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1.
Mol Ther ; 31(4): 1017-1032, 2023 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-36698311

RESUMEN

Sepsis, a critical condition resulting from the systemic inflammatory response to a severe microbial infection, represents a global public health challenge. However, effective treatment or intervention to prevent and combat sepsis is still lacking. Here, we report that hyodeoxycholic acid (HDCA) has excellent anti-inflammatory properties in sepsis. We discovered that the plasma concentration of HDCA was remarkably lower in patients with sepsis and negatively correlated with the severity of the disease. Similar changes in HDCA levels in plasma and cecal content samples were observed in a mouse model of sepsis, and these changes were associated with a reduced abundance of HDCA-producing strains. Interestingly, HDCA administration significantly decreased systemic inflammatory responses, prevented organ injury, and prolonged the survival of septic mice. We demonstrated that HDCA suppressed excessive activation of inflammatory macrophages by competitively blocking lipopolysaccharide binding to the Toll-like receptor 4 (TLR4) and myeloid differentiation factor 2 receptor complex, a unique mechanism that characterizes HDCA as an endogenous inhibitor of inflammatory signaling. Additionally, we verified these findings in TLR4 knockout mice. Our study highlights the potential value of HDCA as a therapeutic molecule for sepsis.


Asunto(s)
Microbioma Gastrointestinal , Sepsis , Animales , Ratones , Inflamación , Lipopolisacáridos , Ratones Endogámicos C57BL , Sepsis/tratamiento farmacológico , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo
2.
Ecotoxicol Environ Saf ; 271: 115998, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38262091

RESUMEN

BACKGROUND: Per- and poly-fluoroalkyl substances (PFAS) are ubiquitous chemicals in the environment and our daily lives. Several epidemiological studies have revealed that PFAS exposure is linked to male sex hormone levels; however, the conclusions are inconsistent across studies. Consequently, we performed a meta-analysis to systematically evaluate the association between PFAS exposure and male sex hormones. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) standards were followed during the meta-analysis. PubMed, Wed of Science, Embase, Cochrane Library, and Ovid databases were used to identify suitable articles before June 2023. The 95% CI and ß values were calculated to assess the association between male sex hormone levels and PFAS exposure. Heterogeneity among the included studies was tested using inconsistency statistics (I2). RESULTS: The literature search identified 12 published articles that met our search criteria, involving 7506 participants. Our results revealed that perfluorononanoic acid (PFNA) and perfluorooctanoic acid (PFOA) exposures were negatively correlated with testosterone (ß = -0.05; 95% CI: -0.09, -0.02, P = 0.003) and (ß = -0.04; 95% CI: -0.08, 0.00, P = 0.049), respectively. CONCLUSION: Exposure to PFNA and PFOA is negatively correlated with changes in male testosterone levels. This correlation suggests that we need to pay attention in the future to whether they are potential risk factors for male reproductive health.


Asunto(s)
Ácidos Alcanesulfónicos , Caprilatos , Contaminantes Ambientales , Ácidos Grasos , Fluorocarburos , Humanos , Masculino , Contaminantes Ambientales/toxicidad , Fluorocarburos/toxicidad , Hormonas Esteroides Gonadales , Testosterona
3.
J Transl Med ; 21(1): 146, 2023 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-36829161

