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Background: The origin of chronic subdural hematomas (CSDH) and the pathophysiology of its enlargement remain unknown. The chemical fluid composition of CSDH, the contribution of cerebrospinal fluid (CSF) to its enlargement, and the relationship to its appearance on computed tomography (CT) also are not entirely clear., Methods: In this prospective study, 58 samples in 41 patients treated surgically for CSDH were analyzed. CSDHs were evaluated for the presence of CSF via β-2 transferrin and substances related to cell breakdown and hemolysis. These were compared with normal value of those substances in the serum and the CT appearances of the CSDH., Results: In this study, 24% of the samples contained β-2 transferrin, which was statistically significant. Total protein, lactate dehydrogenase, total bilirubin, and red blood cells also were statistically different when compared with their normal serum concentration, indicating an active process of rebleeding and hemolysis rather than plasma ultrafiltration; however, their concentrations did not correlate with specific CT scan appearance. The absence of CSF in CSDH in 76% of cases did not support the theory that most CSDHs originate from subdural hygromas. The presence of hemolysis and cell breakdown, byproducts supports the hypothesis that the primary enlargement of CSDH develops through neomembrane and neovascular formation, rebleeding, and inhibition of the blood coagulation process. Our study did not test for serum transudation as a component of the enlargement of CSDH., Conclusions: Our study confirms that the origin and enlargement of CSDH is multifactorial, but the contribution of individual factors and condition under which it occurs still remains unclear. CT scan findings do not correlate with the chemical composition or the presence of CSF in the CSDH., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The interfacial coupling of two materials with different ordered phases, such as a superconductor (S) and a ferromagnet (F), is driving new fundamental physics and innovative applications. For example, the creation of spin-filter Josephson junctions and the demonstration of triplet supercurrents have suggested the potential of a dissipationless version of spintronics based on unconventional superconductivity. Here we demonstrate evidence for active quantum applications of S-F-S junctions, through the observation of macroscopic quantum tunnelling in Josephson junctions with GdN ferromagnetic insulator barriers. We show a clear transition from thermal to quantum regime at a crossover temperature of about 100 mK at zero magnetic field in junctions, which present clear signatures of unconventional superconductivity. Following previous demonstration of passive S-F-S phase shifters in a phase qubit, our result paves the way to the active use of spin filter Josephson systems in quantum hybrid circuits.

Galanin released into the hypophysial portal circulation in the hypothalamus may function as a hypophysiotropic factor regulating the anterior pituitary function or it may function as a neurotransmitter/neuromodulator acting at synaptic sites regulating neuronal activity of many neurons in the brain. Catecholamines (adrenaline, noradrenaline, and dopamine) primarily regulate anterior pituitary functions indirectly via innervating hypophysiotropic neurons. The aim of the present studies was to explore with double-label immunocytochemistry if, as in rodents, catecholamines interact with galanin in the human diencephalon. Due to the long post-mortem period and subsequent lack of optimal preservation of the cell membranes in the brain, electron microscopy could not be employed to show the presence of catecholaminergic-immunoreactive synapses on galanin-immunoreactive neurons. Therefore, we used light microscopic immunocytochemistry and high-magnification microscopy with oil immersion to identify putative juxtapositions between catecholamines and galanin-utilizing antisera against key enzymes of catecholamine synthesis (tyrosine hydroxylase (TH), representing all three catecholamines; dopamine-beta-hydroxylase (DBH), representing noradrenaline; and phenylethanolamine-N-methyltransferase (PNMT), representing adrenaline) and galanin. Our studies show that among the three catecholamines, dopamine is the most abundant and the vast majority of catecholaminergic contacts on galanin-immunoreactive neurons is dopaminergic. The number of DBH-immunoreactive contacts is less and the number of PNMT-immunopositive contacts is negligible. Among the hypothalamic regions, the periventricular region above the infundibulum (infundibular or arcuate nucleus) contained the largest number of contacts. These en passant-type intimate associations between catecholamine- and galanin-immunoreactive neuronal elements may be functional synapses and may provide the morphological basis for the catecholamine-mediated galanin release., (Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.)

Dissipation encodes the interaction of a quantum system with the environment and regulates the activation regimes of a Brownian particle. We have engineered grain boundary biepitaxial YBaCuO junctions to drive a direct transition from a quantum activated running state to a phase diffusion regime. The crossover to the quantum regime is tuned by the magnetic field and dissipation is described by a fully consistent set of junction parameters. To unravel phase dynamics in moderately damped systems is of general interest for advances in the comprehension of retrapping phenomena and in view of quantum hybrid technology.

