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1.
Scand J Child Adolesc Psychiatr Psychol ; 11(1): 108-119, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37637869

RESUMO

Background: In the majority of cases, attention deficit hyperactivity disorder (ADHD) is accompanied by one or more comorbid disorders, with the oppositional defiant disorder (ODD) being one of the most frequently diagnosed comorbid disorders. There is a lack of systematic reviews addressing the evidence for an association between the independent environmental and psychosocial risk factors associated with ADHD, ODD, and Conduct Disorder (CD). Objective: This study aims to determine the link between ADHD and ODD/CD, specifically in terms of the most up-to-date environmental and psychosocial risk factors in the development of these illnesses. Results: Eleven studies were included in this systematic review. Among these, ten studies involved environmental risk factors, and only one involved socioeconomic risk factors as exposure. Of the ten studies highlighting the environmental risk factors, six studies reported perinatal risk factors, three reported Atopic diseases as exposure measures, and one involved exposure to energy and coffee drinks. We have found that the most common risk factors associated with ADHD, ODD and CD in Europe and North America were Perinatal risk factors. In contrast, the risk factors of Atopic diseases were more common in Asia. Conclusions: Most of the studies included in our systematic review fall within the scope of environmental risk factors were perinatal risk factors and atopic diseases are the most common risk factors. However, only one article highlighted the association of socioeconomic risk factors as an exposure. Our review results suggest the need for more research focused on psychosocial risk factors for ADHD and comorbid ODD/CD. Further research is required with the primary objective of investigating this association in greater depth and examining the possible mechanisms at varying levels is needed.

2.
Biosensors (Basel) ; 13(6)2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37366953

RESUMO

The ultimate objective of this research work is to design a sensitive and selective electrochemical sensor for the efficient detection of ascorbic acid (AA), a vital antioxidant found in blood serum that may serve as a biomarker for oxidative stress. To achieve this, we utilized a novel Yb2O3.CuO@rGO nanocomposite (NC) as the active material to modify the glassy carbon working electrode (GCE). The structural properties and morphological characteristics of the Yb2O3.CuO@rGO NC were investigated using various techniques to ensure their suitability for the sensor. The resulting sensor electrode was able to detect a broad range of AA concentrations (0.5-1571 µM) in neutral phosphate buffer solution, with a high sensitivity of 0.4341 µAµM-1cm-2 and a reasonable detection limit of 0.062 µM. The sensor's great sensitivity and selectivity allowed it to accurately determine the levels of AA in human blood serum and commercial vitamin C tablets. It demonstrated high levels of reproducibility, repeatability, and stability, making it a reliable and robust sensor for the measurement of AA at low overpotential. Overall, the Yb2O3.CuO@rGO/GCE sensor showed great potential in detecting AA from real samples.


Assuntos
Grafite , Nanocompostos , Humanos , Grafite/química , Ácido Ascórbico , Reprodutibilidade dos Testes , Nanocompostos/química , Carbono/química , Eletrodos , Técnicas Eletroquímicas/métodos
3.
Environ Sci Pollut Res Int ; 30(22): 61710-61725, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36933133

RESUMO

Appropriate material selection and proper understanding of bandgap modification are key factors for the development of efficient photocatalysts. Herein, we developed an efficient, well-organized visible light oriented photocatalyst based on g-C3N4 in association with polymeric network of chitosan (CTSN) and platinum (Pt) nanoparticles utilizing a straightforward chemical approach. Modern techniques like XRD, XPS, TEM, FESEM, UV-Vis, and FTIR spectroscopy were exploited for characterization of synthesized materials. XRD results confirmed the involvement of α-polymorphic form of CTSN in graphitic carbon nitride. XPS investigation confirmed the establishment of trio photocatalytic structure among Pt, CTSN, and g-C3N4. TEM examination showed that the synthesized g-C3N4 possesses fine fluffy sheets like structure (100 to 500 nm in size) intermingled with a dense layered framework of CTSN with good dispersion of Pt nanoparticles on g-C3N4 and CTSN composite structure. The bandgap energies for g-C3N4, CTSN/g-C3N4, and Pt@ CTSN/g-C3N4 photocatalysts were found to be 2.94, 2.73, and 2.72 eV, respectively. The photodegradation skills of each created structure have been examined on antibiotic gemifloxacin mesylate and methylene blue (MB) dye. The newly developed Pt@CTSN/g-C3N4 ternary photocatalyst was found to be efficacious for the elimination of gemifloxacin mesylate (93.3%) in 25 min and MB (95.2%) just in 18 min under visible light. Designed Pt@CTSN/g-C3N4 ternary photocatalytic framework exhibited ⁓ 2.20 times more effective than bare g-C3N4 for the destruction of antibiotic drug. This study provides a simple route towards the designing of rapid, effective visible light oriented photocatalyts for the existing environmental issues.


