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R Castellano

Publications and source records attributed to R Castellano.

At least 19 recordsLinked to original sources
PubMed2005

Visceral artery aneurysms.

Visceral artery aneurysms (VAA) frequently present as life-threatening emergencies. The purpose of this study was to review our experience with VAA treatment. Between 1988 and April 2002, 31 VAA were treated in 28 patients (14 males, 14 females) with average age of 55 +/- 15 years. The most common locations were the splenic artery (16) and the hepatic artery (7). Three patients underwent emergency surgery, 22 patients had elective open surgery, and 7 patients underwent endovascular treatment. In the surgical group the perioperative mortality rate was 3.6%. The perioperative morbidity rate was 7.1% (one case of respiratory distress manifested in the immediate postoperative period and one urgent case of bilious fistula). In the endovascular group none of the patients died; the perioperative morbidity rate was of 14.3% (one case of hepatic artery thrombosis after failure of gastroduodenal artery aneurysm embolization). Failure of the procedure was 42.9% (3 cases of aneurysm recanalization). In conclusion, we believe that an aggressive surgical approach is justified, even in the case of asymptomatic VAA, because of the low morbidity and mortality rates. Endovascular treatment should be reserved for selected cases.

Abdomen↗
PubMed2004

Vanin-1-/- mice exhibit a glutathione-mediated tissue resistance to oxidative stress.

Vanin-1 is an epithelial ectoenzyme with pantetheinase activity and generating the amino-thiol cysteamine through the metabolism of pantothenic acid (vitamin B(5)). Here we show that Vanin-1(-/-) mice, which lack cysteamine in tissues, exhibit resistance to oxidative injury induced by whole-body gamma-irradiation or paraquat. This protection is correlated with reduced apoptosis and inflammation and is reversed by treating mutant animals with cystamine. The better tolerance of the Vanin-1(-/-) mice is associated with an enhanced gamma-glutamylcysteine synthetase activity in liver, probably due to the absence of cysteamine and leading to elevated stores of glutathione (GSH), the most potent cellular antioxidant. Consequently, Vanin-1(-/-) mice maintain a more reducing environment in tissue after exposure to irradiation. In normal mice, we found a stress-induced biphasic expression of Vanin-1 regulated via antioxidant response elements in its promoter region. This process should finely tune the redox environment and thus change an early inflammatory process into a late tissue repair process. We propose Vanin-1 as a key molecule to regulate the GSH-dependent response to oxidative injury in tissue at the epithelial level. Therefore, Vanin/pantetheinase inhibitors could be useful for treatment of damage due to irradiation and pro-oxidant inducers.

Amidohydrolases↗
PubMed2003

Carotid endarterectomy in the octogenarian: outcomes of 345 procedures performed from 1995-2000.

The purpose of this study is to evaluate the efficacy and the safety of carotid endarterectomy (CEA) in the octogenarian patient. From January 1995 to December 2000, we have performed 3430 CEAs in 2743 patients: 345 CEAs in 269 octogenarian patients (Group 1) and 3085 CEAs in 2474 younger patients (Group 2). Age was the only selection criteria for including patients in Group 1. Octogenarians' perioperative mortality (1.4%) was greater than that in Group 2 (0.3%) (p<0.05). No differences can be found between the groups' perioperative ipsilateral stroke rates (1.7% in Group 1 vs 1.2% in Group 2) and combined ipsilateral stroke and death rates (2.3% in Group 1 vs 1.3% in Group 2) (p>0.05). The octogenarians' Kaplan-Meier 6-year overall and free-stroke survival rates were 86 and 76% respectively. CEA can be performed in selected octogenarian patients with low early and late mortality and neurologic morbidity rates.

Age Factors↗
PubMed2003

Traumatic rupture of the thoracic aorta.

Traumatic rupture of the thoracic aorta is a life threatening situation, and may be secondary to several mechanisms; mainly penetrating or iatrogenic lesions and blunt trauma. Although penetrating mechanisms predominate, the number of patients with aortic disruption due to blunt trauma has continued to increase. This paper shows an overview focusing on the pathogenesis, diagnosis, timing and type of treatment regarding traumatic injuries of the thoracic aorta; it also reports the experience of one single center that deals with these lesions. The major difficulty in the evaluation data on blunt aortic injury is that retrospective reviews often group together patients with all types of aortic lesions, comparing outcomes for injuries in different locations, with diverse methods of repair and different surgeons and/or institutions.

