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X Aldeguer

Publications and source records attributed to X Aldeguer.

6 recordsLinked to original sources
PubMed2005

[Gastrointestinal inflammatory fibroid polyps. Clinical characteristics and follow-up in a series of 26 patients].

INTRODUCTION: Inflammatory fibroid polyp (IFP) is a protuberant lesion, located near the muscularis mucosae and composed of a proliferation of fusiform cells and conjunctive fibers surrounding capillaries and a variable inflammatory infiltrate. It is believed to be a poorly controlled inflammatory repair response. Our aim was to study the clinical, pathological and follow-up characteristics of a series of patients with IFP. PATIENTS AND METHOD: We studied 26 IFPs from 25 patients (16 women and 9 men) registered between 1985 and 2001 in a specific register of 3 centers in the city of Gerona (Spain). The variables analyzed were age, sex and clinical presentation, IFP localization and size, mucosal characteristics and associated disease, as well as follow-up information. Routine statistical analyses were performed. RESULTS: IFPs were antral in 16 patients, ileal in 7, jejunal in 2 and colonic in the remaining patient. Size determined whether they were symptomatic (35 +/- 13.6 mm) or asymptomatic (8.4 +/- 6.3 mm). Gastric polyps were significantly smaller than intestinal polyps. Symptomatic polyps (5 out of 16 gastric polyps and 9 out of 10 intestinal polyps) predominated in women and occurred at a significantly lower age than asymptomatic polyps (59.2 versus 74.1 years). Most gastric IFPs were associated with chronic atrophic gastritis while only one ileal polyp was associated with Meckels diverticulum. The mean length of follow-up was 60.6 months and, except in one patient who underwent incomplete resection, no recurrences of IFP were observed. CONCLUSION: IFP is a heterogeneous entity, depending on age at presentation, sex, size and location in the digestive tract. IFP does not recur after resection. The association of gastric IFP and chronic atrophic gastritis could suggest a modulatory effect of the mucosa on IFP growth.

Adult↗
PubMed2001

Modified AdCTLA-4 vector blocks alloimmune response in vitro.

BACKGROUND: Gene transfer of the costimulatory blockade molecule CTLA-4Ig into cold-preserved rat liver allografts results in indefinite allograft survival. Despite local delivery, this mode of immunomodulation is associated with systemic immunosuppression. In an effort to restrict immunosuppression to the graft, we have constructed a novel adenoviral vector, AdCTLA-4ex-TAG, in which the Ig sequence of CTLA-4Ig DNA has been deleted to destabilize the gene product to promote rapid extrahepatic degradation while maintaining its immunosuppressive activity within the graft milieu. METHODS: (1) Vector construction. CTLA-4 extracellular binding domain (CTLA-4ex) was prepared by PCR-based cloning methods and fused in frame to a genetic element encoding an epitope TAG allowing identification of the transgene product CTLA-4exTAG. CTLA-4exTAG was subcloned into a shuttle vector enabling isolation of AdCTLA-4exTAG. (2) In vitro transfection: AdCTLA-4exTAG was transfected into MH(1)C(1) cells and then supernatant was recovered for Western blot analysis. (3) In vitro alloimmune response was characterized by CFSE proliferation assay. (4) Extrahepatic effect of AdCTLA-4exTAG was characterized by the ability to control tumor growth after implantation of a regressive, immune sensitive cancer cell line (REGb) in the skin of BDIX rats after liver transduction with AdCTLA-4exTAG. RESULTS: Expression and secretion of the recombinant protein were documented by Western blot after infection of the MH(1)C(1) cell line() with AdCTLA-4exTAG. Addition of infected MH(1)C(1) cell supernatant resulted in abrogation of alloimmune response as shown by markedly diminished division of CD4(+) T cells in a CFSE proliferation assay. Extrahepatic tumor regressed normally after liver transduction with AdCTLA-4exTAG. CONCLUSIONS: These results show efficient in vitro expression of CTLA-4exTAG after transfection with AdCTLA-4exTAG. The modified protein retains its ability to abrogate in vitro alloimmune response. Efficient control of extrahepatic tumor growth after liver-directed delivery of AdCTLA-4exTAG suggests that the immunosuppressive effect of this vector is restricted to the liver. These results set the ground for the utilization of this novel adenoviral vector in the transplant setting.

Abatacept↗
PubMed2001

Activation of interleukin-6/STAT3 and liver regeneration following transplantation.

