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M Liberti

Publications and source records attributed to M Liberti.

At least 19 recordsLinked to original sources
PubMed2006

Comparison between low-level 50 Hz and 900 MHz electromagnetic stimulation on single channel ionic currents and on firing frequency in dorsal root ganglion isolated neurons.

Alteration of membrane surface charges represents one of the most interesting effects of the electromagnetic exposure on biological structures. Some evidence exists in the case of extremely low frequency whereas the same effect in the radiofrequency range has not been detected. Changes in transmembrane voltages are probably responsible for the mobilization of intracellular calcium described in some previous studies but not confirmed in others. These controversial results may be due to the cell type under examination and/or to the permeability properties of the membranes. According to such a hypothesis, calcium oscillations would be a secondary effect due to the induced change in the membrane voltage and thus dependent on the characteristics of ionic channels present in a particular preparation. Calcium increases could suggest more than one mechanism to explain the biological effects of exposure due to the fact that all the cellular pathways using calcium ions as a second messenger could be, in theory, disturbed by the electromagnetic field exposure. In the present work, we investigate the early phase of the signal transmission in the peripheral nervous system. We present evidence that the firing rate of rat sensory neurons can be modified by 50/60 Hz magnetic field but not by low level 900 MHz fields. The action of the 50/60 Hz magnetic field is biphasic. At first, the number of action potentials increases in time. Following this early phase, the firing rate decreases more rapidly than in control conditions. The explanation can be found at the single-channel level. Dynamic action current recordings in dorsal root ganglion neurons acutely exposed to the electromagnetic field show increased functionality of calcium channels. In parallel, a calcium-activated potassium channel is able to increase its mean open time.

Action Potentials↗
PubMed2005

Use of local hyperthermia as prophylaxis of fibrosis and modification in penile length following radical retropubic prostatectomy.

OBJECTIVE: The aim of the study was to evaluate the effectiveness of local hyperthermia in reducing possible penile shortening following radical retropubic prostatectomy. PATIENTS AND METHODS: The study population comprised 40 patients, aged 52-74 years, submitted to radical retropubic prostatectomy. Patients were divided into two groups of 20. In Group A, patients were submitted to local hyperthermia 3 weeks after surgery, three times a week, with treatment lasting 30 min. Patients received a total of 10 applications, which reached a local temperature of 39-40 degrees C. A second cycle was repeated after 1 month. In Group B, patients were submitted only to post-operative follow-up once a month. Penile length was measured in all patients both before and 3 months after surgery in the 'stretching phase' from the pubo-penile junction to the tip of the glans. RESULTS: In Group A patients (hyperthermia treatment), no variation in penile length was observed in 16 cases (80%), while the reduction ranged from 0.5-1.5 cm in four cases (20%). In Group B, 12 patients (60%) showed a reduction in penile length ranging from 0.5-2.5 cm, while penile length remained unchanged in eight patients (40%). CONCLUSIONS: Results of this study demonstrate a mild but statistically relevant reduction in penile shortening following low-grade, externally delivered penile hyperthermia, thus confirming the efficacy of this approach in preventing penile shortening caused by post-ischaemic fibrosis.

Aged↗
PubMed2005

Role of hyperthermia in the treatment of Peyronie's disease: a preliminary study.

OBJECTIVE: Previous experience in the treatment of plaque with hyperthermia in orthopaedics led the authors to investigate the effectiveness of this approach in patients with Peyronie's disease. PATIENTS AND METHODS: The study population comprised 60 patients (aged 36-76 years) with advanced Peyronie's disease. Patients were divided into two groups (A and B), with 30 in each. Group A patients underwent local hyperthermia treatment, with 30-min treatment sessions twice a week for 5 weeks. Patients received a total of 10 applications, which reached a local temperature of 39-40 degrees C. A second cycle was repeated after a 1-month interval for a total of 20 treatment sessions. Group B patients were treated with intra-plaque infiltrations using 10 mg verapamil; they received one infiltration once a week for 3 months. Differences between the two groups, as well as between variables (before and after treatment), were analysed using Student t-test and Fisher test. RESULTS: Hyperthermia significantly reduced plaque size and penile curvature and led to an increase in mean scores of erectile function (EF) domain, while verapamil had no such effects. Haemodynamic parameters were not significantly modified in either group. Hyperthermia caused significantly fewer side effects than verapamil infiltrations and was significantly more effective in preventing disease progression. There were no significant differences between the two groups in terms of pain reduction during erection. CONCLUSIONS: Results of this study stress the efficacy of hyperthermia in the treatment of advanced Peyronie's disease.

