Pre- and postoperative levels of serum brain-derived neurotrophic factor in neonates with congenital heart defects.

BACKGROUND: The objectives of this study were to assess the preoperative and postoperative serum brain- derived neurotrophic factor (BDNF) levels in neonates undergoing surgery for congenital heart defects (CHD). Also to explore the relationship between changes in BDNF levels and the impact of perioperative factors including intraoperative body temperature, aortic cross-clamp time, perfusion time, operation time, inotropic score, vasoactive inotropic score and lactate levels. METHODS: Forty-four patients with CHD and 36 healthy neonates were included in the study. Blood samples for serum BDNF levels were collected three times: preoperatively, and at 24 and 72 hours postoperatively from each patient in the operated group. Additionally, samples were collected once from each individual in the non-operated case group and the control group. Serum BDNF levels were analyzed using the Elabscience ELISA (Enzyme-Linked Immunosorbent Assay) commercial kit. Cranial ultrasonography (USG) was performed on all infants with CHD. Following cardiac surgery, patients underwent second and third cranial USG examinations at 24 and 72 hours postoperatively, respectively. RESULTS: Forty-four consecutive patients with CHD were divided into two groups as follows: the operated group (n=30) and the non-operated group (n=14). Although there were no differences in the baseline serum BDNF levels between the case and control groups, the preoperative serum BDNF levels were significantly lower in the patients operated compared to the non-operated patients. The serum BDNF levels at the 24th hour postoperatively were higher than the preoperative levels. However, no significant correlation was found between the serum BDNF levels at 24 and 72 hours postoperatively as well as the cranial USG findings at corresponding times. CONCLUSIONS: Serum BDNF levels were initially lower in neonates with CHD who underwent surgery, but increased during the early postoperative period. These results suggest that serum BDNF levels are influenced by CHD and the postoperative period.

Medial olivary complex reflex in term newborns with hyperbilirubinemia.

OBJECTIVE: This study aimed to compare the integrity of the efferent auditory pathways of newborns that had high hyperbilirubinemia levels and required treatment due to these and healthy newborns. METHODS: Term-born (37 weeks or later) infants that were brought to the Newborn Polyclinic of the Baskent University Hospital were included in the study. The study included a total of 84 infants including healthy newborns (n = 42) and those that had jaundice and were receiving phototherapy (n = 42). After conducting a general otorhinolaryngology examination on all newborns included in the study, Transient Otoacoustic Emission (TEOAE) test was carried out in the absence and presence of contralateral noise. The obtained contralateral suppression values were compared between the two groups. RESULTS: In the TEOAE test, the responses obtained at 1 kHz in the newborns receiving phototherapy were found to be lower. The difference between the groups was significant (p = 0.038). The rates of suppression presence at 2 kHz, 2.8 kHz and total OAE were found significantly higher (p < 0.05) in the group not receiving phototherapy. Among the phototherapy-receiving infants, the hyperbilirubinemia levels of the infants in whom suppression was obtained in the contralateral suppression test did not show a statistically significant difference in comparison to those in whom suppression was not obtained (p > 0.05). CONCLUSION: Based on the obtained data, hyperbilirubinemia may have a disruptive effect on the efferent auditory system in newborns. Consequently, we are of the opinion that, in addition to hearing screening in risky newborn infants, a MOC suppression test would be useful.

Maternal-fetal proinflammatory cytokine gene polymorphism and preterm birth.

Association between maternal-fetal proinflammatory cytokine genotype and preterm birth was studied. Isolated genomic DNA from maternal and cord blood samples of 100 preterm and 101 term labors were used for TNFα (-238G/A, -308G/A), IL-1α (4845G/T), and IL-1ß (-511C/T) genotyping. TNFα -238 GA genotype in term neonates was significantly higher than the premature neonates (p<0.05). Maternal-fetal TNFα -238 heterozygosity was associated with term labor (p<0.05). TNFα -308 GA and AA genotypes were associated with term labor (mothers and neonates, respectively; p<0.05 and p<0.001). The incidence of term labor was significantly increased in TNFα -308 GA genotype. If a -308GA carrier has a fetus with GG genotype, the incidence of preterm labor increases (p<0.01). The 4845 T allele was significantly higher in preterm mothers and neonates (p<0.001 and p<0.001). The effect of maternal-fetal genotype for the pregnancy outcome reveals that maternal 4845GG and GT genotypes increase term labor incidence, whereas fetal 4845 TT genotype was a significant independent risk factor for preterm birth (p<0.01). IL-1ß -511 TT genotype was significantly higher in preterm neonates. The preterm labor risk was significantly increased in maternal -511 TT genotype and fetal CT genotypes, whereas with maternal -511 CT or TT genotypes or a -511 TT fetus, the incidence of term pregnancy increases (p<0.01).