Two Norway spruce (Picea abies Karst.) clones, one resistant and the other susceptible to m a s inoculation with Ophiostoma polonicum Siem., were compared with regard to their phenolic compositions and chalcone synthase (CHS) and stilbene synthase activities of their phloem before and at 6 and 1 2 d after artificial inoculation with sterile malt agar or O. polonicum. In unwounded phloem, the resistant clone differed from the susceptible clone by the presence of taxifolin glycoside, lower concentrations of stilbene glycosides, and higher CHS activity. After inoculation, (+)-catechin concentration and CHS activity dramatically increased around the wound, particularly in the resistant clone. Stilbene synthase activity also increased, but more slowly and to a lower level, whereas the concentrations of stilbenes remained stable. Tanning ability decreased in the susceptible clone, whereas it remained stable in the resistant one. It is proposed that the induced phenolic response of Norway spruce phloem consists of an activation of the phenolic pathway, finally leading to tannins and insoluble polymers. It is suggested that resistance to O. polonicum depends on the ability of the tree to easily activate the flavonoid pathway.
The S-adenosyl-l-methionine:pinosylvin-O-methyltransferase (PMT) 2 gene was sequenced from Scots pine (Pinus sylvestris). The open reading frame is arranged in two exons spaced by one 102-bp intron. Promoter regulatory elements such as two "CAAT" boxes and one "TATA" box were identified. Several cis-regulatory elements were recognized: stress-responsive elements (Myb-responsive elements) as well as G, H, and GC boxes. Moreover, elicitor-responsive elements (W boxes) and a sequence resembling the simian virus 40 enhancer core were found. In phloem and needles of control trees, the transcripts of stilbene synthase (STS) and PMT were hardly detectable. Increased ozone fumigation up to 0.3 L L Ϫ1 enhanced the transcript level of STS and PMT in needles but not in healthy phloem. Wounding, e.g. mock inoculation, of stem-phloem was characterized by a transient increase in STS and PMT transcripts, which was more pronounced in the case of fungal inoculation. Combination of fungal-challenge or mock treatment with ozone resulted in a positive interaction at 0.3 L L Ϫ1 . Scots pine stilbene formation appeared to be induced via STS and PMT gene expression upon ozone and fungal stress as well as wounding. The broad stress-responsiveness is in agreement with the range of various cis-acting elements detected in the STS and PMT promoters.
Neurofibromatosis 1 (NF1) is a common disease which is a source of various multisystemic manifestations related either to the accumulation of neurofibromas or to specific developmental abnormalities. The neurofibroma is the hallmark lesion of NF1 and develops from peripheral nerves. However, to date, the description of peripheral neuropathies of NF1 has not been investigated. To examine this question, we have evaluated 688 NF1 patients for the presentation, prognosis and associated morbidity of peripheral neuropathies in two hospital-based series. We collected 18 patients (four women and 14 men) with diffuse peripheral neuropathy (2.3%). Eight patients had a paucisymptomatic or an asymptomatic neuropathy detected only on electrophysiological study, two had minor sensory manifestations, five had moderate motor and sensory manifestations and three had severe motor and sensory manifestations. Superimposed radicular changes were observed in seven cases. Two patients had a subacute and 16 a chronic polyneuropathy. Fourteen patients had a demyelinating neuropathy with either severe axonal changes (three), moderate or minor axonal changes (four) or no axonal changes (seven). Four patients had axonal neuropathies. There was a strong association between the presence of a peripheral neuropathy and large root diffuse neurofibromas (P < 0.03) and subcutaneous neurofibromas (P < 0.0001). Severe morbidity and mortality of patients with NF1 and peripheral neuropathies was 50%, much higher than what is observed in the general population of patients with NF1, and 100% in patients with the most severe symptoms and electrophysiological changes (demyelination with severe axonal features). Four patients out of 18 (22%) developed a malignant peripheral nerve sheath tumour (MPNST), a much higher proportion than in the whole population of NF1. Two patients died. Peripheral neuropathy constitutes a potentially severe complication in patients with NF1 associated with a frequent morbidity related to spinal complications and MPNSTs. Association of proximal large neurofibromas, peripheral neuropathies and subcutaneous neurofibromas may constitute a phenotype of NF1 with a severe prognosis.
The aim of this stuciy was to uivestigate the temporal changes in Norway-spruce {Picea abies) phloem phenolics during wound-mduced response. Two Norway spruces were inoculated with Opbiostoma polonicum and sterile agar; unwounded phloem was simultaneously tested as control. Both unwounded and inoculated phloem were then sampled 6, 11, 21, 30, and 60 days later. Monophenols were analysed by HPLC, and the tanning capacity of the phloem extracts was estimated from their ability to precipitate proteins. The response to inoculation was eharaeterized by radical changes in the phloem phenolic composition. Initially, an increase in (+)-catechin concentration was obsei^ved, concomitant with a slow decrease m both glycoside concentrations and tanning capacity. After day 6, this decrease was accelerated in the event of fungus inoculation. The appearance of aglyeones did not take place during the decrease in glycosides, but was delayed. The phenolic response of Noi"way-spiuce phloem to inoculation is modulated by the presence of the fungus and is focused on the formation of insoluble compounds.
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