Síndrome de Guillain-Barré: epidemiologia, prognóstico e fatores de risco

Introduction. Guillain-Barré syndrome (GBS) is an immune-mediated polyneuropathy and the principal cause of acute neuromuscular paralysis. The most prominent GBS subtypes are: acute inflammatory demyelinating polyneuropathy (AIDP), acute motor axonal neuropathy (AMAN), acute motor-sensory axonal neuropathy (AMSAN) and Fisher syndrome (FS). Differences in geographical distribution of variants have been reported. In Brazil, there are few studies describing the characteristics of GBS, but none on the frequency of GBS variants and their clinical manifestations. Infection-induced aberrant immune response resulting from molecular mimicry and formation of cross-reacting antibodies, contribute to complement activation. Functional biallelic polymorphism in immunoglobulin receptors that influence the affinity of IgG subclasses and the type of immune response have been described, suggesting genetic susceptibility to developing disease. It remains unclear whether individuals carrying different FCGR alleles have differential risk for GBS and⁄or disease severity. The goals of this study were: (1) To characterize GBS and describe the clinical findings in a cohort of patients with GBS from the state of Rio Grande do Norte, Brazil; (2) to determine whether polymorphism in FCGR were associated with development of GBS, and (3) to tease out whether the global gene expression studies could be a tool to identify pathways and transcriptional networks which could be regulated and decrease the time of disease. Methods. Clinical and laboratory data for 149 cases of GBS diagnosed from 1994 to 2013 were analyzed. Genomic DNA and total RNA were extracted from whole blood. Antigangliosides antibodies were determined in the sera. In addition, we also assessed whether FCGR polymorphism are present in GBS (n=141) and blood donors (n=364), and global gene expressions were determined for 12 participants with GBS. Blood samples were collected at the diagnosis and post-recovery. Results. AIDP was the most frequent variant (81.8%) of GBS, followed by AMAN (14.7%) and AMSAN (3.3%). The incidence of GBS was 0.3 ⁄ 100,000 people for the state of Rio Grande do Norte and cases occurred at a younger age. GBS was preceded by infections, with the axonal variant associated with episodes of diarrhea (P = 0.025). Proximal weakness was more frequent in AIDP, and distal weakness predominant in the axonal variant. Compared to 42.4% of cases with AIDP (P<0.0001), 84.6% of cases with the axonal variant had nadir in <10 days. Individuals with the axonal variant took longer to recover deambulation (P<0.0001). The mortality of GBS was 5.3%. A worse outcome was related to an axonal variant (OR17.063; P=0.03) and time required to improve one point in the Hughes functional scale (OR 1.028; P=0.03). The FCGR genotypes and allele frequencies did not differ significantly between the patients with GBS and the controls (FCGR2A p=0.367 and FCGR3A p=0.2430). Global gene expression using RNAseq showed variation in transcript coding for protein isoforms during acute phase of disease. Conclusions. The annual incidence of GBS was 0.3 per 100,00 and there was no seasonal pattern. A predominance of the AIDP variant was seen, and the incidence of the disease decreased with age. The distribution of weakness is a function of the clinical variants, and individuals with the axonal variant had a poorer prognosis. Early diagnosis and variant identification leads to proper intervention decreasing in long-term morbidity. FCGR polymorphisms do not seem to influence susceptibility to GBS in this population. This study found deregulated genes and signs of transcriptional network alterations during the acute and recovery phases in GBS. Identification of pathways altered during disease might be target for immune regulation and with potential to ameliorate symptoms.

Distribuição da fauna triatomínica e infecção natural pelo Trypanosoma cruzi em diferentes municípios do semiárido do Rio Grande do Norte

