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‣ Perineural Invasion in Aggressive Skin Carcinomas of the Head and Neck

CERNEA, Claudio R.; FERRAZ, Alberto R.; CASTRO, Ines V. de; SOTTO, Miriam N.; LOGULLO, Angela F.; BACCHI, Carlos E.; PLOPPER, Caio; WANDERLEI, Felipe; CARLUCCI JR., Dorival de; HOJAIJ, Flavio C.
Fonte: KARGER Publicador: KARGER
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.665073%
Introduction: Perineural invasion is a well-recognized form of cancer dissemination. However, it has been reported only in few papers concerning cutaneous carcinomas ( basal cell, BCC, and squamous cell, SCC). Moreover, the incidence is considered to be very low. Niazi and Lambert [Br J Plast Surg 1993; 46: 156-157] reported only 0.18% of perineural invasion among 3,355 BCCs. It is associated with high-risk subtypes, as morphea-like, as well as with an increased risk of local recurrence. No paper was found in the literature looking for perineural invasion in very aggressive skin cancers with skull base extension, with immunohistochemical analysis. Methods: This is a retrospective review, including 35 very advanced skin carcinomas with skull base invasion (24 BCCs and 11 SCCs, operated on at a single institution from 1982 to 2000). Representative slides were immunohistochemically evaluated with antiprotein S-100, in order to enhance nerve fibers and to detect perineural invasion. The results were compared to 34 controls with tumors with a good outcome, treated in the same time frame at the same Institution. Results: Twelve (50.0%) of the BCCs with skull base invasion had proven perineural invasion, as opposed to only 1 (4.6%) of the controls...

‣ Laminin-derived peptide AG73 regulates migration, invasion, and protease activity of human oral squamous cell carcinoma cells through syndecan-1 and beta 1 integrin

SIQUEIRA, Adriane S.; GAMA-DE-SOUZA, Leticia N.; ARNAUD, Maria Vanda C.; PINHEIRO, Joao J. V.; JAEGER, Ruy G.
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.6048%
Squamous cell carcinoma is a prevalent head and neck tumor with high mortality. We studied the role played by laminin alpha 1 chain peptide AG73 on migration, invasion, and protease activity of cells (OSCC) from human oral squamous cell carcinoma. Immunohistochemistry and immunofluorescence analyzed expression of laminin alpha 1 chain and MMP9 in oral squamous cells carcinoma in vivo and in vitro. Migratory activity of AG73-treated OSCC cells was investigated by monolayer wound assays and in chemotaxis chambers. AG73-induced invasion was assessed in Boyden chambers. Invasion depends on MMPs. Conditioned media from cells grown on AG73 was subjected to zymography. We searched for AG73 receptors related to these activities in OSCC cells. Immunofluorescence analyzed AG73induced colocalization of syndecan-1 and beta 1 integrin. Cells had these receptors silenced by siRNA, followed by treatment with AG73 and analysis of migration, invasion, and protease activity. Oral squamous cell carcinoma expresses laminin alpha 1 chain and MMP9. OSCC cells treated with AG73 showed increased migration, invasion, and protease activity. AG73 induced colocalization of syndecan-1 and beta 1 integrin. Knockdown of these receptors decreased AG73-dependent migration...

‣ Ecologia e controle da invasão de Pinus elliottii no campo cerrado; Ecology of invasion and management of slash pine in a Brazilian savanna

Abreu, Rodolfo Cesar Real de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/05/2013 Português
Relevância na Pesquisa
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Os impactos negativos que as espécies invasoras causam aos ecossistemas naturais ou seminaturais são noticiados há pelo menos seis décadas em diferentes partes do mundo. Diversos estudos têm sido realizados visando diagnosticar o processo de invasão, conhecer a ecologia das espécies invasoras e gerar subsídios para o manejo, controle ou erradicação daquelas que causam problemas. No Brasil, a invasão de ecossistemas naturais começou a ser estudada recentemente e muito conhecimento ainda precisa ser gerado para basear a tomada de decisões sobre o problema. Este estudo teve por objetivo descrever o processo de invasão do Cerrado por Pinus elliottii e buscar técnicas de manejo viáveis ecológica e economicamente para o controle da invasora. O estudo foi realizado na Estação Ecológica de Santa Bárbara, no munícipio de Águas de Santa Bárbara, São Paulo, em duas frentes de pesquisa: uma para estudar a ecologia da espécie invasora, e a outra para verificar qual seria a técnica de controle mais vantajosa ecológica e economicamente. O estudo de ecologia baseou-se na amostragem de cinco blocos de 10 parcelas, cada uma com área de 10 x 10 m, para o estudo de plantas nativas com altura a partir de 50 cm e, dentro de cada parcela...

