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1.
Chin J Integr Med ; 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38733455

RESUMEN

OBJECTIVE: To explore the rapid antidepressant potential and the underlying mechanism of Chaihu Shugan San (CSS) in female mice. METHODS: Liquid chromatography mass spectrometry (LC-MS)/MS was used to determine the content of main components in CSS to determine its stability. Female C57BL/6J mice were randomly divided into 4 groups, including control (saline), vehicle (saline), CSS (4 g/kg) and ketamine (30 mg/kg) groups. Mice were subjected to irregular stress stimulation for 4 weeks to establish the chronic mild stress (CMS) model, then received a single administration of drugs. Two hours later, the behavioral tests were performed, including open field test, tail suspension test (TST), forced swimming test (FST), novelty suppression feeding test (NSF), and sucrose preference test (SPT). Western blot analysis was used to detect the expression levels of N-methyl-D-aspartate receptor (NMDA) subtypes [N-methyl-D-aspartate receptor 1 (NR1), NR2A, NR2B], synaptic proteins [synapsin1 and post synaptic density protein 95 (PSD95)], and brain-derived neurotrophic factor (BDNF). Moreover, the rapid antidepressant effect of CSS was tested by pharmacological technologies and optogenetic interventions that activated glutamate receptors, NMDA. RESULTS: Compared with the vehicle group, a single administration of CSS (4 g/kg) reversed all behavioral defects in TST, FST, SPT and NSF caused by CMS (P<0.05 or P<0.01). CSS also significantly decreased the expressions of NMDA subtypes (NR1, NR2A, NR2B) at 2 h in hippocampus of mice (all P<0.01). In addition, similar to ketamine, CSS increased levels of synaptic proteins and BDNF (P<0.05 or P<0.01). Furthermore, the rapid antidepressant effects of CSS were blocked by transient activation of NMDA receptors in the hippocampus (all P<0.01). CONCLUSION: Rapid antidepressant effects of CSS by improving behavioral deficits in female CMS mice depended on rapid suppression of NMDA receptors and activation of synaptic proteins.

2.
Inorg Chem ; 61(49): 20026-20034, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36441952

RESUMEN

To reasonably design and synthesize metal-organic frameworks (MOFs) with high stability and excellent adsorption/separation performance, the pore configuration and functional sites are very important. Here, we report two structurally similar cluster-based MOFs using a pyridine-modified low-symmetry ligand [H4L = 2,6-bis(2',5'-dicarboxyphenyl)pyridine], [(NH2Me2)2][Co5(L)2(OCH3)2(µ3-OH)2·2DMF]·2DMF·2H2O (1) and [Co5(L)2(µ3-OH)2(H2O)2]·2H2O·4DMF (2). The structures of 1 and 2 are built from Co5 clusters, which have one-dimensional open channels, but their microporous environments are different due to the different ways in which ligands bind to the metals. Both MOFs have extremely high chemical stabilities over a wide pH range (2-12). The two MOFs have similar adsorption capacities of C2H2 (144.0 cm3 g-1 for 1 and 141.3 cm3 g-1 for 2), but 1 has a higher C2H2/CO2 selectivity of 3.5 under ambient conditions. The difference in gas adsorption and separation between the two MOFs has been compared by a breakthrough experiment and theoretical calculation, and the influence of the microporous environment on the gas adsorption and separation performance of MOFs has been further studied.


