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1.
J Immunol ; 211(9): 1287-1297, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37702994

RESUMEN

Staphylococcus aureus enterotoxin B (SEB), one of the most common bacterial toxins in food contamination, has been poorly understood in relationship to food allergy outcomes. To investigate whether the ingestion of enterotoxins in food allergens could affect the development of food allergy, OVA-sensitized female BALB/c mice were challenged with OVA added with different doses of SEB or LPS. Allergic symptoms, such as diarrhea rate and hypothermia, could be aggravated in mice challenged with OVA and a low dose of SEB. The increased differentiation of Th2 and reduced expression of CD103 in dendritic cells was found in mice coexposed to SEB and OVA. Additionally, there was an increasing differentiation of Th1 induced by a high dose of SEB. The expression of ST2+ in intestinal mast cells was also increased in mice sensitized with a low dose of SEB and OVA. Employing several in vitro cell culture models showed that the secretion of IL-33 from intestinal epithelial cells and IL-4 from group 2 innate lymphoid cells, activation of bone marrow-derived dendritic cells, and differentiation of naive T cells were induced by SEB and OVA. Our work proved that challenge with low-dose SEB and OVA partly aggravated the food allergy, suggesting a (to our knowledge) new finding of the potential cofactor of food allergy and that the contamination of SEB in food allergens deserves attention for allergic and normal individuals.

2.
Anal Chem ; 96(35): 14125-14132, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-38978161

RESUMEN

Mitochondrial DNA (mtDNA) is a unique genetic material characterized by maternal inheritance. It possesses a circular structure devoid of histone protection and exhibits low cellular abundance, which poses great challenges for its sensitive and selective detection at the living cell level. Herein, we have designed three bis-naphthylimide probes with varying linker lengths (NANn-OH, n = 0, 2, 6), facilitating the formation of distinct twisted or folded molecular conformations in the free state. These probes emit the red fluorescence around 627 nm with different fluorescence quantum yields (ΦNAN0-OH = 0.0016, ΦNAN2-OH = 0.0136, and ΦNAN6-OH = 0.0125). When encountering mtDNA (0.4-3.4 µg/mL), these probes undergo conformational changes depending on the length of the attached C-strand and exhibit a gradually increasing fluorescence signal around 453 nm. The fluorescence intensity increased to 13.5-fold, 1.9-fold, and 8.2-fold, respectively. Notably, the red fluorescence intensities around 627 nm remain constant throughout this process, thus serving as an inherent correction mechanism for proportional fluorescence signal enhancement to improve selectivity and sensitivity. NAN0-OH, NAN2-OH, and NAN6-OH showed good linearity for mtDNA in the range of 0.4-3.4 µg/mL with detection limits of LODNAN0-OH = 1.04 µg/mL, LODNAN2-OH = 1.10 µg/mL, and LODNAN6-OH = 1.15 µg/mL. Cellular experiments reveal that NAN6-OH effectively monitors curcumin-induced mtDNA damage in HepG-2 cells while enabling monitoring of genetic mtDNA damage. We anticipate that this tool holds significant potential for the precise evaluation of maternal genetic defects, thereby enhancing hypersensitive assessment in clinical medicine.


Asunto(s)
ADN Mitocondrial , Colorantes Fluorescentes , Espectrometría de Fluorescencia , Humanos , ADN Mitocondrial/genética , Colorantes Fluorescentes/química , Fluorescencia , Límite de Detección , Naftalimidas/química
3.
Immunol Cell Biol ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39044372

