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Medicinas Complementares
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1.
J. oral res. (Impresa) ; 13(1): 47-58, mayo 29, 2024. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1563181

RESUMO

Introduction: Periodontal inflammation causes dysbiosis and change in the microbiota. Nonsurgical periodontal therapy (NSPT) helps in removal of plaque and restoring periodontal health. Various adjunctive therapy like use of mouthwash helps in maintenance of periodontal health and reducing inflammatory load. Materials and Methods: A total of 108 subjects diagnosed with type 2 diabetes mellitus and periodontitis were divided into three groups: Group 1 received NSPT and rinsing with 0.2% chlorhexidine mouthwash for 3 months, Group 2 received NSPT and rinsing with 1.5% hydrogen peroxide mouthwash for 3 months, Group 3- received NSPT only (control group). The clinical parameters measured included Plaque Index (PI), Gingival Index (GI), Bleeding on probing (BOP) and probing (PD) at baseline, 1, 2, 3 months follow up. Salivary interleukin 1ßlevels were measured at baseline and 3 months interval. Results: Group 1, 2 and 3 showed significant reduction in PI, GI, BOP and PD at 1 and 3 months follow up (p<0.05). However, Intergroup comparison of clinical parameters showed significant reduction in group 1 and 2 when compared with group 3 (p<0.05). Salivary interleukin 1-ß levels showed significant reduction from baseline to 3 months in all the three groups and intergroup comparison didn't show any significant changes, (p>0.05). Conclusions: Hydrogen peroxide mouthwash as an adjunct to NSPT can be considered as a safe and effective measure to reduce periodontal inflammation in type 2 diabetes mellitus patients with chronic periodontitis.


Introducción: La inflamación periodontal causa disbiosis y cambios en la microbiota. La terapia periodontal no quirúrgica (NSPT) ayuda a eliminar la placa y restaurar la salud periodontal. Diversas terapias complementarias, como el uso de enjuague bucal, ayudan a mantener la salud periodontal y reducir la carga inflamatoria. Materiales y Métodos: Un total de 108 sujetos diagnosticados con diabetes mellitus tipo 2 y periodontitis se dividieron en tres grupos: el grupo 1 recibió NSPT y enjuague con enjuague bucal de clorhexidina al 0,2% durante 3 meses, el grupo 2 recibió NSPT y enjuague con enjuague bucal de peróxido de hidrógeno al 1,5% durante 3 meses, y el Grupo 3 recibió NSPT únicamente (grupo de control). Los parámetros clínicos medidos fueron el índice de placa (PI), el índice gingival (GI), el sangrado al sondaje (BOP) y al sondaje (PD) al inicio del estudio, 1, 2, y 3 meses de seguimiento. Los niveles de interleucina 1ß en saliva se midieron al inicio y a los 3 meses. Resultado: Los grupos 1, 2 y 3 mostraron una reducción significativa en IP, GI, BOP y PD al mes y 3 meses de seguimiento (p<0,05). Sin embargo, la comparación intergrupal de los parámetros clínicos mostró una reducción significativa en los grupos 1 y 2 en comparación con grupo 3 (p<0,05). Los niveles de interleucina 1-ß salival mostraron una reducción significativa desde el inicio hasta los 3 meses en los tres grupos y la comparación entre grupos no mostró ningún cambio significativo (p>0,05). Conclusión: El enjuague bucal con peróxido de hidrógeno como complemento de la NSPT puede considerarse una medida segura y eficaz para reducir la inflamación periodontal en pacientes con diabetes mellitus tipo 2 y periodontitis crónica.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Clorexidina/uso terapêutico , Periodontite Crônica/terapia , Peróxido de Hidrogênio/uso terapêutico , Antissépticos Bucais/uso terapêutico , Saúde Bucal
2.
J Biomol Struct Dyn ; : 1-15, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651748

