Digital disease detection and participatory surveillance: overview and perspectives for Brazil

ABSTRACT This study aimed to describe the digital disease detection and participatory surveillance in different countries. The systems or platforms consolidated in the scientific field were analyzed by describing the strategy, type of data source, main objectives, and manner of interaction with users. Eleven systems or platforms, developed from 1996 to 2016, were analyzed. There was a higher frequency of data mining on the web and active crowdsourcing as well as a trend in the use of mobile applications. It is important to provoke debate in the academia and health services for the evolution of methods and insights into participatory surveillance in the digital age.

Jamming detection in GNSS signals using the sample covariance matrix.

We propose a blind method to detect interference in GNSS signals whereby the algorithms do not require knowledge of the interference or channel noise features. A sample covariance matrix is constructed from the received signal and its eigenvalues are computed. The generalized likelihood ratio test (GLRT) and the condition number test (CNT) are developed and compared in the detection of sinusoidal and chirp jamming signals. A computationally-efficient decision threshold was proposed for the CNT.

Immunodiagnostic confirmation of hydatid disease in patients with a presumptive diagnosis of infection

Information obtained from the routine application of hydatid immunodiagnostic techniques in different clinical situations over a seven-year period is presented. The Immunoelectrophoresis test was used until it was replaced by the simpler, more sensitive and equally specific arc 5 double diffusion (DD5) test. Examination of sera from 1,888 patients with signs and/or symptoms compatible with hydatid disease revealed that the presurgical confirmation of Echinococcus granulosus infection is only obtained by detection of anti-antigen 5 antibodies. The latter were not found in 1,539 presumptive hydatidosis patients whose definitive diagnoses corresponded to other disease conditions. However, false positive latex agglutination test results were obtained in two cases. In all patients whose preoperative serum showed three or more uncharacteristic bands in the absence of anti-antigen 5 antibodies, hydatid cysts were found sur gically. DD5 testing of a fluid sample collected by puncture established its hydatid etiology. Post-operative monitoring of hydatidosis patients demonstrated that persistence of DD5-positivity two years after surgery established the presence of other cysts. Further evidence was obtained in patients with hydatid cysts in intrathoracic, abdominal or other locations associating cyst membrane integrity, antigen release and immunodiagnostic test positivity.

Land use / land cover change detection: an object oriented approach, Münster, Germany

Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies

Detection of classic and invasive E. coli and Shigella serotypes in stools by indirect immunofluorescence

IIF in the detection of invasive and classic enteropathogenic E. coli and Shigella serotypes was compared with traditional coproculture methods. IIP results agreed with the coproculture findings in 128 out of 140 cases tested for enteropathogenic E. coli (91%) and in 108 out of 112 for Shigella (96%). All cases with positive reactions by coproculture were confirmed by IIP. In the control group it were obtained by IIF 12 cases with positive reactions for enteropathogenic E. coli and 4 cases for Shigella, including two cases of mixed infection by E. coli 026/Sh. dysenteriae and E. coli 0124/Sh. dysenteriae. It was discussed the high sensitivity and specificity of the IIF when compared with the traditional methods, being suggested that IIF is a valuable tool in epidemiological studies involving these organisms and an important aid in the stablishment of an early presumptive diagnosis of the acute infantile diarrhea.

Automatic sleep apnea detection and sleep classification using the ECG and the SpO2 signals

Dissertation for a Masters Degree in Computer and Electronic Engineering

Detection of Astrovirus-like in diarrhoeic stool and its coexistence with Rotavirus

A clinical case is described in this paper in that a 5-month old baby girl severely malnourished and dehydrated presented a prolonged acute diarrhoea. No enteropathogenic bacteria or parasites were demonstrated. Virological study by electron microscopy (EM) showed that the patient shed both astrovirus-like and rotavirus in the watery stool as long as 12 days after the onset. Immune electron microscopy (IEM) performed with the patient serum revealed clumps of both viruses. It is suggest that this may be a case of mixed infection due to astrovirus-like and rotavirus.

Acute Hepatitis B in a patient previously positive for antibody to surface antigen (anti-HBs) determined by radioimmunoassay: case report and review of the literature

The determination of anti-HBs as a screening test before vaccination has been advisable in order to encounter immune individuals that don't need to receive vaccine protection. A case-report is presented and three other cases are reviewed from the literature. Anti-HBs was positive in these health-care personnels that developped typical acute B hepatitis. Different subtyping involving the d/y determinants were found in the first case, but false-positive anti-HBs even with high titres, determined by RIA, were found in the other cases. Concomitant determination of anti-HBc or absence of screening tests seem to be more reasonable policies until a low-cost and risk-free vaccine is produced.

Antigen characterization of vector-borne and cultured metacyclic trypomastigotes of Trypanosoma cruzi

Metacyclic trypomastigotes ol the CL strain of Trypanosoma cruzi obtained from triatomid vectors and from axenic cultures were comparatively analysed as to their antigen make-up and immunogenic characteristics. They were found to be similar by the various parameters examined. Thus, sera of mice immunized with either one of the two metacyclic types precipitated a 82Kd surface protein from 131I-labeled culture metacyclics. Sera of mice protected against acute T. cruzi infection by immunization with killed culture metacyclics of a different strain (G) recognized, by immunoblotting, a 77Kd protein in both types of CL strain metacyclics. A monoclonal antibody raised against G strain metacyclics, and specific for metacyclic stages of this strain, reacted with both CL strain metacyclic types. Both metacyclic forms were similarly Iysed by various anti-T. cruzi sera, in a complement-mediated reaction.

