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1.
Dalton Trans ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39373196

RESUMO

Qudits are anticipated to streamline quantum computation by minimizing iterations, lowering error rates, and facilitating error correction. It has been shown that Dy(III)-based molecular systems can act as qudits with expanded Hilbert spaces. Achieving a robust intramolecular interaction, whether exchange or dipolar, is crucial for spanning the Hilbert space of qudits; hence, short Dy(III)⋯Dy(III) distances are required. Looking for multilevel systems that can be employed as qudits, we have synthesized and characterized two dysprosium-based isotopologues: [163Dy2(BTFA)4(PHZP)2]0 (1(I=5/2)) and [164Dy2(BTFA)4(PHZP)2]0 (2(I=0)), where BTFA = 3-benzoyl-1,1,1-trifluoroacetone and PHZP = N'-[(E)-(pyrazin-2-yl)methylidene]pyrazine-2-carbohydrazonate. Both complexes showed slow magnetic relaxation at zero applied magnetic field. µSQUID investigations, at milli-Kelvin temperatures, and direct and alternating current magnetic measurements reveal distinctions in the magnetic behavior between the two complexes and an operative interaction between the Dy(III) centers. We find that the presence or absence of the nuclear spin plays a minor role in the magnetic properties above 2 K. On the contrary, at milli-Kelvin temperatures, µSQUID studies show enhanced relaxation in 1(I=5/2), attributed to several quantum tunnelling pathways enabled by hyperfine and quadrupole interactions. The interplay between the antiferromagnetic coupling and enhanced relaxation indicates that the exchange coupling influences the relaxation mechanisms at different temperature ranges.

2.
RSC Adv ; 14(32): 23023-23036, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39040701

RESUMO

Aqueous zinc ion batteries (AZIBs) have garnered considerable interest as an eco-friendly, safe, and cost-effective energy storage solution. Although significant strides have been made in recent years, there remain technical hurdles to overcome. Herein, this review summarizes in detail the primary challenges confronting aqueous zinc ion batteries, including the rampant dendrite growth, and water-induced parasitic reactions, and proposes host-engineering modification strategies focusing on optimizing the structure design of the zinc anode substrates, involving three-dimensional structure design, zincophilicity regulation, and epitaxial-oriented modification, and comprehensively analyzes the structure-activity relationship between different modification strategies and battery performance. In addition, we highlight the research trends and prospects in future anode modification for aqueous zinc-ion batteries. This work offers valuable insights into advanced Zn anode constructions for further applications in high-performance AZIBs.

3.
J Alzheimers Dis ; 99(3): 1005-1022, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38759013

RESUMO

Background: Alzheimer's disease (AD) is a progressive neurodegeneration disease. Physical activity is one of the most promising modifiable lifestyles that can be effective in slowing down the progression of AD at an early stage. Objective: Explore the molecular processes impaired in AD that were conversely preserved and enhanced by physical activity. Methods: Integrated transcriptomic analyses were performed in datasets that contain AD patients and elders with different degrees of physical activity. The changes of the hub genes were validated through analyzing another two datasets. The expression of the hub genes was further detected in the hippocampus and cortexes of APP/PS1 transgenic mice with or without physical activity by Quantitative polymerase chain reaction (qPCR). Results: Cross-comparison highlighted 195 DEGs displaying opposed regulation patterns between AD and high physical activity (HPA). The common DEGs were predominantly involved in synaptic vesicle recycling and synaptic transmission, largely downregulated in AD patients but upregulated in the elders with HPA. Two key modules and four hub genes that were related to synaptic vesicle turnover were obtained from the PPI network. The expression of these hub genes (SYT1, SYT4, SH3GL2, and AP2M1) was significantly decreased in AD transgenic mice and was reversed by HPA training. Conclusions: HPA may reverse AD pathology by upregulating a range of synaptic vesicle transport related proteins which might improve the efficiency of synaptic vesicle turnover and facilitate inter-neuronal information transfer. The study provides novel insights into the mechanisms underlining the protective effects of HPA on AD.


