An engineered U1 small nuclear RNA rescues splicing defective coagulation F7 gene expression in mice.

BACKGROUND: The ability of the spliceosomal small nuclear RNA U1 (U1snRNA) to rescue pre-mRNA splicing impaired by mutations makes it an attractive therapeutic molecule. Coagulation factor deficiencies due to splicing mutations are relatively frequent and could therefore benefit from this strategy. However, the effects of U1snRNAs in vivo remain unknown. OBJECTIVES: To assess the rescue of the F7 c.859+5G>A splicing mutation (FVII+5A), causing severe human factor VII (hFVII) deficiency, by the modified U1snRNA+5a (U1+5a) in a murine model. METHODS: Mice expressing the human F7 c.859+5G>A mutant were generated following liver-directed expression by plasmid or recombinant adeno-associated viral (AAV) vector administration. The rescue of the splice-site defective pre-mRNA by U1+5a was monitored in liver and plasma through hFVII-specific assays. RESULTS: Injection of plasmids encoding the U1+5a rescued plasma hFVII levels, which increased from undetectable to ~8.5% of those obtained with the wild-type hFVII plasmid control. To assess long-term effects, mice were injected with low and high doses of two AAV vectors encoding the FVII+5A splice site mutant as template to be corrected by U1+5a. This strategy resulted in hFVII plasma levels of 3.9 ± 0.8 or 23.3 ± 5.1 ng mL⁻¹ in a dose-dependent manner, corresponding in patients to circulating FVII levels of ~1-4.5% of normal. Moreover, in both experimental models, we also detected correctly spliced hFVII transcripts and hFVII-positive cells in liver cells. CONCLUSIONS: Here we provide the first in vivo proof of-principle of the rescue of the expression of a splicing-defective F7 mutant by U1snRNAs, thus highlighting their therapeutic potential in coagulation disorders.

Methotrexate in paediatric ulcerative colitis: a retrospective survey at a single tertiary referral centre.

BACKGROUND: Patients with ulcerative colitis often receive thiopurines as immunomodulators (IMs) to maintain remission and avoid corticosteroids. If unresponsive or intolerant to these agents, patients are treated with methotrexate, an antimetabolite never assessed in paediatric ulcerative colitis. AIM: To describe the experience with methotrexate in children with ulcerative colitis. METHODS: Thirty-two patients (median age 13.9 years) received methotrexate. Pediatric Ulcerative Colitis Activity Index (PUCAI) and use of corticosteroids were the main outcomes evaluated at baseline and at 3, 6 and 12 months. RESULTS: Indications to methotrexate were azathioprine unresponsiveness in 18 patients, azathioprine intolerance/toxicity in 10 and spondyloarthropathy in four. Response or remission was achieved in 72%, 63% and 50% of patients at 3, 6 and 12 months respectively. Mean PUCAI were 49.5 ± 23.3 at baseline and 32.9 ± 21.9, 29.5 ± 21.8 and 29.4 ± 19.9 at 3, 6 and 12 months respectively (P: 0.03). At the beginning of methotrexate, 16 patients (50%) received corticosteroids that were discontinued in 13 of them (81%) by 6 months. At the end of the study, 11 patients (33%) needed short courses of corticosteroids for disease relapse. CONCLUSIONS: Methotrexate may be useful in treating children with ulcerative colitis, although large, controlled trials are warranted to define better its effectiveness.

Inability of University of Wisconsin solution to reduce postoperative peritoneal adhesions in rats.

