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E Valadas

Publications and source records attributed to E Valadas.

10 recordsLinked to original sources
PubMed2003

Smear microscopy to diagnose tuberculosis early and prevent further transmission in a population with a high prevalence of HIV infection.

In western Europe, Portugal has the highest incidence of tuberculosis (TB). The quickest way to diagnose TB is with a positive smear. To evaluate the usefulness of smear microscopy in a population with a high HIV seroprevalence, TB patients admitted during the year 2000 were retrospectively analyzed. Of the 74 TB patients admitted, 45 (61%) had pulmonary TB, 11 having multiresistant (MR)-TB. Considering that only half of the patients with pulmonary TB had a positive smear, a high degree of clinical suspicion is of great importance. Appropriate isolation facilities for TB are much needed, in order to prevent nosocomial TB spread.

Adolescent↗
PubMed2000

Automated malaria diagnosis using pigment detection.

Several new methods of malaria diagnosis have recently been developed, but these all rely on clinical suspicion and, consequently, an explicit clinical request. Although some methods lend themselves to automation (eg. PCR), no technique can yet be used for routine clinical automated screening. Detection of birefringent haemozoin has been used to diagnose malaria since the turn of the 20th century. A new generation of full blood count analysers, used widely in clinical laboratories, have the potential to detect haemozoin in white blood cells and probably erythrocytes. Thomas Hänscheid, Emilia Valadas and Martin Grobusch here describe this novel technique for malaria diagnosis and discuss its potential applications.

Blood Cell Count↗
PubMed2000

Monocyte-derived macrophage cytokine responses induced by M. bovis BCG.

SETTING: One important aspect of macrophage function is the production of inflammatory and anti-inflammatory cytokines, which in turn affect the survival of intracellular organisms such as mycobacteria. OBJECTIVE: To determine the relationship between phagocytosis of mycobacteria and expression of intracellular cytokines. DESIGN: Phagocytosis and cytokine production were studied simultaneously within human monocyte-derived macrophages (MDMs) from healthy donors using fluorescent labelling of M. bovis BCG and flow cytometry. RESULTS: At a range of infection ratios (5:1, 1:1, 0.2:1) TNF- alpha, IL-10, IL-6 and IL-12 were all produced in a dose-dependent manner. At an infection ratio representative of the in vivo situation (1:1), cytokine production was induced in both MDMs containing intracellular M. bovis BCG and in uninfected bystander MDMs. Phagocytosis increased over time, but there was considerable donor variation: the proportions of cells containing one or more mycobacterium were 15.4+/-14.8% (mean+/-SD) at 4 h and 32.7+/-21.1% at 24 h (n=19). Analysis of cytokine production by MDMs not containing mycobacteria (bystander cells) at 4 h revealed that these uninfected cells produced 79+/-6.6% of the TNF- alpha, 53.9+/-40.0% of the IL-10 and 64.2+/-12.4% of the IL-12. By 20 h these proportions had decreased to 57+/-13.5%, 30.9+/-7.4% and 45.5+/-13.3% respectively. CONCLUSION: Both infected and bystander MDMs can be stimulated to produce cytokines in response to M. bovis BCG, indicating that the ability of MDMs to produce cytokines is not necessarily dependent on the ability to phagocytose mycobacteria.

Adult↗
PubMed1999

Usefulness of immunochromatographic detection of antibodies to Mycobacterium tuberculosis as an adjunct to auramine staining for rapid diagnosis of tuberculosis in a low-prevalence setting.

A novel immunochromatographic membrane-based assay for the detection of specific IgG antibodies to Mycobacterium tuberculosis was evaluated in patients with active tuberculosis in a low-prevalence population. The sensitivity of the test for detecting active tuberculosis was 41.5% (17/41 patients positive); its specificity in a group of patients with other lung diseases was 91.4% (3/35 false positive), while in a group of 47 healthy controls it was 100%. The sensitivity of the immunochromatographic test equaled that of auramine staining, but different subsets of tuberculosis patients were detected by the two tests. The suboptimal sensitivity of this immunochromatographic test implies that, even though it could be a useful adjunct, it cannot be a replacement for the diagnosis of tuberculosis by other microbiological methods along with clinical and radiological data.

Antibodies, Bacterial↗
PubMed1999

Malaria diagnosis.

Explore the source record for details and available documents.

Diagnostic Techniques and Procedures↗
PubMed1995

[Neurosyphilis and AIDS].

Syphilis in HIV-infected patients reveals some particular aspects which are clinically relevant and disturbing: it is more frequent and develops more quickly to late stages, namely neurosyphilis; this progression may happen even if classic therapy in the early stages has been undertaken; the diagnosis of neurosyphilis is rather complex, the serological tests being of no definite credit; high doses of intravenous penicillin should be administered for a long period. We report a case that exemplifies the aspects described above.

AIDS-Related Opportunistic Infections↗