Assuntos
Quitosana , Nanopartículas , Antibacterianos/química , Gemifloxacina , Azul de Metileno/química , Platina , Catálise , Luz
4.
Polymers (Basel) ; 15(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36987136

RESUMO

Nowadays, synthetic polymers are used in medical applications due to their special biodegradable, biocompatible, hydrophilic, and non-toxic properties. The materials, which can be used for wound dressing fabrication with controlled drug release profile, are the need of the time. The main aim of this study was to develop and characterize polyvinyl alcohol/polycaprolactone (PVA/PCL) fibres containing a model drug. A dope solution comprising PVA/PCL with the drug was extruded into a coagulation bath and became solidified. The developed PVA/PCL fibres were then rinsed and dried. These fibres were tested for Fourier transform infrared spectroscopy, linear density, topographic analysis, tensile properties, liquid absorption, swelling behaviour, degradation, antimicrobial activity, and drug release profile for improved and better healing of the wound. From the results, it was concluded that PVA/PCL fibres containing a model drug can be produced by using the wet spinning technique and have respectable tensile properties; adequate liquid absorption, swelling %, and degradation %; and good antimicrobial activity with the controlled drug release profile of the model drug for wound dressing applications.

5.
Sci Total Environ ; 867: 161484, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36639001

RESUMO

Aerosols undergo significant changes due to water uptake under high RH conditions, leading to changes in physical, optical, and chemical properties. Detailed assessment and investigation are needed to understand better aerosol liquid water content (ALWC) characteristics in highly polluted regions like Delhi. Therefore, in this study, we examined the mass concentration and the factors governing the ALWC associated with PM2.5 in Delhi for two winters (Dec 2019 to Jan 2020 and Dec 2020 to Feb 2021) using the real-time measurements of NR-PM2.5 from Aerodyne aerosol chemical speciation monitor (ACSM) and the application of thermodynamic modeling (ISORROPIA II). The average NR-PM2.5 mass concentration in the 2020-2021 winter was 152 µg/m3, about 50 % higher than the average mass concentration of 102 µg/m3 in 2019-2020. Consequently, the ALWC was also 60 % higher during 2020-2021, with an average mass concentration of 150 µg/m3. ALWC increased exponentially with RH and is significant when RH > 80 %. Further, all the inorganic components of NR-PM2.5 were found to contribute significantly to ALWC uptake; however, the relative contribution varied in different RH conditions. Ammonium sulphate dominated the ALWC uptake among the inorganic components at low RH, but ammonium nitrate was the dominant contributor at high RH. The decreased chloride mass fraction in inorganics in the recent winters reduced its relative contribution to ALWC. High ALWC mass concentration during high PM2.5 and high RH leads to a significant reduction in visibility. We further validated this visibility reduction by estimating the enhanced light scattering coefficient (f(RH)) and found that the hygroscopic growth is responsible for the enhanced visibility reduction during high RH conditions (> 85 %) when light scattering efficiency increased by a factor of >3.5. Sensitivity tests of f(RH) on mass concentration of inorganic salts showed that all the salts contributed almost equally. As revealed in our study, variations in PM2.5 mass concentration and composition despite similar meteorological conditions between different winters indicate changing regional aerosol emissions. Therefore, long-term observations of ALWC and PM2.5 chemical composition are required to arrive at actionable measures and mitigation strategies. Further, the focus should be on reducing the overall inorganic mass concentrations of PM2.5 in general, decreasing the absolute ALWC, and improving visibility.

