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1.
World J Gastroenterol ; 27(42): 7311-7323, 2021 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-34876791

RESUMO

BACKGROUND: An increased amount of Fusobacterium nucleatum (F. nucleatum) is frequently detected in the gastric cancer-associated microbiota of the Taiwanese population. F. nucleatum is known to exert cytotoxic effects and play a role in the progression of colorectal cancer, though the impact of F. nucleatum colonization on gastric cancer cells and patient prognosis has not yet been examined. AIM: To identify F. nucleatum-dependent molecular pathways in gastric cancer cells and to determine the impact of F. nucleatum on survival in gastric cancer. METHODS: Coculture of F. nucleatum with a gastric cancer cell line was performed, and changes in gene expression were investigated. Genes with significant changes in expression were identified by RNA sequencing. Pathway analysis was carried out to determine deregulated cellular functions. A cohort of gastric cancer patients undergoing gastrectomy was recruited, and nested polymerase chain reaction was performed to detect the presence of F. nucleatum in resected cancer tissues. Statistical analysis was performed to determine whether F. nucleatum colonization affects patient survival. RESULTS: RNA sequencing and subsequent pathway analysis revealed a drastic interferon response induced by a high colonization load. This response peaked within 24 h and subsided after 72 h of incubation. In contrast, deregulation of actin and its regulators was observed during prolonged incubation under a low colonization load, likely altering the mobility of gastric cancer cells. According to the clinical specimen analysis, approximately one-third of the gastric cancer patients were positive for F. nucleatum, and statistical analysis indicated that the risk for colonization increases in late-stage cancer patients. Survival analysis demonstrated that F. nucleatum colonization was associated with poorer outcomes among patients also positive for Helicobacter pylori (H. pylori). CONCLUSION: F. nucleatum colonization leads to deregulation of actin dynamics and likely changes cancer cell mobility. Cohort analysis demonstrated that F. nucleatum colonization leads to poorer prognosis in H. pylori-positive patients with late-stage gastric cancer. Hence, combined colonization of F. nucleatum and H. pylori is a predictive biomarker for poorer survival in late-stage gastric cancer patients treated with gastrectomy.


Assuntos
Neoplasias Colorretais , Infecções por Fusobacterium , Helicobacter pylori , Neoplasias Gástricas , Fusobacterium nucleatum , Humanos
2.
Chin J Nat Med ; 16(8): 572-579, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30197122

RESUMO

Farnesoid X receptor (FXR) is a member of the nuclear receptor superfamily of ligand-activated transcription factors. As a metabolic regulator, FXR plays key roles in bile acid and cholesterol metabolism and lipid and glucose homeostasis. Therefore, FXR is a potential drug target for several metabolic syndromes, especially those related to lipidemia disorders. In the present study, we identified small molecule SIPI-7623, a derivative of an extract from Oriental wormwood (Artemisia capillaris), and found that it specifically upregulated the expression of cholesterol-7-alpha-hydroxylase (CYP7A1), downregulated the expression of sterol-regulatory element-binding protein 1c (SREBP-1c) in the liver, and inhibited the expression of ileal bile acid binding-protein (IBABP) in the ileum of rats. We found that inhibition of FXR by SIPI-7623 decreased the level of cholesterol and triglyceride. SIPI-7623 reduced the levels of cholesterol and triglyceride in in vitro HepG2 cell models, ameliorated diet-induced atherosclerosis, and decreased the serum lipid content on rats and rabbits model of atherosclerosis in vivo. Furthermore, SIPI-7623 decreased the extent of atherosclerotic lesions. Our resutls demonstrated that antagonism of the FXR pathway can be employed as a therapeutic strategy to treat metabolic diseases such as hyperlipidemia and atherosclerosis. In conclusion, SIPI-7623 could be a promising lead compound for development of drugs to treat hyperlipidemia and atherosclerosis.


