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In a contemporary sustainable economy, innovation is a prerequisite to recycling waste into new efficient materials designed to minimize pollution and conserve non-renewable natural resources. Using an innovative approach to remediating metal-polluted water, in this study, eggshell waste was used to prepare two new low-cost nanoadsorbents for the retrieval of nickel from aqueous solutions. Scanning electron microscopy (SEM) results show that in the first eggshell-zeolite (EZ) adsorbent, the zeolite nanoparticles were loaded in the eggshell pores. The preparation for the second (iron(III) oxide-hydroxide)-eggshell-zeolite (FEZ) nanoadsorbent led to double functionalization of the eggshell base with the zeolite nanoparticles, upon simultaneous loading of the pores of the eggshell and zeolite surface with FeOOH particles. Structural modification of the eggshell led to a significant increase in the specific surface, as confirmed using BET analysis. These features enabled the composite EZ and FEZ to remove nickel from aqueous solutions with high performance and adsorption capacities of 321.1 mg/g and 287.9 mg/g, respectively. The results indicate that nickel adsorption on EZ and FEZ is a multimolecular layer, spontaneous, and endothermic process. Concomitantly, the desorption results reflect the high reusability of these two nanomaterials, collectively suggesting the use of waste in the design of new, low-cost, and highly efficient composite nanoadsorbents for environmental bioremediation.
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Viscum is one of the most famous and appreciated medicinal plants in Europe and beyond. The symbiotic relationship with the host tree and various endogenous and ecological aspects are the main factors on which the viscum metabolites' profiles depend. In addition, European traditional medicine mentions that only in two periods of the year (summer solstice and winter solstice) the therapeutic potential of the plant is at its maximum. Many studies have investigated the phytotherapeutic properties of viscum grown on different species of trees. However, studies on Romanian viscum are relatively few and refer mainly to the antioxidant and antiproliferative activity of mistletoe grown on Acer campestre, Fraxinus excelsior, Populus nigra, Malus domestica, or Robinia pseudoacacia. This study reports the first complete low-molecular-weight metabolite profile of Romanian wild-grown European viscum. A total of 140 metabolites were identified under mass spectra (MS) positive mode from 15 secondary metabolite categories: flavonoids, amino acids and peptides, terpenoids, phenolic acids, fatty acids, organic acids, nucleosides, alcohols and esters, amines, coumarins, alkaloids, lignans, steroids, aldehydes, and miscellaneous. In addition, the biological activity of each class of metabolite is discussed. The development of a simple and selective phyto-engineered AuNPs carrier assembly is reported and an evaluation of the nanocarrier system's morpho-structure is performed, to capitalize on the beneficial properties of viscum and AuNPs.
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Sustainable waste and water management are key components of the newest EU policy regarding the circular economy. Simple, performant and inexpensive water treatment methods based on reusing waste are prerequisites for human health, sustainable development and environmental remediation. The design of performant, cost-effective absorbents represents a topical issue in wastewater treatment. This study aimed to investigate the development of a newly engineered adsorbent by functionalizing two different types of waste (industrial and food) with magnetic nanoparticles as environmentally friendly, highly efficient, cheap material for cadmium removal from aqueous solutions. This nano-engineered adsorbent (EFM) derived from waste eggshell and fly ash was used to remove the cadmium from the aqueous solution. SEM analysis has demonstrated that magnetite nanoparticles were successfully loaded with each waste. In addition, was obtained a double functionalization of the eggshell particles with ash and magnetite particles. As a result of this, the EFM surface area substantially increased, as confirmed by BET. A comprehensive characterization (BET, FT-IR, SEM, XRD and TGA) was performed to study the properties of this newly engineered adsorbent. Batch experiments were conducted to investigate the influence of different reaction parameters: temperature, pH, contact time, dosage adsorbent, initial concentration. Results showed that cadmium adsorption reached equilibrium in 120 min., at pH 6.5, for 0.25 g of adsorbent. The maximum efficiency was 99.9%. The adsorption isotherms research displayed that the Cd2+ adsorption fitted on the Freundlich model indicated a multi-molecular layer adsorption process. In addition, the thermodynamic study (ΔG < 0, ΔH > 0; ΔS > 0) shows that cadmium adsorption is a spontaneous and endothermic process. The adsorbent kinetic study was described with the pseudo-second-order model indicating a chemisorption mechanism. Desorption results showed that the nano-engineered adsorbent (EFM) can be reused. These data confirmed the possibility to enrich relevant theoretical knowledge in the field of waste recovery for obtaining newly designed adsorbents, performant and inexpensive for wastewater remediation.
