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1.
Nature ; 621(7979): 493-498, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37437603

RESUMO

Although high-transition-temperature (high-Tc) superconductivity in cuprates has been known for more than three decades, the underlying mechanism remains unknown1-4. Cuprates are the only unconventional superconductors that exhibit bulk superconductivity with Tc above the liquid-nitrogen boiling temperature of 77 K. Here we observe that high-pressure resistance and mutual inductive magnetic susceptibility measurements showed signatures of superconductivity in single crystals of La3Ni2O7 with maximum Tc of 80 K at pressures between 14.0 GPa and 43.5 GPa. The superconducting phase under high pressure has an orthorhombic structure of Fmmm space group with the [Formula: see text] and [Formula: see text] orbitals of Ni cations strongly mixing with oxygen 2p orbitals. Our density functional theory calculations indicate that the superconductivity emerges coincidently with the metallization of the σ-bonding bands under the Fermi level, consisting of the [Formula: see text] orbitals with the apical oxygen ions connecting the Ni-O bilayers. Thus, our discoveries provide not only important clues for the high-Tc superconductivity in this Ruddlesden-Popper double-layered perovskite nickelates but also a previously unknown family of compounds to investigate the high-Tc superconductivity mechanism.

2.
Proc Natl Acad Sci U S A ; 121(12): e2321540121, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38483993

RESUMO

Nitrogen doped lutetium hydride has drawn global attention in the pursuit of room-temperature superconductivity near ambient pressure and temperature. However, variable synthesis techniques and uncertainty surrounding nitrogen concentration have contributed to extensive debate within the scientific community about this material and its properties. We used a solid-state approach to synthesize nitrogen doped lutetium hydride at high pressure and temperature (HPT) and analyzed the residual starting materials to determine its nitrogen content. High temperature oxide melt solution calorimetry determined the formation enthalpy of LuH1.96N0.02 (LHN) from LuH2 and LuN to be -28.4 ± 11.4 kJ/mol. Magnetic measurements indicated diamagnetism which increased with nitrogen content. Ambient pressure conductivity measurements observed metallic behavior from 5 to 350 K, and the constant and parabolic magnetoresistance changed with increasing temperature. High pressure conductivity measurements revealed that LHN does not exhibit superconductivity up to 26.6 GPa. We compressed LHN in a diamond anvil cell to 13.7 GPa and measured the Raman signal at each step, with no evidence of any phase transition. Despite the absence of superconductivity, a color change from blue to purple to red was observed with increasing pressure. Thus, our findings confirm the thermodynamic stability of LHN, do not support superconductivity, and provide insights into the origins of its diamagnetism.

3.
Inorg Chem ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970479

RESUMO

Neodymium monoxide (NdO) is a metastable rare earth oxide material with a unique electronic structure, which has potential applications across various fields such as semiconductors, energy, catalysis, laser technology, and advanced communications. Despite its promising attributes, the thermodynamic properties of NdO remain unexplored. In this study, high pressure, high temperature phases of neodymium monoxide (NdO, with a rocksalt structure) and body-centered cubic (bcc) Nd metal were synthesized at 5 GPa and 1473 K. X-ray photoelectron spectroscopy (XPS) measurements indicate that the Nd 3d peak shifts to higher energy in NdO relative to Nd2O3, suggesting the possibility of complex electronic states in NdO. Formation enthalpies for the reaction 1/3Nd2O3 + 1/3bcc Nd = NdO obtained from high temperature solution calorimetry in molten sodium molybdate and for the reaction dhcp Nd (metal) = bcc Nd (metal) from differential scanning calorimetry are 25.98 ± 8.65 and 5.2 kJ/mol, respectively. Utilizing these enthalpy values, we calculated the pressure-temperature boundary for the reaction 1/3 bcc Nd + 1/3Nd2O3 = NdO, which has a negative P-T slope of -1.68× 10-4 GPa/K. These insights reveal the high pressure behavior of NdO and neodymium metal, underscoring their potential utility in technological applications.

