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1.
Clin Chim Acta ; 564: 119924, 2025 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-39153654

RESUMEN

Gitelman syndrome (GS) is the most prevalent genetic tubulopathy characterized by several electrolyte abnormalities, including hypokalemia, hypomagnesemia, hypocalciuria, metabolic alkalosis, and hyperreninemic hyperaldosteronism. These features are caused by a bi-allelic mutation in the SLC12A3 gene. In this report, we present a case of GS in an asymptomatic woman who incidentally exhibited hypokalemia during an antenatal check-up. Her biochemical profile was consistent with GS. Genetic analysis revealed two heterozygous variants in trans, namely, NM_001126108.2:c.625C>T; p.(Arg209Trp) and c.965C>T; p.(Ala322Val). The c.625C>T; p.(Arg209Trp) variant has previously been experimentally confirmed as a loss-of-function (LOF) variant. However, the functional impact of the c.965C>T variant, located at the 5 prime end of exon 8, has not been fully elucidated. Through the utilization of both complementary DNA (cDNA) and minigene analysis, we confirmed that the c.965C>T variant can generate two distinct cDNA transcripts. The first transcript carries a missense mutation, p.(Ala322Val) in the full SLC12A3 transcript, while the second transcript consists of an in-frame deletion of both exons 7 and 8 in the SLC12A3 transcript, in which may result in the loss of transmembrane regions 5 - 6 involved in chloride transport. Our findings provide insights into the intricate mechanisms of splicing, highlighting how a variant in one exon can remotely influence the transcription of an upstream exon, as observed with the variant in exon 8 impacting the transcription of exon 7.


Asunto(s)
Síndrome de Gitelman , Mutación Missense , Miembro 3 de la Familia de Transportadores de Soluto 12 , Síndrome de Gitelman/genética , Humanos , Miembro 3 de la Familia de Transportadores de Soluto 12/genética , Femenino , Empalme del ARN/genética , Adulto
2.
Front Cardiovasc Med ; 11: 1433011, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39399511

RESUMEN

Background: Cardiopulmonary bypass (CPB) triggers a strong inflammatory response in cardiovascular surgery patients during the perioperative period. This article mainly focuses on the perioperative application of novel inflammatory biomarkers in cardiovascular surgeries involving CPB. Methods: Patients were divided into a CPB group and a non-CPB group according to whether they underwent CPB during cardiovascular surgery. Novel inflammatory biomarkers and clinical results were recorded. The neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), platelet × neutrophil/lymphocyte ratio (SII), and monocyte × platelet × neutrophil/lymphocyte ratio (PIV) were calculated. The primary outcomes were perioperative prognosis between the CPB and non-CPB groups. The secondary outcomes included perioperative alterations of novel inflammatory biomarkers in the CPB group and predictive values of novel inflammatory biomarkers for postoperative infection and acute kidney injury. Results: A total of 332 patients were initially included in the study. Before propensity score matching (PSM), there were 96 patients in the CPB group and 236 patients in the non-CPB group. After PSM, both groups included 58 patients each. Compared with the non-CPB group, the CPB group had a higher proportion of intraoperative transfusion of blood products (63.79% vs. 6.90%, P < 0.001), specifically for red blood cells (58.62% vs. 3.45%, P < 0.001) and plasma (41.38% vs. 1.72, P < 0.001), exhibited a higher drainage fluid volume within 24 h [380 (200-550) ml vs. 200 (24-330) ml, P = 0.002], and required longer durations of mechanical ventilation [14.3 (6.6-21.3) h vs. 5.75 (4.08-10.1) h, P < 0.001] and ICU stay [48.78 (44.92-89.38) h vs. 27.16 (21.67-46.25) h, P < 0.001]. After surgery, NLR [14.00 (9.93-23.08) vs. 11.55 (7.38-17.38), P = 0.043] was higher in the CPB group, while the PIV, PLR, and SII in the CPB group were lower than those in the non-CPB group on the first day after surgery. Conclusions: Cardiovascular surgeries involving CPB exhibit a poorer prognosis compared to non-CPB procedures. Novel inflammatory biomarkers, including PLR, PIV, and SII, may offer valuable insights into the degree of postoperative inflammation, with NLR emerging as a potentially reliable prognostic indicator.

