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81.
Jianhua?HouEmail author Zhixiong?Yang Zhiru?Li Haoyu?Chai Ruiqi?ZhaoEmail author 《Journal of molecular modeling》2017,23(8):242
We designed nine endohedral dodecahedrane heterodimers H@C20Hn-C20Hn@M (M = Cu, Ag, and Au, n = 15, 18, and 19) that may act as single-molecule spin switches, and we predicted theoretically that the ground states of the dimmers shift from low-spin states (S = 0) to the high-spin states (S = 1) under an external electric field applied parallel or perpendicular to the molecular symmetry axes, consisting well with the analyses of Stark effect. Molecular orbitals analyses provide an intuitive insight into the spin crossover behavior. This study expands the application of endohedral chemistry and provides new molecules for designing single-molecule spin switch. 相似文献
82.
Two generic, fast, sensitive and novel electrochemical immunosensors have been developed. Initially, a layer of plasma-polymerized Nafion film (PPF) was deposited on the platinum electrode surface, then positively charged tris(2,2'-bipyridyl)cobalt(III) (Co(bpy)(3)(3+)) and negatively charged gold nanoparticles were assembled on the PPF-modified Pt electrode by layer-by-layer technique. Finally, hepatitis B surface antibody (HBsAb) was electrostatically adsorbed on the gold nanoparticles surface. Electrochemical behavior of the {Au/Co(bpy)(3)(3+)}(n) multilayer film-modified electrodes was studied. Cyclic voltammetry, electrochemical impedance spectroscopy (EIS) were adopted to monitor the regular growth of the multilayer films. The performance and factors influencing the performance of the resulting immunosensors were studied in detail. The multilayer film-modified immunosensor was used for hepatitis B surface antigen (HBsAg) determination via the amperometric and potentiometric immunosensor systems, and both systems provided the same linear ranges from 0.05 to 4.5 microg/mL with different detection limits for the amperometric system 0.005 microg/mL and for the potentiometric system 0.015 microg/mL. The immunosensors were used to analyse HBsAg in human serum samples. Analytical results of clinical samples show that the developed immunoassay is comparable with the enzyme-linked immunosorbent assays (ELISAs) method, implying a promising alternative approach for detecting HBsAg in the clinical diagnosis. In addition, the multilayer films also showed better stability for 1 month at least. 相似文献
83.
Takamitsu Utsukihara Satoshi Watanabe Atsushi Tomiyama Wen Chai C. Akira Horiuchi 《Journal of Molecular Catalysis .B, Enzymatic》2006,41(3-4):103-109
Reduction of (+)-and (−)-camphorquinones (1a, 1b) by various vegetables (carrot, potato, sweet potato, apple, Japanese radish, cucumber, burdock and onion) gave -hydroxycamphor selectively. Using burdock, (+)-camphorquinone was reduced to give (−)-3S-exo-hydroxycamphor (4a) as major product in high stereoselectivity with high yield. Moreover, 1,2-cyclohexanedione (1c) and 2-methylcyclohexanone (1d) with various vegetables afford enantiomerically pure trans- and/or cis-alcohol, respectively. Various vegetable reduction gave a new idea of a biotechnological process. 相似文献
84.
Neutrophils differentially attenuate immune response to Aspergillus infection through complement receptor 3 and induction of myeloperoxidase 下载免费PDF全文
85.
Xiaohong Xia Xiaolin Liu Renjie Chai Qiong Xu Zhenyu Luo Jielei Gu Yangshuo Jin Tumei Hu Cuifu Yu Bijun Du Hongbiao Huang Wenchao Ou Shiming Liu Ningning Liu 《The Journal of biological chemistry》2021,297(5)
The underlying mechanism of neointima formation remains unclear. Ubiquitin-specific peptidase 10 (USP10) is a deubiquitinase that plays a major role in cancer development and progression. However, the function of USP10 in arterial restenosis is unknown. Herein, USP10 expression was detected in mouse arteries and increased after carotid ligation. The inhibition of USP10 exhibited thinner neointima in the model of mouse carotid ligation. In vitro data showed that USP10 deficiency reduced proliferation and migration of rat thoracic aorta smooth muscle cells (A7r5) and human aortic smooth muscle cells (HASMCs). Mechanically, USP10 can bind to Skp2 and stabilize its protein level by removing polyubiquitin on Skp2 in the cytoplasm. The overexpression of Skp2 abrogated cell cycle arrest induced by USP10 inhibition. Overall, the current study demonstrated that USP10 is involved in vascular remodeling by directly promoting VSMC proliferation and migration via stabilization of Skp2 protein expression. 相似文献
86.
