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Mutant-specific inhibitors of KRASG12C, such as AMG510 (sotorasib) and MRTX849 (adagrasib), offer the unprecedented opportunity to inhibit KRAS, the most frequently mutated and heretofore undruggable oncoprotein. While clinical data are still limited, on-target mutations in KRASG12C at position 12 and other sites are emerging as major drivers of clinical relapse. We identified additional mutations in KRASG12C that impact inhibitor sensitivity through a saturation mutagenesis screen in the KRASG12C NCI-H358 nonsmall-cell lung cancer (NSCLC) cell line. We also identified individuals in population genetic databases harboring these resistance mutations in their germline and in tumors, including a subset that co-occur with KRASG12C, indicating that these mutations may preexist in patients treated with KRASG12C inhibitors. Notably, through structural modeling, we found that one such mutation (R68L) interferes with the critical proteindrug interface, conferring resistance to both inhibitors. Finally, we uncovered a mutant (S17E) that demonstrated a strong sensitizing phenotype to both inhibitors. Functional studies suggest that S17E sensitizes KRASG12C cells to KRASG12C inhibition by impacting signaling through PI3K/AKT/mTOR but not the MAPK signaling pathway. Our studies highlight the utility of unbiased mutation profiling to understand the functional consequences of all variants of a disease-causing genetic mutant and predict acquired resistant mutations in the targeted therapeutics.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutagênese , Mutação , Piperazinas , Proteínas Proto-Oncogênicas p21(ras)/genética , Piridinas , PirimidinasRESUMO
BACKGROUND: Dentin hypersensitivity (DH) is one of the most challenging and persistent dental complaints characterized by transient, intense pain triggered by various stimuli. It affects a significant portion of the global population, predominantly those aged 20-40. This study aims to evaluate the desensitizing efficacy of seventh-generation dentin bonding agents (Single Bond Universal by 3 M ESPE and Xeno-V + by Dentsply) against a control group using Bifluorid 12 by Voco in mitigating DH within a month of the follow-up period. METHODS: This was a single-center, parallel-group, double-blind, controlled randomized clinical trial conducted at Dow University of Health Sciences, Karachi, Pakistan. A total of 105 patients with DH were allocated into three groups for this study. The patients were divided into three groups (Single Bond Universal by 3 M ESPE and Xeno-V + by Dentsply) and the control group containing fluoride varnish (Bifluorid 12 by Voco). Discomfort Interval Scale scores and Schiff Cold Air Sensitivity Scale scores were recorded at baseline, immediately after the intervention, after 01 weeks, and after 01 month. RESULTS: All the materials demonstrated a statistically significant reduction in discomfort and sensitivity (DIS scores p-value 0.01) immediately after 01 week and over a period of 01 month after treatment compared with the baseline scores before application, with no single material proving superior over the one-month observation period. The study also provided insights into dental hygiene practices, with a significant majority using a toothbrush and sensitivity patterns, with cold stimuli being the most common cause of sensitivity. CONCLUSION: The study demonstrates that Single Bond Universal, Xeno V+, and Bifluorid 12 are equally effective in reducing dentin hypersensitivity, with no distinct superiority observed over a one-month period. The findings highlight the potential of fluoride varnishes as a less technique-sensitive and cost-effective option for treating DH, offering valuable insights for future research and clinical practice. TRIAL REGISTRATION: NCT04225247 ( https://clinicaltrials.gov/study/NCT04225247 ), Date of Registration: 13/01/2020. (Retrospectively registered).