3.
Chembiochem ; : e202400688, 2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39417610

RESUMEN

The severe acute respiratory syndrome virus 2 (SARS-CoV-2) seriously impacted public health. The evolutionarily conserved viral chymotrypsin-like main protease (Mpro) is an important target for anti-SARS-CoV-2 drug development. Previous studies have shown that the eight N-terminal amino acids (N8) of SARS-CoV Mpro are essential for its dimerization, and are used to design inhibitors against SARS-CoV Mpro dimerization. Here, we established a simple readout assay using SDS-PAGE and Coomassie blue staining to measure inhibitory activity of N8 peptide derived from SARS-CoV-2 Mpro. To optimize its inhibitory effect, we then modified the side-chain length, charge, and hydrophilicity of the N8 peptide, and introduced a mutated Mpro recognition sequence. As a result, we obtained a series of potent peptide inhibitors against SARS-CoV-2 Mpro, with N8-A24 being the most efficient with an IC50 value of 1.44 mM. We observed that N8-A24 reduced Mpro dimerization with an IC50 value of 0.86 mM. Molecular docking revealed that N8-A24 formed hydrogen bond interactions with critical dimeric interface residues, thus inhibiting its dimerization and activity. In conclusion, our study not only discovers a series of peptide inhibitors targeting the SARS-CoV-2 Mpro dimerization, but also provides a promising strategy for the rational design of new inhibitors against COVID-19.

4.
Transl Lung Cancer Res ; 13(9): 2424-2434, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39430328

RESUMEN

Background: The benefit of adjuvant therapy remains controversial in completely resected (R0) stage IB non-small cell lung cancer (NCLSC) patients. In this study, we aimed to explore potential prognostic factors in stage IB NSCLC patients. Methods: This study included 215 patients with R0 stage IB lung adenocarcinoma (LUAD) (tumor size: 3-4 cm). DNA sequencing was performed with surgical samples of 126 patients using a panel of 9 driver genes. The molecular risk stratification was assessed by a 14-gene quantitative polymerase chain reaction assay. Results: Among the 215 patients, 67.9% had micropapillary/solid (MIP/SOL)-predominant tumors. Epidermal growth factor receptor (EGFR) mutations were detected in 75 of 126 patients (59.5%). MIP/SOL tumors harbored less common EGFR mutations than the other histologic patterns (50.6% vs. 79.5%, P=0.003). Molecular risk stratification was successfully assessed in 99 patients, of whom 37.4%, 26.3%, and 36.4% were high, intermediate, and low risk, respectively. The MIP/SOL pattern was associated with shorter disease-free survival (DFS) [hazard ratio (HR) =2.16, 95% confidence interval: 1.28-3.67; P=0.01]. The molecular high-risk patients had shorter DFS than the low- (HR =2.93, P=0.01) and intermediate-risk patients (HR =2.35, P=0.06). The prognostic value of molecular risk stratification was also significant in the MIP/SOL subset (median DFS high-risk: 45 months, low and intermediate risk: not reached; P=0.03). Conclusions: Our study showed that both the MIP/SOL pattern and molecular high-risk category were adverse prognostic factors in stage IB NSCLC patients. Our results suggest that combining histologic classification and molecular risk stratification may help to identify the subset of patients with poor prognosis.

5.
Proc Natl Acad Sci U S A ; 121(43): e2308684121, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39388277

RESUMEN

The aqueous alteration of the oceanic lithosphere provides significant energy that impacts the synthesis and diversity of organic compounds, which are crucial for the deep carbon cycle and may have provided the first building blocks for life. Although abiotic organic synthesis has been documented in mantle-derived rocks, the formation mechanisms and complexity of organic compounds in crustal rocks remain largely unknown. Here, we show the specific association of aliphatic carbonaceous matter with Fe oxyhydroxides in mafic crustal rocks of the Southwest Indian Ridge (SWIR). We determine potential Fe-based pathways for abiotic organic synthesis from CO2 and H2 using multimodal and molecular nano-geochemical tools. Quantum mechanical modeling is further employed to constrain the catalytical activity of Fe oxyhydroxides, revealing that the catalytic cycle of hydrogen may play a key role in carbon-carbon bond formation. This approach offers the possibility of interpreting physicochemical organic formation and condensation mechanisms at an atomic scale. The findings expand our knowledge of the existence of abiotic organic carbon in the oceanic crustal rocks and emphasize the mafic oceanic crust of the SWIR as a potential site for low-temperature abiotic organic synthesis.