6.
Langmuir ; 38(51): 16203-16213, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36516225

RESUMO

Developing high-performance, safer, and affordable flexible batteries is of urgent need to power the fast-growing flexible electronics market. In this respect, zinc-ion chemistry employing aqueous-based electrolytes represents a promising combination considering the safety, cost efficiency, and both high energy and high-power output. Herein, we represent a high-performance flexible in-plane aqueous zinc-ion miniaturized battery constructed with all electrodeposited electrodes, i.e., MnO2 cathode and zinc anode with polyimide-derived interdigital patterned laser-scribed carbon (LSC) as the current collector as well as the template for electrodeposition. The LSC possesses a cross-linked network of graphitic carbon sheet, which offers large surface area over low footprint and ensures active materials loading with a robust conductive network. The LSC with high zincophilic characteristic also offers dendrite-free zinc deposition with very low Zn2+ plating stripping overpotential. Benefitting from the Zn//MnO2-rich redox chemistry, the ability of the 3D LSC network to uniformly distribute reaction sites, and the architectural merits of in-plane interdigitated electrode configuration, we report very high capacity values of ∼549 mAh/g (or ∼523 µAh/cm2) and 148 mAh/g (or 140 µAh/cm2) at 0.1 A/g (0.095 mA/cm2) and 2 A/g (1.9 mA/cm2) currents, respectively. The device was also able to maintain a high capacity of 196 mAh/g (areal capacity of 76.19 µAh/cm2) at 1 A/g (0.95 mA/cm2) current after 1350 cycles. The flexibility of the device was demonstrated in polyacryl amide (PAM) gel polymer soaked with a 2 M ZnSO4 and 0.2 M MnSO4 electrolyte, which exhibited a comparable specific capacity of ∼102-110 mAh/g in flat condition and different bending (100° or 160° bending) conditions. The device does not use any conventional current collector, separator, and conductive or polymer additives. The overall process is highly scalable and can be completed in less than a couple of hours.

7.
Biosensors (Basel) ; 12(11)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36354499

RESUMO

In this study, a selective 4-nitrophenol (4-NP) sensor was developed onto a glassy carbon electrode (GCE) as an electron-sensing substrate, which decorated with sol-gel, prepared Pt nanoparticles- (NPs) embedded polypyrole-carbon black (PPy-CB)/ZnO nanocomposites (NCs) using differential pulse voltammetry. Characterizations of the NCs were performed using Field Emission Scanning Electron Microscopy (FESEM), Energy-Dispersive Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS), Ultraviolet-visible Spectroscopy (UV-vis), Fourier Transform Infrared Spectroscopy (FTIR), High Resolution Transmission Electron Microscopy (HRTEM), and X-ray Diffraction Analysis (XRD). The GCE modified by conducting coating binders [poly(3,4-ethylenedioxythiophene) polystyrene sulfonate; PEDOT:PSS] based on Pt NPs/PPy-CB/ZnO NCs functioned as the working electrode and showed selectivity toward 4-NP in a phosphate buffer medium at pH 7.0. Our analysis of 4-NP showed the linearity from 1.5 to 40.5 µM, which was identified as the linear detection range (LDR). A current versus concentration plot was formed and showed a regression co-efficient R2 of 0.9917, which can be expressed by ip(µA) = 0.2493C(µM) + 15.694. The 4-NP sensor sensitivity was calculated using the slope of the LDR, considering the surface area of the GCE (0.0316 cm2). The sensitivity was calculated as 7.8892 µAµM-1cm-2. The LOD (limit of detection) of the 4-NP was calculated as 1.25 ± 0.06 µM, which was calculated from 3xSD/σ (SD: Standard deviation of blank response; σ: Slope of the calibration curve). Limit of quantification (LOQ) is also calculated as 3.79 µM from LOQ = 10xLOD/3.3. Sensor parameters such as reproducibility, response time, and analyzing stability were outstanding. Therefore, this novel approach can be broadly used to safely fabricate selective 4-NP sensors based on nanoparticle-decorated nanocomposite materials in environmental measurement.


