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1.
Int J Surg ; 110(8): 5087-5100, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38967517

RESUMEN

BACKGROUND: The optimal surgical approach for intermediate-risk papillary thyroid carcinoma (IR-PTC) (according to ATA definition), whether total thyroidectomy (TT) or lobectomy (LT), has remained a contentious clinical gray area for several decades. This systematic review and meta-analysis aim to provide robust evidence and address this clinical dilemma comprehensively. MATERIALS AND METHODS: A comprehensive literature search was conducted in Pubmed, Embase, Web of Science, and the Cochrane Library from 1st January 2009 to 29th December 2023 to evaluate the impact of different surgical options (TT or LT) on patients with IR-PTC. The primary outcomes included survival, recurrence rates, and postoperative complications. I2 and sensitivity analysis was used to explore the heterogeneity. RESULTS: A total of 8 studies involving 2984 participants were included in this meta-analysis and systematic review. The results indicated that LT was a superior choice for mitigating complications compared to TT [risk ratio (RR), 0.32; 95% CI: 0.24-0.44, P <0.01], particularly for transient complications (RR, 0.24; 95% CI: 0.08-0.65, P <0.01), such as the transient parathyroid dysfunction (RR, 0.04; 95% CI: 0.01-0.15, P <0.01). However, TT did not increase the risk of recurrent laryngeal nerve palsy (RR, 0.78; 95% CI: 0.24-2.47, P =0.67), hemorrhage/seroma (RR, 0.77; 95% CI: 0.48-1.25, P =0.30), and permanent complications (RR, 0.18; 95% CI: 0.02-1.42, P =0.10). Besides, both LT and TT presented similar effect on survival outcomes (overall survival: RR, 1.00; 95% CI: 0.97-1.03, P =0.92, disease-specific survival: RR, 0.99; 95% CI: 0.97-1.02, P =0.69, recurrence-free survival: RR, 1.00; 95% CI: 0.96-1.05, P =0.86), recurrence (RR, 1.05; 95% CI: 0.76-1.46, P =0.76). CONCLUSION: The present meta-analysis revealed that TT did not yield improved outcomes in IR-PTC patients, but was associated with an increased incidence of temporary complications. In light of these findings, it may be advisable to consider LT as the optimal choice for IR-PTC patients.


Asunto(s)
Cáncer Papilar Tiroideo , Neoplasias de la Tiroides , Tiroidectomía , Humanos , Tiroidectomía/métodos , Tiroidectomía/efectos adversos , Cáncer Papilar Tiroideo/cirugía , Cáncer Papilar Tiroideo/mortalidad , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/mortalidad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Recurrencia Local de Neoplasia
2.
Clin Rheumatol ; 43(9): 2919-2926, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38997543

RESUMEN

OBJECTIVE: Diagnosing juvenile idiopathic arthritis (JIA) is challenging. Our study aimed to investigate the clinical significance of anti-α-1,4-D-polygalacturonic acid (PGA) antibodies in JIA, focusing on their role in diagnosis and assessing disease activity. METHODS: In this prospective case-control study, we examined variations in serum levels of PGA-IgA and PGA-IgG among children with different types of JIA and healthy controls. Serum PGA-IgA and PGA-IgG levels were assessed concurrently in children with active and inactive JIA. RESULTS: This study included 126 patients diagnosed with JIA, 13 neonates, and 76 healthy children. Serum PGA-IgA and PGA-IgG levels were assessed, which revealed significant differences in PGA-IgA levels between various JIA subtypes and controls. An analysis of PGA-IgA levels in various JIA states revealed a statistically significant difference. Receiver operating characteristic (ROC) analysis demonstrated the robust predictive capability of PGA-IgA, with an AUC of 0.879 (p < 0.001), along with a specificity of 0.842 and sensitivity of 0.848. CONCLUSION: Increased levels of anti-PGA antibodies, particularly PGA-IgA, were significantly associated with JIA. PGA-IgA may serve as a sensitive biomarker for disease activity in JIA and could potentially aid in the diagnosis of JIA. Key Points • This study found a significant correlation between blood levels of PGA-IgA and juvenile idiopathic arthritis (JIA), which may provide valuable diagnostic insights. • PGA-IgA shows potential as a sensitive biomarker for the assessment of disease activity in JIA patients, helping to determine disease activity.


