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1.
New Phytol ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38874377

RESUMEN

Wood is resulted from the radial growth paced by the division and differentiation of vascular cambium cells in woody plants, and phytohormones play important roles in cambium activity. Here, we identified that PagJAZ5, a key negative regulator of jasmonate (JA) signaling, plays important roles in enhancing cambium cell division and differentiation by mediating cytokinin signaling in poplar 84K (Populus alba × Populus glandulosa). PagJAZ5 is preferentially expressed in developing phloem and cambium, weakly in developing xylem cells. Overexpression (OE) of PagJAZ5m (insensitive to JA) increased cambium activity and xylem differentiation, while jaz mutants showed opposite results. Transcriptome analyses revealed that cytokinin oxidase/dehydrogenase (CKXs) and type-A response regulators (RRs) were downregulated in PagJAZ5m OE plants. The bioactive cytokinins were significantly increased in PagJAZ5m overexpressing plants and decreased in jaz5 mutants, compared with that in 84K plants. The PagJAZ5 directly interact with PagMYC2a/b and PagWOX4b. Further, we found that the PagRR5 is regulated by PagMYC2a and PagWOX4b and involved in the regulation of xylem development. Our results showed that PagJAZ5 can increase cambium activity and promote xylem differentiation through modulating cytokinin level and type-A RR during wood formation in poplar.

2.
Plant Cell Environ ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847345

RESUMEN

Shoot branching from axillary bud (AB) directly determines plant architecture. However, the mechanism through which AB remains dormant or emerges to form branches as plants grow remains largely unknown. Here, the auxin-strigolactone (IAA-SL) pathway was first shown to regulate shoot branching in poplar, and we found that PagKNAT2/6b could modulate this pathway. PagKNAT2/6b was expressed mainly in the shoot apical meristem and AB and was induced by shoot apex damage. PagKNAT2/6b overexpressing poplar plants (PagKNAT2/6b OE) exhibited multiple branches that mimicked the branching phenotype of nontransgenic plants after decapitation treatment, while compared with nontransgenic controls, PagKNAT2/6b antisense transgenic poplar and Pagknat2/6b mutant lines exhibited a significantly decreased number of branches after shoot apex damage treatment. In addition, we found that PagKNAT2/6b directly inhibits the expression of the key IAA synthesis gene PagYUC6a, which is specifically expressed in the shoot apex. Moreover, overexpression of PagYUC6a in the PagKNAT2/6b OE background reduced the number of branches after shoot apex damage treatment. Overall, we conclude that PagKNAT2/6b responds to shoot apical injury and regulates shoot branching through the IAA-SL pathway. These findings may provide a theoretical basis and candidate genes for genetic engineering to create new forest tree species with different crown types.

3.
Inorg Chem ; 63(15): 6871-6882, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38557029

RESUMEN

With increasing global industrialization, it is urgent and challenging to develop multifunctional species for detection and adsorption in the environment. For this purpose, a novel anionic heterometallic organic framework, [(CH3)2NH2][CaEu(CAM)2(H2O)2]·4H2O·4DMF (CaEuCAM), is hydrothermally synthesized based on chelidamic acid (H3CAM). Single crystal analysis shows that CaEuCAM features two different oxygen-rich channels along the c-axis in which one CAM3- bridges two sextuple-coordinated Ca2+ and two octuple-coordinated Eu3+ with a µ4-η1: η1: η1: η1: η1: η1 new chelating and bridging mode. The characteristic bright red emission and superior hydrostability of CaEuCAM under harsh acidic and basic conditions benefit it by acting as a highly sensitive sensor for Fe3+ and 3-nitrophenol (3-NP) with extremely low LODs through remarkable quenching. The combination of experiments and theoretical calculations for sensing mechanisms shows that the competitive absorption and interaction are responsible for Fe3+-induced selective emission quenching, while that for 3-NP is the result of the synergism of host-guest chemistry and the inner filter effect. Meanwhile, the assimilation of negative charge plus channels renders CaEuCAM a highly selective adsorbent for methylene blue (MB) due to a synergy of electrostatic affinity, ion-dipole interaction, and size matching. Of note is the reusability of CaEuCAM toward Fe3+/3-NP sensing and MB adsorption besides its fast response. These findings could be very useful in guiding the development of multifunctional Ln-MOFs for sensing and adsorption applications in water media.

