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L Cicalese

Publications and source records attributed to L Cicalese.

At least 19 recordsLinked to original sources
PubMed2001

Pyruvate inhibits hepatic ischemia-reperfusion injury in rats.

BACKGROUND: Ischemia/reperfusion (I/R) injury is a limiting factor in liver transplantation. We have recently shown that pyruvate (PY) inhibits intestinal and renal I/R injury. This study aims to evaluate the protective effect of PY on hepatic I/R injury. METHODS: ACI rats were treated with PY, whereas control animals received placebo. Rats were killed after 60 min of partial hepatic ischemia and after 2, 6, 24, and 48 hr of reperfusion. For each time point, serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase were measured, and liver biopsy specimens were obtained to evaluate morphology, DNA fragmentation, and apoptosis (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling). RESULTS: The survival rate 48 hr after I/R was 83% in the control group, and 100% in the PY-treated group (P>0.05). Increased enzymatic levels and histologic findings showed increased liver damage in the untreated group compared with PY. In control rats, apoptosis was enhanced after 1 hr of ischemia and peaked after 2 hr of reperfusion, to decrease gradually 48 hr after reperfusion; in the PY group apoptosis was delayed and reduced. After 1 hr of ischemia, the number of apoptotic nuclei was significantly increased in control livers compared with normal preischemic livers, whereas the number was significantly reduced by PY. After 2 hr of reperfusion, the maximum number of apoptotic cells was observed, whereas PY significantly reduced the amount of apoptotic cells (P<0.05). Apoptosis was delayed in PY-treated livers to 6 hr after reperfusion, peaking at a significantly lower count compared with placebo-treated controls (P<0.05). CONCLUSION: These data indicate that PY has a protective effect on I/R injury of the liver.

Animals↗
PubMed2001

Bacterial translocation in clinical intestinal transplantation.

BACKGROUND: Bacterial translocation (BT) has been suggested to be responsible for the high incidence of infections occurring after small bowel transplantation (SBTx). Bacterial overgrowth, alteration of the mucosal barrier function as a consequence of preservation injury or acute rejection (AR), and potent immunosuppression are all associated with BT. The aim of this study was to evaluate and quantify the correlation of BT with these events. METHODS: Fifty pediatric SBTx recipients on tacrolimus and prednisone immunosuppression were analyzed. Blood, stool, and liver biopsies and peritoneal fluid were cultured (circa 4000 total specimens) when infection was clinically suspected or as part of follow-up. BT episodes were considered when microorganisms were found simultaneously in blood or liver biopsy and stool. RESULTS: BT (average of 2.0 episodes/patient) was evident in 44% of patients and was most frequently caused by Enterococcus, Staphylococcus, Enterobacter, and Klebsiella. The presence of a colon allograft was associated with a higher rate of BT (75% vs. 33.3%). Furthermore, the transplantation procedure (colon vs. no colon) affected the rate of BT: SBTx=40% vs. 25%, combined liver and SBTx=100% vs. 30%, multivisceral transplantation=25% vs. 50%. AR was associated with 39% of BT episodes. BT followed AR in 9.6% of the cases. In 5.2% of the cases, positive blood cultures without stool confirmation of the bacteria were seen. Prolonged cold ischemia time (CIT) affected BT rate significantly (CIT>9 hr 76% vs. CIT<9 hr 20.8%). CONCLUSIONS: This study shows that 1) a substantial percentage of, but not all, BT is associated with AR, 2) the presence of a colon allograft increases the risk for BT, and 3) a long CIT is associated with a high incidence of BT after SBTx.

Acute Disease↗
PubMed2001

Risk factors for failure to meet listing requirements in liver transplant candidates with alcoholic cirrhosis.

