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1.
Nano Lett ; 2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39401413

RESUMEN

Aqueous zinc-bromine redox systems possess multiple merits for scalable energy storage. Applying bromine complexing agents shows effectiveness in alleviating the key challenge of ubiquitous crossover of reactive liquid bromine species, while the underlying microscopic mechanism requires a deep understanding to engineer better complexing electrochemistry. Herein, taking a series of quaternary ammonium ionic liquids (methyl4NBr, ethyl4NBr, propyl4NBr, and butyl4NBr) as a redox mediator model, operando optical monitoring was used to visualize the dynamic electrochemical behaviors, unveiling the ionic liquid-mediated polybromide electrochemistry with a distinct chain length effect. A longer chain length possesses a stronger electrostatic interaction in the complexing product to effectively capture Br2. Operando results reveal the liquid nature of the reversibly electrogenerated polybromide microdroplets in the butyl4NBr-added redox system, which promoted the Br3-/Br- conversion kinetics and alleviated the self-discharge for improved battery performance. This work provides direct evidence and new insights into complexing electrochemistry for advancing Zn-Br2 batteries.

2.
Ying Yong Sheng Tai Xue Bao ; 35(8): 2035-2043, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39419788

RESUMEN

Accurately monitoring and evaluating changes in ecological environment quality under earthquake disturbances is of great significance for the restoration and protection of regional ecological environment. In view of the "8·8" earthquake in Jiuzhaigou County in 2017, we used high-precision remote sensing image to analyze the vege-tation damage caused by the earthquake, and calculated remote sensing ecological index (RSEI) for the pre-earthquake period, post-earthquake period and 3-year recovery period based on GEE platform to analyze the spatio-temporal variation of ecological environment in Jiuzhaigou County, Sichuan Province. Then, we used geodetector to reveal the influencing factors of spatio-temporal variations in ecological restoration. The results showed that the fractional vegetation cover of Jiuzhaigou County decreased from 0.71 before the earthquake to 0.69 after the earthquake. The area of higher coverage zone decreased by 310.78 km2, while the area of others increased. The mean RESI decreased from 0.50 in the pre-earthquake period to 0.42 in the post-earthquake period, and increased to 0.50 after the 3-year recovery period. The ecological environment quality in the three period was mainly at the good and ave-rage levels, and it was distributed in the central and southern mountains and the eastern river valley. Annual precipitation, elevation, wet and greenness were the main factors controlling ecological quality restoration in Jiuzhaigou County, and the increases in the interaction among these factors would affect the spatial variations of regional ecological environment quality restoration.


Asunto(s)
Terremotos , Ecosistema , Monitoreo del Ambiente , Tecnología de Sensores Remotos , Análisis Espacio-Temporal , China , Monitoreo del Ambiente/métodos , Conservación de los Recursos Naturales
3.
Sci Rep ; 14(1): 23739, 2024 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-39390238

RESUMEN

Male infertility is one of the most common reproductive dysfunctions. Despite oligospermia being a cause of infertility, few studies have been conducted on it. This study aimed to investigate differences in semen metabolic patterns in patients with oligospermia and to identify potential biomarkers associated with oligospermia. Semen samples from oligospermia patients (20 cases) and healthy controls (20 cases) were detected by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), and 72 and 89 metabolites were identified as potential markers in positive and negative ion modes, respectively. In addition, the results identified multiple metabolic pathways in patients with oligospermia, such as glycine serine and threonine metabolism, Synthesis and degradation of ketone bodies, Valine, leucine, and isoleucine degradation. These results described unique metabolic characteristics of semen in patients with oligospermia and provided novel insights into the mechanism of the semen disorder.


