Analysis of 161Tb by radiochemical separation and liquid scintillation counting.

The determination of 161Tb activity is problematic due to its very low fission yield, short half-life, and the complication of its gamma spectrum. At AWE, radiochemically purified 161Tb solution was measured on a PerkinElmer 1220 QuantulusTM Liquid Scintillation Spectrometer. Since there was no 161Tb certified standard solution available commercially, the counting efficiency was determined by the CIEMAT/NIST Efficiency Tracing method. The method was validated during a recent inter-laboratory comparison exercise involving the analysis of a uranium sample irradiated with thermal neutrons. The measured 161Tb result was in excellent agreement with the result using gamma spectrometry and the result obtained by Pacific Northwest National Laboratory.

Carcinosarcoma of the Female Urethra.

Carcinosarcoma is a rare malignant tumor with a biphasic morphology characterized by the presence of a malignant epithelial and mesenchymal component. It has been reported in many organs, including the genitourinary tract. We describe a case of a 47-year-old woman admitted to our hospital for history of recurrent urinary tract infection, dysuria and discharge of bloody fluid from the urethra at the end of urination. A tender palpable mass under the anterior vaginal wall was found and pathological examination showed a urethral carcinosarcoma. The histopathogenetic hypothesis and clinical management were considered in this report.

Isolated local recurrente of renal neoplasm with caval involvement 16 years after radical nephrectomy

OBJETIVOS: Presentar un caso de recurrencialocal de tumor renal 16 años después de nefrectomíaradical; analizar los datos de la literatura sobre tratamiento y pronóstico.MÉTODOS/RESULTADOS: Presentamos un caso de recurrencialocal asociado con trombosis de la vena cava que fue intervenido mediante resección en bloque del tumor y la vena cava con sustitución por una prótesis PTFE.CONCLUSIONES: La recurrencia local después de nefrectomíaradical es rara, siendo comunicada entre el 2-4% de los pacientes. Esta condición es incluso más rara después de diez años, especialmente si está asociada con trombosis de la vena cava.Se describe un caso de recurrencia local aislada de carcinoma de células renales con afectación de la cava 16 años después de nefrectomía radical. Pensamos que éste es el primer caso comunicado en la literatura. Este caso destaca la oportunidad de las revisiones periódicasde los pacientes sometidos a nefrectomía radical incluso muchos años después de cirugía

OBJECTIVE: To report a case of local recurrence 16 years after radical nephrectomy; to analyse literature data concerning, treatment and prognosis. METHODS/RESULTS: We report a case of local recurence associated with caval trombosis who was underwent an en–bloc resection of vena cava along with pericaval lesion and caval replacement with PTFE prosthesis. The Authors reviewed and analysed literature data. CONCLUSIONS: Local recurrence after radical nephrectomy is rare as it is reported only in 2-4% of patients. This condition is even rarer beyond 10 years especially if associated with caval trombosis. A case of isolated local recurrence of renal cell carcinoma with caval involvement 16 years after radical nephrectomy is described herein. To the best of our knowledge, this is the first case reported in literature. This case highlights the opportunity of a periodic check-up of patients submitted to radical nephrectomy, even many years after surgery

Isolated local recurrence of renal neoplasm with caval involvement 16 years after radical nephrectomy.

OBJECTIVE: To report a case of local recurrence 16 years after radical nephrectomy; to analyse literature data concerning, treatment and prognosis. METHODS/RESULTS: We report a case of local recurence associated with caval trombosis who was underwent an en-bloc resection of vena cava along with pericaval lesion and caval replacement with PTFE prosthesis. The Authors reviewed and analysed literature data. CONCLUSIONS: Local recurrence after radical nephrectomy is rare as it is reported only in 2-4% of patients. This condition is even rarer beyond 10 years especially if associated with caval trombosis. A case of isolated local recurrence of renal cell carcinoma with caval involvement 16 years after radical nephrectomy is described herein. To the best of our knowledge, this is the first case reported in literature. This case highlights the opportunity of a periodic checkup of patients submitted to radical nephrectomy, even many years after surgery.

[Unusual case of calcified renal fibroma]. / Un raro caso di fibroma renale calcifico.

The renal fibroma is an extremely rare event that takes its origin from parenchima, from the peri-renal tissues or from the renal capsule. A case of renal fibroma of a rarely met medullary origin is described.

Nitric oxide degradation of heparin and heparan sulphate.

