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1.
BMC Microbiol ; 24(1): 5, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172684

RESUMEN

BACKGROUND: Harmonia axyridis is an effective natural enemy insect to a variety of phloem-sucking pests and Lepidopteran larvae, such as aphids, scabies, and phylloxera, while its industrial production is limited due to unmature artificial diet. Insect intestinal microbiota affect host development and reproduction. The aim of this study is to understand intestinal microbiota composition of H. axyridis and screen effective probiotics on artificial diet. Considering the role of the components and composition of the diet on the structure and composition of the intestinal microbiome, four kinds of diets were set up: (1) aphid; (2) basic diet; (3) basic diet + glucose; (4) basic diet + trehalose. The gut microbiota of H. axyridis was detected after feeding on different diets. RESULTS: Results showed that the gut microbiota between artificial diet group and aphid groups were far apart, while the basic and glucose groups were clearly clustered. Besides, the glucose group and trehalose group had one unique phylum, Cryptophyta and Candidatus Saccharibacteria, respectively. The highest abundance of Proteobacteria was found in the aphid diet. The highest abundance of Firmicutes was found in the basic diet. However, the addition of glucose or trehalose alleviated the change. In addition, the relative abundance of Enterobacter, Klebsiella, Enterobacteriaceae_unclassified, Enterobacteriales_unclassified and Serratia in the aphid group was higher than other groups. Moreover, the function of gut genes in each group also showed clear differences. CONCLUSION: These results have offered a strong link between artificial diets and gut microbes, and also have provided a theoretical basis for the screening of synergistic probiotics in artificial diet.


Asunto(s)
Áfidos , Escarabajos , Microbioma Gastrointestinal , Animales , Trehalosa , Insectos , Dieta , Enterobacter , Glucosa
2.
Biochem Genet ; 61(5): 2042-2055, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36929358

RESUMEN

Streptomyces are one of the most prolific sources of bioactive and structurally diverse secondary metabolites for natural product drug discovery. Genome sequencing and bioinformatics analysis revealed that the genomes of Streptomyces harbor a wealth of cryptic secondary metabolite biosynthetic gene clusters that could encode novel compounds. In this work, a genome mining approach was employed to investigate the biosynthetic potential of Streptomyces sp. HP-A2021, isolated from rhizosphere soil of Ginkgo biloba L. The complete genome of HP-A2021 was sequenced and contained the 9,607,552 base pair linear chromosome with a GC content of 71.07%. The annotation results revealed the presence of 8534 CDSs, 76 tRNA genes, and 18 rRNA genes in HP-A2021. The highest dDDH and ANI values based on genome sequences between HP-A2021 and the most closely related type strain, Streptomyces coeruleorubidus JCM 4359, were 64.2% and 92.41%, respectively. In total, 33 secondary metabolite biosynthetic gene clusters with an average length of 105,594 bp were identified, including the putative thiotetroamide, alkylresorcinol, coelichelin, and geosmin. The antibacterial activity assay confirmed that the crude extracts of HP-A2021 showed potent antimicrobial activity against human pathogenic bacteria. Our study demonstrated that Streptomyces sp. HP-A2021 will propose a potential use in biotechnological and novel bioactive secondary metabolite biosynthetic applications.


Asunto(s)
Productos Biológicos , Streptomyces , Humanos , Genoma Bacteriano , Productos Biológicos/metabolismo , Biología Computacional , Antibacterianos/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Familia de Multigenes
3.
Inorg Chem ; 61(2): 923-930, 2022 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-34968030

