Submarine lava flow emplacement and faulting in the axial valley of two morphologically distinct spreading segments of the Mariana back-arc basin from Wadatsumi side-scan sonar images

International audienceHigh-resolution, deep-tow side-scan sonar data were collected over two distinct spreading segments in the central part of the Mariana back-arc basin. These data allow mapping of small fissures and faults and the distinguishing of hummocky from smooth lava flows. Using these data, we observe spatial variations in seafloor deformation and volcanic activity within each segment, and also significant differences in the degree of tectonic deformation between the two segments. One segment, characterized by an hourglass shape suggestive of magmatic processes dominating over tectonic processes, is in fact currently dominated by intense deformation rather than volcanism. The other segment, which exhibits morphology (wide and deep linear axial valley) typical of magma-starved segments, is subjected to very limited deformation and is covered by mostly unfaulted, recent flows. Each segment also displays along-axis variations in the degree of tectonic deformation and in lava flows freshness. We observe a decrease of lava effusion rate from segment centers toward their ends. We also investigated the apparent asymmetry of the Mariana basin. On the southern segment of the study area, azimuths of tectonic structures are divided into two groups, one segment-parallel and one ∼15° oblique to strike of the segment. These two trends of linear features developed synchronously with volcanic activity. Currently oblique structures seem to be the most active ones. The tectonic structures that are parallel to the overall valley trend are distributed over the entire valley, whereas the oblique structures are only located proximal to the eastern valley wall. They are likely related to changes in the local stress field related to the obliquely trending eastern axial valley wall. Asymmetric character, such as nonuniform spacing and throw of faults, was not observed. These observations suggest that the asymmetry of the basin is not due to asymmetric spreading, but rather to eastward ridge jumps of several kilometers. Such small-amplitude ridge jumps likely occurred frequently during basin development because the asymmetric character of the basin is strongly pronounced and no abandoned rift valley is recognizable within the entire basi

胃癌におけるインテグリンの分布とその意義

取得学位 : 博士（医学）, 学位授与番号 : 医博乙第1236号,学位授与年月日：平成5年7月7日,学位授与年：199

Reduced dose of PTCy followed by adjuvant alpha-galactosylceramide enhances GVL effect without sacrificing GVHD suppression

Posttransplantation cyclophosphamide (PTCy) has become a popular option for haploidentical hematopoietic stem cell transplantation (HSCT). However, personalized methods to adjust immune intensity after PTCy for each patient's condition have not been well studied. Here, we investigated the effects of reducing the dose of PTCy followed by alpha -galactosylceramide (alpha -GC), a ligand of iNKT cells, on the reciprocal balance between graft-versus-host disease (GVHD) and the graft-versus-leukemia (GVL) effect. In a murine haploidentical HSCT model, insufficient GVHD prevention after reduced-dose PTCy was efficiently compensated for by multiple administrations of alpha -GC. The ligand treatment maintained the enhanced GVL effect after reduced-dose PTCy. Phenotypic analyses revealed that donor-derived B cells presented the ligand and induced preferential skewing to the NKT2 phenotype rather than the NKT1 phenotype, which was followed by the early recovery of all T cell subsets, especially CD4(+)Foxp3(+) regulatory T cells. These studies indicate that alpha -GC administration soon after reduced-dose PTCy restores GVHD-preventing activity and maintains the GVL effect, which is enhanced by reducing the dose of PTCy. Our results provide important information for the development of a novel strategy to optimize PTCy-based transplantation, particularly in patients with a potential relapse risk

A New Serum Biomarker Set to Detect Mild Cognitive Impairment and Alzheimer’s Disease by Peptidome Technology

