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2.
J Exp Bot ; 71(4): 1540-1550, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31677347

RESUMO

Neighbor detection and allelochemical response are important mediators in plant-plant interactions. Although there is increasing knowledge about plant allelochemicals released in response to the presence of competitors and involved in neighbor-derived signaling, less is known about which signaling chemicals are responsible for the neighbor-induced allelochemical response. Here, we experimentally demonstrate that (-)-loliolide, a carotenoid metabolite, acts as a signaling chemical in barnyardgrass-rice allelopathic interactions. The production of the rice allelochemicals momilactone B and tricin was increased in the presence of five biotypes of barnyardgrass. (-)-Loliolide was found in all the biotypes of barnyardgrass and their root exudates and rhizosphere soils. There were significant positive relationships between rice allelochemicals and (-)-loliolide concentrations across the biotypes of barnyardgrass. Furthermore, (-)-loliolide elicited the production of momilactone B and tricin. Comparative transcriptomic analysis revealed regulatory activity of (-)-loliolide on the diterpenoid and flavonoid biosynthesis pathway. The expression of key genes involved in the biosynthesis of momilactone B (CPS4, KSL4, and MAS) and tricin (CYP75B3 and CYP75B4) was up-regulated by (-)-loliolide. These findings suggest that (-)-loliolide acts as a signaling chemical and participates in barnyardgrass-rice allelopathic interactions. Allelopathic rice plants can detect competing barnyardgrass through the presence of this signaling chemical and respond by increasing levels of their allelochemicals to achieve an advantage for their own growth.

3.
Dalton Trans ; 49(3): 651-658, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31844872

RESUMO

A novel 3D coordination polymer {[Cu4.5 (BTZE)1.5 (µ3-OH)3(µ-OH)(SO4)(H2O)1.5·4H2O]}n (1) was synthesized by a solvothermal reaction of 1,2-bis(tetrazol-5-yl) ethane (BTZE) with copper sulfate. Compound (1) contained triangular [Cu3(µ3-OH)] cluster based magnetic Δ-chains linked with in situ generated µ2-BTZE ligands to form a 2D cyclic annular layer. This 2D layer structure was further modified with sulfate and symmetry-related µ3-OH groups, extending to a 3D coordination framework structure. The magnetic performance of (1) was characterized in the temperature range of 2-300 K in terms of direct-current and alternating-current magnetic susceptibilities, revealing that (1) was a canted ferromagnet with a critical temperature (Tc) of 9.5 K. Notably, (1) behaved as a hard magnet with a coercive field of 2.3 kOe at 2 K, showing significant unique characteristics compared to those of the reported spin canting systems based on pure Cu(ii) ions.

4.
Dalton Trans ; 48(6): 2213-2219, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30681688

RESUMO

Based on the HMPA ligand, a new air- and moisture-stable pentagonal-bipyramidal DyIII single-ion magnet [Dy(HMPA)2(H2O)5]2·Br6·2HMPA·2H2O (1) was prepared and characterized. Single-crystal X-ray tests showed the two crystallographically independent DyIII ions located in a pentagonal-bipyramidal coordination sphere with strong axial HMPA ligands and weak equatorial water molecules relating to strong unaxial anisotropy. Direct-current and alternating-current magnetic susceptibilities were measured and showed that 1 exhibited slow relaxation of magnetization up to 36 K (1000 Hz) with an energy barrier of 556 K and blocking temperature of 7 K (defined by the peak temperature of zero-field cooling data). The application of a dc field and magnetic dilution were also carried out to explore the existing quantum tunelling of the magnetization process.