RESUMO

The management of oxidative stress-related disorders has garnered significant interest, particularly in the exploration of medicinal plants possessing potent antioxidant activities. This study was undertaken to evaluate the antioxidant activity of Mondia whitei (MW) and Guibourtia tessmannii (GT) against H2O2-induced cytotoxicity in PC3 cells. The phytochemical composition of MW and GT was determined by GC-MS analysis. Total phenolic (TP) and total flavonoid (TF) contents were quantified by Folin Ciocalteu and AlCl3 methods, respectively. The antioxidant potential of the extracts was determined using the DPPH and ABTS+ radicals scavenging method, as well as cupric and ferric reducing capacity assay. Moreover, all phytocompounds were docked against acetylcholinesterase (AChE) and glutathione S-transferase (GST) using ArgusLab, and results were analyzed using the BIOVIA Discovery Studio Visualizer 2021 client. MW and GT comprised 20 and 22 compounds, respectively. GT exhibited higher TP and TF contents (210.70 ± 12.7; 12.61 ± 1.3 GAE/g DW) compared to MW (132.59 ± 12.59; 5.53 ± 1.3 mg of GAE/g DW). Both MW and GT demonstrated substantial antioxidant activity, with GT proving to be more effective in preventing H2O2-induced cytotoxicity. For instance, MW and GT significantly (p < .001) increased the DPPH, ABTS+, and cupric activity, compared with the H2O2 group. All compounds identified in MW and GT exhibited a strong binding affinity against AChE and GST. Drug likeness and toxicity of all phytocompounds were under the acceptable norms of Lipinski's rule. In conclusion, these plants could be effective candidates for the management/treatment of oxidative stress-related disorders.Communicated by Ramaswamy H. Sarma.

3.
Methods Mol Biol ; 2798: 213-221, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38587746

RESUMO

Catalase, a pivotal enzyme in plant antioxidative defense mechanisms, plays a crucial role in detoxifying hydrogen peroxide, a reactive oxygen species (ROS). In this chapter, a comparative analysis of catalase activity was conducted using two distinct methodologies: spectrophotometry and non-denaturing polyacrylamide gel electrophoresis (PAGE). The spectrophotometric approach allowed the quantification of catalase activity by measuring the breakdown rate of hydrogen peroxide, while native PAGE enabled the separation and visualization of catalase isozymes, based on their native molecular weight and charge characteristics, and specific staining assay. Both methods provide valuable insights into catalase activity, offering complementary information on the enzyme's functional diversity and distribution within different plant tissues. This study integrates different techniques, previously described, to comprehensively elucidate the role of catalase in plant metabolism. Furthermore, it provides the possibility of obtaining a holistic understanding of antioxidant defense mechanisms by considering both total activity and isoenzyme distribution of catalase enzyme.


Assuntos
Antioxidantes , Peróxido de Hidrogênio , Catalase , Eletroforese em Gel de Poliacrilamida Nativa , Espectrofotometria
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.
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
7.
Phytother Res ; 38(5): 2388-2405, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38430052

RESUMO

The prevalence of overweight and obesity has progressively increased in the last few years, becoming a real threat to healthcare systems. To date, the clinical management of body weight gain is an unmet medical need, as there are few approved anti-obesity drugs and most require an extensive monitoring and vigilance due to risk of adverse effects and poor patient adherence/persistence. Growing evidence has shown that the gasotransmitter hydrogen sulfide (H2S) and, therefore, H2S-donors could have a central role in the prevention and treatment of overweight/obesity. The main natural sources of H2S-donors are plants from the Alliaceae (garlic and onion), Brassicaceae (e.g., broccoli, cabbage, and wasabi), and Moringaceae botanical families. In particular, polysulfides and isothiocyanates, which slowly release H2S, derive from the hydrolysis of alliin from Alliaceae and glucosinolates from Brassicaceae/Moringaceae, respectively. In this review, we describe the emerging role of endogenous H2S in regulating adipose tissue function and the potential efficacy of natural H2S-donors in animal models of overweight/obesity, with a final focus on the preliminary results from clinical trials. We conclude that organosulfur-containing plants and their extracts could be used before or in combination with conventional anti-obesity agents to improve treatment efficacy and reduce inflammation in obesogenic conditions. However, further high-quality studies are needed to firmly establish their clinical efficacy.


