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81.
Moldvay J 《Magyar onkologia》2000,44(3):195-202
Primary bronchial cancer is the most common cause of cancer death worldwide, and it shows a steadily increasing incidence. Beside classical histological typing and grading, immunohistochemical, cytometric, and molecular biological parameters are highly needed to assist light microscopy investigations to better characterize primary bronchial cancers. In this work the author summarizes the main tumor markers and prognostic factors in lung cancer studied intensively at present. Serum markers as well as different tissue markers, such as cell proliferation markers, oncogenes, growth factors, apoptosis markers and vascularisation markers, tumor suppressor genes and markers of drug resistance are discussed in details. The methods currently used in this field are also mentioned and the data of the literature is often completed with results of the author's own investigations. An overview is given about the role of tumor markers in the early detection of lung cancer, in the assessment of tumor aggressiveness, and in therapy of lung cancer. The aim of this work is to create a bridge between the research laboratory in which lung cancer is studied sometimes using very sophisticated techniques and the bedside with all its practical, difficult but very important questions. Getting closer the theory and the practice can be very promising in the establishment of a fruitful collaboration in order to be more effective in the fight against lung cancer. 相似文献
82.
Christian Schobert Lucian Baker Judit Szederkényi Pia Großmann Ewald Komor Hiroaki Hayashi Mitsuo Chino William J. Lucas 《Planta》1998,206(2):245-252
The mature, functional sieve-tube system in higher plants is dependent upon protein import from the companion cells to maintain
a functional long-distance transport system. Soluble proteins present within the sieve-tube lumen were investigated by analysis
of sieve-tube exudates which revealed the presence of distinct sets of polypeptides in seven monocotyledonous and dicotyledonous
plant species. Antibodies directed against sieve-tube exudate proteins from Ricinus communis L. demonstrated the presence of shared antigens in the phloem sap collected from Triticum aestivum L., Oryza sativa L., Yucca filamentosa L., Cucurbita maxima Duch., Robinia pseudoacacia L. and Tilia platyphyllos L. Specific antibodies were employed to identify major polypeptides. Molecular chaperones related to Rubisco-subunit-binding
protein and cyclophilin, as well as ubiquitin and the redox proteins, thioredoxin h and glutaredoxin, were detected in the
sieve-tube exudate of all species examined. Actin and profilin, a modulator of actin polymerization, were also present in
all analyzed phloem exudates. However, some proteins were highly species-specific, e.g. cystatin, a protease-inhibitor was
present in R. communis but was not detected in exudates from other species, and orthologs of the well-known squash phloem lectin, phloem protein
2, were only identified in the sieve-tube exudate of R. communis and R. pseudoacacia. These findings are discussed in terms of the likely roles played by phloem proteins in the maintenance and function of the
enucleate sieve-tube system of higher plants.
Received: 12 February 1998 / Accepted: 16 March 1998 相似文献
83.
Gabriella Juhasz Xenia Gonda Gabor Hullam Nora Eszlari David Kovacs Judit Lazary Dorottya Pap Peter Petschner Rebecca Elliott John Francis William Deakin Ian Muir Anderson Peter Antal Klaus-Peter Lesch Gyorgy Bagdy 《PloS one》2015,10(3)
Background
Although 5-HTTLPR has been shown to influence the risk of life stress-induced depression in the majority of studies, others have produced contradictory results, possibly due to weak effects and/or sample heterogeneity.Methods
In the present study we investigated how age, type and intensity of life-stressors modulate the effect of 5-HTTLPR on depression and anxiety in a European population cohort of over 2300 subjects. Recent negative life events (RLE), childhood adversity (CHA), lifetime depression, Brief Symptoms Inventory (BSI) depression and anxiety scores were determined in each subject. Besides traditional statistical analysis we calculated Bayesian effect strength and relevance of 5-HTTLPR genotypes in specified models.Results
The short (s) low expressing allele showed association with increased risk of depression related phenotypes, but all nominally significant effects would turn to non-significant after correction for multiple testing in the traditional analysis. Bayesian effect strength and relevance analysis, however, confirmed the role of 5-HTTLPR. Regarding current (BSI) and lifetime depression 5-HTTLPR-by-RLE interactions were confirmed. Main effect, with other words direct association, was supported with BSI anxiety. With more frequent RLE the prevalence or symptoms of depression increased in ss carriers. Although CHA failed to show an interaction with 5-HTTLPR, in young subjects CHA sensitized towards the depression promoting effect of even mild RLE. Furthermore, the direct association of anxiety with the s allele was driven by young (≤30) individuals.Limitations
Our study is cross-sectional and applies self-report questionnaires.Conclusions
Albeit 5-HTTLPR has only weak/moderate effects, the s allele is directly associated with anxiety and modulates development of depression in homogeneous subgroups. 相似文献84.
