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1.
Langmuir ; 39(6): 2422-2434, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36734609

RESUMEN

Partial oxidation of methane (CH4) to methanol (CH3OH) remains a great challenge in the field of catalysis due to its low selectivity and productivity. Herein, Ag-O-Ag/graphene and Cu-O-Ag/graphene composite catalysts are proposed to oxidize methane (CH4) to methanol (CH3OH) by using the first-principles calculations. It is shown that reactive oxygen species (µ-O) on both catalysts can activate the C-H bond of CH4, and in addition to CH4 activation, the catalytic activity follows the order of Ag-O-Ag/graphene (singlet) > Ag-O-Ag/graphene (triplet) ≈ Cu-O-Ag/graphene (triplet) > Cu-O-Ag/graphene (singlet). For CH3OH* formation, the catalytic activity follows the order of Cu-O-Ag/graphene (triplet) > Ag-O-Ag/graphene (triplet) > Ag-O-Ag/graphene (singlet) > Cu-O-Ag/graphene (singlet). It can be inferred that the introduction of Cu not only reduces the use of noble metal Ag but also exhibits a catalytic effect comparable to that of the Ag-O-Ag/graphene catalyst. Our findings will provide a new avenue for understanding and designing highly effective catalysts for the direct conversion of CH4 to CH3OH.

2.
Int J Med Sci ; 20(6): 797-809, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37213674

RESUMEN

Currently, no specific and standard treatment for traumatic brain injury (TBI) has been developed. Therefore, studies on new therapeutic drugs for TBI treatment are urgently needed. Trifluoperazine (TFP) is a therapeutic agent for the treatment of psychiatric disorders that reduces edema of the central nervous system. However, the specific working mechanism of TFP is not fully understood in TBI. In this study, the immunofluorescence co-localization analysis revealed that the area and intensity covered by Aquaporin4 (AQP4) on the surface of brain cells (astrocyte endfeet) increased significantly after TBI. In contrast, TFP treatment reversed these phenomena. This finding showed that TFP inhibited AQP4 accumulation on the surface of brain cells (astrocyte endfeet). The tunel fluorescence intensity and fluorescence area were lower in the TBI+TFP group compared to the TBI group. Additionally, the brain edema, brain defect area, and modified neurological severity score (mNSS) were lower in the TBI+TFP. The RNA-seq was performed on the cortical tissues of rats in the Sham, TBI, and TBI+TFP groups. A total of 3774 genes differently expressed between the TBI and the Sham group were identified. Of these, 2940 genes were up-regulated and 834 genes were down-regulated. A total of 1845 differently expressed genes between the TBI+TFP and TBI group were also identified, in which 621 genes were up-regulated and 1224 genes were down-regulated. Analysis of the common differential genes in the three groups showed that TFP could reverse the expression of apoptosis and inflammation genes. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that the differentially expressed genes (DEGs) were highly enriched in the signaling pathways regulating inflammation. In conclusion, TFP alleviates brain edema after TBI by preventing the accumulation of AQP4 on the surface of brain cells. Generally, TFP alleviates apoptosis and inflammatory response induced by TBI, and promotes the recovery of nerve function in rats after TBI. Thus, TFP is a potential therapeutic agent for TBI treatment.


Asunto(s)
Edema Encefálico , Lesiones Traumáticas del Encéfalo , Animales , Ratas , Apoptosis/genética , Acuaporina 4/antagonistas & inhibidores , Acuaporina 4/genética , Acuaporina 4/metabolismo , Encéfalo , Edema Encefálico/etiología , Edema Encefálico/genética , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Lesiones Traumáticas del Encéfalo/genética , Inflamación/tratamiento farmacológico , Inflamación/genética , Inflamación/metabolismo , Trifluoperazina/farmacología , Trifluoperazina/uso terapéutico , Trifluoperazina/metabolismo
3.
BMC Endocr Disord ; 22(1): 231, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36109703

