Search PubMed⌕ Search

Biomedical subjects

A Segarra

Publications and source records attributed to A Segarra.

At least 19 recordsLinked to original sources
PubMed2003

Outcome of 28 split liver grafts.

UNLABELLED: Our aim is to present our experience with split liver transplantation. From 1992-2002, 14 livers were split to obtain 28 grafts that were transplanted to 12 adults and 16 children. Ex situ splitting was performed in all cases. The left graft consisted of the left lateral segment (segments II-III) in 11 cases and the left lobe in three, depending on the size of the pediatric recipient. Pediatric recipients were of mean age 3, 4 years; mean weight 13 kg; six emergency cases for fulminant hepatic failure or urgent retransplantation and seven of 10 elective cases for biliary atresia. Postoperative mortality rate was 31% (five cases), including four of six emergency cases and one elective case (10%). The main cause was multiorgan failure. Technical complications were: one arterial thrombosis, one portal vein thrombosis, and four biliary complications. Eleven patients are alive and well. Adult recipients were of mean age 53 years. The indications were hepatocellular carcinoma in six cases, liver cirrhosis of various etiologies in five, and one recurrence of hepatitis C in a graft. Two patients died during the postoperative period from sepsis after retransplantation for primary nonfunction of the split graft and multiorgan failure with sepsis. One-year actuarial survival was 84%. CONCLUSIONS: The results of split liver transplantation in elective cases are similar to whole liver transplantation, whereas patient survival among emergency cases is low due to the critical condition of the patients.

Adult↗
PubMed2003

Predictors of poor renal outcome in patients with lupus nephritis treated with combined pulses of cyclophosphamide and methylprednisolone.

Lupus nephritis remains a major cause of morbidity and mortality in patients with systemic lupus erythematosus. Although the renal prognosis has improved, the optimal therapeutic regime has not been definitively established, and significant challenges remain in the management of disease progression and recurrent renal relapse. We performed a prospective study to evaluate the outcome of 38 patients with severe lupus nephritis treated with standard cyclophosphamide and methylprednisolone pulse therapy, and to determine the variables associated with poor outcome. Five patients developed end-stage renal disease (ESRD) (13%), 10 (26%) developed persistent proteinuria (> 1 g/24h) and 15 (39%) suffered at least one relapse after 8 years of follow-up. A high chronicity index, interstitial fibrosis (P = 0.04), persistent hypertension (P < 0.0001) and hypocomplementaemia (P = 0.002) after treatment were the major variables associated with ESRD. Tubular atrophy (P = 0.01), persistent hypertension (P = 0.0001) and hypocomplementaemia after treatment (P = 0.0281) were associated with persistent proteinuria. Persistence of anti-dsDNA antibodies and hypocomplementaemia after treatment (P = 0.0118) were associated with renal relapse. Our data suggest that the group of patients with persistence of hypocomplementaemia and raised anti-dsDNA antibodies titres are at high risk of renal relapse and may be candidates for continuation of immunosuppressive treatment. Patients with persistent proteinuria alone or a high chronicity index are less likely to respond to immunosuppression, and strict control of the hypertension may be the best approach.

Adolescent↗
PubMed2001

Early imaging of integration response to polypropylene mesh in abdominal wall by environmental scanning electron microscopy: comparison of two placement techniques and correlation with tensiometric studies.

The repair of incisional hernias has taken advantage of the strength provided by prosthetic mesh grafts, but the best position for inserting the materials has not been conclusively established. Environmental scanning electron microscopy (ESEM) provides imaging of biologic samples with minimal manipulation. We used ESEM for early imaging of the integration response to polypropylene meshes placed in two anatomic positions in the abdominal wall and correlated results with tensiometric studies. Two macroporous polypropylene prostheses were implanted in a rat model--one on the abdominal aponeurotic layer and one on the peritoneal surface--without creating a wall defect. Studies were performed over implantation intervals of 7, 15, and 30 days in strips obtained from the polypropylene fiber-receptor repair tissue interface. Microscopic appearance, tensile strength, percent elongation, and stiffness were evaluated. Meshes implanted on the abdominal aponeurotic layer showed better early tissue incorporation (higher collagen deposition, capillary density, cell accumulation) and increased tensile strength, reflecting tighter anchorage to the abdominal wall. The percent elongation increased from day 7 to day 30 after implantation, mainly in the deep stratum. The ESEM images correlated well with biomechanical results, indicating the potential of this technique as a powerful, effective tool for use in wound-healing studies.

