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1.
Br J Cancer ; 105(2): 320-6, 2011 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-21654679

RESUMO

BACKGROUND: We conducted the first analysis of viral microRNAs (miRNAs) in lung cancer, with a focus on Epstein-Barr virus (EBV). METHODS: We evaluated viral miRs with a two-channel oligo-array targeting mature, anti-sense miRNAs in 290 cases. In 48 cases, we compared microarray and real-time quantitative PCR (qPCR) expression for three EBV miRNAs. We tested for EBV DNA, RNA, and protein in tumour tissue from six cases with and six cases without strong qPCR-based evidence of EBV miRNAs. RESULTS: The EBV miRNAs strongly differentiated between adenocarcinoma and squamous cell carcinoma using the microarray (P<0.01 for 9 out of 16 EBV miRNAs). However, microarray and qPCR measurements of BART1, BART2, and BHRF1-3 expression were not significantly correlated (P=0.53, 0.94, and 0.47, respectively). Although qPCR provided substantial evidence of EBV miRNAs in 7 out of 48 cases, only 1 of these 7 cases had detectable EBV DNA in tumour tissue. None had detectable EBV RNA or protein by histochemical stains. CONCLUSION: In a comprehensive evaluation of EBV miRNA, DNA, RNA, and protein in lung cancer, we found little evidence of EBV in lung tumour tissue. Discrepancies between microarray- and qPCR-based strategies highlight the difficulty of validating molecular markers of disease. Our results do not support a role of EBV in lung cancer.


Assuntos
Adenocarcinoma/virologia , Carcinoma de Células Escamosas/virologia , Herpesvirus Humano 4/genética , Neoplasias Pulmonares/virologia , MicroRNAs/genética , Adenocarcinoma/complicações , Adenocarcinoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/genética , Estudos de Casos e Controles , DNA Viral/análise , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Herpesvirus Humano 4/isolamento & purificação , Herpesvirus Humano 4/fisiologia , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/genética , Masculino , MicroRNAs/análise , MicroRNAs/fisiologia , Análise em Microsséries , Pessoa de Meia-Idade , RNA Viral/análise , Proteínas Virais/análise
2.
Br J Cancer ; 103(12): 1870-4, 2010 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-21102586

RESUMO

BACKGROUND: MicroRNAs (miRs) have an important role in lung carcinogenesis and progression. Single-nucleotide polymorphisms (SNPs) in genes involved in miR biogenesis may affect miR expression in lung tissue and be associated with lung carcinogenesis and progression. METHODS: we analysed 12 SNPs in POLR2A, RNASEN and DICER1 genes in 1984 cases and 2073 controls from the Environment And Genetics in Lung cancer Etiology (EAGLE) study. We investigated miR expression profiles in 165 lung adenocarcinoma (AD) and 125 squamous cell carcinoma tissue samples from the same population. We used logistic and Cox regression models to examine the association of individual genotypes and haplotypes with lung cancer risk and with lung cancer-specific survival, respectively. SNPs-miR expression associations in cases were assessed using two-sample t-tests and global permutation tests. RESULTS: a haplotype in RNASEN (Drosha) was significantly associated with shorter lung cancer survival (hazard ratio=1.86, 95% CI=1.19-2.92, P=0.007). In AD cases, a SNP within the same haplotype was associated with reduced RNASEN mRNA expression (P=0.013) and with miR expression changes (global P=0.007) of miRs known to be associated with cancer (e.g., let-7 family, miR-21, miR-25, miR-126 and miR15a). CONCLUSION: inherited variation in the miR-processing machinery can affect miR expression levels and lung cancer-specific survival.


