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21.
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
22.
Donato Chiatante Gabriella S. Scippa Lucia Maiuro Elisabetta Onelli Giuseppe Patrignani 《Plant biosystems》2013,147(1):35-47
ABSTRACT To understand the mechanisms which enable the nucleus to function under low water potential, the morphology and biochemistry of potato cell nuclei were studied. Conformational modifications were observed in the chromatin of nuclei of cells growing under low water potential. These modifications include a higher number of heterochromatic centres, enlargement of the nuclear diameter, and a different accessibility of DNA to the action of restriction enzymes. Biochemical analyses showed that these chromatin modifications may coincide with quantitative and qualitative variations of several nuclear proteins, some of which may belong to the dehydrin family. We especially focussed our attention on a 45-kDa protein that is heat-stable and is recognised by an antibody raised against the conserved domain of dehydrins. The survival of potato cells in an environment where water availability is low may depend on several simultaneous events regarding the nucleus. The accumulation in the nucleus of specific proteins such as dehydrins could be required to stabilise the chromatin by means of their molecule-salvation action. Further studies are in progress to check whether or not variations in chromatin organisation may be one of the numerous traits that a cell must acquire to become water-stress resistant. 相似文献
23.
Nicola Bizzaro Elena Bartoloni Gabriella Morozzi Stefania Manganelli Valeria Riccieri Paola Sabatini Matteo Filippini Marilina Tampoia Antonella Afeltra Giandomenico Sebastiani Claudia Alpini Vittorio Bini Onelia Bistoni Alessia Alunno Roberto Gerli 《Arthritis research & therapy》2013,15(1):R16
Introduction
The diagnostic, predictive and prognostic role of anti-cyclic citrullinated peptide (CCP) antibodies in rheumatoid arthritis (RA) patients is widely accepted. Moreover, detection of these antibodies in subjects presenting with undifferentiated arthritis (UA) is associated with a significant risk to develop the disease. On the other hand, clinical and prognostic significance of evaluating anti-CCP levels in subjects with inflammatory arthritis at disease onset has not been fully clarified. The goal of this prospective study is to analyze the value and prognostic significance of anti-CCP titer quantification in UA subjects.Methods
Serial anti-CCP assays were measured in 192 consecutive patients presenting with UA lasting less than 12 weeks. Clinical and serological data and arthritis outcome were evaluated every 6 months until two years of follow-up.Results
Anti-CCP positivity, at both low and high titer, and arthritis of hand joints significantly predicted RA at two years, risk increasing in subjects with high anti-CCP titers at baseline. Moreover, time to RA diagnosis was shorter in patients with high anti-CCP2 titers at enrollment with respect to those with low antibody concentration.Conclusions
Presence of anti-CCP antibodies, at both low and high concentration, is significantly associated with RA development in subjects with recent onset UA. However, time interval from the onset of the first symptoms to the fulfilment of the classification criteria appears to be directly related to the initial anti-CCP level. 相似文献24.
Anna Viktória Németh Dénes Dudits Márta Molnár-Láng Gabriella Linc 《Journal of applied genetics》2013,54(3):265-269
Salix viminalis L. (2n?=?38) is a diploid dicot species belonging to the Salix genus of the Salicaceae family. This short-rotation woody crop is one of the most important renewable bioenergy resources worldwide. In breeding for high biomass productivity, limited knowledge is available on the molecular cytogenetics of willow, which could be combined with genetic linkage mapping. The present paper describes the adaptation of a fluorescence in situ hybridisation (FISH) protocol as a new approach to analyse the genomic constitution of Salix viminalis using the heterologous DNA clones pSc119.2, pTa71, pTa794, pAs1, Afa-family, pAl1, HT100.3, ZCF1 and the GAA microsatellite marker. Three of the nine probes showed unambiguous signals on the metaphase chromosomes. FISH analysis with the pTa71 probe detected one major 18S-5.8S-26S rDNA locus on the short arm of one chromosome pair; however, the pTa794 rDNA site was not visible. One chromosome pair showed a distinct signal around the centromeric region after FISH with the telomere-specific DNA clone HT100.3. Two chromosome pairs were found to have pAs1 FISH signals, which represent a D-genome-specific insert from Aegilops tauschii. Based on the FISH study, a set of chromosomes with characteristic patterns is presented, which could be used to establish the karyotype of willow species. 相似文献
25.
