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A munkáltató munkajogi kártérítési felelősséggel tartozik a munkavállalóinak okozott károkért. A Munka Törvénykönyve 2012-ben bekövetkezett módosítása érintette a kártérítési felelősség szabályait is, főleg a munkáltató mentesülési lehetőségei körében. A tanulmány annak vizsgálatára irányul, hogy ez a módosítás eredményezett-e könnyebbséget a munkáltató oldalán, illetve milyen jelentősége van a munkáltató és a bíróság gyakorlatában a munkavédelemnek. A dolgozat első felében a munkáltató gazdasági érdekeit vizsgálom abból a szempontból, hogy a változó bírósági gyakorlat alapján megéri-e a balesetek megelőzésébe pénzt fektetni. Ezt követően a kutatás alapjául szolgáló jogeseteket igyekszem csoportokra bontani, és mindegyik feltárt nehézséget egy-egy munkabalesettel szemléltetni. Az öt csoport:1) a munkavédelmi szabályok megsértésével okozott balesetek alóli mentesülés nehézségei, 2) harmadik személyek okozta munkabalesetek estén felmerülő kártérítési és munkavédelmi nehézségek, 3) a munkáltató ellenőrzési kötelezettségének megsértése esetén bekövetkezett munkabalesetek, 4) a szélsőséges időjárási viszonyok során bekövetkezett balesetek, illetve 5) egyéb kategóriába sorolt munkabalesetek problémái.

A klinikai gyakorlatban elterjedt sztatinterápia mellékhatásai során leggyakrabban izompanaszokkal találkozunk. Ennek legsúlyosabb formája a rhabdomyolysis, amely potenciálisan életveszélyes következményekkel járhat. Az állapot kezelése mellett az etiológia tisztázása minden esetben szükséges. Egyes hajlamosító állapotok mellett a sztatinok metabolizációjának sérülése lehet a kulcsmozzanat. Esetünkben nem gyógyszer-interakció, hanem a sztatin májon keresztüli kiürülésének gátlása vezetett rhabdomyolysis kialakulásához és derített fényt egy addig tünetmentes betegségre.

Összefoglaló. A Bouveret-szindróma egy bilioenteralis fistulán keresztül a vékonybélbe – az esetek 85%-ában a duodenumba – jutó nagy epekő okozta bélelzáródást jelenti. Leggyakrabban idős nők körében fordul elő. Jelen közleményünk célja e kórkép tüneteinek, diagnosztikájának és terápiás lehetőségeinek ismertetése egy esetbemutatás kapcsán. A 79 éves nőbeteg felvételi hasi panaszainak hátterében típusos gyomorkimenet-obstrukciós szindrómát okozó, a duodenumban beékelődött epekő, Bouveret-szindróma igazolódott. A diagnózist az elvégzett natív hasi röntgen és hasi ultrahangvizsgálatok már felvetették, de megerősítésére további képalkotó vizsgálatot (hasi CT) és endoszkópos beavatkozást végeztünk. Ezt követően sebészeti beavatkozás történt, melynek során a cholecystoduodenalis fistula zárása és az epekő eltávolítása után a beteg gyógyultan távozott. Közleményünkben a diagnózisfelállítás idejének fontosságáról, illetve a terápiás lehetőségekről számolunk be, valamint szeretnénk felhívni a figyelmet az epekő okozta gyomorürülési zavar ezen ritka formájára. Orv Hetil. 2021; 162(49): 1982–1986. Summary. Bouveret syndrome is a rare form of bowel obstruction resulting to the small intestine – in 85% of the cases to the duodenum – caused by a gallstone from a bilioenteral fistula. It occurs most commonly in elderly women. The aim of the present study is to describe the symptoms, diagnostic and therapeutic options of Bouveret syndrome due to our case report. The background of epigastric pain of the 79-year-old woman was the typical gastric outlet obstruction syndrome caused by Bouveret syndrome with an impacted gallstone into the duodenum. This diagnosis was suggested by abdominal X-ray and abdominal ultrasound; however, it was confirmed with abdominal computer tomography and upper gastrointestinal endoscopy. This was followed by surgical intervention to close the cholecystoduodenal fistula and remove the gallstone, finally the cured patient was discharged. In our study, we summarize the importance of timely diagnosis and therapeutic options, respectively, furthermore, draw attention to this rare form of gallstone-caused gastric outlet obstruction syndrome. Orv Hetil. 2021; 162(49): 1982–1986.

