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Abstract Membrane penetration by non-enveloped viruses is diverse and generally not well understood. Enteroviruses, one of the largest groups of non-enveloped viruses, cause diseases ranging from the common cold to life-threatening encephalitis. Enteroviruses enter cells by receptor-mediated endocytosis. However, how enterovirus particles or RNA genomes cross the endosome membrane into the cytoplasm remains unknown. Here we used cryo-electron tomography of infected cells to show that endosomes containing enteroviruses deform, rupture, and release the virus particles into the cytoplasm. Blocking endosome acidification with bafilomycin A1 reduced the number of particles that released their genomes, but did not prevent them from reaching the cytoplasm. Inhibiting post-endocytic membrane remodeling with wiskostatin promoted abortive enterovirus genome release in endosomes. The rupture of endosomes also occurs in control cells and after the endocytosis of very low-density lipoprotein. In summary, our results show that cellular membrane remodeling disrupts enterovirus-containing endosomes and thus releases the virus particles into the cytoplasm to initiate infection. Since the studied enteroviruses employ different receptors for cell entry but are delivered into the cytoplasm by cell-mediated endosome disruption, it is likely that most if not all enteroviruses, and probably numerous other viruses from the family Picornaviridae, can utilize endosome rupture to infect cells.

Undifferentiated carcinoma with osteoclast-like giant cells (UCOGC) of the pancreas represents a rare subtype of pancreatic ductal adenocarcinoma (PDAC). Despite a distinct morphology and specific clinical behavior, UCOGCs exhibit unexpected similarities in regard to DNA mutational profiles with conventional PDAC. Treating pancreatic ductal adenocarcinoma is particularly challenging, with limited prospects for cure. As with many other malignant neoplasms, the exploration of microRNAs (miRNAs, miRs) in regulating the biological characteristics of pancreatic cancer is undergoing extensive investigation to enhance tumor diagnostics and unveil the therapeutic possibilities. Herein, we evaluated the expression of miR-21, -96, -148a, -155, -196a, -210, and -217 in UCOGCs and poorly differentiated (grade 3, G3) PDACs. The expression of miR-21, miR-155, and miR-210 in both UCOGCs and G3 PDACs was significantly upregulated compared to the levels in normal tissue, while the levels of miR-148a and miR-217 were downregulated. We did not find any significant differences between cancerous and normal tissues for the expression of miR-96 and miR-196a in G3 PDACs, whereas miR-196a was slightly, but significantly, downregulated in UCOGCs. On the other hand, we have not observed significant differences in the expression of the majority of miRNAs between UCOGC and G3 PDAC, with the exception of miR-155. UCOGC samples demonstrated lower mean levels of miR-155 in comparison with those in G3 PDACs.

Undifferentiated carcinoma with osteoclast-like giant cells (UCOGC) of the pancreas is a rare malignancy regarded as a subvariant of pancreatic ductal carcinoma (PDAC) characterized by variable prognosis. UCOGC shows a strikingly similar spectrum of oncogenic DNA mutations to PDAC. In the current work, we analyzed the landscape of somatic mutations in a set of 13 UCOGC cases via next-generation sequencing (NGS). We detected a spectrum of pathogenic or likely pathogenic mutations similar to those observed in PDAC following previously published results (10 KRAS, 9 TP53, 4 CDKN2A, and 1 SMAD4, CIC, GNAS, APC, ATM, NF1, FBXW7, ATR, and FGFR3). Our results support the theory that UCOGC is a variant of PDAC, despite its unique morphology; however, a UCOGC-specific genomic signature as well as predictive markers remain mainly unknown. Programmed death ligand 1 (PD-L1) status remains an important predictive marker based on previous studies.

