Biomedical subjects

Pietro Impellizzeri

Publications and source records attributed to Pietro Impellizzeri.

5 recordsLinked to original sources

PubMed2006

Scintigraphic evaluation of colonic motility in patients with anorectal malformations and constipation.

BACKGROUND AND PURPOSE: Constipation is one of the major sequelae in patients after correction of anorectal anomalies (ARAs). The aim of the present work has been to assess the colonic transit time, using radioisotope scintigraphy, in patients operated for ARA and experiencing constipation in the follow-up. The results were compared with transit time from children with true functional constipation. METHODS: Twelve or 32 patients operated for ARA during the period 1994-2003 experienced mild or severe constipation (6 with high or intermediate form of ARA and 6 with low type) at follow-up. The mean age of this group was 5.8 years. Eighteen patients, mean age 6.7 years, with true functional constipation were studied as well. Colonic transit times were investigated using radioisotope scintigraphy. Normal values for colonic transit time were derived from historical controls. Radioisotope diethylenetriamine pentaacetic acid labelled with indium 111 was administered orally to determine a segmental colonic transit. Images of the abdomen have been taken at 6, 24, 48, and again at 72 hours, if radioactivity was not cleared from the colon. To quantify colonic transit, we calculated the geometric centre (GC) dividing the colon into anatomic regions. RESULTS: According to normal controls, 2 different type of delayed transit can be observed: (a) slow-transit constipation if GC at 48 hours is less than 4.1; (b) functional rectosigmoid obstruction (FRSO) if GC at 48 hours is 4.1 or more but less than 6.1 at 72 hours. Patients with functional constipation were divided into 2 groups: (a) slow-transit constipation in 12 patients with a GC at 48 hours of 3.7 +/- 0.5; (b) FRSO in 6 patients with a GC of 4.7 +/- 0.04 and 5.02 at 48 and 72 hours, respectively. Patients operated for high ARA had values characteristic of FRSO with GC at 48 hours of 5.1 +/- 0.8 and 4.75 +/- 0.5 at 72 hours. In low ARA, the transit times were similar to the ones observed in patients with high ARA at 48 hours with a GC of 4.9 +/- 0.5. CONCLUSIONS: Patients with ARA frequently have functional sequelae in the postoperative period such as constipation. According to our results, constipation seems to be secondary to segmental motility disorders limited to the rectosigmoid area, similar to constipated children with FRSO. No evidence of more generalised motility disturbance, as previously postulated, could be recorded.

Abnormalities, Multiple↗

PubMed2004

Raxofelast, a hydrophilic vitamin E-like antioxidant, reduces testicular ischemia-reperfusion injury.

Testis torsion is a surgical emergency that lead to permanent gonad damage. The damage has been ascribed to mechanisms of ischemia-reperfusion similar to other tissues. The mechanisms involved are different, but the lipid peroxidation of plasma membrane, caused by reactive oxygen species (ROS), generated particularly during reperfusion, is one of the most accredited. In the present study, we aimed to evaluate the effects of raxofelast, a vitamin E-like antioxidant with potent action and no systemic toxicity, on lipid peroxidation and histopathology in both testes after unilateral testicular torsion and detorsion. Adult male Wistar rats were subjected to total occlusion (3 h) of the left testis followed by 4 hours of reperfusion (TI/R). Sham testicular ischemia-reperfusion rats (SHAM TI/R) were used as controls. The animals were then randomized to receive either vehicle (1 ml/kg/i.p. of a dimetylsulphoxide/NaCl 0.9% 1:10 v/v solution, injected either 15 min before detorsion and 15 min after detorsion) or raxofelast (20 mg/kg i.p. 15 min before detorsion and 15 min after detorsion). Conjugated dienes (CD) levels, an index of lipid peroxidation, and testis histopathology were evaluated. Testicular ischemia reperfusion (TI/R) in untreated rats produced high testicular levels of CD (3.6+/-0.3 DeltaABS/g protein on the left side and 2.5+/-0.2 DeltaABS/g protein on the right side). Furthermore, histological examination revealed marked damage to the testis interstitium with severe haemorrhage and edema. The administration of raxofelast lowered CD levels (2.8+/-0.2 DeltaABS/g protein on the left side and 1.9+/-0.1 DeltaABS/g protein in the right side) and significantly reduced histological damage. These data suggest that the hydrophilic vitamin E-like antioxidants are good candidates for designing a novel therapeutic strategy to halt the oxidative stress that follows acute testis torsion.

