991 resultados para 338.09


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Escherichia coli is suspected to be involved with Crohn's disease. Adherence and invasion to epithelial cells are properties commonly observed in these bacteria. Here, we present a draft genome sequence of E. coli D92/09, a multidrug-resistant strain, which besides showing these properties produces Shiga cytotoxin-1 and possibly other toxins.

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Maternal recognition of pregnancy is a process by which the conceptus signals its presence to the mother in order to prolong the life of the corpus luteum (CL) thus maintaining the pregnancy. This process occurs between days 15 and 19 after fertilization and is the most important biological challenge for obtaining satisfactory reproductive indices in bovine. Interferon-tau (IFN-τ) glycoprotein -secreted in the uterus by the conceptus- has a paracrine action inhibiting the expression of estrogen receptors (ESR1) and oxytocin (OXTR) in the endometrium, thus preventing the release of luteolytic pulses of prostaglandin F2 alpha (PGF2α), hormone responsible for the onset of luteolysis. IFN-τ also increases the expression of several interferon-stimulated genes (ISGs) in the uterus, CL, and blood cells. Direct endocrine action of IFN-τ on extrauterine tissues stimulates ISGs expression, which in the corpus luteum seems to be involved with luteal resistance to luteolytic action of PGF2α. This review discusses recent findings on the luteolysis mechanism in the bovine and endocrine and paracrine mechanisms such as IFN-τ during the maternal recognition of pregnancy.

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Mitochondria must grow with the growing cell to ensure proper cellular physiology and inheritance upon division. We measured the physical size of mitochondrial networks in budding yeast and found that mitochondrial network size increased with increasing cell size and that this scaling relation occurred primarily in the bud. The mitochondria-to-cell size ratio continually decreased in aging mothers over successive generations. However, regardless of the mother's age or mitochondrial content, all buds attained the same average ratio. Thus, yeast populations achieve a stable scaling relation between mitochondrial content and cell size despite asymmetry in inheritance.

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[EN]The age and growth of the sand sole Pegusa lascaris from the Canarian Archipelago were studied from 2107 fish collected between January 2005 and December 2007. To find an appropriate method for age determination, sagittal otoliths were observed by surface-reading and frontal section and the results were compared. The two methods did not differ significantly in estimated age but the surface-reading method is superior in terms of cost and time efficiency. The sand sole has a moderate life span, with ages up to 10 years recorded. Individuals grow quickly in their first two years, attaining approximately 48% of their maximum standard length; after the second year, their growth rate drops rapidly as energy is diverted to reproduction. Males and females show dimorphism in growth, with females reaching a slightly greater length and age than males. Von Bertalanffy, seasonalized von Bertalanfy, Gompertz, and Schnute growth models were fitted to length-at-age data. Akaike weights for the seasonalized von Bertalanffy growth model indicated that the probability of choosing the correct model from the group of models used was >0.999 for males and females. The seasonalized von Bertalanffy growth parameters estimated were: L? = 309 mm standard length, k = 0.166 yr?1, t0 = ?1.88 yr, C = 0.347, and ts = 0.578 for males; and L? = 318 mm standard length, k = 0.164 yr?1, t0 = ?1.653 yr, C = 0.820, and ts = 0.691 for females. Fish standard length and otolith radius are closely correlated (R2 = 0.902). The relation between standard length and otolith radius is described by a power function (a = 85.11, v = 0.906)

