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1.
Front Endocrinol (Lausanne) ; 15: 1332237, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38872972

RESUMO

Type 2 diabetes mellitus has a worldwide prevalence of 10.5% in the adult population (20-79 years), and by 2045, the prevalence is expected to keep rising to one in eight adults living with diabetes. Mild cognitive impairment has a global prevalence of 19.7% in adults aged 50 years. Both conditions have shown a concerning increase in prevalence rates over the past 10 years, highlighting a growing public health challenge. Future forecasts indicate that the prevalence of dementia (no estimations done for individuals with mild cognitive impairment) is expected to nearly triple by 2050. Type 2 diabetes mellitus is a risk factor for the development of cognitive impairment, and such impairment increase the likelihood of poor glycemic/metabolic control. High phytate intake has been shown to be a protective factor against the development of cognitive impairment in observational studies. Diary phytate intake might reduce the micro- and macrovascular complications of patients with type 2 diabetes mellitus through different mechanisms. We describe the protocol of the first trial (the PHYND trial) that evaluate the effect of daily phytate supplementation over 56 weeks with a two-arm double-blind placebo-controlled study on the progression of mild cognitive impairment, cerebral iron deposition, and retinal involvement in patients with type 2 diabetes mellitus. Our hypothesis proposes that phytate, by inhibiting advanced glycation end product formation and chelating transition metals, will improve cognitive function and attenuate the progression from Mild Cognitive Impairment to dementia in individuals with type 2 diabetes mellitus and mild cognitive impairment. Additionally, we predict that phytate will reduce iron accumulation in the central nervous system, mitigate neurodegenerative changes in both the central nervous system and retina, and induce alterations in biochemical markers associated with neurodegeneration.


Assuntos
Encéfalo , Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Suplementos Nutricionais , Progressão da Doença , Ferro , Ácido Fítico , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/complicações , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/prevenção & controle , Método Duplo-Cego , Ácido Fítico/administração & dosagem , Retinopatia Diabética/metabolismo , Retinopatia Diabética/tratamento farmacológico , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Ferro/metabolismo , Ferro/administração & dosagem , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Adulto , Administração Oral
2.
J Mater Sci Mater Med ; 35(1): 36, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900219

RESUMO

Calcium phosphate cements, primarily brushite cements, require the addition of setting retarders to ensure adequate processing time and processability. So far, citric acid has been the primary setting retarder used in this context. Due to the poor biocompatibility, it is crucial to explore alternative options for better processing. In recent years, the setting retarder phytic acid (IP6) has been increasingly investigated. This study investigates the biological behaviour of calcium phosphate cements with varying concentrations of IP6, in addition to their physical properties. Therefore cytocompatibility in vitro testing was performed using osteoblastic (MG-63) and osteoclastic (RAW 264.7 differentiated with RANKL) cells. We could demonstrate that the physical properties like the compressive strength of specimens formed with IP6 (brushite_IP6_5 = 11.2 MPa) were improved compared to the reference (brushite = 9.8 MPa). In osteoblast and osteoclast assays, IP6 exhibited significantly better cytocompatibility in terms of cell activity and cell number for brushite cements up to 11 times compared to the brushite reference. In contrast, the calcium-deficient hydroxyapatite (CDHA) cements produced similar results for IP6 (CDHA_IP6_0.25 = 27.0 MPa) when compared to their reference (CDHA = 21.2 MPa). Interestingly, lower doses of IP6 were found to be more effective than higher doses with up to 3 times higher. Additionally, IP6 significantly increased degradation in both passive and active resorption. For these reasons, IP6 is emerging as a strong new competitor to established setting retarders such as citric acid. These cements have potential applications in bone augmentation, the stabilisation of non-load bearing fractures (craniofacial), or the cementation of metal implants.


Assuntos
Cimentos Ósseos , Fosfatos de Cálcio , Teste de Materiais , Osteoblastos , Osteoclastos , Ácido Fítico , Ácido Fítico/química , Animais , Fosfatos de Cálcio/química , Camundongos , Cimentos Ósseos/química , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Células RAW 264.7 , Humanos , Osteoclastos/efeitos dos fármacos , Força Compressiva , Materiais Biocompatíveis/química , Durapatita/química
3.
Nat Commun ; 15(1): 5107, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877001

