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1.
Nature ; 606(7913): 313-318, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35381598

RESUMO

Cross-coupling between two similar or identical functional groups to form a new C-C bond is a powerful tool to rapidly assemble complex molecules from readily available building units, as seen with olefin cross-metathesis or various types of cross-electrophile coupling1,2. The Kolbe electrolysis involves the oxidative electrochemical decarboxylation of alkyl carboxylic acids to their corresponding radical species followed by recombination to generate a new C-C bond3-12. As one of the oldest known Csp3-Csp3 bond-forming reactions, it holds incredible promise for organic synthesis, yet its use has been almost non-existent. From the perspective of synthesis design, this transformation could allow one to agnostically execute syntheses without regard to polarity or neighbouring functionality just by coupling ubiquitous carboxylates13. In practice, this promise is undermined by the strongly oxidative electrolytic protocol used traditionally since the nineteenth century5, thereby severely limiting its scope. Here, we show how a mildly reductive Ni-electrocatalytic system can couple two different carboxylates by means of in situ generated redox-active esters, termed doubly decarboxylative cross-coupling. This operationally simple method can be used to heterocouple primary, secondary and even certain tertiary redox-active esters, thereby opening up a powerful new approach for synthesis. The reaction, which cannot be mimicked using stoichiometric metal reductants or photochemical conditions, tolerates a range of functional groups, is scalable and is used for the synthesis of 32 known compounds, reducing overall step counts by 73%.


Assuntos
Ácidos Carboxílicos , Técnicas de Química Sintética , Níquel , Ácidos Carboxílicos/química , Catálise , Descarboxilação , Eletroquímica , Ésteres/química , Estrutura Molecular , Níquel/química , Oxirredução
2.
Nature ; 605(7911): 687-695, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35614246

RESUMO

The study and application of transition metal hydrides (TMHs) has been an active area of chemical research since the early 1960s1, for energy storage, through the reduction of protons to generate hydrogen2,3, and for organic synthesis, for the functionalization of unsaturated C-C, C-O and C-N bonds4,5. In the former instance, electrochemical means for driving such reactivity has been common place since the 1950s6 but the use of stoichiometric exogenous organic- and metal-based reductants to harness the power of TMHs in synthetic chemistry remains the norm. In particular, cobalt-based TMHs have found widespread use for the derivatization of olefins and alkynes in complex molecule construction, often by a net hydrogen atom transfer (HAT)7. Here we show how an electrocatalytic approach inspired by decades of energy storage research can be made use of in the context of modern organic synthesis. This strategy not only offers benefits in terms of sustainability and efficiency but also enables enhanced chemoselectivity and distinct, tunable reactivity. Ten different reaction manifolds across dozens of substrates are exemplified, along with detailed mechanistic insights into this scalable electrochemical entry into Co-H generation that takes place through a low-valent intermediate.

3.
Proc Natl Acad Sci U S A ; 120(26): e2218218120, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37339213

RESUMO

The criticality of the jamming transition responsible for amorphous solidification has been theoretically linked to the marginal stability of a thermodynamic Gardner phase. While the critical exponents of jamming appear independent of the preparation history, the pertinence of Gardner physics far from equilibrium is an open question. To fill this gap, we numerically study the nonequilibrium dynamics of hard disks compressed toward the jamming transition using a broad variety of protocols. We show that dynamic signatures of Gardner physics can be disentangled from the aging relaxation dynamics. We thus define a generic dynamic Gardner cross-over regardless of the history. Our results show that the jamming transition is always accessed by exploring increasingly complex landscape, resulting in anomalous microscopic relaxation dynamics that remains to be understood theoretically.

4.
Proc Natl Acad Sci U S A ; 120(1): e2214773120, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36580590

RESUMO

We present an extreme case of composition-modulated nanomaterial formed by selective etching (dealloying) and electrochemical refilling. The product is a coarse-grain polycrystal consisting of two interwoven nanophases, with identical crystal structures and a cube-on-cube relationship, separated by smoothly curved semicoherent interfaces with high-density misfit dislocations. This material resembles spinodal alloys structurally, but its synthesis and composition modulation are spinodal-independent. Our Cu/Au "spinodoid" alloy demonstrates superior mechanical properties such as near-theoretical strength and single-phase-like behavior, owing to its fine composition modulation, large-scale coherence of crystal lattice, and smoothly shaped three-dimensional (3D) interface morphology. As a unique extension of spinodal alloy, the spinodoid alloy reported here reveals a number of possibilities to modulate the material's structure and composition down to the nanoscale, such that further improved properties unmatchable by conventional materials can be achieved.

