Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Allergy ; 67(1): 25-32, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21899560

RESUMO

BACKGROUND: Chronic rhinosinusitis (CRS) is a heterogeneous disease characterized by local inflammation of the upper airways and sinuses and is frequently divided into polypoid CRS (CRSwNP) and nonpolypoid CRS (CRSsNP). However, the mechanism of inflammation in CRS has still not been fully elucidated. The aim of the study was to investigate the role of interleukin-32 (IL-32), a recently discovered proinflammatory cytokine, in CRS. METHODS: We collected nasal epithelial cells and nasal tissue from patients with CRS and control subjects. We assayed mRNA for IL-32 by real-time PCR and measured IL-32 protein using ELISA, Western blot, and immunohistochemistry. RESULTS: The expression of mRNA for IL-32 was elevated in epithelial cells from uncinate tissue from patients with CRSsNP compared with patients with CRSwNP (P < 0.05), control subjects (P=0.06), and epithelial cells from nasal polyp (NP) tissue (P < 0.05). Production of IL-32 was induced by IFN-γ, TNF, and dsRNA in primary airway epithelial cells. In whole-tissue extracts, the expression of IL-32 protein was significantly elevated in patients with CRSwNP compared with patients with CRSsNP and control subjects. Immunohistochemistry data showed that IL-32 was detected in mucosal epithelial cells and inflammatory cells in the lamina propria. Levels of IL-32 were correlated with the levels of CD3 and macrophage mannose receptor in NP tissue. Immunofluorescence data showed IL-32 co-localization with CD3-positive T cells and CD68-positive macrophages in NPs. CONCLUSION: Overproduction of IL-32 may be involved in the pathogenesis of CRS, although the role of IL-32 in the inflammation in CRSsNP and CRSwNP may be different.


Assuntos
Interleucinas/biossíntese , Pólipos Nasais/metabolismo , Rinite/metabolismo , Sinusite/metabolismo , Adolescente , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Interleucinas/análise , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Pólipos Nasais/complicações , Pólipos Nasais/imunologia , RNA Mensageiro/análise , Rinite/complicações , Rinite/imunologia , Sinusite/complicações , Sinusite/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Adulto Jovem
2.
J Hazard Mater ; 161(2-3): 1522-9, 2009 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-18562090

RESUMO

The liquid-phase adsorption of phenol onto coconut shell-based activated carbon, CS850A was investigated for its equilibrium studies and kinetic modeling. Coconut shell was converted into high quality activated carbon through physiochemical activation at 850 degrees C under the influence of CO(2) flow. Beforehand, the coconut shell was carbonized at 700 degrees C and the resulted char was impregnated with KOH at 1:1 weight ratio. In order to evaluate the performance of CS850A, a series of batch adsorption experiments were conducted with initial phenol concentrations ranging from 100 to 500 mg l(-1), adsorbent loading of 0.2g and the adsorption process was maintained at 30+/-1 degrees C. The adsorption isotherms were in conformation to both Langmuir and Freundlich isotherm models. Chemical reaction was found to be a rate-controlling parameter to this phenol-CS850A batch adsorption system due to strong agreement with the pseudo-second-order kinetic model. Adsorption capacity for CS850A was found to be 205.8 mg g(-1).


Assuntos
Carbono/química , Fenol/química , Adsorção , Físico-Química/métodos , Cocos , Cinética , Fenóis/química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Temperatura , Fatores de Tempo , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
3.
Cytogenet Genome Res ; 123(1-4): 65-78, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19287140

