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M Bex

Publications and source records attributed to M Bex.

At least 19 recordsLinked to original sources
PubMed2006

Levothyroxine replacement therapy after thyroid surgery.

INTRODUCTION AND AIM: New entities, such as 'subclinical' over- and undersubstitution, are easily diagnosed after thyroid surgery due to improved testing methods, and the incidence of thyroidectomy with lifelong hormone substitution is increasing. Thus, there is a need to review conventional replacement therapy after thyroid surgery. We investigated the adequacy of our thyroid hormone replacement therapy for three months after total-, subtotal-, and hemithyroidectomy using an upper reference limit of thyrotropin (TSH) of 4.6 mU/L. MATERIALS AND METHODS: Eighty-seven patients undergoing thyroidectomy for benign thyroid pathology participated. Levothyroxine (L-T4) treatment began five days after surgery. Preoperatively euthyroid patients received 150 microg L-T4 daily following total thyroidectomy, 100 microg L-T4 after subtotal thyroidectomy, and 50 microg L-T4 after hemithyroidectomy. Preoperatively hyperthyroid patients received 100 microg L-T4 following total thyroidectomy and 50 microg L-T4 following subtotal thyroidectomy. An average of six weeks after surgery, thyrotropin (TSH) was measured (reference limits 0.15-4.60 mU/L), and necessary dose adjustments were made. RESULTS: Of the patients who were preoperatively euthyroid, 45% with total thyroidectomy, 42% with subtotal thyroidectomy, and 17% with hemithyroidectomy required L-T4 dose adjustments. Of the patients who were preoperatively hyperthyroid, 60% of those with total thyroidectomy and all of those with subtotal thyroidectomy required L-T4 dose adjustments. CONCLUSIONS: To avoid over- and undersubstitution after thyroidectomy, an optimal replacement therapy dose is necessary. A small majority of our preoperatively euthyroid patients received adequate therapy. Endocrinological follow-up six weeks after surgery revealed the need for L-T4 dose adjustments, especially in preoperatively hyperthyroid patients. When the extent of resection was similar for hyperthyroid and euthyroid patients, the same initial dose of L-T4 was justified.

Adult↗
PubMed2004

One-year follow-up of patients with acromegaly treated with fixed or titrated doses of lanreotide Autogel.

OBJECTIVE: Somatostatin analogue treatment is first-line medical therapy for acromegaly. This study compared the efficacy and tolerability of titrated doses of the long-acting somatostatin analogue preparation lanreotide Autogel with fixed doses and with lanreotide prolonged release (PR) 30 mg microparticles. PATIENTS: Patients entering the initial study had received a diagnosis of active acromegaly within the previous 5 years. DESIGN: This open, comparative, multicentre study was a 1-year extension of a previous trial during which patients with acromegaly had switched from lanreotide PR 30 mg microparticles injected intramuscularly every 7, 10 or 14 days, for at least 3 months, to one of three fixed doses of lanreotide Autogel (120, 90, or 60 mg every 28 days, respectively). In this extension study, patients continued to receive 60, 90, or 120 mg of lanreotide Autogel by deep subcutaneous injection every 28 days for 1 year. Doses could be titrated at entry or after four or eight injections, according to the GH/IGF-I response (dose increased if GH > 2.5 micro g/l, or decreased if GH < 1 micro g/l with normal IGF-I). MEASUREMENTS: Mean +/- SEM GH and IGF-I concentrations were analysed and gallbladder echography performed at weeks 0, 16, 32, and 48. Acromegaly symptoms were recorded monthly and tolerance and side-effects were monitored throughout the study. RESULTS: In total, 130 patients entered this extension phase. After 1 year of treatment with titrated doses of lanreotide Autogel, mean GH (2.4 +/- 0.2 micro g/l) and IGF-I (287 +/- 12 micro g/l) concentrations were significantly lower than with lanreotide microparticles (GH, 2.8 +/- 0.2 micro g/l, P < 0.001; IGF-I, 332 +/- 15 micro g/l, P < 0.01) or with fixed-dose lanreotide Autogel (GH, 3.0 +/- 0.2 micro g/l, P < 0.001; IGF-I, 310 +/- 14 micro g/l, P = 0.02). GH hypersecretion was reduced to </= 2.5 micro g/l in 68% of patients with titrated-dose lanreotide Autogel compared with 49% with microparticles (P < 0.001) and 56% with fixed-dose lanreotide Autogel (P </= 0.005). In the 65 patients who did not require any dose titration, there was no substantial change in serum lanreotide concentration, GH or IGF-I levels over the 12-month study duration. Acromegaly was effectively controlled (GH </= 2.5 micro g/l and normalized IGF-I) in significantly more patients (43%) compared with microparticles (32%; P < 0.05). There was a trend for improved control of acromegalic symptoms with dose titration, whereas the incidence of gastrointestinal symptoms and local tolerance was similar with lanreotide Autogel and lanreotide microparticles. Gallbladder echographies showed new lithiasis in 8% of lanreotide Autogel patients. CONCLUSION: Dose titration of lanreotide Autogel improved GH and IGF-I control in patients with acromegaly beyond that achieved using fixed doses of lanreotide Autogel or lanreotide microparticles. Titrated long-term lanreotide Autogel treatment is well tolerated.

