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1.
J Environ Sci (China) ; 147: 714-725, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39003084

RESUMEN

In this study, an efficient stabilizer material for cadmium (Cd2+) treatment was successfully prepared by simply co-milling olivine with magnesite. Several analytical methods including XRD, TEM, SEM and FTIR, combined with theoretical calculations (DFT), were used to investigate mechanochemical interfacial reaction between two minerals, and the reaction mechanism of Cd removal, with ion exchange between Cd2+ and Mg2+ as the main pathway. A fixation capacity of Cd2+ as high as 270.61 mg/g, much higher than that of the pristine minerals and even the individual/physical mixture of milled olivine and magnesite, has been obtained at optimized conditions, with a neutral pH value of the solution after treatment to allow its direct discharge. The as-proposed Mg-based stabilizer with various advantages such as cost benefits, green feature etc., will boosts the utilization efficiency of natural minerals over the elaborately prepared adsorbents.


Asunto(s)
Cadmio , Compuestos de Hierro , Compuestos de Magnesio , Silicatos , Contaminantes Químicos del Agua , Cadmio/química , Contaminantes Químicos del Agua/química , Compuestos de Magnesio/química , Silicatos/química , Compuestos de Hierro/química , Adsorción , Modelos Químicos , Purificación del Agua/métodos
2.
J Craniofac Surg ; 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39145631

RESUMEN

PURPOSE: The pathophysiology of keloid remains unclear. Exploring the immune heterogeneity and new biomarkers of keloids can help design new therapeutic targets for keloid treatments and prevention. METHODS: The authors performed single-cell RNA sequencing analysis and bulk data differential gene expression analysis of public datasets(GSE92566 and GSE163973). They used Gene Ontology (GO), Gene Set Enrichment Analysis (GSEA), and immune infiltration analysis to identify the function of the differential expressed genes. Besides, the authors performed qt-PCR on keloid tissue and adjacent normal tissues from 3 patients for further verification. RESULTS: M2 macrophage increased in keloid samples than M1 macrophage. The authors identified 2 potential novel biomarkers of keloid, IGF1 and CXCR4, which could inhibit M1 macrophage polarization. The potential mechanism could be inhibiting immune responses and anti-inflammatory activities through INF signaling and E2F targeting. The differential expression of the 2 genes was verified by clinical samples. CONCLUSIONS: The authors identified 2 immune signaling molecules associated with keloid formation (IGF1 and CXCR4) and analyzed their potential pathogenic mechanisms.

3.
Mol Nutr Food Res ; : e2400307, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39091066

RESUMEN

Aging can lead to a series of degenerative changes in skeletal muscle, which would negatively impact physical activity and the quality of life of the elderly. Wolfberry contains numerous bioactive substances. It's vital to further explore the mechanisms underlying its healthy effects on skeletal muscle function during aging progress. This study discusses the benefits and mechanisms of aqueous extract of wolfberry (AEW) to protect skeletal muscle from aging-related persistent DNA damage based on its anti-inflammatory activity. It is found that AEW improves muscle mass, strength, and endurance, modulates the expression of Atrogin-1, MyH, and MuRF-1, and decreases oxidative stress and inflammation levels in aging mice, which is consistent with the in vitro results. Mechanistically, AEW inhibits the pattern recognition receptors (PRRs) pathway induced by inflammatory gene activation, suggesting its potential in response to DNA damage. AEW is also observed to mitigate chromatin decompaction. Network pharmacology is conducted to analyze the potential targets of AEW in promoting DNA repair. In conclusion, the study shows the anti-aging effects of AEW on skeletal muscle by promoting DNA repair and reducing the transcriptional activity of inflammatory factors. AEW intake may become a potential strategy for strengthening skeletal muscle function in the elderly.

