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1.
Mol Cell ; 72(6): 1021-1034.e4, 2018 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-30472193

RESUMEN

The dynamic transcriptional regulation and interactions of human germlines and surrounding somatic cells during folliculogenesis remain unknown. Using RNA sequencing (RNA-seq) analysis of human oocytes and corresponding granulosa cells (GCs) spanning five follicular stages, we revealed unique features in transcriptional machinery, transcription factor networks, and reciprocal interactions in human oocytes and GCs that displayed developmental-stage-specific expression patterns. Notably, we identified specific gene signatures of two cell types in particular developmental stage that may reflect developmental competency and ovarian reserve. Additionally, we uncovered key pathways that may concert germline-somatic interactions and drive the transition of primordial-to-primary follicle, which represents follicle activation. Thus, our work provides key insights into the crucial features of the transcriptional regulation in the stepwise folliculogenesis and offers important clues for improving follicle recruitment in vivo and restoring fully competent oocytes in vitro.


Asunto(s)
Comunicación Celular/genética , Células de la Granulosa/fisiología , Oocitos/fisiología , Folículo Ovárico/fisiología , Reserva Ovárica/genética , Transcriptoma , Adulto , Animales , Biología Computacional , Bases de Datos Genéticas , Femenino , Perfilación de la Expresión Génica/métodos , Regulación del Desarrollo de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Ratones , Folículo Ovárico/citología , Transducción de Señal/genética , Análisis de la Célula Individual , Especificidad de la Especie , Transcripción Genética , Adulto Joven
2.
Nat Chem Biol ; 19(4): 468-477, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36635564

RESUMEN

Membrane dynamics are important to the integrity and function of mitochondria. Defective mitochondrial fusion underlies the pathogenesis of multiple diseases. The ability to target fusion highlights the potential to fight life-threatening conditions. Here we report a small molecule agonist, S89, that specifically promotes mitochondrial fusion by targeting endogenous MFN1. S89 interacts directly with a loop region in the helix bundle 2 domain of MFN1 to stimulate GTP hydrolysis and vesicle fusion. GTP loading or competition by S89 dislodges the loop from the GTPase domain and unlocks the molecule. S89 restores mitochondrial and cellular defects caused by mitochondrial DNA mutations, oxidative stress inducer paraquat, ferroptosis inducer RSL3 or CMT2A-causing mutations by boosting endogenous MFN1. Strikingly, S89 effectively eliminates ischemia/reperfusion (I/R)-induced mitochondrial damage and protects mouse heart from I/R injury. These results reveal the priming mechanism for MFNs and provide a therapeutic strategy for mitochondrial diseases when additional mitochondrial fusion is beneficial.


Asunto(s)
Dinámicas Mitocondriales , Proteínas de Transporte de Membrana Mitocondrial , Ratones , Animales , Proteínas de Transporte de Membrana Mitocondrial/análisis , Proteínas de Transporte de Membrana Mitocondrial/química , Proteínas de Transporte de Membrana Mitocondrial/genética , Mitocondrias , Hidrólisis , Guanosina Trifosfato/análisis , Guanosina Trifosfato/farmacología , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/análisis , Proteínas Mitocondriales/farmacología
3.
Chem Soc Rev ; 53(7): 3384-3456, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38411207

RESUMEN

The scientific community has witnessed extensive developments and applications of organoboron compounds as synthetic elements and metal-free catalysts for the construction of small molecules, macromolecules, and functional materials over the last two decades. This review highlights the achievements of organoboron-mediated polymerizations in the past several decades alongside the mechanisms underlying these transformations from the standpoint of the polymerization mode. Emphasis is placed on free radical polymerization, Lewis pair polymerization, ionic (cationic and anionic) polymerization, and polyhomologation. Herein, alkylborane/O2 initiating systems mediate the radical polymerization under ambient conditions in a controlled/living manner by careful optimization of the alkylborane structure or additives; when combined with Lewis bases, the selected organoboron compounds can mediate the Lewis pair polymerization of polar monomers; the bicomponent organoboron-based Lewis pairs and bifunctional organoboron-onium catalysts catalyze ring opening (co)polymerization of cyclic monomers (with heteroallenes, such as epoxides, CO2, CO, COS, CS2, episulfides, anhydrides, and isocyanates) with well-defined structures and high reactivities; and organoboranes initiate the polyhomologation of sulfur ylides and arsonium ylides providing functional polyethylene with different topologies. The topological structures of the produced polymers via these organoboron-mediated polymerizations are also presented in this review mainly including linear polymers, block copolymers, cyclic polymers, and graft polymers. We hope the summary and understanding of how organoboron compounds mediate polymerizations can inspire chemists to apply these principles in the design of more advanced organoboron compounds, which may be beneficial for the polymer chemistry community and organometallics/organocatalysis community.

