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Medicinas Complementares
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1.
J Environ Manage ; 356: 120594, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503229

RESUMO

Almost all iron ore tailings (IOTs) required activation prior to use as SCMs, which limited their application in building materials. This study investigated HMPT-IOTs and discovered that they possess latent hydraulic and pozzolanic properties. In order to better utilize as SCM, mechanical properties, hydration reactions, hydration products, microstructure, and pores were comprehensively studied through mechanical tests, hydration heat tests, XRD, SEM, TG, and MIP. The results show that when HMPT-IOTs replace cement at 10 wt%, 20 wt% and 30 wt%, the compressive strength at 28 days is 41.9 MPa, 47.9 MPa and 37.5 MPa, respectively. When the substitution amount reaches 30 wt%, it will reduce the cumulative heat of hydration and promote early hydration reactions. The main hydration products are ettringite and Ca(OH)2. As the nucleation site of C-S-H, hydration products are interconnected, making the microstructure denser. At this substitution level, Ca(OH)2 consumption was about 2% at 28 days of age. Simultaneously, the total pore volume was only 0.01 mL/g greater than that of the control group, and the number of micropores and transition pores decreased by approximately 3%.


Assuntos
Materiais de Construção , Hidrogênio , Força Compressiva , Minerais , Ferro
2.
Int J Mol Sci ; 25(6)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38542093

RESUMO

Previous theoretical investigations of the reactions between an OH radical and a nucleobase have stated the most important pathways to be the C5-C6 addition for pyrimidines and the C8 addition for purines. Furthermore, the abstraction of a methyl hydrogen from thymine has also been proven an important pathway. The conclusions were based solely on gas-phase calculations and harmonic vibrational frequencies. In this paper, we supplement the calculations by applying solvent corrections through the polarizable continuum model (PCM) solvent model and applying anharmonicity in order to determine the importance of anharmonicity and solvent effects. Density functional theory (DFT) at the ωB97-D/6-311++G(2df,2pd) level with the Eckart tunneling correction is used. The total reaction rate constants are found to be 1.48 ×10-13 cm3 molecules-1s-1 for adenine, 1.02 ×10-11 cm3 molecules-1s-1 for guanine, 5.52 ×10-13 cm3 molecules-1s-1 for thymine, 1.47 ×10-13 cm3 molecules-1s-1 for cytosine and 7.59 ×10-14 cm3 molecules-1s-1 for uracil. These rates are found to be approximately two orders of magnitude larger than experimental values. We find that the tendencies observed for preferred pathways for reactions calculated in a solvent are comparable to the preferred pathways for reactions calculated in gas phase. We conclude that applying a solvent has a larger impact on more parameters compared to the inclusion of anharmonicity. For some reactions the inclusion of anharmonicity has no effect, whereas for others it does impact the energetics.


Assuntos
Timina , Uracila , Solventes , Adenina , Hidrogênio
3.
J Chromatogr A ; 1720: 464773, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38432106

RESUMO

Although the co-occurrences of isomeric chalcones and dihydroflavones widely appear in medicinal plants, the differentiation of such isomerism seldom succeeds using MS/MS, attributing to totally identical MS/MS spectra. Here, efforts were paid to pursue an eligible tool allowing to address the technical challenge. Being inspired by that one more proton signal is observed in 1H NMR spectrum of isoliquiritigenin than liquiritigenin when employing DMSO­d6 as solvent, hydrogen-deuterium exchange (HDX)-MS/MS was evaluated towards differentiating isomeric chalcones and dihydroflavones through replacing H2O with D2O to prepare the mobile phase. As a result, differences were observed for either MS1 or MS2 spectrum when comparing two pairs of isomers, such as liquiritigenin vs. isoliquiritigenin and liquiritin vs. isoliquiritin, because the isomeric precursor and fragment ion species owned different amounts of hydroxyl protons and those reactive protons could be partially or completely substituted by deuterium protons at the exposure in D2O to result in n × 1.006 mass increments. Moreover, utmost four hydrogen/deuterium exchanges occurred for a single glucosyl moiety. Thereafter, HDX-MS/MS was applied to characterize the flavonoids of Snow chrysanthemum, a precious edible herbal medicine that is rich in isomeric chalcones and dihydroflavones. Through paying special attention to the deuterium labeling styles of (de)protonated molecules as well as those featured fragment ions, five pairs of isomeric chalcones and dihydroflavones were confirmatively differentiated, in addition to that 28 flavonoids were structurally annotated by applying those well-defined mass fragmentation rules. Hence, this study offered an in-depth insight towards the flavonoids-focused characterization of Snow chrysanthemum, and more importantly, HDX-MS/MS is a superior tool to differentiate, but not limited to, isomeric chalcones and dihydroflavones.


