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Ermanno Ancona

Publications and source records attributed to Ermanno Ancona.

25 records · Page 2Linked to original sources

Understanding of and attitudes to xenotransplantation: a survey among Italian university students.

UNLABELLED: Xenotransplantation is currently at the experimental stages on animal models and many problems still have to be overcome in the biomedical, immunological and ethical fields. Moreover, people's attitudes to xenotransplantation vary: surveys among intensive-care staff have revealed negative opinions, while the general public and students seem to be more positive. Little is known about the influence of schooling and the choice of university faculty on attitudes to xenotransplantation. The aims of this study were: (i) to evaluate university students' attitudes to xenotransplantation; (ii) to investigate any socio-demographic, religious and educational determinants behind students' opinions on xenotransplantation. University undergraduates on five different courses were surveyed at Padua University. A 24-item questionnaire was distributed to students at the end of lectures and completed anonymously immediately after its distribution. No information was given to students beforehand. STATISTICAL ANALYSIS: chi-squared, Pearson's test; P-values <0.05 were considered significant. A total of 585 of 602 (97.2%) students completed the questionnaire (132 males, 453 females, mean age 20.4, range 19 to 43 yr). They were on courses in Medicine (33.85%), Agriculture (5.98%), Veterinary Medicine (11.45%), Psychology (18.46%) and Educational Sciences (30.26%). As for their previous schooling, they came from classical or scientific high school (58.3%), technical college (14.7%), language college (6.3%), teacher training college (11.9%) or others (8.8%). Concerning their religious beliefs, 83% were Catholics, and 56.2% defined themselves as practising Catholics. Eighty-eight percentage of the students knew of the possibility of animal organs being transplanted into humans and 77.9% of them approved of this idea. When grouped according to gender and education, a higher proportion of students approving of xenotransplantation were male (P = 0.017) and had attended classical or scientific high school (P = 0.011). Disapproval for moral, ethical or religious reasons was higher among practising than among non-practising Catholics; the latter rejected xenotransplantation more for immunological and infectious reasons (P = 0.014). As for the type of university course, a higher proportion of students approving of xenotransplantation attended science courses (Veterinary Medicine, Agriculture and Medicine vs. Educational Sciences and Psychology) (P = 0.013). University students generally approved of xenotransplantation. Male gender and a high-school education were associated with a greater acceptance of xenotransplantation. Practising vs. non-practising Catholics reported significantly different reasons for any disapproval of xenotransplantation. The choice of a science rather than an arts faculty at university was more strongly associated with a positive opinion on xenotransplantation.

Adult↗

Ureteral stenosis in HDAF pig-to-primate renal xenotransplantation: a phenomenon related to immunological events?

The aim of this study was to analyze the incidence of ureteral stenosis in a life-supporting human decay-accelerating factor (hDAF) transgenic pig-to-cynomolgus monkey kidney transplantation model and determine the role of possible immunological events in its pathogenesis. Thirty consecutive bi-nephrectomized cynomolgus monkeys received a kidney from hDAF transgenic pigs with or without a ureteral stent. Four monkeys were euthanized prematurely after transplantation. In the remaining 26 cases, the mean survival was 24 +/- 19 days. Except in one case, there was a close relationship between ureter and kidney in terms of type and severity of rejection. There were six ureteral stenoses; five were repaired by stent positioning and resurgery extended survival for an additional 16 +/- 10 days. The stenotic ureters showed diffuse acute humoral xenograft rejection (AHXR), while all cases with no or only focal signs of ureteral rejection never revealed ureteral obstruction. Use of a ureteral stent extends the survival of a xenografted primate, thereby helping to clarify the immunological events surrounding the onset of AHXR in kidneys in long-term xenograft recipients.

Animals↗

Methotrexate for immunosuppression in life-supporting pig-to-cynomolgus monkey renal xenotransplantation.

Methotrexate (MTX) has been used successfully as an immunosuppressant in rodent xenotransplantation models, but the data generated so far with MTX in pig-to-baboon cardiac transplantation studies have been disappointing. The potential of this agent was consequently explored in a life-supporting pig-to-primate renal model using the cynomolgus monkey as the recipient species. Introductory in vitro and in vivo pharmacokinetic and pharmacodynamic studies with MTX were conducted in three cynomolgus monkeys. Subsequently, 10 cynomolgus monkey recipients of a life-supporting kidney from human decay-accelerating factor transgenic pigs were administered MTX intravenously according to three different regimens. All the animals also received cyclosporine A and steroids. In addition, mycophenolate sodium (MPS) was administered post-operatively in two of the three groups of transplanted animals. At clinically relevant concentrations, MTX is able in vitro to inhibit the mixed lymphocyte reactions (MLR) in cynomolgus monkeys. After intravenous administration, moreover, exposure of cynomolgus monkeys to MTX appeared to be higher than had been previously reported in baboons. Graft function was observed in the transplanted animals, which survived from 0 to 41 days. All but two animals revealed acute humoral rejection in the explanted graft and developed diarrhea. Diarrhea was the cause of euthanasia in five cases. It was unrelated to the administration of MPS and associated with severe histopathological signs of enteritis. This study demonstrates that the pharmacokinetic and pharmacodynamic profiles if MTX vary substantially between non-human primate species. In vitro, MTX has immunosuppressive properties in the cynomolgus monkey at clinically relevant concentrations. In vivo, MTX has a very narrow therapeutic window in cynomolgus monkeys, however, as it does in baboons. We conclude that MTX is scarcely effective as an immunosuppressant, be it for induction or maintenance, in pig-to-cynomolgus monkey renal xenotransplantation.

