerous ones. Retraction and detachment of Human Umbilical Vein Endothelial Cells (HUVECs) invaded by metastatic cells as a recently found phenomena is the mechanism of the action. A population of HUVECs would be detached from the gold microelectrodes, patterned on nanoroughened surface, which would lead to large changes in impedance. Here, applying biocompatible and patternable nanoroughened surface instead of using adhesive layers which might produce electrical noises resulted in great sensitivity and detectivity of the sensor. Apart from the tight interaction between endothelial cells and nanocontacts of the electrodes, using low concentration (10%) of tumor cells in this invasion assay, might enhance its application in clinical trials.


Asunto(s)
Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Polimetil Metacrilato/química , Línea Celular Tumoral , Impedancia Eléctrica , Electrodos , Oro/química , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos
19.
J Res Med Sci ; 16(2): 184-7, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22091229

RESUMEN

BACKGROUND: The prevalence of Helicobacter pylori infection, which may increase the risk of gastritis, peptic ulcers, and cancer, has increased worldwide. This number is estimated to be around 70-90% in developing countries and 25-50% in developed countries. It is possible that the bacterium can be transmitted via food and water as well as zoonotically and iatrogenically. Because of high prevalence of this infection in Iran, the aim of this study is to examine whether H. pylori infection might be transmitted from cow's milk and faeces. METHODS: The existence of the H. pylori antibody and antigen was investigated in samples of serum, milk, and faeces from 92 lactating Holstein cows in Shahrekord, Iran. The H. pylori antigen and antibody were detected using ELISA and were confirmed by PCR. RESULTS: It was found that out of 92 serum specimens, 25 (27%) of the cows were positive for the H. pylori antibody and 67 specimens were negative. From these 25 seropositive cows, 10 (40%) faeces samples and four (16%) milk samples were antigen positive for H. pylori. Four of the antigen-positive milk specimens were also antigen positive for faeces. The existence of the UreC gene was also confirmed in positive samples of milk and faeces. CONCLUSIONS: There is a possibility that cow's milk is a transmission mode in H. pylori infection and faecal contamination and inappropriate management processes could transfer H. pylori to humans. The awareness of the H. pylori epidemiology and its method of distribution are necessary for public health measures and controlling the spread of this bacterium. Further investigation with a greater sample number is necessary to verify the ability of H. pylori transmission via milk consumption.

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