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1.
Biomacromolecules ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38720431

RESUMEN

Reactive oxygen species (ROS) have emerged as a promising treatment option for antibacterial and biofilm eradication. However, their therapeutic efficacy is significantly hampered by the unique microenvironments of diabetic wounds. In this study, we designed and synthesized porphyrin-based Fe covalent organic frameworks (Fe-COF) through a Schiff base condensation reaction. Subsequently, Fe-COF were encapsulated with hyaluronic acid (HA) through electrostatic adsorption, resulting in a novel formulation named HA-Fe-COF for diabetic wound healing. HA-Fe-COF were engineered to respond to hyaluronidase in the infected wound, leading to the controlled release of Fe-COF. Those released Fe-COF served a dual role as photosensitizers, generating singlet oxygen and localized heating when exposed to dual light sources. Additionally, they acted as peroxidase-like nanozymes, facilitating the production of ROS through enzymatic reactions. This innovative approach enabled a synergistic therapeutic effect combining photodynamic, photothermal, and chemodynamic modalities. Furthermore, the sustained release of HA from HA-Fe-COF promoted angiogenesis, collagen deposition, and re-epithelialization during the diabetic wound healing process. This "all-in-one" strategy offers a novel approach for the development of antimicrobial and biofilm eradication strategies that minimize damage to healthy tissues in vivo.

2.
BMC Anesthesiol ; 24(1): 136, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38594630

RESUMEN

BACKGROUND: Adequate preoperative evaluation of the post-intubation hemodynamic instability (PIHI) is crucial for accurate risk assessment and efficient anesthesia management. However, the incorporation of this evaluation within a predictive framework have been insufficiently addressed and executed. This study aims to developed a machine learning approach for preoperatively and precisely predicting the PIHI index values. METHODS: In this retrospective study, the valid features were collected from 23,305 adult surgical patients at Peking Union Medical College Hospital between 2012 and 2020. Three hemodynamic response sequences including systolic pressure, diastolic pressure and heart rate, were utilized to design the post-intubation hemodynamic instability (PIHI) index by computing the integrated coefficient of variation (ICV) values. Different types of machine learning models were constructed to predict the ICV values, leveraging preoperative patient information and initiatory drug infusion. The models were trained and cross-validated based on balanced data using the SMOTETomek technique, and their performance was evaluated according to the mean absolute error (MAE), root mean square error (RMSE), mean absolute percentage error (MAPE) and R-squared index (R2). RESULTS: The ICV values were proved to be consistent with the anesthetists' ratings with Spearman correlation coefficient of 0.877 (P < 0.001), affirming its capability to effectively capture the PIHI variations. The extra tree regression model outperformed the other models in predicting the ICV values with the smallest MAE (0.0512, 95% CI: 0.0511-0.0513), RMSE (0.0792, 95% CI: 0.0790-0.0794), and MAPE (0.2086, 95% CI: 0.2077-0.2095) and the largest R2 (0.9047, 95% CI: 0.9043-0.9052). It was found that the features of age and preoperative hemodynamic status were the most important features for accurately predicting the ICV values. CONCLUSIONS: Our results demonstrate the potential of the machine learning approach in predicting PIHI index values, thereby preoperatively informing anesthetists the possible anesthetic risk and enabling the implementation of individualized and precise anesthesia interventions.


Asunto(s)
Anestesia , Hemodinámica , Adulto , Humanos , Estudios Retrospectivos , Intubación Intratraqueal , Aprendizaje Automático
3.
Biosens Bioelectron ; 257: 116332, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38677016

RESUMEN

In situ detection of dopamine (DA) at single-cell level is critical for exploring neurotransmitter-related biological processes and diseases. However, the low content of DA and a variety of distractors with similar oxidation potentials as DA in cells brought great challenges. Here, a sensitive and specific electrochemical nanosensor was proposed for in situ detection of DA in single living cells based on nanodiamond (ND) and molecularly imprinted polymer (MIP)-functionalized carbon fiber nanoelectrode (ND/MIP/CFNE). Due to its excellent electrocatalytic property, ND was modified to the surface of CFNE based on amide bonding. Compared with bare CFNE, ND-modified CFNE can enhance oxidation currents of DA by about 4-fold, improving signal-to-noise ratio and detection sensitivity. MIP was further electropolymerized on the surface of nanoelectrodes to achieve specific capture and recognition of DA, which could avoid the interference of complex matrix and analogs in cells. Taking advantage of the precise positioning capability of a single-cell analyzer and micromanipulator, ND/MIP/CFNE could be precisely inserted into different locations of single cells and monitor oxidation signal of DA. The concentration of DA in the cytoplasm of single pheochromocytoma (PC12) cell was measured to be about 0.4 µM, providing a sensitive and powerful method for single-cell detection. Furthermore, the nanoelectrodes can monitor the fluctuation of intracellular DA under drug stimulation, providing new ideas and methods for new drug development and efficacy evaluation.


