7,795 research outputs found
A multichannel thiacalix[4]arene-based fluorescent chemosensor for Zn²⁺, F⁻ ions and imaging of living cells
The fluorescent sensor (3) based on the 1,3-alternate conformation of the thiacalix[4]arene bearing the coumarin fluorophore, appended via an imino group, has been synthesised. Sensing properties were evaluated in terms of a colorimetric and fluorescence sensor for Zn 2+ and F - . High selectivity and excellent sensitivity were exhibited, and off-on optical behaviour in different media was observed. All changes were visible to the naked eye, whilst the presence of the Zn 2+ and F - induces fluorescence enhancement and the formation of a 1:1 complex with 3. In addition, 3 exhibits low cytotoxicity and good cell permeability and can readily be employed for assessing the change of intracellular levels of Zn 2+ and F -
Long-range and short-range tumor-stroma networks synergistically contribute to tumor-associated epilepsy
Epileptic seizures are frequently caused by brain tumors. Traditional anti-epileptic treatments do not acquire satisfactory responses. Preoperative and postoperative seizures seriously influence the quality of life of patients. Thus, tumor-associated
epilepsy (TAE) is an important subject of the current research. The delineation of the
etiology of epileptogenesis in patients with primary brain tumor may help to find the
novel and effective drug targets for treating this disease. In this review, we describe
the current status of treatment of TAE. More importantly, we focus on the factors
that are involved in the functional connectivity between tumors and stromal cells.
We propose that there exist two modes, namely, long-range and short-range modes,
which likely trigger neuronal hyperexcitation and subsequent epileptic seizures. The
long-range mode is referred to as factors released by tumors including glutamate
and GABA, binding to the corresponding receptor on the cellular membrane and
causing neuronal hyperactivity, while the short-range mode is considered to involve
direct intracellular communication between tumor cells and stromas. Gap junctions
and tunneling nanotube network are involved in cellular interconnections. Future
investigations focused on those two modes may find a potential novel therapeutic
target for treating TAE
Period-2: a tumor suppressor gene in breast cancer
Previous reports have suggested that the ablation of the Period 2 gene (Per 2) leads to enhanced development of lymphoma and leukemia in mice. Employing immunoblot analyses, we have demonstrated that PER 2 is endogenously expressed in human breast epithelial cell lines but is not expressed or is expressed at significantly reduced level in human breast cancer cell lines. Expression of PER 2 in MCF-7 breast cancer cells significantly inhibited the growth of MCF-7 human breast cancer cells, and, when PER 2 was co-expressed with the Crytochrome 2 (Cry 2) gene, an even greater growth-inhibitory effect was observed. The inhibitory effect of PER 2 on breast cancer cells was also demonstrated by its suppression of the anchorage-independent growth of MCF-7 cells as evidenced by the reduced number and size of colonies. A corresponding blockade of MCF-7 cells in the G1 phase of the cell cycle was also observed in response to the expression of PER 2 alone or in combination with CRY 2. Expression of PER 2 also induced apoptosis of MCF-7 breast cancer cells as demonstrated by an increase in PARP [poly (ADP-ribose) polymerase] cleavage. Finally, our studies demonstrate that PER 2 expression in MCF-7 breast cancer cells is associated with a significant decrease in the expression of cyclin D1 and an up-regulation of p53 levels
A “Double-Multi” Model for Electromigration of Lithiums and Chlorides in ASR Affected Concrete
Existing reinforced concrete structures experience severe durability degradation when subjected to alkali– silica reaction (ASR) and chloride attack. A special electrochemical rehabilitation treatment, containing lithium compound anolyte, has been developed to drive lithium ions into concrete as well as remove chlorides simultaneously, for mitigating both the ASR-induced cracks and the chloride-induced corrosion. Good performance of introduced lithiums in controlling ASR-induced expansion has already been proved. Unfortunately, the migration mechanism of lithium in concrete under an external electric field is seldom investigated in existing literature. In this study, with help of the “double-multi” model, the efficiency of impregnation of lithium ions and simultaneously the removal of chloride ions through a specific electrochemical treatment are numerically evaluated, which results into the distribution profiles of all typical ionic species. The heterogeneous concrete model examines the aggregate effect, especially on the interaction with lithiums which are supposed to mitigate ASR. The ionic interaction between different species and the electrochemical reaction at electrodes are also considered. Through a relative thorough modelling of multi-phase and multi-species, a systemic parametric analysis based on a series of significant factors during electrochemical treatment (e.g., current density, treatment time, temperature, cathode position and concentration of lithium solution) reveals some important tendencies of ionic electromigration in concrete, which are supposed to guide the field application
