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1.
Feeding rats a hyperlipidic diet in which animals were offered daily a variety of high-energy food resulted in a significant increase of serum free fatty acids and a decrease of phospholipids with respect to controls. On the contrary, there were no significant differences in erythrocyte membrane total lipid composition between the two groups. Erythrocyte membranes showed a significant decrease in saturated fatty acid content and a significant increase in (n-6) polyunsaturated fatty acid content; (n-3) polyunsaturated fatty acids significantly decreased. Membrane fluidity, investigated by fluorescence polarization of diphenylhexatriene, significantly increased in the erythrocyte membranes of the experimental group. These results seem compatible with the decreased saturated/unsaturated fatty acid ratio. A significant decrease of (Na+-K+)ATPase activity occurred in erythrocyte membranes of the experimental group rats with respect to the controls.  相似文献   
2.
Melanoma growth stimulatory activity (MGSA) was originally described as an endogenous growth factor for human melanoma cells. To test the hypothesis that an MGSA autocrine loop is responsible for the partial freedom from growth control observed in nevocytes and melanoma cells, MGSA growth response and MGSA mRNA/protein levels were examined in these cells compared with normal melanocytes. As a single agent, or in combination with other factors, MGSA stimulated the growth of normal human epidermal melanocytes as well as other growth promoters for melanocytes. Nevocytes were not as responsive to exogenous MGSA as melanocytes. MGSA mRNA was minimal or not detected in cultured normal melanocytes, although the protein was present when the cells were cultured in the presence of serum/growth factors and absent when serum/growth factors were omitted. In contrast, MGSA mRNA was constitutively expressed in the absence of exogenous growth factors in cultures established from benign intradermal and dysplastic nevi and melanoma lesions in different stages of tumor progression. Nevus cultures contained immunoreactive MGSA protein in the presence of serum but were negative or only faintly positive in the absence of serum. Melanoma cell lines were positive for MGSA protein in both the presence and the absence of serum. Thus, continued expression of both MGSA mRNA and MGSA protein in the absence of exogenous hormones or serum factors may correlate with partial freedom from growth control exhibited by malignant melanocytes.  相似文献   
3.
This report demonstrates that the expression of melanoma growth stimulatory activity (MGSA) mRNA can be modulated in a positive fashion in the Hs294T human melanoma cell line by PDGF and MGSA. There is close correlation between MGSA expression and the pattern of cell growth in Hs294T cells.  相似文献   
4.
We present a list of Italian freshwater and marine Oligochaeta in the families Lumbriculidae, Haplotaxidae, Tubificidae, Naididae, Propappidae, Criodrilidae, and Lumbricidae, representing 57 genera and 130 species. Published data reflect the incomplete knowledge of the Italian oligochaete fauna, restricted to certain geographical areas. Subterranean aquatic and marine fauna are of particular interest as these have been studied the least. We provide a comprehensive review of the Naididae including, for the first time, southern Italy and the islands of Sicily and Sardinia. The distribution of species is discussed and taxonomic problems arising from the morphological variability of Italian material are examined.  相似文献   
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6.
Vanadium uptake by whole cells and isolated cell walls of the yeast Saccharomyces cerevisiae was studied. When orthovanadate was added to wild-type S. cerevisiae cells growing in rich medium, growth was inhibited as a function of the VO4 3- concentration and the growth was completely arrested at a concentration of 20 mM of VO4 3- in YEPD. Electron paramagnetic resonance (EPR) spectroscopy was used to obtain structural and dynamic information about the cell-associated paramagnetic vanadyl ion. The presence of EPR signals indicated that vanadate was reduced by whole cells to the vanadyl ion. On the contrary, no EPR signals were detected after interaction of vanadate with isolated cell walls. A mobile and an immobile species associated in cells with small chelates and with macromolecular sites, respectively, were identified. The value of rotational correlation time r indicated the relative motional freedom at the macromolecular site. A strongly immobilized vanadyl species bound to polar sites mainly through coulombic attractions was detected after interaction of VO2+ ions with isolated cell walls.  相似文献   
7.
This work reviews nearly 90 years of ape keeping and housing at the Giardino Zoologico in Rome, and offers an overview of the scientific research carried out on these primates. It may thus contribute to a better historical knowledge of primate zoo management in Italy. Furthermore, particular attention is paid to morphological aspects in orangutan physical development that should deserve further research.  相似文献   
8.
