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1.
Medicine (Baltimore) ; 102(38): e34660, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37747026

RESUMEN

BACKGROUND: There is currently no uniform and effective treatment for patients with locally advanced oral cancer who cannot tolerate surgery or radiotherapy. The prognosis of oral cancer patients with lymph node metastasis is very poor, but the clinical treatment of such patients faces certain challenges. PATIENTS AND METHODS: Case 1 was a 59-year-old patient with tongue cancer (cT 3 N x M 0 G 2) who refused radiotherapy because of a history of leukoderma. After evaluation of disease condition, a 4-drug combination therapy of toripalimab + anlotinib + nabpaclitaxel + carboplatin was administered. Case 2 was a 55-year-old patient with tongue cancer (cT 3 N 2 M 0 G 1) who could not receive radiotherapy because of a medical history of cervicofacial burns. After disease evaluation, toripalimab + anlotinib + docetaxel + carboplatin combination therapy was administered. CASE SUMMARY: Both patients did not experience any adverse reactions during treatment and achieved a complete response after 2 cycles of treatment. Their progression-free survival is currently 6 and 8 months, respectively, and they are in sustained remission. CONCLUSION: Currently, the efficacy of immune checkpoint inhibitors targeting programmed death-1 as a first-line treatment of inoperable and non-radiatable locally advanced oral cancer is unknown. Here, we describe 2 cases of locally advanced oral cancer treated with first-line immune checkpoint inhibitors in combination with targeted therapy and chemotherapy. This approach was successful in these patients, but a larger sample size is required to verify our findings.


Asunto(s)
Neoplasias de la Boca , Neoplasias de la Lengua , Humanos , Persona de Mediana Edad , Neoplasias de la Lengua/tratamiento farmacológico , Carboplatino/uso terapéutico , Inhibidores de Puntos de Control Inmunológico , Inmunización
2.
Adv Sci (Weinh) ; 9(33): e2204382, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36202749

RESUMEN

The ability to control the mobility and function of droplets is fundamental to developing open surface microfluidics. Despite notable progress in the manipulation of droplets, the existing strategies are still limited in functionalizing droplets. Herein, the coupling of droplet motion and functionalization elicited by an invisible charge wall is reported. The charged superamphiphobic surface is overlapped with a conductor to induce free charge, creating the invisible charge wall at the overlapping boundary. The charge wall can trap droplets and polarize them into Janus charged state. It is found that the trapping degree and the charge distribution in the Janus charged droplet depend on the original surface charge on the superamphiphobic surface. The invisible charge wall can also be established at diverse boundary curvatures, allowing to design pathways for droplet manipulations. Furthermore, the enrichment of protein and nanomaterial in the manipulated Janus charged droplet is demonstrated. The strategy provides a potential microfluidic platform with orthogonal functionalities.


Asunto(s)
Microfluídica
3.
Front Plant Sci ; 13: 929532, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35874004

RESUMEN

The oxygen-evolving center (OEC) in photosystem II (PSII) of oxygenic photosynthetic organisms is a unique heterometallic-oxide Mn4CaO5-cluster that catalyzes water splitting into electrons, protons, and molecular oxygen through a five-state cycle (Sn, n = 0 ~ 4). It serves as the blueprint for the developing of the man-made water-splitting catalysts to generate solar fuel in artificial photosynthesis. Understanding the structure-function relationship of this natural catalyst is a great challenge and a long-standing issue, which is severely restricted by the lack of a precise chemical model for this heterometallic-oxide cluster. However, it is a great challenge for chemists to precisely mimic the OEC in a laboratory. Recently, significant advances have been achieved and a series of artificial Mn4XO4-clusters (X = Ca/Y/Gd) have been reported, which closely mimic both the geometric structure and the electronic structure, as well as the redox property of the OEC. These new advances provide a structurally well-defined molecular platform to study the structure-function relationship of the OEC and shed new light on the design of efficient catalysts for the water-splitting reaction in artificial photosynthesis.

4.
Chemistry ; 28(52): e202201456, 2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-35713343

RESUMEN

The oxygen-evolving center (OEC) in photosynthesis is a unique Mn4 CaO5 -cluster that catalyzes the water-splitting reaction in nature. Understanding its catalytic mechanism for the O=O bond formation is of great challenge and long-standing issue, which is severely restricted by the lack of precise structure and mechanism mimics of this heterometallic-oxide cluster. Herein, we report two synthetic (Mn3 XO4 )2 O-clusters (X=Sr2+ , La3+ ) that closely mimic the heterometallic-oxide Mn3 XO4 cubane and three different types of µ-oxide bridges (µ2 -O2- , µ3 -O2- , and µ4 -O2- ) simultaneously as seen in the OEC. By resolving the crystal structures of both oxidized and reduced forms of the cluster, we have identified significant redox-induced structural changes that take place on the µ2 -oxide bridge, rather than the µ4 -oxide or µ3 -oxide bridges. Our results provide chemical insights into understanding the reactivity of three different types of oxide bridges in the biological Mn4 CaO5 -cluster in PSII.


