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High levels of phenotypic plasticity are thought to be inherently costly in stable or extreme environments, but enhanced plasticity may evolve as a response to new environments and foster novel phenotypes. Heliosperma pusillum forms glabrous alpine and pubescent montane ecotypes that diverged recurrently and polytopically (parallel evolution) and can serve as evolutionary replicates. The specific alpine and montane localities are characterized by distinct temperature conditions, available moisture, and light. Noteworthy, the ecotypes show a home-site fitness advantage in reciprocal transplantations. To disentangle the relative contribution of constitutive versus plastic gene expression to altitudinal divergence, we analyze the transcriptomic profiles of two parallely evolved ecotype pairs, grown in reciprocal transplantations at native altitudinal sites. In this incipient stage of divergence, only a minor proportion of genes appear constitutively differentially expressed between the ecotypes in both pairs, regardless of the growing environment. Both derived, montane populations bear comparatively higher plasticity of gene expression than the alpine populations. Genes that change expression plastically or constitutively underlie similar ecologically relevant pathways, related to response to drought and trichome formation. Other relevant processes, such as photosynthesis, rely mainly on plastic changes. The enhanced plasticity consistently observed in the montane ecotype likely evolved as a response to the newly colonized, drier, and warmer niche. We report a striking parallelism of directional changes in gene expression plasticity. Thus, plasticity appears to be a key mechanism shaping the initial stages of phenotypic evolution, likely fostering adaptation to novel environments., (© 2023 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.)

Functional and structural adjustments of plants in response to environmental factors, including those occurring in alpine habitats, can result in transient acclimation, plastic phenotypic adjustments and/or heritable adaptation. To unravel repeatedly selected traits with potential adaptive advantage, we studied parallel (ecotypic) and non-parallel (regional) differentiation in leaf traits in alpine and foothill ecotypes of Arabidopsis arenosa . Leaves of plants from eight alpine and eight foothill populations, representing three independent alpine colonization events in different mountain ranges, were investigated by microscopy techniques after reciprocal transplantation. Most traits clearly differed between the foothill and the alpine ecotype, with plastic adjustments to the local environment. In alpine populations, leaves were thicker, with altered proportions of palisade and spongy parenchyma, and had fewer trichomes, and chloroplasts contained large starch grains with less stacked grana thylakoids compared to foothill populations. Geographical origin had no impact on most traits except for trichome and stomatal density on abaxial leaf surfaces. The strong parallel, heritable ecotypic differentiation in various leaf traits and the absence of regional effects suggests that most of the observed leaf traits are adaptive. These trait shifts may reflect general trends in the adaptation of leaf anatomy associated with the colonization of alpine habitats.

In the temperate zone of Europe, plants flowering in early spring or at high elevation risk that their reproductive organs are harmed by episodic frosts. Focusing on flowers of two mountain and three early-flowering colline to montane distributed species, vulnerability to ice formation and ice management strategies using infrared video thermography were investigated. Three species had ice susceptible flowers and structural ice barriers, between the vegetative and reproductive organs, that prevent ice entrance from the frozen stems. Structural ice barriers as found in Anemona nemorosa and Muscari sp. have not yet been described for herbaceous species that of Jasminum nudiflorum corroborates findings for woody species. Flowers of Galanthus nivalis and Scilla forbesii were ice tolerant. For all herbs, it became clear that the soil acts as a thermal insulator for frost susceptible below ground organs and as a thermal barrier against the spread of ice between individual flowers and leaves. Both ice barrier types presumably promote that the reproductive organs can remain supercooled, and can at least for a certain time-period escape from effects of ice formation. Both effects of ice barriers appear significant in the habitat of the tested species, where episodic freezing events potentially curtail the reproductive success.