RESUMEN

BACKGROUND: Adiposity evaluated by body mass index (BMI) is associated with glycometabolism. The aim of the investigation was to explore the correlation of visceral fat area (VFA), body fat percentage (BFP), BMI and waist circumference (WC) with type 2 diabetes mellitus (T2DM) and pre-diabetes. METHODS: A total of 18,458 participates underwent physical examination in Nanjing Drum Tower Hospital from January 2018 to April 2022 was included in this study. Data were collected retrospectively. Regression analysis was used to evaluate the relationship of VFA, BFP, WC and BMI with diabetes status, fasting blood glucose (FBG) and glycohemoglobin (HbA1c). RESULTS: After fully adjusted for multiple covariates, VFA, BFP, WC and BMI in T2DM and pre-diabetes group exceeded compared with normal group. FBG was positively correlated with VFA, BFP, WC and BMI with ßs of 2.221,0.306,0.606 and 0.175(p < 0.001). HbA1c was also positively correlated with the four indexes with ßs of 2.645, 0.328, 0.685 and 0.255(p < 0.001). Subgroup analysis shown that FBG and HbA1c were positively correlated with VFA, BFP, BMI and WC in normal and pre-diabetes group (p < 0.001). FBG was negatively correlated with BMI in T2DM group (p = 0.023). In T2DM, there were non-linear relationships of HbA1c with VFA, BFP, WC and BMI with the inflection points for about 7%. Before the inflection point, HbA1c was positively correlated with obesity-related indicators, and it was reversed after the inflection point. In the individuals with excessive VFA and normal BMI, the risk for glycometabolism disorder exceed compared with normal VFA and normal BMI. Every per-standard deviation increasing in VFA, BFP, WC and BMI, the corresponding risk increasing of glycometabolism disorder was 16.4, 14.6, 22.6 and 22.2%. CONCLUSION: The study demonstrated that in adults with T2DM or prediabetes, the VFA, BFP, WC and BMI were higher than with normal glycometabolism. In pre-diabetes and normal population, there were positive correlations of HbA1c and FBG with obesity-related indicators. In T2DM with poor glycemic control (HbA1c > 7%), there might be a trend of fat loss. VFA could negatively affect glycometabolism independently from BMI. The optimum to evaluate the risk of glycometabolism disorder was WC.


Asunto(s)
Diabetes Mellitus Tipo 2 , Estado Prediabético , Adulto , Glucemia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Impedancia Eléctrica , Hemoglobina Glucada , Humanos , Grasa Intraabdominal , Obesidad/diagnóstico , Obesidad/epidemiología , Estado Prediabético/diagnóstico , Estado Prediabético/epidemiología , Estudios Retrospectivos , Factores de Riesgo
4.
Int J Med Sci ; 19(4): 779-788, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35582420

RESUMEN

Traumatic brain injury is a medical event of global concern, and a growing body of research suggests that circular RNAs can play very important roles in traumatic brain injury. To explore the functions of more novel and valuable circular RNA in traumatic brain injury response, a moderate traumatic brain injury in rats was established and comprehensive analysis of circular RNA expression profiles in rat cerebral cortex was done. As a result, 301 up-regulated and 284 down-regulated circular RNAs were obtained in moderate traumatic brain injury rats, the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were performed based on the circular RNA's host genes, and a circRNA-miRNA interaction network based on differentially expressed circular RNAs was constructed. Also, four circular RNAs were validated by RT-qPCR and Sanger sequencing. This study showed that differentially expressed circular RNAs existed between rat cerebral cortex after moderate traumatic brain injury and control. And this will provide valuable information for circular RNA research in the field of traumatic brain injury.


Asunto(s)
Lesiones Traumáticas del Encéfalo , MicroARNs , Animales , Lesiones Traumáticas del Encéfalo/genética , Corteza Cerebral/metabolismo , Ontología de Genes , MicroARNs/genética , MicroARNs/metabolismo , ARN Circular/genética , Ratas
5.
J Environ Manage ; 304: 114286, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34915389