Asunto(s)
Artritis Juvenil , Biomarcadores , Humanos , Artritis Juvenil/sangre , Artritis Juvenil/inmunología , Artritis Juvenil/diagnóstico , Femenino , Masculino , Biomarcadores/sangre , Niño , Estudios de Casos y Controles , Preescolar , Estudios Prospectivos , Adolescente , Inmunoglobulina G/sangre , Inmunoglobulina A/sangre , Pectinas/inmunología , Curva ROC , Autoanticuerpos/sangre , Lactante , Recién Nacido , Sensibilidad y Especificidad
3.
Gland Surg ; 13(6): 897-909, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39015694

RESUMEN

Background: A subset of patients undergoing thyroid surgery for presumed benign thyroid disease presented with papillary thyroid microcarcinoma (PTMC). A non-invasive and precise method for early recognition of PTMC are urgently needed. The aim of this study was to construct and validate a nomogram that combines intratumoral and peritumoral radiomics features as well as clinical features for predicting PTMC in the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) 3 nodules using ultrasonography. Methods: A retrospective review was conducted on a cohort of 221 patients who presented with ACR TI-RADS 3 nodules. These patients were subsequently pathologically diagnosed with either PTMC or benign thyroid nodules. These patients were randomly divided into a training and test cohort with an 8:2 ratio for developing the clinical model, intratumor-region model, peritumor-region model and the combined-region model respectively. The radiomics features were extracted from ultrasound (US) images of each patient. We employed K-nearest neighbor (KNN) model as the base model for building the radiomics signature and clinical signature. Finally, a radiomics-clinical nomogram that combined intratumoral and peritumoral radiomics features as well as clinical features was developed. The prediction performance of each model was assessed by the area under the curve (AUC), sensitivity, specificity and calibration curve. Results: A total of 23 radiomics features were selected to develop radiomics models. The combined-region radiomics model showed favorable prediction efficiency in both the training dataset (AUC: 0.955) and the test dataset (AUC: 0.923). A radiomics-clinical nomogram was constructed and achieved excellent calibration and discrimination, which yielded an AUC value of 0.950, a sensitivity of 0.950 and a specificity of 0.920. Conclusions: This study proposed the nomogram that contributes to the accurate and intuitive identification of PTMC in ACR TI-RADS 3 nodules.

4.
Adv Mater ; : e2408706, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39016618

RESUMEN

Electrolyte additives are efficient to improve the performance of aqueous zinc-ion batteries (AZIBs), yet the current electrolyte additives are limited to fully water-soluble additives (FWAs) and water-insoluble additives (WIAs). Herein, trace slightly water-soluble additives (SWAs) of zinc acetylacetonate (ZAA) were introduced to aqueous ZnSO4 electrolytes. The SWA system of ZAA is composed of a FWA part and a WIA part in a dynamic manner of dissolution equilibrium. The FWA part exists as soluble small molecules, which efficiently regulate Zn2+ ion solvation structure, while the WIA part exists as insoluble nano-colloids, which in-situ form a thick and robust solid electrolyte interface film on zinc metal anodes (ZMAs). Such small molecular/nano-colloidal multiscale electrolyte additives of ZAA are capable to not only improve ionic conductivity and transference number but also inhibit corrosion, hydrogen evolution, and Zn dendrite on ZMAs. The SWA-based Zn∥Zn half battery delivers a superb cumulative plating capacity of 15 Ah cm-2 under 1 mAh cm-2 and 20 mA cm-2, and the SWA-based NH4V4O10∥Zn pouch cell obtains a capacity retention of 67.8% within 4000 cycles under 4 A g-1. The study provides innovative insights for rational design of electrolyte additives, which may pave the way for the practicality of AZIBs.

5.
Carbohydr Polym ; 339: 122256, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38823922

RESUMEN

Recently, the intestinal lymphatic transport based on Peyer's patches (PPs) is emerging as a promising absorption pathway for natural polysaccharides. Herein, the aim of this study is to investigate the PP-based oral absorption of a pectic polysaccharide from Smilax china L. (SCLP), as well as its uptake and transport mechanisms in related immune cells. Taking advantages of the traceability of fluorescently labeled SCLP, we confirmed that SCLP could be absorbed into PPs and captured by their mononuclear phagocytes (dendritic cells and macrophages) following oral administration. Subsequently, the systematic in vitro study suggested that the endocytic mechanisms of SCLP by model mononuclear phagocytes (BMDCs and RAW264.7 cells) mainly involved caveolae-mediated endocytosis, macropinocytosis and phagocytosis. More importantly, SCLP directly binds and interacts with toll-like receptor 2 (TLR2) and galectin 3 (Gal-3) receptor, and was taken up by mononuclear phagocytes in receptor-mediated manner. After internalization, SCLP was intracellularly transported primarily through endolysosomal pathway and ultimately localized in lysosomes. In summary, this work reveals novel information and perspectives about the in vivo fate of SCLP, which will contribute to further research and utilization of SCLP and other pectic polysaccharides.