RESUMO

Inositol hexaphosphate (InsP6) is the major storage form of phosphorus in seeds. Reducing seed InsP6 content is a breeding objective in agriculture, as InsP6 negatively impacts animal nutrition and the environment. Nevertheless, how InsP6 accumulation is regulated remains largely unknown. Here, we identify a clade of receptor-like cytoplasmic kinases (RLCKs), named Inositol Polyphosphate-related Cytoplasmic Kinases 1-6 (IPCK1-IPCK6), deeply involved in InsP6 accumulation. The InsP6 concentration is dramatically reduced in seeds of ipck quadruple (T-4m/C-4m) and quintuple (C-5m) mutants, accompanied with the obviously increase of phosphate (Pi) concentration. The plasma membrane-localized IPCKs recruit IPK1 involved in InsP6 synthesis, and facilitate its binding and activity via phosphorylation of GRF 14-3-3 proteins. IPCKs also recruit IPK2s and PI-PLCs required for InsP4/InsP5 and InsP3 biosynthesis respectively, to form a potential IPCK-GRF-PLC-IPK2-IPK1 complex. Our findings therefore uncover a regulatory mechanism of InsP6 accumulation governed by IPCKs, shedding light on the mechanisms of InsP biosynthesis in eukaryotes.


Assuntos
Proteínas 14-3-3 , Proteínas de Arabidopsis , Arabidopsis , Ácido Fítico , Proteínas 14-3-3/metabolismo , Proteínas 14-3-3/genética , Ácido Fítico/metabolismo , Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Mutação , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Fosfatos de Inositol/metabolismo
4.
Parasite Immunol ; 46(5): e13040, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38801355

RESUMO

Cystic echinococcosis is caused by the tissue-dwelling larva (hydatid) of Echinococcus granulosus sensu lato. A salient feature is that this larva is protected by the acellular laminated layer (LL). As the parasite grows, the LL sheds abundant particles that can accumulate in the parasite's vicinity. The potential of LL particles to induce inflammation in vivo has not been specifically analysed. It is not known how each of its two major components, namely highly glycosylated mucins and calcium inositol hexakisphosphate (InsP6) deposits, impacts inflammation induced by the LL as a whole. In this work, we show that LL particles injected intraperitoneally cause infiltration of eosinophils, neutrophils and monocytes/macrophages as well as the disappearance of resident (large peritoneal) macrophages. Strikingly, the absence of calcium InsP6 enhanced the recruitment of all the inflammatory cell types analysed. In contrast, oxidation of the mucin carbohydrates caused decreased recruitment of neutrophils. The carbohydrate-oxidised particles caused cell influx nonetheless, which may be explained by possible receptor-independent effects of LL particles on innate immune cells, as suggested by previous works from our group. In summary, LL particles can induce acute inflammatory cell recruitment partly dependent on its mucin glycans, and this recruitment is attenuated by the calcium InsP6 component.


Assuntos
Echinococcus granulosus , Ácido Fítico , Animais , Echinococcus granulosus/imunologia , Ácido Fítico/farmacologia , Ácido Fítico/metabolismo , Equinococose/imunologia , Equinococose/parasitologia , Inflamação , Neutrófilos/imunologia , Mucinas/metabolismo , Camundongos , Macrófagos/imunologia , Macrófagos/metabolismo , Eosinófilos/imunologia , Feminino , Larva/imunologia
5.
ACS Nano ; 18(21): 13528-13537, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38747549

RESUMO

Dental caries is a widespread oral disease that poses a significant medical challenge. Traditional caries prevention methods, primarily the application of fluoride, often fall short in effectively destroying biofilms and preventing enamel demineralization, thereby providing limited efficacy in halting the progression of caries over time. To address this issue, we have developed a green and cost-effective synergistic strategy for the prevention of dental caries. By combining natural sodium phytate and chitosan, we have created chitosan-sodium phytate nanoparticles that offer both the antimicrobial properties of chitosan and the enamel demineralization-inhibiting capabilities of sodium phytate. In an ex vivo biofilm model of human teeth, we found that these nanoparticles effectively prevent biofilm buildup and acid damage to the mineralized tissue. Additionally, topical treatment of dental caries in rodent models has shown that these nanoparticles effectively suppress disease progression without negatively impacting oral microbiota diversity or causing harm to the gingival-mucosal tissues, unlike traditional prevention methods.


Assuntos
Biofilmes , Quitosana , Cárie Dentária , Nanopartículas , Ácido Fítico , Cárie Dentária/prevenção & controle , Quitosana/química , Quitosana/farmacologia , Humanos , Nanopartículas/química , Ácido Fítico/química , Ácido Fítico/farmacologia , Ácido Fítico/administração & dosagem , Animais , Biofilmes/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/administração & dosagem , Camundongos
6.
Int J Biol Macromol ; 269(Pt 2): 132135, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38719000

