Descrição de duas novas espécies do género Nevskia da classe Gammaproteobacteria

Dissertação para obtenção do Grau de Mestre em Genética Molecular e Biomedicina

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.

In vitro and in vivo antileishmanial efficacy of a combination therapy of diminazene and artesunate against Leishmania donovani in BALB/c mice

The in vitro and in vivo activity of diminazene (Dim), artesunate (Art) and combination of Dim and Art (Dim-Art) against Leishmania donovani was compared to reference drug; amphotericin B. IC50 of Dim-Art was found to be 2.28 ± 0.24 µg/mL while those of Dim and Art were 9.16 ± 0.3 µg/mL and 4.64 ± 0.48 µg/mL respectively. The IC50 for Amphot B was 0.16 ± 0.32 µg/mL against stationary-phase promastigotes. In vivo evaluation in the L. donovani BALB/c mice model indicated that treatments with the combined drug therapy at doses of 12.5 mg/kg for 28 consecutive days significantly (p < 0.001) reduced parasite burden in the spleen as compared to the single drug treatments given at the same dosages. Although parasite burden was slightly lower (p < 0.05) in the Amphot B group than in the Dim-Art treatment group, the present study demonstrates the positive advantage and the potential use of the combined therapy of Dim-Art over the constituent drugs, Dim or Art when used alone. Further evaluation is recommended to determine the most efficacious combination ratio of the two compounds.

Evaluation of GBV-C / HVG viremia in HIV-infected women

The present study aimed at standardizing a real-time quantitative polymerase chain reaction assay to evaluate the presence of GBV-C/HGV RNA. A "TaqMan" assay using primers and probe derived from the 5¢ NCR region was developed and validated. Two hundred and fifty-three plasma samples from HIV-infected women were tested for GBV-C viremia and antibody against the envelope protein 2. GBV-C RNA was detected in 22.5% of the patients whereas the antibody was identified in 25.3% of the cohort. Detection of viral RNA and of antibodies was mutually exclusive. Viral loads showed a mean of 1,777 arbitrary units / mL, being 1.1 and 13,625 arbitrary units / mL respectively the lowest and highest values measured. We conclude that the real-time quantitative polymerase chain reaction method developed is appropriate for the investigation of GBV-C RNA since it was shown to be highly specific and sensitive, as well as requiring few steps, preventing contamination and providing additional information as to the relative viremia of carriers, a parameter that must be included in studies evaluating the co-factors influencing the clinical outcome of HIV/AIDS.

Hepatitis C virus infection in hemodialysis patients in Maracaibo, Venezuela

Over a two year period, the incidence of hepatitis C virus (HCV) infection was evaluated in 29 hemodialysis patients, aged between 15 and 75 years (mean ± SD: 45 ± 39.5 years), from the University Hospital Hemodyalisis Unit, Maracaibo, Zulia State, Venezuela. Anti-HCV antibodies were determined using a fourth generation ELISA (Innotest HCV Ab IV) kit and positive blood samples were tested using a recombinant assay kit (Inno-LIA HCV Ab III), both kits from Innogenetics N.V., Belgium. The findings indicate a lack of HCV seroconversion in the hemodialysis patients over the study period, confirmed by the recombinant assay. Risk factors for HCV infection were 0.3270 (95% confidence interval: 0.01323-8.080) in patients undergoing hemodialysis. The findings suggest a lack of significant sources for HCV infection due to the preventive measures to avoid its transmission in the hemodialysis unit.

A guerra numa sociedade democrática em crise: Atenas no final do Séc. V a.C.

Falar sobre a Guerra do Peloponeso é falar sobre a guerra que dividiu a Grécia, opondo Esparta e Atenas, com conseqüências gravíssimas para esta última cidade. Simultaneamente, foi o fim da mais conhecida experiência democrática da antiga Grécia. No entanto, o nosso objectivo não é falar sobre essa experiência, ou sobre as conseqüências da Guerra do Peloponeso, mas sobre o modo como ela foi encarada pelos Atenienses. Importa, em primeiro lugar, recordar a situação de Atenas no início da guerra, o que significa ter em conta dois aspectos: a estrutura política de Atenas e o seu domínio marítimo. Desde Sôlon e das suas reformas, que Atenas caminhava no sentido da consolidação de uma estrutura política que respeitasse os direitos dos seus cidadãos e o aumento da sua participação nos órgãos deliberativos da polis. Em 462 a.C, Efialtes (com o apoio de Péricles) reduziu os poderes do Areópago, privando-o de quaisquer funções legislativas e judiciais e deixando- -Ihe apenas o direito de superintender nos casos de homicídio e nos delitos de caracter religioso. Na verdade, Efialtes e Péricles consideravam que, sendo o Areópago constituído por membros vitalícios provenientes das classes mais elevadas, a concentração nele de tais poderes judiciários era contrária ao espírito democrático, afastando assim da constituição ateniense os últimos vestigios de privilégios da aristocracia.