RESUMEN

Carbon emissions from industry and cities have been the focus of global carbon emissions control, but the need to reduce carbon emissions from large agricultural countries cannot be ignored. This study measured rural carbon emissions based on the energy consumption of rural residents and agricultural production from 2000 to 2018 in China, and the spatial-temporal evolution and variation of rural carbon emissions were analyzed using the quadrant diagram method and Theil index, which also further identified the contribution elements of rural carbon emissions. The gradual growth of rural carbon emissions in China's provinces has been accompanied by a spatial clustering of high emissions, and the carbon emissions among the country's eight regions are characterized by large inter-regional and small intra-regional differences. By identifying the carbon emissions contributions of regions and the carbon sources, we found that the provinces in the central region produce the most emissions, with the top 3 of 11 provinces contributing up to 61.56% of the total national production. Furthermore, emissions from the dominant carbon source in rural China, raw coal, has decreased to 49.22%, and the low use of electricity and natural gas results in the structure of rural carbon sources being weakly decarbonized. The decomposition of carbon emissions indicated that rural economic development plays a prominent contributory role in carbon emissions, whereas energy consumption per unit output value has a significant inhibitory effect on carbon emissions. This study contributes to current carbon emission-related research by identifying the main contributors of rural carbon emissions from multiple perspectives.


Asunto(s)
Dióxido de Carbono , Carbono , Carbono/análisis , Dióxido de Carbono/análisis , Huella de Carbono , China , Desarrollo Económico
6.
Nat Prod Rep ; 38(10): 1821-1851, 2021 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-33650613

RESUMEN

Covering: 2010 to 2020Benzocycloheptane is a fundamental and unique structural motif found in pharmaceuticals and natural products. The total syntheses of natural products bearing the benzocycloheptane subunit are challenging and there are only a few efficient approaches to access benzocycloheptane. Thus, new methods and innovative strategies for preparing such natural products need to be developed. In this review, recent progress in the total syntheses of natural products bearing the benzocycloheptane motif is presented, and key transformations for the construction of benzocycloheptane are highlighted. This review provides a useful guide for those engaged in the syntheses of natural products containing the benzocycloheptane motif.


Asunto(s)
Benzocicloheptenos/síntesis química , Productos Biológicos/síntesis química , Reacción de Cicloadición , Compuestos Heterocíclicos de 4 o más Anillos/síntesis química , Hidrocarburos Policíclicos Aromáticos/síntesis química , Estilbenos/síntesis química
7.
Public Health Nutr ; 24(7): 1869-1876, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33308358

RESUMEN

OBJECTIVE: To investigate the prevalence of mental health problems among preschoolers in rural China and examine the relationship between dietary diversity and mental health. DESIGN: A cross-sectional survey analysis was performed. Child mental health was assessed with the Strengths and Difficulties Questionnaire (SDQ). Child dietary diversity was assessed with the dietary diversity score (DDS), which was calculated based on nine food groups using a 24-h recall method. Data were analysed using unadjusted and adjusted logistic regression models. SETTING: Two nationally designated poverty counties in Hunan Province of China. PARTICIPANTS: Preschoolers (n 1334) aged 3-5 years, preschools (n 26). RESULTS: Of 950 preschoolers with data on both dietary diversity and mental health, 663 (70 %) were classified as having at least one kind of mental health problem. The prevalences of emotional symptoms, conduct problems, symptoms of hyperactive/inattention, peer relationship problems and poor prosocial behaviour were 39, 27, 23, 12 and 26 %, respectively. Male preschoolers showed higher risks of having mental health problems than their female counterparts on each SDQ subscale except for conduct problems. Moreover, a higher DDS was significantly associated with a lower likelihood of having symptoms of hyperactivity/inattention, peer relationship problems and prosocial behaviour problems after adjustment for confounders (preschoolers' age, gender, cognitive ability, parental migration status, primary caregiver's education and household socio-economic status). CONCLUSIONS: The prevalence of mental health problems was high among preschoolers in rural China. Improving child dietary diversity might be an important strategy to consider in the design of interventions to improve child mental health.


Asunto(s)
Dieta , Salud Mental , Población Rural , Preescolar , China/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
8.
Clin Infect Dis ; 71(9): 2421-2427, 2020 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-31734699

