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1.
J Transl Med ; 22(1): 528, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824544

RESUMO

Given the insidious and high-fatality nature of cardiovascular diseases (CVDs), the emergence of fluoride as a newly identified risk factor demands serious consideration alongside traditional risk factors. While vascular smooth muscle cells (VSMCs) play a pivotal role in the progression of CVDs, the toxicological impact of fluoride on VSMCs remains largely uncharted. In this study, we constructed fluorosis model in SD rats and A7R5 aortic smooth muscle cell lines to confirm fluoride impaired VSMCs. Fluoride aggravated the pathological damage of rat aorta in vivo. Then A7R5 were exposed to fluoride with concentration ranging from 0 to 1200 µmol/L over a 24-h period, revealing a dose-dependent inhibition of cell proliferation and migration. The further metabolomic analysis showed alterations in metabolite profiles induced by fluoride exposure, notably decreasing organic acids and lipid molecules level. Additionally, gene network analysis underscored the frequency of fluoride's interference with amino acids metabolism, potentially impacting the tricarboxylic acid (TCA) cycle. Our results also highlighted the ATP-binding cassette (ABC) transporters pathway as a central element in VSMC impairment. Moreover, we observed a dose-dependent increase in osteopontin (OPN) and α-smooth muscle actin (α-SMA) mRNA level and a dose-dependent decrease in ABC subfamily C member 1 (ABCC1) and bestrophin 1 (BEST1) mRNA level. These findings advance our understanding of fluoride as a CVD risk factor and its influence on VSMCs and metabolic pathways, warranting further investigation into this emerging risk factor.


Assuntos
Aminoácidos , Proliferação de Células , Fluoretos , Músculo Liso Vascular , Ratos Sprague-Dawley , Animais , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Músculo Liso Vascular/efeitos dos fármacos , Fluoretos/farmacologia , Linhagem Celular , Aminoácidos/metabolismo , Proliferação de Células/efeitos dos fármacos , Ratos , Movimento Celular/efeitos dos fármacos , Masculino , Aorta/patologia , Aorta/efeitos dos fármacos , Aorta/metabolismo , Metabolômica , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/patologia , Redes Reguladoras de Genes/efeitos dos fármacos
2.
Nat Commun ; 15(1): 1838, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418810

RESUMO

Plastic crystals as barocaloric materials exhibit the large entropy change rivalling freon, however, the limited pressure-sensitivity and large hysteresis of phase transition hinder the colossal barocaloric effect accomplished reversibly at low pressure. Here we report reversible colossal barocaloric effect at low pressure in two-dimensional van-der-Waals alkylammonium halides. Via introducing long carbon chains in ammonium halide plastic crystals, two-dimensional structure forms in (CH3-(CH2)n-1)2NH2X (X: halogen element) with weak interlayer van-der-Waals force, which dictates interlayer expansion as large as 13% and consequently volume change as much as 12% during phase transition. Such anisotropic expansion provides sufficient space for carbon chains to undergo dramatic conformation disordering, which induces colossal entropy change with large pressure-sensitivity and small hysteresis. The record reversible colossal barocaloric effect with entropy change ΔSr ~ 400 J kg-1 K-1 at 0.08 GPa and adiabatic temperature change ΔTr ~ 11 K at 0.1 GPa highlights the design of novel barocaloric materials by engineering the dimensionality of plastic crystals.

3.
J Chromatogr Sci ; 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37647634

RESUMO

Pinus massoniana needles, a traditional herb, were applied to prevent hair loss in China. Studies available mainly focused on pine needle flavonoids with various biological activities. However, there has been no pharmacokinetics study of the flavonoids from Pinus needles extract. A selective and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to simultaneously quantify taxifolin, quercetin and catechin in rat plasma. To separate the three constituents, an Agilent Extend-C18 column (2.1 mm × 100 mm, 1.8 µm) was used with a mobile phrase of (A) 0.1% formic acid and (B) acetonitrile. The analytes were measured by multiple reaction monitoring in the negative ionization mode. There was good linearity in the established UHPLC-MS/MS method, with a coefficient of determination (r2) of >0.99. The accuracy, intra-day and inter-day precision and recovery were all satisfactory and these 3 compounds were stable under the tested conditions. The validated method in this study was successfully applied to pharmacokinetic study in healthy rats after oral and transdermal administration of Pinus needles extract. The results could provide further research foundation for pine needle extract as external preparations.

