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1.
Chemistry ; 28(64): e202202651, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36124852

RESUMO

Group 14 endohedral clusters containing a metal center inside usually possess a single cage topological structure, but here an unexpected single-metal-filled double-cage cluster, [Pt@Sn17 ]4- (1 a) is reported. It can be seen as a combination of the more extended Pt-filled [Pt@Sn9 ] cage and hollow [Sn9 ] cage sharing a central Sn atom, which is offset from the central position. This double-cage species represents the largest group 14 intermetalloid cluster encapsulating a single transition metal atom. DFT calculations show that the capsule-like architecture of [Sn17 ]4- , similar to that found in [Pt2 @Sn17 ]4- , is unstable if filled with a single Pt atom and collapses to the title cluster 1 a upon geometry optimization. Deviation of the central Sn atom occurs due to the vibronic coupling as a consequence of pseudo-Jahn-Teller distortion leading to the bent Cs -symmetrical structure, in contrast to the more symmetrical D2d cage previously reported in [Ni2 @Sn17 ]4- .

2.
Angew Chem Int Ed Engl ; 60(18): 9990-9995, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33682237

RESUMO

Since [Sn8 ]6- was discovered from the solid-state phase in 2000, its solution chemistry has been elusive due to the high charges and chemical activity. Herein, we report the synthesis and characterization of an inverse sandwich-type cluster dimer {[K2 ZnSn8 (ZnMes)]2 }4- (1 a), in which the highly charged [Sn8 ]6- is captured by mixed-valence ZnI /ZnII to form the dimer {closo-[Zn2 Sn8 ]}2 moieties bridged by a Zn-Zn bond. Such Zn-Sn cluster not only exhibits a novel example of mixed-valence ZnI /ZnII for stabilizing highly active anion species, but also indicates the [Sn8 ]6- cluster can act as a novel bridging ligand, like arene, with a η4 :η4 -fashion. Theoretical calculations indicate that a significant delocalization of electrons over Zn atoms plays a vital role in the stabilization of the [Sn8 ]6- species. The AdNDP and magnetic response analyses clearly showed the presence of local σ-aromaticity in three cluster fragments: two ZnSn4 caps and Sn8 square antiprism.

3.
Angew Chem Int Ed Engl ; 59(39): 17286-17290, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32608037

RESUMO

In this work, the largest heterometallic supertetrahedral clusters, [Zn6 Ge16 ]4- and [Cd6 Ge16 ]4- , were directly self-assembled through highly-charged [Ge4 ]4- units and transition metal cations, in which 3-center-2-electron σ bonding in Ge2 Zn or Ge2 Cd triangles plays a vital role in the stabilization of the whole structure. The cluster structures have an open framework with a large central cavity of diameter 4.6 Šfor Zn and 5.0 Šfor Cd, respectively. Time-dependent HRESI-MS spectra show that the larger clusters grow from smaller components with a single [Ge4 ]4- and ZnMes2 units. Calculations performed at the DFT level indicate a very large HOMO-LUMO energy gap in [M6 Ge16 ]4- (2.22 eV), suggesting high kinetic stability that may offer opportunities in materials science. These observations offer a new strategy for the assembly of heterometallic clusters with high symmetry.

4.
Med Princ Pract ; 25(3): 260-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26907185

RESUMO

OBJECTIVE: To evaluate menstrual disturbances and sex hormonal status in premenopausal women with end-stage renal disease (ESRD). SUBJECTS AND METHODS: The study consisted of 184 patients with ESRD treated with one of four treatment modalities (46/modality): conventional hemodialysis (CHD), continuous ambulatory peritoneal dialysis (CAPD), nocturnal hemodialysis (NHD) and renal transplantation (RT). Blood samples were collected to determine sex hormone levels. Sociodemographic and clinical data were collected from medical records. A questionnaire was administered to analyze menstrual patterns, and the final analysis included 46, 43, 40 and 36 patients in the CHD, CAPD, NHD and RT groups, respectively. RESULTS: The overall prevalence of menstrual disturbances was 64.2% for all four treatment modalities (RT: 50%; NHD: 55%; CAPD: 72.1%, and CHD: 76.1%). Serum prolactin levels were significantly lower (p < 0.01) in the NHD (25.1 ± 10.9 ng/ml) and RT (13.4 ± 5.1 ng/ml) groups than in the CHD group (55.2 ± 10.8 ng/ml). Serum progesterone levels were significantly higher (p < 0.01) in the NHD (25.7 ± 8.3 nmol/l) and RT (30.1 ± 5.9 nmol/l) groups than in the CHD group (17.7 ± 7.3 nmol/l). Moreover, the hormonal status (follicle-stimulating hormone, luteinizing hormone and testosterone) was much closer to normal in the NHD and RT groups compared to the other two groups. CONCLUSIONS: In this study, successful transplantation and NHD partially improved the symptoms of menstrual disturbances. Therefore, we recommend that further studies are necessary to confirm our finding in ESRD patients.


