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V Jasonni

Publications and source records attributed to V Jasonni.

At least 55 records · Page 3Linked to original sources
PubMed1998

All mechanical low rectal anastomosis in children.

PURPOSE: The aim of this study is to demonstrate the feasibility and usefulness of mechanical suturing in children for low rectal anastomosis. METHODS: The study group includes 31 children operated on from January 1993 to July 1996 by the same senior surgeon, performing the modified Duhamel procedure for Hirschsprung's disease in 17 children, intestinal neuronal dysplasia in seven, and the Knight-Griffen procedure in seven pediatric patients with chronic ulcerative colitis. RESULTS: In all the cases the technique of "viscero-synthesis" was performed using the mechanical stapler. A circular stapler has been used for the end-to-end and the end-to-side anastomosis between the anal canal or the back wall of the rectum with the pulled viscus, while a linear endoscopic stapler (GIA) has been used for the consolidation of the rectocolic wall in the modified Duhamel technique. CONCLUSIONS: The results obtained demonstrate that the mechanical staplers in children are safe and effective in low rectal anastomosis, sparing operative time and reducing the risk of anastomotic dehiscence; however, the size of circular instruments limits its use in neonates and small infants.

Adolescent↗
PubMed1998

GDNF deficit in Hirschsprung's disease.

BACKGROUND/PURPOSE: In 1996, the glial cell line-derived neurotrophic factor (GDNF) was identified as one of the ligands of the RET transmembrane receptor. In the same year, GDNF mutations were found in association with RET protooncogene mutations in Hirschsprung patients. Mutations in GDNF per se are thought neither necessary nor sufficient to cause Hirschsprung's disease (HD). To date, our study group has identified GDNF mutations only in 2 of 98 cases of intestinal dysganglionosis. The aim of our study was to investigate a possible expression deficit of GDNF in the enteric nervous system of Hirschsprung patients not mutated for the GDNF gene. METHODS: We used rabbit polyclonal antibodies raised against a peptide corresponding to amino acids 186-205 mapping within the carboxy-terminal domain of human GDNF. GDNF expression was studied immunohistochemically in surgical specimens from 30 HD cases (27 classic forms and 3 ultralong forms) and from 10 age-matched controls. Serial sections from the same full-thickness specimens were investigated with the following histochemical and immunohistochemical techniques: acetylcholinesterase, lactate dehydrogenase, succinic dehydrogenase, alpha-naphthyl-esterase, glial fibrillary acid protein, S-100 protein, and neuron-specific enolase. RESULTS: A high level of GDNF expression was found in normal intestine and in Hirschsprung ganglionic segment. Satellite elements of myenteric ganglia presented a strong immunoreactivity to GDNF. Conversely, the aganglionic segment showed cholinergic hyperinnervation and hypertrophic trunks of nerve fibers in the muscular interstitium with complete absence of GDNF expression. The small ganglia of the hypoganglionic segment showed a reduced GDNF immunoreactivity. CONCLUSIONS: GDNF, a distantly related member of the transforming growth factor-beta superfamily, is a potent neurotrophic and survival factor for neurons and enteric ganglion cells. Mutations of the GDNF gene or GDNF expression deficit interrupt the faithful GDNF signaling via Ret, contributing to HD pathogenesis.

Animals↗
PubMed1998

Total colonic aganglionosis.

The authors describe the genetic, pathophysiology, diagnostic, and therapeutic aspects of total colonic aganglionosis and of aganglionosis extending to the small intestine. The pathogenesis of this disease is genetically determined and is related to the differentiation and migration of cells derived from neural crests. The clinical and radiological features can be useful in the diagnosis but they are not pathognomonic. The histochemical estimation of acetylcholinesterase activity in suction rectal biopsies is useful in establishing the diagnosis; however, the specimens should be examined by an experienced pathologist. The definitive diagnosis of either condition is obtained by performing intraoperative seromuscular biopsies of the rectum, colon, and ileum. From the therapeutic point of view, many surgical techniques have been proposed for the radical treatment of this disease. Some of the techniques have been derived from operations proposed for the treatment of classic Hirschsprung's disease; others have been specifically designed.

Animals↗
PubMed1998

Association of multiple endocrine neoplasia type 2 and Hirschsprung disease.