4.
J Neurosci ; 43(24): 4525-4540, 2023 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37188517

RESUMO

Our recent study demonstrated the critical role of the mesolimbic dopamine (DA) circuit and its brain-derived neurotropic factor (BDNF) signaling in mediating neuropathic pain. The present study aims to investigate the functional role of GABAergic inputs from the lateral hypothalamus (LH) to the ventral tegmental area (VTA; LHGABA→VTA) in regulating the mesolimbic DA circuit and its BDNF signaling underlying physiological and pathologic pain. We demonstrated that optogenetic manipulation of the LHGABA→VTA projection bidirectionally regulated pain sensation in naive male mice. Optogenetic inhibition of this projection generated an analgesic effect in mice with pathologic pain induced by chronic constrictive injury (CCI) of the sciatic nerve and persistent inflammatory pain by complete Freund's adjuvant (CFA). Trans-synaptic viral tracing revealed a monosynaptic connection between LH GABAergic neurons and VTA GABAergic neurons. Functionally, in vivo calcium/neurotransmitter imaging showed an increased DA neuronal activity, decreased GABAergic neuronal activity in the VTA, and increased dopamine release in the NAc, in response to optogenetic activation of the LHGABA→VTA projection. Furthermore, repeated activation of the LHGABA→VTA projection was sufficient to increase the expression of mesolimbic BDNF protein, an effect seen in mice with neuropathic pain. Inhibition of this circuit induced a decrease in mesolimbic BDNF expression in CCI mice. Interestingly, the pain behaviors induced by activation of the LHGABA→VTA projection could be prevented by pretreatment with intra-NAc administration of ANA-12, a TrkB receptor antagonist. These results demonstrated that LHGABA→VTA projection regulated pain sensation by targeting local GABAergic interneurons to disinhibit the mesolimbic DA circuit and regulating accumbal BDNF release.SIGNIFICANCE STATEMENT The mesolimbic dopamine (DA) system and its brain-derived neurotropic factor (BDNF) signaling have been implicated in pain regulation, however, underlying mechanisms remain poorly understood. The lateral hypothalamus (LH) sends different afferent fibers into and strongly influences the function of mesolimbic DA system. Here, utilizing cell type- and projection-specific viral tracing, optogenetics, in vivo calcium and neurotransmitter imaging, our current study identified the LHGABA→VTA projection as a novel neural circuit for pain regulation, possibly by targeting the VTA GABA-ergic neurons to disinhibit mesolimbic pathway-specific DA release and BDNF signaling. This study provides a better understanding of the role of the LH and mesolimbic DA system in physiological and pathological pain.


Assuntos
Dopamina , Neuralgia , Camundongos , Masculino , Animais , Dopamina/metabolismo , Região Hipotalâmica Lateral/fisiologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Cálcio/metabolismo , Área Tegmentar Ventral/fisiologia , Neurônios GABAérgicos/fisiologia , Ácido gama-Aminobutírico/metabolismo , Neuralgia/metabolismo , Sensação , Núcleo Accumbens/fisiologia
5.
Mol Plant ; 16(6): 999-1015, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37050877

RESUMO

The orderly deposition of secondary cell wall (SCW) in plants is implicated in various biological programs and is precisely controlled. Although many positive and negative regulators of SCW have been documented, the molecular mechanisms underlying SCW formation coordinated with distinct cellular physiological processes during plant adaptive growth remain largely unclear. Here, we report the identification of Cellulose Synthase co-expressed Kinase1 (CSK1), which encodes a receptor-like cytoplasmic kinase, as a negative regulator of SCW formation and its signaling cascade in rice. Transcriptome deep sequencing of developing internodes and genome-wide co-expression assays revealed that CSK1 is co-expressed with cellulose synthase genes and is responsive to various stress stimuli. The increased SCW thickness and vigorous vessel transport in csk1 indicate that CSK1 functions as a negative regulator of SCW biosynthesis. Through observation of green fluorescent protein-tagged CSK1 in rice protoplasts and stable transgenic plants, we found that CSK1 is localized in the nucleus and cytoplasm adjacent to the plasma membrane. Biochemical and molecular assays demonstrated that CSK1 phosphorylates VASCULAR-RELATED NAC-DOMAIN 6 (VND6), a master SCW-associated transcription factor, in the nucleus, which reduces the transcription of a suite of SCW-related genes, thereby attenuating SCW accumulation. Consistently, genetic analyses show that CSK1 functions upstream of VND6 in regulating SCW formation. Interestingly, our physiological analyses revealed that CSK1 and VND6 are involved in abscisic acid-mediated regulation of cell growth and SCW deposition. Taken together, these results indicate that the CSK1-VND6 module is an important component of the SCW biosynthesis machinery, which coordinates SCW accumulation and adaptive growth in rice. Our study not only identifies a new regulator of SCW biosynthesis but also reveals a fine-tuned mechanism for precise control of SCW deposition, offering tools for rationally tailoring agronomic traits.