Acromegaly↗
PubMed2003

Oral administration of the growth hormone secretagogue NN703 in adult patients with growth hormone deficiency.

OBJECTIVE: Little is known of the usefulness of GH secretagogues (GHSs) in GH-deficient (GHD) adults. The objective of this study was to determine the number of responders to treatment with NN703 in GHD adults. DESIGN: A multicentre, randomized, double-blind, and placebo-controlled study. PATIENTS: Ninety-seven GHD adults were included. MEASUREMENTS: The GH response before and after 1 week of oral treatment with NN703 (n = 83) or placebo (n = 14) was determined. The first and last dose of NN703 was 3 mg/kg, whereas the dose of NN703 was 1.5 mg/kg/day during the 6 days between the first and last doses. Furthermore, all 97 patients received 1 micro g/kg GH-releasing hormone (GHRH) 3 weeks after the last dose of NN703. RESULTS: Serum GH peak and area under curve (AUC) values after the first NN703 administration were greater than those after placebo administration (P < 0.05). However, after correction for the lower body mass index (BMI) in the NN703 group, this difference lost statistical significance. After 1 week of therapy, GH peak and AUC values were similar following the final doses of NN703 and placebo. Serum peak and AUC values of other anterior pituitary hormones were similar between the NN703 and placebo groups both after the first and last administration of study drug. Nine of the 83 patients (11%) responded with a serum peak GH concentration >or= 5 micro g/l after the first and/or last NN703 administration, whereas no patient responded after placebo administration. Serum IGF-I was unaffected by 1-week NN703 treatment, whereas serum IGFBP-3 was increased (P < 0.05 vs. placebo) also after correction for BMI. Mean serum peak GH concentration after GHRH administration was 2.1 micro g/l (+/-0.3, SEM), which was higher than that after the first NN703 administration (1.32 +/- 0.3, P < 0.05). CONCLUSION: NN703 administration was generally well tolerated. Eleven per cent of the GHD adult patients responded with a peak GH response >or= 5 micro g/l after the first and/or last administration of oral NN703. Although a majority of GHD adults will not respond to NN703, the present results suggest that oral NN703 treatment could be useful in some adult patients with moderately severe GHD. These patients may be identified by a test dose of GHS.

Administration, Oral↗
PubMed2001

Effects of l-thyroxine administration, TSH-receptor antibodies and smoking on the risk of recurrence in Graves' hyperthyroidism treated with antithyroid drugs: a double-blind prospective randomized study.

