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1.
Small ; : e2402534, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850182

RESUMEN

In this study, the copper-nickel (Cu-Ni) bimetallic electrocatalysts for electrochemical CO2 reduction reaction(CO2RR) are fabricated by taking the finely designed poly(ionic liquids) (PIL) containing abundant Salen and imidazolium chelating sites as the surficial layer, wherein Cu-Ni, PIL-Cu and PIL-Ni interaction can be readily regulated by different synthetic scheme. As a proof of concept, Cu@Salen-PIL@Ni(NO3)2 and Cu@Salen-PIL(Ni) hybrids differ significantly in the types and distribution of Ni species and Cu species at the surface, thereby delivering distinct Cu-Ni cooperation fashion for the CO2RR. Remarkably, Cu@Salen-PIL@Ni(NO3)2 provides a C2+ faradaic efficiency (FEC2+) of 80.9% with partial current density (jC 2+) of 262.9 mA cm-2 at -0.80 V (versus reversible hydrogen electrode, RHE) in 1 m KOH in a flow cell, while Cu@Salen-PIL(Ni) delivers the optimal FEC2+ of 63.8% at jC2+ of 146.7 mA cm-2 at -0.78 V. Mechanistic studies indicates that the presence of Cu-Ni interfaces in Cu@Salen-PIL@Ni(NO3)2 accounts for the preserve of high-valence Cu(I) species under CO2RR conditions. It results in a high activity of both CO2-to-CO conversion and C-C coupling while inhibition of the competitive HER.

2.
Cardiovasc Diabetol ; 23(1): 291, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39113032

RESUMEN

BACKGROUND: Atrial fibrillation (AF) is acknowledged as a disease continuum. Despite catheter ablation being recommended as a primary therapy for AF, the high recurrence rates have tempered the initial enthusiasm. Insulin resistance (IR) has been established as an independent predictor for the onset of AF. However, the correlation between non-insulin-based IR indices and late AF recurrence in patients undergoing radiofrequency catheter ablation remains unknown. METHODS: A retrospective cohort of 910 AF patients who underwent radiofrequency catheter ablation was included in the analysis. The primary endpoint was late AF recurrence during the follow-up period after a defined blank period. The relationship between non-insulin-based IR indices and the primary endpoint was assessed using multivariate Cox hazards regression models and restricted cubic splines (RCS). Additionally, the net reclassification improvement and integrated discrimination improvement index were calculated to further evaluate the additional predictive value of the four IR indices beyond established risk factors for the primary outcome. RESULTS: During a median follow-up period of 12.00 months, 189 patients (20.77%) experienced late AF recurrence, which was more prevalent among patients with higher levels of IR. The multivariate Cox hazards regression analysis revealed a significant association between these IR indices and late AF recurrence. Among the four indices, METS-IR provided the most significant incremental effect on the basic model for predicting late AF recurrence. Multivariable-adjusted RCS curves illustrated a nonlinear correlation between METS-IR and late AF recurrence. In subgroup analysis, METS-IR exhibited a significant correlation with late AF recurrence in patients with diabetes mellitus (HR: 1.697, 95% CI 1.397 - 2.063, P < 0.001). CONCLUSION: All the four non-insulin-based IR indices were significantly associated with late AF recurrence in patients undergoing radiofrequency catheter ablation. Addressing IR could potentially serve as a viable strategy for reducing the late AF recurrence rate.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Resistencia a la Insulina , Recurrencia , Humanos , Fibrilación Atrial/cirugía , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Masculino , Femenino , Ablación por Catéter/efectos adversos , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Anciano , Factores de Tiempo , Medición de Riesgo , Resultado del Tratamiento , Biomarcadores/sangre , Valor Predictivo de las Pruebas , Glucemia/metabolismo
3.
Anticancer Drugs ; 35(3): 227-236, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38085677

