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Four drill cores and a clay pit section have been examined in the southern part of the Körös plain to understand the history and controls on alluvial sedimentation for the last ~ 40 ka. Four facies groups were identified, such as channel, channel margin, floodplain and floodbasin with seven distinctive facies. Magnetic susceptibility and mineralogy have further characterized the sedimentary facies indicating shifts in humidity conditions, variations in sediment flux and pedogenesis. Detailed pollen analysis of a 7.5 m thick clayey succession indicated climatic variability within the MIS 3 period. The spatial distribution of the different facies allowed outlining alluvial architecture of the study area. Three depositional units composed of various facies were identified based on OSL and radiocarbon data. These packages correspond to three major phases of channel activity: (F-I) pre-LGM period (> 30 ka to 24 ka), (F-II) post-LGM interstadial (18–16 ka), and (F-III) Late Glacial < 15 ka to ~ 10 ka). The pre-LGM and post-LGM “interstadial” phases are characterized by meandering river patterns, while the Late Glacial fluvial activity is characterized by a braided system in the area. Higher sediment supply feeding this braided river was probably caused by neotectonic uplift of the southern margin of the basin, documented by a significant stratigraphic gap between 25 and 14 ka.  相似文献   
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Chitosan, a versatile derivative of chitin, is widely used as an antimicrobial agent either alone or mixed with other natural polymers. Burkholderia cenocepacia is a multidrug-resistant bacteria and difficult to eradicate. Our previous studies shown that chitosan had strong antibacterial activity against B. cenocepacia. In the current study, we have investigated the molecular aspects for the susceptibility of B. cenocepacia in response to chitosan antibacterial activity. We have conducted RNA expression analysis of drug efflux system by RT-PCR, membrane protein profiling by SDS–PAGE, and by LC-MS/MS analysis following the validation of selected membrane proteins by real-time PCR analysis. By RT-PCR analysis, it was found that orf3, orf9, and orf13 were expressed at detectable levels, which were similar to control, while rest of the orf did not express. Moreover, shotgun proteomics analysis revealed 21 proteins in chitosan-treated cells and 16 proteins in control. Among them 4 proteins were detected as shared proteins under control and chitosan-treated cells and 17 proteins as uniquely identified proteins under chitosan-treated cells. Among the catalog of uniquely identified proteins, there were proteins involved in electron transport chain and ATP synthase, metabolism of carbohydrates and adaptation to atypical conditions proteins which indicate that utilization and pattern of chitosan is diverse which might be responsible for its antibacterial effects on bacteria. Moreover, our results showed that RND drug efflux system, which display the ability to transport a variety of structurally unrelated drugs from a cell and consequently are capable of conferring resistance to a diverse range of chemotherapeutic agents, was not determined to play its role in response to chitosan. It might be lipopolysaccharides interaction with chitosan resulted in the destabilization of membrane protein to membrane lyses to cell death. Membrane proteome analysis were also validated by RT-qPCR analysis, which corroborated our results that of membrane proteins.  相似文献   
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Scleroderma is the general disease of the connective tissue, which can be characterized by the proliferation of the connective tissue and fibrosis. According to the results of international studies scleroderma is frequently accompanied by neoplastic diseases, among which the most often occurring is the neoplastic pathology of the breast and the lungs. In May 2007, in the case of our 40-year-old woman patient the histological examination of the tumor we noticed in the left breast verified invasive carcinoma. In December 2007, after neoadjuvant chemotherapy she had a left mastectomy and then she was given postoperative irradiation, hormone therapy and trastuzumab (Herceptin) treatment, which was suspended in December 2008 due to oedema and fibrosis all over the body. In May 2009 she first visited the immunology outpatient department of our clinic, where we started her examination because of our suspicion of scleroderma and her cutaneous fibrosis symptoms, which was established on the basis of the examinations (immunoserology, body plethysmography, diffusing capacity of the lung for carbon monoxide, capillary microscopy, barium swallow) and her symptoms. She was given a conservative therapy (pentoxyphylline, amlodipine, nitroglycerin). Scleroderma arising after the neoplastic process of the breast is usually much more progressive than the primary disease. International reports also show a close correlation between breast cancer and the development of scleroderma, but its exact mechanism is not yet clear.  相似文献   
