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1.
BMJ Open Sport Exerc Med ; 10(3): e001831, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39224198

RESUMEN

Background: Time-restricted feeding (TRF), a form of intermittent fasting, limits daily caloric intake to a 6-12 hour window and has been shown to effectively promote weight loss and improve overall health. This systematic review and meta-analysis aimed to compare the effects of TRF versus normal diet (ND) on physical performance and body composition in healthy adults with regular exercise habits. Methods: MEDLINE, PubMed, Embase, SPORTDiscus, Web of Science, CINAHL and the Cochrane Central Register of Controlled Trials (CENTRAL) electronic databases were searched for relevant records. Subgroup analyses were conducted based on the duration of intervention and type of exercise. Physical performance was analysed using standardised mean differences (SMDs) and 95% CIs, whereas body composition parameters were analysed using mean differences (MDs) and 95% CIs. The quality of the included studies was examined using the Cochrane risk-of-bias tool version 2. Results: 15 randomised controlled trials with 361 participants were included in the systematic review. In comparison with the ND group, TRF significantly decreased body weight (MD=-1.76 kg, 95% CI -3.40 to -0.13, p=0.03, I2=11.0%) and fat mass (MD=-1.24 kg, 95% CI -1.87 to -0.61, p<0.001, I2=0.0%). No between-group differences in physical performance-related variables and fat-free mass were found. According to the result of the risk-of-bias assessment, one study showed a low risk of bias, 13 showed some concerns, and one showed a high risk of bias. Conclusion: TRF may be a valuable nutritional strategy to optimise body composition and maintain physical performance in healthy adults engaged in regular exercise. PROSPERO registration number: CRD42022310140.

2.
Org Lett ; 26(36): 7650-7655, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39230939

RESUMEN

As the magic methyl effect is well acknowledged in pharmaceutical molecules, the development of simple and efficient methods for the installment of methyl groups on complex molecules is highly coveted. Hence, we provide a general strategy for radical cascade cyclization of N-(o-cyanobiaryl)acrylamides by utilizing sulfonium salts as the sources of methyl radical and merging photoredox and copper catalysis. This novel protocol can access a wide variety of methylation or remote thioether-substituted benzo-fused N-heterocycle derivatives, which can be easily transformed into diverse highly valuable sulfone and sulfoximine compounds via late-stage diversification. Moreover, to further demonstrate the synthetic utility of this conversion, the methyl(phenyl)sulfide, which serves as both raw material and byproduct, can be recovered and reused in this transformation. The scale-up experiment for the one-pot two-step process directly offers the target product in good yield under the standard conditions.

3.
Org Lett ; 26(30): 6486-6490, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39042855

RESUMEN

An efficient and operationally simple oxidative radical difunctionalization of N-aryl bicyclobutyl (BCB) amides with aldehydes is described. It was found that acylated 3-spirocyclobutyl oxindoles were generated from the coupling of BCB-amides and aromatic aldehydes, while reactions gave exclusively decarbonylative alkylarylation products using alkyl aldehydes as radical precursors.

4.
J Org Chem ; 89(16): 11233-11243, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39052929

RESUMEN

A visible-light-induced radical cascade regioselective acylation/cyclization of 1,7-dienes with acyl oxime esters for the preparation of acylation polycyclic compounds via NCR-mediated C-C σ-bond cleavage is established. The transformation involves the cleavage of the C-C σ-bond in acyl oxime esters and selective addition of the electron neutral C═C bonds in 1,7-dienes for the synthesis of acyl polycyclic quinolinone derivatives, not the traditional seven-membered ring products. The strategy offers several advantages, including broad substrate tolerance, no need for bases, hyperstoichiometric radical initiators, and other auxiliaries.

5.
J Exerc Sci Fit ; 22(4): 341-349, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39022666

RESUMEN

Objective: This study aims to systematically assess physical exercise-related symptoms of post-acute sequelae of SARS-CoV-2 infection (PASC or long COVID) in coronavirus disease 2019 (COVID-19) survivors. Methods: Eight databases were systematically searched on March 03, 2024. Original studies that compared physical exercise-related parameters measured by exercise testing between COVID-19 survivors who recovered from SARS-CoV-2 infection over 3 months and non-COVID-19 controls were included. A random-effects model was utilized to determine the mean differences (MDs) or standardized MDs in the meta-analysis. Results: A total of 40 studies with 6241 COVID-19 survivors were included. The 6-min walk test, maximal oxygen consumption (VO2max), and anaerobic threshold were impaired in COVID-19 survivors 3 months post-infection compared with non-COVID-19 controls in exercise testing, while VO2 were comparable between the two groups at rest. In contrast, no differences were observed in SpO2, heart rate, blood pressure, fatigue, and dyspnea between COVID-19 survivors and non-COVID-19 controls in exercise testing. Conclusion: The findings suggest an underestimation of the manifestations of PASC. COVID-19 survivors also harbor physical exercise-related symptoms of PASC that can be determined by the exercise testing and are distinct from those observed at rest. Exercise testing should be included while evaluating the symptoms of PASC in COVID-19 survivors.

