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1.
J Contam Hydrol ; 265: 104380, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38875891

RESUMEN

Due to rapid urbanization, there have been continuous environmental threats from different pollutants, especially from microplastics. Plastic products rapidly proliferate significantly contributing to the occurrence of micro-plastics, which poses a significant environmental risk. These microplastics originated from diverse sources and are characterized by their persistent and widespread occurrence; human health and the entire ecosystem are adversely affected by them. The removal of microplastics not only requires innovative technologies but also efficient materials capable of effectively eliminating them from our environment. The progress made so far has highlighted the advantages of utilizing the dimensional and structural properties of nanomaterials to increase the effectiveness of existing methods for micro-plastic treatment, aiming for a more sustainable approach to their removal. In the current review, we demonstrate a thorough overview of the sources, occurrences, and potential harmful effects of microplastics, followed by a further discussion of promising technologies used for their removal. An in-depth examination of both advantages and a few limitations of all these given technologies, including physical, chemical, and biological approaches, has been discussed. Additionally, the review explores the use of nanomaterials as an effective means to overcome obstacles and improve the efficiency of microplastic elimination methods. n conclusion, this review addresses, current challenges in this field and outlines the future perspectives for further research in this domain.

2.
Small ; : e2402015, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597684

RESUMEN

Water electrolysis is among the recent alternatives for generating clean fuels (hydrogen). It is an efficient way to produce pure hydrogen at a rapid pace with no unwanted by-products. Effective and cheap water-splitting electrocatalysts with enhanced activity, specificity, and stability are currently widely studied. In this regard, noble metal-free transition metal-based catalysts are of high interest. Iron sulfide (FeS) is one of the essential electrocatalysts for water splitting because of its unique structural and electrochemical features. This article discusses the significance of FeS and its nanocomposites as efficient electrocatalysts for oxygen evolution reaction (OER), hydrogen evolution reaction (HER), oxygen reduction reaction (ORR), and overall water splitting. FeS and its nanocomposites have been studied also for energy storage in the form of electrode materials in supercapacitors and lithium- (LIBs) and sodium-ion batteries (SIBs). The structural and electrochemical characteristics of FeS and its nanocomposites, as well as the synthesis processes, are discussed in this work. This discussion correlates these features with the requirements for electrocatalysts in overall water splitting and its associated reactions. As a result, this study provides a road map for researchers seeking economically viable, environmentally friendly, and efficient electrochemical materials in the fields of green energy production and storage.

3.
J Helminthol ; 97: e75, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37846203

RESUMEN

An associated microbiome of any host helps it in different metabolic processes ranging from the decomposition of food to the maturation of gametes. Organisms with a parasitic mode of life, though present at nutritious sites inside their host, maintain their own microbiome. Nevertheless, the comprehensive characterization and functionality of microbiome in parasitic organisms remain understudied. We selected two nematode parasites of Kashmir Merino sheep viz;Haemonchus contortus and Trichuris ovis based on their higher prevalence, difference in mode of nutrition, habitation site and effect on host. The objective of the study was to explore the bacteria associated with these parasitic nematodes of sheep. We adopted a 16S rRNA metagenomic sequencing approach to estimate and compare the bacterial communities present in these two nematode species. Nematode parasites from Kashmir Merino sheep were identified morphologically and confirmed with DNA characterization. H. contortus was dominated by phylum Proteobacteria (57%), Firmicutes (25%), Bacteroidota (15%) and Actinobacteriota (3%). Conversely, T. ovis showed Proteobacteria (78%) followed by Firmicutes (8%), Bacteroidota (8%), Actinobacteriota (1%), Fusobacteriota (1%) and other phyla (4%). This study provides a comprehensive account of the microbiome composition of H. contortus and T. ovis, both of which are highly prevalent among Kashmir Merino sheep. Additionally, T. ovis exhibited a greater bacterial diversity compared to H. contortus. Notably, these nematodes were found to harbor certain pathogenic bacteria. This study can further be carried forward in gaining insights into the complex relationship between the microbiota of a parasite and its pathogenicity, reproductive potential and host microbiome modification.


