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1.
Blood ; 143(18): 1825-1836, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38211332

RESUMEN

ABSTRACT: Venetoclax, the first-generation inhibitor of the apoptosis regulator B-cell lymphoma 2 (BCL2), disrupts the interaction between BCL2 and proapoptotic proteins, promoting the apoptosis in malignant cells. Venetoclax is the mainstay of therapy for relapsed chronic lymphocytic leukemia and is under investigation in multiple clinical trials for the treatment of various cancers. Although venetoclax treatment can result in high rates of durable remission, relapse has been widely observed, indicating the emergence of drug resistance. The G101V mutation in BCL2 is frequently observed in patients who relapsed treated with venetoclax and sufficient to confer resistance to venetoclax by interfering with compound binding. Therefore, the development of next-generation BCL2 inhibitors to overcome drug resistance is urgently needed. In this study, we discovered that sonrotoclax, a potent and selective BCL2 inhibitor, demonstrates stronger cytotoxic activity in various hematologic cancer cells and more profound tumor growth inhibition in multiple hematologic tumor models than venetoclax. Notably, sonrotoclax effectively inhibits venetoclax-resistant BCL2 variants, such as G101V. The crystal structures of wild-type BCL2/BCL2 G101V in complex with sonrotoclax revealed that sonrotoclax adopts a novel binding mode within the P2 pocket of BCL2 and could explain why sonrotoclax maintains stronger potency than venetoclax against the G101V mutant. In summary, sonrotoclax emerges as a potential second-generation BCL2 inhibitor for the treatment of hematologic malignancies with the potential to overcome BCL2 mutation-induced venetoclax resistance. Sonrotoclax is currently under investigation in multiple clinical trials.


Asunto(s)
Antineoplásicos , Compuestos Bicíclicos Heterocíclicos con Puentes , Resistencia a Antineoplásicos , Neoplasias Hematológicas , Proteínas Proto-Oncogénicas c-bcl-2 , Sulfonamidas , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Sulfonamidas/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Humanos , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Animales , Neoplasias Hematológicas/tratamiento farmacológico , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patología , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Línea Celular Tumoral , Mutación , Apoptosis/efectos de los fármacos
2.
Ann Neurol ; 96(3): 488-507, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38860520

RESUMEN

OBJECTIVE: The role of gamma-aminobutyric acid-ergic (GABAergic) neuron impairment in Alzheimer's disease (AD), and if and how transplantation of healthy GABAergic neurons can improve AD, remain unknown. METHODS: Human-derived medial ganglionic eminence progenitors (hiMGEs) differentiated from programmed induced neural precursor cells (hiNPCs) were injected into the dentate gyrus region of the hippocampus (HIP). RESULTS: We showed that grafts migrate to the whole brain and form functional synaptic connections in amyloid precursor protein gene/ presenilin-1 (APP/PS1) chimeric mice. Following transplantation of hiMGEs, behavioral deficits and AD-related pathology were alleviated and defective neurons were repaired. Notably, exosomes secreted from hiMGEs, which are rich in anti-inflammatory miRNA, inhibited astrocyte activation invitro and in vivo, and the mechanism was related to regulation of CD4+ Th1 cells mediated tumor necrosis factor (TNF) pathway. INTERPRETATION: Taken together, these findings support the hypothesis that hiMGEs transplantation is an alternative treatment for neuronal loss in AD and demonstrate that exosomes with anti-inflammatory activity derived from hiMGEs are important factors for graft survival. ANN NEUROL 2024;96:488-507.


Asunto(s)
Astrocitos , Exosomas , Neuronas GABAérgicas , Células-Madre Neurales , Animales , Exosomas/trasplante , Exosomas/metabolismo , Ratones , Astrocitos/metabolismo , Humanos , Neuronas GABAérgicas/metabolismo , Células-Madre Neurales/trasplante , Células-Madre Neurales/metabolismo , Enfermedad de Alzheimer/metabolismo , Ratones Transgénicos , Cognición/fisiología , Masculino
3.
Mol Psychiatry ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38744992

RESUMEN

High-impact genetic variants associated with neurodevelopmental disorders provide biologically-defined entry points for mechanistic investigation. The 3q29 deletion (3q29Del) is one such variant, conferring a 40-100-fold increased risk for schizophrenia, as well as high risk for autism and intellectual disability. However, the mechanisms leading to neurodevelopmental disability remain largely unknown. Here, we report the first in vivo quantitative neuroimaging study in individuals with 3q29Del (N = 24) and neurotypical controls (N = 1608) using structural MRI. Given prior radiology reports of posterior fossa abnormalities in 3q29Del, we focused our investigation on the cerebellum and its tissue-types and lobules. Additionally, we compared the prevalence of cystic/cyst-like malformations of the posterior fossa between 3q29Del and controls and examined the association between neuroanatomical findings and quantitative traits to probe gene-brain-behavior relationships. 3q29Del participants had smaller cerebellar cortex volumes than controls, before and after correction for intracranial volume (ICV). An anterior-posterior gradient emerged in finer grained lobule-based and voxel-wise analyses. 3q29Del participants also had larger cerebellar white matter volumes than controls following ICV-correction and displayed elevated rates of posterior fossa arachnoid cysts and mega cisterna magna findings independent of cerebellar volume. Cerebellar white matter and subregional gray matter volumes were associated with visual-perception and visual-motor integration skills as well as IQ, while cystic/cyst-like malformations yielded no behavioral link. In summary, we find that abnormal development of cerebellar structures may represent neuroimaging-based biomarkers of cognitive and sensorimotor function in 3q29Del, adding to the growing evidence identifying cerebellar pathology as an intersection point between syndromic and idiopathic forms of neurodevelopmental disabilities.