Adolescent↗
PubMed2002

Vascular prosthetic graft infection: epidemiology, bacteriology, pathogenesis and treatment.

UNLABELLED: Vascular prosthetic graft infection remains a major surgical challenge. Prevention of risk factors and antibiotic therapy can reduced but not eradicate it. Management of infected vascular grafts depends on several factors, including the location of the infected prosthesis, the extent of infection, and the underlying micro-organism. Classic treatment consists of extra-anatomic bypass grafting. The disappointing results due to the high mortality and amputation rate have kindled interest in alternative approaches, such as in situ reconstruction with antibiotic-bonded prostheses, autogenous veins or arterial allografts. PURPOSE: We focused on the treatment of aortic graft infection by means of both fresh and cryopreserved arterial allograft. Here, the experience of the Italian Collaborative Vascular Homograft Group is reported. METHODS: Between March 1994 and December 2000 seventy-nine patients with aortic graft infection were treated. The results of 68 patients are analysed. Eleven patients were treated with fresh, and 57 with cryopreserved homograft. Emergency surgical procedures were performed in 12 patients (17%). Aortoenteric fistula was diagnosed in 22 patients. The mean interval between the first procedure and the insertion of a homograft for patients with infected aortic graft was 3 years (range 1-15). The mean duration of follow-up was 30 months (range 1-68). Clinical and duplex scanning evaluation were routinely performed. Computer tomography (CT), magnetic resonance (MR), or arteriography were performed on the basis of duplex scanning results. RESULTS: The analysis was performed on 68 cases for which there were sufficient reliable data. Eleven deaths occurred during the early postoperative period (30 days), a mortality rate of 16%. There were also seventeen late deaths, a mortality rate of 25%. Eleven patients had graft occlusion; six cases were successfully treated with thrombectomy. In three cases leg amputation was necessary. The results of fresh and cryopreserved homografts were compared. No significant differences of early postoperative mortality, late mortality, homograft-related mortality, graft failure were observed. The presence of aortoenteric fistula is a negative predicting factor of perioperative early mortality, which causes a rapid decline in the survival curve. Thirty-six months after the surgery the actuarial survival of the patients was 57% and the actuarial patency of the allograft was 41%. CONCLUSION: No significant difference in terms of clinical outcome was observed when using fresh, rather than cryopreserved homografts. The only factor that significantly influenced the survival rate appeared to be the aorto-enteric fistula.

Anti-Bacterial Agents↗
PubMed2000

Extensible expanded polytetrafluoroethylene vascular grafts for aortoiliac and aortofemoral reconstruction.

The operative experience and medium-term outcome achieved with longitudinally extensible ('stretch') expanded polytetrafluoroethylene (ePTFE) bifurcated grafts in patients undergoing aortoiliac or aortofemoral reconstruction for occlusive disease at our institution was reviewed. Between 1991 and 1998, 242 patients received a bifurcated stretch graft. Forty-one patients (17%) required an aortic endarterectomy, and 63 (26%) underwent femoral artery endarterectomy. 228 patients were followed for a mean of 32 months. One patient (0.4%) died perioperatively. The perioperative morbidity included cardiac (3.7%), respiratory (2.5%), and renal (3.3%) complications. Three patients required early reoperation for bleeding. Four (1.7%) grafts thrombosed within 24h of surgery; eight additional grafts (3.3%) thrombosed 5-8 months later. There were three postoperative aortic graft infections, one inguinal infection, three inguinal pseudoaneurysms, and one aortic pseudoaneurysm. Ultrasonography during follow-up showed no periprosthetic fluid collections or graft dilatations. The bifurcated ePTFE stretch graft is suitable for aortoiliac and aortofemoral reconstruction, and its physical characteristics may help to reduce graft-related complications.

Aged↗
PubMed2000

Role of Tec kinase in nuclear factor of activated T cells signaling.