4.
World J Psychiatry ; 13(10): 724-731, 2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-38058688

RESUMEN

BACKGROUND: The gut microbiome interacts with the central nervous system through the gut-brain axis, and this interaction involves neuronal, endocrine, and immune mechanisms, among others, which allow the microbiota to influence and respond to a variety of behavioral and mental conditions. AIM: To explore the correlation between cognitive impairment and gut microbiota imbalance in patients with schizophrenia. METHODS: A total of 498 untreated patients with schizophrenia admitted to our hospital from July 2020 to July 2022 were selected as the case group, while 498 healthy volunteers who underwent physical examinations at our hospital during the same period were selected as a control group. Fluorescence in situ hybridization was employed to determine the total number of bacteria in the feces of the two groups. The cognitive function test package was used to assess the score of cognitive function in each dimension. Then, the relationship between gut microbiota and cognitive function was analyzed. RESULTS: There were statistically significant differences in the relative abundance of gut microbiota at both phylum and class levels between the case group and the control group. In addition, the scores of cognitive function, such as atten-tion/alertness and learning ability, were significantly lower in the case group than in the control group (all P < 0.05). The cognitive function was positively correlated with Actinomycetota, Bacteroidota, Euryarchaeota, Fusobacteria, Pseudomonadota, and Saccharibacteria, while negatively correlated with Bacillota, Tenericutes, and Verrucomicrobia at the phylum level. While at the class level, the cognitive function was positively correlated with Class Actinobacteria, Bacteroidia, Betaproteobacteria, Proteobacteria, Blastomycetes, and Gammaproteobacteria, while negatively correlated with Bacilli, Clostridia, Coriobacteriia, and Verrucomicrobiae. CONCLUSION: There is a relationship between the metabolic results of gut microbiota and cognitive function in patients with schizophrenia. When imbalances occur in the gut microbiota of patients, it leads to more severe cognitive impairment.

5.
Dalton Trans ; 52(39): 14054-14063, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37740365

RESUMEN

The development of facile luminescent sensors for detecting nitrophenols in aqueous media is of great necessity for the safety of the environment and human health, as they are a class of widespread toxic organic pollutants that cause serious adverse effects upon consumption. Based on a new multidentate asymmetric ligand (H2L) in which salicylamide and 4-nitryl-salicylaldimine are spaced by 1,2-bis(2-ethoxy)ethyl, a new hydrostable lanthanide intercycle, [Tb2L2(NO3)2]·CH3CN (Tb-[2]c), was prepared to act as a new luminescent sensor for 4-NP in water media. Structural analysis indicated that two fully deprotonated L2- ligands in cis-configuration and µ2-L-κ2O1:κO2:κO4:κN2:κO5 coordination mode were interlocked by two TbIII ions to render the emitted TbIII encapsulated by L2- for lessening non-radiative transitions. The excellent sensitizing capability of the ligand L2- to TbIII was ascertained by both experimental methods and theoretical calculations. The sensing exploration indicated that Tb-[2]c exhibited highly sensitive and selective recognition of 4-NP against other nitroaromatics in aqueous media. The recognition mechanism could be attributed to the internal filtration effect (IFE) mechanism when DFT calculations and accumulating experimental evidence were combined.

6.
Front Plant Sci ; 14: 1196618, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37360718

RESUMEN

Programmed cell death (PCD) is a genetically regulated developmental process leading to the death of specific types of plant cells, which plays important roles in plant development and growth such as wood formation. However, an efficient method needs to be established to study PCD in woody plants. Flow cytometry is widely utilized to evaluate apoptosis in mammalian cells, while it is rarely used to detect PCD in plants, especially in woody plants. Here, we reported that the xylem cell protoplasts from poplar stem were stained with a combination of fluorescein annexin V-FITC and propidium iodide (PI) and then sorted by flow cytometry. As expected, living cells (annexin V-FITC negative/PI negative), early PCD cells (annexin V-FITC positive/PI negative), and late PCD cells (annexin V-FITC positive/PI positive) could be finely distinguished through this method and then subjected for quantitative analysis. The expression of cell-type- and developmental stages-specific marker genes was consistent with the cell morphological observation. Therefore, the newly developed fluorescence-activated cell sorting (FACS) method can be used to study PCD in woody plants, which will be beneficial for studying the molecular mechanisms of wood formation.

