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91.
Cuperlovic-Culf M Ferguson D Culf A Morin P Touaibia M 《The Journal of biological chemistry》2012,287(24):20164-20175
Glioblastoma multiforme (GBM) is the most common form of malignant glioma, characterized by unpredictable clinical behaviors that suggest distinct molecular subtypes. With the tumor metabolic phenotype being one of the hallmarks of cancer, we have set upon to investigate whether GBMs show differences in their metabolic profiles. (1)H NMR analysis was performed on metabolite extracts from a selection of nine glioblastoma cell lines. Analysis was performed directly on spectral data and on relative concentrations of metabolites obtained from spectra using a multivariate regression method developed in this work. Both qualitative and quantitative sample clustering have shown that cell lines can be divided into four groups for which the most significantly different metabolites have been determined. Analysis shows that some of the major cancer metabolic markers (such as choline, lactate, and glutamine) have significantly dissimilar concentrations in different GBM groups. The obtained lists of metabolic markers for subgroups were correlated with gene expression data for the same cell lines. Metabolic analysis generally agrees with gene expression measurements, and in several cases, we have shown in detail how the metabolic results can be correlated with the analysis of gene expression. Combined gene expression and metabolomics analysis have shown differential expression of transporters of metabolic markers in these cells as well as some of the major metabolic pathways leading to accumulation of metabolites. Obtained lists of marker metabolites can be leveraged for subtype determination in glioblastomas. 相似文献
92.
Stem cell-based therapy is emerging as a novel approach for myocardial repair over conventional cardiovascular therapies. In addition to embryonic stem cells and adult stem cells from noncardiac sources, there is a small population of resident stem cells in the heart from which new cardiac cells (myocytes, vascular endothelial cells and smooth muscle cells) can be derived and used for cardiac repair in case of heart injury. It has been proposed that the clinical benefit of stem cells may arise from secreted proteins that mediate regeneration in a paracrine/autocrine manner. To be able to track the regulatory pathway on a molecular basis, utilization of proteomics in stem cell research is essential. Proteomics offers a tool that can address questions regarding stem cell response to disease/injury. 相似文献
93.
Marek Vaculík Alexander Lux Miroslava Luxová Eiichi Tanimoto Irene Lichtscheidl 《Environmental and Experimental Botany》2009,67(1):52-58
The influence of silicon on the growth of maize plants cultivated in hydroponics in the presence of cadmium (5 μM) was investigated. Four different treatments were used: Control (C), Cadmium (Cd), Silicon (Si) and Cadmium plus Silicon (Cd + Si). The Si concentration was 35 mM. Thirteen-day-old plants were harvested. Growth parameters (length of primary seminal root, leaf area of first and second fully developed leaves, fresh and dry weight of below- and above-ground parts of the plants), and Cd concentration and total amount of Cd in the below- and above-ground parts were determined. In roots, the development of the endodermal barrier was observed by fluorescent staining with Fluorol yellow 088.Inhibitory effects of Cd on plant growth were observed. Silicon treatment in the absence of Cd had positive effects on most of observed growth parameters compared with the control. Moreover, Si in the Cd + Si treatment improved all growth parameters compared with the cadmium treatment. Silicon increased the cell-wall extensibility both in Si and Cd + Si treatments when compared with the control. Alleviation of the Cd-inhibitory effect on maize plants by Si was not due to exclusion of Cd from the plant; in contrast, Cd concentration in below- and above-ground plant parts and the total amount of Cd per plant were significantly higher in the Cd + Si plants than in the Cd treatment. The increased Cd content in Cd + Si plants was correlated with the development of the endodermis; during the second stage of endodermal development, suberin lamellae were formed at a greater distance from the root apex in the Cd + Si than in the Cd treatment. Silicon itself did not influence the development of suberin lamellae in the maize roots compared with the control. 相似文献
94.
Tajana Filipec Kanizaj Miroslava Katicic Bruno Skurla Mirjana Ticak Vanda Plecko Smilja Kalenic 《Helicobacter》2009,14(1):29-35
Background: The study compares the eradication success of standard first-line triple therapies of different durations (7, 10, and 14 days).
Materials and Methods: A total of 592 naive Helicobacter pylori -positive patients were randomized to receive pantoprazole, amoxicillin, and clarithromycin or metronidazole for 14 days (PACl14 or PAM14), 10 days (PACl10 or PAM10), or 7 days (PACl7 or PAM7). H. pylori eradication was assessed by histological, microbiological, and rapid urease examination.
Results: The intention-to-treat (ITT) and per-protocol (PP) analyses have shown no overall statistically significant differences between the eradication success of PACl and PAM treatment groups (ITT p = .308, PP p = .167). Longer treatment duration has yielded statistically significant increase in eradication success for clarithromycin (ITT p = .004; PP p = .004) and metronidazole (ITT p = .010; PP p = .034) based regimens. Namely, PACl10, PACl14, and PAM14 protocols resulted in eradication success exceeding 80% in ITT and 90% in PP analysis. Primary resistance to clarithromycin and metronidazole equals 8.2% and 32.9%, respectively. Prolonging the metronidazole-based treatment duration in patients with resistant strains resulted in statistically significant higher eradication success.