RESUMEN

BACKGROUND: Evaluation of a licensed inactivated enterovirus type 71 (EV71) vaccine is needed in a phase IV study with a large population to identify its effectiveness and safety for further application. METHODS: An open-label, controlled trial involving a large population of 155 995 children aged 6-71 months was performed; 40 724 were enrolled in the vaccine group and received 2 doses of inactivated EV71 vaccine at an interval of 1 month, and the remaining children were used as the control group. The EV71-infected cases with hand, foot, and mouth disease were monitored in the vaccine and control groups during a follow-up period of 14 months since the 28th day postinoculation through the local database of the Notifiable Infectious Diseases Network. The effectiveness of the vaccine was estimated by comparing the incidence density in the vaccine group versus that in the control group based upon EV71-infected patients identified via laboratory testing. In parallel, the active and passive surveillance for safety of the vaccine was conducted by home or telephone visits and by using the Adverse Event Following Immunization (AEFI) system, respectively. RESULTS: An overall level of 89.7% (95% confidence interval, 24.0-98.6%) vaccine effectiveness against EV71 infection and a 4.58% rate of reported adverse events were observed. Passive surveillance demonstrated a 0.31% rate of reported common minor reactions. CONCLUSIONS: The clinical protection and safety of the EV71 vaccine were demonstrated in the immunization of a large population. CLINICAL TRIALS REGISTRATION: NCT03001986.


Asunto(s)
Enterovirus Humano A , Enterovirus , Enfermedad de Boca, Mano y Pie , Vacunas Virales , Adolescente , Adulto , Anciano , Anticuerpos Antivirales , Niño , Enfermedad de Boca, Mano y Pie/epidemiología , Enfermedad de Boca, Mano y Pie/prevención & control , Humanos , Persona de Mediana Edad , Vacunas de Productos Inactivados/efectos adversos , Adulto Joven
9.
Toxicol Appl Pharmacol ; 397: 115014, 2020 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-32320792

RESUMEN

Spinal cord injury (SCI) is a severe central nervous system injury for which few efficacious drugs are available. Rosmarinic acid (RA), a water-soluble polyphenolic phytochemical, has antioxidant, anti-inflammatory, and anti-apoptotic properties. However, the effect of RA on SCI is unclear. We investigated the therapeutic effect and underlying mechanism of RA on SCI. Using a rat model of SCI, we showed that RA improved locomotor recovery after SCI and significantly mitigated neurological deficit, increased neuronal preservation, and reduced apoptosis. Also, RA inhibited activation of microglia and the release of TNF-α, IL-6, and IL-1ß and MDA. Moreover, proteomics analyses identified the Nrf2 and NF-κB pathways as targets of RA. Pretreatment with RA increased levels of Nrf2 and HO-1 and reduced those of TLR4 and MyD88 as well as phosphorylation of IκB and subsequent nuclear translocation of NF-κB-p65. Using H2O2- and LPS-induced PC12 cells, we found that RA ameliorated the H2O2-induced decrease in viability and increase in apoptosis and oxidative injury by activating the Nrf2/HO-1 pathway. Also, LPS-induced cytotoxicity and increased apoptosis and inflammatory injury in PC-12 cells were mitigated by RA by inhibiting the TLR4/NF-κB pathway. The Nrf2 inhibitor ML385 weakened the effect of RA on oxidant stress, inflammation and apoptosis in SCI rats, and significantly increased the nuclear translocation of NF-κB. Therefore, the neuroprotective effect on SCI of RA may be due to its antioxidant and anti-inflammatory properties, which are mediated by modulation of the Nrf2/HO-1 and TLR4/NF-κB pathways. Moreover, RA activated Nrf2/HO-1, which amplified its inhibition of the NF-κB pathway.