Adult↗
PubMed2001

Role of 5-aminolevulinic acid in the diagnosis and treatment of superficial bladder cancer: improvement in diagnostic sensitivity.

OBJECTIVES: To use 5-aminolevulinic acid (5-ALA) in diagnostic cystoscopy and during transurethral resection of the bladder (TURB) to treat transitional cell carcinoma. The efficacy of this new technique was compared with standard cystoscopy. METHODS: The 5-ALA, instilled in the bladder 2 hours before cystoscopy, makes the pathologic tissue fluorescent when illuminated with blue light (375 to 400 nm). This allows a better recognition of the neoplastic forms for both diagnostic and therapeutic purposes during TURB. This method has been used since May 1997 on 49 patients in whom bladder tumor was diagnosed either immediately or during postchemotherapy follow-up. RESULTS: One hundred seventy-nine biopsies were taken of fluorescent and nonfluorescent areas (3.5 per patient) to check the effectiveness of the new method compared with standard cystoscopy. A good correlation was found between 5-ALA cystoscopy and the histopathologic diagnosis, with a good sensitivity (87%). The 5-ALA cystoscopy allowed the diagnosis of a tumor in 24 patients with negative standard cystoscopic findings. Furthermore, 5-ALA cystoscopy detected 7 cases of carcinoma in situ. Neither local nor systemic (because of endovesical instillation) side effects were noted. CONCLUSIONS: We believe that 5-ALA could be routinely used in the diagnosis of superficial bladder tumors, as it was shown to improve the diagnostic sensitivity for carcinoma in situ and to reduce the risk of recurrence related to missed cancerous lesions or incomplete TURB.

Adult↗
PubMed2001

Superficial bladder tumors in patients under 40 years of age: clinical, prognostic and cytogenetic aspects.

Bladder carcinoma with transitional cells is the most frequent neoplasia in the urinary system, but it is quite rare in patients under 40 years of age (0.4-2%). An analysis of 21 patients under 40 and a review of other reports show that tumors in patients under 20 years old have little tendency to recur and to progress, while tumors in patients aged between 21 and 40 have a behavior pattern similar to older age groups regarding recurrence and disease progression. Preliminary results of a study using fluorescent in situ hybridization with probes for the centromere of chromosomes 7 and 17 showed a high incidence of aneusomy with regard to these chromosomes and a genetic difference between superficial tumors in the young and in adults. Using probes from chromosomes already described in bladder carcinogenesis, we obtained higher sensitivity and specificity in detecting aneuploid events.

Adolescent↗
PubMed1997

[Radiologic staging after surgical, chemical, and radiation treatment of non-seminomatous tumors of the testis].

The aim of this work was to evaluate the clinic usefulness of Computed Tomography (CT) and Magnetic Resonance (RM) in the staging after surgery, radiotherapy and chemotherapy of the nonseminomatous germ cells tumours of the testis. The Authors discussed the CT and MR dimensional criteria for the diagnosis of retroperitoneal metastases of the nonseminomatous germ cells tumours and delineated their CT and MR morphologic appearances in detail. The density of the residual mass on CT was classified as solid, cystic and half-cystic. The retroperitoneal hematoma and lymphocele formed as a complication respectively of orchiectomy and retroperitoneal lymphadenectomy can be misinterpreted to represent metastatic disease on post operative staging CT scans. Early recognition of this complication are crucial if unnecessary treatment is to be avoided. Finally the Authors evaluated, in patients affected from nonseminomatous germ cells tumours of the testis, the possibility to characterize with CT and MR imaging the retroperitoneal mass. The density and character of the residual mass on CT scan did not reliably predict the histology. On the basis of tumor consistency and signal intensity in T1 and T2 weighted images, MR cannot yet warrant any conclusion about the ultimate effect of chemotherapy.

Germinoma↗
PubMed1989

[Surgical treatment of unrepairable vesicovaginal fistulas].

The authors discuss different types of urinary diversion as the therapy of unrepairable vesico-vaginal fistulas. They also describe the therapy performed in their experience and underline that, at the moment, rectal bladder is to be considered the best solution.

Colon↗
PubMed1986

[Behavior of certain forms of enzymuria in subjects treated with pipemidic acid].

Three groups of subjects (I with infections of the lower urinary ways; II with chronic pyelonephritis; III healthy controls) were treated with pipemidic acid for 10 consecutive days and the behaviour of their urinary NAG and AAP was studied. It was discovered that the healthy group and the patients with infections of the lower urinary ways showed no significant variations in the urinary activity of the two enzymes following the administration of pipemidic acid. However there was a distinct reduction in both enzymes in patients with chronic pyelonephritis who presented demonstrable bacterial sensitivity to the drug. Apart from the fact that it produces no nephrotoxic effects at least in the doses used and for the treatment period adopted, the drug is therefore considered to reduce renal inflammation that is beneficial to individuals with chronic interstitial nephropathy.

