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17 results on '"Takafumi Morita"'

1. Kidney Veno-Muscular Characteristics and Kidney Disease Progression: A Native Kidney-Biopsy Study

Author

Kenji Tsuji, Hiroyuki Nakanoh, Kensaku Takahashi, Takafumi Morita, Yizhen Sang, Kazuhiko Fukushima, Natsumi Matsuoka-Uchiyama, Yasuhiro Onishi, Haruhito A. Uchida, Shinji Kitamura, and Jun Wada

Subjects
Veno-muscular complex, kidney pathology, kidney biopsy, interstitial fibrosis/tubular atrophy, inflammation, Diseases of the genitourinary system. Urology, RC870-923
Abstract

Rationale & Objective: Assessment of kidney biopsies provides crucial information for diagnosis and disease activity, as well as prognostic value. Kidney-biopsy specimens occasionally contain veno-muscular complex (VMC), which consists of muscle tissues around the kidney venous system in the corticomedullary region. However, the role of VMC and the clinical significance of VMC variants are poorly understood. In the present study, we investigated kidney prognostic values of VMC variants. Study Design: Retrospective cohort study. Setting & Participants: Among 808 patients who underwent a kidney biopsy from 2011 to 2019, 246 patients whose kidney biopsy specimens contained VMC were enrolled. Predictors: VMC variants; inflammatory-VMC (an infiltration of ≥80 inflammatory cells/mm2-VMC area) and VMC hypertrophy (hyper-VMC, a VMC average width ≥850 μm), and the interstitial fibrosis/tubular atrophy (IFTA) score. Outcomes: A decline in estimated glomerular filtration rate (eGFR) ≥40% from the baseline or commencement of kidney replacement therapy. Analytical Approach: Cox proportional hazards model. Results: Among 246 patients with data on VMC, mean baseline eGFR was 56.0±25.6 ml/min per 1.73 m2; 80 had high inflammatory-VMC, and 62 had VMC hypertrophy. There were 51 kidney events over median follow-up of 2.5 years. We analyzed 2 VMC variants. Multivariable logistic regression analysis revealed that eGFR negatively correlated with the presence of both inflammatory-VMC and hyper-VMC. A Cox proportional hazards analysis revealed that inflammatory-VMC (but not hyper-VMC) was independently associated with the primary outcome after adjustments for known risk factors of progression, including proteinuria, eGFR, and the interstitial fibrosis/tubular atrophy (IFTA) score (hazard ratio, 1.97; 95% confidence interval, 1.00-3.91). Limitations: Single-center study and small sample size. Conclusions: Assessment of inflammatory-VMC provides additional kidney prognostic information to known indicators of kidney disease progression in patients who undergo kidney biopsy. Plain-Language Summary: Assessment of kidney biopsies provides crucial information for diagnosis, disease activity, and prognostic value. Kidney-biopsy specimens occasionally contain veno-muscular complex (VMC), which consists of muscle tissues around the kidney venous system. Currently, the role of VMC in kidney health and diseases and the clinical significance of VMC variants are poorly understood. In the present study, we have shown that an infiltration of ≥80 inflammatory cells/mm2-VMC area (inflammatory-VMC) is independently associated with kidney disease progression after adjustments for known risk factors of progression. Therefore, assessment of inflammatory-VMC provides additional kidney prognostic information to known indicators of kidney disease progression in patients who undergo kidney biopsy.

Published
2023
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12. Electrochemical Quartz Crystal Microbalance Analysis of Nitrogen Oxide-Promoted Platinum Dissolution in HClO4

Author

Akira Eguchi, Takafumi Morita, Shin-ichiro Imabayashi, and Hironori Kuroe

Subjects
Oxide, Analytical chemistry, Quartz resonator, Quartz crystal microbalance, Electrochemistry, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Platinum dissolution, chemistry.chemical_compound, General Energy, chemistry, Nitrogen oxide, Physical and Theoretical Chemistry, Dissolution
Abstract

To elucidate the mechanism of NaNO2-promoted Pt dissolution, the weight loss of Pt black-deposited Au quartz resonators was measured in 0.1 mol dm–3 HClO4 containing NaNO2 under potential cycling and constant potential conditions. A continuous weight loss of ca. 50–60 ng cm–2 cycle–1 was detected in the presence of 10 mmol dm–3 NaNO2 during potential cycling above a high potential limit of 1.2 V vs RHE (VRHE) and below a low potential limit (EL) of 0.9 VRHE. A weight loss was observed at constant potentials (0.6–0.8 VRHE) when oxides were initially present; the net weight loss (Δw) magnitude increased as the amount of the initially formed Pt oxide increased. These results indicate that Pt dissolution occurred when Pt oxides were reduced in the presence of NaNO2. The good agreement between the Δw per potential cycle and the Δw at a constant potential (EL of the potential cycling = constant potential) revealed that the formation of Pt oxides in the positive sweep was required for the continuous weight loss ...

Published
2014
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13. Platinum Dissolution in Nitrogen Oxides-Containing HClO4 Solution Studied by Electrochemical Quartz Crystal Microbalance

Author

Takafumi Morita, Hironori Kuroe, Yuki Uchiyama, Tomohiro Abe, and Shin-ichiro Imabayashi

Subjects
Platinum dissolution, Thesaurus (information retrieval), Chemical substance, Materials science, Magazine, law, Inorganic chemistry, Quartz crystal microbalance, Science, technology and society, Electrochemistry, Nitrogen oxides, law.invention
Abstract

Platinum (Pt) dissolution has been elucidated by measuring a mass loss of Pt black-deposited Au quartz resonators in 0.1 mol dm-3 HClO4 containing NaNO2. A continuous weight loss of ca. 50 ng cm-2 cycle-1 was detected at [NaNO2] = 0.01 mol dm-3 under the potential cycling between 0.6 and 1.4 V vs. RHE. The magnitude of Pt dissolution depends on the concentration of NaNO2 and the range of potential cycling. The average mass loss decreases to 5~10 ng cm-2 cycle-1 at [NaNO2] = 1 mmol dm-3. The Pt dissolution occurs when the higher potential limit is more than 1.0 V vs. RHE and the lower potential limit is less than 0.9 V vs. RHE, suggesting that the reduction of Pt oxide in the presence of NaNO2 in the bulk solution contributes to the dissolution.

Published
2013
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15. A case of placenta accreta complicated by severe IUGR and maternal coagulopathy

Author

Toyohiro Ohta, Atsuo Itakura, Takashi Mitsui, Mayumi Okada, Mami Nomura, and Takafumi Morita

Subjects
Gynecology, Adult, medicine.medical_specialty, Fetal Growth Retardation, business.industry, Placenta accreta, Obstetrics, medicine.medical_treatment, Obstetrics and Gynecology, General Medicine, Placenta Accreta, Blood Coagulation Disorders, medicine.disease, Embolization, Therapeutic, Fetus, Pregnancy, medicine, Coagulopathy, Humans, Female, Embolization, business, Complication, Fetal Death, Placenta Diseases
Published
2007

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