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1.
J Environ Manage ; 360: 121086, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38733841

RESUMO

This research focuses on the synthesis and application of a novel kaolin-supported g-C3N4/MoO3 nanocomposite for the degradation of tetracycline, an important antibiotic contaminant in water systems. The nanocomposite was prepared through a facile and environmentally friendly approach, leveraging the adsorption and photocatalytic properties of kaolin, g-C3N4 and MoO3 nanoparticles, respectively. Comprehensive characterization of the nanocomposite was conducted using techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and optical spectra. The surface parameters were studied using N2 adsorption-desorption isotherm. The elemental composition was studied using X-ray photoelectron spectroscopy. The efficiency of the developed nanocomposite in tetracycline degradation was evaluated and the results revealed an efficient tetracycline degradation exhibiting the synergistic effects of adsorption and photocatalytic degradation in the removal process. The tetracycline degradation was achieved in 60 min. Kinetic studies and thermodynamic analyses provided insights into the degradation mechanism, suggesting potential applications for the nanocomposite in wastewater treatment. Additionally, the recyclability and stability of the nanocomposite were investigated, demonstrating its potential for sustainable and long-term application in water treatment.


Assuntos
Caulim , Nanocompostos , Tetraciclina , Poluentes Químicos da Água , Purificação da Água , Tetraciclina/química , Nanocompostos/química , Adsorção , Purificação da Água/métodos , Caulim/química , Poluentes Químicos da Água/química , Catálise , Águas Residuárias/química , Difração de Raios X , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Food Chem ; 453: 139701, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38781907

RESUMO

The current study offers the nanomolar quantification of gallic acid (GAL) based on gold nanoparticles (AuNps) and kaolinite minerals (KNT) modified on a screen-printed electrode (SPE). The electrochemical behavior of GAL was performed using differential pulse voltammetry (DPV) in Britton Robinson (BR) buffer solution at pH 2.0 as a supporting electrolyte. Under the optimized DPV mode parameters, the oxidation peak current of GAL (at 0.72 V vs Ag/AgCl) increased linearly in the range between 0.002 µmolL-1 and 40.0 µmolL-1 with a detection limit of 0.50 nmolL-1. The effect of common interfering agents was also investigated. Finally, the applicability of the proposed method was verified by quantification analysis of GAL in black tea and pomegranate juice samples.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Ácido Gálico , Ouro , Caulim , Nanopartículas Metálicas , Nanopartículas Metálicas/química , Ouro/química , Ácido Gálico/análise , Ácido Gálico/química , Caulim/química , Técnicas Eletroquímicas/instrumentação , Limite de Detecção , Punica granatum/química , Chá/química , Minerais/análise , Minerais/química , Sucos de Frutas e Vegetais/análise , Camellia sinensis/química , Contaminação de Alimentos/análise
3.
Molecules ; 29(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38792071

RESUMO

Every year, new compounds contained in consumer products, such as detergents, paints, products for personal hygiene, and drugs for human and veterinary use, are identified in wastewater and are added to the list of molecules that need monitoring. These compounds are indicated with the term emerging contaminants (or Contaminants of Emerging Concern, CECs) since they are potentially dangerous for the environment and human health. To date, among the most widely used methodologies for the removal of CECs from the aquatic environment, adsorption processes play a role of primary importance, as they have proven to be characterized by high removal efficiency, low operating and management costs, and an absence of undesirable by-products. In this paper, the adsorption of ibuprofen (IBU), a nonsteroidal anti-inflammatory drug widely used for treating inflammation or pain, was performed for the first time using two different types of geopolymer-based materials, i.e., a metakaolin-based (GMK) and an organic-inorganic hybrid (GMK-S) geopolymer. The proposed adsorbing matrices are characterized by a low environmental footprint and have been easily obtained as powders or as highly porous filters by direct foaming operated directly into the adsorption column. Preliminary results demonstrated that these materials can be effectively used for the removal of ibuprofen from contaminated water (showing a concentration decrease of IBU up to about 29% in batch, while an IBU removal percentage of about 90% has been reached in continuous), thus suggesting their potential practical application.


