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排序方式: 共有534条查询结果,搜索用时 93 毫秒
71.
Marcello A. Mannino Giulio Catalano Sahra Talamo Giovanni Mannino Rosaria Di Salvo Vittoria Schimmenti Carles Lalueza-Fox Andrea Messina Daria Petruso David Caramelli Michael P. Richards Luca Sineo 《PloS one》2012,7(11)
Hunter-gatherers living in Europe during the transition from the late Pleistocene to the Holocene intensified food acquisition by broadening the range of resources exploited to include marine taxa. However, little is known on the nature of this dietary change in the Mediterranean Basin. A key area to investigate this issue is the archipelago of the Ègadi Islands, most of which were connected to Sicily until the early Holocene. The site of Grotta d’Oriente, on the present-day island of Favignana, was occupied by hunter-gatherers when Postglacial environmental changes were taking place (14,000-7,500 cal BP). Here we present the results of AMS radiocarbon dating, palaeogenetic and isotopic analyses undertaken on skeletal remains of the humans buried at Grotta d’Oriente. Analyses of the mitochondrial hypervariable first region of individual Oriente B, which belongs to the HV-1 haplogroup, suggest for the first time on genetic grounds that humans living in Sicily during the early Holocene could have originated from groups that migrated from the Italian Peninsula around the Last Glacial Maximum. Carbon and nitrogen isotope analyses show that the Upper Palaeolithic and Mesolithic hunter-gatherers of Favignana consumed almost exclusively protein from terrestrial game and that there was only a slight increase in marine food consumption from the late Pleistocene to the early Holocene. This dietary change was similar in scale to that at sites on mainland Sicily and in the rest of the Mediterranean, suggesting that the hunter-gatherers of Grotta d’Oriente did not modify their subsistence strategies specifically to adapt to the progressive isolation of Favignana. The limited development of technologies for intensively exploiting marine resources was probably a consequence both of Mediterranean oligotrophy and of the small effective population size of these increasingly isolated human groups, which made innovation less likely and prevented transmission of fitness-enhancing adaptations. 相似文献
72.
Claudio Monasterolo Marco Ballestri Giovanna Sotgiu Andrea Guerrini Paolo Dambruoso Katia Sparnacci Michele Laus Michelandrea De Cesare Assunta Pistone Giovanni Luca Beretta Franco Zunino Valentina Benfenati Greta Varchi 《Bioorganic & medicinal chemistry》2012,20(22):6640-6647
We report herein the viability of a novel nanoparticles (NPs) conjugated system, namely the attachment, based on ionic and hydrophobic interactions, of different sulfonated organic salts to positively charged poly(methylmethacrylate) (PMMA)-based core-shell nanoparticles (EA0) having an high density of ammonium groups on their shells. In this context three different applications of the sulfonates@EA0 systems have been described. In detail, their ability as cytotoxic drugs and pro-drugs carriers was evaluated in vitro on NCI-H460 cell line and in vivo against human ovarian carcinoma IGROV-1 cells. Besides, 8-hydroxypyrene-1,3,6-trisulfonic acid, trisodium salt (HPTS) was chosen for NPs loading, and its internalization as bioimaging probe was evaluated on Hep G2 cells. Overall, the available data support the interest for these PMMA NPs@sulfonates systems as a promising formulation for theranostic applications. In vivo biological data strongly support the potential value of these core-shell NPs as delivery system for negatively charged drugs or biologically active molecules. Additionally, we have demonstrated the ability of these PMMA core-shell nanoparticles to act as efficient carriers of fluorophores. In principle, thanks to the high PMMA NPs external charge density, sequential and very easy post-loading of different sulfonates is achievable, thus allowing the preparation of nanocarriers either with bi-modal drug delivery behaviour or as theranostic systems. 相似文献
73.