RESUMEN

Cooperative assembly of the neutral cluster {Ti8O5(OEt)18L2} (L = pyrazine-2,3-dicarboxylic acid) with different metal units of Mn(NO3)2, CuCl2, Zn(OEt)2, Cd(NO3)2, Ce(NO3)3, Lu(NO3)3, and Lu(NO3)2(OEt), or the [Cu2I2] cluster, generates a family of titanium-oxygen cluster (TOC)-based coordination polymers. These one-dimensional (1D) linear structures contain the same {Ti8L2} cluster but with variable bridging metal units. The regulation of the heterometal not only affects the chain geometries of the {MTi8} but also affects the way the 1D chains are stacked in the crystal lattice. Investigation of the catalytic activities toward alcohol oxidation demonstrated the synergetic effect of combining the metal site and the photosensitive {Ti8L2} cluster in the tailored structure. Under light illumination, the {MTi8} with dual catalytic sites shows greatly enhanced catalytic activity in the selective oxidation of alcohols to aldehydes. Because the compositions and structures of {MTi8} are highly tunable, this work spotlights the potential of utilizing such metal-bridged multidimensional Ti-oxo materials for cooperative photoredox catalysis for organic transformation.

4.
Inorg Chem ; 61(6): 2903-2910, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35113567

RESUMEN

Here, we systematically studied the self-assembly behavior of chiral polyoxytitanium clusters for the first time. Through the cooperative assembly of ferrocenecarboxylic acid and ketoxime ligands, we successfully incorporated the planar chirality of ferrocene (Fc) into the layered {Ti5} building blocks. The resulting {Ti5Fc} clusters can be used as structural units to assemble into large ordered structures in various ways; either a pair of {Ti5Fc} enantiomers are bridged by organic adhesive to form sandwich structures or two homochiral {Ti5Fc} units participate in the assembly to form the large clusters. Depending on the assembly modes, the chirality of {Ti5Fc} can be transferred to large nanoclusters or disappear to form mesostructures. The difference of the assembly modes between the {Ti5Fc} units can also tune the photoelectric activity of the resulting clusters, which has been verified by using {Ti10Fc-6/7} as catalysts for photocatalytic selective sulfide oxidation. This work not only is an important breakthrough in the study of the self-assembly of chiral nanoclusters but also provides an important reference for understanding of chiral transfer on the nanoscale.

5.
Inorg Chem ; 61(26): 10151-10158, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35748673

RESUMEN

Incorporating heterometal into titanium-oxygen clusters (TOCs) is an effective way to improve its catalytic activity. Herein, we synthesize three novel heterometallic TOCs with the formula of [Ti6Cu2O7(Dmg)2(OAc)4(iPrO)6][H2Ti6Cu2O7(Dmg)2(OAc)4(iPrO)8] ({Ti6Cu2}), [Ti8Cu2O9(Dmg)2(OAc)2(iPrO)12] ({Ti8Cu2}), and [Ti10Co2O6(Dmg)2(Pdc)4(iPrO)18Cl3] ({Ti10Co2}, DmgH2 = dimethylglyoxime; PdcH2 = pyridine-2,3-dicarboxylic acid) using dimethylglyoxime and different carboxylates as the synergistic ligands. By depositing the clusters {Ti6Cu2} and {Ti10Co2} on carbon cloth as electrodes, we investigated the electrocatalytic performance of TOCs for full water splitting for the first time. To reach a 10 mA cm-2 current density in an alkaline solution, the {Ti10Co2}@CC electrode needs an overpotential as low as 120 and 400 mV for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), respectively. In addition, full water-splitting equipment with {Ti10Co2}@CC as a cathode and an anode need only 1.67 V to deliver a current density of 10 mA cm-2. Our work confirmed the potential of noble metal-free TOCs as bifunctional cluster-based electrocatalysts for water splitting, and their activities can be tuned by doping with different metal ions.