Abdominal Muscles↗
PubMed2001

Hemoperitoneum as a first manifestation of hepatocellular carcinoma in western patients with liver cirrhosis: effectiveness of emergency treatment with transcatheter arterial embolization.

Hemoperitoneum is a well-known form of hepatocellular carcinoma presentation and represents a frequent complication in countries with a high incidence of hepatocellular carcinoma, but it is rarely seen in Western countries. Our aim was to report the results and describe the arteriographic and CT-scan characteristics in a series of seven consecutive patients. They were admitted to our hospital because of hemoperitoneum due to ruptured tumor as a first manifestation of hepatocellular carcinoma, and the rupture was effectively controlled by transcatheter arterial embolization. From April 1989 to April 1998, 440 consecutive patients were admitted to our liver unit with the diagnosis of hepatocellular carcinoma and liver cirrhosis. Fourteen patients (3%) presented with acute hemoperitoneum due to tumor rupture as a first manifestation of hepatocellular carcinoma. We here report our experience in the group of patients treated by transcatheter arterial embolization. Mean age was 67.1+/-5 years (range, 61-73). All patients presented with sudden abdominal pain, abdominal distension, and four patients had symptoms of acute anemia. In all cases the ruptured tumor was subcapsular. The procedure was effective in the control of bleeding in all cases, without significant impairment in liver function or treatment-related deaths. In six of the seven patients, a self-limited postembolization syndrome was observed. Mean survival time was 273+/-488.7 days (range: 15-1290). Three patients survived more than six months but at the time of evaluation, only one patient was alive. In conclusion, the present results confirm that transcatheter arterial embolization is an effective and well-tolerated treatment in the management of hemoperitoneum due to ruptured hepatocellular carcinoma in patients with liver cirrhosis.

Aged↗
PubMed2001

Expression of the HIV-1 co-receptors CCR5 and CXCR4 on placental macrophages and the effect of IL-10 on their expression.

The chemokine receptors CCR5 and CXCR4 play a key role in HIV-1 infection as co-receptors for viral entry. In the placenta, an important natural barrier to HIV, the expression and regulation of these receptors has yet to be elucidated. In this study, we determined the expression of CCR5 and CXCR4 co-receptors on placental macrophages (PM) and the effect of interleukin-10 (IL-10) on co-receptor expression. PM were isolated from term placentae of HIV-uninfected mothers and cultured for up to 11 days. The cells were stimulated with IL-10 for 24 h and stained with specific antibodies to CCR5, CXCR4, CD4, CD3, CD11c and CD14 for flow cytometry. Unstimulated PM expressed significantly more CCR5 than CXCR4. Expression of both co-receptors was upregulated by stimulation with IL-10 at 24 h post-stimulation. In vivo expression of these co-receptors from frozen sections revealed a higher percentage of CCR5 positive cells. This is the first study in which expression of both co-receptors is detected on the PM membrane. These results are consistent with previous studies performed in our laboratory where PM were readily infected by CCR5-using HIV strains but could not be productively infected by HIV strains that exclusively use CXCR4 as a co-receptor.

Acquired Immunodeficiency Syndrome↗
PubMed2001

Outcome and hepatic hemodynamics in liver transplant patients with portal vein arterialization.