Assuntos
Artemisia/química , Aterosclerose/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/administração & dosagem , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Animais , Aterosclerose/genética , Aterosclerose/metabolismo , Colesterol/metabolismo , Colesterol 7-alfa-Hidroxilase/genética , Colesterol 7-alfa-Hidroxilase/metabolismo , Humanos , Hiperlipidemias/genética , Hiperlipidemias/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Coelhos , Ratos , Ratos Sprague-Dawley , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Triglicerídeos/metabolismo
3.
BMC Cancer ; 18(1): 508, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29720137

RESUMO

BACKGROUND: Gastric cancer is the eighth most common cancer in Taiwan, with a 40% 5-year survival rate. Approximately 40% of patients are refractory to chemotherapy. Currently, the anti-HER2 therapy is the only clinically employed targeted therapy. However, only 7% patients in Taiwan are HER2-positive. Identifying candidate target genes will facilitate the development of adjuvant targeted therapy to increase the efficacy of gastric cancer treatment. METHODS: Clinical specimens were analyzed by targeted RNA sequencing to assess the expression levels of target genes. Statistical significance of differential expression and correlation between specimens was evaluated. The correlation with patient survival was analyzed as well. In vitro cell mobility was determined using wound-healing and transwell mobility assays. RESULTS: Expression of BMP1, COL1A1, STAT3, SOX2, FOXA2, and GATA6 was progressively dysregulated through the stages of gastric oncogenesis. The expression profile of these six genes forms an ubiquitously biomarker signature that is sufficient to differentiate cancer from non-cancerous specimens. High expression status of BMP1 correlates with poor long-term survival of late-stage patients. In vitro, suppression of BMP1 inhibits the mobility of the gastric cancer cell lines, indicating a role of BMP1 in metastasis. CONCLUSIONS: BMP1 is upregulated in gastric cancer and is correlated with poor patient survival. Suppression of BMP1 reduced gastric cancer mobility in vitro. Our finding suggests that anti-BMP1 therapy will likely augment the efficacy of standard chemotherapy and improve the treatment outcome.


Assuntos
Biomarcadores Tumorais/análise , Proteína Morfogenética Óssea 1/biossíntese , Neoplasias Gástricas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/mortalidade , Regulação para Cima
4.
Sci Rep ; 8(1): 158, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29317709

RESUMO

Helicobacter pylori is recognised as a main risk factor for gastric cancer. However, approximately half of the patients with gastritis are negative for H. pylori infection, and the abundance of H. pylori decreases in patients with cancer. In the current study, we profiled gastric epithelium-associated bacterial species in patients with gastritis, intestinal metaplasia, and gastric cancer to identify additional potential pathogenic bacteria. The overall composition of the microbiota was similar between the patients with gastritis and those with intestinal metaplasia. H. pylori was present in half of the non-cancer group, and the dominant bacterial species in the H. pylori-negative patients were Burkholderia, Enterobacter, and Leclercia. The abundance of those bacteria was similar between the cancer and non-cancer groups, whereas the frequency and abundance of H. pylori were significantly lower in the cancer group. Instead, Clostridium, Fusobacterium, and Lactobacillus species were frequently abundant in patients with gastric cancer, demonstrating a gastric cancer-specific bacterial signature. A receiver operating characteristic curve analysis showed that Clostridium colicanis and Fusobacterium nucleatum exhibited a diagnostic ability for gastric cancer. Our findings indicate that the gastric microenvironment is frequently colonised by Clostridium and Fusobacterium in patients with gastric cancer.


Assuntos
Infecções por Clostridium/complicações , Clostridium , Infecções por Fusobacterium/complicações , Fusobacterium , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/etiologia , Adulto , Idoso , Infecções por Clostridium/microbiologia , Feminino , Infecções por Fusobacterium/microbiologia , Humanos , Masculino , Metaplasia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , RNA Ribossômico 16S/genética , Neoplasias Gástricas/diagnóstico , Taiwan , Adulto Jovem
5.
Int J Mol Sci ; 17(9)2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27598141

