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E Gonzalez

Publications and source records attributed to E Gonzalez.

At least 19 recordsLinked to original sources
PubMed2006

Vibrational spectra of germanium-carbon clusters in solid Ar: identification of the nu4(sigma(u)) mode of linear GeC5Ge.

The linear GeC(5)Ge cluster has been detected in Fourier transform infrared spectra observed when the products from the dual laser evaporation of carbon and germanium rods were trapped in solid Ar at approximately 10 K. Comparison of (13)C isotopic shift measurements with the predictions of density functional theory calculations at the B3LYP/cc-pVDZ level confirms the identification of the nu(4)(sigma(u)) mode of GeC(5)Ge at 2158.0 cm(-1).

Journal Article↗
PubMed2005

Once-daily antiretroviral therapy: Spanish Consensus Statement.

BACKGROUND: Administration of antiretroviral therapy (ART) once daily is creating extraordinary interest among the members of the scientific community and also among those who receive the therapy. However, in clinical practice, some doubts remain about its use. OBJECTIVES: This document examines the characteristics and possibilities of treatment administered once daily. METHODS: Consensus of 248 Spanish experts in the field. RESULTS: Once-daily dosing is considered an added value which could favour adherence and, therefore, efficacy, as well as the quality of life of certain patients, however, the objective of adequate adherence in the long term is often difficult to achieve regardless of the treatment used. In theory, any patient can receive once-daily therapy, although some patients could particularly benefit from it, e.g. those with unfavourable social or personal circumstances, including drug users, patients whose treatment must be supervised, patients receiving multiple medications, or those who need rescue therapy after multiple treatment failures. At present, it is possible to design once-daily ART using some of the combinations of drugs considered as first-choice in national and international recommendations for antiretroviral therapy, but the options are still limited. The marketing of new drugs with this characteristic could allow us to increase the number and types of patient who can benefit from once-daily regimens, including those patients who need rescue therapy. CONCLUSIONS: Once-daily ART is a good alternative to regimens administered several times each day when a potent combination of active drugs is available.

Anti-HIV Agents↗
PubMed2005

Rapamycin at six years can exhibit normal renal function without proteinuria or neoplasia after renal transplantation. A single-center experience.

Currently, long-term experience with Rapamune (RAPA) after renal transplantation is scarce. We present our experience with RAPA in patients who were included in clinical trials. Between 1996 and 1999, 27 renal transplant patients received RAPA alone or in combination with cyclosporine (CyA). We study 15 of them (9 males, 6 females; mean age 36 years) who are currently functioning with a mean follow-up of 6 years (range, 5.2-8 years). The presence of delayed graft function was 40% and acute rejection 26.6%, all of them controlled with steroids. Notably, no patients experienced an acute rejection episode after the first year. Among 15 patients, 12 received steroids, RAPA and CyA; and 3 received steroids, RAPA, azathioprine (AZA) or mycophenolate mofetil (MMF) for immunosuppression. At the end of follow-up, the situation was the opposite: 12 patients received steroids (2.5-5 mg/d) and RAPA associated with or without AZA/MMF, and 3 were maintained with steroids, RAPA and CyA. Renal function was excellent in the entire group: mean SCr 1.1 mg/dL (range, 0.7-1.8) with mean RAPA blood levels (HPLC) of 11 ng/dL (range 8-16). Hyperlipidemia was universal with all patients (100%) receiving statins maintaining acceptable levels of cholesterol (mean 209 +/- 28 mg/dL) and tryglycerides (mean 154 +/- 76 mg/dL). Arterial hypertension present in 12 of 15 (80%) patients was controlled with a mean of 1.5 drugs. Notably, no patient presented with proteinuria, neoplasia, posttransplant diabetes, or cardiovascular events. In conclusion, these single-center results suggest that Rapamune may be useful in the long-run after renal transplantation. The presence of normal renal function and the absence of proteinuria and neoplasia in these renal transplant patients may have important clinical implications.

Adrenal Cortex Hormones↗
PubMed2005

15-Deoxy-Delta12,14-prostaglandin J2 and peroxisome proliferator-activated receptor gamma (PPARgamma) levels in term placental tissues from control and diabetic rats: modulatory effects of a PPARgamma agonist on nitridergic and lipid placental metabolism.

