Differentiation of the Yolk Sac of the Chick Studied by Electron Microscopy

Development ◽  
1963 ◽  
Vol 11 (1) ◽  
pp. 201-225
Author(s):  
Ruth Bellairs
Keyword(s):  
Electron Microscopy ◽  
Chick Embryo ◽  
Yolk Sac ◽  
The Third ◽  
Striking Increase ◽  
And Migration ◽  
The Relationship ◽  
Proliferation And Migration

The chick embryo is nourished on yolk throughout its entire pre-natal life, the yolk sac being the organ responsible for the uptake of yolk and its digestion. This organ is formed from the area opaca, and during the first few days of incubation there is a striking increase in its area; in fact, the whole yolk becomes almost entirely covered by the end of the third day. This expansion is apparently the result of both proliferation and migration. It is generally considered that proliferation takes place largely in a band of tissue lying just proximal to the edge of the blastoderm (the so-called ‘syncytial’ zone or area vitellina externa). Migration has been shown to be due to the activity of highly specialized cells at the periphery (New, 1959). The purpose of Part I of this investigation was to study the relationship between the ‘syncytial’ zone and the underlying yolk, and to provide a description of the edge cells.

GNG5 is a novel oncogene associated with cell migration, proliferation, and poor prognosis in glioma

2021 ◽  
Author(s):  
Wang Zhang ◽  
Zhendong Liu ◽  
Binchao Liu ◽  
Miaomiao Jiang ◽  
Shi Yan ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Clinical Data ◽  
Poor Prognosis ◽  
Glioma Cells ◽  
Diagnosis And Treatment ◽  
And Migration ◽  
The Relationship ◽  
Proliferation And Migration

Abstract Background: Although many biomarkers have been reported for detecting glioma, the prognosis for the disease remains poor, and therefore, new biomarkers need to be identified. GNG5, which is part of the G-protein family, has been associated with different malignant tumors, though the role of GNG5 in glioma has not been studied. Therefore, we aimed to identify the relationship between GNG5 and glioma prognosis and identify a new biomarker for the diagnosis and treatment of gliomas.Methods: We used data on more than a thousand gliomas from multiple databases and clinical data to determine the expression of GNG5 in glioma. Based on clinical data and CGGA database, we identified the correlation between GNG5 and multiple molecular and clinical features and prognosis using various analytical methods. Co-expression analysis and GSEA were performed to detect GNG5-related genes in glioma and possible signaling pathways involved. ESTIMATE, ssGSEA, and TIMER were used to detect the relationship between GNG5 and the immune microenvironment. Functional experiments were performed to explore the function of GNG5 in glioma cells.Results: GNG5 is highly expressed in gliomas, and its expression level is positively correlated with pathological grade, histological type, age, and tumor recurrence and negatively correlated with isocitrate dehydrogenase mutation, 1p/19 co-deletion, and chemotherapy. Moreover, GNG5 as an independent risk factor was negatively correlated with the overall survival time. GSEA revealed the potential signaling pathways involved in GNG5 function in gliomas, including cell adhesion molecules signaling pathway. The ssGSEA, ESTIMATE, and TIMER based analysis indicated a correlation between GNG5 expression and various immune cells in glioma. In vivo and in vitro experiments showed that GNG5 could participate in glioma cell proliferation and migration.Conclusions: Based on the large data platform and the use of different databases to corroborate results obtained using various datasets, as well as in vitro and in vivo experiments, our study reveals for the first time that GNG5, as an oncogene, is overexpressed in gliomas and can inhibit the proliferation and migration of glioma cells and lead to poor prognosis of patients. Thus, GNG5 is a potential novel biomarker for the clinical diagnosis and treatment of gliomas.

scholarly journals In Vitro Effect of Modified Polyetheretherketone (PEEK) Implant Abutments on Human Gingival Epithelial Keratinocytes Migration and Proliferation

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1401 ◽  
Author(s):  
Liza L. Ramenzoni ◽  
Thomas Attin ◽  
Patrick R. Schmidlin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Tetrazolium Salt ◽  
Microscopy Imaging ◽  
Implant Abutments ◽  
And Migration ◽  
Vitro Effect ◽  
Scanning Electron ◽  
Proliferation And Migration

