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11.
Marta Anna Lech Monika Lekiewicz Kinga Kamiska Zofia Rog Elbieta Lorenc-Koci 《International journal of molecular sciences》2021,22(12)
Growing body of evidence points to dysregulation of redox status in the brain as an important factor in the pathogenesis of schizophrenia. The aim of our study was to evaluate the effects of l-buthionine-(S,R)-sulfoximine (BSO), a glutathione (GSH) synthesis inhibitor, and 1-[2-Bis(4-fluorophenyl)methoxy]ethyl]-4-(3-phenylpropyl)piperazine dihydrochloride (GBR 12909), a dopamine reuptake inhibitor, given alone or in combination, to Sprague–Dawley pups during early postnatal development (p5–p16), on the time course of the onset of schizophrenia-like behaviors, and on the expression of brain-derived neurotrophic factor (BDNF) mRNA and its protein in the prefrontal cortex (PFC) and hippocampus (HIP) during adulthood. BSO administered alone decreased the levels of BDNF mRNA and its protein both in the PFC and HIP. Treatment with the combination of BSO + GBR 12909 also decreased BDNF mRNA and its protein in the PFC, but in the HIP, only the level of BDNF protein was decreased. Schizophrenia-like behaviors in rats were assessed at three time points of adolescence (p30, p42–p44, p60–p62) and in early adulthood (p90–p92) using the social interaction test, novel object recognition test, and open field test. Social and cognitive deficits first appeared in the middle adolescence stage and continued to occur into adulthood, both in rats treated with BSO alone or with the BSO + GBR 12909 combination. Behavior corresponding to positive symptoms in humans occurred in the middle adolescence period, only in rats treated with BSO + GBR 12909. Only in the latter group, amphetamine exacerbated the existing positive symptoms in adulthood. Our data show that rats receiving the BSO + GBR 12909 combination in the early postnatal life reproduced virtually all symptoms observed in patients with schizophrenia and, therefore, can be considered a valuable neurodevelopmental model of this disease. 相似文献
12.
Two groups of 14 right-handed female undergraduates saw a series of slides for 1 msec. Subsequently, these slides were paired with similar but novel slides. One group was asked to view the pairs analytically and to select the one they thought they had seen before. The other group was asked to view the pairs holistically and indicate which of the 2 they preferred. Results support the hypothesis that analytically instructed Ss would be more likley to engage the parietal region of their left hemisphere and holistically instructed Ss would favor relative activation of the right parietal region. An inverse relation was also detected between parietal laterality and selection accuracy. It is suggested that differential hemispheric involvement may account for the observation that affective discrimination can be performed in the absence of conscious awareness. Findings are discussed in terms of a memory model of information processing. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
Novel biodegradable form stable phase change materials were obtained in a process involving potato starch gelatinization in water/poly(ethylene oxide) (PEO) solution. DSC and microscopic investigations revealed that the presence of the starch considerably changes PEO phase transition behavior–in the blends solid–solid phase transition for PEO/starch 1 : 3 and 1 : 1 w/w has been observed; for PEO/starch blend 3 : 1 w/w solid–solid phase transition with a partial melting of PEO unbounded through hydrogen bonds with starch has been detected. The heat of phase transition depends on the strength of hydrogen bonds between PEO and starch. The intermolecular interactions were evidenced by FTIR analysis, which showed considerably shift of the stretching vibration bands of both the O? H group (proton‐donor group) from starch and PEO. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
14.
15.
The differences are analyzed in distribution and time evolution of the temperature, moisture content, and drying-induced stresses generated by convective and microwave drying. The theoretical analysis of the drying induced stresses and the deformations of dried materials is based on the elastic and viscoelastic constitutive models. The theoretical predictions are confronted with the experimental data obtained by the acoustic emission (AE) method, which enable monitoring on line the development of the drying induced stresses. The system of double coupled differential equations of the thermomechanical drying model is solved numerically using the finite element (FEM) and the finite difference (FDM) methods. A cylindrical sample made of kaolin was chosen to compare experimental data with the model solution. Essential differences were identified in the analyzed items for convective and microwave drying as well as a significant difference in stress distribution was noted for elastic and viscoelastic constitutive models. 相似文献
16.
Izabela Ratajczak Kinga Wich?acz-Szentner Bart?omiej Mazela Patrycja Hochmańska Iwona Rissmann 《Holz als Roh- und Werkstoff》2010,18(1):483-486
In this study the reactivity of cellulose with new solvent born preparations containing organosilanes, alkyd resin and natural
oil was analysed. Structural analysis of cellulose after reaction with organosilanes and after extraction was performed using
Fourier-transform infrared spectroscopy (FTIR). In IR spectra the analyzed bands included 1250 cm−1 responsible for vibrations of the SiC group and 800 cm−1 responsible for vibrations of SiC and/or SiO groups. These bands are characteristic of silicon bonds with atoms of carbon
and oxygen originating from the methoxy groups found in organosilanes. The presence of these bands in the spectra proves the
occurrence of a reaction between cellulose and organosilanes. The concentration of silicon was determined by AAS in cellulose
after reaction with preparations and after extraction. 相似文献
17.
