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1.
J Ethnopharmacol ; 337(Pt 2): 118916, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39393560

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The bark of Ailanthus altissima (Mill.) Swingle (BAA), a widely used Chinese medicinal herb in traditional remedies for bowel disorders, has yet to be explored in the context of ulcerative colitis (UC), and its therapeutic mechanisms remain unclear. AIM OF THE STUDY: This study integrated network pharmacology and experimental validation to investigate the effects and underlying mechanisms of BAA in treating UC. MATERIALS AND METHODS: First, UPLC-MS/MS analysis was employed to identify the chemical constituents of BAA. Network pharmacology was then applied to analyze the potential mechanisms of BAA based on these identified compounds. Lastly, a dextran sulfate sodium (DSS)-induced UC mouse model was utilized to assess BAA's therapeutic efficacy, with Western blotting performed to examine changes in protein expression within the key pathway influenced by BAA. RESULTS: UPLC-MS/MS and SwissADME analysis identified 223 active compounds in BAA. Network pharmacology suggested that the PI3K/AKT pathway may serve as a primary mechanism by which BAA exerts its anti-UC effects. In the DSS-induced UC mouse model, BAA significantly mitigated colonic injury, reduced DAI scores, and promoted weight recovery in mice. Additionally, BAA downregulated pro-inflammatory cytokines, including TNF-α, IL-1ß, and IL-6, thereby suppressing inflammatory responses in the colon. Western blot analysis further demonstrated that BAA primarily inhibited the PI3K/AKT pathway in UC mouse colon tissue. CONCLUSION: This study highlights that BAA effectively reduces colonic inflammation and preserves intestinal mucosal integrity, likely through the inhibition of PI3K/AKT pathway activity, positioning it as a potential treatment for UC.

2.
Chem Commun (Camb) ; 60(77): 10760-10763, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39248440

RESUMEN

The chemical behaviors of alkali and alkaline earth metal hydrides including LiH, KH, MgH2, CaH2, and BaH2 under nitrogen plasma differ significantly from one another, exhibiting an ammonia production trend that contrasts with that observed under thermal conditions. A prominent feature of KH is its ability to facilitate plasma-assisted N2 fixation without generating H2 byproduct, showing high atomic economy in utilization of hydride ions for N2 reduction.

3.
J Virol ; 98(8): e0192923, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39078152

RESUMEN

Hepatitis B virus (HBV) expresses co-terminal large (L), middle (M), and small (S) envelope proteins containing preS1/preS2/S, preS2/S, and S domain alone, respectively. S and preS1 domains mediate sequential virion attachment to heparan sulfate proteoglycans and sodium taurocholate cotransporting polypeptide (NTCP), respectively, which can be blocked by anti-S and anti-preS1 antibodies. How anti-preS2 antibodies neutralize HBV infectivity remains enigmatic. The late stage of chronic HBV infection often selects for mutated preS2 translation initiation codon to prevent M protein expression, or in-frame preS2 deletions to shorten both L and M proteins. When introduced to infectious clone of genotype C or D, both M-minus mutations and most 5' preS2 deletions sustained virion production. Such mutant progeny viral particles were infectious in NTCP-reconstituted HepG2 cells. Neutralization experiments were performed on the genotype D clone. Although remaining susceptible to anti-preS1 and anti-S neutralizing antibodies, M-minus mutants were only partially neutralized by two anti-preS2 antibodies tested while preS2 deletion mutants were resistant. By infection experiments using viral particles with lost versus increased M protein expression, or a neutralization escaping preS2 deletion only present on L or M protein, we found that both full-length L and M proteins contributed to virus neutralization by the two anti-preS2 antibodies. Thus, immune escape could be a driving force for the selection of M-minus mutations, and especially preS2 deletions. The fact that both L and M proteins could mediate neutralization by anti-preS2 antibodies may shed light on the underlying molecular mechanism.IMPORTANCEThe large (L), middle (M), and small (S) envelope proteins of hepatitis B virus (HBV) contain preS1/preS2/S, preS2/S, and S domain alone, respectively. The discovery of heparan sulfate proteoglycans and sodium taurocholate cotransporting polypeptide (NTCP) as the low- and high-affinity HBV receptors could explain neutralizing potential of anti-S and anti-preS1 antibodies, respectively, but how anti-preS2 neutralizing antibodies work remains enigmatic. In this study, we found two M-minus mutants in the context of genotype D partially escaped two anti-preS2 neutralizing antibodies in NTCP-reconstituted HepG2 cells, while several naturally occurring preS2 deletion mutants escaped both antibodies. By point mutations to eliminate or enhance M protein expression, and by introducing preS2 deletion selectively to L or M protein, we found binding of anti-preS2 antibodies to both L and M proteins contributed to neutralization of wild-type HBV infectivity. Our finding may shed light on the possible mechanism(s) whereby anti-preS2 antibodies neutralize HBV infectivity.


