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1.
J Phys Chem Lett ; 15(19): 5295-5305, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38722703

RESUMO

Coacervate microdroplets, a protocell model in exploring the origin of life, have gained significant attention. Clay minerals, catalysts during the origin of life, are crucial in the chemical evolution of small molecules into biopolymers. However, our understanding of the relationship between clay minerals and the formation and evolution of protocells on early Earth remains limited. In this work, the nanoclay montmorillonite nanosheet (MMT-Na) was employed to investigate its interaction with coacervate microdroplets formed by oligolysine (K10) and adenine nucleoside triphosphate (ATP). As an anionic component, MMT-Na was noted to promote the formation of coacervate microdroplets. Furthermore, the efficiency of ssDNA enrichment and the degree of ssDNA hybridization within these microdroplets were significantly improved. By combining inorganic nanoclay with organic biopolymers, our work provides an efficient way to enrich genetic biomolecules in the primitive Earth environment and builds a nanoclay-based coacervate microdroplets, shedding new light on life's origin and protocell evolution.


Assuntos
Células Artificiais , Bentonita , Células Artificiais/química , Bentonita/química , DNA de Cadeia Simples/química , Argila/química , Trifosfato de Adenosina/química , Nanoestruturas/química , Origem da Vida , Hibridização de Ácido Nucleico
2.
Int J Pharm ; 656: 124073, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38569977

RESUMO

Traumatic multidrug-resistant bacterial infections are the most threat to wound healing. Lower extremity wounds under diabetic conditions display a significant delay during the healing process. To overcome these challenges, the utilization of protein-based nanocomposite dressings is crucial in implementing a successful regenerative medicine approach. These dressings hold significant potential as polymer scaffolds, allowing them to mimic the properties of the extracellular matrix (ECM). So, the objective of this study was to develop a nanocomposite film using dialdehyde-xanthan gum/soy protein isolate incorporated with propolis (PP) and halloysite nanotubes (HNTs) (DXG-SPI/PP/HNTs). In this protein-polysaccharide hybrid system, the self-healing capability was demonstrated through Schiff bonds, providing a favorable environment for cell encapsulation in the field of tissue engineering. To improve the properties of the DXG-SPI film, the incorporation of polyphenols found in PP, particularly flavonoids, is proposed. The synthesized films were subjected to investigations regarding degradation, degree of swelling, and mechanical characteristics. Additionally, halloysite nanotubes (HNTs) were introduced into the DXG-SPI/PP nanocomposite films as a reinforcing filler with varying concentrations of 3 %, 5 %, and 7 % by weight. The scanning electron microscope (SEM) analysis confirmed the proper embedding and dispersion of HNTs onto the DXG-SPI/PP nanocomposite films, leading to functional interfacial interactions. The structure and crystallinity of the synthesized nanocomposite films were characterized using Fourier Transform Infrared Spectrometry (FTIR) and X-ray diffraction (XRD), respectively. Moreover, the developed DXG-SPI/PP/HNTs nanocomposite films significantly improved cell growth of NIH-3T3 fibroblast cells in the presence of PP and HNTs, indicating their cytocompatibility. The antibacterial activity of the nanocomposite was evaluated against Escherichia coli (E. Coli) and Staphylococcus aureus (S. Aureus), which are commonly associated with wound infections. Overall, our findings suggest that the synthesis of DXG-SPI/PP/HNTs nanocomposite scaffolds holds great promise as a clinically relevant biomaterial and exhibits strong potential for numerous challenging biomedical applications.


Assuntos
Antibacterianos , Antioxidantes , Argila , Nanocompostos , Nanotubos , Polissacarídeos Bacterianos , Própole , Proteínas de Soja , Cicatrização , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Nanotubos/química , Argila/química , Cicatrização/efeitos dos fármacos , Animais , Própole/química , Própole/farmacologia , Própole/administração & dosagem , Polissacarídeos Bacterianos/química , Camundongos , Proteínas de Soja/química , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/administração & dosagem , Nanocompostos/química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos
3.
Environ Sci Pollut Res Int ; 31(20): 29357-29373, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38573574

