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A serine/threonine-specific protein kinase B (PKB), also known as Akt, is a key factor in the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway that regulates cell survival, metabolism and proliferation. Akt phosphorylates many downstream specific substrates, which subsequently control the nuclear envelope breakdown (NEBD), centrosome maturation, spindle assembly, chromosome segregation, and cytokinesis. In vertebrates, Akt is also an important player during oogenesis and preimplantation development. In the signaling pathways regulating mRNA translation, Akt is involved in the control of mammalian target of rapamycin complex 1 (mTORC1) and thereby regulates the activity of a translational repressor, the eukaryotic initiation factor 4E (eIF4E) binding protein 1 (4E-BP1). In this review, we summarize the functions of Akt in mitosis, meiosis and early embryonic development. Additionally, the role of Akt in the regulation of mRNA translation is addressed with respect to the significance of this process during early development. [ABSTRACT FROM AUTHOR]

Cells are equipped with a diverse network of signaling and regulatory proteins that function as cell cycle regulators and checkpoint proteins to ensure the proper progression of cell division. A key regulator of cell division is polo-like kinase 1 (PLK1), a member of the serine/threonine kinase family that plays an important role in regulating the mitotic and meiotic cell cycle. The phosphorylation of specific substrates mediated by PLK1 controls nuclear envelope breakdown (NEBD), centrosome maturation, proper spindle assembly, chromosome segregation, and cytokinesis. In mammalian oogenesis, PLK1 is essential for resuming meiosis before ovulation and for establishing the meiotic spindle. Among other potential roles, PLK1 regulates the localized translation of spindle-enriched mRNAs by phosphorylating and thereby inhibiting the translational repressor 4E-BP1, a downstream target of the mTOR (mammalian target of rapamycin) pathway. In this review, we summarize the functions of PLK1 in mitosis, meiosis, and cytokinesis and focus on the role of PLK1 in regulating mRNA translation. However, knowledge of the role of PLK1 in the regulation of meiosis remains limited. [ABSTRACT FROM AUTHOR]

Sirtuins (e.g. human Sirt1-7) catalyze the removal of acyl groups from lysine residues in proteins in an NAD1-dependent manner, and loss of sirtuin deacylase activity correlates with the development of aging-related diseases. Although multiple reports suggest that sirtuin activity is regulated by oxidative post-translational modifications of cysteines during inflammation and aging, no systematic comparative study of potential direct sirtuin cysteine oxidative modifications has been performed. Here, using IC50 and kinact/KI analyses, we quantified the ability of nitrosothiols (S-nitrosoglutathione and S-nitroso-N-acetyl-D,L-penicillamine), nitric oxide, oxidized GSH, and hydrogen peroxide to post-translationally modify and inhibit the deacylase activity of Sirt1, Sirt2, Sirt3, Sirt5, and Sirt6. The inhibition was correlated with cysteine modification and assessed with chemical-probe and blot-based assays for cysteine S-nitrosation, sulfenylation, and glutathionylation. We show that the primarily nuclear sirtuins Sirt1 and Sirt6, as well as the primarily cytosolic sirtuin Sirt2, are modified and inhibited by cysteine S-nitrosation in response to exposure to both free nitric oxide and nitrosothiols (kinact/KI = 5 M 21 s21), which is the first report of Sirt2 and Sirt6 inhibition by S-nitrosation. Surprisingly, the mitochondrial sirtuins Sirt3 and Sirt5 were resistant to inhibition by cysteine oxidants. Collectively, these results suggest that nitric oxide-derived oxidants may causatively link nuclear and cytosolic sirtuin inhibition to aging-related inflammatory disease development. [ABSTRACT FROM AUTHOR]

Background: Continuous enzyme kinetic assays are often used in high-throughput applications, as they allow rapid acquisition of large amounts of kinetic data and increased confidence compared to discontinuous assays. However, data analysis is often rate-limiting in high-throughput enzyme assays, as manual inspection and selection of a linear range from individual kinetic traces is cumbersome and prone to user error and bias. Currently available software programs are specialized and designed for the analysis of complex enzymatic models. Despite the widespread use of initial rate determination for processing kinetic data sets, no simple and automated program existed for rapid analysis of initial rates from continuous enzyme kinetic traces. Results: An Interactive Continuous Enzyme Kinetics Analysis Tool (ICEKAT) was developed for semi-automated calculation of initial rates from continuous enzyme kinetic traces with particular application to the evaluation of Michaelis-Menten and EC50/IC50 kinetic parameters, as well as the results of high-throughput screening assays. ICEKAT allows users to interactively fit kinetic traces using convenient browser-based selection tools, ameliorating tedious steps involved in defining ranges to fit in general purpose programs like Microsoft Excel and Graphpad Prism, while still maintaining simplicity in determining initial rates. As a test case, we quickly analyzed over 500 continuous enzyme kinetic traces resulting from experimental data on the response of the protein lysine deacetylase SIRT1 to small-molecule activators. Conclusions: ICEKAT allows simultaneous visualization of individual initial rate fits and the resulting Michaelis-Menten or EC50/IC50 kinetic model fits, as well as hits from high-throughput screening assays. In addition to serving as a convenient program for practicing enzymologists, ICEKAT is also a useful teaching aid to visually demonstrate in real-time how incorrect initial rate fits can affect calculated Michaelis-Menten or EC50/IC50 kinetic parameters. For the convenience of the research community, we have made ICEKAT freely available online at https://icekat.herokuapp.com/icekat. [ABSTRACT FROM AUTHOR]

