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1.
J Biol Chem ; 298(8): 102180, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35752363

RESUMO

The integrated stress response is a network of highly orchestrated pathways activated when cells are exposed to environmental stressors. While global repression of translation is a well-recognized hallmark of the integrated stress response, less is known about the regulation of mRNA stability during stress. DEAD box proteins are a family of RNA unwinding/remodeling enzymes involved in every aspect of RNA metabolism. We previously showed that DEAD box 1 (DDX1) protein accumulates at DNA double-strand breaks during genotoxic stress and promotes DNA double-strand break repair via homologous recombination. Here, we examine the role of DDX1 in response to environmental stress. We show that DDX1 is recruited to stress granules (SGs) in cells exposed to a variety of environmental stressors, including arsenite, hydrogen peroxide, and thapsigargin. We also show that DDX1 depletion delays resolution of arsenite-induced SGs. Using RNA immunoprecipitation sequencing, we identify RNA targets bound to endogenous DDX1, including RNAs transcribed from genes previously implicated in stress responses. We show the amount of target RNAs bound to DDX1 increases when cells are exposed to stress, and the overall levels of these RNAs are increased during stress in a DDX1-dependent manner. Even though DDX1's RNA-binding property is critical for maintenance of its target mRNA levels, we found RNA binding is not required for localization of DDX1 to SGs. Furthermore, DDX1 knockdown does not appear to affect RNA localization to SGs. Taken together, our results reveal a novel role for DDX1 in maintaining cytoplasmic mRNA levels in cells exposed to oxidative stress.


Assuntos
Arsenitos , RNA Helicases DEAD-box , Arsenitos/toxicidade , RNA Helicases DEAD-box/metabolismo , DNA/metabolismo , Estresse Oxidativo , RNA/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
Appl Environ Microbiol ; 89(4): e0001523, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-36920190

RESUMO

Compartmentalization of macromolecules into discrete non-lipid-bound bodies by liquid-liquid phase separation (LLPS) is a well-characterized regulatory mechanism frequently associated with the cellular stress response in eukaryotes. In contrast, the formation and importance of similar complexes is just becoming evident in bacteria. Here, we identify LLPS as the mechanism by which the DEAD-box RNA helicase, cyanobacterial RNA helicase redox (CrhR), compartmentalizes into dynamic membraneless organelles in a temporal and spatial manner in response to abiotic stress in the cyanobacterium Synechocystis sp. strain PCC 6803. Stress conditions induced CrhR to form a single crescent localized exterior to the thylakoid membrane, indicating that this region is a crucial domain in the cyanobacterial stress response. These crescents rapidly dissipate upon alleviation of the stress conditions. Furthermore, CrhR aggregation was mediated by LLPS in an RNA-dependent reaction. We propose that dynamic CrhR condensation performs crucial roles in RNA metabolism, enabling rapid adaptation of the photosynthetic apparatus to environmental stresses. These results expand our understanding of the role that functional compartmentalization of RNA helicases and thus RNA processing in membraneless organelles by LLPS-mediated protein condensation performs in the bacterial response to environmental stress. IMPORTANCE Oxygen-evolving photosynthetic cyanobacteria evolved ~3 billion years ago, performing fundamental roles in the biogeochemical evolution of the early Earth and continue to perform fundamental roles in nutrient cycling and primary productivity today. The phylum consists of diverse species that flourish in heterogeneous environments. A prime driver for survival is the ability to alter photosynthetic performance in response to the shifting environmental conditions these organisms continuously encounter. This study demonstrated that diverse abiotic stresses elicit dramatic changes in localization and structural organization of the RNA helicase CrhR associated with the photosynthetic thylakoid membrane. These dynamic changes, mediated by a liquid-liquid phase separation (LLPS)-mediated mechanism, reveal a novel mechanism by which cyanobacteria can compartmentalize the activity of ribonucleoprotein complexes in membraneless organelles. The results have significant consequences for understanding bacterial adaptation and survival in response to changing environmental conditions.


Assuntos
Synechocystis , Synechocystis/genética , Synechocystis/metabolismo , Condensados Biomoleculares , Oxirredução , RNA Helicases DEAD-box/metabolismo , RNA/metabolismo , Organelas/metabolismo
3.
Scand J Clin Lab Invest ; 83(2): 103-110, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36811410

