Two distinct neural circuits calculate the direction of incoming sound in mammals. Lower frequency sounds are processed in the medial superior olive (MSO) and higher frequencies are processed in the lateral superior olive (LSO); together they constitute the superior olivary complex. We show that the spike generation mechanisms of coincidence detection (CD) are employed in both these branches of sound localization pathway. Our description uses the concepts of probabilistic spike generation and spike timing jitter. We explain the notch in sound localization sensitivity described in human psychophysics. We estimate the processing time in the superior olivary complex and discuss possible spike processing mechanisms. Among them, we distinguish between the excitatory coincidence detection (ECD) and the inhibitory coincidence detection (ICD). We compare the latter to the mechanism of firing rate subtraction traditionally attributed to the lateral superior olive.

• MeSH
• akční potenciály * MeSH
• lokalizace zvuku * MeSH
• modely neurologické MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

PURPOSE: Localizing breast lesions by marking tumors and their detection using probes during surgery is a common part of clinical practice. Various nonwire localization systems were intended to be compared from different perspectives. METHODS: Various measurement experiments were performed. Localization techniques, including radioactive seed (RSLS), magnetically guided (MGLS), or radar (SLS), were compared in signal propagation in water and tissue environments, signal interference by surgical instruments, and the practical experience of surgeons. Individual experiments were thoroughly prospectively planned. RESULTS: The RSLS signal was detectable at the largest evaluated distance, ie, 60 mm. The SLS and MGLS signal detection was shorter, up to 25 mm to 45 mm and 30 mm, respectively. The signal intensity and the maximum detection distance in water differed slightly depending on the localization marker orientation to the probe, especially for SLS and MGLS. Signal propagation in the tissue was noted to a depth of 60 mm for RSLS, 50 mm for SLS, and 20 mm for MGLS. Except for the expected signal interferences by approaching surgical instruments from any direction for MGLS, the signal interruption for RSLS and SLS was observed only by inserting instruments directly between the localization marker and probe. Moreover, the SLS signal interference by instrument touch was noted. Based on surgeons' results, individual systems did not differ significantly for most measurement condition settings. CONCLUSION: Apparent differences noted among localization systems can help experts choose an appropriate system for a specific situation or reveal small nuances that have not yet been observed in clinical practice.

• Klíčová slova
• Lesion localization, Magnetically guided localization, Radar localization, Radioactive seed localization,
• MeSH
• lidé MeSH
• mikrochirurgie MeSH
• nádory prsu * diagnostické zobrazování   chirurgie   patologie   MeSH
• prsy patologie   MeSH
• segmentální mastektomie metody   MeSH
• voda MeSH
• zaměřovací značky pro radioterapii MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• voda MeSH

In this paper, the authors introduce an algorithm for locating sound-producing fish in a small rectangular tank that can be used, e.g., in behavioral bioacoustical studies to determine which fish in a group is sound-producing. The technique consists of locating a single sound source in the tank using signals gathered by four hydrophones placed in the tank together with a group of fish under study. The localization algorithm used in this paper is based on a ratio of two spectra ratios: the spectra ratio between the sound pressure measured by hydrophones at two locations and the spectra ratio between the theoretical Green's functions at the same locations. The results are compared to a localization based on image processing technique and with video recordings acquired synchronously with the acoustic recordings.

• MeSH
• akustika MeSH
• Batrachoidiformes fyziologie   MeSH
• lokalizace zvuku fyziologie   MeSH
• motorová vozidla MeSH
• pohyb těles MeSH
• ryby MeSH
• teoretické modely MeSH
• voda * MeSH
• vokalizace zvířat fyziologie   MeSH
• zvířata MeSH
• zvuk * MeSH
• zvuková spektrografie metody   MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• voda * MeSH

Caspase-2 is an apical protease responsible for the proteolysis of cellular substrates directly involved in mediating apoptotic signaling cascades. Caspase-2 activation is inhibited by phosphorylation followed by binding to the scaffolding protein 14-3-3, which recognizes two phosphoserines located in the linker between the caspase recruitment domain and the p19 domains of the caspase-2 zymogen. However, the structural details of this interaction and the exact role of 14-3-3 in the regulation of caspase-2 activation remain unclear. Moreover, the caspase-2 region with both 14-3-3-binding motifs also contains the nuclear localization sequence (NLS), thus suggesting that 14-3-3 binding may regulate the subcellular localization of caspase-2. Here, we report a structural analysis of the 14-3-3ζ:caspase-2 complex using a combined approach based on small angle X-ray scattering, NMR, chemical cross-linking, and fluorescence spectroscopy. The structural model proposed in this study suggests that phosphorylated caspase-2 and 14-3-3ζ form a compact and rigid complex in which the p19 and the p12 domains of caspase-2 are positioned within the central channel of the 14-3-3 dimer and stabilized through interactions with the C-terminal helices of both 14-3-3ζ protomers. In this conformation, the surface of the p12 domain, which is involved in caspase-2 activation by dimerization, is sterically occluded by the 14-3-3 dimer, thereby likely preventing caspase-2 activation. In addition, 14-3-3 protein binding to caspase-2 masks its NLS. Therefore, our results suggest that 14-3-3 protein binding to caspase-2 may play a key role in regulating caspase-2 activation. DATABASE: The atomic coordinates and structure factors have been deposited in the Protein Data Bank, www.ww pdb.org (PDB ID codes 6GKF and 6GKG).

