Evaluation of glucose metabolism in children with growth hormone deficiency during long-term growth hormone treatment.

Growth hormone (GH) affects carbohydrate metabolism through direct negative effect on insulin sensitivity and indirectly, via insulin-like growth factor-1 (IGF-1), which exerts positive insulin-mimetic action. The aim of this retrospective study was to evaluate the influence of long-term GH treatment on glucose homeostasis in 118 children with isolated idiopathic GH deficiency (GHD). Based on this analysis we wanted to determine the usefulness of glycated haemoglobin (HbA1c) and parameters derived from the oral glucose tolerance test (OGTT) in the monitoring of disturbed glucose metabolism during GH treatment and to assess the value of IGF-1 in prediction of those changes. Mean duration of GH treatment was 2.5 ± 1.2 years. Data were analysed in the whole group and according to baseline pubertal status. Significant increases in insulin concentrations, both fasting and during the OGTT, accompanied by a significant increase in fasting glucose and unchanged glucose concentrations during the OGTT, were found after the initiation of GH treatment. HbA1c did not change significantly during GH treatment in comparison to baseline values and remained normal, even in patients with impaired fasting glucose (IFG) or impaired glucose tolerance (IGT) found during GH treatment. Changes in glucose metabolism observed after the onset of GH treatment were related to increment in IGF-1 SDS and to GH doses. Significant associations between changes in IGF-1 SDS in the first year of GH treatment and some of the glucose metabolism parameters evaluated after the first, the second and the third year of GH treatment were also confirmed in multiple regression analysis after taking the GH dose into consideration. All cases of IFG and/or IGT detected during GH treatment are reversible after dietary intervention, independently of pubertal status, and do not lead to diabetes mellitus.

Pro- and antiangiogenic markers in patients with pulmonary complications of systemic scleroderma.

Systemic sclerosis (SSc) is an autoimmune disorder characterized by skin and internal organs fibrosis and concomitant vascular abnormalities. Although SSc is considered mainly fibrosing disease, underlying vascular pathology plays a fundamental role in its pathogenesis. We have focused on positive and negative serum markers of angiogenesis and fibrosis (pigment epithelium-derived factor [PEDF], vascular endothelial growth factor [VEGF], and soluble VEGF receptor [sVEGFR]), in progressive SSc patients at baseline and after follow-up in relation to cardiopulmonary complications (systemic hypertension [HT], pulmonary arterial hypertension [PAH] and pulmonary fibrosis [PF]). VEGF and PEDF but not sVEGFR were reciprocally regulated in SSc progression. Moreover, VEGF/PEDF ratio significantly increased during follow up suggesting that it might be used as a biomarker of disease progression. No correlation between the studied markers and cardiopulmonary complications was observed. In conclusion, VEGF and PEDF level, and the VEGF/PEDF ratio are significantly changed in the course of SSc progression and these markers can be used to assess SSc activity.

Immunological Characteristics of Children with Hashimoto's Autoimmune Thyroiditis.

The main cause of autoimmune thyroiditis of Hashimoto's type (HT) is a pathological immune response to thyroid antigens. The aim of the study was to present clinical characteristics and immune profile of children with HT. Ninety five children were examined: 45 with HT (age: 8-18 years) and 50 healthy age-matched controls. The peripheral blood mononuclear cells' (PBMC) phenotype was evaluated using a Beckman Coulter flow cytometer with the following monoclonal antibodies: CD4-FITC, CD28-PC5, CD152-PE and CD8-FITC, CD28-PC5, CD152-PE. The thyroid stimulating hormone, thyroid hormones, and antibodies against thyroid peroxidase (TPO) and thyroglobulin (TG) were evaluated by a microparticle enzyme immunoassay. We found that goiter was present in 53% of children, the thyroid had an increased density in palpation in 98%, and hypothyroidism was diagnosed in 11% of HT patients. The number of CD152+ was lower in HT than in healthy children (p<0.05). CD4+ and CD8+ PBMC subsets did not differ between the groups at baseline. After stimulation with phytohemagglutinine (PHA), CD4+ cells decreased in healthy controls and remained constant in HT children. Anti-TPO and anti-TG antibodies were higher in children with a lower percentage of CD152+. No other markers correlated with the immunological profile of PBMC. The percentages of CD4+ and CD152+ negatively correlated with the anti-TG concentration. We conclude that children with HT have a different PBMC profile than healthy children and show a different pattern of response to stimulation.