OBJECTIVE: In Graves' hyperthyroidism treated with antithyroid drugs (ATD), the overall relapse rate reaches 30-50% following ATD discontinuation. Conflicting results have previously been reported with regard to the usefulness of combining ATD with thyroxine (l-T4), and thereafter maintaining l-T4 treatment after ATD withdrawal. Also, clinicians are in search of useful parameters to predict the risk of a recurrence of hyperthyroidism after ATD treatment. DESIGN: Eighty-two consecutive patients (70 women and 12 men; mean age 36 years) with a first episode of Graves' hyperthyroidism were investigated prospectively; they were treated with ATD for a total of 15 months, combined with l-T4 (for at least 12 months) after they had reached euthyroidism, with the aim of maintaining serum TSH below 2.5 mU/l during the combined therapy. Following ATD discontinuation, the patients were randomly assigned (double-blind placebo-controlled trial) to taking 100 microg/day l-T4 (vs placebo) for an additional year. METHODS: The following determinations were carried out at initial diagnosis: serum total T4 and tri-iodothyronine (T3), free T4 and T3, TSH, TSH-receptor antibodies (TSHR-Ab), thyroid scintigraphy and echography. During ATD treatment, serum free T4 and T3 and TSH concentrations were recorded after 1 (optional), 2, 4, 6, 9, 12 and 15 months, and echography at the end of ATD treatment. During the randomized trial, serum free T4 and T3 and TSH concentrations were checked every 3 months (or until a recurrence). TSHR-Ab titers were measured at initial diagnosis, after 6 months with ATD, and at the end of ATD treatment. RESULTS: l-T4 administration, both during and after ATD treatment, did not improve the final outcome and recurrence rates were similar in placebo and l-T4-treated patients (30%). Two parameters were identified that might be useful to help predict recurrence risks after ATD: (i) positive TSHR-Ab (at the end of ATD treatment) was significantly associated with a greatly increased recurrence risk; and (ii) despite the relatively small number of patients who were smokers, regular cigarette smoking was shown, for the first time, to be significantly associated with an increased recurrence risk. Also, the deleterious effect of smoking was shown to manifest its impact independently of TSHR-Ab titers at the end of ATD treatment. Thus, compared with the overall 30% recurrence risk, non-smoking patients with a negative TSHR-Ab (at the end of ATD) had a lower (18%) recurrence risk; smoking patients with negative TSHR-Ab (at the end of ATD) had a 57% recurrence risk; non-smoking patients with positive TSHR-Ab (at the end of ATD) had a high (86%) recurrence risk; the recurrence risk was 100% in those few patients who both smoked and maintained a positive TSHR-Ab at the end of ATD treatment. CONCLUSIONS: The present study confirmed that l-T4 administration during and after ATD withdrawal did not improve remission rate. Two factors, namely positive TSHR-Ab at the end of ATD treatment and regular smoking habits may represent clinically useful (albeit not absolute) predictors of the risk of recurrence in patients with Graves' hyperthyroidism treated with ATD. However, due to the relatively small number of smoking patients in the present cohort, this conclusion needs to be confirmed by a larger study.

Adult↗
PubMed2000

Primary role of the HLA class II DRB1*0301 allele in Graves disease.

The association of the Graves disease (GD) with HLA DR3 and DQA1*0501 in Caucasians has been described previously. From these studies it could not be determined whether one specific locus was primarily involved. Using a case-control study design, we have examined the role of HLA class II gene polymorphisms in the predisposition for GD in a group of Belgian subjects. We demonstrated that both DRB1*0301 and DQA1*0501 alleles conferred significant susceptibility in the DRB1*0301-DQA1*0501 haplotype. The DRB1*0301 allele was the primary susceptibility allele for GD, however, because the susceptibility provided by DQA1*0501 was most likely due to it being in linkage disequilibrium with DRB1*0301. The DRB1*0701/x and DQA1*0201/x genotypes and the DRB1*0701-DQA1*0201 haplotype provided protection with an equal RR of 0.29. Predictive value calculations showed that testing for DRB1*0301 gave the highest positive predictive value for GD in females and males. This was, however, 10 times higher in females and predicted a 3.63% risk for a random female to develop GD.