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Dessensibilizantes Dentinários , Sensibilidade da Dentina , Adesivos Dentinários , Fluoretos Tópicos , Humanos , Sensibilidade da Dentina/tratamento farmacológico , Feminino , Método Duplo-Cego , Masculino , Adulto , Dessensibilizantes Dentinários/uso terapêutico , Adesivos Dentinários/uso terapêutico , Fluoretos Tópicos/uso terapêutico , Fluoretos/uso terapêutico , Adulto Jovem , Bis-Fenol A-Glicidil Metacrilato/uso terapêutico , Resultado do Tratamento , Cimentos de Resina/uso terapêutico , Medição da DorRESUMO
Water pollution due to organic waste and various microorganisms cause severe health problems. Numbers of techniques are used to eliminate organic waste and microorganisms from water because water pollution is a substantial issue in the current era. In the present study, sustainable and effective CuO/SnO2@g-C3N4 nanocomposites were prepared via green and chemical approach. The photo degradation of ciprofloxacin (CIP) and methylene blue (MB) by the green synthesized nanocomposite were tested. Visible and dark conditions both were used to conduct this test. The results showed that the nanocomposite is much more effective in light than in dark conditions. The synthesized nanocomposite was also tested both in light and dark against highly drug resistant microorganisms' Bacillus subtilis (B.subtilis) and Escherichia coli (E.coli). As a result, the antibacterial evaluation revealed substantial antibacterial activity in the presence of light, with a zone of inhibition covering an area of 19 (±0.5) mm and 20 (±0.1) mm, respectively, against gram negative and gram positive bacteria such as E. coli and B. subtilis. The results showed that the CuO/SnO2@g-C3N4 nanocomposite is a stable, eco-friendly photocatalyst with significant resistance to CIP and MB degradation and a substantial inhibitory effect towards microorganisms in visible light.
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Ciprofloxacina , Nanocompostos , Ciprofloxacina/farmacologia , Azul de Metileno/farmacologia , Azul de Metileno/química , Espécies Reativas de Oxigênio , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias , Nanocompostos/química , CatáliseRESUMO
PD-1 and PD-L1 act to restrict T cell responses in cancer and contribute to self-tolerance. Consistent with this role, PD-1 checkpoint inhibitors have been associated with immune-related adverse events (irAEs), immune toxicities thought to be autoimmune in origin. Analyses of dermatological irAEs have identified an association with improved overall survival (OS) following anti-PD-(L)1 therapy, but the factors that contribute to this relationship are poorly understood. We collected germline whole-genome sequencing data from IMvigor211, a recent phase 3 randomized controlled trial comparing atezolizumab (anti-PD-L1) monotherapy to chemotherapy in bladder cancer. We found that high vitiligo, high psoriasis, and low atopic dermatitis polygenic risk scores (PRSs) were associated with longer OS under anti-PD-L1 monotherapy as compared to chemotherapy, reflecting the Th17 polarization of these diseases. PRSs were not correlated with tumor mutation burden, PD-L1 immunohistochemistry, nor T-effector gene signatures. Shared genetic factors impact risk for dermatological autoimmunity and anti-PD-L1 monotherapy in bladder cancer.
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Pele/imunologia , Neoplasias da Bexiga Urinária/imunologia , Anticorpos Monoclonais Humanizados/administração & dosagem , Autoimunidade , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Estudos de Coortes , Humanos , Herança Multifatorial , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Pele/efeitos dos fármacos , Células Th17/imunologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genéticaRESUMO
The use of Advance Oxidation Process (AOPs) has been extensively examined in order to eradicate organic pollutants. This review assesses the efficacy of photolysis, O3 based (O3/UV, O3/H2O2, O3/H2O2/UV, H2O2/UV, Fenton, Fenton-like, hetero-system) and sonochemical and electro-oxidative AOPs in this regard. The main purpose of this review and some suggestions for the advancement of AOPs is to facilitate the elimination of toxic organic pollutants. Initially proposed for the purification of drinking water in 1980, AOPs have since been employed for various wastewater treatments. AOPs technologies are essentially a process intensification through the use of hybrid methods for wastewater treatment, which generate large amounts of hydroxyl (â¢OH) and sulfate (SO4·-) radicals, the ultimate oxidants for the remediation of organic pollutants. This review covers the use of AOPs and ozone or UV treatment in combination to create a powerful method of wastewater treatment. This novel approach has been demonstrated to be highly effective, with the acceleration of the oxidation process through Fenton reaction and photocatalytic oxidation technologies. It is clear that Advance Oxidation Process are a helpful for the degradation of organic toxic compounds. Additionally, other processes such as â¢OH and SO4·- radical-based oxidation may also arise during AOPs treatment and contribute to the reduction of target organic pollutants. This review summarizes the current development of AOPs treatment of wastewater organic pollutants.
