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51.
Alzheimer's disease (AD) is the most common form of dementia and is characterized by the presence of senile plaques and neurofibrillary tangles, along with synaptic loss. The underlying mechanisms of AD are not clarified yet, but oxidative stress and mitochondrial dysfunction are important factors. Overactivation of poly(adenosine diphosphate ribose) polymerase‐1 (PARP‐1) enzyme has been known to cause neuroinflammation and cell death in neurodegenerative processes. The aim of the present study was to investigate the protective effects of the PARP‐1 inhibitors, 3‐aminobenzamide (3‐AB) and nicotinamide (NA), against amyloid β peptide (1–42) (Aβ(1–42))‐induced oxidative damage and mitochondrial reduction capacity on isolated synaptosomes. Rats were injected intraperitoneally with 3‐AB (30–100 mg kg?1), NA (100–500 mg kg?1) or with saline for 7 days. Synaptosomes were incubated with 10–30 μM Aβ(1–42) or saline for 6 h at 37 °C. Ex vivo Aβ(1–42) treatment significantly induced oxidative stress and mitochondrial dysfunction in synaptosomes of the saline group, while synaptosomes of 3‐AB and NA groups showed significant decreases in lipid peroxidation, reactive oxygen species production and protein oxidation. Moreover, both NA and 3‐AB were able to improve the mitochondrial reduction capacity against Aβ(1–42). These data suggest that NA and 3‐AB may have protective effects in neurodegenerative processes because of the reduced levels of oxidative stress and the improvement of mitochondrial function. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
52.
All-trans retinoic acid (ATRA) has only limited single agent activity in AML without the PML-RARα fusion (non-M3 AML). In search of a sensitizing strategy to overcome this relative ATRA resistance, we investigated the potency of the HDAC class-I selective inhibitor entinostat in AML cell lines Kasumi-1 and HL-60 and primary AML blasts. Entinostat alone induced robust differentiation of both cell lines, which was enhanced by the combination with ATRA. This “priming” effect on ATRA-induced differentiation was at least equivalent to that achieved with the DNA hypomethylating agent decitabine, and could overall be recapitulated in primary AML blasts treated ex vivo. Moreover, entinostat treatment established the activating chromatin marks acH3, acH3K9, acH4 and H3K4me3 at the promoter of the RARβ2 gene, an essential mediator of retinoic acid (RA) signaling in different solid tumor models. Similarly, RARβ2 promoter hypermethylation (which in primary blasts from 90 AML/MDS patients was surprisingly infrequent) could be partially reversed by decitabine in the two cell lines. Re-induction of the epigenetically silenced RARβ2 gene was achieved only when entinostat or decitabine were given prior to ATRA treatment. Thus in this model, reactivation of RARβ2 was not necessarily required for the differentiation effect, and pharmacological RARβ2 promoter demethylation may be a bystander phenomenon rather than an essential prerequisite for the cellular effects of decitabine when combined with ATRA. In conclusion, as a “priming” agent for non-M3 AML blasts to the differentiation-inducing effects of ATRA, entinostat is at least as active as decitabine, and both act in part independently from RARβ2. Further investigation of this treatment combination in non-M3 AML patients is therefore warranted, independently of RARβ2 gene silencing by DNA methylation.  相似文献   
53.
Abstract

Small interfering RNA (siRNA)-based gene silencing strategy has high potential on suppressing specific molecular targets, involved in cancer progression. However, the lack of an effective nanocarrier system that safely delivers siRNA to its target still limits the clinical applications of siRNA. This study aimed to develop albumin-sericin nanoparticles (Alb-Ser NPs) as a novel siRNA delivery system for laryngeal cancer treatment. Nanoparticle formulations composed of albumin and sericin at different ratios (1:1, 2:1, 1:2 w/w) were synthesized by desolvation method. The nanoparticles were modified with poly-L-lysine (PLL) for siRNA binding and decorated with hyaluronic acid (HA) to target laryngeal cancer cell line, Hep-2. HA/PLL/Alb-Ser NPs were individually loaded with siRNAs for casein kinase 2 (CK2), Absent, Small, or Homeotic-Like (ASH2L), and Cyclin D1 genes, which are overexpressed in Hep-2 cells. Downregulation of genes was confirmed by real-time PCR (RT-PCR). Size, morphological, and thermogravimetric characterizations revealed that Alb-Ser NPs having 2:1 (w/w) ratio are the most optimized formulation. Between 36.8 and 61.3% of siRNA entrapment efficiencies were achieved. HA/PLL-siRNA/Alb-Ser (2:1) NPs-mediated gene silencing resulted in a significant inhibition of cell growth and induction of apoptosis in cells. Our findings showed that HA/PLL/Alb-Ser (2:1) NPs were promising as a siRNA carrier.  相似文献   
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55.
