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Sample records for arto pulk eva-liisa

  1. Activation of autophagy in rat brain cells following focal cerebral ischemia reperfusion through enhanced expression of Atg1/pULK and LC3

    PubMed Central

    YU, JINGWEI; BAO, CUIFEN; DONG, YANRU; LIU, XIA

    2015-01-01

    The present study aimed to investigate the activation of Atg1/pULK, and LC3 in the cerebral cortex following focal cerebral ischemia reperfusion (CIR) injury, thereby examining its effect on autophagy in brain cells. Rat CIR models were established using the technique of middle cerebral artery occlusion. The neurological function score, TTC staining and the water content of brain tissue were used to evaluate the CIR model. Levels of autophagy in the brain cells were examined at different time-points following CIR damage using electron microscopy. Immunohistochemistry and western blot analysis were also used for the qualitative and quantitative detection of levels of Atg1/pULK and LC3 in the cerebral cortex. Autophagy was observed in the early stage of CIR, and the expression of Atg1/pULK and LC3 were observed 1 h following CIR in the rats and reached peak expression levels after12 h, which following which the they gradually decreased. These results suggested Atg1/pULK and LC3 are key in the regulation of autophagy following CIR in the rat brain. PMID:26018745

  2. Characterization of three bioenergetically active respiratory terminal oxidases in the cyanobacterium Synechocystis sp. strain PCC 6803.

    PubMed

    Pils, D; Schmetterer, G

    2001-09-25

    Synechocystis sp. PCC 6803 contains three respiratory terminal oxidases (RTOs): cytochrome c oxidase (Cox), quinol oxidase (Cyd), and alternate RTO (ARTO). Mutants lacking combinations of the RTOs were used to characterize these key enzymes of respiration. Pentachlorophenol and 2-heptyl-4-hydroxy-quinoline-N-oxide inhibited Cyd completely, but had little effect on electron transport to the other RTOs. KCN inhibited all three RTOs but the in vivo K(I) for Cox and Cyd was quite different (7 vs. 27 microM), as was their affinity for oxygen (K(M) 1.0 vs. 0.35 microM). ARTO has a very low respiratory activity. However, when uptake of 3-O-methylglucose, an active H+ co-transport, was used to monitor energization of the cytoplasmic membrane, ARTO was similarly effective as the other RTOs. As removal of the gene for cytochrome c(553) had the same effects as removal of ARTO genes, we propose that the ARTO might be a second Cox. The possible functions, localization and regulation of the RTOs are discussed.

  3. Asymptotic and chaotic solutions of a singularly perturbed Nagumo-type equation

    NASA Astrophysics Data System (ADS)

    Boscaggin, Alberto; Dambrosio, Walter; Papini, Duccio

    2015-10-01

    We deal with the singularly perturbed Nagumo-type equation where ɛ >0 is a real parameter and a:{R}\\to {R} is a piecewise constant function satisfying 0  <  a(s)  <  1 for all s. For small ɛ, we prove the existence of chaotic, homoclinic and heteroclinic solutions. We use a dynamical systems approach, based on the Stretching Along Paths technique and on the Conley-Wa{\\dot{z}} ewski’s method. Supported by the project Equazioni differenziali ordinarie sulla retta reale of GNAMPA-I.N.d.A.M., Italy. The second author is supported by the P.R.I.N. Project ‘Variational and perturbative aspects of nonlinear differential problems’

  4. Tetrandrine induces cell death in SAS human oral cancer cells through caspase activation-dependent apoptosis and LC3-I and LC3-II activation-dependent autophagy.

    PubMed

    Huang, An-Cheng; Lien, Jin-Cherng; Lin, Meng-Wei; Yang, Jai-Sing; Wu, Ping-Ping; Chang, Shu-Jen; Lai, Tung-Yuan

    2013-08-01

    Numerous studies have demonstrated that autophagy is associated with cancer development. Thus, agents to induce autophagy could be employed in some cases for the treatment of cancer. Our results showed that tetrandrine significantly decreased the viability of SAS cells in a concentration- and time-dependent manner. Tetrandrine induced nuclear condensation, demonstrated by DAPI staining. The early events in apoptosis analysed by Annexin V/PI staining indicated that the percentage of cells staining positive for Annexin V was slightly increased in SAS cells with tetrandrine treatment but was much lower following bafilomycin A1 pre-treatment. Tetrandrine caused AVO and MDC induction in SAS cells in a concentration-dependent manner by fluorescence microscopy. Tetrandrine also caused LC-3 expression in SAS cells in a time-dependent manner. Our results show that tetrandrine treatment induced the levels of cleaved caspase-3 in a concentration- and time-dependent manner. Tetrandrine treatment induced the levels of LC-3 II, Atg-5, beclin-1, p-S6, p-ULK, p-mTOR, p-Akt (S473) and raptor. Tetrandrine decreased cell viability, but bafilomycin A1, 3-MA, chloroquine and NAC protected tetrandrine-treated SAS cells against decrease of cell viability. Atg-5, beclin-1 siRNA decreased tetrandrine-induced cleaved caspase-3 and cleaved PARP in SAS cells and protected tetrandrine-treated SAS cells against decrease in cell viability. Chloroquine, NAC and bafilomycin A1 also decreased tetrandrine-induced cleaved caspase-3 and cleaved PARP in SAS cells. Our results indicate the tetrandrine induces apoptosis and autophagy of SAS human cancer cells via caspase-dependent and LC3-I and LC3-II‑dependent pathways.

