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921.
Skin disorders are widespread around the world, affecting people of all ages, and oxidative stress represents one of the main causes of alteration in the normal physiological parameters of skin cells. In this work, we combined a natural protein, fibroin, with antioxidant compounds extracted in water from pomegranate waste. We demonstrate the effective and facile fabrication of bioactive and eco-sustainable films of potential interest for skin repair. The blended films are visually transparent (around 90%); flexible; stable in physiological conditions and in the presence of trypsin for 12 days; able to release the bioactive compounds in a controlled manner; based on Fickian diffusion; and biocompatible towards the main skin cells, keratinocytes and fibroblasts. Furthermore, reactive oxygen species (ROS) production tests demonstrated the high capacity of our films to reduce the oxidative stress induced in cells, which is responsible for various skin diseases.  相似文献   
922.
Congo red (CR) type self–assembled ribbon–like structures (SRLS) were previously shown to interact with some proteins, including albumin. SRLS also complex with some drugs with a flat, ring–shaped structure with aromatic characteristics, intercalating them into their ribbon structure. The combination of interaction with proteins and drug binding by SRLS enables the use of such systems for immunotargeting. It is especially interesting in the case of chemotherapeutic agents. The present experiments aimed to show that the model carrier system composed of supramolecular albumin and Congo red efficiently binds doxorubicin (Dox) and that the drug can be released at reduced pH. The presented results come from the studies on such complexes differing in the molar ratio of CR to Dox. The following methods were used for the analysis: electrophoresis, dialysis, gel filtration, spectral analysis, and analysis of the size of the hydrodynamic radius using the dynamic light scattering method (DLS). The applied methods confirmed the formation of the CR–Dox complex, with large dimensions and changed properties compared with free CR. The presented results show that albumin binds both CR and its complex with Dox. Various CR–Dox molar ratios, 5:1, 2:1, and 1:1, were analyzed. The confirmation of the possibility of releasing the drug from the carriers thus formed was also obtained. The presented research is important due to the search for optimal solutions for the use of SRLS in drug immunotargeting, with particular emphasis on chemotherapeutic agents.  相似文献   
923.
924.
Despite the popularity of JavaScript for client‐side web applications, there is a lack of effective software tools supporting JavaScript development and testing. The dynamic characteristics of JavaScript pose software engineering challenges such as program understanding and security. One important feature of JavaScript is that its objects support flexible mechanisms such as property changes at runtime and prototype‐based inheritance, making it difficult to reason about object behavior. We have performed an empirical study on real JavaScript applications to understand the dynamic behavior of JavaScript objects. We present metrics to measure behavior of JavaScript objects during execution (e.g., operations associated with an object, object size, and property type changes). We also investigated the behavioral patterns of observed objects to understand the coding or user interaction practices in JavaScript software. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
925.
In a previous study, we found that administration of ILB®, a new low molecular weight dextran sulphate, significantly improved mitochondrial functions and energy metabolism, as well as decreased oxidative/nitrosative stress, of brain tissue of rats exposed to severe traumatic brain injury (sTBI), induced by the closed-head weight-drop model of diffused TBI. Using aliquots of deproteinized brain tissue of the same animals of this former study, we here determined the concentrations of 24 amino acids of control rats, untreated sTBI rats (sacrificed at 2 and 7 days post-injury) and sTBI rats receiving a subcutaneous ILB® administration (at the dose levels of 1, 5 and 15 mg/kg b.w.) 30 min post-impact (sacrificed at 2 and 7 days post-injury). Additionally, in a different set of experiments, new groups of control rats, untreated sTBI rats and ILB®-treated rats (administered 30 min after sTBI at the dose levels of 1 or 5 mg/kg b.w.) were studied for their neurocognitive functions (anxiety, locomotor capacities, short- and long-term memory) at 7 days after the induction of sTBI. Compared to untreated sTBI animals, ILB® significantly decreased whole brain glutamate (normalizing the glutamate/glutamine ratio), glycine, serine and γ-aminobutyric acid. Furthermore, ILB® administration restored arginine metabolism (preventing nitrosative stress), levels of amino acids involved in methylation reactions (methionine, L-cystathionine, S-adenosylhomocysteine), and N-acetylaspartate homeostasis. The macroscopic evidences of the beneficial effects on brain metabolism induced by ILB® were the relevant improvement in neurocognitive functions of the group of animals treated with ILB® 5 mg/kg b.w., compared to the marked cognitive decline measured in untreated sTBI animals. These results demonstrate that ILB® administration 30 min after sTBI prevents glutamate excitotoxicity and normalizes levels of amino acids involved in crucial brain metabolic functions. The ameliorations of amino acid metabolism, mitochondrial functions and energy metabolism in ILB®-treated rats exposed to sTBI produced significant improvement in neurocognitive functions, reinforcing the concept that ILB® is a new effective therapeutic tool for the treatment of sTBI, worth being tested in the clinical setting.  相似文献   
926.
