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51.
Collagen sponges loaded with polyphenols from Hamamelis virginiana were investigated as active materials for chronic wound dressings, evaluating in vitro the inhibition of two major enzymes that impair the wound healing process - myeloperoxidase (MPO) and collagenase. Prior to polyphenols loading, collagen was cross-linked with genipin to improve its biostability. The effect of genipin cross-linking and polyphenol concentration in the development of mechanically and enzymatically stable sponges was studied. The tensile strength of the cross-linked collagen increased with the increase of the cross-linking degree, coupled to decrease in the elongation and the swelling capacity of the sponges. The stability of the sponges to collagenase digestion reached maximum when 1 mM genipin was used. However, the biostability decreased more than 10-fold after loading the sponges with polyphenols (0.5 mg/mL), nevertheless, this effect was partially overcome using higher concentration of polyphenols (1 and 2 mg/mL) to inhibit collagenase. Moreover, the polyphenols released from the sponges were sufficient for complete inhibition of MPO activity. No considerable cytotoxicity of the genipin cross-linked collagen loaded with polyphenols was observed evaluating the NIH 3T3 fibroblasts viability.  相似文献   
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The bacterial flora of colonic aspirates taken after oral administration of a polyethylene glycol-electrolyte lavage solution to patients undergoing colonoscopy was analyzed by standard bacteriological methods and DNA hybridization techniques. The data were compared with those for normal feces collected from the same patients the day before treatment. The results indicate that the bacterial composition of feces differs from individual to individual but is not altered by the oral intake of a polyethylene glycol-electrolyte lavage solution. This pilot study demonstrates that routine colonoscopy aspirates taken after standard colonoscopy preparation accurately reflect the microflora of feces and therefore may be used in large-scale epidemiological studies.  相似文献   
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Trichoderma spp. is one of the most commonly used biological control agents against plant pathogens. This fungus produces changes in plant metabolism, thus increasing growth and enhancing resistance to biotic and abiotic stresses. However, its modes of action remain to be defined. In the first hours of interaction between cucumber plant roots and Trichoderma asperellum strain T34, salicylic and jasmonic acid levels and typical antipathogenic peroxidase activity increase in the cotyledons to different degrees depending on the applied concentration of the fungi. The use of 2-DE protein profiling and MS analysis allowed us to identify 28 proteins whose expression was affected in cotyledons after cucumber root colonization by Trichoderma applied at high concentrations: 17 were found to be up-regulated while 11 were down-regulated. Proteins involved in ROS scavenging, stress response, isoprenoid and ethylene biosynthesis, and in photosynthesis, photorespiration, and carbohydrate metabolism were differentially regulated by Trichoderma. The proteome changes found in this study help to give an understanding of how Trichoderma-treated plants become more resistant to pathogen attacks through the changes in expression of a set of defence-oriented proteins which can directly protect the plant or switch the metabolism to a defensive, nonassimilatory state.  相似文献   
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Hybridisation is increasingly recognised as an important cause of diversification and adaptation. Here, we show how divergence in male secondary sexual characters between two lineages of the common wall lizard (Podarcis muralis) gives rise to strong asymmetries in male competitive ability and mating success, resulting in asymmetric hybridisation upon secondary contact. Combined with no negative effects of hybridisation on survival or reproductive characters in F1‐hybrids, these results suggest that introgression should be asymmetric, resulting in the displacement of sexual characters of the sub‐dominant lineage. This prediction was confirmed in two types of secondary contact, across a natural contact zone and in two introduced populations. Our study illustrates how divergence in sexually selected traits via male competition can determine the direction and extent of introgression, contributing to geographic patterns of genetic and phenotypic diversity.  相似文献   
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ObjectiveIt is known that there is a high prevalence of certain anxiety disorders among schizophrenic patients, especially panic disorder and social phobia. However, the neural underpinnings of the comorbidity of such anxiety disorders and schizophrenia remain unclear. Our study aims to determine the neuroanatomical basis of the co-occurrence of schizophrenia with panic disorder and social phobia.MethodsVoxel-based morphometry was used in order to examine brain structure and to measure between-group differences, comparing magnetic resonance images of 20 anxious patients, 20 schizophrenic patients, 20 schizophrenic patients with comorbid anxiety, and 20 healthy control subjects.ResultsCompared to the schizophrenic patients, we observed smaller grey-matter volume (GMV) decreases in the dorsolateral prefrontal cortex and precentral gyrus in the schizophrenic-anxiety group. Additionally, the schizophrenic group showed significantly reduced GMV in the dorsolateral prefrontal cortex, precentral gyrus, orbitofrontal cortex, temporal gyrus and angular/inferior parietal gyrus when compared to the control group.ConclusionsOur findings suggest that the comorbidity of schizophrenia with panic disorder and social phobia might be characterized by specific neuroanatomical and clinical alterations that may be related to maladaptive emotion regulation related to anxiety. Even thought our findings need to be replicated, our study suggests that the identification of neural abnormalities involved in anxiety, schizophrenia and schizophrenia-anxiety may lead to an improved diagnosis and management of these conditions.  相似文献   
