Biogerontology
November 2024
Comparing transcriptome profiling between younger and older samples reveals genes related to aging and provides insight into the biological functions affected by aging. Recent research has identified sex, tissue, and cell type-specific age-related changes in gene expression. This study reports the overall picture of the opposite aging effect, in which aging increases gene expression in one cell subset and decreases it in another cell subset.
View Article and Find Full Text PDFGenome-wide association studies have enabled the identification of important genetic factors in many trait studies. However, only a fraction of the heritability can be explained by known genetic factors, even in the most common diseases. Genetic loci combinations, or epistatic contributions expressed by combinations of single nucleotide polymorphisms (SNPs), have been argued to be one of the critical factors explaining some of the missing heritability, especially in oligogenic/polygenic diseases.
View Article and Find Full Text PDFIdentification of genes whose expression increases or decreases with age is central to understanding the mechanisms behind aging. Recent scRNA-seq studies have shown that changes in single-cell expression profiles with aging are complex and diverse. In this study, we introduce a novel workflow to detect changes in the distribution of arbitrary monotonic age-related changes in single-cell expression profiles.
View Article and Find Full Text PDFBackground: Kidney transplantation is a well-established alternative in renal replacement therapy. Compared with hemodialysis, low-immunological-risk kidney transplantation can reduce the medical treatment costs associated with end-stage renal disease. However, there are few reports on whether high-immunological-risk kidney transplantation reduces the financial burden on governments.
View Article and Find Full Text PDFAssay for Transposase-Accessible Chromatin using high-throughput sequencing (ATAC-seq) is the popular technique using next-generation sequencing to measure chromatin accessibility and identify open chromatin regions. While read alignment shape information of next-generation sequencing data with intensity information has been used in various bioinformatics methods, few studies have focused on pure shape information alone. In this study, we investigated what types of ATAC-seq read alignment shapes are observed for the promoter region and whether the pure shape information was related or unrelated to other gene features.
View Article and Find Full Text PDFComput Struct Biotechnol J
October 2023
Gene sets are functional units for living cells. Previously, limited studies investigated the complex relations among gene sets, but documents about their altering patterns across biological conditions still need to be prepared. In this study, we adopted and modified a classical k-nearest neighbor-based association function to detect inter-gene-set similarities.
View Article and Find Full Text PDFDNA methylation clocks estimate biological age based on DNA methylation profiles. This study developed a mathematical model to describe DNA methylation aging and the establishment of a pan-tissue DNA methylation clock. The model simulates the aging dynamics of DNA methylation profiles based on passive demethylation as well as the process of cross-sectional bulk data acquisition.
View Article and Find Full Text PDFBiogerontology
February 2024
Plasma proteins serve as biomarkers of aging and various age-related diseases. While a number of plasma proteins have been identified that increase or decrease with age, the interpretation of each protein is challenging. This is due to the nature of plasma, which is a mixture of factors secreted by many different tissues and cells.
View Article and Find Full Text PDFAtrial fibrillation (AF) is the most frequent persistent arrhythmia. Many genes have been reported as a genetic background for AF. However, most transcriptome analyses of AF are limited to the atrial samples and have not been evaluated by multiple cardiac regions.
View Article and Find Full Text PDFBackground: Aging affects the incidence of diseases such as cancer and dementia, so the development of biomarkers for aging is an important research topic in medical science. While such biomarkers have been mainly identified based on the assumption of a linear relationship between phenotypic parameters, including molecular markers, and chronological age, numerous nonlinear changes between markers and aging have been identified. However, the overall landscape of the patterns in nonlinear changes that exist in aging is unknown.
View Article and Find Full Text PDFBackground: Differential expression analysis is a standard approach in molecular biology. For example, genes whose expression levels differ between diseased and non-diseased samples are considered to be associated with that disease. On the other hand, differential variability analysis focuses on the differences of the variances of gene expression between sample groups.
View Article and Find Full Text PDFThe heart is a significant organ in mammalian life, and the heartbeat mechanism has been an essential focus of science. However, few studies have focused on species differences. Accordingly, challenges remain in studying genes that have universal functions across species and genes that determine species differences.