Animals↗

Etiology, diagnosis, and treatment of failures after laparoscopic Heller myotomy for achalasia.

OBJECTIVE: To assess the causes of failure of laparoscopic Heller myotomy and to verify whether endoscopic pneumatic dilation is a feasible treatment. SUMMARY BACKGROUND DATA: Laparoscopic Heller myotomy has proved an effective treatment for esophageal achalasia, with good or excellent results in 90% of patients. The treatment of failures remains controversial, however. METHODS: From 1992 to 1999, 113 patients underwent laparoscopic Heller myotomy for esophageal achalasia. Ten patients (8.7%) reported dysphagia (n = 7) or chest pain (n = 3) a median of 5 months after surgery (range 1-12) and were considered surgical failures. Pre- and postoperative radiologic, manometric, and 24-hour pH monitoring findings in patients with achalasia recurrence were compared with those of 74 asymptomatic subjects. RESULTS: The preoperative characteristics of the two groups were comparable. After surgery, a decrease in resting lower esophageal sphincter pressure was observed in both groups, whereas the abdominal and overall lengths were significantly shorter among the asymptomatic patients. No patients with recurrence had abnormal gastroesophageal reflux. Based on time to recurrence and manometric and fluoroscopic findings, the etiology of the recurrences was classified as incomplete myotomy upward (n = 1), incomplete myotomy or sclerosis of the myotomy downward (n = 7), or sigmoid megaesophagus (n = 1); in one patient the authors could not establish the etiology. Seven of nine patients were effectively treated with endoscopic pneumatic dilations (median 2 dilations, range 1-4); one refused to undergo further treatment. Two patients underwent redo surgery. CONCLUSIONS: Recurrence of symptoms after myotomy is mainly related to incomplete myotomy or sclerosis of the distal site of the myotomy; it can be treated by dilations after surgery.

Adolescent↗

Xenotransplantation, where do we stand?

Xenotransplantation is currently being investigated as a possible solution to the world-wide shortage of human organs. Several major advances have unquestionably been accomplished in the last decade in this field. These include an elucidation of the immunological mechanisms underlying the rejection of pig organs transplanted into primates, the generation of novel lines of genetically-engineered pigs that are more "compatible" with man and a better understanding of the risk of zoonosis related to the transmission of porcine endogenous retroviruses to primates. Though very encouraging, the existing preclinical data do not entitle clinical trials with pig organs to begin as yet and, for the time being, the use of human organs remains the only viable option for patients with terminal organ failure.

Animals↗

[Multimodal treatment in locally advanced esophageal cancer: a multicenter phase II study with neoadjuvant oxaliplatin, 5-fluorouracil, leucovorin and neoadjuvant radiotherapy: preliminary results].

The aim of the study was to evaluate the feasibility and efficacy of treatment with oxaliplatin, 5-fluorouracil and leucovorin concomitant with radiation therapy in locally advanced oesophageal cancer. Fifty-eight patients with previously untreated, histologically proven oesophageal cancer were enrolled. Downstaged patients underwent either surgery or received brachytherapy. We report the results obtained in the first 54 patients. The median age was 58 years. The diagnosis was squamous cell carcinoma/adenocarcinoma/poorly differentiated: 45/8/1; clinical stage: T3N1M0 38 (70%), T4 10 (19%), M1a 6 (11%). Thirty-nine patients (72%) received the planned 8 weeks of chemotherapy and 45 completed the entire course of scheduled radiotherapy. Four (7%) toxic deaths were recorded, 2 more patients died prematurely from massive oesophageal bleeding and 1 from progression of disease. We recorded 8 (15%) complete responses and 24 (44%) partial responses. Resection was complete (R0) in 24 (80% of resected patients, 44% of treated patients). A complete pathological response was documented in 6 patients (11% of those treated). Postoperative complications were recorded in 8 (25%) patients, with 2 (6.2%) deaths. RO resection was accomplished in 44% of patients. Toxicity was moderate, but postoperative mortality was not negligible. Survival data are awaited before a phase III comparison with cisplatin-containing chemo-radiotherapy may be considered.

Adult↗