RESUMO

In this study, Tunisian raw clay (RC) was utilized as a cheap source of silicium and aluminum for the preparation of faujasite zeolite (FAUsyn) using the alkaline fusion technique. The zeolite's structural analysis was carried out using the XRD, nitrogen adsorption-desorption, and SEM-EDX techniques. The data collected demonstrate that the produced zeolite only included one homogeneous faujasite phase. Textural analysis shows that the FAUsyn prepared from RC has a hierarchical porosity (micro-, meso-, and macropores). The total porosity was found to be 0.33 cm3/g as well as the BET area was equal to 360 m2/g. Adsorption experiments for propene capture were performed using the FAUsyn as adsorbent material. The performance of the column was examined in relation to various parameter impacts, including flow rate (50, 100, and 150 mL/min), input concentration (4, 8, and 12 mg/L), and bed depth (10, 14, and 18 cm). Finally, experimental and theoretical studies were investigated to predict adsorption capacities and kinetics parameters. To clarify and estimate column inputs, a model that incorporates axial dispersion, Langmuir equation, and migration within the adsorbent's pore was improved. COMSOL Multiphysics software was used to execute the model and resolve it computationally. The results of the experiments and the expected breakthrough curves were very well agreed. Modeling obtained results can be extrapolated to industrial level.


Assuntos
Argila , Zeolitas , Zeolitas/química , Adsorção , Argila/química , Tunísia , Cinética , Porosidade
4.
Int J Biol Macromol ; 265(Pt 1): 130894, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38490388

RESUMO

Bamboo fibers (BF), as an important sustainable natural material, are becoming a hot alternative to synthetic fibers for the reinforcement of polypropylene (PP)-based composites. However, the weak interfacial compatibility between BF and PP as matrix and their inherent flammability limit the practical application of BF/PP composites (BPC). Here, a fire-safe BPC was fabricated by constructing flame-retardant interfacial layers containing tannic acid (TA)-Fe3+ complex and halloysite nanotubes (HNTs) on the fiber matrix followed by a hot-pressing process. The results showed that the interfacial chelating of TA with Fe3+ improved the dispersion of HNTs on the fibers and the interfacial interactions within the fiber matrix, resulting in the as-fabricated composite with significantly improved mechanical properties and water resistance. In addition, the flame-retardant composite exhibited higher thermal stability and enhanced residual char content. Moreover, the composite possessed significant flame-retardant performances with a reduction of 23.75 % in the total heat release and 32.44 % in the total smoke production, respectively, owing to the flame retarding in gaseous phase and condensed phase of TA-Fe3+@HNTs layers. This work offers a green and eco-friendly strategy to address the inherent problems of BPC material in terms of fire safety and interfacial compatibility, thus broadening their applications in the automotive interior and construction industries.


Assuntos
Indústria da Construção , Retardadores de Chama , Nanotubos , Polifenóis , Argila , Polipropilenos
5.
Sci Total Environ ; 926: 171809, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38513845

RESUMO

Soil cadmium (Cd) can affect crop growth and food safety, and through the enrichment in the food chain, it ultimately poses a risk to human health. Reducing the re-mobilization of Cd caused by the release of protons and acids by crops and microorganisms after stabilization is one of the significant technical challenges in agricultural activities. This study aimed to investigate the re-mobilization of stabilized Cd within the clay mineral-bound fraction of soil and its subsequent accumulation in crops utilizing nitrogen ammonium nitrogen (NH4+-N) and nitrate nitrogen (NO3--N), at 60 and 120 mg kg-1. Furthermore, the study harvested root exudates at various growth stages to assess their direct influence on the re-mobilization of stabilized Cd and to evaluate the indirect effects mediated by soil microorganisms. The results revealed that, in contrast to the NO3--N treatment, the NH4+-N treatment significantly enhanced the conversion of clay mineral-bound Cd in the soil to NH4NO3-extractable Cd. It also amplified the accumulation of Cd in edible amaranth, with concentrations in roots and shoots rising from 1.7-6.0 mg kg-1 to 4.3-9.8 mg kg-1. The introduction of NH4+-N caused a decrease in the pH value of the rhizosphere soil and stimulated the production and secretion organic and amino acids, such as oxalic acid, lactic acid, stearic acid, succinic acid, and l-serine, from the crop roots. Furthermore, compared to NO3--N, the combined interaction of root exudates with NH4+-N has a more pronounced impact on the abundance of microbial genes associated with glycolysis pathway and tricarboxylic acid cycle, such as pkfA, pfkB, sucB, sucC, and sucD. The effects of NH4+-N on crops and microorganisms ultimately result in a significant increase in the re-mobilization of stabilized Cd. However, the simulated experiments showed that microorganisms only contribute to 3.8-6.6 % of the re-mobilization of clay mineral-bound Cd in soil. Therefore, the fundamental strategy to inhibit the re-mobilization of stabilized Cd in vegetable cultivation involves the regulation of proton and organic acid secretion by crops.


