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A Avila

Publications and source records attributed to A Avila.

At least 19 recordsLinked to original sources
PubMed2006

Comparison of clinical, ultrasonographic, and biochemical differences at the beginning of puberty in healthy girls born either small for gestational age or appropriate for gestational age: preliminary results.

CONTEXT: There are limited and controversial data concerning puberty characteristics in girls born small for gestational age (SGA). OBJECTIVE: The objective of the study was to document clinical, ultrasonographic, and biochemical characteristics at the beginning of puberty in matched healthy girls born either SGA or appropriate for gestational age (AGA) recruited from the community. PATIENTS: Inclusion criteria were breast Tanner stage II and a body mass index between the 10th and 95th percentiles. INTERVENTIONS: Recruited subjects underwent a complete physical exam, bone age, and ultrasound measurements of the internal genitalia. Hormonal assessment included fasting early morning dehydroepiandrosterone sulfate, androstenedione, SHBG, inhibin-B, FSH, LH, estradiol (E2), 17-hydroxyprogesterone (17OH Prog), and testosterone. Thereafter, a GnRH agonist test (leuprolide 500 microg, sc) was performed with FSH and LH at time 3 and 24 h for E2, 17OH Prog, and testosterone. RESULTS: Sixty-five girls (35 AGA, 30 SGA) with a mean age of 9.9 +/- 1.03 (7.8-12.5) yr, similar bone age/chronological age (1.02 +/- 0.8 in AGA and 1 +/- 0.76 in SGA), median height of 1.35 +/- 0.06 cm, and similar waist to hip ratio were included. No differences in the presence of pubic hair, axillary hair, apocrine odor, or ultrasound measurements were found. SGA girls had increased baseline E2 as well as stimulated E2 and 17OH Prog. CONCLUSIONS: In a preliminary sample of lean, healthy girls recruited from the community born either SGA or AGA, we observed slight hormonal differences at the beginning of puberty. Longitudinal follow-up of this cohort will allow us to understand whether these differences are maintained and have a clinical impact in their pubertal development.

17-alpha-Hydroxyprogesterone↗
PubMed2006

Transplant renal artery stenosis: association with acute vascular rejection.

BACKGROUND: Transplant renal artery stenosis, the prevalence of which varies from 2% to 12%, is an important cause of hypertension and allograft dysfunction. We sought to determine the clinical characteristics of this disorder, assessing, predisposing factors, establishing treatment options, and examining patient outcomes. PATIENTS AND METHODS: Among 321 renal allograft recipients between November 1996 and December 2004, six patients were identified with this finding. We analyzed their clinical data before and after treatment compared with the 315 recipients face of the disorder. RESULTS: The six patients with the disorder were diagnosed within the first year (2 to 8 months; median 5.5 months). All patients displayed renal dysfunction, peripheral edema, and new-onset or uncontrolled hypertension at presentation. Abnormal Doppler findings were observed in 5 (83.3%) patients. The hemodynamically significant stenosis was successfully treated with percutaneous transluminal angioplasty (PTA) in all six. However, 3 (50%) patients displayed recurrent stenosis requiring a second PTA. The mean serum creatinine level decreased from a pre-PTA value of 4.4 +/- 1.8 mg/dL to a 1-month post-PTA value of 2.2 +/- 0.5 mg/dL (P = .027). Patients had no significant improvement in mean systolic and diastolic pressure. Vascular acute rejection episodes were more frequent among the affected than the control group (3/6; 50% vs 18/315; 5.7%; P < .001). No differences were found in age, sex, donor type, etiology of renal disease, immunosuppression, acute tubular necrosis, acute cellular rejection, cold ischemia time, or HLA matching. CONCLUSION: Transplant renal artery stenosis is a common cause of hypertension and renal allograft dysfunction. Acute vascular rejection is associated with this disorder.

