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51.
Daniele De Simone Lorella D’Amico Daniela Bressanin Emma Motta Tiziana Annesi 《Mycological Progress》2011,10(3):301-306
Thirteen isolates of Inonotus rickii/Ptychogaster cubensis, from different geographic provenances, were analyzed by sequencing ITS1, ITS 2 and 5,8S ribosomal RNA region. A phylogenetic
tree, also including sequences available in Genbank database, showed that the strains enclosed in this study fall into two
well-separated groups, one formed by isolates from Florida (USA) and the other one by isolates from Europe, Argentina and
China. Differences were also highlighted on the growth rate of mycelial cultures at different temperatures. In fact, although
the tested isolates generally attained the best growth at 30°C, isolates from Europe seem well adapted to higher temperatures
and went on growing at 40°C whilst the growth of isolates from Florida significantly decreased at 35°C. Since the teleomorph
I. rickii was never detected in Florida, and in this study noticeable differences were detected by analysis of ITS region, the existence
of two possible distinct species, not discriminated solely on the basis of morphological characters, could be suggested. 相似文献
52.
Simone Mohren Ralf Weiskirchen 《Biochemical and biophysical research communications》2009,379(4):1015-1020
We have demonstrated that gene polymorphisms within the N-terminal leader sequence of TGF-β1 contribute to the outcome of hepatic fibrogenesis. In addition, the polymorphism at codon 25 affects TGF-β1 production in peripheral blood leukocytes. Therefore, it is general assumed that these polymorphisms influence cellular secretion of this cytokine. In the present study, we analysed if this widespread hypothesis is true. We cloned FLAG-tagged CMV-driven human full-length TGF-β1 expression constructs of the different allelic variations (i.e. 10Leu/25Arg, 10Pro/25Pro and 10Pro/25Arg) and transfected them into the immortal hepatic stellate cell line LX-2 and Chinese Hamster Ovary cells. Surprisingly, the allelic variants carrying a proline either in codon 10 or 25 showed overall reduced expression as assessed by Western blot and quantitative ELISA. We conclude that the allelic variations within the signal sequence influence the expression and not secretion of TGF-β1. Detailed RNA structure prediction analysis further suggests that the individual variants form different secondary structures. 相似文献
53.
Asmita Banerjee Sylvia Nürnberger Simone Hennerbichler Sabrina Riedl Christina M. A. P. Schuh Ara Hacobian Andreas Teuschl Johann Eibl Heinz Redl Susanne Wolbank 《Cell and tissue banking》2014,15(2):227-239
Human amniotic membrane (hAM) is a tissue containing cells with proven stem cell properties. In its decellularized form it has been successfully applied as nerve conduit biomaterial to improve peripheral nerve regeneration in injury models. We hypothesize that viable hAM without prior cell isolation can be differentiated towards the Schwann cell lineage to generate a possible alternative to commonly applied tissue engineering materials for nerve regeneration. For in vitro Schwann cell differentiation, biopsies of hAM of 8 mm diameter were incubated with a sequential order of neuronal induction and growth factors for 21 days and characterized for cellular viability and the typical glial markers glial fibrillary acidic protein (GFAP), S100β, p75 and neurotrophic tyrosine kinase receptor (NTRK) using immunohistology. The secretion of the neurotrophic factors brain-derived neurotrophic factor (BDNF) and glial cell-derived neurotrophic factor (GDNF) was quantified by ELISA. The hAM maintained high viability, especially under differentiation conditions (90.2 % ± 41.6 day 14; 80.0 % ± 44.5 day 21 compared to day 0). Both, BDNF and GDNF secretion was up-regulated upon differentiation. The fresh membrane stained positive for GFAP and p75 and NTRK, which was strongly increased after culture in differentiation conditions. Especially the epithelial layer within the membrane exhibited a change in morphology upon differentiation forming a multi-layered epithelium with intense accumulations of the marker proteins. However, S100β was expressed at equal levels and equal distribution in fresh and cultured hAM conditions. Viable hAM may be a promising alternative to present formulations used for peripheral nerve regeneration. 相似文献
54.
