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881.
The S phase checkpoint pathway preserves genome stability by protecting defective DNA replication forks, but the underlying mechanisms are still understood poorly. Previous work with budding yeast suggested that the checkpoint kinases Mec1 and Rad53 might prevent collapse of the replisome when nucleotide concentrations are limiting, thereby allowing the subsequent resumption of DNA synthesis. Here we describe a direct analysis of replisome stability in budding yeast cells lacking checkpoint kinases, together with a high-resolution view of replisome progression across the genome. Surprisingly, we find that the replisome is stably associated with DNA replication forks following replication stress in the absence of Mec1 or Rad53. A component of the replicative DNA helicase is phosphorylated within the replisome in a Mec1-dependent manner upon replication stress, and our data indicate that checkpoint kinases control replisome function rather than stability, as part of a multifaceted response that allows cells to survive defects in chromosome replication. 相似文献
882.
Epithelial V-like Antigen (EVA), a Novel Member of the Immunoglobulin Superfamily, Expressed in Embryonic Epithelia with a Potential Role as Homotypic Adhesion Molecule in Thymus Histogenesis 总被引:3,自引:0,他引:3 下载免费PDF全文
Maria Guttinger Francesca Sutti Maddalena Panigada Simona Porcellini Barbara Merati Margherita Mariani Tambet Teesalu G. Giacomo Consalez Fabio Grassi 《The Journal of cell biology》1998,141(4):1061-1071
Thymus development depends on a complex series of interactions between thymocytes and the stromal component of the organ. To identify regulated genes during this codependent developmental relationship, we have applied an RNA fingerprinting technique to the analysis of thymus expansion and maturation induced in recombinase-deficient mice injected with anti-CD3 antibodies. This approach led us to the identification of a gene encoding a new member of the immunoglobulin superfamily, named epithelial V-like antigen (EVA), which is expressed in thymus epithelium and strongly downregulated by thymocyte developmental progression. This gene is expressed in the thymus and in several epithelial structures early in embryogenesis. EVA is highly homologous to the myelin protein zero and, in thymus-derived epithelial cell lines, is poorly soluble in nonionic detergents, strongly suggesting an association to the cytoskeleton. Its capacity to mediate cell adhesion through a homophilic interaction and its selective regulation by T cell maturation might imply the participation of EVA in the earliest phases of thymus organogenesis. 相似文献
883.
Lorenzo Ottonetti Lorenzo Tucci Guido Chelazzi Giacomo Santini 《Agricultural and Forest Entomology》2008,10(1):29-36
1 Stable isotopes signatures (δ13C and δ15N) of the most important tree‐dwelling ants in an olive orchard were examined, together with the signatures of the most common herbivores, predators and sap‐sucking insects. The olive orchard consists of separate subunits (trees) surrounded by a matrix of grasses or bare ground, and the role of ants in such a system is not fully understood. 2 None of the selected ant species was exclusive to the olive trees because they were also observed foraging on vegetation (mainly thistle) under the tree crowns. Hence, the relative contributions of these two sources of energy (olive trees versus herbs/grasses) were assessed by comparing the δ13C of ants with the signatures of plants and those of other arthropods collected on the trees and on nearby thistles. Next, the trophic level occupied by the ants and their ecological role within the olive food web were determined by examining the δ15N values and their relationship with indices of ecological performance measuring the potential pressure exerted by each species on the ecosystem. 3 The analysis of 13C signatures revealed a different contribution of the two energy sources, olive trees versus herbs and grasses, with the former being more important for ants. The analysis of 15N signatures suggested separate roles for different ant species: some (Crematogaster scutellaris, Lasius lasioides) occupied a higher trophic level, mostly involved in predation, whereas others (Camponotus piceus, Camponotus lateralis) occupied a lower level, probably involved more in homopteran tending. A fifth species (Camponotus aethiops) was in an intermediate position. Finally, the δ15N levels of the species were significantly correlated with indices of ecological performance. 相似文献
884.
Amedeo Amedei Elena Niccolai Chiara Della Bella Fabio Cianchi Giacomo Trallori Marisa Benagiano Lapo Bencini Marco Bernini Marco Farsi Renato Moretti Gianfranco Del Prete Mario Milco D’Elios 《Cancer immunology, immunotherapy : CII》2009,58(11):1819-1830
Gastric cancer is a significant cause of morbidity and mortality worldwide. Surgical resection remains the primary curative
treatment for gastric adenocarcinoma, but the poor (15–35%) survival rate at 5 years has prompted many studies for new therapeutic
strategies, such as specific immunotherapy. The aim of this study was to analyze the functional properties of the T cell response
to different antigen peptides related to gastric cancer in patients with gastric adenocarcinoma. To this purpose, we have
cloned and characterized tumor-infiltrating T cells (TILs) isolated from the neoplastic gastric tissue samples. A T cell response
specific to different peptides of gastric cancer antigens tested was documented in 17 out of 20 patients, selected for their
HLA-A02 and/or -A24 alleles. Most of the cancer peptide-specific TILs expressed a Th1/Tc1 profile and cytotoxic activity against
target cells. The effector functions of cancer peptide-specific T cells obtained from the peripheral blood of the same patients
were also studied. The majority of peripheral blood peptide-specific T cells also expressed the Th1/Tc1 functional profile.
