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1.
Nature ; 610(7933): 661-666, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36198794

RESUMEN

Networks of optical clocks find applications in precise navigation1,2, in efforts to redefine the fundamental unit of the 'second'3-6 and in gravitational tests7. As the frequency instability for state-of-the-art optical clocks has reached the 10-19 level8,9, the vision of a global-scale optical network that achieves comparable performances requires the dissemination of time and frequency over a long-distance free-space link with a similar instability of 10-19. However, previous attempts at free-space dissemination of time and frequency at high precision did not extend beyond dozens of kilometres10,11. Here we report time-frequency dissemination with an offset of 6.3 × 10-20 ± 3.4 × 10-19 and an instability of less than 4 × 10-19 at 10,000 s through a free-space link of 113 km. Key technologies essential to this achievement include the deployment of high-power frequency combs, high-stability and high-efficiency optical transceiver systems and efficient linear optical sampling. We observe that the stability we have reached is retained for channel losses up to 89 dB. The technique we report can not only be directly used in ground-based applications, but could also lay the groundwork for future satellite time-frequency dissemination.

2.
Nature ; 589(7841): 214-219, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33408416

RESUMEN

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

3.
Nature ; 582(7813): 501-505, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32541968

RESUMEN

Quantum key distribution (QKD)1-3 is a theoretically secure way of sharing secret keys between remote users. It has been demonstrated in a laboratory over a coiled optical fibre up to 404 kilometres long4-7. In the field, point-to-point QKD has been achieved from a satellite to a ground station up to 1,200 kilometres away8-10. However, real-world QKD-based cryptography targets physically separated users on the Earth, for which the maximum distance has been about 100 kilometres11,12. The use of trusted relays can extend these distances from across a typical metropolitan area13-16 to intercity17 and even intercontinental distances18. However, relays pose security risks, which can be avoided by using entanglement-based QKD, which has inherent source-independent security19,20. Long-distance entanglement distribution can be realized using quantum repeaters21, but the related technology is still immature for practical implementations22. The obvious alternative for extending the range of quantum communication without compromising its security is satellite-based QKD, but so far satellite-based entanglement distribution has not been efficient23 enough to support QKD. Here we demonstrate entanglement-based QKD between two ground stations separated by 1,120 kilometres at a finite secret-key rate of 0.12 bits per second, without the need for trusted relays. Entangled photon pairs were distributed via two bidirectional downlinks from the Micius satellite to two ground observatories in Delingha and Nanshan in China. The development of a high-efficiency telescope and follow-up optics crucially improved the link efficiency. The generated keys are secure for realistic devices, because our ground receivers were carefully designed to guarantee fair sampling and immunity to all known side channels24,25. Our method not only increases the secure distance on the ground tenfold but also increases the practical security of QKD to an unprecedented level.

4.
Nucleic Acids Res ; 51(6): 2862-2876, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-36864669

RESUMEN

Understanding the assembly principles of biological macromolecular complexes remains a significant challenge, due to the complexity of the systems and the difficulties in developing experimental approaches. As a ribonucleoprotein complex, the ribosome serves as a model system for the profiling of macromolecular complex assembly. In this work, we report an ensemble of large ribosomal subunit intermediate structures that accumulate during synthesis in a near-physiological and co-transcriptional in vitro reconstitution system. Thirteen pre-50S intermediate maps covering the entire assembly process were resolved using cryo-EM single-particle analysis and heterogeneous subclassification. Segmentation of the set of density maps reveals that the 50S ribosome intermediates assemble based on fourteen cooperative assembly blocks, including the smallest assembly core reported to date, which is composed of a 600-nucleotide-long folded rRNA and three ribosomal proteins. The cooperative blocks assemble onto the assembly core following defined dependencies, revealing the parallel pathways at both early and late assembly stages of the 50S subunit.