Angioplasty, Balloon, Coronary↗
PubMed2006

Erythropoietin treatment in the sixth posttransplant month as a prognostic factor for renal allograft survival.

The purpose of this work was to assess the prognostic value of the need for erythropoietin (EPO) treatment at 6 months after transplantation. We retrospectively reviewed the outcomes of 143 consecutive cadaveric kidney transplants performed between January 2000 and April 2004, functioning at 6 months postransplantation. Patients were divided into two groups: group EPO6m (n = 24) received EPO treatment in the sixth month, and a control group (n = 119) did not receive EPO. Renal function deterioration (RFD) was considered to be a sustained decrease in creatinine clearance (CrCl) greater than 20% between the sixth month postransplant and the last visit. Mean follow-up was 38 +/- 16 months. The mean ages of the donor (57 +/- 9 vs 49 +/- 12 years; P = .001) and the recipient (59 +/- 12 vs 47 +/- 17 years; P = .000) were greater in the EPO6m group. Delayed graft function (83% vs 48%; P = .001) was more frequent in the EPO6m group. At 6 months after transplantation the EPO6m group showed lower hemoglobin (11.52 +/- 1.71 vs 13.32 +/- 1.69 g/dL; P = .000), higher serum creatinine (2.31 +/- 0.72 vs 1.65 +/- 0.53 mg/dL; P = .000), lower CrCl (33.53 +/- 10.83 vs 53.6 +/- 17.58 mL/min; P = .000), and similar proteinuria. RFD was more common in the EPO6m group (38% vs 10%; P = .026), with a different pattern of evolution of CrCl (-0.098 +/- 0.176 vs +0.093 +/- 0.396 mL/min/mo, P = .000). Multivariate analysis demonstrated that treatment with EPO at 6 months was the only predictor of RFD (RR 4.46; 1.58 to 12.58; P = .005). The need for EPO at 6 months postransplant was a good predictor of later renal allograft deterioration, more sensitive than serum creatinine or proteinuria.

Aged↗
PubMed2006

Treatment of central precocious puberty with triptorelin 11.25 mg depot formulation.

A new triptorelin 11.25 mg long depot formulation is now available for the treatment of central precocious puberty (CPP). The aim of our study was to evaluate the efficacy of triptorelin 11.25 mg administered every 90 days to suppress gonadotropin and sex steroid secretion and pubertal signs in children with CPP during 2 years of treatment. Inclusion criteria were clinical pubertal development before the age of 8 years in girls or 9 years in boys, advanced bone age and a pubertal LH response (peak >5 mIU/ml) to GnRH. We studied 20 patients (19 girls and 1 boy), with a median age at entry into the study of 7.5 +/- 0.2 years for girls, and 9 years for the boy. The basal and GnRH-stimulated serum levels of LH and FSH decreased significantly from baseline to 3 months of therapy (p <0.0001). All patients had a GnRH-stimulated peak below 3 mIU/ml between 6 and 24 months of treatment. The pituitary-gonadal axis recovered adequately after discontinuation of therapy. These results suggest that 3-month depot triptorelin is a satisfactory alternative for the therapy of children with CPP. The longer interval between injections may increase acceptability and compliance with treatment.

Breast↗
PubMed2006

[Renal transplantation with positive crossmatch].

INTRODUCTION: Lymphocytotoxic antibodies reduce the expectancy of renal transplantation due to the increased risk of a positive crossmatch. MATERIAL AND METHODS: We analyzed the evolution of eight kidney transplants performed in our unit in presence of a positive crossmatch with historical T and/or B lymphocyte positive crossmatches. RESULTS: Mean panel reactivity was 76,6 +/- 25,7% (r: 22-100%), been higher than 75% in six patients. Six patients were recipients of a second or third transplant. Immunosuppression consisted of quadruple therapy including induction with thymoglobuline. Five patients had delayed graft function, and one had primary non-function of the graft. One patient lost her graft due to chronic allograft nephropathy in the second year postransplantation. Six patients maintained a good renal function (serum creatinine 1,2 +/- 0,5 mg/dl, proteinuria 0,20 +/- 0,34 g/day). CONCLUSION: Renal transplantation in presence of a positive cross-match with historical serum and T lymphocytes and/or B lymphocytes, was followed by a satisfactory graft survival.