RESUMEN

BACKGROUND: Kidney cancer undergoes a dramatic metabolic shift and has demonstrated responsiveness to immunotherapeutic intervention. However, metabolic classification and the associations between metabolic alterations and immune infiltration in Renal cell carcinoma still remain elucidative. METHODS: Unsupervised consensus clustering was conducted on the TCGA cohorts for metabolic classification. GESA, mRNAsi, prognosis, clinical features, mutation load, immune infiltration and differentially expressed gene differences among different clusters were compared. The prognosis model and nomograms were constructed based on metabolic gene signatures and verified using external ICGC datasets. Immunohistochemical results from Human Protein Atlas database and Tongji hospital were used to validate gene expression levels in normal tissues and tumor samples. CCK8, apoptosis analysis, qPCR, subcutaneously implanted murine models and flowcytometry analysis were applied to investigate the roles of ACAA2 in tumor progression and anti-tumor immunity. RESULTS: Renal cell carcinoma was classified into 3 metabolic subclusters and the subcluster with low metabolic profiles displayed the poorest prognosis, highest invasiveness and AJCC grade, enhanced immune infiltration but suppressive immunophenotypes. ACAA2, ACAT1, ASRGL1, AKR1B10, ABCC2, ANGPTL4 were identified to construct the 6 gene-signature prognosis model and verified both internally and externally with ICGC cohorts. ACAA2 was demonstrated as a tumor suppressor and was associated with higher immune infiltration and elevated PD-1 expression of CD8+ T cells. CONCLUSIONS: Our research proposed a new metabolic classification method for RCC and revealed intrinsic associations between metabolic phenotypes and immune profiles. The identified gene signatures might serve as key factors bridging tumor metabolism and tumor immunity and warrant further in-depth investigations.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Animales , Ratones , Linfocitos T CD8-positivos , Apoptosis , Análisis por Conglomerados , Pronóstico , Microambiente Tumoral
4.
Phytother Res ; 37(11): 5017-5040, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37491018

RESUMEN

The aging of the world population and increasing stress levels in life are the major cause of the increased incidence of neurological disorders. Alzheimer's disease (AD) creates a huge burden on the lives and health of individuals and has become a big concern for society. Triterpenoid saponins (TS), representative natural product components, have a wide range of pharmacological bioactivities such as anti-inflammation, antioxidation, antiapoptosis, hormone-like, and gut microbiota regulation. Notably, some natural TS exhibited promising neuroprotective activity that can intervene in AD progress, especially in the early stage. Recently, studies have indicated that TS play a pronounced positive role in the prevention and treatment of AD. This review discusses the recent research on the neuroprotection of TS and proceeds to detail the action mechanisms of TS against AD, hoping to provide a reference for drug development for anti-AD.


Asunto(s)
Enfermedad de Alzheimer , Saponinas , Triterpenos , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Neuroprotección , Saponinas/farmacología , Saponinas/uso terapéutico , Triterpenos/farmacología , Triterpenos/uso terapéutico
5.
Chem Biodivers ; 20(8): e202300646, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37358391

RESUMEN

The abnormal uterine bleeding (AUB) is complex and usually leads to severe anemia. Melastomadodecandrum (MD) is clinically used for the treatment of metrorrhagia bleeding. The MD ellagitannins (MD-ETs) had been evidenced being effective at hemorrhage, and exerts biological activities upon their metabolites including ellagic acid and urolithins. In this study, the blood-permeated metabolites from theMD-ETs were analyzed using LC-MS approach, and 19 metabolites including ellagic acid and urolithin A derivatives were identified. Furthermore, a network pharmacology analysis including the target prediction analysis, AUB target analysis, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were conducted to reveal the relationships between "metabolites-targets-pathways", which was further verified by molecular docking analysis. The results showed that methyl ellagic acid, urolithin A and isourolithin A produced from MD-ETs can be absorbed into the blood, and might act on the core targets of VEGFA, SRC, MTOR, EGFR and CCND1. And the hemostatic effects were exerted through PI3K-Akt, endocrine resistance and Rap 1 signaling pathways. These results implied the potential effective constituents and action mechanism of MD-ETs in the therapy of AUB, which will promote the application of MD-ETs as natural agent for the treatment of gynecological bleeding diseases.


Asunto(s)
Medicamentos Herbarios Chinos , Taninos Hidrolizables , Femenino , Humanos , Taninos Hidrolizables/farmacología , Taninos Hidrolizables/uso terapéutico , Ácido Elágico , Simulación del Acoplamiento Molecular , Farmacología en Red , Fosfatidilinositol 3-Quinasas , Hemorragia Uterina
6.
Phytochem Anal ; 34(2): 209-224, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36529143