Context: Stress is considered to be a major factor in the regulation of growth. Psychosocial dwarfism, characterized with short stature, delayed puberty, and depression, is typically preceded by psychological harassment or stressful environment. It has been observed that stress suppresses GH secretion, possibly via the attenuation of GHRH secretion. However, the exact mechanism of the impact of stress on growth has not been elucidated yet., Objective: Our previous studies revealed intimate associations between neuropeptide Y (NPY)-immunoreactive (IR) axonal varicosities and GHRH-IR perikarya in the human hypothalamus. Because NPY is considered to be a stress molecule, NPY-GHRH juxtapositions may represent an important factor of stress-suppressed GHRH release. In addition to NPY, catecholamines are among the major markers of stress. Thus, in the present study, we examined the putative juxtapositions between the catecholaminergic tyrosine hydroxylase (TH)-/dopamine-β-hydroxylase-/phenylethanolamine N-methyltransferase-IR and GHRH-IR neural elements in the human hypothalamus. To reveal these juxtapositions, double-label immunohistochemistry was used., Results: Our findings revealed that the majority of the GHRH-IR perikarya formed intimate associations with TH-IR fiber varicosities. The majority of these juxtapositions were found in the infundibular nucleus/median eminence., Conclusions: The lack of phenylethanolamine N-methyltransferase-GHRH associations and the small number of dopamine-β-hydroxylase-GHRH juxtapositions suggest that the vast majority of the observed TH-GHRH juxtapositions represent dopaminergic associations. The density of the abutting TH-IR fibers on the surface of the GHRH perikarya suggests that these juxtapositions may be functional synapses, and thus, in addition to NPY, catecholamines may regulate GHRH secretion via direct synaptic mechanisms.

Neuropeptide Y (NPY) is a 36 amino acid peptide, which among others, plays a pivotal role in stress response. Although previous studies confirmed that NPY release is increased by stress in several species, the exact mechanism of the stress-induced NPY release has not been elucidated yet. In the present study, we examined, with morphological means, the possibility that catecholamines directly influence NPY release in the human hypothalamus. Since the use of electron microscopic techniques is virtually impossible in immunostained human samples due to the long post mortem time, double-label immunohistochemistry was utilised in order to reveal the putative catecholaminergic-NPY associations. The present study is the first to demonstrate juxtapositions between the catecholaminergic, tyrosine hydroxylase (TH)/dopamine-beta hydroxylase (DBH)-immunoreactive (IR) and NPY-IR neural elements in the human hypothalamus. These en passant type associations are most numerous in the infundibular and periventricular areas of the human diencephalon. Here, NPY-IR neurons often form several contacts with catecholaminergic fibre varicosities, without any observable gaps between the contacting elements, suggesting that these juxtapositions may represent functional synapses. The lack of phenylethanolamine N-methyltransferase (PNMT)-NPY juxtapositions and the relatively few observed DBH-NPY associations suggest that the vast majority of the observed TH-NPY juxtapositions represent dopaminergic synapses. Since catecholamines are known to be the crucial components of the stress response, the presence of direct, catecholaminergic (primarily dopaminergic)-NPY-IR synapses may explain the increased NPY release during stress. The released NPY in turn is believed to play an active role in the responses that are directed to maintain the homeostasis during stressful conditions., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Previous studies have demonstrated that catecholaminergic, tyrosine hydroxylase (TH)-immunoreactive (IR) perikarya and fibers are widely distributed in the human hypothalamus. Since TH is the key and rate-limiting enzyme for catecholaminergic synthesis, these IR neurons may represent dopaminergic, noradrenergic or adrenergic neural elements. However, the distribution and morphology of these neurotransmitter systems in the human hypothalamus is not entirely known. Since the different catecholaminergic systems can be detected by identifying the neurons containing the specific key enzymes of catecholaminergic synthesis, in the present study we mapped the catecholaminergic elements in the human hypothalamus using immunohistochemistry against the catecholaminergic enzymes, TH, dopamine beta-hydroxylase (DBH) and phenylethanolamine-N-methyltransferase (PNMT). Only a few, PNMT-IR, adrenergic neuronal elements were found mainly in the infundibulum and the periventricular zone. DBH-IR structures were more widely distributed in the human hypothalamus occupying chiefly the infundibulum/infundibular nucleus, periventricular area, supraoptic and paraventricular nuclei. Dopaminergic elements were detected by utilizing double label immunohistochemistry. First, the DBH-IR elements were visualized; then the TH-IR structures, that lack DBH, were detected with a different chromogen. In our study, we conclude that all of the catecholaminergic perikarya and the majority of the catecholaminergic fibers represent dopaminergic neurons in the human hypothalamus. Due to the extremely small number of PNMT-IR, adrenergic structures in the human hypothalamus, the DBH-IR fibers represent almost exclusively noradrenergic neuronal processes. These findings suggest that the juxtapositions between the TH-IR and numerous peptidergic systems revealed by previous reports indicate mostly dopaminergic synapses., (Copyright © 2010 IBRO. Published by Elsevier Ltd. All rights reserved.)

