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C Redaelli

Publications and source records attributed to C Redaelli.

At least 37 records · Page 2Linked to original sources
PubMed1998

Prolongation of allograft survival by 1,25-dihydroxyvitamin D3.

BACKGROUND: 1,25-Dihydroxyvitamin D3, the hormonal form of vitamin D, is now believed to play a significant role in the immune responses, both in vitro and in vivo, preventing the development of several autoimmune diseases. These studies suggest that 1,25-dihydroxyvitamin D3 may be effective in prolonging allograph survival. METHODS: To test the hypothesis that 1,25-dihydroxyvitamin D3 would prolong allograft survival, neonatal heart grafts were transplanted to allogeneic recipients receiving either 19-nor-1,25-dihydroxyvitamin D2 (200 ng/day) or 1,25-dihydroxyvitamin D3 (50 ng/mouse/day) orally through the diet. The efficacy of 1,25-dihydroxyvitamin D3 in prolonging graft survival in a vascularized model was determined by heterotopic ACI to Lewis heart transplants. RESULTS: The provision of exogenous 1,25-dihydroxyvitamin D3 or an analog, 19-nor-1,25-dihydroxyvitamin D2, to mice markedly prolonged the survival of neonatal mouse heart allografts. Similar results were obtained with a vascularized heterotopic heart transplant model in rats. Cyclosporine at a maximum 25 mg/kg dose for mice proved less effective than 1,25-dihydroxyvitamin D3. Graft survival in mice differing at class I and class II loci (B10.A(4R) --> C57BL/10) increased from 13.0+/-1.1 days to 51.0+/-5.6 days and was significantly better than cyclosporine monotherapy (33.2+/-3.6). Rat heart survival in a high responder strain combination (ACI --> Lewis) increased from 6.2+/-0.3 to 25.2+/-2.8 days. The increased survival of the transplants brought about with 1,25-dihydroxyvitamin D3 was not accompanied by hypercalcemia in rats. CONCLUSION: These results suggest that 1,25-dihydroxyvitamin D3 can be used as an effective agent in preventing graft rejection.

Animals↗
PubMed1998

1,25-Dihydroxyvitamin D3 prolongs graft survival without compromising host resistance to infection or bone mineral density.

BACKGROUND: Recently, we have shown that 1,25-dihydroxyvitamin D3 prolongs graft survival in mice and rats when the donor and recipient differ at two or more major histocompatability loci. Among the most serious side effects encountered with the currently available transplantation antirejection drugs are an increased susceptibility to infection and decreased bone mineralization. Our results suggest that 1,25-dihydroxyvitamin D3 prolongs graft survival without these side effects of bone loss and susceptibility to infection. METHODS: We compared the ability of 1,25-dihydroxyvitamin D3-treated, nontreated, or cyclosporine (CsA)-treated mice to resist infection with Candida albicans and herpes simplex virus-1. To determine bone density, femurs were collected from nontreated, 1,25-dihydroxyvitamin D3-treated (50 ng/mouse/day), or CsA-treated (25 mg/kg/day) mice, and bone ash was determined. RESULTS: Here we show that 1,25-dihydroxyvitamin D3 treatment does not increase the susceptibility of the host to fungal or viral infection. Furthermore, CsA causes bone loss, whereas 1,25-dihydroxyvitamin D3 actually increases bone mass. CONCLUSIONS: The use of 1,25-dihydroxyvitamin D3 and its analogs to increase transplant survival will avoid bone loss and opportunistic infection, two important disadvantages of the most widely used transplant antirejection drugs--CsA and the glucocorticoids.

Animals↗
PubMed1998

Role of thromboxane and leukotriene B4 in patients with acute respiratory distress syndrome after oesophagectomy.

