The single photon emission microscope (SPEM) is an instrument developed to obtain high spatial resolution single photon emission computed tomography (SPECT) images of small structures inside the mouse brain. SPEM consists of two independent imaging devices, which combine a multipinhole collimator, a high-resolution, thallium-doped cesium iodide [CsI(Tl)] columnar scintillator, a demagnifying/intensifier tube, and an electron-multiplying charge-coupling device (CCD). Collimators have 300- and 450-µm diameter pinholes on tungsten slabs, in hexagonal arrays of 19 and 7 holes. Projection data are acquired in a photon-counting strategy, where CCD frames are stored at 50 frames per second, with a radius of rotation of 35 mm and magnification factor of one. The image reconstruction software tool is based on the maximum likelihood algorithm. Our aim was to evaluate the spatial resolution and sensitivity attainable with the seven-pinhole imaging device, together with the linearity for quantification on the tomographic images, and to test the instrument in obtaining tomographic images of different mouse organs. A spatial resolution better than 500 µm and a sensitivity of 21.6 counts·s-1·MBq-1 were reached, as well as a correlation coefficient between activity and intensity better than 0.99, when imaging 99mTc sources. Images of the thyroid, heart, lungs, and bones of mice were registered using 99mTc-labeled radiopharmaceuticals in times appropriate for routine preclinical experimentation of <1 h per projection data set. Detailed experimental protocols and images of the aforementioned organs are shown. We plan to extend the instrument's field of view to fix larger animals and to combine data from both detectors to reduce the acquisition time or applied activity.

É descrita a correlação anatomopatológica de um paciente usuário de drogas injetáveis com talcose sistêmica acometendo pulmões, pleuras, fígado, baço e linfonodos e que desenvolveu hipertensão arterial pulmonar e cor pulmonale. Destaca-se o fato de que apesar do uso crônico de drogas injetáveis e outros comportamentos de alto risco para infecção pelo retrovírus, o paciente era HIV negativo, não apresentava linfocitopenia, nem alterações histopatológicas compatíveis com AIDS à necropsia.

Anatomo-pathological correlation in a case of systemic talc granulomatosis affecting lungs, pleura, liver, spleen and mesenteric lymph nodes resulting in pulmonary arterial hypertension and cor pulmonale is described. The patient, a 26-year-old male HIV-negative intravenous drug addict had no lymphopenia or any histopathologic findings at necroscopy compatible with AIDS, despite of a chronic high-risk behavior favoring this illness.

Foram analisados retrospectivamente 500 prontuários de pacientes transplantados renais no período de 1968 a 1991, sendo identificados 9 casos de Nocardiose; 7 do sexo masculino e 2 do sexo feminino. A idade mediana destes pacientes foi de 33 anos e a infecção ocorreu nos primeiros 6 meses em 6 pacientes, havendo relação direta com pulsoterapia em apenas um paciente. Manifestações pulmonares ocorreram em 100% dos casos, sendo que os sintomas mais frequentes foram febre, tosse e dor pleural. As alterações radiológicas observadas compreenderam infiltrados nodulares em 55% e abcessos em 22% dos casos. Houve disseminação para a pele em 3 pacientes, para o SNC em 4 pacientes, e 1 paciente apresentou, além de comprometimento pulmonar, pericardite por Nocardia. Em nossa casuística o diagnóstico foi post-mortem em 30% dos casos e a mortalidade foi de 77%. Km 3 pacientes, cujo diagnóstico foi precoce, houve resposta satisfatória ao tratamento instituído. As infecções por Nocardia apresentam bom prognóstico quando diagnosticadas a tempo, sendo portanto necessário um alto grau de suspeição, principalmente em pacientes imunossuprimidos com acometimento pulmonar, neurológico ou cutâneo.

In the present report the authors discuss the diagnostic difficulties, therapeutic measures and the clinical course of Nocardia infection which occurred among renal transplant recipients at the University Hospital of the Faculty of Medicine of Ribeirão Preto, University of São Paulo (UH-FRP), from 1968 to 1991. Among 500 individuals submitted to renal transplant, 9 patients developed Nocardiosis at varying times after transplant (two months to over two years). All the patients had pulmonary involvement and their most common symptoms were fever, cough and pleural pain. Dissemination of the process is common and three patients presented cutaneous abscesses, four CNS involvement and one had pericarditis due to Nocardia. The diagnostic is quite difficult since there is no specific clinical picture, concomitant infections are frequent and the microorganism presents slow growth in culture (ranging from four to forty days, in our experience). In this report, three cases were only diagnosed by necropsy. The treatment of choice is a combination of Sulfamethoxazole and Trimethoprim (SMX-TMP). In the present series, overall mortality was 77% (7 cases) and in five of the patients who died the diagnosis was late. All the patients who had CNS involvement died.