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Biomedical subjects

U Valente

Publications and source records attributed to U Valente.

At least 127 records · Page 7Linked to original sources

Innovative strategies to expand cadaveric donor pool for liver transplantation (SITF project): a network between Italian transplantation centers supported by the Ministry of Health.

In 2002, the Italian Ministry of Health (IMH) launched a formal call for health research programs within the Research and Development (R&D) Policy. In this context, the research program "Innovative Strategies to Expand Cadaveric Donor Pool for Liver Transplantation" (SITF Project) has been proposed. The SITF Project has been formally approved by IMH as a 2-year research program included in the R&D Policy. The main goals of the SITF Project are to improve matching criteria for split liver transplantation (SLT) in both pediatric and adult recipients, to promote an increase of the SLT/full- size liver transplantation ratio at the national level, and, especially, to establish shared criteria for SLT in 2 adult recipients. The original executive plan of the SITF Project prefigured the participation of both the Italian transplantation centers with more advanced experience in the field of SLT, and institutional partnership, such as Nord Italia Transplant (NITp) and Italian National Transplant Center. A first Web public area concerning the SITF Project has been activated, as well as a reserved Web area with the aim to share cadaveric donors and patients in the waiting lists between Operative Units involved in the research program. For this objective, the first version Oracle-based database able to perform an automatic matching between a single cadaveric donor and 2 potential adult recipients has been released at the beginning of 2005. The SITF Project represents a new approach in the management of SLT for 2 adult recipients in Italy and a model for a functional network between Italian transplantation centers.

Cadaver↗

Impact of different cadaveric donor age cut-offs on adult recipient survival after liver transplantation: a single-center analysis.

The increase in the number of patients awaiting liver transplantation (OLT) has forced the use of cadaveric donors (CD) with suboptimal characteristics. Of these, donor age is perhaps the most investigated parameter. Although excellent outcomes were observed for OLT using CD aged over 60 years, the European Liver Transplant Registry (ELTR) Group found an increased risk by using CD of more than 55 years. The Italian National Transplant Center has recently assumed that CD age more than 60 years is a potential risk factor for OLT. In this study, a single-center analysis was performed by stratifying CD by three age cut-offs (< or =55 or >55, < or =60 or >60, and < or =65 or >65 years) to evaluate effects on OLT outcome. Although no significant difference in 6-month and 1-year patient or graft survival occurred after stratification for each donor age cut-off, a better survival was observed with OLT performed using livers procured from CD >55 years. A significant increase in cold ischemia time (CIT) was observed among OLT performed with grafts procured from CD < or =55 and < or =65 years (P = .007), and there was an inverse correlation between overall CIT and donor age (R = -0.300; P = .0022). However, no impact on 1-year patient survival was observed by introducing CIT in univariate logistic regression models as well as donor age, recipient age, donor/recipient age ratio, donor/recipient sex mismatch, ELTR diagnostic categories, and UNOS status. The results of this study suggest the suitability of CD of more than 55 years for OLT and the need to further investigate the cut-off value for CIT-related risk.

Adolescent↗

Cytotoxic molecule mRNA expression in chronically rejected human kidney allografts.

The pathogenesis of immunological and nonimmunological components that cause chronic kidney allograft nephropathy (CAN), is not yet completely understood. To explore the possible contribution of alloreactive cytotoxic T cells, we analyzed the transcription of cytotoxic molecules such as granzyme B and perforin using semiquantitative RT-PCR on surgically removed grafts obtained from two groups: group 1 (n = 10) were cases of CAN; group 2 (n = 3) had no CAN. Among group 1 kidneys, granzyme-B was expressed in 7 of 10, whereas perforin was detectable in 9 of 10 cases; their detection was not related to the presence of superimposed signs of acute graft lesions. Cytotoxic molecules were never found in group 2 kidneys. These results show that explanted chronically rejected grafts display cytotoxic molecule transcripts in addition to Th2 type cytokines, such as IL-10, IL-3, and IL-6, suggesting that both cellular and humoral alloreactive mechanisms may play important roles in CAN pathogenesis.

Antigens, CD↗

Dopamine "renal dose" versus fenoldopam mesylate to prevent ischemia-reperfusion injury in renal transplantation.

Low dose of dopamine is commonly used after kidney transplantation as a reno-protective agent, although its benefits are controversial. Dopamine may increase renal blood flow, decrease resistive index (RI), and induce urine output in normal kidneys. Many authors hypothesized that the vasculature of a denervated renal transplant may not respond to dopamine in the same fashion as healthy native kidneys, which led us to find other drugs to attenuate the ischemia-reperfusion (I/R) injury. Fenoldopam is a selective dopamine1 (DA1) receptor agonist, most of the activity of which resides in the R-enantiomer, which also shows weaker alpha 2-adrenoceptor antagonist activities. Fenoldopam produces a vasidilatory effect in vascular beds that are rich in vascular DA1 receptors, producing increased renal blood flow at doses that do not affect blood pressure. In addition to its renal vasodilator activity, fenoldopam is natriuretic, possibly resulting from a direct effect of DA1 receptors on the proximal convoluted tubule. In animals with spontaneous or drug-induced renal failure, fenoldopam improves renal function. The aim of this study was to investigate the possible effects of fenoldopan mesylate in recent kidney transplants. Creatinine, blood urea nitrogen, urine output, and renal vascular resistive index (IR) were measured using Doppler ultrasound. Two groups of patients with no statistical differences in demographic data were treated with dopamine or fenoldopan, showing no significant difference but a trend favoring the fenoldopan group.