We have studied prospectively the clinical course and serum concentrations of thromboxane B2 (TxB2) and leukotriene B4 (LTB4) in patients developing adult respiratory distress syndrome (ARDS) after oesophagectomy. The clinical course was assessed according to a validated ARDS score, and intra- and postoperative measurements of TxB2 and LTB4 in pre- and post-pulmonary blood were performed in 18 patients undergoing oesophagectomy for oesophageal carcinoma and 11 control patients undergoing thoracotomy and pulmonary resection. Six of 18 patients undergoing oesophagectomy, but no control patient, developed ARDS. The ARDS score was highest on day 8 after operation. Only patients with ARDS had a significant postoperative increase in post-pulmonary, but not pre-pulmonary, TxB2 concentrations (P < 0.05 vs patients without ARDS). This study provides evidence that TxA2, originating from the lungs, was associated with the development of ARDS after oesophageal resection. In view of the high incidence of ARDS after oesophagectomy (10-30%), prophylactic treatment of patients undergoing oesophageal resection with clinically applicable thromboxane synthetase inhibitors may be warranted.

Adult↗
PubMed1997

First clinical experience with fundus rotation gastroplasty as a substitute for the oesophagus.

BACKGROUND: Leakage of oesophagogastric anastomosis has been associated with poor perfusion of the gastric tube. The authors recently developed a new form of gastroplasty, preserving not only the arterial arcade along the greater curvature, but also the lesser curvature. In this study their first clinical experience with that gastric tube is reported. METHODS: Thirty-five patients undergoing either oesophagectomy or laryngopharyngo-oesophagectomy for malignant lesions and substitution of the oesophagus with a funds rotation gastroplasty were included. Patient outcome, including anastomotic leak, hospital mortality and morbidity rates, were studied prospectively. RESULTS: Hospital mortality rate was one of 35 and anastomotic leak (one minor, one moderate) was found in two patients with no subsequent mortality. Further major morbidity included pulmonary dysfunction in the form of acute respiratory distress syndrome (ARDS) in seven patients. Mean (s.e.m.) hospital stay was 27(19) days, and 21(9) days in patients who did not develop ARDS. CONCLUSION: Fundus rotation is a new method of gastroplasty that allows safe anastomosis of the tube with the remaining oesophagus or pharynx and is associated with a low leak rate even at high cervical levels.

Adenocarcinoma↗
PubMed1997

Splanchnic microcirculatory changes during CO2 laparoscopy.

BACKGROUND: Splanchnic macrocirculatory changes during high-pressure CO2 pneumoperitoneum include a decrease in mesenteric arterial blood flow, and decreased gastric perfusion with a drop in gastric pH in experimental studies. Microcirculatory changes in abdominal organs under clinical conditions with a low pressure CO2 pneumoperitoneum are unknown. STUDY DESIGN: In 18 patients undergoing routine laparoscopy with a CO2 pneumoperitoneum (7 symptomatic cholecystolithiasis, 3 acute cholecystitis, and 8 acute appendicitis) gastric, duodenal, jejunal, colonic, hepatic, and peritoneal blood flow was measured with a custom-made laser Doppler flow probe at an intra-abdominal pressure of 0, 10, and 15 mm Hg. RESULTS: Intra-abdominal pressure elevation from 10 mm Hg to 15 mm Hg significantly decreased the blood flow in the stomach by 40 percent to 54 percent, the jejunum by 32 percent, the colon by 44 percent, the liver by 39 percent, the parietal peritoneum by 60 percent, and the duodenum by 11 percent. Splanchnic blood flow decreased with operative time at a constant intra-arterial pressure (r = 0.88, p < 0.0001). CONCLUSIONS: From our study, we concluded that laparoscopic procedures with a CO2 pneumoperitoneum should be performed at a pressure of 10 mm Hg or lower to avoid splanchnic microcirculatory disturbances.

Adolescent↗
PubMed1996

Gastric microcirculatory changes during gastric tube formation: assessment with laser Doppler flowmetry.