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Poluentes Ambientais , Radical Hidroxila , Peróxido de Hidrogênio , Águas Residuárias , OxirreduçãoRESUMO
The current paper explains how to make mesoporous silica microparticles (MSM) by mixing water and dichloromethane. Several dichloromethane-water ratios were used to adjust the reaction mixture for the first time to easily synthesize mesoporous silica micro particles with regulated particle size. By carefully modifying the concentrations of water and dichloromethane, a higher level of consistency was achieved in the production of micro particles, i.e. to a 2:1 v/v ratio. It was discovered that variations in the dichloromethane-to-water ratios significantly affect the surface roughness and morphologies of mesoporous silica particles along with size. This is most likely because the solvent affects how quickly tetraethyl orthosilicate (TEOS) and how quickly inorganic species polymerize. In all experiments, conditions were maintained the same at 25oC temperature and 1000 rpm. Scanner electron microscopy (SEM), Fourier transform infrared (FTIR) and X-ray powder diffraction (XRD) methods were used to identify the structure of MSM. The in vitro cytotoxicity assays showed that the produced particles, which had a diameter of 1.0 m, were safe for usage in the cellular system.
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Cloreto de Metileno , Projetos de Pesquisa , Tamanho da Partícula , Dióxido de Silício/toxicidade , ÁguaRESUMO
The study aimed to prepare and characterize biodegradable sustained-release beads of letrozole (LTZ) for treating cancerous disease. The ionotropic gelation method was used for the preparation and calcium chloride (CaCl2) was used as a gelating agent, while chitosan (CTS) and sodium alginate (NaAlg) as biodegradable polymeric matrices in the blend hydrogel beads. The beads were characterized for their size, surface morphology, drug entrapment efficiency, drug-polymer interaction and crystallinity using different analytic techniques, including optical microscopy, Scanning Electron Microscopy (SEM), UV-spectroscopy, Fourier-transform Infrared Spectroscopy (FTIR), Thermo gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) and X-ray Diffraction Analysis (XRD) respectively. In vitro swelling studies were also applied to observe the response of these polymeric networks against different pH (at 1.2, 6.8 and 7.4 pH). The results from TGA and DSC exhibited that the components in the formulation possess better thermal stability. The XRD of polymeric networks displays a minor crystalline and significant amorphous nature. The SEM micrographs revealed that polymeric networks have uneven surfaces and grooves. Better swelling and in vitro outcomes were achieved at a high pH (6.8,7.4), which endorsed the pH-responsive characteristics of the prepared beads. Hence, beads based on chitosan and sodium alginate were successfully synthesized and can be used for the controlled release of letrozole.
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Quitosana , Preparações de Ação Retardada , Letrozol , Quitosana/química , Tamanho da Partícula , Polímeros , Alginatos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Ácidos Hexurônicos/química , Microscopia Eletrônica de Varredura , Ácido Glucurônico/químicaRESUMO
RATIONALE: Excessive Ang II (angiotensin II) levels lead to a profibrotic and hypertrophic milieu that produces deleterious remodeling and dysfunction in hypertension-associated heart failure. Agents that disrupt Ang II-induced cardiac dysfunction may have clinical utility in the treatment of hypertension-associated heart failure. OBJECTIVE: We have examined the potential effect of celastrol-a bioactive compound derived from the Celastraceae family-on Ang II-induced cardiac dysfunction. METHODS AND RESULTS: In rat primary cardiomyocytes and H9C2 (rat cardiomyocyte-like H9C2) cells, celastrol attenuates Ang II-induced cellular hypertrophy and fibrotic responses. Proteome microarrays, surface plasmon resonance, competitive binding assays, and molecular simulation were used to identify the molecular target of celastrol. Our data showed that celastrol directly binds to and inhibits STAT (signal transducer and activator of transcription)-3 phosphorylation and nuclear translocation. Functional tests demonstrated that the protection of celastrol is afforded through targeting STAT3. Overexpression of STAT3 dampens the effect of celastrol by partially rescuing STAT3 activity. Finally, we investigated the in vivo effect of celastrol treatment in mice challenged with Ang II and in the transverse aortic constriction model. We show that celastrol administration protected heart function in Ang II-challenged and transverse aortic constriction-challenged mice by inhibiting cardiac fibrosis and hypertrophy. CONCLUSIONS: Our studies show that celastrol inhibits Ang II-induced cardiac dysfunction by inhibiting STAT3 activity.
