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1.
Jpn J Clin Oncol ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38941323

RESUMEN

BACKGROUND: Sarcopenic obesity (SO) affects outcomes in various malignancies. However, its clinical significance in patients undergoing neoadjuvant chemotherapy (NAC) for locally advanced gastric cancer (LAGC) remains unclear. This study investigated the impact of pre- and post-NAC SO on postoperative morbidity and survival. METHODS: Data from 207 patients with LAGC, who underwent NAC followed by radical gastrectomy between January 2010 and October 2019, were reviewed. Skeletal muscle mass and visceral fat area were measured pre- and post-NAC using computed tomography to define sarcopenia and obesity, the coexistence of which was defined as SO. RESULTS: Among the patients, 52 (25.1%) and 38 (18.4%) developed SO before and after NAC, respectively. Both pre- (34.6%) and post- (47.4%) NAC SO were associated with the highest postoperative morbidity rates; however, only post-NAC SO was an independent risk factor for postoperative morbidity [hazard ratio (HR) = 9.550, 95% confidence interval (CI) = 2.818-32.369; P < .001]. Pre-NAC SO was independently associated with poorer 3-year overall [46.2% vs. 61.3%; HR = 1.258 (95% CI = 1.023-1.547); P = .049] and recurrence-free [39.3% vs. 55.4%; HR 1.285 (95% CI 1.045-1.579); P = .017] survival. CONCLUSIONS: Pre-NAC SO was an independent prognostic factor in patients with LAGC undergoing NAC; post-NAC SO independently predicted postoperative morbidity.

2.
J Biol Chem ; 300(7): 107448, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38844135

RESUMEN

O-linked ß-N-acetylglucosamine (O-GlcNAc) transferase (OGT) is the sole enzyme that catalyzes all O-GlcNAcylation reactions intracellularly. Previous investigations have found that OGT levels oscillate during the cell division process. Specifically, OGT abundance is downregulated during mitosis, but the underlying mechanism is lacking. Here we demonstrate that OGT is ubiquitinated by the ubiquitin E3 ligase, anaphase promoting complex/cyclosome (APC/C)-cell division cycle 20 (Cdc20). We show that APC/CCdc20 interacts with OGT through a conserved destruction box (D-box): Arg-351/Leu-354, the abrogation of which stabilizes OGT. As APC/CCdc20-substrate binding is often preceded by a priming ubiquitination event, we also used mass spectrometry and mapped OGT Lys-352 to be a ubiquitination site, which is a prerequisite for OGT association with APC/C subunits. Interestingly, in The Cancer Genome Atlas, R351C is a uterine carcinoma mutant, suggesting that mutations of the D-box are linked with tumorigenesis. Paradoxically, we found that both R351C and the D-box mutants (R351A/L354A) inhibit uterine carcinoma in mouse xenograft models, probably due to impaired cell division and proliferation. In sum, we propose a model where OGT Lys-352 ubiquitination primes its binding with APC/C, and then APC/CCdc20 partners with OGT through the D-box for its mitotic destruction. Our work not only highlights the key mechanism that regulates OGT during the cell cycle, but also reveals the mutual coordination between glycosylation and the cell division machinery.