Assuntos
Neoplasias Pulmonares/genética , MicroRNAs/análise , Polimorfismo de Nucleotídeo Único , Interferência de RNA , RNA Helicases DEAD-box/genética , Haplótipos , Humanos , Neoplasias Pulmonares/mortalidade , Ribonuclease III/genética
3.
Phys Rev E Stat Nonlin Soft Matter Phys ; 74(1 Pt 1): 011706, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16907110

RESUMO

We present a combined experimental and Monte Carlo study of a nematic phase in the presence of quenched disorder. The turbidity of a nematic liquid crystal embedded in a porous polymer membrane is measured under different applied field conditions for field-cooled and zero-field-cooled samples. We find that a significant permanent alignment of the nematic can be induced by fields as low as 0.1 V/microm applied during the isotropic to nematic transition. An analogous effect and dependence on sample history is found by studying the order parameter of a sprinkled disorder Lebwohl-Lasher spin model, indicating that dilute quenched randomness is sufficient to produce memory effects in nematics. The large memory induced by field cooling appears to be written in the system during the transition as a result of the field action on freely oriented nematic nuclei. At lower temperature the nuclei consolidate into permanent nematic textures developed from the interaction with quenched disorder.

4.
Phys Rev Lett ; 94(9): 097802, 2005 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-15784001

RESUMO

Memory effects and glassy behavior have been repeatedly observed in disordered nematic liquid crystals but the connection between these effects and the system topology remained unrevealed. We present an analysis of the local and global topology of the nematic ordering in the presence of quenched disorder and we show that nematics with quenched disorder can be mapped into a system of pinned defect lines and that the memory of the system stems from the pinning of these strings.

7.
Minerva Urol Nefrol ; 41(3): 225-34, 1989.
Artigo em Italiano | MEDLINE | ID: mdl-2617380

RESUMO

Two thousand seven hundred samples, received as urinary calculi, in a Turin based laboratory, in the period between March 1979 and February 1989, were examined by infrared spectroscopy to identify components even of difficult characterization: a special procedure was used and it is described. Knowing the composition of each calculus, a comparison was made between the incidence of each compound in the first 1500 samples (1979-1984) and in the remaining 1200 ones (1984-1989). Besides an increase in calcium oxalate as main component, a marked reduction in incidence of struvite was found in the calculi belonging to the second period of observation. The possible interference in calculi composition by various therapy for renal infection is discussed.


Assuntos
Compostos de Magnésio , Cálculos Urinários/análise , Oxalato de Cálcio/análise , Humanos , Magnésio/análise , Fosfatos/análise , Espectrofotometria Infravermelho , Estruvita , Cálculos Urinários/etiologia , Infecções Urinárias/complicações
11.
Clin Nephrol ; 23(3): 134-41, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3886230

RESUMO

Deposits of C3 but not of C1q and C4 were detected on the proximal tubules of kidneys from nephrotic patients with non-selective proteinuria. The incidence of tubular C3 deposits was significantly higher in patients with membranous glomerulonephritis, focal glomerulosclerosis, membrano-proliferative glomerulonephritis and non-selective proteinuria than in patients with minimal change disease, nephrotic syndrome and selective proteinuria or in patients with glomerular disease, but without nephrotic syndrome. The occurrence of tubular C3 deposits was positively correlated with the amount of urinary C3 excretion. In vitro studies showed that the human normal kidney as well as pathologic specimens negative for in vivo tubular C3 deposits were able to bind C3 on the brush border of proximal tubules when incubated with fresh heterologous serum. In contrast, in patients with non-selective proteinuria and in vivo tubular C3 deposits, the binding of heterologous C3 to the brush border of proximal tubules was markedly reduced. The positive correlation between the occurrence of tubular C3 deposits and the urinary complement excretion, together with the detection of the C3 breakdown products in the urines further supported the hypothesis that complement components, once filtrated through the glomerular barrier, might be activated by the brush border of the proximal tubule.


