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J Soler

Publications and source records attributed to J Soler.

At least 19 recordsLinked to original sources
PubMed2000

Establishment of reference values for standard dose short synacthen test (250 microgram), low dose short synacthen test (1 microgram) and insulin tolerance test for assessment of the hypothalamo-pituitary-adrenal axis in normal subjects.

OBJECTIVE: To assess the integrity of the hypothalamo-pituitary-adrenal(HPA) axis, many authors have proposed the short synacthen test (ACTH1-24, Tetracosactrin) as a replacement for the insulin tolerance test (ITT). The aim of this study was to compare the plasma cortisol response obtained with both short synacthen tests (high dose (HDT, 250 microgram) and low dose (LDT, 1 microgram)) with the peak reached during the ITT in healthy volunteers, and to establish the plasma cortisol cut-off level in each test. SUBJECTS AND METHODS: Thirty healthy subjects (16 F, 14 M), mean age 34 years, underwent both short synacthen tests. Twenty healthy subjects, 15 of whom (11 F, nine M) belonged to the above group, mean age 30 years, underwent an ITT. Plasma cortisol was measured using a chemiluminiscence immunoassay. RESULTS: There were no differences between plasma cortisol 30 minutes after both short synacthen tests (HDT: 684 +/- 123, LDT: 669 +/- 119 nmol/l) and the peaks reached with the LDT (691 +/- 123 nmol/l) and the ITT (673 +/- 99 nmol/l). The only difference (P < 0.001) was found in the comparison of plasma cortisol peak reached with the HDT (802 +/- 142 nmol/l) with the other tests. Plasma cortisol levels obtained in the 5th percentile in each test were: at + 30 minutes: (HDT: 537, LDT: 489 nmol/l), peak: (HDT 649, LDT 498, ITT: 539 nmol/l). CONCLUSIONS: Comparison of the plasma cortisol response at + 30 minutes with both short ACTH tests and the peak in the insulin tolerance test did not reveal differences. Each test, for each time point and for each biochemical method, requires its own minimum threshold of normality to assess the hypothalamo-pituitary-adrenal axis.

Adult↗
PubMed2000

Effects of long-term treatment with GH in the bone mineral density of adults with hypopituitarism and GH deficiency and after discontinuation of GH replacement.

BACKGROUND: Only few previous studies have assessed the effects of long-term growth hormone (GH) replacement therapy on bone mineral density (BMD) in adult patients with GH deficiency. The aim of this study was to investigate the effects of long-term GH therapy on bone metabolism and BMD. MATERIAL AND METHODS: At the start of the study, 20 adults with GH deficiency were randomized to receive either GH, 0.25 IU x kg per week, or placebo. After 6 months, patients in the placebo group were switched to GH therapy, and they received GH for a further 18 months. Of the 20 patients, 14 were male and 6 female with GH deficiency of adult-onset. The mean age of the patients at the start of the study was 40.3+/-10.9 years and the duration of GH deficiency was 10.6+/-6.4 years. Patients deficient in pituitary hormones other than GH had been receiving stable replacement doses of appropriate hormones for at least 6 months before the start of the study. Rates of bone metabolism were assessed by measuring calcium, phosphate, alkaline phosphatase, calciuria, phosphaturia and osteocalcin. BMD was measured by dual X-ray absorptiometry. Body composition was calculated from measurements of bioelectrical impedance. RESULTS: Before GH treatment, BMD in the femoral neck was lower in patients than in controls. The rate of bone resorption markers increased significantly after 6 months and remained stable during the whole treatment period. BMD significantly increased in L2-L4 after 12 months of treatment with an increase of Z-score. The total BMD increase was 4.5+/-6.5%. BMD in the femoral neck increased after 12 months with an increase of Z-score after 18 months. The total increase was 10.4+/-18%. The total BMD increase was not different among patients with or without basal osteopenia. In both groups BMD in L2-L4 and in the femoral neck remained stable after 12 months without GH treatment. Sex, age, BMI and the time in which GH deficiency started, before or after the end of the peak of BMD, did not correlate with BMD. The BMD values and their response to GH treatment did not correlate with other associated deficiencies, and we did not find differences among BMD increase and GH dose, levels of insulin-growth factor-I, insulin growth factor binding protein-3, and parameters of body composition. CONCLUSIONS: The results of the study support previous ones that BMD is subnormal in adults with GH deficiency; that GH replacement therapy stimulates bone turnover with initial biochemical changes; and that in the long term, this stimulation results in a significant augmentation in BMD that continues to increase after 2 years and remains stable after 12 months of GH withdrawal.

