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1.
Cancer Med ; 13(13): e7307, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38967137

RESUMEN

BACKGROUND: This study aims to investigate the early kinetics of interleukin 6 (IL-6), procalcitonin (PCT), and C-reactive protein (CRP) on initial antibiotic efficacy in hematological disorder patients with febrile neutropenia (FN). METHODS: A total of 40 patients with 43 episodes of FN were enrolled and divided into initial antibiotic effective group (IAE group, n = 24) and initial antibiotic ineffective group (IAI group, n = 19). The levels of IL-6, PCT, and CRP before antibacterial treatment (T0), and 12 h (T1), 24 h (T2), 48 h (T3), and 72 h (T4) post-antibacterial treatment were determined, respectively. Furthermore, the receiver operating characteristic curve (ROC) analysis was performed to evaluate the clinical value of indicators. RESULTS: In IAE group, the IL-6 levels gradually decreased from T0 to T4, and the CRP levels significantly decreased at 48 to 72 h, whereas both IL-6 and CRP remained at high levels in the IAI group. The PCT levels in both groups increased at the early stage of anti-infection (T1-T2) and reached to peak at T1-T2 in effective group. ROC curve analysis identified IL-6 as a predictive biomarker for initial antibiotic efficacy at 12, 48, and 72 h after treatment, with the AUC of 0.698, 0.744, and 0.821, respectively. In addition, CRP demonstrated predictive ability of initial antibiotics against infection at 24, 48, and 72 h after therapy, with the AUC of 0.724, 0.741, and 0.797, respectively. ROC curve analysis of percentage changes demonstrated that IL-6 percentage change showed predictive ability of antibiotic efficacy at the early stage, and both the IL-6 and CRP percentage changes showed the predictive ability of antibiotic efficacy 48 or 72 h after antibiotics therapy. CONCLUSION: This study confirmed IL-6 and CRP levels, and the percentage change in IL-6 as the biomarkers for initial antibiotic efficacy prediction in hematological disorder patients with FN.


Asunto(s)
Antibacterianos , Biomarcadores , Proteína C-Reactiva , Neutropenia Febril , Interleucina-6 , Polipéptido alfa Relacionado con Calcitonina , Humanos , Proteína C-Reactiva/análisis , Proteína C-Reactiva/metabolismo , Interleucina-6/sangre , Polipéptido alfa Relacionado con Calcitonina/sangre , Masculino , Femenino , Antibacterianos/uso terapéutico , Persona de Mediana Edad , Neutropenia Febril/tratamiento farmacológico , Neutropenia Febril/sangre , Estudios Prospectivos , Adulto , Biomarcadores/sangre , Curva ROC , Anciano , Resultado del Tratamiento
2.
Angew Chem Int Ed Engl ; : e202409387, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38925605

RESUMEN

Phosphine-ligated transition metal complexes play a pivotal role in modern catalysis, but our understanding of the impact of ligand counts on the catalysis performance of the metal center is limited. Here we report the synthesis of a low-coordinate mono(phosphine)-Rh catalyst on a metal-organic layer (MOL), P-MOL●Rh, and its applications in the hydrogenation of mono-, di-, and tri-substituted alkenes as well as aryl nitriles with turnover numbers (TONs) of up to 390000. Mechanistic investigations and density functional theory calculations revealed the lowering of reaction energy barriers by the low steric hindrance of site-isolated mono(phosphine)-Rh sites on the MOL to provide superior catalytic activity over homogeneous Rh catalysts. The MOL also prevents catalyst deactivation to enable recycle and reuse of P-MOL●Rh in catalytic hydrogenation reactions.

3.
J Steroid Biochem Mol Biol ; 240: 106498, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38447903

RESUMEN

Phytosterols are vital structural and regulatory components in plants. Zea mays produces a series of phytosterols that are specific to corn. However, the underline biosynthetic mechanism remains elusive. In this study, we identified a novel sterol methyltransferase from Z. mays (ZmSMT1-2) which showed a unique feature compared with documented plant SMTs. ZmSMT1-2 showed a substrate preference for cycloartenol. Using S-adenosyl-L-methionine (AdoMet) as a donor, ZmSMT1-2 converted cycloartenol into alkylated sterols with unique side-chain architectures, including Δ25(27) (i.e., cyclolaudenol and cycloneolitsol) and Δ24(25) (i.e., cyclobranol) sterols. Cycloneolitsol is identified as a product of SMTs for the first time. Our discovery provides a previously untapped mechanism for phytosterol biosynthesis and adds another layer of diversity of sterol biosynthesis.


