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1.
PLoS One ; 18(12): e0295755, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38091322

RESUMO

Safety management is a key issue in the railroad industry that needs to be continuously focused on. And it is essential to study causes of accidents for preventing accidents. However, there is a limited academic discussion on the systematic study of organizations and accidents, as well as their safety-related interactions and accidents, as opposed to human-caused disasters. Thus, the model of China's railway safety supervision and management system by sorting out the existing organizations involved in management in China is established in this paper. Firstly, social forces and auxiliary enterprises are specifically added to the model. And then, the relationship between organizations and accidents, as well as the relationship between safety interactions among organizations and accidents are explored by analyzing 224 accident reports, which led to 4 principles for accident prevention. Finally, based on these principles, measures to secure organizational nodes, as well as measures to promote safe interactions among organizations are proposed. The results showed that: (1) China Railway node is not only the most critical node in the safety supervision and management system but also the most vulnerable to the influence of other nodes. (2) The accident occurred due to the simultaneous occurrence of an accident at the China Railway node and the social force node. (3) When there are often safety risks in auxiliary enterprises and social forces simultaneously, the government's management is likely to be defective. The findings in this study can provide helpful references not only for improvement of safety management system structure and supervision and management mechanism but also for the formulation of safety supervision and management policies in China and other countries.


Assuntos
Prevenção de Acidentes , Gestão da Segurança , Humanos , Gestão da Segurança/métodos , Prevenção de Acidentes/métodos , Acidentes , China , Organizações
2.
Small ; 19(39): e2302811, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37194977

RESUMO

Polymerized ionic liquids (PILs) with super ion diffusion kinetics have aroused considerable attention in rechargeable batteries, which are very promising to solve the problem of the slow ion diffusion kinetics in organic electrode materials. Theoretically, PILs incorporated redox groups are very suitable as anode materials to realize "superlithiation" performance, achieving high lithium storage capacity. In this study, redox pyridinium-based PILs (PILs-Py-400) have been synthesized through trimerization reactions by pyridinium ionic liquids with cyano groups under an appropriate temperature (400 °C). The positively charged skeleton, extended conjugated system, abundant micropores, and amorphous structure for PILs-Py-400 can boost the utilization efficiency of redox sites. A high capacity of 1643 mAh g-1 at 0.1 A g-1 (96.7% of the theoretical capacity) has been obtained, indicating intriguing 13 Li+ redox reactions in per repeating unit of one pyridinium ring, one triazine ring, and one methylene. Moreover, PILs-Py-400 exhibit excellent cycling stability with a capacity of around 1100 mAh g-1 at 1.0 A g-1 after 500 cycles, and the capacity retention is 92.2%.

3.
Biochem Genet ; 60(5): 1676-1694, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35079913

RESUMO

microRNA-200c-3p (miR-200c-3p) has emerged as an important tumor growth regulator. However, its function in papillary thyroid carcinoma (PTC) is poorly understood. This study was conducted to investigate the role of miR-200c-3p in the progression of human PTC. The miR-200c-3p expression in human PTC tissues and cell lines was evaluated. The target relationship between miR-200c-3p and candidate genes was predicted through bioinformatic analysis and confirmed with a luciferase reporter assay. miRNA or gene expression was altered using transfection, and cell behavior was analyzed using CCK-8, wound healing, Transwell, and colony formation assays. The tumor-promoting effects of miR-200c-3p were evaluated by xenografting tumors with K1 cells in nude mice. The expression level of miR-200c-3p in human PTC tissues and cell lines markedly increased, and this increased expression was significantly associated with a worse overall survival. When inactivated, miR-200c-3p suppressed K1 cells' malignant behaviors, including decreasing proliferation and attenuating colony formation, migration, and invasion. Its inactivation also attenuated the development of xenografted K1 cells in nude mice. The effects of miR-200c-3p mimics on promoting the malignant behaviors of PTC cells were remarkably reversed by the overexpression of ATP2A2, as a downstream target of miR-200c-3p. miR-200c-3p acts as an oncogenic gene and promotes the malignant biological behaviors of human PTC cells, thereby directly targeting ATP2A2. This regulated axis may be used as a potential therapy of PTC.