RESUMEN

Therapy-induced senescence can regulate both the innate and adaptive immune systems, thereby affecting therapeutic efficacy. Bleomycin is a major component of combined chemotherapy regimens, utilized for the treatment of multiple tumors, whereas pulmonary toxicity severely restricts its clinical benefits. As a member of the bleomycin family, boningmycin (BON) exhibits potent anticancer activity with minimal pulmonary toxicity, making it a potential alternative to bleomycin. Low concentrations of BON can induce senescence, but the impact of BON-induced senescence on anticancer immunity remains unclear. This study investigates the effects of BON-induced senescence on PD-L1 expression and the underlying mechanisms in human cancer cells. Firstly, the elevation of PD-L1 protein during BON-induced senescence was confirmed by a senescence ß-galactosidase staining assay, detection of the senescence-associated secretory phenotype (SASP), western blot and flow cytometry in human lung cancer NCI-H460 cells and breast cancer MDA-MB-231 cells. Subsequently, it was shown that the increase in PD-L1 protein is mediated by SASP, as evidenced by the use of conditional media, knockdown of cyclic GMP-AMP synthase and inhibition of stimulator of interferon genes. Ultimately, it was demonstrated that SASP-mediated PD-L1 up-regulation is dependent on the activation of the JAK/STAT pathway through the use of specific inhibitors and siRNAs. These findings clarify the impact of BON-induced senescence on PD-L1 expression and may contribute to the optimization of the therapeutic efficacy of bleomycin-related compounds and the clinical transformation of BON.

4.
Small ; 20(28): e2309263, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38321840

RESUMEN

The development of high-precision insoluble conducting polymer patterns for soft electronics is extremely challenging, mainly because of the incompatibility of the synthesis process with the underlying layers. In this study, a novel transfer-printing method is designed that enables the fabrication of photolithographic insoluble conducting polypyrrole (PPy) electrode patterns on soft substrates with high precision, demonstrating compatibility with various soft organic functional layers. Excellent mechanical stability, good biocompatibility, ultra-smooth surface, and outstanding conformability are observed. The photolithographic PPy electrode patterns, combined with an elastic organic semiconductor and dielectric, produce conformal all-organic transistors with mobility of 1.8 cm2 V-1 s-1. This study paves the way to use insoluble conducting polymers to develop complex, high-density flexible patterns and offers a promising organic electrode for the new-generation soft all-organic electronics.

5.
Small ; 20(29): e2311527, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38334257

RESUMEN

Stretchable organic transistors for skin-like biomedical applications require low-voltage operation to accommodate limited power supply and safe concerns. However, most of the currently reported stretchable organic transistors operate at relatively high voltages. Decreasing their operational voltage while keeping the high mobility still remains a key challenge. Here, the study presents a new dielectric design to achieve high-dielectric constant poly(urea-urethane) (PUU) elastomer, by incorporating a flexible small-molecular diamine crosslinking agent 4-aminophenyl disulfide (APDS) into the main chain of (poly (propylene glycol), tolylene 2,4-diiso-cyanate terminated) (PPG-TDI). Compared with commercial elastomers, the PUU elastomer as dielectric of the stretchable organic transistors shows the outstanding advantages including lower surface roughness (0.33 nm), higher adhesion (45.18 nN), higher dielectric constant (13.5), as well as higher stretchability (896%). The PUU dielectric enables the intrinsically stretchable, all-solution-processed organic transistor to operate at a low operational voltage down to -10 V, while preserving a substantial mobility of 1.39 cm2 V-1 s-1. Impressively, the transistor also demonstrates excellent electrical stability under repeated switching of 10 000 cycles, and remarkable mechanical robustness when stretched up to 100%. The work opens up a new molecular engineering strategy to successfully realize low-voltage high-mobility stretchable all-solution-processed organic transistors.

6.
J Org Chem ; 89(12): 8691-8705, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38856011

RESUMEN

Organocatalyzed diastereo- and enantioselective [3 + 2] cycloaddition reactions of donor-acceptor (D-A) cyclopropanes with isatin-derived ketimines are presented. Different from well-developed Lewis acid activation protocols which promote the reactivity of D-A cyclopropanes through coordinating to the acceptor group, in this reaction, dicyanocyclopropylmethyl ketones can be activated through nucleophilic activation of the donor group by using dihydroquinine-derived squaramide as Brønsted base catalyst. The reaction affords functionalized spiro[oxindole-3,2'-pyrrolidines] with two nonadjacent tetra- and tri-substituted stereocenters in 83-99% yields, moderate to excellent diastereoselectivities (up to >20:1 diastereomeric ratio (dr)), and excellent enantioselectivities (up to >99% enantiomeric excess (ee)) under mild conditions.

