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1.
Genes Dev ; 35(7-8): 512-527, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766982

RESUMO

Epithelioid hemangioendothelioma (EHE) is a genetically homogenous vascular sarcoma that is a paradigm for TAZ dysregulation in cancer. EHE harbors a WWTR1(TAZ)-CAMTA1 gene fusion in >90% of cases, 45% of which have no other genetic alterations. In this study, we used a first of its kind approach to target the Wwtr1-Camta1 gene fusion to the Wwtr1 locus, to develop a conditional EHE mouse model whereby Wwtr1-Camta1 is controlled by the endogenous transcriptional regulators upon Cre activation. These mice develop EHE tumors that are indistinguishable from human EHE clinically, histologically, immunohistochemically, and genetically. Overall, these results demonstrate unequivocally that TAZ-CAMTA1 is sufficient to drive EHE formation with exquisite specificity, as no other tumor types were observed. Furthermore, we fully credential this unique EHE mouse model as a valid preclinical model for understanding the role of TAZ dysregulation in cancer formation and for testing therapies directed at TAZ-CAMTA1, TAZ, and YAP/TAZ signaling.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Carcinogênese/genética , Modelos Animais de Doenças , Fusão Gênica , Hemangioendotelioma Epitelioide/genética , Hemangioendotelioma Epitelioide/patologia , Transativadores/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteínas de Ligação ao Cálcio/genética , Humanos , Camundongos , Transdução de Sinais/genética , Transativadores/genética
2.
Genes Chromosomes Cancer ; 63(2): e23226, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38380774

RESUMO

Epithelioid hemangioendothelioma (EHE) is a rare endothelial sarcoma associated with a high incidence of metastases and for which there are no standard treatment options. Based on disease-defining mutations, most EHEs are classified into two subtypes: WWTR1::CAMTA1-fused EHE or YAP1::TFE3-fused EHE. However, rare non-canonical fusions have been identified in clinical samples of EHE cases and are challenging to classify. In this study, we report the identification of a novel WWTR1::TFE3 fusion variant in an EHE patient using targeted RNA sequencing. Histologically, the tumor exhibited hybrid morphological characteristics between WWTR1::CAMTA1-fused EHE and YAP1::TFE3-fused EHE. In addition to the driver fusion, there were six additional secondary mutations identified, including a loss-of-function FANCA mutation. Furthermore, in vitro studies were conducted to investigate the tumorigenic function of the WWTR1::TFE3 fusion protein in NIH3T3 cells and demonstrated that WWTR1::TFE3 promotes colony formation in soft agar. Finally, as the wild-type WWTR1 protein relies on binding the TEAD family of transcription factors to affect gene transcription, mutation of the WWTR1 domain of the fusion protein to inhibit such binding abrogates the transformative effect of WWTR1::TFE3. Overall, we describe a novel gene fusion in EHE with a hybrid histological appearance between the two major genetic subtypes of EHE. Further cases of this very rare subtype of EHE will need to be identified to fully elucidate the clinical and pathological characteristics of this unusual subtype of EHE.


Assuntos
Hemangioendotelioma Epitelioide , Transativadores , Humanos , Camundongos , Animais , Transativadores/genética , Hemangioendotelioma Epitelioide/genética , Hemangioendotelioma Epitelioide/patologia , Células NIH 3T3 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fusão Gênica , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional
3.
J Biol Chem ; 299(7): 104858, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37236356

RESUMO

Asthenozoospermia characterized by decreased sperm motility is a major cause of male infertility, but the majority of the etiology remains unknown. Here, we showed that the cilia and flagella associated protein 52 (Cfap52) gene was predominantly expressed in testis and its deletion in a Cfap52 knockout mouse model resulted in decreased sperm motility and male infertility. Cfap52 knockout also led to the disorganization of the midpiece-principal piece junction of the sperm tail but had no effect on the axoneme ultrastructure in spermatozoa. Furthermore, we found that CFAP52 interacted with the cilia and flagella associated protein 45 (CFAP45) and knockout of Cfap52 decreased the expression level of CFAP45 in sperm flagellum, which further disrupted the microtubule sliding produced by dynein ATPase. Together, our studies demonstrate that CFAP52 plays an essential role in sperm motility by interacting with CFAP45 in sperm flagellum, providing insights into the potential pathogenesis of the infertility of the human CFAP52 mutations.


