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1.
Breast Cancer Res Treat ; 201(1): 27-41, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37311933

RESUMEN

Neoadjuvant chemotherapy (NCT) is the standard treatment for patients with locally advanced breast cancer (LABC). The predictive value of heterogeneous circulating tumor cells (CTCs) in NCT response has not been determined. All patients were staged as LABC, and blood samples were collected at the time of biopsy, and after the first and eighth NCT courses. Patients were divided into High responders (High-R) and Low responders (Low-R) according to Miller-Payne system and changes in Ki-67 levels after NCT treatment. A novel SE-i·FISH strategy was applied to detect CTCs. Heterogeneities were successfully analyzed in patients undergoing NCT. Total CTCs increased continuously and were higher in Low-R group, while in High-R group, CTCs increased slightly during NCT before returning to baseline levels. Triploid and tetraploid chromosome 8 increased in Low-R but not High-R group. The number of small CTCs in Low-R group increased significantly until the last sample, however, remained constant in High-R group. The patients with more CTCs had shorter PFS and OS than those with less CTCs after the eighth course of NCT. Total CTCs following NCT could predict patients' responses. More detailed characterizations of CTC blood profiles may improve predictive capacity and treatments of LABC.


Asunto(s)
Neoplasias de la Mama , Células Neoplásicas Circulantes , Humanos , Femenino , Neoplasias de la Mama/patología , Células Neoplásicas Circulantes/patología , Terapia Neoadyuvante , Biomarcadores de Tumor , Pronóstico
2.
Environ Geochem Health ; 45(3): 1027-1044, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35978258

RESUMEN

The PM2.5-bounded elements were measured in outdoor and indoor from two urban middle schools in Xi'an. The PM2.5 mass was from 42.4 to 283.7 µg/m3 with bounded element from 3.4 to 41.7 µg/m3. Both the particle mass and the bounded elements displayed higher levels compared with previous studies in school environments. The most abundant elements were Ca, K, Fe, S, Zn and Cl both indoor and outdoor in two schools, which accounted for about 90% of the total elements. Strong correlations between indoor and outdoor were obtained along with relative effect from students' and teachers' activities on the indoor distributions between workdays and weekends. There had different indoor/outdoor (I/O) distributions for the two schools. It revealed the main outdoor sources for elements in JT and predominance of indoor sources in HT. The principal component analysis investigated main sources of elements in this study were coal combustion, geogenic dust and industrial emission, even though there displayed differences in the two school classrooms. The health risk assessment showed that the cancer risk for Ni and Pb was below the safe value while As and Cr might pose acceptable potential threat to both students' and teachers' health. The total non-cancer risks of accumulative multi-metals in JT exhibited to be higher than 1, indicating that there existed the potential non-carcinogenic health risks of exposure metals.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Oligoelementos , Humanos , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Oligoelementos/análisis , Polvo/análisis , Medición de Riesgo , Instituciones Académicas , China , Monitoreo del Ambiente , Material Particulado/análisis
3.
Environ Geochem Health ; 45(12): 9639-9652, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37787830

RESUMEN

Fine particulate matter (PM2.5) has health effects that may depend on its sources and chemical composition. In this study, characteristics of PM2.5 chemical composition and health risk assessment from Songyuan, China, were investigated during day and night in indoor and outdoor from February 4 to 19, 2021. Relative high concentrations of PM2.5 were obtained in indoor environment than outdoor, with 503.95 ± 209.62 µg/m3 during the day and 357.52 ± 232.81 µg/m3 at night for the indoor environment. Relatively high total carbon, organic carbons, elemental carbons, polycyclic aromatic hydrocarbons (PAHs), and oxygenated polycyclic aromatic hydrocarbons (OPAHs) were obtained in indoor environment. However, the average concentrations of PAHs were higher during night (73.57 ± 43.09 ng/m3) in indoor and OPAHs during day (6.027 ± 2.960 ng/m3) in outdoor. They had different I/O distributions of these compounds during day and night. Indeno(1,2,3-cd) pyrene was the dominant PAHs, and benzanthrone was the dominant OPAHs; this is different with the previous studies. The high indoor/outdoor ratios showed the indoor coal and biomass burning greatly affect the indoor pollutants. Average ILCR health risk assessment for PAHs was all higher than 10-6 for different age gender, suggesting there has potential cancer risk existed for populations living in the rural coal and biomass burning area Songyuan, China.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Hidrocarburos Policíclicos Aromáticos , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Carbón Mineral/análisis , Biomasa , Material Particulado/análisis , China , Hidrocarburos Policíclicos Aromáticos/toxicidad , Hidrocarburos Policíclicos Aromáticos/análisis , Medición de Riesgo , Contaminación del Aire Interior/análisis
4.
Angew Chem Int Ed Engl ; 62(42): e202306901, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37302981