Adult↗
PubMed2006

[Chronological aggregation of subcutaneous mycosis in renal transplant recipients].

We present four cases of subcutaneous invasive mycosis in renal transplant recipients that happened in our Unit during a period of eight months. The Microbiology Department did not find any fungi when they studied possible reservoirs and vectors for transmission. We speculate about the reasons of this chronological aggregation. We discuss the treatment that we used for these infections.

Aged↗
PubMed2005

Longitudinal changes in insulin sensitivity and secretion from birth to age three years in small- and appropriate-for-gestational-age children.

AIMS/HYPOTHESIS: Insulin resistance and type 2 diabetes risk in human subjects who were small-for-gestational-age (SGA) at birth may be a consequence of rapid early postnatal weight gain. MATERIALS AND METHODS: We prospectively studied early changes in fasting insulin sensitivity and insulin secretion, assessed by a short intravenous glucose tolerance test that was conducted several times from birth to 3 years of age in 55 SGA (birthweight below fifth percentile) newborns and in 13 newborns with a birthweight appropriate for gestational age (AGA). RESULTS: Most SGA infants showed postnatal upward weight centile crossing and by 3 years were similar in size to AGA infants. SGA infants had lower pre-feed insulin levels at postnatal age 48 h than AGA infants (median 34.4 vs 59.7 pmol/l, p<0.05), but by the age of 3 years they had higher fasting insulin levels (median 38.9 vs 23.8 pmol/l, p<0.005), which were related to rate of weight gain between 0 and 3 years (r=0.47, p=0.0003). First-phase insulin secretion did not differ between SGA and AGA infants, but SGA infants had a lower glucose disposition index (beta cell compensation) (median 235 vs 501 min mmol(-1) l(-1), p=0.02), which persisted after allowing for postnatal weight gain (p=0.009). CONCLUSIONS/INTERPRETATION: SGA infants showed a marked transition from lower pre-feed insulin and increased insulin sensitivity at birth to insulin resistance over the first 3 years of life. This transition was related to rapid postnatal weight gain, which could indicate a propensity to central fat deposition. The additional observation of reduced compensatory beta cell secretion underlines the need for long-term surveillance of glucose homeostasis in all SGA subjects, whether or not they show postnatal catch-up growth.

Birth Weight↗
PubMed2004

[Post-transplant diabetes mellitus associated with acute hepatitis C virus infection in a renal transplant recipient].

There are some controversial reports about the pathogenic role of hepatitis C virus infection on diabetes mellitus in renal graft recipients. We report a case of a renal transplanted who developed diabetes mellitus post-transplantation during an acute hepatitis C virus infection. We discuss the multifactorial etiology of post-transplant diabetes mellitus, and the possible interaction between tacrolimus and an acute virus C infection on its pathogenesis.

Acute Disease↗
PubMed2003

The chemistry of precipitation, throughfall and stemflow in two holm oak (Quercus ilex L.) forests under a contrasted pollution environment in NE Spain.

Atmospheric deposition was studied through measurements of bulk deposition, throughfall and stemflow at two sites of contrasted exposure to pollution in the Montseny mountains (Northeastern Spain). To explore the contribution of local or distant sources at both sites, concentration data and precipitation amounts (log transformed) for both bulk deposition and net throughfall were fitted by linear regression. These models indicated the more important contribution of washout scavenging processes and dry deposition at the pollution exposed site. This is relevant in the context of Mediterranean holm oak forests: up to now, most of the studies have been conducted in protected remote sites and were little representative of the fluxes in forests close to industrial activity, traffic, agriculture and residential areas.

