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1.
Sensors (Basel) ; 24(10)2024 May 13.
Article de Anglais | MEDLINE | ID: mdl-38793940

RÉSUMÉ

Mobile visible light communication (VLC) is key for integrating lighting and communication applications in the 6G era, yet there exists a notable gap in experimental research on mobile VLC. In this study, we introduce a mobile VLC system and investigate the impact of mobility speed on communication performance. Leveraging a laser-based light transmitter with a wide coverage, we enable a light fidelity (LiFi) system with a mobile receiving end. The system is capable of supporting distances from 1 m to 4 m without a lens and could maintain a transmission rate of 500 Mbps. The transmission is stable at distances of 1 m and 2 m, but an increase in distance and speed introduces interference to the system, leading to a rise in the Bit Error Rate (BER). The mobile VLC experimental system provides a viable solution to the issue of mobile access in the integration of lighting and communication applications, establishing a solid practical foundation for future research.

2.
Ecotoxicol Environ Saf ; 276: 116291, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38581910

RÉSUMÉ

Myzus persicae is an important pest that has developed resistance to nearly all currently used insecticidal products. The employment of insecticide synergists is one of the effective strategies that need to be developed for the management of this resistance. Our study showed that treatment with a combination of the antibiotic, rifampicin, with imidacloprid, cyantraniliprole, or clothianidin significantly increased their toxicities against M. persicae, by 2.72, 3.59, and 2.41 folds, respectively. Rifampicin treatment led to a noteworthy reduction in the activities of multifunctional oxidases (by 32.64%) and esterases (by 23.80%), along with a decrease in the expression of the CYP6CY3 gene (by 58.57%) in M. persicae. It also negatively impacted the fitness of the aphids, including weight, life span, number of offspring, and elongation of developmental duration. In addition, bioassays showed that the combination of rifampicin and a detoxification enzyme inhibitor, piperonyl butoxide, or dsRNA of CYP6CY3 further significantly improved the toxicity of imidacloprid against M. persicae, by 6.19- and 7.55-fold, respectively. The present study suggests that development of active ingredients such as rifampicin as candidate synergists, show promise to overcome metabolic resistance to insecticides in aphids.


Sujet(s)
Aphides , Guanidines , Insecticides , Néonicotinoïdes , Composés nitrés , Butoxyde de pipéronyle , Rifampicine , Thiazoles , Animaux , Rifampicine/toxicité , Rifampicine/pharmacologie , Aphides/effets des médicaments et des substances chimiques , Insecticides/toxicité , Néonicotinoïdes/toxicité , Composés nitrés/toxicité , Thiazoles/toxicité , Guanidines/toxicité , Butoxyde de pipéronyle/toxicité , Pyrazoles/toxicité , Synergie des médicaments , Résistance aux insecticides/génétique , Pesticides synergistes/toxicité , ortho-Aminobenzoates/toxicité , Esterases/métabolisme
3.
Medicine (Baltimore) ; 103(3): e36595, 2024 Jan 19.
Article de Anglais | MEDLINE | ID: mdl-38241560

RÉSUMÉ

Rheumatoid arthritis (RA) is a joint disorder and is considered an important public health concern nowadays. So, identifying novel biomarkers and treatment modalities is urgently needed to improve the health standard of RA patients. Factors involved in RA pathogenesis are genetic/epigenetic modification, environment, and lifestyle. In the case of epigenetic modification, the expression deregulation of microRNAs and the role of histone deacetylase (HDAC) in RA is an important aspect that needs to be addressed. The present study is designed to evaluate the expression pattern of microRNAs related to the HDAC family. Five microRNAs, miR-92a-3p, miR-455-3p, miR-222, miR-140, and miR-146a related to the HDAC family were selected for the present study. Real-time polymerase chain reaction was used to estimate the level of expression of the above-mentioned microRNAs in 150 patients of RA versus 150 controls. Oxidative stress level and histone deacetylation status were measured using the enzyme-linked immunosorbent assay. Statistical analysis showed significant downregulation (P < .0001) of selected microRNAs in RA patients versus controls. Significantly raised level of HDAC (P < .0001) and 8-hydroxy-2'-deoxyguanosine (P < .0001) was observed in patients versus controls. A good diagnostic potential of selected microRNAs in RA was shown by the receiver operating curve analysis. The current study showed a significant role of deregulated expression of the above-mentioned microRNAs in RA initiation and can act as an excellent diagnostic marker for this disease.


