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71.
Carlo Garzelli Agostino Bazzichi Addawe Mohamed Dayah Maria Manunta Marina Incaprera Giuseppe Falcone 《FEMS microbiology letters》1992,100(1-3):449-454
A human Epstein-Barr virus (EBV)-positive lymphoblastoid B cell line, named BA-D10-4, produces a factor of a molecular mass less than 10 kDa that promotes cell proliferation of both BA-D10-4 cells and other human T or B lymphoid cell lines, either EBV-positive or -negative. The factor synergizes with higher molecular mass autocrine growth factors and makes both BA-D10-4 cells and B cell lines from Burkitt's lymphoma, but not cells from T cell leukemia, more responsive to interleukin-1 and interleukin-6. Therefore, this low molecular mass factor seems to be an autocrine growth factor per se and to have the characteristics of a competence factor. 相似文献
72.
Melinda L. Micallef Paul M. D’Agostino Deepti Sharma Rajesh Viswanathan Michelle C. Moffitt 《BMC genomics》2015,16(1)
Background
Cyanobacteria are well known for the production of a range of secondary metabolites. Whilst recent genome sequencing projects has led to an increase in the number of publically available cyanobacterial genomes, the secondary metabolite potential of many of these organisms remains elusive. Our study focused on the 11 publically available Subsection V cyanobacterial genomes, together with the draft genomes of Westiella intricata UH strain HT-29-1 and Hapalosiphon welwitschii UH strain IC-52-3, for their genetic potential to produce secondary metabolites. The Subsection V cyanobacterial genomes analysed in this study are reported to produce a diverse range of natural products, including the hapalindole-family of compounds, microcystin, hapalosin, mycosporine-like amino acids and hydrocarbons.Results
A putative gene cluster for the cyclic depsipeptide hapalosin, known to reverse P-glycoprotein multiple drug resistance, was identified within three Subsection V cyanobacterial genomes, including the producing cyanobacterium H. welwitschii UH strain IC-52-3. A number of orphan NRPS/PKS gene clusters and ribosomally-synthesised and post translationally-modified peptide gene clusters (including cyanobactin, microviridin and bacteriocin gene clusters) were identified. Furthermore, gene clusters encoding the biosynthesis of mycosporine-like amino acids, scytonemin, hydrocarbons and terpenes were also identified and compared.Conclusions
Genome mining has revealed the diversity, abundance and complex nature of the secondary metabolite potential of the Subsection V cyanobacteria. This bioinformatic study has identified novel biosynthetic enzymes which have not been associated with gene clusters of known classes of natural products, suggesting that these cyanobacteria potentially produce structurally novel secondary metabolites.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1855-z) contains supplementary material, which is available to authorized users. 相似文献73.
Tiziana Comito Elena Clerici Angelo Tozzi Giuseppe D’Agostino 《Reports of Practical Oncology and Radiotherapy》2015,20(6):464-471
BackgroundThe outstanding innovations made by early diagnosis, novel surgical techniques, effective chemotherapy regimens and conformal radiotherapy, have significantly improved patients overall survival and quality of life. Multidisciplinary approach to cancer has also led to an increased prevalence of patients with few, organ-confined metastases, who can experience long-term survival even if their disease is no longer localized. Liver is one of the most common site for metastatic disease from several cancers, and when metastatic disease is confined to liver, given the ability of this organ to regenerate almost to its optimal volume, surgical resection represents the standard of care because is associated with a better prognosis. Approximately 70–90% of liver metastases, however, are unresectable and a safe, effective alternative therapeutic option is necessary for these patients.Materials and methodsA review of the current literature was performed to analyze the role of SBRT in treating liver metastases from different cancers. A literature search using the terms “SBRT” and “liver metastases” was carried out in PUBMED.ResultsStereotactic body radiation therapy has shown to provide promising results in the treatment of liver metastases, thanks to the ability of this procedure to deliver a conformal high dose of radiation to the target lesion and a minimal dose to surrounding critical tissues.ConclusionStereotactic body radiation therapy is a non-invasive, well-tolerated and effective treatment for patients with liver metastases not suitable for surgical resection. 相似文献
74.
