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1.
Chemistry ; : e202402679, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39298687

RESUMO

The triplet excited state lifetime of a photosensitizer is an essential parameter for diffusion-controlled energy- and electron-transfer, which occurs usually in a competitive manner to the intrinsic decay of a triplet excited state. Here we show the decisive role of luminescence lifetime in the triplet excited state reactivity toward energy- and electron transfer. Anchoring two phenyl anthracene chromophores to a ruthenium(II) polypyridyl complex (RuII ref) leads to a RuII triad with a luminescence lifetime above 100 µs, which is more than 40 times longer than that of the prototypical complex. The obtained RuII triad sensitizes energy transfer to anthracene-based annihilators more efficiently than the RuII ref and enables red-to-blue photon upconversion with a pseudo anti-Stokes shift of 0.94 eV and a moderate upconversion efficiency near 1% in aerated solution. Particularly, the RuII triad allows rapid photoredox catalytic polymerizations of acrylate and acrylamide monomers under aerobic condition with red light, which are kinetically hindered for the RuII ref. Our work shows that excited state lifetime of a photosensitizer governs the dynamics of the excited state reactions, which seems an overlooked but important aspect for photochemistry.

2.
Artigo em Inglês | MEDLINE | ID: mdl-37126199

RESUMO

Primary angiitis of the central nervous system (PACNS) is a rare and fatal cerebral vasculitis mainly involving the arteriole of the pia mater, cerebral cortex, and spinal cord. It has an insidious onset atypical symptoms. In this paper, we reported an unexpected death due to cerebral hemorrhage caused by PACNS. According to the typical clinical manifestations (headache, dizziness, weakness of the limbs, temporary blurred vision, etc.) and pathological examination (wide degeneration and fibrinoid necrosis of blood vessel walls with inflammatory cell infiltration), as well as hematoxylin-eosin staining, immunohistochemistry for CD15 + and gram staining, we finally determined that the patient died due to cerebral vascular rupture and hemorrhage caused by PACNS. This case illustrates the value and key points of autopsy in evaluating sudden deaths.

3.
J Org Chem ; 87(3): 1679-1688, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-34743518

RESUMO

Catalytic enantiodifferentiating photoisomerization of cyclooctene (1Z) included and sensitized by regioisomeric 6-O-(o-, m-, and p-methoxybenzoyl)-ß-cyclodextrins (CDs) was performed under a variety of solvent conditions for higher enantioselectivities. The enantiomeric excess (ee) of chiral (E)-isomer (1E) produced was a critical function of all the internal and external factors examined, in particular, the sensitizer structure and the solvent conditions, to afford (R)-1E in record-high ee's of up to 67% upon sensitization with the meta-substituted ß-CD host in water and salt solutions but neither in 50% aqueous ethanol nor with the ortho- and para-substituted hosts. The mechanistic origin of the sudden ee enhancement achieved under the specific conditions is discussed on the basis of the circular dichroism spectral behaviors upon substrate inclusion and the compensatory enthalpy-entropy relationship of the activation parameters for the enantiodifferentiating photoisomerization.


Assuntos
beta-Ciclodextrinas , Ciclo-Octanos/química , Conformação Molecular , Fotoquímica , Solventes/química , beta-Ciclodextrinas/química
4.
Analyst ; 147(5): 880-888, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35137747

RESUMO

Palladium@gold nanoparticle modified three-dimensional-reduced graphene oxide (3D-rGO/Pd@Au) was coupled with carboxymethyl-ß-cyclodextrin to form a novel nanocomposite (3D-rGO/Pd@Au/CM-ß-CD). The 3D-rGO/Pd@Au/CM-ß-CD served as a chiral sensing interface for the electrochemical enantiorecognition of tyrosine (Tyr) via a differential pulse voltammetry (DPV) approach. The 3D-rGO/Pd@Au demonstrates good electrical conductivity and efficient catalytic activity as an electrochemical indicator. Simultaneously, the CM-ß-CD displays a supramolecular chiral selectivity to reveal a higher binding affinity to the target L-tyrosine (L-Tyr) than to D-tyrosine (D-Tyr). Under the optimized determining conditions, the oxidation peak current ratio of L-Tyr to D-Tyr (IL/ID) was 2.12, meanwhile, the peak currents of the two isomers were linearly proportional to the concentration over the range of 0.8-130 µM with LODs of 52 nM and 96 nM for L- and D-Tyr (S/N = 3), respectively. This approach exhibits distinguished sensitivity, excellent selectivity and good reproducibility, as well as great stability, which can accurately determine the relative content of L- or D-Tyr enantiomers in a racemic solution.