Assuntos
Poluentes do Solo , Solo , Humanos , Solo/química , Cádmio/análise , Argila , Nitrogênio/metabolismo , Compostos Orgânicos/metabolismo , Produtos Agrícolas/metabolismo , Minerais/metabolismo , Fertilização , Poluentes do Solo/análise
6.
Environ Geochem Health ; 46(4): 132, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483701

RESUMO

We determined the distribution, fate, and health hazards of dimethenamid-P, metazachlor, and pyroxasulfone, the effective pre-emergence herbicides widely used both in urban and agricultural settings globally. The rate-determining phase of sorption kinetics of these herbicides in five soils followed a pseudo-second-order model. Freundlich isotherm model indicated that the herbicides primarily partition into heterogeneous surface sites on clay minerals and organic matter (OM) and diffuse into soil micropores. Principal component analysis revealed that soil OM (R2, 0.47), sand (R2, 0.56), and Al oxides (R2, 0.33) positively correlated with the herbicide distribution coefficient (Kd), whereas clay (R2, ‒ 0.43), silt (R2, ‒ 0.51), Fe oxides (R2, ‒ 0.02), alkaline pH (R2, ‒ 0.57), and EC (R2, ‒ 0.03) showed a negative correlation with the Kd values. Decomposed OM rich in C=O and C-H functional groups enhanced herbicide sorption, while undecomposed/partially-decomposed OM facilitated desorption process. Also, the absence of hysteresis (H, 0.27‒0.88) indicated the enhanced propensity of herbicide desorption in soils. Leachability index (LIX, < 0.02-0.64) and groundwater ubiquity score (GUS, 0.02‒3.59) for the soils suggested low to moderate leaching potential of the herbicides to waterbodies, indicating their impact on water quality, nontarget organisms, and food safety. Hazard quotient and hazard index data for human adults and adolescents suggested that exposure to soils contaminated with herbicides via dermal contact, ingestion, and inhalation poses minimal to no non-carcinogenic risks. These insights can assist farmers in judicious use of herbicides and help the concerned regulatory authorities in monitoring the safety of human and environmental health.


Assuntos
Herbicidas , Poluentes do Solo , Humanos , Adolescente , Solo , Herbicidas/toxicidade , Herbicidas/análise , Argila , Fazendas , Poluentes do Solo/análise , Adsorção , Saúde Ambiental , Óxidos
7.
Environ Pollut ; 347: 123786, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484962

RESUMO

Water management in paddy soils can effectively reduce the soil-to-rice grain transfer of either As or Cd, but not of both elements simultaneously due to the higher mobility of As under reducing and Cd under oxidizing soil conditions. Limestone amendment, the common form of liming, is well known for decreasing Cd accumulation in rice grown on acidic soils. Sulfate amendment was suggested to effectively decrease As accumulation in rice, especially under intermittent soil flooding. To study the unknown effects of combined sulfate and limestone amendment under intermittent flooding for simultaneously decreasing As and Cd in rice, we performed a pot experiment using an acidic sandy loam paddy soil. We also included a clay loam paddy soil to study the role of soil texture in low-As rice production under intermittent flooding. We found that liming not only decreased rice Cd concentrations but also greatly decreased dimethylarsenate (DMA) accumulation in rice. We hypothesize that this is due to suppressed sulfate reduction, As methylation, and As thiolation by liming in the sulfate-amended soil and a higher share of deprotonated DMA at higher pH which is taken up less readily than protonated DMA. Decreased gene abundance of potential soil sulfate-reducers by liming further supported our hypothesis. Combined sulfate and limestone amendment to the acidic sandy loam soil produced rice with 43% lower inorganic As, 72% lower DMA, and 68% lower Cd compared to the control soil without amendment. A tradeoff between soil aeration and water availability was observed for the clay loam soil, suggesting difficulties to decrease As in rice while avoiding plant water stress under intermittent flooding in fine-textured soils. Our results suggest that combining sulfate amendment, liming, and intermittent flooding can help to secure rice safety when the presence of both As and Cd in coarse-textured soils is of concern.


