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1.
J Biol Chem ; 299(7): 104910, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37315789

RESUMO

Protein A affinity chromatography is widely used for the large-scale purification of antibodies because of its high yield, selectivity, and compatibility with NaOH sanitation. A general platform to produce robust affinity capture ligands for proteins beyond antibodies would improve bioprocessing efficiency. We previously developed nanoCLAMPs (nano Clostridial Antibody Mimetic Proteins), a class of antibody mimetic proteins useful as lab-scale affinity capture reagents. This work describes a protein engineering campaign to develop a more robust nanoCLAMP scaffold compatible with harsh bioprocessing conditions. The campaign generated an improved scaffold with dramatically improved resistance to heat, proteases, and NaOH. To isolate additional nanoCLAMPs based on this scaffold, we constructed a randomized library of 1 × 1010 clones and isolated binders to several targets. We then performed an in-depth characterization of nanoCLAMPs recognizing yeast SUMO, a fusion partner used for the purification of recombinant proteins. These second-generation nanoCLAMPs typically had a Kd of <80 nM, a Tm of >70 °C, and a t1/2 in 0.1 mg/ml trypsin of >20 h. Affinity chromatography resins bearing these next-generation nanoCLAMPs enabled single-step purifications of SUMO fusions. Bound target proteins could be eluted at neutral or acidic pH. These affinity resins maintained binding capacity and selectivity over 20 purification cycles, each including 10 min of cleaning-in-place with 0.1 M NaOH, and remained functional after exposure to 100% DMF and autoclaving. The improved nanoCLAMP scaffold will enable the development of robust, high-performance affinity chromatography resins against a wide range of protein targets.


Assuntos
Anticorpos , Afinidade de Anticorpos , Cromatografia de Afinidade , Ligantes , Mimetismo Molecular , Engenharia de Proteínas , Proteínas Recombinantes , Anticorpos/química , Anticorpos/imunologia , Anticorpos/metabolismo , Cromatografia de Afinidade/métodos , Engenharia de Proteínas/métodos , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Hidróxido de Sódio/farmacologia , Estabilidade Proteica/efeitos dos fármacos , Temperatura Alta , Tripsina/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/metabolismo , Ligação Proteica
2.
Cytokine ; 175: 156502, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38237388

RESUMO

BACKGROUND: Hyperuricemia has been shown to be an inducer of pro-inflammatory mediators by human primary monocytes. To study the deleterious effects of hyperuricemia, a reliable and stable in vitro model using soluble urate is needed. One recent report showed different urate-dissolving methods resulted in either pro-inflammatory or anti-inflammatory properties. The aim of this study was to compare the effect of two methods of dissolving urate on both primary human peripheral blood mononuclear cells (PBMCs) and THP-1 cells. The two methods tested were 'pre-warming' and 'dissolving with NaOH'. METHODS: Primary human PBMCs and THP-1 cells were exposed to urate solutions, prepared using the two methodologies: pre-warming and dissolving with NaOH. Afterwards, cells were stimulated with various stimuli, followed by the measurement of the inflammatory mediators IL-1ß, IL-6, IL-1Ra, TNF, IL-8, and MCP-1. RESULTS: In PBMCs, we observed an overall pro-inflammatory effect of urate, both in the pre-warming and the NaOH dissolving method. A similar pro-inflammatory effect was seen in THP-1 cells for both dissolving methods after restimulation. However, THP-1 cells exhibited pro-inflammatory profile with exposure to urate alone without restimulation. We did not find MSU crystals in our cellular assays. CONCLUSIONS: Overall, the urate dissolving methods do not have critical impact on its inflammatory properties. Soluble urate prepared using either of the two methods showed mostly pro-inflammatory effects on human primary PBMCs and monocytic cell line THP-1. However, human primary PBMCs and the THP-1 differ in their response to soluble urate without restimulation.


Assuntos
Hiperuricemia , Ácido Úrico , Humanos , Ácido Úrico/farmacologia , Ácido Úrico/metabolismo , Hiperuricemia/metabolismo , Leucócitos Mononucleares/metabolismo , Hidróxido de Sódio/metabolismo , Hidróxido de Sódio/farmacologia , Monócitos , Mediadores da Inflamação/metabolismo
3.
Exp Eye Res ; 244: 109949, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38815791