In a batch cultivation of Pichia pastoris expressing Candida rugosa lipase 1 (CRL1), secretion of 200 microg lipase ml(-1) of culture was achieved in sorbitol-based medium. However, a large amount of recombinant protein was retained intracellularly throughout the fermentation, pointing to the transport step as a major bottleneck. Therefore a translational fusion with the green fluorescent protein (GFP) was constructed that was expressed and transported similarly to the native lipase and retained catalytic activity. This analytical tool enables a rapid monitoring of product localization and amount, based on GFP-associated fluorescence. 相似文献
55.
56.
Sayantani Chatterjee Ling Y. Lee Rebeca Kawahara Jodie L. Abrahams Barbara Adamczyk Merrina Anugraham Christopher Ashwood Zeynep Sumer‐Bayraktar Matthew T. Briggs Jenny H. L. Chik Arun Everest‐Dass Sarah Frster Hannes Hinneburg Katia R. M. Leite Ian Loke Uwe Mginger Edward S. X. Moh Miyako Nakano Saulo Recuero Manveen K. Sethi Miguel Srougi Kathrin Stavenhagen Vignesh Venkatakrishnan Katherine Wongtrakul‐Kish Simone Diestel Peter Hoffmann Niclas G. Karlsson Daniel Kolarich Mark P. Molloy Michael H. Muders Martin K. Oehler Nicolle H. Packer Giuseppe Palmisano Morten Thaysen‐Andersen 《Proteomics》2019,19(21-22)
While aberrant protein glycosylation is a recognized characteristic of human cancers, advances in glycoanalytics continue to discover new associations between glycoproteins and tumorigenesis. This glycomics‐centric study investigates a possible link between protein paucimannosylation, an under‐studied class of human N‐glycosylation [Man1‐3GlcNAc2Fuc0‐1], and cancer. The paucimannosidic glycans (PMGs) of 34 cancer cell lines and 133 tissue samples spanning 11 cancer types and matching non‐cancerous specimens are profiled from 467 published and unpublished PGC‐LC‐MS/MS N‐glycome datasets collected over a decade. PMGs, particularly Man2‐3GlcNAc2Fuc1, are prominent features of 29 cancer cell lines, but the PMG level varies dramatically across and within the cancer types (1.0–50.2%). Analyses of paired (tumor/non‐tumor) and stage‐stratified tissues demonstrate that PMGs are significantly enriched in tumor tissues from several cancer types including liver cancer (p = 0.0033) and colorectal cancer (p = 0.0017) and is elevated as a result of prostate cancer and chronic lymphocytic leukaemia progression (p < 0.05). Surface expression of paucimannosidic epitopes is demonstrated on human glioblastoma cells using immunofluorescence while biosynthetic involvement of N‐acetyl‐β‐hexosaminidase is indicated by quantitative proteomics. This intriguing association between protein paucimannosylation and human cancers warrants further exploration to detail the biosynthesis, cellular location(s), protein carriers, and functions of paucimannosylation in tumorigenesis and metastasis. 相似文献
57.
Daniela Minerdi Simone Bossi Maria Lodovica Gullino Angelo Garibaldi 《Environmental microbiology》2009,11(4):844-854
Fusarium oxysporum MSA 35 [wild-type (WT) strain] is an antagonistic Fusarium that lives in association with a consortium of bacteria belonging to the genera Serratia, Achromobacter , Bacillus and Stenotrophomonas in an Italian soil suppressive to Fusarium wilt. Typing experiments and virulence tests provided evidence that the F. oxysporum isolate when cured of the bacterial symbionts [the cured (CU) form], is pathogenic, causing wilt symptoms identical to those caused by F. oxysporum f. sp. lactucae . Here, we demonstrate that small volatile organic compounds (VOCs) emitted from the WT strain negatively influence the mycelial growth of different formae speciales of F. oxysporum. Furthermore, these VOCs repress gene expression of two putative virulence genes in F. oxysporum lactucae strain Fuslat10, a fungus against which the WT strain MSA 35 has antagonistic activity. The VOC profile of the WT and CU fungus shows different compositions. Sesquiterpenes, mainly caryophyllene, were present in the headspace only of WT MSA 35. No sesquiterpenes were found in the volatiles of ectosymbiotic Serratia sp. strain DM1 and Achromobacte r sp. strain MM1. Bacterial volatiles had no effects on the growth of the different ff. spp. of F. oxysporum examined. Hyphae grown with VOC from WT F. oxysporum f. sp. lactucae strain MSA 35 were hydrophobic whereas those grown without VOCs were not, suggesting a correlation between the presence of volatiles in the atmosphere and the phenotype of the mycelium. This is the first report of VOC production by antagonistic F. oxysporum MSA 35 and their effects on pathogenic F. oxysporum. The results obtained in this work led us to propose a new potential direct long-distance mechanism for antagonism by F. oxysporum MSA 35 mediated by VOCs . Antagonism could be the consequence of both reduction of pathogen mycelial growth and inhibition of pathogen virulence gene expression. 相似文献
58.