Cellular SR-BI and ABCA1-mediated cholesterol efflux are gender-specific in healthy subjects 总被引:1,自引:0,他引:1
Catalano G Duchene E Julia Z Le Goff W Bruckert E Chapman MJ Guerin M 《Journal of lipid research》2008,49(3):635-643
We evaluated the impact of gender differences in both the quantitative and qualitative features of HDL subspecies on cellular free cholesterol efflux through the scavenger receptor class B type I (SR-BI), ABCA1, and ABCG1 pathways. For that purpose, healthy subjects (30 men and 26 women) matched for age, body mass index, triglyceride, apolipoprotein A-I, and high density lipoprotein-cholesterol (HDL-C) levels were recruited. We observed a significant increase (+14%; P < 0.03) in the capacity of whole sera from women to mediate cellular free cholesterol efflux via the SR-BI-dependent pathway compared with sera from men. Such enhanced efflux capacity resulted from a significant increase in plasma levels of large cholesteryl ester-rich HDL2 particles (+20%; P < 0.04) as well as from an enhanced capacity (+14%; P < 0.03) of these particles to mediate cellular free cholesterol efflux via SR-BI. By contrast, plasma from men displayed an enhanced free cholesterol efflux capacity (+31%; P < 0.001) via the ABCA1 transporter pathway compared with that from women, which resulted from a 2.4-fold increase in the plasma level of prebeta particles (P < 0.008). Moreover, in women, SR-BI-mediated cellular free cholesterol efflux was significantly correlated with plasma HDL-C (r = 0.72, P < 0.0001), whereas this relationship was not observed in men. In conclusion, HDL-C level may not represent the absolute indicator of the efficiency of the initial step of the reverse cholesterol transport. 相似文献
74.
Lux-Lantos VA Bianchi MS Catalano PN Libertun C 《Cellular and molecular neurobiology》2008,28(6):803-817
Gamma-amino butyric acid (GABA), in addition to being a metabolic intermediate and the main inhibitory neurotransmitter in
the synaptic cleft, is postulated as a neurohormone, a paracrine signaling molecule, and a trophic factor. It acts through
pre- and post-synaptic receptors, named GABAA and GABAC (ionotropic receptors) and GABAB (metabotropic receptor). Here we reviewed the participation of GABAB receptors in the regulation of the hypothalamic-pituitary-gonadal axis, using physiological, biochemical, and pharmacological
approaches in rats, as well as in GABAB1 knock-out mice, that lack functional GABAB receptors. Our general conclusion indicates that GABAB receptors participate in the regulation of pituitary hormone secretion acting both in the central nervous system and directly
on the gland. PRL and gonadotropin axes are affected by GABAB receptor activation, as demonstrated in the rat and also in the GABAB1 knock-out mouse. In addition, hypothalamic and pituitary GABAB receptor expression is modulated by steroid hormones. GABA participation in the brain control of pituitary secretion through
GABAB receptors depends on physiological conditions, being age and sex critical factors.
These results indicate that patients receiving GABAB agonists/antagonists should be monitored for possible endocrine side effects. 相似文献
75.
Monaci P Luzzago A Santini C De Pra A Arcuri M Magistri F Bellini A Ansuini H Ambrosio M Ammendola V Bigotti MG Cirillo A Nuzzo M Nasti AA Neuner P Orsatti L Pezzanera M Sbardellati A Silvestre G Uva P Viti V Barbato G Colloca S Demartis A De Rinaldis E Giampaoli S Lahm A Palombo F Talamo F Vitelli A Nicosia A Cortese R 《PloS one》2008,3(1):e1508
A novel and efficient tagArray technology was developed that allows rapid identification of antibodies which bind to receptors with a specific expression profile, in the absence of biological information. This method is based on the cloning of a specific, short nucleotide sequence (tag) in the phagemid coding for each phage-displayed antibody fragment (phage-Ab) present in a library. In order to set up and validate the method we identified about 10,000 different phage-Abs binding to receptors expressed in their native form on the cell surface (10 k Membranome collection) and tagged each individual phage-Ab. The frequency of each phage-Ab in a given population can at this point be inferred by measuring the frequency of its associated tag sequence through standard DNA hybridization methods. Using tiny amounts of biological samples we identified phage-Abs binding to receptors preferentially expressed on primary tumor cells rather than on cells obtained from matched normal tissues. These antibodies inhibited cell proliferation in vitro and tumor development in vivo, thus representing therapeutic lead candidates. 相似文献
76.
A new complex, [Ru(II)(dcbpyH2)(bdmpp)Cl](PF6) (where bdmpp is 2,6-bis(3,5-dimethyl-N-pyrazoyl)pyridine, dcbpyH2 is 2,2′-bipyridine-4,4′-dicarboxylic acid) is synthesized and characterized by mass spectroscopy, by IR, ES-MS and 1H NMR (1D and 2D) spectroscopies. The broad and very high intensity MLCT absorption band in the visible makes this dye potentially beneficial for the photosensitization process. Cyclic voltammetry analysis displays a well reversible oxidation-reduction wave with E1/2=+0.81 vs. Ag-AgCl. Transparent TiO2 thin film electrodes can easily be chemically modified by the complex and the incorporation of the resulting photoelectrodes in wet regenerative solar cells produced a stable photovoltage of 550 mV and gave a continuous photocurrent of 140 μA cm−2. 相似文献
77.