Asunto(s)
Estructuras Metalorgánicas , Dióxido de Carbono , Metales , Adsorción
3.
BMC Musculoskelet Disord ; 23(1): 794, 2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-35986271

RESUMEN

BACKGROUND: Oblique lumbar interbody fusion (OLIF) is an important surgical modality for the treatment of degenerative lumbar spine disease. Various supplemental fixations can be co-applied with OLIF, increasing OLIF stability and reducing complications. However, it is unclear whether osteoporosis affects the success of supplemental fixations; therefore, this study analyzed the effects of osteoporosis on various supplemental fixations co-applied with OLIF. METHODS: We developed and validated an L3-S1 finite element (FE) model; we assigned different material properties to each component and established models of the osteoporotic and normal bone lumbar spine. We explored the outcomes of OLIF combined with each of five supplemental fixations: standalone OLIF; OLIF with lateral plate fixation (OLIF + LPF); OLIF with translaminar facet joint fixation and unilateral pedicle screw fixation (OLIF + TFJF + UPSF); OLIF with unilateral pedicle screw fixation (OLIF + UPSF); and OLIF with bilateral pedicle screw fixation (OLIF + BPSF). Under the various working conditions, we calculated the ranges of motion (ROMs) of the normal bone and osteoporosis models, the maximum Mises stresses of the fixation instruments (MMSFIs), and the average Mises stresses on cancellous bone (AMSCBs). RESULTS: Compared with the normal bone OLIF model, no demonstrable change in any segmental ROM was apparent. The MMSFIs increased in all five osteoporotic OLIF models. In the OLIF + TFJF + UPSF model, the MMSFIs increased sharply in forward flexion and extension. The stress changes of the OLIF + UPSF, OLIF + BPSF, and OLIF + TFJF + UPSF models were similar; all stresses trended upward. The AMSCBs decreased in all five osteoporotic OLIF models during flexion, extension, lateral bending, and axial rotation. The average stress change of cancellous bone was most obvious under extension. The AMSCBs of the five OLIF models decreased by 14%, 23.44%, 21.97%, 40.56%, and 22.44% respectively. CONCLUSIONS: For some supplemental fixations, the AMSCBs were all reduced and the MMSFIs were all increased in the osteoporotic model, compared with the OLIF model of normal bone. Therefore, the biomechanical performance of an osteoporotic model may be inferior to the biomechanical performance of a normal model for the same fixation method; in some instances, it may increase the risks of fracture and internal fixation failure.


Asunto(s)
Osteoporosis , Tornillos Pediculares , Fusión Vertebral , Fenómenos Biomecánicos , Análisis de Elementos Finitos , Humanos , Vértebras Lumbares/cirugía , Osteoporosis/complicaciones , Osteoporosis/cirugía , Rango del Movimiento Articular , Fusión Vertebral/métodos
4.
Front Cell Infect Microbiol ; 12: 801331, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35425717

RESUMEN

The effects of hydrogen sulfide (H2S) on diabetic metabolic disorders are still controversial, and the mechanisms underlying these effects remain largely unknown. This study was conducted to investigate the potential relationship between the gut microbiota and the improvement of diabetic metabolic disorders by exogenous H2S in obese db/db mice. The db/db mice were treated with sodium hydrosulfide (NaHS) (80 µmol/kg), or vehicle for 16 weeks, respectively. We measured the serum H2S, obesity parameters, glucose homeostasis, and triglyceride. The sequencing of bacterial 16S rRNA gene and fungal internal transcribed spacer (ITS) in the cecal contents of NaHS-treated mice was performed to evaluate the gut microbial communities. We found that supplying exogenous H2S for 16 weeks significantly inhibited the increase of serum triglyceride, blood glucose, and insulin levels and altered specifically the gut bacterial microbiota structure in db/db mice. The relative abundance of some bacterial genera was correlated with the H2S or blood glucose level. Indeed, exogenous H2S increased Firmicutes and decreased Bacteroidetes at the phylum level along with changes of abundance of multifarious genera. Among them, Unclassified_Enterobacteriaceae, Prevotella, and Lactobacillus decreased and Unclassified_Ruminococcaceae, Oscillospira, Ruminococcus, Sutterella, and Desulfovibrio increased. For fungi, exogenous H2S decreased the abundance of Candida and Aspergillus. Here we demonstrated that, in diabetes, microbial dysbiosis may not be just limited to bacteria due to the inter-linked metabolic interactions among bacteria and fungi in the gut. The beneficial effects of exogenous H2S on diabetic metabolic disorders are likely associated with the alterations of specific microbiota.