Absorptiometry, Photon↗
PubMed2000

Linear correlation between beta-cell mass and body weight throughout the lifespan in Lewis rats: role of beta-cell hyperplasia and hypertrophy.

We determined the beta-cell replicative rate, beta-cell apoptosis, cross-sectional beta-cell area, and pancreatic beta-cell mass throughout the entire postweaning lifespan (months 1, 3, 7, 10, 15, and 20) of Lewis rats. Beta-cell replication was progressively reduced in the initial months of life but remained stable after month 7 (month 1, 0.99 +/- 0.10%; month 3, 0.24 +/- 0.04%; month 7, 0.12 +/- 0.02%; month 10, 0.14 +/- 0.02%; month 15, 0.10 +/- 0.03%; month 20, 0.13 +/- 0.03%; analysis of variance [ANOVA], P < 0.001). Beta-cell apoptosis was low and did not change significantly from month 1 to 20 of life. Cross-sectional area of individual beta-cells increased progressively in the initial months, remained stable from month 7 to 15, and increased again on month 20. The estimated number of beta-cells per pancreas, calculated as the ratio of total beta-cell mass to individual beta-cell mass, tripled from month 1 to 7 but did not change significantly thereafter. Beta-cell mass increased approximately 8 times from month 1 to 20 (month 1, 2.04 +/- 0.28 mg; month 20, 15.5 +/- 2.32 mg; ANOVA, P < 0.001) and showed a strong and significant linear correlation with body weight (r = 0.98, P < 0.001). In summary, we have shown that beta-cell replication was maintained throughout the lifespan in normal rats, clearly establishing that the beta-cell birth rate does not fall to 0, even in very old rats. Beta-cell mass increased throughout the lifespan, closely matching the increment in total body weight at any time point. This increment was selective for beta-cells, since the growth of the endocrine non-beta-cell mass was limited to the initial months of life. Both beta-cell hypertrophy and hyperplasia contributed to increased beta-cell mass in young animals, but only beta-cell hypertrophy was responsible for the increased beta-cell mass found in old animals. This study provides a global perspective for understanding the dynamics of beta-cell mass in young, adult, and aged animals.

Aging↗
PubMed2000

Bone mineral density in patients with type 1 diabetes mellitus.

Although osteopenia is often reported as a complication of type 1 diabetes mellitus, its frequency and severity remain unclear, and studies of bone mineral density in type 1 diabetics have yielded conflicting results. We measured bone mineral density at the lumbar spine and femoral neck in 88 Spanish adults with type 1 diabetes mellitus responsible for moderately severe complications. Mean age (+/- SD) was 28.9 +/- 8.8 years, and mean disease duration was 11.2 +/- 6.4 years. As compared to normal Spanish adults, bone mineral density was decreased in the patients at the lumbar spine (Z-score, -0.32 +/- 1.08; P < 0.001) but not at the femoral neck (Z-score, -0.21 +/- 1.03; P non-significant). The magnitude of bone loss in the diabetics was small (T-score, -0.38 +/- 1.13 at the lumbar spine and -0.37 +/- 1.08 at the femoral neck). Only three patients met WHO criteria for osteoporosis at one or both measurement sites. Patients with retinopathy (n = 37) had lower lumbar spine bone mineral density values than patients without retinopathy; however, this difference was no longer present after adjustment for age and disease duration. Bone mineral density values were similar in patients with (n = 13) and without microalbuminuria. Our findings suggest that bone loss is not a major problem in younger type 1 diabetics with short disease durations and no severe diabetic complications.