6.
Inorg Chem ; 60(6): 3980-3987, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33626279

RESUMEN

Four new tris-Anderson polyoxometalates (POMs), (NH4)4[ZnMo6O18(C4H8NO3)(OH)3]·4H2O (1), (NH4)4[CuMo6O18(C4H8NO3)(OH)3]·4H2O (2), (TBA)3(NH4)[ZnMo6O17(C5H9O3)2(OH)]·10H2O (3) (TBA = n-C16H36N), and (NH4)4[CuMo6O18(C5H9O3)2]·16H2O (4), were synthesized by a microwave-assisted method. Single-crystal X-ray diffraction revealed that 1 and 2 contained a tris (trihydroxyl organic compounds) ligand grafted on one side, while two tris ligands were grafted on two sides to form χ/δ and δ/δ isomers in 3 and 4, respectively. 1H and 13C NMR spectra of the χ/δ isomer 3 were obtained for the first time, with six methylenes showing six peaks in the 1H NMR spectrum and only four peaks in the 13C NMR spectrum. Mass spectrometry monitoring revealed that during the microwave-assistant process the tris ligand can graft onto POMs to form 1, while tris directly coordinates with metallic heteroatoms to form isopolymolybdates during the conventional reflux synthesis process. In addition, 1-4 can catalyze CO2 with epoxides into cyclic carbonates with high selectivity and yields at an atmospheric pressure of CO2, which is lower than the pressure of CO2 in other catalysis using POMs as catalysts. Furthermore, 1-4 showed good catalytic stability and cycling properties. Mechanism studies substantiated POMs cocatalyzed with Br- to improve the catalytic yields.

7.
Inorg Chem ; 59(11): 7512-7519, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32394703

RESUMEN

With use of a macrocyclic polyphenol, tert-butylcalix[8]arene (TBC[8]), as ligands, a series of TBC[8]-stabilized {Ti4O2}clusters, containing penta- and hexacoordinated Ti centers, were synthesized. Such complexes are "core-shell" shaped containing a {Ti4O2} core arranged in a zigzag fashion. While outer walls of the clusters are decorated by deprotonated TBC[8], their upper and lower surfaces can be modified by various O- or N-donor ligands, and the ratio of the penta- and hexacoordinated Ti(IV) centers in the {Ti4O2} core can be precisely regulated from 4:0, to 3:1, to 2:2, to 1:3, and finally to 0:4. The combined coordination of different ligands in the axial direction shows significant influence on the adsorption of the TBC[8]-Ti4 system in the visible-light region, and their absorption edge can be precisely regulated from 600 to 700 nm. The above structural functionalization in the TBC[8]-Ti4 system also tunes their photocatalytic H2 production activities and oxidative desulfurization ability. Thus, for the first time, by confining the polyoxotitanium cluster in macrocyclic molecules, we provide an example of understanding the structure-property relationship of titanium-oxygen materials by ligand modification.

8.
Inorg Chem ; 58(21): 14876-14884, 2019 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-31637917

RESUMEN

A series of functional cation-regulated isopolymolybdate-based organic-inorganic hybrid compounds, Na2H2[Mo4O12(C8H17O5N)2]·10H2O (1), Na2[M(Bis-tris)(H2O)]2[Mo7O24]·10H2O [M = Cu, 2; Ni, 3; Co, 4; Zn, 5; Bis-tris = 2,2-Bis(hydroxymethyl)-2,2',2″-nitrilotriethanol], and (NH4)2[M(Bis-tris)(H2O)]2[Mo7O24]·6H2O (M = Zn, 6; Cu, 7), were synthesized and characterized toward advanced molecular catalyst design. Compound 1 is a covalently bonded adduct, and its self-assembly process can be probed by electrospray ionization mass spectrometry (ESI-MS). Compounds 2-7 are polyoxometalate (POM)-based hybrids containing classic heptamolybdate anions and complex cations with Bis-tris ligands. All of these compounds showed remarkable catalytic effects for selective sulfide oxidation. To the best of our knowledge, compound 5 presents the best catalytic activity so far among the reported hybrid materials with common easily synthesized small-molecule POM clusters and also exhibits outstanding reliability. The conclusion of the catalytic effect is drawn from the results that Zn-based compounds have better catalytic effects than other transition-metal-containing compounds and the compound constructed by Na+ has higher catalytic activity than that constructed by NH4+. The mechanism studies show that the improvements of the catalytic performance are caused by the synergy between classic heptamolybdate anions and complex cations. ESI-MS data and UV-vis spectra revealed that the POM anions can form intermediate peroxomolybdenum units during catalytic reaction. Further, the combination of the substrate thioanisole with complex cations was characterized by NMR experiments and UV-vis spectra. Thus, a new synergistic mechanism of anions and cations is proposed in which the activated thioanisole is used as a nucleophile to attack the peroxomolybdenum bonds, and this provides a new strategy in the design of reliable POM-based catalysts.

