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1.
J Biomed Mater Res A ; 107(4): 839-850, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30586231

RESUMO

Cell immobilization within nano-thin polymeric shells can provide an optimal concentration of biological material in a defined space and facilitate its directional growth. Herein, polyelectrolyte membrane scaffolds were constructed using a layer-by-layer approach to determine the possibility of promoting improved growth of rat cortical neuronal cells. Membrane presence was confirmed by Fourier transform infrared spectroscopy, Zeta potential, and atomic force and scanning electron microscopy. Scaffold performance toward neuronal cell growth was assessed in vitro during a 14-day culture. Cell conditions were analyzed immunocytochemically. Furthermore, western blot and real-time PCR analyses were used to validate the presence of neuronal and glial cells on the scaffolds. We observed that alginate/chitosan, alginate/polylysine, and polyethyleneimine/chitosan scaffolds promote neuronal growth similarly to the control, poly-d-lysine/laminin. We conclude that membranes maintaining cell viability, integrity and immobilization in systems supporting neuronal regeneration can be applied in neurological disease or wound healing treatment. © 2018 The Authors. Journal of Biomedical Materials Research Part A published by Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 839-850, 2019.


Assuntos
Membranas Artificiais , Neuroglia/metabolismo , Neurônios/metabolismo , Polieletrólitos/química , Alicerces Teciduais/química , Animais , Neuroglia/citologia , Neurônios/citologia , Ratos , Ratos Wistar
2.
Water Air Soil Pollut ; 228(8): 282, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28769141

RESUMO

This study investigated the use of ceramic membranes to remove total suspended solids (TSS), organics (expressed by chemical oxygen demand, COD), and bisphenol A (BPA) via microfiltration (MF, pore size 0.45 µm) and ultrafiltration (UF, cutoff 150 kDa) in post-treatment of effluents from aerobic granular sludge reactors (GSBRs). The efficiency of removal of COD, BPA, and TSS in MF was similar to that in UF; however, it was achieved at a lower pressure, which reduces energy consumption during the filtration process. Despite the similar quality of the permeates in MF and UF, the permeate flux averaged almost 20% higher in UF than in MF. The rejection coefficients were 77-82% for COD and 48-100% for BPA. In both MF and UF, TSS were totally removed. In the integrated system of aerobic granular sludge reactor and membrane installation, total removal of COD was 92-95% and that of BPA was above 98%, independently of the membrane technique. The high efficiency of BPA removal in MF and UF, despite pore sizes in the MF and UF membranes larger than the BPA molecules, suggests that some part of the BPA was first bound by particulate organic matter in the biologically treated wastewater before this sorbed form was removed by the membranes. Furthermore, the high removal of COD and BPA, even in MF, was attributed to adsorption on the membranes, in addition to sieve retention.

3.
Oncogene ; 36(34): 4875-4886, 2017 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-28414309

RESUMO

Molecular profiling of glioblastomas has revealed the presence of key signaling hubs that contribute to tumor progression and acquisition of resistance. One of these main signaling mechanisms is the nuclear factor-kappa B (NF-κB) pathway, which integrates multiple extracellular signals into transcriptional programs for tumor growth, invasion and maintenance of the tumor-initiating population. We show here that an extracellular protein released by glioblastoma cells, fibulin-3, drives oncogenic NF-κB in the tumor and increases NF-κB activation in peritumoral astrocytes. Fibulin-3 expression correlates with a NF-κB-regulated 'invasive signature' linked to poorer survival, being a possible tissue marker for regions of active tumor progression. Accordingly, fibulin-3 promotes glioblastoma invasion in a manner that requires NF-κB activation both in the tumor cells and their microenvironment. Mechanistically, we found that fibulin-3 activates the metalloprotease ADAM17 by competing with its endogenous inhibitor, TIMP3. This results in sustained release of soluble tumor necrosis factor alpha (TNFα) by ADAM17, which in turn activates TNF receptors and canonical NF-κB signaling. Taken together, our results underscore fibulin-3 as a novel extracellular signal with strong activating effect on NF-κB in malignant gliomas. Because fibulin-3 is produced de novo in these tumors and is absent from the normal brain, we propose that targeting the fibulin-3/NF-κB axis may provide a novel avenue to disrupt oncogenic NF-κB signaling in combination therapies for malignant brain tumors.


