Tetrazine-based bio-orthogonally activated fluorogenic probes have drawn great attention due to their excellent performance in bioimaging; however, most of them suffer from aggregation-caused ...quenching (ACQ) problems. Herein, we developed a set of novel tetrazine-modified tetraphenylenes (TPEs) as bio-orthogonally activated aggregation-induced emission (AIE) fluorogenic probes. Both the fluorescence and AIE features are quenched by tetrazine, which is mediated by the through-bond energy-transfer (TBET) mechanism, and are activated upon converting tetrazine to pyridazine
via
the inverse electron-demand Diels-Alder (iEDDA) reaction. The activated cycloadducts displayed a notable fluorescence enhancement, a large Stokes shift, a high fluorescence quantum yield, and evident AIE-active features. Manipulating the length and position of the π-linker enables fine-tuning of the photophysical properties of the probes, while an overlong planar π-linker leads to AIE-to-ACQ transformation. We also designed bi-tetrazyl-substituted probes, which exhibited a higher turn-on ratio than the mono-tetrazyl analogs owing to the 'double-quenched' function. When they reacted with double-clickable linkers, fluorescent macrocycles were obtained because of the restriction of the free rotation of the phenyl rings of TPE. Using an organelle-pretargeting strategy, we succeeded in applying these probes for mitochondria-specific bio-orthogonal imaging in live cells under no-wash conditions, which is expected to provide a powerful tool for biomedical applications.
Tetraphenylene-tetrazine derivatives were developed as bio-orthogonally activated aggregation-induced emission (AIE)-type fluorogenic probes for live-cell imaging.
OBJECTIVETo investigate the occurrence and the influencing factors of post-stroke depression (PSD) in first-episode stroke. METHODSA total of 350 elderly stroke patients who were admitted to Wuxi ...Central Rehabilitation Hospital for the first time from January 2020 to December 2020 were enrolled in this study. The Hamilton Depression Scale (HAMD) was used to evaluate the depression status of stroke patients. The sociodemographic data, clinical symptoms, social environment and behavioral patterns of the patients were collected to analyze the related factors of depression after stroke through SPSS 20.0 software. RESULTSThe incidence of PSD was 45.71%. There were statistical differences among different gender, lesion nature, lesion location, smoking, hypertension, diabetes, hospitalization enpenses, season of onset, BMI index, NIHSS score, barthel index score, blood pressure variation coefficient and other factors (p = 0.000). Post-stroke depression score was positively correlated with NIHSS score and coefficient of variation of systolic blood pressure (r = 0.935, p = 0.000; r = 0.921, p = 0.000), and negatively correlated with barthel index score (r = -0.964, p = 0.000). Through multivariate Logistic regression analysis, it was found that male (OR=8.624, 95%CI: 5.672-11.715), cerebral infarction (OR=2.561, 95%CI: 1.256-3.567), and the right side lesion (OR=1.933, 95%CI: 1.024-3.026), smoking (OR=2.457, 95%CI: 1.611-3.625), onset in autumn and winter (OR=2.049, 95%CI: 1.201-2.919), high BMI (OR=2.461, 95%CI): 1.426-3.432) were risk factors for depression after stroke, and low SBPV (OR=0.567, 95%CI: 0.352-0.758) and low NISHH score (OR=0.256, 95%CI: 0.105-0.486) were the protective factor for subsequent depression of stroke. CONCLUSIONMales, smoking, patients with onset in autumn and winter, lesions on the right side, high BMI, high NISHH score and high systolic blood pressure variation were closely related to PSD, which should be paid for attention for such patients to prevent the occurrence of PSD and take intervention measures.