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131.
Vdo C Souza KB Schlemmer CB Noal JA Jaques CE Zimmermann CA Leal J Fleck EA Casali VM Morsch MR Schetinger DB Leal 《Parasitology international》2012,61(4):690-696
Trypanosoma cruzi infection triggers a chronic inflammatory process in human host and purinergic system ecto-enzymes play an important role in modulating the inflammatory and immune responses. In this study, it was investigated ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase; EC 3.6.1.5; CD39) and ecto-adenosine deaminase (E-ADA; EC 3.5.4.4) activities in lymphocytes from patients with indeterminate form of Chagas' disease (IFCD). Twenty-five IFCD patients and 25 healthy subjects (control group) were selected. The peripheral lymphocytes were isolated and E-NTPDase and E-ADA activities were determined. Adenine nucleotides and adenosine levels were determined in serum by HPLC and the E-NTPDase1 expression in lymphocytes by Western blot analysis. E-NTPDase (ATP and ADP as substrates) and E-ADA (adenosine as substrate) activities were decreased in lymphocytes from IFCD patients (P<0.05 and P<0.01, respectively), while the E-NTPDase1 expression presented no changes in these patients. Serum ATP levels showed to be decreased (P<0.05) and both AMP (P<0.01) and adenosine (P<0.001) levels were increased in the IFCD group. The enzymatic alterations observed are in agreement with the immune response against T. cruzi infection in IFCD patients, since the decreased extracellular ATP and the increased adenosine levels trigger a Th2 anti-inflammatory response, which it is associated to adaptation of host to parasite, preventing clinical progress of disease. 相似文献
132.
Developmental and Environmental Effects on Sesquiterpene Lactones in Cultivated Arnica montana L. 下载免费PDF全文
Milka Todorova Antoaneta Trendafilova Antonina Vitkova Maria Petrova Ely Zayova Daniela Antonova 《化学与生物多样性》2016,13(8):976-981
The amount of sesquiterpene lactones and the lactone profile of Arnica montana L. in flowering and seed formation stages in vitro and in vivo propagated from seeds of German, Ukrainian, and Austrian origin and grown in two experimental fields were studied. It was found that in vitro propagated 2‐year plants in full flowering stage accumulated higher amount of lactones in comparison to in vivo propagated 3‐year plants and to the seed formation stage, respectively. Helenalins predominated in in vivo propagated 2‐year or in vitro propagated 3‐year plants. 2‐Methylbutyrate (2MeBu) was the principal ester in the samples with prevalence of helenalins, while isobutyrate (iBu) was the major one in the samples with predominance of 11,13‐dihydrohelenalins. The results revealed that the environmental conditions on Vitosha Mt. are more suitable for cultivation of A. montana giving higher content of lactones. 相似文献
133.
Millucci L Paccagnini E Ghezzi L Bernardini G Braconi D Laschi M Consumi M Spreafico A Tanganelli P Lupetti P Magnani A Santucci A 《PloS one》2011,6(7):e21870
Aims
Atrial Natriuretic Peptide (ANP)-containing amyloid is frequently found in the elderly heart. No data exist regarding ANP aggregation process and its link to pathologies. Our aims were: i) to experimentally prove the presumptive association of Congestive Heart Failure (CHF) and Isolated Atrial Amyloidosis (IAA); ii) to characterize ANP aggregation, thereby elucidating IAA implication in the CHF pathogenesis.Methods and Results
A significant prevalence (85%) of IAA was immunohistochemically proven ex vivo in biopsies from CHF patients. We investigated in vitro (using Congo Red, Thioflavin T, SDS-PAGE, transmission electron microscopy, infrared spectroscopy) ANP fibrillogenesis, starting from α-ANP as well as the ability of dimeric β-ANP to promote amyloid formation. Different conditions were adopted, including those reproducing β-ANP prevalence in CHF. Our results defined the uncommon rapidity of α-ANP self-assembly at acidic pH supporting the hypothesis that such aggregates constitute the onset of a fibrillization process subsequently proceeding at physiological pH. Interestingly, CHF-like conditions induced the production of the most stable and time-resistant ANP fibrils suggesting that CHF affected people may be prone to develop IAA.Conclusions
We established a link between IAA and CHF by ex vivo examination and assessed that β-ANP is, in vitro, the seed of ANP fibrils. Our results indicate that β-ANP plays a crucial role in ANP amyloid deposition under physiopathological CHF conditions. Overall, our findings indicate that early IAA-related ANP deposition may occur in CHF and suggest that these latter patients should be monitored for the development of cardiac amyloidosis. 相似文献134.
