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1.
Mass Spectrom Rev ; 42(5): 1772-1807, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35532212

RESUMEN

Food authentication and origin traceability are popular research topics, especially as concerns about food quality continue to increase. Mass spectrometry (MS) plays an indispensable role in food authentication and origin traceability. In this review, the applications of MS in food authentication and origin traceability by analyzing the main components and chemical fingerprints or profiles are summarized. In addition, the characteristic markers for food authentication are also reviewed, and the advantages and disadvantages of MS-based techniques for food authentication, as well as the current trends and challenges, are discussed. The fingerprinting and profiling methods, in combination with multivariate statistical analysis, are more suitable for the authentication of high-value foods, while characteristic marker-based methods are more suitable for adulteration detection. Several new techniques have been introduced to the field, such as proton transfer reaction mass spectrometry, ambient ionization mass spectrometry (AIMS), and ion mobility mass spectrometry, for the determination of food adulteration due to their fast and convenient analysis. As an important trend, the miniaturization of MS offers advantages, such as small and portable instrumentation and fast and nondestructive analysis. Moreover, many applications in food authentication are using AIMS, which can help food authentication in food inspection/field analysis. This review provides a reference and guide for food authentication and traceability based on MS.

2.
Ann Hematol ; 102(3): 529-539, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36680600

RESUMEN

Aplastic anemia (AA) is an auto-activated T cell-mediated bone marrow failure. Cyclosporine is often used to treat non-severe AA, which demonstrates a more heterogeneous condition than severe AA. The response rate to cyclosporine is only around 50% in non-severe AA. To better predict response to cyclosporine and pinpoint who is the appropriate candidate for cyclosporine, we performed phenotypic and functional T cell immune signature at single cell level by mass cytometry from 30 patients with non-severe AA. Unexpectedly, non-significant differences of T cell subsets were observed between AA and healthy control or cyclosporine-responder and non-responders. Interestingly, when screening the expression of co-inhibitory molecules, T cell trafficking mediators, and cytokines, we found an increase of cytotoxic T lymphocyte antigen 4 (CTLA-4) on T cells in response to cyclosporine and a lower level of CTLA-4 on CD8+ T cells was correlated to hematologic response. Moreover, a decreased expression of sphingosine-1-phosphate receptor 1 (S1P1) on naive T cells and a lower level of interleukin-9 (IL-9) on T helpers also predicted a better response to cyclosporine, respectively. Therefore, the T cell immune signature, especially in CTAL-4, S1P1, and IL-9, has a predictive value for response to cyclosporine. Collectively, our study implies that immune signature analysis of T cell by mass cytometry is a useful tool to make a strategic decision on cyclosporine treatment of AA.


Asunto(s)
Anemia Aplásica , Linfocitos T , Humanos , Anemia Aplásica/diagnóstico , Linfocitos T CD8-positivos/metabolismo , Antígeno CTLA-4/metabolismo , Ciclosporina , Interleucina-9/metabolismo , Linfocitos T/inmunología
3.
Phys Chem Chem Phys ; 25(7): 5627-5637, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36727641

RESUMEN

One of the challenging problems in the research field of polymer nanocomposites is how to prepare nanocomposites with high grafting density and strong ability of dispersion at the same time. For nanocomposites composed of bimodal bidisperse polymer chains and nanoparticles, the above requirements can be met by rationally adjusting the ratio of long and short polymer chains. In this study, the process of grafting bimodal bidisperse polymer chains onto the surface of nanoparticles in a grafting-to manner was investigated via computer simulation and theoretical methods. Three grafting strategies were designed: first short then long (SL) system, both short and long (Both) system and first long then short (LS) system. An abnormal phenomenon for the Both system was found by analyzing the grafting density of long and short polymer chains on the surface of nanoparticles. We speculate that the reason for this anomalous phenomenon is the "depletion effect" brought about by the long chains in the Both system. We employ the Polymer Reference Interaction Site Model (PRISM) theory to investigate this anomaly in-depth. By comparing the radial distribution function (RDF) predicted by the PRISM theory with the RDF results obtained by the molecular dynamics (MD) simulation, we found that with the increase of the number of long chains in the system, the grafting density of short polymer chains on the nanoparticle surface showed an obvious upward trend. The "depletion effect" brought by long chains was the main reason for higher short chains' grafting density of the Both system compared to the SL system. Our findings provide effective guidance for the design of nanoparticle-grafted bimodal bidisperse polymer chains and provide a theoretical basis for experimentation and production of polymer nanocomposites with better performance.