Assuntos
Cílios , Infertilidade Masculina , Animais , Humanos , Masculino , Camundongos , Cílios/metabolismo , Flagelos/genética , Flagelos/metabolismo , Infertilidade Masculina/metabolismo , Camundongos Knockout , Proteínas/metabolismo , Sêmen , Motilidade dos Espermatozoides , Cauda do Espermatozoide/metabolismo , Cauda do Espermatozoide/patologia , Espermatozoides/metabolismo
4.
Glob Chang Biol ; 30(5): e17287, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38695768

RESUMO

While droughts predominantly induce immediate reductions in plant carbon uptake, they can also exert long-lasting effects on carbon fluxes through associated changes in leaf area, soil carbon, etc. Among other mechanisms, shifts in carbon allocation due to water stress can contribute to the legacy effects of drought on carbon fluxes. However, the magnitude and impact of these allocation shifts on carbon fluxes and pools remain poorly understood. Using data from a wet tropical flux tower site in French Guiana, we demonstrate that drought-induced carbon allocation shifts can be reliably inferred by assimilating Net Biosphere Exchange (NBE) and other observations within the CARbon DAta MOdel fraMework. This model-data fusion system allows inference of optimized carbon and water cycle parameters and states from multiple observational data streams. We then examined how these inferred shifts affected the duration and magnitude of drought's impact on NBE during and after the extreme event. Compared to a static allocation scheme analogous to those typically implemented in land surface models, dynamic allocation reduced average carbon uptake during drought recovery by a factor of 2.8. Additionally, the dynamic model extended the average recovery time by 5 months. The inferred allocation shifts influenced the post-drought period by altering foliage and fine root pools, which in turn modulated gross primary productivity and heterotrophic respiration for up to a decade. These changes can create a bust-boom cycle where carbon uptake is enhanced some years after a drought, compared to what would have occurred under drought-free conditions. Overall, allocation shifts accounted for 65% [45%-75%] of drought legacy effects in modeled NBE. In summary, drought-induced carbon allocation shifts can play a substantial role in the enduring influence of drought on cumulative land-atmosphere CO2 exchanges and should be accounted for in ecosystem models.


Assuntos
Ciclo do Carbono , Secas , Clima Tropical , Guiana Francesa , Florestas , Carbono/metabolismo , Modelos Teóricos
5.
Eur J Nutr ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878202

RESUMO

PURPOSE: Women with gestational diabetes mellitus (GDM) or obesity are vulnerable to impaired gestational cardiovascular health (CVH) and cardiovascular disease (CVD) in the future. It is unclear if prenatal vitamin D supplementation improves gestational CVH, especially in women at high risk for developing CVD. Our goal was to find out if vitamin D supplementation could protect against gestational CVH, including the women with GDM or obesity. DESIGN: We randomly assigned women with a serum 25(OH)D concentration < 75 nmol/L to receive 1600 IU/d (intervention group) or 400 IU/d (control group) of vitamin D3 for two months at 24-28 weeks' gestation. The primary outcome was gestational CVH marks (lipids, inflammatory cytokines, endothelial function). RESULTS: There were 1537 participants divided into the intervention (N = 766) and control groups (N = 771). No baseline differences existed among study groups in CVH markers. At the two-month visit, the intervention group's HDL-C levels (2.01 ± 0.39 VS 1.96 ± 0.39 mmol/L) were significantly higher than those of the control group, while the hs-CRP levels were significantly lower (3.28 ± 2.02 VS 3.64 ± 2.42 mg/L). Subgroup analysis found that HDL-C, TC, hs-CRP, E-Selectin, and SBP were improved in the intervention group among women with GDM or overweight/obesity, and the improvement was not found in women without GDM or overweight/obesity. Vitamin D supplementation significantly decreased the mean triglyceride-glucose index at the two-month visit in women with GDM. CONCLUSIONS: Vitamin D supplementation at mid-gestation might optimize the gestational CVH status for pregnant women, particularly the women with GDM or obesity, which is advantageous for later-life primary prevention of CVD. CLINICAL TRIAL REGISTRATION: The Chinese Clinical Trial Registry (ChiCTR2100051914, 10/9/2021, Prospective registered, https://www.chictr.org.cn/showproj.aspx?proj=134700 ).