4.
Plant Physiol ; 191(1): 772-788, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36342207

RESUMEN

Plants sense and respond to fluctuating temperature and light conditions during the circadian cycle; however, the molecular mechanism underlying plant adaptability during daytime warm conditions remains poorly understood. In this study, we reveal that the ectopic regulation of a HEAT RESPONSIVE PROTEIN (GhHRP) controls the adaptation and survival of cotton (Gossypium hirsutum) plants in response to warm conditions via modulating phytohormone signaling. Increased ambient temperature promptly enhanced the binding of the phytochrome interacting factor 4 (GhPIF4)/ethylene-insensitive 3 (GhEIN3) complex to the GhHRP promoter to increase its mRNA level. The ectopic expression of GhHRP promoted the temperature-dependent accumulation of GhPIF4 transcripts and hypocotyl elongation by triggering thermoresponsive growth-related genes. Notably, the upregulation of the GhHRP/GhPIF4 complex improved plant growth via modulating the abundance of Arabidopsis thaliana auxin biosynthetic gene YUCCA8 (AtYUC8)/1-aminocyclopropane-1-carboxylate synthase 8 (AtACS8) for fine-tuning the auxin/ethylene interplay, ultimately resulting in decreased ethylene biosynthesis. GhHRP thus protects chloroplasts from photo-oxidative bursts via repressing AtACS8 and AtACS7 and upregulating AtYUC8 and the heat shock transcription factors (HSFA2), heat shock proteins (HSP70 and HSP20). Strikingly, the Δhrp disruption mutant exhibited compromised production of HSP/YUC8 that resulted in an opposite phenotype with the loss of the ability to respond to warm conditions. Our results show that GhHRP is a heat-responsive signaling component that assists plants in confronting the dark phase and modulates auxin signaling to rescue growth under temperature fluctuations.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Ácidos Indolacéticos/metabolismo , Gossypium/genética , Gossypium/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Etilenos/metabolismo , Arabidopsis/metabolismo , Respuesta al Choque Térmico , Transducción de Señal/genética , Regulación de la Expresión Génica de las Plantas
5.
J Org Chem ; 89(12): 8334-8341, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38860473

RESUMEN

Here, a Cu2(OH)2CO3-catalyzed hydroboration reaction of 1,1-disubstituted α,ß-unsaturated compounds has been developed. The reaction was carried out using water as a solvent at room temperature except for N-monosubstituted α,ß-unsaturated amides. This method is applicable to diverse 1,1-disubstituted α,ß-unsaturated ketones, esters, and amides, showing excellent reactivity (up to 98% yield). Gram-scale experiments and functional group transformations further demonstrated the practicality of this method.

6.
Phys Chem Chem Phys ; 26(9): 7475-7481, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38353594

RESUMEN

Theory and experiment have revealed that spin-orbit coupling (SOC) strongly depends on the relativistic effect in topological insulators (TIs), while the influence of orbitals is always ignored. Herein, we provide a direct way of controlling effective SOC with the help of orbital effects, reducing the dependence on elements. Taking 5d W2CO2 and 4d Mo2CO2 MXenes as a specific example, we predict that by decreasing the hybridization strength of W atoms with C or O atoms in 2D W2CO2, the nontrivial bandgaps at the Γ-point are directly enhanced. The weak hybridization of W atoms with ligand elements enhances the electron localization of degenerate d-orbitals of three groups under the triangular prism crystal field, inducing stronger on-site Coulomb repulsion that enhances orbital polarization as well as boosts the SOC effect. Meanwhile, similar results have also been observed in 4d Mo2CO2. This implies that the orbital effects are an efficient and straightforward way to control the nontrivial bandgap in 2D MXene TIs. Our work not only provides an alternative perspective on designing large nontrivial bandgaps but also brings a possibility to control the SOC effect for TI devices.