RESUMEN

Ferroptosis is a novel form of cell death, which is distinguished from apoptosis and necrosis, and characterized by accumulation of lipid-based reactive oxygen species (ROS) in an iron-dependent manner. Erastin, a small molecule, was widely reported to trigger ferroptosis in various kinds of cancer cells, including pancreatic cancer cells by inducing ROS accumulation. However, how erastin treatment exerts cytotoxicity is not still fully understood. In this study, the effects of erastin in causing pancreatic cancer cell death via inducing ferroptosis and apoptosis are investigated. As expected, erastin treatment caused ROS accumulation, increase in iron concentration and non-apoptotic cell death, which is different from that of induced by apoptosis inducer, staurosporine. Interestingly, erastin treatment caused the upregulation of clusterin, which contributes to the regulation of malignant behaviors of pancreatic cancer, including preventing apoptosis and inducing chemoresistance. Without erastin treatment, overexpressed clusterin significantly promoted cell proliferation, which is consistent with its cytoprotective roles. After erastin treatment, overexpressed clusterin decreased erastin-induced ROS accumulation and cell death. By measuring iron concentration, reduced glutathione (GSH) and glutathione peroxidase 4 (GPX4), it is revealed that clusterin caused resistance to erastin-induced ferroptosis potentially via maintaining the enzymatic activity of GPX4, without disturbing GSH amount. Thus, ferroptosis inducer, erastin, may crosstalk with apoptotic cell death via regulating clusterin, indicating a more complex regulatory network between ferroptosis and apoptosis.


Asunto(s)
Adenocarcinoma , Clusterina , Ferroptosis , Neoplasias Pancreáticas , Piperazinas , Humanos , Adenocarcinoma/tratamiento farmacológico , Clusterina/metabolismo , Ferroptosis/efectos de los fármacos , Hierro/metabolismo , Neoplasias Pancreáticas/tratamiento farmacológico , Piperazinas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral
4.
Environ Sci Technol ; 58(26): 11649-11660, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38872439

RESUMEN

Brominated byproducts and toxicity generation are critical issues for ozone application to wastewater containing bromide. This study demonstrated that ultraviolet/ozone (UV/O3, 100 mJ/cm2, 1 mg-O3/mg-DOC) reduced the cytotoxicity of wastewater from 14.2 mg of pentol/L produced by ozonation to 4.3 mg of pentol/L (1 mg/L bromide, pH 7.0). The genotoxicity was also reduced from 1.65 to 0.17 µg-4-NQO/L by UV/O3. Compared with that of O3 alone, adsorbable organic bromine was reduced from 25.8 to 5.3 µg/L by UV/O3, but bromate increased from 32.9 to 71.4 µg/L. The UV/O3 process enhanced the removal of pre-existing precursors (highly unsaturated and phenolic compounds and poly aromatic hydrocarbons), while new precursors were generated, yet the combined effect of UV/O3 on precursors did not result in a significant change in toxicity. Instead, UV radiation inhibited HOBr concentration through both rapid O3 decomposition to reduce HOBr production and decomposition of the formed HOBr, thus suppressing the AOBr formation. However, the hydroxyl radical-dominated pathway in UV/O3 led to a significant increase of bromate. Considering both organic bromine and bromate, the UV/O3 process effectively controlled both cytotoxicity and genotoxicity of wastewater to mammalian cells, even though an emphasis should be also placed on managing elevated bromate. Futhermore, other end points are needed to evaluate the toxicity outcomes of the UV/O3 process.