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„Untersuchung des Aggregationsverhaltens amphiphiler Diblockcopolymere in überkritischem Kohlendioxid mittels dynamischer Lichtstreuung“ In der vorliegenden Arbeit wurde die Mizellenbildung von Diblockcopolymeren des Typs PS-b-PDMS in überkritischem Kohlendioxid (CO2,SC) mittels dynamischer Lichtstreuung (DLS) charakterisiert. Zu diesem Zweck wurden Mischungen aus den Diblockcopolymeren in CO2,SC mit Styrol als Monomer druckabhängig auf diese Fähigkeit hin untersucht. Eine Mizellenbildung konnte anhand der gemessenen hydrodynamischen Radien Rh gezeigt werden. Um eine Vergleichsmöglichkeit gegenüber den mit Styrol gefüllten Kern-Hüllen-Mizellen zu bekommen, wurde das Diblockcopolymer PS-b-PDMS (9/27) zunächst ohne Styrol auf die Fähigkeit hin untersucht ungefüllte Mizellen zu bilden. Durch Druckvariation konnte ein kritischer Mizellendruck von ca. 46,7 MPa bei einer Temperatur von 338 K im Experiment bestätigt werden, der gefundene Rh liegt bei ca. 34 nm. Dagegen setzt die Aggregation bei einer PS-b-PDMS (9/27)/Styrol/CO2,SC- Mischung bei einem wesentlich niedrigeren Druck ein. Durch Druckvariation zwischen 38 MPa und 45,7 MPa wurde eine Größenänderung der Mizellen beobachtet. Durch zeitabhängige-DLS-Messungen am gleichen System bei einem bestimmten Druck wurde ein langsames Schrumpfen der Mizellen gefunden. Um den Einfluß der Blockgröße der verwendeten Amphiphile auf die Mizellenbildung zu untersuchen wurde das System PS-b-PDMS(6/37)/Styrol/CO2,SC mit Hilfe der DLS im Bereich zwischen 39,4 MPa und 43,1 MPa untersucht. Die Druckänderung zeigte für Rh ein nahezu invariantes Verhalten, daß durch eine verlängerte PDMS-Blocklänge und eine damit verbundene Kompensation der verschiedenen Wechselwirkungskräfte zwischen Mizellenkern, -hülle und CO2,SC erklärt werden kann. Im System PS-b-PDMS(6/16)/Styrol/CO2,SC konnte experimentell mit Hilfe der DLS erst nach einer ver-änderten molaren Zusammensetzung eine Mizellenbildung ab 40 MPa ermöglicht werden. Allerdings ändert sich auch in diesem System der hydrodynamische Radius ebenfalls mit dem Druck. Je nach Druck-, Temperatur- und molarer Zusammensetzung variiert die Tendenz der Systeme, Mizellen zu bilden die eine Emulsion stabilisieren können. Für die in Dispersions-Polymerisationsreaktionen eingesetzten Diblockcopolymere bedeutet dieses Ergebnis differenzierte Applikationsmöglichkeiten. Mit den ermittelten Konzentrationsverhältnissen an Amphiphil und Monomer konnte ein Bereich gefunden werden, in dem die thermodynamischen Bedingungen für die Mizellenbildung einerseits und die Vorraussetzungen für die DLS andererseits gegeben sind.

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La sindrome nefrosica (SN) è definita come la presenza concomitante di una proteinuria maggiore di 3.5g/24 h, ipoalbuminemia, ipercolesterolemia e presenza di edemi. I pazienti con SN sono più a rischio di quelli che presentano una nefropatia glomerulare non nefrosica (NNGD) per lo sviluppo di ipertensione, ipernatremia, complicazioni tromboemboliche e comparsa di insufficienza renale. In Medicina Veterinaria, la Letteratura riguardante l’argomento è molto limitata e non è ben nota la correlazione tra SN e gravità della proteinuria, ipoalbuminemia e sviluppo di tromboembolismo. L’obiettivo del presente studio retrospettivo è stato quello di descrivere e caratterizzare le alterazioni cliniche e clinicopatologiche che si verificano nei pazienti con rapporto proteine urinarie:creatinina urinaria (UPC) >2 con lo scopo di inquadrare con maggiore precisione lo stato clinico di questi pazienti e individuare le maggiori complicazioni a cui possono andare incontro. In un periodo di nove anni sono stati selezionati 338 cani e suddivisi in base ad un valore cut-off di UPC≥3.5. Valori mediani di creatinina, urea, fosforo, albumina urinaria, proteina C reattiva (CRP) e fibrinogeno sono risultati al di sopra del limite superiore dell’intervallo di riferimento, valori mediani di albumina sierica, ematocrito, antitrombina al disotto del limite inferiore di riferimento. Pazienti con UPC≥3.5 hanno mostrato concentrazioni di albumine, ematocrito, calcio, Total Iron Binding Capacity (TIBC), significativamente minori rispetto a quelli con UPC<3.5, concentrazioni di CRP, di urea e di fosforo significativamente maggiori. Nessuna differenza tra i gruppi nelle concentrazioni di creatinina colesterolo, trigliceridi, sodio, potassio, cloro, ferro totale e pressione sistolica. I pazienti con UPC≥3.5 si trovano verosimilmente in uno “stato infiammatorio” maggiore rispetto a quelli con UPC<3.5, questa ipotesi avvalorata dalle concentrazioni minori di albumina, di transferrina e da una concentrazione di CRP maggiore. I pazienti con UPC≥3.5 non presentano concentrazioni di creatinina più elevate ma sono maggiormente a rischio di anemia.

