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Antioxidative enzymes during germination of two lines of Serbian spruce [Picea omorika (Pan .) Purkyně]
Prodanovi? Olivera,Prodanovi? R.,Bogdanovi? Jelena,Mitrovi? Aleksandra
Archives of Biological Sciences , 2007, DOI: 10.2298/abs0703209p
Abstract: Two lines of Picea omorika (Pan .) Purkyně were compared with respect to germination percentage as well as specific activity and isoenzyme pattern of catalase, superoxide dismutase, and peroxidase (POD) during germination. Line A had a higher germination percentage and higher enzyme activities in dry seeds and seedlings compared to line C. Peroxidase activity was not detected in dry seeds, but measured up to 10 U/g and 28 U/g on the 7th day of germination in lines C and A, respectively. The most abundant POD basic isoform in seedlings of both lines (pI 8.2) was not found previously in needles of adult Serbian spruce trees of the same lines. .
Characterizing Model-Theoretic Dividing Lines via Collapse of Generalized Indiscernibles  [PDF]
Vincent Guingona,Cameron Donnay Hill,Lynn Scow
Mathematics , 2015,
Abstract: We use the notion of collapse of generalized indiscernible sequences to classify various model theoretic dividing lines. In particular, we use collapse of n-multi-order indiscernibles to characterize op-dimension n; collapse of function-space indiscernibles (i.e. parameterized equivalence relations) to characterize rosy theories; and finally, convex equivalence relation indiscernibles to characterize NTP2 theories.
Hyperspectral pan-sharpening: a variational convex constrained formulation to impose parallel level lines, solved with ADMM  [PDF]
Alexis Huck,Fran?ois de Vieilleville,Pierre Weiss,Manuel Grizonnet
Computer Science , 2014,
Abstract: In this paper, we address the issue of hyperspectral pan-sharpening, which consists in fusing a (low spatial resolution) hyperspectral image HX and a (high spatial resolution) panchromatic image P to obtain a high spatial resolution hyperspectral image. The problem is addressed under a variational convex constrained formulation. The objective favors high resolution spectral bands with level lines parallel to those of the panchromatic image. This term is balanced with a total variation term as regularizer. Fit-to-P data and fit-to-HX data constraints are effectively considered as mathematical constraints, which depend on the statistics of the data noise measurements. The developed Alternating Direction Method of Multipliers (ADMM) optimization scheme enables us to solve this problem efficiently despite the non differentiabilities and the huge number of unknowns.
Sensitivity of Monocytic Cell Lines to Verapamil in vitro
Fatemeh Hajighasemi,Neda Kakadezfuli
Research Journal of Biological Sciences , 2012, DOI: 10.3923/rjbsci.2012.209.214
Abstract: Verapamil as a calcium channel blocker broadly used in therapy of many cardiovascular diseases such as hypertension and arrhythmia. Moreover, the anti-tumor effect of several chemotherapeutic agents has been increased by verapamil. Also, the inhibitory effect of some calcium channel blockers on tumor cell growth and invasion has been reported. Moreover, induction of apoptosis in leukemia cells by a Ca2+ channel blocker has been revealed. The present study was conducted to evaluate the verapamil cytotoxicity in two human monocytic cell lines in vitro. The human monocytic U937 and THP1 cells were cultured in complete RPMI medium. Then, the cells at logarhytmic growth phase were incubated with different concentrations of verapamil (0.01-2 mM) for 24, 48 and 72 h periods. Next, the cell viability was assessed with trypan blue dye exclusion and MTT 3-(4, 5-dimethyl thiazol-2, 5-diphenyltetrazoliumbromide) methods. Verapamil significantly decreased the proliferation of U937 and THP1 cells dose and time dependently. This cytotoxic effect after 24, 48 and 72 h incubation time was shown at ≥1, 0.2 and 0.1 mM concentration for U937 and at ≥1, 1 and 0.2 mM concentration for THP1 cells, respectively. In U937 cells verapamil cytotoxicity at 0.2 mM concentration, significantly increased with time in this order 72>48 h (p<0.05). According to the results of this study, verapamil showed a dose and time-dependent cytotoxic effect on human U937 and THP1 cells. Moreover, the sensitivity of U937 and THP1 cells to verapamil was somewhat different. So, the anti-tumor effects of verapamil reported by several investigations may be in part due to its direct cytotoxic effects. Thus, verapamil with potential inhibitory effect on leukemic U937 and THP1 cells growth might be useful as an anti-proliferative agent in leukemia.