The triatomine fauna distribution and the natural infection by Trypanosoma cruzi was evaluated aiming the comprehension of the transmission dynamics of this parasite in the countryside of the State of Rio Grande do Norte. Additionally, the research for Trypanosoma rangeli was also investigated. The captures of triatomines were performed at sylvatic, peridomicile and domicile environments at different municipalities of the central and western mesoregions of this state. The insects were identified and examined by direct method, xenoculture and PCR to detect T. cruzi. The detection of T. rangeli was performed by direct examination of the hemolymph and multiplex PCR of 151 positive specimens for T. cruzi. Of 824 captured insects, the species were distributed in Triatoma brasiliensis (66.4%), Triatoma pseudomaculata (18.2%), Panstrongylus lutzi (12.7%) and Rhodnius nasutus (2.7%), and T. brasiliensis was found in most of the evaluated municipalities. The species were captured at nymph and adult stages, except P. lutzi, exclusively in adult stage. In the sylvatic environment were captured T. brasiliensis (57%), P. lutzi (28%) and T. pseudomaculata (15%) species. At the peridomicile environment were identified T. brasiliensis (74%), T. pseudomaculata (21%) and R. nasutus (5.0%), while in the intradomicile was found only T. brasiliensis. The infection rate of triatomines by T. cruzi was 30.4%, P. lutzi showed highest rate (78%), followed by T. brasiliensis (24.4%), T. pseudomaculata (22.6%) and R. nasutus (4.5%). Infected triatomines indexes at silvatic, peridomicile and domicile environments were of 41.8%, 20.1% and 50.0%, respectively. T. rangeli was only detected by multiplex PCR in 2.6% (4/151) of examined insects, of these 4.4% (3/67) were T. brasiliensis and 1.5% (1/63) P. lutzi species. The data showed that the positivity of P. lutzi allied to its ability to invade domicile attracted by light, suggests a likely participation of this insect between epidemiological transmission cycles of T. cruzi. T. brasiliensis was the only specie present in all environments, what reinforces its importance related to the capacity for adapting to the domestic environment, potential as a vector, and maintenance of sylvatic and domestic transmissions cycles in the semiarid, indicating the necessity of continuous epidemiological surveillance. The presence of T. rangeli in T. brasiliensis and P. lutzi was first recorded in rural zone of this State, broadening the area of occurrence of this protozoan in northeastern Brazil.

Distribuição da fauna triatomínica e infecção natural pelo Trypanosoma cruzi em diferentes municípios do semiárido do Rio Grande do Norte

The triatomine fauna distribution and the natural infection by Trypanosoma cruzi was evaluated aiming the comprehension of the transmission dynamics of this parasite in the countryside of the State of Rio Grande do Norte. Additionally, the research for Trypanosoma rangeli was also investigated. The captures of triatomines were performed at sylvatic, peridomicile and domicile environments at different municipalities of the central and western mesoregions of this state. The insects were identified and examined by direct method, xenoculture and PCR to detect T. cruzi. The detection of T. rangeli was performed by direct examination of the hemolymph and multiplex PCR of 151 positive specimens for T. cruzi. Of 824 captured insects, the species were distributed in Triatoma brasiliensis (66.4%), Triatoma pseudomaculata (18.2%), Panstrongylus lutzi (12.7%) and Rhodnius nasutus (2.7%), and T. brasiliensis was found in most of the evaluated municipalities. The species were captured at nymph and adult stages, except P. lutzi, exclusively in adult stage. In the sylvatic environment were captured T. brasiliensis (57%), P. lutzi (28%) and T. pseudomaculata (15%) species. At the peridomicile environment were identified T. brasiliensis (74%), T. pseudomaculata (21%) and R. nasutus (5.0%), while in the intradomicile was found only T. brasiliensis. The infection rate of triatomines by T. cruzi was 30.4%, P. lutzi showed highest rate (78%), followed by T. brasiliensis (24.4%), T. pseudomaculata (22.6%) and R. nasutus (4.5%). Infected triatomines indexes at silvatic, peridomicile and domicile environments were of 41.8%, 20.1% and 50.0%, respectively. T. rangeli was only detected by multiplex PCR in 2.6% (4/151) of examined insects, of these 4.4% (3/67) were T. brasiliensis and 1.5% (1/63) P. lutzi species. The data showed that the positivity of P. lutzi allied to its ability to invade domicile attracted by light, suggests a likely participation of this insect between epidemiological transmission cycles of T. cruzi. T. brasiliensis was the only specie present in all environments, what reinforces its importance related to the capacity for adapting to the domestic environment, potential as a vector, and maintenance of sylvatic and domestic transmissions cycles in the semiarid, indicating the necessity of continuous epidemiological surveillance. The presence of T. rangeli in T. brasiliensis and P. lutzi was first recorded in rural zone of this State, broadening the area of occurrence of this protozoan in northeastern Brazil.