Ke Zan Xiao-Qing Chen Xing-Yun Chai Qing Wu Qiang Fu Si-Xiang Zhou Peng-Fei Tu 《Phytochemistry letters》2012,5(2):313-315
Two new eudesmane sesquiterpenoids artanoate (1) and eudesmanomolide (2) were isolated from the aerial parts of Artemisia anomala S. Moore. Their structures were elucidated as methyl (4R, 5S, 6S, 7S, 10R)-1-oxo-4, 6-dihydroxy-eudesma-2, 11 (13)-dien-12-oate (1) and (1R, 5R, 6R, 10R)-3, 13-diacetoxy-1-hydroxy-3, 7(11)-diene-12, 6-olide (2) on the basis of extensive spectroscopic analyses. Compound 1 showed cytotoxicity against HCT-8 cell lines with IC50 value of 9.13 μM, and compound 2 exhibited inhibitory activities against HCT-8 and A549 cell lines with IC50 values of 3.76 and 5.49 μM, respectively. 相似文献
87.
Chun-Kuei Su Chiu-Ming Ho Hsiao-Hui Kuo Yu-Chuan Wen Chok-Yung Chai 《Journal of biomedical science》2009,16(1):44-14
An isolated thoracic spinal cord of the neonatal rat in vitro spontaneously generates sympathetic nerve discharge (SND) at
~25°C, but it fails in SND genesis at ≤ 10°C. Basal levels of the c-Fos expression in the spinal cords incubated at ≤ 10°C
and ~25°C were compared to determine the anatomical substrates that might participate in SND genesis. Cells that exhibited
c-Fos immunoreactivity were virtually absent in the spinal cords incubated at ≤ 10°C. However, in the spinal cords incubated
at ~25°C, c-Fos-positive cells were found in the dorsal laminae, the white matter, lamina X, and the intermediolateral cell
column (IML). Cell identities were verified by double labeling of c-Fos with neuron-specific nuclear protein (NeuN), glial
fibrillary acidic protein (GFAP), or choline acetyltransferase (ChAT). The c-Fos-positive cells distributed in the white matter
and lamina X were NeuN-negative or GFAP-positive and were glial cells. Endogenously active neurons showing c-Fos and NeuN
double labeling were scattered in the dorsal laminae and concentrated in the IML. Double labeling of c-Fos and ChAT confirmed
the presence of active sympathetic preganglionic neurons (SPNs) in the IML. Suppression of SND genesis by tetrodotoxin (TTX)
or mecamylamine (MECA, nicotinic receptor blocker) almost abolished c-Fos expression in dorsal laminae, but only mildly affected
c-Fos expression in the SPNs. Therefore, c-Fos expression in some SPNs does not require synaptic activation. Our results suggest
that spinal SND genesis is initiated from some spontaneously active SPNs, which are capable of TTX- or MECA-resistant c-Fos
expression. 相似文献
88.
Sun-Ju Byun Kyung Chul Moon Kyung-Suk Suh Joon Koo Han Jong-Yil Chai 《The Korean journal of parasitology》2010,48(2):161-165
Echinococcus granulosus, an intestinal tapeworm of dogs and other canids, infects humans in its larval stage and causes human echinococcosis or hydatid disease. In the Republic of Korea, 31 parasite-proven human echinococcosis cases have been reported, most of which were imported from the Middle East. We recently examined a 61-year-old Korean man who had a large cystic mass in his liver. ELISA was negative for tissue parasitic infections, including echinococcosis, cysticercosis, paragonimiasis, and sparganosis. The patient underwent surgery to remove the cyst, and the resected cyst was processed histopathologically for microscopic examinations. In sectioned cyst tissue, necrotizing protoscolices with disintegrated hooklets of E. granulosus were found. In some areas, only freed, fragmented hooklets were detected. The patient had traveled to western and central Europe in 1996, and had no other history of overseas travel. We report our patient as a hepatic echinococcosis case which was probably imported from Europe. 相似文献
89.
Spider venoms are complex mixtures of neurotoxicpeptides, proteins and low molecular mass organicmolecules. Their neurotoxic activity is due to the interac-tion of the venom components with cellular receptors, inparticular ion channels. Spider venoms have… 相似文献
90.
Summary Chromosomes and their relationship to nuclear components during various phases of the cell cycle were studied with different fixation, embedding, and enzyme techniques. The results showed that interphase chromosomes may have oriented in such a way that a given locus became associated with the nuclear membrane. Some chromosomes also appeared to interact with the nucleolus. The nuclear matrix materials, however, were distributed between the chromosomes and formed a delineating boundary for the chromosomes. These matrix materials, furthermore, formed channel-like structures within the nucleus and towards the cytoplasm through their interaction with nuclear pore complexes. During mitosis, chromosomes were encapsulated with material that appeared to be derived from the matrix, disintegrated residues and fragments of the nuclear envelope, the lamina, and nucleolar material. These chromosome-associated materials seen in mitosis appeared to serve as foci for formation of new nuclear components in subsequent interphase. 相似文献