Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 71
Filter
1.
Acc Chem Res ; 57(16): 2395-2413, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39101684

ABSTRACT

ConspectusGas sensors are used in various applications to sense toxic gases, mainly for enhanced safety. Resistive sensors are particularly popular owing to their ability to detect trace amounts of gases, high stability, fast response times, and affordability. Semiconducting metal oxides are commonly employed in the fabrication of resistive gas sensors. However, these sensors often require high working temperatures, bringing about increased energy consumption and reduced selectivity. Furthermore, they do not have enough flexibility, and their performance is significantly decreased under bending, stretching, or twisting. To address these challenges, alternative materials capable of operating at lower temperatures with high flexibility are needed. Two-dimensional (2D) materials such as MXenes and transition-metal dichalcogenides (TMDs) offer high surface area and conductivity owing to their unique 2D structure, making them promising candidates for realization of resistive gas sensors. Nevertheless, their sensing performance in pristine form is typically weak and unacceptable, particularly in terms of response, selectivity, and recovery time (trec). To overcome these drawbacks, several strategies can be employed to enhance their sensing properties. Noble-metal decoration such as (Au, Pt, Pd, Rh, Ag) is a highly promising method, in which the catalytic effects of noble metals as well as formation of potential barriers with MXenes or TMDs eventually contribute to boosted response. Additionally, bimetallic noble metals such as Pt-Pd and Au/Pd with their synergistic properties can further improve sensor performance. Ion implantation is another feasible approach, involving doping of sensing materials with the desired concentration of dopants through control over the energy and dosage of the irradiation ions as well as creation of structural defects such as oxygen vacancies through high-energy ion-beam irradiation, contributing to enhanced sensing capabilities. The formation of core-shell structures is also effective, creating numerous interfaces between core and shell materials that optimize the sensing characteristics. However, the shell thickness needs to be carefully optimized to achieve the best sensing output. To reduce energy consumption, sensors can operate in a self-heating condition where an external voltage is applied to the electrodes, significantly lowering the power requirements. This enables sensors to function in energy-constrained environments, such as remote or low-energy areas. An important advantage of 2D MXenes and TMDs is their high mechanical flexibility. Unlike semiconducting metal oxides that lack mechanical flexibility, MXenes and TMDs can maintain their sensing performance even when integrated onto flexible substrates and subjected to bending, tilting, or stretching. This flexibility makes them ideal for fabricating flexible and portable gas sensors that rigid sensors cannot achieve.

2.
BMC Plant Biol ; 24(1): 695, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39044125

ABSTRACT

The bacterial blight of wheat is an important global disease causing a significant decline in crop yield. Nanotechnology offers a potential solution for managing plant diseases. Therefore, this research aimed to investigate the effectiveness of silver nanoparticles (AgNPs) in controlling bacterial blight in 27 locally grown wheat cultivars. The study examined the impact of AgNPs at three distinct time points: 1, 3, and 5 days after the onset of the disease. Biochemical assay revealed that one day after applying the disease stress, the Inia cultivar had the highest amount of soluble protein (55.60 µg.g-1FW) content in the treatment without AgNPs. The Azadi cultivar, without AgNPs treatment, had the lowest amount of soluble protein content (15.71 µg.g-1FW). The Tabasi cultivar had the highest activity of the superoxide dismutase (SOD) (61.62 mM.g-1FW) with the combination treatment of AgNPs. On the other hand, the Karchia cultivar had the lowest SOD activity (0.6 mM.g-1FW) in the treatment of disease without AgNPs. Furthermore, three days after the application of stress, the Mahdavi cultivar had the highest amount of soluble protein content (54.16 µg.g-1FW) in the treatment of disease without AgNPs. The Niknejad cultivar had the highest activity of the SOD (74.15 mM.g-1FW) with the combined treatment of the disease without AgNPs. The Kavir cultivar had the lowest SOD activity (1.95 mM.g-1FW) and the lowest peroxidase (POX) activity (0.241 mM g-1FW min-1) in the treatment of the disease with AgNPs. Five days after exposure to stress, the Mahooti cultivar had the highest SOD activity (88.12 mM.g-1FW) with the combined treatment of the disease with AgNPs, and the Karchia cultivar had the lowest SOD activity (2.39 mM.g-1FW) in the treatment of the disease with AgNPs. Further, the results indicated that exposure to AgNPs could improve the antioxidant properties of wheat seeds in blight-infected and disease-free conditions in some cultivars.