3.
Angew Chem Int Ed Engl ; : e202407307, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38868977

RESUMEN

Small organic photothermal reagents (PTAs) with absorption bands located in the second near-infrared (NIR-II, 1000-1700 nm) window are highly desirable for effectively combating deep-seated tumors. However, the rarely reported NIR-II absorbing PTAs still suffer from a low molar extinction coefficient (MEC, ε), inadequate chemostability and photostability, as well as the high light power density required during the therapeutic process. Herein, we developed a series of boron difluoride bridged azafulvene dimer acceptor-integrated small organic PTAs. The B-N coordination bonds in the π-conjugated azafulvene dimer backbone endow it the strong electron-withdrawing ability, facilitating the vigorous donor-acceptor-donor (D-A-D) structure PTAs with NIR-II absorption. Notably, the PTAs namely OTTBF shows high MEC (7.21× 104 M-1 cm-1), ultrahigh chemo- and photo-stability. After encapsulated into water-dispersible nanoparticles, OTTBF NPs can achieve remarkable photothermal conversion effect under 1064 nm irradiation with a light density as low as 0.7 W cm-2, which is the lowest reported NIR-II light power used in PTT process as we know. Furthermore, OTTBF NPs have been successfully applied for in vitro and in vivo deep-seated cancer treatments under 1064 nm laser. This study provides an insight into the future exploration of versatile D-A-D structured NIR-II absorption organic PTAs for biomedical applications.

4.
Sci Total Environ ; 941: 173724, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38844218

RESUMEN

The frost damage behavior of recycled aggregates concrete (RAC) in a cold region is inherently more complex due to the incorporation of recycled coarse aggregate (RCA). In real-world service environments, the combined effects of mechanical loading and environmental conditions further make RAC's damage mechanism more intricate. This study explores the impact of uniaxial compressive loading (at 0.1fc, 0.3fc, and 0.5fc, respectively), freeze-thaw cycles, and chloride penetration on the relative dynamic elastic modulus (RDEM), mass transport properties, and microstructure of RAC with varying RCA replacement ratios. The results indicate that specimens loaded at 0.3fc exhibit enhanced frost resistance, with reduced water absorption and chloride ion content. Additionally, a damage model is developed to quantify the effects of mechanical loading, freeze-thaw cycles, and chloride penetration on RDEM degradation. The investigation using X-ray computed tomography (X-CT), mercury intrusion porosimetry (MIP), and scanning electron microscopy (SEM) techniques reveals that as compressive stress levels increase, the microstructural density and porosity of RAC initially decrease before increasing. Moreover, the RDEM of RAC decreases with decreasing pore sphericity. Compared to the R100-S55 samples, the pore sphericity of R100-S55-0.5fc samples increased by 60.4 % in the range of 0.4-0.5, resulting in a decrease of approximately 17.72 % in the RDEM. Furthermore, the initial sorptivity of frost-damaged RAC exhibits a significant linear relationship with porosity. Overall, this study elucidates the evolving trends of mass transport properties and microstructure in RAC under loading and freeze-thaw conditions, laying a theoretical groundwork for the widespread application of RCA.