Although the involvement of the extracellular signal-regulated kinases 1 and 2 (ERK1/2) pathway in the regulation of cytostatic factor (CSF) activity; as well as in microtubules organization during meiotic maturation of oocytes; has already been described in detail; rather less attention has been paid to the role of ERK1/2 in the regulation of mRNA translation. However; important data on the role of ERK1/2 in translation during oocyte meiosis have been documented. This review focuses on recent findings regarding the regulation of translation and the role of ERK1/2 in this process in the meiotic cycle of mammalian oocytes. The specific role of ERK1/2 in the regulation of mammalian target of rapamycin (mTOR); eukaryotic translation initiation factor 4E (eIF4E) and cytoplasmic polyadenylation element binding protein 1 (CPEB1) activity is addressed along with additional focus on the other key players involved in protein translation. [ABSTRACT FROM AUTHOR]

The crucian carp Carassius carassius (Linnaeus, 1758), is native to many European freshwaters. Despite its wide distribution, the crucian carp is declining in both the number and sizes of populations across much of its range. Here we studied 30 individuals of a putative pure population from Helsinki, Finland. Despite clear external morphological features of C. carassius, an individual was of a higher ploidy level than the others. We therefore applied a set of molecular genetic (S7 nuclear and cytochrome b mitochondrial genes) and cytogenetic tools (sequential fluorescent 4’, 6-diamidino-2-phenylindole [DAPI], Chromomycin A3 [CMA3], C-banding and in situ hybridization [FISH] with both 5S and 28S ribosomal DNA probes) to determine its origin. While all examined characteristics of a diploid representative male (CCAHe2Fi) clearly corresponded to those of C. carassius, a triploid individual (CCAHe1Fi) was more complex. Phylogenetic analysis revealed that the nuclear genome of CCAHe1Fi contained three haploid sets: two C. gibelio and one C. carassius. However the mitochondrial DNA was that of C. gibelio, demonstrating its hybrid origin. The FISH revealed three strong (more intensive) 5S rDNA loci, confirming the triploid status, and an additional 24 weak (less intensive) signals were observed in the chromosome complement of CCAHe1Fi. On the other hand, only two strong and 16 weak 5S rDNA signals were visible on the chromosomes of the CCAHe2Fi male. 28S rDNA FISH revealed four strong signals in both CCAHe1Fi and CCAHe2Fi individuals. CMA3 staining revealed four to six CMA3-positive bands of CCAHe1Fi, while that of diploids contained only two to four. The fact that a polyploid hybrid Carassius female with a strong invasive potential may share morphological characters typical for endangered C. carassius highlights a need to combine genetic investigations of Carassius cryptic diversity with conservation measures of C. carassius in Europe. [ABSTRACT FROM AUTHOR]

The question was whether a canyon-shaped reservoir is inhabited by genetically distinct populations of European perch Perca fluviatilis exhibiting different spatial behaviour, or by a single population. The study was conducted in the spring of 2006 at Římov Reservoir, Czech Republic. Epipelagic and bathypelagic perch fry ( EPF and BPF) were captured by trawl net (mesh size 1 × 1.35 mm) controlled by echo sounder, and littoral perch fry and adults ( LPF and LPA) were caught by electrofishing and beach seine (mesh size 1 × 1.35 mm). DNA was isolated in 266 individuals from the reservoir, and phylogenetic analysis based on mt DNA was performed ( n = 18) on BPF, EPF, LPF, and LPA from the reservoir and additional sequences from Central Europe. Six microsatellites were used for differentiating among communities ( n = 266). There was no evidence for genetic divergence in mt DNA sequences. Analyses of microsatellites revealed no statistically significant variations between spatial communities, and confirmed genetic homogeneity among communities. FST values and the number of genetic clusters point to the same conclusion, i.e., the reservoir is inhabited by a single population whose individuals occupy different microhabitats. [ABSTRACT FROM AUTHOR]

The sirtuin family of proteins catalyze the NAD+-dependent deacylation of acyl-lysine residues. Humans encode seven sirtuins (Sirt1-7), and recent studies have suggested that posttranslational modification of Sirt1 by cysteine S-nitrosation correlates with increased acetylation of Sirt1 deacetylase substrates. However, the mechanism of Sirt1 inhibition by S-nitrosation was unknown. Here, we show that Sirt1 is transnitrosated and inhibited by the physiologically relevant nitrosothiol S-nitrosoglutathione. Steady-state kinetic analyses and binding assays were consistent with Sirt1 S-nitrosation inhibiting binding of both the NAD+ and acetyl-lysine substrates. Sirt1 S-nitrosation correlated with Zn2 release from the conserved sirtuin Zn2+-tetrathiolate and a loss of α-helical structure without overall thermal destabilization of the enzyme. Molecular dynamics simulations suggested that Zn2+ loss due to Sirt1 S-nitrosation results in repositioning of the tetrathiolate subdomain away from the rest of the catalytic domain, thereby disrupting the NAD+ and acetyl-lysine-binding sites. Sirt1 S-nitrosation was reversed upon exposure to the thiol-based reducing agents, including physiologically relevant concentrations of the cellular reducing agent glutathione. Reversal of S-nitrosation resulted in full restoration of Sirt1 activity only in the presence of Zn2+, consistent with S-nitrosation of the Zn2+-tetrathiolate as the primary source of Sirt1 inhibition upon S-nitrosoglutathione treatment. [ABSTRACT FROM AUTHOR]

