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1.
J Biol Chem ; 298(1): 101521, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34952004

RESUMEN

CD200R1 is an inhibitory surface receptor expressed in microglia and blood macrophages. Microglial CD200R1 is known to control neuroinflammation by keeping the microglia in resting state, and therefore, tight regulation of its expression is important. CCAAT/enhancer-binding protein ß (CEBPß) is the known regulator of CD200R1 transcription. In the present study, our specific intention was to find a possible posttranscriptional regulatory mechanism of CD200R1 expression. Here we investigated a novel regulatory mechanism of CD200R1 expression following exposure to an environmental stressor, arsenic, combining in silico analysis, in vitro, and in vivo experiments, as well as validation in human samples. The in silico analysis and in vitro studies with primary neonatal microglia and BV2 microglia revealed that arsenic demethylates the promoter of a microRNA, miR-129-5p, thereby increasing its expression, which subsequently represses CD200R1 by binding to its 3'-untranslated region and shuttling the CD200R1 mRNA to the cytoplasmic-processing body in mouse microglia. The role of miR-129-5p was further validated in BALB/c mouse by stereotaxically injecting anti-miR-129. We found that anti-miR-129 reversed the expression of CD200R1, as well as levels of inflammatory molecules IL-6 and TNF-α. Experiments with a CD200R1 siRNA-induced loss-of-function mouse model confirmed an miR-129-5p→CD200R1→IL-6/TNF-α signaling axis. These main findings were replicated in a human cell line and validated in human samples. Taken together, our study revealed miR-129-5p as a novel posttranscriptional regulator of CD200R1 expression with potential implications in neuroinflammation and related complications.


Asunto(s)
Arsénico , MicroARNs , Enfermedades Neuroinflamatorias , Receptores de Orexina , Regiones no Traducidas 3' , Animales , Antagomirs/metabolismo , Interleucina-6/metabolismo , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Microglía/metabolismo , Enfermedades Neuroinflamatorias/metabolismo , Receptores de Orexina/genética , Receptores de Orexina/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
2.
Environ Res ; 218: 115011, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36502908

RESUMEN

Microplastic (MP) pollution has pressing concerns regarding environmental health and the availability of safe food for humans. Information on the occurrence of MP in freshwater biota in the Indian scenario is currently lacking. The present study examined MP contamination in edible and non-edible tissues of widely consumed freshwater fishes. All the fish species (n = 35/species) analyzed had microplastic contamination with the highest MP abundance of 7.86 ± 2.0 items/individual in Channa punctatus followed by Labeo rohita (4.17 ± 0.6 items/individual) and Labeo bata (3.03 ± 0.4 items/individual); whereas MP abundance in small indigenous fishes (SIF) such as Salmostoma bacaila and Puntius amphibius accounts for 0.83 ± 0.13 and 0.77 ± 0.2 items/individual respectively. The principal component analysis results showed a 77.434% variance from two components identified for MP distribution. Fibre type MP was the most dominant type besides fragments and pellets that opined the type of MP required for ecotoxicity assessment, the need of the hour. Raman spectroscopy analysis confirms high-density and low-density polyethylene-type polymers. Evidence of MP in edible tissue indicates the translocation phenomenon resulting in human exposure through the consumption of biota contaminated with MP. Risk assessment revealed a low risk of MP based on its abundance while polymer type indicates a high risk for the fish species investigated. A thorough investigation of the level of adsorbed organic contaminants in the MP is warranted to address the interactive effects on biota. To the best of our knowledge, this is the first detailed report on MP contamination and its risk assessment in Indian freshwater fishes.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Humanos , Plásticos/análisis , Monitoreo del Ambiente , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Peces , Agua Dulce , India , Medición de Riesgo
3.
Int J Phytoremediation ; 25(13): 1793-1800, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37073767

RESUMEN

Rapeseed, the second-most-important vegetable oil source, is cultivated in various areas of India where both groundwater and soil are contaminated with fluoride (F-). Furthermore, the frequent use of F- contaminated groundwater for irrigation leads to accumulation of F- in surface and sub-surface soil. The study aims to compare the morphological and biochemical changes in Brassica juncea L., the variations in its fatty acids (FAs) composition and oil yield, under two regimes of F- contaminated soils: (i) pre-contaminated soil (Tr) and (ii) irrigation with F- contaminated water (Ir). The level of F- (µg g-1) in the plant tissues (root, leaf, and grain) was significantly higher in Ir_10 (18.3, 14.7, and 2.8, respectively) than in Tr_10 (4.3, 2.6, and 0.77, respectively), while the oil yield was significantly lower with Ir_10 (19.5%) than with Tr_10 (44.9%). The phytoremediation potential of F- by Brassica juncea L. is greater in Tr regime than in the Ir regime. The erucic acid content (%), which is detrimental to cardiac health, increased to 67.37% (Ir_10) and 58.3% (Tr_10) from 57.73% (control). Thus, the present study shows that irrigation with F- contaminated water results in greater toxicity and accumulation in plants and is not safe for human health.