Inhibitory neurons innervating the perisomatic region of cortical excitatory principal cells are known to control the emergence of several physiological and pathological synchronous events, including epileptic interictal spikes. In humans, little is known about their role in synchrony generation, although their changes in epilepsy have been thoroughly investigated. This paper demonstraits how parvalbumin (PV)- and type 1 cannabinoid receptor (CB1R)-positive perisomatic interneurons innervate pyramidal cell bodies, and their role in synchronous population events spontaneously emerging in the human epileptic and non-epileptic neocortex, in vitro. Quantitative electron microscopy showed that the overall, PV+ and CB1R+ somatic inhibitory inputs remained unchanged in focal cortical epilepsy. On the contrary, the size of PV-stained synapses increased, and their number decreased in epileptic samples, in synchrony generating regions. Pharmacology demonstrated—in conjunction with the electron microscopy—that although both perisomatic cell types participate, PV+ cells have stronger influence on the generation of population activity in epileptic samples. The somatic inhibitory input of neocortical pyramidal cells remained almost intact in epilepsy, but the larger and consequently more efficient somatic synapses might account for a higher synchrony in this neuron population. This, together with epileptic hyperexcitability, might make a cortical region predisposed to generate or participate in hypersynchronous events.

4-aminopyridine (4-AP) is a widely used drug that induces seizure activity in rodents, especially in rats, although there is no consensus in the literature on the dose to be used in mice. The aim of the present study was to investigate the effect of the intraperitoneal administration of 4-AP in two doses (4 and 10 mg/kg) in vivo. EEG, movement, and video recordings were made simultaneously in male B6 mice to specify the details of the seizures and to determine whether there is a suitable non-lethal dose for seizure induction and for further molecular studies. Seizure behavior in mice differs from that seen in rats, with no characteristic stages of epileptic seizures, but with spiking and seizure activity. Seizure activity, although produced at both doses without being lethal, induced different changes of the EEG pattern. Smaller dose induced a lower amplitude seizure activity, decreased spiking activity and later onset of seizures, while higher dose induced a much more intense brain seizure activity and severe trembling. It is concluded that the intraperitoneal administration of 4-AP at a dose of 10 mg/kg induces explicit seizure activity in mice which is repeatable and can be suitable for further molecular research.

Intrinsically disordered proteins (IDPs) play important roles in disease pathologies; however, their lack of defined stable 3D structures make traditional drug design strategies typically less effective against these targets. Based on promising results of targeted covalent inhibitors (TCIs) on challenging targets, we have developed a covalent design strategy targeting IDPs. As a model system we chose tau, an endogenous IDP of the central nervous system that is associated with severe neurodegenerative diseases via its aggregation. First, we mapped the tractability of available cysteines in tau and prioritized suitable warheads. Next, we introduced the selected vinylsulfone warhead to the non-covalent scaffolds of potential tau aggregation inhibitors. The designed covalent tau binders were synthesized and tested in aggregation models, and inhibited tau aggregation effectively. Our results revealed the usefulness of the covalent design strategy against therapeutically relevant IDP targets and provided promising candidates for the treatment of tauopathies.

Knowledge about the activity of single neurons is essential in understanding the mechanisms of synchrony generation, and particularly interesting if related to pathological conditions. The generation of interictal spikes—the hypersynchronous events between seizures—is linked to hyperexcitability and to bursting behaviour of neurons in animal models. To explore its cellular mechanisms in humans we investigated the activity of clustered single neurons in a human in vitro model generating both physiological and epileptiform synchronous events. We show that non-epileptic synchronous events resulted from the finely balanced firing of excitatory and inhibitory cells, which was shifted towards an enhanced excitability in epileptic tissue. In contrast, interictal-like spikes were characterised by an asymmetric overall neuronal discharge initiated by excitatory neurons with the presumptive leading role of bursting pyramidal cells, and possibly terminated by inhibitory interneurons. We found that the overall burstiness of human neocortical neurons is not necessarily related to epilepsy, but the bursting behaviour of excitatory cells comprising both intrinsic and synaptically driven bursting is clearly linked to the generation of epileptiform synchrony.

