166 research outputs found

    SOCIAL, ECONOMIC AND CULTURAL DIAGNOSIS OF THE ARTISANAL FISHERMEN COMMUNITIES OF THE CENTER-NORTH SANTA CATARINA COASTAL ZONE.

    Get PDF
    A pesca artesanal é uma atividade tradicional na Zona Costeira do Estado de Santa Catarina, exercendo um importante papel histórico, social e econômico nesta região. Este estudo foi realizado no litoral Centro-Norte do Estado de Santa Catarina, incluindo 10 municípios: Barra Velha, Piçarras, Penha, Navegantes, ltajaí, Balneário Camboriú, Itapema, Porto Belo, Bombinhas e Tijucas, onde um diagnóstico e planejamento ambiental foi produzido. Para realizar este diagnóstico, foram realizadas 482 entrevistas com pescadores artesanais. Os resultados indicaram que a pesca de arrasto de camarão é a principal atividade pesqueira artesanal da área. Verificou-se também que, em geral, a pesca artesanal apresenta problemas importantes como a falta de fiscalização da atuação da frota industrial próxima à costa e a falta de uma política de apoio à pesca artesanal. Um outro sério problema é o desenvolvimento desordenado da orla marítima, anti¬gamente dominada por comunidades pesqueiras. Isto resultou numa diminuição do número de pescadores na comunidade e uma diminuição da rentabilidade da pesca. Soluções imediatas, como por exemplo, programas de extensão universitária, educação ambiental e uma reavaliação da política pesqueira devem ser realizadas antes que esta atividade desapareça do litoral Centro-Norte do Estado de Santa Catarina.The artisanal fishery is a traditional activity in the coastal Zone of Santa Catarina State, playing an important historical-social and economic role in this region. This study was conducted in the central and Northern part of Santa Catarina coastal zone, which included ten municipalities: Barra Velha, Piçarras, Penha, Navegantes, Itajaí, Balneário Camboriú, Itapema, Porto Belo, Bombinhas and Tijucas. A diagnosis of artisanal fishery in this area was achieved through 482 questionnairy interviews with fishermen and their families. The results indicated that artisanal shrimp fishery is the main activity in this area. It was also verified that the artisanal fisheries as a whole has serious problems such as the lack of fiscalization of the industrial fleet near the coastline, and 'he lack of supporting policies for these fishery sector. Another serious problem is the non planned urbanisation in the beaches formely dominated by fishermen settlement. As a result, it was verified a decrease of the number of fishermen and a decrease in the economical benefits of the artisanal fishing activity. lmmediate solutions, such as universitary extension programs such as environmental education and revaluation of the fishery policies must be taken before this culturally and historically important activity disappears from Center North Santa Catarina coastal zone

    Soluble factors regulated by epithelial-mesenchymal transition mediate tumour angiogenesis and myeloid cell recruitment.

    Full text link
    peer reviewedEpithelial-to-mesenchymal transition (EMT) programs provide cancer cells with invasive and survival capacities that might favor metastatic dissemination. Whilst signaling cascades triggering EMT have been extensively studied, the impact of EMT on the crosstalk between tumor cells and the tumor microenvironment remains elusive. We aimed to identify EMT-regulated soluble factors that facilitate the recruitment of host cells in the tumor. Our findings indicate that EMT phenotypes relate to the induction of a panel of secreted mediators, namely IL-8, IL-6, sICAM-1, PAI-1 and GM-CSF, and implicate the EMT-transcription factor Snail as a regulator of this process. We further show that EMT-derived soluble factors are pro-angiogenic in vivo (in the mouse ear sponge assay), ex vivo (in the rat aortic ring assay) and in vitro (in a chemotaxis assay). Additionally, conditioned medium from EMT-positive cells stimulates the recruitment of myeloid cells. In a bank of 40 triple-negative breast cancers, tumors presenting features of EMT were significantly more angiogenic and infiltrated by a higher quantity of myeloid cells compared to tumors with little or no EMT. Taken together, our results show that EMT programs trigger the expression of soluble mediators in cancer cells that stimulate angiogenesis and recruit myeloid cells in vivo, which might in turn favor cancer spread