Galanin and neuropeptide Y (NPY) are among the most abundant neuropeptides in the hypothalamus. The role of NPY and galanin in the regulation of the secretory activity of the anterior pituitary has been well established. In addition, the two peptides interact with a number of neurons synthesizing the releasing and inhibiting hormones and a large number of other neuropeptides. The aim of the present studies was to explore if, as in rodents, NPY innervates galanin-immunoreactive (IR) neurons in the human diencephalon. Due to the long post mortem period and subsequent lack of optimal preservation of the cell membranes in the brain, electron microscopy could not be employed to show the presence of NPY-IR synapses on galanin-IR neurons. Therefore, we used light microscopic double label immunocytochemistry and high magnification microscopy with oil immersion to identify putative juxtapositions between NPY and galanin. Our studies show that similarly to rats, numerous NPY-IR nerve terminals surrounded galanin-IR neurons in the human hypothalamus. Among the hypothalamic regions, the infundibulum (infundibular or arcuate nucleus) contained the largest number of galanin-IR neurons heavily surrounded with NPY-IR nerve terminals. These en passant-type intimate associations between NPY-IR and galanin-IR neuronal elements may be functional synapses and may provide the morphological basis for the NPY-mediated galanin release. Consequently, NPY-galanin communication may mediate effects of NPY on neuronal systems innervated by galanin, and therefore may play a pivotal role in the regulation of reproduction, growth, energy and metabolism., (Copyright © 2010 IBRO. Published by Elsevier Ltd. All rights reserved.)

We have investigated the static and dynamic properties of long YBa2Cu3O(7-delta) 0-pi Josephson junctions and compared them with those of conventional 0 junctions. Scanning SQUID microscope imaging has revealed the presence of a semifluxon at the phase discontinuity point in 0-pi Josephson junctions. Zero field steps have been detected in the current-voltage characteristics of all junctions. Comparison with simulation allows us to attribute these steps to fluxons traveling in the junction for conventional 0 junctions and to fluxon-semifluxon interactions in the case of 0-pi Josephson junctions.

Here we present the direct observation of macroscopic quantum properties in an all high-critical-temperature superconductor d-wave Josephson junction. Although dissipation caused by low-energy excitations is expected to strongly suppress macroscopic quantum effects, we demonstrate energy level quantization in our d-wave Josephson junction. The result indicates that the role of dissipation mechanisms in high-temperature superconductors has to be revised, and it may also have consequences for the class of solid-state "quiet" quantum bits with superior coherence time.

The escape rate from the zero voltage state in a superconducting Josephson junction (JJ) is determined by the temperature, but it saturates at low temperature due to macroscopic quantum tunneling (MQT). Complications due to d-wave symmetry in a high temperature superconductor, like low energy quasiparticles and an unconventional current-phase relation, may influence the escape rate. We report, for the first time to our knowledge, the observation of MQT in a YBa(2)Cu(3)O(7-delta) grain boundary biepitaxial JJ. This proves that dissipation can be significantly reduced by a proper junction configuration, which is of significance for quantum coherence.

A novel dynamical state has been observed in the dynamics of a perturbed sine-Gordon system. This resonant state has been experimentally observed as a singularity in the dc current-voltage characteristic of an annular Josephson tunnel junction, excited in the presence of a magnetic field. In this respect it can be assimilated to self-resonances known as Fiske steps. Differently from these, however, we demonstrate, on the basis of numerical simulations, that its detailed dynamics involves rotating fluxon pairs, a mechanism associated, so far, to self-resonances known as zero-field steps. This occurs because the size of nonlinear excitations is comparable with that of the system.

Many experiments on high-temperature superconductors have shown paramagnetic behavior when the sample is field cooled. The paramagnetism was attributed to a d-wave order parameter creating pi-junctions in the samples. However, the same effect was later discovered in traditional low-temperature superconductors and conventional Josephson-junction arrays which are s wave. By simulating both conventional and mixed pi/conventional Josephson-junction arrays we determine that differences exist which may be sufficient to clearly identify the presence of pi junctions. In particular, the pi junctions cause a symmetry breaking providing a measurable signature of their presence.