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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.
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
5.
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.

6.
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
7.
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.

8.
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
9.
Zhonghua Yi Xue Za Zhi ; 93(41): 3256-60, 2013 Nov 05.
Artículo en Zh | 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
10.
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.

11.
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.

12.
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.

13.
Plasmid ; 67(1): 60-6, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21907733

RESUMEN

Hepatocyte nuclear factor-4alpha (HNF-4a) is an important transcription factor in the liver, and regulates a large number of genes involved in many aspects of hepatocyte functions. In this study, a liver-specific transcriptional regulatory element comprised of albumin promoter (ALBp) and alpha-fetoprotein enhancer (AFPe) was obtained and cloned into the plasmid pHNF4sh-CMV(short hairpin RNA targeting HNF4α) with original CMV promoter removed, resulting to pHNF4sh-EP for liver-specific knockdown of HNF4α expression. In an attempt to verify its characteristics, pHNF4sh-EP was transfected to L02, HepG2, and COS1 cell lines in vitro and delivered into mice in vivo. pHNF4sh-CMV and pNCsh-EP were used as controls. For in vitro, the level of HNF4α mRNA and protein was decreased in all cell lines transfected with pHNF4sh-CMV whereas HNF4α mRNA and protein decreasing was only observed in L02 and HepG2 cell lines upon transfection with pHNF4sh-EP, and this decreasing was more significant as compared with pHNF4sh-CMV transfected cells. For in vivo, the decreasing of HNF4α mRNA and protein was observed in both liver and kidney tissues upon transfection with pHNF4sh-CMV. After transfection with pHNF4sh-EP, decreasing of HNF4α mRNA and protein was only found in liver tissue and this decreasing was more significant. No obvious HNF4α mRNA and protein decreasing was detected either in vitro or in vivo after transfected with pNCsh-EP. In conclusion, pHNF4sh-EP could highly-active and liver-specific knockdown of HNF4α expression liver and it will be useful for further study of the funcitions of HNF4α in liver.


Asunto(s)
Albúminas/genética , Elementos de Facilitación Genéticos/genética , Vectores Genéticos/genética , Factor Nuclear 4 del Hepatocito/metabolismo , Hígado/metabolismo , Regiones Promotoras Genéticas/genética , alfa-Fetoproteínas/genética , Animales , Western Blotting , Células COS , Chlorocebus aethiops , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Factor Nuclear 4 del Hepatocito/antagonistas & inhibidores , Factor Nuclear 4 del Hepatocito/genética , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
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
15.
Zhonghua Yi Xue Za Zhi ; 92(45): 3194-8, 2012 Dec 04.
Artículo en Zh | MEDLINE | ID: mdl-23328465

RESUMEN

OBJECTIVE: To explore the changes in serum protein levels of schizophrenics before and after treatment of risperidone and identify the potential markers of diagnosis, treatment and drug side effects of schizophrenia. METHODS: Eighty first-episode schizophrenics without other concurrent diseases and with positive and negative symptom scale (PANSS) score greater than or equal to 60 were recruited. And 15 of them were measured by proteomics. Different serum levels of proteins were obtained from these patients and were separated by two-dimensional electrophoresis (2-DE) before and after a single risperidone treatment for 8 weeks. These proteins were then identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and peptide mass fingerprinting. Enzyme-linked immunosorbent assay (ELISA) was used to verify the results. RESULTS: Almost 1400 spots were detected by 2-DE in each gel. Of these proteins, 23 protein spots showed significant differences in abundance before and after risperidone treatment. After MALDI-TOF peptide mass fingerprinting, 9 up-regulated proteins and 8 down-regulated proteins were validated after treatment. Of these proteins, the schizophrenics showed a significantly higher content of apolipoprotein A-1 (APOA-1) than those before treatment and haptoglobin (HP) protein was down-regulated after treatment. The results of ELISA were parallel with those of proteomic (P < 0.01). CONCLUSION: The serum proteins correlated with blood glucose and lipid metabolism are altered in schizophrenia after treatment of risperidone. A clinician should monitor the side effects of antipsychotic drugs according to the changes of serum proteins.


Asunto(s)
Proteómica , Risperidona/uso terapéutico , Esquizofrenia/sangre , Adolescente , Adulto , Femenino , Humanos , Masculino , Esquizofrenia/tratamiento farmacológico , Adulto Joven
16.
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
17.
Plasmid ; 65(2): 125-31, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21108965