5.
Lancet ; 403(10445): 2720-2731, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38824941

RESUMO

BACKGROUND: Anti-PD-1 therapy and chemotherapy is a recommended first-line treatment for recurrent or metastatic nasopharyngeal carcinoma, but the role of PD-1 blockade remains unknown in patients with locoregionally advanced nasopharyngeal carcinoma. We assessed the addition of sintilimab, a PD-1 inhibitor, to standard chemoradiotherapy in this patient population. METHODS: This multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial was conducted at nine hospitals in China. Adults aged 18-65 years with newly diagnosed high-risk non-metastatic stage III-IVa locoregionally advanced nasopharyngeal carcinoma (excluding T3-4N0 and T3N1) were eligible. Patients were randomly assigned (1:1) using blocks of four to receive gemcitabine and cisplatin induction chemotherapy followed by concurrent cisplatin radiotherapy (standard therapy group) or standard therapy with 200 mg sintilimab intravenously once every 3 weeks for 12 cycles (comprising three induction, three concurrent, and six adjuvant cycles to radiotherapy; sintilimab group). The primary endpoint was event-free survival from randomisation to disease recurrence (locoregional or distant) or death from any cause in the intention-to-treat population. Secondary endpoints included adverse events. This trial is registered with ClinicalTrials.gov (NCT03700476) and is now completed; follow-up is ongoing. FINDINGS: Between Dec 21, 2018, and March 31, 2020, 425 patients were enrolled and randomly assigned to the sintilimab (n=210) or standard therapy groups (n=215). At median follow-up of 41·9 months (IQR 38·0-44·8; 389 alive at primary data cutoff [Feb 28, 2023] and 366 [94%] had at least 36 months of follow-up), event-free survival was higher in the sintilimab group compared with the standard therapy group (36-month rates 86% [95% CI 81-90] vs 76% [70-81]; stratified hazard ratio 0·59 [0·38-0·92]; p=0·019). Grade 3-4 adverse events occurred in 155 (74%) in the sintilimab group versus 140 (65%) in the standard therapy group, with the most common being stomatitis (68 [33%] vs 64 [30%]), leukopenia (54 [26%] vs 48 [22%]), and neutropenia (50 [24%] vs 46 [21%]). Two (1%) patients died in the sintilimab group (both considered to be immune-related) and one (<1%) in the standard therapy group. Grade 3-4 immune-related adverse events occurred in 20 (10%) patients in the sintilimab group. INTERPRETATION: Addition of sintilimab to chemoradiotherapy improved event-free survival, albeit with higher but manageable adverse events. Longer follow-up is necessary to determine whether this regimen can be considered as the standard of care for patients with high-risk locoregionally advanced nasopharyngeal carcinoma. FUNDING: National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, Natural Science Foundation of Guangdong Province, Overseas Expertise Introduction Project for Discipline Innovation, Guangzhou Municipal Health Commission, and Cancer Innovative Research Program of Sun Yat-sen University Cancer Center. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Anticorpos Monoclonais Humanizados , Quimiorradioterapia , Quimioterapia de Indução , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/tratamento farmacológico , Adulto , China/epidemiologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/terapia , Quimiorradioterapia/métodos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/administração & dosagem , Idoso , Cisplatino/uso terapêutico , Cisplatino/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Gencitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Desoxicitidina/administração & dosagem , Adulto Jovem , Adolescente , Intervalo Livre de Progressão
6.
J Am Chem Soc ; 146(26): 18011-18018, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38905313