Arsenic Exposure Increases Monocyte Adhesion to the Vascular Endothelium,a Pro-Atherogenic Mechanism
Maryse Lemaire Luis Fernando Negro Silva Catherine A. Lemarié Alicia M. Bolt Manuel Flores Molina Regina M. Krohn Judit E. Smits Stéphanie Lehoux Koren K. Mann 《PloS one》2015,10(9)
Epidemiological studies have shown that arsenic exposure increases atherosclerosis, but the mechanisms underlying this relationship are unknown. Monocytes, macrophages and platelets play an important role in the initiation of atherosclerosis. Circulating monocytes and macrophages bind to the activated vascular endothelium and migrate into the sub-endothelium, where they become lipid-laden foam cells. This process can be facilitated by platelets, which favour monocyte recruitment to the lesion. Thus, we assessed the effects of low-to-moderate arsenic exposure on monocyte adhesion to endothelial cells, platelet activation and platelet-monocyte interactions. We observed that arsenic induces human monocyte adhesion to endothelial cells in vitro. These findings were confirmed ex vivo using a murine organ culture system at concentrations as low as 10 ppb. We found that both cell types need to be exposed to arsenic to maximize monocyte adhesion to the endothelium. This adhesion process is specific to monocyte/endothelium interactions. Hence, no effect of arsenic on platelet activation or platelet/leukocyte interaction was observed. We found that arsenic increases adhesion of mononuclear cells via increased CD29 binding to VCAM-1, an adhesion molecule found on activated endothelial cells. Similar results were observed in vivo, where arsenic-exposed mice exhibit increased VCAM-1 expression on endothelial cells and increased CD29 on circulating monocytes. Interestingly, expression of adhesion molecules and increased binding can be inhibited by antioxidants in vitro and in vivo. Together, these data suggest that arsenic might enhance atherosclerosis by increasing monocyte adhesion to endothelial cells, a process that is inhibited by antioxidants. 相似文献
85.
Shu Chang Judit Berman Yanmin Sheng Yingdian Wang Teresa Capell Lianxuan Shi Xiuzhen Ni Gerhard Sandmann Paul Christou Changfu Zhu 《PloS one》2015,10(6)
The assignment of functions to genes in the carotenoid biosynthesis pathway is necessary to understand how the pathway is regulated and to obtain the basic information required for metabolic engineering. Few carotenoid ε-hydroxylases have been functionally characterized in plants although this would provide insight into the hydroxylation steps in the pathway. We therefore isolated mRNA from the endosperm of maize (Zea mays L., inbred line B73) and cloned a full-length cDNA encoding CYP97C19, a putative heme-containing carotenoid ε hydroxylase and member of the cytochrome P450 family. The corresponding CYP97C19 genomic locus on chromosome 1 was found to comprise a single-copy gene with nine introns. We expressed CYP97C19 cDNA under the control of the constitutive CaMV 35S promoter in the Arabidopsis thaliana lut1 knockout mutant, which lacks a functional CYP97C1 (LUT1) gene. The analysis of carotenoid levels and composition showed that lutein accumulated to high levels in the rosette leaves of the transgenic lines but not in the untransformed lut1 mutants. These results allowed the unambiguous functional annotation of maize CYP97C19 as an enzyme with strong zeinoxanthin ε-ring hydroxylation activity. 相似文献
86.
Bánóczi Z Gorka-Kereskényi Á Reményi J Orbán E Hazai L Tökési N Oláh J Ovádi J Béni Z Háda V Szántay C Hudecz F Kalaus G Szántay C 《Bioconjugate chemistry》2010,21(11):1948-1955
Vinblastine is a widely used anticancer drug with undesired side effects. Its conjugation with carrier molecules could be an efficient strategy to reduce these side effects. Besides this, the conjugate could exhibit increased efficiency against resistant cells, e.g., due to the altered internalization pathway. Oligoarginines, as cell-penetrating peptides, can transport covalently attached compounds into different kinds of cells and enhance the efficiency of those compounds. We report here the coupling of vinblastine through its carboxyl group at position 16 with the N-terminal amino function of L-Trp methyl ester. After hydrolysis of the ester group, 17-desacetylvinblastineTrp was conjugated to the N-terminal amino group of oligoarginine via the C-terminal carboxyl group of the Trp moiety in solution. The antitumor effect of conjugates was studied on sensitive and resistant human leukemia (HL-60) cells in vitro. Our data suggest that all conjugates investigated possess an antiproliferative effect against the studied cells. However, the effect was dependent on the number of Arg residues in the conjugates: Arg? > Arg? ? Arg?. The conjugate with Arg? exhibited similar efficicacy as compared with free 17-desacetylvinblastineTrp. The in vitro studies also showed that the tubulin binding ability of vinblastine was essentially preserved even in the octaarginine conjugate. We also observed that two isomers were formed during conjugation. These isomers showed different levels of activity against tubulin polymerization in vitro and in vivo. The 17-desacetylvinblastineTrp-Arg?-1 isomer conjugate possessed high selectivity against the mitotic spindles. HRMS and NMR data suggest that 17-desacetylvinblastineTrp-Arg?-1 and 17-desacetylvinblastineTrp-Arg?-2 are epimers at the tryptophan α carbon atom. 相似文献
87.