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Angiotensina II/toxicidade , Sistemas de Liberação de Medicamentos/métodos , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Triterpenos/administração & dosagem , Remodelação Ventricular/efeitos dos fármacos , Animais , Linhagem Celular , Células HEK293 , Humanos , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Triterpenos Pentacíclicos , Estrutura Terciária de Proteína , Distribuição Aleatória , Ratos , Fator de Transcrição STAT3/química , Tripterygium , Triterpenos/química , Remodelação Ventricular/fisiologiaRESUMO
This study was designed to evaluate the emulsifying and rheological properties of acorn protein isolate (API) in different pH mediums (pH 3, 7 and 9) and in the presence of ionic salts (1 M NaCl and 1 M CaCl2). API shows higher solubility in distilled water at pH 7, while at the same pH, a decrease in solubility was observed for API in the presence of CaCl2 (61.30%). A lower emulsifying activity index (EAI), lower stability index (ESI), larger droplet sizes and slight flocculation were observed for API in the presence of salts at different pHs. Importantly, CaCl2 treated samples showed relevantly higher EAI (252.67 m2/g) and ESI (152.67 min) values at all pH as compared to NaCl (221.76 m2/g), (111.82 min), respectively. A significant increase in interfacial protein concentration (4.61 mg/m2) was observed for emulsion at pH 9 with CaCl2, while the major fractions of API were observed in an interfacial layer after SDS-PAGE analysis. All of the emulsion shows shear thinning behavior (τc > 0 and n < 1), while the highest viscosity was observed for emulsion prepared with CaCl2 at pH 3 (11.03 ± 1.62). In conclusion, API, in the presence of ionic salts at acidic, neutral and basic pH, can produce natural emulsions, which could be substitutes for synthetic surfactants for such formulations.
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Quercus , Sais , Cloreto de Cálcio , Emulsificantes/química , Emulsões/química , Concentração de Íons de Hidrogênio , Proteínas , Reologia , Cloreto de SódioRESUMO
Cancer immunotherapy has emerged as an effective therapy in a variety of cancers. However, a key challenge in the field is that only a subset of patients who receive immunotherapy exhibit durable response. It has been hypothesized that host genetics influences the inherent immune profiles of patients and may underlie their differential response to immunotherapy. Herein, we systematically determined the association of common germline genetic variants with gene expression and immune cell infiltration of the tumor. We identified 64,094 expression quantitative trait loci (eQTLs) that associated with 18,210 genes (eGenes) across 24 human cancers. Overall, eGenes were enriched for their being involved in immune processes, suggesting that expression of immune genes can be shaped by hereditary genetic variants. We identified the endoplasmic reticulum aminopeptidase 2 (ERAP2) gene as a pan-cancer type eGene whose expression levels stratified overall survival in a subset of patients with bladder cancer receiving anti-PD-L1 (atezolizumab) therapy. Finally, we identified 103 gene signature QTLs (gsQTLs) that were associated with predicted immune cell abundance within the tumor microenvironment. Our findings highlight the impact of germline SNPs on cancer-immune phenotypes and response to therapy; and these analyses provide a resource for integration of germline genetics as a component of personalized cancer immunotherapy.
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Genes Neoplásicos , Neoplasias/genética , Neoplasias/imunologia , Polimorfismo Genético , Aminopeptidases/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Mutação em Linhagem Germinativa , Humanos , Imunidade Celular/genética , Imunoterapia , Ligante Coestimulador de Linfócitos T Induzíveis/genética , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Masculino , Neoplasias/terapia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/terapiaRESUMO
Printed electronics implies the use of low-cost, scalable, printing technologies to fabricate electronic devices and circuits on flexible substrates, such as paper or plastics. The development of this new electronic is currently expanding because of the emergence of the internet-of-everything. Although lot of attention has been paid to functional inks based on organic semiconductors, another class of inks is based on nanoparticles obtained from exfoliated 2D materials, such as graphene and metal sulfides. The ultimate scientific and technological challenge is to find a strategy where the exfoliated nanoparticle flakes in the inks can, after solvent evaporation, form a solid which displays performances equal to the single crystal of the 2D material. In this context, a printed layer, formed from an ink composed of nano-flakes of TiS2 intercalated with hexylamine, which displays thermoelectric properties superior to organic intercalated TiS2 single crystals, is demonstrated for the first time. The choice of the fraction of exfoliated nano-flakes appears to be a key to the forming of a new self-organized layered material by solvent evaporation. The printed layer is an efficient n-type thermoelectric material which complements the p-type printable organic semiconductors The thermoelectric power factor of the printed TiS2/hexylamine thin films reach record values of 1460 µW m-1 K-2 at 430 K, this is considerably higher than the high value of 900 µW m-1 K-2 at 300 K reported for a single crystal. A printed thermoelectric generator based on eight legs of TiS2 confirms the high-power factor values by generating a power density of 16.0 W m-2 at ΔT = 40 K.