Assuntos
Neoplasias Encefálicas/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Glioblastoma/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/fisiologia , Microambiente Tumoral/fisiologia , Proteína ADAM17/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Progressão da Doença , Glioblastoma/patologia , Glioma/metabolismo , Glioma/patologia , Humanos , Masculino , Camundongos Nus , Invasividade Neoplásica/patologia , Receptores do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
4.
Folia Microbiol (Praha) ; 56(3): 201-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21618047

RESUMO

It is possible to cultivate aerobic granular sludge at a low organic loading rate and organics-to-total nitrogen (COD/N) ratio in wastewater in the reactor with typical geometry (height/diameter = 2.1, superficial air velocity = 6 mm/s). The noted nitrification efficiency was very high (99%). At the highest applied ammonia load (0.3 ± 0.002 mg NH (4) (+) -N g total suspended solids (TSS)(-1) day(-1), COD/N = 1), the dominating oxidized form of nitrogen was nitrite. Despite a constant aeration in the reactor, denitrification occurred in the structure of granules. Applied molecular techniques allowed the changes in the ammonia-oxidizing bacteria (AOB) community in granular sludge to be tracked. The major factor influencing AOB number and species composition was ammonia load. At the ammonia load of 0.3 ± 0.002 mg NH (4) (+) -N g TSS(-1) day(-1), a highly diverse AOB community covering bacteria belonging to both the Nitrosospira and Nitrosomonas genera accounted for ca. 40% of the total bacteria in the biomass.


Assuntos
Reatores Biológicos/microbiologia , Nitrogênio/metabolismo , Nitrosomonadaceae/metabolismo , Esgotos/microbiologia , Aerobiose , Amônia/metabolismo , Biomassa , Desnitrificação , Nitritos/metabolismo , Oxigênio/metabolismo , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água
5.
Oncogene ; 27(7): 918-30, 2008 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-17684491

RESUMO

The invasion of tumor cells into brain tissue is a pathologic hallmark of malignant gliomas and contributes to treatment failures. Diffuse glioblastomas contain numerous microglial cells, which enhance the progression of gliomas; however, factors responsible for invasion-promoting role of microglia are unknown. Transforming growth factor-beta (TGF-beta) can enhance tumor growth, invasion, angiogenesis and immunosuppression. Antagonizing TGF-beta activity has been shown to inhibit tumor invasion in vitro and tumorigenicity, but a systemic inhibition or lack of TGF-beta signaling results in acute inflammation and disruption of immune system homeostasis. We developed plasmid-transcribed small hairpin RNAs (shRNAs) to downregulate the TGF-beta type II receptor (TbetaIIR) expression, which effectively inhibited cytokine-induced signaling pathways and transcriptional responses in transiently transfected human glioblastoma cells. Silencing of TbetaIIR abolished TGF-beta-induced glioblastoma invasiveness and migratory responses in vitro. Moreover, tumorigenicity of glioblastoma cells stably expressing TbetaIIR shRNAs in nude mice was reduced by 50%. Microglia strongly enhanced glioma invasiveness in the co-culture system, but this invasion-promoting activity was lost in glioma cells stably expressing shTbetaRII, indicating a crucial role of microglia-derived TGF-beta in tumor-host interactions. Our results demonstrate a successful targeting of TGF-beta-dependent invasiveness and tumorigenicity of glioblastoma cells by RNAi-mediated gene silencing.


Assuntos
Movimento Celular/fisiologia , Inativação Gênica/fisiologia , Glioma/patologia , Microglia/metabolismo , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Fator de Crescimento Transformador beta/metabolismo , Animais , Técnicas de Cocultura , Colágeno/metabolismo , Combinação de Medicamentos , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Glioma/metabolismo , Humanos , Laminina/metabolismo , Masculino , Camundongos , Camundongos Nus , Invasividade Neoplásica , Proteínas Serina-Treonina Quinases/metabolismo , Proteoglicanas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Transfecção , Células Tumorais Cultivadas
6.
J Appl Microbiol ; 101(1): 190-9, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16834606