It has been previously shown that multimeric pentraxin 3 (PTX3) is a key component of the cumulus oophorus extracellular matrix (ECM) in mice. In response to the ovulatory LH surge, the cumulus cells assemble a unique ECM that envelopes the oocyte and cumulus cell complex. Importantly, cumuli from PTX3 −/− mice were defective in their ECM organization and their fertility was impaired. It has been demonstrated that tumor necrosis factor alpha–induced protein 6 catalyzes the formation of heavy chains of (inter-alpha-trypsin inhibitor) -hyaluronan complexes and these are then cross-linked via PTX3. This process is tightly regulated and requires the proteins to meet/interact in the correct order. Finally, in this way, the above-listed proteins form the cumulus oophorus ECM. We investigated whether PTX3 is expressed in the porcine preovulatory follicle. Porcine oocyte-cumulus complexes (OCC) and mural granulosa cells (MGC) from gilts were obtained either after stimulation in vivo with eCG/hCG (4, 8, 16, 24, and 32 h) or culture in vitro (4, 24, and 44 h) in FSH/LH-supplemented medium. The methods performed were real-time reverse transcriptase-polymerase chain reaction, Western blot analysis, and immunostaining. The expression of PTX3 transcripts was significantly increased 24 h after either in vivo hCG stimulation or in vitro FSH/LH treatment in both OCC and MGC. Western blot analysis with PTX3 antibody revealed that not only matrix extracts from in vivo-stimulated gilts contain high levels of PTX3 protein but also matrix extracts of FSH/LH-stimulated OCC cultured in medium supplemented either with follicular fluid or with porcine serum. The localization of PTX3 in the cumulus oocyte complex was confirmed by immunostaining. In conclusion, PTX3 is produced by porcine OCC and MGC both in vivo and in vitro with gonadotropin stimuli inducing cumulus expansion. [ABSTRACT FROM AUTHOR]

This work investigates the effects of semicrystaline poly(1-butene) on amorphous polylactide in relation to mechanical, thermal and rheological properties. The blends were prepared by melt mixing, and poly(1-butene) content ranged from 5 to 40 wt %. It was found that 5 wt % poly(1-butene) heightened impact strength by more than double, however, other mechanical properties decreased. Poly(1-butene) significantly affected the glass transition temperature of polylactide, while the melting temperature of blends with 5 and 15 wt % poly(1-butene) slightly decreased. Thermogravimetric measurements revealed that the thermal stability of polylactide improved if poly(1-butene) was present, and rheological properties exhibited enhanced complex viscosity in combination with dynamic moduli. [ABSTRACT FROM AUTHOR]

Key message: The impact of the D genome and QTL in the A and B genomes on agronomic performance of hexaploid wheat and tetraploid durum was determined using novel recombinant inbred line populations derived from interploid crosses. Abstract: Genetic differences between common hexaploid (6X) bread wheat ( Triticum aestivum, 2 n = 6 x = 42, genome, AABBDD) and tetraploid (4X) durum wheat ( T. turgidum subsp. durum, 2 n = 4 x = 28, genome, AABB) may exist due to effects of the D genome and allelic differences at loci in the A and B genomes. Previous work allowed identification of a 6X by 4X cross combination that resulted in a large number of fertile recombinant progeny at both ploidy levels. In this study, interspecific recombinant inbred line populations at both 4X and 6X ploidy with 88 and 117 individuals, respectively, were developed from a cross between Choteau spring wheat (6X) and Mountrail durum wheat (4X). The presence of the D genome in the 6X population resulted in increased yield, tiller number, kernel weight, and kernel size, as well as a decrease in stem solidness, test weight and seed per spike. Similar results were found with a second RIL population containing 152 lines from 18 additional 6X by 4X crosses. Several QTL for agronomic and quality traits were identified in both the 4X and 6X populations. Although negatively impacted by the lack of the D genome, kernel weight in Mountrail (4X) was higher than Choteau (6X) due to positive alleles from Mountrail on chromosomes 3B and 7A. These and other favorable alleles may be useful for introgression between ploidy levels. [ABSTRACT FROM AUTHOR]

We studied growth characteristics of three different spatial groups (epipelagic, bathypelagic, and littoral) of European perch ( Perca fluviatilis) fry occurring simultaneously in Římov Reservoir, Czech Republic. We used the body size analysis as long-term growth indicator and RNA/DNA ratio as short-term growth indicators. The minimum body size as well as minimum RNA/DNA ratio, was found in bathypelagic perch fry (15.7 ± 1.8 and 1.89 ± 0.63 mm, respectively). The littoral perch fry was the biggest with the highest RNA/DNA ratio (19.3 ± 1.5 and 2.53 ± 0.59 mm, respectively). The intermediate values and high variation in both body size and RNA/DNA ratio was found in the epipelagic group (16.9 ± 2.3 and 2.36 ± 0.78 mm, respectively). These results refer to the presence of uniformity in the bathypelagic and littoral groups, and a possible mixing of individuals from different groups in epipelagic zone. Our findings suggest that the spatial distribution of perch fry is most likely dynamic system of continuous shifting of individuals among different groups. [ABSTRACT FROM AUTHOR]

This paper presents a method for direct and alternating current electrospinning of polymeric solutions of three less common polyamides (nylons). Homopolyamide PA 8, heteropolyamide PA 6|9 and semi-aromatic amide (phthalamide) PA 6(3)T were dissolved in the formic acid and dichloromethane mixture, which have proved to be a suitable solvent for various other linear polyamides. The dependence of the viscosity, electrical conductivity, and spinnability via the direct (DC) and alternating current (AC) technology on the solution concentration was observed. Scanning electron microscope images of the prepared nanofibers were acquired and consequently analyzed for fiber defects, followed by measuring the fiber diameters. The differences in the nanofiber quality of DC layers and AC plumes were discussed. Finally, the optimal concentrations for the electrospinning of the examined solutions were determined. The communication follows our previous work and extends the number of electrospinnable polyamides, thus facilitating future research in this area. [ABSTRACT FROM AUTHOR]

A comparative cytogenetic analysis was carried out in five species of a monophyletic clade of neotropical Cichlasomatine cichlids, namely Cleithracara maronii Steindachner, 1881, Ivanacara adoketa (Kullander & Prada-Pedreros, 1993), Nannacara anomala Regan, 1905, N. aureocephalus Allgayer, 1983 and N. taenia Regan, 1912. Karyotypes and other chromosomal characteristics were revealed by CDD banding and mapped onto the phylogenetic hypothesis based on molecular analyses of four genes, namely cyt b, 16S rRNA, S7 and RAG1. The diploid numbers of chromosomes ranged from 44 to 50, karyotypes were composed predominantly of monoarmed chromosomes and one to three pairs of CMA3 signal were observed. The results showed evolutionary reduction in this monophyletic clade and the cytogenetic mechanisms (fissions/fusions) were hypothesized and discussed. [ABSTRACT FROM AUTHOR]