Asunto(s)
Metabolómica , Oligospermia , Semen , Espectrometría de Masas en Tándem , Humanos , Masculino , Oligospermia/metabolismo , Espectrometría de Masas en Tándem/métodos , Semen/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Adulto , Metabolómica/métodos , Biomarcadores/metabolismo , Metaboloma , Estudios de Casos y Controles
4.
Acc Chem Res ; 57(20): 2985-3006, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39356824

RESUMEN

ConspectusAlkenes and alkynes are fundamental building blocks in organic synthesis due to their commercial availability, bench-stability, and easy preparation. Selective functionalization of alkenes and alkynes is a crucial step for the synthesis of value-added compounds. Precise control over these reactions allows efficient construction of complex molecules with new functionalities. In recent decades, second- and third-row precious transition metal catalysts (palladium, platinum, rhodium, ruthenium) have been pivotal in the development of metal-catalyzed synthetic methodology. These metals exhibit excellent catalytic activity and selectivity, enabling efficient synthesis of functionalized organic molecules. However, recovery and reuse of precious metals have long been a challenge in this field. In recent years, exploration of earth-abundant metal-catalyzed organic reactions has interested both academic and industrial researchers. The development of such catalytic systems offers a promising approach to overcome the limitations of precious metal catalysts. For example, manganese is the third most naturally abundant transition metal with minimal toxicity and excellent biocompatibility. It exhibits good catalytic activity in several organic reactions, including C-H bond functionalization, selective reduction, and radical reactions. This Account outlines our recent progress in dinuclear manganese catalysis for selective functionalization of alkenes and alkynes. We have established the elementary manganese(I)-catalysis in transmetalation with R-B(OH)2. This finding has enabled us to apply the catalyst for the selective 1,2-difunctionalization of structurally diverse alkenes and alkynes. Mechanistic studies suggest a double manganese center synergistic activation model, as superior to Mn(CO)5Br in some cases. In addition, we have developed a ligand-tuned metalloradical strategy of dinuclear manganese catalysts (Mn2(CO)10), bridging the gap between the organometallics and radical chemistry, highlighting the unique radical functionalization of alkenes. Interestingly, using the same starting materials, different ligands can deliver completely different products. Meanwhile, a cooperative catalysis strategy involving manganese and other catalysts (e.g., cobalt, iminium) has also been developed and is briefly discussed. For manganese/iminium synergistic catalysis, a new mechanism for migratory insertion and demetalization-isomerization in synergistic HOMO-LUMO activation was disclosed. This strategy expands the application of low-valent manganese catalysts for enantioselective C-C bond-forming reactions. New reaction discovery is outpacing mechanism studies for dinuclear manganese catalysis, and future studies with time-resolved spectroscopy will improve understanding of the mechanism. Based on these intriguing findings, the precise functionalization of alkenes and alkynes by dinuclear manganese catalysts will expedite a novel activation model to enable late-stage functionalization of complex molecules.

5.
Adv Sci (Weinh) ; : e2410357, 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39413017

RESUMEN

Developing efficient photo-piezocatalytic systems to achieve the conversion of renewable energy to chemical energy emerges enormous potential. However, poor catalytic efficiency remains a significant obstacle to future practical applications. Herein, a series of unique Au@BaTiO3 (Au@BT) yolk-shell nanostructure photo-piezocatalyst is constructed with single Au nanoparticle (Au NP) embedded in different positions within ferroelectric BaTiO3 hollow nanosphere (BT-HNS). This special structure showcases excellent mechanical force sensitivity and provides ample plasmon-induced interfacial charge-transfer pathways. In addition, the powerful piezoelectric polarization electric field induced by the enhanced ferroelectric polarization electric field via corona poling treatment in BT-HNS further promotes charge separation, CO2 adsorption and key intermediate conversion. Notably, BT with single Au NP encapsulated into hollow nanosphere shell with reinforced polarization (Au@BT-1-P) shows synergistically improved photo-piezocatalytic CO2 reduction activity for producing CO with a high production rate of 31.29 µmol g-1 h-1 under visible light irradiation and ultrasonic vibration. This work highlights a generic tactic for optimized design of high-performance and multifunctional nanostructured photo-piezocatalyst. Meanwhile, these yolk-in-shell nanostructures with single Au nanoparticle as an ideal model may hold great promise to inspire in-depth exploration of carrier dynamics and mechanistic understanding of the catalytic reaction.