Assuntos
Arsênio , Compostos de Cálcio , Oryza , Óxidos , Poluentes do Solo , Cádmio/análise , Arsênio/análise , Carbonato de Cálcio , Solo , Sulfatos , Argila , Óxidos de Enxofre , Areia , Poluentes do Solo/análise
8.
Nat Commun ; 15(1): 2020, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448477

RESUMO

Available evidences suggest that podoconiosis is triggered by long term exposure of bare feet to volcanic red clay soil particles. Previous genome-wide studies in Ethiopia showed association between the HLA class II region and disease susceptibility. However, functional relationships between the soil trigger, immunogenetic risk factors and the immunological basis of the disease are uncharted. Therefore, we aimed to characterise the immune profile and gene expression of podoconiosis patients relative to endemic healthy controls. Peripheral blood immunophenotyping of T cells indicated podoconiosis patients had significantly higher CD4 and CD8 T cell surface HLA-DR expression compared to healthy controls while CD62L expression was significantly lower. The levels of the activation markers CD40 and CD86 were significantly higher on monocytes and dendritic cell subsets in patients compared to the controls. RNA sequencing gene expression data indicated higher transcript levels for activation, scavenger receptors, and apoptosis markers while levels were lower for histones, T cell receptors, variable, and constant immunoglobulin chain in podoconiosis patients compared to healthy controls. Our finding provides evidence that podoconiosis is associated with high levels of immune activation and inflammation with over-expression of genes within the pro-inflammatory axis. This offers further support to a working hypothesis of podoconiosis as soil particle-driven, HLA-associated disease of immunopathogenic aetiology.


Assuntos
Elefantíase , Humanos , Elefantíase/genética , Histonas , Antígenos CD40 , Linfócitos T CD8-Positivos , Argila
9.
Chem Commun (Camb) ; 60(26): 3535-3538, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38450703

RESUMO

A Fe(III) intercalated montmorillonite nanoplatform (Fe-MMT) was engineered for doxorubicin (DOX) loading. The constructed Fe-MMT/DOX nanoplatform could not only improve the production of H2O2 to enhance chemodynamic therapy but interfere with DNA damage repair to amplify the efficacy of DOX, proving an ideal combination of chemotherapy and chemodynamic therapy.


Assuntos
Compostos Férricos , Neoplasias , Humanos , Argila , Peróxido de Hidrogênio , Doxorrubicina/farmacologia , Linhagem Celular Tumoral
10.
J Colloid Interface Sci ; 663: 9-20, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38387188

RESUMO

Peptide nucleic acid (PNA) is a DNA mimic that shows good stability against nucleases and proteases, forming strongly recognized complementary strands of DNA and RNA. However, due to its feeble ability to cross the cellular membrane, PNA activity and its targeting gene action is limited. Halloysite nanotubes (HNTs) are a natural and low-cost aluminosilicate clay. Because of their peculiar ability to cross cellular membrane, HNTs represent a valuable candidate for delivering genetic materials into cells. Herein, two differently charged 12-mer PNAs capable of recognizing as molecular target a 12-mer DNA molecule mimicking a purine-rich tract of neuroglobin were synthetized and loaded onto HNTs by electrostatic attraction interactions. After characterization, the kinetic release was also assessed in media mimicking physiological conditions. Resonance light scattering measurements assessed their ability to bind complementary single-stranded DNA. Furthermore, their intracellular delivery was assessed by confocal laser scanning microscopy on living MCF-7 cells incubated with fluorescence isothiocyanate (FITC)-PNA and HNTs labeled with a probe. The nanomaterials were found to cross cellular membrane and cell nuclei efficiently. Finally, it is worth mentioning that the HNTs/PNA can reduce the level of neuroglobin gene expression, as shown by reverse transcription-quantitative polymerase chain reaction and western blotting analysis.


Assuntos
DNA , Nanotubos , Argila , Neuroglobina , RNA Mensageiro/genética , Nanotubos/química
11.
Environ Geochem Health ; 46(3): 71, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38366045

RESUMO

Inorganic arsenic (iAs) is a carcinogen. Vegetables such as water spinach (Ipomoea aquatica Forssk.) and amaranth (Amaranthus mangostanus L.) are recognized as high-risk sources of iAs exposure because they can accumulate significant amounts of iAs and are widely consumed. To ensure safe cultivation conditions, this study aimed to establish prediction models for iAs concentration in the edible parts of water spinach and amaranth based on soil properties. Subsequently, health risk assessments associated with iAs exposure through the consumption of these vegetables were conducted using prediction models. Soil samples were collected from agricultural fields in Taiwan and used in the pot experiments. Pearson correlation and partial correlation analyses were used to explore the relationship between soil properties, including total As, clay, organic matter, iron oxides and available phosphates, and iAs concentration in edible parts of water spinach and amaranth. Prediction models based on soil properties were developed by stepwise multiple linear regression. Health risk assessments were conducted using the Monte Carlo algorithm. The results indicate that total As and organic matter contents in soil were major predictors of iAs concentration in water spinach, whereas those in amaranth were total As and clay contents. Therefore, higher health risks for consuming water spinach and amaranth are associated with higher levels of organic matter and clay contents in soil, respectively, and these are crucial factors to consider to ensure food safety. This study suggested that As-elevated soils enriched with organic matter and clay contents should be avoided when growing water spinach and amaranth, respectively.


