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1.
Nature ; 583(7818): 790-795, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32728239

RESUMEN

Organic-inorganic hybrid perovskites have electronic and optoelectronic properties that make them appealing in many device applications1-4. Although many approaches focus on polycrystalline materials5-7, single-crystal hybrid perovskites show improved carrier transport and enhanced stability over their polycrystalline counterparts, due to their orientation-dependent transport behaviour8-10 and lower defect concentrations11,12. However, the fabrication of single-crystal hybrid perovskites, and controlling their morphology and composition, are challenging12. Here we report a solution-based lithography-assisted epitaxial-growth-and-transfer method for fabricating single-crystal hybrid perovskites on arbitrary substrates, with precise control of their thickness (from about 600 nanometres to about 100 micrometres), area (continuous thin films up to about 5.5 centimetres by 5.5 centimetres), and composition gradient in the thickness direction (for example, from methylammonium lead iodide, MAPbI3, to MAPb0.5Sn0.5I3). The transferred single-crystal hybrid perovskites are of comparable quality to those directly grown on epitaxial substrates, and are mechanically flexible depending on the thickness. Lead-tin gradient alloying allows the formation of a graded electronic bandgap, which increases the carrier mobility and impedes carrier recombination. Devices based on these single-crystal hybrid perovskites show not only high stability against various degradation factors but also good performance (for example, solar cells based on lead-tin-gradient structures with an average efficiency of 18.77 per cent).

2.
BMC Gastroenterol ; 23(1): 442, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38102560

RESUMEN

BACKGROUND: Anal fistula is a common benign anorectal disease that often requires surgical intervention for effective treatment. In recent years, preoperative colonoscopy as a diagnostic tool in patients with anal fistula has garnered increasing attention due to its potential clinical application value. By investigating underlying inflammatory bowel disease (IBD), polyps, and other abnormalities, preoperative colonoscopy can offer insights to refine surgical strategies and improve patient outcomes. METHODS: This retrospective study focused on 1796 patients with various benign anorectal diseases who underwent preoperative intestinal endoscopy and met surgical criteria within the preceding three years at the First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine. Among these patients, 949 diagnosed with anal fistula comprised group A, while 847 patients without anal fistula were assigned to group B for comparison. The investigation encompassed an analysis of general patient information, endoscopic findings, polyp histopathology, distribution of bowel inflammation sites, and results of inflammatory bowel disease assessments between the two patient cohorts. A subgroup analysis was also conducted on 2275 anal fistula patients with no surgical contraindications. This subgroup was categorized into Group A (949 patients who underwent preoperative intestinal endoscopy) and Group C (1326 patients who did not undergo preoperative colonoscopy). The study compared the rates of detecting endoscopic lesions and IBD-related findings between the two subgroups. RESULTS: The study initially confirmed the comparability of general patient information between groups A and B. Notably, the abnormal detection rate in group A was significantly higher than in group B (P < 0.01). In terms of endoscopic findings, the anal fistula group (group A) exhibited higher rates of detecting bowel inflammation, inflammatory bowel disease, and polyps compared to the non-anal fistula group (group B) (P < 0.05). The distribution of inflammation locations indicated higher detection rates in the terminal ileum, ileocecal region, and ascending colon for group A compared to group B (P < 0.05). Although the incidence of IBD in group A was higher than in group B, this difference did not reach statistical significance (P > 0.05). Subsequently, the analysis of the subgroup (groups A and C) revealed a significant disparity in intestinal endoscopic detection rates (P < 0.01) and statistically significant differences in detecting IBD (P < 0.05) and Crohn's disease (P < 0.05) between the two anal fistula subgroups. CONCLUSIONS: The findings of this study underscore the substantial clinical value of preoperative colonoscopy in the comprehensive evaluation of patients with anal fistula. Preoperative colonoscopy aids in ruling out localized perianal lesions caused by underlying inflammatory bowel disease, thereby mitigating the likelihood of missed diagnoses and enhancing treatment outcomes. This research highlights the importance of incorporating preoperative colonoscopy as a valuable diagnostic tool in managing anal fistula patients.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Fístula Rectal , Humanos , Estudios Retrospectivos , Colonoscopía , Fístula Rectal/diagnóstico , Fístula Rectal/cirugía , Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/cirugía , Inflamación
3.
Phytother Res ; 37(11): 5407-5417, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37563852