Asunto(s)
ARN Ribosómico , Ribosomas , Ribosomas/genética , Ribosomas/metabolismo , ARN Ribosómico/metabolismo , Proteínas Ribosómicas/metabolismo , Subunidades Ribosómicas Grandes/metabolismo
5.
J Med Virol ; 96(4): e29549, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38563352

RESUMEN

Previous research has explored theories regarding the vertical transmission of human papillomavirus (HPV) infection and its association with adverse pregnancy and perinatal outcomes. However, the impact of maternal HPV infection on congenital anomalies (CAs) in offspring remains relatively understudied. We conducted a population-based cohort study linking the Taiwan Birth Registry, Taiwan Death Registry, and National Health Insurance Research Database, in which newborns born in Taiwan between 2009 and 2015 were included. We established a maternal HPV infection cohort comprising 37 807 newborns and matched them with a comparison group of 151 228 newborns at a 1:4 ratio based on index year, age, and sex. The study examined a composite outcome and subgroups of different types of congenital malformations. Differences in cumulative incidence of CAs were assessed using Kaplan-Meier curves and log-rank tests. Adjusted hazard ratios (aHRs) were estimated using Cox proportional hazard regressions. No significant association was found between HPV infection and the broad spectrum of CAs (aHR: 1.04, 95% confidence interval [CI]: 0.98-1.10; log-rank test p = 0.14). However, we observed a 19% increased risk of musculoskeletal CAs in the maternal HPV infection group (aHR: 1.19; 95% CI: 1.05-1.34) compared to those without maternal HPV exposure. Other factors, including the type of HPV (aHR: 0.65; 95% CI: 0.16-2.63), the timing of exposure (during or before pregnancy), and maternal age (aHR for <30 years: 1.02, 95% CI: 0.94-1.1; aHR for 30-39 years: 1.05, 95% CI: 0.99-1.11; aHR for ≥40 years: 0.88, 95% CI: 0.67-1.17), did not significantly affect the risk for any CA. In conclusion, gestation detection of HPV infection was associated with musculoskeletal CAs but not other major CAs. Prospective studies are warranted to elucidate the necessity of prenatal screening in populations at risk.


Asunto(s)
Infecciones por Papillomavirus , Embarazo , Femenino , Humanos , Recién Nacido , Adulto , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Estudios de Cohortes , Estudios Prospectivos , Investigación , Taiwán/epidemiología , Factores de Riesgo
6.
Opt Express ; 32(7): 12601-12608, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571078

RESUMEN

Silicon avalanche photodiode (APD) single-photon detectors in space are continuously affected by radiation, which gradually degrades their dark count performance. From August 2016 to June 2023, we conducted approximately seven years (2507 days) of in-orbit monitoring of the dark count performance of APD single-photon detectors on the Micius Quantum Science Experimental Satellite. The results showed that due to radiation effects, the dark count growth rate was approximately 6.79 cps/day @ -24 °C and 0.37 cps/day @ -55 °C, with a significant suppression effect on radiation-induced dark counts at lower operating temperature. Based on the proposed radiation damage induced dark count annealing model, simulations were conducted for the in-orbit dark counts of the detector, the simulation results are consistent with in-orbit test data. In May 2022, four of these detectors underwent a cumulative 5.7 hours high-temperature annealing test at 76 °C, dark count rate shows no measurable changes, consistent with annealing model. As of now, these ten APD single-photon detectors on the Micius Quantum Science Experimental Satellite have been in operation for approximately 2507 days and are still functioning properly, providing valuable experience for the future long-term space applications of silicon APD single-photon detectors.

7.
Opt Express ; 32(7): 12645-12655, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571082

RESUMEN

The space time frequency transfer plays a crucial role in applications such as space optical clock networks, navigation, satellite ranging, and space quantum communication. Here, we propose a high-precision space time frequency transfer and time synchronization scheme based on a simple intensity modulation/direct detection (IM/DD) laser communication system, which occupies a communication bandwidth of approximately 0.2%. Furthermore, utilizing an optical-frequency comb time frequency transfer system as an out-of-loop reference, experimental verification was conducted on a 113 km horizontal atmospheric link, with a long-term stability approximately 8.3 × 10-16 over a duration of 7800 seconds. Over an 11-hour period, the peak-to-peak wander is approximately 100 ps. Our work establishes the foundation of the time frequency transfer, based on the space laser communication channel, for future ground-to-space and inter-satellite links.

