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1.
Nanomaterials (Basel) ; 13(1)2022 Dec 23.
Article in English | MEDLINE | ID: mdl-36615973

ABSTRACT

Surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) is performed using carbon nanowalls (CNWs) for ionization-assisting substrates. The CNWs (referred to as high-quality CNWs) in the present study were grown using a radical-injection plasma-enhanced chemical vapor deposition (RI-PECVD) system with the addition of oxygen in a mixture of CH4 and H2 gases. High-quality CNWs were different with respect to crystallinity and C-OH groups, while showing similar wall-to-wall distances and a wettability comparable to CNWs (referred to as normal CNWs) grown without O2. The efficiency of SALDI was tested with both parameters of ion intensity and fragmental efficiency (survival yield (SY)) using N-benzylpyridinuim chloride (N-BP-CI). At a laser fluence of 4 mJ/cm2, normal CNWs had an SY of 0.97 and an ion intensity of 0.13, while 5-sccm-O2- high-quality CNWs had an SY of 0.89 and an ion intensity of 2.55. As a result, the sensitivity for the detection of low-molecular-weight analytes was improved with the high-quality CNWs compared to the normal CNWs, while an SY of 0.89 was maintained at a low laser fluence of 4 mJ/cm2. SALDI-MS measurements available with the high-quality CNWs ionization-assisting substrate provided high ionization and SY values.

2.
Nanomaterials (Basel) ; 11(2)2021 Jan 20.
Article in English | MEDLINE | ID: mdl-33498479

ABSTRACT

Carbon nanowalls (CNWs), which are vertically oriented multi-layer graphene sheets, were employed in surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) measurements to detect low-molecular-weight organic compounds. CNWs substrates with widely different wall-to-wall distances from 142 to 467 nm were synthesized using a radical-injection plasma-enhanced chemical vapor deposition (RI-PECVD) system with nanosecond pulse biasing to a sample stage. When survival yield (SY) values of N-benzylpyridinium chloride (N-BP-Cl) were examined, which is commonly used to evaluate desorption/ionization efficiency, a narrower wall-to-wall distance presented a higher SY value. The highest SY value of 0.97 was realized at 4 mJ/cm2 for the highest-density CNWs with a wall-to-wall distance of 142 nm. The laser desorption/ionization effect of arginine, an amino acid, was also investigated. When CNWs with a narrower wall-to-wall distance were used, the signal-to-noise (SN) ratios of the arginine signals were increased, while the intensity ratios of fragment ions to arginine signals were suppressed. Therefore, the CNWs nanostructures are a powerful tool when used as a SALDI substrate for the highly efficient desorption/ionization of low-molecular-weight biomolecules.

3.
Bioorg Med Chem Lett ; 30(13): 127222, 2020 07 01.
Article in English | MEDLINE | ID: mdl-32386978

ABSTRACT

Pro-fluorescent labeled oligonucleotides are potential alternative tools to classical fluorescently labeled oligonucleotides for monitoring cellular uptake. Here, we report the design and synthesis of a thiol-responsive pro-fluorophore labeled oligonucleotide, and its fluorescence responsivity to glutathione in the test tube and live cells.


Subject(s)
Fluorescent Dyes/pharmacokinetics , Glutathione/metabolism , Oligonucleotides/pharmacokinetics , Rhodamines/pharmacokinetics , Biological Transport , Fluorescence , Fluorescent Dyes/chemical synthesis , Fluorescent Dyes/metabolism , HeLa Cells , Humans , Oligonucleotides/chemical synthesis , Oligonucleotides/metabolism , Rhodamines/chemical synthesis , Rhodamines/metabolism
4.
Org Lett ; 21(4): 862-866, 2019 02 15.
Article in English | MEDLINE | ID: mdl-30714380

ABSTRACT

Glutathione-labile protecting groups for phosphodiester moieties in oligonucleotides were designed, synthesized, and incorporated into oligonucleotides. The protecting groups on the phosphodiester moieties were cleaved in a buffer containing 10 mM glutathione, which was used as a model of intracellular fluid. Cellular uptake of oligonucleotides bearing glutathione-labile protecting groups was strongly affected by the location and number of the protecting groups.