6.
Cancer Control ; 31: 10732748241272482, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39403995

RESUMEN

BACKGROUND: Sedated colonoscopy has been increasingly selected. However, the effect of sedated colonoscopy on polyp/adenoma detection rate (PDR/ADR) remains controversial among studies. METHODS: In this retrospective study, the medical records of 11 504 consecutive patients who underwent colonoscopy at our department from July 1, 2021 to December 31, 2022 were collected. Patients were divided into sedated and unsedated groups according to the use of intravenous sedation during colonoscopy. Overall PDR/ADR, right-side, transverse, and left-side colon PDR/ADR, and single and multiple PDR/ADR were calculated. By adjusting for age, gender, body mass index, inpatient, screening/surveillance, cecal intubation time, colonoscopy withdrawal time ≥6 min, and an endoscopist's experience ≥5 years, multivariate logistic regression analyses were performed to evaluate the association of sedated colonoscopy with overall PDR/ADR, right-side, transverse, and left-side colon PDR/ADR, and single and multiple PDR/ADR, where the absence of PDR/ADR was used as reference. Odds ratios (ORs) with their 95% confidence intervals (CIs) were calculated. RESULTS: Overall, 2275 patients were included, of whom 293 and 1982 underwent sedated and unsedated colonoscopy, respectively. Multivariate logistic regression analyses showed that sedated colonoscopy was independently associated with lower overall PDR/ADR (OR = 0.640, 95% CI = 0.460-0.889, P = 0.008), right-side colon PDR/ADR (OR = 0.591, 95% CI = 0.417-0.837, P = 0.003), single PDR/ADR (OR = 0.659, 95% CI = 0.436-0.996, P = 0.048), and multiple PDR/ADR (OR = 0.586, 95% CI = 0.402-0.855, P = 0.005), but not transverse or left-side colon PDR/ADR. CONCLUSION: Sedated colonoscopy may not be beneficial in terms of overall PDR/ADR, right-side colon PDR/ADR, and number of polyps/adenomas. Thus, it should be selectively recommended. Additionally, it should be necessary to explore how to improve the quality of sedated colonoscopy.


Asunto(s)
Adenoma , Pólipos del Colon , Colonoscopía , Humanos , Colonoscopía/métodos , Femenino , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Pólipos del Colon/diagnóstico , Adenoma/diagnóstico , Anciano , Sedación Consciente/métodos , Adulto
7.
Biomaterials ; 314: 122881, 2024 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-39454506

RESUMEN

Substrate anchorage is essential for cell migration, and actin polymerization at cell front and myosin contractility at cell rear are known to govern cell forward movement. Yet their differential driving strategies for neutrophil migration on distinct adhesiveness substrates and their contributions to the migration-induced trail formation remain unclear. Here we explore the morphological changes, migration dynamics, and trail formation of neutrophils on ICAM-1 and PLL substrates, with a focus on the relationships among adhesive forces, traction forces, and out-of-plane forces. Results indicate that, on ICAM-1, neutrophil migration and trail formation rely on the coordinated interactions of Arp2/3 and myosin, along with biochemical regulation (via Syk and calpain) of adhesion and de-adhesion. This pattern leads to traction forces being concentrated at relatively fewer adhesive sites, facilitating cell forward migration. On PLL, however, neutrophils primarily depend on Arp2/3-mediated actin polymerization, resulting in a broader distribution of traction forces and weaker adhesions, which allows for higher leading-edge migrating velocities. Elevated membrane tension and out-of-plane forces generated by bleb protrusions on PLL reduce the reliance on myosin-driven contraction at the trailing edge, enabling easier tail detachment through elastic recoil. This work highlights the differential impact of substrate adhesiveness on neutrophil migration and trail formation and dynamics, providing new insights into cell migration mechanisms and potential therapeutic targets for inflammatory and immune-related disorders.

8.
Angew Chem Int Ed Engl ; : e202416221, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39370777

RESUMEN

Chiral catalysts for asymmetric catalysis represent a crucial research focus in chemistry and materials science. However, a few cases about chiral-dependent photocatalysts primarily focus on plasmonic noble metals. Particularly, developing chiral nano-catalysts that can be driven by mechanical energy remains in the blank stage. Herein, organic polymer-based enantiomers, chiral polar polyimide (PI) microspheric nano-assembly are synthesized as novel bifunctional catalysts for asymmetric photocatalysis and piezocatalysis. The PI catalyst enantiomers present enantioselectivity towards left- and right-circularly polarized light, demonstrating chiral-dependent H2O2 photoproduction. Interestingly, enantioselectivity of the catalyst reverses under irradiation of different bands, presenting tunability in the interaction between chiral catalysts and circularly polarized light. For the first time, enantioselective piezocatalytic behavior is demonstrated by the chiral polar PI catalysts. They show remarkable chiral preference for asymmetric Diels-Alder reaction and enantioselective conversion of tyrosine substrates under ultrasonic vibration. The findings provide a new perspective into exploring metal-free chiral catalysts and their asymmetric catalysis applications across multiple energy forms.