The peculiar heme pocket of the 2/2 hemoglobin of cold-adapted Pseudoalteromonas haloplanktis TAC125
Barry D. Howes Daniela Giordano Leonardo Boechi Roberta Russo Simona Mucciacciaro Chiara Ciaccio Federica Sinibaldi Maria Fittipaldi Marcelo A. Mart�� Dar��o A. Estrin Guido di Prisco Massimo Coletta Cinzia Verde Giulietta Smulevich 《Journal of biological inorganic chemistry》2011,16(2):299-311
The genome of the cold-adapted bacterium Pseudoalteromonas haloplanktis TAC125 contains multiple genes encoding three distinct monomeric hemoglobins exhibiting a 2/2 ??-helical fold. In the present work, one of these hemoglobins is studied by resonance Raman, electronic absorption and electronic paramagnetic resonance spectroscopies, kinetic measurements, and different bioinformatic approaches. It is the first cold-adapted bacterial hemoglobin to be characterized. The results indicate that this protein belongs to the 2/2 hemoglobin family, Group II, characterized by the presence of a tryptophanyl residue on the bottom of the heme distal pocket in position G8 and two tyrosyl residues (TyrCD1 and TyrB10). However, unlike other bacterial hemoglobins, the ferric state, in addition to the aquo hexacoordinated high-spin form, shows multiple hexacoordinated low-spin forms, where either TyrCD1 or TyrB10 can likely coordinate the iron. This is the first example in which both TyrCD1 and TyrB10 are proposed to be the residues that are alternatively involved in heme hexacoordination by endogenous ligands. 相似文献
135.
AIDS Vaccination Studies Using an Ex Vivo Feline Immunodeficiency Virus Model: Detailed Analysis of the Humoral Immune Response to a Protective Vaccine 总被引:1,自引:0,他引:1 下载免费PDF全文
136.
Roldan M de Guia Adam J Rose Anke Sommerfeld Oksana Seibert Daniela Strzoda Annika Zota Yvonne Feuchter Anja Krones‐Herzig Tjeerd Sijmonsma Milen Kirilov Carsten Sticht Norbert Gretz Geesje Dallinga‐Thie Sven Diederichs Nora Klöting Matthias Blüher Mauricio Berriel Diaz Stephan Herzig 《The EMBO journal》2015,34(3):344-360
In mammals, glucocorticoids (GCs) and their intracellular receptor, the glucocorticoid receptor (GR), represent critical checkpoints in the endocrine control of energy homeostasis. Indeed, aberrant GC action is linked to severe metabolic stress conditions as seen in Cushing's syndrome, GC therapy and certain components of the Metabolic Syndrome, including obesity and insulin resistance. Here, we identify the hepatic induction of the mammalian conserved microRNA (miR)‐379/410 genomic cluster as a key component of GC/GR‐driven metabolic dysfunction. Particularly, miR‐379 was up‐regulated in mouse models of hyperglucocorticoidemia and obesity as well as human liver in a GC/GR‐dependent manner. Hepatocyte‐specific silencing of miR‐379 substantially reduced circulating very‐low‐density lipoprotein (VLDL)‐associated triglyceride (TG) levels in healthy mice and normalized aberrant lipid profiles in metabolically challenged animals, mediated through miR‐379 effects on key receptors in hepatic TG re‐uptake. As hepatic miR‐379 levels were also correlated with GC and TG levels in human obese patients, the identification of a GC/GR‐controlled miRNA cluster not only defines a novel layer of hormone‐dependent metabolic control but also paves the way to alternative miRNA‐based therapeutic approaches in metabolic dysfunction. 相似文献
137.
gp190 is a glycoprotein expressed on the cell surface of several human colon carcinoma cells in culture, on epithelial cells of fetal colon, but not on the normal mucosa of adult colon; thus it is referred to as an oncofetal crypt cell antigen. We report the characterisation of O[emsp4 ]-linked glycans carried by gp190 synthesised by [3H]glucosamine-labelled Caco-2 cells at the confluence (undifferentiated cells) and at three weeks of postconfluence (differentiated cells). By using a specific monoclonal antibody, gp190 was isolated and analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The mobility of gp190 from differentiated cells was found to be lower than that from undifferentiated cells, suggesting a more extensive glycosylation process in the former glycoprotein. The major results of the glycan characterisation have been as follows: (i) gp190 carries mainly, if not exclusively, O-linked glycans with the core-2 structure; (ii) the elongation with N-acetyllactosamine units of the Gal1,4GlcNAc1,6(Gal1,3)GalNAc tetrasaccharide predominates in gp190 synthesised by differentiated cells, whereas the direct 2,3sialylation of the tetrasaccharide is prevalent in gp190 synthesised by undifferentiated cells. The increment in the core-2 1,6GlcNAc-transferase activity under the Caco-2 differentiation process may be relevant in producing the larger occurrence of polylactosaminoglycans in gp190 from differentiated cells. Since no change in the activity of the 2,3sialyltransferases upon cell differentiation was observed, we suggest that the lower 2,3sialylation in gp190 synthesised by polarised cells might be due to a changed transit-rate through the distal Golgi apparatus. 相似文献
138.