6.
J Nat Prod ; 87(4): 1036-1043, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38600636

RESUMO

Triterpenoids are a type of specialized metabolites that exhibit a wide range of biological activities. However, the availability of some minor triterpenoids in nature is limited, which has hindered our understanding of their pharmacological potential. To overcome this limitation, heterologous biosynthesis of triterpenoids in yeast has emerged as a promising and time-efficient production platform for obtaining these minor compounds. In this study, we analyzed the transcriptomic data of Enkianthus chinensis to identify one oxidosqualene cyclase (EcOSC) gene and four CYP716s. Through heterologous expression of these genes in yeast, nine natural pentacyclic triterpenoids, including three skeleton products (1-3) produced by one multifunctional OSC and six minor oxidation products (4-9) catalyzed by CYP716s, were obtained. Of note, we discovered that CYP716E60 could oxidize ursane-type and oleanane-type triterpenoids to produce 6ß-OH derivatives, marking the first confirmed C-6ß hydroxylation in an ursuane-type triterpenoid. Compound 9 showed moderate inhibitory activity against NO production and dose-dependently reduced IL-1ß and IL-6 production at the transcriptional and protein levels. Compounds 1, 2, 8, and 9 exhibited moderate hepatoprotective activity with the survival rates of HepG2 cells from 61% to 68% at 10 µM.


Assuntos
Anti-Inflamatórios , Sistema Enzimático do Citocromo P-450 , Transferases Intramoleculares , Triterpenos , Triterpenos/farmacologia , Triterpenos/química , Humanos , Sistema Enzimático do Citocromo P-450/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Estrutura Molecular , Saccharomyces cerevisiae , Hidroxilação , Células Hep G2 , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Substâncias Protetoras/farmacologia , Substâncias Protetoras/química
7.
Environ Res ; 249: 118466, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38354882

RESUMO

Global outbreaks and the spread of viral diseases in the recent years have led to a rapid increase in the usage of antiviral drugs (ATVs), the residues and metabolites of which are discharged into the natural environment, posing a serious threat to human health. There is an urgent need to develop sensitive and rapid detection tools for multiple ATVs. In this study, we developed a highly sensitive electrochemical sensor comprising a glassy carbon electrode (GCE) modified with graphitized hydroxylated multi-walled carbon nanotubes (G-MWCNT-OH) and 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6, IL) for the detection of six ATVs including famciclovir (FCV), remdesivir (REM), favipiravir (FAV), hydroxychloroquine sulfate (HCQ), cepharanthine (CEP) and molnupiravir (MOL). The morphology and structure of the G-MWCNT-OH/IL nanocomposites were characterized comprehensively, and the electroactive surface area and electron conductivity of G-MWCNT-OH/IL/GCE were determined using cyclic voltammetry and electrochemical impedance spectroscopy. The thermodynamic stability and non-covalent interactions between the G-MWCNT-OH and IL were evaluated through quantum chemical simulation calculations, and the mechanism of ATV detection using the G-MWCNT-OH/IL/GCE was thoroughly examined. The detection conditions were optimized to improve the sensitivity and stability of electrochemical sensors. Under the optimal experimental conditions, the G-MWCNT-OH/IL/GCE exhibited excellent electrocatalytic performance and detected the ATVs over a wide concentration range (0.01-120 µM). The limit of detections (LODs) were 42.3 nM, 55.4 nM, 21.9 nM, 15.6 nM, 10.6 nM, and 3.2 nM for FCV, REM, FAV, HCQ, CEP, and MOL, respectively. G-MWCNT-OH/IL/GCE was also highly stable and selective to the ATVs in the presence of multiple interfering analytes. This sensor exhibited great potential for enabling the quantitative detection of multiple ATVs in actual water environment.