RESUMO

AIMS: Knowledge of the species composition of complex bacterial communities is still very limited. The main objectives of this study were to identify medium-chain-length polyhydroxyalkanoates (mcl-PHAs)-producing bacteria from activated sludge fed with methanol as well as to characterize their PHA operon. METHODS AND RESULTS: The identification was based on PCR amplification of mcl-PHA synthase gene fragments. In the analysed sample, four isolates possessing mcl-PHA synthesis systems were distinguished. The results of a 16S rDNA sequence analysis revealed that three strains belonged to Pseudomonas species and the fourth one was characterized as Comamonas testosteroni. CONCLUSIONS: The results of this study indicate that the PCR-RFLP approach is an excellent way to identify mcl-PHA-synthesizing micro-organisms. The discovery of 4 genetic variants, among the 20 analysed, demonstrates that microbial diversity of activated sludge is high and thus offers a great opportunity for the discovery of novel gene forms. SIGNIFICANCE AND IMPACT OF THE STUDY: An important discovery of this study is that C. testosteroni could harbour mcl-PHA operon. Moreover, the results obtained indicate that PHAs synthesis ability can be spread by horizontal gene transfer. The results of a comparative phylogenetic analysis revealed that mcl-PHA-synthesizing bacteria can be divided into Pseudomonas fluorescens and Pseudomonas aeruginosa groups.


Assuntos
Bactérias/genética , DNA Bacteriano/análise , Ecossistema , Variação Genética , Microbiologia da Água , Aciltransferases/genética , Bactérias/metabolismo , Sequência de Bases , Fermentação , Metanol , Dados de Sequência Molecular , Óperon , Filogenia , Polimorfismo de Fragmento de Restrição
7.
Blood Cells Mol Dis ; 26(1): 84-90, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10772879

RESUMO

The ETS family member Tel is rearranged in human leukemia of both myeloid and lymphoid origin while the ETS member Fli-1 is insertionally activated in Friend erythroleukemia in mice and is translocated to the EWS locus in Ewing's sarcoma. In previous studies we demonstrated that Tel binds to Fli-1 and blocks transactivation of megakaryocytic promoters by Fli-1. In this study we demonstrate that expression of Fli-1 in the leukemia cell line K562 induces a megakaryocytic phenotype and the expression of the platelet markers GPIX, GP1balpha, and GPIIb. Introduction of Tel blocked the megakaryocytic phenotype induced by Fli-1, suggesting a biological correlation to the biochemical interaction of Tel and Fli-1 reported previously.


Assuntos
Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/farmacologia , Células-Tronco Hematopoéticas/metabolismo , Proteínas Proto-Oncogênicas , Proteínas Repressoras , Transativadores/antagonistas & inibidores , Fatores de Transcrição/farmacologia , Biomarcadores , Western Blotting , Clonagem Molecular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células K562 , Megacariócitos/citologia , Megacariócitos/efeitos dos fármacos , Megacariócitos/imunologia , Família Multigênica , Fenótipo , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/biossíntese , Complexo Glicoproteico GPIb-IX de Plaquetas/biossíntese , Proteína Proto-Oncogênica c-fli-1 , Proteínas Proto-Oncogênicas c-ets , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Células Tumorais Cultivadas/química , Variante 6 da Proteína do Fator de Translocação ETS
8.
J Biol Chem ; 273(28): 17525-30, 1998 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-9651344

RESUMO

The tel gene, recently shown to be translocated in a spectrum of acute and chronic human leukemias, belongs to the ets family of sequence-specific transcription factors. To determine the role of Tel in normal hematopoietic development, we used the tel gene as the bait in the yeast two-hybrid system to screen a hematopoietic stem cell library. Two partners were identified: Tel binds to itself, and Tel binds to the ets family member Fli-1. In vitro and in vivo assays confirmed these interactions. In transient transfection assays, Fli-1 transactivates megakaryocytic specific promoters, and Tel inhibits this effect of Fli-1. Transactivation studies using deletion mutants of Tel, and the Tel-AML-1 fusion protein, indicate that the helix-loop-helix domain of Tel only partially inhibits transactivation and that complete inhibition requires the full-length Tel molecule, including the DNA binding domain. The Tel and Fli-1 proteins are expressed early in hematopoiesis, and the inability of Tel fusion proteins such as Tel-AML-1 to counteract Fli-1 mediated transactivation may contribute to the malignant phenotype in human leukemias where this fusion protein is present.