Asunto(s)
Ganglios Linfáticos Agregados , Smilax , Animales , Ratones , Células RAW 264.7 , Ganglios Linfáticos Agregados/metabolismo , Smilax/química , Endocitosis , Pectinas/química , Pectinas/metabolismo , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Fagocitosis/efectos de los fármacos , Fagocitos/metabolismo , Fagocitos/efectos de los fármacos , Receptor Toll-Like 2/metabolismo , Ratones Endogámicos BALB C , Masculino , Células Dendríticas/metabolismo , Células Dendríticas/efectos de los fármacos , Administración Oral
6.
Cell Prolif ; : e13692, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38943267

RESUMEN

High-throughput sequencing has sparked increased research interest in RNA modifications, particularly tRNA methylation, and its connection to various diseases. However, the precise mechanisms underpinning the development of these diseases remain largely elusive. This review sheds light on the roles of several tRNA methylations (m1A, m3C, m5C, m1G, m2G, m7G, m5U, and Nm) in diverse biological functions, including metabolic processing, stability, protein interactions, and mitochondrial activities. It further outlines diseases linked to aberrant tRNA modifications, related enzymes, and potential underlying mechanisms. Moreover, disruptions in tRNA regulation and abnormalities in tRNA-derived small RNAs (tsRNAs) contribute to disease pathogenesis, highlighting their potential as biomarkers for disease diagnosis. The review also delves into the exploration of drugs development targeting tRNA methylation enzymes, emphasizing the therapeutic prospects of modulating these processes. Continued research is imperative for a comprehensive comprehension and integration of these molecular mechanisms in disease diagnosis and treatment.

7.
Elife ; 122024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38656297

RESUMEN

Telomeres, which are chromosomal end structures, play a crucial role in maintaining genome stability and integrity in eukaryotes. In the baker's yeast Saccharomyces cerevisiae, the X- and Y'-elements are subtelomeric repetitive sequences found in all 32 and 17 telomeres, respectively. While the Y'-elements serve as a backup for telomere functions in cells lacking telomerase, the function of the X-elements remains unclear. This study utilized the S. cerevisiae strain SY12, which has three chromosomes and six telomeres, to investigate the role of X-elements (as well as Y'-elements) in telomere maintenance. Deletion of Y'-elements (SY12YΔ), X-elements (SY12XYΔ+Y), or both X- and Y'-elements (SY12XYΔ) did not impact the length of the terminal TG1-3 tracks or telomere silencing. However, inactivation of telomerase in SY12YΔ, SY12XYΔ+Y, and SY12XYΔ cells resulted in cellular senescence and the generation of survivors. These survivors either maintained their telomeres through homologous recombination-dependent TG1-3 track elongation or underwent microhomology-mediated intra-chromosomal end-to-end joining. Our findings indicate the non-essential role of subtelomeric X- and Y'-elements in telomere regulation in both telomerase-proficient and telomerase-null cells and suggest that these elements may represent remnants of S. cerevisiae genome evolution. Furthermore, strains with fewer or no subtelomeric elements exhibit more concise telomere structures and offer potential models for future studies in telomere biology.