Assuntos
Sulfeto de Hidrogênio , Obesidade , Sobrepeso , Humanos , Obesidade/tratamento farmacológico , Animais , Sobrepeso/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Fármacos Antiobesidade/farmacologia , Glucosinolatos/farmacologia , Glucosinolatos/química , Isotiocianatos/farmacologia , Brassicaceae/química
8.
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
9.
Microorganisms ; 12(2)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38399731

RESUMO

Some insertion sequence (IS) elements were actively transposed using oxidative stress conditions, including gamma irradiation and hydrogen peroxide treatment, in Deinococcus geothermalis, a radiation-resistant bacterium. D. geothermalis wild-type (WT), sigma factor gene-disrupted (∆dgeo_0606), and LysR gene-disrupted (∆dgeo_1692) mutants were examined for IS induction that resulted in non-pigmented colonies after gamma irradiation (5 kGy) exposure. The loss of pigmentation occurred because dgeo_0524, which encodes a phytoene desaturase in the carotenoid pathway, was disrupted by the transposition of IS elements. The types and loci of the IS elements were identified as ISDge2 and ISDge6 in the ∆dgeo_0606 mutant and ISDge5 and ISDge7 in the ∆dgeo_1692 mutant, but were not identified in the WT strain. Furthermore, 80 and 100 mM H2O2 treatments induced different transpositions of IS elements in ∆dgeo_0606 (ISDge5, ISDge6, and ISDge7) and WT (ISDge6). However, no IS transposition was observed in the ∆dgeo_1692 mutant. The complementary strain of the ∆dgeo_0606 mutation showed recovery effects in the viability assay; however, the growth-delayed curve did not return because the neighboring gene dgeo_0607 was overexpressed, probably acting as an anti-sigma factor. The expression levels of certain transposases, recognized as pivotal contributors to IS transposition, did not precisely correlate with active transposition in varying oxidation environments. Nevertheless, these findings suggest that specific IS elements integrated into dgeo_0524 in a target-gene-deficient and oxidation-source-dependent manner.

10.
J Environ Manage ; 354: 120328, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38354615

RESUMO

This study aims to evaluate whether different doses of Bacillus-based inoculum inoculated in chicken manure and sawdust composting will provide distinct effects on the co-regulation of ammonia (NH3) and hydrogen sulfide (H2S), nutrient conversions and microbial topological structures. Results indicate that the Bacillus-based inoculum inhibits NH3 emissions mainly by regulating bacterial communities, while promotes H2S emissions by regulating both bacterial and fungal communities. The inoculum only has a little effect on total organic carbon (TOC) and inhibits total sulfur (TS) and total phosphorus (TP) accumulations. Low dose inoculation inhibits total potassium (TK) accumulation, while high dose inoculation promotes TK accumulation and the opposite is true for total nitrogen (TN). The inoculation slightly affects the bacterial compositions, significantly alters the fungal compositions and increases the microbial cooperation, thus influencing the compost substances transformations. The microbial communities promote ammonium nitrogen (NH4+-N), TN, available phosphorus (AP), total potassium (TK) and TS, but inhibit nitrate nitrogen (NO3--N), TP and TK. Additionally, the bacterial communities promote, while the fungal communities inhibit the nitrite nitrogen (NO2--N) production. The core bacterial and fungal genera regulate NH3 and H2S emissions through the secretions of metabolic enzymes and the promoting or inhibiting effects on NH3 and H2S emissions are always opposite. Hence, Bacillus-based inoculum cannot regulate the NH3 and H2S emissions simultaneously.