Subject(s)
Drug Design , Glutathione/chemistry , Oligonucleotides/pharmacokinetics , HeLa Cells , Humans , Molecular Structure , Oligonucleotides/chemical synthesis , Oligonucleotides/chemistry
5.
Gan To Kagaku Ryoho ; 45(12): 1733-1736, 2018 Dec.
Article in Japanese | MEDLINE | ID: mdl-30587730

ABSTRACT

It has been reported that docetaxel, cisplatin, and 5-FU combination chemotherapy(DCF)is effective for advanced esophageal cancer. However, we often encounter severe hematotoxicity during DCF therapy. Here, we retrospectively analyzed the data of patients with advanced esophageal cancer treated with DCF at our department, and assessed the efficacy of pegfilgrastim and the issues associated with its use. According to the results, pegfilgrastim may reduce the severe hematotoxicity associated with DCF therapy and may contribute to the maintenance of the intensity of DCF. However, neutropenia had already occurred before pegfilgrastim administration on day 7 in most patients. Therefore, the appropriate timing of pegfilgrastim administration in DCF must be determined in a future prospective study.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Esophageal Neoplasms , Filgrastim , Neutropenia , Polyethylene Glycols , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cisplatin/administration & dosage , Docetaxel/administration & dosage , Esophageal Neoplasms/drug therapy , Filgrastim/therapeutic use , Fluorouracil/administration & dosage , Humans , Neutropenia/chemically induced , Neutropenia/prevention & control , Polyethylene Glycols/therapeutic use , Prospective Studies , Retrospective Studies , Taxoids
6.
Biointerphases ; 12(3): 031006, 2017 Aug 02.
Article in English | MEDLINE | ID: mdl-28768419

ABSTRACT

The multiplex coherent anti-Stokes Raman scattering microscopy allowed label-free visualization of cytoplasmic lipid droplets (LDs). The LDs, which act to conserve energy storage, are usually accumulated during the normal apoptosis of HeLa cells with activation of caspase-3/7 leading to downregulation of the fatty acid catabolism pathways. During cultivating in nonthermal plasma-activated medium (PAM), while the activation of caspase-3/7 was induced, the authors found that a dynamic exhaustion of the intracellular LDs, underlying the metabolic mechanism of the PAM-induced apoptotic cell death of HeLa cells.


Subject(s)
Apoptosis/drug effects , Caspase 3/metabolism , Caspase 7/metabolism , Lipid Droplets/metabolism , Nonlinear Optical Microscopy , Plasma Gases/pharmacology , Enzyme Activation/drug effects , HeLa Cells , Humans
7.
Phys Chem Chem Phys ; 19(21): 13438-13442, 2017 May 31.
Article in English | MEDLINE | ID: mdl-28503685

ABSTRACT

Interactions between non-equilibrium atmospheric-pressure plasma (NEAPP) and living cells were examined using multiplex coherent anti-Stokes Raman scattering (CARS) microscopy. Our multiplex CARS analyses revealed that NEAPP irradiation generates short-lived radicals that induce a decrease in the mitochondrial activity of budding yeast cells.


Subject(s)
Plasma Gases/adverse effects , Saccharomyces cerevisiae/radiation effects , Cell Survival/drug effects , Cell Survival/radiation effects , Mitochondria/drug effects , Mitochondria/radiation effects , Nonlinear Optical Microscopy , Plasma Gases/chemistry , Reactive Nitrogen Species/adverse effects , Reactive Oxygen Species/adverse effects , Saccharomyces cerevisiae/chemistry , Ultraviolet Rays
8.
Appl Opt ; 54(23): 7088-93, 2015 Aug 10.
Article in English | MEDLINE | ID: mdl-26368380

ABSTRACT

We investigate silicon wafer temperature measurement characteristics based on optical low-coherence interferometry by altering the light source wavelength. Variations in Si wafer optical thickness with temperature are expressed by thermal expansion and the refractive index. The optical characteristics determine the measurement precision and range. In this study, the measurement precision and the measurable temperature range were evaluated for three wavelengths: 1040, 1310, and 1550 nm. The maximum measurable temperature at 1040 nm was the lowest because of signal light absorption caused by fundamental interband absorption. The measurement precision at 1040 nm was the highest at 0.020°C because optical thickness changes per degree C increase with decreasing wavelength.