NO is a bioactive free radical produced by NO synthase in various tissues including vascular endothelium. One of the degradation products of NO is HNO2, an agent known to degrade heparin and heparan sulphate. This report documents degradation of heparin by cultured endothelial-cell-derived as well as exogenous NO. An exogenous narrow molecular-mass preparation of heparin was recovered from the medium of cultured endothelial cells using strong-anion exchange. In addition, another narrow molecular-mass preparation of heparin was gassed with exogenous NO under argon. Degradation was evaluated by gel-filtration chromatography. Since HNO2 degrades heparin under acidic conditions, the reaction with NO gas was studied under various pH conditions. The results show that the degradation of exogenous heparin by endothelial cells is inhibited by NO synthase inhibitors. Exogenous NO gas at concentrations as low as 400 p.p.m. degrades heparin and heparan sulphate. Exogenous NO degrades heparin at neutral as well as acidic pH. Endothelial-cell-derived NO, as well as exogenous NO gas, did not degrade hyaluronan, an unrelated glycosaminoglycan that resists HNO2 degradation. Peroxynitrite, a metabolic product of the reaction of NO with superoxide, is an agent that degrades hyaluronan; however, peroxynitrite did not degrade heparin. Thus endothelial-cell-derived NO is capable of degrading heparin and heparan sulphate via HNO2 rather than peroxynitrite. These observations may be relevant to various pathophysiological processes in which extracellular matrix is degraded, such as bone development, apoptosis, tissue damage from inflammatory responses and possible release of growth factors and cytokines.

[Heredity in renal and prostatic neoplasia]. / L'ereditarietà nelle neoplasie renali e prostatiche.

There is an ever growing report of data supporting the evidence that accumulated genetic changes underlie the development of neoplasia. The paradigma of this multistep process is colon cancer were cancer onset is associated, over decades, with at least seven genetic events. The number of genetic alterations increases moving from adenomatous lesions to colon cancer and, although the genetic alterations occur according to a preferred sequence, the total accumulation of changes rather than their sequential order is responsible of tumor biological behavior. It is noteworthy that, at least for this neoplasia, carcinogenesis appears to arise as a result of the mutational activation of oncogenes coupled with the mutational inactivation of tumor suppressor genes. In some cases mutant suppressor genes appear to exert a phenotypic effect even when present in the heterozygous state thus been non "recessive" at the cellular level. The general features of this model may apply also to renal cell cancer (RCC) and prostate cancer (CaP). Extensive literature exists on the cytogenetic and molecular findings in RCC. Only 2% of RCC are familiar, but molecular genetic studies of these cancers have provided important informations on RCC pathogenesis. As with other cancers, familiar RCC is characterized by an early age of onset and frequent multicentricity. A pathological classification useful in studying these patients subdivide renal cancers in papillary (pRCC) and non papillary (RCC) neoplasms. The most common cause of inherited RCC is the Von Hippel Lindau disease (VHL) a dominantly inherited multisystem disorder characterized by retinal and cerebellar hemangioblastomas, pheochromocytomas, pancreatic cysts and RCC. Over 70% of these patients will develop an RCC by their sixth decade. In 1993 the isolation of the tumor suppressor gene in VHL disease at the level of chromosome 3p25-p26 have lead to a better understanding of RCC. Most missense mutations are associated with high risk of RCC, but some are associated with high risk of pheochromocytoma and low risk of RCC. The VHL gene is evolutionary conserved and encodes for a specific protein (pVHL). VHL protein downregulates transcriptional elongation and so suppresses the expression of proto-oncogenes and growth factors. Recently reintroduction of wild-type, non mutant, VHL gene into VHL deficient RCC cell line 786-O had no demonstrable effect on their in vitro growth but inhibited their ability to form tumors in nude mice. So far, VHL mutations or hypermethylations have been found in 76% of sporadic RCC. On the contrary, up to now, no 3p allele loss or VHL mutations have been detected in pRCC. Preliminary studies in familiar pRCC are pointing on genetic changes on chromosomes 1, 7, 16 and 17. As far as prostate cancer is regarded, men with a family history of prostate cancer have an age dependent, significantly increased PCa risk. For familiar clustering, of PCa the two main factors are early age at onset of the disease and the number of multiple affected family members. Hereditary prostate cancer is a subset of familiar prostate cancer with a pattern of distribution consistent with Mendelian inheritance. Hereditary prostate cancer is clinically defined as a clustering of 3 or more relatives within any nuclear family; or the occurrence of prostate cancer in each of 3 generations in either the probands paternal or maternal lineage; or a cluster of 2 relatives affected within 55 years of age or less. Therefore, hereditary prostate cancer may be seen as a multistep carcinogenesis, and clustering may be explained by Mendelian inheritance of a rare (frequency in population 0.36%) dominant, highly penetrant, allele. The estimated cumulative risk of developing PCa, is 88% for carriers as compared with 5% for non carriers. There are conflicting reports of an associated increased incidence of breast cancer in female relatives of men with familiar prostate cancer. In conclusion, there is a clear associatio

Suppression of endothelin-1 production in cultured human umbilical vein endothelial cells by heparin fractions separated by strong anion exchange chromatography.