Asunto(s)
Técnicas Biosensibles , Dopamina , Técnicas Electroquímicas , Polímeros Impresos Molecularmente , Análisis de la Célula Individual , Dopamina/análisis , Dopamina/química , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Células PC12 , Técnicas Electroquímicas/métodos , Polímeros Impresos Molecularmente/química , Animales , Ratas , Nanodiamantes/química , Electrodos , Fibra de Carbono/química , Impresión Molecular/métodos , Límite de Detección , Polímeros/química
4.
Artículo en Inglés | MEDLINE | ID: mdl-38547517

RESUMEN

ABSTRACT: Chronic kidney disease (CKD) is a significant global health threat that imposes a substantial burden on both individuals and societies. CKD frequently correlates with cardiovascular events, particularly left ventricular hypertrophy (LVH), which contributes to the high mortality rate associated with CKD. Fibroblast growth factor (FGF) 23, a hormone primarily involved in regulating calcium and phosphorus metabolism, has been identified as a major risk factor for LVH in CKD patients. Elevated serum FGF23 levels are known to induce LVH and myocardial fibrosis by activating the FGF receptor 4 (FGFR4) signal pathway. Therefore, targeting FGFR4 and its downstream signaling pathways holds potential as a treatment strategy for cardiac dysfunction in CKD. In our current study, we have discovered that Hypericin, a key component derived from Hypericum perforatum, has the ability to alleviate CKD-related LVH by targeting the FGFR4/phospholipase C gamma 1 (PLCγ1) signaling pathway. Through in vitro experiments using rat cardiac myocyte H9c2 cells, we observed that Hypericin effectively inhibits FGF23-induced hypertrophy and fibrosis by suppressing the FGFR4/PLCγ1/calcineurin/nuclear factor of activated T-cell (NFAT3) signaling pathway. Additionally, our in vivo studies using mice on a high phosphate diet and rat models of 5/6 nephrectomy demonstrated that Hypericin has therapeutic effects against CKD-induced LVH by modulating the FGFR4/PLCγ1/calcineurin/NFAT3 signaling pathway. In conclusion, our research highlights the potential of Hypericin as a candidate for the treatment of CKD-induced cardiomyopathy. By suppressing the FGFR4/PLCγ1 signaling pathway, Hypericin shoaws promise in attenuating LVH and myocardial fibrosis associated with CKD.

5.
Ann Jt ; 9: 10, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38529291

RESUMEN

Background and Objective: Connexin 43 (Cx43) is the main gap junction (GJ) protein and hemichannel protein in bone tissue. It is involved in the formation of hemichannels and GJs and establishes channels that can communicate directly to exchange substances and signals, affecting the structure and function of osteocytes. CX43 is very important for the normal development of bone tissue and the establishment and balance of bone reconstruction. However, the molecular mechanisms by which CX43 regulates osteoblast function and homeostasis have been less well studied, and this article provides a review of research in this area. Methods: We searched the PubMed, EMBASE, Cochrane Library, and Web of Science databases for studies published up to June 2023 using the keywords Connexin 43/Cx43 and Osteocytes. Screening of literatures according to inclusion and exclusion guidelines and summarized the results. Key Content and Findings: Osteocytes, osteoblasts, and osteoclasts all express Cx43 and form an overall network through the interaction between GJs. Cx43 is not only involved in the mechanical response of bone tissue but also in the regulation of signal transduction, which could provide new molecular markers and novel targets for the treatment of certain bone diseases. Conclusions: Cx43 is expressed in osteoblasts, osteoclasts, and osteoclasts and plays an important role in regulating the function, signal transduction, and mechanotransduction of osteocytes. This review offers a new contribution to the literature by summarizing the relationship between Cx43, a key protein of bone tissue, and osteoblasts.