Asunto(s)
Anticuerpos Neutralizantes , Antígenos de Superficie de la Hepatitis B , Virus de la Hepatitis B , Proteínas del Envoltorio Viral , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/genética , Humanos , Antígenos de Superficie de la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/genética , Proteínas del Envoltorio Viral/inmunología , Proteínas del Envoltorio Viral/genética , Anticuerpos Neutralizantes/inmunología , Células Hep G2 , Eliminación de Secuencia , Simportadores/inmunología , Simportadores/genética , Precursores de Proteínas/inmunología , Precursores de Proteínas/genética , Anticuerpos contra la Hepatitis B/inmunología , Hepatitis B/inmunología , Hepatitis B/virología , Genotipo , Evasión Inmune , Transportadores de Anión Orgánico Sodio-Dependiente/genética , Transportadores de Anión Orgánico Sodio-Dependiente/inmunología , Transportadores de Anión Orgánico Sodio-Dependiente/metabolismo , Virión/inmunología
4.
Genes Dis ; 11(5): 100938, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39071112

RESUMEN

IL-17 A is a promoter of colorectal cancer initiation and progression. Narciclasine is a polyhydroxy alkaloid compound isolated from Narcissus plants, which has potent anti-inflammatory and antitumor actions. The effects of narciclasine on colorectal tumors were evaluated, with a focus on IL-17 A. Narciclasine reduced the growth of HCT-116 and SW-480 colon cancer cells in vitro and in vivo in murine xenografts. The results of flow cytometry on JC-1 and Annexin V/PI revealed that narciclasine significantly reduced the mitochondrial membrane potential and induced apoptosis, findings confirmed by western blotting results of reduced Bcl-2 and enhanced Bax expression, as well as accumulation of cleaved Caspase-3, Caspase-8, Caspase-9, and cytoplasmic Cytochrome-c. After narciclasine incubation, IL-17 A, Act1, and TRAF6 were down-regulated, while p-P65 (Ser536) accumulated in the cytoplasm, a finding confirmed by laser scanning confocal microscopy. IL17A substitution could partly reverse these narciclasine effects while they were elevated by IL17A silencing. Moreover, IL-17 A, Act1, and TRAF6 were significantly expressed to greater extents in human colorectal cancer compared to normal adjacent tissue specimens and were closely linked with a poor prognosis. This study provided evidence that narciclasine may be a useful therapeutic drug for colorectal cancer treatment through its actions in down-regulating the L-17A/Act1/TRAF6/NF-κB anti-apoptotic signaling pathway.

5.
Ear Nose Throat J ; : 1455613241261457, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877652

RESUMEN

Pleomorphic adenoma (PA) represents the most frequently occurring benign tumor within both major and minor salivary glands. However, in rare instances, nasal PA is an epithelial-derived borderline tumor, often originating from the nasal septum. Diagnosis usually relies on histopathological analysis. Under general anesthesia, these rare nasal tumors can be completely resected via endoscopic surgery. This article reports a case of PA originating from the nasal septum in a 49-year-old patient presenting with nasal congestion, along with a brief review of the current literature. The diagnostic nasal endoscopic examination showed a pink neoplastic mass in the left nasal cavity. Subsequent radiologic examination demonstrated a soft tissue mass in the anterior part of the nasal septum. After complete resection under nasal endoscopy, histopathological examination confirmed it as PA. Fortunately, no related complications occurred perioperatively and postoperatively. After surgery, performing a thorough examination with nasal endoscopy and scheduling regular follow-ups are crucial steps to prevent local recurrence.