Alleles↗
PubMed2000

Slow-release lanreotide in the treatment of acromegaly: a study in 66 patients.

OBJECTIVE: Slow-release (SR) lanreotide is a long-acting somatostatin analog that has been developed in order to overcome the inconvenience of multiple daily subcutaneous injections of octreotide, required for metabolic control in acromegaly. Lanreotide SR has been found to be well tolerated and effective in reducing GH and IGF-I levels but clinical data are still limited compared with those with subcutaneous octreotide treatment. DESIGN: Sixty-six unselected patients with active acromegaly were therefore evaluated in a multi-center, prospective, open label study. Lanreotide SR was given at a dose of 30mg intramuscular every 7-14 days. METHODS: At baseline and after 2, 4, 8, 12, 24, 36 and 48 weeks patients underwent a clinical examination with assessment of acromegaly related symptoms, and blood was sampled for serum GH, IGF-I, prolactin, glycosylated hemoglobin, fasting glucose, hematology, kidney function and liver function tests. Biliary ultrasonography and pituitary magnetic resonance imaging were performed at baseline and after one year. RESULTS: Treatment resulted in a significant improvement in the symptom score from 2.69+/-0.27 to 1.06+/-0.17 (P<0.0001). Serum IGF-I levels fell from 699+/-38microg/l at baseline to 399+/-26microg/l (P<0.0001, n=60) after one month, after which levels remained stable: 480+/-37microg/l after 6 months (n=54) and 363+/-32microg/l after one year (n=46). GH levels dropped from 13.8+/-3.2microg/l to 4.3+/-0.7microg/l after one month (P<0.0001, n=60) and remained stable thereafter: 3.9+/-0.4microg/l (n=54) after 6 months and 3.5+/-1.1microg/l after one year (n=46). Twenty-nine out of 66 patients (44%) attained a normal age-corrected IGF-I level and 30 patients (45%) attained a GH level below 2.5microg/l. Pituitary adenoma shrinkage of at least 25% was found in 5 of 14 patients (36%) after one year. Side effects were mainly transient gastrointestinal symptoms and pain at the injection site, resulting in drug discontinuation in only 6 patients (9%). Two patients developed new gall stones. No difference was found between subcutaneous octreotide and lanreotide SR in efficacy and almost all patients preferred the easier dose administration of lanreotide SR. CONCLUSIONS: Long-term treatment of acromegaly with SR-lanreotide is effective in controlling GH and IGF-I levels and symptoms and is well tolerated in the majority of patients. Compared with subcutaneous octreotide, lanreotide SR considerably improves patient's acceptance of therapy while having the same overall efficacy.

Acromegaly↗
PubMed1999

Aromatase deficiency caused by a novel P450arom gene mutation: impact of absent estrogen production on serum gonadotropin concentration in a boy.

We identified a new point mutation in the CYP19 gene responsible for aromatase (P450arom) deficiency in a 46,XY male infant with unremarkable clinical findings at birth. This boy is homozygote for a 1-bp (C) deletion in exon 5 of the aromatase gene causing a frame-shift mutation. The frame-shift results in a prematurely terminated protein that is inactive due to the absence of the functional regions of the enzyme. Aromatase deficiency was suspected prenatally because of the severe virilization of the mother during the early pregnancy, and the diagnosis was confirmed shortly after birth. Four weeks after birth, the baby boy showed extremely low levels of serum estrogens, but had a normal level of serum free testosterone; in comparison with the high serum concentration of androstenedione at birth, a striking decrease occurred by 4 weeks postnatally. We previously reported elevated basal and stimulated FSH levels in a female infant with aromatase deficiency in the first year of life. In contrast, in the male infant, basal FSH and peak FSH levels after standard GnRH stimulation tests were normal. This finding suggests that the contribution of estrogen to the hypothalamic-pituitary gonadotropin-gonadal feedback mechanism is different in boys and girls during infancy and early childhood. In normal girls, serum estradiol concentrations strongly correlate with circulating inhibin levels, and thus, low inhibin levels may contribute to the striking elevation of FSH in young girls with aromatase deficiency. In contrast, estradiol levels are physiologically about a 7-fold lower in boys than in girls, and serum inhibin levels remain elevated even though levels of FSH, LH, and testosterone are decreased.