RESUMO

Here, a novel multifunctional coating containing bio-based phytic acid (PA), L-glutamic acid (L-Glu), and trimesoyl chloride (TMC) is constructed by a simple soaking strategy, giving cotton fabrics excellent flame retardancy, washability, and antibacterial properties. The coating layer on the cotton surface was prepared via the electrostatic and hydrogen bonding between PA and L-Glu, accompanied by the interface polymerization between PA, L-Glu, and TMC. Among them, the limiting oxygen index value of the treated cotton fabrics (C2 and C2-TMC) was as high as 40 %. During the vertical flammability test, both C2 and C2-TMC cotton showed self-extinguished behavior with a short damaged length (≤50 mm). Remarkably, the LOI of C2-TMC sustained a high value (30 %) even after 300 laundering cycles, maintaining its self-extinguishing behavior in the vertical combustion test. Additionally, in the cone calorimetry test, peak heat release rate and total heat release of treated cotton were lower than control cotton. Surprisingly, after 30 or 60 laundering cycles, the C2-TMC cotton exhibited excellent antibacterial activity against Escherichia coli, Staphylococcus aureus, and Candida albicans due to the continuous exposure of PA and L-Glu. Moreover, the coating layer on the cotton surface had little impact on the mechanical properties and feel of the fabric.


Assuntos
Fibra de Algodão , Retardadores de Chama , Ácido Fítico , Ácido Fítico/química , Ácido Fítico/farmacologia , Aminoácidos/química , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Têxteis , Testes de Sensibilidade Microbiana
7.
Sci Rep ; 14(1): 11908, 2024 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789472

RESUMO

Common beans are a common staple food with valuable nutritional qualities, but their high contents in antinutritional factors (ANFs) can decrease the bioavailability of (i) fat-soluble micronutrients including carotenoids and (ii) minerals. Our objective was to select ANF-poor bean lines that would not interfere with carotenoid and mineral bioavailability. To achieve this objective, seeds of commercial and experimental Phaseolus vulgaris L. bean lines were produced for 2 years and the bean's content in ANFs (saponins, phytates, tannins, total polyphenols) was assessed. We then measured carotenoid bioaccessibility and mineral solubility (i.e. the fraction of carotenoid and mineral that transfer into the aqueous phase of the digesta and is therefore absorbable) from prepared beans using in vitro digestion. All beans contained at least 200 mg/100 g of saponins and 2.44 mg/100 g tannins. The low phytic acid (lpa) lines, lpa1 and lpa12 exhibited lower phytate levels (≈ - 80%, p = 0.007 and p = 0.02) than their control BAT-93. However, this decrease had no significant impact on mineral solubility. HP5/1 (lpa + phaseolin and lectin PHA-E free) bean line, induced an improvement in carotenoid bioaccessibility (i.e., + 38%, p = 0.02, and + 32%, p = 0.005, for phytofluene bioaccessibility in 2021 and 2022, respectively). We conclude that decrease in the phytate bean content should thus likely be associated to decreases in other ANFs such as tannins or polyphenols to lead to significant improvement of micronutrient bioaccessibility.


Assuntos
Disponibilidade Biológica , Carotenoides , Minerais , Phaseolus , Ácido Fítico , Solubilidade , Taninos , Phaseolus/química , Phaseolus/metabolismo , Carotenoides/análise , Carotenoides/metabolismo , Ácido Fítico/análise , Minerais/análise , Taninos/análise , Sementes/química , Sementes/metabolismo , Polifenóis/análise , Valor Nutritivo , Saponinas/análise
8.
Chemosphere ; 358: 142226, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704039

RESUMO

Cellulosic substrates, including wood and thatch, have become icons for sustainable architecture and construction, however, they suffer from high flammability because of their inherent cellulosic composition. Current control measures for such hazards include applying intumescent fire-retardant (IFR) coatings that swell and form a char layer upon ignition, protecting the underlying substrate from burning. Typically, conventional IFR coatings are opaque and are made of halogenated compounds that release toxic fumes when ignited, compromising the roofing's aesthetic value and sustainability. In this work, phytic acid, a naturally occurring phosphorus source extracted from rice bran, was used to synthesize phytic acid-based fire-retardants (PFR) via esterification under reflux, along with powdered chicken eggshells (CES) as calcium carbonate (CaCO3) bio-filler. These components were incorporated into melamine formaldehyde resin to produce the transparent IFR coating. It was revealed that the developed IFR coatings achieved the highest fire protection rating based on UL94 flammability standards compared to the control. The coatings also yielded increased LOI values, indicative of self-extinguishing properties. A 17 °C elevation of the IFR coating's melting temperature and a significant ∼172% increase in enthalpy change from the control were observed, indicating enhanced fire-retardancy. The thermal stability of the coatings was improved, denoted by reduced mass losses, and increased residual masses after thermal degradation. As validated by microscopy and spectroscopy, the abundance of phosphorus and carbon groups in the coatings' condensed phase after combustion indicates enhanced char formation. In the gas phase, TG-FTIR showed the evolution of non-flammable CO2, and fire-retardant PO and P-O-C. Mechanical property testing confirmed no reduction in the adhesion strength of the IFR coating. With these results, the developed IFR coating exhibited enhanced fire-retardancy whilst remaining optically transparent, suggestive of a dual-phase IFR protective mechanism involving the release of gaseous combustion diluents and the formation of a thermally insulating char layer.


