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31.
Didem Turgut Coşan Faruk Saydam Cansu Özbayer Fulya Doğaner Ahu Soyocak Hasan Veysi Güneş İrfan Değirmenci Hülyam Kurt Mehmet Cengiz Üstüner Cengiz Bal 《Cytotechnology》2015,67(1):97-105
Hypertension is a major health problem with increasing prevalence around the world. Tannic acid is water-soluble polyphenol that is present in tea, green tea, coffee, red wine, nuts, fruits and many plant foods. It has been reported to serve as an antioxidant or a pro-oxidant depending on the type of cells and its concentration. The purpose of our study was to evaluate the effect of tannic acid on systolic blood pressure, oxidative stress and some urinary parameters in the rat model of essential hypertension. Blood pressures of all rats were measured using the tail-cuff method. The nitric oxide synthase inhibitor N (omega)-nitro-L-arginine was administered orally at a dose of 0.5 g/l/day for 15 days to rats in order to create an animal model of hypertension. Tannic acid was intraperitoneally injected at a dose of 50 mg/kg for 15 days. Superoxide dismutase, catalase activity and the concentration of malondialdehyde (MDA) were determined in blood plasma and homogenates of heart, liver and kidney. In order to evaluate renal functions, urine pH, urine volume, urine creatine, uric acid, and urea nitrogen values were measured. Compared with the hypertension group, a decrease in MDA concentrations of heart tissue (p < 0.01), urea nitrogen values (p < 0.01) and urine volumes (p < 0.001) were established in hypertension + tannic acid group. There was also a decrease in blood pressure values (20th and 30th days) of this group, but there was no a statistical difference according to hypertension group. The findings of our research show the effect of tannic acid in lowering blood pressure in hypertensive rats. 相似文献
32.
Wendy J. van Zuylen Priscilla Doyon Jean-Fran?ois Clément Kashif Aziz Khan Lisa M. D'Ambrosio Florence D? Myriam St-Amant-Verret Tasheen Wissanji Gregory Emery Anne-Claude Gingras Sylvain Meloche Marc J. Servant 《PLoS pathogens》2012,8(7)
Tumor Necrosis Factor receptor-associated factor-3 (TRAF3) is a central mediator important for inducing type I interferon (IFN) production in response to intracellular double-stranded RNA (dsRNA). Here, we report the identification of Sec16A and p115, two proteins of the ER-to-Golgi vesicular transport system, as novel components of the TRAF3 interactome network. Notably, in non-infected cells, TRAF3 was found associated with markers of the ER-Exit-Sites (ERES), ER-to-Golgi intermediate compartment (ERGIC) and the cis-Golgi apparatus. Upon dsRNA and dsDNA sensing however, the Golgi apparatus fragmented into cytoplasmic punctated structures containing TRAF3 allowing its colocalization and interaction with Mitochondrial AntiViral Signaling (MAVS), the essential mitochondria-bound RIG-I-like Helicase (RLH) adaptor. In contrast, retention of TRAF3 at the ER-to-Golgi vesicular transport system blunted the ability of TRAF3 to interact with MAVS upon viral infection and consequently decreased type I IFN response. Moreover, depletion of Sec16A and p115 led to a drastic disorganization of the Golgi paralleled by the relocalization of TRAF3, which under these conditions was unable to associate with MAVS. Consequently, upon dsRNA and dsDNA sensing, ablation of Sec16A and p115 was found to inhibit IRF3 activation and anti-viral gene expression. Reciprocally, mild overexpression of Sec16A or p115 in Hec1B cells increased the activation of IFNβ, ISG56 and NF-κB -dependent promoters following viral infection and ectopic expression of MAVS and Tank-binding kinase-1 (TBK1). In line with these results, TRAF3 was found enriched in immunocomplexes composed of p115, Sec16A and TBK1 upon infection. Hence, we propose a model where dsDNA and dsRNA sensing induces the formation of membrane-bound compartments originating from the Golgi, which mediate the dynamic association of TRAF3 with MAVS leading to an optimal induction of innate immune responses. 相似文献