‣ Perineural Invasion in Aggressive Skin Carcinomas of the Head and Neck

Cernea, Claudio R.; Ferraz, Alberto R.; de Castro, Ines V.; Sotto, Miriam N.; Logullo, Angela F.; Bacchi, Carlos Eduardo; Plopper, Caio; Wanderlei, Felipe; de Carlucci, Dorival; Hojaij, Flavio C.
Fonte: Karger Publicador: Karger
Tipo: Artigo de Revista Científica Formato: 21-26
Português
Relevância na Pesquisa
36.653428%
Introduction: Perineural invasion is a well-recognized form of cancer dissemination. However, it has been reported only in few papers concerning cutaneous carcinomas ( basal cell, BCC, and squamous cell, SCC). Moreover, the incidence is considered to be very low. Niazi and Lambert [Br J Plast Surg 1993; 46: 156-157] reported only 0.18% of perineural invasion among 3,355 BCCs. It is associated with high-risk subtypes, as morphea-like, as well as with an increased risk of local recurrence. No paper was found in the literature looking for perineural invasion in very aggressive skin cancers with skull base extension, with immunohistochemical analysis. Methods: This is a retrospective review, including 35 very advanced skin carcinomas with skull base invasion (24 BCCs and 11 SCCs, operated on at a single institution from 1982 to 2000). Representative slides were immunohistochemically evaluated with antiprotein S-100, in order to enhance nerve fibers and to detect perineural invasion. The results were compared to 34 controls with tumors with a good outcome, treated in the same time frame at the same Institution. Results: Twelve (50.0%) of the BCCs with skull base invasion had proven perineural invasion, as opposed to only 1 (4.6%) of the controls...

‣ Adipose tissue-derived stem cells promote pancreatic cancer cell proliferation and invasion

Ji,S.Q.; Cao,J.; Zhang,Q.Y.; Li,Y.Y.; Yan,Y.Q.; Yu,F.X.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2013 Português
Relevância na Pesquisa
36.55261%
To explore the effects of adipose tissue-derived stem cells (ADSCs) on the proliferation and invasion of pancreatic cancer cells in vitro and the possible mechanism involved, ADSCs were cocultured with pancreatic cancer cells, and a cell counting kit (CCK-8) was used to detect the proliferation of pancreatic cancer cells. ELISA was used to determine the concentration of stromal cell-derived factor-1 (SDF-1) in the supernatants. RT-PCR was performed to detect the expression of the chemokine receptor CXCR4 in pancreatic cancer cells and ADSCs. An in vitro invasion assay was used to measure invasion of pancreatic cancer cells. SDF-1 was detected in the supernatants of ADSCs, but not in pancreatic cancer cells. Higher CXCR4 mRNA levels were detected in the pancreatic cancer cell lines compared with ADSCs (109.3±10.7 and 97.6±7.6 vs 18.3±1.7, respectively; P<0.01). In addition, conditioned medium from ADSCs promoted the proliferation and invasion of pancreatic cancer cells, and AMD3100, a CXCR4 antagonist, significantly downregulated these growth-promoting effects. We conclude that ADSCs can promote the proliferation and invasion of pancreatic cancer cells, which may involve the SDF-1/CXCR4 axis.

‣ Identification of genes regulating migration and invasion using a new model of metastatic prostate cancer

Banyard, Jacqueline; Chung, Ivy; Migliozzi, Matthew; Phan, Derek T; Wilson, Arianne M; Zetter, Bruce R; Bielenberg, Diane R
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.58154%
Background: Understanding the complex, multistep process of metastasis remains a major challenge in cancer research. Metastasis models can reveal insights in tumor development and progression and provide tools to test new intervention strategies. Methods: To develop a new cancer metastasis model, we used DU145 human prostate cancer cells and performed repeated rounds of orthotopic prostate injection and selection of subsequent lymph node metastases. Tumor growth, metastasis, cell migration and invasion were analyzed. Microarray analysis was used to identify cell migration- and cancer-related genes correlating with metastasis. Selected genes were silenced using siRNA, and their roles in cell migration and invasion were determined in transwell migration and Matrigel invasion assays. Results: Our in vivo cycling strategy created cell lines with dramatically increased tumorigenesis and increased ability to colonize lymph nodes (DU145LN1-LN4). Prostate tumor xenografts displayed increased vascularization, enlarged podoplanin-positive lymphatic vessels and invasive margins. Microarray analysis revealed gene expression profiles that correlated with metastatic potential. Using gene network analysis we selected 3 significantly upregulated cell movement and cancer related genes for further analysis: EPCAM (epithelial cell adhesion molecule)...