Asunto(s)
Metiltransferasas , Fitosteroles , Triterpenos , Zea mays , Zea mays/metabolismo , Fitosteroles/metabolismo , Fitosteroles/química , Metiltransferasas/metabolismo , Metiltransferasas/química , Metiltransferasas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/química , Especificidad por Sustrato , S-Adenosilmetionina/metabolismo , S-Adenosilmetionina/química
4.
Acta Otolaryngol ; 143(7): 576-581, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37466376

RESUMEN

BACKGROUND: Few related studies reported yet the association between vitamins and the onset of sudden sensorineural hearing loss (SSNHL). OBJECTIVE: To explore the relationship between the serum levels of fat-soluble vitamins A, D, and E and the risk of SSNHL. METHODS: This retrospective analysis included 310 SSNHL patients and 154 people without risk of hearing loss. The demographic information of all participants like age, gender, body mass index, occupation, cigarette smoking or drinking status, etc. were recorded. The serum levels of vitamins A, D, and E were determined using the electrochemical method. RESULTS: The results indicated that serum vitamin D levels in SSNHL patients were significantly lower. Vitamin D deficiency was only observed in SSNHL group. Similarly, serum vitamin A levels in female SSNHL patients were significantly lower than the control group. Meanwhile, serum vitamin E levels in male SSNHL patients were significantly lower than the control group. CONCLUSION AND SIGNIFICANCE: Our results revealed that the serum levels of fat-soluble vitamins A, D, and E in SSNHL patients were lower than those in the control group with normal hearing, indicating that the decrease of serum fat-soluble vitamins may be related to SSNHL pathogenesis.


Asunto(s)
Pérdida Auditiva Sensorineural , Pérdida Auditiva Súbita , Humanos , Masculino , Femenino , Estudios Retrospectivos , Vitaminas , Pérdida Auditiva Súbita/etiología , Pruebas Auditivas , Vitamina A , Vitamina K
5.
J Am Chem Soc ; 145(18): 9994-10000, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37125994

RESUMEN

Herein, we report the synthesis of a bifunctional photocatalyst, Zr-OTf-EY, through sequential modifications of metal cluster nodes in a metal-organic layer (MOL). With eosin Y and strong Lewis acids on the nodes, Zr-OTf-EY catalyzes cross-coupling reactions between various C-H compounds and electron-deficient alkenes or azodicarboxylate to afford C-C and C-N coupling products, with turnover numbers of up to 1980. In Zr-OTf-EY-catalyzed reactions, Lewis acid sites bind the alkenes or azodicarboxylate to increase their local concentrations and electron deficiency for enhanced radical additions, while EY is stabilized by site isolation on the MOL to afford a long-lived catalyst for hydrogen atom transfer. The proximity between photostable EY sites and Lewis acids on the nodes of Zr-OTf-EY enhances the catalytic efficiency by approximately 400 times over the homogeneous counterpart in the cross-coupling reactions.

6.
Chemistry ; 29(39): e202300906, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37115502

RESUMEN

New chiral and achiral dyes were synthesized by using clean, highly efficient Diels-Alder 'click' reactions. We prepared pure endo- and exo- stereoisomers and blue-light-emitting single crystal of an exo-isomer. 1 H NMR spectroscopy and single-crystal X-ray diffraction reveal the precise spatial configurations of endo- and exo-dye stereoisomers. Single-crystal X-ray diffraction results reveal the dynamic nature of Diels-Alder covalent bonds. By reversible formation and cleavage of dynamic covalent bonds, an achiral dye was converted to a chiral dye, where achiral dansyl dye moiety was replaced by chiral moiety. Before achiral-to-chiral dye conversion, the dye system displayed dansyl acceptor green light-emitting color due to intramolecular fluorescence resonance energy transfer, where the blue emission of pyrene donor fluorophore was not observed. After achiral-to-chiral dye conversion, light-emitting colors of dye system change from green to blue, where the pyrene-to-dansyl fluorophore energy transfer was suppressed, and pyrene fluorophore blue emission was restored. Chiral transfer occurs in a chiral dye solid from non-chromophore alky chirality to pyrene chromophore. Thus, the chiral dye solid displayed chiral optical behaviors, i. e., circular dichroism and circularly polarized luminescence.

