Maha H. Mohamed

Vascular endothelial growth factor in neonates with perinatal asphyxia.

BACKGROUND Vascular endothelial growth factor (VEGF) is a polypeptide growth factor that is activated by tissue hypoxia. The role of VEGF in perinatal asphyxia in human neonates is yet to be clarified. In infants who develop moderate to severe acute hypoxic ischemic encephalopathy (HIE) it is crucial to clearly understand physiologic and biochemical changes that accompany HIE before a novel treatment can be developed. OBJECTIVES To assess VEGF in cord blood of infants suffering from perinatal asphyxia, and to determine whether an association exists between increased concentrations of VEGF and the risk for development of encephalopathy. STUDY DESIGN We prospectively studied 40 full term infants; of them 20 infants suffered from perinatal asphyxia, and 20 control infants of comparable age and sex. We obtained cord blood samples from all subjects immediately after delivery. Neurological examination and grading of HIE were performed during the first day of life. RESULTS Birth weight, gestational age and gender did not differ between the control (n=20) and asphyxia (n=20) groups. Within the asphyxia group four infants developed HIE; one with severe encephalopathy who died shortly after birth, while the other three infants had moderate HIE. Concentrations of VEGF were increased in infants with asphyxia when compared to controls (P0.001). Within the asphyxia group, infants with HIE had significantly increased concentrations of VEGF when compared to non-HIE asphyxiated infants (P=0.008). In the logistic regression model, VEGF inversely correlated with pH and PO(2) in cord blood, and Apgar scores at 1min, while it did not associate with gestational age and birth weight. CONCLUSIONS This study indicates that VEGF is increased in cord blood of neonates following birth asphyxia, and that VEGF is specifically most increased in infants who later developed encephalopathy. Further studies are required to determine the role of VEGF in brain insult. Such studies will help determine whether a therapeutic role for VEGF or VEGF inhibitors can exist for HIE infants.

Cord blood resistin and adiponectin in term newborns of diabetic mothers.

Introduction Adipose tissue can release hormones into the blood stream in response to specific extracellular stimuli or changes in metabolic status. Resistin, an adipose-secreted factor, is primarily involved in the modulation of insulin sensitivity and adipocyte differentiation. Adiponectin, an adipocyte-specific hormone with insulin sensitizing, anti-inflammatory and anti-atherogenic effects, is reduced in obesity and type II diabetes. The aim of the study was to assess the influence of maternal pre-existing diabetes on cord blood resistin and adiponectin at birth in relation to neonatal anthropometric parameters and cord blood insulin levels. Material and methods A total of 60 term newborns were prospectively enrolled and categorized into three groups: 20 were macrosomic infants of pre-gestational diabetic mothers (group I), 20 were non-macrosomic infants of pre-gestational diabetic mothers (group II) and 20 were healthy non-macrosomic infants born to non-diabetic mothers serving as controls (group III). Infants’ anthropometric indices were recorded. Cord blood samples for glucose, insulin, resistin and adiponectin assay, together with maternal glycosylated haemoglobin were obtained. Results Serum insulin was increased while resistin and adiponectin were significantly decreased in infants of diabetic mothers (IDMs) compared to the control group. Serum glucose, insulin, resistin and adiponectin were comparable in group I and II. Cord serum resistin correlated positively with cord blood glucose in IDMs in both macrosomic and non-macrosomic groups. Cord serum insulin correlated positively with triceps skinfold thickness in all studied neonates. Cord serum resistin and adiponectin showed no correlation with neonatal anthropometric indices. Multiple regression analysis demonstrated that insulin, resistin and adiponectin together were highly correlated with birth weight, with adiponectin as the one responsible for this positive correlation. Conclusions Infants of diabetic mothers had elevated levels of cord serum insulin and suppressed levels of cord serum resistin and adiponectin, suggesting that the regulation of these metabolic pathways is probably operational before birth. Levels were comparable in both macrosomic and non-macrosomic neonates.

Predictive value of vascular endothelial growth factor in preterm neonates with intraventricular haemorrhage

Objective: Intraventricular haemorrhage (IVH) is a major problem in premature infants. Our objective is to assess the early predictive value of vascular endothelial growth factor (VEGF) for development of IVH and management of its squeal in preterm neonates. Methods: We prospectively studied 150 preterm neonates (PT) less than 34 weeks gestation. Fifty of them completed the study. 30/50 developed IVH during follow up, and 20 did not. First 24 hours, and 3rd day serum samples were collected. Cerebrospinal fluid (CSF) samples were withdrawn for 10 IVH patients. Results: Serum VEGF; both samples were increased in IVH compared to non-IVH group (P = 0.001). PHVD-group (n = 10) had higher VEGF in both samples than resolved IVH (P = 0.004), (P = 0.005). While, VEGF increased in the IVH group 2nd sample compared to 1st (P = 0.000), it decreased in non-IVH group, P = 0.033). Each 1 unit increase in 1ST VEGF increased the risk of occurrence of IVH by 1.6%. 3rd day VEGF at a cut-off value of 135 pg/ml is 96% sensitive and 100% specific to predict PHVD. Serum VEGF inversely correlated with TLC, pH, PO2 and HCO3, and positively correlated with PCo2 and FiO2. Conclusion: Serum VEGF predicts development of IVH and PHVD in PT neonates. Also, high CSF level of VEGF could predict the need for permanent shunt placement.