Background This study was carried out to determine the prevalence and the genetic background of extended-spectrum β-lactamase-producing Escherichia coli invasive isolates obtained from a tertiary-care hospital in Budapest, Hungary. Methods Between October–November 2018, all invasive ESBL-producing E. coli isolates were collected from Central Hospital of Southern Pest. The antimicrobial susceptibility testing was performed according to the EUCAST guidelines. The possible clonal relationships were investigated by core genome (cg)MLST (SeqSphere +) using whole-genome sequencing (WGS) data of isolates obtained from Illumina 251-bp paired-end sequencing. From WGS data acquired antimicrobial resistance genes, virulence genes and replicon types were retrieved using ResFinder3.1, PlasmidFinder2.1, pMLST-2.0, VirulenceFinder2.0 and Virulence Factors Database online tools. Results Overall, six E. coli isolates proved to be resistant to third-generation cephalosporins and ESBL-producers in the study period. Full genome sequence analysis showed that five E. coli isolates belonged to the ST131 clone: two to C1-M27 subclade with blaCTX-M-27 and three to C2/H30Rx subclade with blaCTX-M-15. One isolate belonged to ST1193 with blaCTX-M-27. According to cgMLST, all C2/H30Rx isolates formed a cluster (≤ 6 allele differences), while the blaCTX-M-27-producing C1-M27 isolates differed at least 35 alleles from each other. Both C2/H30Rx and C1-M27 ST131 isolates harbored similar antimicrobial resistance gene sets. However, only C2/H30Rx isolates had the qnrB and aac(3)-IIa. The isolates carried similar extraintestinal virulence gene set but differed in some genes encoding siderophores, protectins and toxins. Moreover, only one C2/H30Rx isolate carried salmochelin siderophore system and showed virotype B. All isolates showed resistance against ceftriaxone, cefotaxime, and ciprofloxacin, and the C2/H30Rx isolates were also resistant to gentamicin, tobramycin, and ceftazidime. Conclusions Out of six ESBL-producing E. coli, five belonged to the ST131 clone. This study indicates, that the C2/H30Rx and C1-M27 subclades of the ST131 appear to be the dominant clones collected in a Hungarian hospital.

Stereo-electroencephalography depth electrodes, regularly implanted into drug-resistant patients with focal epilepsy to localize the epileptic focus, have a low channel count (6–12 macro- or microelectrodes), limited spatial resolution (0.5–1 cm) and large contact area of the recording sites (~mm2). Thus, they are not suited for high-density local field potential and multiunit recordings. In this paper, we evaluated the long-term electrophysiological recording performance and histocompatibility of a neural interface consisting of 32 microelectrodes providing a physical shape similar to clinical devices. The cylindrically-shaped depth probes made of polyimide (PI) were chronically implanted for 13 weeks into the brain of rats, while cortical or thalamic activity (local field potentials, single-unit and multi-unit activity) was recorded regularly to monitor the temporal change of several features of the electrophysiological performance. To examine the tissue reaction around the probe, neuron-selective and astroglia-selective immunostaining methods were applied. Stable single-unit and multi-unit activity were recorded for several weeks with the implanted depth probes and a weak or moderate tissue reaction was found around the probe track. Our data on biocompatibility presented here and in vivo experiments in non-human primates provide a strong indication that this type of neural probe can be applied in stereo-electroencephalography recordings of up to 2 weeks in humans targeting the localization of epileptic foci providing an increased spatial resolution and the ability to monitor local field potentials and neuronal spiking activity.

