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Amyloid precursor protein (APP) is a type 1 transmembrane glycoprotein, and its homologs amyloid precursor-like protein 1 (APLP1) and amyloid precursor-like protein 2 (APLP2) are highly conserved in mammals. APP and APLP are known to be intimately involved in the pathogenesis and progression of Alzheimer’s disease and to play important roles in neuronal homeostasis and development and neural transmission. APP and APLP are also expressed in non-neuronal tissues and are overexpressed in cancer cells. Furthermore, research indicates they are involved in several cancers. In this review, we examine the biological characteristics of APP-related family members and their roles in cancer. 相似文献
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Qianqian Liu Yu-Jin Kim Gwang-Bum Im Jintao Zhu Yuzhou Wu Yijing Liu Suk Ho Bhang 《Advanced functional materials》2021,31(12):2008171
Inorganic nanoparticles (NPs) offer significant advantages to the biomedical field owing to their large surface area, controllable structures, diverse surface chemistry, and unique optical and physical properties. Researchers worldwide have shown that inorganic NPs and the released metal ions can act as therapeutic agents in targeted tissues or to cure various diseases without acute toxicity. In this progress report, the recent developments in inorganic NPs with different compositions directly used as therapeutics are discussed. First, the recent convergence of nanotechnology and biotechnology in biomedical applications as well as the unique functions, features, and advantages of inorganic NPs in biomedical applications are summarized. Thereafter, the biological effects of inorganic compositions in NPs which include balancing the intracellular redox environment, regulating the specific cellular signaling and cellular behaviors, and apoptosis are explained. In addition, the emerging therapeutic applications of inorganic NPs in various diseases are exemplified. Finally, the perspectives and challenges for overcoming the weaknesses of inorganic NPs as therapeutics are discussed. By carefully considering and investigating the biological effects of inorganic NPs and metal ions released from NPs, more promising inorganic NPs based therapeutic agents can be developed. 相似文献
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G. Seeta Rama Raju E. Pavitra L. Krishna Bharat Gattupalli Manikya Rao Tae-Joon Jeon Yun Suk Huh Young-Kyu Han 《Ceramics International》2018,44(12):13852-13857
Upconversion Sr2(Gd.98-xEr.02Ybx)8Si6O26 (SGSO:2Er3+/xYb3+) phosphor materials were synthesized using a citrate sol-gel process. X-ray diffraction patterns confirmed their hexagonal structure. Field emission scanning electron microscopy images of SGSO:2Er3+/xYb3+ phosphors depicted submicron particles. The enhanced upconversion luminescence properties of SGSO:2Er3+/xYb3+ phosphors were analysed as a function of Yb3+ ion concentration and laser power. The energy transfer induced enhanced emission of the Er3+/ Yb3+ ions co-doped SGSO phosphors was ascribed to multi-phonon relaxation. The calculated chromaticity coordinates of the SGSO:2Er3+/xYb3+ phosphors showed emissions could be tuned by changing Yb3+ ion concentration. Optimized sample exhibited the chromaticity coordinate values near to the ultra-high definition television standard green emission coordinates. 相似文献
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Nazmul Abedin Khan Biswa Nath Bhadra Suk Woo Park Yong‐Su Han Sung Hwa Jhung 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(12)
Polyanilines (pANIs), loaded with phosphotungstic acid (PTA), are pyrolyzed to get WO3 or W2N (≈6 and ≈7 nm, respectively), which is well‐dispersed on pANI‐derived porous carbons (pDCs). Depending on the pyrolysis temperature, WO3/pDC, W2N/pDC, or W2N‐W/pDCs could be obtained selectively. pANI acts as both the precursor of pDC and the nitrogen source for the nitridation of WO3 into W2N during the pyrolysis. Importantly, W2N could be obtained from the pyrolysis without ammonia feeding. The obtained W2N/pDC is applied as a heterogeneous catalyst for the oxidative desulfurization (ODS) of liquid fuel for the first time, and the results are compared with WO3/pDC and WO3/ZrO2. The W2N/pDC is very efficient in ODS with remarkable performance compared with WO3/pDC or WO3/ZrO2, which is applied as a representative ODS catalyst. For example, W2N/pDC shows around 3.4 and 2.7 times of kinetic constant and turnover frequency (based on 5 min of reaction), respectively, compared to that of WO3/ZrO2. Moreover, the catalysts could be regenerated in a facile way. Therefore, W2N/pDC could be produced facilely from pyrolysis (without ammonia feeding) of PTA/pANI, and W2N, well‐dispersed on pDC, can be suggested as a very efficient oxidation catalyst for the desulfurization of liquid fuel. 相似文献
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