Asunto(s)
Hemoncosis , Haemonchus , Nematodos , Parásitos , Enfermedades de las Ovejas , Animales , Ovinos , Haemonchus/genética , Parásitos/genética , Trichuris , ARN Ribosómico 16S/genética , Nematodos/genética , Bacterias/genética , Enfermedades de las Ovejas/parasitología , Hemoncosis/parasitología
4.
Environ Res ; 239(Pt 1): 117192, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37748672

RESUMEN

A wide array of environmental pollutants is often generated and released into the ecosystem from industrial and human activities. Antibiotics, phenolic compounds, hydroquinone, industrial dyes, and Endocrine-Disrupting Chemicals (EDCs) are prevalent pollutants in water matrices. To promote environmental sustainability and minimize the impact of these pollutants, it is essential to eliminate such contaminants. Although there are multiple methods for pollutants removal, many of them are inefficient and environmentally unfriendly. Horseradish peroxidase (HRP) has been widely explored for its ability to oxidize the aforementioned pollutants, both alone and in combination with other peroxidases, and in an immobilized way. Numerous positive attributes make HRP an excellent biocatalyst in the biodegradation of diverse environmentally hazardous pollutants. In the present review, we underlined the major advancements in the HRP for environmental research. Numerous immobilization and combinational studies have been reviewed and summarized to comprehend the degradability, fate, and biotransformation of pollutants. In addition, a possible deployment of emerging computational methodologies for improved catalysis has been highlighted, along with future outlook and concluding remarks.


Asunto(s)
Ecosistema , Contaminantes Ambientales , Humanos , Peroxidasa de Rábano Silvestre , Peroxidasas , Catálisis , Antibacterianos
5.
Environ Res ; 231(Pt 3): 116241, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37244493

RESUMEN

In this work, lanthanum ferrite nanoparticles were synthesized via a simple co-precipitation method. Two different templates, namely sorbitol and mannitol, were used in this synthesis to tune the optical, structural, morphological, and photocatalytic properties of lanthanum ferrite. The synthesized lanthanum ferrite-sorbitol (LFOCo-So) and lanthanum ferrite-mannitol (LFOCo-Mo) were investigated through Ultraviolet-Visible (UV-Vis), X-ray diffraction (XRD), Fourier Transform Infra-Red (FTIR), Raman, Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX), and photoluminescence (PL) techniques to study the effects of the templates on the tunable properties of lanthanum ferrite nanoparticles. The UV-Vis study revealed a remarkably small bandgap (2.09 eV) of LFOCo-So compared to the LFOCo-Mo having a band gap of 2.46 eV. XRD analysis revealed a single-phased structure of LFOCo-So, whereas LFOCo-Mo showed different phases. The calculated crystallite sizes of LFOCo-So and LFOCo-Mo were 22 nm and 39 nm, respectively. FTIR spectroscopy indicated the characteristics of metal-oxygen vibrations of perovskites in both lanthanum ferrite (LFO) nanoparticles, whereas a slight shifting of Raman scattering modes in LFOCo-Mo in contrast to LFOCo-So showed the octahedral distortion of the perovskite by changing the template. SEM micrographs indicated porous particles of lanthanum ferrite with LFOCo-So being more uniformly distributed, and EDX confirmed the stoichiometric ratios of the lanthanum, iron, and oxygen in the fabricated lanthanum ferrite. The high-intensity green emission in the photoluminescence spectrum of LFOCo-So indicated more prominent oxygen vacancies than LFOCo-Mo. The photocatalytic efficiency of synthesized LFOCo-So and LFOCo-Mo was investigated against cefadroxil drug under solar light irradiation. At optimized photocatalytic conditions, LFOCo-So showed higher degradation efficiency of 87% in only 20 min than LFOCo-Mo having photocatalytic activity of 81%. The excellent recyclability of the LFOCo-So reflected that it could be reused without affecting photocatalytic efficiency. These findings showed that sorbitol is a useful template for the lanthanum ferrite particles imparting outstanding features, enabling it to be used as an efficient photocatalyst for environmental remediation.