Sujet(s)
Polyarthrite rhumatoïde , microARN , Humains , microARN/génétique , microARN/métabolisme , Polyarthrite rhumatoïde/diagnostic , Marqueurs biologiques/analyse , Études rétrospectives , Risque
4.
J Agric Food Chem ; 71(46): 17733-17741, 2023 Nov 22.
Article de Anglais | MEDLINE | ID: mdl-37934932

RÉSUMÉ

The excretory organs of insects offer potential physiological targets for insect control. In this study, RNA-seq was utilized to identify a set of transporter and receptor genes enriched in the excretory organs of the brown planthopper (BPH), Nilaparvata lugens, which is considered the most important phloem-feeding insect pest in rice. A total of 1565 and 1084 transcripts were upregulated in the excretory organs, Malpighian tubules, and hindgut, respectively, compared to the midgut, which was enriched for transport activity and oxidoreductase activity. Eight potentially important genes were selected for the exploration of biological function, including one sodium/potassium-ATPase (NKA) subunit (ATP1A1), five aquaporins (AQPs), and two neuropeptide receptors. RNA interference (RNAi) assays showed that the knockdown of ATP1A1 and two AQP genes in BPH resulted in significant lethal phenotypes (corrected mortalities = 42.9-63.6%, 7 days after injection) and significantly reduced honeydew amounts. Our findings suggest that several genes enriched in excretory organs were important for BPH survival, which could be new insect control targets.


Sujet(s)
Hemiptera , Oryza , Animaux , Transcriptome , Interférence par ARN , Hemiptera/génétique , Oryza/génétique
5.
Pest Manag Sci ; 79(4): 1388-1398, 2023 Apr.
Article de Anglais | MEDLINE | ID: mdl-36453026

RÉSUMÉ

BACKGROUND: Recent studies have shown that symbionts are involved in regulating insecticide detoxification in insects. However, there are few studies on the relationship between the symbionts found in Myzus persicae and the mechanism underlying host detoxification of insecticides. In this study, antibiotic ampicillin treatment was used to investigate the possible relationship between symbiotic bacteria and the detoxification of insecticides in the host, M. persicae. RESULTS: Bioassays showed that ampicillin significantly reduced the susceptibilities of M. persicae to imidacloprid and cyantraniliprole. Synergistic bioassays and RNAi assays showed that the susceptibilities of M. persicae to imidacloprid and cyantraniliprole were related to metabolic detoxification enzyme activities and the expression level of the cytochrome P450 gene, CYP6CY3. Also, treatment to a combination of ampicillin and enzyme inhibitors or dsCYP6CY3 showed that the negative effect of ampicillin on the susceptibility of M. persicae was effectively inhibited bydetoxification enzyme inhibitors and dsCYP6CY3. Additionally, ampicillin treatment resulted in significant increases in the activities of multifunctional oxidases and esterases, the expression level of CYP6CY3 and fitness of M. persicae. Further, ampicillin significantly reduced the total bacterial abundance and changed symbiont diversity in M. persicae. The abundance of Pseudomonadaceae decreased significantly, while the abundance of Rhodococcus and Buchnera increased significantly. CONCLUSION: Our study showed that ampicillin enhanced the resistance levels to imidacloprid and cyantraniliprole of M. persicae, which might be related to the selective elimination of symbiotic bacteria, the upregulated activities of detoxification enzymes and the increased fitness. © 2022 Society of Chemical Industry.


