719 research outputs found
miR-199b, a novel tumor suppressor miRNA in acute myeloid leukemia with prognostic implications
Additional file 1: Figure S1. miR-199b-5p targets HIF-1 alpha. Transcript levels of three predicted targets of miR-199b were tested via RT-qPCR in miR-199b silenced CD34 cells and HIF-1a levels were significantly increased by anti-miR-199b
Suivi des variations spatio-temporelles du stock d'eau prÚs d'une mare endoréique au Sahel par résonance magnétique des protons et par gravimétrie
L'infiltration profonde sous les mares temporaires est la principale source de recharge des aquifÚres libres au Sahel. Au Niger semi-aride, une tomographie et un suivi RMP (résonance magnétique protonique) ainsi que plusieurs campagnes de mesures de gravimétrie absolue et relative ont été réalisés entre 2008 et 2010 pour étudier la sensibilité des deux méthodes géophysiques aux variations spatio-temporelles du stock d'eau souterrain à proximité d'une mare. Les résultats montrent une bonne cohérence et une complémentarité des méthodes, les sondages RMP étant davantage précis pour caractériser les variations verticales et horizontales du stock d'eau et la gravimétrie étant plus performante pour l'estimation des variations temporelles et/ou superficielles. (Résumé d'auteur
Subchondral chitosan/blood implant-guided bone plate resorption and woven bone repair is coupled to hyaline cartilage regeneration from microdrill holes in aged rabbit knees
SummaryObjectiveLittle is known of how to routinely elicit hyaline cartilage repair tissue in middle-aged patients. We tested the hypothesis that in skeletally aged rabbit knees, microdrill holes can be stimulated to remodel the bone plate and induce a more integrated, voluminous and hyaline cartilage repair tissue when treated by subchondral chitosan/blood implants.DesignNew Zealand White rabbits (13 or 32 months old, NÂ =Â 7) received two 1.5Â mm diameter, 2Â mm depth drill holes in each knee, either left to bleed as surgical controls or press-fit with a 10Â kDa (distal hole: 10K) or 40Â kDa (proximal hole: 40K) chitosan/blood implant with fluorescent chitosan tracer. Post-operative knee effusion was documented. Repair tissues at day 0 (NÂ =Â 1) and day 70 post-surgery (NÂ =Â 6) were analyzed by micro-computed tomography, and by histological scoring and histomorphometry (SafO, Col-2, and Col-1) at day 70.ResultsAll chitosan implants were completely cleared after 70 days, without increasing transient post-operative knee effusion compared to controls. Proximal control holes had worse osteochondral repair than distal holes. Both implant formulations induced bone remodeling and improved lateral integration of the bone plate at the hole edge. The 40K implant inhibited further bone repair inside 50% of the proximal holes, while the 10K implant specifically induced a âwound bloomâ reaction, characterized by decreased bone plate density in a limited zone beyond the initial hole edge, and increased woven bone (WB) plate repair inside the initial hole (PÂ =Â 0.016), which was accompanied by a more voluminous and hyaline cartilage repair (PÂ <Â 0.05 vs control defects).ConclusionIn a challenging aged rabbit model, bone marrow-derived hyaline cartilage repair can be promoted by treating acute drill holes with a biodegradable subchondral implant that elicits bone plate resorption followed by anabolic WB repair within a 70-day repair period
Zincalstibite-9R: the first nine-layer polytype with the layered double hydroxide structure-type
Zincalstibite-9R, a new polytype in the hydrotalcite supergroup is reported from the Monte Avanza mine, Italy. It occurs as pale blue curved disc-like tablets flattened on {001} intergrown to form rosettes typically less than 50 ÎŒm in diameter, with cyanophyllite and linarite in cavities in baryte. Zincalstibite-9R is uniaxial (â), with refractive indices Ï = 1.647(2) and Δ = 1.626(2) measured in white light. The empirical formula (based on 12 OH groups) is (Zn^(2+)_(1.09)Cu^(2+)_(0.87)Al_(0.04))_(ÎŁ2.00)Al_(1.01) (Sb^(5+)_(0.97)Si_(0.02))ÎŁ_(0.99)(OH)_(12), and the ideal formula is (Zn,Cu)_2Al(OH)_6[Sb(OH)_6]. Zincalstibite-9R crystallizes in space group R3Ä°, with É = 5.340(2), c = 88.01(2) Ă
, V = 2173.70(15) Ă
^3 and Z = 9. The crystal structure was refined to R_1 = 0.0931 for 370 unique reflections [F_o > 4Ï(F)] and R_1 = 0.0944 for all 381 unique reflections. It has the longest periodic layer stacking sequence for a layered double hydroxide compound reported to date
Hydroxyferroroméite, a new secondary weathering mineral from Oms, France
HydroxyferroromĂ©ite, ideally (Fe2+ 1.5[]0.5)Sb5+ 2O6(OH), is a new secondary mineral from the Correc d'en Llinassos, Oms, PyrĂ©nĂ©es-Orientales Department, France. HydroxyferroromĂ©ite occurs as yellow to yellow-brown powdery boxwork replacements up to about 50ÎŒm across after tetrahedrite in a sideriteâquartz matrix. No distinct crystals have been observed. The empirical formula (based on 7 (O + OH) per formula unit, pfu) is (Fe2+ 1.07Cu2+ 0.50Zn0.03Sr0.03Ca 0.01[]0.36)ÎŁ2 (Sb5+ 1.88Si0.09Al0.02As0.01)ÎŁ2 O6 ((OH)0.86 O0.14). X-ray photoelectron spectroscopy was used to determine the valence states of Sb, Fe and Cu. HydroxyferroromĂ©ite crystallises in the space group Fd3 m with the pyrochlore structure and hence is a new Fe2+ -dominant member of the romĂ©ite group of the pyrochlore supergroup. It has the unit-cell parameters: a = 10.25(3) Ă
, V = 1077(6) Ă
3 and Z = 8. A model, based on bond-valence theory, for incorporation of the small Fe2+ cation into a displaced variant of the A site of the pyrochlore structure is proposed.The attached document is the author(âsâ) final accepted/submitted version of the journal article. You are advised to consult the publisherâs version if you wish to cite from it
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