Complement functional tests for monitoring eculizumab treatment in patients with atypical hemolytic uremic syndrome

BACKGROUND

Atypical hemolytic uremic syndrome (aHUS) is a thrombotic microangiopathy characterized by hemolysis, platelet consumption, and renal injury. Eculizumab, a mAb that blocks complement activity, has been successfully used in aHUS.

OBJECTIVES

To optimize eculizumab therapy in aHUS patients by monitoring complement functional tests and markers of disease activity.

PATIENTS/METHODS

We studied 18 patients with aHUS (10 males; eight females; age range, 2-40 years) treated with eculizumab to induce and/or maintain disease remission. Patients were followed up for a cumulative observation period of 160 months, during which blood samples were obtained at various time intervals to measure complement activity (Wieslab for the classical, alternative and mannose-binding lectin complement pathways) and the parameters of disease activity (haptoglobin and lactate dehydrogenase serum levels, and platelet count). The intravenous eculizumab doses of 12-33 mg kg(-1) were initially administered every week, with the interval between doses being gradually extended to 2 weeks, 3 weeks and 4 weeks on the basis of strict laboratory and clinical control.

RESULTS

Complement activity was normal before eculizumab treatment, regardless of the state of the disease (activity or remission). It was completely suppressed 1 week, 2 weeks and 3 weeks after the last eculizumab infusion (mean values ± standard deviation: 1% ± 1% to 3% ± 5% for both the classical and alternative pathways; P = 0.0001 vs. baseline), and partially suppressed after 4 weeks (22% ± 26% and 16% ± 27%; P = 0.0001 vs. baseline). The increase in the time interval between eculizumab infusions did not change disease activity markers.

CONCLUSIONS

Monitoring complement tests can allow a safe reduction in the frequency of eculizumab administration in aHUS while keeping the disease in remission.

Transition from pediatric to adult care. eight years after the transition from pediatric to adult diabetes care: metabolic control, complications and associated diseases

BACKGROUND

Transition from pediatric to adult care is a critical process in the life of patients with diabetes.

AIM

Primary aim of the study was to compare the metabolic control between pediatric care and adult care at least 5 years in a group of patients with type 1 diabetes mellitus (T1DM). Secondary aim was to evaluate the presence of complications, associated diseases and psychological-psychiatric disorders.

SUBJECTS AND METHODS

We obtained data from 73 % (69/94) patients (current mean age 34 years) transferred to local adult centers between 1985 and 2005 at a mean age of 23.8 years. Data were collected for HbA1c, diabetic complications and associated diseases.

RESULTS

Mean HbA1c did not change during the pediatric, transition and adult period [8.4 ± 1.8 % (68 ± 18 mmol/mol), 8.3 ± 1.4 % (67 ± 15 mmol/mol) and 8.4 ± 1.3 % (68 ± 14 mmol/mol), respectively]. 13 patients dropped out, after 2-12 years since transition, and their HbA1c mean value at transition was 10.4 %. After a mean of 25.9 years of disease, 35/69 patients (50.7 %) showed retinopathy, and 12/69 patients (17.3 %) nephropathy. Thyroid diseases were the most frequent associated diseases (18.3 %), followed by depression (11.2 %) and benign neoplasms (9.8 %). Drug or alcohol addictions were present in four cases (5.6 %).

CONCLUSIONS

After a mean follow-up of 8 years metabolic control after transition did not change significantly in patients constantly attending to adult care centre. Patients with diabetes onset between 20 and 40 years ago were free from complications in 50 % of cases when considering retinopathy and in more than 80 % considering nephropathy. Thyroid problems were the most common associated diseases. Poor metabolic control at transition is associated with higher risk of drop-out and psychosocial morbidity.

A controlled, class-based multicomponent intervention to promote healthy lifestyle and to reduce the burden of childhood obesity

BACKGROUND

Overweight and obesity prevention in childhood and adolescence represent a priority for public health; school is a privileged place for health promotion interventions.

OBJECTIVES

The study aimed to test the effectiveness of a multicomponent 5-month intervention on the habits of primary school children, making the families aware of the importance of healthy choices.

METHODS

Two hundred nine children attending the fourth class of primary school, divided into interventional (n = 103) and control arm (n = 106) were included in the study. In the intervention group, parents and teachers received more intense lifestyle counseling, associated with weekly motivational telephone calls to families to motivate further their lifestyle changes. Standard deviation score (SDS) body mass index (BMI) was the primary outcome measure; on open-air games and TV watching were secondary outcomes.

RESULTS

At baseline, no differences were observed between groups. At 8-month follow-up, mean SDS BMI had decreased by 0.06 units in the intervention arm and increased by 0.12 in controls (time × treatment anova, P < 0.002). Outdoor activities increased from 6.23 h week(-1) to 9.93 in the intervention group (P < 0.001), not in controls. This change was associated differences in TV watching from baseline (intervention, -0.96 h week(-1); P = 0.037; controls, +1.33 h week(-1); P = 0.031).

CONCLUSION

A multicomponent school-based intervention addressing the needs of children, teachers and families produced a significant and favourable short-term effect on overweight/obese schoolchildren.

Younger age at diagnosis of type 1 diabetes mellitus in children of immigrated families born in Italy

The aim of this study was to evaluate the age of immigrants' children at diagnosis of Type 1 diabetes (T1DM) according to their country of birth. Immigration from developing countries to a westernised area causes rapid changes in the environmental conditions, and we investigated whether the location of birth, either inside or outside Italy, is associated with age at diagnosis of diabetes. Out of a prevalent hospital-based cohort of 5718 T1DM children cared for in 2002 in 47 Italian Pediatric Diabetes Units, we recruited 195 children (M: 97) of immigrants from developing countries--119 were born in Italy and 76 outside the European Union. Children with only one immigrant parent (no. 42) were also included. Age at diagnosis of T1DM, and other variables were compared with those of Italian children. Children of immigrated families born in Italy developed T1DM at a median age of 4.0 yr (IQR 2.2-6.9), whereas those born in developing countries and that had immigrated to Italy after birth developed T1DM at a median age of 7.9 yr (IQR 5.1-10.7, p < 0.001). Among the children born in Italy, 77 had parents who were both immigrants and the children's median age at diagnosis was 3.8 yr (IQR 2.1-6.3); 42 had only one immigrant parent and, when it was the father (no. = 23), median age was even younger (2.9 yr, IQR 2.0-8.2). Ten children had immigrated in their first yr of life and their median age was 9.1 yr (IQR 5.0-10.6). The median age of the Italian children was 6.6 yr (IQR 3.6-9.5). Results show that the outbreak of T1DM is earlier in immigrants' children born in Italy than in original countries.

Lymphocyte dysmetabolism: an immunocytochemical comparative approach in IDDM and control subjects

We have investigated by immuno-electron microscopy the presence of phosphotyrosine in cells as a whole and in different cell districts (nucleus, cytoplasm, plasma membrane, and mitochondria) in peripheral blood lymphocytes of IDDM (insulin-dependent diabetes mellitus) patients and age-matched controls. Immuno-gold particle density was highest in mitochondria and decreased in cytoplasm, nucleus and plasma membrane. The time dependence of phosphotyrosine labelling after cell isolation was very strong in all subcellular populations, with a fall in immunogold staining after 30 min. Staining levels at zero time were similar in controls and IDDM patients; the loss of phosphotyrosine labelling was much stronger in controls, except in the plasma membrane. Plasma membrane NADH oxidoreductase activity, studied using cytosolic NADH as substrate and assayed with DCIP as acceptor, was significantly increased in IDDM patients, suggesting a response to a deficient mitochondrial energetic activity. The fact that NADH oxidoreductase is a growth factor related to tyrosine phosphorylation pathways raises intriguing questions on the cellular derangement occurring in peripheral lymphocytes in IDDM, although the relationships among the immunocytochemical and biochemical changes is still obscure.