Subject(s)
Metal Nanoparticles , Plant Diseases , Silver , Triticum , Triticum/microbiology , Triticum/drug effects , Silver/pharmacology , Plant Diseases/microbiology , Superoxide Dismutase/metabolism , Plant Proteins/metabolism
3.
RSC Adv ; 14(25): 17526-17534, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38818359

ABSTRACT

The synthesis techniques used for metal oxide semiconductors strongly influence their chemical, physical and gas sensing characteristics. In this context, hematite (α-Fe2O3) nanoparticles (NPs) were synthesized using two different techniques, namely, sol-gel (named HSG) and Pechini sol-gel (named HPSG). The average crystallite size and surface area were 15 nm and 76 m2 g-1 and 20 nm and 57 m2 g-1 for HPSG and HSG, respectively. Morphological studies showed that the HSG material was composed of ellipsoid-shaped particles, while the HPSG material had peanut-shaped particles with open pores and channels. The comparison between the sensing performances of HPSG and HSG toward ethanol indicated HPSG to be a better sensing material for ethanol detection. The HPSG sensor exhibited a response of 12 toward 500 ppm ethanol at 250 °C, a fast response time of 5 s and excellent selectivity. The enhanced characteristics were mainly related to the peculiar morphology with a porous nature, which led to more gas adsorption and diffusion. In addition to shape influence, the size of NPs also has an effect on the gas sensing performance. In fact, a decrease in the crystallite size led to an increase in the surface area of the material where the gas molecule-sensing layer interaction took place. The increase in the surface area created more interaction sites, and thus the sensitivity was improved. From these results, the HPSG sensor can be regarded as a promising candidate for ethanol detection.

4.
Biotechnol Prog ; : e3473, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38757348

ABSTRACT

Successful gene therapy relies on carriers to transfer genetic materials with high efficiency and low toxicity in a targeted manner. To enhance targeted cell binding and uptake, we developed and synthesized a new gene delivery vector based on graphene oxide (GO) modified by branched polyethyleneimine (BPEI) and folic acid (FA). The GO-PEI-FA nanocarriers exhibit lower toxicity compared to unmodified PEI, as well as having the potential to efficiently condense and protect pDNA. Interestingly, increasing the polymer content in the polyplex formulation improved plasmid transfer ability. Substituting graphene oxide for PEI at an N/P ratio of 10 in the HepG2 and THP1 cell lines improved hIL-12 expression by up to approximately eightfold compared to simple PEI, which is twice as high as GO-PEI-FA in Hek293 at the same N/P ratio. Therefore, the GO-PEI-FA described in this study may serve as a targeting nanocarrier for the delivery of the hIL-12 plasmid into cells overexpressing folic acid receptors, such as those found in hepatocellular carcinoma.

5.
Nanotechnology ; 35(33)2024 May 30.
Article in English | MEDLINE | ID: mdl-38744265

ABSTRACT

Transition metal dichalcogenides (TMDs) with a two-dimensional (2D) structure and semiconducting features are highly favorable for the production of NH3gas sensors. Among the TMD family, WS2, WSe2, MoS2, and MoSe2exhibit high conductivity and a high surface area, along with high availability, reasons for which they are favored in gas-sensing studies. In this review, we have discussed the structure, synthesis, and NH3sensing characteristics of pristine, decorated, doped, and composite-based WS2, WSe2, MoS2, and MoSe2gas sensors. Both experimental and theoretical studies are considered. Furthermore, both room temperature and higher temperature gas sensors are discussed. We also emphasized the gas-sensing mechanism. Thus, this review provides a reference for researchers working in the field of 2D TMD gas sensors.