Assuntos
Ibuprofeno , Poluentes Químicos da Água , Purificação da Água , Ibuprofeno/química , Ibuprofeno/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/química , Adsorção , Purificação da Água/métodos , Polímeros/química , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Águas Residuárias/química , Caulim/química
4.
Environ Res ; 252(Pt 4): 119085, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38719067

RESUMO

Electrokinetic-Permeable Reaction Barrier (EK-PRB) coupled remediation technology can effectively treat heavy metal-contaminated soil near coal mines. This study was conducted on cadmium (Cd), a widely present element in the soil of the mining area. To investigate the impact of the voltage gradient on the remediation effect of EK-PRB, the changes in current, power consumption, pH, and Cd concentration content during the macroscopic experiment were analyzed. A three-dimensional visualized kaolinite-heavy metal-water simulation system was constructed and combined with the Molecular Dynamics (MD) simulations to elucidate the migration mechanism and binding active sites of Cd on the kaolinite (001) crystalline surface at the microscopic scale. The results showed that the voltage gradient positively correlates with the current, power consumption, and Cd concentration during EK-PRB remediation, and the average removal efficiency increases non-linearly with increasing voltage gradient. Considering power consumption, average removal efficiency, and cost-effectiveness, the voltage range is between 1.5 and 3.0 V/cm, with 2.5 V/cm being the optimal value. The results of MD simulations and experiments correspond to each other. Cd2+ formed a highly stable adsorption structure in contrast to the Al-O sheet on the kaolinite (001) crystalline surface. The mean square displacement (MSD) curve of Cd2+ under the electric field exhibits anisotropy, the total diffusion coefficient DTotal increases and the Cd2+ migration rate accelerates. The electric field influences the microstructure of Cd2+ complexes. With the enhancement of the voltage gradient, the complexation between Cd2+ and water molecules is enhanced, and the interaction between Cd2+ and Cl- in solution is weakened.


Assuntos
Cádmio , Recuperação e Remediação Ambiental , Simulação de Dinâmica Molecular , Cádmio/química , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/química , Caulim/química
5.
J Hazard Mater ; 472: 134494, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38703688

RESUMO

Enteric virus concentration in large-volume water samples is crucial for detection and essential for assessing water safety. Certain dissolution and suspension components can affect the enrichment process. In this study, tangential flow ultrafiltration (TFUF) was used as an enrichment method for recovering enteric virus in water samples. Interestingly, the bacteriophage MS2 recovery in reclaimed water and the reclaimed water without particles were higher than that in ultrapure water. The simulated reclaimed water experiments showed that humic acid (HA) (92.16% ± 4.32%) and tryptophan (Try) (81.50 ± 7.71%) enhanced MS2 recovery, while the presence of kaolin (Kaolin) inhibited MS2 recovery with an efficiency of 63.13% ± 11.17%. Furthermore, Atomic force microscopy (AFM) revealed that the MS2-HA cluster and the MS2-Try cluster had larger roughness values on the membrane surface, making it difficult to be eluted, whereas MS2-Kaolin cluster had compact surfaces making it difficult to be eluted. Additionally, the MS2-HA cluster is bound to the membrane by single hydrogen bond with SO, whereas both the MS2-Try cluster and the MS2-Kaolin cluster are bound to the membrane by two hydrogen bonds, making eluting MS2 challenging. These findings have potential implications for validating standardized methods for virus enrichment in water samples.


Assuntos
Substâncias Húmicas , Caulim , Levivirus , Ultrafiltração , Ultrafiltração/métodos , Levivirus/isolamento & purificação , Substâncias Húmicas/análise , Caulim/química , Triptofano/química , Microbiologia da Água , Purificação da Água/métodos
6.
Bioresour Technol ; 400: 130676, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38588783

RESUMO

This work focuses to the value added utilization of animal sewage sludge into gases, bio-oil and char using synthetic zeolite (ZSM-5 and Y-zeolite) and natural sourced (diatomite, kaolin, perlite) materials as catalysts. Pyrolysis was performed in a one-stage bench-scale reactor at temperatures of 400 and 600 °C. The catalyst was mixed with the raw material before the pyrolysis. Catalysts had a significant effect on the yield of products, because the amount of volatile products was higher in their presence, than without them. In case of kaolin, due to the structural transformation occurring between 500-600 °C, a significant increase in activity was observed in terms of pyrolysis reactions resulting in volatiles. The hydrogen content of the gas products increased significantly at a temperature of 600 °C and in thermo-catalysts pyrolysis. In the presence of catalysts, bio-oil had more favourable properties.