The Tec protein kinase family includes Btk, Itk, Tec, Rlk and Bmx, which are critically involved in signals mediated by various cytokines and antigen receptors. Btk mutations cause severe immunodeficiencies, with defective B cell function. In T cells, Tec regulates cytokine production. However, the downstream targets of these Tec kinases are poorly defined. Here we report that overexpression of Tec in T cells can regulate gene transcription through the nuclear factor of activated T cells (NF-AT). Using different reporter gene constructs, we establish that Tec in transfected T cells dramatically induced NF-AT-dependent gene transcription, which was prevented by a dominant-negative mutant of NF-AT or by the immunosuppressive drug cyclosporin A. Tec appears to regulate NF-AT nuclear import. In addition, Tec influences cytoplasmic free calcium increase. Taken together, our results identify NF-AT as a major downstream target of Tec kinases that is critically involved in transcriptional gene regulation. These observations highlight signaling pathways regulated by Tec kinases and provide new pharmacological targets to regulate immune functions.

Biological Transport↗
PubMed1998

In search of biological markers of high-risk carotid artery atherosclerotic plaque: enhanced LDL oxidation.

The oxidation of low density lipoprotein (LDL) is a key event in the development and progression of atherosclerosis because it generates molecular epitopes that are more atherogenic than parent LDL. We found previously that patients with carotid atherosclerosis have a significantly higher titer of autoantibodies against oxidatively modified LDL than normal subjects. The aim of this study is to correlate biological markers of in vivo LDL oxidation with the degree of carotid stenosis and of plaque ulceration (PU) in a series of patients undergoing carotid endoarteriectomy (CEA). Ninety-four consecutive patients (68M and 26F, aged 67.3 +/- 8.2 years) who underwent CEA at our institution between June 1993 and January 1994 were included in the study. The degree of carotid stenosis and the presence and extent of PU were correlated with the level of autoantibodies (IgG) against oxidatively modified LDL (Cu++-oxidized [oxLDL] or malondialdehyde derivatized LDL [MDA-LDL]), that consistently mirrors the occurrence of oxidative modifications in vivo. A statistically significant correlation (r = 0.23, p = 0.039) was found between the degree of carotid stenosis and antiMDA-LDL specific ratio (a parameter that describes the specificity of LDL towards other proteins as target for oxidative modification). A statistically significant correlation was also found between the PU score and antioxLDL IgG (r = 0.32, p = 0.011), antiMDA-LDL IgG (r = 0.25, p = 0.045) and antiMDA-LDL IgG specific ratio (r = 0.38, p = 0.002). None of the classical biochemical parameters (total, LDL and HDL cholesterol and triglycerides) correlated with the above-mentioned plaque characteristics. The results shown, support the use of biological markers of in vivo LDL oxidation (antioxidatively modified LDL autoantibody titers) to evaluate the clinical setting of high-risk carotid atherosclerosis both in screening and in follow-up studies.

Aged↗
PubMed1998

Antipyrine clearance in chronic and neoplastic liver diseases: a study of 518 patients.

Antipyrine metabolism is widely used as an index of the drug-metabolizing reserve of the liver. It is well known that metabolism of this drug is impaired in subjects with acute hepatitis or cirrhosis, but conflicting data have been reported regarding patients with chronic postinfectious hepatitis or liver cancer. We studied conventional liver-function parameters and antipyrine metabolism (antipyrine per o.s. 18 mg/kg) in 518 subjects. One hundred and one patients had liver metastases (various primaries). Based on the number and size of lesions, the hepatic involvement was considered minimal in 47 and massive in 54 (groups B1 and B2, respectively). One hundred and two had chronic active hepatitis (CAH); 51 patients with histological evidence of fibrosis/early cirrhosis and 51 patients were without histological evidence of fibrosis/early cirrhosis. Ninety-two had histologically confirmed cirrhosis (group D), and the remaining 120 had cirrhosis and hepatocellular carcinoma (group E). The control group was composed of 103 subjects with healthy livers (group A). Antipyrine clearance (AP Cl) in CAH patients with fibrosis (0.246 +/- 0.98 mL/min per kg) was similar to that observed in patients with cirrhosis (0.223 +/- 0.148 mL/min per kg), and both values were significantly lower than that found in CAH patients without fibrosis (0.406 +/- 0.159 mL/min per kg, P < 0.01). Antipyrine clearance in patients with liver metastases (0.426 +/- 0.174 mL/min per kg) was similar to that of the healthy group (0.489 +/- 0.210 mL/min per kg). Cirrhotics and cirrhotics with hepatocellular carcinoma (HCC) presented similar degrees of impairment. Antipyrine clearance was positively correlated with serum albumin (r2 = 0.10, P = 0.01) and prothrombin time (r2 = 0.129, P < 0.01) in all groups, except those with liver metastases. In patients with CAH, the presence of fibrosis/cirrhosis is associated with impaired antipyrine metabolism. The lack of impairment in groups with liver metastases suggests that the functional hepatic reserve is maintained even in the presence of massive neoplastic invasion.

