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1.
J Gambl Stud ; 31(1): 225-42, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23949626

RESUMO

The past decade has witnessed an expanded accessibility and popularity of gambling worldwide, and in Italy the phenomenon significantly increased. Nevertheless, little is known about the role of gambling cognitions among Italian individuals, and few scales assessing problem gambling have been validated. The purpose of the present study was to examine and validate the Gambling Related Cognitions Scale-Italian version (GRCS-I), based on the 23-item Gambling Related Cognitions Scale (GRCS). Two-tailed t tests, ANOVA, MANOVA, Pearson's correlation, and multiple regression analyses were used for continuous variables, while χ(2) tests with Yates's correction for categorical variables. Cronbach's α was utilized to determine the internal consistency, and logistic regression analysis and the receiver operating characteristic curve analysis to determine discriminant validity. Principal axis factoring with Oblimin rotation was applied, and then confirmatory factor analysis was used to cross-validate the factor structures. We extracted a five-factor solution that accounted for 60 % of variance. All 23 items had communalities and factor loadings were satisfactory, and the factor structures were similar to the original version of the measure. The Cronbach's α coefficients were adequate, and concurrent and discriminant validities of the GRCS were also confirmed. GRCS-I presented good psychometric properties and it demonstrated good validity and reliability, providing a valid and suitable tool for the assessment of gambling related cognitions among Italian individuals.


Assuntos
Comportamento Aditivo/diagnóstico , Cognição , Jogo de Azar/diagnóstico , Inquéritos e Questionários/normas , Análise de Variância , Comportamento Aditivo/psicologia , Análise Fatorial , Feminino , Jogo de Azar/psicologia , Humanos , Itália , Idioma , Masculino , Psicometria , Reprodutibilidade dos Testes
2.
Clin Chem Lab Med ; 49(4): 677-84, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21288182

RESUMO

BACKGROUND: The specificity of screening for congenital adrenal hyperplasia by direct measurement of 17-hydroxyprogesterone in filter paper dried blood spot samples by immunoassay is low and has a high false-positive rate. In order to reduce the false-positive rate of this test, we developed a rapid, robust, specific confirmatory procedure in which cortisol, 4-androstene-3,17-dione and 17-hydroxyprogesterone were measured simultaneously by ultra-performance liquid chromatography-tandem mass spectrometry. METHODS: After extraction, samples were analysed by ultra-performance liquid chromatography-tandem mass spectrometry and 17-hydroxyprogesterone was quantified accurately. Other steroids were determined using stable deuterated internal standards. In total, 25 patient blood spot samples and 92 control samples were analysed. RESULTS: The assay was linear for 17-hydroxyprogesterone, with a coefficient of determination >0.997 and imprecision ≤ 6.5%. An upper limit of normal for 17-hydroxyprogester-one of 4.45 nmol/L was established by analysing a cohort of samples from unaffected newborns. In addition, a cut-off of 3.5 for the peak areas ratio (17-hydroxyprogesterone+4-androstene-3,17-dione)/cortisol, allows confirmation of the affected steroidogenic enzyme. CONCLUSIONS: A high throughput method for the detection of steroids related to congenital adrenal hyperplasia has been developed, allowing the false-positive rate associated with screening for 17-hydroxyprogesterone by immunoassay to be determined.


Assuntos
Glândulas Suprarrenais/metabolismo , Hiperplasia Suprarrenal Congênita/sangue , Análise Química do Sangue/métodos , Coleta de Amostras Sanguíneas/métodos , Filtração/instrumentação , Papel , Esteroides/sangue , Hiperplasia Suprarrenal Congênita/diagnóstico , Cromatografia Líquida de Alta Pressão , Humanos , Controle de Qualidade , Esteroides/metabolismo , Espectrometria de Massas em Tandem
3.
Infect Immun ; 78(6): 2466-76, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20308302