7.
Environ Sci Technol ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39109992

RESUMEN

The massive production and application of nanomaterials (NMs) have raised concerns about the potential adverse effects of NMs on human health and the environment. Evaluating the adverse effects of NMs by laboratory methods is expensive, time-consuming, and often fails to keep pace with the invention of new materials. Therefore, in silico methods that utilize machine learning techniques to predict the toxicity potentials of NMs are a promising alternative approach if regulatory confidence in them can be enhanced. Previous reviews and regulatory OECD guidance documents have discussed in detail how to build an in silico predictive model for NMs. Nevertheless, there is still room for improvement in addressing the ways to enhance the model representativeness and performance from different angles, such as data set curation, descriptor selection, task type (classification/regression), algorithm choice, and model evaluation (internal and external validation, applicability domain, and mechanistic interpretation, which is key to ensuring stakeholder confidence). This review explores how to build better predictive models; the current state of the art is analyzed via a statistical evaluation of literature, while the challenges faced and future perspectives are summarized. Moreover, a recommended workflow and best practices are provided to help in developing more predictive, reliable, and interpretable models that can assist risk assessment as well as safe-by-design development of NMs.

8.
BMC Anesthesiol ; 24(1): 155, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654209

RESUMEN

BACKGROUND: This study aimed to determine the median effective dose (ED50) and 95% effective dose (ED95) of nicardipine for treating pituitrin-induced hypertension during laparoscopic myomectomy, providing guidance for the management of intraoperative blood pressure in such patients. METHODS: Among the initial 40 participants assessed, 24 underwent elective laparoscopic myomectomy. A sequential up-and-down method was employed to ascertain the ED50 of nicardipine based on its antihypertensive efficacy. Nicardipine was initially administered at 6 µg/kg following the diagnosis of pituitrin-induced hypertension in the first patient. Dosing adjustments were made to achieve the desired antihypertensive effect, restoring systolic blood pressure and heart rate to within ± 20% of baseline within 120 s. The dosing increment or reduction was set at 0.5 µg/kg for effective or ineffective responses, respectively. The ED50 and ED95 of nicardipine were calculated using Probit regression by Maximum Likelihood Estimation (MLE) to establish dose-response curves and confidence intervals. RESULTS: 24 patients were included for analysis finally. The ED50 and ED95 of nicardipine for blood pressure control after pituitrin injection were determined. The study found that the ED50 of nicardipine for treating pituitrin-induced hypertension was 4.839 µg/kg (95% CI: 4.569-5.099 µg/kg), and the ED95 was estimated at 5.308 µg/kg (95% CI: 5.065-6.496 µg/kg). Nicardipine effectively mitigated the hypertensive response caused by pituitrin without inducing significant tachycardia or hypotension. CONCLUSIONS: Nicardipine effectively controlled blood pressure after pituitrin injection during laparoscopic myomectomy, with ED50 and ED95 values established. This research highlights the potential utility of nicardipine in addressing hypertensive responses induced by pituitrin, particularly in clinical settings where pituitrin is routinely administered.