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Cádmio , Poluentes Químicos da Água , Adsorção , Animais , Cádmio/química , Cinza de Carvão , Casca de Ovo , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Águas Residuárias/química , Poluentes Químicos da Água/químicaRESUMO
The paper aims to study the impact of ozone (O3) treatment on the microstructural changes of the tooth enamel after the treatment at different time intervals. The ozonation was performed with gaseous O3 produced by HealOzone X4, the demineralization level was measured with the DiagnoDent Pen 2190 device, and the microstructure changes of enamel surface were observed using scanning electron microscopy (SEM) analysis. The results showed the exposure to O3 for 40-50 seconds enhanced enamel micro-hardness and ensures a rate of remineralization between 96.82-97.38%. In conclusion, in search of new minimally invasive solutions in the treatment of caries and to offer antimicrobial support of the oral cavity, the use of O3 as an alternative therapy to classical solutions may be a viable solution in dentistry.
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Ozônio , Desmineralização do Dente , Humanos , Ozônio/farmacologia , Remineralização Dentária/métodos , Dureza , Microscopia Eletrônica de Varredura , Esmalte DentárioRESUMO
BACKGROUND: In orthodontic therapy, the enamel around brackets is very susceptible to bacterial-plaque retention, which represents a risk factor for dental tissues. The aim of this study was to evaluate the effect of methylene blue and a chlorophyllin-phycocyanin mixture, used with and without light activation, in contrast with a 2% chlorhexidine solution, on Streptococcus mutans colonies. METHODS: Twenty caries-free human extracted teeth were randomized into five groups. A Streptococcus mutans suspension was inoculated on teeth in groups B, C, D, and E (A was the positive-control group). Bacterial colonies from groups C, D, and E (B was the negative-control group) were subjected to photosensitizers and 2% chlorhexidine solution. For groups C and D, a combined therapy consisting of photosensitizer and light activation was performed. The Streptococcus mutans colonies were counted, and smears were examined with an optical microscope. Two methods of statistical analysis, unidirectional analysis of variance and the Tukey-Kramer test, were used to evaluate the results. RESULTS: A statistically significant reduction in bacterial colonies was detected after the combined therapy was applied for groups C and D, but the most marked bacterial reduction was observed for group D, where a laser-activated chlorophyll-phycocyanin mixture was used. CONCLUSIONS: Photodynamic therapy in combination with methylene blue or chlorophyllin-phycocyanin mixture sensitizers induces a statistically significant decrease in the number of bacterial colonies.
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Anti-Infecciosos , Fotoquimioterapia , Descontaminação , Humanos , Fármacos Fotossensibilizantes , Streptococcus mutansRESUMO
The metabolites profile of a plant is greatly influenced by geographical factors and the ecological environment. Various studies focused on artemisinin and its derivates for their antiparasitic and antitumoral effects. However, after the isolation and purification stage, their pharmaceutical potential is limited due to their low bioavailability, permeability and lifetime. The antibacterial activity of essential oils has been another topic of interest for many studies on this plant. Nevertheless, only a few studies investigate other metabolites in Artemisia annua. Considering that secondary metabolites act synergistically in a plant, the existence of other metabolites with antitumor and high immunomodulating activity is even more important. Novel nano-carrier systems obtained by loading herbs into magnetic nanoparticles ensures the increase in the antitumor effect, but also, overcoming the barriers related to permeability, localization. This study reported the first complete metabolic profile from wild grown Romanian Artemisia annua. A total of 103 metabolites were identified under mass spectra (MS) positive mode from 13 secondary metabolite categories: amino acids, terpenoids, steroids, coumarins, flavonoids, organic acids, fatty acids, phenolic acids, carbohydrates, glycosides, aldehydes, hydrocarbons, etc. In addition, the biological activity of each class of metabolites was discussed. We further developed a simple and inexpensive nano-carrier system with the intention to capitalize on the beneficial properties of both components. Evaluation of the nano-carrier system's morpho-structural and magnetic properties was performed.