Diabetic retinopathy in childhood: long-term follow-up by fluorescein angiography beginning in the first months of disease

BACKGROUND

Little is known about minimal retinal lesions occurring in the first months of disease in children with type 1 diabetes mellitus (DM).

OBJECTIVE

To detect any early retinal change and to evaluate its progression in children diagnosed with type 1 DM.

PATIENTS

From 1979 to 1997 we examined by fluorescein angiography at diagnosis or within 15 months from the onset of DM 130 young patients with type 1 DM (mean age at diagnosis 10.08 +/- 2.62 yr). In 112 patients follow-up by fluorescein angiography was performed every 1.26 years with a mean of 5.41 fluorescein angiographies/patient.

METHODS

The stage of retinopathy was graded to detect minimal lesions. We also considered sex, pubertal stage, HLA, family history of DM, disease duration and HbA1c levels.

RESULTS

At first examination, 14 out of 127 (11%) readable angiographies showed minimal retinal changes. There was no statistically significant difference between the patients with or without lesions for all parameters considered. The 112 patients examined during follow-up were divided as follows: Group A: no retinopathy at first examination; Group A1: no retinopathy during follow-up; Group A2: retinal changes during follow-up; Group B: retinal changes at the first examination. Mean HbA1c value evaluated during the whole follow-up was lower in group A1 than in group A2. HbA1c levels at onset of the disease were significantly different in the three groups: in group A1 it was lower than in group A2 and in group B.

CONCLUSIONS

The presence of early lesions in the first year of disease in 11% of patients is probably due to the method of examination, which may detect even minimal retinal changes. This may be correlated to the acute metabolic failure present at the onset of disease. The prolonged follow-up seems to demonstrate that the early changes are not necessarily a negative prognostic factor in the evolution of diabetic retinopathy. We confirm that duration of DM and metabolic control are the main factors influencing the course of retinopathy in these young patients. Early fluorescein angiography is not particularly useful in the management of children with DM.

Homocysteinemia, serum folate and vitamin B12 in very young patients with diabetes mellitus type 1

BACKGROUND

Recently a link between hyperhomocysteinemia [HH(e)] and diabetic micro- and macrovascular complications has been reported. However, it is far from clear whether HH(e) is an epiphenomenon or a cause of angiopathic complications.

OBJECTIVE

To try to clarify this question we studied adolescents and young diabetic patients without or with only initial complications.

SUBJECTS

Plasma levels of basal homocysteinemia [H(e)], folate and vitamin B12 were measured in 76 young diabetic patients (age range 13.6-32.2 yr) and 70 normal volunteers matched for sex and age. In 68 diabetic patients and 53 controls we evaluated the levels of homocysteinemia 2 h after a methionine-loading test.

METHODS

Total (free + protein bound) plasma H(e) level was measured by HPLC.

RESULTS

Basal or post-load HH(e) occurred in 4.1% of diabetic patients and 12.4% of controls (frequencies not statistically different). In diabetic patients plasma homocysteine values were statistically lower than in controls, but this difference was present only in females. The females showed lower homocysteine values and higher folate levels than males only in the diabetic group. We did not find significant differences in H(e) levels between patients with early complications, late complications or without complications of any type.

CONCLUSIONS

Considering very young diabetic patients, the risk of hyperhomocysteinemia does not appear to be greater than in normal controls. Furthermore, our data seem to demonstrate that HH(e) is not a preexisting condition in diabetic patients, even in those predisposed to early complications.

Is statural growth predictable in utero? Follow-up from the second trimester of gestation to the 8th year of life

BACKGROUND

It is well known that birth weight is related to later childhood growth and adult height. It can therefore be hypothesized that this relationship exists also for fetal size before birth.

OBJECTIVE

To verify whether a child's final height can be predicted by sonographic biometry in utero.

SUBJECTS

We evaluated in 116 healthy children both ultrasound measurements in utero and postnatal measurements at a mean age of 6.0 +/- 1.4 years.

METHODS

The following fetal ultrasound measurements were obtained: crown-rump length in the first trimester; biparietal diameter, head circumference and femur length in the second and third trimester.

RESULTS

Midparental height of the children was correlated both with crown-rump length in the first trimester and with femur length (FL) in the second and third trimester. Predicted adult height was correlated both with FL in the second and third trimester, while present height of the child was correlated with FL only at the third trimester.

CONCLUSIONS

FL showed a close relationship with postnatal measurements. For the extreme values of FL, it seems possible to make quite an accurate prediction of the limits of future height. We can reasonably speculate, therefore, that the basis for the future growth of the child can be found in utero.

Birth weight affects final height in patients treated for growth hormone deficiency

OBJECTIVE

Birth weight influences both postnatal growth and the initial response to GH therapy in GH-deficient subjects, but its relationship to final height is uncertain. Therefore, we examined final height results in a group of subjects treated for GH deficiency who were born small, appropriate or large for gestational age (GA).

DESIGN

Retrospective study.

PATIENTS

108 GH-treated patients (age at diagnosis 11.1 +/- 2.0 years) affected by idiopathic and isolated GH deficiency (peak < 8 microg/l after pharmacological and/or nocturnal mean GH concentration </= 3.3 microg/l) were examined. Twenty-four had a birth weight < 3rd centile (2300 g +/- 268 - small for GA), 77 between the 3rd and 90th centile (3216 g +/- 317: appropriate for GA) and 7 above the 90th centile (4193 g +/- 143: large for GA).

MEASUREMENTS

All subjects reached final height (growth velocity < 0.5 cm/year in the last year of treatment) after hGH treatment (range 33-96 months) at a dose of 20 U/m2/week. The 3 groups of subjects started therapy at a similar height for chronological and bone age.

RESULTS

Final height in the small for GA group was - 1.71 +/- 0.93 standard deviation score (SDS), significantly lower than that of both appropriate (- 1.14 +/- 0.83 (P < 0.01)) and large (- 0.70 +/- 0.89 (P < 0.01)) for GA groups. Similarly, the small for GA group had a significantly lower height SDS increment from the start of therapy to adult height (0.54 +/- 0.84) than both the appropriate (0.99 +/- 0.78 (P < 0.05)) and the large (1.49 +/- 0.84 (P < 0.01)) for GA groups. The percentage of subjects with final height above target height was significantly different in the 3 groups: 21% for the small, 38% for the appropriate and 71% for the large for GA groups (P < 0.05). In the whole group of patients there was a positive correlation between birth weight and final height (r = 0.38; P < 0.0001).

CONCLUSIONS

The present study showed that our patients, affected by isolated and idiopathic GH deficiency but with different birth weights, despite starting treatment with a similar height and bone age delay, had different auxological outcomes. It seems, therefore, that final height is strongly influenced by birth weight which penalizes the smaller newborns and assists the larger ones.