Assuntos
Nanopartículas , Óxido de Zinco , Óxido de Zinco/química , Fuligem , Reprodutibilidade dos Testes , Limite de Detecção , Eletrodos , Nanopartículas/química , Carbono/química
8.
Zootaxa ; 5019(1): 1-90, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34810423

RESUMO

The types specimens of many taxa described by Chandy Kurian were considered lost for many years, which prevented the recognition of the species delimited by him. Fifty holotypes have been rediscovered in the National Forest Insect Collection of Forest Research Institute, Dehradun, Uttarakhand, India. Forty-five types belong to Bethylidae (Cephalonomia tritici, Chlorepyris biharina, C. mackenziei, C. pusana, C. sanctipauli, Epyris agraensis, E. agrensis, E. bombayensis, E. delhiensis, E. duni, E. duttai, E. indicae, E. manii, E. patnae, E. pusae, E. shishami, Goniozus ahmeadi, G. chatterjii, G. chowdhari, G. hybleae, G. lygropiae, G. madrassippattanami, G. marasmi, G. mori, G. morindae, G. nephoterycis, G. nilamburensis, G. pulveriae, G. salvadorae, G. sanctijohannis, G. thalasodi, Laelius agraensis, Odontepyris argyriae, O. batrae, O. cirphi, O. hypsipylae, O. indicus, Pristepyris agraensis, Pristocera govindrami, Sclerodermus delhiensis, Sc. hardwickiae, Sc. mori, Sc. raonis, Sulcomesitius bahaduri and Su. duni), one to Chrysididae (Lustrina assamensis), three to Dryinidae (Lestodryinus guptai, Neodryinus karnalensis and N. pusae) and one to Formicidae (Neoclystopsenella luffae). Six new combinations are proposed: Epyris mackenziei comb. nov. from Chlorepyris; Formosiepyris agraensis comb. nov. from Epyris; Holepyris raonis comb. nov. from Sclerodermus; Holepyris patnae comb. nov. from Epyris; Pristocera agraensis comb. nov. from Pristepyris; and Trachepyris sanctipauli comb. nov. from Chlorepyris. We also provide updated diagnoses, as well as detailed remarks and photographs for all types rediscovered. In addition, we provide researchers worldwide with valuable taxonomic information for the Bethylidae, Chrysididae, Dryinidae and Formicidae described by Kurian. A review of Bethylidae from India and a tribute to Chandy Kurian has also been provided.


Assuntos
Formigas , Academias e Institutos , Animais , Florestas , Índia , Masculino
9.
BMJ Case Rep ; 14(4)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33893126

RESUMO

A 13-year-old girl with moderate intellectual disability and autism spectrum disorder (ASD) was admitted to the paediatric high-dependency unit following an 8-week history of altered mental status and motor behaviour. Her symptoms emerged followed shortly after discontinuation of risperidone, an atypical antipsychotic previously commenced to manage disruptive behaviour associated with ASD. On physical examination, the patient presented with negativism, grimacing, automatic obedience, waxy flexibility and ambitendency. Blood tests, neuroimaging and lumbar puncture failed to reveal an acute infectious or neurological precipitant. She responded immediately to a trial of intramuscular lorazepam titrated to a total daily dose of 12 mg. This case presents challenges of accurately diagnosing and managing catatonic symptoms in adolescent patients with ASD. We also discuss the potential risk of precipitating catatonia following the discontinuation of antipsychotic treatment that has been prescribed for a prolonged duration.