RESUMO

Microdeletions of 3q29 have previously been reported, but the postulated reciprocal microduplication has only recently been observed. Here, cases from four families, two ascertained in Toronto (Canada) and one each from Edinburgh (UK) and Leiden (Netherlands), carrying microduplications of 3q29 are presented. These families have been characterized by cytogenetic and molecular techniques, and all individuals have been further characterized with genome-wide, high density single nucleotide polymorphism (SNP) arrays run at a single centre (The Centre for Applied Genomics, Toronto). In addition to polymorphic copy-number variants (CNV), all carry duplications of 3q29 ranging in size from 1.9 to 2.4 Mb, encompassing multiple genes and defining a minimum region of overlap of about 1.6 Mb bounded by clusters of segmental duplications that is remarkably similar in location to previously reported 3q29 microdeletions. Consistent with other reports, the phenotype is variable, although developmental delay and significant ophthalmological findings were recurrent, suggesting that dosage sensitivity of genes located within 3q29 is important for eye and CNS development. We also consider CNVs found elsewhere in the genome for their contribution to the phenotype. We conclude by providing preliminary guidelines for management and anticipatory care of families with this microduplication, thereby establishing a standard for CNV reporting.


Assuntos
Cromossomos Humanos/genética , Dosagem de Genes/genética , Duplicação Gênica , Predisposição Genética para Doença/genética , Feminino , Guias como Assunto , Humanos , Masculino
4.
Mol Biochem Parasitol ; 94(2): 175-84, 1998 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9747968

RESUMO

Prenylated proteins have been shown to function in important cellular regulatory processes including signal transduction. The enzymes involved in protein prenylation, farnesyl transferase and geranylgeranyl transferase, have been recent targets for development of cancer chemotherapeutics. We have initiated a systematic study of protein prenyl transferases of the malaria parasite, Plasmodium falciparum, to determine whether these enzymes can be developed as targets for antimalarial chemotherapy. We report here the identification of protein farnesyl transferase and protein geranylgeranyl transferase-I in the malaria parasite, P. falciparum. The farnesyl transferase has been partially purified from the cytosolic fraction through ammonium sulfate precipitation and Mono-Q chromatography. Farnesyl and geranylgeranyl transferase-I activities are present at all stages of P. falciparum intraerythrocytic development with maximum specific activity in the ring stage. Geranylgeranyl transferase-I specific activity is two times that of farnesyl transferase in the ring stage. Peptidomimetics and prenyl analogues of protein farnesyl transferase substrates were tested as in vitro inhibitors of partially purified P. falciparum prenyl transferase and of malaria parasite growth. The peptidomimetics were significantly more potent inhibitors than lipid substrate analogues of both the activity of Mono-Q purified enzyme and parasite growth in intraerythrocytic cultures. Exposure of the parasite to the peptidomimetic L-745,631 also showed significant inhibition of morphological development beyond the trophozoite stage. These studies suggest the potential of designing or identifying differential inhibitors of P. falciparum and mammalian prenyl transferases as an approach to novel malaria therapy.


Assuntos
Alquil e Aril Transferases/metabolismo , Plasmodium falciparum/enzimologia , Prenilação de Proteína , Alquil e Aril Transferases/antagonistas & inibidores , Alquil e Aril Transferases/isolamento & purificação , Animais , Cromatografia , Eritrócitos/parasitologia , Farnesiltranstransferase , Humanos , Plasmodium falciparum/crescimento & desenvolvimento
5.
Clin Nephrol ; 61(5): 324-36, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15182127