RESUMO

PURPOSE: The current study used various techniques to develop a rabbit animal model of lacrimal gland damage caused by scarring conjunctivitis in the periglandular area. METHODS: Left eyes of New Zealand white rabbits were injected with 0.1 ml of 1M NaOH subconjunctivally around superior and inferior lacrimal gland orifices (Group 1, n = 4), touched with 1M NaOH for 100 s to the superior and inferior fornices with conjunctival denuding (Group 2; n = 4), and electrocauterization to the ductal opening area (Group 3; n = 4). The ocular surface staining, Schirmer I, lacrimal gland, and conjunctival changes were observed at baseline,1, 4, 8, and 12 weeks. The degree of glandular inflammation, conjunctival fibrosis (Masson Trichrome), and goblet cell density (PAS) were also assessed. RESULTS: At 12 weeks, the lacrimal glands of group 1 rabbits with periglandular injection showed severe inflammation with mean four foci/10HPF and a significant mean reduction in the Schirmer values by 7.6 mm (P = 0.007). Lacrimal glands had diffuse acinar atrophy, loss of myoepithelial cells, and ductular dilatation. The overlying conjunctiva showed fibrosis, goblet cell loss, and corneal vascularization in the inferotemporal quadrant. No lacrimal gland or ocular surface changes were observed in groups 2 and 3 at 12 weeks, except for localized subconjunctival fibrosis. CONCLUSION: Periglandular injection of 0.1 ml of 1M NaOH induced extensive lacrimal gland damage with reduced secretion and scarring in the subconjunctival plane compared to direct cauterization or direct NaOH contact to the ductal orifices of the rabbit lacrimal gland.


Assuntos
Cicatriz , Túnica Conjuntiva , Conjuntivite , Modelos Animais de Doenças , Síndromes do Olho Seco , Células Caliciformes , Lágrimas , Animais , Coelhos , Síndromes do Olho Seco/metabolismo , Cicatriz/patologia , Células Caliciformes/patologia , Túnica Conjuntiva/patologia , Lágrimas/metabolismo , Conjuntivite/patologia , Aparelho Lacrimal/patologia , Hidróxido de Sódio/toxicidade , Fibrose , Masculino , Contagem de Células , Feminino , Eletrocoagulação
4.
Exp Eye Res ; 244: 109948, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38815790

RESUMO

Severe corneal injury can lead to blindness even after prompt treatment. 14-3-3zeta, a member of an adaptor protein family, contributes to tissue repair by enhancing cellular viability and inhibiting fibrosis and inflammation in renal disease or arthritis. However, its role in corneal regeneration is less studied. In this study, filter disc of 2-mm diameter soaked in sodium hydroxide with a concentration of 0.5 N was placed at the center of the cornea for 30 s to establish a mouse model of corneal alkali injury. We found that 14-3-3zeta, which is mainly expressed in the epithelial layer, was upregulated following injury. Overexpression of 14-3-3zeta in ocular tissues via adeno-associated virus-mediated subconjunctival delivery promoted corneal wound healing, showing improved corneal structure and transparency. In vitro studies on human corneal epithelial cells showed that 14-3-3zeta was critical for cell proliferation and migration. mRNA-sequencing in conjunction with KEGG analysis and validation experiments revealed that 14-3-3zeta regulated the mRNA levels of ITGB1, PIK3R1, FGF5, PRKAA1 and the phosphorylation level of Akt, suggesting the involvement of the PI3K-Akt pathway in 14-3-3zeta-mediated tissue repair. 14-3-3zeta is a potential novel therapeutic candidate for treating severe corneal injury.


Assuntos
Proteínas 14-3-3 , Queimaduras Químicas , Proliferação de Células , Lesões da Córnea , Modelos Animais de Doenças , Queimaduras Oculares , Cicatrização , Cicatrização/efeitos dos fármacos , Cicatrização/fisiologia , Animais , Proteínas 14-3-3/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/biossíntese , Lesões da Córnea/metabolismo , Lesões da Córnea/patologia , Lesões da Córnea/genética , Camundongos , Queimaduras Oculares/induzido quimicamente , Queimaduras Químicas/metabolismo , Queimaduras Químicas/patologia , Queimaduras Químicas/tratamento farmacológico , Homeostase , Humanos , Epitélio Corneano/metabolismo , Epitélio Corneano/efeitos dos fármacos , Epitélio Corneano/lesões , Movimento Celular , Camundongos Endogâmicos C57BL , Masculino , Hidróxido de Sódio , Células Cultivadas , Regulação da Expressão Gênica , Western Blotting
5.
Mol Pharm ; 21(7): 3395-3406, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38836777