5.
Zhongguo Gu Shang ; 37(6): 5835-90, 2024 Jun 25.
Artículo en Chino | MEDLINE | ID: mdl-38910381

RESUMEN

OBJECTIVE: To compare clinical effect between open reduction and fixation with cannulated screw and threaded rivet via posteromedial approach versus arthroscopic Endobutton plate fixation in treating posterior cruciate ligament avulsion fractures. METHODS: Clinical data of 38 patients with posterior cruciate ligament avulsion fractures from July 2020 to December 2021 were analyzed retrospectively, and divided into open reduction and internal fixation group (posterior medial approach hollow anchor system fixation) and arthroscopic fixation group (Endobutton with loop plate fixation under arthroscopy). There were 20 patients in open reduction and internal fixation group, including 16 males and 4 females, aged from 26 to 74 years old with an average of (42.9±18.8) years old;13 patients on the left side and 7 patients on the right side;12 patients were classified to typeⅡand 8 patiens with type Ⅲ according to Meyers-McKeever fractures classification;14 patients were gradeⅡand 6 patients were grade Ⅲ in back drawer test. There were 18 patients in arthroscopic fixation group, including 11 males and 7 females;aged from 24 to 70 years old with an average of (53.5±13.4) years old;11 patients on the left side and 7 patients on the right side;10 patients were classified to typeⅡand 8 patiens with type Ⅲ according to Meyers-McKeever fractures classification;11 patients were gradeⅡand 7 patients were grade Ⅲ in back drawer test. Operation time, blood loss, and quality of immediate reduction were compared between two groups. Knee range of motion, knee back drawer test, and International Knee Documentation Committee(IKDC) grading, KT2000 stability evaluation and Lysholm function score of knee joint were compared at 6 months after operation. RESULTS: All patients were followed up for 8 to 16 months with an average of (12.3±1.9) months. There were no complications such as incision infection, fracture malunion or non-union, and internal fixation loosening occurred. The avulsion fractures of knee joint were reached to imaging healing standard at 6 months after operation. Operation time and blood loss in open reduction and internal fixation group were (56.4±7.1) min and (63.2±10.2) ml, while (89.9±7.4) min and (27.7±8.7) ml in arthroscopic fixation group, respectively, and had significant difference between two groups (P<0.05). There were no differences in immediate reduction quality (χ2=0.257, P=0.612), knee joint range of motion at 6 months after opertaion (t=0.492, P=0.626), knee joint rear drawer test ( χ2=0.320, P=0.572), IKDC classification of knee joint (χ2=0.127, P=0.938), KT2000 stability evaluation (χ2=0.070, P=0.791), and knee Lysholm function score (t=0.092, P=0.282) between two groups. CONCLUSION: Posterior medial approach with hollow anchoring system fixation and arthroscopic Endobutton with loop plate fixation for the treatment of posterior cruciate ligament tibial occlusion avulsion fracture could achieve satisfactory clinical results, and arthroscopic surgery has less bleeding, but also has a longer learning curve and longer operation time than traditional incision surgery. The surgeon needs to make a choice according to clinical situation of patient and their own surgical inclination.


Asunto(s)
Artroscopía , Placas Óseas , Fijación Interna de Fracturas , Ligamento Cruzado Posterior , Humanos , Masculino , Femenino , Persona de Mediana Edad , Artroscopía/métodos , Adulto , Anciano , Ligamento Cruzado Posterior/cirugía , Ligamento Cruzado Posterior/lesiones , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/instrumentación , Estudios Retrospectivos , Fracturas por Avulsión/cirugía , Clavos Ortopédicos
6.
J Chem Phys ; 160(24)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38912624

RESUMEN

This Special Issue of the Journal of Chemical Physics is dedicated to the work and life of John P. Perdew. A short bio is available within the issue [J. P. Perdew, J. Chem. Phys. 160, 010402 (2024)]. Here, we briefly summarize key publications in density functional theory by Perdew and his collaborators, followed by a structured guide to the papers contributed to this Special Issue.

7.
Bioact Mater ; 37: 299-312, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38694765

RESUMEN

Ultrahigh dose-rate (FLASH) radiotherapy is an emerging technology with excellent therapeutic effects and low biological toxicity. However, tumor recurrence largely impede the effectiveness of FLASH therapy. Overcoming tumor recurrence is crucial for practical FLASH applications. Here, we prepared an agarose-based thermosensitive hydrogel containing a mild photothermal agent (TPE-BBT) and a glutaminase inhibitor (CB-839). Within nanoparticles, TPE-BBT exhibits aggregation-induced emission peaked at 900 nm, while the unrestricted molecular motions endow TPE-BBT with a mild photothermy generation ability. The balanced photothermal effect and photoluminescence are ideal for phototheranostics. Upon 660-nm laser irradiation, the temperature-rising effect softens and hydrolyzes the hydrogel to release TPE-BBT and CB-839 into the tumor site for concurrent mild photothermal therapy and chemotherapy, jointly inhibiting homologous recombination repair of DNA. The enhanced FLASH radiotherapy efficiently kills the tumor tissue without recurrence and obvious systematic toxicity. This work deciphers the unrestricted molecular motions in bright organic fluorophores as a source of photothermy, and provides novel recurrence-resistant radiotherapy without adverse side effects.

