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1. chinaXiv:201906.00028 [pdf]

Cladistic approach on chronological relationship of the Pleistocene mammalian faunas from China

DONG Wei; LIU Wen-Hui; BAI Wei-Peng
Subjects: Biology >> Zoology

There are many localities yielding the Pleistocene mammalian faunas in China. It offers excellent material for the study of mammalian evolution, biochronology,paleoecology,paleoenvironment, paleozoogeography, etc. Faunal assemblage characters and taxonomic extinction rates were widely used for determining the faunal ages in biochronology. Faunal binary similarity coefficients sequenced according to Brainerd-Robinson’s rule and antiquity coefficients were further developed methods in biochronology for dating the faunal ages. The faunal binary similarity coefficients are based on the presence or absence of a taxon in a fauna. It is similar to the presence or absence of a character of a species in cladistic analyses for phylogeny, and all faunas have a special ancestor-descendant relationship. The present work is an attempt to find the relationship of the faunas with cladistic methods by selecting three groups of faunas sequenced by faunal binary similarity coefficients according to Brainerd-Robinson’s rule and antiquity coefficients, to compare the results with different methods, and then to estimate the ages of the faunas not yet dated by physical or chemical methods. The estimations are as follow: Gulongshan in Dalian, Liaoning Province: 16–20 ka; Shanchengzi at Benxi, Liaoning Province: 20–30 ka; Hualongdong at Dongzhi Man site, Anhui Province: 150–400 ka; Xinghuashan at Nanzhao Man site, Henan Province: 150–400 ka; Donghe at Luonan Man site, Shaanxi Province: 500–700 ka; Bailongdong at Yunxi Man site, Hubei Province: 500–850 ka; Meipu at Yunxian, Hubei Province: 500–850 ka; Mohui at Tiandong Man site, Guangxi Autonomous Region: 1.2–1.8 Ma; Juyuandong at Liucheng, Guangxi Autonomous Region: 1.2–1.5 Ma; Chutoulang at Chifeng, Nei Mongol Autonomous Region: 1.6–1.9 Ma; Renzidong at Fanchang, Anhui Province: 1.9–2.4 Ma.

submitted time 2019-06-11 From cooperative journals:《古脊椎动物学报》 Hits95Downloads53 Comment 0

2. chinaXiv:201803.00011 [pdf]

New material of the Late Miocene Moschus (Artiodactyla, Mammalia) from Huade, Nei Mongol, North China

DONG Wei; LIU Wen-Hui; ZHANG Li-Min; BAI Wei-Peng; CAI Bao-Quan
Subjects: Geosciences >> Geology

Moschus grandaevus was firstly uncovered from the Late Miocene deposits at Ertemte, Olan Chorea, Harr Obo and Hua Ba in or around Huade County in the middle part of Nei Mongol and was described by Schlosser in 1924. The excavations by Sino-Soviet Joint Paleontological Team in 1959 and recent excavations since 2013 at Tuchengzi (Tuchetse), another locality at Huade, accumulated many specimens of the musk deer. The morphology and metric studies show that the musk deer specimens from Tuchengzi are the same as those described by Schlosser and can be included into the same species. M. grandaevus ranges from Siberia of Russia to North China, and likely to southern China, in the Late Miocene and Pliocene. The appearance of such folivorous musk deer in the Late Miocene deposits at Tuchengzi indicates that there were forests there during that period. The cladistic analyses show that the fossil species of Moschus are closely related to each other and can be grouped together as Moschini or Moschinae. Micromeryx is closer to Moschus and Cervidae, but the relationship between Micromeryx and Moschus is more complicated than previously considered; nonetheless Hispanomeryx is closer to Bovidae. Schlosser (1924)记述了最初发现于内蒙古化德境内或附近的二登图、敖兰卓蕾、哈尔敖包及华坝的古麝(Moschus grandaevus)。1959年中苏古生物考察队在化德的另一个地点土城子采集到不少古麝化石。2013年以来作者在土城子进行的野外发掘积累了更多的古麝化石标本。土城子标本在形态和测量数据方面和二登图等地点的古麝非常接近,可以归入同一种。根据现有资料归纳,古麝的地理分布范围自俄罗斯的西伯利亚到华北,很可能延伸到华南;其地质时代分布范围为晚中新世–上新世。食叶型古麝在土城子晚中新世地层中的出现说明当时土城子一带有森林环境。支序分析显示麝属(Moschus)化石种相互之间的系统关系非常近,可以归并为麝族(Moschini)或麝亚科(Moschinae); Micromeryx更接近麝属和鹿科,它与麝属之间的关系比以前认为的复杂,而Hispanomeryx更接近牛科。

submitted time 2018-03-02 From cooperative journals:《古脊椎动物学报》 Hits4228Downloads742 Comment 0

