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1.
Am J Hematol ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38980207

RESUMEN

Patients with steroid-resistant or relapsed immune thrombocytopenia (ITP) suffer increased bleeding risk and impaired quality of life. Baricitinib, an oral Janus-associated kinases (JAK) inhibitor, could alleviate both innate and adaptive immune disorders without inducing thrombocytopenia in several autoimmune diseases. Accordingly, an open-label, single-arm, phase 2 trial (NCT05446831) was initiated to explore the safety and efficacy of baricitinib in ITP. Eligible patients were adults with primary ITP who were refractory to corticosteroids and at least one subsequent treatment, and had platelet counts below 30 × 109/L at enrolment. Participants received baricitinib 4 mg daily for 6 months. The primary endpoint was durable response at the 6-month follow-up. A total of 35 patients were enrolled. Durable response was achieved in 20 patients (57.1%, 95% confidence interval, 39.9 to 74.4), and initial response in 23 (65.7%) patients. For patients responding to baricitinib, the median time to response was 12 (IQR 6-20) days, and the median peak platelet count was 94 (IQR 72-128) × 109/L. Among the 27 patients undergoing extend observation, 12 (44.4%) remained responsive for a median duration of approximately 20 weeks after baricitinib discontinuation. Adverse events were reported in 11 (31.4%) patients, including infections in 6 (17.1%) patients during the treatment period. Treatment discontinuation due to an adverse event was reported in 2 (5.7%) patients. Evidence from this pilot study suggested that baricitinib might be a novel candidate for the armamentarium of ITP-modifying agents. Future studies are warranted to validate the safety, efficacy, and optimal dosing of baricitinib in patients with ITP.

2.
Chem Biodivers ; : e202401210, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39007531

RESUMEN

Four novel Mesona chinensis Benth polysaccharides were isolated using aqueous alcohol precipitation. Their molecular weights were determined using high-performance gel permeation chromatography: MA1 (2.3 kDa), MA2 (80.5 kDa), MA3 (180.9 kDa), and MA4 (635.2 kDa), and their compositions were analyzed using GC-MS. The polysaccharides were mainly D-glucose, D-galactose, L-Rhamnose, D-arabinose, D-xylose, and D-mannose. The structural characteristics were further analyzed using infrared spectrophotometry and were identified as a type of pyrrhic sugar. An insulin-induced insulin resistance model of HepG2 cells and oleic acid-induced fat accumulation model of insulin were established to evaluate the hypolipidemic effects. Three Bacteroides spp. [Bacteroides thetaiotaomicron (BT), B. ovatus (BO), and B. cellulosilyticus (BC)] that were negatively correlated with lipid-lowering activity were used to evaluate the lipid-lowering activity of polysaccharides. The Bacteroides metabolites of MA1 and MA2 exhibited hypolipidemic effects and antioxidant activities and could potentially be used as lipid-lowering supplements.

3.
Front Genet ; 15: 1359829, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38988833

RESUMEN

Objective: Accumulating evidence suggests that patients with ankylosing spondylitis (AS) have an elevated risk for cardiovascular disease (CVD) and cardiovascular death, however, whether AS has causal effects on the risk of CVD is unclear.Two-sample Mendelian randomization (MR) was utilizedto examine the probable causal link between them. Methods: Summary statistics from publicly released genome-wide association studies (GWAS) was used to perform MR analyses. Genetically predicted AS was selected as the exposure variable from published GWAS meta-analyses. CVD was adopted as the outcome variable. The inverse variant weighted method was employed to obtain the casual estimates. The robustness of the results was also examined by evaluating the pleiotropy and heterogeneity of single-nucleotide polymorphisms. Results: According to MR analyses, genetic susceptibility to AS was associated with a high risk of heart failure and ischemic stroke, while negativelygenetic susceptibility was found between AS and peripheral atherosclerosis. No statistical relationship was found between AS and venous thromboembolism, atrial fibrillation, coronary atherosclerosis, and valvular heart disease. Sensitivity analysis showed no evidence of horizontal pleiotropy or heterogeneity. Conclusion: The present study suggests that AS exerts causal effects on the risk of CVD, including heart failure, ischemic stroke, and peripheral atherosclerosis.