RESUMEN

Angelica sinensis polysaccharide (ASP) showed increasingly recognized hepatoprotective effects and lipid regulation. Because polysaccharides are typically degraded into fragments or short-chain fatty acids in the gut, rather than being absorbed in their intact form, it is worth pondering why ASP can regulate hepatic lipid metabolism and protect the liver from damage caused by lipid accumulation. In vivo and in vitro nonalcoholic fatty liver disease (NAFLD) models with lipid accumulation were established to investigate the effect and potential mechanisms of ASP on hepatic fat accumulation. Our results showed that ASP remodeled the composition and abundance of the gut microbiota in high-fat diet-fed mice and increased their levels of propionate (0.92 ± 0.30 × 107 vs. 2.13 ± 0.52 × 107 ) and butyrate (1.83 ± 1.31 × 107 vs. 6.39 ± 1.44 × 107 ). Sodium propionate significantly increased the expression of estrogen-related receptor α (ERRα) in liver cells (400 mM sodium propionate for 2.19-fold increase) and alleviated the progress of NAFLD in methionine-choline-deficient diet model. Taken together, our study demonstrated that ASP can regulate hepatic lipid metabolism via propionate/ERRα pathway and ultimately relieving NAFLD. Our findings demonstrate that ASP can be used as a health care product or food supplement to prevent NAFLD.


Asunto(s)
Angelica sinensis , Enfermedad del Hígado Graso no Alcohólico , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Propionatos , Hígado/metabolismo , Polisacáridos/farmacología , Polisacáridos/metabolismo , Dieta Alta en Grasa/efectos adversos , Ratones Endogámicos C57BL , Receptor Relacionado con Estrógeno ERRalfa
4.
J Microencapsul ; 39(1): 25-36, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34859741

RESUMEN

AIM: To prepare the hyaluronic acid-coated Olaparib-loaded PEI - PLGA nanoparticles (HA-Ola-PPNPs) and investigate their tumour-targeted anticancer effect. METHODS: The synthesis of HA-Ola-PPNPs was verified by DLS, TEM and SEM, followed was measured its cytotoxicity using CCK-8 assay. Confocal microscopy was used to observe the cellular uptake. Cell apoptosis was analysed by flow cytometry, biological SEM, and TEM. The expression of related proteins within the tumour site was investigated by immunostaining. RESULTS: The prepared HA-Ola-PPNPs showed a diameter of ∼160 nm with a negatively charged surface (-16.9 ± 2.7 mV) and sustained drug release behaviour. And the encapsulation efficiency of HA-Ola-PPNPs was 78.63 ± 5.29%. HA-Ola-PPNPs exhibited efficient in vitro and in vivo antitumor activities. HA-Ola-PPNPs induced cell apoptosis by upregulating Bax, Cytochrome C, and Caspase 3, downregulating Bcl-2 in breast cancer-bearing mice. CONCLUSIONS: According to the results, the Ola-loaded and HA-coated PEI - PLGA nanoparticles could be considered as a powerful tumour-targeted drug delivery system for TNBC treatment.