RESUMO

Stenotrophomonas maltophilia is a pathogen that causes infections mainly in immunocompromised patients. Despite increased S. maltophilia isolation from respiratory specimens of patients with cystic fibrosis (CF), the real contribution of the microorganism to CF pathogenesis still needs to be clarified. The aim of the present study was to evaluate the pathogenic role of S. maltophilia in CF patients by using a model of acute respiratory infection in DBA/2 mice following a single exposure to aerosolized bacteria. The pulmonary bacterial load was stable until day 3 and then decreased significantly from day 3 through day 14, when the bacterial load became undetectable in all infected mice. Infection disseminated in most mice, although at a very low level. Severe effects (swollen lungs, large atelectasis, pleural adhesion, and hemorrhages) of lung pathology were observed on days 3, 7, and 14. The clearance of S. maltophilia observed in DBA/2 mouse lungs was clearly associated with an early and intense bronchial and alveolar inflammatory response, which is mediated primarily by neutrophils. Significantly higher levels of interleukin-1beta (IL-1beta), IL-6, IL-12, gamma interferon (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), GROalpha/KC, MCP-1/JE, MCP-5, macrophage inflammatory protein 1alpha (MIP-1alpha), MIP-2, and TARC were observed in infected mice on day 1 with respect to controls. Excessive pulmonary infection and inflammation caused systemic effects, manifested by weight loss, and finally caused a high mortality rate. Taken together, our results show that S. maltophilia is not just a bystander in CF patients but has the potential to contribute to the inflammatory process that compromises respiratory function.


Assuntos
Fibrose Cística/microbiologia , Fibrose Cística/patologia , Inflamação , Pulmão/microbiologia , Pulmão/patologia , Stenotrophomonas maltophilia/imunologia , Stenotrophomonas maltophilia/patogenicidade , Animais , Peso Corporal , Contagem de Colônia Microbiana , Fibrose Cística/imunologia , Fibrose Cística/mortalidade , Citocinas/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos DBA , Neutrófilos/imunologia , Análise de Sobrevida
4.
Bioinformatics ; 24(1): 63-70, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18003646

RESUMO

MOTIVATION: Independent component analysis (ICA) is a signal processing technique that can be utilized to recover independent signals from a set of their linear mixtures. We propose ICA for the analysis of signals obtained from large proteomics investigations such as clinical multi-subject studies based on MALDI-TOF MS profiling. The method is validated on simulated and experimental data for demonstrating its capability of correctly extracting protein profiles from MALDI-TOF mass spectra. RESULTS: The comparison on peak detection with an open-source and two commercial methods shows its superior reliability in reducing the false discovery rate of protein peak masses. Moreover, the integration of ICA and statistical tests for detecting the differences in peak intensities between experimental groups allows to identify protein peaks that could be indicators of a diseased state. This data-driven approach demonstrates to be a promising tool for biomarker-discovery studies based on MALDI-TOF MS technology. AVAILABILITY: The MATLAB implementation of the method described in the article and both simulated and experimental data are freely available at http://www.unich.it/proteomica/bioinf/.


Assuntos
Reconhecimento Automatizado de Padrão/métodos , Mapeamento de Peptídeos/métodos , Proteoma/química , Análise de Sequência de Proteína/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Algoritmos , Sequência de Aminoácidos , Dados de Sequência Molecular , Análise de Componente Principal , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
BMC Bioinformatics ; 8: 101, 2007 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-17386085

RESUMO

BACKGROUND: Mass spectrometry protein profiling is a promising tool for biomarker discovery in clinical proteomics. However, the development of a reliable approach for the separation of protein signals from noise is required. In this paper, LIMPIC, a computational method for the detection of protein peaks from linear-mode MALDI-TOF data is proposed. LIMPIC is based on novel techniques for background noise reduction and baseline removal. Peak detection is performed considering the presence of a non-homogeneous noise level in the mass spectrum. A comparison of the peaks collected from multiple spectra is used to classify them on the basis of a detection rate parameter, and hence to separate the protein signals from other disturbances. RESULTS: LIMPIC preprocessing proves to be superior than other classical preprocessing techniques, allowing for a reliable decomposition of the background noise and the baseline drift from the MALDI-TOF mass spectra. It provides lower coefficient of variation associated with the peak intensity, improving the reliability of the information that can be extracted from single spectra. Our results show that LIMPIC peak-picking is effective even in low protein concentration regimes. The analytical comparison with commercial and freeware peak-picking algorithms demonstrates its superior performances in terms of sensitivity and specificity, both on in-vitro purified protein samples and human plasma samples. CONCLUSION: The quantitative information on the peak intensity extracted with LIMPIC could be used for the recognition of significant protein profiles by means of advanced statistic tools: LIMPIC might be valuable in the perspective of biomarker discovery.


