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The extent of phenotypic variation of St. John's wort (Hypericum perforatum L.) plants transformed with wild agropine ATCC 15834 Agrobacterium rhizogenes plasmid was evaluated with respect to the number of rol genes integrations. The transfer of T(L)-DNA to plant explants during each transformation event was incomplete with different rolA, rolB, and rolC copy numbers. Along with typical features representing the hairy root syndrome, an altered size, number and density of dark and translucent glands, changes in ability to synthesize secondary metabolites, and reduced fertility were observed. The highest copy number of transferred rol genes resulted in weak expression of transgenic character and comparable quantitative parameters with the controls. Only 1 out of 11 transgenic clones was able to produce seed progeny and not more than 4 out of its 35 offsprings were positive for rolC gene integration. Sterility of the clones was due to retarded development of both gametophytes.  相似文献   
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* The 'in planta' visualization of F-actin in all cells and in all developmental stages of a plant is a challenging problem. By using the soybean heat inducible Gmhsp17.3B promoter instead of a constitutive promoter, we have been able to label all cells in various developmental stages of the moss Physcomitrella patens, through a precise temperature tuning of the expression of green fluorescent protein (GFP)-talin. * A short moderate heat treatment was sufficient to induce proper labeling of the actin cytoskeleton and to allow the visualization of time-dependent organization of F-actin structures without impairment of cell viability. * In growing moss cells, dense converging arrays of F-actin structures were present at the growing tips of protonema cell, and at the localization of branching. Protonema and leaf cells contained a network of thick actin cables; during de-differentiation of leaf cells into new protonema filaments, the thick bundled actin network disappeared, and a new highly polarized F-actin network formed. * The controlled expression of GFP-talin through an inducible promoter improves significantly the 'in planta' imaging of actin.  相似文献   
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DNase I inhibitory potential of water extract of nine Hypericum species (H. umbellatum, H. barbatum, H. rumeliacum, H. rochelii, H. perforatum, H. tetrapterum, H. olympicum, H. hirsutum, H. linarioides) and the most important Hypericum secondary metabolites (hypericin, hyperforin, quercetin, and rutin) was investigated. All examined Hypericum extracts inhibited DNase I with IC50 below 800 μg/ml, whereby H. perforatum was the most potent (IC50=391.26±68.40 μg/ml). Among the investigated Hypericum secondary metabolites, rutin inhibited bovine pancreatic DNase I in a non‐competitive manner with IC50 value of 108.90±9.73 μm . DNase I inhibitory ability of rutin was further confirmed on DNase I in rat liver homogenate (IC50=137.17±16.65 μm ). Due to the involvement of DNase I in apoptotic processes the results of this study indicate the importance of frequent rutin and H. perforatum consumption in daily human nutrition. Rutin is a dietary component that can contribute to male infertility prevention by showing dual mechanism of sperm DNA protection, DNase I inhibition and antioxidant activity.  相似文献   
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Land plants need precise thermosensors to timely establish molecular defenses in anticipation of upcoming noxious heat waves. The plasma membrane-embedded cyclic nucleotide-gated Ca2+ channels (CNGCs) can translate mild variations of membrane fluidity into an effective heat shock response, leading to the accumulation of heat shock proteins (HSP) that prevent heat damages in labile proteins and membranes. Here, we deleted by targeted mutagenesis the CNGCd gene in two Physcomitrella patens transgenic moss lines containing either the heat-inducible HSP-GUS reporter cassette or the constitutive UBI-Aequorin cassette. The stable CNGCd knockout mutation caused a hyper-thermosensitive moss phenotype, in which the heat-induced entry of apoplastic Ca2+ and the cytosolic accumulation of GUS were triggered at lower temperatures than in wild type. The combined effects of an artificial membrane fluidizer and elevated temperatures suggested that the gene products of CNGCd and CNGCb are paralogous subunits of Ca2+channels acting as a sensitive proteolipid thermocouple. Depending on the rate of temperature increase, the duration and intensity of the heat priming preconditions, terrestrial plants may thus acquire an array of HSP-based thermotolerance mechanisms against upcoming, otherwise lethal, extreme heat waves.  相似文献   