RESUMO

The incorporation of a counterion into an amorphous solid dispersion (ASD) has been proven to be an attractive strategy to improve the drug dissolution rate. In this work, the generality of enhancing the dissolution rates of free acid ASDs by incorporating sodium hydroxide (NaOH) was studied by surface-area-normalized dissolution. A set of diverse drug molecules, two common polymer carriers (copovidone or PVPVA and hydroxypropyl methylcellulose acetate succinate or HPMCAS), and two sample preparation methods (rotary evaporation and spray drying) were investigated. When PVPVA was used as the polymer carrier for the drugs in this study, enhancements of dissolution rates from 7 to 78 times were observed by the incorporation of NaOH into the ASDs at a 1:1 molar ratio with respect to the drug. The drugs having lower amorphous solubilities showed greater enhancement ratios, providing a promising path to improve the drug release performance from their ASDs. Samples generated by rotary evaporation and spray drying demonstrated comparable dissolution rates and enhancements when NaOH was added, establishing a theoretical foundation to bridge the ASD dissolution performance for samples prepared by different solvent-removal processes. In the comparison of polymer carriers, when HPMCAS was applied in the selected system (indomethacin ASD), a dissolution rate enhancement of 2.7 times by the incorporated NaOH was observed, significantly lower than the enhancement of 53 times from the PVPVA-based ASD. This was attributed to the combination of a lower dissolution rate of HPMCAS and the competition for NaOH between IMC and HPMCAS. By studying the generality of enhancing ASD dissolution rates by the incorporation of counterions, this study provides valuable insights into further improving drug release from ASD formulations of poorly water-soluble drugs.


Assuntos
Liberação Controlada de Fármacos , Metilcelulose , Hidróxido de Sódio , Solubilidade , Hidróxido de Sódio/química , Metilcelulose/química , Metilcelulose/análogos & derivados , Polímeros/química , Portadores de Fármacos/química , Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Pirrolidinas/química
6.
Biomacromolecules ; 25(3): 1738-1748, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38340076

RESUMO

Physical hydrogels of natural polysaccharides are considered as ideal candidates for wound dressing due to their natural biological activity and no harmful cross-linking agents. However, it remains a challenge to fabricate such hydrogel dressings in a facile and low-cost way. Herein, we reported an easy and cost-effective method to construct CO2-mediated alkali-neutralization Curdlan (CR) hydrogels without using an external cross-linking agent. Two types of hydrogels (denoted as CR-NaOH and CR-Na3PO4, respectively) were fabricated by dissolving CR powders in a NaOH or Na3PO4 aqueous solution, followed by keeping the CR alkaline solutions in air. The obtained pure CR hydrogels possessed a tunable porous structure with walls containing different forms of nanofibrils. These hydrogels exhibited much higher gel strength by comparison with the gels prepared by conventional heating treatment. They were flexible, stretchable, twistable, and conformable to arbitrarily curved skins. Moreover, they exhibited ideal swellability, proper degradability, and water vapor transmission rate, and their physicochemical properties were closely related to CR concentration in the alkaline solution. These two hydrogels also supported the growth of L929 cells. Importantly, studies on wound healing revealed that both 3CR-NaOH and 3CR-Na3PO4 hydrogels were capable of accelerating the wound healing process through recruiting more macrophages/fibroblasts, inducing more collagen deposition and neovascularization (α-SMA and CD31) without carrying any exogenous bioactive components. In conclusion, the present work not only reported promising materials for application in wound therapy but also offered a facile and safe manufacturing procedure for generating pure CR physical hydrogels with better performance.


Assuntos
Dióxido de Carbono , Hidrogéis , beta-Glucanas , Hidrogéis/farmacologia , Hidrogéis/química , Hidróxido de Sódio/farmacologia , Cicatrização , Antibacterianos/farmacologia
7.
Eur Biophys J ; 53(4): 225-238, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38613566

RESUMO

Calibration of titration calorimeters is an ongoing problem, particularly with calorimeters with reaction vessel volumes < 10 mL in which an electrical calibration heater is positioned outside the calorimetric vessel. Consequently, a chemical reaction with a known enthalpy change must be used to accurately calibrate these calorimeters. This work proposes the use of standard solutions of potassium acid phthalate (KHP) titrated into solutions of excess sodium hydroxide (NaOH) or excess tris(hydroxymethyl)aminomethane (TRIS) as standard reactions to determine the collective accuracy of the relevant variables in a determination of the molar enthalpy change for a reaction. KHP is readily available in high purity, weighable for easy preparation of solutions with accurately known concentrations, stable in solution, not compromised by side reactions with common contaminants such as atmospheric CO2, and non-corrosive to materials used in calorimeter construction. Molar enthalpy changes for these reactions were calculated from 0 to 60 °C from reliable literature data for the pKa of KHP, the molar enthalpy change for protonation of TRIS, and the molar enthalpy change for ionization of water. The feasibility of using these reactions as enthalpic standards was tested in several calorimeters; a 50 mL CSC 4300, a 185 µL NanoITC, a 1.4 mL VP-ITC, and a TAM III with 1 mL reaction vessels. The results from the 50 mL CSC 4300, which was accurately calibrated with an electric heater, verified the accuracy of the calculated standard values for the molar enthalpy changes of the proposed reactions.