OBJECTIVE: To examine the effect of University of Wisconsin solution (UWS) on the formation of postoperative peritoneal adhesions. DESIGN: Laboratory experiment. SETTING: University hospital, Italy. ANIMALS: 42 Sprague-Dawley rats. INTERVENTIONS: A standard lesion was made consisting of serosal trauma of the caecum and a parietal peritoneal defect. Rats were randomly divided into seven groups (n = 6 each): the first group acted as controls; the second had instilled normal saline 6 ml; the third Ringer's lactate 6 ml; the fourth UWS 6 ml; the fifth normal saline 12 ml; the sixth Ringer's lactate 12 ml; and the seventh UWS 12 ml. MAIN OUTCOME MEASURES: Adhesions were scored two weeks later for extent (0 to 4) and type (0 to 4). Adhesion strength was measured by a tensiometer. RESULTS: The mean (SEM) scores for extent and type of adhesions were significantly lower (p < 0.05) after instillation of Ringer's lactate 12 ml [1.0 (0.4) and 1.2 (0.4), respectively] than controls [3.5 (0.3) and 2.7 (0.2), respectively]. Adhesions were also significantly weaken (p < 0.05) [101 (33) g] than in controls [207 (6) g]. CONCLUSIONS: Intraperitoneal instillation of normal saline and UWS were ineffective in reducing the extent and type of adhesions. Although Ringer's lactate produced a significant reduction in severity, the effect was strongly volume related. This amount of fluid may be detrimental to a patient's postoperative course.

[Phlebodynamometry in the study of venous insufficiency of the lower limbs]. / La flebodinamometria nello studio dell'insufficienza venosa degli arti inferiori.

BACKGROUND: The significance of ambulatory venous pressure measurement in the diagnosis of chronic venous insufficiency of the lower limbs is evaluated. METHODS: 190 limbs of 120 outpatients were investigated from 1991 through 1997; the study was performed whenever clinical and ultrasound evaluation did not allow to establish the diagnosis of "simple varices". The technique standardized according to Nicolaides was followed. RESULTS AND CONCLUSIONS: The results of the study confirm the importance of ambulatory venous pressure measurement in the differential diagnosis of chronic venous hypertension of the lower limbs, especially when caused by vein compression, as well as in the follow-up of these patients when submitted to surgical treatment.

Functional and morphological evaluation of canine veins following preservation in different storage media.

Injuries of endothelial and smooth muscle cells of autologous vein due to preservation in standard storage media may be responsible for graft failure. The effects of vein preservation with University of Wisconsin solution (UWs) on endothelial and smooth muscle cell function and morphology were compared to the effects of preservation with autologous whole blood (AWB) and normal saline (NS), which are frequently used in cardiovascular surgery. Canine external jugular and common femoral vein segments were preserved in the different solutions at 4 degrees C for 45 min and 24 hr. Rings (4-5 mm in length) from control and preserved veins were evaluated by isometric tension studies at 37 degrees C and by scanning and transmission electron microscopy. Differences between groups were evaluated by Student's t test or Mann-Whitney U test and by analysis of the variance, and considered to be significant at P < 0.05. Sensitivities to norepinephrine (NE) showed that a 45-min vein storage in AWB (5.7 +/- 0.2 mumol/L) but not in NS (5.8 +/- 0.2 mumol/L) or UWs (6.5 +/- 0.2 mumol/L) had a deleterious effect on function of smooth muscle (P < 0.05) when compared to control veins (6.6 +/- 0.2 mumol/L). Maximum contractile responses and sensitivities to NE were significantly altered (P < 0.05) after 24-hr vein storage in AWB (0.09 +/- 0.02 g/mm2 and 5.4 +/- 0.07 mumol/L) and NS (0.12 +/- 0.03 g/mm2 and 5.6 +/- 0.08 mumol/L) but not in UWs (0.36 +/- 0.06 g/mm2 and 6.4 +/- 0.07 mumol/L). With both storage times, acetylcholine-induced endothelium-dependent maximum relaxations and sensitivities were significantly reduced (P < 0.05) in veins stored in AWB and NS, but not in UWs, compared with controls. Similarly, transmission electron microscopy revealed marked neutrophil migration beneath the intimal surface of vessels and extensive separation and desquamation of endothelial cells with exposure of subendothelial structures in veins stored in AWB and NS. The results suggest that UWs is a suitable storage medium when compared to AWB and NS.