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Hélène Malka-Mahieu Isabelle Girault Margot Rubington Melissa Leriche Caroline Welsch Nyam Kamsu-Kom 《Cell cycle (Georgetown, Tex.)》2016,15(18):2405-2409
Activating mutations of the NRAS (neuroblastoma rat sarcoma viral oncogene) protein kinase, present in many cancers, induce a constitutive activation of both the RAS-RAF-MEK-ERK mitogen-activated protein kinase (MAPK) signal transduction pathway and the PI(3)K-AKT-mTOR, pathway. This in turn regulates the formation of the eIF4F eukaryotic translation initiation complex, comprising the eIF4E cap-binding protein, the eIF4G scaffolding protein and the eIF4A RNA helicase, which binds to the 7-methylguanylate cap (m(7)G) at the 5′ end of messenger RNAs. Small molecules targeting MEK (MEKi: MEK inhibitors) have demonstrated activity in NRAS-mutant cell lines and tumors, but resistance sets in most cases within months of treatment. Using proximity ligation assays, that allows visualization of the binding of eIF4E to the scaffold protein eIF4G, generating the active eIF4F complex, we have found that resistance to MEKi is associated with the persistent formation of the eIF4F complex in MEKi-treated NRAS-mutant cell lines. Furthermore, inhibiting the eIF4A component of the eIF4F complex, with a small molecule of the flavagline/rocaglate family, synergizes with inhibiting MEK to kill NRAS-mutant cancer cell lines. 相似文献
35.
Christian G. Blumentrath Martin P. Grobusch Pierre-Blaise Matsiégui Friedrich Pahlke Rella Zoleko-Manego Solange Nzenze-Aféne Barthélemy Mabicka Maurizio Sanguinetti Peter G. Kremsner Frieder Schaumburg 《PLoS neglected tropical diseases》2015,9(10)
Background
Rhinoentomophthoromycosis, or rhino-facial conidiobolomycosis, is a rare, grossly disfiguring disease due to an infection with entomophthoralean fungi. We report a case of rhinoentomophthoromycosis from Gabon and suggest a staging system, which provides information on the prognosis and duration of antifungal therapy.Methods
We present a case of rhinoentomophthoromycosis including the histopathology, mycology, and course of disease. For the suggested staging system, all cases on confirmed rhinoentomophthoromycosis published in the literature without language restriction were eligible. Exclusion criteria were missing data on (i) duration of disease before correct diagnosis, (ii) outcome, and (iii) confirmation of entomophthoralean fungus infection by histopathology and/or mycology. We classified cases into atypical (orbital cellulitis, severe pain, fever, dissemination), early, intermediate, and late disease based on the duration of symptoms before diagnosis. The outcome was evaluated for each stage of disease.Findings
The literature search of the Medpilot database was conducted on January 13, 2014, (updated on January 18, 2015). The search yielded 8,333 results including 198 cases from 117 papers; of these, 145 met our inclusion criteria and were included in the final analysis. Median duration of treatment was 4, 3, 4, and 5 months in atypical, early, intermediate, and late disease, respectively. Cure rates were clearly associated with stage of disease and were 57%, 100%, 82%, and 43% in atypical, early, intermediate, and late disease, respectively.Conclusion
We suggest a clinical staging system that underlines the benefit of early case detection and may guide the duration of antifungal treatment. The scientific value of this classification is its capacity to structure and harmonize the clinical and research approach towards rhinoentomophthoromycosis. 相似文献36.