8.
Opt Express ; 32(3): 3989-3996, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297608

RESUMEN

With the rapid development of superconducting quantum computing and the implementation of surface code, large-scale quantum computing is emerging as an urgent demand. In a superconducting computing system, the qubit is maintained in a cryogenic environment to avoid thermal excitation. Thus, the transmission of control signals, which are generated at room temperature, is needed. Typically, the transmission of these signals to the qubit relies on a coaxial cable wiring approach. However, in a large-scale computing system with hundreds or even thousands of qubits, the coaxial cables will pose great space and heat load to the dilution refrigerator. Here, to tackle this problem, we propose and demonstrate a direct-modulation-based optical transmission line. In our experiment, the average single-qubit XEB error and control error are measured as 0.139% and 0.014% separately, demonstrating the feasibility of the optical wiring approach and paving the way for large-scale superconducting quantum computing.

9.
Cancer Cell Int ; 24(1): 63, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336727

RESUMEN

The incidence of melanoma, the most lethal form of skin cancer, has increased due to ultraviolet exposure. The treatment of advanced melanoma, particularly metastatic cases, remains challenging with poor outcomes. Targeted therapies involving BRAF/MEK inhibitors and immunotherapy based on anti-PD1/anti-CTLA4 antibodies have achieved long-term survival rates of approximately 50% for patients with advanced melanoma. However, therapy resistance and inadequate treatment response continue to hinder further breakthroughs in treatments that increase survival rates. This review provides an introduction to the molecular-level pathogenesis of melanoma and offers an overview of current treatment options and their limitations. Cells can die by either accidental or regulated cell death (RCD). RCD is an orderly cell death controlled by a variety of macromolecules to maintain the stability of the internal environment. Since the uncontrolled proliferation of tumor cells requires evasion of RCD programs, inducing the RCD of melanoma cells may be a treatment strategy. This review summarizes studies on various types of nonapoptotic RCDs, such as autophagy-dependent cell death, necroptosis, ferroptosis, pyroptosis, and the recently discovered cuproptosis, in the context of melanoma. The relationships between these RCDs and melanoma are examined, and the interplay between these RCDs and immunotherapy or targeted therapy in patients with melanoma is discussed. Given the findings demonstrating melanoma cell death in response to different stimuli associated with these RCDs, the induction of RCD shows promise as an integral component of treatment strategies for melanoma.

10.
Cell Commun Signal ; 22(1): 259, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38715050

RESUMEN

Ubiquitination and deubiquitination are important forms of posttranslational modification that govern protein homeostasis. Deubiquitinating enzymes (DUBs), a protein superfamily consisting of more than 100 members, deconjugate ubiquitin chains from client proteins to regulate cellular homeostasis. However, the dysregulation of DUBs is reportedly associated with several diseases, including cancer. The tumor microenvironment (TME) is a highly complex entity comprising diverse noncancerous cells (e.g., immune cells and stromal cells) and the extracellular matrix (ECM). Since TME heterogeneity is closely related to tumorigenesis and immune evasion, targeting TME components has recently been considered an attractive therapeutic strategy for restoring antitumor immunity. Emerging studies have revealed the involvement of DUBs in immune modulation within the TME, including the regulation of immune checkpoints and immunocyte infiltration and function, which renders DUBs promising for potent cancer immunotherapy. Nevertheless, the roles of DUBs in the crosstalk between tumors and their surrounding components have not been comprehensively reviewed. In this review, we discuss the involvement of DUBs in the dynamic interplay between tumors, immune cells, and stromal cells and illustrate how dysregulated DUBs facilitate immune evasion and promote tumor progression. We also summarize potential small molecules that target DUBs to alleviate immunosuppression and suppress tumorigenesis. Finally, we discuss the prospects and challenges regarding the targeting of DUBs in cancer immunotherapeutics and several urgent problems that warrant further investigation.