9.
Inorg Chem ; 57(8): 4234-4238, 2018 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-29608055

RESUMEN

A new nanosized polyoxometalate modified by benzylarsonate ligands, [(C7H7AsO3)6W12O36]12- (1a), was successfully isolated and structurally characterized as Na2(C2H8N)4H6[(C7H7AsO3)6W12O36]·30H2O (1). Controlled protonation of 1a led it to self-reorganize into isomer cage cluster [(C7H7AsO3)6W12O30(OH)4(H2O)2]4- (2a) with an organic ligand arranging in "half-open" mode. The reversibly switchable cage transform was monitored by 1H NMR. Also, the origin of the solid supramolecular chirality in the crystal 1 and the aggregation process of 1a were preliminarily studied.

10.
Small ; 13(40)2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28863240

RESUMEN

Silk fibroin (SF) offers great opportunities in manufacturing biocompatible/partially biodegradable devices with environmental benignity and biomedical applications. To obtain active SF devices of next generation, this work is to demonstrate a new functionalization strategy of the mesoscopic functionalization for soft materials. Unlike the atomic functionalization of solid materials, the meso-functionalization is to incorporate meso-dopants, i.e., functional molecules or nanomaterials, quantum dots, into the mesoscopic networks of soft materials. In this work, wool keratin (WK) molecules were adopted as mediating molecules to incorporate gold nanoclusters (AuNCs), into the mesoscopic networks of SF. It follows from our analyses that the ß-crystallites between WK and SF molecules establish the binding between WK@AuNCs and the SF networks. The incorporated WK@AuNCs are electron rich and serve as electronically charged nano particles to bridge the growth of Ag filaments in bio-degradable WK@AuNCs-SF memristors. The meso-functionalization can greatly enhance the performance of SF materials and endows them with new functionalities. This can be highlighted by biocompatible/partly degradable WK@AuNCs functionalized SF resistive random-access memories, having the enhanced resistive switching memory performance, and the unique synapse characteristics and the capability of synapse learning compared with neat SF devices, and of great importance in nonvolatile memory, analog circuits, and neuromorphic applications.


Asunto(s)
Fibroínas/química , Oro/química , Queratinas/química , Nanopartículas del Metal/química , Seda/química
11.
Beijing Da Xue Xue Bao Yi Xue Ban ; 48(1): 16-22, 2016 Feb 18.
Artículo en Zh | MEDLINE | ID: mdl-26885903

RESUMEN

OBJECTIVE: To determine the expression profile and potential roles of CD24 in oral squamous cell carcinoma and explore the values of CD24 function as a potential target of clinical therapy. METHODS: Semi-quantitative immunohistochemistry was used to construct the expression profile of CD24 in 78 human oral tissues and 59 Hamster buccal pouch tissues. Real-time RT-PCR and Western blot were used to analyze the CD24 expression levels in oral DOK4 cells, oral cancer CAL-27 and WSU-HN6 cells. Then these two cancer cell lines were selected to evaluate the effect of all-trans retinoic acid (ATRA) and CD24 antibody on CD24 expression, and the proliferation and tumorsphere formation capacity of these two cell lines. RESULTS: CD24 expression was found significantly elevated in both human and animal tissues compared with normal and benign tissues (P<0.05), as well as in oral cancer CAL-27 and WSU-HN6 cells compared with DOK cells (P<0.05). CAL-27 and WSU-HN6 cells possess increased proliferative and specific tumorsphere formation capability compared with DOK cells (P<0.05). Both ATRA and CD24 antibody were able to effectively inhibit the proliferation and tumorsphere formation of CAL-27 and WSU-HN6 cells (P<0.05). Among them ATRA at least involved partially in the proliferation by down-regulating the CD24 expression (P<0.05), while CD24 antibody blocking had no effect on the CD24 expression. CONCLUSION: CD24 was upregulated in oral cancer and functioned as a potential factor that promoted the proliferation and tumorsphere formation of CAL-27 and WSU-HN6 cells. Both ATRA and CD24 antibody might effectively inhibit the proliferation and tumorsphere formation of CAL-27 and WSU-HN6 cells and function as a potential therapy target.


