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991.
The study investigated stimulus evaluation time, event preparation, and motor action planning of patients with mild spastic cerebral palsy and a peer control group in the age range of 9 to 18 years. To this end, participants were carrying out a stimulus recognition task. Findings indicated an overall slowness and inaccurate reaction time performance of the patient group. An event-related potential analysis revealed that the stimulus evaluation processing, indexed by the parietal P300, was intact in the group of patients. Also event preparation and action planning, indexed by respectively the frontal late contingent negative variation and the frontal P2, were intact in the group of patients. It was concluded that patients' motor slowness reflected poor motor execution processes. 相似文献
992.
HM Den Ruijter SA Peters TJ Anderson AR Britton JM Dekker MJ Eijkemans G Engström GW Evans J de Graaf DE Grobbee B Hedblad A Hofman S Holewijn A Ikeda M Kavousi K Kitagawa A Kitamura H Koffijberg EM Lonn MW Lorenz EB Mathiesen G Nijpels S Okazaki DH O'Leary JF Polak JF Price C Robertson CM Rembold M Rosvall T Rundek JT Salonen M Sitzer CD Stehouwer JC Witteman KG Moons ML Bots 《JAMA : the journal of the American Medical Association》2012,308(8):796-803
993.
M?nk?re J Hakala RA Kovalainen M Korhonen H Herzig KH Sepp?l? JV J?rvinen K 《European journal of pharmaceutics and biopharmaceutics》2012,80(1):33-38
The treatment for many diseases can be improved by developing more efficient peptide delivery technologies, for example, biodegradable polymers. In this work, photocrosslinked poly(ester anhydride)s based on functionalized poly(ε-caprolactone) oligomers were investigated for their abilities to achieve controlled peptide delivery. The effect of oligomer hydrophobicity on erosion and peptide release from poly(ester anhydride)s was evaluated by developing a sustained subcutaneous delivery system for an antiobesity drug candidate, peptide YY3-36 (PYY3-36). Oligomer hydrophobicity was modified with alkenylsuccinic anhydrides containing a 12-carbon alkenyl chain. PYY3-36 was mixed as a solid powder with methacrylated poly(ester anhydride) precursors, and this mixture was photocrosslinked at room temperature to form an implant for subcutaneous administration in rats. The oligomer hydrophobicity controlled the polymer erosion and PYY3-36 release as the increased hydrophobicity via the alkenyl chain prolonged polymer erosion in vitro and sustained in vivo release of PYY3-36. In addition, photocrosslinked poly(ester anhydride)s increased the bioavailability of PYY3-36 by up to 20-fold in comparison with subcutaneous administration of solution, evidence of remarkably improved delivery. In conclusion, this work demonstrates the suitability of photocrosslinked poly(ester anhydride)s for use in peptide delivery. 相似文献
994.
995.
Orienting of attention to emotionally negative stimuli is accompanied by rapid heart rate (HR) deceleration, reflecting enhanced attentional and sensory processing. We studied whether similar emotional modulation of cardiac responding is observed in infants. HR and eye movements were recorded from 7-month-old infants while they observed a fearful or happy face that was flanked after 700 ms by a peripheral distractor for 2000 ms. An attentional bias for fearful faces was indicated by less frequent and longer latency saccades toward the distractors during fearful than happy trials. HR deceleration was significantly larger during fearful than happy trials on which infants did not make a distractor-directed saccade. For trials with a distractor-directed saccade, no difference between fearful and happy faces emerged. Thus, the bias to attend preferentially to fearful faces is accompanied by a concomitant increase in the cardiac orienting response. 相似文献
996.
Korhonen RJ Hernandez-Pavon JC Metsomaa J Mäki H Ilmoniemi RJ Sarvas J 《Medical & biological engineering & computing》2011,49(4):397-407
We present two techniques utilizing independent component analysis (ICA) to remove large muscle artifacts from transcranial
magnetic stimulation (TMS)-evoked EEG signals. The first one is a novel semi-automatic technique, called enhanced deflation
method (EDM). EDM is a modification of the deflation mode of the FastICA algorithm; with an enhanced independent component
search, EDM is an effective tool for removing the large, spiky muscle artifacts. The second technique, called manual method
(MaM) makes use of the symmetric mode of FastICA and the artifactual components are visually selected by the user. In order
to evaluate the success of the artifact removal methods, four different quality parameters, based on curve comparison and
frequency analysis, were studied. The dorsal premotor cortex (dPMC) and Broca’s area (BA) were stimulated with TMS. Both methods
removed the very large muscle artifacts recorded after stimulation of these brain areas. However, EDM was more stable, less
subjective, and thus also faster to use than MaM. Until now, examining lateral areas of the cortex with TMS—EEG has been restricted
because of strong muscle artifacts. The methods described here can remove those muscle artifacts, allowing one to study lateral
areas of the human brain, e.g., BA, with TMS—EEG. 相似文献
997.
Dhara Raijada Andrew D. Bond Flemming H. Larsen Claus Cornett Haiyan Qu Jukka Rantanen 《Pharmaceutical research》2013,30(1):280-289
Purpose
To understand the transformation pathways amongst anhydrate/hydrate solid forms of sodium naproxen and to highlight the importance of a polymorphic dihydrate within this context.Methods
Multi-temperature dynamic vapour sorption (DVS) analysis combined with variable-humidity X-ray powder diffraction (XRPD) to establish the transformation pathways as a function of temperature and humidity. XRPD and thermogravimetric analysis (TGA) to characterise bulk samples. Monitoring of in-situ dehydration using solid-state 13C CP/MAS spectroscopy.Results
At 25°C, anhydrous sodium naproxen (AH) transforms directly to one dihydrate polymorph (DH-II). At 50°C, AH transforms stepwise to a monohydrate (MH) then to the other dihydrate polymorph (DH-I). DH-II transforms to a tetrahydrate (TH) more readily than DH-I transforms to TH. Both dihydrate polymorphs transform to the same MH.Conclusions
The properties of the polymorphic dihydrate control the transformation pathways of sodium naproxen. 相似文献998.