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Water is a key component for living beings to sustain life and for socio-economic development. Anthropogenic activities contribute significantly to ground/surface water contamination particularly with trace elements. The present study was designed to evaluate distribution and health risk assessment of trace elements in ground/surface water of the previously unexplored area, Tehsil Kot Addu, Southern-Punjab, Pakistan. Ground/surface water samples (n = 120) were collected from rural and urban areas of Kot Addu. The samples were analyzed for physicochemical characteristics: total dissolved solids (TDS), pH, and EC (electrical conductivity), cations, anions, and trace elements particularly arsenic (As), lead (Pb), cadmium (Cd), and zinc (Zn). All of the water characteristics were evaluated based on the water quality standards set by World Health Organization (WHO). Results revealed the suitability of water for drinking purpose with respect to physicochemical attributes. However, the alarming levels of trace elements especially As, Cd, and Pb make it unfit for drinking purpose. Noticeably, 23, 96, and 98% of water samples showed As, Cd, and Pb concentrations higher than the permissible limits. Overall, the estimated carcinogenic and non-carcinogenic risk to the exposed community was higher than the safety level of USEPA, suggesting the probability of cancer and other diseases through long-term exposure via ingestion routes. Therefore, this study demonstrated an urgent need for water filtration/purification techniques, and some quality control measures are warranted to protect the health of the exposed community in Tehsil Kot Addu.
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Água Potável , Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Água Potável/análise , Monitoramento Ambiental , Metais Pesados/análise , Análise Multivariada , Paquistão , Medição de Risco , Poluentes Químicos da Água/análiseRESUMO
BACKGROUND: Cigarette smoke is associated with higher oral Candida carriage and possible predisposition and increased susceptibility to oral candidal infection. Candida dubliniensis is associated with oral candidosis. Candidal adherence to buccal epithelial cells (BEC) and denture acrylic surfaces (DAS), germ tube (GT) formation, cell surface hydrophobicity (CSH) and hemolysin production are pathogenic traits of Candida. OBJECTIVES: The impact of exposure to cigarette smoke on the aforementioned pathogenic attributes of oral C. dubliniensis has not been studied. Hence, the impact of cigarette smoke condensate (CSC) on adhesion to BEC and DAS, GT formation, CSH and hemolysin production of 20 oral C. dubliniensis isolates after exposure to CSC for 24, 48 and 72 h was ascertained. METHODS: After preparation of the CSC, using an in-house smoking device, the Candida isolates were exposed to the CSC for 24, 48 and 72 h, by a previously described in vitro method. Thereafter, the adhesion to BEC and DAS, GT formation, CSH and hemolysin production of C. dubliniensis isolates was investigated by hitherto described in vitro assays. RESULTS: Exposure to CSC significantly increased the ability of C. dubliniensis oral isolates to adhere to BEC, DAS, GT formation, CSH and produce hemolysin following 24-h, 48-h and 72-h exposure periods to CSC (P < 0.001 for all attributes tested). CONCLUSIONS: Exposure of oral C. dubliniensis isolates to CSC may significantly promote in vitro adhesion traits and hemolysin production of these isolates, thereby augmenting its pathogenicity in vitro in the presence of cigarette smoke.
