837 research outputs found
Licochalcone A exerts antitumor activity in bladder cancer cell lines and mice models
Purpose: To investigate the effect of licochalcone A (LA) on the inhibition of cell proliferation and ERK1/2 phosphorylation in bladder carcinoma cell lines.Methods: Cell viability was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay. Dye-binding method was used to examine the concentration of proteins. Lymphocytes were extracted from mice and after surface staining were subjected to BD fixation and permeabilization for intracellular staining. Flow cytometry was used to measure cellular fluorescence.Results: MTT results revealed a significant decrease in the proliferation of UM-UC-3, J82 and HT-1197 cell lines on treatment with LA. LA also induced reduction in phosphorylation of ERK1/2 in all three carcinoma cell lines. In the mouse model, licochalcone A treatment via intraperitoneal (ip) administration induced a significant decrease in the level of regulatory T cells (Tregs). Comparison of the mouse interferon-α (IFN-α)-treated and LA-treated groups revealed that LA treatment caused enhancement of cytotoxic T lymphocyte (CTL) activity similar to that of IFN-α. Administration of UM-UC-3 cells in C3H/HeN mice resulted in marked reduction in the counts for splenocytes and CD4+ CD25+ Foxp3+ T (regulatory T cells) cell proportion in LA-treated mice compared to untreated control group.Conclusion: Licochalcone A may be of therapeutic importance for the prevention of bladder carcinoma. However, studies are required to ascertain the compound’s usefulness in this regard.Keywords: Licochalcone A, Bladder carcinoma, Splenocytes, Phosphorylation, Cell proliferation, Interfero
Research progress of polyphenols in edible plant enzymes
Polyphenol is one of the characteristic physical and chemical indexes of edible plant enzyme, which has the effects of anti-oxidation, reducing fat and anti-tumor. This paper reviews the composition of polyphenols in food plant enzyme products, the factors affecting the formation of polyphenols in food plant enzyme products, the health care effects of polyphenols, and the further research directions of polyphenols in edible plant enzymes are also prospected
Effect of total flavones of buckwheat flowers and leaves on protein tyrosine phosphatase 1B expression in type 2 diabetic rats
The total flavone content was obtained from flowers and leaf of buckwheat (Fagopyrum esculentum Moench) by heating reflux method. The effects of the total flavone extract on the protein tyrosine phosphatase 1B (PTP1B) expression in type 2 diabetic rats were evaluated by immunofluorescence, western blotting and real-time quantitative PCR. The results suggested that the total flavone fraction from buckwheat flowers and leaves can significantly decrease the PTP1B expression in liver.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Quantitative Analysis of Sodium Metal Deposition and Interphase in Na Metal Batteries
Sodium-ion batteries exhibit significant promise as a viable alternative to
current lithium-ion technologies owing to their sustainability, low cost per
energy density, reliability, and safety. Despite recent advancements in cathode
materials for this category of energy storage systems, the primary challenge in
realizing practical applications of sodium-ion systems is the absence of an
anode system with high energy density and durability. Although Na metal is the
ultimate anode that can facilitate high-energy sodium-ion batteries, its use
remains limited due to safety concerns and the high-capacity loss associated
with the high reactivity of Na metal. In this study, titration gas
chromatography is employed to accurately quantify the sodium inventory loss in
ether- and carbonate-based electrolytes. Uniaxial pressure is developed as a
powerful tool to control the deposition of sodium metal with dense morphology,
thereby enabling high initial coulombic efficiencies. In ether-based
electrolytes, the Na metal surface exhibits the presence of a uniform solid
electrolyte interphase layer, primarily characterized by favorable inorganic
chemical components with close-packed structures. The full cell, utilizing a
controlled electroplated sodium metal in ether-based electrolyte, provides
capacity retention of 91.84% after 500 cycles at 2C current rate and delivers
86 mAh/g discharge capacity at 45C current rate, suggesting the potential to
enable Na metal in the next generation of sodium-ion technologies with
specifications close to practical requirements
Screening therapeutic EMT blocking agents in a three-dimensional microenvironment
Epithelial–mesenchymal transition (EMT) plays a critical role in the early stages of dissemination of carcinoma leading to metastatic tumors, which are responsible for over 90% of all cancer-related deaths. Current therapeutic regimens, however, have been ineffective in the cure of metastatic cancer, thus an urgent need exists to revisit existing protocols and to improve the efficacy of newly developed therapeutics. Strategies based on preventing EMT could potentially contribute to improving the outcome of advanced stage cancers. To achieve this goal new assays are needed to identify targeted drugs capable of interfering with EMT or to revert the mesenchymal-like phenotype of carcinoma to an epithelial-like state. Current assays are limited to examining the dispersion of carcinoma cells in isolation in conventional 2-dimensional (2D) microwell systems, an approach that fails to account for the 3-dimensional (3D) environment of the tumor or the essential interactions