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1.
Means to increase the reproductive capacity of Crocus sativus L., in vitro, are described. Cytokinins and auxin were found to be essential for development of bud explants. Ethylene and ethaphon pretreatments inhibited leaf development but induced corm production. Microsurgery of the apical bud combined with ethylene pretreatment increased both sprouting and corm production. 相似文献
2.
Ziv Radisavljevic 《Journal of cellular biochemistry》2019,120(8):12123-12127
Hyperactivated lysosome causes cancer and induces metastasis or cancer relapse. Such activation occurs during excessive, intense, and protracted oxidative burst in the lysosome. The burst induces the formation of the constitutively active (permanently active) AKT locus generating cancer complexity and robustness. Such condition has the tendency to persist by stabilized intense signaling inducing upregulation of cell function and metabolic setup at the higher level. Most intense activator of the lysosome is the fungus Aspergillus fumigatus, which activates the AKT, a critical element in lysosome control, inducing cancer development, metastatic progression, or cancer relapse. Targeting the AKT active site of hydrogen network, by redox balance change or hydrogen balance change or muon-catalyzed fusion or laser-induced fusion with anti- A. fumigatus medication converts active AKT locus into inactive element, inducing disappearance of malignant phenotype. 相似文献
3.
4.
Ziv M. Machnes Tony C. T. Huang Philip K. Y. Chang Raminder Gill Nicholas Reist Gabriella Dezsi Ezgi Ozturk Francois Charron Terence J. O’Brien Nigel C. Jones R. Anne McKinney Moshe Szyf 《PloS one》2013,8(10)
Epilepsy is a chronic brain disorder involving recurring seizures often precipitated by an earlier neuronal insult. The mechanisms that link the transient neuronal insult to the lasting state of epilepsy are unknown. Here we tested the possible role of DNA methylation in mediating long-term induction of epileptiform activity by transient kainic acid exposure using in vitro and in vivo rodent models. We analyzed changes in the gria2 gene, which encodes for the GluA2 subunit of the ionotropic glutamate, alpha-amino-3-hydroxy-5-methyl-4-isoxazole proprionic acid receptor and is well documented to play a role in epilepsy. We show that kainic acid exposure for two hours to mouse hippocampal slices triggers methylation of a 5’ regulatory region of the gria2 gene. Increase in methylation persists one week after removal of the drug, with concurrent suppression of gria2 mRNA expression levels. The degree of kainic acid-induced hypermethylation of gria2 5’ region varies between individual slices and correlates with the changes in excitability induced by kainic acid. In a rat in vivo model of post kainic acid-induced epilepsy, we show similar hypermethylation of the 5’ region of gria2. Inter-individual variations in gria2 methylation, correlate with the frequency and intensity of seizures among epileptic rats. Luciferase reporter assays support a regulatory role for methylation of gria2 5’ region. Inhibition of DNA methylation by RG108 blocked kainic acid-induced hypermethylation of gria2 5’ region in hippocampal slice cultures and bursting activity. Our results suggest that DNA methylation of such genes as gria2 mediates persistent epileptiform activity and inter-individual differences in the epileptic response to neuronal insult and that pharmacological agents that block DNA methylation inhibit epileptiform activity raising the prospect of DNA methylation inhibitors in epilepsy therapeutics. 相似文献
5.
A cancer microenvironment generates strong hydrogen bond network system by the positive feedback loops supporting cancer complexity and robustness. Such network functions through the AKT locus generating high entropic energy supporting cancer metastatic robustness. Charged lepton particle muon follows the rule of Bragg effect during a collision with hydrogen network in cancer cells. Muon beam dismantles hydrogen bond network in cancer by the muon-catalyzed fusion, leading to apoptosis of cancer cells. Muon induces cumulative energy appearance on the hydrogen bond network in a cancer cell with its fast decay to an electron and two neutrinos. Thus, muon beam, muonic atom, muon neutrino shower, and electrons simultaneously cause fast neutralization of the AKT hydrogen bond network by the conversion of hydrogen into deuterium or helium, inactivating the hydrogen bond networks and inducing failure of cancer complexity and robustness with the disappearance of a malignant phenotype. 相似文献
6.
Meira Ziv 《In vitro cellular & developmental biology. Plant》1991,27(2):64-69
Summary Vitrification-Hyperhydrous shoot development, effects the survival and quality of several micropropagated plants ex-vitro.