Asunto(s)
Enzimas Desubicuitinizantes , Microambiente Tumoral , Humanos , Enzimas Desubicuitinizantes/metabolismo , Evasión Inmune , Neoplasias/inmunología , Neoplasias/patología , Neoplasias/enzimología , Neoplasias/metabolismo , Escape del Tumor , Microambiente Tumoral/inmunología , Ubiquitinación
11.
Eur Radiol ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38834786

RESUMEN

OBJECTIVES: We aimed to develop and validate a radiomics nomogram based on dual-energy computed tomography (DECT) images and clinical features to classify the time since stroke (TSS), which could facilitate stroke decision-making. MATERIALS AND METHODS: This retrospective three-center study consecutively included 488 stroke patients who underwent DECT between August 2016 and August 2022. The eligible patients were divided into training, test, and validation cohorts according to the center. The patients were classified into two groups based on an estimated TSS threshold of ≤ 4.5 h. Virtual images optimized the visibility of early ischemic lesions with more CT attenuation. A total of 535 radiomics features were extracted from polyenergetic, iodine concentration, virtual monoenergetic, and non-contrast images reconstructed using DECT. Demographic factors were assessed to build a clinical model. A radiomics nomogram was a tool that the Rad score and clinical factors to classify the TSS using multivariate logistic regression analysis. Predictive performance was evaluated using receiver operating characteristic (ROC) analysis, and decision curve analysis (DCA) was used to compare the clinical utility and benefits of different models. RESULTS: Twelve features were used to build the radiomics model. The nomogram incorporating both clinical and radiomics features showed favorable predictive value for TSS. In the validation cohort, the nomogram showed a higher AUC than the radiomics-only and clinical-only models (AUC: 0.936 vs 0.905 vs 0.824). DCA demonstrated the clinical utility of the radiomics nomogram model. CONCLUSIONS: The DECT-based radiomics nomogram provides a promising approach to predicting the TSS of patients. CLINICAL RELEVANCE STATEMENT: The findings support the potential clinical use of DECT-based radiomics nomograms for predicting the TSS. KEY POINTS: Accurately determining the TSS onset is crucial in deciding a treatment approach. The radiomics-clinical nomogram showed the best performance for predicting the TSS. Using the developed model to identify patients at different times since stroke can facilitate individualized management.

12.
Inorg Chem ; 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38946199

RESUMEN

The functionalization of polyoxovanadate clusters is promising but of great challenge due to the versatile coordination geometry and oxidation state of vanadium. Here, two unprecedented silsesquioxane ligand-protected "fully reduced" polyoxovanadate clusters were fabricated via a facial solvothermal methodology. The initial mixture of the two polyoxovanadate clusters with different colors and morphologies (green plate V14 and blue block V6) was successfully separated as pure phases by meticulously controlling the assembly conditions. Therein, the V14 cluster is the highest-nuclearity V-silsesquioxane cluster to date. Moreover, the transformation from a dimeric silsesquioxane ligand-protected V14 cluster to a cyclic hexameric silsesquioxane ligand-protected V6 cluster was also achieved, and the possible mechanism termed "ligand-condensation-involved dissociation reassembly" was proposed to explain this intricate conversion process. In addition, the robust V6 cluster was served as a heterogeneous catalyst for the synthesis of important heterocyclic compounds, quinazolinones, starting from 2-aminobenzamide and aldehydes. The V6 cluster exhibits high activity and selectivity to access pure quinazolinones under mild conditions, where the high selectivity was attributed to the confinement effect of the macrocyclic silsesquioxane ligand constraining the molecular freedom of the reaction species. The stability and recyclability as well as the tolerance of a wide scope of aldehyde substrates endow the V6 cluster with a superior performance and appreciable potential in catalytic applications.

13.
Nanotechnology ; 35(12)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38061057

RESUMEN

In this article, a 0.7 nm thick monolayer MoS2nanosheet gate-all-around field effect transistors (NS-GAAFETs) with conformal high-κmetal gate deposition are demonstrated. The device with 40 nm channel length exhibits a high on-state current density of ~410µAµm-1with a large on/off ratio of 6 × 108at drain voltage = 1 V. The extracted contact resistance is 0.48 ± 0.1 kΩµm in monolayer MoS2NS-GAAFETs, thereby showing the channel-dominated performance with the channel length scaling from 80 to 40 nm. The successful demonstration of device performance in this work verifies the integration potential of transition metal dichalcogenides for future logic transistor applications.