Absorptiometry, Photon↗
PubMed1999

[Insulin resistance and metabolic syndrome in first-degree relatives of patients with NIDDM].

BACKGROUND: Relatives of type 2 diabetes mellitus (DM2) patients present or can develop the plurimetabolic syndrome (MS). Insulin sensitivity determination could be useful to detect relatives with higher risk. PATIENTS AND METHODS: Insulin sensitivity (IS) and MS in 106 first degree relatives of DM2 and 52 control subjects, matched for age, sex and body mass index (BMI). Insulin sensitivity was evaluated by the HOMA method. Insulin sensitivity was classified as high, middle or low according to the percentiles 33 and 66 observed in the control group. MS was diagnosed if hyperglycemia, hypertension, hypertriglyceridemia and overweight (two or more) were present. RESULTS: Insulin sensitivity was lower in relatives (36.3 vs 51.8%; p = 0.0001). Relatives with lower insulin sensitivity (n = 56) have higher BMI (29.2 vs 25.6 kg/m2), higher systolic (128 vs 116 mmHg) and diastolic (80 vs 74) blood pressure, hyperglycemia (5.7 vs 5.1 mmol/l), hyperinsulinemia (116 vs 59 pmol/l) and hypertriglyceridemia (1.4 vs 1.0 mmol/l) when compared with the remainder relatives (n = 50). Age, sex, waist/hip ratio and cholesterol level were similar in both groups. 23 relatives have MS (20 of them with low insulin sensitivity, relative risk = 8.7; 95% confidence interval 2.4-31.6). In multiple logistic regression analysis, only age and IS have a significant value to predict the presence of MS. CONCLUSIONS: Relatives of DM2 are insulin-resistant and present a high prevalence of MS. Both insulin sensitivity and MS are highly correlated. Insulin sensitivity evaluation using a simple methodology like HOMA can be useful in the selection of relatives at higher risk of MS.

Adolescent↗
PubMed1999

[Chronic prescription of drugs for geriatric patients at an urban health center].

OBJECTIVE: To find the chronic prescription of medication in older people, associated variables and its quality. DESIGN: Observation, descriptive-crossover study. SETTING: Urban health district. PATIENTS: Sample stratified in age and sex groups of 385 people of 65 and over registered at the health centre and not in institutions. MEASUREMENTS AND MAIN RESULTS: Social and demographic data, self-perception of health and functional capacity were obtained through interview; and pathology and medication records, from the clinical records and authorized medication cards. 349 people, average age 73 (SD +/- 6.5), were interviewed. There were 210 women and 139 men. 12% perceived their health as bad/very bad. Barthel's index and the Lawton scale were disturbed in 13.8% and 30.4%, respectively. 93% suffered some chronic pathology (average 2.7). 81.4% habitually took medication (average 3.1). The most commonly consumed drugs belonged to the cardiovascular (32%), nervous system (21%) and digestive apparatus and metabolism (17%) groups. For the first group, the main drugs were ACEIs and diuretics; for the second, analgesics and neuroleptics; for the third, antacid and antiulcer drugs. 86% had high intrinsic value, the most prescribed drugs of those with low intrinsic value belonged to the antivaricose, cerebral and peripheral vasotherapy, and urological drugs groups. Multiple medications was related significantly to having more than two chronic pathologies (OR = 7.89, 95% CI 4.40-14.15) and self-perception of worse health (OR = 2.51, 95% CI 1.13-5.59). CONCLUSION: The elderly persons with a greater number of pathologies and perception of worse health took more medication. We thought that our quality of prescription was acceptable, although we should review the indications for neuroleptics and reduce prescription for medication of low therapeutic value.

Age Factors↗
PubMed1999

[Diabetes mellitus associated with the A3243G mutation of mitochondrial DNA. Apropos a case].