5.
Oncol Lett ; 17(1): 323-331, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30655770

RESUMO

Liver cancer, which is the second leading cause of tumor-associated mortality, is of great concern worldwide due to its resistance to chemotherapeutic drugs. Transcatheter arterial chemoembolization (TACE) has previously been used as a treatment for unresectable liver tumors in China; however, the response to TACE treatment differs between patients. It has been reported that hepatitis B virus (HBV)-as sociated tumors are less sensitive to TACE treatment compared with non-HBV-associated liver cancer. Previous studies have demonstrated that exosomes serve a crucial role in hepatic carcinoma chemoresistance. We therefore hypothesized that HBV may modulate chemosensitivity via exosomes. The aim of the present study was to investigate how exosomes affect chemoresistance by assessing their role in chaperone-mediated autophagy (CMA)-dependent chemoresistance in HBV-associated liver cancer. Iconography data from HBV-positive and HBV-negative patients with hepatic carcinoma receiving TACE treatment were assessed, and it was revealed that the tumor volume was decreased in the patients with non-HBV-associated liver cancer compared with that in the patients with HBV-associated tumors following TACE therapy. Furthermore, it was revealed that exosomes from HBV-infected liver cancer cells were able to downregulate cell apoptosis when treated with oxaliplatin compared with exosomes from normal HepG2 cells. Furthermore, the results demonstrated that HBV-associated exosomes modulate cell death via activating the CMA pathway, and its key molecule, lysosome-associated membrane protein (Lamp2a), was also upregulated. Lamp2a-knockdown was also found to reverse anti-apoptotic effects in liver cancer. Taken together, the results of the present study suggest that chemoresistance in patients with HBV-associated hepatic tumors may be mediated by exosomes, and thus may provide a basis for the development of novel treatment strategies for chemoresistant liver cancer.

6.
Acta Pharmacol Sin ; 40(4): 530-538, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29925919

RESUMO

We have reported that hepatitis B X-interacting protein (HBXIP, also termed LAMTOR5) can act as an oncogenic transcriptional co-activator to modulate gene expression, promoting breast cancer development. Pyruvate kinase muscle isozyme M2 (PKM2), encoded by PKM gene, has emerged as a key oncoprotein in breast cancer. Yet, the regulatory mechanism of PKM2 is still unexplored. Here, we report that HBXIP can upregulate PKM2 to accelerate proliferation of estrogen receptor positive (ER+) breast cancer. Immunohistochemistry analysis using breast cancer tissue microarray uncovered a positive association between the expression of HBXIP and PKM2. We also discovered that PKM2 expression was positively related with HBXIP expression in clinical breast cancer patients by real-time PCR assay. Interestingly, in ER+ breast cancer cells, HBXIP was capable of upregulating PKM2 expression at mRNA and protein levels in a dose-dependent manner, as well as increasing the activity of PKM promoter. Mechanistically, HBXIP could stimulate PKM promoter through binding to the -779/-579 promoter region involving co-activation of E2F transcription factor 1 (E2F1). In function, cell viability, EdU, colony formation, and xenograft tumor growth assays showed that HBXIP contributed to accelerating cell proliferation through PKM2 in ER+ breast cancer. Collectively, we conclude that HBXIP induces PKM2 through transcription factor E2F1 to facilitate ER+ breast cancer cell proliferation. We provide new evidence for the mechanism of transcription regulation of PKM2 in promotion of breast cancer progression.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Transporte/metabolismo , Fator de Transcrição E2F1/metabolismo , Proteínas de Membrana/metabolismo , Receptores Estrogênicos/metabolismo , Hormônios Tireóideos/metabolismo , Animais , Proliferação de Células , Sobrevivência Celular , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
7.
Arch Insect Biochem Physiol ; 100(1): e21511, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30417456

RESUMO

The Silkworm Bombyx mori is an important insect in terms of economics and a model organism with a complete metamorphosis. The economic importance of silkworms is dependent on the functions of the silkgland, a specialized organ that synthesizes silk proteins. The silk gland undergoes massive degeneration during the larval to pupal stage, which involves in cell apoptosis. In this paper, high throughput sequencing was used to detect the expression of messenger RNA (mRNA), long noncoding RNA (lncRNA), and microRNA (miRNA) from silk glands of Day 3 in the fifth instar larvae (L5D3) and the spinning 36h (sp36h). We analyzed the Gene Ontology (GO) functions of target genes of the differentially expressed lncRNAs and miRNAs. We investigated the regulations of mRNA, lncRNA, and miRNA on silk gland apoptosis in L5D3 and sp36h. In total, 10,947 lncRNAs were detected in the silk gland and the index number TCONS-00021360 lncRNA may be involved in the process of apoptosis. In addition, 344 miRNAs targeted 285 mRNAs were related to the death process under GO entry. The results indicated that miRNAs play an important role in the molecular regulation of the silk gland apoptosis compared with that of lncRNAs. Finally, we screened 746 lncRNAs and 20 miRNAs that might interact with BmDredd, and drew an interaction network among them.