Effects of vitamin C supplementation on acute phase Chagas disease in experimentally infected mice with Trypanosoma cruzi QM1 strain

The tissue changes that occur in Chagas disease are related to the degree of oxidative stress and antioxidant capacity of affected tissue. Studies with vitamin C supplementation did not develop oxidative damage caused by Chagas disease in the host, but other studies cite the use of peroxiredoxins ascorbate - dependent on T. cruzi to offer protection against immune reaction. Based on these propositions, thirty "Swiss" mice were infected with T. cruzi QM1 strain and treated with two different vitamin C doses in order to study the parasitemia evolution, histopathological changes and lipid peroxidation biomarkers during the acute phase of Chagas disease. The results showed that the parasite clearance was greater in animals fed with vitamin C overdose. There were no significant differences regarding the biomarkers of lipid peroxidation and inflammatory process or the increase of myocardium in animals treated with the recommended dosage. The largest amount of parasite growth towards the end of the acute phase suggests the benefit of high doses of vitamin C for trypomastigotes. The supplementation doesn't influence the production of free radicals or the number of amastigote nests in the acute phase of Chagas disease.

Caracterização química de contas de vidro arqueológicas do século VII a.C. provenientes da Quinta do Almaraz, Cacilhas

Dissertação para obtenção do Grau de Mestre em Ciências da Conservação, Departamento de Conservação e Restauro

C-reactive protein at 24 hours after hospital admission may have relevant prognostic accuracy in acute pancreatitis: a retrospective cohort study

Introduction: C-reactive protein (CRP) and Bedside Index for Severity in Acute Pancreatitis (BISAP) have been used in early risk assessment of patients with AP. Objectives: We evaluated prognostic accuracy of CRP at 24 hours after hospital admission (CRP24) for in-hospital mortality (IM) in AP individually and with BISAP. Materials and Methods: This retrospective cohort study included 134 patients with AP from a Portuguese hospital in 2009---2010. Prognostic accuracy assessment used area under receiver---operating characteristic curve (AUC), continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI). Results: Thirteen percent of patients had severe AP, 26% developed pancreatic necrosis, and 7% died during index hospital stay. AUCs for CRP24 and BISAP individually were 0.80 (95% confidence interval (CI) 0.65---0.95) and 0.77 (95% CI 0.59---0.95), respectively. No patients with CRP24 <60 mg/l died (P = 0.027; negative predictive value 100% (95% CI 92.3---100%)). AUC for BISAP plus CRP24 was 0.81 (95% CI 0.65---0.97). Change in NRI nonevents (42.4%; 95% CI, 24.9---59.9%) resulted in positive overall NRI (31.3%; 95% CI, − 36.4% to 98.9%), but IDI nonevents was negligible (0.004; 95% CI, − 0.007 to 0.014). Conclusions: CRP24 revealed good prognostic accuracy for IM in AP; its main role may be the selection of lowest risk patients.

THE INFLUENCE OF HIV-1 SUBTYPES C, CRF31_BC AND B ON DISEASE PROGRESSION AND INITIAL VIROLOGIC RESPONSE TO HAART IN A SOUTHERN BRAZILIAN COHORT

Background: Although most HIV-1 infections in Brazil are due to subtype B, Southern Brazil has a high prevalence of subtype C and recombinant forms, such as CRF31_BC. This study assessed the impact of viral diversity on clinical progression in a cohort of newly diagnosed HIV-positive patients. Methods: From July/2004 to December/2005, 135 HIV-infected patients were recruited. The partial pol region was subtyped by phylogeny. A generalized estimating equation (GEE) model was used to examine the relationship between viral subtype, CD4+ T cell count and viral load levels before antiretroviral therapy. Hazard ratio (Cox regression) was used to evaluate factors associated with viral suppression (viral load < 50 copies/mL at six months). Results: Main HIV-1 subtypes included B (29.4%), C (28.2%), and CRF31_BC (23.5%). Subtypes B and C showed a similar trend in CD4+ T cell decline. Comparison of non-B (C and CRF31_BC) and B subtypes revealed no significant difference in the proportion of patients with viral suppression at six months (week 24). Higher CD4+ T cell count and lower viral load were independently associated with viral suppression. Conclusion: No significant differences were found between subtypes; however, lower viral load and higher CD4+ T cell count before therapy were associated with better response.

