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J Visa

Publications and source records attributed to J Visa.

At least 19 recordsLinked to original sources
PubMed2005

One thousand liver transplants: the hospital clinic experience.

OBJECTIVES: Our goal was to study a consecutive series of 1000 liver transplants performed in our institution to evaluate the changes over time in donors, recipients, and results. PATIENTS AND METHODS: With the aim to evaluate differences between transplantation in the first period and the present period, the first consecutive 100 liver transplants performed from June 1988 to June 1990 (first period) were compared with the last consecutive 200 liver transplants performed from January 2001 to June 2003 (second period). RESULTS: Increased donor age, change in donor cerebral death etiology, and increasing numbers of grafts from alternative methods using cadaveric donors were observed in the second period. Piggy-back technique and the biliary anastomosis without a t-tube was also started in the second period. One-year actuarial patient survival was higher in the second period (84% vs 91.3%). The need for retransplantation in the overall series was 95%. One-, 5-, and 10-year actuarial retransplant survival was 67.7%, 51.3%, and 39.4%, respectively. CONCLUSIONS: Technical innovations, better understanding of donor and recipient aspects, and global improvements were the reasons for time-related improved results of liver transplantation.

Adult↗
PubMed2003

Risk factors for death following liver retransplantation.

AIM: Our goal was to retrospectively analyze graft loss and mortality risk factors using multi-centre data on liver retransplantation. MATERIAL AND METHODS: Between 1991-1995, 640 patients underwent 718 liver transplants in Barcelona. Mean age of the 74 patients receiving a second transplant was 47.6 years (range 19-65). Causes of retransplantation were immunologic in 26 patients (35.1%), technical in 23 (31.1%), primary dysfunction in 12 (16.2%), recurrent original disease in 7 (9.5%), and other causes in 6 (8.1%). Mean time between first and second transplant was less than 7 days in 20 patients (27%), between 8 and 30 days in 4 (5.4%) and more than 30 days in 50 patients (67.6%). Recipient, donor, and operative variables were analyzed using univariate (Kaplan-Meier curves) and multivariate techniques (Cox regression) to identify risk factors. RESULTS: Retransplant patient survival at 1 and 5 years was 60.8% and 49.5%, respectively, compared to 75.6% and 64.8% in a series of 640 first transplant patients. Mortality risk factors identified by multivariate analysis were bilirubin >12 mg/dL (RR 2.3; P=.010), recipient age (RR increase 0.04 for each additional year; P=.02), cause for retransplant (immunologic RR 4.01, technical RR 2.7 and other causes RR 6.9; compared to primary dysfunction RR 1; P=.020). Urea >54 mg/dL (0.02) and multiple transfusions >15 units red blood cells (0.001) were only significant in the univariate analysis. CONCLUSIONS: In our experience, retransplantation for primary dysfunction is the setting that has the best prognosis. Of the other causes, retransplantation should be performed before the total bilirubin reaches >12 mg/dL or before the appearance of variables indicative of severe renal insufficiency.

Adult↗
PubMed2001

Hand-assisted laparoscopic splenectomy (HALS) in cases of splenomegaly: a comparison analysis with conventional laparoscopic splenectomy.

