Na3V2(PO4)2F3 is a positive electrode material for Na-ion batteries which is attracting strong interest due to its high capacity, rate capability, and long-term cycling stability. The sodium ...extraction mechanism from this material has been always described in the literature as a straightforward solid solution, but several hints point toward a more complicated phase diagram. In this work we performed high angular resolution synchrotron radiation diffraction measurements, realized operando on sodium batteries upon charge. We reveal an extremely interesting phase diagram, created by the successive crystallization of four intermediate phases before the end composition NaV2(PO4)2F3 is reached. Only one of these phases undergoes a solid solution reaction, in the interval between 1.8 and 1.3 Na per formula unit. The ability to resolve weak Bragg reflections allowed us to reveal differences in terms of symmetry among the phases, to determine their previously unknown space groups, and to correlate them with sodium (dis)ordering in the structure. Rietveld refinements enabled us to follow fine structural modifications in great detail. Intermediate identified phases are not simply described by their unit cell parameters, but bond-length variations can be tracked, as well as polyhedral distortions and site occupancy factors for mobile sodium ions. For NaV2(PO4)2F3 a full crystal structure determination was also carried out for the first time directly from operando measurements, assigning it to the Cmc21 space group and revealing two vanadium environments: V3+ and V5+. Our study demonstrates that improved angular resolution and high intensity diffraction data are key parameters for direct observation of fine reaction pathways in electrode materials and that the obtained insight is crucial for the understanding of (de)intercalation mechanisms in Na-ion batteries.
Both cell-cell adhesion and oriented cell division play prominent roles in establishing tissue architecture, but it is unclear how they might be coordinated. Here, we demonstrate that the cell-cell ...adhesion protein E-cadherin functions as an instructive cue for cell division orientation. This is mediated by the evolutionarily conserved LGN/NuMA complex, which regulates cortical attachments of astral spindle microtubules. We show that LGN, which adopts a three-dimensional structure similar to cadherin-bound catenins, binds directly to the E-cadherin cytosolic tail and thereby localizes at cell-cell adhesions. On mitotic entry, NuMA is released from the nucleus and competes LGN from E-cadherin to locally form the LGN/NuMA complex. This mediates the stabilization of cortical associations of astral microtubules at cell-cell adhesions to orient the mitotic spindle. Our results show how E-cadherin instructs the assembly of the LGN/NuMA complex at cell-cell contacts, and define a mechanism that couples cell division orientation to intercellular adhesion.
Na3V2(PO4)2F3 is a material that has been attracting great interest as a potential positive electrode for Na-ion batteries. Its crystal structure was determined from single-crystal X-ray diffraction ...in 1999 by Le Meins et al. in the tetragonal space group P42/mnm at 298 K. In this work, we show how the use of very high angular resolution synchrotron radiation diffraction reveals a subtle orthorhombic distortion with unit-cell parameters of a = 9.02847(3) Å, b = 9.04444(3) Å, c = 10.74666(6) Å in the Amam space group. Although this only slightly impacts the structural framework of the material, it reveals a significantly modified distribution of Na ions. Furthermore, the crystal structure of the high-temperature form of Na3V2(PO4)2F3 (at 400 K) was determined for the first time. This allowed comparing the totally disordered distribution of Na ions in this case with the partially ordered one of the room-temperature phase. We report here on an original structure and on an original electrochemical signature for stoichiometric Na3V2(PO4)2F3, and we propose that fluctuations in the O/F ratio are at the origin of discrepancies found in the literature.
Literature has demonstrated hypoglossal nerve stimulation to be a safe and effective treatment for patients with obstructive sleep apnea nonadherent to positive airway pressure therapy. However, the ...recommended criteria for patient selection are still unable to identify all the unresponsive patients, highlighting the need for improved understanding about hypoglossal nerve stimulation for obstructive sleep apnea.
A 48-year-old Caucasian male patient with obstructive sleep apnea had been successfully treated with electrical stimulation of the hypoglossal nerve trunk, documented by level 1 polysomnography data. However, due to snoring complaints, he underwent postoperation drug-induced sleep endoscopy for evaluation of electrode activation during upper airway collapse, aiming to improve electrostimulation parameters. Concurrent surface electromyography of the suprahyoid muscles and masseter was obtained. Activation of electrodes 2, 3, and 6 promoted upper airway opening most strongly at the velopharynx and tongue base during drug-induced sleep endoscopy. The same channels also significantly increased the electrical activity on suprahyoid muscles bilaterally, but predominantly on the stimulated side (right). The masseters also presented a considerable asymmetry in electrical potential on the right side (> 55%).
Beyond the genioglossus muscle, our findings demonstrate recruitment of other muscles during hypoglossal nerve stimulation, which may be attributed to the electrical stimulation of the nerve trunk. This data provides new insights on how stimulation of the hypoglossal nerve trunk may contribute to obstructive sleep apnea treatment.
Background
The aim of this study was to compare different surgical therapies to treat peri‐implantitis.