RESUMEN

In an attempt to construct a highly active, liver-specific transcriptional regulatory element, the mouse albumin promoter (ALBp) and α-fetoprotein enhancer (AFPe) were obtained. To verify its hepatic specificity and activity, the AFPe-ALBp-containing fragment was cloned into the plasmids, pVAX-S and pGL3-Luc with original promoter removed. Plasmid pVAX-AFPe-ALBp-S was then transfected into hepatic and non-hepatic cells in vitro, and delivered into mouse by intravenous injection and intramuscular injection, respectively. In addition, pGL3-AFPe-ALBp-Luc was transfected into hepatic and non-hepatic cell lines; pVAX1, pVAX1/S, and pGL3-ALBp-Luc were used as controls. The expression of hepatitis B surface antigen (HBsAg) was observed, and luciferase activity in cells was measured. For plasmid pVAX-AFPe-ALBp-S, the expression of HBsAg was observed in hepatic cell lines, but not in a non-hepatic cell line. Using pVAX-S, the expression of HBsAg was observed in both hepatic and non-hepatic cell lines. In cells expressing pGL3-AFPe-ALBp-Luc, the level of luciferase activity was significantly higher in hepatic cell lines, compared with the non-hepatic cell lines. In addition, the level of luciferase activity in cells expressing pGL3-AFPe-ALBp-Luc was significantly higher than that of pGL3-ALBp-Luc in hepatic cell lines, suggesting that AFPe could enhance target gene expression under the control of ALBp. The expression of HBsAg was detected in mouse liver, but not muscle when using pVAX-AFPe-ALBp-S. In contrast, the expression of HBsAg was detected in both mouse liver and muscle upon transfection with pVAX-S. In conclusion, the AFPe-ALBp element could be used as a tool to induce liver-specific expression of a target gene.


Asunto(s)
Albúminas/genética , Elementos de Facilitación Genéticos/genética , Vectores Genéticos/genética , Regiones Promotoras Genéticas/genética , alfa-Fetoproteínas/genética , Animales , Células COS , Línea Celular , Chlorocebus aethiops , Regulación Neoplásica de la Expresión Génica , Orden Génico , Células HEK293 , Células HeLa , Células Hep G2 , Antígenos de Superficie de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/metabolismo , Humanos , Hígado/metabolismo , Hígado/patología , Masculino , Ratones , Ratones Endogámicos BALB C
18.
Zhonghua Yi Xue Za Zhi ; 91(7): 485-90, 2011 Feb 22.
Artículo en Zh | MEDLINE | ID: mdl-21418982

RESUMEN

OBJECTIVE: To explore the correlation between the elevated expression of cytokines under the induction of Poly(I:C) (polycytidylic acid) in maternal hosts and the abnormal behaviors of adult offsprings and understand the intervening effects of nuclear factor NF-κB inhibitor pyrrolidinedithiocarbamate (PDTC). METHODS: Poly(I:C) or saline was administered to model the maternal infection during early pregnancy in rats. And the expression of cytokines was blocked with PDTC. The maternal levels of tumor necrosis factor alpha and interleukin-10 were determined by ELISA (enzyme-linked immunosorbent assay). The adult offsprings on different treatments were then compared with regards to prepulse inhibition (PPI), passive avoidance and active avoidance. RESULTS: After the administration of Poly(I:C), there was an elevated levels of serum cytokines as shown by the markedly increased serum levels of IL-10 and TNF-α. The serum levels of IL-10 and TNF-α in the model group were significantly higher than those in the control group [(18.26 ± 1.52) pg/ml, (119.64 ± 16.42) pg/ml vs. (0.16 ± 0.13) pg/ml and (11.21 ± 1.81) pg/ml]. The elevation was partly blocked by PDTC. The serum levels of IL-10 and TNF-α in the intervention group [(12.64 ± 2.04) pg/ml and (30.34 ± 2.19) pg/ml respectively] were lower than those in the model group, but still higher than those in the control group. The psychotic-like phenotypes including defects in PPI, passive avoidance and active avoidance were observed in Poly(I:C)-treated offsprings. Such an effect was blunted by the PDTC intervention. The PPI results demonstrated that the PP2 and PP8 difference between rats in 3 groups were statistically significant, with a lower PPI value in the model group than in the intervention group, in the intervention group than in the control group and much lower in the model group than in the control group. PP4 was lower in the model group than that in the intervention group, and also lower in the model group than in the control group. There was no significant difference between the control group and the intervention group. The passive avoidance results indicated that T1 was higher in the model group than in the control and intervention groups and there was no statistical difference between the control and intervention groups. T2 was lower in the model group than in the control and intervention groups and there was no statistical difference between the control and intervention groups. And the active avoidance test results showed that total conditioned reflex times of the control group was higher than those of the intervention and model groups. No statistical difference was found between the intervention and model groups. Total reflex rate of the control group was higher than that of the intervention and model groups. No statistical difference was found between the intervention and model groups. CONCLUSION: PDTC can interfere with neural developmental disorder of adult offsprings through blunting the cytokine-mediated maternal immune response.


Asunto(s)
Reacción de Prevención/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Poli I-C/efectos adversos , Efectos Tardíos de la Exposición Prenatal , Pirrolidinas/farmacología , Tiocarbamatos/farmacología , Animales , Modelos Animales de Enfermedad , Femenino , Inhibición Psicológica , Interleucina-10/sangre , Exposición Materna , FN-kappa B/antagonistas & inhibidores , Embarazo , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/sangre
19.
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.

20.
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
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