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Purpose: The precise determination of organ mass (mth) and total number of disintegrations within the thyroid gland (Ã) are essential for thyroid absorbed-dose calculations for radioiodine therapy. Nevertheless, these parameters may vary according to the method employed for their estimation, thus introducing uncertainty in the estimated thyroid absorbed dose and in any dose-response relationship derived using such estimates. In consideration of these points, thyroid absorbed doses for Graves' disease (GD) treatment planning were calculated using different approaches to estimating the mth and the Ã., Methods: Fifty patients were included in the study. Thyroid (131)I uptake measurements were performed at 2, 6, 24, 48, 96, and 220 h postadministration of a tracer activity in order to estimate the effective half-time (Teff) of (131)I in the thyroid; the thyroid cumulated activity was then estimated using the Teff thus determined or, alternatively, calculated by numeric integration of the measured time-activity data. Thyroid mass was estimated by ultrasonography (USG) and scintigraphy (SCTG). Absorbed doses were calculated with the OLINDA∕EXM software. The relationships between thyroid absorbed dose and therapy response were evaluated at 3 months and 1 year after therapy., Results: The average ratio (± 1 standard deviation) between mth estimated by SCTG and USG was 1.74 (± 0.64) and that between à obtained by Teff and the integration of measured activity in the gland was 1.71 (± 0.14). These differences affect the calculated absorbed dose. Overall, therapeutic success, corresponding to induction of durable hypothyroidism or euthyroidism, was achieved in 72% of all patients at 3 months and in 90% at 1 year. A therapeutic success rate of at least 95% was found in the group of patients receiving doses of 200 Gy (p = 0.0483) and 330 Gy (p = 0.0131) when mth was measured by either USG or SCTG and à was determined by the integration of measured (131)I activity in the thyroid gland and based on Teff, respectively. No statistically significant relationship was found between therapeutic response and patients' age, administered (131)I activity (MBq), 24-h thyroid (131)I uptake (%) or Teff (p ≥ 0.064); nonetheless, a good relationship was found between the therapeutic response and mth (p ≤ 0.035)., Conclusions: According to the results of this study, the most effective thyroid absorbed dose to be targeted in GD therapy should not be based on a fixed dose but rather should be individualized based on the patient's mth and Ã. To achieve a therapeutic success (i.e., durable euthyroidism or hypothyroidism) rate of at least 95%, a thyroid absorbed dose of 200 or 330 Gy is required depending on the methodology used for estimating mth and Ã.

Background: Thyroid follicular neoplasms (adenoma and carcinoma) may pose considerable difficulties to the differential diagnosis. Because such a distinction is not possible at fine-needle aspiration, surgery is often necessary. Clinical information such as age, sex, and node size is important in case of suspected carcinoma. Follicular carcinoma is characterized by capsular invasion, vascular invasion, and metastatic dissemination mainly by the hematogenic pathway. This invasion depends on collagen degradation in capsule and in subendothelial basement membrane. Collagen degradation has been widely researched in the angiogenesis process and in the hematogenic dissemination mechanism. In this study, we performed clinical and histopathologic assessment of 74 follicular neoplasms, as well as immunohistochemical reactions for CD-34 protein to estimate angiogenesis and for metalloproteinase-9, an enzyme that degrades type IV collagen., Methods: The research was carried out retrospectively in 74 patients who had surgery and were followed up at HC-FMUSP and IBCC. Clinical, histologic, and immunohistochemical variables were compared among the groups of follicular neoplasms and a control group of 36 patients with colloid goiter., Results: No significant statistical difference was found between patients with follicular adenoma and thyroid follicular carcinoma concerning sex (p =.092), age (p =.098), thyroid node size (p =.426), vascularization (p =.388), and immunostaining intensity for metalloproteinase-9 (p =.055). The proportion of immunoreactive cells for metalloproteinase-9 in follicular carcinoma cases was higher than that observed in follicular adenoma cases (p <.001). Patients in more advanced stages of carcinoma were more than 45 years old (p =.006), presented extensive invasion (p <.001), had less vascularization (p =.046), and a had higher proportion of immunoreactive cells for metalloproteinase-9 (p <.001)., Conclusions: The proportion of immunoreactive cells for metalloproteinase-9 in follicular carcinoma was higher than that observed in follicular adenoma, with a significant statistical difference (p <.001). This method must be developed to apply in material obtained by fine-needle aspiration to differentiate follicular adenoma from carcinoma., (Copyright 2000 John Wiley & Sons, Inc.)