Asunto(s)
Secuencias Repetitivas de Ácidos Nucleicos , Saccharomyces cerevisiae , Telomerasa , Telómero , Saccharomyces cerevisiae/genética , Telómero/metabolismo , Telómero/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Telomerasa/genética , Telomerasa/metabolismo , Homeostasis del Telómero , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Eliminación de Secuencia
8.
Carbohydr Polym ; 333: 121974, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38494227

RESUMEN

Astragalus membranaceus polysaccharide (APS) possesses excellent immunomodulatory activity. However, there are several studies on the structural characterization of APS. Here, we aimed to elucidate the repeating units of polysaccharides (APS1, 106.5 kDa; APS2, 114.5 kDa) obtained from different Astragalus membranaceus origins and further investigated their immunomodulatory activities. Based on structural analysis, types of the two polysaccharides were identified as arabinogalactan-I (AG-I) and arabinogalactan-II (AG-II), and co-elution of arabinogalactans (AGs) and α-glucan was observed. The backbone of AG-I was 1,4-linked ß-Galp occasionally substituted by α-Araf at O-2 and/or O-3. AG-II was a highly branched polysaccharide with long branches of α-Araf, which were attached to the O-3 of 1,6-linked ß-Galp of the backbone. The presence of AGs in A. membranaceus was confirmed for the first time. The two polysaccharides could promote the expression of IL-6, IL-1ß and TNF-α in RAW264.7 cells via MAPKs and NF-κB signaling pathways. The constants for APS1 and APS2 binding to Toll-like receptor 4 (TLR4) were 1.83 × 10-5 and 2.08 × 10-6, respectively. Notably, APS2 showed better immunomodulatory activity than APS1, possibly because APS2 contained more AGs. Hence, the results suggested that AGs were the vital components of APS in the immunomodulatory effect.


Asunto(s)
Astragalus propinquus , Galactanos , Galactanos/farmacología , Galactanos/química , Polisacáridos/farmacología , Polisacáridos/química , Transducción de Señal
9.
Transl Cancer Res ; 13(1): 278-289, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38410213

RESUMEN

Background: Conventional ultrasound (CUS) technology has proven to be successful in the identification of thyroid nodules. Moreover, the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) was developed for the purpose of evaluating the risk of thyroid nodules based on ultrasound imaging. Nevertheless, identifying papillary thyroid microcarcinoma (PTMC) from TI-RADS 3 nodules using this system can be difficult due to overlapping morphological features. The main objective of this study was to investigate the efficacy of a machine learning model that utilizes ultrasound-based radiomics features and clinical information in accurately predicting the presence of PTMC in TI-RADS 3 nodules. Methods: A total of 221 patients with TI-RADS 3 nodules were included, consisting of 91 cases of PTMC and 130 benign thyroid nodules. They were randomly divided into training and test cohort in an 8:2 ratio. Radiomics features were extracted from CUS images by manually outlining the targets, while clinical parameters were obtained from electronic medical records. The radiomics model, clinical model, and combined model were constructed and validated to distinguish between PTMC and benign thyroid nodules. Radiomics variables were extracted via the Pyradiomics package (V1.3.0). Moreover, least absolute shrinkage and selection operator (LASSO) regression was used for feature selection. Light Gradient Boosting Machine (LightGBM) was employed to build both radiomics and clinical models. Ultimately, a radiomics-clinical model, which fused radiomics features with clinical information, was developed. Results: Among a total of 1,477 radiomics features, fifteen features that were found to be associated with PTMC through univariate analysis and LASSO regression were selected for the development of the radiomics model. The combined "radiomics-clinical" model demonstrated superior diagnostic accuracy compared to the clinical model for distinguishing PTMC in both the training dataset [area under receiver operating curve (AUC): 0.975 vs. 0.845] and the validation dataset (AUC: 0.898 vs. 0.811). We constructed a radiomics-clinical nomogram, and the clinical applicability was confirmed through decision curve analysis. Conclusions: Utilizing an ultrasound-based radiomics approach has proven to be effective in predicting PTMC in patients with TI-RADS 3 nodules.

10.
Carbohydr Polym ; 328: 121745, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38220331

RESUMEN

Angelica sinensis polysaccharide (ASP) possesses diverse bioactivities; however, its metabolic fate following oral administration remains poorly understood. To intuitively determine its intestinal digestion behavior after oral administration, ASP was labeled with fluorescein, and it was found to accumulate and be degraded in the cecum and colon. Therefore, we investigated the in vitro enzymatic degradation behavior and identified the products. The results showed that ASP could be degraded into fragments with molecular weights similar to those of the fragments observed in vivo. Structural characterization revealed that ASP is a highly branched acid heteropolysaccharide with AG type II domains, and its backbone is predominantly composed of 1,3-Galp, →3,6)-Galp-(1→6)-Galp-(1→, 1,4-Manp, 1,4-Rhap, 1,3-Glcp, 1,2,3,4-Galp, 1,3,4,6-Galp, 1,3,4-GalAp and 1,4-GlcAp, with branches of Araf, Glcp and Galp. In addition, the high molecular weight enzymatic degradation products (ASP H) maintained a backbone structure almost identical to that of ASP, but exhibited only partial branch changes. Then, the results of ethanol-induced acute liver injury experiments revealed that ASP and ASP H reduced the expression of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and malondialdehyde (MDA) and increased the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) levels, thereby relieving ethanol-induced acute liver injury.