Asunto(s)
Nanopartículas , Neoplasias de la Mama Triple Negativas , Animales , Línea Celular Tumoral , Portadores de Fármacos/uso terapéutico , Humanos , Ácido Hialurónico , Ratones , Ftalazinas , Piperazinas , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico
5.
Anal Bioanal Chem ; 413(23): 5715-5724, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34291303

RESUMEN

Acute alcoholic liver injury (AALI) is a threat to human health. Dendrobium officinale polysaccharide (DOP) has the potential to protect the liver by enhancing the anti-oxidative system to maintain the relative balance of ROS (active oxygen species) and antioxidants in AALI mice. However, the dynamic improvement effect of DOP on AALI is still not clear and accurate medication guidance is not available, which limits the clinical application of DOP. Because of the advantages of high sensitivity, noninvasiveness, and visualization, near-infrared (NIR) fluorescence imaging has been widely studied in biochemistry and biomedicine. As the glutathione (GSH) level in the liver is closely related to the progression of AALI, herein, an NIR fluorescent probe for GSH, HCG was used to dynamically evaluate the effect of DOP on AALI mice. In this study, DOP was proven to maintain the relative balance of GSH content in the liver to protect it from damage. To the best of our knowledge, it is the first time to assess the effect of DOP on AALI mice through a NIR fluorescence imaging technique. This study may also provide a potential NIR imaging agent for the clinical research to improve the management of liver injury-related diseases.


Asunto(s)
Dendrobium/química , Hepatitis Alcohólica/prevención & control , Extractos Vegetales/farmacología , Polisacáridos/farmacología , Espectrometría de Fluorescencia/métodos , Espectroscopía Infrarroja Corta/métodos , Enfermedad Aguda , Animales , Glutatión/metabolismo , Hepatitis Alcohólica/metabolismo , Hígado/metabolismo , Ratones
6.
Genomics ; 112(2): 1516-1521, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31470081

RESUMEN

BACKGROUND: We aimed to better clarify the relationship between FTO/MTHFR/TCF7L2 polymorphisms and PCOS in a larger combined population by performing a meta-analysis. METHODS: Eligible articles were retrieved from Pubmed, Embase, Web of Science and CNKI. Review Manager Version was used to perform statistical analyses. RESULTS: Forty-six studies were included for this meta-analysis. FTO rs9939609 polymorphism was found to be significantly associated with PCOS under dominant, recessive, over-dominant and allele comparisons, MTHFR rs1801131 polymorphism was found to be significantly associated with PCOS under recessive and allele comparisons, and MTHFR rs1801133 polymorphism was also found to be significantly associated with PCOS under dominant, recessive and allele comparisons in general population. In subgroup analyses, we found that positive results were mainly driven by the Asians. CONCLUSIONS: Collectively, this meta-analysis proved that FTO rs9939609, MTHFR rs1801131 and MTHFR rs1801133 polymorphisms may serve as predisposing factors of PCOS, especially for Asians.


Asunto(s)
Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Síndrome del Ovario Poliquístico/genética , Polimorfismo de Nucleótido Simple , Proteína 2 Similar al Factor de Transcripción 7/genética , Femenino , Humanos
7.
Org Biomol Chem ; 18(14): 2646-2649, 2020 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-32207506

RESUMEN

The attachment of a dimethylallyl moiety to C4 of 1,3-dihydroxynaphthalene led to spontaneous oxidative cyclisations, resulting in the formation of two tetrahydrobenzofuran and one bicyclo[3.3.1]nonane derivatives. Incubation under an 18O-rich atmosphere proved that both the incorporated oxygen atoms originated from O2. A radical-involved mechanism is proposed for these cyclisations.