7.
FASEB J ; 37(5): e22929, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37086093

RESUMEN

The cell types and conductance that contribute to normal cardiac functions remain under investigation. We used mice that express an enhanced green fluorescent protein (eGFP)-histone 2B fusion protein driven off the cell-specific endogenous promoter for Pdgfra to investigate the distribution and functional role of PDGFRα+ cells in the heart. Cardiac PDGFRα+ cells were widely distributed within the endomysium of atria, ventricle, and sino-atrial node (SAN) tissues. PDGFRα+ cells formed a discrete network of cells, lying in close apposition to neighboring cardiac myocytes in mouse and Cynomolgus monkey (Macaca fascicularis) hearts. Expression of eGFP in nuclei allowed unequivocal identification of these cells following enzymatic dispersion of muscle tissues. FACS purification of PDGFRα+ cells from the SAN and analysis of gene transcripts by qPCR revealed that they were a distinct population of cells that expressed gap junction transcripts, Gja1 and Gjc1. Cardiac PDGFRα+ cells generated spontaneous transient inward currents (STICs) and spontaneous transient depolarizations (STDs) that reversed at 0 mV. Reversal potential was maintained when ECl = -40 mV. [Na+ ]o replacement and FTY720 abolished STICs, suggesting they were due to a non-selective cation conductance (NSCC) carried by TRPM7. PDGFRα+ cells also express ß2 -adrenoceptor gene transcripts, Adrb2. Zinterol, a selective ß2 -receptor agonist, increased the amplitude and frequency of STICs, suggesting these cells could contribute to adrenergic regulation of cardiac excitability. PDGFRα+ cells in cardiac muscles generate inward currents via an NSCC. STICs generated by these cells may contribute to the integrated membrane potentials of cardiac muscles, possibly affecting the frequency of pacemaker activity.


Asunto(s)
Miocardio , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas , Canales Catiónicos TRPM , Animales , Ratones , Cationes/metabolismo , Corazón/fisiología , Macaca fascicularis/metabolismo , Potenciales de la Membrana/fisiología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Miocardio/metabolismo
8.
Nano Lett ; 23(5): 1954-1960, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36790322

RESUMEN

Highly efficient perovskite optoelectronics (POEs) have been limited by nonradiative recombination. We report a strategy to inhibit the nonradiative recombination of 2D triphenylamine polymers in the hole transport layer (HTL) via introducing electron-donating groups to enhance the conjugation effect and electron cloud density. The conjugated systems with electron-donating groups present smaller energy level oscillation compared to the ones with electron-absorbing groups, as confirmed by nonadiabatic molecular dynamics (NAMD) calculation. Further study reveals that the introduction of low-frequency phonons in the electron-donating group systems shortens the nonadiabatic coupling and inhibits the nonradiative recombination. Such electron-donating groups can decrease the valence band maximum of 2D polymers and promote hole transport. Our report provides a new design strategy to suppress nonradiative recombination in HTL for application in efficient POEs.

9.
J Am Chem Soc ; 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36753526

RESUMEN

Metal-organic layers (MOLs), a monolayered version of metal-organic frameworks (MOFs), have recently emerged as a novel two-dimensional molecular material platform to design multifunctional catalysts. MOLs inherit the intrinsic molecular tunability of MOFs and yet have more accessible and modifiable building blocks. Here we report molecular engineering of six MOLs via modulated solvothermal synthesis between HfCl4 and three photosensitizing ligands followed by postsynthetic modification with two carboxylate-containing cobaloximes for tandem and synergistic photocatalysis. Morphological and structural characterization by transmission electron microscopy and atomic force microscopy and compositional analysis by inductively coupled plasma-mass spectrometry and nuclear magnetic resonance spectroscopy establish the MOLs as flat nanoplates with a periodic lattice structure of hexagonal symmetry. The MOLs efficiently catalyze tandem dehydrogenative coupling reactions and synergistic Heck-type coupling reactions. The most active MOL catalyst was used for the gram-scale synthesis of vesnarinone, a cardiotonic agent, in 80% yield with a turnover number of 400 and in eight consecutive reaction cycles without significant loss of activities.

10.
Methods Mol Biol ; 2524: 209-221, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35821474

RESUMEN

Aberrant splicing of precursor messenger RNA (pre-mRNA) can generate abnormal transcripts, and most of the human diseases have been shown to associate with abnormal splicing of pre-mRNA. Conventional methods require sample lysis and thus cannot be used for monitoring pre-mRNA splicing in real time. This chapter guides how to develop an intron-retained bioluminescence (BL) reporter, which simulates the splicing process of pre-mRNA in vitro and in vivo noninvasively. In the following, we illustrate the design and construction of RLuc-intron and the methods of BL experiments in vitro and in vivo. The exemplified results show that our reporter is suitable for high-throughput screening of splicing inhibitors for the therapies of the diseases caused by aberrant splicing.