Assuntos
Doença de Alzheimer , Camundongos Transgênicos , Transmissão Sináptica , Doença de Alzheimer/genética , Animais , Humanos , Camundongos , Transmissão Sináptica/fisiologia , Exercício Físico/fisiologia , Hipocampo/metabolismo , Precursor de Proteína beta-Amiloide/genética , Masculino , Sinapses/patologia , Feminino , Presenilina-1/genética , Perfilação da Expressão Gênica , Idoso
4.
Angew Chem Int Ed Engl ; 63(17): e202401372, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38390783

RESUMO

Herein, we present the first report on the synthesis of rare-earth complexes featuring a 9,10-diborataanthracene ligand. This 14-π-electron ligand is highly reductive and was previously used in small-molecule activation. Salt elimination reactions between dipotassium 9,10-diethyl-9,10-diborataanthracene [K2(DEDBA)] and [LnIII(η8-CotTIPS)(BH4)(thf)x] (CotTIPS=1,4-(iPr3Si)2C8H6) in a 1 : 1 ratio yielded heteroleptic sandwich complexes [K(η8-CotTIPS)LnIII(η6-DEDBA)] (Ln=Y, Dy, Er). These compounds form Lewis-base-free one-dimensional coordination polymers when crystallised from toluene. In contrast, reaction of [K2(DEDBA)] and [LnIII(η8-CotTIPS)(BH4)(thf)x] in a 1 : 2 ratio led to the formation of heteroleptic triple-decker complexes [(η8-CotTIPS)LnIII(µ-η6:η6-DEDBA)LnIII(η8-CotTIPS)] (Ln=Y, Dy, Er). Notably, these are not only the first lanthanide triple-decker compounds featuring a six-membered ring as a deck but also the first trivalent lanthanide triple-decker featuring a heterocycle in the coordination sphere. Magnetic investigations reveal that [K(η8-CotTIPS)LnIII(η6-DEDBA)] (Ln=Dy, Er) and [(η8-CotTIPS)ErIII(µ-η6:η6-DEDBA)ErIII(η8-CotTIPS)] exhibit Single-Molecule Magnet (SMM) behaviour. In the case of [(η8-CotTIPS)LnIII(µ-η6:η6-DEDBA)LnIII(η8-CotTIPS)] (Ln=Dy, Er), the introduction of a second near lanthanide ion results in strong antiferromagnetic interactions, allowing the enhancement of the magnetic characteristic of the system, compared to the quasi isolated counterpart. This research renews the overlooked coordination chemistry of the DBA ligand and expands it to encompass rare-earth elements.

5.
Chem Sci ; 15(4): 1338-1347, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38274072

RESUMO

Synthesis and characterization of Lewis base free coordination polymers of selected lanthanides are presented. For this purpose, the substituted CotTIPS ligand (CotTIPS = 1,4-bis-triisopropylsilyl-cyclo-octatetraendiide) was used to synthesize homoleptic, anionic multidecker compounds of the type [K{LnIII(ɳ8-CotTIPS)2}]n. Depending on the solvent used for crystallization and the ionic radii of the lanthanide cations, three different categories of one-dimensional heterobimetallic coordination polymers were obtained in the solid state. For the early lanthanides La and Ce a unique helical conformation was obtained by crystallization from toluene, while the ionic radius of Pr seems to be a turning point towards the crystallization of zigzag polymers. For Er a third structural motif, a trapezoidal wave polymer was observed. Additionally, the zigzag polymer for all compounds could be obtained by changing the solvent from toluene to Et2O, reavealing a correlation between solid-state structure and ionic radii as well as solvent. While photoluminescence (PL) properties of Cot-lanthanide compounds are scarce, the La complexes show ligand centered green luminescence, whereas the Ce complexes reveal deep red emission origin from d-f transitions. The Er-compounds are single-molecule magnets, in which the magnetic relaxation of each Er ion occurs isolated from its neighbors at temperatures above 10 K, while below 9 K a strong antiferromagnetic coupling between the Er ions was seen.

