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Po-Fu Chen Chien-Liang Liu Wei-Kuan Lin Kuan-Chieh Chen Pi-Tai Chou Shi-Wei Chu 《Biomedical optics express》2015,6(8):3066-3073
Insulin–gold nanoclusters exhibit outstanding biocompatibility, photostability, and fluorescence quantum efficiency. However, they have never been used in superresolution microscopy, which requires nonlinear switching or saturation of fluorescence. Here we examine the fluorescence and stimulated emission depletion properties of gold nanoclusters. Their bleaching rate is very slow, demonstrating superior photostability. Surprisingly, however, the best depletion efficiency is less than 70%, whereas the depletion intensity requirement is much higher than the expectation from a simple two-level model. Fluorescence lifetime measurement revealed two distinct lifetime components, which indicate intersystem and reverse intersystem crossing during excitation. Based on population dynamic calculation, excellent agreement of the maximal depletion efficiency is found. Our work not only features the first examination of STED with metallic clusters, but also reveals the significance of molecular transition dynamics when considering a STED labeling.OCIS codes: (180.1790) Confocal microscopy, (160.2540) Fluorescent and luminescent materials, (250.6715) Switching, (160.4236) Nanomaterials, (160.1435) Biomaterials 相似文献
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A case of endocapillary proliferative glomerulonephritis with macrophages phagocytosing monoclonal immunoglobulin lambda light chain 下载免费PDF全文
Hirofumi Watanabe Yutaka Osawa Shin Goto Masato Habuka Naofumi Imai Yumi Ito Takayuki Hirose Takaaki Chou Ryuji Ohashi Akira Shimizu Takashi Ehara Takashi Shimotori Ichiei Narita 《Pathology international》2015,65(1):38-42
Multiple myeloma (MM) is a plasma‐cell neoplasm that can cause renal disorders. Renal lesions in MM can present with a very rare pathological manifestation involving a specific monoclonal immunoglobulin (Ig). We report the case of a 33‐year‐old woman who had edema, fatigue, elevated serum creatinine levels, hypoalbuminemia, and hypercholesterolemia. She had persistent hematuria and proteinuria lasting 3 years. Serum protein electrophoresis showed an M‐spike, and serum immunofixation demonstrated the presence of monoclonal IgG λ. She had proteinuria in the nephrotic range, and a monoclonal λ fragment was present on urine immunofixation. Renal biopsy showed proliferative glomerulonephritis with λ light chain and C3c deposition and inflammatory cell infiltration with CD68. Macrophage lysosomes contained λ light chains, suggesting their partial phagocytosis. She was diagnosed with symptomatic MM and was treated with bortezomib and dexamethasone and an autologous peripheral stem cell transplant conditioned with intravenous melphalan. She achieved a partial response with decreased serum monoclonal protein and improved renal function. This case may be categorized as a monoclonal gammopathy‐associated proliferative glomerulonephritis. The biopsy finding of partially phagocytosed Ig λ light chains by macrophages is very rare; this pathological condition is similar to crystal‐storing histiocytosis. 相似文献
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Hu ML Rayner CK Wu KL Chuah SK Tai WC Chou YP Chiu YC Chiu KW Hu TH 《World journal of gastroenterology : WJG》2011,17(1):105-110
AIM:To evaluate the effects of ginger on gastric motility and emptying,abdominal symptoms,and hormones that influence motility in dyspepsia.METHODS:Eleven patients with functional dyspepsia were studied twice in a randomized double-blind manner.After an 8-h fast,the patients ingested three capsules that contained ginger(total 1.2 g) or placebo,followed after 1 h by 500 mL low-nutrient soup.Antral area,fundus area and diameter,and the frequency of antral contractions were measured using ultrasound at frequen... 相似文献
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Ming-Hui Lee Wan-Pei Su Wan-Jen Wang Sing-Ru Lin Chen-Yu Lu Yu-An Chen Jean-Yun Chang Shenq-Shyang Huang Pei-Yi Chou Siou-Ru Ye Szu-Jung Chen Huan He Ting-Hsiu Liu Ying-Tsen Chou Li-Jin Hsu Feng-Jie Lai Shean-Jen Chen Hoong-Chien Lee David Kakhniashvili Steven R. Goodman Nan-Shan Chang 《Oncotarget》2015,6(6):3737-3751
Zfra is a 31-amino-acid zinc finger-like protein, which participates in the tumor necrosis factor signaling. Here, we determined that when nude mice and BALB/c mice were pre-injected with nanogram levels of a synthetic Zfra1–31 or truncated Zfra4–10 peptide via tail veins, these mice became resistant to the growth, metastasis and stemness of melanoma cells, and many malignant cancer cells. The synthetic peptides underwent self-polymerization in phosphate-buffered saline. Alteration of the Ser8 phosphorylation site to Gly8 abolished Zfra aggregation and its-mediated cancer suppression in vivo. Injected Zfra peptide autofluoresced due to polymerization and was trapped mainly in the spleen. Transfer of Zfra-stimulated spleen cells to naïve mice conferred resistance to cancer growth. Zfra-binding cells, designated Hyal-2+ CD3− CD19− Z cells, are approximately 25–30% in the normal spleen, but are significantly downregulated (near 0–3%) in tumor-growing mice. Zfra prevented the loss of Z cells caused by tumors. In vitro stimulation or education of naïve spleen cells with Zfra allowed generation of activated Z cells to confer a memory anticancer response in naïve or cancer-growing mice. In particular, Z cells are abundant in nude and NOD-SCID mice, and can be readily activated by Zfra to mount against cancer growth. 相似文献
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HLA-B27 and its subtypes in 4 Taiwanese Aborigine tribes: a comparison to Han Chinese patients with ankylosing spondylitis 总被引:7,自引:0,他引:7
OBJECTIVE: We surveyed B27 and its subtypes in 5 ethnic groups in Taiwan. METHODS: Blood was obtained from 281 Aborigine people of the Atayal tribe (I-Lan), 141 Paiwan (Ping-Ton), 38 Rukai (Ping-Ton), and 40 Yami (Orchid Island), and also 47 B27+ healthy Han Chinese subjects and 82 B27+ Han patients with ankylosing spondylitis (AS). HLA-B27 and its subtypes were determined by standard methods. RESULTS: A much higher prevalence of B27 was found among the Atayal Aborigines (9.2%), which was significantly different from a lower prevalence in the Paiwan (2.1%; p = 0.004) and even higher than that of Han Chinese (5.59%; p = 0.04). No blood sample from the 38 Rukai Aborigines showed any B27. B2704 was the only subtype (100%) found in the 28 healthy Aborigines and 2 Aborigine patients with AS. However, in Chinese subjects, 40 of 47 (85%) B27+ healthy subjects were B2704, and 7 of 47 (15%) were B2705. In Chinese B27+ AS patients, 77 of 82 (94%) were B2704 and 5 of 82 (6%) were B2705. No other subtypes were found. Only the Aborigines without AS carrying B2704 showed a significant difference from the Chinese without AS carrying B2704 (p = 0.041). CONCLUSION: The different prevalence of B27, but similar frequency of the B2704 subtype, between Aborigines and Han Chinese suggests Aborigines are a unique population and may originate from an Asian country, possibly mainland China. 相似文献
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