Sergio Giuffrida Rosario Troia Chiara Schiraldi Antonella D??Agostino Mario De Rosa Lorenzo Cordone 《Food biophysics》2011,6(2):217-226
Saccharide-based biopreservation is widely studied because of its scientific importance and possible technological outcomes
for food and pharmaceutical industries. Ternary protein/saccharide/water systems have been extensively exploited to model
the characteristics of the in vivo biopreservation process. A tight, water dependent, protein–matrix coupling has been shown
to occur in various simple saccharide amorphous matrices, which is stronger in trehalose. The efficiency as bioprotectant
of trehalose has been ascribed to this tight coupling, since the appearance of damages on biological structures will more
involve structural variations of the surrounding matrix. Here we present, as an applicative follow-up of this research line,
a Fourier transform infrared study on protein–matrix coupling in commercial maltodextrins and trehalosyldextrins solid amorphous
systems, with carboxymyoglobin embedded, and compare the results with analogous system containing trehalose and maltose, previously
reported. Results point out that trehalosyldextrins are useful candidates as protecting agents, even though with an efficiency
lower than trehalose, and could be used when the rheological properties of relative long-chain oligosaccharides are needed.
However, it appears that a substantial improvement could be obtained by removal of the small fraction of glucose. 相似文献
75.
Porri A Baroncelli R Guglielminetti L Sarrocco S Guazzelli L Forti M Catelani G Valentini G Bazzichi A Franceschi M Vannacci G 《Fungal biology》2011,115(1):30-37
Degradation and detoxification of textile dyes are of interest due to the huge environmental impact of such chemicals. An isolate of Fusarium oxysporum was used to degrade and to detoxify a new chemical class of textile dyes called Glycoconjugate Azo Dye (GAD). After 6 d of growth in a liquid batch culture, the fungus degraded the dye and the culture medium at the end of incubation period showed a ?100% detoxification compared to the initial dye solution. Increasing the initial fungal inoculum, the dye was totally decolourized after 24 h of incubation. The degradation ability was found to be common among various isolates of F. oxysporum suggesting this as a specific trait of this species. Degrading rate was enhanced in concomitancy to the glucose depletion and the beginning of the stationary phase of growth, suggesting that the shift from the primary to the secondary metabolism may be the trigger of the degradation pathway. The Daphnia magna acute toxicity test demonstrated a strong detoxification of GAD-4 by F. oxysporum, resulting in non-toxic metabolite production. Fusarium oxysporum could, therefore, be taken into consideration to develop new remediation strategies of textile effluents. 相似文献
76.
Cristina Gervasoni Paola Meraviglia Simona Landonio Sara Baldelli Serena Fucile Laura Castagnoli Emilio Clementi Agostino Riva Massimo Galli Giuliano Rizzardini Dario Cattaneo 《PloS one》2013,8(12)
Treatment with tenofovir sometimes leads to non-reversible kidney and/or bone diseases. Factors associated with these drug-related adverse events are poorly characterized. Our objective was to investigate such factors in patients treated long term with daily tenofovir. One-hundred Caucasian HIV-positive patients with basal creatinine clearance >80 mL/min treated with tenofovir for at least 6 months and with at least one assessment of tenofovir plasma trough concentrations were considered. Tenofovir-associated adverse events were defined as the appearance of pathological proteinuria, worsening of renal function or bone demineralization. By multivariate regression analysis, we found that serum creatinine (p = 0.003) and body weight (p = 0.002) were the factors independently associated with plasma tenofovir concentrations. In particular, women with body weight<50 kg had significantly higher plasma tenofovir concentrations than those weighting >50 Kg (160±93 vs.71±52 ng/mL, p<0.001). High tenofovir plasma trough concentrations and the age of the patients were independently associated with the development of drug-related kidney and bone toxicity. In this retrospective study we have shown that HIV-infected women with low body weight are at risk to be exposed to high tenofovir plasma trough concentrations, ultimately resulting in a significant hazard to develop long-term tenofovir complications. 相似文献
77.
