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1.
J Cell Sci ; 137(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38345101

RESUMO

Understanding how biophysical and biochemical microenvironmental cues together influence the regenerative activities of muscle stem cells and their progeny is crucial in strategizing remedies for pathological dysregulation of these cues in aging and disease. In this study, we investigated the cell-level influences of extracellular matrix (ECM) ligands and culture substrate stiffness on primary human myoblast contractility and proliferation within 16 h of plating and found that tethered fibronectin led to stronger stiffness-dependent responses compared to laminin and collagen. A proteome-wide analysis further uncovered cell metabolism, cytoskeletal and nuclear component regulation distinctions between cells cultured on soft and stiff substrates. Interestingly, we found that softer substrates increased the incidence of myoblasts with a wrinkled nucleus, and that the extent of wrinkling could predict Ki67 (also known as MKI67) expression. Nuclear wrinkling and Ki67 expression could be controlled by pharmacological manipulation of cellular contractility, offering a potential cellular mechanism. These results provide new insights into the regulation of human myoblast stiffness-dependent contractility response by ECM ligands and highlight a link between myoblast contractility and proliferation.


Assuntos
Matriz Extracelular , Membrana Nuclear , Humanos , Antígeno Ki-67/metabolismo , Matriz Extracelular/metabolismo , Mioblastos/metabolismo , Proliferação de Células
2.
Development ; 150(14)2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37485540

RESUMO

Accurate chromosome segregation, monitored by the spindle assembly checkpoint (SAC), is crucial for the production of euploid cells. Previous in vitro studies by us and others showed that Mad2, a core member of the SAC, performs a checkpoint function in oocyte meiosis. Here, through an oocyte-specific knockout approach in mouse, we reconfirmed that Mad2-deficient oocytes exhibit an accelerated metaphase-to-anaphase transition caused by premature degradation of securin and cyclin B1 and subsequent activation of separase in meiosis I. However, it was surprising that the knockout mice were completely fertile and the resulting oocytes were euploid. In the absence of Mad2, other SAC proteins, including BubR1, Bub3 and Mad1, were normally recruited to the kinetochores, which likely explains the balanced chromosome separation. Further studies showed that the chromosome separation in Mad2-null oocytes was particularly sensitive to environmental changes and, when matured in vitro, showed chromosome misalignment, lagging chromosomes, and aneuploidy with premature separation of sister chromatids, which was exacerbated at a lower temperature. We reveal for the first time that Mad2 is dispensable for proper chromosome segregation but acts to mitigate environmental stress in meiotic oocytes.


Assuntos
Proteínas de Ciclo Celular , Fuso Acromático , Animais , Camundongos , Proteínas de Ciclo Celular/metabolismo , Fuso Acromático/metabolismo , Proteínas Mad2/genética , Proteínas Mad2/metabolismo , Segregação de Cromossomos/genética , Oócitos/metabolismo , Cinetocoros/metabolismo , Meiose/genética
3.
Virol J ; 21(1): 116, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783310

RESUMO

OBJECTIVE: Cystic echinococcosis (CE) represents a profoundly perilous zoonotic disease. The advent of viral macrogenomics has facilitated the exploration of hitherto uncharted viral territories. In the scope of this investigation, our objective is to scrutinize disparities in the intestinal microbiotic ecosystems of canines dwelling in elevated terrains and those afflicted by Echinococcus infection, employing the tool of viral macrogenomics. METHODS: In this study, we collected a comprehensive total of 1,970 fecal samples from plateau dogs infected with Echinococcus, as well as healthy control plateau dogs from the Yushu and Guoluo regions in the highland terrain of China. These samples were subjected to viral macrogenomic analysis to investigate the viral community inhabiting the canine gastrointestinal tract. RESULTS: Our meticulous analysis led to the identification of 136 viral genomic sequences, encompassing eight distinct viral families. CONCLUSION: The outcomes of this study hold the potential to enhance our comprehension of the intricate interplay between hosts, parasites, and viral communities within the highland canine gut ecosystem. Through the examination of phage presence, it may aid in early detection or assessment of infection severity, providing valuable insights into Echinococcus infection and offering prospects for potential treatment strategies.