RESUMO

Aberrant Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling is crucial to the development of gastric cancer. In this study, we examined the role of STAT3 in the expression and methylation of its targets in gastric cancer patients. Results from RNA sequencing identified an inverse correlation between the expression of STAT3 and GATA6 in 23 pairs of gastric cancer patient samples. We discovered that the expression of GATA6 is epigenetically silenced through promoter methylation in gastric cancer cell lines. Interestingly, the inhibition of STAT3 using a novel STAT3 inhibitor restored the expression of GATA6 and its targets, trefoil factors 1 and 2 (TFF1/2). Moreover, disruption of STAT3 binding to GATA6 promoter by small hairpin RNA restored GATA6 expression in AGS cells. A clinically significant correlation was also observed between the expression of GATA6 and TFF1/2 among tissue samples from 60 gastric cancer patients. Finally, bisulfite pyrosequencing revealed GATA6 methylation in 65% (39/60) of the patients, and those with higher GATA6 methylation tended to have shorter overall survival. In conclusion, we demonstrated that aberrant JAK/STAT signaling suppresses TFF1/2 partially through the epigenetic silencing of GATA6. Therapeutic intervention of STAT3 in reversing the epigenetic status of GATA6 could benefit the treatment of gastric cancer and is worthy of further investigation.


Assuntos
Fator de Transcrição GATA6/metabolismo , Inativação Gênica , Transdução de Sinais , Neoplasias Gástricas/metabolismo , Fator Trefoil-1/metabolismo , Fator Trefoil-2/metabolismo , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Feminino , Fator de Transcrição GATA6/genética , Humanos , Janus Quinases/genética , Janus Quinases/metabolismo , Masculino , Pessoa de Meia-Idade , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Neoplasias Gástricas/genética , Fator Trefoil-1/genética , Fator Trefoil-2/genética
6.
Biochem Biophys Rep ; 7: 230-239, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28955911

RESUMO

Sex-determining region Y (SRY)-box protein 2 (SOX2) plays a critical role in stem cell maintenance and carcinogenesis. In addition to its function as a minor-groove DNA binding transcription factor, our previous study showed that SOX2 also acts as a RNA binding protein. In current study, we first showed that SOX2 displayed high affinity toward the mRNA encoding S100A14 in BFTC905 and that depletion of SOX2 resulted in a decrease of S100A14 mRNA and protein level. To characterize the RNA binding sequence recognized by SOX2, oligomer-directed RNase H digestion was coupled to the cross-linking before immunoprecipitation assay to demonstrate that SOX2 preferentially binds to the 3'-UTR of the S100A14 mRNA. Using EGFP-S100A14 3'-UTR reporters and mobility shift assay, we identified that the binding sequence on the 3'-UTR of the S100A14 mRNA exhibits a stem-loop structure. Together, our data indicates that SOX2 enhances S100A14 expression by binding to the 3'-UTR of the S100A14 mRNA. Functionally, depletion of SOX2 increases growth and mobility of BFTC905. Knock-down of S100A14 in BFTC905 also leads to an increase in the number of the cells in the S phase and higher mobility, suggesting that SOX2 suppresses cell growth and mobility through promoting the expression of S100A14. Together, our experimental evidence indicates that SOX2 is capable of exerting its cellular functions by functioning as an RNA binding protein in post-transcriptional regulation.

7.
Chin J Nat Med ; 12(10): 768-76, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25443370

RESUMO

AIM: JS-38 (mitothiolore), a synthetic version of a metabolite isolated from Xenorhabdus sp., was evaluated for its anti-tumor and white blood cell (WBC) elevating activities. METHOD: These anti-proliferative activities were assessed in vitro using a panel of ten cell lines. The anti-tumor activities were tested in vivo using B16 allograft mouse models and xenograft models of A549 human lung carcinoma and QGY human hepatoma in nude mice. The anti-tumor interactions of JS-38 and cyclophosphamide (CTX) or 5-fluorouracil (5-Fu) were studied in a S180 sarcoma model in ICR mice. Specific stimulatory effects were determined on peripheral neutrophils in normal and CTX- and 5-Fu-induced neutropenic mice. RESULTS: The IC50 values ranged from 0.1 to 2.0 µmol·L(-1). JS-38 (1 µmol·L(-1)) caused an increase in A549 tumor cell apoptosis. Multi-daily gavage of JS-38 (15, 30, and 60 mg·kg(-1)·d(-1)) inhibited in vivo tumor progression without a significant effect on body weight. JS-38 additively enhanced the in vivo anti-tumor effects of CTX or 5-Fu. JS-38 increased peripheral neutrophil counts and neutrophil rates in normal BALB/c mice almost as effectively as granulocyte colony-stimulating factor (G-CSF). In mice with neutropenia induced by CTX or 5-Fu, JS-38 rapidly restored neutrophil counts. CONCLUSION: These results suggest that JS-38 has anti-tumor activity, and also has the ability to increase peripheral blood neutrophils.