Asunto(s)
Antígeno CD24/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias de la Boca/metabolismo , Animales , Línea Celular Tumoral , Cricetinae , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Mucosa Bucal/metabolismo , Tretinoina/farmacología
12.
Chem Sci ; 15(20): 7643-7650, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38784741

RESUMEN

Attaining meticulous dominion over the binding milieu of catalytic metal sites remains an indispensable pursuit to tailor product selectivity and elevate catalytic activity. By harnessing the distinctive attributes of a Zr4+-anchored thiacalix[4]arene (TC4A) metalloligand, we have pioneered a methodology for incorporating catalytic Ag1+ sites, resulting in the first Zr-Ag bimetallic cluster, Zr2Ag7, which unveils a dualistic configuration embodying twin {ZrAg3(TC4A)2} substructures linked by an {AgSal} moiety. This cluster unveils a trinity of discrete Ag sites: a pair ensconced within {ZrAg3(TC4A)2} subunits and one located between two units. Expanding the purview, we have also crafted ZrAg3 and Zr2Ag2 clusters, meticulously mimicking the two Ag site environment inherent in the {ZrAg3(TC4A)2} monomer. The distinct structural profiles of Zr2Ag7, ZrAg3, and Zr2Ag provide an exquisite foundation for a precise comparative appraisal of catalytic prowess across three Ag sites intrinsic to Zr2Ag7. Remarkably, Zr2Ag7 eclipses its counterparts in the electroreduction of CO2, culminating in a CO faradaic efficiency (FECO) of 90.23% at -0.9 V. This achievement markedly surpasses the performance metrics of ZrAg3 (FECO: 55.45% at -1.0 V) and Zr2Ag2 (FECO: 13.09% at -1.0 V). Utilizing in situ ATR-FTIR, we can observe reaction intermediates on the Ag sites. To unveil underlying mechanisms, we employ density functional theory (DFT) calculations to determine changes in free energy accompanying each elementary step throughout the conversion of CO2 to CO. Our findings reveal the exceptional proficiency of the bridged-Ag site that interconnects paired {ZrAg3(TC4A)2} units, skillfully stabilizing *COOH intermediates, surpassing the stabilization efficacy of the other Ag sites located elsewhere. The invaluable insights gleaned from this pioneering endeavor lay a novel course for the design of exceptionally efficient catalysts tailored for CO2 reduction reactions, emphatically underscoring novel vistas this research unshrouds.

13.
Cancer ; 119(3): 563-74, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-22833444

RESUMEN

BACKGROUND: The active metabolite of vitamin D 1α,25-dihydroxycholecalciferol (1,25D(3) ) has exhibited broad-spectrum antitumor activity in xenograft animal models. However, its activity against metastatic disease has not been extensively investigated. METHODS: Squamous cell carcinoma (SCC) or 1,25D(3) -resistant variant SCC-DR cells were treated with 1,25D(3) . Actin organization was examined by immunofluorescence assay. Cell migration was assessed by "wound" healing and chemotactic migration assays. Cell invasion was assessed by a Matrigel-based invasion assay and in situ zymography. Matrix metalloproteinase 2 (MMP-2) and MMP-9 expression and secretion were examined by immunoblot analysis and an enzyme-linked immunosorbent assay, respectively. E-cadherin expression was assessed by flow cytometry, immunoblot analysis, and immunohistochemistry. Knockdown of E-cadherin was achieved by small interfering RNA. An experimental metastasis mouse model was created by intravenous injection of tumor cells; and lung tumor development in the mice was assessed by magnetic resonance imaging, gross observation, and histology. RESULTS: SCC cellular morphology and actin organization were altered by 10 nM 1,25D(3) . 1,25D(3) inhibited SCC cell motility and invasion, which were associated with reduced expression and secretion of MMP-2 and MMP-9, and 1,25D(3) promoted the expression of E-cadherin. These findings were not observed in SCC-DR cells. Knock down of E-cadherin rescued 1,25D(3) -inhibited cell migration. Intravenous injection of SCC or SCC-DR cells resulted in the establishment of extensive pulmonary lesions in saline-treated C3H mice. Treatment with 1,25D(3) resulted in a marked reduction in the formation of lung tumor colonies in mice that were injected with SCC cells, but not in mice that were injected with SCC-DR cells. CONCLUSIONS: 1,25D(3) suppressed SCC cell motility, invasion, and metastasis, partially through the promotion of E-cadherin-mediated cell-cell adhesion.