4.
Anal Chem ; 94(2): 1308-1317, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34962779

RESUMO

Alterations in formaldehyde (FA) homeostasis are associated with the pathology of Alzheimer's disease (AD). In vivo tracking of FA flux is important for understanding the underlying molecular mechanisms, but is challenging due to the lack of sensitive probes favoring a selective, rapid, and reversible response toward FA. In this study, we re-engineered the promiscuous and irreversible phenylhydrazines to make them selective and reversible toward FA by tuning their nucleophilicity. This effort resulted in PFM309, a selective (selectivity coefficient KFA,methylglyoxal = 0.06), rapid (t1/2 = 32 s at [FA] = 200 µM), and reversible fluorogenic probe (K = 6.24 mM-1) that tracks the FA flux in both live cells and live mice. In vivo tracking of the FA flux was realized by PFM309 imaging, which revealed the gradual accumulation of FA in the live mice brain during normal aging and its further increase in AD mice. We further identified the age-dependent loss of catabolism enzymes ALDH2 and ADH5 as the primary mechanism responsible for formaldehyde excess. Activating ALDH2 with the small molecular activator Alda1 significantly protected neurovascular cells from formaldehyde overload and consequently from impairment during AD progress both in vitro and in vivo. These findings revealed PFM309 as a robust tool to study AD pathology and highlight ALDH2 as a potential target for AD drug development.


Assuntos
Doença de Alzheimer , Envelhecimento , Aldeído-Desidrogenase Mitocondrial/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Animais , Formaldeído/metabolismo , Camundongos
5.
Inorg Chem ; 60(15): 11579-11590, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34259522

RESUMO

The rational design of multifunctional inorganic pigments relies on the manipulation of ionic valence and local surroundings of a chromophore in structurally and chemically habitable hosts. To date, the development of environmentally benign and intense violet/purple pigments is still a challenge. Here we report a family of A3-xMnxTeO6 and A3-2xMnxLixTeO6 (A = Zn, Mg; x = 0.01-0.15) pigments colored by site-selective Mn2+O4 yellow and Mn3+O5-6 violet chromophores. Zn2.9Mn0.1TeO6 is intense bright yellow, comparable with commercial BiVO4, and has better near-infrared reflectivity (∼89%) in comparison to commercial TiO2. The codoped Li+ "activator" generates holes and charge-balanced Mn3+ (Mn3+O5-6), realizing a color transformation from yellow to the bright violet pigments of A3-2xMnxLixTeO6. The most vivid Mg2.8Mn0.1Li0.1TeO6 is probably the best violet pigment known to date, exhibits excellent chemical and thermodynamic stability, and demonstrates pressure-dependent stability up to 5-7 GPa, before a (reversible) phase transition to pink. Theoretical calculations revealed the correlation between site-preference occupancy and chromophore motifs and predicted a wide color gamut of pigments in Zn3TeO6-hosted 3d transition-metal ions other than manganese.

6.
J Am Chem Soc ; 142(15): 7168-7178, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32216316

RESUMO

Understanding the electric dipole switching in multiferroic materials requires deep insight of the atomic-scale local structure evolution to reveal the ferroelectric mechanism, which remains unclear and lacks a solid experimental indicator in high-pressure prepared LiNbO3-type polar magnets. Here, we report the discovery of Zn-ion splitting in LiNbO3-type Zn2FeNbO6 established by multiple diffraction techniques. The coexistence of a high-temperature paraelectric-like phase in the polar Zn2FeNbO6 lattice motivated us to revisit other high-pressure prepared LiNbO3-type A2BB'O6 compounds. The A-site atomic splitting (∼1.0-1.2 Šbetween the split-atom pair) in B/B'-mixed Zn2FeTaO6 and O/N-mixed ZnTaO2N is verified by both powder X-ray diffraction structural refinements and high angle annular dark field scanning transmission electron microscopy images, but is absent in single-B-site ZnSnO3. Theoretical calculations are in good agreement with experimental results and suggest that this kind of A-site splitting also exists in the B-site mixed Mn-analogues, Mn2FeMO6 (M = Nb, Ta) and anion-mixed MnTaO2N, where the smaller A-site splitting (∼0.2 Šatomic displacement) is attributed to magnetic interactions and bonding between A and B cations. These findings reveal universal A-site splitting in LiNbO3-type structures with mixed multivalent B/B', or anionic sites, and the splitting-atomic displacement can be strongly suppressed by magnetic interactions and/or hybridization of valence bands between d electrons of the A- and B-site cations.

