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1.
Therapeutic approaches providing effective medication for Alzheimer’s disease (AD) patients after disease onset are urgently needed. Previous studies in AD mouse models suggested that physical exercise or changed lifestyle can delay AD-related synaptic and memory dysfunctions when treatment started in juvenile animals long before onset of disease symptoms, while a pharmacological treatment that can reverse synaptic and memory deficits in AD mice was thus far not identified. Repurposing food and drug administration (FDA)-approved drugs for treatment of AD is a promising way to reduce the time to bring such medication into clinical practice. The sphingosine-1 phosphate analog fingolimod (FTY720) was approved recently for treatment of multiple sclerosis patients. Here, we addressed whether fingolimod rescues AD-related synaptic deficits and memory dysfunction in an amyloid precursor protein/presenilin-1 (APP/PS1) AD mouse model when medication starts after onset of symptoms (at five months). Male mice received intraperitoneal injections of fingolimod for one to two months starting at five to six months. This treatment rescued spine density as well as long-term potentiation in hippocampal cornu ammonis-1 (CA1) pyramidal neurons, that were both impaired in untreated APP/PS1 animals at six to seven months of age. Immunohistochemical analysis with markers of microgliosis (ionized calcium-binding adapter molecule 1; Iba1) and astrogliosis (glial fibrillary acid protein; GFAP) revealed that our fingolimod treatment regime strongly down regulated neuroinflammation in the hippocampus and neocortex of this AD model. These effects were accompanied by a moderate reduction of Aβ accumulation in hippocampus and neocortex. Our results suggest that fingolimod, when applied after onset of disease symptoms in an APP/PS1 mouse model, rescues synaptic pathology that is believed to underlie memory deficits in AD mice, and that this beneficial effect is mediated via anti-neuroinflammatory actions of the drug on microglia and astrocytes.  相似文献   
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Nonspherical drops are of interest in the formation of microcapsules in life sciences like food, pharmacy, and cosmetics, agro and fine chemicals as well as material sciences. Out of many systems, particle‐stabilized emulsion drops, so‐called Pickering emulsions, exhibit an interesting formulation. Systems with Pickering particles applied in an excess amount were investigated. During deformation, the particles fully covered the enlarged drop interfaces and prevented its relaxation to a spherical drop shape. Nonspherical drops could be produced in simple shear flow using an adequate process routine. The production in a simple device is a promising high‐throughput alternative to microfluidic devices.  相似文献   
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Lipolysis is the biochemical pathway responsible for the catabolism of cellular triacylglycerol (TG). Lipolytic TG breakdown is a central metabolic process leading to the generation of free fatty acids (FA) and glycerol, thereby regulating lipid, as well as energy homeostasis. The precise tuning of lipolysis is imperative to prevent lipotoxicity, obesity, diabetes and other related metabolic disorders. Here, we present our finding that miR-124a attenuates RNA and protein expression of the major TG hydrolase, adipose triglyceride lipase (ATGL/PNPLA2) and its co-activator comparative gene identification 58 (CGI-58/ABHD5). Ectopic expression of miR-124a in adipocytes leads to reduced lipolysis and increased cellular TG accumulation. This phenotype, however, can be rescued by overexpression of truncated Atgl lacking its 3''UTR, which harbors the identified miR-124a target site. In addition, we observe a strong negative correlation between miR-124a and Atgl expression in various murine tissues. Moreover, miR-124a regulates the expression of Atgl and Cgi-58 in murine white adipose tissue during fasting as well as the expression of Atgl in murine liver, during fasting and re-feeding. Together, these results point to an instrumental role of miR-124a in the regulation of TG catabolism. Therefore, we suggest that miR-124a may be involved in the regulation of several cellular and organismal metabolic parameters, including lipid storage and plasma FA concentration.  相似文献   
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Objective

Proton density (PD) mapping requires correction for the receive profile (RP), which is frequently performed via bias-field correction. An alternative RP-mapping method utilizes a comparison of uncorrected PD-maps and a value ρ(T1) directly derived from T1-maps via the Fatouros equation. This may be problematic in multiple sclerosis (MS), if respective parameters are only valid for healthy brain tissue. We aimed to investigate whether the alternative method yields correct PD values in MS patients.

Materials/methods

PD mapping was performed on 27 patients with relapsing-remitting MS and 27 healthy controls, utilizing both methods, yielding reference PD values (PDref, bias-field method) and PDalt (alternative method).

Results

PDalt-values closely matched PDref, both for patients and controls. In contrast, ρ(T1) differed by up to 3 % from PDref, and the voxel-wise correlation between PDref and ρ(T1) was reduced in a patient subgroup with a higher degree of disability. Still, discrepancies between ρ(T1) and PDref were almost identical across different tissue types, thus translating into a scaling factor, which cancelled out during normalization to 100 % in CSF, yielding a good agreement between PDalt and PDref.

Conclusion

RP correction utilizing the auxiliary parameter ρ(T1) derived via the Fatouros equation provides accurate PD results in MS patients, in spite of discrepancies between ρ(T1) and actual PD values.
  相似文献   
8.
Self‐setting resorbable phosphate cements are characterized by an excellent biocompatibility and bioactivity. However, poor mechanical properties restrict their application. Most studies which characterize phosphate cements mechanically focus on strength measurements. Examinations of mechanical reliability and facture toughness were hardly performed. In this study, calcium phosphate whisker‐reinforced magnesium‐ammonium‐phosphate (struvite) cements were examined at the whisker–matrix interface and the measured strength, reliability and toughness values were correlated to these observations. Moreover, the toughening mechanisms were evaluated. It was shown that whisker incorporation is not beneficial for material strength. It led to a strength decrease from 29.8 to 21.8 MPa by the incorporation of 15 vol% calcium‐deficient hydroxyapatite (CDHA) whiskers compared to the pure struvite cement. Weibull statistics and microstructural observations revealed that this is caused by the whisker–matrix interface, which acts as a flaw. In contrast with that, the reliability increases upon whisker incorporation. Furthermore, the critical stress intensity factor KIC as well as the work‐of‐fracture γwof increase from 0.52 to 0.60 MPam1/2 and from 9.5 to 12.9 J/m² by the addition of 15 vol% CDHA whiskers compared to the original struvite cement. It was shown that whisker pull‐out and crack deflection are the main mechanisms responsible for this increase.  相似文献   
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The benefits that high‐pressure thermal sterilization offers as an emerging technology could be used to produce a better overall food quality. Due to shorter dwell times and lower thermal load applied to the product in comparison to the thermal retorting, lower numbers and quantities of unwanted food processing contaminants (FPCs), for example, furan, acrylamide, HMF, and MCPD‐esters could be formed. Two spore strains were used to test the technique; Geobacillus stearothermophilus and Bacillus amyloliquefaciens, over the temperature range 90 to 121 °C at 600 MPa. The treatments were carried out in baby food puree and ACES‐buffer. The treatments at 90 and 105 °C showed that G. stearothermophilus is more pressure‐sensitive than B. amyloliquefaciens. The formation of FPCs was monitored during the sterilization process and compared to the amounts found in retorted samples of the same food. The amounts of furan could be reduced between 81% to 96% in comparison to retorting for the tested temperature pressure combination even at sterilization conditions of F0‐value in 7 min.  相似文献   
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