Assuntos
Oryza , Oryza/genética , Oryza/metabolismo , Fatores de Transcrição/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas
6.
AAPS PharmSciTech ; 24(4): 82, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36949351

RESUMO

Glioma, in which a malignant tumor cell occurs in neural mesenchymal cells, has a rapid progression and poor prognosis, which is still far from desirable in clinical treatments. We developed a lab-on-a-chip (LOC) device for the rapid and efficient preparation of vitexin/indocyanine green (ICG) liposomes. Vitexin could be released from liposome to kill cancer cell, which can potentially improve the glioma therapeutic effect and reduce the treatment time through synergistic photodynamic/photothermal therapies (PDT/PTT). The vitexin/ICG liposome was fabricated via LOC and its physicochemical property and release in vitro were evaluated. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method and live/dead staining were used to examine the enhanced antitumor effect of vitexin/ICG liposome in cooperation with PDT/PTT, while the related mechanism was explored by flow cytometry and western blot. The results were as follows: (1) The prepared vitexin/ICG liposome was smaller in size, homogenous in particle size distribution with significant low polydispersity index (PDI), and enhanced cumulative release in vitro. (2) We found that the formulated liposome presented strong cancer cell inhibition and suppression of its migration in a dose-dependent manner. (3) Further mechanistic studies showed that liposome combined with near-infrared irradiation could significantly upregulate levels of B cell lymphoma 2-associated X (Bax) protein and decrease B cell lymphoma 2 (Bcl-2) at protein levels. The vitexin/ICG liposomes prepared based on a simple LOC platform can effectively enhance the solubility of insoluble drugs, and the combined effect of PTT/PDT can effectively increase their antitumor effect, which provides a simple and valid method for the clinical translation of liposomes.


Assuntos
Glioma , Fotoquimioterapia , Humanos , Verde de Indocianina/química , Verde de Indocianina/farmacologia , Verde de Indocianina/uso terapêutico , Lipossomos/química , Fotoquimioterapia/métodos , Microfluídica , Glioma/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2 , Linhagem Celular Tumoral
7.
Br J Anaesth ; 130(4): 446-458, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36737387

RESUMO

BACKGROUND: Corticotropin-releasing factor (CRF) neurones in the paraventricular nucleus (PVN) of the hypothalamus (PVNCRF neurones) can promote wakefulness and are activated under anaesthesia. However, whether these neurones contribute to anaesthetic effects is unknown. METHODS: With a combination of chemogenetic and molecular approaches, we examined the roles of PVNCRF neurones in isoflurane anaesthesia in mice and further explored the underlying cellular and molecular mechanisms. RESULTS: PVN neurones exhibited increased Fos expression during isoflurane anaesthesia (mean [standard deviation], 218 [69.3] vs 21.3 [7.3]; P<0.001), and ∼75% were PVNCRF neurones. Chemogenetic inhibition of PVNCRF neurones facilitated emergence from isoflurane anaesthesia (11.7 [1.1] vs 13.9 [1.2] min; P=0.001), whereas chemogenetic activation of these neurones delayed emergence from isoflurane anaesthesia (16.9 [1.2] vs 13.9 [1.3] min; P=0.002). Isoflurane exposure increased CRF protein expression in PVN (4.0 [0.1] vs 2.2 [0.3], respectively; P<0.001). Knockdown of CRF in PVNCRF neurones mimicked the effects of chemogenetic inhibition of PVNCRF neurones in facilitating emergence (9.6 [1.1] vs 13.0 [1.4] min; P=0.003) and also abolished the effects of chemogenetic activation of PVNCRF neurones on delaying emergence from isoflurane anaesthesia (10.3 [1.3] vs 16.0 [2.6] min; P<0.001). Acute, but not chronic, stress delayed emergence from isoflurane anaesthesia (15.5 [1.5] vs 13.0 [1.4] min; P=0.004). This effect was reversed by chemogenetic inhibition of PVNCRF neurones (11.7 [1.6] vs 14.7 [1.4] min; P=0.001) or knockdown of CRF in PVNCRF neurones (12.3 [1.5] vs 15.3 [1.6] min; P=0.002). CONCLUSIONS: CRF neurones in the PVN of the hypothalamus neurones modulate isoflurane anaesthesia and acute stress effects on anaesthesia through CRF signalling.