8.
J Microencapsul ; 36(4): 356-370, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31190597

RESUMEN

Here, we have successfully synthesised and purified multifunctional PLGA-based nanoparticles by the co-encapsulation of an anticancer drug (tetrandrine) and a magnetic material (Fe3O4). The obtained Tet-Fe3O4-PLGA NPs had a uniform spherical shape with a particle size of approximately 199 nm and a negative surface charge of -18.0 mV, displaying a high encapsulation efficiency. Furthermore, TEM studies provided representative images of the purification process of the magnetic nanoparticles with MACS® technology. The MFM and VSM results indicated that both the Fe3O4 NPs and Tet-Fe3O4-PLGA NPs were superparamagnetic. The DSC spectrum demonstrated that Tet was successfully encapsulated within the PLGA-based nanoparticles. Significantly, the release studies revealed NPs had a relatively slower release rate than free Tet after 8 h's initial burst release, which had decreased from 98% to 65% after 24 h. In vitro cellular studies revealed that NPs could effectively penetrate into A549 cells and A549 multicellular spheroids to exert cytotoxicity, displaying a significantly high anti-proliferation effect. Moreover, western blot demonstrated that the co-loaded NPs had a higher anticancer activity by injuring lysosomes to activate the mitochondria pathway and induce A549 cell apoptosis. The magnetic characteristics and high anticancer activity support the use of Tet/Fe3O4 co-loaded PLGA-based nanoparticles as a promising strategy in the treatment of lung cancer.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Bencilisoquinolinas/administración & dosificación , Portadores de Fármacos/química , Nanopartículas de Magnetita/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Células A549 , Antineoplásicos Fitogénicos/farmacocinética , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Bencilisoquinolinas/farmacocinética , Bencilisoquinolinas/farmacología , Liberación de Fármacos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico
9.
Molecules ; 21(4): 515, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27104499

RESUMEN

Hypericum japonicum (Guttiferae), a type of annual or perennial herb, has been historically applied to cure infectious hepatitis, acute and chronic hepatitis, gastrointestinal disorder, and internal hemorrhage. In our successive studies on the genus Hypericum, two new α-pyrones termed japopyrones A and B (1 and 2) were isolated from H. japonicum. Their structures and absolute configurations were established by the comprehensive analyses of spectroscopic data, the application of the Single-crystal X-ray diffraction structural analysis, and the experimental electronic circular dichroism (ECD) spectra. Bioactivity screenings suggested that compound 2 possessed the potential inhibition efficacy on lytic replication of Kaposi's sarcoma associated herpesvirus (KSHV) with an IC50 29.46 µM and a selective index of higher than 6.79, respectively.


Asunto(s)
Hypericum/química , Lactonas/química , Lactonas/aislamiento & purificación , Pironas/química , Pironas/aislamiento & purificación , Antivirales/química , Antivirales/aislamiento & purificación , Antivirales/farmacología , Línea Celular , Dicroismo Circular , Herpesvirus Humano 8/efectos de los fármacos , Humanos , Lactonas/farmacología , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Pironas/farmacología , Replicación Viral/efectos de los fármacos , Difracción de Rayos X
10.
Molecules ; 21(3): 383, 2016 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-27007360

RESUMEN

Zanthoxylum schinifolium Sieb. et Zucc. (Rutaceae), a dioecious shrub with hooked prickly branches, has been used as folk medicine for the treatment of the common cold, stomach ache, diarrhea, and jaundice in China, Korea, and Japan. In our phytochemical investigations on this genus, a new megastigmane sesquiterpenoid, which is referred to as schinifolenol A (1), was isolated from Z. schinifolium. The stereochemistry was characterized via the analyses of extensive spectra. The absolute configuration was established by the application of a modified Mosher's experiment and assisted by a time-dependent density functional theory (TD-DFT) on calculated electronic circular dichroism (ECD). Bioactivity screenings showed that compound 1 exhibited a safe hypotoxicity and a better selectivity on anti-Kaposi's sarcoma associated herpes virus (KSHV).


Asunto(s)
Ciclohexanonas/administración & dosificación , Glucósidos/administración & dosificación , Herpesvirus Humano 8/efectos de los fármacos , Norisoprenoides/administración & dosificación , Sarcoma de Kaposi/tratamiento farmacológico , Zanthoxylum/química , Dicroismo Circular , Ciclohexanonas/química , Glucósidos/química , Herpesvirus Humano 8/patogenicidad , Humanos , Estructura Molecular , Norisoprenoides/química , Fitoquímicos/administración & dosificación , Fitoquímicos/química , Extractos Vegetales/química , Sarcoma de Kaposi/virología
11.
Phytother Res ; 28(12): 1837-45, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25111860