Sujet(s)
Aphides , Insecticides , Animaux , Insecticides/pharmacologie , Néonicotinoïdes/pharmacologie , Composés nitrés/pharmacologie , Ampicilline/métabolisme , Ampicilline/pharmacologie , Résistance aux insecticides/génétique
6.
Medicine (Baltimore) ; 100(12): e25093, 2021 Mar 26.
Article de Anglais | MEDLINE | ID: mdl-33761671

RÉSUMÉ

ABSTRACT: Based on the Thompson classification of intervertebral discs (IVDs), we systematically analyzed gene expression differences between severely degenerated and mildly degenerated IVDs and explored the underlying molecular mechanisms using bioinformatics methods and multichip integration. We used multiomics analysis, includes mRNA microarray and methylation chips, to explore the genetic network and mechanisms of lumbar disc herniation (LDH). Subsequently, the Combat function of the R language SVA package was applied to eliminate heterogeneity between the gene expression data. And the protein-protein interaction (PPI) network, gene ontology (GO), and molecular pathways were used to constructs the mechanisms network. Consequently, we obtained 149 differentially expressed genes. Related molecular pathways are the following: ribosome activity, oxidative phosphorylation, extracellular matrix response. Besides, through PPI network analysis, genes with higher connectivity such as UBA52, RPLP0, RPL3, RPLP2, and RPL27 were also identified, suggesting that they play important regulatory roles in the complex network associated with LDH. Additionally, cg12556991 (RPL27) and cg06852319 (RPLP0) were found to be LDH-related candidate DNA methylation modification sites in the IVDs tissue of LDH patients. In conclusions, ribosome activity, oxidative phosphorylation, and extracellular matrix response may be potential molecular mechanisms underlying LDH, while hub genes involved in UBA52, RPLP0, RPL3, RPLP2, and RPL27, and candidate DNA methylation modification sites of cg12556991and cg06852319 are likely key regulators in the development of LDH.


Sujet(s)
Méthylation de l'ADN/génétique , Matrice extracellulaire/génétique , Déplacement de disque intervertébral/génétique , Phosphorylation/génétique , Protéines ribosomiques/génétique , Biologie informatique , Expression des gènes/génétique , Analyse de profil d'expression de gènes , Gene Ontology , Réseaux de régulation génique/génétique , Humains , Vertèbres lombales/métabolisme , Analyse sur microréseau , Cartes d'interactions protéiques/génétique , ARN messager/métabolisme , Protéine ribosomique L3
7.
Insects ; 11(9)2020 Sep 01.
Article de Anglais | MEDLINE | ID: mdl-32882811

RÉSUMÉ

Honeydew is a watery fluid excreted by plant sap-feeding insects. It is a waste product for the insect hosts. However, it plays important roles for other organisms, such as serving as a nutritional source for beneficial insects and bacteria, as well as elicitors and effectors modulating plant responses. In this study, shotgun LC-MS/MS analyses were used to identify the proteins in the honeydew from two important rice hemipteran pests, the brown planthopper (Nilaparvata lugens, BPH) and green rice leafhopper (Nephotettix cincticeps, GRH). A total of 277 and 210 proteins annotated to insect proteins were identified in the BPH and GRH honeydews, respectively. These included saliva proteins that may have similar functions as the saliva proteins, such as calcium-binding proteins and apolipophorin, involved in rice plant defenses. Additionally, a total of 52 and 32 Oryza proteins were identified in the BPH and GRH honeydews, respectively, some of which are involved in the plant immune system, such as Pathogen-Related Protein 10, ascorbate peroxidase, thioredoxin and glutaredoxin. Coincidently, 570 and 494 bacteria proteins were identified from the BPH and GRH honeydews, respectively, which included several well-known proteins involved in the plant immune system: elongation factor Tu, flagellin, GroEL and cold-shock proteins. The results of our study indicate that the insect honeydew is a complex fluid cocktail that contains abundant proteins from insects, plants and microbes, which may be involved in the multitrophic interactions of plants-insects-microbes.