14.
Environ Sci Technol ; 58(4): 1976-1985, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38232111

RESUMEN

Rice is a dominant source of inorganic arsenic (As) exposure for populations consuming rice as a staple food. Decreasing As accumulation in rice grain is important for improving food safety. Arsenite [As(III)], the main form of As in paddy soil porewater, is taken up inadvertently by OsLsi1 and OsLsi2, the two key transporters for silicon (Si) uptake in rice roots. Here, we investigated whether editing OsLsi1 or OsLsi2 can decrease As accumulation in rice grain without compromising grain yield. We used the CRISPR-Cas9 technology to edit the promoter region of OsLsi1 and the C-terminal coding sequence of OsLsi1 and OsLsi2, and we generated a total of 27 mutants. Uptake and accumulation of Si and As were evaluated in both short-term hydroponic experiments and in a paddy field. Deletion of 1.2-2 kb of the OsLsi1 promoter suppressed OsLsi1 expression in roots and Si uptake markedly and did not affect As(III) uptake or grain As concentration. Some of the OsLsi1 and OsLsi2 coding sequence mutants showed large decreases in the uptake of Si and As(III) as well as large decreases in Si accumulation in rice husks. However, only OsLsi2 mutants showed significant decreases (by up to 63%) in the grain total As concentration. Editing OsLsi2 mainly affected the accumulation of inorganic As in rice grain with little effect on the accumulation of dimethylarsenate (DMA). Grain yields of the OsLsi2 mutants were comparable to those of the wild type. Editing OsLsi2 provides a promising way to reduce As accumulation in rice grain without compromising the grain yield.


Asunto(s)
Arsénico , Oryza , Contaminantes del Suelo , Silicio/metabolismo , Oryza/genética , Proteínas de Transporte de Membrana , Transporte Biológico , Suelo
15.
Nucleic Acids Res ; 50(3): 1734-1752, 2022 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-35048990

RESUMEN

In mammalian cells, small non-coding RNAs (sncRNAs) negatively regulate gene expression in a pathway known as RNA interference (RNAi). RNAi can be categorized into post-transcriptional gene silencing (PTGS), which involves the cleavage of target messenger RNA (mRNA) or inhibition of translation in the cytoplasm, and transcriptional gene silencing (TGS), which is mediated by the establishment of repressive epigenetic marks at target loci. Transfer RNAs (tRNAs), which are essential for translation, can be processed into small ncRNAs, termed tRNA-derived small RNAs (tsRNAs). The biogenesis of tsRNAs and their role in gene expression regulation has not yet been fully understood. Here, we show that Dicer dependent tsRNAs promote gene silencing through a mechanism distinct from PTGS and TGS. tsRNAs can lead to downregulation of target genes by targeting introns via nascent RNA silencing (NRS) in nuclei. Furthermore, we show that Ago2 slicer activity is required for this mechanism. Synthetic tsRNAs can significantly reduce expression of a target gene at both RNA and protein levels. Target genes regulated by NRS are associated with various diseases, which further underpins its biological significance. Finally, we show that NRS is evolutionarily conserved and has the potential to be explored as a novel synthetic sRNA based therapeutic.


Asunto(s)
Interferencia de ARN , ARN Pequeño no Traducido , ARN de Transferencia , Animales , Regulación de la Expresión Génica , Mamíferos/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , ARN Pequeño no Traducido/genética , ARN de Transferencia/genética , ARN de Transferencia/metabolismo
16.
BMC Public Health ; 24(1): 1405, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802740

