Aliskiren: a new inhibitor of renin-angiotensin aldosterone system activity.

The importance of renin-angiotensin aldosterone system (RAAS) in cardiovascular and renal diseases has long ago been recognized. However despite the availability of many effective drugs, such as angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers, RAAS blockade is incomplete in several patients with consequent uncontrolled high blood pressure and not efficacy cardiovascular and renal protection. Aliskiren is a new renin inhibitor that block the RAAS at its origin. Recent studies suggest that Aliskiren reduces blood pressure, inhibits plasma renin activity and attenuates renal damage in diabetic patients with nephropathy. This review summarized the results of the more important studies performed in hypertensive and diabetic patients in which Aliskiren showed to be a safe and effective antihypertensive agent that can be used in monotherapy or in combination with other drugs to provide additional options to improve blood pressure control.

Renal effects of dual renin-angiotensin-aldosterone system blockade in patients with diabetic nephropathy.

Evidence from recent studies indicates that in patients with diabetic nephropathy combined therapy with ACE inhibitors (ACEI) and AT1-receptor antagonists (ARB) results in more complete blockade of the renin-angiotensin-aldosterone system (RAS) than monotherapy, and reduces proteinuria. Most of these trials, however, had short follow-up, included a small number of patients, and were heterogeneous, so the opportunity to start this treatment in these patients remains unclear. This review summarizes the results of these studies, describing the renal effects of dual RAS blockade in both type 1 and type 2 diabetic patients.

Effectiveness of different techniques for removing gutta-percha during retreatment.

AIM: To evaluate the effectiveness of various techniques for removing filling material from root canals in vitro. METHODOLOGY: Eighty extracted mandibular premolar teeth were selected for the study. The teeth were root filled using thermomechanical compaction of gutta-percha. After 8 months, the filling material was removed and canals were reinstrumented using the following techniques: group I - hand instrumentation with K-type files (SybronEndo, Orange, CA, USA); group II - K3 Endo System (SybronEndo); group III - M4 system (SybronEndo) with K-type files (SybronEndo); and group IV - Endo-gripper system (Moyco Union Broach, York, PA, USA) with K-type files (SybronEndo). The amount of filling debris remaining on root canal walls was assessed radiographically; the images were digitized and analysed using AutoCAD 2000 software. Total canal area, area of the cervical, middle and apical thirds, and area of remaining filling material were outlined by one operator. The ratios between these areas were calculated as percentages of remaining debris. Thereafter, data were analysed by means of one-way anova and the post-hoc Duncan test to identify differences between the four techniques. RESULTS: Multiple comparisons of the percentages of remaining filling material in the entire canal did not reveal any significant differences between the methods of removal. However, when each third was analysed separately, significant differences for remaining debris were present between groups. The apical third had the most remaining material, whilst the cervical and middle thirds were significantly cleaner (P = 0.002). Comparison of the techniques revealed that teeth instrumented with K3 rotary instruments had a lower ratio of remaining filling material in the apical third (P = 0.012). CONCLUSION: In the apical third, K3 rotary instruments were more efficient in removing gutta-percha filling material than the other techniques, which were equally effective for the other thirds.

Grand unification of quark and lepton flavor changing neutral currents.

In the context of supersymmetric grand unified theories with soft breaking terms arising at the Planck scale, it is generally possible to link flavor changing neutral current and CP violating processes occurring in the leptonic and hadronic sectors. We study the correlation between flavor changing squark and slepton mass insertions in models à la SU(5). We show that the constraints coming from lepton flavor violation exhibit a strong impact on CP-violating B decays.

Nonlocal symmetry breaking in Kaluza-Klein theories.

Scherk-Schwarz gauge symmetry breaking of a D-dimensional field theory model compactified on a circle is analyzed. It is explicitly shown that forbidden couplings in the unbroken theory appear in the one-loop effective action only in a nonlocal way, implying that they are finite at all orders in perturbation theory. This result can be understood as a consequence of the local gauge symmetry, but it holds true also in the global limit.

CP Violation and Flavor Changing Effects in K and B Mesons from Nonuniversal Soft Breaking Terms.

We analyze CP violation and flavor changing effects in a minimal supersymmetric standard model with arbitrary nonuniversal soft breaking. Large flavor changing neutral current effects are naturally expected in the K system, even in the absence of quark-squark flavor misalignment. However, the B system is sensitive to new supersymmetric contributions only if nonuniversality implies, not only different soft terms for the three generations but also a large quark-squark misalignment. The only exceptions are processes with a leading chirality changing contribution proportional to tanbeta (as b-->sgamma).

A simple, low-cost and fast Peltier thermoregulation set-up for electrophysiology.

Most of the parameters recorded in electrophysiology are strongly temperature dependent. In order to control temperature fluctuations we have built a system that ensures an accurate thermoregulation of the recording chamber. Temperature of physiological preparations can be changed relatively quickly (about 8 degrees C/min) and with a good accuracy (+/- 0.5 degrees C) without inducing thermal oscillations. Contrary to other thermoregulating devices, the temperature regulation is not carried out through the perfused medium but directly at the bottom of the chamber where a 3-cm2 Peltier element has been placed. The element is driven by a dedicated electronic device which controls the amount and the direction of the current flowing across the Peltier thermocouple. All construction details and the appropriate electrical circuits are provided. Using this home-made device, the steady-state chamber temperature could be precisely monitored with a resolution of +/- 0.1 degrees C in a range of 0-40 degrees C. This set-up was tested in experiments designed to evaluate the temperature dependence of synaptic transmission in the Torpedo nerve electroplate synapses and of calcium currents recorded from isolated nerve cells. This low-cost method is suitable for a wide range of applications.

[Major ambulatory surgery: organizational models]. / La chirurgia ambulatoriale maggiore: modelli organizzativi.

In this essay, the authors provide a definition for those medical care facilities representing a consolidated alternative to traditional hospitalization. These facilities can be basically ascribed to the following patterns: day case surgery; day-hospital activity; home-care. Day case surgery is a complex and, in most cases, interdisciplinary procedure; this type of activity necessitates a pre-hospitalization period and often also a "protected discharge" or even a home-care service. Some specific criteria regarding day surgery activity have been defined as follows: the main criteria have a clinical nature, but they interact with others belonging to a social and structural-organizational order. The Royal College of Surgeons of United Kingdom has officially recognized in 1985 this medical care typology as one of the constituents of surgical care, and has evaluated that at least 1/3 of the overall operations could be carried out as day care surgery. In the United States, besides hospital and ambulatory surgery activity, a new pattern known as "free-standing center" has been promoted; in 1993, 35% of the operations is expected to be carried out in day case surgery centers. As far as Italy is concerned, in 1988 only day-hospital practice has been adequately recognized as an alternative medical care facility to traditional hospitalization. The Emilia Romagna region, in order to increase day case surgery activity, has issued in 1991 a list of 53 DRGs, in which day bed units treatment was possible. Up to now, however, only a small part of these diseases is treated on a day case surgery basis.