4.
Curr Med Sci ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967890

RESUMEN

OBJECTIVE: To examine the clinical phenotype and genetic deficiencies present in Chinese aniridia families with PAX6 haplotype deficiency. METHODS: A comprehensive questionnaire and ophthalmological assessments were administered to both affected patients and unaffected relatives. The clinical feature analysis included the evaluation of visual acuity, intraocular pressure, slit-lamp anterior segment examination, fundus photography, and spectral domain optical coherence tomography. To identify the mutation responsible for aniridia, targeted next-generation sequencing was used as a beneficial technique. RESULTS: A total of 4 mutations were identified, consisting of two novel frameshift mutations (c.314delA, p.K105Sfs*33 and c.838_845dup AACACACC, p.S283Tfs*85), along with two recurring nonsense mutations (c.307C>T, p.R103X and c.619A>T, p.K207*). Complete iris absence, macular foveal hypoplasia, and nystagmus were consistent in these PAX6 haplotype-deficient Chinese aniridia families, while corneal lesions, cataracts, and glaucoma exhibited heterogeneity both among the families and within the same family. CONCLUSION: In our study, two novel PAX6 mutations associated with aniridia were identified in Chinese families, which expanded the phenotypic and genotypic spectrum of PAX6 mutations. We also analyzed the clinical characteristics of PAX6 haplotype deficiency in Chinese aniridia families.

5.
Analyst ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38872436

RESUMEN

To overcome limitations in the generalizability and efficiency of current AAV vectors, in this current study, we constructed an AAV variant library by the insertion of random heptapeptide sequences in the receptor-binding domain of the AAV9 capsid gene. We then applied a recently developed organ-on-a-chip in vitro model of the human blood-brain barrier (BBB) to iteratively enrich for variants that efficiently cross the BBB and transduce astrocyte cells. Through multiple rounds of screening, we obtained two candidate AAV variants, AAV-M6 and AAV-M8, which showed significantly higher BBB penetration efficiency than AAV9 or AAV-PHP.eB. Quantitative PCR (qPCR) assay showed that AAV-M6 could accumulate to a 5 times higher titer, while AAV-M8 reached a 3 times higher titer, than AAV-PHP.eB in the neural chamber of the model. The transduction assay further verified that the AAV-M6 candidate vector was able to infect HA-1800 cells after crossing the BBB, suggesting it could potentially transduce brain parenchymal cells after crossing the hCMEC/D3 layer at higher efficiency than AAV-PHP.eB. Molecular simulations suggested that the human receptor proteins, LY6D and M6PR, could bind the AAV-M6 heptapeptide insertion with high affinity. This study provides two promising candidate AAV vectors and demonstrates the use of this in vitro BBB model for scalable, high-throughput screening of gene therapies. These tools can drive investigations of the mechanisms underlying BBB permeability and the cell-type specificity of virus vectors.