In conclusion, in most of the patients with gastric adenocarcinoma, a specific type-1 T cell response to gastric cancer antigens
was detectable and would have the potential of hamper tumor cell growth. However, in order to get tumor cell killing in vivo,
the activity and the number of cancer peptide-specific Th1/Tc1 cells probably need to be enhanced by vaccination with the
appropriate cancer antigenic peptides or by injection of the autologus tumor peptide-specific T cells expanded in vitro. 相似文献
885.
Simona Fontana Odessa Schillaci Monica Frinchi Marco Giallombardo Giuseppe Morici Valentina?Di Liberto Riccardo Alessandro Giacomo De Leo Vincenzo Perciavalle Natale Belluardo Giuseppa Mudò 《Bioscience reports》2015,35(3)
In our recent study was shown a significant recovery of damaged skeletal muscle of mice with X-linked muscular dystrophy (mdx) following low-intensity endurance exercise, probably by reducing the degeneration of dystrophic muscle. Consequently, in the present work, we aimed to identify proteins involved in the observed reduction in degenerating fibres. To this end, we used proteomic analysis to evaluate changes in the protein profile of quadriceps dystrophic muscles of exercised compared with sedentary mdx mice. Four protein spots were found to be significantly changed and were identified as three isoforms of carbonic anhydrase 3 (CA3) and superoxide dismutase [Cu-Zn] (SODC). Protein levels of CA3 isoforms were significantly up-regulated in quadriceps of sedentary mdx mice and were completely restored to wild–type (WT) mice values, both sedentary and exercised, in quadriceps of exercised mdx mice. Protein levels of SODC were down-regulated in quadriceps of sedentary mdx mice and were significantly restored to WT mice values, both sedentary and exercised, in quadriceps of exercised mdx mice. Western blot data were in agreement with those obtained using proteomic analysis and revealed the presence of one more CA3 isoform that was significantly changed. Based on data found in the present study, it seems that low-intensity endurance exercise may in part contribute to reduce cell degeneration process in mdx muscles, by counteracting oxidative stress. 相似文献
886.
887.
Periklis Kleitou Ioannis Giovos Francesco Tiralongo Nikolaos Doumpas Giacomo Bernardi 《Zeitschrift fur angewandte Ichthyologie》2019,35(2):576-579
On 5th November 2017, a puffer fish specimen was caught in the Aegean Sea. Morphological and molecular analysis identified it as Lagocephalus guentheri. This first record from Greek waters represents the westernmost observation of the species in the Mediterranean Sea. The expansion and establishment of puffer fish species in the basin are discussed, with particular emphasis on the importance of the additional use of molecular analysis for increasing the efficiency in understanding species spread and dynamics. 相似文献
888.
Roberto Bovara Giacomo Carrea Gianluca Ottolina Sergio Riva 《Biotechnology letters》1993,15(9):937-942
Summary The Vmax and KM of various forms of lipase from Pseudomonas cepacia (powder, adsorbed onto Celite or covalently linked to polyethylene glycol) were determined in organic solvents preequilibrated to water activities (a
w) from <0.1 to 0.84. The model reaction was the transesterification between n-octanol and vinyl butyrate. It was found that KM for the nucleophile increased with increasing a
w for all three lipase forms. Vmax increased with increasing a
w for polyethylene glycol-lipase, whereas there was an optimum at intermediate a
w values (0.11 – 0.38) for lipase powder and Celite-immobilized lipase. 相似文献
889.
Brun P Mastrotto C Beggiao E Stefani A Barzon L Sturniolo GC Palù G Castagliuolo I 《American journal of physiology. Gastrointestinal and liver physiology》2005,288(4):G621-G629
Because neurotensin (NT) and its high-affinity receptor (NTR1) modulate immune responses, chloride secretion, and epithelial cell proliferation, we sought to investigate their role in the repair process that follows the development of mucosal injuries during a persistent inflammation. Colonic NT and NTR1, mRNA, and protein significantly increased only after dextran sodium sulfate (DSS)-induced inflammatory damage developed. Colitis-induced body weight loss, colonic myeloperoxidase activity, and histological damage were significantly enhanced by SR-48642 administration, a nonpeptide NTR1 antagonist, whereas continuous NT infusion ameliorated colitis outcome. To evaluate the NT and NTR1 role in tissue healing, mucosal inflammatory injury was established administering 3% DSS for 5 days. After DSS discontinuation, mice rapidly gained weight, ulcers were healed, and colonic NT, NTR1, and cyclooxygenase (COX)-2 mRNA levels were upregulated, whereas SR-48642 treatment caused a further body weight loss, ulcer enlargement, and a blunted colonic COX-2 mRNA upregulation. In a wound-healing model in vitro, NT-induced cell migration in the denuded area was inhibited by indomethacin but not by an antitransforming growth factor-beta neutralizing antibody. Furthermore, NT significantly increased COX-2 mRNA levels by 2.4-fold and stimulated PGE(2) release in HT-29 cells. These findings suggest that NT and NTR1 are part of the network activated after mucosal injuries and that NT stimulates epithelial restitution at least, in part, through a COX-2 dependent pathway. 相似文献
890.