BACKGROUND: Laparoscopic splenectomy (LS) is considerably more difficult to perform when the spleen is enlarged. The new technique of hand-assisted designed technique aimed to assist laparoscopic surgery allows the surgeon to insert his or her hand into the abdomen while maintaining the pneumoperitoneum, thus recovering the tactile sensation lost in conventional laparoscopic surgery. OBJECT: In this study, we compared the immediate results of conventional LS and hand-assisted LS (HALS) in cases of splenomegaly. METHODS: Between February 1993 and August 2001, 200 LS were attempted at two university hospitals. In 56 cases, splenomegaly (final spleen weight >700 g) was observed clinically or detected on radiological examination. We compared the first 36 patients operated on by conventional LS (group I) with the last consecutive 20 patients, who underwent HALS (group II). The study parameters were operative time, conversion rate, transfusion rate, morbidity and length of hospital stay. RESULTS: The groups were comparable in terms of age (58 +/- 13 [ranges, l9-82] vs 58 +/- 16 years [range, 44-84] (ns), diagnosis, and spleen weight (1425 +/- 884 [range, 700-3400]) vs 1753 +/- 1124 g [range, 720-4500] (ns). HALS was associated with less morbidity (36% vs 10%) (ns), a shorter operative time (177 +/- 52 [range, 95-300]) vs 135 +/- 53 min [range, 85-270] (p <0.009), and a shorter hospital stay (6.3 +/- 3.3 [range, 3-14]) vs 4 +/- 1.2 [range, 2-7] days (p <0.05). CONCLUSION: In cases of splenomegaly, HALS assisted laparoscopic surgery significantly facilitates the surgical maneuvers during LS while maintaining the advantages of a purely laparoscopic approach.

Adult↗
PubMed2001

Neurodevelopmental delay, motor abnormalities and cognitive deficits in transgenic mice overexpressing Dyrk1A (minibrain), a murine model of Down's syndrome.

Down's syndrome (DS) is a major cause of mental retardation, hypotonia and delayed development. Murine models of DS carrying large murine or human genomic fragments show motor alterations and memory deficits. The specific genes responsible for these phenotypic alterations have not yet been defined. DYRK1A, the human homolog of the Drosophila minibrain gene, maps to the DS critical region of human chromosome 21 and is overexpressed in DS fetal brain. DYRK1A encodes a serine-threonine kinase, probably involved in neuroblast proliferation. Mutant Drosophila minibrain flies have a reduction in both optic lobes and central brain, showing learning deficits and hypoactivity. We have generated transgenic mice (TgDyrk1A) overexpressing the full-length cDNA of Dyrk1A. TgDyrk1A mice exhibit delayed cranio-caudal maturation with functional consequences in neuromotor development. TgDyrk1A mice also show altered motor skill acquisition and hyperactivity, which is maintained to adulthood. In the Morris water maze, TgDyrk1A mice show a significant impairment in spatial learning and cognitive flexibility, indicative of hippocampal and prefrontal cortex dysfunction. In the more complex repeated reversal learning paradigm, this defect turned out to be specifically related to reference memory, whereas working memory was almost unimpaired. These alterations are comparable with those found in the partial trisomy chromosome 16 murine models of DS and suggest a causative role of DYRK1A in mental retardation and in motor anomalies of DS.

Animals↗
PubMed2001

Hepatic xanthine levels as viability predictor of livers procured from non-heart-beating donor pigs.

BACKGROUND: The aim of the present study was to evaluate hepatic content of adenine nucleotides and their degradation products in non-heart-beating donor (NHBD) pigs and its relationship with recipient survival. METHODS: Thirty animals were transplanted with an allograft from NHBDs. After warm ischemia (WI) time (20, 30, or 40 min), cardiopulmonary bypass and normothermic recirculation (NR) were run for 30 min. Afterward, the animals were cooled to 15 degrees C and liver procurement was performed. RESULTS: Survival rate was 100% in the 20WI, 70% in the 30WI, and 50% in the 40WI. Livers from non-surviving animals had higher levels of xanthine after NR than livers from surviving animals. Logistic regression analysis revealed that xanthine at the end of NR was the only variable able to predict survival with a calculated sensitivity of 80% and a specificity of 60%. Prolongation of warm ischemic period leaded to a greater xanthine accumulation as well as increased plasma alpha-glutathione S-transferase levels at reperfusion. Xanthine at NR and alpha-glutathione S-transferase at reperfusion significantly correlated, indicating that donor xanthine contributes to some extent to the severity of the lesion by ischemia-reperfusion. CONCLUSIONS: It is suggested that xanthine content in the donor is able to predict survival after transplantation. Xanthine is significantly involved in the hepatic lesion elicited by warm ischemia and subsequent ischemia-reperfusion associated to liver transplantation from a NHBD.