Fish usually have a simple body shape and many morphological characters can be easily obtained by 2-dimensional image analysis. Measuring errors are often analyzed using data from several researchers or repeated measurements, but the testing of accuracy and repeatability based on different methods has rarely been examined. Here we report the comparison of manual measurements using Proma 150D digital calipers and computer-assisted image analysis in LUCIA software to evaluate the accuracy of both methods and the suitability of digital images for exploration of fish morphology. Eighteen morphometric characters of 20 specimens of Prussian carp were examined by 2 researchers. The mean of the relative bias within and between researchers separately for the manual and computerassisted methods (expressed as a percentage of a character's value) varied from -4.27% to 9.48%. Comparison of interresearcher results using digital caliper, interresearcher results using LUCIA, intraresearcher results using digital caliper, and the 2 methods using manual caliper and LUCIA revealed significant differences in several characters. Only testing of intraresearcher relative bias using LUCIA showed no significant difference. [ABSTRACT FROM AUTHOR]

The karyotype and other chromosomal characteristics the crucian carp (Carassius carassius (Linnaeus, 1758)) were revealed by means of conventional banding protocols (C, CMA3, AgNOR). The diploid chromosome number (2n) in this species was 100. Its karyotype was composed of 10 pairs of metacentric, 18 pairs of submetacentric and 22 pairs of subtelo- to acrocentric chromosomes without any microchromosomes. C-banding identified blocks of telomeric heterochromatin on seven chromosome pairs. The NORs were situated on the p arms of the 14th pair of submetacentric chromosomes and on the p arms of the 32nd pair of subtelo-acrocentric chromosomes; AgNOR-positive signals corresponded to the CMA3-positive signals. These chromosome characteristics may suggest a paleo-allotetraploid origin of C. carassius genome. [ABSTRACT FROM AUTHOR]

A single female with 206 chromosomes and another 26 females with 156 chromosomes identified as Prussian carp, Carassius gibelio, and 5 individuals with 100 chromosomes identified as crucian carp, C. carassius, were sampled during field survey in one locality in the upper Elbe River. To identify the origin of females with high chromosome numbers, comparative karyotype analysis, GISH, with whole C. carassius DNA as probe and phylogenetic positions of sampled individuals revealed by cytochrome b mitochondrial marker were performed. GISH showed consistently bright labeling of 50 chromosomal elements out of 206, corresponding to the haploid chromosome number of C. carassius. The position of these females with high chromosome numbers in a reconstructed phylogenetic tree was within the clade of C. gibelio, documenting its affiliation to C. gibelio mitochondrial, i.e. maternal lineage. Our findings indicated that the mother of the female with high chromosome numbers was a gynogenetically reproducing 156-chromosome C. gibelio female and the father a bisexually reproducing C. carassius male. We, therefore, hypothesized that the C. gibelio × C. carassius allopolyploid female with 206 chromosomes arose by a mechanism of sperm genome addition to an unreduced egg of the mother. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The headwaters of five large African river basins flow through the Bié Plateau in Angola and still remain faunistically largely unexplored. We investigated fish fauna from the Cuanza and Okavango-Zambezi river systems from central Angola. We reconstructed molecular phylogenies of the most common cichlid species from the region, Tilapia sparrmanii and Serranochromis macrocephalus, using both mitochondrial and nuclear markers. We found evidence for ichthyofaunal contact and gene flow between the Cuanza and Okavango-Zambezi watersheds in the Bié Plateau in central Angola. Waterfalls and rapids also appeared to restrict genetic exchange among populations within the Cuanza basin. Further, we found that the Angolan Serranochromis cichlid fishes represent a monophyletic lineage with respect to other haplochromines, including the serranochromines from the Congo and Zambezi rivers. This study represents an important initial step in a biodiversity survey of this extremely poorly explored region, as well as giving further understanding to species distributions and gene flow both between and within river basins. [ABSTRACT FROM AUTHOR]

Abstract: Freshwater fishes of the genus Carassius, widespread throughout Europe and Asia, are important aquaculture fishes and include the world''s most important pet fish, the goldfish. The high morphologic similarity between the species, however, has up to now prevented reliable conclusions on their taxonomy, biogeography and introduction history. A phylogeny of the fish genus Carassius based on the cytochrome b sequence of 404 specimens collected from aquaculture and open water localities across Eurasia identifies most of the presently recognised species as monophyletic lineages, but also that at least one lineage exists that does not correspond to any described species. Within Europe, feral populations of Carassius auratus occur mainly in the Mediterranean area and Great Britain, while Carassius gibelio is found in most of non-Mediterranean Europe and some localities in Italy. Carassius langsdorfii has very scattered points of occurrence in at least six European countries. C. auratus and C. langsdorfii are not native to Europe. The populations of C. gibelio in eastern Central Europe and parts of Eastern Europe are considered as resulting from a natural postglacial range expansion, while the rest of Europe was colonised due to anthropogenic impact. The presence of diploid (2n=100) as well as triploid (3n=150) specimens in the three most widespread species indicates that ploidy level is not a character to identify the species of Carassius. A remarkably low genetic divergence in C. gibelio can be the result of clone selection in the gynogenetic populations. In general, our data present the first comprehensive overview about the genus Carassius in Europe based on genetic data. [Copyright &y& Elsevier]

In this study, records on the occurrence of the Japanese ginbuna Carassius langsdorfii from northern Germany, north-western Italy and southern Bosnia and Herzegovina are presented. The new findings, in addition to former studies reported in the Czech Republic and Greece, show that C. langsdorfii is much more widespread in Europe than was previously believed. [ABSTRACT FROM AUTHOR]

