Publications by authors named "Hirofumi Yamaguchi"

With dental implant treatment becoming the gold standard, the need for effective bone augmentation prior to implantation has grown. This study aims to evaluate a bone augmentation strategy integrating three key growth factors: bone morphogenetic protein-2 (BMP-2), insulin-like growth factor 1 (IGF-1), and vascular endothelial growth factor (VEGF). Collagen scaffolds incorporating BMP-2, IGF-1, or VEGF were fabricated and categorized into five groups based on their content: scaffold alone; BMP-2 alone (BMP-2); BMP-2 and IGF-1 (BI); BMP-2, IGF-1, and VEGF (BIV); and BMP-2 and IGF-1 with an earlier release of VEGF (BI + V).

View Article and Find Full Text PDF

Most reports on duplicate dentures are introduction to fabrication methods or clinical case reports. Only a few studies have verified their clinical effectiveness; hence, evidence to construct useful clinical guidelines for duplicate denture use is lacking. This review aimed to comprehensively investigate reports on duplicate dentures to accumulate evidences that will contribute to the formulation of clinical practice guidelines.

View Article and Find Full Text PDF
Article Synopsis
  • Alveolar osteitis (dry sockets) is a painful condition caused by the removal of blood clots from tooth extraction sites, leading to a poor immune response due to bacterial fermentation of food in the sockets.
  • This study investigated how short-chain fatty acids (SCFAs) produced by oral bacteria affect immune response and bone metabolism using mouse macrophages and bone cells.
  • The findings suggest that SCFAs from specific bacteria may reduce inflammation and slightly promote mineralization in the alveolar bone, enhancing our understanding of dry sockets.
View Article and Find Full Text PDF

Autophagy is a cellular mechanism that utilizes lysosomes to degrade its own components and is performed using Atg5 and other molecules originating from the endoplasmic reticulum membrane. On the other hand, we identified an alternative type of autophagy, namely, Golgi membrane-associated degradation (GOMED), which also utilizes lysosomes to degrade its own components, but does not use Atg5 originating from the Golgi membranes. The GOMED pathway involves Ulk1, Wipi3, Rab9, and other molecules, and plays crucial roles in a wide range of biological phenomena, such as the regulation of insulin secretion and neuronal maintenance.

View Article and Find Full Text PDF
Article Synopsis
  • Three-dimensional (3D) cell culture systems more closely mimic real physiological conditions compared to traditional two-dimensional (2D) models often used in periodontal research.
  • A new 3D gingival tissue model was created using human gingival epithelial Ca9-22 cells and primary gingival fibroblasts, incorporating both epithelial and connective tissue layers.
  • Treatment with butyrate, a metabolite from oral bacteria, led to epithelial cell death and the release of damage-associated molecular patterns, indicating potential implications for understanding tissue responses in oral health.
View Article and Find Full Text PDF

Objectives: The role of autophagy in pancreatic β cells has been reported, but the relationship between autophagy and insulin metabolism is complex and is not fully understood yet.

Design: We here analyze the relationship between autophagy and insulin metabolism from a morphological aspect.

Methods: We observe the morphological changes of β cell-specific Atg7-deficient mice and Atg5-deficient MIN6 cells with electron microscopy.

View Article and Find Full Text PDF

Two oval sandwich type magnetic attachments set up in various angulations and spacing, then the pattern of retentive force against horizontal displacement studied. A measuring device and methodology that matches ISO 13017 was used. A pair of magnetic attachments fixed on the same plane at a specific distance on the measuring device and set in various angulations.

View Article and Find Full Text PDF

Objectives: Oral bacteria may contribute to postoperative infectious complications including postoperative pneumonia or surgical site infection. The aim of this study was to investigate the impact of preoperative dental care on postoperative outcomes among surgical patients under general anesthesia.

Design: Retrospective cohort study.

View Article and Find Full Text PDF

As one of the great survivors of the plant kingdom, barnyard grasses (Echinochloa spp.) are the most noxious and common weeds in paddy ecosystems. Meanwhile, at least two Echinochloa species have been domesticated and cultivated as millets.

View Article and Find Full Text PDF

Alternative autophagy is an Atg5/Atg7-independent type of autophagy that contributes to various physiological events. We here identify Wipi3 as a molecule essential for alternative autophagy, but which plays minor roles in canonical autophagy. Wipi3 binds to Golgi membranes and is required for the generation of isolation membranes.

View Article and Find Full Text PDF

Various clinical and experimental findings have revealed the causal relationship between autophagy failure and oncogenesis, and several mechanisms have been suggested to explain this relationship. We recently proposed two additional mechanisms: centrosome number dysregulation and the failure of autophagic cell death. Here, we detail the mechanical relationship between autophagy failure and oncogenesis.