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Glaesserella parasuis (G. parasuis) can cause peritonitis in piglets. However, the pathogenesis of peritonitis remains unclear. Baicalin has been shown to possess anti-inflammatory and anti-oxidant ...functions. The aim of this study was to investigate the role of the PANX-1/P2X7 axis and the P2Y6 signaling pathway in peritonitis induced by G. parasuis and the effect of baicain on the PANX-1/P2X7 axis and P2Y6 pathway activation triggered by G. parasuis. A G. parasuis serovar 5 isolate SH0165 strain was obtained from the lungs of commercially produced pigs which had the typical symptoms of Glässer’s disease, namely arthritis, fibrinous polyserositis, hemorrhagic pneumonia, and meningitis. Then, 35 piglets were randomly divided into five groups, each group containing seven piglets. The groups consisted of a negative control group, an infection group, a 25 mg/kg baicalin group, a 50 mg/kg baicalin group, and a 100 mg/kg baicalin group. The results showed that G. parasuis could promote PANX-1/P2X7 axis and P2Y6 activation; induce NLRP3/caspase-1, IL-1β and IL-18 expression; trigger PLC/PKC and MLCK/MLC signaling activation; attenuate the expression of tight junction proteins ZO-1, E-cadherin, Occludins, and claudin 1; and stimulate CD14, CD24, CD36, CD47, and CD91 expression in the peritoneum as measured via Western blot (p < 0.01; PLC, p < 0.05). Baicalin could significantly inhibit PANX-1/P2X7 axis, P2Y6, and NLRP3/caspase-1 activation; reduce IL-1β and IL-18 expression; attenuate PLC/PKC and MLCK/MLC activation; promote ZO-1, E-cadherin, occludins, and claudin 1 expression; and reduce CD14, CD24, CD36, CD47, and CD91 expression in the peritoneum induced by G. parasuis as measured via Western blot. Our results deepen the understanding of the mechanism of peritonitis triggered by G. parasuis and provide some novel potential methods of controlling G. parasuis infection.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Invigorated by the high temperature superconductivity in some binary hydrogen-dominated compounds, we systematically explored high-pressure phase diagrams and superconductivity of a ternary Mg-Ge-H ...system using
ab initio
methods. Stoichiometric MgGeH
6
with high hydrogen content exhibiting
Pm
3&cmb.macr; symmetry was predicted from a series of high-pressure synthesis paths. We performed an in-depth study on three distinct formation routes to MgGeH
6
,
i.e.
, Mg + Ge + 3H
2
→ MgGeH
6
, MgGe + 3H
2
→ MgGeH
6
and MgH
2
+ GeH
4
→ MgGeH
6
at high pressures. By directly squeezing three elemental solids Mg + Ge + 3H
2
, we obtained ternary MgGeH
6
at 200 GPa. By adding a little bit of the MgGe alloy into hydrogen, we found that MgGeH
6
can form and stabilize at about 200 GPa. More intriguingly, upon compressing MgH
2
and GeH
4
to 250 GPa, we also predicted the same MgGeH
6
. Electron structure calculations reveal that the cubic MgGeH
6
is a good metal and takes on ionic character. Electron-phonon coupling calculation reveals a large
λ
= 1.16 for MgGeH
6
at 200 GPa. In particular, we found that ternary MgGeH
6
could be a potential high temperature superconductor with a superconducting transition temperature
T
c
of ∼67 K at 200 GPa.
Invigorated by the high temperature superconductivity in some binary hydrogen-dominated compounds, we systematically explored high-pressure phase diagrams and superconductivity of a ternary Mg-Ge-H system using
ab initio
methods.
Invigorated by the high temperature superconductivity in some binary hydrogen-dominated compounds, we systematically explored high-pressure phase diagrams and superconductivity of a ternary Mg-Ge-H ...system using ab initio methods. Stoichiometric MgGeH
with high hydrogen content exhibiting Pm3combining macron symmetry was predicted from a series of high-pressure synthesis paths. We performed an in-depth study on three distinct formation routes to MgGeH
, i.e., Mg + Ge + 3H
→ MgGeH
, MgGe + 3H
→ MgGeH
and MgH
+ GeH
→ MgGeH
at high pressures. By directly squeezing three elemental solids Mg + Ge + 3H
, we obtained ternary MgGeH
at 200 GPa. By adding a little bit of the MgGe alloy into hydrogen, we found that MgGeH
can form and stabilize at about 200 GPa. More intriguingly, upon compressing MgH
and GeH
to 250 GPa, we also predicted the same MgGeH
. Electron structure calculations reveal that the cubic MgGeH
is a good metal and takes on ionic character. Electron-phonon coupling calculation reveals a large λ = 1.16 for MgGeH
at 200 GPa. In particular, we found that ternary MgGeH
could be a potential high temperature superconductor with a superconducting transition temperature T
of ∼67 K at 200 GPa.