Assuntos
Antipsicóticos , Transtorno do Espectro Autista , Catatonia , Adolescente , Antipsicóticos/efeitos adversos , Transtorno do Espectro Autista/tratamento farmacológico , Catatonia/induzido quimicamente , Catatonia/diagnóstico , Catatonia/tratamento farmacológico , Feminino , Humanos , Lorazepam/uso terapêutico , Risperidona/efeitos adversos
10.
Environ Int ; 153: 106541, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33845290

RESUMO

The Government of India (GOI) announced a nationwide lockdown starting 25th March 2020 to contain the spread of COVID-19, leading to an unprecedented decline in anthropogenic activities and, in turn, improvements in ambient air quality. This is the first study to focus on highly time-resolved chemical speciation and source apportionment of PM2.5 to assess the impact of the lockdown and subsequent relaxations on the sources of ambient PM2.5 in Delhi, India. The elemental, organic, and black carbon fractions of PM2.5 were measured at the IIT Delhi campus from February 2020 to May 2020. We report source apportionment results using positive matrix factorization (PMF) of organic and elemental fractions of PM2.5 during the different phases of the lockdown. The resolved sources such as vehicular emissions, domestic coal combustion, and semi-volatile oxygenated organic aerosol (SVOOA) were found to decrease by 96%, 95%, and 86%, respectively, during lockdown phase-1 as compared to pre-lockdown. An unforeseen rise in O3 concentrations with declining NOx levels was observed, similar to other parts of the globe, leading to the low-volatility oxygenated organic aerosols (LVOOA) increasing to almost double the pre-lockdown concentrations during the last phase of the lockdown. The effect of the lockdown was found to be less pronounced on other resolved sources like secondary chloride, power plants, dust-related, hydrocarbon-like organic aerosols (HOA), and biomass burning related emissions, which were also swayed by the changing meteorological conditions during the four lockdown phases. The results presented in this study provide a basis for future emission control strategies, quantifying the extent to which constraining certain anthropogenic activities can ameliorate the ambient air. These results have direct relevance to not only Delhi but the entire Indo-Gangetic plain (IGP), citing similar geographical and meteorological conditions common to the region along with overlapping regional emission sources. SUMMARY OF MAIN FINDINGS: We identify sources like vehicular emissions, domestic coal combustion, and semi-volatile oxygenated organic aerosol (SVOOA) to be severely impacted by the lockdown, whereas ozone levels and, in turn, low-volatility oxygenated organic aerosols (LVOOA) rise by more than 95% compared to the pre-lockdown concentrations during the last phase of the lockdown. However, other sources resolved in this study, like secondary chloride, power plants, dust-related, hydrocarbon-like organic aerosols (HOA), and biomass burning related emissions, were mainly driven by the changes in the meteorological conditions rather than the lockdown.


Assuntos
Poluentes Atmosféricos , COVID-19 , Aerossóis/análise , Poluentes Atmosféricos/análise , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Índia , Material Particulado/análise , SARS-CoV-2 , Estações do Ano , Emissões de Veículos/análise
11.
Int J Mol Sci ; 20(4)2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30781783

RESUMO

Garcinol, a dietary factor obtained from Garcinia indica, modulates several key cellular signaling pathways as well as the expression of miRNAs. Acquired resistance to standard therapies, such as erlotinib and cisplatin, is a hallmark of non-small cell lung cancer (NSCLC) cells that often involves miRNA-regulated epithelial-to-mesenchymal transition (EMT). We used A549 cells that were exposed to transforming growth factor beta 1 (TGF-ß1), resulting in A549M cells with mesenchymal and drug resistant phenotype, and report that garcinol sensitized resistant cells with mesenchymal phenotype to erlotinib as well as cisplatin with significant decrease in their IC50 values. It also potentiated the apoptosis-inducing activity of erlotinib in A549M and the endogenously mesenchymal H1299 NSCLC cells. Further, garcinol significantly upregulated several key EMT-regulating miRNAs, such as miR-200b, miR-205, miR-218, and let-7c. Antagonizing miRNAs, through anti-miRNA transfections, attenuated the EMT-modulating activity of garcinol, as determined by mRNA expression of EMT markers, E-cadherin, vimentin, and Zinc Finger E-Box Binding Homeobox 1 (ZEB1). This further led to repression of erlotinib as well as cisplatin sensitization, thus establishing the mechanistic role of miRNAs, particularly miR-200c and let-7c, in garcinol-mediated reversal of EMT and the resulting sensitization of NSCLC cells to standard therapies.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/genética , Terpenos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Cloridrato de Erlotinib/farmacologia , Humanos , Concentração Inibidora 50 , Neoplasias Pulmonares/tratamento farmacológico , MicroRNAs/metabolismo , Terpenos/química , Terpenos/uso terapêutico , Fator de Crescimento Transformador beta1/farmacologia
12.
Medicines (Basel) ; 6(1)2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30781847