6.
Inorg Chem ; 62(37): 15148-15156, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37655998

RESUMO

Single-molecule magnets are molecular complexes proposed to be useful for information storage and quantum information processing applications. In the quest for multilevel systems that can act as Qudits, two dysprosium-based isotopologues were synthesized and characterized. The isotopologues are [164Dy2(tmhd)6(tape)] (1(I=0)) and [163Dy2(tmhd)6(tape)] (2(I=5/2)), where tmhd = 2,2,6,6-tetramethylheptandionate and tape = 1,6,7,12-tetraazaperylene. Both complexes showed slow relaxation at a zero applied magnetic field with dominant Orbach and Raman relaxation mechanisms. µSQUID studies at milli-Kelvin temperatures reveal quasi-single ion loops, in contrast with the expected S-shape (near zero field) butterfly loops, characteristic of antiferromagnetically coupled dimeric complexes. Through analysis of the low-temperature data, we find that the interaction operating between Dy(III) is small, leading to a small exchange biasing from the zero-field transition. The resulting indirectly coupled nuclear states are degenerate or possess a small energy difference between them. We, therefore, conclude that for the creation of Qudits with enlarged Hilbert spaces, shorter Dy(III)···Dy(III) distances are deemed essential.

7.
Rev. bras. med. esporte ; Rev. bras. med. esporte;29: e2022_0641, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1423299

RESUMO

ABSTRACT Introduction: Blood flow restriction therapy, also known as KAATSU pressurization training or ischemic exercise training is a controlled method of vascular occlusion combined with resistance training, with the great growth of its research in recent years. Regular strength training, prevention of lean mass loss, and post-operative rehabilitation are some areas in which the therapy has been prominent. It is believed that it can also be beneficial in sports performance. Objective: Study the effects of an intervention with blood flow restriction therapy on athletes during training. Methods: 32 college athletes with more than two years of experience in sports training, free of injuries, and 20±3 years old were volunteers. They were randomly divided into groups A (no pressure), B (training pressure), C (intermittent pressure), D (full compression). Results: The athletes in the no pressurization group, intermittent pressurization group, training pressurization group, and full-time pressurization group showed significant differences (P<0.05). It can be considered that there is a significant difference in the muscular endurance indexes of the athletes in the non-compression group before and after training, while the athletes in the non-compression group achieved a significant increase in muscular endurance after 6 weeks of training Conclusion: Blood flow restriction therapy can effectively enhance the training effect with various strength qualities, and play a role as a promoter of hypertrophy and vascularization. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.


RESUMO Introdução: A terapia de restrição do fluxo sanguíneo, também conhecida como treinamento de pressurização da KAATSU ou treinamento de exercício isquêmico é um método controlado de oclusão vascular combinado ao treino de resistência, com grande crescimento de suas pesquisas nos últimos anos. Treinos regulares de força, prevenção de perda de massa magra e reabilitação pós-operatória são algumas áreas em que a terapia tem se destacado. Acredita-se que possa ser benéfica também no desempenho esportivo. Objetivo: Estudar os efeitos de uma intervenção com terapia de restrição do fluxo sanguíneo nos atletas durante o treinamento. Métodos: Foram voluntários 32 atletas universitários com mais de dois anos de experiência em treinamento esportivo, livres de lesões e com 20±3 anos de idade. Foram divididos aleatoriamente em grupos A (sem pressão), B (pressão de treinamento), C (pressão intermitente), D (compressão integral). Resultados: Os atletas do grupo sem pressurização, do grupo de pressurização intermitente, do grupo de pressurização de treinamento e do grupo de pressurização em tempo integral, mostraram diferenças significativas (P<0,05). Pode-se considerar que existe uma diferença significativa nos índices de resistência muscular dos atletas do grupo sem compressão antes e depois do treinamento, enquanto os atletas do grupo sem compressão conseguiram um aumento significativo na resistência muscular após 6 semanas de treinamento Conclusão: A terapia de restrição do fluxo sanguíneo pode efetivamente melhorar o efeito de treinamento com várias qualidades de força, além de desempenhar um papel como promotor de hipertrofia e vascularização. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.