Docking is a computational technique that places a small molecule (ligand) in the binding site of its macromolecular target (receptor) and estimates its binding affinity. This review addresses methodological developments that have occurred in the docking field in 2009, with a particular focus on the more difficult, and sometimes controversial, aspects of this promising computational discipline. These developments aim to address the main challenges of docking: receptor representation (such aspects as structural waters, side chain protonation, and, most of all, flexibility (from side chain rotation to domain movement)), ligand representation (protonation, tautomerism and stereoisomerism, and the effect of input conformation), as well as accounting for solvation and entropy of binding. This review is strongly focused on docking advances in the context of drug design, specifically in virtual screening and fragment-based drug design. 相似文献
78.
79.
Mapelli F Marasco R Rizzi A Baldi F Ventura S Daffonchio D Borin S 《Microbial ecology》2011,61(2):438-447
In arctic glacier moraines, bioweathering primed by microbial iron oxidizers creates fertility gradients that accelerate soil
development and plant establishment. With the aim of investigating the change of bacterial diversity in a pyrite-weathered
gradient, we analyzed the composition of the bacterial communities involved in the process by sequencing 16S rRNA gene libraries
from different biological soil crusts (BSC). Bacterial communities in three BSC of different morphology, located within 1 m
distance downstream a pyritic conglomerate rock, were significantly diverse. The glacier moraine surrounding the weathered
site showed wide phylogenetic diversity and high evenness with 15 represented bacterial classes, dominated by Alphaproteobacteria
and pioneer Cyanobacteria colonizers. The bioweathered area showed the lowest diversity indexes and only nine bacterial families,
largely dominated by Acidobacteriaceae and Acetobacteraceae typical of acidic environments, in accordance with the low pH of the BSC. In the weathered BSC, iron-oxidizing bacteria were
cultivated, with counts decreasing along with the increase of distance from the rock, and nutrient release from the rock was
revealed by environmental scanning electron microscopy-energy dispersive X-ray analyses. The vegetated area showed the presence
of Actinomycetales, Verrucomicrobiales, Gemmatimonadales, Burkholderiales, and Rhizobiales, denoting a bacterial community typical of developed soils and indicating that the lithoid substrate of the bare moraine
was here subjected to an accelerated colonization, driven by iron-oxidizing activity. 相似文献
80.
Hanjie Jiang Claire Y. Chiang Zan Chen Sara Nathan Gabriel DAgostino Joao A. Paulo Guang Song Heng Zhu Sandra B. Gabelli Philip A. Cole 《The Journal of biological chemistry》2022,298(5)
WWP2 is a HECT E3 ligase that targets protein Lys residues for ubiquitination and is comprised of an N-terminal C2 domain, four central WW domains, and a C-terminal catalytic HECT domain. The peptide segment between the middle WW domains, the 2,3-linker, is known to autoinhibit the catalytic domain, and this autoinhibition can be relieved by phosphorylation at Tyr369. Several protein substrates of WWP2 have been identified, including the tumor suppressor lipid phosphatase PTEN, but the full substrate landscape and biological functions of WWP2 remain to be elucidated. Here, we used protein microarray technology and the activated enzyme phosphomimetic mutant WWP2Y369E to identify potential WWP2 substrates. We identified 31 substrate hits for WWP2Y369E using protein microarrays, of which three were known autophagy receptors (NDP52, OPTN, and SQSTM1). These three hits were validated with in vitro and cell-based transfection assays and the Lys ubiquitination sites on these proteins were mapped by mass spectrometry. Among the mapped ubiquitin sites on these autophagy receptors, many had been previously identified in the endogenous proteins. Finally, we observed that WWP2 KO SH-SH5Y neuroblastoma cells using CRISPR-Cas9 showed a defect in mitophagy, which could be rescued by WWP2Y369E transfection. These studies suggest that WWP2-mediated ubiquitination of the autophagy receptors NDP52, OPTN, and SQSTM1 may positively contribute to the regulation of autophagy 相似文献