Asunto(s)
Lantano , Nanopartículas , Lantano/química , Cefadroxilo , Nanopartículas/química
6.
Chemosphere ; 329: 138552, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37003438

RESUMEN

Persistent contaminants in wastewater effluent pose a significant threat to aquatic life and are one of the most significant environmental concerns of our time. Although there are a variety of traditional methods available in wastewater treatment, including adsorption, coagulation, flocculation, ion exchange, membrane filtration, co-precipitation and solvent extraction, none of these have been found to be significantly cost-effective in removing toxic pollutants from the water environment. The upfront costs of these treatment methods are extremely high, and they require the use of harmful synthetic chemicals. For this reason, the development of new technologies for the treatment and recycling of wastewater is an absolute necessity. Our way of life can be made more sustainable by the synthesis of adsorbents based on biomass, making the process less harmful to the environment. Biopolymers offer a sustainable alternative to synthetic polymers, which are manufactured by joining monomer units through covalent bonding. This review presents a detailed classification of biopolymers such as pectin, alginate, chitosan, lignin, cellulose, chitin, carrageen, certain proteins, and other microbial biomass compounds and composites, with a focus on their sources, methods of synthesis, and prospective applications in wastewater treatment. A concise summary of the extensive body of knowledge on the fate of biopolymers after adsorption is also provided. Finally, consideration is given to open questions about future developments leading to environmentally friendly and economically beneficial applications of biopolymers.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Aguas Residuales , Biopolímeros/química , Celulosa/química , Quitina , Agua , Contaminantes Químicos del Agua/química , Adsorción
7.
Environ Res ; 229: 115861, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37062477

RESUMEN

Although rapid industrialization has made life easier for humans, several associated issues are emerging and harming the environment. Wastewater is regarded as one of the key problems of the 21st century due to its massive production every year and requires immediate attention from all stakeholders to protect the environment. Since the introduction of nanotechnology, bismuth-based nanomaterials have been used in variety of applications. Various techniques, such as hydrothermal, solvo-thermal and biosynthesis, have been reported for synthesizing these materials, etc. Among these, biosynthesis is eco-friendly, cost-effective, and less toxic than conventional chemical methods. The prime focuses of this review are to elaborate biosynthesis of bismuth-based nanomaterials via bio-synthetic agents such as plant, bacteria and fungi and their application in wastewater treatment as anti-pathogen/photocatalyst for pollutant degradation. Besides this, future perspectives have been presented for the upcoming research in this field, along with concluding remarks.


Asunto(s)
Contaminantes Ambientales , Nanoestructuras , Humanos , Aguas Residuales , Bismuto , Nanotecnología/métodos
8.
Chemosphere ; 328: 138476, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36963573

RESUMEN

The unplanned anthropogenic activities and raced industrial revolution detrimentally causes serious threat to terrestrial and aquatic life. A high discharge of wastewater from industries using dyes affects living organisms and the environment. This paper presents studies on polycationic selenides (PCS) synthesized by hydrothermal methods for photocatalytic degradation of dyes. The synthesized PCS were confirmed by various characterization techniques such as FTIR, SEM, EDX, UV/Vis, and XRD. The FTIR spectra revealed characteristic band at 843, 548 cm-1, and 417 cm-1 due to the M - Se stretching and intrinsic stretching vibrations, respectively. The optical bandgap of polycationic selenide lies in the visible light region (2.36 eV). The SEM images showed that PCS has a spherical shape with an average crystallite size of 29.23 nm calculated from XRD data using Scherer's equation. The PCS has a point of zero charge (PZC) at pH 7. The efficiency of synthesized PCS photocatalyst was confirmed in terms of its activity towards Eosin (EY) and Crystal violet (CV) dyes mineralization. The photocatalytic degradation for EY and CV dyes at optimum conditions was 99.47% and 99.31% and followed second order reactions kinetics with 1.4314 and 0.551 rate constant, respectively. The polynomial quadratic model is the best-fitted response surface methodology (RSM) model having a maximum desirability factors value and significant terms, with R2 (0.9994) and adj R2 values (1.0).


