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21.
Clinical and Experimental Nephrology - Some pediatric patients on maintenance dialysis may need end-of-life care in the future because of being excluded from the indication of kidney...  相似文献   
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Nanofiber vascular grafts have been shown to create neovessels made of autologous tissue, by in vivo scaffold biodegradation over time. However, many studies on graft materials and biodegradation have been conducted in vitro or in small animal models, instead of large animal models, which demonstrate different degradation profiles. In this study, we compared the degradation profiles of nanofiber vascular grafts in a rat model and a sheep model, while controlling for the type of graft material, the duration of implantation, fabrication method, type of circulation (arterial/venous), and type of surgery (interposition graft). We found that there was significantly less remaining scaffold (i.e., faster degradation) in nanofiber vascular grafts implanted in the sheep model compared with the rat model, in both the arterial and the venous circulations, at 6 months postimplantation. In addition, there was more extracellular matrix deposition, more elastin formation, more mature collagen, and no calcification in the sheep model compared with the rat model. In conclusion, studies comparing degradation of vascular grafts in large and small animal models remain limited. For clinical translation of nanofiber vascular grafts, it is important to understand these differences.  相似文献   
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Objective This study assessed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses to the BNT162b2 mRNA vaccine in Japanese healthcare workers. Methods In this prospective cohort study, participants received two doses of the BNT162b2 mRNA vaccine on days 0 and 21 and provided blood for anti-SARS-CoV-2 antibody testing before the first vaccine and on days 21 and 35 after vaccination. Anti-spike protein immunoglobulin G (S-IgG) was measured using Abbott and Fujirebio chemiluminescent immunoassays. Patients One hundred healthcare workers (median age: 39 years old, interquartile range: 30-48 years old), including 6 who had been previously infected with SARS-CoV-2 and 3 individuals taking immunosuppressive drugs, participated in the study. Results The S-IgG antibody titers (AU/mL) measured using both the Abbott and Fujirebio assays increased significantly (p<0.001) over time, both with a prevalence of 100% at 35 days after the first vaccination. The multivariate log-normal linear regression analysis indicated the effect of immunosuppressant medication using both the Abbott (p=0.013) and Fujirebio (p=0.039) assays on S-IgG levels after complete vaccination. Pearson''s correlation coefficient between the Abbott and Fujirebio S-IgG results in all 300 samples collected before and after vaccination and 50 positive controls from patients with coronavirus disease 2019 were 0.963 [95% confidence interval (CI): 0.954-0.970, p<0.001] and 0.909 (95% CI: 0.845-0.948, p<0.001), respectively. Conclusion The BNT162b2 mRNA vaccine was effective at increasing S-IgG levels in Japanese immunocompetent healthcare workers. The Fujirebio S-IgG assay showed high diagnostic accuracy, using the Abbott S-IgG assay as the reference test.  相似文献   
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1. RD3-0028, a benzodithiin compound, has potent antiviral activity against respiratory syncytial virus (RSV) in cell culture. The compound also inhibits growth of RSV and improves pathologic changes of interstitial pneumonia in the immunosuppressed mouse when delivered by small-particle aerosol. 2. In the present study, the absorption, distribution and excretion of 14C-RD3-0028 were compared in rat following either a single aerosol treatment or oral administration. 3. The plasma concentration was maintained at the same level from 5 min to 1 h, and decreased with a half-life of 2.2 +/- 0.1 h for 1-8 h. 4. The excretion of radioactivity in the urine and faeces at 24 h after aerosol treatment was 89.3 and 4.5%, respectively, indicating that almost all the radioactivity was rapidly excreted in the urine. The excretion of total radioactivity was 98.9% within 168 h. 5. The concentrations of radioactivity in the lung and trachea following aerosol treatment were higher than those in other tissues, and were detected even at 72 h. 6. These results suggest that the aerosol treatment might be useful for delivering RD3-0028 to the respiratory tract of RSV-infected patients.  相似文献   
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An investigation has been made with regard to the clinical picture of 87 terminally ill patients with lung cancer. It has yielded the following points. 1) Seven patients had been informed of their diagnosis. 2) Intravenous hyperalimentation was administered in 78 cases (90%), oxygen therapy in 68 cases (78%), and morphine in 35 cases (40%). 3) The most frequent cause of death in these patients was respiratory failure, due to progress of cancer, then infection, pleural, or pericardial effusion, or interstitial pneumonitis. 4) Psychic disturbances involved anxiety over breathing, depression, and delirium. In only 12% of the patients did the mental condition seem normal until death. 5) To deal with the dying patient's needs, it is necessary to establish proper treatment for the control of sensory dyspnea and for psychosocial support by a psychiatrist and other professionals for members of the family.  相似文献   
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The water soluble material (LEM) was prepared from the solid culture medium in which Lentinus edodes mycelia were growing actively. An alcohol insoluble material was prepared from LEM and subjected to Sepharose 6B gel filtration. The void fraction (LAP1) was composed mainly of xylose-rich heteroglycan and protein. From LAP1, a heteroglycan fraction (LAF1) was prepared by DEAE-Sepharose CL-6B column chromatography. LAP1 and LAF1 enhanced the incorporation of [3H]thymidine into mouse splenic cells (SPs). At each of the optimum doses, the rate of the incorporation was about 10 times as high with LAF1 as with LAP1. Such mitogenic responses were not induced in nylon-column effluent SPs and thymocytes. sIg-expressed cells were responsive to LAF1, but not to LAP1. Moreover, with each fraction, the incorporation was enhanced more in plastic adherent splenic cells (ADs) than in SPs. The flow cytometric assay revealed that the number of Mac-1+ cells is about 13 times as many in ADs as in SPs and that the number of Ly-5+ or Thy-1.2+ cells is considerably reduced in ADs compared with that in SPs. Thus, the present studies suggest that LAP1 and LAF1 act as mitogens predominantly for mouse splenic macrophages and/or monocytes.  相似文献   
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Role of TGF-beta2 in the human hair cycle   总被引:9,自引:0,他引:9  
Male pattern baldness is the result of premature entry into catagen due to androgens. In order to prevent hair loss, it is important to understand two critical steps, i.e., the induction mechanism of premature entry and the regression process of catagen. At the initiation, dihydrotestosterone (DHT) stimulates synthesis of transforming growth factor-beta2 (TGF-beta2) in dermal papilla cells. TGF-beta2 suppresses proliferation of epithelial cells and stimulates synthesis of certain caspases. Then TGF-beta2 triggers the intrinsic caspase network and subsequently epithelial cells are eliminated through apoptotic cell death. TGF-beta antagonists are effective in preventing catagen-like morphological changes and in promoting elongation of hair follicles in vivo and in vitro. These lines of evidence strongly suggest the presence of a "catagen cascade" in male pattern baldness, involving: (1) the conversion of testosterone to DHT by type II 5-alpha-reductase; (2) the synthesis of TGF-beta2 in dermal papilla cells; and (3) the activation of the intrinsic caspase network. These sequential events contribute to the shortening of the human hair cycle.  相似文献   
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