274 research outputs found
Eosinophilic granulomatosis with polyangiitis (EGPA) and PRES: a case-based review of literature in ANCA-associated vasculitides
Eosinophilic granulomatosis with polyangiitis (EGPA) is a small-sized vessel systemic necrotizing vasculitis and belongs to the family of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides. The involvement of central nervous system in this condition is pretty rare. Posterior reversible encephalopathy syndrome (PRES) is a clinical and radiological entity described for the first time by Hinchey et al. (N Engl J Med 334(8):494-500, 1996) and characterized by MRI findings of reversible subcortical vasogenic edema predominantly in the white matter of posterior cerebral lobes. There are few case reports describing the concurrence of PRES with ANCA-associated vasculitides. We describe a case of PRES in a patient with a diagnosis of EGPA with a concise review of the literature. The exact cause of this syndrome is unknown. It has been related to eclampsia, drug-induced hypertension, renal insufficiency and also to rheumatologic diseases. Endothelial injury, hypertension and immunosuppressive medications can compromise the regulation of cerebral blood flow. In ANCA-associated vasculitides, patients presenting with symptoms of PRES represent a challenge to treatment with immunosuppressive medications. However, since an inflammatory process might be implicated, judicious use of these agents along with tight control of blood pressure and a supportive therapy may contribute to the resolution of the encephalopathic syndrome treating at the same time other manifestation related to the rheumatologic disease. Larger clinical studies are warranted to optimize the management of vasculitis-associated PRES
Mechanistic Insight into the Catechol Oxidase Activity by a Biomimetic Dinuclear Copper Complex
The biomimetic catalytic oxidation of 3,5-ditert-
butylcatechol by the dicopper(II) complex of the
ligand a,a¢-bis{bis[1-(1¢-methyl-2¢-benzimidazolyl)
methyl]amino}-m-xylene in the presence of dioxygen has
been investigated as a function of temperature and pH in
a mixed aqueous/organic solvent. The catalytic cycle
occurs in two steps, the first step being faster than the
second step. In the first step, one molecule of catechol is
oxidized by the dicopper(II) complex, and the copper(II)
centers are reduced. From the pH dependence, it is deduced
that the active species of the process is the
monohydroxo form of the dinuclear complex. In the
second step, the second molecule of catechol is oxidized
by the dicopper(I)-dioxygen complex formed upon
oxygenation of the reduced complex. In both cases,
catechol oxidation is an inner-sphere electron transfer
process involving binding of the catechol to the active
species. The binary catechol-dicopper(II) complex
formed in the first step could be characterized at very
low temperature (90 C), where substrate oxidation is
blocked. On the contrary, the ternary complex of dicopper(
I)-O2-catechol relevant to the second step does
not accumulate in solution and could not be characterized,
even at low temperature. The investigation of the
biphasic kinetics of the catalytic reaction over a range of
temperatures allowed the thermodynamic (DH and DS)
and activation parameters (DH „ and DS „ ) connected
with the key steps of the catecholase process to be
obtained
A case of tension-type headache in fibromyalgia
Ref.: Ms. No. TJHP-D-10-00029R1
A 57 years-old-woman was admitted to our ward for a daily tension-type headache, non responsive to usual pharmacological treatment. Five years ago she underwent a hysterectomy. Since then, she referred muscular rigor of the neck and the shoulder girdle, intense constrictive pain localized in the occipital spine. She also reported weakness of the upper and lower limbs, tingling, tremors and difficulties in walking and climbing. She referred widespread pain, unusually severe, above all at joints and muscles, without any sign of inflammation at clinical examination. The diagnosis of a connective tissue was excluded, remaining the diagnosis of tension-type headache in Fibromyalgia the most probable one. The patient has been treated with antidepressants, anxiolytics, and antiepileptic drugs with improvement of the symptoms
THE STRAIT OF MESSINA: A KEY AREA FOR PELAGIA NOCTILUCA (CNIDARIA, SCYPHOZOA)
The Strait of Messina is certainly a focal area for the biological cycle of the jellyfish
Pelagia noctiluca in the Western Mediterranean Sea. By means of both original and
literature data, a conceptual model outlining the biological cycle of this species is
proposed. P. noctiluca reproduces from late winter to late spring in the Aeolian Island
Archipelago. From late spring to early summer, currents transport newly produced young
individuals (20-30 mm bell diameter) eastwards, towards the Strait. The Strait of Messina
ecosystem is not a suitable reproduction area for its intense hydrodynamism that would
surely lead to a very low reproductive success due to gamete dispersion. This area,
however, represents an optimal site for growth, due to its intensive primary and secondary production, but also for an optimal temperature range, lower in summer and
higher in winter in respect to the surrounding basins. Pelagia remains all the summer
inside the Strait, increasing in bell diameter (50-70 mm) and biomass. Subsequently, in
late summer-early autumn, the mature specimens, taking advantage of a typical autumnal
downwelling transport, move to deep Tyrrhenian waters where overwinter, to upwell in
the Aeolian Archipelago by late winter to start a new cycle
Nocturnal cough and difficulty breathing during exertion in a young boy: Do not miss the forest for the trees
No abstract avaiable
Synthetic Crysotile Nano-Crystals as a Reference Standard to Investigate Surface-Induce Serum Albumin Structural Modifications
Geoinspired synthetic chrysotile, which represents an ideal asbestos reference standard, has been utilized to investigate homomolecular exchange
of bovine serum albumin (BSA), the major plasma protein, between the adsorbed and dissolved state at the interface between asbestos
fibers and biological medium. FTIR spectroscopy has been used to quantify BSA structural modifications due to surface adhesion on chrysotile
fibers as a function of the surface coating extent. Circular dichroism spectroscopy has been used to investigate the adsorption/desorption equilibrium
through analysis of the BSA structural perturbations after protein desorption from chrysotile surface. Data results show clearly that in
the solid state BSA modifications are driven by surface interaction with the substrate, following a bimodal adsorption evidenced by two different
binding constants. On the other hand, BSA desorbed in solution is able to rearrange, in the lack of substrate, although keeping irreversible
modifications with respect to the native species. The lack of regaining its native structure certainly affects albumin interaction with biological
environment. The present investigation on the stoichiometric synthetic geoinspired chrysotile nanocrystals is the first approach toward a deeper
attempt to use standard synthetic chrysotile reference samples in mimicking the behavior of asbestos fibers and allows to better understand their
interaction with a biological environment
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