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Yoshiyasu Umeda Hiroaki Hayashi Seiko Sugiyama Yumi Aoyama 《The Journal of dermatology》2020,47(11):1322-1325
Programmed death 1 (PD-1) inhibitors are increasingly used for the treatment of malignancies. Despite the clinical benefits, unpredictable and potentially fatal side-effects may occur. We report a psoriatic patient who developed systemic capillary leak syndrome (SCLS) after starting a PD-1 checkpoint inhibitor. In order to determine which factors could trigger the development of SCLS in a patient with stable psoriasis after starting anti-PD-1 therapy, serum cytokines were serially measured before and after the development of SCLS in this patient. We also retrospectively reviewed 28 previously reported patients presenting clinical exacerbations of pre-existing psoriasis or the de novo induction of psoriasis after anti-PD-1 therapy. In 16 of the 28 patients (57.1%), the interval between last anti-PD-1 therapy and exacerbations of pre-existing psoriasis or the de novo induction of psoriasis was less than 28 days. The timing of the onset of SCLS in this patient was coincident with the increase in lymphocyte counts and at 22 days after last anti-PD-1 therapy. In 75%, however, anti-PD-1 therapy was able to be restarted and was tolerated well. Increased levels of interleukin (IL)-2, IL-6, interferon-γ and tumor necrosis factor-α, in addition to a persistent increase in vascular endothelial growth factor (VEGF), were detected at onset of SCLS. An increase in pro-inflammatory cytokines and VEGF, when combined with a rapid and sequential recovery of neutrophils and lymphocytes after anti-PD-1 therapy, would predict the development of SCLS. Clinicians need to be aware that patients with psoriasis are at risk of a potentially fatal disease, SCLS, when anti-PD-1 therapy is started. 相似文献
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目的 探讨血管内皮生长因子(vascular endothelial growth factor,VEGF)基因修饰诱导多能干细胞(induced pluripotent stem cells,iPS)的生物学特性。方法 将培养好的iPS细胞分为3组,即N0(纯iPS培养)组、N1(空腺病毒载体转染iPS)组、N2(转染VEGF基因的iPS)组; 3组细胞分别进行传代培养,并采用MTT方法检测转染VEGF基因对细胞增殖的影响; 采用酶联免疫(ELISA)方法检测细胞培养上清液中VEGF的表达水平。结果 转染VEGF基因对iPS细胞增殖没有明显影响; N2组iPS细胞分泌的VEGF蛋白表达水平较N1组显著增加(P<0.05)。结论 经VEGF基因转染的iPS可正常存活生长,并可稳定表达该基因。 相似文献
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目的 探讨枸杞多糖(LBP)对颅内动脉瘤(IA)大鼠核蛋白因子-κB(NF-κB)蛋白通路及血管内皮组织炎性损伤的影响。方法 取SD雌性大鼠50只,采用切除双侧卵巢并结扎左侧颈总动脉及双侧肾动脉后支以构建IA模型,随机分为IA模型组、LBP低(5 mg/kg)、中(10 mg/kg)、高(20 mg/kg)剂量组,另取10只大鼠,只暴露卵巢、颈总动脉、双侧肾动脉后支,不进行摘除和结扎,作为对照组(Control组); 各组均于手术1周后,开始给药,Control组、IA模型组经灌胃给予生理盐水,LBP各剂量组灌胃给予相应剂量药物,1次/d,共给药30 d; 末次给药12 h后处死,取大鼠血液用酶联免疫吸附法(ELISA)检测血清炎性因子白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)及血管内皮损伤标志物血管内皮生长因子(VEGF)、血管内皮素(ET)水平; 分离取出大鼠脑动脉(Wills)环,在40倍显微镜下检查大脑动脉(Wills)环病理改变,并检测动脉瘤血管壁厚度及动脉瘤体积; 取脑动脉瘤血管组织,用苏木精-伊红染色(HE)检测动脉瘤血管组织病理变化; 蛋白免疫印迹法(Western blot)检测动脉瘤血管组织NF-κB,Toll样受体-4(TLR4)蛋白表达水平。结果 与Control组比较,IA模型组大鼠Willis环上凸起、管壁厚度和肿动脉瘤体积、动脉瘤内皮细胞空泡变性及炎性细胞浸润等病理损伤程度、血清IL-6,TNF-α,VEGF,ET水平、动脉瘤血管组织NF-κB和TLR4蛋白表达水平明显升高(P<0.05); 与IA模型组比较,LBP低、中、高剂量组大鼠Willis环上凸起、管壁厚度和动脉瘤体积、动脉瘤内皮细胞空泡变性及炎性细胞浸润等病理损伤程度、血清IL-6,TNF-α,VEGF,ET水平、动脉瘤血管组织NF-κB和TLR4蛋白表达水平明显降低(P<0.05),且LBP各剂量组上述指标水平呈剂量依赖性降低。结论 LBP可能通过抑制TLR4/NF-κB通路激活、降低炎症反应来减轻IA血管内皮组织损伤。 相似文献
86.