6.
Mol Breed ; 44(9): 59, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39263271

RESUMEN

The stigma exsertion rate (SER) is a key trait for the outcrossing ability of hybrid rice, which directly affects the yield of hybrid seeds in hybrid seed production. In previous studies, we have located 18 QTLs for SER using single-segment substitution lines in rice. In this study, we found that 4 of 18 QTLs for SER controlled stigma size (SS). On chromosome 1, a QTL qSL-1 controlling stigma length (SL) was located at the same interval of qSER-1b. On chromosome 2, two QTLs for SS, qSS-2a and qSS-2b, linked closely within a 1288.0 kb region, were at the same positions of qSER-2a and qSER-2b, respectively. A QTL qSL-12 controlling SL on chromosome 12 was at the same location of qSER-12. Additive effects of four QTLs for SS ranged from 0.12 mm to 0.38 mm, showing significant effects on SS. In pyramiding lines of QTLs for SS, SS enlarged with the increase of QTLs. The effect of QTLs on SER was consistent with their effect on SS, and SL had a greater positive effect on SER than the stigma width. Our findings demonstrate that SS is one of the important factors affecting SER in rice. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-024-01499-0.

7.
bioRxiv ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39091829

RESUMEN

The final and rate-limiting enzyme in pyrimidine biosynthesis, CTP synthase (CTPS) , is essential for the viability of Mycobacterium tuberculosis and other mycobacteria. Its product, CTP, is critical for RNA, DNA, lipid and cell wall synthesis, and is involved in chromosome segregation. In various organisms across the tree of life, CTPS assembles into higher-order filaments, leading us to hypothesize that M. tuberculosis CTPS (mtCTPS) also forms higher-order structures. Here, we show that mtCTPS does assemble into filaments but with an unusual architecture not seen in other organisms. Through a combination of structural, biochemical, and cellular techniques, we show that polymerization stabilizes the active conformation of the enzyme and resists product inhibition, potentially allowing for the highly localized production of CTP within the cell. Indeed, CTPS filaments localize near the CTP-dependent complex needed for chromosome segregation, and cells expressing mutant enzymes unable to polymerize are altered in their ability to robustly form this complex. Intriguingly, mutants that alter filament formation are under positive selection in clinical isolates of M. tuberculosis, pointing to a critical role needed to withstand pressures imposed by the host and/or antibiotics. Taken together, our data reveal an unexpected mechanism for the spatially organized production of a critical nucleotide in M. tuberculosis, which may represent a vulnerability of the pathogen that can be exploited with chemotherapy.

