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Abstract The genus Allium L. in Italy. IV. A DNA cytophotometric study on the pollen grain of Allium chamaemoly L. — A cytophotometric analysis of DNA contents in pollen generative and vegetative nuclei of Allium chamaemoly L. was carried out. DNA synthesis in both nuclei was confirmed and a lightly higher DNA amount than 2C in the vegetative nucleus was pointed out. An analysis of the Fast-green stainable histones in the generative and vegetative nuclei was also accomplished. While the generative nucleus had a very high content of Fast-green stainable histone, the vegetative one have nearly no stainable histone. The occurrence of DNA synthesis and the very low histone content suggest the vegetative nucleus is functional and biochemically activ. The higher than 2C DNA content supports the possibility of a DNA amplification process including probably the amplification of ribosomal cistrons in the pollen vegetative nucleus. 相似文献
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Widely used for mapping afferent activated brain areas in vivo, the label-free intrinsic optical signal (IOS) is mainly ascribed to blood volume changes subsequent to glial glutamate uptake. By contrast, IOS imaged in vitro is generally attributed to neuronal and glial cell swelling, however the relative contribution of different cell types and molecular players remained largely unknown. We characterized IOS to Schaffer collateral stimulation in the rat hippocampal slice using a 464-element photodiode-array device that enables IOS monitoring at 0.6 ms time-resolution in combination with simultaneous field potential recordings. We used brief half-maximal stimuli by applying a medium intensity 50 Volt-stimulus train within 50 ms (20 Hz). IOS was primarily observed in the str. pyramidale and proximal region of the str. radiatum of the hippocampus. It was eliminated by tetrodotoxin blockade of voltage-gated Na+ channels and was significantly enhanced by suppressing inhibitory signaling with gamma-aminobutyric acid(A) receptor antagonist picrotoxin. We found that IOS was predominantly initiated by postsynaptic Glu receptor activation and progressed by the activation of astroglial Glu transporters and Mg2+-independent astroglial N-methyl-D-aspartate receptors. Under control conditions, role for neuronal K+/Cl− cotransporter KCC2, but not for glial Na+/K+/Cl− cotransporter NKCC1 was observed. Slight enhancement and inhibition of IOS through non-specific Cl− and volume-regulated anion channels, respectively, were also depicted. High-frequency IOS imaging, evoked by brief afferent stimulation in brain slices provide a new paradigm for studying mechanisms underlying IOS genesis. Major players disclosed this way imply that spatiotemporal IOS reflects glutamatergic neuronal activation and astroglial response, as observed within the hippocampus. Our model may help to better interpret in vivo IOS and support diagnosis in the future. 相似文献
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Rosa Angela Raccuglia Gabriella Bellone Kristina Loziene Franco Piozzi Sergio Rosselli Antonella Maggio Maurizio Bruno Monique S.J. Simmonds 《Phytochemistry》2010,71(17-18):2087-2091
From the aerial parts of Scutellaria hastifolia, family Lamiaceae (Labiatae), seven neo-clerodane diterpenoids (hastifolins A–G) were isolated. The products are similar to the known scuteparvin and are characterized by being trans-cinnamoyl derivatives. Structures and stereochemistry were determined by intensive NMR investigation. Six of the products form three pairs of epimers at C-13. Hastifolins A–C showed significant antifeedant activity. 相似文献
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Giovanni Corso Joana Figueiredo Simone Pietro De Angelis Federica Corso Antonia Girardi Joana Pereira Raquel Seruca Bernardo Bonanni Patricia Carneiro Gabriella Pravettoni Elena Guerini Rocco Paolo Veronesi Giacomo Montagna Virgilio Sacchini Sara Gandini 《Journal of cellular and molecular medicine》2020,24(11):5930-5936
E-cadherin protein (CDH1 gene) integrity is fundamental to the process of epithelial polarization and differentiation. Deregulation of the E-cadherin function plays a crucial role in breast cancer metastases, with worse prognosis and shorter overall survival. In this narrative review, we describe the inactivating mechanisms underlying CDH1 gene activity and its possible translation to clinical practice as a prognostic biomarker and as a potential targeted therapy. 相似文献
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Gabriella Galatà Andrés C. García-Montero Thomas Kristensen Ahmed A.Z. Dawoud Javier I. Muñoz-González Manja Meggendorfer Paola Guglielmelli Yvette Hoade Ivan Alvarez-Twose Christian Gieger Konstantin Strauch Luigi Ferrucci Toshiko Tanaka Stefania Bandinelli Theresia M. Schnurr Torsten Haferlach Sigurd Broesby-Olsen Hanne Vestergaard William J. Tapper 《American journal of human genetics》2021,108(2):284-294