Short-term preservation of autogenous vein grafts: effectiveness of University of Wisconsin solution.

BACKGROUND: Suboptimal preservation of autologous veins in storage solutions causes endothelial cell damage that can contribute to graft failure. The purpose of this study was to compare the effects of short-term storage of veins in autologous whole blood (AWB), 0.9% normal saline solution (NS), and University of Wisconsin solution (UWs) on vein structure and function after grafting. METHODS: Autogenous jugular and femoral veins were atraumatically harvested from mongrel dogs. One vein segment was immediately implanted to serve as a control, and the other segments were stored for 45 minutes in AWB, NS, or UWs. The veins were implanted as reversed interposition graft in the carotid or femoral arteries. After 6 weeks light and scanning electron microscopy and isometric tension studies were performed on explanted vein grafts. RESULTS: Morphologic studies revealed an intact endothelium that stained positively for factor VIII. Intimal thickness was similar between controls (48 +/- 12 microns) and veins stored in UWs (53 +/- 8 microns) (p = not significant), but it was significantly increased in veins stored in AWB (151 +/- 29 microns) and NS (149 +/- 18 microns) (p < 0.05). Sensitivity and maximum contraction to norepinephrine were not altered in veins preserved in UWs (6.0 +/- 0.1 mumol/L and 0.19 +/- 0.02 gm/mm2) but were significantly reduced (p < 0.05) in those stored in AWB (7.2 +/- 0.1 mumol/L and 0.08 +/- 0.02 gm/mm2) and NS (7.0 +/- 0.3 mumol/L and 0.09 +/- 0.02 gm/mm2) compared with controls (5.9 +/- 0.2 mumol/L and 0.20 +/- 0.02 gm/mm2). The sensitivity and maximum relaxation to acetylcholine and sodium nitroprusside of veins preserved in AWB, NS, and UWs were similar to controls (p = not significant). CONCLUSIONS: Vein storage in UWs preserves smooth muscle cell function compared with veins stored in NS or AWB. Therefore UWs is a more suitable medium for short-term preservation of veins in cardiovascular operation.

International registry of inferior vena cava leiomyosarcoma: analysis of a world series on 218 patients.

In 1992 The International Registry of Inferior Vena Cava (IVC) Leiomyosarcomas was established to study the pathogenesis and natural history of the tumor and to support the most rational treatment. We collected 218 patients through a literature review and personal communications. We corresponded with several Authors to obtain up-to-date follow-up and any other data lacking at the initial review. The series was analyzed to identify predictive factors for clinical outcome. Tumors arose from the IVC lower segment in 80 patients, from the middle in 94 and from the upper in 41. A radical tumor resection was undertaken in 134 (61.5%) patients, 26 (11.9%) had a palliative resection and 58 (26.6%) were inoperable. An increased risk of death was associated with upper IVC segment involvement (p < 0.001), lower limb edema (p < 0.001), Budd-Chiari's syndrome (p < 0.001), intraluminal tumor growth (p < 0.001) and IVC occlusion (p < 0.001). Radical tumor resection was associated with better 5- and 10-year survival rates (49.4% and 29.5%). Tumors which arose from the middle segment fared better (56.7% and 47.3%) than those of the lower segment (37.8% and 14.2%) (p < 0.002). No palpable abdominal mass and abdominal pain were associated, in patients radically operated, with a better outcome and longer survival (p < 0.03 and p > 0.04 respectively). Despite the high rate of recurrence, radical tumor resection is the only long-term cure.

Ischemia-induced peripheral arterial vasospasm role of alpha 1- and alpha 2-adrenoceptors.