Asunto(s)
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Sulfuro de Hidrógeno , Enfermedades Metabólicas , Micobioma , Animales , Bacterias/genética , Glucemia , Diabetes Mellitus Tipo 2/complicaciones , Enfermedades Metabólicas/complicaciones , Ratones , Ratones Endogámicos , Obesidad/complicaciones , ARN Ribosómico 16S/genética , Triglicéridos
5.
Dalton Trans ; 48(22): 7938-7945, 2019 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-31090755

RESUMEN

A robust Co-based metal-organic framework, [Co3(L)(OH)2(H2O)4]·2DMF·2H2O (1), was synthesized under solvothermal conditions using pyridyl-decorated tetracarboxylic acid, 2,6-di(2',5'-dicarboxylphenyl)pyridine (H4L). Structural analysis demonstrates that 1 is a 3D framework based on 1D alternate Co4 chain units. The desolvated structure of 1a contains 1D open channels with a highly polar pore surface decorated with open metal sites, µ3-OH group and pyridyl group sites, exhibiting multipoint interactions between C2H2 and CO2 molecules. The framework efficiently takes up C2H2 and CO2 with significant selectivity for C2H2 and CO2 over CH4. In addition, the magnetic properties of 1 were investigated and it showed a slow freezing process.

6.
Sci Rep ; 8(1): 17838, 2018 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-30546118

RESUMEN

Ketogulonicigenium vulgare has been widely used in vitamin C two-step fermentation. Four K. vulgare strains (WSH-001, Y25, Hbe602 and SKV) have been completely genome-sequenced, however, less attention was paid to elucidate the reason for the differences in 2-KGA yield on genetic level. Here, a novel K. vulgare SPU B805 with higher 2-keto-L-gulonic acid (2-KGA) yield, was genome-sequenced to confirm harboring one circular chromosome with plasmid free. Comparative genome analyses showed that the absence of plasmid 2 was an important factor for its high 2-KGA productivity. The amino acid biosynthetic pathways in strain SPU B805 are much more complete than those in other K. vulgare strains. Meanwhile, strain SPU B805 harbored a complete PPP and TCA route, as well as a disabled EMP and ED pathway, same as to strain SKV, whereas strain WSH-001, Y25 and Hbe602 harbored complete PPP, ED, TCA pathway and a nonfunctional EMP pathway. The transcriptome of strain SPU B805 validated the carbon metabolism in cytoplasm mainly through the PPP pathway due to its higher transcriptional levels. This is the first time to elucidate the underlying mechanism for the difference in 2-KGA yield, and it is of great significance for strain improvement in the industrial fermentation.


Asunto(s)
Genoma Bacteriano , Metaboloma/fisiología , Rhodobacteraceae , Transcriptoma/fisiología , Rhodobacteraceae/genética , Rhodobacteraceae/metabolismo , Secuenciación Completa del Genoma
7.
Chem Commun (Camb) ; 54(40): 5074-5077, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29707730

RESUMEN

A novel, hydrophilic and recyclable methoxypolyethylene glycol (PEG)-modulated s-triazine-based multifunctional Schiff base/N,P-ligand L9 was prepared and used in Pd-catalyzed Heck-type carbonylative coupling reactions, affording diverse chalcone derivatives and 1,4-dicarbonyl esters in good yields.