In a few patients with Hirschsprung disease (HSCR) and no clinical symptoms of multiple endocrine neoplasia type 2 (MEN-2A) or medullary thyroid carcinoma (MTC), missense mutations in the cysteine residues 609 and 620 of the Ret gene have been identified. In several pedigrees with either MEN-2A or familial MTC (FMTC) a documented germline mutation in cysteine 618 or 620 follows the segregation of the disease phenotype. The appearance of the HSCR phenotype in such patients and pedigrees cannot be easily reconciled with the gain of function which is associated with the dominant oncogenic effect of MEN-2A mutations. Gastrointestinal manifestations are known to occur also in association with MEN-2B but, to the best of our knowledge, in only very few cases the intestinal phenotype of MEN-2B has been investigated by enzymo-histochemical techniques, as in the present work. We report an extensive molecular study of patients, two with HSCR and FMTC carrying a Cys620Arg or Ser mutation and two with MEN-2B and gastrointestinal symptoms carrying a Met918Thr mutation. One of the latter two patients showed aganglionosis of the last 5 cm of rectum which caused a congenital megacolon leading to the diagnosis and operation for HSCR. The mutation screening of all the exons of Ret in 3 of these patients did not reveal any additional mutation. Therefore these results do not support the hypothesis of additional constitutional Ret mutations in patients showing association of MEN-2 and HSCR, whilst the histochemical and clinical data in one of these patients indicate that MEN-2B can be associated with a true form of short segment HSCR.

Drosophila Proteins↗
PubMed1998

Ropivacaine in paediatric surgery: preliminary results.

In a double blind study 40 patients, aged 1-9 years, undergoing elective minor surgery were examined and randomly divided in two groups (20 children each). After light general anaesthesia Group 1 received caudal injection of bupivacaine 0.25% 2 mg.kg-1 while Group 2 received 0.2% ropivacaine 2 mg.kg-1. No differences were observed in demographic data, HR, BP and duration of surgery; the onset time of anaesthesia was 12 min and 9 min in Group 1 and 2 respectively. Ten patients in Group 1 received paracetamol in the first 24 h after surgery while only two children in Group 2 needed analgesic; even the duration of analgesia in the patients requiring paracetamol was superior in group 2 (520 min vs 253 min). No motor block was apparent at awakening in either group and no side effect was noticed. In conclusion ropivacaine seems to be an effective and safe drug in paediatric regional anaesthesia.

Amides↗
PubMed1998

Plasma levels of clonidine following epidural bolus injection in children.

BACKGROUND: The use of clonidine as an adjunct to epidural administration of local anesthetics in children has been reported to substantially improve the duration and quality of postoperative analgesia. The aims of the present study were to determine the pharmacokinetic profile and to investigate the interaction between postoperative sedation and analgesia after epidurally administered clonidine in children. METHODS: Plasma levels of clonidine (0-10 h postop) and assessment of postoperative analgesia and sedation (0-24 h postop) were performed at predetermined intervals following lumbar epidural administration of bupivacaine 2.0 mg/kg and clonidine 2 mg/kg in 8 children undergoing ureteral re-implantation surgery using general anesthesia (age range: 1-9 yr, weight range: 9-41 kg). Plasma levels of clonidine were analyzed by radioimmunoassay, and sedation and analgesia were assessed by previously described scoring systems. RESULTS: The venous plasma pharmacokinetics of clonidine following epidural administration showed a considerable interindividual variation. Cmax and Tmax values of clonidine were found to be within the 0.45-0.77 ng/mL and 48-193 min range, respectively. The time to absorb 95% of the clonidine dose from the epidural space into plasma varied between 36 min and 7.6 h. In 6 of the 8 patients postoperative analgesia substantially outlasted the duration of sedation (> or = 2 h). Sedation could not be detected in any patients at plasma concentrations below 0.3 ng/mL. CONCLUSIONS: The pharmacokinetic profile associated with epidural clonidine administration in children (1-9 y) was similar to that previously reported in adults. The postoperative analgesia seen after administration of epidural bupivacaine-clonidine during general anesthesia in children cannot only be explained by residual postoperative sedation.

Adrenergic alpha-Agonists↗
PubMed1998

[Constipation and chronic intestinal pseudoobstruction as a clinical expression of intestinal neuronal dysplasia (IND)].