7.
Dalton Trans ; 51(7): 2962-2974, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35108721

RESUMEN

The effective monitoring of water pollution and further purification are pressing yet challenging issues for guaranteeing the health of human beings and the stabilization of ecological systems. For this purpose, the development of efficient sensing and adsorption materials as a result of supramolecular interactions, including coordination and H-bonding etc., have been attracting increasing attention. With the aid of a coordination-driven self-assembly strategy, a new nonporous 2D CuII coordination network, [Cu2L(H2O)2]n (donated as CuCP), based on H4L, where H4L = 4-(4-(3,5-di-carboxy-pyridin-4-yl)phenyl)pyridine-2,6-dicarboxylic acid, was afforded hydrothermally. Structural analysis indicated that CuCP featured a wrinkled network similar to the ancient Chinese folding screens and constructed by the fully deprotonated ligand L4- with the coordination mode of bis(µ2-η1:η1:η2) and penta-coordinated Cu2+, which could be further upgraded to a supramolecular 3D framework as a result of the synergism of multiple C-H⋯O hydrogen bonds. The hydrostability of CuCP could be maintained within a wide pH range from 2 to 12 as verified by PXRD determination, endowing it with potential environmental applications. Thanks to the combination of the soft Lewis acidity of Cu2+ and its large conjugated structure, CuCP could be used as a turn-on fluorescence sensor for S2- and exhibited a different fluorescence response when Na2S, (NH4)2S or H2S were incorporated, even in actual water samples. The sensing mechanisms were disclosed in detail by the combination of experiments and density functional theory (DFT) calculations. Furthermore, CuCP was shown to be a selective and recoverable adsorbent with a maximum adsorption capacity of 379 mg g-1 in 60 minutes for methylene blue (MB). The adsorption mechanism could be a combination of π⋯π stacking, n⋯π interaction, aggregation effects and Soft and Hard Acid-Base theory (HSAB). The results presented herein open up new perspectives for CuII species in environmental applications.


Asunto(s)
Azul de Metileno
8.
J Integr Plant Biol ; 64(1): 73-86, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34845845

RESUMEN

Wood is produced by the accumulation of secondary xylem via proliferation and differentiation of the cambium cells in woody plants. Identifying the regulators involved in this process remains a challenging task. In this study, we isolated PagSAG101a, the homolog of Arabidopsis thaliana SAG101, from a hybrid poplar (Populus alba × Populus glandulosa) clone 84K and investigated its role in secondary xylem development. PagSAG101a was expressed predominantly in lignified stems and localized in the nucleus. Compared with non-transgenic 84K plants, transgenic plants overexpressing PagSAG101a displayed increased plant height, internode number, stem diameter, xylem width, and secondary cell wall thickness, while opposite phenotypes were observed for PagSAG101a knock-out plants. Transcriptome analyses revealed that differentially expressed genes were enriched for those controlling cambium cell division activity and subsequent secondary cell wall deposition during xylem formation. In addition, the tandem CCCH zinc finger protein PagC3H17, which positively regulates secondary xylem width and secondary wall thickening in poplar, could bind to the promoter of PagSAG101a and mediate the regulation of xylem differentiation. Our results support that PagSAG101a, downstream of PagC3H17, functions in wood development.


Asunto(s)
Populus , Cámbium/genética , Cámbium/metabolismo , Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Populus/genética , Populus/metabolismo , Madera/genética , Xilema/genética
9.
Inorg Chem ; 60(22): 17051-17062, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34694111

