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1.
Phys Rev Lett ; 132(24): 243401, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38949353

ABSTRACT

We report the creation of ultracold ground state ^{6}Li^{40}K polar molecules with high efficiency. Starting from weakly bound molecules, stimulated Raman adiabatic passage is adopted to coherently transfer the molecules to their singlet rovibrational ground state |X^{1}Σ^{+},v=0,J=0⟩. By employing a singlet stimulated Raman adiabatic passage pathway and low-phase-noise narrow-linewidth lasers, we observed a one-way transfer efficiency of 96(4)%. Held in an optical dipole trap, the lifetime of the ground state molecules is measured to be 5.0(3) ms. The large permanent dipole moment of LiK is confirmed by applying a dc electric field on the molecules and performing Stark shift spectroscopy of the ground state. With recent advances in the quantum control of collisions, our work paves the way for exploring quantum many-body physics with strongly interacting ^{6}Li^{40}K molecules.

2.
bioRxiv ; 2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38712234

ABSTRACT

The sub-ventricular zone (SVZ) is the most well-characterized neurogenic area in the mammalian brain. We previously showed that in 65% of patients with glioblastoma (GBM), the SVZ is a reservoir of cancer stem-like cells that contribute to treatment resistance and emergence of recurrence. Here, we built a single-nucleus RNA-sequencing-based microenvironment landscape of the tumor mass (T_Mass) and the SVZ (T_SVZ) of 15 GBM patients and 2 histologically normal SVZ (N_SVZ) samples as controls. We identified a mesenchymal signature in the T_SVZ of GBM patients: tumor cells from the T_SVZ relied on the ZEB1 regulatory network, whereas tumor cells in the T_Mass relied on the TEAD1 regulatory network. Moreover, the T_SVZ microenvironment was predominantly characterized by tumor-supportive microglia, which spatially co-exist and establish heterotypic interactions with tumor cells. Lastly, differential gene expression analyses, predictions of ligand-receptor and incoming/outgoing interactions, and functional assays revealed that the IL-1ß/IL-1RAcP and Wnt-5a/Frizzled-3 pathways are therapeutic targets in the T_SVZ microenvironment. Our data provide insights into the biology of the SVZ in GBM patients and identify specific targets of this microenvironment.

3.
Opt Lett ; 44(4): 1052-1055, 2019 Feb 15.
Article in English | MEDLINE | ID: mdl-30768054

ABSTRACT

We report experimental results that show the interplay between visibility, distinguishability, and the degree of polarization, as ruled by a recent extension of the polarization coherence theorem (PCT). Theorems of this kind address duality in both quantum and classical scenarios. We particularly focus on the inherent vector nature of the polarization degree of freedom and display various effects that lie beyond the scope of the original PCT. Our results exhibit features that can be shared by quantum and classical phenomena, whenever these phenomena reflect some hidden or exposed coherence.

4.
Mol Neurobiol ; 56(4): 2881-2895, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30069829

ABSTRACT

Resveratrol (RSV) is a natural compound present in berries, grapes and red wine that has shown some neuroprotective properties, but the mechanism by which RSV exhibits its protective role is not very well understood yet. Little is known about the effect of RSV on adenosinergic system, a system regulated in an age-dependent manner in SAMP8 mice, widely considered as an Alzheimer's model. Therefore, the aim of the present work was to assess whether RSV intake was able to modulate the adenosine-mediated signalling in SAMP8 mice. Data showed herein clearly demonstrate the ability of RSV to modulate adenosine receptor gene expression as well as transduction pathway mediated by receptors expressed on plasma membrane. Interestingly, this polyphenol was able to reverse the age-related loss of adenosine A1 receptors and its corresponding signalling pathway. Moreover, adenosine A2A receptors were not modulated by aging or RSV, but A2A-mediated signalling was completely desensitized after RSV treatment compared to untreated mice. Enzymes involved on adenosine metabolism, such as 5'-nucleotidase and adenosine deaminase, were found to be reduced after RSV treatment, but adenosine levels remained unchanged. Nevertheless, an age-related decrease on 5'-nucleotidase activity and adenosine and related metabolite levels was observed. In conclusion, our data show that RSV modulates adenosine-mediated signalling, strongly suggesting that the role of RSV via adenosine receptor signalling and its modulation of neurotransmission in neurodegenerative diseases should be considered as new therapeutic target for RSV neuroprotective effect.