J. Neurochem. (2012) 122, 523-536. Abstract The nerve growth factor (NGF) precursor, proNGF, is implicated in various neuropathological states. ProNGF signals apoptosis by forming a complex with the receptors p75 and sortilin, however, it can also induce neurite growth, proposed to be mediated by the receptor of mature NGF, tyrosine kinase receptor A (TrkA). The way in which these dual effects occur in adult neurons is unclear. We investigated the neurotrophic effects of proNGF on peptidergic sensory neurons isolated from adult mouse dorsal root ganglia and found that proNGF stimulated neurite extension and branching, requiring p75, sortilin and TrkA. Neurite growth rarely occurred in sortilin-expressing neurons but was commonly observed in TrkA-positive, sortilin-negative neurons that associated closely with sortilin-positive glia. ProNGF was unable to induce local trophic effects at growth cones where sortilin-positive glia was absent. We propose that in adult sensory neurons the neurotrophic response to proNGF is mediated by NGF and TrkA, and that peri-somatic glia may participate in sortilin- and p-75 dependent cleavage of proNGF. The potential ability of local glial cells to provide a targeted supply of NGF may provide an important way to promote trophic (rather than apoptotic) outcomes under conditions where regeneration or sprouting is required. [ABSTRACT FROM AUTHOR]

The freshwater characiform fish Prochilodus lineatus is a detritivorous species that has its native distribution area in South America but has been imported to China for aquaculture purposes. This is the first time that it is being reported in Vietnam, both from aquaculture and captured from a river channel. According to local authorities, the species is becoming increasingly important in local aquaculture and its spread can be expected. Keeping in mind the high biomass production in the rivers of its native distribution area, a successful establishment of P. lineatus into Vietnamese fresh waters may exert serious impacts on the local ecosystems. [ABSTRACT FROM AUTHOR]

Introduction of genes from outside a primary germplasm base has the potential to impact phenotypic diversity, genetic structure, and patterns of linkage disequilibrium (LD). Our goals were to monitor the introduction of key genes in a hard red spring wheat (Triticum aestivum L.) germplasm set using historical cultivars, to determine the impact of the introduced genes on phenotypic diversity in elite germplasm, and to assess the impact of selection history on LD. A superior allele for bread making was introduced early in the 20th century and quickly became fixed. An allele for solid stems introduced in the mid 20th century is the major source of variation in current germplasm. An introduced allele for photoperiod insensitivity is an important source of variation for heading date in current germplasm. The allelic introductions impacted patterns of LD. The unlinked loci for reduced height, RHT-B1 and RHT-D1, were in LD. Linkage disequilibrium for physically linked markers near introduced genes did not exceed previous estimates of genome-wide LD. Our results showed a pattern of gene introductions into the spring wheat germplasm base that continues to have an impact on phenotypic diversity and patterns of LD. [ABSTRACT FROM AUTHOR]

The article discusses the karyotype diversity of the fish offspring from silver Prussian carp diploid male and triploid female. An overview of the specie's karyotype that features supernumerary chromosomes of the triploid biotype is offered. It reports that the male fish has 100 while the female has 159 which show high level of chromosomal plasticity of the biotype.

Abstract: Spinal cord injury (SCI) is a major cause of persistent neuropathic pain of central origin. Recent evidence suggests neuropathic pain in clinically complete SCI patients correlates with limited sensory function below the lesion (sensory discomplete). On this basis we examined if the onset of mechanical hyperalgesia was different in rodents after a severe incomplete clip-compression SCI versus a complete spinal cord transection at thoracic segment T13. Above-level withdrawal behaviors evoked by forepaw stimulation provided evidence of mechanical hyperalgesia after incomplete but not complete SCI, whereas below-level responses evoked by hindpaw stimulation revealed hypersensitivity after both injuries. The latency of the above-level response was 4–5 wks but was longer after a moderate clip-compression injury. Mechanical hyperalgesia was fully reversed by three analgesic drugs used in treating neuropathic SCI pain, but their duration of action differed significantly, showing a rank order of amitriptyline (24–48h)≫morphine (6h)>gabapentin (2h). Evidence of central sensitization in cervical spinal cord segments that receive sensory projections from the forelimbs was provided by immunohistochemistry for Zif268, a functional marker of neuroplasticity. Zif268-immunoreactive neurons in laminae I/II increased in response to repetitive noxious forepaw stimulation in the incomplete SCI group, and this response was reduced in the complete transection and sham-operated groups. These data are consistent with the hypothesis that neuropathic pain of cord origin is more likely to develop after SCI when there is an incomplete loss of axons traversing the lesion. [Copyright &y& Elsevier]

The objective of this study was to develop a fast, reliable and cost effective photographic documentation tool to complement identification methods on preserved material. We tested the applicability of a flatbed desktop scanner as an easy means to provide a voucher in form of a whole body image for further morphological analysis. Similar species of European perch and zander were included in the test trial, accompanied by molecular genetic analysis as reference identification. The outcome of the study reveals the general utility of the method. [ABSTRACT FROM AUTHOR]

Abstract: Goldfish is one of the most important pet and laboratory fishes of the world that is nowadays pan-globally distributed and well known to everybody. Despite the wide phenotypic variability of the ornamental forms, all goldfish are traditionally considered to be Carassius auratus, a species that developed via domestication from the Silver Prussian carp, C. gibelio. However, the postulated monophyly of goldfish has never been proven, and multiple domestication events may have occurred. Here we present the results of a reconstructed genealogy of 49 individuals of the genus Carassius based on unique sequences of mitochondrial gene cytochrome b. The samples originated from different parts of Eurasia and include different varieties of domesticated goldfish as well as feral populations and specimens of other representatives of the genus Carassius. The results indicate that goldfish indeed forms a monophyletic lineage and point on a single domestication event as source of all goldfish varieties. However, the monophyletic goldfish lineage was not nested within the samples of C. gibelio, but formed a sister lineage. [Copyright &y& Elsevier]

