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1.
Pestic Biochem Physiol ; 198: 105754, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38225096

RESUMO

Ralstonia solanacearum (R. solanacearum) is one of the most devastating pathogens in terms of losses in agricultural production. Bentonite (Bent) is a promising synergistic agent used in development of effective and environmentally friendly pesticides against plant disease. However, the synergistic mechanism of Bent nanoclays with benzothiazolinone (BIT) against R. solanacearum is unknown. In this work, acid-functionalized porous Bent and cetyltrimethylammonium bromide (CTAB) were employed as the core nanoclays, and BIT was loaded into the clay to form BIT-loaded CT-Bent (BIT@CT-Bent) for the control of bacterial wilt disease. BIT@CT-Bent exhibited pH-responsive release behavior that fit the Fickian diffusion model, rapidly releasing BIT in an acidic environment (pH = 5.5). The antibacterial effect of BIT@CT-Bent was approximately 4 times greater than that of the commercial product BIT, and its biotoxicity was much lower than that of BIT under the same conditions. Interestingly, R. solanacearum attracted BIT@CT-Bent into the nanocomposites and induced cytoplasmic leakage and changes in membrane permeability, indicating an efficient and synergistic bactericidal effect that rapidly reduced bacterial density. In addition, BIT@CT-Bent significantly inhibited R. solanacearum biofilm formation and swimming activity, by suppressing the expression of phcA, solR and vsrC. Indeed, exogenous application of BIT@CT-Bent significantly suppressed the virulence of R. solanacearum on tobacco plants, with control effect of 75.48%, 72.08% and 66.08% at 9, 11 and 13 days after inoculation, respectively. This study highlights the potential of using BIT@CT-Bent as an effective, eco-friendly bactericide to control bacterial wilt diseases and for the development of sustainable crop protection strategies.


Assuntos
Bentonita , Ralstonia solanacearum , Bentonita/farmacologia , Bentonita/metabolismo , Antibacterianos/farmacologia , Virulência , Concentração de Íons de Hidrogênio , Ralstonia solanacearum/metabolismo , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
2.
Cells ; 13(2)2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38275825

RESUMO

Unlike MCF-7 cells, MDA-MB-231 cells are unresponsive to hormone therapy and often show resistance to chemotherapy and radiotherapy. Here, the antiproliferative effect of biocompatible montmorillonite (Mt) nanosheets on MDA-MB-231 and MCF-7 human breast cancer cells was evaluated by MTT assay, flow cytometry, and qRT-PCR. The results showed that the Mt IC50 for MDA-MB-231 and MCF-7 cells in a fetal bovine serum (FBS)-free medium was ~50 and ~200 µg/mL, and in 10% FBS medium ~400 and ~2000 µg/mL, respectively. Mt caused apoptosis in both cells by regulating related genes including Cas-3, P53, and P62 in MDA-MB-231 cells and Bcl-2, Cas-8, Cas-9, P53, and P62 in MCF-7 cells. Also, Mt arrested MCF-7 cells in the G0/G1 phase by altering Cyclin-D1 and P21 expression, and caused sub-G1 arrest and necrosis in both cells, possibly through damaging the mitochondria. However, fewer gene expression changes and more sub-G1 arrest and necrosis were observed in MDA-MB-231 cells, confirming the higher vulnerability of MDA-MB-231 cells to Mt. Furthermore, MDA-MB-231 cells appeared to be much more vulnerable to Mt compared to other cell types, including normal lung fibroblast (MRC-5), colon cancer (HT-29), and liver cancer (HepG2) cells. The higher vulnerability of MDA-MB-231 cells to Mt was inferred to be due to their higher proliferation rate. Notably, Mt cytotoxicity was highly dependent on both the Mt concentration and serum level, which favors Mt for the local treatment of MDA-MB-231 cells. Based on these results, Mt can be considered as an antiproliferative nanoagent against MDA-MB-231 cells and may be useful in the development of local nanoparticle-based therapies.


Assuntos
Bentonita , Neoplasias da Mama , Humanos , Feminino , Células MCF-7 , Bentonita/farmacologia , Bentonita/metabolismo , Proliferação de Células , Proteína Supressora de Tumor p53/metabolismo , Neoplasias da Mama/tratamento farmacológico , Necrose
3.
Int J Biol Macromol ; 258(Pt 1): 128874, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38128797

