76 research outputs found

    On the relation between the mass of Compact Massive Objects and their host galaxies

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    Supermassive black holes and/or very dense stellar clusters are found in the central regions of galaxies. Nuclear star clusters are present mainly in faint galaxies while upermassive black holes are common in galaxies with masses 1010\geq 10^{10} M_\odot . In the intermediate galactic mass range both types of central massive objects (CMOs) are found. Here we present our collection of a huge set of nuclear star cluster and massive black hole data that enlarges significantly already existing data bases useful to investigate for correlations of their absolute magnitudes, velocity dispersions and masses with structural parameters of their host galaxies. In particular, we directed our attention to some differences between the correlations of nuclear star clusters and massive black holes as subsets of CMOs with hosting galaxies. In this context, the mass-velocity dispersion relation plays a relevant role because it seems the one that shows a clearer difference between the supermassive black holes and nuclear star clusters. The MMBHσM_{MBH}-{\sigma} has a slope of 5.19±0.285.19\pm 0.28 while MNSCσM_{NSC}-{\sigma} has the much smaller slope of 1.84±0.641.84\pm 0.64. The slopes of the CMO mass- host galaxy B magnitude of the two types of CMOs are indistinguishable within the errors while that of the NSC mass-host galaxy mass relation is significantly smaller than for supermassive black holes. Another important result is the clear depauperation of the NSC population in bright galaxy hosts, which reflects also in a clear flattening of the NSC mass vs host galaxy mass at high host masses.Comment: 12 pages, 22 figures, 2 tables, accepted for publication in MNRA

    A Preliminary Study of the Microbial Resources and Their Biological Activities of the East China Sea

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    East China Sea is one of the four sea areas in China, which possesses peculiar ecological environment and many kinds of living creatures, especially the microorganisms. We established the East China Sea microorganism library (during 2006–2010) for the first time, which stored about 30000 strains that covered most kinds of the species. In this paper, 395 pure strains of East China Sea microorganism library which belong to 33 different genera were mainly introduced. Sulfitobacter, Halomonas, Bacillus, Pseudoalteromonas, and Idiomarina were the most dominant species. On the large-scale biological activity screening of the 395 strains, 100 strains possess different biological activities based on different screening models, of which 11.4% strains have antibacterial activities, 15.9% have cytotoxicity activities, and 6.1% have antioxidation activities. Besides, the secondary metabolites of 6 strains with strong biological activities were studied systematically; diketopiperazines and macrocyclic lactones are the active secondary metabolites. The species and the biological activity of microorganisms diversity, the abundant structure type of the secondary metabolites, and their bioactivities all indicate that East China Sea is a potent marine microorganisms-derived developing resource for drug discovery

    Interleukin-11 Promotes the Progress of Gastric Carcinoma via Abnormally Expressed Versican

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    Versican, a ubiquitous component of the extracellular matrix (ECM), accumulates both in tumor stroma and cancer cells and is highly regulated by various cytokines. The aberrant expression of versican and its isoforms is known to modulate cell proliferation, differentiation, and migration, all of which are features of the invasion and metastasis of cancer; versican is also known to favour the homeostasis of the ECM. Interleukin-11 (IL-11) is an important cytokine that exhibits a wide variety of biological effects in gastric cancer development. Here, we analysed the expression of versican isoforms and found that the major isoforms expressed by both gastric carcinoma tissue and gastric cell lines were V0 and V1, and V1 was significantly higher in gastric carcinoma tissue. The treatment of the gastric cell lines AGS and MKN45 with rhIL-11 resulted in a significant increase in the expression of V0 and V1. Exogenous IL-11 increased migration in AGS and MKN45 cells, whereas these effects were reversed when the expression of V0 and V1 were abolished by siRNA targeting versican V0/V1. Collectively, these findings suggest that the abnormally expressed versican and its isoforms participate, at least in part, in the progress of gastric carcinoma triggered by IL-11

    Pro-angiogenic Role of Danqi Pill Through Activating Fatty Acids Oxidation Pathway Against Coronary Artery Disease

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    Coronary artery disease (CAD) is one of the leading causes of deaths worldwide. Energy metabolism disorders, including a reduction in fatty acids oxidation and upregulation of glycolysis pathway, are involved in the process of CAD. Therapeutic angiogenesis has become a promising treatment for CAD. Traditional Chinese medicines, such as Danqi Pill (DQP), have been proven to be effective in treating CAD in China for many years. However, the pro-angiogenic effects of DQP based on fatty acids oxidation are still unknown and the mechanism is worthy of investigation. In this study, left anterior descending (LAD) coronary artery was ligated to induce the CAD models in vivo, and cardiac functions were examined using echocardiography. Human umbilical vein endothelial cells (HUVEC) were subjected to H2O2-induced oxidative stress in vitro. The effects of DQP on CAD rat models and in vitro HUVEC were detected. Our results showed that DQP had cardio-protective effects in rat model. The intensity of capillaries in the marginal area of infarction of the rat heart was increased remarkably in DQP group, and the expression of PPARα and VEGF-2 were increased. The key enzymes involved in the transportation and intake of fatty acids, including CPT1A and CD36, both increased. In H2O2-induced endothelial cells injury models, DQP also showed protective roles and promoted capillary-like tube formation. DQP up-regulated key enzymes in fatty acids oxidation in H2O2-treated HUVEC. In addition, inhibition of CPT1A compromised the pro-angiogenic effects of DQP. In conclusion, fatty acids oxidation axis PPARα-CD36-CPT1A was involved in the pro-angiogenic roles of DQP against CAD. Cardiac CPT1A may serve as a target in therapeutic angiogenesis in clinics

    Simple Cholecystectomy Is Adequate for Patients With T1b Gallbladder Adenocarcinoma < 1 cm in Diameter