Assuntos
Óleos de Plantas , Polifenóis , Pirólise , Esgotos , Zeolitas , Zeolitas/química , Catálise , Esgotos/química , Biocombustíveis , Óxido de Alumínio/química , Caulim/química , Temperatura Alta , Dióxido de Silício/química , Temperatura , Carvão Vegetal/química
7.
PLoS One ; 19(4): e0300102, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38557823

RESUMO

Backfill mining is an effective way to solve environment pollute, surface subsidence, and groundwater system damage which caused by coal mining. However, the complex underground environment may change the physical and mechanical properties of the backfill body, which poses a risk of strength failure. This paper analyzed the failure of gangue-based cemented backfill body which made up of gangue and fly ash. The results show that physicochemical reactions will generate quartz, kaolinite, and other high-strength substances; hydration reaction between the fine particles will generate hydrocalcium silicate and other C-S-H gels, they wrapped gangues as a whole, which provide a high strength of the cemented backfill body. Several experiments were carried out in order to find the reason for failure in samples under loads. The conclusion drawn as following: (1) When the load is large, the cracks extend from the surface of the samples to the interior, at the same time, the length and width of the cracks increasing obviously and connecting as net. Especially the external load exceeds the peak intensity. (2) The relationship between sample failure and pores is weak, but obvious with crack development, especially the cracks connected as a net. (3) The interface structure formed by gangue is an important source of crack development and, thus, will stimulate the development of cracks.


Assuntos
Minas de Carvão , Minas de Carvão/métodos , Caulim
8.
Waste Manag ; 181: 176-187, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38614039

RESUMO

This study presented the influence of two types of clay: kaolin (Kao) and red clay (RC) on the chemical and physical properties of ceramic specimens when galvanic sludge (GS) is incorporated to encapsulate heavy metals. Samples were obtained of GS from the industrial district of Manaus - Amazonas State, Brazil, and kaolin (Kao), and red clay (RC) from the Central Amazon. A fourth sample was prepared by mixing GS, Kao, and RC in the ratio 1:1:8 (GS + Kao + RC). This mixture was ground, and ceramic specimens were prepared, and heat treated at 950 °C and 1200 °C for three hours for phase detection, compressive strength, leaching of Fe, Ni and Cr metals and life cycle assessment. Galvanic sludge, Kao, and RC were also, and heat treated to at 950 °C and 1200 °C for three hours, obtaining GS950, GS1200, Kao950, Kao1200, RC950, and RC1200. The samples were submitted to XRF, XRD, Rietveld refinement, Mössbauer spectroscopy, TG/DTG/DSC, and SEM. The results show that the formation of nickel oxide and a spinel solid solution of the type Fe3+{Fe1-y3+,Fe1-x2+,Nix2+,Cry3+}O4 (in which [] = tetrahedral site, {} octahedral site) occurs in GS1200, which is caused by sulfate decomposition to SO2. At 1200 °C, heavy metals are encapsulated, forming other phases such as nickel silicate and hematite. Life cycle assessment was used to verify the sustainability and value of GS in clay for making bricks, and it indicated that the production of ceramics is feasible, reduces the use of clays, and is sustainable.


Assuntos
Cerâmica , Argila , Caulim , Metais Pesados , Esgotos , Caulim/química , Argila/química , Metais Pesados/química , Metais Pesados/análise , Cerâmica/química , Esgotos/química , Brasil
9.
J Biomater Sci Polym Ed ; 35(7): 1064-1085, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38431865

RESUMO

Severe trauma with massive active blood loss, including liver and spleen rupture, arterial bleeding and pelvic fracture, will lead disability, malformation and even death. Therefore, it is very important to develop new, fast and efficient hemostatic materials. In this study, a novel Gelatin/Kaolin (GE/KA) composite sponge was developed. Meanwhile, to further investigate the effect of kaolin content on sponge properties, we prepared four types of sponges: GE/5% KA, GE/10% KA, GE/15% KA and GE/20% KA. The results of coagulation test in vitro showed that compared to the other groups, there were more activated adhered platelets and red blood cells on the surface of GE/15% KA. The results of hemostasis test in vivo showed that compared to other experimental groups, the GE/15% KA group had significantly less hemostasis time (liver hemostasis model: 69.50 ± 2.81 s; femoral artery hemostasis model: 75.17 ± 3.06 s) and bleeding volume (liver hemostasis model: 219.02 ± 10.39 mg; femoral artery hemostasis model: 948.00 ± 50.69 mg), and was similar to the commercial hemostasis material group. Additionally, the material properties of the sponge were characterized and its biocompatibility was verified as well through cell experiments and in vivo embedding experiments. All these results indicate that the optimal content of kaolin is 15%, which provides a theoretical basis for subsequent research. All in all, the novel GE/KA composite sponge prepared in this study can be used as a multifunctional hemostatic wound dressing for the treatment of complex wounds under various trauma scenes.