RESUMEN

The sluggish sulfur redox kinetics and shuttle effect of lithium polysulfides (LiPSs) are recognized as the main obstacles to the practical applications of the lithium-sulfur (Li-S) batteries. Accelerated conversion by catalysis can mitigate these issues, leading to enhanced Li-S performance. However, a catalyst with single active site cannot simultaneously accelerate multiple LiPSs conversion. Herein, we developed a novel dual-defect (missing linker and missing cluster defects) metal-organic framework (MOF) as a new type of catalyst to achieve synergistic catalysis for the multi-step conversion reaction of LiPSs. Electrochemical tests and first-principle density functional theory (DFT) calculations revealed that different defects can realize targeted acceleration of stepwise reaction kinetics for LiPSs. Specifically, the missing linker defects can selectively accelerate the conversion of S8 →Li2 S4 , while the missing cluster defects can catalyze the reaction of Li2 S4 →Li2 S, so as to effectively inhibit the shuttle effect. Hence, the Li-S battery with an electrolyte to sulfur (E/S) ratio of 8.9 mL g-1 delivers a capacity of 1087 mAh g-1 at 0.2 C after 100 cycles. Even at high sulfur loading of 12.9 mg cm-2 and E/S=3.9 mL g-1 , an areal capacity of 10.4 mAh cm-2 for 45 cycles can still be obtained.

5.
Int J Clin Oncol ; 27(5): 889-898, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35122586

RESUMEN

BACKGROUND: Circulating tumor cells (CTCs) have been shown to be associated with the response to neoadjuvant chemotherapy (NCT) and the prognosis of locally advanced breast cancer (LABC) patients. Our study aimed to investigate whether the change of CTC status during NCT could serve as a supplement to the Response Evaluation Criteria in Solid Tumors (RECIST) in the treatment and evaluation of LABC patients. METHODS: 6 ml of blood samples were collected before NCT, after the first cycle of NCT and after the completion of NCT, respectively. According to the change of CTC number during NCT, the patients were divided into "CTC low-response (low-R)" group and "CTC high-response (high-R)" group. Survival data of each group of patients were obtained through long-term follow-up. RESULTS: A total of 35 patients diagnosed with LABC were enrolled. The median follow-up for distant metastasis was 27 months (range 7-36 months). There was no significant difference in distant metastasis-free survival (DMFS) between PR/CR group and PD/SD group (P = 0.0914), while CTC low-R group had a worse DMFS than CTC high-R group (P = 0.0199). In PR/CR subgroup, patients with CTC low-R showed a lower DMFS compared with those with CTC high-R (P = 0.0159). However, in PD/SD subgroup, there was no significant difference in DMFS between CTC low-R and CTC high-R group (P = 0.7521). In terms of assessing response to NCT, CTC change or RECIST classification alone had an AUC of 0.533 (95% CI 0.277-0.790) and 0.700 (95% CI 0.611-0.789), respectively. When combining the two, the AUC slightly increased to 0.713 (95% CI 0.532-0.895). CONCLUSION: The change of CTC number during NCT has a potential to serve as a supplement to RECIST in the assessment of NCT efficacy and the prognosis of LABC patients.


