P-glycoprotein-mediated resistance to chemotherapy in cancer cells: using recombinant cytosolic domains to establish structure-function relationships

Resistance to chemotherapy in cancer cells is mainly mediated by overexpression of P-glycoprotein (Pgp), a plasma membrane ATP-binding cassette (ABC) transporter which extrudes cytotoxic drugs at the expense of ATP hydrolysis. Pgp consists of two homologous halves each containing a transmembrane domain and a cytosolic nucleotide-binding domain (NBD) which contains two consensus Walker motifs, A and B, involved in ATP binding and hydrolysis. The protein also contains an S signature characteristic of ABC transporters. The molecular mechanism of Pgp-mediated drug transport is not known. Since the transporter has an extraordinarily broad substrate specificity, its cellular function has been described as a "hydrophobic vacuum cleaner". The limited knowledge about the mechanism of Pgp, partly due to the lack of a high-resolution structure, is well reflected in the failure to efficiently inhibit its activity in cancer cells and thus to reverse multidrug resistance (MDR). In contrast to the difficulties encountered when studying the full-length Pgp, the recombinant NBDs can be obtained in large amounts as soluble proteins. The biochemical and biophysical characterization of recombinant NBDs is shown here to provide a suitable alternative route to establish structure-function relationships. NBDs were shown to bind ATP and analogues as well as potent modulators of MDR, such as hydrophobic steroids, at a region close to the ATP site. Interestingly, flavonoids also bind to NBDs with high affinity. Their binding site partly overlaps both the ATP-binding site and the steroid-interacting region. Therefore flavonoids constitute a new promising class of bifunctional modulators of Pgp.

Forecasting financial weather - can we foresee market sentiment? Quantitative analysis of nodal prices in the New Zealand Electricity Spot Market

Time series of hourly electricity spot prices have peculiar properties. Electricity is by its nature difficult to store and has to be available on demand. There are many reasons for wanting to understand correlations in price movements, e.g. risk management purposes. The entire analysis carried out in this thesis has been applied to the New Zealand nodal electricity prices: offer prices (from 29 May 2002 to 31 March 2009) and final prices (from 1 January 1999 to 31 March 2009). In this paper, such natural factors as location of the node and generation type in the node that effects the correlation between nodal prices have been reviewed. It was noticed that the geographical factor affects the correlation between nodes more than others. Therefore, the visualisation of correlated nodes was done. However, for the offer prices the clear separation of correlated and not correlated nodes was not obtained. Finally, it was concluded that location factor most strongly affects correlation of electricity nodal prices; problems in visualisation probably associated with power losses when the power is transmitted over long distance.

Control of the rat angiotensin I converting enzyme gene by CRE-like sequences

We characterized the role of potential cAMP-responsive elements (CRE) in basal and in induced angiotensin converting enzyme (ACE) gene promoter activity in order to shed light on the regulation of somatic ACE expression. We identified stimulators and repressors of basal expression between 122 and 288 bp and between 415 and 1303 bp upstream from the transcription start site, respectively, using a rabbit endothelial cell (REC) line. These regions also contained elements associated with the response to 8BrcAMP. When screening for CRE motifs we found pCRE, a proximal sequence between 209 and 222 bp. dCRE, a distal tandem of two CRE-like sequences conserved between rats, mice and humans, was detected between 834 and 846 bp. Gel retardation analysis of nuclear extracts of REC indicated that pCRE and dCRE bind to the same protein complexes as bound by a canonical CRE. Mutation of pCRE and dCRE in REC established the former as a positive element and the latter as a negative element. In 293 cells, a renal cell line, pCRE and dCRE are negative regulators. Co-transfection of ATF-2 or ATF-2 plus c-Jun repressed ACE promoter activity, suggesting that the ACE gene is controlled by cellular stress. Although mapping of cAMP responsiveness was consistent with roles for pCRE and dCRE, mutation analysis indicated that they were not required for cAMP responsiveness. We conclude that the basal activity of the somatic ACE promoter is controlled by proximal and distal CREs that can act as enhancers or repressors depending on the cell context.

Aurapten, a coumarin with growth inhibition against Leishmania major promastigotes

Several natural compounds have been identified for the treatment of leishmaniasis. Among them are some alkaloids, chalcones, lactones, tetralones, and saponins. The new compound reported here, 7-geranyloxycoumarin, called aurapten, belongs to the chemical class of the coumarins and has a molecular weight of 298.37. The compund was extracted from the Rutaceae species Esenbeckia febrifuga and was purified from a hexane extract starting from 407.7 g of dried leaves and followed by four silica gel chromatographic fractionation steps using different solvents as the mobile phase. The resulting compound (47 mg) of shows significant growth inhibition with an LD50 of 30 µM against the tropical parasite Leishmania major, which causes severe clinical manifestations in humans and is endemic in the tropical and subtropical regions. In the present study, we investigated the atomic structure of aurapten in order to determine the existence of common structural motifs that might be related to other coumarins and potentially to other identified inhibitors of Leishmania growth and viability. This compound has a comparable inhibitory activity of other isolated molecules. The aurapten is a planar molecule constituted of an aromatic system with electron delocalization. A hydrophobic side chain consisting of ten carbon atoms with two double bonds and negative density has been identified and may be relevant for further compound synthesis.