9.
EMBO J ; 43(20): 4656-4667, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39251884

RESUMEN

The Cas3 nuclease is utilized by canonical type I CRISPR-Cas systems for processive target DNA degradation, while a newly identified type I-F CRISPR variant employs an HNH nuclease domain from the natural fusion Cas8-HNH protein for precise target cleavage both in vitro and in human cells. Here, we report multiple cryo-electron microscopy structures of the type I-F Cas8-HNH system at different functional states. The Cas8-HNH Cascade complex adopts an overall G-shaped architecture, with the HNH domain occupying the C-terminal helical bundle domain (HB) of the Cas8 protein in canonical type I systems. The Linker region connecting Cas8-NTD and HNH domains adopts a rigid conformation and interacts with the Cas7.6 subunit, enabling the HNH domain to be in a functional position. The full R-loop formation displaces the HNH domain away from the Cas6 subunit, thus activating the target DNA cleavage. Importantly, our results demonstrate that precise target cleavage is dictated by a C-terminal helix of the HNH domain. Together, our work not only delineates the structural basis for target recognition and activation of the type I-F Cas8-HNH system, but also guides further developments leveraging this system for precise DNA editing.


Asunto(s)
Sistemas CRISPR-Cas , Microscopía por Crioelectrón , Proteínas Asociadas a CRISPR/química , Proteínas Asociadas a CRISPR/metabolismo , Proteínas Asociadas a CRISPR/genética , Dominios Proteicos , Modelos Moleculares , Humanos , Conformación Proteica
10.
Nat Commun ; 15(1): 8408, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333121

RESUMEN

Glucagon-like peptide-1 (GLP-1) analogs are important therapeutics for type 2 diabetes and obesity. Ecnoglutide (XW003) is a novel, long-acting GLP-1 analog. We conducted a Phase 2, randomized, double-blind, placebo-controlled study enrolling 145 adults with T2DM. Participants were randomized to 0.4, 0.8, or 1.2 mg ecnoglutide or placebo as once-weekly injections for 20 weeks. The primary objective was to evaluate the efficacy of ecnoglutide, as measured by HbA1c change from baseline at Week 20. Secondary endpoints included body weight, glucose and lipid parameters, as well as safety. We show that, at end of treatment, the 0.4, 0.8, and 1.2 mg groups had statistically significant HbA1c reductions from baseline of -1.81%, -1.90%, and -2.39%, respectively, compared to -0.55% for placebo (P < 0.0001). At end of treatment, 71.9% of the 1.2 mg group had HbA1c ≤ 6.5% versus 9.1% on placebo, and 33.3% had body weight reductions ≥5% versus 3.0% for placebo. Ecnoglutide was generally safe and well tolerated. China Drug Trials Registry CTR20211014.


Asunto(s)
Diabetes Mellitus Tipo 2 , Péptido 1 Similar al Glucagón , Hemoglobina Glucada , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/sangre , Persona de Mediana Edad , Masculino , Femenino , Método Doble Ciego , Péptido 1 Similar al Glucagón/análogos & derivados , Péptido 1 Similar al Glucagón/uso terapéutico , Hemoglobina Glucada/metabolismo , Adulto , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Hipoglucemiantes/uso terapéutico , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/administración & dosificación , Anciano , Resultado del Tratamiento , Peso Corporal/efectos de los fármacos
11.
Front Public Health ; 12: 1442728, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39224554