Conclusions: For all antimicrobial combinations, 14 days protocols have led to a significant increase of H. pylori eradication success when compared to 10 and 7 days, respectively. Prolonging the treatment duration can overcome the negative effect of metronidazole resistance. Only PAM14, PACl10 protocols achieved ITT success > 80% and should be recommended as the first line eradication treatment in Croatia. 相似文献
Materials and Methods: A total of 592 naive Helicobacter pylori -positive patients were randomized to receive pantoprazole, amoxicillin, and clarithromycin or metronidazole for 14 days (PACl14 or PAM14), 10 days (PACl10 or PAM10), or 7 days (PACl7 or PAM7). H. pylori eradication was assessed by histological, microbiological, and rapid urease examination.
Results: The intention-to-treat (ITT) and per-protocol (PP) analyses have shown no overall statistically significant differences between the eradication success of PACl and PAM treatment groups (ITT p = .308, PP p = .167). Longer treatment duration has yielded statistically significant increase in eradication success for clarithromycin (ITT p = .004; PP p = .004) and metronidazole (ITT p = .010; PP p = .034) based regimens. Namely, PACl10, PACl14, and PAM14 protocols resulted in eradication success exceeding 80% in ITT and 90% in PP analysis. Primary resistance to clarithromycin and metronidazole equals 8.2% and 32.9%, respectively. Prolonging the metronidazole-based treatment duration in patients with resistant strains resulted in statistically significant higher eradication success.
Conclusions: For all antimicrobial combinations, 14 days protocols have led to a significant increase of H. pylori eradication success when compared to 10 and 7 days, respectively. Prolonging the treatment duration can overcome the negative effect of metronidazole resistance. Only PAM14, PACl10 protocols achieved ITT success > 80% and should be recommended as the first line eradication treatment in Croatia. 相似文献
95.
Marcin Woźniak Boris Malyarchuk Miroslava Derenko Tomas Vanecek Jan Lazur Pavol Gomolcak Tomasz Grzybowski 《American journal of physical anthropology》2010,142(4):540-548
Analysis of Y chromosome Y‐STRs has proven to be a useful tool in the field of population genetics, especially in the case of closely related populations. We collected DNA samples from 169 males of Czech origin, 80 males of Slovakian origin, and 142 males dwelling Northern Poland. We performed Y‐STR analysis of 12 loci in the samples collected (PowerPlex Y system from Promega) and compared the Y chromosome haplotype frequencies between the populations investigated. Also, we used Y‐STR data available from the literature for comparison purposes. We observed significant differences between Y chromosome pools of Czechs and Slovaks compared to other Slavic and European populations. At the same time we were able to point to a specific group of Y‐STR haplotypes belonging to an R1a haplogroup that seems to be shared by Slavic populations dwelling in Central Europe. The observed Y chromosome diversity may be explained by taking into consideration archeological and historical data regarding early Slav migrations. Am J Phys Anthropol 142:540–548, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
96.
Ivan Vučković Vlatka Vajs Miroslava Stanković Vele Tešević Slobodan Milosavljević 《化学与生物多样性》2010,7(3):698-704
A new prenylated flavanonol named seselinonol ( 1 ) was isolated from the roots of Seseli annuum, together with the well‐known biologically active polyacetylenes falcarinol ( 2 ) and falcarindiol ( 3 ), and the prenylated furanocoumarin phellopterin ( 4 ). Its structure was elucidated by extensive spectroscopic analysis, including HR‐ESI‐MS, 1D‐ and 2D‐NMR. Seselinonol and phellopterin were tested for in vitro protective effect on chromosome aberrations in peripheral human lymphocytes using cytochalasin‐B blocked micronucleus (CBMN) assay. The new compound exerted a beneficial effect by decreasing DNA damage of human lymphocytes. 相似文献
97.
Blomaee accumulation, leaf longevity and growth rate of two spring forest geophytes, Scllla blfolla L. and Arum maculatum L. were estimated separately for three size groups within each population of these species. Despite the differences in leaf longevity, both species showed a similar pattern of blomass accumulation In relation to their phenologles and reproductive demands. Eco-physlological acclimation to changing light environment was assumed through photosynthetic parameters and dynamics of leaf area Index In the predominant size group of each species. A light response curve was measured under natural light for each species through the continuum of Its phenology to quantify the photosynthetic photon flux density at light saturation, light-saturated photosynthetic rate, light compensation point, and dark respiration. Light-saturated assimilation per leaf area basis, dark respiration rate and light compensation points were significantly higher in S. blfolla relative to A. maculatum. However, the acclimation of photosynthesis that would respond to light changes in environment was not found in S. bifolla. In contrast, In A. maculatum a marked shift In the light dependence of photosynthesis through the season was noticed, which resulted In a strong photosynthetic acclimation to the low-light conditions. Accompanied by significant leaf area Index, this efficient low-light photosynthesis enabled greater leaf longevity, and consequently longer accumulative period to A. maculatum. From the different parameters that we determined (both photosynthetic acclimation and growth strategy) it would appear that these species belong to two distinct subgroups: S. blfolla to the early and A. maculatum to the late vernals. 相似文献
98.