8.
Biophys Rep ; 10(1): 15-21, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38737474

RESUMEN

Tumor metastasis, responsible for approximately 90% of cancer-associated mortality, remains poorly understood. Here in this study, we employed a melanoma lung metastasis model to screen for metastasis-related genes. By sequential tail vein injection of mouse melanoma B16F10 cells and the subsequently derived cells from lung metastasis into BALB/c mice, we successfully obtained highly metastatic B16F15 cells after five rounds of in vivo screening. RNA-sequencing analysis of B16F15 and B16F10 cells revealed a number of differentially expressed genes, some of these genes have previously been associated with tumor metastasis while others are novel discoveries. The identification of these metastasis-related genes not only improves our understanding of the metastasis mechanisms, but also provides potential diagnostic biomarkers and therapeutic targets for metastatic melanoma.

9.
Angew Chem Int Ed Engl ; 63(29): e202404142, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38715431

RESUMEN

Fluorescent imaging and biosensing in the near-infrared-II (NIR-II) window holds great promise for non-invasive, radiation-free, and rapid-response clinical diagnosis. However, it's still challenging to develop bright NIR-II fluorophores. In this study, we report a new strategy to enhance the brightness of NIR-II aggregation-induced emission (AIE) fluorophores through intramolecular electrostatic locking. By introducing sulfur atoms into the side chains of the thiophene bridge in TSEH molecule, the molecular motion of the conjugated backbone can be locked through intramolecular interactions between the sulfur and nitrogen atoms. This leads to enhanced NIR-II fluorescent emission of TSEH in both solution and aggregation states. Notably, the encapsulated nanoparticles (NPs) of TSEH show enhanced brightness, which is 2.6-fold higher than TEH NPs with alkyl side chains. The in vivo experiments reveal the feasibility of TSEH NPs in vascular and tumor imaging with a high signal-to-background ratio and precise resection for tiny tumors. In addition, polystyrene nanospheres encapsulated with TSEH are utilized for antigen detection in lateral flow assays, showing a signal-to-noise ratio 1.9-fold higher than the TEH counterpart in detecting low-concentration antigens. This work highlights the potential for developing bright NIR-II fluorophores through intramolecular electrostatic locking and their potential applications in clinical diagnosis and biomedical research.


Asunto(s)
Colorantes Fluorescentes , Rayos Infrarrojos , Imagen Óptica , Electricidad Estática , Colorantes Fluorescentes/química , Humanos , Nanopartículas/química , Tiofenos/química , Animales , Ratones , Estructura Molecular
10.
PLoS One ; 19(5): e0300181, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38776341

RESUMEN

Herein, the spatial evolution characteristics of high-level Grade A tourist attractions in the Yangtze River Delta (YRD) urban agglomeration, from 2001 to 2021, are studied by comprehensively applying the nearest neighbor index, kernel density analysis, standard deviation ellipse, and spatial autocorrelation. High-level Grade A tourist attractions are investigated using the random forest model as the driving mechanism of the spatial pattern. Results show that 1) the spatial distribution of high-level Class A tourist attractions in the YRD city cluster has grown to be an agglomeration, and the high-density areas have evolved from "point-like dispersion to regiment-like combination," gradually forming a B-shaped core density structure. 2) The spatial distribution comprises an overall "northwest-southeast" direction, a small counterclockwise rotation, the distribution of the center of gravity to the southwest migration, and the center of gravity from the territory of Suzhou City to the territory of Huzhou City. 3) The high-level Class A tourist attractions in the YRD city cluster as a whole show a strong positive spatial correlation, and the significantly clustered areas include three types: high-high (H-H), low-low (L-L), and low-high (L-H). 4) The spatial distribution of high, A-level tourist attractions in the YRD city cluster results from the combined action of the natural environment, resource endowment, socioeconomy, and policy background. Each element has a nonlinear and complex influence on the distribution of scenic spots.