RESUMO

This study presents a novel approach in the synthesis and characterization of nanocomposites comprising cationic chitosan (CCS) blended with varying concentrations of silver nanoparticles/montmorillonite (AgNPs/MMT). AgNPs/MMT was synthesized using soluble starch as a reducing and stabilizing agent. Subsequently, nanocomposites, namely CCS/AgMMT-0, CCS/AgMMT-0.5, CCS/AgMMT-1.5, and CCS/AgMMT-2.5, were developed by blending 2.5 g of CCS with 0, 0.5, 1.5, and 2.5 g of AgNPs/MMT, respectively, and the corresponding nanocomposites were prepared using ball milling technique. Transmission electron microscopy (TEM) analysis revealed the formation of nanocomposites that exhibiting nearly spherical morphologies. Dynamic light scattering (DLS) measurements displayed average particle sizes of 1183 nm, 131 nm, 140 nm, and 188 nm for CCS/AgMMT-0, CCS/AgMMT-0.5, CCS/AgMMT-1.5, and CCS/AgMMT-2.5, respectively. The narrow polydispersity index (~0.5) indicated uniform particle size distributions across the nanocomposites, affirming monodispersity. Moreover, the zeta potential values exceeding 30 mV across all nanocomposites that confirmed their stability against agglomeration. Notably, CCS/AgMMT-2.5 nanocomposite exhibited potent antibacterial and antibiofilm properties against diverse pipeline materials. Findings showed that after 15 days of incubation, the highest populations of biofilm cells, Pseudomonas aeruginosa biofilm, developed over UPVC, MDPE, DCI, and SS, with corresponding HPCs of 4.79, 6.38, 8.81, and 7.24 CFU/cm2. The highest cell densities of Enterococcus faecalis biofilm in the identical situation were 4.19, 5.89, 8.12, and 6.9 CFU/cm2. The nanocomposite CCS/AgMMT-2.5 exhibited the largest measured zone of inhibition (ZOI) against both P. aeruginosa and E. faecalis, with measured ZOI values of 19 ± 0.65 and 17 ± 0.21 mm, respectively. Remarkably, the research indicates that the youngest biofilm exhibited the most notable rate of inactivation when exposed to a dose of 150 mg/L, in comparison to the mature biofilm. These such informative findings could offer valuable insights into the development of effective antibiofilm agents and materials applicable in diverse sectors such as water treatment facilities, medical devices, and industrial pipelines.


Assuntos
Quitosana , Nanopartículas Metálicas , Nanocompostos , Prata/farmacologia , Bentonita/farmacologia , Quitosana/farmacologia , Antibacterianos/farmacologia , Cátions/farmacologia , Biofilmes , Testes de Sensibilidade Microbiana
4.
ACS Appl Bio Mater ; 6(11): 4961-4971, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37832028

RESUMO

By intercalating montmorillonite (MMT) with Cu2+ and benzalkonium chloride (BAC), the present work constructed a synergistic promotion system (Cu2+/BAC/MMT). MMT not only enhances the thermal stability of Cu2+ and BAC but also facilitates the controlled release of Cu2+ and BAC. Concurrently, the introduction of BAC improves the material's organic compatibility. In vitro assays show that the "MIC+" of Cu2+/BAC/MMT against Staphylococcus aureus is merely 7.32 mg/L and 55.56 mg/L against Escherichia coli. At concentrations of 10 and 25 mg/L, Cu2+/BAC/MMT inactivates 100% of S. aureus and E. coli within 2 h, respectively. Furthermore, it is confirmed that the prepared Cu2+/BAC/MMT exhibits a long-term antibacterial ability through antibacterial experiments and release tests. Also, the biosafety of this material was also substantiated by in vitro cytotoxicity tests. These comprehensive findings indisputably portend that Cu2+/BAC/MMT holds promise to supplant antibiotics as an efficacious treatment modality for bacterial infections.


Assuntos
Bentonita , Compostos de Benzalcônio , Bentonita/farmacologia , Compostos de Benzalcônio/farmacologia , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia
5.
Pol J Vet Sci ; 26(3): 367-376, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37727052

RESUMO

Montmorillonite (MMT), a natural absorbent agent, has widely been accepted for its antidiarrhea function in human and farm animals; however, its specific physicochemical property limits its biological function in practical use. In the current study, raw MMT was loaded by andrographolide, namely andrographolide loaded montmorillonite (AGP-MMT). The microstructure of AGP-MMT was observed by scanning electron microscope (SEM) and X-ray diffraction (XRD). The effect of AGP-MMT on the growth performance, intestinal barrier and inflammation was investigated in an enterotoxigenic Escherichia coli (ETEC) challenged mice model. The results show that the microstructure of MMT was obviously changed after andrographolide modification: AGP-MMT exhibited a large number of spheroid particles, and floccule aggregates, but lower interplanar spacing compared with MMT. ETEC infection induced body weight losses and intestinal barrier function injury, as indicated by a lower villus height and ratio of villus height/crypt depth, whereas the serum levels of diamine oxidase (DAO), D-xylose and ETEC shedding were higher in the ETEC group compared with the CON group. Mice pretreated with AGP-MMT showed alleviated body weight losses and the intestinal barrier function injury induced by ETEC challenge. The villus height and the ratio of villus height/crypt depth, were higher in mice pretreated with AGP-MMT than those pretreated with equal levels of MMT. Pretreatment with AGP-MMT also alleviated the increased concentration of serum tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß), and the corresponding genes in the jejunum induced by ETEC infection in mice. The protein and mRNA levels of IL-1ß were lower in mice pretreated with AGP-MMT than those with equal levels of MMT. The results indicate that AGP-MMT was more effective in alleviating intestinal barrier injury and inflammation in mice with ETEC challenge than MMT.