8.
Int Immunopharmacol ; 140: 112817, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39116499

RESUMEN

BACKGROUND: Adenomyosis is a common gynecological disease, characterized by overgrowth of endometrial glands and stroma in the myometrium, however its exact pathophysiology still remains uncertain. Emerging evidence has demonstrated the elevated level of arginase 2 (ARG2) in endometriosis and adenomyosis. This study aimed to determine whether ARG2 involved in mitochondrial function and epithelial to mesenchymal transition (EMT) in adenomyosis and its potential underlying mechanisms. MATERIALS AND METHODS: RNA interference was used to inhibit ARG2 gene, and then Cell Counting Kit (CCK-8) assay and flow cytometery were performed to detect the cell proliferation capacity, cell cycle, and apoptosis progression, respectively. The mouse adenomyosis model was established and RT-PCR, Western blot analysis, mitochondrial membrane potential (Δψm) detection and mPTP opening evaluation were conducted. RESULTS: Silencing ARG2 effectively down-regulated its expression at the mRNA and protein levels in endometrial cells, leading to decreased enzyme activity and inhibition of cell viability. Additionally, ARG2 knockdown induced G0/G1 cell cycle arrest, promoted apoptosis, and modulated the expression of cell cycle- and apoptosis-related regulators. Notably, the interference with ARG2 induces apoptosis by mitochondrial dysfunction, ROS production, ATP depletion, decreasing the Bcl-2/Bax ratio, releasing Cytochrome c, and increasing the expression of Caspase-9/-3 and PARP. In vivo study in a mouse model of adenomyosis demonstrated also elevated levels of ARG2 and EMT markers, while siARG2 treatment reversed EMT and modulated inflammatory cytokines. Furthermore, ARG2 knockdown was found to modulate the NF-κB and Wnt/ß-catenin signaling pathways in mouse adenomyosis. CONCLUSION: Consequently, ARG2 silencing could induce apoptosis through a mitochondria-dependent pathway mediated by ROS, and G0/G1 cell cycle arrest via suppressing NF-κB and Wnt/ß-catenin signaling pathways in Ishikawa cells. These findings collectively suggest that ARG2 plays a crucial role in the pathogenesis of adenomyosis and may serve as a potential target for therapeutic intervention.


Asunto(s)
Adenomiosis , Apoptosis , Arginasa , Mitocondrias , FN-kappa B , Vía de Señalización Wnt , Animales , Femenino , Humanos , Ratones , Adenomiosis/genética , Adenomiosis/patología , Adenomiosis/metabolismo , Apoptosis/genética , Línea Celular , Proliferación Celular , Modelos Animales de Enfermedad , Endometrio/patología , Endometrio/metabolismo , Transición Epitelial-Mesenquimal , Puntos de Control de la Fase G1 del Ciclo Celular , Técnicas de Silenciamiento del Gen , Potencial de la Membrana Mitocondrial , Mitocondrias/metabolismo , FN-kappa B/metabolismo , Arginasa/genética , Arginasa/metabolismo
9.
Sci Rep ; 14(1): 19567, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39174794

RESUMEN

The ceiling structure in a long-narrow space has a significant impact on the thickness of the fire smoke layer. This paper mainly studies the influence of the height of the ceiling structure on the thickness of the smoke layer before the ceiling structure. Firstly, a theoretical analysis is conducted on the relationship between the critical thickness that affects the smoke flow state and the smoke layer thickness directly below the ceiling structure, and a formula for calculating the smoke layer thickness under gradient flow conditions is derived. Then a small-scale experimental platform was built to study the deviation of actual fire smoke relative to theoretical calculations. Experimental results show that due to the smoke cannot maintain gradient flow when crossing the ceiling structure, there is difference with theoretical calculations in the smoke layer thickness directly below the ceiling structure and some distance before the ceiling structure (which may be of greater concern for personnel evacuation). The gradient flow coefficient and thickness coefficient are defined to represent the above differences. After analysis, it was found that the gradient flow coefficient and thickness coefficient showed different linear variation patterns when the height of the ceiling structure was longer than 35 cm or shorter than 30 cm. Through numerical analysis, this study suggests that the main reason for the change in this linear pattern is whether the potential energy conversed from kinetic energy of the thin layer close to the ceiling structure can directly make the smoke to cross the ceiling structure. The research conclusions of this paper can assist in the engineering design of building smoke control and personnel evacuation.