Assuntos
Gelatina , Hemostasia , Hemostáticos , Caulim , Cicatrização , Caulim/química , Caulim/farmacologia , Animais , Cicatrização/efeitos dos fármacos , Hemostasia/efeitos dos fármacos , Gelatina/química , Hemostáticos/farmacologia , Hemostáticos/química , Hemostáticos/administração & dosagem , Hemorragia/tratamento farmacológico , Camundongos , Coagulação Sanguínea/efeitos dos fármacos , Masculino , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Humanos , Teste de Materiais
10.
Environ Res ; 251(Pt 1): 118590, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38437900

RESUMO

Estuaries are fragile environment that are most affected by climate change. One of the major consequences of climate change on estuarine processes is the enhancement in salt intrusion leading to higher salinity values. This has several implications on the estuarine sediment dynamics. Of the various factors that affect the flocculation of cohesive sediments, salinity and turbulence have been recognized as to have great significance. Many of the estuaries are contaminated with heavy metals, of which, the concentration of Iron (Fe (II)) are generally on the higher range. However, the influence of Fe (II) on the flocculation of cohesive sediments at various estuarine mixing conditions is not well known. The present study investigated the influence of Fe (II) on the flocculation of kaolin at various concentration of Fe (II), salinity and turbulence shear. The results indicated that Fe (II) and salinity have a positive influence on kaolin flocculation. The increase in turbulence shear caused an initial increase and then a decrease in floc size. In case of sand-clay mixtures, that are observed in mixed sediment estuarine environments, a reduction in the floc size was observed, which is attributed to the breakage of flocs induced by the shear of sand. Breakage coefficient, which is a measure of break-up of flocs, is generally adopted as 0.5 assuming binary breakage. The present study revealed that the breakage coefficient can take values from 0 to 1 and is a direct function of Fe (II) and salinity and an inverse function of turbulence and sand concentration. Thus, a new model for breakage coefficient with the influencing parameters has been proposed, which is an improvement of existing model that is expressed in terms of turbulence alone. Sensitivity analysis showed that the proposed model can very well predict the breakage coefficient of Fe (II) - kaolin flocs. Thus, the model can quantify the breakage coefficient of flocs in estuaries contaminated with Fe (II) that is a vital parameter for population balance models.


Assuntos
Argila , Estuários , Floculação , Sedimentos Geológicos , Caulim , Caulim/química , Argila/química , Sedimentos Geológicos/química , Sedimentos Geológicos/análise , Areia/química , Silicatos de Alumínio/química , Salinidade , Ferro/química , Compostos Ferrosos/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
11.
J Cell Mol Med ; 28(6): e18161, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38445787

RESUMO

Cisplatin is an antimitotic drug able to cause acute and chronic gastrointestinal side effects. Acute side effects are attributable to mucositis while chronic ones are due to neuropathy. Cisplatin has also antibiotic properties inducing dysbiosis which enhances the inflammatory response, worsening local damage. Thus, a treatment aimed at protecting the microbiota could prevent or reduce the toxicity of chemotherapy. Furthermore, since a healthy microbiota enhances the effects of some chemotherapeutic drugs, prebiotics could also improve this drug effectiveness. We investigated whether chronic cisplatin administration determined morphological and functional alterations in mouse proximal colon and whether a diet enriched in prebiotics had protective effects. The results showed that cisplatin caused lack of weight gain, increase in kaolin intake, decrease in stool production and mucus secretion. Prebiotics prevented increases in kaolin intake, changes in stool production and mucus secretion, but had no effect on the lack of weight gain. Moreover, cisplatin determined a reduction in amplitude of spontaneous muscular contractions and of Connexin (Cx)43 expression in the interstitial cells of Cajal, changes that were partially prevented by prebiotics. In conclusion, the present study shows that daily administration of prebiotics, likely protecting the microbiota, prevents most of the colonic cisplatin-induced alterations.