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One of the most promising applications for the restoration of small or moderately sized focal articular lesions is mosaicplasty (MP). Although recurrent hemarthrosis is a rare complication after MP, recently, various strategies have been designed to find an effective filling material to prevent postoperative bleeding from the donor site. The porous biodegradable polymer Polyactive (PA; a polyethylene glycol terephthalate - polybutylene terephthalate copolymer) represents a promising solution in this respect. A histological evaluation of the longterm PA-filled donor sites obtained from 10 experimental horses was performed. In this study, attention was primarily focused on the bone tissue developed in the plug. A computer-assisted image analysis and quantitative polarized light microscopic measurements of decalcified, longitudinally sectioned, dimethylmethylene blue (DMMB)- and picrosirius red (PS) stained sections revealed that the coverage area of the bone trabecules in the PA-filled donor tunnels was substantially (25%) enlarged compared to the neighboring cancellous bone. For this quantification, identical ROIs (regions of interest) were used and compared. The birefringence retardation values were also measured with a polarized light microscope using monochromatic light. Identical retardation values could be recorded from the bone trabeculae developed in the PA and in the neighboring bone, which indicates that the collagen orientation pattern does not differ significantly among these bone trabecules. Based on our new data, we speculate that PA promotes bone formation, and some of the currently identified degradation products of PA may enhance osteo-conduction and osteoinduction inside the donor canal.  相似文献   
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The phototransformation pathways of protochlorophyllide forms were studied in 8?C14-day-old leaves of dark-germinated wheat (Triticum aestivum L.) using white, 632.8?nm He?CNe laser and 654?nm laser diode light. The photon flux density (PFD) values (0.75?C360???mol photons?m?2?s?1), the illumination periods (20?ms?C10?s) and the temperature of the leaves (between ?60?°C and room temperature) were varied. The 77?K fluorescence spectra of partially phototransformed leaves showed gradual accumulation or even the dominance of the 675?nm emitting chlorophyllide or chlorophyll form at room temperature with 632.8?nm of PFD less than 200???mol photons?m?2?s?1 or with 654?nm of low PFD (7.5???mol photons?m?2?s?1) up to 1?s. Longer wavelength (685 or 690?nm) emitting chlorophyllide forms appeared at illuminations under ?25?°C with both laser lights or at room temperature when the PFD values were higher or the illumination period was longer than above. We concluded that the formation of the 675?nm emitting chlorophyllide form does not indicate the direct photoactivity of the 633?nm emitting protochlorophyllide form; it can derive from 644 and 657?nm forms via instantaneous disaggregation of the newly-produced chlorophyllide complexes. The disaggregation is strongly influenced by the molecular environment and the localization of the complex.  相似文献   
18.
Clinical studies have suggested that long-term nitrate treatment does not improve and may even worsen cardiovascular mortality, and the possible role of nitrate tolerance has been suspected. Nitrate tolerance has been recently shown to increase vascular superoxide and peroxynitrite production leading to vascular dysfunction. Nevertheless, nitrates exert direct cardiac effects independent from their vascular actions. Therefore, we investigated whether in vivo nitroglycerin treatment leading to vascular nitrate tolerance increases cardiac formation of nitric oxide (NO), reactive oxygen species, and peroxynitrite, thereby leading to cardiac dysfunction. Nitrate tolerance increased bioavailability of NO in the heart without increasing formation of reactive oxygen species. Despite elevated myocardial NO, neither cardiac markers of peroxynitrite formation nor cardiac mechanical function were affected by nitroglycerin treatment. However, serum free nitrotyrosine, a marker for systemic peroxynitrite formation, was significantly elevated in nitroglycerin-treated animals. This is the first demonstration that, although the systemic effects of nitroglycerin may be deleterious due to enhancement of extracardiac peroxynitrite formation, nitroglycerin does not result in oxidative damage in the heart.  相似文献   
19.
Eighteen mycoparasitic Trichoderma strains were tested for their ability to degrade heat-inactivated Bacillus cereus var. mycoides, B. megaterium, B. subtilis, Escherichia coli, Micrococcus luteus, Pseudomonas aeruginosa and Serratia marcescens cells. The non-inductive and inductive ferment broths of five strains with good degrading abilities towards B. subtilis were investigated for specific degrading enzyme activities. In addition to trypsin- and chymotrypsin-like protease activities, -1,4-N-acetyl-glucosaminidase (NAGase) was also secreted. Strain Trichoderma harzianum T19 had the most outstanding degrading abilities. The extracellular degrading enzymes of this strain were separated on a Sephadex G-150 column, and their preliminary characterization was performed. The results demonstrated that muramidase-like activities are present in the ferment broth of this T. harzianum strain.  相似文献   
20.
Comorbid depression of Alzheimer's disease (AD) is a common mood disorder in the elderly and a broad spectrum of antidepressants have been used for its treatment. Abeta peptides and other derivatives of the amyloid precursor protein (APP) have been implicated as central to the pathogenesis of AD. However, the functional relationship of APP and its proteolytic derivatives to antidepressant therapy is not known. In this study, Western blotting was used to test the ability of the tricyclic antidepressant (TCA) imipramine or the selective serotonin reuptake inhibitor (SSRI) citalopram to change the release of APP and the protein kinase C (PKC) content. Both antidepressants increased APP secretion in primary rat neuronal cultures. Imipramine or citalopram enhanced the level of secreted APP by 3.2- or 3.4-fold, respectively. Increases in PKC level were observed only after imipramine treatment. These in vitro data suggest that both TCA and SSRI are able to interfere with the APP metabolism. Imipramine promotes the non-amyloidogenic route of APP processing via stimulatory effects on PKC. We propose that PKC is not involved in the mechanism underlying the effects of citalopram on the APP metabolism. Since the secreted APP is not further available for the pathological cleavage of beta- and gamma-secretases, antidepressant medication might be beneficial in AD therapy.  相似文献   
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