6.
J Asian Nat Prod Res ; 26(11): 1292-1304, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38885306

RESUMEN

Three new prenylated C6-C3 compounds (1-3), together with two known prenylated C6-C3 compounds (4-5) and one known C6-C3 derivative (6), were isolated from the roots of Illicium brevistylum A. C. Smith. The structures of 1-3 were elucidated by spectroscopic methods including 1D and 2D NMR, HRESIMS, CD experiments and ECD calculations. The structure of illibrefunone A (1) was confirmed by single-crystal X-ray diffraction analysis. All compounds were evaluated in terms of their anti-inflammatory potential on nitric oxide (NO) generation in lipopolysaccharide-stimulated murine RAW264.7 macrophages and murine BV2 microglial cells, antiviral activity against Coxsackievirus B3 (CVB3) and influenza virus A/Hanfang/359/95 (H3N2). Compounds 3 and 4 exhibited potent inhibitory effects on the production of NO in RAW 264.7 cells with IC50 values of 20.57 and 12.87 µM respectively, which were greater than those of dexamethasone (positive control). Compounds 1 and 4-6 exhibited weak activity against Coxsackievirus B3, with IC50 values ranging from 25.87 to 33.33 µM.


Asunto(s)
Antivirales , Illicium , Subtipo H3N2 del Virus de la Influenza A , Óxido Nítrico , Raíces de Plantas , Animales , Ratones , Raíces de Plantas/química , Óxido Nítrico/biosíntesis , Óxido Nítrico/antagonistas & inhibidores , Estructura Molecular , Antivirales/farmacología , Antivirales/química , Antivirales/aislamiento & purificación , Células RAW 264.7 , Illicium/química , Subtipo H3N2 del Virus de la Influenza A/efectos de los fármacos , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Macrófagos/efectos de los fármacos , Enterovirus Humano B/efectos de los fármacos , Lipopolisacáridos/farmacología , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Prenilación
7.
ChemSusChem ; 17(18): e202400221, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-38656613

RESUMEN

Alkali and alkaline earth metal amides are a type of functional materials for hydrogen storage, thermal energy storage, ion conduction, and chemical transformations such as ammonia synthesis and decomposition. The thermal chemistry of lithium amide (LiNH2), as a simple but representative alkali or alkaline earth metal amide, has been well studied previously encouraged by its potentials in hydrogen storage. In comparison, little is known about the interaction of plasma and LiNH2. Herein, we report that the plasma treatment of LiNH2 in an Ar flow under ambient temperature and pressure gives rise to distinctly different reaction products and reaction pathway from that of the thermal process. We found that plasma treatment of LiNH2 leads to the formation of Li colloids, N2, and H2 as observed by UV-vis absorption, EPR, and gas products analysis. Inspired by this very unique interaction between plasma and LiNH2, a chemical loop for ammonia decomposition to N2 and H2 mediated by LiNH2 was proposed and demonstrated.

8.
Artículo en Chino | MEDLINE | ID: mdl-38686486

RESUMEN

Trichoblastoma(TB) is a rare germ cell skin adnexal tumor of the hair, and it is a rare follicular tumor of the skin that differentiates from the hair germ epithelium and is often regarded as a benign skin tumorHowever, it is poorly confined and has a local infiltrative growth pattern. tb occurs in the head and neck region, especially in the face, and presents clinically as a slow growing, well-defined and elevated nodule. TB is routinely treated surgically. Due to the lack of universally accepted treatment guidelines or protocols, the recurrence rate after surgery is high, which makes clinical cure more difficult. In this study, a 65-year-old female patient was found to have a swelling with recurrent rupture and pus flow from the right external auditory canal opening and the auricular cavity. After initial misdiagnosis as otitis externa, she was treated with conventional anti-infective therapy, but her symptoms did not resolve and gradually worsened before coming to our hospital. The condition presented in this case is relativelyrare,therepre,timely and accurate diagnosis and treatment are crucial for prognosis improvement of such diseases.


Asunto(s)
Neoplasias Cutáneas , Humanos , Femenino , Anciano , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/diagnóstico , Neoplasias del Oído/patología , Neoplasias de Anexos y Apéndices de Piel/patología , Neoplasias de Anexos y Apéndices de Piel/diagnóstico , Conducto Auditivo Externo/patología
9.
Molecules ; 29(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38474552