Evidence for an interaction between adducin and Na(+)-K(+)-ATPase: relation to genetic hypertension

Adducin point mutations are associated with genetic hypertension in Milan hypertensive strain (MHS) rats and in humans. In transfected cells, adducin affects actin cytoskeleton organization and increases the Na(+)-K(+)-pump rate. The present study has investigated whether rat and human adducin polymorphisms differently modulate rat renal Na(+)-K(+)-ATPase in vitro. We report the following. 1) Both rat and human adducins stimulate Na(+)-K(+)-ATPase activity, with apparent affinity in tens of nanomolar concentrations. 2) MHS and Milan normotensive strain (MNS) adducins raise the apparent ATP affinity for Na(+)-K(+)-ATPase. 3) The mechanism of action of adducin appears to involve a selective acceleration of the rate of the conformational change E(2) (K) --> E(1) (Na) or E(2)(K). ATP --> E(1)Na. ATP. 4) Apparent affinities for mutant rat and human adducins are significantly higher than those for wild types. 5) Recombinant human alpha- and beta-adducins stimulate Na(+)-K(+)-ATPase activity, as do the COOH-terminal tails, and the mutant proteins display higher affinities than the wild types. 6) The cytoskeletal protein ankyrin, which is known to bind to Na(+)-K(+)-ATPase, also stimulates enzyme activity, whereas BSA is without effect; the effects of adducin and ankyrin when acting together are not additive. 7) Pig kidney medulla microsomes appear to contain endogenous adducin; in contrast with purified pig kidney Na(+)-K(+)-ATPase, which does not contain adducin, added adducin stimulates the Na(+)-K(+)-ATPase activity of microsomes only about one-half as much as that of purified Na(+)-K(+)-ATPase. Our findings strongly imply the existence of a direct and specific interaction between adducin and Na(+)-K(+)-ATPase in vitro and also suggest the possibility of such an interaction in intact renal membranes.

[Results of screening of congenital hypothyroidism and iodine excess in neonatal age]

We evaluated the distribution of TSH levels on dried blood spots (Delfia system-threshold value for recall 20 microU/ml) in 27,282 consecutive samples examined during 1993, in the Emilia-Romagna region. We also evaluated, by questionnaire, the frequency of iodine disinfection in the perinatal period in all centers that do blood spots. We also evaluated the distribution of TSH spot values according to the localization of the center in endemic or not endemic area of the region. Among the parameters we considered, only the sampling day (p < 0.02) and the maternity center (p < 0.0001) showed a significant influence on TSH spot values. With regard to the questionnaire, the centers which habitually used iodine disinfection in obstetrics (20/28) showed significantly higher percentages of TSH values over 10 microU/ml than the centers which did not use (3/28) or rarely used (4/28) this type of disinfection (p < 0.0001). The only center which used regular iodine disinfection of umbilical cord in all newborns, showed a percentage of TSH values over 10 microU/ml (25.8%) and a recall rate (2.5%) significantly higher than all other centers (p < 0.0001).

Helicobacter pylori and type 1 diabetes mellitus in children

BACKGROUND

Helicobacter pylori is a recognized gastroduodenal pathogen and H. pylori infection is one of the most common bacterial infections, usually acquired during childhood. However, diabetes mellitus is characterized by an increased susceptibility to infections.

METHODS

We compared the prevalence of H. pylori infection as well as cytotoxin-associated gene A-CagA-and vacuolating cytotoxin gene A-VacA-positivity in 103 children and adolescents with type 1 diabetes mellitus and in 236 nondiabetic children. We used a novel Recombinant ImmunoBlot Assay-Strip (RIBA SIA) with individual band for whole H. pylori lysate and recombinant CagA and VacA.

RESULTS

H. pylori-positive subjects, both diabetics and controls, were significantly older than negative subjects. In the whole group of diabetic patients the prevalence of each of the three reactivities was higher than in control subjects, reaching significance only for lysate. Only diabetic patients over 12 years of age, with a longer disease duration, had a higher prevalence of positive cases, although not significantly so.

CONCLUSIONS

In the first few years of disease, diabetic children do not differ from the nondiabetic population. Subsequently they show an H. pylori seroprevalence tendentially higher than that of controls of the same age. Therefore, H. pylori infection acquired in childhood and lasting several years, could be one of the causes of chronic atrophic gastritis, which is more frequent in longstanding diabetes mellitus.

Helicobacter pylori infection and cytotoxic antigen associated gene "A" status in short children

BACKGROUND

Helicobacter pylori is now an accepted gastroduodenal pathogen and is being investigated for possible implications in nongastroenterological conditions such as growth impairment. Subjects infected by cytotoxic Cag-A positive strains seem more likely to develop serious gastroduodenal diseases but the possible role of Cag-A positive strains in non gastroenterological diseases has not been fully investigated.

OBJECTIVE

1) To evaluate the prevalence of Helicobacter pylori infection and Cag-A positivity in short children compared to auxologically normal children. All the subjects were without gastro-intestinal symptoms and were not obese or significantly underweight. 2) To verify the reliability of the ELISA assay for H. pylori.

SUBJECTS

H. pylori infection was assessed in 338 children, 182 auxologically normal and 156 short children, with and without deficiency in growth hormone, by the determination of specific IgG antibody. In 79 subjects (all seropositive and a random sample of seronegative children), 13C-urea breath test and cytotoxic Cag-A positive strains were examined.

RESULTS

The overall seroprevalence of H. pylori infection by IgG antibody was 18/156 (11.5%) and 13/182 (7.1%) in short and auxologically normal children respectively. The 13C-urea breath test was positive in 29 children: 17 (10.9%) short and 12 (6.6%) auxologically normal. Western blotting documented infection by cytotoxic Cag-A positive strains in 12/17 (70.6%) and 8/12 (66.6%) of short and auxologically normal children respectively. None of the differences between the two groups were significant.

CONCLUSIONS

1) We found a similar prevalence of H. pylori infection and Cag-A positivity in two large pediatric populations of short or auxologically normal children. Therefore: 1) Our data did not confirm a role of H. pylori infection in short stature in children. 2) We found a high reliability of ELISA assay for the detection of IgG antibodies compared to breath test.

Outcome of premature thelarche: relation to puberty and final height

BACKGROUND

There is a debate about the possible progression of idiopathic premature thelarche towards precocious or early puberty.

OBJECTIVE

To evaluate height and age at onset of puberty in a group of girls with a history of idiopathic premature thelarche.

STUDY DESIGN

The height and age at onset of puberty of 42 girls now over 10 years of age who were diagnosed with isolated premature thelarche before the age of 3 years were evaluated.

RESULTS

Menarche was reached before or at 11 years of age in 13.5% of this group of girls. This percentage of early menarche was higher than would be expected from historical controls in the general population, but was consistent with maternal age of menarche. The mean (SD) height of the girls (n = 15) who achieved adult height was 162.9 (6.3) cm, which was slightly higher than the mean (SD) relative mid-parental height (160.7 (6.7) cm).

CONCLUSIONS

Isolated premature thelarche with onset before 3 years of age progresses towards precocious puberty, although this was consistent with the maternal age of menarche. Furthermore, adult height was normal when compared with population norms in all patients.

Helicobacter pylori and diminished growth in children: is it simply a marker of deprivation?

Helicobacter pylori is an accepted gastroduodenal pathogen and has recently been investigated for possible implications in non gastroenterological diseases such as growth impairment coronary heart disease and diabetes. Infection by cytotoxic, i.e., CagA or VacA positive strains seems more likely to lead to more serious gastroduodenal diseases compared to infection by non cytotoxic strains, but the possible role of CagA or VacA positive strains in non gastroenterological diseases has not been investigated. Aim of the present study was to evaluate the prevalence of Helicobacter pylori infection as well as CagA and VacA positivity in three paediatric populations auxologically normal, hyposomic and diabetic children. Sera from a total of 522 children (auxologically normal: 246, hyposomic: 164, diabetic: 112) were analyzed by a novel Recombinant ImmunoBlot Assay-Strip Immunoblot Assay--RIBA SIA--which contain individual band for whole Helicobacter pylori lysate and recombinant CagA and VacA. The overall seroprevalence of reactivities against Helicobacter pylori lysate, CagA and VacA were: 7.3%, 9.3%, 6.9% vs 11.6%, 7.9%, 8.5% vs 14.3%, 13.4%, 8% (p = NS) in auxologically normal, hyposomic and diabetic children, respectively. Summarizing, we found a similar prevalence of reactivity against both whole Helicobacter pylori lysate as well as recombinant CagA and VacA between auxologically normal, hyposomic and diabetic children. Our data do not support a possible role of Helicobacter pylori in diminished growth in children.

