The recently introduced orientation selective deep brain stimulation (OS-DBS) technique freely controls the direction of the electric field's spatial gradient by using multiple contacts with independent current sources within a multielectrode array. The goal of OS-DBS is to align the electrical field along the axonal track of interest passing through the stimulation site. Here we utilized OS-DBS with a planar 3-channel electrode for stimulating the rat entorhinal cortex (EC) and medial septal nucleus (MSN), two promising areas for DBS treatment of Alzheimer's disease. The brain responses to OS-DBS were monitored by whole brain functional magnetic resonance imaging (fMRI) at 9.4 T with Multi-Band Sweep Imaging with Fourier Transformation (MB-SWIFT). Varying the in-plane OS-DBS stimulation angle in the EC resulted in activity modulation of multiple downstream brain areas involved in memory and cognition. Contrary to that, no angle dependence of brain activations was observed when stimulating the MSN, consistent with predictions based on the electrode configuration and on the main axonal directions of the targets derived from diffusion MRI tractography and histology. We conclude that tuning the OS-DBS stimulation angle modulates the activation of brain areas relevant to Alzheimer's disease, thus holding great promise in the DBS treatment of the disease.
- MeSH
- Alzheimer Disease * diagnostic imaging therapy MeSH
- Entorhinal Cortex diagnostic imaging physiology MeSH
- Deep Brain Stimulation * methods MeSH
- Cognition MeSH
- Rats MeSH
- Magnetic Resonance Imaging methods MeSH
- Brain MeSH
- Septal Nuclei * MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Research Support, N.I.H., Extramural MeSH
Carbamazepine is an antiepileptic drug with a narrow therapeutic index, which requires an efficient method for blood level monitoring. Finger-prick dried blood spot (DBS) collection is an alternative microsampling technique, which is less invasive than conventional venipuncture. Paper-based molecularly imprinted-interpenetrating polymer networks (MI-IPN) were developed as blood collection devices, which allowed for selective on-spot microextraction of carbamazepine from DBS. A hybrid of homogeneous polystyrene and silica gel polymer was synthesized and coated on a Whatman® Grade 1 filter paper. Proteins and other interferences in the blood samples were eliminated by using the MI-IPN collection devices, and the resulting DBS extracts were suitable for direct injection into the capillary electrophoretic instrument. The lower limit of quantitation of 4 μg/mL in capillary blood was achieved by the sweeping-micellar electrokinetic chromatography method using a KCl-containing matrix, which was sufficient for the therapeutic drug monitoring purposes. Method accuracies were in the range of 88.4 ± 4.5% to 94.5 ± 2.7% with RSD values ≤ 5.1%. The developed paper-based MI-IPN provided superior extraction efficiencies (92.2 ± 2.5%) in comparison with commercially available DBS collection cards, i.e., Whatman® 903 protein saver card (59.8 ± 2.8%) and GenCollect™ 2.0 card (47.2 ± 1.4%). The paper-based MI-IPN devices for DBS collection and on-spot extraction were characterized by simple fabrication, low costs, disposability, and reduction in sample preparation steps, and their further developments might open new perspectives in clinical applications, such as in therapeutic drug monitoring. Graphical abstract.
- MeSH
- Anticonvulsants blood isolation & purification MeSH
- Electrophoresis, Capillary methods MeSH
- Carbamazepine blood isolation & purification MeSH
- Humans MeSH
- Solid Phase Microextraction methods MeSH
- Molecularly Imprinted Polymers chemistry MeSH
- Drug Monitoring MeSH
- Blood Specimen Collection methods MeSH
- Paper MeSH
- Tandem Mass Spectrometry MeSH
- Dried Blood Spot Testing methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
A new simple electrochemical immunosensor approach for the determination of antibodies to tick-borne encephalitis virus (TBEV) in immunological products was developed and tested. The assay is performed by detecting the silver reduction signal in the bioconjugates with antibodies (Ab@AgNP). Here, signal is read by cathodic linear sweep voltammetry (CLSV) through the detection of silver chloride reduction on a gold-carbon composite electrode (GCCE). Covalent immobilization of the antigen on the electrode surface was performed after thiolation and glutarization of the GCCE. Specific attention has been paid to the selection of conditions for stabilizing both the silver nanoparticles and their Ab@AgNP. A simple flocculation test with NaCl was used to select the concentration of antibodies, and the additional stabilizer bovine serum albumin (BSA) was used for Ab@AgNP preparation. The antibodies to TBEV were quantified in the range from 50 IU·mL-1 to 1600 IU·mL-1, with a detection limit of 50 IU·mL-1. The coefficient of determination (r2) is 0.989. The electrochemical immunosensor was successfully applied to check the quality of immunological products containing IgG antibodies to TBEV. The present work paves the path for a novel method for monitoring TBEV in biological fluids.