Air Pollutants↗
PubMed2003

Insulin gene VNTR genotype is associated with insulin sensitivity and secretion in infancy.

AIMS: We have previously demonstrated that insulin sensitivity and secretion at age 1 year was in part related to variation in weight and height gain during infancy. In order to determine whether genetic variation at the insulin gene could also influence these associations, we have studied the relationship between insulin gene variable number of tandem repeat (INS VNTR) genotypes, insulin secretion and early postnatal growth. METHODS: We assessed fasting and dynamic insulin secretion in 99 healthy infants at age 1 year, using a short intravenous glucose tolerance test (sIVGTT). Infants were genotyped at the -23 HphI locus, as a surrogate marker for INS VNTR allele classes I and III. Anthropometric data were recorded at birth and at 1 year. Data are shown as median (interquartile range). RESULTS: Fasting insulin levels were higher in III/III infants (n = 9) than in I/I infants [n = 55; 27.4 (17.6-75.6) pmol/l vs. 18.1 (10.3-25.2) pmol/l; P < 0.05]. Insulin secretion during the sIVGTT, as estimated by the serum insulin area under the curve, was also higher in III/III infants [2417 (891-4041) pmol min/l vs. 1208 (592-2284) pmol min/l; P < 0.05]. Fasting and postload plasma glucose levels were similar in both groups. Analysis of covariance showed that genotype differences in fasting insulin sensitivity and insulin secretion were independent of size at birth, postnatal growth velocity and current body mass index. CONCLUSIONS: Significant associations between INS VNTR genotype and both insulin sensitivity and secretion were apparent in infancy; these might interact with childhood appetite and nutrition to impact the development of childhood obesity and insulin resistance.

Analysis of Variance↗
PubMed2002

Nitrogen deposition in Mediterranean forests.

Atmospheric deposition of inorganic nitrogen was studied at two forested sites in the Montseny mountains (northeast Spain), peripheral to the Barcelona conurbation, and at a nearby lowland town, using bulk deposition, wet-only deposition, throughfall, and dry deposition inferred from branch-washes and surrogate surfaces (metacrylate plates). Bulk deposition inputs of ammonium and nitrate did not show significant temporal trends over a 16-year period. Bulk inputs of inorganic N were moderate, ranging from 6 to 10 kg N ha(-1) year(-1) depending on the time period considered and the degree of site exposure to polluted air masses from the Barcelona conurbation. Large dry-sedimented particles played a minor role, since wet-only inputs were virtually identical to bulk inputs. On the contrary, branch- and plate-washes indicated substantial dry inputs of N gases and small particles. Total atmospheric deposition was estimated at 15-22 kg N ha(-1) year(-1), most of it being retained within the studied broadleaved evergreen forests. Ecosystem N availability is thus likely to be increasing in these forests.

Air Pollutants↗
PubMed2001

Effects of oral administration of ibutamoren mesylate, a nonpeptide growth hormone secretagogue, on the growth hormone-insulin-like growth factor I axis in growth hormone-deficient children.