Kai Zhang Jun He Claudio Catalano Youzhong Guo Jun Liu Chunhao Li 《Molecular microbiology》2020,113(6):1122-1139
The Lyme disease bacterium Borrelia burgdorferi has 7–11 periplasmic flagella (PF) that arise from the cell poles and extend toward the midcell as a flat-ribbon, which is distinct from other bacteria. FlhF, a signal recognition particle (SRP)-like GTPase, has been found to regulate the flagellar number and polarity; however, its role in B. burgdorferi remains unknown. B. burgdorferi has an FlhF homolog (BB0270). Structural and biochemical analyses show that BB0270 has a similar structure and enzymatic activity as its counterparts from other bacteria. Genetics and cryo-electron tomography studies reveal that deletion of BB0270 leads to mutant cells that have less PF (4 ± 2 PF per cell tip) and fail to form a flat-ribbon, indicative of a role of BB0270 in the control of PF number and configuration. Mechanistically, we demonstrate that BB0270 localizes at the cell poles and controls the number and position of PF via regulating the flagellar protein stability and the polar localization of the MS-ring protein FliF. Our study not only provides the detailed characterizations of BB0270 and its profound impacts on flagellar assembly, morphology and motility in B. burgdorferi, but also unveils mechanistic insights into how spirochetes control their unique flagellar patterns. 相似文献
78.
Chamran Hemmati Mehrnoosh Nikooei Assunta Bertaccini 《Journal of Phytopathology》2019,167(10):547-552
A petunia witches’ broom (PvWB) disease, characterized by phyllody, virescence, witches’ broom, little leaf and yellowing, was observed in municipal lands and parks in Bandar Abbas, Hormozgan province, Iran. The disease was present with an average incidence of 20%. PCR and sequencing analysis carried out on selected samples from symptomatic plants showed the presence of a phytoplasma associated with the disease. The molecular comparison of the 16S ribosomal gene indicated 99% sequence identity with the one of “Candidatus Phytoplasma australasia”. This phytoplasma was transmitted to healthy petunia plants under experimental conditions by the leafhopper Orosius albicinctus that was then demonstrated to be a vector of this phytoplasma. 相似文献
79.
M G Catalano L Costantino R Frairia G Boccuzzi N Fortunati 《Hormones et métabolisme》2007,39(4):288-294
Human sex hormone-binding globulin inhibits the effects of estradiol on proliferation and apoptosis of breast cancer cells. We report here the effect of sex hormone-binding globulin on estradiol regulation of gene expression in MCF-7 breast cancer cells using a selected set of genes. Estradiol upregulates genes that are positive regulators of proliferation (e.g., bcl-2, c-fos, c-myc, cyclin D) or/and related to more aggressive form of breast cancer (e.g. BRCA-1, EGF-R) and downregulates two genes (c-jun and ERalpha). Sex hormone-binding globulin modulates only a selected group of estradiol-controlled genes (inhibiting upregulation of bcl-2, c-myc, EGF-R, PR, and downregulation of ERalpha), starting 48 hours after treatment. Our study demonstrates that in breast cancer cells, sex hormone-binding globulin is effective on few selected genes which are involved in cell growth and apoptosis or related to cell estrogen-dependence and that the protein regulation of estradiol effect is selected and specific. Sex hormone-binding globulin action in estrogen breast cancer cells is strongly associated to cell growth and estrogen-sensitivity. 相似文献
80.
Photoinduction of NADP-linked glyceraldehyde-3-phosphate dehydrogenase activity in etiolated pea seedlings was investigated in the presence of various concentrations of four inhibitors of protein synthesis (cycloheximide, actinomycin D, chloramphenicol and puromycin) and one photosynthesis inhibitor (DCMU), and compared with increase in chlorophyll and total protein contents. The enzymatic activity and chlorophyll showed similar responses to the action of the antibiotics, whereas they were not significantly affected by the presence of DCMU. 相似文献