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61.
62.
Atilla Akdemir Daniela Vullo Viviana De Luca Andrea Scozzafava Vincenzo Carginale Mosè Rossi Claudiu T. Supuran Clemente Capasso 《Bioorganic & medicinal chemistry letters》2013,23(4):1087-1090
The α-carbonic anhydrase (CA, EC 4.2.1.1) from the extremophilic bacterium Sulfurihydrogenibium azorense (SazCA) was recently shown to be the fastest CA known. Here we investigated this enzyme for its activation with a series of amino acids and amines. The best SazCA activators were d-Phe, l-DOPA, l- and d-Trp, dopamine and serotonin, which showed activation constants in the range of 3–23 nM. l- and d-His, l-Phe, l-Tyr, 2-pyridyl-methylamine and L-adrenaline were also effective activators (KAs in the range of 62–90 nM), whereas d-Dopa, d-Tyr and several heterocyclic amines showed activity in the micromolar range. The good thermal stability, robustness, very high catalytic activity and propensity to be activated by simple amino acids and amines, make SazCA a very interesting candidate for biomimetic CO2 capture processes. 相似文献
63.
Francesca Megiorni Giovanni Luca Gravina Simona Camero Simona Ceccarelli Andrea Del Fattore Vincenzo Desiderio Federica Papaccio Heather P. McDowell Rajeev Shukla Antonio Pizzuti Filip Beirinckx Philippe Pujuguet Laurent Saniere Ellen Van der Aar Roberto Maggio Francesca De Felice Cinzia Marchese Carlo Dominici Vincenzo Tombolini Claudio Festuccia Francesco Marampon 《Journal of hematology & oncology》2017,10(1):161
Background
EPH (erythropoietin-producing hepatocellular) receptors are clinically relevant targets in several malignancies. This report describes the effects of GLPG1790, a new potent pan-EPH inhibitor, in human embryonal rhabdomyosarcoma (ERMS) cell lines.Methods
EPH-A2 and Ephrin-A1 mRNA expression was quantified by real-time PCR in 14 ERMS tumour samples and in normal skeletal muscle (NSM). GLPG1790 effects were tested in RD and TE671 cell lines, two in vitro models of ERMS, by performing flow cytometry analysis, Western blotting and immunofluorescence experiments. RNA interfering experiments were performed to assess the role of specific EPH receptors. Radiations were delivered using an x-6 MV photon linear accelerator. GLPG1790 (30 mg/kg) in vivo activity alone or in combination with irradiation (2 Gy) was determined in murine xenografts.Results
Our study showed, for the first time, a significant upregulation of EPH-A2 receptor and Ephrin-A1 ligand in ERMS primary biopsies in comparison to NSM. GLPG1790 in vitro induced G1-growth arrest as demonstrated by Rb, Cyclin A and Cyclin B1 decrease, as well as by p21 and p27 increment. GLPG1790 reduced migratory capacity and clonogenic potential of ERMS cells, prevented rhabdosphere formation and downregulated CD133, CXCR4 and Nanog stem cell markers. Drug treatment committed ERMS cells towards skeletal muscle differentiation by inducing a myogenic-like phenotype and increasing MYOD1, Myogenin and MyHC levels. Furthermore, GLPG1790 significantly radiosensitized ERMS cells by impairing the DNA double-strand break repair pathway. Silencing of both EPH-A2 and EPH-B2, two receptors preferentially targeted by GLPG1790, closely matched the effects of the EPH pharmacological inhibition. GLPG1790 and radiation combined treatments reduced tumour mass by 83% in mouse TE671 xenografts.Conclusions
Taken together, our data suggest that altered EPH signalling plays a key role in ERMS development and that its pharmacological inhibition might represent a potential therapeutic strategy to impair stemness and to rescue myogenic program in ERMS cells.64.
Valentina Ferrari Alison Tarke Hannah Fields Luca Ferrari Trevor Conley Franco Ferrari Zeynep Koşaloğlu-Yalçın Alessandro Sette Bjoern Peters Colin L. McCarthy Asad Bashey Dimitrios Tzachanis Edward D. Ball Tiffany N. Tanaka Rafael Bejar Thomas A. Lane Antonella Vitiello 《Cytotherapy》2021,23(4):320-328
Therapies that utilize immune checkpoint inhibition work by leveraging mutation-derived neoantigens and have shown greater clinical efficacy in tumors with higher mutational burden. Whether tumors with a low mutational burden are susceptible to neoantigen-targeted therapy has not been fully addressed. To examine the feasibility of neoantigen-specific adoptive T-cell therapy, the authors studied the T-cell response against somatic variants in five patients with myelodysplastic syndrome (MDS), a malignancy with a very low tumor mutational burden. DNA and RNA from tumor (CD34+) and normal (CD3+) cells isolated from the patients’ blood were sequenced to predict patient-specific MDS neopeptides. Neopeptides representing the somatic variants were used to induce and expand autologous T cells ex vivo, and these were systematically tested in killing assays to determine the proportion of neopeptides yielding neoantigen-specific T cells. The authors identified a total of 32 somatic variants (four to eight per patient) and found that 21 (66%) induced a peptide-specific T-cell response and 19 (59%) induced a T-cell response capable of killing autologous tumor cells. Of the 32 somatic variants, 11 (34%) induced a CD4+ response and 11 (34%) induced a CD8+ response that killed the tumor. These results indicate that in vitro induction of neoantigen-specific T cells is feasible for tumors with very low mutational burden and that this approach warrants investigation as a therapeutic option for such patients. 相似文献
65.