Assuntos
Bacillus , Compostagem , Microbiota , Animais , Bacillus/metabolismo , Galinhas , Esterco/microbiologia , Odorantes , Amônia/análise , Nitrogênio/análise , Bactérias/metabolismo , Nutrientes , Fósforo , Potássio , Solo/química
11.
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
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.
J Colloid Interface Sci ; 663: 1-8, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38387182

RESUMO

We developed a new method to synthesize polyethylene glycol modified ultra small iron embedded in mesoporous carbon nanoparticle (C/Fe-PEG NP) for hydrogen (H2) assisted photothermal synergistic therapy. Herein, we use a simple in-situ reduction method to obtain the C/Fe NP in one-step carbonizing process, which is further modified by the biocompatible polyethylene glycol (PEG) on the surface of C/Fe NP to acquire high stability in physiological solutions. Utilizing the excellent photothermal property from the mesoporous carbon and the controllable H2 release property in the weakly acidic tumor microenvironment by the ultra-small Fe, the obtained C/Fe-PEG NPs can effective kill the cancer cells, meanwhile, protect normal cells without drugs. This selective anti-cancer mechanism of C/Fe-PEG NPs may because the produced H2 selective change the mitochondrial energy metabolism. In vivo results prove that the C/Fe-PEG NPs achieve excellent tumor ablation therapeutic effect and normal tissue protecting ability benefit from the H2-assisted photothermal therapy, promising the use of novel nanomaterials with more safety method for future cancer therapy.


Assuntos
Nanopartículas , Terapia Fototérmica , Ferro/farmacologia , Fototerapia , Polietilenoglicóis , Carbono/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/uso terapêutico
14.
Tree Physiol ; 44(3)2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38349798

RESUMO

Peumus boldus, a tree native to Chile, is extensively used for medicinal purposes due to its richness in alkaloids and antioxidant polyphenols. A species of galling insect, Dasineura sp. induces structural and chemical changes on P. boldus stems while its galls are established and developed. Taking into account the antioxidant properties of P. boldus polyphenols, it would be expected that Dasineura sp. induces changes in the accumulation sites, chemical profile, and antioxidant activity of the P. boldus stem polyphenols, related to different reactive oxygen species (ROS) production levels during gall development. Dasineura sp. induces changes in the accumulation sites of total polyphenols, flavonols, and lignin, redirecting their accumulation toward the sites of greatest production of H2O2 and O2.-. Although changes in total polyphenol content would be expected, this did not vary significantly between non-galled and galled stems. However, the galling insect induced changes in the profile and concentration of soluble polyphenols, leading to the gall extracts' antioxidant capacity decreasing significantly during the maturation and senescence stages. Additionally, during the maturation stage, lignin deposition increases in the more peripheral gall tissues, which also contributes to ROS dissipation. The differences in the different gall developmental stages' antioxidant activity could be related to the identity and concentration of phenolic compounds in each gall extract, rather than to the total phenol content. Regardless of the mechanisms involved, the dissipation of the ROS generated by Dasineura sp. activity occurs, restoring the redox balance in galls and guaranteeing the success of the inducer.


Assuntos
Antioxidantes , Peumus , Polifenóis , Peumus/química , Lignina , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Fenóis , Tumores de Planta
15.
Acta Crystallogr C Struct Chem ; 80(Pt 2): 43-48, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38281183

RESUMO

Cedrol-like compounds are of pharmacological interest due to their diverse range of medicinal effects and are used globally in traditional medicines and cosmetics. Many cedrol tautomers are known from molecular studies but few have been studied in crystalline form by X-ray diffraction. Acicular white crystals collected from the wood of eastern red cedar (Juniperus virginiana) are determined to be (+)-cedrol hemihydrate, namely, (1S,2R,5S,7R,8R)-2,6,6,8-tetramethyltricyclo[5.3.1.01,5]undecan-8-ol hemihydrate, C15H26O·0.5H2O, a novel packing of two unique cedrol molecules (Z' = 2) with a single water molecule [space group P212121; a = 6.1956 (1), b = 14.5363 (1), and c = 30.9294 (4) Å]. The hydrogen bonding forms a one-dimensional spiral chain running along the a axis, following the chirality of the cedrol molecule, through hydrogen-bonding interactions with a right-handed helical configuration in graph-set notation Δ-C33(6) > a > c > b. The crystal packing and symmetry are different from crystalline isocedrol due to the different hydrogen-bonding geometry.

