[Granuloma annulare of the photoexposed areas in two liver transplant recipients]. / Granulome annulaire des zones photo-exposées chez deux malades ayant eu une greffe hépatique.

BACKGROUND: We report two cases of generalized granuloma annulare occurring in photoexposed areas in two liver transplant recipients. CASE REPORTS: Case 1 was a 65-year-old man who had undergone liver transplantation in 1992. He was given immunosuppressive and antihypertensive therapy. Within 18 months of transplantation, he developed a confluent rash with maculae on sun-exposed areas (neck opening, nape, arms) and sparing the undershirt area. Clinical examination was normal. Skin biopsy revealed a palissade infiltrate located in the middle and upper derma, suggestive of granuloma annulare, with elastophagocytosis patterns (orcein stain and ultrastructure study). Photoexposure granuloma was diagnosed. Case 2 was a 59-year-old man who had undergone liver tranplantation in 1994. He was given immunosuppressive and antihypertensive therapy and developed within 4 months a dark rash on the neck opening and nape, sparing photoprotected areas. Histopathology revealed granuloma annulare. Elastophagocytosis was disclosed by orcein stain and the ultrastructure study. DISCUSSION: This clinical presentation of granuloma annulare in two liver transplant recipients is unusual. We discuss the clinical and histopathological patterns observed in our two cases and the relationships between granuloma annulare and immunosuppression.

[Recurrent pyogenic granuloma or Warner and Wilson-Jones syndrome]. / Granulome pyogénique récurrent ou syndrome de Warner et Wilson-Jones.

BACKGROUND: Recurrent pyogenic granuloma with multiple satellite lesions is a rare and benign condition; its diagnosis may be clinically evoked from a characteristic natural history. CASE REPORTS: Two 12 year-old boys developed multiple small cutaneous lesions following removal of pyogenic granuloma, at the periphery of the scar. A CO2 laser treatment was decided in one case, and therapeutic abstention in the other one. CONCLUSION: Our two cases completely fit with the classical features of such a condition that generally clears spontaneously. This syndrome must be known because of its "pseudo-metastatic" clinical features, which may mislead the physician.

Influence of soil substrate and ozone plus acid mist on the frost resistance of young Norway spruce.

The needles of clonal Norway spruce grown in environmental chambers on two different soils (an acidic soil 1 and a calcareous soil 2) and exposed to two levels of ozone fumigation (a low level combined with neutral mist = control, and an elevated one combined with acid mist = treatment) were analyzed for their frost hardiness. No effect of ozone was observed on either the development of frost resistance during the hardening phase or on the decrease in frost resistance during the dehardening phase. The preliminary results of Brown et al. (1987) and Barnes and Davidson (1988), which indicated that ozone treatment predisposes plants to winter injury, could thus not be confirmed. Frost resistance was, however, distinctly influenced by the content of the mineral nutrients of the soils. The pronounced K(+) deficiency of the needles of the trees growing on the neutral soil (Alps) had less effect on the development of frost resistance than did the Ca(++) and Mg(++) deficiency of the needles of the trees grown on the acidic soil 1 (Bavarian Forest). The variability of frost resistance between the different clones on soil 1 was partly attributed to fluctuations in the mineral nutrient content of the needles, rather than to a genetic predisposition.

Influence of soil substrate and ozone plus acid mist on the pigment content and composition of needles from young Norway spruce trees.

The influence of an ozone + acid mist treatment on photosynthetic pigments has been examined with the needles of the (Picea abies) clones 11, 14, 16, and 133 by spectrophotometric analysis of the total pigment extract and of single components upon HPLC separation (Part A), and in terms of a detailed pigment analysis of the 1987 and 1986 needles of clone 14 by TLC (Part B). Clone 14 had been already analysed prior to the onset of the experiment. At the end of the 14-month experiment, which incorporated frost events during a simulated winter period, neither symptoms corresponding to those of spruce Type I or IV decline, nor those of ozone damage could be observed. However, the 1986 needles of the trees on soil 1, which exhibit an adequate nutrient content, showed zonal chlorosis independently of the ozone + acid mist treatment. Analysis of variance of chlorophyll contents and needle ages showed a clear reduction to nearly 50% in the 1986 needles of clone 11, soil 1, and clone 16, soil 2. In contrast, clones 14 and 16 (soil 1) formed significantly more chlorophylls during the shorter exposure time in the 1987 flush. The detailed analysis of the individual pigment components of clone 14 needles provided no evidence for a destructive influence of the treatment on the chlorophylls, xanthophylls and beta-carotene in the two needle generations which had developed during the experiment, in spite of the distinct K deficiency of the 1986 needles of the trees on soil 2 and the common chlorosis of the needles of the trees on soil 1. The observed increase in violaxanthin content upon O(3)-treatment observed in clone 14 can be considered as an expression of the protective function of the xanthophylls against photooxidative processes. In conclusion, the observed differences in the chlorophyll and carotenoid contents are better correlated with the individual clone and soil character than with the ozone + acid mist treatment. Comparing the results of the pigment analyses of the needles the differences in the pigment concentrations reflect the N and K contents (Pfirrmann et al., 1990), which differ significantly between the clones. Thus it is not possible to pool the pigment data of all clones without considering the different nutrient levels.

Correlation of chloroplast ultrastructure and membrane lipid composition to the different degrees of frost resistance achieved in leaves of spinach, ivy, and spruce.