Assuntos
Complemento C3/análise , Túbulos Renais Proximais/imunologia , Microvilosidades/imunologia , Síndrome Nefrótica/imunologia , Adolescente , Adulto , Idoso , Animais , Criança , Ativação do Complemento , Complemento C3/urina , Feminino , Imunofluorescência , Glomerulonefrite/complicações , Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Humanos , Imunoeletroforese , Rim/imunologia , Rim/patologia , Túbulos Renais Proximais/patologia , Masculino , Microvilosidades/patologia , Pessoa de Meia-Idade , Síndrome Nefrótica/complicações , Síndrome Nefrótica/patologia , Proteinúria/imunologia , Coelhos
14.
J Immunol ; 128(4): 1659-63, 1982 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7037953

RESUMO

The purpose of this study was to investigate which structures of the nephron, if any, are capable of directly activating the complement (C) system. To this end, two sets of experiments were performed. First, activation of C was assessed on sections of frozen kidney tissue, using the indirect immunofluorescence technique for the demonstration of C fixation. Second, glomerular or tubular fractions of kidney were incubated with normal fresh serum, and subsequent C consumption was measured. The data obtained support the interpretation that the brush border of proximal tubules activates the alternative pathway of the C system. This phenomenon may have pathogenic significance in conditions of aselective proteinuria.


Assuntos
Membrana Celular/metabolismo , Ativação do Complemento , Via Alternativa do Complemento , Túbulos Renais Proximais/metabolismo , Microvilosidades/metabolismo , Anafilatoxinas/biossíntese , Animais , Ligação Competitiva , Proteínas do Sistema Complemento/análise , Imunofluorescência , Secções Congeladas , Cobaias , Humanos , Imunoglobulinas/análise , Contração Muscular , Properdina/análise , Ratos , Ratos Endogâmicos Lew
15.
Thromb Haemost ; 46(3): 575-80, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7314053

RESUMO

Haematochemical, urinary and tissue parameters were examined in the elaboration of the coagulation and fibrinolysis profile in 33 cases of systemic lupus erythematosus in different stages of the disease. Coagulation abnormalities varied from hypo- to hyper-coagulability, these being often associated in the same patient, either simultaneously or at different stages of the disease. Activation of coagulation, closely related to the immunological activity of the disease, was present in 80% cases in the acute stage, and 36% of those in the remission stage. The lupus-like anticoagulant was not much involved, and platelets were the prime figures in the haemostatic abnormalities of lupus, those being the preferred target of direct antibody activities, or possibly of immune complexes as well. Activation of the coagulatory cascade is not uncommonly accompanied by a thrombophilic tendency coupled with signs of consumption, this being the expression of a continuously stimulated haemostatic balance.


Assuntos
Doenças Autoimunes/metabolismo , Coagulação Sanguínea , Lúpus Eritematoso Sistêmico/metabolismo , Autoanticorpos/isolamento & purificação , Testes de Coagulação Sanguínea , Plaquetas/fisiologia , Coagulação Intravascular Disseminada/etiologia , Fibrinólise , Hemorragia/etiologia , Humanos , Testes de Função Plaquetária , Ativador de Plasminogênio Tipo Uroquinase/urina
18.
Minerva Med ; 71(11): 835-40, 1980 Mar 24.
Artigo em Italiano | MEDLINE | ID: mdl-6103522

RESUMO

The tissue damage during the inflammation is determined by the enzymes and the mediators of anaphylaxis released from polymorphonuclear cells (PMN), platelets, basophils and mastocytes. The control of this release involves the cAMP and cGMP. The cyclic nucleotides independently or synergically regulate the polymerisation of the microtubules and the microfilaments. Drugs increasing the intracellular concentration of cAMP or cGMP inhibit or enhance respectively the enzymatic release from PMN, basophils and mastocytes. In the platelets, cAMP plays a very important role, whereas the cGMP function is controversial.


Assuntos
Adenilil Ciclases/fisiologia , AMP Cíclico/fisiologia , GMP Cíclico/fisiologia , Guanilato Ciclase/fisiologia , Inflamação/fisiopatologia , Adenilil Ciclases/metabolismo , Animais , Basófilos/metabolismo , Plaquetas/metabolismo , Cálcio/metabolismo , AMP Cíclico/biossíntese , GMP Cíclico/biossíntese , Guanilato Ciclase/metabolismo , Humanos , Inflamação/metabolismo , Mastócitos/metabolismo , Neutrófilos/metabolismo
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