RESUMO

Cell division cycle 42 (CDC42) regulates the development of colorectal cancer (CRC) by modulating cancer malignant behaviors and facilitating immune escape. Hence, this study aimed to explore the correlation of blood CDC42 with treatment response and survival benefit to programmed cell death-1 (PD-1) inhibitor-based regimens in inoperable metastatic CRC (mCRC) patients. Fifty-seven inoperable mCRC patients who received PD-1 inhibitor-based regimens were recruited. The CDC42 in peripheral blood mononuclear cell (PBMC) was detected using RT-qPCR in inoperable mCRC patients at baseline and after 2-cycle treatment. Besides, PBMC CDC42 in 20 healthy controls (HCs) was also detected. CDC42 was higher in inoperable mCRC patients compared to HCs (p < 0.001). Elevated CDC42 was related to a higher performance status score (p = 0.034), multiple metastatic sites (p = 0.028), and the presence of liver metastasis (p = 0.035) in inoperable mCRC patients. During the 2-cycle treatment, CDC42 was reduced (p < 0.001). Higher CDC42 at baseline (p = 0.016) and after 2-cycle treatment (p = 0.002) were both linked with decreased objective response rate. CDC42 high at baseline was related to shorter progression-free survival (PFS) (p = 0.015) and overall survival (OS) (p = 0.050). Moreover, CDC42 high after 2-cycle treatment was also related to unfavorable PFS (p < 0.001) and OS (p = 0.001). After adjustment using multivariate Cox's analyses, CDC42 high after 2-cycle treatment independently related to shorter PFS (hazard ratio (HR): 4.129, p < 0.001), and CDC42 reduction ≤230% also independently correlated with shorter OS (HR: 4.038, p < 0.001). The longitudinal change of blood CDC42 during PD-1 inhibitor-based regimen estimates treatment response and survival in inoperable mCRC patients.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Inibidores de Checkpoint Imunológico , Leucócitos Mononucleares , Intervalo Livre de Doença , Ciclo Celular
4.
Int J Mol Sci ; 24(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36834852

RESUMO

Plant epistatic regulation is the DNA methylation, non-coding RNA regulation, and histone modification of gene sequences without altering the genome sequence, thus regulating gene expression patterns and the growth process of plants to produce heritable changes. Epistatic regulation in plants can regulate plant responses to different environmental stresses, regulate fruit growth and development, etc. Genome editing can effectively improve plant genetic efficiency by targeting the design and efficient editing of genome-specific loci with specific nucleases, such as zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALEN), and clustered regularly interspaced short palindromic repeats/CRISPR-associated 9 (CRISPR/Cas9). As research progresses, the CRISPR/Cas9 system has been widely used in crop breeding, gene expression, and epistatic modification due to its high editing efficiency and rapid translation of results. In this review, we summarize the recent progress of CRISPR/Cas9 in epigenome editing and look forward to the future development direction of this system in plant epigenetic modification to provide a reference for the application of CRISPR/Cas9 in genome editing.


Assuntos
Sistemas CRISPR-Cas , Epigenoma , Genoma de Planta , Melhoramento Vegetal/métodos , Plantas/genética , Edição de Genes/métodos
5.
Arch Orthop Trauma Surg ; 143(8): 5239-5248, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36971801

RESUMO

INTRODUCTION: The results of revision total knee arthroplasty (rTKA) may be compromised by excessive joint line (JL) elevation. It is critical but challenging in reestablishing the JL in rTKA. Previous studies have confirmed that, biomechanically and clinically, JL elevation should not exceed 4 mm. Image-based studies described several approaches to locate the JL intraoperatively, however magnification errors could occur. In this cadaveric study, we aim to define an accurate and reliable method to determine the JL. MATERIALS AND METHODS: Thirteen male and eleven female cadavers were used, with an average age of death being 48.3 years. The transepicondylar width (TEW), the distance from the medial (MEJL) and lateral (LEJL) epicondyle, adductor tubercle (ATJL), fibular head (FHJL) and tibial tubercle (TTJL) to the JL were measured in 48 knees. Intra- and interobserver reliability and validity were tested prior to any additional analysis. Pearson correlation and linear regression analysis were used to examine the correlations between landmark-JL distances (LEJL, MEJL, ATJL, FHJL and TTJL) and the TEW, and to further derive models for intraoperative JL determination. The accuracy of different models, quantified by errors between estimated and measured landmark-JL distances, was compared using the Friedman and post hoc Dunn tests. RESULTS: The intra- and inter-observer measurements for TEW, MEJL, LEJL, ATJL, TTJL and FHJL did not differ significantly (p > 0.05). Between genders, significant differences were found on TEW, MEJL, LEJL, ATJL, FHJL and TTJL (p < 0.05). There was no association between TEW and either FHJL or TTJL (p > 0.05), while ATJL, MEJL, and LEJL were found to be correlated with TEW (p < 0.05). Six models were derived: (1) MEJL = 0.37*TEW (r = 0.384), (2) LEJL = 0.28*TEW (r = 0.380), (3) ATJL = 0.47*TEW (r = 0.608), (4) MEJL = 0.413*TEW - 4.197 (R2 = 0.473), (5) LEJL = 0.236*TEW + 3.373 (R2 = 0.326), (6) ATJL = 0.455*TEW + 1.440 (R2 = 0.556). Errors were defined as deviations between estimated and actual landmark-JL distances. The mean absolute value of the errors, created by Model 1-6 was 3.18 ± 2.25, 2.53 ± 2.15, 2.64 ± 2.2, 1.85 ± 1.61, 1.60 ± 1.59 and 1.71 ± 1.5, respectively. The error could be limited to 4 mm in 72.9%, 83.3%, 72.9%, 87.5%, 87.5%, and 93.8% of the cases by referencing Model 1-6, respectively. CONCLUSION: Compared to previous image-based measurements, the current cadaveric study most closely resembles a realistic view of intraoperative settings and could circumvents magnification errors. We recommend using Model 6, the JL can be best estimated by referencing the AT and the ATJL can be calculated as ATJL (mm) = 0.455*TEW (mm) + 1.440 (mm).


