The haemostatic efficacy and foreign body reaction of epinephrine-Impregnated polyurethane foam in osseous defects.

The objective of this study was to compare the haemostatic efficacy and foreign body reaction of epinephrine-impregnated cotton pellets with those of epinephrine-impregnated polyurethane (PU) foam cubes in osseous defects created in guinea pigs. Initially, these substances were randomly applied to the osseous defects in guinea pigs for 2 min and blood loss was measured. The animals were then sacrificed 7 weeks later and the degree of foreign body reaction was scored. The data were analysed by the independent-samples Kruskal-Wallis test. Epinephrine-impregnated PU foam cubes showed significantly better haemostatic effect compared to epinephrine-impregnated cotton pellets. The PU foam containing epinephrine specimens elicited significantly less foreign body reaction compared to epinephrine cotton pellets (P < 0.05). Based on the results of this study, it is concluded that epinephrine-impregnated PU foam cubes are a good alternative to epinephrine-impregnated cotton pellets as a local haemostatic agent in endodontic surgery.

Relationship between serum testosterone and nocturia in men without benign prostate enlargement.

Recent studies have focused on the relationship between nocturia and serum testosterone because testosterone is thought to be an important factor of prostate growth. However, it remains unclear whether altered serum concentrations of testosterone is associated with an increased risk of nocturia because patients who were taking diuretics or who had a large prostate, which may precipitate nocturia, were not excluded from most previous studies. We analyzed the clinical records of 596 non-benign prostatic enlargement (BPE) male patients to explore the relationship between serum total testosterone and nocturia. All patients were evaluated using a serum prostate-specific antigen (PSA) assay, measurement of serum total testosterone, transrectal ultrasonography, uroflowmetry, and a compilation of the International Prostate Symptom Score (IPSS) and International Index of Erectile Function (IIEF) questionnaires. Nocturia was defined as ≥2 nocturnal voiding episodes. The number of nocturia episodes was assessed using IPSS question 7. To evaluate the effect of serum testosterone on nocturia, multivariate regression analysis was performed including the covariates of age, IPSS, IIEF score, body mass index, PSA, prostate volume, and maximal urine flow rate. Based on multivariate linear analysis, serum testosterone level was not significantly associated with the severity of nocturia. However, with regard to the relationship between prevalence of nocturia and serum testosterone, prevalence of nocturia was significantly positively associated with age (OR = 1.048, p = 0.005), total IPSS (OR = 1.217, p < 0.001), and testosterone level (OR = 1.150, p = 0.041). Therefore, in men without an enlarged prostate, testosterone may play an opposing role in the etiology of nocturia.

Effect of levitra on sustenance of erection (EROS): an open-label, prospective, multicenter, single-arm study to investigate erection duration measured by stopwatch with flexible dose vardenafil administered for 8 weeks in subjects with erectile dysfunction.

To investigate the change of erection duration measured by stopwatch with flexible dose vardenafil administered for 8 weeks in subjects with erectile dysfunction (ED). Effect of levitra on sustenance of erection was an open-label, prospective, multicenter and single-arm study designed to measure the duration of erection in men with ED receiving a flexible dose of vardenafil over an 8-week treatment period. Patients were instructed to take vardenafil 10 mg 60 min before attempting the intercourse. Vardenfil could be increased to 20 mg or decreased to 5 mg concerning patients' efficacy and safety. Following the initial screening, patients entered a 4-week treatment-free run-in phase and 8-week treatment period, during which they were instructed to attempt intercourse at least four times on four separate days. A total of 95 men were enrolled in 10 centers. After the 8 weeks treatment, the mean duration of erection leading to successful intercourse was statistically superior when patients were treated with vardenafil. After an 8-week treatment, the duration of erection leading to successful intercourse was 9.39 min. There were significant benefits with vardenafil in all domains of International Index of Erectile Function. Secondary efficacy end points included success rate of penetration, maintaining erection, ejaculation and satisfaction were superior when patients were treated with vardenafil. There was a significant correlation between duration of erection with other sexual factors. Also partner's sexual satisfaction was increased with vardenafil. Most adverse events were mild or moderate in severity. Vardenafil was safe and well tolerated. Vardenafil therapy provided a statistically superior duration of erection leading to successful intercourse in men with ED with female partner.

