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1.
Environ Monit Assess ; 156(1-4): 119-30, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18683058

RESUMO

Mercury emissions from some upstream gold mining areas and recent findings of high natural Hg levels in sediments motivated studies on the Hg cycle in the Minas Gerais state. The study presents the total mercury amount found in Geophagus brasiliensis' muscular tissue (wet weight) and sediments from Piracicaba River. Mercury was analyzed using acid digestion followed by determination of total mercury by cold vapour atomic absorption spectrophotometry. This study was also complemented with the analysis of the limnological parameters (water temperature, conductivity, total dissolved solids, suspended particles, pH, dissolved oxygen, maximum depth, photic index and total carbon). The mercury concentration in sediments samples was higher than the mercury concentration in muscular tissue of fish. The lowest Hg level measured in fish was 0.0147 microg g( - 1), while the highest was 0.101 microg g( - 1). In the sediment samples, the lowest and highest levels were 0.02 microg g( - 1) and 0.16 microg g( - 1), respectively. The Hg concentrations in fish and sediment were both under the maximum limit permitted by the World Health Organization.


Assuntos
Monitoramento Ambiental/métodos , Peixes/metabolismo , Mercúrio/análise , Mercúrio/metabolismo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Animais , Brasil , Sedimentos Geológicos/análise
2.
Biomaterials ; 154: 34-47, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29120817

RESUMO

Efficient cell delivery strategies are urgently needed to improve the outcome of cell-based pro-angiogenic therapies. This study describes the design of an injectable cell delivery platform, based on biomaterial-guided morphogenesis principles. Soft high-mannuronic acid alginate microgels, oxidized and functionalized with integrin-binding peptides, provided adequate biochemical/biomechanical cues for the co-assembly of mesenchymal stem cells and outgrowth endothelial cells (OEC) into pre-vascularized microtissues. In vitro priming conditions regulated OEC tubulogenesis, which only occurred under normoxia (+O2) in the presence of angiogenic factors (+GF) and, importantly, did not revert in an ischemic-like environment. Primed (+O2+GF) microgel-entrapped cells secreted a large variety of angiogenesis-related proteins and produced endogenous extracellular-matrix, rich in fibronectin and collagen type I, fostering cell-cell/cell-matrix interactions and establishing a stable angiogenic niche. Extending the pre-culture time resulted in higher cell outward migration and in vivo angiogenic potential. Microgels partially disintegrated upon implantation in chick embryos, promoting interaction between pre-vascularized microtissues and the host. Preserved human vascular structures were still detected in vivo, and human cells showed the ability to migrate and integrate with the chick vasculature. Our results suggest that an integrated approach combining pro-angiogenic cells, cell-instructive microgels and adequate in vitro priming may provide the basis for successful therapeutic angiogenesis.


Assuntos
Géis/química , Morfogênese , Neovascularização Patológica/terapia , Alginatos/química , Animais , Movimento Celular/efeitos dos fármacos , Microambiente Celular/efeitos dos fármacos , Embrião de Galinha , Células Endoteliais/citologia , Matriz Extracelular/metabolismo , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Células-Tronco Mesenquimais/citologia , Neovascularização Patológica/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Oligopeptídeos/farmacologia , Oxigênio/farmacologia
3.
Int J Oral Maxillofac Surg ; 36(6): 552-5, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17467240

RESUMO

A haemophilic pseudotumour is basically an encapsulated haematoma. It is an infrequent complication, estimated to affect 1-2% of severe haemophiliacs, although it has also been reported in patients with mild and moderate haemophilia. A history of trauma is reported in most cases, and the onset of symptoms varies from months to years. The majority of haemophilic pseudotumours are seen in adults and occur in long bones (femur, pelvis, tibia). Here are reported three cases of pseudotumour of the mandible in young patients with mild haemophilia A.


Assuntos
Hematoma/etiologia , Hemofilia A/complicações , Doenças Mandibulares/etiologia , Adolescente , Criança , Coagulantes/uso terapêutico , Diagnóstico Diferencial , Fator VIII/uso terapêutico , Hematoma/patologia , Hematoma/terapia , Humanos , Masculino , Doenças Mandibulares/patologia , Doenças Mandibulares/terapia
4.
Hum Mutat ; 17(6): 511-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11385709

RESUMO

Two germline retrotransposition mutations of recent origin were observed in 727 independent mutations (0.28%) in the human factor IX gene (F9) of patients with hemophilia B: 1) a 279 bp insertion in exon H originating from an Alu family of short interspersed elements not previously known to be active and, 2) a 463 bp insertion in exon E of a LINE1 element originating in the maternal grandmother. If the rates of recent germline mutation in F9 are typical of the genome, a retrotransposition event is estimated to occur somewhere in the genome of about one in every 17 children born. Analysis of other estimates for retrotransposition frequency and overall mutation rates suggests that the actual rate of retrotransposition is likely to be in the range of one in every 2.4 to 28 live births.