We have previously shown that a low-stringency single-specific primer-polymerase chain reaction (LSSP- PCR) is a highly sensitive and reproducible technique for the genetic profiling of Trypanosoma cruzi parasites directly in tissues from infected animals and humans. By applying LSSP-PCR to the study of the variable region of kinetoplast minicircle from T. cruzi, the intraspecific polymorphism of the kinetoplast-deoxyribonucleic acid (kDNA) sequence can be translated into individual kDNA signatures. In the present article, we report on our success using the LSSP-PCR technique in profiling the T. cruzi parasites present in the hearts of 13 patients with chagasic cardiopathy and in the esophagi of four patients (three of them with chagasic megaesophagus). In two patients, one with the cardiodigestive clinical form of Chagas disease and the other with cardiopathy and an esophageal inflammatory process, we could study both heart and esophagus and we detected distinct kDNA signatures in the two organs. This provides evidence of a differential tissue distribution of genetically diverse T. cruzi populations in chronic Chagas disease, suggesting that the genetic variability of the parasite is one of the determining factors of the clinical form of the disease.

Background: Several tumor factors are associated with papillary thyroid cancer. Most studies do not compare the expressions of these factors in the primary tumors and in their associated cervical metastasis., Methods: Paraffin sections of 20 patients with papillary carcinoma of the thyroid gland with lymph node metastasis were studied. The presence and distribution of insulin-like growth factor I (IGF-I) and proliferating cell nuclear antigen (PCNA) was analyzed, through immunohistochemical technique, in both primaries and lymph node metastasis. The results were correlated with clinical-pathologic data (sex, age, size of primary, multicentricity, thyroid capsule invasion, lymphatic and blood vessels invasion, development of distant metastasis, and associated thyroid diseases)., Results: The qualitative analysis showed the reaction for IGF-I was present in more than 90% of the neoplastic cells in both primaries and lymph node metastasis. No correlation with the clinical-pathological features was observed. Regarding the PCNA, the mean percentage of nuclei stained showed no statistical difference between primaries and metastasis (p = 0.598). Except for age, clinicopathologic data had no influence on the mean percentage of nuclei stained. A correlation was verified between the percentage of cells stained by PCNA in primary tumors and the patients' age (p < 0. 01)., Conclusions: The expressions of these tumor factors are equally intense for both primary and metastatic tissue in papillary thyroid cancer. Despite the small size of the sample, the expressions of IGF-I and PCNA could not be associated to clinical-pathologic features, except for the age. As patients over 40 years old had higher expression of PCNA, this marker may have prognostic significance for patients with papillary thyroid cancer., (Copyright 1999 John Wiley & Sons, Inc. Head Neck 21: 723-727, 1999.)

Introduction: Meningococcal disease continues to warrant assessment as to its endemic and epidemic multicausality and temporal trends in various locations., Material and Method: Based on a standardization of epidemiological investigation of meningococcal disease in the municipality of Rio de Janeiro county, Southeastern Brazil, as from epidemic of the 1970s a study to characterized the epidemiological characteristics of the disease, was realized. The total of 4,155 cases reported between 1976 and 1994 were analyzed in a retrospective, descriptive, and analytical study, using the epidemiological investigation forms issued by the Municipal Health Secretariat. Statistical analysis was performed using the chi 2, Wilcoxon-Mann-Whitney, and Kruskal-Wallis tests., Results: The study resulted in the definition of three periods, classified as post-epidemic (1976-79), endemic (1980-86), and epidemic (1987-94), differentiated by the incidence rates and the predominant meningococcal serogroup. The mean incidence rates per period in the municipality were 3.51, 1.67, and 6.53 cases/ 100,000 inhabitants, respectively. Serogroups A and C predominated during the post-epidemic period, B and A in the endemic, and B in the epidemic., Conclusion: The mean case fatality rate remained virtually unchanged over time, but it varied by hospital, and during all three periods was lower in the State government reference hospital than in the other hospitals, whether public or private. The highest incidence and case fatality rates were associated with patients under one year of age, and the risk of acquiring the disease was greater among males. The highest incidence coefficients tended to occur in the same areas of the county during the three epidemiological periods, and the shanty-town population was at twice the risk of acquiring the disease.

Three children with acute schistosomiasis mansoni developed pyogenic liver abscesses. The abscesses were diagnosed by ultrasonography and confirmed during laparotomy. Staphylococcus aureus were the sole bacteria isolated from the abscesses. An experimental study was carried out in mice to establish whether schistosomiasis is a predisposing cause for pyogenic liver abscesses. Seventeen mice (group 1) were infected with 40 Schistosoma mansoni cercariae (LE strain) and 60 d later inoculated intravenously with a strain of Staph. aureus, isolated from a patient with bacteraemia; 17 mice infected with Sch. mansoni (group 2), 19 infected with bacteria alone (group 3), and 18 uninfected mice (group 4), served as controls. Thirteen group 1 mice (77%) developed multiple liver abscesses while none was observed in the controls. These results indicate that acute schistosomiasis mansoni concurrent with Staph. aureus bacteraemia favours the colonization of the liver by bacteria and the development of pyogenic hepatic abscesses.