In this article, we describe the antimicrobial properties of a new composite based on anodic aluminium oxide (AAO) membranes containing propyl-copper-phosphonate units arranged at a predetermined density inside the AAO channels. The samples were prepared with four concentrations of copper ions and tested as antimicrobial drug on four different strains of Escherichia coli (K12, R2, R3 and R4). For comparison, the same strains were tested with three types of antibiotics using the minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests. Moreover, DNA was isolated from the analysed bacteria which was additionally digested with formamidopyrimidine-DNA glycosylase (Fpg) protein from the group of repair glycosases. These enzymes are markers of modified oxidised bases in nucleic acids produced during oxidative stress in cells. Preliminary cellular studies, MIC and MBC tests and digestion with Fpg protein after modification of bacterial DNA suggest that these compounds may have greater potential as antibacterial agents than antibiotics such as ciprofloxacin, bleomycin and cloxacillin. The described composites are highly specific for the analysed model Escherichia coli strains and may be used in the future as new substitutes for commonly used antibiotics in clinical and nosocomial infections in the progressing pandemic era. The results show much stronger antibacterial properties of the functionalised membranes on the action of bacterial membranes in comparison to the antibiotics in the Fpg digestion experiment. This is most likely due to the strong induction of oxidative stress in the cell through the breakdown of the analysed bacterial DNA. We have also observed that the intermolecular distances between the functional units play an important role for the antimicrobial properties of the used material. Hence, we utilised the idea of the 2D solvent to tailor them.  相似文献   
927.
Cold plasma (CP) technology is a technique used to change chemical and morphological characteristics of the surface of various materials. It is a newly emerging technology in agriculture used for seed treatment with the potential of improving seed germination and yield of crops. Wheat seeds were treated with glow (direct) or afterglow (indirect) low-pressure radio-frequency oxygen plasma. Chemical characteristics of the seed surface were evaluated by XPS and FTIR analysis, changes in the morphology of the seed pericarp were analysed by SEM and AFM, and physiological characteristics of the seedlings were determined by germination tests, growth studies, and the evaluation of α-amylase activity. Changes in seed wettability were also studied, mainly in correlation with functionalization of the seed surface and oxidation of lipid molecules. Only prolonged direct CP treatment resulted in altered morphology of the seed pericarp and increased its roughness. The degree of functionalization is more evident in direct compared to indirect CP treatment. CP treatment slowed the germination of seedlings, decreased the activity of α-amylase in seeds after imbibition, and affected the root system of seedlings.  相似文献   
928.
Alzheimer’s disease (AD) is a progressive condition and the most common cause of dementia worldwide. The neuropathological changes characteristic of the disorder can be successfully detected before the development of full-blown AD. Early diagnosis of the disease constitutes a formidable challenge for clinicians. CSF biomarkers are the in vivo evidence of neuropathological changes developing in the brain of dementia patients. Therefore, measurement of their concentrations allows for improved accuracy of clinical diagnosis. Moreover, AD biomarkers may provide an indication of disease stage. Importantly, the CSF biomarkers of AD play a pivotal role in the new diagnostic criteria for the disease, and in the recent biological definition of AD by the National Institute on Aging, NIH and Alzheimer’s Association. Due to the necessity of collecting CSF by lumbar puncture, the procedure seems to be an important issue not only from a medical, but also a legal, viewpoint. Furthermore, recent technological advances may contribute to the automation of AD biomarkers measurement and may result in the establishment of unified cut-off values and reference limits. Moreover, a group of international experts in the field of AD biomarkers have developed a consensus and guidelines on the interpretation of CSF biomarkers in the context of AD diagnosis. Thus, technological advancement and expert recommendations may contribute to a more widespread use of these diagnostic tests in clinical practice to support a diagnosis of mild cognitive impairment (MCI) or dementia due to AD. This review article presents up-to-date data regarding the usefulness of CSF biomarkers in routine clinical practice and in biomarkers research.  相似文献   
929.
The use of pointers presents serious problems for software productivity tools for software understanding, restructuring, and testing. Pointers enable indirect memory accesses through pointer dereferences, as well as indirect procedure calls (e.g., through function pointers in C). Such indirect accesses and calls can be disambiguated with pointer analysis. In this paper we evaluate the precision of one specific pointer analysis (the FA pointer analysis by Zhang et al.) for the purposes of call graph construction for C programs with function pointers. The analysis is incorporated in a production-strength code-browsing tool from Siemens Corporate Research in which the program call graph is used as a primary tool for code understanding.The FA pointer analysis uses an inexpensive, almost-linear, flow- and context-insensitive algorithm. To measure analysis precision, we compare the call graph constructed by this analysis with the most precise call graph obtainable by a large category of existing pointer analyses. Surprisingly, for all our data programs the FA analysis achieves the best possible precision. This result indicates that for the purposes of call graph construction, inexpensive pointer analyses may provide precision comparable to the precision of expensive pointer analyses.  相似文献   
930.
The extracellular matrix (ECM) is an important regulator of excitability and synaptic plasticity, especially in its highly condensed form, the perineuronal nets (PNN). In patients with drug-resistant mesial temporal lobe epilepsy (MTLE), hippocampal sclerosis type 1 (HS1) is the most common histopathological finding. This study aimed to evaluate the ECM profile of HS1 in surgically treated drug-resistant patients with MTLE in correlation to clinical findings. Hippocampal sections were immunohistochemically stained for aggrecan, neurocan, versican, chondroitin-sulfate (CS56), fibronectin, Wisteria floribunda agglutinin (WFA), a nuclear neuronal marker (NeuN), parvalbumin (PV), and glial-fibrillary-acidic-protein (GFAP). In HS1, besides the reduced number of neurons and astrogliosis, we found a significantly changed expression pattern of versican, neurocan, aggrecan, WFA-specific glycosylation, and a reduced number of PNNs. Patients with a lower number of epileptic episodes had a less intense diffuse WFA staining in Cornu Ammonis (CA) fields. Our findings suggest that PNN reduction, changed ECM protein, and glycosylation expression pattern in HS1 might be involved in the pathogenesis and persistence of drug-resistant MTLE by contributing to the increase of CA pyramidal neurons’ excitability. This research corroborates the validity of ECM molecules and their modulators as a potential target for the development of new therapeutic approaches to drug-resistant epilepsy.  相似文献   
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