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121.

Background

Environmental issues and shortage of fossil fuels have turned the public interest to the utilization of renewable, environmentally friendly fuels, such as ethanol. In order to minimize the competition between fuels and food production, researchers are focusing their efforts to the utilization of wastes and by-products as raw materials for the production of ethanol. household food wastes are being produced in great quantities in European Union and their handling can be a challenge. Moreover, their disposal can cause severe environmental issues (for example emission of greenhouse gasses). On the other hand, they contain significant amounts of sugars (both soluble and insoluble) and they can be used as raw material for the production of ethanol.

Results

Household food wastes were utilized as raw material for the production of ethanol at high dry material consistencies. A distinct liquefaction/saccharification step has been included to the process, which rapidly reduced the viscosity of the high solid content substrate, resulting in better mixing of the fermenting microorganism. This step had a positive effect in both ethanol production and productivity, leading to a significant increase in both values, which was up to 40.81% and 4.46 fold, respectively. Remaining solids (residue) after fermentation at 45% w/v dry material (which contained also the unhydrolyzed fraction of cellulose), were subjected to a hydrothermal pretreatment in order to be utilized as raw material for a subsequent ethanol fermentation. This led to an increase of 13.16% in the ethanol production levels achieving a final ethanol yield of 107.58 g/kg dry material.

Conclusions

In conclusion, the ability of utilizing household food waste for the production of ethanol at elevated dry material content has been demonstrated. A separate liquefaction/saccharification process can increase both ethanol production and productivity. Finally, subsequent fermentation of the remaining solids could lead to an increase of the overall ethanol production yield.  相似文献   
122.

Background

Recent experimental evidence suggests that socioeconomic characteristics of neighbourhoods influence cardiovascular health, but observational studies which examine deprivation across a wide range of cardiovascular diseases (CVDs) are lacking.

Methods

Record-linkage cohort study of 1.93 million people to examine the association between small-area socioeconomic deprivation and 12 CVDs. Health records covered primary care, hospital admissions, a myocardial infarction registry and cause-specific mortality in England (CALIBER). Patients were aged ≥30 years and were initially free of CVD. Cox proportional hazard models stratified by general practice were used.

Findings

During a median follow-up of 5.5 years 114,859 people had one of 12 initial CVD presentations. In women the hazards of all CVDs except abdominal aortic aneurysm increased linearly with higher small-area socioeconomic deprivation (adjusted HR for most vs. least deprived ranged from 1.05, 95%CI 0.83–1.32 for abdominal aortic aneurysm to 1.55, 95%CI 1.42–1.70 for heart failure; I2 = 81.9%, τ2 = 0.01). In men heterogeneity was higher (HR ranged from 0.89, 95%CI 0.75–1.06 for cardiac arrest to 1.85, 95%CI 1.67–2.04 for peripheral arterial disease; I2 = 96.0%, τ2 = 0.06) and no association was observed with stable angina, sudden cardiac death, subarachnoid haemorrhage, transient ischaemic attack and abdominal aortic aneurysm. Lifetime risk difference between least and most deprived quintiles was most marked for peripheral arterial disease in women (4.3% least deprived, 5.8% most deprived) and men (4.6% least deprived, 7.8% in most deprived); but it was small or negligible for sudden cardiac death, transient ischaemic attack, abdominal aortic aneurysm and ischaemic and intracerebral haemorrhage, in both women and men.