BACKGROUND: The majority of liver transplant centers require a 6-month abstinence period before listing candidates for liver transplantation with alcoholic cirrhosis and a persistent sobriety thereafter. We attempted to identify risk factors for failure to comply with these requirements. METHODS: Ninety-nine consecutive patients with alcoholic cirrhosis were referred for liver transplant evaluation between September 1996 and May 1998. The mean age was 49 years, 74% were male, and 54% were hepatitis C virus positive. To be listed, patients had to meet the following requirements. All patients received extensive psychosocial evaluations and were frequently monitored with random urine and blood alcohol tests; patients found positive were excluded or removed from the liver transplant waiting list. Detailed patient information was entered into a computerized database, and 36 discreet variables were analyzed in relation to success (patient listed and remained on the list) or failure (not listed or removed from the list based on noncompliance). RESULTS: Forty-nine patients were successfully listed. Nineteen received a transplant, with a 95% 1-year patient and graft survival rate and 21% alcohol relapse rate after transplantation. Twenty-two patients had either medical contraindication and/or died before transplant listing. Twenty-four patients were never listed and four were removed from the list due to recurrent alcoholism, for a total of 28 failures. Our statistical analysis identified five significant risk factors for failure: (I) living arrangement (alone/family versus community/friend), P=0.006; (II) history of suicide ideation, P=0.03; (III) history of previous alcohol-related hospitalization, P=0.01; (IV) lack of previous alcoholic rehabilitation before transplant evaluation, P=0.001; and (V) failure to accept further alcoholic rehabilitation before orthotopic liver transplantation, P=0.01. CONCLUSIONS: Our experience confirms that transplantation can be extremely successful in properly selected patients with alcoholic cirrhosis. We identified several predictive psychosocial factors of early alcoholic recidivism in transplant candidates.

Contraindications↗
PubMed2001

Progressive functional adaptation of segmental bowel graft from living related donor.

We report a patient with short gut syndrome successfully treated with living related bowel transplantation. A 27-year-old Caucasian man was referred after traumatic loss of almost the entire bowel from the third portion of duodenum to the sigmoid colon. His HLA-identical sister volunteered as a donor. A 200-cm segment of ileum was successfully transplanted under tacrolimus-based immunosuppression. The posttransplant course was uneventful, without rejection or infectious complication. Total parenteral nutrition was discontinued 1 week posttransplant. At 6 months the patient had returned to his preinjury weight. Water and D-xylose absorption as well as fecal fat studies were markedly abnormal 1 month posttransplant but normalized by 6 months. The donor recovery was uneventful. A well-matched segmental ileal graft from living donor can provide complete rehabilitation for patients with short gut syndrome. We documented a progressive functional adaptation of the ileal graft, resulting in normal absorption by 5 months posttransplantation.

Adult↗
PubMed2001

Acute pancreatitis and bacterial translocation.

Infectious complications are the most frequent and severe complications of acute narcotizing pancreatitis (AP) with a mortality rate up to 80%. Although experimental and clinical studies suggest that the microbiologic source of pancreatic infection could be enteric, information in this regard is scant. This study evaluated bacterial translocation (BT) using mild and severe models of AP. Mild AP was induced by 6-hr continuous intravenous infusion of cerulein, while severe AP was induced by additional infusion of glycodeoxycholic acid into the biliopancreatic duct. BT was evaluated with organ cultures performed when animals were killed (24 hr). To confirm the gastrointestinal origin of the translocating microorganisms, fluorescent microspheres were also given to the animals in drinking water 24 hr before induction of AP. At the time of death beads were counted with a (fluorescence-activated cell sorter) (FACS) in peritoneal lavages and with fluorescent microscopy in frozen sections of the pancreata. Morphology of the distal small bowel showed significant changes in the animals with AP compared to controls, such as reduction of villus high and altered microvasculature. Mild AP induced BT to the pancreas in 100% of the animals, compared to pancreata from control groups. Severe AP induced increased BT to the pancreas. BT to liver and spleen was also significantly increased with AP. The presence of fluorescent microspheres confirmed their enteric derivation. This study provides evidence for the enteric origin of microorganisms responsible for pancreatic infectious complications during AP. The evidence of BT after laparotomy suggests an increased risk of infections with the association of these conditions. This could provide an explanation for the high mortality associated with laparotomy in course of AP.

Animals↗
PubMed2000

Intestinal microvascular patterns during hemorrhagic shock.