Irrigation with F­ contaminated water results in a greater accumulation of F­ in mustard than cultivated on pre-contaminated soil. The level of erucic acid in mustard oil enhances against F­ exposure.


Asunto(s)
Planta de la Mostaza , Contaminantes del Suelo , Humanos , Planta de la Mostaza/química , Ácidos Grasos , Fluoruros , Biodegradación Ambiental , Suelo/química , Agua
4.
Environ Res ; 210: 112927, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35182594

RESUMEN

Fluoride (F-) contamination in groundwater of Unnao district, Uttar Pradesh was reported for the first time in 1994, however comprehensive monitoring of F- in different environmental matrices remains to be undertaken. The presented study reports spatio-temporal monitoring of F- content in groundwater, crops and soil from F- affected district Unnao, in pre-monsoon (PRM), monsoon (MO) and post-monsoon (PMO), to establish F- groundwater-soil-plant continuum. More than 80% of groundwater samples were contaminated with F-> 1.0 mg L-1 with highest level (mg L-1), at Patiyara (3.6 ± 0.64), during PRM > Pathakpur (2.73 ± 0.57) during PMO > Sarukheda (2.40 ± 0.43) during PRM. High Cr in groundwater was observed in Jajmau (7.08 ± 1.42). The level of F- (mg Kg-1) in agricultural soils followed 3.4 ± 0.71 at Patiyara (MO) > 2.9 ± 0.14 at Badlikheda (PRM) 1.89 ± 0.28 at Jagatkhera (PRM). Among the different edible parts of crops in selected sites, highest F- content (mg Kg-1), F- level in grains of Oryza sativa ranged between 0.23 ± 0.02 to 2.01 ± 0.24. Whereas in the edible fruit of Trichosanthes diocia contained 1.47 ± 0.32 and Momordica charantia 1.47 ± 0.02. Leaf of spinach (1.03 ± 0.22) and seed of Brassica juncea (0.73 ± 0.08). Overall, comparing across all the three seasons, level of F- was highest in all the plants during MO, as compared to PRM and PMO. The regression analysis of physiochemical properties of groundwater show negative relationship between Na+ and F- whereas soil alkalinity exhibited strong influence in soil F-. The high F- content in soil and groundwater at Patiyara and Shekhpur also coincided with presence of several brick kilns, possibly contributing to the high F-.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Agricultura , Productos Agrícolas , Monitoreo del Ambiente , Fluoruros/análisis , Agua Subterránea/química , India , Suelo , Contaminantes Químicos del Agua/análisis
5.
Biomacromolecules ; 22(7): 3069-3083, 2021 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-34152738

RESUMEN

The regeneration of critical-sized bone defects with biomimetic scaffolds remains clinically challenging due to avascular necrosis, chronic inflammation, and altered osteogenic activity. Two confounding mechanisms, efficacy manipulation, and temporal regulation dictate the scaffold's bone regenerative ability. Equally critical is the priming of the mesenchymal stromal cells (MSCs) toward lineage-specific differentiation into bone-forming osteoblast, which particularly depends on varied mechanochemical and biological cues during bone tissue regeneration. This study sought to design and develop an optimized osteogenic scaffold, adenosine/epigallocatechin gallate-N,O-carboxymethyl chitosan/collagen type I (AD/EGCG-g-NOCC@clgn I), having osteoinductive components toward swift bone regeneration in a calvarial defect BALB/c mice model. The ex vivo findings distinctly establish the pro-osteogenic potential of adenosine and EGCG, stimulating MSCs toward osteoblast differentiation with significantly increased expression of alkaline phosphatase, calcium deposits, and enhanced osteocalcin expression. Moreover, the 3D matrix recapitulates extracellular matrix (ECM) properties, provides a favorable microenvironment, structural support against mechanical stress, and acts as a reservoir for sustained release of osteoinductive molecules for cell differentiation, proliferation, and migration during matrix osteointegration observed. Evidence from in vivo experiments, micro-CT analyses, histology, and histomorphometry signify accelerated osteogenesis both qualitatively and quantitatively: effectual bone union with enhanced bone formation and new ossified tissue in 4 mm sized defects. Our results suggest that the optimized scaffold serves as an adjuvant to guide bone tissue regeneration in critical-sized calvarial defects with promising therapeutic efficacy.