The critical role of the tumor immune microenvironment (TIME) in determining response to immune checkpoint inhibitor (ICI) therapy underscores the importance of understanding cancer cell-intrinsic ...mechanisms driving immune-excluded ("cold") TIMEs. One such cold tumor is oral cavity squamous cell carcinoma (OSCC), a tobacco-associated cancer with mutations in the TP53 gene which responds poorly to ICI therapy. Because altered TP53 function promotes tumor progression and plays a potential role in TIME modulation, here we developed a syngeneic OSCC models with defined Trp53 (p53) mutations and characterized their TIMEs and degree of ICI responsiveness. We observed that a carcinogen-induced p53 mutation promoted a cold TIME enriched with immunosuppressive M2 macrophages highly resistant to ICI therapy. p53-mutated cold tumors failed to respond to combination ICI treatment; however, the combination of a programmed cell death protein 1 (PD-1) inhibitor and stimulator of interferon genes (STING) agonist restored responsiveness. These syngeneic OSCC models can be used to gain insights into tumor cell-intrinsic drivers of immune resistance and to develop effective immunotherapeutic approaches for OSCC and other ICI-resistant solid tumors.
The behavior of molecules and molecular chains confined in 1D nanochannels imposed by external interactions is a problem of fundamental interest. Here, we report structural manipulation of iodine ...confined inside zeolite (AFI) nanochannels by the application of high pressure. Structural transformations of the confined iodine under pressure have been unambiguously identified by polarized Raman spectroscopy combined with theoretical simulation. The length of the iodine chains and the orientation and intermolecular interaction of the confined iodine have been tuned at the molecular level by applied pressure. Almost all the confined iodine can be tuned into an axially oriented state upon compression, favoring the formation of long chains. The long iodine chains can be preserved to ambient pressure when released from intermediate pressures.
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IJS, KILJ, NUK, PNG, UL, UM
Unique structures and properties will be introduced upon compression. To figure out the high pressure crystal structure of XeF2, in situ synchrotron X-ray diffraction, Raman spectra, UV–vis ...absorption spectra, and theoretical calculations have been performed up to 86 GPa. The structural dispute between reported experimental and theoretical results is settled by this study. The experimental and theoretical Raman spectra results indicated that the ambient structure of XeF2 (I4/mmm) transformed into a Immm structure at 28 GPa. Then this Immm structure transformed into Pnma structure at 59 GPa. The Rietveld refinement of the XRD results was in accordance with our Raman study. The optical absorption spectra revealed a reduction in the band gap as pressure increases. The reduction in the band gap decreases to 1.83 eV at 82 GPa while the color of the sample is getting dark. Our results provide a new insight into the high pressure behavior of noble gas compounds with the example of XeF2.
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IJS, KILJ, NUK, PNG, UL, UM
The crystal structures and properties of hafnium hydride under pressure are explored using the first-principles calculations based on density function theory. The material undergoes pressure-induced ...structural phase transition I4/mmm → Cmma → P21/m at 180 and 250 GPa, respectively, and all of these structures are metallic. The superconducting critical temperature Tc values of I4/mmm, Cmma, and P21/m are 47-193 mK, 5.99-8.16 K and 10.62-12.8 K at 1 atm, 180 and 260 GPa, respectively. Furthermore, the bonding nature of HfH2 is investigated with the help of the electron localization function, the difference charge density and Bader charge analyses, which show that HfH2 is classified as a ionic crystal with the charges transferring from Hf atom to H.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Single-crystalline C60·1m-xylene nanorods with a hexagonal structure were successfully synthesized by evaporating a C60 solution in m-xylene at room temperature. The ratio of the length to the ...diameter of the nanorods can be controlled in the range of ≈10 to over 1000 for different applications. The photoluminescence (PL) intensity of the nanorods is about 2 orders of magnitude higher than that for pristine C60 crystals in air. Both UV and Raman results indicate that there is no charge transfer between C60 and m-xylene. It was found that the interaction between C60 and m-xylene molecules is of the van der Waals type. This interaction reduces the icosahedral symmetry of C60 molecule and induces strong PL from the solvate nanorods.
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IJS, KILJ, NUK, PNG, UL, UM
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