7.
Artículo en Inglés | MEDLINE | ID: mdl-38904855

RESUMEN

Drawing on the stressor-perception-coping-response model of stress, this study examined the associations between negative life events, present-moment awareness, problem-solving, and perceived stress among rural adolescents, focusing specifically on gender differences. Using a cross-sectional design, 3519 Chinese rural adolescents completed measures assessing negative life events, present-moment awareness, problem-solving, and perceived stress. Structural equation modeling was employed to examine the hypothesized serial mediation model. The results revealed a positive association between negative life events and perceived stress in rural adolescents, which was serially mediated by present-moment awareness and problem-solving. Furthermore, significant gender differences were observed. Specifically, girls exhibited larger effects than boys in the overall effect of negative life events on perceived stress, the indirect effect of present-moment awareness, and the serial mediating effect. These findings suggest that present-moment awareness and problem-solving may serve as crucial mechanisms for understanding rural adolescents' perceived stress in response to negative life events, particularly among female rural adolescents.

8.
J Virol ; 96(6): e0202721, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35107377

RESUMEN

Marek's disease virus (MDV) is a member of the genus Mardivirus in the subfamily Alphaherpesvirinae. There are three different serotypes of MDV designated as MDV-1 (Gallid herpesvirus type 2), MDV-2 (Gallid herpesvirus type 3), and MDV-3 (Meleagrid herpesvirus 1, herpesvirus of turkeys, HVT). MDV-1 is the only serotype that induces Marek's disease (MD), a lymphoproliferative disorder resulting in aggressive T-cell lymphomas and paralytic symptoms. In the lymphomas and lymphoblastoid cell lines (LCL) derived from them, MDV establishes latent infection with limited viral gene expression. The latent viral genome in LCL can be activated by co-cultivation with chicken embryo fibroblast (CEF) monolayers. MSB-1, one of the first MDV-transformed LCL established from the splenic lymphoma, is distinct in harboring both the oncogenic MDV-1 and non-oncogenic MDV-2 viruses. Following the successful application of CRISPR/Cas9 editing approach for precise knockdown of the MDV-1 genes in LCL, we describe here the targeted deletion of MDV-2 glycoprotein B (gB) in MSB-1 cells. Due to the essential nature of gB for infectivity, the production of MDV-2 plaques on CEF was completely abolished in the MDV-2-gB-deleted MSB-1 cells. Our study has demonstrated that the CRISPR/Cas9 system can be used for targeted inactivation of the co-infecting MDV-2 without affecting the MDV-1 in the MSB-1 cell line. Successful inactivation of MDV-2 demonstrated here also points toward the possibility of using targeted gene editing as an antiviral strategy against pathogenic MDV-1 and other viruses infecting chickens. IMPORTANCE Marek's disease (MD) is a lymphoproliferative disease of chickens characterized by rapid-onset lymphomas in multiple organs and by infiltration into peripheral nerves, causing paralysis. Lymphoblastoid cell lines (LCL) derived from MD lymphomas have served as valuable resources to improve understanding of distinct aspects of virus-host interactions in transformed cells including transformation, latency, and reactivation. MDV-transformed LCL MSB-1, derived from spleen lymphoma induced by the BC-1 strain of MDV, has a unique feature of harboring an additional non-pathogenic MDV-2 strain HPRS-24. By targeted deletion of essential gene glycoprotein B from the MDV-2 genome within the MSB-1 cells, we demonstrated the total inhibition of MDV-2 virus replication on co-cultivated CEF, with no effect on MDV-1 replication. The identified viral genes critical for reactivation/inhibition of viruses will be useful as targets for development of de novo disease resistance in chickens to avian pathogens.


