The first-generation phosphodiesterase 5 inhibitors and their pharmacokinetic issue.

BACKGROUND: Erectile dysfunction (ED) is a relatively frequent disease that negatively impacts the overall quality of life, well-being, and relationships. Although the use of phosphodiesterase 5 inhibitors (PDE5is) has revolutionized the treatment of ED, a high percentage of ED patients discontinue PDE5i treatment. OBJECTIVES: (i) To analyze the reasons for patient dissatisfaction leading to PDE5i discontinuation; (ii) analyze the pharmacokinetics of new formulations focusing on the time needed to reach an effective plasma concentration of PDE5is (Tonset ) following drug intake; and (iii) summarize the physicochemical properties of sildenafil to understand which excipients may increase the absorption rate. MATERIAL AND METHODS: An online PubMed literature search was conducted to identify English language publications from inception to January 2019. RESULTS: The main reasons for patient dissatisfaction when using PDE5is on demand are the relatively long Tonset after taking vardenafil and sildenafil, including formulations such as film-coated tablets, fine granules, orally disintegrating tablets (ODTs), and oral thin films (ODFs). The relatively long Tonset , further worsened when accompanied by eating, highlights the following: (i) the need for planning intercourse, determining partner-related issues; (ii) issues when having sex before the maximum effect of the drug; and (iii) lower drug-related placebo effects. Some data suggest that sildenafil is a 'difficult' molecule, but Tonset can be improved following absorption by buccal mucosa using appropriate excipients. CONCLUSIONS: We conclude that several ODT and ODF formulations can improve the 'discretion' issue because they are taken without water, but they have similar pharmacokinetics to corresponding film-coated tablet formulations. One ODF formulation of sildenafil was characterized by a shorter Tonset and could potentially increase patient satisfaction following treatment. However, more clinical studies are needed to confirm the findings. Surfactants and ascorbic acid appear to be crucial excipients for achieving a high absorption rate, but more studies are needed.

Evaluation of intralesional injection of hyaluronic acid compared with verapamil in Peyronie's disease: preliminary results from a prospective, double-blinded, randomized study.

Several intralesional therapeutic protocols have been proposed for the treatment of Peyronie's disease. Among all, hyaluronic acid (HA) and verapamil have been differently tested. We aimed to evaluate the efficacy of intralesional verapamil (ILVI) compared with intralesional HA in patients with early onset of Peyronie's disease (PD). This is a multi-centre prospective double-arm, randomized, double-blinded study comparing ILVI vs. intralesional HA after 12-weeks. Sexually active men, older than 18 years and affected by the acute phase of PD were eligible for this study. Patients have been double-blinded randomly divided into two groups (1 : 1 ratio): Group A received intralesional treatment with Verapamil (10 mg in 5 mL of normal saline water) weekly for 12 weeks, while group B received intralesional treatment with HA (0.8% highly purified sodium salt HA 16 mg/2 mL) weekly for 12 weeks. The primary efficacy outcome was the change from the baseline to the endpoint (12 weeks after therapy) for the penile curvature (degree). The secondary outcome was the change in the plaque size and in the International Index of erectile Function (IIEF-5) score. The difference between post- and pre-treatment plaque size was -1.36 mm (SD ± 1.27) for Group A and -1.80 mm (SD ± 2.47) for Group B (p-value = NS). IIEF-5 increased of 1.46 points (SD ± 2.18) in Group A and 1.78 (SD ± 2.48) in Group B (p-value ± NS). No difference in penile curvature was observed in Group A, while in Group B the penile curvature decreased of 4.60° (SD ± 5.63) from the baseline (p < 0.001) and vs. Group A. According to PGI-I results, we found significant difference as concerning patient global impression of improvement (PGI-I) (4.0 vs. 2.0; p < 0.05). This prospective, double-arm, randomized, double-blinded study comparing ILVI vs. HA as intralesional therapy showed greater efficacy of HA in terms of penile curvature and PGI-I.

A kinetic model for predicting biodegradation.

