49 research outputs found
The candidate tumor suppressor gene ECRG4 inhibits cancer cells migration and invasion in esophageal carcinoma
<p>Abstract</p> <p>Background</p> <p>The esophageal cancer related gene 4 (ECRG4) was initially identified and cloned in our laboratory from human normal esophageal epithelium (GenBank accession no.<ext-link ext-link-id="AF325503" ext-link-type="gen">AF325503</ext-link>). ECRG4 was a new tumor suppressor gene in esophageal squamous cell carcinoma (ESCC) associated with prognosis. In this study, we investigated the novel tumor-suppressing function of ECRG4 in cancer cell migration, invasion, adhesion and cell cycle regulation in ESCC.</p> <p>Methods</p> <p>Transwell and Boyden chamber experiments were utilized to examined the effects of ECRG4 expression on ESCC cells migration, invasion and adhesion. And flow cytometric analysis was used to observe the impact of ECRG4 expression on cell cycle regulation. Finally, the expression levels of cell cycle regulating proteins p53 and p21 in human ESCC cells transfected with ECRG4 gene were evaluated by Western blotting.</p> <p>Results</p> <p>The restoration of ECRG4 expression in ESCC cells inhibited cancer cells migration and invasion (<it>P </it>< 0.05), which did not affect cell adhesion capacity (<it>P </it>> 0.05). Furthermore, ECRG4 could cause cell cycle G1 phase arrest in ESCC (<it>P </it>< 0.05), through inducing the increased expression of p53 and p21 proteins.</p> <p>Conclusion</p> <p>ECRG4 is a candidate tumor suppressor gene which suppressed tumor cells migration and invasion without affecting cell adhesion ability in ESCC. Furthermore, ECRG4 might cause cell cycle G1 phase block possibly through inducing the increased expression of p53 and p21 proteins in ESCC.</p
Recommended from our members
On the origin of vertebrate body plan: Insights from the endoderm using the hourglass model
The vertebrate body plan is thought to be derived during the early Cambrian from a worm-like chordate ancestor. While all three germ layers were clearly involved in this innovation, the role of the endoderm remains elusive. According to the hourglass model, the optimal window for investigating the evolution of vertebrate endoderm-derived structures during cephalochordate development is from the Spemann\u27s organizer stage to the opening of the mouth (Stages 1–7, described herein). Regulatory gene expression, examined during these stages, illustrate that the cephalochordate endoderm is patterned into 12 organ primordia. Early vertebrates inherited at least a portion of 6 of these primordia, while the remainder were lost. Of those that were preserved, we demonstrate that the vertebrate symmetric mouth was built on a vestige of the anterior pre-oral pit, that the pre-existing pharyngeal pouch in this chordate ancestor laid the foundation for the new neural crest cell (NCC)-derived vertebrate-type pharyngeal arches, that the thyroid evolved from the posterior endostyle primordim, that the pancreas was derived from the Pdx1-expressing diverticulum primordium, and the small and large intestines originated with the Cdx1-expressing hindgut rudiments. This investigation uncovers the evolutionary foundations of vertebrate endoderm-derived structures, and demonstrates that the number of organ primordia were reduced during evolution
Contact-hardening behavior of calcium silicate hydrate powders
Calciumsilicate hydrate (C-S-H) synthesized by a hydrothermal process fromlime and siliceous materials was oven-dried and compressed into compacts. The microstructure and compaction properties of the resulting powderswere characterized. The results showthat the powders containing an amorphous structure become hardened compacts immediately after compression. Compacts with high strength but a relatively lower bulk density were produced. Amorphous C-S-H plays a key role in the bonding formation during powder compaction. According to the Heckel plots, particle rearrangement and plastic deformation were involved in the compaction of C-S-H powders. Point contact between C-S-H particles due to particle rearrangement dominates at a low compression pressure (i.e., < 20MPa). Van derWaals forces and hydrogen bonding are the main bonding types. Plastic deformation occurs at a higher compression pressure (i.e., > 60MPa), which results in surface contact. Consequently, a solid bridge forms, and the strength of compacts increases rapidly. These findings provide novel insight into the utilization of materials containing amorphous calcium silicate hydrate
Optimization of Total Flavonoid Compound Extraction from Gynura medica Leaf Using Response Surface Methodology and Chemical Composition Analysis