The mitochondrial A3243G mutation of the tRNA(Leu) has been described in pedigrees with maternally inherited diabetes mellitus and deafness. Ten diabetic patients with sensorineural deafness were studied. Polymerase chain reaction and enzyme restriction analysis with Apa I were performed. The mutation was found in heteroplasmy in only one patient (1/10). She was a 43-years-old woman with maternally inherited diabetes and deafness since she was 29. The association of sensorineural deafness and maternal inherited diabetes are the clues to suspect this subtype of diabetes.

Adult↗
PubMed1999

A double-blind, randomized, placebo-controlled trial of pindolol augmentation in depressive patients resistant to serotonin reuptake inhibitors. Grup de Recerca en Trastorns Afectius.

BACKGROUND: Pindolol has been reported to hasten the antidepressant action of selective serotonin reuptake inhibitors in open-label and placebo-controlled trials. Pilot studies also suggested that pindolol could augment the antidepressant response in unresponsive patients. We investigated whether the addition of pindolol can induce a rapid response in treatment-resistant patients. METHODS: After a single-blind lead-in placebo phase of 5 days to exclude placebo responders, 80 outpatients with major depression who did not respond to a minimum of 6 weeks of treatment with clomipramine hydrochloride, 150 mg/d; fluoxetine hydrochloride, 40 mg/d; fluvoxamine maleate, 200 mg/d; or paroxetine hydrochloride, 40 mg/d, were randomly assigned to additionally receive placebo (3 times daily) or pindolol (2.5 mg 3 times daily) for 10 days. The median number of ineffective treatments in the current episode was 2 (range, 1-4). Hamilton Rating Scale for Depression and Montgomery-Asberg Scale for Depression scores were used as primary measures of efficacy. RESULTS: At end point, the Hamilton and Montgomery-Asberg scores and change from baseline in Hamilton score were not significantly different in patients taking placebo or pindolol. The response rate was equal in both groups (12.5%). No differences in the clinical outcome were found when the various pretreatment subgroups were considered. At end point, the plasma concentration of pindolol was 9.9+/-5.1 ng/mL (mean +/- SD; n = 40). CONCLUSIONS: Although pindolol can accelerate the antidepressant action of selective serotonin reuptake inhibitors in previously untreated patients, it does not elicit a rapid clinical response in treatment-resistant patients within a 10-day period.

Adult↗
PubMed1999

Insulin regulation of leptin synthesis and secretion in humans: the model of myotonic dystrophy.

OBJECTIVE: Myotonic dystrophy (MyD) is a systemic disorder in which insulin resistance is well recognized. In the present study we have characterized plasma leptin levels in patients with MyD and in age, sex and body mass index (BMI) matched controls and assessed the influence of leptin on the clinical manifestations of MyD. DESIGN AND PATIENTS: Body composition, plasma leptin, fasting and post-oral glucose tolerance test insulin, IGF-I and IGFBP3 were studied in 34 MyD patients and 33 controls. MEASUREMENTS: Body composition was measured using a bioelectrical impedance analyzer, and circulating levels of insulin, leptin, IGF-I, IGFBP3 were measured by IRMA or RIA. Insulin sensitivity was modelled according to a homeostasis model assessment (HOMA) computer-solved model. RESULTS: Percentage body fat was higher in patients than in controls (25.6 +/- 2.28% vs 18.8 +/- 1.53%, P = 0.013). Insulin levels, both fasting and after oral glucose were higher in patients than in controls, and insulin sensitivity was lower in patients than in controls. Serum leptin was higher in patients than in controls (20.98 +/- 3.11 micrograms/l vs 10.4 +/- 1.31 micrograms/l, P = 0.004), and higher in women than in men, both in patients and in controls. In patients, leptin levels were correlated with age, BMI, fasting insulin, insulin area under curve and lower insulin sensitivity, whereas leptin levels were not correlated with body fat or other parameters of body composition. In controls, leptin levels were correlated with BMI and body fat. The results were evaluated using logistic regression models for each of the 2 populations. In the model of MyD, insulin resistance and age correctly identified higher leptin levels in relation to controls out of 87.88% of patients, and in the model of controls male sex with a negative correlation and BMI correctly identified their leptin levels out of 84.33% cases. CONCLUSIONS: These findings show that MyD provides a different model of leptin regulation in humans, and suggest that in MyD patients there are correlations between leptin and insulin resistance and age, irrespective of body fat. In contrast, leptin levels in controls, correlate with sex and BMI. The data on leptin in this population of patients can not be related aetiologically to the muscle disease itself.

