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Objective: Dynamic renal scintigraphy complemented by late gravity assisted postvoid images to 60 minutes is a frequently used diagnostic test in the evaluation of hydrone- phrosis. The objective of this study is to evaluate the effectiveness in acquiring images at 180 minutes to calculate the late output fraction (LOF) of 99mTc-DTPA in the diagno- sis of ureteropelvic junction obstruction (UPJO). Materials and Methods: A retrospective study of 177 patients (196 renal units) of sus- pected cases of clinical UPJO was conducted. The patients were submitted to at least two dynamic renal scintigraphies of 99mTc-DTPA, with the addition of furosemide (F0), with a mean age of 4.3±3.8 years for the first study, and a follow-up of 2.7±2.5 years. Results: For diagnosis based on renal curves, a 100% sensitivity, 82.2% specificity, positive predictive value (PPV) of 10.4% and negative predictive value (NPV) of 100% were estimated. For diagnosis based on LOF, a 100% sensitivity, 96.3% specificity, PPV of 35.7% and NPV of 100% were estimated. Conclusion: A LOF

Background Radiosurgery has been widely used to treat cerebral AVMs, providing angiographic evidence of obliteration of the malformation in 80% to 95% of patients, after a latency period of 2 to 5 years. Case Description We describe a case of hemorrhage, 6 years after radiosurgery and 4 years after complete angiographic obliteration of an AVM that had not previously bled and that persisted angiographically, obliterated after bleeding. Results Several treatment options have been reported for patients with completely obliterated AVMs that bled, including conservative treatment, repeated radiosurgery, and open surgery with resection of AVM remnants. In the present case, the decision to perform surgery based on the probable association of the enhancing area observed on the MRI and the histologic findings was finally confirmed. Conclusions Magnetic resonance imaging enhancement areas on the obliterated AVMs may have a histopathologic correlation with persistence of permeable vessels and can be used as a guide for surgery and postoperative control. The follow-up of angiographically obliterated AVMs that bleed remains a matter of discussion twofold: regarding timing and use of a proper diagnostic test.

Peritonitis is a surgical problem with a high mortality rate attributable to various complications, including respiratory infection. This complication is more common under certain conditions reflective of the origin of peritonitis, suggesting that the composition of the peritoneal fluid exerts an influence on the intensity of the macrophage and peritoneal response. To establish a correlation among macrophage function, absorption of bacteria from the peritoneal cavity, and the pH of the peritoneal fluid, we carried out this study.Thirty female Wistar rats were divided into three equal groups, all of which received infusions of 0.9% saline by parietal puncture. In group A (control), the saline pH was 7.0; in group B, it was 2.5; and in group C, it was 8.5. After 40 min, 0.25 mL of a suspension containing 10(11) colony-forming units of (99m)Tc-labeled Escherichia coli was infused by the same route. After another 40 min, samples of vena caval blood, spleen, liver, and lung were removed; the radioactivity was counted; bacterial absorption was determined; and the proportional radioactivity/g of tissue was calculated. The values were compared among the groups by the Student t-test, with the level of significance set at p0.05.There was significantly greater bacterial absorption in group B than in group C (p = 0.004) but no differences in the numbers of bacteria in the liver and spleen. Bacteria were significantly more numerous in the peripheral blood in group B than in groups A and C (p = 0.04 for both). Pulmonary phagocytosis was significantly reduced in group B compared with group A (p = 0.008) and group C (p = 0.005).Peritonitis associated with acidic conditions in the peritoneal cavity is correlated with a reduction in pulmonary phagocytosis and an increase in the numbers of nonphagocytized bacteria in the peripheral blood, possibly representing a direct or indirect cause of the higher incidence of pneumonia and sepsis in these individuals.

Anti-amastigote polyclonal antibody (IgG) was incubated with solutions of stannous chloride and sodium borohidride. After that, 3.7 MBq of technetium-99m (99mTc) was added. A labeling yield of the antibody about 84% was obtained. After filtration of 99mTc-IgG, the radiochemical purity increased from 84 to 95%. The labeling of IgG with 99mTc did not modify the immunoreactivity of the antibody, since it was able to identify in vitro and in vivo the specific antigen of Leishmania amazonensis.