Assuntos
Artroplastia do Joelho , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Artroplastia do Joelho/métodos , Articulação do Joelho/cirurgia , Modelos Lineares , Reprodutibilidade dos Testes , Tíbia/cirurgia , Cadáver
6.
Environ Toxicol ; 37(12): 2965-2976, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36029293

RESUMO

Perfluorooctanoic acid (PFOA), a member of a group of polyfluorinated and perfluorinated alkyl substances (PFAS), is associated with adverse pregnancy outcomes in mammals. However, the effects of in vivo exposure to PFOA on the female reproductive system and the underlying mechanisms remain unclear. In our study, we constructed a mouse model to investigate whether low-dose PFOA (1 mg/kg/day) or high-dose PFOA (5 mg/kg/day) affect meiosis maturation of oocytes and the potential mechanisms that may be associated with oocyte maturation disorder. Our results indicate that low-dose and high-dose PFOA can lead to impaired oocyte maturation, which is manifested by decreased rate of embryonic foam rupture and first polar body extrusion. Moreover, PFOA exposure harmed the mitochondrial metabolic, resulting in low levels of ATP contents, high reactive oxygen species, aberrant mitochondrial membrane potential. In addition, the proportion of DNA damage marker γ-H2AX was also significantly increased in PFOA exposure oocytes. These changes lead to abnormal arrangements of the spindle and chromosomes during oocyte maturation. In conclusion, our results for the first time illustrated that exposure to PFOA in vivo in female mice impaired the meiosis maturation of oocytes, which provided a basis for studying the mechanism of PFOA reproductive toxicity in female mammals.


Assuntos
Fluorocarbonos , Gravidez , Feminino , Camundongos , Animais , Fluorocarbonos/metabolismo , Oogênese , Oócitos , Caprilatos/metabolismo , Meiose , Mamíferos
7.
Nano Lett ; 21(14): 6220-6227, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34264683

RESUMO

Plasmonic nanostructures can enable compact multiplexing of the orbital angular momentum (OAM) of light; however, strong dissipation of the highly localized OAM-distinct plasmonic fields in the near-field region hinders on-chip OAM transmission and processing. Superior transmission efficiency is offered by semiconductor nanowires sustaining highly confined optical modes, but only the polarization degree of freedom has been utilized for their selective excitation. Here we demonstrate that incident OAM beams can selectively excite single-crystalline cadmium sulfide (CdS) nanowires through coupling OAM-distinct plasmonic fields into nanowire waveguides for long-distance transportation. This allows us to build an OAM-controlled hybrid nanowire circuit for optical logic operations including AND and OR gates. In addition, this circuit enables the on-chip photoluminescence readout of OAM-encrypted information. Our results open exciting new avenues not only for nanowire photonics to develop OAM-controlled optical switches, logic gates, and modulators but also for OAM photonics to build ultracompact photonic circuits for information processing.

8.
Dev Biol ; 455(2): 420-433, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31330130

RESUMO

Temporally-regulated maternal RNA translation is essential for embryonic development, with defective degradation resulting in stalled 2-cell embryos. We show that DDX1, a DEAD box protein implicated in RNA transport, may be a key regulator of maternal RNA utilization. DDX1 protein localizes exclusively to cytoplasmic granules in both oocytes and early stage mouse embryos, with DDX1 requiring RNA for retention at these sites. Homozygous knockout of Ddx1 causes stalling of mouse embryos at the 2-4 cell stages. These results suggest a maternal RNA-dependent role for DDX1 in the progression of embryos past the 2-4 cell stage. The change in appearance of DDX1-containing granules in developing embryos further supports a role in temporally-regulated degradation of RNAs. We carried out RNA-immunoprecipitations (RNA-IPs) to identify mRNAs bound to DDX1 in 2-cell embryos, focusing on 16 maternal genes previously shown to be essential for embryonic development past the 1- to 2-cell stages. Five of these RNAs were preferentially bound by DDX1: Ago2, Zar1, Tle6, Floped and Tif1α. We propose that DDX1 controls access to subsets of key maternal RNAs required for early embryonic development.


