PubMed Health⌕ Search

Biomedical subjects

A Santarelli

Publications and source records attributed to A Santarelli.

11 recordsLinked to original sources
PubMed2006

Effectiveness of a new decisional algorithm in managing mandibular ameloblastomas: a 10-years experience.

We present a new treatment algorithm aimed to assist surgeons to develop a rational diagnostic protocol and establish effective conservative surgical management in patients with mandibular ameloblastoma. Fifteen consecutive cases treated by conservative management were reviewed. Data collected included age, sex, symptoms and signs at diagnosis, anatomical distribution of the lesions, numbers and types of operations, number of recurrences, and duration of follow-up post-operatively. Curettage was the first operation for all patients and they were closely followed-up post-operatively. During the follow-up period (4-10 years), small recurrences were diagnosed early in 7 patients who were treated by radical surgery including marginal or "box" resection. No further recurrences were observed after the second operation. When detected early, recurrences are small and surrounded by a large amount of uninvolved normal bone so it is possible to manage them with a radical resection, so lowering the risk of further recurrence and avoiding severe cosmetic and functional problems.

Adolescent↗
PubMed2005

p63 expression in odontogenic cysts.

A total of 123 cases of odontogenic cysts, distributed as follows: 30 follicular (FC), 35 radicular (RC), 53 keratocysts, 1 glandular odontogenic and 4 calcifying odontogenic cysts, were analysed by immunohistochemistry for expression of p63, a component of p53 protein family. In RCs p63 positivity was not only in basal and parabasal layers but also in the intermediate layer and about 1/3 of cases displayed a percentage of stained cells comprised between 0 and <5%, and about 2/3 between >5% and <50%. In FCs positivity was confined to basal and parabasal layers of the epithelium and in the majority of FCs the stained cells were comprised between 0 and <5%. OKCs displayed the most intense and diffuse p63 labeling. In conclusion, these data suggest that p63 expression may be useful to identify cysts type with more aggressive and invasive phenotype supporting the hypothesis of a suprabasal proliferative compartment in OKCs.

DNA-Binding Proteins↗
PubMed1997

Paroxysmal atrial fibrillation in sleep.

Thirty-eight patients with lone paroxysmal atrial fibrillation (PAF) were monitored during spontaneous sleep. The starts of 111 episodes of atrial fibrillation (AF) occurred in 12 patients. Statistical analysis failed to disclose significant differences in the number of starts per hour between wakefulness and the different sleep stages. Heart rate (HR) in the 60 seconds prior to a PAF episode did not show significant changes with respect to fragments of recording taken away from PAF episodes. As expected, spectral analysis of HR variability during sleep (basal values) showed a reduction of low frequency/high frequency (LF/HF) ratio during slow sleep, while the ratio returned to values similar to wake levels during REM sleep. In the 2 minutes preceding a PAF episode the LF/HF ratio of the spectral power was more unstable with a clear-cut prevalence of sympathetic activity both in wake and in different sleep stages. A shift toward parasympathetic activation was never seen before the start of any of the 17 PAF episodes recorded during sleep.

Adult↗
PubMed1993

Flecainide acetate: concentration-response relationships for antiarrhythmic and electrocardiographic effects.