Optimization of total flavonoid compound (TFC) extraction from Gynura medica leaf was investigated using response surface methodology (RSM) in this paper. The conditions investigated were 30–60% (v/v) ethanol concentration (X1), 85–95 °C extraction temperature (X2) and 30–50 (v/w) liquid-to-solid ratio (X3). Statistical analysis of the experiments indicated that temperature and liquid-to-solid ratio significantly affected TFC extraction (p < 0.01). The Box-Behnken experiment design showed that polynomial regression models were in good agreement with the experimental results, with the coefficients of determination of 0.9325 for TFC yield. The optimal conditions for maximum TFC yield were 55% ethanol, 92 °C and 50 (v/w) liquid-to-solid ratio with a 30 min extraction time. Extracts from these conditions showed a moderate antioxidant value of 54.78 μmol quercetin/g dry material (DM), 137.3 μmol trolox/g DM for 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 108.21 μmol quercetin/g DM, 242.31 μmol trolox/g DM for 2,2-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS+), respectively. HPLC-DAD-MS analysis showed that kaempferol-3-O-glucoside was the principal flavonoid compound in Gynura medica leaf
Tracking the Evolution of HIV/AIDS in China from 1989–2009 to Inform Future Prevention and Control Efforts
BACKGROUND: To determine policy implications, this analysis tracks the evolution of HIV/AIDS infection across China to understand current trends and potential risk factors. METHODS AND PRINCIPAL FINDINGS: A retrospective study with spatial analytical model and multilevel spatial models was conducted among 326,157 HIV/AIDS cases reported from 1989-2009. The results indicate that the distribution of HIV/AIDS was clustered at the county level with different directional distributions across China from 2003 to 2009. Compared to 2003, by 2009 there was a 122% increase in HIV cases among rural residents, 294% increase among urban residents, 211% increase among migrants, and 237% increase among permanent residents. The overall proportion of HIV by different routes of transmission showed dramatic changes with a 504% increase in sexual transmission of HIV, 90% decrease in blood/plasma transmission, and 35% decrease in injecting drug user transmission. Sexual transmission was the major transmission route among women (44%) and the elderly (59% in men, 44% in women) as well as among permanent (36%) and urban residents (33%). Among those <65 years old, women increased more than men, but among those ≥ 65 years, men increased more than women. Migrants contributed to the variance of HIV infection between counties but not within counties. The length of highway and urbanization combined with illiteracy were risk factors for HIV/AIDS. CONCLUSIONS/SIGNIFICANCE: Rates of HIV/AIDS among permanent urban residents, particularly women and elderly men, have increased significantly in recent years. To prevent HIV from spreading further among the general population, additional attention should be paid to these populations as well as to migrants
Automatic 3D tooth segmentation using convolutional neural networks in harmonic parameter space
Automatic segmentation of 3D tooth models into individual teeth is an important step in orthodontic CAD systems. 3D tooth segmentation is a mesh instance segmentation task. Complex geometric features on the surface of 3D tooth models often lead to failure of tooth boundary detection, so it is difficult to achieve automatic and accurate segmentation by traditional mesh segmentation methods. We propose a novel solution to address this problem. We map a 3D tooth model isomorphically to a 2D harmonic parameter space and convert it into an image. This allows us to use a CNN to learn a highly robust image segmentation model to achieve automated and accurate segmentation of 3D tooth models. Finally, we map the image segmentation mask back to the 3D tooth model and refine the segmentation result using an improved Fuzzy Clustering-and-Cuts algorithm. Our method has been incorporated into an orthodontic CAD system, and performs well in practice
New Cretaceous Lacewings in a Transitional Lineage of Myrmeleontoidea and Their Phylogenetic Implications
The extinct neuropteran families Cratosmylidae and Babinskaiidae hitherto only known from the Cretaceous represent the transitional lineage between Nymphidae and advanced myrmeleontoids (e.g., Nemopteridae and Myrmeleontidae) in the superfamily Myrmeleontoidea. Here, we describe two new species, which respectively belong to Cratosmylidae and Babinskaiidae, namely, Araripenymphes burmanus sp. nov. and Paradoxoleon chenruii gen. et sp. nov., from the mid-Cretaceous Kachin amber of Myanmar. Cratosmylidae, which was previously only recorded from the Lower Cretaceous of Brazil (Crato Formation), is first reported from the mid-Cretaceous Kachin amber of Myanmar, and the co-occurrence of Araripenymphes Menon, Martins-Neto and Martill, 2005 across South America and Asia further documents the Gondwanan origin of the northern Myanmar amber lacewing paleofauna. The first finding of a deeply bifurcated forewing MP with two free branches in Babinskaiidae (viz., Paradoxoleon chenruii gen. et sp. nov.) highlights the morphological diversity of this extinct family. The phylogenetic positions of Araripenymphes burmanus sp. nov. and Paradoxoleon chenruii gen. et sp. nov. were recovered on the basis of a morphology-based phylogenetic analysis, and the monophyly of Cratosmylidae + Babinskaiidae was corroborated. Given the paraphyly of Cratosmylidae, its familial status is discussed