Rapidly involuting congenital haemangioma: diagnostic and therapeutic approach regarding two case reports.

Two unrelated neonates were born with a large purplish congenital mass of the thigh and forearm. Both showed signs of heart dysfunction, and one of them had anaemia and thrombocytopenia. The imaging assessment of the lesions showed well-defined subcutaneous solid masses with an exuberant vascular component. Both were kept under surveillance and maintenance therapy. A progressive dimensional reduction of the lesions supported the diagnosis of rapidly involuting congenital haemangioma (RICH). RICH is a rare vascular tumour that presents as a congenital purplish bulky mass. The diagnosis depends on the clinical evaluation of the lesion and the imaging characterisation of its solid components and vascular network. RICH may be complicated by high-output heart failure, anaemia and thrombocytopenia. Despite its exuberant presentation, it undergoes involution in the first year of life; therefore, early invasive therapies should be avoided. It is essential to detect any dimensional increase, suggesting more aggressive diagnoses, such as kaposiform haemangioendothelioma.

The ingestion of a Nectandra membranacea extract changes the bioavailability of technetium-99m radiobiocomplex in rat organs.

The radiobiocomplexes labeled with technetium-99m (Tc-99m) have been widely used in nuclear medicine in single photon emission computed tomography and in basic research. The aim of this study was to assess the influence of a Nectandra membranacea extract on the bioavailability of the sodium pertechnetate (Na(99m)TcO(4)) radiobiocomplex in rat organs. The animals were treated with a N. membranacea extract (30 mg/ ml), for 6 days. Na(99m)TcO(4) was injected, the organs were isolated and weighed, and the radioactivity was determined in each organ (%ATI/organ). The %ATI/organ was divided by the mass of each organ to calculate the %ATI/g. A significant increase of the %ATI/organ of Na(99m)TcO(4) was observed in muscle and thyroid as well as in the %ATI/g in the heart, kidney and thyroid. These findings could result from the interaction between components of the plant extract and the radiobiocomplex which may influence the uptake Na(99m)TcO(4) in rat organs. Therefore, precaution is suggested in the interpretation of nuclear medicine results in patients using this herb.

The ingestión of a Nectandra membran cea extract changes the bioavailability of technetium-99m radiobiocomplex in rat organs

The radiobiocomplexes labeled with technetium-99m (Tc-99m) have been widely used in nuclear medicine in single photon emission computed tomography and in basic research. The aim of this study was to assess the influence of a Nectandra membran cea extract on the bioavailability of the sodium pertechnetate (Na99mTc0(4)) radiobiocomplex in rat organs. The animals were treated with a N. membran cea extract (30 mg/ ml), for 6 days. Na99mTc0(4) was injected, the organs were isolated and weighed, and the radioactivity was determined in each organ ( percentATI/organ). The percentATI/organ was divided by the mass of each organ to calculate the percentATI/g. A significant increase of the percentATI/organ of Na99mTc0(4) was observed in muscle and thyroid as well as in the percentATI/g in the heart, kidney and thyroid. These findings could result from the interaction between components of the plant extract and the radiobiocomplex which may influence the uptake Na99mTc0(4) in rat organs. Therefore, precaution is suggested in the interpretation of nuclear medicine results in patients using this herb.

Down-regulation of p300/CBP histone acetyltransferase activates a senescence checkpoint in human melanocytes.

The histone acetyltransferases p300 and cAMP-responsive element-binding protein-binding protein (CBP) are required for the execution of critical biological functions such as proliferation, differentiation, and apoptosis. Both proteins are believed to regulate the activity of a large number of general and cell-specific transcription factors. Here we demonstrate a dramatic decrease in the total cellular levels of p300 and CBP with increasing population doublings of human normal melanocytes. We show that one consequence of p300 depletion is transcriptional down-regulation of the cyclin E gene, caused by deacetylation of histones at its promoter. The cyclin E promoter was activated by p300 and the histone deacetylase inhibitor trichostatin A. Conversely, the cyclin E promoter was repressed by wild-type Retinoblastoma tumor suppressor p105 protein (pRB) and by a dominant negative p300 mutant (DN p300) that lacks histone acetyltransferase activity. We also provide evidence of the alternative recruitment of p300 and histone deacetylase 1 to the cyclin E promoter in proliferating and senescent melanocytes, respectively. The biological significance of these results was established by showing that block of p300 activity by overexpression of DN p300 or by Lys-CoA, a specific chemical inhibitor of p300, resulted in growth inhibition, down-regulation of cyclin E, and activation of the senescence-associated beta-galactosidase marker in human melanocytes and melanoma cells. Together, these results provide evidence for the essential role of p300 in the regulation of proliferation and senescence in cells from melanocytic origin.