Prapapan Pimkaew Jenni Küblbeck Aleksanteri Petsalo Jouni Jukka Apichart Suksamrarn Risto Juvonen Seppo Auriola Pawinee Piyachaturawat Paavo Honkakoski 《Toxicology in vitro》2013,27(6):2005-2012
Misclassification of Curcuma species (family Zingiberaceae) may lead to unwanted human exposure to Curcuma elata sesquiterpenes zederone and germacrone which have caused hepatotoxicity and changes in CYP expression in laboratory animals. We investigated how these compounds interact with the human cytochrome P450 (CYP) system, in order to evaluate their potential for human liver toxicity and herb–drug interactions. We found that both sesquiterpenes (1–30 μM) greatly induced expression of CYP2B6 and CYP3A4 but not CYP1A2 mRNAs in human primary hepatocytes (HPHs). This induction profile correlated with activation of constitutive androstane and pregnane X receptors. Cytotoxicity was also observed in exposed HPHs. CYP inhibition studies with pooled human liver microsomes (HLMs) indicated that zederone and germacrone moderately inhibited CYP2B6 and CYP3A4 activities in vitro, with IC50 values below 10 μM. When zederone was incubated with HLMs and NADPH, one di-epoxide metabolite was formed and by using glutathione trapping, five epoxide-derived conjugates were detected. Germacrone produced two oxidized metabolites and four glutathione conjugates. The results suggest that enzymes in HLMs convert sesquiterpenes into reactive, electrophilic compounds which may be causative for the reported liver injuries. These findings provide insight on the safety and drug–herb interactions of the Curcuma species. 相似文献
999.
Jukka Sallinen Johanna Holappa Ari Koivisto Katja Kuokkanen Hugh Chapman Jyrki Lehtimäki Petteri Piepponen Jelena Mijatovic Heikki Tanila Raimo Virtanen Jouni Sirviö Antti Haapalinna 《Basic & clinical pharmacology & toxicology》2013,113(4):239-249
The α2‐adrenoceptors (ARs) are important modulators of a wide array of physiological responses. As only a few selective compounds for the three α2‐AR subtypes (α2A, α2B and α2C) have been available, the pharmacological profile of a new α2C‐selective AR antagonist ORM‐10921 is reported. Standard in vitro receptor assays and antagonism of α2, and α1‐AR agonist ‐evoked responses in vivo were used to demonstrate the α2C‐AR selectivity for ORM‐10921 which was tested in established behavioural models related to schizophrenia and cognitive dysfunction with an emphasis on pharmacologically induced hypoglutamatergic state by phencyclidine or MK‐801. The Kb values of in vitro α2C‐ AR antagonism for ORM‐10921 varied between 0.078–1.2 nM depending on the applied method. The selectivity ratios compared to α2A‐AR subtype and other relevant receptors were 10‐100 times in vitro. The in vivo experiments supported its potent α2C‐antagonism combined with only a weak α2A‐antagonism. In the pharmacodynamic microdialysis study, ORM‐10921 was found to increase extracellular dopamine levels in prefrontal cortex in the baseline conditions. In the behavioural tests, ORM‐10921 displayed potent antidepressant and antipsychotic‐like effects in the forced swimming test and prepulse‐inhibition models analogously with the previously reported results with structurally different α2C‐selective AR antagonist JP‐1302. Our new results also indicate that ORM‐10921 alleviated the NMDA‐antagonist‐induced impairments in social behaviour and watermaze navigation. This study extends and further validates the concept that α2C‐AR is a potential therapeutic target in CNS disorders such as schizophrenia or Alzheimer's disease and suggests the potential of α2C‐antagonism to treat such disorders . 相似文献
1000.
Norman Chieng Hjalte Trnka Johan Boetker Michael Pikal Jukka Rantanen Holger Grohganz 《International journal of pharmaceutics》2013
The purpose of this study is to investigate the use of multivariate data analysis for powder X-ray diffraction-pair-wise distribution function (PXRD-PDF) data to detect phase separation in freeze-dried binary amorphous systems. Polymer–polymer and polymer–sugar binary systems at various ratios were freeze-dried. All samples were analyzed by PXRD, transformed to PDF and analyzed by principal component analysis (PCA). These results were validated by differential scanning calorimetry (DSC) through characterization of glass transition of the maximally freeze-concentrate solute (Tg’). Analysis of PXRD-PDF data using PCA provides a more clear ‘miscible’ or ‘phase separated’ interpretation through the distribution pattern of samples on a score plot presentation compared to residual plot method. In a phase separated system, samples were found to be evenly distributed around the theoretical PDF profile. For systems that were miscible, a clear deviation of samples away from the theoretical PDF profile was observed. Moreover, PCA analysis allows simultaneous analysis of replicate samples. Comparatively, the phase behavior analysis from PXRD-PDF-PCA method was in agreement with the DSC results. Overall, the combined PXRD-PDF-PCA approach improves the clarity of the PXRD-PDF results and can be used as an alternative explorative data analytical tool in detecting phase separation in freeze-dried binary amorphous systems. 相似文献