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91.
Lymphoid‐tissue dendritic cells (DCs) are short‐lived and need to be continuously replenished from bone marrow‐derived DC progenitor cells. Fms‐related tyrosine kinase 3 is expressed during cellular development from hematopoietic progenitors to lymphoid‐tissue DCs. Fms‐related tyrosine kinase 3 ligand (Flt3L) is an essential, nonredundant cytokine for DC progenitor to lymphoid tissue DC differentiation and maintenance. However, which cells contribute to Flt3L production and how Flt3L cytokine levels are regulated in steady state and during immune reactions remains to be determined. Here we demonstrate that besides nonhematopoietic cells, WT T cells produce Flt3L and contribute to the generation of both classical DCs (cDCs) and plasmacytoid DCs in Flt3L?/? mice. Upon stimulation in vitro, CD4+ T cells produce more Flt3L than CD8+ T cells. Moreover, in vivo stimulation of naïve OT‐II CD4+ T cells with OVA leads to increase of pre‐cDCs and cDCs in draining lymph nodes of Flt3L?/? mice in a partially Flt3L‐dependent manner. Thus, Flt3L‐mediated lymphoid tissue DC homeostasis is regulated by steady‐state T cells as well as by proliferative T cells, fostering local development of lymphoid organ resident DCs.  相似文献   
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Radish mosaic virus (RaMV) is a crucifer-infecting comovirus that has been detected worldwide. Here, we report the successful construction of a full-length infectious cDNA clone of RaMV. The full-length cDNA clones corresponding to RNA1 and RNA2 of a Japanese isolate of RaMV were cloned into the pBlueScript plasmid or the binary vector pCAMBIA1301 downstream of the cauliflower mosaic virus 35S promoter. Mechanical inoculation or agroinoculation of Nicotiana benthamiana with these vectors resulted in systemic RaMV infections causing symptoms similar to those caused by the wild-type parental virus. The presence of progeny virus was verified by western blot analysis and electron microscopy.  相似文献   
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Clinical Autonomic Research - Delayed orthostatic hypotension (DOH), a fall in blood pressure after a 3-min cutoff, is clinically meaningful. The aim of this study was to elucidate the clinical and...  相似文献   
95.
The gastrointestinal tract is a rare site for metastatic lung cancer. Programmed cell death-ligand 1 (PD-L1) expression in lung cancer is a biomarker for the response to anti-PD-1/PD-L1 therapy. We investigated clinicopathological features and PD-L1 expression in 25 gastrointestinal metastatic tumors from the lung and primary adenocarcinoma of the small bowel. The small bowel was the most common site (16/25; 64%) of gastrointestinal tract lung cancer metastasis. A total of 19 (76%) of the gastrointestinal metastasis showed PD-L1 expression in ≥5% of tumor cells, with 14 (56%) showing high expression levels (≥50%). In contrast, 21 (84%) expressed PD-L1 in ≥5% immune cells, including 4 (16%) showing a high expression levels (≥50%). The PD-L1 expression on tumor cells and immune cells in primary lung cancer and corresponding gastrointestinal metastasis was concordant in 13 (68%) and 11 (58%) of the 19 paired cases, respectively. Small-bowel metastasis of lung cancer was characterized by a higher incidence of perforation (31% vs. 0%), ulcerated mass (83% vs. 60%), and neoplastic PD-L1 expression (75% vs. 0%) compared to primary small-bowel adenocarcinoma. Gastrointestinal metastasis from lung cancer might be a potential target for immune checkpoint inhibitor therapy, given its high expression of PD-L1.  相似文献   
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Odontology - Oral scanners allow dental impressions to be taken in a short time without the use of an impression material. However, it has been noted that high impression accuracy cannot be...  相似文献   
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ObjectiveWe describe a case of intracranial and extracranial multiple arterial dissecting aneurysms in rheumatoid arthritis (RA).Case PresentationA 29-year-old man with a medical history of RA since 18 years of age was admitted to our hospital for vomiting, dysarthria, and conscious disturbance. At 23, he underwent ligation of the left internal carotid artery (ICA) with superficial temporal artery to middle cerebral artery anastomosis because of acute infarct of the left hemisphere caused by arterial dissection of the left ICA. During the current admission, computed tomography (CT) revealed subarachnoid hemorrhage, and digital subtraction angiography (DSA) demonstrated dissecting aneurysms of the left intracranial vertebral artery (VA) and right extracranial VA. We diagnosed him with a ruptured dissecting aneurysm of the left intracranial VA and performed endovascular parent artery occlusion on the left VA. For the right unruptured VA aneurysm, we performed coil embolization simultaneously. At 2 weeks after the endovascular treatment, follow-up DSA revealed that multiple de novo dissecting aneurysms developed on the origin of the left VA and left and right internal thoracic arteries. Those aneurysms were treated with coil embolization. Other remaining aneurysms on the left thyrocervical trunk, right transverse cervical artery, and both common iliac arteries were treated by conservative therapy. While continuing medical treatment for RA, the patient recovered and was discharged to a rehabilitation hospital.ConclusionConsidering that RA-induced vasculitis can be a potential risk of vascular complications including multiple arterial dissections, physicians should carefully perform endovascular interventional procedures for patients with long-term RA.  相似文献   
100.
IntroductionSome clinicians administer antibiotics in adhesive SBO treatment to prevent bacterial translocation without evidence confirming reduced sepsis and mortality. We aimed to evaluate the effectiveness of preventive antibiotic administration in nonoperative treatment of adhesive small bowel obstruction (SBO) in a retrospective study.MethodsUsing a Japanese national inpatient database, we identified 114,786 eligible patients with adhesive SBO and divided patients into a group who did not receive intravenous antibiotics in the initial 2 consecutive days after admission (control group, n = 71,666) and a group who received intravenous antibiotics ≥2 days after admission (antibiotic group, n = 43,120). To compare the in-hospital mortality, occurrence of sepsis, septic shock, Clostridioides difficile colitis, length of stay, and total costs between the two groups, we performed instrumental variable analyses to adjust for measured and unmeasured confounding factors.ResultsOverall, in-hospital mortality was 2.2%, and the occurrence of sepsis was 0.8%. In the instrumental variable analyses, no significant differences were found for in-hospital mortality, occurrence of sepsis, septic shock, Clostridioides difficile colitis, or total hospitalization costs. The antibiotic group showed a longer length of stay than the control group (coefficient, 1.9 days; 95% confidence interval, 0.6–3.2).ConclusionsIn this large nationwide cohort of patients with adhesive SBO, we found no benefit regarding preventive antibiotic administration in nonoperative treatment; however, antibiotic administration was associated with a longer hospital stay. These results did not support routine administration of antibiotics at admission to prevent bacterial translocation.  相似文献   
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