Asunto(s)
Bromo , Aguas Residuales , Bromo/química , Bromo/toxicidad , Bromatos/química , Procesos Fotoquímicos , Rayos Ultravioleta , Ozono/química , Purificación del Agua/métodos , Aguas Residuales/toxicidad , Mamíferos , Animales , Células CHO , Cricetulus
5.
BMC Med Imaging ; 24(1): 78, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570748

RESUMEN

BACKGROUND: To investigate the feasibility of Diffusion Kurtosis Imaging (DKI) in assessing renal interstitial fibrosis induced by hyperuricemia. METHODS: A hyperuricemia rat model was established, and the rats were randomly split into the hyperuricemia (HUA), allopurinol (AP), and AP + empagliflozin (AP + EM) groups (n = 19 per group). Also, the normal rats were selected as controls (CON, n = 19). DKI was performed before treatment (baseline) and on days 1, 3, 5, 7, and 9 days after treatment. The DKI indicators, including mean kurtosis (MK), fractional anisotropy (FA), and mean diffusivity (MD) of the cortex (CO), outer stripe of the outer medulla (OS), and inner stripe of the outer medulla (IS) were acquired. Additionally, hematoxylin and eosin (H&E) staining, Masson trichrome staining, and nuclear factor kappa B (NF-κB) immunostaining were used to reveal renal histopathological changes at baseline, 1, 5, and 9 days after treatment. RESULTS: The HUA, AP, and AP + EM group MKOS and MKIS values gradually increased during this study. The HUA group exhibited the highest MK value in outer medulla. Except for the CON group, all the groups showed a decreasing trend in the FA and MD values of outer medulla. The HUA group exhibited the lowest FA and MD values. The MKOS and MKIS values were positively correlated with Masson's trichrome staining results (r = 0.687, P < 0.001 and r = 0.604, P = 0.001, respectively). The MDOS and FAIS were negatively correlated with Masson's trichrome staining (r = -626, P < 0.0014 and r = -0.468, P = 0.01, respectively). CONCLUSION: DKI may be a non-invasive method for monitoring renal interstitial fibrosis induced by hyperuricemia.


Asunto(s)
Hiperuricemia , Ratas , Animales , Hiperuricemia/diagnóstico por imagen , Riñón/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Fibrosis
6.
Bioprocess Biosyst Eng ; 47(6): 841-850, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38676737

RESUMEN

D-Allulose 3-epimerase (DAE) is a vital biocatalyst for the industrial synthesis of D-allulose, an ultra-low calorie rare sugar. However, limited thermostability of DAEs hinders their use at high-temperature production. In this research, hyperthermophilic TI-DAE (Tm = 98.4 ± 0.7 ℃) from Thermotoga sp. was identified via in silico screening. A comparative study of the structure and function of site-directed saturation mutagenesis mutants pinpointed the residue I100 as pivotal in maintaining the high-temperature activity and thermostability of TI-DAE. Employing TI-DAE as a biocatalyst, D-allulose was produced from D-fructose with a conversion rate of 32.5%. Moreover, TI-DAE demonstrated excellent catalytic synergy with glucose isomerase CAGI, enabling the one-step conversion of D-glucose to D-allulose with a conversion rate of 21.6%. This study offers a promising resource for the enzyme engineering of DAEs and a high-performance biocatalyst for industrial D-allulose production.


Asunto(s)
Thermotoga , Thermotoga/enzimología , Thermotoga/genética , Carbohidrato Epimerasas/genética , Carbohidrato Epimerasas/química , Carbohidrato Epimerasas/metabolismo , Carbohidrato Epimerasas/biosíntesis , Racemasas y Epimerasas/genética , Racemasas y Epimerasas/metabolismo , Racemasas y Epimerasas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/biosíntesis , Fructosa/metabolismo , Fructosa/biosíntesis , Fructosa/química , Estabilidad de Enzimas , Biocatálisis , Mutagénesis Sitio-Dirigida , Calor
7.
Pak J Med Sci ; 40(3Part-II): 297-302, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38356797