Assuntos
Estruturas Animais/metabolismo , Apoptose/fisiologia , Bombyx/fisiologia , RNA/metabolismo , Animais , Regulação da Expressão Gênica/fisiologia , RNA/genética
8.
J Colloid Interface Sci ; 536: 694-700, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30408689

RESUMO

Spontaneous solar-driven water splitting to generate H2 with no pollution discharge is an ideal H2 generation approach. However, its efficiency remains far from real application owing to the poor light-harvesting and ultrafast charge recombination of photocatalysts. To address these issues, herein, we employed a novel but simple chemical bath deposition (CBD) method to construct CdS/SrTiO3 nanodots-on-nanocubes at room temperature (ca. 25 °C). The as-synthesized nanohybrids not only expand light absorption from ultraviolet (UV) to visible light but also significantly retard charge recombination owing to the well-defined heterostructure formation. As a result, the CdS/SrTiO3 exhibits high photocatalytic performance with H2 evolution rate of 1322 µmol g-1 h-1, which is 2.8 and 12.2 times higher than that of pristine CdS and SrTiO3, respectively. This work provides a universal approach for the heterostructure construction, and inspired by this, higher efficient photocatalysts for H2 evolution may be developed in the near future.

9.
Med Sci Monit ; 24: 6559-6563, 2018 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-30226219

RESUMO

BACKGROUND Y chromosome microdeletions are usually de novo mutations, but in several cases, transmission from fertile fathers to infertile sons has been reported. MATERIAL AND METHODS We report 3 cases of infertile patients who inherited expanded Y chromosome microdeletions from their fathers, who carried b2/b3 subdeletion or duplication. The karyotype was analyzed using G-banding. High-throughput sequencing was used to detect AZF region microdeletions. RESULTS Cytogenetic analysis showed a normal karyotype 46,XY in patient 1 (P1), patient 2 (P2), and their fathers (F1 and F2). Patient 3 (P3) and his father (F3) presented a karyotype of 46,XY,Yqh-. High-throughput sequencing for the AZF disclosed an identical b2/b3 subdeletion in the F1 and F2. P1 had an AZFc deletion that accounted for 3.5 Mb, and P2 had an AZFa+b+c microdeletion that accounted for 10.5 Mb. F3 had a b2/b3 duplication of 1.8Mb, but P3 had an AZFb+c deletion of 6.2 Mb. CONCLUSIONS Our findings suggest that b2/b3 partial deletion or duplication can lead to structural instability in the Y chromosome and be a risk factor of complete deletion of AZFc or more expanded deletion during transmission.


Assuntos
Infertilidade Masculina/genética , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/genética , Adulto , Azoospermia/genética , Deleção Cromossômica , Cromossomos Humanos Y/genética , Humanos , Cariótipo , Masculino , Pessoa de Meia-Idade , Oligospermia/genética , Aberrações dos Cromossomos Sexuais
10.
Molecules ; 23(9)2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30201888

RESUMO

We aimed to develop new effective catalysts for the synthesis of propylene carbonate from propylene oxide and carbon dioxide. A kind of Mx+LClx coordination complex was fabricated based on the chelating tridentate ligand 2,6-bis[1-(phenylimino)ethyl] pyridine (L). The obtained products were characterized by elemental analysis, infrared spectroscopy, ultraviolet spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction. It was found that the catalytic activity of the complexes with different metal ions, the same ligand differed and co-catalyst, where the order of greatest to least catalytic activity was 2 > 3 > 1. The catalytic system composed of complex 2 and DMAP proved to have the better catalytic performance. The yields for complex 2 systems was 86.7% under the reaction conditions of 100 °C, 2.5 MPa, and 4 h. The TOF was 1026 h-¹ under the reaction conditions of 200 °C, 2.5 MPa, and 1 h. We also explored the influence of time, pressure, temperature, and reaction substrate concentration on the catalytic reactions. A hypothetical catalytic reaction mechanism is proposed based on density functional theory (DFT) calculations and the catalytic reaction results.