Marjanović K Soldo-Butković S Kralj M Soldo I Marjanović M Hanzer N Gmajnić R Glasnović M Timarac J 《Collegium antropologicum》2003,27(2):547-554
The aim of this retrospective study was to provide a survey of the incidence of stroke in Baranya, Croatia, on patients examined at Beli Manastir Health Center Department of Emergency from November 1, 1997 (the time of Baranya reintegration into the legal system of the Republic of Croatia after the war) till December 31, 2001. A total of 513 patients with symptoms of cerebrovascular diseases, or one patient every third day on an average, were examined. Total incidence of stroke was 16.09 per 10,000 population. The majority of patients were in the 61-80 age group with an incidence of 46.94/10,000 after the age of 60, 15-fold that was recorded in younger age groups. The most common risk factors recorded in examined group included hypertension, heart diseases, hyperlipidemia and diabetes mellitus. Total stroke mortality was 38.38%, whereas mortality in patients with hemorrhagic and ischemic stroke was 62.85% and 33.52%, respectively. The ratio of ischemic and hemorrhagic stroke in study subjects was 5:1, and in the causes of death 2.5:1. Out of 81 deceased stroke patients, 96.3% died within first 28 of admission. All of the patients with hemorrhagic stroke died within first 28 days, most within first 7 days (81.8%), whereas 94.9% of patients with ischemic stroke died within first 28 days. 相似文献
99.
A thermodynamic model is proposed describing swelling changes and swelling transitions of hybrid gels in which domains of folded chains are chemically built in as cross-links. These folded domains can be unfolded to random coils by osmotic forces produced by the synthetic gel matrix. Uncoiling takes place if the osmotic force acting on the cross-links exceeds the critical value. By unfolding, a new interacting surface is exposed to interactions and affects the swelling pressure. The chains of the folded domains may have ionized groups. The model is based on mean-field statistical-thermodynamic treatment of swelling of polyelectrolyte gels with finite extensibility of network chains. This study is related to hybrid hydrogels with built in protein motifs. A continuous change in external variables increasing the degree of swelling of the hydrogel brings about an abrupt increase in volume (transition) of the gel. The position and magnitude of the transition depend on structural parameters of the hybrid gel, such as fraction of the folded domains in the gel, degree of ionization of chains in the domain, presence of additional chemical cross-links, or degree of dilution at gel formation. Two options for reversibility of the changes are considered: (a) unfolding is irreversible and deswelling proceeds along other curve than swelling and (b) swelling is reversible when the osmotic force decrease below the critical value. In the latter case, swelling changes are described by a closed loop with two transitions. Under certain conditions (high dilution at network formation and sufficiently high degree of ionization of chains of the folded domains), a transition appears known as the collapse transition induced by balance of hydrophobic and hydrophillic interactions. This collapse transition induces the folding transition by which the folded domains are reformed. 相似文献
100.
Tachezy J Tachezy R Hampl V Sedinová M Vanacová S Vrlík M Van Ranst M Flegr J Kuldaa J 《The Journal of eukaryotic microbiology》2002,49(2):154-163
A number of reports suggest that the sexually transmitted pathogen of cattle, Tritrichomonasfoetus, and a gastrointestinal commensal of pigs, Tritrichomonas suis, are very similar and may be co-specific. A conclusive review of the taxonomic and nomenclatural status of these species has not been presented so far. Toward this end, we reexamined and compared porcine and bovine trichomonads with regard to their morphology, pathogenic potential, and DNA polymorphism. Using light and electron microscopy, no distinguishing features between T. foetus and T. suis strains were found in size, general morphology, and karyomastigont structure. Both bovine and porcine trichomonads showed pathogenic potential in the subcutaneous mouse assays and did not separate into distinct groups according to strain virulence. Three DNA fingerprinting methods (i.e. RFLP, RAPD, and PCR-based analysis of variable-length DNA repeats) that produce species-specific DNA fragment patterns did not distinguish between the bovine and porcine strains. Sequencing of a variable 502-bp DNA fragment as well as comparison of 16S rRNA gene sequences did not reveal species-specific differences between the cattle and porcine strains. Therefore, we conclude that T. foetus and T. suis belong to the same species. To prevent confusion that may arise from T. foetus-T. suis synonymy, we propose to suppress the older name suis and maintain its accustomed junior synonym foetus as a nomen protectum for both cattle and porcine trichomonads. The case has been submitted to the International Commission on Zoological Nomenclature for ruling under its plenary power. 相似文献