Animals↗
PubMed2001

Acute phase response in laparoscopic and open colectomy in colon cancer: randomized study.

PURPOSE: All types of trauma to the organism produce a systemic response that is proportional to the severity of the lesion caused. The more rapid clinical recovery during the postoperative period of patients undergoing laparoscopic-assisted colectomy vs. patients receiving conventional surgery suggests that laparoscopic surgery produces less surgical trauma. The aim of this randomized, prospective study was to compare acute phase postoperative response in patients diagnosed with colon neoplasm undergoing open segmentary colectomy vs. laparoscopic-assisted colectomy. METHODS: From June 1994 to July 1997 the results of 97 patients (58 submitted to open colectomy and 39 undergoing laparoscopic-assisted colectomy) were analyzed. Blood determinations of cortisol, prolactin, C-reactive protein and interleukin-6 were performed before surgery and at 4, 12, 24, and 72 hours after surgery. RESULTS: The plasma levels of cortisol and prolactin were higher in the postoperative period with both surgical techniques with no significant differences being observed. The levels of interleukin-6 achieved a maximum peak at 4 hours after surgery, later showing a decrease and practically achieving basal levels at 72 hours in both groups. The levels of interleukin-6 were higher with significant differences at 4, 12, and 24 hours in the patients undergoing open colectomy. The plasma levels of C-reactive protein were significantly lower at 72 hours in patients receiving laparoscopic-assisted colectomy. CONCLUSIONS: The results obtained in this randomized, prospective study suggest that acute phase systemic response is attenuated in patients undergoing laparoscopic-assisted colectomy in comparison with patients receiving open colectomy.

Acute-Phase Reaction↗
PubMed2001

Intrahepatic biliary lesions after orthotopic liver transplantation.

Intrahepatic biliary lesions (IBL) are rare (2-9%) after orthotopic liver transplantation (OLT). The aim was to evaluate the incidence, etiology and outcome. In nine years, a total 532 OLTs were performed in 481 patients. Twenty-four patients developed IBL. Eight were due to HAT, seven to ABOI, three to CDR and six to PI. The time until diagnosis of HAT is longest in patients (14+/-6) with IBL. ABOI is another cause of IBL. CDR is a rare cause of IBL, however when it takes place, patients must undergo Rtx. Finally, PI is a relevant cause of IBL. In order to suppress the incidence of IBL we should consider 1) the systematic use of Doppler-Ultrasound; 2) emergency reoperation of patients with HAT, 3) avoid ABOI in OLT; 4) Rtx in cases of CDR, and 5) OLT should still be performed as an emergency procedure.

ABO Blood-Group System↗
PubMed2001

Evaluation of risk of splenosis during laparoscopic splenectomy in rat model.

Laparoscopic splenectomy (LS) is an alternative to open surgery. However, there is a theoretic risk of splenosis and abdominal cavity dissemination of splenic cells if the splenic capsule is broken, as seen by experimental evidence of tumoral cell mobilization by the pneumoperitoneum. We evaluated the features of splenosis after splenectomy operated via an open approach or under laparoscopic control in an experimental model in the rat. A total of 65 Sprague-Dawley rats were distributed in seven groups that included the open approach, CO2 pneumoperitoneum LS, or wall lift LS with or without a splenic graft. Splenic function was evaluated 90 day later through (1) scintigraphy with Tc-labeled heat-damaged erythrocytes; (2) determination of circulating "pitted" cells; and (3) analysis of the distribution of splenic pulp in the peritoneal cavity. Scintigraphy did not show viable residual tissue in any group after splenectomy; splenic activity in the splenic fossa was observed in 40% of the animals with grafts. Splenectomy increased the "pit" cell count, but it was reduced to normal values with a splenic graft. Necropsy showed normal splenic tissue in the splenic fossa in 100% of animals with a graft. Abdominal implants were observed significantly more frequent after CO2 LS than after the open surgery or a wall lift LS (80% vs. 20% vs. 30%; p < 0.05). In addition, trocar site implants were observed with CO2 LS (n = 3) or wall lift LS (n = 2), whereas there were no implants in the wound in the open group. We conclude that in an experimental rat model the pneumoperitoneum may facilitate abdominal splenosis after LS if the splenic capsule is ruptured or if splenic tissue spills compared with surgery without gas (open or laparoscopic).