6.
Med J Islam Repub Iran ; 38: 13, 2024.
Article in English | MEDLINE | ID: mdl-38586501

ABSTRACT

Background: Obesity and Helicobacter pylori (H. pylori) infection are public health problems in the world and Iran. This study aimed to indicate the anatomical place with the most accurate results for H. pylori. According to gastric mapping, this study will be able to evaluate the prevalence of H. pylori based on the pathology of gastric mapping and the accuracy of the antral rapid urease test (RUT) based on endoscopic findings. Methods: In this cross-sectional study, upper digestive endoscopy and gastric pathology were studied in 196 obese patients candidates for bariatric surgery. Statistical analyses were performed using a t-test and Chi-square/fisher's exact test to compare the groups. Sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), negative likelihood ratio (NLR), and odds ratio (OR) were used to compare RUT and pathological H. pylori test of each of the six areas of the stomach. We set a positive test of the pathology of 6 regions of the stomach as our gold standard (in this study). Results: The most common area of the stomach for pathological findings of H. pylori were incisura (116, 59.2%), greater curvature of the antrum (115, 58.3%), lesser curvature of the antrum (113, 57.7%), lesser curvature of the corpus (112, 57.1%), greater curvature of the corpus (111, 56.6%) and cardia (103, 52.6%). The prevalence of H. pylori was 58.2% (114 cases) and 61.2% (120 cases) with RUT and gastric pathology, respectively. Mild, moderate, and severe infection of H. pylori in cardia (58, 29.6%), greater and lesser curvature of the antrum (61, 31.1%), and greater curvature of the antrum (37, 18.9%) had the highest percentages of incidence comparing to other sites of the stomach, respectively. The most sensitive area for pathologic biopsy was incisura (96.6%, 95% confidence interval: 91.7, 98.7). Conclusion: According to the highest sensitivity, PLR, NPV, and pathological findings of H. pylori in accordance with the lowest NLR in the incisura compared with other parts of the stomach, it is highly recommended to take the biopsy from the incisura instead of other anatomical places of stomach for detecting H. pylori specifically if our strategy is taking only one biopsy.

7.
Chemosphere ; 352: 141234, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38278446

ABSTRACT

Gas sensors are extensively employed for monitoring and detection of hazardous gases and vapors. Many of them are produced on rigid substrates, but flexible and wearable gas sensors are needed for intriguing usage including the internet of things (IoT) and medical devices. The materials with the greatest potential for the fabrication of flexible and wearable gas sensing devices are two-dimensional (2D) semiconducting nanomaterials, which consist of graphene and its substitutes, transition metal dichalcogenides, and MXenes. These types of materials have good mechanical flexibility, high charge carrier mobility, a large area of surface, an abundance of defects and dangling bonds, and, in certain instances adequate transparency and ease of synthesis. In this review, we have addressed the different 2D nonmaterial properties for gas sensing in the context of fabrication of flexible/wearable gas sensors. We have discussed the sensing performance of flexible/wearable gas sensors in various forms such as pristine, composite and noble metal decorated. We believe that content of this review paper is greatly useful for the researchers working in the research area of fabrication of flexible/wearable gas sensors.


Subject(s)
Nanostructures , Transition Elements , Wearable Electronic Devices , Nanostructures/chemistry , Metals , Gases
8.
Environ Sci Pollut Res Int ; 30(57): 120236-120249, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37938488

ABSTRACT

The present study reported a green approach for the sonochemical-assisted synthesis (SAS) of copper oxide nanoparticles (CuO NPs) by using the aqueous extract of the Ficus johannis plant. The aqueous extract was obtained using ultrasonic-assisted extraction (15 min, 45 °C) and microwave-assisted extraction (15 min, 450 w). Next, the as-prepared extracts were used in a plant-mediated approach for the green synthesis of CuO NPs. The synthesized CuO NPs have been characterized via different techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), dynamic light scattering (DLS), ultraviolet-visible absorption, photoluminescence, and Fourier-transformed infrared (FT-IR) spectroscopic techniques. As observed, a broad absorption band around 375 nm clarified the successful synthesis of CuO NPs. From the SEM analysis, the average particle size of the prepared CuO NPs was estimated below 50 nm. In addition, the antimicrobial, antioxidant, and antifungal properties of the aqueous extracts as well as the as-prepared CuO NPs were evaluated by different assays. These included the release of protein, nucleic acids, disk diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and time-killing assays.