RESUMEN

Objective: To analyze the efficacy of single-channel percutaneous endoscopic lumbar discectomy (PELD) and conventional open surgery in the treatment of lumbar disc herniation (LDH). Methods: This is a retrospective study. A total of 66 patients with LDH admitted to Tianjin Medical University from June 2017 to June 2018 were divided into two groups: the observation group (single-channel PELD) and the control group (posterior lumbar interbody fusion), with 33 cases in each group. The two groups were compared in terms of visual analogue scale(VAS), oswestry disability index (ODI), Japanese Orthopaedic Association Score(JOA), perioperative indicators, clinical efficacy, postoperative complications, changes in inflammatory factors and serum T lymphocyte subsets. Results: The operation time, incision length, intraoperative blood loss, time in bed, hospital stay in the observation group were all lower than those in the control group. At 7d after treatment, the improvement of ODI, VAS and JOA in the observation group were better than that in the control group. At the last follow-up, there was no significant difference in Cobb angle and lumbar lordosis angle between the two groups. The levels of serum IL-1, IL-6 and TNF-α in the observation group were lower than those in the control group. The degree of reduction of serum CD3+ and CD4+ in the observation group were higher than those in the control group. And the level of elevation of CD8+ in the observation group was lower than that in the control group. Moreover, there was no significant difference in CD4+/CD8+ level between the two groups. The excellent rate of surgical results in the observation group was higher than that in the control group. Complications occurred in both groups, with no significant difference between the two groups. Conclusions: Single-channel PELD can achieve superior clinical efficacy over conventional open surgery in the treatment of LDH.

8.
Small ; 19(18): e2207219, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36720005

RESUMEN

The electrocatalytic transformation of carbon dioxide (CO2 ) to formate is a promising route for highly efficient conversion and utilization of CO2 gas, due to the low production cost and the ease of storage of formate. In this work, porous poly(ionic liquid) (PPIL)-based tin-silver (Sn-Ag) bimetallic hybrids (PPILm -Snx Ag10- x ) are prepared for high-performance formate electrolytic generation. Under optimal conditions, an excellent formate Faradaic efficiency of 95.5% with a high partial current density of 214.9 mA cm-2 is obtained at -1.03 V (vs reversible hydrogen electrode). Meanwhile, the high selectivity of formate (>≈83%) is maintained in a wide potential range (>630 mV). Mechanistic studies demonstrate that the presence of Ag-species is vital for the formation, maintenance, and high dispersion of tetravalent Sn(IV)-species, which accounts for the active sites for CO2 -to-formate conversion. Further, the introduction of Ag-species significantly enhances the activity by increasing the electron density near the Fermi energy level.

9.
Insect Mol Biol ; 32(6): 748-760, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37658706

RESUMEN

Autophagy is a process that serves to degrade damaged proteins and organelles, thereby promoting cell homeostasis, differentiation, development and survival. Many miRNAs have been found to have regulatory roles in autophagy. In insects, it has been shown that autophagy is involved in hormone-regulated programmed cell death during metamorphic midgut remodelling. However, whether this is also true during the remodelling of the honey bee midgut is unclear. In the present study, we explored the relationship between autophagy and midgut remodelling and sought to identify miRNAs involved in this physiological process. We found that autophagy occurred during midgut remodelling and that the inhibition of autophagy resulted in midgut dysplasia in prepupae. Differentially expressed miRNAs enriched in the autophagy signalling pathway during midgut remodelling were identified by small RNA-seq. Ame-miR-980-3p, which targets the autophagy-related gene Atg2B, was screened out. Furthermore, abnormal expression of ame-miR-980-3p in the pupal stage led to the thinning of the midgut wall of newly emerged bees (NE). When ame-miR-980-3p expression was inhibited, the intestinal villi of NE bees became significantly shorter and sparse, and the lipid signal in the peritrophic matrix of Pb almost disappeared, indicating that the adult midgut was underdeveloped and the lipid absorption ability was weakened. Taken together, ame-miR-980-3p targeted Atg2B to participate in the regulation of midgut autophagy in the pupae, and the abnormal expression of ame-miR-980-3p would interfere with cell proliferation and death in the process of midgut remodelling, hinder the formation of adult midgut and eventually lead to adult midgut dysplasia and affect the lipid absorption function of the midgut in Apis mellifera.