Asunto(s)
Ciudades , Ríos , China , Humanos , Turismo , Análisis Espacio-Temporal
11.
Org Lett ; 26(20): 4194-4199, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38747692

RESUMEN

A photoredox-catalyzed sequential α-formyl/carboxylation of alkenes with glyoxylic acid acetals and CO2 has been developed to afford a range of masked γ-formyl esters in good yields, which could be readily transformed into diverse compounds, such as γ-formyl ester, hemiacetal, and 1,4-diol. This reaction features mild conditions, readily available starting materials, and operational simplicity.

12.
Small ; : e2401334, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38804884

RESUMEN

Lung cancer, a highly prevalent and lethal form of cancer, is often associated with oxidative stress. Photodynamic therapy (PDT) has emerged as a promising alternative therapeutic tool in cancer treatments, but its efficacy is closely correlated to the photosensitizers generating reactive oxygen species (ROS) and the antioxidant capacity of tumor cells. In particular, glutathione (GSH) can reduce the ROS and thus compromise PDT efficacy. In this study, a GSH-responsive near-infrared photosensitizer (TBPPN) based on aggregation-induced emission for real-time monitoring of GSH levels and enhanced PDT for lung cancer treatment is developed. The strategic design of TBPPN, consisting of a donor-acceptor structure and incorporation of dinitrobenzene, enables dual functionality by not only the fluorescence being activated by GSH but also depleting GSH to enhance the cytotoxic effect of PDT. TBPPN demonstrates synergistic PDT efficacy in vitro against A549 lung cancer cells by specifically targeting different cellular compartments and depleting intracellular GSH. In vivo studies further confirm that TBPPN can effectively inhibit tumor growth in a mouse model with lung cancer, highlighting its potential as an integrated agent for the diagnosis and treatment of lung cancer. This approach enhances the effectiveness of PDT for lung cancer and deserves further exploration of its potential for clinical application.

13.
Heliyon ; 10(9): e30678, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38765127

RESUMEN

Cellular Automaton (CA) is widely used because of its ability to simulate complex spatiotemporal dynamic processes through applying simple rules. The basis of the CA model is the definition of transformation rules. During a simulation process, the rules determine the change of the cell state. However, existing processing methods calculate the driving factors based on single-point time (start time or end time), making it difficult to reflect the fact that numerous driving factors affecting the cell conversion dynamically change with time. Based on the time dynamics perspective and the data set of multiple time series, this paper designs a method of dynamic adjustment of driving factors of urban expansion on the local cell-scale. It uses linear, exponential, logarithmic, and polynomial fitting to develop a CA model of dynamic adjustment that conforms to the characteristics of local spatial evolution. The main conclusions of the paper are as follows: (1) The polynomial fitting has the highest average R2, indicating that the driving factors experiences large fluctuations over time; (2) Secondly, the simulation result kappa obtained by the four fitting methods is between 0.781-0.810, which is higher than the simulation accuracy obtained by using only a single time point. In other words, the factor does not dynamically fit with time and (3) The fitting accuracy of road density is a key indicator of correct and incorrect simulation parts of construction land. Our results demonstrate that the precision of the CA model may be significantly improved by capturing the time development law of environmental variables affecting urban development at the micro-scale.

14.
Front Bioeng Biotechnol ; 12: 1351787, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38562672

RESUMEN

Nanotechnology is revolutionising different areas from manufacturing to therapeutics in the health field. Carbon nanotubes (CNTs), a promising drug candidate in nanomedicine, have attracted attention due to their excellent and unique mechanical, electronic, and physicochemical properties. This emerging nanomaterial has attracted a wide range of scientific interest in the last decade. Carbon nanotubes have many potential applications in cancer therapy, such as imaging, drug delivery, and combination therapy. Carbon nanotubes can be used as carriers for drug delivery systems by carrying anticancer drugs and enabling targeted release to improve therapeutic efficacy and reduce adverse effects on healthy tissues. In addition, carbon nanotubes can be combined with other therapeutic approaches, such as photothermal and photodynamic therapies, to work synergistically to destroy cancer cells. Carbon nanotubes have great potential as promising nanomaterials in the field of nanomedicine, offering new opportunities and properties for future cancer treatments. In this paper, the main focus is on the application of carbon nanotubes in cancer diagnostics, targeted therapies, and toxicity evaluation of carbon nanotubes at the biological level to ensure the safety and real-life and clinical applications of carbon nanotubes.