Assuntos
Antineoplásicos/administração & dosagem , Hidrocarbonetos Fluorados/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Neutrófilos/efeitos dos fármacos , Xenorhabdus/química , Animais , Antineoplásicos/metabolismo , Contagem de Células , Feminino , Humanos , Hidrocarbonetos Fluorados/metabolismo , Neoplasias Pulmonares/fisiopatologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Neutrófilos/citologia , Xenorhabdus/metabolismo
8.
FEBS J ; 281(23): 5194-207, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25238490

RESUMO

Alternative splicing of pre-mRNA, catalyzed by small nuclear ribonucleoproteins (snRNPs), plays an important role in proteome complexity and the modulation of cellular functions. snRNP polypeptide N (SmN), is tissue-specifically expressed, where it replaces snRNP polypeptide B (SmB)/B' in the Sm core assembly of snRNPs. Recent studies have demonstrated that perturbation of snRNPs leads to alternative splicing, but whether SmN modulates functions of the splicing machinery remains unclear. In this study, we found that ectopic expression of SmN increased utilization of the proximal 5' splice site on an adenovirus early gene 1A reporter. To evaluate the molecular mechanisms underlying SmN-dependent alternative splicing, we generated a HeLa cell line with an inducible expression system for SmN. Upon SmN induction, SmB/B' expression decreased dramatically, despite only small changes in the level and splicing pattern of SNRPB mRNA. In addition, SmN was incorporated into the U2 snRNP but not into the U1 snRNP after induction. Sedimentation analysis revealed a decrease in the level of mature U2 snRNP. This result suggests that SmN incorporation into the Sm core may impede processing, decreasing the level of functional U2 snRNP. We also found that the inclusion frequencies of alternatively spliced exons in the bridging integrator 1 and exocyst complex component 7 (EXOC7) genes were modulated by SmN expression. An enhanced GFP-EXOC7 reporter was used to confirm that SmN increases the inclusion frequency of EXOC7 exon 7. Taken together, our findings indicate that SmN expression reduces the level of mature U2 snRNP, leading to alternative splicing.


Assuntos
Processamento Alternativo , Proteínas Centrais de snRNP/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Células Cultivadas , Doxiciclina/farmacologia , Imunofluorescência , Células HeLa , Humanos , Proteínas Nucleares/genética , Ribonucleoproteína Nuclear Pequena U2/análise , Ribonucleoproteína Nuclear Pequena U2/fisiologia , Proteínas Supressoras de Tumor/genética , Proteínas de Transporte Vesicular/genética
9.
Acta Crystallogr C ; 69(Pt 10): 1124-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24096499

RESUMO

In the title compound, [Ni(C14H8N2O5)(H2O)2]n, the Ni(II) cation is six-coordinate with a slightly distorted octahedral coordination geometry and the 4-(isonicotinamido)phthalate ligand links the Ni(II) centres into a three-dimensional structure with sra topology. The structure is also stabilized by N-H···O hydrogen bonding between the uncoordinated amide groups of the ligand and extensive O-H···O hydrogen bonding between the two coordinated water molecules. The magnetic and thermal stability properties of the title compound are also discussed.