Specific circulating immune complexes in acute chagas' disease

The presence of circulating immune complexes formed by IgM and IgG (CIC-IgM and CIC-IgG) was investigated, using antigen-specific enzyme-immunoassays (ELISA), in 30 patients with acute Chagas' disease who showed parasitemia and inoculation chagoma. Control population consisted of patients with chronic T. cruzi infection (30), acute toxoplasmosis 10), leishmaniasis (8), rheumatoid arthritis (3) and healthy individuals with negative serology for Chagas* disease (30). Acute chagasic patients were 100% CIC-IgG and 96.66% CIC-IgM positive whereas immunofluorescence tests yielded 90% and 86.66% of positivity for specific IgG and IgM antibodies, respectively. Chronic patients were 68% CIC-IgG and 0% CIC-IgM positive. The 30 negative and the 21 cross-reaction controls proved negative for ELISA (CIC-IgM and CIC-IgG). The high sensitivity of ELISA assays would allow early immunologic diagnosis, as well as prompt treatment, of acute T. cruzi infection, thus eliminating the problem of the false-positive and false-negative results which affects traditional methods for detection of circulating antibodies.

Immunoperoxidase technique in experimental chronic chagasic myocarditis

Chagas'disease has been described as the commonest form of chronic myocarditis. An immunologic pathogenesis has been discribed for this form of the disease. So far, no immunoperoxidase technique has been used for the detection of immunological deposits in chronic experimental Chagas'myocardiopathy. Forty-one Swiss mice, three months old were inoculated intraperitoneally with doses between 10 and 10(5) Tulahuen trypomastigotes. Mice were reinoculated one month after with doses between 10² and 10(5) and sacrificed at 6 (n=21) and 9 months (n=9) after the first inoculation. ECGs were recorded before sacrifice. Immunoperoxidase technique (peroxidase-antiperoxidase method), immunofluorescence (direct and indirect) as well as histological studies were performed in myocardiums and skeletal muscles of the surviving animals. The most sensitive methods for detecting chronic chagasic infection were the routine histologic studies (73%) and the ECGs 83% and 89% on 6 and 9 mo. post-infected mice, respectively. Myocardial involvement varied from interstitial mild focal lymphocyte infiltrates up to replacement of myocytes by loose connective tissue. Atrial myocardiums (21/23, 91%) were more affected than ventricles (9/23, 39%). Typical chagasic nests were rarely found. Skeletal muscle involvement (11/18 and 7/9) varied from mild to extensive lymphocyte and plasmacell infiltrates, and necrotic fibers. The involved antigen were shown in skeletal muscles by the immunoperoxidase technique as diffusely arranged granular intracytoplasmatic deposit for both IgC and total immunoglobulins. The coincidence between this technique and histologic muscle lesions was 11/18 (61(%) in 6 mo. and 6/8 (75%) at 9 mo. post-infection. In heart, delicate granular deposits of total immunoglobulins were seen diffusely arranged within the ventricular myocytes; coincidence between immunoperoxidase technique anl histologic involvement increased from 36 to 66% in animals sacrifeced 6 and 9 mo. post-infection. This strongly stressed the increase of immunologic phenomena with the chronification of infection. Concerning sensitivity, immunoperoxidase and direct immunofluorescence were highly sensitive in skeletal muscle (100%, p < 0.01). Conversely, direct immunofluorescence technique showed poor results in heart while immunoperoxidase increased its sensitivity from 21.4% (at 6 mo.) to 66.6% (at 9 mo.) post-infection (p < 0.001). Considering the necessity of obtaining an adequate vaccine in order to prevent this disease an experimental model like this, rendering immunological reactions as revealed by the immunoperoxidase technique, would be useful.

Vision based obstacle detection for all-terrain robots

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia Electrotécnica e de Computadores

Radiometric detection of metabolic activity of Paracoccidioides brasiliensis and its susceptibility to amphotericin B and diethylstilbestrol

Paracoccidioidomycosis (South American blastomycosis) is a systemic disease, strikingly more frequent in males, caused by the dimorphic fungus Paracoccidioides brasiliensis. A radiometric assay system has been applied to study the metabolic activity and the effect of drugs on this fungus "in vitro". The Y form of the yeast, grown in liquid Sabouraud medium was inoculated into sterile reaction vials containing the 6B aerobic medium along with 2.0 μCi of 14C-substrates. Control vials, prepared in the same way, contained autoclaved fungi. To study the effects of amphotericin B (AB) (0.1 and 10 μg/ml) and diethylstilbestrol (DSB) (1.0, 5.0 and 10 μg/ml) extra controls with live fungi and no drug were used. All vials were incubated at 35°C and metabolism measured daily with a Bactec instrument. 14CO2 production by P. brasiliensis was slow and could be followed for as long as 50 days. AB at 10mg/ml and DSB at 5 μg/ml inhibited the metabolism and had a cidal effect on this fungus. The results with DSB might explain the low incidence of the disease in females. This technique shows promise for studying metabolic pathways, investi gating more convenient 14C-substrates to expedite radiometric detection and for monitoring the effects of other drugs and factors on the metabolism of P. brasiliensis "in vitro".