Inhibition of breast cancer cell invasion by melatonin is mediated through regulation of the p38 mitogen-activated protein kinase signaling pathway
Elevation of Inducible Nitric Oxide Synthase and Cyclooxygenase-2 Expression in the Mouse Brain after Chronic Nonylphenol Exposure
The present study was performed to investigate the effects of chronic administration of nonylphenol (NP) on the expression of inflammation-related genes in the brains of mice. NP was given orally by gavages at 0, 50, 100, and 200 mg/kg/d. The expression of inflammatory enzymes, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), was evaluated by immunohistochemistry and immunoblotting assays. The nitric oxide (NO) level and nitric oxide synthase (NOS) activity were also measured by biochemical analyses. The results showed that NP at a high dose (200 mg/kg/d) significantly increased the expression of iNOS and COX-2 in both the hippocampus and cortex. In parallel with the increase in iNOS expression, the NO level was significantly greater at the dose of 200 mg/kg/d, compared to the control. The activity of NOS was also increased in the brain of mice at the dose of 100 and 200 mg/kg/d. These findings demonstrate that NP may have the potential to induce the chronic inflammation or cause neurotoxicity in the mouse brain
VENUS: A Geometrical Representation for Quantum State Visualization
Visualizations have played a crucial role in helping quantum computing users
explore quantum states in various quantum computing applications. Among them,
Bloch Sphere is the widely-used visualization for showing quantum states, which
leverages angles to represent quantum amplitudes. However, it cannot support
the visualization of quantum entanglement and superposition, the two essential
properties of quantum computing. To address this issue, we propose VENUS, a
novel visualization for quantum state representation. By explicitly correlating
2D geometric shapes based on the math foundation of quantum computing
characteristics, VENUS effectively represents quantum amplitudes of both the
single qubit and two qubits for quantum entanglement. Also, we use multiple
coordinated semicircles to naturally encode probability distribution, making
the quantum superposition intuitive to analyze. We conducted two well-designed
case studies and an in-depth expert interview to evaluate the usefulness and
effectiveness of VENUS. The result shows that VENUS can effectively facilitate
the exploration of quantum states for the single qubit and two qubits
Tracking the nematicity in cuprate superconductors: a resistivity study under uniaxial pressure
Overshadowing the superconducting dome in hole-doped cuprates, the pseudogap
state is still one of the mysteries that no consensus can be achieved. It has
been suggested that the rotational symmetry is broken in this state and may
result in a nematic phase transition, whose temperature seems to coincide with
the onset temperature of the pseudogap state around optimal doping level,
raising the question whether the pseudogap results from the establishment of
the nematic order. Here we report results of resistivity measurements under
uniaxial pressure on several hole-doped cuprates, where the normalized slope of
the elastoresistivity can be obtained as illustrated in iron-based
superconductors. The temperature dependence of along particular lattice
axis exhibits kink feature at and shows Curie-Weiss-like behavior above
it, which may suggest a spontaneous nematic transition. While seems to
be the same as around the optimal doping and in the overdoped region,
they become very different in underdoped LaSrCuO. Our results
suggest that the nematic order, if indeed existing, is an electronic phase
within the pseudogap state.Comment: 6 pages, 4 figure
5-Bromo-1-methylindolin-2-one
The title molecule, C9H8BrNO, approximates a full planar conformation. The interplanar angle between the benzene and five-membered rings of the indoline system is 1.38 (1)°. There is an obvious π-delocalization involving the N—C=O group in the five-membered ring, which is greater than that involving the N—C C(benzene) group
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