Asunto(s)
MicroARNs , Abejas/genética , Animales , MicroARNs/genética , Sistema Digestivo/metabolismo , Autofagia/genética , Lípidos
10.
J Org Chem ; 88(2): 882-892, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36602382

RESUMEN

The Pd(cod)Cl2-catalyzed alkoxycarbonylation of conjugated dienes to ß,γ-unsaturated esters was approached by both intramolecular phosphinesulfonate L1 and intermolecular PPh3/PTSA in this study. However, the poor solubility of the Pd/L1 complex and the labile monodentate Pd/PPh3 structure restricts the system efficiency, especially for the scale-up application. By contrast, the stable and well-soluble bidentate Xantphos system allows for the quantitative formation of 3-pentenoate (96%) on a gram scale within 6 h in weakly alkaline N-methylpyrrolidone (NMP), which also functions as a basic site to promote the rate-limiting alcoholysis step while reducing the dosage of ligand to a theoretical value.

11.
Org Biomol Chem ; 21(7): 1450-1456, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36651476

RESUMEN

The Ru(dppbsa)-catalyzed reductive amination of ketones with nitroarenes and nitriles using H2 as the environmentally benign hydrogen surrogate is developed in this study. Cross-experiments demonstrated that both reactions are initiated by the reduction of nitroarenes or nitriles to the corresponding amines, followed by condensation with ketones to give imines and thereafter hydrogenation. However, the route to the formation of an amino-ligated Ru complex during the reduction of nitroarenes or nitriles, followed by in situ nucleophilic C-N coupling, cannot be completely excluded. This newly developed versatile method features good functional group tolerance, which provides a novel design platform for homogeneous catalysts in constructing motifs of secondary amines.

12.
Bull Entomol Res ; 113(3): 368-379, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36849462

RESUMEN

In vitro rearing of honey bee larvae is ideal for bioassay studies; no honey bee stable cell lines are available. Inconsistency of internal development staging of reared larvae and a susceptibility to contamination are common problems encountered. Standardized protocols on rearing larvae in vitro to make the larvae growth and development more similar to that of natural colonies are necessary to ensure the accuracy of experimental results and promote honey bee research as a model organism. Here, we concluded that when larval fasting weight was >160 mg, the time point of gut emptying can be defined as the critical point separating the larval and prepupal stages. In this way, we can conduct precise studies on the prepupal stage, such as organ remodeling during metamorphosis. Simultaneously, we further verified that recombinant AccApidaecin in genetic engineered bacteria added to the larval diet upregulated antibacterial peptide gene expression, and did not stimulate the stress response in larvae, nor did it affect the pupation rate or eclosion rate. This demonstrated that feeding recombinant AccApidaecin can enhance the individual antibacterial ability at the molecular level.


Asunto(s)
Bacterias , Dieta , Abejas , Animales , Larva , Pupa
13.
J Dairy Sci ; 106(3): 1576-1585, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36631321

RESUMEN

Green hydrophobically modified butyrylated dextrin (BD) was used to modulate casein (CN). The CN/BD complex nanoparticles were formed at different CN-to-BD mass ratios based on a pH-driven technology. The interaction force, stability, and emulsifying properties of complex nanoparticles were investigated. The nanoparticles had a negative charge and a small particle size (160.03, 152.6, 155.9, 206.13, and 231.67 nm) as well as excellent thermal stability and environmental stability (pH 4.5, 5.5, 6.6, 7.5, 8.5, and 9.5; ionic strength, 50, 100, 200, and 500 mM). Transmission electron microscopy demonstrated the successful preparation of complex nanoparticles and their spherical shape. Fourier transform infrared spectroscopy, fluorescence spectroscopy, and dissociation analysis results showed that the main driving forces of formed CN/BD nanoparticles were hydrogen bonding and hydrophobic interaction. Furthermore, the CN/BD nanoparticles (CN/BD mass ratio, 1:1; weight/weight) exhibited the lowest creaming index, and optical microscopy showed that it has the most evenly dispersed droplets after 7 d of storage, which indicates that the CN/BD nanoparticles had excellent emulsifying properties. Butyrylated dextrin forms complex nanoparticles with CN through hydrogen bonding and hydrophobic interaction to endow CN with superior properties. The results showed that it is possible to use pH-driven technology to form protein-polysaccharide complex nanoparticles, which provides some information on the development of novel food emulsifiers based on protein-polysaccharide nanoparticles. The study provided significant information on the improvement of CN properties and the development of emulsions based on CN.


