1,086 research outputs found
Oxidative, multistep activation of the noncanonical NF-kappa B pathway via disulfide Bcl-3/p50 complex
No full textButhionine sulfoximine ( BSO) is a well-known inhibitor of glutathione synthesis, producing slow glutathione ( GSH) depletion and oxidative stress; some "responder" cells avoid BSO-induced death by trans-activating the prosurvival protein Bcl-2. Here we show that BSO activates a noncanonical, inhibitory NF-kappa B- and p65-independent NF-kappa B pathway via a multistep process leading to the up-regulation of Bcl-2. The slow BSO-induced GSH depletion allows separation of two redox-related phases, namely, early thiol disequilibrium and late frank oxidative stress; each phase contributes to the progressive activation of a p50-p50 homodimer. The early phase, coinciding with substantial thiol depletion, produces a cytosolic preparative complex, consisting of p50 and its interactor Bcl-3 linked by interprotein disulfide bridges. The late phase, coinciding with reactive oxygen species production, is responsible, probably via p38 activation, for nuclear targeting of the complex and trans-activation of Bcl-2. Cristofanon, S., Morceau, F., Scovassi, A. I., Dicato, M., Ghibelli, L., Diederich, M. Oxidative, multistep activation of the noncanonical NF-kappa B pathway via disulfide Bcl-3/p50 complex. FASEB J. 23, 45-57 ( 2009
Supramolecular [60]fullerene chemistry on surfaces
No full textThis critical review documents the exceptional range of research avenues in [60]fullerene-based monolayers showing unique and spectacular physicochemical properties which prompted such materials to have potential applications in several directions, ranging from sensors and photovoltaic cells to nanostructured devices for advanced electronic applications, that have been pursued during the past decade. It illustrates how progress in covalent [60]fullerene functionalisation led to the development of spectacular surface-immobilised architectures, including dyads and triads for photoinduced electron and energy transfer, self-assembled on a wide variety of surfaces. All of these molecular assemblies and supramolecular arrays feature distinct properties as a consequence of the presence of different molecular units and their spatial arrangement. Since the properties of [60]fullerene-containing films are profoundly controlled by the deposition conditions, substrate of adsorption, and influenced by impurities or disordered surface structures, the progress of such new [60]fullerene-based materials strongly relies on the development of new versatile and broad preparative methodologies. Therefore, the systematic exploration of the most common approaches to prepare and characterise [60]fullerene-containing monolayers embedded into two- or three-dimensional networks will be reviewed in great detail together with their main limitations. Recent investigations hinting at potential technological applications addressing many important fundamental issues, such as a better understanding of interfacial electron transfer, ion transport in thin films, photovoltaic devices and the dynamics associated with monolayer self-assembly, are also highlighted
New lichens and lichen records from Papua New Guinea : with the description of Crustospathula, a new genus in the Bacidiaceae
No full textSeveral lichen species are reported from the first time from New Guinea, based on material collected by the author in 1995. The following new taxa are described: Crustospathula cartilaginea gen. et spec. nov., Pseudopyrenula serusiauxii spec. nov. and Trypethelium galligenum spec. nov. Psoroma papuana Aptroot & Diederich nom. nov. is proposed as new name for Psoroma pannarioides Aptroot & Diederich
Pseudoconvex domains: Diederich - Fornaess index and the invariant metrics near the boundary points
No full textThis Thesis deals with some problems related to the pseudoconvex domain.
The first chapter presents some results on the theory on plurisubharmonic defining function. From the relation of the Diederich - Fornaess index with the estimate for \bar\partial - Neumann operator on the pseudoconvex domain, the author generalize the results by finding the index and its applications on general q-pseudoconvex domains.
The second part of the thesis is studying the invariant metrics, more precise, the Kobayashi metric, near infinite boundary points. Diederich and Fornaess on showed us how fast the Kobayashi metric of a point go to infinity when it comes near the boundary of a pseudoconvex domain that has real analytic boundary. Remove that cruel assumption, the author prove the result in more general class domains. From the estimate for the Kobayashi metric, there is a proper holomorphic mapping theorem and have a Holder estimate for it
Differential expression of nitric oxide synthases (eNOS and iNOS) in porcine aortic endothelial cells during LPS-induced apoptosis.