Asunto(s)
Osteogénesis , Andamios del Tejido , Adenosina , Animales , Regeneración Ósea , Catequina/análogos & derivados , Diferenciación Celular , Quitosano , Colágeno , Ratones , Ratones Endogámicos BALB C
6.
Nucleic Acids Res ; 46(12): 6356-6370, 2018 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-29800374

RESUMEN

4-Aminobiphenyl (ABP) and its structure analog 2-aminofluorene (AF) are well-known carcinogens. In the present work, an unusual sequence effect in the 5'-CTTCTG1G2TCCTCATTC-3' DNA duplex is reported for ABP- and AF-modified G. Specifically, the ABP modification at G1 resulted in a mixture of 67% major groove B-type (B) and 33% stacked (S) conformers, while at the ABP modification at G2 exclusively resulted in the B-conformer. The AF modification at G1 and G2 lead to 25%:75% and 83%:17% B:S population ratios, respectively. These differences in preferred conformation are due to an interplay between stabilizing (hydrogen bonding and stacking that is enhanced by lesion planarity) and destabilizing (solvent exposure) forces at the lesion site. Furthermore, while the B-conformer is a thermodynamic stabilizer and the S-conformer is a destabilizer in duplex settings, the situation is reversed at the single strands/double strands (ss/ds) junction. Specifically, the twisted biphenyl is a better stacker at the ss/ds junction than the coplanar AF. Therefore, the ABP modification leads to a stronger strand binding affinity of the ss/ds junction than the AF modification. Overall, the current work provides conformational insights into the role of sequence and lesion effects in modulating DNA replication.


Asunto(s)
Compuestos de Aminobifenilo/química , Carcinógenos/química , Aductos de ADN/química , Replicación del ADN , Fluorenos/química , Secuencia de Bases , ADN/química , Desoxiguanosina/química , Modelos Moleculares , Resonancia Magnética Nuclear Biomolecular , Conformación de Ácido Nucleico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Resonancia por Plasmón de Superficie , Termodinámica
7.
Nanomedicine ; 17: 210-222, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30708053

RESUMEN

Insulin resistance is thought to be a common link between obesity and Non-Alcoholic Fatty Liver Disease (NAFLD). NAFLD has now reached epidemic status worldwide and identification of molecules or pathways as newer therapeutic strategies either to prevent or overcome insulin resistance seems critical. Dysregulated hepatic lipogenesis (DNL) is a hallmark of NAFLD in humans and rodents. Therefore, reducing DNL accretion may be critical in the development of therapeutics of NAFLD. In our in vivo model (high-fat-diet fed [HFD] obese mice) we found Zinc oxide nanoparticles (ZnO NPs) significantly decreased HFD-induced hepatic steatosis and peripheral insulin resistance. This protective mechanism of ZnO NPs was signaled through hepatic SIRT1-LKB1-AMPK which restricted SREBP-1c within the cytosol limiting its transcriptional ability and thereby ameliorating HFD mediated DNL. These observations indicate that ZnO NP can serve as a therapeutic strategy to improve the physiological homeostasis during obesity and its associated metabolic abnormalities.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Activadores de Enzimas/uso terapéutico , Nanopartículas/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Óxido de Zinc/uso terapéutico , Animales , Dieta Alta en Grasa/efectos adversos , Células Hep G2 , Humanos , Resistencia a la Insulina , Hígado/efectos de los fármacos , Hígado/metabolismo , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Transducción de Señal/efectos de los fármacos
8.
Bioconjug Chem ; 27(11): 2605-2619, 2016 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-27643823