4.
Nutr Metab (Lond) ; 21(1): 64, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39118187

RESUMEN

BACKGROUND: Nutrient-rich cheese supplements were demonstrated to have improvements in markers of sarcopenia in healthy elders. However, the potential effects of cheese in individuals with possible sarcopenia remain unknown. METHOD: This 90-day randomized controlled trial (RCT) included 68 women aged 60-80 years with possible sarcopenia in China, who were randomly assigned to three groups: Control group (CG), Original cheese group (OG: 9.0 g protein; 322.8 mg calcium), and Golden cheese group (GG: 12.7 g protein; 802.1 mg calcium). OG and GG were instructed to consume their habitual diet along with 4 slices of supplied cheese, while CG was directed to maintain their usual dietary habits. Face-to-face interviews, anthropometric measurements, and blood sample collection were conducted at baseline, midway (60 days), and the end of the trial. RESULT: At the end of the trial, the primary outcome, changes of Skeletal Muscle Mass Index (SMI) were found to be higher in OG (0.18 ± 0.02 kg/m2) and GG (0.14 ± 0.02 kg/m2) compared to CG (0.09 ± 0.02 kg/m2). The secondary outcome, changes of handgrip strength were higher in GG (1.82 ± 4.16 kg) than CG (-0.61 ± 3.78 kg). There were no significant differences in makers for muscle function between three groups (P > 0.05). In the self-comparison, Creatinine/Cystatin C significantly increased in both OG and GG. In addition, OG had a significant increase in changes of free and total carnitine compared to CG. CONCLUSION: Both golden and original cheese supplementation enhanced muscle strength and mass in older women with possible sarcopenia. The mechanism behind this effect may be linked to muscle cell energy metabolism. TRIAL REGISTRATION: The present study was registered in the Chinese Clinical Trial Registry with the registration number ChiCTR2300078720 (retrospectively registered, 20231215).

5.
J Trop Pediatr ; 70(4)2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39122654

RESUMEN

Cathepsin G (CTSG) plays an important role in the regulation of immune processes. Accumulated studies show that CTSG is involved in the onset and development of type 1 diabetes mellitus (T1DM). As the genetic background of T1DM varies widely among populations, we aimed to study the relationship between genetic polymorphisms in CTSG and T1DM susceptibility in Chinese populations. A total of 141 patients with T1DM and 200 healthy controls were enrolled in the study. Serum CTSG expression was detected using enzyme-linked immunosorbent assay (ELISA). Genotyping of two selected single nucleotide polymorphisms (SNPs) (rs2236742 and rs2070697) of CTSG was performed using PCR and Sanger sequencing. CTSG expression in patients with T1DM was significantly higher than in the control group. Alleles C and T of CTSG SNP rs2236742 were increased in T1DM. No significant associations were found for the SNP rs2070697. Our results indicate that the CTSG rs2236742 allele (C/T) is associated with T1DM in Chinese children and may serve as a new biomarker for predicting T1DM susceptibility.


Asunto(s)
Alelos , Pueblo Asiatico , Diabetes Mellitus Tipo 1 , Predisposición Genética a la Enfermedad , Genotipo , Polimorfismo de Nucleótido Simple , Humanos , Diabetes Mellitus Tipo 1/genética , Femenino , Masculino , Niño , Estudios de Casos y Controles , Pueblo Asiatico/genética , China/epidemiología , Preescolar , Frecuencia de los Genes , Ensayo de Inmunoadsorción Enzimática , Adolescente , Reacción en Cadena de la Polimerasa , Biomarcadores/sangre , Pueblos del Este de Asia
6.
Heliyon ; 10(15): e35415, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39170411

RESUMEN

Background: Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a rare autosomal recessive hereditary disease. Immunoglobulin µ-binding protein 2 (IGHMBP2) gene mutations are the main cause of SMARD1. Case presentation: Here we describe a female infant with SMARD1 carrying heterozygous mutations in IGHMBP2 genes, c.1334A > C(p.His445Pro) and c.1666C > G(p.His556Asp), which were inherited from both parents. Clinical presentations included frequent respiratory infections, respiratory failure, distal limb muscle weakness, and fat pad found at the distal toe. Conclusions: c.1666C > G(p.His556Asp) is a novel site mutation in IGHMBP2. This case expanded knowledge on the genetic profile of SMARD1 and it provides a basis for genetic testing of parents and for genetic counseling to assess the risk of fetal disease.

