Histopathology, serology and cultures in the diagnosis of cryptococcosis

Cryptococcosis is one of the most common opportunistic fungal infections in patients with acquired immunodeficiency syndrome (AIDS). We report 13 cases of cryptococcal infection based on histopathology, serology and cultures. Epidemiological analysis, histochemical techniques of hematoxilin and eosin (HE) and Grocot's silver (GMS), as well special histochemical techniques such as Mayer's mucicarmine (MM) and Fontana-Masson (FM), cryptococcal antigen test (CrAg) and isolation on fungal media: Sabouraud's (SAB), brain-heart infusion agar (BHI) and canavanine-glycine-bromothymol blue (CGB) agar were analyzed. Unsatisfactory staining results by MM stain associated to negative titers by CrAg test, which FM stain confirmed that capsule-deficient Cryptococcus infections were observed in four cases. Eight isolated cases were identified as follows: six cases were infection with Cryptococcus neoformans and two cases were Cryptococcus gattii.

Seroprevalence of hepatitis B and C infection markers among children and adolescents in the southern Brazilian region

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections account for a substantial proportion of liver diseases worldwide. The aim of this study was to determine the prevalence of HBV and HCV serological markers among children and adolescents and verify the epidemiology of the HBV infection over than a decade of the introduction of vaccination program. Serologic markers to HBsAg, total anti-HBc and anti-HCV had been tested in 393 samples. The seropositivity for HBsAg was 0.76% and for total anti-HBc was 1.02%. Copositivity between HBsAg and total anti-HBc was verified in 0.76% of the analyzed samples. There was no seropositivity for anti-HCV marker. The seroprevalence of HBV infection markers among children and adolescents in the southern Brazilian region is high compared to that reported in other countries. Preventive measures, such as educational activities in addition to the universal childhood HBV vaccination, should be initiated in order to reduce the morbimortality and the economic burden associated with the disease.

Use of elisa employing homologous and heterologous antigens for the detection of IgG and subclasses (IgG1 and IgG2) in the diagnosis of Canine visceral leishmaniasis

Indirect immunofluorescence is the method recommended for the diagnosis of visceral leishmanisis in dogs, however, the accuracy of this technique is low and its use on a large scale is limited. Since ELISA does not present these limitations, this technique might be an option for the detection of IgG or specific IgG1 and IgG2 subclasses. Canine ehrlichiosis is an important differential diagnosis of American Visceral Leishmaniasis (AVL). The present study compared ELISA using Leishmania chagasi and Leishmania braziliensis antigen for the detection of anti-Leishmania IgG and subclasses in serum samples from 37 dogs naturally infected with L. chagasi (AVL) and in samples from four dogs co-infected with L. braziliensis and L. chagasi (CI). The occurrence of cross-reactivity was investigated in control serum samples of 17 healthy dogs (HC) and 35 infected with Ehrlichia canis (EC). The mean optical density obtained for the detection of IgG was significantly higher when L. chagasi antigen was used, and was also higher in subgroup VLs (symptomatic) compared to subgroup Vla (asymptomatic). The correlation between IgG and IgG1 was low. The present results suggest that IgG ELISA using homologous antigen yields the best results, permitting the diagnosis of asymptomatic L. chagasi infection and the discrimination between cases of AVL and ehrlichiosis in dogs.