Assuntos
Doenças do Cão , Equinococose , Echinococcus , Fezes , Microbioma Gastrointestinal , Animais , Cães , Equinococose/veterinária , Doenças do Cão/parasitologia , Doenças do Cão/microbiologia , Doenças do Cão/virologia , China , Fezes/parasitologia , Fezes/microbiologia , Fezes/virologia , Echinococcus/genética , Echinococcus/isolamento & purificação , Genoma Viral , Vírus/classificação , Vírus/isolamento & purificação , Vírus/genética
4.
Nanotechnology ; 35(18)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38271731

RESUMO

Tunable phonon transport properties of two-dimensional materials are desirable for effective heat management in various application scenarios. Here, we demonstrate by first-principles calculations and Boltzmann transport theory that the lattice thermal conductivity of siligene could be efficiently engineered by forming various stacking configurations. Unlike few-layer graphene, the stacked siligenes are found to be covalently bonded along the out-of-plane direction, which leads to unique dependence of the thermal conductivity on both the stacking order and layer number. Due to the restricted flexural phonon scattering induced by the horizontal reflection symmetry, the AA stacking configuration of bilayer siligene exhibits obviously higher thermal conductivity compared with the AB stacking. In addition, we observe increasing thermal conductivity with the layer number, as evidenced by the reduced phonon scattering phase space and Grüneisen parameter. Interestingly, the Fuchs-Sondheimer model works well for the thickness-dependent thermal conductivity of stacked siligenes.

5.
Eur Arch Otorhinolaryngol ; 281(6): 3157-3166, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38503971

RESUMO

PURPOSE: The optimal treatment strategy for oropharyngeal cancer (OPC) is undetermined. We aim to compare the survival outcomes of OPC patients treated with upfront surgery versus definitive radiotherapy (RT). METHODS: A total of 8057 cases were retrieved from the Surveillance, Epidemiology, and End Results database. Primary endpoints were cancer-specific and noncancer mortalities, which were estimated using cumulative incidence function and compared by Gray's test. Univariate and multivariate Fine-Gray subdistribution hazard models were used to estimate the effects of treatment modality on mortality. Subgroup analyses were performed in propensity-score-matched cohorts. All the analyses were conducted separately in human papillomavirus (HPV)-negative and HPV-positive cohorts. RESULTS: In the HPV-negative cohort, definitive RT was independently associated with increased risk of cancer-specific mortality (adjusted subdistribution hazard ratio [SHR], 1.31; 95% confidence interval [CI], 1.05-1.64; P = 0.017) and noncancer mortality (adjusted SHR, 1.59; 95% CI 1.13-2.25; P = 0.008). In the HPV-positive cohort, definitive RT was independently associated with increased risk of cancer-specific mortality (adjusted SHR, 1.51; 95% CI 1.23-1.85; P < 0.001) and noncancer mortality (adjusted SHR, 1.53; 95% CI 1.11-2.12; P = 0.009). CONCLUSION: Upfront surgery is a superior treatment modality compared with definitive RT in terms of lowering cancer-specific and noncancer mortality in OPC patients, regardless of HPV status. Further prospective clinical trials are needed to confirm our findings.


Assuntos
Neoplasias Orofaríngeas , Programa de SEER , Humanos , Neoplasias Orofaríngeas/radioterapia , Neoplasias Orofaríngeas/mortalidade , Neoplasias Orofaríngeas/cirurgia , Neoplasias Orofaríngeas/virologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Medição de Risco , Infecções por Papillomavirus/radioterapia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/mortalidade , Pontuação de Propensão , Estudos Retrospectivos , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia
6.
BMC Biol ; 21(1): 231, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37867192