4.
Molecules ; 28(13)2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37446674

RESUMEN

The solubility of thiamine nitrate in {(methanol, acetone, isopropanol) + water} solvents will provide essential support for crystallization design and further theoretical studies. In this study, the solubility was experimentally measured over temperatures ranging from 278.15 to 313.15 K under atmospheric pressure using a dynamic method. The solubility increased with increasing temperature at a constant solvent composition. The dissolving capacity of thiamine nitrate in the three binary solvent mixtures at constant temperature in the low ratio of water ranked as water + methanol > water + acetone > water + isopropanol generally. Interestingly, in the high ratio of water systems, especially when the molar concentration of water was greater than 0.6, the dissolving capacity ranked as water + acetone > water + methanol > water + isopropanol. Additionally, the modified Apelblat equation, λh equation, van't Hoff equation and NRTL model were used to correlate the solubility data in binary mixtures. It turned out that all the selected thermodynamic models could give satisfactory results. Furthermore, the thermodynamic properties of the dissolution process of thiamine nitrate were also calculated based on the modified van't Hoff equation. The results indicate that the dissolution process of the thiamine nitrate in the selected solvents is all endothermic.


Asunto(s)
Metanol , Nitratos , Solventes/química , Metanol/química , Solubilidad , 2-Propanol/química , Acetona , Tiamina , Termodinámica , Agua/química , Temperatura
5.
Minim Invasive Ther Allied Technol ; 32(4): 153-162, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37051809

RESUMEN

BACKGROUND: Robotic camera holders can overcome the shortcomings of human assistants, such as shaking and accidental rotation in endoscopic surgery. Robotic camera holder is not affected by the operation time and surgical position and reduces the size of the team. However, there is still controversy over the practicality of robotic camera holders. MATERIAL AND METHODS: We searched PubMed, Web of Science, Embase, Cochrane Library PubMed, Embase, Cochrane Library and Web of Science. The last database search was performed on 30 April 2022. Two reviewers independently reviewed the studies. RESULTS: A total of eight studies (n = 698, 354 controls and 344 robotic camera holders) were included in our analysis. The results showed that the robotic camera holder significantly outperformed human assistants on the frequency of lens cleaning (SMD, -0.48; 95% CI, -0.90 to -0.05) and inappropriate movements (MD, -3.57; 95% CI, -4.93 to -2.21). There was no difference in total operation time (MD, 6.99; 95% CI, -2.47 to 16.72), preparation time (MD, 2.43; 95% CI, -0.32 to 5.18) or blood loss (MD, 34.47; 95% CI, -8.05 to 76.98) between the robotic camera holder and human assistant. However, the robotic camera holder was significantly slower in the core operation (MD, 5.06; 95% CI, 1.18 to 8.94), and surgeons had mixed reviews of robotic systems. CONCLUSIONS: The robotic camera holder provided the surgeon with a highly stable environment. Although the robotic camera holder will not increase the total time, it still needs to improve the core operation time. There is much room for improvement in robotic camera holders. Further development of devices with intuitive control systems and a greater range of motion will be required to accommodate more complex surgeries.


