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91.
Mauro Pistello Laura Vannucci Alessia Ravani Francesca Bonci Flavia Chiuppesi Barbara Del Santo Giulia Freer Mauro Bendinelli 《Genetic vaccines and therapy》2007,5(1):1-13
Background
Enterovirus 71 (EV71) is a major causative viral agent responsible for large outbreaks of hand, foot and mouth disease (HFMD), a common rash illness in children and infants. There is no effective antiviral treatment for severe EV71 infections and no vaccine is available. The objectives of this study were to design and construct a DNA vaccine against Enterovirus 71 using the viral capsid protein (VP1) gene of EV71 and to verify the functionality of the DNA vaccine in vitro and in vivo.Methods
The VP1 gene of EV71 from two local outbreak isolates were amplified using PCR and then inserted into a eukaryotic expression vector, pVAX1. The 3.9 kb recombinant constructs were transformed into competent E. coli cells and the positive clones were screened and selected using PCR analysis, restriction digestion analysis and DNA sequencing. The constructs were then tested for protein expression in Vero cells. Subsequently, in the in vivo studies, female Balb/c mice were immunized with the DNA vaccine constructs. Enzyme Linked Immunosorbent Assay (ELISA) and virus neutralizing assay were performed to detect the presence of anti-VP1 IgG in mice and its neutralizing effect against the EV71.Results
The pVAX1 vector was successfully cloned with the VP1 gene from each of the isolate (S2/86/1 and 410/4) in the correct orientation and in-frame. The DNA vaccine constructs with the VP1 gene were shown to be expressed in a cell-free in vitro expression system. The VP1 protein was successfully expressed in the mammalian cell line and was detected using RT-PCR, Indirect Immunofluorescence Assay (IFA) and western blotting. The anti-VP1 IgG levels in mice immunized with the DNA vaccine constructs increased after the first booster but declined following the second booster. The anti-VP1 IgG in the mice immunized with the DNA vaccine constructs exhibited neutralising activity against EV71.Conclusion
The promising results obtained in the present study have prompted further testing to improve the expression and immunogenicity of this potential EV71 DNA vaccine. 相似文献92.
Formigari A Irato P Santon A 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2007,146(4):443-459
Copper, zinc and iron are essential metals for different physiological functions, even though their excess can lead to biological damage. This review provides a background of toxicity related to copper, iron and zinc excess, biological mechanisms of their homeostasis and their respective roles in the apoptotic process. The antioxidant action of metallothionein has been highlighted by summarizing the most important findings that confirm the role of zinc in cellular protection in relation to metallothionein expression and apoptotic processes. In particular, we show that a complex and efficient antioxidant system, the induction of metallothionein and the direct action of zinc have protective roles against oxidative damage and the resulting apoptosis induced by metals with redox proprieties. In addition, to emphasize the protective effects of Zn and Zn-MT in Cu and Fe-mediated oxidative stress-dependent apoptosis, some aspects of apoptotic cell death are shown. The most widely used cytochemical techniques also have been examined in order to critically evaluate the available data from a methodological point of view. The observations on the role of Zn and MT could potentially develop new applications for this metal and MT in biomedical research. 相似文献
93.
Constitutive presence of antibiotic resistance genes within the bacterial community of a large subalpine lake 下载免费PDF全文
Andrea Di Cesare Ester M. Eckert Alessia Teruggi Diego Fontaneto Roberto Bertoni Cristiana Callieri Gianluca Corno 《Molecular ecology》2015,24(15):3888-3900
The fate of antibiotic resistance genes (ARGs) in environmental microbial communities is of primary concern as prodromal of a potential transfer to pathogenic bacteria. Although of diverse origin, the persistence of ARGs in aquatic environments is highly influenced by anthropic activities, allowing potential control actions in well‐studied environments. However, knowledge of abundance and space–time distribution of ARGs in ecosystems is still scarce. Using quantitative real‐time PCR, we investigated the presence and the abundance of twelve ARGs (against tetracyclines, β‐lactams, aminoglycosides, quinolones and sulphonamides) at different sampling sites, depths and seasons, in Lake Maggiore, a large subalpine lake, and in the area of its watershed. We then evaluated the correlation between each ARG and a number of ecological parameters in the water column in the deepest part of the lake. Our results suggest the constitutive presence of at least four ARGs within the bacterial community with a high proportion of bacteria potentially resistant to tetracyclines and sulphonamides. The presence of these ARGs was independent of the total bacterial density and temperature. The dynamics of tet(A) and sulII genes were, however, positively correlated with dissolved oxygen and negatively to chlorophyll a, suggesting that the resistant microbes inhabit specific niches. These observations indicate that the lake is a reservoir of antibiotic resistances, highlighting the need of a deeper understanding of the sources of ARGs and the factors allowing their persistence in waters. 相似文献
94.