RESUMEN

Background: China exited strict Zero-COVID policy with a surge in Omicron variant infections in December 2022. Given China's pandemic policy and population immunity, employing Baidu Index (BDI) to analyze the evolving disease landscape and estimate the nationwide pneumonia hospitalizations in the post Zero COVID period, validated by hospital data, holds informative potential for future outbreaks. Methods: Retrospective observational analyses were conducted at the conclusion of the Zero-COVID policy, integrating internet search data alongside offline records. Methodologies employed were multidimensional, encompassing lagged Spearman correlation analysis, growth rate assessments, independent sample T-tests, Granger causality examinations, and Bayesian structural time series (BSTS) models for comprehensive data scrutiny. Results: Various diseases exhibited a notable upsurge in the BDI after the policy change, consistent with the broader trajectory of the COVID-19 pandemic. Robust connections emerged between COVID-19 and diverse health conditions, predominantly impacting the respiratory, circulatory, ophthalmological, and neurological domains. Notably, 34 diseases displayed a relatively high correlation (r > 0.5) with COVID-19. Among these, 12 exhibited a growth rate exceeding 50% post-policy transition, with myocarditis escalating by 1,708% and pneumonia by 1,332%. In these 34 diseases, causal relationships have been confirmed for 23 of them, while 28 garnered validation from hospital-based evidence. Notably, 19 diseases obtained concurrent validation from both Granger causality and hospital-based data. Finally, the BSTS models approximated approximately 4,332,655 inpatients diagnosed with pneumonia nationwide during the 2 months subsequent to the policy relaxation. Conclusion: This investigation elucidated substantial associations between COVID-19 and respiratory, circulatory, ophthalmological, and neurological disorders. The outcomes from comprehensive multi-dimensional cross-over studies notably augmented the robustness of our comprehension of COVID-19's disease spectrum, advocating for the prospective utility of internet-derived data. Our research highlights the potential of Internet behavior in predicting pandemic-related syndromes, emphasizing its importance for public health strategies, resource allocation, and preparedness for future outbreaks.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiología , China/epidemiología , Estudios Retrospectivos , Hospitalización/estadística & datos numéricos , Teorema de Bayes , Política de Salud , Pandemias
12.
Adv Sci (Weinh) ; : e2405308, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39234812

RESUMEN

Incorporation of CO into substrates to construct high-value carbonyl compounds is an intensive industrial carbonylation procedure, however, high toxicity and wide explosion limits (12.5-74.0 vol% in air) of CO limit its application in industrial production. The development of a CO-free catalytic system for carbonylation is one of ideal methods, but full of challenge. Herein, this study reports the CO-free aminocarbonylation conversion of terminal alkynes synergistically catalyzed by a unique Co(ІІ)/Ag(І) metal-organic framework (MOF), in which the combination of isocyanides and O2 is employed as safe and green source of aminocarbonyl. This reaction has broad substrate applicability in terminal alkyne and isocyanides components with 100% atom economy. The bimetal MOF catalyst can be recycled at least five times without substantial loss of catalytic activities. Mechanistic investigations demonstrate that the synergistic effect between Ag(I) and Co(II) sites can efficiently activate terminal alkyne and isocyanides, respectively. Free radical capture experiments, FT-IR analysis and theoretical explorations further reveal that terminal alkynes and isocyanides can be catalytically transformed into an anionic intermediate through heterolysis pathways. This work provides secure and practical access to carbonylation as well as a new approach to aminocarbonylation of terminal alkynes.

13.
Comput Struct Biotechnol J ; 23: 3186-3198, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39263210

RESUMEN

Axolotls are known for their remarkable regeneration ability. Exploring their transcriptome provides insight into regenerative mechanisms. However, the current annotation of the axolotl transcriptome is limited, leaving the role of unannotated transcripts in regeneration unknown. To discourse this challenge, we exploited long-read sequencing technology, which enables direct observation of full-length RNA transcripts, greatly enhancing the coverage and accuracy of axolotl transcriptome annotation. By utilizing this method, we identified 222 novel gene loci and 4775 novel transcripts, which were quantified using short-read sequencing data. Through the inclusive analysis, we discovered novel homologs, potential functional proteins, noncoding RNAs, and alternative splicing events in key regeneration pathways. In particular, we identified novel transcripts with high protein-coding potential implicated in cell cycle regulation and musculoskeletal development, and regeneration were identified. Interestingly, alternative splice variants were also detected across diverse pathways critical to regeneration. This specifies that these novel transcripts potentially play vital roles underpinning the robust regenerative capacities of axolotls. Single-cell transcriptomic analysis further revealed these isoforms to predominantly exist in axolotl limb chondrocytes and mature tissue cell populations. Overall, the findings significantly advanced consideration of the axolotl transcriptome and provided a new perspective for understanding the mechanisms of regenerative abilities of axolotls.