RESUMEN

Bitespiramycin, has been shown to have a therapeutic effect against respiratory tract inflammation, including a potential effect against COVID-19. A current clinical trial in China showed that bitespiramycin was an effective treatment for severe pneumonia and intracranial infection. However, there is lack of an analytical method to elucidate the distribution of bitespiramycin. In this study, a highly sensitive, rapid and reliable UPLC-MS/MS method was developed to comprehensively characterize the bitespiramycin distribution in various bio-samples, which is significantly improved upon the published work. A rapid sample preparation method was developed by using n-butanol as the solvent to extract bitespiramycin from different bio-samples. The extract was then directly analyzed by UPLC-MS/MS coupled with an alkaline-resistant column after centrifugation which avoids the time-consuming concentration process under nitrogen and redissolution. The method was employed to accurately quantify bitespiramycin and its metabolites in rat plasma, tissues, and human cerebrospinal fluid. Notably, the presence of bitespiramycin and its metabolites was identified for the first time in various rat organs including brain, testis, bladder and prostate as well as in human cerebrospinal fluid. This newly developed approach shows great promise for drug distribution assays including other antibiotics and can help elucidate the ADME of bitespiramycin.


Asunto(s)
Cromatografía Líquida con Espectrometría de Masas , Espiramicina/análogos & derivados , Masculino , Ratas , Humanos , Animales , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos
10.
Sci Total Environ ; 923: 171465, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38453086

RESUMEN

Dissolved organic matter (DOM) is one of the most important fluxes in the global carbon cycle but its response to light exposure remains unclear at a molecular-level. The chemical response of DOM to light should vary with its molecular composition and environmental conditions while some basic hypotheses are still unclear, such as the balance between photobleaching and photo-humification and the question of oxidative properties. Here we exposed aquatic DOM from diverse freshwaters impacted by different levels of anthropogenic activity and algal exudates to environmentally-realistic light conditions. We found that photobleaching occurred in DOM with relatively high initial humic content producing low H/C molecules, whereas DOM with low initial humic content was humified. DOM pools with relatively high initial saturation and low aromaticity were prone to transform towards more unsaturated molecular formulae and high H/C molecules with a distinct decrease of bioavailability. Photo-transformation was mainly influenced by reactive intermediates, with reactive oxygen species (ROS) playing a dominant role in humification when the initial humus content of DOM was high. In contrast, for algal DOM with high protein content, it was likely that the autoxidation of excited state DOM was more important than indirect oxidation involving ROS. Our results reveal how photo-transformation patterns depend on the initial composition of DOM and provide new insights into the role of photochemical processes in biogeochemical cycling of DOM.

11.
Nat Chem ; 16(3): 373-379, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38228852

RESUMEN

Photon-driven chemical processes are usually mediated by oxides, nitrides and sulfides whose photo-conversion efficiency is limited by charge carrier recombination. Here we show that lithium hydride undergoes photolysis upon ultraviolet illumination to yield long-lived photon-generated electrons residing in hydrogen vacancies, known as F centres. We demonstrate that photon-driven dehydrogenation and dark rehydrogenation over lithium hydride can be fulfilled reversibly at room temperature, which is about 600 K lower than the corresponding thermal process. As light-driven F centre generation could provide an alternative approach to charge carrier separation to favour chemical transformations that are kinetically or thermodynamically challenging, we show that light-activated lithium hydride cleaves the N≡N triple bond to form a N-H bond under mild conditions. Co-feeding a N2/H2 mixture with low H2 partial pressure leads to photocatalytic ammonia formation at near ambient conditions. This work provides insights into the development of advanced materials and processes for light harvesting and conversion.

12.
J Asian Nat Prod Res ; 26(2): 204-213, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38213077

RESUMEN

Three new cadinane sesquiterpenes (1-3) and three known sesquiterpenes were isolated from the stems and branches of Illicium ternstroemioides A. C. Smith. The structures of the new compounds were elucidated by extensive analysis of spectroscopic and HRESIMS data. The structures of illiternins A-C (1-3) were confirmed by single crystal X-ray diffraction, allowing for the determination of their absolute configurations. Compounds 3 and 6 exhibited antiviral activity against Coxsackievirus B3 with IC50 values of 33.3 and 57.7 µM, respectively.


Asunto(s)
Illicium , Sesquiterpenos , Illicium/química , Estructura Molecular , Sesquiterpenos Policíclicos , Sesquiterpenos/química
13.
J Asian Nat Prod Res ; 26(4): 452-464, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37655543

RESUMEN

Six previously undescribed prenylated C6-C3 derivatives (1-6) were isolated from the root of Illicium ternstroemioides A. C. Smith. Their structures were elucidated based on extensive spectroscopic analyses (UV, IR, 1D and 2D NMR, and HRESIMS). The absolute configurations of 1-3 were determined using electronic circular dichroism (ECD), and Mo2(OAc)4 induced circular dichroism (ICD). Compound 3 exhibited weak activity against Coxsackievirus B3 with an IC50 value of 33.3 µM, and compound 5 exhibited more potent activity against Coxsackievirus B3 with an IC50 value of 6.4 µM.