that occur with other nearby cell types in the tumor microenvironment. Here we present a microfluidic system that integrates tumor cell spheroids in a 3D hydrogel scaffold, in close co-culture with an endothelial monolayer. Drug candidates inhibiting receptor activation or signal transduction pathways implicated in EMT have been tested using dispersion of A549 lung adenocarcinoma cell spheroids as a metric of effectiveness. We demonstrate significant differences in response to drugs between 2D and 3D, and between monoculture and co-culture.Singapore. National Research Foundation (Singapore MIT Alliance for Research and Technology's BioSystems and Micromechanics Inter-Disciplinary Research programme)National University of Singapore (Cancer Science Institute)Singapore. Agency for Science, Technology and ResearchSingapore. Institute of Molecular and Cell Biology (IMCB core funding A*STAR
Clonal dissemination of invasive and colonizing clonal complex 1 of serotype VI group B Streptococcus in central Taiwan
Background/PurposeThe aim of this study was to investigate clinical presentation, serotype distribution and genetic correlation of group B streptococcus (GBS) diseases. Since serotype VI prevalence far exceeded that reported in prior studies, genetic relationship of isolates was further analyzed.MethodsGBS isolates obtaining from patients with invasive diseases and pregnant women with colonization between June 2007 and December 2010 were analyzed. All isolates were tested for serotypes by multiplex PCR assay and pulsed-field gel electrophoresis (PFGE). Serotype VI isolates were further analyzed by multilocus sequence typing (MLST).ResultsA total of 134 GBS isolates were recovered from blood of 126 patients with invasive disease (94.0%) and anogenital swabs of 8 pregnant women (6.0%). Most common serotype was Ib (21.6%), followed by V (20.1%), VI (18.7%), III (15.7%), II (11.9 %), Ia (11.2%), and IX (0.7%). Serotype VI was also the leading type in infants with early onset disease (EOD; 3/8, 37.5%) and colonizing pregnant women (3/8, 37.5%). PFGE distinguished 33 pulsotypes, reflecting genetic diversity among GBS isolates. Among 25 serotype VI isolates tested, 14 were ST-1, seven were ST-679, three were ST-678, one was ST-681, and distributed into four PFGE pulsotypes. ST-678, ST-679, and ST-681 were novel sequence types; ST-678 and ST-679 are single-locus variants of ST-1 that belongs to clonal complex (CC) 1.ConclusionCC1 dissemination of serotype VI GBS thus emerges as an important invasive pathogen in infants and nonpregnant adults in central Taiwan. Serotype prevalence of GBS must be continuously monitored geographically to guide prevention strategy of GBS vaccines
Screening therapeutic EMT blocking agents in a three-dimensional microenvironment
Epithelial–mesenchymal transition (EMT) plays a critical role in the early stages of dissemination of carcinoma leading to metastatic tumors, which are responsible for over 90% of all cancer-related deaths. Current therapeutic regimens, however, have been ineffective in the cure of metastatic cancer, thus an urgent need exists to revisit existing protocols and to improve the efficacy of newly developed therapeutics. Strategies based on preventing EMT could potentially contribute to improving the outcome of advanced stage cancers. To achieve this goal new assays are needed to identify targeted drugs capable of interfering with EMT or to revert the mesenchymal-like phenotype of carcinoma to an epithelial-like state. Current assays are limited to examining the dispersion of carcinoma cells in isolation in conventional 2-dimensional (2D) microwell systems, an approach that fails to account for the 3-dimensional (3D) environment of the tumor or the essential interactions that occur with other nearby cell types in the tumor microenvironment. Here we present a microfluidic system that integrates tumor cell spheroids in a 3D hydrogel scaffold, in close co-culture with an endothelial monolayer. Drug candidates inhibiting receptor activation or signal transduction pathways implicated in EMT have been tested using dispersion of A549 lung adenocarcinoma cell spheroids as a metric of effectiveness. We demonstrate significant differences in response to drugs between 2D and 3D, and between monoculture and co-culture.Singapore. National Research Foundation (Singapore MIT Alliance for Research and Technology's BioSystems and Micromechanics Inter-Disciplinary Research programme)National University of Singapore (Cancer Science Institute)Singapore. Agency for Science, Technology and ResearchSingapore. Institute of Molecular and Cell Biology (IMCB core funding A*STAR
First Ground Observations of OI5577 Green Line Emission over the Taiwan Area
Worldwide ground observations of upper atmospheric airglow with particular emphasis on the OI 557.7 and 630 nm emissions have been conducted since 1960s. This study reports the first ground observations of OI 557.7 nm green line emission over the Taiwan area. For comparison, the background continuum at 530 nm was also measured by the same system. The experiments were conducted during the period of Aug - Dec, 2004 at various locations in Taiwan using a self-developed photometer instrument. Daily height integrated intensity of the night-time green line emission may vary in the range of 80 - 210 Rayleighs and twilight enhancement is also identified. The observational results may serve as a useful reference for follow-up sounding rocket measurements of OI 557.7 nm airglow emission over the Taiwan area
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