Abstract Objective Neuroimaging studies showed abnormalities in frontal white matter (WM) in schizophrenia that were associated with clinical symptoms. Previously, we reported ultrastructural ...alterations of myelinated fibers and reduction in the numerical density of oligodendrocytes in BA 10 WM in patients with schizophrenia. We aimed to perform a qualitative and morphometric study of the ultrastructure of oligodendrocytes in BA 10 WM in schizophrenia and in normal controls. Methods The study was performed using electron microscopy and morphometry. Size, volume density (Vv) and the number (N) of organelles of oligodendrocytes were estimated in 21 patients with schizophrenia and 20 normal controls. The data were examined using the Kolmogorov–Smirnov test for normality. Pearson correlation analysis was performed to assess possible correlations between the parameters measured and age, post-mortem interval, neuroleptic treatment and duration of the disease. Comparisons between the schizophrenia patients and controls were performed using ANCOVA tests. Results We found oligodendrocyte swelling, vacuolation, paucity of ribosomes and mitochondria and accumulation of lipofuscin granules in schizophrenia as compared to controls. Morphometry detected a significant reduction in Vv and N of mitochondria and the increase in Vv and N of lipofuscin granules and vacuoles in oligodendrocytes in the schizophrenic group as compared to controls. Conclusion Alterations of oligodendrocytes in schizophrenia provide evidence for the disturbance of their energy, lipid and protein metabolism in prefrontal WM. Oligodendrocyte abnormalities might disturb axonal integrity and circuitry and contribute to the pathophysiology of schizophrenia.
This study addressed the question of whether the interaction between neurons and satellite microglia (SatMg) is abnormal in schizophrenia. SatMg-neuron communication at direct contacts between ...neuronal soma is essential for neuroplasticity as SatMg can regulate neuronal activity. A postmortem ultrastructural morphometric study was performed to investigate SatMg and adjacent neurons in layer 5 of the prefrontal cortex in 21 cases of schizophrenia and 20 healthy controls. Density of SatMg was significantly higher in the young schizophrenia group and in the group with illness duration ≤ 26 years as compared to controls. We found lower volume fraction (Vv) and the number (N) of mitochondria and higher Vv and N of lipofuscin granules and vacuoles in endoplasmic reticulum in SatMg in the schizophrenia compared to the control brain. These changes progressed with age and illness duration. A significantly higher soma area and Vv of vacuoles of endoplasmic reticulum were revealed in neurons in schizophrenia as compared to controls. Negative significant correlations between N of vacuoles in neurons and N of mitochondria in SatMg were found in the control group but not in the schizophrenia group. Area of vacuole in neurons was significantly positively correlated with Vv and area of mitochondria in SatMg in the control group and negatively in the schizophrenia group. Correlation coefficients between these parameters differed significantly between the groups. These results indicate disturbed SatMg-neuron interactions in the schizophrenia brain and suggest a key role of mitochondrial abnormalities in SatMg in these disturbances.
Objectives.
To study the ultrastructure of microglia in contact with oligodendrocytes in the white matter of the prefrontal cortex in continuous schizophrenia (CS) in comparison with controls and ...paroxysmal progressive schizophrenia (PPS) and to analyze correlations between the parameters of microglia and previously studied oligodendrocytes in controls and different types of schizophrenia.
Materials and methods
. Electron microscopic morphometric studies of microglia in contact with oligodendrocytes in the white matter of the prefrontal cortex (Brodmann’s area 10) were performed using autopsy material in nine cases of CS, eight cases of PPS, and 20 controls without mental pathology. Groups were compared using covariance and correlation analyses.
Results
. The CS group, in contrast to PPS, showed a lower volume fraction (V
v
) of microglia in the subgroup aged over 50 years as compared with the control subgroup aged below than 50 years (60%,
p
< 0.05), along with greater V
v
and larger numbers of lipofuscin granules in the >50 subgroup than the >50 control subgroup (470%, 606%,
p
< 0.001). V
v
and number of mitochondria in microglia correlated negatively with heterochromatin area in microglia (
r
≥ –0.7,
p
< 0.05), while lipofuscin area correlated positively with heterochromatin area in microglia (
r
= 0.76,
p
< 0.05) and disease duration (
r
= 0.73,
p
< 0.05) only in the CS group. The number density of microglia in schizophrenia remained unaltered. Heterochromatin area was greater in both groups than in controls (
p
< 0.05) and correlated negatively with the number density of microglia in the CS group. The number of mitochondria in oligodendrocytes (reduced in CS) correlated positively with the number of mitochondria in microglia and negatively with the V
v
of lipofuscin granules in microglia and microglial nucleus area only in the CS group.
Conclusions
. The characteristics of CS, as compared with those of PPS, may be linked with disorders of mitochondrial and lipid metabolism in microglia, nuclear dysfunction, and accelerated aging of microglia, which can lead to impaired mitochondrial metabolism in oligodendrocytes.
