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1.
Stem Cells Int ; 2021: 9886877, 2021.
Article in English | MEDLINE | ID: mdl-34712335

ABSTRACT

BACKGROUND: This study is aimed at investigating the safety and tolerability of the intra-arterial administration of autologous bone marrow-derived mesenchymal stem cells (BM-MSCs) in patients with multiple system atrophy- (MSA-) cerebellar type (MSA-C). METHODS: This was a single-center, open-label phase I clinical trial in patients with MSA-C. A three-stage dose escalation scheme (low-dose, 3.0 × 105 cells/kg; medium-dose, 6.0 × 105 cells/kg; high-dose, 9.0 × 105 cells/kg) was applied to determine the maximum tolerated dose of intra-arterial administration of BM-MSCs based on the no-observed-adverse-effect level derived from the toxicity study. The occurrence of adverse events was evaluated 1 day before and 1, 14, and 28 days after BM-MSC therapy. Additionally, we assessed changes in the Unified MSA Rating Scale (UMSARS) score 3 months after BM-MSC treatment. RESULTS: One serious adverse drug reaction (ADR) of leptomeningeal enhancement following the intra-arterial BM-MSC administration occurred in one patient in the low-dose group. The safety review of the Internal Monitoring Committee interpreted this as radiological evidence of the blood-brain barrier permeability for MSCs. No other ADRs were observed in the medium- or high-dose groups. In particular, no ischemic lesions on diffusion-weighted images were observed in any of the study participants. Additionally, the medium- and high-dose groups tended to show a slower increase in UMSARS scores than the low-dose group during the 3-month follow-up. CONCLUSION: The present study confirmed that a single intra-arterial administration of autologous BM-MSCs is a safe and promising neuroprotective strategy in patients with MSA-C.

2.
Artif Cells Nanomed Biotechnol ; 46(sup2): 87-95, 2018.
Article in English | MEDLINE | ID: mdl-29553850

ABSTRACT

Receptor tyrosine kinase Mer (MerTK) has been shown to be highly expressed in Glioblastoma multiforme (GBM) in comparison to its healthy counterpart and is implicated in brain tumorigenesis. Clarifying the underlying mechanism of MerTK induced invasiveness would result in novel strategies to improve patient's response to chemotherapeutics. In vitro and in vivo assays were performed to examine the functional role of cancer stem sell (CSC) maintenance in MerTK associated invasiveness. In this article, we demonstrate that apart from GBM cells, MerTK is also upregulated in GBM stem-like cells and associated with an increased infiltrative potential of brain tumors in vivo. Silencing of MerTK suppressed the self-renewal of patient-derived GBM stem-like cells. The signaling mechanisms by which MerTK contributes to CSC maintenance have largely been obscure. Molecular analyses revealed that high expression of the signal transducer and activator of transcription 3 (STAT3)- Kirsten rat sarcoma viral oncogene homolog (KRAS) and proto-oncogene tyrosine-protein kinase SRC axis supports MerTK-induced CSC maintenance in GBM spheroids. Furthermore, a short-hairpin RNA-mediated MerTK knockdown effectively blocked invasiveness and N-cadherin expression in mouse xenografts. Collectively, our results uncover a critical function of MerTK in CSC maintenance. Considering the low basal level of MerTK expression in healthy brain cells, evaluation of MerTK as a therapeutic target should advance the research into better therapeutics for GBM.


Subject(s)
Glioblastoma/pathology , Neoplastic Stem Cells/pathology , Proto-Oncogene Proteins p21(ras)/metabolism , STAT3 Transcription Factor/metabolism , Signal Transduction , c-Mer Tyrosine Kinase/metabolism , src-Family Kinases/metabolism , Animals , Cell Line, Tumor , Cell Transformation, Neoplastic , Gene Knockdown Techniques , Humans , Mice , Neoplasm Invasiveness , Prognosis , Proto-Oncogene Mas , c-Mer Tyrosine Kinase/deficiency , c-Mer Tyrosine Kinase/genetics
3.
Analyst ; 139(16): 3949-60, 2014 Aug 21.
Article in English | MEDLINE | ID: mdl-24918103