6.
Small ; : e2310247, 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38368267

RESUMEN

Chemodynamic therapy (CDT) has emerged as a promising approach for treating infected diabetic wounds, while reliable imaging technology for simultaneous monitoring of ROS and therapeutic processes is still a formidable challenge. Herein, smart covalent organic framework (COF) nanoreactors (COF NRs) are constructed by hyaluronic acid (HA) packaged glucose oxidase (GOx) covalently linked Fe-COF for diabetic wound healing. Upon the breakdown of the HA protective layer, GOx consumes glucose to produce gluconic acid and hydrogen peroxide (H2 O2 ), resulting in decreased local pH and H2 O2 supplementation. Density functional theory (DFT) calculations show that Fe-COF has high catalytic activity towards H2 O2 , leading to in situ generation of hydroxyl radicals (·OH) for sterilization, and the localized downregulation of glucose effectively improved the microenvironment of diabetic wounds. Meanwhile, based on the near-infrared photothermal imaging of oxidized 3,3',5,5'-tetramethylbenzidine (oxTMB), the authors showed that TMB can be applied for the point-of-care testing of ·OH and glucose, and assessing the sterilization progress in vivo. More significantly, the facile photothermal signaling strategy can be extended to monitor various ROS-mediated therapeutic systems, enabling accurate prediction of treatment outcomes.

7.
Anal Chem ; 96(5): 1852-1860, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38279192

RESUMEN

The self-powered electrochemical sensor (SPES), an analytical sensing device without external power supply, is integrated with the dual function of power supply and detection performance, which lay the foundation for the development of intelligent and portable electrochemical sensing devices. Herein, a novel SPES based on a zinc-air battery was constructed for the detection of hydrogen sulfide (H2S) in the lysate of colon cancer cells. Typically, an Fe/Fe3C@graphene foam with oxygen reduction performance was used to construct SPES based on a zinc-air battery (ZAB-SPES), which brings the open-circuit voltage to 1.30 V. Among them, the poisoning effect of H2S causes the catalytic performance of the oxygen reduction catalyst to decrease, causing a significant decrease in the discharge voltage of ZAB. Based on this principle, ZAB-SPES was constructed for the detection of H2S using a digital multimeter. The proposed ZAB-SPES demonstrated good selectivity and reproducibility for detecting H2S compared to the results of the H2S-specific fluorescence probe. This strategy enriches the idea of constructing a self-powered sensor and a digital multimeter as detection devices, providing technical support for the portability of SPESs.

8.
Chem Commun (Camb) ; 60(12): 1546-1562, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38240334

RESUMEN

Cyanation has attracted considerable attention in organic synthesis because nitriles are key structural motifs in numerous important dyes, agrochemicals, natural products and drug molecules. As the fourth generation of cyanating reagents, isocyanides occupy a prominent place in the synthesis of nitriles due to their favorable stability, easy operability and high reactivity. In recent years, three types of cyanation with isocyanides have been established: the cleavage of the C-NC bond of tertiary alkyl isocyanides (Type I), the rearrangement of aryl isocyanides with azides (Type II), and the reductive cyanation of ketones with α-acidic isocyanides (Type III). This review focuses on advances in cyanation with isocyanides with an emphasis on reaction scope, limitations and mechanisms, which could reveal their remarkable value and superiority for accessing various nitriles. In addition, the future development prospects of this specific field are also introduced. We believe that this feature article will serve as a comprehensive tool to navigate cyanation with isocyanides across the vast area of synthetic chemistry.