Subject(s)
Adenosine/pharmacology , Aging/metabolism , Resveratrol/pharmacology , Signal Transduction , 5'-Nucleotidase/metabolism , Adenosine Deaminase/metabolism , Adenylyl Cyclases/metabolism , Animals , Cell Membrane/metabolism , Gene Expression Regulation/drug effects , Male , Metabolome , Mice , Receptors, Purinergic P1/genetics , Receptors, Purinergic P1/metabolism , Signal Transduction/drug effects , Weight Gain/drug effects
5.
Exp Gerontol ; 102: 3-11, 2018 02.
Article in English | MEDLINE | ID: mdl-29174969

ABSTRACT

With upcoming age, the capability to fight against harmful stimuli decreases and the organism becomes more susceptible to infections and diseases. Here, the objective was to demonstrate the effect of dietary resveratrol in aged mice in potentiating brain defenses against LipoPolySaccharide (LPS). Acute LPS injection induced a strong proinflammatory effect in 24-months-old C57/BL6 mice hippocampi, increasing InterLeukin (Il)-6, Tumor Necrosis Factor-alpha (Tnf-α), Il-1ß, and C-X-C motif chemokine (Cxcl10) gene expression levels. Resveratrol induced higher expression in those cytokines regarding to LPS. Oxidative Stress (OS) markers showed not significant changes after LPS or resveratrol, although for resveratrol treated groups a slight increment in most of the parameters studies was observed, reaching signification for NF-kB protein levels and iNOS expression. However, Endoplasmic Reticulum (ER) stress markers demonstrated significant changes in resveratrol-treated mice after LPS treatment, specifically in eIF2α, BIP, and ATF4. Moreover, as described, resveratrol is able to inhibit the mechanistic Target of Rapamycin (mTOR) pathway and this effect could be linked to (eIF2α) phosphorylation and the increase in the expression of the previously mentioned proinflammatory genes as a response to LPS treatment in aged animals. In conclusion, resveratrol treatment induced a different cellular response in aged animals when they encountered acute inflammatory stimuli.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Hippocampus/drug effects , Inflammation Mediators/metabolism , Inflammation/prevention & control , Resveratrol/pharmacology , Age Factors , Aging , Animals , Cytokines/genetics , Cytokines/metabolism , Disease Models, Animal , Endoplasmic Reticulum Stress/drug effects , Eukaryotic Initiation Factor-2B/metabolism , Gene Expression Regulation , Hippocampus/metabolism , Inflammation/chemically induced , Inflammation/genetics , Inflammation/metabolism , Lipopolysaccharides , Male , Mice, Inbred C57BL , NF-kappa B/metabolism , Nitric Oxide Synthase Type II/genetics , Nitric Oxide Synthase Type II/metabolism , Oxidative Stress/drug effects , Phosphorylation , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/metabolism
6.
Mol Neurobiol ; 54(3): 1661-1676, 2017 04.
Article in English | MEDLINE | ID: mdl-26873850