8.
Microb Cell Fact ; 17(1): 81, 2018 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-29778095

RESUMEN

BACKGROUND: 2-Keto-L-gulonic acid (2-KGA), the precursor of vitamin C, is currently produced by two-step fermentation. In the second step, L-sorbose is transformed into 2-KGA by the symbiosis system composed of Ketogulonicigenium vulgare and Bacillus megaterium. Due to the different nutrient requirements and the uncertain ratio of the two strains, the symbiosis system significantly limits strain improvement and fermentation optimization. RESULTS: In this study, Ketogulonicigenium robustum SPU_B003 was reported for its capability to grow well independently and to produce more 2-KGA than that of K. vulgare in a mono-culture system. The complete genome of K. robustum SPU_B003 was sequenced, and the metabolic characteristics were analyzed. Compared to the four reported K. vulgare genomes, K. robustum SPU_B003 contained more tRNAs, rRNAs, NAD and NADP biosynthetic genes, as well as regulation- and cell signaling-related genes. Moreover, the amino acid biosynthesis pathways were more complete. Two species-specific internal promoters, P1 (orf_01408 promoter) and P2 (orf_02221 promoter), were predicted and validated by detecting their initiation activity. To efficiently produce 2-KGA with decreased CO2 release, an innovative acetyl-CoA biosynthetic pathway (XFP-PTA pathway) was introduced into K. robustum SPU_B003 by expressing heterologous phosphoketolase (xfp) and phosphotransacetylase (pta) initiated by internal promoters. After gene optimization, the recombinant strain K. robustum/pBBR-P1_xfp2502-P2_pta2145 enhanced acetyl-CoA approximately 2.4-fold and increased 2-KGA production by 22.27% compared to the control strain K. robustum/pBBR1MCS-2. Accordingly, the transcriptional level of the 6-phosphogluconate dehydrogenase (pgd) and pyruvate dehydrogenase genes (pdh) decreased by 24.33 ± 6.67 and 8.67 ± 5.51%, respectively. The key genes responsible for 2-KGA biosynthesis, sorbose dehydrogenase gene (sdh) and sorbosone dehydrogenase gene (sndh), were up-regulated to different degrees in the recombinant strain. CONCLUSIONS: The genome-based functional analysis of K. robustum SPU_B003 provided a new understanding of the specific metabolic characteristics. The new XFP-PTA pathway was an efficient route to enhance acetyl-CoA levels and to therefore promote 2-KGA production.


Asunto(s)
Proteínas Bacterianas/metabolismo , Metabolismo de los Hidratos de Carbono/fisiología , Ingeniería Metabólica/métodos , Rhodobacteraceae/metabolismo , Sorbosa/metabolismo , Sorbosa/análogos & derivados
9.
Int J Syst Evol Microbiol ; 68(5): 1509-1513, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29547095

RESUMEN

A Gram-stain-negative, strictly aerobic, yellow-coloured, motile by gliding and elongated rod-shaped bacterial strain, designated SYP-B1015T, was isolated from the rhizosphere of Artemisia annua L. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain SYP-B1015T belonged to the genus Flavobacterium and had highest 16S rRNA gene sequence similarity to Flavobacterium compostarboris JCM 16527T (98.1 %) and Flavobacterium procerum JCM 30113T (97.2 %). The predominant respiratory quinone for the strain was MK-6, and the major cellular fatty acids were iso-C15 : 0, iso-C15 : 0 3-OH and iso-C17 : 0 3-OH. The polar lipid profile contained phosphatidylethanolamine as a major compound. The DNA G+C content of strain SYP-B1015T was 33.5 mol%. The DNA-DNA relatedness values between strain SYP-B1015T and F. compostarboris JCM 16527T and F. procerum JCM 30113T were 56.5±0.4 and 48.9±1.2 %, respectively. Combining the data from morphological, physiological, biochemical and chemotaxonomic characterizations presented in this study, strain SYP-B1015T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium artemisiae sp. nov. is proposed. The type strain is SYP-B1015T (=CGMCC 1.16115T=KCTC 62025T).