Unusual magnetic resonance imaging findings of the sellar region in subjects with hypopituitarism: report of 4 cases

Out of 323 consecutive growth hormone deficient patients who underwent magnetic resonance imaging (MRI), we describe the clinical and neuroradiological characteristics of four patients in whom MRI revealed unusual pictures of the sellar area. They were selected as unique in their morphological picture and representative of rare conditions. At presentation all subjects had short stature, growth hormone (GH) deficiency and complex phenotypical abnormalities. Patient 1. Female affected by vaginal atresia and sinus urogenitalis, polydactyly and syndactyly with Y-shaped metacarpals. MRI at age 11.2 years revealed normal pituitary, but hypothalamic mass occupying the suprasellar and interpeduncular cistern. The diagnosis of Hall-Pallister syndrome was made. Patients 2 and 3. Two sisters with a history of epilepsy both showing mild intellectual deficiency, midface hypoplasia and ectodermal dysplasia. MRI at age 8 and 12 years respectively displayed in both cases a round hypointensity protruding from the dorsum sellae into a normal pituitary. The diagnosis was sellar spine. Patient 4. Male with a history of postnatal hypoglycemia showing microphallus and clinical features of severe hypopituitarism. Hormonal evaluation at age 8 months confirmed multiple pituitary hormone deficiencies and MRI at age 6 years showed absent anterior lobe, rudimentary stalk and posterior lobe ectopia. The diagnosis was pituitary aplasia. The patients described show that MRI in pituitary dwarfs can reveal unusual intrasellar findings and allow the correct diagnosis of rare syndromes. Our patients also demonstrate the wide variability in the association of hypopituitarism with midline congenital abnormalities and the possible combination with complex syndromes.

Modifications of metabolic control in type 1 diabetic children and adolescents: experience over the last 20 years

The aim of this retrospective study was to verify whether the daily number of insulin injections could have affected metabolic control in 181 unselected diabetic patients (age 0.66-14.75 yr at onset of diabetes) followed in our clinic from the 1970s to the 1990s. They were evaluated regularly since onset of disease for a mean follow-up period of 6.8 years. The factor with the greatest effect on HbA1c levels was the year of disease onset, which was negatively correlated with HbA1c independently of the daily number of injections and disease duration. Disease duration showed an effect on metabolic control only in the first 5 years of disease. Daily insulin injections affected metabolic control above all as regards 1 vs 2 or more injections. Regarding the change in insulin regimen from 2 to 3-4 injections, there was an improvement in metabolic control in patients with HbA1c > 9% and a worsening in those with HbA1c < 7%/ After the first 5 years of the disease HbA1c levels were higher in adolescent patients than in both younger and older patients. In conclusion, increasing the daily number of injections does not seem in itself capable of eliciting marked improvement in metabolic control, as in our young diabetic patients in the last decade. Multiple insulin injection therapy seems to be mostly indicated for patients with poor control and for adolescents.

Developmental pattern of fetal growth hormone, insulin-like growth factor I, growth hormone binding protein and insulin-like growth factor binding protein-3

AIMS

To evaluate the developmental pattern of fetal growth hormone (GH), insulin-like growth factor I (IGF-I), GH binding protein (GHBP) and IGF binding protein-3 (IGF-3); to determine the implications for fetal growth.

METHODS

Serum GH, IGF-I, GHBP and IGFBP-3 were measured in 53 fetuses, 41 aged 20-26 weeks (group A) and 12 aged 31-38 weeks (group B). Fetal blood samples were obtained by direct puncture of the umbilical vein in utero. Fetal blood samples were taken to rule out beta thalassaemia, chromosome alterations, mother to fetus transmissible infections, and for maternal rhesus factor. GHBP was determined by gel filtration chromatography of serum incubated overnight with 125I-GH. GH, IGF-I and IGFBP-3 were determined by radioimmunoassay.

RESULTS

Fetal serum GH concentrations in group A (median 29 micrograms/l, range 11-92) were significantly higher (P < 0.01) than those of group B (median 16.7 micrograms/l, range 4.5-29). IGF-I in group A (median 20 micrograms/l, range 4.1-53.3) was significantly lower (P < 0.01) than in group B (median 75.2 micrograms/l, range 27.8-122.3). Similarly, IGFBP-3 concentrations in group A (median 950 micrograms/l, range 580-1260) were significantly lower than those of group B (median 1920 micrograms/l, range 1070-1770). There was no significant difference between GHBP values in group A (median 8.6%, range 6.6-12.6) and group B (median 8.3%, range 6-14.3). Gestational age correlated positively with IGF-I concentrations (P < 0.0001) and IGFBP-3 (P < 0.0001) and negatively with GH (P < 0.0001). GHBP values did not correlate with gestational age. Multiple regression analysis showed a negative correlation between GH:IGF-I ratio and fetal growth indices

CONCLUSIONS

The simultaneous evaluation of fetal GH, IGF-I, IGFBP-3 and GHBP suggests that the GH-IGF-I axis might already be functional in utero. The progressive improvement in the efficiency of this axis in the last part of gestation does not seem to be due to an increase in GH receptors.

Final height of patients treated for isolated GH deficiency: examination of 83 patients

The aim of the present study was to evaluate retrospectively the influence of various auxological and laboratory parameters on final height in a group of GH-deficient children after replacement therapy and to compare their final height with that of a group of short children with normal GH secretion and hence not treated. The final height was evaluated of 83 patients (51 males and 32 females) affected by idiopathic isolated GH deficiency and treated with recombinant human GH (hGH) for 2-7 years. Inclusion criteria at the start of treatment were short stature (mean height for chronological age in standard deviation score (SDS) -2.21) due to idiopathic isolated GH deficiency (GH peak < 8 micrograms/l after two pharmacological tests and/or mean GH concentration < 3.3 micrograms/l during the night) and treatment with recombinant hGH for at least 2 years at a dose of 15-20 U/m2 per week by s.c. injection for 6 or 7 days/ week. Mean chronological age at diagnosis was 12.2 +/- 1.7 years; 35 were prepubertal and 48 pubertal. The final height of 51 untreated short stature (mean height for chronological age in SDS -2.13 at diagnosis) subjects (42 males and 9 females: 29 prepubertal and 22 pubertal at diagnosis with mean chronological age 11.6 +/- 2.4 years) with normal GH secretion was also evaluated. In the treated subjects final height SDS was higher than that of the untreated group (-1.3 vs -1.7 SDS; P = 0.01). Both treated and untreated subjects showed a final height lower than target height, but 39% of the treated subjects vs only 20% of the untreated group (P = 0.035) had a final height greater than target height. In the treated subjects this percentage was higher in the patients improving their height for bone age in the first years of therapy. While treated females showed a positive correlation only between target and final height (P = 0.0001), in treated males final height correlated with the Bayley-Pinneau prediction at diagnosis, height for chronological age and bone age at diagnosis and target height. Patients who started therapy before puberty also showed these correlations with data calculated at the onset of puberty, together with a correlation with chronological age at the onset of puberty. When considering the influence of GH response at tests on final height, the percentage of subjects exceeding target height increased progressively according to the severity of the GH deficiency. There was no difference in height gain between the patients starting therapy before or during puberty. The height gain, however modest, obtained by our treated patients, the number of patients with final height greater than target height and the favourable comparison with the untreated short-stature subjects represent a promising result, which could be improved by personalizing treatment.

