Thesis--M.D., University of Hong Kong. / Typescript.

published_or_final_version / Medicine / Master / Doctor of Medicine

No description available.

Proefschrift--Universiteit Leiden, 2007. / Description based on print version record. Includes bibliographical references.

Thesis (D.P.E.)--Springfield College, 2002. / Includes bibliographical references.

Introduction: Toxoplasmosis is caused by infection with the protozoan Toxoplasma gondii (T. gondii), an obligate intracellular parasite. T. gondii infects a large portion of the world’s population, but uncommonly causes clinically significant disease. Those that are at greatest risk for more severe disease with toxoplasmosis are the immunologically impaired, fetuses, and newborns. T. gondii infection in immunocompetent patients can present as a self-limiting acute infection, or as an acute systemic disease. There are three main T. gondii genotypes, I, II, and III, with varying geographical prevalence. T. gondii is most commonly acquired via ingestion of infectious oocysts, from the environment, tissue cysts from contaminated food items, vertical transmission, or via organ transplantation from an infected donor. Diagnosis can be made via histological and serologic testing in suspected patients. Seropositive testing should be considered within the clinical context, as IgM antibodies may persist for months to years. IgG antibody avidity patterns further help delineate acute versus chronic infections. Histopathology from tissue biopsy of lymphadenopathy is more commonly pursued to establish diagnosis in immunocompetent patients. Case Report: We present a 37-year-old male who presented to the clinic with persistent bilateral non-tender occipital lymphadenopathy of two months duration. Patient also endorsed an acute fluid filled blister on the penis, recurrent cold sores, and significant fatigue. Review of systems were unremarkable. Patient’s immunizations were up-to-date. Patient is an active military serviceman with history of overseas deployment. Patient reports consuming undercooked meat overseas, as well as game meat preparation while hunting. Similar symptoms were also reported by another fellow veteran. Laboratory studies revealed normal CBC, CMP, and TSH. HIV, gonorrhea, and chlamydia testing were negative. Urology referral found no abnormalities. Aspiration biopsy of the right occipital lymph node demonstrated granulomas and aggregates of histiocytes compatible with reactive hyperplasia. Findings were suggestive of toxoplasmosis and no malignancy was found. Follow up T. gondii serological testing results revealed Ab IgM: 104 AU/ML (reference range 0.0-7.9). Toxoplasma gondii Ab IgG: >400 AU/ML (reference range 0.0-7.1), which were consistent for active infection. Patient was referred to Infectious Disease and supportive therapy was recommended. A three month follow up showed improvement in symptoms. Discussion: Although acute infections with T. gondii in immunocompetent patients typically are self-limiting, more serious systemic infections may occur. A pyrimethamine-containing antibiotic regimen is recommended for treating systemic infections. We propose educating high-risk individuals with appropriate preventive measures, which may be beneficial in preventing Toxoplasmosis.

Human herpesvirus type 6 (HHV-6) has been well described as an agent of meningoencephalitis in post-haematopoietic stem cell transplantation patients, but is a rare cause of meningoencephalitis in immunocompetent adults. We report an immunocompetent adult with HHV-6-associated meningoencephalitis. The patient was an elderly diabetic man who presented with fever and confusion, with cerebrospinal fluid (CSF) pleocytosis. HHV-6 DNA was amplified from CSF by polymerase chain reaction. In our review of the medical literature we examine clinical presentations, laboratory findings, neuroimaging studies, treatments and clinical outcomes in immunocompetent patients with HHV-6 meningoencephalitis.

A model for the study of the relationship of immunity to cancer is found in AKR mice which harbor Gross virus. This genetically transmitted virus is present in a latent form for months before it spontaneously induces leukemia. Many investigators have demonstrated near normal humoral responses, but abnormal cellular immunity in the preleukemic animal. With increasing age, pathology of the disease is expressed, reflecting diminished immunity. In this study, the ontogeny of humoral antibodies of AKR/J and SWR/J mice was assayed by microagglutination techniques in response to thymus-independent, thymus-dependent, and solubilized antigens. Simultaneous injections of thymusdependent and -independent antigens provided data suggesting an impaired humoral response in the AKR mouse.