KEY POINTS Hyperexcitability and hypersynchrony of neuronal networks are thought to be linked to the generation of epileptic activity in both humans and animal models. Here we show that human epileptic postoperative neocortical tissue is able to generate two different types of synchronies in vitro. Epileptiform bursts occurred only in slices derived from epileptic patients and were hypersynchronous events characterized by high levels of excitability. Spontaneous population activity emerged in both epileptic and non-epileptic tissue, with a significantly lower degree of excitability and synchrony, and could not be linked to epilepsy. These results help us to understand better the role of excitatory and inhibitory neuronal circuits in the generation of population events, and to define the subtle border between physiological and pathological synchronies. ABSTRACT Interictal activity is a hallmark of epilepsy diagnostics and is linked to neuronal hypersynchrony. Little is known about perturbations in human epileptic neocortical microcircuits, and their role in generating pathological synchronies. To explore hyperexcitability of the human epileptic network, and its contribution to convulsive activity, we investigated an in vitro model of synchronous burst activity spontaneously occurring in postoperative tissue slices derived from patients with or without preoperative clinical and electrographic manifestations of epileptic activity. Human neocortical slices generated two types of synchronies. Interictal-like discharges (classified as epileptiform events) emerged only in epileptic samples, and were hypersynchronous bursts characterized by considerably elevated levels of excitation. Synchronous population activity was initiated in both epileptic and non-epileptic tissue, with a significantly lower degree of excitability and synchrony, and could not be linked to epilepsy. However, in pharmacoresistant epileptic tissue, a higher percentage of slices exhibited population activity, with higher local field potential gradient amplitudes. More intracellularly recorded neurons received depolarizing synaptic potentials, discharging more reliably during the events. Light and electron microscopic examinations showed slightly lower neuron densities and higher densities of excitatory synapses in the human epileptic neocortex. Our data suggest that human neocortical microcircuits retain their functionality and plasticity in vitro, and can generate two significantly different synchronies. We propose that population bursts might not be pathological events while interictal-like discharges may reflect the epileptogenicity of the human cortex. Our results show that hyperexcitability characterizes the human epileptic neocortical network, and that it is closely related to the emergence of synchronies.

Aberrant methylation is one of the most frequent epigenetic alterations that can contribute to tumor formation. Cell-free DNA can originate from tumor tissue; therefore, the evaluation of methylation markers in cell-free DNA can be a promising method for cancer screening. Our aim was to develop a panel of biomarkers with altered methylation along the colorectal adenoma-carcinoma sequence in both colonic tissue and plasma. Methylation of selected CpG sites in healthy colonic (n = 15), adenoma (n = 15), and colorectal cancer (n = 15) tissues was analyzed by pyrosequencing. MethyLight PCR was applied to study the DNA methylation of SFRP1, SFRP2, SDC2, and PRIMA1 gene promoters in 121 plasma and 32 biopsy samples. The effect of altered promoter methylation on protein expression was examined by immunohistochemistry. Significantly higher (P < 0.05) DNA methylation levels were detected in the promoter regions of all 4 markers, both in CRC and adenoma tissues compared with healthy controls. Methylation of SFRP1, SFRP2, SDC2, and PRIMA1 promoter sequences was observed in 85.1%, 72.3%, 89.4%, and 80.9% of plasma samples from patients with CRC and 89.2%, 83.8%, 81.1% and 70.3% from adenoma patients, respectively. When applied as a panel, CRC patients could be distinguished from controls with 91.5% sensitivity and 97.3% specificity [area under the curve (AUC) = 0.978], while adenoma samples could be differentiated with 89.2% sensitivity and 86.5% specificity (AUC = 0.937). Immunohistochemical analysis indicated decreasing protein levels of all 4 markers along the colorectal adenoma-carcinoma sequence. Our findings suggest that this methylation biomarker panel allows non-invasive detection of colorectal adenoma and cancer from plasma samples.

The use of SU-8 material in the production of neural sensors has grown recently. Despite its widespread application, a detailed systematic quantitative analysis concerning its biocompatibility in the central nervous system is lacking. In this immunohistochemical study, we quantified the neuronal preservation and the severity of astrogliosis around SU-8 devices implanted in the neocortex of rats, after a 2 months survival. We found that the density of neurons significantly decreased up to a distance of 20 μm from the implant, with an averaged density decrease to 24 ± 28% of the control. At 20 to 40 μm distance from the implant, the majority of the neurons was preserved (74 ± 39% of the control) and starting from 40 μm distance from the implant, the neuron density was control-like. The density of synaptic contacts – examined at the electron microscopic level – decreased in the close vicinity of the implant, but it recovered to the control level as close as 24 μm from the implant track. The intensity of the astroglial staining significantly increased compared to the control region, up to 560 μm and 480 μm distance from the track in the superficial and deep layers of the neocortex, respectively. Electron microscopic examination revealed that the thickness of the glial scar was around 5–10 μm thin, and the ratio of glial processes in the neuropil was not more than 16% up to a distance of 12 μm from the implant. Our data suggest that neuronal survival is affected only in a very small area around the implant. The glial scar surrounding the implant is thin, and the presence of glial elements is low in the neuropil, although the signs of astrogliosis could be observed up to about 500 μm from the track. Subsequently, the biocompatibility of the SU-8 material is high. Due to its low cost fabrication and more flexible nature, SU-8 based devices may offer a promising approach to experimental and clinical applications in the future.