UNLABELLED: Few cases of successful portal vein arterialization in orthotopic and auxiliary liver transplantation have been reported. AIM: To evaluate the effect of portal vein arterialization on hepatic hemodynamics and long-term clinical outcome in three patients undergoing liver transplantation. METHODS: Two patients with extensive splanchnic venous thrombosis received an orthotopic liver transplant and one with fulminant hepatic failure received an auxiliary heterotopic graft. Portal vein arterialization was performed in all cases. RESULTS: One patient died 4 months after transplant and two are still alive. Auxiliary liver graft was removed 3 months post-transplant when complete native liver regeneration was achieved. Immediate post-transplant liver function was excellent in all cases. Only one patient developed encephalopathy and variceal bleeding owing to prehepatic portal hypertension secondary to arterioportal fistula 14 months after transplant. He was successfully treated by embolization of the hepatic artery. Hepatic hemodynamic measurements demonstrated a normal pressure gradient between wedged and free hepatic venous pressures in all cases. Liver biopsy showed acceptable graft architecture in two cases and microsteatosis in one. CONCLUSIONS: Liver transplantation with portal vein arterialization is an acceptable salvage alternative when insufficient portal venous flow to the graft is present. The double arterial supply does not imply changes in hepatic hemodynamics, at least in the early months post-transplant.

Adult↗
PubMed2000

Early effects of exogenous arginine after the implantation of prosthetic material into the rat abdominal wall.

We have investigated the effects of high arginine (Arg) levels (7.5 mg/100 g body weight per hour) on the early integration of biocompatible mesh grafts into the rat abdominal wall. Studies were performed over implantation intervals of 6, 12, 24 or 48 hours (n=12, each). Arginine and related compounds were quantified in plasma, wound fluids and multiple tissues. Plasma nitric oxide (NO) production was studied. Strips were taken from the polypropylene fiber-host tissue interfaces (PTIs) for optical microscopic analysis and for immunohistochemical analysis using rat-specific antibodies against type I and type III collagens. Exogenous Arg was metabolized at the peripheral tissues but reliably reached the wound space. High amounts of Arg and ornithine (Orn) were detected in the specimens considered. No changes on citrulline (Ctr) or NO concentrations were observed, overall suggesting that, during the period studied, the arginase pathway predominated. The acute scarring response differed significantly in the two placements considered. The P-SS interface evidenced more extensive new tissue growth than the P-DS interface. Forty-eight hours after mesh implantation cellular infiltration, fibroblast proliferation, and mesh-surrounding angiogenesis were higher in the arginine-treated rats. Type III collagen staining was related to arginine treatment, being higher (++) in the study group. In conclusion, and independently of the site of mesh placement, supplemental Arg seemed to favorably affect early local collagen deposition. This could be potentially helpful to ameliorate the integration of biomaterials into the tissues and, consequently, to allow for the design of more selective therapeutic strategies to prevent hernia recurrence rates.

Abdominal Muscles↗
PubMed1997

Relationship between lipoprotein(a) phenotypes and albumin excretion rate in non-insulin-dependent diabetes mellitus: protective effect of 'null' phenotype?

The possible association between lipoprotein(a) [Lp(a)] and albumin excretion rate (AER) is a topic that generates conflicting views. In addition, Lp(a) phenotypes have not previously been considered as factors influencing AER. In order to clarify this issue, we studied 70 non-insulin-dependent diabetes mellitus (NIDDM) patients without clinically detectable macroangiopathy, 27 with microalbuminuria and 43 without it. Both groups were matched for the known variables that could influence AER and serum Lp(a) levels. Lp(a) was determined by enzyme-linked immunosorbent assay (ELISA), and Lp(a) phenotypes were assessed by electrophoresis followed by immunoblotting. Lp(a) phenotypes were grouped as follows: 'small' (F, S1 and S2), 'big' (S3 and S4) and 'null'. The NIDDM patients with microalbuminuria presented higher serum Lp(a) concentrations than the patients without it [15.7 mg dL-1 (95% CI 0.5-36.5) vs. 4.5 mg dL-1 (95% CI 0.1-18.5); P < 0.001] and a direct correlation between Lp(a) and AER was observed (r = 0.34; P < 0.01). AER was significantly different when Lp(a) phenotypes were considered ['small': median 19 micrograms min-1 (range 1-195); 'big': median 9.5 micrograms min-1 (range 1-186); 'null': 4 micrograms min-1 (range 1-9); P = 0.04]. None of the NIDDM patients with a 'null' phenotype showed an AER of > 10 micrograms min-1. In conclusion, this case-control study provides evidence that microalbuminuria is associated with high serum Lp(a) in NIDDM without clinically detectable macroangiopathy. Furthermore, NIDDM patients with a 'null' phenotype could be considered at low risk for the development of microalbuminuria.

