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Xingyu Zhu Qianqian Gao Genhua Zhao Heng Wang Ling Liu Zhipeng Chen Yijun Chen Li Wu Zisheng Xu Weidong Li 《Biological trace element research》2018,184(1):136-147
To evaluate and compare the effect of raw and processed pyritum on tibial defect healing, 32 male Sprague Dawley rats were randomly divided into four groups. After tibial defect, animals were produced and grouped: sham and control group were orally administrated with distilled water (1 mL/100 g), while treatment groups were given aqueous extracts of raw and processed pyritum (1.5 g/kg) for successive 42 days. Radiographic examination showed that bone defect healing effect of the treatment groups was obviously superior compared to that of the control group. Bone mineral density of whole tibia was increased significantly after treating with pyritum. Inductively coupled plasma-optical emission spectrometry showed that the contents of Ca, P, and Mg in callus significantly increased in the treatment groups comparing with the control. Moreover, serological analysis showed that the concentration of serum phosphorus of the treatment groups significantly increased compared with that of the control group. By in vitro study, we have evaluated the effects of drug-containing serum of raw and processed pyritum on osteoblasts. It was manifested that both the drug-containing sera of raw and processed pyritum significantly increased the mRNA levels of alkaline phosphatase and collagen type I. Protein levels of phosphorylated Smad2/3 also increased. The mRNA levels of osteocalcin and transforming growth factor β (TGF-β) type I and II receptors, as well as the protein levels of TGF-β1 in the processed groups, were higher than those in the control. In summary, both raw and processed pyritum-containing sera exhibited positive effects on osteoblasts, which maybe via the TGF-β1/Smad signaling pathway. Notably, the tibia defect healing effect of pyritum was significantly enhanced after processing. 相似文献
3.
Sabrina Forveille Heng Zhou Allan Sauvat Lucillia Bezu Kevin Müller Peng Liu Laurence Zitvogel Gérard Pierron ?ystein Rekdal Oliver Kepp Guido Kroemer 《Cell cycle (Georgetown, Tex.)》2015,14(21):3506-3512
The oncolytic peptide LTX-315 has been designed for killing human cancer cells and turned out to stimulate anti-cancer immune responses when locally injected into tumors established in immunocompetent mice. Here, we investigated the question whether LTX-315 induces apoptosis or necrosis. Transmission electron microscopy or morphometric analysis of chromatin-stained tumor cells revealed that LTX-315 failed to induce apoptotic nuclear condensation and rather induced a necrotic phenotype. Accordingly, LTX-315 failed to stimulate the activation of caspase-3, and inhibition of caspases by means of Z-VAD-fmk was unable to reduce cell killing by LTX-315. In addition, 2 prominent inhibitors of regulated necrosis (necroptosis), namely, necrostatin-1 and cycosporin A, failed to reduce LTX-315-induced cell death. In conclusion, it appears that LTX-315 triggers unregulated necrosis, which may contribute to its pro-inflammatory and pro-immune effects. 相似文献
4.
Effects of pingyanymycin on chromosomes: a possible structural basis for chromosome aberration 总被引:2,自引:0,他引:2
Pingyanymycin (PYM), and antitumor-antibiotic complex which belongs to the bleomycin family can induce "G2-free chromatin" and "uncompleted-packing-mitotic figures" (UPM) at increased frequency after treatment of cultured human lymphocytes. PYM can also induce an extraordinarily high frequency of chromosomal breaks but few sister-chromatid exchanges (SCE) in the same experiment, which is similar to the action of bleomycin. To solve this remarkable contradiction we presume that the UPM is related to a basic mechanism for producing chromosomal aberrations. Our results also show that various steps of the chromosomal cycle can be affected by certain chemical agents, and these treatments lead to chromosomal aberrations. Thus, other testing systems should be used in addition to the SCE system. 相似文献
5.
Salas-Prato Milagros Tanguay Jean-Francois Lefebvre Yves Wojciechowicz Don Liem H. Heng Barnes David W. Ouellette Ginette Muller-Eberhard Ursula 《In vitro cellular & developmental biology. Plant》1988,24(5):470-470
In Vitro Cellular &; Developmental Biology - Plant - 相似文献
6.
A.S.C. Wan T.L. Ngiam S.L. Leung M.L. Go P.W.S. Heng P.N. Natarajan A. Shafiee M. Vossoghi F. Savabi C.G. Francisco R. Freire R. Hernandez J.A. Salazar E. Suarez G.A.Garcia De La Mora Y.Grillasca R. O. Jimeno 《Steroids》1983,41(3):309-320
The synthesis of esters of norethisterone (17α-ethynyl-17β-hydroxy-estr-4-en-3-one) with acids containing a benzene ring is described, two methods of esterification being compared in terms of yield and convenience. The activities of these esters as long-acting contraceptive agents have been evaluated. 相似文献
7.