Flow cytometry in detection of abnormalities of natural killer cell.

The population of natural killer (NK) cells is very heterogeneous and plays a role in the immune system. Several NK cells subpopulations are recognized, differing in phenotype, cytokine release and cytotoxic ability. Different expression of biologically relevant molecules on the surface of NK cells may indicate their multiple functions. The activity of NK cells has mainly to do with their cytotoxic nature. A complete analysis of NK cells function requires application of many tests because a defect may be present at different stages of the cytotoxic process, from signal transduction through lysosome degranulation to target cells destruction. Flow cytometry is actually one of the best methods for the identification of NK cells and tracking their defects.

Leptin receptors.

Leptin or obesity receptor (Ob-R) is a member of class I cytokine receptor family. Ob-R, expressed in six isoforms, is the product of alternative RNA splicing of db gene. According to its structural differences, the receptor's isoforms are divided into three classes: long, short, and secretory isoforms. A long, fully active isoform of Ob-Rb is expressed mainly in the hypothalamus, where it takes part in energy homeostasis and in the regulation of secretory organs' activity. Ob-Rb is also present on all types of immune cells, involved in innate and adaptive immunity. Short leptin isoforms (Ob-Ra, Ob-Rc, Ob-Rd, and Ob-Re) that contain box 1 motif are able to bind JAK kinases (Janus kinases) as well as to activate some other signal transduction cascades. A soluble isoform (Ob-Re) can regulate serum leptin concentration and serve as a carrier protein delivering the hormone to its membrane receptors and is able to transduce the signal into the cell. JAK/STAT pathway plays the major role in leptin signal transduction through membrane receptors. Among all Ob-R isoforms, only full-length isoform (Ob-Rb) is able to fully transduce activation signal into the cell.

Proinflammatory cytokines Il-6 and TNF-α and the development of inflammation in obese subjects.

BACKGROUND: The development of obesity and related disorders, e.g., type II diabetes (T2D), hypertension, and metabolic disturbances is strongly related to increased levels in proinflammatory cytokines (IL-1, IL-6, and TNF-α). Both IL-6 and TNF-α are secreted by adipocytes and their concentration correlates with the percentage and distribution of fat tissue in the body. Both cytokines are the main factors responsible for the induction of acute phase proteins production (e.g., CRP) and to inflammatory state. OBJECTIVE: To compare of TNF-α and IL-6 concentrations in serum from obese subjects with those in subjects with normal BMI and to analyze the relation between TNF-α, IL-6, BMI and the inflammatory state as measured by the level of CRP. MATERIAL AND METHODS: The study included 80 obese subject (54 males and 26 females) BMI >25 kg/m⊃2. A control group consisted of 53 healthy subjects (24 males and 29 females) with BMI <25 kg/m⊃2. To determine the blood plasma concentration of IL-6 and TNF, commercial ELISA assay kits were used. RESULTS: The concentration of IL-6 was lower in the control compared with the obese patients, but a significance difference concerned only female subjects (P = 0.001). TNF-α concentration was significantly higher in all obese subjects (P<0.001). A higher level of this cytokine was also found in patients with obesity suffering from T2DM. A positive correlation was present between IL-6 and TNF-α concentrations. Only did the IL-6 level correlate with the concentration of CRP in serum. CONCLUSIONS: The study confirmed that increased inflammatory cytokines lead to the persistence of inflammation in obese subjects. However, some other factors, such as gender, may contribute to the development of obesity-related inflammatory states.

Evaluation of T regulatory cell apoptosis in children with newly recognized type 1 diabetes mellitus.