Assuntos
Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Humanos , Animais , Camundongos , Bentonita/farmacologia , Bentonita/uso terapêutico , Inflamação/prevenção & controle , Inflamação/veterinária , Modelos Animais de Doenças , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária , Redução de Peso
6.
Colloids Surf B Biointerfaces ; 229: 113450, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37451226

RESUMO

The objective of this study was to assess in vitro antibacterial activity of barrier cream (EVB) formulations containing either calcium montmorillonite (CM) or lecithin-amended montmorillonite (CML). All ingredients were generally recognized as safe (GRAS), and clay minerals were specifically studied due to their known ability to adsorb numerous toxins of human clinical relevance. Characterization of the EVB formulations showed good spreadability, pH, appearance, unity, viscosity, and no evidence of phase separation. Colony forming, disk diffusion susceptibility, and agar dilution assays were used to determine the minimal bactericidal concentration (MBC) of total EVB formulations, as well as respective individual ingredients, against E. coli. Active ingredients within the base EVB formulation were found to be essential oils and zinc oxide. EVB-CML at 0.5-25 mg/mL dose-dependently and significantly (p ≤ 0.01) enhanced the antibacterial activity of the base EVB formulation. MBC values for EVB-CML were 2.5 mg/mL in the colony forming assay and 0.75 mg/mL in the agar dilution test, with a zone of inhibition. Both EVB and EVB-CML displayed stronger antibacterial activity than four antimicrobial creams currently marketed in the United States. Moreover, this effect was rapid, favored by high temperature, and product stability testing suggested a shelf life of at least 10 months. Taken together, these findings demonstrate the ability of CML to enhance the antibacterial effect of the base EVB formulation against E. coli. This novel EVB-CML formulation represents a promising advancement toward improved antibacterial efficacy beyond current industry standards for commercial skin creams and sunscreens.


Assuntos
Bentonita , Lecitinas , Humanos , Lecitinas/farmacologia , Bentonita/farmacologia , Argila , Escherichia coli , Ágar/farmacologia , Antibacterianos/farmacologia
7.
Int J Biol Macromol ; 243: 125330, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37307978

RESUMO

Bone defects caused by bone trauma, infection, surgery, or other systemic diseases remain a severe challenge for the medical field. To address this clinical problem, different hydrogels were exploited to promote bone tissue regrowth and regeneration. Keratins are natural fibrous proteins found in wool, hair, horns, nails, and feather. Due to their unique characteristics of outstanding biocompatibility, great biodegradability, and hydrophilic, keratins have been widely applicated in different fields. In our study, the feather keratin-montmorillonite nanocomposite hydrogels that consist of keratin hydrogels serving as the scaffold support to accommodate endogenous stem cells and montmorillonite is synthesized. The introduction of montmorillonite greatly improves the osteogenic effect of the keratin hydrogels via bone morphogenetic protein 2 (BMP-2)/phosphorylated small mothers against decapentaplegic homolog 1/5/8 (p-SMAD 1/5/8)/runt-related transcription factor 2 (RUNX2) expression. Moreover, the incorporation of montmorillonite into hydrogels can improve the mechanical properties and bioactivity of the hydrogels. The morphology of feather keratin-montmorillonite nanocomposite hydrogels was shown by scanning electron microscopy (SEM) to have an interconnected porous structure. The incorporation of montmorillonite into the keratin hydrogels was confirmed by the energy dispersive spectrum (EDS). We prove that the feather keratin-montmorillonite nanocomposite hydrogels enhance the osteogenic differentiation of BMSCs. Furthermore, micro-CT and histological analysis of rat cranial bone defect demonstrated that feather keratin-montmorillonite nanocomposite hydrogels dramatically stimulated bone regeneration in vivo. Collectively, feather keratin-montmorillonite nanocomposite hydrogels can regulate BMP/SMAD signaling pathway to stimulate osteogenic differentiation of endogenous stem cells and promote bone defect healing, indicating their promising candidate in bone tissue engineering.


Assuntos
Bentonita , Osteogênese , Ratos , Animais , Nanogéis , Bentonita/farmacologia , Queratinas/farmacologia , Queratinas/química , Plumas , Regeneração Óssea , Diferenciação Celular , Células-Tronco , Hidrogéis/farmacologia , Hidrogéis/química
8.
Molecules ; 28(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37175109