Poor perfusion of the gastric substitute in esophageal replacement frequently causes anastomotic break down. In this in vivo study we assessed gastric microperfusion before, during, and after gastric tube formation by means of laser Doppler flowmetry in 11 patients undergoing esophagectomy for esophageal cancer. Baseline blood flux along the greater curvature was 323 +/- 57, 167 +/- 28, and 190 +/- 44 perfusion units (PU) and along the lesser curvature 222 +/- 44 and 227 +/- 46 PU. Blood flux was significantly higher in close proximity to tumor-infiltrated areas (819 +/- 172 and 879 +/- 119 PU, P < 0.03 and P < 0.008 compared to normal stomach). Dissection of the gastrocolic ligament and the left gastric artery reduced gastric blood flux along the greater curvature to 69 +/- 21, 79 +/- 19, and 155 +/- 61 PU. Elongation and transformation of the stomach to a gastric tube further reduced blood flux in the stomach especially at the fundus. In this study laser Doppler flowmetry was a valuable tool to assess microcirculatory changes during gastric tube formation as well as pathological blood flow in tumor bearing areas of the stomach in vivo. Quantification of the perfusion of gastric tubes in esophageal replacement might help prevent ischemia-induced anastomotic breakdown.

Adenocarcinoma↗
PubMed1993

[Paraplegia, a catastrophic complication of interventions on the infrarenal aorta].

Damage to the spinal cord in course of the treatment of diseases of the infrarenal aorta is a rare but calamitous complication. The reported incidence is about 0.2%. The neurological loss is usually complete flaccid paraplegia with high mortality and rare full or partial recovery. Between 1980 and 1991, 1070 reconstructive procedures of the infrarenal aorta were performed: 821 due to aneurysm (316 elective procedures [mortality 1.6%] and 505 emergency procedures [mortality 24.5%]) and 249 due to aorto-iliac occlusive disease. Damage to the spinal cord occurred in 2 patients (2/1070, 0.19%). One patient had incomplete paraparesis following repair of an unruptured abdominal aortic aneurysm with gradual return of all neurological symptoms to normal. The second patient developed complete paraplegia following repair of a ruptured infrarenal aneurysm. There war no recovery of the symptoms. The patient died from septicaemia 4 months later.

Aged↗
PubMed1993

Ruptured abdominal aortic aneurysms: predictors for early complications and death.

BACKGROUND: Urgent operation for ruptured aneurysm is still associated with a high operative mortality rate. The purpose of the study was to determine the risk factors that truly influence early complications and death. METHODS: Between 1979 and 1991, 314 consecutive patients with a mean age of 69 years were treated surgically for a ruptured infrarenal abdominal aortic aneurysm. Twenty-two preoperative, perioperative, and intraoperative variables were subjected to a multivariate analysis to identify the independent predictors. RESULTS: Early death occurred in 92 (29%) of 340 patients. Significant primary predictors for early death were duration of cross-clamp (p < 0.0001), preoperative shock (p = 0.0005), suprarenal cross clamp (p = 0.002), and a history of coronary artery disease (CAD) (p = 0.004). The following postoperative complications were risk factors for death: myocardial failure (p < 0.0001), renal failure (p < 0.0001), sepsis (p = 0.01), and colon ischemia (p = 0.03). Predictors for postoperative myocardial insufficiency were a history of CAD (p < 0.0001), amount of intraoperative volume substitution (p < 0.0001), suprarenal cross clamp (p = 0.0007), and preoperative shock (p = 0.05). CONCLUSIONS: Preoperative and perioperative risk factors that result in fatal postoperative complications can be partially influenced by the surgeon. Short clamping time and infrarenal position of aortic clamp may lower overall early mortality rates. A history of CAD is a highly significant predictor for postoperative complications and early death.

Aged↗
PubMed1992

[The deltoid flap-plasty. Therapy of choice in large rotator cuff ruptures?].

Rotator cuff tear is an extremely common and important disease. An extensive rotator cuff tear is an incapacitating event and remains a major problem which forces to respect to the management. The late outcome of majors ruptures of such tears are often a defect-arthropathy with a complete destroy of the shoulder and a loss of flexibility caused by pain. The deltoid muscle plasty, as the logical reconstruction method and relatively easy to perform, lead to better results in compare to all the variety of surgical treatments of restoring the anatomical continuity. This article reviews the clinical manifestations, operative technique and the results associated with the treatment by deltoid muscle plasty. Based on the results. Based on the results of flexibility, and postoperative pain in shoulder we conclude that the early results in our group of the first 20 patients are excellent. 84% of the patients were subjectively very satisfied and free of pain.