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Candida , Candidíase Bucal , Adesão Celular/efeitos dos fármacos , Proteínas Hemolisinas/metabolismo , Fumaça/efeitos adversos , Candida/efeitos dos fármacos , Candida/metabolismo , Candida/patogenicidade , Fumar Cigarros/efeitos adversos , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Proteínas Fúngicas/efeitos dos fármacos , Proteínas Fúngicas/metabolismo , Proteínas Hemolisinas/efeitos dos fármacos , Humanos , Boca/microbiologia , Boca/patologia , Mucosa Bucal/microbiologia , Mucosa Bucal/patologiaRESUMO
In this paper, we present an evaluation of four encoder-decoder CNNs in the segmentation of the prostate gland in T2W magnetic resonance imaging (MRI) image. The four selected CNNs are FCN, SegNet, U-Net, and DeepLabV3+, which was originally proposed for the segmentation of road scene, biomedical, and natural images. Segmentation of prostate in T2W MRI images is an important step in the automatic diagnosis of prostate cancer to enable better lesion detection and staging of prostate cancer. Therefore, many research efforts have been conducted to improve the segmentation of the prostate gland in MRI images. The main challenges of prostate gland segmentation are blurry prostate boundary and variability in prostate anatomical structure. In this work, we investigated the performance of encoder-decoder CNNs for segmentation of prostate gland in T2W MRI. Image pre-processing techniques including image resizing, center-cropping and intensity normalization are applied to address the issues of inter-patient and inter-scanner variability as well as the issue of dominating background pixels over prostate pixels. In addition, to enrich the network with more data, to increase data variation, and to improve its accuracy, patch extraction and data augmentation are applied prior to training the networks. Furthermore, class weight balancing is used to avoid having biased networks since the number of background pixels is much higher than the prostate pixels. The class imbalance problem is solved by utilizing weighted cross-entropy loss function during the training of the CNN model. The performance of the CNNs is evaluated in terms of the Dice similarity coefficient (DSC) and our experimental results show that patch-wise DeepLabV3+ gives the best performance with DSC equal to 92 . 8 % . This value is the highest DSC score compared to the FCN, SegNet, and U-Net that also competed the recently published state-of-the-art method of prostate segmentation.
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Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Próstata/diagnóstico por imagem , Humanos , Masculino , SemânticaRESUMO
The present study is the first attempt to evaluate the potential of acid and base activated biochar derived from cotton stalks (CSB) for the removal of As from contaminated water. The CSB was treated with 0.5 M KOH (BCSB) and H3PO4 (ACSB) separately to change its surface properties. The CSB, ACSB and BSCB were characterized using BET, FTIR, and SEM analysis to check the effectiveness and insight of the main mechanisms involved in the removal of As. A series of batch experiments was performed using As-contaminated synthetic water and groundwater samples. The effects of initial concentration of As, contact time, dose of the biochars, solution pH, type of the biochar and coexisting ions on the removal of As were investigated. Results revealed that BCSB efficiently removed As (90-99.5%) from contaminated water as compared with ACSB (84-98%) and CSB (81-98%) due to improved surface properties when As concentration was varied from 0.1 to 4.0 mg/L. The experimental data were best fitted with Freundlich adsorption isotherm as compared with Langmuir, Temkin and Dubinin-Radushkevich models. However, kinetic data were well explained with pseudo-second-order kinetic model rather than pseudo-first-order, intra-particle diffusion and Elovich models. The sorption energy indicated that physical adsorption was involved in the removal of As. The comparison of adsorption results with other biochars and their modified forms suggests that activation of CSB with base can be used effectively (4.48 mg/g) as a low-cost adsorbent for maximum removal of As from contaminated aqueous systems.
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Arsênio/isolamento & purificação , Carvão Vegetal/química , Gossypium/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Difusão , Água Subterrânea/química , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Caules de Planta/química , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Purificação da Água/métodosRESUMO
A comparison between a graphene suspended double-layer modulator and a subwavelength-thickness modulator is presented. The physics of both are analyzed in detail and show a confined mode in the suspended modulator but a leaky mode in the subwavelength modulator. The leaky mode shows zero light-matter interaction and zero modulation depth, which should be avoided in designing a modulator. The suspended modulator can achieve much lower insertion loss and an extraordinarily higher figure of merit (â¼2480) than the subwavelength modulator. Both operate with high modulation efficiency and comparable modulation speeds. We believe these designs will pave the way to realizing high-efficiency, near-fundamental-limit graphene modulators.