Assuntos
Dióxido de Carbono/química , Complexos de Coordenação/química , Compostos de Epóxi/química , Propano/análogos & derivados , Piridinas/química , Catálise , Cristalografia por Raios X , Reação de Cicloadição , Ligantes , Conformação Molecular , Propano/síntese química , Propano/química , Eletricidade Estática
11.
Sci Rep ; 8: 47004, 2018 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-30019699

RESUMO

This corrects the article DOI: 10.1038/srep28767.

12.
New Phytol ; 220(2): 567-578, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29956839

RESUMO

Kin recognition is an important mediator of interactions within individuals of a species. Despite increasing evidence of kin recognition in natural plant populations, relatively little is known about kin recognition in crop species where numerous cultivars have been generated by artificial selection. We identified rice (Oryza sativa) cultivars with the ability for kin recognition from two sets of indica-inbred and indica-hybrid lines at different levels of genetic relatedness. We then assessed this ability among kin and nonkin and tested potential mechanisms in a series of controlled experiments and field trails. Rice cultivars with the ability for kin recognition were capable of detecting the presence of kin and nonkin and responded to them by altering root behavior and biomass allocation, particularly for grain yield. Furthermore, we assessed the role of root exudates and found a root-secreted nitrogen-rich allantoin component to be responsible for kin recognition in rice lines. Kin recognition in rice lines mediated by root exudates occurs in a cultivar-dependent manner. Rice cultivars with the ability for kin recognition may increase grain yield in the presence of kin. Such an improvement of grain yield by kin recognition of cultivar mixtures offers many implications and applications in rice production.


Assuntos
Oryza/fisiologia , Biomassa , Grão Comestível , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/fisiologia
13.
Mol Cytogenet ; 11: 10, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29416565

RESUMO

Background: Balanced translocations may cause the loss of genetic material at the breakpoints and may result in failure of spermatogenesis. However, carriers of reciprocal translocation may naturally conceive. Genetic counseling of male carriers of translocations remains challenging. This study explores the clinical features of carriers of chromosome 5 translocations, enabling informed genetic counseling of these patients. Results: Of 82 translocation carriers, 9 (11%) were carriers of a chromosome 5 translocation. One case had azoospermia, while three cases had experienced recurrent spontaneous abortions, two cases had each experienced stillbirth, and three cases produced a phenotypically normal child confirmed by amniocentesis. A literature review identified 106 patients who carried chromosome 5 translocations. The most common chromosome 5 translocation was t(4,5), observed in 13 patients. Breakpoint at 5p15 was observed in 11 patients. All breakpoints at chromosome 5 were associated with gestational infertility. Conclusion: In genetic counseling, physicians should consider chromosome 5 and its breakpoints. Carriers of chromosome 5 translocations may continue with natural conception or use assisted reproductive technologies, such as preimplantation genetic diagnosis.

14.
J Int Med Res ; 46(1): 307-315, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28835195

RESUMO

Objectives To investigate azoospermic factor (AZF) microdeletions in infertile men from northeastern China with karyotypic Y chromosome abnormalities. Methods G-banding of metaphase chromosomes and karyotype analysis were performed in all infertile male patients. Genomic DNA was isolated and used to analyze classical AZF microdeletions by PCR. The regions and sequence-tagged sites of AZFa (SY86, SY84), AZFb (SY127, SY134, SY143), and AZFc (SY152, SY254, SY255, SY157) were sequenced by multiplex PCR. Results A total of 190 Y chromosome abnormality carriers were found, of whom 35 had AZF microdeletions. These were most common in 46,X,Yqh- patients, followed by 45,X/46,XY patients. Most microdeletions were detected in the AZFb + c region, including 48.57% of all AZF microdeletion cases. AZF partial deletions were also seen in these patients. Overall, AZF microdeletions were detected in 38.5% Y chromosome abnormality carriers, and most were observed in 46,X,Yqh- individuals. Loss of SY152 was seen in all 35 patients, with SY254/SY255 detected in 34 of 35 patients. Conclusions AZF microdeletions were detected in 38.5% of Y chromosome abnormality carriers. This indicates that AZF microdeletion screening is advisable for individuals with karyotypic Y chromosome abnormalities.