Asunto(s)
Angelica sinensis , Angelica sinensis/química , Etanol/toxicidad , Etanol/metabolismo , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , Hígado , Estrés Oxidativo
11.
Plant Physiol Biochem ; 207: 108341, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38266557

RESUMEN

Low temperature is one of the most important environmental factors limiting tea plants' geographic distribution and severely affects spring tea's yield and quality. Circadian components contribute to plant responses to low temperatures; however, comparatively little is known about these components in tea plants. In this study, we identified a core clock component the LATE ELONGATED HYPOCOTYL, CsLHY, which is mainly expressed in tea plants' mature leaves, flowers, and roots. Notably, CsLHY maintained its circadian rhythmicity of expression in summer, but was disrupted in winter and held a high expression level. Meanwhile, we found that CsLHY expression rhythm was not affected by different photoperiods but was quickly broken by cold, and the low temperature induced and kept CsLHY expression at a relatively high level. Yeast one-hybrid and dual-luciferase assays confirmed that CsLHY can bind to the promoter of Sugars Will Eventually be Exported Transporters 17 (CsSWEET17) and function as a transcriptional activator. Furthermore, suppression of CsLHY expression in tea leaves not only reduced CsSWEET17 expression but also impaired the freezing tolerance of leaves compared to the control. Our results demonstrate that CsLHY plays a positive role in the low-temperature response of tea plants by regulating CsSWEET17 when considered together.


Asunto(s)
Camellia sinensis , Frío , Factores de Transcripción/metabolismo , Camellia sinensis/metabolismo , Ritmo Circadiano , , Regulación de la Expresión Génica de las Plantas
12.
Nucleic Acids Res ; 52(D1): D1588-D1596, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37933857

RESUMEN

Perennial woody plants hold vital ecological significance, distinguished by their unique traits. While significant progress has been made in their genomic and functional studies, a major challenge persists: the absence of a comprehensive reference platform for collection, integration and in-depth analysis of the vast amount of data. Here, we present PPGR (Resource for Perennial Plant Genomes and Regulation; https://ngdc.cncb.ac.cn/ppgr/) to address this critical gap, by collecting, integrating, analyzing and visualizing genomic, gene regulation and functional data of perennial plants. PPGR currently includes 60 species, 847 million protein-protein/TF (transcription factor)-target interactions, 9016 transcriptome samples under various environmental conditions and genetic backgrounds. Noteworthy is the focus on genes that regulate wood production, seasonal dormancy, terpene biosynthesis and leaf senescence representing a wealth of information derived from experimental data, literature mining, public databases and genomic predictions. Furthermore, PPGR incorporates a range of multi-omics search and analysis tools to facilitate browsing and application of these extensive datasets. PPGR represents a comprehensive and high-quality resource for perennial plants, substantiated by an illustrative case study that demonstrates its capacity in unraveling gene functions and shedding light on potential regulatory processes.


Asunto(s)
Bases de Datos Genéticas , Genoma de Planta , Genómica , Plantas/genética , Transcriptoma
13.
J Hazard Mater ; 464: 133011, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-37988868

RESUMEN

Microwave discharge electrodeless lamp (MDEL) is a novel ultraviolet (UV) light source. Synergistic disinfection using UV light emitted by MDEL (MWUV) coupled with ozone (O3) at an ultra-low dose was investigated. Escherichia coli and Bacillus subtilis were deactivated more effectively by MWUV/O3 than by either MWUV or O3 alone. MWUV/O3 treatment using an O3 concentration of 0.4 mg/L gave an E. coli inactivation rate of 5.52 log. The photoreactivation degree and rate of E. coli were lower after inactivation by MWUV/O3 treatment than after MWUV treatment alone. The maximum photoreactivation rates after the MWUV/O3 and MWUV treatments were 2.90% and 16.08%, respectively. MWUV/O3 disinfection also inhibited dark resurrection of E. coli and gave a maximum dark resurrection rate of 0.0036%. Electron paramagnetic resonance spectroscopy indicated that more hydroxyl radicals were generated during MWUV/O3 treatment. Scanning electron microscopy and laser confocal scanning microscopy observations indicated that O3 played a key role in breaking down the cell structure. MWUV/O3 treatment gave a good disinfection effect on fecal coliform bacteria in actual domestic wastewater. The results indicated that inactivation of bacteria can be more effectively achieved by MWUV treatment with O3.