Asunto(s)
Calcitriol/farmacología , Carcinoma de Células Escamosas/patología , Movimiento Celular/efectos de los fármacos , Neoplasias Pulmonares/patología , Animales , Cadherinas/genética , Cadherinas/metabolismo , Carcinoma de Células Escamosas/tratamiento farmacológico , Adhesión Celular/efectos de los fármacos , Adhesión Celular/genética , Línea Celular Tumoral , Forma de la Célula/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/secundario , Ratones , Ratones Endogámicos C3H , Invasividad Neoplásica , Metástasis de la Neoplasia , Trasplante de Neoplasias
14.
Dalton Trans ; 52(17): 5438-5442, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37083046

RESUMEN

Accurate manipulation of ligands at specific sites in robust clusters is attractive but difficult, especially for those ligands that coordinate in intricate binding patterns. By linking the shuttlecock-like {Cu4(µ4-Cl)TC4A} motif and the phenylphosphate (PhPO32-) ligand, we elaborately design and synthesize two Cu(II)-thiacalix[4]arene metallamacrocycles (MMCs), namely Cu12L3 and Cu16L4, which have regular triangular and quadrilateral topologies, respectively. While keeping the core intact, the Cl- and PhPO32- in those two MMCs, which coordinated in a µ4-bridging fashion, can be accurately substituted with salicylate ligands. Theoretical calculations have been carried out to reveal the effect of ligand tailoring on the electronic structure of clusters. Structural regulation can affect the catalytic activity of these clusters, which has been verified by using the clusters as catalysts for selective sulfide oxidation.

15.
Chem Sci ; 14(48): 14280-14289, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38098712

RESUMEN

Skillfully engineering surface ligands at specific sites within robust clusters presents both a formidable challenge and a captivating opportunity. Herein we unveil an unprecedented titanium-oxo cluster: a calix[8]arene-stabilized metallamacrocycle (Ti16L4), uniquely crafted through the fusion of four "core-shell" {Ti4@(TBC[8])(L)} subunits with four oxalate moieties. Notably, this cluster showcases an exceptional level of chemical stability, retaining its crystalline integrity even when immersed in highly concentrated acid (1 M HNO3) and alkali (20 M NaOH). The macrocycle's surface unveils four specific, customizable µ2-bridging sites, primed to accommodate diverse carboxylate ligands. This adaptability is highlighted through deliberate modifications achieved by alternating crystal soaking in alkali and carboxylic acid solutions. Furthermore, Ti16L4 macrocycles autonomously self-assemble into one-dimensional nanotubes, which subsequently organize into three distinct solid phases, contingent upon the specific nature of the four µ2-bridging ligands. Notably, the Ti16L4 exhibit a remarkable capacity for photocatalytic activity in selectively reducing CO2 to CO. Exploiting the macrocycle's modifiable shell yields a significant boost in performance, achieving an exceptional maximum CO release rate of 4.047 ± 0.243 mmol g-1 h-1. This study serves as a striking testament to the latent potential of precision-guided surface ligand manipulation within robust clusters, while also underpinning a platform for producing microporous materials endowed with a myriad of surface functionalities.