Assuntos
Calorimetria , Hidróxido de Sódio , Trometamina , Hidróxido de Sódio/química , Calibragem , Trometamina/química , Temperatura , Padrões de Referência , Termodinâmica
8.
Microb Cell Fact ; 23(1): 106, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600576

RESUMO

BACKGROUND: The textile industry has several negative impacts, mainly because it is based on a linear business model that depletes natural resources and produces excessive amounts of waste. Globally, about 75% of textile waste is disposed of in landfills and only 25% is reused or recycled, while less than 1% is recycled back into new garments. In this study, we explored the valorisation of cotton fabric waste from an apparel textile manufacturing company as valuable biomass to produce lactic acid, a versatile chemical building block. RESULTS: Post-industrial cotton patches were pre-treated with the aim of developing a methodology applicable to the industrial site involved. First, a mechanical shredding machine reduced the fabric into individual fibres of maximum 35 mm in length. Afterwards, an alkaline treatment was performed, using NaOH at different concentrations, including a 16% (w/v) NaOH enriched waste stream from the mercerisation of cotton fabrics. The combination of chemo-mechanical pre-treatment and enzymatic hydrolysis led to the maximum recovery yield of 90.46 ± 3.46%, corresponding to 74.96 ± 2.76 g/L of glucose released, which represents a novel valorisation of two different side products (NaOH enriched wastewater and cotton textile waste) of the textile industry. The Saccharomyces cerevisiae strain CEN.PK m850, engineered for redirecting the natural alcoholic fermentation towards a homolactic fermentation, was then used to valorise the glucose-enriched hydrolysate into lactic acid. Overall, the process produced 53.04 g/L ± 0.34 of L-lactic acid, with a yield of 82.7%, being the first example of second-generation biomass valorised with this yeast strain, to the best of our knowledge. Remarkably, the fermentation performances were comparable with the ones obtained in the control medium. CONCLUSION: This study validates the exploitation of cotton post-industrial waste as a possible feedstock for the production of commodity chemicals in microbial cell-based biorefineries. The presented strategy demonstrates the possibility of implementing a circular bioeconomy approach in manufacturing textile industries.


Assuntos
Resíduos Industriais , Saccharomyces cerevisiae , Fermentação , Ácido Láctico , Hidrólise , Hidróxido de Sódio , Têxteis , Glucose
9.
Rapid Commun Mass Spectrom ; 38(5): e9705, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38343169

RESUMO

RATIONALE: The demand for weight loss products is increasing as slimness emerges as the new aesthetic standard and people's desire to achieve it increases. In addition, the distribution and sale of products containing illegal ingredients, pharmaceuticals, and chemicals for which safety is not guaranteed and that cannot be used as foods or dietary supplements are increasing. Thus, the development of an analytical method that could monitor these illegal products is required. METHODS: A high-performance liquid chromatography-photodiode array method capable of rapid and reliable qualitative and quantitative analyses of 43 weight loss agents was established and validated. RESULTS: The process involved dividing analytes into three groups for rapid analysis; when bisacodyl was mixed with chlorocyclopentylsibutramine, it decomposed into its metabolites: monoacetyl bisacodyl and bis-(p-hydroxypheny)-pyridyl-2-methane. This decomposition was due to NaOH that was used to prepare the chlorocyclopentylsibutramine standard solution. Bisacodyl did not degrade when mixed with neutralized chlorocyclopentylsibutramine, whereas when NaOH was added, it rapidly degraded. We identified the bisacodyl degradation products using liquid chromatography-quadrupole-Orbitrap/mass spectrometry. MS2 spectra with proposed structures of fragment peaks were also obtained. CONCLUSIONS: The developed method could be used to regulate slimming products that threaten public health, and knowledge of bisacodyl degradation will be used as the basis for developing an analytic method.


Assuntos
Fármacos Antiobesidade , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Fármacos Antiobesidade/análise , Bisacodil/análise , Hidróxido de Sódio , Suplementos Nutricionais/análise
10.
Environ Sci Technol ; 58(4): 2017-2026, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38214482

RESUMO

Understanding the dissolution of boehmite in highly alkaline solutions is important to processing complex nuclear waste stored at the Hanford (WA) and Savannah River (SC) sites in the United States. Here, we report the adsorption of model carboxylates on boehmite nanoplates in alkaline solutions and their effects on boehmite dissolution in 3 M NaOH at 80 °C. Although expectedly lower than at circumneutral pH, adsorption of oxalate occurred at pH 13, with adsorption decreasing linearly to 3 M NaOH. Classical molecular dynamics simulations suggest that the adsorption of oxalate dianions onto the boehmite surface under high pH can occur through either inner- or outer-sphere complexation mechanisms depending on adsorption sites. However, both adsorption models indicate relatively weak binding, with an energy preference of 1.26 to 2.10 kcal/mol. By preloading boehmite nanoplates with oxalate or acetate, we observed suppression of dissolution rates by 23 or 10%, respectively, compared to pure solids. Scanning electron microscopy and transmission electron microscopy characterizations revealed no detectable difference in the morphologic evolution of the dissolving boehmite materials. We conclude that preadsorbed carboxylates can persist on boehmite surfaces, decreasing the density of dissolution-active sites and thereby adding extrinsic controls on dissolution rates.