Sensitivity of the limit shape of sample clouds from meta densities  [PDF]
Guus Balkema,Paul Embrechts,Natalia Nolde
Mathematics , 2009, DOI: 10.3150/11-BEJ370
Abstract: The paper focuses on a class of light-tailed multivariate probability distributions. These are obtained via a transformation of the margins from a heavy-tailed original distribution. This class was introduced in Balkema et al. (J. Multivariate Anal. 101 (2010) 1738-1754). As shown there, for the light-tailed meta distribution the sample clouds, properly scaled, converge onto a deterministic set. The shape of the limit set gives a good description of the relation between extreme observations in different directions. This paper investigates how sensitive the limit shape is to changes in the underlying heavy-tailed distribution. Copulas fit in well with multivariate extremes. By Galambos's theorem, existence of directional derivatives in the upper endpoint of the copula is necessary and sufficient for convergence of the multivariate extremes provided the marginal maxima converge. The copula of the max-stable limit distribution does not depend on the margins. So margins seem to play a subsidiary role in multivariate extremes. The theory and examples presented in this paper cast a different light on the significance of margins. For light-tailed meta distributions, the asymptotic behaviour is very sensitive to perturbations of the underlying heavy-tailed original distribution, it may change drastically even when the asymptotic behaviour of the heavy-tailed density is not affected.
Establishment of a drug sensitivity panel using human lung cancer cell lines.
Matsushita A,Tabata M,Ueoka H,Kiura K
Acta Medica Okayama , 1999,
Abstract: We established a drug sensitivity panel consisting of 24 human lung cancer cell lines. Using this panel, we evaluated 26 anti-cancer agents: three alkylators, three platinum compounds, four antimetabolites, one topoisomerase I inhibitor, five topoisomerase II inhibitors, seven antimitotic agents and three tyrosine kinase inhibitors. This panel showed the following: a) Drug sensitivity patterns reflected their clinically-established patterns of action. For example, doxorubicin and etoposide were shown to be active against small cell lung cancer cell lines and mitomycin-C and 5-fluorouracil were active against non-small cell lung cancer cell lines, in agreement with clinical data. b) Correlation analysis of the mean graphs derived from the logarithm of IC50 values of the drugs gave insight into the mechanism of each drug's action. Thus, two drug combinations with reverse or no correlation, such as the combination of cisplatin and vinorelbine, might be good candidates for the ideal two drug combination in the treatment of lung cancer, as is being confirmed in clinical trials. c) Using cluster analysis of the cell lines in the panel with their drug sensitivity patterns, we could classify the cell lines into four groups depending on the drug sensitivity similarity. This classification will be useful to elucidate the cellular mechanism of action and drug resistance. Thus, our drug sensitivity panel will be helpful to explore new drugs or to develop a new combination of anti-cancer agents for the treatment of lung cancer.
Pan Pan Theatre Aesthetics  [cached]
Noelia Ruiz
Revista Brasileira de Estudos da Presen?a , 2013,
Abstract: This paper aims to elucidate Pan Pan Theatre’s aesthetics through an instance of their rehearsal process, especially in terms of their performance mode, which cannot be dissociated from their manifest intention to create a specific atmosphere. This paper explores Michael Kirby’s continuum between non-matrixed performance and complex acting, with regard to Pan Pan Theatre’s performance style, which enhances a particular conception of time and space as metonymic.
Characterizing Acupuncture Stimuli Using Brain Imaging with fMRI - A Systematic Review and Meta-Analysis of the Literature  [PDF]
Wenjing Huang, Daniel Pach, Vitaly Napadow, Kyungmo Park, Xiangyu Long, Jane Neumann, Yumi Maeda, Till Nierhaus, Fanrong Liang, Claudia M. Witt
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0032960
Abstract: Background The mechanisms of action underlying acupuncture, including acupuncture point specificity, are not well understood. In the previous decade, an increasing number of studies have applied fMRI to investigate brain response to acupuncture stimulation. Our aim was to provide a systematic overview of acupuncture fMRI research considering the following aspects: 1) differences between verum and sham acupuncture, 2) differences due to various methods of acupuncture manipulation, 3) differences between patients and healthy volunteers, 4) differences between different acupuncture points. Methodology/Principal Findings We systematically searched English, Chinese, Korean and Japanese databases for literature published from the earliest available up until September 2009, without any language restrictions. We included all studies using fMRI to investigate the effect of acupuncture on the human brain (at least one group that received needle-based acupuncture). 779 papers were identified, 149 met the inclusion criteria for the descriptive analysis, and 34 were eligible for the meta-analyses. From a descriptive perspective, multiple studies reported that acupuncture modulates activity within specific brain areas, including somatosensory cortices, limbic system, basal ganglia, brain stem, and cerebellum. Meta-analyses for verum acupuncture stimuli confirmed brain activity within many of the regions mentioned above. Differences between verum and sham acupuncture were noted in brain response in middle cingulate, while some heterogeneity was noted for other regions depending on how such meta-analyses were performed, such as sensorimotor cortices, limbic regions, and cerebellum. Conclusions Brain response to acupuncture stimuli encompasses a broad network of regions consistent with not just somatosensory, but also affective and cognitive processing. While the results were heterogeneous, from a descriptive perspective most studies suggest that acupuncture can modulate the activity within specific brain areas, and the evidence based on meta-analyses confirmed some of these results. More high quality studies with more transparent methodology are needed to improve the consistency amongst different studies.