RESUMO

Foodborne pathogens can have devastating repercussions and significantly threaten public health. Therefore, it is indeed essential to guarantee the sustainability of our food production. Food preservation and storage using nanocomposites is a promising strategy. Accordingly, the present research's objectives were to identify and isolate a few foodborne pathogens from food products, (ii) synthesize and characterize silver nanoparticles (AgNPs) using wet chemical reduction into the lamellar space layer of montmorillonite (MMT), and (iii) investigate the antibacterial potential of the AgNPs/MMT nanocomposite versus isolated strains of bacteria. Six bacterial species, including Escherichia coli, Salmonella spp., Pseudomonas aeruginosa, Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus were isolated from some food products (meat, fish, cheese, and vegetables). The Ag/MMT nanocomposite was synthesized and characterized using UV-visible spectroscopy, transmission electron microscopy, particle size analyzer, zeta potential, X-ray diffraction (XRD), and scanning electron microscopy with dispersive energy X-ray (EDX). The antibacterial effectiveness of the AgNPs/MMT nanocomposite further investigated distinct bacterial species using a zone of inhibition assay and microtiter-based methods. Nanoparticles with a narrow dimension range of 12 to 30 nm were identified using TEM analysis. The SEM was employed to view the sizeable flakes of the AgNPs/MMT. At 416 nm, the most excellent UV absorption was measured. Four silver metallic diffraction peaks were found in the XRD pattern during the study, and the EDX spectrum revealed a strong signal attributed to Ag nanocrystals. AgNPs/MMT figured out the powerful antibacterial action. The AgNPs/MMT nanocomposite confirmed outstanding minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against six isolates of foodborne pathogens, ranging from 15 to 75 µg/mL, respectively. The AgNPs/MMT's antibacterial potential against gram-negative bacteria was noticeably better than gram-positive bacteria. Therefore, the AgNPs/MMT nanocomposite has the potential to be used as a reliable deactivator in food processing and preservation to protect against foodborne pathogenic bacteria. This suggests that the nanocomposite may be effective at inhibiting the growth and proliferation of harmful bacteria in food, which could help to reduce the risk of foodborne illness.


Assuntos
Anti-Infecciosos Locais , Nanopartículas Metálicas , Nanocompostos , Animais , Prata/farmacologia , Prata/química , Bentonita/farmacologia , Bentonita/química , Anti-Infecciosos Locais/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Bactérias , Nanocompostos/química , Difração de Raios X
9.
J Hazard Mater ; 457: 131727, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37257383

RESUMO

Soil environment is a vital place for the occurrence and spread of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). Extracellular DNA-mediated transformation is an important pathway for ARGs horizontal transfer and widely exists in soil environment. However, little information is available on how common soil components affect ARGs transformation. Here, three minerals (quartz, kaolinite, and montmorillonite) and three organic matters (humic acid, biochar, and soot) were selected as typical soil components. A small amount in suspension (0.2 g/L) of most soil components (except for quartz and montmorillonite) promoted transformant production by 1.1-1.6 folds. For a high amount (8 g/L), biochar significantly promoted transformant production to 1.5 times, kaolinite exerted a 30 % inhibitory effect. From the perspective of plasmid, biochar induced a higher proportion of supercoiled plasmid than kaolinite; more dissolved organic matter and metal ions facilitated plasmid aggregation under the near-neutral pH, thus promoted transformation. As for the influence of materials on recipient, although biochar and kaolinite both increased reactive oxygen species (ROS) level and membrane permeability, biochar up-regulated more ROS related genes, resulting in intracellular ROS production and up-regulating the expression of carbohydrate metabolism and transformation related genes. While kaolinite inhibited transformation mainly by causing nutrient deficiency.


Assuntos
Antibacterianos , Solo , Antibacterianos/farmacologia , Genes Bacterianos , Caulim/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Antagonistas de Receptores de Angiotensina/farmacologia , Bentonita/farmacologia , Quartzo/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Plasmídeos/genética
10.
Trop Anim Health Prod ; 55(2): 124, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36943532

RESUMO

The study evaluated how binders affected the feed intake, weight gain, and feed conversion ratio of Small East African goats fed on a variety of native browse-based diets. Twenty-four growing goats with initial body weight approximately 10.5 kg ± 1.3 (mean ± SE) were randomly allocated to the Acacia brevispica and Berchemia discolor with various levels of polyethylene glycol (PEG) and bentonite clay in a factorial completely randomized design. Six treatments (T1-T6) were used with four goats per treatment. The goats were allocated to individual pens with each treatment having 3 replicates. The selected local browse leaf meal was treated with PEG at a level of 25 g/kg and bentonite clay at 20 g/kg. The experiment lasted for 70 days, consisting of a 14-day adaptation period. Average daily feed intake (ADFI), average daily gain (ADG), and feed conversion ratio (FCR) were computed each week. The composition of the CP, OM, EE, NDF, ADF, TEPH, and CT varied greatly, with significant (P < 0.05) changes seen between the various experimental treatments. Diets treated with binders had higher DM Intake, daily weight gains, and total dry matter intake. Goats on diets treated with bentonite clay (T2) performed much better than the one treated with PEG (T1) although there was no statistically significant difference between the two (P > 0.05). Acacia brevispica-based diets treated with binders performed better than Berchemia discolor-based diets. All nutrients' digestibility coefficients were unaffected by the addition of polyethylene glycol 6000 or bentonite clay. It was concluded that bentonite clay as deactivation material can be adopted due to its low cost compared to PEG and its activity to absorb or bind anti-nutritive factors such as tannins in animal feeds. The addition of PEG and bentonite clay to A. brevispica- and B. discolor-based diet can be used to enhance feed utilization as a result of tannins deactivation.