Hee-young Choi Su-bong Name Ji-eun Lee Ik-soo Byon Je-hyun Seo 《Orbit (Amsterdam, Netherlands)》2016,35(1):6-10
Purpose: To investigate the presence of the Vascular Endothelial Growth Factor (VEGF) and its receptor (VEGFR) in human orbital preadipocytes, and to evaluate the effect of VEGF on human orbital preadipocyte differentiation and adipogenesis in vitro.Results: Four isoforms of VEGF (VEGF121, 155, 189, and 206), VEGFR-1, VEGF-2, and neuropilin-1 were expressed in human orbital preadipocytes. Treatment with 100 ng/ml VEGF induced higher expressions of C/EBPα and LPL than the non-treated control (p = 0.03 and p = 0.01) or treatment with 50ng/ml (p = 0.04 for both). At both concentrations VEGF enhanced the accumulation of intra-cytoplasmic lipid versus the control, and treatment with 100 ng/ml VEGF induced more lipid accumulation than treatment with 50 ng/ml VEGF (p = 0.03).Conclusions: VEGF and VEGFR were observed in human orbital preadipocytes, and exogenous VEGF enhanced adipogenesis in these cells. These results suggest that VEGF plays a role as an autocrine or paracrine growth factor during human orbital preadipocyte differentiation. 相似文献
87.
Yasuaki Ogura Kensuke Fukuchi Hiroki Morimoto Tsurumi Yuki Masaki Otsuka Takatoshi Shimauchi Tetsuya Honda Yoshiki Tokura 《The Journal of dermatology》2022,49(1):124-132
Mamushi bites cause swelling and pain that extend from the bitten site. The coagulopathic, anti-coagulopathic, and vasculopathic actions of mamushi venom result in various laboratory abnormalities, occasionally with muscular, renal, and other organ damage. We investigated the serum biomarkers that were associated with the pathogenesis of mamushi bites, focusing on markers related to tissue-damage and neutrophil activation. Twenty patients (one case of grade 2, 13 cases of grade 3, and six cases of grade 4 of severity) seen by us in one summer season were enrolled. Peripheral blood samples were taken from the patients on day 0, day 2, and day 7 after mamushi bites. In addition to routine blood examination, serum samples were subjected to enzyme-linked immunosorbent assay for citrullinated histone H3 (CitH3), interleukin (IL)-8, IL-17A, IL-22, vascular endothelial growth factor (VEGF), high mobility group box protein 1 (HMGB1), tumor necrosis factor (TNF)-α, and IL-33. Creatinine kinase (CK) values significantly correlated with prothrombin time (PT) levels, suggesting that muscular damage is associated with exaggerated coagulation and fibrinolysis. In the vast majority of patients, HMGB1, TNF-α, and IL-33 were under detection levels. Neutrophil counts did not correlate with PT or CK, indicating that the coagulation disorder and muscular damage were virtually independent of the neutrophil activation. The neutrophil number significantly correlated with CitH3, a representative marker of neutrophil extracellular traps. Moreover, there were significant correlations between neutrophil number, CitH3, IL-8, IL-22, and VEGF. Our study suggests that there are two major cascades in mamushi bites. One is an already characterized venom effect on coagulation, vessels, and muscles. In the other novel cascade, we propose that neutrophil activation with IL-8 leads to the production of IL-22 and VEGF. This sequential event may contribute to both vascular damage and repair. 相似文献
88.
Melatonin reduces oxidative stress and improves vascular function in pulmonary hypertensive newborn sheep 下载免费PDF全文
Flavio Torres Alejandro González‐Candia Camilo Montt Germán Ebensperger Magdalena Chubretovic María Serón‐Ferré Roberto V. Reyes Aníbal J. Llanos Emilio A. Herrera 《Journal of pineal research》2015,58(3):362-373
Pulmonary hypertension of the newborn (PHN) constitutes a critical condition with severe cardiovascular and neurological consequences. One of its main causes is hypoxia during gestation, and thus, it is a public health concern in populations living above 2500 m. Although some mechanisms are recognized, the pathophysiological facts that lead to PHN are not fully understood, which explains the lack of an effective treatment. Oxidative stress is one of the proposed mechanisms inducing pulmonary vascular dysfunction and PHN. Therefore, we assessed whether melatonin, a potent antioxidant, improves pulmonary vascular function. Twelve newborn sheep were gestated, born, and raised at 3600 meters. At 3 days old, lambs were catheterized and daily cardiovascular measurements were recorded. Lambs were divided into two groups, one received daily vehicle as control and another received daily melatonin (1 mg/kg/d), for 8 days. At 11 days old, lung tissue and small pulmonary arteries (SPA) were collected. Melatonin decreased pulmonary pressure and resistance for the first 3 days of treatment. Further, melatonin significantly improved the vasodilator function of SPA, enhancing the endothelial‐ and muscular‐dependent pathways. This was associated with an enhanced nitric oxide‐dependent and nitric oxide independent vasodilator components and with increased nitric oxide bioavailability in lung tissue. Further, melatonin reduced the pulmonary oxidative stress markers and increased enzymatic and nonenzymatic antioxidant capacity. Finally, these effects were associated with an increase of lumen diameter and a mild decrease in the wall of the pulmonary arteries. These outcomes support the use of melatonin as an adjuvant in the treatment for PHN. 相似文献
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