Aurelio Reyes Laura Melchionda Alessia Nasca Franco Carrara Eleonora Lamantea Alice Zanolini Costanza Lamperti Mingyan Fang Jianguo Zhang Dario Ronchi Sara Bonato Gigliola Fagiolari Maurizio Moggio Daniele Ghezzi Massimo Zeviani 《American journal of human genetics》2015,97(1):186-193
Chronic progressive external ophthalmoplegia (CPEO) is common in mitochondrial disorders and is frequently associated with multiple mtDNA deletions. The onset is typically in adulthood, and affected subjects can also present with general muscle weakness. The underlying genetic defects comprise autosomal-dominant or recessive mutations in several nuclear genes, most of which play a role in mtDNA replication. Next-generation sequencing led to the identification of compound-heterozygous RNASEH1 mutations in two singleton subjects and a homozygous mutation in four siblings. RNASEH1, encoding ribonuclease H1 (RNase H1), is an endonuclease that is present in both the nucleus and mitochondria and digests the RNA component of RNA-DNA hybrids. Unlike mitochondria, the nucleus harbors a second ribonuclease (RNase H2). All affected individuals first presented with CPEO and exercise intolerance in their twenties, and these were followed by muscle weakness, dysphagia, and spino-cerebellar signs with impaired gait coordination, dysmetria, and dysarthria. Ragged-red and cytochrome c oxidase (COX)-negative fibers, together with impaired activity of various mitochondrial respiratory chain complexes, were observed in muscle biopsies of affected subjects. Western blot analysis showed the virtual absence of RNase H1 in total lysate from mutant fibroblasts. By an in vitro assay, we demonstrated that altered RNase H1 has a reduced capability to remove the RNA from RNA-DNA hybrids, confirming their pathogenic role. Given that an increasing amount of evidence indicates the presence of RNA primers during mtDNA replication, this result might also explain the accumulation of mtDNA deletions and underscores the importance of RNase H1 for mtDNA maintenance. 相似文献
95.
Giovanni Bacci Maria Teresa Ceccherini Alessia Bani Marco Bazzicalupo Maurizio Castaldini Marco Galardini Luciana Giovannetti Stefano Mocali Roberta Pastorelli Ottorino Luca Pantani Paola Arfaioli Giacomo Pietramellara Carlo Viti Paolo Nannipieri Alessio Mengoni 《Antonie van Leeuwenhoek》2015,107(3):785-797
96.
Polyana C Tizioto Jeremy F Taylor Jared E Decker Caio F Gromboni Mauricio A Mudadu Robert D Schnabel Luiz L Coutinho Gerson B Mour?o Priscila SN Oliveira Marcela M Souza James M Reecy Renata T Nassu Flavia A Bressani Patricia Tholon Tad S Sonstegard Mauricio M Alencar Rymer R Tullio Ana RA Nogueira Luciana CA Regitano 《遗传、选种与进化》2015,47(1)
97.
98.
99.
Riccio A Mangiapia G Giordano D Flagiello A Tedesco R Bruno S Vergara A Mazzarella L di Prisco G Pucci P Paduano L Verde C 《IUBMB life》2011,63(5):346-354
In vitro, and possibly in vivo, hemoglobin polymerization and red blood cell sickling appear to be widespread in codfish. In this article, we show that the hemoglobins of the two Arctic fish Lycodes reticulatus and Gadus morhua also have the tendency to polymerize, as monitored by dynamic light scattering experiments. The elucidation of the primary structure of the single hemoglobin of the zoarcid L. reticulatus shows the presence of a large number of cysteyl residues in α and β chains. Their role in eliciting the ability to produce polymers was also addressed by MALDI-TOF and TOF-TOF mass spectrometry. The G.morhua globins are also rich in Cys, but unlike in L. reticulatus, polymerization does not seem to be disulfide driven. The widespread occurrence of the polymerization phenomenon displayed by hemoglobins of Arctic fish supports the hypothesis that this feature may bea response to stressful environmental conditions. 相似文献
100.
Wiederkehr A Szanda G Akhmedov D Mataki C Heizmann CW Schoonjans K Pozzan T Spät A Wollheim CB 《Cell metabolism》2011,13(5):601-611
Mitochondrial Ca(2+) signals have been proposed to accelerate oxidative metabolism and ATP production to match Ca(2+)-activated energy-consuming processes. Efforts to understand the signaling role of mitochondrial Ca(2+) have been hampered by the inability to manipulate matrix Ca(2+) without directly altering cytosolic Ca(2+). We were able to selectively buffer mitochondrial Ca(2+) rises by targeting the Ca(2+)-binding protein S100G to the matrix. We find that matrix Ca(2+) controls signal-dependent NAD(P)H formation, respiration, and ATP changes in intact cells. Furthermore, we demonstrate that matrix Ca(2+) increases are necessary for the amplification of sustained glucose-dependent insulin secretion in β cells. Through the regulation of NAD(P)H in adrenal glomerulosa cells, matrix Ca(2+) also acts as a positive signal in reductive biosynthesis, which stimulates aldosterone secretion. Our dissection of cytosolic and mitochondrial Ca(2+) signals reveals the physiological importance of matrix Ca(2+) in energy metabolism required for signal-dependent hormone secretion. 相似文献