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关键词： Collagen   Doxycycline   Nanofiber   Oxidative stress   Wound healing  

摘要： Electrospinning process has gained importance in the production of wound dressings in recent years. The wound dressings prepared by electrospinning method provide many advantages over conventional wound dressings. The aim of this study was to assess the histological, biochemical, and immunohistochemical evaluation of collagen/doxycycline loaded nanofiber wound dressing in both acute and chronic wound healing. Full-thickness wound model was created on rats and rats were divided in two main groups: normoglycemic (acute) and hyperglycemic (chronic) groups. Each group was divided into three sub groups: not treated (control) group, treated with nanofiber wound dressing group and treated with commercial product group. Wound closure rates were measured. Oxidative events were investigated by biochemical analyses. In addition to histological studies, matrix metalloproteinase, tissue inhibitor of metalloproteinase, vascular endothelial growth factor, basic-fibroblast growth factor, and von Willebrand factor levels were investigated with immunohistochemical studies. According to the biochemical analyses, it was concluded that the nanofiber wound dressing helps to increase antioxidant capacity and decrease lipid peroxidation. Immunohistochemical studies showed that nanofiber wound dressing enhanced angiogenesis and shortened the inflammatory phase. It was concluded that an effective and safe prototype nanofiber wound dressing, which has similar wound healing effect to the commercial product, has been developed to be used in acute or chronic wound treatment. (C) 2019 Elsevier Ltd and ISBI. All rights reserved.

摘要： The environmentally relevant xenobiotic esters of phthalic acid (PA), isophthalic acid (IPA) and terephthalic acid (TPA) are produced on a million ton scale annually and are predominantly used as plastic polymers or plasticizers. Degradation by microorganisms is considered as the most effective means of their elimination from the environment and proceeds via hydrolysis to the corresponding PA isomers and alcohols under oxic and anoxic conditions. Further degradation of PA, IPA and TPA differs fundamentally between anaerobic and aerobic microorganisms. The latter introduce hydroxyl functionalities by dioxygenases to facilitate subsequent decarboxylation by either aromatizing dehydrogenases or cofactor-free decarboxylases. In contrast, anaerobic bacteria activate the PA isomers to the respective thioesters using CoA ligases or CoA transferases followed by decarboxylation to the central intermediate benzoyl-CoA. Decarboxylases acting on the three PA CoA thioesters belong to the UbiD enzyme family that harbour a prenylated flavin mononucleotide (FMN) cofactor to achieve the mechanistically challenging decarboxylation. Capture of the extremely instable PA-CoA intermediate is accomplished by a massive overproduction of phthaloyl-CoA decarboxylase and a balanced production of PA-CoA forming/decarboxylating enzymes. The strategy of anaerobic phthalate degradation probably represents a snapshot of an ongoing evolution of a xenobiotic degradation pathway via a short-lived reaction intermediate.

关键词： Essential oils  

摘要： The present study was carried for the toxicological assessment of Cinnamomum tamala essential oil (CTEO) in vivo since no previous work has reported the sub-chronic toxicity in rats. Hence, the aim of the present study was to study for the first time sub-chronic toxicity of CTEO, extracted from C. tamala leaves, in Wistar rats. Recently, there is development of new food preservatives to increase the shelf life of food. The incorporation of CTEO as a food preservative could be a good alternative to synthetic compounds. For decades, C. tamala and its leaves are being used in food and pharmaceutical preparation. In order to fulfill the requirements suggested by the Scientific Committee on Food for safety assessment of substances used in food contact materials, sub-chronic studies are needed. Therefore, in vivo experiments have been conducted to assess the antidiabetic and antioxidant properties of CTEO, which also demands toxicity assessment. Practical applications Medicinal plants and herbs have been used since ancient times for their formulations and essential oils (EOs). Several studies have investigated the composition of EOs and plant extracts having nutritional and medicinal properties. Cinnamomum tamala essential oil (CTEO) is used in the food and pharmaceutical preparations as well as in traditional medicinal systems as a preservative and curative agent in various alignments. In the present study, the oral acute and sub-chronic toxicity of CTEO was assessed in Wistar rats, including the clinical, hematological, biochemical and pathological parameters. The repeated oral administration of CTEO showed no mortality, alterations in food and water intake, body weight, hematology and biochemistry, organ weight and histopathology. In conclusion, the use of CTEO in food and other pharmaceutical preparations may be safe due to its lack of toxicity in Wistar rats during the period of study.