Análise do perfil imunológico e citohistológico durante a transmissão vertical de Trypanosoma cruzi em diferentes estágios da infecção experimental

Trypanosma cruzi is the causative agent of Chagas disease. This trypanosomiasis has become a global public health problem due to migration of Latin Americans to non-endemic countries. In Latin America with the succesful implementation of control domiciliated vector infestation and blood transfusion, the importance of congenital transmission has recently increased. Considering the tight regulation of immune system during gestation, we aimed to investigate the changes in the immune system caused by T.cruzi infection in the gestation outcome. T cruzi G and Y strain were used to infect female BALB/c mice before or after mating with non-infected male mice. The presence of vaginal plug was used as indicative of mating. Females were euthanized 8 days after confirmation of vaginal plug. We used three female control groups, only infected, only infected and non-infected and non-pregnant females. Two groups were infected before mating and other two were infected 4 days after confirmation of vaginal plug. The uterus and spleen were collected to immunochemistry, qPCR, immunofluorescence and cytokine analysis. Our results showed that despite the MMP’s identification being similarly among groups, T.cruzi higher virulent strain can impaire gestation outcome prior mating; the infection also increased cytokines like IFN-γ, IL-1β and IL-4; and leucocytes in uterine environment was altered, responding locally to systemic changes caused by T.cruzi infection. In conclusion this work suggests that T.cruzi infection can impaire gestation outcome and local response to sistemic infection was able to control the infection allowing pregnancy development in some conditions.

Estrategias para la mejora del diagnóstico serológico de la besnoitiosis bovina

Besnoitia besnoiti es un protozoo apicomplejo formador de quistes responsable de la besnoitiosis bovina, una enfermedad crónica y debilitante que origina importantes pérdidas económicas en el ganado bovino a nivel mundial. En la actualidad, no existen tratamientos ni vacunas disponibles y, por tanto, las medidas de control se deben basar en la detección de animales infectados para reducir la prevalencia en zonas endémicas y evitar la entrada de la enfermedad en zonas libres a través de la compra de animales infectados. Los principales retos en la investigación sobre este parásito son, por un lado, la mejora de las técnicas serológicas para realizar un diagnóstico preciso y, por otro lado, el empleo de las nuevas pruebas diagnósticas desarrolladas para determinar el impacto de la enfermedad mediante estudios de prevalencia e incidencia. Dada la rápida diseminación de la besnoitiosis bovina en Europa, se han desarrollado numerosas técnicas de diagnóstico serológico. Sin embargo, éstas no han sido validadas en estudios comparativos y, por ello, los datos epidemiológicos descritos por los diferentes laboratorios, no son comparables. Además, no se ha establecido una prueba de referencia, lo cual es de vital importancia para el establecimiento de un protocolo de diagnóstico común entre los países afectados. Por otra parte, se ha puesto de manifiesto la necesidad de mejorar la sensibilidad (Se) de las pruebas para detectar a los animales infectados durante la fase aguda, así como los infectados durante la fase crónica que presentan niveles bajos de anticuerpos, los cuales en diversas ocasiones se encuentran por debajo del punto de corte de las técnicas diagnósticas. Además, también es necesario mejorar su especificidad (Esp), ya que las actuales pruebas ELISA, que se emplean de forma rutinaria en el diagnóstico de la infección, pueden dar lugar a un elevado número de resultados falsos-positivos que pueden repercutir de forma negativa en la eficacia de los planes de control...

O uso da PCR em tempo real para o estudo da carga parasitária e dos níveis transcricionais durante a infecção experimental por Trypanosoma cruzi

Trypanosoma cruzi is causative agent of Chagas disease, one of most neglected tropical diseases. Estimated that about 11 million people worldwide are infected by T. cruzi and about 6 to 7 million people are at risk in endemic areas. During the process of invasion of host and parasite interact enabling signal transduction and gene expression modulation in response to invasion. The diversity of activated proteins and pathways to repair the damage by disruption of the plasma membrane interest to us and thus present study developed a new form of detection and quantitation by polymerase chain reaction in real time (qPCR) of parasitic load T. cruzi and quantified transcriptional levels relative (RT-qPCR) of dysferlin, Sphingomyelin acid esferase (ASM), transcription factor EB (TFEB) Galectins 1 and 3 and Annexin A2. This study demonstrated that quantification by real time PCR using primers P21fw and P21rv was specific and sensitive for detection of T. cruzi in vivo and in vitro, as well as transcriptional levels of genes related to cytoskeletal organization and repair plasma membrane are modulated in response to damage generated by parasite.