RESUMEN

INTRODUCTION: Eleutherococcus senticosus fruit (ESF) is a natural health supplement resource that has been extensively applied as a tonic for the nervous system. The structures and neural bioactivities of triterpenoid saponins (TS), which are the major constituents of ESF, have not been comprehensively analyzed thus far. OBJECTIVE: We conducted a complete in-depth MS/MS molecular networking (MN)-based targeted analysis of TS from the crude extract of ESF and investigated its neuroprotective value. METHODS: An MS/MS MN-guided strategy was used to rapidly present a series of precursor ions (PIs) of TS in a compound cluster as TS-targeted information used in the discovery and characterization of TS. In addition, a prepared TS-rich fraction of ESF was assayed for its restraining effects on ß-amyloid-induced inhibition of neurite outgrowth. RESULTS: A total of 87 TS were discovered using a PI tracking strategy, 28 of which were characterized as potentially undescribed structures according to their high-resolution MS values. Furthermore, the TS-rich fraction can significantly reduce ß-amyloid-induced damage to neural networks by promoting the outgrowth of neurites and axons. CONCLUSION: Our findings reveal the richness of TS in ESF and will accelerate their application in the treatment of neurodegenerative diseases.


Asunto(s)
Eleutherococcus , Saponinas , Triterpenos , Espectrometría de Masas en Tándem , Extractos Vegetales/química , Eleutherococcus/química , Saponinas/química , Frutas/química , Triterpenos/análisis
7.
Phytother Res ; 36(9): 3490-3504, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35844057

RESUMEN

Eleutherococcus senticosus is a medicinal plant widely used in traditional medicine and edible remedies with effects on anti-fatigue, sleep improvement, and memory enhancement. Recently, the application of E. senticosus to neurological disorders has been a focus. However, its overall pharmacological effect on neural diseases and relevant mechanisms are needed in an in-depth summary. In this review, the traditional uses and the therapeutic effect of E. senticosus on the treatment of fatigue, depression, Alzheimer's disease, Parkinson's disease, and cerebral ischemia were summarized. In addition, the underlying mechanisms involved in the anti-oxidative damage, anti-inflammation, neurotransmitter modulation, improvement of neuronal growth, and anti-apoptosis were discussed. This review will accelerate the understanding of the neuroprotective effects brought from the E. senticosus, and impetus its development as a phytotherapy agent against neurological disorders.


Asunto(s)
Eleutherococcus , Enfermedades del Sistema Nervioso , Plantas Medicinales , Antiinflamatorios/farmacología , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico
8.
Molecules ; 27(8)2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35458705

RESUMEN

Obesity is an important cause of diseases such as type 2 diabetes, non-alcoholic fatty liver and atherosclerosis. The use of ingredients extracted from traditional Chinese medicine for weight loss is now receiving more and more attention. Ginseng has been recorded since ancient times for the treatment of diabetes. The (20R)-Panaxadiol (PD) belongs to the ginseng diol type compounds, which are moderately bioavailable and may remain in the intestinal tract for a longer period of time. This study investigated the potential positive effect of PD in ob/ob mice and evaluated its effect against obesity. The ob/ob mice were administered PD for ten weeks. Our study showed that PD could improve obesity, glucose tolerance disorder, as well as gut dysbiosis. Panaxadiol decreased ob/ob mice's Firmicutes/Bacteroidetes (F/B). Furthermore, 16S rRNA gene sequencing of the fecal microbiota suggested that PD changed the composition of the gut microbiota in ob/ob mice and modulated specific bacteria such as lactobacillus, prevotellace and so on. Moreover, PD improved the intestinal wall integrity. In conclusion, our results suggest that (20R)-Panaxadiol, as an active ingredient of the traditional Chinese medicinal herb ginseng, may improve obesity to some extent via improving gut microbiota.


Asunto(s)
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Panax , Animales , Diabetes Mellitus Tipo 2/complicaciones , Dieta Alta en Grasa , Ginsenósidos , Ratones , Ratones Endogámicos C57BL , Obesidad/etiología , ARN Ribosómico 16S/genética
9.
Nutr J ; 20(1): 65, 2021 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-34238307

