Nuclear medicine in the treatment of endocrine and neuroendocrine tumors

Radionuclide therapy plays an important role in the treatment of endocrine and neuroendocrine tumors. Therapy with 131I is used in patients with papillary and follicular thyroid carcinoma for ablation of thyroid remnants and for treatment of distant metastases. In neck recurrence, 131I may be used as monotherapy or in combination with surgery. Both radioimmunotherapy and 90Y-DOTATOC are being applied in non-131I-avid thyroid malignancies such as medullary thyroid carcinoma. 131I-MIBG is currently used in various treatment schedules for recurrences and metastases of neuroblastoma, pheochromocytoma, paraganglioma and carcinoid. In neuroblastoma 131I-MIBG can be given upfront to reduce large and bulky tumors for subsequent surgery, chemotherapy and autologus bone marrow infusion. In carcinoid and other neuroendocrine tumors therapy with radiolabelled somatostatin analogues appears to be a promising modality. Radiopharmaceutical quality requirements, patient preparation, radiation protection and hospital isolation facilities are important supportive factors to enable adequate radionuclide therapy

Permeabilization and in situ adsorption studies during growth and coumarin production in hairy root cultures of Cichorium intybus L.

Effect of addition of a permeabilizing agent dimethyl sulfoxide (DMSO) and a solid adsorbent, XAD -7, on growth and coumarin production in hairy root cultures of C. intybus was studied. Continuous permeabilization of the hairy root cultures of C. intybus with DMSO has been shown to be an effective strategy for enhanced release of coumarins while preserving the root viability. DMSO at 0.2% (v/v) level showed the maximum growth and coumarin production but was less as compared to control on day 28. Treatment of cells with increasing concentrations of DMSO (0.3 - 0.6 % v/v) to hairy root cultures of C. intybus, showed an inverse relationship with growth and coumarin production. Growth and production of coumarins increased with 1% media filtrate (MF) of cultures of Phytopthora parasitica var. nicotiana treatment. It was observed that treatment with DMSO (0.2% v/v) and 1% MF of P. parasitica showed the better growth and coumarin production with an increased release of coumarins as compared to the control and other treatments. It was observed that treatment of hairy root cultures with XAD-7 resulted in lesser growth and coumarin production as compared to control during the culture period. Addition of XAD-7 along with 1% MF of P. parasitica showed enhanced growth, coumarin production and increased adsorption as compared to control and lone XAD-7 treatment. Combined addition of DMSO/XAD-7 with fungal elicitor showed synergistic response in terms of biomass and coumarin production. Excretion of coumarins in both the cases was dependent on the presence of DMSO/XAD-7. These results showed that continuous permeabilization of hairy root cultures of C. intybus by using DMSO at 0.2% (v/v) level coupled with 1% MF of P. parasitica maintained viability of tissues and produced coumarins at higher level.