Publications by authors named "Hiroshi Ashida"

Periodontitis, a chronic inflammatory disease of periodontal tissue, is often associated with a group of pathogenic bacteria known as the "red complex," including Tannerella forsythia (T. forsythia). Previous papers showed that T.

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Objectives: In recent years, there has been a notable increase in syphilis cases in Japan and Western countries. Syphilis, a classic sexually transmitted disease caused by treponemas, presents diagnostic challenges due to its diverse clinical manifestations. This study explores the diagnosis of syphilis in patients treated at our hospital.

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Article Synopsis
  • * Two cases highlighted in the report demonstrate that switching to BRAF and MEK inhibitors after initial treatment led to tumor shrinkage and one patient becoming a candidate for surgery, with manageable side effects.
  • * The study advocates for BRAF gene testing at diagnosis since it can help identify patients who might benefit from these targeted therapies, making outpatient treatment feasible and potentially improving outcomes for those with unresectable ATC.
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Background: Recurrent or metastatic squamous cell carcinoma of the head and neck (R/MHNSCC) is a challenging malignancy with a poor prognosis and limited treatment options. Nivolumab, an immune checkpoint inhibitor (ICI) targeting the programmed cell death/programmed cell death ligand 1 (PD-1/PD-L1) pathway, has emerged as a promising therapy for these patients. However, identifying biomarkers predictive of response to nivolumab remains critical for optimizing treatment strategies.

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  • Clinical studies indicate that the bacteria Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) is linked to aggressive periodontitis and may worsen rheumatoid arthritis (RA), although the underlying mechanisms remain unclear.
  • Research using a mice model showed that systemic infection with A. actinomycetemcomitans leads to arthritis progression through IL-1β secretion and immune cell infiltration, which is tied to the activation of caspase-11 in macrophages.
  • The study suggests that blocking this inflammasome activation can reduce arthritis symptoms, providing insight into the relationship between periodontitis infections and RA worsening.
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Perceiving verticality is crucial for accurate spatial orientation. Previous research has revealed that tilted scenes can bias verticality perception. Verticality perception bias can be represented as the sum of multiple periodic functions that play a role in the perception of visual orientation, where the specific factors affecting each periodicity remain uncertain.

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Two types of disruptive effects of irrelevant sound on visual tasks have been reported: the changing-state effect and the deviation effect. The idea that the deviation effect, which arises from attentional capture, is independent of task requirements, whereas the changing-state effect is specific to tasks that require serial processing, has been examined by comparing tasks that do or do not require serial-order processing. While many previous studies used the missing-item task as the nonserial task, it is unclear whether other cognitive tasks lead to similar results regarding the different task specificity of both effects.

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The Rotating Snakes illusion is a visual illusion where a stationary image elicits a compelling sense of anomalous motion. There have been recurring albeit anecdotal claims that the perception of illusory motion is more salient when the image consists of patterns with the combination of blue and yellow; however, there is limited empirical evidence that supports those claims. In the present study, we aimed to assess whether the Rotating Snakes illusion is more salient in its blue-yellow variation, compared to red-green and greyscale variations when the luminance of corresponding elements within the patterns were equated.

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Background: Transoral videolaryngoscopic surgery (TOVS) is widely used in Japan, and conventional two-dimensional (2D) endoscopic methods have been established. Three-dimensional (3D) endoscopic surgery offers superior distance perception because it provides stereoscopic views. Recently, we have developed 3D endoscopy for TOVS (3D TOVS).

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Buruli ulcer is an emerging chronic infectious skin disease caused by Mycobacterium ulcerans. Mycolactone, an exotoxin produced by the bacterium, is the only identified virulence factor so far, but the functions of this toxin and the mechanisms of disease progression remain unclear. By interfering Sec61 translocon, mycolactone inhibits the Sec61-dependent co-translational translocation of newly synthesized proteins, such as induced cytokines and immune cell receptors, into the endoplasmic reticulum.

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A movie taken from the front window of a running train, with zooming in and out, has been popularly acknowledged as a perceptual illusion such that the train motion is perceived as much slower when zoomed in. This is, however, not a real illusion because the image speed varies as a function of the focal length of the lens. This could be a meta-illusion, that is, an illusory sense of illusion, that might reflect a lack of understanding of how zooming changes the geometrical structure of the image.

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The intricate interplay between gut microbes and the onset of experimental autoimmune encephalomyelitis (EAE) remains poorly understood. Here, we uncover remarkable similarities between CD4 T cells in the spinal cord and their counterparts in the small intestine. Furthermore, we unveil a synergistic relationship between the microbiota, particularly enriched with the tryptophan metabolism gene EC:1.