Assuntos
Cisplatino , Prebióticos , Animais , Camundongos , Cisplatino/efeitos adversos , Caulim , Aumento de Peso , Colo
12.
J Environ Manage ; 355: 120506, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38447514

RESUMO

Plenty of heavy metals (HMs) that are adsorbed on clay minerals (such as kaolinite), in addition to low molecular-weight organic acids (such as oxalic acid (OA)) with high activities, are widespread in the natural environment. In the present study, the effects of OA on the environmental behaviors of Pb2+/Cd2+ adsorbed by kaolinite have been investigated. The effectiveness and mechanisms of calcium silicate (CS) and magnesium silicate (MS) in reducing the environmental risks of the HMs have also been studied. The results showed that the releases of Pb2+/Cd2+ increased with an increasing concentration of OA. When different dosages of CS/MS were added to the aging system, a redistribution of HMs took place and the free form of Pb2+/Cd2+ decreased to very low levels. Also, the unextractable Pb2+/Cd2+ increased to high levels. Furthermore, a series of characterizations showed that the released HMs were re-captured by the CS/MS. In addition, the CS immobilized the OA in the solution during the aging process, which also facilitated an immobilization of the carbon element in the environment. In general, the present study has contributed to a further understanding of the transport behaviors of the HMs in natural environments, and of the interactions between CS (or MS), the environmental media, and the heavy metal contaminants. In addition, this study has also provided an eco-friendly strategy for an effective remediation of heavy metal pollution.


Assuntos
Metais Pesados , Poluentes do Solo , Caulim , Cádmio , Chumbo , Metais Pesados/análise , Poluição Ambiental , Poluentes do Solo/análise , Solo
13.
Artigo em Inglês | MEDLINE | ID: mdl-38407539

RESUMO

OBJECTIVE: To describe the use of a synthetic hemostatic dressing, QuikClot Combat Gauze (QCG), in dogs with bleeding wounds. CASE SERIES SUMMARY: Two dogs presented with bleeding traumatic wounds, and QCG was used to achieve hemostasis during stabilization of these dogs. In the other 2 dogs, QCG was used to help attenuate bleeding associated with a surgical procedure. NEW OR UNIQUE INFORMATION PROVIDED: While hemostatic dressings have been widely studied and used in human medicine, there is minimal information on the use and efficacy of these hemostatic dressings in veterinary medicine. This case series describes the use of QCG in dogs with hemorrhaging wounds. QCG could be a valuable resource in veterinary emergency and critical care settings.


Assuntos
Doenças do Cão , Hemostáticos , Cães , Humanos , Animais , Hemostáticos/uso terapêutico , Caulim/uso terapêutico , Hemorragia/terapia , Hemorragia/veterinária , Bandagens/veterinária , Hemostasia , Modelos Animais de Doenças , Doenças do Cão/terapia
14.
Int J Biol Macromol ; 263(Pt 1): 130304, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382796

RESUMO

This present work targets the production of an eco-friendly adsorbent (hereinafter KA/CEL) from kaolin clay functionalized with cellulose extract obtained from peanut shells. The adsorbents were used for decolorization of two different types of organic dyes (cationic: methylene blue, MB; anionic: Congo red, CR) from an aqueous environment. Several analytical methods, including Brunauer-Emmett-Teller (surface properties), Fourier Transforms infrared (functionality), scanning electron microscope, Energy dispersive X-Ray (morphology), and pHpzc test (surface charge), were used to attain the physicochemical characteristics of KA/CEL. The Box-Behnken Design (BBD) was applied to determine the crucial factors affecting adsorption performance. These included cellulose loading at 25 %, an adsorbent dose of 0.06 g, solution pH set at 10 for MB and 7 for CR, a temperature of 45 °C, and contact times of 12.5 min for MB and 20 min for CR dye. The adsorption data exhibited better agreement with the pseudo-second-order kinetic and Freundlich models. The Langmuir model estimated the monolayer capacity to be 291.5 mg/g for MB and 130.7 mg/g for CR at a temperature of 45 °C. This study's pivotal finding underscores the promising potential of KA/CEL as an effective adsorbent for treating wastewater contaminated with organic dyes.