Asunto(s)
Antihipertensivos , Relación Dosis-Respuesta a Droga , Hipertensión , Laparoscopía , Nicardipino , Miomectomía Uterina , Humanos , Nicardipino/administración & dosificación , Femenino , Adulto , Hipertensión/tratamiento farmacológico , Laparoscopía/métodos , Miomectomía Uterina/métodos , Antihipertensivos/administración & dosificación , Anestesia Intravenosa/métodos , Hormona Liberadora de Gonadotropina , Presión Sanguínea/efectos de los fármacos
9.
Ren Fail ; 46(2): 2398189, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39229915

RESUMEN

INTRODUCTION: Advanced chronic kidney disease (CKD) is common among patients with coronary artery disease (CAD), and angiotensin­converting enzyme inhibitors (ACEI) or angiotensin­receptor blockers (ARB) can improve cardiac and renal function, but whether ACEI/ARB therapy improves long-term prognosis remains unclear among these high-risk patients. Therefore, this research aimed to investigate the relationship between ACEI/ARB therapy and long-term prognosis among CAD patients with advanced CKD. METHODS: CAD patients with advanced CKD were included in five hospitals. Advanced CKD was defined as estimated glomerular filtration rate (eGFR)<30 ml/min per 1.73 m2. Cox regression models and competing risk Fine and Gray models were used to examine the relationship between ACEI/ARB therapy and all-cause and cardiovascular death, respectively. RESULTS: Of 2527 patients, 47.6% population of our cohort was discharged on ACEI/ARB. The overall all-cause and cardiovascular mortality were 38.6% and 24.7%, respectively. Multivariate Cox regression analyses indicated that ACEI/ARB therapy was found to be associated with lower rates of both all-cause mortality (hazard ratio (HR)=0.836, 95% confidence interval (CI): 0.738-0.948, p = 0.005) and cardiovascular mortality (HR = 0.817, 95%CI: 0.699-0.956, p = 0.011). In the propensity-matched cohort, the survival benefit was consistent, and significantly better survival was observed for all-cause mortality (HR = 0.856, 95%CI: 0.752-0.974, p = 0.019) and cardiovascular mortality (HR = 0.830, 95%CI: 0.707-0.974, p = 0.023) among patients treated with ACEI/ARB. CONCLUSION: ACEI/ARB therapy showed a better survival benefit among high-risk CAD patients with advanced CKD at long-term follow-up, which manifested that strategies to maintain ACEI/ARB treatment may improve clinical outcomes among these high-risk populations.


What is the current knowledge on the topic? Advanced CKD is highly prevalent and strongly associated with higher mortality risk and worse outcomes among CAD patients, and patients with advanced CKD have often been excluded from randomized controlled trials, creating an evidence gap for these high-risk CAD patients. ACEI/ARB are beneficial for greater survival among CAD patients, but the effect of ACEI/ARB therapy on long-term prognosis is unclear among CAD patients with advanced CKD.What does this study add to our knowledge? ACEI/ARB treatment showed a better survival benefit among high-risk CAD patients with advanced CKD at long-term follow-up.How might this change clinical pharmacology or translational science? CAD patients with advanced CKD are not only have worse outcomes but also limited in their choice of therapy strategies. Our study may prompt an important reference for the subsequent improvement of long-term prognosis among these high-risk populations.


Asunto(s)
Antagonistas de Receptores de Angiotensina , Inhibidores de la Enzima Convertidora de Angiotensina , Enfermedad de la Arteria Coronaria , Tasa de Filtración Glomerular , Insuficiencia Renal Crónica , Humanos , Masculino , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Femenino , Antagonistas de Receptores de Angiotensina/uso terapéutico , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/mortalidad , Persona de Mediana Edad , Anciano , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/mortalidad , Estudios Longitudinales , Modelos de Riesgos Proporcionales , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Causas de Muerte
10.
J Environ Manage ; 357: 120647, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38583385

