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101.
Izabela A. Rodenhuis-Zybert Hilde M. van der Schaar Júlia M. da Silva Voorham Heidi van der Ende-Metselaar Huan-Yao Lei Jan Wilschut Jolanda M. Smit 《PLoS pathogens》2010,6(1)
Cells infected with dengue virus release a high proportion of immature prM-containing virions. In accordance, substantial levels of prM antibodies are found in sera of infected humans. Furthermore, it has been recently described that the rates of prM antibody responses are significantly higher in patients with secondary infection compared to those with primary infection. This suggests that immature dengue virus may play a role in disease pathogenesis. Interestingly, however, numerous functional studies have revealed that immature particles lack the ability to infect cells. In this report, we show that fully immature dengue particles become highly infectious upon interaction with prM antibodies. We demonstrate that prM antibodies facilitate efficient binding and cell entry of immature particles into Fc-receptor-expressing cells. In addition, enzymatic activity of furin is critical to render the internalized immature virus infectious. Together, these data suggest that during a secondary infection or primary infection of infants born to dengue-immune mothers, immature particles have the potential to be highly infectious and hence may contribute to the development of severe disease. 相似文献
102.
Background
Post traumatic stress disorder (PTSD) can be considered the result of a failure to recover after a traumatic experience. Here we studied possible protective and therapeutic aspects of environmental enrichment (with and without a running wheel) in Sprague Dawley rats exposed to an inescapable foot shock procedure (IFS).Methodology/Principal Findings
IFS induced long-lasting contextual and non-contextual anxiety, modeling some aspects of PTSD. Even 10 weeks after IFS the rats showed reduced locomotion in an open field. The antidepressants imipramine and escitalopram did not improve anxiogenic behavior following IFS. Also the histone deacetylase (HDAC) inhibitor sodium butyrate did not alleviate the IFS induced immobility. While environmental enrichment (EE) starting two weeks before IFS did not protect the animals from the behavioral effects of the shocks, exposure to EE either immediately after the shock or one week later induced complete recovery three weeks after IFS. In the next set of experiments a running wheel was added to the EE to enable voluntary exercise (EE/VE). This also led to reduced anxiety. Importantly, this behavioral recovery was not due to a loss of memory for the traumatic experience. The behavioral recovery correlated with an increase in cell proliferation in hippocampus, a decrease in the tissue levels of noradrenalin and increased turnover of 5-HT in prefrontal cortex and hippocampus.Conclusions/Significance
This animal study shows the importance of (physical) exercise in the treatment of psychiatric diseases, including post-traumatic stress disorder and points out the possible role of EE in studying the mechanism of recovery from anxiety disorders. 相似文献103.
Vipan Kumar Parihar K.R. Prabhakar Veeresh P. Veerapur M. Sudheer Kumar Y. Rosi Reddy Ravi Joshi M.K. Unnikrishnan C. Mallikarjuna Rao 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2006,611(1-2):9-16
The radio-protective ability of sesamol (SM) at various doses viz., 0, 10, 25, 40, 50, 70 and 100 mg/kg bw, administered intraperitoneally 30 min prior to 9.5 Gy whole-body γ-irradiation was studied in Swiss albino mice. Radiation toxicity and mortality were observed during a period of 30 days and the percentage mortality was calculated. SM pretreatment with 50 mg/kg bw was found to be the most effective dose in maintaining body weight and in reducing the percentage mortality, while 100 mg/kg bw was found to be more effective in maintaining the spleen index and in stimulation of endogenous spleen colony-forming units. Pretreatment with SM (50 mg/kg bw) in mice irradiated with 15 Gy significantly reduced dead, inflammatory, mitotic and goblet cells in irradiated jejunum. SM at 50 mg/kg bw also increased crypt cells, maintained villus height, and prevented mucosal erosion. Nuclear enlargement in epithelial cells was found less in SM-treated mice compared with the irradiated control. The radiation-induced decrease in endogenous antioxidant enzymes (GSH, GST, catalase) and the increase in lipid peroxidation were also reduced by pretreatment with SM [50 and 100 mg/kg bw] at all monitored post-irradiation intervals. There was no protection at a dose less than 25 mg/kg bw. 相似文献
104.