RESUMEN

In cancer treatment, developing ideal anticancer drug delivery systems to target tumor microenvironment by circumventing various physiological barriers still remains a daunting challenge. Here, in our work, a series of pH- and temperature-responsive nanogels based on poly(N-isopropylacrylamide-co-1-propene-2-3-dicarboxylate-co-2-acrylamido-2-methyl-1-propanesulfonate [poly(NIPAAm-IA-AMPS)] cross-linked by ethylene glycol dimethacrylate (EGDMA) were synthesized by random copolymerization. The molar ratio between monomer-comonomers-cross-linker was varied to fine-tune the optimum responsiveness of the nanogels. These optimized nanogels were further coupled to N,O-carboxymethyl chitosan (NOCC) stoichiometrically using EDC-NHS coupling chemistry to enhance the swelling behavior at lower pH. Interestingly, these NOCC-g-nanogels, when dispersed in aqueous media under sonication, attain nanosize and retain their high water-retention capacity with conspicuous pH and temperature responsiveness (viz. nanogel shrinkage in size beyond 35 °C and swelled at acidic pH) in vitro, as reflected by dynamic light scattering data. Doxorubicin (DOX), a potent anticancer drug, was loaded into these nanogels using the physical entrapment method. These drug-loaded nanogels exhibited a slow and sustained DOX release profile at physiological temperature and cytosolic pH. Furthermore, confocal and TEM results demonstrate that these nanogels were swiftly internalized by MCF-7 cells, and cell viability data showed preferential heightened cytotoxicity toward cancer cells (MCF-7 and MDA-MB231) compared to the MCF10A cells (human breast epithelial cell). Furthermore, intracellular DNA damage and cell cycle arrest assays suggest a mitochondrial mediated apoptosis in MCF-7 cells. This study substantiates our NOCC-g-nanogel platform as an excellent modality for passive diffusive loading and targeted release of entrapped drug(s) at physiological conditions in a controlled way for the improved therapeutic efficacy of the drug in anticancer treatment.


Asunto(s)
Quitosano/química , Doxorrubicina/química , Doxorrubicina/farmacología , Portadores de Fármacos/química , Nanoestructuras/química , Resinas Acrílicas/química , Apoptosis/efectos de los fármacos , Transporte Biológico , Puntos de Control del Ciclo Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Daño del ADN , Portadores de Fármacos/metabolismo , Geles , Humanos , Concentración de Iones de Hidrógeno , Células MCF-7 , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Temperatura
9.
Nucleic Acids Res ; 41(2): 869-80, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23180767

RESUMEN

The environmental arylamine mutagens are implicated in the etiology of various sporadic human cancers. Arylamine-modified dG lesions were studied in two fully paired 11-mer duplexes with a -G*CN- sequence context, in which G* is a C8-substituted dG adduct derived from fluorinated analogs of 4-aminobiphenyl (FABP), 2-aminofluorene (FAF) or 2-acetylaminofluorene (FAAF), and N is either dA or dT. The FABP and FAF lesions exist in a simple mixture of 'stacked' (S) and 'B-type' (B) conformers, whereas the N-acetylated FAAF also samples a 'wedge' (W) conformer. FAAF is repaired three to four times more efficiently than FABP and FAF. A simple A- to -T polarity swap in the G*CA/G*CT transition produced a dramatic increase in syn-conformation and resulted in 2- to 3-fold lower nucleotide excision repair (NER) efficiencies in Escherichia coli. These results indicate that lesion-induced DNA bending/thermodynamic destabilization is an important DNA damage recognition factor, more so than the local S/B-conformational heterogeneity that was observed previously for FAF and FAAF in certain sequence contexts. This work represents a novel 3'-next flanking sequence effect as a unique NER factor for bulky arylamine lesions in E. coli.


Asunto(s)
2-Acetilaminofluoreno/química , Compuestos de Aminobifenilo/química , Aductos de ADN/química , Daño del ADN , Reparación del ADN , Desoxiguanosina/análogos & derivados , Fluorenos/química , Secuencia de Bases , Dicroismo Circular , Aductos de ADN/metabolismo , Desoxiguanosina/química , Ensayo de Cambio de Movilidad Electroforética , Endodesoxirribonucleasas/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Modelos Moleculares , Simulación de Dinámica Molecular , Resonancia Magnética Nuclear Biomolecular , Conformación de Ácido Nucleico , Termodinámica
10.
Biochemistry ; 53(24): 4059-71, 2014 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-24915610