Asunto(s)
Herpesvirus Gallináceo 3 , Linfoma , Enfermedad de Marek , Proteínas del Envoltorio Viral , Animales , Sistemas CRISPR-Cas , Línea Celular , Embrión de Pollo , Pollos , Herpesvirus Gallináceo 3/genética , Linfoma/veterinaria , Linfoma/virología , Proteínas del Envoltorio Viral/genética
9.
Eur Arch Psychiatry Clin Neurosci ; 273(5): 1085-1094, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36484845

RESUMEN

Rumination and childhood trauma are related to depressive symptoms in clinical and non-clinical individuals. This is the first study aimed to test the mediating effect of rumination on the relationship between childhood trauma and depressive symptoms in schizophrenia patients. A total of 313 schizophrenia patients were recruited in the present study. The 17-item Hamilton Depression Rating Scale (HAMD-17) was adopted to evaluate depressive symptoms, the short-form Childhood Trauma Questionnaire (CTQ-SF) and the 10-item Ruminative response scale (RRS-10) were utilized to assess the childhood trauma and rumination in patients, respectively. Our results showed that 168 schizophrenia patients (53.67%) had comorbid depressive symptoms. These patients with depressive symptoms had higher levels of childhood trauma [both CTQ-SF total scores and emotional abuse (EA), emotional neglect (EN), physical neglect (PN) subscale scores] and rumination (both RRS-10 total scores and brooding, reflection subscale scores) compared to patients without depressive symptoms. The stepwise logistic regression analysis identified that EN (OR 1.196, P = 0.003), PN (OR 1.1294, P < 0.001), brooding (OR 1.291, P < 0.001) and reflection (OR 1.481, P < 0.001) could independently predict the depressive symptoms in schizophrenia patients. Moreover, RRS-10 and its subscale scores could mediate the relationship between depressive symptoms and childhood trauma, especially EA, EN and PN in schizophrenia. Our preliminary findings suggest that the rigorous assessment and psychosocial interventions of rumination are important to alleviate the influence of childhood trauma on depressive symptoms in schizophrenia patients.


Asunto(s)
Experiencias Adversas de la Infancia , Maltrato a los Niños , Esquizofrenia , Niño , Humanos , Esquizofrenia/complicaciones , Esquizofrenia/diagnóstico , Depresión/etiología , Maltrato a los Niños/psicología , Encuestas y Cuestionarios
10.
Molecules ; 28(14)2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37513482

RESUMEN

A chitosan/poly(vinyl alcohol)-stabilized copper nanoparticle (CP@Cu NPs) was used as a heterogeneous catalyst for the borylation of α, ß-unsaturated ketones, MBH alcohols, and MBH esters in mild conditions. This catalyst not only demonstrated remarkable efficiency in synthesizing organoboron compounds but also still maintained excellent reactivity and stability even after seven recycled uses of the catalyst. This methodology provides a gentle and efficient approach to synthesize the organoboron compounds by efficiently constructing carbon-boron bonds.

11.
J Am Chem Soc ; 144(43): 19896-19909, 2022 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-36256447

RESUMEN

Switchable catalysis, in combination with epoxide-involved ring-opening (co)polymerization, is a powerful technique that can be used to synthesize various oxygen-rich block copolymers. Despite intense research in this field, the sequence-controlled polymerization from epoxide congeners has never been realized due to their similar ring-strain which exerts a decisive influence on the reaction process. Recently, quaternary ammonium (or phosphonium)-containing bifunctional organoboron catalysts have been developed by our group, showing high efficiency for various epoxide conversions. Herein, we, for the first time, report an operationally simple pathway to access well-defined polyether-block-polycarbonate copolymers from mixtures of epoxides by switchable catalysis, which was enabled through thermodynamically and kinetically preferential ring-opening of terminal epoxides or internal epoxides under different atmospheres (CO2 or N2) using one representative bifunctional organoboron catalyst. This strategy shows a broad substrate scope as it is suitable for various combinations of terminal epoxides and internal epoxides, delivering corresponding well-defined block copolymers. NMR, MALDI-TOF, and gel permeation chromatography analyses confirmed the successful construction of polyether-block-polycarbonate copolymers. Kinetic studies and density functional theory calculations elucidate the reversible selectivity between different epoxides in the presence/absence of CO2. Moreover, by replacing comonomer CO2 with cyclic anhydride, the well-defined polyether-block-polyester copolymers can also be synthesized. This work provides a rare example of sequence-controlled polymerization from epoxide mixtures, broadening the arsenal of switchable catalysis that can produce oxygen-rich polymers in a controlled manner.