BACKGROUND: Intestinal neuronal dysplasia (IND) belongs to the group of dysganglionosis. It may occur as part of a syndrome of early chronic constipation, neonatal intestinal occlusion, chronic intestinal pseudo obstruction. The aim of this study was to report the cases examined by the Istituto G. Gaslini in Genoa and to discuss the numerous aspects of this disease which are still unclear. METHODS: 787 children were included in the study and underwent biopsy between 1984 and 1997. Rectal biopsies were obtained by suction or in some cases during surgery and were treated using enzymohistochemical techniques, such as acetylcholinesterase, rapid acetylcholinesterase and alpha-naphthylesterase. RESULTS: 574 children were found to be suffering from innervative alterations: 348 (60.6%) presented isolated Hirschsprung's disease, IND was found in 83 (14.5%), in 8 of the latter in association with other dysganglionosis. IND was accompanied by other diseases in 40 cases (48.2%). Over the past three years (since October 1994) a total of 164 dysganglionosis have been diagnosed, including 55 cases of aganglia. During this period IND was the most frequently observed alteration and affected 61 children. CONCLUSIONS: Rectal biopsy is the essential diagnostic test for the diagnosis of intestinal dysganglionosis. Biopsies are performed in outpatient clinics without sedation, and do not represent an invasive procedure for the young patients. Radiological and manometric examinations cannot provide reliable data for the diagnosis of IND. In our experience, the incidence of IND over the past few years has increased and its diagnosis is essential for correct treatment which is not surgical in the majority of cases. The real incidence of IND and its pathogenesis still need to be clarified.

English Abstract↗
PubMed1997

The surgical approach to oesophageal achalasia.

The term "oesophageal achalasia" describes a neuropathic disorder characterized by abnormal motility of the oesophagus and incomplete or absent relaxation of the lower oesophageal sphincter. In these patients with "paroxysmal" dysphagia, barium swallow and manometric study confirm the diagnosis. In our opinion, the treatment of choice is extramucosal tardiomyotomy (Heller) which should be followed by gastric fundoplication in order to protect the mucosa and prevent gastrooesophageal reflux. We present our experience in the laparoscopic approach to Heller cardiomyotomy in children. An anterior 180 degrees hemi-fundoplication, according to Dor technique, is performed suturing the left and right oesophageal muscular margin to the gastric wrap. A manometric examination is mandatory in order to detect the complete incision of the lower oesophageal sphincter and to confirm the creation of the new-high pressure zone. This preliminary experience confirms that the laparoscopic approach can be used for the treatment of oesophageal achalasia also in children.

Adolescent↗
PubMed1997

[Congenital deformities of the chest wall. Surgical treatment].

BACKGROUND AND AIMS: Malformations of the front chest wall are congenital defects that have been reported since the seventeenth century and which include the clinical syndromes of funnel chest, pigeon chest and Poland's syndrome. Although they have been reported for such a long time, their pathogenesis is in many ways still unknown and the theories proposed up until now reveal uncertain and unsatisfactory findings. Attempts to gather precise information regarding their real incidence are equally ineffective given that frequently those cases which are not particularly severe are not referred for specialist care. These malformations usually involve severe psychological problems caused by the deformity and, in more severe cases, may lead to alterations in normal cardiac and respiratory function which are above all evident during intense physical effort. METHODS: The authors critically review the cases of chest malformation corrected by the Department of Pediatric Surgery at the G. Gaslini Institute during the period from 1986 to date. They describe the surgical techniques used, justifying their choice and discussing any postoperative complications. RESULTS: This experience shows that there is a clear preference for less invasive surgery for the correction of funnel chest compared to the technique proposed by Ravitch in which the sternum was totally mobilised following its extensive detachment from the other bone and muscular structures of the thoracic cage, with a high risk of damaging the internal mammary artery. The operation that was felt to be most suitable for correcting this defect was that described by Wesselhoett and De Luca in 1982. It is easier to perform and less invasive: it eliminates the detachment phase by inserting a support in titanium alloy through the sternal frame. Autologous grafts taken from the bottom contralateral ribs to the defect were used to treat Poland's syndrome in line with the technique suggested by Ravitch, thus achieving good stability of the whole chest; in view of the young age of the patients undergoing correction, it was not thought appropriate to proceed with the cosmetic reconstruction of the pectoral muscles using a peduncled flap of latissimus dorsi. A total of 70 patients were operated in this way; the cosmetic results were very satisfactory, whereas complications were limited to 5 cases of intraoperative pneumothorax, 5 cases of serohematic subcutaneous collection which were treated conservatively, and 1 case of hypertrophic scarring.

