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41.
Lukas Frase Peter Selhausen Lukas Krone Sulamith Tsodor Friederike Jahn Bernd Feige Jonathan G. Maier Florian Mainberger Hannah Piosczyk Marion Kuhn Stefan Klöppel Annette Sterr Chiara Baglioni Kai Spiegelhalder Dieter Riemann Michael A. Nitsche Christoph Nissen 《Brain stimulation》2019,12(3):674-683
Background
Arousal and sleep represent basic domains of behavior, and alterations are of high clinical importance.Objective/hypothesis
The aim of this study was to further elucidate the neurobiology of insomnia disorder (ID) and the potential for new treatment developments, based on the modulation of cortical activity through the non-invasive brain stimulation technique transcranial direct current stimulation (tDCS). Specifically, we tested the hypotheses that bi-frontal anodal tDCS shortens and cathodal tDCS prolongs total sleep time in patients with ID, compared to sham stimulation. Furthermore, we tested for differences in indices of arousal between ID patients and healthy controls and explored their potential impact on tDCS effects.Methods
Nineteen ID patients underwent a within-subject repeated-measures sleep laboratory study with adaptation, baseline and three experimental nights. Bifrontal anodal, cathodal and sham tDCS was delivered in a counterbalanced order immediately prior to sleep. Wake EEG was recorded prior to and after tDCS as well as on the following morning. Subsequently, we compared patients with ID to a healthy control group from an earlier dataset.Results
Against our hypothesis, we did not observe any tDCS effects on sleep continuity or sleep architecture in patients with ID. Further analyses of nights without stimulation demonstrated significantly increased levels of arousal in ID patients compared to healthy controls, as indexed by subjective reports, reduced total sleep time, increased wake after sleep onset and increased high frequency EEG power during wakefulness and NREM sleep. Of note, indices of increased arousal predicted the lack of effect of tDCS in ID patients.Conclusions
Our study characterizes for the first time differential effects of tDCS on sleep in patients with ID and healthy controls, presumably related to persistent hyperarousal in ID. These findings suggest that adapted tDCS protocols need to be developed to modulate arousal and sleep dependent on baseline arousal levels. 相似文献42.
43.
Lucht A Formenty P Feldmann H Gotz M Leroy E Bataboukila P Grolla A Feldmann F Wittmann T Campbell P Atsangandoko C Boumandoki P Finke EJ Miethe P Becker S Grunow R 《The Journal of infectious diseases》2007,196(Z2):S184-S192
Ebola virus (EBOV) has caused outbreaks of severe viral hemorrhagic fever in regions of Central Africa where medical facilities are ill equipped and diagnostic capabilities are limited. To obtain a reliable test that can be implemented easily under these conditions, monoclonal antibodies to the EBOV matrix protein (VP40), which previously had been found to work in a conventional enzyme-linked immunosorbent assay, were used to develop an immunofiltration assay for the detection of EBOV antigen in chemically inactivated clinical specimens. The assay was evaluated by use of defined virus stocks and specimens from experimentally infected animals. Its field application was tested during an outbreak of Ebola hemorrhagic fever in 2003. Although the original goal was to develop an assay that would detect all EBOV species, only the Zaire and Sudan species were detected in practice. The assay represents a first-generation rapid field test for the detection of EBOV antigen that can be performed in 30 min without electrical power or expensive or sensitive equipment. 相似文献
44.