BACKGROUND: Type 1 diabetes is a metabolic disease characterized by an autoimmune, T-cell dependent destruction of insulin producing pancreatic beta cells. T regulatory cells (Tregs) are critical regulators of immune tolerance. OBJECTIVE: The aim of the study was to investigate CD4 +CD25 highFoxP3 cell apoptosis in the peripheral blood of children with newly diagnosed type 1 diabetes mellitus. METHODS: 34 children (15 girls and 19 boys) with new onset of type 1 diabetes mellitus, of the mean age 6.9 ±5.2 (range 0.9-17.5 yr) and 18 healthy controls (8 girls, 10 boys) of the mean age 7.3 ±4.6 (1.9-17.5 yr) were included into the study. Flow cytometric analysis of Tregs was performed using the following markers: anti-CD4, anti-CD25 and transcription factor FoxP3. Apoptosis was measured using anti-active caspase-3 monoclonal antibody. The percentage of apoptotic cells was measured within CD4 +CD25 highFoxP3+ cells. RESULTS AND CONCLUSION: There was no statistically significant difference in the percentage of apoptotic CD4 +CD25 highFoxP3 + cells between children with diabetes and healthy subjects; the median value 0 (range 0-26.8) vs. 0 (range 0-2.6), respectively (P = 0.302). Further, clinical studies on a larger cohort of diabetic children are needed to evaluate T regulatory cell apoptosis, especially for future immune-based therapy.

Influence of proinflammatory cytokine gene polymorphism on childhood obesity.

BACKGROUND: Obesity development is a complex process which can be influenced by genetic predisposition modified by environmental factors. Nowadays, the problem of overweight and obesity, including related complications, occurs in increasingly younger children. Thus, there is a need for new genetic markers of increased risk of excessive body mass. OBJECTIVE: The aim of the present study was to examine the relation between polymorphisms located in promoter regions of IL-1beta, IL-6, and TNF-alpha genes and obesity development in children. Fifty obese and 55 normal weighing children were enrolled into the study. Genetic examination was performed using PCR-RFLP technique. RESULTS: We found a relation between G174C polymorphism in IL-6 gene and G308A in TNF-alpha gene with the occurrence of obesity. Allele A in G308A was more frequent in the obese group than in the control one (P=0.04). The presence of allele C in promoter region of IL-6 gene was more frequent in obese children and connected with a statistically significant increase in the sum of 10 skin fold thickness measurements (P=0.03). CONCLUSIONS: The polymorphism C3954T in IL-1beta gene showed no such relation. The examined polymorphisms of proinflammatory cytokines play a role in the regulation of body mass through their influence on metabolism and energetic homeostasis.

Effect of surface finish on the osseointegration of laser-treated titanium alloy implants.

It was the purpose of this study to examine the osseointegration of laser-textured titanium alloy (Ti6Al4V) implants with pore sizes of 100, 200, and 300 microm, specifically comparing 200-microm implants with polished and corundum-blasted surfaces in a rabbit transcortical model. Using a distal and proximal implantation site in the distal femoral cortex, each animal received all four different implants in both femora. The bone-implant interface and the newly formed bone tissue within the pores and in peri-implant bone tissue were examined 3, 6, and 12 weeks post-implantation by static and dynamic histomorphometry. Here we show that additional surface blasting of laser-textured Ti6Al4V implants with 200-microm pores resulted in a profound improvement in osseointegration, 12 weeks postimplantation. Although lamellar bone formation was found in pores of all sizes, the amount of lamellar bone within pores was linearly related to pore size. In 100-microm pores, bone remodeling occurred with a pronounced time lag relative to larger pores. Implants with 300-microm pores showed a delayed osseointegration compared with 200-microm pores. We conclude that 200 microm may be the optimal pore size for laser-textured Ti6Al4V implants, and that laser treating in combination with surface blasting may be a very interesting technology for the structuring of implant surfaces.

Congenital ophthalmoplegia and school achievement: a case study.

A 6 1/2-year-old boy with Moebius' syndrome, with severely restricted horizontal eye movements, was found to have the visuo-motor integration of a child of three years (IQ equivalent 41) and the perceptual development of a child of four years 10 months (perceptual quotient 68). Cognitive assessment revealed functioning in the low dull-normal range of ability (IQ equivalent 83). Achievement in arithmetic and reading was found to be at late kindergarten and early first-grade levels respectively (IQ equivalents 83 and 92). Thus the boy's achievement was in line with his cognitive ability and greater than 1 S.D. above his visual-perception and visuo-motor development. The results of this study replicate the findings of Kalverboer et al. (1970) on a 12-year-old boy with Moebius' syndrome and add to a growing body of evidence which does not support the current emphasis on visuo-motor development and training in the diagnosis and remediation of learning difficulties.