Assuntos
Anestesia , Isoflurano , Camundongos , Animais , Hormônio Liberador da Corticotropina/metabolismo , Hormônio Liberador da Corticotropina/farmacologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Isoflurano/farmacologia , Hipotálamo/metabolismo
8.
Front Med (Lausanne) ; 9: 1009578, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438037

RESUMO

Background: Several studies on Caucasians have revealed a positive relationship between androgenetic alopecia (AGA) and metabolic syndrome (MS). However, this correlation varies in different contexts. Currently, the association of AGA with MS is yet to be studied and elucidated in Chinese people. Objective: To evaluate the association between AGA and MS in the Chinese population. Methods: This study included information on components of MS along with other possible risk factors in a total of 3,703 subjects. The patients' loss of hair was assessed using Hamilton-Norwood and Ludwig classification method. Results: In this study, 29.88% of male and 27.58% of female AGA patients were diagnosed with MS, while the rest were regarded as controls (29.95% of male and 27.89% of female control subjects) (P > 0.05). The AGA males presented significantly higher systolic and diastolic blood pressure than the male control subjects (SP: P = 0.000; DP: P = 0.041). Among females with AGA, waist circumference, hip circumference, and waist-hip ratio elevated the loss of hair compared to that of the female controls (P = 0.000, P = 0.020, P = 0.001, respectively). Conclusion: Our study indicated no direct association between AGA and MS in Chinese people. However, a close relationship was observed between AGA and systolic blood pressure.

9.
ACS Nano ; 16(9): 14632-14643, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36107149

RESUMO

Modifying the crystal structure and corresponding functional properties of complex oxides by regulating their oxygen content has promising applications in energy conversion and chemical looping, where controlling oxygen migration plays an important role. Therefore, finding an efficacious and feasible method to facilitate oxygen migration has become a critical requirement for practical applications. Here, we report a compressive-strain-facilitated oxygen migration with reversible topotactic phase transformation (RTPT) in La0.5Sr0.5CoOx films based on all-solid-state electrolyte gating modulation. With the lattice strain changing from tensile to compressive strain, significant reductions in modulation duration (∼72%) and threshold voltage (∼70%) for the RTPT were observed, indicating great promotion of RTPT by compressive strain. Density functional theory calculations verify that such compressive-strain-facilitated efficient RTPT comes from significant reduction of the oxygen migration barrier in compressive-strained films. Further, ac-STEM, EELS, and sXAS investigations reveal that varying strain from tensile to compressive enhances the Co 3d band filling, thereby suppressing the Co-O hybrid bond in oxygen vacancy channels, elucidating the micro-origin of such compressive-strain-facilitated oxygen migration. Our work suggests that controlling electronic orbital occupation of Co ions in oxygen vacancy channels may help facilitate oxygen migration, providing valuable insights and practical guidance for achieving highly efficient oxygen-migration-related chemical looping and energy conversion with complex oxides.

10.
RSC Adv ; 12(36): 23503-23512, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36090447

RESUMO

For electrocatalytic hydrogen evolution in acidic environments, the stability of catalysts has always been a significant factor restricting development. Here, we prepared a superstable SnO2/MoS2 coupled nanosheet array on carbon cloth (CC@SnO2/MoS2), exhibiting an overpotential of 166 mV at a current density of 10 mA cm-2. According to the results of various tests and theoretical calculations, it is shown that the establishment of SnO2/MoS2 interface engineering is to accelerate the electron transmission on the heterogeneous interface and S defects on the edge of MoS2, and finally improve the conductivity and catalytic activity of the catalyst. More importantly, the formation of an SnO2 interface layer during in situ transformation improves the stability and hydrophilicity of the material surface. We have proposed a strategy for engineering an interface with fast electron transport and proton adsorption, providing some new ideas for the design of HER catalysts in acid electrolytes.