15-Deoxy-Delta(12,14)-prostaglandin J2 (15dPGJ2) is a peroxisome proliferator-activated receptor (3) (PPAR(3)) ligand that regulates lipid homeostasis and has anti-inflammatory properties in many cell types. We postulated that 15dPGJ2 may regulate lipid homeostasis and nitric oxide (NO) levels in term placental tissues and that alterations in these pathways may be involved in diabetes-induced placental derangements. In the present study, we observed that, in term placental tissues from streptozotocin-induced diabetic rats, 15dPGJ2 concentrations were decreased (83%) and immunostaining for nitrotyrosine, indicating peroxynitrite-induced damage, was increased. In the presence of 15dPGJ2, concentrations of nitrates/nitrites (an index of NO production) were diminished (40%) in both control and diabetic rats, an effect that seems to be both dependent on and independent of PPAR(3) activation. Exogenous 15dPGJ2 did not modify lipid mass, but decreased the incorporation of (14)C-acetate into triacylglycerol (35%), cholesteryl ester (55%) and phospholipid (32%) in placenta from control rats, an effect that appears to be dependent on PPAR(3) activation. In contrast, the addition of 15dPGJ2 did not alter de novo lipid synthesis in diabetic rat placenta, which showed decreased levels of PPAR(3). We conclude that 15dPGJ2 modulates placental lipid metabolism and NO production. The concentration and function of 15dPGJ2 and concentrations of PPAR(3) were altered in placentas from diabetic rats, anomalies probably involved in diabetes-induced placental dysfunction.

Acetates↗
PubMed2005

The role of alterations in arachidonic acid metabolism and nitric oxide homeostasis in rat models of diabetes during early pregnancy.

The diabetic pathology induces reproductive abnormalities that enhance spontaneous abortion, congenital anomalies and neonatal morbidity/mortality rates, abnormalities that begin with an altered female gamete. In this review we focus on the damage induced by maternal hyperglycemia during ovulation, early embryo development, implantation and embryo organogenesis in experimental rat models of diabetes. Hyperglycemia can induce cellular damage by enhancing the production of reactive oxygen species (ROS), by altering arachidonic acid metabolism (thus leading to altered production of prostaglandins such us PGE(2)and 15deoxydelta(12-14)PGJ(2), involved in signalling and developmental pathways), and by enhancing the generation of nitric oxide (a mediator of many cell functions including apoptotic cell death). In maternal diabetes all of these abnormalities are present from the oocyte stage, during embryonic implantation, and during embryo organogenesis. The involvement of these alterations in embryo loss and congenital malformations due to diabetes and the cross-talk among these metabolic pathways are discussed. As maternal hyperglycemia induces damage from the oocyte stage and throughout embryo development the data reviewed suggests the need of strict preconceptional metabolic control. The importance of the molecules involved in hyperglycemia-induced damage as future pharmacological targets for intervention is discussed.

Animals↗
PubMed2004

Influence of peroxisome proliferator-activated receptor gamma activation by its endogenous ligand 15-deoxy Delta12,14 prostaglandin J2 on nitric oxide production in term placental tissues from diabetic women.

Diabetes induces alterations which condition placental remodelling. The levels of nitric oxide (NO) (a modulator of placental invasiveness, differentiation and proliferation) were higher in term placental explants from diabetic patients when compared to controls. Peroxisome proliferator-activated receptor gamma (PPARgamma) activation by its endogenous ligand 15-deoxy Delta(12,14)prostaglandin J(2) (15dPGJ(2)), is a differentiating factor of adipocytes and other cell types, such as trophoblasts. 15dPGJ(2) is also able to down-regulate NO production in different cell types. Our study evaluated the levels of 15dPGJ(2) and PPARgamma and the influence of PPARgamma activation by 15dPGJ(2) on the production of NO, in term placental tissues from control, pre-gestational and gestational diabetic patients. Our results showed that 15dPGJ(2) was present in human term placenta, and that its levels were diminished in gestational (P<0.05) and pre-gestational (P<0.002) diabetic women when compared to controls. Exogenous 15dPGJ(2) addition (2 x 10(-6) mol/l) down-regulated NO production in placenta from control (P<0.001) and pre-gestational diabetic (P<0.01) patients, but failed to do so in gestational diabetic women, whose placental PPARgamma expression was diminished in comparison to controls (P<0.001). As the exogenous activation of PPARgamma prevented NO overproduction in placenta from pre-gestational diabetic women, it may have the potential to improve fetal outcome in this pathology.

Diabetes Mellitus, Type 1↗
PubMed2004

Plasma erythropoietin levels in the oldest old.