Intrinsic bent DNA sites in the chromosomal replication origin of Xylella fastidiosa 9a5c

The features of the nucleotide sequences in both replication and promoter regions have been investigated in many organisms. Intrinsically bent DNA sites associated with transcription have been described in several prokaryotic organisms. The aim of the present study was to investigate intrinsic bent DNA sites in the segment that holds the chromosomal replication origin, oriC, of Xylella fastidiosa 9a5c. Electrophoretic behavior analyses, as well as in silico analyses of both the 2-D projection and helical parameters, were performed. The chromosomal segment analyzed contains the initial sequence of the rpmH gene, an intergenic region, the dnaA gene, the oriC sequence, and the 5' partial sequence of the dnaN gene. The analysis revealed fragments with reduced electrophoretic mobility, which indicates the presence of curved DNA segments. The analysis of the helical parameter ENDS ratio revealed three bent DNA sites (b1, b2, and b3) located in the rpmH-dnaA intergenic region, the dnaA gene, and the oriC 5' end, respectively. The chromosomal segment of X. fastidiosa analyzed here is rich in phased AT tracts and in CAnT motifs. The 2-D projection indicated a segment whose structure was determined by the cumulative effect of all bent DNA sites. Further, the in silico analysis of the three different bacterial oriC sequences indicated similar negative roll and twist >34.00° values. The DnaA box sequences, and other motifs in them, may be associated with the intrinsic DNA curvature.

Transduction motif analysis of gastric cancer based on a human signaling network

To investigate signal regulation models of gastric cancer, databases and literature were used to construct the signaling network in humans. Topological characteristics of the network were analyzed by CytoScape. After marking gastric cancer-related genes extracted from the CancerResource, GeneRIF, and COSMIC databases, the FANMOD software was used for the mining of gastric cancer-related motifs in a network with three vertices. The significant motif difference method was adopted to identify significantly different motifs in the normal and cancer states. Finally, we conducted a series of analyses of the significantly different motifs, including gene ontology, function annotation of genes, and model classification. A human signaling network was constructed, with 1643 nodes and 5089 regulating interactions. The network was configured to have the characteristics of other biological networks. There were 57,942 motifs marked with gastric cancer-related genes out of a total of 69,492 motifs, and 264 motifs were selected as significantly different motifs by calculating the significant motif difference (SMD) scores. Genes in significantly different motifs were mainly enriched in functions associated with cancer genesis, such as regulation of cell death, amino acid phosphorylation of proteins, and intracellular signaling cascades. The top five significantly different motifs were mainly cascade and positive feedback types. Almost all genes in the five motifs were cancer related, including EPOR,MAPK14, BCL2L1, KRT18,PTPN6, CASP3, TGFBR2,AR, and CASP7. The development of cancer might be curbed by inhibiting signal transductions upstream and downstream of the selected motifs.

Effects of 5-aza-2′deoxycytidine on RECK gene expression and tumor invasion in salivary adenoid cystic carcinoma

Reversion-inducing cysteine-rich protein with kazal motifs (RECK), a novel tumor suppressor gene that negatively regulates matrix metalloproteinases (MMPs), is expressed in various normal human tissues but downregulated in several types of human tumors. The molecular mechanism for this downregulation and its biological significance in salivary adenoid cystic carcinoma (SACC) are unclear. In the present study, we investigated the effects of a DNA methyltransferase (DNMT) inhibitor, 5-aza-2′deoxycytidine (5-aza-dC), on the methylation status of the RECK gene and tumor invasion in SACC cell lines. Methylation-specific PCR (MSP), Western blot analysis, and quantitative real-time PCR were used to investigate the methylation status of the RECK gene and expression of RECK mRNA and protein in SACC cell lines. The invasive ability of SACC cells was examined by the Transwell migration assay. Promoter methylation was only found in the ACC-M cell line. Treatment of ACC-M cells with 5-aza-dC partially reversed the hypermethylation status of the RECK gene and significantly enhanced the expression of mRNA and protein, and 5-aza-dC significantly suppressed ACC-M cell invasive ability. Our findings showed that 5-aza-dC inhibited cancer cell invasion through the reversal of RECKgene hypermethylation, which might be a promising chemotherapy approach in SACC treatment.