Data on immune responses during human Ebola virus disease (EVD) are scanty, due to limitations imposed by biosafety requirements and logistics. A sustained activation of T-cells was recently described but functional studies during the acute phase of human EVD are still missing. Aim of this work was to evaluate the kinetics and functionality of T-cell subsets, as well as the expression of activation, autophagy, apoptosis and exhaustion markers during the acute phase of EVD until recovery. Two EVD patients admitted to the Italian National Institute for Infectious Diseases, Lazzaro Spallanzani, were sampled sequentially from soon after symptom onset until recovery and analyzed by flow cytometry and ELISpot assay. An early and sustained decrease of CD4 T-cells was seen in both patients, with an inversion of the CD4/CD8 ratio that was reverted during the recovery period. In parallel with the CD4 T-cell depletion, a massive T-cell activation occurred and was associated with autophagic/apoptotic phenotype, enhanced expression of the exhaustion marker PD-1 and impaired IFN-gamma production. The immunological impairment was accompanied by EBV reactivation. The association of an early and sustained dysfunctional T-cell activation in parallel to an overall CD4 T-cell decline may represent a previously unknown critical point of Ebola virus (EBOV)-induced immune subversion. The recent observation of late occurrence of EBOV-associated neurological disease highlights the importance to monitor the immuno-competence recovery at discharge as a tool to evaluate the risk of late sequelae associated with resumption of EBOV replication. Further studies are required to define the molecular mechanisms of EVD-driven activation/exhaustion and depletion of T-cells.Ebola virus (EBOV) is one of the most deadly human pathogens, causing a severe hemorrhagic fever syndrome in both humans and non-human primates with fatality rates ranging from 50 to 70%.1 The recent outbreak of Ebola Virus Diseases (EVD) in West Africa highlights the pathogenic nature of this virus, the high mortality rates and pandemic potential. To date, there have been over 27 700 cases and >11 280 deaths.1, 2 Although EVD is usually an acute illness, increasing evidences exist of persistent infections and post infection syndromes,3, 4, 5, 6 highlighting the need to identify immune correlates of a protective immune response.Defining human immune responses to EBOV infection, pathogenesis and correlates of protection are important for designing effective therapeutic and vaccination interventions. A decrease in lymphocytes has been observed in studies in mice,7 non-human primates8 and humans,9 and is attributed to apoptotic mechanisms.7, 10 Persistent B and T-cell activation has been described in four survivors as long as one month after discharge from the hospital, suggesting recurrent antigenic stimulation.11 While aberrant immune responses have been described after EBOV infection (reviewed in12, 13), and different patterns of inflammatory mediators have been associated with different clinical outcomes,9, 10, 11, 14, 15, 16, 17 data on human immune responses to Ebola virus remain scanty, due to difficulties in obtaining sequential samples through the course of illness and to limitations imposed by biosafety requirements for laboratory analyses.We conducted a longitudinal study aimed to characterize the kinetics of T-cell phenotypes, activation/differentiation profile, autophagic/apoptotic markers and functionality in two EVD patients from soon after symptom onset through their hospitalization until recovery.  相似文献   
9.
In the mammalian adipose organ cold exposure not only activates typical brown adipose tissue, but also induces browning, that is the formation of thermogenic multilocular adipocytes in white, or predominantly white, adipose depots such as subcutaneous fat. Unlike typical brown adipocytes, newly formed thermogenic adipocytes have been reported not to express the gene zinc finger of the cerebellum 1 (Zic1). Here, a time course approach enabled us to document a significant increase in Zic1 messenger RNA in inguinal subcutaneous fat from acutely (24 hr) cold-exposed mice, which was paralleled by an increase in multilocular and paucilocular uncoupling protein 1-positive adipocytes and in parenchymal noradrenergic innervation. This transient, depot-specific molecular signature was associated not to Zic1 promoter demethylation, but to chromatin remodeling through an H3K9me3 histone modification. These findings challenge the notion that Zic1 is exclusively expressed by typical brown adipocytes and suggest its involvement in brown adipocyte precursor differentiation and/or white-to-brown adipocyte transdifferentiation.  相似文献   
10.
Enzyme-mediated reactions are a useful tool in mutation detection when using a microarray format. Discriminating probes attached to the surface of a DNA chip have to be accessible to target DNA and to the enzyme (ligase or polymerase) that catalyses the formation of a new phosphodiester bond. This requires an appropriate chemical platform. Recently, an oligonucleotide hairpin architecture incorporating multiple phosphorothioate moieties along the loop has been proposed as an effective approach to solid-phase minisequencing. We have explored in depth several variables (stem length, number of phosphorothioates, stem-loop architecture versus linear structure) involved in this strategy by using a solid-phase ligation reaction. Microarrays were fabricated either from aminosilyl-modified glass or from aminated polymeric surfaces made of poly-lysine. Both platforms were bromoacetylated and reacted with thiophosphorylated oligonucleotides. The resulting microarrays were tested using either a synthetic template or a PCR-amplified 16S rRNA genomic region as the target sequence. Our results confirm the robustness of the proposed chemistry. We extend its range of application to solid-phase ligation, demonstrating the effectiveness of multiple anchors and suggest that linear oligonucleotides incorporating multiple phosphorothioates are equivalent to their hairpin-structured counterparts.  相似文献   
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