ABSTRACT

In this work, quantitative energy-dispersive electron probe X-ray microanalysis (ED-EPMA) (called low-Z particle EPMA), Raman microspectrometry (RMS), and attenuated total reflectance Fourier transform infrared spectroscopic (ATR-FTIR) imaging were applied in combination for the analysis of the same individual airborne particles for the first time. After examining individual particles of micrometer size by low-Z particle EPMA, consecutive examinations by RMS and ATR-FTIR imaging of the same individual particles were then performed. The relocation of the same particles on Al or Ag foils was successfully carried out among the three standalone instruments for several standard samples and an indoor airborne particle sample, resulting in the successful acquisition of quality spectral data from the three single-particle analytical techniques. The combined application of the three techniques to several different standard particles confirmed that those techniques provided consistent and complementary chemical composition information on the same individual particles. Further, it was clearly demonstrated that the three different types of spectral and imaging data from the same individual particles in an indoor aerosol sample provided richer information on physicochemical characteristics of the particle ensemble than that obtainable by the combined use of two single-particle analytical techniques.

4.
Anal Chem ; 86(5): 2648-56, 2014 Mar 04.
Article in English | MEDLINE | ID: mdl-24506470

ABSTRACT

The influence of six collecting substrates with different physical properties on the hygroscopicity measurement of inorganic aerosol particle surrogates and the potential applications of these substrates were examined experimentally. Laboratory-generated single salt particles, such as NaCl, KCl, and (NH4)2SO4, 1-5 µm in size, were deposited on transmission electron microscopy grids (TEM grids), parafilm-M, Al foil, Ag foil, silicon wafer, and cover glass. The particle hygroscopic properties were examined by optical microscopy. Contact angle measurements showed that parafilm-M is hydrophobic, and cover glass, silicon wafer, Al foil, and Ag foil substrates are hydrophilic. The observed deliquescence relative humidity (DRH) values for NaCl, KCl, and (NH4)2SO4 on the TEM grids and parafilm-M substrates agreed well with the literature values, whereas the DRHs obtained on the hydrophilic substrates were consistently ∼1-2% lower, compared to those on the hydrophobic substrates. The water layer adsorbed on the salt crystals prior to deliquescence increases the Gibb's free energy of the salt crystal-substrate system compared to the free energy of the salt droplet-substrate system, which in turn reduces the DRHs. The hydrophilic nature of the substrate does not affect the measured efflorescence RH (ERH) values. However, the Cl(-) or SO4(2-) ions in aqueous salt droplets seem to have reacted with Ag foil to form AgCl or Ag2SO4, respectively, which in turn acts as seeds for the heterogeneous nucleation of the original salts, leading to higher ERHs. The TEM grids were found to be most suitable for the hygroscopic measurements of individual inorganic aerosol particles by optical microscopy and when multiple analytical techniques, such as scanning electron microscopy-energy dispersive X-ray spectroscopy, TEM-EDX, and/or Raman microspectrometry, are applied to the same individual particles.

5.
Anal Chem ; 85(21): 10424-31, 2013 Nov 05.
Article in English | MEDLINE | ID: mdl-24069900

ABSTRACT

Quantitative energy-dispersive electron probe X-ray microanalysis (ED-EPMA), known as low-Z particle EPMA, and Raman microspectrometry (RMS) were applied in combination for an analysis of the iron species in airborne PM10 particles collected in underground subway tunnels. Iron species have been reported to be a major chemical species in underground subway particles generated mainly from mechanical wear and friction processes. In particular, iron-containing particles in subway tunnels are expected to be generated with minimal outdoor influence on the particle composition. Because iron-containing particles have different toxicity and magnetic properties depending on their oxidation states, it is important to determine the iron species of underground subway particles in the context of both indoor public health and control measures. A recently developed analytical methodology, i.e., the combined use of low-Z particle EPMA and RMS, was used to identify the chemical species of the same individual subway particles on a single particle basis, and the bulk iron compositions of airborne subway particles were also analyzed by X-ray diffraction. The majority of airborne subway particles collected in the underground tunnels were found to be magnetite, hematite, and iron metal. All the particles collected in the tunnels of underground subway stations were attracted to permanent magnets due mainly to the almost ubiquitous ferrimagnetic magnetite, indicating that airborne subway particles can be removed using magnets as a control measure.