16.
Dalton Trans ; 52(21): 7071-7078, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37161840

RESUMEN

In the field of metallo-supramolecular assemblies, supramolecular macrocycles have attracted considerable attention due to their guest recognition and catalytic properties. Herein, we report a novel strategy for the construction of giant hollow macrocyclic structures using a bi-directional geometric constraint strategy. We investigated the structural design of two terpyridine-based tetratopic organic ligands, whose inner and outer rims have different angles. Compared to conventional strategies of self-assembly using single angular orientation building blocks that typically generate small macrocyclic objects or polymers, the mutual interaction between the different angles of the ligands could promote the formation of giant hollow macrocyclic supramolecular architectures. The self-assembly mechanism and hierarchical self-assembly of giant supramolecular macrocycles have been characterized by NMR, ESI-MS and TEM experiments. The strategy used in this study not only advances the design of giant 2D macrocycles with large inner diameters but also gives insights into the mechanism of formation of large structures.

17.
World J Gastroenterol ; 28(18): 1981-1995, 2022 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-35664967

RESUMEN

BACKGROUND: Fusobacterium nucleatum (F. nucleatum) has long been known to cause opportunistic infections and has recently been implicated in colorectal cancer (CRC), which has attracted broad attention. However, the mechanism by which it is involved in CRC development is not fully understood. AIM: To explore its potential causative role in CRC development, we evaluated the colon pathology, mucosa barrier, colon microbiota and host transcriptome profile after F. nucleatum infection in an azoxymethane/dextran sulfate sodium salt (AOM/DSS) mouse model. METHODS: Three groups of mice were compared to reveal the differences, i.e., the control, AOM/DSS-induced CRC and AOM/DSS-FUSO infection groups. RESULTS: Both the AOM/DSS and AOM/DSS-FUSO groups exhibited a significantly reduced body weight and increased tumor numbers than the control group, and AOM/DSS mice with F. nucleatum infection showed the highest tumor formation ratio among the three groups. Moreover, the colon pathology was the most serious in the AOM/DSS-FUSO group. We found that the structure of the colon microbiota changed considerably after F. nucleatum infection; striking differences in mucosal microbial population patterns were observed between the AOM/DSS-FUSO and AOM/DSS groups, and inflammation-inducing bacteria were enriched in the mucosal microbiota in the AOM/DSS-FUSO group. By comparing intestinal transcriptomics data from AOM vs AOM/DSS-FUSO mice, we showed that transcriptional activity was strongly affected by dysbiosis of the gut microbiota. The most microbiota-sensitive genes were oncogenes in the intestine, and the cyclic adenosine monophosphate signaling pathway, neuroactive ligand-receptor interaction, PPAR signaling pathway, retinol metabolism, mineral absorption and drug metabolism were highly enriched in the AOM/DSS-FUSO group. Additionally, we showed that microbial dysbiosis driven by F. nucleatum infection enriched eight taxa belonging to Proteobacteria, which correlates with increased expression of oncogenic genes. CONCLUSION: Our study demonstrated that F. nucleatum infection altered the colon mucosal microbiota by enriching pathogens related to the development of CRC, providing new insights into the role of F. nucleatum in the oncogenic microbial environment of the colon.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Infecciones por Fusobacterium , Microbioma Gastrointestinal , Animales , Azoximetano/toxicidad , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/complicaciones , Neoplasias del Colon/genética , Neoplasias Colorrectales/inducido químicamente , Neoplasias Colorrectales/genética , Sulfato de Dextran , Modelos Animales de Enfermedad , Disbiosis/complicaciones , Infecciones por Fusobacterium/complicaciones , Fusobacterium nucleatum , Humanos , Mucosa Intestinal/patología , Ratones , Transcriptoma
18.
Chem Commun (Camb) ; 58(40): 6028-6031, 2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35502757

RESUMEN

Polyhedral metallocalixarene nanocage clusters based on pure Ti(IV) ions are to our knowledge unknown hitherto. Herein we report the first Ti(IV)-based metallocalixarene nanocage cluster by assembling a [Ti13O14] cage with six t-butylcalix[4]arene molecules. Notably, the cluster exhibits extraordinary stability in high-concentration acid/alkali solutions and can act as a stable photocatalyst to catalyze the oxidation of ammonia to imines.