View Article and Find Full Text PDFBackground: It has been hypothesized that women with significant pelvic organ prolapse (POP), particularly of the anterior vaginal wall, may have voiding dysfunction (VD). Although the VD mechanism due to cystocele is not fully understood, different vaginal compartments have rarely been closely examined. This study attempted to further elucidate the correlation between POP and VD through a new subgroup classification using cystoscopy.
View Article and Find Full Text PDFGenetic epidemiology is a rapidly advancing field due to the recent availability of large amounts of omics data. In recent years, it has become possible to obtain omics information at the single-cell level, so genetic epidemiological models need to be updated to integrate with single-cell expression data. In this perspective paper, we propose a cell population-based framework for genetic epidemiology in the single-cell era.
View Article and Find Full Text PDFComparing multiple single-cell expression datasets such as cytometry and scRNA-seq data between case and control donors provides information to elucidate the mechanisms of disease. We propose a completely data-driven computational biological method for this task. This overcomes the challenges of conventional cellular subset-based comparisons and facilitates further analyses such as machine learning and gene set analysis of single-cell expression datasets.
View Article and Find Full Text PDFAntibody-mediated rejection (ABMR) continues to be a major problem undermining the success of kidney transplantation. Acute ABMR of kidney grafts is characterized by neutrophil and monocyte margination in the tubular capillaries and by graft transcripts indicating NK cell activation, but the myeloid cell mechanisms required for acute ABMR have remained unclear. Dysregulated donor-specific antibody (DSA) responses with high antibody titers are induced in B6.
View Article and Find Full Text PDFHuman immune systems are very complex, and the basis for individual differences in immune phenotypes is largely unclear. One reason is that the phenotype of the immune system is so complex that it is very difficult to describe its features and quantify differences between samples. To identify the genetic factors that cause individual differences in whole lymphocyte profiles and their changes after vaccination without having to rely on biological assumptions, we performed a genome-wide association study (GWAS), using cytometry data.
View Article and Find Full Text PDFOmics studies attempt to extract meaningful messages from large-scale and high-dimensional data sets by treating the data sets as a whole. The concept of treating data sets as a whole is important in every step of the data-handling procedures: the pre-processing step of data records, the step of statistical analyses and machine learning, translation of the outputs into human natural perceptions, and acceptance of the messages with uncertainty. In the pre-processing, the method by which to control the data quality and batch effects are discussed.
View Article and Find Full Text PDFSingle-cell expression analysis is an effective tool for studying the dynamics of cell population profiles. However, the majority of statistical methods are applied to individual profiles and the methods for comparing multiple profiles simultaneously are limited. In this study, we propose a nonparametric statistical method, called Decomposition into Extended Exponential Family (DEEF), that embeds a set of single-cell expression profiles of several markers into a low-dimensional space and identifies the principal distributions that describe their heterogeneity.
View Article and Find Full Text PDFPurpose: To investigate the clinical prognostic value of red cell distribution width (RDW) in patients with non-muscle-invasive bladder cancer (NMIBC).
Materials And Methods: We retrospectively evaluated 582 consecutive patients with primary NMIBC. The efficacy of preoperative RDW at predicting treatment outcome was assessed.
Background: The purpose of this study was to investigate whether adding single immediate postoperative intravesical instillation of doxorubicin (SID) to transurethral resection of bladder tumor (TURBT) significantly reduced the risk of recurrence in patients with non-muscle-invasive bladder cancer (NMIBC).
Materials And Methods: We retrospectively analyzed the records of 720 patients diagnosed with primary NMIBC between 2002 through 2018 at the Kameda Medical Center. The primary outcome measure was time to recurrence.
Objective: To investigate the 10-year biopsy-proven recurrence rates and risk factors for immunoglobulin A nephropathy recurrence in kidney transplant recipients.
Methods: We included 299 kidney transplant recipients from 1995 to 2015, who had biopsy-proven underlying immunoglobulin A nephropathy and underwent zero-hour biopsy. The primary end-point was recurrence of immunoglobulin A nephropathy.