Asunto(s)
Laparoscopía , Procedimientos Quirúrgicos Robotizados , Robótica , Cirujanos , Humanos , Procedimientos Quirúrgicos Robotizados/métodos , Laparoscopía/métodos , Robótica/métodos , Tempo Operativo
6.
Crit Rev Food Sci Nutr ; : 1-25, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35880423

RESUMEN

Mycotoxins are toxic secondary metabolites generated from toxigenic fungi in the contaminated food and agro-food, which have been regarded as a serious threat to the food safety and human health. Therefore, the control of mycotoxins and toxigenic fungi contamination is of great significance and has attracted the increasing attention of researchers. As we know, nano-semiconductors have many unique properties such as large surface area, structural stability, good biocompatibility, excellent photoelectrical properties, and low cost, which have been developed and applied in many research fields. Recently, nano-semiconductors have also been promisingly applied in mitigating or controlling mycotoxins and toxigenic fungi contaminations in food and agro-food. In this review, the type, occurrence, and toxicity of main mycotoxins in food and agro-food were introduced. Then, a variety of strategies to mitigate the mycotoxin contamination based on nano-semiconductors involving mycotoxins detection, inhibition of toxigenic fungi, and mycotoxins degradation were summarized. Finally, the outlook, opportunities, and challenges have prospected in the future for the mitigation of mycotoxins and toxigenic fungi based on nano-semiconductors.

7.
J Asian Nat Prod Res ; 24(2): 179-189, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33555224

RESUMEN

In this study, a liquid chromatography-tandem multi-stage mass spectrometry (LC/MSn) method was established to characterize the metabolites of TRG in monkeys and dogs. A total of seven metabolites of TRG besides the prototype were found, which were identified as TR (M1), TRN (M2), trans-resveratrol-4'-O-glucuronide (M2'), trans-resveratrol-3-O-glucoside-4'-O-glucuronide (M3), trans-resveratrol-3-O-glucoside-5-O-glucuronide (M3'), trans-resveratrol-3-sulfate (M4) and trans-resveratrol-4'-sulfate (M4'). Additionally, the metabolic pathways of TRG in monkeys and dogs were proposed. There were also species differences of metabolism of TRG between monkeys and dogs.


Asunto(s)
Glucósidos , Animales , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Perros , Haplorrinos , Estructura Molecular , Estilbenos
8.
Glycoconj J ; 38(1): 25-33, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33411075

RESUMEN

Oviductus ranae (O.ran.) has been widely used as a tonic and a traditional animal-based Chinese medicine. O.ran. extracts have been reported to have numerous biological activities, including activities that are often associated with mammalian glycosaminoglycans such as anti-inflammatory, antiosteoperotic, and anti-asthmatic. Glycosaminoglycans are complex linear polysaccharides ubiquitous in mammals that possess a wide range of biological activities. However, their presence and possible structural characteristics within O.ran. were previously unknown. In this study, glycosaminoglycans were isolated from O.ran. and their disaccharide compositions were analyzed by liquid chromatography-ion trap/time-of-flight mass spectrometry (LC-MS-ITTOF). Heparan sulfate (HS)/heparin (HP), chondroitin sulfate (CS)/dermatan sulfate (DS) and hyaluronic acid (HA) were detected in O.ran. with varied disaccharide compositions. HS species contain highly acetylated disaccharides, and have various structures in their constituent chains. CS/DS chains also possess a heterogeneous structure with different sulfation patterns and densities. This novel structural information could help clarify the possible involvement of these polysaccharides in the biological activities of O.ran..


Asunto(s)
Glicosaminoglicanos/análisis , Glicosaminoglicanos/química , Materia Medica/química , Sulfatos de Condroitina/análisis , Cromatografía Liquida , Dermatán Sulfato/análogos & derivados , Dermatán Sulfato/análisis , Disacáridos/análisis , Disacáridos/aislamiento & purificación , Glicosaminoglicanos/aislamiento & purificación , Heparina/análisis , Heparitina Sulfato/análisis , Espectrometría de Masas/métodos , Sensibilidad y Especificidad
9.
Ann Hematol ; 100(2): 445-453, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33140135