Asunto(s)
Ozono , Purificación del Agua , Desinfección/métodos , Aguas Residuales , Escherichia coli , Microondas , Rayos Ultravioleta , Purificación del Agua/métodos
14.
Int J Biol Macromol ; 253(Pt 2): 126357, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37595710

RESUMEN

Grifola frondosa polysaccharide (GFP) is mainly composed of α-1,4 glycosidic bonds and possesses multiple pharmacological activities. However, the absence of pharmacokinetic studies has limited its further development and utilization. Herein, GFP was labeled with 5-DTAF (FGFP) and cyanine 5.5 amine (GFP-Cy5.5) to investigate its gastrointestinal metabolism characteristics and mechanism. Significant distributions of the polysaccharide in the liver and kidneys were observed by near infrared imaging. To investigate the specific distribution form of the polysaccharide, in vitro digestion models were constructed and revealed that FGFP was degraded in saliva and rat small intestine extract. The metabolites were detected in the stomach and small intestine, followed by further degradation in the distal intestine in the in vivo experiment. Subsequent investigations showed that α-amylase was involved in the gastrointestinal degradation of GFP, and its metabolite finally entered the kidneys, where it was excreted directly with urine.


Asunto(s)
Grifola , Grifola/química , Polisacáridos/química , Hígado
15.
Int J Biol Macromol ; 242(Pt 1): 124707, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37146861

RESUMEN

As typical acetylated glucomannans, Dendrobium officinale polysaccharides (DOPs) from different origins differ in their structural characteristics and some of their physicochemical properties. To rapidly select D. officinale plants, we systematically investigate the differences among DOPs from different origins and analyzed the structural characteristics, such as the degree of acetylation and monosaccharide composition; the physicochemical properties, such as solubility, water absorption and apparent viscosity; and the lipid-lowering activity of the obtained DOPs. Principal component analysis (PCA), a method for analyzing multiple variables, was used to analyze the relationship between the physicochemical and structural properties, and lipid-lowering activity. It was found that the structural and physicochemical characteristics had significant effects on lipid-lowering activity, and DOPs with a high degree of acetylation, high apparent viscosity and large D-mannose-to-d-glucose ratio were associated with greater lipid-lowering activity. Therefore, this study provides a reference for the selection and application of D. officinale.


Asunto(s)
Dendrobium , Dendrobium/química , Análisis de Componente Principal , Monosacáridos , Polisacáridos/química , Lípidos
16.
Materials (Basel) ; 16(3)2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36770105

RESUMEN

In this study, elastic metamaterial sandwich plates with axially deformed Timoshenko beam cores, considering both the out-of-plane and in-plane deformations of the face plates, are designed and the vibration band-gap properties are explored. The beam cores act as local resonators that can bear axial force, bending moment and shearing force. The finite element method (FEM) and the spectral element method (SEM) are combined to create the finite/spectral element hybrid method (FE-SEHM) for establishing the dynamic model and calculating the frequency response functions (FRFs) of the elastic metamaterial sandwich plate with axially deformed beam cores. It is observed that the metamaterial sandwich plate possesses both the axial and transverse vibration band-gaps of the beams, and the two kinds of band-gaps are independent. Compared with the metamaterial sandwich plates with rod cores, those with axially deformed beam cores have more extensive application ranges for vibration reduction.

17.
Nat Prod Res ; 37(16): 2697-2703, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36214541

RESUMEN

Dendrobium catenatum Lindl. has been long used in China as a functional food and traditional Chinese medicine and polysaccharides from Dendrobium catenatum Lindl. (DOP) exhibited extensive bioactivities. However, studies on the structure-activity relationship of DOP are rarely reported. Here, two polysaccharides named DOP-1 and DOP-2 were obtained, which differed in the ratio of monosaccharide composition and molecular weight. Structural characteristics were elucidated by spectral and chemical analysis. The main structures of DOPs were the linkage of ß-(1→4)-D-Manp, with some attached 2-O- or 3-O-acetylated groups. Additionally, the DPPH, hydroxyl and superoxide radicals scavenging assays of DOP-1 and DOP-2 showed that DOP-2 exhibited the higher antioxidant activity, which might be related to its lower molecular weight, higher mannose proportion and lower degree of acetylation, and higher phenolic content. Our results provide a more accurate basis for the application of DOPs in the pharmaceutical and food industries.

