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Riassunto Obiettivi Obiettivo del presente lavoro e quello di confrontare uno studio diagnostico-cefalometrico effettuato su teleradiografia tradizionale con quello realizzato su radiogrammi ottenuti con TC 3D. Vengono inoltre valutati vantaggi e svantaggi offerti dalle due differenti metodiche tomografiche 3D. Materiali e metodi Due pazienti adulti sono stati sottoposti a esame radiografico con metodica tradizionale e con l’impiego di due differenti TC 3D, una utilizzante una tecnologia Fan Beam, l’altra Cone Beam. I cefalogrammi cosi ottenuti sono stati studiati sia attraverso un’analisi cefalometrica digitale tradizionale, sia impiegando un software di cefalometria 3D. Risultati e Conclusioni La Tomografia Computerizzata fornisce un’informazione piu accurata della radiografia tradizionale perche priva di deformazioni, ingrandimenti, sovrapposizioni e artefatti e risulta oggi fondamentale nello studio delle disgnazie dento-maxillo-facciali nelle tre dimensioni dello spazio. In particolare la tecnologia Cone Beam utilizza una bassa dose di radiazioni e rende l’esame piu economico per pazienti e strutture mediche. L’utilizzo di un programma di cefalometria 3D, offre la possibilita di sfruttare a pieno le informazioni tridimensionali ottenute con la TC ed e particolarmente indicato nello studio di pazienti con asimmetrie facciali, poiche consente di studiare i due lati separatamente e di confrontarli fra loro.

Testosterone regulates energy metabolism and skeletal muscle mass in males, but the molecular mechanisms are not fully understood. This study investigated the response of skeletal muscle to castration and testosterone replacement in 8-week-old male mice. Using microarray analyses of mRNA levels in gastrocnemius muscle, 91 genes were found to be negatively regulated by testosterone and 68 genes were positively regulated. The mRNA levels of the insulin signalling suppressor molecule Grb10 and the glycogen synthesis inhibitors, protein phosphatase inhibitor-1 and phosphorylase kinase-γ, were negatively regulated by testosterone. The insulin-sensitive glucose and amino acid transporters, Glut3 and SAT2, the lipodystrophy gene, Lpin1 and protein targeting to glycogen were positively regulated. These changes would be expected to increase nutrient availability and sensing within skeletal muscle, increase metabolic rate and carbohydrate utilization and promote glycogen accumulation. The observed positive regulation of atrogin-1 (Fbxo32) by testosterone could be explained by the phosphorylation of Akt and Foxo3a, as determined by Western blotting. Testosterone prevented the castration-induced increase in interleukin-1α, the decrease in interferon-γ and the atrophy of the levator ani muscle, which were all correlated with testosterone-regulated gene expression. These findings identify specific mechanisms by which testosterone may regulate skeletal muscle glucose and protein metabolism.

At present, laparoscopy is used mainly as a diagnostic tool in patients with abdominal stab wounds.Thirty-two hemodynamically stable patients with isolated stab wounds of the anterior abdomen, thought to be penetrating, were prospectively selected to undergo treatment via a laparoscopic approach. When possible, parenchymal wounds were coagulated or sealed, and wounds to the intestines were sutured or stapled.The results of laparoscopy were negative in 6 (18.8%) of the cases: nonpenetrating wounds in 4 cases and nonsignificant organ injury in 2 cases. A hemoperitoneum was identified in 13 (40.6%) of the cases, and significant organ injuries in 26 (81.3%) of the cases: stomach, 2; small bowel, 5; colon, 2; pancreas, 1; vascular injuries, 4; liver, 5; mesentery, 9. Laparoscopy was therapeutic in 20 (62.3%) of the cases. Conversion to open surgery was required in 6 (18.8%) of the cases. No injuries were missed, and no mortality occurred. Postoperative complications developed in 2 (6.2%) of the cases. The mean hospital stay was 4 days, with no late complications.Laparoscopy can avoid a number of unnecessary laparotomies and can treat most of the lesions found in hemodynamically stable patients with anterior abdominal stab wounds.