Assuntos
Fator IX/genética , Retroelementos/genética , Elementos Alu/genética , Sequência de Aminoácidos , Sequência de Bases , DNA/genética , Frequência do Gene , Hemofilia B/genética , Humanos , Dados de Sequência Molecular , Mutagênese Insercional , Mutação , Homologia de Sequência do Ácido Nucleico
5.
Oncogene ; 33(16): 2123-33, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-23644655

RESUMO

The interactions between cancer cells and their microenvironment are crucial for malignant progression, as they modulate invasion-related activities. Tumor-associated macrophages are generally considered allies in the process of tumor progression in several types of cancer, although their role on gastric and colorectal carcinomas is still poorly understood. In this report, we studied the influence of primary human macrophages on gastric and colorectal cancer cells, considering invasion, motility/migration, proteolysis and activated intracellular signaling pathways. We demonstrated that macrophages stimulate cancer cell invasion, motility and migration, and that these effects depend on matrix metalloproteinase (MMP) activity and on the activation of epidermal growth factor receptor (EGFR) (at the residue Y(1086)), PLC-γ (phospholipase C-gamma) and Gab1 (GRB2-associated binding protein-1), as evidenced by siRNA (small interference RNA) experiments. Epidermal growth factor (EGF)-immunodepletion impaired macrophage-mediated cancer cell invasion and motility, suggesting that EGF is the pro-invasive and pro-motile factor produced by macrophages. Macrophages also induced gastric and colorectal cancer cell phosphorylation of Akt, c-Src and ERK1/2, and led to an increase of RhoA and Cdc42 activity. Interestingly, whereas macrophage-mediated cancer cell c-Src and ERK1/2 phosphorylation occurred downstream EGFR activation, Akt phosphorylation seems to be a parallel event, taking place in an EGFR-independent manner. The involvement of EGF, EGFR-downstream signaling partners and MMPs in macrophage-mediated invasion provides novel insights into the molecular crosstalk established between cancer cells and macrophages, opening new perspectives for the design of new and more efficient therapeutic strategies to counteract cancer cell invasion.


Assuntos
Receptores ErbB/metabolismo , Macrófagos/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Western Blotting , Células CACO-2 , Linhagem Celular Tumoral , Movimento Celular , Células Cultivadas , Técnicas de Cocultura , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Receptores ErbB/genética , Humanos , Macrófagos/citologia , Metaloproteinases da Matriz/metabolismo , Microscopia Confocal , Microscopia de Fluorescência , Invasividade Neoplásica , Fosforilação , Interferência de RNA , Transdução de Sinais , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Imagem com Lapso de Tempo/métodos , Tirosina/genética , Tirosina/metabolismo
6.
Braz J Med Biol Res ; 46(8): 676-80, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24036939

RESUMO

Multipotent mesenchymal stromal cells (MSCs) were first isolated from bone marrow and then from various adult tissues including placenta, cord blood, deciduous teeth, and amniotic fluid. MSCs are defined or characterized by their ability to adhere to plastic, to express specific surface antigens, and to differentiate into osteogenic, chondrogenic, adipogenic, and myogenic lineages. Although the molecular mechanisms that control MSC proliferation and differentiation are not well understood, the involvement of microRNAs has been reported. In the present study, we investigated the role of miR-125b during osteoblastic differentiation in humans. We found that miR-125b increased during osteoblastic differentiation, as well as Runx2 and ALPL genes. To study whether the gain or loss of miR-125b function influenced osteoblastic differentiation, we transfected MSCs with pre-miR-125b or anti-miR-125b and cultured the transfected cells in an osteoblastic differentiation medium. After transfection, no change was observed in osteoblastic differentiation, and Runx2, OPN, and ALPL gene expression were not changed. These results suggest that the gain or loss of miR-125b function does not influence levels of Runx2, OPN, and ALPL during osteoblastic differentiation.