Insulin is stored in vivo inside the pancreatic β-cell insulin secretory granules. In vitro studies have led to an assumption that high insulin and Zn2+ concentrations inside the pancreatic β-cell insulin secretory granules should promote insulin crystalline state in the form of Zn2+-stabilized hexamers. Electron microscopic images of thin sections of the pancreatic β-cells often show a dense, regular pattern core, suggesting the presence of insulin crystals. However, the structural features of the storage forms of insulin in native preparations of secretory granules are unknown, because of their small size, fragile character and difficult handling. We isolated and investigated the secretory granules from MIN6 cells under near-native conditions, using cryo-electron microscopic (Cryo-EM) techniques. The analysis of these data from multiple intra-granular crystals revealed two different rhomboidal crystal lattices. The minor lattice has unit cell parameters (a ≃ b ≃ 84.0 Å, c ≃ 35.2 Å), similar to in vitro crystallized human 4Zn2+-insulin hexamer, whereas the largely prevalent unit cell has more than double c-axis (a ≃ b ≃ c ≃ 96.5 Å) that probably corresponds to two or three insulin hexamers in the asymmetric unit. Our experimental data show that insulin can be present in pancreatic MIN6 cell granules in a microcrystalline form, probably consisting of 4Zn2+-hexamers of this hormone.

This article investigates public spaces near urban rivers that contribute to the interaction between natural and urbanized areas and between people from different socio-economic backgrounds. The main goal of this study was to evaluate the environment of the largest urbanized areas of the Czech Republic, through which a large watercourse flows and creates a direct interaction with the city center. To evaluate the state of connectivity and comfort of urban rivers in the Czech Republic, a set of tools was applied to three cities: Prague, České Budějovice, and Hradec Králové. The methodology was created to correspond to the territory of Central Europe and was used for the specific assessment of rivers in four dimensions: (a) the spatial and visual accessibility, (b) the condition of the green corridor, (c) the condition of public space, and (d) the condition of the first built line. The dimensions are expressed using thirteen quantitative indicators of the environmental condition. The methodology uses the Urban River Sustainability Index (URSI), which was necessary to adjust the calculations of the indicators and resources for the Central European area. The best results were found in the central part of Prague and the worst in the peripheral part of Hradec Králové. The results call for the use of connectivity and comfort assessments of urban rivers for comparison, motivation, and future improvement in practice.

Genome release of enteroviruses relies on exposure to acidic pH, but the mechanism of uncoating remains unclear. Here, Buchta et al. show that echovirus 18 loses one to three adjacent capsid-protein pentamers, resulting in an opening of more than 120 Å for genome release.

Abstract Background Non-native species have aroused scientific interest because of their ability to successfully colonise areas to which they have been introduced, despite their sometimes limited genetic variation compared to their native range. These species establish themselves with the aid of some pre-existing features favouring them in the new environment. Pectinatella magnifica (Leidy, 1851), the freshwater magnificent bryozoan, is non-native in Europe and Asia. This study was designed to determine the genetic diversity and population structure of P. magnifica colonies collected from the Protected Landscape Area (PLA) and UNESCO Biosphere Reserve Třeboňsko (the Czech Republic) in the 2009 and 2011–2014 periods using Amplified Fragment Length Polymorphism (AFLP). Findings The vast majority of the examined non-native colonies, except three colonies sampled in 2012, expressed very low levels of genetic variation, not differentiating from the USA native colony. The Bayesian clustering approach grouped the 28 accessions into two genetically different populations. Conclusions The data suggest relatively low gene diversity within all colonies, which might reflect the recent expansion of P. magnifica in the Czech Republic.

The study focuses on how land use in the selected location affects the amount of phosphorus in the watershed. Defines the basic concepts of this and related issues. The monitored value is total phosphorus and description of the measuring apparatus. The resulting data are arranged in tables and graphs and results are compared with standards of Czech norms (CSN) and other similar studies.