10.
Circulation ; 150(13): 981-993, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39166327

RESUMEN

BACKGROUND: Colchicine has been approved to reduce cardiovascular risk in patients with coronary heart disease on the basis of its potential benefits demonstrated in the COLCOT (Colchicine Cardiovascular Outcomes Trial) and LoDoCo2 (Low-Dose Colchicine 2) studies. Nevertheless, there are limited data available about the specific impact of colchicine on coronary plaques. METHODS: This was a prospective, single-center, randomized, double-blind clinical trial. From May 3, 2021, until August 31, 2022, a total of 128 patients with acute coronary syndrome aged 18 to 80 years with lipid-rich plaque (lipid pool arc >90°) detected by optical coherence tomography were included. The subjects were randomly assigned in a 1:1 ratio to receive either colchicine (0.5 mg once daily) or placebo for 12 months. The primary end point was the change in the minimal fibrous cap thickness from baseline to the 12-month follow-up. RESULTS: Among 128 patients, 52 in the colchicine group and 52 in the placebo group completed the study. The mean age of the 128 patients was 58.0±9.8 years, and 25.0% were female. Compared with placebo, colchicine therapy significantly increased the minimal fibrous cap thickness (51.9 [95% CI, 32.8 to 71.0] µm versus 87.2 [95% CI, 69.9 to 104.5] µm; difference, 34.2 [95% CI, 9.7 to 58.6] µm; P=0.006), and reduced average lipid arc (-25.2° [95% CI, -30.6° to -19.9°] versus -35.7° [95% CI, -40.5° to -30.8°]; difference, -10.5° [95% CI, -17.7° to -3.4°]; P=0.004), mean angular extension of macrophages (-8.9° [95% CI, -13.3° to -4.6°] versus -14.0° [95% CI, -18.0° to -10.0°]; difference, -6.0° [95% CI, -11.8° to -0.2°]; P=0.044), high-sensitivity C-reactive protein level (geometric mean ratio, 0.6 [95% CI, 0.4 to 1.0] versus 0.3 [95% CI, 0.2 to 0.5]; difference, 0.5 [95% CI, 0.3 to 1.0]; P=0.046), interleukin-6 level (geometric mean ratio, 0.8 [95% CI, 0.6 to 1.1] versus 0.5 [95% CI, 0.4 to 0.7]; difference, 0.6 [95% CI, 0.4 to 0.9]; P=0.025), and myeloperoxidase level (geometric mean ratio, 1.0 [95% CI, 0.8 to 1.2] versus 0.8 [95% CI, 0.7 to 0.9]; difference, 0.8 [95% CI, 0.6 to 1.0]; P=0.047). CONCLUSIONS: Our findings suggested that colchicine resulted in favorable effects on coronary plaque stabilization at optical coherence tomography in patients with acute coronary syndrome. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04848857.


Asunto(s)
Síndrome Coronario Agudo , Colchicina , Placa Aterosclerótica , Tomografía de Coherencia Óptica , Humanos , Colchicina/uso terapéutico , Femenino , Síndrome Coronario Agudo/tratamiento farmacológico , Síndrome Coronario Agudo/diagnóstico por imagen , Persona de Mediana Edad , Masculino , Placa Aterosclerótica/tratamiento farmacológico , Placa Aterosclerótica/diagnóstico por imagen , Método Doble Ciego , Anciano , Estudios Prospectivos , Adulto , Resultado del Tratamiento , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Enfermedad de la Arteria Coronaria/diagnóstico por imagen
11.
STAR Protoc ; 5(3): 103182, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39093703

RESUMEN

S-acylation of proteins allows their association with membranes. Here, we present a protocol for establishing a platform for membrane affinity evaluation of S-acylated proteins in vitro. We describe steps for preparing lipid-maleimide compounds, mCherry-p62 recombinant proteins, and total cellular membranes. We then detail procedures for synthesizing protein-lipid conjugates using lipid-maleimide compounds and recombinant proteins and evaluating the membrane affinity of protein-lipid conjugates. For complete details on the use and execution of this protocol, please refer to Huang Xue et al.1.


Asunto(s)
Membrana Celular , Acilación , Membrana Celular/metabolismo , Membrana Celular/química , Lípidos/química , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Humanos , Maleimidas/química , Animales
13.
Adv Mater ; 36(41): e2406950, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39152933