Assuntos
Azoospermia/genética , Deleção Cromossômica , Cromossomos Humanos Y , Oligospermia/genética , Adulto , Azoospermia/diagnóstico , Azoospermia/patologia , China , Humanos , Infertilidade Masculina , Cariótipo , Masculino , Oligospermia/diagnóstico , Oligospermia/patologia , Reação em Cadeia da Polimerase , Análise do Sêmen
15.
16.
World J Gastroenterol ; 23(13): 2308-2317, 2017 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-28428710

RESUMO

AIM: To investigate the mechanism of chaperone-mediated autophagy (CMA)-induced resistance to irradiation-triggered apoptosis through regulation of the p53 protein in hepatocellular carcinoma (HCC). METHODS: Firstly, we detected expression of lysosome-associated membrane protein 2a (Lamp-2a), which is the key protein of CMA, by western blot in HepG2 and SMMC7721 cells after irradiation. We further used shRNA Lamp-2a HCC cells to verify the radioresistance induced by CMA. Next, we detected the HMGB1 and p53 expression after irradiation by western blot, and we further used RNA interference and ethyl pyruvate (EP), as a HMGB1 inhibitor, to observe changes of p53 expression. Finally, an immunoprecipitation assay was conducted to explore the interaction between Lamp-2a and HMGB1, and the data were analyzed. RESULTS: We found the expression of Lamp-2a was increased on irradiation while apoptosis decreased in HepG2 and SMMC7721 cells. The apoptosis was increased markedly in the shRNA Lamp-2a HepG2 and SMMC7721 cells as detected by western blot and colony formation assay. Next, we found p53 expression was gradually reduced on irradiation but obviously increased in shRNA Lamp-2a cells. Furthermore, p53 increased the cell apoptosis on irradiation in Hep3B (p53-/-) cells. Finally, p53 levels were regulated by HMGB1 as measured through RNA interference and the EP treatment. HMGB1 was able to combine with Lamp-2a as seen by immunoprecipitation assay and was degraded via the CMA pathway. The decreased HMGB1 inhibited p53 expression induced by irradiation and further reduced the apoptosis in HCC cells. CONCLUSION: CMA pathway activation appears to down-regulate the susceptibility of HCC to irradiation by degrading HMGB1 with further impact on p53 expression. These findings have clinical relevance for radiotherapy of HCC.


Assuntos
Autofagia , Carcinoma Hepatocelular/metabolismo , Proteína HMGB1/metabolismo , Neoplasias Hepáticas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Carcinoma Hepatocelular/radioterapia , Células Hep G2 , Humanos , Neoplasias Hepáticas/radioterapia , Tolerância a Radiação
17.
Infect Dis Poverty ; 5(1): 74, 2016 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-27491387

RESUMO

BACKGROUND: The Ebola virus disease spread rapidly in West Africa in 2014, leading to the loss of thousands of lives. Community engagement was one of the key strategies to interrupt Ebola transmission, and practical community level measures needed to be explored in the field and tailored to the specific context of communities. METHODS: First, community-level education on Ebola virus disease (EVD) prevention was launched for the community's social mobilizers in six districts in Sierra Leone beginning in November 2014. Then, from January to May of 2015, in three pilot communities, local trained community members were organized to engage in implementation of EVD prevention and transmission interruption measures, by involving them in alert case report, contact tracing, and social mobilization. The epidemiological indicators of transmission interruption in three study communities were evaluated. RESULTS: A total of 6 016 community social mobilizers from 185 wards were trained by holding 279 workshops in the six districts, and EVD message reached an estimated 631 680 residents. In three pilot communities, 72 EVD alert cases were reported, with 70.8 % of them detected by trained local community members, and 14 EVD cases were finally identified. Contact tracing detected 64.3 % of EVD cases. The median duration of community infectivity for the cases was 1 day. The secondary attack rate was 4.2 %, and no third generation of infection was triggered. No health worker was infected, and no unsafe burial and noncompliance to EVD control measures were recorded. The community-based measures were modeled to reduce 77 EVD cases, and the EVD-free goal was achieved four months earlier in study communities than whole country of Sierra Leone. CONCLUSIONS: The community-based strategy of social mobilization and community engagement was effective in case detection and reducing the extent of Ebola transmission in a country with weak health system. The successfully practical experience to reduce the risk of Ebola transmission in the community with poor resources would potentially be helpful for the global community to fight against the EVD and the other diseases in the future.