Methods
Twenty‐three patients presenting one implant affected by peri‐implantitis were divided ...into three groups: (i) open flap debridement (OFD) and citric acid decontamination (CAD); (ii) OFD, CAD and subepithelial connective tissue graft (SCTG); (iii) OFD, CAD and implantoplasty. Modified plaque index (MPI), gingival bleeding index (GBI), keratinized mucosa (KM) width, probing depth (PD), bleeding or suppuration on probing (B/SOP), and radiographic crestal bone level were registered 1(T1), 2(T2) and 3(T3) years after treatment.
Results
In Group 1 there was a significant improvement in MPI from baseline to T1, and a significant reduction in PD over time. In Group 2, none of the assessed clinical parameters showed any statistically significant variation over time. In Group 3, there was a significant decrease in PD and B/SOP over time. When comparing the 3 Groups, KM was significanlty greater in Group 2 vs. Group 1 and Group 3 at T1 and T2, and in Group 2 vs. Group 3 at T3.
Conclusion
All therapies were successful in the management of peri‐implantitis; however, SCTG maintained the greatest KM width. Surgical therapies combined with mechanical and chemical decontamination contributed to peri‐implant tissue health.
Cell adhesions link cells to the extracellular matrix (ECM) and to each other and depend on interactions with the actin cytoskeleton. Both cell-ECM and cell-cell adhesion sites contain discrete, yet ...overlapping, functional modules. These modules establish physical associations with the actin cytoskeleton, locally modulate actin organization and dynamics, and trigger intracellular signaling pathways. Interplay between these modules generates distinct actin architectures that underlie different stages, types, and functions of cell-ECM and cell-cell adhesions. Actomyosin contractility is required to generate mature, stable adhesions, as well as to sense and translate the mechanical properties of the cellular environment into changes in cell organization and behavior. Here, we review the organization and function of different adhesion modules and how they interact with the actin cytoskeleton. We highlight the molecular mechanisms of mechanotransduction in adhesions and how adhesion molecules mediate cross talk between cell-ECM and cell-cell adhesion sites.
Osteoarthritis (OA) is a common disease in the elderly people, inducing pain and functional limitations. Clodronate (CLO) a first generation non-nitrogen containing bisphosphonate has been purposed ...as a treatment of OA, being effective on pain, inflammation, bone marrow oedema, osteophytosis and cartilage regeneration. Intra-muscular routes of CLO showed efficacy in the treatment of Knee OA (KOA) and erosive OA of the hand. In KOA intraarticular CLO at low doses (0.5-2 mg) showed efficacy as well as hyaluronic acid (HA), being able to improve the effectiveness if associated to HA.
Nine Consecutive patients (4 female, 5 male, mean age 78,22) with KOA at 2nd or 3rd degree following Kellgren-Lawrance scale, non responder to HA and unintended to surgery. They were treated with intraarticular CLO at the weekly dose of 20 mg, plus lidocaine 1% in 5 cc of saline solution for a route of 5 weekly infil-trations, followed by a second route of 5 intraarticular infiltrations 3 months after the first course. Visual analog score (VAS) pain and Tegner-Lysholm Score (TLS) were used to assess changes following CLO treatment.
Baseline pain was 6,77/10, reduced to 1,09 at day 150 (after second course) and to 2,3/10 at day 240. TLS at baseline was 56,7/100, improved to 96,7 at day 150 and to 84,1 at day 240. At day 240 only 2 out of 9 patients had a negative judgement of the treatment and decided to stop it, while 7 were satisfied and available to a further course. There was no increase of consumption of anti-inflammatory or analgesic drugs. A short time lasting pain after the injections was registered in all patients.
In a small cohort of patients affected by KOA, non responders to intraarticular HA a higher dose of intraarticular CLO in KOA showed good compliance, amelioration of pain and functionality.
Laser microirradiation coupled with live-cell fluorescence microscopy is a powerful technique that has been used widely in studying the recruitment and retention of proteins at sites of DNA damage. ...Results obtained from this technique can be found in published works by both seasoned and infrequent users of microscopy. However, like many other microscopy-based techniques, the presentation of data from laser microirradiation experiments is inconsistent; papers report a wide assortment of analytic techniques, not all of which result in accurate and/or appropriate representation of the data. In addition to the varied methods of analysis, experimental and analytical details are commonly under-reported. Consequently, publications reporting data from laser microirradiation coupled with fluorescence microscopy experiments need to be carefully and critically assessed by readers. Here, we undertake a systematic investigation of commonly reported corrections used in the analysis of laser microirradiation data. We validate the critical need to correct data for photobleaching and we identify key experimental parameters that must be accounted for when presenting data from laser microirradiation experiments. Furthermore, we propose a straightforward, four-step analytical protocol that can readily be applied across platforms and that aims to improve the quality of data reporting in the DNA damage field.
•Published analyses of laser microirradiation data are often incomplete or invalid.•Methods of analysis used are often under-reported, impacting data validity.•We assess commonly used and commonly overlooked analytical approaches.•This study describes a straightforward and readily implemented method of analysis.•Normalization and correction for background and photobleaching are essential steps.
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