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Simon Klepper Susan Jung Lara Dittmann Carol I. Geppert Arnd Hartmann Nicole Beier Regina Trollmann 《International journal of molecular sciences》2022,23(15)
Experimental in vivo data have recently shown complementary neuroprotective actions of rhEPO and growth hormone (rhGH) in a neonatal murine model of hypoxic brain injury. Here, we hypothesized that rhGH and rhEPO mediate stabilization of the blood–brain barrier (BBB) and regenerative vascular effects in hypoxic injury to the developing brain. Using an established model of neonatal hypoxia, neonatal mice (P7) were treated i.p. with rhGH (4000 µg/kg) or rhEPO (5000 IU/kg) 0/12/24 h after hypoxic exposure. After a regeneration period of 48 h or 7 d, cerebral mRNA expression of Vegf-A, its receptors and co-receptors, and selected tight junction proteins were determined using qRT-PCR and ELISA. Vessel structures were assessed by Pecam-1 and occludin (Ocln) IHC. While Vegf-A expression increased significantly with rhGH treatment (p < 0.01), expression of the Vegfr and TEK receptor tyrosine kinase (Tie-2) system remained unchanged. RhEPO increased Vegf-A (p < 0.05) and Angpt-2 (p < 0.05) expression. While hypoxia reduced the mean vessel area in the parietal cortex compared to controls (p < 0.05), rhGH and rhEPO prevented this reduction after 48 h of regeneration. Hypoxia significantly reduced the Ocln+ fraction of cortical vascular endothelial cells. Ocln signal intensity increased in the cortex in response to rhGH (p < 0.05) and in the cortex and hippocampus in response to rhEPO (p < 0.05). Our data indicate that rhGH and rhEPO have protective effects on hypoxia-induced BBB disruption and regenerative vascular effects during the post-hypoxic period in the developing brain. 相似文献
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Adolescent sexting – the electronic swapping of sexually intimate texts or images – has attracted significant media and policy attention. However, questions remain about the predictors of this phenomenon, in which mobile phones play a central role in adolescents’ exploration of sexuality. Therefore, a survey involving 498 adolescents aged between 15 and 18 years was conducted. The first aim of this study is to determine the predictive value of personal attitudes, subjective norm (SN) and perceived behavioural control by applying the theory of planned behaviour (TPB). As the second aim, we wish to assess the relative importance of the most salient beliefs underpinning the TPB components, since this will allow us to gain a more nuanced insight into the characteristics of adolescent sexting. Analyses reveal that SN is the most important predictor, followed by adolescents’ attitudes towards sexting. Perceived behavioural control is significantly but weakly associated with teenagers’ sexting intentions. Within SN, friends and romantic partners represent the most important sources of social pressure, while only positive behavioural outcomes are found to affect adolescents’ sexting intentions. The most important control belief affecting adolescents’ intention to sext is the belief that it occurs relatively more often among those whom adolescents feel they can trust entirely. 相似文献
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M. L. Bruschi E. H. G. Lara C. H. G. Martins A. H. C. Vinholis L. A. Casemiro H. Panzeri 《Drug development and industrial pharmacy》2013,39(2):229-238
ABSTRACTGelatin microparticles containing propolis ethanolic extractive solution were prepared by spray-drying technique. Particles with regular morphology, mean diameter ranging of 2.27 μm to 2.48 μm, and good entrapment efficiency for propolis were obtained. The in vitro antimicrobial activity of microparticles was evaluated against microorganisms of oral importance (Enterococcus faecalis, Streptococcus salivarius, Streptococcus sanguinis, Streptococcus mitis, Streptococcus mutans, Streptococcus sobrinus, Candida albicans, and Lactobacillus casei). The utilized techniques were diffusion in agar and determination of minimum inhibitory concentration. The choice of the method to evaluate the antimicrobial activity of microparticles showed be very important. The microparticles displayed activity against all tested strains of similar way to the propolis, showing greater activity against the strains of E. salivarius, S. sanguinis, S. mitis, and C. albicans. 相似文献
207.