RESUMO

Numerous studies support the potent anticancer activity of resveratrol and its regulation of key oncogenic signaling pathways. Additionally, the activation of sirtuin 1, a deacetylase, by resveratrol has been known for many years, making resveratrol perhaps one of the earliest nutraceuticals with associated epigenetic activity. Such epigenetic regulation by resveratrol, and the mechanism thereof, has attracted much attention in the past decade. Focusing on methylation and acetylation, the two classical epigenetic regulations, we showcase the potential of resveratrol as an effective anticancer agent by virtue of its ability to induce differential epigenetic changes. We discuss the de-repression of tumor suppressors such as BRCA-1, nuclear factor erythroid 2-related factor 2 (NRF2) and Ras Associated Domain family-1α (RASSF-1α) by methylation, PAX1 by acetylation and the phosphatase and tensin homologue (PTEN) by both methylation and acetylation, in addition to the epigenetic regulation of oncogenic NF-κB and STAT3 signaling by resveratrol. Further, we evaluate the literature supporting the potentiation of HDAC inhibitors and the inhibition of DNMTs by resveratrol in different human cancers. This discussion underlines a robust epigenetic activity of resveratrol that warrants further evaluation, particularly in clinical settings.

13.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-630527

RESUMO

SUMMARY Introduction: Urinary tract infection (UTI) is a common bacterial infection affecting children and therefore, prompt recognition and accurate antimicrobial management are vital to prevent kidney damage. This study aims to determine the bacterial pathogens and their patterns of antimicrobial resistance in children presenting with UTI. Methods: A retrospective study of 721 cases, involving children between the ages of 1-day old to 13 years old with culture-proven UTI in Selayang Hospital, Malaysia between January 2007 and December 2011. The bacterial pathogens and antibiotic resistance patterns in the total population, prophylaxis and no prophylaxis groups were studied. Results: The 3 most common organisms isolated in the total population were E.Coli (41.6%), Klebsiella spp. (21.2%) and Enterococcus spp. (11.0%). With regards to the antibiotic resistance, E.Coli resistance rates to ampicillin, cefuroxime and gentamicin were 67.7%, 15.3% and 7.3% respectively. Ampicillin-resistance was also highest in Klebsiella spp. (84.3%), Enterococcus spp. (15.5%) and Proteus spp. (55.5%). Conclusion: E.coli remains to be the leading bacterial pathogen causing UTI in children, with ampicillin-resistance occurring in more than half of these cases. Therefore, accurate choice of antibiotics is important to ensure optimal outcome. In our study, cefuroxime and gentamicin have lower antibiotic resistance rates and can be used in the treatment of UTI in children.


Assuntos
Infecções Urinárias
14.
Nanoscale Res Lett ; 9(1): 62, 2014 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-24502680

RESUMO

We successfully developed a single-step detection and removal unit for Bi(III) ions based on dithizone (DZ) anchored on mesoporous TiO2 with rapid colorometric response and high selectivity for the first time. [(DZ)3-Bi] complex is easily separated and collected by mesoporous TiO2 as adsorbent and preconcentrator without any color change of the produced complex onto the surface of mesoporous TiO2 (TiO2-[(DZ)3-Bi]) at different Bi(III) concentrations. This is because highly potent mesoporous TiO2 architecture provides proficient channeling or movement of Bi(III) ions for efficient binding of metal ion, and the simultaneous excellent adsorbing nature of mesoporous TiO2 provides an extra plane for the removal of metal ions.