Neus Teixid��-Travesa Judit Vill��n Cristina Lacasa Maria Teresa Bertran Marco Archinti Steven P. Gygi Carme Caelles Joan Roig Jens L��ders 《Molecular biology of the cell》2010,21(22):3963-3972
The γ-tubulin complex is a multi-subunit protein complex that nucleates microtubule polymerization. γ-Tubulin complexes are present in all eukaryotes, but size and subunit composition vary. In Drosophila, Xenopus, and humans large γ-tubulin ring complexes (γTuRCs) have been described, which have a characteristic open ring-shaped structure and are composed of a similar set of subunits, named γ-tubulin, GCPs 2-6, and GCP-WD in humans. Despite the identification of these proteins, γTuRC function and regulation remain poorly understood. Here we establish a new method for the purification of native human γTuRC. Using mass spectrometry of whole protein mixtures we compared the composition of γTuRCs from nonsynchronized and mitotic human cells. Based on our analysis we can define core subunits as well as more transient interactors such as the augmin complex, which associates specifically with mitotic γTuRCs. We also identified GCP8/MOZART2 as a novel core subunit that is present in both interphase and mitotic γTuRCs. GCP8 depletion does not affect γTuRC assembly but interferes with γTuRC recruitment and microtubule nucleation at interphase centrosomes without disrupting general centrosome structure. GCP8-depleted cells do not display any obvious mitotic defects, suggesting that GCP8 specifically affects the organization of the interphase microtubule network. 相似文献
88.
Yésica García‐Ramos Marta Paradís‐Bas Judit Tulla‐Puche Fernando Albericio 《Journal of peptide science》2010,16(12):675-678
CM resin is a totally PEG‐based resin, made exclusively from primary ether bonds and therefore highly chemically stable. Compared to other PEG resins, it exhibits good loading and is user friendly because of its free‐flowing form upon drying. It shows improved performance over PS resins for the preparation of hydrophobic, highly structured poly‐Arg peptides. In combination with ψPros, it allows the synthesis of small proteins such as the chemokine RANTES. Like other PEG‐based resins, CM resin swells well in biocompatible solvents such as water, thereby allowing on‐bead screening. Furthermore, the high loading of this resin permits the use of a tiny quarter of a bead as a microreactor for HPLC and MALDI‐TOF analysis, thus further extending its applications in the field of combinatorial chemistry. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
89.
F2-isoprostanes are useful biomarkers of oxidative status in humans. We developed an ultraperformance liquid chromatography-tandem mass spectrometric (UPLC-MS/MS) method to quantify 2,3-dinor-8-iso prostaglandin F2α, a urinary metabolite of 8-iso-prostaglandin F2α. Urine was purified by solid-phase extraction and analyzed by UPLC-MS/MS with negative-ion electrospray ionization. The method was robust with a mean inaccuracy of 9%, interday and intraday imprecision of 7.5% or lower, and a lower limit of quantification of 0.5 μg/L, equivalent to 0.04 pmol injected onto the column. An analysis time of 6 min was shorter than previously published methods and amenable to large studies. 相似文献
90.
Nikolett Kállai Oliver Luhn Judit Dredán Kristóf Kovács Miléna Lengyel István Antal 《AAPS PharmSciTech》2010,11(1):383-391
The objective of the present study was to investigate the effect of the pellet core materials isomalt, sugar, and microcrystalline cellulose on the in vitro drug release kinetics of coated sustained-release pellets as well as to evaluate the influence of different ratios of polymethacrylate copolymers exhibiting different permeability characteristics on the drug release rate. For characterization of the drug release process of pellets, the effect of osmolality was studied using glucose as an osmotically active agent in the dissolution medium. The pellet cores were layered with diclofenac sodium as model drug and coated with different ratios of Eudragit® RS30D and Eudragit® RL30D (ERS and ERL; 0:1 and 0.5:0.5 and 1:0 ratio) in a fluid bed apparatus. Physical characteristics such as mechanical strength, shape, and size proved that the inert cores were adequate for further processing. The in vitro dissolution tests were performed using a USP Apparatus I (basket method). The results demonstrated that, besides the ratio of the coating polymers (ERS/ERL), the release mechanism was also influenced by the type of starter core used. Sugar- and isomalt-type pellet cores demonstrated similar drug release profiles. 相似文献