RESUMEN

BACKGROUND: Anemia in pregnancy is behind a significant burden of maternal mortality and poor birth outcomes globally. Efforts to address it need evidence on trends and its pertinent factors as they vary from one area to another. METHODS: We pooled data of 23,203 women of reproductive age whose hemoglobin levels were measured from two Tanzania Demographic and Health Surveys (TDHS). Of them, 2,194 women were pregnant. Analyses employed descriptive analyses to determine the burden of anemia, its characteristics, and severity; GIS mapping to determine the regional changes of anemia between 2005 and 2015; and logistic regression to determine the remaining determinants of anemia among pregnant women using Stata 15. RESULTS: The burden of anemia among pregnant women in Tanzania has remained unprecedently high, and varies between regions. There was no significant decline of anemia in general between the two periods after adjusting for individual, households, reproductive, and child characteristics [AOR = 0.964, 95% CI = 0.774-1.202, p = 0.747). Anemia is currently prevalent in 57% of pregnant women in Tanzania. The prevalence is more likely to be higher among women aged 15-19 years than those aged between 20-34 years. It is more likely to be prevalent among those within large families, with no formal education, food insecurity, lack of health insurance, had no antimalaria during pregnancy, and had low frequency of ANC attendance. On the other hand, delivery in a health facility may be potentially protective against anemia. CONCLUSIONS: Anemia in pregnancy remained persistently high and prevalent among 57% of pregnant women in Tanzania. Efforts to address anemia are crucial and need to be focused in regions with increasing burden of anemia among pregnant women. It is imperative to address important risk factors such as food insecurity, strengthening universal health coverage, empowering women of reproductive age with education and especially nutritional knowledge and advocating for early antenatal booking, attendance, and facility delivery.


Asunto(s)
Anemia , Mujeres Embarazadas , Adulto , Anemia/epidemiología , Niño , Estudios Transversales , Composición Familiar , Femenino , Humanos , Embarazo , Atención Prenatal , Prevalencia , Tanzanía/epidemiología , Adulto Joven
10.
Risk Anal ; 41(7): 1145-1151, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-30726556

RESUMEN

Building an interdisciplinary team is critical to disaster response research as it often deals with acute onset events, short decision horizons, constrained resources, and uncertainties related to rapidly unfolding response environments.  This article examines three teaming mechanisms for interdisciplinary disaster response research, including ad hoc and/or grant proposal driven teams, research center or institute based teams, and teams oriented by matching expertise toward long-term collaborations. Using hurricanes as the response context, it further examines several types of critical data that require interdisciplinary collaboration on collection, integration, and analysis. Last, suggesting a data-driven approach to engaging multiple disciplines, the article advocates building interdisciplinary teams for disaster response research with a long-term goal and an integrated research protocol.


Asunto(s)
Planificación en Desastres/métodos , Desastres , Investigación Interdisciplinaria , Investigadores , Humanos
11.
Sensors (Basel) ; 21(12)2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-34207856

RESUMEN

Focusing on the diversified demands of location privacy in mobile social networks (MSNs), we propose a privacy-enhancing k-nearest neighbors search scheme over MSNs. First, we construct a dual-server architecture that incorporates location privacy and fine-grained access control. Under the above architecture, we design a lightweight location encryption algorithm to achieve a minimal cost to the user. We also propose a location re-encryption protocol and an encrypted location search protocol based on secure multi-party computation and homomorphic encryption mechanism, which achieve accurate and secure k-nearest friends retrieval. Moreover, to satisfy fine-grained access control requirements, we propose a dynamic friends management mechanism based on public-key broadcast encryption. It enables users to grant/revoke others' search right without updating their friends' keys, realizing constant-time authentication. Security analysis shows that the proposed scheme satisfies adaptive L-semantic security and revocation security under a random oracle model. In terms of performance, compared with the related works with single server architecture, the proposed scheme reduces the leakage of the location information, search pattern and the user-server communication cost. Our results show that a decentralized and end-to-end encrypted k-nearest neighbors search over MSNs is not only possible in theory, but also feasible in real-world MSNs collaboration deployment with resource-constrained mobile devices and highly iterative location update demands.