RESUMEN

BACKGROUND: In an effort to identify factors associated with frailty transitions that trigger a significant difference in preventing and postponing the progression of frailty, questions regarding the role of cognitive leisure activities on various aspects of older adults' health were raised. However, the relationship between cognitive leisure activities and frailty transitions has rarely been studied. METHODS: A total of 5367 older Chinese adults aged over 60 years from the China Health and Retirement Longitudinal Study (CHARLS) were selected as participants. The 2nd wave of the CHARLS in 2013 was selected as the baseline, and sociodemographic and health-related status baseline data were collected. The FRAIL Scale was used to measure frailty, while cognitive leisure activities were measured by the Cognitive Leisure Activity Index (CLAI) scores, which consisted of playing mahjong or cards, stock investment, and using the internet. After two years of follow-up, frailty transition from baseline was assessed at the 3rd wave of the CHARLS in 2015. Ordinal logistic regression analysis was used to examine the relationship between cognitive leisure activities and frailty transitions. RESULTS: During the two-year follow-up of 5367 participants, the prevalence of frailty that improved, remained the same and worsened was 17.8% (957/5367), 57.5% (3084/5367) and 24.7% (1326/5367), respectively. Among all participants, 79.7% (4276/5367), 19.6% (1054/5367), and 0.7% (37/5367) had CLAI scores of 0, 1, and 2 to 3, respectively. In the univariate analysis, there was a statistically significant association between a score of 2 to 3 on the Cognitive Leisure Activity Index and frailty transitions (odds ratio [OR] = 1.93, 95% CI 0.03 to 1.29, p = .04), while all other covariates were not significantly different across the three groups. After adjusting for covariates, participants with more cognitive leisure activities had a higher risk of frailty improvement than those without cognitive leisure activities (odds ratio [OR] = 1.99, 95% CI 1.05 to 3.76, p = .04). CONCLUSIONS: Cognitive leisure activities were positively associated with the risk of frailty improvement in older adults, mainly when participating in multiple such activities. Older adults may be encouraged to participate in a wide variety of cognitive leisure activities to promote healthy aging.


Asunto(s)
Cognición , Fragilidad , Actividades Recreativas , Humanos , Actividades Recreativas/psicología , China/epidemiología , Anciano , Estudios Longitudinales , Masculino , Femenino , Persona de Mediana Edad , Fragilidad/psicología , Fragilidad/epidemiología , Anciano de 80 o más Años , Anciano Frágil/psicología , Anciano Frágil/estadística & datos numéricos
17.
Chem Biodivers ; : e202400719, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958461

RESUMEN

A versatile and efficient chemo selective synthesis of 4-aryl-3-formyl-2H-chromenes (AFC) was undertaken using Pd-catalyzed cross-coupling conditions. The key oxidative transmetalation was successfully applied to a significant range of substitutions on the chromene moiety and aryl ring in Ar(BOH)3, accommodating both electron-rich and electron-deficient groups. These π-extended scaffolds exhibited green-yellow fluorescence with a large Stokes shift and high quantum yield. Measurement of photophysical properties revealed that the compound with methoxy substitution in the chromene ring, 3t, caused a significant bathochromic shift. The AFCs obtained from this method can be transformed into biologically active 4-aryl-3-iminoantipyrine-2H-chromenes (AAC) through functionalization of the formyl chromenes. The AFCs and AACs with methoxy substitutions (3t and 4e) were docked against AChE inhibition, and compound 4e had the lowest binding energy of -11.20 kcal/mol. DFT calculations performed on representative compounds revealed that compound 4e is more reactive than 3t, which is in accordance with the docking studies.

18.
J Formos Med Assoc ; 123(2): 198-207, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37563020

RESUMEN

BACKGROUND: Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are used as the standard first-line treatment for patients with advanced EGFR-mutated non-small cell lung cancer (NSCLC). However, the impact of comorbidities and treatment toxicities on quality of life (QoL) was seldom investigated. OBJECTIVE: We aimed to investigate the association of comorbidities, adverse events (AEs), and QoL in treatment-naïve advanced NSCLC patients receiving EGFR-TKI treatments. METHODS: This multi-center prospective observational study was conducted to evaluate QoL and AEs at baseline, the 2nd, 4th, 12th, and 24th week. Clinical characteristics, comorbidities, and pre-treatment laboratory data were recorded. QoL was assessed by using the summary score of the EORTC QLQ-C30 and the dermatology life quality index. The impact of comorbidities, neutrophil-to-lymphocyte ratio (NLR), and AEs on QoL was analyzed by generalized estimating equations. RESULTS: A total of 121 patients were enrolled. Diarrhea (p = 0.033), anorexia (p < 0.001), and NLR ≥4 (p = 0.017) were significantly associated with a QoL impairment. Among skin toxicities, acneiform rash (p = 0.002), pruritus (p = 0.002), visual analogue scale for pruritus (≥3 and < 7, p = 0.006; ≥7, p = 0.001) and pain (1-3, p = 0.041) were associated with a QoL impairment. No significant association was found between comorbidities and QoL changes. CONCLUSION: Diarrhea, anorexia, skin pain, and pruritus may cause a deterioration in QoL in patients receiving EGFR-TKI therapy. NLR may be a potential predictive factor for QoL impairment. Aggressive management and close monitoring for these clinical factors are crucial to improve QoL.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Calidad de Vida , Anorexia , Neutrófilos , Dolor , Prurito , Diarrea , Linfocitos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Receptores ErbB/genética
19.
Nano Lett ; 23(7): 2710-2718, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36926943