Abnormal insulin response to glucose following treatment for Wilms' tumor in childhood

To determine whether beta-cell function could be impaired by the treatment for Wilms' tumour (WT) in childhood. We investigated the insulin secretion of 44 survivors of WT (22 males) with a median off-treatment follow up of 8.3 years (range 1-19.8). All patients had an intravenous glucose tolerance test (IVGTT) (0.5 gm/kg, max 25 g) to determine the first-phase insulin response (FPIR) (sum of the 1- and 3-min insulin concentrations). Median age at the time of the study was 12.7 years (range 4.2-22.7). Eight subjects (7 males) had a FPIR value below the 3rd percentile, and 7 (3 males) above the 97th centile. Among the 22 patients who received radiotherapy. 7 (6 males) showed a FPIR < 3rd percentile versus only 1 (a male) of the 22 patients who received no radiation (31.8% vs 4.5%; P < 0.05). Analysis of variance showed that the time elapsed since therapy had a significant role on the development of low FPIR only in males. The 7 patients with an insulin release > 97th percentile did not show any significant difference compared to subjects with lower insulin values for weight, age at diagnosis, sex, time elapsed since treatment, radiotherapy and chemotherapy protocol.

CONCLUSION

An impaired insulin response is evident in some patients treated for WT in childhood, mainly in male patients who received abdominal radiotherapy and were examined a longer time after therapy. We hypothesize that this decreased insulin release is related to damage due to radiotherapy and therefore a careful follow up is recommended in adulthood in these patients.

Renal Na,K-ATPase in genetic hypertension

Milan hypertensive rats (MHS) develop hypertension because of a primary renal alteration. Both apical and basolateral sodium transport are faster in membrane vesicles derived from renal tubules of MHS than in those of Milan normotensive control rats (MNS). These findings suggest that the increased renal sodium retention and concomitant development of hypertension in MHS may be linked to an altered transepithelial sodium transport. Since this transport is mainly under the control of the Na-K pump, we investigated whether an alteration of the enzymatic activity and/or protein expression of the renal Na,K-ATPase is detectable in prehypertensive MHS. We measured the Na,K-ATPase activity, Rb+ occlusion, turnover number, alpha 1- and beta 1-subunit protein abundance, and alpha 1 and beta 1 mRNA levels in microsomes from renal outer medulla of young (prehypertensive) and adult (hypertensive) MHS and in age-matched MNS. In both young and adult MHS, the Na,K-ATPase activity was significantly higher because of an enhanced number of active pump sites, as determined by Rb+ occlusion maximal binding. The higher number of pump sites was associated with a significant pretranslational increase of alpha 1 and beta 1 mRNA levels that preceded the development of hypertension in MHS. Since a molecular alteration of the cytoskeletal protein adducin is genetically associated with hypertension in MHS and is able to affect the actin-cytoskeleton and Na-K pump activity in transfected renal cells, we propose that the in vivo upregulation of Na-K pump in MHS is primary and linked to a genetic alteration of adducin.

Hypertension-associated point mutations in the adducin alpha and beta subunits affect actin cytoskeleton and ion transport

The adducin heterodimer is a protein affecting the assembly of the actin-based cytoskeleton. Point mutations in rat adducin alpha (F316Y) and beta (Q529R) subunits are involved in a form of rat primary hypertension (MHS) associated with faster kidney tubular ion transport. A role for adducin in human primary hypertension has also been suggested. By studying the interaction of actin with purified normal and mutated adducin in a cell-free system and the actin assembly in rat kidney epithelial cells (NRK-52E) transfected with mutated rat adducin cDNA, we show that the adducin isoforms differentially modulate: (a) actin assembly both in a cell-free system and within transfected cells; (b) topography of alpha V integrin together with focal contact proteins; and (c) Na-K pump activity at V(max) (faster with the mutated isoforms, 1281 +/- 90 vs 841 +/- 30 nmol K/h.mg pt., P < 0.0001). This co-modulation suggests a role for adducin in the constitutive capacity of the epithelia both to transport ions and to expose adhesion molecules. These findings may also lead to the understanding of the relation between adducin polymorphism and blood pressure and to the development of new approaches to the study of hypertension-associated organ damage.

Association between plasma membrane (Ca+Mg) ATPase and calpain/calpastatin system in rat erythrocytes

We studied the activity of plasma membrane (Ca+Mg)ATPase from erythrocytes of Milan hypertensive rat strain (MHS) and Milan low calpastatin rat strain (MLCS), that show an activity level of the specific calpain inhibitor, calpastatin, about five fold reduced in comparison with the Milan normotensive rat strain (MNS), while the protease activity level is similar. This imbalance of calpain:calpastatin ratio leads to a decrease of the erythrocyte plasma membrane (Ca+Mg)ATPase activity and to the appearance of 124 kDa fragments, which are the typical products of proteolytic calpain action on the 136 kDa (Ca+Mg)ATPase native form.

A new rat model for studying the calpain-calpastatin system

A recombinant rat strain--Milan low-calpastatin strain (MLCS)--was derived from Milan hypertensive (MHS/Gib) and Milan normotensive (MNS/Gib) strains. The MLCS rats have normal blood pressure and low calpastatin activity, and this strain is proposed as a model for studies of the calpain-calpastatin system, which is involved in important cellular mechanisms. Calpastatin polymorphism was observed in 10 different strains of laboratory rats and a single locus hypothesis is suggested as the mode of inheritance.

An 8-year follow-up of anti-insulin antibodies in diabetic children: relation to insulin autoantibodies, HLA type, beta-cell function, clinical course and type of insulin therapy

In 105 children and adolescents with IDDM, insulin antibodies were detected as a percentage of radiolabelled insulin both at onset of disease and during the first 8 years of treatment. At diagnosis, 29 patients (27%) were insulin autoantibody positive (IAA+). An inverse relationship was found between IAA levels and age at diagnosis. No significant correlation was seen between IAA positivity and HLA antigens, while there was a negative correlation between IAA and C-peptide levels in the second year of the disease. The percentage of insulin antibody (IA) positive patients increased after insulin administration, with a maximum peak between the first and second year of the disease. The IA response to insulin therapy was similar in IAA+ and IAA- patients, while it was greater in younger children. No relationship was found between IA levels and haemoglobin A1c values, daily insulin requirement, HLA and early complications. No difference in either percentage of positivity or IA levels was seen in patients treated continually for the first 5 years of the disease with monocomponent porcine insulin or human insulin. A negative correlation was found between IA and C-peptide levels in the first and second years of the disease. In conclusion, we have shown that, even after many years of disease, neither IAA nor IA, induced in equal measures by current human insulin preparations, have significant effects on the clinical course of the disease.