14.
Heliyon ; 10(18): e37348, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39309940

RESUMEN

Background: Sorafenib is approved for the targeted therapy of cancers such as liver cancer and renal cancer. Given its widespread use, drug-related adverse events have received attention, and the post-marketing regulatory link is crucial. Objective: By using the FAERS database to mine the adverse events (AEs) related to sorafenib, comparing the association intensity of key AEs, and exploring potential drug-related AEs, it provides a reference for clinical medication. Methods: Collect ADE data related to sorafenib in the FAERS database from 2006 to 2023. Standardize the data, and map adverse events to system organ classes and preferred terms. Analyze using various signal quantification techniques such as ROR, PRR, BCPNN, and MGPS. Results: Among 18,520 adverse event reports (AERs) where sorafenib was the primary suspected drug, a total of 390 preferred terms (PTs) of adverse reactions were identified, covering 24 different system organ classes (SOCs). Specifically, the adverse events of sorafenib mainly involve the digestive system, skin and subcutaneous tissue, as well as non-specific physical discomfort including infection and injury. Among them, digestive system symptoms and skin toxicity are typical adverse reactions of sorafenib. We also observed uncommon but clearly strong AE signals, such as chloracne (n = 3, ROR 1756.39, PRR 1756.32, IC 8.78, EBGM 439.83), low-differentiated thyroid cancer (n = 4, ROR 585.47, PRR 585.44, IC 8.2, EBGM 293.22). It is worth noting that palmar-plantar erythrodysaesthesia syndrome (n = 2109, ROR 73.98, PRR 72.03, IC 6.01, EBGM 64.25) and hepatic encephalopathy (n = 457, ROR 37.44, PRR 37.23, IC 5.13, EBGM 35.07) have a higher incidence and signal intensity. In addition, we also observed some adverse events not mentioned in the official drug instructions, such as vitamin K deficiency or increased protein induced by antagonist II (PIVKA-II), abnormal alpha-fetoprotein, tumor metastasis, and splenic atrophy. Conclusion: Sorafenib carries the risk of various adverse reactions while providing therapeutic effects. In clinical applications, physicians should closely monitor the occurrence of digestive system reactions, skin lesions, endocrine system lesions, as well as injuries, infections, and other events.

15.
Angew Chem Int Ed Engl ; : e202416828, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39319629

RESUMEN

The combination of photothermal therapy (PTT) and photodynamic therapy (PDT) has become an attractive tumor treatment modality, yet the facile design of photoimmunotheranostic agents with efficient near infrared (NIR) light-absorbing and immune- activating capabilities remains a tremendous challenge. Herein, we developed a NIR-activable organic charge transfer complex (CTC), with perylene (PER) as the electron donor and 4,5,9,10-tetrabromoisochromeno [6,5,4-def]isochromene-1,3,6,8-tetraone (Br4NDI) as the electron acceptor. Through further supramolecular assembly, the PER-Br4NDI nanoparticle (PBND NP) for spatiotemporally controlled photoimmunotherapy was constructed. The PBND NP exhibits superb NIR absorption, robust intermolecular charge transfer, and enhanced intersystem crossing. Upon NIR photoirradiation, the PBND NP effectively exerts photothermal and photodynamic effects with a remarkable photothermal conversion efficiency of 63.5% and a high reactive oxygen species generation capability, which not only directly ablates primary tumors, but also dramatically suppresses distant tumor growth via promoted immunogenic cell death. Moreover, programmed cell death protein 1 antibody acts synergistically to block immune evasion and ultimately enhances cancer treatment efficacy. This work therefore sheds light on the design of organic CTCs for synergistic photoimmunotherapy.