Assuntos
Ração Animal , Fabaceae , Cabras , Animais , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Bentonita/farmacologia , Argila , Dieta/veterinária , Digestão , Cabras/fisiologia , Polietilenoglicóis , Taninos/química , Aumento de Peso
11.
Part Fibre Toxicol ; 20(1): 8, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36899356

RESUMO

BACKGROUND: Montmorillonite (Mt) and its derivatives are now widely used in industrial and biomedical fields. Therefore, safety assessments of these materials are critical to protect human health after exposure; however, studies on the ocular toxicity of Mt are lacking. In particular, varying physicochemical characteristics of Mt may greatly alter their toxicological potential. To explore the effects of such characteristics on the eyes, five types of Mt were investigated in vitro and in vivo for the first time, and their underlying mechanisms studied. RESULTS: The different types of Mt caused cytotoxicity in human HCEC-B4G12 corneal cells based on analyses of ATP content, lactate dehydrogenase (LDH) leakage, cell morphology, and the distribution of Mt in cells. Among the five Mt types, Na-Mt exhibited the highest cytotoxicity. Notably, Na-Mt and chitosan-modified acidic Na-Mt (C-H-Na-Mt) induced ocular toxicity in vivo, as demonstrated by increases corneal injury area and the number of apoptotic cells. Na-Mt and C-H-Na-Mt also induced reactive oxygen species (ROS) generation in vitro and in vivo, as indicated by 2',7'-dichlorofluorescin diacetate and dihydroethidium staining. In addition, Na-Mt activated the mitogen-activated protein kinase signaling pathway. The pretreatment of HCEC-B4G12 cells with N-acetylcysteine, an ROS scavenger, attenuated the Na-Mt-induced cytotoxicity and suppressed p38 activation, while inhibiting p38 activation with a p38-specific inhibitor decreased Na-Mt-induced cytotoxicity. CONCLUSIONS: The results indicate that Mt induces corneal toxicity in vitro and in vivo. The physicochemical properties of Mt greatly affect its toxicological potential. Furthermore, ROS generation and p38 activation contribute at least in part to Na-Mt-induced toxicity.


Assuntos
Bentonita , Neuropatia Óptica Tóxica , Humanos , Espécies Reativas de Oxigênio/metabolismo , Bentonita/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/farmacologia , Apoptose
12.
Drug Dev Ind Pharm ; 49(1): 103-114, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36852769

RESUMO

OBJECTIVE: The present work provides characterization of rheological properties of a new bentonite-based thixotropic gel emulsion nasal spray (AM-301), its nasal residence time, distribution, safety and tolerability. SIGNIFICANCE: The nasal epithelium is a portal of entry for allergens and primary infection by airborne pathogens. Non-pharmacological interventions, which enhance physical and biological barriers, protect against allergens and pathogens without drug-related side effects. AM-301 has shown promising efficacy and safety in the nasal epithelium against viruses (in vitro) and pollen (clinical). METHODS: Technical part (i) spray characterization was performed with a validated droplet size distribution method; evaluation of the rheological properties of the formulation was performed by a validated amplitude sweep method and a validated oscillation, rotation, oscillation; Clinical part (ii) nasal and oropharyngeal endoscopy were used to provide a semi-quantitative evaluation of distribution and residence time of fluorescein-labelled AM-301 in the nose and oropharynx of healthy volunteers; (iii) tolerability and safety. RESULTS: (i) The non-Newtonian rheological properties of the formulation allow AM-301 to be sprayed and then to revert to a gel to prevent run-off from the nasal cavity; (ii) the formulation remains on the inferior turbinate, septum and oropharynx of volunteers for up to 210 min and on the middle turbinate for up to 60 min; two nasal sprays provide no substantial benefit over a single application with regards to coverage or retention; (iii) the spray is well tolerated. CONCLUSIONS: Single dose spray delivery of AM-301 provides extended coverage of the nasal mucosa up to the inferior turbinates.


Assuntos
Bentonita , Sprays Nasais , Humanos , Administração Intranasal , Bentonita/farmacologia , Emulsões/farmacologia , Mucosa Nasal
13.
Int J Biol Macromol ; 228: 111-122, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36563819

RESUMO

In this study, a methacrylic gelatin/oxidized dextran/montmorillonite­strontium/polypyrrole (GOMP) hydrogel was prepared. The GOMP hydrogel had dual network structure which was formed through photoinitiator-initiated double bond polymerization and Schiff base reaction. The network structure led to a sustained release of the antitumor drug, doxorubicin (DOX). Polypyrrole introduced the conductivity and high photothermal conversion capacity to the GOMP hydrogel, which showed a photothermal conversion efficiency of 31.61 % under 808 nm laser radiation. The GOMP hydrogel had good swelling properties in solvents. Further study showed that the GOMP hydrogel had good biocompatibility and excellent biodegradability in vitro and in vivo. The experiments of in vitro tumor therapy and in vivo anti-tumor recurrence indicated that the DOX-loaded GOMP hydrogel had synergistic effects on tumor cell apoptosis based on chemotherapy and photothermal therapy. In addition, montmorillonite­strontium (MMT-Sr) doped in the hydrogel not only improved the mechanical properties of the hydrogel but also promoted potential bone regeneration. The multifunctional DOX-loaded GOMP hydrogel with bone regeneration, photothermal therapy, and chemotherapy functions has great potential application for treating osteosarcoma.


