[18F]-fluorodeoxyglucose-positron emission tomography findings in protein infants with severe periventricular leukomalacia and hypsarrhythmia

Unraveling the Pathways to Neuronal Homeostasis and Disease: Mechanistic Insights into the Role of RNA-Binding Proteins and Associated Factors

The timing, dosage and location of gene expression are fundamental determinants of brain architectural complexity. In neurons, this is, primarily, achieved by specific sets of trans-acting RNA-binding proteins (RBPs) and their associated factors that bind to specific cis elements throughout the RNA sequence to regulate splicing, polyadenylation, stability, transport and localized translation at both axons and dendrites. Not surprisingly, misregulation of RBP expression or disruption of its function due to mutations or sequestration into nuclear or cytoplasmic inclusions have been linked to the pathogenesis of several neuropsychiatric and neurodegenerative disorders such as fragile-X syndrome, autism spectrum disorders, spinal muscular atrophy, amyotrophic lateral sclerosis and frontotemporal dementia. This review discusses the roles of Pumilio, Staufen, IGF2BP, FMRP, Sam68, CPEB, NOVA, ELAVL, SMN, TDP43, FUS, TAF15, and TIA1/TIAR in RNA metabolism by analyzing their specific molecular and cellular function, the neurological symptoms associated with their perturbation, and their axodendritic transport/localization along with their target mRNAs as part of larger macromolecular complexes termed ribonucleoprotein (RNP) granules.

Asymmetry of cerebral glucose metabolism in very low-birth-weight infants without structural abnormalities

Even when structural abnormalities are not observed on the brain magnetic resonance images (MRI) of very low-birth-weight (VLBW) infants, such infants are at increased risk for poor neurodevelopment. The aim of the present study was to evaluate cerebral glucose metabolism in VLBW infants without apparent structural abnormalities on MRI.

Changes of positron emission tomography in newborn infants at different gestational ages, and neonatal hypoxic-ischemic encephalopathy

Cerebral glucose metabolism was measured by (18)F-fluorodeoxyglucose position emission tomography in infants at different gestational ages and with neonatal hypoxic-ischemic encephalopathy. Thirty-six preterm and term infants at different gestational ages without brain injury were divided into four subgroups: ≤32 weeks (n = 4), 33-34 weeks (n = 5), 35-36 weeks (n = 12), and ≥37 weeks (n = 15). Twenty-four newborn infants with hypoxic-ischemic encephalopathy were divided into three subgroups: mild (n = 13), moderate (n = 7), and severe (n = 4). Cerebral glucose metabolism manifested a trend toward increase, and the structure of cranial (18)F-fluorodeoxyglucose positron emission tomography images became clear with increased gestational age, especially at ≥37 weeks. Uptakes of (18)F-fluorodeoxyglucose in the ≥37-week group were significantly higher than in the ≤32-week group (P < 0.01). Cerebral glucose metabolism changed significantly in neonatal hypoxic-ischemic encephalopathy, and was either unbalanced bilaterally or relatively low at all sites. Moreover, uptakes of (18)F-fluorodeoxyglucose were significantly lower in severe than in mild and medium hypoxic-ischemic encephalopathy (P < 0.05). Cerebral glucose metabolism, as measured by (18)F-fluorodeoxyglucose positron emission tomography, may prove useful for estimating brain development and injury in newborn infants, and its clinical values need further investigation.

Hemodynamics of the posterior cerebral arteries in neonates with periventricular leukomalacia

PURPOSE

The purpose of this study was to evaluate the cerebral blood flow of the posterior cerebral arteries (PCAs) in neonates in relation to the onset of periventricular leukomalacia (PVL).

METHODS

Among 57 low-birth-weight neonates studied, 7 were diagnosed with PVL with cyst formation on sonography and MRI. The mean cerebral blood flow velocity (CBFV) was measured in all the neonates by Doppler sonography through the posterior fontanel separately in the right and left PCA at days 0, 1, 2, 3, 4, 5, 7, 10, 14, 21, 28, 42, 56, and 70 following birth.

RESULTS

In the 7 neonates with PVL the mean CBFV in the right PCA was significantly lower than that in neonates without PVL at days 10, 14, 21, 28, 42, 56, and 70; the mean CBFV in the left PCA of neonates with PVL was significantly lower than that in those without PVL at days 7, 10, 14, 21, 28, 42, 56, and 70. CBFV measured in neonates without PVL exhibited a gradual increase postnatally. In contrast, CBFV values for neonates with PVL plateaued after day 5 or 7.

CONCLUSIONS

The serial measurement of PCA CBFV postnatally may prove useful as a predictor of the development of PVL.