• Klíčová slova
• 14-3-3 protein, caspase-2, fluorescence, nuclear localization sequence, protein-protein interactions, small angle X-ray scattering,
• MeSH
• cysteinové endopeptidasy chemie   metabolismus   MeSH
• fosforylace MeSH
• jaderné lokalizační signály * MeSH
• kaspasa 2 chemie   metabolismus   MeSH
• konformace proteinů MeSH
• lidé MeSH
• maloúhlový rozptyl MeSH
• molekulární modely MeSH
• proteiny 14-3-3 chemie   metabolismus   MeSH
• vazba proteinů MeSH
• vazebná místa MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• CASP2 protein, human MeSH Prohlížeč
• cysteinové endopeptidasy MeSH
• jaderné lokalizační signály * MeSH
• kaspasa 2 MeSH
• proteiny 14-3-3 MeSH

INTRODUCTION: For many years, the gold standard in the localization of non-palpable malignant breast tumors has been the use of wire-guided method. However, this has recently been replaced by more modern localization techniques in many institutions. METHODS: This is a retrospective case-control study comparing two localization techniques (iodine seed 125I and wire-guided localization) for localizing non-palpable tumors in patients with histologically verified breast carcinoma. RESULTS: The study included 62 patients - 31 with localization of malignant breast tumor by iodine seed (subgroup 125I) and 31 by wire-guided localization (subgroup FV). The average volume of the resected tissue in subgroup 125I (46.2 cm3) was statistically significantly smaller compared to subgroup FV (83.7 cm3; P = 0.0063). R0 resection was achieved in 29 cases (93.5%) in subgroup 125I and in 24 cases (77.4%) in subgroup FV (P = 0.0714). In subgroup 125I, re-resection was not indicated in any case, while in subgroup FV, re-resection due to tumor reaching the margin was indicated in 6 cases (19.4%; P = 0.01). CONCLUSION: Our initial experience show that the use of iodine seeds for localizing non-palpable breast tumors is associated with the removal of a smaller volume of resected tissue compared to wire-guided localization, with a trend towards more frequent achievement of R0 resection. In the subgroup of patients localized with iodine seeds, there was a smaller proportion of re-resections due to inadequate safety margins.

• Klíčová slova
• breast cancer, iodine seed, localizations techniques, wire-guided localization,
• MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• nádory prsu * chirurgie   diagnostické zobrazování   patologie   MeSH
• radioizotopy jodu * terapeutické užití   MeSH
• retrospektivní studie MeSH
• senioři MeSH
• studie případů a kontrol MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• Iodine-125 MeSH Prohlížeč
• radioizotopy jodu * MeSH

The asymmetric localization of biomolecules is critical for body plan development. One of the most popular model organisms for early embryogenesis studies is Xenopus laevis but there is a lack of information in other animal species. Here, we compared the early development of two amphibian species-the frog X. laevis and the axolotl Ambystoma mexicanum. This study aimed to identify asymmetrically localized RNAs along the animal-vegetal axis during the early development of A. mexicanum. For that purpose, we performed spatial transcriptome-wide analysis at low resolution, which revealed dynamic changes along the animal-vegetal axis classified into the following categories: profile alteration, de novo synthesis and degradation. Surprisingly, our results showed that many of the vegetally localized genes, which are important for germ cell development, are degraded during early development. Furthermore, we assessed the motif presence in UTRs of degraded mRNAs and revealed the enrichment of several motifs in RNAs of germ cell markers. Our results suggest novel reorganization of the transcriptome during embryogenesis of A. mexicanum to converge to the similar developmental pattern as the X. laevis.

• Klíčová slova
• Ambystoma mexicanum, RNA localization, TOMO-seq, animal-vegetal axis, early development,
• Publikační typ
• časopisecké články MeSH

OBJECTIVE: When considering all patients with focal drug-resistant epilepsy, as high as 40-50% of patients suffer seizure recurrence after surgery. To achieve seizure freedom without side effects, accurate localization of the epileptogenic tissue is crucial before its resection. We investigate an automated, fast, objective mapping process that uses only interictal data. METHODS: We propose a novel approach based on multiple iEEG features, which are used to train a support vector machine (SVM) model for classification of iEEG electrodes as normal or pathologic using 30 min of inter-ictal recording. RESULTS: The tissue under the iEEG electrodes, classified as epileptogenic, was removed in 17/18 excellent outcome patients and was not entirely resected in 8/10 poor outcome patients. The overall best result was achieved in a subset of 9 excellent outcome patients with the area under the receiver operating curve = 0.95. CONCLUSION: SVM models combining multiple iEEG features show better performance than algorithms using a single iEEG marker. Multiple iEEG and connectivity features in presurgical evaluation could improve epileptogenic tissue localization, which may improve surgical outcome and minimize risk of side effects. SIGNIFICANCE: In this study, promising results were achieved in localization of epileptogenic regions by SVM models that combine multiple features from 30 min of inter-ictal iEEG recordings.