Abstract: A conditioning lesion improves regeneration of central and peripheral axons of dorsal root ganglion (DRG) neurons after a subsequent injury by enhancing intrinsic growth capacity. This enhanced growth state is also observed in cultured DRG neurons, which support a more sparsely and rapidly elongating mode of growth after a prior conditioning lesion in vivo. Here we examined differences in the capacity or requirements of specific types of sensory neurons for regenerative growth, which has important consequences for development of strategies to improve recovery after injury. We showed that after partial or complete injury of the sciatic nerve in mice, an elongating mode of growth in vitro was activated only in DRG neurons that did not express calcitonin gene-related peptide (CGRP) or bind Bandeiraea simplicifolia I-isolectin B4 (IB4). We also directly examined the response of conditioned sensory neurons to nerve growth factor (NGF), which does not enhance growth in injured peripheral nerves in vivo. We showed that after partial injury, NGF stimulated a highly branched and linearly restricted rather than elongating mode of growth. After complete injury, the function of NGF was impaired, which immunohistochemical studies of DRG indicated was at least partly due to downregulation of the NGF receptor, tropomyosin-related kinase A (TrkA). These results suggest that, regardless of the type of conditioning lesion, each type of DRG neuron has a distinct intrinsic capacity or requirement for the activation of rapidly elongating growth, which does not appear to be influenced by NGF. [Copyright &y& Elsevier]

Morphological, cytogenetic and molecular genetic identification of two specimens of Carassius langsdorfii from the upper Elbe basin is given. Probably, the species was introduced by accident with commercial fish imports. Potentially, this introduced species may be of harm to native fish species. [ABSTRACT FROM AUTHOR]

Objective: Chronic lung disease caused by volutrauma is one of the most important consequences of preterm delivery. In this pilot study a new method is presented that consists of flushing part of the dead space with fresh gas in order to reduce high tidal volumes, the chief cause of volutrauma. The aim of the study was to evaluate if the new method could reduce ventilatory effort in preterm infants by diminishing dead space.Design and Setting: In split-flow ventilation, gas required for dead-space washout is split off from the regular ventilation circuit. The split flow bypasses the apparatus dead space and fills it retrogradely with fresh breathing gas, mainly in the pause between exhalation and inspiration. The mean per-minute ventilation and ventilation index after 12 h of conventional ventilation were compared with corresponding mean values after 12 h of split-flow ventilation in 17 preterm infants weighing <2,000 g. Statistical analysis was performed using the T -test for matched pairs.Results: After switching from conventional ventilation to split-flow ventilation, the mean per-minute ventilation per kilogram of body weight decreased significantly from a mean value of 0.314+/-0.097 l/kg/min to 0.190+/-0.043 l/kg/min ( p <0.001), while the ventilation index decreased significantly from 28.47+/-7.48 to 16.10+/-4.13 ( p <0.001).Conclusion: Split-flow ventilation significantly reduces apparatus dead space during ventilation in preterm infants. This leads to reduced ventilatory effort. [ABSTRACT FROM AUTHOR]

Instrumental dead space (iDS) is a major part of total dead space in newborns, and thus significantly determines effective alveolar ventilation. Continuous tracheal gas insufflation (CTGI) is a method for reducing the role of iDS, allowing a reduction in respiratory support and secondary lung injury. The literature and authors' experience with the method are reviewed. Major attention is paid to the risks in providing CTGI, optimal equipment and optimal management of CTGI. [ABSTRACT FROM AUTHOR]

Instrumental dead space (iDS) is a major part of total dead space in newborns, and thus significantly determines effective alveolar ventilation. Continuous tracheal gas insufflation (CTGI) is a method for reducing the role of iDS, allowing a reduction in respiratory support and secondary lung injury. The literature and authors' experience with the method are reviewed. Major attention is paid to the risks in providing CTGI, optimal equipment and optimal management of CTGI. [ABSTRACT FROM AUTHOR]

[Display omitted] • The surface energy of the fibre layers is affected by the frequency of alternating current spinning. • The frequency of alternating current spinning can be used to control the wetting of the fibre layers. • From the surface tension and surface energy, we can predict the contact angle. The study addresses the modification of the wetting of fibrous layers of polycaprolactone via alternating current spinning. The production of the fibre layers considered in the study was initiated using a function generator. The shifting of the offset to the limits of the transmitted amplitude resulted in the production of wettable fibrous layers with high surface energy values. The study revealed that the frequency of alternating spinning affects the surface energy value. Thus, by changing the alternating spinning frequency, it is possible to change the wettability of the produced fibre layers. The study concluded that it is possible to predict the contact angle via the application of the Kwok-Neumann model, as well as the use of the surface tension values of the gelatin hydrogel and the surface energies of the fibre layers produced. [ABSTRACT FROM AUTHOR]

Recent years have observed a significant increase in the use of degradable materials in medicine due to their minimal impact on the patient and broad range of applicability. The biodegradable polymer Polydioxanone (PDO) provides a good example of the use of such one polymer that can represent the aforementioned medical materials in the field of medicine, due to its high level of biocompatibility and interesting mechanical properties. PDO is used to produce absorbable medical devices such as sutures and stents, and is also suitable for the fabrication of certain orthopedic implants. Polydioxanone can be processed using the injection molding method due to its thermoplastic nature; this method allows for the precise and easily-controllable production of medical materials without the need for toxic additives. A number of small commercial polymer implants have recently been introduced onto the market based on this processing method. It is important to note that, to date, no relevant information on the molding of PDO is available either for the scientific or the general public, and no study has been published that describes the potential of the injection molding of PDO. Hence, we present our research on the basic technological and material parameters that allow for the processing of PDO using the laboratory microinjection molding method. In addition to determining the basic parameters of the process, the research also focused on the study of the structural and mechanical properties of samples based on the thermal conditions during processing. A technological frame work was successfully determined for the processing of PDO via the microinjection molding approach that allows for the production of samples with the required homogeneity, shape stability and surface quality in a laboratory scale. The research revealed that PDO is a polymer with a major share of crystalline phases, and that it is sensitive to the annealing temperature profile in the mold, which has the potential to impact the final crystalline structure, the fracture morphology and the mechanical properties. [ABSTRACT FROM AUTHOR]