Asunto(s)
Óxidos , Oxígeno , Oxidación-Reducción , Óxidos/química , Oxígeno/química , Fotosíntesis , Complejo de Proteína del Fotosistema II/química , Complejo de Proteína del Fotosistema II/metabolismo , Agua/química
5.
ChemSusChem ; 15(6): e202102661, 2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35075776

RESUMEN

The photosynthetic oxygen-evolving center (OEC) is a unique Mn4 CaO5 cluster that serves as a blueprint to develop superior water-splitting catalysts for the generation of solar fuels in artificial photosynthesis. It is a great challenge and long-standing issue to reveal the synthesizing mechanism of this Mn4 CaO5 cluster in both natural and artificial photosynthesis. Herein, efforts were made to reveal the synthesizing mechanism of an artificial Mn4 CaO4 cluster, a close mimic of the OEC. Four key intermediates were successfully isolated and structurally characterized for the first time. It was demonstrated that the Mn4 CaO4 cluster could be formed through a reaction between a thermodynamically stable Mn3 CaO4 cluster and an unusual four-coordinated MnIII ion, followed by stabilization process through binding an organic base (e.g., pyridine) on the "dangling" Mn ion. These findings shed new light on the synthesizing mechanism of the OEC and rational design of new artificial water-splitting catalysts.


Asunto(s)
Oxígeno , Complejo de Proteína del Fotosistema II , Catálisis , Oxidación-Reducción , Oxígeno/química , Fotosíntesis , Complejo de Proteína del Fotosistema II/química , Agua/química
6.
J Am Chem Soc ; 143(42): 17360-17365, 2021 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-34643379

RESUMEN

The oxygen-evolving center (OEC) in photosynthesis is a unique biological Mn4CaO5 cluster catalyzing the water-splitting reaction. A great current challenge is to achieve a robust and precise mimic of the OEC in the laboratory. Herein, we report synthetic Mn4XO4 clusters (X = calcium, yttrium, gadolinium) that closely resemble the OEC with regard to the main metal-oxide core and peripheral ligands, as well as the oxidation states of the four Mn ions and the redox potential of the cluster. We demonstrate that rare-earth elements can structurally replace the calcium in neutral Mn4XO4 clusters. All three Mn4XO4 clusters with different redox-inactive metal ions display essentially the same redox properties, challenging the conventional view that the Lewis acidity of the redox-inactive metal ions could modulate the redox potential of the heteronuclear-oxide clusters. The new synthetic rare-earth element-containing Mn4XO4 clusters reported here provide robust and structurally well-defined chemical models and shed new light on the design of new water-splitting catalysts in artificial photosynthesis.


Asunto(s)
Materiales Biomiméticos/química , Calcio/química , Complejos de Coordinación/química , Gadolinio/química , Óxidos/química , Itrio/química , Estructura Molecular , Oxidación-Reducción , Complejo de Proteína del Fotosistema II/química
7.
ACS Appl Mater Interfaces ; 10(46): 39713-39722, 2018 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-30346126

RESUMEN

Fe2TiO5 was synthesized via the solvothermal method and adopted as co-catalyst to improve the photoelectrochemical (PEC) water splitting performance of BiVO4 photoanode. After surface modification by Fe2TiO5, the BiVO4/Fe2TiO5 photoanode shows a 300 mV cathodic shift in onset potential and 3 times enhancement in photocurrent, which delivers a photocurrent density of 3.2 mA/cm2 at 1.23 V vs reverse hydrogen electrode. Systematic optical, electrochemical, and intensity-modulated photocurrent spectroscopy characterizations were performed to explore the role of Fe2TiO5 and reveal that the enhanced PEC performance is mainly caused by the surface passivation effect of Fe2TiO5.

8.
Bosn J Basic Med Sci ; 18(4): 297-304, 2018 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-30179586

RESUMEN

Pancreatic cancer (PC) is a highly aggressive tumor, often difficult to diagnose and treat. Aspartate ß-hydroxylase (ASPH) is a type II transmembrane protein and the member of α-ketoglutarate-dependent dioxygenase family, found to be overexpressed in different cancer types, including PC. ASPH appears to be involved in the regulation of proliferation, invasion and metastasis of PC cells through multiple signaling pathways, suggesting its role as a tumor biomarker and therapeutic target. In this review, we briefly summarize the possible mechanisms of action of ASPH in PC and recent progress in the therapeutic approaches targeting ASPH.