15.
Angew Chem Int Ed Engl ; 63(28): e202401261, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38687258

RESUMEN

Aggregation is a conventional method to enhance the quantum yields (QYs) of pure organic luminophores due to the restriction of intramolecular motions (RIM). However, how to realize RIM in metal-organic frameworks (MOFs) is still unclear and challenging. In this work, the ligand meta-anchoring strategy is first proposed and proved to be an effective and systematic approach to restrict the intramolecular motions of MOFs for the QY improvement. By simply shifting the substituent position in the ligand from para to meta, the QY of the resulting MOF is significantly enhanced by eleven-fold. The value is even higher than that of ligand aggregates, demonstrating the strong RIM effect of this ligand meta-anchoring strategy. The introduction of co-ligand induces the appearance of visible yellow room temperature phosphorescence with a lifetime of 222 ms due to the QY enhancement and the charge transfer between the donor and accepter units. The present work thus broadens the understanding of the RIM mechanism from a new perspective, develops a novel method to realize RIM and expands the applicable objects from pure organic materials to organic-inorganic hybrid materials.

16.
J Chem Phys ; 160(13)2024 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-38557836

RESUMEN

VO2 is renowned for its electric transition from an insulating monoclinic (M1) phase, characterized by V-V dimerized structures, to a metallic rutile (R) phase above 340 K. This transition is accompanied by a magnetic change: the M1 phase exhibits a non-magnetic spin-singlet state, while the R phase exhibits a state with local magnetic moments. Simultaneous simulation of the structural, electric, and magnetic properties of this compound is of fundamental importance, but the M1 phase alone has posed a significant challenge to the density functional theory (DFT). In this study, we show none of the commonly used DFT functionals, including those combined with on-site Hubbard U to treat 3d electrons better, can accurately predict the V-V dimer length. The spin-restricted method tends to overestimate the strength of the V-V bonds, resulting in a small V-V bond length. Conversely, the spin-symmetry-breaking method exhibits the opposite trends. Each of these two bond-calculation methods underscores one of the two contentious mechanisms, i.e., Peierls lattice distortion or Mott localization due to electron-electron repulsion, involved in the metal-insulator transition in VO2. To elucidate the challenges encountered in DFT, we also employ an effective Hamiltonian that integrates one-dimensional magnetic sites, thereby revealing the inherent difficulties linked with the DFT computations.

17.
Chem Sci ; 15(11): 3893-3900, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38487218

RESUMEN

Compared with well-developed construction of Csp2-Csp2 atropisomers, the synthesis of Csp2-N atropisomers remains in its infancy, which is recognized as both appealing and challenging. Herein, we achieved the first organocatalyzed asymmetric synthesis of Csp2-N atropisomers by formal Csp2-O amination. With the aid of a suitable acid, 3-alkynyl-3-hydroxyisoindolinones reacted smoothly with 1-methylnaphthalen-2-ols to afford a wide range of atropisomers by selective formation of the Csp2-N axis. Particularly, both the kinetic (Z)-products and the thermodynamic (E)-products could be selectively formed. Furthermore, the rarely used combination of two chiral Brønsted acid catalysts achieved excellent enantiocontrol, which is intriguing and unusual in organocatalysis. Based on control experiments and DFT calculations, a cascade dehydration/addition/rearrangement process was proposed. More importantly, this work provided a new plat-form for direct atroposelective construction of the chiral Csp2-N axis.