de Poorter JJ Lipinski KS Nelissen RG Huizinga TW Hoeben RC 《The journal of gene medicine》2007,9(8):639-648
BACKGROUND: Predictable and adequate transgene expression is essential for clinical gene therapy. Several studies have focused on optimization of transgene expression. In this study the effect of sodium butyrate (NaB) and a ubiquitous chromatin opening element (UCOE) on short-term gene expression after adenovirus-mediated gene transfer in fibroblastic interface cells from periprosthetic tissue in loosened orthopedic implants is investigated. METHODS: Cultures of diploid human interface cells from four patients were infected with an adenovirus type-5 vector that carries the luciferase gene driven by the cytomegalovirus (CMV) promoter as a reporter. In addition, viruses with a UCOE were evaluated. Twenty-four hours after infection NaB was added in concentrations of 0 to 9 mM. Luciferase activity was tested after a further 24 h. RESULTS: NaB in a concentration of 6 mM caused a 7- to 16-fold increase in reporter gene expression compared to control condition. There was no difference in reporter gene expression when cells were infected with Ad.1.5UCOE-CMV.Luc compared to Ad.CMV.Luc. A combination of NaB and a UCOE had no advantage over NaB alone. CONCLUSIONS: Addition of NaB results in a marked increase in transgene expression in cultured cells. This would allow the enhancement of the expression of the transgene, without requiring a higher vector dose. Butyrate administration could not be substituted by inclusion of UCOEs in the vector. It remains to be established whether the effective concentrations of butyrate can be obtained in vivo. 相似文献
105.
106.
Aghaei A. Bochud N. Rosi G. Naili S. 《Biomechanics and modeling in mechanobiology》2021,20(2):433-448
Biomechanics and Modeling in Mechanobiology - The interphase joining tendon to bone plays the crucial role of integrating soft to hard tissues, by effectively transferring stresses across two... 相似文献
107.
Leopold Parts Amandine Batt Maykel Lopes Michael W Yuen Meredith Laver BryanJoseph San Luis JiaXing Yue Carles Pons Elise Eray Patrick Aloy Gianni Liti Jolanda van Leeuwen 《Molecular systems biology》2021,17(5)
The consequence of a mutation can be influenced by the context in which it operates. For example, loss of gene function may be tolerated in one genetic background, and lethal in another. The extent to which mutant phenotypes are malleable, the architecture of modifiers and the identities of causal genes remain largely unknown. Here, we measure the fitness effects of ~ 1,100 temperature‐sensitive alleles of yeast essential genes in the context of variation from ten different natural genetic backgrounds and map the modifiers for 19 combinations. Altogether, fitness defects for 149 of the 580 tested genes (26%) could be suppressed by genetic variation in at least one yeast strain. Suppression was generally driven by gain‐of‐function of a single, strong modifier gene, and involved both genes encoding complex or pathway partners suppressing specific temperature‐sensitive alleles, as well as general modifiers altering the effect of many alleles. The emerging frequency of suppression and range of possible mechanisms suggest that a substantial fraction of monogenic diseases could be managed by modulating other gene products. 相似文献
108.
Gerty Schreibelt Jurjen Tel Kwinten H. E. W. J. Sliepen Daniel Benitez-Ribas Carl G. Figdor Gosse J. Adema I. Jolanda M. de Vries 《Cancer immunology, immunotherapy : CII》2010,59(10):1573-1582
Dendritic cells (DCs) are central players of the immune response. To date, DC-based immunotherapy is explored worldwide in
clinical vaccination trials with cancer patients, predominantly with ex vivo-cultured monocyte-derived DCs (moDCs). However,
the extensive culture period and compounds required to differentiate them into DCs may negatively affect their immunological
potential. Therefore, it is attractive to consider alternative DC sources, such as blood DCs. Two major types of naturally
occurring DCs circulate in peripheral blood, myeloid DCs (mDCs) and plasmacytoid (pDCs). These DC subsets express different
surface molecules and are suggested to have distinct functions. Besides scavenging pathogens and presenting antigens, DCs
secrete cytokines, all of which is vital for both the acquired and the innate immune system. These immunological functions
relate to Toll-like receptors (TLRs) expressed by DCs. TLRs recognize pathogen-derived products and subsequently provoke DC
maturation, antigen presentation and cytokine secretion. However, not every TLR is expressed on each DC subset nor causes
the same effects when activated. Considering the large amount of clinical trials using DC-based immunotherapy for cancer patients
and the decisive role of TLRs in DC maturation, this review summarizes TLR expression in different DC subsets in relation
to their function. Emphasis will be given to the therapeutic potential of TLR-matured DC subsets for DC-based immunotherapy. 相似文献
109.
This special issue aims to contribute to the conceptualization of World Art Studies. The first two articles offer evaluative
views from art history, the third and fourth perspectives from anthropology, the fifth and sixth arguments for including neo-evolutionary
and neurological studies in understanding world art as a universal human behavior. 相似文献
110.