Search PubMed⌕ Search

Biomedical subjects

C Prieto

Publications and source records attributed to C Prieto.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Pre-hepatic portal hypertension as a late complication of liver transplantation in children].

UNLABELLED: In the long-term after liver transplantation (LT), some children develop prehepatic portal hypertension (PPH) and raise problems not very well known yet; many of the lessons learned with the management of these patients may be useful outside the LT. AIM: 1. To analyze the incidence and risk factors of PPH after LT. 2. To evaluate the results with the different treatments used. METHODS: Retrospective study over 164 children surviving more than 1 year after LT. Univariant analysis of possible risk factors associated and multivariant (logistic regression), for those that had significance in the univariant analysis. Other factors associated are analyzed as well as the indications and results of two types of treatment: percutaneous pneumatic dilatation and surgical shunt (splenorenal and Rex shunt). RESULTS: 9 children developed symptomatic PPH (hemorrhage in 8, ascites in 1), associated to lymphoproliferative post-LT disease in 2, and to anastomotic biliary stricture in 1. The age at first LT (children under 1 year old), weight (below 10 kg), and need of retransplantation (reLT) were in the univariant analysis the associated variables with increased risk of PPH. The diagnosis (biliary atresia) and the emergency status of the LT were almost significative. In the multivariant analysis, the need of reLT is the only independent variable that increases the risk (relative risk: 4.5, confidence interval 95%: 1.29-18.87). At diagnosis 3 cases showed portal estenosis, and 5 showed absence of permeability with cavernomatous transformation. The PPH was caused in one case because of the esplenic vein disconnection (treatment not required at the moment); the three cases of portal estenosis were dilated percutaneously with success, and 2 of the 5 cases with portal thrombosis have been surgically shunted: one by an splenorenal shunt and the other by a Rex shunt (first case done in Spain); the other 3 cases are stable waiting for a surgical solution. The hepatic function is normal in the 9 cases. CONCLUSIONS: The PPH can complicate the prognostic of the pediatric LT in the long term. The treatment depends on the permeability of the portal trunk. Whenever possible, percutaneous dilatation should be attempted; should surgery be required, the Rex shunt is the best option.

Child↗
PubMed2000

Benzothiadiazine dioxide dibenzyl derivatives as potent human cytomegalovirus inhibitors: synthesis and comparative molecular field analysis.

The benzothiadiazine dioxide (BTD) derivatives are potent nonnucleoside human cytomegalovirus (HCMV) inhibitors. As part of our comprehensive structure-activity relationship study of these compounds, we have now synthesized N,N- and N,O-dibenzyl derivatives with different para-substituents (alkyl, phenyl, electron-donating, electron-withdrawing) in the phenyl ring of the benzyl moieties. The antiviral activity against HCMV (AD-169 strain) was also experimentally measured showing IC(50) values between 2.5 and 50 microM. Comparative molecular field analysis (CoMFA) was employed to generate a model, based upon 32 diverse BTD derivatives, to delineate structural and electrostatic features important for enhanced activity against HCMV. The steric (van der Waals) interactions with the receptor majoritary describes the variation in antiviral activity among the inhibitors. Finally, the CoMFA model was used to design two sets of novel BTD derivatives. Synthesis and subsequent anti-HCMV evaluation of these compounds enabled us to maintain the activity of this new kind of HCMV inhibitors.

Antiviral Agents↗
PubMed2000

Nonnucleoside human cytomegalovirus inhibitors: synthesis and antiviral evaluation of (chlorophenylmethyl)benzothiadiazine dioxide derivatives.

A second generation of benzothiadiazine dioxide (BTD) derivatives was synthesized employing benzylation reactions mainly. The chlorophenylmethyl BTD derivatives showed activity against human cytomegalovirus (HCMV) with IC(50) values ranging from 3 to 10 microM. Their 50% cytotoxic concentrations were often >200 microM to lung fibroblast HEL cell proliferation and between 20 and 35 microM for lymphocyte CME cell growth. When cytotoxicity for cell morphology was considered, the minimum cytotoxic concentration for the different BTD derivatives varied between 5 and 200 microM. Some of the anti-HCMV compounds also showed activity against HIV-1 and HIV-2. The chlorophenylmethyl derivative 21 was active against a variety of HCMV clinical isolates from patients with different clinical manifestations and fully maintained its activity against a ganciclovir-resistant HCMV strain. The dibenzyl BTD derivatives did not inhibit HCMV protease, and preliminary pharmacological experiments revealed that their anti-HCMV action stems from interference with an early stage of the viral replicative cycle.