Asunto(s)
Caseínas , Nanopartículas , Animales , Caseínas/química , Dextrinas , Emulsionantes , Emulsiones/química , Polisacáridos , Nanopartículas/química , Tamaño de la Partícula
14.
Pestic Biochem Physiol ; 192: 105419, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37105625

RESUMEN

Glyphosate is an herbicide commonly used in agriculture, and its widespread use has adversely affected the survival of nontarget organisms. Among these organisms, bees in particular are important pollinators, and declining bee populations have severely affected crop yields around the world. However, the molecular mechanism by which glyphosate harms bees remains unclear. In our experiment, we screened and cloned a glyphosate-induced gene in Apis cerana cerana (A. c. cerana) and named glyphosate response factor 1 (AccGRF1). Sequence analysis showed that AccGRF1 contains a winged-helix DNA binding domain, which suggests that it belongs to the Forkhead box (Fox) protein family. qRT-PCR and heterologous expression in Escherichia coli and yeast showed that AccGRF1 can respond to glyphosate and oxidative stress. After AccGRF1 knockdown by means of RNA interference (RNAi), the resistance of A. c. cerana to glyphosate stress improved. The results suggested that AccGRF1 is involved in A. c. cerana glyphosate stress tolerance. This study reveals the functions of Fox transcription factors in response to glyphosate stress and provides molecular insights into the regulation of glyphosate responses in honeybees.


Asunto(s)
Glicina , Estrés Oxidativo , Abejas/genética , Animales , Estrés Oxidativo/genética , Interferencia de ARN , Glicina/toxicidad , Proteínas de Insectos/metabolismo , Glifosato
15.
Int J Mol Sci ; 24(3)2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36768418

RESUMEN

Lipophagy plays an important role in regulating lipid metabolism in mammals. The exact function of autophagy-related protein 2 (Atg2) has been investigated in mammals, but research on the existence and functions of Atg2 in Apis mellifera (AmAtg2) is still limited. Here, autophagy occurred in honeybee pupae, which targeted lipid droplets (LDs) in fat body, namely lipophagy, which was verified by co-localization of LDs with microtubule-associated protein 1A/1B light chain 3 beta (LC3). Moreover, AmAtg2 homolog B (AmAtg2B) was expressed specifically in pupal fat body, which indicated that AmAtg2B might have special function in fat body. Further, AmAtg2B antibody neutralization and AmAtg2B knock-down were undertaken to verify the functions in pupae. Results showed that low expression of AmAtg2B at the protein and transcriptional levels led to lipophagy inhibition, which down-regulated the expression levels of proteins and genes related to lipolysis. Altogether, results in this study systematically revealed that AmAtg2B interfered with lipophagy and then caused abnormal lipolysis in the pupal stage.


Asunto(s)
Metabolismo de los Lípidos , Lipólisis , Abejas/genética , Animales , Lipólisis/genética , Pupa/genética , Metabolismo de los Lípidos/genética , Autofagia/genética , Gotas Lipídicas/metabolismo , Mamíferos
16.
N Engl J Med ; 390(11): e27, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38466610
17.
J Org Chem ; 87(6): 4424-4437, 2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35262359

RESUMEN

A concise synthetic route to spiroindoline-fused S-heterocycles was developed through copper-catalyzed [4 + 1] annulation using enaminothiones as donor-acceptor synthons. Both 3-diazoindolin-2-imines and 3-diazooxindoles were amenable to work as effective C1 building blocks. The reaction proceeds via a copper-catalyzed cascade process involving the in situ generation of copper(I) carbene and C-S/C-C bond formation. This synthetic protocol features the use of readily available substrates, diverse substituent tolerance, and good to excellent yields.