‣ Intracellular Signaling and Trafficking in Cancer: Role of Rab5-GTPase in Migration and Invasion of Breast Cells

Porther, Nicole
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
Relevância na Pesquisa
36.55261%
Metastasis is characterized pathologically by uncontrolled cell invasion, proliferation, migration and angiogenesis. Steroid hormones, such as estrogen, and growth factors, which include insulin growth factor I/II (IGF-1/IGF-2) therapy has been associated with most if not all of the features of metastasis. It has been determined that IGF-1 increases cell survival of cancer cells and potentiate the effect of E2 and other ligand growth factors on breast cancer cells. However not much information is available that comprehensively expounds on the roles of insulin growth factor receptor (IGFR) and Rab GTPases may play in breast cancer. The latter, Rab GTPases, are small signaling molecules and critical in the regulation of many cellular processes including cell migration, growth via the endocytic pathway. This research involves the role of Rab GTPases, specifically Rab5 and its guanine exchange factors (GEFs), in the promotion of cancer cell migration and invasion. Two important questions abound: Are IGFR stimulation and downstream effect involved the endocytic pathway in carcinogenesis? What role does Rab5 play in cell migration and invasion of cancer cells? The hypothesis is that growth factor signaling is dependent on Rab5 activity in mediating the aggressiveness of cancer cells. The goal is to demonstrate that IGF-1 signaling is dependent on Rab5 function in breast cancer progression. Here...

‣ Mutant p53 drives invasion in breast tumors through up-regulation of miR-155

Neilsen, P.; Noll, J.; Mattiske, S.; Bracken, C.; Gregory, P.; Schulz, R.; Lim, S.; Sharma, R.; Suetani, R.; Goodall, G.; Callen, D.
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Publicado em //2013 Português
Relevância na Pesquisa
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Loss of p53 function is a critical event during tumorigenesis, with half of all cancers harboring mutations within the TP53 gene. Such events frequently result in the expression of a mutated p53 protein with gain-of-function properties that drive invasion and metastasis. Here, we show that the expression of miR-155 was up-regulated by mutant p53 to drive invasion. The miR-155 host gene was directly repressed by p63, providing the molecular basis for mutant p53 to drive miR-155 expression. Significant overlap was observed between miR-155 targets and the molecular profile of mutant p53-expressing breast tumors in vivo. A search for cancer-related target genes of miR-155 revealed ZNF652, a novel zinc-finger transcriptional repressor. ZNF652 directly repressed key drivers of invasion and metastasis, such as TGFB1, TGFB2, TGFBR2, EGFR, SMAD2 and VIM. Furthermore, silencing of ZNF652 in epithelial cancer cell lines promoted invasion into matrigel. Importantly, loss of ZNF652 expression in primary breast tumors was significantly correlated with increased local invasion and defined a population of breast cancer patients with metastatic tumors. Collectively, these findings suggest that miR-155 targeted therapies may provide an attractive approach to treat mutant p53-expressing tumors.; PM Neilsen...

‣ Invasive fireweed in Australia: exploring the invasion dynamics of Senecio madagascariensis using population genetics.

Dormontt, Eleanor Elizabeth
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2013 Português
Relevância na Pesquisa
36.55261%
Senecio madagascariensis (fireweed) is an herbaceous flowering plant native to South Africa and known to be invasive in Australia, Argentina, Brazil, Hawaii and Japan. Fireweed first appeared in the Australian herbarium record in 1918 but little is known about its invasion dynamics. This thesis presents detailed molecular genetic analyses of S. madagascariensis in Australia and native South Africa, as well as broad biogeographic analysis of S. madagascariensis invasions from around the world. The thesis aims were to elucidate geographic source, mode of introduction, spread dynamics, hybridisation outcomes with an Australian congener, and potential for adaption to the Australian environment. Using nuclear and chloroplast microsatellites, populations from across the range in Australia and in the KwaZulu Natal province of South Africa were genotyped. Additionally, chloroplast microsatellites were used to genotype all S. madagascariensis specimens held in the Queensland Herbarium, National Herbarium of Victoria and National Herbarium of New South Wales, and from contemporary populations in all other known invasive ranges of the species across the world. Amplified fragment length polymorphisms (AFLPs) were used to study the outcome of hybridisation between S. madagascariensis and a S. pinnatifolius ‘dune variant’ in natural populations...