Subject(s)
Air Pollutants/chemistry , Iron/chemistry , Spectrometry, X-Ray Emission/methods , Spectrum Analysis, Raman/methods , X-Ray Diffraction
6.
Food Chem ; 139(1-4): 231-40, 2013 Aug 15.
Article in English | MEDLINE | ID: mdl-23561100

ABSTRACT

Alcoholic liver disease (ALD) can be developed by a prolonged or large intake of alcohol in a short period of time. ALD is considered as a leading cause for a liver injury in modern dietary life. This study was aimed to investigate the effects of orally administrated citrus flavonoids (CFs) and their enzymatically modified ones (EM-CFs) to prevent ALD. Hesperidin and narirutin were extracted from peels of Citrus unshiu by ultra-sonication and purified further. These CFs were modified enzymatically through glycosylation and de-rhamnosylation by the actions of cyclodextrin glucanotransferase (CGTase) and hesperidinase, respectively. CFs and EM-CFs were fed to ICR mouse along with ethanol for 8 weeks, and changes in lipid contents, lipid peroxidation, GSH, antioxidant enzymes activity and proinflammatory cytokines in hepatic tissues were observed. Administration of CFs and EM-CFs along with alcohol significantly suppressed increases in prognostic parameters of a hepatocellular injury. Especially, EM-CFs fed groups maintained malondialdehyde, GSH levels and catalase activity in hepatic tissues close to those of the normal diet fed group. Abrupt increases in proinflammatory cytokines such as IκB-α, TNF-α, IL-1ß and IL-6 in hepatocytes due to a chronic alcohol uptake were significantly suppressed by co-administration of EM-CFs. These results indicate that although the administration of CFs can alleviate ALD through preventing excessive lipid formation, protecting the antioxidant system and suppressing induction of inflammation in hepatocytes, their effectiveness can be further improved by glycosylation and de-rhamnosylation.


Subject(s)
Citrus/chemistry , Flavonoids/administration & dosage , Liver Diseases, Alcoholic/drug therapy , Protective Agents/administration & dosage , Animals , Bacterial Proteins/chemistry , Flavonoids/chemistry , Fungal Proteins/chemistry , Glucosyltransferases/chemistry , Glutathione/metabolism , Glycoside Hydrolases/chemistry , Hepatocytes/drug effects , Hepatocytes/enzymology , Hepatocytes/metabolism , Humans , Lipid Peroxidation/drug effects , Liver Diseases, Alcoholic/metabolism , Liver Diseases, Alcoholic/prevention & control , Male , Malondialdehyde/metabolism , Mice , Mice, Inbred ICR , Molecular Structure , Penicillium/enzymology , Protective Agents/chemistry , Rats , Rats, Sprague-Dawley , Superoxide Dismutase/metabolism , Thermoanaerobacter/enzymology
7.
Food Chem Toxicol ; 55: 637-44, 2013 May.
Article in English | MEDLINE | ID: mdl-23416143

ABSTRACT

This study aimed to demonstrate protective activities of the narirutin fraction from peels of Citrus unshiu against ethanol-induced hepatic damage through an animal study. Citrus narirutin fraction (CNF), contained 75% of narirutin, was obtained by an ultra-sonicated extraction and further purification. ICR mice were divided into four groups; normaldiet control, ethanol control (6.5g ethanol/kg), low-CNF (ethanol+150mg CNF/kg) and high-CNF (ethanol+300mg CNF/kg) groups. Consumption of alcohol for 8weeks induced severe liver damage with increases in prognostic indicators such as aspartate transaminase, alanine transaminase in serum whereas co-administration of CNF suppressed their increases. Excessive accumulations in liver TG and TC in ethanol control group were also suppressed by co-administration of CNF. Co-administration of CNF maintained SOD activity, GSH and malondialdehyde levels close to those of the normal diet group. Chronic consumption of alcohol also stimulated abrupt increases in pro-inflammatory cytokines such as nuclear factor (NF)-κB, tumor necrosis factor (TNF)-α and interleukin (IL)-1ß in liver otherwise co-administration of CNF effectively suppressed production of these cytokines dose-dependently. These results indicate that co-administration of CNF with alcohol can alleviate alcohol induced liver damage through preventing lipid formation, protecting antioxidant system and suppressing productions of pro-inflammatory cytokines.