Abdominal Muscles↗
PubMed2001

Hepatopulmonary syndrome in candidates for liver transplantation.

BACKGROUND: Hepatopulmonary syndrome (HPS) has been defined as a clinical triad, including chronic liver disease, gas exchange defects (increased alveolar-arterial PO2 difference irrespective of the presence of arterial hypoxemia), and widespread intrapulmonary vascular dilatations. We determined the incidence and the clinical and pulmonary functional characteristics of HPS in candidates for orthotopic liver transplantation (OLT) and tested their predicted accuracy. METHODS: We studied 80 patients with cirrhosis prospectively, and carried out contrast-enhanced (CE) echocardiography and lung function tests, including ventilation-perfusion (V(A)/Q) distributions. RESULTS: Fourteen patients had HPS (incidence, 17.5%). Patients with HPS (49 +/- 12 (+/-SD) years) had more cutaneous spiders, finger clubbing and dyspnea (P < 0.05 each) and a lower diffusing capacity (DLCO, 56 +/- 18% predicted; P < 0.001) than non-HPS patients (n = 66). Mild to moderate V(A)/Q inequalities and increased intrapulmonary shunt were predominant in HPS patients, but oxygen diffusion impairment was observed in those with hypoxemia (n = 8) only. The DLCO showed a considerable area under the receiver operating characteristic curve (0.89). CONCLUSIONS: HPS in cirrhotic patient candidates for OLT shows a high incidence and these patients present with distinctive clinical and functional features compared with non-HPS individuals. The presence of a low DLCO may be of help for the diagnosis of HPS.

Adult↗
PubMed2001

Gamma-detecting probe used intraoperatively to locate the sentinel lymph node in patients with malignant melanoma.

OBJECTIVE: To assess the usefulness of lymphoscintigraphy and intraoperative gamma probe in the detection of sentinel lymph nodes. DESIGN: Prospective open study. SETTING: University hospital, Spain. SUBJECTS: 40 patients with malignant melanoma (24 stage I/II, 16 stage III). INTERVENTION: The day before operation a lymphoscintigram with 99mTc-nanocolloid was taken and the first lymph node identified was considered to be the sentinel node. A hand-held gamma probe was used for intraoperative mapping. MAIN OUTCOME MEASURE: Identification of the sentinel node. RESULTS: Sentinel nodes were identified in 39/40 patients (98%). In 24 patients with stage I/II disease, 34 sentinel nodes were found (6 invaded and 28 clear of melanoma). A total number of 161 regional lymph nodes were harvested, none of them invaded by melanoma. In 16 patients with stage III disease, 22 sentinel nodes were located (14 invaded and 8 clear of melanoma). A total of 89 regional lymph nodes were excised in patients with invaded sentinel nodes (44 of which were invaded and 45 clear of disease). 41 lymph nodes were excised from patients with clear sentinel nodes, and all were also clear of melanoma. CONCLUSIONS: We conclude that this is a useful technique for the selection of patients with melanoma who may require lymphadenectomy.

Adult↗
PubMed2000

Laparoscopic management of Spigelian hernia.

Spigelian hernia (SH) is an uncommon abdominal wall hernia. Its clinical symptoms are not characteristic, and the preoperative diagnosis is often difficult because SH can simulate the symptoms of more classical lower quadrant abdominal diseases. We report a case of SH in an 80-year-old woman that was complicated by incarceration and diagnosed by physical examination and ultrasound. At the time of presentation, she had an abdominal mass that was soft and occasionally painful, and aggravated by movements that increase intraabdominal pressure. Laparoscopic examination of the abdominal cavity identified the incarcerate jejunum ansae. The defect was a large opening in the peritoneum along the lateral margin of the rectus abdominis muscle. After dissection of the intestinal adhesions, a prosthetic polypropylene mesh was introduced and fixed with staples into the lateral abdominal wall. There were no postoperative complications. We conclude that the laparoscopic approach is a feasible alternative to the conventional open technique that is easy, safe, and allows excellent operative visualization.