Assuntos
MicroRNAs , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , MicroRNAs/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia
4.
Bioorg Med Chem Lett ; 30(17): 127369, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32738991

RESUMO

Based on the characteristic of benzo[d][1,2,3]thiadiazole to induce the systemic acquired resistance and improve the immunity of plants, benzo[d][1,2,3]thiadiazole was introduced into 1,2,3-benzotriazin-4-one, thirty-one novel 1,2,3-benzotriazin-4-one derivatives containing benzo[d][1,2,3]thiadiazole were designed and synthesized. Nematicidal activity showed that most of the synthesized compounds exhibited great inhibitory activity in vivo against Meloidogyne incognita at 20 mg/L. Among 31 tested compounds, A2 and A3 showed an excellent nematicidal activity with the inhibition rate of 50.4% and 53.1% at the concentration of 1.0 mg/L, respectively. The influence of substituent type and position was investigated. The relationship between structure and activity was also preliminary analyzed.


Assuntos
Antinematódeos/síntese química , Tiadiazóis/química , Triazinas/química , Animais , Antinematódeos/química , Antinematódeos/farmacologia , Desenho de Fármacos , Raízes de Plantas/parasitologia , Plantas/parasitologia , Relação Estrutura-Atividade , Triazinas/síntese química , Triazinas/farmacologia , Tylenchoidea/efeitos dos fármacos
5.
J Agric Food Chem ; 63(31): 6883-9, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26145729

RESUMO

A series of novel 1,2,3-benzotriazin-4-one derivatives were synthesized by the reaction of 3-bromoalkyl-1,2,3-benzotriazin-4-ones with potassium salt of 2-cyanoimino-4-oxothiazolidine in the presence of potassium iodide. Nematicidal assays in vivo showed that some of them exhibited good control efficacy against the cucumber root-knot nematode disease caused by Meloidogyne incognita, up to 100% at the concentration of 10.0 mg L(-1), which indicated that 1,2,3-benzotriazin-4-one derivatives might be potential for novel promising nematicides. The nematicidal activity was influenced by the combination of substituent type, substituted position, and linker length in the molecule. The inhibition rate data at the concentrations of 5.0 and 1.0 mg L(-1) for the compounds with high inhibitory activities were also provided. When tested in vitro, none of them showed direct inhibition against M. incognita. The investigation of a significant difference between in vivo and in vitro data is in progress.


Assuntos
Antinematódeos/toxicidade , Triazinas/toxicidade , Tylenchoidea/efeitos dos fármacos , Animais , Antinematódeos/síntese química , Antinematódeos/química , Cucumis sativus/parasitologia , Estrutura Molecular , Doenças das Plantas/parasitologia , Triazinas/síntese química , Triazinas/química , Tylenchoidea/fisiologia
6.
Biosens Bioelectron ; 26(6): 3044-9, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21195601

RESUMO

A novel electrochemical immunosensor for sensitive detection of cancer biomarker prostate specific antigen (PSA) based on nitrodopamine (NDA) functionalized iron oxide nanoparticles (NDA-Fe(3)O(4)) is described. NDA-Fe(3)O(4) was used both for the immobilization of primary anti-PSA antibody (Ab(1)) and as secondary anti-PSA antibody (Ab(2)) label. For the preparation of the label, mediator thionine (TH) was first conjugated onto NDA-Fe(3)O(4) based on the amino groups of NDA, and then the amino group of TH was used to immobilize horseradish peroxidase (HRP) and Ab(2). Due to the high amount of NDA anchored onto Fe(3)O(4) surface, the loading of antibodies as well as mediator and enzyme onto NDA-Fe(3)O(4) was substantially increased, which increased the sensitivity of the immunosensor. The resulting immunosensor displayed a wide range of linear response (0.005-50 ng/mL), low detection limit (4 pg/mL), good reproducibility and stability. The immunosensor was used to detect the PSA contents in serum samples with satisfactory results.