RESUMO

Bioisosterism is a valuable principle exploited in drug discovery to fine-tune physicochemical properties of bioactive compounds. Functionalized 3-aryl oxetanes, as an important class of bioisosteres for benzoyl groups (highly prevalent structures in approved drugs), have been rarely utilized in agrochemicals and pharmaceuticals due to significant synthetic challenges. Here, we present a modular synthetic strategy based on the unexplored yet readily available reagents, oxetanyl trichloroacetimidates, inspired by Schmidt glycosylation, enabling easy access to a library of functionalized oxetanes. This operationally simple protocol leverages the vast existing libraries of aryl halides and various nucleophiles. The power and generality of this approach is demonstrated by late-stage functionalization of complex molecules, as well as the rapid synthesis of oxetane analogues of bioactive molecules and marketed drugs. Preliminary mechanistic study suggests that the oxygen atom in the oxetane ring plays a crucial role in stabilizing the carbocation intermediates.

7.
Plant Cell Physiol ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38988201

RESUMO

Classic genome-wide association studies (GWAS) look for associations between individual SNPs and phenotypes of interest. With the rapid progress of high-throughput genotyping and phenotyping technologies, GWAS have become increasingly powerful for detecting genetic determinants and their molecular mechanisms underpinning natural phenotypic variation. However, GWAS frequently yield results with neither expected nor promising loci, nor any significant associations. This is often because associations between SNPs and a single phenotype are confounded, for example with the environment, other traits, or complex genetic structures. Such confounding can mask true genotype-phenotype associations, or inflate spurious associations. To address these problems, numerous methods have been developed that go beyond the standard model. Such advanced GWAS models are flexible and can offer improved statistical power for understanding the genetics underlying complex traits. Despite this advantage, these models have not been widely adopted and implemented compared to the standard GWAS approach, partly because this literature is diverse and often technical. In this review, our aim is to provide an overview of the application and the benefits of various advanced GWAS models for handling complex traits and genetic structures, targeting plant biologists who wish to carry out GWAS more effectively.

8.
Anal Chem ; 96(22): 9043-9050, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38774984

RESUMO

Zearalenone (ZEN) is an extremely hazardous chemical widely existing in cereals, and its high-sensitivity detection possesses significant significance to human health. Here, the cathodic aggregation-induced electrochemiluminescence (AIECL) performance of tetraphenylethylene nanoaggregates (TPE NAs) was modulated by solvent regulation, based on which an electrochemiluminescence (ECL) aptasensor was constructed for sensitive detection of ZEN. The aggregation state and AIECL of TPE NAs were directly and simply controlled by adjusting the type of organic solvent and the fraction of water, which solved the current shortcomings of low strength and weak stability of the cathode ECL signal for TPE. Impressively, in a tetrahydrofuran-water mixed solution (volume ratio, 6:4), the relative ECL efficiency of TPE NAs reached 16.03%, which was 9.2 times that in pure water conditions, and the maximum ECL spectral wavelength was obviously red-shifted to 617 nm. In addition, "H"-shape DNA structure-mediated dual-catalyzed hairpin self-assembly (H-D-CHA) with higher efficiency by the synergistic effect between the two CHA reactions was utilized to construct a sensitive ECL aptasensor for ZEN analysis with a low detection limit of 0.362 fg/mL. In conclusion, solvent regulation was a simple and efficient method for improving the performance of AIECL materials, and the proposed ECL aptasensor had great potential for ZEN monitoring in food safety.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Medições Luminescentes , Solventes , Zearalenona , Zearalenona/análise , Zearalenona/química , Solventes/química , Estilbenos/química , Limite de Detecção , Técnicas Biossensoriais , Aptâmeros de Nucleotídeos/química
9.
Cytokine ; 173: 156423, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37979212

RESUMO

Isthmin is a polypeptide secreted by adipocytes that was first detected in Xenopus gastrula embryos. Recent studies have focused on the biological functions of isthmin in growth and development, angiogenesis, and metabolism. Distinct spatiotemporal expression of isthmin-1 (ISM-1) was observed during growth and development. ISM-1 plays an important role in the occurrence and development of cancer by regulating cell proliferation, migration, angiogenesis, and immune microenvironments. Moreover, ISM-1, as a newly identified insulin-like adipokine, increases adipocyte glucose uptake and inhibits hepatic lipid synthesis. However, the biological function of ISM-1 remains largely unknown. In this review, we highlight the structure and physiological functions of isthmin and explore its application potential, contributing to a better understanding of its function and providing prevention and treatment strategies for various diseases.