The electrospinning process that produces fine nanofibrous materials have a major disadvantage in the area of productivity. However, alternating current (AC) electrospinning might help to solve the problem via the modification of high voltage signal. The aforementioned productivity aspect can be observed via a camera system that focuses on the jet creation area and that measures the average lifespan. The paper describes the optimization of polyamide 6 (PA 6) solutions and demonstrates the change in the behavior of the process following the addition of a minor dose of oxoacid. This addition served to convert the previously unspinnable (using AC) solution to a high-quality electrospinning solution. The visual analysis of the AC electrospinning of polymeric solutions using a high-speed camera and a programmable power source was chosen as the method for the evaluation of the quality of the process. The solutions were exposed to high voltage applying two types of AC signal, i.e., the sine wave and the step change. All the recordings presented in the paper contained two sets of data: firstly, camera recordings that showed the visual expression of electrospinning and, secondly, signal recordings that provided information on the data position in the signal function. [ABSTRACT FROM AUTHOR]

Presents the results of a survey of policy initiatives in vocational education and training in the Czech Republic. Description of the characteristics and developments of vocational education before and after 1989; Insufficient attention given to system-level changes; Need for greater coordination and strategic policy-making at regional and national levels.

• The spinning of polymers using alternating current power source can be difficult. • Previously unspinnable solution of PA 6 was modified and successfully electrospun. • The relation between the quality of spinning and diameter of nanofibers was examined. The experiment addressed the alternating current (AC) electrospinning of polyamide 6 (PA 6) solutions composed of organic acids, which are commonly employed in direct current (DC) electrospinning systems. Initial testing revealed that it is not possible to AC spin ordinary PA 6 solutions so as to provide a product that can be used in subsequent material experiments. The solutions were enriched with oxoacids, which led to the improvement of the spinning process. The solutions were tested by means of both a viscometer and conductivity meter. The layers so produced were scanned using a SEM microscope. Each of the materials was analyzed for the purpose of the provision of statistical data. [ABSTRACT FROM AUTHOR]

Sexual vs. asexual reproduction—unisexual vs. bisexual populations—diploid vs. polyploid biotypes—genetic vs. environmental sex determination: all these natural phenomena are associated with the genus of teleost fish, Carassius. This review places emphasis on two Carassius entities with completely different biological characteristics: one globally widespread and invasive Carassius gibelio, and the other C. carassius with a decreasing trend of natural occurrence. Comprehensive biological and cytogenetic knowledge of both entities, including the physical interactions between them, can help to balance the advantages of highly invasive and disadvantages of threatened species. For example, the benefits of a wide-ranged colonization can lead to the extinction of native species or be compensated by parasitic enemies and lead to equilibrium. This review emphasizes the comprehensive biology and cytogenetic knowledge and the importance of the Carassius genus as one of the most useful experimental vertebrate models for evolutionary biology and genetics. Secondly, the review points out that effective molecular cytogenetics should be used for the identification of various species, ploidy levels, and hybrids. The proposed investigation of these hallmark characteristics in Carassius may be applied in conservation efforts to sustain threatened populations in their native ranges. Furthermore, the review focuses on the consequences of the co-occurrence of native and non-native species and outlines future perspectives of Carassius research. [ABSTRACT FROM AUTHOR]

Cyclin dependent kinase 1 (CDK1) has been primarily identified as a key cell cycle regulator in both mitosis and meiosis. Recently, an extramitotic function of CDK1 emerged when evidence was found that CDK1 is involved in many cellular events that are essential for cell proliferation and survival. In this review we summarize the involvement of CDK1 in the initiation and elongation steps of protein synthesis in the cell. During its activation, CDK1 influences the initiation of protein synthesis, promotes the activity of specific translational initiation factors and affects the functioning of a subset of elongation factors. Our review provides insights into gene expression regulation during the transcriptionally silent M-phase and describes quantitative and qualitative translational changes based on the extramitotic role of the cell cycle master regulator CDK1 to optimize temporal synthesis of proteins to sustain the division-related processes: mitosis and cytokinesis. [ABSTRACT FROM AUTHOR]

The paper provides a description of the potential for the direct current- and alternating current-driven electrospinning of various linear aliphatic polyamides (PA). Sets with increasing concentrations of selected PAs were dissolved in a mixture of formic acid and dichloromethane at a weight ratio of 1:1 and spun using a bar electrode applying direct and alternating high voltage. The solubility and spinnability of the polyamides were investigated and scanning electron microscopy (SEM) images were acquired of the resulting nanofiber layers. The various defects of the spun fibers and their diameters were detected and subsequently measured. Moreover, the dynamic viscosity and conductivity were also subjected to detailed investigation. The most suitable concentrations for each of the PAs were determined according to previous findings, and the solutions were spun using a NanospiderTM device at the larger scale. The fiber diameters of these samples were also measured. Finally, the surface energy of the fiber layers produced by the NanospiderTM device was measured aimed at selecting a suitable PA for a particular application. [ABSTRACT FROM AUTHOR]

Social deprivation early in life affects further individual development and leads to irreversible behavioural alterations later in life. Although the syndrome is well-studied in vertebrates including humans, its presence in invertebrates has been described only in eusocial insects and cockroaches. Here we show the first evidence of social deprivation in subsocial decapod crustaceans, based on analysis of video-recorded agonistic encounters of juvenile red swamp crayfish (Procambarus clarkii, Girard). In comparison with maternally incubated juveniles, isolated crayfish had altered repertoires, numbers and frequency of agonistic interactions similar to those described in vertebrates. Our results support the view on the syndrome of social deprivation as a ubiquitous trait in species with developed maternal care across diverse taxa. [ABSTRACT FROM AUTHOR]