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    Purpose: Consensus-based clinical guidelines recommend that simple cholecystectomy (SC) is adequate for T1a gallbladder adenocarcinoma (GBA), but extended cholecystectomy (EC), SC plus lymphatic dissection, should be considered for T1b and more advanced GBA. Whether lymphatic dissection is necessary for the treatment of T1b GBA remains controversial. This study attempts to better define the current criteria for local treatment of T1b GBA, by examining the relationship between lymph node (LN) metastasis and tumor size in such patients.Patients and methods: Clinical data from patients with T1b GBA receiving curative surgical treatment between 2004 and 2015 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Baseline characteristics for the entire cohort were described, and overall survival (OS) and cancer-specific survival (CSS) were analyzed with the Kaplan–Meier method.Results: In total, 277 patients were enrolled for further analysis; 127 underwent lymphadenectomy. Among them, 23 patients had tumors &lt;1 cm in diameter, none of which had LN metastasis; 104 patients had tumors ≥1 cm, 15 of which had positive LNs. In the group with tumor size &lt;1 cm, there was no significant survival difference between treatment with SC or EC (P = 0.694). A clinical benefit was observed in T1b GBA patients with a tumor size ≥1 cm receiving EC vs. those receiving SC (P = 0.012).Conclusion: SC was adequate for treatment of T1b GBA &lt; 1 cm in diameter. This evidence may be included as part of current guidelines

    Association between Long-Term Changes in Dietary Percentage of Energy from Fat and Obesity: Evidence from over 20 Years of Longitudinal Data

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    Objectives: This study assessed the associations between long-term trajectories of percentage of energy from fat (PEF) and obesity among Chinese adults. Methods: Longitudinal data collected by the China Health and Nutrition Survey from 1991 to 2015 were analyzed. A body mass index ≥28.0 was defined as general obesity. Participants’ baseline PEF levels were categorized as lower than the recommendation of the Chinese Dietary Guideline (20%), meeting the recommendation (20−30%), and higher than the recommendation (>30%). Patterns of PEF trajectories were identified by latent class trajectory analysis for overall participants and participants in different baseline PEF groups, respectively. Cox proportional hazards regression models with shared frailty were used to estimate associations between PEF and obesity. Results: Data on 13,025 participants with 72,191 visits were analyzed. Four patterns of PEF trajectory were identified for overall participants and participants in three different baseline PEF groups, respectively. Among overall participants, compared with “Baseline Low then Increase Pattern” (from 12% to 20%), participants with “Baseline Normal-Low then Increase-to-High Pattern” (from 20% to 32%) had a higher hazard of obesity (hazard ratio (HR) and 95% confident interval (CI) at 1.18 (1.01−1.37)). Compared with the “Stable Pattern” group (stable at around 18% and 22%, respectively), participants with “Sudden-Increase Pattern” (from 18% to 30%) in the baseline group whose PEF levels were lower than the recommendation and those with “Sudden-Increase then Decrease Pattern” (rapidly increased from 25% to 40%, and then decreased) in the baseline group who met the recommendation had higher hazards of obesity (HRs and 95% CIs being 1.65 (1.13−2.41) and 1.59 (1.03−2.46), respectively). Conclusions: Adults with a trajectory that involved a sudden increase to a high-level PEF had a higher risk of general obesity. People should avoid increasing PEF suddenly

    Down-Regulation of MiR-127 Facilitates Hepatocyte Proliferation during Rat Liver Regeneration

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    Liver regeneration (LR) after partial hepatectomy (PH) involves the proliferation and apoptosis of hepatocytes, and microRNAs have been shown to post-transcriptionally regulate genes involved in the regulation of these processes. To explore the role of miR-127 during LR, the expression patterns of miR-127 and its related proteins were investigated. MiR-127 was introduced into a rat liver cell line to examine its effects on the potential target genes Bcl6 and Setd8, and functional studies were undertaken. We discovered that miR-127 was down-regulated and inversely correlated with the expression of Bcl6 and Setd8 at 24 hours after PH, a time at which hypermethylation of the promoter region of the miR-127 gene was detected. Furthermore, in BRL-3A rat liver cells, we observed that overexpression of miR-127 significantly suppressed cell growth and directly inhibited the expression of Bcl6 and Setd8. The results suggest that down-regulation of miR-127 may be due to the rapid methylation of its promoter during the first 24 h after PH, and this event facilitates hepatocyte proliferation by releasing Bcl6 and Setd8. These findings support a miRNA-mediated negative regulation pattern in LR and implicate an anti-proliferative role for miR-127 in liver cells

    Application of Gene Knockout and Heterologous Expression Strategy in Fungal Secondary Metabolites Biosynthesis

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    The in-depth study of fungal secondary metabolites (SMs) over the past few years has led to the discovery of a vast number of novel fungal SMs, some of which possess good biological activity. However, because of the limitations of the traditional natural product mining methods, the discovery of new SMs has become increasingly difficult. In recent years, with the rapid development of gene sequencing technology and bioinformatics, new breakthroughs have been made in the study of fungal SMs, and more fungal biosynthetic gene clusters of SMs have been discovered, which shows that the fungi still have a considerable potential to produce SMs. How to study these gene clusters to obtain a large number of unknown SMs has been a research hotspot. With the continuous breakthrough of molecular biology technology, gene manipulation has reached a mature stage. Methods such as gene knockout and heterologous expression techniques have been widely used in the study of fungal SM biosynthesis and have achieved good effects. In this review, the representative studies on the biosynthesis of fungal SMs by gene knockout and heterologous expression under the fungal genome mining in the last three years were summarized. The techniques and methods used in these studies were also briefly discussed. In addition, the prospect of synthetic biology in the future under this research background was proposed
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