Ibutamoren mesylate (MK-0677), an orally active nonpeptide growth hormone (GH) secretagogue, stimulates GH release through a pituitary and hypothalamic receptor that is different from the GH-releasing hormone receptor. We evaluated the safety and tolerability and the GH-insulin-like growth factor (IGF) responses to two dosages of oral ibutamoren mesylate given to children with GH deficiency for 7 to 8 days. The patients, 18 prepubertal children (15 male, 3 female) with idiopathic GH deficiency, had a chronologic age of 10.6 +/- 0.8 years (mean +/- SD), bone age of 7.4 +/- 0.7 years, growth velocity < 10th percentile for age, height < 10th percentile for age, and a maximum GH response of < or = 10 microg/L to two different GH stimulation tests. The children were assigned as follows to one of three treatment groups with ibutamoren mesylate: 0.2 mg/kg per day for 7 days (days 1-7 or 8-14) and matching placebo for the alternate 7 days (groups I and II, respectively) or 0.8 mg/kg per day for 7 days (days 8-14, group III). On day 15 all patients received an 0.8-mg/kg dose of ibutamoren mesylate. Patients in groups I and II were studied first to assess safety at the low dose before advancement to the high dose. Hormonal profiles were evaluated on day -1 (baseline) and day 15, and the results were expressed as the change from baseline within each group. After administration of ibutamoren mesylate 0.8 mg/kg for 8 days (group III), the median increases (on day 15) from baseline were as follows: 3.8 microg/L (range, 0 to 34.3) for serum GH peak concentration (P = .001), 4.3 microg x h/L (range, 1.3 to 35.6) for the GH area under the concentration-time curve from time zero to 8 hours (AUC(0-8)) (P < .001), 12 microg/L (range, -4 to 116) for serum IGF-I (P = .01), and 0.4 microg/L (range, -0.9 to 1.5) for serum IGF-binding protein 3 (IGFBP-3) (P = .01). There was no change in serum prolactin, glucose, triiodothyronine, thyroxine, thyrotropin, peak serum cortisol, and insulin concentrations or 24-hour urinary free cortisol after administration of 0.8 mg/kg per day of ibutamoren mesylate for 8 days. We conclude that short-term administration of ibutamoren mesylate can increase GH, IGF-I, and IGFBP-3 levels in some children with GH deficiency. Thus this compound is applicable for testing its effect on growth velocity.

Administration, Oral↗
PubMed2001

Study of GH sensitivity in chilean patients with idiopathic short stature.

We hypothesized that some children with idiopathic short stature in Chile might bear heterozygous mutations of the GH receptor. We selected 26 patients (3 females, 23 males) from 112 patients who consulted for idiopathic short stature at the University of Chile. Their chronological age was 8.3 +/- 1.9, and bone age was 6.1 +/- 1.0 yr. Their height was -3.0 +/- 0.7 SDS; IGF-I, -1.2 +/- 1.1 SD; IGF binding protein 3, -0.7 +/- 2.0 SDS; and GH binding protein, 0.4 +/- 0.8 SDS. Patients were admitted, and blood samples were obtained every 20 min to determine GH concentrations overnight. Coding sequences and intron-exon boundaries of exons 2-10 of GH receptor gene were amplified by PCR and subsequently analyzed through single-strand conformational analysis. Mean serum GH concentration, over 12-h, was 0.20 +/- 0.08 nM; pulse amplitude, 0.40 +/- 0.15 nM; number of peaks, 5.8 +/-1.5 peaks/12 h; peak value of GH during the 12-h sampling, 1.03 +/- 0.53 nM; and area under the curve, 151.4 +/- 56.1 nM/12 h. There were positive correlations between mean GH vs. area under the curve (P < 0.001) and GH peak (P < 0.01). The single-strand conformational analysis of the GH receptor gene showed abnormal migration for exon 6 in 9 patients and for exon 10 in 9 patients, which (by sequence analysis) corresponded to 2 polymorphisms of the GH receptor gene: an A-to-G transition in third position of codon 168 in exon 6 and a C-to-A transversion in the first position of codon 526 in exon 10. We further sequenced all coding exons and intron-exon boundaries in the most affected patients (nos. 6, 9, 11, 14, 15, 16, and 23). This analysis revealed a C-to-T transition in codon 161 of exon 6 in patient 23, which results in an amino acid change (Arg to Cys) in an heterozygous form in the patient and his father. In conclusion, the results of our study suggest that, in Chilean patients with idiopathic short stature, GH receptor gene mutations are uncommon, although we cannot exclude mutations that were missed by single-strand conformational analysis or mutations within introns or in the promoter regions of the GH receptor gene.

Autoradiography↗