Asunto(s)
Dióxido de Carbono , Compuestos Epoxi , Compuestos Epoxi/química , Cinética , Dióxido de Carbono/química , Oxígeno , Catálisis , Polímeros/química , Carbonatos
12.
Anal Chem ; 94(30): 10730-10736, 2022 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-35853147

RESUMEN

This study developed a novel luminescent assay for kinase activity using metal-organic coordination polymer nanoparticles (Tb/ATP-Zn) as the probe. Tb/ATP-Zn, self-assembled by adenosine triphosphate (ATP), Zn2+, and Tb3+, is non-luminescent. Protein kinase A (PKA) can catalyze the transformation of ATP within Tb/ATP-Zn nanoparticles to adenosine diphosphate (ADP), which in turn effectively sensitizes the luminescence of Tb3+. Based on this mechanism, Tb/ATP-Zn can realize the facile luminescent "turn-on" sensing of protein kinase activity without the use of external ATP and substrate peptide. Under optimized conditions, the fluorescence intensities of Tb/ATP-Zn at 550 nm are linear with the PKA activity within a range of 0.3-1.5 U·µL-1. The LOD (S/N = 3) of this method is down to 0.001 U·µL-1. The presented assay also features high selectivity, long-term stability, fast response, and convenient operation. Furthermore, Tb/ATP-Zn was successfully employed for monitoring PKA activity in cell lysis solutions. Probe Tb/ATP-Zn is thus expectable to be a powerful tool for the practical study of PKA in relevant biological events.


Asunto(s)
Elementos de la Serie de los Lantanoides , Nanopartículas del Metal , Adenosina Trifosfato , Luminiscencia , Mediciones Luminiscentes/métodos , Polímeros , Proteínas Quinasas
13.
Acc Chem Res ; 54(23): 4434-4448, 2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34806374

RESUMEN

ConspectusElectron-deficient boron-based catalysts with metal-free but metallomimetic characteristics provide a versatile platform for chemical transformations. However, their catalytic performance is usually lower than that of the corresponding metal-based catalysts. Furthermore, many elaborate organoboron compounds are produced via time-consuming multistep syntheses with low yields, presenting a formidable challenge for large-scale applications of these catalysts. Given this context, the development of organoboron catalysts with the combined advantages of high efficiency and easy preparation is of critical importance.Therefore, we envisioned that the construction of a dynamic Lewis multicore system (DLMCS) by integrating the Lewis acidic boron center(s) and a Lewis basic ammonium salt in one molecule would be particularly efficient for on-demand applications because of the intramolecular synergistic effect. This Account summarizes our recent efforts in developing modular organoboron catalysts with unprecedented activities for several chemical transformations. A series of mono-, di-, tri-, and tetranuclear organoboron catalysts was readily designed and prepared in nearly quantitative yields over two steps using commercially available feedstocks. Notably, these catalysts can be modularly tailored by fine control over the electrophilic property of the Lewis acidic boron center(s), electronic and steric effects of the electropositive ammonium cation, linker length between the boron center and the ammonium cation, the number of boron centers, and the nucleophilic anion. This modular design allows systematic manipulation of the reactivity and efficacy of the catalysts, thus optimizing suitable catalysts for versatile chemical transformations. These include the coupling of CO2 and epoxides, copolymerization of CO2 and epoxides, ring-opening polymerization (ROP) of epoxides, and ring-opening copolymerization (ROCOP) of epoxides and cyclic anhydrides.The utilization of mononuclear organoboron catalysts provided a turnover frequency of 11050 h-1 for the CO2/propylene oxide coupling reaction, an unprecedented efficiency of 5.0 kg of polymer/g of catalyst for the copolymerization of CO2 and cyclohexene oxide, and a record-breaking catalytic efficiency of 7.4 kg of polymer/g of catalyst for the ROCOP of epoxides with cyclic anhydrides. A turnover number of 56500 was observed at a catalyst loading of 10 ppm for the ROP of epoxides using the dinuclear catalysts. The tetranuclear organoboron catalysts realized the previously intractable task of the copolymerization of CO2 and epichlorohydrin, producing poly(chloropropylene carbonate) with the highest molecular weight of 36.5 kg/mol reported to date.Furthermore, the study revealed that the interaction between the dynamic Lewis multicore, that is, the intramolecular synergistic effect between the boron center(s) and the quaternary ammonium salt, plays a key role in mediating the catalytic activity and selectivity. This was based on investigations of the crystal structures of the catalysts, key intermediates, reaction kinetics, and density functional theory calculations. The modular tactics for the construction of organoboron catalysts presented in this Account should inspire more advanced catalyst designs.