Asunto(s)
Precursores del ARN , Empalme del ARN , Diagnóstico por Imagen , Humanos , Intrones/genética , Precursores del ARN/genética , Precursores del ARN/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
11.
J Am Chem Soc ; 144(24): 10694-10699, 2022 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-35687864

RESUMEN

Herein, we report the synthesis of a metal-organic layer, Hf-Ru-Au, containing Ru(bipyridine)32+-type photosensitizers and (phosphine)-AuCl catalysts for photoredox Au-catalyzed cross-coupling of allenoates, alkenes, or alkynes with aryldiazonium salts to afford furanone, tetrahydrofuran, or aryl alkyne derivatives, respectively. Site isolation of (phosphine)-AuCl complexes in Hf-Ru-Au prevents Au catalyst deactivation via ligand redistribution, Au(I) disproportionation, and aryl-phosphine reductive elimination, while the proximity between the Ru photosensitizers and Au catalysts enhances catalytic efficiency, with 14-200 times higher activity over those of the homogeneous controls in the cross-coupling reactions.


Asunto(s)
Oro , Fármacos Fotosensibilizantes , Alquenos , Alquinos , Catálisis
12.
Acta Otolaryngol ; 142(5): 375-380, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35549633

RESUMEN

BACKGROUND: The effects of graft thickness on tympanoplasty is uncertain. OBJECTIVE: To compare the results of endoscopic tympanoplasty using different thicknesses of autologous tissues. METHODS: This retrospective analysis included 186 patients who received type I tympanoplasty, divided into three main groups based of grafting material: perichondrium (A), cartilage-perichondrium (B), or cartilage-perichondrium plus additional perichondrium (C). Group A was subdivided based on whether the placement was inside (A1) or outside (A2) of the malleus. The hearing improvement, graft success rate, and surgery duration were analysed. RESULTS: Statistical analysis showed significant hearing improvement in the three main groups (p < .001); recovery in group A occurred the earliest. Six months postoperatively, group A1 showed significantly greater hearing recovery compared with groups B and C (p < .05). There were no statistical differences the other groups (p > .05) or in the graft success rate among the three main groups (p = .235). The surgery duration of group A was significantly longer than that of groups B and C (p < .001). CONCLUSION AND SIGNIFICANCE: Our results suggest that graft thickness affects hearing recovery; however, graft thickness does not affect the rate of grafting success. Endoscopic transplantation of the perichondrium is more difficult and requires more time.


Asunto(s)
Perforación de la Membrana Timpánica , Timpanoplastia , Fascia/trasplante , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Perforación de la Membrana Timpánica/cirugía , Timpanoplastia/métodos
13.
Chem Commun (Camb) ; 57(75): 9626, 2021 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-34558576

RESUMEN

Correction for 'Dynamic visualization of mRNA splicing variants with a transactivating reporter' by Si Chen et al., Chem. Commun., 2021, DOI: 10.1039/d1cc02439f.

14.
Chem Commun (Camb) ; 57(75): 9594-9597, 2021 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-34546238

RESUMEN

Dynamic changes in intron sequences, with their loss and gain, are poorly detected due to the limited methods for the non-invasive monitoring of the pre-mRNA splicing process. Here, we describe the design of a two-step transcriptional activation (TSTA) reporter for the real-time imaging of the splicing process in living subjects. By taking advantage of the strong transactivating properties of the GAL4-VP16 fusion protein, which can target upstream activation sequence (UAS) elements to boost subsequent firefly luciferase reporter gene expression, we successfully and consistently detected the dynamic pre-mRNA splicing activity in response to exogenous splicing modulators in living cells and animals. Our findings provide a valuable tool for the high-throughput screening of splicing modulators, which could speed up the development of new drugs for the treatment of disordered splicing diseases.


Asunto(s)
ARN Mensajero/genética , Transactivadores/genética , Humanos , Empalme del ARN/genética , ARN Mensajero/metabolismo , Transactivadores/metabolismo
15.
J Am Chem Soc ; 143(37): 15391-15399, 2021 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34510888

RESUMEN

An oxocarbenium-olefin cross metathesis occurs during Brønsted acid catalyzed reactions of 1H-isochromene acetals with vinyl diazo compounds. Formally a carbonyl-alkene [2 + 2]-cyclization between isobenzopyrylium ions and the vinyl group of vinyl diazoesters, the retro-[2 + 2] cycloaddition produces a tethered alkene and a vinyl diazonium ion that, upon loss of dinitrogen, undergoes a highly selective carbocationic cascade rearrangements to diverse products whose formation is controlled by reactant substituents. Polysubstituted benzobicyclo[3.3.1]oxocines, benzobicyclo[3.2.2]oxepines, benzobicyclopropane, and naphthalenes are obtained in good to excellent yields and selectivities. Furthermore, isotopic tracer and control experiments shed light on the oxocarbenium-olefin metathesis/rearrangement process as well as on the origin of the interesting substituent-dependent selectivity.