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BACKGROUND: Hospitalization for acute decompensated heart failure (ADHF) remains a major source of morbidity and mortality. The current study aimed to investigate the feasibility, safety, and efficacy of outpatient furosemide intravenous (IV) infusion following hospitalization for ADHF. METHODS: In a single center, prospective, randomized, double-blind study, 100 patients were randomized to receive standard of care (Group 1), IV placebo infusion (Group 2), or IV furosemide infusion (Group 3) over 3h, biweekly for a one-month period following ADHF hospitalization. Patients in Groups 2/3 also received a comprehensive HF-care protocol including bi-weekly clinic visits for dose-adjusted IV-diuretics, medication adjustment and education. Echocardiography, quality of life and depression questionnaires were performed at baseline and 30-day follow-up. The primary outcome was 30-day re-hospitalization for ADHF. RESULTS: Overall, a total of 94 patients were included in the study (mean age 64 years, 56% males, 69% African American). There were a total of 14 (15%) hospitalizations for ADHF at 30 days, 6 (17.1%) in Group 1, 7 (22.6%) in Group 2, and 1 (3.7%) in Group 3 (overall p = 0.11; p = 0.037 comparing Groups 2 and 3). Patients receiving IV furosemide infusion experienced significantly greater urine output and weight loss compared to those receiving placebo without any significant increase creatinine and no significant between group differences in echocardiography parameters, KCCQ or depression scores. CONCLUSION: The use of a standardized protocol of outpatient IV furosemide infusion for a one-month period following hospitalization for ADHF was found to be safe and efficacious in reducing 30-day re-hospitalization.
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Diuréticos/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Hospitalização/estatística & dados numéricos , Pacientes Ambulatoriais/estatística & dados numéricos , Qualidade de Vida , Idoso , Método Duplo-Cego , Feminino , Insuficiência Cardíaca/patologia , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Inibidores de Simportadores de Cloreto de Sódio e Potássio , Resultado do TratamentoRESUMO
The goal of the study was to evaluate the influence of the solvent properties on the crystal characteristics of ß-cyclodextrin (ß-CD) recrystallized from alcohol-water solvent mixtures, with possible applications for the preparation, purifying and complexation of ß-CD. For the first time, structure-property relationships (QSPRs) between the hydrophobicity of alcohols or dielectric constant of solvents used for recrystallization of ß-CD and its properties (such as crystallinity index, CI) have been obtained. Recrystallized ß-CD from water and C1-C4 alcohol-water solutions provide ß-CD with higher CI values of 99.4(±5.9)% for ethanol-water (1:4, v/v) as recrystallizing system. This property has a parabolic variation with the logP (octanol/water partition coefficient) of the alcohol (r2â¯=â¯0.998). Solvent parameters also influence the ß-CD crystal characteristics, as was demonstrated by X-ray diffractometry refinement, infrared spectroscopy and thermal analyses.
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Solventes/química , beta-Ciclodextrinas/química , Varredura Diferencial de Calorimetria/métodos , Cristalização/métodos , Etanol/química , Interações Hidrofóbicas e Hidrofílicas , Solubilidade , Espectrofotometria Infravermelho/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Termogravimetria/métodos , Água/química , Difração de Raios X/métodosRESUMO
ß-Cyclodextrin- and 2-hydroxypropyl-ß-cyclodextrin/Danube common nase (Chondrostoma nasus L.) oil complexes (ß-CD- and HP-ß-CD/CNO) have been obtained for the first time. The fatty acid (FA) profile of the CNO indicates an important content of polyunsaturated fatty acids, the most important being eicosapentaenoic acid (EPA, 6.3%) and docosahexaenoic acid (DHA, 1.6%), both ω-3 FAs. The complexes have been obtained by kneading method. The moisture content and successful of molecular encapsulation have been evaluated by thermal and spectroscopic techniques. Thermogravimetry and differential scanning calorimetry analyses reveals that the moisture content of CD/CNO complexes significantly decreased, compared to starting CDs. On the other hand, the crystallinity index was for the first time determined for such type of complexes, the ß-CD/CNO complex having values of 43.9(±18.3)%, according to X-ray diffractometry. FA profile and CD/CNO characteristics sustain the use of these ω-3 based complexes for food supplements or functional food products, but further studies are needed.