RESUMEN Introducción: La terapia de restricción del flujo sanguíneo, también conocida como entrenamiento de presurización KAATSU o entrenamiento de ejercicio isquémico es un método controlado de oclusión vascular combinado con entrenamiento de resistencia, con gran crecimiento de su investigación en los últimos años. El entrenamiento regular de la fuerza, la prevención de la pérdida de masa magra y la rehabilitación postoperatoria son algunas de las áreas en las que la terapia se ha destacado. Se cree que también puede ser beneficioso para el rendimiento deportivo. Objetivo: Estudiar los efectos de una intervención con terapia de restricción del flujo sanguíneo en atletas durante el entrenamiento. Métodos: 32 atletas universitarios con más de dos años de experiencia en el entrenamiento deportivo, libres de lesiones y con 20±3 años de edad fueron voluntarios. Se dividieron aleatoriamente en los grupos A (sin presión), B (presión de entrenamiento), C (presión intermitente), D (compresión total). Resultados: Los atletas del grupo sin presurización, del grupo con presurización intermitente, del grupo con presurización de entrenamiento y del grupo con presurización a tiempo completo mostraron diferencias significativas (P<0,05). Se puede considerar que existe una diferencia significativa en los índices de resistencia muscular de los atletas del grupo sin compresión antes y después del entrenamiento, mientras que los atletas del grupo sin compresión lograron un aumento significativo de la resistencia muscular después de 6 semanas de entrenamiento Conclusión: La terapia de restricción del flujo sanguíneo puede mejorar eficazmente el efecto del entrenamiento con diversas cualidades de fuerza, y desempeñar un papel como promotor de la hipertrofia y la vascularización. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

8.
Front Physiol ; 13: 1060640, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36569754

RESUMO

The study aimed to investigate the effect of flywheel accentuated eccentric loading (AEL) training on the running economy (RE) of young male well-trained distance runners. Twenty-two runners participated and were randomly assigned to the flywheel (FG, n = 12) and the control group (CG, n = 10). Traditional endurance training was performed in both groups three times a week for 6-week, while traditional resistance and flywheel AEL training was added to the CG and FG respectively. Subjects performed the incremental exercise test, squat jump, and countermovement jump (CMJ) before and after training. The results showed that 1) the RE at 65% of peak oxygen consumption (VO2peak), 75% VO2peak, and 85% VO2peak improved significantly after 6 weeks of training (p < 0.01, Effect size (ES) = 0.76; p < 0.01, ES = 1.04; p < 0.01, ES = 1.85) in FG, and the RE of 85% VO2peak in FG was significantly lower than CG (p < 0.05, ES = 0.30); 2) in post-training, both squat jump (p < 0.01, ES = 0.73) and CMJ (p < 0.01, ES = 1.15) performance, eccentric utilization ratio (p < 0.04, ES = 0.44), the rate of force development (RFD) of squat jump (p < 0.05, ES = 0.46), and CMJRFD (p < 0.01, ES = 0.66) were significantly improved in FG. And there are no significant differents in CG group because it was maintain training for our participants. Our findings showed that 1) flywheel AEL training improves the muscles' explosive strength and other neuromuscular functions, and improves the athlete's running economy under 65%, 75%, and 85% VO2peak, which potentially increases endurance performance. 2) Flywheel AEL training can improve the height, RFD, and the eccentric utilization ratio of squat jump and CMJ, and other lower limb elastic potential energy indicators of the young male, well-trained distance runners.

9.
Front Genet ; 11: 534, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32595697

RESUMO

BACKGROUND: Alternative splicing (AS) is important in the regulation of gene expression and aberrant AS is emerging as a major factor in the pathogenesis of human conditions, including cancer. Triple-negative breast cancer (TNBC) is the most challenging subtype of breast cancer with strong invasion, high rate of metastasis, and poor prognosis. Here we report a systematic profiling of aberrant AS in TNBC. METHODS: The percent spliced in (PSI) values for AS events in 151 TNBC patients were obtained from The Cancer Genome Atlas (TCGA) SpliceSeq database. Univariate Cox and stepwise Multivariate Cox regression analyses were conducted to find the best prognostic AS model. Splicing regulatory networks were constructed by prognosis-related spliceosome and aberrant AS events. Additionally, pathway enrichment and gene set enrichment analysis (GSEA) were further employed to reveal the significant pathways for prognosis-related AS genes. Finally, splicing regulatory networks were constructed via Spearman's rank correlation coefficients between prognosis-related AS events and splicing factor expressions. RESULTS: A total of 1,397 prognosis-associated AS events were identified in TNBC. The majority of the parent genes of prognostic AS events exhibited direct interactions to each other in the STRING gene network. Pathways of focal adhesion (p < 0.001), RNA splicing (p = 0.007), homologous recombination (p = 0.042) and ECM-receptor interaction (p = 0.046) were found to be significantly enriched for prognosis-related AS. Additionally, the area under curve (AUC) of the best AS prognostic predictor model reached 0.949, showing a powerful capability to predict outcomes. The Exon Skip (ES) type of AS events displayed more robust and efficient capacity in predicting performance than any other specific AS events type in terms of prognosis. The ES AS signature might confer a strong oncogenic phenotype in the high-risk group with elevated activities in cell cycle and SUMOylating pathways of tumorigenesis, while programmed cell death and metabolism pathways were found to be enriched in the low-risk group of TNBC. The splicing correlation network also revealed a regulatory mode of prognostic splicing factors (SFs) in TNBC. CONCLUSION: Our analysis of AS events in TNBC could not only contribute to elucidating the tumorigenesis mechanism of AS but also provide clues to uncovering underlying prognostic biomarkers and therapeutic targets for further study.