High prevalence of the simultaneous excretion of polyomaviruses JC and BK in the urine of HIV-infected patients without neurological symptoms in São Paulo, Brazil

OBJECTIVE: To evaluate the prevalence of the urinary excretion of BKV and JCV in HIV-infected patients without neurological symptoms. METHODS: Urine samples from HIV-infected patients without neurological symptoms were tested for JC virus and BK virus by PCR. Samples were screened for the presence of polyomavirus with sets of primers complementary to the early region of JCV and BKV genome (AgT). The presence of JC virus or BK virus were confirmed by two other PCR assays using sets of primers complementary to the VP1 gene of each virus. Analysis of the data was performed by the Kruskal-Wallis test for numerical data and Pearson or Yates for categorical variables. RESULTS: A total of 75 patients were included in the study. The overall prevalence of polyomavirus DNA urinary shedding was 67/75 (89.3%). Only BKV DNA was detected in 14/75 (18.7%) urine samples, and only JCV DNA was detected in 11/75 (14.7%) samples. Both BKV and JCV DNA were present in 42/75 (56.0%) samples. CONCLUSION: In this study we found high rates of excretion of JCV, BKV, and simultaneous excretion in HIV+ patients. Also these results differ from the others available on the literature.

USE OF MUELLER-HINTON BROTH AND AGAR IN THE GERM TUBE TEST

Candida albicans is often isolated from clinical samples, thus its presumptive differentiation from other species of the same genus can be based on its ability to form the germ tube in human serum. Nevertheless, there are two other species that share this characteristic: C. dubliniensis and C. africana. The aim of this study was to compare four different substrates to perform the germ tube (GT) test. The Candida spp. isolates were identified using a manual system (135 C. albicans, 24 C. tropicalis and one C. dubliniensis). The germ tube test was performed with fresh, previously frozen serum and Mueller-Hinton (MH) broth and agar. GT was observed in 96% (130/136) of the isolates through the fresh serum technique, 94% (128/136) through previously frozen serum, 92% (125/136) in MH agar, and 90% (122/136) in MH broth. The sensitivity of each test was higher than 90%, with 100% specificity. Both the MH agar and broth were able to identify the true positives, and false positives were not found. However, some C. albicans isolates were not identified. MH agar and broth may be used in laboratory for the rapid presumptive identification of C. albicans, as an alternative method for germ tube test.

Embracing transience and subjectivity in the conservation of complex contemporary artworks: contributions from ethnographic and psychological paradigms

Dissertação para obtenção do Grau de Mestre em Conservação e Restauro, Perfil Ciências da Conservação Especialização em Arte Contemporânea

Understanding the relationship between central metabolism and virulence in the human pathogen Streptococcus pneumoniae

Dissertation presented to obtain the Ph.D. degree in Biochemistry

Precious transition metals: the importance of Zn2+, Mn2+ and Cu2+ in the human pathogen Enterococcus faecalis

Dissertation presented to obtain the Ph.D degree in Biology

CHAGASIC MENINGOENCEPHALITIS IN AN HIV INFECTED PATIENT WITH MODERATE IMMUNOSUPPRESSION: PROLONGED SURVIVAL AND CHALLENGES IN THE HAART ERA

The reactivation of Chagas disease in HIV infected patients presents high mortality and morbidity. We present the case of a female patient with confirmed Chagasic meningoencephalitis as AIDS-defining illness. Interestingly, her TCD4+ lymphocyte cell count was 318 cells/mm3. After two months of induction therapy, one year of maintenance with benznidazol, and early introduction of highly active antiretroviral therapy (HAART), the patient had good clinical, parasitological and radiological evolution. We used a qualitative polymerase chain reaction for the monitoring of T. cruzi parasitemia during and after the treatment. We emphasize the potential value of molecular techniques along with clinical and radiological parameters in the follow-up of patients with Chagas disease and HIV infection. Early introduction of HAART, prolonged induction and maintenance of antiparasitic therapy, and its discontinuation are feasible, in the current management of reactivation of Chagas disease.

Mergers and acquisitions in the banking sector: An empirical review of the impact of merger announcement on abnormal returns

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

The integration of online advertising: The effects of source expertise and certainty level of the message on consumer involvement and persuasion in the context of user-generated advertising

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

The compliance function in banking: Perspective and future in the age of globalization

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

ISO 9001:2000 - advantages and obstacles in the portuguese construction business

Innovations in Structural Engineering and Construction - ISEC, 2008