Cat scratch's disease caused by Bartonella henselae, is known to be a self-limited benign process in immunocompetent children. The association with neurologic manifestations is very uncommon especially in patient with no immunologic defects and in cases without specific treatment. A 7 years old male patient, without any immunocompromised defect, presented an atypic presentation of the cat scratch disease. The patient came to the hospital in two opportunities in a status epilepticus, in both cases the diagnosis was encephalitis by Bartonella henselae and the evolution with treatment was monitored with PCR (polymerase chain reaction) in cerebrospinal fluid and blood, as well as IFI (IgM, IgG) serology (indirect immunofluorescence). The patient had a favorable clinical and laboratory evolution for 6 months showing no recurrence of the disease. / This work has been partially supported by the Programa Nacional de Innovacion para la Competitividad y Productividad ´ (Innovate Per ´ u), under the contract 116-PNICP-PIAP-2015.

Orientador: Alexandre Augusto Zaia / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-06T06:09:06Z (GMT). No. of bitstreams: 1 Almeida_JoseFlavioAffonsode_D.pdf: 2803790 bytes, checksum: 523bf1872c348721161eafd32bb6f736 (MD5) Previous issue date: 2006 / Resumo: Este estudo teve como objetivos identificar por técnica de imunohistoquímica linfócitos T4, linfócitos T8, linfócitos B, macrófagos e mastócitos em tecidos pulpares normais e inflamados de dentes humanos e correlacionar a presença dessas células com os sinais e sintomas apresentados pelos pacientes e aspectos clínicos dos dentes. Após a determinação do diagnóstico clínico das condições pulpares, 24 polpas normais e 18 polpas inflamadas foram coletadas de dentes extraídos clivados ou por extirpação em dentes que foram submetidos à endodontia. As polpas foram processadas histologicamente, sendo que uma secção tecidual de cada amostra foi corada por hematoxilina e eosina e as demais foram utilizadas para a imunohistoquímica. As lâminas foram analisadas em microscopia de luz. Cinco campos com maior intensidade de marcação foram capturados, tiveram suas áreas mensuradas e o número de células contado. Em polpas normais, os linfócitos T8 apresentaram maior número de células marcadas, seguidos pelos linfócitos T4, macrófagos, linfócitos B e mastócitos. Diferenças significantes foram encontradas, com maior número de linfócitos T8 quando comparados aos linfócitos B e mastócitos (Kruskal-Wallis - p< 0,05). Em polpas inflamadas, os macrófagos apresentaram maior número de células positivas seguidos dos linfócitos T8, T4, B e mastócitos. Não houve diferença estatística significante entre as densidades das células estudadas em polpas inflamadas (Kruskal-Wallis - p> 0,05). Dessa forma, concluiu-se que os linfócitos T4, T8 e B, macrófagos e mastócitos podem ser identificados em diferentes proporções nos tecidos pulpares normais e inflamados. Entretanto, não houve correlação entre a sintomatologia apresentada pelos pacientes e o aumento do número dessas células em todos os tecidos pulpares classificados clinicamente como inflamados / Abstract:The aim of this study was to identify by immunohistochemical technique T4 lymphocytes, T8 lymphocytes, B lymphocytes, macrophages and mast cells in normal and inflamed human dental pulps and to correlate the presence of these cells to the signals and symptoms presented by the patients and the teeth clinical aspects. After the clinical diagnoses, 24 normal dental pulps and 18 inflamed dental pulps were collected from extracted teeth or by extirpation during endodontic procedures. After dental pulp histological procedures, one tissue section from each specimen was stained with hematoxylin and eosin and the other sections were used to immunohistochemical analyses. The slides were analyzed by light microscopy. Five fields with more intensive immunostaining were captured, measured and the positive cells were counted. In normal pulps, T8 lymphocytes presented more positive cells followed by T4 lymphocytes, macrophages, B lymphocytes and mast cells. Statistical significance was founded with more T8 lymphocytes than B lymphocytes and mast cells (Kruskal-Wallis ¿ p< 0.05). In inflamed dental pulps, macrophages presented more positive cells, followed by T8, T4, B lymphocytes and mast cells. These data were not statistically significant (Kruskal-Wallis ¿ p> 0.05). It was concluded that T4, T8 and B lymphocytes, macrophages and mast cells could be identified with different rates in normal and inflamed dental pulps. However, no correlation was detected between the patient¿s symptomatology and these cells increase in all inflamed dental pulps / Doutorado / Endodontia / Doutor em Clínica Odontológica