Myocardial ischemic preconditioning upregulated protein 1(Mipu1):zinc finger protein 667 - a multifunctional KRAB/C2H2 zinc finger protein

Myocardial ischemic preconditioning upregulated protein 1 (Mipu1) is a newly discovered upregulated gene produced in rats during the myocardial ischemic preconditioning process. Mipu1 cDNA contains a 1824-base pair open reading frame and encodes a 608 amino acid protein with an N-terminal Krüppel-associated box (KRAB) domain and classical zinc finger C2H2 motifs in the C-terminus. Mipu1 protein is located in the cell nucleus. Recent studies found that Mipu1 has a protective effect on the ischemia-reperfusion injury of heart, brain, and other organs. As a nuclear factor, Mipu1 may perform its protective function through directly transcribing and repressing the expression of proapoptotic genes to repress cell apoptosis. In addition, Mipu1 also plays an important role in regulating the gene expression of downstream inflammatory mediators by inhibiting the activation of activator protein-1 and serum response element.

Marks of Fire, Value and Faith. Swords with Ferrous Inlays in Finland during the Late Iron Age (ca. 700–1200 AD)

This study explores swords with ferrous inlays found in Finland and dating from the late Iron Age, ca. 700–1200 AD. These swords reflect profound changes not only in styles and fashion but also in the technology of hilts and blades. This study explores how many of these kinds of swords are known from Finland, how they were made and where, what their status was in Late Iron Age Finland, and where the Finnish finds stand in accordance with other areas of Europe. The various methods included measuring of the finds and statistics. The main method of revealing the inlaid marks was radiography due to its non-destructive nature. In cases where inlays were visible without radiography, their details were inspected via microscopy. To study the materials and manufacture of inlaid swords, a sample of them was metallographically analysed to determine the forging technologies and nature of used materials. Furthermore, the manufacture was also studied with experimental approaches. As a result, a catalogue of 151 swords with ferrous inlays was created. This number is relatively high compared with other European countries, although systematic studies have been conducted in only some countries. The inlaid motifs were classified into five distinct categories to help the classification. To summarize, almost every documented inlaid sword was unique in some respect including measurements, inlaid motifs and materials of blades and inlays. Technological variation was also present, some blades being poorer and some of higher quality in spite of the inlaid motifs. Misspelt inscriptions as well as letter-like marks were common in Finland and also in Scandinavia. Furthermore, the provenance of iron and steel used in some blades hints at Scandinavian ores. The above observations, along with the experimental results indicating the existence of multiple alternative techniques of inlaying, suggest that these swords were manufactured locally in Scandinavia, most likely in imitation of Continental European models. Inlaid swords were valued partly for their assumed functionality in combat, as evidenced by damage on some examined blades, or they were valued for their inlays, which could have had fashionable or symbolical meanings bound to local beliefs.