Asunto(s)
Neoplasias de la Mama , Células Neoplásicas Circulantes , Biomarcadores de Tumor , Neoplasias de la Mama/patología , Femenino , Humanos , Terapia Neoadyuvante , Células Neoplásicas Circulantes/patología , Pronóstico , Criterios de Evaluación de Respuesta en Tumores Sólidos
6.
Molecules ; 27(21)2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36364417

RESUMEN

The comprehensive balance of the mechanical, interfacial, and environmental requirements of waterborne polyurethane (WPU) has proved challenging, but crucial in the specific application as the binder for high-performance polymer fiber composites. In this work, a multi-step chain extension (MCE) method was demonstrated using three kinds of small extenders and one kind of macro-chain extender (CE) for different chain extension steps. One dihydroxyl blocked small molecular urea (1,3-dimethylolurea, DMU) was applied as one of the CEs and, through the hybrid macrodiol/diamine systems of polyether, polyester, and polysiloxane, the WPU was developed by the step-by-step optimization on each chain extending reaction via the characterization on the H-bonding association, microphase separation, and mechanical properties. The best performance was achieved when the ratio of polyether/polyester was controlled at 6:4, while 2% of DMU and 1% of polysiloxane diamine was incorporated in the third and fourth chain extension steps, respectively. Under the condition, the WPU exhibited not only excellent tensile strength of 30 MPa, elongation of break of about 1300%, and hydrophobicity indicated by the water contact angle of 98°, but also effective interfacial adhesion to para-aramid fabrics. The peeling strength of the joint based on the polysiloxane incorporated WPU after four steps of chain extension was 430% higher than that prepared through only two steps of chain extension. Moreover, about 44% of the peeling strength was sustained after the joint had been boiling for 40 min in water, suggesting the potential application for high-performance fabric composites.

7.
J Cell Biochem ; 121(10): 4142-4153, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32048761

RESUMEN

Receptor tyrosine kinase-like orphan receptor 2 (ROR2) is a tyrosine-protein kinase receptor highly implicated in the growth plate and cartilage development, which may be involved in epithelial-mesenchymal transition (EMT) in breast cancer (BC) cells. Although ROR2 is known to promote the migration of BC cells, the detailed mechanism of this event is still not clear. Here, we found that ROR2 expression was significantly increased in BC lymphatic metastatic tissue as well as BC samples compared to normal adjacent breast tissues. A higher expression of ROR2 in MDA-MB-231 and a lower expression of ROR2 in MCF-7 cells were observed. MDA-MB-231-siROR2 cells with ROR2 knockdown inhibited MDA-MB-231 cell invasion, migration, and clonal formation, while MCF-7-OvROR2 cells with overexpression showed the opposite results. The underlying mechanisms involved in ROR2-induced EMT in MDA-MB-231 and MCF-7 cells were further investigated. ROR2 may activate EMT progression in BC cells by altering MAPK kinase 3/6 (MKK3/6) expression. The expressions of transforming growth factor-ß, matrix metalloproteinase-2 (MMP-2), and MMP-9, which were related to tumor cell invasion activities, were notably increased in MCF-7-OvROR2 cells. The EMT markers, including snail, N-cadherin, tissue inhibitor of metalloproteinases-1, and vimentin, were significantly upregulated in MCF-7-OvROR2 cells. On the contrary, E-cadherin was obviously reduced expressed in MCF-7-OvROR2 cells. ROR2 may regulate the malignant phenotype of BC cells possibly via activation of mitogen-activated protein kinase (MAPK)/p38 signaling pathway. Collectively, ROR2 promotes BC carcinogenesis by mediating the MAPK/p38 pathway, which is independent of Wnt5α.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Transición Epitelial-Mesenquimal/genética , Sistema de Señalización de MAP Quinasas/genética , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Antígenos CD/metabolismo , Cadherinas/metabolismo , Carcinogénesis/genética , Movimiento Celular/genética , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Células MCF-7 , Invasividad Neoplásica/genética , Fenotipo , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/genética , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Transfección , Vimentina/metabolismo , Proteína Wnt-5a/metabolismo
8.
Anal Chem ; 92(1): 991-998, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31829556