8.
Cell Biochem Funct ; 42(6): e4107, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39154288

RESUMEN

Despite their diverse physiologies and roles, the heart, skeletal muscles, and smooth muscles all derive from a common embryonic source as bones. Moreover, bone tissue, skeletal and smooth muscles, and the heart share conserved signaling pathways. The maintenance of skeletal health is precisely regulated by osteocytes, osteoblasts, and osteoclasts through coordinated secretion of bone-derived factors known as osteokines. Increasing evidence suggests the involvement of osteokines in regulating atherosclerotic vascular disease. Therefore, this review aims to examine the evidence for the role of osteokines in atherosclerosis development and progression comprehensively. Specifically discussed are extensively studied osteokines in atherosclerosis such as osteocalcin, osteopontin, osteoprotegerin, and fibroblast growth factor 23. Additionally, we highlighted the effects of exercise on modulating these key regulators derived from bone tissue metabolism. We believe that gaining an enhanced understanding of how osteocalcin contributes to the process of atherosclerosis will enable us to develop targeted and comprehensive therapeutic strategies against diseases associated with its progression.


Asunto(s)
Aterosclerosis , Osteocalcina , Humanos , Aterosclerosis/metabolismo , Aterosclerosis/patología , Animales , Osteocalcina/metabolismo , Osteopontina/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Osteoprotegerina/metabolismo , Huesos/metabolismo , Huesos/patología
9.
Int J Biol Macromol ; 277(Pt 3): 134407, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39097062

RESUMEN

The future deployment of biomedicine fields will require a new generation of biodegradable, biocompatible, and non-toxic hydrogels. Alginate and chitosan, naturally occurring polymers, have gained significant interest for hydrogel applications. However, integrating chitosan within alginate-based hydrogels to form microspheres with homogeneous distribution and a tailored surface charge remains challenging. Herein, we report the design and fabrication of homogeneously complexed alginate-chitosan hydrogel microspheres, demonstrating their ability to enhance the viability and liver-specific functionalities of entrapped hepatocytes. By exploring and optimizing the pH and ratio of alginate and chitosan solutions, we achieved well-controlled physicochemical properties, including the degree of sphericity, hydrophilicity, charge property, and surface roughness. Unlike traditional alginate-based hydrogel microspheres, hepatocytes entrapped in homogeneous alginate-chitosan microspheres displayed enhanced viability and liver-specific functions, including albumin secretion, urea synthesis, and cytochrome P-450 enzymatic activity. This work illustrates a potential pathway for manufacturing functionalized microspheres with tunable mechanical properties and functionalities based on biocompatible alginate and chitosan for hepatocyte applications.

10.
Am J Transl Res ; 16(6): 2589-2598, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39006276

RESUMEN

OBJECTIVE: To explore the clinical effectiveness of reconstructing laryngeal function using thyroid cartilage fenestration and "draw-out" resection, supplemented by internal fixation with titanium microplates in early glottic carcinoma. METHODS: Data from 99 patients with glottic carcinoma treated in the Second Affiliated Hospital of Fujian Medical University between January 2014 and September 2021 were retrospectively analyzed. Forty-eight patients who underwent thyroid cartilage fenestration and resection followed by internal fixation with titanium microplates for laryngeal function reconstruction were assigned to the thyroid cartilage fenestration group (TCF group), while the other 51 patients who underwent sternohyoid muscle and fascia repair for laryngeal function reconstruction were assigned to the sternohyoid muscle repair group (SMR group). Patients were followed up for 1-8 years. Data on postoperative phonatory function, respiratory function, swallowing function, and survival status were collected. RESULTS: Compared to the SMR group, patients in the TCF group showed better postoperative recovery in phonatory function and verbal communication (all P<0.05). In the TCF group, patients demonstrated stable respiration and the extubation rate was 100.00%, which was significantly higher than 82.35% in the SMR group (P<0.05). Patients in both groups showed good postoperative recovery of swallowing function (P>0.05). CONCLUSION: One-stage reconstruction of laryngeal function by thyroid cartilage fenestration and "draw-out" resection with adjuvant internal titanium microplate fixation in early glottic carcinoma demonstrates good postoperative recovery and good preservation of the laryngeal function.

