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131.
Josef F Dax Gernot R Müller-Putz Klaus Pfurtscheller Berndt Urlesberger Wilhelm Müller Gert Pfurtscheller 《Biomedizinische Technik》2005,50(1-2):19-24
Recordings of the electroencephalogram (EEG) and of the heart rate variability (HRV) of preterm neonates can give important information on the actual state of the nervous system. Both signals, EEG and HRV, are affected by parameters such as gestational age, stage of maturation and behavioral state. This work describes a method for automatic detection of slow wave EEG-bursts and a tool to average changes in the EEG and the corresponding heart rate. The detection is based on the hjorth activity (HA), calculated from the EEG. HA spikes (HAS) are identified by the determination of the beginning and end of existing spikes. HAS maxima and the time between two consecutive HAS are the basis for the triggering of the bursts. EEG power and time synchronized HR changes are averaged with a time window length of 20 s. Resultant, HR increase and duration are determined. These parameters, obtained by the automatic detection, proved to be comparable to the results of an expert. 相似文献
132.
The chromatin modifying complex CoREST/LSD1 negatively regulates notch pathway during cerebral cortex development
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Cecilia I. Lopez Katherine E. Saud Rodrigo Aguilar F. Andrés Berndt José Cánovas Martín Montecino Manuel Kukuljan 《Developmental neurobiology》2016,76(12):1360-1373
The development of the cerebral cortex is a dynamic and coordinated process in which cell division, cell death, migration, and differentiation must be highly regulated to acquire the final architecture and functional competence of the mature organ. Notch pathway is an important regulator of differentiation and it is essential to maintain neural stem cell (NSC) pool. Here, we studied the role of epigenetic modulators such as lysine‐specific demethylase 1 (LSD1) and its interactor CoREST in the regulation of the Notch pathway activity during the development of the cerebral cortex. We found that CoREST and LSD1 interact in vitro with RBPJ‐κ in the repressor complex and these proteins are released upon overexpression of Notch intracellular domain (NICD). We corroborated LSD1 and RBPJ‐κ interaction in developing cerebral cortex and also found that LSD1 binds to the hes1 promoter. Knock‐down of CoREST and LSD1 by in utero electroporation increases Hes1 expression in vivo and decreases Ngn2. Interestingly, we found a functional interaction between CoREST and LSD1 with Notch pathway. This conclusion is based on the observation that both the defects in neuronal migration and the increase in the number of cells expressing Sox2 and Tbr2 were associated to the knock‐down of either CoREST or LSD1 and were reversed by the loss of Notch. These results demonstrate that CoREST and LSD1 downregulate the Notch pathway in the developing cerebral cortex, thus suggesting a role of epigenetic regulation in the fine tuning of cell differentiation. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1360–1373, 2016 相似文献
133.
Erik S. Mittra Norman Koglin Camila Mosci Meena Kumar Aileen Hoehne Khun Visith Keu Andrei H. Iagaru Andre Mueller Mathias Berndt Santiago Bullich Matthias Friebe Heribert Schmitt-Willich Volker Gekeler Lüder M. Fels Claudia Bacher-Stier Dae Hyuk Moon Frederick T. Chin Andrew W. Stephens Ludger M. Dinkelborg Sanjiv S. Gambhir 《PloS one》2016,11(2)
Purpose
(S)-4-(3-[18F]Fluoropropyl)-L-glutamic acid (18F-FSPG) is a novel radiopharmaceutical for Positron Emission Tomography (PET) imaging. It is a glutamate analogue that can be used to measure xC- transporter activity. This study was performed to assess the feasibility of 18F-FSPG for imaging orthotopic brain tumors in small animals and the translation of this approach in human subjects with intracranial malignancies.Experimental Design
For the small animal study, GS9L glioblastoma cells were implanted into brains of Fischer rats and studied with 18F-FSPG, the 18F-labeled glucose derivative 18F-FDG and with the 18F-labeled amino acid derivative 18F-FET. For the human study, five subjects with either primary or metastatic brain cancer were recruited (mean age 50.4 years). After injection of 300 MBq of 18F-FSPG, 3 whole-body PET/Computed Tomography (CT) scans were obtained and safety parameters were measured. The three subjects with brain metastases also had an 18F-FDG PET/CT scan. Quantitative and qualitative comparison of the scans was performed to assess kinetics, biodistribution, and relative efficacy of the tracers.Results
In the small animals, the orthotopic brain tumors were visualized well with 18F-FSPG. The high tumor uptake of 18F-FSPG in the GS9L model and the absence of background signal led to good tumor visualization with high contrast (tumor/brain ratio: 32.7). 18F-FDG and 18F-FET showed T/B ratios of 1.7 and 2.8, respectively. In the human pilot study, 18F-FSPG was well tolerated and there was similar distribution in all patients. All malignant lesions were positive with 18F-FSPG except for one low-grade primary brain tumor. In the 18F-FSPG-PET-positive tumors a similar T/B ratio was observed as in the animal model.Conclusions
18F-FSPG is a novel PET radiopharmaceutical that demonstrates good uptake in both small animal and human studies of intracranial malignancies. Future studies on larger numbers of subjects and a wider array of brain tumors are planned.Trial Registration
ClinicalTrials.gov NCT01186601相似文献134.
