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Dobránszki Judit Hidvégi Norbert Gulyás Andrea Teixeira da Silva Jaime A. 《Plant molecular biology》2019,100(4-5):511-525
Plant Molecular Biology - In response to an ultrasound pulse, several hundred DEGs, including in response to stress, were up- or down-regulated in in vitro potato plantlets. Despite this abiotic... 相似文献
116.
Michelle P. Clark Thao Huynh Shringar Rao Liana Mackiewicz Hugh Mason Shahla Romal Michael D. Stutz Sang H. Ahn Linda Earnest Vitina Sozzi Margaret Littlejohn Bang M. Tran Norbert Wiedemann Elizabeth Vincan Joseph Torresi Hans J. Netter Tokameh Mahmoudi Peter Revill Marc Pellegrini Gregor Ebert 《Cell death & disease》2021,12(7)
A major unmet clinical need is a therapeutic capable of removing hepatitis B virus (HBV) genome from the liver of infected individuals to reduce their risk of developing liver cancer. A strategy to deliver such a therapy could utilize the ability to target and promote apoptosis of infected hepatocytes. Presently there is no clinically relevant strategy that has been shown to effectively remove persistent episomal covalently closed circular HBV DNA (cccDNA) from the nucleus of hepatocytes. We used linearized single genome length HBV DNA of various genotypes to establish a cccDNA-like reservoir in immunocompetent mice and showed that clinical-stage orally administered drugs that antagonize the function of cellular inhibitor of apoptosis proteins can eliminate HBV replication and episomal HBV genome in the liver. Primary human liver organoid models were used to confirm the clinical relevance of these results. This study underscores a clinically tenable strategy for the potential elimination of chronic HBV reservoirs in patients.Subject terms: Target validation, Hepatitis B, Preclinical research, Translational research 相似文献
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Plasmonics - We present a plasmonic bandpass filter and refractive index sensor based on perturbed square cavity resonator with slits, which is fed by orthogonally oriented feeding waveguides. The... 相似文献
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Pey R Bach J Schieren G Gretz N Hafner M 《In vitro cellular & developmental biology. Animal》1999,35(10):571-579
Summary Autosomal dominant polycystic kidney disease (ADPKD) is one of the most frequent human inherited diseases. The main feature
of the disease is the development of renal cysts, first occurring in the proximal tubules, and with time, dominating all segments
of the nephron, leading to end-stage renal disease in 50% of the patients in their fifth decade of life. A therapy for polycystic
kidney disease (PKD) has not yet been developed. Patients coming to end-stage ADPKD require long-term dialysis and/or transplantation.
A suitable animal model to study ADPKD is the spontaneously mutated Han:SPRD (cy/ +) rat, but a method to cultivate Han:SPRD (cy/ +) derived renal cells which preserves their ability to form cyst-like structures in vitro has previously not been reported.
Based on this well-characterized animal model, we developed a cell culture model of renal cyst formation in vitro. When renal
cells of the Han:SPRD (cy/ +) rat were isolated and cultured under conditions that prevent cell-substratum adhesion, large amounts of cyst-like structures
were formed de novo from Han:SPRD (cy/ +) derived renal cells, but only a few from control rat renal cells. In contrast, when cultivated on plastic as monolayer
cultures, Han:SPRD (cy/ +)-derived and control rat-derived renal cells were indistinguishable and did not form cyst-like structures. Immunohistochemical
characterization of the cyst-like structures suggests tubular epithelial origin of the cyst-forming cells. The amount of cysts
formed from Han:SPRD (cy/ +)-derived renal cells grown in a stationary suspension culture is susceptible to modulation by different conditions. Human
cyst fluid and epidermal growth factor both stimulated the formation of cysts from Han:SPRD (cy/ +)-derived renal cells whereas taxol inhibited cystogenesis. In contrast, neither human cyst fluid nor epidermal growth
factor affected the amount of cysts formed by control rat renal cells. As the culture model reported here allows not only
the distinction of PKD-derived tubular epithelium from its normal counterpart, but also the modulation of cyst formation especially
by Han:SPRD (cy/ +)-derived renal cells, it might be a useful prescreening protocol for potential treatments for PKD and thus reduce the
need for animal experiments.
Both authors contributed equally to the work. 相似文献
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A CD8+ T cell of naive phenotype has multiple career choices during its primary differentiation into an effector cell population. One of these career options is becoming a CD8low T cell. We have previously shown by in vitro studies that CD8low T cells have lost expression of CD8 surface protein and mRNA and are poorly cytolytic. In line with poor cytolytic function, CD8low T cells express low levels of perforin and granzyme B and C, mediators of the granule-exocytosis machinery. However, CD8low T cells express IFN-gamma and substantial amounts of IL-4, the signature cytokines of type 1 and type 2 T-cell polarization, respectively. Here, we argue that the CD8low phenotype is an alternative career choice for any naive CD8+ T cell during primary activation but that the probability of choosing this option is greatly enhanced by both IL-4 and strong activation conditions. CD8low T cells have downregulated CD8 alpha/beta heterodimers and no preferential CD8 alpha/alpha homodimer expression. As shown by anti-CD8 Ab blocking experiments, surface CD8 substantially contributes to the CD8 T cell's effector function (i.e. cytokine expression and cytolytic activity). The distinct effector profile of CD8low T cells gives an example of the complexity of different CD8 T cell careers during primary effector differentiation. 相似文献
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L-Homocysteine and L-homocystine stereospecifically induce endothelial nitric oxide synthase-dependent lipid peroxidation in endothelial cells 总被引:8,自引:0,他引:8
Heydrick SJ Weiss N Thomas SR Cap AP Pimentel DR Loscalzo J Keaney JF 《Free radical biology & medicine》2004,36(5):632-640
Atherothrombotic cardiovascular disease associated with hyperhomocysteinemia has been proposed to result, at least in part, from increased vascular oxidative stress. Here we characterize one mechanism by which homocyteine may induce a vascular cell type-specific oxidative stress. Our results show that L-homocysteine at micromolar levels stereospecifically increases lipid peroxidation in cultured endothelial cells, but not in vascular smooth muscle cells or when medium is incubated in the absence of cells. Consistent with these observations, homocysteine also increases the formation of intracellular reactive oxygen species. The pro-oxidant effect of homocysteine can be fully replicated by an equivalent concentration of homocystine (i.e., an oxidized form of homocysteine), but not with cysteine or glutathione. Homocyst(e)ine-dependent lipid peroxidation is independent of H(2)O(2) and alterations in glutathione peroxidase activity, but dependent on superoxide. Mechanistically, the pro-oxidant effect of homocysteine appears to involve endothelial nitric oxide synthase (eNOS), as it is blocked by the eNOS inhibitor L-N(G)-nitroarginine methyl ester. Thus, homocyst(e)ine actively promotes oxidative stress in endothelial cells via an eNOS-dependent mechanism. 相似文献