RESUMEN

To advance the structural development and fully explore the application potential, it is highly desirable but challenging to elucidate the relationship between the structures and properties of ZnII-LnIII heterometallic species. Herein, three types of ZnII-LnIII heterometallic compounds (LnIII = GdIII, TbIII) formulated as [Zn16Ln4L12(µ3-O)4(NO3)12]·8CH3CN (ZnLn-1), [Zn2Ln2L2(NO3)6(H2O)2]·3CH3CN (ZnLn-2), and [Zn4Ln2L8(OAc)12]·xCH3CN (ZnLn-3: for Ln = Gd, x = 5; for Ln = Tb, x = 4) were dictated by common inorganic anions, NO3- and OAc-, with the aid of the multidentate ligand H2L with propane as the central skeleton and 3-methoxysalicylamide and 3-methoxysalicylaldimine as terminal groups. ZnLn-1 features cubic cages with four {Zn4L3} tetrahedral subunits and four Ln3+ centers positioned at the eight vertices alternately when NO3- was introduced into the reaction system exclusively. An attempt to replace NO3- in ZnLn-1 with OAc- partially led to the formation of {Zn2Ln2L2} heterometallic wheels. Meanwhile, ZnLn-3 featuring double-hairpin-like {Zn4Ln2L4} hemicycles that are orthogonal to each other assisted by intermolecular hydrogen bonds was constructed when NO3- in ZnLn-1 was completely replaced by OAc-. Their structural integrity in solution were ascertained by both emission and 1H NMR spectroscopy. Ascribed to the different Zn2+-containing antenna, ZnTb-2 possesses a relatively strong emission characteristic of Tb3+; ZnTb-1 has moderate Tb3+ luminescence, yet an absence of Tb3+ emission is found in ZnTb-3. Such an emission difference could be mainly attributed to the antenna effect directed by distinct structural characteristics induced by anions. The anion-dictated self-assembly strategy presented herein not only offers a facile approach to regulate the coordination mode of H2L to such an extent to obtain diverse structures of ZnII-LnIII heterometallic species but also provides an understanding of how common inorganic anions tune coordination-driven self-assemblies as well as the subsequent luminescence properties.

10.
Dalton Trans ; 50(44): 16110-16121, 2021 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-34668907

RESUMEN

From the perspective of human health and environmental safety, the development of hydrostable fluorescent sensors for the detection of heavy metal ions and nitroaromatics is an important but a challenging issue. To this end, a water-stable Zn2+ coordination polymer formulated as {[Zn(H2L)]·2DMF·3H2O}n (ZnCP) was prepared elaborately by a solvothermal method using a multidentate ligand (H4L) with 2,6-pyridine-dicarboxylic acid spaced by para-substituted benzene. Single-crystal analysis shows that the new ZnCP exhibits one-dimensional chain structural features, which further promoted to afford a wrinkled two-dimensional network structure via inter-chain hydrogen bonding. Powder X-ray diffraction and fluorescence measurements show that it can maintain crystallinity and structural integrity under harsh acidic and alkaline conditions with the pH ranging from 4 to 11. Notably, the bright blue-emissive ZnCP showed selective fluorescence quenching effects for Fe3+ and picric acid (PA), which makes it an excellent chemical sensor for Fe3+ and picric acid (PA) with low detection limits of 0.41 and 0.26 µM in water. The recognition mechanism of Fe3+ could be attributed to UV absorption competition and resonance energy transfer in the aid of weak electrostatic interactions, while the recognition mechanism of PA is considered to be a multi-quenching mechanism dominated by absorption competition and PET effects with the assistance of hydrogen bonding. In addition, poly(methyl methacrylate) (PMMA) films doped with ZnCP (ZnCP@PMMA) were developed to provide better sensing performance and portability for practical applications.

11.
J Musculoskelet Neuronal Interact ; 21(3): 397-400, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34465679

RESUMEN

Miyoshi myopathy (MM) is a rare autosomal recessive disorder caused by dysferlin (DYSF) gene mutation. Miyoshi myopathy-inducing mutation sites in the DYSF gene have been discovered worldwide. In the present study, a patient with progressive lower extremity weakness is reported, for which MM was diagnosed according to clinical manifestations, muscle biopsy, and immunohistochemistry. In addition, the DYSF gene of the patient and his parents was sequenced and analyzed and two heterozygous mutations of the DYSF gene (c.4756C> T and c.5316dupC) were discovered. The first mutation correlated with MM while the second was a new mutation. The patient was diagnosed with a compound heterozygous mutation. The mutation site is a new member of pathogenic MM gene mutations.