Assuntos
Trombospondinas , Proliferação de Células , Glucose , Insulina , Fígado/metabolismo , Humanos , Animais , Trombospondinas/fisiologia
10.
Chemistry ; 30(30): e202400121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38538538

RESUMO

It is vital to develop highly efficient non-doped blue organic light-emitting diodes (OLEDs) with high color purity and low-efficiency roll-off for applications in display and lighting. Herein, two blue D-A fluorophores TPA-PO and TPA-DPO are designed and synthesized, in which phenanthro[9,10-d]oxazole (PO) acts as the acceptor and triphenylamine as the donor. TPA-PO and TPA-DPO display good thermal stability and efficient luminescence efficiency in neat film. Results based on photophysical property and theoretical calculation demonstrate that TPA-PO and TPA-DPO possess the hybridized local and charge-transfer (HLCT) feature, which can utilize the triplet exciton to achieve highly efficient electroluminance (EL). The non-doped OLEDs with TPA-PO/TPA-DPO as pure emissive layer show the uniform EL emission peak at 468 nm, corresponding to CIE coordinates of (0.168, 0.187) and (0.167, 0.167), respectively. The TPA-DPO-based non-doped OLEDs provide the maximum external quantum efficiency (EQE) of 7.99 % and high exciton utility efficiency of 48.4 %~72.6 %. Moreover, the TPA-DPO-based device exhibits low-efficiency roll-off, still maintaining the EQE of 6.03 % at the high luminance of 5000 cd m-2. Those findings state clearly that PO is a promising building block of blue fluorophore with a potential HLCT feature to be applied in non-doped OLEDs.

11.
FASEB J ; 37(5): e22877, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37014317

RESUMO

Hypertrophic ligamentum flavum (LF) is a main factor responsible for lumbar spinal stenosis (LSS); however, the exact mechanisms of the pathogenesis of these processes remain unknown. This study aimed to elucidate whether circular RNAs and microRNAs regulate the pathogenesis of LF and LSS, especially focusing on circPDK1 (hsa_circ_0057105), a circRNA targeting pyruvate dehydrogenase kinase 1 and differentially expressed in LF tissues between lumbar disk herniation and LSS patients. The circPDK1/miR-4731 and miR-4731/TNXB (Tenascin XB) interactions were predicted and validated by luciferase reporter assay. Colony formation, wound-healing, and MTT assays were used for estimating cell proliferation and migration. Protein expression levels were evaluated using Western blotting. TNXB expression was verified using immunohistochemistry (IHC). Overexpressing circPDK1 promoted the proliferation, migration, and expression of fibrosis-related protein (alpha smooth muscle actin (α-SMA), lysyl oxidase like 2 (LOXL2), Collagen I, matrix metalloproteinase-2 (MMP-2) and TNXB) in LF whereas miR-4731-5p showed opposite effects. The expression of TNXB was promoted by circPDK1; contrary results were observed with miR-4731-5p. Co-overexpression of miR-4731-5p partially reversed the proliferative and fibrosis-prompting effects of circPDK1 or TNXB. The circPDK1-miR-4731-TNXB pathway may be proposed as a regulatory axis in LF hypertrophy, which might shed light on in-depth research of LSS, as well as providing a novel therapeutic target for LF hypertrophy-induced LSS.


Assuntos
Ligamento Amarelo , MicroRNAs , Humanos , RNA Circular/genética , RNA Circular/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Ligamento Amarelo/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fibrose , Hipertrofia/metabolismo
12.
Acta Pharmacol Sin ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609561