16.
Diabetes Obes Metab ; 26(11): 5013-5024, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39308336

RESUMEN

AIM: We evaluated the efficacy and safety of cofrogliptin, a novel dipeptidyl peptidase-4 inhibitor taken once every 2 weeks (Q2W), compared with linagliptin (taken daily) in patients with type 2 diabetes inadequately controlled on metformin in China. MATERIALS AND METHODS: In this phase 3 randomized, double-blind, active-controlled, multicentre study, patients were randomly assigned 1:1:1 to receive cofrogliptin 10 mg Q2W, cofrogliptin 25 mg Q2W, or linagliptin 5 mg daily, all as an add-on treatment to metformin, for 24 weeks. Eligible patients could enter an open-label extension period and receive cofrogliptin 25 mg Q2W for an additional 28 weeks. The primary endpoint was change in glycated haemoglobin from baseline to 24 weeks, with a non-inferiority margin of 0.4% for cofrogliptin versus linagliptin treatment. RESULTS: Overall, 465 patients entered the 24-week treatment period (median age: 57.0 years). The least-squares mean (standard error) change in glycated haemoglobin from baseline to week 24 was -0.96 (0.063), -0.99 (0.064) and -1.07 (0.065) for the cofrogliptin 10 mg, cofrogliptin 25 mg and linagliptin 5 mg groups, respectively. The between-group difference met the predefined margin for non-inferiority of cofrogliptin (10 and 25 mg) versus linagliptin treatment. The incidence of common adverse events (≥5% patients) during the 24-week treatment period was similar between treatment groups. There were no serious hypoglycaemic events. CONCLUSION: In Chinese patients with type 2 diabetes inadequately controlled on metformin, the glucose-lowering effect of cofrogliptin (Q2W) was non-inferior to linagliptin (daily), with a similar safety profile maintained over 52 weeks of treatment.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Quimioterapia Combinada , Hemoglobina Glucada , Hipoglucemiantes , Linagliptina , Metformina , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/sangre , Linagliptina/uso terapéutico , Linagliptina/administración & dosificación , Metformina/uso terapéutico , Metformina/administración & dosificación , Persona de Mediana Edad , Método Doble Ciego , Masculino , Femenino , China/epidemiología , Hipoglucemiantes/uso terapéutico , Hipoglucemiantes/administración & dosificación , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Inhibidores de la Dipeptidil-Peptidasa IV/administración & dosificación , Anciano , Hemoglobina Glucada/análisis , Hemoglobina Glucada/efectos de los fármacos , Hemoglobina Glucada/metabolismo , Esquema de Medicación , Adulto , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Hipoglucemia/inducido químicamente , Hipoglucemia/epidemiología , Hipoglucemia/prevención & control , Resultado del Tratamiento
17.
Langmuir ; 40(36): 19125-19133, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39190551

RESUMEN

Chemodynamic therapy is an appealing modality in cancer treatment. However, its therapeutic effectiveness is impeded by insufficient catalytic efficiency and overexpression of glutathione (GSH) at the tumor site. In this study, a poly(o-phenylenediamine) (PoPD)@copper sulfide (CuS) nanoplatform was developed as dual-level reactive oxygen species (ROS) amplifier for enhanced photothermal-chemodynamic therapy. The PoPD@CuS nanoplatform exhibited photothermal performance, chemodynamic performance, and GSH-depleting capability. Alongside its improved photothermal conversion efficiency with tumor pH-responsiveness, the photothermal behavior of PoPD@CuS could elevate chemodynamic activity by regulating the temperature spatiotemporally, leading to increased ROS production. Moreover, GSH depletion of PoPD@CuS could suppress ROS scavenging, further enhancing oxidative stress in the tumor region. Consequently, functioning as a dual-level ROS amplifier, PoPD@CuS showcased remarkable effectiveness in photothermal-chemodynamic combination therapy.