RESUMEN

Subsidy policies are instrumental in driving the development of new energy. However, the effective allocation of new energy subsidies over time is challenging given fiscal constraints. This study addresses this challenge by considering the learning effect associated with the new energy industry. A two-stage dynamic programming model is proposed to capture the investment decision-making process of companies under new energy subsidy policies and government subsidy setups. Theoretical findings suggest that company investment decisions in new energy are influenced by a guiding principle: The subsidy rate should be negatively correlated with the variation rate of production scale increment (VRPSI). We calibrate this investment decision principle using wind power data from 14 countries. According to this principle, excessive subsidy rates may result in a low VRPSI, thereby diminishing future investment profitability in the new energy industry and leading to subsidy inefficiency. Upon investigating the efficiency of annual subsidy allocation, we find that the subsidy rates were potentially set too high in 2014, 2016, and 2017. Furthermore, the government should exercise caution regarding an inefficient subsidy pattern whereby companies invest in new energy only when the subsidy rate exceeds a certain threshold, neglecting traditional power sources. It is crucial to note that although this study uses wind power industry data for calibration and simulation, the theoretical model can be broadly applied to other new energy industries and emerging industries with increasing marginal net profit.


Asunto(s)
Industrias , Viento , Política Pública , Modelos Teóricos , Inversiones en Salud
11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(4): 404-410, 2024 Apr 10.
Artículo en Zh | MEDLINE | ID: mdl-38565504

RESUMEN

OBJECTIVE: To explore the genetic background for a patient with refractory myelodysplastic/myeloproliferative neoplasm (MDS/MPN) with co-morbid neutrophilia patient. METHODS: A MDS/MPN patient who was admitted to the First Affiliated Hospital of Nanjing Medical University in May 2021 was selected as the study subject. RNA sequencing was carried out to identify fusion genes in his peripheral blood mononuclear cells. Fusion gene sequence was searched through transcriptome-wide analysis with a STAR-fusion procedure. The novel fusion genes were verified by quantitative real-time PCR and Sanger sequencing. RESULTS: The patient, a 67-year-old male, had progressive thrombocytopenia. Based on the morphological and molecular examinations, he was diagnosed as MDS/MPN with co-morbid neutropenia, and was treated with demethylating agents and Bcl-2 inhibitors. Seventeen months after the diagnosis, he had progressed to AML. A novel fusion gene NCOR1::GLYR1 was identified by RNA-sequencing in his peripheral blood sample, which was verified by quantitative real-time PCR and Sanger sequencing. The patient had attained morphological remission after a DCAG regimen (a combinatory chemotherapy of decitabine, cytarabine, aclarubicin and granulocyte colony-stimulating factors) plus Chidamide treatment. A significant decrease in the NCOR1::GLYR1 expression was revealed by quantitative real-time PCR at post-chemotherapy evaluation. CONCLUSION: NCOR1::GLYR1 gene is considered as the pathogenic factor for the MDS/MPN patient with neutropenia.


Asunto(s)
Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Neutropenia , Masculino , Humanos , Anciano , Síndromes Mielodisplásicos/genética , Leucocitos Mononucleares , Citarabina/uso terapéutico , Co-Represor 1 de Receptor Nuclear
12.
Angew Chem Int Ed Engl ; 63(36): e202407279, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-38872356

RESUMEN

Polyradical cages are of great interest because they show very fascinating physical and chemical properties, but many challenges remain, especially for their synthesis and characterization. Herein, we present the synthesis of a polyradical cation cage 14⋅+ through post-synthetic oxidation of a redox-active phenothiazine-based Pd2L4-type coordination cage 1. It's worth noting that 1 exhibits excellent reversible electrochemical and chemical redox activity due to the introduction of a bulky 3,5-di-tert-butyl-4-methoxyphenyl substituent. The generation of 14⋅+ through reversible electrochemical oxidation is investigated by in situ UV/Vis-NIR and EPR spectroelectrochemistry. Meanwhile, chemical oxidation of 1 can also produce 14⋅+ which can be reversibly reduced back to the original cage 1, and the process is monitored by EPR and NMR spectroscopies. Eventually, we succeed in the isolation and single crystal X-ray diffraction analysis of 14⋅+, whose electronic structure and conformation are distinct to original 1. The magnetic susceptibility measurements indicate the predominantly antiferromagnetic interactions between the four phenothiazine radical cations in 14⋅+. We believe that our study including the facile synthesis methodology and in situ spectroelectrochemistry will shed some light on the synthesis and characterization of novel polyradical systems, opening more perspectives for developing functional supramolecular cages.