RESUMEN

25-hydroxy vitamin D [25-(OH)D] is widely used to determine vitamin D status in clinic. The aim of our study was to evaluate the prognostic value of 25-(OH)D in extranodal NK/T cell lymphoma (ENKTL). Ninety-three (93) ENKTL patients with available serum 25-(OH)D values were enrolled in our study. Vitamin D deficiency is defined as a 25-(OH)D below 50 nmol/L (20 ng/ml). Univariate and multivariate regression analyses were performed to determine independent risk factors for progression-free survival (PFS) and overall survival (OS). Receiver operator characteristic (ROC) curves were plotted, and corresponding areas under the curves (AUC) were calculated to estimate the accuracy of PINK-E (prognostic index of natural killer lymphoma added with Epstein-Barr virus-DNA status) and 25-(OH)D deficiency in ENKTL risk-stratification. Our results suggested that the vitamin D deficiency was an independent inferior prognostic factor for both PFS [hazard ratio (HR), 2.869; 95% confidence interval (CI), 1.540 to 5.346; P = 0.003] and OS (HR, 3.204; 95% CI, 1.559 to 6.583; P = 0.006) in patients with ENKTL. Additionally, we demonstrated that adding 25-(OH)D deficiency to PINK-E score system indeed has a superior prognostic significance than PINK-E alone for PFS [AUC: 0.796 (95% CI: 0.699 to 0.872) vs. 0.759 (95% CI: 0.659 to 0.841), P = 0.020] and OS [AUC: 0.755 (95% CI: 0.655 to 0.838) vs. 0.721 (95% CI: 0.618 to 0.809), P = 0.040]. In conclusion, our study proved that 25-(OH)D deficiency was associated with inferior survival outcome of ENKTL patients.


Asunto(s)
Linfoma Extranodal de Células NK-T , Deficiencia de Vitamina D , Vitamina D/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Humanos , Linfoma Extranodal de Células NK-T/sangre , Linfoma Extranodal de Células NK-T/tratamiento farmacológico , Linfoma Extranodal de Células NK-T/mortalidad , Masculino , Persona de Mediana Edad , Tasa de Supervivencia , Vitamina D/sangre , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/tratamiento farmacológico , Deficiencia de Vitamina D/mortalidad
10.
J Fluoresc ; 31(4): 1169-1176, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34021432

RESUMEN

A new Zn(II)-bearing metal-organic framework (MOF), namely, {[Zn2(L)2(H2O)]·8H2O·DMF}n (1) has been generated via applying 4,4'-([2,3'-bipyridine]-4,6-diyl) dibenzoic acid (H2L), a pyridine-carboxylic acid ligand under the solvothermal reaction conditions. In the aqueous solution, complex 1 could be utilized as the fluorescent sensor for the simultaneous detection of Cr2O72- ion and CrO42- ion with low limits of detection and high sensitivity. It is important that this luminescent material can be regenerated quickly and the sensing ability of this luminescent material can be reused for three times. Furthermore, the assessment of the compound's application values against the Tuberculosis care was carried out and simultaneously its relevant mechanism was investigated. First of all, the bacterial burden in the lung macrophages was measured with plate micro-dilution method. Besides, the signaling pathway of JAK/STAT activation was evaluated with real time RT-PCR. Molecular docking simulation reveals that the polar oxygens are the active sites that could form binding interactions the protein.


Asunto(s)
Cromo , Estructuras Metalorgánicas , Simulación del Acoplamiento Molecular
11.
J Sci Food Agric ; 101(12): 5067-5074, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33570768

RESUMEN

BACKGROUND: Konjac glucomannan (KGM) showed a synergistic interaction with κ-carrageenan (CAR), which led to the formation of a promising compound hydrocolloid gel in the food field (such as jelly). Nevertheless, the mixed gels formed by adding KGM to CAR still displayed defects in gel strength and syneresis, and would hardly meet the quality requirements of some gel foods. However, deacetylated KGM and maltodextrin (MD) have always been used in gel foods and affect their viscosity and rheological properties. RESULTS: In our paper, different amounts of MD were first used to alter the textural properties, and the results showed that both tensile strength and elongation exhibited first an increasing and then a decreasing trend with the increasing MD proportion and achieved a maximum at a final maltodextrin proportion of 4 g kg-1 in the KGM/CAR/MD system. Based on the above results, we further explored the effects of deacetylation degree of KGM on the gel properties of mixed gel system. The results revealed that, compared to the native KGM, the partial deacetylated KGM was capable of significantly improving the tensile strength and elongation of KGM/CAR mixed gel. CONCLUSION: Our study found that the appropriate addition of MD (0.4%) and DKGM were able to alter the tensile properties of KGM/CAR mixed gel, with potential to meet the needs of consumers and further design innovative tensile gel products in the soft gel industry. © 2021 Society of Chemical Industry.