The association between Helicobacter pylori infection and gastric motility abnormalities is still controversial, partly because of the lack of an appropriate animal model. H. heilmannii type 1 (Hh1), a spiral bacterium that infects the stomach of both man and pigs, easily colonises and induces an inflammatory response in the gastric mucosa of rodents. For these reasons, the present study investigated the relationship between gastric motility in rats experimentally infected with Hh1 and correlated the results with serum gastrin and gastric somatostatin concentrations, as these hormones seem to be involved in gastric motility. Ten rats were inoculated with gastric mucus from an Hh1-positive pig and 10 animals with gastric mucus from an Hh1-negative pig (control group). After 56 days, gastric emptying was studied in vivo by scintigraphy. The animals were then killed, blood samples were collected for serum gastrin measurement, strips of the gastric wall were obtained for an in-vitro motor study and fragments of the gastric antrum were obtained for somatostatin content evaluation, Hh1 diagnosis and histological study. There was a significant increase in gastric emptying in the test group compared with the controls as demonstrated by the in-vivo and in-vitro studies. Serum gastrin levels were significantly higher and somatostatin levels were lower in the test group than in the controls. In addition, infected animals showed evidence of gastritis on histological examination. Gastric motility is altered in rats infected with Hh1, a fact possibly related to concurrent abnormalities of gastrin and somatostatin secretion.

Samples of a culture of unlabeled Escherichia coli were incubated with different concentrations of stannous chloride for various time periods. 99mTc (26.0 MBq) was added to each preparation and the results showed a labelling yield of 98% for E. coli. Since the bacterial viability of 99mTc-E. coli and E. coli did not show any statistical differences, these results demonstrate that labelling of E. coli with 99mTc does not modify the bacterial viability, and the radiolabelled bacteria may be a good model to study bacterial translocation.

The case is presented of a 21 year-old male with a history of left proptosis and diplopia of two weeks of onset. The MRI showed an ethmoid-orbital vascular lesion with anterior skull base invasion and orbital extension. Biopsy of the ethmoid confirmed fibrovascular tissue, which supported the diagnosis of angiofibroma.It is a benign neoplasm with local characteristics of malignancy due to its ability to invade adjacent areas. In this case, the debut presented with manifestations of orbital extension. A broad and multidisciplinary approach is needed in order to improve prognosis.

Biofilm formation on external ventricular drainages (EVDs) has been postulated as the main pathogenic mechanism for EVD-associated ventriculitis. However, biofilm on EVDs has never been systematically studied and the in vivo effect of antibiotic-impregnated EVDs on biofilm has not been assessed. The aim of this study was to measure the prevalence of biofilm formation on EVDs and to analyze the influence of antibiotic-impregnated EVD on the risk of biofilm formation and ventriculitis. Consecutive patients with EVDs were included in the study. Surveillance cerebrospinal fluid (CSF) cultures were performed twice a week. Withdrawn EVDs were cultured using standard bacteriologic techniques and examined under a scanning electron microscope. We collected 32 EVDs, 18 of which (56 %) were antibiotic-impregnated EVDs. Biofilm was present on 24 EVDs (75 %), ventriculitis was diagnosed in 6 patients (19 %), and colonization occurred in 12 patients (38 %). All cases of ventriculitis were due to Gram-negative bacteria. Biofilm was more frequent on EVDs originating from patients with ventriculitis or bacterial colonization. Impregnated EVDs did not avoid ventriculitis or colonization, but biofilm development on these devices depended on the time from insertion and varied from 67 % for those used for