‣ New approaches to studying Plasmodium falciparum merozoite invasion and insights into invasion biology

Boyle, M.; Wilson, D.; Beeson, J.
Fonte: Pergamon-Elsevier Science Ltd Publicador: Pergamon-Elsevier Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2013 Português
Relevância na Pesquisa
36.6048%
Merozoite invasion of human red blood cells by Plasmodium falciparum is essential for blood stage asexual replication and the development of malaria disease. Despite this, many of the processes involved in invasion are poorly understood. Recent advances have been made in methods to isolate viable merozoites for studies of invasion. The application of these approaches is providing new insights into the kinetics of invasion and merozoite survival, as well as proteins and interactions involved in invasion, and will facilitate the development and testing of anti-merozoite vaccines and the identification of invasion-inhibitory compounds with potential for drug development. This review discusses these recent advances and considers potential avenues for future research.; Michelle J. Boyle, Danny W. Wilson, James G. Beeson

‣ Isolation of viable Plasmodium falciparum merozoites to define erythrocyte invasion events and advance vaccine and drug development

Boyle, M.; Wilson, D.; Richards, J.; Riglar, D.; Tetteh, K.; Conway, D.; Ralph, S.; Baum, J.; Beeson, J.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
Publicado em //2010 Português
Relevância na Pesquisa
36.653428%
During blood-stage infection by Plasmodium falciparum, merozoites invade RBCs. Currently there is limited knowledge of cellular and molecular invasion events, and no established assays are available to readily measure and quantify invasion-inhibitory antibodies or compounds for vaccine and drug studies. We report the isolation of viable merozoites that retain their invasive capacity, at high purity and yield, purified by filtration of highly synchronous populations of schizonts. We show that the half-life of merozoite invasive capacity after rupture is 5 min at 37 °C, and 15 min at room temperature. Studying the kinetics of invasion revealed that 80% of invasion events occur within 10 min of mixing merozoites and RBCs. Invasion efficiency was maximum at low merozoite-to-RBC ratios and occurred efficiently in the absence of serum and with high concentrations of dialyzed nonimmune serum. We developed and optimized an invasion assay by using purified merozoites that enabled invasion-inhibitory activity of antibodies and compounds to be measured separately from other mechanisms of growth inhibition; the assay was more sensitive for detecting inhibitory activity than established growth-inhibition assays. Furthermore, with the use of purified merozoites it was possible to capture and fix merozoites at different stages of invasion for visualization by immunofluorescence microscopy and EM. We thereby demonstrate that processing of the major merozoite antigen merozoite surface protein-1 occurs at the time of RBC invasion. These findings have important implications for defining invasion events and molecular interactions...

‣ Untersuchungen zur Funktion von Heparansulfat-Proteoglykanen während der Invasion von Neisseria gonorrhoeae in Epithelzellen; The role of heparansulfate-proteoglycans during the invasion of Neisseria gonorrhoeae into epithelial cells

Freissler, Elke
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
Relevância na Pesquisa
36.623904%
Neisseria gonorrhoeae (Ngo) adhäriert über das Opa50-Protein an nicht-polarisierte Epithelzellen. In der vorliegenden Arbeit wurde untersucht, ob die Adhärenz des Opa50-Proteins an Heparansulfat-Proteoglykane (HSPG) ausreicht, um eine Invasion von Ngo zu bewirken. Durch Kopplung von Latexbeads mit einem Antikörper gegen Heparansulfat-Glukosaminoglykane konnte über Immunfluoreszenzfärbungen nachgewiesen werden, daß die Beads von den Zellen aufgenommen werden. Die Phagozytose erfolgt mit der gleichen Kinetik wie die von Ngo. Für die Phagozytose der Beads ist eine Kreuzvernetzung der HSPGs sowie ein intaktes Zytoskelett. Die phagozytische Aufnahme der Beads wird durch Inhibitoren der Protein Kinase C (PKC) gehemmt und die Invasion der Beads wird durch die Zugabe von Vitronektin bzw. Serum gesteigert wie es für Ngo gezeigt wurde. Diese Daten weisen darauf hin, daß eine Kreuzvernetzung der HSPGs zu einer Phagozytose führen kann und daß das etablierte System ein gutes Modell für die Aufnahme von Ngo darstellt. Des weiteren führt die Überexpression von Syndekan-1 und Syndekan-4 in HeLa Zellen zu einer erhöhten Invasion von Ngo in diesen Zellinien. Deletionen der intrazellulären Domäne bewirken einen annähernd vollständigen Rückgang der Phagozytose von Ngo...

