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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.
金铁锁的一个新三萜成分 总被引:20,自引:1,他引:19
金铁锁(Psammosilene tunicoides W.C.Wu et C.Y.Wu)系石竹科金铁锁属单一种植物,产于我国西南部。该植物为传统中药,具止血、止痛、活血等多种功效。其根部富含皂甙成分,有镇痛、抗炎和抑菌等生理活性。我们曾报道了将其根中提取的粗皂甙酸性水解后,分离到的六个齐墩果酸型三萜皂甙元。本文报道从中分离到的另一新三萜成分:3-hydroxy-12,14-diene-27-nordeane-28-nic acid。 相似文献
5.
仙茅属三个国产种的核型研究 总被引:1,自引:0,他引:1
本文报道了中国产三种仙茅植物的核型。1.绒叶仙茅Curculigo crassifolia (Baker) Hook. f., 2n=2x=18=10m(4SAT) 8 sm;2.大叶仙茅C.capitulata(Lour.)O. Kuntze,2n=2x=18=10(2SAT) 8sm;3.中华仙茅C.sinensis S.C.Chen,2n=2x=18=8m(3SAT) 10sm(2SAT)。其中中华仙茅的核型为首次报道。虽然三种仙茅的核型都是“2B”型,但中华仙茅的核型不对称性比绒叶仙茅和大叶仙茅强。 相似文献
6.
米团花的化学成分研究 总被引:2,自引:0,他引:2
从米团花(Leucosceptrum canum Smith)鲜叶中分到三个化学成分,经光谱测定和化学反应已确定它们的化学结构分别为异香紫苏醇(isosclaveol)Ⅰ;柳穿鱼黄素(pectolinarigenin)Ⅱ;β-谷甾醇(β-sitosterol)Ⅲ。其中化合物Ⅰ为新的天然存在的labdane类型二萜化合物。 相似文献
7.
Forty different chiral molecules were studied by liquid chromatography with a Pirkle-type, (R)-N-(3,5-dinitrobenzoyl) phenylglycine (DNBPG), chiral stationary phase column. The dramatic effect of a small molecular change on chiral recognition was demonstrated using DL-amino acid derivatives. The inductive effect on chiral recognition was also studied using trifluoro-, trichloro-, dichloro-, monochloroacetyl, and acetyl derivatives of four different chiral amines. The study of the enantiomer separation of 11 different crown ethers of 2,2′-binaphthyldiyl showed that the rigidity of the chiral center can be an additional parameter in chiral recognition for the DNBPG phase but not for a β-cyclodextrin bonded chiral phase. It is apparent from this study that steric effects, inductive effects, and molecular rigidity play important roles in chiral recognition with DNBPG chiral stationary phases. 相似文献
8.
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
9.
我国沙漠中部地区主要不同生态类型植物脯氨酸的累积、光合、呼吸和叶绿素含量 总被引:21,自引:0,他引:21
中生植物脯氨酸含量为0.42mg/g.dw, 低于少浆旱生植物(1.73mg/g.dw)。多浆旱生植物脯氨酸含量最高(7.22mg/g.dw),为前两者的17倍和4倍,两类旱生植物在干旱条件下(非灌溉)脯氨酸含量均高于灌水处理。少浆与多浆旱生植物的光合强度(16.74,14.04CO2mg/g.dw.h)差异不大,而中生植物(37.57mg/g.dW.h)略高于多浆旱生植物(4.73CO2Mg/g.dw.h),与中生植物(7.60Co2mg/g.dw.h)接近,光合/呼吸值,少浆,多浆与中生植物分别为2.50,3.09和4.59,说明中生植物的合成明显大于消耗,季节动态中,中生植物显著高于两类旱生植物,叶绿素总量三类植物差异甚微。 相似文献
10.
一、前言哈巴德布鲁克实验林(Hubbard Brook Experimental Forest)位于美国东北部新罕布什尔州中部的白山国家森林中。该地区位于典型温带湿润气候区内,年平均降水量为129.5cm,全年月平均降水量变化不大,冬雪夏雨。蒸发蒸腾量以每年6—9月为最大(Likens等,1977;Bormann等,1979)。该实验林为北美温带落叶阔叶林,属红果云杉(Picea rubens)-阔叶林。Hubbard Brook Ecosystem Study(HBES)是开始最 相似文献