Proteinase-activated receptor-1 (PAR-1) activation contracts the isolated human renal artery in vitro.

1. The in vitro motor function of protease-activated recepter-1 (PAR-1), PAR-2 and PAR-4 and the presence by immunohistochemistry of PAR-1 in the human renal artery have been investigated. 2. Thrombin and the human PAR-1 (SFLLRN-NH(2)) activating peptide, but not the PAR-1 reverse peptide (NRLLFS-NH(2)), contracted both endothelial-intact and endothelial-denuded human renal artery strips, whereas no relaxation was observed either in strips non-precontracted or precontracted with phenylephrine. Maximum contraction by thrombin or SFLLRN-NH(2) was about 60% of phenylephrine. However, thrombin was approximately 1000-fold more potent than SFLLRN-NH(2). 3. PAR-1 desensitisation, using repeated applications of SFLLRN-NH(2), almost completely blocked the response to thrombin. The contractile effect produced by thrombin and SFLLRN-NH(2) was not affected by nitric oxide synthase inhibition, but was significantly reduced by cyclooxygenase blockade. 4. Trypsin, the PAR-2 (SLIGKV-NH(2) and SLIGRL-NH(2)) and PAR-4 (GYPGQV-NH(2) and AYPGKF-NH(2)) activating peptides did not produce any significant contraction or relaxation. 5. In agreement with the motor function data immunohistochemistry showed specific staining patterns for PAR-1 in the human renal artery. 6. Combined, these studies would suggest a possible role for PAR-1 in renal vascular homeostasis.

[Role of transrectal ultrasonography in prostatic brachytherapy]. / Ruolo dell'ecografia transrettale nella brachiterapia prostatica.

UNLABELLED: The rationale for interstitial brachytherapy (seed implant) is based on the principle that dissipation of radiation energy in tissues decreases exponentially as the square of source would receive maximal doses of radiation, there will be a rapid fall-off the dose in surrounding normal tissues. Over the years, a range of isotopes have been tested, and the technique have evolved from free-hand implantation to ultrasound guided template system. MATERIALS AND METHODS: From September 2001 to March 2002 we treated 17 patients with clinically localized prostatic cancer. For seed implantation we used the transrectal ultrasound guided implantation of 125I source. Isodose distributions are provided at each 5 mm increment throughout the treatment volume to determine the precise localization of seed placement. RESULTS: 23.5% of patients developed acute urinary retention, 11.8% incidence of transurethral resection after 6 months and 0% incidence of urinary incontinence. Longer follow-up will be necessary for biochemical failure. CONCLUSIONS: Permanent interstitial implantation should be limited to patients with early stage disease with favourable prognostic features. The use of transrectal ultrasound as diagnostic system as guided implantation is the most popular approach even in experienced hands.