‣ ΔNp63α activates CD82 metastasis suppressor to inhibit cancer cell invasion

Wu, J; Liang, S; Bergholz, J; He, H; Walsh, E M; Zhang, Y; Xiao, Z-X
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.58154%
P63 is a p53 family member involved in multiple facets of biology, including embryonic development, cell proliferation, differentiation, survival, apoptosis, senescence and aging. The p63 gene encodes multiple protein isoforms either with (TAp63) or without (ΔNp63) the N-terminal transactivation domain. Amounting evidence suggests that p63 can function as a tumor suppressor, yet the precise molecular mechanisms, and particularly the specific roles of TAp63 and ΔNp63 in cancer progression, are still largely unclear. Here, we demonstrated that ΔNp63α, the predominant isoform expressed in epithelial cells and squamous cell carcinomas, inhibits cell invasion. Affymetrix gene expression profiling, combined with gain- and loss-of-function analyses and chromatin immunoprecipitation, indicated that cluster of differentiation 82 (CD82), a documented metastasis suppressor, is a direct transcriptional target of ΔNp63α. Expression of ΔNp63α inhibited outgrowth in Matrigel and cancer cell invasion, which was largely reversed by specific ablation of CD82. Conversely, ΔNp63α knockdown led to increased cell invasion, which was reversed by ectopic expression of CD82. Moreover, inhibition of glycogen synthase kinase-3β (GSK3β) by either pharmacological inhibitors or by RNA interference resulted in the downregulation of ΔNp63α and CD82 expression...

‣ Influence of Spartina alterniflora invasion stages on macrobenthic communities on a tidal flat in Wenzhou Bay, China

Ge,Bao-Ming; Bao,Yi-Xin; Cheng,Hong-Yi; Zhang,Dai-Zhen; Hu,Zhi-Yuan
Fonte: Universidade de São Paulo, Instituto Oceanográfico Publicador: Universidade de São Paulo, Instituto Oceanográfico
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2012 Português
Relevância na Pesquisa
36.69188%
Many coastal habitats in eastern China are being substantially altered by the invasion of Spartina alterniflora. The species richness, density, Margalef's diversity index (R) and Shannon's diversity index (H') of macrobenthic communities on a tidal flat in Wenzhou Bay, China, were analyzed with the factors of invasion stage and season, in 2007. A significant effect of invasion stage, season, and the interaction between them on communities was detected. The macrobenthic community was more complex in the patch of initial S. alterniflora invasion than in the patches of some other invasion stages. Macrobenthic communities were classified by cluster and ordination in accordance with the habitat character of the S. alterniflora invasion stage. Our research demonstrated that the S. alterniflora invasion stage affected the macrobenthic communities significantly. The results indicated that biodiversity increased in the initial stage of invasion (invasion age 1-2 years) and then decreased in the stage of invasion underway (invasion age 3-4 years) and in the stage of invasion completed (invasion age 5-6 years); this phenomenon was related to the change in the S. alterniflora canopy which accompanied the invasion stages.