Subject(s)
Metal Nanoparticles , Nanoparticles , Copper/chemistry , Anti-Bacterial Agents/chemistry , Metal Nanoparticles/chemistry , Spectroscopy, Fourier Transform Infrared , Plant Extracts/pharmacology , Plant Extracts/chemistry , Oxides , X-Ray Diffraction , Microbial Sensitivity Tests
9.
Sensors (Basel) ; 23(21)2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37960529

ABSTRACT

Owing to their large surface area, two-dimensional (2D) semiconducting nanomaterials have been extensively studied for gas-sensing applications in recent years. In particular, the possibility of operating at room temperature (RT) is desirable for 2D gas sensors because it significantly reduces the power consumption of the sensing device. Furthermore, RT gas sensors are among the first choices for the development of flexible and wearable devices. In this review, we focus on the 2D MXenes used for the realization of RT gas sensors. Hence, pristine, doped, decorated, and composites of MXenes with other semiconductors for gas sensing are discussed. Two-dimensional MXene nanomaterials are discussed, with greater emphasis on the sensing mechanism. MXenes with the ability to work at RT have great potential for practical applications such as flexible and/or wearable gas sensors.

10.
Materials (Basel) ; 16(18)2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37763510

ABSTRACT

Metal oxide nanowires (NWs) with a high surface area, ease of fabrication, and precise control over diameter and chemical composition are among the best candidates for the realization of resistive gas sensors. Among the different techniques used for the synthesis of materials with NW morphology, approaches based on the vapor-liquid-solid (VLS) mechanism are very popular due to the ease of synthesis, low price of starting materials, and possibility of branching. In this review article, we discuss the gas-sensing features of metal oxide NWs grown by the VLS mechanism, with emphasis on the growth conditions and sensing mechanism. The growth and sensing performance of SnO2, ZnO, In2O3, NiO, CuO, and WO3 materials with NW morphology are discussed. The effects of the catalyst type, growth temperature, and other variables on the morphology and gas-sensing performance of NWs are discussed.

11.
J Hazard Mater ; 459: 132153, 2023 Oct 05.
Article in English | MEDLINE | ID: mdl-37506649

ABSTRACT

This study addresses the concerns regarding the cross-sensitivity of metal oxide sensors by building an array of sensors and subsequently utilizing machine earning techniques to analyze the data from the sensor arrays. Sensors were built using In2O3, Au-ZnO, Au-SnO2, and Pt-SnO2 and they were operated simultaneously in the presence of 25 different concentrations of nitrogen dioxide (NO2), carbon monoxide (CO), and their mixtures. To investigate the effects of humidity, experiments were conducted to detect 13 distinct CO and NO2 gas combinations in atmospheres with 40% and 90% relative humidity. Principal component analysis was performed for the normalized resistance variation collected for a particular gas atmosphere over a certain period, and the results were used to train deep neural network-based models. The dynamic curves produced by the sensor array were treated as pixelated images and a convolutional neural network was adopted for classification. An accuracy of 100% was achieved using both models during cross-validation and testing. The results indicate that this novel approach can eliminate the time-consuming feature extraction process.