Androstenedione↗
PubMed1998

Occult ectopic ACTH secretion due to recurrent lung carcinoid: long-term control of hypercortisolism by continuous subcutaneous infusion of octreotide.

We report on a woman with clinical Cushing's syndrome confirmed by biochemical data. The Cushing's syndrome was shown to be ACTH dependent and inferior petrosal sinus sampling pointed to an ectopic source. After resection of a lung carcinoid a well documented remission of Cushing's syndrome was obtained. At recurrence of Cushing's syndrome 18 months later the ACTH source could not be located despite extensive diagnostic procedures. Clinical and biochemical control of hypercortisolism was achieved by continuous subcutaneous infusion of octreotide. During a brief interruption of treatment recurrence of clinical and biochemical signs and symptoms of Cushing's syndrome were demonstrated. We conclude that in this case of occult ectopic ACTH secretion, presumably due to recurrent lung carcinoid, continuous subcutaneous infusion therapy with octreotide resulted in clinical and metabolic control of Cushing's syndrome for 8 years. In addition excellent tumour growth control was achieved as repeated searches for tumour recurrence or metastasis remained negative.

ACTH Syndrome, Ectopic↗
PubMed1998

Serum parathyroid hormone and calcium during the first days after resection of a parathyroid adenoma.

Serum parathyroid hormone, calcium and phosphate were daily monitored in 12, 30 and 30 patients respectively during the early postoperative period after removal of a solitary parathyroid adenoma. In all patients PTH concentration dropped to very low values on the first postoperative day, whereafter a rapid recovery began. So the first day is the best time to evaluate the results of the intervention. Hypocalcemia was most frequent on the third day. After ten days 26 patients showed a normal calcemia, while 4 patients still had a mild hypocalcemia (8-8.8 mg/dl). These data may guide management of patients after parathyroid surgery.

Adenoma↗
PubMed1995

Increased and decreased relative risk for non-insulin-dependent diabetes mellitus conferred by HLA class II and by CD4 alleles.

Non-insulin-dependent diabetes mellitus has been recognized to be heterogeneous in etiology, with multiple subgroups. Several genes or chromosomal regions have been implicated in the development of the disease. In this study the association of HLA class II alleles and genotypes and the association of CD4 and CD3 polymorphisms were assessed in a large number of Belgian non-insulin-dependent diabetes mellitus patients. Furthermore, the importance of the DQ alpha 1Arg52/DQ alpha 1Arg52 and the DQ beta 1Asp57/DQ beta 1Asp57 genotypes and the combination of both genotypes were examined. Our results show that in the HLA class II genes only the DQ alpha 1Arg52+/DQ alpha 1Arg52+ genotype was significantly associated with non-insulin-dependent diabetes mellitus compared with controls (p = 0.011, RR = 2.02). We also observed that the frequency of the CD4*A4/*A8 genotype and the CD4*A7 allele was significantly increased and decreased respectively in non-insulin-dependent diabetes mellitus patients as compared with the controls (p = 0.018, RR = 2.16 and p = 0.0003, RR = 0.49 respectively). These results therefore suggest that HLA class II and CD4 genes might independently contribute to the susceptibility for non-insulin-dependent diabetes mellitus and that these alleles and genotypes might identify subgroups of patients with different susceptibilities.

Adult↗
PubMed1995

Influence of age, sex, and insulin on osteoblast function: osteoblast dysfunction in diabetes mellitus.