RESUMEN

One scalable and facile dip-coating approach was utilized to construct a thin CO2-selection layer of Pebax/PEGDA-MXene on a hollow fiber PVDF substrate. An interlayer spacing of 3.59 Å was rationally designed and precisely controlled for the MXene stacks in the coated layer, allowing efficient separation of the CO2 (3.3 Å) from N2 (3.6 Å) and CH4 (3.8 Å). In addition, CO2-philic nanodomains in the separation layer were constructed by grafting PEGDA into MXene interlayers, which enhanced the CO2 affinity through the MXene interlayers, while non-CO2-philic nanodomains could promote CO2 transport due to the low resistance. The membrane could exhibit optimal separation performance with a CO2 permeance of 765.5 GPU, a CO2/N2 selectivity of 54.5, and a CO2/CH4 selectivity of 66.2, overcoming the 2008 Robeson upper bounds limitation. Overall, this facile approach endows a precise controlled molecular sieving MXene membrane for superior CO2 separation, which could be applied for interlayer spacing control of other 2D materials during membrane construction.

20.
Int J Mol Sci ; 25(5)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38473983

RESUMEN

Asians have a higher carrier rate of pulmonary arterial hypertension (PAH)-related genetic variants than Caucasians do. This study aimed to identify PAH-related genetic variants using whole exome sequencing (WES) in Asian idiopathic and heritable PAH cohorts. A WES library was constructed, and candidate variants were further validated by polymerase chain reaction and Sanger sequencing in the PAH cohort. In a total of 69 patients, the highest incidence of variants was found in the BMPR2, ATP13A3, and GDF2 genes. Regarding the BMPR2 gene variants, there were two nonsense variants (c.994C>T, p. Arg332*; c.1750C>T, p. Arg584*), one missense variant (c.1478C>T, p. Thr493Ile), and one novel in-frame deletion variant (c.877_888del, p. Leu293_Ser296del). Regarding the GDF2 variants, there was one likely pathogenic nonsense variant (c.259C>T, p. Gln87*) and two missense variants (c.1207G>A, p. Val403Ile; c.38T>C, p. Leu13Pro). The BMPR2 and GDF2 variant subgroups had worse hemodynamics. Moreover, the GDF2 variant patients were younger and had a significantly lower GDF2 value (135.6 ± 36.2 pg/mL, p = 0.002) in comparison to the value in the non-BMPR2/non-GDF2 mutant group (267.8 ± 185.8 pg/mL). The BMPR2 variant carriers had worse hemodynamics compared to the patients with the non-BMPR2/non-GDF2 mutant group. Moreover, there was a significantly lower GDF2 value in the GDF2 variant carriers compared to the control group. GDF2 may be a protective or corrected modifier in certain genetic backgrounds.


Asunto(s)
Hipertensión Arterial Pulmonar , Humanos , Hipertensión Arterial Pulmonar/genética , Hipertensión Pulmonar Primaria Familiar/genética , Mutación Missense , Hemodinámica , Eliminación de Secuencia , Receptores de Proteínas Morfogenéticas Óseas de Tipo II/genética , Mutación , Adenosina Trifosfatasas/genética , Proteínas de Transporte de Membrana/genética , Factor 2 de Diferenciación de Crecimiento/genética
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