RESUMEN

The performance of organic photodetectors (OPDs) sensitive to the short-wavelength infrared (SWIR) light lags behind commercial indium gallium arsenide (InGaAs) photodetectors primarily due to the scarcity of organic semiconductors with efficient photoelectric responses exceeding 1.3 µm. Limited by the Energy-gap law, ultralow-bandgap organic semiconductors usually suffer from severe non-radiative transitions, resulting in low external quantum efficiency (EQE). Herein, a difluoro-substituted quinoid terminal group (QC-2F) with exceptionally strong electron-negativity is developed for constructing a new non-fullerene acceptor (NFA), Y-QC4F with an ultralow bandgap of 0.83 eV. This subtle structural modification significantly enhances intermolecular packing order and density, enabling an absorption onset up to 1.5 µm while suppressing non-radiation recombination in Y-QC4F films. SWIR OPDs based on Y-QC4F achieve an impressive detectivity (D*) over 1011 Jones from 0.4 to 1.5 µm under 0 V bias, with a maximum of 1.68 × 1012 Jones at 1.16 µm. Furthermore, the resulting OPDs demonstrate competitive performance with commercial photodetectors for high-quality SWIR imaging even under 1.4 µm irradiation.

14.
World J Clin Cases ; 12(19): 3717-3724, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38994302

RESUMEN

BACKGROUND: The serratus anterior muscle, located in the lateral aspect of the thorax, plays a crucial role in shoulder movement and stability. Thoracoscopic surgery, while minimally invasive, often results in significant postoperative pain, complicating patient recovery and potentially extending hospital stays. Traditional anesthesia methods may not adequately address this pain, leading to increased complications such as agitation due to inadequate pain management. AIM: To evaluate the application value of ultrasound-guided serratus anterior plane block (SAPB) in patients undergoing thoracoscopic surgery, focusing on its effects on postoperative analgesia and rehabilitation. METHODS: Eighty patients undergoing thoracoscopic surgery between August 2021 and December 2022 were randomly divided into two groups: An observation group receiving ultrasound-guided SAPB and a control group receiving standard care without SAPB. Both groups underwent general anesthesia and were monitored for blood pressure, heart rate (HR), oxygen saturation, and pulse. The primary outcomes measured included mean arterial pressure (MAP), HR, postoperative visual analogue scale (VAS) scores for pain, supplemental analgesic use, and incidence of agitation. RESULTS: The observation group showed significantly lower cortisol and glucose concentrations at various time points post-operation compared to the control group, indicating reduced stress responses. Moreover, MAP and HR levels were lower in the observation group during and after surgery. VAS scores were significantly lower in the observation group at 1 h, 4 h, 6 h, and 12 h post-surgery, and the rates of analgesic supplementation and agitation were significantly reduced compared to the control group. CONCLUSION: Ultrasound-guided SAPB significantly improves postoperative analgesia and reduces agitation in patients undergoing thoracoscopic surgery. This technique stabilizes perioperative vital signs, decreases the need for supplemental analgesics, and minimizes postoperative pain and stress responses, underscoring its high application value in enhancing patient recovery and rehabilitation post-thoracoscopy.

15.
Materials (Basel) ; 17(13)2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38998455

RESUMEN

The study reports the significance of carbon presence in affecting void nucleation in Fe. Without carbon, void nucleation rates decrease gradually at high temperatures but remain significantly high and almost saturated at low temperatures. With carbon present, even at 1 atomic parts per million, void nucleation rates show a low-temperature cutoff. With higher carbon levels, the nucleation temperature window becomes narrower, the maximum nucleation rate becomes lower, and the temperature of maximum void nucleation shifts to a higher temperature. Fundamentally, this is caused by the change in effective vacancy diffusivity due to the formation of carbon-vacancy complexes. The high sensitivity of void nucleation to carbon comes from the high sensitivity of void nucleation to the vacancy arrival rate in a void. The void nucleation is calculated by first obtaining the effective vacancy diffusivity considering the carbon effect, then calculating the defect concentration and defect flux change considering both carbon effects and pre-existing dislocations, and finally calculating the void nucleation rate based on the recently corrected homogeneous void nucleation theory. The study is important not only in the fundamental understanding of impurity effects in ion/neutron irradiation but also in alloy engineering for judiciously introducing impurities to increase swelling resistance, as well as in the development of simulation and modeling methodologies applicable to other metals.