Assuntos
Hidróxido de Alumínio , Óxido de Alumínio , Hidróxido de Sódio , Hidróxido de Alumínio/química , Óxido de Alumínio/química , Adsorção , Oxalatos
11.
Nature ; 554(7691): 224-228, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29420466

RESUMO

Synthetic structural materials with exceptional mechanical performance suffer from either large weight and adverse environmental impact (for example, steels and alloys) or complex manufacturing processes and thus high cost (for example, polymer-based and biomimetic composites). Natural wood is a low-cost and abundant material and has been used for millennia as a structural material for building and furniture construction. However, the mechanical performance of natural wood (its strength and toughness) is unsatisfactory for many advanced engineering structures and applications. Pre-treatment with steam, heat, ammonia or cold rolling followed by densification has led to the enhanced mechanical performance of natural wood. However, the existing methods result in incomplete densification and lack dimensional stability, particularly in response to humid environments, and wood treated in these ways can expand and weaken. Here we report a simple and effective strategy to transform bulk natural wood directly into a high-performance structural material with a more than tenfold increase in strength, toughness and ballistic resistance and with greater dimensional stability. Our two-step process involves the partial removal of lignin and hemicellulose from the natural wood via a boiling process in an aqueous mixture of NaOH and Na2SO3 followed by hot-pressing, leading to the total collapse of cell walls and the complete densification of the natural wood with highly aligned cellulose nanofibres. This strategy is shown to be universally effective for various species of wood. Our processed wood has a specific strength higher than that of most structural metals and alloys, making it a low-cost, high-performance, lightweight alternative.


Assuntos
Madeira/química , Ligas/química , Parede Celular/química , Celulose/química , Temperatura Alta , Lignina/química , Lignina/isolamento & purificação , Metais/química , Peso Molecular , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Hidróxido de Sódio/química , Sulfitos/química , Resistência à Tração , Madeira/classificação
12.
Environ Res ; 247: 118180, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38220085

RESUMO

Recently, the integration of biochemical and thermochemical processes is recognized as a promising strategy for the valorization of lignocellulosic biomass into renewable energy production. In this study, different routes for the valorization of hemp hurd for biohydrogen and biomethane production were proposed, including anaerobic digestion (AD), hydrothermal carbonization, and steam gasification. AD results revealed that NaOH pre-treatment of hemp hurd improved biomethane production yield by 164%. Comparing hydrochars from raw hemp, digestate derived hydrochars had higher mass yield due to changes in composition during AD as well as high ash content of digestates. It was found that high ash content of digestates originated from inorganic compounds in inoculum that accumulated over hemp hurd during anaerobic digestion process. Among feedstocks (hydrochars and raw hemp hurd), hemp hurd derived hydrochar at 200 °C showed the best performance in terms of H2 yield (1278 mL/g) whereas carbon efficiency reached % 92 in case of digestate derived hydrochar at 200 °C. HTC improved the steam gasification performance of hemp hurd whereas hydrochars from NaOH pretreated digestate yielded lowest hydrogen production due to the high content of inorganics, particularly phosphorus (P) and aluminum (Al). According to BMP test, spent liquor obtained at the lowest HTC temperature (200 °C) exhibited the highest BMP, reaching 213 mL CH4/g COD. Considering the overall gas products of four different routes, it is concluded that HTC as a post-treatment exhibits slightly better performance than HTC as pre-treatment. Although alkali pretreatment enhanced the anaerobic digestion performance, the resulting hydrochars exhibited low gasification activity.