The osteoblast function was evaluated in normal and diabetic children and adults by measurements of the serum concentration of the carboxy-terminal extension peptide of procollagen (PICP), total and skeletal alkaline phosphatase (ALP), and osteocalcin. Moreover, the osteoblast-stimulating growth factor, insulin-like growth factor I (IGF-I), was measured in the same samples. In normal children (n = 420; age, 5-20 yr), a marked pubertal increase of serum IGF-I (peak values at age 14-16 yr in both sexes), osteocalcin, and total and skeletal ALP (peak values earlier in girls than in boys) and a small increase in PICP were observed. All osteoblast markers and IGF-I were markedly lower in normal adults (n = 229; age, 21-69 yr) than in children. All osteoblast parameters showed a high degree of correlation (P < 0.001) with each other. In adolescents (n = 104) treated for insulin-dependent diabetes mellitus (IDDM), serum IGF-I (-19%), osteocalcin (-28%), and skeletal ALP (-28%) were markedly decreased, whereas total ALP was significantly increased (29%), and serum PICP remained normal. In adult IDDM (n = 125), both serum IGF-I (-41%) and osteocalcin (-24%) were decreased, but skeletal ALP and PICP remained normal. A similar abnormality in serum IGF-I and osteocalcin was observed in white (n = 61) and Pima Indian (n = 16) non-IDDM patients. The concentration of skeletal ALP was highly significantly correlated (r > or = 0.9) with total ALP in both normal and diabetic subjects, but the slope of the regression was significantly different, indicating the presence of other, probably intestinal, ALP in all types of diabetes. In conclusion, the osteoblast function is significantly decreased in diabetic patients, which can best be characterized as a maturation defect, since the early osteoblast marker, PICP, remained normal in all types of diabetes, whereas a later marker, skeletal ALP, is frankly abnormal only in diabetic children. The most mature osteoblast marker, osteocalcin, is decreased in all types of diabetes irrespective of age.

Adolescent↗
PubMed1994

Association of particular HLA class II alleles, haplotypes and genotypes with susceptibility to IDDM in the Belgian population.

Using a highly discriminatory DNA typing technique, based on the polymerase chain reaction and reverse dot blot hybridization, more refined results were obtained on the association of particular HLA class II alleles, haplotypes and genotypes with insulin-dependent diabetes mellitus in the Belgian population. The previously reported predisposing effect for the DRB1*0301 encoded DR3 serologic specificity was confirmed and could be assigned to the DRB3*0200 encoded DR52b serologic specificity. A second high risk haplotype, DRB1*0401-DQB1*0302 encoding the DR4-DQ8 serologic specificity, accounted for increased susceptibility both in the total insulin-dependent diabetic population and among DR4-positive patients. Moreover, we found that these DR4 associated DRB1 and DQB1 alleles act as independent risk factors. A possible role for the DPB1 locus can be rejected since the observed predisposing effect for DPB1*0202 probably occurred due to linkage disequilibrium of this allele with DRB1*0301. Particular extended haplotypes accounted for the decreased relative risk observed for the DR2, DR11 and DR13 serologic specificities. The highest relative risk was observed for those DQA1/DQB1 genotypes, allowing for the formation of 4SS (DQ alpha Arg52+/DQ beta Asp57-) heterodimers.

Adolescent↗
PubMed1994

Improved risk assessment for insulin-dependent diabetes mellitus by analysis of amino acids in HLA-DQ and DRB1 loci.

Polymorphisms in HLA class II genes have been shown to contribute to susceptibility or protection against insulin-dependent diabetes mellitus (IDDM). In the present study the role of HLA class II haplotypes and the role of DQ alpha Arg52, DQ beta Asp57 and of polymorphic amino acids, located in the antigen-binding groove and the CD4-binding domain of the DR beta 1 chain, were studied in 210 unrelated Caucasian IDDM patients and 205 controls. The results showed that the genotype homozygous for DR beta 1Lys71+, which is in linkage disequilibrium with DQ alpha 1Arg52+ provided a major risk (relative risk, RR = 15.46) for IDDM and that combination of DR beta 1Lys71+/+ with homozygosity for DQ beta qAsp57-/- of the DQ beta 1 chain significantly increased the RR for developing IDDM (RR = 20.41). The DQ alpha 1Arg52(-)-DQ beta 1Asp57+ haplotype in cis or trans position conferred the highest protection against IDDM (RR = 0.08). Our findings confirm that protection against IDDM is provided by HLA-DQ loci but that susceptibility for IDDM is provided by both HLA-DRB1 and DQB1 loci. Our results also provide a new and more specific approach to determine the risk of any random Caucasian individual to develop IDDM. Indeed, increased susceptibility or protection against IDDM can be determined by the rapid and simple typing of DR beta 1Lys71, DQ alpha 1Arg52 and DQ beta 1Asp57 in a random person.

