Spironolactone improves lung diffusion in chronic heart failure.

AIMS: To evaluate whether anti-aldosteronic treatment influences lung diffusion (DLCO) in chronic heart failure (HF) patients. Spironolactone improves clinical conditions and prognosis in chronic HF and reduces connective tissue matrix turnover; DLCO abnormalities in chronic HF are related to increase in fibrosis and connective tissue derangement. METHODS AND RESULTS: Thirty stable chronic HF patients, with reduced DLCO (<80% of predicted), were randomly assigned to active treatment (25 mg spironolactone daily) or placebo in addition to conventional anti-failure treatment. They were evaluated by quality of life questionnaire, laboratory investigations, cardiopulmonary exercise test, and pulmonary function test, which included DLCO and membrane diffusing capacity (DM). The evaluation was done before treatment and 6 months after. Quality of life score and standard pulmonary function tests were not significantly affected by spironolactone, while active treatment increased DLCO due to an increase of DM (DLCO: 18.3+/-3.9 vs. 19.9+/-5.5 mL/min/mmHg; DM: 28.1+/-7.7 vs. 33.3+/-8.6 mL/min/mmHg) and peak oxygen consumption (peak VO2 16.8+/-1.9 vs.18.6+/-2.2 mL/min/kg). Increments of DLCO and peak VO2 were linearly related (R=0.849, P<0.001). CONCLUSION: These data show a positive effect of spironolactone on gas diffusion and exercise capacity suggesting a novel mechanism by which anti-aldosteronic drugs improve HF clinical condition and prognosis.     

Erectile dysfunction: from biochemical pharmacology to advances in medical therapy

Research on penile smooth muscle physiology has increased the number of drugs available for treating erectile dysfunction (ED). Penile erection involves the relaxation of smooth muscle in the corpus cavernosum. The key mediator of smooth muscle relaxation is nitric oxide (NO), which acts by increasing the cellular level of cGMP. Another cyclic nucleotide, cAMP, is involved in smooth muscle cell relaxation; cAMP formation is stimulated by a number of compounds, such as alprostadil. An increase in cAMP and/or cGMP levels can also be induced by inhibition of phosphodiesterases (PDEs), the enzymes involved in cyclic nucleotide breakdown. Both papaverine and sildenafil are PDE inhibitors. Papaverine is a non-specific inhibitor of these enzymes; sildenafil is an orally active, potent and selective inhibitor of GMP-specific PDE5, the predominant isoenzyme metabolizing cGMP in the cells of the corpus cavernosum. Penile smooth muscle contraction, induced by adrenergic fibers through alpha(1) adrenoceptors, produces detumescence, thus making alpha adrenoceptor antagonists suitable for maintenance of penile erection. The orally active drug yohimbine is a mixed alpha(1)-alpha(2) adrenoceptor antagonist that works by a dual mechanism; it facilitates sexual arousal by acting on alpha(2) adrenoceptors in the central nervous system and blocks adrenergic influences at peripheral level.     

Multivariate analysis of the influence of peri-implant clinical parameters and local factors on radiographic bone loss in the posterior maxilla: a retrospective study on 277 dental implants

Clinical Oral Investigations - The aim of the present study was to investigate whether peri-implant clinical parameters (modified plaque index (mPI), bleeding and/or suppuration on probing (B/SOP))...     

Biological tooth replacement and repair

Implantology is an ancient art that can be traced back several thousand years. Although modern implants have improved substantially over the last 50 years, the basic principle remains unchanged: replace a missing tooth with an inert non-biological material (metal, ceramic etc.). The rate of technological improvements in implants has reached a plateau and substantial new developments will require major changes to the basic approach. Rapid advances in the development of cell-based therapies in medicine suggest that similar approaches should be considered in dental treatment. The use of cell-based implants that will develop into natural teeth and the employment of cells to restore/repair caries lesions is thus an area of considerable interest and excitement.     

A preliminary investigation on the occurrence of protozoa in swimming pools in Italy

In Italy controls on the hygienic quality of swimming pools are fixed by the Accordo tra il Ministero della Salute, le regioni e le province autonome di Trento e di Bolzano, come into force in 2003. In the present study swimming pools were investigated from the microbiological point of view on the basis of the new legislation. Contemporaneously, for the first time in Italy, analytical controls on the occurrence of the protozoa Cryptosporidium and Giardia were performed with both techniques of immunofluorescence and polymerase chain reaction. Results evidenced a good water quality when the bacterial parameters stated by law were considered. However in some swimming pools, the protozoa were also recovered. Factors affecting the use of molecular techniques on the analysis of environmental samples are also put into evidence.     

Daily profile of circulating C-type natriuretic peptide in pre-ascitic cirrhosis and in normal subjects: relationship with renal function

OBJECTIVE: To investigate whether the C-type natriuretic peptide (CNP) has a role in the regulation of fluid and sodium homeostasis in normal subjects and in pre-ascitic cirrhotic patients. MATERIAL AND METHODS: The daily profile of CNP plasma levels was assessed by serial measurements (0700 h, 0900 h, 1800 h, 2300 h) in 10 pre-ascitic cirrhotic outpatients (age 56+/-4 years) and in 10 age-matched healthy controls (54+/-2 years) on a normal sodium diet (150 mmol/day) while carrying on their usual activities (mobile from 0700 h to 2200 h), after an equilibration period of 5 days. Daily diuresis and natriuresis were also monitored. RESULTS: Mean daily CNP was comparable in cirrhotic and healthy subjects (3.64+/-0.32 versus 3.20+/-0.20 pg/ml; p=0.139); CNP concentration showed a tendency towards a circadian fluctuation in healthy subjects (p=0.053) but not in patients (p=0.171). Mean daily CNP concentration significantly correlated with 24-h natriuresis (r=0.709; p=0.022) and urine volume (r=0.745; p=0.013) in patients but not in healthy subjects. CONCLUSIONS: CNP plasma levels appear to play a role in the water-sodium balance regulation in patients with pre-ascitic cirrhosis.