Publications by authors named "Shiro Takahara"

Article Synopsis
  • The study explores the measurement of glomerular filtration rate (GFR), suggesting that the rare amino acids d-serine and d-asparagine can provide a more accurate assessment than traditional urine collection methods.
  • A cross-sectional analysis involving 209 kidney transplant donors and recipients utilized urine levels of these amino acids to establish an equation for estimating urine volume (eUV), which helped correct GFR measurements.
  • Results showed that d-serine and d-asparagine clearances had less bias compared to creatinine, highlighting their potential for improving GFR estimations and urine volume assessments.
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D-Alanine, a rare enantiomer of alanine, can potentially alleviate the worsening of viral infections and maintain circadian rhythm. This study aimed to analyze the kinetics of D-Alanine upon oral intake. Five healthy volunteers were administered D-Alanine as a single oral dose at 11,236 or 33,708 µmoL (1-3 g).

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Article Synopsis
  • Current screening tools for urothelial carcinoma (UC) are not effective, especially during early stages of the disease.
  • A study discovered that serum d-asparagine levels are significantly higher in UC patients, leading to the development of a new blood-based diagnostic equation combining d-asparagine levels and estimated glomerular filtration rate (eGFR).
  • This new screening method shows promising results, with a high accuracy (AUC-ROC of 0.869), and significantly improves diagnosis when used alongside urinary tests.
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  • Solid organ transplant (SOT) recipients show poor antibody production against SARS-CoV-2 post-vaccination, raising concerns about their immune responses.
  • A study involving 614 SOT recipients vaccinated with mRNA vaccines revealed an overall seropositivity rate of 43% one month after the second dose, increasing to 70% by six months.
  • Kidney, lung, and simultaneous pancreas-kidney transplant recipients had lower antibody levels at 3 and 6 months compared to other organ types, indicating slower antibody acquisition relative to the general population.
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Article Synopsis
  • The study focuses on comparing the immunogenicity of the COVID-19 vaccines BNT162b2 and mRNA1273 in solid organ transplant (SOT) recipients who are on immunosuppressive medication.
  • A total of 623 SOT recipients participated, with a final analysis comparing 100 participants who received each vaccine.
  • Results showed that mRNA1273 had significantly better immunogenicity compared to BNT162b2, particularly noticeable 3 months after the second dose.
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Introduction: An ideal endogenous molecule for measuring glomerular filtration rate (GFR) is still unknown. However, a rare enantiomer of serine, d-serine, is useful in GFR measurement. This study explored the potential of other d-amino acids for kidney function assessment.

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Article Synopsis
  • * A 62-year-old male kidney transplant recipient experienced high fever, diarrhea, and cough, leading to a rapid decline in kidney function and a positive COVID-19 test.
  • * After stopping mycophenolate mofetil and starting treatments like sotrovimab and remdesivir, the patient's clinical symptoms and renal function showed gradual improvement, despite significant kidney damage from severe acute tubular necrosis.
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Background: The diagnosis of diabetic nephropathy (DN), the major cause of ESKD, requires kidney biopsy. d-Serine, present only in trace amounts in humans, is a biomarker for kidney diseases and shows potential to distinguish the origin of kidney diseases, whose diagnoses usually require kidney biopsy. We extended this concept and examined the potential of d-serine in the diagnosis of DN.

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Background: Endogenous molecules that provide an unbiased and a precise evaluation of kidney function are still necessary. We explored the potential of clearance of d-serine, a rare enantiomer of serine and a biomarker of kidney function, as a measure of glomerular filtration rate (GFR).

Methods: This was a cross-sectional observational study of 200 living kidney transplant donors and recipients enrolled between July 2019 and December 2020 in a single Japanese center, for whom GFR was measured by clearance of inulin (C-in).

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Although intensity-modulated radiation therapy (IMRT) has been developed as an alternative to conventional radiotherapy, reducing bone marrow damage is limited. Thus, a novel technology is needed to further mitigate IMRT-induced bone marrow damage. Molecular hydrogen (H) was recently reported as a preventive and therapeutic antioxidant that selectively scavenges hydroxyl radical (·OH) and peroxynitrite (ONOO).

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Anemia and vitamin D deficiency are associated with allograft failure, and hence, are potential therapeutic targets among kidney transplant recipients (KTRs). We conducted a multicenter, two-by-two factorial, open-label, randomized clinical trial to examine the effects of anemia correction and vitamin D supplementation on 2-year change in eGFR among KTRs (CANDLE-KIT). We enrolled 153 patients with anemia and >1-year history of transplantation across 23 facilities in Japan, and randomly assigned them to either a high or low hemoglobin target (>12.

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Background: Antibody-mediated rejection (AMR) is a crucial barrier in the long-term prognosis of transplant recipients.

Methods: Peripheral blood mononuclear cells (PBMCs) were collected from kidney allograft recipients ( = 41) and cultured in vitro for 1 week. Furthermore, the supernatants of the cultured PBMCs were analyzed by Luminex single-antigen beads.