RESUMEN

Glycosylation is an important post-translational modification of proteins, and abnormal glycosylation is involved in a variety of diseases. Accurate and rapid profiling of N-glycans by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) is still technically challenging and hampered mainly by mass drift of instrument, manual identification of spectrum peaks, and poor cocrystallization with traditional matrices besides low ionization efficiency of analytes. In the present study, a parallel on-target derivatization strategy (POTDS), on the basis of two rationally combined matrices, i.e., 3-hydrazinobenzoic acid plus DHB (DHB/3HBA) and quinoline-3-carbohydrazide plus DHB (DHB/Q3CH), was proposed for mass calibration and rapid detection of reducing N-glycans. Both DHB/3HBA and DHB/Q3CH show high derivatization efficiency and can improve the ionization efficiency of reducing N-glycans significantly. For mass calibration, in combination with dextrans, DHB/3HBA and DHB/Q3CH prove to be highly sensitive matrices facilitating both MS and MS2 calibration for N-glycans in dual polarities. For rapid identification, the regular mass difference observed for each N-glycan labeled with Q3CH and 3HBA respectively can eliminate the occurrence of false positives and promote automated identification of N-glycans in complex samples. For relative quantitation, the acid-base pair of DHB/Q3CH generates a concentrated cocrystallization of glycan-matrix mixtures at the edge of the droplet uniformly, exhibiting good linearity (R2 > 0.998) and accuracy (RSD ≤ 10%). Furthermore, the established POTDS was successfully utilized to assess N-glycans of serum from HCC patients, revealing potential for biomarker discovery in clinical practice.


Asunto(s)
Polisacáridos/sangre , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Benzoatos/síntesis química , Benzoatos/química , Carcinoma Hepatocelular/sangre , Humanos , Hidrazinas/síntesis química , Hidrazinas/química , Límite de Detección , Neoplasias Hepáticas/sangre , Polisacáridos/química , Quinolinas/síntesis química , Quinolinas/química
9.
Immunity ; 34(3): 385-95, 2011 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-21376641

RESUMEN

Myeloid-derived suppressor cells (MDSCs) bear characteristics of precursors for both M1 and M2 macrophages. The molecular mechanism underlying the differentiation into M1 and M2 macrophages and the relationship of this differentiation to antitumor responses remains largely undefined. Herein, we investigate the potential function of paired immunoglobulin-like receptor B (PIR-B), also known as leukocyte immunoglobulin-like receptor subfamily B member 3 (LILRB3) in MDSC differentiation, and its role in tumor-induced immunity. Our studies indicated that MDSCs genetically ablated for PIR-B (Lilrb3(-/-)) underwent a specific transition to M1-like cells when entering the periphery from bone marrow, resulting in decreased suppressive function, regulatory T cell activation activity, primary tumor growth, and lung metastases. Activation of Toll-like receptor (TLR), signal transducers, and activators of transcription 1 (STAT1), and nuclear factor-kappa B (NF-κB) signaling in Lilrb3(-/-) MDSC promoted the acquisition of M1 phenotype. Inhibition of the PIR-B signaling pathway promoted MDSC differentiation into M1 macrophages.


Asunto(s)
Células Mieloides/inmunología , Receptores Inmunológicos/inmunología , Animales , Linfocitos B/inmunología , Western Blotting , Células Cultivadas , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Modelos Inmunológicos , Receptores Inmunológicos/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T Reguladores/inmunología
10.
J Org Chem ; 85(6): 4324-4334, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-32043358

RESUMEN

Evaluation of the hemilability of hybrid ligands provides a key to understand the metal-ligand cooperation in transition metal catalysis. Here, we design and synthesize a type of RuII complexes based on the hemilability of N-heterocyclic carbenes (NHCs), pyridine, and pyrazole, to compare their activity with other reported Ru catalysts in benzylic C-H oxidation. The RuII catalysts showed ultrastrong catalytic activity in water at room temperature and achieved a turnover frequency (TOF) of 114 h-1, which is the highest TOF value ever reported for Ru-catalyzed benzylic C-H oxidation. The addition of tridentate hybrid ligands in the Ru central position has two beneficial effects: NHCs with a stronger donor ability stabilize the Ru center; however, nitrogen ligands with a relatively weaker donor ability release from the Ru center, so that they induce a reaction. UV-vis, high-resolution electrospray ionization mass spectrometry (ESI-MS), electron paramagnetic resonance (EPR) spectrometry, the trapping of radicals, and the density functional theory calculations (DFT) suggested that a cation catalyst L-RuII-tBuO2H is formed via the reaction between starting RuII catalysts and tert-butyl hydroperoxide, which further undergoes a cleavage of the O-O bond to generate a radical and a cation L-RuIII-OH active intermediate.