4.
Nano Lett ; 24(28): 8481-8486, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38976353

RESUMEN

In order to simultaneously accelerate ion and electron transfer in sodium-ion battery (SIB) cathodes, a topotactic superlattice was utilized, in which the atomically intrinsic lattice-matching effect from inner to external surface can boost the charge transfer due to the disappearance of the heterojunction interface. Herein, a topotactic syntopogenous Na3VF6/NaVF3 superlattice formulated as Na2.9V1.1F6 (NVF) was synthesized by a facile one-step low-temperature hydrothermal reaction. NVF nanoparticles show an excellent Na+ storage capacity (∼205 mAh g-1) in a high voltage window up to 4.2 V with ultralong cycling stability. That is associated with the mixed occupancy of V and Na in NVF. The multivalent V centers serve as electron reservoirs to inhibit phase transformation, and the Na-enriched Na3VF6 with better electron conductivity acts as a Na+ reservoir for effective electron transfer. Highly reversible (de)intercalation of Na+ is achieved in the channel of perovskite-type NaVF3 with structural integrity.

5.
Plant Mol Biol ; 114(3): 62, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771394

RESUMEN

Fusarium head blight (FHB) stands out as one of the most devastating wheat diseases and leads to significantly grain yield losses and quality reductions in epidemic years. Exploring quantitative trait loci (QTL) for FHB resistance is a critical step for developing new FHB-resistant varieties. We previously constructed a genetic map of unigenes (UG-Map) according to the physical positions using a set of recombinant-inbred lines (RILs) derived from the cross of 'TN18 × LM6' (TL-RILs). Here, the number of diseased spikelets (NDS) and relative disease index (RDI) for FHB resistance were investigated under four environments using TL-RILs, which were distributed across 13 chromosomes. A number of 36 candidate genes for NDS and RDI from of 19 stable QTLs were identified. The average number of candidate genes per QTL was 1.89, with 14 (73.7%), two (10.5%), and three (15.8%) QTLs including one, two, and 3-10 candidate genes, respectively. Among the 24 candidate genes annotated in the reference genome RefSeq v1.1, the homologous genes of seven candidate genes, including TraesCS4B02G227300 for QNds/Rdi-4BL-4553, TraesCS5B02G303200, TraesCS5B02G303300, TraesCS5B02G303700, TraesCS5B02G303800 and TraesCS5B02G304000 for QNds/Rdi-5BL-9509, and TraesCS7A02G568400 for QNds/Rdi-7AL-14499, were previously reported to be related to FHB resistance in wheat, barely or Brachypodium distachyon. These genes should be closely associated with FHB resistance in wheat. In addition, the homologous genes of five genes, including TraesCS1A02G037600LC for QNds-1AS-2225, TraesCS1D02G017800 and TraesCS1D02G017900 for QNds-1DS-527, TraesCS1D02G018000 for QRdi-1DS-575, and TraesCS4B02G227400 for QNds/Rdi-4BL-4553, were involved in plant defense responses against pathogens. These genes should be likely associated with FHB resistance in wheat.


Asunto(s)
Mapeo Cromosómico , Resistencia a la Enfermedad , Fusarium , Enfermedades de las Plantas , Sitios de Carácter Cuantitativo , Triticum , Triticum/genética , Triticum/microbiología , Sitios de Carácter Cuantitativo/genética , Fusarium/fisiología , Fusarium/patogenicidad , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética , Genes de Plantas , Cromosomas de las Plantas/genética
6.
BMC Plant Biol ; 24(1): 770, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39135170

RESUMEN

BACKGROUND: Unfavorable temperatures significantly constrain the quality formation of Dendrobium officinale, severely limiting its food demand. Salicylic acid (SA) enhances the resistance of D. officinale to stress and possesses various analogs. The impact and mechanism of the SA family on improving the quality of D. officinale under adverse temperature conditions remains unclear. RESULTS: Combined with molecular docking analysis, chlorophyll fluorescence and metabolic analysis after treatments with SA analogues or extreme temperatures are performed in this study. The results demonstrate that both heat and cold treatments impede several main parameters of chlorophyll fluorescence of D. officinale, including the ΦPSII parameter, a sensitive growth indicator. However, this inhibition is mitigated by SA or its chemically similar compounds. Comprehensive branch imaging of ΦPSII values revealed position-dependent improvement of tolerance. Molecular docking analysis using a crystal structure model of NPR4 protein reveals that the therapeutic effects of SA analogs are determined by their binding energy and the contact of certain residues. Metabolome analysis identifies 17 compounds are considered participating in the temperature-related SA signaling pathway. Moreover, several natural SA analogs such as 2-hydroxycinnamic acid, benzamide, 2-(formylamino) benzoic acid and 3-o-methylgallic acid, are further found to have high binding ability to NPR4 protein and probably enhance the tolerance of D. officinale against unfavorable temperatures through flavone and guanosine monophosphate degradation pathways. CONCLUSIONS: These results reveal that the SA family with a high binding capability of NPR4 could improve the tolerance of D. officinale upon extreme temperature challenges. This study also highlights the collaborative role of SA-related natural compounds present in D. officinale in the mechanism of temperature resistance and offers a potential way to develop protective agents for the cultivation of D. officinale.