In order to evaluate the concentration-response relationship for either antiarrhythmic or electrocardiographic effects, 13 patients with symptomatic, stable, premature ventricular contractions (> 100/hour) were selected, and flecainide was administered as a single oral dose (200 mg) and as chronic treatment (150 mg b.i.d. for 21 days). In both settings a Holter monitoring, serial electrocardiogram (ECG) tracings and serum samples for flecainide concentrations were obtained; the relationships between drug levels, antiarrhythmic efficacy, and ECG modifications were analysed. The results obtained indicated that QRS and PR intervals lengthened significantly either after acute oral administration or after chronic treatment by 21-36% (mean values), and that the QRS interval changes were significantly correlated to serum flecainide concentrations (r = 0.68, p < 0.001 after acute and r = 0.79, p < 0.001 after chronic administration). However, for any given plasma concentration of flecainide, the percentage widening of QRS intervals was smaller after chronic treatment, as shown by the different slopes of the correlation lines (7.7 +/- 4.0% ml.micrograms -1 after acute dosing versus 3.8 +/- 1.1% ml.micrograms -1 after chronic treatment, p < 0.001). This finding suggests a relative reduction of flecainide's effects on ECG intervals during chronic treatment, while the antiarrhythmic efficacy was maintained (flecainide effective in 8/13 patients in acute and in 11/13 patients in chronic) without significant differences between flecainide's minimal effective concentrations (262 +/- 119 ng/ml and 319 +/- 276 ng/ml for acute vs chronic respectively). We conclude that during chronic treatment a dissociation seems to occur between the electrocardiographic and the antiarrhythmic effects and this could limit the clinical usefulness of monitoring QRS intervals.

Administration, Oral↗
PubMed1993

[Paroxysmal atrial fibrillation: the significance of the dynamic behavior of the atrial cycle].

The aim of this study was to evaluate the dynamic atrial endocardial activation pattern during atrial fibrillation and to investigate the electrophysiologic changes related to the self-termination of the arrhythmia. Twenty patients with daily recurrences of lone paroxysmal atrial fibrillation episodes underwent electrophysiological study with contemporary recording of the atrial signal in high right atrium, low right atrium and coronary sinus. Sixty episodes lasting longer than 1 min were recorded, 22 spontaneous and 38 induced with a single extrastimulus. A significant correlation has been demonstrated for the mean of 100 consecutive intervals evaluated at the arrhythmia onset and the atrial functional refractory period (R = 0.73, p < 0.001). Mean FF length increased significantly in the minute preceding self-termination of atrial fibrillation in all the 3 recording sites. On the contrary, a significant decrease of mean FF length was documented in long lasting episodes. Self-termination of atrial fibrillation episodes implies a peculiar pattern of intra-atrial interval. Therefore the analysis of FF intervals seems to have pathophysiological implication and may be applied also to evaluate pharmacological interventions.

Adolescent↗
PubMed1992

Atrial premature beats coupling interval determines lone paroxysmal atrial fibrillation onset.

In 20 patients with recurrent episodes of lone paroxysmal atrial fibrillation we assessed the onset pattern of each episode of either atrial fibrillation or of atrial flutter during a 24-h Holter monitoring. We evaluated 24 twenty-four-hour Holter tape recordings and our data are related to 168 episodes of paroxysmal atrial fibrillation and 27 episodes of paroxysmal atrial flutter. Eighty-five percent of atrial fibrillations and 67% of atrial flutters were of short duration (less than 5 min). The majority of patients (80%) had either nocturnal or daily episodes of arrhythmia and PP intervals immediately before onset of arrhythmia did not show significant variations in 77% of cases. The coupling interval of the supraventricular premature beats eliciting atrial fibrillation was significantly shorter than the coupling intervals of the spontaneous isolated supraventricular premature beats (p less than 0.0001); again, in 6 patients with either atrial fibrillation or flutter, the coupling interval at onset of fibrillation was significantly shorter in comparison to flutter (p less than 0.0001). In conclusion, vagal or sympathetic prevalence does not seem to influence significantly the beginning of the arrhythmia, while the coupling interval of the atrial premature beats plays a critical role in the inducibility of atrial flutter or fibrillation.

Adult↗
PubMed1992

Evaluation by cardiopulmonary exercise test of DDDR versus DDD pacing.