‣ Acción del hexaclorobenceno en la migración, invasión y metástasis en modelos experimentales de cáncer de mama; Hexachlorobenene action on migration, invasion and metastasis in breast cancer experimental models

Pontillo, Carolina Andrea
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2012 Português
Relevância na Pesquisa
36.675186%
El Hexaclorobenceno (HCB) es un pesticida organoclorado considerado como probable carcinógeno humano. A nivel regional, este contaminante fue encontrado en leche materna de puérperas y en muestras de leche vacuna para consumo humano. Es un tóxico tipo dioxina, y como tal se une al receptor de hidrocarburos aromáticos (RHA), un factor de transcripción que modula procesos tales como apoptosis, proliferación y migración celular. El RHA está presente en el citosol e interacciona con el complejo que contiene a la quinasa de tirosina c-Src. Cuando estos tóxicos se unen al RHA, se pueden desencadenar dos mecanismos: 1) que el complejo tóxico-RHA se transloque al núcleo y module la expresión de genes con elementos de respuesta a dioxinas (DREs) en sus promotores y 2) que se libere la c-Src del complejo citosólico y active receptores de factores de crecimiento, como el Receptor de Factor de Crecimiento Epidérmico (HER1). Resultados previos de nuestro laboratorio demostraron que el HCB aumenta el desarrollo y malignidad de tumores mamarios inducidos por N-Nitroso-N-metilurea en rata. En este mismo modelo se observó que el HCB activa la vía de señalización de c-Src/HER1 y disminuye la actividad del receptor de estrógenos (REα) en los tumores mamarios. Por otro lado...

‣ Acción del hexaclorobenceno en la migración, invasión y metástasis en modelos experimentales de cáncer de mama; Hexachlorobenene action on migration, invasion and metastasis in breast cancer experimental models

Pontillo, Carolina Andrea
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: Tesis Doctoral Formato: text; pdf
Publicado em //2012 Português
Relevância na Pesquisa
36.58154%
El Hexaclorobenceno (HCB) es un pesticida organoclorado considerado como probable carcinógeno humano. A nivel regional, este contaminante fue encontrado en leche materna de puérperas y en muestras de leche vacuna para consumo humano. Es un tóxico tipo dioxina, y como tal se une al receptor de hidrocarburos aromáticos (RHA), un factor de transcripción que modula procesos tales como apoptosis, proliferación y migración celular. El RHA está presente en el citosol e interacciona con el complejo que contiene a la quinasa de tirosina c-Src. Cuando estos tóxicos se unen al RHA, se pueden desencadenar dos mecanismos: 1) que el complejo tóxico-RHA se transloque al núcleo y module la expresión de genes con elementos de respuesta a dioxinas (DREs) en sus promotores y 2) que se libere la c-Src del complejo citosólico y active receptores de factores de crecimiento, como el Receptor de Factor de Crecimiento Epidérmico (HER1). Resultados previos de nuestro laboratorio demostraron que el HCB aumenta el desarrollo y malignidad de tumores mamarios inducidos por N-Nitroso-N-metilurea en rata. En este mismo modelo se observó que el HCB activa la vía de señalización de c-Src/HER1 y disminuye la actividad del receptor de estrógenos (REα) en los tumores mamarios. Por otro lado...

‣ Influence of Spartina alterniflora invasion stages on macrobenthic communities on a tidal flat in Wenzhou Bay, China

Ge, Bao-Ming; Bao, Yi-Xin; Cheng, Hong-Yi; Zhang, Dai-Zhen; Hu, Zhi-Yuan
Fonte: Universidade de São Paulo. Instituto Oceanográfico Publicador: Universidade de São Paulo. Instituto Oceanográfico
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 01/01/2012 Português
Relevância na Pesquisa
36.69188%
Many coastal habitats in eastern China are being substantially altered by the invasion of Spartina alterniflora. The species richness, density, Margalef's diversity index (R) and Shannon's diversity index (H') of macrobenthic communities on a tidal flat in Wenzhou Bay, China, were analyzed with the factors of invasion stage and season, in 2007. A significant effect of invasion stage, season, and the interaction between them on communities was detected. The macrobenthic community was more complex in the patch of initial S. alterniflora invasion than in the patches of some other invasion stages. Macrobenthic communities were classified by cluster and ordination in accordance with the habitat character of the S. alterniflora invasion stage. Our research demonstrated that the S. alterniflora invasion stage affected the macrobenthic communities significantly. The results indicated that biodiversity increased in the initial stage of invasion (invasion age 1-2 years) and then decreased in the stage of invasion underway (invasion age 3-4 years) and in the stage of invasion completed (invasion age 5-6 years); this phenomenon was related to the change in the S. alterniflora canopy which accompanied the invasion stages.; Muitos habitats costeiros vêm sendo alterados substancialmente pela invasão de Spartina alterniflora no leste da China. Em 2007...