Assuntos
Casca de Ovo , Retardadores de Chama , Ácido Fítico , Casca de Ovo/química , Ácido Fítico/química , Animais , Incêndios , Celulose/química , Carbonato de Cálcio/química , Galinhas
9.
Int J Biol Macromol ; 270(Pt 1): 132260, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38734338

RESUMO

The utilization of bioderived flame retardants in biodegradable poly (lactic acid) (PLA) has profound practical implications for extending the widespread application of PLA composites and protecting the environment. Nevertheless, there are still certain challenges that require prompt attention, especially the ineffectiveness of bio-based flame retardants and their deterioration of the mechanical properties of PLA. This work introduced triglycidyl isocyanurate (TGIC), which has multiple epoxy functions, into the self-assembly process of phytic acid (PA) and chitosan (CS). The epoxy-modified bioderived flame retardant PA@CS-TGIC (PCT) was well dispersed in the PLA matrix and had a strong interfacial adhesion, while also TGIC had a synergistic char-forming effect. By compounding epoxy-modified ammonium polyphosphate (MAPP), 3%PCT/MAPP-PLA composites may reach a LOI value of 28.8 % and UL-94 V-0 rating. Simultaneously, the melting droplets had been considerably reduced. Tensile strength of the 3%PCT/MAPP-PLA composites was 67.0 MPa, 10.8 % higher than that of pure PLA. This work paves a new avenue for the development of PLA composites with robust mechanical and flame retardant properties.


Assuntos
Retardadores de Chama , Poliésteres , Poliésteres/química , Resistência à Tração , Quitosana/química , Ácido Fítico/química , Triazinas/química
10.
Int J Biol Macromol ; 269(Pt 1): 131985, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692538

RESUMO

Polylactic acid (PLA) is a promising renewable polymer material with excellent biodegradability and good mechanical properties. However, the easy flammability and slow natural degradation limited its further applications, especially in high-security fields. In this work, a fully bio-based intumescent flame-retardant system was designed to reduce the fire hazard of PLA. Firstly, arginine (Arg) and phytic acid (PA) were combined through electrostatic ionic interaction, followed by the introduction of starch as a carbon source, namely APS. The UL-94 grade of PLA/APS composites reached V-0 grade by adding 3 wt% of APS and exhibited excellent anti-dripping performance. With APS addition increasing to 7 wt%, LOI value increased to 26 % and total heat release decreased from 58.4 (neat PLA) to 51.1 MJ/m2. Moreover, the addition of APS increased its crystallinity up to 83.5 % and maintained the mechanical strength of pristine PLA. Noteworthy, APS accelerated the degradation rate of PLA under submerged conditions. Compared with pristine PLA, PLA/APS showed more apparent destructive network morphology and higher mass and Mn loss, suggesting effective degradation promotion. This work provides a full biomass modification strategy to construct renewable plastic with both good flame retardancy and high degradation efficiency.


Assuntos
Incêndios , Retardadores de Chama , Poliésteres , Poliésteres/química , Incêndios/prevenção & controle , Ácido Fítico/química , Química Verde/métodos , Arginina/química
11.
Int J Biol Macromol ; 269(Pt 1): 132080, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705314

RESUMO

Theranostic antibacterial wound dressing is highly recommended in practical applications. The conventional methods of integrating diagnostic and therapeutic functions have the disadvantages of complicated preparation, mutual interference, inability to effectively broad spectrum antibacterial property, and easy to induce drug-resistant bacteria. Herein, a pH and light-responsive theranostic antibacterial hydrogel is developed by biopolymers polyvinyl alcohol (PVA) and polyaniline (PANI), and cross-linking with phytic acid (PA), which is widely present in rice bran. The biological polymer-based conductive hydrogel enables timely diagnosis and photothermal sterilization in-situ for wound healing. Because PANI is highly sensitive to pH changes in the bacterial microenvironment, the hydrogel can detect bacterial infections at concentrations as low as 103 CFU/mL. Subsequently, PANI absorbs near-infrared light to achieve on-demand exothermic sterilization (under 808 nm irradiation for 20 min, the killing ratios for Staphylococcus aureus and Escherichia coli reached almost 100 %). In addition, the hydrogel can monitor the intensity of joint movement to avoid wound re-tearing sensitively. In vitro cytotoxicity and hemocompatibility experiments and in vivo full-thickness infected wound model indicate that the hydrogel has good biocompatibility, antibacterial ability, and can accelerate the wound healing effectively. This work will promote the development of wearable electronic devices and precision medicine.