Adolescent↗
PubMed1999

Chemical modification of NADP-isocitrate dehydrogenase from Cephalosporium acremonium evidence of essential histidine and lysine groups at the active site.

NADP-isocitrate dehydrogenase from Cephalosporium acremonium CW-19 has been inactivated by diethyl pyrocarbonate following a first-order process giving a second-order rate constant of 3.0 m-1. s-1 at pH 6.5 and 25 degrees C. The pH-inactivation rate data indicated the participation of a group with a pK value of 6.9. Quantifying the increase in absorbance at 240 nm showed that six histidine residues per subunit were modified during total inactivation, only one of which was essential for catalysis, and substrate protection analysis would seem to indicate its location at the substrate binding site. The enzyme was not inactivated by 5, 5'-dithiobis(2-nitrobenzoate), N-ethylmaleimide or iodoacetate, which would point to the absence of an essential reactive cysteine residue at the active site. Pyridoxal 5'-phosphate reversibly inactivated the enzyme at pH 7.7 and 5 degrees C, with enzyme activity declining to an equilibrium value within 15 min. The remaining activity depended on the modifier concentration up to about 2 mm. The kinetic analysis of inactivation and reactivation rate data is consistent with a reversible two-step inactivation mechanism with formation of a noncovalent enzyme-pyridoxal 5'-phosphate complex prior to Schiff base formation with a probable lysyl residue of the enzyme. The analysis of substrate protection shows the essential residue(s) to be at the active site of the enzyme and probably to be involved in catalysis.

Acremonium↗
PubMed1999

Severe short-bowel syndrome in children. Clinical experience.

INTRODUCTION: Innovative surgical and pharmacological therapeutic measures in short-bowel syndrome (SBS) are constantly changing the prognosis of this devastating condition. The aim of this paper is to present our most recent experience in the treatment of this disease, with particular emphasis on the impact of home parenteral nutrition (HPN) and the use of growth hormone (GH). METHODS: A group of 8 patients with severe SBS have been studied for the past 4 years. Intestinal length of less than 25% normal at the time of bowel resection was the criterion for inclusion in this study. RESULTS: Mean age at the time of diagnosis was 2 years (ranging from 1 day to 9 years). The etiology of the SBS was Hirschsprung's disease (n = 3), midgut volvulus (n = 2), gastroschisis (n = 1), omphalocele with ileal atresia and necrotizing enterocolitis (n = 1) and Crohn's disease (n = 1). Length of the residual bowel was 8 and 50 cm with ileocecal valve (ICV) preservation and 23, 27, 30, 50, 70, 100 cm without ICV. Sixty percent of the patients survived. Two patients died due to fulminant gram-negative sepsis and one due to cardiac malformation. Two patients are still on parenteral nutrition (PN) providing 30 and 60% of total calories. Human GH (0.3 U/kg/day) was used in two patients over a period of 28 days. In these patients, an increased tolerance to enteral feeding was observed. HPN was provided in 5 cases, allowing regular school attendance in 3 patients. In 3 cases, discontinuation of the PN was achieved at 24, 25 and 35 months respectively. CONCLUSIONS: Human GH can improve tolerance of enteral feeding. HPN has a beneficial effect on child behaviour. Intestinal transplantation must be considered when no other surgical or medical measures are available.

Child↗
PubMed1999

Blood volumes and renal function in overt and subclinical primary hypothyroidism.