Animals↗
PubMed2000

Influence of two dietary fibers in the oral bioavailability and other pharmacokinetic parameters of ethinyloestradiol.

Dietary fibers are widely used in hypoglycaemic, hypolipidemic, slimming diets. It is probable that their ingestion coincides with the oral administration of drugs and a modification of their pharmacokinetics can appear. In the present study, the influence of two soluble fibers (guar gum and psyllium) was evaluated on the pharmacokinetics of ethinyloestradiol (EE) when they were administered together to female rabbits via the oral route. Three groups of rabbits were used. All animals received 1 mg/kg of EE; this compound was administered alone in the control group and with 3.5 g of guar gum or psyllium in the other two groups. When guar gum was administered, there was a decrease in the extent of EE absorbed, but no change was observed in the rate of absorption. When psyllium was administered, the extent of EE absorbed increased slightly and the rate of absorption was slower.

Administration, Oral↗
PubMed1999

Chlorophenylmethyl benzothiadiazine dioxides derivatives: potent human cytomegalovirus inhibitors.

Modifications of our previously reported lead compounds, acyclonucleosides derived from 2,1,3-benzothiadiazine dioxides, in the search for inhibitors of human cytomegalovirus (HCMV), lead us to identify the chlorophenylmethyl benzothiadiazine dioxides derivatives as potent HCMV inhibitors. The synthesis and antiviral data of this second-generation of benzothiadiazine dioxide compounds are reported.

Anti-Infective Agents↗
PubMed1999

Complete duplication of bladder and urethra in the coronal plane in a girl: case report and review of the literature.

An unusual case of complete duplication of the bladder and urethra in the coronal plane associated with left ectopic kidney, duplication of the clitoris and a chondrolipomatous malformation in the pelvic region in a girl is reported. The accessory bladder was located posterolateral to the normal bladder and a ureteric opening into the accessory bladder was found. The malformation was initially identified by US and cystography and confirmed by cystoscopy.

Abnormalities, Multiple↗
PubMed1999

Late biliary complications in pediatric liver transplantation.

PURPOSE: The aim of this study was to review the biliary complications occurring in late follow-up after liver transplantation in children. METHODS: The medical records of 135 children who received orthotopic liver transplantations (OLT) and had graft survival of more than 1 year were reviewed. Technical variants using a reduced-size graft were applied in 32 (23.7%). For biliary reconstruction, 15 patients had choledochocholedochostomy and 120 a Roux-en-Y loop. Biliary reoperation in the early post-OLT period was needed in 24 patients (17.7%). Routine checking of liver function and duplex Doppler ultrasonography (DDS) were performed during the follow-up period, which averaged 58 months. Late biliary complication was defined as that occurring after the first hospital discharge. RESULTS: Late biliary complications occurred in 18 children (13.3%); 16 showed symptoms or analytical disturbances in liver function tests. The Diagnoses included uncomplicated cholangitis (n = 6), anastomotic biliary stricture (n = 7), ischaemic damage of the biliary tree (n = 3) including one late (28 months) hepatic artery thrombosis leading to an intrahepatic biloma. and bile leak after T-tube removal (n = 2). The six children with uncomplicated cholangitis had no repeat episodes in follow-up despite persistent aerobilia. Six patients affected by anastomotic strictures were treated successfully with percutaneous dilatation and, if present, stone removal. Persisting dysfunction and cholangitis occurred in one case affected by ischaemic biliary disease. Biliary leaks after T tube removal settled spontaneously. Risk factors for late biliary complications were determined. There was no relation to the cold ischaemia time, type of graft or biliary reconstruction, or previous early post-OLT biliary reoperation. Aerobilia (affecting 21.5% of OLT patients) was related to cholangitis (P = .001). CONCLUSIONS: Anastomotic strictures, reflux of intestinal contents via the Roux-en-Y loop, and residual ischaemic damage led to late biliary complications in 12% of paediatric OLT patients. Evidence of biliary dilatation on DDS may be delayed in anastomotic strictures; in these cases the results of percutaneous treatment were excellent. Children with aerobilia have and increased risk of cholangitis.

Analysis of Variance↗
PubMed1999

[Pediatric liver transplantation: now the patients are different and the problems are different as well].