16.
New Phytol ; 243(6): 2401-2415, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39073209

RESUMEN

Mycorrhizal associations are key mutualisms that shape the structure of forest communities and multiple ecosystem functions. However, we lack a framework for predicting the varying dominance of distinct mycorrhizal associations in an integrated proxy of multifunctionality across ecosystems. Here, we used the datasets containing diversity of mycorrhizal associations and 18 ecosystem processes related to supporting, provisioning, and regulating services to examine how the dominance of ectomycorrhiza (EcM) associations affects ecosystem multifunctionality in subtropical mountain forests in Southwest China. Meanwhile, we synthesized the prevalence of EcM-dominant effects on ecosystem functioning in forest biomes. Our results demonstrated that elevation significantly modified the distributions of EcM trees and fungal dominance, which in turn influenced multiple functions simultaneously. Multifunctionality increased with increasing proportion of EcM associations, supporting the ectomycorrhizal-dominance hypothesis. Meanwhile, we observed that the impacts of EcM dominance on individual ecosystem functions exhibited different relationships among forest biomes. Our findings highlight the importance of ectomycorrhizal dominance in regulating multifunctionality in subtropical forests. However, this ectomycorrhizal feedback in shaping ecosystem functions cannot necessarily be generalized across forests. Therefore, we argue that the predictions for ecosystem multifunctionality in response to the shifts of mycorrhizal composition could vary across space and time.


Asunto(s)
Bosques , Micorrizas , Micorrizas/fisiología , Clima Tropical , China , Ecosistema , Modelos Biológicos , Árboles/microbiología , Árboles/fisiología , Biodiversidad , Altitud
17.
Molecules ; 29(13)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38998978

RESUMEN

The regulation of the cancer cell cycle heavily relies on cyclin-dependent kinases (CDKs). Targeting CDKs has been identified as a promising approach for effective cancer therapy. In recent years, there has been significant attention paid towards developing small-molecule CDK inhibitors in the field of drug discovery. Notably, five such inhibitors have already received regulatory approval for the treatment of different cancers, including breast tumors, lung malignancies, and hematological malignancies. This review provides an overview of the synthetic routes used to produce 17 representative small-molecule CDK inhibitors that have obtained regulatory approval or are currently being evaluated through clinical trials. It also discusses their clinical applications for treating CDK-related diseases and explores the challenges and limitations associated with their use in a clinical setting, which will stimulate the further development of novel CDK inhibitors. By integrating therapeutic applications, synthetic methodologies, and mechanisms of action observed in various clinical trials involving these CDK inhibitors, this review facilitates a comprehensive understanding of the versatile roles and therapeutic potential offered by interventions targeting CDKs.


Asunto(s)
Antineoplásicos , Quinasas Ciclina-Dependientes , Neoplasias , Inhibidores de Proteínas Quinasas , Bibliotecas de Moléculas Pequeñas , Humanos , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Quinasas Ciclina-Dependientes/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/síntesis química , Neoplasias/tratamiento farmacológico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antineoplásicos/química , Antineoplásicos/síntesis química , Bibliotecas de Moléculas Pequeñas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/uso terapéutico , Bibliotecas de Moléculas Pequeñas/síntesis química , Animales , Descubrimiento de Drogas , Ensayos Clínicos como Asunto
18.
Eur J Med Chem ; 275: 116610, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38896992

RESUMEN

Mutations in IDH1 are commonly observed across various cancers, causing the conversion of α-KG to 2-HG. Elevated levels of 2-HG disrupt histone and DNA demethylation processes, promoting tumor development. Consequently, there is substantial interest in developing small molecule inhibitors targeting the mutant enzymes. Herein, we report a structure-based high-throughput virtual screening strategy using a natural products library, followed by hit-to-lead optimization. Through this process, we discover a potent compound, named 11s, which exhibited significant inhibition to IDH1 R132H and IDH1 R132C with IC50 values of 124.4 and 95.7 nM, respectively. Furthermore, 11s effectively reduced 2-HG formation, with EC50 values of 182 nM in U87 R132H cell, and 84 nM in HT-1080 cell. In addition, 11s significantly reduced U87 R132H and HT-1080 cell proliferation with GC50 values of 3.48 and 1.38 µM, respectively. PK-PD experiments further confirmed that compound 11s significantly decreased 2-HG formation in an HT-1080 xenograft mouse model, resulting in notable suppression of tumor growth without apparent loss in body weight.