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Role of various cytokines have been implicated in the development and perpetuation of Sjogren's syndrome (SS), but no specific cytokine could be determined as a major contributor to the SS. Salivary and serum interleukin 6 (IL-6) levels have been studied previously in patients with SS, but data upon salivary and serum basic fibroblast growth factor (bFGF) in SS are lacking. The aim of this study was to evaluate levels of salivary and serum IL-6 and bFGF in 18 patients with SS, age range 32-79, mean 54.05 years. Control group consisted of 23 healthy participants, mean age 25 years. Serum IL-6 and bFGF levels were not significantly different between patients with SS and healthy controls. Elevated levels of salivary IL-6 and bFGF in patients with SS when compared to the healthy controls were found (p<0.001). We might speculate that higher levels of salivary IL-6 and bFGF in patients with SS might originate from local production probably having source in the salivary glands.  相似文献   
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Among the large family of cyclodepsipeptides, the simplest members are the cyclodidepsipeptides which have an ester group and an amide group in the same six-membered ring. To point out the pharmacological potential of this class of compounds, the present article reviews structure, isolation, synthesis and biological properties of the known cyclodidepsipeptides. Synthesis of cyclodidepsipeptides is achieved by two general approaches—by initial formation of the amide bond, or initial formation of the ester bond; and subsequent intermolecular cyclization to cyclodidepsipeptide structure. It is closely related to the condensation and ring-closure strategies applied in the preparation of the larger members of the cyclodepsipeptide family. However, due to synthesis of the smaller heretocycles it allows for the use of more versatile building blocks. There are data on antimicrobial, antioxidant and immunomodulatory activities of cyclodidepsipeptides as well as their inhibitory activities toward α-glucosidase, acyl-CoA:cholesterol acyltransferase, xanthine oxidase and platelet aggregation. Because we have recently found that two 6-(propan-2-yl)-4-methyl-morpholine-2,5-diones, as novel non-purine xanthine oxidase inhibitors, may give promise to be used in the treatment of gout, in this review we have included a study of molecular interactions of the selected cyclodidepsipeptides with xanthine oxidase using idTarget web server. Cyclodidepsipeptides showed promising pharmacological activities and meet all criteria for good solubility and permeability. However, further research of their medical application is necessary. In addition to this, the diversity of natural cyclodidepsipeptides, simplicity for synthesis and convenience for rational drug design indicate the cyclodidepsipeptide as promising scaffold in medicinal chemistry.  相似文献   
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The goal of this study was to compare the possibilities and limitations of direct digital radiography of the chest (DDR), the use of ultrasound of the chest (US) and single slice computed tomography of the chest (CT) in diagnosing pleural mesothelioma. The study was conducted during the course of one year, on 80 patients who were successively referred to a specialized institution, under clinical suspicion of mesothelioma. The method of investigation was the comparison of findings, obtained by the reviewed methods of examination, with the pathohistologic results of a biopsy performed on each patient. The findings that were obtained by the enumerated methods were classified according to the radiologic signs that were found in each individual patient. We evaluated following radiological findings (signs), on each of the investigated methods: plaques, localized and generalized pleural thickenings, calcifications of the pleura, pleural effusions, parapneumonic effusions, pleural empyema, (round) atelectasis, pneumothorax, tumor mass or node, inflammatory infiltrate, elevation of the hemidiaphragm and osteolysis. The results of these were compared with pathohistologic findings and analyzed by means of standard statistical methods. The highest sensitivity was found for CT (94.4%), followed by US (92.6%), and by DDR (90.7%). The highest specificity was obtained with DDR (46.2%), followed by CT (35.5%) and US (23.8%). The comparison of these methods showed 90% diagnostic accuracy for DDR in relation to CT CT as an individual method best satisfied most of the criteria for diagnosing mesothelioma. No pathognomonic radiologic sign for mesothelioma was found.  相似文献   
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