13.
Angew Chem Int Ed Engl ; 63(26): e202404825, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38647332

RESUMEN

Aqueous Zn-ion batteries (ZIBs) are promising next-generation energy storage devices, yet suffer from the issues of hydrogen evolution reaction (HER) and intricate side reactions on the Zn anode surface. The hydrogen (H)-bond networks play a critical role in interfacial proton transport that may closely relate to HER but are rarely investigated. Herein, we report a self-assembled monolayer (SAM) strategy which is constructed by anchoring ionic liquid cations on Ti3C2Tx substrate for HER-free Zn anode. Molecule dynamics simulations reveal that the rationally designed SAM with a high coordination number of water molecules (25-27, 4-6 for Zn2+) largely reduces the interfacial densities of H2O molecules, therefore breaking the connectivity of H-bond networks and blocking proton transport on the interface, by which the HER is suppressed. Then, a series of in situ characterizations demonstrate that negligible amounts of H2 gas are collected from the Zn@SAM-MXene anode. Consequently, the symmetric cell enables a long-cycling life of 3000 h at 1 mA cm-2 and 1000 h at 5 mA cm-2. More significantly, the stable Zn@SAM-MXene films are successfully used for coin full cells showing high-capacity retention of over 94 % after 1000 cycles and large-area (10×5 cm2) pouch cells with desired performance.

14.
Angew Chem Int Ed Engl ; : e202414089, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39221861

RESUMEN

The exploration of novel functionalized supramolecular coordination complexes (SCCs) can enable new applications in domains that include purification and sensing. In this study, employing a coordination-driven self-assembly strategy, we designed and prepared a series of benzochalcogenodiazole-based metallohelicates as high-efficiency charge transfer surface-enhanced Raman scattering (SERS) substrates, expanding the range of applications for these metallohelicates. Through structural modifications, including the substitution of single heteroatoms on ligands, replacement of coordinating metals, and alteration of ligand framework linkages, the Raman performance of these metallohelicates as substrates were systematically optimized. Notably, the SERS enhancement factors (EFs) of the metallohelicate-based SERS substrates were significantly enhanced to levels as high as 1.03 × 107, which rivals the EFs of noble metals devoid of "hot spots". Additionally, the underlying Raman enhancement mechanisms of these metallohelicates have been investigated through a combination of control experiments and theoretical calculations. This study not only demonstrates the utility of metallohelicates as SERS substrates but also offers insights and materials for the development of high-efficiency new charge transfer SERS substrates.

15.
J Biol Chem ; 298(1): 101430, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34801553

RESUMEN

Various plants use antimicrobial proteins/peptides to resist phytopathogens. In the potato, Solanum tuberosum, the plant-specific insert (PSI) domain of an aspartic protease performs this role by disrupting phytopathogen plasma membranes. However, the mechanism by which PSI selects target membranes has not been elucidated. Here, we studied PSI-induced membrane fusion, focusing on the effects of lipid composition on fusion efficiency. Membrane fusion by the PSI involves an intermediate state whereby adjacent liposomes share their bilayers. We found that increasing the concentration of negatively charged phosphatidylserine (PS) phospholipids substantially accelerated PSI-mediated membrane fusion. NMR data demonstrated that PS did not affect the binding between the PSI and liposomes but had seminal effects on the dynamics of PSI interaction with liposomes. In PS-free liposomes, the PSI underwent significant motion, which was suppressed on PS-contained liposomes. Molecular dynamics simulations showed that the PSI binds to PS-containing membranes with a dominant angle ranging from -31° to 30°, with respect to the bilayer, and is closer to the membrane surfaces. In contrast, PSI is mobile and exhibits multiple topological states on the surface of PS-free membranes. Taken together, our data suggested that PS lipids limit the motion of the anchored PSI, bringing it closer to the membrane surface and efficiently bridging different liposomes to accelerate fusion. As most phytopathogens have a higher content of negatively charged lipids as compared with host cells, these results indicate that the PSI selectively targets negatively charged lipids, which likely represents a way of distinguishing the pathogen from the host.