Heparin-induced thrombocytopenia 总被引:2,自引:0,他引:2
Thrombocytopenia is a frequent and sometimes insidious complication of anticoagulant therapy with heparin. Two types of heparin-induced thrombocytopenia with a distinct aetiology have been recognized. Type I is characterized by a mild thrombocytopenia of early onset which requires careful monitoring but usually not the cessation of heparin therapy. The mild thrombocytopenia is probably due to the mild pro-aggregatory properties of heparin and can be more severe in the presence of other predisposing factors, e.g. sepsis. Type II heparin-induced thrombocytopenia is more severe and usually occurs after a period of 7-10 days. Heparin therapy should be ceased immediately and other anticoagulant therapy initiated. The thrombocytopenia is believed to be due to the development of a heparin-dependent antibody that causes platelet aggregation and release. The precise mechanism of heparin-dependent antibody-platelet interaction is still not entirely clear but probably involves the binding of an antibody-heparin immune complex to the platelet Fc receptor. 相似文献
135.
With the aim of elucidating mechanisms behind bacteria-induced deleterious effects and differential cultivar responses to bacterial inoculations, wheat seedlings were subjected to various tests under gnotobiotic conditions. Inoculation with two deleterious Pseudomonas isolates, Å 112 (fluorescent) and Å 313 (nonfluorescent), induced leaf symptoms and shoot and root growth inhibition, while inoculation with growthneutral bacteria (Serratia liquefaciens andEscherichia coli) had no such effects. Deleterious effects were induced at low inoculum densities (<103 cells per plant), but required addition of nutrient broth in small amounts for consistency. Effects similar to those obtained with living inoculum could be induced by treating plants with sterile culture filtrates from isolate Å 313 or volatile bacterial metabolites from isolate Å 112. Wheat cultivars previously found to differ in their reaction to inoculation under non-sterile conditions, responded differentially to Å 112 and Å 313 also in the gnotobiotic assay. The results agree with the hypothesis that neither cultivar reaction nor the bacterial effects as such are mediated by interactions with an indigenous rhizosphere microflora. 相似文献
136.
137.
Rudolf Berndt und Wolfgang Winkel 《Journal of Ornithology》1972,113(4):357-365
Zusammenfassung 1. Der Auswertung liegen über 600 Kontrollergebnisse zugrunde, die an 81 Bruten vonParus major, 23 vonP. caeruleus, 21 vonP. ater, 5 vonP. cristatus und 2 vonP. palustris in Untersuchungsgebieten bei Braunschweig im Jahr 1971 gewonnen wurden.2. Kohlmeisen- schlafen zuweilen bis zum Ausfliegen der Jungen nachts in der Nisthöhle.3. Der Übergang zwischen dem Schlafen in der Höhle und außerhalb derselben setzt bei Blaumeisen- gesichert früher ein als bei Kohlmeisen-. Während letztere bei einem Alter der Nestlinge von 13 Tagen noch stets bei den Jungen schliefen, nächtigte zu diesem Zeitpunkt bei der Blaumeise bereits die Hälfte der außerhalb der Nisthöhle.4. Tannen-, Hauben- und Nonnenmeisen verhalten sich hinsichtlich des Nächtigens während der Zeit der Jugendaufzucht ähnlich wie Blaumeisen.5. Ein Austausch verschieden alter Bruten gegeneinander (Versuche mit Kohl- und Blaumeisen) hatte keinen größeren Einfluß auf das Schlafverhalten der . Die Anzahl der Nächte, die die nach dem Schlüpfen der Jungen noch in der Höhle übernachteten, war somit bei Meisen im Gegensatz zum TrauerschnäpperFicedula hypoleuca (Winkel &Berndt 1972) weitgehend unabhängig von exogenen Reizen, die von Nestlingen ausgehen. Es wird daher vermutet, daß bei Meisen die Periodenlänge des Bruthöhlenschlafens erblich fixiert ist. Hierfür sprechen auch die Beziehungen, die zwischen letzterem und dem Einsetzen des Abwehrzischens der Nestjungen zu bestehen scheinen, was im einzelnen diskutiert wird.