  5. Analysis of eight out genes in a cluster required for pectic enzyme secretion by Erwinia chrysanthemi: sequence comparison with secretion genes from other gram-negative bacteria.

    PubMed Central

    Lindeberg, M; Collmer, A

    1992-01-01

    Many extracellular proteins produced by Erwinia chrysanthemi require the out gene products for transport across the outer membrane. In a previous report (S. Y. He, M. Lindeberg, A. K. Chatterjee, and A. Collmer, Proc. Natl. Acad. Sci. USA 88:1079-1083, 1991) cosmid pCPP2006, sufficient for secretion of Erwinia chrysanthemi extracellular proteins by Escherichia coli, was partially sequenced, revealing four out genes sharing high homology with pulH through pulK from Klebsiella oxytoca. The nucleotide sequence of eight additional out genes reveals homology with pulC through pulG, pulL, pulM, pulO, and other genes involved in secretion by various gram-negative bacteria. Although signal sequences and hydrophobic regions are generally conserved between Pul and Out proteins, four out genes contain unique inserts, a pulN homolog is not present, and outO appears to be transcribed separately from outC through outM. The sequenced region was subcloned, and an additional 7.6-kb region upstream was identified as being required for secretion in E. coli. out gene homologs were found on Erwinia carotovora cosmid clone pAKC651 but were not detected in E. coli. The outC-through-outM operon is weakly induced by polygalacturonic acid and strongly expressed in the early stationary phase. The out and pul genes are highly similar in sequence, hydropathic properties, and overall arrangement but differ in both transcriptional organization and the nature of their induction. Images PMID:1429461

  6. V834 CAR = Nova Car 2012 = TCP J10502000-6406480

    NASA Astrophysics Data System (ADS)

    Waagen, Elizabeth O.

    2012-03-01

    V834 CAR = Nova Car 2012 = TCP J10502000-6406480 was discovered by John Seach, Chatsworth Island, NSW, Australia, at magnitude 10.2 on 3 images with digital SLR, 50 mm f/1.0 lens on 2012 February 26.543 UT. The discovery was confirmed by Arto Oksanen, Muurame, Finland, and Caisey Harlingten at V=10.4 from CCD images taken 2012 March 1.1552 UT with a 0.50-m telescope in San Pedro de Atacama, Chile. Coordinates (from Oksanen and Harlingten): RA 10 50 19.66 Dec. -64 06 46.7 (J2000.0). Red spectra by F. M. Walter, Stony Brook University, and M. Hernandez, Cerro Tololo Interamerican Observatory, taken Mar. 7.01 UT with the SMARTS 1.5-m telescope (+ RC spectrograph) indicate the object appears to be a classical Fe II nova near maximum. N. N. Samus, on behalf of the GCVS team, reports that the name V834 Car has been assigned to this nova. The object was listed on Central Bueau for Astronomical Telegrams Transient Objects Confirmation Page (TOCP) as TCP J10502000-6406480. The discovery was initially announced in AAVSO Special Notice #266 (Waagen); additional information was published in IAU CBET 3040 (Daniel W. E. Green, ed.) and IAU Circular 9251 (Green, ed.). Finder charts and over 3,200 visual and photometric observations of V834 Car are available from the AAVSO (http://www.aavso.org). AAVSO International Database observations show that from its discovery at magnitude 10.4 on 2012 Mar. 1-2 UT, the nova has declined to magnitude 12.2 as of 2012 Mar. 15-16 UT.

  7. Construction of an Indonesian herbal constituents database and its use in Random Forest modelling in a search for inhibitors of aldose reductase.

    PubMed

    Naeem, Sadaf; Hylands, Peter; Barlow, David

    2012-02-01

    Data on phytochemical constituents of plants commonly used in traditional Indonesian medicine have been compiled as a computer database. This database (the Indonesian Herbal constituents database, IHD) currently contains details on ∼1,000 compounds found in 33 different plants. For each entry, the IHD gives details of chemical structure, trivial and systematic name, CAS registry number, pharmacology (where known), toxicology (LD(50)), botanical species, the part(s) of the plant(s) where the compounds are found, typical dosage(s) and reference(s). A second database has been also been compiled for plant-derived compounds with known activity against the enzyme, aldose reductase (AR). This database (the aldose reductase inhibitors database, ARID) contains the same details as the IHD, and currently comprises information on 120 different AR inhibitors. Virtual screening of all compounds in the IHD has been performed using Random Forest (RF) modelling, in a search for novel leads active against AR-to provide for new forms of symptomatic relief in diabetic patients. For the RF modelling, a set of simple 2D chemical descriptors were employed to classify all compounds in the combined ARID and IHD databases as either active or inactive as AR inhibitors. The resulting RF models (which gave misclassification rates of 21%) were used to identify putative new AR inhibitors in the IHD, with such compounds being identified as those giving RF scores >0.5 (in each of the three different RF models developed). In vitro assays were subsequently performed for four of the compounds obtained as hits in this in silico screening, to determine their inhibitory activity against human recombinant AR. The two compounds having the highest RF scores (prunetin and ononin) were shown to have the highest activities experimentally (giving ∼58% and ∼52% inhibition at a concentration of 15μM, respectively), while the compounds with lowest RF scores (vanillic acid and cinnamic acid) showed the