Assuntos
RNA Helicases DEAD-box/metabolismo , Desenvolvimento Embrionário/fisiologia , Animais , Grânulos Citoplasmáticos/metabolismo , RNA Helicases DEAD-box/genética , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ovário , RNA/metabolismo , Estabilidade de RNA , Proteínas de Ligação a RNA/metabolismo , Técnicas de Cultura de Tecidos
9.
Cell Physiol Biochem ; 34(3): 628-36, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25171776

RESUMO

BACKGROUND/AIMS: The invasion of trophoblast cells into the maternal uterine decidua is critical for normal placentation, establishment of pregnancy and maintenance of fetal growth in humans. Several growth factors and cytokines have been implicated in trophoblast invasion, but the underlying regulatory mechanisms of invasion are not fully understood. Our earlier studies have found that caudal-related homeobox transcription factor 2 (CDX2) is hypomethylated in human pre-eclampsia placental tissues. However, whether CDX2 is involved in trophoblast invasion was unclear. METHODS AND RESULTS: In this study, we investigated CDX2 function using a human HTR-8/SVneo cell line that overexpressed CDX2. Cell invasion assays demonstrated that CDX2 enhanced trophoblast cell invasiveness. Meanwhile, MTT assays revealed that CDX2 did not affect cell proliferation. Western blot analysis and quantitative real-time PCR demonstrated that the expression level of matrix metalloproteinase-9 (MMP-9) was significantly increased, whereas the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) was markedly suppressed in the CDX2-overexpressing trophoblast cells. The phosphoinositide-3-kinase (PI3K)/Akt signaling pathway is involved in proliferation, migration, metastasis and invasion. Our study showed that inhibition of PI3K/Akt signaling led to decreased expression of CDX2. CONCLUSION: We concluded that CDX2 is likely regulated by the PI3K/Akt signaling pathway during trophoblast cell invasion. Our findings may reveal new insights into the regulatory mechanisms of trophoblast cell invasion and may be an important contributor to the pathogenesis of pregnancy-related diseases.


Assuntos
Proteínas de Homeodomínio/fisiologia , Metaloproteinases da Matriz/metabolismo , Trofoblastos/citologia , Sequência de Bases , Western Blotting , Fator de Transcrição CDX2 , Linhagem Celular , Primers do DNA , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Trofoblastos/enzimologia
10.
Front Surg ; 11: 1279462, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38919978

RESUMO

Background: Total knee arthroplasty (TKA) is a common and effective procedure. Optimizing pain control and reducing postoperative discomfort are essential for patient satisfaction. No studies have examined the safety and efficacy of intra-articular corticosteroid injections following TKA. This study aims to examine the safety and efficacy of corticosteroids in intra-articular multimodal analgesic injections. Materials and methods: This was a historically controlled study conducted at a single academic institution. Before May 2019, patients received an intra-articular cocktail injection without corticosteroids during surgery, referred to as the non-corticosteroid (NC) group. After June 2019, intraoperatively, patients received an intra-articular cocktail injection containing corticosteroids, referred to as the corticosteroid (C) group. Finally, 738 patients were evaluated, 370 in the C cohort and 368 in the NC cohort. The mean follow-up duration was 30.4 months for the C group and 48.4 months for the NC group. Results: The mean VAS scores at rest on postoperative day (POD) 1 (2.35) and POD3 (3.88) were significantly lower in the C group than those in the NC group, which were 2.86 (POD1) and 5.26 (POD3) (p < 0.05). Walking pain in the C group (4.42) was also significantly lower than that (5.96) in the NC group on POD3 (p < 0.05). Patients in the C group had a significantly higher mean range of motion (ROM) (92.55) on POD3 than that (86.38) in the NC group. The mean time to straight leg raise for group C (2.77) was significantly shorter than that (3.61) for the NC group (p < 0.05). The C group also had significantly fewer rescue morphine (1.9) and metoclopramide (0.21) uses per patient than the NC group, which were 3.1 and 0.24, respectively. No significant differences in fever or vomiting rates between groups were found. Patients in neither group developed periprosthetic joint infections or skin necrosis. One patient in the C group suffered from wound dehiscence, and the wound healed well after debridement. No patient died or had a re-operation in either group. Conclusions: This pilot trial found that intra-articular injection of multimodal analgesia (including corticosteroids) reduced initial postoperative pain, increased ROM in the early postoperative days (up to POD3), and did not increase wound complications or infection rates in approximately 30 months of follow-up.