Key points •Initiation of pathological synchronous events such as epileptic spikes and seizures is linked to the hyperexcitability of the neuronal network in both humans and animals. •In the present study, we show that epileptiform interictal-like spikes and seizures emerged in human neocortical slices by blocking GABAA receptors, following the disappearance of the spontaneously occurring synchronous population activity. •Large variability of temporally and spatially simple and complex spikes was generated by tissue from epileptic patients, whereas only simple events appeared in samples from non-epileptic patients. •Physiological population activity was associated with a moderate level of principal cell and interneuron firing, with a slight dominance of excitatory neuronal activity, whereas epileptiform events were mainly initiated by the synchronous and intense discharge of inhibitory cells. •These results help us to understand the role of excitatory and inhibitory neurons in synchrony-generating mechanisms, in both epileptic and non-epileptic conditions. Abstract Understanding the role of different neuron types in synchrony generation is crucial for developing new therapies aiming to prevent hypersynchronous events such as epileptic seizures. Paroxysmal activity was linked to hyperexcitability and to bursting behaviour of pyramidal cells in animals. Human data suggested a leading role of either principal cells or interneurons, depending on the seizure morphology. In the present study, we aimed to uncover the role of excitatory and inhibitory processes in synchrony generation by analysing the activity of clustered single neurons during physiological and epileptiform synchronies in human neocortical slices. Spontaneous population activity was detected with a 24-channel laminar microelectrode in tissue derived from patients with or without preoperative clinical manifestations of epilepsy. This population activity disappeared by blocking GABAA receptors, and several variations of spatially and temporally simple or complex interictal-like spikes emerged in epileptic tissue, whereas peritumoural slices generated only simple spikes. Around one-half of the clustered neurons participated with an elevated firing rate in physiological synchronies with a slight dominance of excitatory cells. By contrast, more than 90% of the neurons contributed to interictal-like spikes and seizures, and an intense and synchronous discharge of inhibitory neurons was associated with the start of these events. Intrinsically bursting principal cells fired later than other neurons. Our data suggest that a balanced excitation and inhibition characterized physiological synchronies, whereas disinhibition-induced epileptiform events were initiated mainly by non-synaptically synchronized inhibitory neurons. Our results further highlight the differences between humans and animal models, and between in vivo and (pharmacologically manipulated) in vitro conditions.

The endocannabinoid system (ECS) has lately been proven to be an important, multifaceted homeostatic regulator, which influences a wide-variety of physiological processes all over the body. Its members, the endocannabinoids (eCBs; e.g., anandamide), the eCB-responsive receptors (e.g., CB1, CB2), as well as the complex enzyme and transporter apparatus involved in the metabolism of the ligands were shown to be expressed in several tissues, including the skin. Although the best studied functions over the ECS are related to the central nervous system and to immune processes, experimental efforts over the last two decades have unambiguously confirmed that cutaneous cannabinoid (“c[ut]annabinoid”) signaling is deeply involved in the maintenance of skin homeostasis, barrier formation and regeneration, and its dysregulation was implicated to contribute to several highly prevalent diseases and disorders, e.g., atopic dermatitis, psoriasis, scleroderma, acne, hair growth and pigmentation disorders, keratin diseases, various tumors, and itch. The current review aims to give an overview of the available skin-relevant endo- and phytocannabinoid literature with a special emphasis on the putative translational potential, and to highlight promising future research directions as well as existing challenges.

Colorectal sessile serrated adenomas (SSA) are hypothesized to be precursor lesions of an alternative, serrated pathway of colorectal cancer, abundant in genes with aberrant promoter DNA hypermethylation. In our present pilot study, we explored DNA methylation profiles and examined selected gene mutations in SSA. Biopsy samples from patients undergoing screening colonoscopy were obtained during endoscopic examination. After DNA isolation and quality analysis, SSAs (n = 4) and healthy controls (n = 5) were chosen for further analysis. DNA methylation status of 96 candidate genes was screened by q(RT)PCR using Methyl-Profiler PCR array system. Amplicons for 12 gene mutations were sequenced by GS Junior Instrument using ligated and barcoded adaptors. Analysis of DNA methylation revealed 9 hypermethylated genes in both normal and SSA samples. 12 genes (CALCA, DKK2, GALR2, OPCML, PCDH10, SFRP1, SFRP2, SLIT3, SST, TAC1, VIM, WIF1) were hypermethylated in all SSAs and 2 additional genes (BNC1 and PDLIM4) were hypermethylated in 3 out of 4 SSAs, but in none of the normal samples. 2 SSAs exhibited BRAF mutation and synchronous MLH1 hypermethylation and were microsatellite instable by immunohistochemical analysis. Our combined mutation and DNA methylation analysis revealed that there is a common DNA methylation signature present in pre-neoplastic SSAs. This study advocates for the use of DNA methylation as a potential biomarker for the detection of SSA; however, further investigation is needed to better characterize the molecular background of these newly recognized colorectal lesions.