11.
J Immunol ; 201(6): 1727-1734, 2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-30068593

RESUMEN

Glatiramer acetate (GA; Copaxone) is a copolymer therapeutic that is approved by the Food and Drug Administration for the relapsing-remitting form of multiple sclerosis. Despite an unclear mechanism of action, studies have shown that GA promotes protective Th2 immunity and stimulates release of cytokines that suppress autoimmunity. In this study, we demonstrate that GA interacts with murine paired Ig-like receptor B (PIR-B) on myeloid-derived suppressor cells and suppresses the STAT1/NF-κB pathways while promoting IL-10/TGF-ß cytokine release. In inflammatory bowel disease models, GA enhanced myeloid-derived suppressor cell-dependent CD4+ regulatory T cell generation while reducing proinflammatory cytokine secretion. Human monocyte-derived macrophages responded to GA by reducing TNF-α production and promoting CD163 expression typical of alternative maturation despite the presence of GM-CSF. Furthermore, GA competitively interacts with leukocyte Ig-like receptors B (LILRBs), the human orthologs of PIR-B. Because GA limited proinflammatory activation of myeloid cells, therapeutics that target LILRBs represent novel treatment modalities for autoimmune indications.


Asunto(s)
Antígenos CD/inmunología , Acetato de Glatiramer/farmacología , Células Supresoras de Origen Mieloide/inmunología , Receptores Inmunológicos/inmunología , Animales , Antígenos CD/genética , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/genética , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/patología , Citocinas/genética , Citocinas/inmunología , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Células Supresoras de Origen Mieloide/patología , FN-kappa B/genética , FN-kappa B/inmunología , Receptores Inmunológicos/genética , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/patología , Células Th2/inmunología , Células Th2/patología
12.
Anal Chem ; 91(14): 9251-9258, 2019 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-31192583

RESUMEN

Qualitative and quantitative analysis of N-glycans by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is hampered mainly by the low ionization efficiency of analytes and their poor cocrystallization with traditional organic acid matrices. In the present study, a combination strategy of reactive and catalytic matrices (CSRCM) was proposed for the on-target derivatization and detection of reducing N-glycans: a novel reactive matrix, i.e., 2,5-dihydroxybenzohydrazide (DHBH), having a skeleton structure similar to that of DHB, was designed and synthesized, and this reactive matrix was mixed with catalytic matrix DHB to form a rationally combinatorial matrix (DHB/DHBH). Qualitatively, DHB/DHBH could improve the ionization efficiency of reducing carbohydrates significantly. Quantitatively, the acid-base chemistry of DHB/DHBH leads to a uniform cocrystallization of analytes-matrix mixtures. Consequently, CSRCM provides accurate quantitation for N-glycans with high derivatization efficiency and good linearity (R2 > 0.99) within 2 orders of magnitude on the basis of an internal standard method. Furthermore, the CSRCM was successfully applied to evaluating N-glycan in serum samples of colorectal cancer patients, thus showing potential in clinical applications for biomarker discovery.


Asunto(s)
Gentisatos/química , Hidrazinas/química , Polisacáridos/sangre , Catálisis , Ácidos Cumáricos/química , Humanos , Límite de Detección , Polisacáridos/química , Reproducibilidad de los Resultados , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos
13.
Analyst ; 144(7): 2284-2290, 2019 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-30816382

RESUMEN

Here, we found that Thioflavin T (ThT) could specifically bind with a G-GGG unit (named as "Guanine Island") in double stranded DNA (ds-DNA). Through stacking with G base via hydrogen bonds, the rotation of ThT was restricted and concurrently its planarization was enforced. Such a binding mode produced a significantly enhanced ThT fluorescence. Based on this discovery, with ThT as a lighting-up probe for "Guanine Island" in ds-DNA, the fluorescent detection of single-nucleotide mutation (C mutation) was investigated. With C base in target DNA mutating to G, A or T and further hybridizing with a probe DNA containing a GGG unit at the mutated point, ds-DNA including G-GGG, A-GGG or T-GGG islands was formed, respectively. After binding with ThT, C mutation was clearly recognized. With C mutating to G as an example, the detection limit was as low as 3 nM. Importantly, the developed assay could be applied to recognize C mutating to G in a DNA sequence related to dilated cardiomyopathy for diluted human serum. As a sensing unit ("Guanine Island" in ds-DNA lighting up ThT), it is expected to be applied for various biological or environmental systems.