Abdominal Muscles↗
PubMed2000

L-arginine reduces liver and biliary tract damage after liver transplantation from non-heart-beating donor pigs.

BACKGROUND: To evaluate whether L-arginine reduces liver and biliary tract damage after transplantation from non heart-beating donor pigs. METHODS: Twenty-five animals received an allograft from non-heart-beating donors. After 40 min of cardiac arrest, normothermic recirculation was run for 30 min. The animals were randomly treated with L-arginine (400 mg x kg(-1) during normothermic recirculation) or saline (control group). Then, the animals were cooled and their livers were transplanted after 6 hr of cold ischemia. The animals were killed on the 5th day, liver damage was assessed on wedged liver biopsies by a semiquantitative analysis and by morphometric analysis of the necrotic areas, and biliary tract damage by histological examination of the explanted liver. RESULTS: Seventeen animals survived the study period. The histological parameters assessed (sinusoidal congestion and dilatation, sinusoidal infiltration by polymorphonuclear cells and lymphocytes, endothelitis, dissociation of liver cell plates, and centrilobular necrosis) were significantly worse in the control group. The necrotic area affected 15.9 +/- 14.5% of the liver biopsies in the control group and 3.7 +/- 3.1% in the L-arginine group (P<0.05). Six of eight animal in the control group and only one of eight survivors in the L-arginine group developed ischemic cholangitis (P<0.01). L-Arginine administration was associated with higher portal blood flow (676.9 +/- 149.46 vs. 475.2 +/- 205.6 ml x min x m(-2); P<0.05), higher hepatic hialuronic acid extraction at normothermic recirculation (38.8 +/- 53.7% vs. -4.2 +/- 18.2%; P<0.05) and after reperfusion (28.6 +/- 55.5% vs. -10.9 +/- 15.5%; P<0.05) and lower levels of alpha-glutation-S-transferase at reperfusion (1325 +/- 1098% respect to baseline vs. 6488 +/- 5612%; P<0.02). CONCLUSIONS: L-Arginine administration during liver procurement from non heart beating donors prevents liver and biliary tract damage.

Animals↗
PubMed2000

Could age be an indication for laparoscopic colectomy in colorectal cancer?

BACKGROUND: The incidence of colorectal carcinoma increases in the elderly. Regardless of age as an isolated factor, postoperative complications represent the main factor in increasing hospital mortality. METHODS: The aim of this study was to compare the short-term results (first 30 postoperative days) after laparoscopically assisted colectomy (LAC) and open segmental colectomy (OC) in colorectal carcinoma between two groups of patients, older than 70 and younger than 70 years of age. In the study from November 1993 to June 1998, 255 patients were evaluated to participate. RESULTS: Peristalsis, oral intake, and discharge from the hospital occurred earlier in LAC than in OC treated patients, in the two age groups. The mean operative time was significantly longer in the LAC than in the OC patients in the two age groups. No differences were observed in morbidity between LAC and OC in the group younger than 70 years of age. However, the overall morbidity was significantly lower in the LAC group in patients older than 70 years. One patient in the LAC group older than 70 years died. CONCLUSION: These results suggest that laparoscopically assisted colectomy may be particularly indicated in elderly patients.

Age Factors↗
PubMed2000

Transgenic mice overexpressing insulin-like growth factor-II in beta cells develop type 2 diabetes.