关键词： ABC transporters   cystic fibrosis   nonsense mutations   translational read-through  

摘要： Key points Biochemical and biophysical characterizations of three nonsense mutations of cystic fibrosis transmembrane conductance regulator (CFTR) associated with a severe form of cystic fibrosis (CF) reveal the importance and heterogenous effects of the position of the premature termination codon (PTC) on the CFTR protein function. Electrophysiological studies of W1282X-CFTR, whose PTC is closer to the C-terminus of CFTR, suggest the presence of both C-terminus truncated CFTR proteins that are poorly functional and read-through, full-length products. For G542X- and E60X-CFTR, the only mechanism capable of generating functional proteins is the read-through, but the outcome of read-through products is highly variable depending on the interplay between the missense mutation caused by the read-through and the structural context of the protein. Pharmacological studies of these three PTCs with various CFTR modulators suggest position-dependent therapeutic strategies for these disease-inflicting mutations. About one-third of genetic diseases and cancers are caused by the introduction of premature termination codons (PTCs). In theory, the location of the PTC in a gene determines the alternative mechanisms of translation, including premature cessation or reinitiation of translation, and read-through, resulting in differential effects on protein integrity. In this study, we used CFTR as a model system to investigate the positional effect of the PTC because of its well-understood structure-function relationship and pathophysiology. The characterization of three PTC mutations, E60X-, G542X- and W1282X-CFTR revealed heterogenous effects of these PTCs on CFTR function. The W1282X mutation results in both C-terminus truncated and read-through proteins that are partially or fully functional. In contrast, only the read-through protein is functional with E60X- and G542X-CFTR, although abundant N-terminus truncated proteins due to reinitiation of translation were detected in E60X-CFT

关键词： platelets   transfusion   storage   cryopreservation  

摘要： Platelet cryopreservation has been investigated for several decades as an alternative to room temperature storage of platelet concentrates. The use of dimethylsulfoxide as a cryoprotectant has improved platelet storage and cryopreserved concentrates can be kept at 80 degrees C for two years. Cryopreserved platelets can serve as emergency backup to support stock crises or to disburden difficult logistic areas like rural or military regions. Cryopreservation significantly influences platelet morphology, decreases platelet activation and severely abrogates platelet aggregation. Recent data indicate that cryopreserved platelets have a procoagulant phenotype because thrombin and fibrin formation kicks in earlier compared to room temperature stored platelets. This happens both in static and hydrodynamic conditions. In a clinical setting, low 1-h post transfusion recoveries of cryopreserved platelets represent fast clearance from circulation which may be explained by changes to the platelet GPIb alpha receptor. Cryopreservation splits the concentrate in two platelet subpopulations depending on GPIb alpha expression levels. Further research is needed to unravel its physiological importance. Proving clinical efficacy of cryopreserved platelets is difficult because of the heterogeneity of indications and the ambiguity of outcome measures. The procoagulant character of cryopreserved platelets has increased interest for use in trauma stressing the need for double-blinded randomized clinical trials in actively bleeding patients.

关键词： antioxidant activity   barley   biochemical dynamics   solid-state fermentation  

摘要： Barley is an ancient and important functional crop. In this study, the biochemical and antioxidant dynamics of dehusked barley during co-fermentation with Lactobacillus plantarum and Rhizopus oryzae were investigated. Results showed that amino acid nitrogen, soluble protein, <10 kDa peptide, and free phenolic contents increased with fermentation time;whereas the lactic acid bacteria count, reducing sugar, and free flavonoid contents showed a tendency to increase first and then decrease. SDS-PAGE analysis indicated that bands at >25 and <18.4 kDa were shown with improved intensity with time, whereas bands at 18.4-25 kDa were disappeared. Additionally, fermentation time led to an increase in DPPH, hydroxyl, ABTS(+) radical scavenging activity, and ferric reducing antioxidant power. Thus, this study demonstrated that co-fermentation with L. plantarum and R. oryzae could improve nutrition and potential bioactivity of barley, and use barley as a good solid-state food carrier for probiotics. Practical applications Barley is rich in nutrition and has a huge production. However, due to its high-fiber and special protein composition, there is a certain palatability problem whether it is used to produce flour or other products. Therefore, most of the barley is destined to animal feed and malt, and only a small part is used directly for human consumption. Aiming at this problem, on the basis of the optimization of the fermentation process at early stage, our results further demonstrated co-fermentation with L. plantarum and R. oryzae could enhance the nutritional value and potential bioactivity of barley, thus providing a novel approach to develop functional barley food and improve the direct utilization rate of barley in food processing.