Asunto(s)
Proteínas de la Membrana , Proteínas Musculares , Alelos , Miopatías Distales , Disferlina/genética , Humanos , Proteínas de la Membrana/genética , Proteínas Musculares/genética , Atrofia Muscular , Mutación/genética
12.
Dalton Trans ; 50(5): 1874-1886, 2021 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-33475098

RESUMEN

It is challenging to develop highly stable lanthanide luminescent sensors for detecting heavy metal ions and nitroaromatics in view of the human health and environmental security. To this end, two water stable Ln-MOFs with the chemical constitution of {[Ln(HL)]·3DMF·3H2O}n (Ln = Eu, LZG-Eu and Ln = Tb, LZG-Tb) have been developed solvothermally using a multidentate ligand (H4L) with the central phenyl backbone bisubstituted by 2,6-pyridine-dicarboxylic acid at the para-position, H4L = 1,4-bis(2',2'',6',6''-tetracarboxy-1,4':4,4''-pyridyl)benzene. Single crystal analysis demonstrates that two novel Ln-MOFs feature 4,4,4-connected nets with an unprecedented topology symbol of {42·6·83}2{42·62·82}{42·84} and contain two kinds of one-dimensional channels. Powder X-ray diffraction as well as the luminescence determination results indicate that they retain their crystallinity and structural integrity in harsh acidic and basic conditions with pH in the range of 4-11. Moreover, they are highly luminescent, which makes them excellent chemical sensors for detecting Cu2+ and 4-NP (4-nitrophenol) with high selectivity and sensitivity in aqueous media such as deionized water, tap water, and river water based on distinct quenching effects. To the best of our knowledge, their detection limits are lower than those documented so far. In addition, the quenching efficiency of 4-NP was retained in the presence of interfering ions even after the compounds were used for five cycles, which makes them attractive, reliable, visual, and recyclable luminescent Ln-MOF sensor materials for 4-NP. The recognition mechanism for Cu2+ could be attributed to the dissociation of the main framework induced by Cu2+ and the subsequent formation of a Cu2+ coordination species and that for 4-NP is considered to be multi-quenching mechanisms dominated by competition absorption.


Asunto(s)
Cobre/análisis , Elementos de la Serie de los Lantanoides/química , Sustancias Luminiscentes/química , Nitrofenoles/análisis , Agua/química , Ligandos , Modelos Moleculares , Conformación Molecular
13.
Dalton Trans ; 48(32): 12326-12335, 2019 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-31342033

RESUMEN

A monocationic ZnII tetrahedral cluster, [Zn4L3(µ3-OH)]·NO3·1.25H2O (Zn4L3) based on a new salicylamide imine ligand H2L, H2L = 1-(2-hydroxy-3-methoxy-benzamido)-3-(2-hydroxy-3-methoxy-benzylideneamino)-propane, has been prepared. Single crystal X-ray analysis reveals that three deprotonated ligands L2- chelate three Zn(ii) centres with their salicylamide moiety in such a way that the three salicylimine groups attached to the other side of the three chelates are converged to bind another Zn(ii) centre to provide a tetrahedral cluster with two phenyl groups of the same ligand L2- being close enough to present a strong intramolecular ππ stacking effect. Fluorescence studies indicate that Zn4L3 is stable in water and exhibits highly sensitive and selective recognition of phosphates against other common anions including CO32-, HCO3-, NO3-, F-, Cl-, Br-, I-, HSO4-, SO42-, OAc-, BF4-, ClO4- and CF3SO3- in HEPES buffer solution (pH = 7.4) + DMSO (V : V = 1 : 9). The excellent sensing capability of Zn4L3 for phosphate against other common anions with a low detection limit of 0.15 µM renders it a candidate probe for phosphate detection. Furthermore, the observed fluorescence quenching responses of Zn4L3 towards phosphates were highly reversible. The possible sensing mechanisms for phosphate detection by Zn4L3 was investigated by means of 1H NMR, UV-Vis spectra and high-resolution ESI-MS spectra and the results indicate that phosphates could exclusively decompose Zn4L3 to release H2L in HEPES buffer solution (pH = 7.4) + DMSO (V : V = 1 : 9).