Modes of DAPI banding and simultaneous in situ hybridization 总被引:11,自引:0,他引:11
By controlling the degree of chromatin denaturation through formamide incubation, or by heat treatment and/or by high pH, three types of high quality 4,6-diamidino-2-phenylindole (DAPI) bands can be produced sequentially on the same set of 5-bromo-2-deoxyuridine (BrdU)-incorporated chromosomes: first DAPI multibanding (the equivalent of Q-banding), then partial C-banding including distamycin A (DA)/DAPI banding, and finally C-banding pattern. It is assumed that the different DAPI-chromatin interactions following these treatments reflect the different chromatin structures at the chromosomal sites. Since the DAPI banding protocol is compatible with in situ hybridization, the combination of fluorescent in situ hybridization (FISH) with DAPI banding allows the simultaneous detection of signals from the DNA probes and the identification of the chromosomal band location of the probe. We demonstrate this useful application with the localization of the cystic fibrosis and Duchenne muscular dystrophy gene probes to their appropriate bands. 相似文献
8.
H. B. Lee J. Guillaume R. Chou G. Cuzon H. H. Heng J. Fuchs 《Zeitschrift fur angewandte Ichthyologie》1995,11(3-4):302-308
This paper describes the effort of the Marine Aquaculture Section of the Primary Production Department in Singapore and the Institut Francais de Recherche pour l'Exploitation de la Mer in developing adequate facilities for fish nutritional requirement studies in Singapore, and in introducing appropriate nutritional methodology so that results are reliable and accurate. One of the first achievements was the demonstration of homogeneous fish (tropical seabass, Lates calcarifer Bloch) growth response in a newly established tank system before any nutritional experiments were initiated. The application of statistical procedures that take into consideration the power of a test and number of replications required has allowed for more accurate interpretation of results. This can be seen in the results of the first nutritional requirement experiment on the optimal dietary protein level of the seabass at constant energy. 相似文献
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10.
The Mammalian Protein (rbet1) Homologous to Yeast Bet1p Is Primarily Associated with the Pre-Golgi Intermediate Compartment and Is Involved in Vesicular Transport from the Endoplasmic Reticulum to the Golgi Apparatus 总被引:7,自引:1,他引:6 下载免费PDF全文
Tao Zhang Siew Heng Wong Bor Luen Tang Yue Xu Frank Peter V. Nathan Subramaniam Wanjin Hong 《The Journal of cell biology》1997,139(5):1157-1168
Yeast Bet1p participates in vesicular transport from the endoplasmic reticulum to the Golgi apparatus and functions as a soluble N-ethylmaleimide–sensitive factor attachment protein receptor (SNARE) associated with ER-derived vesicles. A mammalian protein (rbet1) homologous to Bet1p was recently identified, and it was concluded that rbet1 is associated with the Golgi apparatus based on the subcellular localization of transiently expressed epitope-tagged rbet1. In the present study using rabbit antibodies raised against the cytoplasmic domain of rbet1, we found that the majority of rbet1 is not associated with the Golgi apparatus as marked by the Golgi mannosidase II in normal rat kidney cells. Rather, rbet1 is predominantly associated with vesicular spotty structures that concentrate in the peri-Golgi region but are also present throughout the cytoplasm. These structures colocalize with the KDEL receptor and ERGIC-53, which are known to be enriched in the intermediate compartment. When the Golgi apparatus is fragmented by nocodazole treatment, a significant portion of rbet1 is not colocalized with structures marked by Golgi mannosidase II or the KDEL receptor. Association of rbet1 in cytoplasmic spotty structures is apparently not altered by preincubation of cells at 15°C. However, upon warming up from 15 to 37°C, rbet1 concentrates into the peri-Golgi region. Furthermore, rbet1 colocalizes with vesicular stomatitis virus G-protein en route from the ER to the Golgi. Antibodies against rbet1 inhibit in vitro transport of G-protein from the ER to the Golgi apparatus in a dose-dependent manner. This inhibition can be neutralized by preincubation of antibodies with recombinant rbet1. EGTA is known to inhibit ER-Golgi transport at a stage after vesicle docking but before the actual fusion event. Antibodies against rbet1 inhibit ER-Golgi transport only when they are added before the EGTA-sensitive stage. These results suggest that rbet1 may be involved in the docking process of ER- derived vesicles with the cis-Golgi membrane. 相似文献