Assuntos
Chalconas , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Hidrogênio/química , Deutério , Flavonoides , Isomerismo , Prótons , Medição da Troca de Deutério/métodos , Cromatografia Líquida , Íons
4.
Bioresour Technol ; 399: 130572, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38492651

RESUMO

Aqueous phase reforming has been explored for renewable H2 production from waste biomass. Promising results have been reported for pyrolysis bio-oil aqueous fractions (AFB), but economical assessments are needed to determine process feasibility, which requires both energy consumption minimization and optimal H2 valorization. This work compares different alternatives using process simulation and economic evaluation computational tools. Experimental results and a specific thermodynamic model are used to set mass balances. An adequate heat integration allows to reduce the process energy demand, covering the 100 % of the reactor duty. Optimal H2 unit cost is achieved if part of the produced H2 is valorized for energy self-covering and the rest is commercialized. Renewable H2 net production of c.a. 3.3 kgH2/m3 of treated AFB at a preliminary 1-2 €/kg unit cost is estimated, which can be considered as competitive with green H2, even though a case of diluted AFB is considered.


Assuntos
Hidrogênio , Polifenóis , Pirólise , Rios , Óleos de Plantas , Água , Biomassa
5.
Res Vet Sci ; 171: 105208, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38458045

RESUMO

In this study, the effect of intaking hydrogen-rich water (HRW) on the metabolic profile of Gurcu goats during the peripartum period and the survival/growth performance of kids were evaluated. Twenty-three pregnant goats were divided into two groups 21-23 days before the due date. Group 1 (G1, n = 10) was given HRW from day 21 before delivery until day 21 after delivery. Group 2 (G2, n = 13) served as the control. Blood samples were weekly taken from 21 days before delivery until 21 days after delivery. Hydrogen-rich water increased serum glucose concentration on the delivery day more than in G2 (P = 0.016). Hydrogen-rich water decreased serum total cholesterol (P = 0.02) and creatinine (P = 0.05) concentration at delivery. Group effect and time effect were significant in triglyceride (P < 0.001, P = 0.001, respectively) and albumin (P < 0.001, P = 0.002, respectively) concentration. Aspartate transaminase decreased towards the delivery day in G1 (P < 0.05). Serum non-esterified fatty acids concentration was lower in G1 than in G2, but there was no significant differences (P > 0.05). Beta-hydroxybutyric acid concentration an increased in both groups during the prepartum period, although there was no significance (P > 0.05). Hydrogen-rich water did not affect the birth weight and growth performance of the kids (P > 0.05), but it increased their survival rates and overall health, although there was no significance (P > 0.05). In conclusion, HRW may have an impact on the metabolic profiles during the peripartum period and have a positive effect on lipid profiles. Additionally, intaking HRW to goats during the peripartum period may improve the health and survival of kids and reduce their mortality.


Assuntos
Cabras , Período Periparto , Gravidez , Feminino , Animais , Suplementos Nutricionais , Hidrogênio , Água , Metaboloma
6.
Environ Pollut ; 348: 123768, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38493868

RESUMO

In this research, a sustainable substrate, termed green and long-lasting substrate (GLS), featuring a blend of emulsified substrate (ES) and modified rice husk ash (m-RHA) was devised. The primary objective was to facilitate the bioremediation of groundwater contaminated with trichloroethylene (TCE) using innovative GLS for slow carbon release and pH control. The GLS was concocted by homogenizing a mixture of soybean oil, surfactants (Simple Green™ and soya lecithin), and m-RHA, ensuring a gradual release of carbon sources. The hydrothermal synthesis was applied for the production of m-RHA production. The analyses demonstrate that m-RHA were uniform sphere-shape granules with diameters in micro-scale ranges. Results from the microcosm study show that approximately 83% of TCE could be removed (initial TCE concentration = 7.6 mg/L) with GLS supplement after 60 days of operation. Compared to other substrates without RHA addition, higher TCE removal efficiency was obtained, and higher Dehalococcoides sp. (DHC) population and hydA gene (hydrogen-producing gene) copy number were also detected in microcosms with GLS addition. Higher hydrogen concentrations enhanced the DHC growth, which corresponded to the increased DHC populations. The addition of the GLS could provide alkalinity at the initial stage to neutralize the acidified groundwater caused by the produced organic acids after substrate biodegradation, which was advantageous to DHC growth and TCE dechlorination. The addition of m-RHA reached an increased TCE removal efficiency, which was due to the fact that the m-RHA had the zeolite-like structure with a higher surface area and lower granular diameter, and thus, it resulted in a more effective initial adsorption effect. Therefore, a significant amount of TCE could be adsorbed onto the surface of m-RHA, which caused a rapid TCE removal through adsorption. The carbon substrates released from m-RHA could then enhance the subsequent dechlorination. The developed GLS is an environmentally-friendly and green substrate.


