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1.
PS Frenette S Subbarao IB Mazo UH von Andrian DD Wagner 《Canadian Metallurgical Quarterly》1998,95(24):14423-14428
The adhesive mechanisms allowing hematopoietic progenitor cells (HPC) homing to the bone marrow (BM) after BM transplantation are poorly understood. We investigated the role of endothelial selectins and vascular cell adhesion molecule-1 (VCAM-1) in this process. Lethally irradiated recipient mice deficient in both P-and E-selectins (P/E-/-), reconstituted with minimal numbers (=5 x 10(4)) of wild-type BM cells, poorly survived the procedure compared with wild-type recipients. Excess mortality in P/E-/- mice, after a lethal dose of irradiation, was likely caused by a defect of HPC homing. Indeed, we observed that the recruitment of HPC to the BM was reduced in P/E-/- animals, either splenectomized or spleen-intact. Homing into the BM of P/E-/- recipient mice was further compromised when a function-blocking VCAM-1 antibody was administered. Circulating HPC, 14 hr after transplantation, were greatly increased in P/E-/- mice treated with anti-VCAM-1 compared with P/E-/- mice treated with just IgG or wild-type mice treated with either anti-VCAM-1 or IgG. Our results indicate that endothelial selectins play an important role in HPC homing to the BM. Optimal recruitment of HPC after lethal doses of irradiation requires the combined action of both selectins and VCAM-1 expressed on endothelium of the BM. 相似文献
2.
M Thiel C Zourelidis JD Chambers UH von Andrian KE Arfors K Messmer K Peter 《Canadian Metallurgical Quarterly》1997,29(3):160-175
Adhesion molecules on polymorphonuclear leukocytes (PMNL) play an important role in nonspecific defense mechanisms directed at invading microorganisms. When local infection, however, cannot be controlled, a systemic inflammatory response syndrome (SIRS) ensues which may progress to septic shock and multiple organ failure, these being major determinants of the patient's outcome. In the present study, the expression of beta 2-integrins and L-selectin on blood PMNL was measured on subsequent days in patients with sepsis (n = 17) and in healthy volunteers (n = 15). beta 2-Integrins and L-selectin molecules were detected by flow cytometry, using the monoclonal antibodies IB4 (anti-CD18) and Dreg200 (anti-CD62L), respectively. Adhesion molecules were determined at baseline immediately after blood collection and also 45 min after incubation of cells in vitro at body temperature to allow for spontaneous regulation. In addition, PMNL were activated by receptor-dependent and receptor-independent stimuli to characterize stimulus-specific adhesion molecule expression. In parallel with the measurement of adhesion molecules, severity of sepsis was assessed by the Elebute score. The results demonstrate significant differences in the basal, spontaneous and stimulus-induced expression of adhesion molecules between healthy volunteers, survivors (n = 11) and nonsurvivors (n = 6). Moreover, when survivors and nonsurvivors with severe sepsis (Elebute score > 12) were compared, basal expressions of both beta 2-integrins and L-selectin were significantly lower in patients who did not survive. Thus, measurement of adhesion molecules on circulating PMNL may be useful to identify septic patients at high risk for lethal outcome. 相似文献
3.
J Andrian 《Canadian Metallurgical Quarterly》1996,36(2):171-200
Suicide of people aged 25-59 years old is fastly increasing in France, especially for males, to 38.4 per 100,000 population in 1992 from 37.0 per 100,000 a decade earlier. In fact the suicide rate is decreasing among male adults having an occupation or a job (to 32.3 in 1992 from 33.8 in 1982). On the contrary, the economically inactive and the jobless are experiencing a tremendous growth in their suicide rate (to 74.9 per 100,000 population in 1992 from 60.9 a decade earlier). The trend is observed also among females aged 25-59 years old but the "employed/unemployed" gap is less pronounced. Marital status and occupational groups have also an influence upon the frequency of adult suicide. Since the work of Emile Durkheim a century ago, the profile of suicide has changed in France, due to societal upheavals. 相似文献
4.
André Andrian Padial João Carlos Nabout Tadeu Siqueira Luis Mauricio Bini José Alexandre Felizola Diniz-Filho 《Scientometrics》2010,85(1):1-12
Citation frequency has been considered a biased surrogate of publication merit. However, previous studies on this subject
were based on small sample sizes and were entirely based on null-hypothesis significance testing. Here we evaluated the relative
effects of different predictors on citation frequency of ecological articles using an information theory framework designed
to evaluate multiple competing hypotheses. Supposed predictors of citation frequency (e.g., number of authors, length of articles)
accounted for a low fraction of the total variation. We argue that biases concerning citation are minor in ecology and further
studies that attempt to quantify the scientific relevance of an article, aiming to make further relationships with citation,
are needed to advance our understanding of why an article is cited. 相似文献
5.
Andrian V.Kuchuk Fernando M.de Oliveira Pijush K.Ghosh Yuriy I.Mazur Hryhorii V.Stanchu Marcio D.Teodoro Morgan E.Ware Gregory J.Salamo 《Nano Research》2022,(3):2405-2412
Strain engineering as one of the most powerful techniques for tuning optical and electronic properties of Ⅲ-nitrides requires reliable methods for strain invest... 相似文献
6.
D. Z. Grabco O. A. Shikimaka M. Elisa B. A. Sava L. Boroica K. Pyrtsak A. Prisacaru Z. Danitsa I. Feraru D. Ursu 《Surface Engineering and Applied Electrochemistry》2012,48(4):365-374
The microstructure, as well as the mechanical and thermal properties, of phosphate glasses (PhGs) doped with rare earth elements (REEs), namely, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, and Yb, were studied in the present paper. The strength parameters of the PhGs and their dependence on the load value modification were estimated by the dynamic indentation method. Three specific stages were revealed in the deformation process, including nano-, submicro-, and microdeformation. The factors responsible for each stage were determined. It was shown that the strength properties (Young’s modulus and hardness) and the thermal characteristics (the lower and upper annealing temperature, the softening temperature, and the vitrification temperature) exhibit no evident relationship with the atomic mass and ionic radius of an REE. An assumption was made that the elastic and plastic properties of PhGs can be determined by the internal structure of the glasses. 相似文献
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8.
Nadiia Korsunska Larysa Khomenkova Oleksandr Kolomys Viktor Strelchuk Andrian Kuchuk Vasyl Kladko Tetyana Stara Oleksandr Oberemok Borys Romanyuk Philippe Marie Jedrzej Jedrzejewski Isaac Balberg 《Nanoscale research letters》2013,8(1):273
Silicon-rich Al2O3 films (Six(Al2O3)1−x) were co-sputtered from two separate silicon and alumina targets onto a long silicon oxide substrate. The effects of different annealing treatments on the structure and light emission of the films versus x were investigated by means of spectroscopic ellipsometry, X-ray diffraction, micro-Raman scattering, and micro-photoluminescence (PL) methods. The formation of amorphous Si clusters upon the deposition process was found for the films with x ≥ 0.38. The annealing treatment of the films at 1,050°C to 1,150°C results in formation of Si nanocrystallites (Si-ncs). It was observed that their size depends on the type of this treatment. The conventional annealing at 1,150°C for 30 min of the samples with x = 0.5 to 0.68 leads to the formation of Si-ncs with the mean size of about 14 nm, whereas rapid thermal annealing of similar samples at 1,050°C for 1 min showed the presence of Si-ncs with sizes of about 5 nm. Two main broad PL bands were observed in the 500- to 900-nm spectral range with peak positions at 575 to 600 nm and 700 to 750 nm accompanied by near-infrared tail. The low-temperature measurement revealed that the intensity of the main PL band did not change with cooling contrary to the behavior expected for quantum confined Si-ncs. Based on the analysis of PL spectrum, it is supposed that the near-infrared PL component originates from the exciton recombination in the Si-ncs. However, the most intense emission in the visible spectral range is due to either defects in matrix or electron states at the Si-nc/matrix interface. 相似文献
9.
Sanda Bucatariu Gheorghe Fundueanu Irina Prisacaru Mihaela Balan Iuliana Stoica Valeria Harabagiu Marieta Constantin 《Journal of Polymer Research》2014,21(11):1-12
Thermoresponsive colloidal microgels were prepared by precipitation copolymerization of N-isopropylacrylamide (NIPAM) and N-hydroxyethylacrylamide (HEAM) with various concentrations of a cross-linker in the presence of an anionic surfactant, sodium dodecylsulphate (SDS). The volume phase transition temperature (VPTT) of the prepared microgels was studied by dynamic light scattering (DLS), ultraviolet–visible spectroscopy (UV–vis) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. In addition, atomic force microscopy (AFM) was used to characterize the polydispersity and morphology of the microgels. Results indicated that poly(NIPAM-co-HEAM) microgels are spherical and monodisperse. VPTTs of microgels determined by DLS and UV–vis methods are almost the same and very close to the human body temperature, presenting the microgels as candidates for biomedical application. The temperature at which the phase transition occurred is nearly independent of the cross-linking density, whereas the transition range is deeply influenced by temperature. Also, the SDS concentration was increased to decrease the average hydrodynamic size of the microgels, due to the electrostatic repulsion between the charged particles during the polymerization process. 1H-NMR spectra of the microgels show a decrease in peak intensity with an increased temperature due to a reduction in molecular mobility of the polymer segments. Release rates of propranolol from microgels are deeply influenced by temperature; below the VPTT at 25 °C, the drug is rapidly released at a rate comparable to that of a free drug, whereas above the VPTT (37 and 42 °C), a fraction of the drug is mechanically expulsed in the first five min, followed by a prolonged release. 相似文献