• Klíčová slova
• Connectivity, Drug resistant epilepsy, Epileptogenic zone localization, High frequency oscillations, Machine learning, Multi-feature approach,
• MeSH
• dospělí MeSH
• elektroencefalografie přístrojové vybavení   metody   MeSH
• epilepsie parciální diagnóza   patofyziologie   MeSH
• implantované elektrody MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• retrospektivní studie MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Interaural time differences (ITDs), the differences of arrival time of the sound at the two ears, provide a major cue for low-frequency sound localization in the horizontal plane. The first nucleus involved in the computation of ITDs is the medial superior olive (MSO). We have modeled the neural circuit of the MSO using a stochastic description of spike timing. The inputs to the circuit are stochastic spike trains with a spike timing distribution described by a given probability density function (beta density). The outputs of the circuit reproduce the empirical firing rates found in experiment in response to the varying ITD. The outputs of the computational model are calculated numerically and these numerical simulations are also supported by analytical calculations. We formulate a simple hypothesis concerning how sound localization works in mammals. According to this hypothesis, there is no array of delay lines as in the Jeffress' model, but the inhibitory input is shifted in time as a whole. This is consistent with experimental observations in mammals.

• MeSH
• akustická stimulace MeSH
• lidé MeSH
• lokalizace zvuku * MeSH
• neurony fyziologie   MeSH
• savci MeSH
• sluchová dráha fyziologie   MeSH
• stochastické procesy MeSH
• teoretické modely * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The oocyte is a unique cell, from which develops a complex organism comprising of germ layers, tissues and organs. In some vertebrate species it is known that the asymmetrical localization of biomolecules within the oocyte is what drives the spatial differentiation of the daughter cells required for embryogenesis. This asymmetry is first established to produce an animal-vegetal (A-V) axis which reflects the future specification of the ectoderm, mesoderm, and endoderm layers. Several pathways for localization of vegetal maternal transcripts have already been described using a few animal models. However, there is limited information about transcripts that are localized to the animal pole, even though there is accumulating evidence indicating its active establishment. Here, we performed comparative TOMO-Seq analysis on two holoblastic cleavage models: Xenopus laevis and Acipenser ruthenus oocytes during oogenesis. We found that there were many transcripts that have a temporal preference for the establishment of localization. In both models, we observed vegetal transcript gradients that were established during either the early or late oogenesis stages and transcripts that started their localization during the early stages but became more pronounced during the later stages. We found that some animal gradients were already established during the early stages, however the majority were formed during the later stages of oogenesis. Some of these temporally localized transcripts were conserved between the models, while others were species specific. Additionally, temporal de novo transcription and also degradation of transcripts within the oocyte were observed, pointing to an active remodeling of the maternal RNA pool.

• Klíčová slova
• Acipenser ruthenus, RNA localization, TOMO-Seq, Xenopus laevis, oogenesis,
• Publikační typ
• časopisecké články MeSH

In oocytes, RNA localization has critical implications, as assembly of proteins in particular subcellular domains is crucial to embryo development. The distribution of mRNA molecules can identify and characterize localized transcripts. The goal of this study was to clarify the origin of primordial germ cells in the oocyte body plan and to reveal the generation of cell lineages by localized RNAs. The distribution of 12 selected mRNAs in sterlet Acipenser ruthenus oocytes was investigated by qPCR tomography and compared with known patterns of mRNA localization in Xenopus laevis. We investigated the distribution of two gene clusters in the ooplasm along the animal-vegetal axis of the sturgeon oocyte, both of which showed clearly defined intracellular gradient pattern remarkably similar to their distribution in the frog oocyte. We elucidated the localization of sturgeon egg germplasm markers belonging to the vegetal group of mRNAs. The mRNAs coding otx1, wnt11, and veg1 found to be localized in the sturgeon animal hemisphere are, in contrast, distributed in the vegetal hemisphere in amphibian. Actinopterygii and Sarcopterygii, two major lineages of osteichthyan vertebrates, split about 476 Ma (Blair & Hedges, ), albeit basal lineages share conserved biological features. Acipenseriformes is one the most basal living lineages of Actinopterygii, having evolved about 200 Ma (Bemis, Birstein, & Waldman, ), contemporaneous with modern amphibians (Roelants et al., ).

• Klíčová slova
• RNA localization, acipenser ruthenus, oocyte, primordial Germ Cells, qPCR, sturgeon, xenopus laevis,
• MeSH
• biologická evoluce MeSH
• druhová specificita MeSH
• messenger RNA fyziologie   MeSH
• oocyty fyziologie   MeSH
• ryby * MeSH
• transport proteinů fyziologie   MeSH
• Xenopus * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• messenger RNA MeSH