Assuntos
Antivirais , Técnicas Eletroquímicas , Líquidos Iônicos , Nanotubos de Carbono , Antivirais/análise , Antivirais/química , Nanotubos de Carbono/química , Líquidos Iônicos/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Limite de Detecção , Eletrodos , Grafite/química
8.
Cell Mol Life Sci ; 81(1): 1, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038747

RESUMO

Multiple morphological abnormalities of the flagella (MMAF) is a severe disease of male infertility, while the pathogenetic mechanisms of MMAF are still incompletely understood. Previously, we found that the deficiency of Ccdc38 might be associated with MMAF. To understand the underlying mechanism of this disease, we identified the potential partner of this protein and found that the coiled-coil domain containing 146 (CCDC146) can interact with CCDC38. It is predominantly expressed in the testes, and the knockout of this gene resulted in complete infertility in male mice but not in females. The knockout of Ccdc146 impaired spermiogenesis, mainly due to flagellum and manchette organization defects, finally led to MMAF-like phenotype. Furthermore, we demonstrated that CCDC146 could interact with both CCDC38 and CCDC42. It also interacts with intraflagellar transport (IFT) complexes IFT88 and IFT20. The knockout of this gene led to the decrease of ODF2, IFT88, and IFT20 protein levels, but did not affect CCDC38, CCDC42, or ODF1 expression. Additionally, we predicted and validated the detailed interactions between CCDC146 and CCDC38 or CCDC42, and built the interaction models at the atomic level. Our results suggest that the testis predominantly expressed gene Ccdc146 is essential for sperm flagellum biogenesis and male fertility, and its mutations might be associated with MMAF in some patients.


Assuntos
Infertilidade Masculina , Proteínas Associadas aos Microtúbulos , Cauda do Espermatozoide , Animais , Masculino , Camundongos , Fertilidade/genética , Proteínas de Choque Térmico/metabolismo , Infertilidade Masculina/metabolismo , Camundongos Knockout , Sêmen , Cauda do Espermatozoide/metabolismo , Cauda do Espermatozoide/patologia , Espermatozoides/metabolismo , Testículo/metabolismo , Proteínas Associadas aos Microtúbulos/genética
9.
Sensors (Basel) ; 24(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38676102

RESUMO

Partially impaired sensor arrays pose a significant challenge in accurately estimating signal parameters. The occurrence of bad data is highly probable, resulting in random loss of source information and substantial performance degradation in parameter estimation. In this paper, a tensor variational sparse Bayesian learning (TVSBL) method is proposed for the estimate of direction of arrival (DOA) and polarization parameters jointly based on a conformal polarization sensitive array (CPSA), taking into account scenarios with the partially impaired sensor array. First, a sparse tensor-based received data model is developed for CPSAs that incorporates bad data. Then, a column vector detection method is proposed to diagnose the positions of the impaired sensors. In scenarios involving partially impaired sensor arrays, a low-rank matrix completion method is employed to recover the random loss of signal information. Finally, variational sparse Bayesian learning (VSBL) and minimum eigenvector methods are utilized sequentially to obtain the DOA and polarization parameters estimation, successively. Furthermore, the Cramér-Rao bound is given for the proposed method. Simulation results validated the effectiveness of the proposed method.

10.
J Asian Nat Prod Res ; 26(4): 452-464, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37655543

RESUMO

Six previously undescribed prenylated C6-C3 derivatives (1-6) were isolated from the root of Illicium ternstroemioides A. C. Smith. Their structures were elucidated based on extensive spectroscopic analyses (UV, IR, 1D and 2D NMR, and HRESIMS). The absolute configurations of 1-3 were determined using electronic circular dichroism (ECD), and Mo2(OAc)4 induced circular dichroism (ICD). Compound 3 exhibited weak activity against Coxsackievirus B3 with an IC50 value of 33.3 µM, and compound 5 exhibited more potent activity against Coxsackievirus B3 with an IC50 value of 6.4 µM.


Assuntos
Illicium , Illicium/química , Estrutura Molecular , Espectroscopia de Ressonância Magnética , Dicroísmo Circular , Antivirais/farmacologia
11.
J Asian Nat Prod Res ; : 1-13, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885306

RESUMO

Three new prenylated C6-C3 compounds (1-3), together with two known prenylated C6-C3 compounds (4-5) and one known C6-C3 derivative (6), were isolated from the roots of Illicium brevistylum A. C. Smith. The structures of 1-3 were elucidated by spectroscopic methods including 1D and 2D NMR, HRESIMS, CD experiments and ECD calculations. The structure of illibrefunone A (1) was confirmed by single-crystal X-ray diffraction analysis. All compounds were evaluated in terms of their anti-inflammatory potential on nitric oxide (NO) generation in lipopolysaccharide-stimulated murine RAW264.7 macrophages and murine BV2 microglial cells, antiviral activity against Coxsackievirus B3 (CVB3) and influenza virus A/Hanfang/359/95 (H3N2). Compounds 3 and 4 exhibited potent inhibitory effects on the production of NO in RAW 264.7 cells with IC50 values of 20.57 and 12.87 µM respectively, which were greater than those of dexamethasone (positive control). Compounds 1 and 4-6 exhibited weak activity against Coxsackievirus B3, with IC50 values ranging from 25.87 to 33.33 µM.