6.
Prev Med ; 185: 108042, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38878800

RESUMEN

OBJECTIVE: We aimed to assess the secular trends in cardiovascular health (CVH) among U.S. adults with different glycemic statuses based on the Life's Essential 8 (LE8). METHODS: This cross-sectional study used nationally representative data from 6 cycles of the National Health and Nutrition Examination Surveys between 2007 and 2018. Survey-weighted linear models were used to assess time trends in LE8 scores. Stratified analyses and sensitivity analyses were conducted to validate the stability of the results. RESULTS: A total of 23,616 participants were included in this study. From 2007 to 2018, there was no significant improvement in overall CVH and the proportion of ideal CVH among participants with diabetes and prediabetes. We observed an opposite trend between health behavior and health factors in the diabetes group, mainly in increasing physical activity scores and sleep scores (P for trend<0.001), and declining BMI scores [difference, -6.81 (95% CI, -12.82 to -0.80)] and blood glucose scores [difference, -6.41 (95% CI, -9.86 to -2.96)]. Dietary health remained at a consistently low level among participants with different glycemic status. The blood lipid scores in the prediabetes group improved but were still at a lower level than other groups. Education/income differences persist in the CVH of participants with diabetes or prediabetes, especially in health behavior factors. Sensitivity analyses of the absolute difference and change in proportion showed a consistent trend. CONCLUSIONS: Trends in CVH among participants with diabetes or prediabetes were suboptimal from 2007 to 2018, with persistent education/income disparities.

7.
Int J Mol Sci ; 25(12)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38928501

RESUMEN

The NDPK gene family is an important group of genes in plants, playing a crucial role in regulating energy metabolism, growth, and differentiation, cell signal transduction, and response to abiotic stress. However, our understanding of the NDPK gene family in Brassica napus L. remains limited. This paper systematically analyzes the NDPK gene family in B. napus, particularly focusing on the evolutionary differences within the species. In this study, sixteen, nine, and eight NDPK genes were identified in B. napus and its diploid ancestors, respectively. These genes are not only homologous but also highly similar in their chromosomal locations. Phylogenetic analysis showed that the identified NDPK proteins were divided into four clades, each containing unique motif sequences, with most NDPKs experiencing a loss of introns/exons during evolution. Collinearity analysis revealed that the NDPK genes underwent whole-genome duplication (WGD) events, resulting in duplicate copies, and most of these duplicate genes were subjected to purifying selection. Cis-acting element analysis identified in the promoters of most NDPK genes elements related to a light response, methyl jasmonate response, and abscisic acid response, especially with an increased number of abscisic acid response elements in B. napus. RNA-Seq results indicated that NDPK genes in B. napus exhibited different expression patterns across various tissues. Further analysis through qRT-PCR revealed that BnNDPK genes responded significantly to stress conditions such as salt, drought, and methyl jasmonate. This study enhances our understanding of the NDPK gene family in B. napus, providing a preliminary theoretical basis for the functional study of NDPK genes and offering some references for further revealing the phenomenon of polyploidization in plants.


Asunto(s)
Brassica napus , Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Filogenia , Proteínas de Plantas , Estrés Fisiológico , Brassica napus/genética , Estrés Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Evolución Molecular , Perfilación de la Expresión Génica , Duplicación de Gen
8.
Ying Yong Sheng Tai Xue Bao ; 35(4): 867-876, 2024 Apr 18.
Artículo en Chino | MEDLINE | ID: mdl-38884221

RESUMEN

To investigate the correlation between carbon and oxygen isotope compositions of plant cellulose and climatic factors as well as plant physiological indices on the southeastern margin of the Qinghai-Tibet Plateau, we examined plant species in eight sampling sites with similar latitudes and different longitudes in this region. Through the characteristics of δ13C and δ18O values, fractionation values (Δ13C and Δ18O) in leaf cellulose, we discussed water use efficiency (WUE) and the environmental factors, the variation of carbon and oxygen isotopes in the southeastern margin of the Qinghai-Tibet Plateau with elevation and longitude, and revealed the indication degrees of isotopic signals to different environments and vegetation physiology. By using the semi-quantitative model of carbon and oxygen dual isotopes, we investigated the physiological adaptation mechanisms of plants to varying environmental conditions. The results demonstrated that both Δ13C and Δ18O of cellulose decreased with increasing elevation and longitude, and Δ13C was more influenced by longitude, while Δ18O was more susceptible to elevation variation. Additionally, Δ13C and Δ18O were significantly and positively correlated with temperature (TEM), precipitation (PRE), potential evapotranspiration (PET), and relative humidity (RH). PRE was the dominant meteorological factor driving the variation of Δ13C, while RH was the dominant meteorological factor influencing Δ18O variation. In contrast to Δ13C, WUE showed a stronger correlation with elevation than with longitude, which increased as elevation and longitude increased. According to the carbon-oxygen model, plant stomatal conductance (gs) and photosynthetic capacity (Amax) decreased with increasing precipitation and relative humidity, while the values increased with increasing elevation and longitude. The combined analysis of carbon and oxygen isotopes of organic matters would yield additional environmental and gas exchange information for studies on climate tracing and vegetation physiology studies on the southeastern margin of the Qinghai-Tibet Plateau.