Assuntos
Falência Renal Crônica/epidemiologia , Falência Renal Crônica/terapia , Distúrbios Menstruais/epidemiologia , Pré-Menopausa/fisiologia , Estudos Transversais , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Transplante de Rim/métodos , Hormônio Luteinizante/sangue , Progesterona/sangue , Prolactina/sangue , Diálise Renal/métodos , Testosterona/sangue
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 593-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27209775

RESUMO

In the near-infrared spectroscopy, the Forward Interval Partial Least Squares (FiPLS) and Backward Interval Partial Least Squares (BiPLS) are commonly used modeling methods, which are based on the wavelength variable selection. These methods are usually of high prediction accuracy, but are strongly characteristic of greedy search, which causes that the intervals selected are not good enough to indicate the analyte information. To solve the problem, a spectral characteristic intervals selection strategy (FB-iPLS) based on the combination of FiPLS and BiPLS is proposed. On the basis of spectral segmentation, both FiPLSs are used to select useful intervals, and BiPLS is used to delete useless intervals, so as to perform the selection and deletion of the characteristic variables alternatively, which conducts a two-way choice of the target characteristic variables, and is used to improve the robustness of the model. The experiments on determining the ethanol concentration in pure water are conducted by modeling with FiPLS, BiPLS and the proposed method. Since different size of intervals will affect the result of the model, the experiments here will also examine the model results with different intervals of these three models. When the spectrum is divided into 60 segments, the FB-iPLS method obtains the best prediction performance. The correlation coefficients (r) of the calibration set and validation set are 0.967 7 and 0.967 0 respectively, and the cross-validation root mean square errors (RMSECV) are 0.088 8 and 0.057 1, respectively. Compared with FiPLS and BiPLS, the overall prediction performance of the proposed model is better. The experiments show that the proposed method can further improve the predictive performance of the model by resolving the greedy search feature against BiPLS and FiPLS, which is more efficient for and representative of the selection of characteristic intervals.

7.
Mol Cell Biochem ; 383(1-2): 137-48, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23867991

RESUMO

Histone deacetylases (HDACs) inhibitor is a promising new approach to the treatment of lung cancer therapy via inhibiting cell growth and inducing apoptosis. miR-15a and miR-16-1 are important tumor suppressors through modulating B cell lymphoma 2 (Bcl-2), Cyclin D1, D2, and others. However, whether HDACs inhibitor modulates the expression of miR-15a/16-1 in lung cancer is still unknown. The purpose of our study was to identify a new miRNA-mediated mechanism which plays an important role in the anti-cancer effects of HDACs inhibitor. We found HDACs inhibitors trichostatin A (TSA) and sodium butyrate upregulated the expression of miR-15a/16-1, residing in the host tumor suppressor Dleu2 gene, through increasing the histone acetylation in the region of Dleu2/miR-15a/16-1 promoter in lung cancer cells. Moreover, among class Ι HDACs subtypes, only knockdown of HDAC3 by specific siRNA increased the hyperacetylation of Dleu2/miR-15a/16-1 promoter region and finally resulted in the upregulation of miR-15a/16-1. Furthermore, overexpression of miR-15a/16-1, which were always deleted or downregulated in lung cancer cells, effectively suppressed cell growth and reduced colony formation. Finally, TSA reduced the expression of Bcl-2, an important survival protein in lung cancer cells, partly through upregulation of miR-15a/16-1. Therefore, this offers a therapeutic strategy that lung cancer patients who exhibit low level of miR-15a/16-1 or high activity of HDACs may benefit from HDACs inhibitor-based therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Ácidos Hidroxâmicos/farmacologia , MicroRNAs/genética , Proteínas Supressoras de Tumor/genética , Acetilação/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Ácido Butírico/farmacologia , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Histonas/metabolismo , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/metabolismo , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Longo não Codificante , Transferases , Ensaio Tumoral de Célula-Tronco , Proteínas Supressoras de Tumor/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
8.
Chem Commun (Camb) ; 58(19): 3190-3193, 2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35171154

RESUMO

We report here a new double-cage endohedral Ge cluster, [Co2@(Ge17Ni)]4-, fused through two [Co@(Ge9Ni)] moieties with a shared Ni-Ge edge. This ternary Co-Ge-Ni species not only represents the first double-cage example of an 18-vertex Zintl cluster, but also fills in the missing link of the edge fusion model in the double-cage systems.