12.
J Asian Nat Prod Res ; 26(2): 204-213, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38213077

RESUMO

Three new cadinane sesquiterpenes (1-3) and three known sesquiterpenes were isolated from the stems and branches of Illicium ternstroemioides A. C. Smith. The structures of the new compounds were elucidated by extensive analysis of spectroscopic and HRESIMS data. The structures of illiternins A-C (1-3) were confirmed by single crystal X-ray diffraction, allowing for the determination of their absolute configurations. Compounds 3 and 6 exhibited antiviral activity against Coxsackievirus B3 with IC50 values of 33.3 and 57.7 µM, respectively.


Assuntos
Illicium , Sesquiterpenos , Illicium/química , Estrutura Molecular , Sesquiterpenos Policíclicos , Sesquiterpenos/química
13.
Molecules ; 29(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38792116

RESUMO

Noble metals have become a research hotspot for the oxidation of light alkanes due to their low ignition temperature and easy activation of C-H; however, sintering and a high price limit their industrial applications. The preparation of effective and low-noble-metal catalysts still presents profound challenges. Herein, we describe how a Ru@CoMn2O4 spinel catalyst was synthesized via Ru in situ doping to promote the activity of propane oxidation. Ru@CoMn2O4 exhibited much higher catalytic activity than CoMn2O4, achieving 90% propane conversion at 217 °C. H2-TPR, O2-TPD, and XPS were used to evaluate the catalyst adsorption/lattice oxygen activity and the adsorption and catalytic oxidation capacity of propane. It could be concluded that Ru promoted synergistic interactions between cobalt and manganese, leading to electron transfer from the highly electronegative Ru to Co2+ and Mn3+. Compared with CoMn2O4, 0.1% Ru@CoMn2O4, with a higher quantity of lattice oxygen and oxygen mobility, possessed a stronger capability of reducibility, which was the main reason for the significant increase in the activity of Ru@CoMn2O4. In addition, intermediates of the reaction between adsorbed propane and lattice oxygen on the catalyst were monitored by in situ DRIFTS. This work highlights a new strategy for the design of a low-noble-metal catalyst for the efficient oxidation of propane.

14.
Molecules ; 29(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474556

RESUMO

Chemotherapy is a well-established method for treating cancer, but it has limited effectiveness due to its high dosage and harmful side effects. To address this issue, researchers have explored the use of photothermal agent nanoparticles as carriers for precise drug release in vivo. In this study, three different sizes of polydopamine nanoparticles (PDA-1, PDA-2, and PDA-3) were synthesized and evaluated. PDA-2 was selected for its optimal size, encapsulation rate, and drug loading rate. The release of the drug from PDA-2@TAX was tested at different pH and NIR laser irradiation levels. The results showed that PDA-2@TAX released more readily in an acidic environment and exhibited a high photothermal conversion efficiency when exposed to an 808 nm laser. In vitro experiments on ovarian cancer cells demonstrated that PDA-2@TAX effectively inhibited cell proliferation, highlighting its potential for synergistic chemotherapy-photothermal treatment.


Assuntos
Hipertermia Induzida , Indóis , Nanopartículas , Neoplasias Ovarianas , Polímeros , Quercetina/análogos & derivados , Humanos , Feminino , Fototerapia/métodos , Hipertermia Induzida/métodos , Neoplasias Ovarianas/tratamento farmacológico , Doxorrubicina/farmacologia
15.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1690-1698, 2024 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-38621953