View Article and Find Full Text PDF

Binary Ti-Fe alloys with 5-25 mass% Fe were prepared, and subjected to reciprocating wear test. The aim of this study was to investigate the relationship between mechanical properties and the wear resistance of titanium and Ti-Fe alloys. The dimensions (length, width and depth) of wear marks on Ti-Fe alloys were less than those observed on pure Ti specimen.

View Article and Find Full Text PDF

Binary Ti-Fe alloys of varying concentrations of Fe between 5-25% were made, and their castings evaluated in terms of microstructures formed and mechanical properties. The aim of this study was to explore the composition of Ti-Fe alloys that offers improved wear resistance of titanium. X-ray diffraction and microstructural observation revealed that 5-7% Fe, 8-15% Fe, and 20-25% Fe consisted of α+β, single β, and β+Ti-Fe phases, respectively.

View Article and Find Full Text PDF

Alternative autophagy is an autophagy-related protein 5 (Atg5)-independent type of macroautophagy. Unc51-like kinase 1 (Ulk1) is an essential initiator not only for Atg5-dependent canonical autophagy but also for alternative autophagy. However, the mechanism as to how Ulk1 differentially regulates both types of autophagy has remained unclear.

View Article and Find Full Text PDF

Autophagy is a cellular process that degrades intracellular components, including misfolded proteins and damaged organelles. Many neurodegenerative diseases are considered to progress via the accumulation of misfolded proteins and damaged organelles; therefore, autophagy functions in regulating disease severity. There are at least two types of autophagy (canonical autophagy and alternative autophagy), and canonical autophagy has been applied to therapeutic strategies against various types of neurodegenerative diseases.

View Article and Find Full Text PDF

Background: Chronic obstructive pulmonary disease (COPD) and asthma have similar clinical features and are both exacerbated by airway infection.

Objective: To determine whether garenoxacin mesylate hydrate (GRNX) added to the standard care for bacterial infection-induced acute exacerbation of asthma or COPD in adults has clinical benefits.

Method: This single-arm clinical trial was conducted from January 2015 to March 2016.

View Article and Find Full Text PDF

Autophagy is an evolutionarily conserved process that degrades subcellular constituents. Mammalian cells undergo two types of autophagy; Atg5-dependent conventional autophagy and Atg5-independent alternative autophagy, and the molecules required for the latter type of autophagy are largely unknown. In this study, we analyzed the molecular mechanisms of genotoxic stress-induced alternative autophagy, and identified the essential role of p53 and damage-regulated autophagy modulator (Dram1).

View Article and Find Full Text PDF

Barnyardgrass (Echinochloa crus-galli) is a pernicious weed in agricultural fields worldwide. The molecular mechanisms underlying its success in the absence of human intervention are presently unknown. Here we report a draft genome sequence of the hexaploid species E.

View Article and Find Full Text PDF

ATG5 and ATG7 are considered to be essential molecules for the induction of autophagy. However, we found that cells lacking ATG5 or ATG7 can still form autophagosomes/autolysosomes and perform autophagic protein degradation when subjected to certain types of stress. Although the lipidation of LC3 is accepted as a good indicator of autophagy, this did not occur during ATG5/ATG7-independent alternative autophagy.

View Article and Find Full Text PDF

Acute stroke patients with dysphagia are at risk of developing pulmonary infection, which increases the risk of death. Therefore, optimal management of dysphagia is essential; however, available evidence supporting the effectiveness of dysphagia treatments is limited. Surface electrical stimulation (e-stim) has been developed as a new treatment modality for dysphagia.

View Article and Find Full Text PDF

Centrosome number is associated with the chromosome segregation and genomic stability. The ubiquitin-proteasome system is considered to be the main regulator of centrosome number. However, here we show that autophagy also regulates the number of centrosomes.

View Article and Find Full Text PDF

Autophagy is a cellular process that degrades subcellular constituents, and is conserved from yeast to mammals. Although autophagy is believed to be essential for living cells, cells lacking Atg5 or Atg7 are healthy, suggesting that a non-canonical degradation pathway exists to compensate for the lack of autophagy. In this study, we show that the budding yeast Saccharomyces cerevisiae, which lacks Atg5, undergoes bulk protein degradation using Golgi-mediated structures to compensate for autophagy when treated with amphotericin B1, a polyene antifungal drug.

View Article and Find Full Text PDF

Macroautophagy is a highly conserved intracellular process responsible for the degradation of subcellular constituents. Macroautophagy was recently suggested to be involved in the removal of mitochondria from reticulocytes during the final stage of erythrocyte differentiation. Although Atg5 and Atg7 are indispensable for macroautophagy, their role in mitochondrial clearance remains controversial.

View Article and Find Full Text PDF