9.
Psychopharmacology (Berl) ; 241(1): 75-88, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37715015

RESUMEN

BACKGROUND: In our previous study, we showed simvastatin exerts an antidepressant effect and inhibits neuroinflammation. Given the role of synaptic impairment in depression development, we investigate the effect of simvastatin on synaptic plasticity in depression and the related mechanisms. METHODS: Electrophysiological analysis, Golgi staining, and transmission electron microscope were performed to analyze the effect of simvastatin on synaptic impairment in depression. In addition, the localization and reactivity of N-methyl-D-aspartate receptor (NMDAR) subunits and the downstream signaling were investigated to explore the mechanism of simvastatin's effect on synaptic plasticity. RESULTS: Simvastatin ameliorated the reduction of the magnitude of long-term potentiation (LTP) in Schaffer collateral-CA1, restored hippocampal dendritic spine density loss, improved the number of spine synapses, reversed the reduction in BrdU-positive cells in chronic mild stress (CMS)-induced depressed mice, and ameliorated NMDA-induced neurotoxicity in hippocampal neurons. Dysfunction of NMDAR activity in the hippocampus is associated with depression. Simvastatin treatment reversed the surface expression and phosphorylation changes of NMDAR subunits in NMDA-treated hippocampal neurons and depressed mice. In addition, simvastatin further increased the levels of mature BDNF, activating TrkB-Akt-mTOR signaling, which is critical for synaptic plasticity. CONCLUSIONS: These findings suggest that simvastatin can improve the dysfunction of NMDAR and ameliorate hippocampal synaptic plasticity impairment in depressed mice.


Asunto(s)
N-Metilaspartato , Receptores de N-Metil-D-Aspartato , Ratones , Animales , Receptores de N-Metil-D-Aspartato/metabolismo , N-Metilaspartato/metabolismo , Simvastatina/farmacología , Simvastatina/metabolismo , Plasticidad Neuronal/fisiología , Hipocampo , Potenciación a Largo Plazo , Sinapsis/metabolismo , Transmisión Sináptica/fisiología
10.
Anal Bioanal Chem ; 416(1): 163-173, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37930375

RESUMEN

Alpha-fetoprotein (AFP) is inextricably linked to various diseases, including liver cancer. Thus, detecting the content of AFP in biology has great significance in diagnosis, treatment, and intervention. Motivated by the urgent need for affordable and convenient electronic sensors in the analysis and detection of aqueous biological samples, we combined the solution-gated graphene transistor (SGGT) with the catalytic reaction of enzyme nanoprobes (HRP-AuNPs-Ab2) to accurately sense AFP. The SGGT immunosensor demonstrated high specificity and stability, excellent selectivity, and excessive linearity over a range of 4 ng/mL to 500 ng/mL, with the lower detection limit down to 1.03 ng/mL. Finally, clinical samples were successfully detected by the SGGT immunosensor, and the results were consistent with chemiluminescence methods that are popular in hospitals for detecting AFP. Notably, the SGGT immunosensor is also recyclable, so it has excellent potential for use in high-throughput detection.


Asunto(s)
Técnicas Biosensibles , Grafito , Nanopartículas del Metal , Humanos , alfa-Fetoproteínas/análisis , Oro , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Inmunoensayo/métodos , Límite de Detección
11.
J Pharm Pharmacol ; 76(2): 115-121, 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38150242

RESUMEN

AIM: Our study is to investigate the effects of triazole antifungal drugs on the pharmacokinetics of lorlatinib in rats. METHODS: The samples were precipitated with methanol. Chromatographic separation was performed on a ultra-performance liquid chromatography (UPLC) system using a BEH C18 column. The mobile phase consisted of 0.1% formic acid water and methanol. Lorlatinib and crizotinib (internal standard) were detected in multiple reaction monitoring mode. The fragment ions were 407.3-228.07 for lorlatinib and m/z 450.3-260.0 for crizotinib. Lorlatinib and different triazole antifungal drugs were given to Sprague Dawley rats by gavage, and blood was collected from the tail vein at a certain time point. The validated UPLC-MS/MS method was applied to a drug interaction study of ketoconazole, voriconazole, itraconazole, and posaconazole with lorlatinib in rats. RESULTS: Ketoconazole and voriconazole significantly inhibited lorlatinib metabolism. When administration with ketoconazole and voriconazole, the area under the curve from time zero to infinity of lorlatinib increased by 49.0% and 104.3%, respectively; the clearance decreased by 40.0% and 40.0%, respectively. While itraconazole and posaconazole did not affect lorlatinib pharmacokinetics. CONCLUSION: The UPLC-MS/MS-based assay is helpful to further understand the pharmacokinetics of lorlatinib in rats, and confirmed the findings that the combination of lorlatinib with CYP3A inhibitors should be avoided as predicted by our pre-clinical studies.