Value and limits of pharmacological and physiological tests to diagnose growth hormone (GH) deficiency and predict therapy response: first and second retesting during replacement therapy of patients defined as GH deficient

There is currently a debate about the use of pharmacological and physiological tests to define GH deficiency and predict response to GH therapy. In addition, a good response to therapy has also been described in subjects without GH deficiency. For further information, we reevaluated GH secretion during replacement therapy in a group of children defined as GH deficient and examined response to therapy in the subjects subdivided according to secretion. One hundred eighty four children (113 boys and 71 girls) initially diagnosed with GH deficiency by means of pharmacological (peak < 8 micrograms/L after arginine and L-dopa tests) and physiological tests (mean nocturnal concentration < or = 3.3 micrograms/L during sleep test) underwent the same tests 2.8 +/- 1.1 yr after start of GH therapy. Sixty eight patients were retested 1.5 +/- 0.4 yr after first retesting. At diagnosis 122 subjects had pathological pharmacological and physiological tests (group A), 30 subjects normal sleep test with pathological pharmacological tests (group B), and 32 subjects pathological sleep test with normal pharmacological tests (group C). At diagnosis 140 subjects were prepubertal and 44 pubertal. To evaluate response to therapy in relation to GH secretion at diagnosis and at both retestings, a number of auxological parameters were calculated during treatment. At first retesting, 107 subjects (58.1%) changed initial group of diagnosis, 34 of whom (18.5%) presented normal secretion in both pharmacological and physiological tests (group D). At second retesting, 31 of the 68 subjects reexamined (45.6%) changed first test results, and 33 (48.5%) reverted to the initial group of diagnosis; none of the 6 subjects of group D maintained normal secretion. Although the percentage of normalized subjects was higher in pubertal subjects (36.4%; P = 0.0003) than prepubertal subjects (8.9%), puberty did not prevent a reduction of secretion in some subjects. Response treatment during the first year of therapy was similar in the various groups. GH secretion seems to change in both prepubertal and pubertal children diagnosed with GH deficiency when pharmacological and physiological tests are repeated over time. Moreover, such tests may not represent a reliable tool for predicting response to treatment. GH secretion normalization at retesting may not necessarily represent the end of a transient secretory defect.

Propionyl-L-carnitine prevents myocardial mechanical alterations due to pressure overload in rats

This study investigated if propionyl-L-carnitine (PLC) treatment can directly affect cardiac mechanics, secondary to increase in myocardial carnitine content, in rats with aortic constriction and sham-operated controls. After weaning, rats were fed one of the following diets for 8 wk: 1) a low-carnitine diet (containing 2 nmol/g carnitine); 2) the same diet supplemented with PLC (710 mumol/kg body wt); 3) L-carnitine (LC; 118 mumol/kg body wt, given in tap water; or 4) a standard diet (containing 56 nmol/g carnitine). A 4-wk constriction of the abdominal aorta caused left ventricular hypertrophy associated with significantly prolonged timing parameters and reduced rate of tension decay in papillary muscles. In group 2, however, PLC treatment prevented hypertrophy-induced changes in these parameters and the reduction in unloaded shortening velocity in skinned trabeculae. Finally, PLC treatment maintained the relative proportion of myosin heavy chain isoforms in left ventricular wall of animals subjected to aortic constriction. Both PLC and LC completely prevented carnitine depletion due to hypertrophy and to dietary restriction. Because LC did not modify papillary muscle contractile function, these results demonstrate that PLC affects hypertrophy-induced changes in muscle mechanics and ventricular wall composition independently of tissue carnitine levels.

Two point mutations within the adducin genes are involved in blood pressure variation

The Milan hypertensive strain of rats (MHS) develops a genetic form of renal hypertension that, when compared to its normotensive control (MNS), shows renal dysfunction similar to that of a subset of human patients with primary hypertension. MHS and MNS were shown to be homozygous by multilocus minisatellite analysis and monolocus microsatellite markers. We show here that one point mutation in each of two genes coding for the membrane skeleton protein adducin is associated with blood pressure in the Milan strain of rats. Adducin is a heterodimer formed by alpha and beta subunits that promotes the assembly of actin with spectrin. MHS and MNS differ, respectively, by the amino acids Y and F at position 316 of the alpha subunit. In the beta-adducin locus, MHS is always homozygous for R at position 529 while in MNS either R or Q occurs in that position. The R/Q heterozygotes showed lower blood pressure than any of the homozygotes. In vitro phosphorylation studies suggest that both of these amino acid substitutions occur within protein kinase recognition sites. Analysis of an F2 generation demonstrated that Y alleles segregated with a significant increment in blood pressure. This effect is modulated by the presence of the R allele of the beta subunit. Taken together, these findings strongly support a role for adducin polymorphisms in causing variation of blood pressure in the Milan strain of rats.

Relationships among alterations in renal membrane sodium transport, renin and aminopeptidase M activities in genetic hypertension

Rats of the Milan Hypertensive Strain (MHS) may be considered a useful model for understanding the genetic molecular mechanism underlying a primary form of hypertension in at least a subgroup of patients. Many differences between MHS and its normotensive control strain (MNS) were found at the organ, cellular and biochemical level. In the present investigation renal cell membrane proteins (BBMV) were analysed by two-dimensional electrophoresis and a difference between MHS and MNS was shown in a polypeptide of 32 kDa, subsequently identified as the C-terminal fragment of aminopeptidase M (APM). The activity of the enzyme was higher in MHS. Genetic relationships between this enzyme and the other biochemical cellular abnormalities of MHS, namely sodium transport in BBMV and renin activity in kidney cortex were investigated in MHS, MNS and in two inbred recombinant strains. This analysis showed that faster sodium transport, low kidney levels of renin and hypertension, but not differences in two-dimensional electrophoretic pattern and in aminopeptidase M activity, cosegregated in recombinant strains. These results are consistent with the hypothesis that the faster sodium transport can be considered a primary cellular abnormality responsible for hypertension in MHS and that the aminopeptidase difference is not involved in the cellular abnormalities.

Characteristics of a ouabain-like factor from Milan hypertensive rats

Ouabain-like factor (OLF) has been extracted from hypothalamus and adrenal glands of the ox and rats of the Milan hypertensive strain (MHS) and their normotensive controls (MNS). OLF was identified by its ability (a) to inhibit ouabain-sensitive 86Rb uptake into human erythrocytes, (b) to displace [3H]ouabain binding, and (c) to inhibit purified dog kidney Na-K-ATPase. Rat and bovine OLF have similar characteristics. Those that are close to ouabain are (a) ligand conditions for maximal inhibitory activity, (b) high-performance liquid chromatography retention time, (c) reversibility of inhibitory activity on Na-K-ATPase, (d) reduced Na-K-pump inhibitory activity by K+, (e) high affinity for Na-K-ATPase, and (f) no activity on Ca(2+)-ATPase. OLF does not resemble ouabain because the capacity of OLF to inhibit ouabain low-affinity Na-K-ATPase isoform is greater than that of ouabain. The yield of OLF is greater from MHS than MNS hypothalamic and adrenal extracts. These findings represent the first direct evidence that a higher amount of OLF is present in tissues from genetically hypertensive rats than from their inbred normotensive controls, maintained under the same dietary and environmental conditions. This further supports previous observations on the role of OLF in the pathogenesis of MHS hypertension.

Na+/K+/Cl- cotransport in resealed ghosts from erythrocytes of the Milan hypertensive rats

The erythrocytes (RBC) of the Milan hypertensive rats (MHS) have a smaller volume and faster Na+/K+/Cl- cotransport than RBC from normotensive controls (MNS). The difference in Na+/K+/Cl- cotransport is no longer present in inside-out Vesicles (IOV) of RBC membrane. To differentiate between cytoplasmic or membrane skeleton abnormalities as possible causes of these differences. Resealed ghosts (RG) were used to measure ion transport systems. The following results have been obtained: (1) RG from MHS have a smaller volume than MNS (mean +/- S.E. 20.7 +/- 0.45 vs. 22.09 +/- 0.42 fl, P < 0.05). (2) RG showed a bumetanide-sensitive Na efflux that retains the characteristics of the Na+/K+/Cl- cotransport of the original RBC: it is K(+)- and Cl(-)-sensitive and dependent on the intracellular Na+ concentration. (3) The Na+/K+/Cl- cotransport was faster in RG from MHS than in those from MNS (mean +/- S.E. 0.095 +/- 0.01 vs. 0.066 +/- 0.01 rate constant h-1, P < 0.01). These results, together with those of IOV, support the hypothesis that an abnormality in the membrane skeletal proteins may play a role in the different Na+/K+/Cl- cotransport modulation between MHS and MNS erythrocytes.