‣ Basement  Membrane  Dynamics  During  Anchor  Cell  Invasion

Morrissey, Meghan Ann
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação
Publicado em //2015 Português
Relevância na Pesquisa
36.623904%

Basement membranes are a dense, sheet-like form of extracellular matrix that underlie epithelia and endothelia, and surround muscle, fat and Schwann cells. Basement membranes separate tissues and protect them from mechanical stresses. Although traditionally thought of as a static support structure, a growing body of evidence suggests that dynamic basement membrane deposition and modification instruct cell behavior and morphogenetic processes. In this thesis, I discuss how changes to basement membrane affect anchor cell (AC) invasion during C. elegans uterine vulval attachment. During AC invasion, the uterine AC breaches two juxtaposed basement membranes to contact the underlying vulval epithelium. Using live-cell imaging, genetics, molecular biology and electron microscopy I identify three modifications to the BM that affect AC invasion. In Chapter 2, I describe a system for linking juxtaposed basement membranes to stably align or connect adjacent tissues. This adhesion system promotes rapid AC invasion and also regulates a more long-term connection between the uterine tissue and the hypodermal seam cell in the adult worm. Chapter 3 elucidates how the BM component SPARC promotes cell invasion. As SPARC overexpression is correlated with cancer metastasis...

‣ El papel pronóstico de la invasión perineural en la biopsia prostática

Gutiérrez,C.; Terrasa,F.; Briones,G.; Conde,G.; Fuentes,I.; Hidalgo,F.; Bestard,J.; Rebassa,M.
Fonte: Actas Urológicas Españolas Publicador: Actas Urológicas Españolas
Tipo: info:eu-repo/semantics/article; journal article; info:eu-repo/semantics/publishedVersion Formato: text/html; application/pdf
Publicado em 01/06/2011 Português
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Introducción: A pesar de que la diseminación celular tumoral a través del sistema nervioso intraprostático se considera un mecanismo de progresión del cáncer prostático, el significado de la invasión perineural en biopsias de próstata para predecir extensión extraprostática y su utilidad como potencial factor pronóstico es controvertido. Material y métodos: Estudio retrospectivo llevado a cabo en una institución sobre 208 pacientes tratados con prostatectomía radical (enero 2007-julio 2010) en los que se ha determinado la presencia de invasión perineural y el score de gleason en la biopsia preoperatoria, así como el estadio clínico y el PSA prequirúrgico. Clasificamos los pacientes en grupos de riesgo según la clasificación de D'Amico. Realizamos análisis estadístico bivariante y multivariante para establecer la correlación entre las distintas variables. Resultados: Se objetivó IPN en el 18,3% de las biopsias prostáticas. Presentaron extensión extraprostática el 71% de los espécimenes de prostatectomía con invasión perineural en la biopsia previa vs. 23,1% cuando no existía este hallazgo (p<0,0001) y márgenes positivos el 47,4% de los casos con IPN, frente a 18,3% sin invasión perineural (p<0,0001). De hecho...

‣ Identifying areas of high invasion risk: a general model and an application to Mexico

del-Val,Ek; Balvanera,Patricia; Castellarini,Fabiana; Espinosa-García,Francisco Javier; Murguía,Miguel; Pacheco,Carlos
Fonte: Instituto de Biología Publicador: Instituto de Biología
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2015 Português
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Maps have become a key tool to guide priorities for biodiversity conservation, the maintenance of ecosystem services, but much less so for critical action against further service loss in critical areas. Biological invasions are important disruptors of ecosystem services given that they directly or indirectly affect human well being, as they are an important cause of biodiversity loss worldwide and interfere with the provision of many ecosystem services. Here, we propose a general model to identify regions where the probability of plant invasion is higher and can cause and/or aggravate negative effects upon ecosystems. We then apply the general model to Mexico. Our model of probability of invasion considers 4 main variables: propagule availability, vegetation type, anthropic disturbance and native plant species richness. We calculated an invasion risk index combining all factors. We produced 5 maps, one for each variable and another constructed with our model of combined risk, for a grid of 0.5º × 0.5º grid across the whole country. We validated our model with State level data on exotic plants per State and obtained a significant correlation (r= 0.73, p< 0.001) between our invasion risk index derived from the model and the observed density of exotic species. Areas with greater susceptibility to invasion are closer to large human settlements and to areas of intensive agriculture. Very high risk corridors and islands were detected in our maps...