Asunto(s)
Aminopiridinas , Antifúngicos , Itraconazol , Lactamas , Pirazoles , Ratas , Animales , Voriconazol/farmacocinética , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Ratas Sprague-Dawley , Cetoconazol , Crizotinib , Metanol , Triazoles , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los Resultados
12.
Int J Syst Evol Microbiol ; 73(12)2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38112722

RESUMEN

Two Gram-stain-negative, rod-shaped, non-spore-forming, strictly aerobic, motile bacteria with a single polar flagellum, designated strains C1424T and C2222T, were isolated from marine alga collected from the sea shore at Yantai, PR China. Strain C1424T grew at 4-37 °C and in the presence of 1-9 % (w/v) NaCl, while strain C2222T grew at 4-32 °C with 1-6 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences and concatenated amino acid sequences of 120 ubiquitous single-copy proteins showed that both strains C1424T and C2222T belonged to the genus Marinomonas, showing highest 16S rRNA gene sequence similarities to the type strains of Marinomonas primoryensis (98.1 %) and Marinomonas dokdonensis (98.1 %), respectively. The major fatty acids of the two strains were C18 : 1 ω6c and/or C18 : 1 ω7c, C16 : 1 ω6c and/or C16 : 1 ω7c and C16 : 0, their predominant polar lipids were phosphatidylethanolamine and phosphatidylglycerol, and their sole respiratory quinone was Q8. On the basis of polyphasic analyses, strains C1424T and C2222T are considered to represent two novel species within the genus Marinomonas, for which the names Marinomonas transparens sp. nov. and Marinomonas sargassi sp. nov. are proposed. The type strains are C1424T (=KCTC 72119T=MCCC 1K03601T) and C2222T (=KCTC 72120T=MCCC 1K03602T), respectively.


Asunto(s)
Ácidos Grasos , Marinomonas , Ácidos Grasos/química , Fosfolípidos/química , Filogenia , ARN Ribosómico 16S/genética , Cloruro de Sodio , Ubiquinona/química , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Análisis de Secuencia de ADN , Hibridación de Ácido Nucleico
13.
Artículo en Inglés | MEDLINE | ID: mdl-37999452

RESUMEN

OBJECTIVE: This article examined the cost-effectiveness of zanubrutinib and ibrutinib for managing relapsed and refractory chronic lymphocytic leukemia from the viewpoint of payers in China and the US. METHODS: Markov models were employed to conduct comparisons. Baseline characteristics and clinical data were extracted from the ALPINE study. The cost-effectiveness outcome indicators encompassed cost, quality-adjusted life years, and the incremental cost-effectiveness ratio. RESULTS: The Markov model analysis revealed that the zanubrutinib group incurred an incremental cost per patient of $-24,586.53 compared to the ibrutinib group. The zanubrutinib group exhibited an incremental utility per capita of 0.28 quality-adjusted life years, resulting in an incremental cost-effectiveness ratio of $-88,068.16 per quality-adjusted life year, which is lower than the payment threshold in China. The willingness-to-pay value in China for 2022 was three times the country's gross domestic product per capita. In the US, patients in the zanubrutinib group experienced per capita incremental costs of $-79,421.56, per capita incremental utility of 0.28 quality-adjusted life years, and an incremental cost-effectiveness ratio of $-284,485.45 per quality-adjusted life year. CONCLUSION: For Chinese payers, zanubrutinib exhibited superior cost-effectiveness compared to ibrutinib. Zanubrutinib proved to be a more affordable option for US payers when considering the payment threshold.

14.
Mikrochim Acta ; 190(11): 459, 2023 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-37921998

RESUMEN

N-doped carbon Co/CoOx with laccase-like activity was directionally designed by pyrolyzing Co-coordination polymer and applied to detect epinephrine, which revealed a new preparation strategy for laccase mimics. The formation mechanism of the N-doped carbon Co/CoOx nanozyme was reconnoitered by a thermogravimetric-mass spectrometry system (TG-MS). N-doped carbon Co/CoOx exhibited outstanding laccase-like activity, and the Michaelis-Menten constant and maximum initial velocity were calculated to be 0.087 mM and 0.0089 µM s-1, respectively. Based on this principle, a simple colorimetric sensing platform was developed for the quantitative detection of epinephrine, which can be used to diagnose pheochromocytoma. In addition, the visual platform for detecting epinephrine exhibited a linear range of 3 to 20 µg mL-1 and a calculated detection limit of 0.42 µg mL-1. Therefore, the proposed colorimetric sensing platform is a promising candidate to be applied in precise early pheochromocytoma diagnosis.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Feocromocitoma , Humanos , Lacasa , Carbono , Epinefrina
15.
Ecotoxicol Environ Saf ; 266: 115543, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37827095