7.
J Vasc Surg ; 72(2): 651-657.e4, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31882310

RESUMO

OBJECTIVE: Lingual arteriovenous malformations (AVMs) are extremely rare in clinical practice, which has limited comprehensive research to find standard treatment protocols. This study summarizes the clinical features of lingual AVMs and assesses the safety and efficacy of ethanol embolotherapy in the management of these lesions. METHODS: Our study group was composed of 52 patients with lingual AVMs treated by ethanol embolization, all of whom received general anesthesia. The optimal access to the nidus of the AVM was by direct puncture, transarterial catheterization, transvenous catheterization, and a combination of these routes. Pure ethanol was manually injected into the nidus of the AVMs. The observed major or minor complications related to ethanol embolization were analyzed, and periodic follow-up of the patients was performed. The devascularization of the lingual AVMs between baseline and final angiography and the clinical outcomes of symptoms and signs after ethanol embolization were evaluated. RESULTS: There were 171 embolization procedures (mean, 3.3; range, 1-20) including 166 ethanol embolizations performed; the average volume of ethanol injected in a single ethanol embolization session was 29.8 mL (range, 1-65 mL). Therapeutic outcomes were complete response in 17 patients (33%), partial response in 33 patients (63%), and no response in 2 patients (4%). The effective therapeutic outcomes were gained in 96% of the patients with lingual AVMs treated with ethanol embolization; 25 (48%) of the patients had 83 complications, which were necrosis, infection, hemorrhage of the puncture point, transient hemoglobinuria, postoperative irritability, airway constriction, and coil migration, occurring in 78 procedures (46%). Regular follow-up of all the patients was performed, with the average follow-up period of 37.9 months (range, 1-125 months) after the last treatment. CONCLUSIONS: Ethanol embolization of lingual AVMs is safe and efficacious and is recommended to be the potential preferred method in the treatment of these complicated lesions.


Assuntos
Malformações Arteriovenosas/terapia , Embolização Terapêutica , Etanol/administração & dosagem , Boca/irrigação sanguínea , Adolescente , Adulto , Malformações Arteriovenosas/diagnóstico por imagem , Criança , Pré-Escolar , Embolização Terapêutica/efeitos adversos , Etanol/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
8.
J Vasc Interv Radiol ; 30(6): 813-821, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31060770

RESUMO

PURPOSE: The purpose of this study was to evaluate the management, outcomes, and technical and clinical safety of coil-assisted dominant outflow vein (DOV) occlusion for the ethanol embolization of high-flow arteriovenous malformations (AVMs) in the hands. MATERIALS AND METHODS: Between March 2013 and October 2016, 12 consecutive patients with AVMs with DOVs underwent ethanol embolization combined with detachable and pushable coil-assisted DOV occlusion. All patients completed the course of clinical follow-up (range: 14-57 months; mean: 36.7 months), and imaging follow-up (range: 8-25 months; mean: 16.6 months) results from the final treatment session were available for 8 patients. The therapeutic effects, degree of devascularization, and complications at the time of follow-up arteriography were evaluated as the clinical outcomes. RESULTS: The patients underwent 23 ethanol embolization procedures (range: 1-3; mean, 1.9) with 24 detachable coils and 223 pushable coils. The average stretched length of the total coils per patient was 320.17 cm. Seven of 12 patients (58.3%) exhibited complete responses, and 5 patients (41.7%) exhibited partial responses. Minor complications, including blistering and focal swelling, occurred in all 12 patients (100%) but showed spontaneous and complete recovery. No major complications occurred. CONCLUSIONS: Ethanol embolization has the potential to control high-flow hand AVMs by using coil-assisted DOV occlusion with an acceptable risk of minor and major complications.