10.
Artigo em Inglês | MEDLINE | ID: mdl-24046547

RESUMO

In the title compound, {[NiTb2(C14H8N2O5)4(H2O)4]·4H2O} n , the Tb(III) ion is coordinated by one water mol-ecule and seven O atoms from four 5-(pyridine-4-carboxamido)-isophthalate (L) ligands in a distorted square-anti-prismatic arrangement, while the Ni(II) ion, lying on an inversion center, is six-coordinated in an octa-hedral geometry by two pyridine N atoms, two carboxyl-ate O atoms and two water mol-ecules. One L ligand bridges two Tb(III) ions and one Ni(II) ion through two carboxyl-ate groups and one pyridine N atom. The other L ligand bridges two Tb(III) ions and one Ni(II) ion through two carboxyl-ate groups, while the uncoordinating pyridine N atom is hydrogen bonded to an adjacent coordinating water mol-ecule. Extensive O-H⋯O, N-H⋯O and O-H⋯N hydrogen bonds play an important role in stabilizing the crystal structure.

11.
Acta Crystallogr C ; 68(Pt 8): m219-22, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22850846

RESUMO

In the title compound, {[Co(C(14)H(8)N(2)O(5))(C(10)H(8)N(2))]·3H(2)O}(n), the Co(II) cation is five-coordinated with a slightly distorted trigonal-bipyramidal geometry, and the 5-isonicotinamidoisophthalate ligands link Co(II) atoms into a layered structure. These two-dimensional arrays are further pillared by rod-like 4,4'-bipyridine ligands to give a three-dimensional framework with pcu (primitive cubic) topology. The magnetic and adsorption properties of the title compound are also discussed.

12.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 4): m517, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22589867

RESUMO

In the title compound, [Zn(C(8)H(6)ClNO(4)S)(C(10)H(8)N(2))(H(2)O)], the Zn(II) atom is six-coordinated by two O atoms and one N atom from a tridentate Schiff base ligand and two N atoms from a chelating 2,2'-bipyridine ligand and one water mol-ecule, forming a slightly distorted octa-hedral geometry. In the crystal, O-H⋯O hydrogen bonds link pairs of complex mol-ecules into dimers. An intra-molecular O-H⋯O hydrogen bond is also present.

13.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 5): m530, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22590058

RESUMO

In the title compound, {[Ce(C(14)H(9)N(2)O(5))(C(14)H(8)N(2)O(5))(H(2)O)(2)]·H(2)O}(n), three carboxyl groups of two independent isophthalate anions are deprotonated and they bridge the Ce(III) cations, forming a two-dimensional polymeric structure parallel to (001); another carboxyl group is not deprotonated and links with the adjacent pyridine ring via an O-H⋯N hydrogen bond. The Ce(III) cation is coordinated by six O atoms from carboxyl groups and two O atoms from coordinated water mol-ecules in a distorted square-anti-prismatic arrangement. Extensive O-H⋯O and O-H⋯N hydrogen bonding occurs in the crystal structure.

14.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 9): m1298, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22058886

RESUMO

In the title compound, {[Nd(C(14)H(9)N(2)O(5))(C(14)H(8)N(2)O(5))]·2H(2)O}(n), the Nd(III) atom is eight-coordinated as it is surrounded by eight carboxyl-ate O atoms from six ligands in a distorted square-anti-prismatic arrangement. The Nd(III) atoms are linked by HL(-) and L(2-) ligands [H(2)L is 5-(pyridine-4-carboxamido)-isophthalic acid], forming a bilayer network. The layers are linked into a three-demensional network through N-H⋯O and O-H⋯O hydrogen bonds.

15.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): m1431-2, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22064912

RESUMO

In the centrosymmetric polymeric title compound, {[CoGd(2)(C(14)H(8)N(2)O(5))(4)(H(2)O)(4)]·4H(2)O}(n), the Gd(III) cation is coordinated by one water mol-ecule and four pyridine-4-carboxamido-isophthalate (L) anions in a distorted square-anti-prismatic arrangement, while the Co(II) cation, located on an inversion center, is coordinated by two pyridyl-N atoms, two carboxyl-ate-O atoms and two water mol-ecules in a distorted octa-hedral geometry. The asymmetric unit contains two anionic L ligands: one bridges two Gd cations and one Co cation through two carboxyl groups and one pyridine-N atom; the other bridges two Gd cations and one Co cation through two carboxyl groups and the uncoordinated pyridine-N atom is hydrogen-bonded to the adjacent coordinated water mol-ecule. Extensive O-H⋯O and N-H⋯O hydrogen bonds are present in the crystal structure.