Assuntos
Grafite , Nanopartículas Metálicas , Nanocompostos , Técnicas Eletroquímicas , Ouro/química , Grafite/química , Nanopartículas Metálicas/química , Nanocompostos/química , Reprodutibilidade dos Testes , Tirosina/química , beta-Ciclodextrinas
5.
Cardiovasc Toxicol ; 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39153146

RESUMO

In this study, by pooling the clinical data of patients who died with a history of long-term clozapine use and by examining their hearts, it was found that long-term clozapine use can lead to cardiomyopathy and that its presentation resembles arrhythmogenic cardiomyopathy (ACM), i.e., it exhibits a predominantly right ventricular fatty infiltration with mild left ventricular damage. The transcriptomic data of rat cardiomyocytes after clozapine intervention were analyzed by transcriptomic approach to explore the causes of clozapine cardiomyopathy. The cause of clozapine cardiomyopathy was then explored by a transcriptomic approach, which revealed that its clozapine action on cardiomyocytes enriched cardiomyocyte-related differential genes in biological processes such as muscle development and response to hypoxia, as well as pathways such as fatty acid metabolism and cellular autophagy. Transcriptomic analysis showed that Egr1, Egr2, ler2, Jun, Mapk9, Nr1d2, Atf3, Bhlhe40, Crem, Cry1, Cry2, Dbp were hub genes for clozapine injury to the myocardium, and that these genes may play an important role in the myocardial ACM-like changes caused by clozapine. Combined with the results of pathological examination and transcriptomic analysis, it can be concluded that the long-term action of clozapine on cardiomyocytes leads to cellular autophagy and subsequent structural remodeling of the heart, and in the remodeling affects fatty acid metabolism, which eventually leads to ACM-like changes.

6.
Anal Methods ; 15(30): 3642-3649, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37475678

RESUMO

Ractopamine (RAC) is universally known for improving lean meat percentage in livestock and thus is widely introduced as a feed additive. However, it is difficult to eliminate the RAC residue in animal tissues from the biological system and will inevitably harm human health. Hence, detecting RAC molecules in biological samples is extremely significant. Herein, a novel strategy of supramolecular recognition-enhanced electrochemical sensing is presented. This platform was constructed by coupling ß-cyclodextrin (ß-CD) with palladium nanoparticles (Pd NPs)-functionalized three-dimensional reduced graphene oxide (3D-rGO) to form a nanocomposite (3D-rGO/Pd/ß-CD), which was further used to modify a glassy carbon electrode (GCE) for RAC detection. Benefiting from the attractive electrical conductivity and catalytic activity of 3D-rGO/Pd, as well as the unique small-molecule-recognition ability of ß-CD demonstrated by 1H NMR spectrum, which revealed the 1 : 2 binding mode of RAC with ß-CD, increased peak current signals of RAC were observed in the cyclic voltammetry (CV) test. Under optimized conditions, the wide linear concentration range spanned 1-95 µM, along with a relatively low detection limit of 0.12 µM (S/N = 3), as evidenced by the differential pulse voltammetry (DPV) approach. The platform also exhibited satisfactory stability and fine reproducibility, as well as high selectivity and good anti-interference capability. Moreover, this as-obtained sensor was efficiently applied in pork samples with a high recovery rate (96.44-103.99%), which provides a promising view of its electrochemical biosensing ability in practical applications.


Assuntos
Nanopartículas Metálicas , Nanocompostos , beta-Ciclodextrinas , Animais , Humanos , Carbono/química , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Técnicas Eletroquímicas/métodos , Paládio/química , Eletrodos , Nanocompostos/química
7.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 40(6): 441-4, 2005 Nov.
Artigo em Zh | MEDLINE | ID: mdl-16329820

RESUMO

OBJECTIVE: To determine the long-term clinical outcome and predictability of the maxillary sinus augmentation procedure. METHODS: Seventy-four patients underwent 100 sinus bone graft procedure and 206 implants were placed. The patients were followed up for 1-9 years, with an average of 3.46 +/- 1.65 years after implant placement. RESULTS: The 5-year cumulative survival rate (CSR) of implants was 92.28%. Only 8 implants failed and no sinusitis occurred. CONCLUSIONS: Sinus bone graft is an adjunctive procedure with a predictable outcome in patients with severely atrophied posterior maxilla.


Assuntos
Transplante Ósseo/métodos , Implantação Dentária Endóssea/métodos , Seio Maxilar/cirurgia , Adolescente , Adulto , Idoso , Substitutos Ósseos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
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