14.
Inorg Chem ; 57(17): 10873-10880, 2018 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-30102027

RESUMEN

Five heterometallic ZnII6-LnIII3 macrocycles based on a salicylamide imine multidentate unsymmetrical ligand H2L [1-(2-hydroxy-3-methoxy-benzamido)-2-(2-hydroxy-3-methoxy-benzylideneamino)-ethane] have been prepared via a coordination-driven self-assembly strategy. Single-crystal X-ray diffraction analysis reveals that the five metallocycles are isomorphic with a formula of [Zn6Ln3L6(OH)2(NO3)4(H2O)]·3NO3· nCH3CN (ZnLn-1, where Ln = Pr, Nd, Eu, Tb, or Yb; for ZnPr-1, n = 4; for ZnNd-1, ZnEu-1, and ZnTb-1, n = 2; for ZnYb-1, n = 3), where six octadentate ligands L2- and two in situ-formed µ2-OH- ions bridged the alternating ZnII-LnIII-ZnII subunits into a macrocycle. Along with the structural novelty, ZnNd-1 shows distinctive enhanced emission in the visible and near-infrared range upon addition of OAc-. On the basis of ultraviolet-visible spectroscopy, 1H nuclear magnetic resonance, single-crystal X-ray diffraction, and high-resolution electrospray ionization mass spectrometry, we deduced that this emission enhancement could be attributed to the synergistic effect of TICT and the absent nonradiative transition of µ2-OH- induced distinctively by OAc- bridging. Our results demonstrate that the NdIII-containing heterometallic macrocycle can act as a host for anion exchanging and provide a nice example of heterometallic macrocycles with interesting properties and potential applications.

15.
Dalton Trans ; 45(19): 8154-63, 2016 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-27092471

RESUMEN

The employment of a multidentate salicylamide salen-like ligand, 2-hydroxy-N-(2-(2-hydroxybenzylidene)amino)ethyl)benzamide (H3L), in aid of NO3(-) anions under weak basic conditions in Zn(II)-Ln(III) chemistry (Ln = Eu, and Dy, ) led to the isolation of two novel butterfly heterometallic dodecanuclear clusters with six Ln(III) ions occupying the body position and six Zn(II) ions the outer wing-tip sites. All of them are fully characterized by elemental analysis, FT-IR spectroscopy, TG analysis, single-crystal X-ray diffraction, and X-ray powder diffraction (XRPD) techniques. Luminescence studies indicate that exhibits dual emission, while exhibits a bright blue emission under visible light excitation. Furthermore, magnetic susceptibility studies carried out for indicate that the magnetic exchange between Dy(III) ions revealed ferromagnetic interactions with interesting slow relaxation of magnetization of the SMM behavior.

17.
Mol Plant ; 6(3): 768-80, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23376772

RESUMEN

Tricheary elements (TEs), wrapped by secondary cell wall, play essential roles in water, mineral, and nutrient transduction. Cadmium (Cd) is a toxic heavy metal that is absorbed by roots and transported to shoot, leaves, and grains through vascular systems in plants. As rice is a major source of Cd intake, many efforts have been made to establish 'low-Cd rice'. However, no links have been found between cellulose biosynthesis and cadmium accumulation. We report here a rice brittle culm13 mutant, resulting from a novel missense mutation (E101K) [corrected] in the N-terminus of cellulose synthase subunit 9 (CESA9). Except for the abnormal mechanical strength, the mutant plants are morphologically indistinguishable from the wild-type plants. Transmission electron microscopy (TEM) and chemical analyses showed a slight reduction in secondary wall thickness and 22% decrease in cellulose content in bc13 plants. Moreover, this mutation unexpectedly confers the mutant plants Cd tolerance due to less Cd accumulation in leaves. Expression analysis of the genes required for Cd uptake and transport revealed complicated alterations after applying Cd to wild-type and bc13. The mutants were further found to have altered vascular structure. More importantly, Cd concentration in the xylem saps from the bc13 plants was significantly lower than that from the wild-type. Combining the analyses of CESA9 gene expression and Cd content retention in the cell-wall residues, we conclude that CESA9(E101K) [corrected] mutation alters cell-wall properties in the conducting tissues, which consequently affects Cd translocation efficiency that largely contributes to the low Cd accumulation in the mutant plants.


Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Cadmio/metabolismo , Cadmio/toxicidad , Pared Celular/metabolismo , Celulosa/biosíntesis , Oryza/metabolismo , Adaptación Fisiológica/genética , Secuencia de Bases , Transporte Biológico/efectos de los fármacos , Transporte Biológico/genética , Fenómenos Biomecánicos/efectos de los fármacos , Pared Celular/efectos de los fármacos , Pared Celular/ultraestructura , Clonación Molecular , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Genes de Plantas/genética , Glucosiltransferasas/genética , Datos de Secuencia Molecular , Mutación Missense/genética , Oryza/citología , Oryza/genética , Oryza/ultraestructura , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Xilema/efectos de los fármacos , Xilema/genética
18.
Chemistry ; 19(11): 3590-5, 2013 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-23417845