Assuntos
Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/metabolismo , Proteínas Proto-Oncogênicas , Proteínas Repressoras , Transativadores/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Ativação Transcricional , Sequência de Bases , Diferenciação Celular , Primers do DNA , Proteínas de Ligação a DNA/química , Sequências Hélice-Alça-Hélice , Fatores de Crescimento de Células Hematopoéticas/farmacologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Fases de Leitura Aberta , Proteína Proto-Oncogênica c-fli-1 , Proteínas Proto-Oncogênicas c-ets , Fatores de Transcrição/química , Células Tumorais Cultivadas , Variante 6 da Proteína do Fator de Translocação ETS
9.
Gene ; 165(2): 219-22, 1995 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-8522179

RESUMO

Two cDNAs encoding calnexin (Cln)-like and calreticulin (Crl)-like proteins have been isolated by immunoscreening of a maize leaf cDNA library. In the deduced amino acid (aa) sequences, several regions that are conserved for Cln and Crl proteins from all sources have been identified. These regions can be classified into two distinct motifs which are repeated four times each in Cln and three times each in Crl sequences. One of these motifs, containing a highly acidic 17-aa sequence, has high homology to a Ca(2+)-binding domain previously characterized in both Cln and Crl from mammalian tissues. Motifs for retention in endoplasmic reticulum (Crl) and for an integral membrane-spanning sequence (Cln) have also been identified.


Assuntos
Proteínas de Ligação ao Cálcio/genética , DNA Complementar/genética , Genes de Plantas/genética , Ribonucleoproteínas/genética , Zea mays/genética , Sequência de Aminoácidos , Cálcio/metabolismo , Calnexina , Calreticulina , Clonagem Molecular , DNA de Plantas/genética , Retículo Endoplasmático , Membranas Intracelulares , Dados de Sequência Molecular , Proteínas de Plantas/genética , Sequências Repetitivas de Ácido Nucleico/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
11.
Czas Stomatol ; 43(2): 111-4, 1990 Feb.
Artigo em Polonês | MEDLINE | ID: mdl-2104325

RESUMO

The position of the connective tissue attachment was determined by Ramfjord's method in subjects aged 20-29 and 40-49 years. In the determination four surfaces of all remaining incisors, canines, and premolars were considered. A defect of the connective tissue attachment was found in about 95% of the analysed dental surfaces in subjects aged 40-49 years. The frequency of occurrence of these defects varied depending on the type dental surface.


Assuntos
Doenças Periodontais/patologia , Adulto , Tecido Conjuntivo/patologia , Humanos , Pessoa de Meia-Idade , Ligamento Periodontal/patologia
12.
Czas Stomatol ; 42(4): 279-82, 1989 Apr.
Artigo em Polonês | MEDLINE | ID: mdl-2487850

RESUMO

In 20 subjects aged 20-29 years the position of the connective tissue attachment was determined and the atrophy of the alveolar process bone was assessed by means of an analysis of pantomograms. The radiological image of the paradontium was compared with the result of clinical examination. It was found that radiological diagnosis by means of pantomography may be a valuable supplementation of clinical examination in case of advanced parodontitis with loss of connective tissue attachment by at least 6 mm.


Assuntos
Perda do Osso Alveolar/diagnóstico por imagem , Radiografia Panorâmica , Adulto , Tecido Conjuntivo/patologia , Inserção Epitelial/patologia , Humanos , Ligamento Periodontal/patologia , Periodontite/diagnóstico por imagem
18.
Nahrung ; 27(5): 469-78, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6684211

RESUMO

As the result of sensory and gas chromatographic investigation of the edible mushrooms Xerocomus badius and Tricholoma equestre aroma properties it was stated that freezing preserves the general character of typical aroma. The observed changes were mostly favourable for sensory value intensifying the characteristic for investigated species small and, in the case of T. equestre, lowering the threshold concentration.


Assuntos
Agaricales , Basidiomycota , Congelamento , Cromatografia Gasosa/métodos , Odorantes
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