Asunto(s)
Illicium , Illicium/química , Estructura Molecular , Espectroscopía de Resonancia Magnética , Dicroismo Circular , Antivirales/farmacología
14.
Biochem Genet ; 62(1): 468-484, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37378701

RESUMEN

Family history of hypertension, smoking, diabetes and alcohol consumption and atherosclerotic plaque were identified as common risk factors in IS. We aimed at investigating the relationship between Thymidylate Synthase (TS) gene polymorphisms and ischemic stroke (IS).This case-control research selected and genotyped three single nucleotide polymorphisms (SNPs)of TS( rs699517, rs2790, and rs151264360) with Sanger sequencing in Chinese Han population. We also adopted logistic regression analysis in genetic models for calculating odds ratios and 95% confidence intervals. Genotype-Tissue Expression(GTEx) database analyzed the tissue-specific expression and TS polymorphisms. The ischemic stroke patients showed higher low-density lipoprotein cholesterol and total homocysteine (tHcy). It was found that patients with the TT genotype of rs699517 and GG genotype of rs2790 had larger degrees of tHcy than those with CC + CT genotypes and AA + AG genotypes, respectively. The genotype distribution of the three SNPs did not deviate from Hardy-Weinberg equilibrium (HWE). Haplotype analysis showed that T-G-del was the major haplotype in IS, and C-A-ins was the major haplotype in controls. GTEx database indicated that the rs699517 and rs2790 increased the expression of TS in healthy human and associated with TS expression level in a single tissue. In conclusion: This study has shown that TS rs699517 and rs2790 were significantly related to ischemic stroke patients.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Timidilato Sintasa/genética , Accidente Cerebrovascular Isquémico/genética , Accidente Cerebrovascular Isquémico/complicaciones , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/complicaciones , Polimorfismo de Nucleótido Simple , Genotipo , China , Predisposición Genética a la Enfermedad , Estudios de Casos y Controles , Frecuencia de los Genes
15.
Res Sq ; 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-38045390

RESUMEN

The combinatorial effect of genetic variants is often assumed to be additive. Although genetic variation can clearly interact non-additively, methods to uncover epistatic relationships remain in their infancy. We develop low-signal signed iterative random forests to elucidate the complex genetic architecture of cardiac hypertrophy. We derive deep learning-based estimates of left ventricular mass from the cardiac MRI scans of 29,661 individuals enrolled in the UK Biobank. We report epistatic genetic variation including variants close to CCDC141, IGF1R, TTN, and TNKS. Several loci not prioritized by univariate genome-wide association analysis are identified. Functional genomic and integrative enrichment analyses reveal a complex gene regulatory network in which genes mapped from these loci share biological processes and myogenic regulatory factors. Through a network analysis of transcriptomic data from 313 explanted human hearts, we show that these interactions are preserved at the level of the cardiac transcriptome. We assess causality of epistatic effects via RNA silencing of gene-gene interactions in human induced pluripotent stem cell-derived cardiomyocytes. Finally, single-cell morphology analysis using a novel high-throughput microfluidic system shows that cardiomyocyte hypertrophy is non-additively modifiable by specific pairwise interactions between CCDC141 and both TTN and IGF1R. Our results expand the scope of genetic regulation of cardiac structure to epistasis.

16.
medRxiv ; 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37987017

RESUMEN

The combinatorial effect of genetic variants is often assumed to be additive. Although genetic variation can clearly interact non-additively, methods to uncover epistatic relationships remain in their infancy. We develop low-signal signed iterative random forests to elucidate the complex genetic architecture of cardiac hypertrophy. We derive deep learning-based estimates of left ventricular mass from the cardiac MRI scans of 29,661 individuals enrolled in the UK Biobank. We report epistatic genetic variation including variants close to CCDC141, IGF1R, TTN, and TNKS. Several loci not prioritized by univariate genome-wide association analysis are identified. Functional genomic and integrative enrichment analyses reveal a complex gene regulatory network in which genes mapped from these loci share biological processes and myogenic regulatory factors. Through a network analysis of transcriptomic data from 313 explanted human hearts, we show that these interactions are preserved at the level of the cardiac transcriptome. We assess causality of epistatic effects via RNA silencing of gene-gene interactions in human induced pluripotent stem cell-derived cardiomyocytes. Finally, single-cell morphology analysis using a novel high-throughput microfluidic system shows that cardiomyocyte hypertrophy is non-additively modifiable by specific pairwise interactions between CCDC141 and both TTN and IGF1R. Our results expand the scope of genetic regulation of cardiac structure to epistasis.