RESUMEN

Adduct-induced DNA damage can affect transcription efficiency and DNA replication and repair. We previously investigated the effects of the 3'-next flanking base (G*CT vs G*CA; G*, FABP, N-(2'-deoxyguanosin-8-yl)-4'-fluoro-4-aminobiphenyl; FAF, N-(2'-deoxyguanosin-8-yl)-7-fluoro-2-aminofluorene) on the conformation of arylamine-DNA lesions in relation to E. coli nucleotide excision repair ( Jain , V. , Hilton , B. , Lin , B. , Patnaik , S. , Liang , F. , Darian , E. , Zou , Y. , Mackerell , A. D. , Jr. , and Cho , B. P. ( 2013 ) Nucleic Acids Res. , 41 , 869 - 880 ). Here, we report the differential effects of the same pair of sequences on DNA replication in vitro by the polymerases exofree Klenow fragment (Kf-exo(-)) and Dpo4. We obtained dynamic (19)F NMR spectra for two 19-mer modified templates during primer elongation: G*CA [d(5'-CTTACCATCG*CAACCATTC-3')] and G*CT [d(5'-CTTACCATCG*CTACCATTC-3')]. We found that lesion stacking is favored in the G*CT sequence compared to the G*CA counterpart. Surface plasmon resonance binding results showed consistently weaker affinities for the modified DNA with the binding strength in the order of FABP > FAF and G*CA > G*CT. Primer extension was stalled at (n) and near (n - 1 and n + 1) the lesion site, and the extent of blockage and the extension rates across the lesion were influenced by not only the DNA sequences but also the nature of the adduct's chemical structure (FAF vs FABP) and the polymerase employed (Kf-exo(-) vs Dpo4). Steady-state kinetics analysis with Kf-exo(-) revealed the most dramatic sequence and lesion effects at the lesion (n) and postinsertion (n + 1) sites, respectively. Taken together, these results provide insights into the important role of lesion-induced conformational heterogeneity in modulating translesion DNA synthesis.


Asunto(s)
Compuestos de Aminobifenilo/química , Reparación del ADN , Replicación del ADN , Fluorenos/química , Conformación de Ácido Nucleico , Secuencia de Bases , Aductos de ADN , Daño del ADN , ADN Polimerasa I/metabolismo , Flúor/química , Cinética , Resonancia por Plasmón de Superficie
11.
Nucleic Acids Res ; 40(9): 3939-51, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22241773

RESUMEN

Nucleotide excision repair (NER) is a major repair pathway that recognizes and corrects various lesions in cellular DNA. We hypothesize that damage recognition is an initial step in NER that senses conformational anomalies in the DNA caused by lesions. We prepared three DNA duplexes containing the carcinogen adduct N-(2'-deoxyguanosin-8-yl)-7-fluoro-2-acetylaminofluorene (FAAF) at G(1), G(2) or G(3) of NarI sequence (5'-CCG(1)G(2)CG(3)CC-3'). Our (19)F-NMR/ICD results showed that FAAF at G(1) and G(3) prefer syn S- and W-conformers, whereas anti B-conformer was predominant for G(2). We found that the repair of FAAF occurs in a conformation-specific manner, i.e. the highly S/W-conformeric G(3) and -G(1) duplexes incised more efficiently than the B-type G(2) duplex (G(3)∼G(1)> G(2)). The melting and thermodynamic data indicate that the S- and W-conformers produce greater DNA distortion and thermodynamic destabilization. The N-deacetylated N-(2'-deoxyguanosin-8-yl)-7-fluoro-2-aminofluorene (FAF) adducts in the same NarI sequence are repaired 2- to 3-fold less than FAAF: however, the incision efficiency was in order of G(2)∼G(1)> G(3), a reverse trend of the FAAF case. We have envisioned the so-called N-acetyl factor as it could raise conformational barriers of FAAF versus FAF. The present results provide valuable conformational insight into the sequence-dependent UvrABC incisions of the bulky aminofluorene DNA adducts.


Asunto(s)
2-Acetilaminofluoreno/química , Aductos de ADN/química , Reparación del ADN , Desoxiguanosina/química , Fluorenos/química , Termodinámica , Adenosina Trifosfatasas/metabolismo , Secuencia de Bases , Calorimetría , Dicroismo Circular , Proteínas de Unión al ADN/metabolismo , Desoxirribonucleasas de Localización Especificada Tipo II , Proteínas de Escherichia coli/metabolismo , Resonancia Magnética Nuclear Biomolecular , Conformación de Ácido Nucleico , Desnaturalización de Ácido Nucleico , Espectrometría de Masa por Ionización de Electrospray
12.
Environ Pollut ; 348: 123854, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38527586