The Eurasian steppes occupy a significant portion of the worldwide land surface and their biota have been affected by specific past range dynamics driven by ice ages-related climatic fluctuations. The dynamic alterations in conditions during the Pleistocene often triggered reticulate evolution and whole genome duplication events. Employing genomic, genetic and cytogenetic tools as well as morphometry we investigate the intricate evolution of Astragalus onobrychis, a widespread Eurasian steppe plant with diploid, tetraploid and octoploid cytotypes. To analyse the heteroploid RADseq dataset we employ both genotype-based and genotype-free methods that result in highly consistent results, and complement our inference with information from the plastid ycf1 region. We uncover a complex and reticulate evolutionary history, including at least one auto-tetraploidization event and two allo-octoploidization events; one of them involved also genetic contributions from other species, most likely A. goktschaicus. The present genetic structure points to the existence of four main clades within A. onobrychis, which only partly correspond to different ploidies. Time-calibrated diffusion models suggest that diversification within A. onobrychis was associated with ice age-related climatic fluctuations during the last million years. We finally argue for the usefulness of uniparentally inherited plastid markers, even in the genomic era, especially when investigating heteroploid systems., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

Evolution is driven by natural selection, favouring individuals adapted in phenotypic traits to the environmental conditions at their growing site. To shed light on ecological and (epi-) genetically based differentiation between Heliosperma pusillum and Heliosperma veselskyi, two reciprocally non-monophyletic, but morphologically and ecologically divergent species from the south-eastern Alps, we studied various leaf anatomical traits and investigated chloroplast ultrastructure in leaves of the two species grown either in their natural habitat or in a common garden. The alpine H. pusillum occurs in open, wet rock habitats, whereas its close relative H. veselskyi is restricted to dry, shady habitats below overhanging rocks in the montane belt. H. pusillum exhibited higher thickness of leaves and palisade layers as adjustments and/or adaptations to higher irradiance and a higher stomatal area index reflecting better water availability. Traits were adjusted plastically, but differed between species grown in a common garden, suggesting that the differentiation between the two species is not solely based on phenotypic plasticity but also has a genetic basis. Our study thus supports the hypothesis that differentiation between the highly interfertile species is likely driven by natural selection.

The xylem hydraulic efficiency and safety is usually measured on mechanically unstressed samples, although trees may be exposed to combined hydraulic and mechanical stress in the field. We analysed changes in hydraulic conductivity and vulnerability to drought-induced embolism during static bending of Picea abies and Pinus sylvestris branches as well as the effect of dynamic bending on the vulnerability. We hypothesized this mechanical stress to substantially impair xylem hydraulics. Intense static bending caused an only small decrease in hydraulic conductance (-19.5 ± 2.4% in P. abies) but no shift in vulnerability thresholds. Dynamic bending caused a 0.4 and 0.8 MPa decrease of the water potential at 50 and 88% loss of conductivity in P. sylvestris, but did not affect vulnerability thresholds in P. abies. With respect to applied extreme bending radii, effects on plant hydraulics were surprisingly small and are thus probably of minor eco-physiological importance. More importantly, results indicate that available xylem hydraulic analyses (of conifers) sufficiently reflect plant hydraulics under field conditions., (© 2014 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.)

Introduction: The treatment of locally advanced cervical carcinoma of uterine cervix is based on concurrent chemoradiotherapy (CCR). The role of laparoscopic lymphadenectomy before CCR and hysterectomy after CCR is not consensual., Patients and Methods: Retrospective multicentric study on 102 patients treated for locally advanced carcinoma of uterine cervix between 1999 and 2008. Disease-free survival and overall survival (OS) were studied., Results: Stages were: stage IB 42%, II 47% and stage III and IVA 11%. All patients received CCR. Eighty-one patients had associated brachytherapy. Sixty-two patients underwent laparoscopic lymphadenectomy before CCR and 31 patients had also para-aortic lymphadenectomy. Eighty-two patients had hysterectomy after CCR. Forty-seven percent (29/62) of patients had a histologically proven pelvic lymph node involvement and 58% (18/31) had a histologically proven para-aortic lymph node involvement. There is no predictor of the presence of residual tumor on hysterectomy. The lymph node involvement before treatment and the presence of residual tumor on hysterectomy were poor prognostic factors on relapse-free survival (SSR) and OS. It has not been shown to benefit from surgery pre- or post-CCR on survival., Conclusion: Surgery can provide major prognosis factor and especially lymphadenectomy before CCR can improve the therapeutic strategy but does not demonstrate significant survival benefit., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