Assuntos
Biocombustíveis , Vapor , Anaerobiose , Temperatura , Hidróxido de Sódio , Carbono/química , Hidrogênio
13.
Environ Res ; 252(Pt 2): 118876, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582420

RESUMO

The rapid transition towards modernization and industrialization led to an increase in urban population, resulting in paramount challenge to municipal sewage sludge management. Anaerobic digestion (AD) serves as a promising venue for energy recovery from waste-activated sludge (WAS). Addressing the challenge of breaking down floc structures and microbial cells is crucial for releasing extracellular polymeric substances and cytoplasmic macromolecules to facilitate hydrolysis and fermentation process. The present study aims to introduce a combined process of alkaline/acid pre-treatments and AD to enhance sludge digestion and biogas production. The study investigates the influence of alkali pretreatment at ambient temperature using four alkali reagents (NaOH, Ca(OH)2, Mg(OH)2, and KOH). The primary goal is to provide insights into the intricate interplay of alkali dosages (0.04-0.12 g/gTS) on key physic-chemical parameters crucial for optimizing the pre-treatment dosage. Under the optimized alkaline/acid pre-treatment condition, the TSS reduction of 18%-30% was achieved. An increase in sCOD concentration (24%-50%) signifies the enhanced hydrolysis and solubilization rate of organic substrate in WAS. Finally, the biomethane potential test (BMPT) was performed for pre-treated WAS samples. The maximum methane (CH4) yield was observed in combination A1 (244 mL/g) and D1 (253 mL/g), demonstrating the pivotal role of alkali optimization in enhancing AD efficiency. This study serves as a valuable resource to policymakers, researchers, and technocrats in addressing challenges associated to sludge management.


Assuntos
Biocombustíveis , Esgotos , Esgotos/química , Biocombustíveis/análise , Anaerobiose , Eliminação de Resíduos Líquidos/métodos , Álcalis/química , Metano , Hidróxido de Sódio/química , Hidróxido de Cálcio/química , Hidróxido de Magnésio/química , Reatores Biológicos , Hidróxidos/química , Compostos de Potássio/química
14.
Int J Phytoremediation ; 26(5): 626-638, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37735932

RESUMO

Textile industries use large amounts of water as well as dyes. These dyes containing water are then discharged into the water bodies causing a significant role in water pollution. Brilliant Green dye contributes to many harmful diseases related to the respiratory and gastrointestinal tract. In this study, Symplocos racemosa (SR) agro-waste was chemically treated with acid (SR-HCl) and base (SR-NaOH) and then used for removing Brilliant Green Dye (BGD) on the batch scale. They were characterized by SEM, EDX, FTIR, XRD, TGA and DSC. Optimized conditions were 30 °C temperature, pH 6, adsorbent dose of 0.10 g/25 ml dye solution, shaking speed of 100 revolutions per minute, initial dye concentration of 50 ppm and 35 min time for shaking adsorbent and dye solution. Adsorption data obtained were analyzed using isotherms. The experimental data was found to fit well with the Langmuir model and the maximum adsorption capacity (qmax) of BGD on the SR, SR-HCl, and SR-NaOH was revealed to be 62.90, 65.40, and 71 mg/g respectively. Kinetic data (pseudo-first-order and pseudo-second-order) were evaluated and adsorption tends to follow the pseudo-2nd-order, which indicated the chemisorption mechanism. The results revealed that Symplocos racemosa agro-waste can be considered as the potential biosorbent.


Assuntos
Corantes , Compostos de Amônio Quaternário , Poluentes Químicos da Água , Corantes/química , Biodegradação Ambiental , Mutagênicos , Adsorção , Hidróxido de Sódio , Água , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Termodinâmica
15.
Pediatr Surg Int ; 40(1): 118, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698156

RESUMO

PURPOSE: We aimed to examine the effectiveness of mother milk exosomes in treating corrosive esophageal burns. MATERIALS AND METHODS: 32 rats were separated into four equal groups and weighed individually before the procedure. A corrosive esophageal burn model was created with 12.5% sodium hydroxide by a 3F Fogarty catheter. Group 1 did not apply any process or treatment, Group 2 was burned, and no treatment was performed. Group 3 was burned, and then 0.5 cc/day of mother milk exosome extract was given. Group 4 was not applied any process, and 0.5 cc/day mother milk exosome extract was given. All rats were weighed again and sacrificed. Biopsy samples were sent to the pathology laboratory for histopathological examination (in terms of inflammation, fibrosis, and necrosis).Kindly check and confrm all email ids.The e-mail addresses and affiliation of all authors were checked. Affiliation departments are as stated on the title page. There is no change. RESULTS: A significant difference was found in the results of inflammation and fibrosis. There was a meaningful difference in fibrosis between the 2nd and 3rd groups. There was weight gain in groups 1, 3 and 4. Statistical evaluations for each group were significant. CONCLUSION: It was observed that breast milk exosomes may be effective in inflammation and fibrosis formation in treating corrosive esophageal burns. This suggested that breast milk exosomes reduce stricture formation due to esophageal corrosion.Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author 1 Given name: [specify authors given name] Last name [specify authors last name]. Also, kindly confirm the details in the metadata are correct.The names and affiliation of all authors were checked. Affiliation departments are as stated on the title page. There is no change. Also we confirm the details in the metadata.


