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1.
Int J Tuberc Lung Dis ; 17(5): 682-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23575336

RESUMO

BACKGROUND: Clinicians in countries with high tuberculosis (TB) prevalence often treat pleural TB based on clinical grounds, as the availability and sensitivity of diagnostic tests are poor. OBJECTIVE: To evaluate the role of artificial neural networks (ANN) as an aid for the non-invasive diagnosis of pleural TB. These tools can be used in simple computer devices (tablets) without remote internet connection. METHODS: The clinical history and human immunodeficiency virus (HIV) status of 137 patients were prospectively entered in a database. Both non-linear ANN and the linear Fisher discriminant were used to calculate performance indexes based on clinical grounds. The same procedure was performed including pleural fluid test results (smear, culture, adenosine deaminase, serology and nucleic acid amplification test). The gold standard was any positive test for TB. RESULTS: In pre-test modelling, the neural model reached >90% accuracy (Fisher discriminant 74.5%). Under pre-test conditions, ANN had better accuracy compared to each test considered separately. CONCLUSIONS: ANN are highly reliable for diagnosing pleural TB based on clinical grounds and HIV status only, and are useful even in remote conditions lacking access to sophisticated medical or computer infrastructure. In other better-equipped scenarios, these tools should be evaluated as substitutes for thoracocentesis and pleural biopsy.


Assuntos
Diagnóstico por Computador , Redes Neurais de Computação , Tuberculose Pleural/diagnóstico , Adulto , Técnicas Bacteriológicas , Biópsia , Coinfecção , Análise Discriminante , Progressão da Doença , Diagnóstico Precoce , Infecções por HIV/diagnóstico , Humanos , Modelos Lineares , Mycobacterium tuberculosis/isolamento & purificação , Dinâmica não Linear , Paracentese , Derrame Pleural/microbiologia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Tuberculose Pleural/microbiologia
2.
Epidemiol Infect ; 141(11): 2286-93, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23419686

RESUMO

This study was conducted to determine the seroprevalence of anti-Neospora caninum antibodies and to investigate the risk factors related to seroprevalence in dogs from urban and rural areas with distinct economic activities (milk and coffee production) in Minas Gerais state, Brazil. For this purpose, blood samples from 703 dogs were collected and questionnaires addressing epidemiological aspects were completed by dog-owners. The sera were analysed for anti-N. caninum antibodies by indirect fluorescent antibody tests (IFAT ≥ 1:50). Association between epidemiological aspects and seropositivity in dogs was evaluated with multivariate logistic regression models. A total of 80 (11·4%) dogs tested positive for N. caninum. In the multivariate logistic regression models, dogs aged >4 years, dogs used as guard dogs, dogs that spontaneously hunt, and history of bovine abortion were found to be greater risk factors for canine N. caninum infection. When we considered only dogs from rural areas, an association with seroprevalence was seen for milk farms, dogs not fed with commercial food, dogs that hunt, and dogs used as guard dogs.


Assuntos
Coccidiose/veterinária , Coffea , Doenças do Cão/parasitologia , Leite , Neospora/isolamento & purificação , Envelhecimento , Agricultura , Animais , Brasil/epidemiologia , Bovinos , Coccidiose/epidemiologia , Coccidiose/parasitologia , Doenças do Cão/epidemiologia , Cães , Técnica Indireta de Fluorescência para Anticorpo , Modelos Logísticos , Análise Multivariada , Razão de Chances , Risco , Fatores de Risco , População Rural , Estudos Soroepidemiológicos , Inquéritos e Questionários , População Urbana
3.
J Inorg Biochem ; 117: 285-91, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22883959

RESUMO

Complexes of the general formula fac-[Ru(CO)(3)L(3)](2+), namely CORM-2 and CORM-3, have been successfully used as experimental CO releasing molecules (CO-RMs) but their mechanism of action and delivery of CO remain unclear. The well characterized complex [Ru(CO)(3)Cl(2)(1,3-thiazole)] (1) is now studied as a potential model CO-RM of the same family of complexes using LC-MS, FTIR, and UV-vis spectroscopy, together with X-ray crystallography. The chemistry of [Ru(CO)(3)Cl(2)(1,3-thiazole)] is very similar to that of CORM-3: it only releases residual amounts of CO to the headspace of a solution in PBS7.4 and produces marginal increase of COHb after long incubation in whole blood. 1 also reacts with lysozyme to form Ru adducts. The crystallographic model of the lysozyme-Ru adducts shows only mono-carbonyl Ru species. [Ru(H(2)O)(4)(CO)] is found covalently bound to a histidine (His15) and to two aspartates (Asp18 and Asp119) at the protein surface. The CO release silence of both 1 and CORM-3 and their rapid formation of protein-Ru(CO)(x)(H(2)O)(y) (x=1,2) adducts, support our hypothesis that fac-[Ru(CO)(3)L(3)] CO-RMs deliver CO in vivo through the decay of their adducts with plasma proteins.