18.
Acta Biochim Biophys Sin (Shanghai) ; 56(3): 427-439, 2024 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-38327186

RESUMEN

Mitochondrial homeostasis plays a pivotal role in oocyte maturation and embryonic development. Deoxyguanosine kinase (DGUOK) is a nucleoside kinase that salvages purine nucleosides in mitochondria and is critical for mitochondrial DNA replication and homeostasis in non-proliferating cells. Dguok loss-of-function mutations and deletions lead to hepatocerebral mitochondrial DNA deletion syndrome. However, its potential role in reproduction remains largely unknown. In this study, we find that Dguok knockout results in female infertility. Mechanistically, DGUOK deficiency hinders ovarian development and oocyte maturation. Moreover, DGUOK deficiency in oocytes causes a significant reduction in mitochondrial DNA copy number and abnormal mitochondrial dynamics and impairs germinal vesicle breakdown. Only few DGUOK-deficient oocytes can extrude their first polar body during in vitro maturation, and these oocytes exhibit irregular chromosome arrangements and different spindle lengths. In addition, DGUOK deficiency elevates reactive oxygen species levels and accelerates oocyte apoptosis. Our findings reveal novel physiological roles for the mitochondrial nucleoside salvage pathway in oocyte maturation and implicate DGUOK as a potential marker for the diagnosis of female infertility.


Asunto(s)
Infertilidad Femenina , Enfermedades Mitocondriales , Fosfotransferasas (Aceptor de Grupo Alcohol) , Humanos , Embarazo , Ratones , Femenino , Animales , Infertilidad Femenina/genética , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Mitocondrias/genética , Mitocondrias/metabolismo , Oocitos/metabolismo , Fertilidad/genética
19.
J Chem Phys ; 160(6)2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38341785

RESUMEN

The enigmatic mechanism underlying unconventional high-temperature superconductivity, especially the role of lattice dynamics, has remained a subject of debate. Theoretical insights have long been hindered due to the lack of an accurate first-principles description of the lattice dynamics of cuprates. Recently, using the r2SCAN meta-generalized gradient approximation (meta-GGA) functional, we have been able to achieve accurate phonon spectra of an insulating cuprate YBa2Cu3O6 and discover significant magnetoelastic coupling in experimentally interesting Cu-O bond stretching optical modes [Ning et al., Phys. Rev. B 107, 045126 (2023)]. We extend this work by comparing Perdew-Burke-Ernzerhof and r2SCAN performances with corrections from the on-site Hubbard U and the D4 van der Waals (vdW) methods, aiming at further understanding on both the materials science side and the density functional side. We demonstrate the importance of vdW and self-interaction corrections for accurate first-principles YBa2Cu3O6 lattice dynamics. Since r2SCAN by itself partially accounts for these effects, the good performance of r2SCAN is now more fully explained. In addition, the performances of the Tao-Mo series of meta-GGAs, which are constructed in a different way from the strongly constrained and appropriately normed (SCAN) meta-GGA and its revised version r2SCAN, are also compared and discussed.

20.
J Org Chem ; 89(4): 2683-2690, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38314706

RESUMEN

This report investigates the mechanism of photochemical Povarov-type reactions of N,N-dialkylanilines and maleimides in polar solvents (DMF or dioxane) in the presence of light. Fundamental aspects of the electron donor-acceptor (EDA) photoactivation pathway proposed to underpin this chemistry are examined through integrated experimental and computational studies. This approach provided evidence supporting the involvement of an EDA complex in facilitating this chemistry via a reaction mechanism that does not involve a triplet manifold. Most notably, our findings indicate that relying solely on UV-vis absorption spectroscopic data to either account for or predict reactivity in synthetic experiments may not always provide the complete picture. More specifically, this relates to considering UV-vis absorption spectroscopic data, calculated values for association constants (KEDA) and molar extinction coefficients (ε), with the reactivity observed in associated synthetic reactions in practice.

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