Heparin has been shown to lower the production/secretion of the vasoconstrictive peptide endothelin-1. Endothelin-1 production is stimulated by thrombin, and it has been proposed that heparin binds to the anion-binding exosite of thrombin, preventing it from stimulating endothelin-1 production. To further test this proposal, heparin was fractionated by strong anion exchange chromatography (QAE-Sephadex A-25) into four fractions. These fractions had anticoagulant activities that increased linearly with charge, as defined by the median salt concentration needed for elution from the column. The fractions also differed in the total number of sulfates per mole of heparin, which was dependent on the molecular mass of the fractions rather than charge density. The fractions were found to significantly differ fron each other in their ability to suppress endothelin-1 production. The fraction eluting from the ion exchange column at the highest salt concentration had the greatest suppressive effect. Addition of sodium or potassium chloride to the media interfered with the ET-1 suppressive effect of unfractionated heparin, whereas lithium chloride had no effect. These data show that charge interactions between heparin and thrombin may be important in regulating the production of endothelin-1 and in regulating other thrombin-dependent functions.

Técnicas de exame psicológico: ensino, pesquisa e aplicaçöes em Säo Paulo / Psychological assessment techniques: teaching, research and applications in Säo Paulo

Faz um histórico sobre a pesquisa psicológica em Säo Paulo e relata algumas pesquisas relacionadas às técnicas de exame psicológico realizadas ao longo de sua carreira profissional como colaborador, pesquisador principal, pesquisador associado ou orientador de teses universitárias, nas diversas instituiçöes nas quais trabalhou

Abertura do "I encontro de tecnicas de exame psicologico: ensino, pesquisa e aplicacoes"

Considerando a oportunidade da realizacao deste I Encontro, o autor se refere a alguns dados historicos sobre a pesquisa psicologica em Sao Paulo e relata algumas pesquisas relacionadas as tecnicas de exame psicologico realizadas ao longo de sua carreira profissional como colaborador, pesquisador principal, pesquisador associado ou orientador de testes universitarios, em funcao das diversas instituicoes onde teve a ocasiao de trabalhar.

Specific heparin fractions suppress endothelin-1 production in cultured human umbilical vein endothelial cells.

Vascular endothelial cells produce endothelin-1, a peptide with potent vasoconstrictor and mitogenic properties. Heparin suppresses thrombin-stimulated endothelin-1 production in endothelial cells; this is consistent with its reported effect of lowering blood pressure. Since heparin is a heterogeneous mixture of glycosaminoglycans, we examined the effects of different fractions of heparin in suppressing endothelin-1 production in cultured endothelial cells. Heparin fractions differing in size and in antithrombin III affinity were prepared. The results show that the suppressive effect of heparin is independent of these properties of size and antithrombin III affinity. Heparin sulfate suppressed endothelin-1 production to a similar level as heparin. These experiments were conducted in a complete culture medium in the absence of added thrombin. To assess the role of endogenous thrombin in the medium on this process, we tested the effects of hirudin, a specific thrombin inhibitor peptide, on suppression of endothelin-1. Hirudin, like heparin, binds to the anion-binding exosite of thrombin. Hirudin alone, and combined with heparin, suppressed endothelin levels to the same extent as heparin. These experiments demonstrate that the suppressive effect of heparin is the result of its binding to the traces of thrombin in the culture medium, preventing stimulation of endothelin-1 production. This study supports the hypothesis that the functional thrombin receptor may participate in the stimulation of endothelin-1 by thrombin.

[Current developments on the physiology of the cardiac atrial pacemaker an excitation conduction of the left atrium]. / Aggiornamenti sulla fisiologia del "pacemaker" atriale cardiaco e sulla conduzione dell'eccitamento nell'atrio destro.

According to recent developments the atrial pacemaker area and the right atrium show a peculiar morpho-functional organization, i.e.: 1) The pacemaker area is formed of clusters of cells containing relatively few myofibrils and showing embryologic characteristics. Such cells are known as nodal cells and between these and the atrial muscles are in general situated transitional cells. Each cluster is separated from the other by collagenous boundaries. The resistance of the membranes to the current flow seems to be relatively low between the cells of the same cluster but the collagenous boundaries are, according to TRAUTWEIN e UCHIZONO (1963), very poor conductors. The pacemaker activity seems to originate inside the various clusters. 2) The functional relationships between the sinoatrial node and the atrioventricular node as well as the interatrial relationship would take place through preferential pathways. These pathways corresponding approximately to the tracts described by JAMES (1966) (anterior, posterior and middle internodal tracts) and to the interatrial or Bachmann bundle, seems to show a higher velocity conduction. In general the fibres of which the tracts are composed are neither morphologically nor functionally isolated from the atrial muscle. The functional consequences of the above mentioned nodal and atrial organization seems to be: a) The possible conditioning of the pacemaker functions by the various clusters activity i.e. the dominance of one cluster over another. b) The shifting of the pacemaker activity from one cluster to anothr due to the arrival of nervous stimuli or chemical substances, etc. According to some Authors as a consequence of the shift the pacemaker area can sometimes move out side the nodal tissue and settle inside an area belonging to the internodal pathways. c) Another consequence of the shift can be the different involvement of the conducting pathways which can lead to a change in the dynamics of the atrial invasion by the excitement.