Background: Because dementia is an emerging problem in the world, biochemical markers of cerebrospinal fluid (CSF) and radio-isotopic analyses are helpful for diagnosing Alzheimer’s disease (AD). Although blood sample is more feasible and plausible than CSF or radiological biomarkers for screening potential AD, measurements of serum amyloid- β (Aβ), plasma tau, and serum antibodies for Aβ1 - 42 are not yet well established. Objective: We aimed to identify a new serum biomarker to detect mild cognitive impairment (MCI) and AD in comparison to cognitively healthy control by a new peptidome technology. Methods: With only 1.5μl of serum, we examined a new target plate “BLOTCHIP®” plus a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) to discriminate control (n = 100), MCI (n = 60), and AD (n = 99). In some subjects, cognitive Mini-Mental State Examination (MMSE) were compared to positron emission tomography (PET) with Pittsburgh compound B (PiB) and the serum probability of dementia (SPD). The mother proteins of candidate serum peptides were examined in autopsied AD brains. Results: Apart from Aβ or tau, the present study discovered a new diagnostic 4-peptides-set biomarker for discriminating control, MCI, and AD with 87% of sensitivity and 65% of specificity between control and AD (***p  Conclusion: The present serum biomarker set provides a new, rapid, non-invasive, highly quantitative and low-cost clinical application for dementia screening, and also suggests an alternative pathomechanism of AD for neuroinflammation and neurovascular unit damage

Gliding Motility of Babesia bovis Merozoites Visualized by Time-Lapse Video Microscopy

BACKGROUND: Babesia bovis is an apicomplexan intraerythrocytic protozoan parasite that induces babesiosis in cattle after transmission by ticks. During specific stages of the apicomplexan parasite lifecycle, such as the sporozoites of Plasmodium falciparum and tachyzoites of Toxoplasma gondii, host cells are targeted for invasion using a unique, active process termed "gliding motility". However, it is not thoroughly understood how the merozoites of B. bovis target and invade host red blood cells (RBCs), and gliding motility has so far not been observed in the parasite. METHODOLOGY/PRINCIPAL FINDINGS: Gliding motility of B. bovis merozoites was revealed by time-lapse video microscopy. The recorded images revealed that the process included egress of the merozoites from the infected RBC, gliding motility, and subsequent invasion into new RBCs. The gliding motility of B. bovis merozoites was similar to the helical gliding of Toxoplasma tachyzoites. The trails left by the merozoites were detected by indirect immunofluorescence assay using antiserum against B. bovis merozoite surface antigen 1. Inhibition of gliding motility by actin filament polymerization or depolymerization indicated that the gliding motility was driven by actomyosin dependent process. In addition, we revealed the timing of breakdown of the parasitophorous vacuole. Time-lapse image analysis of membrane-stained bovine RBCs showed formation and breakdown of the parasitophorous vacuole within ten minutes of invasion. CONCLUSIONS/SIGNIFICANCE: This is the first report of the gliding motility of B. bovis. Since merozoites of Plasmodium parasites do not glide on a substrate, the gliding motility of B. bovis merozoites is a notable finding

Successful rechallenge with cetuximab after progression with nivolumab for recurrent cervical lymph node metastasis from carcinoma of the tongue.

We can infer that the immunostimulatory effect of nivolumab and reactivation of cetuximab enhance the antitumor effect of the therapy

Comparison of the wound-healing efficacy of gelatin sponge dressings and that of artificial dermis using atelocollagen in a rat cranial periosteal defect model.

In oral surgery, tissue loss may occur in some cases, resulting in bone exposure and subsequent wound infection and possible scar formation during secondary healing. In this study, Terudermis® Artificial Dermis (AD-T), a dermal defect graft made from processed bovine dermis collagen and gelatin sponge (GS) were used as dressings on 100-mm2 wounds with exposed bone on the heads of rats. For the control group, the wound was left exposed. The wound-healing efficacy of the treatment was compared macroscopically and histologically among the three groups at 1, 2, and 4 weeks after surgery. Complete wound healing was achieved faster in the AD-T group than in the GS group, and osteoblasts appeared on the bone surface, indicating accelerated bone remodeling. Furthermore, in the AD-T group, there was an increased production of newly formed blood vessels, fibroblasts and osteoblasts positive for anti-cortactin antibodies, which are believed to contribute to wound healing. Our findings suggest that AD-T is better than GS as a wound dressing material.滋賀医科大学令和3年