10.
Respir Res ; 21(1): 16, 2020 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-31924204

RESUMEN

BACKGROUND: Lung-protective ventilation (LPV) has been found to minimize the risk of ventilator-induced lung injury (VILI). However, whether LPV is able to diminish ventilator-induced diaphragm dysfunction (VIDD) remains unknown. This study was designed to test the hypothesis that LPV protects the diaphragm against VIDD. METHODS: Adult male Wistar rats received either conventional mechanical (tidal volume [VT]: 10 ml/kg, positive end-expiratory pressure [PEEP]: 2 cm H2O; CV group) or lung-protective (VT: 5 ml/kg, PEEP: 10 cm H2O; LPV group) ventilation for 12 h. Then, diaphragms and lungs were collected for biochemical and histological analyses. Transcriptome sequencing (RNA-seq) was performed to determine the differentially expressed genes in the diaphragms between groups. RESULTS: Our results suggested that LPV was associated with diminished pulmonary injuries and reduced oxidative stress compared with the effects of the CV strategy in rats. However, animals that received LPV showed increased protein degradation, decreased cross-sectional areas (CSAs) of myofibers, and reduced forces of the diaphragm compared with the same parameters in animals receiving CV (p < 0.05). In addition, the LPV group showed a higher level of oxidative stress in the diaphragm than the CV group (p < 0.05). Moreover, RNA-seq and western blots revealed that the peroxisome proliferator-activated receptor γ coactivator-1alpha (PGC-1α), a powerful reactive oxygen species (ROS) inhibitor, was significantly downregulated in the LPV group compared with its expression in the CV group (p < 0.05). CONCLUSIONS: Compared with the CV strategy, the LPV strategy did not protect the diaphragm against VIDD in rats. In contrast, the LPV strategy worsened VIDD by inducing oxidative stress together with the downregulation of PGC-1α in the diaphragm. However, further studies are required to determine the roles of PGC-1α in ventilator-induced diaphragmatic oxidative stress.


Asunto(s)
Diafragma/patología , Pulmón/patología , Debilidad Muscular/patología , Atrofia Muscular/patología , Respiración con Presión Positiva/efectos adversos , Lesión Pulmonar Inducida por Ventilación Mecánica/patología , Animales , Análisis de los Gases de la Sangre/métodos , Diafragma/metabolismo , Pulmón/metabolismo , Masculino , Debilidad Muscular/etiología , Debilidad Muscular/metabolismo , Atrofia Muscular/etiología , Atrofia Muscular/metabolismo , Respiración con Presión Positiva/métodos , Ratas , Ratas Wistar , Lesión Pulmonar Inducida por Ventilación Mecánica/metabolismo
11.
Fish Shellfish Immunol ; 106: 71-78, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32738512

RESUMEN

A new cell line derived from dorsal fin of rabbit fish Siganus fuscescens was developed and characterized. The cell line was isolated from the dorsal fin, named as rabbit fish fin (RFF) cell line, and which was sub-cultured for 50 cycles since the development. This cell line was tested for growth in different temperatures and serum concentrations, and the best growing condition was at 20% serum at 28 °C. In cultured RFF cells, amplification of 18S rRNA from genomic DNA and immunostaining of cellular cytokeratin confirmed the proper identity of S. fuscescens fish. After 30th passage of cultures, the cells were exposed to challenge of inflammation, triggered by LPS, and hypoxia, mimicked by CoCl2. Cultured RFF cells showed robust sensitive responses to inflammation and hypoxia in directing the expressions of cytokines and hypoxia inducible factor-1α (HIF-1α). The water extract of aerial part of Scutellaria baicalensis (SBA) has been shown in rabbit fish to prevent inflammation. Here, we extended this notion of testing the efficacy of SBA extract in the developed cultured RFF cells. Application of SBA extract inhibited the expression of LPS-induced inflammatory cytokines, i.e. IL-1ß, IL-6, as well as the signaling of NF-κB. The application of CoCl2 in cultured RFF cells triggered the hypoxia-induced cell death and up regulation of HIF-1α. As expected, applied SBA extract in the cultures prevented the hypoxia-induced signaling. Our results show the established RFF cell line may be served as an ideal in vitro model in drug screening relating to inflammation and hypoxia. Additionally, we are supporting the usage of SBA herbal extract in fish aquaculture, which possesses efficacy against inflammation and hypoxia.


Asunto(s)
Antiinflamatorios/farmacología , Enfermedades de los Peces/inmunología , Perciformes/inmunología , Extractos Vegetales/farmacología , Animales , Línea Celular , Hipoxia/inmunología , Hipoxia/veterinaria , Subunidad alfa del Factor 1 Inducible por Hipoxia/inmunología , Inflamación/inmunología , Inflamación/veterinaria , FN-kappa B/inmunología , Scutellaria baicalensis , Transducción de Señal/efectos de los fármacos
12.
Mediators Inflamm ; 2020: 6420425, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32273830