Asunto(s)
Seguridad Computacional , Privacidad , Algoritmos , Confidencialidad , Red Social
12.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3908-3914, 2020 Aug.
Artículo en Zh | MEDLINE | ID: mdl-32893588

RESUMEN

G-quadruplex DNA has become an important target for tumor therapy and anti-tumor development. Modern pharmacology has proved that Macleaya cordata has anti-inflammatory, antibacterial, anti-tumor and other pharmacological effects. Affinity ultrafiltration method can screen active ingredients from compounds rapidly, but G-quadruplex DNA ligands are difficult to dissociate, which is a key step in conventional ultrafiltration method. In this paper, the filtrates after ultrafiltration were determined by HPLC-MS in substitution. The peaks with 20% reduction of MS response from the incubation vs control were considered to be ligand components to G-quadruplex. Two of the peaks with the relative abundance above 30% were identified as sanguinarine(SAN) and chelerine(CHE). Their circular dichroism conformations further proved that SAN and CHE are active ligands of HT4. In addition, another two gradients with high relative abundance were identified as protopine(PRO) and allpcryprotopine(ALL). The binding rate of SAN, CHE, PRO and ALL was calculated according to the HPLC-MS results, and the results showed a consistency with that of the molecular docking method. The proposed method can be used to screen active components from mixture.


Asunto(s)
G-Cuádruplex , Ultrafiltración , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Ligandos , Espectrometría de Masas , Simulación del Acoplamiento Molecular
13.
Zhongguo Zhong Yao Za Zhi ; 45(12): 2792-2799, 2020 Jun.
Artículo en Zh | MEDLINE | ID: mdl-32627452

RESUMEN

Cinnamomum cassis is one of the commonly used traditional Chinese medicines in China. Its genuine producing areas distribute in Guangdong and Guangxi provinces. As an important edible herb and export variety of China, the quality control and internationalization of quality standards of C. cassis is extremely significant. In the recent years, with the development of the cinnamon industry, relevant academic research and the upgrade of the international standards, it is necessary to summarize the quality-related progress of C. cassis. In the present review, the germplasm resources, specific quality marker(Q-marker) and quality standards of C. cassis were summarized on the basis of published research during the last 10 years.


Asunto(s)
Cinnamomum aromaticum , Cinnamomum , China , Cinnamomum zeylanicum , Medicina Tradicional China
14.
Zhongguo Zhong Yao Za Zhi ; 44(19): 4152-4157, 2019 Oct.
Artículo en Zh | MEDLINE | ID: mdl-31872692

RESUMEN

Target discovery is the core of elucidating the mechanism of traditional Chinese medicine( TCM),and it is also the key to correlate the chemical composition and pharmacological action of TCM. The traditional target screening methods such as the activitybased probe profiling,affinity chromatography,and protein microarray are commonly used in the past,however,which are limited in TCM due to the complexity of small molecules existed in the herbal medicine. The label-free small molecule probe is a recently well-applied technology in the target discovery of natural products,which is characterized by discovering the small molecule-protein ligation without any structural modification at the ligands,and is therefore suitable to the complex chemical constituents in TCM. Furthermore,this method is conducted on the basis of proteome,which is advanced in the discovery of new or multiple target proteins of TCM. Owing to the potential of label-free probe in the target discovery of TCM,its analytical principle,application status,and general protocol were reviewed in this paper. The label-free probe technology is anticipated to accelerate the mechanism-uncovering of TCM.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Plantas Medicinales , Ligandos , Fitoterapia
15.
Zhongguo Zhong Yao Za Zhi ; 44(2): 314-318, 2019 Jan.
Artículo en Zh | MEDLINE | ID: mdl-30989951

RESUMEN

Nine compounds were isolated from chloroform fraction of Houttuynia cordata,and the isolates were identified as follows:( S)-5,6,6 a,7-tetrahydro-2,10-dimethoxy-4 H-dibenzo [DE,G] quinoline-1,9-diol( 1),( +)-isoboldine ß-N-oxide( 2),liriotulipiferine( 3),telitoxinone( 4),isoboldine( 5),(-)-clovane-2ß,9α-diol( 6),benzoic acid( 7),acantrifoside E( 8),and dibutyl phthalate( 9). Among them,compound 1 was new,and compounds 2-9 were reported from this species for the first time.