The leaves which are the immediate organ to be affected, exhibit abnormal morphology and physiology. Leaf malfunction is apparently
a stress response to very rich media and high relative humidity. The understanding of the underlying mechanism of vitrification
and its control in vitro can contribute to a more efficient micropropagation. Vitrification was found to be associated with
elevated ethylene production which was related to hypolignification and poor cell wall development. Liquid and low agar media
induced callose formation along with reduced and disoriented cellulose biosynthesis, manifested also in non-functioning guard
cells. Malfunctioning stomata, in addition to defective cuticle contributed to increased transpiration and desiccation of
in vitro formed leaves. The activity of various enzymes, associated with cell wall synthesis, was low and total proteins in
normal leaves was higher than in vitreous ones. Various measures were found to reduce vitrification; lowered matrix and water
potential in the medium, reduction in RH, low NH
4
+
, changes in Ca++ levels and the removal of ethylene. These measures improved leaf morphogenesis, survival and the quality of several micropropagated
plant species.
Presented in the Session-in-Depth Transition of Plants From Culture to Establishment In Vivo,“ at the 41st Annual Meeting
of the Tissue Culture Association, Houston, Texas, June 10–13, 1990. 相似文献
7.
Marta Castro Lizet Sánchez Dennis Pérez Carlos Sebrango Ziv Shkedy Patrick Van der Stuyft 《PloS one》2013,8(12)
The reemergence of dengue as an important public health problem reflects the difficulties in sustaining vertically organized, effective, control programs and the need for community-based strategies for Aedes aegypti control that result in behavioral change. We aimed to disentangle the relationships between underlying determinants of dengue related practices. We conducted a cross-sectional study in 780 households in La Lisa, Havana, Cuba. A questionnaire and an observation guide were administrated to collect information on variables related to economic status, knowledge on dengue, risk perception and practices associated with Aedes aegypti breading sites. To test a conceptual model that hypothesized direct relationships among all these constructs, we first used Exploratory Factor Analysis with Principal Component Analysis to establish the relationship between observed variables and the underlying latent variables. Subsequently, we tested whether the observed data supported the conceptual model through Confirmatory Factor Analysis. Exploratory Factor Analysis indicated that the items measured could be reduced into five factors with an eigenvalue >1.0: Knowledge on dengue, Intradomiciliar risk practices, Peridomiciliar risk practices, Risk perception and Economic status. The proportion of the total variance in the data explained by these five factors was 74.3%. The Confirmatory Factor Analysis model differed from our hypothesized conceptual model. Only Knowledge on dengue had a significant, direct, positive, effect on Practices. There was also a direct association of Economic status with Knowledge on dengue, but not with Risk perception and Practices. Clarifying the relationship between direct and indirect determinants of dengue related practices contributes to a better understanding of the potential effect of Information Education and Communication on practices and on the reduction of Aedes aegypti breeding sites and provides inputs for designing a community based strategy for dengue control. 相似文献
8.
Ziv Radisavljevic 《Journal of cellular physiology》2013,228(1):21-24
Angiogenesis get full robustness in metastatic cancer, relapsed leukemia or lymphoma when complex positive feedback loop signaling systems become integrative. A cancer hypoxic microenvironment generates positive loops inducing formation of the vascular functional shunts. AKT is an upstream angiogenic locus of integrative robustness and fragility activated by the positive loops. AKT controls two downstream nodes the mTOR and NOS in nodal organization of the signaling genes. AKT phosphorylation is regulated by a balance of an oxidant/antioxidant. Targeting AKT locus represents new principle to control integrative angiogenic robustness by the locus chemotherapy. J. Cell. Physiol. 228: 21–24, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
9.
Serenella Sukno Orit Shimerling Jamie McCuiston Galit Tsabary Ziv Shani Oded Shoseyov Eric L Davis 《Journal of nematology》2006,38(3):354-361
The root-knot nematode Meloidogyne incognita is an obligate endoparasite of plant roots and stimulates elaborate modifications of selected root vascular cells to form giant cells for feeding. An Arabidopsis thaliana endoglucanase (Atcel1) promoter is activated in giant cells that were formed in Atcel1::UidA transgenic tobacco and Arabidopsis plants. Activity of the full-length Atcel1 promoter was detected in root and shoot elongation zones and in the lateral root primordia. Different 5’ and internal deletions of regions of the 1,673 bp Atcel1 promoter were each fused to the UidA reporter gene and transformed in tobacco, and roots of the transformants were inoculated with M. incognita to assay for GUS expression in giant cells and noninfected plant tissues. Comparison of the Atcel1 promoter deletion constructs showed that the region between −1,673 and −1,171 (fragment 1) was essential for Atcel1 promoter activity in giant cells and roots. Fragment 1 alone, however, was not sufficient for Atcel1 expression in giant cells or roots, suggesting that cis-acting elements in fragment 1 may function in consort with other elements within the Atcel1 promoter. Root-knot nematodes and giant cells developed normally within roots of Arabidopsis that expressed a functional antisense construct to Atcel1, suggesting that a functional redundancy in endoglucanase activity may represent another level of regulatory control of cell wall-modifying activity within nematode feeding cells. 相似文献
10.