Assuntos
Amaranthus , Arsênio , Poluentes do Solo , Verduras , Solo , Arsênio/toxicidade , Arsênio/análise , Argila , Inocuidade dos Alimentos , Poluentes do Solo/toxicidade , Poluentes do Solo/análise
12.
Colloids Surf B Biointerfaces ; 235: 113768, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325142

RESUMO

Cancer is still one of the deadliest diseases, and diagnosing and treating it effectively remains difficult. As a result, advancements in earlier detection and better therapies are urgently needed. Conventional chemotherapy induces chemoresistance, has non-specific toxicity, and has a meager efficacy. Natural materials like nanosized clay mineral formations of various shapes (platy, tubular, spherical, and fibrous) with tunable physicochemical, morphological, and structural features serve as potential templates for these. As multifunctional biocompatible nanocarriers with numerous applications in cancer research, diagnosis, and therapy, their submicron size, individual morphology, high specific surface area, enhanced adsorption ability, cation exchange capacity, and multilayered organization of 0.7-1 nm thick single sheets have attracted significant interest. Kaolinite, halloysite, montmorillonite, laponite, bentonite, sepiolite, palygorskite, and allophane are the most typical nanoclay minerals explored for cancer. These multilayered minerals can function as nanocarriers to effectively carry a variety of anticancer medications to the tumor site and improve their stability, dispersibility, sustained release, and transport. Proteins and DNA/RNA can be transported using nanoclays with positive and negative surfaces. The platform for phototherapeutic agents can be nanoclays. Clays with bio-functionality have been developed using various surface engineering techniques, which could help treat cancer. The promise of nanoclays as distinctive crystalline materials with applications in cancer research, diagnostics, and therapy are examined in this review.


Assuntos
Bentonita , Neoplasias , Humanos , Bentonita/química , Caulim , Argila , Minerais , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico
13.
BMC Pregnancy Childbirth ; 24(1): 39, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182997

RESUMO

BACKGROUND: Anaemia during pregnancy causes adverse outcomes to the woman and the foetus, including anaemic heart failure, prematurity, and intrauterine growth restriction. Iron deficiency anaemia (IDA) is the leading cause of anaemia and oral iron supplementation during pregnancy is widely recommended. However, little focus is directed to dietary intake. This study estimates the contribution of IDA among pregnant women and examines its risk factors (including dietary) in those with moderate or severe IDA in Lagos and Kano states, Nigeria. METHODS: In this cross-sectional study, 11,582 women were screened for anaemia at 20-32 weeks gestation. The 872 who had moderate or severe anaemia (haemoglobin concentration < 10 g/dL) were included in this study. Iron deficiency was defined as serum ferritin level < 30 ng/mL. We described the sociodemographic and obstetric characteristics of the sample and their self-report of consumption of common food items. We conducted bivariate and multivariable logistic regression analysis to identify risk factors associated with IDA. RESULTS: Iron deficiency was observed among 41% (95%CI: 38 - 45) of women with moderate or severe anaemia and the prevalence increased with gestational age. The odds for IDA reduces from aOR: 0.36 (95%CI: 0.13 - 0.98) among pregnant women who consume green leafy vegetables every 2-3 weeks, to 0.26 (95%CI: 0.09 - 0.73) among daily consumers, compared to those who do not eat it. Daily consumption of edible kaolin clay was associated with increased odds of having IDA compared to non-consumption, aOR 9.13 (95%CI: 3.27 - 25.48). Consumption of soybeans three to four times a week was associated with higher odds of IDA compared to non-consumption, aOR: 1.78 (95%CI: 1.12 - 2.82). CONCLUSION: About 4 in 10 women with moderate or severe anaemia during pregnancy had IDA. Our study provides evidence for the protective effect of green leafy vegetables against IDA while self-reported consumption of edible kaolin clay and soybeans appeared to increase the odds of having IDA during pregnancy. Health education on diet during pregnancy needs to be strengthened since this could potentially increase awareness and change behaviours that could reduce IDA among pregnant women with moderate or severe anaemia in Nigeria and other countries.