Asunto(s)
Isótopos de Carbono , Ecosistema , Isótopos de Oxígeno , Isótopos de Oxígeno/análisis , China , Isótopos de Carbono/análisis , Clima , Altitud , Plantas/metabolismo , Plantas/clasificación , Fenómenos Fisiológicos de las Plantas , Tibet , Celulosa/metabolismo , Celulosa/análisis
9.
JAMA Intern Med ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884972
10.
Neuro Oncol ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38864832

RESUMEN

BACKGROUND: Super-enhancers (SEs) typically govern the expression of critical oncogenes and play a fundamental role in the initiation and progression of cancer. Focusing on genes that are abnormally regulated by SE in cancer may be a new strategy for understanding pathogenesis. In the context of this investigation, we have identified a previously unreported SE-driven gene IRF2BP2 in neuroblastoma (NB). METHODS: The expression and prognostic value of IRF2BP2 were detected in public databases and clinical samples. The effect of IRF2BP2 on NB cell growth and apoptosis was evaluated through in vivo and in vitro functional loss experiments. The molecular mechanism of IRF2BP2 was investigated by the study of chromatin regulatory regions and transcriptome sequencing. RESULTS: The sustained high expression of IRF2BP2 results from the activation of a novel SE established by NB master transcription factors MYCN, MEIS2 and HAND2, and they form a new complex that regulates the gene network associated with the proliferation of NB cell populations. We also observed a significant enrichment of the AP-1 family at the binding sites of IRF2BP2. Remarkably, within NB cells, AP-1 plays a pivotal role in shaping the chromatin accessibility landscape, thereby exposing the binding site for IRF2BP2. This orchestrated action enables AP-1 and IRF2BP2 to collaboratively stimulate the expression of the NB susceptibility gene ALK, thereby upholding the highly proliferative phenotype characteristic of NB. CONCLUSION: Our findings indicate that SE-driven IRF2BP2 can bind to AP-1 to maintain the survival of tumor cells via regulating chromatin accessibility of NB susceptibility gene ALK.

11.
Chem Commun (Camb) ; 60(57): 7374-7377, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38922126

RESUMEN

Detailed photophysical processes of two AuCu14 clusters with different substituents (-F or -C(CH3)3) of the thiol ligand were studied in this work. The electronic effect of the substituents led to structural shrinkage, thus enhancing the luminous intensity. The internal conversion (IC) and intersystem crossing (ISC) rates in the AuCu14-C(CH3)3 crystal were slower compared with the AuCu14-F crystal, which was caused by the steric effect.