RESUMO

BACKGROUND: RNA splicing plays significant roles in fundamental biological activities. However, our knowledge about the roles of alternative splicing and underlying mechanisms during spermatogenesis is limited. RESULTS: Here, we report that Serine/arginine-rich splicing factor 2 (SRSF2), also known as SC35, plays critical roles in alternative splicing and male reproduction. Male germ cell-specific deletion of Srsf2 by Stra8-Cre caused complete infertility and defective spermatogenesis. Further analyses revealed that deletion of Srsf2 disrupted differentiation and meiosis initiation of spermatogonia. Mechanistically, by combining RNA-seq data with LACE-seq data, we showed that SRSF2 regulatory networks play critical roles in several major events including reproductive development, spermatogenesis, meiotic cell cycle, synapse organization, DNA recombination, chromosome segregation, and male sex differentiation. Furthermore, SRSF2 affected expression and alternative splicing of Stra8, Stag3 and Atr encoding critical factors for spermatogenesis in a direct manner. CONCLUSIONS: Taken together, our results demonstrate that SRSF2 has important functions in spermatogenesis and male fertility by regulating alternative splicing.


Assuntos
Splicing de RNA , Espermatogênese , Masculino , Humanos , Espermatogênese/genética , Proteínas de Ligação a RNA/genética , Processamento Alternativo , Meiose/genética , RNA Mensageiro
7.
Pediatr Surg Int ; 40(1): 38, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253735

RESUMO

PURPOSE: Hirschsprung's disease (HSCR) is the leading cause of neonatal functional intestinal obstruction, which has been identified in many familial cases. HSCR, a multifactorial disorder of enteric nervous system (ENS) development, is associated with at least 24 genes and seven chromosomal loci, with RET and EDNRB as its major genes. We present a genetic investigation of familial HSCR to clarify the genotype-phenotype relationship. METHODS: We performed whole exome sequencing (WES) on Illumina HiSeq X Ten platform to investigate genetic backgrounds of core family members, and identified the possibly harmful mutation genes. Mutation carriers and pedigree relatives were validated by Sanger sequencing for evaluating the gene penetrance. RESULTS: Four familial cases showed potential disease-relative variants in EDNRB and RET gene, accounting for all detection rate of 57.1%. Three familial cases exhibited strong pathogenic variants as frameshift or missense mutations in EDNRB gene. A novel c.367delinsTT mutation of EDNRB was identified in one family member. The other two EDNRB mutations, c.553G>A in family 2 and c.877delinsTT in family 5, have been reported in previous literatures. The penetrance of EDNRB variants was 33-50% according mutation carries. In family 6, the RET c.1858T>C (C620R) point mutation has previously been reported to cause HSCR, with 28.5% penetrance. CONCLUSION: We identified a novel EDNRB (deleted C and inserted TT) mutation in this study using WES. Heterozygote variations in EDNRB gene were significantly enriched in three families and RET mutations were identified in one family. EDNRB variants showed an overall higher incidence and penetrance than RET in southern Chinese families cases.


Assuntos
Doença de Hirschsprung , Obstrução Intestinal , Receptor de Endotelina B , Humanos , Recém-Nascido , China/epidemiologia , Doença de Hirschsprung/genética , Incidência , Mutação , Receptor de Endotelina B/genética
8.
J Cell Physiol ; 238(11): 2535-2545, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37642322

RESUMO

During the oocyte growth, maturation and zygote development, chromatin structure keeps changing to regulate different nuclear activities. Here, we reported the role of SMC2, a core component of condensin complex, in oocyte and embryo development. Oocyte-specific conditional knockout of SMC2 caused female infertility. In the absence of SMC2, oocyte meiotic maturation and ovulation occurred normally, but chromosome condensation showed defects and DNA damages were accumulated in oocytes. The pronuclei were abnormally organized and micronuclei were frequently observed in fertilized eggs, their activity was impaired, and embryo development was arrested at the one-cell stage, suggesting that maternal SMC2 is essential for embryonic development.