11.
Plants (Basel) ; 13(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38794398

RESUMO

Exogenous selenium application could effectively improve the selenium absorption of crops affected by different climatic conditions due to changes in the planting environment and planting conditions. We planted maize at planting densities of 67,500 plants ha-1 (D1) and 75,000 plants ha-1 (D2). Five selenium fertilizer gradients of 0 mg m-2 (Se0), 7.5 mg m-2 (Se1), 15.0 mg m-2 (Se2), 22.5 mg m-2 (Se3), and 30.0 mg m-2 (Se4) were applied to investigate the response of the plants to selenium fertilizer application in terms of the gradient selenium absorption and substance accumulation. With the increase in the amount of selenium fertilizer applied, more of the selenium fertilizer will be absorbed and transported from the leaves to the grains, and the selenium content of the grains will gradually increase and exceed the selenium content of leaves. Under the D2 density in 2022, the selenium content of the grains under Se1, Se2, Se3, and Se4 treatments increased by 65.67%, 72.71%, and 250.53%, respectively, compared with that of Se0. A total of 260.55% of the plants showed a gradient of grain > leaf > cob > stalk from the Se2 treatment, and the overall selenium content of the plants increased first and then decreased. Under the D1 density, compared with the Se0, the dry matter mass of the Se1, Se2, Se3, and Se4 treatments significantly improved by 5.84%, 1.49%, and 14.26% in 2021, and significantly improved by 4.84%, 3.50%, and 2.85% in 2022. The 1000-grain weight under Se2, Se3, and Se4 treatments improved by 8.57%, 9.06%, and 15.56% compared to that under the Se0 treatment, and the yield per ha under the Se2, Se3, and Se4 treatments was 18.58%, 9.09%, and 21.42% higher than that under Se0 treatment, respectively. In addition, a reasonable combination of selenium application rate and density could improve the chlorophyll content and stem growth of dryland maize. This lays a foundation for the efficient application of selenium fertilizer and provides an important reference.

12.
Taiwan J Obstet Gynecol ; 63(3): 307-311, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38802192

RESUMO

Trace metals play a vital role in a variety of biological processes, but excessive amounts can be toxic and are receiving increasing attention. Trace metals in the environment are released from natural sources, such as rock weathering, volcanic eruptions, and other human activities, such as industrial emissions, mineral extraction, and vehicle exhaust. Lifestyle, dietary habits and environmental quality are the main sources of human exposure to trace metals, which play an important role in inducing human reproductive infertility. The purpose of this review is to summarize the distribution of various trace metals in oocyte and to identify the trace metals that may cause oocyte used in the design and execution of toxicological studies.


Assuntos
Oócitos , Oligoelementos , Humanos , Oócitos/efeitos dos fármacos , Oligoelementos/análise , Oligoelementos/efeitos adversos , Feminino , Exposição Ambiental/efeitos adversos , Metais Pesados/análise , Metais/efeitos adversos , Metais/análise
13.
J Cloud Comput (Heidelb) ; 12(1): 18, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36789367

RESUMO

According to the connotation and structure of government service resources, data of government service resources in L city from 2019 to 2021 are used to calculate the efficiency of government service resource allocation in each county and region in different periods, particularly by adding the government cloud platform and cloud computing resources to the government service resource data and applying the data envelopment analysis (DEA) method, which has practical significance for the development and innovation of government services. On this basis, patterns and evolutionary trends of government service resource allocation efficiency in each region during the study period are analyzed and discussed. Results are as follows. i) Overall efficiency level in the allocation of government service resources in L city is not high, showing an increasing annual trend among the high and low staggering. ii) Relative difference of allocation efficiency of government service resources is a common phenomenon of regional development, the existence and evolution of which are the direct or indirect influence and reflection of various aspects, such as economic strength and reform effort. iii) Data analysis for the specific points indicates that increased input does not necessarily lead to increased efficiency, some indicators have insufficient input or redundant output. Therefore, optimization of the physical, human, and financial resource allocation methods; and the intelligent online processing of government services achieved by the adoption of government cloud platform and cloud computing resources are the current objective choices to realize maximum efficiency in the allocation of government service resources.