Assuntos
Antibacterianos , Escherichia coli , Hidrogéis , Oryza , Ácido Fítico , Staphylococcus aureus , Cicatrização , Ácido Fítico/química , Ácido Fítico/farmacologia , Cicatrização/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Hidrogéis/química , Hidrogéis/farmacologia , Oryza/química , Staphylococcus aureus/efeitos dos fármacos , Animais , Escherichia coli/efeitos dos fármacos , Biopolímeros/química , Biopolímeros/farmacologia , Nanomedicina Teranóstica , Camundongos , Humanos , Álcool de Polivinil/química , Compostos de Anilina/química , Compostos de Anilina/farmacologia
12.
ACS Appl Bio Mater ; 7(5): 3283-3294, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38727030

RESUMO

Medical implants are constantly facing the risk of bacterial infections, especially infections caused by multidrug resistant bacteria. To mitigate this problem, gold nanoparticles with alkyl bromide moieties (Au NPs-Br) on the surfaces were prepared. Xenon light irradiation triggered the plasmon effect of Au NPs-Br to induce free radical graft polymerization of 2-(dimethylamino)ethyl methacrylate (DMAEMA), leading to the formation of poly(DMAEMA) brush-grafted Au NPs (Au NPs-g-PDM). The Au NPs-g-PDM nanocomposites were conjugated with phytic acid (PA) via electrostatic interaction and van der Waals interaction. The as-formed aggregates were deposited on the titanium (Ti) substrates to form the PA/Au NPs-g-PDM (PAP) hybrid coatings through surface adherence of PA and the gravitational effect. Synergistic bactericidal effects of contact-killing caused by the cationic PDM brushes, and local heating generated by the Au NPs under near-infrared irradiation, conferred strong antibacterial effects on the PAP-deposited Ti (Ti-PAP) substrates. The synergistic bactericidal effects reduced the threshold temperature required for the photothermal sterilization, which in turn minimized the secondary damage to the implant site. The Ti-PAP substrates exhibited 97.34% and 99.97% antibacterial and antiadhesive efficacy, respectively, against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), compared to the control under in vitro antimicrobial assays. Furthermore, the as-constructed Ti-PAP surface exhibited a 99.42% reduction in the inoculated S. aureus under in vivo assays. In addition, the PAP coatings exhibited good biocompatibility in the hemolysis and cytotoxicity assays as well as in the subcutaneous implantation of rats.


Assuntos
Antibacterianos , Escherichia coli , Ouro , Teste de Materiais , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Ácido Fítico , Staphylococcus aureus , Ouro/química , Ouro/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Nanopartículas Metálicas/química , Ácido Fítico/química , Ácido Fítico/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Animais , Propriedades de Superfície , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Cátions/química , Cátions/farmacologia , Polímeros/química , Polímeros/farmacologia , Titânio/química , Titânio/farmacologia
13.
Int J Biol Macromol ; 271(Pt 1): 132673, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38821804

RESUMO

Smart textiles with flame retardant and fire-warning functions have received more and more attention. However, improving the fire-warning response sensitivity and long-term responsiveness of the smart textiles is a top priority. In this research, flame retardant and fire-warning cotton fabrics were prepared by layer-by-layer assembly composite coating consisting of bio-based flame retardants composed of chitosan (CS) and phytic acid (PA) and carbon-based nanomaterials composed of carbon nanotubes (CNTs) and graphene oxide (GO). The PA-GO/CS-CNTs coated cotton fabric showed excellent flame retardancy with a limiting oxygen index (LOI) value of 31 %, and the coated fabrics could self-extinguish rapidly when the flame was removed. The fire hazard of the coated fabric was significantly reduced by reducing the 45.77 % of peak heat release rate, 29.69 % of total heat release and 81.9 % of total smoke production. The PA-GO/CS-CNTs coated cotton fabric showed ultra-fast fire warning response with the response time of 1.0 s. And the fire-warning response time of the coated cotton fabric could last longer than 600 s revealing it possessed the continuous fire warning response property. This research provides a new strategy to prepare the smart fireproof textiles with flame retardant and fire-warning functions to broaden its application in early fire-warning.