The WNT signaling pathway has an essential role in colorectal carcinogenesis and progression, which involves a cascade of genetic and epigenetic changes. We aimed to analyze DNA methylation affecting the WNT pathway genes in colorectal carcinogenesis in promoter and gene body regions using whole methylome analysis in 9 colorectal cancer, 15 adenoma, and 6 normal tumor adjacent tissue (NAT) samples by methyl capture sequencing. Functional methylation was confirmed on 5-aza-2'-deoxycytidine-treated colorectal cancer cell line datasets. In parallel with the DNA methylation analysis, mutations of WNT pathway genes (APC, β-catenin/CTNNB1) were analyzed by 454 sequencing on GS Junior platform. Most differentially methylated CpG sites were localized in gene body regions (95% of WNT pathway genes). In the promoter regions, 33 of the 160 analyzed WNT pathway genes were differentially methylated in colorectal cancer vs. normal, including hypermethylated AXIN2, CHP1, PRICKLE1, SFRP1, SFRP2, SOX17, and hypomethylated CACYBP, CTNNB1, MYC; 44 genes in adenoma vs. NAT; and 41 genes in colorectal cancer vs. adenoma comparisons. Hypermethylation of AXIN2, DKK1, VANGL1, and WNT5A gene promoters was higher, while those of SOX17, PRICKLE1, DAAM2, and MYC was lower in colon carcinoma compared to adenoma. Inverse correlation between expression and methylation was confirmed in 23 genes, including APC, CHP1, PRICKLE1, PSEN1, and SFRP1. Differential methylation affected both canonical and noncanonical WNT pathway genes in colorectal normal-adenoma-carcinoma sequence. Aberrant DNA methylation appears already in adenomas as an early event of colorectal carcinogenesis.

Neural probes designed for extracellular recording of brain electrical activity are traditionally implanted with an insertion speed between 1 µm/s and 1 mm/s into the brain tissue. Although the physical effects of insertion speed on the tissue are well studied, there is a lack of research investigating how the quality of the acquired electrophysiological signal depends on the speed of probe insertion. In this study, we used four different insertion speeds (0.002 mm/s, 0.02 mm/s, 0.1 mm/s, 1 mm/s) to implant high-density silicon probes into deep layers of the somatosensory cortex of ketamine/xylazine anesthetized rats. After implantation, various qualitative and quantitative properties of the recorded cortical activity were compared across different speeds in an acute manner. Our results demonstrate that after the slowest insertion both the signal-to-noise ratio and the number of separable single units were significantly higher compared with those measured after inserting probes at faster speeds. Furthermore, the amplitude of recorded spikes as well as the quality of single unit clusters showed similar speed-dependent differences. Post hoc quantification of the neuronal density around the probe track showed a significantly higher number of NeuN-labelled cells after the slowest insertion compared with the fastest insertion. Our findings suggest that advancing rigid probes slowly (~1 µm/s) into the brain tissue might result in less tissue damage, and thus in neuronal recordings of improved quality compared with measurements obtained after inserting probes with higher speeds.

