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The flow of the Greenland Ice Sheet is controlled by subglacial processes and conditions that depend on the geological provenance and temperature of the crust beneath it, neither of which are adequately known. Here we present a seismic velocity model of the uppermost 5 km of the Greenlandic crust. We show that slow velocities in the upper crust tend to be associated with major outlet glaciers along the ice-sheet margin, and elevated geothermal heat flux along the Iceland hotspot track inland. Outlet glaciers particularly susceptible to basal slip over deformable subglacial sediments include Jakobshavn, Helheim and Kangerdlussuaq, while geothermal warming and softening of basal ice may affect the onset of faster ice flow at Petermann Glacier and the Northeast Greenland Ice Stream. Interactions with the solid earth therefore control the past, present and future dynamics of the Greenland Ice Sheet and must be adequately explored and implemented in ice sheet models.

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BACKGROUND: Lymphadenectomy for rectal cancer, whether by open surgery or laparoscopy, is still a controversial subject. If we consider that approximately 20% of patients have nodal obturator metastases, then we must concede that extended lymphadenectomy is useless in the other 80% of patients. We set out to determine whether lymphoscintigraphy could show the lymphatic drainage from the cancer toward the obturator lymph nodes and thus help us to select the patients who would benefit by their removal. We also analyzed the possibility of applying the concept of the sentinel node to the treatment of rectal cancer. METHODS: Among 42 people who underwent laparoscopy for rectal cancer 11 patients with TNM stages T2-T3N0M0 were studied by CT & MRI, rectal ultrasonography, and lymphoscintigraphy with a colloidal injection of human albumin labeled with 99mTc at the base of the neoplasm. Afterward, the 11 patients underwent a lymphadenectomy that extended to the obturator nodes. RESULTS: In two patients, lymphoscintigraphy showed lymphatic drainage toward the obturator nodes. In one case, there were metastases. Lymphoscintigraphy did not show lymphatic drainage toward the obturator nodes in any of the other patients, and there were no metastases among them. It was not possible to identify a sentinel node. CONCLUSION: Lymphoscintigraphy can be used to select patients with rectal cancer who will be helped by a lymphadenectomy extended to the obturator nodes. However, the concept of the sentinel node cannot be applied to rectal cancer.

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BACKGROUND: Early node dissection offers increased survival in patients with node metastases only. The study of sentinel node (SN) using blue dye and radiolocalization permits to identify patients who could undergo lymphadenectomy. METHODS: At Department of Surgery of Macerata General Hospital 22 patients with melanoma of trunk or limbs at I and II stage were submitted to SN biopsy. RESULTS: SN was identified in all cases by combined approach. Dynamic lymphoscintigraphy permitted identification of SL when it was not the node nearest the tumor. Nodal metastases were found in 2 cases (9.1%) and the patients underwent regional lymphadenectomy. In 1 patient the SN was the only node with metastases. Both patients had high thickness melanomas. The measurement of radioactive exposition for operating room personnel and pathologist demonstrated that the technique is safe and without risks. CONCLUSIONS: Biopsy of SN is effective for identification of occult nodal metastases from cutaneous melanoma. Combined technique allows to localize SN in 100% of cases. There is not radio-exposition for operators.

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BACKGROUND: The purpose of this study is to emphasize the usefulness of combined intraoperative gamma-detecting-probe (C-Trak) and blue dye guided research of sentinel nodes (SN) in the treatment of cutaneous melanoma. METHODS: At the Department of General Surgery of Macerata Hospital, after informed consent, 22 consecutive patients (10 males and 12 females) with mean age 53 years (20-78 years) affected by histologically proved cutaneous malignant melanoma in stage I (TC, ultrasonography and bone scintigraphy) were studied by dynamic lymphoscintigraphy with 10.8-22.2 MBq of 99mTc albumin microcolloids 18-22 hours before surgery and by intradermal injection of blue dye at induction of anaesthesia. Intraoperative mapping technique to localize SN has been done by using a combination of a vital blue dye and a radioactive tracer. RESULTS: A total of 42 SN were identified. Micrometastases were found in 2 (9.1%) patients; 13 SN were well-coloured (31%), 23 SN were poorly-coloured (55%), and 6 SN were not coloured (14%). Overall localization with blue dye was 86%. All SN were radiolabeled, but identification with gamma detecting probe was possible only in 41 cases (95%). Combined techniques was effective in 100% of cases. CONCLUSIONS: Combined use of radiocolloids and blue dye is the gold standard for correct identification and biopsy of SN with 100% of favourable results. The technique is simple, fast and effective and permits to select the patients that need other surgical and oncologic procedures.

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Ketanserin is a pure and selective antagonist of serotonin S2-receptors in blood vessels, platelets and bronchial tissue. It antagonizes serotonin-induced vasoconstriction, bronchoconstriction and platelet aggregation, and indirectly it blocks platelet release reaction. Ketanserin has little or no effect on healthy subjects. Serotonin-induced or serotonin-potentiated platelet aggregation is inhibited in blood drawn from ketanserin-treated healthy volunteers. Oral or parenteral ketanserin treatment did not cause major changes in beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) plasma concentrations, when basic values were normal. Increased microaggregate formation was found in alcoholics and heavy drinkers. It was also found that beta-TG and PF4 levels were higher in these patients than in the controls. Ketanserin treatment tended to normalize these protein levels in such patients.

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In man, cholesterol esterification is controlled by lecithin:cholesterol-acyl-transferase (LCAT), which is a key-role enzyme of lipid metabolism. Though LCAT is synthesized by the hepatocytes, its activity seems to be linked to the kidney: in fact, LCAT activity is lowered in uremic and anephric subjects, and probably also in long-term haemodialysis patients. On the contrary, in successfull renal allografts we found fully restored LCAT activity. But physiopathological mechanisms underlying relationships between LCAT and kidney are still unclarified.

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LCAT activity is impaired in chronic renal failure. Our data show that LCAT activity is restored in successful renal transplant patients. Hence, relationship between kidney and LCAT activity can be postulated, but the underlying mechanisms are not yet fully clarified.

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