Assuntos
Surtos de Doenças/prevenção & controle , Ebolavirus/fisiologia , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Doença pelo Vírus Ebola/transmissão , Doença pelo Vírus Ebola/virologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Serra Leoa/epidemiologia , Adulto Jovem
18.
Sci Rep ; 6: 28767, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-27357865

RESUMO

A novel quantum key distribution protocol is presented, based on entanglement and dense coding and allowing asymptotically secure key distribution. Considering the storage time limit of quantum bits, a grouping quantum key distribution protocol is proposed, which overcomes the vulnerability of first protocol and improves the maneuverability. Moreover, a security analysis is given and a simple type of eavesdropper's attack would introduce at least an error rate of 46.875%. Compared with the "Ping-pong" protocol involving two steps, the proposed protocol does not need to store the qubit and only involves one step.

19.
Dalton Trans ; 45(29): 11628-32, 2016 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-27332080

RESUMO

Two organic-inorganic hybrid pillared-layer lanthanide borates, [Ln2B8O12(bdc)3(H2O)]·H2O (Ln = Pr, 1; Nd, 2; H2bdc = 1,4-benzene dicarboxylic acid), have been made, in which inorganic layers are built by Ln-centred oxoboron ring clusters, Ln@B12O28/Ln@B12O29, while the pillars are organic bdc linkers. Interestingly, two types of linkages, Ln-O-C and B-O-C bonds, exist in the structures, showing firstly novel linking modes between inorganic polyborate and organic dicarboxylate.

20.
Dalton Trans ; 45(30): 11958-67, 2016 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-27273263

RESUMO

Six new lanthanide (Ln) germanate cluster organic frameworks (LnGeCOFs) derived from {Ln8Ge12} cage cluster units {[Nd(pza)2(H2O)] [Nd8Ge12(µ3-O)24E12(pza)(H2O)12]}·3H2O (1), {[Dy(CH3COO)(CO3)(H2O)]2[Dy8Ge12(µ3-O)24E12(H2O)12]}·11H2O (2), {[TbGeE(HO)2O(pza) (H2O)]2[Tb8Ge12(µ3-O)24E12(H2O)6]}·18H2O (3), {[DyGeE(HO)2O(C3H5NO2)(H2O)]2[Dy8Ge12(µ3-O)24E12(H2O)8]}·8H2O (4), {[Tb(pca)2 (H2O)]3[Tb8Ge12(µ3-O)24E12(H2O)4]}·(OH)3·10H2O (5) and {[Dy(pza)2(H2O)][Dy(pza)2(H2O)2][Dy(pza)3(H2O)][Dy8Ge12(µ3-O)24E12(pza)(HCOO) (H2O)6]}·5H2O (6) have been hydrothermally synthesized and structurally characterized. Increasing the amount of the second ligands can induce not only the assembly from 1 to 5, 6 based on Ln oxides as the starting sources, but also the assembly from 2 to 3, 4 based on Ln salts as the starting sources. The successful preparation of these LnGeCOFs suggests the importance of the second ligands in the structural construction of 1-6. To our knowledge, 1 is the first example that includes right- and left-handed helical chains among LnGeCOFs based on bis(carboxyethylgermanium)sesquioxide. 2, 4 and 6 are the first dysprosium incorporated organogermanates based on bis(carboxyethylgermanium)sesquioxide. 4 and 5 display very open framework structures with a solvent-accessible volume of 34.6% for 4 and 35.0% for 5. Moreover, the solid-state photoluminescence properties of 1, 3 and 5 have been investigated at room temperature and they exhibit the characteristic emission bands derived from Ln cations.

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