Asunto(s)
Artemisia annua/microbiología , Flavobacterium/clasificación , Filogenia , Rizosfera , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Flavobacterium/genética , Flavobacterium/aislamiento & purificación , Fosfatidiletanolaminas/química , Pigmentación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
10.
J Biomater Sci Polym Ed ; 26(9): 545-57, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25849098

RESUMEN

The facile synthesis of the starch hydrogel with anisotropic microstructure and dynamic behaviors was developed in the presence (A-gel) and absence of DC electric field (B-gel). The microstructures of hydrogels were characterized by environmental scanning electron microscope. Their electro-responsive property of hydrogels was investigated with their storage modulus (G'). The result demonstrates that the G' of A-gel is greater than that of B-gel, and the modulus of A-gel increases along with the external field, which signifies positive electroresponse. In addition, the G' of A-gel and B-gel ((G'(A) and G'(B)) also continuously increases with increasing starch concentration, whereas both the maximum of modulus increment (ΔG' = G'(A)−G'(B) ) and that of modulus increment sensitivity (ΔG'/G'(B)) occur with the starch weight fraction at around 36.5%. To enhance the electro-responsive effects of the hydrogels, dielectric particles were dispersed in the hydrogel. It is found that BaTiO3/chitosan core-shell composite particles significantly enhance the electroresponse of the hydrogel. The mechanism of the electro-response mode is proposed.


Asunto(s)
Materiales Biocompatibles/química , Reactivos de Enlaces Cruzados/química , Glutaral/química , Hidrogeles/química , Almidón/química , Anisotropía , Compuestos de Bario/química , Bioingeniería , Fenómenos Químicos , Quitosano/química , Sistemas de Liberación de Medicamentos , Módulo de Elasticidad , Técnicas Electroquímicas , Fenómenos Mecánicos , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Porosidad , Propiedades de Superficie , Titanio/química
11.
J Colloid Interface Sci ; 289(1): 56-62, 2005 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16009217

RESUMEN

An effective and novel approach to obtaining electrorheological particles with high performance through the formation of host-guest complexes has been achieved. The significant preponderance of the host-guest complex formation is that the host structure can be controlled easily by adding different guests. Based on this point, six supramolecular complexes of beta-cyclodextrin cross-linking polymer with salicylic acid (beta-CDP-1), 5-chlorosalicylic acid (beta-CDP-2), 3,5-dichlorosalicylic acid (beta-CDP-3), 5-nitrosalicylic acid (beta-CDP-4), 3,5-dinitrosalicylic acid (beta-CDP-5), or 3-hydroxy-2-naphthoic acid (beta-CDP-6) particles were synthesized. The electrorheological yield stresses of the suspensions of these particles in silicone oil have been investigated under DC electric fields. It was found that the yield stress of the typical beta-CDP-1 ER fluid was 5.6 kPa in 4 kV/mm, which is much higher than that of pure beta-cyclodextrin polymer (beta-CDP), that of pure salicylic acid as well as that of the mixture of the host with the guest. It is clearly indicated that the formation of supramolecular complexes between beta-CDP and salicylic acid can enhance the ER properties of the host. The similar results for other supramolecular complexes with different guests have also been obtained under the same DC electric fields. The yield stress of supramolecular complexes is strongly affected by the structure of guests. Among the six investigated guests, 3-hydroxy-2-naphthoic acid gave the highest ER property having a yield stress of 9.8 kPa under 4 kV/mm DC while cross-linked with beta-CDP to form beta-CDP-6. The yield stress of beta-CDP-6 was significantly increased by 72% in comparison with that of the pure beta-CDP. However, the yield stress of beta-CDP-1-5 slightly increased by 34-41% as compared with that of the pure beta-CDP. The achieved results indicate that the ER effect of host-guest complexes can be greatly affected by the changes of the tremendous guest structure, whereas the slight guest structural transposition, such as altering different groups of a guest, can only obtain the adjacent electrorheological behavior. The dielectric properties of these host-guest complexes also proved that the ER effect can be affected by the properties of guest.


Asunto(s)
Polímeros/química , beta-Ciclodextrinas/química , Clorobenzoatos , Electroforesis , Estructura Molecular , Naftoles/química , Tamaño de la Partícula , Polímeros/síntesis química , Reología , Salicilatos/química , Ácido Salicílico/química , Aceites de Silicona/química , Electricidad Estática
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