11.
Plant Cell ; 34(12): 4778-4794, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-35976113

RESUMO

Glycosylphosphatidylinositol (GPI) anchoring is a common protein modification that targets proteins to the plasma membrane (PM). Knowledge about the GPI lipid tail, which guides the secretion of GPI-anchored proteins (GPI-APs), is limited in plants. Here, we report that rice (Oryza sativa) BRITTLE CULM16 (BC16), a membrane-bound O-acyltransferase (MBOAT) remodels GPI lipid tails and governs cell wall biomechanics. The bc16 mutant exhibits fragile internodes, resulting from reduced cell wall thickness and cellulose content. BC16 is the only MBOAT in rice and is located in the endoplasmic reticulum and Golgi apparatus. Yeast gup1Δ mutant restoring assay and GPI lipid composition analysis demonstrated BC16 as a GPI lipid remodelase. Loss of BC16 alters GPI lipid structure and disturbs the targeting of BC1, a GPI-AP for cellulose biosynthesis, to the PM lipid nanodomains. Atomic force microscopy revealed compromised deposition of cellulosic nanofibers in bc16, leading to an increased Young's modulus and abnormal mechanical properties. Therefore, BC16-mediated lipid remodeling directs the GPI-APs, such as BC1, to the cell surface to fulfill multiple functions, including cellulose organization. Our work unravels a mechanism by which GPI lipids are remodeled in plants and provides insights into the control of cell wall biomechanics, offering a tool for breeding elite crops with improved support strength.


Assuntos
Glicosilfosfatidilinositóis , Complexo de Golgi , Glicosilfosfatidilinositóis/metabolismo , Complexo de Golgi/metabolismo , Membrana Celular/metabolismo , Saccharomyces cerevisiae/metabolismo , Aciltransferases/metabolismo , Parede Celular/metabolismo , Celulose/metabolismo
12.
ACS Appl Mater Interfaces ; 14(16): 18293-18301, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35418228

RESUMO

The cyclability and frequency dependence of the adiabatic temperature change (ΔTad) under an alternating magnetic field (AMF) are significantly important from the viewpoint of refrigeration application. Our studies demonstrated, by direct measurements, that the cyclability and low-magnetic-field performance of ΔTad in FeRh alloys can be largely enhanced by introducing second phases. The ΔTad under a 1.8 T, 0.13 Hz AMF is reduced by 14%, which is much better than that (40-50%) of monophase FeRh previously reported. More importantly, the introduction of second phases enables the antiferromagnetic-ferromagnetic phase transition to be driven by a lower magnetic field. Thus, ΔTad is significantly enhanced under a 0.62 T, 1 Hz AMF, and its value is 70% larger than that of monophase FeRh previously reported. Although frequency dependence of ΔTad occurs, the specific cooling power largely increases by 11 times from 0.17 to 1.9 W/g, as the frequency increases from 1 to 18.4 Hz under an AMF of 0.62 T. Our analysis of the phase transition dynamics based on magnetic relaxation measurements indicates that the activation energy barrier is lowered owing to the existence of second phases in FeRh alloys, which should be responsible for the reduction of the driving field. This work provides an effective way to enhance the cyclability and low-magnetic-field performance of ΔTad under an AMF in FeRh alloys by introducing second phases.

13.
Nat Plants ; 8(3): 295-306, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35318447

RESUMO

Nanoclustering of biomacromolecules allows cells to efficiently orchestrate biological processes. The plant cell wall is a highly organized polysaccharide network but is heterogeneous in chemistry and structure. However, polysaccharide-based nanocompartments remain ill-defined. Here, we identify a xylan-rich nanodomain at pit borders of xylem vessels. We show that these nanocompartments maintain distinct wall patterns by anchoring cellulosic nanofibrils at the pit borders, critically supporting vessel robustness, water transport and leaf transpiration. The nanocompartments are produced by the activity of IRREGULAR XYLEM (IRX)10 and its homologues, which we show are de novo xylan synthases. Our study hence outlines a mechanism of how xylans are synthesized, how they assemble into nanocompartments and how the nanocompartments sustain cell wall pit patterning to support efficient water transport throughout the plant body.