RESUMO

Proteolysis targeting chimeras (PROTACs) have emerged as revolutionary anticancer therapeutics that degrade disease-causing proteins. However, the anticancer performance of PROTACs is often impaired by their insufficient bioavailability, unsatisfactory tumor specificity and ability to induce acquired drug resistance. Herein, we propose a polymer-conjugated PROTAC prodrug platform for the tumor-targeted delivery of the most prevalent von Hippel-Lindau (VHL)- and cereblon (CRBN)-based PROTACs, as well as for the precise codelivery of a degrader and conventional small-molecule drugs. The self-assembling PROTAC prodrug nanoparticles (NPs) can specifically target and be activated inside tumor cells to release the free PROTAC for precise protein degradation. The PROTAC prodrug NPs caused more efficient regression of MDA-MB-231 breast tumors in a mouse model by degrading bromodomain-containing protein 4 (BRD4) or cyclin-dependent kinase 9 (CDK9) with decreased systemic toxicity. In addition, we demonstrated that the PROTAC prodrug NPs can serve as a versatile platform for the codelivery of a PROTAC and chemotherapeutics for enhanced anticancer efficiency and combination benefits. This study paves the way for utilizing tumor-targeted protein degradation for precise anticancer therapy and the effective combination treatment of complex diseases.

13.
Acta Pharmacol Sin ; 45(3): 517-530, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37880339

RESUMO

Malignant ventricular arrhythmia (VA) after myocardial infarction (MI) is mainly caused by myocardial electrophysiological remodeling. Brahma-related gene 1 (BRG1) is an ATPase catalytic subunit that belongs to a family of chromatin remodeling complexes called Switch/Sucrose Non-Fermentable Chromatin (SWI/SNF). BRG1 has been reported as a molecular chaperone, interacting with various transcription factors or proteins to regulate transcription in cardiac diseases. In this study, we investigated the potential role of BRG1 in ion channel remodeling and VA after ischemic infarction. Myocardial infarction (MI) mice were established by ligating the left anterior descending (LAD) coronary artery, and electrocardiogram (ECG) was monitored. Epicardial conduction of MI mouse heart was characterized in Langendorff-perfused hearts using epicardial optical voltage mapping. Patch-clamping analysis was conducted in single ventricular cardiomyocytes isolated from the mice. We showed that BRG1 expression in the border zone was progressively increased in the first week following MI. Cardiac-specific deletion of BRG1 by tail vein injection of AAV9-BRG1-shRNA significantly ameliorated susceptibility to electrical-induced VA and shortened QTc intervals in MI mice. BRG1 knockdown significantly enhanced conduction velocity (CV) and reversed the prolonged action potential duration in MI mouse heart. Moreover, BRG1 knockdown improved the decreased densities of Na+ current (INa) and transient outward potassium current (Ito), as well as the expression of Nav1.5 and Kv4.3 in the border zone of MI mouse hearts and in hypoxia-treated neonatal mouse ventricular cardiomyocytes. We revealed that MI increased the binding among BRG1, T-cell factor 4 (TCF4) and ß-catenin, forming a transcription complex, which suppressed the transcription activity of SCN5A and KCND3, thereby influencing the incidence of VA post-MI.


Assuntos
Infarto do Miocárdio , Camundongos , Animais , Infarto do Miocárdio/metabolismo , Arritmias Cardíacas/genética , Miocárdio/patologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Miócitos Cardíacos/metabolismo
14.
PLoS Genet ; 17(6): e1009653, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34181658

RESUMO

A single insulin receptor (InR) gene has been identified and extensively studied in model species ranging from nematodes to mice. However, most insects possess additional copies of InR, yet the functional significance, if any, of alternate InRs is unknown. Here, we used the wing-dimorphic brown planthopper (BPH) as a model system to query the role of a second InR copy in insects. NlInR2 resembled the BPH InR homologue (NlInR1) in terms of nymph development and reproduction, but revealed distinct regulatory roles in fuel metabolism, lifespan, and starvation tolerance. Unlike a lethal phenotype derived from NlInR1 null, homozygous NlInR2 null mutants were viable and accelerated DNA replication and cell proliferation in wing cells, thus redirecting short-winged-destined BPHs to develop into long-winged morphs. Additionally, the proper expression of NlInR2 was needed to maintain symmetric vein patterning in wings. Our findings provide the first direct evidence for the regulatory complexity of the two InR paralogues in insects, implying the functionally independent evolution of multiple InRs in invertebrates.