RESUMEN

Microplastic (MP) pollution is becoming an emerging environmental concern across aquatic and terrestrial ecosystems. Plastic mulching and the use of pesticides in agriculture can lead to microplastics and agrochemicals in soil, which can result in unintended exposure to non-target organisms. The combined toxicity of multiple stressors represents a significant paradigm shift within the field of ecotoxicology, and its exploration within terrestrial ecosystems involving microplastics is still relatively limited. The present study investigated the combined effects of polyethylene MP (PE-MP) and the agrochemical carbendazim (CBZ) on the earthworm Eisenia fetida at different biological levels of organization. While E. fetida survival and reproduction did not exhibit significant effects following PE-MP treatment, there was a reduction in cocoon and hatchling numbers. Notably, prolonged exposure revealed delayed toxicity, leading to substantial growth impairment. Exposure to CBZ led to significant alterations in the endpoints mentioned above. While there was a decrease in cocoon and hatchling numbers, the combined treatment did not yield significant effects on earthworm reproduction except at higher concentrations. However, lower concentrations of PE-MP alongside CBZ induced a noteworthy decline in biomass content, signifying a form of potentiation interaction. In addition, concurrent exposure led to synergistic effects, from oxidative stress to modifications in vital organs such as the body wall, intestines, and reproductive structures (spermathecae, seminal vesicles, and ovarian follicles). The comparison of multiple endpoints revealed that seminal vesicles and ovarian follicles were the primary targets during the combined exposure. The research findings suggest that there are variable and complex responses to microplastic toxicity in terrestrial ecosystems, especially when combined with other chemical stressors like agrochemicals. Despite these difficulties, the study implies that microplastics can alter earthworms' responses to agrochemical exposure, posing potential ecotoxicological risks to soil fauna.


Asunto(s)
Bencimidazoles , Carbamatos , Oligoquetos , Plaguicidas , Contaminantes del Suelo , Animales , Femenino , Masculino , Microplásticos/toxicidad , Plásticos/toxicidad , Polietileno/toxicidad , Ecotoxicología , Ecosistema , Contaminantes del Suelo/análisis , Suelo/química , Plaguicidas/farmacología
13.
Chem Asian J ; : e202400398, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775649

RESUMEN

Synthesis and photophysical properties of a fluorescent probe HBD is described. Probe upon interaction with metal ions, anions and nucleoside pyrophosphates (NPPs) showed fluorescence quenching with Cu2+ due to chelation enhanced quenching effect (CHEQ). Moreover, interaction of ensemble HBD.Cu2+ with anions and NPPs showed fluorescence "turn-On" response with ATP selectively. "On-Off-On" responses observed with Cu2+ and ATP is attributed to an interplay between ESIPT and TICT processes. Cyclic voltammogram of probe exhibited quasi-reversible redox behaviour with three oxidation and two reduction potentials and the change in band gaps of probe suggested the interaction with Cu2+ and ATP. The 2 : 1 and 1 : 1 binding stoichiometry for an interaction between probe and Cu2+ (LOD, 62 nM) and ensemble, HBD.Cu2+ with ATP (LOD, 0.4 µM) respectively are realised by Job's plot and HRMS data. Cell imaging studies carried out to detect Cu2+ and ATP in HeLa cells. Also, the output emission observed with Cu2+ and ATP is utilized to construct an implication (IMP) logic gate. Test paper strips showed naked-eye visible color responses to detect Cu2+ and ATP. In real water samples probe successfully detected copper (0.03 µM) between 5-6.5 ppb level (ICP-MS method).

14.
Anal Methods ; 16(19): 3131-3141, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38712986

RESUMEN

Plastics are ubiquitous in today's lifestyle, and their indiscriminate use has led to the accumulation of plastic waste in landfills and oceans. The waste accumulates and breaks into micro-particles that enter the food chain, causing severe threats to human health, wildlife, and the ecosystem. Environment-friendly and bio-based degradable materials offer a sustainable alternative to the vastly used synthetic materials. Here, a polylactic acid and carbon nanofiber-based membrane and a paper-based colorimetric sensor have been developed. The membrane had a surface area of 3.02 m2 g-1 and a pore size of 18.77 nm. The pores were evenly distributed with a pore volume of 0.0137 cm3 g-1. The membrane was evaluated in accordance with OECD guidelines and was found to be safe for tested aquatic and terrestrial models. The activated PLA-CNF membrane was further used as a bio-based electrode for the electrochemical detection of nitrates (NO3-) in water samples with a detection limit of 0.046 ppm and sensitivity of 1.69 × 10-4 A ppm-1 mm-2, whereas the developed paper-based colorimetric sensor had a detection limit of 156 ppm for NO3-. This study presents an environment-friendly, low-carbon footprint disposable material for sensing applications as a sustainable alternative to plastics.