Asunto(s)
Dendrobium , Simulación del Acoplamiento Molecular , Ácido Salicílico , Dendrobium/metabolismo , Dendrobium/efectos de los fármacos , Ácido Salicílico/metabolismo , Ácido Salicílico/farmacología , Redes y Vías Metabólicas/efectos de los fármacos , Proteínas de Plantas/metabolismo , Temperatura , Clorofila/metabolismo
7.
Plant Biotechnol J ; 22(5): 1282-1298, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38124464

RESUMEN

The repeated emergence of the same trait (convergent evolution) in distinct species is an interesting phenomenon and manifests visibly the power of natural selection. The underlying genetic mechanisms have important implications to understand how the genome evolves under environmental challenges. In cereal crops, both rice and barley can develop black-coloured husk/pericarp due to melanin accumulation. However, it is unclear if this trait shares a common origin. Here, we fine-mapped the barley HvBlp gene controlling the black husk/pericarp trait and confirmed its function by gene silencing. The result was further supported by a yellow husk/pericarp mutant with deletion of the HvBlp gene, derived from gamma ray radiation of the wild-type W1. HvBlp encodes a putative tyrosine transporter homologous to the black husk gene OsBh4 in rice. Surprisingly, synteny and phylogenetic analyses showed that HvBlp and OsBh4 belonged to different lineages resulted from dispersed and tandem duplications, respectively, suggesting that the black husk/pericarp trait has emerged independently. The dispersed duplication (dated at 21.23 MYA) yielding HvBlp occurred exclusively in the common ancestor of Triticeae. HvBlp and OsBh4 displayed converged transcription in husk/pericarp tissues, contributing to the black husk/pericarp trait. Further transcriptome and metabolome data identified critical candidate genes and metabolites related to melanin production in barley. Taken together, our study described a compelling case of convergent evolution resulted from transcriptional convergence after repeated gene duplication, providing valuable genetic insights into phenotypic evolution. The identification of the black husk/pericarp genes in barley also has great potential in breeding for stress-resilient varieties with higher nutritional values.


Asunto(s)
Hordeum , Oryza , Hordeum/genética , Hordeum/metabolismo , Oryza/genética , Oryza/metabolismo , Filogenia , Genes de Plantas , Melaninas/genética , Melaninas/metabolismo , Fitomejoramiento , Sistemas de Transporte de Aminoácidos/genética
8.
J Med Virol ; 96(1): e29380, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38235849

RESUMEN

Hepatic venous pressure gradient (HVPG) is the gold standard for evaluating clinically significant portal hypertension (CSPH). However, reliable noninvasive methods are limited. Our study aims to investigate the diagnostic value of serum Golgi protein 73 (GP73) for CSPH in patients with compensated cirrhosis. The study enrolled 262 consecutive patients with compensated cirrhosis from three centers in China from February 2021 to September 2023, who underwent both serum GP73 tests and HVPG measurements. CSPH was defined as HVPG ≥ 10 mmHg. Diagnostic accuracy was evaluated using the areas under the receiver operating characteristic curve (AUC). The prevalence of CSPH was 56.9% (n = 149). There were significant differences between the CSPH and non-CSPH groups in the median serum GP73 level (126.8 vs. 73.1 ng/mL, p < 0.001). GP73 level showed a significant positive linear correlation with HVPG (r = 0.459, p < 0.001). The AUC for the diagnosis of CSPH using serum GP73 alone was 0.75 (95% confidence interval [CI] 0.68-0.81). Multivariate logistic regression analysis determined that the levels of GP73, platelets and international normalized ratio were independently associated with CSPH. The combination of these three markers was termed "IP73" score with an AUC value of 0.85 (95% CI 0.80-0.89) for CSPH. Using 0 as a cut-off value, the specificity and sensitivity of IP73 score were 77.9% and 81.9%, respectively. The IP73 score offers a novel, simple and noninvasive method of assessing CSPH in patients with compensated cirrhosis. A cut-off value of the IP73 score at 0 can distinguish patients with or without CSPH.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Hipertensión Portal , Humanos , Biomarcadores , Hipertensión Portal/complicaciones , Hipertensión Portal/diagnóstico , Hígado , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Curva ROC , Factores de Tiempo
9.
Plant Cell Environ ; 47(6): 2044-2057, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38392920

RESUMEN

Blue light photoreceptor cryptochrome 1 (CRY1) in herbaceous plants plays crucial roles in various developmental processes, including cotyledon expansion, hypocotyl elongation and anthocyanin biosynthesis. However, the function of CRY1 in perennial trees is unclear. In this study, we identified two ortholog genes of CRY1 (PagCRY1a and PagCRY1b) from Populus, which displayed high sequence similarity to Arabidopsis CRY1. Overexpression of PagCRY1 substantially inhibited plant growth and promoted secondary xylem development in Populus, while CRISPR/Cas9-mediated knockout of PagCRY1 enhanced plant growth and delayed secondary xylem development. Moreover, overexpression of PagCRY1 dramatically increased anthocyanin accumulation. The further analysis supported that PagCRY1 functions specifically in response to blue light. Taken together, our results demonstrated that modulating the expression of blue light photoreceptor CRY1 ortholog gene in Populus could significantly influence plant biomass production and the process of wood formation, laying a foundation for further investigating the light-regulated tree growth.


Asunto(s)
Antocianinas , Criptocromos , Populus , Madera , Antocianinas/biosíntesis , Antocianinas/metabolismo , Luz Azul , Criptocromos/metabolismo , Criptocromos/genética , Regulación de la Expresión Génica de las Plantas , Fotorreceptores de Plantas/metabolismo , Fotorreceptores de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Populus/genética , Populus/metabolismo , Populus/crecimiento & desarrollo , Madera/metabolismo , Madera/crecimiento & desarrollo , Xilema/metabolismo , Xilema/genética , Xilema/crecimiento & desarrollo
10.
Cardiovasc Diabetol ; 23(1): 133, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654269