Assuntos
Evolução Molecular , Regulação da Expressão Gênica no Desenvolvimento , Hemípteros/genética , Proteínas de Insetos/genética , Receptor de Insulina/genética , Asas de Animais/metabolismo , Adaptação Fisiológica/genética , Animais , Sequência de Bases , Sistemas CRISPR-Cas , Metabolismo Energético/genética , Dosagem de Genes , Edição de Genes/métodos , Hemípteros/anatomia & histologia , Hemípteros/crescimento & desenvolvimento , Hemípteros/metabolismo , Proteínas de Insetos/metabolismo , Longevidade/genética , Ninfa/genética , Ninfa/crescimento & desenvolvimento , Ninfa/metabolismo , Fenótipo , Receptor de Insulina/metabolismo , Transdução de Sinais , Inanição/genética , Inanição/metabolismo , Asas de Animais/anatomia & histologia , Asas de Animais/crescimento & desenvolvimento
15.
PLoS Genet ; 17(2): e1009312, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33561165

RESUMO

Wing polymorphism is an evolutionary feature found in a wide variety of insects, which offers a model system for studying the evolutionary significance of dispersal. In the wing-dimorphic planthopper Nilaparvata lugens, the insulin/insulin-like growth factor signaling (IIS) pathway acts as a 'master signal' that directs the development of either long-winged (LW) or short-winged (SW) morphs via regulation of the activity of Forkhead transcription factor subgroup O (NlFoxO). However, downstream effectors of the IIS-FoxO signaling cascade that mediate alternative wing morphs are unclear. Here we found that vestigial (Nlvg), a key wing-patterning gene, is selectively and temporally regulated by the IIS-FoxO signaling cascade during the wing-morph decision stage (fifth-instar stage). RNA interference (RNAi)-mediated silencing of Nlfoxo increase Nlvg expression in the fifth-instar stage (the last nymphal stage), thereby inducing LW development. Conversely, silencing of Nlvg can antagonize the effects of IIS activity on LW development, redirecting wing commitment from LW to the morph with intermediate wing size. In vitro and in vivo binding assays indicated that NlFoxO protein may suppress Nlvg expression by directly binding to the first intron region of the Nlvg locus. Our findings provide a first glimpse of the link connecting the IIS pathway to the wing-patterning network on the developmental plasticity of wings in insects, and help us understanding how phenotypic diversity is generated by the modification of a common set of pattern elements.


Assuntos
Proteína Forkhead Box O1/metabolismo , Hemípteros/metabolismo , Proteínas de Insetos/metabolismo , Somatomedinas/metabolismo , Asas de Animais/crescimento & desenvolvimento , Animais , Proteína Forkhead Box O1/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Técnicas de Inativação de Genes , Ontologia Genética , Inativação Gênica , Hemípteros/genética , Hemípteros/crescimento & desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas de Insetos/genética , Íntrons , Fenótipo , Ligação Proteica , Interferência de RNA , Somatomedinas/genética , Análise Espaço-Temporal , Asas de Animais/metabolismo
16.
Zhongguo Zhong Yao Za Zhi ; 49(3): 744-753, 2024 Feb.
Artigo em Zh | MEDLINE | ID: mdl-38621878