Adolescent↗
PubMed1997

Safe and cost-effective approach to carotid surgery.

OBJECTIVE: To evaluate the safety and cost effectiveness of carotid surgery performed altering the perioperative protocol in an attempt to decrease resource utilisation. SETTING: Department of vascular surgery in a large metropolitan teaching hospital in northern Italy. DESIGN: Prospective, non-selective study. MATERIALS AND METHODS: Three hundred and eighty carotid procedures were performed in 1995 on 343 patients (274 males, 69 females, mean age 68.2 years, range 47-86 years). The most important cost containment measures, were: (i) limiting the use of contrast arteriography to cases of dubious ultrasonographic diagnosis; (ii) routine use of loco-regional anaesthesia; (iii) postoperative admission to an intensive care unit (ICU) only in selected cases; (iv) early postoperative discharge where possible. RESULTS: Mortality was 0.26% and neurological morbidity 1.58%. General anaesthesia was required in eight patients (2.1%), and only seven patients (1.8%) were admitted postoperatively to the ICU. Arteriography was performed in 56 cases (14.7%). The average hospital stay was 5 days with a global cost of 43,036 ECU, as compared with a cost of 6764 ECU for patients treated traditionally with routine arteriography, general anaesthesia and routine ICU admission. CONCLUSIONS: Selective use of arteriography and ICU, routine use of loco-regional anaesthesia and reduced hospital stay make it possible to lower the cost of carotid surgery without sacrificing quality.

Aged↗
PubMed1997

Is endoscopy useful for early diagnosis of ischaemic colitis after aortic surgery? Results of a prospective trial.

BACKGROUND: Ischaemic colitis is an infrequent, but potentially fatal, complication of abdominal aortic surgery. Its presentation is often underestimated on account of a paucity of symptoms, thus the real incidence of ischaemic colitis may be higher. AIM: To determine the prognostic value and sensitivity of endoscopy, early postoperative endoscopic findings were evaluated. METHODS: Over a period of three years a prospective study was undertaken in a consecutive series of 105 patients (mean age 68.9 years, range 51-85) undergoing routine rectosigmoidoscopy within 72 hours of aortic reconstructive surgery. RESULTS: Colonic ischaemia was found in 12 patients (11.4%); five had endoscopic evidence of mild ischaemic colitis, ulcerations were identified in five and diffuse superficial necrosis in two. Seven of the 12 patients were symptomatic. Laparotomy was never deemed necessary and all patients were successfully treated with a conservative regimen. There were no deaths. Elective reconstruction or urgent procedure did not correlate with the development of colonic ischaemia, nor did duration of aortic cross-clamp time, patency of the inferior mesenteric artery and its possible ligation or reimplantation or patency of the hypogastric arteries. CONCLUSIONS: Rectosigmoidoscopy is effective for early diagnosis of ischaemic colitis. Early endoscopy should be routinely performed only for patients in whom impaired blood flow is suspected on the basis of the intraoperative objective assessment of the colon and in presence of symptoms.

Aged↗
PubMed1995

Avidin and 111In-labelled biotin scan: a new radioisotopic method for localising vascular graft infection.