High diversity of ankA sequences of Anaplasma phagocytophilum among Ixodes ricinus ticks in Germany 下载免费PDF全文
von Loewenich FD Baumgarten BU Schröppel K Geissdörfer W Röllinghoff M Bogdan C 《Journal of clinical microbiology》2003,41(11):5033-5040
In Germany humans with acute granulocytic ehrlichiosis have not yet been described. Here, we characterized three different genes of Anaplasma phagocytophilum strains infecting German Ixodes ricinus ticks in order to test whether they differ from strains in other European countries and the United States. A total of 1,022 I. ricinus ticks were investigated for infection with A. phagocytophilum by nested PCR and sequence analysis. Forty-two (4.1%) ticks were infected. For all positive ticks, parts of the 16S rRNA and groESL genes were sequenced. The complete coding sequence of the ankA gene could be determined in 24 samples. The 16S rRNA and groESL gene sequences were as much as 100% identical to known sequences. Fifteen ankA sequences were >/=99.37% identical to sequences derived from humans with granulocytic ehrlichiosis in Europe and from a horse with granulocytic ehrlichiosis in Germany. Thus, German I. ricinus ticks most likely harbor A. phagocytophilum strains that can cause disease in humans. Nine additional sequences were clearly different from known ankA sequences. Because these newly described sequences have never been obtained from diseased humans or animals, their biological significance is currently unknown. Based on this unexpected sequence heterogeneity, we propose to use the ankA gene for further phylogenetic analyses of A. phagocytophilum and to investigate the biology and pathogenicity of strains that differ in the ankA gene. 相似文献
45.
Karch R Neumann F Neumann M Szawlowski P Schreiner W 《Annals of biomedical engineering》2003,31(5):548-563
Topological and metric properties of Voronoi polyhedra (VP) generated by the distal end points of terminal segments in arterial tree models grown by the method of constrained constructive optimization (CCO) are analyzed with the aim to characterize the spatial distribution of their supply sites relative to randomly distributed points as a reference model. The distributions of the number N
f
of Voronoi cell faces, cell volume V, surface area S, area A of individual cell faces, and asphericity parameter of the CCO models are all significantly different from the ones of random points, whereas the distributions of V, S, and are also significantly different among CCO models optimized for minimum intravascular volume and minimum segment length (p < 0.0001). The distributions of N
f
, V, and S of the CCO models are reasonably well approximated by two-parameter gamma distributions. We study scaling of intravascular blood volume and arterial cross-sectional area with the volume of supplied tissue, the latter being represented by the VP of the respective terminal segments. We observe scaling exponents from 1.20 ± 0.007 to 1.08 ± 0.005 for intravascular blood volume and 0.77 ± 0.01 for arterial cross-sectional area. Setting terminal flows proportional to the associated VP volumes during tree construction yields a relative dispersion of terminal flows of 37% and a coefficient of skewness of 1.12. © 2003 Biomedical Engineering Society.
PAC2003: 8719Uv, 8710+e, 4720Ky, 0260Pn, 0230Oz 相似文献
46.
Ettelt S Grabe HJ Ruhrmann S Buhtz F Hochrein A Kraft S Pukrop R Klosterkötter J Falkai P Maier W John U Freyberger HJ Wagner M 《Journal of affective disorders》2008,107(1-3):265-269
INTRODUCTION: This study investigates the role of harm avoidance (HA) as a possible risk factor in the familiality of obsessive-compulsive disorder (OCD). HA is considered to be a genetically influenced personality trait with an increasingly understood neuroanatomical basis. METHOD: 75 subjects with OCD from hospital sites and a community sample and their 152 first degree relatives and 75 age and sex matched controls with their 143 first degree relatives were evaluated with structured clinical interviews (DSM-IV). HA was assessed with Cloninger's Tridimensional Personality Questionnaire (TPQ). RESULTS: Subjects with OCD had higher scores of HA than controls (p相似文献
47.
Maria I. Georgi Julia Rosendahl Franziska Ernst Dorothee Günzel Jörg R. Aschenbach Holger Martens Friederike Stumpff 《Pflügers Archiv : European journal of physiology》2014,466(9):1689-1712
It has long been established that the absorption of short-chain fatty acids (SCFA) across epithelia stimulates sodium proton exchange. The apically released protons are not available as countercations for the basolateral efflux of SCFA anions and a suitable transport model is lacking. Patch clamp and microelectrode techniques were used to characterize an anion conductance expressed by cultured cells of the sheep and bovine rumen and the sheep omasum and to localize the conductance in the intact tissue. Cells were filled with a Na-gluconate solution and superfused with sodium salts of acetate, propionate, butyrate, or lactate. Reversal potential rose and whole cell current at +100 mV decreased with the size of the anion. Anion-induced currents could be blocked by diisothiocyanato-stilbene-2,2′-disulfonic acid (DIDS), NPPB (200?μmol l?1), or pCMB (1 mmol l?1). In patches of bovine ruminal cells, single channels were observed with a conductance for chloride (327?±?11 pS), acetate (115?±?8 pS), propionate (102?±?10 pS), butyrate (81?±?2 pS), and gluconate (44?±?3 pS). Channels expressed by sheep rumen and omasum were similar. Microelectrode experiments suggest basolateral localization. In conclusion, forestomach epithelia express basolateral maxi-anion channels with a permeability sequence of chloride?>?acetate?>?propionate?>?butyrate. SCFA absorption may resemble functionally coupled transport of NaCl, with the Na+/K+-ATPase driving the basolateral efflux of the anion through a channel. Since protons are apically extruded, the model accurately predicts that influx of buffers with saliva is essential for the pH homeostasis of the ruminant forestomach. 相似文献
48.