Asunto(s)
Amorphophallus/química , Carragenina/química , Mananos/química , Extractos Vegetales/química , Coloides/química , Geles/química , Polisacáridos/química , Reología , Resistencia a la Tracción , Viscosidad
12.
Pharmazie ; 76(2): 55-60, 2021 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-33714280

RESUMEN

Ferulic acid, a hydroxyl derivative extracted from plants, is abundant in free state in seeds and leaves, or covalently linked with cell wall polysaccharides, lignin and different polymers. It has various pharmacological activities, including antioxidant and anti-inflammatory effects, regulates immunity, protects the cardiovascular system, and contributes to the prevention of tumors and diabetes. The protective effect on cardiovascular system is the most valuable one in view of clinical application. Here, we are reviewing the research progress concerning the pharmacological effects of ferulic acid and its derivatives on cardiovascular diseases in the past five years, mainly focusing on mechanisms of action and clinical application. This should provide guidance for clinical applications of ferulic acid and its derivatives in the treatment of cardiovascular diseases.


Asunto(s)
Enfermedades Cardiovasculares/tratamiento farmacológico , Ácidos Cumáricos/farmacología , Animales , Humanos , Extractos Vegetales , Plantas/química
13.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(4): 513-520, 2020 Aug 30.
Artículo en Zh | MEDLINE | ID: mdl-32895104

RESUMEN

Objective To compare the short-and long-term effect of two minimal invasive surgical therapies including keyhole approach endoscopic surgery(KAES)and stereotactic aspiration plus urokinase(SAU)in treating basal ganglia hypertensive intracerebral hemorrhage(hICH). Methods The clinical data of 117 hICH patients(63 received KAES and 54 received SAU)were retrospectively analyzed.The operation time,blood loss during surgery,and drainage time were compared between two groups.The residual hematoma volume,hematoma clearance rate(HCR),Glasgow coma scale(GCS)score,and National Institute of Health Stroke Scale(NIHSS)score were recorded at baseline and in the ultra-early stage,early stage,and sub-early stage after surgery.The 30-day mortality and serious adverse events were assessed and the 6-month modified Rankin scale(mRS)score was rated.Results Baseline data showed no significant difference between these two groups.Compared with the SAU group,the KAES group had significantly longer operation time,more intraoperative blood loss,and shorter drainage time(all P<0.001).In the ultra-early stage after surgery,HCR was significantly higher in the KAES group(P<0.001),whereas in the early and sub-early stage,HCR showed no significant differences(all P>0.05).In the ultra-early and early stage,the GCS and NIHSS scores showed no significant differences between two groups(all P>0.05),whereas in the sub-early stage,the NIHSS score was better in the SAU group(P=0.034).The 30-day mortality and incidences of serious adverse events showed no significant difference(all P>0.05).The good recovery(mRS≤3)at 6-months follow-up showed no significant difference between the two groups(P=0.413).Conclusions Both KAES and SAU are safe and effective in treating basal ganglia hICH.In the ultra-early stage after surgery,KAES achieves better residual hematoma volume and HCR,and patients undergoing SAU quickly catch up.The short-and long-term effectiveness of SAU is comparable or even superior to KAES.


Asunto(s)
Hemorragia Intracraneal Hipertensiva , Ganglios Basales , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Activador de Plasminógeno de Tipo Uroquinasa
15.
Nano Lett ; 18(7): 4200-4205, 2018 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-29911870

RESUMEN

Through-bond conjugated molecules are the major frameworks for traditional molecular wires, while through-space conjugated units are rarely utilized and studied although they have shown unique conducting potential. Herein, we present novel single-molecule wires built on through-space conjugated hexaphenylbenzene. Their conductance, measured by the scanning tunneling microscopy based break-junction technique, increases with the improvement of through-space conjugation and finally reaches a remarkable value (12.28 nS) which greatly exceeds that of conventional through-bond conjugated counterpart (2.45 nS). The multichannel conducting model by integrating through-space and through-bond conjugations could be a promising strategy for the further design of robust single-molecule wires with advanced conductance and stability.