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Separate assessment of mineral bone disorder (MBD) parameters including calcium, phosphate, parathyroid hormone (PTH), fibroblast growth factor 23 (FGF23), 25-hydroxyvitamin D, and 1,25-dihydroxyvitamin D (1,25D) predict renal outcomes in kidney transplant recipients (KTRs), with conflicting results. To date, data simultaneously evaluating these parameters and interwoven relations on renal outcomes are scarce. We conducted a prospective long-term follow-up cohort study included 263 KTRs with grafts functioning at least 1 year after transplantation.

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Background: Among Organisation for Economic Co-operation and Development countries, the number of cadaveric donors per population is the lowest in Japan. The present study investigated whether a continuing educational intervention for medical staff, such as Donor Action Program (DAP) that is aimed at increasing the number of cadaveric donors, improved the confirmation rate of organ donation in potential donors.

Material And Methods: We studied 2 hospitals with emergency centers in Toyama, Japan.

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Background: Immunosuppressive therapy for renal allograft recipients has changed substantially since the introduction of the anti-CD25 monoclonal antibody, basiliximab. We hypothesized that recent improvements in immunosuppressive treatment may reduce the incidence of osteonecrosis of the femoral head (ONFH). This study aimed to investigate transitional changes in the incidence of OFNH among renal transplant recipients by MRI.

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Acute graft-versus-host disease (aGvHD) remains lethal, even after allogeneic hematopoietic stem cell transplantation. Inflammatory responses play an important role in aGvHD. Salvianolic acid B (Sal B) has been widely reported to have a major effect on the anti-inflammatory response, but these effects in an aGvHD model have never been reported.

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Objective: To investigate the utility of estimated glomerular filtration rate for assessing kidney function in living kidney donors before and after nephrectomy.

Methods: A total of 101 donors underwent inulin clearance measurements before and 1 year after nephrectomy. The mean of three inulin clearance values was used as the measured glomerular filtration rate.

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Fatty liver has lower tolerance against ischemia-reperfusion (I/R) injury in liver operations, including liver transplantation. Seeking to ameliorate liver injury following I/R in fatty liver, we examined the protective effect of hydrogen (H) saline on I/R liver injury in a methionine and choline-deficient plus high fat (MCDHF) diet-induced fatty liver mouse model. Saline containing 7 ppm H was administrated during the process of I/R.

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In deceased donors, Ischemia/Reperfusion Injury (IRI) is an important cause of allograft dysfunction. Prolonged cold and warm ischemia time leads to a high risk of early post-transplant complications, including acute and chronic rejection. Ischemia not only up-regulates inflammatory cytokines and chemokines, but also enhances the expression of MHC-class II and adhesion molecules on epithelial and dendritic cells.

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Background: High-dose IVIG (2 g/kg) alone or low-dose IVIG (100 mg/kg) in conjunction with plasma exchange is typically administered as a renal transplantation desensitization therapy. Herein, we monitored changes in T cell and B cell flow cytometry crossmatch (FCXM) to assess the effects of short-term super high-dose IVIG (4 g/kg) administration with plasmapheresis before living-donor renal transplantation.

Methods: Seventeen patients, each showing positive T cell FCXM (median ratio, ≥ 1.

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Bacterial translocation is a major cause of multiple organ dysfunction syndrome in critical illness, and its management is an important therapeutic strategy. In this study, we focused on the key factors responsible for bacterial translocation including the intestinal microbiome and investigated the impact of molecular hydrogen therapy as a countermeasure against bacterial translocation in a murine model of sepsis. The experimental protocols were divided into the sham, saline treatment (control), and hydrogen treatment (H2) groups.

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Background: Medullary cystic kidney disease Type 1 is an autosomal dominant tubulointerstitial kidney disease (ADTKD). Recently, mucin 1 (MUC1) was identified as a causal gene of medullary cystic kidney disease (ADTKD-MUC1). However, the MUC1 mutation was found to be a single cytosine insertion in a single copy of the GC-rich variable number of tandem repeats (VNTRs), which are very difficult to analyze by next-generation sequencing.

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Steatosis has a low tolerance against ischemia-reperfusion injury (IRI). To prevent IRI in the steatotic liver, we attempted to elucidate the protective effect of astaxanthin (ASTX) in the steatotic liver model by giving mice a methionine and choline-deficient high fat (MCDHF) diet. Levels of lipid peroxidation and apoptosis, the expression of inflammatory cytokines and heme oxygenase (HO)-1, in the liver were assessed.

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Autosomal recessive polycystic kidney disease (ARPKD) is an important childhood nephropathy, occurring 1 in 20,000 live births. The major clinical phenotypes are expressed in the kidney with dilatation of the collecting ducts, systemic hypertension, and progressive renal insufficiency, and in the liver with biliary dysgenesis, portal tract fibrosis, and portal hypertension. The systemic hypertension has been attributed to enhanced distal sodium reabsorption in the kidney, the structural defects have been ascribed to altered cellular morphology, and fibrosis to increased TGF-β signaling in the kidney and biliary tract, respectively.

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