INTRODUCTION: Thyroid dysfunction is associated with marked alterations in cardiovascular and renal functions. In hypothyroidism, myocardial contractility, cardiac output, and oxygen consumption are decreased, whereas peripheral resistance is increased. METHODS: We assessed blood volumes and effective renal plasma blood flow (ERPF) and glomerular filtration rate (GFR) in 17 patients with overt primary hypothyroidism and in 15 of these patients when in euthyroid state after substitutive therapy. We performed the same measurements in eight patients with subclinical hypothyroidism. RESULTS: In the hypothyroid state, the plasma volume measured by dilution of 125I-albumin (APV) was higher than the calculated plasma volume (CPV) from packed red cell mass, suggesting an extravascular escape of albumin. After substitutive therapy, the CPV showed a statistical increase (P < 0.05), whereas APV remained unchanged. Both ERPF and GFR increased after thyroxine therapy (p < 0.05). In the subclinical group, blood volumes and renal function were similar to those found in the other group of patients when in the euthyroid state. CONCLUSIONS: We conclude that in primary hypothyroidism, ERPF and GFR are low, but that these values improve with substitutive therapy. CPV is a better index of the current plasma volume than APV. The difference between these two parameters suggests that the escape of albumin into the extravascular space in primary hypothyroidism is terminated by treatment. There are no clear abnormalities either in blood volumes or in renal function in subclinical hypothyroidism.

Adolescent↗
PubMed1999

Tumor necrosis factor system activity is associated with insulin resistance and dyslipidemia in myotonic dystrophy.

Myotonic dystrophy (MyD) is a multisystem autosomal dominant disorder associated with progressive muscle wasting and weakness. The striking metabolic abnormality in MyD is insulin resistance. The mechanism by which target tissues are insensitive to insulin action remains uncertain. In a recent study, plasma soluble tumor necrosis factor receptor (sTNFR)2 levels were found to be associated with muscle tissue mass and insulin resistance. Given these associations, we speculated that disorders of the muscle cell membrane could lead simultaneously to insulin insensitivity and sTNFR2 leakage in MyD. To test this hypothesis, we measured the levels of circulating sTNFR1 and sTNFR2 and insulin resistance in MyD patients. We studied 22 MyD patients and 24 age-, BMI-, and fat mass-matched control subjects. Both MyD men and women showed higher plasma insulin levels in the presence of comparable glucose concentrations than did control subjects. sTNFR2, but not sTNFR1, levels were approximately 1.5-fold higher in MyD patients. In parallel with these findings, the fasting insulin resistance index (FIRI) was also higher in MyD patients. In fact, in the whole population, fasting insulin and FIRI strongly correlated with sTNFR2 in both men (r = 0.77 and r = 0.81, P<0.0001, respectively) and women (r = 0.67 and r = 0.64, P = 0.001, respectively). sTNFR2 levels were also associated with the insulin sensitivity index (S(I)), calculated from an oral glucose tolerance test (OGTT) according to the method by Cederholm and Wibell (r = -0.43, P = 0.006). We constructed a multiple linear regression to predict FIRI, with BMI, waist-to-hip ratio, and sTNFR2 as independent variables. In this model, both BMI (P = 0.0014) and sTNFR2 (P = 0.0048) levels contributed independently to 46% of the variance of FIRI. In another model, in which FIRI was substituted for S(I) from the OGTT, both BMI (P = 0.0001) and sTNFR2 (P = 0.04) levels contributed independently to 48% of the variance of S(I) from the OGTT. Plasma cholesterol and triglyceride concentrations were significantly increased in MyD patients. sTNFR1 and sTNFR2 levels were found to be strongly associated with plasma cholesterol, LDL cholesterol, and triglycerides. sTNFR1 and sTNFR2 also correlated with serum creatine kinase activity in MyD patients (r = 0.57, P = 0.006; r = 0.75, P<0.0001, respectively). In conclusion, here we describe, for the first time to our knowledge, a relationship between insulin action and plasma sTNFR2 concentration in MyD patients. We have also found increased concentrations of plasma triglycerides and cholesterol levels in parallel with sTNFR1 and sTNFR2 concentrations in MyD patients. We speculate that the latter associations are dependent on, and secondary to, increased tumor necrosis factor (TNF)-alpha action. Whether TNF action is implicated in the pathogenesis of MyD or is a simple marker of disease activity awaits further studies.