Assuntos
Fosfatase Alcalina/metabolismo , Diferenciação Celular/fisiologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , MicroRNAs/metabolismo , Osteoblastos/citologia , Osteopontina/metabolismo , Fosfatase Alcalina/genética , Antígenos de Diferenciação/isolamento & purificação , Células da Medula Óssea/citologia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Feminino , Expressão Gênica/fisiologia , Humanos , Leucócitos Mononucleares/citologia , Masculino , Células-Tronco Mesenquimais/citologia , MicroRNAs/genética , Osteoblastos/metabolismo , Osteogênese/fisiologia , Osteopontina/genética , Cultura Primária de Células , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
7.
Braz. j. med. biol. res ; 46(8): 676-680, ago. 2013. graf
Artigo em Inglês | LILACS | ID: lil-684529

RESUMO

Multipotent mesenchymal stromal cells (MSCs) were first isolated from bone marrow and then from various adult tissues including placenta, cord blood, deciduous teeth, and amniotic fluid. MSCs are defined or characterized by their ability to adhere to plastic, to express specific surface antigens, and to differentiate into osteogenic, chondrogenic, adipogenic, and myogenic lineages. Although the molecular mechanisms that control MSC proliferation and differentiation are not well understood, the involvement of microRNAs has been reported. In the present study, we investigated the role of miR-125b during osteoblastic differentiation in humans. We found that miR-125b increased during osteoblastic differentiation, as well as Runx2 and ALPL genes. To study whether the gain or loss of miR-125b function influenced osteoblastic differentiation, we transfected MSCs with pre-miR-125b or anti-miR-125b and cultured the transfected cells in an osteoblastic differentiation medium. After transfection, no change was observed in osteoblastic differentiation, and Runx2, OPN, and ALPL gene expression were not changed. These results suggest that the gain or loss of miR-125b function does not influence levels of Runx2, OPN, and ALPL during osteoblastic differentiation.


Assuntos
Feminino , Humanos , Masculino , Fosfatase Alcalina/metabolismo , Diferenciação Celular/fisiologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , MicroRNAs/metabolismo , Osteoblastos/citologia , Osteopontina/metabolismo , Fosfatase Alcalina/genética , Antígenos de Diferenciação/isolamento & purificação , Células da Medula Óssea/citologia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Expressão Gênica/fisiologia , Leucócitos Mononucleares/citologia , Células-Tronco Mesenquimais/citologia , MicroRNAs/genética , Osteoblastos/metabolismo , Osteogênese/fisiologia , Osteopontina/genética , Cultura Primária de Células , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
8.
Rev. bras. farmacogn ; 13(supl.1): 58-62, 2003. graf, tab
Artigo em Português | LILACS | ID: lil-526248

RESUMO

Há muitos anos, tenta-se implantar a fitoterapia no município de Maringá, o que só foi possível em 2000, com a criação de uma comissão específica, definição das plantas segundo critérios epidemiológicos, literatura disponível e adoção do formato de farmácia de manipulação. Foram padronizados os fitoterápicos nas formas de infusão (espinheira-santa, guaco, cavalinha, hortelã e funcho), gel (própolis e calêndula) e em cápsulas gelatinosas duras (valeriana). Encontrou-se problemas com fornecedores, com diversos lotes insatisfatórios quanto à qualidade, mas ao longo do tempo o programa foi muito bem aceito. Nestes três anos de funcionamento, já foram dispensados mais de 50.000 unidades de produtos, com destaque à aceitação e eficácia da valeriana como ansiolitico, dos géis de própolis e calendula como antimicrobiano e cicatrizante, da espinheirasanta em gastrites e úlceras e do guaco como broncodilator e expectorante. Confirma-se, assim, o valor da fitoterapia no apoio às atividades básicas de saúde.


There are many years, it tries to implant the phytotherapy in the municipal district of Maringá. That implantation was only possible in 2000, with the creation of specific commission, definition of the plants according to epidemic criteria and available literature, and adoption of the format of manipulation drugstore. We have standardized the phytotherapics in the infusion forms (espinheira-santa, guaco, cavalinha, mint and fennel), gel (própolis and calendula) and in hard gelatinous capsules (valerian). There were problems with suppliers, with several unsatisfactory lots as for the quality, but along the time the program was very well accepted. On these three years of operation, there were already released more than 50.000 units of products, with prominence to the acceptance and effectiveness of the valerian as ansiolitic, two gels of propolis and calendula as antimicrobial and healing, of the espinheirasanta in gastritis and ulcers and of the guaco as broncodilator and expectorant. It is confirmed, like this, the value of the phytotherapy in the support to the basic activities of health.

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