RESUMEN

BACKGROUND: Metabolic syndrome (MetS) can increase the risk of morbidity and mortality of cardiovascular disease and obstructive coronary artery disease (OCAD), which usually have a poor prognosis. This study aimed to explore the impact of MetS on left ventricular (LV) deformation and function in OCAD patients and investigate the independent factors of impaired LV function and deformation. MATERIALS AND METHODS: A total of 121 patients with OCAD and 52 sex- and age-matched controls who underwent cardiac magnetic resonance scanning were enrolled in the study. All OCAD patients were divided into two groups: OCAD with MetS [OCAD(MetS+), n = 83] and OCAD without MetS [OCAD(MetS-), n = 38]. LV functional and global strain parameters were measured and compared among the three groups. Multivariable linear regression analyses were constructed to investigate the independent factors of LV impairment in OCAD patients. Logistic regression analysis and receiver operating characteristic (ROC) curve analysis were performed to test the prediction efficiency of MetS for LV impairment. RESULTS: From controls to the OCAD(MetS-) group to the OCAD(MetS+) group, LV mass (LVM) increased, and LV global function index (LVGFI) and LV global longitudinal peak strain (GLPS) decreased (all p < 0.05). Compared with the OCAD(MetS-) group, the LV GLPS declined significantly (p = 0.027), the LVM increased (p = 0.006), and the LVGFI decreased (p = 0.043) in the OCAD(MetS+) group. After adjustment for covariates in OCAD patients, MetS was an independent factor of decreased LV GLPS (ß = - 0.211, p = 0.002) and increased LVM (ß = 0.221, p = 0.003). The logistic multivariable regression analysis and ROC analysis showed that combined MetS improved the efficiency of predicting LV GLPS reduction (AUC = 0.88) and LVM (AUC = 0.89) increase. CONCLUSIONS: MetS aggravated the damage of LV deformation and function in OCAD patients and was independently associated with LV deformation and impaired LV strain. Additionally, MetS increased the prediction efficiency of increased LVM and decreased LV GLPS. Early detection and intervention of MetS in patients with OCAD is of great significance.


Asunto(s)
Síndrome Metabólico , Valor Predictivo de las Pruebas , Disfunción Ventricular Izquierda , Función Ventricular Izquierda , Humanos , Masculino , Femenino , Persona de Mediana Edad , Síndrome Metabólico/fisiopatología , Síndrome Metabólico/complicaciones , Síndrome Metabólico/diagnóstico , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología , Anciano , Estudios de Casos y Controles , Medición de Riesgo , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/complicaciones , Imagen por Resonancia Cinemagnética , Factores de Riesgo , Pronóstico , Estenosis Coronaria/fisiopatología , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/complicaciones
11.
Cardiovasc Diabetol ; 23(1): 210, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38902730

RESUMEN

BACKGROUND: Stress hyperglycemia occurs frequently in patients following acute myocardial infarction (AMI) and may aggravate myocardial stiffness, but relevant evidence is still lacking. Accordingly, this study aimed to examine the impact of admission stress hyperglycemia on left ventricular (LV) myocardial deformation in patients following AMI. METHODS: A total of 171 patients with first AMI (96 with normoglycemia and 75 with hyperglycemia) underwent cardiac magnetic resonance (CMR) examination were included. AMI patients were classified according to admission blood glucose level (aBGL): < 7.8 mmol/L (n = 96), 7.8-11.1 mmol/L (n = 41) and ≥ 11.1 mmol/L (n = 34). LV strains, including global radial/circumferential/longitudinal peak strain (PS)/peak systolic strain rate (PSSR)/peak diastolic strain rate (PDSR), were measured and compared between groups. Further, subgroup analyses were separately conducted for AMI patients with and without diabetes. Multivariate analysis was employed to assess the independent association between aBGL and LV global PS in AMI patients. RESULTS: LV global PS, PSSR and PDSR were decreased in radial, circumferential and longitudinal directions in hyperglycemic AMI patients compared with normoglycemic AMI patients (all P < 0.05). These differences were more obvious in patients with diabetes than those without diabetes. AMI patients with aBGL between 7.8 and 11.1 mmol/L demonstrated significant decreased radial and longitudinal PS, radial PSSR, and radial and longitudinal PDSR than those with aBGL < 7.8 mmol/L (all P < 0.05). AMI patients with aBGL ≥ 11.1 mmol/L showed significantly decreased PS, PSSR and PDSR in all three directions than those with aBGL < 7.8 mmol/L, and decreased longitudinal PSSR than those with aBGL between 7.8 and 11.1 (all P < 0.05). Further, aBGL was significantly and independently associated with radial (ß = - 0.166, P = 0.003) and longitudinal (ß = 0.143, P = 0.008) PS. CONCLUSIONS: Hyperglycemia may exacerbate LV myocardial stiffness in patients experienced first AMI, leading to reduction in LV strains. aBGL was an independent indicator of impaired LV global PS in AMI patients. Blood glucose monitoring is more valuable for AMI patients with diabetes.


Asunto(s)
Biomarcadores , Glucemia , Hiperglucemia , Imagen por Resonancia Cinemagnética , Admisión del Paciente , Valor Predictivo de las Pruebas , Función Ventricular Izquierda , Humanos , Masculino , Femenino , Persona de Mediana Edad , Hiperglucemia/fisiopatología , Hiperglucemia/sangre , Hiperglucemia/diagnóstico , Hiperglucemia/complicaciones , Anciano , Glucemia/metabolismo , Biomarcadores/sangre , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/sangre , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/complicaciones , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/sangre , Infarto del Miocardio/diagnóstico , Factores de Riesgo , Estudios Retrospectivos , Fenómenos Biomecánicos
12.
Cardiovasc Diabetol ; 23(1): 148, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38685007