we report the clinical, radiological and pathological features of a spinal pleomorphic xanthoastrocytoma, an unusual neoplastic entity in a really rare location, establish an appropriated management of these lesions and review the short available english literature.a 60 years old woman consulted with doctor because she felt progressive clumsiness accompanied by occasional paresthesias on her left hand. Neurological examination showed up weakness and slight propioceptive disturbances. The differential imagine diagnosis was established between intramedullary astrocytoma and ependimoma. Patient underwent surgical gross total remove. Histopathological examination confirmed the diagnosis of pleomorfic xanthoastrocytoma. We performed MRI controls at 6, 12, 24 and 36 months that did not reveal recurrence. Nowadays, the patient has regained her previous quality of life.comparing to published cases about intracranial pleomorphic xanthoastrocytomas, spinal pleomorphic xanthoastrocytomas (SPXA) present different epidemiological characteristics. The known SPXAs affected to cervical and/or high thoracic levels. The hypothesis about a more aggressive behaviour of PXA in spinal cord may be corroborated after literature review. Extension examination is mandatory since dissemination along the neuroaxis has been described. Removal extension is crucial in the prevention of tumour recurrence. Adyuvant radiotherapy should only be considered when there is postoperative residual tumour and/or anaplastic features. Randomized clinical trials or databases are necessary to know all the aspects of this pathological entity.

AIM: To evaluate inflammatory activity in patients with Crohn’s disease (CD) using technetium-99m-hexamethylpropyleneamine oxime (99mTc-HMPAO) granulocyte scintigraphy. METHODS: Twenty patients (7 male and 13 female) with CD and five healthy volunteers were selected for 99mTc-HMPAO granulocyte scintigraphy. The Crohn’s Disease Activity Index (CDAI), blood tests and C-reactive protein (CRP) of each patient were performed 7 d before the scintigraphic images. The leukocytes were labeled according to the International Society of Radiolabeled Blood Elements (ISORBE) consensus protocol and the scintigraphic images, including single photon emission computed tomography, were obtained 30 min and 2 h after injection of the radiolabeled leukocytes. RESULTS: The labeling yield of the leukocytes with the lipophilic complex 99mTc-HMPAO was 55.0% ± 10%. Six of the 20 patients (30%) presented congruent results for the three parameters investigated (CDAI, Scintigraphic Index and CRP). On the other hand, 14 patients (70%) did not show congruent results. There was no significant correlation between the indices analyzed according to the Spearman test (P > 0.05, n = 20). CONCLUSION: The results suggest that 99mTc-HMPAO-labeled leukocyte scintigraphy could be important for determining inflammatory activity in CD even in the absence of clinical symptoms.

Technetium-99m (99mTc) has been the radionuclide of choice for nuclear medicine procedures and experimental research. Because of its optimal nuclear properties, 99mTc is suitable for high efficiency detection with the advantage of reduced radiological waste. Crotalus venom (CV) has been shown to reduce tumors in clinical studies and tissue distribution studies are very important for clinical use. The goal of this work was to obtain CV labeled with 99mTc which preserves its biological activity. After labeling, biological activity was assessed by hemolytic activity evaluation. Labeled and crude venom caused indirect hemolysis provided that the incubation medium contained an exogenous source of lecithin. High yield radiolabeled-CV was obtained and biological activity was preserved. The results suggest that 99mTc-CV can be a useful tool for biodistribution studies.Tecnécio-99m tem sido o radioisótopo de escolha para procedimentos médicos e pesquisas experimentais. Em decorrência de suas propriedades nucleares, 99mTc é adequado para detecção de alta eficiência com a vantagem do baixo risco radiológico. O veneno de Crotalus (CV) apresentou propriedades antitumorais em estudos clínicos e estudos de biodistribuição são fundamentais em pesquisas clínicas. Esse trabalho teve como objetivo obter um análogo de veneno de Crotalus marcado com 99mTc que preservasse sua atividade biológica. Após a marcação, a atividade biológica foi avaliada através do ensaio de atividade hemolítica. Veneno nativo e marcado apresentaram atividade hemolítica indireta quando incubados em um meio contendo uma fonte exógena de lecitina. Obteve-se um alto rendimento de marcação e a atividade biológica das moléculas foi preservada. Nossos resultados sugerem que 99mTc-CV pode representar uma ferramenta muito útil para estudos de biodistribuição.