From genes to radioresistance in head and neck squamous cell carcinoma

Head and Neck Cancers (HNC) are a group of tumours located in the upper aero-digestive tract. Head and Neck Squamous Cell Carcinoma (HNSCC) represent about 90% of all HNC cases. It has been considered the sixth most malignant tumour worldwide and, despite clinical and technological advances, the five-year survival rate has not improved much in the last years. Nowadays, HNSCC is well established as a heterogeneous disease and that its development is due to accumulation of genetic events. Apart from the majority of the patients being diagnosed in an advanced stage, HNSCC is also a disease with poor therapeutic outcome. One of the therapeutic approaches is radiotherapy. However, this approach has different drawbacks like the radioresistance acquired by some tumour cells, leading to a worse prognosis. A major knowledge in radiation biology is imperative to improve this type of treatment and avoid late toxicities, maintaining patient quality of life in the subsequent years after treatment. Then, identification of genetic markers associated to radiotherapy response in patients and possible alterations in cells after radiotherapy are essential steps towards an improved diagnosis, higher survival rate and a better life quality. Not much is known about the radiation effects on cells, so, the principal aim of this study was to contribute to a more extensive knowledge about radiation treatment in HNSCC. For this, two commercial cell lines, HSC-3 and BICR-10, were used and characterized resorting to karyotyping, aCGH and MS-MLPA. These cell lines were submitted to different doses of irradiation and the resulting genetic and methylation alterations were evaluated. Our results showed a great difference in radiation response between the two cell lines, allowing the conclusion that HSC-3 was much more radiosensitive than BICR-10. Bearing this in mind, analysis of cell death, cell cycle and DNA damages was performed to try to elucidate the motifs behind this difference. The characterization of both cell lines allowed the confirmation that HSC-3 was derived from a metastatic tumour and the hypothesis that BICR-10 was derived from a dysplasia. Furthermore, this pilot study enabled the suggestion of some genetic and epigenetic alterations that cells suffer after radiation treatment. Additionally, it also allowed the association of some genetic characteristics that could be related to the differences in radiation response observable in this two cell lines. Taken together all of our results contribute to a better understanding of radiation effects on HNSCC allowing one further step towards the prediction of patients’ outcome, better choice of treatment approaches and ultimately a better quality of life.

Anticorpos anti-trypanosoma cruzi como preditivos de infecção por leishmania infantum

Leishmania infantum and Trypanosoma cruzi are trypanosomatids of medical importance and are, respectively, the etiologic agents of visceral leishmaniasis (VL) and Chagas disease (CD) in Brazil. People infected with L. infantum or T. cruzi may develop asymptomatically, enabling the transmission of pathogens through blood transfusion and / or organs. The assessment of the infection by T. cruzi is included among the tests performed for screening blood donors in Brazil, however, there is no availability of tests for Leishmania. Serological tests for T. cruzi are very sensitive, but not specific, and may have cross-reactions with other microorganisms. Thus, the aim of this study was to determine the prevalence of Leishmania infection in blood donors and assess whether the serological test for T. cruzi detect L. infantum. Among the 300 blood samples from donors, discarded in 2011, 61 were T. cruzi positive, 203 were from donors with other infections and 36 were from handbags with low blood volume, but without infection. We also assessed 144 samples from donors without infections and able to donate blood, totaling 444 subjects. DNA was extracted from blood samples of all to perform quantitative PCR (qPCR) to detect Leishmania DNA. The buffy coat obtained from all samples was grown in Schneider medium supplemented and NNN. All samples were evaluated for the presence of anti-Leishmania antibody. The serological results indicate a percentage of 22% of Leishmania infection in blood samples obtained from discarded bags. A total of 60% of samples positive in ELISA for T. cruzi were negative by IFI, used as confirmatory test, ie 60% false positive for Chagas. Among these samples false positive for Chagas, 72% were positive by ELISA for Leishmania characterizing the occurrence of cross reaction between serologic assays. Of the 300 cultures performed, 18 grew parasites that were typed by qPCR and specific isoenzymes, found the species Leishmania infantum crops. Among the 18 cultures, 4 were purged from scholarships for low volume and all negative serology blood bank, thus demonstrating that there is a real risk of Leishmania transmission via transfusion. It is concluded that in an area endemic for leishmaniasis in Brazil, serological diagnosis performed to detect infection by T. cruzi among blood donors can identify infection by L. infantum and although cause false positive for Chagas, this cross-reactivity reduces the risk of Leishmania infection via blood transfusion, since tests are not applied specific detection of the parasite. In this way, there remains the need to discuss the implementation of a specific serological screening test for Leishmania in endemic countries such as Brazil