During embryonic development, insulin-like growth factor-II (IGF-II) participates in the regulation of islet growth and differentiation. We generated transgenic mice (C57BL6/SJL) expressing IGF-II in beta cells under control of the rat Insulin I promoter in order to study the role of islet hyperplasia and hyperinsulinemia in the development of type 2 diabetes. In contrast to islets from control mice, islets from transgenic mice displayed high levels of IGF-II mRNA and protein. Pancreases from transgenic mice showed an increase in beta-cell mass (about 3-fold) and in insulin mRNA levels. However, the organization of cells within transgenic islets was disrupted, with glucagon-producing cells randomly distributed throughout the core. We also observed enhanced glucose-stimulated insulin secretion and glucose utilization in islets from transgenic mice. These mice displayed hyperinsulinemia, mild hyperglycemia, and altered glucose and insulin tolerance tests, and about 30% of these animals developed overt diabetes when fed a high-fat diet. Furthermore, transgenic mice obtained from the N1 backcross to C57KsJ mice showed high islet hyperplasia and insulin resistance, but they also developed fatty liver and obesity. These results indicate that local overexpression of IGF-II in islets might lead to type 2 diabetes and that islet hyperplasia and hypersecretion of insulin might occur early in the pathogenesis of this disease.

Animals↗
PubMed1999

E.A.E.S. multicenter prospective randomized trial comparing two-stage vs single-stage management of patients with gallstone disease and ductal calculi.

BACKGROUND: The current management of patients with gallstone disease and ductal calculi consists of endoscopic stone extraction (ESE) followed by laparoscopic cholecystectomy (LC). Following the advent of techniques of laparoscopic ductal stone clearance, an alternative single-stage laparoscopic treatment was introduced for these patients. The European Association of Endoscopic Surgery (E.A. E.S.) set up a ductal stone trial to compare the relative efficacy and outcome of these two management options. METHODS: A prospective randomized controlled clinical trial compared two management options. Group A (n = 150) received preoperative endoscopic retrograde cholangiography (ERC) with ESE followed by LC during the same hospital admission, and group B (n = 150) received single-stage laparoscopic management. RESULTS: There were no significant differences between the two groups in the clinical demographic details and the pretreatment biochemical findings. In group A, 14 of 150 patients received single-stage treatment; in group B, 17 of 150 were managed by the two-stage approach (protocol violation = 31/300, 10%). In group A patients managed in accordance with randomization, ERC was successful in 129/136 (95%) and preoperative ESE succeeded in 82/98 (84%) with ductal calculi detected by the ERC. Two patients had malignancies and one refused surgery. Thus, 133 patients underwent surgery. Of this group, 116 had LC only and 17 had LC and attempted laparoscopic duct exploration. There were eight conversions to open surgery (6%), 17 complications for both stages (12.8%), and two postoperative deaths (1.5%). In group B patients managed in accordance with randomization, intraoperative cholangiography was successful in 132/133 (99%). Twenty-one (16%) had normal findings, ductal calculi were found in 109, and other pathology was noted in two (periampullary cancer, severe pancreatitis). These two patients and one other (who had gross adhesion in the triangle of Calot) were converted at the start of the procedure. Transcystic ductal stone clearance was successful in 45 of 56 patients (80%), and laparoscopic direct common duct (CBD) exploration was successful in 47 of 55 patients (85%). This group includes 53 patients who underwent primary direct exploration and two failed attempts at transcystic extraction. The conversion rate was 13%. Postoperative complications were encountered in 21 patients (15.8%), and one patient died of a major myocardial infarction (0. 75%). The one postoperative death and the 10/11 biliary complications occurred in the laparoscopic supraduodenal CBD exploration subgroup. The conversion rate was higher in group B (17 vs eight; p = 0.08). Laparotomy in the postoperative period was required in three patients in group A and four patients in group B. The group B patients were in hospital for 3 days less than patients who had two-stage management (median, 6.0, IQR = 4.25-12 vs median, 9.0, IQR = 5.5-14; p < 0.05). CONCLUSIONS: The results demonstrate equivalent success rates and patient morbidity for the two management options but a significantly shorter hospital stay with the single-stage laparoscopic treatment. The findings indicate that in fit patients (ASA I and II), single-stage laparoscopic treatment is the better option, and preoperative ESE should be confined to poor-risk patients-i.e., those with cholangitis or severe pancreatitis.

Adolescent↗