Bodo B. Beck Jennifer B. Phillips Malte P. Bartram Jeremy Wegner Michaela Thoenes Andrea Pannes Josephina Sampson Raoul Heller Heike Göbel Friederike Koerber Antje Neugebauer Andrea Hedergott Gudrun Nürnberg Peter Nürnberg Holger Thiele Janine Altmüller Mohammad R. Toliat Simon Staubach Kym M. Boycott Enza Maria Valente Andreas R. Janecke Tobias Eisenberger Carsten Bergmann Lars Tebbe Yang Wang Yundong Wu Andrew M. Fry Monte Westerfield Uwe Wolfrum Hanno J. Bolz 《Human mutation》2014,35(10):1153-1162
We describe a consanguineous Iraqi family with Leber congenital amaurosis (LCA), Joubert syndrome (JBTS), and polycystic kidney disease (PKD). Targeted next‐generation sequencing for excluding mutations in known LCA and JBTS genes, homozygosity mapping, and whole‐exome sequencing identified a homozygous missense variant, c.317G>C (p.Arg106Pro), in POC1B, a gene essential for ciliogenesis, basal body, and centrosome integrity. In silico modeling suggested a requirement of p.Arg106 for the formation of the third WD40 repeat and a protein interaction interface. In human and mouse retina, POC1B localized to the basal body and centriole adjacent to the connecting cilium of photoreceptors and in synapses of the outer plexiform layer. Knockdown of Poc1b in zebrafish caused cystic kidneys and retinal degeneration with shortened and reduced photoreceptor connecting cilia, compatible with the human syndromic ciliopathy. A recent study describes homozygosity for p.Arg106ProPOC1B in a family with nonsyndromic cone‐rod dystrophy. The phenotype associated with homozygous p.Arg106ProPOC1B may thus be highly variable, analogous to homozygous p.Leu710Ser in WDR19 causing either isolated retinitis pigmentosa or Jeune syndrome. Our study indicates that POC1B is required for retinal integrity, and we propose POC1B mutations as a probable cause for JBTS with severe PKD. 相似文献
49.
Gertraut Altreuther Annette Schimmel Iris Schroeder Thomas Bach Samuel Charles Dawid J. Kok Friederike Kraemer Sonja Wolken David Young Klemens J. Krieger 《Parasitology research》2009,105(Z1):1-8
The efficacy of emodepside plus praziquantel tablets (Profender? tablets for dogs) against mature adult, immature adult and
larval stages of Toxocara canis and Toxascaris leonina was evaluated in ten randomised, blinded and placebo-controlled dose confirmation studies in naturally or experimentally
infected dogs. The tablets were used at the proposed minimum dose of 1 mg emodepside and 5 mg praziquantel per kg body weight.
Efficacy was calculated based on worm counts after necropsy. Five studies demonstrated >99% efficacy against mature adult,
>92% efficacy against immature adult, >98% efficacy against L4 and >94% efficacy against L3 larval stages of T. canis. Another five studies demonstrated >99% efficacy against mature and immature adult and >95% efficacy against L4 larval stages
of T. leonina. No side effects of the treatment were observed. Emodepside plus praziquantel tablets thus provide a comprehensive new treatment
option for ascarid infections in the dog. 相似文献
50.