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11.
12.
Zamzam Awida Almog Bachar Hussam Saed Anton Gorodov Nathalie Ben-Califa Maria Ibrahim Albert Kolomansky Jennifer Ana Iden Liad Graniewitz Visacovsky Tamar Liron Sahar Hiram-Bab Michael Brines Yankel Gabet Drorit Neumann 《International journal of molecular sciences》2022,23(1)
The two erythropoietin (EPO) receptor forms mediate different cellular responses to erythropoietin. While hematopoiesis is mediated via the homodimeric EPO receptor (EPOR), tissue protection is conferred via a heteromer composed of EPOR and CD131. In the skeletal system, EPO stimulates osteoclast precursors and induces bone loss. However, the underlying molecular mechanisms are still elusive. Here, we evaluated the role of the heteromeric complex in bone metabolism in vivo and in vitro by using Cibinetide (CIB), a non-erythropoietic EPO analogue that exclusively binds the heteromeric receptor. CIB is administered either alone or in combination with EPO. One month of CIB treatment significantly increased the cortical (~5.8%) and trabecular (~5.2%) bone mineral density in C57BL/6J WT female mice. Similarly, administration of CIB for five consecutive days to female mice that concurrently received EPO on days one and four, reduced the number of osteoclast progenitors, defined by flow cytometry as Lin−CD11b−Ly6Chi CD115+, by 42.8% compared to treatment with EPO alone. In addition, CIB alone or in combination with EPO inhibited osteoclastogenesis in vitro. Our findings introduce CIB either as a stand-alone treatment, or in combination with EPO, as an appealing candidate for the treatment of the bone loss that accompanies EPO treatment. 相似文献
13.
Manana Kandashvili Georgi Gamkrelidze Lia Tsverava Tamar Lordkipanidze Eka Lepsveridze Vincenzo Lagani Maia Burjanadze Manana Dashniani Merab Kokaia Revaz Solomonia 《International journal of molecular sciences》2022,23(3)
Epilepsy is a severe neurological disease characterized by spontaneous recurrent seizures (SRS). A complex pathophysiological process referred to as epileptogenesis transforms a normal brain into an epileptic one. Prevention of epileptogenesis is a subject of intensive research. Currently, there are no clinically approved drugs that can act as preventive medication. Our previous studies have revealed highly promising antiepileptogenic properties of a compound–myo-inositol (MI) and the present research broadens previous results and demonstrates the long-term disease-modifying effect of this drug, as well as the amelioration of cognitive comorbidities. For the first time, we show that long-term treatment with MI: (i) decreases the frequency and duration of electrographic SRS in the hippocampus; (ii) has an ameliorating effect on spatial learning and memory deficit associated with epileptogenesis, and (iii) attenuates cell loss in the hippocampus. MI treatment also alters the expression of the glial fibrillary acidic protein, LRRC8A subunit of volume-regulated anion channels, and protein tyrosine phosphatase receptor type R, all expected to counteract the epileptogenesis. All these effects are still present even 4 weeks after MI treatment ceased. This suggests that MI may exert multiple actions on various epileptogenesis-associated changes in the brain and, therefore, could be considered as a candidate target for prevention of epileptogenesis. 相似文献
14.
Kuhn J Suissa M Chiswell D Azriel A Berman B Shahar D Reznick S Sharf R Wyse J Bar-On T Cohen I Giles R Weiser I Lubinsky-Mink S Ulitzur S 《International journal of food microbiology》2002,74(3):217-227
Felix 01 (F01) is a bacteriophage originally isolated by Felix and Callow which lyses almost all Salmonella strains and has been widely used as a diagnostic test for this genus. Molecular information about this phage is entirely lacking. In the present study, the DNA of the phage was found to be a double-stranded linear molecule of about 80 kb. 11.5 kb has been sequenced and in this region A + T content is 60%. There are relatively few restriction endonuclease cleavage sites in the native genome and clones show this is due to their absence rather than modification. A restriction map of the genome has been constructed. The ends of the molecule cannot be ligated although they contain 5' phosphates. At least 60% of the genome must encode proteins. In the sequenced portion, many open reading frames exist and these are tightly packed together. These have been examined for homology to published proteins but only 1 to 17 shows similarity to known proteins. F01 is therefore the prototype of a new phage family. On the basis of restriction sites, codon usage and the distribution of nonsense codons in the unused reading frames, a strong case can be made for natural selection that reacts to mRNA structure and function. 相似文献
15.
Although iron-based permeable reactive barriers are gaining importance for treating groundwater contaminants, little is currently known about the effect of cosolutes on barrier longevity. Because of their corrosion inhibiting properties, dissolved silica species are of particular concern. This research investigates the effect of silica on the reduction of 1,1,1-trichloroethane by granular iron as a function of added silica concentration, pH, and duration of iron exposure to dissolved silica. Batch studies reveal that, at pH 8.5 and above, added silica concentrations as low as 0.17 mM cause a 30% reduction in the reactivity of iron. At higher silica concentrations, reactivity decreases by 65-75%. The inhibitory effect is greater at higher pH: 0.83 mM silica has no apparent adverse effect at pH 7.5, but leads to a 46% decrease in reaction rate at pH 8 and 90% at pH 9. This corresponds to observed trends in silica adsorption onto iron, which is low at pH 7.3 but increases at higher pH. Extending the duration of iron exposure to silica solutions also leads to a more pronounced inhibitory effect. This is in good agreement with the increase in silica coverage on the iron surface as revealed by X-ray photoelectron spectroscopy. 相似文献
16.