Assuntos
Queimaduras Químicas , Modelos Animais de Doenças , Exossomos , Animais , Ratos , Queimaduras Químicas/terapia , Esofagite/induzido quimicamente , Esofagite/patologia , Cáusticos/toxicidade , Leite Humano , Feminino , Hidróxido de Sódio/toxicidade , Esôfago/patologia , Masculino
16.
Int J Mol Sci ; 25(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38339046

RESUMO

We designed and characterized chitosan-caseinate fibers processed through wet spinning for biomedical applications such as drug delivery from knitted medical devices. Sodium caseinate was either incorporated directly into the chitosan dope or allowed to diffuse into the chitosan hydrogel from a coagulation bath containing sodium caseinate and sodium hydroxide (NaOH). The latter route, where caseinate was incorporated in the neutralization bath, produced fibers with better mechanical properties for textile applications than those formed by the chitosan-caseinate mixed collodion route. The latter processing method consists of enriching a pre-formed chitosan hydrogel with caseinate, preserving the structure of the semicrystalline hydrogel without drastically affecting interactions involved in the chitosan self-assembly. Thus, dried fibers, after coagulation in a NaOH/sodium caseinate aqueous bath, exhibited preserved ultimate mechanical properties. The crystallinity ratio of chitosan was not significantly impacted by the presence of caseinate. However, when caseinate was incorporated into the chitosan dope, chitosan-caseinate fibers exhibited lower ultimate mechanical properties, possibly due to a lower entanglement density in the amorphous phase of the chitosan matrix. A standpoint is to optimize the chitosan-caseinate composition ratio and processing route to find a good compromise between the preservation of fiber mechanical properties and appropriate fiber composition for potential application in drug release.


Assuntos
Quitosana , Quitosana/química , Caseínas , Hidróxido de Sódio , Água/química , Hidrogéis
17.
J Environ Manage ; 357: 120786, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38583386

RESUMO

An innovative task was undertaken to convert ubiquitous and toxic electronic waste, waste toner powder (WTP), into novel adsorbents. Alkaline modification with KOH, NaOH, and NH4OH was employed for the first time to synthesize a series of surface-modified WTP with enhanced dispersibility and adsorption capacity. XRD, XRF, FTIR, and BET analyses confirmed that the prepared KOH-WTP, NaOH-WTP, and NH4OH-WTP were oxygen-functionalized self-doped iron oxide-graphite nanocomposites. The prepared adsorbents were used to remove methylene blue and tetracycline from aqueous solutions. KOH-WTP (0.1 g/100 mL) adsorbed 80% of 10 mg/L methylene blue within 1 h, while 0.1 g/100 mL NH4OH-WTP removed 72% of 10 mg/L tetracycline in 3 h. Exploring surface chemistry by altering solution pH and temperature suggested that hydrogen bonding, electrostatic interactions, π-π electron stacking, and pore filling were plausible adsorption mechanisms. Scanning electron microscopy revealed a diminishing adsorbents porosity after adsorption proving the filling of pores by the adsorbates. KOH-WTP and NH4OH-WTP removed 77% and 61% of methylene blue and tetracycline respectively in the fourth reuse. The adsorption data of methylene blue and tetracycline fitted the Freundlich isotherm model. The maximum adsorption capacities of KOH-WTP and NH4OH-WTP for methylene blue and tetracycline were 59 mg/g and 43 mg/g respectively. The prepared adsorbents were also compared with other adsorbents to assess their performance. The transformation of waste toner powder into magnetically separable oxygen-functionalized WTP with outstanding recyclability and adsorption capacity showcases a significant advancement in sustainable wastewater treatment. This further aligns with the principles of the circular economy through the utilization of toxic e-waste in value-added applications. Additionally, magnetic separation of surface-modified WTP post-treatment can curtail filtration and centrifugation expenses and adsorbent loss during wastewater treatment.


Assuntos
Compostos Férricos , Grafite , Nanocompostos , Poluentes Químicos da Água , Azul de Metileno , Adsorção , Pós , Hidróxido de Sódio , Tetraciclina , Antibacterianos , Oxigênio , Poluentes Químicos da Água/análise , Cinética , Concentração de Íons de Hidrogênio
18.
Water Sci Technol ; 89(10): 2812-2822, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38822616

RESUMO

The sequential extraction routes of biogenic materials from sewage sludge (SS) were investigated. Physical methods (ultrasound, heating) and chemical methods (sodium hydroxide, sodium carbonate) were used to extract extracellular polymeric substances (EPS) and alginate-like extracellular polymers (ALEs) from SS. The residues after extraction were further subjected to physical methods (heating) and chemical methods (sulfuric acid, sodium hydroxide) for protein extraction. A comparison was made between sequential extraction routes and direct extraction of biomaterials from sludge in terms of extraction quantity, material properties, and applicability. The results showed that sequential extraction of biomaterials is feasible. The highest extraction quantities were obtained when using sodium carbonate for EPS and ALE extraction and sodium hydroxide for protein, reaching 449.80 mg/gVSS, 109.78 mg/gVSS, and 5447.08 mg/L, respectively. Sequential extraction procedures facilitate the extraction of biomaterials. Finally, suitable extraction methods for different application scenarios were analyzed.