9.
Nat Prod Res ; 36(3): 707-713, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32757631

RESUMO

Series of thioether derivatives containing 4-methylumbelliferone fused oxazole moiety were designed and synthesised, their structures were fully characterized by 1H NMR, 13C NMR and HR-ESI-MS as well. Moreover, the in vitro antifungal potency of the title compounds were preliminarily evaluated for their possible use as a fungicide. Meanwhile, ethyl thioethers 3aa and 3ba displayed remarkable inhibitory effect against the mycelium growth of Valsa mali and Botrytis cinerea with EC50 of 12-16 µg/mL. Furthermore, compounds 3aa and 3ba also exhibited > 88% protective and curative effect against B. cinerea on tomato fruits at 90 µg/mL. Additionally, the environmental toxicity of the title compounds against the brine shrimp Artemia salina were evaluated as well. The results indicated that most of the title compounds exhibited weak toxic to aquatic organism A. salina.


Assuntos
Antifúngicos , Fungicidas Industriais , Antifúngicos/farmacologia , Botrytis , Fungicidas Industriais/farmacologia , Himecromona , Oxazóis/farmacologia , Relação Estrutura-Atividade , Sulfetos/farmacologia
10.
Nat Commun ; 13(1): 2149, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35444180

RESUMO

Understanding the structural changes taking place during the assembly of single atoms leading to the formation of atomic clusters and bulk materials remains challenging. The isolation and theoretical characterization of medium-sized clusters can shed light on the processes that occur during the transition to a solid-state structure. In this work, we synthesize and isolate a continuous 24-atom cluster Ge244-, which is characterized by X-ray diffraction analysis and Energy-dispersive X-ray spectroscopy, showing an elongated structural characteristic. Theoretical analysis reveals that electron delocalization plays a vital role in the formation and stabilization of the prolate cluster. In contrast with carbon atoms, 4 s orbitals of Ge-atoms do not easily hybridize with 4p orbitals and s-type lone-pairs can be localized with high occupancy. Thus, there are not enough electrons to form a stable symmetrical fullerene-like structure such as C24 fullerene. Three aromatic units with two [Ge9] and one [Ge6] species, connected by classical 2c-2e Ge-Ge σ-bonds, are aligned together forming three independent shielding cones and eventually causing a collapse of the global symmetry of the Ge244- cluster.

11.
Chem Commun (Camb) ; 57(6): 797-800, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33355564

RESUMO

Caspase-3/8 are key members of the cysteine-aspartyl protease family with pivotal roles in apoptosis. We have designed and synthesized self-assembling probes, Nap-GFFpYDEVD-AFC and Nap-GFFpYIETD-AFC, with fluorescence 'turn-on' properties for real-time monitoring of Caspase-3/8 activity in living cells.


Assuntos
Caspase 3/análise , Caspase 8/análise , Ensaios Enzimáticos/métodos , Corantes Fluorescentes/química , Nanofibras/química , Caspase 3/metabolismo , Caspase 8/metabolismo , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Microscopia Confocal , Estrutura Molecular , Fatores de Tempo
12.
Front Psychiatry ; 12: 637789, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859582

RESUMO

Background: Schizophrenia is a severe mental disorder, which has a major impact on the quality of life and imposes a huge burden on the family. However, the pathogenesis of schizophrenia remains unclear and there are no specific biomarkers. Therefore, we intend to explore whether cf-DNA levels are related to the occurrence and development of schizophrenia. Methods: We analyzed and compared the concentration of cf-DNA in 174 SZ patients and 100 matched healthy controls by using quantitative real-time PCR by amplifying the Alu repeats. Results: We found that cf-DNA levels in peripheral blood reliably distinguished SZ patients from healthy controls (P < 0.05). The ROC analysis also supports the above conclusion. By tracking the absolute concentration of serum cf-DNA in primary cases, we found a distinct increase before treatment with antipsychotics, which decreased progressively after treatment. Conclusions: The present work indicates that cf-DNA may improve the efficiency of disease diagnosis, and the level of cf-DNA plays a predictive role in the development of schizophrenia. By evaluating the level of cf-DNA, we might play a certain role in a more reasonable and standardized clinical treatment of schizophrenia.