Introduction: The diagnosis of atypical epithelial hyperplasia (AEH) increases with breast cancer screening. AEH is divided in three groups: atypical ductal hyperplasia, columnar cell lesions with atypia, lobular neoplasia. The management of women with AEH is not consensual because of uncertainty about their diagnosis related to the type of the biopsy sampling (core needle biopsy or surgical excision) and their controversial clinical signification between risk marker and true precursor of breast cancer., Material and Methods: A systematic review of published studies was performed. Medline baseline interrogation was performed with the following keywords: atypical ductal hyperplasia, columnar cell lesions with atypia, lobular neoplasia, core needle biopsy, breast cancer, precursor lesion, hormonal replacement therapy. For each breast lesion, identified publications (English or French) were assessed for clinical practise in epidemiology, diagnosis and patient management., Results: With immunohistochemistry and molecular studies, AEH seems to be precursor of breast cancer. But, epidemiological studies show low rate of breast cancer in women with AEH. AEH were still classified as risk factor of breast cancer., Conclusion: Because of high rate of breast cancer underestimation, surgical excision is necessary after the diagnosis of AEH at core needle biopsy. Surgical oncology rules and collaboration with radiologist are required for this surgery. A second operation was not required due to involved margins by AEH (except with pleiomorphic lobular neoplasia) because local control of breast cancer seems to be unchanged. Besides, hormonal replacement therapy for patient with AEH is not recommended because of lack of studies about this subject., (Copyright 2009 Elsevier Masson SAS. All rights reserved.)

The intranuclear filamentous inclusions of a human glioma were analysed with an electron microscope equipped with a goniometer stage. The inclusions consist of 6 to 8 filaments. Considering the organization of the constituent filaments we distinguish three basic types: 1. Filamentous bundles of more or less parallel filaments, forming a cigarshaped inclusion. 2. Crystalloid inclusions: a. Prisms. They consist of stacked layers of strictly parallel filaments. The angle formed by the filaments of adjacent layers if 60 degrees. b. Cylinders. The layers of filaments are bent up and may form either a circle or a spiral, when the inclusion is seen in cross-section. 3. Partially crystalloid or "intermediate" inclusions. We consider them to be transitional forms between types 1 and 2 inclusions. The crystalloid layers of such intermediate inclusions may form either prisms or cylinders. Finally, the similarity between the granulo-fibrillar capsules surrounding granular nuclear bodies and filamentous inclusions, as well as the existence of granular material dispersed between the filaments of some inclusions led us to investigate a relationship between these two structures.

A retrospective review of 39 patients with pyogenic hepatic abscess treated from 1977 through 1984 included 23 patients who were surgically treated and 16 who underwent percutaneous drainage. The average age in each group was similar (about 55 years). The most common cause of abscesses in each group was biliary tract disease. Abscesses caused by portal seeding and local extension were more common in the surgical group, 14 of whom required additional surgical procedures at the time of surgical drainage. Of the 16 patients in the percutaneously drained group, seven were seen during the immediate postoperative period. Most of the abscesses occurred in the right lobe of the liver, but single abscesses in the left lobe (30%) and multiple abscesses (57%) were more common in the surgical group. Klebsiella enterobacter and group D streptococcus were most common in the surgically and percutaneously drained groups, respectively. All patients received antibiotics, with a mean length of treatment of 14 days. Mean time to defervescence was about four days in both groups, with a longer hospital stay for the percutaneously drained group (26 vs 46 days). Morbidity was high in both groups (surgical, 48%; percutaneous, 69%). Three of the percutaneously treated patients required surgical drainage because of highly viscous abscess contents. Mortality was 17% in the surgical group and 13% in the percutaneously drained group. Percutaneous drainage with computed tomography probably should be the initial drainage procedure in patients with pyogenic hepatic abscesses in whom no concomitant surgical procedure is planned. Regardless of treatment, the morbidity and mortality remain high.

Operations, in which a physician removes vital organs of a foetus in order to sustain other organs of the foetus (e. g. the kidneys) in the uterus for an indefinite period and let them work for the gravida, are in accordance with Austrian law if such surgical interventions are carried out within the first three months of pregnancy with the consent of the expectant mother and after previous consultation with a physician; also, if a termination of pregnancy is justified by one of the indications stipulated in Article 97 Paragraph 1 Item 2 of the Austrian Penal Code.