10.
Adv Mater ; 32(17): e2000151, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32159890

RESUMO

Structural modulation endows electrochemical hybrids with promising energy storage properties owing to their adjustable interfacial and/or electronic characteristics. For MXene-based materials, however, the facile but effective strategies for tuning their structural properties at nanoscale are still lacking. Herein, 3D crumpled S-functionalized Ti3 C2 Tx substrate is rationally integrated with Fe3 O4 /FeS heterostructures via coprecipitation and subsequent partial sulfurization to induce a highly active and stable electrode architecture. The unique heterostructures with tuned electronic properties can induce improved kinetics and structural stability. The surface engineering by S terminations on the MXene further unlocks extra (pseudo)capacitive lithium storage. Serving as anode for lithium storage, the optimized electrode delivers an excellent long-term cycling stability (913.9 mAh g-1 after 1000 cycles at 1 A g-1 ) and superior rate capability (490.4 mAh g-1 at 10 A g-1 ). Moreover, the (de)lithiation pathways associated with energy storage mechanisms are further revealed by operando X-ray diffraction, in situ electroanalytical techniques, and first-principles calculations. The hybrid electrode is proved to undergo stepwise phase transformations during discharging but a relatively uniform reconversion during charging, suggesting an asymmetric conversion mechanism. This work provides a novel strategy for designing high-performance hybrids and paves the way for in-depth understanding of complex lithium intercalation and conversion reactions.

11.
ACS Nano ; 13(10): 12219-12229, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31589407

RESUMO

Silicon (Si), a promising candidate for next-generation lithium-ion battery anodes, is still hindered by its volume change issue for (de)lithiation, thus resulting in tremendous capacity fading. Designing carbon-modified Si materials with a void-preserving structure (Si@void@C) can effectively solve this issue. The preparation of Si@void@C, however, usually depended on template-based routes or chemical vapor deposition, which involve toxic reagents, tedious operation processes, and harsh conditions. Here, a facile templateless approach for preparing Si@void@C materials is reported through controlling the growth kinetics of resin, without the use of toxic hydrofluoric acid or harsh conditions. This approach allows great flexibility in tuning the crucial parameters of Si@void@C, such as the carbon shell thickness, the reserved void size, and the number of Si cores coated by a carbon shell. The optimized Si@void@C delivers a large specific capacity (1993.2 mAh g-1 at 0.1 A g-1), excellent rate performance (799.4 mAh g-1 at 10.0 A g-1), and long cycle life (73.5% capacity retention after 1000 cycles at 2.0 A g-1). In addition, a full cell fabricated with a Si@void@C anode and commercial LiFePO4 cathode also displays an impressive cycling performance.