Assuntos
Neoplasias Ósseas , Hipertermia Induzida , Osteossarcoma , Humanos , Polímeros/química , Gelatina/farmacologia , Hidrogéis/química , Bentonita/farmacologia , Linhagem Celular Tumoral , Fototerapia , Pirróis , Recidiva Local de Neoplasia , Osteossarcoma/tratamento farmacológico , Doxorrubicina/farmacologia , Doxorrubicina/química , Regeneração Óssea , Neoplasias Ósseas/tratamento farmacológico
14.
BMC Vet Res ; 18(1): 387, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329452

RESUMO

BACKGROUND: Montmorillonite clay modified by organosulfur surfactants possesses high cation exchange capacity (CEC) and adsorption capacity than their unmodified form (UM), therefore they may elevate the adverse impact of aflatoxin B1 (AFB1) on ruminal fermentation and methanogenesis. Chemical and mechanical modifications were used to innovate the organically modified nano montmorillonite (MNM). The UM was modified using sodium dodecyl sulfate (SDS) and grounded to obtain the nanoscale particle size form. The dose-response effects of the MNM supplementation to a basal diet contaminated or not with AFB1 (20 ppb) were evaluated in vitro using the gas production (GP) system. The following treatments were tested: control (basal diet without supplementations), UM diet [UM supplemented at 5000 mg /kg dry matter (DM)], and MNM diets at low (500 mg/ kg DM) and high doses (1000 mg/ kg DM). RESULTS: Results of the Fourier Transform Infra-Red Spectroscopy analysis showed shifts of bands of the OH-group occurred from lower frequencies to higher frequencies in MNM, also an extra band at the lower frequency range only appeared in MNM compared to UM. Increasing the dose of the MNM resulted in linear and quadratic decreasing effects (P < 0.05) on GP and pH values. Diets supplemented with the low dose of MNM either with or without AFB1 supplementation resulted in lower (P = 0.015) methane (CH4) production, ruminal pH (P = 0.002), and ammonia concentration (P = 0.002) compared to the control with AFB1. Neither the treatments nor the AFB1 addition affected the organic matter or natural detergent fiber degradability. Contamination of AFB1 reduced (P = 0.032) CH4 production, while increased (P < 0.05) the ruminal pH and ammonia concentrations. Quadratic increases (P = 0.012) in total short-chain fatty acids and propionate by MNM supplementations were observed. CONCLUSION: These results highlighted the positive effects of MNM on reducing the adverse effects of AFB1 contaminated diets with a recommended dose of 500 mg/ kg DM under the conditions of this study.


Assuntos
Aflatoxina B1 , Rúmen , Animais , Aflatoxina B1/toxicidade , Aflatoxina B1/análise , Rúmen/metabolismo , Bentonita/farmacologia , Bentonita/análise , Bentonita/metabolismo , Amônia/análise , Tensoativos/farmacologia , Fermentação , Dieta/veterinária , Ração Animal/análise , Digestão
15.
Toxins (Basel) ; 14(10)2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36287934

RESUMO

In order to alleviate the toxic effects of aflatoxins B1 (AFB1) on inflammatory responses in the intestine, liver, and kidney of broilers, the aflatoxin B1-degrading enzyme, montmorillonite, and compound probiotics were selected and combined to make a triple-action compound mycotoxin detoxifier (CMD). The feeding experiment was divided into two stages. In the early feeding stage (1−21 day), a total of 200 one-day-old Ross broilers were randomly divided into four groups; in the later feeding stage (22−42 day), 160 broilers aged at 22 days were assigned to four groups: Group A: basal diet (4.31 µg/kg AFB1); Group B: basal diet with 40 µg/kg AFB1; Group C: Group A plus 1.5 g/kg CMD; Group D: Group B plus 1.5 g/kg CMD. After the feeding experiment, the intestine, liver, and kidney tissues of the broilers were selected to investigate the molecular mechanism for CMD to alleviate the tissue damages. Analyses of mRNA abundances and western blotting (WB) of inflammatory factors, as well as immunohistochemical (IHC) staining of intestine, liver, and kidney tissues showed that AFB1 aggravated the inflammatory responses through NF-κB and TN-α signaling pathways via TLR pattern receptors, while the addition of CMD significantly inhibited the inflammatory responses. Phylogenetic investigation showed that AFB1 significantly increased interleukin-1 receptor-associated kinase (IRAK-1) and mitogen-activated protein kinase (MAPK) activities (p < 0.05), which were restored to normal levels by CMD addition, indicating that CMD could alleviate cell inflammatory damages induced by AFB1.


