Publications by authors named "Ayaka Hayashi"

Oxidation of a thioether linkage in thioether-closed macrocyclic peptides led to collision-induced site-selective linearization of the peptides. This method has allowed for sequencing of thioether macrocyclic peptides. The utility of the sequencing method was demonstrated by identifying the correct peptide sequences from a virtually randomized thioether macrocyclic peptide library.

View Article and Find Full Text PDF

The humoral response of kidney transplant recipients (KTR) to the mRNA vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is generally poor. We evaluated the booster effect of the third dose (D3) of two SARS-CoV-2 mRNA vaccines 6 months after the second dose (D2) in Japanese KTR. The anti-spike (anti-S) antibody titer 1 and 3 months after the D3 was evaluated in 82 Japanese KTR.

View Article and Find Full Text PDF

Introduction: In kidney transplant recipients (KTRs) whose primary disease is IgA nephropathy (IgAN), IgAN recurrence occurs in approximately half of patients by 5 years postoperatively and is associated with graft survival. Although the alternative and lectin pathways are important in the primary pathogenesis of IgAN, the significance of mesangial C1q deposition, which triggers the classical pathway, is unknown. We investigated the clinicopathological significance of mesangial C1q deposition in both recurrent IgAN in KTRs and native IgAN.

View Article and Find Full Text PDF

Although mRNA vaccines for COVID-19 are highly beneficial and are recommended for patients with kidney disease, adverse reactions in some patients after vaccination have been problematic. Various vasculitis and renal disorders have been reported after vaccination; however, a causal relationship has not yet been identified. In this report, we describe a case of rapidly progressive glomerulonephritis that developed after SARS-CoV-2 vaccination, in which both anti-glomerular basement membrane (anti-GBM) and myeloperoxidase antineutrophil cytoplasmic antibodies (MPO-ANCA) were present.

View Article and Find Full Text PDF

The three primary sites of acute T-cell-mediated rejection (TCMR) in transplanted kidneys are the tubular epithelial cells, interstitium, and the vascular endothelial cells. The pathology of acute lesions is characterized by inflammatory cell infiltration; the final diagnosis suggested by the Banff 2019 classification is guided by grading of tubulitis (the t score), interstitial inflammation (the i score), and endarteritis (the v score). Consistent major issues when using the Banff classification are the etiological classifications of interstitial fibrosis and tubular atrophy (IFTA).

View Article and Find Full Text PDF

Study Objectives: To describe the outcomes of central sleep apnea requiring home supplemental oxygen therapy in otherwise healthy term infants.

Methods: All children < 1 year of age undergoing polysomnography between 2015 and 2020 at the Queensland Children's Hospital were retrospectively studied. Children with gestational age < 37 weeks, underlying syndrome, cleft palate, those with obstructive apnea-hypopnea index > 50% of total apnea-hypopnea index, or with underlying cardiac or pulmonary parenchymal pathology were excluded.

View Article and Find Full Text PDF

Background: A positive flow-cytometry T cell crossmatch (FTXM) has important prognostic implications, even when the complement-dependent cytotoxicity crossmatch is negative. Recent studies have shown that ABO incompatibility is associated with positive FTXM, but the underlying mechanism remains poorly understood.

Cases: In five ABO blood type O recipients of kidneys from wives with type B, FTXM was positive but complement-dependent cytotoxicity crossmatch was negative.

View Article and Find Full Text PDF

Background: DNA methylation is a significant epigenetic modification that is evolutionarily conserved in various species and often serves as a repressive mark for transcription. DNA methylation levels and patterns are regulated by a balance of opposing enzyme functions, DNA methyltransferases, DNMT1/3A/3B and methylcytosine dioxygenases, TET1/2/3. In mice, the TET enzyme converts DNA cytosine methylation (5mC) to 5-hydroxymethylcytosine (5hmC) at the beginning of fertilisation and gastrulation and initiates a global loss of 5mC, while the 5mC level is increased on the onset of cell differentiation during early embryonic development.

View Article and Find Full Text PDF

Human adult hepatocytes expressing CYP3A4, a major cytochrome P450 enzyme, are required for cell-based assays to evaluate the potential risk of drug-drug interactions caused by transcriptional induction of P450 enzymes in early-phase drug discovery and development. However, CYP3A7 is preferentially expressed in premature hepatoblasts and major hepatic carcinoma cell lines. The human hepatocellular carcinoma cell line HepaRG possesses a high self-renewal capacity and can differentiate into hepatic cells similar to human adult hepatocytes in vitro.

View Article and Find Full Text PDF