12.
BMC Public Health ; 19(1): 1220, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31484512

RESUMO

BACKGROUND: Health literacy is defined as the cognitive and social skills that determine the motivation and ability of individuals to gain access to, understand and use information in ways that promote and maintain good health. A Health Literacy Questionnaire (HLQ) is a toolkit with good reliability and validity. Accordingly, this study administered HLQ among older adults in China to examine its factor structure, reliability, homogeneity, and discriminant validity for use in understanding better the health literacy of older adults and determining corresponding measures. METHODS: Psychometric properties were examined based on the data collected via face-to-face interviews (N = 343). Tests included the difficulty level, composite scale reliability, confirmatory factor analysis (CFA), and Bayesian structural equation modeling (BSEM). RESULTS: The easiest scale to obtain a high score was "Social support for health" and the hardest, "Navigating the health care system" and "Appraisal of health information." Two one-factor models fitted well with no correlated residuals allowed. After model modification, the CFA fit statistics of the other seven scales were good. All HLQ scales were found to be homogenous, with a composite reliability ranging from 0.74 to 0.85. The nine-factor Bayesian structural equation model fitted the data well (Posterior-Predictive-P value = 0.670; 95% Confidence Interval for the difference between the observed and replicated Chi-square values = - 163.320, 102.750). CONCLUSIONS: The Chinese version of the HLQ has strong construct and content validity and high composite reliability when applied to older adults in Changsha City, China. Therefore, the nine-scale HLQ can now be administered to Chinese older adults, thereby providing a powerful approach to understanding the multidimensional area of health literacy.


Assuntos
Letramento em Saúde/estatística & dados numéricos , Inquéritos e Questionários , Idoso , Teorema de Bayes , China , Estudos Transversais , Análise Fatorial , Humanos , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes
13.
Nanoscale ; 11(9): 3933-3944, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30762053

RESUMO

LiMnxFe1-xPO4 (LMFP) has attracted extensive interest owing to its high safety and appropriate redox potential. Nevertheless, its poor electrochemical kinetics and structural instability, depending on its manganese content, are still limiting its further application. Herein, we realize a concentration-gradient LiMn0.5Fe0.5PO4 hollow sphere cathode material with a carbon coating (HCG-LMFP/C) by a facile and controllable two-step solvothermal approach. On the one hand, the porous hollow architecture can sustain excellent structural stabilization against the volume changes that occur during repeated Li+ intercalation/deintercalation. On the other hand, the unique concentration-gradient structure with its Fe-rich surface can not only relieve interface deterioration and improve the ionic/electric conductivity due to the active nature of LiFePO4, but also guarantees the chemical stability of the LMFP against electrolyte attack and remarkably reduces Mn dissolution, even at elevated temperature. Therefore, the obtained concentration-gradient HCG-LMFP/C cathode shows improved high-rate performance (111 and 78 mA h g-1 at 20 and 60C rates, respectively) and excellent capacity retention (96% after 1000 cycles at the 10C rate) as well as outstanding temperature tolerance (over a temperature range from 40 °C to -10 °C). More importantly, the present gradient strategy opens up a new window for designing high-performance and stable olivine cathodes, which could also be compatible with many other energy-storage materials for various applications.

14.
Inorg Chem ; 58(1): 594-602, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30525545

RESUMO

Three new cadmium(II) tartratoborates, namely, Cd5[(C4H2O6)2B]2(H2O)8·3H2O (1), K2Cd4[(C4H2O6)2B]2(H2O)2 (2), and Li0.92K1.08Cd1.5[(C4H2O6)2B](H2O)2 (3), have been successfully synthesized by the hydrothermal method. Compounds 1-3 belong to centric C2/ c, acentric Pc, and the polar C2, respectively. Through based on the same hybrid borate-tartrate [(C4H2O6)2B]5- anions, they exhibit different structures. The [(C4H2O6)2B]5- anion is composed of two tartrate anions and a B(OH)4- unit. Compound 1 features a novel 3D network formed by 2D {Cd3[(C4H2O6)2B]2(H2O)2}4- anionic layers and [Cd2O10] dimers, forming tunnels of large 14-MRs which are filled by the non-coordination water molecules. Compound 2 has a characteristic 3D network based on {Cd2[(C4H2O6)2B]}- units interlinked via carboxylate groups, forming tunnels of 11-MRs, half of which stuffed with the K+ ions. Compound 3 features 2D {Cd4[(C4H2O6)4B]}3+ layers which are separated by K/Li ions. Luminescent studies suggest that they emit blue light. Compounds 2 and 3 display phase-matchable second harmonic generation signs of about 3.2× and 1.5× KH2PO4, respectively.