While injuries due to a hypoxic state commonly appear later in both intestinal crypts and basal portion of the villi than in the apical portion, a nonhomogeneous distribution of blood flow in the intestinal mucosa may be supposed. The presence of two different microvascular plexuses inside the mucosa, corresponding to the cryptal plexus and the villous plexus, supports the above hypothesis. This work studies the intestinal microvasculature in shocked versus normal rats. Forty-five rats were divided into four groups to study the histological damage and the microvascular bed by ink injection, fluorescent microsphere infusion, and resin injection for scanning electron microscopy (SEM) of vascular corrosion cast (VCC) observations. An infusion pressure of 100 +/- 5 mm Hg was used in control animals, while 30 +/- 5 mm Hg infusion pressure was adopted for controls as well as for shocked animals to simulate physiological or shock conditions. Hemorrhagic shock was induced by removing blood and maintaining a mean arterial pressure of 30 +/- 5 mm Hg for 45-120 mins. A close connection among the patterns of microvasculature obtained with VCC and ink injection technique can be appreciated. In normal rats the whole microvasculature was visualized, but in both normal and shocked animals injected at low pressure different patterns could be found, generally showing a highly incomplete visualization of the vascular network. A significant decrease of visualization of both the entire microvasculature and the villous plexus is present in shocked animals when compared to unshocked controls, while no difference in the cryptal plexus visualization was observed. These observations suggest that the cryptal plexus is perfused preferentially during hemorrhagic shock, as a consequence of its peculiar microvascular organization. This may explain the relative resistance of the crypts, compared to villi, to hypoxic injuries in order to sustain endocrine function and the regenerative capability of the mucosa after prolonged hypoperfusion conditions that can lead to villous damage and temporary loss of the intestinal barrier function.

Animals↗
PubMed2000

Low infectious complications in segmental living related small bowel transplantation in adults.

Clinical small bowel transplantation (SBTx) has been associated with a high rate of infectious complications. Laparotomy, preservation injury, abnormal motility, lymphatic disruption, aberrant systemic venous drainage, rejection and antibiotic therapy could all be implicated in the etiology of these complications. In addition to the underlying disease, total parental nutrition could determine infections and liver impairment. Recently, standardized techniques for segmental living related SBTx (LR-SBTx) have been developed. This technique allows reduction of some of these factors, thus resulting in a reduced incidence of infections. We report the infectious complications observed in 3 patients with short bowel syndrome treated with LR-SBTx at our institution. A segment of 180-200 cm of ileum was transplanted with a neglectably short cold ischemia time (CIT). The donor bowel was decontaminated. Oral tacrolimus, prednisone and IV induction with ATG were used for immunosuppression. Blood, stool, urine, sputum and peritoneal fluids were collected and cultured as a routine surveillance. All recipients are alive with a current follow-up time up to 21 months. No bacterial infections were observed during the post-transplant period. One patient developed cytomegalovirus (CMV) enteritis 4 months after LR-SBTx and was treated successfully with IV ganciclovir. In our limited experience, LR-SBTx is associated with a low infection rate. This could be due to optimal graft decontamination, short CIT and to the reduced incidence of rejection and lower immunosuppression used in this immunologically well-matched combination.

Adult↗
PubMed2000

[Transplantation of the intestines and bacterial translocation].

Infections, sepsis and multiple organ failure syndrome are associated with high morbidity and mortality in human and experimental small bowel transplantation (SBTx). These complications are attributed to bacterial translocation demonstrated in animal and human studies. Bacterial translocation (BT) is defined as the passage of viable bacteria from the intestinal lumen to other tissues or organs. BT has been associated with different clinical and experimental situations, hemorrhagic shock, trauma, bowel obstruction, immunodepression, total parenteral nutrition, antibiotics. Although BT has been investigated in several small and large animal models of SBTx, precise information on the mechanisms involved are not available. It is possible that the operative procedure by itself may promote BT for the interaction of a number of factors such as preservation, ischemia/reperfusion, abnormal motility, lymphatic disruption and aberrant systemic venous drainage, acute or chronic rejection and antibiotic therapy. Furthermore, the potent immunosuppressive therapy used in these patients may augment the deleterious effects caused by BT. In this review we examined the existing literature concerning BT with particular regard to intestinal transplantation, to better understand the alterations in the symbiotic relationship between immunocompromised host and his gut microflora after SBTx.

Animals↗