    On the theory of tumor self-seeding: implications for metastasis progression in humans

    Get PDF
    Metastasis remains the leading cause of death among cancer patients because few effective treatment options are available. A recent paper proposes a new twist on metastasis. The paper shows that circulating tumor cells can return to the primary tumor, a process termed tumor self-seeding or cross-seeding, and that this helps breeding tumor cells that give rise to aggressive metastatic variants. A viewpoint presented here addresses the implications of these studies for human cancer metastasis

    Matrix metalloproteinase-2 is a consistent prognostic factor in gastric cancer

    Get PDF
    In a pioneer study, we showed 10 years ago that enhanced tissue levels of the matrix metalloproteinases (MMPs) MMP-2 and MMP-9 in gastric cancers, as determined by zymography, were related with worse overall survival of the patients. To corroborate these observations, we now assessed MMP-2 and MMP-9 with new techniques in an expanded group of gastric cancer patients (n=81) and included for comparison MMP-7, MMP-8 and the tissue inhibitors of MMPs, TIMP-1 and -2. All MMPs and TIMP-1 were significantly increased in tumour tissue compared to normal gastric mucosa. Matrix metalloproteinase-7, -8 and -9, and the TIMPs showed some correlations with the clinicopathologic parameters TNM, WHO and Laurén classification, but their levels were not related with survival. Regardless of the determination method used, that is, enzyme-linked immunosorbent assay or bioactivity assay, an enhanced tumour MMP-2 level did not show a significant correlation with any of the clinicopathological parameters, but was confirmed to be an independent prognostic factor in gastric cancer

    Quantum Dots for Multiplexed Detection and Characterisation of Prostate Cancer Cells Using a Scanning Near-Field Optical Microscope

    Get PDF
    In this study scanning near-field optical microscopy (SNOM) has been utilised in conjunction with quantum dot labelling to interrogate the biomolecular composition of cell membranes. The technique overcomes the limits of optical diffraction found in standard fluorescence microscopy and also yields vital topographic information. The technique has been applied to investigate cell-cell adhesion in human epithelial cells. This has been realised through immunofluorescence labelling of the cell-cell adhesion protein E-cadherin. Moreover, a dual labelling protocol has been optimised to facilitate a comparative study of the adhesion mechanisms and the effect of aberrant adhesion protein expression in both healthy and cancerous epithelial cells. This study reports clear differences in the morphology and phenotype of healthy and cancerous cells. In healthy prostate epithelial cells (PNT2), E-cadherin was predominantly located around the cell periphery and within filopodial extensions. The presence of E-cadherin appeared to be enhanced when cell-cell contact was established. In contrast, examination of metastatic prostate adenocarcinoma cells (PC-3) revealed no E-cadherin labelling around the periphery of the cells. This lack of functional E-cadherin in PC-3 cells coincided with a markedly different morphology and PC-3 cells were not found to form close cell-cell associations with their neighbours. We have demonstrated that with a fully optimised sample preparation methodology, multiplexed quantum dot labelling in conjunction with SNOM imaging can be successfully applied to interrogate biomolecular localisation within delicate cellular membranes

    A comparative evaluation of various invasion assays testing colon carcinoma cell lines