Asunto(s)
Carbono , Colorimetría , Nanofibras , Nitratos , Papel , Poliésteres , Nanofibras/química , Colorimetría/métodos , Colorimetría/instrumentación , Nitratos/análisis , Nitratos/química , Poliésteres/química , Carbono/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Límite de Detección , Contaminantes Químicos del Agua/análisis , Conductividad Eléctrica , Membranas Artificiales
15.
Mol Neurobiol ; 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38353925

RESUMEN

Demyelination is the loss of myelin in CNS, resulting in damaged myelin sheath. Oxidative stress and neuroinflammation play a key role in inducing demyelinating diseases like MS; hence, controlling oxidative stress and neuroinflammation is important. Cuprizone (CPZ), a copper chelator, generates oxidative stress and neuroinflammation, thereby inducing demyelination. Therefore, the CPZ-induced demyelinating mouse model (CPZ model) is widely used in research. The present study was intended to unravel a mechanism of inhibition of demyelination by arsenic in a CPZ model, which is otherwise known for its toxicity. We investigated an alternative mechanism of inhibition of demyelination by arsenic through the reversal of SOD1 activity employing in silico analysis, analytical chemistry techniques, and in vitro and in vivo experiments. In vivo experiments showed protection of body weight, survivability, and myelination of the corpus callosum in CPZ and arsenic-co-exposed animals, where neuroinflammation was apparently not involved. In vitro experiments revealed that arsenic-mediated reversal of impaired SOD1 activity leads to reduced cellular ROS levels and better viability of primary oligodendrocytes. Reversal of SOD1 activity was also observed in the corpus callosum tissue isolated from experimental animals. In silico and analytical chemistry studies revealed that similar to copper, arsenic can potentially bind to CPZ and thereby make the copper freely available for SOD1 activity. Suitable neurobehavior tests further validated the protective effect of arsenic. Taken together, the present study revealed that arsenic protects oligodendrocytes and demyelination of corpus callosum by reversing CPZ-induced impaired SOD1 activity.

16.
ACS Appl Mater Interfaces ; 15(16): 19904-19920, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37046174

RESUMEN

Combining antiangiogenic and chemotherapeutic agents has shown promising clinical benefits in cancer cures when the therapeutic intervention takes into account the tissue and molecular targets. Moreover, the risk of induced drug resistance is minimized when multiple pathways are involved in the treatment regimen, yielding a better therapeutic outcome. Nanodrug delivery systems have proven to be a prudent approach to treating complex disease pathologies. As such, combining antiangiogenic and chemotherapeutic drugs within multimodal nanocarriers synergistically augments the clinical efficiency of the drugs. This study reports the combinatorial efficacy of heparin (Hep), selenium NPs (SeNPs), and doxorubicin (Dox) to inhibit tumor growth and progression. Both Se@Hep-NPs and Se@Hep-Dox-NPs with excellent water dispersity having a size and charge in the range of 250 ± 5 and 253 ± 5 nm and -53 ± 0.4 and -48.4 ± 6.4 mV, respectively, showed strong anticancer potential assessed through in vitro assays like cell viability, specificity, colony formation, and wound scratch in MCF7 cells. Strong synergistic interactions among SeNPs, Hep, and Dox in Se@Hep-Dox-NPs render it to be an antiangiogenic and proapoptotic cancer cell death inducers. In vivo imaging highlights the dual-mode attributes of Se@Hep-NPs with desirable passive tumor targeting and biomedical imaging ability when tagged with Cy7.5, while Se@Hep-Dox-NPs significantly reduce the tumor burden and prolong the longevity of subcutaneous EAC-bearing mice. Histopathology studies reveal no signs of toxicity in major organs. Collectively, these results qualify Se@Hep-Dox-NPs as a plausible clinical therapeutic candidate.


Asunto(s)
Antineoplásicos , Nanopartículas , Selenio , Animales , Ratones , Selenio/farmacología , Inhibidores de la Angiogénesis/farmacología , Inhibidores de la Angiogénesis/uso terapéutico , Apoptosis , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Sistemas de Liberación de Medicamentos/métodos , Antineoplásicos/farmacología , Heparina/farmacología , Nanopartículas/uso terapéutico , Línea Celular Tumoral
17.
Carbohydr Polym ; 302: 120368, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36604048

RESUMEN

The rapidly growing electronic and plastic waste has become a global environmental concern. Developing advanced and environmentally safe agro-based materials is an emerging field with an enormous potential for applications in sensors and devices. Here, an agro-based material as membrane has been developed by incorporating tapioca starch and banana peel powder in polylactic acid, with uniform dispersibility and amorphous nature. The material was used for the development of electrochemical sensor for S-gene of SARS-CoV-2. Further, the membrane was used for the development of a non-invasive, colorimetric skin patch for the detection of glucose and a sensor for the assessment of fruit juice quality. Using OECD-recommended model systems, the developed membrane was found to be non-toxic towards aquatic and terrestrial non-target organisms. The developed conductive material opens new avenues in various electrochemical, analytical, and biological applications.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Manihot , Musa , Musa/química , Colorimetría , COVID-19/diagnóstico , SARS-CoV-2 , Almidón/química
18.
Food Chem ; 418: 135965, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37018903