16.
Org Lett ; 23(16): 6542-6546, 2021 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-34370472

RESUMEN

1,2,3-Triazine 1-oxides are formed by nitrosyl addition from tert-butyl nitrite to the vinylogous position of vinyl diazo compounds. This transformation, which is a formal intermolecular [5 + 1] cycloaddition, occurs under mild conditions, with high functional group tolerance and regioselectivity, and can be employed for late-stage functionalization. Upon heating at refluxing chlorobenzene temperature, these triazine-N-oxides undergo dinitrogen extrusion to form isoxazoles in very high yields.

17.
Chem Sci ; 12(13): 4819-4824, 2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-34168758

RESUMEN

Brønsted acid catalyzed formal [4 + 4]-, [4 + 3]-, and [4 + 2]-cycloadditions of donor-acceptor cyclobutenes, cyclopropenes, and siloxyalkynes with benzopyrylium ions are reported. [4 + 2]-cyclization/deMayo-type ring-extension cascade processes produce highly functionalized benzocyclooctatrienes, benzocycloheptatrienes, and 2-naphthols in good to excellent yields and selectivities. Moreover, the optical purity of reactant donor-acceptor cyclobutenes is fully retained during the cascade. The 1,3-dicarbonyl product framework of the reaction products provides opportunities for salen-type ligand syntheses and the construction of fused pyrazoles and isoxazoles that reveal a novel rotamer-diastereoisomerism.

18.
Angew Chem Int Ed Engl ; 60(34): 18484-18488, 2021 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-34043866

RESUMEN

A general catalytic methodology for the synthesis of pyrazolines from α-diazo compounds and conjugated alkenes is reported. The direct hydrogen atom transfer (HAT) process of α-diazo compounds promoted by the tert-butylperoxy radical generates electrophilic diazomethyl radicals, thereby reversing the reactivity of the carbon atom attached with the diazo group. The regiocontrolled addition of diazomethyl radicals to carbon-carbon double bonds followed by intramolecular ring closure on the terminal diazo nitrogen and tautomerization affords a diverse set of pyrazolines in good yields with excellent regioselectivity. This strategy overcomes the limitations of electron-deficient alkenes in traditional dipolar [3+2]-cycloaddition of α-diazo compounds with alkenes. Furthermore, the straightforward formation of the diazomethyl radicals provides umpolung reactivity, thus opening new opportunities for the versatile transformations of diazo compounds.

19.
Am J Physiol Cell Physiol ; 320(6): C966-C973, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33788632

RESUMEN

Two types of voltage-dependent inward currents were evoked by depolarization in murine antral smooth muscle cells (SMCs) bathed in Ca2+-containing physiological solution: high-voltage-activated (HVA) and low-voltage-activated (LVA) inward currents. We examined whether the LVA current was due to: 1) T-type Ca2+ channels, 2) Ca2+-activated Cl-channels, 3) nonselective cation channels (NSCC), or 4) voltage-dependent K+ channels. Replacement of external Ca2+ (2 mM) with equimolar Ba2+ increased the amplitude of the HVA current but blocked the LVA current. Nicardipine blocked the HVA current, and in the presence of nicardipine, T-type Ca2+ blockers failed to block LVA current. A Cl- channel antagonist had little effect on LVA current. Cation-free external solution completely abolished both HVA and LVA currents. Addition of Ca2+ to the solution restored only HVA currents. Addition of K+ (5 mM) to otherwise cation-free solution induced LVA current that reversed at -20 mV. These data suggest that LVA current is not due to T-type Ca2+ channels, Ca2+-activated Cl- channels, or NSCC. A-type K+ (KA) currents and delayed rectifying K+ (KDR) currents can be resolved in antral SMCs dialyzed with a solution containing 140 mM K+. When cells were exposed to high K+ external solution and dialyzed with Cs+-rich solution in the presence of nicardipine, LVA current was evoked and reversed at positive potentials. LVA currents were blocked by K+ channel blockers, 4-aminopyridine, and tetraethylammonium. In conclusion, LVA inward currents can be generated by K+ influx via KA channels in murine antral SMCs when cells were dialyzed with Cs+-rich solution.


Asunto(s)
Potenciales de la Membrana/fisiología , Miocitos del Músculo Liso/metabolismo , Animales , Artefactos , Calcio/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/metabolismo , Células Cultivadas , Masculino , Potenciales de la Membrana/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Miocitos del Músculo Liso/efectos de los fármacos , Técnicas de Placa-Clamp/métodos , Canales de Potasio/metabolismo
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