Adolescent↗
PubMed1994

Erythrocyte cation transport systems in insulin-dependent diabetics: correlation with prorenin and albuminuria.

The relationship between erythrocyte cation transport systems, plasma prorenin and albuminuria was examined in patients with insulin-dependent diabetes mellitus (IDDM). Different measurements of erythrocyte transport systems were obtained in patients with IDDM: Na+/Li+ countertransport; Na+/K+ cotransport and Na+/K+ ATPase pump activity. In single regression analysis the erythrocyte Na+/Li+ countertransport was positively related to the plasma prorenin level. In multiple regression analysis the erythrocyte Na+/Li+ countertransport activity was independently related to plasma prorenin, albuminuria and age. Our data in patients with IDDM show that an elevated erythrocyte Na+/Li+ countertransport is accompanied by a higher plasma prorenin level and albuminuria.

Adult↗
PubMed1993

The measurement of fecal thyroxine in the diagnosis of thyrotoxicosis factitia.

Two patients with prolonged thyrotoxicosis are presented with low radioiodide uptake, low-normal serum thyroglobulin concentrations, and low iodide content of the neck on x-ray fluorescence studies. The surreptitious intake of thyroid hormone was directly proven by a high fecal concentration of T4 (12.38 and 23.99 nmol/g) compared with low concentrations in healthy subjects (1.03 +/- 0.64 nmol/g; mean +/- SD, n = 6) and in patients with hyperthyroidism due to Graves' disease (1.93 +/- 1.86; n = 8). Fecal thyroid hormone measurement may help to provide formal proof of factitious thyrotoxicosis.

Adult↗
PubMed1993

Erythrocyte cation transport systems and membrane lipids in insulin-dependent diabetes.

The relationship between erythrocyte cation transport systems and membrane and plasma lipids was examined in normal men and patients with insulin-dependent diabetes mellitus (IDDM). Different measurements of erythrocyte transport systems were obtained in patients with IDDM and in age- and weight-matched healthy men: Na+:Li+ countertransport activity or Li(+)-stimulated Na+ efflux, Na+:K+ cotransport activity or bumetanide-sensitive Na+ efflux, Na+:K+ pump activity or ouabain-sensitive Na+ efflux, and the ouabain- and bumetanide-resistant Na+ and K+ fluxes or the ground membrane permeability for Na+ and K+ as well as the intraerythrocyte Na+, K+, and Mg2+ concentrations. Plasma cholesterol, triglycerides, phospholipids, low- and high- density lipoprotein cholesterol, and erythrocyte membrane cholesterol and phospholipid content were obtained from the fasting subjects. The patients with IDDM had an elevated (P < .05 or less) erythrocyte Na+:Li+ countertransport activity, ground membrane leak for K+, intraerythrocyte K+ concentration, and erythrocyte membrane cholesterol content, but a lower red blood cell phospholipid content. In single regression analysis, the erythrocyte Na+:Li+ countertransport, Na+:K+ cotransport, and Na+:K+ pump activity and ground membrane leak for Na+ and K+ were inversely related to the red blood cell membrane lipid content. Our data in patients with IDDM show that a decreased erythrocyte membrane lipid content was accompanied by a higher erythrocyte Na+:Li+ countertransport, Na+:K+ cotransport, and Na+:K+ pump activity.

Adult↗