RESUMO

BACKGROUND/AIMS: Advanced glycated end products (AGE) are endogenous proteins that have formed covalent complexes with sugars by a nonenzymatic process. Being proinflammatory molecules, AGE are thought to contribute to chronic systemic and local inflammatory processes associated with pathological changes in various diseases. In patients with end-stage renal disease, AGE are believed to play a role in the progression of atherosclerosis and worsening of renal failure. In patients receiving hemodialysis, AGE are thought to contribute to the inflammatory components of the therapy, particularly in diabetic patients. METHODS: In the present study, AGE were produced using 5% human serum albumin (HSA) and 50% glucose, both used for intravenous infusion into humans and both released after strict control for endotoxin content. The presence of AGE formed by HSA and glucose was confirmed using 2 independent assays. The inflammatory properties of these AGE were assessed using synthesis and release of the proinflammatory cytokines interleukin-1 (IL-1), tumor necrosis factor (TNF) and IL-8, a chemokine. RESULTS: Alone, AGE did not induce these cytokines from peripheral blood mononuclear cells (PBMC) obtained from 14 healthy human donors. However, in the presence of 1 or 10 ng/ml of endotoxin, AGE augmented the production of IL-1 and TNF above that induced by endotoxin alone. Although the amount of augmentation of LPS-induced cytokines by AGE varied between the blood donors, the response was consistently observed and reached statistical significance. The augmentation of cytokine production was confirmed using AGE prepared with different lots of HSA and glucose. CONCLUSION: These results demonstrate that in the strict absence ofendotoxins, AGE are formed that do not stimulate cytokine production from PBMC of healthy donors, however, AGE significantly augment the synthesis and release of proinflammatory cytokine in the presence of low concentrations of endotoxins. The data suggest that renal replacement therapies should consider the role of microbial products in potentiating the biological consequences of naturally formed AGE and their potential to contribute to systemic and local inflammation in renal replacement therapies. Therefore, although the formation of AGE is unavoidable, excluding microbial products during renal replacement therapy should reduce the pathological consequences of AGE.


Assuntos
Produtos Finais de Glicação Avançada/farmacologia , Interleucina-1/biossíntese , Interleucina-8/biossíntese , Lipopolissacarídeos/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Adulto , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade
6.
J Hazard Mater ; 175(1-3): 126-32, 2010 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19879046

RESUMO

The adsorption of methylene blue (MB) from aqueous solution using a low-cost adsorbent, rejected tea (RT), has been studied by batch adsorption technique. The adsorption experiments were carried out under different conditions of initial concentration (50-500 mg/L), solution pH 3-12, RT dose (0.05-1g) and temperature (30-50 degrees C). The equilibrium data were fitted to Langmuir and Freundlich isotherms and the equilibrium adsorption was best described by the Langmuir isotherm model with maximum monolayer adsorption capacities found to be 147, 154 and 156 mg/g at 30, 40 and 50 degrees C, respectively. Three kinetic models, pseudo-first-order, pseudo-second-order and intraparticle diffusion were employed to describe the adsorption mechanism. The experimental results showed that the pseudo-second-order equation is the best model that describes the adsorption behavior with the coefficient of correlation R(2)>or=0.99. The results suggested that RT has high potential to be used as effective adsorbent for MB removal.


Assuntos
Azul de Metileno/isolamento & purificação , Chá , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Corantes/química , Corantes/isolamento & purificação , Difusão , Concentração de Íons de Hidrogênio , Resíduos Industriais , Cinética , Azul de Metileno/química , Microscopia Eletrônica de Varredura/métodos , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Poluentes Químicos da Água/química , Purificação da Água/economia
7.
J Biol Chem ; 274(46): 33105-13, 1999 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-10551881

RESUMO

The genome of Escherichia coli is composed of a single molecule of circular DNA with the length of about 47,000 kilobase pairs, which is associated with about 10 major DNA-binding proteins, altogether forming the nucleoid. We expressed and purified 12 species of the DNA-binding protein, i.e. CbpA (curved DNA-binding protein A), CbpB or Rob (curved DNA-binding protein B or right arm of the replication origin binding protein), DnaA (DNA-binding protein A), Dps (DNA-binding protein from starved cells), Fis (factor for inversion stimulation), Hfq (host factor for phage Q(beta)), H-NS (histone-like nucleoid structuring protein), HU (heat-unstable nucleoid protein), IciA (inhibitor of chromosome initiation A), IHF (integration host factor), Lrp (leucine-responsive regulatory protein), and StpA (suppressor of td(-) phenotype A). The sequence specificity of DNA binding was determined for all the purified nucleoid proteins using gel-mobility shift assays. Five proteins (CbpB, DnaA, Fis, IHF, and Lrp) were found to bind to specific DNA sequences, while the remaining seven proteins (CbpA, Dps, Hfq, H-NS, HU, IciA, and StpA) showed apparently sequence-nonspecific DNA binding activities. Four proteins, CbpA, Hfq, H-NS, and IciA, showed the binding preference for the curved DNA. From the apparent dissociation constant (K(d)) determined using the sequence-specific or nonspecific DNA probes, the order of DNA binding affinity were determined to be: HU > IHF > Lrp > CbpB(Rob) > Fis > H-NS > StpA > CbpA > IciA > Hfq/Dps, ranging from 25 nM (HU binding to the non-curved DNA) to 250 nM (Hfq binding to the non-curved DNA), under the assay conditions employed.