14.
RSC Adv ; 13(9): 5893-5899, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36816078

RESUMO

Two-dimensional layered (BA)2PbI4 (BA = C4H9NH3) perovskites are emerging as a new class of layered materials and show great potential in optoelectronic applications. Elucidating how exciton-phonon interaction affects the excitonic emission is of great importance for a better knowledge of their optoelectronic properties. In this letter, we synthesized high-quality (BA)2PbI4 microplates via solution methods, and dual-excitonic emission peaks (surface-emission and interior-emission) were detected from the as-grown samples at low temperatures. Furthermore, we determine the energies for the longitudinal optical phonon modes to be ∼27 and ∼18 meV, and the exciton-phonon coupling strengths to be ∼177 and ∼21 meV for the surface-emission and interior-emission bands, respectively. Compared to the interior-emission band, the stronger exciton-phonon interaction results in a considerable degree of spectral broadening and red-shift for the surface-emission with increasing temperature. In contrast, the (OA)2PbI4 (OA = C8H17NH2) microplates with longer alkyl chains between Pb-I layers, exhibit only one excitonic emission peak, as well as a large exciton-phonon coupling strength. Our work clarifies the influence of exciton-phonon coupling on the excitonic emission of (BA)2PbI4 microplates, and also suggests the intrinsic relationship between the exciton-phonon coupling and the length of organic carbon chain ligands.

15.
Nat Commun ; 13(1): 3794, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778392

RESUMO

The DEAD box protein DDX1, previously associated with 3'-end RNA processing and DNA repair, forms large aggregates in the cytoplasm of early mouse embryos. Ddx1 knockout causes stalling of embryos at the 2-4 cell stages. Here, we identify a DDX1-containing membrane-bound calcium-containing organelle with a nucleic acid core. We show that aggregates of these organelles form ring-like structures in early-stage embryos which we have named Membrane Associated RNA-containing Vesicles. We present evidence that DDX1 is required for the formation of Membrane Associated RNA-containing Vesicles which in turn regulate the spatial distribution of calcium in embryos. We find that Ddx1 knockout in early embryos disrupts calcium distribution, and increases mitochondria membrane potential, mitochondrial activity, and reactive oxygen species. Sequencing analysis of embryos from Ddx1 heterozygote crosses reveals downregulation of a subset of RNAs involved in developmental and mitochondrial processes in the embryos with low Ddx1 RNA. We propose a role for Membrane Associated RNA-containing Vesicles in calcium-controlled mitochondrial functions that are essential for embryonic development.


Assuntos
Cálcio , RNA Helicases DEAD-box , Mitocôndrias , Animais , Cálcio/metabolismo , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Embrião de Mamíferos , Camundongos , Mitocôndrias/metabolismo , RNA/metabolismo , Processamento Pós-Transcricional do RNA
16.
Nanoscale ; 13(21): 9706-9722, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34018532

RESUMO

Brain fatty acid binding protein (FABP7; B-FABP) promotes glioblastoma (GBM) cell migration and is associated with tumor infiltration, properties associated with a poor prognosis in GBM patients. FABP7-expressing neural stem-like cells are known to drive tumor migration/infiltration and resistance to treatment. We have previously shown that FABP7's effects on cell migration can be reversed when GBM cells are cultured in medium supplemented with the omega-3 fatty acid, docosahexaenoic acid (DHA). Here, we use super-resolution imaging on patient-derived GBM stem-like cells to examine the importance of FABP7 and its fatty acid ligands in mitigating GBM cell migration. As FABPs are involved in fatty acid transport from membrane to cytosol, we focus on the effect of FABP7 and its ligand DHA on GBM membrane remodeling, as well as FABP7 nanoscale domain formation on GBM membrane. Using quantitative plasma membrane lipid order imaging, we show that FABP7 expression in GBM cells correlates with increased membrane lipid order, with DHA dramatically decreasing lipid order. Using super-resolution stimulated emission depletion (STED) microscopy, we observe non-uniform distribution of FABP7 on the surface of GBM cells, with FABP7 forming punctate nanoscale domains of ∼100 nm in diameter. These nanodomains are particularly enriched at the migrating front of GBM cells. Interestingly, FABP7 nanodomains are disrupted when GBM cells are cultured in DHA-supplemented medium. We demonstrate a tight link between cell migration, a higher membrane lipid order and increased FABP7 nanoscale domains. We propose that DHA-mediated disruption of membrane lipid order and FABP7 nanodomains forms the basis of FABP7/DHA-mediated inhibition of cell migration in GBM.