Conclusions

Associations of small-area socioeconomic deprivation with 12 types of CVDs were heterogeneous, and in men absent for several diseases. Findings suggest that policies to reduce deprivation may impact more strongly on heart failure and peripheral arterial disease, and might be more effective in women.  相似文献   
123.
The K146N/R147W substitutions in apoE3 were described in patients with a dominant form of type III hyperlipoproteinemia. The effects of these mutations on the in vivo functions of apoE were studied by adenovirus-mediated gene transfer in different mouse models. Expression of the apoE3[K146N/R147W] mutant in apoE-deficient (apoE−/−) or apoA-I-deficient (apoA-I−/−)×apoE−/− mice exacerbated the hypercholesterolemia and increased plasma apoE and triglyceride levels. In apoE−/− mice, the apoE3[K146N/R147W] mutant displaced apoA-I from the VLDL/LDL/HDL region and caused the accumulation of discoidal apoE-containing HDL. The WT apoE3 cleared the cholesterol of apoE−/− mice without induction of hypertriglyceridemia and promoted formation of spherical HDL. A unique property of the truncated apoE3[K146N/R147W]202 mutant, compared with similarly truncated apoE forms, is that it did not correct the hypercholesterolemia. The contribution of LPL and LCAT in the induction of the dyslipidemia was studied. Treatment of apoE−/− mice with apoE3[K146N/R147W] and LPL corrected the hypertriglyceridemia, but did not prevent the formation of discoidal HDL. Treatment with LCAT corrected hypertriglyceridemia and generated spherical HDL. The combined data indicate that the K146N/R147W substitutions convert the full-length and the truncated apoE3[K146N/R147W] mutant into a dominant negative ligand that prevents receptor-mediated remnant clearance, exacerbates the dyslipidemia, and inhibits the biogenesis of HDL.  相似文献   
124.
Glioma incidence rates in the United States are near 20000 new cases per year, with a median survival time of 14.6 mo for high-grade gliomas due to limited therapeutic options. The origins of these tumors and their many subtypes remain a matter of investigation. Evidence from mouse models of glioma and human clinical data have provided clues about the cell types and initiating oncogenic mutations that drive gliomagenesis, a topic we review here. There has been mixed evidence as to whether or not the cells of origin are neural stem cells, progenitor cells or differentiated progeny. Many of the existing murine models target cell populations defined by lineage-specific promoters or employ lineagetracing methods to track the potential cells of origin. Our ability to target specific cell populations will likely increase concurrently with the knowledge gleaned from an understanding of neurogenesis in the adult brain. The cell of origin is one variable in tumorigenesis, as oncogenes or tumor suppressor genes may differentially transform the neuroglial cell types. Knowledge of key driver mutations and susceptible cell types will allow us to understand cancer biology from a developmental standpoint and enable early interventional strategies and biomarker discovery.  相似文献   
125.
The speed of development, versatility and efficacy of mRNA-based vaccines have been amply demonstrated in the case of SARS-CoV-2. DNA vaccines represent an important alternative since they induce both humoral and cellular immune responses in animal models and in human trials. We tested the immunogenicity and protective efficacy of DNA-based vaccine regimens expressing different prefusion-stabilized Wuhan-Hu-1 SARS-CoV-2 Spike antigens upon intramuscular injection followed by electroporation in rhesus macaques. Different Spike DNA vaccine regimens induced antibodies that potently neutralized SARS-CoV-2 in vitro and elicited robust T cell responses. The antibodies recognized and potently neutralized a panel of different Spike variants including Alpha, Delta, Epsilon, Eta and A.23.1, but to a lesser extent Beta and Gamma. The DNA-only vaccine regimens were compared to a regimen that included co-immunization of Spike DNA and protein in the same anatomical site, the latter of which showed significant higher antibody responses. All vaccine regimens led to control of SARS-CoV-2 intranasal/intratracheal challenge and absence of virus dissemination to the lower respiratory tract. Vaccine-induced binding and neutralizing antibody titers and antibody-dependent cellular phagocytosis inversely correlated with transient virus levels in the nasal mucosa. Importantly, the Spike DNA+Protein co-immunization regimen induced the highest binding and neutralizing antibodies and showed the strongest control against SARS-CoV-2 challenge in rhesus macaques.  相似文献   
126.

Background

ErbB receptors, EGFR and HER2, have been implicated in the development and progression of colon cancer. Several intracellular pathways are mediated upon activation of EGFR and/or HER2 by EGF. However, there are limited data regarding the EGF-mediated signaling affecting functional cell properties and the expression of extracellular matrix macromolecules implicated in cancer progression.

Methods

Functional assays, such as cell proliferation, transwell invasion assay and migration were performed to evaluate the impact of EGFR/HER2 in constitutive and EGF-treated Caco-2 cells. Signaling pathways were evaluated using specific intracellular inhibitors. Western blot was also utilized to examine the phosphorylation levels of ERK1/2. Real time PCR was performed to evaluate gene expression of matrix macromolecules.

