Losartan decreases glomerular filtration rate in isolated perfused porcine slaughterhouse kidneys.

We investigated whether Losartan, an angiotensin II (Ang II) AT1 receptor antagonist, decreases renal vascular resistance (RVR) and increases glomerular filtration rate (GFR) in isolated perfused porcine slaughterhouse kidneys (11 control experiments and 11 Losartan experiments with 7.5mg Losartan in the preservation solution and 100(g/minute Losartan infused during perfusion). With perfusion, plasma renin activity (PRA) increased markedly from 3 +/- 1 to 90 +/- 17 ng Ang I/ml/h (control), and from 4 +/- 1 to 70 +/- 8 ng Ang I/ml/h (Losartan), plasma Ang II increased from 86 +/- 63 to 482 +/- 111 pg/ml (control), and from 73 +/- 42 to 410 +/- 91 pg/ml (Losartan). The GFR was decreased in Losartan experiments as compared with control experiments (5 +/- 1 versus 10 +/- 2 ml/min/100g kidney wt; p < 0.05). The RVR was the same in both groups (0.2 +/- 0.01 mm Hg/100g kidney wt/min/ml). Tubular sodium reabsorption was decreased in Losartan experiments as compared with control experiments (0.7 +/- 0.1 versus 1.4 +/- 0.3 mmol/min/100g kidney wt). Overall, Losartan accentuated pathophysiological signs of acute renal failure. Although other drugs have to be investigated, these results suggest that porcine slaughterhouse kidneys could be useful as a tool for research in areas such as transplantation and intensive-care medicine.

Impact of sentinel lymph node biopsy in patients with Merkel cell carcinoma: results of a prospective study and review of the literature.

PURPOSE: Merkel cell carcinoma (MCC) is the most aggressive of the cutaneous malignancies, showing a propensity to spread to regional lymph nodes (LNs). The aim of this prospective study was to examine the feasibility and clinical impact of sentinel lymph node biopsy (SLNB) in this cutaneous malignancy. METHODS: The study population comprised 23 patients with stage I MCC (median age 70 years, range 50-85 years). Lymphoscintigraphic mapping with( 99 m)Tc-nanocolloid was performed in all patients. Sentinel lymph nodes (SLNs) were identified, excised and analysed in serial sections by conventional histopathology and cytokeratin-20 immunohistochemistry. RESULTS: Metastatic disease was determined in the SLNs of 11 patients (47.8%). Elective lymph node dissection (ELND) was performed in eight of these 11 patients, four of whom had additional positive LNs. During follow-up (median 36.1 months, range 3-79 months), seven of the 23 patients (30%) relapsed: four had a local recurrence and three, in-transit metastases. Recurrence developed in two SLN-negative patients with local LN metastases and in one SLN-positive patient with distant metastases. This patient died, representing the only tumour-related death in our sample. Median survival was 49.1 and 35.5 months for SLN-negative and SLN-positive patients, respectively. This difference was not statistically significant (p=0.3452). CONCLUSION: SLNB allows for exact nodal staging in patients with MCC. Whether additional ELND is of further benefit remains unclear.

Subareolar injection of technetium-99m nanocolloid yields reliable data on the axillary lymph node tumour status in breast cancer patients with previous manipulations on the primary tumour: a prospective study of 117 patients.

According to recently published guidelines, histological clarification by interventional techniques should be undertaken before planning the surgical management of patients with breast carcinoma. In patients with previous manipulations on the primary tumour, peritumoural injection in the context of preoperative scintigraphic detection of the sentinel lymph nodes is not possible. The aim of this prospective study was to clarify whether subareolar injection of nanocolloid can yield reliable data on the axillary lymph node tumour status in breast cancer patients with previous manipulations on the primary tumour. To date, 117 women (age 31-80 years) with breast carcinoma have been enrolled. All of these patients had undergone a biopsy (n=88) or surgery on the primary tumour (n=29) and were without clinical suspicion of lymph node metastases. Subareolar injection of 40 MBq technetium-99m nanocolloid was carried out in at least eight deposits around the areolar margin [one deposit in the middle of each quadrant and one deposit at each quadrant intersection (0.05 ml/deposit)]. Immediately after injection, dynamic and static lymphoscintigraphy of the axillary, thoracic and cervical areas was performed in various views with a gamma camera (LEAP collimator, 256x256 matrix). Lymphatic drainage was directed exclusively to the ipsilateral axilla. Sentinel lymph node biopsy and elective dissection of axillary lymph nodes were performed in all patients. All lymph nodes removed were examined by histology and immunohistochemistry. In 26 patients, lymph node metastases were found in the sentinel lymph nodes. In six of them, non-sentinel lymph nodes also showed tumour involvement. In the remaining 91 patients, lymph node metastases could be found neither in sentinel lymph nodes nor in non-sentinel lymph nodes. In conclusion, subareolar nanocolloid injection can yield reliable information on the axillary lymph node tumour status in patients with previous manipulations on the primary tumour in the breast.