6.
J Org Chem ; 89(12): 8721-8733, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38832808

RESUMEN

A novel strategy for the difunctionalization of electron-deficient alkenes with aryl sulfonium salts to access remote sulfur-containing oxindole derivatives by using in situ-formed copper(I)-based complexes as a photoredox catalyst is presented. This method enables the generation of the C(sp3)-centered radicals through site selective cleavage of the C-S bond of aryl sulfonium salts under mild conditions. Moreover, the oxidation reactions of desired products provide a new strategy for the preparation of sulfoxide or sulfone-containing compounds. Importantly, this approach can be easily applied to late-stage modification of pharmaceuticals molecules.

7.
Front Bioeng Biotechnol ; 12: 1382085, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38572358

RESUMEN

In this study, a high-efficiency superparamagnetic drug delivery system was developed for preclinical treatment of bladder cancer in small animals. Two types of nanoparticles with magnetic particle imaging (MPI) capability, i.e., single- and multi-core superparamagnetic iron oxide nanoparticles (SPIONs), were selected and coupled with bladder anti-tumor drugs by a covalent coupling scheme. Owing to the minimal particle size, magnetic field strengths of 270 mT with a gradient of 3.2 T/m and 260 mT with a gradient of 3.7 T/m were found to be necessary to reach an average velocity of 2 mm/s for single- and multi-core SPIONs, respectively. To achieve this, a method of constructing an in vitro magnetic field for drug delivery was developed based on hollow multi-coils arranged coaxially in close rows, and magnetic field simulation was used to study the laws of the influence of the coil structure and parameters on the magnetic field. Using this method, a magnetic drug delivery system of single-core SPIONs was developed for rabbit bladder therapy. The delivery system consisted of three coaxially and equidistantly arranged coils with an inner diameter of Φ50 mm, radial height of 85 mm, and width of 15 mm that were positioned in close proximity to each other. CCK8 experimental results showed that the three types of drug-coupled SPION killed tumor cells effectively. By adjusting the axial and radial positions of the rabbit bladder within the inner hole of the delivery coil structure, the magnetic drugs injected could undergo two-dimensional delivery motions and were delivered and aggregated to the specified target location within 12 s, with an aggregation range of about 5 mm × 5 mm. In addition, the SPION distribution before and after delivery was imaged using a home-made open-bore MPI system that could realistically reflect the physical state. This study contributes to the development of local, rapid, and precise drug delivery and the visualization of this process during cancer therapy, and further research on MPI/delivery synchronization technology is planned for the future.

8.
J Org Chem ; 89(8): 5409-5422, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38563439

RESUMEN

An oxidant-assisted tandem sulfonylation/cyclization of electron-deficient alkenes with 4-alkyl-substituted Hantzsch esters and Na2S2O5 for the preparation of 3-alkylsulfonylated oxindoles under mild conditions in the absence of a photocatalyst and transition metal catalyst is established. The mechanism studies show that the alkyl radicals, which come from the cleavage of the C-C bond in 4-substituted Hantzsch esters under oxidant conditions, subsequently undergo the in situ insertion of sulfur dioxide to generate the crucial alkylsulfonyl radical intermediates. This three-component reaction provides an efficient and facile route for the construction of alkylsulfonylated oxindoles and avoids the use of highly toxic alkylsulfonyl chlorides or alkylsulfonyl hydrazines as alkylsulfonyl sources.

9.
Chem Commun (Camb) ; 60(36): 4834-4837, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38619398

RESUMEN

A convenient method for oxidant-promoted radical cascade acylation or decarbonylative alkylation of 1,7-dienes with aldehydes has been established. This method allows for the rapid construction of N-containing polycyclic skeletons in a highly regio- and stereoselective manner. This transformation provides a simple and efficient method for the preparation of a range of tetrahydro-6H-indeno[2,1-c]quinolinone derivatives by sequential formation of three new carbon-carbon bonds. Additionally, this radical cascade cyclization can selectively convert aldehydes into aroyl/primary aliphatic acyl radicals and secondary or tertiary alkyl radicals.