Assuntos
Glioblastoma , Movimento Celular , Ácidos Docosa-Hexaenoicos/farmacologia , Proteína 7 de Ligação a Ácidos Graxos , Humanos , Microscopia
17.
Nutrients ; 13(8)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34444824

RESUMO

Glioblastoma (GBM) is an aggressive tumor with a dismal prognosis. Neural stem-like cells contribute to GBM's poor prognosis by driving drug resistance and maintaining cellular heterogeneity. GBM neural stem-like cells express high levels of brain fatty acid-binding protein (FABP7), which binds to polyunsaturated fatty acids (PUFAs) ω-6 arachidonic acid (AA) and ω-3 docosahexaenoic acid (DHA). Similar to brain, GBM tissue is enriched in AA and DHA. However, DHA levels are considerably lower in GBM tissue compared to adult brain. Therefore, it is possible that increasing DHA content in GBM, particularly in neural stem-like cells, might have therapeutic value. Here, we examine the fatty acid composition of patient-derived GBM neural stem-like cells grown as neurosphere cultures. We also investigate the effect of AA and DHA treatment on the fatty acid profiles of GBM neural stem-like cells with or without FABP7 knockdown. We show that DHA treatment increases DHA levels and the DHA:AA ratio in GBM neural stem-like cells, with FABP7 facilitating the DHA uptake. We also found that an increased uptake of DHA inhibits the migration of GBM neural stem-like cells. Our results suggest that increasing DHA content in the GBM microenvironment may reduce the migration/infiltration of FABP7-expressing neural stem-like cancer cells.


Assuntos
Neoplasias Encefálicas/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Proteína 7 de Ligação a Ácidos Graxos/metabolismo , Glioblastoma/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ácido Araquidônico/metabolismo , Transporte Biológico , Encéfalo/metabolismo , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Movimento Celular , Ácidos Docosa-Hexaenoicos/farmacologia , Proteína 7 de Ligação a Ácidos Graxos/genética , Proteínas de Ligação a Ácido Graxo/metabolismo , Ácidos Graxos , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-6/metabolismo , Ácidos Graxos Insaturados/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Humanos , Fosfolipídeos/metabolismo , Prognóstico , Microambiente Tumoral/efeitos dos fármacos , Proteínas Supressoras de Tumor/genética
18.
J Gastrointest Oncol ; 11(6): 1322-1332, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33457004

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is a fatal malignant tumor with a poor prognosis, and is the third leading cause of cancer-related deaths worldwide. This study aimed to investigate the anti-tumor effect of propofol on the proliferation, apoptosis, and cell cycle of HCC by regulating adenosine monophosphate-activated protein kinase (AMPK) in vivo and in vitro. METHODS: The cell counting Kit-8 (CCK-8) assay was employed to screen the effect of propofol on HepG2 cell viability at various concentrations (0.3, 0.6, 1.2, 2.5, 5, 10, 20, 40, 80 and 160 µM). We selected propofol at concentrations of 5, 10 and 20 µM for subsequent experiments. Flow cytometry was used to examine the apoptosis and cell cycle of HCC. Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) was applied to measure the messenger ribonucleic acid (mRNA) expression levels of proliferating cell nuclear antigen (PCNA) and survivin. Western blotting was applied to measure the protein expression levels of PCNA, survivin, cleaved caspase-3, cleaved caspase-9, p27 (Kip1), and cyclin A. The effects of propofol were evaluated by establishing a xenograft tumor model. RESULTS: After treatment with propofol, the mRNA expression levels of PCNA and survivin were decreased compared with the 0 µM propofol (control) group. The colony formation assay showed that the colony formation rate was obviously down-regulated. Flow cytometry demonstrated that HepG2 cell apoptosis was increased. G0/G1 was enhanced compared with the control group, while G2/M was restrained. The levels of cleaved caspase-3, cleaved caspase-9, p27, phospho-AMP-activated protein kinase α1 (p-AMPKα1), phospho-mammalian target of rapamycin (p-mTOR), and phospho-Unc-51 like autophagy activating kinase 1 (p-ULK1) were notably elevated, while the levels of cyclin A were suppressed. The xenograft tumor volume declined in vivo compared with the HepG2 xenograft group. The expression levels of cell proliferation markers (PCNA) were significantly down-regulated markedly, while the expression levels of cell cycle markers (p27) were notablyup-regulated. Terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) staining showed that cell apoptosis was increased. The levels of p-AMPKα1 were also up-regulated. CONCLUSIONS: Propofol inhibits the proliferation, apoptosis, and cell cycle of HCC by regulating AMPK in vivo and in vitro.