12.
Metabolism ; 157: 155954, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38878856

RESUMEN

BACKGROUND: Metabolic diseases contribute significantly to premature mortality worldwide, with increasing burdens observed among the working-age population (WAP). This study assessed global, regional, and national trends in metabolic disorders and associated mortality over three decades in WAP. METHODS: Data from the Global Burden of Disease 2019 study were leveraged to assess global metabolism-associated mortality and six key metabolic risk factors in WAP from 1990-2019. An age-period-cohort model was employed to determine the overall percentage change in mortality. RESULTS: The 2019 global metabolic risk-related mortality rate in WAP rose significantly by 50.73%, while the age-standardized mortality rate declined by 21.5%. India, China, Indonesia, the USA, and the Russian Federation were the top contributing countries to mortality in WAP, accounting for 51.01% of the total. High systolic blood pressure (HSBP), high body mass index (HBMI), and high fasting plasma glucose (HFPG) were the top metabolic risk factors for the highest mortality rates. Adverse trends in HBMI-associated mortality were observed, particularly in lower sociodemographic index (SDI) regions. HFPG-related mortality declined globally but increased in older age groups in lower SDI countries. CONCLUSIONS: Despite a general decline in metabolic risk-related deaths in WAP, increasing HBMI- and HFPG-related mortality in lower SDI areas poses ongoing public health challenges. Developing nations should prioritize interventions addressing HBMI and HFPG to mitigate mortality risks in WAP.


Asunto(s)
Carga Global de Enfermedades , Humanos , Persona de Mediana Edad , Adulto , Masculino , Femenino , Factores de Riesgo , Carga Global de Enfermedades/tendencias , Estudios de Cohortes , Enfermedades Metabólicas/mortalidad , Enfermedades Metabólicas/epidemiología , Salud Global , Anciano , Índice de Masa Corporal , Adulto Joven , Factores de Edad , Mortalidad/tendencias
14.
CNS Neurosci Ther ; 30(6): e14779, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38828650

RESUMEN

AIMS: Previous neuroimaging studies of vascular cognitive impairment, no dementia (VCIND), have reported functional alterations, but far less is known about the effects of cognitive training on functional connectivity (FC) of intrinsic connectivity networks (ICNs) and how they relate to intervention-related cognitive improvement. This study provides comprehensive research on the changes in intra- and inter-brain functional networks in patients with VCIND who received computerized cognitive training, with a focus on the underlying mechanisms and potential therapeutic strategies. METHODS: We prospectively collected 60 patients with VCIND who were randomly divided into the training group (N = 30) receiving computerized cognitive training and the control group (N = 30) receiving fixed cognitive training. Functional MRI scans and cognitive assessments were performed at baseline, at the 7-week training, and at the 6-month follow-up. Utilizing templates for ICNs, the study employed a linear mixed model to compare intra- and inter-network FC changes between the two groups. Pearson correlation was applied to calculate the relationship between FC and cognitive function. RESULTS: We found significantly decreased intra-network FC within the default mode network (DMN) following computerized cognitive training at Month 6 (p = 0.034), suggesting a potential loss of functional specialization. Computerized training led to increased functional coupling between the DMN and sensorimotor network (SMN) (p = 0.01) and between the language network (LN) and executive control network (ECN) at Month 6 (p < 0.001), indicating compensatory network adaptations in patients with VCIND. Notably, the intra-LN exhibited enhanced functional specialization after computerized cognitive training (p = 0.049), with significant FC increases among LN regions, which correlated with improvements in neuropsychological measures (p < 0.05), emphasizing the targeted impact of computerized cognitive training on language abilities. CONCLUSIONS: This study provides insights into neuroplasticity and adaptive changes resulting from cognitive training in patients with VCIND, with implications for potential therapeutic strategies.


Asunto(s)
Encéfalo , Disfunción Cognitiva , Imagen por Resonancia Magnética , Red Nerviosa , Humanos , Masculino , Femenino , Anciano , Disfunción Cognitiva/terapia , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/rehabilitación , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Terapia Asistida por Computador/métodos , Estudios Prospectivos , Entrenamiento Cognitivo
15.
Infect Drug Resist ; 17: 2513-2529, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38919832