14.
Microb Cell Fact ; 21(1): 212, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36243714

RESUMEN

BACKGROUND: Linalool is a monoterpenoid, also a vital silvichemical with commercial applications in cosmetics, flavoring ingredients, and medicines. Regulation of mevalonate (MVA) pathway metabolic flux is a common strategy to engineer Saccharomyces cerevisiae for efficient linalool production. However, metabolic regulation of the MVA pathway is complex and involves competition for central carbon metabolism, resulting in limited contents of target metabolites. RESULTS: In this study, first, a truncated linalool synthase (t26AaLS1) from Actinidia arguta was selected for the production of linalool in S. cerevisiae. To simplify the complexity of the metabolic regulation of the MVA pathway and increase the flux of isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP), we introduced the two-step isopentenyl utilization pathway (IUP) into S. cerevisiae, which could produce large amounts of IPP/DMAPP. Further, the S. cerevisiae IDI1 (ecoding isopentenyl diphosphate delta-isomerase) and ERG20F96W-N127W (encoding farnesyl diphosphate synthase) genes were integrated into the yeast genome, combined with the strategies of copy number variation of the t26AaLS1 and ERG20F96W-N127W genes to increase the metabolic flux of the downstream IPP, as well as optimization of isoprenol and prenol concentrations, resulting in a 4.8-fold increase in the linalool titer. Eventually, under the optimization of carbon sources and Mg2+ addition, a maximum linalool titer of 142.88 mg/L was obtained in the two-phase extractive shake flask fermentation. CONCLUSIONS: The results show that the efficient synthesis of linalool in S. cerevisiae could be achieved through a two-step pathway, gene expression adjustment, and optimization of culture conditions. The study may provide a valuable reference for the other monoterpenoid production in S. cerevisiae.


Asunto(s)
Ácido Mevalónico , Saccharomyces cerevisiae , Monoterpenos Acíclicos , Carbono/metabolismo , Variaciones en el Número de Copia de ADN , Difosfatos/metabolismo , Geraniltranstransferasa/genética , Geraniltranstransferasa/metabolismo , Hemiterpenos , Ingeniería Metabólica/métodos , Ácido Mevalónico/metabolismo , Monoterpenos/metabolismo , Compuestos Organofosforados , Pentanoles , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
15.
J Org Chem ; 87(5): 3145-3155, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35073078

RESUMEN

The bifunctional thiourea catalyst system with both electrophilic and nucleophilic centers has been certified to be effective for fixing CO2 under mild reaction conditions; however, many questions remain, especially concerning the relationship between structure and performance. Herein, we systematically studied a series of such bifunctional catalysts with different chain lengths, nucleophilic anions, and substituents, which impact obvious influence on the catalytic performance. The activation energies of catalysts with different chain lengths are calculated via in situ IR. On this basis, we disclosed for the first time that the spacer length of tetramethylene -(CH2)6- is the optimal spatial effect for the coupling of epoxides and CO2. Particularly, the single crystal X-ray diffraction analysis of the molecular structures of the bifunctional catalyst C8 indicated the discovery of the existence of interaction force between the sulfur atom on the thiourea group and one hydrogen atom on the benzene ring, as well as the intermolecular hydrogen bonding interaction of the bromide (Br-) and two NH groups on the thiourea group. The catalyst structure performance, direct observation of the crystal structure, the thermodynamic study, and a wide range of substrates (12 examples) should be informative on the optimization of the existing catalysts or the design of new catalysts in the future.