Assuntos
Quitosana , Fibra de Algodão , Retardadores de Chama , Grafite , Nanotubos de Carbono , Quitosana/química , Grafite/química , Nanotubos de Carbono/química , Têxteis , Incêndios/prevenção & controle , Ácido Fítico/química
14.
Plant Physiol Biochem ; 211: 108723, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38749376

RESUMO

Legume-rhizobia symbiosis requires high phosphorus (P) in the form of ATP to convert atmospheric nitrogen (N) into ammonia. The fixed ammonia is converted to NH4+ by H+-ATPase via protonation. To the best of our knowledge, most of these research works resort to using only inorganic P (Pi) to the neglect of the organic P (Po) counterpart. As it stands, the potential regulating roles of plasma membrane (PM) H+-ATPases during legume-rhizobia symbiosis in response to phytic acid supply and how it alters and modulates the regulation of PM H+-ATPases remain obscure. To contribute to the above hypothesis, we investigate the mechanisms that coordinately facilitate the growth, uptake, and transcript expression of PM H+-ATPase gene isoforms in response to different P sources when hydroponically grown Vicia faba plants were exposed to three P treatments, viz., low- and high-Pi (2.0 and 200 µM KH2PO4; LPi and HPi), and phytic acid (200 µM; Po) and inoculated with Rhizobium leguminosarum bv. viciae 384 for 30 days. The results consistently reveal that the supply of Po improved not only the growth and biomass, but also enhanced photosynthetic parameters, P uptake and phosphatase activities in symbiotically grown Vicia faba relative to Pi. The supply of Po induced higher transcriptional expression of all PM H+-ATPase gene isoforms, with possible interactions between phosphatases and H+-ATPase genes in Vicia faba plants when exclusively reliant on N derived from nodule symbiosis. Overall, preliminary results suggest that Po could be used as an alternative nutrition in symbiotic crops to improve plant growth.


Assuntos
Ácido Fítico , Simbiose , Vicia faba , Ácido Fítico/metabolismo , Vicia faba/metabolismo , Vicia faba/genética , Regulação da Expressão Gênica de Plantas , Rhizobium leguminosarum/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , ATPases Translocadoras de Prótons/metabolismo , ATPases Translocadoras de Prótons/genética , Fósforo/metabolismo
15.
J Colloid Interface Sci ; 668: 678-690, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38710124

RESUMO

Aerogels, as a unique porous material, are expected to be used as insulation materials to solve the global environmental and energy crisis. Using chitosan, citric acid, pectin and phytic acid as raw materials, an all-biomass-based aerogel with high modulus was prepared by the triple strategy of ionic, physical and chemical cross-linking through directional freezing technique. Based on this three-dimensional network, the aerogel exhibited excellent compressive modulus (24.89 ± 1.76 MPa) over a wide temperature range and thermal insulation properties. In the presence of chitosan, citric acid and phytic acid, the aerogel obtained excellent fire safety (LOI value up to 31.2%) and antibacterial properties (antibacterial activity against Staphylococcus aureus and Escherichia coli reached 81.98% and 67.43%). In addition, the modified aerogel exhibited excellent hydrophobicity (hydrophobic angle of 146°) and oil-water separation properties. More importantly, the aerogel exhibited a biodegradation rate of up to 40.31% for 35 days due to its all-biomass nature. This work provides a green and sustainable strategy for the production of highly environmentally friendly thermal insulation materials with high strength, flame retardant, antibacterial and hydrophobic properties.


Assuntos
Antibacterianos , Quitosana , Ácido Cítrico , Escherichia coli , Géis , Staphylococcus aureus , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Géis/química , Quitosana/química , Ácido Cítrico/química , Biomassa , Interações Hidrofóbicas e Hidrofílicas , Porosidade , Ácido Fítico/química , Pectinas/química , Reagentes de Ligações Cruzadas/química , Testes de Sensibilidade Microbiana , Propriedades de Superfície , Tamanho da Partícula , Temperatura
16.
Food Res Int ; 186: 114321, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729691

RESUMO

Biogenic nanoparticles are promising carriers to deliver essential minerals. Here, calcium-enriched polyphosphate nanoparticles (CaPNPs) with a Ca/P molar ratio > 0.5 were produced by Synechococcus sp. PCC 7002 in the growth medium containing 1.08 g/L CaCl2, and had nearly spherical morphologies with a wide size distribution of 5-75 nm and strongly anionic surface properties with an average ζ-potential of -39 mV, according to dynamic light-scattering analysis, transmission and scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The ex-vivo ligated mouse ileal loop assays found that calcium in CaPNPs was readily available to intestinal absorption via both ion channel-mediated and endocytic pathways, specifically invoking macropinocytic internalization, lysosomal degradation, and transcytosis. Rat oral pharmacokinetics revealed that CaPNPs had a calcium bioavailability approximately 100 % relative to that of CaCl2 and more than 1.6 times of that of CaCO3. CaPNPs corrected the retinoic acid-induced increase in serum calcium, phosphorus, and bone-specific alkaline phosphatase, and decrease in serum osteocalcin, bone mineral content/density, and femoral geometric parameters with an efficacy equivalent to CaCl2 and markedly greater than CaCO3. In contrast to CaCl2, CaPNPs possessed desirable resistance against phytate's antagonistic action on calcium absorption in these ex vivo and in vivo studies. Overall, CaPNPs are attractive as a candidate agent for calcium supplementation, especially to populations on high-phytate diets.