16.
Biomedicines ; 12(1)2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38255223

RESUMO

Hydrogen gas, renowned for its antioxidant properties, has emerged as a novel therapeutic agent with applications across various medical domains, positioning it as a potential adjunct therapy in transplantation. Beyond its antioxidative properties, hydrogen also exerts anti-inflammatory effects by modulating pro-inflammatory cytokines and signaling pathways. Furthermore, hydrogen's capacity to activate cytoprotective pathways bolsters cellular resilience against stressors. In recent decades, significant advancements have been made in the critical medical procedure of transplantation. However, persistent challenges such as ischemia-reperfusion injury (IRI) and graft rejection continue to hinder transplant success rates. This comprehensive review explores the potential applications and therapeutic implications of hydrogen in transplantation, shedding light on its role in mitigating IRI, improving graft survival, and modulating immune responses. Through a meticulous analysis encompassing both preclinical and clinical studies, we aim to provide valuable insights into the promising utility of hydrogen as a complementary therapy in transplantation.

17.
J Colloid Interface Sci ; 659: 474-485, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38183813

RESUMO

Reactive chemical bonds are associated with the generation of therapeutic radicals and gases under internal-external stimuli, which are highly attractive for cancer treatments. However, designing multifunctional nanostructures that incorporate multiple chemical bonds remains a significant challenge. Herein, novel core-shell nanobombs integrating azo (NN) and tetrasulfide bonds (SSSS) have been constructed with sensitive ignition by both near-infrared (NIR) laser and tumor microenvironments (TME) for treating colorectal tumors. The nanobombs (GNR/AIPH@MON@PVP, GAMP) were prepared by the in-situ growth of tetrasulfide-contained mesoporous organosilica nanoshell (MON) on gold nanorods (GNR) as the photothermal initiator, the load of azo compound (AIPH) as the radical producer and polymer modification. Upon NIR irradiation, the GNR core exhibits stable and high photothermal effects because of the passivation of the MON shell, leading to the thermal ablation of cancer cells. Simultaneously, the local hyperthermia ignites AIPH to release alkyl radicals to cause extensive oxidative stress without oxygen dependence. Moreover, the MON shell can be gradually decomposed in a reduced environment and release therapeutic H2S gas because of the cleavage of SSSS bonds by the glutathione (GSH) overexpressed in TME, causing mitochondrial injury. Owing to multifunctional functions, the GAMP significantly inhibits the growth rate of tumors upon NIR irradiation and achieves the highest efficacy among treatments. Therefore, this study presents activatable nanoagents containing multiple chemical bonds and provides insights into developing comprehensive antitumor strategies.


Assuntos
Neoplasias Colorretais , Hipertermia Induzida , Nanopartículas , Neoplasias , Humanos , Terapia Combinada , Neoplasias/tratamento farmacológico , Estresse Oxidativo , Neoplasias Colorretais/terapia , Linhagem Celular Tumoral , Nanopartículas/química , Microambiente Tumoral
18.
Adv Mater ; 36(5): e2308774, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37917791

RESUMO

Near-infrared (NIR) laser-induced photoimmunotherapy has aroused great interest due to its intrinsic noninvasiveness and spatiotemporal precision, while immune evasion evoked by lactic acid (LA) accumulation severely limits its clinical outcomes. Although several metabolic interventions have been devoted to ameliorate immunosuppression, intracellular residual LA still remains a potential energy source for oncocyte proliferation. Herein, an immunomodulatory nanoadjuvant based on a yolk-shell CoP/NiCoP (CNCP) heterostructure loaded with the monocarboxylate transporter 4 inhibitor fluvastatin sodium (Flu) is constructed to concurrently relieve immunosuppression and elicit robust antitumor immunity. Under NIR irradiation, CNCP heterojunctions exhibit superior photothermal performance and photocatalytic production of reactive oxygen species and hydrogen. The continuous heat then facilitates Flu release to restrain LA exudation from tumor cells, whereas cumulative LA can be depleted as a hole scavenger to improve photocatalytic efficiency. Subsequently, potentiated photocatalytic therapy can not only initiate systematic immunoreaction, but also provoke severe mitochondrial dysfunction and disrupt the energy supply for heat shock protein synthesis, in turn realizing mild photothermal therapy. Consequently, LA metabolic remodeling endows an intensive cascade treatment with an optimal safety profile to effectually suppress tumor proliferation and metastasis, which offers a new paradigm for the development of metabolism-regulated immunotherapy.