Adult↗
PubMed1999

Clinical presentation and early course of type 1 diabetes in patients with and without thyroid autoimmunity.

OBJECTIVE: To evaluate the prevalence of thyroid autoimmunity (TAI) in patients with recent-onset type 1 diabetes and to determine the influence of TAI on the clinical presentation and evolution of type 1 diabetes. RESEARCH DESIGN AND METHODS: We studied 111 newly diagnosed type 1 diabetes patients > 13 years old. The diagnosis of TAI was based on medical history and measurement of thyroid peroxidase (microsomal) antibodies (TPOAs). Clinical presentation of diabetes, beta-cell autoimmune markers (GADAs and 1A2As), and evolution of insulin-secretory reserves and metabolic control during the first 2 years of follow-up were analyzed. Differences between groups were evaluated by Student's t test or the chi 2 test. The influence of TAI on follow-up data was evaluated by multiple logistic regression analysis. RESULTS: TAI was present in 31 patients (14 TPOA+ patients with normal thyroid function, 12 TPOA+ patients with thyroid dysfunction, and 5 patients with previously diagnosed TAI). TAI was more prevalent in women than in men (43.7 vs. 15.9%, P = 0.001). beta-Cell autoimmunity was more prevalent in patients with TAI than in those without TAI (93.5 vs. 76.3%, P = 0.03). The evolution of insulin requirements, metabolic control, and insulin-secretory reserves was comparable in the two groups. CONCLUSIONS: TAI is present in many type 1 diabetes patients at the time of diagnosis and is associated with a high prevalence of thyroid dysfunction. The clinical presentation of diabetes and the evolution of metabolic control and insulin-secretory reserves are not influenced by the presence of TAI. Patients with type 1 diabetes should be screened for TAI at diagnosis.

Adolescent↗
PubMed1998

Binding characteristics of purified Escherichia coli K88ab fimbriae to guinea pig erythrocyte membrane.

The characteristics of the binding of biotinylated E. coli K88ab fimbriae to guinea pig erythrocyte membranes, as a possible model of the target host cell were studied. Binding showed sigmoidal dependence, with an apparent saturation at about 0.8 ng of fimbriae. Hill coefficient values (h) were about 2-2.4, which indicated that the receptor population showed positive cooperativity with at least three binding sites. Apparent binding constants to the first and third binding sites (1K3 and 3K3) were determined. Three K88ab binding proteins, of 67, 63 and 48 kDa, were identified on solubilized erythrocyte membranes and were recovered mainly in a detergent phase, suggesting a possible integral localization of the receptors.

Adhesins, Bacterial↗
PubMed1998

Functional characteristics of pyruvate transport in Phycomyces blakesleeanus.

A saturable and accumulative transport system for pyruvate has been detected in Phycomyces blakesleeanus NRRL 1555(-) mycelium. It was strongly inhibited by alpha-cyano-4-hydroxycinnamate. l-Lactate and acetate were competitive inhibitors of pyruvate transport. The initial pyruvate uptake velocity and accumulation ratio was dependent on the external pH. The Vmax of transport greatly decreased with increasing pH, whereas the affinity of the carrier for pyruvate was not affected. The pyruvate transport system mediated its homologous exchange, which was essentially pH independent, and efflux, which increased with increasing external pH. The uptake of pyruvate was energy dependent and was strongly inhibited by inhibitors of oxidative phosphorylation and of the formation of proton gradients. Glucose counteracted the inhibitory effect of the pyruvate transport produced by inhibitors of mitochondrial ATP synthesis. Our results are consistent with a pyruvate/proton cotransport in P. blakesleeanus probably driven by an electrochemical gradient of H+ generated by a plasma membrane H+-ATPase.

Acetates↗