11.
Postepy Dermatol Alergol ; 41(3): 314-327, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39027699

RESUMEN

Introduction: One common and very upsetting side effect of burn injuries is scarring, which presents serious difficulties for patients and medical professionals alike. Aim: To assess a new therapeutic approach for treating scars following burn repair procedures in terms of its clinical efficacy. Material and methods: This method administers Hirudoid under ultrasound guidance in addition to fractional CO2 laser treatment. An extensive analysis of the effects of this combination treatment on functional results, patient satisfaction, and scar appearance is being conducted as part of this research. Fractional CO2 laser treatment is utilized for its capacity to stimulate collagen remodelling and decrease scar hypertrophy, while Hirudoid, a topical medicine containing heparinoid, is used to minimize inflammation and enhance tissue healing. Enrolling patients who have had burn repair surgery is the goal of a quasi-experimental study. Conventional scar care methods are performed on the control group, whereas the experimental group is treated with fractional CO2 laser therapy after applying Hirudoid under ultrasound guidance. Throughout the research period, clinical evaluations are carried out on a regular basis. These evaluations cover scar features, pain thresholds, and patient-reported results. Results: The first findings show that the experimental group significantly outperformed the control group in terms of overall look, pigmentation, and scar texture. Functional examinations point to possible improvements in terms of scar flexibility and the range of motion, while patient-reported outcomes show improved satisfaction with the combination therapy. In order to guarantee the combination therapy's viability and tolerance in a clinical context, its side effects and safety profiles are also extensively assessed. In order to improve scar management following burn healing, the study intends to provide important insights into the creation of more patient-friendly and successful therapies. Conclusions: A potential approach to enhancing the clinical results of burn scar treatment is the study of fractional CO2 laser therapy in conjunction with ultrasound-guided Hirudoid. Enhancing scar management tactics via the combination of sophisticated technology and therapy modalities may eventually improve the quality of life for burn injury victims.

12.
Nutrients ; 16(14)2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39064712

RESUMEN

Dietary nutrition plays a crucial role in determining pregnancy outcomes, with poor diet being a major contributor to pregnancy metabolic syndrome and metabolic disorders in offspring. While carbohydrates are essential for fetal development, the excessive consumption of low-quality carbohydrates can increase the risk of pregnancy complications and have lasting negative effects on offspring development. Recent studies not only highlighted the link between carbohydrate intake during pregnancy, maternal health, and offspring well-being, but also suggested that the quality of carbohydrate foods consumed is more critical. This article reviews the impacts of low-carbohydrate and high-carbohydrate diets on pregnancy complications and offspring health, introduces the varied physiological effects of different types of carbohydrate consumption during pregnancy, and emphasizes the importance of both the quantity and quality of carbohydrates in nutritional interventions during pregnancy. These findings may offer valuable insights for guiding dietary interventions during pregnancy and shaping the future development of carbohydrate-rich foods.


Asunto(s)
Carbohidratos de la Dieta , Fenómenos Fisiologicos Nutricionales Maternos , Resultado del Embarazo , Embarazo , Femenino , Humanos , Carbohidratos de la Dieta/administración & dosificación , Complicaciones del Embarazo , Dieta Baja en Carbohidratos
13.
Chin J Nat Med ; 22(7): 663-672, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39059835

RESUMEN

Variations in herb dosage due to species adulteration and dosing inaccuracies can substantially affect clinical safety and efficacy. Accurate species quantification remains challenging, as current methods often yield inconsistent results. This study introduces a novel pyrosequencing-based technique, termed herb molecular quantification (Herb-Q), designed to precisely quantify herbal products. We evaluated its effectiveness using Pinellia ternata and five of its adulterants. Initially, we assessed commonly used DNA barcodes with sequences from a public database, identifying two candidate regions, Maturase K (matK) and internal transcribed spacer 2 (ITS2), for screening specific single nucleotide polymorphism (SNP) loci, allowing for species-specific identification. These loci were validated by amplifying and sequencing genomic material from collected samples. Our validation studies showed that Herb-Q demonstrated excellent linearity, accuracy, repeatability, and detection limits. We established quantitative standard curves with high R2 values (> 0.99) to enable precise species quantification, which were combined with external standards to provide clear and accurate visual quantification results. The average bias in quantifying the tuber of P. ternata was 2.38%, confirming that Herb-Q can accurately identify and quantify herbal product constituents. Moreover, the entire quantification process took less than 4 h. This study presents a novel, rapid method for accurately quantifying species in herbal products and advances the application of DNA barcoding from species identification to quantitative detection.