8.
J Insect Sci ; 20(1)2020 Jan 01.
Article de Anglais | MEDLINE | ID: mdl-32061084

RÉSUMÉ

The vanilloid-type transient receptor potential (TRPV) channel is reported to be the molecular target of the commercial insecticide pymetrozine, which specifically disrupts the feeding of plant sap-sucking insects. However, the functions of TRPV channels in plant sap-sucking insects have not been fully elucidated. In the present study, RNA interference was used to investigate the effects of the knockdown of TRPV genes (Nan and Iav) on the mortality, locomotion, and feeding behavior of an important plant-feeding insect pest in rice, the brown planthopper, Nilaparvata lugens. Injecting dsRNA of Nan and Iav into fourth-instar nymphs significantly knocked down the target genes. The injection of dsNan or dsIav did not affect any morphological phenotype (including leg extension) of N. lugens nymphs and adults. Knockdown of Nan or Iav resulted in significantly decreased climbing activity against top plants but did not influence the leg-griping strength of adults. Knockdown of Nan resulted in a significantly elevated mortality of N. lugens in the observation period of 7 d after injection, whereas no significant difference in survival rates 7 d after injection was found between dsIav-injected and dsGFP-injected insects. Electropenetrographic (EPG) recordings indicated that knockdown of Nan and Iav reduced the ingestion activity in the rice phloem tissues of N. lugens. Knockdown of Nan and Iav significantly reduced the amount of honeydew excreted by N. lugens. Our findings indicated a relationship between TRPV and N. lugens locomotion and feeding behavior, which may help to fully elucidate the functions of TRPV in insects.


Sujet(s)
Hemiptera/génétique , Canaux cationiques TRPV/génétique , Animaux , Comportement alimentaire , Hemiptera/physiologie , Locomotion/génétique , Nymphe/génétique , Nymphe/physiologie , Oryza , Phloème , Interférence par ARN , Canaux cationiques TRPV/métabolisme
9.
Onco Targets Ther ; 11: 8643-8653, 2018.
Article de Anglais | MEDLINE | ID: mdl-30584323

RÉSUMÉ

BACKGROUND: Abnormal expression of miRNAs has been reported in osteosarcoma (OS), and miR-222-3p levels have been found to be increased in the serum of OS patients. However, the exact role of miR-222-3p in OS remains unclear. In the present study, we aimed to identify the molecular mechanism underlying the role of miR-222-3p in the development of OS. METHODS: We examined the expression level of miR-222-3p in OS tissues and OS cells using reverse-transcription quantitative PCR (RT-qPCR) analysis. MTT, colony formation, and transwell invasion assays were used to analyze the effects of miR-222-3p on the proliferation and invasion ability of OS cells. Luciferase reporter gene assays were used to confirm the target gene of miR-222-3p in OS cells. Tumor xenografts were then used to investigate the role of miR-222-3p in OS growth in vivo. RESULTS: The data of the present study demonstrated that miR-222-3p levels were increased in OS tissues and OS cells. Downregulation of miR-222-3p significantly inhibited the proliferation, migration, and invasion of OS cells in vitro. Further analysis revealed that tissue inhibitors of metalloproteinases 3 (TIMP3) is one of the functional target genes of miR-222-3p, and inhibition of TIMP3 efficiently rescues the blocking of cell proliferation and invasion mediated by miR-222-3p inhibitor in OS cells. CONCLUSION: Our findings constitute evidence that miR-222-3p promotes OS cell proliferation and invasion through targeting TIMP3 mRNA and provide novel insight into the mechanism underlying the development of OS.

10.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 4): m396-7, 2012 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-22589782

RÉSUMÉ

In the title compound, [Cd(C(2)H(8)N(2))(3)](GeF(6)), the Cd(II) atom, lying on a 32 symmetry site, is coordinated by six N atoms from three ethyl-enediamine (en) ligands in a distorted octa-hedral geometry. The Ge atom also lies on a 32 symmetry site and is coordinated by six F atoms. The en ligand has a twofold rotation axis passing through the mid-point of the C-C bond. The F atom is disordered over two sites with equal occupancy factors. In the crystal, the [Cd(en)(3)](2+) cations and [GeF(6)](2-) anions are connected through N-H⋯F hydrogen bonds, forming a three-dimensional supra-molecular network.