Assuntos
Vermelho Congo , Poluentes Químicos da Água , Corantes/química , Argila , Caulim , Arachis , Azul de Metileno , Celulose , Adsorção , Cinética , Concentração de Íons de Hidrogênio
15.
Behav Processes ; 216: 105001, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336238

RESUMO

"Pica" refers to the ingestion of non-nutritive substances by animals that would not typically consume them. The pica behavior can be utilized to investigate the internal conditions of animals' bodies. For example, rats, due to neuroanatomical reasons, cannot vomit; nevertheless, when nauseated, they ingest kaolin clay. This renders the ingestion of kaolin a practical proxy for measuring nausea in rats. The question of whether rats consume minerals other than kaolin during nauseous episodes remains unanswered. This study aims to identify a mineral better suited for detecting nausea in rats. In two experiments, nausea was induced in laboratory rats by a single dose of lithium chloride (0.15 M, 2% bw), and their mineral consumption over the 24-hour period was measured. Experiment 1 compared three minerals between rat groups: kaolin sold for nausea detection (kaolin A), kaolin for ceramics (kaolin B), and zeolite. Nauseated rats consumed all minerals, with the highest consumption occurring with kaolin B. In Experiment 2, three commercially available health soils were compared: edible kaolin, edible bentonite, and edible chalk. The most significant consumption was observed in the kaolin group, followed by the bentonite group, while nauseated rats did not consume edible chalk. These findings underscore the suitability of kaolin for nausea detection, although the extent of consumption may vary depending on the product.


Assuntos
Caulim , Zeolitas , Ratos , Animais , Bentonita , Carbonato de Cálcio , Pica , Ratos Wistar , Náusea
16.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396728

RESUMO

Chronic Obstructive Pulmonary Disease (COPD) exacerbation is known for its substantial impact on morbidity and mortality among affected patients, creating a significant healthcare burden worldwide. Coagulation abnormalities have emerged as potential contributors to exacerbation pathogenesis, raising concerns about increased thrombotic events during exacerbation. The aim of this study was to explore the differences in thrombelastography (TEG) parameters and coagulation markers in COPD patients during admission with exacerbation and at a follow-up after discharge. This was a multi-center cohort study. COPD patients were enrolled within 72 h of hospitalization. The baseline assessments were Kaolin-TEG and blood samples. Statistical analysis involved using descriptive statistics; the main analysis was a paired t-test comparing coagulation parameters between exacerbation and follow-up. One hundred patients participated, 66% of whom were female, with a median age of 78.5 years and comorbidities including atrial fibrillation (18%) and essential arterial hypertension (45%), and sixty-five individuals completed a follow-up after discharge. No significant variations were observed in Kaolin-TEG or conventional coagulation markers between exacerbation and follow-up. The Activated Partial Thromboplastin Clotting Time (APTT) results were near-significant, with p = 0.08. In conclusion, TEG parameters displayed no significant alterations between exacerbation and follow-up.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Tromboelastografia , Humanos , Feminino , Idoso , Masculino , Tromboelastografia/métodos , Estudos de Coortes , Estudos Prospectivos , Caulim
17.
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
18.
Environ Res ; 247: 118257, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38262511

RESUMO

This study introduces the UV/glucose-oxidase@Kaolin (GOD@Kaolin) coupled organic green rust (OGR) system (UV/OGR/GOD@Kaolin) to investigate the promotion of glucose oxidase activity by UV light and its synergistic degradation mechanism for photosensitive pollutants, specifically targeting the efficient degradation of 4-chlorophenol (4-CP). The enzyme system demonstrates its ability to overcome drawbacks associated with traditional Fenton systems, including a narrow pH range and high localized concentration of H2O2, by gradually releasing hydrogen peroxide in situ within a neutral environment. In the presence of UV radiation under specific conditions, enhanced enzyme activity is observed, resulting in increased efficiency in pollutant removal. The gradual release of hydrogen peroxide plays a crucial role in preventing unwanted reactions among active substances. These unique features facilitate the generation of highly reactive species, such as Fe(IV)O, •OH, and •O2-, tailored to efficiently target the organic components of interest. Additionally, the system establishes a positive iron cycle, ensuring a sustained reactive capability throughout the degradation process. The results highlight the UV/OGR/GOD@Kaolin system as an effective and environmentally friendly approach for the degradation of 4-CP, and the resilience of the enzyme extends the system's applicability to a broader range of scenarios.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Raios Ultravioleta , Peróxido de Hidrogênio/química , Glucose Oxidase/metabolismo , Caulim , Glucose , Oxirredução , Poluentes Químicos da Água/química
19.
Childs Nerv Syst ; 40(5): 1533-1539, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38194082