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In this study two ophiolites and a mafic-ultramafic complexes of the northeastern Aegean Sea, Greece, have been investigated to re-evaluate their petrogenetic evolution and tectonic setting. These complexes are: the mafic-ultramafic complex of Lesvos Island and the ophiolites of Samothraki Island and the Evros area. In order to examine these complexes in detail whole-rock major- and trace-elements as well as Sr and Nd isotopes, and minerals were analysed and U-Pb SHRIMP ages on zircons were determined. The mafic-ultramafic complex of Lesvos Island consists of mantle peridotite thrusted over a tectonic mélange containing metasediments, metabasalts and a few metagabbros. This succession had previously been interpreted as an ophiolite of Late Jurassic age. The new field and geochemical data allow a reinterpretation of this complex as representing an incipient continental rift setting that led to the subsequent formation of the Meliata-Maliac-Vardar branches of Neotethys in Upper Permian times (253 ± 6 Ma) and the term “Lesvos ophiolite” should be abandoned. With proceeding subduction and closure of the Maliac Ocean in Late Jurassic times (155 Ma) the Lesvos mafic-ultramafic complex was obducted. Zircon ages of 777, 539 and 338 Ma from a gabbro strongly suggest inheritance from the intruded basement and correspond to ages of distinct terranes recently recognized in the Hellenides (e.g. Florina terrane). Geochemical similar complexes which contain rift associations with Permo-Triassic ages can be found elsewhere in Greece and Turkey, namely the Teke Dere Thrust Sheet below the Lycian Nappes (SW Turkey), the Pindos subophiolitic mélange (W Greece), the Volcanosedimentary Complex on Central Evia Island (Greece) and the Karakaya Complex (NW Turkey). This infers that the rift-related rocks from Lesvos belong to an important Permo-Triassic rifting episode in the eastern Mediterranean. The ‘in-situ’ ophiolite of Samothraki Island comprises gabbros, sparse dykes and basalt flows as well as pillows cut by late dolerite dykes and had conventionally been interpreted as having formed in an ensialic back-arc basin. The results of this study revealed that none of the basalts and dolerites resemble mid-ocean ridge or back-arc basin basalts thus suggesting that the Samothraki ophiolite cannot represent mature back-arc basin crust. The age of the complex is regarded to be 160 ± 5 Ma (i.e. Oxfordian; early Upper Jurassic), which precludes any correlation with the Lesvos mafic-ultramafic complex further south (253 ± 6 Ma; Upper Permian). Restoration of the block configuration in NE Greece, before extensional collapse of the Hellenic hinterland and exhumation of the Rhodope Metamorphic Core Complex (mid-Eocene to mid-Miocene), results in a continuous ophiolite belt from Guevgueli in the NW to Samothraki in the SE, thus assigning the latter to the Innermost Hellenic Ophiolite Belt. In view of the data of this study, the Samothraki ophiolite represents a rift propagation of the Sithonia ophiolite spreading ridge into the Chortiatis calc-alkaline arc. The ophiolite of the Evros area consists of a plutonic sequence comprising cumulate and non-cumulate gabbros with plagiogranite veins, and an extrusive sequence of basalt dykes, massive and pillow lavas as well as pyroclastic rocks. Furthermore, in the Rhodope Massif tectonic lenses of harzburgites and dunites can be found. All rocks are spatially separated. The analytical results of this study revealed an intra-oceanic island arc setting for the Evros ophiolitic rocks. During late Middle Jurassic times (169 ± 2 Ma) an intra-oceanic arc has developed above a northwards directed intra-oceanic subduction zone of the Vardar Ocean in front of the Rhodope Massif. The boninitic, island arc tholeiitic and calc-alkaline rocks reflect the evolution of the Evros island arc. The obduction of the ophiolitic rocks onto the Rhodope basement margin took place during closure of the Vardar ocean basins. The harzburgites and dunites of the Rhodope Massif are strongly depleted and resemble harzburgites from recent oceanic island arcs. After melt extraction they underwent enrichment processes by percolating melts and fluids from the subducted slab. The relationship of the peridotites and the Evros ophiolite is still ambiguous, but the stratigraphic positions of the peridotites and the ophiolitic rocks indicate separated origin. The harzburgites and dunites most probably represent remnants of the mantle wedge of the island arc of the Rhodope terrane formed above subducted slab of the Nestos Ocean in late Middle Jurassic times. During collision of the Thracia terrane with the Rhodope terrane thrusting of the Rhodope terrane onto the Thracia terrane took place, whereas the harzburgites and dunites were pushed between the two terranes now cropping out on top of the Thracia terrane of the Rhodope Massif.

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Obesity often predisposes to coronary heart disease, heart failure, and sudden death. Also, several studies suggest a reciprocal enhancing interaction between obesity and sleep curtailment. Aim of the present study was to go deeper in the understanding of sleep and cardiovascular regulation in an animal model of diet-induced obesity (DIO). According to this, Wake-Sleep (W-S) regulation, and W-S dependent regulation of cardiovascular and metabolic/thermoregulatory function was studied in DIO rats, under normal laboratory conditions and during sleep deprivation and the following recovery period, enhancing either wake or sleep, respectively. After 8 weeks of the delivery of a hypercaloric (HC) diet, treated animals were heavier than those fed a normocaloric (NC) diet (NC: 441 ±17g; HC: 557±17g). HC rats slept more than NC ones during the activity period (Dark) of the normal 12h:12h light-dark (LD) cycle (Wake: 67.3±1.2% and 57.2 ±1.6%; NREM sleep (NREMS): 26.8±1.0% and 34.0±1.4%; REM sleep (REMS): 5.7±0. 6% and 8.6±0.7%; for NC and HC, respectively; p<0.05 for all). HC rats were hypertensive throughout the W-S states, as shown by the mean arterial blood pressure values across the 24-h period (Wake: 90.0±5.3 and 97.3±1.3; NREMS: 85.1±5.5 and 92.2±1.2; REMS: 87.2±4.5 and 96.5±1.1, mmHg for NC and HC, respectively; p<0.05 for all). Also, HC rats appeared to be slightly bradycardic compared to NC ones (Wake: 359.8±9.3 and 352.4±7.7; NREMS: 332.5±10.1 and 328.9±5.4; REMS: 338.5±9.3 and 334.4±5.8; bpm for NC and HC, respectively; p<0.05 for Wake). In HC animals, sleep regulation was not apparently altered during the sleep rebound observed in the recovery period following sleep deprivation, although REMS rebound appeared to be quicker in NC animals. In conclusion, these results indicate that in the rat obesity interfere with W-S and cardiovascular regulation and that DIO rats are suitable for further studies aimed at a better understanding of obesity comorbidities.

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Il Sorafenib è l’unica terapia sistemica approvata per l’epatocarcinoma (HCC) avanzato. Tuttavia, molti tumori sviluppano resistenze. La chemioterapia metronomica sembrerebbe avere un effetto antiangiogenetico. La Capecitabina metronomica è potenzialmente efficace nell’HCC avanzato. Lo scopo dello studio è stato valutare il comportamento di un modello murino di HCC sottoposto a Sorafenib, Capecitabina e terapia combinata, per dimostrarne un eventuale effetto sinergico. Il modello è stato creato in topi scid mediante inoculazione sottocutanea di 5 milioni di cellule HuH7. I topi sono stati suddivisi in 4 gruppi: gruppo 1 sottoposto a terapia con placebo (9 topi), gruppo 2 a Sorafenib (7 topi), gruppo 3 a Capecitabina (7 topi) e gruppo 4 a terapia combinata Sorafenib+Capecitabina (10 topi). I topi sono stati studiati al giorno 0 e 14 con ecografia B-mode e con mezzo di contrasto (CEUS). Al giorno 14 sono stati sacrificati e i pezzi tumorali sono stati conservati per l’analisi Western Blot. Un topo del gruppo 1 e 4 topi del gruppo 4 sono morti precocemente e quindi sono stati esclusi. Il delta di crescita tumorale al giorno 14 rispetto al giorno 0 è risultato di +503 %, +158 %, +462 % e +176 % rispettivamente nei 4 gruppi (p<0.05 tra i 4 gruppi, tra il gruppo 1 e 2, tra il gruppo 1 e 4, tra il gruppo 2 e 3, tra il gruppo 3 e 4). Alla CEUS non si sono evidenziate differenze statisticamente significative nei cambiamenti di perfusione tumorale al giorno 14 nei 4 gruppi. L’analisi Western Blot ha mostrato livelli di VEGFR-2 inferiori nel gruppo dei topi trattati con Sorafenib. La terapia di associazione di Sorafenib e Capecitabina non comporta un beneficio, in termini di riduzione della crescita tumorale, in un modello murino di HCC rispetto al solo Sorafenib. Inoltre, può essere sospettato un incremento di tossicità.

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