Assuntos
Núcleo Celular , Cromossomos , Animais , Feminino , Camundongos , Gravidez , Ciclo Celular , Núcleo Celular/fisiologia , Desenvolvimento Embrionário/genética , Meiose/genética , Oócitos/fisiologia , Zigoto
9.
Mol Med ; 29(1): 88, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37403020

RESUMO

BACKGROUND: Inflammation of the fetal membranes is an indispensable event of labor onset at both term and preterm birth. Interleukin-33 (IL-33) is known to participate in inflammation via ST2 (suppression of tumorigenicity 2) receptor as an inflammatory cytokine. However, it remains unknown whether IL-33/ST2 axis exists in human fetal membranes to promote inflammatory reactions in parturition. METHODS: The presence of IL-33 and ST2 and their changes at parturition were examined with transcriptomic sequencing, quantitative real-time polymerase chain reaction, Western blotting or immunohistochemistry in human amnion obtained from term and preterm birth with or without labor. Cultured primary human amnion fibroblasts were utilized to investigate the regulation and the role of IL-33/ST2 axis in the inflammation reactions. A mouse model was used to further study the role of IL-33 in parturition. RESULTS: Although IL-33 and ST2 expression were detected in both epithelial and fibroblast cells of human amnion, they are more abundant in amnion fibroblasts. Their abundance increased significantly in the amnion at both term and preterm birth with labor. Lipopolysaccharide, serum amyloid A1 and IL-1ß, the inflammatory mediators pertinent to labor onset, could all induce IL-33 expression through NF-κB activation in human amnion fibroblasts. In turn, via ST2 receptor, IL-33 induced the production of IL-1ß, IL-6 and PGE2 in human amnion fibroblasts via the MAPKs-NF-κB pathway. Moreover, IL-33 administration induced preterm birth in mice. CONCLUSION: IL-33/ST2 axis is present in human amnion fibroblasts, which is activated in both term and preterm labor. Activation of this axis leads to increased production of inflammatory factors pertinent to parturition, and results in preterm birth. Targeting the IL-33/ST2 axis may have potential value in the treatment of preterm birth.


Assuntos
Âmnio , Nascimento Prematuro , Animais , Feminino , Humanos , Recém-Nascido , Camundongos , Gravidez , Âmnio/metabolismo , Fibroblastos/metabolismo , Inflamação/metabolismo , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Interleucina-33 , NF-kappa B/metabolismo , Parto/metabolismo , Nascimento Prematuro/metabolismo
10.
Small ; 19(4): e2206155, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36437043

RESUMO

Atomic heating on single atoms (SAs) to maximize the catalytic efficiency of each active site would be a fascinating solution to break the bottleneck for the performance improvement of single-atom catalysts (SACs) but highly challenging task. Here, based on the Gd@MoS2 SACs synthesized by a facile laser molecular beam epitaxy method, high-frequency alternating magnetic field (AMF) technology is employed to induce atomic magnetic heating on Gd SAs that is meanwhile demonstrated to be the catalytic active center. Significant improvement in catalytic kinetics under AMF excitation (3.9 mT) is achieved, yielding a remarkable enhancement of hydrogen evolution reaction magnetothermal-current by ≈924%. Through theoretical calculations and spin-related electrochemical experiments, such promotion in catalyst activity can be attributed to spin flip (or canting) in Gd SAs leading to the atomic magnetic heating effect on catalytic active center. Together with the embodied high stability, the implement of AMF to the SAs field is demonstrated in this work, and the precisely atomic magnetic heating on specific SAs offers unprecedented thinking for further improvement of SACs performance in the future.