Nanotechnologies allow the production of yarns containing nanofibres for use in composites, membranes and biomedical materials. Composite yarns with a conventional thread core for mechanical strength and a nanofibrous envelope for functionality, e.g. biological, catalytic, have many advantages. Until now, the production of such yarns has been technologically difficult. Here, we show an approach to composite yarn production whereby a plume of nanofibers generated by high throughput AC needleless and collectorless electrospinning is wound around a classic thread. In the resulting yarn, nanofibres can form up to 80% of its weight. Our yarn production speed was 10 m/min; testing showed this can be increased to 60 m/min. After the yarn was embedded into knitwear, scanning electron microscope images revealed an intact nanofibrous envelope of the composite yarn. Our results indicate that this production method could lead to the widespread production and use of composite nanofibrous yarns on an industrial scale. [ABSTRACT FROM AUTHOR]

Afrotropical inland waters are highly diverse ecosystems; however, they remain poorly studied, especially for rotifers. Here, we contributed to the knowledge of the rotifer species richness in the largely understudied African countries of Angola and Ghana. We assessed the roles of habitat type and a suite of abiotic environmental factors in determining rotifer species richness of Ghana. A total of 37 sites (Ghana 32, Angola 5) in 19 water bodies from a variety of aquatic habitat types were sampled. In Ghana, we identified 118 taxa (105 species or subspecies level, 13 identified to genus). We identified 15 taxa (13 species) in the Angola samples. For Ghana, 100 of 118 (~85%) taxa were new records for the country, of which 13 species (~11%) were also new records for Africa. Nearly all the species (~93%) were new records for Angola. Species richness was positively correlated with conductivity and reservoir habitat type and negatively with pH. Redundancy analysis (RDA), conducted at the species level for the Ghana dataset, indicated suites of species associated with latitude, longitude, temperature, TDS, or pH. We also evaluated the effect of climate on species distribution in 27 African countries by conducting a review of all reports from Africa to determine factors associated with species richness. A Spearman's correlation confirmed a significant positive correlation between the number of rotifer species and the number of climatic regions (R = 0.53, p < 0.001) for certain countries, based on species distributions in relation to Köppen–Geiger climate regions. This fact validates the environmental heterogeneity hypothesis for African rotifers. Lastly, we predicted that rotifer species richness in Ghana, as a country with a tropical climate, could approach ~190 taxa, while in climatically heterogeneous Angola we predict ~200 taxa. This study contributes to our knowledge of rotifer biogeography and species richness patterns in Africa. [ABSTRACT FROM AUTHOR]

The use of digital data sources, such as social media, in iEcology has opened up new opportunities for research on species distribution and biological invasions. Invasive species can cause significant damage to biodiversity and ecosystem services, making early detection and intervention crucial. Ornamental fish species are a particular concern, as many have been imported to India for aquaria and have caused direct damage to local biodiversity. South American invasive catfish species belonging to the family Loricariidae have been introduced to many parts of the world outside their natural range, including India. Despite a lack of published records, this study used social media and internet sources to identify 28 sites of occurrence of suckermouth armoured catfish in the River Krishna basin across four Indian states. Through morphological and genetic analysis, the invasive loricariid fish collected from the River Krishna basin at Bhigwan was confirmed to be Pterygoplichthys pardalis. In addition, sentiment analysis of social media content and other internet sources revealed that 60.71% of individuals perceive the introduction of suckermouth armoured catfish to their region as a threat. This insight could prove advantageous as society is more likely to support eradication activities necessary to prevent further damage to the ecosystem. [ABSTRACT FROM AUTHOR]

We provide a general overview of spatial distribution and the economic situation of aquaculture enterprises in Czechia (the Czech Republic) in terms of revenues, profitability, work productivity, indebtedness and grants. We analysed data available in the State Veterinary Administration and information system of the State Agricultural Intervention Fund. The most significant fish producers (enterprises) are located in the regions of South Bohemia. Aquaculture sector profitability and enterprises profits have been moderately rising since 2010. The profitability in 2015 is roughly the same as that in 2005. The amount of provided grants showed a higher value than the generated average annual profits. The enterprises were not able to generate sufficient resources to finance investments without grants resources. Enterprises that realised financing for larger investments from bank credits showed relatively high levels of indebtedness (micro-enterprises at 95.5%). On the contrary, work productivity was the highest for micro-enterprises. Micro-enterprises had the largest share of revenues in relation to the number of employees. Each group of enterprises is considerably specific and needs an individual approach for the subsequent evaluation. [ABSTRACT FROM AUTHOR]

This article, published in Mediterranean Botany, discusses the discovery of a new species of Allium, a genus of flowering plants, in Bulgaria and Greece. The researchers collected population samples of an unknown species that appeared to be representative of the newly described species, Allium goumenissanum. Through various methods, including genetic, cytogenetic, and morphological analyses, the researchers confirmed that the unknown species was indeed A. goumenissanum. The study also expanded the known distribution of A. goumenissanum, including new localities in Greece and identifying it as a new taxon for Bulgaria. This document provides detailed information on the methods and procedures used in a study on Allium species. The study involved genetic analysis, chromosome counts, flow cytometry, and morphological and anatomical observations. The researchers used various techniques and software to analyze DNA sequences, determine ploidy levels, and examine the characteristics of different plant parts. The results of these analyses were compared to existing descriptions of related species. The document includes tables and figures that present the data and findings of the study. The text provides information on the morphology, genetics, and cytogenetics of Allium sp., specifically focusing on the identification and classification of the species. The study used molecular and cytogenetic analyses to determine that the populations of Allium sp. belong to A. goumenissanum. The study also compared the morphology, epidermal micromorphology, and leaf anatomy of the cultivated accessions [Extracted from the article]