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1.
Artigo em Inglês | MEDLINE | ID: mdl-18003376

RESUMO

There is a need to precisely measure concentration of proteins in biological substance for early diagnosis of disease or knowledge of fundamental biological processes. Many apparatus have been proposed, and now data processing methods have to be investigated. This paper focuses on data processing of proteomic experiments combining nano liquid chromatography and mass spectrometry. Experimental fluctuations of this process raise an interest for robust methods. Consequently, we propose a model of this acquisition system and a probabilistic Bayesian method to estimate the proteins' concentrations and system parameters.


Assuntos
Cromatografia Líquida/métodos , Perfilação da Expressão Gênica/métodos , Espectrometria de Massas/métodos , Reconhecimento Automatizado de Padrão/métodos , Mapeamento de Peptídeos/métodos , Proteoma/análise , Proteoma/química , Algoritmos , Inteligência Artificial , Teorema de Bayes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
2.
Artigo em Inglês | MEDLINE | ID: mdl-18003377

RESUMO

This paper presents a full proteomics analysis LC-MS (Liquid Chromatography-Mass Spectrometry) chain combining bio, nano and information technologies in order to quantify targeted proteins in blood sample. The objective is to enable an early detection of pancreatic cancer. We focus on the data processing step which estimates the proteins' concentration. First, we pre-process the data in order to correct time shift between the experiments. We propose to use block matching algorithm. Second, quantification of protein is performed using chemometrics approaches and more precisely CLS, PLS, N-PLS and PARAFAC algorithms. Performances of the various methods have been compared on cytochrome c protein LC-MS analyses.


Assuntos
Algoritmos , Análise Química do Sangue/métodos , Proteínas Sanguíneas/análise , Cromatografia Líquida/métodos , Técnicas de Química Combinatória/métodos , Espectrometria de Massas/métodos , Reconhecimento Automatizado de Padrão/métodos , Biomarcadores/sangue , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Gerontology ; 50(6): 393-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15477700

RESUMO

OBJECTIVES: Due to an increase in the percentage of older people in industrialized countries there is an increasing demand for medical care for the elderly. With advancing age, a series of structural, architectural and compositional modifications take place in the vasculature. Therefore, we analyzed the influence of patient age on the reocclusion rate of recanalized peripheral arteries. PATIENTS AND METHODS: 471 patients (mean age +/- SD: 62 +/- 12 years, range: 28-90 years) successfully treated by interventional recanalization were followed up (mean +/- SD: 18 +/- 17 months, range:6-48 months). Reocclusion of the recanalized arterial segment could be proven in 175 patients (37%), whereas octogenarians had the highest patency rate i.e. 68%. Univariate analysis, multivariate logistic regression analysis, and ROC analysis were performed. RESULTS: The univariate analysis showed a significant relation between reocclusion and PAOD stage, hyperlipoproteinemia, and total cholesterol level and erythrocyte sedimentation rate (ESR), respectively. Excluding age-related risk factors, the multivariate logistic regression analysis with backward selection reached a significant level for PAOD stage with p = 0.0012 and an odds ratio of 1.63, and for ESR with a p = 0.0013 and an odds ratio of only 1.02. Age did not reach a significant level with a p value of 0.13 and an odds ratio of 0.98. In the ROC analysis, prognostic relevance could be shown for the combination of PAOD stage and ESR adjusted for age and hyperlipidemia, and for PAOD stage and ESR value as a single prognostic factor, but not for patient age. CONCLUSION: Thus, despite proven and hypothetical differences in the vascular biology of older people compared to younger people, age is not related to middle term patency rates after interventional recanalization of peripheral arterial occlusions.


Assuntos
Angioplastia com Balão , Arteriopatias Oclusivas/terapia , Doenças Vasculares Periféricas/terapia , Terapia Trombolítica , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Sedimentação Sanguínea , Colesterol/sangue , Feminino , Seguimentos , Humanos , Hiperlipoproteinemias/complicações , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prognóstico , Curva ROC , Recidiva , Estudos Retrospectivos , Fatores de Risco , Trombectomia/métodos , Resultado do Tratamento
4.
Vasa ; 33(1): 52-4, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15061050
5.
J Clin Chem Clin Biochem ; 27(4): 243-4, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2738537

RESUMO

A method is described for the analysis of chromium in saliva by atomic absorption spectrometry. Cr was determined by using the Zeeman background correction, and with optimization of all the conditions of the Stabilized Temperature Platform Furnace (STPF). The low detection limit and the ability to analyse very small sample volumes make this technique especially suitable for epidemiological surveys. Also required are certified saline reference samples, representing narrow ranges of trace metals.


Assuntos
Cromo/análise , Saliva/análise , Cromo/urina , Humanos , Padrões de Referência , Espectrofotometria Atômica
6.
J Clin Chem Clin Biochem ; 27(4): 244-5, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2738538

RESUMO

Salivary calculi consist of a concentrically arranged, heterogeneous mixture of different phosphates of calcium, together with an inorganic matrix. The different crystalline phases are: hydroxyl- and carbonate-apatite, whitlockite and calcium octaphosphate. Investigation of 50 cases of sialothiasis (salivary gland disease) revealed characteristic sex-dependent differences in the uptake of toxic heavy metals by salivary calculi. The contents of fluorine and lead were positively correlated, which may be due to the fact that lead substitutes for calcium in the apatite structure of the inorganic matrix.


Assuntos
Cálculos das Glândulas Salivares/análise , Humanos , Doenças das Glândulas Salivares/metabolismo , Espectrofotometria Atômica
7.
ZWR ; 98(4): 344-8, 1989 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-2816089

RESUMO

Resulting from phase-analytical and chemical examinations there are characteristically habitual differences in the consistency of dental calculus. Very obvious are sex (gender) specific and job specific differences concerning the contents of heavy metals like lead, cadmium, copper, and zinc. Characteristics concerning the quantity, consistency and temper of dental calculus as well as the peal-homogeneous value (pH-value) of the saliva are obvious with miners working in salt-mines.


Assuntos
Cálculos Dentários/análise , Humanos , Metais/análise
8.
ZWR ; 98(3): 240-5, 1989 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-2560600

RESUMO

The efficiency of extremely small particles of hydroxylapatite on a therapy with hypersensitive tooth-necks was approved in a double-blind-study. 90% of the test persons stated an improvement of their complaints after 3-5 days, and 50% became complaintless within the time of study. The manner of working was proved with the help of x-ray inclination and by polarisation-optical studies.


Assuntos
Sensibilidade da Dentina/terapia , Hidroxiapatitas , Raiz Dentária/fisiopatologia , Método Duplo-Cego , Durapatita , Humanos
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