Asunto(s)
Antineoplásicos , Productos Biológicos , Proliferación Celular , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos , Isocitrato Deshidrogenasa , Humanos , Relación Estructura-Actividad , Isocitrato Deshidrogenasa/antagonistas & inhibidores , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Productos Biológicos/farmacología , Productos Biológicos/química , Productos Biológicos/síntesis química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/síntesis química , Animales , Proliferación Celular/efectos de los fármacos , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Estructura Molecular , Mutación , Línea Celular Tumoral , Evaluación Preclínica de Medicamentos , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/patología , Neoplasias Experimentales/metabolismo
19.
Quant Imaging Med Surg ; 14(6): 3789-3802, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38846281

RESUMEN

Background: The noninvasive prediction of sentinel lymph node (SLN) metastasis using quantitative magnetic resonance imaging (MRI), particularly with synthetic MRI (syMRI), is an emerging field. This study aimed to explore the potential added benefits of syMRI over conventional MRI and diffusion-weighted imaging (DWI) in predicting metastases in SLNs. Methods: This retrospective study consecutively enrolled 101 patients who were diagnosed with breast cancer (BC) and underwent SLN biopsy from December 2022 to October 2023 at the Affiliated Hospital of Jiangnan University. These patients underwent preoperative MRI including conventional MRI, DWI, and syMRI and were categorized into two groups according to the postoperative pathological results: those with and without metastatic SLNs. MRI morphological features, DWI, and syMRI-derived quantitative parameters of breast tumors were statistically compared between these two groups. Binary logistic regression was used to separately develop predictive models for determining the presence of SLN involvement, with variables that exhibited significant differences being incorporated. The performance of each model was evaluated through receiver operating characteristic (ROC) curve analysis, including the area under the curve (AUC), sensitivity, and specificity. Results: Compared to the group of 54 patients with BC but no metastatic SLNs, the group of 47 patients with BC and metastatic SLNs had a significantly larger maximum axis diameter [metastatic SLNs: median 2.40 cm, interquartile range (IQR) 1.50-3.00 cm; no metastatic SLNs: median 1.80 cm, IQR 1.37-2.50 cm; P=0.03], a higher proton density (PD) (78.44±11.92 vs. 69.20±10.63 pu; P<0.001), and a lower apparent diffusion coefficient (ADC) (metastatic SLNs: median 0.91×10-3 mm2/s, IQR 0.79-1.01 mm2/s; no metastatic SLNs: median 1.02×10-3 mm2/s, IQR 0.92-1.12 mm2/s; P=0.001). Moreover, the prediction model with maximum axis diameter and ADC yielded an AUC of 0.71 [95% confidence interval (CI): 0.618-0.802], with a sensitivity of 78.72% and a specificity of 51.85%; After addition of syMRI-derived PD to the prediction model, the AUC increased significantly to 0.86 (AUC: 0.86 vs. 0.71; 95% CI: 0.778-0.922; P=0.002), with a sensitivity of 80.85% and a specificity of 81.50%. Conclusions: Combined with conventional MRI and DWI, syMRI can offer additional value in enhancing the predictive performance of determining SLN status before surgery in patients with BC.

20.
iScience ; 27(6): 110006, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38868202

RESUMEN

Apolipoprotein E (apoE) plays a crucial role in the pathogenesis of Alzheimer's disease (AD). Microglia exhibit a substantial upregulation of apoE in AD-associated circumstances, despite astrocytes being the primary source of apoE expression and secretion in the brain. Although the role of astrocytic apoE in the brain has been extensively investigated, it remains unclear that whether and how apoE particles generated from astrocytes and microglia differ in biological characteristic and function. Here, we demonstrate the differences in size between apoE particles generated from microglia and astrocytes. Microglial apoE particles impair neurite growth and synapses, and promote neuronal senescence, whereas depletion of GPNMB (glycoprotein non-metastatic melanoma protein B) in microglial apoE particles mitigated these deleterious effects. In addition, human APOE4-expressing microglia are more neurotoxic than APOE3-bearing microglia. For the first time, these results offer concrete evidence that apoE particles produced by microglia are involved in neuronal senescence and toxicity.

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