43 research outputs found

    Carbonation Behavior of Powdered Cement-Based Materials Under Different Relative Humidities and CO2 Concentrations

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    The aim of the current study is to investigate the carbonation behavior of cement hydrates at different environments. Hardened cement pastes are prepared using OPC and BFS and crushed into ~90μm powder. The powder samples are carbonated at 5/20% CO2 and at 60/85%RH. TGA, XRD and phenolphthalein tests are conducted before and after carbonation. The results show that CH remain uncarbonated even after CO2 uptake apparently ended and that the amount of the residual CH affects the results of phenolphthalein test. External humidity strongly affects the carbonation behavior of both CH and other hydrates. The degree of CH carbonation is greater at higher humidity, while the degree of other hydrates carbonation is greater at lower humidity. This conflicting effect can occur at surface of bulk concretes and changes in its properties (coarsening of pore structure and cracking) can be caused without apparent carbonation detected by phenol phthalein test. The effect of relative humidity on CSH carbonation should be taken into consideration when estimating long-term performance of carbonated concretes

    Differential expression of syndecan isoforms during mouse incisor amelogenesis

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    Syndecans are transmembranous heparan sulfate proteoglycans (HSPGs) with covalently attached glycosaminoglycan side-chains located on the cell surface. The mammalian syndecan family is composed of four types of syndecans (syndecan-1 to -4). Syndecans interact with the intracellular cytoskeleton through the cytoplasmic domains of their core proteins and membrane proteins, extracellular enzymes, growth factors, and matrix components, through their heparan-sulfate chains, to regulate developmental processes. Here, as a first step to assess the possible roles of syndecan proteins in amelogenesis, we examined the expression patterns of all syndecan isoforms in continuously growing mouse incisors, in which we can overview major differentiation stages of amelogenesis at a glance. Understanding the expression domain of each syndecan isoform during specific developmental stages seems useful for investigating their physiological roles in amelogenesis. Immunohistochemical analysis of syndecan core proteins in the lower incisors from postnatal day 1 mice revealed spatially and temporally specific expression patterns, with syndecan-1 expressed in undifferentiated epithelial and mesenchymal cells, and syndecan-2, -3, and -4 in more differentiated cells. These findings suggest that each syndecan isoform functions distinctly during the amelogenesis of the incisors of mice

    Difference in Serum Levels of Vitamin D Between Canalolithiasis and Cupulolithiasis of the Horizontal Semicircular Canal in Benign Paroxysmal Positional Vertigo

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    Background and Purpose: In the horizontal canal benign paroxysmal positional vertigo (BPPV), cupulolithiasis shows apogeotropic direction changing nystagmus lasting more than 1 min, while canalolithiasis leads to geotropic direction changing nystagmus lasting < 1 min. The difference between cupulolithiasis and canalolithiasis is widely accepted to be the attachment of the displaced otoconia to the cupula of a semicircular canal. Several studies have shown a relationship between BPPV and vitamin D deficiency, but no studies have compared serum levels of vitamin D between canalolithiasis and cupulolithiasis patients. The purpose of this study was to clarify the difference in vitamin D serum level between canalolithiasis and cupulolithiasis of the horizontal canal.Methods: This retrospective study included 20 and 15 patients with canalolithiasis and cupulolithiasis of the horizontal canal, respectively. Serum levels of 25-hydroxyvitamin D [25(OH)D] during the acute phase of BPPV were measured.Results: The mean 25(OH)D serum level in patients with canalolithiasis and cupulolithiasis was 13.2 ± 1.4 and 20.4 ± 1.6 ng/mL, respectively, and the difference was statistically significant (p = 0.0014), also after adjusting for age and sex (p = 0.0351). Eighteen out of 20 (90%) and 5 of 15 (33%) patients were diagnosed with vitamin D deficiency in the canalolithiasis and cupulolithiasis groups, respectively, and this difference was also statistically significant (p = 0.0005).Conclusion: We found that serum vitamin D level in patients with canalolithiasis was significantly lower than that in patients with cupulolithiasis of the horizontal canal

    Cutoff Values of Serum IgG4 and Histopathological IgG4+ Plasma Cells for Diagnosis of Patients with IgG4-Related Disease

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    IgG4-related disease is a new disease classification established in Japan in the 21st century. Patients with IgG4-related disease display hyper-IgG4-gammaglobulinemia, massive infiltration of IgG4+ plasma cells into tissue, and good response to glucocorticoids. Since IgG4 overexpression is also observed in other disorders, it is necessary to diagnose IgG4-related disease carefully and correctly. We therefore sought to determine cutoff values for serum IgG4 and IgG4/IgG and for IgG4+/IgG+ plasma cells in tissue diagnostic of IgG4-related disease. Patients and Methods. We retrospectively analyzed serum IgG4 concentrations and IgG4/IgG ratio and IgG4+/IgG+ plasma cell ratio in tissues of 132 patients with IgG4-related disease and 48 patients with other disorders. Result. Serum IgG4 >135  mg/dl demonstrated a sensitivity of 97.0% and a specificity of 79.6% in diagnosing IgG4-related disease, and serum IgG4/IgG ratios >8% had a sensitivity and specificity of 95.5% and 87.5%, respectively. IgG4+cell/IgG+ cell ratio in tissues >40% had a sensitivity and specificity of 94.4% and 85.7%, respectively. However, the number of IgG4+ cells was reduced in severely fibrotic parts of tissues. Conclusion. Although a recent unanimous consensus of all relevant researchers in Japan recently established the diagnostic criteria for IgG4-related disease, findings such as ours indicate that further discussion is needed

    Successful Treatment of Plasma Cell-Rich Acute Rejection Using Pulse Steroid Therapy Alone: A Case Report

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    Despite the recent development of immunosuppressive agents, plasma cell-rich acute rejection (PCAR) has remained refractory to treatment. Herein, we report an unusual case of PCAR that responded well to pulse steroid therapy alone. A 47-year-old man was admitted for a protocol biopsy three months after kidney transplantation, with a stable serum creatinine level of 1.6 mg/dL. Histological examination showed focal aggressive tubulointerstitial inflammatory cell infiltration of predominantly polyclonal mature plasma cells, leading to our diagnosis of PCAR. Three months following three consecutive days of high-dose methylprednisolone (mPSL) therapy, an allograft biopsy performed for therapy evaluation showed persistent PCAR. We readministered mPSL therapy and successfully resolved the PCAR. Although PCAR generally develops more than six months after transplantation, we diagnosed this case early, at three months after transplantation, with focally infiltrated PCAR. This case demonstrates the importance of early diagnosis and prompt treatment of PCAR to manage the development and severity of allograft rejection
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