RESUMO

Styrax is a commonly used imported traditional Chinese medicinal material in China. It was introduced to China in the Han Dynasty and was first described as a traditional Chinese medicine in Miscellaneous Records of Famous Physicians(Ming Yi Bie Lu). In this paper, by combing ancient and modern Chinese and foreign herbal medicine books and modern literature, combined with the results of field investigations on the origin of Styrax, the changes of Styrax involving the name, quality evaluation, origin, place of origin, and harvesting and processing were systematically verified. The results show that since ancient times, the origin and place of origin of Styrax have been unclear. The medical scientists of all dynasties in China have evaluated the quality of Styrax from four aspects: texture, viscosity, odor concentration, and color. The varieties of Styrax changed twice. The first change may have occurred during the Sui and Tang Dynasties, and the base changed from Styrax officinalis to Liquidambar orientalis. The second change was in modern times, and the base changed from L. orientalis to L. styraciflua. At the same time, the place of origin changed for the first time, from Turkey, Syria, and other countries in southern Asia Minor to Honduras, Guatemala, and other countries in Central America and southern North America. This paper studied the historical evolution of Styrax in terms of quality evaluation, origin, place of origin, character, and harvesting and processing. At the same time, it summarized the application of Styrax in the western countries, which can provide a historical basis for the further development and utilization of Styrax.


Assuntos
Medicamentos de Ervas Chinesas , Plantas Medicinais , Styrax , Medicina Tradicional Chinesa , Medicina Herbária , China
16.
Angew Chem Int Ed Engl ; 63(13): e202315674, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38327006

RESUMO

Sesquiterpene synthases (STPSs) catalyze carbocation-driven cyclization reactions that can generate structurally diverse hydrocarbons. The deprotonation-reprotonation process is widely used in STPSs to promote structural diversity, largely attributable to the distinct regio/stereoselective reprotonations. However, the molecular basis for reprotonation regioselectivity remains largely understudied. Herein, we analyzed two highly paralogous STPSs, Artabotrys hexapetalus (-)-cyperene synthase (AhCS) and ishwarane synthase (AhIS), which catalyze reactions that are distinct from the regioselective protonation of germacrene A (GA), resulting in distinct skeletons of 5/5/6 tricyclic (-)-cyperene and 6/6/5/3 tetracyclic ishwarane, respectively. Isotopic labeling experiments demonstrated that these protonations occur at C3 and C6 of GA in AhCS and AhIS, respectively. The cryo-electron microscopy-derived AhCS complex structure provided the structural basis for identifying different key active site residues that may govern their functional disparity. The structure-guided mutagenesis of these residues resulted in successful functional interconversion between AhCS and AhIS, thus targeting the three active site residues [L311-S419-C458]/[M311-V419-A458] that may act as a C3/C6 reprotonation switch for GA. These findings facilitate the rational design or directed evolution of STPSs with structurally diverse skeletons.


Assuntos
Alquil e Aril Transferases , Sesquiterpenos , Microscopia Crioeletrônica , Sesquiterpenos/química , Catálise , Domínio Catalítico , Alquil e Aril Transferases/genética
17.
Anal Chem ; 95(40): 14842-14852, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37779463

RESUMO

Liquid chromatography-mass spectrometry (LC-MS) is widely used in the detection of pesticide residues. However, the detection sensitivity of low-polarity pesticides by commonly used electrospray ionization may be severely suppressed, which greatly affects the limit of detection and repeatability. Herein, a plasma-excited nebulizer gas-assisted electrospray ionization (PENG-ESI) device has been developed. By introducing the discharge plasma formed by Tesla coil into the electrospray nebulizer gas channel, the sensitivity of low-polarity pesticides was significantly increased while maintaining sensitivity to polar pesticides. Under the optimized conditions, the limit of detection for S-bioallethrin was achieved at the level of 100 pg/g with good linearity (R2 > 0.99) and precision (RSD ≤ 4.61%). The matrix effect of a series of spiked matrix samples is less than 13.1%. Finally, different pyrethroid pesticide residues were successfully analyzed without separation, highlighting that the technology has potential application prospects in food quality control, environmental monitoring, and other fields.