AIM: 1. To show how in a program of pediatric liver transplantation (PLT) with 12 years of experience, the continuous use of technical innovations has allowed to improve the results and to treat the most complex cases. 2. To point out that when the immediate results of the transplant improve and the evolution time get longer, the late complications become the main source of concern. MATERIAL AND METHODS: The graft survival and the incidence of early surgical complications was compared between the first 100 PLT and the last 100 PLT (Total 235 PLT). The patients survival was also compared between the first and the last 5 years. In every case it was analyzed the age and weight of the children at the time of the transplant and the type of graft (full or reduced liver). The incidence of late complications in the global series was also analyzed, especially the posttransplant lymphoproliferative disease (PTLD) and the late biliary and vascular complications. RESULTS: There are significant differences between the first 100 PLT and the last 100 PLT in relation with the age of the patients (6.8 +/- 0.6 vs 4.2 +/- 0.5 years), the number of children younger than 1 year (4 vs 28), weight (22.4 +/- 1.2 vs 16.9 +/- 1.7 kg), number of PLT in children under 10 kg (7 vs 43), use of reduction techniques (7 vs 49), rate of hepatic artery thrombosis (12% vs 3%), and rate of early biliary complications (13% vs 4%). The 5 years survival of the graft was 51% in the first 100 PLT vs 65% in the last 100 PLT, and the 5 years patients survival was 70.1% in the first 5 years of the program vs 79.6% in the last 5 years. Among the late complications in the global series, 13 cases of PTLD (2 deaths) have special relevance, 6 cases of late anastomotic biliary stricture, 4 cases of portal stenosis, 1 arterial thrombosis, 1 death due to a fulminant sepsis and another death because of a colitis with multiple hepatic abscess. CONCLUSIONS: 1. The result of PLT improve, despite of the fact that in the last years the difficulty of the surgical procedures have increased (the patients are younger, with less weight and the reduction techniques are used more frequently). 2. The late complications have a significant influence in the prognosis, being that influence not completely established yet.

Age Factors↗
PubMed1998

Long-term follow-up of patients with biliary atresia successfully treated with hepatic portoenterostomy. The importance of sequential treatment.

The outcome of 18 biliary atresia (BA) patients (5 male, 13 female; age range 10.7-22.5 years; mean 15.4+/-0.7 years) treated with hepatic portoenterostomy (HPE) and jaundice-free for more than 10 years without liver transplantation (LT) is analyzed retrospectively. Eight of these patients subsequently required LT (age at LT 12. 8+/-0.5 years, range 10.5-15.2 years); 3 children (aged 11.6, 13.2 and 14.1 years, respectively) had episodes of gastrointestinal variceal bleeding associated with other signs of severe disease and are now candidates for LT; and among the 7 asymptomatic patients (age range 11.2-22.5 years; mean 15.9+/-2.1 years), 5 had sonographic and biochemical signs of moderate portal hypertension (PH). In order to analyze whether the age at transplantation influences the survival of children transplanted for BA, we also reviewed the outcome of 71 BA patients transplanted at our hospital between 1986 and 1996. All the children older than 10 years at the time of LT were alive; only patients younger than 10 years died following LT (n = 15). We conclude that the natural outcome of extrahepatic BA is toward PH, fibrosis, and cirrhosis, even in those cases successfully treated with HPE. In our experience, the results of sequential treatment with HPE and LT were excellent.

Adolescent↗
PubMed1998

[99mTc red blood cell scintigraphy for the assessment of active gastrointestinal bleeding].

BACKGROUND: 99mTc red blood cell scintigraphy is a non invasive diagnostic method for low flow gastrointestinal bleeding. AIM: To assess the diagnostic yield of this method in patients admitted with gastrointestinal bleeding in whom upper gastrointestinal endoscopy was negative. PATIENTS AND METHODS: The clinical records of 59 patients, aged 6 to 90 years old (35 male), with active gastrointestinal bleeding subjected to a 99mTc red blood cell scintigraphy were reviewed. All had non diagnostic upper gastrointestinal endoscopic studies, and in 20 a selective arteriography was performed. RESULTS: In 40 patients the scintigraphy was positive for gastrointestinal bleeding, and in 57% of these the exam was positive during the first hour. Fifteen of the 19 patients with a negative scintigraphy did not have an active clinical bleeding at the moment of the examination. In 24 patients, a final etiological diagnosis was reached. In 93% of these patients scintigraphy correctly identified the bleeding site. In one patient with a negative scintigraphy, angiography disclosed a pseudo aneurysm of the splenic artery that was not bleeding actively. CONCLUSIONS: In these patients with negative upper gastrointestinal endoscopy 99mTc red blood cell scintigraphy had a 91% sensitivity for the diagnosis of active gastrointestinal bleeding.