Rational design of Salmonella-based vaccination strategies 总被引:3,自引:0,他引:3
A permanently growing body of information is becoming available about the quality of protective immune responses induced by mucosal immunization. Attenuated live bacterial vaccines can be administered orally and induce long-lasting protective immunity in humans without causing major side effects. An attenuated Salmonella enterica serovar Typhi strain is registered as live oral vaccine against typhoid fever and has been in use for more than two decades. Recombinant attenuated Salmonella strains are also an attractive means of delivering heterologous antigens to the immune system, thereby, stimulating strong mucosal and systemic immune responses and consequently provide an efficient platform technology to design novel vaccination strategies. This includes the choice of heterologous protective antigens and their expression under the control of appropriate promoters within the carrier strain. The availability of well-characterized attenuated mutants of Salmonella concomitantly supports fine tuning of immune response triggered against heterologous antigens. Exploring different mucosal sites as a potential route of immunization has to be taken into account as an additional important way to modulate immune responses according to clinical requirements. This article focuses on the rational design of strategies to modulate appropriate immunological effector functions on the basis of selection of (i) attenuating mutations of the Salmonella strains, (ii) specific expression systems for the heterologous antigens, and (iii) route of mucosal administration. 相似文献
59.
60.
Stefania Raimondo Ornella Urzì Serena Meraviglia Marta Di Simone Anna Maria Corsale Nima Rabienezhad Ganji Antonio Palumbo Piccionello Giulia Polito Elena Lo Presti Francesco Dieli Alice Conigliaro Riccardo Alessandro 《Journal of cellular and molecular medicine》2022,26(15):4195
Chronic inflammation is associated with the occurrence of several diseases. However, the side effects of anti‐inflammatory drugs prompt the identification of new therapeutic strategies. Plant‐derived extracellular vesicles (PDEVs) are gaining increasing interest in the scientific community for their biological properties. We isolated PDEVs from the juice of Citrus limon L. (LEVs) and characterized their flavonoid, limonoid and lipid contents through reversed‐phase high‐performance liquid chromatography coupled to electrospray ionization quadrupole time‐of‐flight mass spectrometry (RP‐HPLC–ESI‐Q‐TOF‐MS). To investigate whether LEVs have a protective role on the inflammatory process, murine and primary human macrophages were pre‐treated with LEVs for 24 h and then were stimulated with lipopolysaccharide (LPS). We found that pre‐treatment with LEVs decreased gene and protein expression of pro‐inflammatory cytokines, such as IL‐6, IL1‐β and TNF‐α, and reduced the nuclear translocation and phosphorylation of NF‐κB in LPS‐stimulated murine macrophages. The inhibition of NF‐κB activation was associated with the reduction in ERK1‐2 phosphorylation. Furthermore, the ability of LEVs to decrease pro‐inflammatory cytokines and increase anti‐inflammatory molecules was confirmed ex vivo in human primary T lymphocytes. In conclusion, we demonstrated that LEVs exert anti‐inflammatory effects both in vitro and ex vivo by inhibiting the ERK1‐2/NF‐κB signalling pathway. 相似文献