16.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 11): m1478-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22219735

RESUMO

In the centrosymmetric polymeric title compound, {[CoEr(2)(C(14)H(8)N(2)O(5))(4)(H(2)O)(4)]·4H(2)O}(n), the Er(III) cation has a coordination number of eight and is surrounded by seven carboxyl-ate O atoms from four 5-(pyridine-4-carboxamido)-isophthalate (L) ligands and one water mol-ecule, forming a distorted square-anti-prismatic arrangement. The Co(II) cation is located on an inversion center and is coordinated by two pyridine N atoms, two carboxyl-ate O atoms and two water mol-ecules in a distorted octa-hedral geometry. The asymmetric unit contains two anionic L ligands. One bridges two Er(III) cations and one Co(II) cation through two carboxyl-ate groups and one pyridine N atom, while the other bridges two Er(III) cations and one Co(II) cation through two carboxyl-ate groups. Extensive O-H⋯O, O-H⋯N and N-H⋯O hydrogen-bonding inter-actions are present in the crystal, involving all uncoordinated water mol-ecules and the uncoordinated pyridine N atom of one of the ligands bonded to an adjacent coordinated water mol-ecule. The title compound is isotypic with the gadolinium analogue.

17.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 11): m1574-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22219811

RESUMO

In the centrosymmetric polymeric title compound, {[CoHo(2)(C(14)H(8)N(2)O(5))(4)(H(2)O)(4)]·4H(2)O}(n), the Ho(III) ion is coordinated by one water mol-ecule and four 5-(pyridine-4-carboxamido)-isophthalate (L) ligands in a distorted square-anti-prismatic arrangement. The Co(II) ion, located on an inversion center, is coordinated by two pyridine N atoms, two carboxyl-ate O atoms and two water mol-ecules in a distorted octa-hedral geometry. One L ligand bridges two Ho ions and one Co ion through two carboxyl-ate groups and one pyridine N atom. The other L ligand bridges two Ho ions and one Co ion through two carboxyl-ate groups, while the uncoordinated pyridine N atom accepts a hydrogen bond from an adjacent coordinated water mol-ecule. Extensive O-H⋯O, N-H⋯O and O-H⋯N hydrogen bonding is present in the crystal.

18.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 10): m1253-4, 2010 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-21587402

RESUMO

The title compound, {[Cd(C(19)H(13)N(4)O(4))(2)(H(2)O)(2)]·4H(2)O}(n) or {[Cd(BBA)(2)(H(2)O)(2)]·4H(2)O}(n), where BBA is 3,5-bis-(iso-nicotin-amido)-benzoate, is isotypic with its Mn isologue [Chen et al. (2009 ▶). J. Coord. Chem.62, 2421-2428]. The cation sits on a twofold axis and is six-coordinated in a slightly distorted octa-hedral geometry; the polyhedra are linked into zigzag chains, which are further connected by N-H⋯O, O-H⋯O and O-H⋯N hydrogen bonds as well as π-π inter-actions [centroid-centroid distance of 3.639 (2) Å], giving a three-dimensional supra-molecular framework.

19.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): m1482, 2009 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-21578204

RESUMO

In the title linear coordination polymer, {[Cu(C(2)H(3)O(2))(2)(C(12)H(10)N(4))]·2H(2)O}(n), the Cu(II) atom is coordinated by two N atoms from two different symmetry-related 1,4-diimidazol-1-ylbenzene (dib) ligands and two carboxyl-ate O atoms from two acetate ligands in a square-planar geometry. The Cu atoms are linked by the dib ligands, forming an extended chain. These chains are linked by O-H⋯O hydrogen bonds into a three-dimensional supra-molecular network. The Cu(II) atom lies on a center of inversion.

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