Adolescent↗
PubMed1997

Transplacental infection following exposure of gilts to porcine reproductive and respiratory syndrome virus at the onset of gestation.

Twenty-five gilts without measurable porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV) serum antibody titres were used for this experiment. All of them were randomly assigned to one of the treatment groups at the time of artificial insemination. Twelve gilts were exposed to PRRSV, of these, six were slaughtered on day 10 after exposure and constituted group A. The remaining six were slaughtered on day 20 after infection and constituted group C. Thirteen gilts were used as controls, six of these were slaughtered on day 10 after treatment and constituted group B. The remaining seven were slaughtered on day 20 after treatment and constituted group D. The infected gilts were inoculated with PRRSV intranasally and intravenously in the ear vein. They were observed for clinical signs of infection and the effects on conception and fertilization rates were studied, while the gilts and their embryos were tested for PRRSV and homologous antibodies. The infected animals developed signs of PRRS associated with anorexia and slight pyrexia. Infection was verified by reisolation of the virus from serum and other tissue samples and also by seroconversion. Ten out of 12 infected gilts and 10 out of 13 controls were pregnant at the time of slaughter and the ratio of embryos to corpora lutea was the same in both, infected and control groups (0.75). Therefore, infection with PRRSV at the onset of gestation did not appear to interfere with conception and fertilization rates and subsequent pregnancy. The PRRSV was not isolated from any of the embryos collected at day 10 postexposure, but was present in 20-day-old embryos of group C gilts. In this group, 60% of litters were infected prenatally, with 16% of embryos infected. The proportion of dead embryos was three times greater than in a control group D (35.4% and 9.8%, respectively). The results of this report indicate that exposure of susceptible gilts to PRRSV at the onset of gestation has no significant effect on conception and fertilization rates. However, although infection does not appear to have any effect on the embryos before implantation, it can result in transplacental infection and embryo death.

Animals↗
PubMed1997

Feline heartworm (Dirofilaria immitis) infection: detection of specific IgG for the diagnosis of occult infections.

Sera from 54 cats, 53 asymptomatic and one symptomatic (chronic dyspnoea and coughing), living in a hyper-endemic area for canine heartworm (Dirofilaria immitis) infection were studied to evaluate the reliability of two ELISA-based antibody tests coupled with both somatic (ELISASA) and excretory/secretory (ELISAE/S) antigens. All cats were examined by echocardiography and radiography. In addition, an ELISA-based test to detect adult female heartworm circulating antigens and a modified Knott test for microfilariae in the blood were carried out on all cats. No cat was positive for microfilariae in the blood. Heartworms were visualized in 12 of 54 cats by echocardiography. Of these, three asymptomatic cats and the symptomatic one had radiographic signs of infection and were the only ones positive for heartworm circulating antigens. All sera except two were positive when analyzed in ELISA(SA). In ELISA(E/S), nine sera were positive but three were negative. No sera from the 42 echocardiography-negative cats was positive in ELISA(E/S), but 11 were positive in ELISA(SA). Western blot analyses with somatic antigens of sera from echocardiography-positive cats showed at least four bands of recognition between 19 and 30 kDa and one of about 40 kDa. With E/S antigen, a large band of about 22 kDa and one of about 25 kDa were recognized; these appear to be most specific.

Animals↗
PubMed1997

Syndrome of Alagille: radiological and sonographic findings. A review of 37 cases.

The objective of this study was to evaluate the association of intrahepatic cholestasis, pulmonary stenosis, and hyperlipemia with osseous and renal abnormalities in Alagille's syndrome. A total of 37 patients (25 males and 12 females) with ages ranging between 8 months and 27 years were included. Clinical records as well as radiological and ultrasonographic studies were reviewed. Chronic cholestasis was observed in all patients. Thirteen had favorable clinical outcome and normal hepatic sonograms. Clinical and sonographic evidence of portal hypertension was found in 13 patients and of cirrhosis in 8 patients. The remaining 3 patients required hepatic transplantation due to severe cholestasis. Hyperlipemia correlated with hepatic malfunction. Pulmonary stenosis and renal hypoplasia were the most frequently associated abnormalities. All patients showed a peculiar facies. Abnormal "butterfly" vertebrae were present in 18 patients and ulnar or phalangeal shortening in 11 patients. Ultrasonography allowed hepatobiliary disease assessment and helped to establish indications for hepatic transplantation. Renal and osseous abnormalities were not specific but in the appropriate clinical setting reinforced the diagnosis.