15.
Mol Nutr Food Res ; 58(3): 437-46, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24123728

RESUMO

SCOPE: Anticancer polyphenolic nutraceuticals from fruits, vegetables, and spices are generally recognized as antioxidants, but can be prooxidants in the presence of copper ions. We earlier proposed a mechanism for such activity of polyphenols and now we provide data in multiple cancer cell lines in support of our hypothesis. METHODS AND RESULTS: Through multiple assays, we show that polyphenols luteolin, apigenin, epigallocatechin-3-gallate, and resveratrol are able to inhibit cell proliferation and induce apoptosis in different cancer cell lines. Such cell death is prevented to a significant extent by cuprous chelator neocuproine and reactive oxygen species scavengers. We also show that normal breast epithelial cells, cultured in a medium supplemented with copper, become sensitized to polyphenol-induced growth inhibition. CONCLUSION: Since the concentration of copper is significantly elevated in cancer cells, our results strengthen the idea that an important anticancer mechanism of plant polyphenols is mediated through intracellular copper mobilization and reactive oxygen species generation leading to cancer cell death. Moreover, this prooxidant chemopreventive mechanism appears to be a mechanism common to several polyphenols with diverse chemical structures and explains the preferential cytotoxicity of these compounds toward cancer cells.


Assuntos
Cobre/metabolismo , Polifenóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Anticarcinógenos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apigenina/farmacologia , Apoptose/efeitos dos fármacos , Catequina/análogos & derivados , Catequina/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quelantes/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Luteolina/farmacologia , Fenantrolinas/farmacologia , Resveratrol , Estilbenos/farmacologia
16.
ACS Appl Mater Interfaces ; 3(4): 1346-51, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21443253

RESUMO

Due to numerous potential applications of semiconductor transition metal-doped nanomaterials and the great advantages of hydrothermal synthesis in both cost and environmental impact, a significant effort has been employed for growth of copper oxide codoped zinc oxide (CuO codoped ZnO) nanostructures via a hydrothermal route at room conditions. The structural and optical properties of the CuO codoped ZnO nanorods were characterized using various techniques such as UV-visible, Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), etc. The sensing performance has been executed by a simple and reliable I-V technique, where aqueous ammonia is considered as a target analyte. CuO codoped ZnO nanorods of thin film with conducting coating agents on silver electrodes (AgE, surface area of 0.0216 cm(2)) displayed good sensitivity, stability, and reproducibility. The calibration plot is linear over the large dynamic range, where the sensitivity is approximately 1.549 ± 0.10 µA cm(-2 )mM(-1) with a detection limit of 8.9 ± 0.2 µM, based on signal/noise ratio in short response time. Hence, on the bottom of the perceptive communication between structures, morphologies, and properties, it is displayed that the morphologies and the optical characteristics can be extended to a large scale in transition-metal-doped ZnO nanomaterials and efficient chemical sensors applications.

17.
Waste Manag ; 28(9): 1500-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17851062

RESUMO

The aim of this paper is to present an evaluation method that can aid decision makers in a local civic body to prioritize and select appropriate municipal solid waste disposal methods. We introduce a hierarchical network (hiernet) decision structure and apply the analytic network process (ANP) super-matrix approach to measure the relative desirability of disposal alternatives using value judgments as the input of the various stakeholders. ANP is a flexible analytical program that enables decision makers to find the best possible solution to complex problems by breaking down a problem into a systematic network of inter-relationships among the various levels and attributes. This method therefore may not only aid in selecting the best alternative but also helps decision makers to understand why an alternative is preferred over the other options.