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2-Hidroxipropil-beta-Ciclodextrina/química , Óleos de Peixe/química , beta-Ciclodextrinas/química , Animais , Varredura Diferencial de Calorimetria , Cyprinidae , Solubilidade , Difração de Raios XRESUMO
The goal of the present study was the evaluation of the fatty acid (FA) profile of lipid fraction from dry common beans (Phaseolus vulgaris L.) (CBO) harvested from North-East (NE) and South-West (SW) of Romania and to protect against thermal and oxidative degradation of the contained omega-3 and omega-6 polyunsaturated fatty acid (PUFA) glycerides by ß-cyclodextrin (ß-CD) nanoencapsulation, using kneading method. The most abundant FAs in the CBO samples were PUFAs, according to gas chromatography-mass spectrometry (GC-MS) analysis. Linoleic acid (methyl ester) was the main constituent, having relative concentrations of 43.4 (±1.95) % and 35.23 (±0.68) % for the lipid fractions separated from the common beans harvested from the NE and SW of Romania, respectively. Higher relative concentrations were obtained for the omega-3 α-linolenic acid methyl ester at values of 13.13 (±0.59) % and 15.72 (±0.30) % for NE and SW Romanian samples, respectively. The omega-3/omega-6 ratio consistently exceeds the lower limit value of 0.2, from where the PUFA glyceride mixture is valuable for the human health. This value was 0.32 (±0.02) for the NE samples and significantly higher for the CBO-SW samples, 0.51 (±0.01). These highly hydrophobic mixtures especially consisting of PUFA triglycerides provide ß-CD complexes having higher thermal and oxidative stability. Kneading method allowed obtaining ß-CD/CBO powder-like complexes with higher recovery yields of >70%. Thermal analyses of complexes revealed a lower content of hydration water (3.3-5.8% up to 110°C in thermogravimetry (TG) analysis and 154-347 J/g endothermal effect in differential scanning calorimetry (DSC) analysis) in comparison with the ß-CD hydrate (12.1% and 479.5-480 J/g, respectively). These findings support the molecular inclusion process of FA moieties into the ß-CD cavity. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) analysis reveals the formation of the ß-CD/CBO inclusion complexes by restricting the vibration and bending of some bonds from the host and guest molecules. Moreover, powder X-ray diffractometry (PXRD) analysis confirm the formation of the host-guest complexes by modifying the diffractograms for ß-CD/CBO complexes in comparison with the ß-CD and ß-CD + CBO physical mixtures. A significant reduction of the level of crystallinity from 93.3 (±5.3) % for ß-CD to 60-60.9% for the corresponding ß-CD/CBO complexes have been determined. The encapsulation efficiency (EE), the profile of FAs, as well as the controlled release of the encapsulated oil have also been evaluated. The EE was >40% in all cases, the highest value being obtained for ß-CD/CBO-SW complex. The SFA content increased, while the unsaturated FA glycerides had lower relative concentrations in the encapsulated CBO samples. It can be emphasized that the main omega-3 FA (namely α-linolenic acid glycerides) had close concentrations in the encapsulated and raw CBOs (13.13 (±0.59) % and 14.04 (±1.54) % for non-encapsulated and encapsulated CBO-NE samples, 15.72 (±0.30) % and 12.41 (±1.95) % for the corresponding CBO-SW samples, respectively). The overall unsaturated FA content significantly decreased after complexation (from 19.03-19.16% for the raw CBOs to 17.3-17.7% for encapsulated oils in the case of MUFAs, and from 55.7-58.8% to 35.13-43.36% for PUFAs). On the other hand, the omega-3/omega-6 ratio increased by ß-CD nanoencapsulation to 0.51 (±0.07) and 0.76 (0.26) for ß-CD/CBO-NE and ß-CD/CBO-SW complexes, respectively. As a conclusion, the lipid fractions of the Romanian common beans are good candidates for ß-CD complexation and they can be protected against thermal and oxidative degradation in common beans based food products such as functional foods or food supplements using natural CDs.