Assuntos
Monóxido de Carbono/química , Muramidase/química , Compostos Organometálicos/química , Rutênio/química , Cristalografia por Raios X , Soluções
5.
Euro Surveill ; 16(37)2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21944556

RESUMO

A study of aggregate data collected from the literature and official sources was undertaken to estimate expected and observed prevalence of Trypanosoma cruzi infection, annual incidence of congenital transmission and rate of underdiagnosis of Chagas disease among Latin American migrants in the nine European countries with the highest prevalence of Chagas disease. Formal and informal data sources were used to estimate the population from endemic countries resident in Europe in 2009, diagnosed cases of Chagas disease and births from mothers originating from endemic countries. By 2009, 4,290 cases had been diagnosed in Europe, compared with an estimated 68,000 to 122,000 expected cases. The expected prevalence was very high in undocumented migrants (on average 45% of total expected cases) while the observed prevalence rate was 1.3 cases per 1,000 resident migrants from endemic countries. An estimated 20 to 183 babies with congenital Chagas disease are born annually in the study countries. The annual incidence rate of congenital transmission per 1,000 pregnancies in women from endemic countries was between none and three cases. The index of under diagnosis of T. cruzi infection was between 94% and 96%. Chagas disease is a public health challenge in the studied European countries. Urgent measures need to be taken to detect new cases of congenital transmission and take care of the existing cases with a focus on migrants without legal residency permit and potential difficulty accessing care.


Assuntos
Doença de Chagas/epidemiologia , Emigrantes e Imigrantes/estatística & dados numéricos , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Vigilância da População/métodos , Trypanosoma cruzi/isolamento & purificação , Doença de Chagas/prevenção & controle , Doença de Chagas/transmissão , Coleta de Dados , Ensaio de Imunoadsorção Enzimática , Estudos Epidemiológicos , Europa (Continente)/epidemiologia , Feminino , Humanos , Incidência , América Latina/etnologia , Masculino , Prevalência , Fatores de Risco , Trypanosoma cruzi/imunologia
6.
Curr Med Chem ; 18(22): 3361-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21728965

RESUMO

The biological role of carbon monoxide (CO) has completely changed in the last decade. Beyond its widely feared toxicity, CO has revealed a very important biological activity as a signaling molecule with marked protective actions namely against inflammation, apoptosis and endothelial oxidative damage. Its direct use as a therapeutic gas showed significant and consistent positive results but also intrinsic severe limitations. The possibility of replacing the gas by pro-drugs acting as CO-Releasing Molecules (CO-RMs) has clearly been demonstrated with several experimental compounds. Transition metal carbonyls complexes have proven to be the most versatile experimental CO-RMs so far. Presently, the challenge is to equip them with drug-like properties to turn them into useful pharmaceuticals. This requires studying their interactions with biological molecules namely those that control their pharmacokinetic and ADME profiles like the plasma proteins. In this account we analyze these questions and review the existing interactions between Metal Carbonyls and proteins. The recently explored case of CORM-3 is revisited to exemplify the methodologies involved and the importance of the results for the understanding of the mode of action of such pro-drugs.


Assuntos
Proteínas Sanguíneas/metabolismo , Monóxido de Carbono/uso terapêutico , Compostos Organometálicos/uso terapêutico , Monóxido de Carbono/administração & dosagem , Cardiotônicos , Humanos , Ligação Proteica
8.
Phys Rev Lett ; 100(2): 022302, 2008 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-18232858

RESUMO

The NA60 experiment at the CERN SPS has studied low-mass dimuon production in 158A GeV In-In collisions. An excess of pairs above the known meson decays has been reported before. We now present precision results on the associated transverse momentum spectra. The slope parameter Teff extracted from the spectra rises with dimuon mass up to the rho, followed by a sudden decline above. While the initial rise is consistent with the expectations for radial flow of a hadronic decay source, the decline signals a transition to an emission source with much smaller flow. This may well represent the first direct evidence for thermal radiation of partonic origin in nuclear collisions.

9.
Phys Rev Lett ; 99(13): 132302, 2007 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-17930580

RESUMO

The NA60 experiment studies muon pair production at the CERN Super Proton Synchrotron. In this Letter we report on a precision measurement of J/psi in In-In collisions. We have studied the J/psi centrality distribution, and we have compared it with the one expected if absorption in cold nuclear matter were the only active suppression mechanism. For collisions involving more than approximately 80 participant nucleons, we find that an extra suppression is present. This result is in qualitative agreement with previous Pb-Pb measurements by the NA50 experiment, but no theoretical explanation is presently able to coherently describe both results.

10.
Phys Rev Lett ; 96(16): 162302, 2006 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-16712218

RESUMO

We report on a precision measurement of low-mass muon pairs in 158 AGeV indium-indium collisions at the CERN SPS. A significant excess of pairs is observed above the yield expected from neutral meson decays. The unprecedented sample size of 360,000 dimuons and the good mass resolution of about 2% allow us to isolate the excess by subtraction of the decay sources. The shape of the resulting mass spectrum is consistent with a dominant contribution from pi+pi- -->rho -->mu+mu- annihilation. The associated space-time averaged spectral function shows a strong broadening, but essentially no shift in mass. This may rule out theoretical models linking hadron masses directly to the chiral condensate.

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