Assuntos
Cidades , Tomada de Decisões , Modelos Teóricos , Eliminação de Resíduos/métodos , Conservação dos Recursos Naturais
18.
Behav Brain Res ; 151(1-2): 185-90, 2004 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-15084434

RESUMO

Isolated studies showed that norepinephrinergic REM-OFF neurons are active throughout except during rapid eye movement (REM) sleep when they are inhibited possibly by GABA. Similarly, independent studies have also reported that during REM sleep deprivation those REM-OFF neurons continue firing, that there is increased norepinephrine (NE) in the brain and that increased levels of NE increases the Na-K ATPase activity in the brain. However, it was not known if all those changes were directly related to REM sleep deprivation, what could be the mechanism for such changes and their patho-physiological significance. To confirm the same, based on the reports, mostly from our group, it was hypothesised that GABA antagonist in the locus coeruleus (LC) should at least significantly reduce REM sleep and simultaneously increase Na-K ATPase activity in the brain. To confirm the proposed hypothesis, picrotoxin, a GABA-A receptor antagonist, was bilaterally microinjected every 6 h for 36 h into the LC of freely moving normally behaving rats and the effects on electrophysiological signals signifying sleep-wakefulness and on brain synaptosome Na-K ATPase activity were estimated. The microinjection was done with the help of a remote control pump without handling or disturbing the rats. The findings that REM sleep was significantly reduced and there was associated increase in Na-K ATPase activity confirmed our hypothesis. The results also support our modified (GABA-mediated) model of neural connections in the LC for the regulation of REM sleep. Also, this is probably the first report to simulate REM sleep deprivation using receptor antagonist.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Antagonistas de Receptores de GABA-A , Locus Cerúleo/efeitos dos fármacos , Picrotoxina/farmacologia , Sono REM/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Comportamento Animal , Locus Cerúleo/metabolismo , Masculino , Microinjeções , Ratos , Ratos Wistar , Receptores de GABA-A/efeitos dos fármacos , Receptores de GABA-A/fisiologia , Privação do Sono/fisiopatologia , Sono REM/fisiologia , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/fisiologia , Fatores de Tempo , Vigília/efeitos dos fármacos
19.
J Neurosci Res ; 73(6): 870-5, 2003 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-12949914

RESUMO

It has been shown that rapid eye movement (REM) sleep deprivation increases Na-K ATPase activity. Based on kinetic study, it was proposed that increased activity was due to enhanced turnover of enzyme molecules. To test this, anti-alpha1 Na-K ATPase monoclonal antibody (mAb 9A7) was used to label Na-K ATPase molecules. These labeled enzymes were quantified on neuronal membrane by two methods: histochemically on neurons in tissue sections from different brain areas, and by Western blot analysis in control and REM sleep-deprived rat brains. The specific enzyme activity was also estimated and found to be increased, as in previous studies. The results confirmed our hypothesis that after REM sleep deprivation, increased Na-K ATPase activity was at least partly due to increased turnover of Na-K ATPase molecules in the rat brain.


Assuntos
Encéfalo/enzimologia , Privação do Sono/enzimologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Western Blotting , Encéfalo/anatomia & histologia , Densitometria/instrumentação , Densitometria/métodos , Imuno-Histoquímica/métodos , Masculino , Ratos , Ratos Endogâmicos , Ratos Wistar , Sono REM/fisiologia , Sinaptossomos/metabolismo
20.
J Biosci ; 27(5): 539-51, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12381879

RESUMO

Sleep and wakefulness are instinctive behaviours that are present across the animal species. Rapid eye movement (REM) sleep is a unique biological phenomenon expressed during sleep. It evolved about 300 million years ago and is noticed in the more evolved animal species. Although it has been objectively identified in its present characteristic form about half a century ago, the mechanics of how REM is generated, and what happens upon its loss are not known. Nevertheless, extensive research has shown that norepinephrine plays a crucial role in its regulation. The present knowledge that has been reviewed in this manuscript suggests that neurons in the brain stem are responsible for controlling this state and presence of excess norepinephrine in the brain does not allow its generation. Furthermore, REM sleep loss increases levels of norepinephrine in the brain that affects several factors including an increase in Na-K ATPase activity. It has been argued that such increased norepinephrine is ultimately responsible for REM sleep deprivation, associated disturbances in at least some of the physiological conditions leading to alteration in behavioural expression and settling into pathological conditions.


Assuntos
Norepinefrina/fisiologia , Sono REM/fisiologia , Humanos , Locus Cerúleo/fisiologia , Vigília/fisiologia
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