Assuntos
Aflatoxina B1 , Micotoxinas , Animais , Aflatoxina B1/análise , Galinhas , Micotoxinas/análise , Bentonita/farmacologia , NF-kappa B , Quinases Associadas a Receptores de Interleucina-1/farmacologia , Filogenia , Fígado , Rim , Intestinos/química , RNA Mensageiro , Proteínas Quinases Ativadas por Mitógeno , Ração Animal/análise
16.
Molecules ; 27(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36144533

RESUMO

A facile, ecofriendly, and cost-effective method was developed to prepare a microporous material based on natural chemically modified bentonite with silver ions (BN-Ag0). This material presents a good catalytic activity against Malachite Green (MG) dye and bacteriostatic activity against a newly isolated bacterium from sewage sludge named hereafter "ISO SS" and Escherichia coli (E. coli). BN-Ag0 was characterized by the following methods: energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), Fourier-transform infrared (FTIR) spectroscopy, temperature programmed desorption (TPD) and X-ray Diffraction (XRD). The new bacterium ISO SS, was isolated using the technique of isolating a pure culture of anaerobically stabilized sludge. A mandatory characterization of ISO SS isolated strains from anaerobic stabilized sludge was performed in the process of identifying bacterial species. The cationic clay-based nanomaterial showed appreciable antibacterial activity against ISO SS, a Gram-negative bacterium. It also showed good activity against E. coli bacteria. As a catalyst in the catalytic ozonation of MG dye, BN-Ag0 significantly improves the oxidation time of the dye, due to its good adsorption and catalytic properties. The catalytic and antibacterial activities of the natural bentonite (BN) and of BN-Ag0 were examined using performant characterization techniques. The lifetime of the BN-Ag0 catalyst was also evaluated. Results obtained are expected to provide valuable findings for the preparation of a good microporous material with multiple functionalities.


Assuntos
Nanopartículas Metálicas , Ozônio , Antibacterianos/química , Antibacterianos/farmacologia , Bentonita/química , Bentonita/farmacologia , Argila , Escherichia coli , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Ozônio/farmacologia , Corantes de Rosanilina , Esgotos , Prata/química , Prata/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
17.
Pak J Biol Sci ; 25(8): 755-764, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36098202

RESUMO

<b>Background and Objective:</b> The inclusion of clay minerals in dairy nutrition is getting attention owing to their proven beneficial effects. The current study aimed to evaluate the effect of dietary supplementation of three different clay minerals (bentonite, zeolite and humic acid) on the performance of lactating Boer goats. <b>Materials and Methods:</b> Twenty lactating Boer goats (having an average body weight ~42.7 kg) were divided into four groups (5 animals each) by using a completely randomized design (CRD). Each group was fed with one of four dietary treatments: Control group with basal ration R1: Consisting of concentrate feed mixture (CFM) and clover hay (50:50%, C:R) on a dry matter (DM) basis, R2: Basal ration plus 1% bentonite, R3: Basal ration plus 1.25% zeolite and R4: Basal ration plus 0.5% humic acid. <b>Results:</b> The results revealed that bentonite and humic acid increased (p<0.05) the nutrient digestibility and nutritive values compared to zeolite and control groups. Ruminal ammonia and total volatile fatty acids (TVFAs) contents increased (p<0.05) with supplementation of bentonite. No effect of clays supplementation was observed on plasma total protein, urea and creatinine, however, it increased (p<0.05) the albumin concentration and albumin/globulin ratios compared to the control while decreasing the plasma globulin contents. Supplementation of humic acid increased (p<0.05) the AST concentrations. Bentonite supplementation recorded the highest milk yield (p<0.05) and composition, while the zeolite group had the lowest values. <b>Conclusion:</b> The present study indicated that the inclusion of clay minerals particularly bentonite (at 1%) can positively affect the performance of lactating Boer goats.


Assuntos
Rúmen , Zeolitas , Albuminas , Animais , Bentonita/metabolismo , Bentonita/farmacologia , Argila , Dieta/veterinária , Feminino , Fermentação , Cabras , Substâncias Húmicas , Lactação , Leite/metabolismo , Nutrientes/metabolismo , Rúmen/metabolismo , Zeolitas/metabolismo , Zeolitas/farmacologia
18.
Harmful Algae ; 117: 102262, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35944948