Assuntos
Água Subterrânea , Tricloroetileno , Poluentes Químicos da Água , Tricloroetileno/metabolismo , Biodegradação Ambiental , Carbono , Poluentes Químicos da Água/análise , Água Subterrânea/química , Hidrogênio , Concentração de Íons de Hidrogênio
7.
Med Phys ; 51(6): 4489-4503, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38432192

RESUMO

BACKGROUND: The increasing use of complex and high dose-rate treatments in radiation therapy necessitates advanced detectors to provide accurate dosimetry. Rather than relying on pre-treatment quality assurance (QA) measurements alone, many countries are now mandating the use of in vivo dosimetry, whereby a dosimeter is placed on the surface of the patient during treatment. Ideally, in vivo detectors should be flexible to conform to a patient's irregular surfaces. PURPOSE: This study aims to characterize a novel hydrogenated amorphous silicon (a-Si:H) radiation detector for the dosimetry of therapeutic x-ray beams. The detectors are flexible as they are fabricated directly on a flexible polyimide (Kapton) substrate. METHODS: The potential of this technology for application as a real-time flexible detector is investigated through a combined dosimetric and flexibility study. Measurements of fundamental dosimetric quantities were obtained including output factor (OF), dose rate dependence (DPP), energy dependence, percentage depth dose (PDD), and angular dependence. The response of the a-Si:H detectors investigated in this study are benchmarked directly against commercially available ionization chambers and solid-state diodes currently employed for QA practices. RESULTS: The a-Si:H detectors exhibit remarkable dose linearities in the direct detection of kV and MV therapeutic x-rays, with calibrated sensitivities ranging from (0.580 ± 0.002) pC/cGy to (19.36 ± 0.10) pC/cGy as a function of detector thickness, area, and applied bias. Regarding dosimetry, the a-Si:H detectors accurately obtained OF measurements that parallel commercially available detector solutions. The PDD response closely matched the expected profile as predicted via Geant4 simulations, a PTW Farmer ionization chamber and a PTW ROOS chamber. The most significant variation in the PDD performance was 5.67%, observed at a depth of 3 mm for detectors operated unbiased. With an external bias, the discrepancy in PDD response from reference data was confined to ± 2.92% for all depths (surface to 250 mm) in water-equivalent plastic. Very little angular dependence is displayed between irradiations at angles of 0° and 180°, with the most significant variation being a 7.71% decrease in collected charge at a 110° relative angle of incidence. Energy dependence and dose per pulse dependence are also reported, with results in agreement with the literature. Most notably, the flexibility of a-Si:H detectors was quantified for sample bending up to a radius of curvature of 7.98 mm, where the recorded photosensitivity degraded by (-4.9 ± 0.6)% of the initial device response when flat. It is essential to mention that this small bending radius is unlikely during in vivo patient dosimetry. In a more realistic scenario, with a bending radius of 15-20 mm, the variation in detector response remained within ± 4%. After substantial bending, the detector's photosensitivity when returned to a flat condition was (99.1 ± 0.5)% of the original response. CONCLUSIONS: This work successfully characterizes a flexible detector based on thin-film a-Si:H deposited on a Kapton substrate for applications in therapeutic x-ray dosimetry. The detectors exhibit dosimetric performances that parallel commercially available dosimeters, while also demonstrating excellent flexibility results.