Asunto(s)
Código de Barras del ADN Taxonómico , Pinellia , Pinellia/genética , Pinellia/química , Código de Barras del ADN Taxonómico/métodos , Polimorfismo de Nucleótido Simple , ADN de Plantas/genética , Análisis de Secuencia de ADN/métodos , Medicamentos Herbarios Chinos/química , Contaminación de Medicamentos , Plantas Medicinales/genética , Plantas Medicinales/química , Plantas Medicinales/clasificación
14.
MycoKeys ; 106: 251-264, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974462

RESUMEN

Two novel species within the family Dictyosporiaceae are described and illustrated from terrestrial habitats on dead culms of bamboo and an unidentified plant, respectively. Through morphological comparisons and the multi-locus phylogenetic analyses of combined LSU, ITS, SSU, and tef1-α sequence dataset, two species, Gregaritheciumbambusicola, Pseudocoleophomaparaphysoidea are identified. Phylogenetically, both species clustered into a monophyletic clade with strong bootstrap support. Gregaritheciumbambusicola sp. nov. can be distinguished from other species within the genus based on its almost straight ascospores. Pseudocoleophomaparaphysoidea sp. nov. differs from other species in its conidiogenous cells intermixed with paraphyses, longer conidiogenous cells and larger conidia. The identification of this lineage contributes to our understanding of the classification of Dictyosporiaceae.

16.
Adv Sci (Weinh) ; 11(31): e2400185, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38896792

RESUMEN

In vitro models coupled with multimodal approaches are needed to dissect the dynamic response of local tumor immune microenvironment (TIME) to immunotherapy. Here the patient-derived primary lung cancer organoids (pLCOs) are generated by isolating tumor cell clusters, including the infiltrated immune cells. A function-associated single-cell RNA sequencing (FascRNA-seq) platform allowing both phenotypic evaluation and scRNA-seq at single-organoid level is developed to dissect the TIME of individual pLCOs. The analysis of 171 individual pLCOs derived from seven patients reveals that pLCOs retain the TIME heterogeneity in the parenchyma of parental tumor tissues, providing models with identical genetic background but various TIME. Linking the scRNA-seq data of individual pLCOs with their responses to anti-PD-1 (αPD-1) immune checkpoint blockade (ICB) allows to confirm the central role of CD8+ T cells in anti-tumor immunity, to identify potential tumor-reactive T cells with a set of 10 genes, and to unravel the factors regulating T cell activity, including CD99 gene. In summary, the study constructs a joint phenotypic and transcriptomic FascRNA-seq platform to dissect the dynamic response of local TIME under ICB treatment, providing a promising approach to evaluate novel immunotherapies and to understand the underlying molecular mechanisms.


Asunto(s)
Neoplasias Pulmonares , Organoides , Microambiente Tumoral , Humanos , Organoides/inmunología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/inmunología , Microambiente Tumoral/inmunología , Microambiente Tumoral/genética , Inmunoterapia/métodos , RNA-Seq/métodos , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Linfocitos T CD8-positivos/inmunología , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Análisis de Expresión Génica de una Sola Célula
17.
Artículo en Inglés | MEDLINE | ID: mdl-38870511

RESUMEN

Objective: This work investigated the clinical intervention effect of evidence-based nursing (EBN) measures for patients in the recovery stage after general anesthesia (GA), aiming to provide a nursing reference for patients in the recovery stage after surgery. Methods: The enrolled participants were 102 patients who underwent surgical treatment in our hospital from December 2021 to December 2022. According to the principle of randomized control, they were enrolled into an observation group (51 cases, Obs group) and a control group (51, cases, Ctrl group), and the general nursing methods and EBN measures were respectively implemented. The incidence of restlessness, complication rate, and nursing satisfaction were compared among patients. The recovery period and visual analog scale (VAS) were evaluated. Results: The eye-opening time, palm-holding time, and extubation time in the Obs group were shorter than those in the Ctrl group (P < .05). The incidence of agitation during convalescence under GA in the Obs group was significantly lower than in the Ctrl group, with a statistically significant difference among both groups (P < .05). Compared to the Ctrl group, the VAS score of patients in the Obs group receiving the EBN was lower at 6 h, 12 h, and 24 h after the surgery (P < .05). The patients in the Obs group presented a substantially lower complication rate and remarkably higher nursing satisfaction (P < .05). Conclusion: The application of EBN measures in patients after GA could effectively shorten the recovery time, lower the incidence of agitation and complication rate during the recovery, and improve nursing satisfaction.