Assuntos
Anemia , Deficiências de Ferro , Gravidez , Feminino , Humanos , Estudos Transversais , Nigéria/epidemiologia , Gestantes , Prevalência , Argila , Caulim , Ferro , Anemia/epidemiologia , Fatores de Risco
14.
Environ Monit Assess ; 196(2): 125, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195960

RESUMO

This study aims to optimize the QuEChERS methodology for extracting three pesticides (fipronil, thiobencarb, and cartap) from two paddy soils with distinct characteristics. Various modifications were explored to enhance extraction efficiency, employing acetonitrile (MeCN) or ethyl acetate (EtOAc) for extraction and primary-secondary amine (PSA) and graphitized carbon black (GCB) for the clean-up. Assessment criteria included accuracy, precision, linearity, detection limits, uncertainty, and matrix effects. Results revealed that the clayey soil with lower organic carbon (OC) content (1.26%) and 100% moisture yielded the highest pesticide recoveries (113.72%, 115.73%, and 116.41% for FIP, THIO, and CART, respectively). In contrast, the silty clayey soil with higher OC content (2.91%) and 20% water content exhibited poor recoveries (< 60%). FIP and CART demonstrated better recoveries with MeCN, while THIO performed better with EtOAc under specific moisture conditions. Clean-up sorbents significantly reduced FIP and CART recoveries, with THIO recoveries less affected. Acidifying with HCl substantially improved CART recovery. EtOAc introduced a moderate to strong matrix effect for FIP and THIO, while MeCN in soils with 100% moisture resulted in a strong matrix effect for CART. The study highlighted the substantial impact of extraction conditions, pesticide properties, and soil conditions on the outcomes of the QuEChERS method. A comprehensive understanding of these interplays was deemed crucial for accurately quantifying pesticide residues in agricultural soils.


Assuntos
Praguicidas , Solo , Monitoramento Ambiental , Argila , Carbono
15.
Clin Oral Investig ; 28(1): 68, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38165480

RESUMO

AIMS AND OBJECTIVE: Presurgical infant's orthopedic appliances (PSIOs) play an increasingly crucial role in the interdisciplinary management of neonatal CLP, aiming to improve and maintain adequate nasolabial aesthetics, followed by primary lip/nasal surgery in both unilateral and bilateral CLP cases. The use of PSIOs in cleft lip and palate patients can lead to contamination with oral microflora, acting as a potential reservoir for infectious microorganisms. Acrylic surfaces might provide retention niches for microorganisms to adhere, and inhabit, which is difficult to control in immunocompromised patients, thus predisposing them to increased infection risks. The objective of this multi-assay in vitro study was to investigate the effects of incorporating chlorhexidine-loaded halloysite nanotubes (CHX-HNTs) fillers on the morphological, cytotoxic, release, and antimicrobial characteristics of self-cured acrylic polymethyl methacrylate (PMMA) material used in pre-surgical orthopedic appliances. METHODS: Disk-shaped PMMA specimens were prepared with varying proportions of CHX-HNTs. A control group without any addition served as a reference, and four experimental samples contained a range of different concentrations of CHX-HNTs (1.0, 1.5, 3, and 4.5 wt%). The antimicrobial efficacy was assessed using an agar diffusion test against common reference microorganisms: Candida albicans, Staphylococcus aureus, Streptococcus pneumoniae, and Streptococcus agalactiae. Cytotoxicity was examined using the L929 cell line (mouse fibroblasts) through a (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide, MTT) cell viability assay. The release kinetics of CHX were monitored using UV-spectral measurements. The statistical analysis used a one-way ANOVA followed by Tukey's post hoc test. RESULTS: The integration of CHX-HNTs in PMMA exhibited a substantial dose-dependent antifungal and antibacterial effect against microorganisms at tested mass fractions (1.0 to 4.5 wt%). CHX release was sustained for up to 60 days, supporting prolonged antimicrobial activity. Furthermore, no significant cytotoxicity was determined in the L929 fibroblast cell line (control), indicating the biocompatibility of the CHX-HNTs-enhanced PMMA. CONCLUSION: Incorporating CHX-HNTs in PMMA successfully enhanced its antimicrobial properties, providing sustained CHX release and superior antimicrobial efficacy. These findings demonstrate the potential of antimicrobial nanoparticles in dental therapies to improve therapeutic outcomes. However, rigorous further clinical trials and observational studies are warranted to validate the practical application, safety, and efficacy. CLINICAL RELEVANCE: This study has the potential to make a major impact on the health of infants born with cleft lip and palate by helping to reduce the prevalence of infectious illnesses. The incorporation of CHX-HNTs into PMMA-based appliances is a novel promising preventive approach to reduce microbial infections.


