Providing safe and effective drug therapy to neonates requires knowledge of the impact of development on the pharmacokinetics and pharmacodynamics of drugs. Although maturational changes are observed throughout childhood, they are most prominent during the first year of life. Several of these processes overlap, making development an extremely dynamic system in the newborn compared with that in infants, children, or adults. Changes in body composition and porportions, liver mass, metabolic activity, and renal function collectively affect the pharmacokinetic behavior of medications. Instead of simply adapting doses by scaling adult or pediatric doses on the basis of a patient's weight and/or body surface area, integrated knowledge of clinical maturation and developmental pharmacology is critical to the safe and effective use of medications in neonates. Unfortunately, the effects of human ontogeny on both pharmacokinetics and pharmacodynamics have not been well established in these early stages of life, and information regarding the influence of developmental changes on the pharmacodynamics of medications is even more limited. Theoretically, age-dependent variations in receptor number and affinity for drugs have significant potential to influence an individual's response to drug therapy. In this review, some of the relevant covariates of pharmacokinetics and pharmacodynamics in neonates are reviewed and illustrated based on the published literature.

The aim is to investigate the association of the delivery mode and vertical transmission of SARS-CoV-2 through the samples of vaginal secretions, placenta, cord blood or amniotic fluid as well as the neonatal outcomes. This cross-sectional study presents an analysis of prospectively gathered data collected at a single tertiary hospital. 63 pregnant women with confirmed COVID-19 participated in the study. Vertical transmission of SARS-CoV-2 was analyzed with RT-PCR tests and blood tests for IgG-M antibodies. All patients were in mild or moderate category for COVID-19. Only one placental sample and two of the vaginal secretion samples were positive for SARS-CoV-2. Except one, all positive samples were obtained from patients who gave birth by cesarean. All cord blood and amniotic fluid samples were negative for SARS-CoV-2. Two newborns were screened positive for COVID-19 IgG-M within 24 hours after delivery, but the RT-PCR tests were negative. A positive RT-PCR result was detected in a newborn of a mother whose placenta, cord blood, amniotic fluid and vaginal secretions samples were negative. He died due to pulmonary hemorrhage on the 11^th day of life. In conclusion, we demonstrated that SARS-CoV-2 can be detectable in the placenta or vaginal secretions of pregnant women. Detection of the virus in the placenta or vaginal secretions may not be associated with neonatal infection. Vaginal delivery may not increase the incidence of neonatal infection, and cesarean may not prevent vertical transmission. The decision regarding the mode of delivery should be based on obstetric indications and COVID-19 severity.

Necrotizing enterocolitis (NEC) is the most common neonatal gastrointestinal emergency, predominantly affecting low-birth weight, premature infants. Early clinical signs of NEC are nonspecific and the laboratory findings are not fully reliable. Its severe morbidities and rapid progression require the application of new biomarkers for early diagnosis and intervention. The complement activation product, C5a (anaphylatoxin) has been reported to be a contributing factor leading to mesenteric ischemia/reperfusion injury which is a predisposing factor in the pathogenesis of NEC. Therefore, our aim was to evaluate the efficacy of serial C5a measurements in the diagnosis and follow-up of NEC. Preterm infants, whose gestational age and weight matched each other, were grouped as controls (n = 23) and NEC (n = 22). Serum levels of C5a, serum amyloid-A (SAA), C-reactive protein (CRP), and interleukin-6 (IL-6) levels were measured on the third day of life for the control group and on the day of diagnosis (1st day), 3rd and 7th days of the NEC group. C5a, SSA, CRP, and IL-6 levels were significantly higher in the NEC patients compared to the control group (P < 0.05) in the follow-up. Additionally, serum levels of C5a were found to be more accurate than the other parameters for the prediction of death and requirement for surgery at the time of diagnosis (P < 0.05). In conclusion, C5a may be useful as a new marker for both diagnosis and follow-up of infants with NEC in combination with clinical and radiographical findings.