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Notes: In France the alteration of species-rich grasslands is due mainly to agriculture and civil engineering projects (roadways, dams, ski resorts, etc.). The restoration of such ecosystems has been tested in many regions and after many sorts of degradation. According to the level of initial degradation, different responses can be envisioned. Some variations are presented of a general model of restoration and rehabilitation: (1) rejuvenation of fallow land by grazing with rustic animal breeds in wetlands or chalk grasslands in south and northwestern France, (2) restoration by recovery of extensive agricultural management in intensive agricultural areas such as the Rhône or Meuse Valleys, and (3) rehabilitation by appropriate ecological engineering carried out in grasslands degraded by intensification, ski-track, or civil engineering installations. Despite some positive results, these undertakings have not always had the expected effects and therefore should not provide alibis for the destruction of natural grasslands. In general, the success of such undertakings depends on the maintenance in the surrounding areas of protected seed source reservoirs and on the persistence of a diversified landscape pattern permitting connectivity between these seed sources and the restoration or rehabilitation sites.

Notes: 1. The application of functional ecology models to aquatic plants often relies on morphological and life-history traits which may reflect, in part, the phenotypic plasticity displayed by aquatic plants. The present study was designed to evaluate the use of physiological traits, such as nutrition patterns, to describe aquatic plant strategies along a gradient of increasing resource availablity.2. Taking phosphorus (P) as an example, nutrition-use efficiencies were evaluated in five species, through the P-content in plant tissues, the variations in P-content according to nutrient availability and the perenniality of P-storage. Plasticity in P-storage was also investigated in Ranunculus peltatus, a morphologically highly plastic species.3. In 2001, P-content was analysed in Callitriche hamulata, C. obtusangula, C. platycarpa, Elodea nuttallii and R. peltatus tissue samples. These five species were sampled at nine different sites in streams along an increasing resource gradient in the Northern Vosges Biosphere Reserve (NE France). Variations of P-content in the roots, stems and dissected and floating leaves of R. peltatus were also studied.4. Only C. platycarpa and R. peltatus were found to occur in low nutrient availability conditions. Callitriche hamulata, C. obtusangula and E. nuttallii were restricted to mesotrophic and eutrophic sites. The highest nutrient-use efficiency was found for E. nuttallii which was able to adapt its P-storage to varying resource availabilities. Ranunculus peltatus was able to store high concentrations of P, but its P-integration within the vegetative structure was less efficient under eutrophic conditions. Callitriche spp. appeared to have relatively low nutrient-use efficiencies, although C. obtusangula displayed a high P-content. While P was stored preferentially in roots in R. peltatus populations occurring in nutrient-rich sites, there was no particular P-storage organ for populations from nutrient-poor sites.5. On the basis of P-usage, R. peltatus and E. nuttallii presented competitor traits, C. hamulata and C. platycarpa displayed stress-tolerant nutrient signatures and for C. obtusangula, ruderal or competitor characteristics dominated. The use of physiological traits, such as nutrition patterns, may provide valuable, complementary information about aquatic plant strategies, independent from the influence of morphological trait plasticity often displayed by these plants.

Notes: Extraskeletal Ewing's sarcoma has been recognized as being histologically indistinguishable from Ewing's sarcoma of bone. Although the occurrence of extraosseous Ewing's sarcoma in deep soft tissues has been well described, such cutaneous lesions arc rare. We report the clinical history, histopathologic findings, and results of ultrastructural study of this rare variant occurring in a 12-year-old girl. She presented with a dermal and subcutaneous tumor of the left third toe, without osseous involvement. The lesion was composed of masses of round-oval cells, with perilobular fibrosis, focal hemorrhage, ill-defined pale cytoplasm containing glycogen, and absent pericellular reticulin. Ultrastructural study showed a monotonous cell population, with focal thickening of apposing membranes, high nuclear/cytoplasmic ratio, copious intracytoplasmic glycogen, and paucity of organ cells except mitochondria. We present this case along with discussion of the literature and problems concerning differential diagnosis of small cell malignancies in the skin.