Ischemia produces functional and structural alterations in peripheral blood vessels. Our study was designed to investigate alpha-adrenoceptor modifications induced by prolonged ischemia and their role in enhancing the contractile response during reperfusion in canine femoral arteries. Unilateral vessel ischemia was created by double crossclamping a femoral artery and was maintained for 3 hr. Reperfusion was allowed for 1 hr. The contralateral femoral artery was utilized as a control. The vessels were harvested for contractile and binding studies. Isometric tension studies revealed that the magnitude of the maximum contractile response to norepinephrine (NE), potassium chloride (KCl), and methoxamine was 671 +/- 82 mg/mm2 versus 245 +/- 43 mg/mm2 (P < 0.01), 485 +/- 46 mg/mm2 versus 229 +/- 62 mg/mm2 (P < 0.05), and 486 +/- 88 mg/mm2 versus 126 +/- 38 mg/mm2 (P < 0.01), respectively for ischemic and nonischemic femoral arteries. EC50 values showed that ischemic vessels were more sensitive to NE, KCl, and methoxamine (P < 0.05). Sodium nitroprusside induced concentration-dependent and complete relaxation in all arterial rings (100% relaxation) but the ischemic femoral artery showed less sensitivity (P < 0.05). Binding studies showed that the number of binding sites (Bmax) for [3H]Prazosin and [3H]Rauwolscine were significantly increased in ischemic versus nonischemic vessels (1261 +/- 95 fmole/mg versus 704 +/- 113 fmole/mg, P < 0.03, and 490 +/- 86 fmole/mg versus 175 +/- 15 fmole/mg, P < 0.04, respectively). Furthermore, a significant decrease in affinity (Kd) for [3H]Prazosin and [3H]Rauwolscine was observed in ischemic versus nonischemic tissues (9.4 +/- 1.7 nM versus 4 +/- 0.2 nM, P < 0.02, and 6.4 +/- 1.5 nM versus 1.8 +/- 0.6 nM, P < 0.01, respectively). The increase in canine femoral artery vasoreactivity, following prolonged ischemia, seems to be also due to an increased density and functional activity of alpha-adrenoceptors expressed by the ischemic arterial smooth muscle cells.

Femoral artery aneurysms: long-term follow-up and results of surgical treatment.

Aneurysmal dilatation of the femoral artery is a rare condition of uncertain aetiology. Between January 1972 and December 1992, 31 atherosclerotic femoral aneurysms in 22 patients were seen. There were 21 men and 1 woman; mean(s.d.) age was 70.1(10.4) years. Thirteen (42%) femoral aneurysms (group 1) were isolated aneurysms, two being bilateral. Eighteen (58%) were associated with a non-contiguous abdominal aortic aneurysm, four being unilateral and seven bilateral femoral aneurysms (group 2). The mean(s.d.) size of these aneurysms was 4.7(1.5) and 3.5(0.7)cm in groups 1 and 2 respectively (P< 0.01). Of the limbs in group 1,12 were treated by an interposition bypass. A ruptured profunda femoris artery aneurysm was ligated in one limb as an emergency operation. All patients in group 2 underwent an aortobifemoral graft. There was one operative death. Three early thromboses were observed; two autogenous saphenous vein interposition grafts and one limb of an aortobifemoral. One late thrombosis occurred in an expanded polytetrafluoroethylene graft in group 1. The five-year patency rate was 80% for group 1 and 88.9% for group 2 (P=n.s.). The overall 10-year limb salvage rate was 100%. These findings suggest that isolated femoral aneurysms are larger and more frequently symptomatic than femoral aneurysms associated with an abdominal aortic aneurysm. The association between femoral aneurysm and abdominal aortic aneurysm was found to be higher in patients with bilateral femoral aneurysms compared with those with unilateral lesions (P< 0.05). In the treatment of isolated femoral aneurysms better early results were obtained with expanded polytetrafluoroethylene interposition grafts.

Fresh vein allograft survival in dogs after cyclosporine treatment.