16.
Epilepsy Behav ; 135: 108904, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36095876

RESUMEN

OBJECTIVE: The management of pregnant women with epilepsy (WWE) treated with antiepileptic drugs (AEDs) polytherapy poses a great challenge. The purpose of this study was to evaluate the major congenital malformations (MCMs) associated with AED polytherapy, to assess the impacts of polytherapy regimens on seizure control and breastfeeding, and to determine the potential predictors for pregnancy outcomes. METHODS: This study was based on prospectively acquired data from a registry enrolling WWE in early pregnancy from Feb 2010 to July 2019, in which 123 pregnancies in 110 WWE were exposed to 27 different AED combinations. RESULTS: There were 123 pregnancies in 110 WWE analyzed in our study. The live birth rate was 86.2 % and the risk of MCMs was 10.4 %. Multivariate analysis indicated that prenatal exposure to phenobarbital (odds ratio [OR], 17.424; 95 %CI, 1.510-201.067; P = 0.022) and topiramate (OR, 9.469; 95 %CI, 1.149-62.402; P = 0.036) was associated with increased risk of MCMs. Valproate (OR, 4.441; 95 %CI, 1.165-16.934; P = 0.029), phenobarbital (OR, 13.636; 95 %CI, 2.146-86.660; P = 0.006) and topiramate (OR, 7.527; 95 %CI, 1.764-32.118; P = 0.006) were significantly correlated with adverse pregnancy outcomes. Among 67 pregnancies in four combinations over 10 patients, 15 (22.4 %) remained seizure free through pregnancy, seizure frequency increased in 17 (25.4 %), decreased in 24 (35.8 %) women, in 26 (38.8 %) remained unchanged. Only 23.6 % of mothers undertook exclusive breastfeeding. Planned pregnancy was the only independent factor significantly associated with decreased risk of adverse pregnancy outcomes (OR, 0.139; 95 % CI, 0.051-0.382; P < 0.001). Notably, no adverse pregnancy outcome was recorded in pregnancies exposed to the combination of lamotrigine plus levetiracetam. CONCLUSION: Prenatal exposure to the combinations containing valproate, phenobarbital, or topiramate was associated with increased risk of adverse pregnant outcomes. AED-related teratogenicity may be reduced by planned pregnancy in WWE exposed to polytherapy. Our findings also suggest the combination of lamotrigine and levetiracetam seems to be most desirable to balance seizure control and fetal safety.


Asunto(s)
Epilepsia , Complicaciones del Embarazo , Efectos Tardíos de la Exposición Prenatal , Anticonvulsivantes/efectos adversos , Epilepsia/inducido químicamente , Epilepsia/tratamiento farmacológico , Femenino , Humanos , Lamotrigina/uso terapéutico , Levetiracetam/uso terapéutico , Masculino , Fenobarbital/efectos adversos , Embarazo , Complicaciones del Embarazo/inducido químicamente , Complicaciones del Embarazo/tratamiento farmacológico , Resultado del Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Sistema de Registros , Topiramato/uso terapéutico , Ácido Valproico/efectos adversos
17.
Arch Insect Biochem Physiol ; 110(1): e21878, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35181948