Assuntos
Biologia Computacional/métodos , Proteínas/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Adulto , Biologia Computacional/instrumentação , Biologia Computacional/normas , Eletricidade/efeitos adversos , Humanos , Proteômica/instrumentação , Proteômica/métodos , Proteômica/normas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/normas
6.
Clin Chim Acta ; 357(2): 210-8, 2005 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-15913587

RESUMO

BACKGROUND: The development of MALDI Imaging Mass Spectrometry is a promising technique in the investigation of biological molecular repertoire. We have pursued an analytical assessment of this technique in its application to proteome analysis. METHODS: A specific statistical method of analysis has been developed to enable data processing in the absence of internal standards, by defining similarity scores. RESULTS: The investigated linear mode MALDI-TOF set-up allows to obtain data variations comprised within the 30% of variation when assaying tissues samples from the same animal, while the 60% of variation was highlighted in the inter-mice series assaying syngenic animals. CONCLUSIONS: This analytical assessment represents the first step of a process that should validate the utilisation of this technique in the clinical practice.


Assuntos
Histocitoquímica/métodos , Proteoma/química , Proteoma/metabolismo , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Modelos Lineares , Masculino , Camundongos , Camundongos Transgênicos , Neoplasias da Próstata/metabolismo , Reprodutibilidade dos Testes , Neoplasias das Glândulas Salivares/metabolismo
7.
Org Lett ; 6(10): 1633-5, 2004 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15128254

RESUMO

Two new steroidal derivatives, named clionastatins A and B, have been isolated from the burrowing sponge Cliona nigricans. These molecules are tri-and tetrachlorinated androstane derivatives, respectively, and they represent the first polyhalogenated steroids found in a natural organism, either marine or terrestrial, and the first examples of halogenated androstanes in nature. Both clionastatins proved to be potently cytotoxic.


Assuntos
Androstanos/isolamento & purificação , Poríferos/química , Androstanos/química , Animais , Conformação Molecular
8.
J Agric Food Chem ; 51(24): 6970-4, 2003 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-14611156

RESUMO

Three new diterpenoids belonging to the clerodane (2-3) and halimane (4) structural types have been isolated from the bark of Croton eluteria Bennet, commonly known as cascarilla. Their structures have been fully characterized by spectroscopic means. Cascarilla extract and its major component, cascarillin, were found to significantly increase histamine-induced gastric acid secretion in the mouse stomach. These preliminary results provide the first rationale for the use of cascarilla in bitter preparations aimed at improving digestion.


Assuntos
Croton/química , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Ácido Gástrico/metabolismo , Extratos Vegetais/química , Animais , Diterpenos/química , Histamina/farmacologia , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos ICR
9.
J Proteomics ; 74(12): 2826-36, 2011 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-21757039

RESUMO

Multiple Sclerosis (MS) is a neurodegenerative autoimmune demyelinating disease affecting young adults. The aetiology still remains a mystery and diagnosis is impaired by the lack of defined molecular markers. Autoimmune response remains the main topic under investigation and recent studies suggest additional non-proteic mediators of brain inflammation such as lipids. We carried out an LC-MS based lipidomics approach to highlight serum lipids profiling in MS. Method was optimised and applied in a preliminary clinical cross-sectional investigation of MS patients vs Healthy Controls (HC) and patients with Other Neurological Diseases (OND). Ten significant metabolites were highlighted and tentatively identified by accurate mass and MS/MS experiments. Our most relevant data show altered level of lyso-glycerophosphatidylcholine (lysoPC) and glycerophosphatidylcholine (PC) species. Total lysoPC/PC ratio showed significant decrease in pathological groups (MS, OND) and, in addition, MS subjects had a relevant decrease of this ratio also in respect to OND. These findings suggest that there may be an altered phospholipid metabolism in MS that can be evaluated in serum. Some of these features are distinctive and may be considered specific for MS. Our lipidomics data show, for the first time, evidence in serum of a relationship between LysoPC/PC ratio and MS.