Assuntos
Radiometria , Silício , Radiometria/instrumentação , Hidrogênio , Dosimetria in Vivo , Terapia por Raios X/instrumentação , Humanos
8.
Isotopes Environ Health Stud ; 60(2): 103-121, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38344763

RESUMO

The biogeochemical consequences of dihydrogen (H2) underground storage in porous aquifers are poorly understood. Here, the effects of nutrient limitations on anaerobic H2 oxidation of an aquifer microbial community in sediment microcosms were determined in order to evaluate possible responses to high H2 partial pressures. Hydrogen isotope analyses of H2 yielded isotope depletion in all biotic setups indicating microbial H2 consumption. Carbon isotope analyses of carbon dioxide (CO2) showed isotope enrichment in all H2-supplemented biotic setups indicating H2-dependent consumption of CO2 by methanogens or homoacetogens. Homoacetogenesis was indicated by the detection of acetate and formate. Consumption of CO2 and H2 varied along the differently nutrient-amended setups, as did the onset of methane production. Plotting carbon against hydrogen isotope signatures of CH4 indicated that CH4 was produced hydrogenotrophically and fermentatively. The putative hydrogenotrophic Methanobacterium sp. was the dominant methanogen. Most abundant phylotypes belonged to typical ferric iron reducers, indicating that besides CO2, Fe(III) was an important electron acceptor. In summary, our study provides evidence for the adaptability of subsurface microbial communities under different nutrient-deficient conditions to elevated H2 partial pressures.


Assuntos
Água Subterrânea , Microbiota , Anaerobiose , Metano/análise , Dióxido de Carbono , Compostos Férricos , Isótopos de Carbono/análise , Hidrogênio
9.
Sci Total Environ ; 917: 170489, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38301785

RESUMO

Estuaries receive substantial amounts of terrestrial dissolved organic nitrogen (tDON), which will be transported from the freshwater to the oceanic terminus through vigorous exchange processes. However, the intricate migration and transformation dynamics of tDON during this transportation, particularly at a molecular level, remain constrained. To address this knowledge gap, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was used for the analysis of DON molecular composition in the Pearl River Estuary (PRE), a river-dominated estuarine system influenced by intensified anthropogenic activities in southern China. The results showed a pronounced spatial-temporal variation in DON concentration in the study area. At the molecular level, tDON exhibited reduced unsaturation and aromaticity, coupled with an elevated abundance of DON compounds containing one­nitrogen atom (1 N-DON, 53.17 %) and compounds containing carbon, hydrogen, oxygen, nitrogen, and sulfur (CHONS) (27.46 %). It was evident that lignin was depleted while more oxygenated tannin compounds were generated in the freshwater-seawater mixing zone. This transformation is attributed to heightened biological activities, likely influenced by the priming effect of terrestrial nutrient inputs. In summer, the prevailing plume combined with biological activities in the strong mixing area and outer estuary increased the abundance of 3 N-DON molecules and a concurrent rise in the abundance of DON compounds containing only carbon, hydrogen, oxygen, and nitrogen (CHON), DON compounds containing carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus (CHONSP), and CHONS. This trend also underscores the expanding role of marine plankton and microbes in the utilization of DON compounds containing carbon, hydrogen, oxygen, nitrogen, and phosphorus (CHONP). These findings provide details of tDON transformation processes at the molecular level in a river-dominated estuary and underline the estuarine hydrodynamics involved in transporting and altering DON within the estuary.


Assuntos
Matéria Orgânica Dissolvida , Hidrodinâmica , Nitrogênio/análise , Rios , Estuários , Carbono/análise , Oxigênio/análise , Enxofre/análise , Hidrogênio/análise , Fósforo/análise
10.
Chemosphere ; 352: 141338, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331260

RESUMO

Resource recovery from solid organic wastes, such as degradable plastics, and upgrading raw bio-oil are important ways for reducing carbon and pollution emissions. Hydrodeoxygenation (HDO) is a common thermochemical treatment to upgrade crude bio-oil. In this study, in order to realize in situ HDO during the hydropyrolysis of heavy bio-oil and degradable plastics, a reduced Fe/Ce oxygen carrier (OC) was used to catalytically remove oxygen from organics under the methanol-zero valent aluminum (ZV Al) media, where the hydrogen was produced during pyrolysis instead of a direct hydrogen supply. The results showed that the reduced OC captured the oxygen from the pyrolysis products of heavy bio-oil and degradable plastic, representing the multi-selectivity of reduced OC to phenols, ketones, etc. The ZV Al system promoted the production and utilization of hydrogen, as evidenced by the increased hydrogen content in gas phase and hydrocarbon content in liquid phase. The hydrocarbon component distribution in the liquid phase increased clearly when hydropyrolysis with degradable plastics addtion, but the excess degradable plastics addition caused increasing of the liquid product viscosity, and decreasing of the liquid products yield for the higher ash content in degradable plastic, and a higher ZV Al amount was required to maintain the hydropyrolysis. Molecular dynamics simulations verified the synergistic effect of degradable plastics and bio-oil by the pyrolysis behavior in different systems and temperatures, and the pyrolysis pathways were proposed. This non-autocatalytic system realized the resource recovery and heavy bio-oil upgrading using an Fe/Ce OC.