Notes: Immune spreading to multiple intracellular antigens is likely to be of primary importance in organ-specific and systemic autoimmune diseases. A number of mechanisms by which immune spreading may occur from only a single autoreactive epitope have been proposed. Search for an initiator or early epitope thus represents an important area of investigation. For example, many studies have focused on the identification of epitopes recognized by the antibodies from both patients with systemic lupus erythematosus (SLE) and lupus-prone mice. Recently, an autoepitope present in the 70K U1 ribonucleo protein (RNP) and recognized by CD4+ T cells from lupus mice has also been identified. Here, we analyze the results of B- and T-cell-epitope mapping studies of several RNPs present in the spliceosome and propose a model of epitope spreading. In this model, a consensus sequence (the RNP motif) conserved in many nuclear, nucleolar and cytoplasmic antigens, might play a role as ‘driver’ epitope. This hypothesis is based on the observation that this sequence is recognized by CD4+ T cells from lupus mice and is often targeted by autoantibodies, very early during the course of the disease. Targeting this region that is repeated in different self-antigens, might represent an interesting strategy to interfere with the continuous T-cell stimulation and exposure to specific antigens.

Notes: Three macaques infected with SHIV-IIIB and expressing the shared 1F7-idiotypic marker on antibodies against HIV-1 gp120, were injected intravenously with 1F7 monoclonal antibodies (MoAb). As controls, a SHIV-IIIB-infected macaque was injected with a HIV-unrelated mouse monoclonal isotype antibody (TEPC-183) and two healthy, noninfected macaques were injected with MoAb 1F7. 1F7-id-expressing antibodies against gp120-IIIB decreased in two of the three MoAb 1F7-treated macaques and then rebounded. Importantly, antibodies binding to envelope proteins of heterologous HIV-1 strains MN, CM, and SF2, which were low or not detectable before the MoAb 1F7 treatment, increased rapidly following MoAb inoculations in all three 1F7 MoAb treated macaques, but not in the macaque injected with control MoAb TEPC-183. Newly arising antibodies reacting with heterologous virus, i.e. HIV-1 gp120-MN, SF2, and CM did not express 1F7-id. Surprisingly, significant increases of antibodies were also observed in the 1F7-inoculated macaques' antibodies directed to non-HIV antigens (DNP, peptides and BSA). The noninfected control animals did not produce antibodies to these antigens despite MoAb 1F7 treatment. These data show that the MoAb 1F7 injections of chronically SHIV-IIIB-infected macaques resulted in idiotype-specific clonal suppression with broadening the antibody response to HIV envelope proteins.

Notes: The clinical, histopathological, and immunophenotypic characteristics of four cases of malignancy associated multicentric reticulohistiocytosis (MMR) and one case each of diffuse cutaneous reticulohistiocytosis (OCR) and isolated reticulohistiocytoma (IR). are reviewed. In all four cases of MMR the cutaneous lesions and joint manifestations were judged to be concurrent with the diagnosis of malignancy. Malignancies observed included one case each of pancreatic adenocarcinoma, squamous cell carcinoma of the lung, metastatic melanoma and intraperitoneal grade 4 mucinous adenocarcinoma of uncertain origin.Histologically, all six cases demonstrated the typical changes of a diffuse histiocytic and multinucleated giant cell infiltrate with ground-glass cytoplasm, predominantly in the upper dermis. Immunohistochemical investigation revealed strong cytoplasmic staining with KP-1 (CD68) in all six cases. Prominent membrane staining was noted with leucocyte common antigen (CD45) in four cases (three MMR and one fR), and CD3 in four cases (three MMR and one IR). Weak membrane staining with Leu 22 (CD43) was noted in two MMR cases. UCHL-1 (CD45RO), L26 (CD20), S-100 and BerH2 stains were all uniformly negative. A prominent number of perilesional factor XIIIa-positive dermal dendrocytes were noted in the single case of IR, in contrast with the other five cases.We conclude that MMR, DCR and IR are histopathologically and immunohistochemically similar. The pattern of immunoreactivity observed is consistent with a monocyte-macrophage origin of the infiltrating tumour cells. We emphasize the paraneoplastic association of multicentric reticulohistiocytosis, which we have observed in four of 13 such cases (31%) evaluated at our institution.