Asunto(s)
Proteínas de Unión al Calcio/metabolismo , Proteínas de la Membrana/metabolismo , Oxigenasas de Función Mixta/metabolismo , Proteínas Musculares/metabolismo , Neoplasias Pancreáticas/enzimología , Animales , Antineoplásicos/farmacología , Proteínas de Unión al Calcio/análisis , Proteínas de Unión al Calcio/química , Humanos , Proteínas de la Membrana/análisis , Proteínas de la Membrana/química , Oxigenasas de Función Mixta/análisis , Oxigenasas de Función Mixta/química , Proteínas Musculares/análisis , Proteínas Musculares/química , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología
9.
Angew Chem Int Ed Engl ; 55(51): 15802-15806, 2016 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-27873434

RESUMEN

We describe the use of simple copper-salt catalysts in the selective aerobic oxidation of amines to nitriles or imines. These catalysts are marked by their exceptional efficiency, operate at ambient temperature and pressure, and allow the oxidation of amines without expensive ligands or additives. This study highlights the significant role counterions can play in controlling selectivity in catalytic aerobic oxidations.

10.
Angew Chem Int Ed Engl ; 54(14): 4208-11, 2015 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-25677693

RESUMEN

The copper-catalyzed aerobic oxidation of primary and secondary alcohols without an external N-oxide co-oxidant is described. The catalyst system is composed of a Cu/diamine complex inspired by the enzyme tyrosinase, along with dimethylaminopyridine (DMAP) or N-methylimidazole (NMI). The Cu catalyst system works without 2,2,6,6-tetramethyl-l-piperidinoxyl (TEMPO) at ambient pressure and temperature, and displays activity for un-activated secondary alcohols, which remain a challenging substrate for catalytic aerobic systems. Our work underscores the importance of finding alternative mechanistic pathways for alcohol oxidation, which complement Cu/TEMPO systems, and demonstrate, in this case, a preference for the oxidation of activated secondary over primary alcohols.


Asunto(s)
Alcoholes/química , Cobre/química , Óxidos N-Cíclicos/química , Aerobiosis , Catálisis
11.
Molecules ; 17(12): 13759-68, 2012 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-23174894

RESUMEN

We describe the palladium-catalyzed multicomponent synthesis of 2-imidazolines. This reaction proceeds via the coupling of imines, acid chlorides and carbon monoxide to form imidazolinium carboxylates, followed by a decarboxylation. Decarboxylation in CHCl(3) is found to result in a mixture of imidazolinium and imidazolium salts. However, the addition of benzoic acid suppresses aromatization, and generates the trans-disubstituted imidazolines in good yield. Combining this reaction with subsequent nitrogen deprotection provides an overall synthesis of imidazolines from multiple available building blocks.


Asunto(s)
Catálisis , Imidazoles , Iminas , Paladio/química , Monóxido de Carbono , Ácidos Carboxílicos , Cloruros/síntesis química , Cloruros/química , Descarboxilación , Imidazoles/síntesis química , Imidazoles/química , Iminas/síntesis química , Iminas/química , Estructura Molecular
12.
J Org Chem ; 76(1): 170-80, 2011 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-21142047

RESUMEN

A palladium-catalyzed multicomponent synthesis of imidazolinium carboxylates and imidazolines is described. The palladium catalyst [Pd(CH(R(1))N(R(2))COR(3))Cl](2), or [Pd(allyl)Cl](2), with P(t-Bu)(2)(2-biphenyl) can mediate the simultaneous coupling of two imines, acid chloride, and carbon monoxide into substituted imidazolinium carboxylates within hours under mild conditions (45 °C, 4 atm of CO). The reaction proceeds in good yield with aryl-, heteroaryl-, and alkyl-substituted acid chlorides, as well as variously functionalized imines. Imidazolines are formed via the initial generation of Münchnone intermediates, followed by their cycloaddition with an in situ generated protonated imine. The addition of an amine base can intercept catalysis at Münchnone formation, which allows the subsequent cycloaddition of a second imine. The latter provides a route for the assembly of complex, polysubstituted imidazolinium carboxylates with independent control of all five substituents. The subsequent removal of the nitrogen substituent(s) provides an overall synthesis of imidazolines.


Asunto(s)
Monóxido de Carbono/química , Ácido Clorhídrico/química , Imidazoles/síntesis química , Imidazolinas/síntesis química , Iminas/química , Paladio/química , Catálisis , Imidazoles/química , Imidazolinas/química , Espectroscopía de Resonancia Magnética , Estructura Molecular
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