Erweiterte Fassung eines von W.Winkel am 15, 10, 1972 auf der 84. Jahresversammlung der Deutschen Ornithologen-Gesellschaft in Saarbrücken gehaltenen Vortrages. 相似文献
On nocturnal brooding by female tits(Parus) while rearing young
Summary 1. This evaluation is based upon 600 research results from 81 broods ofParus major, 23 ofP. caeruleus, 21 ofP. ater, 5 ofParus cristatus, and 2 ofP. palustris in study areas near Braunschweig in the year 1971.2. Great Tit females slept in the breeding nest box during the night, occasionally even right up to the time of fledging of the young (fig., table 1).3. With female Blue Tits, the transition between sleeping inside the nest box and out of it began earlier (statistically significant) than with Great Tit females. While the latter continued regularly to sleep with the young when the nestlings were 13 days old, half of the female Blue Tits under observation spent the night outside the nest box at this stage (fig., table 1).4. Coal Tits, Crested Tits and Marsh Tits behave in the same way as Blue Tits in respect of their sleeping habits during the rearing of young (table 1).5. An interchange of broods of different age had no obvious effect on the sleeping habits of the females (tests with Great and Blue Tits) (table 2 and 3). The number of nights spent by the female tits in the nest box after the young hatched, unlike the equivalent behaviour in Pied FlycatchersFicedula hypoleuca (Winkel &Berndt 1972), was largely independent of exogenous releasers from the nestlings. It is presumed that in Tits, the duration of the period of sleeping in the nest box is genetically fixed. This is also suggested by the apparent connection between sleeping-in and the onset of the defensive hiss display of the nestlings. This is discussed in detail.
Erweiterte Fassung eines von W.Winkel am 15, 10, 1972 auf der 84. Jahresversammlung der Deutschen Ornithologen-Gesellschaft in Saarbrücken gehaltenen Vortrages. 相似文献
138.
139.
Human alveolar macrophage fibronectin: synthesis, secretion, and ultrastructural localization during gelatin-coated latex particle binding 总被引:14,自引:4,他引:10
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Human pulmonary alveolar macrophages synthesized and secreted several characteristic high molecular weight proteins for at least 7 d in vitro. Immunoprecipitates of medium and cell lysates from metabolically labeled cultures with specific anti-human plasma fibronectin IgG contained one major labeled polypeptide of molecular weight 440,000 (unreduced) or 220,000 (reduced). An identical polypeptide in conditioned medium from radiolabeled macrophages bound specifically to gelatin-Sepharose, demonstrating that alveolar macrophages synthesized and secreted a molecule immunologically and functionally similar to fibronectin. Fibronectin was the major newly synthesized and secreted polypeptide of freshly harvested alveolar macrophages. Pulse-chase experiments revealed that newly synthesized fibronectin was rapidly secreted into medium, approximately 50 percent appearing by 1 h and 80 percent by 8 h. Immunoperoxidase staining using antifibronectin F(ab’)(2)-peroxidase conjugates revealed the majority of immunoreactive fibronectin to be intracellular, localized to endoplasmic reticulum and Golgi apparatus. No extracellular matrix fibronectin was visualized, and cell surface staining was rarely seen, usually appearing only at sites where cells were closely apposed and not at sites of macrophage-substrate attachment. Similar immunostaining of fibroblast cultures revealed cell surface-associated fibrillar fibronectin. Ultrastructural localization of fibronectin during binding and phagocytosis of gelatin-coated and plain latex particles revealed fibronectin only on gelatin-latex beads and at their cell binding sites. Neigher plain latex beads nor their cell membrane binding sites stained for fibronectin. These results demonstrate that fibronectin is a major product of human alveolar macrophages, is rapidly secreted, and is localized at cell membrane binding sites for gelatin-coated particles. In view of the known binding properties of fibronectin, it may serve as an endogenous opsonic factor promoting the binding of staphylococcus, denatured collagen, fibrin, or other macromolecules to macrophages in the lower respiratory tract. 相似文献
140.
A terminology of the dispersion of birds, and of the ways in which it comes about, is proposed and explained. An examination of recoveries of ringed female Pied Flycatchers Ficedula hypoleuca show that many first breed a considerable distance from their birthplace, in contrast to the situation in the Blue Tit Parus caeruleus and Nuthatch Sitta europaea. The degree of such dispersion in these species, and presumably therefore the gene flow, is inversely correlated with the number of geographical races they contain. Results of experiments designed to investigate the types of dispersion mechanism occurring in F. hypoleuca indicate that both “dispersal” and “spacing” occur in birds of all ages, and that they are usually not oriented, but that the spacing of older birds which have not been constantly faithful to place usually leads to a previously known place. 相似文献