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Background & Aims: D-amino acids, the chiral counterparts of protein L-amino acids, were primarily produced and utilized by microbes, including those in the human gut. However, little was known about how orally administered or microbe-derived D-amino acids affected the gut microbial community or gut disease progression.

Methods: The ratio of D- to L-amino acids was analyzed in feces and blood from patients with ulcerative colitis (UC) and healthy controls.

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Caspase activation results in pyroptosis, an inflammatory cell death that contributes to several inflammatory diseases by releasing inflammatory cytokines and cellular contents. Fusobacterium nucleatum is a periodontal pathogen frequently detected in human cancer and inflammatory bowel diseases. Studies have reported that F.

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The sense of body ownership, a feeling that one's body belongs to the self, is an essential aspect of self-consciousness. Studies have focused on emotions and bodily states that could influence multisensory integration for the sense of body ownership. Based on the Facial Feedback Hypothesis, the purpose of this study was to examine whether displaying specific facial expressions affects the rubber hand illusion.

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Since large eyes are often perceived to enhance facial attractiveness, many individuals are motivated to change their eyes' appearance. Colored contact lenses are often used by young women to darken the limbal rings of their irides, to increase their facial attractiveness. Among Westerners, wearing contact lenses with limbal rings enhances facial attractiveness; a similar effect might exist for East Asians whose irides are darker; although, the mechanism underlying these preferences in Westerners and East Asians might differ.

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Visual orientation plays an important role in postural control, but the specific characteristics of postural response to orientation remain unknown. In this study, we investigated the relationship between postural response and the subjective visual vertical (SVV) as a function of scene orientation. We presented a virtual room including everyday objects through a head-mounted display and measured head tilt around the naso-occipital axis.

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The gastrointestinal tract of the human body is characterized by a highly unique oxygenation profile, where the oxygen concentration decreases toward the lower tract, not found in other organs. The epithelial cells lining the mucosa where Helicobacter pylori resides exist in a relatively low oxygen environment with a partial pressure of oxygen (pO) below 58 mm Hg. However, the contribution of hypoxia to H.

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Article Synopsis
  • Long-term infection with Helicobacter pylori can lead to stomach cancer, but how the bacteria survive in the stomach is not well understood.
  • A small RNA called HPnc4160 helps H. pylori adapt and produce proteins that may cause cancer.
  • In experiments, bacteria without HPnc4160 were better at surviving in the stomach, and lower levels of this RNA were found in cancer patients compared to non-cancer patients.
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Increases in adhesive and invasive commensal bacteria, such as Escherichia coli, and subsequent disruption of the epithelial barrier is implicated in the pathogenesis of inflammatory bowel disease (IBD). However, the protective systems against such barrier disruption are not fully understood. Here, we show that secretion of luminal glycoprotein 2 (GP2) from pancreatic acinar cells is induced in a TNF-dependent manner in mice with chemically induced colitis.

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We investigated postural responses (head displacements) and self-motion perception (vection) to radial and lateral optic flows while sitting and standing by using a head-mounted display. We found that head displacement directions varied across postures. In the standing posture, radial optic flow generally produced the opposed head displacement against the perceived vection direction, consistent with the literature; however, in the sitting posture, the optic flow generally produced the following head displacement in the vection direction.

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In a stimulus with multiple moving elements, an observer may perceive that the whole stimulus moves in unison if (a) one can associate an element in one frame with one in the next (correspondence) and (b) a sufficient proportion of correspondences signal a similar motion direction (coherence). We tested the necessity of these two conditions by asking the participants to rate the perceived intensity of linear, concentric, and radial motions for three types of stimuli: (a) , in which the direction of each dot was randomly determined for each frame, (b) , which was a set of uncorrelated random dot images presented in sequence, and (c) , in which 35% of dots moved coherently. The participants perceived global motion not only in the global motion conditions but also in the random image sequences, though not in random walk motion.

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In response to bacterial infection, epithelial cells undergo several types of cell death, including apoptosis, necrosis, pyroptosis, and necroptosis, which serve to expel the infected cells and activate the innate and acquired immune responses. Shigella initially invades macrophages and subsequently surrounding enterocytes; the pathogen executes macrophage cell death but prevents epithelial cell death in order to maintain its foothold for replication. To this end, Shigella delivers versatile effector proteins via the type III secretion system (T3SS), allowing it to efficiently colonize the intestinal epithelium.

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Upon invasive bacterial infection of colonic epithelium, host cells induce several types of cell death to eliminate pathogens. For instance, necroptosis is a RIPK-dependent lytic cell death that serves as a backup system to fully eliminate intracellular pathogens when apoptosis is inhibited; this phenomenon has been termed "cell death crosstalk". To maintain their replicative niche and multiply within cells, some enteric pathogens prevent epithelial cell death by delivering effectors via the type III secretion system.

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