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51.
52.
Zega G Pennati R Fanzago A De Bernardi F 《The International journal of developmental biology》2007,51(4):307-313
Hydroid planulae metamorphose in response to an inducing external stimulus, usually a bacterial cue. There is evidence that neurotransmitters participate in the signal transduction pathway of hydroid metamorphosis. Eudendrium racemosum is a colonial hydroid common in the Mediterranean Sea. It lacks the medusa stage and the planulae develop on female colonies during the fertile season. In this work, serotonin (5-HT) was localized in some planula ectodermal cells. Co-localization of serotonin and beta-tubulin suggested that 5-HT was present in sensory nervous cells and in different ectodermal cells. To investigate the role of neurotransmitters in metamorphosis, E. racemosum planulae were treated with serotonin and dopamine and with agonists and antagonists of the corresponding receptors. Serotonin and a serotonin receptor agonist induced metamorphosis, while a 5-HT receptor antagonist inhibited it. Dopamine and all dopaminergic drugs used did not show any significant effect on the onset of metamorphosis. Results from this work showed that 5-HT could stimulate metamorphosis in E. racemosum planulae in the presence of a natural inducer. A mechanism by which this neurotransmitter could act in this phase is proposed. 相似文献
53.
This study is an analysis of the patterns of variation of the human hand, particularly the metric characters of palm, fingers and distal phalanges. Anthropometric measurements were performed on 146 Sardinian men and women, aged 21 to 31 years. The data were analyzed by inferential statistics (paired Student's t test, analysis of variance), and Principal Components Analysis. The results indicate that size factors are the principal source of variation. A residual adimensional component of variability is related to diversification between the fingers as a whole and the distal phalanges, and between the thumb and the other fingers. Sexual dimorphism is evident. Men present greater dimensions and greater relative length of the thumb with respect to the other fingers than women. 相似文献
54.
Benfatti F Cardillo G Fabbroni S Galzerano P Gentilucci L Juris R Tolomelli A Baiula M Spartà A Spampinato S 《Bioorganic & medicinal chemistry》2007,15(23):7380-7390
Small constrained non-peptidic molecules consisting of a polyfunctionalized rigid core, carrying appendages corresponding to arginine and aspartic acid side chains, have been recently reported to be promising for drug development. In this work, the 5,6-dihydropyridin-2-one was envisaged as a scaffold to turn into potential integrin ligands, introducing a carboxylic acid and a basic appendage. The synthesis and the antiadhesion activity of a small library of peptidomimetics capable to recognize alpha(v)beta(3) and alpha(5)beta(1) integrins has been herein reported. 相似文献
55.
Mycoplasma pneumoniae (Mp) is a frequent cause of Community Acquired Pneumoniae (CAP). The etiological role of Mp is usually suspected using serological assays, but the detection of specific anti-Mp antibodies becomes possible only 1-2 weeks after the primary infection. On the contrary, direct diagnosis using real-time PCR allows an efficient detection of Mp DNA in all the phases of the infection and particularly during early serum negative periods. In this study, we developed a novel Scorpion-probe real-time PCR-based assay. The probe's uni-molecular structure offers thermodynamic advantages owing to its kinetic reaction, providing faster performances compared to a TaqMan-based assay, but maintaining the same sensitivity and specificity. The Scorpion-based assay was employed on 388 clinical samples and compared with conventional qualitative PCR and serological tests. It was found more sensitive because it also allowed the detection of Mp in specimens found negative using classic qualitative PCR, but displaying seropositivity or a later seroconversion. 相似文献
56.
Giorgio M Trinei M Migliaccio E Pelicci PG 《Nature reviews. Molecular cell biology》2007,8(9):722-728
The reactive oxygen species that are generated by mitochondrial respiration, including hydrogen peroxide (H2O2), are potent inducers of oxidative damage and mediators of ageing. It is not clear, however, whether oxidative stress is the result of a genetic programme or the by-product of physiological processes. Recent findings demonstrate that a fraction of mitochondrial H2O2, produced by a specialized enzyme as a signalling molecule in the pathway of apoptosis, induces intracellular oxidative stress and accelerates ageing. We propose that genes that control H2O2 production are selected determinants of lifespan. 相似文献
57.
Encapsulation and exfoliation of inorganic lamellar fillers into polycaprolactone by electrospinning
The present paper reports, for the first time, the successful fabrication of layered double hydroxide (Mg-Al LDH)-reinforced polycaprolactone (PCL) nanofibers by electrospinning. Either the LDH in carbonate form or an LDH organically modified with 12-hydroxydodecanoic acid (LDH-HA) were incorporated into PCL and electrospun using a voltage of 20 KV. The LDH-HA was prepared by an ionic exchange reaction from pristine LDH and encapsulated into PCL from acetone solutions at 15 wt %. The morphological analysis showed pure PCL fibers with an average diameter of 600 +/- 50 nm, and this dimension was maintained in the fibers with LDH, with the inorganic component residing outside the fibers and not exfoliated. At variance, the fibers with the LDH-HA showed a significantly lower average diameter in the range of 350 +/- 50 nm, indicating the improved electrospinnability of PCL. Moreover, the inorganic lamellae were exfoliated, as shown by X-rays and residing inside the nanofibers as demonstrated by energy dispersive X-ray spectroscopy analysis. The structural parameters, such as degradation temperature and crystallinity, were investigated for all the samples and correlated with the electrospinning process. 相似文献
58.