UNLABELLED: Erythropoietin (EPO) regulates erythrocytes production and is synthesized mainly by the kidney. Its production is reduced during chronic renal failure but is not altered by the senescence process in spite of the morphological changes that occur in the kidney. However, there is no information regarding what happens to erythropoietin synthesis during advanced ageing. Thus, we carried out an investigation to determine whether there was any significant difference in plasma erythropoietin between adults, old and very old people. MATERIAL AND METHODS: We studied 74 healthy volunteers: 22 adults, 30 old, and 22 very old. None of them were smokers or were suffering from any disease that may intefere with hemoglobin (Hb) levels or with EPO production. Hematocrit, Hb, plasma creatinine and plasma erythropoietin were measured, and creatinine clearance was calculated from serum creatinine using two different formulae. Statistical analysis was performed using ANOVA and Bonferroni tests. RESULTS AND CONCLUSION: Among the three groups we found a significant difference in creatinine clearance (p < 0.001), but not in plasma erythropoietin levels; we conclude that normal senescence does not alter plasma erythropoietin levels, even during advanced ageing.

Adolescent↗
PubMed2003

Helical computed tomography angiography is the most efficient test to assess vascular calcifications in the iliac arterial sector in renal transplant candidates.

UNLABELLED: The increased scope of renal transplant indications has lead to a larger number of recipients with vascular problems due to arterial calcifications in the iliac region. Compared to magnetic resonance and conventional arteriography, helical computed tomography angiography (HCTA) accurately depicts arterial diseases, including the location and extent of arterial calcification. The objective of this study was to assess the value of HCTA with maximum-intensity-projection (MIP) reconstruction to evaluate iliac arterial calcifications and stenosis among candidates for renal transplantation. MATERIAL AND METHODS: From December 1997 to March 2002, 114 HCTA scans with MIP reconstruction were performed in candidates for renal transplantation. Included patients fulfilled some of the following conditions: (a) older than 55 years, (b) diabetic, (c) second transplants, and (d) obvious vascular calcifications on plain abdominal x-ray. RESULTS: Among the 114 patients, 33 (29%) were excluded for transplantation due to universal calcification of the iliac arterial sector, and 81 (71%) were included on the waiting list due to the presence of calcium-free areas for the vascular anastomosis. Transplantation, which was attempted in 28 of the 81 patients, was successful in 25 using the area programmed after HCTA analysis. The transplants failed in three cases because no calcium-free area could be found upon surgical examination. CONCLUSION: HCTA with MIP reconstruction makes it possible to draw an exact map of the arterial calcifications of the iliac arterial sector, allowing better recipient selection and accurate planning for the vascular anastomosis and placement of the renal graft.

Angiography↗
PubMed2003

Comparative efficacy and side effects of the treatment of euthyroid goiter with levo-thyroxine or triiodothyroacetic acid.

Euthyroid goiter is usually treated with TSH-inhibitory doses of levo-T(4) (L-T(4)). Because triiodothyroacetic acid (TRIAC) decreases TSH levels, the following study was perfomed: 36 euthyroid goitrous female patients (no cancer or chronic thyroiditis) were randomized to TRIAC (19.6 micro g/kg) (n = 19) or L-T4 (1.7 microg/kg) (n = 17) treatment during 11 months. Goiter volume; lumbar and femoral bone mineral density; serum osteocalcin; deoxypyridinoline; TSH; free T(4); total, high-density lipoprotein, and low-density lipoprotein cholesterol; and triglycerides were measured before and after the study period. Student's t test and chi(2) analysis were performed. TSH values (microunits per milliliter) in the TRIAC and L-T(4) groups were: 1.91 +/- 0.6 (basal) and 0.180 +/- 0.1 (after) and 2.1 +/- 2.5 (basal) and 0.180 +/- 0.3 (after), respectively. Thyroid volume decreased 37.9 +/- 35.4% in the TRIAC patients and 14.5 +/- 39.5% in the L-T(4) group (P = 0.069). Forty-two percent of the goiters with TRIAC reduced more than 50% their initial volume vs. 17.7% with L-T(4) (P = 0.15). With TRIAC, patients experienced fewer side effects. No differences in the changes of bone mineral density, serum deoxypyridinoline, osteocalcin, or the lipid profile were observed between both groups. The present results show that TRIAC is more effective than L-T(4) in the reduction of goiter size, with comparable effects on peripheral parameters.

Adult↗
PubMed2002

Influence of push element geometry on the capture efficiency of push-pull ventilation systems in surface treatment tanks.

A full-scale installation which simulates a surface treatment tank provided with a push-pull ventilation system has been designed. This study examines the influence of the geometry of the push element on the capture efficiency of the system. It is observed that: (i) capture efficiency increases with the number of holes because of the continuous curtain formed, the size of the holes having no significant effect within the range studied (5-20 mm diameter); (ii) the push element is best supported on the tank wall so that no air from outside penetrates below the emitting jets because in this way the impact of the curtain on the tank occurs earlier and losses are less; (iii) the best results are obtained when the holes are directed downwards towards the tank surface at an angle of between 22 and 45 degrees.