Child↗
PubMed1996

Ret protein in the human fetal rectum.

A major gene for Hirschsprung's disease (HD) recently has been mapped in chromosome 10q11.2 and identified to be the RET proto-oncogene. Mutations of the RET gene have occurred in HD patients, and abnormalities of expression and function of Ret protein (a receptor tyrosine kinase, which is the product of the RET gene) have been found in their intestines. In vitro studies of the biological effects of HD mutations suggest a loss of function effect, which may be negative-dominant. However, the developmental role of the Ret protein in the organogenesis of the enteric nervous system (ENS) and its role in the pathogenesis of HD remain unclear. The authors present a study of the expression of Ret protein in the human ENS during fetal development. Fresh rectal tissues were obtained from nine fetuses (gestational age range, 12 to 22 weeks). Ret protein expression was studied immunohistochemically, using antibodies against the carboxy-terminal 20 amino acids (anti-Ret C) and the extracellular domain (anti-Ret R5). The tyrosine kinase activity of the fetal ENS was investigated with antiphosphotyrosine mouse monoclonal antibody against the phosphorylated tyrosine residues. Anti-Ret C immunostaining was observed in ganglion cells at all ages, but intense activity was significantly higher among the cells of the younger fetuses. Intense anti-Ret R5 immunostaining was present in the enteric ganglion cells of the 12-week-old fetus. The tyrosine kinase activity of ganglion cells increases progressively with advancing gestational age. The results of this study support the hypothesis that the Ret protein receptor might play a crucial role in the cellular and molecular processes involved in the development and maturation of the ENS, abnormalities of which could result in HD. High Ret protein expression and low tyrosine kinase activity have been reported to occur in small ganglia of the HD hypoganglionic segment. In the present study, these markers were typical of the primitive and immature ENS during the early phase of hindgut development.

Animals↗
PubMed1996

Clonidine-mepivacaine mixture vs plain mepivacaine in paediatric surgery.

In a double-blind study, 42 children, aged 1-10, undergoing general subumbilical surgery, were randomly allocated to two groups; they received, via caudal extradural, 1% mepivacaine 7 mg.kg-1 and normal saline 1 ml (Group 1) and a mixture of 1% mepivacaine 7 mg.kg-1 plus clonidine 2 micrograms.kg-1 and normal saline up to 1 ml (Group 2) respectively. No significant difference was noticed in age, weight, duration of surgery and onset time of anaesthesia, blood pressure, heart rate and oxygen saturation. Mean duration of analgesia (evaluated with 'Broadman objective pain scale') was 143 min for Group 1 and 218 min for Group 2 (P < 0.05); the time of sedation (evaluated with a sedation score) was statistically longer in Group 2 (172 min vs 89 min in Group 1). This longer sedation is due both to the longer analgesia and partially to a side effect of clonidine. In conclusion the addition of 2 micrograms.kg-1 of clonidine to mepivacaine prolongs the duration of caudal analgesia in children.

Adjuvants, Anesthesia↗
PubMed1996

[Sedation, combined anesthesia, and total intravenous anesthesia (TIVA) with propofol in the pediatric surgical patient].

Total intravenous anaesthesia (TIVA) has recently obtained a wide diffusion in paediatrics, thanks to the pharmacological properties of propofol. The authors make a review on sedation, combined anaesthesia and Tiva in paediatric anesthesia, particularly on propofol and its characteristics. They describe the practical use of TIVA with recent knowledge in this field.

Anesthesia, Intravenous↗
PubMed1996

[Protective efficacy of 3 anesthetic methods with reference to surgical stress in children].