In recent years, the diagnostic and therapeutic uses of radioisotopes have shown significant progress. Immunoglobulin (Ig) appears to be a promising tracer, particularly due to its ability to target selected antigens. The main objective of this study is to optimize and assess an Ig radiolabeling method with Technetium 99m (99mTc), an attractive radioelement used widely for diagnostic imaging. Monoclonal anti-CD20 IgG was retained to study in vitro and in vivo radiolabeling impact. After IgG derivatization with 2-iminothiolane, IgG-SH was radiolabeled by an indirect method, using a 99mTc-tricarbonyl core. Radiolabeling stability was evaluated over 24h by thin-layer chromatography. IgG integrity was checked by sodium dodecyl sulfate—polyacrylamide gel electrophoresis coupled with Western blot and autoradiography. The radiolabeled Ig’s immunoaffinity was assessed in vitro by a radioimmunoassay method and binding experiments with cells (EL4-hCD20 and EL4-WT). Biodistribution studies were performed in normal BALB/c mice. Tumor uptake was assessed in mice bearing EL4-hCD20 and EL4-WT subcutaneous xenografts. With optimized method, high radiolabeling yields were obtained (95.9 ± 3.5%). 99mTc-IgG-SH was stable in phosphate-buffered saline (4°C and 25°C) and in serum (37°C), even if important sensitivity to transchelation was observed. IgG was not degraded by derivatization and radiolabeling, as shown by Western blot and autoradiography results. 99mTc-anti-CD20 IgG-SH immunoaffinity was estimated with Kd = 35 nM by both methods. In vivo biodistribution studies for 48h showed significant accumulation of radioactivity in plasma, liver, spleen, lungs and kidneys. Planar scintigraphy of mice bearing tumors showed a significant uptake of 99mTc-anti-CD20 IgG-SH in CD20+ tumor versus CD20- tumor. Radiolabeling of derivatized IgG with 99mTc-tricarbonyl was effective, stable and required few antibody amounts. This attractive radiolabeling method is “antibody safe” and preserves Ig affinity for antigen, as shown by both in vitro and in vivo experiments. This method could easily be used with noncommercial IgG or other antibody isotypes. 相似文献
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Beno?t de Chassey Anne Aublin-Gex Alessia Ruggieri Laurène Meyniel-Schicklin Fabrine Pradezynski Nathalie Davoust Thibault Chantier Lionel Tafforeau Philippe-Emmanuel Mangeot Claire Ciancia Laure Perrin-Cocon Ralf Bartenschlager Patrice André Vincent Lotteau 《PLoS pathogens》2013,9(7)
Influenza A NS1 and NS2 proteins are encoded by the RNA segment 8 of the viral genome. NS1 is a multifunctional protein and a virulence factor while NS2 is involved in nuclear export of viral ribonucleoprotein complexes. A yeast two-hybrid screening strategy was used to identify host factors supporting NS1 and NS2 functions. More than 560 interactions between 79 cellular proteins and NS1 and NS2 proteins from 9 different influenza virus strains have been identified. These interacting proteins are potentially involved in each step of the infectious process and their contribution to viral replication was tested by RNA interference. Validation of the relevance of these host cell proteins for the viral replication cycle revealed that 7 of the 79 NS1 and/or NS2-interacting proteins positively or negatively controlled virus replication. One of the main factors targeted by NS1 of all virus strains was double-stranded RNA binding domain protein family. In particular, adenosine deaminase acting on RNA 1 (ADAR1) appeared as a pro-viral host factor whose expression is necessary for optimal viral protein synthesis and replication. Surprisingly, ADAR1 also appeared as a pro-viral host factor for dengue virus replication and directly interacted with the viral NS3 protein. ADAR1 editing activity was enhanced by both viruses through dengue virus NS3 and influenza virus NS1 proteins, suggesting a similar virus-host co-evolution. 相似文献
40.
Michaela Ecker Hervé Bocherens Marie-Anne Julien Florent Rivals Jean-Paul Raynal Marie-Hélène Moncel 《Journal of human evolution》2013
The Middle Palaeolithic site of Payre in southeastern France yields abundant archaeological material associated with fossil hominid remains. With its long sequence of Middle Pleistocene deposits, Payre is a key site to study the Middle Palaeolithic chronology of this region. This study is the first to investigate carbon and oxygen isotope contents of Neanderthal tooth enamel bioapatite, together with a wide range of herbivorous and carnivorous species. The aim is to contribute to the understanding of hunting behaviour, resource partitioning, diet and habitat use of animals and Neanderthals through a palaeoecological reconstruction. 相似文献