A biometric study of some hybridizing Crataegus populations in Denmark

Crataegus curvisepala Lindm., C. laevigata (Poiret) DC. and C. monogyna Jacq. (Rosaceae) form hybrid complexes in Denmark due to introgression. C. palmstruchii Lindm. seems to be variously introgressed individuals of C. laevigata. C. eremitagensis Raunk., C. raavadensis Raunk. and C. schumacheri Raunk. apparently belong to C. curvisepala x laevigata. The delimitation between C. curvisepala x laevigata and C. laevigata x monogyna is discussed.     

Apport de la TEMP/TDM pour la détection du ganglion sentinelle dans les cancers du col utérin et de l’endomètre

The sentinel lymph node procedure is still under evaluation for the management of cervical and endometrial carcinomas. The aim of our study was to determine the diagnostic accuracy of single-photon emission computed tomography/computed tomography (SPECT/CT) for preoperative sentinel lymph node mapping in uterine cancers. Sixty-eight patients with cervical (n = 42) or endometrial carcinoma (n = 26) underwent preoperative lymphoscintigraphy for sentinel node mapping. Sentinel node detection rate with conventional planar imaging was similar to that of SPECT/CT (87.1 versus 91.8 %) in the whole cohort. However, SPECT/CT detected a higher number of sentinel nodes in more than one third of patients, affected by either cervical or endometrial carcinoma. The rate of non or insufficiently contributive procedures (lack of uptake or unilateral uptake) in endometrial carcinomas was 47 % with conventional planar imaging, and 30 % with SPECT/CT. Sensitivity of both procedures for the detection of metastatic nodes was 81.8 %, compared to 100 % for the intraoperative combined detection (gamma probe sonde and blue dye). The impact of SPECT/CT for the sentinel lymph node detection in cervical and endometrial carcinomas needs further evaluation. Nevertheless, SPECT/CT may provide additional information when conventional planar imaging detects only unilateral uptake, may improve identification of atypical localizations, and facilitate surgical approach.     

Different iron sources to study the physiology and biochemistry of iron metabolism in marine micro-algae

We compared ferric EDTA, ferric citrate and ferrous ascorbate as iron sources to study iron metabolism in Ostreococcus tauri, Phaeodactlylum tricornutum and Emiliania huxleyi. Ferric EDTA was a better iron source than ferric citrate for growth and chlorophyll levels. Direct and indirect experiments showed that iron was much more available to the cells when provided as ferric citrate as compared to ferric EDTA. As a consequence, growth media with iron concentration in the range 1–100 nM were rapidly iron-depleted when ferric citrate—but not ferric EDTA was the iron source. When cultured together, P. tricornutum cells overgrew the two other species in iron-sufficient conditions, but E. huxleyi was able to compete other species in iron-deficient conditions, and when iron was provided as ferric citrate instead of ferric EDTA, which points out the critical influence of the chemical form of iron on the blooms of some phytoplankton species. The use of ferric citrate and ferrous ascorbate allowed us to unravel a kind of regulation of iron uptake that was dependent on the day/night cycles and to evidence independent uptake systems for ferrous and ferric iron, which can be regulated independently and be copper-dependent or independent. The same iron sources also allowed one to identify molecular components involved in iron uptake and storage in marine micro-algae. Characterizing the mechanisms of iron metabolism in the phytoplankton constitutes a big challenge; we show here that the use of iron sources more readily available to the cells than ferric EDTA is critical for this task.     

Does urbanization affect selective pressures and life‐history strategies in the common blackbird (Turdus merula L.)?

Urbanization, one of the most extreme land‐use alterations, is currently spreading, and the number of species confronting these changes is increasing. However, contradictory results of previous studies impede a clear interpretation of which selective pressure (nest predation or food limitation) is more important in urban habitats compared with natural situations, and whether birds can confront them by adjusting their life‐history strategies. We investigated life‐history syndromes of three common blackbird (Turdus merula) populations differing in their human influence (urban, rural, and woodland). We analysed daily nest predation and nestling starvation rates to assess the relative importance of these selection pressures in each habitat. Simultaneously, several life‐history traits were investigated to determine if T. merula seem adapted to their main source of selection. Food limitation was more important in the city, whereas nest predation was the most important selective force in the forest. The rural habitat was characterized by an intermediate influence of these two factors. Life‐history syndromes, as the covariation of a suite of traits, confirmed these results because T. merula seem well adapted to the main cause of selection in each habitat. Our results are consistent with urbanization imposing new challenges on birds, and that they adaptively respond to them. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 759–766.     

On the history of nuclear matrix manifestation

The nonchromatin proteinous residue of the cell nucleus was revealed in our laboratory as early as in 1948 and then identified by light and electron microscopy as residual nucleoli,intranuclear network and nuclear envelope before 1960,This structure termed afterwards as “nuclear residue“,“nuclear skeleton“,“nuclear cage“,“nuclear carcass“etc.,was much later(in 1974) isolated,studied and entitled as “nuclear matrix“ by Berezney and Coffey,to whom the discovery of this residual structure is often wronly ascribed.The real history of nuclear matrix manifestation is reported in this paper.     

PET-MRI in oncology

Hybrid positron emission tomography (PET)-MRI imaging enable the acquisition of functional information by PET, and structural as well as functional information by MRI. The two modalities are complementary: PET offers unparalleled sensitivity to molecular events, e.g. occupation of receptors, activity of glucose metabolism, during tumor or inflammation; while MRI offers high soft tissue contrast (including in highly mobile structures such as the heart) and other information (diffusion, blood flow, spectroscopy). Simultaneous acquisition is crucial for understanding brain function, the pathophysiology of cancer, mechanic cardiovascular dysfunction, and disorders of nutrition and metabolism.