Improving soft tissue attachment to implant abutments is a crucial factor for enduring health and maintenance of soft peri-implant tissue health. In this in vitro study we aimed to compare the biocompatibility of three different abutment surfaces: titanium, zirconia and modified polyetheretherketone (PEEK). Surface topography, roughness and wettability were investigated with scanning electron microscopy, profilometer and contact angle meter, respectively. Human gingival epithelial keratinocytes were examined for viability, morphology, proliferation and migration by using tetrazolium salt colorimetric assay, scanning electron microscopy imaging, immunofluorescence bromodeoxyuridine analysis and scratch wound healing assays. Roughness measurements revealed differences between the investigated surfaces. Keratinocytes cultured on all examined surfaces indicated adhesion and attachment by means of scanning electron microscopy imaging. Cell viability assays showed no significant differences between the groups (p > 0.05). The modified PEEK surface similarly improved surface roughness in comparison to titanium and zirconia, which resulted in greater and equivalent cell proliferation and migration. The study methodology showed here may emphasize the importance of cell interactions with different abutment materials, which in part increases the changes of implant success. PEEK, titanium and zirconia surface types used in this study showed mostly similar epithelial biological responses.

scholarly journals MiR-520b/e Regulates Proliferation and Migration by Simultaneously Targeting EGFR in Gastric Cancer

2016 ◽  
Vol 40 (6) ◽  
pp. 1303-1315 ◽  
Author(s):  
Shuang Li ◽  
Haiyang Zhang ◽  
Tao Ning ◽  
Xinyi Wang ◽  
Rui Liu ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Cell Proliferation ◽  
Tumor Suppressor ◽  
Cell Lines ◽  
Growth Factor Receptor ◽  
Over Expression ◽  
Epidermal Growth ◽  
And Migration ◽  
The Relationship ◽  
Proliferation And Migration

Background: MicroRNAs (miRNAs) have been demonstrated to play a crucial role in tumorigenesis. Previous studies have shown that miR-520b/e acts as a tumor suppressor in several tumors. Other studies indicated that epidermal growth factor receptor (EGFR) is highly expressed in many tumors, and involved in the development of tumors, such as cell proliferation, migration, angiogenesis and apoptosis. However, the correlation of miRNAs and EGFR in gastric cancer (GC) has not been adequately investigated. Our aim was to explore the relationship. Methods: The expression levels of EGFR and miR-520b/e were examined by RT-PCR and Western blot. We also investigated the relationship between EGFR and miR-520b/e in GC cell lines by relevant experiments. Results: In this study, we found that miR-520b/e inhibits the protein expression of EGFR by directly binding with the 3'-untranslated region (3'-UTR). And it was shown that the down-regulation of miR-520b/e promotes cell proliferation and migration by negative regulation of the EGFR pathway, while over-expression of miR-520b/e inhibits these properties. In addition, the biological function of EGFR in GC cell lines was validated by silencing and over-expression assays respectively. Conclusions: Taken together, our results demonstrate that miR-520b/e acts as a tumor suppressor by regulating EGFR in GC, and provide a novel marker and insight for the potential therapeutic target of GC.

scholarly journals “Migration and Violence: Lessons from Colombia for the Americas” A workshop of the Transatlantic Forum on Migration and Integration and the Refugee Research Network (TFMI)

Refuge ◽  
2013 ◽  
Vol 29 (1) ◽  
pp. 131-136 ◽  
Author(s):  
Jorge Salcedo
Keyword(s):  
El Salvador ◽  
Central America ◽  
Academic Research ◽  
Lessons Learned ◽  
Research Network ◽  
Fourth Section ◽  
The Third ◽  
Similarities And Differences ◽  
And Migration ◽  
The Relationship

The conference, “Migration and Violence: Lessons from Colombia to the Americas” was held in Bogotá D.C., Colombia at the Pontifi cia Universidad Javeriana on June 29, 2012. The main objective of the conference was to develop inter-disciplinary academic research in Central America and Mexico regarding the relationship between violence, particularly narco-violence, and migration. The setting in Bogotá D.C. was deliberate as the participants discussed how lessons learned from Colombia’s experience with narco-induced migration could be leveraged for the benefit of Central America and Mexico. With the participation of experts on international migration, government representatives, academics, and civil society, the conference highlighted research results and relevant intervention experience concerning this problem in Colombia, El Salvador, Guatemala, and Mexico.This article presents an analysis of the presentations given and the discussions held at the conference. It consists of four parts. The first section compares the similarities and differences regarding migration and violence in Colombia and El Salvador, Guatemala, and Mexico. The second section presents the major epistemological challenges emerging from research and models of intervention. The third section presents the implications of the epistemological challenges and their impact on public policy. The fourth section concludes with principal lessons from Colombia for research and intervention in the problem of violence and migration.