Asunto(s)
Cobre , Especies Reactivas de Oxígeno , Especies Reactivas de Oxígeno/metabolismo , Cobre/química , Cobre/farmacología , Humanos , Animales , Fenilendiaminas/química , Fenilendiaminas/farmacología , Glutatión/metabolismo , Glutatión/química , Ratones , Terapia Fototérmica , Fototerapia/métodos , Línea Celular Tumoral , Antineoplásicos/química , Antineoplásicos/farmacología
18.
Chem Sci ; 15(31): 12511-12516, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39118628

RESUMEN

Selective activation of the benzylic C(sp3)-H bond is pivotal for the construction of complex organic frameworks. Achieving precise selectivity among C-H bonds with comparable energetic and steric profiles remains a profound synthetic challenge. Herein, we unveil a site- and stereoselective benzylic C(sp3)-H alkenylation utilizing metallaphotoredox catalysis. Various linear and cyclic (Z)-all-carbon tri- and tetrasubstituted olefins can be smoothly obtained. This strategy can be applied to complex substrates with multiple benzylic sites, previously deemed unsuitable due to the uncontrollable site-selectivity. In addition, sensitive functional groups such as terminal alkenyl and TMS groups are compatible under the mild conditions. The exceptional site-selectivity and broad substrate compatibility are attributed to the visible-light catalyzed relay electron transfer-proton transfer process. More importantly, we have extended this methodology to achieve enantioselective benzylic C(sp3)-H alkenylation, producing highly enantioenriched products. The applicability and scalability of our protocol are further validated through late-stage functionalization of complex structures and gram-scale operations, underscoring its practicality and robustness.

19.
Bone Res ; 12(1): 46, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39183236

RESUMEN

Osteogenesis imperfecta (OI) is a disorder of low bone mass and increased fracture risk due to a range of genetic variants that prominently include mutations in genes encoding type I collagen. While it is well known that OI reflects defects in the activity of bone-forming osteoblasts, it is currently unclear whether OI also reflects defects in the many other cell types comprising bone, including defects in skeletal vascular endothelium or the skeletal stem cell populations that give rise to osteoblasts and whether correcting these broader defects could have therapeutic utility. Here, we find that numbers of skeletal stem cells (SSCs) and skeletal arterial endothelial cells (AECs) are augmented in Col1a2oim/oim mice, a well-studied animal model of moderate to severe OI, suggesting that disruption of a vascular SSC niche is a feature of OI pathogenesis. Moreover, crossing Col1a2oim/oim mice to mice lacking a negative regulator of skeletal angiogenesis and bone formation, Schnurri 3 (SHN3), not only corrected the SSC and AEC phenotypes but moreover robustly corrected the bone mass and spontaneous fracture phenotypes. As this finding suggested a strong therapeutic utility of SHN3 inhibition for the treatment of OI, a bone-targeting AAV was used to mediate Shn3 knockdown, rescuing the Col1a2oim/oim phenotype and providing therapeutic proof-of-concept for targeting SHN3 for the treatment of OI. Overall, this work both provides proof-of-concept for inhibition of the SHN3 pathway and more broadly addressing defects in the stem/osteoprogenitor niche as is a strategy to treat OI.


Asunto(s)
Modelos Animales de Enfermedad , Osteogénesis Imperfecta , Nicho de Células Madre , Animales , Ratones , Huesos/patología , Huesos/efectos de los fármacos , Colágeno Tipo I/metabolismo , Colágeno Tipo I/genética , Ratones Endogámicos C57BL , Osteogénesis/efectos de los fármacos , Osteogénesis Imperfecta/patología , Osteogénesis Imperfecta/genética , Células Madre/metabolismo , Células Madre/patología , Masculino , Femenino
20.
Nano Lett ; 24(34): 10443-10450, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39140834

RESUMEN

Counterion adsorption at the solid-liquid interface affects numerous applications. However, the counterion adsorption density in the Stern layer has remained poorly evaluated. Here we report the direct determination of surface charge density at the shear plane between the Stern layer and the diffuse layer. By the Grahame equation extension and streaming current measurements for different solid surfaces in different aqueous electrolytes, we are able to obtain the counterion adsorption density in the Stern layer, which is mainly related to the surface charge density but is less affected by the bulk ion concentration. The charge inversion concentration is further found to be sensitive to the ion type and ion valence rather than to the charged surface, which is attributed to the ionic competitive adsorption and ion-ion correlations. Our findings offer a framework for understanding ion distribution in many physical and chemical processes where the Stern layer is ubiquitous.

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