Assuntos
Alumínio , Oxigênio , Óleos de Plantas , Metanol , Polifenóis , Hidrogênio , Biocombustíveis/análise , Temperatura Alta , Catálise , Plásticos
11.
Chemistry ; 30(22): e202400019, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38323740

RESUMO

The nonheme iron dioxygenase deoxypodophyllotoxin synthase performs an oxidative ring-closure reaction as part of natural product synthesis in plants. How the enzyme enables the oxidative ring-closure reaction of (-)-yatein and avoids substrate hydroxylation remains unknown. To gain insight into the reaction mechanism and understand the details of the pathways leading to products and by-products we performed a comprehensive computational study. The work shows that substrate is bound tightly into the substrate binding pocket with the C7'-H bond closest to the iron(IV)-oxo species. The reaction proceeds through a radical mechanism starting with hydrogen atom abstraction from the C7'-H position followed by ring-closure and a final hydrogen transfer to form iron(II)-water and deoxypodophyllotoxin. Alternative mechanisms including substrate hydroxylation and an electron transfer pathway were explored but found to be higher in energy. The mechanism is guided by electrostatic perturbations of charged residues in the second-coordination sphere that prevent alternative pathways.


Assuntos
Medicamentos de Ervas Chinesas , Hidrogênio , Ferro , Podofilotoxina/análogos & derivados , Oxirredução , Ferro/química , Hidroxilação , Hidrogênio/química , Estresse Oxidativo
12.
Environ Sci Pollut Res Int ; 31(14): 21370-21379, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38388980

RESUMO

In this article, we present the synthesis of binary CdAl4O7/CdO nanocomposites using green tea extracts and green chemistry methods for high-performance hydrogen storage. The green tea extract contains bioactive compounds (polyphenols) that act as reducing agents, which facilitate the reaction between metal ions and water. By examining the structural and morphological characteristics of the obtained substrates using scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR), it was demonstrated that the nanocomposites were successfully synthesized. We evaluated the electrochemical performance of the synthesized CdAl4O7/CdO nanocomposites using a three-electrode chronopotentiometry system. According to the results, the synthesized nanocomposites are capable of storing 1750 mAh/g of hydrogen at a constant current of 1 Amp. By using green tea extract as a natural structure-directing agent, the CdAl4O7/CdO nanocomposite can be developed more sustainably as high-performance hydrogen storage materials. Ultimately, this work contributes to the advancement of sustainable energy storage through the synthesis of a promising new material.


Assuntos
Hidrogênio , Nanocompostos , Espectroscopia de Infravermelho com Transformada de Fourier , Nanocompostos/química , Difração de Raios X , Chá/química
13.
Biointerphases ; 19(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38270483

RESUMO

In this study, we describe the fabrication of hydrogen gas sensors in the form of nanocomposites containing metal oxides such as copper oxide (CuO), multiwalled carbon nanotubes (MWCNTs), and polyaniline (PANI) using a green synthesis method. We used Macaranga indica (M. indica) leaf extract as a reducing and stabilizing agent to prepare copper oxide nanoparticles (CuONPs). The sample was analyzed using various techniques to determine its physicochemical, morphological, and elemental composition. The XRD data showed that the sample is a CuO/PANI/MWCNT nanocomposite by the best match with the reported data. SEM images revealed a uniform distribution of MWCNTs and spherical CuO nanoparticles of 30-40 nm throughout the CNT network. EDX confirmed that the prepared sample is a pure and inline combination of Cu, O, C, and N. Due to the presence of bioactive elements and PANI, we observed 17% and 25% weight loss for CuO and CuO/PANI/MWCNTs. It was found that this combination of materials can detect H2 gas in concentrations ranging from 110 to 2 ppm at temperatures of 200 and 250 °C. As H2 concentration increased, sensitivity varied from 5% to 20%, but response and recovery times were about 290 and 500 s, respectively, for 40 ppm H2 gas. A logistic function fit to Ra/Rg versus H2 was performed using Y = A2 + (A1 - A2)/(1 + (x/x0)p). The energy bands among the CuO/PANI/MWCNT heterointerfaces were used to demonstrate enhanced H2 gas-sensing properties.


