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751.
Leucocytes contain an urokinase inhibitor, that can be inactivated by cathepsin D. In this work biochemical and immunological studies on the inactivation of this inhibitor by cathepsin D are presented. Examinations by polyacrylamide gel electrophoresis and SDS electrophoresis indicate that cathepsin D inactivates urokinase inhibitor by hydrolysis of the inhibitor molecule and that the degradation needed for total inactivation is different from that for formation of the precipitin line with antibodies. The conversion of active inhibitor into inactive protein proceeds catalytically.  相似文献   
752.
Many strains of a pathogenic fungus were isolated from diseased sunflower leaf tissue. According to their characteristics they belonged to the genus Septoria . Leaf speck symptoms, characteristic for spontaneous infection, were also reproduced by artificial inoculation of sunflower plants in the greenhouse.
Comparing the morphological, cultural and pathogenic properties of the isolated fungus with other sunflower pathogens, it was indicated that the strains, originating from diseased sunflower leaves represented a new, so far not described species. Therefore, for the causal agent of this disease, the name Septoria helianthina Petrov & Arsenijevic was suggested.  相似文献   
753.
To understand more fully the structure and evolution of the SOX3 protein, we comparatively analyzed its orthologs in vertebrates. Since complex disorders are associated with human SOX3 polyalanine expansions, our investigation focused on both compositional and evolutionary analysis of various homopolymeric amino acid tracts observed in SOX3 orthologs. Our analysis revealed that the observed homopolymeric alanine, glycine, and proline tracts are mammal-specific, except for one polyglycine tract present in birds. Since it is likely that the SOX3 protein acquired additional roles in brain development in Eutheria, we might speculate that development of novel brain functions during the course of evolution was affected, at least in part, by such structural–functional changes in the SOX3 protein.  相似文献   
754.
Thymus longicaulis C. Presl is a small aromatic perennial herb used as a traditional remedy for cold, flu and cough. Composition of the essential oil of T. longicaulis from Croatia and its in vitro antimicrobial activity against the most common respiratory pathogens were evaluated. The yield of essential oil obtained by hydrodistillation from aerial plant parts was 1.2%. According to the GC-MS analysis, a total of forty one compounds (99%) were identified. Thymol (46.3%), ??-terpinene (16.2%), thymyl methyl ether (11.4%), and p-cymene (9.4%) were the main components. Antimicrobial activity of the essential oil against six clinically isolated bacterial and yeast strains was determined using standard disc agar diffusion method and microdilution broth assay. The essential oil exhibited antimicrobial activity towards all tested respiratory pathogens. The most sensitive strains were Haemophilus influenzae and Streptococcus pneumoniae(MIC=0.78 mg/mL), while Staphylococcus aureus was the most resistant (MIC>25.00 mg/mL). Our results indicate that T. longicaulis essential oil could be effective against clinically relevant respiratory pathogens which have the ability to develop resistance to antimicrobial drugs.  相似文献   
755.
756.
Haptoglobin (Hp) is a positive acute phase protein, synthesized in the liver, with four N-glycosylation sites carrying mainly complex type N-glycans. Its glycosylation is altered in different types of diseases but still has not been extensively studied mainly due to analytical challenges, especially the lack of a fast, efficient, and robust high-throughput Hp isolation procedure. Here, we describe the development of a high-throughput method for Hp enrichment from human plasma, based on monolithic chromatographic support in immunoaffinity mode and downstream Hp N-glycome analysis by hydrophilic interaction ultrahigh-performance liquid chromatography with fluorescent detection (HILIC–UHPLC–FLR). Chromatographic monolithic supports in a 96-well format enable fast, efficient, and robust Hp enrichment directly from diluted plasma samples. The N-glycome analysis demonstrated that a degree of Hp deglycosylation differs depending on the conditions used for N-glycan release and on the specific glycosylation site, with Asn 241 being the most resistant to deglycosylation under tested conditions. HILIC–UHPLC–FLR analysis enables robust quantification of 28 individual chromatographic peaks, in which N-glycan compositions were determined by UHPLC coupled to electrospray ionization quadrupole time of flight mass spectrometry. The developed analytical approach enables fast evaluation of total Hp N-glycosylation and is applicable in large-scale studies.  相似文献   
757.
This study focused on characterizing chemically and evaluating in vitro allelopathic and bioherbicidal potential of secondary metabolites extracted from the stem of Cuscuta campestris in seed germination, early seedling growth and early plant growth of Amaranthus retroflexus and Portulaca oleracea. The combined effects of stem extract and a reduced dose of herbicide metribuzin were also examined. Plant extract contained 17 phenolic compounds and the most abundant phenols were flavonoids: quercetin, (+)-catechin, daidzin, luteolin, and rutin. The seeds of P. oleracea were less sensitive than the seeds of A. retroflexus. The seed bioassay confirmed the inhibitory effect of stem extract on germination and early growth of both weed seedlings at concentrations of 0.75 % and 1 %, and a minor inhibitory effect in the plant bioassay. On the other hand, a synergy of C. campestris stem extract and metribuzin was revealed, as their combination achieved better results in the control of both weed species. Based on obtained data C. campestris stem extract could be a potential source of natural-based weed control molecules.  相似文献   
758.