Assuntos
Disponibilidade Biológica , Cálcio , Microalgas , Nanopartículas , Ácido Fítico , Polifosfatos , Animais , Polifosfatos/química , Camundongos , Ácido Fítico/química , Cálcio/metabolismo , Masculino , Ratos , Absorção Intestinal/efeitos dos fármacos , Ratos Sprague-Dawley
17.
AAPS PharmSciTech ; 25(5): 106, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724834

RESUMO

The primary factor underlying the virulence of Candida albicans is its capacity to form biofilms, which in turn leads to recurrent complications. Over-the-counter antifungal treatments have proven ineffective in eliminating fungal biofilms and the inflammatory cytokines produced during fungal infections. Chitosan nanoparticles offer broad and versatile therapeutic potential as both antifungal agents and carriers for antifungal drugs to combat biofilm-associated Candida infections. In our study, we endeavoured to develop chitosan nanoparticles utilising chitosan and the antifungal crosslinker phytic acid targeting C. albicans. Phytic acid, known for its potent antifungal and anti-inflammatory properties, efficiently crosslinks with chitosan. The nanoparticles were synthesised using the ionic gelation technique and subjected to analyses including Fourier transform infrared spectroscopy, dynamic light scattering, and zeta potential analysis. The synthesised nanoparticles exhibited dimensions with a diameter (Dh) of 103 ± 3.9 nm, polydispersity index (PDI) of 0.33, and zeta potential (ZP) of 37 ± 2.5 mV. These nanoparticles demonstrated an antifungal effect with a minimum inhibitory concentration (MIC) of 140 ± 2.2 µg/mL, maintaining cell viability at approximately 90% of the MIC value and reducing cytokine levels. Additionally, the nanoparticles reduced ergosterol content and exhibited a 62% ± 1.2 reduction in biofilm susceptibility, as supported by colony-forming unit (CFU) and XTT assays-furthermore, treatment with nanoparticles reduced exopolysaccharide production and decreased secretion of aspartyl protease by C. albicans. Our findings suggest that the synthesised nanoparticles effectively combat Candida albicans infections. In vivo studies conducted on a mouse model of vaginal candidiasis confirmed the efficacy of the nanoparticles in combating fungal infections in vivo.


Assuntos
Antifúngicos , Biofilmes , Candida albicans , Quitosana , Testes de Sensibilidade Microbiana , Nanopartículas , Ácido Fítico , Quitosana/química , Biofilmes/efeitos dos fármacos , Nanopartículas/química , Antifúngicos/farmacologia , Antifúngicos/administração & dosagem , Animais , Candida albicans/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana/métodos , Ácido Fítico/farmacologia , Ácido Fítico/administração & dosagem , Ácido Fítico/química , Feminino , Candidíase/tratamento farmacológico , Tamanho da Partícula , Portadores de Fármacos/química , Reagentes de Ligações Cruzadas/química , Citocinas/metabolismo
18.
J Food Sci ; 89(5): 2557-2566, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38578119

RESUMO

Black lentils contain protein, carbohydrates, dietary fiber, minerals, and vitamins, as well as phytochemicals and various bioactive compounds. Ultraviolet (UV) radiation and ultrasound (US) methods are innovative technologies that can be used to increase the efficiency of the germination process in grains and legumes. To improve the nutritional value and bioactive compounds of the cookies, black lentils germinated by applying UV radiation and US technology were used in the cookie formulation. Before the germination process, UV, US, and their combination (UV+US) were applied, and pretreated and unpretreated germinated black lentil flours were used at a level of 20% in the cookie formulation. The results revealed that pretreatment application increased the total phenolic content and antioxidant activity more than the lentil sample germinated without any treatment. In addition, the pretreatments applied further reduced the amount of phytic acid in black lentils and the lowest phytic acid content was obtained with the UV-US combination. Compared to cookies containing unpretreated germinated black lentil flour, higher L* values and lower a* values were obtained in the cookie samples containing pretreated germinated black lentil flour. Cookies containing all pretreated germinated lentils generally exhibited higher Ca and K content. This study demonstrated that UV radiation and US improved the nutritional value and bioactive components of the germinated black lentil flour and the cookies in which it was used, compared to the black lentils germinated without any treatment. PRACTICAL APPLICATION: Pretreatment of black lentils with UV/US application before germination resulted in a greater increase in total phenolic content and antioxidant activity compared to the control sample. The applied pretreatments caused a further decrease in the amount of phytic acid in black lentil samples. Black lentils germinated with the UV+US combination revealed higher Ca, Fe, K, and Mg content compared to the sample germinated without any treatment.