Asunto(s)
Benzotiazoles/metabolismo , ADN/genética , ADN/metabolismo , Colorantes Fluorescentes/metabolismo , Guanina , Polimorfismo de Nucleótido Simple , Secuencia de Bases , Mercurio/análisis , Mercurio/química , Mercurio/toxicidad
14.
J Sep Sci ; 42(9): 1757-1767, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30811846

RESUMEN

In the present work, three hydrophilic ionic liquids based on the combination between imidazolium cations attached with ethylene glycol polymers of various lengths and hexafluorophosphate anion were designed and synthesized for the separation of polysaccharides. By employing dextran 100 kDa as model compound, the effects of ionic liquid content, solvent/anti-solvent volume, and temperature on its recovery efficiency were investigated systematically. The ability of these ionic liquids to precipitate dextran 100 kDa, increases with the elongation of ethylene glycol polymer chain. The established ionic liquid-based precipitation system was successfully applied to selectively precipitate polysaccharides from water extracts of three traditional Chinese medicines and the precipitation could be achieved in about 15 min. In addition, the different precipitation responses of acidic, neutral, and basic polysaccharides in the ionic liquid-based precipitation system and theoretical calculations both suggested that the selective precipitation of polysaccharides was probably mediated by interaction between ionic liquids and polysaccharides. The proposed strategy facilitated the isolation and purification of polysaccharides and may trigger a novel application of ionic liquids in carbohydrate research.


Asunto(s)
Fraccionamiento Químico/métodos , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales/química , Polisacáridos/aislamiento & purificación , Precipitación Química , Dextranos/química , Dextranos/aislamiento & purificación , Glicol de Etileno/química , Líquidos Iónicos/química , Extractos Vegetales/química , Polisacáridos/química , Temperatura
15.
MAGMA ; 32(1): 15-23, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29948237

RESUMEN

OBJECTIVE: Improve 19F magnetic resonance imaging uniformity of perfluorocarbon (PFC)-labeled cells by using a secondary inductive resonator tuned to 287 MHz to enhance the induced radio frequency (RF) magnetic field (B1) at 7.05 T. MATERIALS AND METHODS: Following Faraday's induction law, the sign of induced B1 made by the secondary resonator can be changed depending on the tuning of the resonator. A secondary resonator located on the opposite side of the phantom of the 19F surface coil can be shown to enhance or subtract the induced B1 field, depending upon its tuning. RESULTS: The numerical simulation results of rotating transmit B1 magnitude (|B 1 + |) and corresponding experimental 19F images were compared without and with the secondary resonator. With the secondary resonator tuned to 287 MHz, improvements of |B 1 + | and 19F image uniformity were demonstrated. The use of the secondary resonator improved our ability to visualize transplanted cell location non-invasively over a period of 6 weeks. CONCLUSION: The secondary resonator tuned to enhance the induced B1 results in improved image uniformity in a pre-clinical application, enabling cell tracking of PFC-labeled cells with the secondary resonator.


Asunto(s)
Rastreo Celular/métodos , Imagen por Resonancia Magnética con Fluor-19 , Flúor/química , Campos Magnéticos , Trasplante de Células Madre , Animales , Diseño de Equipo , Fluorocarburos , Ratones , Modelos Teóricos , Fantasmas de Imagen , Ondas de Radio , Relación Señal-Ruido
16.
Cytotherapy ; 20(12): 1472-1485, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30523789

RESUMEN

Neural stem cells (NSCs) isolated from a variety of sources are being developed as cellular therapies aimed at treating neurodegenerative diseases. During NSC culture and expansion it is important the cells do not differentiate prematurely because this may have an unfavorable effect on product quality and yield. In our study, we evaluated the use of Notch and Sox2 as markers for undifferentiated human and mouse NSCs. The expression of Notch2 and Sox2 during extensive-passage, low-oxygen culture and differentiation conditions were analyzed to confirm that the presence of these signature proteins directly correlates with the ability of NSCs to form new neurospheres and differentiate into multiple cell types. Using expression of Notch1, Notch2 and Sox2 as a reference, we then used flow cytometry to identify a specific morphological profile for undifferentiated murine and human NSCs. Our studies show that Notch and Sox2 expression, along with flow cytometry analysis, can be used to monitor the differentiation status of NSCs grown in culture for use in cellular therapies.