Horae ad usum romanum

F. 1-12v. Calendrier en français, à l’encre rouge et noire, où l’on remarque des formes dialectales picardes et plusieurs saints du Nord : « sainte Audegonde » (30 janvier) ; « le Candelier » (2 févr.) ; « ste Gertrude » (17 mars) ; « saint Quentin » (2 mai) ; « saint Ernoulx » [ep. Suessonensis] (16 août) ; « saint Bertin » (5 septembre) ; « saint Lambert » (17 septembre) ; « saint Franchois » (4 oct.) ; « saint Gillain » [mart. in Hannonia] (16 oct., Ghislain); « le jour st Estievene » (26 déc., rouge). Une deuxième main très cursive ajouté d’autres saints, dont « s. Amand » (6 févr.) ; « s. Waleri » (1er avril) ; « s. Fuscien » [mart. Ambianensis] (27 juin et 10 déc.) ; « s. Firmin » [mart. Ambianensis] (25 septembre) ; « s. Bavon » (1er oct.). F. 13v-17v. « ... hore sancte Crucis». F. 18v-22v. « ... hore de sancto Spiritu ».F. 23v-85. « ... hore beate marie virginis secundum usum romanum ». F. 86v-94v. Office de la Vierge, selon les temps de l’année. « ... officum beate Marie virginis quod dicitur per totum adventum ad vesperas ».F.95-115. « ... septem psalmi penitentiales cum suis litaniis et precibus ». A noter « ... sancte Lamberte... sancte Rumolde [ep. Mechlinensis]... sancte Fursee [ab. Latiniacensis] ... sancte Amande... sancte Vedaste, sancte Bavo... sancte Philiberte... santa Ursula... sancta Brigida... sancta Aldegondis, sancta Gertrudis... ».F.116v-152v. « ... vigilie mortuorum » office des morts à l’usage de Sarum-Normandie-Metz ; cf. K. Ottosen, Responsories..., p. 242 (116v-151). — « Octo versus beati Bernardi ». « Illumina oculos meos ne umquam obdormiam... » ; cf. Leroquais, Livres d’heures, I, XXX-XXXI (151-152v).F.153-158v. « Initium sancti evvangelii secundum Johannem... secundum Lucam... secundum Matheum... secundum Marcum ».F. 158v-166. Suffrages aux saints : « Memoria de santo Johanne Baptista... ; devota oratio... » ; — « ... de sancto Adriano » ; — « ... de sancto Sebastiano » ; — « ... de sancto Anthonio » ; — « ... de sancto Quintino » ; — « ... de sancto Nicholae » ; — « ... de sancto Andrea » ; — « ... de sancto Fiacro ».F.166v-174v. Prières à la Vierge. « ... devotissima oratio ad beatem virginem Mariam ». « O intemerata... O Johannes... » (éd. Wilmart, Auteurs spirituels, 488-490) (166v-169v). — « Alia oratio ad beatam virginem Mariam ». « Obsecro te.... » (éd. Leroquais, Livres d’heures, II, 346-347) (169v-174). Les deux prières sont rédigées à la forme masculine. — « Laus Marie virginis ». « Salve regina... » (Analecta Hymnica, L, 318-319, n° 245) (174-174v). F. 175-184v. Suffrages aux saintes : « ... de santa Barbara » ; — « ... de sancta Margareta » ; — « ... de sancta Katerina » ; — « ... de sancta Maria Magdelena » ; — « ... de sancta Appolonia » ; — « ... de sancta Venicie [Venice, forme dérivée de Véronique] » « Veni sponsa Christi... Versus. Diffusa est gratia... Oratio. Exaudi nos Deus ut sicut de beate Venicie festivitate gaudemus, ita pie devotionis erudiamur. Per.... » ; sur le culte de sainte Véronique/Venice, en particulier à Paris, voir Gr. A. RUNNALS, Le mystère de sainte Venice, Exeter, 1980 (Textes littéraires) (175-180v). — Prières diverses : « ... quinque gaudia de beata virgine Maria » « Gaude Virgo mater Christi... » (éd. Leroquais, Livres d’heures, I, XXVI-XXVII) (180v-182). — « Oratio devota ad Jesum Christum ». « Ave domine Jhesu Christe verbum patris » (éd. Wilmart, Auteurs spirituels, 412 [III]) (182-183). — « Oratio devota que dicitur ad elevationem Domini ». « Ave verum corpus Domini nostri... » (éd. Szövérffy, Die Annalen , II, 298-299) (183-184). — « Memore de saint Miquiel », en latin (184-184v).

Postille super Psalterium. Latin 14254

Au f. 373, notes en français (XVe siècle)

Bible

F. B, liste de rentes léguées à l'église "de Chanayo". F. 321-324, anciennes gardes issues d'un manuscrit de droit (anciens feuillets 102, 101, 103 et 108).

Bible

Abbaye de Saint-Victor de Paris

[Recueil]

S. Augustinus, De baptismo parvulorum (1-30). - S. Anselmus Cantuariensis, Epistola ad monasterium Sancti Albani super Trinitatem (30-30v). - S. Gregorius, Epistolae (30v-31). - Remigius Autissiodorensis, Tractatus in Cantica canticorum (32-58). - Alcuinus, Expositio super Ecclesiastem (58-79v). - S. Augustinus, Altercatio contra Felicianum Arriomantem de unitate Trinitatis (79v-87). - Pseudo-Augustinus, De quattuor virtutibus caritatis (87-87v). - Alcuinus, De virtutibus et vitiis (88-94).- Liber Scintillarum (94-116v). - Isidorus Hispalensis, Sententiae de exemplis sanctorum (116v-121v). - De sacramentis ecclesiae (121v-124). - Teobaldus Stapensis, Epistola ad abbatem Saloberiensem (124-124v). - S. Bernardus Claraevallensis, Parabola de conflictu civitatis Babilonie et Jerusalem (124v-132v). - S. Augustinus, De incarnatione Domini contra Judeos (132v-133), Liber de predestinatione (133-136). - Hugo de Sancto Victore, Quaestio ("De eo quod dicitur: funes ceciderunt mihi in praeclaris") (136-136v). - S. Gregorius, Regula pastoralis (136v-137v). - S. Anselmus Cantuariensis, Cur Deus homo (138-155). - Robertus Pullus, Sermo (155-156). - Elucidarium (156-173v). - Adso Dermensis, D761De Antichristo ejusque signis (173v-174). - S. Augustinus, De libero arbitrio (174v). - Anselmus Lauduniensis, Sententiae de matrimonio (174v-177). - Sententiae variae (177-181).