scholarly journals DSG2 expression is correlated with poor prognosis and promotes early-stage cervical cancer

2020 ◽  
Author(s):  
Shuhang Qin ◽  
Yuandong Liao ◽  
Qiqiao Du ◽  
Wei Wang ◽  
Jiaming Huang ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Clinical Features ◽  
Poor Prognosis ◽  
Early Stage ◽  
Positive Regulation ◽  
Qrt Pcr ◽  
And Migration ◽  
Cox Analysis ◽  
The Relationship ◽  
Proliferation And Migration

Abstract Background: The pathogenesis and developmental mechanism of early-stage (FIGO 2009 IA2-IIA2) cervical cancer (CC) remain unclear. Seeking novel molecular biomarkers based on The Cancer Genome Atlas (TCGA) will facilitate the understanding of CC pathogenesis and help evaluate early-stage CC prognosis.Methods: To identify prognosis-related genes in early-stage CC, we analyzed TCGA mRNA-seq data and clinical data by univariate Cox and Kaplan-Meier plotter analyses. Differential expression analysis identified upregulated genes in early-stage CC. Combined with the genes correlated with unfavorable prognosis, we selected DSG2 for further investigation. To detect DSG2 expression in early-stage CC, we used immunohistochemistry (IHC), quantitative real-time PCR (qRT-PCR) and western blotting. The relationship between the expression of DSG2 and clinical features was analyzed by the chi-square test. Cox analysis was applied to assess the relationship between CC overall survival (OS) and risk factors. The correlations between DSG2 expression and CC cell line proliferation and migration were investigated with Cell Counting Kit-8 (CCK-8) and migration assays.Results: There were 416 prognosis-related genes in early-stage CC. DSG2, MMP1, CA9, HOXA1, and SERPINB3 were upregulated in early-stage CC compared with adjacent noncancerous tissue (ANT) and correlated with unfavorable prognosis. Among them, DSG2 was most significantly correlated with patient survival. Coexpression analysis indicated that DSG2 was probably involved in cell division, positive regulation of transferase activity, positive regulation of cell migration, EGFR upregulation pathway and regulation of lymphangiogenesis. IHC, qRT-PCR and western blotting showed that DSG2 expression was higher in CC than in normal tissue. Significant correlations were identified between DSG2 expression and several aggressive clinical features, including pelvic lymph node metastasis (PLNM). Multivariate Cox analysis showed that DSG2 and PLNM were independent prognostic factors for OS. DSG2 knockdown inhibited CC cell proliferation and migration.Conclusions: DSG2 is a new biomarker that promotes tumor proliferation and metastasis and is correlated with poor prognosis in early-stage CC.

scholarly journals Ras, PI3K and mTORC2 – three's a crowd?

2020 ◽  
Vol 133 (19) ◽  
pp. jcs234930
Author(s):  
Stephen F. Smith ◽  
Shannon E. Collins ◽  
Pascale G. Charest
Keyword(s):  
Ras Signaling ◽  
Cell Type ◽  
Cellular Processes ◽  
Mechanistic Target Of Rapamycin ◽  
Evolutionarily Conserved ◽  
Intracellular Compartments ◽  
Ras Effectors ◽  
And Migration ◽  
The Relationship ◽  
Proliferation And Migration

ABSTRACTThe Ras oncogene is notoriously difficult to target with specific therapeutics. Consequently, there is interest to better understand the Ras signaling pathways to identify potential targetable effectors. Recently, the mechanistic target of rapamycin complex 2 (mTORC2) was identified as an evolutionarily conserved Ras effector. mTORC2 regulates essential cellular processes, including metabolism, survival, growth, proliferation and migration. Moreover, increasing evidence implicate mTORC2 in oncogenesis. Little is known about the regulation of mTORC2 activity, but proposed mechanisms include a role for phosphatidylinositol (3,4,5)-trisphosphate – which is produced by class I phosphatidylinositol 3-kinases (PI3Ks), well-characterized Ras effectors. Therefore, the relationship between Ras, PI3K and mTORC2, in both normal physiology and cancer is unclear; moreover, seemingly conflicting observations have been reported. Here, we review the evidence on potential links between Ras, PI3K and mTORC2. Interestingly, data suggest that Ras and PI3K are both direct regulators of mTORC2 but that they act on distinct pools of mTORC2: Ras activates mTORC2 at the plasma membrane, whereas PI3K activates mTORC2 at intracellular compartments. Consequently, we propose a model to explain how Ras and PI3K can differentially regulate mTORC2, and highlight the diversity in the mechanisms of mTORC2 regulation, which appear to be determined by the stimulus, cell type, and the molecularly and spatially distinct mTORC2 pools.