Assuntos
Metabolismo dos Lipídeos , Lisofosfatidilcolinas/sangue , Esclerose Múltipla/sangue , Adolescente , Adulto , Feminino , Humanos , Masculino , Espectrometria de Massas/métodos , Pessoa de Meia-Idade
10.
J Proteomics ; 73(3): 562-70, 2010 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-19914411

RESUMO

BACKGROUND: Mass spectrometry (MS) is becoming the gold standard for biomarker discovery. Several MS-based bioinformatics methods have been proposed for this application, but the divergence of the findings by different research groups on the same MS data suggests that the definition of a reliable method has not been achieved yet. In this work, we propose an integrated software platform, MASCAP, intended for comparative biomarker detection from MALDI-TOF MS data. RESULTS: MASCAP integrates denoising and feature extraction algorithms, which have already shown to provide consistent peaks across mass spectra; furthermore, it relies on statistical analysis and graphical tools to compare the results between groups. The effectiveness in mass spectrum processing is demonstrated using MALDI-TOF data, as well as SELDI-TOF data. The usefulness in detecting potential protein biomarkers is shown comparing MALDI-TOF mass spectra collected from serum and plasma samples belonging to the same clinical population. CONCLUSIONS: The analysis approach implemented in MASCAP may simplify biomarker detection, by assisting the recognition of proteomic expression signatures of the disease. A MATLAB implementation of the software and the data used for its validation are available at http://www.unich.it/proteomica/bioinf.


Assuntos
Análise Química do Sangue/estatística & dados numéricos , Biologia Computacional/métodos , Plasma/química , Soro/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Algoritmos , Doenças Autoimunes/sangue , Doenças Autoimunes/metabolismo , Biomarcadores/análise , Biomarcadores/sangue , Biomarcadores/metabolismo , Análise Química do Sangue/métodos , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/metabolismo , Análise por Conglomerados , Interpretação Estatística de Dados , Humanos , Plasma/metabolismo , Soro/metabolismo
11.
J Proteomics ; 73(3): 579-92, 2010 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-19666151

RESUMO

Serum proteome investigations have raised an incredible interest in the research of novel molecular biomarker, nevertheless few of the proposed evidences have been translated to the clinical practice. One of the limiting factors has been the lack of generally accepted guidelines for clinical proteomics studies and the lack of a robust analytical and pre-analytical ground for the proposed classification models. Pre-analytical issues may results in a deep impact for biomarker discovery campaign. In this study we present a systematic evaluation of sample storage and sampling conditions for clinical proteomics investigations. We have developed and validated a linear MALDI-TOF-MS protein profiling method to explore the low protein molecular weight region (5-20 kDa) of serum samples. Data normalization and processing was performed using optimise peak detection routine (LIMPIC) able to describe each group under investigation. Data were acquired either from healthy volunteers and from multiple sclerosis patients in order to highlight ex vivo protein profile alteration related to different physio-pathological conditions. Our data showed critical conditions for serum protein profiles depending on storage times and temperatures: 23 degrees C, 4 degrees C, -20 degrees C and -80 degrees C. We demonstrated that upon a -20 degrees C short term storage, characteristic degradation profiles are associated with different clinical groups. Protein signals were further identified after preparative HPLC separation by peptide sequencing on a nanoLC-Q-TOF TANDEM mass spectrometer. Apolipoprotein A-IV and complement C3 protein fragments, transthyretin and the oxidized isoforms in different apolipoprotein species represent the major molecular features of such a degradation pattern.


Assuntos
Biomarcadores/análise , Biomarcadores/sangue , Esclerose Múltipla/sangue , Processamento de Proteína Pós-Traducional/fisiologia , Proteômica/normas , Adolescente , Adulto , Algoritmos , Biomarcadores/metabolismo , Preservação de Sangue/efeitos adversos , Preservação de Sangue/métodos , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/metabolismo , Fatores de Confusão Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/metabolismo , Projetos Piloto , Estabilidade Proteica , Proteômica/métodos , Proteômica/estatística & dados numéricos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/normas , Adulto Jovem
12.
J Proteome Res ; 8(9): 4383-91, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19585971