12.
Eur J Neurosci ; 58(4): 3058-3073, 2023 08.
Article in English | MEDLINE | ID: mdl-37408361

ABSTRACT

Many neural areas, where patterned activity is lost following deafness, have the capacity to become activated by the remaining sensory systems. This crossmodal plasticity can be measured at perceptual/behavioural as well as physiological levels. The dorsal zone (DZ) of auditory cortex of deaf cats is involved in supranormal visual motion detection, but its physiological level of crossmodal reorganisation is not well understood. The present study of early-deaf DZ (and hearing controls) used multiple single-channel recording methods to examine neuronal responses to visual, auditory, somatosensory and combined stimulation. In early-deaf DZ, no auditory activation was observed, but 100% of the neurons were responsive to visual cues of which 21% were also influenced by somatosensory stimulation. Visual and somatosensory responses were not anatomically organised as they are in hearing cats, and fewer multisensory neurons were present in the deaf condition. These crossmodal physiological results closely correspond with and support the perceptual/behavioural enhancements that occur following hearing loss.


Subject(s)
Auditory Cortex , Deafness , Hearing Loss , Humans , Auditory Cortex/physiology , Neurons/physiology , Neuronal Plasticity/physiology
13.
Sci Rep ; 13(1): 7136, 2023 May 02.
Article in English | MEDLINE | ID: mdl-37130889

ABSTRACT

In this paper, we have developed an in-vehicle wireless driver breath alcohol detection (IDBAD) system based on Sn-doped CuO nanostructures. When the proposed system detects the ethanol trace in the driver`s exhaled breath, it can alarm and then prevents the car to be started and also sends the location of the car to the mobile phone. The sensor used in this system is a two-sided micro-heater integrated resistive ethanol gas sensor fabricated based on Sn-doped CuO nanostructures. Pristine and Sn-doped CuO nanostructures were synthesized as the sensing materials. The micro-heater is calibrated to provide the desired temperature by applying voltage. The results showed that by Sn-doping in CuO nanostructures, the sensor performance can be significantly improved. The proposed gas sensor has a fast response, good repeatability along with good selectivity that makes it suitable for being used in practical applications such as the proposed system.

14.
J Bank Financ ; 147: 106419, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36405518

ABSTRACT

This paper examines the resilience of banks as perceived by market participants during the COVID-19 crisis. We analyse how bank stock returns during January-March 2020 relate to the pre-crisis activation of macroprudential policy across 52 countries in a cross-sectional dimension. We find that, overall, a tighter macroprudential policy stance is beneficial for bank systemic risk, as assessed by equity market investors. A robust finding is that a perceived decrease in bank risk stems primarily from the use of credit growth limits, reserve requirements, and dynamic provisioning. By contrast, a pre-crisis build-up of capital surcharges on systemically important financial institutions seems to lower bank stock returns. Alternative bank risk indicators suggest that the latter is likely to be driven by concerns about profits rather than the probability of default.

15.
Biotechnol Appl Biochem ; 70(2): 811-823, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36070882

ABSTRACT

During the past few years, advances in drag delivery have provided many opportunities in the treatment of various diseases and cancer. Arsenic trioxide (ATO) and Erlotinib (Erlo) are two drugs, approved by the United States Food and Drug Administration to treat cancer, but their use is limited in terms of the toxicity of ATO and the low solubility of Erlo. This study aimed to prepare arginine-glycine-aspartic acid (RGD)-decorated nanoliposomes (NLPs) containing Erlo and ATO (NLPs-ATO-Erlo-RGD) to increase the solubility and reduce the toxicity of Erlo and ATO for cancer treatment. The results of transmission electron microscopy and dynamic light scattering showed that NLPs were synthesized uniformly, with spherical shape morphology and particle sizes between 140 and 160 nm. High-performance liquid chromatography and ICP-MS results showed that about 90% of the drug was loaded in the NLPs. In comparison with NLPs-ATO-Erlo, NLPs-ATO-Erlo-RGD demonstrated considerable toxicity against the αvß3 overexpressing PC3 cell line in the MTT experiment. It had no effect on the PANC-1 cell line. In addition, apoptosis assays using Annexin V/PI demonstrated that NLPs-ATO-Erlo-RGD generated the highest apoptotic rates in PC3 cells when compared with NLPs-ATO-Erlo and the combination of free ATO and Erlo. Furthermore, treatment with NLPs-ATO-Erlo-RGD in (p < 0.05) PC3 cell line significantly reduced EGFR level. It is concluded NLPs-ATO-Erlo-RGD as a novel drug delivery system may be a promising platform for the treatment of cancer.