RESUMO

This study observed the protective effect of resveratrol(Res) on ovarian function in poor ovarian response(POR) mice by regulating the Hippo signaling pathway and explored the potential mechanism of Res in inhibiting ovarian cell apoptosis. Female mice with regular estrous cycles were randomly divided into a blank group, a model group, and low-and high-dose Res groups(20 and 40 mg·kg~(-1)), with 20 mice in each group. The blank group received an equal volume of 0.9% saline solution by gavage, while the model group and Res groups received suspension of glycosides of Triptergium wilfordii(GTW) at 50 mg·kg~(-1) by gavage for two weeks to induce the model. After modeling, the low-and high-dose Res groups were continuously treated with drugs by gavage for two weeks, while the blank group and the model group received an equal volume of 0.9% saline solution by gavage. Ovulation was induced in all groups on the day following the end of treatment. Finally, 12 female mice were randomly selected from each group, and the remaining eight female mice were co-housed with male mice at a ratio of 1∶1. Changes in the estrous cycle of mice were observed using vaginal cytology smears. The number of ovulated eggs, ovarian wet weight, ovarian index, and pregnancy rate of mice were measured. The le-vels of anti-Mullerian hormone(AMH), follicle-stimulating hormone(FSH), estradiol(E_2), and luteinizing hormone(LH) in serum were determined using enzyme-linked immunosorbent assay(ELISA). Ovarian tissue morphology and ovarian cell apoptosis were observed using hematoxylin-eosin(HE) staining and terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL) staining, respectively. The protein expression levels of yes-associated protein(YAP) 1 and transcriptional coactivator with PDZ-binding motif(TAZ) were detected by immunohistochemistry(IHC), while the changes in protein expression levels of mammalian sterile 20-like kinase(MST) 1/2, large tumor suppressor(LATS) 1/2, YAP1, TAZ, B-cell lymphoma-2(Bcl-2), and Bcl-2 associated X protein(Bax) were determined by Western blot. The results showed that compared with the blank group, the model group had an increased rate of estrous cycle disruption in mice, a decreased number of normally developing ovarian follicles, an increased number of blocked ovarian follicles, increased ovarian granulosa cell apoptosis, decreased ovulation, reduced ovarian wet weight and ovarian index, increased serum FSH and LH levels, decreased AMH and E_2 levels, decreased protein expression levels of YAP1 and TAZ in ovarian tissues, increased relative expression levels of MST1/2, LATS1/2, and Bax proteins, and decreased relative expression levels of YAP1, TAZ, and Bcl-2 proteins. Additionally, the number of embryos per litter significantly decreased after co-housing. Compared with the model group, the low-and high-dose Res groups exhibited reduced estrous cycle disruption rates in mice, varying degrees of improvement in the number and morphology of ovarian follicles, reduced numbers of blocked ovarian follicles, improved ovarian granulosa cell apoptosis, increased ovulation, elevated ovarian wet weight and ovarian index, decreased serum FSH and LH levels, increased AMH and E_2 levels, elevated protein expression levels of YAP1 and TAZ in ovarian tissues, decreased relative expression levels of MST1/2, LATS1/2, and Bax proteins, and increased relative expression levels of YAP1, TAZ, and Bcl-2 proteins. Furthermore, the number of embryos per litter increased to varying degrees after co-housing. In conclusion, Res effectively inhibits ovarian cell apoptosis in mice and improves ovarian responsiveness. Its mechanism may be related to the regulation of key molecules in the Hippo pathway.


Assuntos
Via de Sinalização Hippo , Ovário , Gravidez , Camundongos , Feminino , Masculino , Animais , Proteína X Associada a bcl-2/metabolismo , Resveratrol/farmacologia , Solução Salina/metabolismo , Solução Salina/farmacologia , Hormônio Foliculoestimulante/metabolismo , Hormônio Foliculoestimulante/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Mamíferos/metabolismo
17.
J Am Chem Soc ; 145(28): 15088-15093, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37399078

RESUMO

The first practical, fully stereoselective P(V)-radical hydrophosphorylation is presented herein by using simple, limonene-derived reagent systems. A set of reagents have been developed that upon radical initiation react smoothly with olefins and other radical acceptors to generate P-chiral products, which can be further diversified (with conventional 2e- chemistry) to a range of underexplored bioisosteric building blocks. The reactions have a wide scope with excellent chemoselectivity, and the unexpected stereochemical outcome has been supported computationally and experimentally. Initial ADME studies are suggestive of the promising properties of this rarely explored chemical space.