Asunto(s)
Luz Solar , Purificación del Agua , Aguas Residuales , Colorantes/química , Textiles , Catálisis
9.
J Helminthol ; 97: e26, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36810301

RESUMEN

In the present world a significant threat to human health is posed by zoonotic diseases. Helminth parasites of ruminants are one of the most common zoonotic organisms on the planet. Among them, trichostrongylid nematodes of ruminants, found worldwide, parasitize humans in different parts of the world with varying rates of incidence, particularly among rural and tribal communities with poor hygiene, pastoral livelihood and poor access to health services. In the Trichostrongyloidea superfamily, Haemonchus contortus, Teladorsagia circumcincta, Marshallagia marshalli, Nematodirus abnormalis and Trichostrongylus spp. are zoonotic in nature. Species of the genus Trichostrongylus are the most prevalent gastrointestinal nematode parasites of ruminants that transmit to humans. This parasite is prevalent in pastoral communities around the world and causes gastrointestinal complications with hypereosinophilia which is typically treated with anthelmintic therapy. The scientific literature from 1938 to 2022 revealed the occasional incidence of trichostrongylosis throughout the world with abdominal complications and hypereosinophilia as the predominant manifestation in humans. The primary means of transmission of Trichostrongylus to humans was found to be close contact with small ruminants and food contaminated by their faeces. Studies revealed that conventional stool examination methods such as formalin-ethyl acetate concentration or Willi's technique combined with polymerase chain reaction-based approaches are important for the accurate diagnosis of human trichostrongylosis. This review further found that interleukin 33, immunoglobulin E, immunoglobulin G1, immunoglobulin G2, immunoglobulin M, histamine, leukotriene C4, 6-keto prostaglandin F1α, and thromboxane B2 are vital in the fight against Trichostrongylus infection with mast cells playing a key role. This review focuses on the prevalence, pathogenicity and immunological aspects of Trichostrongylus spp. in humans.


Asunto(s)
Parasitosis Intestinales , Nematodos , Enfermedades de las Ovejas , Trichostrongyloidea , Tricostrongiliasis , Animales , Humanos , Ovinos , Tricostrongiliasis/epidemiología , Trichostrongylus , Rumiantes , Zoonosis , Inmunoglobulinas , Enfermedades de las Ovejas/parasitología
10.
Assay Drug Dev Technol ; 19(3): 191-203, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33471566

RESUMEN

The challenges with scaffold profiling of cell-based assay includes accelerated cancer cell proliferation, induced scaffold toxicity, and identifying irrelevant cancer cell-based assays in batch assessments. This study investigates profiling carcinoma of breast cancer cells of MCF-7 model systems using silica nanoparticles scaffold sourced from synthetic materials and plant extracts. Herein, the engineered tissue scaffolds were used to create temporary structures for cancer cell attachments, differentiation, and subsequently to assess the metabolic activity of the cancer cell colonies. The cell viability of the cancer cells was assessed using the tetrazolium compound (MTS reagent), which was reduced to colored formazan, to indicate metabolically active cancer cells in a proliferating assay. We aimed to develop cancer cell-based scaffolds that not only mimic the neoplastic activity, but that also allowed synergistic interaction with cisplatin for in vitro assay screening.


Asunto(s)
Nanopartículas , Dióxido de Silicio , Andamios del Tejido , Microambiente Tumoral , Proliferación Celular , Supervivencia Celular , Técnica del Anticuerpo Fluorescente , Humanos , Células MCF-7
11.
Assay Drug Dev Technol ; 19(1): 46-61, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33443468

RESUMEN

Drug attrition rate is the calculation or measure of the clinical efficacy of a candidate drug on a screen platform for a specific period. Determining the attrition rate of a prospective cancer drug is a reliable way of testing the clinical efficacy. A low attrition rate in the last phase of a preclinical trial increases the success of a drug discovery process. It has been reported that the attrition rates of antineoplastic drugs are much higher than for other therapeutic drugs. Among the factors identified for the high attrition rates in antineoplastic drugs are the nature of the screen-based platforms involving human-derived xenografts, extracellular matrix-derived scaffold systems, and the synthetic scaffolds, which all have propensity to proliferate tumor cells at faster rates than in vivo primary tumors. Other factors that affect the high attrition rates are induced scaffold toxicity and the use of assays that are irrelevant, yet affect data processing. These factors contribute to the wide variation in data and systematic errors. As a result, it becomes imperative to filter batch variations and to standardize the data. Importantly, understanding the interplay between the biological milieu and scaffold connections is also crucial. Here the cell viability of MCF-7 (breast cancer cell line) cells exposed to different scaffolds were screened before cisplatin dosing using the calculated p-values. The statistical significance (p-value) of data was calculated using the one-way analysis of variance, with the p-value set as: 0 < p < 0.06. In addition, the half-maximal inhibitory concentration (IC50) of the different scaffolds exposed to MCF-7 cells were calculated with the probit extension model and cumulative distribution (%) of the extension data. The chemotherapeutic dose (cisplatin, 56 mg/m2) reduced the cell viability of MCF-7 cells to 5% within 24 h on the scaffold developed from silica nanoparticles (SNPs) and polyethylene glycol (PEG) formulation (SNP:PEG) mixtures with a ratio of 1:10, respectively.