RESUMEN

BACKGROUND: Glycemic control, as measured by glycosylated hemoglobin (HbA1c), is an important biomarker to evaluate diabetes severity and is believed to be associated with heart failure development. Type 2 diabetes mellitus (T2DM) and heart failure with reduced ejection fraction (HFrEF) commonly coexist, and the combination of these two diseases indicates a considerably poorer outcome than either disease alone. Therefore, glycemic control should be carefully managed. The present study aimed to explore the association between glycemic control and clinical outcomes, and to determine the optimal glycemic target in this specific population. METHODS: A total of 262 patients who underwent cardiac MRI were included and were split by HbA1c levels [HbA1c < 6.5% (intensive control), HbA1c 6.5-7.5% (modest control), and HbA1c > 7.5% (poor control)]. The biventricular volume and function, as well as left ventricular (LV) systolic strains in patients in different HbA1c categories, were measured and compared. The primary and secondary outcomes were recorded. The association of different HbA1c levels with adverse outcomes was assessed. RESULTS: Despite similar biventricular ejection fractions, both patients with intensive and poor glycemic control exhibited prominent deterioration of LV systolic strain in the longitudinal component (P = 0.004). After a median follow-up of 35.0 months, 55 patients (21.0%) experienced at least one confirmed endpoint event. Cox multivariable analysis indicated that both patients in the lowest and highest HbA1c categories exhibited a more than 2-fold increase in the risk for primary outcomes [HbA1c < 6.5%: hazard ratio (HR) = 2.42, 95% confidence interval (CI) = 1.07-5.45; P = 0.033; HbA1c > 7.5%: HR = 2.24, 95% CI = 1.01-4.99; P = 0.038] and secondary outcomes (HbA1c < 6.5%: HR = 2.84, 95% CI = 1.16-6.96; P = 0.022; HbA1c > 7.5%: HR = 2.65, 95% CI = 1.08-6.50; P = 0.038) compared with those in the middle HbA1c category. CONCLUSIONS: We showed a U-shaped association of glycemic control with clinical outcomes in patients with T2DM and HFrEF, with the lowest risk of adverse outcomes among patients with modest glycemic control. HbA1c between 6.5% and 7.5% may be served as the optimal hypoglycemic target in this specific population.


Asunto(s)
Biomarcadores , Glucemia , Diabetes Mellitus Tipo 2 , Hemoglobina Glucada , Control Glucémico , Insuficiencia Cardíaca , Valor Predictivo de las Pruebas , Volumen Sistólico , Función Ventricular Izquierda , Remodelación Ventricular , Humanos , Masculino , Femenino , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/diagnóstico por imagen , Hemoglobina Glucada/metabolismo , Persona de Mediana Edad , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/fisiopatología , Anciano , Glucemia/metabolismo , Biomarcadores/sangre , Factores de Riesgo , Estudios Retrospectivos , Imagen por Resonancia Cinemagnética , Factores de Tiempo , Hipoglucemiantes/uso terapéutico , Medición de Riesgo , Pronóstico
13.
Cardiovasc Diabetol ; 23(1): 293, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39118078

RESUMEN

BACKGROUND: The adverse prognostic impact of diabetes on hypertrophic cardiomyopathy (HCM) is poorly understood. We sought to explore the underlying mechanisms in terms of structural and functional remodelling in HCM patients with coexisting diabetes (HCM-DM). METHODS: A total of 45 HCM-DM patients were retrospectively included. Isolated HCM controls (HCM patients without diabetes) were matched to HCM-DM patients in terms of maximal wall thickness, age, and gender distribution. Left ventricular (LV) and atrial (LA) performance were evaluated using cardiac magnetic resonance feature tracking strain analyses. The associations between diabetes and LV/LA impairment were investigated by univariable and multivariable linear regression. RESULTS: Compared with the isolated HCM controls, the HCM-DM patients had smaller end-diastolic volume and stroke volume, lower ejection fraction, larger mass/volume ratio and impaired strains in all three directions (all P < 0.05). In terms of the LA parameters, HCM-DM patients presented impaired LA reservoir and conduit strain/strain rate (all P < 0.05). Among all HCM patients, comorbidity with diabetes was independently associated with a low LV ejection fraction (ß = - 6.05, P < 0.001) and impaired global longitudinal strain (ß = 1.40, P = 0.007). Moreover, compared with the isolated HCM controls, HCM-DM patients presented with more myocardial fibrosis according to late gadolinium enhancement, which was an independent predictor of impaired LV global radial strain (ß = - 45.81, P = 0.008), LV global circumferential strain (ß = 18.25, P = 0.003), LA reservoir strain (ß = - 59.20, P < 0.001) and strain rate (ß = - 2.90, P = 0.002). CONCLUSIONS: Diabetes has adverse effects on LV and LA function in HCM patients, which may be important contributors to severe manifestations and outcomes in those patients. The present study strengthened the evidence of the prevention and management of diabetes in HCM patients.


Asunto(s)
Función del Atrio Izquierdo , Cardiomiopatía Hipertrófica , Diabetes Mellitus , Imagen por Resonancia Cinemagnética , Valor Predictivo de las Pruebas , Volumen Sistólico , Función Ventricular Izquierda , Remodelación Ventricular , Humanos , Masculino , Femenino , Persona de Mediana Edad , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Cardiomiopatía Hipertrófica/fisiopatología , Cardiomiopatía Hipertrófica/complicaciones , Estudios Retrospectivos , Anciano , Diabetes Mellitus/epidemiología , Diabetes Mellitus/fisiopatología , Diabetes Mellitus/diagnóstico , Factores de Riesgo , Adulto , Pronóstico , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología , Comorbilidad , Remodelación Atrial
14.
Cardiovasc Diabetol ; 23(1): 294, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39118075

