Publications by authors named "Yoshiro Kobayashi"

Neutrophils are short-lived and terminally differentiated cells, and therefore, have been considered as effector cells to phagocytose pathogens and kill them or damage tissues [...

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Aging promotes polarization of M2-like macrophages to M1-like macrophages and reduces their phagocytic ability. However, the molecular mechanisms underlying these aging-related changes remain poorly understood. Here, we demonstrate that p53 regulates phagocytic activity in macrophages from young mice but not in those from old ones.

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Whole body irradiation causes significant apoptosis in various tissues such as the thymus. If apoptotic cells outnumber the phagocytic capacity of macrophages, apoptosis becomes secondary necrosis, inducing inflammatory cytokine expression in macrophages. Radiation also induces thymic lymphomas in C57BL/6 mice after four consecutive irradiations with 1.

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Exposure to an enriched environment (EE) affects not only brain functions but also immune responses upon viral or bacterial infections. In this study, we examined changes in the phagocytic response and chemokine production of resident peritoneal macrophages after mice had been housed under EE conditions for 6 or 8 weeks, and then explored the possibility that EE could cause a change in the macrophage phenotype by means of flow cytometry as well as quantitative RT-PCR. The percentages of EE macrophages phagocytosing S.

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Article Synopsis
  • Aortobronchial fistula (ABF) is a rare and dangerous complication that can occur after thoracic aortic replacement surgery, often leading to life-threatening issues like respiratory failure.
  • A 48-year-old male patient with a recent aortic surgery experienced massive hemoptysis and severe breathing difficulties, and was diagnosed with ABF after imaging showed blood leakage from the aortic graft.
  • The treatment involved emergency thoracic endovascular aortic repair (TEVAR) combined with venovenous extracorporeal membrane oxygenation (VV ECMO), which successfully managed his condition and improved his respiratory status.
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Cellular senescence is classified into two groups: replicative and premature senescence. Gene expression and epigenetic changes are reported to differ between these two groups and cell types. Normal human diploid fibroblast TIG-3 cells have often been used in cellular senescence research; however, their epigenetic profiles are still not fully understood.

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Objective: The aim of this study was to reveal the mechanism of improved arterial oxygenation by measuring the changes in oxygenation before and after initiation of left heart bypass (LHB) during one-lung ventilation (OLV) for thoracic aortic surgery.

Design: Prospective, observational study.

Setting: Single-institution, private hospital.

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We report a case of hyperthyroidism diagnosed from refractory tachycardia and hypotension during surgery. Although the patient had exhibited tachycardia preop- eratively, it was difficult to suspect hyperthyroidism due to specific conditions of neurosurgical patient Eventually diagnosis of hyperthyroidism was made by exclusion, and prompt treatment was effectively initiated. Recently several reports suggested that landiolol was effective for rate control in patients with hyperthyroidism.

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A 53-year-old man with chronic renal tubular acidosis and subclinical hypothyroidism underwent lower leg amputation surgery under general anesthesia. Perioperative acid-base management in such patients poses many difficulties because both pathophysiologies have the potential to complicate the interpretation of capnometry and arterial blood gas analysis data; inappropriate correction of chronic metabolic acidosis may lead to postoperative respiratory deterioration. We discuss the management of perioperative acidosis in order to achieve successful weaning from mechanical ventilation and promise a complete recovery from anesthesia.

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Secondary necrotic cells, which are generated if apoptotic cells are incompletely cleared, induce severe inflammatory responses involving MIP-2 production and subsequent neutrophil infiltration. Recently, we showed that the phagocytic capacity of peritoneal resident macrophages from wild type (WT) aged mice as well as SMP30(-/-) mice fed a VC-limited diet as to secondary necrotic cells was reduced as compared with that in young mice, and that the inflammatory responses induced were stronger than those in young mice, presumably because of the delay in removal of secondary necrotic cells in aged mice. In this study, we investigated why MIP-2 production was increased in aged mice upon injection of secondary necrotic cells and why the phagocytic capacity of peritoneal resident macrophages from aged mice was reduced.

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If apoptotic cells are not removed efficiently, they may proceed to the stage of secondary necrosis, which would cause inflammation. Therefore, identification of cause(s) and agent(s) for down-modulating phagocytosis of apoptotic cells would help understand the pathologies. In this study we found that macrophage-mediated phagocytosis of apoptotic cells was suppressed by both soluble and particulate β-glucan.