Asunto(s)
Algoritmos , Antineoplásicos Fitogénicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Nanocompuestos/química , Extractos Vegetales/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Células MCF-7 , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Relación Estructura-Actividad , Células Tumorales Cultivadas
12.
Nanotechnology ; 32(7): 075706, 2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-32942270

RESUMEN

Silicon nitrides, deposited by capacitively coupled plasma (CCP)-type plasma enhanced atomic layer deposition (PEALD), are generally applied to today's nanoscale semiconductor devices, and are currently being investigated in terms of their potential applications in the context of flexible displays, etc. During the PEALD process, 13.56 MHz rf power is generally employed for the generation of reactive gas plasma. In this study, the effects of a higher plasma generation frequency of 162 MHz on both plasma and silicon nitride film characteristics are investigated for the purpose of silicon nitride PEALD, using bis(diethylamino)silane (BDEAS) as the silicon precursor, and N2 plasma as the reactant gas. The PEALD silicon nitride film deposited using the 162 MHz CCP exhibited improved film characteristics, such as reduced surface roughness, a lower carbon percentage, a higher N/Si ratio, a lower wet etch rate in a diluted HF solution, lower leakage current, and higher electric breakdown field, and more uniform step coverage of the silicon nitride film deposited in a high aspect ratio trench, as compared to silicon nitride PEALD using 13.56 MHz CCP. These improved PEALD silicon nitride film characteristics are believed to be related to the higher ion density, higher reactive gas dissociation, and lower ion bombardment energy to the substrate observed in N2 plasma with a 162 MHz CCP.

13.
Adv Biosyst ; 4(9): e2000074, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32803868

RESUMEN

Nontoxic carbon nanoparticle samples prepared by both bottom-up and top-down approaches do not inhibit Gram-negative bacterial growth, indicating excellent biocompatibilities. However, cell growth inhibitory efficacies increase considerably when the carbon nanoparticles are conjugated with the antibiotic tetracycline. In tetracycline-resistant bacteria, these efficacies can approach tenfold higher activities when compared to tetracycline alone. No structural abnormality such as membrane disruptions is evident in the tested bacterial strains; this is in contrast with other nanocarbon systems such as graphene oxides, carbon nanotubes, and amine-functionalized carbon nanoparticles which do exhibit membrane disruptions. In comparison, the tetracycline-conjugated carbon nanoparticles induce membrane perturbations (but not membrane disruptions), inhibiting bacterial efflux mechanisms. It is proposed that when tetracycline is conjugated to the surface of carbon nanoparticles, it functions to direct the nanoparticles to membrane-associated tetracycline efflux pumps, thereby blocking and subsequently inhibiting their function. The conjugation between biocompatible carbon nanoparticles and subtherapeutic but well-established antibiotic molecules may provide hybrid antibiotic assembly strategies resulting in effective multidrug efflux inhibition for combating antibiotic resistance.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Nanotubos de Carbono/química , Tetraciclina , Antibacterianos/química , Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Bacterias Gramnegativas/citología , Bacterias Gramnegativas/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Tetraciclina/química , Tetraciclina/farmacología
14.
Mol Carcinog ; 59(10): 1209-1226, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32835442