Katarzyna Chamera Ewa Trojan Katarzyna Kotarska Magdalena Szuster-Guszczak Natalia Bryniarska Kinga Tylek Agnieszka Basta-Kaim 《International journal of molecular sciences》2021,22(4)
Multiple lines of evidence support the pathogenic role of maternal immune activation (MIA) in the occurrence of the schizophrenia-like disturbances in offspring. While in the brain the homeostatic role of neuron-microglia protein systems is well documented, the participation of the CX3CL1-CX3CR1 and CD200-CD200R dyads in the adverse impact of MIA often goes under-recognized. Therefore, in the present study, we examined the effect of MIA induced by polyinosinic:polycytidylic acid (Poly I:C) on the CX3CL1-CX3CR1 and CD200-CD200R axes, microglial trajectory (MhcII, Cd40, iNos, Il-1β, Tnf-α, Il-6, Arg1, Igf-1, Tgf-β and Il-4), and schizophrenia-like behaviour in adult male offspring of Sprague-Dawley rats. Additionally, according to the “two-hit” hypothesis of schizophrenia, we evaluated the influence of acute challenge with Poly I:C in adult prenatally MIA-exposed animals on the above parameters. In the present study, MIA evoked by Poly I:C injection in the late period of gestation led to the appearance of schizophrenia-like disturbances in adult offspring. Our results revealed the deficits manifested as a diminished number of aggressive interactions, presence of depressive-like episodes, and increase of exploratory activity, as well as a dichotomy in the sensorimotor gating in the prepulse inhibition (PPI) test expressed as two behavioural phenotypes (MIAPPI-low and MIAPPI-high). Furthermore, in the offspring rats subjected to a prenatal challenge (i.e., MIA) we noticed the lack of modulation of behavioural changes after the additional acute immune stimulus (Poly I:C) in adulthood. The important finding reported in this article is that MIA affects the expression and levels of the neuron-microglia proteins in the frontal cortex and hippocampus of adult offspring. We found that the changes in the CX3CL1-CX3CR1 axis could affect microglial trajectory, including decreased hippocampal mRNA level of MhcII and elevated cortical expression of Igf-1 in the MIAPPI-high animals and/or could cause the up-regulation of an inflammatory response (Il-6, Tnf-α, iNos) after the “second hit” in both examined brain regions and, at least in part, might differentiate behavioural disturbances in adult offspring. Consequently, the future effort to identify the biological background of these interactions in the Poly I:C-induced MIA model in Sprague-Dawley rats is desirable to unequivocally clarify this issue. 相似文献
18.
Anna?Jarczyk-J?dryka Katarzyna?Bijak Kinga?Skrzeczyna Zbigniew?GrobelnyEmail author Ewa?Schab-BalcerzakEmail author 《Polymer Bulletin》2017,74(2):325-335
A series carbazolyl-containing polymers were synthesized by anionic polymerization of various oxiranes and methyl methacrylate. The polymerization was carried out using as initiator carbazylpotassium activated 18-crown-6 in THF. The polymers were prepared and found using size exclusion chromatography to have a degree of polymerization (DPn) about 20 relatively and low dispersity in the range of 1.07–1.66. Their optical properties were investigated by means of UV–vis and photoluminescence spectroscopies. The obtained polymers emitted light with maximum emission about 370 nm and high quantum yield ranging up to 79 %. Thus, it was confirmed that the utilization of fluorophore initiator for polymerization of non photoresponsive monomers is quite efficient for the preparation of photoluminescent polymers. 相似文献
19.
Orsolya Kinga Gondor Judit Tajti Kamirn ron Hamow Imre Majlth Gabriella Szalai Tibor Janda Magda Pl 《International journal of molecular sciences》2021,22(21)
Although the relationship between polyamines and photosynthesis has been investigated at several levels, the main aim of this experiment was to test light-intensity-dependent influence of polyamine metabolism with or without exogenous polyamines. First, the effect of the duration of the daily illumination, then the effects of different light intensities (50, 250, and 500 μmol m–2 s–1) on the polyamine metabolism at metabolite and gene expression levels were investigated. In the second experiment, polyamine treatments, namely putrescine, spermidine and spermine, were also applied. The different light quantities induced different changes in the polyamine metabolism. In the leaves, light distinctly induced the putrescine level and reduced the 1,3-diaminopropane content. Leaves and roots responded differently to the polyamine treatments. Polyamines improved photosynthesis under lower light conditions. Exogenous polyamine treatments influenced the polyamine metabolism differently under individual light regimes. The fine-tuning of the synthesis, back-conversion and terminal catabolism could be responsible for the observed different polyamine metabolism-modulating strategies, leading to successful adaptation to different light conditions. 相似文献
20.