The aim of this study is to prove if dynamic HASTE (half-Fourier acquisition single-shot turbo spin-echo) sequences can be used in the diagnosis of internal derangement disorders of temporomandibular joint (TMJ) as an alternative to static proton density (PD) weighted/turbo spin echo (TSE) T2-weighted sequences which are considered up to now as the gold standard in the evaluation of TMJ disorders (TMDs).194 patients for a total of 388 TMJs were examined with a 1.5 Tesla field strength superconducting magnet. Sagittal static PD-weighted/TSE T2-weighted and dynamic HASTE sequences have been used. Three experts in the field of oral radiology (specialist A, B and C) independently and blinded to clinical symptoms and any treatment, assessed the articular disc position in each TMJ (rated as normal or disc displacement with reduction or disc displacement without reduction). The agreement between static and dynamic images and between the three different specialists in the assessment of the articular disc position was evaluated using kappa statistic.The agreement between static and dynamic images is: for specialist A, K = 0.862; for specialist B, K = 0.870 and for specialist C, K = 0.862.Since there is no complete agreement between these two MR techniques, dynamic sequences can not be used as a reliable alternative to static sequences in the evaluation of internal derangement disorders of TMJ.

Several measurements on a variety of semiconductor photocathodes were performed in order to determine their photoelectric quantum efficiency. Two different excimer lasers (XeCl and KrCl) and a pulsed Xe lamp were used as light sources for electron photoextraction from doped and undoped samples of cadmiun telluride, indium antimonide, and indium phosphide. Large current densities were obtained up to the limit of the Child–Langmuir law. This suggests the use of these materials for the production of intense electron sources, which could also be used for purity measurements of noble liquids.

Cholecystectomy is associated with increased risk in patients with liver cirrhosis. Moreover, cirrhosis and portal hypertension have been considered relative or absolute contraindication to laparoscopic cholecystectomy. As experience with laparoscopic cholecystectomy increased, we decided to treat cirrhotic patients via this approach. Between January 1994 and April 1995, nine patients with a Child-Pugh's stage A cirrhosis underwent elective laparoscopic cholecystectomy with intraoperative cholangiography. There was no significant per- or post-operative bleeding and no blood transfusion was necessary. There was no mortality and very low morbidity. Median hospital stay was 3 days. This series suggests that wellcompensated cirrhosis can not be considered a contraindication to laparoscopic cholecystectomy.

The hepatitis C virus is a common cause of chronic hepatitis after orthotopic liver transplantation (OLT). We evaluated 95 consecutive patients who underwent OLT at our institute between March 1988 and November 1992 and who had a follow-up period longer than 3 months. All patients had a second-generation test (ELISA + RIBA) for HCV antibodies (HCV Ab) before and monthly after OLT; all had a polymerase chain reaction (PCR) test for detection of viral RNA after the operation. Whenever biochemical abnormalities (hyper-transaminasemia 2 times the normal range) were seen, a percutaneous liver biopsy was performed. Forty-two HCV Ab + patients before OLT remained positive after OLT. In this group the PCR test was positive in 32 cases (78.5%). In 13/42 (30.9%) cases (all PCR +) with hypertransaminasemia histological examination showed signs of viral C hepatitis (score of Knodell minimum 3, maximum 12, median 5.5). Of 53 HCV Ab patients before OLT, only 1 became HCV Ab+ and PCR+ 15 months after OLT. In the remaining 52 patients 15 were PCR+. Twenty of 53 patients (37.7%) had a liver biopsy because of hypertransaminasemia: in no case did histology show any signs of hepatitis C. In conclusion, viral C recurs often after OLT for post-hepatitic C cirrhosis. The histological graft lesions are in most cases moderate. We did not observe any deaths related to viral C infection in grafted patients. According to our results post-hepatic C cirrhosis remains a good indication for OLT.

A software program for use in the investigation of specialized springs used in the segmented arch technique has previously been developed and an example of its clinical application has been shown. The purpose of this study was to further assess the reliability of the software in 4 tests using T-loop springs. A numerical simulation of a determined experimental condition relative to a T-loop spring was carried out in each test. Numerical and experimental results were compared, and the precision of the analytical tool was assessed relative to a variety of parameters of the spring. Since the comparison between numerical and experimental results showed good agreement along the entire range of activation of the spring, the reliability of the software is sufficient for the clinical purposes of the segmented arch technique.

Some 5-10 per cent of patients with congenital 'solitary' liver cysts develop symptoms (pain, gastric outlet obstruction or jaundice), and require treatment.Ten consecutive patients with symptomatic non-parasitic liver cysts have been treated by laparoscopic fenestration.There were no postoperative complications. During a median follow-up of 25.5 months with ultrasonographic examination there has been no recurrence of the cysts and the patients remain asymptomatic.The minimal access surgical approach by laparoscopic fenestration could become standard treatment for simple liver cysts.