18.
Small ; 19(9): e2206859, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36564350

RESUMEN

Electrocatalytic hydrogen evolution reaction (HER) in alkaline media is important for hydrogen economy but suffers from sluggish reaction kinetics due to a large water dissociation energy barrier. Herein, Pt5 P2 nanocrystals anchoring on amorphous nickel phosphate nanorods as a high-performance interfacial electrocatalyst system (Pt5 P2 NCs/a-NiPi) for the alkaline HER are demonstrated. At the unique polycrystalline/amorphous interface with abundant defects, strong electronic interaction, and optimized intermediate adsorption strength, water dissociation is accelerated over abundant oxophilic Ni sites of amorphous NiPi, while hydride coupling is promoted on the adjacent electron-rich Pt sites of Pt5 P2 . Meanwhile, the ultra-small-sized Pt5 P2 nanocrystals and amorphous NiPi nanorods maximize the density of interfacial active sites for the Volmer-Tafel reaction. Pt5 P2 NCs/a-NiPi exhibits small overpotentials of merely 9 and 41 mV at -10 and -100 mA cm-2 in 1 M KOH, respectively. Notably, Pt5 P2 NCs/a-NiPi exhibits an unprecedentedly high mass activity (MA) of 14.9 mA µgPt -1 at an overpotential of 70 mV, which is 80 times higher than that of Pt/C and represents the highest MA of reported Pt-based electrocatalysts for the alkaline HER. This work demonstrates a phosphorization and interfacing strategy for promoting Pt utilization and in-depth mechanistic insights for the alkaline HER.

19.
Food Funct ; 13(13): 7274-7286, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35726749

RESUMEN

Recently, Dendrobium officinale polysaccharide (DOP), a typical acetylated glucomannan, has been widely applied in functional foods owing to its excellent bioactivity. However, the insufficiency of studies on in vivo process severely limits the further utilization of DOP. The aim of this study was to systematically investigate the gastrointestinal digestive behaviour of DOP after oral administration by labelling it with two fluorescein aminopyrene-1,3,6-trisulfonic acids, trisodium salt (APTS) and cyanine 7.5 (Cy7.5). Combining the results of NIR imaging and HPGPC, we found that DOP was poorly absorbed directly in the prototype form; instead, DOP moved with the intestinal contents to the distal part of the intestine, where Bacteroides aggregated for a prolonged time and was metabolized to oligosaccharide-like substances. In contrast, the digestive degradation of DOP in pseudo-sterile mice with a targeted clearance of Bacteroides significantly weakened, which provided the basis and direction for the subsequent search for more specific metabolic pathways of DOP in vivo.


Asunto(s)
Dendrobium , Animales , Digestión , Alimentos Funcionales , Ratones , Extractos Vegetales , Polisacáridos/metabolismo
20.
Int J Biol Macromol ; 207: 813-825, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35358574

RESUMEN

Angelica sinensis polysaccharide (ASP) has presented increasingly recognized lipid regulation and antioxidant abilities. However, there is little direct evidence to explain why ASP possesses the observed lipid-lowering and anti-oxidation effects. In vivo and in vitro models of alcoholic fatty liver disease (AFLD) were established to examine the direct effect of ASP on hepatic fat accumulation. Our results showed that the lipid-lowering effect of ASP might result from the dual inhibition of lipid synthesis and CD36-mediated lipid uptake. The antioxidation of ASP might be attributed to the reversal of alcohol metabolic pathways from CYP2E1 catalysis to ADH catalysis. Taken together, the study demonstrated the direct role of ASP in lipid metabolism for the first time and revealed the underlying mechanism of reducing ROS, providing an available strategy for ASP as a potential agent to treat AFLD.


Asunto(s)
Angelica sinensis , Hígado Graso , Hígado Graso/metabolismo , Metabolismo de los Lípidos , Lípidos/farmacología , Hígado , Polisacáridos/metabolismo , Polisacáridos/farmacología
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