Synthetic grafts are widely used for peripheral arterial reconstructions when autologous veins are not available, but their results have not been satisfactory. Venous allograft may be used as an alternative to synthetic prostheses. The aim of the study was to explore the immunosuppressive efficacy of Cyclosporine A (CyA) as a means of preventing venous allograft failures and rejection. We utilized 56 mongrel dogs. Immunological incompatibility was checked with the skin graft method. Donor inferior vena cava was transplanted into the infrarenal abdominal aorta of recipient animals. One group (group 1, 10 dogs) served as a control and three groups received CyA treatment regimens. Group 2 (10 dogs) received postoperative oral CyA treatment for 30 days. Group 3 (12 dogs) received a vein graft pretreated with a CyA solution without postoperative immunosuppressive therapy. Group 4 (9 dogs) received a vein graft pretreated with a CyA solution and postoperative CyA treatment for 30 days. Allografts were examined at 30 days for patency, aneurysmal dilatation, gross structural changes, inflammatory response, and lymphocytic infiltration. Sex chromatine assessment determined the origin (donor or recipient) of the endothelial cells. The allografts from groups 1 and 3 showed significant aneurysmal dilatation and perivenous inflammation when compared to dogs treated with oral CyA therapy (P < 0.0002). Moreover allografts treated with CyA therapy had a better-developed venous neointima (P < 0.009) with less fibrin (P < 0.02) and thinner medial (P < 0.0009) with less fibrin (P < 0.02), and thinner medial (P < 0.0009) and adventitial layers (P < 0.02). No significant differences were observed in neointimal thickness among the four groups. Lymphocytic infiltration was greater in the group of animals who did not receive oral CyA therapy (P < 0.0004). Barr bodies status showed significant differences between oral CyA treated groups and nontreated groups (P < 0.0003). Oral CyA therapy reduced aneurysmal dilatation and immunological response, promoted the development of a neoendothelium, and preserved the structure of the venous layers. Graft pretreatment with CyA flushing did not have a significant immunosuppressive effect.

Long-term outcome after transaxillary approach for thoracic outlet syndrome.

BACKGROUND: Recurrence or persistence of neurologic symptoms after surgical treatment of patients with thoracic outlet syndrome (TOS) are reported to be as high as 25%. To identify factors affecting the long-term outcome of surgical treatment of patients with TOS, we reviewed our 20-year experience. METHODS: One hundred thirty-four transaxillary first rib resections were performed on 118 patients (43 men, 75 women, mean age 38 +/- 13 years). Eighty-three operations (61.9%) were undertaken to relieve symptoms resulting from compression of the lower roots of the brachial plexus, 37 (27.6%) for compression of both lower and upper roots, and 14 (10.5%) for lower root and vascular symptoms. All patients underwent a transaxillary extraperiosteal first rib resection with transection of the scalene muscles. In 73 cases (54.5%) a resection of the anterior scalene muscle was also performed. A cervical rib was removed in 28 cases (20.1%), and anomalous fibrous bands adjacent to the neurovascular bundle were resected in 41 cases (30.6%). RESULTS: No major complications were observed. Of 105 patients (118 procedures) followed up (mean follow-up, 99 +/- 72 months), good to excellent results were obtained in 96 cases (81.4%) and fair to poor results were recorded in 22 cases (18.6%). The presence of a long posterior first rib stump, measured from the chest x ray films, was the strongest determinant of the long-term results among the variables examined (p < 0.0001). Reoperation, consisting of neurolysis and resection of the stump, was performed in 16 patients. The results were excellent in all cases at a mean follow-up of 66 +/- 46 months. Primary and secondary 10-year, actuarial freedom rates from recurrent symptoms were 80.9% and 93.1%, respectively. CONCLUSIONS: Our results suggest that the long-term outcome after surgery for TOS was strongly influenced by the extent of the first rib resection.

University of Wisconsin solution effects on intimal proliferation in canine autogenous vein grafts.

