A New Fluorescent Sensor Based on 1H-pyrazolo[3,4-b]quinoline Skeleton. Part 2

A novel fluorescent dye bis-(pyridin-2-yl-methyl)-(1,3,4-triphenyl-1H-pyrazolo[3,4-b]quinolin-6-ylmethyl)-amine (P1) has been synthesized and investigated by means of steady state and time-resolved fluorescence techniques. This compound acts as sensor for fluorescence detection of small inorganic cations (lithium, sodium, barium, magnesium, calcium, and zinc) in highly polar solvents such as acetonitrile. The mechanism which allows application of this compound as sensor is an electron transfer from the electron-donative part of molecule (amine) to the acceptor part (pyrazoloquinoline derivative), which is retarded upon complexation of the electro-donative part by inorganic cations. The binding constants are strongly dependent on the charge density of the analyzed cations. The 2/1 complexes of P1 with Zn++ and Mg++ cations posses large binding constants. Moreover, in the presence of these cations a significant bathochromic shift of fluorescence is observed. The most probable explanation of such behaviour is the formation of intramolecular excimer. This is partially supported by the quantum chemical calculations

The effect of enteral and parenteral feeding on secretion of orexigenic peptides in infants

<p>Abstract</p> <p>Background</p> <p>The feeding in the first months of the life seems to influence the risks of obesity and affinity to some diseases including atherosclerosis. The mechanisms of these relations are unknown, however, the modification of hormonal action can likely be taken into account. Therefore, in this study the levels of ghrelin and orexin A - peripheral and central peptide from the orexigenic gut-brain axis were determined.</p> <p>Methods</p> <p>Fasting and one hour after the meal plasma concentrations of ghrelin and orexin were measured in breast-fed (group I; n = 17), milk formula-fed (group II; n = 16) and highly hydrolyzed, hypoallergic formula-fed (group III; n = 14) groups, age matched infants (mean 4 months) as well as in children with iv provision of nutrients (glucose - group IV; n = 15; total parenteral nutrition - group V; n = 14). Peptides were determined using EIA commercial kits.</p> <p>Results</p> <p>Despite the similar caloric intake in orally fed children the fasting ghrelin and orexin levels were significantly lower in the breast-fed children (0.37 ± 0.17 and 1.24 ± 0.29 ng/ml, respectively) than in the remaining groups (0.5 ± 0.27 and 1.64 ± 0.52 ng/ml, respectively in group II and 0.77 ± 0.27 and 2.04 ± 1.1 ng/ml, respectively, in group III). The postprandial concentrations of ghrelin increased to 0.87 ± 0.29 ng/ml, p < 0.002 and 0.76 ± 0.26 ng/ml, p < 0.01 in groups I and II, respectively as compared to fasting values. The decrease in concentration of ghrelin after the meal was observed only in group III (0.47 ± 0.24 ng/ml). The feeding did not influence the orexin concentration. In groups IV and V the ghrelin and orexin levels resembled those in milk formula-fed children.</p> <p>Conclusion</p> <p>The highly hydrolyzed diet strongly affects fasting and postprandial ghrelin and orexin plasma concentrations with possible negative effect on short- and long-time effects on development. Also total parenteral nutrition with the continuous stimulation and lack of fasting/postprandial modulation might be responsible for disturbed development in children fed this way.</p

Gastric Lipase Secretion in Children with Gastritis

Gastric lipase is one of the prepancreatic lipases found in some mammalian species and in humans. Our knowledge of the hormonal regulation of gastric lipase secretion in children and adolescents is still very limited. The aim of this study was to compare the activity of human gastric lipase (HGL) in gastric juice in healthy adolescents and in patients with gastritis. The adolescents were allocated to three groups: the first including patients with Helicobacter pylori gastritis (HPG; n = 10), the second including patients with superficial gastritis caused by pathogens other than H. pylori (non-HPG; n = 14) and the control group including healthy adolescents (n = 14). Activity of HGL was measured in gastric juice collected during endoscopy. Plasma concentrations of cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) were measured in all adolescents. Activity of HGL in the non-HPG group was significantly lower than in the HPG group (p < 0.005) and the control group (p < 0.005). Mean plasma GIP levels in the control group were lower than in the non-HPG group (p < 0.003) and the HPG group (p < 0.01). We conclude that the regulation of HGL secretion by GLP-1 and CCK is altered in patients with gastritis. Moreover, GIP is a potent controller of HGL activity, both in healthy subjects and in patients with gastritis