Niranjan Patra Marco Salerno P. Davide Cozzoli Alberto C. Barone Luca Ceseracciu Francesca Pignatelli Riccardo Carzino Lara Marini Athanassia Athanassiou 《Composites Part B》2012,43(8):3114-3119
Thick films of nanocomposites made of poly(methyl methacrylate) matrix and colloidal anatase TiO2 nanorods fillers were prepared by solvent mixing and solution drop casting. Different concentrations of nanorods were tested in order to examine the influence of the nanoscale fillers on the composites material properties and structure. The thermal properties of the samples were investigated through thermogravimetric analysis, which showed an increase in thermal stability of the nanocomposites on increasing nanorods concentration, for the range of concentrations used. The viscoelastic properties were investigated through dynamic mechanical analysis, which showed an increase in both the storage and loss modulus on increasing nanorods concentration. The in-depth distribution of the TiO2 nanorods in the matrix was evaluated through cross-sectional transmission electron microscopy, which pointed out a uniform dispersion of mesoscale nanorods agglomerates with increasing diameter of 100–200 nm range on increasing nanorods concentration. 相似文献
208.
The surface chemistry of chloroform as an extreme-pressure lubricant additive at high concentrations
Carbon tetrachloride is an extremely good extreme-pressure (EP) lubricant additive at low concentrations (<3 wt% chlorine) since it can react to form a high-melting-point Fe3C antiseizure layer. In contrast, small hydrogen-containing additive molecules (CH2Cl2, CHCl3) decompose to form FeCl2 which melts at ~940 K and limits the maximum seizure load to ~3500 N as measured hi a pin and v-block apparatus. However, both thermodynamic calculations and results of a Mössbauer analysis of an iron foil heated in CHCl3 at 830 K indicate that iron carbide can be formed from chloroform. In addition, it is also found in that case that a plot of seizure load versus concentration, after initially forming a plateau, once again increases with higher additive concentrations (>4 wt% chlorine) in accord with the idea that a higher melting point carbide film can be formed. It has been shown previously that asymptotes in the plot of removal rate versus applied load correspond to melting of the interfacial anti-seizure film. When using 9.0 wt% chlorine from chloroform as the additive, a drastic increase in removal rate is found at an interfacial temperature of ~940 K corresponding to the melting of FeCl2 and an additional asymptote is evident at ~1500 K due to the melting of Fe3C in accord with the thermodynamic and Mössbauer results. 相似文献
209.
Exploitation of lettuce waste flour to increase bread functionality: effect on physical,nutritional, sensory properties and on consumer response 下载免费PDF全文
Stella Plazzotta Sandro Sillani Lara Manzocco 《International Journal of Food Science & Technology》2018,53(10):2290-2297
Phenol and fibre‐rich flour obtained by air‐drying and grinding of lettuce waste was partially substituted (26, 53, 170 and 575 g kg?1) to wheat flour to produce functional bread. The addition of flour progressively decreased dough leavening capacity while increased bread moisture and firmness. Lettuce waste flour significantly increased the polyphenolic content (up to 3.4 g GAE kg?1) of bread samples and enhanced their antioxidant activity by 200%. Bread containing 170 and 575 g kg?1 of lettuce waste flour presented sensory properties and consumer acceptability comparable to those of commercial wholemeal bread with similar rye bran content. Bread containing at least 170 g kg?1 of lettuce waste flour could be associated to nutritional claims related to its enhanced fibre content (>30 g kg?1). Data obtained by conjoint analysis demonstrate the possibility of increasing consumer preference for lettuce waste flour bread by proper nutritional (fibre content) and sustainability (lettuce waste valorisation) claims. 相似文献
210.
S. Shiffman J. Gitchell J. M. Pinney S. L. Burton K. E. Kemper E. A. Lara 《Tobacco control》1997,6(4):306-310