Assuntos
Malformações Arteriovenosas/terapia , Embolização Terapêutica/instrumentação , Etanol/administração & dosagem , Mãos/irrigação sanguínea , Veias/fisiopatologia , Adolescente , Adulto , Malformações Arteriovenosas/diagnóstico por imagem , Malformações Arteriovenosas/fisiopatologia , Velocidade do Fluxo Sanguíneo , Criança , Embolização Terapêutica/efeitos adversos , Desenho de Equipamento , Etanol/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Veias/anormalidades , Veias/diagnóstico por imagem , Adulto Jovem
9.
Inorg Chem ; 58(15): 10280-10286, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31342741

RESUMO

A quadruple perovskite LaMn3Rh4O12 with A' = Mn and B = 4d transition metal was synthesized at high pressure (8 GPa) and temperature (1423 K) for the first time. Room temperature powder X-ray diffraction indicates that LaMn3Rh4O12 forms in cubic symmetry (Im3̅, a = 7.4997(1) Å). X-ray absorption near-edge spectroscopy shows predominantly Mn3+ and Rh3+ oxidation states. An antiferromagnetic transition at TN ∼ 41 K is corroborated by specific heat measurements. The resistivity measurements indicate a three-dimensional Mott variable-range hopping conduction mechanism between 300 and 160 K.

10.
Inorg Chem ; 58(20): 14193-14203, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31584269

RESUMO

Topotactic reduction of the perovskite oxide TbBaCo2O5.5 with CaH2 leads to a new crystalline phase TbBaCo2O4.5, adopting a 2 × 2 × 1 superstructure compared to TbBaCo2O5.5. The structure consists of a corner-shared network of square pyramidal CoO5 and trigonal planar CoO3 units. Magnetic susceptibility and variable temperature neutron diffraction data reveal that TbBaCo2O4.5 adopts a G-type antiferromagnetically ordered structure (TN ∼ 322 K). The ordered moments are consistent with the presence of low-spin Co2+ (S = 1/2) in trigonal-planar coordination and high-spin Co2+ centers in square pyramidal coordination. TbBaCo2O4.5 shows lower conductivity than TbBaCo2O5.5, which is consistent with the p-type conduction behavior. The unique anion vacancy arrangements in TbBaCo2O4.5 further complement the role of A-cations in controlling the oxygen vacancy distribution in LnBaCo2O5+δ series and demonstrate more opportunity to tune the structural and physical properties based on cationic and anionic lattice coupling.

11.
Inorg Chem ; 58(2): 1599-1606, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30608645

RESUMO

Li2GeTeO6 prepared at ambient pressure adopts the corundum derivative ordered ilmenite structure (rhombohedral R3). When heated at 1073 K and 3-5 GPa, the as-made Li2GeTeO6 can convert into a LiSbO3-derived Li2TiTeO6-type phase (orthorhombic Pnn2), which is the third LiSbO3-derived double A2BB'O6 phase in addition to Li2TiTeO6 and Li2SnTeO6. This Pnn2 Li2GeTeO6 phase spontaneously reverts to the R3 phase if annealed up to 1023 K at ambient pressure. Although the crystal structural analyses and second harmonic generation measurements clearly demonstrate the polar nature of both the R3 and Pnn2 phases, P( E) and dielectric measurements do not show any convincing ferroelectric response. Given the large estimated spontaneous polarization (17 and 80 µC/cm2), the absence of ferroelectric behavior could be attributed to the random domain distribution and leakage due to Li-ion migration.