RESUMO

In the last years, proteomic investigation provided a powerful tool in molecular characterization of complex allergen sources with relevant implications in both diagnosis and immunotherapic treatment of allergies. We followed a proteomic approach to characterize ryegrass (Lolium perenne) pollen, a common cause of seasonal allergic diseases affecting an increasing part of world population. Peptide shotgun experiments performed on nanoLiquid Ultra Pressure Chromatography coupled with fast Q-TOF MS-MS/MS acquisition protocols (MS(E)) and 2-DE immunoblot combined with MALDI-TOF-TOF analysis allowed the detection of all previously identified ryegrass allergens. Comparative analysis of immunoblot highlighted a class of patients characterized by a more complex 2-DE pattern associated with increased levels of IgE antibodies and by higher susceptibility to multiple sensitization toward different allergen sources. Cluster analysis revealed that all these patients recognized profilin, considered the main cross-reactive allergen in grass pollen. Furthermore, mass spectrometry analysis revealed the presence of other IgE reactive components in ryegrass pollen that might be involved in polysensitization, such as cyclophilin, fructosyltransferase and legumin-like protein.


Assuntos
Imunoglobulina E/imunologia , Lolium/imunologia , Pólen/imunologia , Proteômica/métodos , Rinite Alérgica Sazonal/imunologia , Análise por Conglomerados , Estudos de Coortes , Eletroforese em Gel Bidimensional , Humanos , Immunoblotting , Imunoglobulina E/química , Imunoglobulina E/metabolismo , Lolium/química , Análise Multivariada , Pólen/química , Pólen/metabolismo , Rinite Alérgica Sazonal/metabolismo , Estatísticas não Paramétricas
13.
Bioorg Med Chem ; 13(13): 4238-42, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15878280

RESUMO

Investigation of the bark of Croton eluteria Bennett for biologically active compounds has led to the isolation of the new prenylbisabolane 3, whose structure was assessed by spectroscopic methods. The corresponding known enone 4 and the eudesmane sesquiterpene 2 were also obtained. Compound 3 proved active in selectively inhibiting the induction of NF-kappaB by tumor necrosis factor-alpha in T cells.


Assuntos
Croton/química , Diterpenos/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Extratos Vegetais/metabolismo , Sesquiterpenos/metabolismo , Ciclo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Diterpenos/química , Diterpenos/isolamento & purificação , Repetição Terminal Longa de HIV/genética , Humanos , Luciferases/metabolismo , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
14.
J Nat Prod ; 68(6): 853-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15974607

RESUMO

Chemical investigation of Santolina insularis afforded 11 germacrane sesquiterpenes (1-11), four of which (2, 3, 10, and 11) are new. The stereostructures of these compounds have been established by a combination of spectroscopic techniques (mainly NMR), chemical transformations, and application of the modified Mosher method. Compounds 8 and 10 showed a potent and selective cytotoxic activity against the human colon carcinoma cell line.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Asteraceae/química , Plantas Medicinais/química , Sesquiterpenos de Germacrano/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Itália , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos de Germacrano/química , Sesquiterpenos de Germacrano/farmacologia , Estereoisomerismo
15.
Planta Med ; 71(10): 928-32, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16254824

RESUMO

A bioassay-guided separation of a methanolic extract obtained from the roots of Boerhaavia diffusa L. (Nyctaginaceae) allowed us to isolate five compounds belonging to the class of rotenoids: the known boeravinone D ( 1), boeravinone E ( 2), compound 5 and two novel compounds that we have named boeravinone G ( 3) and boeravinone H ( 4). The structures of the new molecules have been determined on the basis of their HR-EI-MS, (1)H- and (13)C-NMR and 2D-NMR (HMQC, HMBC) data. All the isolated rotenoids have been evaluated for their effect on intestinal motility in vitro. Three of them (boeravinone G, boeravinone E and compound 5) exhibited spasmolytic activity. Preliminary structure-activity relationships have been established highlighting the effect of substitutions on rings B and D.


Assuntos
Motilidade Gastrointestinal/efeitos dos fármacos , Nyctaginaceae , Parassimpatolíticos/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Relação Dose-Resposta a Droga , Cobaias , Masculino , Parassimpatolíticos/administração & dosagem , Parassimpatolíticos/uso terapêutico , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Raízes de Plantas
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