Assuntos
Xilanos , Xilema , Membrana Celular , Parede Celular , Polissacarídeos
14.
15.
Front Mol Neurosci ; 15: 1083671, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36590915

RESUMO

Background: Besides the established role of dopamine neurons and projections in nociceptive stimuli, the involvement of ventral tegmental area (VTA) glutamatergic projections to nucleus accumbens (NAc) in pain remains unknown. In the present study, we aimed to examine the role of VTA glutamatergic projections to NAc in painful stimuli and its related behavioral changes. Methods: Unilateral chronic constrictive injury (CCI) of sciatic nerve or intraplantar hind paw injections (i.pl.) of complete Freund's adjuvant (CFA) were used to develop pathological pain models in wild-type and VGluT2-Cre mice. The involvement of VTA glutamatergic neurons with projections to NAc in CCI-induced pain model was noted by c-Fos labeling and firing rate recordings. Pain response and pain-related behavior changes to the artificial manipulation of the VTA glutamatergic projections to NAc were observed by Hargreaves tests, von Frey tests, open field tests, elevated maze tests, and sucrose preference tests. Results: Glutamatergic neurons in VTA had efferent inputs to shell area of the NAc. The CCI pain model significantly increased neuronal activity and firing rate in VTA glutamate neurons with projections to NAc. The photoinhibition of these glutamatergic projections relieved CCI-induced neuropathic pain and CFA-induced acute and chronic inflammatory pain. Moreover, pathological neuropathic pain-induced anxiety and less sucrose preference were also relieved by inhibiting the VTA glutamatergic projections to NAc. Conclusion: Together, glutamatergic inputs from VTA to NAc contribute to chronic neuropathic and inflammatory pain and pain-related anxiety and depressive behaviors, providing a mechanism for developing novel therapeutic methods.

16.
J Am Chem Soc ; 143(18): 6798-6804, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33938744

RESUMO

Spin structure of a magnetic system results from the competition of various exchange couplings. Pressure-driven spin structure evolution, through altering interatomic distance, and hence, electronic structure produces baromagnetic effect (BME), which has potential applications in sensor/actuator field. Here, we report a new spin structure(CyS-AFMb) with antiferromagnetic(AFM) nature in Fe-doped Mn0.87Fe0.13NiGe. Neutron powder diffraction (NPD) under in situ hydrostatic pressure and magnetic field was conducted to reveal the spin configuration and its instabilities. We discovered that a pressure higher than 4 kbar can induce abnormal change of Mn(Fe)-Mn(Fe) distances and transform the CyS-AFMb into a conical spiral ferromagnetic(FM) configuration(45°-CoS-FMa) with easily magnetized but shortened magnetic moment by as much as 22%. The observed BME far exceeds previous reports. Our first-principles calculations provide theoretical supports for the enhanced BME. The compressed lattice by pressure favors the 45°-CoS-FMa and significantly broadened 3d bandwidth of Mn(Fe) atoms, which leads to the shortened magnetic moment and evolution of spin structure.

17.
J Integr Plant Biol ; 63(1): 251-272, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33325153

RESUMO

The plant cell wall is composed of multiple biopolymers, representing one of the most complex structural networks in nature. Hundreds of genes are involved in building such a natural masterpiece. However, the plant cell wall is the least understood cellular structure in plants. Due to great progress in plant functional genomics, many achievements have been made in uncovering cell wall biosynthesis, assembly, and architecture, as well as cell wall regulation and signaling. Such information has significantly advanced our understanding of the roles of the cell wall in many biological and physiological processes and has enhanced our utilization of cell wall materials. The use of cutting-edge technologies such as single-molecule imaging, nuclear magnetic resonance spectroscopy, and atomic force microscopy has provided much insight into the plant cell wall as an intricate nanoscale network, opening up unprecedented possibilities for cell wall research. In this review, we summarize the major advances made in understanding the cell wall in this era of functional genomics, including the latest findings on the biosynthesis, construction, and functions of the cell wall.