RESUMEN

The aim of the study was to evaluate the pro-apoptotic effects of polysaccharides derived from Lentinus edodes and further elucidated the mechanisms of this action. Our results demonstrated that marked morphological changes of apoptosis were observed after treatment of L. edodes polysaccharides [Lentinan (LTN)]. Moreover, LTN-induced cell apoptosis was characterized by a rapid stimulation of reactive oxygen species production, the loss of mitochondrial membrane potential and an increase in intracellular concentration of Ca(2+) . In addition, the results of the haematoxylin and eosin and TUNEL assay further confirmed that LTN-induced apoptosis in vivo. Furthermore, flow cytometry analysis showed that LTN could arrest the cell cycle at G2/M phase, and immunofluorescence showed LTN caused disruption of microtubule. These results suggest that disruption of cellular microtubule network, arrest of the cell cycle at G2/M phase and induction of apoptosis may be one of the possible mechanisms of anti-tumour effect of LTN.


Asunto(s)
Apoptosis/efectos de los fármacos , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Lentinano/farmacología , Microtúbulos/ultraestructura , Hongos Shiitake/química , Animales , Calcio/metabolismo , División Celular , Línea Celular Tumoral , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Especies Reactivas de Oxígeno/metabolismo
12.
Behav Sci (Basel) ; 14(8)2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39199119

RESUMEN

In recent years, enterprises have increasingly recognized the pivotal role of external users in driving product innovation. Open innovation platforms (OIPs), which facilitate interactions between companies and external innovators, have emerged as critical conduits in this regard. However, OIP managers face the challenge of motivating innovators to sustain their contributions. While some OIPs have implemented material incentives, the impact of such rewards on users' ongoing innovation efforts remains uncertain. This study utilized a large-scale dataset from an OIP to examine how performance-contingent material rewards influence the subsequent behaviors of online innovators. Employing a quasi-experimental design involving propensity score matching (PSM) and difference-in-differences (DID) analysis, we found that receiving performance-contingent material rewards led to a decrease in the quantity of subsequent ideas generated by innovators. However, these rewarded innovators produced ideas of higher quality. Interestingly, the novelty of ideas submitted by innovators declined following their receiving of rewards. Moreover, newly enlisted innovators exhibited a more positive response to these incentives. Our findings provide valuable insights for platform managers seeking to optimize incentive mechanisms. We suggest adopting diversified incentive approaches and refining incentive strategies to effectively motivate continuous innovation among users on OIPs.

13.
Int J Biol Macromol ; 277(Pt 2): 134236, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39079564

RESUMEN

Natural polysaccharides exhibit a wide range of biological activities, which are closely related to their structural characteristics, including their molecular weight distribution, size, monosaccharide composition, glycosidic bond types and spatial conformation, etc. Size exclusion chromatography (SEC) and asymmetrical flow field-flow fractionation (AF4), as two potent separation techniques, both harbor potential for continuous development and enhancement. This manuscript reviewed the fundamental principles and separation applications of SEC and AF4. The structural information and spatial conformation of polysaccharides can be obtained using SEC or AF4 coupled with multiple detectors. In addition, this manuscript elaborates in detail on the shear degradation of samples such as polysaccharides separated by SEC. In addition, the abnormal elution that occurs during the application of the two methods is also discussed. Both SEC and AF4 possess considerable potential for ongoing development and refinement, thereby offering increased possibilities and opportunities for polysaccharide separation and characterization.