Acetylglucosaminidase↗
PubMed1985

[Partial and multiple correlations between 4 types of enzymuria in 2 groups of chronic nephropathic patients].

The urinary activity of four enzymes (NAG, GLU, GRS and GAL) was studied in two groups of patients suffering respectively from interstitial nephritis and chronic glomerulonephritis with the aim of further investigating enzyme variability through the theory of partial and multiple correlation. This study permitted the effects of two enzymes on the known correlations between the remaining two enzyme types to be studied. It was established that very stable relationships exist between each enzyme and the group composed of the remaining three. In particular, in patients with interstizial nephritis, correlations with GAL were all highly significant even if the effect of the other two enzymes was ignored. Similarly, correlations with GRS were strongly significant in patients with chronic glomerulonephritis. In the two groups studied, each enzyme appears to have a highly stable relationship with the other three. Accurate estimates may probably be achieved for GAL and GRS in both groups and for NAG in the glomerulonephritis sufferers. This is further evidence that the enzyme procedure may be used to differentiate between interstitial and glomerular nephritis.

Chronic Disease↗
PubMed1984

[Normal values of the urinary activity of 4 enzymes].

The urinary activity of 4 enzymes (NAG, GLU, GAL, GRS) was investigated in 105 healthy subjects in order to evaluate the variability of standard levels and establish the degree of such variations in relation to sex, age, weight and height. The results obtained demonstrate that these enzymurias do vary in relation to the parameters examined. Age and sex produced the most pronounced variations though height and body weight also appeared to have some influence. The study of variations in standard levels is of value in the interpretation of pathological enzymurias.

Acetylglucosaminidase↗
PubMed1984

[Stage P-1 primary neoplasia of the bladder. Critical evaluation of results obtained with the use of adriamycin and mitomycin C in the prevention of recurrences].

However adequately treated, surface carcinomas of the bladder recur sooner or later with infiltration found in about 10% of cases. Any development that may offer therapeutic progress and reduce the incidence of recurrences is therefore of primary importance. Two homogeneous groups of patients were selected for the present study: 35 were given Adriamycin and 25 Mitomycin C. In evaluating results, the incidence of recurrences in relation to the primary neoplasia and the existence of single or multiple tumors was analysed. It is concluded that Mitomycin C in association with either T.U.R. or T.V.R. is a particularly useful and indubitably effective form of topical chemotherapy in cases of single or multiple primary neoplasias.

Administration, Topical↗
PubMed1982

Ultrasound and computed tomography in staging of bladder tumours.

Eighty-seven patients with proven bladder tumours were retrospectively reviewed with ultrasound (US) and computed tomography (CT), in order to define the stage of the neoplasm. The tumours were divided into three groups with respect to the TNM classification system. Results indicate that US could predict an exact staging of the bladder tumours in 80.6% of cases in the first group (P1), 68.9% of cases in the second group (P2 - P3), and 90.0% of cases in the third group (P4). CT could predict an exact staging in 61.3% of the bladder tumours in the first group, 91.1% in the second group, and 90.0% in the third group. This finding suggests that the capability of US in detecting bladder tumours in stage P1 may avoid the use of CT, while in subsequent stages CT becomes valuable for the evaluation of extravesical invasions and lymph node metastasis.

Adult↗
PubMedDate not supplied

[Renal cholesteatoma].

Renal cholesteatoma is an extremely uncommon disease. The renal pelvis is the most common site, but the lesion can be localized, even if rarely, in a calix or in the ureter. Histologically it consists of a keratinizing desquamative squamous metaplasia, with absence of cellular atypia in the urothelium, therefore cholesteatoma is not considered as a premalignant lesion. Authors report a case of renal cholesteatoma and take into consideration particularly the question regarding the diagnostic approach, that in spite of the help of new imaging techniques, as TC, is unable to arrive at a certain diagnosis, and the therapeutic approach, that must be conservative, when it's possible and according to the majority of Authors.

Cholesteatoma↗
PubMedDate not supplied

[A case of epidermoid cyst of the testis].

The epidermoid cyst of the testis represents about 1% of all testicle tumours. The average age of presentation ranges from the second and the fourth decade of life. Its clinical features do not differ from those of a testis malignancy. Preliminary clinical and laboratory findings do not determine the diagnosis. The Authors report a case and review the Literature (about 150 cases up to 1985). Therapeutic strategy is also discussed: orchiectomy or simple removal of the cyst.

Adolescent↗