Adult↗

Tauroursodeoxycholic acid administration as adjuvant therapy in cirrhotic patients on transplantation waiting lists.

BACKGROUND/AIMS: The lack of organ availability and an increased number of end-stage cirrhotic patients has led to the lengthening of liver transplantation waiting lists. The progressive worsening of clinical and functional performance in patients awaiting the graft is one of the factors implicated in the increased mortality during the wait and in poor transplantation outcome. In this work our aim was to evaluate the effects of tauroursodeoxycholic acid administration on biochemical, clinical and functional parameters in a group of cirrhotic patients consecutively placed onto our liver transplantation waiting list. METHODOLOGY: Ten cirrhotic patients underwent biochemical, clinical and functional evaluation at the time of entering on our liver transplantation waiting list, then tauroursodeoxycholic acid was administered until liver transplantation. Complete evaluation was repeated every 2 months. The results were compared to those of a comparable historical control group that had undergone liver transplantation the year before the study. RESULTS: All patients were transplanted within 6 months from insertion on the waiting list. Longitudinal analysis of the treated group showed that cholestasis and cytolisis parameters constantly decreased and that gamma-glutamyl transpeptidase was significantly lower compared to baseline values at the 4th month of therapy. Clinical and functional parameters remained stable during follow-up. Comparison with the control group showed that gamma-glutamyl transpeptidase, alkaline phosphatase and both aminotransferases were reduced at the 4th month of therapy. Fewer days of hospital stay and less intensive care were required in the treated group. CONCLUSIONS: Treatment of end-stage cirrhotic patients awaiting liver transplantation with tauroursodeoxycholic acid improves biochemical parameters of cytolisis and cholestasis, and furthermore helps to maintain clinical and functional stability during the wait. Improved biochemical conditions and steady clinical-functional performance may promote better short-term transplant outcome.

Case-Control Studies↗

Orthotopic liver transplantation in a young adult (33 years old) using an 84-year-old donor.

Shortage of liver donors and the increasing number of patients on the waiting list for liver transplantation have led to a widening of the definition of liver donor suitability. Although the age limit for liver donors is controversial, current opinion is towards using liver allografts from donors older than 60 years. However, to date only a few cases that showed a good performance of liver graft by donors older than 60 years have been described. In this case report, orthotopic liver transplantation in a 33-year-old patient who received a graft from an 84-year-old donor is presented. A careful evaluation of the conventional donor-related risk factors (hemodynamics, hepatic function and histologic features) was carried out. Moreover, free radical scavenger glutathione was measured before cold ischemia and at the time of reperfusion in hepatic biopsies. After a 1-year follow-up, the recipient exhibits good general conditions and normal liver function values.

Adult↗

[Extensive resections in rectal carcinoma. Our experiences].

The authors review their experience in the surgical management of rectal cancer. They analyze rectal malignancies and their recurrences from natural history to surgical strategies and survival rates. In particular, the need to perform extended operations in order to offer patients a better prognosis is discussed.

Adult↗

[Cystic lymphangioma of the adult: our experience and review of literature].

Cystic lymphangioma is an uncommon benign pathology, usually reported in children, rarely in adult. Its embryopathogenesis is still controversial: it seems to arise from the lymphatic vessels, mainly in the cervico-cranial district. It is macroscopically characterised by multiple cystic non-communicating concamerations. Definitive diagnosis used to be intraoperative and was usually an unexpected finding. Nowadays, with modern imaging technologies, CT and MRI, diagnosis can be assumed before intervention even though certain diagnosis can still be reached only with histological examination. Imaging techniques can help for a precise mapping of the lesion and definition of its limits with the other structures, improving therapeutic success. Various therapeutical options are reported in literature, but complete surgical excision is still considered the best approach and the most successful. The Authors report their experience and review the literature on cystic lymphangioma in adult.

Adult↗

[Total splenectomy for a recurrent giant splenic cyst].

Primary splenic cysts are a rare finding. Some are large and require surgical removal. The Authors report a case of a recurrent huge splenic cyst in a 41-year-old female patient. A marsupialization was performed at another hospital 6 years before. Ultrasonography and computed tomography imaging revealed a cystic lesion in the spleen measuring approximately 20 cm in diameter. A total open splenectomy was performed. Postoperative course was uneventful. The histologic diagnosis was an epithelial cyst of the spleen with no atypical cells in the cyst wall, as previously found at the first operation. The epidermoid cysts have an epidermal lining, and prevention of recurrence is dependent on complete resection of the cyst wall preserving, whenever possible, the splenic tissue. Recurrence can be avoided with partial splenectomy in polar localization of the cyst, or complete removal of the cyst by "peeling" it off the splenic parenchyma. Marsupialization of the cyst, either via a laparoscopic or an open approach, is often ineffective.

Adult↗