19.
Beijing Da Xue Xue Bao Yi Xue Ban ; 43(4): 496-9, 2011 Aug 18.
Artículo en Zh | MEDLINE | ID: mdl-21844952

RESUMEN

OBJECTIVE: To investigate the expression of glycoprotein non-metastatic melanoma protein B (GPNMB) in prostate cancer and its clinical significance. METHODS: The expression of GPNMB was analysed in 63 prostate cancer and 3 heterosexual hyperplasia prostate tissue and 8 benign prostatic hyperplasia samples by immunohistochemical staining, with integral optical density(IOD) value representing expression level of positive cells. RESULTS: The expression of GPNMB was lower in benign prostatic hyperplasia (BPH, IOD=70 017.49) than in Atypical hyperplasia (IOD=101 547.33, P=0.000 1) . The expression of GPNMB in tumor (IOD= 162 027.54) was higher than in non-tumor group (IOD=79 290.97), which included BPH and atypical hyperplasia (P=0.000 1). But GPNMB expression level was not positively elevated with degree of malignancy of prostate cancer. However, the expression of GPNMB in low pathological grading(IOD=177 944.30) was higher than that in high pathological grading(IOD=150 885.81, P=0.013). CONCLUSION: The abnormal expression of GPNMB may play an important role in the development of prostate cancer and its detection may be useful for the early diagnosis of prostate cancer.


Asunto(s)
Glicoproteínas de Membrana/metabolismo , Neoplasias de la Próstata/metabolismo , Biomarcadores de Tumor/metabolismo , Humanos , Masculino , Próstata/metabolismo , Próstata/patología , Hiperplasia Prostática/metabolismo , Neoplasias de la Próstata/patología
20.
Zhonghua Yi Xue Za Zhi ; 91(37): 2648-52, 2011 Oct 11.
Artículo en Zh | MEDLINE | ID: mdl-22321934

RESUMEN

OBJECTIVE: To explore the effects of receptor interacting protein (RIP) 140 gene overexpression upon the in vitro proliferation, apoptosis, invasion and migration of microglioma cells. METHODS: The BV-2 RIP140 overexpression model (BV-2-1) was constructed by Lipofection and G418 selection, then validated by real-time PCR and Western blotting. The proliferation, apoptosis, invasion and migration potencies were compared between BV-2-1 and its parents by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay, flow cytometry and Transwell chamber. RESULTS: The BV-2-1 model was successfully constructed. Compared to those of the BV-2 group, the RIP140 mRNA and protein expression levels of BV-2-1 were markedly higher than those of the BV-2 group (t = 49.794, P < 0.01). MTT assay showed that the absorbance values in the BV-2 group were 1.157 ± 0.013, 1.679 ± 0.005 and 2.609 ± 0.008 at 24, 48, and 72 hours respectively. And those were 0.929 ± 0.013, 1.188 ± 0.008 and 1.528 ± 0.012 in the BV-2-1 group respectively. The proliferation at the time points of 48 and 72 hours of the BV-2-1 group were significantly lower than that of the BV-2 group (t = 6.058 and 9.245, both P < 0.01). Annexin-V staining showed that there were significant differences in the apoptosis rates between the BV-2 and BV-2-1 cells [(5.35 ± 0.23)% vs (3.46 ± 0.45)%, t = 6.619, P = 0.003)]. Transwell assay showed that the invaded cell number of the BV-2-1 group was 166 ± 43. And it was obviously higher than that of the BV-2 group (93 ± 32, t = 3.403, P = 0.007). Transwell assay also showed that the migrated cell number of BV-2 cells was 101 ± 25. And the migration potency of the BV-2-1 group (202 ± 50) was significantly stronger than that of the BV-2 group (t = 4.104, P = 0.002). CONCLUSION: RIP140 effectively inhibits the proliferation and facilitates the apoptosis of microglioma cells. And it may effectively facilitate the in vitro invasion and migration of microglioma cells.


Asunto(s)
Apoptosis , Neuroglía/citología , Neuroglía/metabolismo , Co-Represor 1 de Receptor Nuclear/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Ratones , Co-Represor 1 de Receptor Nuclear/genética
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