17.
Huan Jing Ke Xue ; 44(11): 6297-6308, 2023 Nov 08.
Artículo en Chino | MEDLINE | ID: mdl-37973112

RESUMEN

To investigate the influence of heavy metals in smelting waste residue on the quality of soil and groundwater, a simulation column experiment was conducted to study the migration characteristics of heavy metals from the leaching solution of zinc volatilizing kiln residue in the site soil profile under continuous or intermittent leaching for 90 days. The concentrations of Cd, Cu, Pb, and Zn in leachate and their accumulation, chemical fractions, and particle size distribution characteristics in the soil profile were analyzed, and the retention mechanism of heavy metals was also discussed. The results showed that the concentration of heavy metals in the soil column leachate decreased rapidly after reaching the peak at the earlier leaching stage, and the Cd concentration far exceeded the threshold limit of 0.1 mg·L-1(class Ⅳ) of the Quality Standard for Groundwater(GB/T 14848-2017), indicating that there was Cd pollution risk of groundwater. The soil profile had a great adsorption capacity for heavy metals in the waste residue. Cd, Cu, Pb, and Zn were predominately accumulated in the shallow soil depth(0-10 cm), which was 237-429, 1.25-16.2, 1.38-2.31, and 1.79-3.17 times of the content of corresponding heavy metals in the soil profile before leaching, respectively. The migration distance of heavy metals in the slag under continuous leaching was longer than that under intermittent leaching, and Cd was significantly accumulated in the deep layer of the soil column. The contribution of soil coarse particles(0.5-2.0 mm) to the total cumulative amount of Cd, Cu, and Zn was larger, whereas Pb was more prone to accumulate in the particle size of<0.25 mm. The results of BCR sequential extraction fraction showed that the accumulated Cd, Cu, and Zn in shallow soil depth were mainly present in the weak acid extraction, accounting for 62.4%-76.7%, 72.0%-95.8%, and 67.6%-85.8% of total content, respectively. The X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FTIR) analysis showed that exogenous heavy metals in slag entering the soil would not form a stable mineral phase within 90 days, and the soil hydroxyl(-OH) and carbonyl(C=O) functional groups and iron aluminum silicate oxides were the main retention factors.

18.
Circulation ; 148(21): 1691-1704, 2023 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-37850394

RESUMEN

BACKGROUND: Hypercontractility and arrhythmia are key pathophysiologic features of hypertrophic cardiomyopathy (HCM), the most common inherited heart disease. ß-Adrenergic receptor antagonists (ß-blockers) are the first-line therapy for HCM. However, ß-blockers commonly selected for this disease are often poorly tolerated in patients, where heart-rate reduction and noncardiac effects can lead to reduced cardiac output and fatigue. Mavacamten, myosin ATPase inhibitor recently approved by the US Food and Drug Administration, has demonstrated the ability to ameliorate hypercontractility without lowering heart rate, but its benefits are so far limited to patients with left ventricular (LV) outflow tract obstruction, and its effect on arrhythmia is unknown. METHODS: We screened 21 ß-blockers for their impact on myocyte contractility and evaluated the antiarrhythmic properties of the most promising drug in a ventricular myocyte arrhythmia model. We then examined its in vivo effect on LV function by hemodynamic pressure-volume loop analysis. The efficacy of the drug was tested in vitro and in vivo compared with current therapeutic options (metoprolol, verapamil, and mavacamten) for HCM in an established mouse model of HCM (Myh6R403Q/+ and induced pluripotent stem cell (iPSC)-derived cardiomyocytes from patients with HCM (MYH7R403Q/+). RESULTS: We identified that carvedilol, a ß-blocker not commonly used in HCM, suppresses contractile function and arrhythmia by inhibiting RyR2 (ryanodine receptor type 2). Unlike metoprolol (a ß1-blocker), carvedilol markedly reduced LV contractility through RyR2 inhibition, while maintaining stroke volume through α1-adrenergic receptor inhibition in vivo. Clinically available carvedilol is a racemic mixture, and the R-enantiomer, devoid of ß-blocking effect, retains the ability to inhibit both α1-receptor and RyR2, thereby suppressing contractile function and arrhythmias without lowering heart rate and cardiac output. In Myh6R403Q/+ mice, R-carvedilol normalized hyperdynamic contraction, suppressed arrhythmia, and increased cardiac output better than metoprolol, verapamil, and mavacamten. The ability of R-carvedilol to suppress contractile function was well retained in MYH7R403Q/+ iPSC-derived cardiomyocytes. CONCLUSIONS: R-enantiomer carvedilol attenuates hyperdynamic contraction, suppresses arrhythmia, and at the same time, improves cardiac output without lowering heart rate by dual blockade of α1-adrenergic receptor and RyR2 in mouse and human models of HCM. This combination of therapeutic effects is unique among current therapeutic options for HCM and may particularly benefit patients without LV outflow tract obstruction.