RESUMEN

Neuropathic pain is a serious clinical problem to be solved. This study is aimed at investigating protein kinase A (PKA) expression in neuropathic pain and its possible mechanisms of involvement. A neuropathic pain-related gene expression dataset was downloaded from Gene Expression Omnibus, and differentially expressed genes were screened using the R software. cytoHubba was used to screen for hub genes. A spared nerve injury (SNI) rat model was established, and the paw withdrawal threshold was determined using von Frey filaments. Western blotting and immunofluorescence were used to detect the expression and cellular localization, respectively, of key proteins in the spinal cord. Western blot, ELISA, and TUNEL assays were used to detect cell signal transduction, inflammation, and apoptosis, respectively. Pka was identified as a key gene involved in neuropathic pain. After SNI, mechanical allodynia occurred, PKA expression in the spinal cord increased, the p38MAPK pathway was activated, and spinal cord inflammation and apoptosis occurred in rats. PKA colocalized with neurons, astrocytes, and microglia, and apoptotic cells were mainly neurons. Intrathecal injection of a PKA inhibitor not only relieved mechanical hyperalgesia, inflammatory reaction, and apoptosis in SNI rats but also inhibited p38MAPK pathway activation. However, intrathecal injection of a p38MAPK inhibitor attenuated mechanical hyperalgesia, inflammation, and apoptosis, but did not affect PKA expression. In conclusion, PKA is involved in neuropathic pain by activating the p38MAPK pathway to mediate spinal cord cell apoptosis.


Asunto(s)
Apoptosis/fisiología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Neuralgia/metabolismo , Neuralgia/patología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/fisiología , Animales , Apoptosis/genética , Western Blotting , Proteínas Quinasas Dependientes de AMP Cíclico/genética , Ensayo de Inmunoadsorción Enzimática , Imidazoles/farmacología , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Masculino , Piridinas/farmacología , Ratas , Programas Informáticos , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores
13.
Nat Prod Rep ; 36(2): 263-288, 2019 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-30215657

RESUMEN

Covering: January 2012 to January 2018 Sesterterpenoids are a small family of terpenes that often possess intriguing biological profiles and complicated chemical structures. Their total syntheses are usually remarkably challenging, requiring methodological and strategic innovation. In this review, we summarize and discuss the total syntheses of sesterterpenoids published during the coverage period, and the key chemical transformations are highlighted.


Asunto(s)
Terpenos/síntesis química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/síntesis química , Compuestos Bicíclicos con Puentes/síntesis química , Estructura Molecular , Sesquiterpenos/síntesis química , Sesterterpenos/síntesis química
14.
Mol Pharm ; 16(6): 2636-2647, 2019 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-31067065

RESUMEN

G protein-coupled receptors (GPCRs) undergo ligand-induced internalization that carries the cognate ligands into intracellular compartments. The present study explores this property for the use of formyl peptide receptor 1 (FPR1), a class A GPCR that binds formylated peptides, as a potential target for drug delivery. A pH-sensitive peptide-drug conjugate consisting of doxorubicin (DOX), N-ε-maleimidocaproic acid hydrazide (EMCH), and the formyl peptide fMet-Leu-Phe-Cys (abbreviated as DEF) was prepared. DEF retained pharmacological activities of formyl peptides in binding to FPR1 and mobilization of Ca2+ from intracellular stores. However, the conjugated DOX was no longer cell membrane-permeable and relied on FPR1 for cellular entry. DOX was released from DEF into acidic compartments labeled with fluorescent trackers for endosomes. Treatment of cells with pharmacological inhibitors that block clathrin- or caveolae-mediated endocytosis did not abrogate FPR1-dependent DEF internalization, nor did inhibition of macropinocytosis and phagocytosis. In contrast, cholesterol depletion abrogated DEF internalization through FPR1, suggesting characteristics of cholesterol-dependent uptake mediated by a cell surface receptor. These results demonstrate the possibility of using FPR1 for targeted drug delivery.