11.
Small ; 19(3): e2205665, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36404111

RESUMO

Although (oxy)hydroxides generated by electrochemical reconstruction (EC-reconstruction) of transition-metal catalysts exhibit highly catalytic activities, the amorphous nature fundamentally impedes the electrochemical kinetics due to its poor electrical conductivity. Here, EC-reconstructed NiFe/NiFeOOH core/shell nanoparticles in highly conductive carbon matrix based on the pulsed laser deposition prepared NiFe nanoparticles is successfully confined. Electrochemical characterizations and first-principles calculations demonstrate that the reconstructed NiFe/NiFeOOH core/shell nanoparticles exhibit high oxygen evolution reaction (OER) electrocatalytic activity (a low overpotential of 342.2 mV for 10 mA cm-2 ) and remarkable durability due to the efficient charge transfer in the highly conductive confined heterostructure. More importantly, benefit from the superparamagnetic nature of the reconstructed NiFe/NiFeOOH core/shell nanoparticles, a large OER improvement is achieved (an ultralow overpotential of 209.2 mV for 10 mA cm-2 ) with an alternating magnetic field stimulation. Such OER improvement can be attributed to the Néel relaxation related magnetic heating effect functionalized superparamagnetic NiFe cores, which are generally underutilized in reconstructed core/shell nanoparticles. This work demonstrates that the designed superparamagnetic core/shell nanoparticles, combined with the large improvement by magnetic heating effect, are expected to be highly efficient OER catalysts along with the confined structure guaranteed high conductivity and catalytic stability.

12.
Biol Reprod ; 108(3): 437-446, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36503987

RESUMO

As the most abundant organelles in oocytes, mitochondria play an important role in maintaining oocyte quality. Here, we report that March5, encoding a mitochondrial ubiquitin ligase that promotes mitochondrial elongation, plays a critical role in mouse oocyte meiotic maturation via regulating mitochondrial function. The subcellular localization of MARCH5 was similar to the mitochondrial distribution during mouse oocyte meiotic progression. Knockdown of March5 caused decreased ratios of the first polar body extrusion. March5-siRNA injection resulted in oocyte mitochondrial dysfunctions, manifested by increased reactive oxygen species, decreased ATP content as well as decreased mitochondrial membrane potential, leading to reduced ability of spindle formation and an increased ratio of kinetochore-microtubule detachment. Further study showed that the continuous activation of the spindle assembly checkpoint and the failure of Cyclin B1 degradation caused MI arrest and first polar body (PB1) extrusion failure in March5 knockdown oocytes. Taken together, our results demonstrated that March5 plays an essential role in mouse oocyte meiotic maturation, possibly via regulation of mitochondrial function and/or ubiquitination of microtubule dynamics- or cell cycle-regulating proteins.


Assuntos
Oogênese , Ubiquitina-Proteína Ligases , Animais , Camundongos , Mitocôndrias/metabolismo , Oócitos/metabolismo , Proteínas/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
13.
Synapse ; 77(4): e22270, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37122072

RESUMO

Epilepsy is a common chronic neurological disorder characterized by widespread neuronal death. The purpose of this study was to investigate the role of nuclear factor erythroid 2-related factor 2 (Nrf2) m6A methylation in epilepsy. To create epileptic models, the rats were given Lithium chloride and pilocarpine, and isolated primary rat hippocampal neurons were cultured in an Mg2+ -free medium. The frequency of seizures was recorded in the epilepsy group of rats. The functional tests included TUNEL, MTT, and flow cytometry. Mechanistically, RNA degradation assay, RNA immunoprecipitation, and methylated RNA immunoprecipitation were performed. In epileptic models, Nrf2 and fat mass and obesity-associated (FTO) levels were downregulated, whereas YT521-B homology (YTH) domain family protein 2 (YTHDF2) was upregulated. Additionally, in epileptic models, there was a rise in the m6A methylation level of Nrf2 mRNA. Overexpressing FTO increased cell viability and reduced apoptosis, but Nrf2 interference reversed these effects. Meanwhile, FTO overexpression decreased the m6A methylation of Nrf2 mRNA. Moreover, YTHDF2 bound to Nrf2 mRNA and decreased its stability. Furthermore, FTO overexpression reduced seizure frequency in rats and inhibited hippocampal neuron apoptosis via lowering the m6A methylation level of Nrf2 mRNA. Overexpressing FTO reduced m6A methylation of Nrf2 mRNA, increased cell viability, suppressed apoptosis, and slowed the progression of epileptic diseases, which is linked to YTHDF2 binding to m6A-modified Nrf2 and promoting its degradation, as well as downregulating Nrf2 expression in hippocampal neurons.