Paola Luciani Cristiana Deledda Susanna Benvenuti Roberta Squecco Ilaria Cellai Benedetta Fibbi Ilaria Maddalena Marone Corinna Giuliani Giulia Modi Fabio Francini Gabriella Barbara Vannelli Alessandro Peri 《PloS one》2013,8(8)
Exendin-4 is a molecule currently used, in its synthetic form exenatide, for the treatment of type 2 diabetes mellitus. Exendin-4 binds and activates the Glucagon-Like Peptide-1 Receptor (GLP-1R), thus inducing insulin release. More recently, additional biological properties have been associated to molecules that belong to the GLP-1 family. For instance, Peptide YY and Vasoactive Intestinal Peptide have been found to affect cell adhesion and migration and our previous data have shown a considerable actin cytoskeleton rearrangement after exendin-4 treatment. However, no data are currently available on the effects of exendin-4 on tumor cell motility. The aim of this study was to investigate the effects of this molecule on cell adhesion, differentiation and migration in two neuroblastoma cell lines, SH-SY5Y and SK-N-AS. We first demonstrated, by Extra Cellular Matrix cell adhesion arrays, that exendin-4 increased cell adhesion, in particular on a vitronectin substrate. Subsequently, we found that this molecule induced a more differentiated phenotype, as assessed by i) the evaluation of neurite-like protrusions in 3D cell cultures, ii) the analysis of the expression of neuronal markers and iii) electrophysiological studies. Furthermore, we demonstrated that exendin-4 reduced cell migration and counteracted anchorage-independent growth in neuroblastoma cells. Overall, these data indicate for the first time that exendin-4 may have anti-tumoral properties. 相似文献
26.
Erzsébet Fehér Éva Pongor Károly Altdorfer László Kóbori Gabriella Lengyel 《Cell and tissue research》2013,354(2):543-550
Bidirectional interaction between immune and nervous systems is considered an important biological process in health and disease. However, little is known about the mechanisms involved in their interaction in the human liver. This study examines the distribution of intrahepatic NPY, SP immunoreactive (IR) nerve fibers and their antomical relationship with immunocells containing tumor necrosis factor-α (TNF-α) and nuclear factor κB (NF-κB) in patients with autoimmune hepatitis. Liver specimens were obtained from control liver and autoimmune hepatitis patients. The immunoreactivity was determined by immunohisto- and immunocytochemistry and confocal laser microscopy. In hepatitis, the number of NPY-IR and SP-IR nerve fibers increased significantly. These IR nerve fibers were in very close contact with the lymphocytes. In healthy controls, no NPY-IR, SP-IR or NF-κB IR lymphocytes and only a few TNF-α positive cells, were observed. In hepatitis, some of the lymphocytes showed immunoreactivity for SP and NPY in the portal area. Fluorescent double-labeled immunostaining revealed that in these cells NPY did not colocalize with TNF-α or NF-κB. However, some of the SP fluorescence-positive immune cells exhibited immunostaining for p65 of NF-κB, where their labeling was detected in the nuclei. Under the electronmicroscope, these cells could be identified (lymphocytes, plasmacells and mast cells). The gap between the IR nerve fibers and immunocells was 1 μm or even less. Overexpression of SP in lymphocytes may amplify local inflammation, while NPY may contribute to liver homeostasis in hepatitis. Neural immunomodulation (SP antagonists and NPY) might be a novel therapeutic concept in the management of liver inflammation. 相似文献
27.