Adolescent↗
PubMed1997

Insemination of susceptible and preimmunized gilts with boar semen containing porcine reproductive and respiratory syndrome virus.

Twenty-one gilts without measurable PRRSV serum antibody titres were identified for this experiment. Seven gilts were used as controls (Group C) and 14 as principals. Of these, 7 gilts were preimmunized to PRRSV and constituted Group B, while 7 gilts remained seronegative and constituted Group A. The principal gilts were inseminated with boar semen containing PRRSV and were killed 20 d later. The control gilts were treated similarly but were not exposed to PRRSV. Gilts were observed for clinical signs of infection. The effects on the conception rates were studied and gilts and embryos were tested for PRRSV and homologous antibodies. Group A and B gilts developed signs of PRRS associated with anorexia and slightly elevated body temperatures. Transmission of the infection was demonstrated by the isolation of PRRSV from serum and other tissue samples of principal gilts and also by seroconversion. The results show that early infection may have an insignificant effect or no effect on the conception and fertilization rates. However, exposure to PRRSV at the time of insemination can result in transplacental infection of embryos. In Group A gilts, 5 of 6 litters were infected prenatally with 7.6% of embryos infected. In Group B gilts, 1 of 5 litters and 1.3% of embryos were infected. Moreover, approximately 2 and 4 times more embryos were dead in litters of gilts from Group A and Group B than in gilts from control Group C. The isolation of PRRSV in 3 dead embryos suggests that the embryos may have died as a result of the direct effect of the virus. It can be concluded that the insemination of either seronegative or preimmunized gilts with boar semen containing PRRS V may have an insignificant effect or no effect on conception and fertilization rates, although it can result in transmission of the virus and embryonic infection and death.

Journal Article↗
PubMed1997

The energy costs of walking on the level and on negative and positive slopes in the Granadina goat (Capra hircus).

The energy expenditure of six goats averaging 35 (SE 0.3) kg was measured when the animals were standing or walking on a treadmill enclosed in a confinement-type respiration chamber at different speeds (0.167, 0.333 and 0.500 m/s) and slopes (-10, -5, 0, +5 and +10%). The energy costs of locomotion, estimated from the coefficients of linear regressions of heat production (HP) per kg body weight v. distance travelled were 1.91, 2.33, 3.35, 4.68 and 6.44 J/kg BW per m for -10, -5, 0, +5 and +10% inclines respectively, indicating that the energy expenditure of walking over standing changes with slope according to a slightly curvilinear relationship. The energy cost of raising 1 kg body weight one vertical metre was found to be 31.7 J, giving an average efficiency for upslope locomotion of 30.9%. The energy recovered on vertical descent was estimated as 13.2 J/kg per m, indicating an efficiency of the energy recovered above the theoretical maximum.

Animal Nutritional Physiological Phenomena↗
PubMed1997

Effect of a low protein diet on the energy metabolism of growing chickens.

Two slaughter experiments were carried out to determine whether the protein content of the diet has an influence upon the efficiency of utilization of ME in fast growing chickens. A normal-protein diet (NPD, 204 g CP/kg DM: 14.7 MJ ME/kg DM) based on soybean meal as the sole source of protein was given at four different levels of intake (ad libitum or restricted at about 90, 65 and 40% ad lib) to 10-d-old animals for 2 weeks. In a parallel experiment the chickens were fed ad libitum a low protein diet (LPD, 66 g CP/kg DM: 15.0 MJ ME/kg DM) based on soybean meal. The intake of metabolizable energy ranged from 1675 to 777 and 1770 to 832 kJ/kgW0.75 per day for NPD and LPD treatments, respectively. Mean values of energy retention, gross efficiency of energy utilization and energy retained as protein were significantly (P < .05) lower and heat production (expressed as both kJ/kgW0.75 per day and kJ/kg body protein content0.75 per day) was significantly higher (P < .05) for the chickens fed on LPD. These findings support the concept of dietary-induced thermogenesis in response to reductions in dietary protein concentration. It is concluded that the increased heat production found in the birds fed on the low-protein diet can be explained by both an increase in energy requirements for maintenance (MEm) and a sharp decrease in the efficiency of utilization of ME of growth (k(g)).

Animal Nutritional Physiological Phenomena↗