Grapevine Viruses' Detection and Sanitary Selection in Grapevine Germplasm of Calabria (Southern Italy) 下载免费PDF全文
Giovanna Leo Davide Luison Saverio Bruno Grande Giuliana Albanese Francesco Faggioli 《Journal of Phytopathology》2015,163(7-8):690-693
A survey of grapevine viruses present in the region of Calabria (southern Italy) was carried out, and the sanitary selection was conducted on various indigenous varieties. Serological (ELISA) and molecular (multiplex RT‐PCR) tests were used to detect the viruses included in the Italian certification programme: Arabis mosaic virus (ArMV), Grapevine fanleaf virus (GFLV), Grapevine leafroll associated virus 1 (GLRaV‐1), Grapevine leafroll associated virus 2 (GLRaV‐2), Grapevine leafroll associated virus 3 (GLRaV‐3), Grapevine virus A (GVA), Grapevine virus B (GVB) and Grapevine fleck virus (GFkV). The frequency with which the above viruses have been detected was 37.4, 32.6, 12.8, 7.7, 7.3, 1.9 and 0.3%, respectively, for GVA, GLRaV‐3, GFLV, GFKV, GLRaV‐1, GLRaV‐2 and GVB. ArMV was never found. The sanitary selection allowed for the detection of 6 putative clones of ‘Arvino’, 2 of ‘Magliocco dolce’ and 2 of the rootstock ‘17–37’ free of the above‐mentioned viruses. The necessary process for the commercialization of these clones as ‘certified’ propagation material was accomplished, and their official approval by the Italian Ministry of Agriculture is currently in progress. 相似文献
59.
Shafat I Ben-Arush MW Issakov J Meller I Naroditsky I Tortoreto M Cassinelli G Lanzi C Pisano C Ilan N Vlodavsky I Zunino F 《Journal of cellular and molecular medicine》2011,15(9):1857-1864
Heparanase is an endoglycosidase that specifically cleaves heparan sulphate side chains of heparan sulphate proteoglycans, activity that is strongly implicated in cell migration and invasion associated with tumour metastasis, angiogenesis and inflammation. Heparanase up-regulation was documented in an increasing number of human carcinomas, correlating with reduced post-operative survival rate and enhanced tumour angiogenesis. Expression and significance of heparanase in human sarcomas has not been so far reported. Here, we applied the Ewing's sarcoma cell line TC71 and demonstrated a potent inhibition of cell invasion in vitro and tumour xenograft growth in vivo upon treatment with a specific inhibitor of heparanase enzymatic activity (compound SST0001, non-anticoagulant N-acetylated, glycol split heparin). Next, we examined heparanase expression and cellular localization by immunostaining of a cohort of 69 patients diagnosed with Ewing's sarcoma. Heparanase staining was noted in all patients. Notably, heparanase staining intensity correlated with increased tumour size (P = 0.04) and with patients' age (P = 0.03), two prognostic factors associated with a worse outcome. Our study indicates that heparanase expression is induced in Ewing's sarcoma and associates with poor prognosis. Moreover, it encourages the inclusion of heparanase inhibitors (i.e. SST0001) in newly developed therapeutic modalities directed against Ewing's sarcoma and likely other malignancies. 相似文献
60.
Gentile A Toietta G Pazzano V Tsiopoulos VD Giglio AF Crea F Pompilio G Capogrossi MC Di Rocco G 《Molecular biology of the cell》2011,22(5):581-592
Recent studies have underscored a role for the epicardium as a source of multipotent cells. Here, we investigate the myogenic potential of adult human epicardium-derived cells (EPDCs) and analyze their ability to undergo skeletal myogenesis when cultured with differentiating primary myoblasts. Results are compared to those obtained with mesenchymal stromal cells (MSCs) and with endothelial cells, another mesodermal derivative. We demonstrate that EPDCs spontaneously fuse with pre-existing myotubes with an efficiency that is significantly higher than that of other cells. Although at a low frequency, endothelial cells may also contribute to myotube formation. In all cases analyzed, after entering the myotube, nonmuscle nuclei are reprogrammed to express muscle-specific genes. The fusion competence of nonmyogenic cells in vitro parallels their ability to reconstitute dystrophin expression in mdx mice. We additionally show that vascular cell adhesion molecule 1 (VCAM1) expression levels of nonmuscle cells are modulated by soluble factors secreted by skeletal myoblasts and that VCAM1 function is required for fusion to occur. Finally, treatment with interleukin (IL)-4 or IL-13, two cytokines released by differentiating myotubes, increases VCAM1 expression and enhances the rate of fusion of EPDCs and MSCs, but not that of endothelial cells. 相似文献