RESUMEN

As the mechanism of paraquat (PQ) poisoning is still not fully elucidated, and no specific treatment has been developed in medical practice, the management of PQ poisoning continues to present a medical challenge. In this study, the objective was to investigate the early metabolic changes in serum metabolism and identify the key metabolic pathways involved in patients with PQ poisoning. Quantitative analysis was conducted to determine the relevant metabolites. Additionally, experiments were carried out in both plasma and cell to elucidate the mechanisms underlying metabolic disorder and cell death in PQ poisoning. The study found that polyunsaturated fatty acids (PUFAs) and their metabolites, such as arachidonic acid (AA) and hydroxy eicosatetraenoic acids (HETEs), were significantly increased by non-enzymatic oxidative reaction. Reactive oxygen species (ROS) production increased rapidly at 2 h after PQ poisoning, followed by an increase in PUFAs at 12 h, and intracellular glutathione, cysteine (Cys), and Fe2+ at 24 h. However, at 36 h later, intracellular glutathione and Cys decreased, HETEs increased, and the expression of SLC7A11 and glutathione peroxidase 4 (GPX4) decreased. Ultrastructural examination revealed the absence of mitochondrial cristae. Deferoxamine was found to alleviate lipid oxidation, and increase the viability of PQ toxic cells in the low dose. In conclusion, unsaturated fatty acids metabolism was the key metabolic pathways in PQ poisoning. PQ caused cell death through the induction of ferroptosis. Inhibition of ferroptosis could be a novel strategy for the treatment of PQ poisoning.


Asunto(s)
Ferroptosis , Paraquat , Humanos , Paraquat/toxicidad , Metabolismo de los Lípidos , Especies Reactivas de Oxígeno/metabolismo , Glutatión/metabolismo
16.
Chem Commun (Camb) ; 59(70): 10540-10543, 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37566103

RESUMEN

A facile protocol for the preparation of indole-isoindole derivatives was developed and proceeds via a palladium-catalyzed [3+2] cyclization of isocyanides with alkynyl imines. In this transformation, the palladium catalyst has a triple role, serving simultaneously as a π acid, a transition-metal catalyst and a hydride ion donor, thus enabling the dual function of isocyanide both as a C1 synthon for cyanation and a C1N1 synthon for imidoylation. Significantly, the reaction is the sole successful example for accessing indole-isoindole derivatives, and will open up new avenues to assemble unique N-heterocycle frameworks. Furthermore, the synthetic value of this protocol is demonstrated in the late-stage modification of physiologically active molecules and in the construction of aggregation-induced emission compounds.

17.
Org Lett ; 25(34): 6272-6277, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37607048

RESUMEN

An unprecedented route for the preparation of fused tetracyclic N-heterocycles is presented through the palladium-catalyzed cyclization of isocyanides with alkyne-tethered aryl iodides. In this transformation, a novel amino-to-alkyl 1,5-palladium migration/intramolecular C(sp3)-C(sp2) coupling sequence was observed first. More importantly, isocyanide exhibited three roles, serving simultaneously as a C1 synthon, a C1N1 synthon, and the donor of C(sp3) for C(sp3)-C(sp2) coupling, and the reaction was the sole successful example that achieved C(sp3)-H activation of isocyanide.

18.
Anal Chim Acta ; 1269: 341341, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37290849

RESUMEN

It is a great challenge to develop an effective super-sensitive capture method for multiplex heavy metal ions (HMIs), because HMIs is extremely toxic to public health and the environment, what's more their contamination is usually multiplex ions pollution. In this work, a 3D high-porous conductive polymer hydrogel was designed and prepared with high-stable and easy mass production, which is very favorable for the industrialization. The polymer hydrogel (g-C3N4-P(Ani-Py)-PAAM) was formed from the mixture of aniline pyrrole copolymer and acrylamide cross-linked with phytic acid as dopant and cross-linker and integrated with g-C3N4. The 3D networked high-porous hydrogel not only exhibits excellent electrical conductivity, but also provides a large surface area for increasing the number of immobilized ions. Importantly, the 3D high-porous conductive polymer hydrogel was applied successfully in electrochemical multiplex sensing of HIMs. The prepared sensor used differential pulse anodic stripping voltammetry exhibited high sensitivities, low detection limit and wide detection ranges for Cd2+, Pb2+, Hg2+ and Cu2+, respectively. Moreover, the sensor showed a high accuracy in lake water test. The preparation and application of the hydrogel in electrochemical sensor provided an availability strategy to capture and detect the various HMIs by electrochemistry in solution and has great commercial application prospect.


