Relationship between lipogenesis and glycogen synthesis in maternal and foetal tissues during late gestation in the rat. Effect of dexamethasone.

We investigated whether the polyenic and allylic phosphate systems of retinyl phosphate are essential for its mannosyl acceptor and donor activities in rat liver postnuclear membranes. Perhydromonoeneretinyl phosphate, a compound without growth-promoting activity in vitamin A-deficient animals, was prepared by catalytic hydrogenation of retinol and phosphorylation. Perhydromonoeneretinyl phosphate mannose synthesis from GDP-mannose showed continued accumulation for at least 60 min, while retinyl phosphate mannose synthesis showed a maximum at 20-30 min and then declined. Moreover, only retinyl phosphate stimulated transfer of mannose from GDP-mannose to endogenous proteins, which were separated by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Thus, hydrogenation of side-chain double bonds in retinyl phosphate impaired only slightly its mannosyl acceptor activity, but caused loss of mannosyl donor activity.     

Orientation of anosmatic pigeons

Summary Test releases performed at five symmetrically arranged sites around the loft, at a distance of 78–99 km from it, showed that 1) anosmatic birds transported without alteration of the earth's magnetic field were completely random-oriented, 2) anosmatic birds transported in a container inside which the intensity of the magnetic field was strongly reduced were unable to orientate homewards and mostly departed according to a preferred compass direction, 3) control birds, which could smell, and were transported without alteration of the magnetic field, were homeward oriented and performed better in homing than both experimental groups. The conclusion is that anosmatic birds are unable to detect home direction at unfamiliar sites and that magnetic stimuli perceived during the outward journey are unable to substitute olfactory cues.Abbreviation PCD preferred compass direction Supported by a grant from the Consiglio Nazionale delle Ricerche     

Temperature dependence of the effects of some monohydric alcohols on the oxygen affinity of hemoglobin: Determination and analysis of thermodynamic parameters

We studied the effects of methanol, ethanol, iso-propanol, and n-propanol on the reaction of hemoglobin with oxygen at various temperatures. The analysis of the results in terms of the Monod-Wyman-Changeux model allowed determination of the overall contribution of the alcohols to the standard enthalpy and entropy differences between the T and R states of hemoglobin. A phenomenological approach allowed us to obtain separately the contributions related to the variations of the bulk dielectric constant of the solvent (bulk electrostatic contributions) and the contributions related to other effects (non-bulk-electrostatic contributions). The values of non-bulk-electrostatic contributions to ΔΔH and ΔΔS supported the suggestion that these contributions are mainly related to protein-solvent hydrophobic interactions.     

An extracellular vesicle epitope profile is associated with acute myocardial infarction

The current standard biomarker for myocardial infarction (MI) is high‐sensitive troponin. Although powerful in clinical setting, search for new markers is warranted as early diagnosis of MI is associated with improved outcomes. Extracellular vesicles (EVs) attracted considerable interest as new blood biomarkers. A training cohort used for diagnostic modelling included 30 patients with STEMI, 38 with stable angina (SA) and 30 matched‐controls. Extracellular vesicle concentration was assessed by nanoparticle tracking analysis. Extracellular vesicle surface‐epitopes were measured by flow cytometry. Diagnostic models were developed using machine learning algorithms and validated on an independent cohort of 80 patients. Serum EV concentration from STEMI patients was increased as compared to controls and SA. EV levels of CD62P, CD42a, CD41b, CD31 and CD40 increased in STEMI, and to a lesser extent in SA patients. An aggregate marker including EV concentration and CD62P/CD42a levels achieved non‐inferiority to troponin, discriminating STEMI from controls (AUC = 0.969). A random forest model based on EV biomarkers discriminated the two groups with 100% accuracy. EV markers and RF model confirmed high diagnostic performance at validation. In conclusion, patients with acute MI or SA exhibit characteristic EV biomarker profiles. EV biomarkers hold great potential as early markers for the management of patients with MI.     

The effectiveness of flower strips and hedgerows on pest control,pollination services and crop yield: a quantitative synthesis

Floral plantings are promoted to foster ecological intensification of agriculture through provisioning of ecosystem services. However, a comprehensive assessment of the effectiveness of different floral plantings, their characteristics and consequences for crop yield is lacking. Here we quantified the impacts of flower strips and hedgerows on pest control (18 studies) and pollination services (17 studies) in adjacent crops in North America, Europe and New Zealand. Flower strips, but not hedgerows, enhanced pest control services in adjacent fields by 16% on average. However, effects on crop pollination and yield were more variable. Our synthesis identifies several important drivers of variability in effectiveness of plantings: pollination services declined exponentially with distance from plantings, and perennial and older flower strips with higher flowering plant diversity enhanced pollination more effectively. These findings provide promising pathways to optimise floral plantings to more effectively contribute to ecosystem service delivery and ecological intensification of agriculture in the future.     

Male flowers in Tulipa pumila Moench (Liliaceae) potentially originate from gender diphasy

We found functionally male individuals in an otherwise hermaphroditic population of Tulipa pumila (Liliaceae) located in Tuscany (central Italy). We investigated the sex ratio of this population, followed by morphometric analyses of the scape, leaves and flowers, and tests on pollen germinability and seed number and mass, in order to infer which sexual strategy produced the observed co-occurrence of male and hermaphrodite individuals. We found that sex ratio deviated from 1:1, and functionally male individuals showed a smaller plant size and a reduced pollen fitness (germinability and siring ability) compared to hermaphrodites. These findings point to a resource-dependent sexual allocation strategy, probably associated with gender diphasy.     

Light controls stamen elongation via cryptochromes,phytochromes and COP1 through HY5 and HYH

In Arabidopsis, stamen elongation, which ensures male fertility, is controlled by the auxin response factor ARF8, which regulates the expression of the auxin repressor IAA19. Here, we uncover a role for light in controlling stamen elongation. By an extensive genetic and molecular analysis we show that the repressor of light signaling COP1, through its targets HY5 and HYH, controls stamen elongation, and that HY5 – oppositely to ARF8 – directly represses the expression of IAA19 in stamens. In addition, we show that in closed flower buds, when light is shielded by sepals and petals, the blue light receptors CRY1/CRY2 repress stamen elongation. Coherently, at flower disclosure and in subsequent stages, stamen elongation is repressed by the red and far‐red light receptors PHYA/PHYB. In conclusion, different light qualities – sequentially perceived by specific photoreceptors – and the downstream COP1–HY5/HYH module finely tune auxin‐induced stamen elongation and thus male fertility.