Maurecilne Lemes da Silva Daniela Lopes Paim Pinto Miguel Pedro Guerra Eny Iochevet Segal Floh Cláudio Horst Bruckner Wagner Campos Otoni 《Plant Cell, Tissue and Organ Culture》2009,99(1):47-54
The objective of the present work was to induce somatic embryogenesis from zygotic embryos of Passiflora cincinnata Masters. Zygotic embryos formed calli on media with different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and
4.5 μM benzyladenine (BA) after 30 days of in vitro culture. A concentration of 18.1 μM 2,4-D resulted in the largest number
of somatic embryos. Embryogenic calli were yellowish and friable, forming whitish proembryogenic masses. Morphologically,
embryogenic cells were small and had large nuclei and dense cytoplasm, whereas non-embryogenic cells were elongated, with
small nuclei and less dense cytoplasm. Calli cultured under white light on basal Murashige and Skoog’s medium with activated
charcoal produced embryos in all developmental stages. There were differences among the treatments, with some leading to the
production of calli with embryos and some only to callus formation. Some abnormalities were associated with somatic embryos,
including fused axes, fused cotyledons and polycotyledonary embryos. Production of secondary somatic embryos occurred in the
first cycle of primary embryo development. Secondary embryos differentiated from the surface of the protodermal layer of primary
embryos with intense cell proliferation, successive mitotic divisions in the initial phase of embryoid development, and a
vascular system formed with no connection to the parental tissue. This secondary embryogenic system of P. cincinnata is characterized by intense proliferation and maintenance of embryogenic competence after successive subcultures. This reproducible
protocol opens new prospects for massive propagation and is an alternative to the current organogenesis-based transformation
protocol. 相似文献
139.
Ng CA Hunter MJ Perry MD Mobli M Ke Y Kuchel PW King GF Stock D Vandenberg JI 《PloS one》2011,6(1):e16191
The cytoplasmic N-terminal domain of the human ether-a-go-go related gene (hERG) K+ channel is critical for the slow deactivation kinetics of the channel. However, the mechanism(s) by which the N-terminal domain regulates deactivation remains to be determined. Here we show that the solution NMR structure of the N-terminal 135 residues of hERG contains a previously described Per-Arnt-Sim (PAS) domain (residues 26-135) as well as an amphipathic α-helix (residues 13-23) and an initial unstructured segment (residues 2-9). Deletion of residues 2-25, only the unstructured segment (residues 2-9) or replacement of the α-helix with a flexible linker all result in enhanced rates of deactivation. Thus, both the initial flexible segment and the α-helix are required but neither is sufficient to confer slow deactivation kinetics. Alanine scanning mutagenesis identified R5 and G6 in the initial flexible segment as critical for slow deactivation. Alanine mutants in the helical region had less dramatic phenotypes. We propose that the PAS domain is bound close to the central core of the channel and that the N-terminal α-helix ensures that the flexible tail is correctly orientated for interaction with the activation gating machinery to stabilize the open state of the channel. 相似文献
140.
Daniela Bustos‐Korts Ian K. Dawson Joanne Russell Alessandro Tondelli Davide Guerra Chiara Ferrandi Francesco Strozzi Ezequiel L. Nicolazzi Marta Molnar‐Lang Hakan Ozkan Maria Megyeri Peter Miko Esra akr Enes Yakr Noemi Trabanco Stefano Delbono Stylianos Kyriakidis Allan Booth Davide Cammarano Martin Mascher Peter Werner Luigi Cattivelli Laura Rossini Nils Stein Benjamin Kilian Robbie Waugh Fred A. van Eeuwijk 《The Plant journal : for cell and molecular biology》2019,99(6):1172-1191
Broadening the genetic base of crops is crucial for developing varieties to respond to global agricultural challenges such as climate change. Here, we analysed a diverse panel of 371 domesticated lines of the model crop barley to explore the genetics of crop adaptation. We first collected exome sequence data and phenotypes of key life history traits from contrasting multi‐environment common garden trials. Then we applied refined statistical methods, including some based on exomic haplotype states, for genotype‐by‐environment (G×E) modelling. Sub‐populations defined from exomic profiles were coincident with barley's biology, geography and history, and explained a high proportion of trial phenotypic variance. Clear G×E interactions indicated adaptation profiles that varied for landraces and cultivars. Exploration of circadian clock‐related genes, associated with the environmentally adaptive days to heading trait (crucial for the crop's spread from the Fertile Crescent), illustrated complexities in G×E effect directions, and the importance of latitudinally based genic context in the expression of large‐effect alleles. Our analysis supports a gene‐level scientific understanding of crop adaption and leads to practical opportunities for crop improvement, allowing the prioritisation of genomic regions and particular sets of lines for breeding efforts seeking to cope with climate change and other stresses. 相似文献