Ouabainlike factor in Milan hypertensive rats

Ouabainlike factor (OLF) has been extracted from the hypothalamus and adrenals of the ox and rats of the Milan hypertensive strain (MHS) and their normotensive controls (MNS). OLF was identified by its ability to 1) inhibit ouabain-sensitive 86Rb uptake into human erythrocytes, 2) displace [3H]ouabain binding, and 3) inhibit purified dog kidney Na-K-adenosinetriphosphatase (ATPase). Rat and bovine OLF have similar characteristics. Those that are close to ouabain are 1) ligand conditions for maximal inhibitory activity, 2) high-performance liquid chromatography retention time, 3) reversibility of inhibitory activity on Na-K-ATPase, 4) reduced Na-K pump inhibitory activity by K, 5) high affinity for Na-K-ATPase, and 6) no activity on calcium ATPase. OLF does not resemble ouabain in the following characteristics: 1) the capacity of OLF to inhibit ouabain low-affinity Na-K-ATPase isoform is greater than that of ouabain and 2) the capacity of OLF to inhibit renal Na-K-ATPase isoforms is greater when the enzyme is obtained from adult rather than young rats. The yield of OLF is greater from MHS than MNS. These findings represent the first direct evidence that a higher amount of OLF is present in tissues from genetically hypertensive rats than from their inbred normotensive controls, maintained under the same dietary and environmental conditions. This further supports previous observations on the role of OLF in the pathogenesis of MHS hypertension.

[Neuropsychological follow-up of children with phenylketonuria treated early]

We evaluated, yearly, the neuro-psychological development in 16 out of the 27 children with phenylketonuria detected via neonatal screening in the years 1980-90. 14 children had the classical form, while 2 had "variant" type of phenylketonuria. Development quotients always were slightly lower in patients than in controls, but the greatest difference was seen at 1 year of age (92.5 +/- 6.7 vs 101.6 +/- 2.2). At age 6 years, 4 children out of 11 had a IQ equal or below 90.2 of them had neonatal asphyxia, while the others showed, after age 2-4, constantly elevated phenylalanine levels. Four children had a bad metabolic control, as from the age of 2-4 year, and only 1 of them showed a normal IQ at 6 years of age. Regression analyses were used to determine the best predictors of IQ. Parents' social level stood out as the best predictor of IQ at 6 years of age. If this parameter was excluded, phenylalanine level, especially at age 4, best predicted IQ. The following variables had no influence: age at start of diet (they were all begun on diet within the first month of life), pre-diet phenylalanine levels and phenylalanine levels at 1 year of age (all children were, at this age, on good control), DQ (Development Quotient) at age 1. A high percentage (10 out 14) of hyperactive and psychologically instable children was also found, but with no correlations with IQ levels.

Sodium transport kinetics in erythrocytes and inside-out vesicles from Milan rats

This paper describes the kinetics of the Na(+)-K+ pump and the Na(+)-K(+)-Cl- cotransport in sodium-loaded erythrocytes and of the Na(+)-K(+)-Cl- cotransport in erythrocyte inside-out vesicles (IOV) from Milan hypertensive (MHS) and normotensive (MNS) rats in order to evaluate the possible role of intracellular factor(s). In intact erythrocytes, no difference was detectable in the Na(+)-K+ pump kinetics between the two strains while the apparent affinity (Km) of Na(+)-K(+)-Cl- cotransport for internal sodium was significantly greater and the maximal rate of sodium transport lower in MHS when compared with MNS rats. IOV, which are depleted of cytoskeleton, showed a bumetanide-sensitive potassium- and chloride-dependent sodium uptake. However, the erythrocyte differences in Na(+)-K(+)-Cl- cotransport activity and the Km between strains disappeared in IOV, suggesting tha the altered sodium transport of MHS erythrocyte might be due to some intracellular factor or a membrane skeleton protein abnormality.

Molecular cloning of an adducin-like protein: evidence of a polymorphism in the normotensive and hypertensive rats of the Milan strain

Differences genetically associated with the development of hypertension in a strain of genetically hypertensive rat (MHS) were described in ion transport across erythrocyte membranes compared to normotensive control (MNS). Antibodies against the MNS ghost proteins were raised in the MHS, producing an immunoreaction against a 105 KDa protein later identified as adducin. A clone coding for a portion of mouse adducin was isolated with these antibodies. Using this clone, overlapping cDNA clones coding for a 63 KDa adducin-like protein were isolated. A family of related mRNAs of about 3500, 3800, 4200 nt, was found to be present in spleen, kidney and heart tissues. Similar mRNAs and an additional tissue specific 8000 nt mRNA are present in brain. All mRNAs seem to be generated by alternative splicing from the transcript of a single gene. An interesting polymorphism, a Gln to Arg substitution, was detected in the carboxiterminal area of rat adducin 63.

What will be the adult height of coeliac patients?

We studied three groups of patients with coeliac disease: group 1 = 95 adult patients with gastro-intestinal symptoms diagnosed after reaching adult height, 41 of whom had had symptoms during childhood; group 2 = 23 adult patients with classic coeliac disease treated before or during puberty; group 3 = 11 coeliac children with short stature and no gastro-intestinal symptoms diagnosed and treated before or during puberty. We evaluated the adult height in groups 1 and 2 and the growth during the first years of diet in group 3. Our study leads us to the following conclusions. Dieting leads to a modest increase (on average not more than 3 cm) of the final height of coeliac patients. Subjects with gastro-intestinal symptoms who have been treated before adulthood reach a mean height similar to the normal population and have a slightly better adult height than non-treated subjects. This difference seems to exist only in men and this might be related to puberty evolving more rapidly in women receiving treatment. Subjects without symptoms during childhood reach a normal final height even without treatment. In our patients, early treatment seemed to have no great effect on adult height.

Calpastatin level in spontaneously hypertensive rats

We studied calpastatin activity in erythrocytes of Milan hypertensive and prehypertensive rats, in their normotensive controls, in F1 and F2 hybrids, and in two inbred strains derived from F2, one hypertensive and the other normotensive. Our results show that the decrease in calpastatin activity observed in Milan hypertensive rats was not caused by hypertension, it was transmitted in a recessive way in heterozygous, and it was not correlated to hypertension.

Growth hormone, insulin-like growth factor I, insulin and C-peptide during human fetal life: in-utero study

Serum growth hormone (GH), insulin-like growth factor (IGF-I), insulin and C-peptide were measured by RIA in fetal blood collected in utero by umbilical cord puncture performed for a variety of indications. Eighty-four fetuses were aged 19-25 weeks and 14 were 26-37 weeks. IGF-I values were lower than the sensitivity of the method. The range for GH was 3-197 micrograms/l (GH-micrograms/l x 2 = mU/l), for insulin 14.3-117 pmol/l, for C-peptide 66.2-827.5 pmol/l. GH significantly increased from week 19 to 25; insulin and C-peptide levels increased from week 19 to 37. GH levels at 19-25 weeks were significantly higher in fetuses with femoral length less than the 5th compared with those with femoral length greater than the 95th centile for that age. GH and insulin levels did not correlate with weight at birth or with maternal hormone levels. These data provide evidence for a presence in living fetuses, from the 19th week, of high levels of GH and of insulin levels not very different from those in adults but these hormones do not seem to be directly responsible for fetal growth.