Aged↗
PubMed1996

Prospective case control study to determine the effect of lovastatin on serum testosterone and cortisol concentrations in hyperlipidemic nephrotic patients with chronic renal failure.

In order to investigate the effects of lovastatin on adrenal and gonadal function, we prospectively determined the basal and gonadorelin-stimulated concentrations of testosterone, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) and the cortisol response to adrenocorticotropic hormone (ACTH) in a sample of 25 male patients with advanced chronic renal failure, hypercholesterolemia and proteinuria. Hormone studies were done prior to and after lovastatin treatment. The values of these patients were compared with those of a matched healthy control group. Before starting treatment with lovastatin, the patients showed significantly lower testosterone concentration and higher LH concentration than the control group. After stimulation with gonadorelin, they also showed a lower increase in testosterone and LH. After 12 months of lovastatin treatment, a significant decrease in the concentration of cholesterol, LDL C, VLDL C and apo B was observed, but neither the basal testosterone concentration nor the response to gonadorelin stimulation was modified. Before treatment, basal and ACTH-stimulated serum cortisol levels did not differ from those of the control group. After lovastatin treatment, neither the basal serum cortisol levels nor the response to ACTH was modified. We conclude that in the patients studied, although the decrease in testosterone concentration may be partially attributable to a decrease in its synthesis, lovastatin treatment does not increase testosterone deficit. This is either because this drug does not inhibit gonadal hydroxymethylglutaryl CoA reductase at the does given or because the cholesterol which LDL C provides the cell with is enough to maintain testosterone synthesis.

Adult↗
PubMed1995

Serum lipoprotein (a) levels in patients with chronic renal failure--evolution after renal transplantation and relationship with other parameters of lipoprotein metabolism: a prospective study.

In order to analyze the relationship between lipoprotein (a) [Lp (a)] and other lipoproteins during chronic renal failure and once renal function is restored after kidney transplantation, we determined the serum levels of total lipoprotein, high-density lipoprotein, low-density lipoprotein, and very-low-density lipoprotein cholesterols, total and very-low-density lipoprotein triglycerides, apolipoproteins A-I, B, C-II, C-III, and E, and E, and Lp (a) in 30 patients with chronic renal failure before and 12 months after renal transplantation. During the 1st year after transplantation, all patients were treated only with ciclosporin and prednisone and had serum creatinine levels < 1.6 mg/dl (140 mumol/l) and proteinuria < 500 mg/day. No patients had chronic hepatic disease. To determine reference values we studied a control group of 60 healthy volunteers. Before renal transplantation, the study group showed higher concentrations of triglycerides, very-low-density triglycerides, very-low density lipoprotein cholesterol, apolipoproteins, C-II and C-III, and Lp(a) than the control group. There was no correlation between Lp(a) and any of the studied variables. After renal transplantation, the serum levels of total lipoprotein, high-density lipoprotein, and low-density lipoprotein and apolipoproteins A-I and B increased significantly. Apolipoproteins C-II and C-III and Lp(a) decreased and normalized. After these changes had taken place, there was no relationship between Lp(a) and other parameters of lipoprotein metabolism. We conclude that the increase in Lp(a) during the chronic renal failure phase is basically related to the loss of renal function and does not depend on the resultant alterations which are produced in other lipoprotein variables.

Adult↗