RESUMEN

Sal-like protein 4 (SALL4) is overexpressed in breast cancer and might contribute to breast cancer progression, but the molecular mechanism remains unknown. Here, we found that within a group of 371 ethnic Chinese breast cancer patients, SALL4 was associated with lower grade (P = .002) and progesterone receptor positivity (P = .004) for overall cases; lower Ki67 (P = .045) and high vimentin (P = .007) for luminal cases. Patients with high SALL4 expression in lymph node metastasis showed a significantly worse survival than those with low expression. Knockout of SALL4 in a triple-negative breast cancer cell line MDA-MB-231-Red-FLuc-GFP led to suppressed ability in proliferation, clonogenic formation, migration, and mammosphere formation in vitro, tumorigenicity and lung colonization in vivo. On the other hand, overexpression of SALL4 enhanced migration and mammosphere formation in vitro and tumorigenicity in vivo. Mechanistically, there was a positive correlation between SALL4 expression and mesenchymal markers including Zinc finger E-box binding homeobox 1 (ZEB1), vimentin, Slug, and Snail in vivo. Chromatin immunoprecipitation experiment indicated that SALL4 can bind to the promoter region of vimentin (-778 to -550 bp). Taken together, we hypothesize that SALL4 promotes tumor progression in breast cancer by inducing the mesenchymal markers like vimentin through directly binding to its promoter. Increased SALL4 level in metastatic lymph node relative to the primary site is an important poor survival marker in breast cancer.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/secundario , Factores de Transcripción/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Adulto , Anciano , Anciano de 80 o más Años , Animales , Apoptosis , Biomarcadores de Tumor/genética , Movimiento Celular , Proliferación Celular , Femenino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Invasividad Neoplásica , Pronóstico , Factores de Transcripción/genética , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto , Adulto Joven
15.
J R Soc Interface ; 17(167): 20200180, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32574540

RESUMEN

Nanozymes are nanomaterials with intrinsic magnetism and superparamagnetic properties. In the presence of an external magnet, nanozyme particles aggregate and redisperse without a foreign attraction. We evaluated the performances of nanozyme by changing the biosensing platforms and substituting other biological variants for a complete cancer assay detection. We investigated the expression of morphological variants in the transmission of signals using an electrochemical method. The signal responses, including signal enhancement with the nanozyme (Au-Fe2O3), showed a wide capturing range (greater than 80%, from 102 to 105 cells ml-1 in phosphate-buffered saline buffer, pH 7.4). The platform showed a fast response time within a dynamic range of 10-105 cells ml-1 for the investigated T47D cancer cell line. We also obtained higher responses for anti-HER2 (human epidermal receptor 2)/streptavidin interface as the biosensing electrode in the presence of T47D cancer cells. The positive assay produced a sixfold increase in current output compared to the negative target or negative biological variant. We calculated the limit of detection at 0.4 U ml-1, and of quantitation at 4 U ml-1 (units per millilitre). However, blood volume amounts in clinical settings may constrain diagnosis and increase detection limit value significantly.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Neoplasias , Biomarcadores de Tumor , Técnicas Electroquímicas , Compuestos Férricos , Oro , Humanos
16.
Lancet Public Health ; 4(1): e28-e40, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30448150