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BackgroundAccording to the “World Cancer Research Fund” and the “American Institute of Cancer Research” (WCRF/AICR) one in four cancer cases could be prevented through a healthy diet, weight control and physical activity.ObjectiveTo explore the association between the WCRF/AICR recommendations and risk of breast cancer.MethodsDuring the period 2006 to 2011 we recruited 973 incident cases of breast cancer and 973 controls from 17 Spanish Regions. We constructed a score based on 9 of the WCRF/AICR recommendations for cancer prevention:: 1)Maintain adequate body weight; 2)Be physically active; 3)Limit the intake of high density foods; 4)Eat mostly plant foods; 5)Limit the intake of animal foods; 6)Limit alcohol intake; 7)Limit salt and salt preserved food intake; 8)Meet nutritional needs through diet; S1)Breastfeed infants exclusively up to 6 months. We explored its association with BC by menopausal status and by intrinsic tumor subtypes (ER+/PR+ & HER2-; HER2+; ER&PR-&HER2-) using conditional and multinomial logistic models respectively.ResultsOur results point to a linear association between the degree of noncompliance and breast cancer risk. Taking women who met 6 or more recommendations as reference, those meeting less than 3 showed a three-fold excess risk (OR=2.98(CI95%:1.59-5.59)), especially for postmenopausal women (OR=3.60(CI95%:1.24;10.47)) and ER+/PR+&HER2- (OR=3.60(CI95%:1.84;7.05)) and HER2+ (OR=4.23(CI95%:1.66;10.78)) tumors. Noncompliance of recommendations regarding the consumption of foods and drinks that promote weight gain in premenopausal women (OR=2.24(CI95%:1.18;4.28); p for interaction=0.014) and triple negative tumors (OR=2.93(CI95%:1.12-7.63)); the intake of plant foods in postmenopausal women (OR=2.35(CI95%:1.24;4.44)) and triple negative tumors (OR=3.48(CI95%:1.46-8.31)); and the alcohol consumption in ER+/PR+&HER2- tumors (OR=1.52 (CI95%:1.06-2.19)) showed the strongest associations.ConclusionBreast cancer prevention might be possible by following the “World Cancer Research Fund” and the “American Institute of Cancer Research” recommendations, even in settings like Spain, where a high percentage of women already comply with many of them.  相似文献   
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Habitat invasion by alien plants is strongly modulated by environmental and landscape factors. However, the effect of landscape history remains largely unknown, despite the fact that it could play an important role in many stages of invasion processes, even long after land-use changes have occurred determining invasion debts. We analysed the effects of past landscape and recent changes therein, together with habitat type and current context (i.e. climate, topography and landscape), on three components of the invasion process at habitat scale: alien species presence (i.e. at least one alien species occurring), richness (number of species found) and abundance (mean species cover). We selected 531 plots in nine habitat types in Barcelona province (7725 km2) and recorded alien (neophyte) species cover. We performed Generalized Linear Models on these invasion components using the generated data and a set of predictors of habitat, context and landscape factors obtained from plot sampling and digital cartography. The results show that invasion components are affected by diverse habitat and context factors and, in some cases, by landscape history. Alien species presence is influenced by habitat type and the current environmental context, and by the number of habitat changes in the adjacent landscape; on the other hand, species richness is only associated with the current context and species abundance is only influenced by historical cropland cover. The association between alien species presence and abundance and past and recent landscape changes suggests the existence of accumulated invasion debts at habitat scale that might be relevant to habitat management.  相似文献   
60.
Stable genetic transformation of plants is a low-efficiency process, and identification of positive transformants usually relies on screening for expression of a co-transformed marker gene. Often this involves germinating seeds on solid media containing a selection reagent. Germination on solid media requires surface sterilization of seeds and careful aseptic technique to prevent microbial contamination, but surface sterilization techniques are time consuming and can cause seed mortality if not performed carefully. We developed an antimicrobial cocktail that can be added to solid media to inhibit bacterial and fungal growth without impairing germination, allowing us to bypass the surface sterilization step. Adding a combination of terbinafine (1 μM) and timentin (200 mg l−1) to Murashige and Skoog agar delayed the onset of observable microbial growth and did not affect germination of non-sterile seeds from 10 different wild-type and mutant Arabidopsis thaliana accessions. We named this antimicrobial solid medium “MSTT agar”. Seedlings sown in non-sterile conditions could be maintained on MSTT agar for up to a week without observable contamination. This medium was compatible with rapid screening methods for hygromycin B, phosphinothricin (BASTA) and nourseothricin resistance genes, meaning that positive transformants can be identified from non-sterile seeds in as little as 4 days after stratification, and transferred to soil before the onset of visible microbial contamination. By using MSTT agar we were able to select genetic transformants on solid media without seed surface sterilization, eliminating a tedious and time-consuming step.  相似文献   
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