10.
Org Lett ; 26(18): 3756-3761, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38678581

RESUMEN

Phenazines, crucial constituents of nitrogen-containing heterocycles, widely exist in functional compounds. Herein, we report an anodic oxidative (4 + 2) cyclization between anilines and o-phenylenediamines for the uniform construction of phenazines in a simple undivided cell. Dual C-H amination followed by oxidation represents an outstanding step and atom efficiency. A sequence of phenazines is produced with excellent functional group tolerance at room temperature.

11.
Org Biomol Chem ; 22(18): 3752-3760, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38652536

RESUMEN

2-Aminobenzothiazoles are commonly encountered in various functional compounds. Herein, we disclose an electro-oxidative three-component reaction for the effective synthesis of 2-aminobenzothiazoles under mild conditions, utilizing non-toxic and abundant elemental sulfur as the sulfur source. Both aliphatic amines and aryl amines demonstrate good compatibility at room temperature, highlighting the broad functional group tolerance of this approach. Additionally, elemental selenium demonstrated reactivities comparable to those of elemental sulfur.

12.
Top Curr Chem (Cham) ; 382(1): 10, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38457062

RESUMEN

Organophosphorus compounds have long been considered valuable in both organic synthesis and life science. P(III)-nucleophiles, such as phosphites, phosphonites, and diaryl/alkyl phosphines, are particularly noteworthy as phosphorylation reagents for their ability to form new P-C bonds, producing more stable, ecofriendly, and cost-effective organophosphorus compounds. These nucleophiles follow similar phosphorylation routes as in the functionalization of P-H bonds and P-OH bonds. Activation can occur through photocatalytic, electrocatalytic, or thermo-driven reactions, often in coordination with a Michaelis-Arbuzov-trpe rearrangement process, to produce the desired products. As such, this review offers a thorough overview of the phosphorylated transformation and potential mechanisms of P(III)-nucleophiles, specifically focusing on developments since 2010. Notably, this review may provide researchers with valuable insights into designing and synthesizing functionalized organophosphorus compounds from P(III)-nucleophiles, guiding future advancements in both research and practical applications.


Asunto(s)
Compuestos Organofosforados , Fosfinas , Compuestos Organofosforados/química , Fosfinas/química , Técnicas de Química Sintética
13.
Org Lett ; 26(10): 2073-2078, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38446422

RESUMEN

A visible-light-induced radical alkylarylation of N-aryl bicyclobutyl amides with α-carbonyl alkyl bromides for the synthesis of functionalized 3-spirocyclobutyl oxindoles is described in which ß-selective radical addition of the alkyl radical to N-aryl bicyclobutyl amides forms a key radical intermediate followed by interception with intrinsic arene functional group. This approach can be applicable to a wide range of α-carbonyl alkyl bromides, including primary, secondary, and tertiary α-bromoalkyl esters, ketones, nitriles, and nitro compounds.

14.
J Org Chem ; 89(5): 3033-3048, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38372254

RESUMEN

A novel and efficient protocol for the synthesis of diarylallyl-functionalized phosphonates, phosphinates, and phosphine oxides through the zinc-catalyzed dehydroxylative phosphorylation of allylic alcohols with P(III)-nucleophiles via a Michaelis-Arbuzov-type rearrangement is reported. A broad range of allylic alcohols and P(III)-nucleophiles (P(OR)3, ArP(OR)2, and Ar2P(OR)) are well tolerated in this reaction, and the expected dehydroxylative phosphorylation products could be synthesized with good to excellent yields under the optimal reaction conditions. The reaction can be easily scaled up at a gram-synthesis level. Furthermore, through the step-by-step control experiments, kinetic study experiments, and 31P NMR tracking experiments, we acquired insights into the reaction and proposed the possible mechanism for this transformation.

15.
Org Biomol Chem ; 22(7): 1458-1465, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38282546

RESUMEN

A visible-light-induced radical cyclization reaction of o-vinylaryl isocyanides and oxime esters to access various 2,4-disubstituted quinolines was disclosed. Oxime esters were employed as acyl radical precursors via the carbon-carbon bond cleavage. It provided an effective way for the synthesis of 2-acyl-4-arlysubstituted quinolines under mild conditions and exhibited good functional group tolerance and substrate applicability.