Aged↗
PubMed1992

[Rupture of the Achilles tendon--fibrin gluing or suture?].

The rise of recreational sports activities and the incidence of ruptures of the Achilles tendons has increased simultaneously. Recently the use of fibrin sealing for surgical therapy of ruptured Achilles tendons has emerged as an alternative technique. Between 1982 and 1989 62 consecutive patients were operated for unilateral Achilles tendon rupture. Following causes for ruptures are known: 36 indirect traumas in sport (74%), 9 direct blunt injuries at occupational work (18%), 3 traffic-accidents (11%) and 1 rupture after operation of a Haglund exostosis. 25 patients (56%) were treated by suture technique and 20 patients (44%) with fibrin sealant. The mean long term follow-up of 49 months is known of 49 patients. There were 3 (12%) postoperative infections in the suture group and none in the fibrin group. After suturing the Achilles tendon 3 (12%) reruptures occurred 8-10 weeks after tendon repair and 1 (5%) rerupture after fibrin sealing. All reruptures are caused by a new adequate trauma. The time of return to social and recreational activities was 9 months in the suture group and 7 months in the fibrin group. The functional and cosmetic results after use of fibrin was significant better, and the long-term results were very satisfactory. We prefer fibrin sealing for the treatment of acute ruptures of Achilles tendons.

Achilles Tendon↗
PubMed1992

[Valve replacement in patients over 80 years of age].

Between January 1983 and October 1990, 20 patients age 80 years or older (mean 82 +/- 1.5 year, range 80 to 87 years) underwent valvular surgery at Clinic for Cardiovascular Surgery Zurich. The indication for operation was aortic stenosis in 19 patients, and mitral insufficiency after previous mitral valve replacement with a bioprosthesis in one. There were 15 elective operations, 2 urgent, and 3 emergency operations. Four of these patients had aortic valve replacement plus coronary artery bypass grafting. The operative mortality rate was 15% (3 patients). All patients were preoperative in NYHA classes III and IV. All survivors remained in NYHA classes I or II. The survivors have been followed from 6 to 70 months (mean 20 +/- 8 months). The actuarial survival rate at 1 and 5 years was 78.5% and 67%, respectively. Valvular replacement can be performed with increased but acceptable mortality and morbidity. Long-term results are encouraging.

Aged↗
PubMed1992

A novel class of cholinergic agents structurally related to 2-morpholinol.

A series of esters and ethers of N-alkylmorpholin-2-ols, and their methiodides, which can be considered cyclic analogues of acetylcholine, were synthesized. The amines were obtained by acylation or etherification of morpholinols with the appropriate acyl chlorides and alcohols. All compounds were tested for their ability to interact with the muscarinic receptor M2 (guinea-pig atria) or M3 (rat ileum and urinary bladder) subtype. Some compounds, although endowed with relatively low potency, proved interesting for their organ selectivity. Some considerations on the structure-activity relationship are made and the results obtained with reference agonists and antagonists are also shown.

Animals↗
PubMed1992

[Blood substitution in aorto-iliac surgery].

To determine the amount of blood substitution required we evaluated in a retrospective analysis 68 consecutive patients that were operated on the infrarenal abdominal aorta 1990, 60 men with a mean age of 66 years (40-87) and 8 women, aged 73 years (62-85). Indications for treatment were: aneurysm (55) and occlusive disease (13). 21 aneurysms (45%) were ruptured and had to be operated as an emergency. Early lethality (less than 30 days) in this group was 19% (n = 4). In the other 47 patients there was no early mortality. Mean blood products transfusion requirements in patients with ruptured abdominal aortic aneurysm was: 18 (9-34) units of concentrated red cells, 16 (3-43) units of fresh frozen plasma (FFP) and 5 (0-19) units of concentrated red cells, 2 (0-7) units of FFP in the elective group. Main determinants of blood loss in the elective group were: the number of anastomoses and the preoperative status of the coagulant system. We conclude that in elective surgery of the infrarenal aorta homologous transfusion can be virtually eliminated if an entire autologous transfusion concepts is applied (predonation, intraoperative salvage, hemodilution and plasmapheresis).

Aged↗