Subject(s)
Citrus/chemistry , Disaccharides/therapeutic use , Flavanones/therapeutic use , Liver Diseases, Alcoholic/drug therapy , Animals , Body Weight/drug effects , Disaccharides/isolation & purification , Disaccharides/pharmacology , Flavanones/isolation & purification , Flavanones/pharmacology , Glutathione/metabolism , Interleukin-1beta/biosynthesis , Liver/drug effects , Liver Diseases, Alcoholic/enzymology , Liver Diseases, Alcoholic/metabolism , Male , Malondialdehyde/metabolism , Mice , Mice, Inbred ICR , NF-kappa B/biosynthesis , Organ Size/drug effects , Superoxide Dismutase/metabolism , Tumor Necrosis Factor-alpha/biosynthesis
8.
Food Chem Toxicol ; 50(10): 3498-504, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22813871

ABSTRACT

In this study, we examined the regulatory activity of narirutin fraction from citrus peels on the production of inflammatory mediators managing acute or chronic inflammatory diseases in macrophages. Narirutin fraction inhibited the release, by lipopolysaccharide (LPS)-stimulated macrophages, of nitric oxide (NO) and prostaglandin E2 (PGE2) through suppressing the expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), respectively. The release, by LPS stimulated macrophages, of interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) was also reduced by narirutin fraction in a dose-dependent manner. Furthermore, narirutin fraction inhibited the LPS-mediated activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs), which are signaling molecules involved in production of pro-inflammatory factors. As a result of these properties, narirutin fraction has the potential to be used as a functional dietary supplement and effective anti-inflammatory agent.


Subject(s)
Citrus/chemistry , Disaccharides/pharmacology , Flavanones/pharmacology , Lipopolysaccharides/toxicity , Mitogen-Activated Protein Kinase Kinases/metabolism , NF-kappa B/antagonists & inhibitors , Animals , Cell Line , Cell Survival/drug effects , Cyclooxygenase 2/genetics , Cyclooxygenase 2/metabolism , Cytokines/genetics , Cytokines/metabolism , Dinoprostone/genetics , Dinoprostone/metabolism , Disaccharides/chemistry , Flavanones/chemistry , Fruit/chemistry , Gene Expression Regulation, Enzymologic/drug effects , Macrophages/drug effects , Macrophages/metabolism , Mice , Mitogen-Activated Protein Kinase Kinases/genetics , Molecular Structure , NF-kappa B/genetics , NF-kappa B/metabolism , Nitric Oxide/metabolism , Plant Extracts/chemistry
9.
Anal Chem ; 84(7): 3145-54, 2012 Apr 03.
Article in English | MEDLINE | ID: mdl-22380789

ABSTRACT

In this work, quantitative electron probe X-ray microanalysis (EPMA) and Raman microspectrometry (RMS) were applied in combination for the first time to characterize the complex internal structure and physicochemical properties of the same ensemble of Asian dust particles. The analytical methodology to obtain the chemical composition, mixing state, and spatial distribution of chemical species within single particles through the combined use of the two techniques is described. Asian dust aerosol particles collected in Incheon, Korea, during a moderate dust storm event were examined to assess the applicability of the methodology to resolve internal mixtures within single particles. Among 92 individual analyzed particles, EPMA and RMS identified 53% of the particles to be internally mixed with two or more chemical species. Information on the spatial distribution of chemical compounds within internally mixed individual particles can be useful for deciphering the particle aging mechanisms and sources. This study demonstrates that the characterization of individual particles, including chemical speciation and mixing state analysis, can be performed more in detail using EPMA and RMS in combination than with the two single-particle techniques alone.

10.
Anal Chem ; 82(19): 7999-8009, 2010 Oct 01.
Article in English | MEDLINE | ID: mdl-20698495

ABSTRACT

In this work, an analytical method for the characterization of the hygroscopic property, chemical composition, and morphology of individual aerosol particles is introduced. The method, which is based on the combined use of optical and electron microscopic techniques, is simple and easy to apply. An optical microscopic technique was used to perform the visual observation of the phase transformation and hygroscopic growth of aerosol particles on a single particle level. A quantitative energy-dispersive electron probe X-ray microanalysis, named low-Z particle EPMA, was used to perform a quantitative chemical speciation of the same individual particles after the measurement of the hygroscopic property. To validate the analytical methodology, the hygroscopic properties of artificially generated NaCl, KCl, (NH(4))(2)SO(4), and Na(2)SO(4) aerosol particles of micrometer size were investigated. The practical applicability of the analytical method for studying the hygroscopic property, chemical composition, and morphology of ambient aerosol particles is demonstrated.

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