Assuntos
Compostos de Anilina , Euphorbiaceae , Nanotubos de Carbono , Hidrogênio , Extratos Vegetais
14.
Am J Clin Nutr ; 119(3): 702-710, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38159728

RESUMO

BACKGROUND: Approximately 70%-100% of the Asian adult population is lactase nonpersistent (LNP). The literature shows that many individuals with the LNP-genotype can consume ≤12 g of lactose without experiencing gastrointestinal discomfort. Repetitive consumption of lactose may reduce intolerance symptoms via adaptation of the gut microbiota. OBJECTIVE: This study aimed to assess the effects of daily consumption of incremental lactose doses on microbiota composition and function, and intolerance symptoms. METHODS: Twenty-five healthy adults of Asian origin, carrying the LNP-genotype were included in this 12-wk before and after intervention trial. Participants consumed gradually increasing lactose doses from 3 to 6 g to 12 g twice daily, each daily dose of 6 g, 12 g, or 24 g being provided for 4 consecutive weeks. Participants handed-in repeated stool samples and underwent a 25 g lactose challenge hydrogen breath test (HBT) before and after the 12-wk intervention. Daily gastrointestinal symptoms and total symptom scores (TSSs) during the lactose challenge were recorded. RESULTS: A significant increase from 5.5% ± 7.6% to 10.4% ± 9.6% was observed in Bifidobacterium relative abundance after the intervention (P = 0.009), accompanied by a 2-fold increase (570 ± 269 U/g; P < 0.001) in fecal ß-galactosidase activity compared with baseline (272 ± 158 U/g). A 1.5-fold decrease (incremental area under the curve; P = 0.01) in expired hydrogen was observed during the second HBT (38 ± 35 ppm·min), compared with the baseline HBT (57 ± 38 ppm·min). There was a nonsignificant decrease in TSS (10.6 ± 8.3 before compared with 8.1 ± 7.2 after intervention; P = 0.09). Daily consumption of lactose was well tolerated, with mild to no gastrointestinal complaints reported during the intervention. CONCLUSIONS: Increased levels of Bifidobacterium indicate an adaptation of the gut microbiota upon repetitive consumption of incremental doses of lactose, which was well tolerated as demonstrated by reduced expired hydrogen concentrations during the second 25-g lactose HBT. Bifidobacteria metabolize lactose without gas production thereby potentially reducing intestinal gas formation in the gut of individuals with the LNP-genotype. This increased lactose tolerance possibly lifts the necessity to remove nutrient-rich dairy foods completely from the diet. The trial is registered at the International Clinical Trials Registry Platform: NL9516. The effect of dietary lactose in lactase nonpersistent individuals on gut microbiota.


Assuntos
Microbioma Gastrointestinal , Intolerância à Lactose , Adulto , Humanos , Intolerância à Lactose/genética , Lactase/genética , Lactose/metabolismo , beta-Galactosidase/genética , beta-Galactosidase/uso terapêutico , Genótipo , Hidrogênio/uso terapêutico , Suplementos Nutricionais , Testes Respiratórios
15.
Undersea Hyperb Med ; 50(4): 403-411, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38055881

RESUMO

Background: The pathophysiology of traumatic brain injury (TBI) is caused by the initial physical damage and by the subsequent biochemical damage (secondary brain injury). Oxidative stress is deeply involved in secondary brain injury, so molecular hydrogen therapy may be effective for TBI. Hydrogen gas shows the optimal effect at concentrations of 2% or higher, but can only be used up to 1.3% in the form of a gas cylinder mixed with oxygen gas, which may not be sufficiently effective. The partial pressure of hydrogen increases in proportion to the pressure, so hyperbaric hydrogen therapy (HBH2) is more effective than that at atmospheric pressure. Methods: A total of 120 mice were divided into three groups: TBI + non-treatment group (TBI group; n = 40), TBI + HBH2 group (n = 40), and non-TBI + non-treatment group (sham group; n = 40). The TBI and TBI + HBH2 groups were subjected to moderate cerebral contusion induced by controlled cortical impact. The TBI + HBH2 group received hyperbaric hydrogen therapy at 2 atmospheres for 90 minutes, at 30 minutes after TBI. Brain edema, neuronal cell loss in the injured hippocampus, neurological function, and cognitive function were evaluated. Results: The TBI + HBH2 group showed significantly less cerebral edema (p ≺ 0.05). Residual hippocampal neurons were significantly more numerous in the TBI + HBH2 group on day 28 (p ≺ 0.05). Neurological score and behavioral tests showed that the TBI + HBH2 group had significantly reduced hyperactivity on day 14 (p ≺ 0.01). Conclusion: Hyperbaric hydrogen therapy may be effective for posttraumatic secondary brain injury.