BACKGROUND: Every liver that is procured, stored, and transplanted experiences injury from cold ischemia and reperfusion. Most recover quickly, but some grafts sustain enough injury to result in prolonged organ dysfunction or require retransplantation. The molecular mechanisms involved in early graft function and recovery following cold ischemia and reperfusion (I/R) after liver transplantation have not been well defined. Interleukin (IL)-6 is a critical factor in the mitogenic response within the liver, and is important for cell cycle progression and protection from injury. Activation of the latent transcription factor, STAT3, is dependent on IL-6 release. The role of the IL-6/STAT3 pathway and hepatocellular regeneration in graft recovery and cell cycle progression following cold ischemia and reperfusion was studied in a rat liver transplant orthotopic (OLT) model. Methods. Rat OLT was performed in a syngeneic model. The presence, time course, and magnitude of expression of IL-6, STAT3 activation, and upregulation of target immediate early genes were determined in liver grafts with minimal (<1 h) and prolonged (12 h) cold preservation times followed by transplantation. Progression of the cell cycle and replication was confirmed by BrdU uptake. RESULTS: Prolonged cold ischemia resulted in increased IL-6 expression and STAT3 activation. This correlated with upregulation of junB, c-fos, c-myc, and c-jun, immediate early genes associated with hepatic regeneration. Extensive DNA replication was present in livers with 12-h ischemia, demonstrating successful completion of the cell cycle. CONCLUSIONS: The participation of the IL-6/STAT3 pathway leading to cell cycle progression and regeneration is an important component in the recovery of organs immediately following cold preservation and transplantation.

Animals↗
PubMed1999

Effect of intravenous albumin on renal impairment and mortality in patients with cirrhosis and spontaneous bacterial peritonitis.

BACKGROUND: In patients with cirrhosis and spontaneous bacterial peritonitis, renal function frequently becomes impaired. This impairment is probably related to a reduction in effective arterial blood volume and is associated with a high mortality rate. We conducted a study to determine whether plasma volume expansion with intravenous albumin prevents renal impairment and reduces mortality in these patients. METHODS: We randomly assigned 126 patients with cirrhosis and spontaneous bacterial peritonitis to treatment with intravenous cefotaxime (63 patients) or cefotaxime and intravenous albumin (63 patients). Cefotaxime was given daily in dosages that varied according to the serum creatinine level, and albumin was given at a dose of 1.5 g per kilogram of body weight at the time of diagnosis, followed by 1 g per kilogram on day 3. Renal impairment was defined as nonreversible deterioration of renal function during hospitalization. RESULTS: The infection resolved in 59 patients in the cefotaxime group (94 percent) and 62 in the cefotaxime-plus-albumin group (98 percent) (P=0.36). Renal impairment developed in 21 patients in the cefotaxime group (33 percent) and 6 in the cefotaxime-plus-albumin group (10 percent) (P=0.002). Eighteen patients (29 percent) in the cefotaxime group died in the hospital, as compared with 6 (10 percent) in the cefotaxime-plus-albumin group (P=0.01); at three months, the mortality rates were 41 percent (a total of 26 deaths) and 22 percent (a total of 14 deaths), respectively (P=0.03). Patients treated with cefotaxime had higher levels of plasma renin activity than those treated with cefotaxime and albumin; patients with renal impairment had the highest values. CONCLUSIONS: In patients with cirrhosis and spontaneous bacterial peritonitis, treatment with intravenous albumin in addition to an antibiotic reduces the incidence of renal impairment and death in comparison with treatment with an antibiotic alone.

Adult↗
PubMed1999

Serological markers and HLA-DQ2 haplotype among first-degree relatives of celiac patients. Catalonian Coeliac Disease Study Group.

Serologic markers, HLA-DQ2 haplotype, and clinical features suggestive of celiac disease were studied to assess their diagnostic value in a multicentric study to detect celiac disease in 675 first-degree relatives of 227 celiac probands. Serum IgA-class anti-endomysium and IgA-class anti-gliadin antibodies were positive in 5.8% and 1.9% of relatives, respectively. HLA-DQ2 haplotype was present in 64% of relatives, and the overall rate of celiac disease diagnosed by intestinal biopsy was 5.5%. The frequency of HLA-DQ2 in the celiac patients and controls was 93% and 18%, respectively. The most frequent clinical features--diarrhea, anemia, food intolerance, and growth retardation--were not present in one third of the celiac disease relatives. We conclude that the assessment of IgA-class anti-endomysium antibodies alone seems a reasonable approach for screening celiac disease in relatives and cannot be replaced by an accurate clinical anamnesis. HLA-DQ2 haplotype may identify the population with a high genetic susceptibility to celiac disease.

Adult↗