- MeSH
- Electrochemical Techniques methods MeSH
- Electrodes MeSH
- Immunoassay methods MeSH
- Encephalitis, Tick-Borne diagnosis immunology MeSH
- Metal Nanoparticles chemistry ultrastructure MeSH
- Antibodies, Viral immunology MeSH
- Serum Albumin, Bovine MeSH
- Cattle MeSH
- Spectrophotometry, Ultraviolet MeSH
- Silver chemistry MeSH
- Particle Size MeSH
- Encephalitis Viruses, Tick-Borne immunology MeSH
- Animals MeSH
- Check Tag
- Cattle MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
The ecology of earwigs in natural forest ecosystems is poorly understood. We used sweeping to determine the population densities of adult earwigs, by sex and species, on ten tree species in a temperate floodplain forest in southern Moravia (Czech Republic). We also determined the relationships between the properties of tree species and earwig density and diet as indicated by digestive tract contents. The densities and diet composition of earwigs differed between the three detected earwig species [Apterygida media (Hagenbach, 1822), Chelidurella acanthopygia (Genè, 1832) and Forficula auricularia Linnaeus, 1758] and among tree species. Earwig densities were related to lichen coverage and fungal coverage on the trees. The diet of earwigs was associated with specific leaf area, herbivore damage to the leaves, and light exposure of the trees. A. media was the most abundant of the three earwig species. Although the contents of its digestive tract changed depending on available food resources, A. media appeared to preferentially consume soft-bodied insect herbivores and fungi associated with wounds caused by herbivores rather than plant material. Therefore, this species has the potential to help reduce the population densities of soft-bodied pests of forest trees.
... Landscapeof campaigns 37 -- 3.2.1 Website and brand social media sweep 37 -- 3.2.2 Information from advertising ... ... Steps to delivery 62 -- 6.1 Refine CLICK and the Proposed Policy Prerequisites 62 -- 6.2 Pile« in select ...
xi, 69 stran : ilustrace
- MeSH
- Exercise MeSH
- Child MeSH
- Information Technology MeSH
- Adolescent MeSH
- Noncommunicable Diseases MeSH
- Pediatric Obesity MeSH
- Alcohol Drinking MeSH
- Food MeSH
- Child, Preschool MeSH
- Direct-to-Consumer Advertising MeSH
- Nicotiana MeSH
- Check Tag
- Child MeSH
- Adolescent MeSH
- Child, Preschool MeSH
- Conspectus
- Veřejné zdraví a hygiena
- NML Fields
- veřejné zdravotnictví
- NML Publication type
- publikace WHO
The transient isotachophoretic stacking and sweeping was used for the on-line large-volume sample pre-concentration of bacteria, Escherichia coli and Staphylococcus aureus cells (methicillin-susceptible or methicillin-resistant), in the initial stage of micellar electrokinetic chromatography using a non-ionogenic surfactant or of capillary electrophoresis, respectively. These procedures were employed in single-piece fused silica capillary etched with supercritical water with two different internal diameter segments featuring different inner surface roughness. Large volumes (maximum 2.8 μL) of the high conductivity sample matrices, physiological saline solution, urine or blood (with purification step), spiked with examined cells were injected into the wider end of a capillary with an inlet inner diameter 195 μm. This novel on-line combination of preconcentration strategies for cells produced an up to 680-fold increase in sensitivity for E. coli or S. aureus cells. The average calculated resolutions, R, for five selected methicillin-susceptible or methicillin-resistant strains were found to be 6.3 for the agar-cultivated and 14.9 for the blood-incubated cells. A low number of bacteria similar to those in clinical samples were also tested. The modified surface roughness step helped to significantly narrow the cell zones and to increase resolution. The migration velocities of E. coli agar-cultivated and blood-incubated cells were approximately the same as those of S. aureus, probably due to the minimal differences in their surface properties. This procedure, on-line pre-concentration and separation of bacteria, is rapid and provides good reproducibility and repeatability.