RESUMEN

Coreoidea (Insecta: Hemiptera: Heteroptera) is a widely distributed and agriculturally important bugs. However, the phylogeny of Coreoidea lacked consensus on higher-level relationships and several studies by comparative morphological characters and molecular data suggested the non-monophyly of two families: Coreidae and Alydidae. The mitochondrial genome (mitogenome) has long been thought to be a significant marker to understand phylogenetic relationships, but the mitogenome in Alydidae is scarce to date. In the present study, we gathered the mitogenomes of 28 species from four families of Coreoidea excluding Hyocephalidae (Alydidae, Coreidae, Rhopalidae, and Stenocephalidae), including four newly sequenced mitogenomes of Alydidae, and conducted mitogenomic organization and phylogenetic studies. We used maximum likelihood and Bayesian inference methods to infer the higher-level phylogeny from the perspective of mitogenomes, primarily to investigate the phylogenetic relationship betweeen Coreidae and Alydidae. We add evidence that neither Alydidae nor Coreidae are monophyletic based on mitogenomes. Newly sequenced mitogenomes of Alydidae have traditional gene structure and gene rearrangement was not found. Alydinae was always recovered as closely related to Pseudophloeinae of the coreid subfamily with high support. The placement of the coreid subfamily Hydarinae and alydid subfamily Micrelytrinae are unstable depending on approach used. In terms of the length and nucleotide composition of the protein coding genes in mitogenomes, Pseudophloeinae and Hydarinae of coreid were more similar to Alydidae. The unsettled classification issues of Coreidae and Alydidae by mitogenomes were demonstrated in this work, indicating that further study is needed.


Asunto(s)
Genoma Mitocondrial , Heterópteros , Animales , Secuencia de Bases , Teorema de Bayes , Heterópteros/genética , Filogenia
18.
Int J Mol Sci ; 24(1)2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36613903

RESUMEN

JMJD8 is a protein from the JMJD family that only has the JmjC domain. Studies on the function of JMJD8 indicate that JMJD8 is involved in signaling pathways, including AKT/NF-κB, and thus affects cell proliferation and development. Here, we reported the activity of JMJD8 as a non-histone demethylase. We investigated the demethylation of JMJD8 on trimethylated lysine of AKT1 in vivo and in vitro using trimethylated AKT1 short peptide and AKT1 protein, and we tracked the regulation of JMJD8 on AKT1 activity at the cellular level. The results showed that JMJD8, a mini lysine demethylase, altered AKT1 protein function via changing its degree of methylation.


Asunto(s)
Histona Demetilasas con Dominio de Jumonji , Lisina , Lisina/metabolismo , Histona Demetilasas con Dominio de Jumonji/metabolismo , Transducción de Señal , Metilación , FN-kappa B/metabolismo
19.
Int J Mol Sci ; 23(19)2022 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-36232572

RESUMEN

Avian leukosis virus (ALV) induces B-cell lymphomas and other malignancies in chickens through insertional activation of oncogenes, and c-myc activation has been commonly identified in ALV-induced tumors. Using ALV-transformed B-lymphoma-derived HP45 cell line, we applied in situ CRISPR-Cas9 editing of integrated proviral long terminal repeat (LTR) to examine the effects on gene expression and cell proliferation. Targeted deletion of LTR resulted in significant reduction in expression of a number of LTR-regulated genes including c-myc. LTR deletion also induced apoptosis of HP45 cells, affecting their proliferation, demonstrating the significance of LTR-mediated regulation of critical genes. Compared to the global effects on expression and functions of multiple genes in LTR-deleted cells, deletion of c-myc had a major effect on the HP45 cells proliferation with the phenotype similar to the LTR deletion, demonstrating the significance of c-myc expression in ALV-induced lymphomagenesis. Overall, our studies have not only shown the potential of targeted editing of the LTR for the global inhibition of retrovirus-induced transformation, but also have provided insights into the roles of LTR-regulated genes in ALV-induced neoplastic transformation.


Asunto(s)
Virus de la Leucosis Aviar , Animales , Virus de la Leucosis Aviar/genética , Línea Celular , Proliferación Celular/genética , Pollos/genética , Provirus/genética , Secuencias Repetidas Terminales/genética
20.
Molecules ; 27(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36432064

RESUMEN

Here, we describe the preparation of copper nanoparticles that are stabilized on a chitosan composite film (CP@Cu). This material could catalyze the 1,6-hydroboration reactions of p-quinone methides with B2pin2 as a boron source under mild conditions. This reaction exhibited very good functional group compatibility, and the organoboron compounds that were formed could easily be converted into corresponding hydroxyl products with good to excellent yields. This newly developed methodology provides an efficient and sequential pathway for the synthesis of gem-disubstituted methanols.


Asunto(s)
Quitosano , Indolquinonas , Nanopartículas , Cobre
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