New records of Cynipid gall wasps and inquilines for the Italian peninsula and Sicily and their new host plants for the Palaearctic Region are listed and commented on. Among them we find: Cerroneuroterus cerrifloralis (Müllner 1901) as new for Italy and new for the Palaearctic region as host on Quercus suber; Andricus multiplicatus Giraud 1859 on Q. suber, as new host for the Palaearctic region; Aylax papaveris (Perris 1839), reported in Italy over a century ago, but later overlooked; Cerroneuroterus minutulus (Giraud 1859), also reported more than a century ago from Sicily, but later overlooked. Among the inquilines are here listed: Synergus variabilis Mayr 1872, emerged from Janetia cerris (Kollar 1850) galls (Diptera Cecidomyiidae), and found for the first time in the Palaearctic Region as host on Q. suber; Saphonecrus haimi (Mayr 1872) and Saphonecrus barbotini Pujade-Villar & Nieves-Aldrey 1986, are new records for Italy. 相似文献
28.
29.
Jose-Luis Reyes Hernandez Gabriella Leung Derek M. McKay 《International journal for parasitology》2013,43(3-4):233-243
Helminth parasites are masters of immune regulation; a likely prerequisite for long-term survival by circumventing their hosts’ attempt to eradicate them. From a translational perspective, knowledge of immune events as a response to infection with a helminth parasite could be used to reduce the intensity of unwanted inflammatory reactions. Substantial data have accumulated showing that inflammatory reactions that promote a variety of auto-inflammatory diseases are dampened as a consequence of infection with helminth parasites, via either the mobilization of an anti-worm spectrum of immune events or by the direct effect of secretory/excretory bioactive immunomodulatory molecules released from the parasite. However, many issues are outstanding in the definition of the mechanism(s) by which infection with helminth parasites can affect the outcome, positively or negatively, of concomitant disease. We focus on a subgroup of this complex group of metazoan parasites, the cestodes, summarizing studies from rodent models that illustrate if, and by what mechanisms, infection with tapeworms ameliorate or exaggerate disease in their host. The ability of infection with cestodes, or other classes of helminth, to worsen a disease course or confer susceptibility to intracellular pathogens should be carefully considered in the context of ‘helminth therapy’. In addition, poorly characterised cestode extracts can regulate murine and human immunocyte function, yet the impact of these in the context of autoimmune or allergic diseases is poorly understood. Thus, studies with cestodes, as representative helminths, have helped cement the concept that infection with parasitic helminths can inhibit concomitant disease; however, issues relating to long-term effects, potential side-effects, mixed pathogen infections and purification of immunomodulatory molecules from the parasite remain as challenges that need to be addressed in order to achieve the use of helminths as anti-inflammatory agents for human diseases. 相似文献
30.
Daniela Valenti Lidia de Bari Gabriella Arcangela Manente Leonardo Rossi Luciano Mutti Laura Moro Rosa Anna Vacca 《生物化学与生物物理学报:疾病的分子基础》2013,1832(12):2085-2096
Increasing evidence reveals a large dependency of epithelial cancer cells on oxidative phosphorylation (OXPHOS) for energy production. In this study we tested the potential of epigallocatechin-3-gallate (EGCG), a natural polyphenol known to target mitochondria, in inducing OXPHOS impairment and cell energy deficit in human epitheliod (REN cells) and biphasic (MSTO-211H cells) malignant pleural mesothelioma (MMe), a rare but highly aggressive tumor with high unmet need for treatment. Due to EGCG instability that causes H2O2 formation in culture medium, the drug was added to MMe cells in the presence of exogenous superoxide dismutase and catalase, already proved to stabilize the EGCG molecule and prevent EGCG-dependent reactive oxygen species formation. We show that under these experimental conditions, EGCG causes the selective arrest of MMe cell growth with respect to normal mesothelial cells and the induction of mitochondria-mediated apoptosis, as revealed by early mitochondrial ultrastructure modification, swelling and cytochrome c release. We disclose a novel mechanism by which EGCG induces apoptosis through the impairment of mitochondrial respiratory chain complexes, particularly of complex I, II and ATP synthase. This induces a strong reduction in ATP production by OXPHOS, that is not adequately counterbalanced by glycolytic shift, resulting in cell energy deficit, cell cycle arrest and apoptosis. The EGCG-dependent negative modulation of mitochondrial energy metabolism, selective for cancer cells, gives an important input for the development of novel pharmacological strategies for MMe. 相似文献