Decreased beta-amyloid clearance in Alzheimer's disease and increased blood-brain barrier permeability in aged subjects have been reported in several articles. However, morphological and functional characterization of blood-brain barrier and its membrane transporter activity have not been described in physiological aging yet. The aim of our study was to explore the structural changes in the brain microvessels and possible functional alterations of P-glycoprotein at the blood-brain barrier with aging. Our approach included MR imaging for anatomical orientation in middle aged rats, electronmicroscopy and immunohistochemistry to analyse the alterations at cellular level, dual or triple-probe microdialysis and SPECT to test P-glycoprotein functionality in young and middle aged rats. Our results indicate that the thickness of basal lamina increases, the number of tight junctions decreases and the size of astrocyte endfeet extends with advanced age. On the basis of microdialysis and SPECT results the P-gp function is reduced in old rats. With our multiparametric approach a complex regulation can be suggested which includes elements leading to increased permeability of blood-brain barrier by enhanced paracellular and transcellular transport, and factors working against it. To verify the role of P-gp pumps in brain aging further studies are warranted.

Revealing the current source distribution along the neuronal membrane is a key step on the way to understanding neural computations; however, the experimental and theoretical tools to achieve sufficient spatiotemporal resolution for the estimation remain to be established. Here, we address this problem using extracellularly recorded potentials with arbitrarily distributed electrodes for a neuron of known morphology. We use simulations of models with varying complexity to validate the proposed method and to give recommendations for experimental applications. The method is applied to in vitro data from rat hippocampus.

Revealing the membrane current source distribution of neurons is a key step on the way to understanding neural computations, however, the experimental and theoretical tools to achieve sufficient spatiotemporal resolution for the estimation remain to be established. Here we address this problem using extracellularly recorded potentials with arbitrarily distributed electrodes in a neuron of known morphology. We use simulations of models with varying complexity to validate the proposed method and to give recommendations for experimental applications. The method is applied to in vitro data from rat hippocampus.

Colorectal cancer (CRC) is a slow-developing cancer (10-15 years) with one of the highest frequencies in the world's population. Many countries have implemented various CRC screening programs, but have not achieved the desired compliance. Colonoscopy - considered the gold standard for CRC screening - has its limitations as well as the other techniques used, such as irrigoscopy, sigmoidoscopy, fecal blood and hemoglobin tests. The biomarker septin 9 has been found to be hypermethylated in nearly 100% of tissue neoplasia specimens and detected in circulating DNA fractions of CRC patients. A commercially available assay for septin 9 has been developed with moderate sensitivity (∼70%) and specificity (∼90%) and a second generation assay, Epi proColon 2.0 (Epigenomics AG), shows increased sensitivity (∼92%). The performance of the assay proved to be independent of tumor site and reaches a high sensitivity of 77%, even in early cancer stages (I and II). Furthermore, septin 9 was recently used in follow-up studies for detection of early recurrence of CRC. This article evaluates the opportunities, known limitations and future perspectives of the recently introduced Epi proColon(®) 2.0 test, which is based on the detection of aberrantly methylated DNA of the v2 region of the septin 9 gene in plasma.

The interplay between gastric and intestinal transcription factors has an important impact on gastric carcinogenesis. We compared the gene expression of CDX1, CDX2, SOX2 and related downstream genes in tumour and tumour surrounding gastric tissue of 48 gastric cancer patients with 30 healthy controls. There was no difference of gene expression of CDX1 and CDX2 between tumour or tumour-adjacent and tumour-distant mucosa, but both factors were significantly higher expressed in cancer patients compared with controls (p

Neural interface technologies including recording and stimulation electrodes are currently in the early phase of clinical trials aiming to help patients with spinal cord injuries, degenerative disorders, strokes interrupting descending motor pathways, or limb amputations. Their lifetime is of key importance; however, it is limited by the foreign body response of the tissue causing the loss of neurons and a reactive astrogliosis around the implant surface. Improving the biocompatibility of implant surfaces, especially promoting neuronal attachment and regeneration is therefore essential. In our work, bioactive properties of implanted black polySi nanostructured surfaces (520–800 nm long nanopillars with a diameter of 150–200 nm) were investigated and compared to microstructured Si surfaces in eight-week-long in vivo experiments. Glial encapsulation and local neuronal cell loss were characterised using GFAP and NeuN immunostaining respectively, followed by systematic image analysis. Regarding the severity of gliosis, no significant difference was observed in the vicinity of the different implant surfaces, however, the number of surviving neurons close to the nanostructured surface was higher than that of the microstructured ones. Our results imply that the functionality of implanted microelectrodes covered by Si nanopillars may lead to improved long-term recordings.