19.
Acta Crystallogr C Struct Chem ; 75(Pt 2): 150-160, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30720453

RESUMO

The design and synthesis of metal-organic frameworks (MOFs) have attracted much interest due to the intriguing diversity of their architectures and topologies. However, building MOFs with different topological structures from the same ligand is still a challenge. Using 3-nitro-4-(pyridin-4-yl)benzoic acid (HL) as a new ligand, three novel MOFs, namely poly[[(N,N-dimethylformamide-κO)bis[µ2-3-nitro-4-(pyridin-4-yl)benzoato-κ3O,O':N]cadmium(II)] N,N-dimethylformamide monosolvate methanol monosolvate], {[Cd(C12H7N2O4)2(C3H7NO)]·C3H7NO·CH3OH}n, (1), poly[[(µ2-acetato-κ2O:O')[µ3-3-nitro-4-(pyridin-4-yl)benzoato-κ3O:O':N]bis[µ3-3-nitro-4-(pyridin-4-yl)benzoato-κ4O,O':O':N]dicadmium(II)] N,N-dimethylacetamide disolvate monohydrate], {[Cd2(C12H7N2O4)3(CH3CO2)]·2C4H9NO·H2O}n, (2), and catena-poly[[[diaquanickel(II)]-bis[µ2-3-nitro-4-(pyridin-4-yl)benzoato-κ2O:N]] N,N-dimethylacetamide disolvate], {[Ni(C12H7N2O4)2(H2O)2]·2C4H9NO}n, (3), have been prepared. Single-crystal structure analysis shows that the CdII atom in MOF (1) has a distorted pentagonal bipyramidal [CdN2O5] coordination geometry. The [CdN2O5] units as 4-connected nodes are interconnected by L- ligands to form a fourfold interpenetrating three-dimensional (3D) framework with a dia topology. In MOF (2), there are two crystallographically different CdII ions showing a distorted pentagonal bipyramidal [CdNO6] and a distorted octahedral [CdN2O4] coordination geometry, respectively. Two CdII ions are connected by three carboxylate groups to form a binuclear [Cd2(COO)3] cluster. Each binuclear cluster as a 6-connected node is further linked by acetate groups and L- ligands to produce a non-interpenetrating 3D framework with a pcu topology. MOF (3) contains two crystallographically distinct NiII ions on special positions. Each NiII ion adopts an elongated octahedral [NiN2O4] geometry. Each NiII ion as a 4-connected node is linked by L- ligands to generate a two-dimensional network with an sql topology, which is further stabilized by two types of intermolecular OW-HW...O hydrogen bonds to form a 3D supramolecular framework. MOFs (1)-(3) were also characterized by powder X-ray diffraction, IR spectroscopy and thermogravimetic analysis. Furthermore, the solid-state photoluminescence of HL and MOFs (1) and (2) have been investigated. The photoluminescence of MOFs (1) and (2) are enhanced and red-shifted with respect to free HL. The gas adsorption investigation of MOF (2) indicates a good separation selectivity (71) of CO2/N2 at 273 K (i.e. the amount of CO2 adsorption is 71 times higher than N2 at the same pressure).

20.
Mol Med Rep ; 19(6): 4655-4662, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059003

RESUMO

Preeclampsia remains a major cause of maternal mortality and morbidity worldwide. It is generally accepted that the development of the placenta, including spiral artery remodelling, normal trophoblast cells function and maternal­fetal inflammation­immune interactions, is critical for the pathogenesis of preeclampsia. Several investigations have demonstrated that microRNAs (miRNAs/miRs) in the placenta may be potential molecular markers for diagnosis of preeclampsia. In the current study, the aim was to investigate the expression of miR­144­3p in the placenta of patients with preeclampsia and normal placentas, and to explore the potential target genes. miRNA microarray analysis was performed using three paired placentas (preeclampsia and normal) in order to find differential expression of miRNAs. Following this, miR­144­3p was selected as a differentially expressed miRNA and validated using in situ hybridization to determine the clinical significance in placentas with preeclampsia. A potential target gene of miR­144­3p, cyclooxygenase­2 (Cox­2), was identified by bioinformatics, luciferase reporter assay and western blotting. The expression of Cox­2 was also examined by immunohistochemical staining of samples of placenta from patients with preeclampsia and normal placenta. Western blot analysis was performed to investigate the effect of miR­144­3p on the expression of Cox­2 in HTR­8/SVneo cells in vitro. miR­144­3p was decreased in placentas from patients with preeclampsia. A luciferase reporter assay demonstrated that Cox­2 was a potential miR­144­3p target gene and the result was verified by western blotting. A negative correlation was observed between miR­144­3p and Cox­2 in preeclamptic placenta by immunohistochemical staining and in situ hybridization. Western blot analysis demonstrated that overexpression of miR­144­3p decreased Cox­2 expression by 38.2% in HTR­8/SVneo cells. Understanding the differential expression of miR­144­3p and its association with Cox­2 may aid the exploration of the pathogenesis of preeclampsia, and contribute to the development of miRNA­based therapies in the future.


Assuntos
Ciclo-Oxigenase 2/genética , MicroRNAs/genética , Pré-Eclâmpsia/terapia , Adulto , Estudos de Casos e Controles , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Feminino , Regulação da Expressão Gênica , Marcação de Genes , Marcadores Genéticos , Humanos , Hibridização In Situ , MicroRNAs/metabolismo , Placenta , Pré-Eclâmpsia/genética , Gravidez , Adulto Jovem
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