9.
ACS Appl Mater Interfaces ; 6(16): 13461-9, 2014 Aug 27.
Article in English | MEDLINE | ID: mdl-25078882

ABSTRACT

Cl-doped ZnO-nanowire (Cl:ZnO-nws)/Cu2O photovoltaic devices were prepared by electrodeposition in aqueous solutions, and the effects of the insertion of the highly resistive ZnO (i-ZnO) layer has been demonstrated by an improvement of the photovoltaic performance. The Cl:ZnO-nws and i-ZnO layer were prepared by electrodeposition in a zinc chloride aqueous solution with saturated molecular oxygen and simple zinc nitrate aqueous solution, respectively. The i-ZnO layer was directly deposited on the Cl:ZnO-nws and suppressed the electrodeposition of the Cu2O layer on the Cl:ZnO-nws. The insertion of the i-ZnO layer between the Cl:ZnO-nws and Cu2O layers induced an improvement in the photovoltaic performance from 0.40 to 1.26% with a 0.35 V open circuit voltage, 7.1 mA·cm(-2) short circuit current density, and 0.52 fill factor due to the reduction of the recombination loss.

10.
Appl Phys Lett ; 96(15): 153704, 2010 Apr 12.
Article in English | MEDLINE | ID: mdl-20461224

ABSTRACT

A promising, environmentally safe method for inactivating fungal spores of Penicillium digitatum, a difficult-to-inactivate food spoilage microorganism, was developed using a high-density nonequilibrium atmospheric pressure plasma (NEAPP). The NEAPP employing Ar gas had a high electron density on the order of 10(15) cm(-3). The spores were successfully and rapidly inactivated using the NEAPP, with a decimal reduction time in spores (D value) of 1.7 min. The contributions of ozone and UV radiation on the inactivation of the spores were evaluated and concluded to be not dominant, which was fundamentally different from the conventional sterilizations.

11.
Diabetes Care ; 33(1): 150-5, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20040674

ABSTRACT

OBJECTIVE: Our goal was to ascertain the prevalence of pruritus in diabetic and nondiabetic subjects and the relevance of symptoms, signs, and nerve functions of diabetic polyneuropathy (DPN) of pruritus. RESEARCH DESIGN AND METHODS: A large-scale survey of 2,656 diabetic outpatients and 499 nondiabetic subjects was performed. In diabetic subjects, the relationship between pruritus and age, sex, diabetic duration, A1C, Achilles tendon reflex (ATR), and abnormal sensation in legs was evaluated. In 105 diabetic subjects, nerve conduction studies, quantitative vibratory threshold (QVT), heart rate variability, and a fall of systolic blood pressure at a head-up tilt test (DeltaBP) were performed, and the relationships between pruritus and nerve functions were evaluated. RESULTS: Although the prevalence of truncal pruritus of unknown origin (TPUO) in diabetic subjects was significantly higher than that in age-matched nondiabetic subjects (11.3 vs. 2.9%, P = 0.0001), the prevalence of other pruritus was not different between the two groups. Multiple logistic regression analysis revealed that abnormal sensation and ATR areflexia were independent risk factors for TPUO in age, sex, duration of diabetes, and A1C. DeltaBP in diabetic subjects with TPUO was significantly impaired compared with that in those without TPUO. Larger DeltaBP was identified as a significant risk factor of TPUO independent of other nerve dysfunctions by multiple logistic regression analysis. CONCLUSIONS: TPUO is significantly more frequent in diabetic than in nondiabetic individuals. TPUO is significantly associated with symptoms and signs of DPN, including impaired blood pressure response in a head-up tilt test. TPUO, therefore, might be a newly recognized symptom of DPN.