The leaves of «moderately hardy¼ (spinach), «very hardy¼ (ivy) and «extremely hardy¼ (spruce) plants [classification according to Levitt {1980)] show characteristic differences with respect to changes in membrane lipid composition and chloroplast ultrastructure which are correlated with the degree of the frost resistance achieved by each type of tissue during adaptation to sub-zero temperatures. Spinach leaves showed no increase in their total lipid content upon frost hardening. On the contrary, the amount of galactolipids decreased considerably, whereas that of phospholipids only slightly increased. No shift from the saturated palmitic acid to the three-fold unsaturated linolenic acid was observed. The membrane lipid content of ivy leaves and spruce needles increased to a similar extent during frost hardening. However, in contrast to spruce needles, a distinct preferential accumulation of the phospholipids was observed in ivy leaves, resulting in an increased PL/GL ratio. A considerable shift from saturated (palmitic) to unsaturated fatty acids was detected in both plants, due mainly to an increase in the proportion of linoleic acid in ivy and of linolenic acid in spruce. In spite of the considerable increase in lipid content, no increase in chloroplast number per cell could be detected in ivy leaves, although the length of the thylakoids was nearly doubled and the plastids appeared to be in a division stage: however, no real division could ever be observed. On the contrary, an increase in the number of chloroplasts and mitochondria was observed in spruce needles. Membrane augmentation became further evident by the many large invaginations of the chloroplast envelope formed when the frost-hardened leaves of ivy or spruce were exposed to sub-zero temperatures which they could just survive.

Equilibrium freezing of leaf water and extracellular ice formation in Afroalpine 'giant rosette' plants.

The water potentials of frozen leaves of Afroalpine plants were measured psychrometrically in the field. Comparison of these potentials with the osmotic potentials of an expressed cellular sap and the water potentials of ice indicated almost ideal freezing behaviour and suggested equilibrium freezing. On the basis of the osmotic potentials of expressed cellular sap, the fractions of frozen cellular water which correspond to the measured water potentials of the frozen leaves could be determined (e.g. 74% at -3.0° C). The freezing points of leaves were found to be in the range between 0° C and -0.5° C, rendering evidence for freezing of almost pure water and thus confirming the conclusions drawn from the water-potential measurements. The leaves proved to be frost resistant down to temperatures between -5° C and -15° C, as depending on the species. They tolerated short supercooling periods which were necessary in order to start ice nucleation. Extracellular ice caps and ice crystals in the intercellular space were observed when cross sections of frozen leaves were investigated microscopically at subfreezing temperatures.

On the mechanisms of frost injury and frost hardening of spruce chloroplasts.

Hill reaction and noncyclic photophosphorylation of isolated class C chloroplasts of spruce (Picea abies (L.) Karst.), as well as (14)CO2 fixation by whole needles at constant laboratory conditions proceeded at high rates during spring and early summer, declined during late summer and autumn by about 60%, remained at this level during winter, and recovered quickly in early spring. During summer, the whole needles proved to be frost labile, since after exposure to-20°C and careful thawing, fast chlorophyll degradation occurred. In addition, only photosynthetically inactive chloroplasts could be isolated from those precooled needles. On the contrary, during winter the photochemical activities of plastids from freshly harvested needles did not differ from those of artificially frozen-thawed needles. When isolated spruce chloroplasts were exposed to the same subfreezing temperatures as the whole needles, no influence of freezing on the photochemical activities was observed, irrespective of whether the plastids were isolated from frost sensitive or frost hardened needles. It is concluded that frost damage to spruce chloroplasts is due to an attack of membrane toxic compounds or lytic enzymes which were liberated upon freezing from more labile compartments. Frost hardening of the chloroplasts, as determined by the stability of chlorophyll after exposure of the needles to low temperatures, as well as by the isolation of photosynthetically active chloroplasts from such precooled needles, appeared to depend at least on 2 processes: (i) an alteration of the composition of the photosynthetically active membranes and (ii) and additional stabilization of these membranes by protecting substances. The first process was indicated by a large increase (decrease) of the capability of isolated chloroplasts for PMS-mediated photophosphorylation which accompanied natural or artificial frost hardening (dehardening). Production of cryoprotecting compounds was suggested by a significant higher stability against NaCl observed with class C chloroplasts isolated from frost hardened needles as compared to that of plastids from frost labile material. The decrease of the capability for both, the ferricyanide dependent photoreactions of the plastids and the CO2 fixation by whole needles, which was observed during the frost hardening phase, cannot be due to freezing injuries; it rather appears to be a consequence of the frost hardening process.

Seasonal changes in structure and function of spruce chloroplasts.

Seasonal changes of ultrastructure were studied by electron microscopy and by determining the chlorophyll and starch content of the plastids. Young plastids of spruce (Picea abies (L.) Karst.) first function as amyloplasts which store reserve material for the growth of the young needles. Then they develop a normal thylakoid system and produce assimilation starch during the day. In autumn, starch synthesis ceases and the plastids group together. In winter they swell and their membrane system becomes disorganized and reduced. With increasing temperatures in spring the chloroplasts recover, but then they accumulate large amounts of starch, which is not broken down during the night or even during a dark period of several days. As in the previous year they now function as amyloplasts providing reserve material for the new shoot. In summer these plastids are again converted into typical chloroplasts. The same seasonal changes of structure and function could be observed in chloroplasts from 2- or 3-year old needles. Thus these changes represent cyclic processes, which repeat each year. Features of slow aging are superimposed on to these cycles.