Assuntos
Edema Encefálico , Lesões Encefálicas Traumáticas , Lesões Encefálicas , Oxigenoterapia Hiperbárica , Ratos , Camundongos , Animais , Hidrogênio/farmacologia , Hidrogênio/uso terapêutico , Ratos Sprague-Dawley , Lesões Encefálicas/complicações , Lesões Encefálicas/terapia , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/terapia , Edema Encefálico/etiologia , Edema Encefálico/terapia , Encéfalo
16.
J Phys Chem A ; 127(51): 10807-10816, 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38108191

RESUMO

This work discusses the electron structure, antioxidative properties, and solvent contribution of two new antioxidant molecules discovered, named S10 and S11, extracted from a medicinal plant called Vatairea guianensis, found in the Amazon rain-forest. To gain a better understanding, a study using density functional theory coupled with the polarizable-continuum model and the standard 6-311++G(d,p) basis set was conducted. The results indicate that S10 has a higher antioxidant potential than S11, confirming the experimental expectations. In the gas phase, the hydrogen atom transfer route dominates the hydrogen scavenging procedure. However, in the water solvents, the antioxidant mechanism prefers the sequential proton loss electron transfer mechanism. Furthermore, the solvent plays a fundamental role in the antioxidant mechanism. The formation of an intramolecular OH···OCH3 hydrogen bond is crucial for accurately describing the hydrogen scavenging phenomenon, better aligning with the experimental data. The results suggest that the two isoflavones investigated are promising for the pharmacologic and food industries.


Assuntos
Antioxidantes , Hidrogênio , Antioxidantes/química , Solventes/química , Ligação de Hidrogênio , Hidrogênio/química , Prótons , Termodinâmica
17.
J Chem Inf Model ; 63(18): 5734-5754, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37677147

RESUMO

The presented "PubChemQC B3LYP/6-31G*//PM6" data set is composed of the electronic properties of 85,938,443 molecules, encompassing a broad spectrum of molecules from essential compounds to biomolecules with a molecular weight up to 1000. These molecules account for 94.0% of the original PubChem Compound catalog as of August 29, 2016. The electronic properties, including orbitals, orbital energies, total energies, dipole moments, and other pertinent properties, were computed by using the B3LYP/6-31G* and PM6 methods. The data set, available in three formats, namely, GAMESS quantum chemistry program files, selected JSON output files, and a PostgreSQL database, provides researchers with the ability to query molecular properties. It is further subdivided into five subdata sets for more specific data. The first two subsets encompass molecules with carbon, hydrogen, oxygen, and nitrogen with molecular weights under 300 and 500, respectively. The third and fourth subsets incorporate molecules with carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur, fluorine, and chlorine, with molecular weights under 300 and 500, respectively. The fifth subset comprises molecules with carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur, fluorine, chlorine, sodium, potassium, magnesium, and calcium, with a molecular weight of under 500. The coefficients of determination for the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gap range from 0.892 (for CHON500) to 0.803 (for the whole data set). These comprehensive results pave the way for applications in drug discovery and materials science, among others. The data sets can be accessed under the Creative Commons Attribution 4.0 International license at the following web address: https://nakatamaho.riken.jp/pubchemqc.riken.jp/b3lyp_pm6_datasets.html.


Assuntos
Cloro , Flúor , Halogênios , Carbono , Cloretos , Eletrônica , Hidrogênio , Nitrogênio , Oxigênio , Fósforo
18.
Food Res Int ; 172: 113136, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37689900