Matrix-Assisted Laser Desorption Ionization-Imaging Mass Spectrometry (MALDI-IMS) is a rapidly evolving method used for the in situ visualization and localization of molecules such as drugs, lipids, peptides, and proteins in tissue sections. Therefore, molecules such as lipids, for which antibodies and other convenient detection reagents do not exist, can be detected, quantified, and correlated with histopathology and disease mechanisms. Furthermore, MALDI-IMS has the potential to enhance our understanding of disease pathogenesis through the use of “biochemical histopathology”. Herein, we review the underlying concepts, basic methods, and practical applications of MALDI-IMS, including post-processing steps such as data analysis and identification of molecules. The potential utility of MALDI-IMS as a companion diagnostic aid for lipid-related pathological states is discussed.  相似文献   
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A new series of N-(2-hydroxy-4(or 5)-nitro/aminophenyl)benzamide and phenylacetamide derivatives (1a-1n, 2a-2n) were synthesized and evaluated for antibacterial and antifungal activities against Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, and their drug-resistant isolate. Microbiological results indicated that the compounds possessed a broad spectrum of activity against the tested microorganisms at MIC values between 500 and 1.95 microg/ml. Benzamide derivative 1d exhibited the greatest activity with MIC values of 1.95, 3.9, and 7.8 microg/ml against drug-resistant B. subtilis, B. subtilis, and S. aureus, respectively.  相似文献   
58.
This research was conducted to investigate the suitability of peanut hull to produce general purpose particleboards. A series of panels were produced using peanut hull and mixture of peanut hull and European Black pine wood chips. Particleboards were manufactured using various hull ratios in the mixture (0%, 25%, 50%, 75% and 100%). Urea formaldehyde adhesive was utilized in board production and boards were produced to target panel's density of 0.7 g/cm3. Panels were tested for some physical (water absorption and thickness swelling), chemical (holocellulose content, lignin content, alcohol-benzene solubility, 1% NaOH solubility, hot water solubility and cold water solubility) and mechanical (modulus of rupture, modulus of elasticity and internal bond) properties. The main observation was that increase in peanut hull in the mixture resulted in a decrease in mechanical and physical properties of produced panels and panel including 25% hull in the mixture solely met the standard required by TS-EN 312 standard. Conclusively, a valuable renewable natural resource, peanut hull could be utilized in panel production while it has been mixed to the wood chips.  相似文献   
59.
Application of single nucleotide polymorphisms (SNPs) is revolutionizing human bio-medical research. However, discovery of polymorphisms in low polymorphic species is still a challenging and costly endeavor, despite widespread availability of Sanger sequencing technology. We present CRoPS as a novel approach for polymorphism discovery by combining the power of reproducible genome complexity reduction of AFLP with Genome Sequencer (GS) 20/GS FLX next-generation sequencing technology. With CRoPS, hundreds-of-thousands of sequence reads derived from complexity-reduced genome sequences of two or more samples are processed and mined for SNPs using a fully-automated bioinformatics pipeline. We show that over 75% of putative maize SNPs discovered using CRoPS are successfully converted to SNPWave assays, confirming them to be true SNPs derived from unique (single-copy) genome sequences. By using CRoPS, polymorphism discovery will become affordable in organisms with high levels of repetitive DNA in the genome and/or low levels of polymorphism in the (breeding) germplasm without the need for prior sequence information.  相似文献   
60.
In this study, performance of a lab-scale hybrid up-flow anaerobic sludge blanket (UASB) reactor, treating a chemical synthesis-based pharmaceutical wastewater, was evaluated under different operating conditions. This study consisted of two experimental stages: first, acclimation to the pharmaceutical wastewater and second, determination of maximum loading capacity of the hybrid UASB reactor. Initially, the carbon source in the reactor feed came entirely from glucose, applied at an organic loading rate (OLR) 1 kg COD/m(3) d. The OLR was gradually step increased to 3 kg COD/m(3) d at which point the feed to the hybrid UASB reactor was progressively modified by introducing the pharmaceutical wastewater in blends with glucose, so that the wastewater contributed approximately 10%, 30%, 70%, and ultimately, 100% of the carbon (COD) to be treated. At the acclimation OLR of 3 kg COD/m(3) d the hydraulic retention time (HRT) was 2 days. During this period of feed modification, the COD removal efficiencies of the anaerobic reactor were 99%, 96%, 91% and 85%, and specific methanogenic activities (SMA) were measured as 240, 230, 205 and 231 ml CH(4)/g TVS d, respectively. Following the acclimation period, the hybrid UASB reactor was fed with 100% (w/v) pharmaceutical wastewater up to an OLR of 9 kg COD/m(3) d in order to determine the maximum loading capacity achievable before reactor failure. At this OLR, the COD removal efficiency was 28%, and the SMA was measured as 170 ml CH(4)/g TVS d. The hybrid UASB reactor was found to be far more effective at an OLR of 8 kg COD/m(3) d with a COD removal efficiency of 72%. At this point, SMA value was 200 ml CH(4)/g TVS d. It was concluded that the hybrid UASB reactor could be a suitable alternative for the treatment of chemical synthesis-based pharmaceutical wastewater.  相似文献   
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