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Ácidos Graxos/metabolismo , Phaseolus/metabolismo , Óleos de Plantas/química , beta-Ciclodextrinas/química , Ácidos Graxos/análise , Ácidos Graxos Ômega-3/química , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-6/química , Ácidos Graxos Ômega-6/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Ácido Linoleico/análise , Ácido Linoleico/metabolismo , Romênia , Espectroscopia de Infravermelho com Transformada de Fourier , TermogravimetriaRESUMO
The aim of this paper was to produce a new composite material based on carbon and iron oxides, starting from soluble starch and ferric chloride. The composite material was synthesized by simple thermal decomposition of a reaction mass obtained from starch and iron chloride, in an inert atmosphere. Starch used as a carbon source also efficiently stabilizes the iron oxides particles obtained during the thermal decomposition. The reaction mass used for the thermal decomposition was obtained by simultaneously mixing the carbon and iron oxide precursors, without addition of any precipitation agent. The proper composite material can be obtained by rigorously adhering to the stirring time, temperature, and water quantity used during the preparation of the reaction mass, as well as the thermal regime and the controlled atmosphere used during the thermal decomposition. Synthesized materials were characterized using thermogravimetric analysis, X-Ray Diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infra-red spectroscopy (FT-IR). The performances of the obtained material were highlighted by studying their adsorbent properties and by determining the maximum adsorption capacity for arsenic removal from aqueous solutions.
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Carbono/química , Compostos Férricos/química , Amilopectina/química , Amilose/química , Arsênio/química , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios XRESUMO
Manganese ferrite nanopowder was prepared by thermal decomposition at 400°C of the gel synthesized from manganese and iron nitrates and polyvinyl alcohol. X-ray diffractometry evidenced that manganese ferrite was formed as single crystalline phase at this temperature. Scanning electron microscope images evidenced the formation of very fine spherical particles (d<11nm) of manganese ferrite, with specific surface area of 147m2/g. The powder obtained at 400°C was used as a catalyst for the oxidative degradation of phenol in aqueous solutions, in the presence of potassium peroxydisulfate as oxidant. High phenol removal efficiencies above 90% were reached at: pH 3-3.5, phenol initial concentration around 50mg/L, peroxydisulfate:phenol mass ratio 10:1, and catalyst dose 3g/L. Total organic carbon measurements showed that the degradation of phenol goes, under these conditions, to mineralization in an extent of 60%.
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Compostos Férricos/química , Compostos de Manganês/química , Nanopartículas/química , Fenol/química , Poluentes Químicos da Água/química , Catálise , Oxirredução , Sulfatos/química , Purificação da Água/métodosRESUMO
BACKGROUND Allgrove syndrome, or triple "A" syndrome (3A syndrome), is a rare autosomal recessive syndrome with variable phenotype, and an estimated prevalence of 1 per 1,000,000 individuals. Patients usually display the triad of achalasia, alacrima, and adrenocorticotropin (ACTH) insensitive adrenal insufficiency, though the presentation is inconsistent. CASE REPORT Here, the authors report a case of Allgrove syndrome in a pediatric patient with delayed diagnosis in order to raise awareness of this potentially fatal disease as a differential diagnosis of alacrima. CONCLUSIONS The prevalence of Allgrove syndrome may be much higher as a result of underdiagnosis and missed diagnosis due to the variable presentation and sudden unexplained childhood death from adrenal crisis. The authors review the characteristic symptoms of Allgrove syndrome in relation to the case study in order to avoid missed or delayed diagnosis, potentially decreasing morbidity, and mortality in those affected by this disease.
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Insuficiência Adrenal/diagnóstico , Acalasia Esofágica/diagnóstico , Oftalmopatias Hereditárias/diagnóstico , Doenças do Aparelho Lacrimal/diagnóstico , Criança , Diagnóstico Tardio , Feminino , HumanosRESUMO
The acidity constants Ka1 and Ka2 of 2-(5-mercapto-1,3,4-thiadiazol-2-ylthio)acetic acid have been determined both by experimental and theoretical methods. pKa computations at B3LYP/6-311+G(d,p) level of theory were carried out for the two tautomeric forms, thiol and thione, of the above-mentioned acid. Comparisons between the experimental and theoretical values led to the establishing of the most stable tautomer of 2-(5-mercapto-1,3,4-thiadiazol-2-ylthio)acetic acid in aqueous solution. Also, a DFT study regarding the reactivity, aromaticity and population analysis of the two tautomers has been performed.