Marco Camanni Luca Bonino Elena Maria Delpiano Paola Berchialla Giuseppe Migliaretti Alberto Revelli Francesco Deltetto 《Reproductive biology and endocrinology : RB&E》2009,7(1):109-7
Background
this study aims to evaluate the effectiveness and safety of laparoscopic conservative management of ureteral endometriosis. 相似文献66.
In Southern Italy, an endemic monotypic genus belonging to family Apiaceae occurs: Petagnaea (P. gussonei), relict of Tertiary flora, belonging to subfamily Saniculoideae. At present, P. gussonei is an endangered species and is included in various lists of species deserving special protection. The genus belongs to scapose hemicryptophytes and shares a sciaphilous habitat (hygrophilous woodland). This study is aimed at doing a complete contribution about the evolutionary history of Petagnaea, using molecular markers as plastidial DNA (cpDNA), nuclear ribosomal DNA (rDNA) and data present in literature. We used nucleotide sequences from four regions of the chloroplast genome (rps16 intron, trnL(UAA) intron, atpB-rbcL intergenic spacer, and partial matK gene) to investigate possible haplotypes in Petagnaea populations. To have an idea of the molecular relationships of all populations of P. gussonei, the internal transcribed spacer (ITS) sequences, already employed in recent studies, were obtained for 18 populations. These sequences in combination with other Saniculoideae ITS sequences available from GenBank have been used for a further phylogenetic analysis. The results agree with the current classification of Saniculoideae in placing P. gussonei in tribe Saniculeae, since P. gussonei is in basal position to Sanicula. According to intraspecific chloroplast DNA diversity, no different haplotypes were detected. In addition to molecular data, morphology, cytology, phytochemistry and conservation status have been considered in the discussion. 相似文献
67.
Passeri Elena Bonomi Marco Dangelo Francesco Persani Luca Corbetta Sabrina 《BMC endocrine disorders》2014,14(1):1-4
Background
Non-thyroidal illness (NTI) refers to changes in thyroid hormone levels in critically ill patients in the absence of primary hypothalamic-pituitary-thyroid dysfunction, and these abnormalities usually resolve after clinical recovery. However, NTI can be accompanied by primary thyroid dysfunction. We report herein a case of a woman with NTI accompanied by primary hyperthyroidism.Case presentation
A 52-year-old female was admitted to the intensive care unit with heart failure and atrial fibrillation. She had a longstanding thyroid nodule, and a thyroid function test revealed low levels of triiodothyronine and free thyroxine as well as undetectable thyroid stimulating hormone (TSH). She was diagnosed with NTI, and her TSH level began to recover but not completely at discharge. The thyroid function test was repeated after 42 months to reveal primary hyperthyroidism, and a thyroid scan confirmed a toxic nodule.Conclusion
This case suggests that although NTI was diagnosed, primary hyperthyroidism should be considered as another possible diagnosis if TSH is undetectable. Thyroid function tests should be repeated after clinical recovery from acute illness. 相似文献68.
Lungfish (Dipnoi) are the closest living relatives to tetrapods, and they represent the transition from water to land during vertebrate evolution. Lungfish are armed with immunoglobulins (Igs), one of the hallmarks of the adaptive immune system of jawed vertebrates, but only three Ig forms have been characterized in Dipnoi to date. We report here a new diversity of Ig molecules in two African lungfish species (Protopterus dolloi and Protopterus annectens). The African lungfish Igs consist of three IgMs, two IgWs, three IgNs, and an IgQ, where both IgN and IgQ originated evidently from the IgW lineage. Our data also suggest that the IgH genes in the lungfish are organized in a transiting form from clusters (IgH loci in cartilaginous fish) to a translocon configuration (IgH locus in tetrapods). We propose that the intraclass diversification of the two primordial gnathostome Ig classes (IgM and IgW) as well as acquisition of new isotypes (IgN and IgQ) has allowed lungfish to acquire a complex and functionally diverse Ig repertoire to fight a variety of microorganisms. Furthermore, our results support the idea that “tetrapod-specific” Ig classes did not evolve until the vertebrate adaptation to land was completed ~360 million years ago. 相似文献
69.
70.
Japanese encephalitis virus (JEV) is the leading global cause of viral encephalitis. The JEV envelope protein (E) facilitates cellular attachment and membrane fusion and is the primary target of neutralizing antibodies. We have determined the 2.1-Å resolution crystal structure of the JEV E ectodomain refolded from bacterial inclusion bodies. The E protein possesses the three domains characteristic of flavivirus envelopes and epitope mapping of neutralizing antibodies onto the structure reveals determinants that correspond to the domain I lateral ridge, fusion loop, domain III lateral ridge, and domain I-II hinge. While monomeric in solution, JEV E assembles as an antiparallel dimer in the crystal lattice organized in a highly similar fashion as seen in cryo-electron microscopy models of mature flavivirus virions. The dimer interface, however, is remarkably small and lacks many of the domain II contacts observed in other flavivirus E homodimers. In addition, uniquely conserved histidines within the JEV serocomplex suggest that pH-mediated structural transitions may be aided by lateral interactions outside the dimer interface in the icosahedral virion. Our results suggest that variation in dimer structure and stability may significantly influence the assembly, receptor interaction, and uncoating of virions. 相似文献