16.
J Nanosci Nanotechnol ; 18(3): 2085-2088, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29448718

RESUMEN

We have measured the conductance of pyrazine molecular junction contacting with Cu and Ag electrodes by using an electrochemical jump-to-contact based scanning tunneling microscopy break junction (ECSTM-BJ). While conductance values of 10-2.8 and 10-3.7 G0 are measured for pyrazineCu electrode, 10-2.1 and 10-3.3 G0 are found for pyrazine-Ag contact. The result shows that the conductance of pyrazine with Ag electrode is larger than that with Cu electrode, which can contribute to the different efficiency of electron transport along the molecular junction between Ag and Cu electrodes. The current work shows the important role for the electrode material in electron transport.

17.
Molecules ; 23(5)2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29762486

RESUMEN

Chemical composition of secondary metabolites is of great importance for quality control of agricultural products. Black sesame seeds are significantly more expensive than white sesame seeds, because it is thought that black sesame seeds are more beneficial to human health than white sesame seeds. However, the differences in nutrient composition between black sesame seeds and white sesame seeds are still unknown. The current study examined the levels of different metabolites in black and white sesame seeds via the use of a novel metabolomics strategy. Using widely targeted metabolomics data, we obtained the structure and content of 557 metabolites, out of which 217 metabolites were identified, and discovered 30 metabolic pathways activated by the secondary metabolites in both black and white sesame seeds. Our results demonstrated that the main pathways that were differentially activated included: phenylpropanoid biosynthesis, tyrosine metabolism, and riboflavin metabolism. More importantly, the biomarkers that were significantly different between black seeds and white sesame seeds are highly related to the functions recorded in traditional Chinese medicine. The results of this study may serve as a new theoretical reference for breeding experts to promote the genetic improvement of sesame seeds, and therefore the cultivation of higher quality sesame varieties.


Asunto(s)
Metaboloma , Metabolómica , Evaluación Nutricional , Sesamum/anatomía & histología , Sesamum/metabolismo , Cromatografía Liquida , Humanos , Medicina Tradicional China , Metabolómica/métodos , Semillas/anatomía & histología , Semillas/metabolismo , Espectrometría de Masas en Tándem
18.
Molecules ; 23(2)2018 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-29370131

RESUMEN

Adulteration of edible oils has attracted attention from more researchers and consumers in recent years. Complex multispecies adulteration is a commonly used strategy to mask the traditional adulteration detection methods. Most of the researchers were only concerned about single targeted adulterants, however, it was difficult to identify complex multispecies adulteration or untargeted adulterants. To detect adulteration of edible oil, identification of characteristic markers of adulterants was proposed to be an effective method, which could provide a solution for multispecies adulteration detection. In this study, a simple method of multispecies adulteration detection for camellia oil (adulterated with soybean oil, peanut oil, rapeseed oil) was developed by quantifying chemical markers including four isoflavones, trans-resveratrol and sinapic acid, which used liquid chromatography tandem mass spectrometry (LC-MS/MS) combined with solid phase extraction (SPE). In commercial camellia oil, only two of them were detected of daidzin with the average content of 0.06 ng/g while other markers were absent. The developed method was highly sensitive as the limits of detection (LODs) ranged from 0.02 ng/mL to 0.16 ng/mL and the mean recoveries ranged from 79.7% to 113.5%, indicating that this method was reliable to detect potential characteristic markers in edible oils. Six target compounds for pure camellia oils, soybean oils, peanut oils and rapeseed oils had been analyzed to get the results. The validation results indicated that this simple and rapid method was successfully employed to determine multispecies adulteration of camellia oil adulterated with soybean, peanut and rapeseed oils.