Biodegradation plays a key role in the environmental risk assessment of organic chemicals. The need to assess biodegradability of a chemical for regulatory purposes supports the development of a model for predicting the extent of biodegradation at different time frames, in particular the extent of ultimate biodegradation within a '10 day window' criterion as well as estimating biodegradation half-lives. Conceptually this implies expressing the rate of catabolic transformations as a function of time. An attempt to correlate the kinetics of biodegradation with molecular structure of chemicals is presented. A simplified biodegradation kinetic model was formulated by combining the probabilistic approach of the original formulation of the CATABOL model with the assumption of first order kinetics of catabolic transformations. Nonlinear regression analysis was used to fit the model parameters to OECD 301F biodegradation kinetic data for a set of 208 chemicals. The new model allows the prediction of biodegradation multi-pathways, primary and ultimate half-lives and simulation of related kinetic biodegradation parameters such as biological oxygen demand (BOD), carbon dioxide production, and the nature and amount of metabolites as a function of time. The model may also be used for evaluating the OECD ready biodegradability potential of a chemical within the '10-day window' criterion.

Monitoring, modelling and environmental exposure assessment of industrial chemicals in the aquatic environment.

Monitoring and laboratory data play integral roles alongside fate and exposure models in comprehensive risk assessments. The principle in the European Union Technical Guidance Documents for risk assessment is that measured data may take precedence over model results but only after they are judged to be of adequate reliability and to be representative of the particular environmental compartments to which they are applied. In practice, laboratory and field data are used to provide parameters for the models, while monitoring data are used to validate the models' predictions. Thus, comprehensive risk assessments require the integration of laboratory and monitoring data with the model predictions. However, this interplay is often overlooked. Discrepancies between the results of models and monitoring should be investigated in terms of the representativeness of both. Certainly, in the context of the EU risk assessment of existing chemicals, the specific requirements for monitoring data have not been adequately addressed. The resources required for environmental monitoring, both in terms of manpower and equipment, can be very significant. The design of monitoring programmes to optimise the use of resources and the use of models as a cost-effective alternative are increasing in importance. Generic considerations and criteria for the design of new monitoring programmes to generate representative quality data for the aquatic compartment are outlined and the criteria for the use of existing data are discussed. In particular, there is a need to improve the accessibility to data sets, to standardise the data sets, to promote communication and harmonisation of programmes and to incorporate the flexibility to change monitoring protocols to amend the chemicals under investigation in line with changing needs and priorities.

[Urethral diverticuli in women: role of diagnostic methods in the preoperative assessment]. / Diverticoli uretrali nella donna: ruolo delle metodiche diagnostiche nell'inquadramento preoperatorio.

From 1985 to 1993 we observed 9 female patients with urethral diverticula. All patients underwent first clinical examination and then US (suprapubic and transrectal or transvaginal scans) and X-ray cystography which demonstrated the communication between the diverticula and the urethra, MRI was also performed, in order to explain the rapports between the diverticulum and the sphyncter. All patients underwent surgery and 8 were cured. No cases of incontinence were observed.

[Vesico-cutaneous fistula of the thigh as a late manifestation]. / Fistola vescico-cutanea della coscia a manifestazione tardiva.

Vesico-cutaneous fistulas rarely occur in the urinary tract (1.7% of all urinary fistulas). Trauma, neoplasias, inflammation and iatrogenic pathologies are among the principal causes. The external mouth of the fistula is usually found in the hypogastric area, scrotum, perineum and rarely elsewhere. This report describes the case of a 48 year old woman who, after severe trauma suffered bladder laceration, treated only with cystorraphy. Sepsis and gangrene followed involving the pubic area and the right thigh, associated with acute renal and adrenal gland cortex failure. After emergency treatment, the patient was discharged with an indwelling catheter. Ten months later she was referred to our urology clinic because of a suspected bladder-vaginal fistula. The indwelling catheter was removed and the bladder resumed functioning well. Six months later the external mouth of the fistula appeared on the right inner thigh. NMR confirmed the diagnosis of a vesico-cutaneous fistula. Surgery resolved the abnormality.

[Vesico-intestinal fistula in Crohn disease: the role of echography in its diagnosis]. / Fistole vescico-enteriche in corso di morbo di Crohn: ruolo dell'ecografia nella diagnosi.

Ultrasound is in widespread use in the study of gastrointestinal pathologies. In Crohn disease it is helpful in diagnosing complications such as thickening of the bowel loop walls, abscesses, lymph node enlargement and vesical-enteric fistulas. This report presents two cases in which vesical-enteric fistulas were visualized by US; confirming a diagnosis of Crohn's disease in one case, and diagnosing the fistula during the follow-up in the second patient in whom Crohn's disease had previously been diagnosed.