RESUMEN

Background: Minocycline, a derivative of tetracycline, has anti-Helicobacter pylori (H. pylori) properties and can be used to treat H. pylori infection. However, only a few randomized controlled trials (RCTs) have investigated the efficacy of minocycline-containing quadruple therapy (MCQT) in treating H. pylori infection. This study aimed to determine the efficacy and safety of MCQT and investigate the factors influencing both aspects. Methods: This was a retrospective cohort study. Patients diagnosed with H. pylori infection between January 1, 2022, and July 31, 2023 at. The primary outcome was the eradication rate of H. pylori, and the secondary outcome was the number and type of adverse events. Results: A total of 828 patients were included in this study. The overall H. pylori eradication rate among the included patients at 95% confidence interval (CI) (Range 0.864 to 0.907) was 88.53%. The H. pylori eradication rate for patients who received MCQT regimen as the primary therapy was 92.28% (95% CI: 0.901-0.945), significantly higher than that of patients who received MCQT as rescue therapy (80.81%; 95% CI: 0.761-0.855, P=0.003). Adverse events, including dizziness, abdominal distension, diarrhea, nausea, abdominal discomfort, constipation, headache, rash, sleep disorder, palpitation, backache, and anorexia, occurred in 185 (22.34%) patients, with dizziness being the most common (75/828, 9.06%). Compliance with MCQT therapy was an independent factor influencing H. pylori eradication in patients receiving MCQT as a primary therapy. Compliance and presence or absence of H. pylori infection symptoms at the time of screening were independent factors influencing H. Pylori eradication in patients receiving MCQT as rescue therapy. Factors that influenced the occurrence of adverse events included reasons for H. pylori infection screening, residence, treatment compliance, and the use of acid-suppressant regimens. Conclusion: MCQT regimens were effective in H. pylori infection eradication, and the treatment resulted only in fewer adverse events when used as primary or rescue therapies for H. pylori infection treatment. Future prospective studies with larger sample sizes and more comprehensive data are needed to validate our findings.

16.
Fundam Res ; 4(1): 77-85, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38933830

RESUMEN

The development of stereodivergent synthetic methods to access all four stereoisomers of biologically important α-fluoro γ-butyrolactones containing vicinal stereocenters is of great importance and poses a formidable challenge owing to ring strain and steric hindrance. Herein, a novel asymmetric [3+2] annulation of α-fluoro α-azaaryl acetates with vinylethylene carbonate was successfully developed through Cu/Ir-catalyzed cascade allylic alkylation/lactonization, affording a variety of enantioenriched α-fluoro γ-butyrolactones bearing vicinal stereogenic centers with high reaction efficiency and excellent levels of both stereoselectivity and regioselectivity (up to 98% yield, generally >20:1 dr and >99% ee). Notably, all four stereoisomers of these pharmaceutically valuable molecules could be accessed individually via simple permutations of two enantiomeric catalysts. In addition, other azaaryl acetates bearing α-methyl, α-chlorine or α-phenyl group were tolerated well in this transformation. Reaction mechanistic investigations were conducted to explore the process of this bimetallic catalysis based on the results of reaction intermediates, isotopic labelling experiments, and kinetic studies.

17.
Front Immunol ; 15: 1373876, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38715602

RESUMEN

Objective: The objective of this study was to investigate the impact of electro-acupuncture (EA) on sepsis-related intestinal injury and its relationship with macrophage polarization. Methods: A sepsis model was established using cecal ligation and puncture (CLP) to assess the effectiveness of EA. The extent of pathological injury was evaluated using Chiu's score, the expression of ZO-1 and Ocludin, and the impact on macrophage polarization was examined through flow cytometry and immunofluorescence staining. The expression of spermidine, one type of polyamine, and ornithine decarboxylase (ODC) was measured using ELISA and PCR. Once the efficacy was determined, a polyamine depletion model was created, and the role of polyamines was reassessed by evaluating efficacy and observing macrophage polarization. Results: EA treatment reduced the Chiu's score and increased the expression of ZO-1 and Ocludin in the intestinal tissue of septic mice. It inhibited the secretion of IL-1ß and TNF-α, promoted the polarization of M2-type macrophages, increased the secretion of IL-10, and upregulated the expression of Arg-1, spermidine, and ODC. However, after depleting polyamines, the beneficial effects of EA on alleviating intestinal tissue damage and modulating macrophage polarization disappeared. Conclusion: The mechanism underlying the alleviation of intestinal injury associated with CLP-induced sepsis by EA involves with the promotion of M2-type macrophage polarization mediated by spermidine expression.