18.
Small ; 19(23): e2207576, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36905244

RESUMO

Dysregulation of microRNAs (miRs) is the hallmark of triple-negative breast cancer (TNBC), which is closely involved with its growth, metastasis, and recurrence. Dysregulated miRs are promising targets for TNBC therapy, however, targeted and accurate regulation of multiple disordered miRs in tumors is still a great challenge. Here, a multi-targeting and on-demand non-coding RNA regulation nanoplatform (MTOR) is reported to precisely regulate disordered miRs, leading to dramatical suppression of TNBC growth, metastasis, and recurrence. With the assistance of long blood circulation, ligands of urokinase-type plasminogen activator peptide and hyaluronan located in multi-functional shells enable MTOR to actively target TNBC cells and breast cancer stem cell-like cells (BrCSCs). After entering TNBC cells and BrCSCs, MTOR is subjected to lysosomal hyaluronidase-induced shell detachment, leading to an explosion of the TAT-enriched core, thereby enhancing nuclear targeting. Subsequently, MTOR could precisely and simultaneously downregulate microRNA-21 expression and upregulate microRNA-205 expression in TNBC. In subcutaneous xenograft, orthotopic xenograft, pulmonary metastasis, and recurrence TNBC mouse models, MTOR shows remarkably synergetic effects on the inhibition of tumor growth, metastasis, and recurrence due to its on-demand regulation of disordered miRs. This MTOR system opens a new avenue for on-demand regulation of disordered miRs against growth, metastasis, and recurrence of TNBC.


Assuntos
MicroRNAs , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/metabolismo , Linhagem Celular Tumoral , MicroRNAs/genética , Mama , Serina-Treonina Quinases TOR/metabolismo , Regulação Neoplásica da Expressão Gênica , Proliferação de Células
19.
Glob Chang Biol ; 29(10): 2759-2775, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36799318

RESUMO

Large across-model spread in simulating land carbon (C) dynamics has been ubiquitously demonstrated in model intercomparison projects (MIPs), and became a major impediment in advancing climate change prediction. Thus, it is imperative to identify underlying sources of the spread. Here, we used a novel matrix approach to analytically pin down the sources of across-model spread in transient peatland C dynamics in response to a factorial combination of two atmospheric CO2 levels and five temperature levels. We developed a matrix-based MIP by converting the C cycle module of eight land models (i.e., TEM, CENTURY4, DALEC2, TECO, FBDC, CASA, CLM4.5 and ORCHIDEE) into eight matrix models. While the model average of ecosystem C storage was comparable to the measurement, the simulation differed largely among models, mainly due to inter-model difference in baseline C residence time. Models generally overestimated net ecosystem production (NEP), with a large spread that was mainly attributed to inter-model difference in environmental scalar. Based on the sources of spreads identified, we sequentially standardized model parameters to shrink simulated ecosystem C storage and NEP to almost none. Models generally captured the observed negative response of NEP to warming, but differed largely in the magnitude of response, due to differences in baseline C residence time and temperature sensitivity of decomposition. While there was a lack of response of NEP to elevated CO2 (eCO2 ) concentrations in the measurements, simulated NEP responded positively to eCO2 concentrations in most models, due to the positive responses of simulated net primary production. Our study used one case study in Minnesota peatland to demonstrate that the sources of across-model spreads in simulating transient C dynamics can be precisely traced to model structures and parameters, regardless of their complexity, given the protocol that all the matrix models were driven by the same gross primary production and environmental variables.


Assuntos
Carbono , Ecossistema , Dióxido de Carbono , Mudança Climática , Simulação por Computador
20.
Chemistry ; 29(10): e202202915, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36404599

RESUMO

Organic donor-acceptor complexes as new organic semiconductor class have attracted wide attention, due to their potential applications in functional optoelectronics. Herein, we present two new charge transfer cocrystals of di-cyanodiazafluorene -perylene (DCPE) and di-cyanodiazaflfluorene-pyrene (DCPY) through a rational cocrystal-engineering strategy. Although they are both 1 : 1 mixed stacking cocrystals with similar chemical structures, the DCPE cocrystal possesses a non-centrosymmetric space group and narrower band gap compared to DCPY cocrystal, because of the non-covalent bonding variation. The electrostatic potential accumulated in the lateral facets leads to highly twisted DCPE nanobelts, and the small band gap causes near infrared fluorescence. Meanwhile, the DCPY crystals with centrosymmetric space groups and weaker intermolecular interactions exhibited an untwisted morphology and red emission. This study will be helpful for the design and understanding of functional cocrystal materials that can be used in flexible micro/nano-mechanics, mechanical energy, and optical devices.

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