Asunto(s)
Metales Pesados , Ácido Fítico , Porosidad , Hidrogeles , Polímeros , Conductividad Eléctrica , Iones
19.
Talanta ; 260: 124613, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37146454

RESUMEN

Covalent organic framework (COF), a kind of porous polymer with crystalline properties, is a periodic porous framework material with precise regulation at atomic level, which can be formed by the orderly connection of pre-designed organic construction units through covalent bonds. Compared with metal-organic frameworks, COFs exhibit unique performance, including tailor-made functions, stronger load ability, structural diversity, ordered porosity, intrinsic stability and excellent adsorption features, are more conducive to the expansion of electrochemical sensing applications and the universality of applications. In addition, COFs can accurately integrate organic structural units with atomic precision into ordered structures, so that the structural diversity and application of COFs can be greatly enriched by designing new construction units and adopting reasonable functional strategies. In this review, we mainly summarized state-of-the-art recent advances of the classification and synthesis strategy of COFs, the design of functionalized COF for electrochemical sensors and COFs-based electrochemical sensing. Then, an overview of the considerable recent advances made in applying outstanding COFs to establish electrochemical sensing platform, including electrochemical sensor based on voltammetry, amperometry, electrochemical impedance spectroscopy, electrochemiluminescence, photoelectrochemical sensor and others. Finally, we discussed the positive outlooks, critical challenges and bright directions of COFs-based electrochemical sensing in the field of disease diagnosis, environmental monitoring, food safety, drug analysis, etc.

20.
Perioper Med (Lond) ; 12(1): 17, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37194032

RESUMEN

BACKGROUND: Perioperative acute kidney injury (AKI) has been one of the leading causes of morbidity and mortality for surgical patients. Pheochromocytoma is a rare, catecholamine-secreting neuroendocrine neoplasm characterized by typical long-term hypertension that needs surgical resection. Our objective was to determine whether intraoperative mean arterial pressures (MAPs) less than 65 mmHg are associated with postoperative AKI after elective adrenalectomy in patients with pheochromocytoma. METHODS: We performed a retrospective review of patients undergoing adrenalectomy for pheochromocytoma between 1991 and 2019 at Peking Union Medical College Hospital, Beijing, China. Two intraoperative phases, before and after tumor resection, were recognized based on distinctly different hemodynamic characteristics. The authors evaluated the association between AKI and each blood pressure exposure in these two phases. The association between the time spent under different absolute and relative MAP thresholds and AKI was then evaluated adjusting for potential confounding variables. RESULTS: We enrolled 560 cases with 48 patients who developed AKI postoperatively. The baseline and intraoperative characteristics were similar in both groups. Though time-weighted average MAP was not associated with postoperative AKI during the whole operation (OR 1.38; 95% CI, 0.95-2.00; P = 0.087) and before tumor resection phase (OR 0.83; 95% CI, 0.65-1.05; P = 0.12), both time-weighted MAP and time-weighted percentage changes from baseline were strongly associated with postoperative AKI after tumor resection, with OR 3.50, 95% CI (2.25, 5.46) and 2.03, 95% CI (1.56, 2.66) in the univariable logistic analysis respectively, and with OR 2.36, 95% CI (1.46, 3.80) and 1.63, 95% CI (1.23, 2.17) after adjusting sex, surgical type (open vs. laparoscopic) and estimated blood loss in the multiple logistic analysis. At any thresholds of MAP less than 85, 80, 75, 70, and 65 mmHg, prolonged exposure was associated with increased odds of AKI. CONCLUSIONS: We found a significant association between hypotension and postoperative AKI in patients with pheochromocytoma undergoing adrenalectomy in the period after tumor resection. Optimizing hemodynamics, especially blood pressure after the adrenal vessel ligation and tumor is resected, is crucial for the prevention of postoperative AKI in patient with pheochromocytoma, which could be different from general populations.

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