This study was carried out to investigate if the University of Wisconsin solution (UWs) is suitable for long-term preservation of autogenous vein grafts (AVG) prior to transplantation, compared to autologous whole blood (AWB) and normal saline (NS). Autogenous jugular and femoral veins were harvested from adult mongrel dogs, using a "no-touch" technique. One segment of vein was immediately implanted to serve as a control, while other segments were stored for 24 hr at 4 degrees C in AWB, NS, or UWs. The control and the preserved veins were implanted as reversed interposition grafts in the common carotid or femoral artery positions. After 6 weeks, scanning electron microscopy revealed an intact endothelial cell monolayer in all vein grafts that was stained positively for factor VIII. The degree of intimal thickening, as assessed by light microscopy in the middle position of the grafts, was similar in controls (52.0 +/- 15.8 microns) and in veins stored in UWs (58.5 +/- 16.1 microns), but it was significantly increased (P < 0.05) in veins preserved in NS (198.9 +/- 19.5 microns) and in AWB (312.0 +/- 171.6 microns). Isometric tension studies revealed that maximum contraction and sensitivities (assessed by EC50) to norepinephrine were significantly reduced (P < 0.05) in AVG stored in AWB (0.05 +/- 0.02 g/mm2 and 5.5 +/- 2.8 microM), but not in UWs (0.16 +/- 0.03 g/mm2 0.92 +/- 0.34 microM) and NS (0.09 +/- 0.03 g/mm2 and 3.0 +/- 1.1 microM), compared with controls (0.17 +/- 0.03 g/mm2 and 0.99 +/- 0.38 microM). Acetylcholine (Ach)-induced maximum relaxations were similar in all of the veins.(ABSTRACT TRUNCATED AT 250 WORDS)

[Carotid thromboendarterectomy: personal experience and review of the literature]. / Tromboendoarterectomia carotidea: esperienza personale ed analisi della letteratura.

Carotid endoarterectomy (CEA) is known to prevent cerebrovascular accidents. Between February 1987 and December 1993 we performed 97 CEA on 82 patients (62 male and 20 female, median age 66 +/- 7.6 years) 95.1% reported previous hemispheric neurological accidents; 4.9% were asymptomatic. Operative indications for asymptomatic patients were high degree stenosis (> 70%) of the internal carotid artery and ulcerated plaques with a moderate degree (50%) of stenosis. Major events (transient ischemic attack and stroke) were recorded in 73.2% cases. Preoperative investigations consisted of Duplex scan, arteriography, and cerebral CT scan or NMR. Operative mortality was 2.06% (2 cases) and perioperative stroke was 5.1% (5 cases). The sensibility, sensitivity and accuracy of Duplex scan to detect ulcerated plaques was 88.7%, 85.2% and 87.5% respectively. At a median follow-up of 33 months (range 6-81 months) 74 (92.5%) patients are free of strokes whereas 1 patient died for stroke. In our series the annual incidence of stroke was 0.5%. Our results suggest that Duplex scan is a reliable exam to investigate the carotid axis and CEA is a safe operation that prevents future cerebrovascular accidents.

Seasonal variation in the incidence of ruptured abdominal aortic aneurysm.

In order to determine any possible influence of climatic variables on the incidence of abdominal aortic aneurysm rupture, we reviewed 49,144 autopsies performed in two major hospitals in Rome, Italy, from January 1956 to March 1986. There were 297 subjects who were found to be sufferers of atherosclerotic abdominal aortic aneurysm for a prevalence of 0.6%. The aneurysm was intact in 220 cases (74%) and ruptured in 77 cases (26%). The highest incidence of ruptured aneurysm occurred during the Autumn and in the months May and July. The incidence of ruptured aneurysm was highest in case of significant changes of the atmospheric temperature. There was no correlation between the incidence of ruptured aneurysm and barometric pressure or humidity.

Comparative long-term results of laser-assisted balloon angioplasty and atherectomy in the treatment of peripheral vascular disease.