ABSTRACT

Metabolic stress induced by high-fat (HF) diet leads to cognitive dysfunction and aging, but the physiological mechanisms are not fully understood. Senescence-accelerated prone mouse (SAMP8) models were conducted under metabolic stress conditions by feeding HF for 15 weeks, and the preventive effect of resveratrol was studied. This dietary strategy demonstrates cognitive impairment in SAMP8-HF and significant preventive effect by resveratrol-treated animals. Hippocampal changes in the proteins involved in mitochondrial dynamics optic atrophy-1 protein (OPA1) and mitofusin 2 (MFN2) comprised a differential feature found in SAMP8-HF that was prevented by resveratrol. Electronic microscopy showed a larger mitochondria in SAMP8-HF + resveratrol (SAMP8-HF + RV) than in SAMP8-HF, indicating increases in fusion processes in resveratrol-treated mice. According to the mitochondrial morphology, significant increases in the I-NDUFB8, II-SDNB, III-UQCRC2, and V-ATPase complexes, in addition to that of voltage-dependent anion channel 1 (VDAC1)/porin, were found in resveratrol-treated animals with regard to SAMP8-HF, reaching control-animal levels. Moreover, tumor necrosis factor alpha (TNF-α) and interleukin (IL-6) were increased after HF, and resveratrol prevents its increase. Moreover, we found that the HF diet affected the Wnt pathway, as demonstrated by ß-catenin inactivation and modification in the expression of several components of this pathway. Resveratrol induced strong activation of ß-catenin. The metabolic stress rendered in the cognitive and cellular pathways altered in SAMP8 focus on different targets in order to act on preventing cognitive impairment in neurodegeneration, and resveratrol can offer therapeutic possibilities for preventive strategies in aging or neurodegenerative conditions.


Subject(s)
Brain/drug effects , Cellular Senescence/drug effects , Mitochondria/drug effects , Stilbenes/pharmacology , Stress, Physiological/drug effects , Wnt Signaling Pathway/drug effects , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Brain/physiology , Cellular Senescence/physiology , Diet, High-Fat/adverse effects , Male , Mice , Mitochondria/physiology , Neuroprotective Agents/pharmacology , Random Allocation , Resveratrol , Wnt Signaling Pathway/physiology
8.
J Phys Condens Matter ; 21(1): 015802, 2009 Jan 07.
Article in English | MEDLINE | ID: mdl-21817230

ABSTRACT

Low-energy (∼0.5 MeV) electrons arising from (60)Co Î³-irradiation were used to create phosphorus-vacancy (PV) pairs and oxygen-vacancy pairs in Czochralski-grown Si. Positron annihilation data show that PV pairs anneal in two stages: the commonly observed stage around 125 °C, where one third of the pairs disappear with an activation energy of 0.8 ± 0.2 eV, and a new stage where none disappear, but form PV-oxygen complexes with an activation energy of 2.0 ± 0.2 eV.

9.
Rev. méd. Chile ; 131(10): 1101-1110, oct. 2003.
Article in Spanish | LILACS | ID: lil-355988

ABSTRACT

BACKGROUND: Intraventricular resynchronization with pacemakers is a promising therapy for patients with refractory cardiac failure and intraventricular conductions delay. However its long term effects are not well known. AIM: To report the results of this therapy in patients with cardiac failure. PATIENTS AND METHODS: Fourteen patients (11 male), whose mean age was 68 years, with a severe and refractory cardiac failure, have been treated in our unit using intraventricular resynchronization with pacemakers. Eight had a coronary heart disease and six a dilated myocardiopathy. The pacemaker was implanted transvenously, with conventional stimulation in atrium and right ventricle. The left ventricle was stimulated through an epicardial vein, accessed through the coronary sinus. RESULTS: In one patient the high thresholds did not allow a left ventricular stimulation. In the other 13 patients, a clinical improvement was observed in 11 (85 per cent), that has been sustained for a mean of 8.2 months. The ejection fraction improved form 23.5 to 32.4 per cent (p < 0.001), the 6 min walking test improved from 347 to 437 m (p = 0.003) and the functional capacity changes from 3.3 to 2.7 (p < 0.001). Three patients died during follow up. One was the patient in whom the stimulation failed and two had a sudden death. No complications of the procedure were observed. CONCLUSIONS: In this series, intraventricular resynchronization with pacemakers was effective in 11 of 13 patients, improving functional capacity and ejection fraction. Sudden death could be avoided adding a defibrillator to the pacemaker system.


Subject(s)
Humans , Male , Female , Middle Aged , Cardiac Pacing, Artificial/methods , Cardiomyopathy, Dilated/therapy , Coronary Disease/therapy , Ventricular Dysfunction/physiopathology , Pacemaker, Artificial , Treatment Outcome , Stroke Volume
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