16.
Small ; 20(4): e2306516, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37715101

RESUMEN

Antimony selenide (Sb2 Se3 ) is a highly promising photovoltaic material thanks to its outstanding optoelectronic properties, as well as its cost-effective and eco-friendly merits. However, toxic CdS is widely used as an electron transport layer (ETL) in efficient Sb2 Se3 solar cells, which largely limit their development toward market commercialization. Herein, an effective green Cd-free ETL of SnOx is introduced and deposited by atomic layer deposition method. Additionally, an important post-annealing treatment is designed to further optimize the functional layers and the heterojunction interface properties. Such engineering strategy can optimize SnOx ETL with higher nano-crystallinity, higher carrier density, and less defect groups, modify Sb2 Se3 /SnOx heterojunction with better interface performance and much desirable "spike-like" band alignment, and also improve the Sb2 Se3 light absorber layer quality with passivated bulk defects and prolonged carrier lifetime, and therefore to enhance carrier separation and transport while suppressing non-radiative recombination. Finally, the as-fabricated Cd-free Mo/Sb2 Se3 /SnOx /ITO/Ag thin-film solar cell exhibits a stimulating efficiency of 7.39%, contributing a record value for Cd-free substrate structured Sb2 Se3 solar cells reported to date. This work provides a viable strategy for developing and broadening practical applications of environmental-friendly Sb2 Se3 photovoltaic devices.

17.
Org Biomol Chem ; 22(3): 513-520, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38131384

RESUMEN

We herein report an efficient photoredox radical cyclization reaction of o-vinylaryl isocyanides with acyl chlorides to access a wide range of 2,4-disubstituted quinolines. Preliminary mechanism experiment results suggested that this reaction was initiated by an acyl radical generated from acyl chlorides through a single-electron-transfer (SET) process. This transformation showed good substrate suitability and functional group compatibility at room temperature.

18.
Clinics (Sao Paulo) ; 78: 100308, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38041986

RESUMEN

OBJECTIVES: Traumatic hemorrhagic shock is a major death-related factor contributing to mortality in emergencies and can be effectively handled by the Limited Fluid Resuscitation (LFR) method. In the current investigation, the authors analyzed the influence of different administrating blood pressure on the treatment outcomes of LFR. METHODS: 276 participants were enrolled in the current study retrospectively from January 2016 to December 2021 and were divided into three groups based on the administrating blood pressure of LFR. The difference among the three groups regarding serum levels of cytokines as well as blood hemodynamics parameters was analyzed. RESULTS: The results showed after the T2 stage treatment, cytokine levels in the three groups were all significantly influenced by different LFR strategies with medium MAP showing the strongest effects on the expression of all cytokine genes. Moreover, the MAP value was in positive correlation with IL-6, IL-10, and TNF-α levels, but showed no clear relation with IL-4 level in all three groups. Regarding the effects on hemodynamics parameters, the levels of CVP, CO, and CI were slightly increased by the different LFR administrating strategies, and the effect of medium and high MAP was statistically stronger than that of low MAP. CONCLUSION: The present results showed that LFR would influence serum inflammatory levels by improving blood hemodynamics parameters. Medium MAP showed the strongest improving effects with the least side effects, which can be employed as the optimal administrating strategy for LFR in the future.


Asunto(s)
Choque Hemorrágico , Humanos , Choque Hemorrágico/terapia , Estudios Retrospectivos , Hemodinámica , Citocinas , Resultado del Tratamiento , Fluidoterapia/métodos , Resucitación/métodos
19.
J Org Chem ; 88(23): 16196-16215, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37955519

RESUMEN

A simple and efficient method for the ruthenium-catalyzed 1,6-hydroalkylation of para-quinone methides (p-QMs) with ketones via the in situ activation of C(sp3)-H bonds has been disclosed. Without the need for preactivation of the substrates and oxidant, a broad range of p-QMs and ketones are well tolerated, producing the expected 1,6-hydroalkylation products with moderate to good yields. Step-by-step control experiments and DFT calculation were conducted systematically to gain insights for the plausible reaction mechanism. This finding may have potential application in the selective diarylmethylation of ketones at the α-C position in organic synthesis.

20.
Org Biomol Chem ; 22(1): 10-24, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38018531

RESUMEN

Cyclobutanone oximes and their derivatives are pivotal core structural motifs in organic chemistry. Iminyl-radical-triggered C-C bond cleavage of cyclobutanone oximes delivers an efficient strategy to produce stable distal cyano-substituted alkyl radicals, which can capture SO2, CO or O2 to form cyanoalkylsulfonyl radicals, cyanoalkylcarbonyl radicals or cyanoalkoxyl radicals under mild conditions. In the past several years, cyanoalkylsulfonylation/cyanoalkylcarbonyaltion/cyanoalkoxylation has attracted a lot of interest. In this updated report, the strategies for trapping SO2, CO or O2via iminyl-radical-triggered ring-opening of cyclobutanone oximes are summarized.

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