Abnormal asymmetries in subcortical brain volume in schizophrenia.

Subcortical structures, which include the basal ganglia and parts of the limbic system, have key roles in learning, motor control and emotion, but also contribute to higher-order executive functions. Prior studies have reported volumetric alterations in subcortical regions in schizophrenia. Reported results have sometimes been heterogeneous, and few large-scale investigations have been conducted. Moreover, few large-scale studies have assessed asymmetries of subcortical volumes in schizophrenia. Here, as a work completely independent of a study performed by the ENIGMA consortium, we conducted a large-scale multisite study of subcortical volumetric differences between patients with schizophrenia and controls. We also explored the laterality of subcortical regions to identify characteristic similarities and differences between them. T1-weighted images from 1680 healthy individuals and 884 patients with schizophrenia, obtained with 15 imaging protocols at 11 sites, were processed with FreeSurfer. Group differences were calculated for each protocol and meta-analyzed. Compared with controls, patients with schizophrenia demonstrated smaller bilateral hippocampus, amygdala, thalamus and accumbens volumes as well as intracranial volume, but larger bilateral caudate, putamen, pallidum and lateral ventricle volumes. We replicated the rank order of effect sizes for subcortical volumetric changes in schizophrenia reported by the ENIGMA consortium. Further, we revealed leftward asymmetry for thalamus, lateral ventricle, caudate and putamen volumes, and rightward asymmetry for amygdala and hippocampal volumes in both controls and patients with schizophrenia. Also, we demonstrated a schizophrenia-specific leftward asymmetry for pallidum volume. These findings suggest the possibility of aberrant laterality in neural pathways and connectivity patterns related to the pallidum in schizophrenia.

Increased digitalis-like immunoreactive substances in neonatal plasma measured using fluorescence polarization immunoassay.

OBJECTIVE: To better define the reported increased digitalis-like immunoreactive substances (DLIS) in neonatal plasma, we studied the relation among plasma DLIS level, blank intensity (BLK-I) value at FPIA measurement and plasma total bilirubin level. METHODS: The DLIS levels were measured in 10 neonates with or without jaundice and 10 infants in good health, using fluorescence polarization immunoassay (FPIA) and microparticle enzyme immunoassay (MEIA). BLK-I value and plasma total bilirubin level were also measured simultaneously. RESULTS: In neonates with jaundice, DLIS using FPIA, BLK-I and total bilirubin level were 0.58 +/-0.13 ng/mL, 2598 +/- 408, and 17.98 +/- 1.13 mg/dL, respectively, before phototherapy, and 0.33 +/-0.06 ng/mL, 1886 +/- 237, and 15.16 +/- 2.07 mg/dL after phototherapy. Corresponding values in neonates without jaundice were (DLIS: 0.34 +/-0.04 ng/mL; BLK-I: 1,764 +/- 278; total bilirubin: 10.37 +/- 4.54 mg/dL); in healthy infants (0.12 +/-0.06 ng/mL, 400.7 +/- 4.6 and 0.42 +/- 0.13 mg/dL, respectively) and in healthy volunteers (0.10 +/-0.07 ng/mL, 403.1 +/- 8.4, and 0.58 +/- 0.30 mg/dL, respectively). Using MEIA, DLIS was not detected in 10 neonates, 10 infants and 20 healthy volunteers. CONCLUSIONS: A fluorescent compound related to bilirubin increased the BLK-I value in the measurement of neonatal plasma using FPIA. The fluorescence was not the result of endogenous digitalis-like factors.

N-methyl-D-aspartate receptor participates in neuronal transmission of photic information through the retinohypothalamic tract.

In order to assess the hypothesis that excitatory amino acids (EAA) are involved in the transmission of light information from retina to suprachiasmatic nucleus (SCN) and pineal via the retinohypothalamic tract (RHT), we have determined whether injections of EAA agonist into SCN could mimic the suppressive effects of light pulse on pineal melatonin production, and whether pretreatment with antagonists could block effects of light pulse in the intact rat. Injection of the EAA agonist N-methyl-D-aspartate (NMDA: 1.0 mM; 0.5 microliter) into the SCN suppressed plasma melatonin level and pineal N-acetyltransferase activity. The pretreatment with D-aminophosphonovalerate (D-APV: 2.5 or 10 mM; 2.0 microliters) or N-[1-(2-thienyl)-cyclohexyl]-piperidine (10 mM; 2.0 microliters) which are NMDA type receptor antagonists blocked the suppressive effect of the light pulse (3.0 Ix for 2 min), while the pretreatment with neither vehicle nor L-APV (optic isomer APV: 10 mM; 2.0 microliters) could block the effect of light. Alpha-D-glutamyl-amino-methylsulfonate (10 mM; 2.0 microliters or 25 mM; 2.0 microliters), which is a relative antagonist for non-NMDA type receptor, had no effect, either. These results suggest that EAA is involved in the transmission of light information through RHT and that in rat SCN EAA operates at the NMDA type receptor on the SCN.