Asunto(s)
Cardiomiopatía Hipertrófica , Metoprolol , Humanos , Ratones , Animales , Carvedilol/farmacología , Carvedilol/uso terapéutico , Metoprolol/uso terapéutico , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Cardiomiopatía Hipertrófica/complicaciones , Cardiomiopatía Hipertrófica/tratamiento farmacológico , Arritmias Cardíacas/tratamiento farmacológico , Arritmias Cardíacas/metabolismo , Antagonistas Adrenérgicos beta/farmacología , Antagonistas Adrenérgicos beta/uso terapéutico , Miocitos Cardíacos/metabolismo , Verapamilo/uso terapéutico , Receptores Adrenérgicos/metabolismo
19.
Phys Chem Chem Phys ; 25(39): 26557-26565, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37753582

RESUMEN

Two-dimensional (2D) heterostructures have been proposed as potential anode materials for lithium-ion batteries due to their large surface areas and excellent electronic properties. In this study, we employ first-principles calculations to investigate the structural stability, electronic properties, and ion diffusion behaviors of 2D graphene/C2N lateral heterostructures. Three species of (5, 26), (11, 26), and (17, 26) heterostructures are chosen to explore the effects of graphene components on electronic properties. The results show that graphene/C2N lateral heterostructures exhibit good dynamic stability due to a small lattice mismatch and strong chemical interaction at the heterojunction interface. By introducing zero-gap graphene, these heterostructures acquire good electronic conductivity with small direct band gaps. The component ratio of graphene can significantly tune the band gap, showing a monotonic decrease as the ratio increases. Moreover, the introduction of C2N components can greatly improve the lithium capacities of heterostructures. Small diffusion energy barriers (0.257-0.273 eV) and a low average operating voltage of 0.758 V are observed in graphene/C2N heterostructures. The effects of graphene components and valence states on Li migration are discussed. Our results demonstrate that the graphene/C2N lateral heterostructure can effectively combine the advantages of graphene and the C2N monolayer, showing great promise as an anode material for lithium-ion batteries.

20.
ChemSusChem ; 16(22): e202300813, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37461801

RESUMEN

Chemical looping ammonia synthesis (CLAS) is a promising alternative route to ammonia production because of its advantages of avoiding competitive adsorption of N2 and hydrogen source (H2 O or H2 ) and intervening the scaling relations in the catalytic process. Our previous studies showed that NH3 can be synthesized at low temperatures via a CLAS mediated by an alkali or alkaline earth metal hydride-imide couple with the aid of transition metal catalysts. Herein, we demonstrate that a group-IIB metal Zn, which has rarely been studied in the thermal-catalytic process, can significantly promote the performance of the lithium hydride-lithium imide (LiH-Li2 NH)-mediated CLAS process (denoted as Zn-LiH-Li2 NH). The addition of Zn dramatically changes the reaction pathway of the LiH-Li2 NH mediated loop by forming a series of intermediates including Li2 NH, lithium zinc intermetallic compounds (LiZnx ), and a ternary metal nitride (LiZnN). LiZnN together with Li2 NH functions as nitrogen carrier in the Zn-LiH-Li2 NH-mediated CLAS. Because of these properties, the kinetics of N2 fixation is significantly enhanced with a reduction in apparent activation energy from 102 kJ mol-1 to 50 kJ mol-1 . The ammonia production rate reaches 956 µmol g-1 h-1 at 350 °C, which is 19 times higher than that of the neat LiH-Li2 NH-mediated CLAS.

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