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Choroid plexus, pineal gland, and habenula tend to accumulate physiologic calcifications (concrements) over a lifetime. However, until now the composition and causes of the intracranial calcifications remain unclear. The detailed analysis of concrements has been done by us using X-ray diffraction analysis (XRD), X-ray diffraction topography (XRDT), micro-CT, X-ray phase-contrast tomography (XPCT), as well as histology and immunohistochemistry (IHC). By combining physical (XRD) and biochemical (IHC) methods, we identified inorganic (hydroxyapatite) and organic (vimentin) components of the concrements. Via XPCT, XRDT, histological, and IHC methods, we assessed the structure of concrements within their appropriate tissue environment in both two and three dimensions. The study found that hydroxyapatite was a major component of all calcified depositions. It should be noted, however, that the concrements displayed distinctive characteristics corresponding to each specific structure of the brain. As a result, our study provides a basis for assessing the pathological and physiological changes that occur in brain structure containing calcifications. [ABSTRACT FROM AUTHOR]

Postmortem changes occurring in human carotid body were simulated on the Wistar rat model. It was shown that light, dark, and pyknotic (progenitor) subtypes of human carotid body cells are an artifact and cannot be used in clinical practice to study the characteristics of various human diseases. The differences between the control group of healthy individuals and individuals with the various pathologies are most likely due to the different levels of premortal hypoxia that the tissue had been exposed to. Moreover, widespread antigens used in practice were divided into 2 groups by their tolerance to autolysis: stable and unstable ones. This can be useful for the development of immunohistochemical test algorithms for the diagnostics on autopsy material. [ABSTRACT FROM AUTHOR]

Toxins produced by Clostridioides difficile inactivate small GTPases leading to reorganization of cellular processes, cell death, and in the worst case death of patients. We explore the molecular effects of these toxins on target cells using LC-MS-based proteome and phosphoproteome techniques. Sample preparation with extensive fractionation is highly important for LC-MS-based studies to increase depths of proteome coverage and affinity chromatography is crucial to detect as many phosphopeptides as possible. [ABSTRACT FROM AUTHOR]

Neurophysiological monitoring is of undoubted value for the intraoperative safety of neurosurgical procedures. Widely developed and used for cranial surgery, it is equally as effective, though perhaps less commonly employed, for spinal pathology. The most frequently used techniques for intraoperative monitoring during spinal surgery include somatosensory evoked potentials (SSEPs), motor evoked potentials (MEPs) and electromyography, which can either be spontaneous free-running (sEMG) or triggered (tEMG). The knowledge of the benefits and limitations of each modality is essential in optimising the value of intraoperative monitoring during spinal procedures. This review will analyse the single techniques, their anatomical and physiological basis, their use in spinal surgery as reliable indicators of functional injury, their limits and their application to specific procedures in minimally invasive surgery, such as the lateral transpsoas access for interbody fusion and the divergent trajectory for cortico-pedicular screws. In these particular techniques, because of reduced visual exposure, neuromonitoring is indeed essential to exploit the full potential of minimally invasive surgery, while avoiding damage to nervous structures. [ABSTRACT FROM AUTHOR]

Retinal degeneration leads to release of cell-type specific proteins into the adjacent compartment. Here we investigated whether the neurofilament heavy chain protein (NfH) could be measured from the vitreous body and anterior chamber fluid. This prospective study included 85 patients who underwent vitrectomy (44 retinal detachment, 12 macular hole, 15 epiretinal gliosis, 8 organ donors) or trabelectomy (six glaucoma). The cut-off level was calculated from the organ donors. An established enzyme-linked immunosorbent assay (ELISA, SMI35) was used for quantification of NfH (190–210 kDa). Measurable levels of NfH were detected from the vitreous body homogenate, but not from the anterior chamber fluid. The cut-off level was 0.29 ng/mL. A significant proportion of patients suffering from retinal detachment (43.2%, mean 0.74 ng/mL) had vitreous body NfH levels above cut-off when compared to organ donors (0%, 0.12 ng/mL, p = 0.02), epiretinal sclerosis (1.6%, 0.05 ng/mL, p = 0.01), macular hole (0%, 0.04 ng/mL, p = 0.004). Following retinal detachment, vitreous NfH-SMI35 levels correlated with time from onset ( R = −0.3, p < 0.05), persisting for up to 2 years. This study shows that NfH can be quantified from the human vitreous body and may be a useful novel biomarker for retinal degeneration. The method can be applied for investigating the dynamics of retinal degeneration and the response to neuroprotective strategies in a broad range of retinal diseases in either clinical or experimental research. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to investigate the effect of glutamate agonists upon kynurenic acid (KYNA) production in bovine retinal slices. Quantitative analysis of newly synthesized KYNA was carried out using an HPLC system and detected fluorimetrically. Glutamate at the concentration of 0.01, 0.1 and 1 mM reduced KYNA synthesis in the retinal slices to 70% (p < 0.05), 35% (p < 0.01) and 23% (p < 0.001), respectively. The concentration of glutamate reducing production of KYNA by 50% (IC50) was 0.035 mM (0.02–0.06). Aspartate at the concentration of 0.01, 0.1 and 1 mM lowered KYNA synthesis in the retinal slices to 80% (p < 0.01), 57% (p < 0.001) and 43% (p < 0.001), respectively. In contrast, kainic acid (up to 5 mM), α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) (up to 1 mM) and 1-aminocyclopentane-trans-1,3-dicarboxylic acid (t-ACPD) (up to 3 mM) turned out to be ineffective in diminishing KYNA synthesis. These data demonstrate that glutamate, aspartate and N-methyl-D-aspartate (NMDA) inhibit KYNA synthesis in bovine retinal slices with different potency. [ABSTRACT FROM AUTHOR]

In accordance with the data reporting the identification of nitric oxide synthase (NOS) and vasoactive intestinal polypeptide (VIP) positive nerve fibres in the trabecular meshwork of the corpus cavernosum, we suggest that nitric oxide (NO) and VIP may serve complementary physiological roles in penile erection. Therefore SIN-1 and VIP were administered alone and in combination in an in vivo rabbit model. All rabbits revealed basal pressure values of 5-8 cm H[sub 2]O intracavernously. In the rabbits intracavernously (i.c.) injected with SIN-1 alone and VIP alone, no adequate erectile responses were observed. Whereas, in the group intracavernously injected with the combination of SIN-1 + VIP, erectile responses with mean maximal intracavernous pressure (max. ICP) 52.8 (±13.2) cm H[sub 2]O were noted. These pressure elevations do not statistically diverge (P>0.05) than the ones obtained in the control group administered i.c. injections of the combination of papaverine/phentolamine (mean max. ICP 51 ( ± 14.73) cm H[sub 2]O). Referring to our results, we conclude that the combined use of SIN-1 + VIP could play an important role in the physiological treatment of erectile dysfunction. [ABSTRACT FROM AUTHOR]