32 research outputs found
Synthesis of a Peptide-Human Telomere DNA Conjugate as a Fluorometric Imaging Reagent for Biological Sodium Ion
A peptide-oligonucleotide conjugate (1) was synthesized by the attachment of FAM, TAMRA, and biotin moieties to a telomere DNA sequence of 5′-TAG GGT TAG GGT TAG GGT TAG GG-3′. This conjugate was induced to be an anti-parallel structure in the presence of sodium ion (Na+), whereas a hybrid one was formed under potassium ion (K+) as a monitoring by circular dichromic spectra. The conformation change of this conjugate gave an effective FRET signal change upon the addition of NaCl, compared with the case of KCl. Under 5 mM KCl as an extracellular condition, a FRET change was observed upon addition of NaCl and quantitative FRET change was observed in 0 – 250 mM NaCl. This conjugate was immobilized on the cell surface through a sugar chain on the cell, biotinyl concanavallin A and streptavidin. This conjugate was utilized for Na+ sensing based on anti-parallel tetraplex formation with Na+
Identification of a novel heterozygous mutation of the Aggrecan gene in a family with idiopathic short stature and multiple intervertebral disc herniation
Aggrecan is a critical proteoglycan component of the extracellular matrix of the growth plates and articular cartilage and has a key role in the biophysical and biomechanical properties of cartilage. Recently, heterozygous mutations in the ACAN gene, which encodes aggrecan, have been identified in patients with short stature and accelerated bone age. We herein report another family with a heterozygous ACAN mutation associated with idiopathic short stature along with accelerated bone age and early-onset herniation of the lumbar discs at the levels of L1/2 through L5/S1. Whole-exome sequencing identified a novel heterozygous frameshift mutation in the ACAN gene (c.1744delT; p.Phe582fs*69) in all of the affected family members but not in the unaffected one, providing further evidence that ACAN haploinsufficiency causes short stature with advanced bone maturation. In addition, we advocate early-onset multiple disc herniation as a novel phenotype associated with ACAN haploinsufficiency
Comparison of the Pulmonary Oxidative Stress Caused by Intratracheal Instillation and Inhalation of NiO Nanoparticles when Equivalent Amounts of NiO Are Retained in the Lung
NiO nanoparticles were administered to rat lungs via intratracheal instillation or inhalation. During pulmonary toxicity caused by NiO nanoparticles, the induction of oxidative stress is a major factor. Both intratracheal instillation and inhalation of NiO nanoparticles induced pulmonary oxidative stress. The oxidative stress response protein, heme oxygenase-1 (HO-1), was induced by the administration of NiO nanoparticles at both the protein and gene expression level. Additionally, certain oxidative-stress markers in the lung, such as 8-iso-prostaglandin F2α, thioredoxin, and inducible nitric oxide synthase were increased. Furthermore, the concentration of myeloperoxidase (MPO) in the lung was also increased by the administration of NiO nanoparticles. When the amount of NiO in the lung is similar, the responses against pulmonary oxidative stress of intratracheal instillation and inhalation are also similar. However, the state of pulmonary oxidative stress in the early phase was different between intratracheal instillation and inhalation, even if the amount of NiO in the lung was similar. Inhalation causes milder oxidative stress than that caused by intratracheal instillation. On evaluation of the nanoparticle-induced pulmonary oxidative stress in the early phase, we should understand the different states of oxidative stress induced by intratracheal instillation and inhalation
Assessment of Pulmonary Toxicity Induced by Inhaled Toner with External Additives
We investigated the harmful effects of exposure to a toner with external additives by a long-term inhalation study using rats, examining pulmonary inflammation, oxidative stress, and histopathological changes in the lung. Wistar rats were exposed to a well-dispersed toner (mean of MMAD: 2.1 μm) at three mass concentrations of 1, 4, and 16 mg/m3 for 22.5 months, and the rats were sacrificed after 6 months, 12 months, and 22.5 months of exposure. The low and medium concentrations did not induce statistically significant pulmonary inflammation, but the high concentration did, and, in addition, a histopathological examination showed fibrosis in the lung. Although lung tumor was observed in one sample of high exposure for 22.5 months, the cause was not statistically significant. On the other hand, a persistent increase in 8-OHdG was observed in the high exposure group, indicating that DNA damage by oxidative stress with persistent inflammation leads to the formation of tumorigenesis. The results of our studies show that toners with external additives lead to pulmonary inflammation, oxidative stress, and fibrosis only at lung burdens beyond overload. These data suggest that toners with external additives may have low toxicity in the lung
Synthesis of a Peptide-Human Telomere DNA Conjugate as a Fluorometric Imaging Reagent for Biological Sodium Ion
A peptide-oligonucleotide conjugate (1) was synthesized by the attachment of FAM, TAMRA, and biotin moieties to a telomere DNA sequence of 5′-TAG GGT TAG GGT TAG GGT TAG GG-3′. This conjugate was induced to be an anti-parallel structure in the presence of sodium ion (Na+), whereas a hybrid one was formed under potassium ion (K+) as a monitoring by circular dichromic spectra. The conformation change of this conjugate gave an effective FRET signal change upon the addition of NaCl, compared with the case of KCl. Under 5 mM KCl as an extracellular condition, a FRET change was observed upon addition of NaCl and quantitative FRET change was observed in 0 – 250 mM NaCl. This conjugate was immobilized on the cell surface through a sugar chain on the cell, biotinyl concanavallin A and streptavidin. This conjugate was utilized for Na+ sensing based on anti-parallel tetraplex formation with Na+
Evaluation of Pulmonary Toxicity of Zinc Oxide Nanoparticles Following Inhalation and Intratracheal Instillation
We conducted inhalation and intratracheal instillation studies of zinc oxide (ZnO) nanoparticles in order to examine their pulmonary toxicity. F344 rats were received intratracheal instillation at 0.2 or 1 mg of ZnO nanoparticles with a primary diameter of 35 nm that were well-dispersed in distilled water. Cell analysis and chemokines in bronchoalveolar lavage fluid (BALF) were analyzed at three days, one week, one month, three months, and six months after the instillation. As the inhalation study, rats were exposed to a concentration of inhaled ZnO nanoparticles (2 and 10 mg/m3) for four weeks (6 h/day, 5 days/week). The same endpoints as in the intratracheal instillation study were analyzed at three days, one month, and three months after the end of the exposure. In the intratracheal instillation study, both the 0.2 and the 1.0 mg ZnO groups had a transient increase in the total cell and neutrophil count in the BALF and in the expression of cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-2, chemokine for neutrophil, and heme oxygenase-1 (HO-1), an oxidative stress marker, in the BALF. In the inhalation study, transient increases in total cell and neutrophil count, CINC-1,-2 and HO-1 in the BALF were observed in the high concentration groups. Neither of the studies of ZnO nanoparticles showed persistent inflammation in the rat lung, suggesting that well-dispersed ZnO nanoparticles have low toxicity