Assuntos
Esgotos , Esgotos/química , Hidróxido de Sódio/química , Fracionamento Químico/métodos , Carbonatos/química , Estudos de Viabilidade
19.
Pharm Dev Technol ; 29(4): 339-352, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38502579

RESUMO

We recently reported the potential of a new gallium compound, gallium acetylacetonate (GaAcAc) in combating osteoclastic bone resorption through inhibition of osteoclast differentiation and function. Herein, we focused on 3D-printed polylactic acid scaffolds that were loaded with GaAcAc and investigated the impact of scaffold pretreatment with polydopamine (PDA) or sodium hydroxide (NaOH). We observed a remarkable increase in scaffold hydrophilicity with PDA or NaOH pretreatment while biocompatibility and in vitro degradation were not affected. NaOH-pretreated scaffolds showed the highest amount of GaAcAc loading when compared to other scaffolds (p < 0.05). NaOH-pretreated scaffolds with GaAcAc loading showed effective reduction of osteoclast counts and size. The trend was supported by suppression of key osteoclast differentiation markers such as NFAT2, c-Fos, TRAF6, & TRAP. All GaAcAc-loaded scaffolds, regardless of surface pretreatment, were effective in inhibiting osteoclast function as evidenced by reduction in the number of resorptive pits in bovine cortical bone slices (p < 0.01). The suppression of osteoclast function according to the type of scaffold followed the ranking: GaAcAc loading without surface pretreatment > GaAcAc loading with NaOH pretreatment > GaAcAc loading with PDA pretreatment. Additional studies will be needed to fully elucidate the impact of surface pretreatment on the efficacy and safety of GaAcAc-loaded 3D-printed scaffolds.


Assuntos
Reabsorção Óssea , Osteoclastos , Impressão Tridimensional , Alicerces Teciduais , Animais , Osteoclastos/efeitos dos fármacos , Alicerces Teciduais/química , Reabsorção Óssea/tratamento farmacológico , Bovinos , Camundongos , Poliésteres/química , Gálio/química , Gálio/farmacologia , Pentanonas/química , Pentanonas/administração & dosagem , Pentanonas/farmacologia , Hidróxido de Sódio , Diferenciação Celular/efeitos dos fármacos
20.
Environ Geochem Health ; 46(6): 182, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695980

RESUMO

Due to the development of industries such as mining, smelting, industrial electroplating, tanning, and mechanical manufacturing, heavy metals were discharged into water bodies seriously affecting water quality. Bamboo charcoal, as an environmentally friendly new adsorbent material, in this paper, the virgin bamboo charcoal (denoted as WBC) was modified with different concentrations of KMnO4 and NaOH to obtain KMnO4-modified bamboo charcoal (KBC) and NaOH-modified bamboo charcoal (NBC) which was used to disposed of water bodies containing Cu2+ and Zn2+. The main conclusions were as following: The adsorption of Cu2+ by WBC, KBC and NBC was significantly affected by pH value, and the optimum pH was 5.0. Differently, the acidity and alkalinity of the solution doesn't effect the adsorption of Zn2+ seriousely. Meanwhile, surface diffusion and pore diffusion jointly determine the adsorption rate of Cu2+ and Zn2+. The test result of EDS showed that Mn-O groups formed on the surface of K6 (WBC treated by 0.06 mol/L KMnO4) can promote the adsorption of Cu2+ and Zn2+ at a great degree. The O content on N6(WBC treated by 6 mol/L NaOH) surface increased by 30.95% compared with WBC. It is speculated that the increase of carbonyl group on the surface of NBC is one of the reasons for the improvement of Cu2+ and Zn2+ adsorption capacity. Finally, the residual concentrations of Cu2+ and Zn2+ in wastewater are much lower than 0.5 mg/L and 1.0 mg/L, respectively. Thus it can be seen, KBC and NBC could be a promising adsorbent for heavy metals.


Assuntos
Carvão Vegetal , Cobre , Poluentes Químicos da Água , Zinco , Adsorção , Zinco/química , Cobre/química , Carvão Vegetal/química , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Permanganato de Potássio/química , Purificação da Água/métodos , Sasa/química , Hidróxido de Sódio/química
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