12.
J Vasc Interv Radiol ; 29(3): 312-319, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29295765

RESUMO

PURPOSE: To assess treatment methods, interim results, and complications of absolute ethanol embolization combined with surgical resection of scalp arteriovenous malformations (AVMs). MATERIALS AND METHODS: From September 2012 to January 2015, 15 consecutive patients (8 male and 7 female) with scalp AVMs underwent staged ethanol embolizations. Ethanol embolization was performed using transcatheter and/or direct puncture techniques. Ten patients with scalp AVMs with a dominant outflow vein (DOV) also underwent coil deployment before ethanol embolization. Two patients underwent surgical resection after ethanol embolization was achieved. Follow-up evaluations included clinical outcome of symptoms and signs and imaging at 1.5 months, 6 months, and annually thereafter. RESULTS: In 15 patients, 33 ethanol embolizations were performed; 16 coil deployments were performed in 10 patients who had scalp AVMs with a DOV. Of 15 patients, 8 (53.3%) were cured, 2 of whom underwent surgical resection. All 8 patients showed no recurrence in the follow-up period (range, 12-48 months; mean, 25 months). Seven patients (46.7%) had partial remission and will need further treatment sessions for residual AVMs (range, 1-12 months; mean, 7 months). In 3 of 15 patients (20%), 7 minor complications (skin blisters and necrosis) occurred. All minor complications healed with wound dressing and observation. There were no major complications. CONCLUSIONS: Ethanol embolization has the potential for cure in management of scalp AVMs, with an acceptable risk of minor and major complications. Once AVMs are devascularized, surgical resection can be performed to improve cosmetic results.


Assuntos
Malformações Arteriovenosas/terapia , Embolização Terapêutica/métodos , Etanol/administração & dosagem , Couro Cabeludo/irrigação sanguínea , Adolescente , Adulto , Malformações Arteriovenosas/cirurgia , Criança , Terapia Combinada , Feminino , Humanos , Masculino , Resultado do Tratamento
13.
J Vasc Surg ; 61(4): 920-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25498162

RESUMO

OBJECTIVE: The purpose of this study was to review a single-institution contemporary experience with embolization treatment of pseudoaneurysms (PAs) from the external carotid artery (ECA). METHODS: From December 2000 to June 2014, PAs in the head and neck of 17 patients underwent embolization treatment and were retrospectively evaluated. All were treated with obliteration of the feeding artery or the PA by detachable coils or fibered coils, or both. Clinical follow-up was a mean of 91.9 months (range, 4-173 months) and was performed for all patients. Therapeutic outcomes were determined by evaluating the postprocedural image and clinical outcome of symptoms and signs. RESULTS: The 17 consecutive patients with head and neck PAs who underwent coils embolization treatment consisted of 14 male patients (82.3%) and three female patients (17.7%). The average age was 37.5 years (range, 16-57 years). The most common symptom and sign was a pulsatile mass, seen in 15 of 17 patients, and other symptoms included pain (three patients) or bleeding (four patients). Digital substraction angiography revealed that the PAs originated from the ECA in 3 patients and others originated from the branches of the ECA, including the superficial temporal artery in 6 patients, internal maxillary artery in 4, superior thyroid artery in 2, and the facial artery and posterior auricular artery in 1. Seventeen coils embolizations for occlusion of the parent artery were performed in 14 patients with a transarterial approach and in three by direct percutaneous puncture. All patients remained symptom free, and no procedure-related complications occurred. CONCLUSIONS: Embolization treatment of PAs from the ECA is a useful alternative to standard surgical repair. This modality avoids the necessity for surgical exposure of the face and of the neck with its inherent morbidity.