Variability of growth hormone response to pharmacological and sleep tests performed twice in short children

Forty-nine children with short stature (age range, 4.1-15.9 yr) were examined. Twenty-four (group 1) were submitted twice to an arginine and a sleep test (12-h overnight GH profile). Twenty-five patients (group 2) were submitted twice to an arginine and L-dopa test. Coefficients of variation were calculated between both the results of pharmacological (peak and area under the curve) and sleep tests [mean GH concentration (MGHC), peak, area under the curve, number of peaks above 5 micrograms/L, and peak area]. In group 1 the coefficient of variation of sleep test parameters was significantly lower than that of pharmacological tests (P less than 0.01 to less than 0.001). In the sleep test the area under the curve and MGHC were the most constant parameters. Group 2 showed no difference between the coefficients of variation of the two pharmacological tests. Considering groups 1 and 2 together, the coefficients of variation of the sleep test, in particular the MGHC and area under the curve, were lower than those of the two pharmacological tests. Eight of 24 subjects in group 1 showed a low GH level in 1 series of tests, and a normal level in the other series. Five of 18 subjects in group 2 showed an abnormally low GH response to the arginine and L-dopa tests and a normal response to the 2 repeated tests. Therefore, to prevent an erroneous interpretation of the GH test results, it is very important to perform a sleep test and repeat it whenever GH secretion seems to be deficient or at the lower limits of normalcy.

Microalbuminuria in diabetic children and adolescents. Relationship with puberty and growth hormone

Urinary albumin excretion (UAE) was determined by radioimmunoassay in two 24 h urine collections from 125 diabetic children and adolescents and from 71 normal children matched for age and sex. Thirteen patients (10.4%) aged greater than 12 years had microalbuminuria, i.e. log transformed UAE levels above the upper normal range (24.5 mg/24 h). UAE values were positively correlated with age, GH secretion, but not with duration of disease, glycosylated hemoglobin, renal size or N-acetyl-beta-glucosaminidase excretion. Diabetic normoalbuminuric children aged 10 years and older had significantly higher UAE than controls and than younger diabetic patients matched for duration of disease. HLA DR3/DR4 heterozygosity frequency was significantly higher (p less than 0.01) in the microalbuminuric group than in the normoalbuminuric. All microalbuminuric subjects (n = 8) with short duration of disease (3.92 +/- 3.43 yr) developed diabetes at puberty. In conclusion, our cross-sectional study suggests: if a number of factors are combined, i.e. HLA DR3/DR4 heterozygosity, onset of disease at puberty and higher GH values, the probability of developing abnormal levels of UAE will increase.

Na+/K+/Cl(-)-cotransporter mediated Rb+ fluxes in membrane vesicles from kidneys of normotensive and hypertensive rats

This paper describes experiments to examine Rb+ fluxes via the Na+/K+/Cl- cotransporter in membrane vesicles from renal outer medulla of three strains of rat: (A) Wistar (B) Milan hypertensive (MHS) and normotensive (MNS), and (C) Sabra salt-sensitive hypertensive (SBH) and salt-resistant (SBN). Initially, Na(+)-dependent furosemide- or bumetanide-inhibited 86Rb+ fluxes were characterised using Wistar rat microsomes. The latter were partially purified on a metrizamide cushion, and assay conditions were optimized for use with microsomes from the other rats. The major result is that in microsomes from adult Milan hypertensive (MHS) rats the rate of the Na+/K+/Cl(-)-cotransporter mediated 86Rb flux at sub-saturating concentrations of Rb, appears to be significantly greater than in the normotensive (MNS) controls. The effect reflects an increased apparent Rb affinity of the cotransporter in MHS microsomes. There is no difference in maximal rate or in the apparent Na+ activation affinity of the 86Rb+ flux. In addition bumetanide appears to be a somewhat more effective inhibitor in MHS compared to MNS microsomes. The 86Rb+ flux result is compatible with a previous finding that in red cells, Na+/K+ -cotransporter mediated fluxes are increased in MHS compared to MNS. It supports the notion that the Na+/K+/Cl(-)-cotransporter in in both red cells and kidney is a genetic marker for hypertension. It is of interest that apparently more than one Na+ transport system is affected in MHS hypertensive kidneys (a) the Na+/K+/Cl- cotransporter in the thick ascending limb of Henle and (b) the Na+/H+ exchanger and/o a conductive Na(+)-pathway in brush-border membranes from proximal tubule. It is conceivable that in the hypertensive animals a common regulatory pathway (e.g., phosphorylation) or protein (e.g., cytoskeleton) is affected along the length of the nephron. In Sabra SBH and SBN rat microsomes, no difference was found for the 86Rb+ flux via the Na+/K+/Cl- cotransporter (or via a K+ channel).

Erythrocyte adducin differential properties in the normotensive and hypertensive rats of the Milan strain. Characterization of spleen adducin m-RNA

Previous studies have shown that erythrocytes from the Milan hypertensive strain of rats (MHS) differ from erythrocytes from the control normotensive strain (MNS). These differences are determined within the stem cells, are genetically associated with the development of hypertension, and are similar to those found between the tubular cells of the two strains. Moreover they seem to be dependent upon the presence of the membrane skeleton proteins. In this paper we describe our studies aimed at identifying some precise protein difference between the membrane skeletons of the two strains, which may cause the cellular differences described above. Milan hypertensive strain and MNS rats were immunized with ghost or membrane skeleton extracts prepared from the other or their own strains. Only MHS rats immunized with MNS ghost or membrane skeleton extracts produced an antibody against a 105 KD protein in about 95% of the animals. This protein has been identified with the recently described cytoskeletal protein adducin on the following bases: the protein binds calmodulin (CaM) and protein kinase C (PKc) in a Ca2+ dependent way. It also binds phosphatidylserine, is the substrate of exogenous PKc, and finally it is purified by high salt extraction of Triton-X100 insoluble erythrocyte cytoskeletons followed by affinity chromatography on CaM-sepharose. Using this antibody the isolation from a mouse spleen library, the characterization and sequencing of a partial cDNA clone coding for this protein has been carried out. In conclusion adducin may be considered a very useful tool to test the hypothesis that the cellular differences between MHS and MNS may be caused by a difference in a membrane skeleton protein.

A possible primary role for the kidney in essential hypertension

The role of the kidney in "essential" or "genetic" types of hypertension has been evaluated both in a rat model such as the Milan hypertensive strain (MHS) or in humans. In both species, abnormalities of renal function have been demonstrated before the development of hypertension. Moreover hypertension could be "transplanted" with the kidney when kidney cross-transplantation was carried out between MHS and the Milan normotensive strain (MNS). Also in humans, the familiality for hypertension of the donor affected the requirement of antihypertensive therapy of the recipient. Further studies furnished results that were consistent with the hypothesis that a primary increase in Na transport across the tubular cell could be responsible for the pressor effect of the kidney in MHS or in humans. Because many similarities were found between the function of the tubular cell and the red blood cell in MHS, red blood cells were used to gain information about the molecular genetic mechanisms underlying these cellular changes. The results so far obtained showed that red blood cell abnormalities in MHS were genetically determined within the stem cells and genetically associated with the development of hypertension in F2 hybrids obtained by crossing the F1 (MHS X MNS). Moreover, the abnormal Na transport across the cell membrane may be due to an abnormal function of the membrane skeleton proteins. Studies are in progress to evaluate a possible cause-effect relationship between: membrane skeleton protein-ion transport across the cell membrane and the development of hypertension.