3. chinaXiv:201605.01740 [pdf]

Aberrantly upregulated TRAP1 is required for tumorigenesis of breast cancer

Zhang, Bo; Wei, Peng; Hao, Junfeng; Zhao, Lijing; Zhang, Fenglin; Wei, Taotao; Wang, Jing; Huang, Zhen; Wei, Peng; Liu, Ying; Tu, Yaping
Subjects: Biology >> Biophysics >> Oncology

Tumor necrosis factor receptor-associated protein 1 (TRAP1) is abnormally expressed in many cancers. In this study, we showed that TRAP1 is aberrantly upregulated in breast tumors compared to control tissues. TRAP1 knockdown downregulates mitochondrial aerobic respiratory, sensitizes cells to lethal stimuli, and inhibited tumor growth in MDA-MB-231 and MCF-7 breast cancer cells in vivo. TRAP1 overexpression, however, enhances the capacity to cope with stress conditions. These evidences suggested that TRAP1 is required for tumorigenesis. We also found that TRAP1 regulates the mitochondrial morphology. Relatively lower TRAP1 levels are associated with the rod-shaped mitochondrial phenotype in invasive and metastatic MDA-MB-231 breast cancer cells; on the contrary, higher TRAP1 levels are associated with the tubular network-shaped mitochondrial phenotype in non-invasive MCF-7 cells. Interestingly, the expression of TRAP1 in human breast cancer specimens inversely correlates with tumor grade. Overexpression of TRAP1 in MDA-MB-231 cells causes mitochondrial fusion, triggers mitochondria to form tubular networks, and suppresses cell migration and invasion in vitro and in vivo. These data link TRAP1-regulated mitochondrial dynamics and function with tumorigenesis of breast cancer and suggested that TRAP1 may therefore be a potential target for breast cancer drug development.

submitted time 2016-05-15 Hits1027Downloads481 Comment 0

4. chinaXiv:201605.01418 [pdf]

Linear-dendrimer type methoxy-poly (ethylene glycol)-b-poly (epsilon-caprolactone) copolymer micelles for the delivery of curcumin

Song, Zhimei; Zhu, Wenxia; Yang, Fengying; Liu, Na; Feng, Runliang; Zhu, Wenxia; Song, Jiarong; Wei, Peng
Subjects: Biology >> Biophysics

Purpose: To improve curcumin's pharmacokinetic, in vitro cytotoxicity and release property. Methods: A novel linear-dendrimer methoxy-poly (ethylene glycol)-b-poly (epsilon-caprolactone) copolymer was synthesized through O-alkylation, basic hydrolysis and ring-opening polymerization reaction with methoxy-poly (ethylene glycol), epichlorohydrin and epsilon-caprolactone as raw materials. Its structure was characterized by 1 H-NMR and GPC. The copolymer's hemolysis and micellar encapsulation for curcumin by thin-film hydration were studied. Curcumin-loaded micelles were evaluated by use of in vitro release, FT-IR and X-ray diffraction. Curcumin-loaded micelles' in vitro cytotoxic activities against Hela and HT-29 cells were done, and its pharmacokinetic parameters were also carried out. Results: Curcumin was encapsulated into the micelles with 92.54% of entrapment efficiency and 12.84% of drug loading in amorphous forms. The dissolubility of nanoparticulate curcumin was 1.70 x 10(5) times higher than that of curcumin in water. The obtained copolymer showed no hemolysis. In vitro drug release study indicated that, in all cases, the kinetics was adjusted well to the Makoid-Banakar model (R-abj(2) = 0.9984). In addition, data were analyzed by the Korsmeyer-Peppas model, n values were 0.43, indicating that the drug release was accomplished by the combination diffusion and polymer chain relaxation. The cytotoxicity experiment indicated that the nanoparticulate curcumin kept up its potent anti-cancer activities. The pharmacokinetic results showed that the MRT0-infinity, t(1/2z) and AUC(0-infinity) of Curcumin-loaded micelles were 1.64, 6.54 and 4.67 times higher than that of CUR control solution. Conclusions: The copolymeric micelles loading curcumin might act as a delivery vehicle for CUR.