Animals↗

PubMed2004

Immunohistology of aquaporin-1 and stem cell factor-receptor in human undescended testes.

OBJECTIVES: Both aquaporin (AQP) 1 and the stem-cell factor/C-kit system seem to have a definite role in testis function, but very few studies have been reported in humans, especially in the paediatric age group. With the present study we wanted to investigate the expression of these proteins to better delineate their role in normal and pathologic testes. METHODS: Immunohistology using AQP 1 and C-kit antibodies was performed on paraffin sections of open-testicular biopsies from 32 undescended testes. The testes of cryptorchid patients, with ages ranging from 2 to 15 years, were biopsied during an orchidopexy operation, after obtaining informed consent. Control biopsies, from 8 patients of matched age, were obtained during operations for inguinal hernia or hydrocele, always after obtaining informed consent. Positive results were recorded as diffuse or focal patterns and scored as weak, moderate or strong immunostaining. RESULTS: AQP 1 antibody strongly depicted microvessel endothelial cells, but was unlabeled in endotubular and interstitial cell lines, in both control and undescended testes. The C-kit immunostaining in normal testes revealed a diffuse, strong staining in the cytoplasm of spermatogonia and primary spermatocytes. However, in the undescended testes a focal C-kit immunolabelling was weakly recognized in both spermatogonial and immature Sertoli cells. CONCLUSIONS: These results indicate a direct involvement of AQP 1 in the regulation of fluid transport across the endothelial cell membranes of testicular microvessels. A role of the C-kit receptor protein is also substantiated by its strong expression in the maturing spermatogonia of the normal testes, but was minimally or not recognizable in undescended prepubertal testes.

Adolescent↗

PubMed2003

Peritoneal macrophage activity after laparoscopy or laparotomy.

BACKGROUND/PURPOSE: The beneficial effect of laparoscopy on the immune system seems not to be present at the peritoneal level at which the local immunity appears to be impaired by CO2. The aim of this study was to investigate the peritoneal macrophages (MPhis) activity after laparoscopy and laparotomy. METHODS: Thirty rats (300 to 350 g) were used and divided into 3 groups. In the laparotomy group, the peritoneum was opened and the abdominal wall exposed to air for 60'. In the laparoscopy group, pneumoperitoneum was created and maintained at 4 to 6 mm Hg for 60'. In the control group, anaesthesia was maintained for 60' without any other manipulations. Twenty-four hours after operation, peritoneal MPhis were harvested and cultured. The authors investigated nitrite/nitrate (NOx) production as well as the message for the inducible nitric oxide (iNOS), with the reverse transcriptase polymerase chain reaction under basal condition and after Lipopolysaccharide (LPS) stimulation. RESULTS: Basal MPhi NOx release was significantly higher after laparoscopy than either after laparotomy or control. LPS stimulation produced a strong increase in NOx production in laparotomy MPhis and control MPhis. In contrast, the increase in NOx production was markedly reduced in MPhi harvested after laparoscopy. Similar results were obtained for macrophage mRNA for iNOS; indeed, the increase in iNOS mRNA after LPS stimulation was blunted severely in MPhi from laparoscopy group. CONCLUSIONS: MPhis after laparoscopy display an higher basal immune performance. After a second insult (LPS), they display a state of tolerance or desensitisation (blunted NOx production and reduced mRNA expression). This observation could have important implications in considering laparoscopy in patients with malignancy or sepsis.

Animals↗

PubMedDate not supplied

[Prenatal diagnosis of pelvic floor malformations].

Pelvic floor malformations are congenital defects in the pelvic and perineal area, which are derived from a defective development of the cloaca membrane, the uro-rectal septum, the mesonephric and para-mesonephric ducts and the urogenital sinus. These are complex anomalies with a profound emotional impact on parents. The prenatal diagnosis is possible favoring the prenatal counseling for the parents and expediting the post-natal evaluation and management. Aim of the present paper is to review the current criteria for the prenatal diagnosis of the following malformations: anorectal anomalies, cloacal anomalies, persistence of the urogenital sinus, bladder and cloacal exstrophy and ambiguous genitalia.

Anal Canal↗