A Zohair | PubMed Health

PubMed1991

[Severe subglottic hemangioma in the infant: corticotherapy, intubation or surgery?].

In the case of sub-glottic hemangioma, with serious immediate or cortico-resistant dyspnea, it is not always possible to wait for the growth of the laryngo-tracheal skeleton and the spontaneous involution of the angioma. On the basis of a series of 25 cases, we propose in these serious forms the following therapeutic escalation: very high dose corticotherapy, with betamethasone at 0.12 to 0.48 mg/kg/day for 15 days, followed by a degressive treatment over 6 weeks to 3 months; intubation to overcome a difficult stage in the event of aggravation of the angioma with a rhinopharyngitis. Embolization and the use of the laser proved unsatisfactory in the extensive forms of angiomas. In the event of failure of the preceding treatment, we perform a tracheotomy, the duration of which can be reduced by the surgical exeresis of the angioma with a widening of the larynx.

Adrenal Cortex Hormones↗

PubMed1989

Interaction between complement subcomponent C1q and bacterial lipopolysaccharides.

The heptose-less mutant of Escherichia coli, D31m4, bound complement subcomponent C1q and its collagen-like fragments (C1qCLF) with Ka values of 1.4 x 10(8) and 2.0 x 10(8) M-1 respectively. This binding was suppressed by chemical modification of C1q and C1qCLF using diethyl pyrocarbonate (DEPC). To investigate the role of lipopolysaccharides (LPS) in this binding, biosynthetically labelled [14C]LPS were purified from E. coli D31m4 and incorporated into liposomes prepared from phosphatidylcholine (PC) and phosphatidylethanolamine (PE) [PC/PE/LPS, 2:2:1, by wt.]. Binding of C1q or its collagen-like fragments to the liposomes was estimated via a flotation test. These liposomes bound C1q and C1qCLF with Ka values of 8.0 x 10(7) and 2.0 x 10(7) M-1; this binding was totally inhibited after chemical modification of C1q and C1qCLF by DEPC. Liposomes containing LPS purified from the wild-strain E. coli K-12 S also bound C1q and C1qCLF, whereas direct binding of C1q or C1qCLF to the bacteria was negligible. Diamines at concentrations which dissociate C1 into C1q and (C1r, C1s)2, strongly inhibited the interaction of C1q or C1qCLF with LPS. Removal of 3-deoxy-D-manno-octulosonic acid (2-keto-3-deoxyoctonic acid; KDO) from E. coli D31m4 LPS decreases the binding of C1qCLF to the bacteria by 65%. When this purified and modified LPS was incorporated into liposomes, the C1qCLF binding was completely abolished. These results show: (i) the essential role of the collagen-like moiety and probably its histidine residues in the interaction between C1q and the mutant D31m4; (ii) the contribution of LPS, particularly the anionic charges of KDO, to this interaction.

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