13.
Life Sci ; 241: 117165, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31838136

RESUMO

AIMS: Previous work has reported the closely correlation between inflammation and carcinogenesis, while the role of NALP3, the key component of inflammasome activation in NSCLC remains elusive. This study was to unravel the mechanism of NALP3 on modulating NSCLC cancer cell growth. METHODS: IHC and immuno-blot were performed to analyze expression of NALP3 and indicated molecules. CCK-8 and xenograft nude mice assay were used to evaluate cell growth in vitro and in vivo. Bioenergetics assay was performed to measure OXPHOS and aerobic glycolysis. siRNA and shRNA were constructed to knockdown endogenous NALP3 and DNMT1. Co-immunoprecipitation was applied to confirm the interaction between NALP3 and DMAP1. BioProfile FLEX analyzer and Lactate Reagent Kit were used to measure relative level glucose uptake and lactate production. KEY FINDINGS: We reported NALP3 were up-regulated in NSCLC tumor tissues. NALP3 depletion suppressed cancer cell growth in vitro and in vivo. Moreover, data showed depletion of NALP3 promoted cell bioenergetics switch from aerobic glycolysis to OXPHOS. Additionally, we found NALP3 interacted with DMAP1 and alteration of NALP3 increased DNMT1 level. Subsequently, we clarified depletion of DNMT1 significantly suppressed NSCLC cell growth and orchestrated cellular metabolism which was similar to the effects of NALP3 knockdown. Finally, our data showed high NALP3 was associated with poor outcomes, and correlated with TNM stage and differentiation. SIGNIFICANCE: Current study elucidated NALP3 could promote metabolic reprogramming to regulate NSCLC cell growth and suggested that NALP3 may be considered as a novel biomarker and therapeutic target for NSCLC patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/secundário , Metabolismo Energético , Regulação Neoplásica da Expressão Gênica , Glicólise , Neoplasias Pulmonares/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proliferação de Células , Estudos de Coortes , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Nat Commun ; 11(1): 5286, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33082326

RESUMO

Sandwich-type clusters with the planar fragment containing a heterometallic sheet have remained elusive. In this work, we introduce the [K(2,2,2-crypt)]4{(Ge9)2[η6-Ge(PdPPh3)3]} complex that contains a heterometallic sandwich fragment. The title compound is structurally characterized by means of single-crystal X-ray diffraction, which reveals the presence of an unusual heteroatomic metal planar fragment Ge@Pd3. The planar fragment contains a rare formal zerovalent germanium core and a peculiar bonding mode of sp2-Ge@(PdPPh3)3 trigonal planar structure, whereas the nonagermanide fragments act as capping ligands. The chemical bonding pattern of the planar fragment consists of three 2c-2e Pd-Ge σ-bonds attaching Pd atoms to the core Ge atom, while the binding between the planar fragment and the aromatic Ge9 ligands is provided by six 2c-2e Pd-Ge σ-bonds and two delocalized 4c-2e σ-bonds. The synthesized cluster represents a rare example of a sandwich compound with the heteroatomic metal planar fragment and inorganic aromatic capping ligands.

15.
Zhongguo Yi Liao Qi Xie Za Zhi ; 33(1): 59-61, 2009 Jan.
Artigo em Zh | MEDLINE | ID: mdl-19459354

RESUMO

Introduced the "particles" item testing progress and some notes, using Coulter Multisizer, about medical devices and drugs wrapper, with an expectation of some help for the "particles" item tests in the solution in these area.


Assuntos
Equipamentos e Provisões , Teste de Materiais/instrumentação , Contaminação de Equipamentos/prevenção & controle , Teste de Materiais/métodos , Tamanho da Partícula , Controle de Qualidade
16.
Zhongguo Yi Liao Qi Xie Za Zhi ; 29(4): 283-4, 2005 Jul.
Artigo em Zh | MEDLINE | ID: mdl-16268358

RESUMO

This article describes the opportune time, method and procedures of "P" control chart's establishment during product manufacturing. "P" control chart of statistical data is the most commonly used in data analysis and the quality control system.


Assuntos
Equipamentos e Provisões/normas , Controle de Qualidade
17.
Huan Jing Ke Xue ; 34(5): 2044-50, 2013 May.
Artigo em Zh | MEDLINE | ID: mdl-23914566

RESUMO

Air pollution from freshwater port is mainly caused by dust pollution, including material loading and unloading dust, road dust, and wind erosion dust from stockpile, bare soil. The dust pollution from a single dock characterized in obvious difference with air pollution from multiple scattered docks. Jining Port of Shandong Province was selected as a case study to get superposition impact contribution of air pollution for regional air environment from multiple scattered docks and to provide technical support for system evaluation of port air pollution. The results indicate that (1) the air pollution from freshwater port occupies a low proportion of pollution impact on regional environmental quality because the port is consisted of serveral small scattered docks; (2) however, the geometric center of the region distributed by docks is severely affected with the most superposition of the air pollution; and (3) the ADMS model is helpful to attain an effective and integrated assessment to predict a superposition impact of multiple non-point pollution sources when the differences of high-altitude weather conditions was not considered on a large scale.


Assuntos
Poluição do Ar/análise , Poeira/análise , Monitoramento Ambiental/métodos , China , Previsões , Água Doce , Modelos Teóricos , Rios , Análise Espacial
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