Assuntos
Epilepsia , Fator 2 Relacionado a NF-E2 , Ratos , Animais , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Regulação para Baixo , Epilepsia/metabolismo , RNA/efeitos adversos , RNA/metabolismo , RNA Mensageiro/metabolismo , Convulsões/metabolismo , Neurônios/metabolismo , Hipocampo/metabolismo
14.
Inflamm Res ; 72(4): 797-812, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36879064

RESUMO

OBJECTIVES: Sterile inflammation of fetal membranes is an indispensable event of normal parturition. However, triggers of sterile inflammation are not fully resolved. Serum amyloid A1 (SAA1) is an acute phase protein produced primarily by the liver. Fetal membranes can also synthesize SAA1 but its functions are not well defined. Given the role of SAA1 in the acute phase response to inflammation, we postulated that SAA1 synthesized in the fetal membranes may be a trigger of local inflammation at parturition. METHODS: The changes of SAA1 abundance in parturition were studied in the amnion of human fetal membranes. The role of SAA1 in chemokine expression and leukocyte chemotaxis was examined in cultured human amnion tissue explants as well as primary human amnion fibroblasts. The effects of SAA1 on monocytes, macrophages and dendritic cells were investigated in cells derived from a human leukemia monocytic cell line (THP-1). RESULTS: SAA1 synthesis increased significantly in human amnion at parturition. SAA1 evoked multiple chemotaxis pathways in human amnion fibroblasts along with upregulation of a series of chemokines via both toll-like receptor 4 (TLR4) and formyl peptide receptor 2 (FPR2). Moreover, SAA1-conditioned medium of cultured amnion fibroblasts was capable of chemoattracting virtually all types of mononuclear leukocytes, particularly monocytes and dendritic cells, which reconciled with the chemotactic activity of conditioned medium of cultured amnion tissue explants collected from spontaneous labor. Furthermore, SAA1 could induce the expression of genes associated with inflammation and extracellular matrix remodeling in monocytes, macrophages and dendritic cells derived from THP-1. CONCLUSIONS: SAA1 is a trigger of sterile inflammation of the fetal membranes at parturition.


Assuntos
Âmnio , Parto , Gravidez , Feminino , Humanos , Âmnio/metabolismo , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Parto/genética , Parto/metabolismo , Membranas Extraembrionárias/metabolismo , Quimiocinas/metabolismo , Inflamação/metabolismo , Proteína Amiloide A Sérica
15.
Phys Chem Chem Phys ; 25(16): 11827-11838, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37067819

RESUMO

Two-dimensional (2D) layered palladium dichalcogenides PdX2 (X = S and Se) have attracted increasing interest due to their tunable electronic structure and abundant physicochemical properties. Recently, as the sister material of PdX2, PdSSe has received increasing attention and shows great promise for technological applications and fundamental research. In the present study, we focus on the layer-dependent geometry, electronic structure, and optical properties of PdSSe using first-principles calculations. The lattice shrinkage effect present in the 2D structure is suppressed with increasing number of layers. Attributed to the strong interlayer coupling interactions, the band gap decreases from 2.30 to 0.83 eV with increased thickness. Particularly, the dispersion of the band edges on the high symmetry path changes considerably from the monolayer to bilayer PdSSe, resulting in shifts of the conduction band minimum and valence band maximum. The multilayer PdSSe shows band convergence feature with multi-valley for the conduction band, which are maintained with reduced effective mass. Furthermore, the increasing number of layers drives a wider absorption range in the visible light region, and the light absorption capability increases from ∼10% to ∼30%. Meanwhile, the band edge positions of the multilayer PdSSe are more appropriate for photocatalytic water splitting. Our theoretical study reveals the enhanced valley convergence, conductivity and optical absorption performance of the few-layer PdSSe, which suggests its promising application in thermoelectric conversion, solar harvesting and photocatalysis.