Asunto(s)
Cromatografía en Gel , Fraccionamiento de Campo-Flujo , Peso Molecular , Polisacáridos , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Cromatografía en Gel/métodos , Fraccionamiento de Campo-Flujo/métodos , Monosacáridos/química , Monosacáridos/análisis
14.
Int J Biol Macromol ; 256(Pt 2): 128016, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37967601

RESUMEN

Iron deficiency anemia (IDA) is a common micronutrient deficiency among pregnant women with deleterious maternal and fetal outcomes. Angelica sinensis polysaccharide (ASP) has been shown to reduce hepcidin expression in IDA rats. However, the role of ASP in the treatment of IDA during pregnancy and its potential mechanisms have not been investigated. Moreover, the effect of ASP on duodenal iron absorption is not clear. The aim of this study was to investigate the preventive efficacy of ASP against IDA during pregnancy and clarify the underlying mechanisms. Our results showed that ASP improved maternal hematological parameters, increased serum iron, maternal tissue iron, and fetal liver iron content, and improved pregnancy outcomes. Additionally, ASP combated oxidative stress caused by iron deficiency by improving the body's antioxidant capacity. Western blot results demonstrated that ASP downregulated hepcidin expression by blocking the BMP6/SMAD4, JAK2/STAT3 and TfR2/HFE signaling pathways, which in turn increased the expression of FPN1 in the liver, spleen, and duodenum and promoted iron cycling in the body. Furthermore, ASP increased the expression of DMT1 and Dcytb in the duodenum, thereby facilitating duodenal iron uptake. Our results suggest that ASP is a potential agent for the prevention and treatment of IDA during pregnancy.


Asunto(s)
Angelica sinensis , Hepcidinas , Humanos , Embarazo , Ratas , Femenino , Animales , Hepcidinas/metabolismo , Hierro/metabolismo , Angelica sinensis/metabolismo , Ratas Sprague-Dawley , Polisacáridos/farmacología
15.
Org Lett ; 26(32): 6889-6893, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39106520

RESUMEN

Herein we unveil a visible-light-driven transition-metal-free 1,3-bromodifluoroallylation of [1.1.1]propellane. This reactivity is harnessed through organophotocatalysis, providing practical synthetic pathways to 1-brominated-3-gem-difluoroallylic bicyclo[1.1.1]pentane derivatives, particularly derived from readily available α-trifluoromethylalkenes and inexpensive KBr salts utilized as precursors for bromine radicals. Mechanistic investigations reveal that bromide anions quench the excited state of the photocatalyst, leading to the formation of bromine radicals, which react in a strain-release radical addition process rather than hydrogen atom abstraction with [1.1.1]propellane.

16.
Org Lett ; 26(2): 536-541, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38179934

RESUMEN

In the presence of visible light irradiation, organophoto/nickel dual catalysts, and the mild base K2HPO4, 1,3-enynes react with silanecarboxylic acids to give the corresponding α-silylallenes with high selectivity. In this uniquely decarboxylative hydrosilylation of 1,3-enynes, a silyl radical process is involved and diverse electron-rich and -poor substrates proceed smoothly in moderate to excellent yields. This transformation is particularly synthetically worthwhile when using MeOD as the solvent, which furnishes new access to α-silyldeuteroallenes.

17.
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
18.
PLoS One ; 19(2): e0298329, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38412183

RESUMEN

Monitoring the temperature to determine the fire source locations is essential for controlling the spontaneous combustion in the goaf. Optical fiber sensors are employed to measure the temperature distribution in the goaf. However, due to changes in the geological conditions and the influence of the falling rocks in the goaf, only sensors on the upper side of the uncompacted goaf, due to inclination and coal pillar, may remain. Unilateral sensors are located on the upper side of the goaf, while fire occurs in the center. To investigate the issue with linear unilateral sensors, a two-dimensional inverse method has been developed to determine the location of fire sources by considering heat transfer after a fire inside the goaf. The equations were theoretically solved using Green's function method to obtain the internal temperature distribution of the physical model of the goaf. Sensitivity analysis identified the most crucial parameters in the process of spontaneous heating at different temperature. The fire source location can be determined using a loop method based on the model calculations. We considered a case to validate the model. Accurately identifying the fire source location in the goaf using the unilateral sensors has an essential theoretical and practical significance for fire prevention and fighting.


Asunto(s)
Minas de Carbón , Incendios , Fibras Ópticas , Minas de Carbón/métodos , Combustión Espontánea , Carbón Mineral
19.
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
20.
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
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