BACKGROUND: Early results of laser-assisted balloon angioplasty (LABA) and peripheral directional atherectomy (PDA) are encouraging. The true value of these procedures has remained in doubt, however, because of the absence of data on long-term objective patency rates. PATIENTS AND METHODS: From August 1988 through October 1993, LABA and PDA were performed on 151 limbs of 124 patients. Presenting symptoms were mild-to-severe claudication in 128 limbs (63 LABA, 65 PDA) and rest pain or necrosis in 23 (7 LABA, 16 PDA). Seventy-seven percent of the atherosclerotic lesions were localized in the iliofemoral tract (77% LABA, 76% PDA). Seventy limbs were treated with LABA and 81 with PDA. RESULTS: Initial hemodynamic and arteriographic success was achieved in 46 LABA limbs (66%) and 75 PDA limbs (93%) (P < 0.002). Mean follow-up was 16 +/- 2 months after LABA and 18 +/- 1 months after PDA. During this time, 32 failures were recorded in limbs treated with LABA, and 29 in limbs treated with PDA. The patency rate at 40 months was 23% in the LABA group and 45% in the PDA group (P < 0.005). Patency rates were not affected by the length or site of the arterial lesion or the runoff score. CONCLUSIONS: PDA had a better long-term patency rate than LABA, but long-term results were dismal with both techniques. PDA appears to have a limited role and LABA no role in the treatment of lower extremity occlusive disease.

Functional and morphological assessment of rat aorta stored in University of Wisconsin and Eurocollins solutions.

University of Wisconsin (UW) and Eurocollins (EC) solutions are widely used for preservation of organs before transplantation. However, effect of storage solutions on vascular interface for transplant success is not known. In this study, we have used rat aorta as a model and assessed the effects of cold storage in UW and EC solutions on smooth muscle and endothelial function and the morphology. Smooth muscle and endothelial functions of the rat aorta were assessed using in vitro isometric tension measurement. Morphologic studies were done with scanning and transmission electron microscopy. No significant difference in contractile response to either norepinephrine (NE) or potassium chloride was observed between control aorta and aorta stored in UW solution for 1 hr or 24 hr. In contrast, sensitivity, but not the reactivity to NE and KCl, was increased in aorta stored in EC solution for 1 hr. If the tissues were stored in EC solution for 24 hr, both sensitivity and reactivity to NE and KCl were significantly reduced. Relaxatory response to acetylcholine, in endothelium-intact vessels were reduced in aortas stored in EC solution, but not in UW solution. The magnitude of relaxations observed in tissues stored in the EC solution for 24 hr was less than in tissues stored for 1 hr. Sodium nitroprusside elicited similar relaxatory response in endothelium-denuded control tissue and in tissues stored in UW and EC solution. Electron microscopy data revealed marked swelling of the cell, loss of mitochondria and other intracellular organelles, and striking calcium deposits after preservation of the vessels in EC for 1 or 24 hr. In aorta stored in UW solution for 24 hr, endothelial and smooth muscle cells were intact, with moderate-size vacuoles in the cytoplasm. These results suggest that the UW solution is more suitable than EC solution for short-term preoperative storage of blood vessels.

Factors influencing the rupture of abdominal aortic aneurysms.

The gross findings of 49,144 autopsies performed at two major hospitals in Rome were reviewed. There were 297 patients who were found to have atherosclerotic abdominal aortic aneurysm (AAA). The aneurysm was intact in 220 (74 per cent) and ruptured in 77 (26 per cent). The occurrence of aneurysm rupture was correlated to 17 variables by univariate and multivariate statistical analysis. Covariates found to be independently predictive of the rupture of AAA were the size of the aneurysm (p less than 0.001), arterial hypertension (p less than 0.001) and the presence of bronchiectasis (p less than 0.025.). Over-all, bronchiectasis was more common among patients with AAA than in the age-adjusted and sex-adjusted control population. The simultaneous presence of bronchiectasis and AAA suggests the presence of some inherited or acquired tendency to have ectasia of the connective tissue, aneurysm formation and rupture development.