Assuntos
Proteínas de Ligação a DNA/genética , Escherichia coli/química , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sequência de Bases , Sondas de DNA , Proteínas de Ligação a DNA/química , Dimerização , Eletroforese em Gel de Poliacrilamida , Regulação Bacteriana da Expressão Gênica , Dados de Sequência Molecular , Conformação Proteica
8.
Genes Cells ; 5(8): 613-26, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10947847

RESUMO

BACKGROUND: The genome DNA of Escherichia coli is folded into the nucleosome-like structure, often called a nucleoid, by the binding of several DNA-binding proteins. We previously determined the specificity and affinity of DNA-binding for 12 species of the E. coli DNA-binding protein, and their intracellular concentrations at various growth phases. The intracellular localization of these proteins in E. coli could be predicted from these data, but no attempt has been made thus far to directly observe the intracellular distribution of the DNA-binding proteins. RESULTS: The intracellular localization in Escherichia coli of 10 species of the nucleoid-associated protein, three components of the transcripton apparatus, and three components of the translation machinery was investigated by indirect immuno-fluorescence microscopy. The DNA-binding proteins could be classified into two groups. The group-I proteins, including the major nucleoid-structural proteins, H-NS, HU, IHF, StpA and Dps, are distributed uniformly within the entire nucleoid. In contrast, the group-II proteins, which are presumed to possess regulatory activities of DNA functions accumulate at specific loci within the nucleoid, forming 2 (SeqA), 3-4 (CbpA and CbpB) and 6-10 (Fis and IciA) immuno-stained dots. Each immuno-stained dot may represent either the association of a hundred to one thousand molecules of each DNA-binding protein at a specific locus of the genome DNA or the assembly of protein-associated DNA segments from different domains of the folded genome. Both the RNA polymerase core enzyme and the sigma70 subunit are mainly associated with the nucleoid, but the anti-sigma70 factor (Rsd) appears to be accumulated at the boundary between the nucleoid and the cytosol in the stationary-phase cells. Here we show that the majority of Hfq is present in cytoplasm together with ribosomal proteins L7/L12 and RMF. CONCLUSION: The DNA-binding proteins of E. coli could be classified into two groups. One group proteins was distributed uniformly within the nucleoid, but the other group of proteins showed an irregular distribution, forming immuno-stained spots or clumps.


Assuntos
Proteínas de Ligação a DNA/isolamento & purificação , Proteínas de Escherichia coli , Escherichia coli/ultraestrutura , Proteínas de Bactérias/isolamento & purificação , Proteínas de Transporte/isolamento & purificação , Compartimento Celular , RNA Polimerases Dirigidas por DNA/isolamento & purificação , Fator Proteico para Inversão de Estimulação , Técnica Indireta de Fluorescência para Anticorpo , Fator Proteico 1 do Hospedeiro , Fatores Hospedeiros de Integração , Proteínas Repressoras/isolamento & purificação , Proteínas Ribossômicas/isolamento & purificação , Ribossomos
9.
J Bacteriol ; 181(20): 6361-70, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10515926