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Neutrophil extracellular traps (NETs) are involved in bacterial killing as well as autoimmunity, because NETs contain proteases, bactericidal peptides, DNA and ribonucleoprotein. NETs are formed via a novel type of cell death called NETosis. NETosis is distinct from apoptosis, but it resembles necrosis in that both membranes are not intact so that they allow intracellular proteins to leak outside of the cells.

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Aim: Secondary necrotic cells generated in vivo induce inflammatory responses; for example, the production of macrophage inflammatory protein-2 (MIP-2) and subsequent infiltration of neutrophils. The aim of the present study was to elucidate the effect of aging on the phagocytosis of secondary necrotic cells and the inflammatory responses by using either wild-type (WT) young mice, WT aged mice or senescence-accelerated mice (SMP30(-/-) mice).

Methods: The phagocytosis of secondary necrotic neutrophils with resident macrophage from either WT young mice, WT aged mice or SMP30(-/-) mice was examined by coculturing macrophages with secondary necrotic neutrophils in vitro.

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Paraplegia is a serious complication after thoracoabdominal aortic aneurysm repair. Therefore, maintenance of spinal cord perfusion pressure, drainage of cerebrospinal fluid, and avoidance of opioids are important for prevention of paraplegia Management of acute post-thoracotomy pain is necessary not only to keep the patient comfortable but also to minimize postoperative complications. However, epidural analgesia, a common method of pain control, is hard to use because of existing postoperative coagulopathy and avoidance of spinal cord ischemia Although both paravertebral block and epidural analgesia provide comparable pain relief after thoracic surgery, paravertebral block has lesser detrimental effects on spinal cord perfusion and better preserves the possibility to monitor neurologic function than epidural analgesia.

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Study Objective: To examine the change in liver-type fatty acid-binding protein (L-FABP) levels in patients undergoing aortic arch surgery and the correlation between L-FABP and postoperative acute kidney injury.

Design: Prospective observational study.

Setting: Operating room of a general hospital.

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Massive wasp envenomation can cause not only severe immediate allergic reactions and anaphylaxis but also severe delayed toxin-mediated systemic reactions, including hemolysis, coagulopathy, rhabdomyolysis, acute renal failure, and hepatotoxicity. However, reports of the latter type of reactions are rare. The subject of this case report, a 66-year-old man, was stung more than 30 times during an attack by wasps.

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Here we developed a new cell-permeative lucigenin derivative, 10,10'-dimethyl-9,9'-biacridinium bis(monomethyl terephthalate) (MMT), to detect intracellular superoxide production. Both MMT and lucigenin were specific to superoxide among reactive oxygen species tested. Although lucigenin barely penetrated into cells, MMT accumulated in mitochondria in a variety of cells such as neutrophils.

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Article Synopsis
  • Regular exercise is associated with health benefits, including lower protein and DNA oxidation levels, although active individuals showed higher urinary 8-OHdG levels compared to sedentary ones.
  • Active subjects had greater neutrophil density and function, indicating enhanced immune response, resembling effects typically seen with acute exercise.
  • The findings suggest that active individuals have higher IgM antibodies against 4-hydroxy-2-nonenal adducts, pointing to possible protective health benefits linked to oxidative stress and exercise.
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Neutrophils are excreted into the vaginal vault at metestrus during the estrous cycle, and this phenomenon has long been used to determine the phase of the estrous cycle. A much smaller number of neutrophils are also detected in the uterus and the ovary. Recently, we provided several lines of evidence supporting the notion that neutrophils infiltrate into the ovary to regulate the estrous cycle by opioid peptides.

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Throughout life, one's blood supply depends on sustained division of hematopoietic stem cells (HSCs) for self-renewal and differentiation. Within the bone marrow microenvironment, an adhesion-dependent or -independent niche system regulates HSC function. Here we show that a novel adhesion-dependent mechanism via integrin-β3 signaling contributes to HSC maintenance.

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Annexin A1 (ANXA1) is a well-known anti-inflammatory protein that is expressed on the surface of apoptotic cells. Annexin A4 (ANXA4) is also recruited from the nucleus to the cytoplasm in apoptotic cells, although it is not known whether or not ANXA4 is expressed on the surface of apoptotic cells. In this study, we obtained rabbit anti-human ANXA1 and ANXA4 antibodies, and then examined whether or not ANXA1 and ANXA4 are expressed on the surface of early and late human apoptotic cells.

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