Plasma levels of leptin and soluble leptin receptor and polymorphisms of leptin gene -18G > A and leptin receptor genes K109R and Q223R, in survivors of childhood acute lymphoblastic leukemia

<p>Abstract</p> <p>Background</p> <p>Approximately 20% of children and adolescents in Europe are overweight. Survivors of pediatric acute lymphoblastic leukemia (ALL) are at increased risk of overweight and obesity. The purpose of this study was to assess leptin and leptin soluble receptor levels, as well as polymorphisms of selected genes in survivors of pediatric ALL, and the influence of chemo- and radiotherapy on development of overweight in the context of leptin regulation.</p> <p>Methods</p> <p>Eighty two patients (55% males), of median age 13.2 years (m: 4.8 years; M: 26.2 years) were included in the study. The ALL therapy was conducted according to modified Berlin-Frankfurt-Munster (BFM; n = 69) regimen or New York (n = 13) regimen. In 38% of patients cranial radiotherapy (CRT) was used in median dose of 18.2Gy (m: 14Gy; M: 24Gy). Median age at diagnosis was 4.5 (m: 1 year; M: 16.9 years) and median time from completion of ALL treatment was 3.2 years (m: 0.5 year; M: 4.3 years). Patients with BMI ≥85 percentile were classified as overweight. Correlation of plasma levels of leptin and leptin soluble receptor, and polymorphisms of leptin gene -18G > A, leptin receptor genes K109R and Q223R, and the overweight status were analyzed in relation to gender, intensity of chemotherapy (high intensity vs. standard intensity regimens) and to the use of CRT.</p> <p>Results</p> <p>Significant differences of leptin levels in patients treated with and without CRT, both in the entire study group (22.2+/- 3.13 ng/ml vs. 14.9+/-1.6 ng/ml; p < 0.03) and in female patients (29.9+/-4.86 ng/ml vs. 16.9+/-2.44 ng/ml; p = 0.014), were found. Significant increase of leptin levels was also found in overweight patients compared to the non-overweight patients in the entire study group (29.2+/-2.86 ng/ml vs. 12.6+/-1.51 ng/ml; p < 0.0001), female patients (35.4+/-6.48 ng/ml vs. 18.4+/-2.5 ng/ml; p = 0.005), and male patients (25.7+/-2.37 ng/ml vs. 6.9+/-0.95 ng/ml; p < 0.0001). Negative correlation was observed for plasma levels of soluble leptin receptor and overweight status, with significant differences in overweight and non-overweight patients, both in the entire study group (18.2+/-0.75 ng/ml vs. 20.98+/-0.67 ng/ml; p = 0.017) and in male patients (18.2+/-1.03 ng/ml vs. 21.8+/- 1.11 ng/ml; p = 0.038). Significant (p < 0.05) negative correlation was found between leptin and leptin receptor levels in the entire group (correlation coefficient: 0.393) and in both gender subgroups (correlation coefficient in female patients: -0.427; in male patients: -0.396).</p> <p>Conclusions</p> <p>The prevalence of overweight in our cohort was higher than in general European population (31% vs 20%) and increased regardless of the use of CRT. Leptin and leptin receptor levels may be used as useful markers of high risk of becoming overweight in ALL survivors, particularly in females treated with CRT. Polymorphisms of leptin gene -18G > A and leptin receptor genes K109R and Q223R were not associated with overweight status in ALL survivors.</p