Asunto(s)
Medicamentos Herbarios Chinos/química , Houttuynia/química , Fitoquímicos/análisis , Extractos Vegetales/química , Cloroformo
16.
Zhongguo Zhong Yao Za Zhi ; 44(12): 2588-2593, 2019 Jun.
Artículo en Zh | MEDLINE | ID: mdl-31359728

RESUMEN

The PK-PD correlation models by using pharmacodynamics and pharmacokinetics were applied to study the material basis of Naomaitong,a clinical empirical prescription for the treatment of cerebral apoplexy,in inhibiting the death of PC12 nerve cells induced by Na_2S_2O_4 and Glu. In this experiment,PC12 cell death models induced by Na_2S_2O_4 and Glu were established respectively.With LDH lateral leakage and NO content as pharmacodynamic indexes,PK-PD model was established by SVM algorithm to evaluate the effective components of Naomaitong in inhibiting neural cell death. The results showed that the positive correlation of emodin methyl ether-8-O-ß-D-glucopyranoside,aloe emodin,chrysophanol,rhein,emodin,ginsenoside Rg1,ginsenoside Rc,3'-methoxypuerarin and ligustilide was significant,obviously improving the LDH release and NO content. The results indicated that the contribution of Radix Puerariae Lobatae Radix and Rhei Radix et Rhizoma in Naomaitong could protect the nerve cell death induced by Na_2S_2O_4 and Glu respectively. PK-PD model was used to screen the neuroprotective components in Naomaitong,revealing the possible pharmacodynamic material basis of Naomaitong in the treatment of cerebral ischemia injury.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Neuronas/citología , Fármacos Neuroprotectores/farmacología , Animales , Células PC12 , Ratas
17.
Langmuir ; 34(50): 15160-15165, 2018 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-30485107

RESUMEN

One-dimensional microscale surface-enhanced Raman scattering (SERS)-active interfaces have been intriguing as a newly emerging class of SERS interfaces compared to conventional macroscale SERS substrates. In this work, a stable surface-nanostructured single silver nanowire was fabricated. The nanostructures on the nanowire are formed by nanoscale silver crystal dots with diameters of 20-50 nm. The SERS signals of the crystal violet probe molecules adsorbed on the nanostructures are dramatically enhanced by both electromagnetic and chemical effects. The hot spots generated at the junctions of adjacent nanoscale dots yield highly efficient surface plasmon resonance. Simultaneously, the charge transfer on the atomic-scale silver cluster located at the nanostructured interface causes an enhancement similar to Raman resonance. The intensity distributions of the SERS peaks on the surface-nanostructured single nanowire are characterized by SERS mapping. It is found that, although the intensities of the SERS peaks are different, their SERS mapping images show uniform SERS enhancement distributions, whereas the noticeable SERS intensity distributions on the single smooth silver nanowire are mainly located on the two ends of the nanowire. A large number of nanoscale crystal dots along with the atomic-scale silver clusters are uniformly and densely distributed on the surface of the single roughened nanowire; these structural attributes induce a uniform and large surface plasmon resonance and charge transfer enhancements on the entire surface of the nanowire. This work indicates that the surface-nanostructured single silver nanowire, synthesized using a quite simple preparation method, performs as an excellent one-dimensional microscale SERS substrate with uniform and high enhancement characteristics, which shows high potential for applications as a new class of SERS-active substrates. Furthermore, the higher enhancement factor of the microscale SERS interfaces can be achieved by introducing other roughened nanowires to assemble a dimer and a trimer as micro-SERS substrates, which is consistent with the dark-field measurements.

18.
Anal Bioanal Chem ; 408(13): 3555-70, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26931121

RESUMEN

Proanthocyanidins (PAs) are major anti-diarrhea constituents in rhubarb, one of the frequently used traditional medicines. However, the phytochemical investigation of PAs in rhubarb was hampered by their strenuous purification and identification. In the present study, aiming to clarify the distribution of PAs in different rhubarb species, a molecular ion index was priorly established according to the structural features of B-type PAs, which led to a series of targeted discovery of oligomeric PAs in rhubarb by the HPLC-ESI-MS/MS method. Totally, 66 oligomeric PAs including 27 dimers, 29 trimers, and 10 tetramers were tentatively identified on the basis of their MS/MS spectra from 28 rhubarb samples derived from 5 Rheum species as R. palmatum, R. tanguticum, R. officinale, R. coreanum, and R. laciniatum. It is noteworthy that 6 propelargonidins, 14 prodelphinidins, and 10 procyanidin-tetramers were identified from rhubarb for the first time. The profiling comparison of these oligomeric PAs in different rhubarb samples was achieved by visualizing their abundance in a heat map, which indicated the dominant PAs in rhubarb were procyanidin-dimer and its galloylated derivatives.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Proantocianidinas/análisis , Rheum/química , Espectrometría de Masas en Tándem/métodos , Especificidad de la Especie , Espectrometría de Masa por Ionización de Electrospray/métodos
19.
J Nat Prod ; 79(7): 1834-41, 2016 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-27400231