18.
Br J Cancer ; 128(11): 2126-2139, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36977825

RESUMO

BACKGROUND: Enhancing the response rate of immunotherapy will aid in the success of cancer treatment. Here, we aimed to explore the combined effect of immunogenic radiotherapy with anti-PD-L1 treatment in immunotherapy-resistant HNSCC mouse models. METHODS: The SCC7 and 4MOSC2 cell lines were irradiated in vitro. SCC7-bearing mice were treated with hypofractionated or single-dose radiotherapy followed by anti-PD-L1 therapy. The myeloid-derived suppressive cells (MDSCs) were depleted using an anti-Gr-1 antibody. Human samples were collected to evaluate the immune cell populations and ICD markers. RESULTS: Irradiation increased the release of immunogenic cell death (ICD) markers (calreticulin, HMGB1 and ATP) in SCC7 and 4MOSC2 in a dose-dependent manner. The supernatant from irradiated cells upregulated the expression of PD-L1 in MDSCs. Mice treated with hypofractionated but not single-dose radiotherapy were resistant to tumour rechallenge by triggering ICD, when combined with anti-PD-L1 treatment. The therapeutic efficacy of combination treatment partially relies on MDSCs. The high expression of ICD markers was associated with activation of adaptive immune responses and a positive prognosis in HNSCC patients. CONCLUSION: These results present a translatable method to substantially improve the antitumor immune response by combining PD-L1 blockade with immunogenic hypofractionated radiotherapy in HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Inibidores de Checkpoint Imunológico , Células Supressoras Mieloides , Carcinoma de Células Escamosas de Cabeça e Pescoço , Animais , Humanos , Camundongos , Antígeno B7-H1/metabolismo , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Imunoterapia/métodos , Células Supressoras Mieloides/metabolismo , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico
19.
Anal Chem ; 95(2): 1686-1693, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36541619

RESUMO

Due to effective tackling of the problems of aggregation-caused quenching of traditional ECL emitters, aggregation-induced electrochemiluminescence (AIECL) has emerged as a research hotspot in aqueous detection and sensing. However, the existing AIECL emitters still encounter the bottlenecks of low ECL efficiency, poor biocompatibility, and high cost. Herein, aluminum(III)-based organic nanofibrous gels (AOGs) are used as a novel AIECL emitter to construct a rapid and ultrasensitive sensing platform for the detection of Flu A virus biomarker DNA (fDNA) with the assistance of a high-speed and hyper-efficient signal magnifier, a rigid triplex DNA walker (T-DNA walker). The proposed AOGs with three-dimensional (3D) nanofiber morphology are assembled in one step within about 15 s by the ligand 2,2':6',2″-terpyridine-4'-carboxylic acid (TPY-COOH) and cheap metal ion Al3+, which demonstrates an efficient ECL response and outstanding biocompatibility. Impressively, on the basis of loop-mediated isothermal amplification-generated hydrogen ions (LAMP-H+), the target-induced pH-responsive rigid T-DNA walker overcomes the limitations of conventional single or duplex DNA walkers in walking trajectory and efficiency due to the entanglement and lodging of leg DNA, exhibiting high stability, controllability, and walking efficiency. Therefore, AOGs with excellent AIECL performance were combined with a CG-C+ T-DNA nanomachine with high walking efficiency and stability, and the proposed "on-off" ECL biosensor displayed a low detection limit down to 23 ag·µL-1 for target fDNA. Also, the strategy provided a useful platform for rapid and sensitive monitoring of biomolecules, considerably broadening its potential applications in luminescent molecular devices, clinical diagnosis, and sensing analysis.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Nanofibras , Alumínio , Medições Luminescentes/métodos , DNA Viral , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Limite de Detecção , MicroRNAs/análise
20.
Anal Chem ; 95(2): 1454-1460, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36538530

RESUMO

Organic photoelectrochemical transistor (OPECT) bioanalytics has recently appeared as a promising route for biological measurements, which has major implications in both next-generation photoelectrochemical (PEC) bioanalysis and futuristic biorelated implementations. Via biological dissociation of materials, bioetching is a useful technique for bio-manufacturing and bioanalysis. The intersection of these two domains is expected to be a possible way to achieve innovative OPECT bioanalytics. Herein, we validate such a possibility, which is exemplified by alkaline phosphatase (ALP)-mediated bioetching of a CoOOH/BiVO4 gate for a signal-on OPECT immunoassay of human immunoglobulin G (HIgG) as the model target. Specifically, target-dependent bioetching of the upper CoOOH layer could result into an enhanced electrolyte contact and light accessibility to BiVO4, leading to the modulated response of the polymeric poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) channel that could be monitored by the channel current. The introduced biosensor achieves sensitive detection of HIgG with high selectivity and sensitivity. This work features bioetching-enabled high-efficacy OPECT bioanalysis and is anticipated to serve as a generic protocol, considering the diverse bioetching routes.


Assuntos
Fosfatase Alcalina , Técnicas Biossensoriais , Humanos , Fosfatase Alcalina/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Imunoensaio/métodos , Óxidos
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