Asunto(s)
Proteasas de Ácido Aspártico , Fosfolípidos , Solanum tuberosum , Membrana Celular/metabolismo , Liposomas/química , Fusión de Membrana , Fosfatidilserinas/química , Fosfolípidos/química , Fosfolípidos/metabolismo , Dominios Proteicos , Solanum tuberosum/química , Solanum tuberosum/metabolismo
16.
J Am Chem Soc ; 145(9): 4934-4939, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36811995

RESUMEN

Iron porphyrin carbenes (IPCs) have been extensively recognized as the reactive intermediates in various iron porphyrin-catalyzed carbene transfer reactions. While donor-acceptor diazo compounds have been frequently used for such transformations, the structures and reactivities of donor-acceptor IPCs are less explored. To date, no crystal structures of donor-acceptor IPC complexes have been reported, and therefore, the involvement of IPC intermediacy for such transformations lacks direct evidence. Here we report the synthesis and NMR characterization of several donor-acceptor IPC complexes from iron porphyrin and corresponding donor-acceptor diazo compounds. The X-ray crystal structure of an IPC complex derived from a morpholine-substituted diazo amide was obtained. The carbene transfer reactivities of those IPCs were tested by the N-H insertion reactions with aniline or morpholine as well as the three-component reaction with aniline and γ,δ-unsaturated α-keto ester based on electrophilic trapping of an ammonium ylide intermediate. Based on these results, IPCs were identified as the real intermediates for iron porphyrin-catalyzed carbene transfer reactions from donor-acceptor diazo compounds.

17.
J Gen Virol ; 104(2)2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36802334

RESUMEN

The coat protein (CP) of plant viruses generally has multiple functions involving infection, replication, movement and pathogenicity. Functions of the CP of prunus necrotic ringspot virus (PNRSV), the causal agent of several threatening diseases of Prunus fruit trees, are poorly studied. Previously, we identified a novel virus in apple, apple necrotic mosaic virus (ApNMV), which is phylogenetically related to PNRSV and probably associated with apple mosaic disease in China. Full-length cDNA clones of PNRSV and ApNMV were constructed, and both are infectious in cucumber (Cucumis sativus L.), an experimental host. PNRSV exhibited higher systemic infection efficiency with more severe symptoms than ApNMV. Reassortment analysis of genomic RNA segments 1-3 found that RNA3 of PNRSV could enhance the long-distance movement of an ApNMV chimaera in cucumber, indicating the association of RNA3 of PNRSV with viral long-distance movement. Deletion mutagenesis of the PNRSV CP showed that the basic motif from amino acids 38 to 47 was crucial for the CP to maintain the systemic movement of PNRSV. Moreover, we found that arginine residues 41, 43 and 47 codetermine viral long-distance movement. The findings demonstrate that the CP of PNRSV is required for long-distance movement in cucumber, which expands the functions of ilarvirus CPs in systemic infection. For the first time, we identified involvement of Ilarvirus CP protein during long-distance movement.


Asunto(s)
Ilarvirus , Prunus , Ilarvirus/genética , Ilarvirus/metabolismo , ARN Viral/metabolismo , Prunus/genética , China
18.
Small ; 19(48): e2305024, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37533371