Asunto(s)
Diferenciación Celular/fisiología , Células-Madre Neurales/citología , Receptor Notch2/metabolismo , Factores de Transcripción SOXB1/metabolismo , Animales , Biomarcadores/metabolismo , Células Cultivadas , Citometría de Flujo , Regulación de la Expresión Génica , Proteínas Fluorescentes Verdes/genética , Humanos , Ratones , Ratones Transgénicos , Células-Madre Neurales/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptor Notch2/genética , Factores de Transcripción SOXB1/genética
17.
Int J Hyperthermia ; 34(8): 1179-1185, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29458284

RESUMEN

PURPOSE: To determine the characteristics of ultrasound (US) imaging of completely ablated cases and the effects of duration and clinical experience on accurate microwave ablation (MWA) for the treatment of benign breast tumours. METHODS: With written informed consent and approval of the institutional ethics committee, patients with symptomatic or palpable benign breast tumours (longest diameter, 7-32 mm), to whom MWA (2450 MHz) was performed, were enrolled in this prospective nonrandomised study. US and contrast-enhanced US (CEUS) images were applied for follow-up and analysed. RESULTS: Forty-seven consecutive patients with 52 completely ablated tumours were enrolled. Of these 52 tumour ablations in US, 16 ablations were defined as concentric type, and 36 were defined as nonconcentric type. Of these 52 ablations, 7 cases were defined as nonaccurate ablation with the largest margin ≥10 mm in US. The nonaccurate ablation rate in the training group (the first consecutive 30 cases, 7/30) was significant higher than that (the last 22 cases, 0/22) in the practiced group (p = 0.016). Of 38 completely ablated cases (9 mm < the longest diameter <20 mm), the average largest margin in >70 s group was significant larger than that in <70 s group (p = 0.019). CONCLUSIONS: Experience was important for accurate MWA in the treatment of benign breast tumour, and at least 30 cases training was recommended. Nevertheless, clinical trials are still required to validate our findings in the future.


Asunto(s)
Técnicas de Ablación , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Microondas/uso terapéutico , Adolescente , Adulto , Humanos , Persona de Mediana Edad , Ultrasonografía , Adulto Joven
18.
J Transl Med ; 15(1): 23, 2017 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-28137271

RESUMEN

BACKGROUND: Minimally invasive therapies, such as microwave ablation (MWA), are widely used for the treatment of solid tumors. Previous studies suggest that MWA is feasible for the treatment of small breast cancer, and thermal ablation may induce adaptive antitumor immunity. However, the induced immune responses are mostly weak, and the immunomodulation effects of MWA in breast cancer are unclear. Immunostimulant OK-432 can induce tumor-specific T-cell responses and may augment the immunity induced by MWA. METHODS: We treated 4T1 breast cancer bearing BALB/c mice with MWA, OK-432, MWA plus OK-432, or left without treatment. Survival time was evaluated with the Kaplan-Meyer method comparing survival curves by log-rank test. On day 25 after ablation, surviving mice received tumor rechallenge, and the rechallenged tumor volumes were calculated every 5 days. Immunohistochemistry and flow cytometry were used to evaluate the T-cell immune responses in ablated tissues and spleens. The tumor-specific immunity was assessed by enzyme-linked immunospot assays. Besides, the cytokine patterns were identified from enzyme-linked immunosorbent assay. RESULTS: Microwave ablation plus OK-432 resulted in longer survival than single treatment and protect most surviving mice from tumor rechallenge. Both local and systemic T-cell responses were induced by MWA and were further enhanced by subsequent administration of OK-432. Moreover, the combination of MWA and OK-432 induced stronger tumor-specific immune responses than MWA alone. In addition, OK-432 and MWA synergistically promoted the production of Th1-type but not Th2-type cytokines, and polarized T-cell responses to Th1-dominant state. CONCLUSIONS: The T-cell immune responses were activated by MWA in breast cancer. Furthermore, the combination of MWA and OK-432 induced Th1-type response and elicited specific antitumor immunity.