Subject(s)
Antineoplastic Agents , Arsenicals , Humans , Arsenic Trioxide/pharmacology , Erlotinib Hydrochloride/pharmacology , PC-3 Cells , Oxides/pharmacology , Arsenicals/pharmacology , Arsenicals/chemistry , Arsenicals/therapeutic use , Cell Line, Tumor , Apoptosis , Oligopeptides/pharmacology , Oligopeptides/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry
16.
Pharmacol Rep ; 75(1): 189-198, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36334247

ABSTRACT

BACKGROUND: It has been suggested that the anti-hyperglycemic effect of metformin could be associated with its impact on long non-coding RNA (lncRNA) expression levels. Accordingly, in the current study, we evaluated the effect of metformin on the expression of H19, MEG3, MALAT1, and GAS5 in in vitro and in vivo situations. METHODS: The effect of hyperglycemia and metformin treatment on the lncRNAs expression level was evaluated in HepG2 cells. A total of 179 age- and sex-matched subjects, including 88 newly diagnosed patients with type 2 diabetes (T2D) and 91 healthy volunteers, were included in the case-control phase of the study. Moreover, 40 newly diagnosed patients participated in the study's open-labeled non-controlled clinical trial phase. The expression levels of lncRNA in HepG2 cells and whole blood samples were determined using QRT-PCR. RESULTS: In vitro results showed that hyperglycemia induced H19 and MALAT1 and decreased GAS5 expression levels. Moreover, metformin decreased H19 and increased GAS5 expression in high glucose-treated cells. Case-control study findings revealed that the circulating levels of H19, MALAT1, and MEG3 were significantly elevated in T2D patients compared to the control subjects. Finally, results showed that the level of circulating H19 levels decreased while GAS5 increased in T2D patients after taking metformin for 2 months. CONCLUSION: The results of the current study provided evidence that metformin could exert its effect in the treatment of T2D by altering the expression levels of H19 and GAS5.


Subject(s)
Diabetes Mellitus, Type 2 , Metformin , RNA, Long Noncoding , Humans , Metformin/pharmacology , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/genetics , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Case-Control Studies
17.
EXCLI J ; 22: 1235-1263, 2023.
Article in English | MEDLINE | ID: mdl-38234970

ABSTRACT

Hesperidin and hesperetin, two flavonoids with potential therapeutic value, have been extensively studied in the context of diabetes management. The main objective of this research is to ascertain their potential as therapeutic options for managing diabetes and its complications. The present study utilized a systematic review methodology and comprehensively explored relevant literature from databases, including PubMed, Scopus, and Web of Science, from inception until July 2023. The review summarized the outcomes related to the molecular, cellular, and metabolic effects of hesperidin and hesperetin in diabetes and its complications. Hesperetin exhibits a potential treatment for preventing diabetes and its associated complications through modulation of inflammatory cytokine release and expression via the pathway of signaling through Toll-like receptor/Myeloid differentiation factor 88/Nuclear factor-kappa B. Hesperidin shows promise as a biomolecule for treating diabetic neuropathy, primarily through activation of nuclear factor erythroid 2-related factor 2 (Nrf-2), as an antioxidant-response element signaling, leading to neuroprotective effects. Both compounds demonstrated the ability to normalize blood glucose levels and reduce serum and liver lipid levels, making them potential candidates for managing hypoglycemia and hypolipidemia in diabetes. Hesperidin also showed potential benefits against diabetic nephropathy by suppressing transforming growth factor-ß1-integrin-linked kinase-Akt signaling and enhancing renal function. Furthermore, hesperidin's antioxidant, anti-inflammatory, and anti-depressant effects in diabetic conditions expanded its potential therapeutic applications. This systematic review provides substantial evidence supporting the consideration of hesperidin and hesperetin for diabetes and its complications. It offers exciting possibilities for developing novel, cost-effective treatment options to enhance diabetes management and patient outcomes.