RESUMEN

Photocatalytic hydrogen production via water splitting is the subject of intense research. Photoinduced electron transfer (PET) between a photosensitizer (PS) and a proton reduction catalyst is a prerequisite step and crucial to affecting hydrogen production efficiency. Herein, three photoactive metal-organic framework (MOF) systems having two different PET processes where PS and Co(II) centers are either covalently bonded or coexisting to drive photocatalytic H2 production are built. Compared to these two intramolecular PET systems including CoII -Zn-PDTP prepared from the post-synthetic metalation toward uncoordinated pyridine N sites of Zn-PDTP and sole cobalt-based MOF Co-PDTP, the CoII (bpy)3 @Zn-PDTP system impregnated by molecular cocatalyst possessing intermolecular PET process achieves the highest H2 evolution rate of 116.8 mmol g-1 h-1 over a period of 10 h, about 7.5 and 9.3 times compared to CoII -Zn-PDTP and Co-PDTP in visible-light-driven H2 evolution, respectively. Further studies reveal that the enhanced photoactivity in CoII (bpy)3 @Zn-PDTP can be ascribed to the high charge-separation efficiency of Zn-PDTP and the synergistic intermolecular interaction between Zn-PDTP and cobalt complexes. The present work demonstrates that the rational design of PET process between MOFs and catalytic metal sites can be a viable strategy for the development of highly efficient photocatalysts with enhanced photocatalytic activities.

19.
Small ; 19(8): e2206181, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36504477

RESUMEN

Inspired by human eyes, the neuromorphic visual system employs a highly efficient imaging and recognition process, which offers tremendous advantages in image acquisition, data pre-processing, and dynamic storage. However, it is still an enormous challenge to simultaneously simulate the structure, function, and environmental adaptive behavior of the human eye based on one device. Here, a multimodal-synergistic-modulation neuromorphic imaging system based on ultraflexible synaptic transistors is successfully presented and firstly simulates the dry eye imaging behavior at the device level. Moreover, important functions of the human visual system in relation to optoelectronic synaptic plasticity, image erasure and enhancement, real-time preprocessing, and dynamic storage are simulated by versatile devices. This work not only simplifies the complexity of traditional neuromorphic visual systems, but also plays a positive role in the publicity of biomedical eye care.


Asunto(s)
Síndromes de Ojo Seco , Plasticidad Neuronal , Humanos
20.
Haematologica ; 108(8): 2146-2154, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-36700408

RESUMEN

Although classic Hodgkin lymphoma (cHL) is highly curable with current treatment paradigms, therapy fails in 10-25% of patients. This prospective multicenter phase II study attempted to investigate the efficacy and safety of the combination of tislelizumab with gemcitabine and oxaliplatin (T-GemOx) in relapsed or refractory cHL. Participants received six to eight courses of gemcitabine (1 g/m2 on day 1) and oxaliplatin (100 mg/m2 on day 1) combined with tislelizumab (200 mg on day 2) at 21-day intervals, followed by tislelizumab maintenance (every 2 months for 2 years). The main outcome measure was the best complete remission rate. As of August 2022, a total of 30 patients had been consecutively enrolled and given induction therapy. The best overall response rate and complete remission rate were 100% (95% confidence interval [CI]: 88.4-100%) and 96.7% (95% CI: 82.8-99.9%), respectively. The median duration of follow-up after initiation of T-GemOx was 15.8 months. The 12-month progression-free survival rate without autologous stem cell transplant was 96% (95% CI: 74.8-99.4%). There were 122 adverse events recorded, of which 93.4% were grade 1 or 2. Thrombocytopenia (10%) and anemia (6.7%) were the most common grade 3 or 4 adverse events. Overall, T-GemOx demonstrated promising antitumor activity with manageable toxicities as a salvage treatment for relapsed or refractory cHL. A longer follow-up duration is required to determine whether maintenance therapy with tislelizumab rather than transplantation can be curative following such a highly active regimen. This trial was registered with the Chinese Clinical Trials Registry (http://www.chictr.org.cn) on June 1, 2020, identifier ChiCTR2000033441.


Asunto(s)
Gemcitabina , Enfermedad de Hodgkin , Humanos , Oxaliplatino , Enfermedad de Hodgkin/tratamiento farmacológico , Enfermedad de Hodgkin/etiología , Estudios Prospectivos , Resultado del Tratamiento , Desoxicitidina/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
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