The relaxation effect and mechanism of action of higenamine in the rat corpus cavernosum.

Higenamine mediates cardiotonic, vascular relaxation and bronchodilator effects. The relaxation effects and the mechanism of action of higenamine on the rat corpus cavernosum (CC) were assessed to investigate the effect of higenamine on penile erection. Strips of CC and aorta were used in organ baths for isometric tension studies. Tension was measured with isometric force transducers, and muscle relaxation was expressed as the percent decrease in precontraction induced by phenylephrine (PE). The relaxation reactions were investigated in an endothelial-denuded group and groups pretreated with N(G)-nitro-L-arginine methyl ester (NO synthesis inhibitor), propranolol (ß-receptor blocker), indomethacin (COX inhibitor), glibenclamide (K(+)(ATP) channel inhibitor), 4-aminopyridine (membrane potential-dependent potassium channel inhibitor) and methylene blue (guanylyl cyclase inhibitor) for 30 min. Intracavernous pressure (ICP) was assessed in rats after the intravenous administration of higenamine, and changes in guanosine 3',5'-cyclic monophosphate and adenosine 3',5'-cyclic monophosphate (cAMP) concentrations were measured on the basis of the higenamine concentration. Also, the combined reaction of higenamine and the phosphodiesterase type-5 (PDE-5) inhibitors was assessed. Higenamine induced relaxation of the CC and the aortic strips precontracted with PE in a dose-dependent manner. The CC was significantly more relaxed than the aortic rings in response to the same higenamine concentration (P<0.05). The CC relaxation reaction was suppressed by the ß-receptor blocker propranolol. The cAMP concentration increased gradually with increased higenamine concentration (P<0.05). The ICP also increased with increased higenamine concentration in vivo (P<0.05). In the group pretreated with 10(-7) M higenamine, the relaxation reaction of CC induced by the PDE-5 inhibitor increased significantly, compared with CC exposed to the PDE-5 inhibitor but not pretreated with higenamine (P<0.05). In conclusion, higenamine induced relaxation of the rat CC in a dose-dependent manner. The effect may be mediated through ß-adrenoceptors. The results suggest that higenamine may be valuable as a new lead compound for treating erectile dysfunction.

Comparison of cadaveric pericardial, dermal, vein, and synthetic grafts for tunica albuginea substitution using a rat model.

OBJECTIVE: To evaluate in an animal model the intermediate and long-term efficacy of cadaveric pericardium, dermis, vein and Gore-Tex per thousand as grafting materials for tunica albuginea substitution after plaque excision for Peyronie's disease. MATERIALS AND METHODS: The study comprised 100 male Sprague-Dawley rats (300-325 g) divided into five equal groups: group 1, sham-operated controls; and groups 2-5 which underwent wedge excision of the tunica albuginea and replacement with either cadaveric pericardium, dermis, vein or Gore-Tex grafts. Ten rats in each group had the cavernosal nerve stimulated electrically to assess erectile function at 4 months, and the remaining 10 rats at 6 months. After death the sampled tissues were fixed in 10% formalin, paraffin-embedded, and stained with Masson's trichrome and Verhoff's van Giesen for collagen and elastic fibres. RESULTS: Erectile function, assessed by cavernosal nerve stimulation, did not differ significantly in any of the groups (P > 0.05). The histological assessment of penile cross-sections showed minimal fibrosis surrounding the patch in the dermal and vein grafts, and moderate to severe fibrosis in the Gore-Tex graft at 4 and 6 months. In the pericardial graft there was a moderate degree of fibrosis at 4 months with only minimal fibrosis at 6 months. CONCLUSIONS: These results show that cadaveric pericardium allows complete penile expansion and is strong enough to withstand normal intracorporal pressures. There was minimal fibrosis in the pericardial, dermal and vein grafts, and moderate fibrosis in the Gore-Tex graft at 6 months. The pericardial graft is a satisfactory grafting material when used for tunica albuginea substitution, including the surgical management of Peyronie's disease.

Evaluation of nitric oxide synthase and arginase in the induction of a Peyronie's-like condition in the rat.