Clínica e cirurgia de animais de companhia

Este relatório foi realizado no âmbito da conclusão do mestrado integrado em medicina veterinária da Universidade de Évora, encontrando-se dividido em duas partes. A primeira é referente à casuística acompanhada ao longo do estágio curricular, decorrido no Hospital Veterinário do Restelo (HVR), com a duração de quatro meses, desde 03 de Agosto de 2015 a 06 de Dezembro de 2016, sob orientação da Doutora Sandra Branco e coorientação do Dr. Diogo Magno, subdiretor clínico do HVR. A segunda parte é constituída por uma monografia subordinada ao tema “Erliquiose Monocítica Canina”, seguida de um caso clínico acompanhado pelo autor no âmbito do referido tema. A erliquiose monocítica canina (EMC) é uma doença infeciosa transmitida por um vetor, o ixodídeo Riphicephalus sanguineus, cujos controlos químicos e ambientais são essenciais para reduzir a prevalência da doença. É causada por uma bactéria intracelular, Ehrlichia canis, que afeta o sistema imunitário dos cães, manifestando diferentes fases de evolução e podendo apresentar formas aguda e crónica da doença. O tratamento de primeira escolha é o uso da antibioterapia com tetraciclinas, dentre as quais a doxiciclina, para além do tratamento de suporte, como a fluidoterapia. O prognóstico é variável, dependendo da precocidade e eficiência da terapêutica instituída; ABSTRACT: The present report, wrote to get the master degree in veterinary medicine area, on Universidade de Évora, is divided up into two distinct parts. On one hand it describes the clinical situations’ roll, assisted through the experimental trainee, that took place on Hospital Veterinário do Restelo (HVR), for a period of four months, specifically since 3 august 2015 until 6 december 2015, and this trainee was led by Doctor Sandra Branco, and also the HVR’s clinical subdirector Dr. Diogo Magno. On other hand the second parts reveals a monograph titled “ehrlichiosis monocytic canine” (EMC), specifying a particular clinical case followed by the author. The EMC an infectious disease transmitted by a tick - Riphicephalus sanguineus – whose chemical controls and even the environmental ones are crucial to reduce the disease’s prevalence. The disease has an intracellular bacteria origin - Ehrlichia canis – responsability for the dog’s immune system infection, and it reveals different evolution phases and present acute or in some cases chronic forms. The treatment’s first step is to use an antibiotic with tetracycline that include doxycycline, and as a fluid’s therapy addition is use to do the supportive treatment. The diagnosis is variable so it depends on precocity evaluation and even on the therapeutics efficiencies.

Detecção parasitológica e molecular de tripanossomatídeos em triatomíneos sinantrópicos e primatas neotropicais no Brasil central

Tese (doutorado)—Universidade de Brasília, Faculdade de Medicina, Programa de Pós-Graduação em Medicina Tropical, 2016.

Contribution to the study of prognostic factors in canine oral squamous cell carcinoma