RESUMO

The genome DNA of Escherichia coli is associated with about 10 DNA-binding structural proteins, altogether forming the nucleoid. The nucleoid proteins play some functional roles, besides their structural roles, in the global regulation of such essential DNA functions as replication, recombination, and transcription. Using a quantitative Western blot method, we have performed for the first time a systematic determination of the intracellular concentrations of 12 species of the nucleoid protein in E. coli W3110, including CbpA (curved DNA-binding protein A), CbpB (curved DNA-binding protein B, also known as Rob [right origin binding protein]), DnaA (DNA-binding protein A), Dps (DNA-binding protein from starved cells), Fis (factor for inversion stimulation), Hfq (host factor for phage Q(beta)), H-NS (histone-like nucleoid structuring protein), HU (heat-unstable nucleoid protein), IciA (inhibitor of chromosome initiation A), IHF (integration host factor), Lrp (leucine-responsive regulatory protein), and StpA (suppressor of td mutant phenotype A). Intracellular protein levels reach a maximum at the growing phase for nine proteins, CbpB (Rob), DnaA, Fis, Hfq, H-NS, HU, IciA, Lrp, and StpA, which may play regulatory roles in DNA replication and/or transcription of the growth-related genes. In descending order, the level of accumulation, calculated in monomers, in growing E. coli cells is Fis, Hfq, HU, StpA, H-NS, IHF*, CbpB (Rob), Dps*, Lrp, DnaA, IciA, and CbpA* (stars represent the stationary-phase proteins). The order of abundance, in descending order, in the early stationary phase is Dps*, IHF*, HU, Hfq, H-NS, StpA, CbpB (Rob), DnaA, Lrp, IciA, CbpA, and Fis, while that in the late stationary phase is Dps*, IHF*, Hfq, HU, CbpA*, StpA, H-NS, CbpB (Rob), DnaA, Lrp, IciA, and Fis. Thus, the major protein components of the nucleoid change from Fis and HU in the growing phase to Dps in the stationary phase. The curved DNA-binding protein, CbpA, appears only in the late stationary phase. These changes in the composition of nucleoid-associated proteins in the stationary phase are accompanied by compaction of the genome DNA and silencing of the genome functions.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Cromossomos Bacterianos/química , Proteínas de Ligação a DNA/isolamento & purificação , Proteínas de Escherichia coli , Escherichia coli/química , Escherichia coli/crescimento & desenvolvimento , Chaperonas Moleculares , Proteínas de Transporte/isolamento & purificação , Fator Proteico para Inversão de Estimulação , Fator Proteico 1 do Hospedeiro , Fatores Hospedeiros de Integração , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Receptores Imunológicos/isolamento & purificação
10.
Proc Natl Acad Sci U S A ; 98(6): 3304-9, 2001 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-11248074

RESUMO

IL-18 can be considered a proinflammatory cytokine mediating disease as well as an immunostimulatory cytokine that is important for host defense against infection and cancer. The high-affinity, constitutively expressed, and circulating IL-18 binding protein (IL-18BP), which competes with cell surface receptors for IL-18 and neutralizes IL-18 activity, may act as a natural antiinflammatory as well as immunosuppressive molecule. In the present studies, the IL-18 precursor caspase-1 cleavage site was changed to a factor Xa site, and, after expression in Escherichia coli, mature IL-18 was generated by factor Xa cleavage. Mature IL-18 generated by factor Xa cleavage was fully active. Single point mutations in the mature IL-18 peptide were made, and the biological activities of the wild-type (WT) IL-18 were compared with those of the mutants. Mutants E42A and K89A exhibited 2-fold increased activity compared with WT IL-18. A double mutant, E42A plus K89A, exhibited 4-fold greater activity. Unexpectedly, IL-18BP failed to neutralize the double mutant E42A plus K89A compared with WT IL-18. The K89A mutant was intermediate in being neutralized by IL-18BP, whereas neutralization of the E42A mutant was comparable to that in the WT IL-18. The identification of E42 and K89 in the mature IL-18 peptide is consistent with previous modeling studies of IL-18 binding to IL-18BP and explains the unusually high affinity of IL-18BP for IL-18.


Assuntos
Glicoproteínas/imunologia , Interleucina-18/imunologia , Células Cultivadas , Fator Xa/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Interleucina-18/genética , Interleucina-18/metabolismo , Interleucina-8/biossíntese , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Mutagênese Sítio-Dirigida , Testes de Neutralização , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/metabolismo
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa