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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., The effect of pure electrostatic charges has been investigated on cultured normal and cancerous breast cell lines for the first time. The selective effect of positive electrostatic charges (PECs) on metastatic cell lines and animal tumors has been reported with no effect on normal tissues. PECs induce apoptosis in metastatic breast cancer cell lines and tumors by suppressing proifration pathways. More than 400 mouse models have been tested to investigate the effects of PECs on cancerous tumors and animal organs by different analyses. Survival analyses depict a high survival rate of treated mice with positive electrostatic charges compared to other conventional cancer treatments such as chemotherapy and radiotherapy.

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.

Background: The current research seeks to present a comparative study of the effect of filgrastim and pegfilgrastim in the treatment of fever and neutropenia in leukemia patients. Materials and Methods: The present study is a blind randomized clinical trial. The study population is comprised of 120 children with acute lymphoblastic leukemia (ALL) who were admitted to the hospital due to mild febrile neutropenia during 2019. Included patients were divided into two groups. Filgrastim (10 micrograms/ kilogram, daily subcutaneously) and pegfilgrastim (100 micrograms per kilogram of a subcutaneous dose) were used for groups, respectively. Fever monitored every 6 hours, and neutrophil count was performed every 48 hours. The questionnaire designed in the study included age, type of drug side effects, number of days of neutropenia, and fever cessation time. Then, the data were analyzed by SPSS software. Result: Leukemic children with fever and neutropenia (N=120) were included in the study, which was 59 (49.1%) male and 61 (50.9%) female by the mean age of 79±44 months. The mean days of neutropenia correction in the filgrastim and pegfilgrastim groups were 5 and 4 days, respectively, which was not significantly different (p =0.08). There was no correlation between patients’ complications and types of treatments (p>0.05). Muscular pain was the most common complication observed among 4 cases and 1 case following filgrastim and pegfilgrastim administration, respectively. Furthermore, hyperleukocytosis following pegfilgrastim consumption was observed in two cases. Conclusion: There was no significant correlation between the duration until the cessation of fever and the number of neutropenia days in the two groups receiving pegfilgrastim and filgrastim. Therefore, the fever and neutropenia improve with pegfilgrastim earlier than filgrastim; besides, fewer injections, patient comfort, and less musculoskeletal pain can be observed.

Objectives Osteoarthritis is a prevalent condition with a high level of disease burden. Some dietary regimens used in traditional medicine systems show promise as a treatment for osteoarthritis. The aim of this study was to assess the effect of a Persian food on the symptoms of osteoarthritis. Design A pilot non-randomised open-labeled clinical study Methods Patients with a diagnosis of osteoarthritis received 500 g chickpea broth (Nokhodāb) daily for the first five days, followed by the same amount per week for the next three weeks. The knee injury and osteoarthritis outcome score questionnaire and short-form World Health Organisation quality of life questionnaire were administered at baseline, day five and day thirty. The safety profile of the intervention was also assessed. Results Consumption of Nokhodāb was associated with improvements in pain, with a statistically significant decline in pain scores detected after 30 days (p = 0.005). Significant improvements in three of five quality of life domain scores were also reported at the same time point (p = 0.04). Conclusions The findings of this pilot study reveal a promising effect of Nokhodāb on pain and quality of life in patients with osteoarthritis. More definitive controlled trials are now needed to verify these findings.

The paper proposes a new fabrication method of a resistive gas sensor made of vertically aligned carbon nanotubes (CNT) by the perforated electrode. This new configuration can be also utilized with vertically aligned nanomaterial such as ZnO wires. This method contains two aspects, which are getting top electrical contact from MWCNTs and devising hexagonal pattern holes on the sensor surface to ease the gas flow through the sensor. Reaching ambient molecules to these dense CNT forests is always of the essence; also, the top electrical contact of the CNTs is a fabrication challenge. The high sensitivity of proposed CNT-based sensor is attributed to their collective large porous surface along with etched circular holes located at the apexes and center of a hexagonal pattern on sensor top contact. For optimal sensor performance, the simulation approach by ANSYS-FLUENT software has optimized circular holes diameters and distances. The fabrication process proposes an oxygenated plasma treated CNTs with top electrical contact devised by a certain simple method for the very first time. Top electrical contact has been fabricated possible by the procedure of immersing the CNTs in viscosity liquid and providing electrical contact using conductive paste. Well-aligned multi-walled carbon nanotubes (MWCNT) have been grown on glass substrate placed into DC-PECVD unit bearing approximately temperature of 350 °C. In this paper, the resistivity of carbon nanotubes at different temperatures for the ambient gas and linear sensitivity to oxygen gas has been investigated. The sensors with larger diameter nanotubes are more sensitive. Etching patterned holes with 200 μm diameter enhances the sensitivity up to 50%.

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., Highlights • A novel electrotechnical diagnosis system for fast screening of COVID-19 was developed. • It has been based on early tracing of reactive oxygen species (ROS) overproduction. • MWCNTs have a crucial role in selective detection of released ROS induced by the virus. • These impressive results were achieved while the sensor declared diagnosis in less than 30 s.

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.

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.

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.

This paper presents a novel method to improve the function of dye-sensitized solar cell (DSSC). The pro- posed method includes use of macro-porous silicon (PSi) as a photoanode for DSSC. The photoanode, PSi, was fabri- cated by a simple electrochemical anodization process. The effects of the obtained PSi-based photoanode on the DSSC performance are investigated by using photocurrent-volt- age, UV-visible spectroscopy, and reflectance spec- troscopy measurements. The results show that the macro- porous structure in the PSi-based photoanode not only increases internal surface area in the photoanode, but also functions as an anti-reflective/light-trapping layer. Macro- porous structure leads to the both enhancement of pho- toanode dye loading capacity and increasing the optical path length of the incident light inside the photoanode. This way, macro-porous structure plays an important role in the improvement of light harvesting efficiency. The optimal power conversion efficiency of 3.56 and 3.93 % (spin coated and sputtered TiO2 respectively) is obtained from the PSi-based DSSC, with 58 and 75 % improvement in the efficiency as compared to a fabricated conventional DSSC. The measurement results suggest that exploiting PSi in the structure of photoanode raises hopes for low-cost and high- performance production of hybrid Si/dye solar cells in the future.

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.

Modified rotating-jet electrospinning method (MRJM) is a new electrospinning technique with a novel setup including two metallic concentric hollow cylinders for generating highly aligned fibers. In this report, an experimental study was carried out to evaluate the effectiveness of MRJM for generating highly aligned nanofibers. For this purpose, the effect of voltage in the range of 10–22 kV, inner collector diameter in the range of 20–50 cm, and outer collector diameter in the range of 30–60 cm, on alignment degrees of electrospun fibers were explored and the results for each set of parameters were compared with those obtained for rotating-jet electrospinning method (RJM). The obtained results indicated that the alignment degrees of electrospun fibers in MRJM were significantly higher than those of RJM. The maximum achievable alignment degree in MRJM was around 82 % that was higher than the corresponding maximum value (40 %) of RJM. Although the effect of applied voltage on the degree of alignment in MRJM was observed to be negligible, it was experimentally proved that by manipulating the outer cylinder diameter, the degree of alignment can be increased up to 20 %. To achieve a conceptual understanding of the reason for significant influence of the outer cylinder on the elecrospinning performance, a formula was derived according to the Gauss’s law in the last part of this paper that relates the electric field strength inside the region between the inner cylinder and the spinneret to the radii of inner and outer cylinders.

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.

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.

In this paper we investigate the effects of quantum well size changes on slow light device properties. The principle properties such as center frequency and slow down factor of a slow light device are affected by changing the size of quantum well. In this way, the effects of quantum well size on Oscillator Strength and binding energy of exciton are considered separately. First, we investigate the variations in oscillator strength of exciton due to different quantum well size. Second, exciton binding energy level shift due to size of quantum well is investigated. According to this analysis, we have developed a new method for tuning slow light device bandwidth center frequency and slow down factor. Analysis and simulation of a basic GaAs/AlGaAs quantum wells optical slow light device based on excitonic population oscillation shows that size of quantum wells could tune both of the frequency properties and slow down factor of an optical slow light device. Simulation results show that slow down factor and oscillation strength of exciton are proportional to each other in direct manner. Moreover, decreasing the quantum well width, causes enhancement in binding energy of excitons. These achievements are useful in optical nonlinearity enhancements, all-optical signal processing applications and optical communications.

This paper investigates the effects of quantum well size changes on center frequency and slow down factor of an slow light device. In this way, we consider the quantum well size alteration effects on oscillator strength and binding energy of exciton. First, we investigate the variations in oscillator strength of exciton due to different quantum well size. Second, exciton binding energy level shift due to size of quantum well is investigated. According to this analysis, we have developed a new method for tuning slow light device bandwidth center frequency and slow down factor. Analysis and simulation of a basic GaAs/AlGaAs quantum wells optical slow light device based on excitonic population oscillation shows that size of quantum wells could tune both of the frequency properties and slow down factor of an optical slow light device. In our simulation with 34 quantum wells each with the width of 60?, we have received the slow down factor of more than 60,000. These achievements are useful in optical nonlinearity enhancements, all-optical signal processing applications and optical communications.

This article presents a novel method for growing multi walled carbon nanotubes (MWCNTs). The proposed method includes use of long zone (long distance between the anode and cathode electrodes) DC-PECVD at an ultra-low temperature. Through this method, the growth of vertically aligned CNTs (VACNT) with high aspect ratio at temperatures as low as 250°C was achieved. This method is based on M. K. Tabatabaei et al paper entitled “Remote and direct plasma regions for low-temperature growth of carbon nanotubes on glass substrates for display applications”. Simulation results proved thermal gradient along the reaction chamber used for low temperature growth. The structure and the properties of the grown CNTs were investigated using scanning electron microscopy and Raman spectroscopy. Also the electron field emission current was measured for CNTs with different diameters. As a catalyst, a thin layer (15 nm) of Ni was deposited on Indium Tin Oxide/glass substrate. Hydrogen and Acetylene were used as feed gases. Low temperature growth of VACNTs is suitable for low cost productions which enables use of low temperature substrates such as plastics and glass.

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.

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 zoo-notically 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 sam-ples were antigen positive for H. pylori. Four of the antigen-positive milk specimens were also antigen positive for fae-ces. 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 contami-nation and inappropriate management processes could transfer H. pylori to humans. The awareness of the H. pylori epi-demiology 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 transmis-sion via milk consumption.

We analyze an integrated electrically pumped opto-electronic mixer, which consists of two InP/GaInAs hetero junction bipolar transistors (HBT), in a cascode configuration. A new HBT with modified physical structure is proposed and simulated to improve the frequency characteristics of a cascode mixer. For the verification and calibrating software simulator, we compare the simulation results of a typical HBT, before modifying it and comparing it with empirical reported experiments. Then we examine the simulator on our modified proposed HBT to prove its wider frequency characteristics with better flatness and acceptable down conversion gain. Although the idea is examined in several GHz modulation, it may easily be extended to state of the art HBT cascode mixers in much higher frequency range.

Background: Combination therapy has generated remarkable motivation in the clinical setting since it boosts the therapeutic potential of anticancer drugs. Glioblastoma multiforme is the most common, aggressive malignant brain tumor which affects patients of all ages. This brain tumor is principally resistant to treatment. Methods: In this study, we combined temozolomide as a standard chemotherapeutic drug for human glioblastoma multiforme, with ciprofloxacin in an attempt to determine whether ciprofloxacin could potentiate the cytotoxic effects of temozolomide. The glioblastoma A-172 cell line was exposed to ciprofloxacin and temozolomide either alone or in combination for 24, 48 and 72 h. Cytotoxicity was measured by the MTT assay. Results: Ciprofloxacin and temozolomide induced tumor cell death in a dosedependent manner with an IC50 value of 259.3 μM for ciprofloxacin and 62.5 μM for temozolomide at 72 h. These values shifted to 22.8 μM for ciprofloxacin and 8.6 μM for temozolomide in the presence of the IC50 of the other drug. The combination index values were