Results

EGF increases cell proliferation, invasion and migration and importantly, EGF mediates overexpression of EGFR and downregulation of HER2. The EGF–EGFR axis is the main pathway affecting colon cancer's invasive potential, proliferative and migratory ability. Intracellular pathways (PI3K-Akt, MEK1/2-Erk and JAK-STAT) are all implicated in the migratory profile. Notably, MT1- and MT2-MMP as well as TIMP-2 are downregulated, whereas uPA is upregulated via an EGF–EGFR network. The EGF–EGFR axis is also implicated in the expression of syndecan-4 and TIMP-1. However, glypican-1 upregulation by EGF is mainly mediated via HER2.

Conclusions and general significance

The obtained data highlight the crucial importance of EGF on the expression of both receptors and on the EGF–EGFR/HER2 signaling network, reveal the distinct roles of EGFR and HER2 on expression of matrix macromolecules and open a new area in designing novel agents in targeting colon cancer. This article is part of a Special Issue entitled Matrix-mediated cell behaviour and properties.  相似文献   
127.
128.
This study investigates the production of alginate microcapsules, which have been coated with the polysaccharide chitosan, and evaluates some of their properties with the intention of improving the gastrointestinal viability of a probiotic ( Bifidobacterium breve ) by encapsulation in this system. The microcapsules were dried by a variety of methods, and the most suitable was chosen. The work described in this Article is the first report detailing the effects of drying on the properties of these microcapsules and the viability of the bacteria within relative to wet microcapsules. The pH range over which chitosan and alginate form polyelectrolyte complexes was explored by spectrophotometry, and this extended into swelling studies on the microcapsules over a range of pHs associated with the gastrointestinal tract. It was shown that chitosan stabilizes the alginate microcapsules at pHs above 3, extending the stability of the capsules under these conditions. The effect of chitosan exposure time on the coating thickness was investigated for the first time by confocal laser scanning microscopy, and its penetration into the alginate matrix was shown to be particularly slow. Coating with chitosan was found to increase the survival of B. breve in simulated gastric fluid as well as prolong its release upon exposure to intestinal pH.  相似文献   
129.
Untreated and hydrothermally treated sorghum bagasse (SB) was hydrolyzed to simple sugars by the synergistic action of cellulases and hemicellulases produced by the fungi Fusarium oxysporum and Neurospora crassa. Synergism between the two lignocellulolytic systems was maximized with the application of higher fraction of N. crassa enzymes.Hydrothermolysis of SB was studied at a wide range of treatment times and temperatures. At intense pretreatment conditions (210 °C for 20 min; logR0 = 4.54), the residual hemicellulose percentage was 17.45%, while formation of inhibitory products, 5-hydromethyl-furfural (HMF), furfural, acetic and formic acid, (0.21, 0.51, 3.36 and 1.80 g/l, respectively) remained in acceptable levels.Maximum conversion of cellulose and total polysaccharides of the untreated SB were 23.18% and 18.79%, respectively. Combining hydrothermal treatment and enzymatic hydrolysis of released oligosaccharides and insoluble solids resulted in improvement of cellulose (approximately 15% increase) and total polysaccharides (two fold) hydrolysis compared to that of untreated SB.  相似文献   
130.
BackgroundNuclear translocation of large proteins is mediated through specific protein carriers, collectively named karyopherins (importins, exportins and adaptor proteins). Cargo proteins are recognized by importins through specific motifs, known as nuclear localization signals (NLS). However, only the NLS recognized by importin α and transportin (M9 NLS) have been identified so farMethodsAn unsupervised in silico approach was used, followed by experimental validation.ResultsWe identified the sequence EKRKI(E/R)(K/L/R/S/T) as an NLS signal for importin 7 recognition. This sequence was validated in the breast cancer cell line T47D, which expresses importin 7. Finally, we verified that importin 7-mediated nuclear protein transport is affected by cargo protein phosphorylation.ConclusionsThe NLS sequence for importin 7 was identified and we propose this approach as an identification method of novel specific NLS sequences for β-karyopherin family members.General significanceElucidating the complex relationships of the nuclear transporters and their cargo proteins may help in laying the foundation for the development of novel therapeutics, targeting specific importins, with an immediate translational impact.  相似文献   
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