Asunto(s)
Colesterol/metabolismo , Endocitosis/fisiología , Receptores de Formil Péptido/metabolismo , Cromatografía Líquida de Alta Presión , Endocitosis/genética , Células HeLa , Humanos , Espectrometría de Masas , N-Formilmetionina Leucil-Fenilalanina/metabolismo , Neutrófilos/metabolismo , Receptores de Formil Péptido/genética
15.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3221-3225, 2019 Aug.
Artículo en Zh | MEDLINE | ID: mdl-31602875

RESUMEN

The non-starch polysaccharides,mainly composed of glucomannans,are the major bioactive compounds in Dendrobium catenatum. In order to evaluate the quality of the medicinal materials and guide the production and processing,a quantification method of non-starch polysaccharides was established by stems of D. catenatum C15 strain collected from the pear epiphytic cultivation. The non-starch polysaccharides were obtained by " water extraction,α-amylase pretreatment,and alcohol precipitation once" method. The contents of starches,non-starch polysaccharides and monosaccharides were analyzed. In addition,the system suitability was tested. Compared with method of the Chinese Pharmacopoeia( 2015 edition),the contents of total polysaccharides,glucose,and mannose were decreased by 20. 9%,58. 8% and 1. 6% respectively. The method effectively digested starch and retained non-starch polysaccharides,and the analysis result was accurate and repeatable. Therefore,it is suitable for the content measurement of non-starch polysaccharides of D. catenatum. Furthermore,it could be an alternative method for quality control of D. catenatum and a reference in the determination of non-starch polysaccharides in other starch-containing medicinal materials.


Asunto(s)
Dendrobium/química , Polisacáridos/análisis , Monosacáridos/análisis , Fitoquímicos/análisis , Almidón/análisis
16.
Electrophoresis ; 2018 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-29572877

RESUMEN

Three fractions (I-III) were separated from crude oligosaccharides of lotus seeds by fast protein liquid chromatography with final purity of 97.6, 96.3, and 96.8%, respectively. The fractions were identified as sucrose, raffinose, and stachyose by using TLC, HPLC with charged aerosol detector (CAD), LC-MS, and methylation analysis. Subsequently sucrose and raffinose family oligosaccharides (RFOs) with degree of polymerization (DP) 3-5 (raffinose, stachyose, and verbascose) have been quantified by HPLC-CAD for the first time. All calibration curves for investigated analytes showed good linear regression (R2  > 0.9952). Their limit of detection and limit of quantity were in the ranges 0.14-0.28 and 0.36-0.48 µg/mL, respectively. The recoveries ranged from 96.6 to 103.4%. The contents of sucrose and RFOs DP3-DP5 were different in lotus seeds and other parts of lotus samples, but similar in their own variety. Additionally, the distribution of RFOs in different parts of lotus were also compared and the results indicated that RFOs might be mainly synthesized in lotus seeds. This work is helpful for understanding the way of biosynthesis of RFOs in lotus as well as quality control of plants containing RFOs.

17.
J Sep Sci ; 41(3): 609-617, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29105962

RESUMEN

Salvia miltiorrhiza, also known as Danshen, is a widely used traditional Chinese medicine for the treatment of cardiovascular diseases and hematological abnormalities. The root and rhizome of Salvia przewalskii and Salvia yunnanensis have been found as substitutes for Salvia miltiorrhiza in the market. In this study, the chemical information of 14 major compounds in Salvia miltiorrhiza and its substitutes were determined using a high-performance liquid chromatography method. Stepwise discriminant analysis was adopted to select the characteristic variables. Partial least squares discriminant and hierarchical cluster analysis were performed to classify Salvia miltiorrhiza and its substitutes. The results showed that all of the samples were correctly classified both in partial least squares discriminant analysis and hierarchical cluster analysis based on the four compounds (caffeic acid, rosmarinic acid, salvianolic acid B, and salvianolic acid A). This method can not only distinguish Salvia miltiorrhiza and its substitutes, but also classify Salvia przewalskii and Salvia yunnanensis. The method can be applied for the quality assessment of Salvia miltiorrhiza and identification of unknown samples.