Subject(s)
Diabetic Neuropathies/diagnosis , Diabetic Neuropathies/physiopathology , Pruritus/etiology , Pruritus/pathology , Adult , Age Distribution , Aged , Aged, 80 and over , Diabetic Neuropathies/epidemiology , Female , Humans , Male , Middle Aged , Pruritus/epidemiology , Young Adult
12.
Appl Spectrosc ; 63(5): 555-8, 2009 May.
Article in English | MEDLINE | ID: mdl-19470213

ABSTRACT

We demonstrate the monitoring of plant nutrients in leaves of Citrus unshiu and Rhododendron obtusum using low-energy (<1 mJ) laser-induced breakdown spectroscopy. The raw plant leaf was successfully ablated without desiccation before laser irradiation, by applying metallic colloidal particles to the leaf surface. The emission intensity with the metallic particles was larger than that without the particles. This result indicates an improvement of the sensitivity and the detection limit of laser-induced breakdown spectroscopy. The emission enhancement was caused by localized surface plasmon resonance and was dependent on the size and material of metallic particles.


Subject(s)
Citrus/chemistry , Plant Leaves/chemistry , Rhododendron/chemistry , Spectrum Analysis/methods , Surface Plasmon Resonance/methods , Colloids/chemistry , Gold/chemistry , Lasers , Sensitivity and Specificity , Silver/chemistry , Surface Properties
13.
Biochem Biophys Res Commun ; 377(1): 205-9, 2008 Dec 05.
Article in English | MEDLINE | ID: mdl-18840400

ABSTRACT

The aorta-gonad-mesonephros (AGM) region is involved in the generation and maintenance of the first definitive hematopoietic stem cells (HSCs). A mouse AGM-derived cell line, AGM-S3, was shown to support the development of HSCs. To elucidate the molecular mechanisms regulating early hematopoiesis, we obtained subclones from AGM-S3, one of which was hematopoiesis supportive (S3-A9) and the other one of which was non-supportive (S3-A7), and we analyzed their gene expression profiles by gene chip analysis. In the present study, we found that Glypican-1 (GPC1) was highly expressed in the supportive subclone AGM-S3-A9. Over-expression of GPC1 in non-supportive cells led to the proliferation of progenitor cells in human cord blood when cocultured with the transfected-stromal cells. Thus, GPC1 may have an important role in the establishment of a microenvironment that supports early events in hematopoiesis.


Subject(s)
Aorta/metabolism , Gene Expression Regulation, Developmental , Glypicans/genetics , Gonads/metabolism , Hematopoiesis/genetics , Mesonephros/metabolism , Animals , Aorta/cytology , Aorta/embryology , Cell Line , Cell Proliferation , Fetal Blood/cytology , Fetal Blood/metabolism , Gene Expression Profiling , Glypicans/physiology , Gonads/cytology , Gonads/embryology , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/metabolism , Humans , Mesonephros/cytology , Mice , Stromal Cells/cytology , Stromal Cells/metabolism , Transfection
14.
Proc Natl Acad Sci U S A ; 103(7): 2202-7, 2006 Feb 14.
Article in English | MEDLINE | ID: mdl-16461905

ABSTRACT

The interaction between stem cells and their supportive microenvironment is critical for their maintenance, function, and survival. Whereas hematopoietic stem cells (HSCs) are among the best characterized of tissue stem cells, their precise site of residence (referred to as the niche) in the adult bone marrow has not been precisely defined. In this study, we found that a Gata2 promoter directs activity in all HSCs. We show that HSCs can be isolated efficiently from bone marrow cells by following Gata2-directed GFP fluorescence, and that they can also be monitored in vivo. Each individual GFP-positive cell lay in a G0/G1 cell cycle state, in intimate contact with osteoblasts beside the endosteum, at the edge of the bone marrow. We conclude that the HSC niche is composed of solitary cells and that adult bone marrow HSC are not clustered.


Subject(s)
Bone Marrow Cells/cytology , GATA2 Transcription Factor/genetics , GATA2 Transcription Factor/metabolism , Hematopoietic Stem Cells/cytology , Nerve Tissue Proteins/metabolism , Nuclear Proteins/metabolism , Animals , Ataxin-1 , Ataxins , Bone Marrow Cells/physiology , Cell Cycle/genetics , Cell Differentiation/genetics , Genes, Reporter , Green Fluorescent Proteins/analysis , Green Fluorescent Proteins/genetics , Hematopoietic Stem Cells/chemistry , Hematopoietic Stem Cells/metabolism , Mice , Mice, Mutant Strains , Nerve Tissue Proteins/genetics , Nuclear Proteins/genetics , Osteoblasts/cytology , Osteoblasts/metabolism , Promoter Regions, Genetic
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