Assuntos
Anti-Infecciosos , Fenda Labial , Fissura Palatina , Lactente , Animais , Camundongos , Recém-Nascido , Humanos , Clorexidina/farmacologia , Argila , Polimetil Metacrilato , Estética Dentária
16.
Curr Drug Deliv ; 21(5): 645-661, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37038294

RESUMO

Clay materials are widely used in drug delivery systems due to their unique characteristics. Montmorillonite is a major component of bentonite and it has a large surface area, better swelling capacity, and high adsorption capacity. The modification of natural bentonite could improve its sorption ability for new emerging applications. Recent advancements in the polymer-silicate composite have novel biomedical applications in drug delivery, tissue regeneration, wound healing, cancer therapy, enzyme immobilization, diagnostic and therapeutic devices, etc. Perspective view of the montmorillonite- polymer composite as a pharmaceutical carrier in drug delivery systems has been discussed in this review. Different types of modification of montmorillonite for the development of pharmaceutical formulations have also been documented. Many challenges in clay nanocomposite systems of polymer of natural/synthetic origin are yet to be explored in improving antimicrobial properties, mechanical strength, stimuli responsiveness, resistance to hydrolysis, etc. Drug interaction and binding capability, swelling of clay may be carried out for finding possible applications in monitoring delivery systems. Pharmaceutical properties of active drugs in the formulation could also be improved along with dissolution rate, solubility, and adsorption. The clay-incorporated polymeric drug delivery systems may be examined for a possible increase in swelling capacity and residence time after mucosal administration.


Assuntos
Bentonita , Polímeros , Argila , Bentonita/química , Sistemas de Liberação de Medicamentos , Preparações Farmacêuticas
17.
Adv Mater ; 36(9): e2309562, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939375

RESUMO

Ferroptosis-triggered immunogenic cell death (ICD) is widely adopted to potentiate the body's antitumor immunity by catalyzing the production of toxic reactive oxygen species (ROS). However, the efficacy of ferroptosis and immunotherapy is greatly restricted by intracellular abundant glutathione (GSH) and immunosuppressive tumor microenvironment (TME). Herein, a facile bottom-up method for solvent-free synthesis of ultrathin manganese (Mn)-based layered double hydroxide nanosheets with high loading efficiency for pro-inflammatory cytokine interferon (IFNγ) (IFNγ/uMn-LDHs) is proposed to mutually reinforce the ferroptosis and systemic immunity. The introduction of manganese ions significantly contributes to GSH depletion and hydroxyl radical generation, which can be further enhanced by IFNγ delivery-induced SLC7A11 downregulation. The ICD effect after cell ferroptosis cooperates with the intrinsic immunomodulatory property of IFNγ/uMn-LDHs to facilitate the maturation of dendritic cells (DCs) and the priming of T cells. IFNγ secretion from activated CD8+ T cells in turn involves cascade immunogenic ferroptosis, thus constructing a closed-loop therapy. Remarkably, a potent abscopal effect is observed in the growth inhibition of both primary and distant tumors. Overall, the ultrathin Mn-based clay nanoplatform provides a simple approach for mutual regulation between ferroptosis and antitumor immune response, overcoming the obstacles of current cancer immunotherapy.


Assuntos
Ferroptose , Neoplasias , Argila , Linfócitos T CD8-Positivos , Manganês , Imunoterapia , Glutationa , Neoplasias/terapia
18.
Immunopharmacol Immunotoxicol ; 46(2): 199-211, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38151925