scholarly journals GNG5 is a novel oncogene associated with cell migration, proliferation, and poor prognosis in glioma

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Wang Zhang ◽  
Zhendong Liu ◽  
Binchao Liu ◽  
Miaomiao Jiang ◽  
Shi Yan ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Clinical Data ◽  
Poor Prognosis ◽  
Glioma Cells ◽  
Diagnosis And Treatment ◽  
And Migration ◽  
The Relationship ◽  
Proliferation And Migration

Abstract Background Although many biomarkers have been reported for detecting glioma, the prognosis for the disease remains poor, and therefore, new biomarkers need to be identified. GNG5, which is part of the G-protein family, has been associated with different malignant tumors, though the role of GNG5 in glioma has not been studied. Therefore, we aimed to identify the relationship between GNG5 and glioma prognosis and identify a new biomarker for the diagnosis and treatment of gliomas. Methods We used data on more than a thousand gliomas from multiple databases and clinical data to determine the expression of GNG5 in glioma. Based on clinical data and CGGA database, we identified the correlation between GNG5 and multiple molecular and clinical features and prognosis using various analytical methods. Co-expression analysis and GSEA were performed to detect GNG5-related genes in glioma and possible signaling pathways involved. ESTIMATE, ssGSEA, and TIMER were used to detect the relationship between GNG5 and the immune microenvironment. Functional experiments were performed to explore the function of GNG5 in glioma cells. Results GNG5 is highly expressed in gliomas, and its expression level is positively correlated with pathological grade, histological type, age, and tumor recurrence and negatively correlated with isocitrate dehydrogenase mutation, 1p/19 co-deletion, and chemotherapy. Moreover, GNG5 as an independent risk factor was negatively correlated with the overall survival time. GSEA revealed the potential signaling pathways involved in GNG5 function in gliomas, including cell adhesion molecules signaling pathway. The ssGSEA, ESTIMATE, and TIMER based analysis indicated a correlation between GNG5 expression and various immune cells in glioma. In vivo and in vitro experiments showed that GNG5 could participate in glioma cell proliferation and migration. Conclusions Based on the large data platform and the use of different databases to corroborate results obtained using various datasets, as well as in vitro and in vivo experiments, our study reveals for the first time that GNG5, as an oncogene, is overexpressed in gliomas and can inhibit the proliferation and migration of glioma cells and lead to poor prognosis of patients. Thus, GNG5 is a potential novel biomarker for the clinical diagnosis and treatment of gliomas.

scholarly journals DSG2 expression is correlated with poor prognosis and promotes early-stage cervical cancer

2020 ◽  
Author(s):  
Shuhang Qin ◽  
Yuandong Liao ◽  
Qiqiao Du ◽  
Wei Wang ◽  
Jiaming Huang ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Clinical Features ◽  
Poor Prognosis ◽  
Early Stage ◽  
Positive Regulation ◽  
Qrt Pcr ◽  
And Migration ◽  
Cox Analysis ◽  
The Relationship ◽  
Proliferation And Migration