关键词： amyloid   crystal structure   molecular dynamics   protein aggregation   structural biology  

摘要： The molecular bases of amyloid aggregation propensity are still poorly understood, especially for proteins that display a stable folded native structure. A prototypic example is human beta-2 microglobulin (beta 2m), which, when accumulated in patients, gives rise to dialysis-related amyloidosis. Interestingly, although the physiologic concentration of beta 2m in mice is five times higher than that found in human patients, no amyloid deposits are observed in mice. Moreover, murine beta 2m (m beta 2m) not only displays a lower amyloid propensity both in vivo and in vitro but also inhibits the aggregation of human beta 2m in vitro. Here, we compared human and m beta 2m for their aggregation propensity, ability to form soluble oligomers, stability, three-dimensional structure and dynamics. Our results indicate that m beta 2m low-aggregation propensity is due to two concomitant aspects: the low-aggregation propensity of its primary sequence combined with the absence of high-energy amyloid-competent conformations under native conditions. The identification of the specific properties determining the low-aggregation propensity of mouse beta 2m will help delineate the molecular risk factors which cause a folded protein to aggregate.

关键词： Aquaculture   Life cycle   Reproduction   Sporulation inhibitors   Ulva   Chlorophyta   Land-based cultivation  

摘要： The green algal genus Ulva (Ulvophyceae) has been recently perceived as a model organism, due to its tractability for genetic analyses. This biomass is drawing considerable attention as a potential feedstock for energy security, including emerging applications in functional foods, bio-fuels and energy, pharmaceutical, biotechnological industries, etc. Nevertheless, unlike other commercially farmed seaweeds where clonal propagation is practiced, this genus solely relies on motile reproductive cells (zoospores or gametes) for seeding or seedling production. The culture practices encompass photobioreactor, land-based and open sea farming. The knowledge of reproduction is pivotal for efficient seeding technologies, selecting and domesticating fast growing varieties as well as genetic improvement. The successful induction of reproduction in Ulva spp. is being achieved through external environmental stimuli as well as by manipulating sporulation and swarming inhibitor concentration. However, comprehensive biochemical and molecular evidences are underdeveloped and further knowledge is imperative to improve aquaculture practice. This mini-review provides comprehensive insights into life cycle, spore formation, mechanisms for the induction of reproduction, biochemical and molecular aspects of sporulation besides advances in the farming of Ulva spp. with future prospective. The existing commercial trade of Japan about 1500 t dry annum(-1) is poised to become the leading industry with focus on niche, high-value products in the coming decade.

关键词： affective and cognitive behavior   chronic constriction injury   GABA and d-aspartate levels   ongoing- and mechanically evoked neural activity   prelimbic division of the medial prefrontal cortex  

摘要： The chronic constriction injury (CCI) of the sciatic nerve is a nerve injury-based model of neuropathic pain (NP). Comorbidities of NP such as depression, anxiety, and cognitive deficits are associated with a functional reorganization of the medial prefrontal cortex (mPFC). Here, we have employed an adapted model of CCI by placing one single loose ligature around the sciatic nerve in mice for investigating the alterations in sensory, motor, affective, and cognitive behavior and in electrophysiological and biochemical properties in the prelimbic division (PrL) of the mPFC. Our adapted model of CCI induced mechanical allodynia, motor, and cognitive impairments and anxiety- and depression-like behavior. In the PrL division of mPFC was observed an increase in GABA and a decrease in d-aspartate levels. Moreover an increase in the activity of neurons responding to mechanical stimulation with an excitation, mPFC (+), and a decrease in those responding with an inhibition, mPFC (-), was found. Altogether these findings demonstrate that a single ligature around the sciatic nerve was able to induce sensory, affective, cognitive, biochemical, and functional alterations already observed in other neuropathic pain models and it may be an appropriate and easily reproducible model for studying neuropathic pain mechanisms and treatments.

关键词： Rubisco   CO2 diffusion   mesophyll conductance   photorespiratory C-2 cycle   photosynthetic efficiency   photorespiratory bypass   yield improvement   photosynthesis  

摘要： Photorespiratory metabolism is essential for plants to maintain functional photosynthesis in an oxygen-containing environment. Because the oxygenation reaction of Rubisco is followed by the loss of previously fixed carbon, photorespiration is often considered a wasteful process and considerable efforts are aimed at minimizing the negative impact of photorespiration on the plant's carbon uptake. However, the photorespiratory pathway has also many positive aspects, as it is well integrated within other metabolic processes, such as nitrogen assimilation and C-1 metabolism, and it is important for maintaining the redox balance of the plant. The overall effect of photorespiratory carbon loss on the net CO2 fixation of the plant is also strongly influenced by the physiology of the leaf related to CO2 diffusion. This review outlines the distinction between Rubisco oxygenation and photorespiratory CO2 release as a basis to evaluate the costs and benefits of photorespiration.