To determine the level of cell-free DNA (cfDNA), Septin 9 (SEPT9) and tumor markers (CEA, AFP, CA19–9, TPA, CA72–4). Plasma samples were collected four times a day (06:00, 12:00, 18:00, 24:00) from 9 patients with CRC (5 stage I-II, 4 stage III-IV), from one with colorectal adenoma and from one healthy control. CfDNA was isolated, quantified and bisulfite-converted. CfDNA and methylated SEPT9 were determined by RT-PCR. Plasma levels of conventional tumor markers were also measured. The lowest cfDNA concentrations were observed at 24:00 and 18:00 in stage I-III patients. In stage IV samples low cfDNA level (mean 48.2 ng/ml) were observed at several time points (6:00, 12:00, 18:00). The highest cfDNA levels were measured at 6:00 and 12:00 in CRC I-III stages and at 24:00 in stage IV samples (78.65 ng/ml). Higher in-day differences were found in stage II (43–48%) than in stage I samples (22%). Interestingly, the highest SEPT9 methylation level was found at 24:00 in most CRC cases, in contrast to the cfDNA levels. At 24:00, all cancer and adenoma cases were positive for SEPT9 methylation. At other time points (6:00, 12:00, 18:00) only 77.7% of CRC samples showed SEPT9 positivity. Stage I samples were SEPT9 positive only at 24:00. CEA and CA19–9 levels displayed correlation with the amount of cfDNA in case of late stage cases. Daytime activity can influence SEPT9 positivity in cases with low concentration of cfDNA. Thus, it may improve screening sensitivity by collecting samples earlier in the morning.

© 2015, Springer-Verlag Berlin Heidelberg. Synaptic reorganization in the epileptic hippocampus involves altered excitatory and inhibitory transmission besides the rearrangement of dendritic spines, resulting in altered excitability, ion homeostasis, and cell swelling. The potassium-chloride cotransporter-2 (KCC2) is the main chloride extruder in neurons and hence will play a prominent role in determining the polarity of GABAAreceptor-mediated chloride currents. In addition, KCC2 also interacts with the actin cytoskeleton which is critical for dendritic spine morphogenesis, and for the maintenance of glutamatergic synapses and cell volume. Using immunocytochemistry, we examined the cellular and subcellular levels of KCC2 in surgically removed hippocampi of temporal lobe epilepsy (TLE) patients and compared them to control human tissue. We also studied the distribution of KCC2 in a pilocarpine mouse model of epilepsy. An overall increase in KCC2-expression was found in epilepsy and confirmed by Western blots. The cellular and subcellular distributions in control mouse and human samples were largely similar; moreover, changes affecting KCC2-expression were also alike in chronic epileptic human and mouse hippocampi. At the subcellular level, we determined the neuronal elements exhibiting enhanced KCC2 expression. In epileptic tissue, staining became more intense in the immunopositive elements detected in control tissue, and profiles with subthreshold expression of KCC2 in control samples became labelled. Positive interneuron somata and dendrites were more numerous in epileptic hippocampi, despite severe interneuron loss. Whether the elevation of KCC2-expression is ultimately a pro- or anticonvulsive change, or both—behaving differently during ictal and interictal states in a context-dependent manner—remains to be established.

Rhythmic slow waves characterize brain electrical activity during natural deep sleep and under anesthesia, reflecting the synchronous membrane potential fluctuations of neurons in the thalamocortical network. Strong evidence indicates that the neocortex plays an important role in the generation of slow wave activity (SWA), however, contributions of individual cortical layers to the SWA generation are still unclear. The anatomically correct laminar profiles of SWA were revealed under ketamine/xylazine anesthesia, with combined local field potential recordings, multiple-unit activity (MUA), current source density (CSD) and time-frequency analyses precisely co-registered with histology. The up-state related negative field potential wave showed the largest amplitude in layer IV, the CSD was largest in layers I and III, whereas MUA was maximal in layer V, suggesting spatially dissociated firing and synaptic/transmembrane processes in the rat somatosensory cortex. Up-state related firing could start in virtually any layers (III-VI) of the cortex, but were most frequently initiated in layer V. However, in a subset of experiments, layer IV was considerably active in initiating up-state related MUA even in the absence of somatosensory stimulation. Somatosensory stimulation further strengthened up-state initiation in layer IV. Our results confirm that cortical layer V firing may have a major contribution to the up-state generation of ketamine/xylazine-induced SWA, however, thalamic influence through the thalamorecipient layer IV can also play an initiating role, even in the absence of sensory stimulation.