Hormonal-metabolic stress responses have beyond doubt an effect on morbidity/mortality related to surgery. The present study med to determine which anaesthetic technique could afford the best protection in children, through analysis of the perioperative cortisol, prolactin and beta-endorphin plasma levels. Thirty-six young patients 3-10 years old, ASA I-II, scheduled for hypospadias or vesicoureteral reflux surgery of a duration > 60 min, were randomized into three groups (n = 12). Children of group I were given initially propofol and fentanyl then isoflurane 1%; group 2 received TIVA with propofol and fentanyl, group 3 received initially propofol then an epidural lumbar block with bupivacaine 0.25% (single shot) and continuous propofol i.v. infusion. Cortisol, prolactin and beta-endorphin levels increased significantly in group 1 only. No significant differences were observed between group 2 and 3. Early postoperative analgesia was better in group 3. These data suggest that TIVA and particularly epidural block could afford a better protection against the surgical stress in children submitted to subumbilical operations.

Anesthesia, General↗
PubMed1996

[Surgical implications of familial polyposis coli].

Surgical treatment of familial congenital polyposis (FCP) is deemed necessary as soon as diagnosis is obtained. The goals of any surgical procedure must be: removal of all adenomatous tissue, reliable prophylaxis of cancer, good quality of life. Among the different procedures (proctocolectomy with ileostomy, total colectomy with ileo-rectal anastomosis and postoperative endoscopic surveillance, ileo-rectal pull-through) we consider Soave ileo-endorectal pull-through as the treatment of choice. Between 1974 and 1993, 14 patients, 12 to 40 years old, underwent an ileo-endorectal pull-through (in 4 cases as secondary procedure after ileo-rectal anastomosis performed elsewhere). We had only two major complications, ileal perforation in one case and breakdown of ileo-rectal anastomosis in another case that needed permanent ileostomy. Continence is good in all patients (safe for the one with ileostomy) with an average of three bowel movements per day. Prophylaxis of cancer must be considered complete and permanent without need of surveillance.

Adenomatous Polyposis Coli↗
PubMed1995

Immunohistochemical localization of RET protein in Hirschsprung's disease.

A major gene causing Hirschsprung's disease was recently mapped in 10q11.2. Its physical localization was restricted to a 250-Kb interval containing the RET proto-oncogene (REarranged during Transfection). In 1994, point mutations affecting the RET proto-oncogene were identified in patients with Hirschsprung's disease. The authors present an immunohistochemical study on the expression and localization of the Ret protein (a receptor tyrosine kinase, which is the RET proto-oncogene product) in the intestinal plexuses of patients with Hirschsprung's disease. Ninety-two full-thickness intestinal wall pieces from 29 pediatric patients were studied (19 cases of classic Hirschsprung's disease, 5 of total colonic aganglionosis, and 5 controls). Ret protein immunohistochemical localization was obtained using c-Ret R5, anti-Ret K and anti-Ret C antibodies, respectively, against the extracellular domain, the tyrosine kinase domain, and the carboxy-terminal 20 amino acids of the Ret protein. A diffuse granular staining was present in the ganglia of normal colon, whereas the small ganglia of the hypoganglionic colon showed a reduced number of ganglion cells that were strongly stained with c-Ret R5 MoAb. A reduced synthesis of Ret protein was shown in the ganglionic and hypoganglionic segments of two cases of this series, the first with a complete deletion of the RET proto-oncogene and the second with a frameshift mutation and a stop codon in the extracellular domain. The activity of the receptor tyrosine kinases (RTKs) in intestinal ganglion cells was investigated using antiphosphotyrosine antibodies. A very low tyrosine kinase activity was shown in the small ganglia of the hypoganglionic segment.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed1994

Wilms' tumor arising in a multicystic kidney.

We describe a child with Wilms' tumor (WT) which occurred in an unequivocal multicystic dysplastic kidney (MDK). We indicate a current nonsurgical approach to MDK, but stress the probable malignant degeneration of blastemal cells, the need to search carefully for the WT in the MDK, and the necessity on 3-monthly follow-up US studies.

Follow-Up Studies↗
PubMed1994

Long-gap oesophageal atresia: a combined endoscopic and radiologic evaluation.

The final aim of the treatment of oesophageal atresia is to restore continuity without the interposition of intestinal segments. The authors present the results of a new diagnostic method combining endoscopy and radiology to evaluate the development of pouches in oesophageal atresia. This new method has been successfully adopted in four patients aged between 4 and 8 months, three with type I and one with type III complicated atresia. Direct end-to-end anastomosis was performed in all patients. We think this method can be easily applied and is a suitable diagnostic examination in all cases in which surgical strategy aims at restoring oesophageal continuity by means of direct anastomosis.

Anastomosis, Surgical↗