Assuntos
Falso Aneurisma/terapia , Doenças das Artérias Carótidas/terapia , Artéria Carótida Externa , Embolização Terapêutica , Adolescente , Adulto , Falso Aneurisma/diagnóstico , Angiografia Digital , Doenças das Artérias Carótidas/diagnóstico , Artéria Carótida Externa/diagnóstico por imagem , China , Embolização Terapêutica/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Punções , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
14.
J Craniofac Surg ; 26(2): 456-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25668118

RESUMO

Aneurysmal bone cysts (ABCs) rarely occur in the cranial bone. Surgical resection can lead to bone defects, deformities, functional abnormalities, and so on. This article describes a frontal ABC in a 73-year-old man who has a rapidly increasing swelling in the frontal bone preceded by an accidental trauma. In this case, we use percutaneous sclerotherapy with absolute alcohol under the guidance of fluoroscopy to treat the ABC instead of traditional surgical resection. When analyzed the follow-up imaging, bone reconstruction happened after using absolute alcohol. It is a feasible alternative treatment for ABC arising from the cranial bone.


Assuntos
Cistos Ósseos Aneurismáticos/terapia , Etanol/uso terapêutico , Osso Frontal/patologia , Soluções Esclerosantes/uso terapêutico , Escleroterapia/métodos , Idoso , Líquido Cístico/citologia , Eritrócitos/patologia , Estudos de Viabilidade , Fluoroscopia/métodos , Seguimentos , Osso Frontal/lesões , Humanos , Leucócitos/patologia , Masculino , Osteoclastos/patologia , Resultado do Tratamento
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124316, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38669982

RESUMO

Lysosomes, as crucial acidic organelles in cells, play a significant role in cellular functions. The levels and distribution of hypochlorous acid (HOCl) within lysosomes can profoundly impact their biological functionality. Hence, real-time monitoring of the concentration of HOCl in lysosomes holds paramount importance for further understanding various physiological and pathological processes associated with lysosomes. In this study, we developed a bodipy-based fluorescent probe derived from pyridine and phenyl selenide for the specific detection of HOCl in aqueous solutions. Leveraging the probe's sensitive photoinduced electron transfer effect from phenyl selenide to the fluorophore, the probe exhibited satisfactory high sensitivity (with a limit of detection of 5.2 nM and a response time of 15 s) to hypochlorous acid. Further biological experiments confirmed that the introduction of the pyridine moiety enabled the probe molecule to selectively target lysosomes. Moreover, the probe successfully facilitated real-time monitoring of HOCl in cell models stimulated by N-acetylcysteine (NAC) and lipopolysaccharide (LPS), as well as in a normal zebrafish model. This provides a universal method for dynamically sensing HOCl in lysosomes.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Lisossomos , Imagem Óptica , Peixe-Zebra , Ácido Hipocloroso/análise , Ácido Hipocloroso/metabolismo , Lisossomos/metabolismo , Lisossomos/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Animais , Humanos , Células RAW 264.7 , Camundongos , Compostos de Boro/química , Espectrometria de Fluorescência , Piridinas/química , Limite de Detecção
16.
Vet Microbiol ; 293: 110095, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38643723

RESUMO

Porcine epidemic diarrhea virus (PEDV) envelope protein (E) has been characterized as an important structural protein that plays critical roles in the interplay with its host to affect the virus life cycle. Stress granules (SGs) are host translationally silent ribonucleoproteins, which are mainly induced by the phosphorylation of eIF2α in the PERK/eIF2α signaling pathway. Our previous study found that PEDV E protein caused endoplasmic reticulum stress response (ERS)-mediated suppression of antiviral proteins' translation. However, the link and the underlying mechanism by which PEDV induces SGs formation and suppresses host translation remain elusive. In this study, our results showed that PEDV E protein significantly elevated the expression of GRP78, CANX, and phosphorylation of PERK and eIF2α, indicating that the PERK/eIF2α branch of ERS was activated. PEDV E protein localized to the ER and aggregated into puncta to reconstruct ER structure, and further induced SGs formation, which has been caused through upregulating the G3BP1 expression level. In addition, a significant global translational stall and endogenous protein translation attenuation were detected in the presence of E protein overexpression, but the global mRNA transcriptional level remained unchanged, suggesting that the shutoff of protein translation was associated with the translation, not with the transcription process. Collectively, this study demonstrates that PERK/eIF2α activation is required for SGs formation and protein translation stall. This study is beneficial for us to better understand the mechanism by which PEDV E suppresses host protein synthesis, and provides us a new insight into the host translation regulation during virus infection.