11.
Food Microbiol ; 30(1): 311-5, 2012 May.
Article de Anglais | MEDLINE | ID: mdl-22265317

RÉSUMÉ

It is well recognized that Salmonella can survive long-term starvation and desiccation stresses and contaminate foods that have intermediate to low water activities; however, little is known about the specific molecular mechanisms underlying its survival and persistence in low water activity foods. In this study, we used the RNA-seq approach to compare the transcriptomes (27-33 million 36-bp reads per sample) of a Salmonella enterica subsp. enteric serovar Enteritidis strain ATCC BAA-1045 after inoculation in peanut oil (water activity 0.30) for 72 h, 216 h and 528 h to those grown in Luria-Bertani (LB) broth for 12 h and 312 h. Our results showed that desiccated Salmonella cells in peanut oil were in a physiologically dormant state with <5% of its genome being transcribed compared to 78% in LB broth. Among the few detected transcripts in peanut oil, genes involved in heat and cold shock response, DNA protection and regulatory functions likely play roles in cross protecting Salmonella from desiccation and starvation stresses. In addition, non-coding RNAs may also play roles in Salmonella desiccation stress response. This is the first report of using RNA-seq technology in characterizing bacterial transcriptomes in a food matrix.


Sujet(s)
Dessiccation , Huiles végétales/métabolisme , Salmonella enteritidis/génétique , Transcriptome , Contamination des aliments/analyse , Microbiologie alimentaire/méthodes , Huile d'arachide , ARN bactérien/génétique , ARN bactérien/isolement et purification , Salmonella enteritidis/croissance et développement , Analyse de séquence d'ARN , Stress physiologique
12.
Dalton Trans ; 41(3): 734-6, 2012 Jan 21.
Article de Anglais | MEDLINE | ID: mdl-22127541

RÉSUMÉ

A novel aluminoborate (NH(4))(6)[C(5)NH(12)](6)[Al(12)B(65)O(105)(OH)(33)]·(H(2)O)(15) (QD-6), has been synthesized under mild hydrothermal conditions and characterized by IR, elemental analysis, TGA, powder and single-crystal X-ray diffractions. This compound crystallizes in the rhombohedral space group R3 (No. 148) with the lattice constants a = 23.7421(2) Å, c = 24.7699(3) Å, V = 12091.9(2) Å(3), and Z = 3. QD-6 consists of two unprecedented aluminoborate clusters, [Al(6)B(34)O(54)(OH)(18)](6-) and [Al(6)B(31)O(51)(OH)(15)](6-), which are built from the same hexagon-like [B@Al(6)O(24)] clusters and [B(11)O(17)(OH)(6)] or [B(10)O(16)(OH)(5)] polyborates.

13.
Appl Environ Microbiol ; 77(17): 5966-72, 2011 Sep.
Article de Anglais | MEDLINE | ID: mdl-21764970

RÉSUMÉ

Listeria monocytogenes can change its cellular morphology from bacilli to cocci during the transition to the long-term-survival (LTS) phase. The LTS cells demonstrated increased baro- and thermotolerance compared to their vegetative counterparts. So far, the underlying mechanisms that trigger this morphological and physiological transition remain largely unknown. In this study, we compared the transcriptomic profiles of L. monocytogenes serotype 4b strain F2365 at different growth stages in tryptic soy broth with yeast extract (TSBYE) using a whole-genome DNA chip approach. We identified a total of 225 differentially expressed genes (≥4-fold; P < 0.05) during the transition to the LTS phase in TSBYE. Genes related to cell envelope structure, energy metabolism, and transport were most significantly upregulated in the LTS phase. The upregulation of compatible solute transporters may lead to the accumulation of cellular solutes, lowering intracellular water activity and thus increasing bacterial stress resistance during the transition to the LTS phase. The downregulation of genes associated with protein synthesis may indicate a status of metabolic dormancy of the LTS cells. The transcriptomic profiles of resuscitated LTS cells in fresh TSBYE resembled those of log-phase cells (r=0.94), as the LTS cells rapidly resume metabolic activities and transit back to log phase with decreased baro- and thermotolerance.