15.
Eur J Med Chem ; 156: 800-814, 2018 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-30055465

RESUMO

A number of 5-arylisatin derivatives were synthesized in 5-6 steps from readily available starting materials. Their structures were confirmed by 1H NMR and 13C NMR as well as LC/MS. The cytotoxicity of these novel isatins against human leukemia K562 cells were evaluated by MTT assay in vitro. SAR studies indicated that the N-substituted benzyl and C-5 substituted phenyl groups greatly enhance their cytotoxic activity, whereas an intact carbonyl functionality on C-3 present in the parent ring is required to maintain such a potency. Particularly, N-(p-methoxybenzyl)-5-(p-methoxyphenyl)isatin (compound 2m) showed the highest antitumor activity against K562 cell lines (IC50 = 0.03 µM). Moreover, treatment with compound 2m significantly inhibited liver cancer HepG2 cells proliferation and migration, which could also reduce the human umbilical vein endothelial cells (HUVEC) tube formation. In conclusion, compound 2m exhibited very good cancer cells proliferation inhibition by angiogenesis responses in vitro, and 2m might be a promising angiogenesis inhibitor for cancer treatment.


Assuntos
Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Isatina/química , Isatina/farmacologia , Inibidores da Angiogênese/síntese química , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana , Humanos , Isatina/síntese química , Células K562 , Leucemia/tratamento farmacológico , Leucemia/metabolismo , Leucemia/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia
16.
Dalton Trans ; 46(22): 7361-7368, 2017 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-28548181

RESUMO

Two novel tartratoborates, namely, K2[(C4H2O6)(B3O4H)](H2O) (1) and KCu2[(C4H2O6)2B](H2O)2.5 (2), have been successfully synthesized by solvothermal reactions. They feature different kinds of structural types based on hybrid borate-tartrate motifs. The structure of compound 1 features a 3D network composed of novel [(C4H2O6)2(B3O4H)2]4- anionic groups interconnected by K+ cations. The [(C4H2O6)2(B3O4H)2]4- anion was formed by the condensation of two (B3O8H)6- groups and two tartrate anions, and such condensation reaction has never been reported previously. Compound 2 exhibits a novel 3D network structure in which 2D {Cu2[(C4H2O6)2B](H2O)2}- layers are further interconnected via K+ ions. The [(C4H2O6)2B]5- anion was formed by the condensation of two tartrate anions with a B(OH)4- unit. Magnetic measurements reveal a dominant antiferromagnetic interaction between neighboring Cu2+ ions in compound 2. Furthermore, UV-vis and infrared spectra and thermal analyses were also performed.

17.
Appl Microbiol Biotechnol ; 99(22): 9417-26, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26231135

RESUMO

For the purpose of improving the fungal production of flavonoids, the influence of naphthaleneacetic acid (NAA) and coumarin on flavonoid production by fungus Phellinus sp. P0988 was investigated by developing the corresponding kinetics of flavonoid production in a 7-L bioreactor. Phellinus sp. was confirmed to form flavonoids in pellets and broth when cultivated in basic medium, and the optimum concentration of NAA and coumarin in medium for flavonoid production were determined to be 0.03 and 0.02 g/L, respectively. The developed unstructured mathematical models were in good agreement with the experimental results with respect to flavonoid production kinetic profiles with NAA and coumarin supplementation at optimum levels and revealed significant accuracy in terms of statistical consistency and robustness. Analysis of these kinetic processes indicated that NAA and coumarin supplementations imposed a stronger positive influence on flavonoid production and substrate consumption compared to their effects on cell growth. The separate addition of NAA and coumarin resulted in enhancements in final product accumulation and productivity, achieving final flavonoid concentrations of 3.60 and 2.75 g/L, respectively, and glucose consumption showed a significant decrease compared to the non-supplemented control as well. Also, the separate presence of NAA and coumarin respectively decreased maintenance coefficients (M s) from 2.48 in the control to 1.39 and 0.22, representing decreases of 43.9 and 91.1 %, respectively. The current study is the first known application of mathematical kinetic models to explore the influence of medium components adding on flavonoid production by fungi.


Assuntos
Basidiomycota/metabolismo , Cumarínicos/farmacologia , Flavonoides/biossíntese , Ácidos Naftalenoacéticos/farmacologia , Basidiomycota/química , Basidiomycota/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Flavonoides/química , Glucose/metabolismo , Cinética , Modelos Teóricos
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