Assuntos
Fator de Iniciação 2 em Eucariotos , Vírus da Diarreia Epidêmica Suína , Biossíntese de Proteínas , Transdução de Sinais , Grânulos de Estresse , eIF-2 Quinase , Vírus da Diarreia Epidêmica Suína/fisiologia , Animais , eIF-2 Quinase/metabolismo , eIF-2 Quinase/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Suínos , Células Vero , Grânulos de Estresse/metabolismo , Grânulos de Estresse/genética , Chlorocebus aethiops , Chaperona BiP do Retículo Endoplasmático/metabolismo , Fosforilação , Estresse do Retículo Endoplasmático
17.
Mater Horiz ; 11(11): 2749-2758, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38533828

RESUMO

The intricate correlation between lattice geometry, topological behavior and charge degrees of freedom plays a key role in determining the physical and chemical properties of a quantum-magnetic system. Herein, we investigate the introduction of the unusual oxidation state as an alternative pathway to modulate the magnetic ground state in the well-known S = 1 Haldane system nickelate Y2BaNiO5 (YBNO). YBNO is topologically reduced to incorporate d9-Ni+ (S = 1/2) in the one-dimensional Haldane chain system. The random distribution of Ni+ for the first time results in the emergence of a one-dimensional ferromagnetic phase with a transition temperature far above room temperature. Theoretical calculations reveal that the antiferromagnetic interplay can evolve into ferromagnetic interactions with the presence of oxygen vacancies, which promotes the formation of ferromagnetic order within one-dimensional nickel chains. The unusual electronic instabilities in the nickel-based Haldane system may offer new possibilities towards unconventional physical and chemical properties from quantum interactions.

18.
Mil Med Res ; 11(1): 39, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902798

RESUMO

BACKGROUND: Despite the efficacy of absolute ethanol (EtOH), its radiolucency introduces several risks in interventional therapy for treating vascular malformations. This study aims to develop a novel radiopaque ethanol injection (REI) to address this issue. METHODS: Iopromide is mixed with ethanol to achieve radiopacity and improve the physicochemical properties of the solution. Overall, 82 male New Zealand white rabbits are selected for in vivo radiopacity testing, peripheral vein sclerosis [animals were divided into the following 5 groups (n = 6): negative control (NC, saline, 0.250 ml/kg), positive control (EtOH, 0.250 ml/kg), low-dose REI (L-D REI, 0.125 ml/kg), moderate-dose REI (M-D REI, 0.250 ml/kg), and high-dose REI (H-D REI 0.375 ml/kg)], pharmacokinetic analyses (the blood sample was harvested before injection, 5 min, 10 min, 20 min, 40 min, 1 h, 2 h, 4 h, and 8 h after injection in peripheral vein sclerosis experiment), peripheral artery embolization [animals were divided into the following 5 groups (n = 3): NC (saline, 0.250 ml/kg), positive control (EtOH, 0.250 ml/kg), L-D REI (0.125 ml/kg), M-D REI (0.250 ml/kg), and H-D REI (0.375 ml/kg)], kidney transcatheter arterial embolization [animals were divided into the following 4 groups (n = 3): positive control (EtOH, 0.250 ml/kg), L-D REI (0.125 ml/kg), M-D REI (0.250 ml/kg), and H-D REI (0.375 ml/kg); each healthy kidney was injected with saline as negative control], and biosafety evaluations [animals were divided into the following 5 groups (n = 3): NC (0.250 ml/kg), high-dose EtOH (0.375 ml/kg), L-D REI (0.125 ml/kg), M-D REI (0.250 ml/kg), and H-D REI (0.375 ml/kg)]. Then, a prospective cohort study involving 6 patients with peripheral venous malformations (VMs) is performed to explore the clinical safety and effectiveness of REI. From Jun 1, 2023 to August 31, 2023, 6 patients [age: (33.3 ± 17.2) years] with lingual VMs received sclerotherapy of REI and 2-month follow-up. Adverse events and serious adverse events were evaluated, whereas the efficacy of REI was determined by both the traceability of the REI under DSA throughout the entire injection and the therapeutic effect 2 months after a single injection. RESULTS: The REI contains 81.4% ethanol (v/v) and 111.3 mg/ml iodine, which can be traced throughout the injection in the animals and patients. The REI also exerts a similar effect as EtOH on peripheral venous sclerosis, peripheral arterial embolization, and renal embolization. Furthermore, the REI can be metabolized at a similar rate compared to EtOH and Ultravist® and did not cause injury to the animals' heart, liver, spleen, lungs, kidneys and brain. No REI-related adverse effects have occurred during sclerotherapy of VMs, and 4/6 patients (66.7%) have achieved complete response at follow-up. CONCLUSION: In conclusion, REI is safe, exerts therapeutic effects, and compensates for the radiolucency of EtOH in treating VMs. TRIAL REGISTRATION: The clinical trial was registered as No. ChiCTR2300071751 on May 24 2023.