18.
Plant Cell Rep ; 43(7): 167, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38865016

RESUMEN

KEY MESSAGE: 63 L. bicolor WRKY genes were identified and their informatics was analyzed. The results suggested that the LbWRKY genes involved in the development and salt secretion of salt glands in L. bicolor. Salt stress, as a universal abiotic stress, severely inhibits the growth and development of plants. WRKY transcription factors play a vital role in plant growth and development, as well as in response to various stresses. Nevertheless, little is known of systematic genome-wide analysis of the WRKY genes in Limonium bicolor, a model recretohalophyte. In this study, 63 L. bicolor WRKY genes were identified (LbWRKY1-63), which were unevenly distributed across seven chromosomes and one scaffold. Based on the structural and phylogenetic characteristics, 63 LbWRKYs are divided into three main groups. Cis-elements in the LbWRKY promoters were related to growth and development, phytohormone responses, and stress responses. Colinearity analysis showed strong colinearity between LbWRKYs and GmWRKYs from soybean (Glycine max). Therefore, LbWRKY genes maybe have similar functions to GmWRKY genes. Expression analysis showed that 28 LbWRKY genes are highly expressed in roots, 9 in stems, 26 in leaves, and 12 in flowers and most LbWRKY genes responded to NaCl, ABA, and PEG6000. Silencing LbWRKY10 reduced salt gland density and salt secretion ability of leaves, and the salt tolerance of the species. Consistent with this, genes associated with salt gland development were markedly down-regulated in the LbWRKY10-silenced lines. Our findings suggested that the LbWRKY genes involved in the development and salt secretion of salt glands in L. bicolor. Our research provides new insights into the functions of the WRKY family in halophytes.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Filogenia , Proteínas de Plantas , Plumbaginaceae , Tolerancia a la Sal , Plantas Tolerantes a la Sal , Factores de Transcripción , Plumbaginaceae/genética , Plumbaginaceae/fisiología , Plantas Tolerantes a la Sal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Tolerancia a la Sal/genética , Estrés Salino/genética , Estrés Fisiológico/genética , Plantas Modificadas Genéticamente/genética , Regiones Promotoras Genéticas/genética , Genes de Plantas
19.
Molecules ; 29(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38731490

RESUMEN

The zeolite-catalyzed conversion of DME into chemicals is considered environmentally friendly in industry. The periodic density functional theory, statistical thermodynamics, and the transition state theory are used to study some possible parallel reactions about the hydrogen-bonded DME over zeolite ferrierite. The following are the key findings: (1) the charge separation probably leads to the conversion of a hydrogen-bonded DME into a dimethyl oxonium ion (i.e., DMO+ or (CH3)2OH+) with a positive charge of about 0.804 e; (2) the methylation of DME, CH3OH, H2O, and CO by DMO+ at the T2O6 site of zeolite ferrierite shows the different activated internal energy (∆E≠) ranging from 18.47 to 30.06 kcal/mol, implying the strong methylation ability of DMO+; (3) H-abstraction by DMO+ is about 3.94-15.53 or 6.57-18.16 kcal/mol higher than DMO+ methylation in the activation internal energy; (4) six DMO+-mediated reactions are more likely to occur due to the lower barriers, compared to the experimental barrier (i.e., 39.87 kcal/mol) for methyl acetate synthesis; (5) active intermediates, such as (CH3)3O+, (CH3)2OH+, CH3CO+, CH3OH2+, and CH2=OH+, are expected to appear; (6) DMO+ is slightly weaker than the well-known surface methoxy species (ZO-CH3) in methylation; and (7) the methylated activity declines in the order of DME, CH3OH, H2O, and CO, with corresponding rate constants at 463.15 K of about 3.4 × 104, 1.1 × 102, 0.18, and 8.2 × 10-2 s-1, respectively.

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