RESUMEN

BACKGROUND: Patients with concomitant type 2 diabetes mellitus (T2DM) and aortic regurgitation (AR) can present with right ventricular (RV) dysfunction. The current study aimed to evaluate the impact of AR on RV impairment and the importance of ventricular interdependence using cardiac magnetic resonance feature tracking (CMR­FT) in patients with T2DM. METHODS: This study included 229 patients with T2DM (AR-), 88 patients with T2DM (AR+), and 122 healthy controls. The biventricular global radial strain (GRS), global circumferential strain (GCS), and global longitudinal peak strain (GLS) were calculated with CMR­FT and compared among the healthy control, T2DM (AR-), and T2DM (AR+) groups. The RV regional strains at the basal, mid, and apical cavities between the T2DM (AR+) group and subgroups with different AR degrees were compared. Backward stepwise multivariate linear regression analyses were performed to determine the effects of AR and left ventricular (LV) strains on RV strains. RESULTS: The RV GLS, LV GRS, LV GCS, LV GLS, interventricular septal (IVS) GRS and IVS GCS were decreased gradually from the controls through the T2DM (AR-) group to the T2DM (AR+) group. The IVS GLS of the T2DM (AR-) and T2DM (AR+) groups was lower than that of the control group. AR was independently associated with LV GRS, LV GCS, LV GLS, RV GCS, and RV GLS. If AR and LV GLSs were included in the regression analyses, AR and LV GLS were independently associated with RV GLS. CONCLUSION: AR can exacerbate RV dysfunction in patients with T2DM, which may be associated with the superimposed strain injury of the left ventricle and interventricular septum. The RV longitudinal and circumferential strains are important indicators of cardiac injury in T2DM and AR. The unfavorable LV-RV interdependence supports that while focusing on improving LV function, RV dysfunction should be monitored and treated in order to slow the progression of the disease and the onset of adverse outcomes.


Asunto(s)
Insuficiencia de la Válvula Aórtica , Diabetes Mellitus Tipo 2 , Imagen por Resonancia Cinemagnética , Valor Predictivo de las Pruebas , Disfunción Ventricular Derecha , Función Ventricular Izquierda , Función Ventricular Derecha , Humanos , Masculino , Insuficiencia de la Válvula Aórtica/fisiopatología , Insuficiencia de la Válvula Aórtica/diagnóstico por imagen , Femenino , Persona de Mediana Edad , Disfunción Ventricular Derecha/fisiopatología , Disfunción Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/etiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/fisiopatología , Diabetes Mellitus Tipo 2/diagnóstico , Anciano , Estudios Retrospectivos , Adulto , Estudios de Casos y Controles , Factores de Riesgo , Fenómenos Biomecánicos
15.
Cardiovasc Diabetol ; 23(1): 9, 2024 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-38184602

RESUMEN

BACKGROUND: Microvascular pathology is one of the main characteristics of diabetic cardiomyopathy; however, the early longitudinal course of diabetic microvascular dysfunction remains uncertain. This study aimed to investigate the early dynamic changes in left ventricular (LV) microvascular function in diabetic pig model using the cardiac magnetic resonance (CMR)-derived quantitative perfusion technique. METHODS: Twelve pigs with streptozotocin-induced diabetes mellitus (DM) were included in this study, and longitudinal CMR scanning was performed before and 2, 6, 10, and 16 months after diabetic modeling. CMR-derived semiquantitative parameters (upslope, maximal signal intensity, perfusion index, and myocardial perfusion reserve index [MPRI]) and fully quantitative perfusion parameters (myocardial blood flow [MBF] and myocardial perfusion reserve [MPR]) were analyzed to evaluate longitudinal changes in LV myocardial microvascular function. Pearson correlation was used to analyze the relationship between LV structure and function and myocardial perfusion function. RESULTS: With the progression of DM duration, the upslope at rest showed a gradually increasing trend (P = 0.029); however, the upslope at stress and MBF did not change significantly (P > 0.05). Regarding perfusion reserve function, both MPRI and MPR showed a decreasing trend with the progression of disease duration (MPRI, P = 0.001; MPR, P = 0.042), with high consistency (r = 0.551, P < 0.001). Furthermore, LV MPR is moderately associated with LV longitudinal strain (r = - 0.353, P = 0.022), LV remodeling index (r = - 0.312, P = 0.033), fasting blood glucose (r = - 0.313, P = 0.043), and HbA1c (r = - 0.309, P = 0.046). Microscopically, pathological results showed that collagen volume fraction increased gradually, whereas no significant decrease in microvascular density was observed with the progression of DM duration. CONCLUSIONS: Myocardial microvascular reserve function decreased gradually in the early stage of DM, which is related to both structural (but not reduced microvascular density) and functional abnormalities of microvessels, and is associated with increased blood glucose, reduced LV deformation, and myocardial remodeling.


Asunto(s)
Diabetes Mellitus Experimental , Disfunción Ventricular Izquierda , Animales , Porcinos , Glucemia , Corazón , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología , Perfusión
16.
Cardiovasc Diabetol ; 23(1): 90, 2024 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448890

RESUMEN

BACKGROUND: Atrial fibrillation (AF) has been linked to an increased risk of cardiovascular death, overall mortality and heart failure in patients with type 2 diabetes mellitus (T2DM). The present study investigated the additive effects of paroxysmal AF on left ventricular (LV) function and deformation in T2DM patients with or without AF using the cardiovascular magnetic resonance feature tracking (CMR-FT) technique. METHODS: The present study encompassed 225 T2DM patients differentiated by the presence or absence of paroxysmal AF [T2DM(AF+) and T2DM(AF-), respectively], along with 75 age and sex matched controls, all of whom underwent CMR examination. LV function and global strains, including radial, circumferential and longitudinal peak strain (PS), as well as peak systolic and diastolic strain rates (PSSR and PDSR, respectively), were measured and compared among the groups. Multivariable linear regression analysis was used to examine the factors associated with LV global strains in patients with T2DM. RESULTS: The T2DM(AF+) group was the oldest, had the highest LV end­systolic volume index, lowest LV ejection fraction and estimated glomerular filtration rate compared to the control and T2DM(AF-) groups, and presented a shorter diabetes duration and lower HbA1c than the T2DM(AF-) group. LV PS-radial, PS-longitudinal and PDSR-radial declined successively from controls through the T2DM(AF-) group to the T2DM(AF+) group (all p < 0.001). Compared to the control group, LV PS-circumferential, PSSR-radial and PDSR-circumferential were decreased in the T2DM(AF+) group (all p < 0.001) but preserved in the T2DM(AF-) group. Among all clinical indices, AF was independently associated with worsening LV PS-longitudinal (ß = 2.218, p < 0.001), PS-circumferential (ß = 3.948, p < 0.001), PS-radial (ß = - 8.40, p < 0.001), PSSR-radial and -circumferential (ß = - 0.345 and 0.101, p = 0.002 and 0.014, respectively), PDSR-radial and -circumferential (ß = 0.359 and - 0.14, p = 0.022 and 0.003, respectively). CONCLUSIONS: In patients with T2DM, the presence of paroxysmal AF further exacerbates LV function and deformation. Proactive prevention, regular detection and early intervention of AF could potentially benefit T2DM patients.