submitted time 2016-05-12 Hits374Downloads244 Comment 0

5. chinaXiv:201605.01413 [pdf]

Lysine Malonylation Is Elevated in Type 2 Diabetic Mouse Models and Enriched in Metabolic Associated Proteins

Du, Yipeng; Zhou, Bo; He, Xiaolong; Wei, Peng; Liu, Pingsheng; Wei, Taotao; Cai, Tanxi; Xue, Peng; Yang, Fuquan; Cai, Tanxi; Xue, Peng; Yang, Fuquan; Li, Tingting; Cai, Tanxi; Zhou, Bo; He, Xiaolong; Wei, Peng
Subjects: Biology >> Biophysics

Protein lysine malonylation, a newly identified protein post-translational modification (PTM), has been proved to be evolutionarily conserved and is present in both eukaryotic and prokaryotic cells. However, its potential roles associated with human diseases remain largely unknown. In the present study, we observed an elevated lysine malonylation in a screening of seven lysine acylations in liver tissues of db/db mice, which is a typical model of type 2 diabetes. We also detected an elevated lysine malonylation in ob/ob mice, which is another model of type 2 diabetes. We then performed affinity enrichment coupled with proteomic analysis on liver tissues of both wild-type (wt) and db/db mice and identified a total of 573 malonylated lysine sites from 268 proteins. There were more malonylated lysine sites and proteins in db/db than in wt mice. Five proteins with elevated malonylation were verified by immunoprecipitation coupled with Western blot analysis. Bioinformatic analysis of the proteomic results revealed the enrichment of malonylated proteins in metabolic pathways, especially those involved in glucose and fatty acid metabolism. In addition, the biological role of lysine malonylation was validated in an enzyme of the glycolysis pathway. Together, our findings support a potential role of protein lysine malonylation in type 2 diabetes with possible implications for its therapy in the future.

submitted time 2016-05-12 Hits512Downloads328 Comment 0

6. chinaXiv:201605.01320 [pdf]

Y-shaped biotin-conjugated poly (ethylene glycol)-poly (epsilon-caprolactone) copolymer for the targeted delivery of curcumin

Zhu, Wenxia; Teng, Fangfang; Zhu, Wenxia; Teng, Fangfang; Song, Zhimei; Meng, Ning; Yang, Fengying; Liu, Na; Feng, Runliang; Wei, Peng
Subjects: Biology >> Biophysics

In order to improve curcumin's low water-solubility and selective delivery to cancer, we reported ligand-mediated micelles based on a Y-shaped biotin-poly (ethylene glycol)-poly (epsilon-caprolactone)(2) (biotin-PEG-PCL2) copolymer. Its structure was characterized by H-1 NMR. The blank and drug-loaded micelles obtained by way of thin-film hydration were characterized by dynamic light scattering, X-ray diffraction, infrared spectroscopy and hemolytic test. Curcumin was loaded into micelles with a high encapsulating efficiency (93.83%). Curcumin's water-solubility was enhanced 170,400 times higher than free curcumin. Biotin-PEG-PCL2 micelles showed slower drug release in vitro than H2N-PEG-PCL2 micelles. In vitro cellular uptake and cytotoxicity tests showed that higher dosage of curcumin might overcome the effect of slow release on cytotoxicities because of its higher uptake induced by biotin, resulting in higher anticancer activities against MDA-MB-436 cells. In brief, Y-shaped biotin-PEG-PCL2 is a promising delivery carrier for anticancer drug. (C) 2014 Elsevier Inc. All rights reserved.

submitted time 2016-05-11 Hits238Downloads167 Comment 0

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