Asunto(s)
Modelos Animales de Enfermedad , Electroacupuntura , Macrófagos , Poliaminas , Sepsis , Animales , Sepsis/terapia , Sepsis/metabolismo , Sepsis/inmunología , Ratones , Macrófagos/inmunología , Macrófagos/metabolismo , Electroacupuntura/métodos , Poliaminas/metabolismo , Masculino , Activación de Macrófagos , Intestinos/patología , Intestinos/inmunología , Ratones Endogámicos C57BL , Citocinas/metabolismo
18.
Nat Commun ; 15(1): 3930, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38729939

RESUMEN

Hydrogen-bonded organic frameworks (HOFs) are versatile materials with potential applications in proton conduction. Traditional approaches involve incorporating humidity control to address grain boundary challenges for proton conduction. This study finds vitrification as an alternative strategy to eliminate grain boundary effect in HOFs by rapidly melt quenching the kinetically stable HOF-SXU-8 to glassy state HOF-g. Notably, a remarkable enhancement in proton conductivity without humidity was achieved after vitrification, from 1.31 × 10-7 S cm-1 to 5.62× 10-2 S cm-1 at 100 °C. Long term stability test showed negligible performance degradation, and even at 30 °C, the proton conductivity remained at high level of 1.2 × 10-2 S cm-1. Molecule dynamics (MD) simulations and X-ray total scattering experiments reveal the HOF-g system is consisted of three kinds of clusters, i.e., 1,5-Naphthalenedisulfonic acid (1,5-NSA) anion clusters, N,N-dimethylformamide (DMF) molecule clusters, and H+-H2O clusters. In which, the H+ plays an important role to bridge these clusters and the high conductivity is mainly related to the H+ on H3O+. These findings provide valuable insights for optimizing HOFs, enabling efficient proton conduction, and advancing energy conversion and storage devices.

19.
J Org Chem ; 89(11): 8055-8063, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38809698

RESUMEN

Activated acyl species have proven versatile in the esterification of 2'-OH groups in RNA, enabling structure mapping, caging, profiling, and labeling of the biopolymer. Nearly all reagents developed for this reaction have been achiral; however, a recent study reported that simple chiral amino acid acylimidazole derivatives could yield diastereoselective reactions at RNA 2'-OH in water, enabling up to 4:1 selectivity in screening. Here, we investigated the effect of steric bulk on the stereoselectivity of RNA reaction and on the stability of adducts with a library of 36 chiral acylimidazole scaffolds with increasing steric demand. The results document the highest stereoselectivity yet achieved in RNA acylation reactions, with as high as >99:1 diastereoselectivity at >70% conversion. Also notably, the bulky adducts were found to have markedly improved stability on RNA.


Asunto(s)
Aminoácidos , ARN , Agua , Acilación , Aminoácidos/química , Estereoisomerismo , ARN/química , Agua/química , Estructura Molecular , Imidazoles/química
20.
J Org Chem ; 89(11): 8220-8229, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38752983

RESUMEN

In this work, a practical copper-catalyzed multicomponent coupling reaction of primary aromatic amines, rongalite, and alkynes for the direct synthesis of N-aryl propargylamines has been developed. This method could overcome the substrate limitation in A3 coupling reactions of primary aromatic amines, formaldehyde, and alkynes. Mechanistic studies revealed that rongalite acts as not only the active C1 unit but also the accelerator to activate the in situ-generated N-arylmethanimines for the coupling reaction with alkynes. This coupling reaction is highly efficient and features a broad substrate scope, as well as utility with scale-up synthesis and converting the corresponding product N-aryl propargylamines into useful heterocyclic skeletons.

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