Asunto(s)
Fibrilación Atrial , Sistema Cardiovascular , Diabetes Mellitus Tipo 2 , Humanos , Fibrilación Atrial/diagnóstico , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Función Ventricular Izquierda , Espectroscopía de Resonancia Magnética
17.
Cardiovasc Diabetol ; 23(1): 28, 2024 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-38218882

RESUMEN

BACKGROUND: Sarcopenia is frequently found in patients with heart failure with reduced ejection fraction (HFrEF) and is associated with reduced exercise capacity, poor quality of life and adverse outcomes. Recent evidence suggests that axial thoracic skeletal muscle size could be used as a surrogate to assess sarcopenia in HFrEF. Since diabetes mellitus (DM) is one of the most common comorbidities with HFrEF, we aimed to explore the potential association of axial thoracic skeletal muscle size with left ventricular (LV) remodeling and determine its prognostic significance in this condition. METHODS: A total of 243 diabetes patients with HFrEF were included in this study. Bilateral axial thoracic skeletal muscle size was obtained using cardiac MRI. Patients were stratified by the tertiles of axial thoracic skeletal muscle index (SMI). LV structural and functional indices, as well as amino-terminal pro-B-type natriuretic peptide (NT-proBNP), were measured. The determinants of elevated NT-proBNP were assessed using linear regression analysis. The associations between thoracic SMI and clinical outcomes were assessed using a multivariable Cox proportional hazards model. RESULTS: Patients in the lowest tertile of thoracic SMI displayed a deterioration in LV systolic strain in three components, together with an increase in LV mass and a heavier burden of myocardial fibrosis (all P < 0.05). Moreover, thoracic SMI (ß = -0.25; P < 0.001), rather than body mass index (ß = -0.04; P = 0.55), was independently associated with the level of NT-proBNP. The median follow-up duration was 33.6 months (IQR, 20.4-52.8 months). Patients with adverse outcomes showed a lower thoracic SMI (40.1 [34.3, 47.9] cm2/m2 vs. 45.3 [37.3, 55.0] cm2/m2; P < 0.05) but a similar BMI (P = 0.76) compared with those without adverse outcomes. A higher thoracic SMI indicated a lower risk of adverse outcomes (hazard ratio: 0.96; 95% confidence interval: 0.92-0.99; P = 0.01). CONCLUSIONS: With respect to diabetes patients with HFrEF, thoracic SMI is a novel alternative for evaluating muscle wasting in sarcopenia that can be obtained by a readily available routine cardiac MRI protocol. A reduction in thoracic skeletal muscle size predicts poor outcomes in the context of DM with HFrEF.


Asunto(s)
Diabetes Mellitus , Insuficiencia Cardíaca , Sarcopenia , Disfunción Ventricular Izquierda , Humanos , Insuficiencia Cardíaca/diagnóstico por imagen , Sarcopenia/diagnóstico por imagen , Sarcopenia/epidemiología , Calidad de Vida , Biomarcadores , Volumen Sistólico/fisiología , Péptido Natriurético Encefálico , Imagen por Resonancia Magnética , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología , Fragmentos de Péptidos , Músculo Esquelético/diagnóstico por imagen , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiología
18.
Cardiovasc Diabetol ; 23(1): 217, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38915040

RESUMEN

BACKGROUND: Diabetic peripheral neuropathy (DPN) is the most prevalent complication of diabetes, and has been demonstrated to be independently associated with cardiovascular events and mortality. This aim of this study was to investigate the subclinical left ventricular (LV) myocardial dysfunction in type 2 diabetes mellitus (T2DM) patients with and without DPN. METHODS: One hundred and thirty T2DM patients without DPN, 61 patients with DPN and 65 age and sex-matched controls who underwent cardiovascular magnetic resonance (CMR) imaging were included, all subjects had no symptoms of heart failure and LV ejection fraction ≥ 50%. LV myocardial non-infarct late gadolinium enhancement (LGE) was determined. LV global strains, including radial, circumferential and longitudinal peak strain (PS) and peak systolic and diastolic strain rates (PSSR and PDSR, respectively), were evaluated using CMR feature tracking and compared among the three groups. Multivariable linear regression analyses were performed to determine the independent factors of reduced LV global myocardial strains in T2DM patients. RESULTS: The prevalence of non-infarct LGE was higher in patients with DPN than those without DPN (37.7% vs. 19.2%, p = 0.008). The LV radial and longitudinal PS (radial: 36.60 ± 7.24% vs. 33.57 ± 7.30% vs. 30.72 ± 8.68%; longitudinal: - 15.03 ± 2.52% vs. - 13.39 ± 2.48% vs. - 11.89 ± 3.02%), as well as longitudinal PDSR [0.89 (0.76, 1.05) 1/s vs. 0.80 (0.71, 0.93) 1/s vs. 0.77 (0.63, 0.87) 1/s] were decreased significantly from controls through T2DM patients without DPN to patients with DPN (all p < 0.001). LV radial and circumferential PDSR, as well as circumferential PS were reduced in both patient groups (all p < 0.05), but were not different between the two groups (all p > 0.05). Radial and longitudinal PSSR were decreased in patients with DPN (p = 0.006 and 0.003, respectively) but preserved in those without DPN (all p > 0.05). Multivariable linear regression analyses adjusting for confounders demonstrated that DPN was independently associated with LV radial and longitudinal PS (ß = - 3.025 and 1.187, p = 0.014 and 0.003, respectively) and PDSR (ß = 0.283 and - 0.086, p = 0.016 and 0.001, respectively), as well as radial PSSR (ß = - 0.266, p = 0.007). CONCLUSIONS: There was more severe subclinical LV dysfunction in T2DM patients complicated with DPN than those without DPN, suggesting further prospective study with more active intervention in this cohort of patients.