16.
Phys Chem Chem Phys ; 25(43): 30066-30078, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37906277

RESUMO

Due to their unique structure, abundant properties and potential applications, low-dimensional materials with covalently bonded building blocks through van der Waals (vdW) interactions have sparked widespread interest. Recently, the bulk phase NbS4 consisting of one-dimensional (1D) chains has been synthesized successfully, adding a new member to the group V metallic polychalcogenide family. In the present study, based on density functional theory calculations, we obtained a better understanding of the stability, mechanical properties, electronic structures, transport properties and optical performances of the bulk phase NbS4. Furthermore, the possibility of exfoliating 1D single-chain nanowires from the bulk phase was uncovered. Both bulk phase and 1D nanowires show dynamic, thermal, and mechanical stabilities. The bulk phase possesses an indirect band gap of 1.39 eV with high anisotropic carrier mobilities of 471.814 cm2 s-1 v-1 for electrons (along the b axis direction) and 546.92 cm2 s-1 v-1 for holes (along the a axis direction). The single-chain nanowire exhibits remarkable flexibility and can resist 24% tensile strain along the chain direction. The decreased dimension from the bulk phase to the individual 1D chain not only makes the band gap increase to 1.81 eV but also results in an indirect-to-direct band gap transition, indicating a strong quantum confinement effect. The 1D single-chain nanowire also shows high carrier mobilities of 111.91 cm2 s-1 v-1 for electrons and 316.63 cm2 s-1 v-1 for holes along the chain direction. In addition, both bulk phase and 1D nanowire display excellent visible light absorption performance along the chain direction and the absorption coefficients reach the order of 106 and 105 cm-1. These promising properties render quasi 1D NbS4 as candidate materials for nanoscale applications in high-performance optoelectronic and nanoelectronic devices. The predicted unconventional properties of NbS4 not only provide a meaningful complement to the fascinating quasi 1D material family, but also will attract extensive interest from a wide audience to explore unanticipated properties and design new nanoscale devices based on NbS4.

17.
Exp Cell Res ; 416(1): 113135, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35398309

RESUMO

Microtubule plus-end tracking proteins (+TIPs) associate with growing microtubule plus ends and control microtubule dynamics and interactions with different cellular structures during cell division, cell migration and morphogenesis. Microtubule-associated RP/EB family member 2 (MAPRE2/EB2) is a highly conserved core component of +TIPs networks, but whether this molecule is required for mammalian meiotic progression is unknown. In this study, we investigated the expression and function of MAPRE2 during oocyte maturation. Our results showed that MAPRE2 was consistently expressed from germinal vesicle (GV) to metaphase II (MII) stages and that MAPRE2 was distributed in the cytoplasm of oocytes at GV stage and along the spindle at metaphase I (MI) and MII stages. Small interfering RNA-mediated knockdown of Mapre2 severely impaired microtubule stability, kinetochore-microtubule attachment, and chromosome alignment and subsequently caused spindle assembly checkpoint (SAC) activation and cyclin B1 nondegradation, leading to failure of chromosome segregation and first polar body extrusion. This study demonstrates for the first time that MAPRE2 plays an important role during mouse oocyte meiosis.


Assuntos
Meiose , Fuso Acromático , Animais , Segregação de Cromossomos , Mamíferos , Metáfase , Camundongos , Oócitos/metabolismo , Fuso Acromático/metabolismo
18.
Nano Lett ; 22(23): 9411-9417, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36410739

RESUMO

Alternating magnetic field (AMF) is a promising methodology for further improving magnetic single-atom catalyst (SAC) activity toward oxygen evolution reaction (OER). Herein, the anchoring of Co single atoms on MoS2 support (Co@MoS2), leading to the appearance of in-plane room-temperature ferromagnetic properties, is favorable for the parallel spin arrangement of oxygen atoms when a magnetic field is applied. Moreover, field-assisted electrocatalytic experiments confirmed that the spin direction of Co@MoS2 is changing with the applied magnetic field. On this basis, under AMF, the active sites in ferromagnetic Co@MoS2 were heated by exploiting the magnetic heating generated from spin polarization flip of these SACs to further expedite OER efficiency, with overpotential at 10 mA cm-2 reduced from 317 mV to 250 mV. This work introduces a feasible and efficient approach to enhance the OER performance of Co@MoS2 by AMF, shedding some light on the further development of magnetic SACs for energy conversion.