Assuntos
Antioxidantes , Germinação , Lens (Planta) , Valor Nutritivo , Fenóis , Ácido Fítico , Sementes , Raios Ultravioleta , Lens (Planta)/química , Lens (Planta)/efeitos da radiação , Germinação/efeitos da radiação , Antioxidantes/análise , Antioxidantes/farmacologia , Ácido Fítico/análise , Sementes/química , Sementes/efeitos da radiação , Fenóis/análise , Manipulação de Alimentos/métodos , Farinha/análise , Ultrassom/métodos
19.
Protein Expr Purif ; 220: 106489, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38685535

RESUMO

Phytate (inositol hexaphosphate) is the major storage form of phosphorus (P) in nature, and phytases catalyze the hydrolysis of P from phytate and the formation of inositol phosphate isomers. In this study, a bacterium that produces phytase was isolated in a phytase screening medium. The bacterium was identified as Klebsiella sp. using phenotypic and molecular techniques. The PhyK phytase gene was successfully amplified from the genome, inserted into the pET-21a (+) vector, and expressed as a recombinant protein in E. Coli BL21. The efficiency of a laboratory phytase (Lab-Ph, PhyK phytase) was determined and compared with a commercial phytase (Com-Ph, Quantum Blue 40P phytase, AB Vista) under an in vitro digestion assay. The native signal peptide effectively facilitated the translocation of the protein to the periplasmic space of E. Coli BL21, resulting in the proper folding of the protein and the manifestation of desirable enzyme activity. The Lab-Ph displayed the temperature and pH optima at 50 °C and 5 respectively. In addition, the Lab-Ph was inactivated at 80 °C. Under an in vitro digestion assay condition, Lab-Ph improved the P solubility coefficient in broiler diets. In comparison, the Com-Ph significantly increased the P solubility coefficient even when compared with the Lab-Ph. In summary, this study has shown that Lab-Ph possesses the necessary biochemical properties to be used in various industrial applications. However, Lab-Ph is extremely sensitive to heat treatment. The Lab-Ph and Com-Ph under an in vitro digestion assay improved the solubility coefficient of P in the broiler diet.


Assuntos
6-Fitase , Galinhas , Escherichia coli , Klebsiella , Proteínas Recombinantes , Solubilidade , Animais , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , 6-Fitase/genética , 6-Fitase/química , 6-Fitase/metabolismo , Klebsiella/genética , Klebsiella/enzimologia , Escherichia coli/genética , Escherichia coli/metabolismo , Ração Animal , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Concentração de Íons de Hidrogênio , Minerais/metabolismo , Minerais/química , Ácido Fítico/metabolismo , Ácido Fítico/química
20.
Biochemistry ; 63(9): 1097-1106, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38669178

RESUMO

As a key component for NADPH oxidase 2 (NOX2) activation, the peripheral membrane protein p47phox translocates a cytosolic activating complex to the membrane through its PX domain. This study elucidates a potential regulatory mechanism of p47phox recruitment and NOX2 activation by inositol hexaphosphate (IP6). Through NMR, fluorescence polarization, and FRET experimental results, IP6 is shown to be capable of breaking the lipid binding and membrane anchoring events of p47phox-PX with low micromolar potency. Other phosphorylated inositol species such as IP5(1,3,4,5,6), IP4(1,3,4,5), and IP3(1,3,4) show weaker binding and no ability to inhibit lipid interactions in physiological concentration ranges. The low micromolar potency of IP6 inhibition of the p47phox membrane anchoring suggests that physiologically relevant concentrations of IP6 serve as regulators, as seen in other membrane anchoring domains. The PX domain of p47phox is known to be promiscuous to a variety of phosphatidylinositol phosphate (PIP) lipids, and this regulation may help target the domain only to the membranes most highly enriched with the highest affinity PIPs, such as the phagosomal membrane, while preventing aberrant binding to other membranes with high and heterogeneous PIP content, such as the plasma membrane. This study provides insight into a potential novel regulatory mechanism behind NOX2 activation and reveals a role for small-molecule regulation in this important NOX2 activator.


Assuntos
NADPH Oxidases , Ácido Fítico , Ácido Fítico/metabolismo , Ácido Fítico/química , NADPH Oxidases/metabolismo , NADPH Oxidases/antagonistas & inibidores , Humanos , Membrana Celular/metabolismo , NADPH Oxidase 2/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo
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