RESUMO

CONTEXT: Aflatoxins are the most harmful mycotoxins that cause human and animal health concerns. Aflatoxin M1 (AFM1) is the primary hydroxylated metabolite of aflatoxin B1 and is linked to the development of hepatocellular carcinoma and immunotoxicity in humans and animals. Because of the important role of dairy products in human life, especially children, AFM1 is such a major concern to humans because of its frequent occurrence in dairy products at concentrations high enough to cause adverse effects to human and animal health. Reduced its bioavailability becomes a high priority in order to protect human and animal health. OBJECTIVES: This study aimed to investigate, in vivo, the ability of lactic acid bacteria (lactobacillus rhamnosus GAF01, LR) and clay mineral (bentonite, BT) mixture to mitigate/reduce AFM1-induced immunotoxicity, hepatotoxicity, nephrotoxicity and oxidative stress in exposed Balb/c mice. MATERIALS AND METHODS: The in vivo study was conducted using male Balb/c mice that treated, orally, by AFM1 alone or in combination with LR and/or BT, daily for 10 days as follows: group 1 control received 200 µl of PBS, group 2 treated with LR alone (2.108 CFU/mL), group 3 treated with BT alone (1 g/kg bw), group 4 treated with AFM1 alone (100 µg/kg), group 5 co-treated with LR + AFM1, group 6 co-treated with BT + AFM1, group 7 co-treated with BT + LR + AFM1. Forty-eight h after the end of the treatment, the mice were sacrificed and the blood, spleen, thymus, liver and kidney were collected. The blood was used for biochemical and immunological study. Spleen and thymus samples were used to thymocytes and splenocytes assessments. Liver and kidney samples were the target for evaluation of oxidative stress enzymes status and for histological assays. RESULTS: The results showed that AFM1 caused toxicities in male Blab/c mice at different levels. Treatment with AFM1 resulted in severe stress of liver and kidney organs indicated by a significant change in the biochemical and immunological parameters, histopathology as well as a disorder in the profile of oxidative stress enzymes levels. Also, it was demonstrated that AFM1 caused toxicities in thymus and spleen organs. The co-treatment with LR and/or BT significantly improved the hepatic and renal tissues, regulated antioxidant enzyme activities, spleen and thymus viability and biochemical and immunological parameters. LR and BT alone showed to be safe during the treatment. CONCLUSION: In summary, the LR and/or BT was able to reduce the biochemical, histopathological and immunological damages induced by AFM1 and indeed it could be exploited as one of the biological strategies for food and feedstuffs detoxification.


Assuntos
Lactobacillales , Humanos , Criança , Masculino , Camundongos , Animais , Lactobacillales/metabolismo , Argila , Camundongos Endogâmicos BALB C , Aflatoxina M1/toxicidade , Aflatoxina M1/metabolismo , Aflatoxina B1/toxicidade , Minerais/toxicidade , Contaminação de Alimentos
19.
Mar Pollut Bull ; 199: 115919, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134872

RESUMO

Marine oil spills have devastating environmental impacts and extrapolation of experimental fate and impact data from the lab to the field remains challenging due to the lack of comparable field data. In this work we compared two field systems used to study in situ oil depletion with emphasis on biodegradation and associated microbial communities. The systems were based on (i) oil impregnated clay beads and (ii) hydrophobic Fluortex adsorbents coated with thin oil films. The bacterial communities associated with the two systems displayed similar compositions of dominant bacterial taxa. Initial abundances of Oceanospirillales were observed in both systems with later emergences of Flavobacteriales, Alteromonadales and Rhodobacterales. Depletion of oil compounds was significantly faster in the Fluortex system and most likely related to the greater bioavailability of oil compounds as compared to the clay bead system.


Assuntos
Gammaproteobacteria , Poluição por Petróleo , Petróleo , Petróleo/metabolismo , Argila , Água do Mar/química , Biodegradação Ambiental , Bactérias/metabolismo , Hidrocarbonetos/metabolismo
20.
Nanoscale ; 15(45): 18457-18472, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37941481

RESUMO

Clay nanoparticles, in particular synthetic smectites, have generated interest in the field of tissue engineering and regenerative medicine due to their utility as cross-linkers for polymers in biomaterial design and as protein release modifiers for growth factor delivery. In addition, recent studies have suggested a direct influence on the osteogenic differentiation of responsive stem and progenitor cell populations. Relatively little is known however about the mechanisms underlying nanoclay bioactivity and in particular the cellular processes involved in nanoclay-stem cell interactions. In this study we employed confocal microscopy, inductively coupled plasma mass spectrometry and transmission electron microscopy to track the interactions between clay nanoparticles and human bone marrow stromal cells (hBMSCs). In particular we studied nanoparticle cellular uptake mechanisms and uptake kinetics, intracellular trafficking pathways and the fate of endocytosed nanoclay. We found that nanoclay particles present on the cell surface as µm-sized aggregates, enter hBMSCs through clathrin-mediated endocytosis, and their uptake kinetics follow a linear increase with time during the first week of nanoclay addition. The endocytosed particles were observed within the endosomal/lysosomal compartments and we found evidence for both intracellular degradation of nanoclay and exocytosis as well as an increase in autophagosomal activity. Inhibitor studies indicated that endocytosis was required for nanoclay upregulation of alkaline phosphatase activity but a similar dependency was not observed for autophagy. This study into the nature of nanoclay-stem cell interactions, in particular the intracellular processing of nanosilicate, may provide insights into the mechanisms underlying nanoclay bioactivity and inform the successful utilisation of clay nanoparticles in biomaterial design.


Assuntos
Células-Tronco Mesenquimais , Nanopartículas , Humanos , Osteogênese , Argila , Engenharia Tecidual , Materiais Biocompatíveis , Nanopartículas/química
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