    Get PDF
    Various colon carcinoma cell lines were tested in different invasion assays, i.e. invasion into Matrigel, into confluent fibroblast layers and into chicken heart tissue. Furthermore, invasive capacity and metastatic potential were determined in nude mice. The colon carcinoma cells used were the human cell lines Caco-2, SW-480, SW-620 and HT-29, and the murine lines Colon-26 and -38. None of the human colon carcinoma cells migrated through porous membranes coated with Matrigel; of the murine lines, only Colon-26 did. When incubated in a mixture of Matrigel and culture medium non-invading cells formed spheroid cultures, whereas invading cells showed a stellate outgrowth. Only the heterogeneously shaped (epithelioid and stellate) cells of SW-480 and SW-620 and the spindle-shaped cells of Colon-26 invaded clearly confluent skin and colon fibroblasts as well as chicken heart tissue. However, when transplanted into the caecum of nude and syngeneic mice, all the lines tested were invasive with the exception of Caco-2 cells. We conclude that the outcome of in vitro tests measuring the invasive capacity of neoplastic cells is largely dependent on the test system used. Invasive capacity in vitro is strongly correlated with cells having a spindle cell shape, vimentin expression and E-cadherin down regulation. In contrast, HT-29 and Colon-38 cells having an epithelioid phenotype were clearly invasive and metastatic in vivo, but not in vitro. © 1999 Cancer Research Campaig

    Synthetic emmprin peptides with chitobiose substitution stimulate MMP-2 production by fibroblasts

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Emmprin, a glycoprotein containing two Ig domains, is enriched on tumor cell surfaces and stimulates matrix metalloproteinase (MMP) production by adjacent stromal cells. Its first Ig domain (ECI) contains the biologically active site. The dependence of emmprin activity on N-glycosylation is controversial. We investigated whether synthetic ECI with the shortest sugar is functionally active.</p> <p>Methods</p> <p>The whole ECI peptides carrying sugar chains, a chitobiose unit or N-linked core pentasaccharide, were synthesized by the thioester method and added to fibroblasts to examine whether they stimulate MMP-2 production.</p> <p>Results</p> <p>ECI carrying a chitobiose unit, ECI-(GlcNAc) <sub>2</sub>, but not ECI without a chitobiose unit or the chitobiose unit alone, dose-dependently stimulated MMP-2 production by fibroblasts. ECI with longer chitobiose units, ECI-[(Man)<sub>3</sub>(GlcNAc)<sub>2</sub>], also stimulated MMP-2 production, but the extent of its stimulation was lower than that of ECI-(GlcNAc)<sub>2</sub>.</p> <p>Conclusions</p> <p>Our results indicate that ECI can mimic emmprin activity when substituted with chitobiose, the disaccharide with which N-glycosylation starts.</p

    Matrix metalloproteinases 2 and 9 (gelatinases A and B) expression in malignant mesothelioma and benign pleura

    Get PDF
    Matrix metalloproteinases (MMPs), in particular the gelatinases (MMP-2 and -9), play a significant role in tumour invasion and angiogenesis. The expression and activities of MMPs have not been characterised in malignant mesothelioma (MM) tumour samples. In a prospective study, gelatinase activity was evaluated in homogenised supernatants of snap frozen MM (n = 35), inflamed pleura (IP, n = 12) and uninflammed pleura (UP, n = 14) tissue specimens by semiquantitative gelatin zymography. Matrix metalloproteinases were correlated with clinicopathological factors and with survival using Kaplan-Meier and Cox proportional hazard models. In MM, pro- and active MMP-2 levels were significantly greater than for MMP-9 (P = 0.006, P<0.001). Active MMP-2 was significantly greater in MM than in UP (P=0.04). MMP-2 activity was equivalent between IP and MM, but both pro- and active MMP-9 activities were greater in IP (P=0.02, P=0.009). While there were trends towards poor survival with increasing total and pro-MMP-2 activity (P=0.08) in univariate analysis, they were both independent poor prognostic factors in multivariate analysis in conjunction with weight loss (pro-MMP-2 P = 0.03, total MMP-2 P = 0.04). Total and pro-MMP-2 also contributed to the Cancer and Leukemia Group B prognostic groups. MMP-9 activities were not prognostic. Matrix metalloproteinases, and in particular MMP-2, the most abundant gelatinase, may play an important role in MM tumour growth and metastasis. Agents that reduce MMP synthesis and/or activity may have a role to play in the management of MM. © 2003 Cancer Research UK
    • …
    corecore