Objectives: The purpose of the study was toevaluate the outcome of prenatally detectedureteropelvic junction obstruction (UPJO)managed with a more conservative protocol.Methods: The records and imaging studies of 77consecutive neonates with UPJO identified by fetal hydronephrosis werereviewed. A nonoperative approach wasattempted in patients with mild/moderate pelvicdilatation, renal units with good functionas ascertained by DMSA scan and anon-obstructed pattern on DTPA. Otherwise, thepatients were managed surgically bypyeloplasty. Both groups were prospectivelyfollowed and the imaging studies were performedbefore and after the initial approachand at one-year intervals thereafter.Results: Of the 77 infants (85 units), 39 weresubmitted to surgery (33 pyeloplasty and 7 nephrectomy) and 38 were conservativelymanaged. During follow-up, 9 (24%) of 38 patients in the non-operative group presentedrenal function deterioration and 3 presented with urinary infections and were submitted topyeloplasty. Of the 39 patients surgically managed, 76% presented improvement ofhydronephrosis and 90% showed a non-obstructed pattern on diuretic renography. Thedifferential renal uptake, as measured by DMSA scan, remained stable in the three groupsanalyzed (conservative, initial pyeloplasty, and delayed pyeloplasty). Therewas a minimal improvement in those units submitted to pyeloplasty with impairedrenal function at baseline (< 40%). Mean renal uptake was 28.6% at admission and33.9% at the end of follow-up. Conclusion: There was a wide spectrum ofureteropelvic junction stenosis. Surgical intervention in a subgroup of patients withsevere hydronephrosis and impaired function may possibly improve or preserve renalparenchyma. Conversely, conservative management and clinical follow-up are safe anddesirable for the subgroup with mild/moderate pelvic dilatation and preservedrenal function.

As alterações imunitárias que ocorrem durante a gravidez são ainda pouco compreendidas. Para determinar a influência da gravidez na atividade fagocitária do sistema mononuclear fagocitário (SMF) foram utilizadas vinte ratas adultas. Os animais foram divididos em dois grupos (n-10): Grupo 1 - controle, Grupo 2 - ratas prenhas. A função do sistema mononuclear fagocitário foi determinada pela captação de enxofre coloidal marcado com 99mTc pelos órgãos do SMF, além de avaliar a permanência do radiofármaco em coágulo sangüíneo. O peso e a radiação de cada amostra foram medidas. Realizou-se também análise histológica desses órgãos. Os resultados foram comparados pelo teste t de Student. Em todos os animais, a captação do radiofármaco foi maior no fígado, seguido pelo baço e pulmão. O coágulo sangüíneo apresentou uma quantidade mínima de radiação. As ratas grávidas registraram menor captação do colóide no fígado e maior captação no pulmão em relação ao grupo controle. Não foram evidenciadas alterações na histoarquitetura desses órgãos. Em rata grávida, a atividade fagocitária do SMF diminuiu no fígado, porém aumentou no pulmão. Alterations of the immune function during the pregnancy are not well understood. To assess the influence of pregnancy on the phagocytic function of the reticuloendothelial system twenty adult female rats were divided into two groups: Group 1 (n=10) - control, Group 2 (n=10) - pregnant rats. The assessment of the phagocytic function of the reticuloendothelial system was by the uptake of sulphur colloid labeled with Tc99m by the reticuloendothelial system organs as well as to assess the permanence of the radio isotope in blood clots. The weights and radioactive levels of the samples were measured. Histologic analyses of these organs were performed as well. The results were compared using the Student t-test, with significance at p

We studied 13 children with 21-hydroxyalse deficiency to explore the immediate potential suppressive effect of hydrocortisone dose schedule on the adrenal cortex. They were given 20 mg/m2 daily in a controlled trial. After random administration of a greater dose in the morning (7 patients) or at night (6 patients), we measured plasma levels of 17-hydroxyprogesterone, testosterone, and androstenedione at times-24, 0, 2, 4, and 6h. Considerable fluctuation of the steroid levels, unrelated to the drug intake, was observed. There was no statistically significant differences between the “morning dose” and “night dose” groups for any steroid. We conclude that; (i) the greater night dose did not avoid the 17-hydroxyprogesterone morning peaks, and (ii) the variation in plasma steroid levels is so marked that a single morning sample is unreliable to reflect the degree of adrenal suppression.