RESUMEN

Bioelectrodes with low carbon footprint can provide an innovative solution to the surmounting levels of e-waste. Biodegradable polymers offer green and sustainable alternatives to synthetic materials. Here, a chitosan-carbon nanofiber (CNF) based membrane has been developed and functionalized for electrochemical sensing application. The surface characterization of the membrane revealed crystalline structure with uniform particle distribution, and surface area of 25.52 m2/g and pore volume of 0.0233 cm3/g. The membrane was functionalized to develop a bioelectrode for the detection of exogenous oxytocin in milk. Electrochemical impedance spectroscopy was employed to determine oxytocin in a linear concentration range of 10 to 105 ng/mL. The developed bioelectrode showed an LOD of 24.98 ± 11.37 pg/mL and sensitivity of 2.77 × 10-10 Ω / log ng mL-1/mm2 for oxytocin in milk samples with 90.85-113.34 percent recovery. The chitosan-CNF membrane is ecologically safe and opens new avenues for environment-friendly disposable materials for sensing applications.


Asunto(s)
Técnicas Biosensibles , Quitosano , Nanofibras , Carbono/química , Quitosano/química , Oxitocina/química , Electrodos , Técnicas Biosensibles/métodos
19.
Bioconjug Chem ; 23(3): 664-70, 2012 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-22369664

RESUMEN

An engineered polymer support 5 has been prepared for the solid-phase assembly of 3'-carboxyalkyl-modified oligonucleotides using commonly available reagents. A two-step deprotection procedure resulted in the quantitative cleavage of oligonucleotides from the support and removal of the protecting groups from phosphodiesters and exocyclic amino groups of the nucleic bases. The fully deprotected oligomers, obtained in high yield, were desalted and analyzed on RP-HPLC. After characterization by MALDI-TOF, these carboxyalkylated oligonucleotides were immobilized onto the epoxy-functionalized glass microslides to prepare biochips. The performance of these biochips was evaluated under different sets of conditions and then successfully validated by the detection of base mismatches and human infectious disease, bacterial meningitis, caused by N. meningitidis.


Asunto(s)
Oligonucleótidos/química , Polímeros/química , Análisis por Matrices de Proteínas , Cromatografía Líquida de Alta Presión , Humanos , Reacción en Cadena de la Polimerasa , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
20.
Biomater Adv ; 133: 112633, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35527136

RESUMEN

Ability of the cells to adhere to an extracellular material is central to successful tissue genesis. Arg-Gly-Asp (RGD) sequences found in extracellular matrix proteins are well known for cell adhesion, however, enzymatic degradation and lack of specificity have limited their widespread use. Besides, a multifunctional material with inherent antimicrobial ability would help in invigorating the practical tissue engineering applications. Here, we report novel modified RGD (MR) and RGD mimic [R(K)] peptides (MOH and MNH2) which were synthesized post-in-silico screening, based on their interactions with integrin protein αVß3 using HEX 8.0 docking server. These mimics, containing hydrophobic Phe-Phe (FF) moiety which has been specifically introduced to initiate the self-assembling process of ß-sheet structures, were characterized thoroughly using various physicochemical and spectroscopic techniques. Under physiological conditions, these mimetics displayed thixotropic behavior rendering them highly suitable as injectable hydrogels having an added advantage of site-specific targeting abilities. Electron microscopy further revealed the formation of nanofibers upon self-assembly of these peptides. Besides, enhanced cell adhesiveness by these peptides compared to the commercial Poly l-lysine coated surfaces as well as the inherent antimicrobial potential against both sensitive and antibiotic-resistant pathogens (Methicillin-resistant Staphylococcus aureus and multi-drug resistant Salmonella enteritidis) substantiated the applicability of these unique injectable hydrogels wherein the porous fibrous framework offered a favorable environment for drug entrapment and 3D cell culture. Altogether, these properties render these novel RGD mimic peptides as promising multifunctional candidates for various tissue regenerative applications.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Peptidomiméticos , Materiales Biocompatibles , Hidrogeles/química , Oligopéptidos/farmacología , Péptidos/química , Peptidomiméticos/farmacología , Conformación Proteica en Lámina beta
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