RESUMO

This study aimed to fabricate a novel codelivery system to simultaneously load ß-carotene and curcumin in a controlled and synergistic manner. We hypothesized that the aggregates of octenylsuccinated Gastrodia elata starch (OSGES) could efficiently load and control the release of ß-carotene and curcumin in combination. Mechanisms underlying the self-assembly of OSGES, coloading, and corelease of ß-carotene and curcumin by relevant aggregates were studied. The OSGES could form aggregates with a size of 120.2 nm containing hydrophobic domains surrounded by hydrophilic domains. For coloading, the increased solubilities were attributed to favorable interactions between ß-carotene and curcumin as well as interactions with octenyl and starch moieties via hydrophobic and hydrogen-bond interactions, respectively. The ß-carotene and curcumin molecules occupied the interior and periphery of hydrophobic domains of OSGES aggregates, respectively, and they did not exist in isolation but interacted with each other. The ß-carotene and curcumin combination-loaded OSGES aggregates with a size of 310.5 nm presented a more compact structure than ß-carotene-only and curcumin-only loaded OSGES aggregates with sizes of 463.5 and 202.9 nm respectively, suggesting that a transition from a loose cluster to a compact cluster was accompanied by coloading. During in vitro digestion, the joint effect of ß-carotene and curcumin prolonged their release and increased their bioaccessibility due to competition between favorable hydrophobic and hydrogen-bond interactions and the unfavorable structure erosion and relaxation of the loaded aggregates. Therefore, OSGES aggregates were designed for the codelivery of ß-carotene and curcumin, indicating their potential to be applied in functional foods and dietary supplements.


Assuntos
Curcumina , Gastrodia , Preparações de Ação Retardada , beta Caroteno , Amido , Hidrogênio
19.
J Environ Manage ; 346: 119031, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37741194

RESUMO

This study aimed at investigating the biohydrogen and biomethane potential of co-digestion from palm oil mill effluent (POME) and concentrated latex wastewater (CLW) in a two-stage anaerobic digestion (AD) process under thermophilic (55 ± 3 °C) and at an ambient temperature (30 ± 3 °C) conditions, respectively. The batch experiments of POME:CLW mixing ratios of 100:0, 70:30, 50:50, 30:70, and 0:100 was investigated with the initial loadings at 10 g-VS/L. The highest hydrogen yield of 115.57 mLH2/g-VS was obtained from the POME: CLW mixing ratio of 100:0 with 29.0 of C/N ratio. While, the highest subsequent methane production yield of 558.01 mLCH4/g-VS was achieved from hydrogen effluent from POME:CLW mixing ratio of 70:30 0 with 21.8 of C/N ratio. This mixing ratio revealed the highest synergisms of about 9.21% and received maximum total energy of 19.70 kJ/g-VS. Additionally, continuous hydrogen and methane production were subsequently performed in a series of continuous stirred tank reactor (CSTR) and up-flow anaerobic sludge blanket reactor (UASB) to treat the co-substate. The results indicated that the highest hydrogen yield of POME:CLW mixing ratio at 70:30 of 95.45 mL-H2/g-VS was generated at 7-day HRT, while methane production was obtained from HRT 15 days with a yield of 204.52 mL-CH4/g-VS. Thus, the study indicated that biogas production yield of CLW could be enhanced by co-digesting with POME. In addition, the two-stage AD model under anaerobic digestion model no. 1 (ADM-1) framework was established, 9.10% and 2.43% of error fitting of hydrogen and methane gas between model simulation data and experimental data were found. Hence, this research work presents a novel approach for optimization and feasibility for co-digestion of POME with CLW to generate mixed gaseous biofuel potentially.


Assuntos
Óleos de Plantas , Águas Residuárias , Óleo de Palmeira , Látex , Hidrogênio , Anaerobiose , Reatores Biológicos , Metano , Biocombustíveis
20.
Anal Sci ; 39(12): 2075-2083, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37665546

RESUMO

Geographical discrimination of mulberry leaves is very important for their efficacy and quality as a traditional Chinese medicine. Stable hydrogen, oxygen, and carbon isotope ratios were measured in 292 mulberry leaves collected at 2 growth stages in 2 seasons from 8 regions of China. A stepwise linear discriminant analysis (LDA) approach were proposed to combine with stable isotope technology to tracing the origin of mulberry leaves. The results showed that leaves sampled in autumn were extremely depleted in 2H and 18O and slightly enriched in 13C compared with leaves sampled in summer, correlated with the effect of season, transpiration and photorespiration on stable isotopes. δ2H and δ18O of the leaves were enriched during the growth process. The overall discrimination accuracy of the autumn tender model was 81%, demonstrating that analysis of δ2H, δ18O, and δ13C is a promising technique for tracing the geographical origin of mulberry leaves, although season, growth stage and number of samples affect the accuracy of discrimination.


Assuntos
Morus , Oxigênio , Isótopos de Carbono/análise , Hidrogênio , Isótopos de Oxigênio , Espectrometria de Massas/métodos
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