RESUMEN

BACKGROUND: Low emission zones (LEZ) are an increasingly common, but unevaluated, intervention aimed at improving urban air quality and public health. We investigated the impact of London's LEZ on air quality and children's respiratory health. METHODS: We did a sequential annual cross-sectional study of 2164 children aged 8-9 years attending primary schools between 2009-10 and 2013-14 in central London, UK, following the introduction of London's LEZ in February, 2008. We examined the association between modelled pollutant exposures of nitrogen oxides (including nitrogen dioxide [NO2]) and particulate matter with a diameter of less than 2·5 µm (PM2·5) and less than 10 µm (PM10) and lung function: postbronchodilator forced expiratory volume in 1 s (FEV1, primary outcome), forced vital capacity (FVC), and respiratory or allergic symptoms. We assigned annual exposures by each child's home and school address, as well as spatially resolved estimates for the 3 h (0600-0900 h), 24 h, and 7 days before each child's assessment, to isolate long-term from short-term effects. FINDINGS: The percentage of children living at addresses exceeding the EU limit value for annual NO2 (40 µg/m3) fell from 99% (444/450) in 2009 to 34% (150/441) in 2013. Over this period, we identified a reduction in NO2 at both roadside (median -1·35 µg/m3 per year; 95% CI -2·09 to -0·61; p=0·0004) and background locations (-0·97; -1·56 to -0·38; p=0·0013), but not for PM10. The effect on PM2·5 was equivocal. We found no association between postbronchodilator FEV1 and annual residential pollutant attributions. By contrast, FVC was inversely correlated with annual NO2 (-0·0023 L/µg per m3; -0·0044 to -0·0002; p=0·033) and PM10 (-0·0090 L/µg per m3; -0·0175 to -0·0005; p=0·038). INTERPRETATION: Within London's LEZ, a smaller lung volume in children was associated with higher annual air pollutant exposures. We found no evidence of a reduction in the proportion of children with small lungs over this period, despite small improvements in air quality in highly polluted urban areas during the implementation of London's LEZ. Interventions that deliver larger reductions in emissions might yield improvements in children's health. FUNDING: National Institute for Health Research Biomedical Research Centre at Guy's and St Thomas' National Health Service (NHS) Foundation Trust and King's College London, NHS Hackney, Lee Him donation, and Felicity Wilde Charitable Trust.


Asunto(s)
Contaminación del Aire/estadística & datos numéricos , Trastornos Respiratorios/epidemiología , Niño , Salud Infantil/estadística & datos numéricos , Estudios Transversales , Exposición a Riesgos Ambientales , Humanos , Londres/epidemiología , Salud Urbana/estadística & datos numéricos
17.
Eur Respir J ; 52(2)2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29946002

RESUMEN

Chronic mucus hypersecretion (CMH) contributes to the morbidity and mortality of asthma, and remains uncontrolled by current therapies in the subset of patients with severe, steroid-resistant disease. Altered cross-talk between airway epithelium and airway smooth muscle cells (ASMCs), driven by pro-inflammatory cytokines such as interleukin (IL)-1ß, provides a potential mechanism that influences CMH. This study investigated mechanisms underlying CMH by comparing IL-1ß-induced gene expression profiles between asthma and control-derived ASMCs and the subsequent paracrine influence on airway epithelial mucus production in vitroIL-1ß-treated ASMCs from asthmatic patients and healthy donors were profiled using microarray analysis and ELISA. Air-liquid interface (ALI)-cultured CALU-3 and primary airway epithelial cells were treated with identified candidates and mucus production assessed.The IL-1ß-induced CCL20 expression and protein release was increased in ASMCs from moderate compared with mild asthmatic patients and healthy controls. IL-1ß induced lower MIR146A expression in asthma-derived ASMCs compared with controls. Decreased MIR146A expression was validated in vivo in bronchial biopsies from 16 asthmatic patients versus 39 healthy donors. miR-146a-5p overexpression abrogated CCL20 release in ASMCs. CCL20 treatment of ALI-cultured CALU-3 and primary airway epithelial cells induced mucus production, while CCL20 levels in sputum were associated with increased levels of CMH in asthmatic patients.Elevated CCL20 production by ASMCs, possibly resulting from dysregulated expression of the anti-inflammatory miR-146a-5p, may contribute to enhanced mucus production in asthma.


Asunto(s)
Asma/metabolismo , Quimiocina CCL20/metabolismo , Interleucina-1beta/farmacología , MicroARNs/metabolismo , Miocitos del Músculo Liso/metabolismo , Adolescente , Adulto , Anciano , Asma/tratamiento farmacológico , Estudios de Casos y Controles , Células Cultivadas , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Femenino , Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Moco/metabolismo , Miocitos del Músculo Liso/efectos de los fármacos , Esputo/metabolismo , Adulto Joven
18.
J Cell Biol ; 216(4): 1163-1181, 2017 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-28264914