Sulfite Oxidase Deficiency – An Unusual Late and Mild Presentation

Introduction: Sulfite oxidase deficiency (SOD) is an autosomal recessive inherited disease usually presenting in the neonatal period with severe neurological symptoms including seizures, often refractory to anticonvulsant therapy, and a rapidly progressive encephalopathy resembling neonatal hypoxic ischemia, with premature death. Most patients develop dislocated ocular lenses. Later or milder presentations of SOD are being reported with increasing frequency. These presentations include neurological regression with loss of previously acquired milestones or movement disorders. Case report: We report a four years old girl presenting with intermittent ataxia and uncoordinated limb movements. A similar episode of ataxia had occurred previously, one year before, with complete neurologic recovery and normal developmental milestones. Bilateral lens dislocation had been recently diagnosed. Cranial MRI demonstrated bilateral globus pallidus enhancement. Low homocysteine was found in plasma and SulfitestR was positive. Further investigations led to confirmation of isolated sulfite oxidase deficiency with no enzyme activity detected on skin fibroblasts culture. Discussion: This case illustrates the clinical variability of SOD and it is not only atypical but also seems to be the mildest form described so far. The association of ectopia lentis with a movement disorder, even without psychomotor regression, should prompt us to look for this diagnosis.

Detecção e Quantificação de Neurónios em C.elegans

Nesta dissertação é apresentado um estudo dos sistemas de processamento automático de imagem em contexto de um problema relacionado com a individualização de neurónios em imagens da nematoda C. elegans durante estudos relacionados com a doença de Parkinson. Apresenta-se uma breve introdução à anatomia do verme, uma introdução à doença de Parkinson e uso do C. elegans em estudos relacionados e também é feita a análise de artigos em contexto de processamento de imagem para contextualizar a situação atual de soluções para o problema de extração de características e regiões específicas. Neste projeto é desenvolvida uma pipeline com o auxilio do software CellProfiler para procurar uma resposta para o problema em questão.

Tratamento da Co-Infecção do Vírus da Hepatite B e C. Resposta Excedida

Os vírus da hepatite B (VHB) e da hepatite C (VHC) constituem a causa mais frequente de doença hepática crónica. A partilha de vias de transmissão contribui para o risco de coinfecção VHB-VHC. Nos doentes co-infectados com o VHB e VHC verifica-se uma progressão mais rápida para a cirrose hepática e existe um risco aumentado para o carcinoma hepatocelular. A terapêutica da co-infecção VHB/VHC é empírica, consistindo na indicada para a infecção exclusiva pelo VHC, o qual, na maioria dos casos, é o vírus dominante. A utilização do tratamento padrão para a hepatite C, nomeadamente interferão alfa peguilado e ribavirina, não mostra diferenças significativas na resposta virológica sustentada ao VHC comparativamente com a dos monoinfectados pelo VHC. É incerto o benefício da associação de análogos dos nucleós(t)idos. A acção terapêutica pode modificar a interacção entre os dois vírus e, designadamente, exacerbar a doença por reactivação do VHB. Os autores apresentam o caso clínico de uma doente com co-infecção VHB-VHC, sem reconhecimento de vírus dominante, em que a resposta à terapêutica instituída superou a expectativa da evidência científica disponível.

ELEVATED TRANS-MAMMARY TRANSMISSION OF Toxocara canis LARVAE IN BALB/c MICE

Toxocariasis is a widespread zoonosis and is considered an important worldwide public health problem. The aim of this study was to investigate the frequency of trans-mammary Toxocara canis infection in newborn BALB/c mice nursed by females experimentally infected with 1,200 eggs after delivery. After 50 days of age, the presence of larvae in different organs of the offspring was investigated. Trans-mammary infection was confirmed in 73.9% of the mice that had been nursed by infected females. These data show a high trans-mammary transmission of T. canis and confirm the significance of this transmission route in paratenic hosts.