RESUMEN

An aqueous extract of Eleutherococcus senticosus leaves exerted a beneficial effect in restoring the neurite outgrowth from Aß25-35-induced degeneration using an axonal density assay. Subsequent bioassay-guided fractionation afforded seven new oleanane-type triterpene saponins, ezoukoginosides A-G (1-7), along with nine known analogues. The structures of 1-7 were elucidated through chemical and spectroscopic approaches, and their effects on restoring the neurite outgrowth from Aß25-35-induced degeneration were investigated. The results revealed that hydrophilic oleanane-type saponins substituted with a free carboxylic acid, hydroxy, or formyl group in the aglycone, especially when the oxidation occurred at C-29, not only restrained Aß25-35-induced degeneration but also restored axonal outgrowth significantly. Compounds 2 (-COOH at C-29) and 3 (-CH2OH at C-29) showed the most potent bioactivity among the isolates.


Asunto(s)
Eleutherococcus/química , Proyección Neuronal/efectos de los fármacos , Ácido Oleanólico/aislamiento & purificación , Ácido Oleanólico/farmacología , Hojas de la Planta/química , Saponinas/aislamiento & purificación , Saponinas/farmacología , Péptidos beta-Amiloides/química , Péptidos beta-Amiloides/farmacología , Animales , Femenino , Japón , Ratones , Estructura Molecular , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Fragmentos de Péptidos/química , Fragmentos de Péptidos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Embarazo , Saponinas/química
20.
Acta Biochim Biophys Sin (Shanghai) ; 48(12): 1120-1127, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27797721

RESUMEN

Zinc finger protein X-linked (ZFX) is a key regulator of both embryonic stem cells (ESCs) and hematopoietic stem cells (HSCs), which is required for both Notch intracellular domain (NotchIC)-induced acute T-cell leukemia and MLL-AF9-induced myeloid leukemia in mouse models. However, the role of ZFX and its underlying mechanism in human leukemic cells remain unclear yet, though accumulating data have demonstrated that ZFX is aberrantly expressed in various human tumors and plays an important role. Herein, we found that ZFX was aberrantly expressed in various human leukemic cell lines and primary cells from leukemia patients compared with control cells. The silence of ZFX led to the growth suppression through either the deregulated cell cycle or the induction of apoptosis in various cells including K562, Jurkat, Namalwa, and THP-1 cells. The gene expression analysis revealed that UDP-Gal:ßGlcNAc ß 1,4-galactosyltransferase, polypeptide 1 (B4GALT1) was significantly down-regulated upon ZFX silencing, which is implicated in the response of K562 cells to the treatment of imatinib mesylate (IM). In addition, lectin blot assay showed that the galactosylation of glycoproteins in K562 cells was suppressed upon ZFX silencing. Interestingly, overexpression of B4GALT1 restored the growth and conferred drug resistance to ZFX-silenced cells. Taken together, we have demonstrated that ZFX is aberrantly expressed in multiple human leukemic cells and it modulates the growth and drug response of leukemic cells partially via B4GALT1, which suggests that ZFX is a new regulator of leukemic cells and warrants intensive investigations on this 'stemness' regulator in these deadly diseases.


Asunto(s)
Galactosiltransferasas/fisiología , Factores de Transcripción de Tipo Kruppel/fisiología , Leucemia de Células T/patología , Línea Celular Tumoral , Proliferación Celular/fisiología , Silenciador del Gen , Humanos , Factores de Transcripción de Tipo Kruppel/genética
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