In recent decades, there have been an increasing number of outbreaks of Ips typographus in Europe. A large amount of sanitary felling has taken place, with significant economic and ecological consequences. In order to anticipate such large-scale outbreaks, an effective monitoring system should be set up. One important aspect of monitoring is deciding which pheromone to use. Therefore, we decided to test five different commercially available pheromone lures under different disturbance conditions: Pheroprax®, IT Ecolure Extra®, Ipstyp®, Ipsowit® and Typosan®. We investigated the ability of the pheromones to distinguish between disturbed and undisturbed locations, their cost-efficiency ratio, and side effects such as bycatch abundance and composition. We set 50 traps in two areas with sites that were disturbed and undisturbed by windstorms. We collected the catch from traps every 1–2 weeks from the end of March until the end of September in 2019. We found that IT Ecolure Extra®, Ipsowit® and ® Pheroprax® caught the most I. typographus and best showed changes in the trap catch of I. typographus throughout the whole season. There was a low amount of bycatch (<6% of the total catch) and a low number of predators (a few specimens), but some groups seem to prefer certain pheromones. The cost of the pheromones increased with their effectiveness. However, pheromone costs are low relative to the personnel costs involved in setting traps and collecting the catch. Based on all of the gathered data, we created an index which helps to assess the cost-efficiency of the five chosen commercially available pheromones. We also present guidelines on how to make such an index to assist other researchers in choosing the right pheromone for monitoring populations of I. typographus or other bark beetle species.  相似文献   
759.
BackgroundPancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers, with around 9% of patients surviving >5 years. Asymptomatic in its initial stages, PDAC is mostly diagnosed late, when already a locally advanced or metastatic disease, as there are no useful biomarkers for detection in its early stages, when surgery can be curative. We have previously described a promising biomarker panel (LYVE1, REG1A, and TFF1) for earlier detection of PDAC in urine. Here, we aimed to establish the accuracy of an improved panel, including REG1B instead of REG1A, and an algorithm for data interpretation, the PancRISK score, in additional retrospectively collected urine specimens. We also assessed the complementarity of this panel with CA19-9 and explored the daily variation and stability of the biomarkers and their performance in common urinary tract cancers.Methods and findingsClinical specimens were obtained from multiple centres: Barts Pancreas Tissue Bank, University College London, University of Liverpool, Spanish National Cancer Research Center, Cambridge University Hospital, and University of Belgrade. The biomarker panel was assayed on 590 urine specimens: 183 control samples, 208 benign hepatobiliary disease samples (of which 119 were chronic pancreatitis), and 199 PDAC samples (102 stage I–II and 97 stage III–IV); 50.7% were from female individuals. PDAC samples were collected from patients before treatment. The samples were assayed using commercially available ELISAs. Statistical analyses were performed using non-parametric Kruskal–Wallis tests adjusted for multiple comparisons, and multiple logistic regression. Training and validation datasets for controls and PDAC samples were obtained after random division of the whole available dataset in a 1:1 ratio. The substitution of REG1A with REG1B enhanced the performance of the panel to detect resectable PDAC. In a comparison of controls and PDAC stage I–II samples, the areas under the receiver operating characteristic curve (AUCs) increased from 0.900 (95% CI 0.843–0.957) and 0.926 (95% CI 0.843–1.000) in the training (50% of the dataset) and validation sets, respectively, to 0.936 in both the training (95% CI 0.903–0.969) and the validation (95% CI 0.888–0.984) datasets for the new panel including REG1B. This improved panel showed both sensitivity (SN) and specificity (SP) to be >85%. Plasma CA19-9 enhanced the performance of this panel in discriminating PDAC I–II patients from controls, with AUC = 0.992 (95% CI 0.983–1.000), SN = 0.963 (95% CI 0.913–1.000), and SP = 0.967 (95% CI 0.924–1.000). We demonstrate that the biomarkers do not show significant daily variation, and that they are stable for up to 5 days at room temperature. The main limitation of our study is the low number of stage I–IIA PDAC samples (n = 27) and lack of samples from individuals with hereditary predisposition to PDAC, for which specimens collected from control individuals were used as a proxy.ConclusionsWe have successfully validated our urinary biomarker panel, which was improved by substituting REG1A with REG1B. At a pre-selected cutoff of >80% SN and SP for the affiliated PancRISK score, we demonstrate a clinically applicable risk stratification tool with a binary output for risk of developing PDAC (‘elevated’ or ‘normal’). PancRISK provides a step towards precision surveillance for PDAC patients, which we will test in a prospective clinical study, UroPanc.

Silvana Debernardi and colleagues establish a clinical risk score and a biomarker panel for early detection of pancreatic cancer.  相似文献   
760.
In a crowded environment, establishing interactions between different molecular partners can take a long time. Biological membranes have solved this issue, as they simultaneously are fluid and possess compartmentalized domains. This nanoscale organization of the membrane is often based on weak, local, and multivalent interactions between lipids and proteins. However, from local interactions at the nanoscale, different functional properties emerge at the higher scale, and these are critical to regulate and integrate cellular signaling. Rho of Plant (ROP) proteins are small guanosine triphosphate hydrolase enzymes (GTPases) involved in hormonal, biotic, and abiotic signaling, as well as fundamental cell biological properties such as polarity, vesicular trafficking, and cytoskeleton dynamics. Association with the membrane is essential for ROP function, as well as their precise targeting within micrometer-sized polar domains (i.e. microdomains) and nanometer-sized clusters (i.e. nanodomains). Here, we review our current knowledge about the formation and the maintenance of the ROP domains in membranes. Furthermore, we propose a model for ROP membrane targeting and discuss how the nanoscale organization of ROPs in membranes could determine signaling parameters like signal specificity, amplification, and integration.

The nanoscale organization of Rho of Plant proteins creates emergent properties that determine cellular signaling.  相似文献   
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