Assuntos
Etanol , Malformações Vasculares , Animais , Coelhos , Etanol/uso terapêutico , Etanol/farmacologia , Masculino , Malformações Vasculares/terapia , Malformações Vasculares/tratamento farmacológico , Humanos , Meios de Contraste/farmacocinética , Meios de Contraste/farmacologia , Meios de Contraste/uso terapêutico , Iohexol/análogos & derivados
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 303: 123284, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37619488

RESUMO

Phosgene is an important and widely used highly toxic chemical that poses a serious potential threat to public health and property if leaked or abused. Therefore, developing an efficient and convenient detection method for phosgene is of great significance. In this work, we synthesized a novel fluorescent probe, BCyP, based on benzohemicyanine for highly selective and sensitive detection of phosgene in both liquid and gas phases. The probe uses amino alcohol as a specific recognition group for phosgene and does not fluoresce due to the strong intramolecular charge transfer effect (ICT). However, in the presence of phosgene, the amino alcohol part in the probe can form oxazolidinone in situ with phosgene, reducing the ICT effect in the probe molecule and lighting fluorescence, thus realizing the selective phosgene detection. The probe exhibits good specificity towards phosgene, with significant fluorescence enhancement (approximately 400-fold), a remarkable Stokes shift (139 nm), a fast response speed (less than 17 s), and a low detection limit (0.12 ppm). Additionally, we prepared a phosgene detection paper strip loaded with the probe on filter paper and combined it with color recognition software on a smartphone to achieve visual detection of phosgene in the gas phase.

20.
Talanta ; 265: 124912, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37451118

RESUMO

Leakage and misuse of phosgene, a common and highly hazardous industrial chemical, have always constituted a safety risk. Therefore, it is crucial to develop sensitive detection methods for gaseous phosgene. This work describes the design and development of a new fluorescent dye based on benzohemicyanine, as well as the synthesis of fluorescent probes for the sensitive detection of gaseous phosgene. Due to the excellent intramolecular charge transfer (ICT) effect from the strong electron-donating impact of the o-aminophenol group on benzo hemicyanine, the probe does not emit fluorescence. When the probe reacts with phosgene, the ICT effect is inhibited, and the result exhibits observable green fluorescence, thereby visualizing the response to phosgene. The probe offers exceptional sensitivity, a rapid response, and a low phosgene detection limit. In addition, we developed probe-loaded, portable test strips for the quick and sensitive detection of phosgene in the gas phase. Finally, the constructed probe-loaded test strips were utilized effectively to monitor the simulated phosgene leakage.

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