OBJECTIVES: To evaluate a new imaging technique, for diagnosis of prosthetic vascular graft infection. Avidin is a protein which accumulates nonspecifically at sites of inflammation or infection. Due to its extremely low dissociation constant with biotin sites of infection can be imaged, using avidin as a pre-target, followed by injection of 111In-labelled biotin. This technique is much simpler than the common scintigraphic methods which employ labelling of blood components and its target-to-background ratio is greater than the methods employing radiolabelled proteins. DESIGN: Prospective clinical study. SETTING: A single department of vascular surgery and one of nuclear medicine of a Northern Italian hospital. MATERIALS: Between May 1993 and May 1994, 31 grafts in 26 patients were studied; the series included 23 men and three women with a mean age of 65.5 years (range 54-76 years). The prosthetic graft (Dacron -16, ePTFE -15) were: aortoaortic 5, aortobifemoral 15, aortoiliac 1, and femoropopliteal 10. Sixteen patients were suspected of having a vascular graft infection (Group A), the other 10 patients served as controls (Group B). 20 mg of Avidin were injected iv, followed 24 h later by i.v. injection of 500 micrograms of Biotin labelled with 74 MBq of 111In. CHIEF OUTCOME MEASURES: Whole-body imaging was performed at 10 min and 2 h post-injection, along with SPECT imaging when indicated. Scan results were correlated with the traditional imaging modalities and the clinical outcome of the patients. MAIN RESULTS: In Group A: two patients (three grafts) were excluded from the study, there were six true-positives, one false-positive and 11 true-negatives. Results in Group B: 10 true-negatives. The overall sensitivity was 100%, the specificity 95%, the accuracy 96%, the positive predictive value 86% and the negative predictive value 100%. CONCLUSIONS: These data suggest that Avidin/111In-labelled Biotin scintigraphy is a useful non invasive diagnostic method for early diagnosis of suspected prosthetic vascular graft infection.

Aged↗
PubMed1995

Mural thrombi in abdominal aortic aneurysms: MR imaging characterization--useful before endovascular treatment?

PURPOSE: To evaluate magnetic resonance (MR) imaging accuracy in the characterization of mural thrombi in abdominal aortic aneurysms (AAAs). MATERIALS AND METHODS: Forty-five patients (37 men, eight women; mean age, 68 years) with an AAA with mural thrombus thicker than 1 cm at sonography underwent T1- and T2-weighted spin-echo MR imaging. The thrombi were prospectively classified as one of three signal intensity (SI) categories: category 1 corresponds to low SI on both T1- and T2-weighted images; category 2, high SI on T1-and T2-weighted images; and category 3, inhomogeneous SI with hyperintense areas on both T1- and T2-weighted images. During surgery, thrombi were classified as organized, unorganized, and partially organized. MR imaging and surgical findings were compared. RESULTS: SI category 1 corresponded to organized thrombi in 24 of 24 patients. Category 2 corresponded to unorganized thrombi in 11 of 11 patients. In category 3, focal hyperintense areas corresponded (both for presence and location) to unorganized portions of partially organized thrombi in 10 of 10 patients. CONCLUSION: MR imaging is accurate in AAA thrombus characterization.

Aged↗
PubMed1995

A new ePTFE stretch graft for aorto-iliac reconstructions. Surgical evaluation and one year follow-up with magnetic resonance imaging.

Since its introduction at the beginning of the 60s Dacron has proved to be a reliable and durable substitute for aortic reconstructions. It is however susceptible to late thrombosis, infection and aneurysmal dilatation in a significant number of cases. ePTFE vascular prosthesis, introduced in 1972, have proved to perform well for peripheral reconstructions and was used in aortoiliac position since 1980. In 1991 a new type of ePTFE rendered longitudinally extensible (Gore-Tex Stretch) was introduced into clinical practice. The aim of this study is to evaluate surgical performance, short term patency and interaction with periprosthetic tissues of Gore-Tex Stretch straight and bifurcated prosthesis. Between October 1991 and December 1993, 59 patients underwent aortic reconstruction at our Institution either for infrarenal aortic aneurysm (19 patients, 16 males, 3 females, mean age 68.8 +/- 8.5 years) or for aortoiliac occlusive disease (40 patients, 36 males, 4 females, mean age 60.5 +/- 7.2 years). Forty-eight bifurcated and eleven straight grafts were implanted using Gore-Tex sutures. Preoperative workup included Ultrasonography, Magnetic Resonance Imaging (MRI) in patients with aneurysms and Intra Arterial Digital Subtraction Arteriography (DSA) in patients with occlusive disease. Intraoperative parameters were recorded. Postoperative follow-up included ultrasonographic evaluation at 1st and 7th day, 15th postoperative week and at 3 monthly intervals; Intra Venous DSA before dismission and MRI at the 1st and 15th postoperative week. Intraoperatively the grafts proved to be soft and flexible with good handling and suturing characteristics. Perioperative bleeding was 480 +/- 299 ml for occlusive disease cases and 633 +/- 314 for aneurysm cases. No operative mortality was recorded.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