Peyronie's disease is an idiopathic, localized connective tissue disorder of the penis, involving the tunica albuginea of the corpus cavernosum and adjacent areolar space. Current proposals as to the origin of Peyronie's disease suggest that fibrosis and collagen changes of the tunica are the result of an inflammatory process following vascular trauma. Our laboratory and other investigators have recently proposed an animal model for the study of Peyronie's disease. When transforming growth factor-beta1 (TGF-beta1) was injected into the rat tunica albuginea, tissue fibrosis was observed at 6 weeks. Therefore, our aim was to assess arginase II, endothelial and inducible nitric oxide synthase isoforms, and nitrotyrosine levels--all factors involved in inflammatory reactions--in the cavernosal tissue of saline-injected and TGF-beta1-injected rats after 6 weeks in order to evaluate the roles these enzymes may play in the induction of a Peyronie's-like condition in the rat. To examine the expression of endothelial nitric oxide synthase (eNOS), iNOS, and arginase II protein, and mRNA in the corpus cavernosum, immunoblot analysis, and reverse transcriptase-polymerase chain reaction were performed. We also determined immunohistochemically the expression of nitrotyrosine, a marker of peroxynitrite formation, in the rat penis. After 6 weeks, iNOS protein and gene expression was up-regulated and eNOS protein and gene expression was down-regulated in the corpora cavernosa of the TGF-beta1-injected penises. Furthermore, arginase II protein expression as well as immunohistochemical localization of nitrotyrosine was significantly higher in the TGF-beta1-injected corpora cavernosa. These results suggest that iNOS is the key control element for peroxynitrite formation, arginase II expression, and eNOS down-regulation in the induction of a Peyronie's-like condition in the rat.

Expression of gonadotropin-releasing hormone (GnRH) and GnRH receptor mRNA in prostate cancer cells and effect of GnRH on the proliferation of prostate cancer cells.

The purpose of this study was to determine the production of gonadotropin-releasing hormone (GnRH), the co-occurrence of GnRH receptors in prostate cancer cells, and the effect of GnRH on prostate cancer cell proliferation. Four human prostate cancer cell lines were studied. LNCaP is an androgen sensitive prostate cancer cell line, DU-145 and PC-3 are androgen resistant, and TSU-Pr1 is uncharacterized. The expression of GnRH and GnRH receptor mRNAs were assessed by in situ hybridization and the effect of exogenous GnRH on proliferation of prostate cancer cells was measured by thymidine incorporation assay. GnRH mRNA expression, determined by in situ hybridization, was found in 83.48% of the LNCaP, 89.7% of the TSU-Pr1, 86.2% of the PC-3 and 95.3% of the DU-145. Signals of GnRH receptor mRNA were detected in more than 95% of the cells of all four cell lines. The proliferation of the prostate cancer cells grown in media supplemented with peptide hormone lacking charcoal-stripped serum was significantly (P < 0.05) suppressed. No significant effect of GnRH on the proliferation of all four prostate cancer cells was observed. In summary, prostate cancer cells produced GnRH and its receptors, and exogenous GnRH treatment did not affect the prostate cancer cell proliferation. The existence of GnRH and GnRH receptor mRNA in the same cell suggests that the role of GnRH produced by prostate cancer cells would be autocrine.

Stage specific identification of the expression of GnRH mRNA and localization of the GnRH receptor in mature rat and adult human testis.

PURPOSE: To identify the expression of gonadotropin-releasing hormone (GnRH) messenger ribonuclueic acid (mRNA) and localize GnRH receptors in mature rat and adult human testes. MATERIALS AND METHODS: In situ hybridization and enzymatic receptor binding localization were performed. RESULTS: GnRH mRNA was expressed within the seminiferous tubules in both mature rat and adult human testis. In rats, expression of GnRH mRNA was identified in the Sertoli cells and spermatogenic cells of some seminiferous tubules, but the other tubules did not express any hybridization signal. In humans, expression of GnRH mRNA was identified only in some spermatogenic cells in some seminiferous tubules. The receptors for GnRH were localized to cells in the interstitial tissues of the testis, probably Leydig cells. CONCLUSION: The authors believe that the mature rat and adult human seminiferous tubular cells produce GnRH at the same specific stage of the spermatogenic cycle and that GnRH produced within seminiferous tubules, including Sertoli cells and spermatogenic cells, reacts with neighboring GnRH receptors in interstitial cells, including Leydig cells. The GnRH produced from the Sertoli cells in seminiferous tubules would react with GnRH receptors in interstitial cells as a paracrine hormone.