Asunto(s)
Enfermedades Asintomáticas , Diabetes Mellitus Tipo 2 , Cardiomiopatías Diabéticas , Neuropatías Diabéticas , Imagen por Resonancia Cinemagnética , Valor Predictivo de las Pruebas , Disfunción Ventricular Izquierda , Función Ventricular Izquierda , Humanos , Masculino , Femenino , Persona de Mediana Edad , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Neuropatías Diabéticas/fisiopatología , Neuropatías Diabéticas/diagnóstico por imagen , Neuropatías Diabéticas/etiología , Neuropatías Diabéticas/diagnóstico , Neuropatías Diabéticas/epidemiología , Anciano , Estudios de Casos y Controles , Cardiomiopatías Diabéticas/fisiopatología , Cardiomiopatías Diabéticas/diagnóstico por imagen , Cardiomiopatías Diabéticas/etiología , Factores de Riesgo , Prevalencia , Estudios Transversales , Volumen Sistólico , Contracción Miocárdica
19.
Cardiovasc Diabetol ; 23(1): 266, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039567

RESUMEN

BACKGROUND: Heart failure with reduced ejection fraction (HFrEF) is associated with a high rate of mortality and morbidity. Evidence has shown that sex differences may be an important contributor to phenotypic heterogeneity in patients with HFrEF. Although diabetes mellitus (DM) frequently coexists with HFrEF and results in a worse prognosis, there remains a need to identify sex-related differences in the characteristics and outcomes of this population. In this study, we aimed to investigate the between-sex differences in clinical profile, left ventricular (LV) remodeling, and cardiovascular risk factors and outcomes in patients with HFrEF concomitant with DM. METHODS: A total of 273 patients with HFrEF concomitant with DM who underwent cardiac MRI were included in this study. Clinical characteristics, LV remodeling as assessed by cardiac MRI, and cardiovascular risk factors and outcomes were compared between sexes. RESULTS: Women were older, leaner and prone to have anemia and hypoproteinemia but less likely to have ischemic etiology. Cardiac MRI revealed that despite similar LVEFs between the sexes, there was more LV concentric remodeling, less impaired global systolic peak strain in longitudinal and circumferential components and a decreased likelihood of late gadolinium enhancement presence in women than in men. During a median follow-up time of 34.6 months, women exhibited better overall survival than men did (log-rank P = 0.042). Multivariable Cox proportional hazards analysis indicated different risk factors for predicting outcomes between sexes, with hypertension [hazard ratio (HR) = 2.05, 95% confidence interval (CI) 1.05 to 4.85, P = 0.041] and hypoproteinemia (HR = 2.27, 95% CI 1.06 to 4.37, P = 0.039) serving as independent determinants of outcomes in women, whereas ischemic etiology (HR = 1.96, 95% CI 1.11 to 3.48, P = 0.021) and atrial fibrillation (HR = 1.86, 95% CI 1.02 to 3.41, P = 0.044) served as independent determinants of outcomes in men. CONCLUSIONS: Among patients with HFrEF concomitant with DM, women displayed different LV remodeling and risk factors and had better survival than men did. Sex-based phenotypic heterogeneity in patients with HFrEF in the context of DM should be addressed in clinical practice.


Asunto(s)
Insuficiencia Cardíaca , Volumen Sistólico , Función Ventricular Izquierda , Remodelación Ventricular , Humanos , Femenino , Masculino , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/diagnóstico , Persona de Mediana Edad , Anciano , Factores Sexuales , Pronóstico , Valor Predictivo de las Pruebas , Disparidades en el Estado de Salud , Factores de Riesgo , Imagen por Resonancia Cinemagnética , Factores de Tiempo , Estudios Retrospectivos , Imagen por Resonancia Magnética , Medición de Riesgo , Diabetes Mellitus/mortalidad , Diabetes Mellitus/fisiopatología , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiología , Factores de Riesgo de Enfermedad Cardiaca
20.
Chemistry ; 30(19): e202303739, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38287793

RESUMEN

To expand the market capacity of p-diethylbenzene (PDEB), core-shell zeolite (TS-1@MCM-48) is designed as a catalyst for PDEB oxidation. TS-1@MCM-48 catalyst is synthesized by in-situ crystallization method and characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), N2 adsorption-desorption, in-situ electron paramagnetic resonance (EPR) and 29Si nuclear magnetic resonance (29Si MAS-NMR). Oxidation of PDEB by H2O2 was investigated systematically in liquid phase. The conversion of PDEB over TS-1@MCM-48 was 28.1 % and the total selectivity was 72.6 %, where the selectivity of EAP (p-ethylacetophenone) and EPEA (4-ethyl-α-methylbenzyl alcohol) was 28.6 % and 44.0 %, respectively. Compared with TS-1 and MCM-48 zeolite, the conversion rate of reactants and the selectivity of products have been significantly improved. The catalytic performance of TS-1@MCM-48 is derived from its well-crystallized microporous core and mesoporous shell with regular channels, which make active sites of TS-1 zeolite in the catalyst be fully utilized and mass transfer resistance be largely reduced. Further through theoretical calculation, we propose that the oxidation of PDEB is the result of the combination and mutual transformation of free radical process and carbocation process. Core-shell structure ensures the conversion rate of raw materials and improves the selectivity of products.

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