Jeong-Mo Hong Tamar Shinar Myungjoo Kang Ronald Fedkiw 《Journal of scientific computing》2007,31(1-2):99-125
This review paper begins with an overview of the boundary condition capturing approach to solving problems with interfaces. Although the authors’ original motivation was to extend the ghost fluid method
from compressible to incompressible flow, the elliptic nature of incompressible flow quickly quenched the idea that ghost
cells could be defined and used in the usual manner. Instead the boundary conditions had to be implicitly captured by the
matrix formulation itself, leading to the novel approach. We first review the work on the variable coefficient Poisson equation,
noting that the simplicity of the method allowed for an elegant convergence proof. Simplicity and robustness also allowed
for a quick extension to three-dimensional two-phase incompressible flows including the effects of viscosity and surface tension,
which is discussed subsequently. The method has enjoyed popularity in both computational physics and computer graphics, and
we show some comparisons with the traditional delta function approach for the visual simulation of bubbles. Finally, we discuss
extensions to problems where the velocity is discontinuous as well, as is the case for premixed flames, and show an example
of multiple interacting liquids that includes all of the aforementioned phenomena. 相似文献
17.
Social learning in 11 human-raised capuchin monkeys (Cebus apella) was investigated using an artificial fruit that was designed as an analogue of natural foraging problems faced by primates. Each subject observed a human model open each of 3 principal components on the fruit in 1 of 2 alternative ways ("morphs"). The capuchin monkeys reproduced, to differing extents, the alternative techniques used for opening 1 component of the task (poking vs. pulling while twisting out a pair of smooth plastic bolts) but not the other 2. From the subjects' actions on the bolt latch, independent coders could recognize which morph they had witnessed, and they observed a degree of matching to the demonstrator's act consistent with simple imitation or object movement reenactment (A learns from watching B how an object, or parts of an object, move). Thus, these capuchins were capable of more complex social learning than has been recently ascribed to monkeys. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
Tamar Seideman 《Israel journal of chemistry》2005,45(1-2):227-237
Resonances are ubiquitous in molecular heterojunctions and in scanning tunneling microscopy (STM) experiments. In the former environment, resonance tunneling is essential for favorable wire-length-dependence of the conductance and is often the mechanism underlying conductance enhancement through application of a gate voltage. In the latter environment, resonance tunneling has served to develop a powerful vibrational spectroscopy. Resonance conductance is often strongly nonadiabatic; in the course of the tunneling event, electron energy is channelled into vibrational modes and triggers molecular dynamics. The qualitative physics underlying current-driven, resonance-mediated dynamics in molecular electronics is very simple, and is familiar from related phenomena such as gas phase electron-molecule scattering and photochemistry on conducting surfaces. Equilibrium displacement between the initial and resonant states translates into vibronic coupling in the language of the Marcus theory of electron transfer; it produces a nonstationary superposition in the nuclear subspace that evolves during the resonance lifetime. Upon relaxation the system is internally excited and interesting dynamics is likely to ensue. While the underlying physics is very general, the single-molecule STM and molecular heterojunction environments open unique and exciting opportunities. The former introduces the possibility of determining resonance lifetimes through fit of experimental voltage dependencies to a quantum mechanical theory. The latter introduces the possibility of developing coherently driven molecular machines, a new form of nanolithography, and a new means of manipulating the conductivity of molecular-scale devices. We briefly review the theory of current-driven dynamics in molecular-scale devices, discuss the results of ongoing research on surface nanochemistry and molecular machines, and sketch a variety of potential applications. 相似文献
19.
Mendelson Tamar; Thurston Rebecca C.; Kubzansky Laura D. 《Canadian Metallurgical Quarterly》2008,27(4):482
Objective: Observational research suggests subordinate social status is associated with negative mental and physical health outcomes. However, observational studies have limitations, including confounding of social status with other factors, limited ability to infer causality, and difficulty of obtaining detailed affective and physiologic data. This study used experimental methods to test the hypothesis that subordinate social status per se causes psychological distress and cardiovascular arousal. Design: Forty-four women were randomly assigned to an induced subordinate or dominant status condition. Social status was manipulated using a procedure derived from status construction theory. Main Outcome Measures: Affective responses were assessed via self-report. Cardiovascular responses were assessed by measures of systolic and diastolic blood pressures obtained with an automated blood pressure machine. Results: Participants in the subordinate condition perceived themselves as lower in status; the reverse was true for dominant condition participants. Compared with induced dominant status, induced subordinate status produced increased negative affect and systolic blood pressure over the course of the study. Conclusion: Findings suggest social status can be experimentally manipulated and short-term induction of subordinate status can have adverse effects on affect and stress-related physiological systems. Results have implications for understanding how socioeconomic status "gets under the skin" to influence health. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
20.
We hypothesized that computer tools that provide models, opportunity for higher level thinking, and metacognitivelike guidance (e.g., "Can I conjure up an image of the story?") can serve in a learner's zone of proximal development (L. S. Vygotsky, 1978); they can develop competencies through internalization. A computerized Reading Partner presented four reading principles and metacognitivelike questions during the reading of 11 texts over three reading sessions. It was compared with one version that presented the texts with factual and inferential questions and a control version that presented only the texts. Seventh graders using the Reading Partner (n?=?25) reported the expenditure of more mental effort in the process, showed far better metacognitive reconstruction, and improved significantly more in their later reading comprehension and in the quality of their written essays than did the subjects in the other groups. Improvements in reading and writing were statistically accounted for by subjects' ability for metacognitive reconstruction. The study reinforces previous findings pertaining to the role of metacognitions in reading and shows that well-designed computer tools can cultivate competence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献