Tese de Doutoramento em Ciências Veterinárias, na Especialidade de Clínica

Clínica de animais de companhia

O presente relatório pretende descrever as atividades desenvolvidas durante o estágio curricular, realizado no Hospital Veterinário do Restelo, no período de 4 de agosto a 31 de janeiro. A hipertensão sistémica é uma doença insidiosa e progressiva, que se não controlada pode provocar lesões irreversíveis em órgãos alvo. Nos animais o seu desenvolvimento é normalmente secundário a processos de doença ou à administração exógena de alguns fármacos. Nos cães as causas mais comuns compreendem a doença renal crónica, a doença renal aguda e o hiperadrenocorticismo, enquanto nos gatos o seu desenvolvimento está, normalmente, associado à doença renal crónica, ao hipertiroidismo e ao hiperaldosteronismo primário. O diagnóstico da hipertensão e da causa primária responsável pelo seu desenvolvimento constituem um desafio clínico, criado por um conjunto diversificado de fatores associados aos animais, aos métodos de medição indiretos, processos de doença concorrentes e financeiros; Abstract: Small animal clinics The present report aims to describe the activities developed during the traineeship realized at Hospital Veterinário do Restelo, from August 4 to January 31. Systemic hypertension is an insidious and progressive disease, which uncontrolled is responsible for irreversible damage in target organs. In animals, their development is usually secondary to disease processes or exogenous administration of some drugs. In dogs, the most common causes include chronic kidney disease, acute renal disease and hyperadrenocorticism, while in cats their development is usually associated with chronic kidney disease, hyperthyroidism and primary aldosteronism. The diagnosis of hypertension and the primary cause responsible for its development are a clinical challenge created by a diverse set of factors associated with the animals, the indirect measurement methods, concurrent disease processes and financial.

Aceitação sensorial da bebida açaí batido após tratamento térmico dos frutos.

O açaí (Euterpe oleracea Mart.) é uma fruta nativa da floresta amazônica tendo seu consumo mundial impulsionado devido à presença de antocianinas e sua capacidade antioxidante (1,2). O mercado consumidor interno regional amazônico, bastante tradicional e peculiar, tem preferência pelo produto processado sem qualquer tratamento térmico e para consumo imediato (3). No Brasil, este tipo de bebida tem sido relacionado a casos crescentes de doença de Chagas (4), devido à contaminação dos frutos pelo protozoário Trypanosoma cruzi (5), agente causal da doença, podendo ser inativado pelo tratamento térmico por branqueamento dos frutos a 80 °C por 10s. Entretanto, o fruto de açaí também apresenta elevada carga microbiana patogênica que quando não tratada adequadamente é repassada para o produto final (6). Outra importante fonte de contaminação microbiológica da bebida é a água utilizada durante todas as operações de processamento, pois mais de 50% dos municípios localizados na região amazônica brasileira não realizam a cloração simples da água (7). Um aspecto importante a ser considerado é que o tipo de processamento, mesmo melhorando a qualidade microbiológica, não pode interferir no perfil qualitativo sensorial do produto e influenciar na aceitabilidade pelo consumidor tradicional de açaí batido. Neste sentido, este trabalho propôs estudar o impacto sensorial de alternativas térmicas eficazes como tratamentos de sanitização de frutos de açaí, que fossem factíveis de implementação para o processador artesanal, e que seu produto fosse aceitável para o consumidor tradicional.

Epidemiologia e controle das doenças transmissíveis no Brasil

Na década de 1930, as doenças transmissíveis foram a principal causa de morte nas capitais do Brasil. As melhorias sanitárias, o desenvolvimento de novas tecnologias, como as vacinas e os antibióticos, a ampliação do acesso aos serviços de saúde e as medidas de controle fizeram com que esse quadro se modificasse bastante até os dias de hoje. Porém, mesmo diante dos notórios avanços obtidos para controlar essas doenças, elas ainda se constituem como importante problema de saúde pública no país. Fatores de ordem biológica, geográfica, ecológica, social, cultural e econômica atuam simultaneamente na produção, distribuição e controle das doenças. O controle de doenças vetoriais, tais como: doença de Chagas, malária, leishmanioses, esquistossomose, febre amarela e dengue, depende de ações conjuntas de todos os níveis de atenção à saúde. Diante disso, este material foca em como a equipe de atenção básica pode atuar no controle e combate dessas doenças.

Cuidados em doenças infecciosas e parasitárias: endêmicas, emergentes e re-emergentes

Este módulo é dividido em nove lições e aborda epidemiologia, manifestações clínicas, diagnóstico, tratamento, medidas de controle e vigilância epidemiológica das seguintes doenças: Influenza, Febre Amarela, Leishmaniose, Malária, Doença de Chagas, Parasitoses, Esquistossomose, Doenças Sexualmente Transmissíveis e Hantavirose.