18.
J Org Chem ; 87(18): 12019-12035, 2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-36053185

RESUMEN

Efficient palladium-catalyzed vinylic C-H alkenylation and allenylation of gem-disubstituted ethylenes with N-tosylhydrazones of aryl alkyl and diaryl ketones were achieved to access trisubstituted 1,3-dienes and tetrasubstituted allenes, respectively. An aryl to vinyl 1,4-palladium migration/carbene insertion/ß-hydride elimination sequence proceeded to switch the chemo- and regioselectivities to give structurally diverse products. Use of 2-FC6H4OH additive enables enhancement of the reaction efficiency through accelerating the key 1,4-palladium migration process.

19.
Nanotechnology ; 33(35)2022 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-35616242

RESUMEN

Decades have witnessed rapid progress of polymeric materials for vascular embolic or chemoembolic applications. Commercially available polymeric embolics range from gelatin foam to synthetic polymers such as poly(vinyl alcohol). Current systems under investigation include tunable, bioresorbable microspheres composed of chitosan or poly(ethylene glycol) derivatives,in situgelling liquid embolics with improved safety profiles, and radiopaque embolics that are trackablein vivo. In this paper, we proposed a concept of 'responsive embolization'. Sevelamer, clinically proved as an inorganic phosphate binder, was ground into nanoparticles. Sevelamer nanoparticle is highly mobile and capable of swelling and aggregating in the presence of endogenous inorganic phosphate, thereby effectively occluding blood flow in the vessel as it was administered as an embolic agent for interventional therapy. Moreover, citrated sevelamer nanoparticles delayed the aggregation, preferable to penetrate deeply into the capillary system. On the rabbit VX2 liver cancer model, both sevelamer particles aggregates occlude the tumor feeding artery, but backflow was found for the pristine one, thereby citrate passivation of sevelamer nanoparticles endows it have potential from 'bench to bedside' as a new type of vascular embolic.


Asunto(s)
Embolización Terapéutica , Nanopartículas , Animales , Microesferas , Fosfatos , Polímeros , Conejos , Sevelamer
20.
Cardiology ; 147(5-6): 469-478, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36202076

RESUMEN

BACKGROUND: There have been few studies published on the use of contrast media (CM) in metformin-treated patients. In this study, we conducted a systematic review and meta-analysis to investigate the relationship between metformin and contrast-induced acute kidney injury (CI-AKI). METHODS: A comprehensive search of the Medline, PubMed, Embase, and Web of Science databases for literature on associations between metformin use and CI-AKI incidence was conducted. The pooled odds ratio (OR), or relative risk, as well as the corresponding 95% confidence intervals (CIs), was calculated to assess the relationship between metformin and CI-AKI risk as well as the incidence of lactic acidosis (LA). RESULTS: In total, seven studies met our eligibility criteria on associations between metformin use and CI-AKI incidence, comprising 2,325 individuals, with 279 new cases of CI-AKI exposed to CM. The pooled analysis revealed no statistically significant increase in the risk of CI-AKI development in patients who used metformin continuously (random-effects OR: 1.15, 95% CI: 0.70-1.90, p = 0.57). No cases of LA that occurred during CM exposure were reported. CONCLUSION: Metformin can be safely used in patients with moderate renal impairment (eGFR ≥ 30 mL/min/1.73 m2) during CM exposure.


Asunto(s)
Lesión Renal Aguda , Metformina , Humanos , Metformina/efectos adversos , Medios de Contraste/efectos adversos , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/epidemiología , Incidencia , Oportunidad Relativa
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