Abstract We evaluated responses to the treatment and long‐term outcomes of chronic myeloid leukemia patients treated with imatinib as first‐line treatment in routine clinical setting from two countries with centralized tyrosine kinase inhibitors (TKIs) treatment. We assessed prognostic significance of European LeukemiaNet (ELN) 2006‐ and 2009‐defined responses and the prognostic value of molecular responses at defined time points on 5‐year survivals. Among the cumulative rates of incidence of hematologic, cytogenetic, and molecular responses and all important survival parameters, we evaluated the prognostic significance of different BCR‐ABL transcript‐level ratios (≤1%; >1%–≤10%; >10%) at 3, 6, 12, and 18 months (n = 199). The ELN optimal response criteria and their predictive role were significantly beneficial for event‐free survival at all given time points. We found significant improvement in survivals of patients with BCR‐ABL lower than 10% in the 6th and 12th months. Significantly better outcome was found in patients who achieved major molecular response (MMR) in the 12th month. The cumulative incidences of complete cytogenetic response (CCyR) and MMR were significantly associated with the molecular response in the 3rd month. The ELN response criteria and their predictive role were helpful at given time points; however, the 2009 definition did not significantly alter the prognostic accuracy compared with that of the 2006 definition. The significant value was observed for cytogenetic responses at the 6th and 12th month. Moreover, progression‐free and event‐free survivals were improved with MMR at the 12th month.

Abstract Bacterial spores owe their incredible resistance capacities to molecular structures that protect the cell content from external aggressions. Among the determinants of resistance are the quaternary structure of the chromosome and an extracellular shell made of proteinaceous layers (the coat), the assembly of which remains poorly understood. Here, in situ cryo-electron tomography on lamellae generated by cryo-focused ion beam micromachining provides insights into the ultrastructural organization of Bacillus subtilis sporangia. The reconstructed tomograms reveal that early during sporulation, the chromosome in the forespore adopts a toroidal structure harboring 5.5-nm thick fibers. At the same stage, coat proteins at the surface of the forespore form a stack of amorphous or structured layers with distinct electron density, dimensions and organization. By analyzing mutant strains using cryo-electron tomography and transmission electron microscopy on resin sections, we distinguish seven nascent coat regions with different molecular properties, and propose a model for the contribution of coat morphogenetic proteins.

This article focuses on land use changes in the area of interest in the southern part of the Czech Republic (South Bohemia Region). Land use changes have been assessed at several time levels over nearly two centuries. Unlike similar studies, two types of materials were used as source data and compared. Specifically, these are historical maps or aerial photographs and the Corine Land Cover database. The evolution of land use was examined on a representative set of sixty cadastral areas, which evenly cover the territory of three different production areas of the South Bohemia Region. Each production area was then evaluated both as a whole and separately. The paper’s results confirm the trend of decreasing the share of intensively used agricultural land (arable land), especially in worse natural conditions, like in other countries of the Central European region. An essential result of the publication was also the demonstration of the unique development of the post-1948 period when there was a significant difference in land use development between the border forage production areas and the rest of the agriculturally used parts of the region.

The aim of this article is to evaluate possible problems with small urban structures restoration and development. Based on SWOT analysis and landscape characteristics there the evaluation of potential changes in the village Záblatí u Prachatic. These changes were divided into three categories – housing and architecture, amenities and production. By potential development and revival of this village it is preferred to use existing capacities in all potential fields of development. The most important problems and barriers are missing or insufficient infrastructure, poor technical conditions of building sites and also problems with parking spaces. These problems are connected not only with this concrete village but with most of similar municipalities in this region.

In most areas, where land adjustments were completed, only a mild erosion threat was discoverd and planned against – erosive measures were consequently minimal in these areas. There was mostly the expulsion of maize from crop rotation, grassing or projection of a new rural road so as it interupts the slope. The land adjustment Horní Stropnice was chosen for a more detailed solution, there was a higher erosion threat discoverd by the calculation of soil deterioration. The area was split in blocks, in which soil deterioration was counted by means of Wischmeier-Smith equation for various values of factor R. Then soil deterioration after implementation of anti-erosive measures was calculated. The anti-erosive component measures were evaluated and their execution in the terrain was investigated. Results show a problem with the determination of the right value of factor R and in reality planned anti-erosive measures stay mostly unimplemented.

Nowadays, what is discussed more and more is the quality of land consolidation and the related need of a standard process being established, but also quality indicators. One possibility to ”measure” land consolidation efficiency is to make the connection between the original landscape frame, before land consolidation, and the final image of realized common equipment changes. Land consolidations which directly affect the landscape structure have the optimal degree of being global and reduce the very complicated phenomena in the environment and cultural landscape and also they have the most suitable of evaluating measures 1:5000, from which it is still possible to keep wider territorial links and also to solve property-law problems of cadastre.