Effect of intrauterine growth pattern on serum visfatin concentrations in full-term infants at birth and at 6 months of life

OBJECTIVE Visfatin is a hormone discovered in fat cells and is directly related to diabetes. We aimed to investigate the relationship between intrauterine growth pattern and serum visfatin concentrations in full-term infants at birth and at 6 months of life. METHODS Cord blood visfatin concentrations were assessed in 90 full-term neonates enrolled into; Group I: 30 appropriate for gestational age (AGA) neonates to healthy mothers, Group II: 30 intra-uterine growth restricted (IUGR) neonates, 19 were born to mothers with pre-eclampsia, Group III: 30 large for gestational age (LGA) neonates, 16 were infants of diabetic mothers (IDMs). Neonates were followed up at six months of age for visfatin concentrations. RESULTS Cord blood visfatin concentrations were increased in IUGR compared to AGA group (p = 0.002). Cord blood visfatin concentrations were increased in LGA compared to AGA and IUGR groups (P <  0.001, P <  0.001). Cord blood visfatin concentrations were positively correlated to birth weight in AGA, LGA groups (r = 0.39, p = 0.045, r = 0.449, p = 0.013 respectively). Visfatin concentrations in neonates born to mothers with pre-eclampsia and IDMs were higher than in those born to mothers without pre-eclampsia and to non-diabetic mothers (p = 0.040, p = 0.002 respectively). At six months, serum visfatin concentrations decreased compared to cord blood visfatin concentrations in IUGR and LGA groups (p <  0.001). Levels in LGA were still higher than IUGR (p = 0.004). Serum visfatin concentrations were positively correlated to cord visfatin in IUGR neonates (r = 0.497, p = 0.005). CONCLUSION Cord blood visfatin concentrations were increased in LGA and IUGR neonates. At six months, serum visfatin concentrations decreased compared to cord blood visfatin concentrations in LGA and IUGR groups, still higher in the former than the latter.

Resistin in infants of diabetic mothers: relation to insulin and anthropometry

ObjectiveTo determine the effect of maternal diabetes on serum resistin and insulin in term neonates and to correlate their level with neonatal anthropometric measures. Materials and methodsSixty neonates were recruited from the Obstetrics and Gynecology Hospital and Ain Shams University Hospital. These neonates were divided into three groups. Group 1 included 20 full-term macrosomic neonates of diabetic mothers. Group 2 included 20 full-term nonmacrosomic neonates of diabetic mothers. Group 3 included 20 healthy full-term nonmacrosomic neonates of nondiabetic mothers serving as a control. For all neonates, complete medical and obstetric history was taken. Thorough clinical examination and anthropometric measurements were carried out. Maternal glycosylated hemoglobin was measured. Cord blood was withdrawn to measure random blood sugar, serum insulin, and serum resistin. ResultsAll skin-fold thicknesses were significantly higher in infants of diabetic mothers (IDMs) than control (P<0.001). Serum insulin was significantly higher and serum resistin was significantly lower in IDMs than in the control group (P<0.001 and 0.005, respectively). Serum resistin correlated positively with cord blood glucose in IDMs of both macrosomic (r=0.522, P=0.01) and nonmacrosomic groups (r=0.462, P=0.04). A highly significant positive correlation was found between maternal glycosylated hemoglobin and neonatal birth weight, supine length, and skin-fold thickness in group 1 (macrosomic) IDM. ConclusionIt was concluded that IDMs had elevated levels of serum insulin and suppressed levels of serum resistin, suggesting that these hormones are probably operational before birth.

Immobilization of Co(II) ions in cement pastes and their effects on the hydration characteristics

Abstract The immobilization of Co (II) in various cement matrices was investigated by using the solidification/stabilization (S/S) technique. The different cement pastes used in this study were ordinary Portland cement in absence and presence of water reducing- and water repelling-admixtures as well as blended cement with kaolin. Two ratios of Co (II) were used (0.5% and 1.0% by weight of the solid binder). The hydration characteristics of the used cement pastes were tested via the determination of the combined water content, phase composition and compressive strength at different time intervals up to 180 d. The degree of immobilization of the added heavy metal ions was evaluated by determining the leached ion concentration after time intervals extended up to 180 d. The leachability experiments were carried out by using two modes: the static and the semi-dynamic leaching processes. It was noticed that the concentration of the leached Co 2+ ions in the static mode of leachability was lower than the solubility of its hydroxide in all the investigated cement pastes.