Assuntos
Parede Celular/metabolismo , Microscopia de Força Atômica , Ressonância Magnética Nuclear Biomolecular
18.
Nat Commun ; 11(1): 5219, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060584

RESUMO

Nitrogen (N) is a macronutrient that boosts carbon (C) metabolism and plant growth leading to biomass accumulation. The molecular connection between nitrogen utilization efficiency (NUE) and biomass production remains unclear. Here, via quantitative trait loci analysis and map-based cloning, we reveal that natural variation at the MYB61 locus leads to differences in N use and cellulose biogenesis between indica and japonica subspecies of rice. MYB61, a transcriptional factor that regulates cellulose synthesis, is directly regulated by a known NUE regulator GROWTH-REGULATING FACTOR4 (GRF4), which coordinates cellulosic biomass production and N utilization. The variation at MYB61 has been selected during indica and japonica domestication. The indica allele of MYB61 displays robust transcription resulting in higher NUE and increased grain yield at reduced N supply than that of japonica. Our study hence unravels how C metabolism is linked to N uptake and may provide an opportunity to reduce N use for sustainable agriculture.


Assuntos
Nitrogênio/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Alelos , Biomassa , Celulose/biossíntese , Grão Comestível/genética , Grão Comestível/metabolismo , Regulação da Expressão Gênica de Plantas , Variação Genética , Desenvolvimento Vegetal , Locos de Características Quantitativas , Transdução de Sinais , Transcrição Gênica
19.
J Gene Med ; 22(12): e3278, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32997827

RESUMO

BACKGROUND: Growing evidence demonstrates that long non-coding RNAs (lncRNAs) play an important role in cancer origination and progression. A novel identified lncRNA, FGD5 antisense RNA 1 (FGD5-AS1), was reported to be overexpressed in several tumors. The present study aimed to investigate the expression of FGD5-AS1 in melanoma and its associations with clinical prognosis in melanoma patients. METHODS: The expression levels of FGD5-AS1 in 188 pairs of melanoma specimens and matched non-tumor specimens were determined using a real-time polymerase chain reaction. A chi-squared test was performed to determine the relationship between FGD5-AS1 levels and clinicopathological features. The overall survival rates of melanoma patients based on the expression of FGD5-AS1 were calculated by the Kaplan-Meier method with a log-rank test. Finally, univariate and multivariate assays were carried out to determine whether FGD5-AS1 was a prognostic factor in melanoma patients. RESULTS: We observed that FGD5-AS1 in melanoma specimens was distinctly up-regulated compared to adjacent non-tumor specimens (p < 0.01). In malignant cases, higher expression of FGD5-AS1 was prominently associated with tumor thickness (p = 0.024) and advanced tumor stage (p = 0.039). The data from our clinical study revealed that patients with high FGD5-AS1 expression had a distinctly shorter overall survival (p = 0.0034) and disease-free survival (p < 0.0001) than those with low FGD5-AS1 expression. Multivariate analysis demonstrated that high FGD5-AS1 expression may serve as a potential independent prognostic factor in melanoma. CONCLUSIONS: FGD5-AS1 may act as a prognostic predictor and a possible drug-target for melanoma patients.


Assuntos
Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Fatores de Troca do Nucleotídeo Guanina/genética , Melanoma/patologia , RNA Antissenso/genética , RNA Longo não Codificante/genética , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Melanoma/genética , Melanoma/metabolismo , Prognóstico , Taxa de Sobrevida
20.
Bioresour Technol ; 312: 123564, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32506041

RESUMO

Biochar was prepared by rapid pyrolysis using pine nut shell as raw materials. Then cetyl trimethyl ammonium bromide modified magnetic biochar material (CTAB-MC) was obtained after modifying biochar by FeCl3 and cetyl trimethyl ammonium bromide. The CTAB-MC was characterized by SEM, FTIR, XRD and Magnetic analyses. Adsorptive property of the CTAB-MC for acid chrome blue K (AK) was studied. It was found that adsorption capacity was affected by solution pH, temperature, adsorption time, initial concentration and ionic strength. The CTAB-MC showed higher adsorption ability toward acid chrome blue K, which was up to 40% higher than that of MC. The experimental results showed that adsorption data of AK on the CTAB-MC well conformed to the Langmuir isotherm adsorption model and the pseudo-second order kinetic model. The CTAB-MC can be recycled three times. This work reveals that CTAB-MC is a promising adsorbent with broad application prospects.


Assuntos
Cetrimônio , Poluentes Químicos da Água , Adsorção , Compostos Azo , Brometos , Carvão Vegetal , Cinética , Fenômenos Magnéticos , Naftalenossulfonatos , Nozes , Compostos de Amônio Quaternário
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