We studied possible otoprotective effect of drugs widely used for the correction of perinatal hypoxic brain damage in premature infants. The experiments were carried out on immature rabbits with an ...immature hearing organ. The auditory function was assessed by DPOAE and ABR methods in intact animals and rabbits treated with therapeutic doses of netromycin alone or in combination with the drugs that normalize metabolic processes in the brain (Cortexin, Cogitum, Elkar, vitamin B2, ATP, and cocarboxylase). It was found that the administered drugs produced an otoprotective effect and reduced the severity, but did not eliminate the ototoxic effect.
Abstract
We demonstrate that in ferromagnets with the D
3h
point group of symmetry a possible origin of phase transition from a collinear ferromagnetic state to a non-collinear state can be the ...fourth order contributions to the free energy density that are allowed by this point group of symmetry. At the same time, Dzyaloshinskii-Moria interaction vanishes in such materials. Via symmetry analysis we derive seven possible fourth order contributions to the free energy density with respect to the unit vector of the local magnetization direction but only two of them can be considered as independent. Moreover, for two-dimensional systems only one survives. Considered symmetry class is essential because a large group of two-dimensional intrinsic ferromagnets belongs to it, for example a monolayer Fe
3
GeTe
2
. The four-spin chiral exchange does also manifest itself in peculiar magnon spectra and favors spin waves.
Monocyte activation is consistently reported in patients with schizophrenia (SZ). We aimed to study the ultrastructure of monocytes and monocyte production of IL-1β in drug-free patients with SZ and ...controls. Monocytes from young (18–30 y.o.) healthy and SZ men in relapse were studied. Electron microscopy and morphometry were applied to estimate areas of monocytes, volume density (Vv), areas, and number of organelles. The production IL-1β by monocytes was estimated by the ELISA method. Group differences were examined using ANCOVA. Pearson’s correlation coefficients were used to examine the effects of possible confounding variables. Correlation analyses were applied to detect the relationships between the parameters of monocytes measured and between the parameters measured and the IL-1β production. Area of nucleolus, Vv and area of mitochondria and lysosomes, and the number of lysosomes were significantly increased in patients as compared to controls. Area of mitochondria was correlated significantly with Vv and area of lysosomes, and the number of lysosomes was significantly correlated with area of monocyte and Vv of vacuoles only in the control group. The production of IL-1β by monocytes was higher in patients than in controls (
p
= 0.01) and was correlated with Vv of lysosomes (
r
= 0.68,
p
= 0.04) and area of lysosomes (
r
= 0.78,
p
= 0.013). The data provide new evidence for over activation of monocytes in SZ and disturbed metabolic relationships between lysosomes, mitochondria, and vacuoles.
A one-dimensional plasmon-polariton which is characterized by non-linear dispersion is supported by electromagnetic field interacting with topologically protected helical state. The electronic ...helical state arises at the surface of topological insulator in the close proximity of the ferromagnet. In a two-dimensional Dirac magnet these electro-optical excitations are limited by domain walls. Topological electronic imagining of domain walls can provide generally a novel tool to couple magnetic dynamics with both transport and optical properties of helical electronic states An exact dispersion relation for the topological plasmon-polariton were obtained.
(Gd
1
– x
Tb
x
)
2
O
3
(
x
= 0.04–0.22) films 115 to 150 nm in thickness have been grown on Si and SiO
2
substrates by metal organic chemical vapor deposition (MOCVD) using Ln(dpm)
3
precursors. ...After annealing in air at 800°C for removing carbon-containing impurities, the films were sulfided in NH
4
SCN vapor at temperatures from 700 to 1000°C in an Ar atmosphere until the formation of (Gd
1 –
x
Tb
x
)
2
O
2
S oxysulfides. The surface of the films is formed by grains 60 to 200 nm in size. The measured refractive index of the films is 2.2–2.4 and their estimated optical band gap (
E
g
) is 4.7–5.0 eV. The optical transmission of the films in the visible spectral region (400–750 nm) reaches 78–84%. The highest photoluminescence (PL) intensity in the oxysulfide films produced under identical conditions has been observed at
x
= 0.05. The blue component of their PL decreases with increasing terbium content and the emission shifts to the green spectral region.
Monoamine oxidase activity was quantitatively assessed by cytochemical method in brain structures (layers III and V of the sensorimotor cortex, caudate nucleus, nucleus accumbens, hippocampal CA3 ...field) of rats of August line and Wistar population with high and low locomotor activity in the open fi eld test. Monoamine oxidase activity (substrate tryptamine) predominated in the nucleus accumbens of Wistar rats with high motor activity in comparison with rats with low locomotor activity. In August rats, enzyme activity (substrates tryptamine and serotonin) predominated in the hippocampus of animals with high motor activity. Comparison of August rats with low locomotor activity and Wistar rats with high motor activity (i.e. animals demonstrating maximum differences in motor function) revealed significantly higher activity of the enzyme (substrates tryptamine and serotonin) in the hippocampus of Wistar rats. The study demonstrates clear-cut morphochemical specificity of monoaminergic metabolism based on the differences in the cytochemical parameter “monoamine oxidase activity”, in the studied brain structures, responsible for the formation and realization of goal-directed behavior in Wistar and August rats.
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