Inhibition of DNA methyltransferase activity and expression by treatment with the pan-deacetylase inhibitor panobinostat in hepatocellular carcinoma cell lines  [cached]
Zopf Steffen,Ocker Matthias,Neureiter Daniel,Alinger Beate
BMC Cancer , 2012, DOI: 10.1186/1471-2407-12-386
Abstract: Background Hepatocellular carcinoma (HCC) still represents an unmet medical need. Epigenetic inactivation of tumor suppressor genes like RASSF1A or APC by overexpression of DNA methyltransferases (DNMTs) has been shown to be common in HCC and to be linked to the overall prognosis of patients. Inhibitors of protein and histone deacetylases (DACi) have been demonstrated to possess strong anti-tumor effects in HCC models. Methods We therefore investigated whether DACi also has any influence on the expression and activity of DNMTs and methylated target genes in HepG2 and Hep3B cell culture systems and in a xenograft model by immunohistochemistry, westernblotting, RT-qPCR and methylation-specific PCR. Results Our findings demonstrate a rapid inhibition of DNMT activity 6 h after treatment with 0.1 μM of the pan-DACi panobinostat. A downregulation of DNMT mRNAs and protein were also observed at later points in time. This loss of DNMT activity and expression was paralleled by a diminished methylation of the target genes RASSF1A and APC and a concomitant re-expression of APC mRNA and protein. Analysis of HepG2 xenograft specimens confirmed these results in vivo. Conclusion We suggest a dual mode of action of DACi on DNA methylation status: a rapid inhibition of enzyme activity due to interference with posttranslational acetylation and a delayed effect on transcriptional control of DNMT genes by HDAC or miRNA mechanisms.
Screening the Drug Sensitivity Genes Related to GEM and CDDP in the Lung Cancer Cell-lines  [PDF]
Chunyu YANG,Zhennan TIAN,Wei LIU,Li CAI
Chinese Journal of Lung Cancer , 2009,
Abstract: Background and objective Screening of small-cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) cell lines with gemcitabine hydrochloride (GEM) and cisplatin (CDDP) related to drug sensitivity gene might clarify the action mechanism of anti-cancer drugs and provide a new clue for overcoming drug resistance and the development of new anti-cancer drugs, and also provide theoretical basis for the clinical treatment of individual. Methods The drug sensitivity of CDDP and GEM in 4 SCLC cell lines and 6 NSCLC cell lines was determined using MTT colorimetric assay, while the cDNA macroarray was applied to detect the gene expression state related to drug sensitivity of 10 lung cancer cell line in 1 291, and the correlation between the two was analysized. Results There were 6 genes showing significant positive correlation (r≥0.632, P < 0.05) with GEM sensitivity; 45 genes positively related to CDDP; another 41 genes related to both GEM and CDDP (r≥± 0.4). Lung cancer with GEM and CDDP sensitivity of two types of drugs significantly related genes were Metallothinein (Signal transduction molecules), Cathepsin B (Organization protease B) and TIMP1 (Growth factor); the GEM, CDDP sensitivity associated genes of lung cancer cell lines mainly distributed in Metallothinein, Cathepsin B, growth factor TIMP1 categories. Conclusion There existed drug-related sensitive genes of GEM, CDDP in SCLC and NSCLC cell lines; of these genes, Metallothinein, Cathepsin B and TIMP1 genes presented a significant positive correlation with GEM drug sensitivity, a significant negative correlation with CDDP drug sensitivity.
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