Sujet(s)
Régulation de l'expression des gènes bactériens , Listeria monocytogenes/physiologie , Stress physiologique , Transcriptome , Listeria monocytogenes/génétique , Analyse sur microréseau , Séquençage par oligonucléotides en batterie
14.
BMC Genomics ; 11: 500, 2010 Sep 16.
Article de Anglais | MEDLINE | ID: mdl-20846431

RÉSUMÉ

BACKGROUND: Bacterial pathogens often show significant intraspecific variations in ecological fitness, host preference and pathogenic potential to cause infectious disease. The species of Listeria monocytogenes, a facultative intracellular pathogen and the causative agent of human listeriosis, consists of at least three distinct genetic lineages. Two of these lineages predominantly cause human sporadic and epidemic infections, whereas the third lineage has never been implicated in human disease outbreaks despite its overall conservation of many known virulence factors. RESULTS: Here we compare the genomes of 26 L. monocytogenes strains representing the three lineages based on both in silico comparative genomic analysis and high-density, pan-genomic DNA array hybridizations. We uncover 86 genes and 8 small regulatory RNAs that likely make L. monocytogenes lineages differ in carbohydrate utilization and stress resistance during their residence in natural habitats and passage through the host gastrointestinal tract. We also identify 2,330 to 2,456 core genes that define this species along with an open pan-genome pool that contains more than 4,052 genes. Phylogenomic reconstructions based on 3,560 homologous groups allowed robust estimation of phylogenetic relatedness among L. monocytogenes strains. CONCLUSIONS: Our pan-genome approach enables accurate co-analysis of DNA sequence and hybridization array data for both core gene estimation and phylogenomics. Application of our method to the pan-genome of L. monocytogenes sheds new insights into the intraspecific niche expansion and evolution of this important foodborne pathogen.


Sujet(s)
Variation génétique , Génome bactérien/génétique , Listeria monocytogenes/génétique , Cartographie chromosomique , Hybridation génomique comparative , Séquence conservée/génétique , Gènes bactériens/génétique , Locus génétiques/génétique , Humains , Voies et réseaux métaboliques/génétique , Phylogenèse , ARN bactérien/génétique , Courbe ROC , Normes de référence , Analyse de séquence d'ADN , Similitude de séquences d'acides nucléiques , Spécificité d'espèce
15.
Appl Environ Microbiol ; 76(15): 5013-24, 2010 Aug.
Article de Anglais | MEDLINE | ID: mdl-20562293

RÉSUMÉ

Salmonella enterica serovars Enteritidis and Typhimurium are the leading causative agents of salmonellosis in the United States. S. Enteritidis is predominantly associated with contamination of shell eggs and egg products, whereas S. Typhimurium is frequently linked to tainted poultry meats, fresh produce, and recently, peanut-based products. Chlorine is an oxidative disinfectant commonly used in the food industry to sanitize the surfaces of foods and food processing facilities (e.g., shell eggs and poultry meats). However, chlorine disinfection is not always effective, as some S. enterica strains may resist and survive the disinfection process. To date, little is known about the underlying mechanisms of how S. enterica responds to chlorine-based oxidative stress. In this study, we designed a custom bigenome microarray that consists of 385,000 60-mer oligonucleotide probes and targets 4,793 unique gene features in the genomes of S. Enteritidis strain PT4 and S. Typhimurium strain LT2. We explored the transcriptomic responses of both strains to two different chlorine treatments (130 ppm of chlorine for 30 min and 390 ppm of chlorine for 10 min) in brain heart infusion broth. We identified 209 S. enterica core genes associated with Fe-S cluster assembly, cysteine biosynthesis, stress response, ribosome formation, biofilm formation, and energy metabolism that were differentially expressed (>1.5-fold; P < 0.05). In addition, we found that serovars Enteriditis and Typhimurium differed in the responses of 33 stress-related genes and 19 virulence-associated genes to the chlorine stress. Findings from this study suggest that the oxidative-stress response may render S. enterica resistant or susceptible to certain types of environmental stresses, which in turn promotes the development of more effective hurdle interventions to reduce the risk of S. enterica contamination in the food supply.