RESUMEN

Cellular injury and death are ubiquitous features of disease, yet tools to detect them are limited and insensitive to subtle pathological changes. Acridine orange (AO), a nucleic acid dye with unique spectral properties, enables real-time measurement of RNA and DNA as proxies for cell viability during exposure to various noxious stimuli. This tool illuminates spectral signatures unique to various modes of cell death, such as cells undergoing apoptosis versus necrosis/necroptosis. This new approach also shows that cellular RNA decreases during necrotic, necroptotic, and apoptotic cell death caused by demyelinating, ischemic, and traumatic injuries, implying its involvement in a wide spectrum of tissue pathologies. Furthermore, cells with pathologically low levels of cytoplasmic RNA are detected earlier and in higher numbers than with standard markers including TdT-mediated dUTP biotin nick-end labeling and cleaved caspase 3 immunofluorescence. Our technique highlights AO-labeled cytoplasmic RNA as an important early marker of cellular injury and a sensitive indicator of various modes of cell death in a range of experimental models.


Asunto(s)
Naranja de Acridina/metabolismo , Apoptosis/fisiología , Muerte Celular/fisiología , Necrosis/patología , Ácidos Nucleicos/metabolismo , Animales , Caspasa 3/metabolismo , Línea Celular , Nucleótidos de Desoxiuracil/metabolismo , Humanos , Etiquetado Corte-Fin in Situ/métodos , Ratones Endogámicos C57BL , Necrosis/metabolismo , ARN/metabolismo
19.
ACS Appl Mater Interfaces ; 8(48): 33102-33111, 2016 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-27934198

RESUMEN

We report carbon nanodots that can be utilized as effective color converting phosphors for the production of white light-emitting diodes (LEDs). Blue-excitable and yellow-emitting carbon nanodots, functionalized with 3-(imidazolidin-2-on-1-yl)propylmethyldimethoxysilane (IPMDS)-derived moieties (IS-CDs), are synthesized by a novel one-pot reaction in which the products from the initial reaction occurring between urea and 3-(2-aminoethylamino)propylmethyl-dimethoxysilane (AEPMDS) are further treated with citric acid. Distinctive from the majority of carbon nanodots reported previously, IS-CDs emit at 560 nm, under 460 nm excitation, with a quantum yield of 44%. Preliminary toxicity studies, assessed by the Artemia franciscana nauplii (brine shrimp larvae) bioassay, indicate that IS-CDs are largely nontoxic. Furthermore, the IS-CDs form flexible and transparent films without the need of encapsulating agents, and the solid films retain the optical properties of solvated IS-CDs. These features indicate an immense potential for the IS-CDs as an environmental-friendly, blue-excitable carbon nanodot-based phosphor in solid-state lighting devices.

20.
Sci Rep ; 6: 20461, 2016 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-26830450

RESUMEN

Leukotriene E4 (LTE4) the most stable of the cysteinyl leukotrienes (cysLTs) binds poorly to classical type 1 (CysLT1) and 2 (CysLT2) receptors although it induces potent responses in human airways in vivo, such as bronchoconstriction, airway hyperresponsiveness and inflammatory cell influx suggesting the presence of a novel receptor that preferentially responds to LTE4. To identify such a receptor two human mast cell lines, LAD2 and LUVA, were selected that differentially responded to LTE4 when analysed by intracellular signalling and gene expression. Comparative transcriptome analysis and recombinant gene overexpression experiments revealed CysLT1 as a receptor responsible for potent LTE4-induced response in LAD2 but not in LUVA cells, an observation confirmed further by gene knockdown and selective inhibitors. Lentiviral overexpression of CysLT1 in LUVA cells augmented intracellular calcium signalling induced by LTE4 but did not restore full agonist responses at the gene expression level. Our data support a model where both an increased expression of Gαq-coupled CysLT1, and sustained intracellular calcium mobilisation and extracellular signal-regulated kinase (Erk) activation, are required for LTE4-mediated regulation of gene expression in human cells. Our study shows for the first time that CysLT1 expression is critically important for responsiveness to LTE4 within a human cell system.


Asunto(s)
Regulación de la Expresión Génica , Leucotrieno E4/metabolismo , Receptores de Leucotrienos/agonistas , Receptores de Leucotrienos/metabolismo , Calcio/metabolismo , Línea Celular , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Expresión Génica , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Leucotrieno E4/farmacología , Mastocitos/efectos de los fármacos , Mastocitos/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/genética , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Leucotrienos/genética , Transducción de Señal/efectos de los fármacos , Transcriptoma
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