Abstract Background: The pathogenesis and developmental mechanism of early-stage (FIGO 2009 IA2-IIA2) cervical cancer (CC) remain unclear. Seeking novel molecular biomarkers based on The Cancer Genome Atlas (TCGA) will facilitate the understanding of CC pathogenesis and help evaluate early-stage CC prognosis. Methods: To identify prognosis-related genes in early-stage CC, we analyzed TCGA mRNA-seq data and clinical data by univariate Cox and Kaplan-Meier plotter analyses. Differential expression analysis identified upregulated genes in early-stage CC. Combined with the genes correlated with unfavorable prognosis, we selected DSG2 for further investigation. To detect DSG2 expression in early-stage CC, we used immunohistochemistry (IHC), quantitative real-time PCR (qRT-PCR) and western blotting. The relationship between the expression of DSG2 and clinical features was analyzed by the chi-square test. Cox analysis was applied to assess the relationship between CC overall survival (OS) and risk factors. The correlations between DSG2 expression and CC cell line proliferation and migration were investigated with Cell Counting Kit-8 (CCK-8) and migration assays. Results: There were 416 prognosis-related genes in early-stage CC. DSG2, MMP1, CA9, HOXA1, and SERPINB3 were upregulated in early-stage CC compared with adjacent noncancerous tissue (ANT) and correlated with unfavorable prognosis. Among them, DSG2 was most significantly correlated with patient survival. Coexpression analysis indicated that DSG2 was probably involved in cell division, positive regulation of transferase activity, positive regulation of cell migration, EGFR upregulation pathway and regulation of lymphangiogenesis. IHC, qRT-PCR and western blotting showed that DSG2 expression was higher in CC than in normal tissue. Significant correlations were identified between DSG2 expression and several aggressive clinical features, including pelvic lymph node metastasis (PLNM). Multivariate Cox analysis showed that DSG2 and PLNM were independent prognostic factors for OS. DSG2 knockdown inhibited CC cell proliferation and migration. Conclusions: DSG2 is a new biomarker that promotes tumor proliferation and metastasis and is correlated with poor prognosis in early-stage CC.

scholarly journals Sustained Release of IGF-1 by 3D Mesoporous Scaffolds Promoting Cardiac Stem Cell Migration and Proliferation

2018 ◽  
Vol 49 (6) ◽  
pp. 2358-2370 ◽  
Author(s):  
Yuning Sun ◽  
Xiqiong Han ◽  
Xin Wang ◽  
Boqian Zhu ◽  
Bing Li ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Cell Proliferation ◽  
Growth Factor ◽  
Sustained Release ◽  
Heart Function ◽  
Cell Scaffolds ◽  
Cell Scaffold ◽  
And Migration ◽  
Mesoporous Structures ◽  
Proliferation And Migration

Background/Aims: C-kit-positive cardiac stem cells (CSCs) may have potential as a treatment for cardiovascular disease. However, the low survival rates of c-kit-positive CSCs present a major challenge during the transplantation process. Methods: The hierarchical structure of the 3D cell scaffold was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and N2 adsorption-desorption isotherms. Analyses of the proliferation and migration performances of the IGF-1 scaffold on c-kit-positive CSCs were conducted by experiments including QuantiT PicoGreen dsDNA and transwell assays. Results: In this study, we synthesized for the first time a novel hierarchical macro-mesoporous silica material (denoted MS15-c) in a one-pot procedure for the release of insulin-like growth factor-1 (IGF-1) and a three-dimensional (3D) cell scaffold. Both macropores and mesopores were visible in MS15-c and enabled the sustained release of IGF-1, extending its half-life and enhancing CSC proliferation and migration. Proliferation and migration were detected by QuantiT PicoGreen dsDNA and transwell assays, respectively. Moreover, an in vivo experiment was conducted to detect heart function with the addition of MS15-c. The new strategy proposed in this paper may extend the bio-applications of 3D cell scaffolds, thus permitting the sustained release of growth factors and efficient promotion of cell proliferation. Conclusion: This work successfully demonstrated an effective strategy for the construction of MS15-c cell scaffolds with hierarchical macro-mesoporous structures. The macro-mesoporous structures gave cell scaffolds the ability to release a growth factor to facilitate cell growth, while the scaffold structure promoted cell proliferation.

scholarly journals Structural and microvascular study of soleous muscle of Wistar rats after section of the sciatic nerve

2004 ◽  
Vol 62 (3b) ◽  
pp. 835-838 ◽  
Author(s):  
Ana Cristina Camillo ◽  
Rodrigo de Carvalho Rocha ◽  
Renato Paulo Chopard
Keyword(s):  
Electron Microscopy ◽  
Skeletal Muscle ◽  
Satellite Cells ◽  
Wistar Rats ◽  
Capillary Density ◽  
Regenerative Process ◽  
Transmission Electron ◽  
Skeletal Muscle Microcirculation ◽  
And Migration ◽  
The Relationship

It is not well established yet the relationship between the activation of satellite cells and skeletal muscle microcirculation after surgical denervation. Trough scanning and transmission electron microscopy methods, we studied comparatively the alterations of the soleus muscle in Wistar rats after surgical denervation. Our results evidenced the activation, duplication and migration of satellite cells to the interior of muscle fibers coexisting with a raise in the capillary density characterized by a higher number of anastomosis and capillary sprouts. We conclude that the microcirculation plays a key role in the regenerative process.

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