RESUMEN

Framework-isomeric three-dimensional (3D) Cd-Ln heterometallic metal-organic frameworks (HMOFs), {[Ln2 (ODA)6 Cd3 (H2 O)6 ]⋅6 H2 O}n (Ln=Gd (1 a) and Tb (1 b), ODA=oxydiacetic acid) and {[Cd(H2 O)6 ]⋅[Ln2 (ODA)6 Cd2 ]⋅H2 O}n (Ln=Gd (2 a), Tb (2 b)), with neutral and anionic pores, respectively, were designed based on a lanthanide metalloligand strategy and synthesized by using a stepwise assembly and a hydrothermal method. Luminescence studies revealed that 1 b and 2 b can act as luminescent metal-organic frameworks and their light-emitting properties can be modulated by small guest molecules and the manganese counterion, respectively.


Asunto(s)
Cadmio/química , Elementos de la Serie de los Lantanoides/química , Luminiscencia , Compuestos Organometálicos/síntesis química , Aniones/química , Cristalografía por Rayos X , Mediciones Luminiscentes , Modelos Moleculares , Compuestos Organometálicos/química , Estereoisomerismo
19.
Zhonghua Yi Xue Za Zhi ; 93(41): 3256-60, 2013 Nov 05.
Artículo en Chino | MEDLINE | ID: mdl-24401617

RESUMEN

OBJECTIVE: To explore the levels of adiponectin (APN), interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in first episode drug naїve schizophrenics and further examine the role of adipocytokines in schizophrenia. METHODS: Ninety-six normal weight schizophrenics and 22 overweight/obese ones from First Affiliated Hospital, Zhengzhou University and 60 healthy controls were enrolled. Serum levels of IL-1ß, IL-6, TNF-α and APN were measured with enzyme linked immunosorbent assay (ELISA). RESULTS: Serum levels of IL-1ß, IL-6 and TNF-α in normal weight schizophrenics (54 ± 13, 34 ± 12, 48 ± 18) pg/ml and overweight/obese schizophrenics (71 ± 21, 40 ± 12, 53 ± 18) pg/ml were significantly higher than those in the controls (23 ± 16, 16 ± 7, 32 ± 15) pg/ml (P < 0.05). Serum levels of IL-1ß and IL-6 in overweight/obese schizophrenics were significantly higher than those in normal weight schizophrenics (P < 0.05). Serum level of adiponectin in normal weight schizophrenics was significantly higher than that in control group [(12 ± 4) vs (9 ± 4) pg/ml, P < 0.05]. CONCLUSION: The serum levels of APN, IL-1ß, IL-6 and TNF-α increase in first episode drug naїve schizophrenics. It suggests that an inflammatory response mediated by adipocytokines. APN may play a pro-inflammatory role in schizophrenia.


Asunto(s)
Adiponectina/sangre , Interleucina-1beta/sangre , Interleucina-6/sangre , Esquizofrenia/sangre , Factor de Necrosis Tumoral alfa/sangre , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Adulto Joven
20.
Luminescence ; 27(6): 459-65, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22223563

RESUMEN

To explore the relationship between the structure of the ligands and the luminescent properties of the lanthanide complexes, luminescent lanthanide complexes of a new tripodal ligand, featuring N-thenylsalicylamide arms, were synthesized and characterized by elemental analysis, IR and TGA measurements. Photophysical properties of the complexes were studied by means of UV - visible absorption and steady-state luminescence spectroscopy. The results of UV - vis spectra indicate that metal binding does not disturb the electronic structure of the ligand. Excited-state luminescence lifetimes and quantum yields of the complexes were determined. The photoluminescence analysis suggested that there is an efficient ligand - Ln(III) energy transfer for the Tb(III) complex, and the ligand is an efficient 'antenna' for Tb(III). From a more general perspective, the results demonstrated the potential application of the lanthanide complex as luminescent materials in material chemistry.


Asunto(s)
Técnicas de Química Sintética/métodos , Elementos de la Serie de los Lantanoides/química , Luminiscencia , Transferencia de Energía , Elementos de la Serie de los Lantanoides/síntesis química , Ligandos , Estructura Molecular , Nitratos/química , Salicilamidas/química , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Terbio/química , Terbio/metabolismo
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