Asunto(s)
Neoplasias Mamarias Animales/inmunología , Neoplasias Mamarias Animales/terapia , Microondas , Picibanil/uso terapéutico , Células TH1/inmunología , Animales , Línea Celular Tumoral , Polaridad Celular/efectos de los fármacos , Terapia Combinada , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Estimación de Kaplan-Meier , Neoplasias Mamarias Animales/patología , Ratones Endogámicos BALB C , Picibanil/administración & dosificación , Picibanil/farmacología , Análisis de Supervivencia , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología , Células TH1/efectos de los fármacos
19.
J Bone Miner Metab ; 35(5): 473-484, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27623790

RESUMEN

In order to explore the effects of calcitonin gene-related peptide (CGRP) on bone mesenchymal stem cells (BMSCs) from ovariectomized (OVX) rats, an OVX rat model was used. An ELISA was performed to examine the changes in CGRP level in the plasma and skeleton. The BMSCs from the sham rats were designated group A. The BMSCs from the OVX rats (groups B, C, D and E) were treated with different concentrations of CGRP (10-6, 10-8, 10-10 and 0 M) in vitro. The proliferation and osteogenic and adipogenic differentiation potential of the BMSCs were evaluated. BMSCs sheets and Bio-Oss® mixtures were transplanted into nude mice to observe the effects of CGRP on bone formation in vivo. The level of CGRP was decreased by almost 27 and 17 % in the plasma and bone, respectively, in OVX rats compared with sham rats (p < 0.05). Treatment with CGRP increased the proliferation and mineralization of BMSCs, and significantly decreased the lipid accumulation of BMSCs in a dose-dependent manner. The expression of Runx2 and Osterix was upregulated, but the expression of peroxisome proliferator-activated receptor γ was significantly downregulated in groups B, C and D compared with group E (p < 0.05). Micro computed tomography showed no difference between the images of the planted mixtures. Hematoxylin and eosin stain revealed the formation of slightly more hard bone-like structures in groups B and C. These results suggested that CGRP played a role in adjusting bone mass and strength by promoting the proliferation and osteogenic differentiation of BMSCs, as well as significantly suppressing the adipogenic differentiation of BMSCs.

20.
Nanotechnology ; 28(27): 275401, 2017 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-28531092

RESUMEN

We report the first demonstration of a high-efficiency photoelectrochemical (PEC) water splitting reaction using a novel Si NWs/WO3 core/shell photoanode prepared by a mild and inexpensive metal-catalyzed electroless etching process followed by dip-coating, airing and annealing methods. The dense and vertically aligned Si NWs/WO3 core/shell nanostructure were characterized by scanning electron microscopy, transmission electron microscopy and x-ray diffraction. In comparison to planar n-Si, Si NWs and planar Si/WO3, the Si NWs/WO3 samples showed significantly enhanced photocurrent over the entire potential sweep range. More significantly, the Si NWs/WO3 samples have an exceptionally low photocurrent onset potential of -0.6393 V versus reversible hydrogen electrode (RHE), indicating very efficient charge separation and charge transportation processes. The as-prepared electrode also has a photocurrent density of 2.7 mA cm-2 at 0.6107 V versus RHE in 0.5 M Na2SO4 solution under simulated solar light irradiation (100 mW cm-2 from 300 W Xenon lamp coupled with an AM 1.5 G filter). An optimal solar-to-hydrogen efficiency of about 1.9% was achieved at 0.2676 V versus RHE. Electrochemical impedance spectroscopy was conducted to investigate the properties of the charge transfer process, and the results indicated that the enhanced PEC performance may due to the increased charge separation. The x-ray photoelectron spectroscopy measurements indicated the chemical composition of the Si NWs/WO3 nanostructure. Our work has provided an efficient strategy to improve the energy conversion efficiency and photocurrent of water splitting materials.

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