19.
Int J Mol Sci ; 24(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446059

RESUMO

Inflammation of the fetal membranes is an indispensable event of parturition, with increasing prostaglandin E2 (PGE2) synthesis as one of the ultimate products that prime labor onset. In addition to PGE2, the fetal membranes also boast a large capacity for cortisol regeneration. It is intriguing how increased PGE2 synthesis is achieved in the presence of increasing amounts of classical anti-inflammatory glucocorticoids in the fetal membranes at parturition. 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE) synthesized by lipoxygenase 15/15B (ALOX15/15B) has been shown to enhance inflammation-induced PGE2 synthesis in amnion fibroblasts. Here, we examined whether glucocorticoids could induce ALOX15/15B expression and 15(S)-HETE production to promote PGE2 synthesis in amnion fibroblasts at parturition. We found that cortisol and 15(S)-HETE abundance increased parallelly in the amnion at parturition. Cortisol induced ALOX15/15B expression and 15(S)-HETE production paradoxically in amnion fibroblasts. Mechanism study revealed that this paradoxical induction was mediated by p300-mediated histone acetylation and interaction of glucocorticoid receptor with transcription factors CREB and STAT3. Conclusively, cortisol regenerated in the fetal membranes can paradoxically induce ALOX15/15B expression and 15(S)-HETE production in human amnion fibroblasts, which may further assist in the induction of PGE2 synthesis in the inflammatory responses of the fetal membranes for parturition.


Assuntos
Âmnio , Hidrocortisona , Gravidez , Feminino , Humanos , Hidrocortisona/metabolismo , Âmnio/metabolismo , Glucocorticoides/metabolismo , Dinoprostona/metabolismo , Parto , Membranas Extraembrionárias/metabolismo , Fibroblastos/metabolismo , Inflamação/metabolismo , Araquidonato 15-Lipoxigenase/metabolismo
20.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38203660

RESUMO

Jasmine, a recently domesticated shrub, is renowned for its use as a key ingredient in floral tea and its captivating fragrance, showcasing significant ornamental and economic value. When cultivated to subtropical zone, a significant abiotic stress adaptability occurs among different jasmine varieties, leading to huge flower production changes and plantlet survival. The bZIP transcription factors (TFs) are reported to play indispensable roles in abiotic stress tolerance. Here, we performed a genome-level comparison of bZIPs using three-type jasmine genomes. Based on their physicochemical properties, conserved motif analysis and phylogenetic analysis, about 63 bZIP genes were identified and clustered in jasmine genomes, noting a difference of one member compared to the other two types of jasmines. The HTbZIP genes were categorized into 12 subfamilies compared with A. thaliana. In cis-acting element analysis, all genes contained light-responsive elements. The abscisic acid response element (ABRE) was the most abundant in HTbZIP62 promoter, followed by HTbZIP33. Tissue-specific genes of the bZIPs may play a crucial role in regulating the development of jasmine organs and tissues, with HTbZIP36 showing the most significant expressions in roots. Combined with complicated protein interactions, HTbZIP62 and HTbZIP33 might play a crucial role in the ABA signaling pathway and stress tolerance. Combined with RT-qPCR analysis, SJbZIP37/57/62 were more sensitive to ABA response genes compared with other bZIPs in DJ amd HT genomes. Our findings provide a useful resource for further research on the regulation of key genes to improve abiotic stress tolerance in jasmine.


Assuntos
Adaptação Fisiológica , Jasminum , Ácido Abscísico/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Jasminum/genética , Jasminum/metabolismo , Filogenia , Estresse Fisiológico , Adaptação Fisiológica/genética
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