Sujet(s)
Chlore/pharmacologie , Désinfectants/pharmacologie , Analyse de profil d'expression de gènes , Stress oxydatif , Salmonella enteritidis/effets des médicaments et des substances chimiques , Salmonella typhimurium/effets des médicaments et des substances chimiques , Séquençage par oligonucléotides en batterie
16.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 4): o798-9, 2010 Mar 13.
Article de Anglais | MEDLINE | ID: mdl-21580636

RÉSUMÉ

The title compound, 2C(2)H(10)N(2) (2+)·B(14)O(20)(OH)(6) (4-), consists of a centrosymmetric tetra-deca-borate anion and two ethyl-enediammonium cations. The anions are inter-connected through strong O-H⋯O hydrogen bonds into a three-dimensional supra-molecular network with channels along [100], [010], [001] and [111]. The diprotonated cations reside in the channels and inter-act with the inorganic framework by extensive N-H⋯O hydrogen bonds.

17.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 5): m550-1, 2009 Apr 22.
Article de Anglais | MEDLINE | ID: mdl-21583784

RÉSUMÉ

A new lanthanum(III)-copper(I) heterometallic coordination polymer, [Cu(7)La(3)Br(6)(C(6)H(4)NO(2))(8)(C(8)H(4)O(4))(H(2)O)(4)](n), has been prepared by a hydro-thermal method. Of the three La atoms in the asymmetric unit, two are eight-coordinate with bicapped trigonal-prismatic configurations; the third is nine-coordinated and has a tricapped trigonal-prismatic coordination geometry. Of the seven Cu atoms, two are two-coordinate with CuBrN and CuN(2) ligand sets, three have trigonal configurations, viz. CuBrN(2), CuBr(2)N and CuBr(3), while the remaining two adopt distorted tetra-hedral CuBr(3)N geometries. In the crystal structure, adjacent La centers are linked by isonicotinate (IN(-)) and benzene-1,2-dicarboxyl-ate ligands to form a two-dimensional La-carboxyl-ate layer in the ab plane. These layers are further inter-connected with each other by bridging [Cu(IN)(2)] motifs, leading to an unusual three-dimensional heterometallic Cu-halide-lanthanide-organic framework, with the inorganic [Cu(6)Br(6)](n) chains located in the resulting channels. Two Cu atoms are disordered over two positions, both with site occupancy factors of 0.80 and 0.20. O-H⋯O hydrogen bonding between water molecules and carboxylate O atoms helps to consolidate the crystal packing.

18.
Inorg Chem ; 47(4): 1270-2, 2008 Feb 18.
Article de Anglais | MEDLINE | ID: mdl-18211001

RÉSUMÉ

QD-3, a novel aluminoborate (TETA) 2[Al 2B 10 O 20].0.25H 2O (TETA = triethylenetetramine), has been solvothermally synthesized and characterized by IR, thermogravimetric analysis, power X-ray diffraction, elemental analysis, and single-crystal X-ray diffraction. This compound crystallizes in the orthorhombic system, space group Pna2 1 (No. 33), a = 25.9174(2) A, b = 7.4028(5) A, c = 17.013(4) A, V = 3264.2(2) A (3), and Z = 4. Its structure consists of AlO 4 tetrahedra and B 5O 10 clusters, which are interconnected and form a three-dimensional framework with large 11-, 12-, and 14-ring channels.

19.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): m1260-1, 2008 Sep 13.
Article de Anglais | MEDLINE | ID: mdl-21201015

RÉSUMÉ

A new thulium(III)-copper(I) heterometallic coordination polymer, [Cu(4)Tm(2)Br(3)(C(6)H(4)NO(2))(6)(OH)(H(2)O)(4)](n), has been prepared by a hydro-thermal method. The Tm and both Cu atoms lie on mirror planes. The Tm atom is seven-coordinate with a capped distorted trigonal-prismatic coordination geometry, while the Cu atoms adopt trigonal CuBrN(2) and tetra-hedral CuBr(3)N coordination modes, respectively. The Cu atom in the trigonal coordination environment is disordered over two sites of equal occupancy. The crystal structure is constructed from two distinct units of dimeric [Tm(2)(µ(2)-OH(IN)(6)(H(2)O)(4)] cores (IN = isonicotinate) and one-dimensional inorganic [Cu(4)Br(3)](n) chains, which are linked together, forming heterometallic Cu-halide-lanthanide-organic layers.

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