No full textAsciminib mitigates DNA damage stress signaling induced by cyclophosphamide in the ovary
No full textCancer treatments often have adverse effects on the quality of life for young women. One of the most relevant negative impacts is the loss of fertility. Cyclophosphamide is one of the most detrimental chemotherapeutic drugs for the ovary. Cyclophosphamide may induce the destruction of dormant follicles while promoting follicle activation and growth. Herein, we demonstrate the in vivo protective effect of the allosteric Bcr-Abl tyrosine kinase inhibitor Asciminib on signalling pathways activated by cyclophosphamide in mouse ovaries. Besides, we provide evidence that Asciminib did not interfere with the cytotoxic effect of cyclophosphamide in MCF7 breast cancer cells. Our data indicate that concomitant administration of Asciminib mitigates the cyclophosphamide-induced ovarian reserve loss without preventing the anticancer potential of cyclophosphamide. Altogether these observations are relevant for the development of effective ferto-protective adjuvants to preserve the ovarian reserve from the damaging effect of cancer therapies
Two complexes containing 19-atom chains linking metal centres
No full textCopyright © 2009 Académie des sciences. Published by Elsevier Masson SAS
The first example of a complex containing a C
19
chain, {Co
3
(μ-dppm)(CO)
7
}{μ
3
-C(C≡C)
9
}{W(CO)
3
Cp}, has been prepared in 22% yield from the Pd(0) / Cu(I)-catalysed reaction between I(C≡C)
3
I, W{C≡CC≡CAu(PPh
3
)}(CO)
3
Cp and Co
3
{μ
3
-C(C≡C)
4
Au(PPh
3
)}(μ-dppm)(CO)
7
. Other products also formed include {Co
3
(μ-dppm)(CO)
7
}{μ
3
-C(C≡C)
6
}{W(CO)
3
Cp} (32%), {Co
3
(μ-dppm)(CO)
7
}
2
{μ
3
:μ
3
-C(C≡C)
x
C} [
x
= 8 (6%) and 11 (5%)], containing respectively C
13
, C
18
and C
24
chains, and {W(CO)
3
Cp}
2
{μ-(C≡C)
x
} (
x
= 4, 7) (traces). A second example of a 19-atom chain is found in Hg{(C≡C)
4
C[Co
3
(μ-dppm)(CO)
7
]}
2
, obtained in 24% yield from the reaction between Hg(OAc)
2
and Co
3
{μ
3
-C(C≡C)
4
SiMe
3
}(μ-dppm)(CO)
7
in the presence of NaOMe.
Michael I. Bruce, Brian K. Nicholson and Natasha N. Zaitsev
A two-dimensional porphyrin-based porous network featuring communicating cavities for the templated complexation of fullerenes
No full textSupramolecular nanostructuring of silver surfaces via self-assembly of [60]fullerene and porphyrin modules
No full textRecent achievements in our laboratory toward the "bottom-up" fabrication of addressable multicomponent molecular entities obtained by self-assembly of C-60 and porphyrins on Ag(100) and Ag(111) surfaces are described.. Scanning tunneling microscopy (STM) studies on ad-layers constituting monomeric and triply linked porphyrin modules showed that the molecule:, self-organize into ordered supramolecular assemblies, the ordering of which is controlled by the porphyrin chemical structure, the metal substrate, and the surface coverage. Specifically, the successful preparation of unprecedented two-dimensional porphyrin-based assemblies featuring regular pores on Ag(111) surfaces has been achieved. Subsequent co-deposition of C-60 molecules on top of the porphyrin monolayers results in selective self-organization into ordered molecular hybrid bilayers, the organization of which is driven by both fullerene coverage and porphyrin structure. In all-ordered fullerene-porphyrin assemblies, the C-60 guests organize, unusually, into long chains and/or two-dimensional arrays. Furthermore, sublimation of C-60 on top of the porous porphyrin network reveals the selective long-range inclusion of the fullerene guests within the hosting cavities. The observed mode of the C-60 self-assembly originates from a delicate equilibrium between substrate-molecule and molecule-molecule interactions involving charge-transfer processes and conformational reorganizations as a consequence of the structural adaptation, of the fullerene-porphyrin bilayer
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