Air Pollutants, Occupational↗
PubMed2002

Determination and interpretation of total and transversal linear efficiencies in push-pull ventilation systems for open surface tanks.

A real-scale pilot installation simulating an open surface treatment tank with a push-pull ventilation system has been designed. From experiments carried out, typical representations of the total and transversal linear efficiencies show that when total efficiency is related to push flow rate, taking as a parameter the pull flow rate, a parabolic profile is obtained with a maximum point or plateau that increases as the pull flow increases. When the transversal linear efficiency is analysed, three general zones where losses occur to the exterior can be detected: (i) when the push flow rate is low, any distortion in the wall jet, whether external (e.g. in the air flow inside the workshop) or internal (e.g. thermal effects), provokes an escape from contaminant; (ii) in the impact zone, where the push flow impacts on the tank surface, distortion increases as the push flow rate increases; (iii) when the push/pull flow rate ratio increases and preferential currents are produced inside the exhaust hood, these escape and cause substantial losses in efficiency.

Air Pollutants, Occupational↗
PubMed2002

Modulation of nitric oxide concentration and lipid metabolism by 15-deoxy Delta12,14prostaglandin J2 in embryos from control and diabetic rats during early organogenesis.

The concentration of 15-deoxy Delta(12,14)PGJ(2) (15dPGJ(2)) and its effects on nitric oxide generation and neutral lipid in embryos from control and neonatal streptozotocin-induced (n-stz) diabetic rats during organogenesis were investigated. 15dPGJ(2) is produced in embryos during organogenesis, and its production is lower in embryos of n-stz diabetic rats than in embryos from control rats. Nitrate and nitrite concentrations were higher in embryos from n-stz diabetic rats and were reduced in the presence of 15dPGJ(2) both in embryos from control and diabetic rats. Thus, decreased 15dPGJ(2) concentrations in embryos from n-stz diabetic rats may be related to the high nitric oxide concentrations found in those embryos. Exogenous 15dPGJ(2) decreased cholesterol and cholesteryl ester concentrations in embryos from control and n-stz diabetic rats, and reduced triacylglycerol concentrations in control embryos. Incorporation of [(14)C]acetate into lipids showed decreased de novo synthesis of cholesteryl ester and triacylglycerides in embryos from n-stz diabetic rats compared with controls. Exogenous 15dPGJ(2) reduced the incorporation of [(14)C]acetate into triacylglycerides, cholesterol and cholesteryl ester in embryos from both control and n-stz diabetic rats. 15dPGJ(2) is present in embryos during organogenesis, and reduces embryonic nitric oxide production and lipid synthesis. The lower 15dPGJ(2) concentration in embryos from n-stz diabetic rats may result in developmental alterations in this diabetic model.

Acetates↗
PubMed2001

Barrel cortex critical period plasticity is independent of changes in NMDA receptor subunit composition.

The regulation of NMDA receptor (NMDAR) subunit composition and expression during development is thought to control the process of thalamocortical afferent innervation, segregation, and plasticity. Thalamocortical synaptic plasticity in the mouse is dependent on NMDARs containing the NR2B subunit, which are the dominant form during the "critical period" window for plasticity. Near the end of the critical period there is a gradual increase in the contribution of NR2A subunits that happens in parallel to changes in NMDAR-mediated current kinetics. However, no extension of the critical period occurs in NR2A knockout mice, despite the fact that NMDA subunit composition and current kinetics remain immature past the end of the critical period. These data suggest that regulation of NMDAR subunit composition is not essential for closing the critical period plasticity window in mouse somatosensory barrel cortex.

Animals↗
PubMed2001

Concordance between the CC chemokine receptor 5 genetic determinants that alter risks of transmission and disease progression in children exposed perinatally to human immunodeficiency virus.

If CC chemokine receptor 5 (CCR5)-dependent mechanisms at the time of initial virus exposure are important determinants of virus entry and disease outcome, then the polymorphisms in CCR5 that influence risk of transmission and disease progression should be similar; this hypothesis was tested in a cohort of 649 Argentinean children exposed perinatally to human immunodeficiency virus type 1 (HIV-1). Two lines of evidence support this hypothesis. First, CCR5 haplotype pairs associated with enhanced risk of transmission were the chief predictors of a faster disease course. Second, some of the haplotype pairs associated with altered rates of transmission and disease progression in children were similar to those that we previously found influenced outcome in European American adults. This concordance suggests that CCR5 haplotypes may serve as genetic rheostats that influence events occurring shortly after initial virus exposure, dictating not only virus entry but, by extension, also the extent of early viral replication.

Acquired Immunodeficiency Syndrome↗