UNLABELLED: In eight patients (age 62 +/- 6 years) a DDDR pacemaker was implanted for sick sinus syndrome (three cases) or second- and third-degree AV block (five cases). In five subjects chronotropic incompetence (maximal heart rate on effort < 110 beats/min) was present before implantation. One month after implantation the patients were randomized to DDDR or DDD pacing for 3 weeks each, with subsequent crossover, and at the end of each period a symptom limited cardiopulmonary exercise test (25 watts/2 min) was performed and the patients were requested to fill a symptoms questionnaire. RESULTS: DDDR pacing, compared to DDD, was associated with higher maximal heart rates (127 +/- 20 vs 110 +/- 27 beats/min, P < 0.02), higher [VO2 max (25.4 +/- 6.1 vs 21.5 +/- 7.8 mL/kg/per min, P < 0.03) and higher VO2 at the anaerobic threshold (20.3 +/- 5.0 vs 15.8 +/- 4.9 mL/kg per min, P < 0.03), without significant differences in mean exercise time (526 +/- 193 vs 472 +/- 216 sec, NS). The increase in VO2 max obtained in DDDR versus DDD was significantly related to the increase in maximal heart rate (r = 0.72, P < 0.05) and the increase in VO2 at the anaerobic threshold obtained in DDDR versus DDD was related to the increase in heart rate at the anaerobic threshold (r = 0.81, P < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Anaerobic Threshold↗
PubMed1988

Dextran-coated silica packings for high-performance size-exclusion chromatography of proteins.

Porous silica beads have excellent mechanical properties for the high-performance liquid chromatography of proteins. However, the importance of non-specific interactions between silanols on the silica surface and the proteins requires a modification of these supports before they can be used as stationary phases for size-exclusion chromatography (SEC). Silica beads were coated with dextran bearing a small number of positive charges in order to neutralize the negatively charged silanol groups. Diethylaminoethyl-dextrans (DEAE-dextrans) with a relatively low percentage of dextran units bearing DEAE functions were layered on the silica beads. The influence of several characteristics of these packings on chromatographic performance were studied in order to determine the optimal conditions for the SEC of proteins.

Chromatography, DEAE-Cellulose↗
PubMedDate not supplied

Genetic analysis of oral squamous cell carcinoma by cDNA microarrays focused apoptotic pathway.

We investigated mRNA expression of the genes involved in the apoptotic mechanism in oral squamous cell carcinoma (OSCC) by cDNA microarray. The aim of this study was to identify genes mainly involved in tumorigenesis, comparing the difference of gene expression in neoplastic and non-neoplastic tissues. Eight frozen samples of OSCC and the corresponding normal oral mucosa were treated to obtain mRNA. The mRNA extracted from these specimens was converted into cDNA and analyzed with SuperArray GEArray Q Series Human Apoptosis Gene Array kit. Our results showed that in OSCC there is a different expression of CRADD, FADD, ATM and APAF-1 genes compared to normal mucosa. Real-Time PCR, and Western blot analysis were performed on a separate cohort of patients in order to confirm the results obtained by DNA microarray. Our analysis of apoptotic process through microarray technology confirmed that different molecules could be responsible or favour the imbalance of apoptosis in cancer tissues. Microarray technology has made it possible to analyze the expression of multiple genes in a single experiment. However, most commercial array kits, designed to include as many genes as possible, produce a vast amount of data that often is difficult to interpret. In addition, the cost of equipment is often prohibitive. In contrast, the focused kit used was a complete, affordable and effective method to improve knowledge of molecular specific pathways.

Apoptosis↗
PubMedDate not supplied

Raloxifene covalently bonded to titanium implants by interfacing with (3-aminopropyl)-triethoxysilane affects osteoblast-like cell gene expression.

Since Raloxifene, a drug used in osteoporosis therapy, inhibits the osteoclast functions but not osteoblast functions, it could improve the recovery during implant surgery. This preliminary report describes a simple method to link, through a covalent bond, Raloxifene to titanium by interfacing with (3-aminopropyl)-Triethoxysilane as assessed by the IR-FT and SEM. To evaluate the biological response of osteoblast-like cells to this implant, we compared expression gene profiling of cell cultures on Raloxifene conjugated implant and normal implant by DNA microarray. By using DNA microarrays containing 19,200 genes, we identified differently expressed genes in osteoblast-like cell line (MG-63). Surface Raloxifene conjugated implants have been shown to have a relevant importance in modifying cell response. This result could be an interesting starting point for the use of an immediate functional loading of implants.

Cell Line↗