RESUMO

One of the main symptoms of eutrophication is the proliferation of phytoplankton biomass, including nuisance cyanobacteria. Reduction of the external nutrient load is essential to control eutrophication, and in-lake interventions are suggested for mitigating cyanobacterial blooms to accelerate ecosystem recovery. Floc & Sink (F&S) is one such intervention technique that consists of applying a low dose of coagulants in combination with ballasts for removing cyanobacteria biomass. It is especially suitable for deep lakes with an external nutrient load that is higher than the internal load and suffers from perennial cyanobacterial bloom events. Studies showing the efficacy of the F&S technique have been published, but those testing its variation in efficacy with changes in the environmental conditions are still scarce. Therefore, we evaluated the efficiency of the F&S technique to remove cyanobacteria from water samples collected monthly from two different sites in a deep tropical reservoir (Funil Reservoir, Brazil) in the laboratory. We tested the efficacy of two coagulants, chitosan (CHI) and poly-aluminum chloride (PAC), alone and in combination with lanthanum-modified bentonite (LMB) in settling phytoplankton biomass. We hypothesized that: ⅰ) the combined treatments are more effective in removing the algal biomass and ⅱ) the efficiency of F&S treatments varies spatially and monthly due to changes in environmental conditions. The combined treatments (PAC + LMB or CHI + LMB) removed up to seven times more biomass than single treatments (PAC, CHI, or LMB). Only the treatments CHI and LMB + CHI differed in efficiency between the sites, although all treatments showed significant variation in efficiency over the months at both the sampling sites. The combined treatments exhibited lower removal efficacy during the warm-rainy months (October-March) than during the mild-cold dry months (April-September). At high pH (pH > 10), the efficiency of the CHI and LMB + CHI treatments decreased. CHI had lower removal efficiency when single-cell cyanobacteria were abundant, while the combined treatments were equally efficient regardless of the morphology of the cyanobacteria. Hence, the combination of PAC as a coagulant with a ballast LMB is the most effective technique to precipitate cyanobacteria under the conditions that are encountered around the year in this tropical reservoir.


Assuntos
Cianobactérias , Ecossistema , Bentonita/farmacologia , Eutrofização , Lagos , Fitoplâncton
19.
Vet Med Sci ; 8(6): 2422-2433, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36040758

RESUMO

BACKGROUND: Bentonite, a montmorillonite clay, has been used as a classical remedy strategy for a long time. Recently, bentonite has been used as a raw material in cosmetic products because of its antibacterial and antioxidant properties. However, the therapeutic effect of bentonite on burn injuries has not yet been identified. OBJECTIVES: The aim of this study was to explore the therapeutic effect of a novel bentonite complex, which was developed for medical use, on burn wounds and the anti-inflammatory function of bentonite clay in the complex in vitro. METHODS: A novel bentonite complex and bentonite clay were prepared for each in vivo and in vitro assay (C&L Biotech, Seoul, Korea). Burn wounds were induced on the dorsal skin of two Yucatan minipigs, and effects of tissue regeneration and anti-inflammation were assessed by histological and gene expression analysis. RESULTS: The bentonite complex improved skin regeneration in burn wounds by inducing collagen synthesis, cell proliferation and angiogenesis in vivo. Furthermore, expression of inflammatory cytokines was significantly inhibited by treatment of the bentonite complex. In vitro study for identification of anti-inflammatory effect showed that bentonite clay significantly regulated COX-2 signalling in both HacaT keratinocytes and 3D4/2 macrophage cell lines. CONCLUSIONS: This study identified the therapeutic effect of a novel bentonite complex in burn wounds by inducing skin regeneration and bentonite-mediated anti-inflammatory responses.


Assuntos
Antibacterianos , Bentonita , Animais , Suínos , Bentonita/farmacologia , Bentonita/uso terapêutico , Argila , Porco Miniatura , Antioxidantes
20.
Exp Parasitol ; 240: 108330, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35868573

RESUMO

BACKGROUND: Acanthamoeba keratitis is a painful, sight-threatening infection. It is commonly associated with the use of contact lens. Several lines of evidence suggest inadequate contact lens solutions especially against the cyst forms of pathogenic Acanthamoeba, indicating the need to develop effective disinfectants. OBJECTIVE: In this work, the application and assessment of montmorillonite clay (Mt-clay), cetylpyridinium chloride (CPC) and cetylpyridinium chloride-montmorillonite clay complex (CPC-Mt) against keratitis-causing A. castellanii belonging to the T4 genotype was studied. METHODS: Adhesion to human cells and amoeba-mediated cytopathogenicity assays were conducted to determine the impact of Mt-clay, CPC and CPC-Mt complex on amoeba-mediated binding and host cell death. Furthermore, assays were also performed to determine inhibitory effects of Mt-clay, CPC and CPC-Mt complex on encystment and excystment. In addition, the cytotoxicity of Mt-clay, CPC and CPC-Mt complex against human cells was examined. RESULTS: The results revealed that CPC and CPC-Mt complex presented significant antiamoebic effects against A. castellanii at microgram dose. Also, the CPC and CPC-Mt complex inhibited amoebae binding to host cells. Furthermore, CPC and CPC-Mt complex, were found to inhibit the encystment and excystment processes. Finally, CPC and CPC-Mt complex showed minimal host cell cytotoxicity. These results show that CPC and CPC-Mt complex exhibit potent anti-acanthamoebic properties. CONCLUSION: Given the ease of usage, safety, cost-effectiveness and long-term stability, CPC and CPC-Mt complex can prove to be an excellent choice in the rational development of contact-lens disinfectants to eradicate pathogenic Acanthamoeba effectively.


Assuntos
Ceratite por Acanthamoeba , Acanthamoeba castellanii , Lentes de Contato , Ceratite por Acanthamoeba/etiologia , Ceratite por Acanthamoeba/prevenção & controle , Bentonita/farmacologia , Cetilpiridínio/farmacologia , Argila , Soluções para Lentes de Contato/farmacologia , Lentes de Contato/efeitos adversos , Desinfecção/métodos , Humanos
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