LDL oxidation in patients with severe carotid atherosclerosis. A study of in vitro and in vivo oxidation markers.

Among the various risk factors involved in the development and progression of carotid atherosclerosis, the oxidation of LDL has been proposed to play a relevant role. LDL oxidation has been investigated in 94 patients with severe carotid atherosclerosis undergoing elective carotid artery endarterectomy and in 42 matched control subjects. LDL oxidation was evaluated in all patients as (1) the susceptibility to in vitro oxidation, (2) vitamin E concentration and its efficiency in LDL, and (3) the presence of autoantibodies against oxidatively modified lipoprotein to monitor the occurrence of the oxidative processes taking place in vivo. No difference was detected between control subjects and patients concerning vitamin E concentration and the kinetics of conjugated diene formation in isolated LDL exposed to CuSO4. However, vitamin E efficiency was lower (9.6 +/- 4.2 versus 30.2 +/- 7.6 min/nmol vitamin E) and the duration of the vitamin E-independent lag phase was longer (105.5 +/- 16.5 versus 58 +/- 11.8 minutes) in the patient group. Autoantibodies against oxidatively modified lipoproteins were measured with an ELISA method using native LDL, Cu(2+)-oxidized LDL (oxLDL), or malondialdehyde-derivatized LDL (MDA-LDL) as antigens. To monitor cross-reactivity of the antibodies detected with other oxidatively modified proteins, human serum albumin (HSA) and MDA-derivatized HSA (MDA-HSA) were also employed. The antibody titer was calculated as the ratio of antibodies against modified versus native proteins.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

[Magnetic resonance: preoperative assessment of abdominal aortic aneurysms. Comparison with surgical findings in 80 cases].

This work was aimed at assessing Magnetic Resonance (MR) accuracy in the preoperative investigation of abdominal aortic aneurysms, with a view to suggesting MRI as the method of choice for surgical planning, replacing other relatively invasive investigation techniques like angiography and enhanced CT. In the last 3 years 80 patients with abdominal aortic aneurysms identified with US or CT were examined with 0.5-T MRI and underwent surgical repair within 15 days. Spin-echo (SE) T1-weighted axial, sagittal and coronal sequences were always performed. In 18 patients gradient-echo (GE) flow sequences were also acquired; SE T2-weighted sequences were used to study parietal thrombi in 10 patients and finally Gd-DTPA T1-weighted sequences were obtained in inflammatory aneurysms (3 patients). MR images were blindly evaluated by 2 radiologists. The following variables which are useful for surgical planning were considered for each patient: aneurysm extent, characteristics of parietal thrombi, dissections, fixurations, inflammation signs, involvement of renal arteries, vena cava, ureters, duodenum, the presence of retroaortic renal vein or of other anomalies or associated conditions. MR images were always compared with intraoperative findings, since surgery was considered as the gold standard. MR findings were in agreement with surgical findings in the evaluation of cranio-caudal aneurysm extent (78/80), parietal thrombus features (80/80), dissection (1/1) and fixuration signs (8/9), origin of renal arteries (80/80), inferior vena cava involvement (3/3), other anatomical anomalies or conditions (6/6). Inflammation signs were overestimated (14/8) as well as adhesion between aneurysm and duodenum (17/13). The presence of distal renal polar arteries was underestimated (2/4). In conclusion, MRI proves to be a highly sensitive method to demonstrate abdominal aortic aneurysms and is therefore suggested as the examination of choice before surgery.

Adult↗