18.
Pathol Res Pract ; 237: 154010, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35843034

ABSTRACT

Cancer stem cells (CSCs) as a small subpopulation in tumor bulk are believed to initiate tumor formation and are responsible for the resistance to cancer therapy. The proliferation and differentiation of CSCs result in heterogeneity in a tumor which increases the chance of tumor survival and invasion. Many signaling pathways are abnormally activated or repressed in CSCs. Understanding these pathways and the metabolisms in CSCs may help targeted therapy in drug-resistant tumors. The PI3K/Akt/mTOR pathway is one of the major signaling pathways in CSCs involved in the maintenance of stemness, proliferation, differentiation, epithelial to mesenchymal transition (EMT), migration, and autophagy. Thus, suppressing the PI3K/Akt/mTOR pathway with inhibitors might be a promising strategy for targeted cancer therapy. Although the pathway is well-recognized and reviewed in tumor bulks, the functions in CSCs have not been well focused. Here, we reviewed the PI3K/Akt/mTOR signaling pathway and its functions in CSCs and addressed the potential therapeutic applications in drug-resistant tumors.


Subject(s)
Neoplasms , Phosphatidylinositol 3-Kinases , Humans , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Epithelial-Mesenchymal Transition , TOR Serine-Threonine Kinases/metabolism , Neoplastic Stem Cells/pathology , Signal Transduction , Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation
19.
Sensors (Basel) ; 22(12)2022 Jun 09.
Article in English | MEDLINE | ID: mdl-35746151

ABSTRACT

Quantum dots (QDs) are used progressively in sensing areas because of their special electrical properties due to their extremely small size. This paper discusses the gas sensing features of QD-based resistive sensors. Different types of pristine, doped, composite, and noble metal decorated QDs are discussed. In particular, the review focus primarily on the sensing mechanisms suggested for these gas sensors. QDs show a high sensing performance at generally low temperatures owing to their extremely small sizes, making them promising materials for the realization of reliable and high-output gas-sensing devices.

20.
Mol Biol Rep ; 49(5): 3559-3567, 2022 May.
Article in English | MEDLINE | ID: mdl-35553331

ABSTRACT

BACKGROUND: Coronary artery disease (CAD) is considered to be one of the most pivotal causes of death in the world. Over the past two decades, significant changes occurred in the diagnosis, prognosis, and treatment of CAD, which has helped reduce mortality rates. microRNAs (miRs) are a class of more than 5000 non-encoding RNA molecules (21-25 nucleotides across the length) that regulate complex biological processes. Today, miRNAs are used to study cardiovascular diseases. In the present study, the expression of miR-146a،miR-27, miR-149, and miR-34a in plasma suffering from CAD and the control group were investigated. METHODS AND RESULTS: The present research was performed on 30 men with CAD and 30 healthy men as controls. The expression levels of miR-146a, miR-27a, miR-149, and miR-34a in the plasma of patients with CAD and the control group were measured using real-time PCR. Also, the correlation between the expression of circulating miRs levels and biochemical LDL-C, HDL-C, BMI, and total cholesterol was evaluated. The expression of miR-27a in the plasma of the CAD group was higher than in the control group (p = 0.020). The expression of miR-146a was downregulated in CAD patients compared to normal subjects (p = 0. 026). However, the expression of miR-34a, miR-149 in the plasma of CAD patients was not significantly different with the control group. In addition to, a direct correlation was found between the expression of miR-146a and HDL-c, the expression of miR-27a and LDL-C and the expression of miR-34a and total cholesterol. Also, the negative correlation between expressions of miR-149 with BMI was reported. CONCLUSION: The obtained results demonstrated that miRs were closely related to biochemical factors and it points out the fact that miRNAs can be applied as a potential strategy for diagnosis and treatment of CAD.


Subject(s)
Circulating MicroRNA , Coronary Artery Disease , MicroRNAs , Cholesterol, LDL , Circulating MicroRNA/genetics , Coronary Artery Disease/metabolism , Humans , Male , MicroRNAs/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL