847 research outputs found
Antioxidant mesoporous Ce-doped bioactive glass nanoparticles with anti-inflammatory and pro-osteogenic activities
Mesoporous bioactive glass nanoparticles (MBGNs) are emerging biomaterials for bone repair/regeneration, considering their favorable pro-osteogenic and proangiogenic activities. To further improve their therapeutic effects, the endowment of MBGNs with additional antioxidant properties is of particular interest to target oxidative stress related to bone remodeling and diseases. To this end, we developed antioxidant cerium-containing MBGNs (Ce-MBGNs) (particle size of 100â300 ânm) by using a postimpregnation strategy to incorporate Ce, through which the shape, pore structure, and dispersity of the nanoparticles were preserved. The incorporated amount of Ce could be tailored by adjusting the concentration of the Ce precursor solution. When impregnated at a relatively low temperature (20 â°C), Ce-MBGNs containing either 1.8 or 2.8 âmol% of Ce were produced, while the formation of by-product cerium oxide nanoparticles (nanoceria) could be avoided. In both developed Ce-MBGNs, the concentration of Ce4+ was higher than that of Ce3+, while the relative molar percentage of Ce4+ was similar (âŒ74%) in both Ce-MBGNs. The obtained Ce-MBGNs were evidenced to be non-cytotoxic against fibroblasts at the concentration of 1 âmg/mL. Moreover, the incorporation of Ce into MBGNs significantly reduced the expression of oxidative stressârelated genes in macrophages (J774a.1). Particularly in the presence of pro-oxidation agents, Ce-MBGNs could downregulate the expression of oxidative stressârelated genes in comparsion with the polystyrene plates (control). When cultured with Ce-MBGNs, the expression of proinflammatory-related genes in macrophages could also be downregulated in comparsion with MBGNs and the control. Ce-MBGNs also exhibited pro-osteogenic activities through suppressing pro-osteoclastogenic responses. The obtained results highlight the great potential of the developed Ce-MBGNs in a variety of biomedical applications, particularly in treating bone defects under inflammatory conditions, considering their antioxidant, anti-inflammatory, and pro-osteogenesis activities
emission rates in absorptions at rest on Li, Li, Be, C and O
An experimental study of the reaction
on Li, Li, Be, C and O -shell nuclei is
presented. The data were collected by the FINUDA spectrometer operating at the
DANE -factory (LNF-INFN, Italy). Emission rates for the reaction in
the mentioned nuclei are measured and compared with the few existing data. The
spectra of several observables are discussed; indications of Quasi-Free
absorptions by a pair embedded in the nucleus can be obtained from
the study of the missing mass distributions.Comment: Version accepted by PR
Connective tissue anomalies in patients with spontaneous cervical artery dissection.
OBJECTIVE: To investigate the prevalence of connective tissue abnormalities in patients with spontaneous cervical artery dissections (sCeAD). METHODS: We systematically assessed clinically detectable signs of connective tissue aberration in a series of consecutive patients with sCeAD and of age- and sex-matched patients with ischemic stroke unrelated to CeAD (non-CeAD IS) by a standard examination protocol including 68 items, and performed extensive molecular investigation for hereditary connective tissue disorders in all patients with sCeAD. RESULTS: The study group included 84 patients with sCeAD (mean age, 44.5 ± 7.8 years; 66.7% men) and 84 patients with non-CeAD IS. None of the patients with sCeAD met clinical or molecular diagnostic criteria for established hereditary connective tissue disorder. Connective tissue abnormalities were detected more frequently in the group of patients with sCeAD than in the group of those with non-CeAD IS (mean number of pathologic findings, 4.5 ± 3.5 vs 1.9 ± 2.3; p < 0.001). Eighty-one patients (96.4%) in the sCeAD group had at least one detectable sign compared with 55 patients (66.7%) in the group with non-CeAD IS (p < 0.001). Skeletal, ocular, and skin abnormalities, as well as craniofacial dysmorphisms, were the clinical signs more strongly associated with sCeAD. Signs suggesting connective tissue abnormality were also more frequently represented in patients with sCeAD than in patients with traumatic CeAD (28.6%, p < 0.001; mean number of pathologic findings, 1.7 ± 3.7, p = 0.045). CONCLUSIONS: Connective tissue abnormalities are frequent in patients with sCeAD. This reinforces the hypothesis that systemic aberrations of the connective tissue might be implicated in the pathogenesis of the disease
Production of H and H with the (K,) reaction
The production of neutron rich -hypernuclei via the
(,) reaction has been studied using data collected with the
FINUDA spectrometer at the DANE -factory (LNF). The analysis of the
inclusive momentum spectra is presented and an upper limit for the
production of H and H from Li and Li, is
assessed for the first time.Comment: 11 pages, 3 figures. Accepted for publication in PL
Proton spectra from Non-Mesonic Weak Decay of p-shell Lambda-Hypernuclei and evidence for the two-nucleon induced process
New spectra from the FINUDA experiment of the Non Mesonic Weak Decay (NMWD)
proton kinetic energy for 9(Lambda)Be, 11(Lambda)B, 12(Lambda)C, 13(Lambda)C,
15 (Lambda)N and 16(Lambda)O are presented and discussed along with the
published data on 5(Lambda)He and 7(Lambda)Li. Exploiting the large mass number
range and the low energy threshold (15 MeV) for the proton detection of FINUDA,
an evaluation of both Final State Interactions (FSI) and the two nucleon
induced NMWD contributions to the decay process has been done. Based on this
evaluation, a linear dependence of FSI on the hypernuclear mass number A is
found and for the two nucleon stimulated decay rate the experimental value of
Gamma2/Gammap=0.43+-0.25 is determined for the first time. A value for the two
nucleon stimulated decay rate to the total decay rate
Gamma2/GammaNMWD=0.24+-0.10 is also extracted.Comment: 11 pages and 2 figure
A study of the proton spectra following the capture of in Li and C with FINUDA
Momenta spectra of protons emitted following the capture of in Li
and C have been measured with 1% resolution. The C spectrum is
smooth whereas for Li a well defined peak appears at about 500 MeV/. The
first observation of a structure in this region was identified as a strange
tribaryon or, possibly, a -nuclear state. The peak is correlated with a
coming from decay in flight, selected by setting momenta
larger than 275 MeV/. The could be produced, together with a 500
MeV/ proton, by the capture of a in a deuteron-cluster substructure of
the Li nucleus. The capture rate for such a reaction is (1.62\pm
0.23_{stat} ^{+0.71}_{-0.44}(sys))%/K^-_{stop}, in agreement with the existing
observations on He targets and with the hypothesis that the Li nucleus
can be interpreted as a cluster.Comment: 21 pages, 10 figures. Accepted for publication in NP
Hypernuclear spectroscopy with K at rest on Li, Be, C and O
The FINUDA experiment collected data to study the production of hypernuclei
on different nuclear targets. The hypernucleus formation occurred through the
strangeness-exchange reaction K^-_{stop} + \; ^AZ \rightarrow \; ^A_{\Lambda}Z
+ \pi^-. From the analysis of the momentum of the emerging , binding
energies and formation probabilities of Li, Be,
C and O have been measured and are here
presented. The behavior of the formation probability as a function of the
atomic mass number A is also discussed.Comment: Accepted for publication in PL
Spin-Vacancy-Induced Long-Range Order in a New Haldane-Gap Antiferromagnet
Magnetic susceptibility, high-field magnetization and inelastic neutron
scattering experiments are used to study the magnetic properties of a new S=1
quasi-1-dimensional antiferromagnet PbNi2V2O8. Inter-chain interactions are
shown to be almost, but not quite, strong enough to destroy the nonmagnetic
singlet ground state and the energy gap in the magnetic excitation spectrum.
Substituting nonmagnetic Mg (S=0) ions for Ni (S=1) induces a
magnetically ordered state at low temperatures. To our knowledge this is the
first observation of doping-induced long-range order in a Haldane-gap system.Comment: 5 pages including 4 figure
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