- MeSH
- Chromatography, Micellar Electrokinetic Capillary methods MeSH
- Electrophoresis, Capillary methods MeSH
- Escherichia coli isolation & purification MeSH
- Escherichia coli Infections microbiology MeSH
- Humans MeSH
- Micelles MeSH
- Silicon Dioxide chemistry MeSH
- Surface-Active Agents chemistry MeSH
- Surface Properties MeSH
- Staphylococcal Infections microbiology MeSH
- Staphylococcus aureus isolation & purification MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Meiotic chromosome segregation is critical for fertility across eukaryotes, and core meiotic processes are well conserved even between kingdoms. Nevertheless, recent work in animals has shown that at least some meiosis genes are highly diverse or strongly differentiated among populations. What drives this remains largely unknown. We previously showed that autotetraploid Arabidopsis arenosa evolved stable meiosis, likely through reduced crossover rates, and that associated with this there is strong evidence for selection in a subset of meiosis genes known to affect axis formation, synapsis, and crossover frequency. Here, we use genome-wide data to study the molecular evolution of 70 meiosis genes in a much wider sample of A. arenosa. We sample the polyploid lineage, a diploid lineage from the Carpathian Mountains, and a more distantly related diploid lineage from the adjacent, but biogeographically distinct Pannonian Basin. We find that not only did selection act on meiosis genes in the polyploid lineage but also independently on a smaller subset of meiosis genes in Pannonian diploids. Functionally related genes are targeted by selection in these distinct contexts, and in two cases, independent sweeps occurred in the same loci. The tetraploid lineage has sustained selection on more genes, has more amino acid changes in each, and these more often affect conserved or potentially functional sites. We hypothesize that Pannonian diploid and tetraploid A. arenosa experienced selection on structural proteins that mediate sister chromatid cohesion, the formation of meiotic chromosome axes, and synapsis, likely for different underlying reasons.
Speciation is a continuous process during which genetic changes gradually accumulate in the genomes of diverging species. Recent studies have documented highly heterogeneous differentiation landscapes, with distinct regions of elevated differentiation ("differentiation islands") widespread across genomes. However, it remains unclear which processes drive the evolution of differentiation islands; how the differentiation landscape evolves as speciation advances; and ultimately, how differentiation islands are related to speciation. Here, we addressed these questions based on population genetic analyses of 200 resequenced genomes from 10 populations of four Ficedula flycatcher sister species. We show that a heterogeneous differentiation landscape starts emerging among populations within species, and differentiation islands evolve recurrently in the very same genomic regions among independent lineages. Contrary to expectations from models that interpret differentiation islands as genomic regions involved in reproductive isolation that are shielded from gene flow, patterns of sequence divergence (d(xy) and relative node depth) do not support a major role of gene flow in the evolution of the differentiation landscape in these species. Instead, as predicted by models of linked selection, genome-wide variation in diversity and differentiation can be explained by variation in recombination rate and the density of targets for selection. We thus conclude that the heterogeneous landscape of differentiation in Ficedula flycatchers evolves mainly as the result of background selection and selective sweeps in genomic regions of low recombination. Our results emphasize the necessity of incorporating linked selection as a null model to identify genome regions involved in adaptation and speciation.
- MeSH
- Species Specificity MeSH
- Genome MeSH
- Genomics MeSH
- Genotyping Techniques MeSH
- Polymorphism, Single Nucleotide MeSH
- Passeriformes classification genetics MeSH
- Genetics, Population MeSH
- Recombination, Genetic * MeSH
- Reproductive Isolation MeSH
- Sequence Analysis, DNA MeSH
- Selection, Genetic * MeSH
- Gene Flow MeSH
- Genetic Speciation * MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
... Recording of Muscle and -- Nerve Potentials 77 Surface and Needle Electrodes 77 Sweep Speed and Amplification ... ... Quantitative Measurements 342 Methods of Assessment 342 Selection and Analysis 342 Automated Methods ... ... xxiv • Contents -- Limb Nerves, Plexus, and Roots 577 Tethered Cord 578 Pedicle Screw Placement 580 Selective ...
4th ed. xxix, 1146 s. : il., tab. ; 26 cm + 1 CD-ROM
- MeSH
- Electrodiagnosis methods MeSH
- Electromyography MeSH
- Spinal Cord Diseases diagnosis MeSH
- Neural Conduction physiology MeSH
- Synaptic Transmission physiology MeSH
- Neuromuscular Diseases diagnosis MeSH
- Conspectus
- Patologie. Klinická medicína
- NML Fields
- neurologie
- diagnostika
- NML Publication type
- kolektivní monografie
Taxa of microbial eukaryotes defined on morphological basis display a large degree of genetic diversity, implying the existence of numerous cryptic species. However, it has been postulated that genetic diversity merely mirrors accumulation of neutral mutations. As a case taxon to study cryptic diversity in protists, we used a widely distributed filamentous genus, Klebsormidium, specifically the lineage E (K. flaccidum/K. nitens complex) containing a number of morphologically similar strains. Fourteen clades were recognized in the phylogenetic analysis based on a concatenated ITS rDNA + rbcL data set of more than 70 strains. The results of inferred character evolution indicated the existence of phylogenetic signal in at least two phenotypic characters (production of hydro-repellent filaments and morphology of zoosporangia). Moreover, the lineages recovered exhibited strong ecological preferences to one of the three habitat types: natural subaerial substrata, artificial subaerial substrata, and aquatic habitats. We interpret these results as evidence of existence of a high number of cryptic species within the single morphospecies. We consider that the permanent existence of genetically and ecologically well-defined cryptic species is enabled by the mechanism of selective sweep.