Asunto(s)
Cromatografía Líquida de Alta Presión , Salvia/química , Salvia/clasificación , Algoritmos , Cinamatos/análisis , Depsidos/análisis , Medicamentos Herbarios Chinos/análisis , Modelos Lineales , Panax/química , Reconocimiento de Normas Patrones Automatizadas , Preparaciones de Plantas/análisis , Estándares de Referencia , Reproducibilidad de los Resultados , Salvia miltiorrhiza/química , Temperatura , Ácido Rosmarínico
18.
Molecules ; 23(7)2018 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-30041445

RESUMEN

A green and reliable method using supercritical fluid extraction (SFE) and molecular distillation (MD) was optimized for the separation and purification of standardized typical volatile components fraction (STVCF) from turmeric to solve the shortage of reference compounds in quality control (QC) of volatile components. A high quality essential oil with 76.0% typical components of turmeric was extracted by SFE. A sequential distillation strategy was performed by MD. The total recovery and purity of prepared STVCF were 97.3% and 90.3%, respectively. Additionally, a strategy, i.e., STVCF-based qualification and quantitative evaluation of major bioactive analytes by multiple calibrated components, was proposed to easily and effectively control the quality of turmeric. Compared with the individual calibration curve method, the STVCF-based quantification method was demonstrated to be credible and was effectively adapted for solving the shortage of reference volatile compounds and improving the QC of typical volatile components in turmeric, especially its functional products.


Asunto(s)
Fraccionamiento Químico , Curcuma/química , Destilación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/aislamiento & purificación , Fraccionamiento Químico/instrumentación , Fraccionamiento Químico/métodos , Destilación/instrumentación , Destilación/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación , Reproducibilidad de los Resultados
19.
Molecules ; 23(6)2018 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-29890656

RESUMEN

Ganoderma resinaceum has been used as an ethnomedicine for lowering blood sugar. To clarify the bioactive chemical constituents contributing to lower blood sugar, chemical investigation on the fruiting bodies of Ganoderma resinaceum was conducted by chromatographic techniques, and led to the isolation of 14 compounds. Their structures were elucidated as triterpenoid lactones (1⁻4 and 8) and ganoderma acids (5⁻7 and 9⁻14) based on the analysis of extensive spectroscopy (mass spectrometry (MS), nuclear magnetic resonance (NMR), infrared (IR), and ultraviolet (UV)) and comparison with literature data. Compounds 3, 5, 6, and 9⁻14 were evaluated for α-glucosidase inhibitory activity. Compounds 1⁻7 are new compounds. Compounds 1⁻4 and 8 were characteristic of an oxaspirolactone moiety, consisting of a five-membered ether ring, a five-membered lactone ring, and a characteristic C-23 spiro carbon. It is rare for natural products that such an oxaspirolactone moiety occurred in the lanostane-type triterpenoids. Compounds 5⁻7 and 9⁻14 may be important intermediates of the biosynthetic pathways of 1⁻4 and 8. Compounds 1 and 2 showed more potent inhibitory activity against α-glucosidase compared with the positive control drug acarbose with IC50 value of 0.75 ± 0.018 mM and 1.64 ± 0.022 mM, respectively.


Asunto(s)
Ganoderma/química , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Lactonas/farmacología , Triterpenos/farmacología , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Lactonas/química , Lactonas/aislamiento & purificación , Estructura Molecular , Análisis Espectral/métodos , Triterpenos/química , Triterpenos/aislamiento & purificación
20.
Molecules ; 23(7)2018 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-29958431

RESUMEN

A high-performance liquid chromatography (HPLC) method was investigated for the simultaneous quantification of two chemical types of bioactive compounds in the rhizome of Curcuma longa Linn. (turmeric), including three curcuminoids: Curcumin, bisdemethoxycurcumin, and demethoxycurcumin; and three volatile components: ar-turmerone, ß-turmerone, and α-turmerone. In the present study, the sample extraction system was optimized by a pressurized liquid extraction (PLE) process for further HPLC analysis. The established HPLC analysis conditions were achieved using a Zorbax SB-C18 column (250 mm × 4.6 mm i.d., 5 µm) and a gradient mobile phase comprised of acetonitrile and 0.4% (v/v) aqueous acetic acid with an eluting rate of 1.0 mL/min. The curcuminoids and volatile components were detected at 430 nm and 240 nm, respectively. Moreover, the method was validated in terms of linearity, sensitivity, precision, stability and accuracy. The validated method was successfully applied to evaluate the quality of twelve commercial turmeric samples.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Curcuma/química , Extractos Vegetales/química , Curcumina/análogos & derivados , Curcumina/química , Diarilheptanoides , Cetonas/química , Reproducibilidad de los Resultados , Rizoma/química , Sesquiterpenos/química
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