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The present study aims at evaluating a batch scale biosorption potential of Moringa oleifera leaves (MOL) for the removal of Pb(II) from aqueous solutions. The MOL biomass was characterized by FTIR, SEM, EDX, and BET. The impact of initial concentrations of Pb (II), adsorbent dosage, pH, contact time, coexisting inorganic ions (Ca2+, Na+, K+, Mg2+, CO32-, HCO3-, Cl-), electrical conductivity (EC) and total dissolved salts (TDS) in water was investigated. The results revealed that maximum biosorption (45.83 mg/g) was achieved with adsorbent dosage 0.15 g/100 mL while highest removal (98.6%) was obtained at adsorbent biomass 1.0 g/100 mL and pH 6. The presence of coexisting inorganic ions in water showed a decline in Pb(II) removal (8.5% and 5%) depending on the concentrations of ions. The removal of Pb(II) by MOL decreased from 97% to 89% after five biosorption/desorption cycles with 0.3 M HCl solution. Freundlich model yielded a better fit for equilibrium data and the pseudo-second-order well described the kinetics of Pb(II) biosorption. FTIR spectra showed that -OH, C-H, -C-O, -C = O, and -O-C functional groups were involved in the biosorption of Pb(II). The change in Gibbs free energy (ΔG = -28.10 kJ/mol) revealed that the biosorption process was favorable and thermodynamically driven. The results suggest MOL as a low cost, environment-friendly alternative biosorbent for the remediation of Pb(II) contaminated water.
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Moringa oleifera , Poluentes Químicos da Água , Adsorção , Biodegradação Ambiental , Biomassa , Concentração de Íons de Hidrogênio , Cinética , ChumboRESUMO
During tissue morphogenesis, simple epithelial sheets undergo folding to form complex structures. The prevailing model underlying epithelial folding involves cell shape changes driven by myosin-dependent apical constriction. Here we describe an alternative mechanism that requires differential positioning of adherens junctions controlled by modulation of epithelial apical-basal polarity. Using live embryo imaging, we show that before the initiation of dorsal transverse folds during Drosophila gastrulation, adherens junctions shift basally in the initiating cells, but maintain their original subapical positioning in the neighbouring cells. Junctional positioning in the dorsal epithelium depends on the polarity proteins Bazooka and Par-1. In particular, the basal shift that occurs in the initiating cells is associated with a progressive decrease in Par-1 levels. We show that uniform reduction of the activity of Bazooka or Par-1 results in uniform apical or lateral positioning of junctions and in each case dorsal fold initiation is abolished. In addition, an increase in the Bazooka/Par-1 ratio causes formation of ectopic dorsal folds. The basal shift of junctions not only alters the apical shape of the initiating cells, but also forces the lateral membrane of the adjacent cells to bend towards the initiating cells, thereby facilitating tissue deformation. Our data thus establish a direct link between modification of epithelial polarity and initiation of epithelial folding.
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Junções Aderentes/fisiologia , Polaridade Celular , Drosophila melanogaster/citologia , Drosophila melanogaster/embriologia , Células Epiteliais/citologia , Epitélio/embriologia , Gastrulação/fisiologia , Junções Aderentes/ultraestrutura , Animais , Forma Celular , Coristoma , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Epitélio/metabolismo , Epitélio/ultraestrutura , Gástrula/citologia , Gástrula/embriologia , Gástrula/metabolismo , Gástrula/ultraestrutura , Quinase 3 da Glicogênio Sintase , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismoRESUMO
A simple and controlled strategy has been used to synthesise Mn3O4 nanoparticles (NPs) via hydrothermal method. The Mn3O4 nanoparticles were further applied for supercapacitor electrode materials. The unique squared-shape Mn3O4 nanoparticles exhibited excellent electrochemical performance due to the small size and porous architecture. After electrochemical testing, the Mn3O4 NPs based electrode showed a large specific capacitance (380 F g-1, 1.0 mAcm-2) and good cycling stability (88.6%) of the initial capacitance after 5000 cycles in 1.0 M Na2SO4 solution. These results may provide useful guidelines for materials selection, synthesis, size and configuration designs for the novel energy storage devices based on transitional metal oxides.
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Candida fungus ball is a rare presentation of urinary tract infections among adult patients and is associated with considerable morbidity. Because clinical signs are not specific, diagnosis is often delayed. Furthermore, treatment is occasionally difficult, and the approach to such cases varies widely among different centers. In this report, we describe a patient with retroperitoneal fibrosis who developed a renal fungus ball. Management of this challenging case is discussed, and review of the literature is presented.