Assuntos
Nanopartículas , Neoplasias , Humanos , Fototerapia , Luz , Neoplasias/tratamento farmacológico , Imunoterapia , Lactatos/uso terapêutico , Linhagem Celular Tumoral , Nanopartículas/química
19.
Adv Sci (Weinh) ; 11(7): e2304603, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38070182

RESUMO

Provision of atomic hydrogen by hydrogen dissociation catalysts only moderately accelerates the hydrogenation rate of magnesium. They shed light on this well-known but technically challenging fact through a combined approach using an unconventional surface science technique together with Density Functional Theory (DFT) calculations. The calculations demonstrate the drastic electronic structure changes during transformation of Mg to MgH2 , which make fractional hydrogen coverage on the surface, as well as substoichiometric hydrogen content in the bulk energetically unfavorable. Reflecting Electron Energy Loss Spectroscopy (REELS) is used to measure the surface and bulk plasmon during hydrogen sorption in magnesium. The measurements show that the hydrogenation proceeds via the growth of magnesium hydride without the presence of chemisorbed hydrogen on the metallic magnesium surface exactly as indicated by the calculations. This is due to the low stability of sub-stoichiometric amounts of chemisorbed H correlating with the unfavorable charge state of Mg. They are merely bound to the unchanged adjacent Mg layers, thereby explaining the failure of classical hydrogenation catalysts, which effectively only hydrogenate Mg in their direct vicinity. The acceleration of hydrogen sorption kinetics in Mg must affect the polarization in the interface between Mg and MgH2 during hydrogenation.

20.
Talanta ; 269: 125461, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38056416

RESUMO

Gastrodia elata Bl. is a widely used traditional Chinese medicine known for its medicinal properties. However, during the drying process, G. elata is often fumigated with sulfur to prevent corrosion and improve its appearance. Sulfur-fumigation can result in a reduction in the effective components of the herb and can also be hazardous to human health due to the remaining sulfur dioxide. Sulfur-fumigation of G. elata poses a significant challenge to both end-users and researchers. The detection of p-hydroxybenzyl hydrogen sulfite (p-HS) is a useful tool in determining whether G. elata has been fumigated with sulfur. Unfortunately, the current method for detecting p-HS is costly and requires sophisticated instruments. Therefore, there is a need to develop a more cost-effective and user-friendly method for the detection of p-HS. This study utilized the Capture-SELEX technique to screen high-affinity aptamers for p-HS, which were subsequently characterized by isothermal titration calorimetry (ITC). An aptamer sequence (seq 6) with a high affinity of Kd = 26.5 µM was obtained following 8 rounds of selection against p-HS. With the aptamer serving as the recognition element and gold nanoparticles as the colorimetric indicator, a simple and efficient colorimetric sensor was developed for the specific detection of p-HS. This detection method exhibited a limit of detection of 1 µg/ml, while the p-HS recoveries demonstrated a range of between 88.5 % and 105 % for samples of G. elata obtained in the market. In summary, the aptamer exhibited a high affinity for p-HS, and the sensor developed through the use of a colloidal gold detector based on nucleic acid aptamer can be utilized for rapid detection of sulfur-fumigated G. elata. With these findings, this research paper provides valuable scientific insights and highlights significant potential for future studies in this area.


Assuntos
Medicamentos de Ervas Chinesas , Gastrodia , Nanopartículas Metálicas , Humanos , Gastrodia/química , Medicamentos de Ervas Chinesas/química , Ouro , Enxofre/química
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