Asunto(s)
Camellia/química , Fitoquímicos/análisis , Fitoquímicos/química , Aceites de Plantas/análisis , Aceites de Plantas/química , Cromatografía Liquida/métodos , Contaminación de Alimentos , Límite de Detección , Espectrometría de Masas/métodos , Fitoquímicos/aislamiento & purificación , Aceites de Plantas/aislamiento & purificación , Reproducibilidad de los Resultados , Extracción en Fase Sólida
19.
Development ; 141(24): 4697-709, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25468938

RESUMEN

The balance between self-renewal and differentiation of adult neural stem cells (aNSCs) is essential for the maintenance of the aNSC reservoir and the continuous supply of new neurons, but how this balance is fine-tuned in the adult brain is not fully understood. Here, we investigate the role of SIRT1, an important metabolic sensor and epigenetic repressor, in regulating adult hippocampal neurogenesis in mice. We found that there was an increase in SIRT1 expression during aNSC differentiation. In Sirt1 knockout (KO) mice, as well as in brain-specific and inducible stem cell-specific conditional KO mice, the proliferation and self-renewal rates of aNSCs in vivo were elevated. Proliferation and self-renewal rates of aNSCs and adult neural progenitor cells (aNPCs) were also elevated in neurospheres derived from Sirt1 KO mice and were suppressed by the SIRT1 agonist resveratrol in neurospheres from wild-type mice. In cultured neurospheres, 2-deoxy-D-glucose-induced metabolic stress suppressed aNSC/aNPC proliferation, and this effect was mediated in part by elevating SIRT1 activity. Microarray and biochemical analysis of neurospheres suggested an inhibitory effect of SIRT1 on Notch signaling in aNSCs/aNPCs. Inhibition of Notch signaling by a γ-secretase inhibitor also largely abolished the increased aNSC/aNPC proliferation caused by Sirt1 deletion. Together, these findings indicate that SIRT1 is an important regulator of aNSC/aNPC self-renewal and a potential mediator of the effect of metabolic changes.


Asunto(s)
Células Madre Adultas/fisiología , Proliferación Celular/fisiología , Giro Dentado/citología , Regulación de la Expresión Génica/fisiología , Células-Madre Neurales/fisiología , Sirtuina 1/metabolismo , Células Madre Adultas/metabolismo , Animales , Western Blotting , Bromodesoxiuridina , Proliferación Celular/efectos de los fármacos , Desoxiglucosa/efectos adversos , Fluorescencia , Regulación de la Expresión Génica/efectos de los fármacos , Ratones , Ratones Noqueados , Análisis por Micromatrices , Microscopía Confocal , Células-Madre Neurales/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/fisiología , Sirtuina 1/genética , Estadísticas no Paramétricas , Tamoxifeno
20.
Nanotechnology ; 28(44): 445502, 2017 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-28825406

RESUMEN

Flexible electronic skin has stimulated significant interest due to its widespread applications in the fields of human-machine interactivity, smart robots and health monitoring. As typical elements of electrical skin, the fabrication process of most pressure sensors combined nanomaterials and PDMS films are redundant, expensive and complicated, and their unknown biological toxicity could not be widely used in electronic skin. Hence, we report a novel, cost-effective and antibacterial approach to immobilizing silver nanoparticles into-electrospun Na-alginate nanofibers. Due to the unique role of carboxyl and hydroxyl groups in Na-alginate, the silver nanopaticles with 30 nm size in diameter were uniformly distributed inside and outside the alginate nanofibers, which obtained pressure sensor shows stable response, including an ultralow detection limited (1 pa) and high durability (>1000 cycles). Notably, the pressure sensor fabricated by these Ag/alginate nanofibers could not only follow human respiration but also accurately distinguish words like 'Nano' and 'Perfect' spoke by a tester. Interestingly, the pixelated sensor arrays based on these Ag/alginate nanofibers could monitor distribution of objects and reflect their weight by measuring the different current values. Moreover, these Ag/alginate nanofibers exhibit great antibacterial activity, implying the great potential application in artificial electronic skin.

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