RESUMO

PURPOSE: Hydrocephalus is a brain disease prevalent in the pediatric population that presents complex pathophysiology and multiple etiologies. The best treatment is still ventricular shunting. Mechanical obstruction is the most frequent complication, but the resulting pathological effects are still unknown. OBJECTIVE: Evaluation and comparison of clinical, histopathological, and immunohistochemical aspects in the acute phase of experimental hydrocephalus induced by kaolin, after treatment with adapted shunt, and after shunt obstruction and posterior disobstruction. METHODS: Wistar rats aged 7 days were used and divided into 4 groups: control group without kaolin injection (n = 6), untreated hydrocephalic group (n = 5), hydrocephalic group treated with ventriculosubcutaneous shunt (DVSC) (n = 7), and hydrocephalic group treated with shunt, posteriorly obstructed and disobstructed (n = 5). The animals were submitted to memory and spatial learning evaluation through the Morris water maze test. The rats were sacrificed at 28 days of age and histological analysis of the brains was performed with luxol fast blue, in addition to immunohistochemical analysis in order to evaluate reactive astrocytosis, inflammation, neuronal labeling, and apoptotic activity. RESULTS: The group with shunt obstruction had worse performance in memory tests. Reactive astrocytosis was more evident in this group, as was the inflammatory response. CONCLUSIONS: Obstruction of the shunt results in impaired performance of behavioral tests and causes irreversible histopathological changes when compared to findings in the group with treated hydrocephalus, even after unblocking the system. The developed model is feasible and efficient in simulating the clinical context of shunt dysfunction.


Assuntos
Hidrocefalia , Caulim , Criança , Humanos , Ratos , Animais , Ratos Wistar , Gliose/patologia , Hidrocefalia/cirurgia , Encéfalo/patologia
20.
J Comp Neurol ; 532(2): e25578, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38175813

RESUMO

Vanadium is a prevalent neurotoxic transition metal with therapeutic potentials in some neurological conditions. Hydrocephalus poses a major clinical burden in neurological practice in Africa. Its primary treatment (shunting) has complications, including infection and blockage; alternative drug-based therapies are therefore necessary. This study investigates the function and cytoarchitecture of motor and cerebellar cortices in juvenile hydrocephalic mice following treatment with varying doses of vanadium. Fifty juvenile mice were allocated into five groups (n = 10 each): controls, hydrocephalus-only, low- (0.15 mg/kg), moderate- (0.3 mg/kg), and high- (3.0 mg/kg) dose vanadium groups. Hydrocephalus was induced by the intracisternal injection of kaolin and sodium metavanadate administered by intraperitoneal injection 72hourly for 28 days. Neurobehavioral tests: open field, hanging wire, and pole tests, were carried out to assess locomotion, muscular strength, and motor coordination, respectively. The cerebral motor and the cerebellar cortices were processed for cresyl violet staining and immunohistochemistry for neurons (NeuN) and astrocytes (glial fibrillary acidic protein). Hydrocephalic mice exhibited body weight loss and behavioral deficits. Horizontal and vertical movements and latency to fall from hanging wire were significantly reduced, while latency to turn and descend the pole were prolonged in hydrocephalic mice, suggesting impaired motor ability; this was improved in vanadium-treated mice. Increased neuronal count, pyknotic cells, neurodegeneration and reactive astrogliosis were observed in the hydrocephalic mice. These were mostly mitigated in the vanadium-treated mice, except in the high-dose group where astrogliosis persisted. These results demonstrate a neuroprotective potential of vanadium administration in hydrocephalus. The molecular basis of these effects needs further exploration.


Assuntos
Hidrocefalia , Vanádio , Animais , Camundongos , Vanádio/efeitos adversos , Gliose/tratamento farmacológico , Caulim/efeitos adversos , Hidrocefalia/induzido quimicamente , Hidrocefalia/tratamento farmacológico , Neurônios
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