Assuntos
Técnicas Biossensoriais/métodos , Nanopartículas de Magnetita , Antígeno Prostático Específico/sangue , Anticorpos Imobilizados , Técnicas Biossensoriais/estatística & dados numéricos , Análise Química do Sangue/métodos , Análise Química do Sangue/estatística & dados numéricos , Dopamina/análogos & derivados , Técnicas Eletroquímicas , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão , Microtecnologia , Nanotecnologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico
7.
Biosens Bioelectron ; 26(2): 627-31, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20708918

RESUMO

In this work, we developed a novel kind of label based on dumbbell-like Au-Fe3O4 nanoparticles (NPs) for the preparation of electrochemical immunosensor for the detection of cancer biomarker prostate specific antigen (PSA). The signal amplification strategy, using the synergetic effect present in Au-Fe3O4 to increase the reduction ability of the NPs toward H2O2, improves the sensitivity and detection limit of the immunosensor. With primary anti-PSA antibody (Ab1) immobilized onto graphene surface and secondary anti-PSA antibody (Ab2) adsorbed onto the Au of the Au-Fe3O4 NPs, the immunosensor prepared through a sandwich structure displays a wide linear range (0.01-10 ng/mL), low detection limit (5 pg/mL), good reproducibility and stability. These labels for immunosensors may provide many potential applications for the detection of different biomolecules.


Assuntos
Técnicas Biossensoriais/instrumentação , Condutometria/instrumentação , Ouro/química , Peróxido de Hidrogênio/química , Imunoensaio/instrumentação , Nanopartículas de Magnetita/química , Antígeno Prostático Específico/sangue , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Nanopartículas de Magnetita/ultraestrutura , Masculino , Tamanho da Partícula , Coloração e Rotulagem/métodos
8.
Biomaterials ; 31(28): 7332-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20619889

RESUMO

A class of immuno-labels based on poly(ethylene glycol)-poly(lactic acid) (PEG-PLA) polymeric vesicles was developed in this study. To fabricate these immune-labels, the uniform Fe(3)O(4) nanoparticles (NPs) were loaded into the vesicles followed by conjugating secondary antibody (Ab(2)) onto the vesicles surface, named Ab(2)-PEG-PLA-Fe(3)O(4). The resulting Ab(2)-PEG-PLA-Fe(3)O(4) demonstrated high catalytic activity towards H(2)O(2), and the sensitivity of the sandwich-type immunosensor using this label for prostate specific antigen (PSA) detection increased greatly. The immunosensor based on this label exhibited high sensitivity, wide linear range (0.005-10 ng/mL), low detection limit (2 pg/mL), good reproducibility, selectivity and stability. These labels for immunosensors may provide many potential applications for the ultrasensitive detection of different cancer biomarkers. In addition, this technique also has the potential to be extended to the loading of other interesting material for preparing various kinds of labels to meet the different requirements in immunoassays.


Assuntos
Técnicas Biossensoriais , Compostos Férricos/química , Ácido Láctico/química , Nanopartículas/química , Polietilenoglicóis/química , Polímeros/química , Animais , Anticorpos/química , Anticorpos/metabolismo , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Portadores de Fármacos/química , Humanos , Teste de Materiais , Estrutura Molecular , Tamanho da Partícula , Poliésteres
9.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): o2216, 2010 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-21588587

RESUMO

In the title compound, C(8)H(15)N(3)O(4), the 2-(nitro-methyl-ene)imidazolidine fragment is close to being planar (r.m.s. deviation = 0.027 Å), which may be correlated with delocalization of the electrons and the effect of the strongly electron-withdrawing NO(2) group. An intra-molecular N-H⋯O link generates an S(6) ring. The same H atom also forms a weak inter-molecular N-H⋯O hydrogen bond, which results in C(7) chains propagating in [010].

10.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): o2330, 2010 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-21588676

RESUMO

In the title compound, C(11)H(18)N(4)O(2)S(2), the dithiol-ane ring displays an envelope conformation, the tetra-hydro-pyrimidine ring has a conformation that is between half-chair and screw-boat, and the imidazole ring is essentially planar (r.m.s. deviation = 0.0017 Å). No significant directional inter-molecular inter-actions are present in the structure.

11.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): o2359, 2010 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-21588701

RESUMO

In the title compound, C(9)H(15)N(3)O(4), the 1,3-dioxane ring displays a chair conformation and the five-membered ring is close to planar (r.m.s. deviation = 0.054 Å). An intra-molecular N-H⋯O hydrogen bond to one of the nitro-group O atoms generates an S(6) ring. In the crystal, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into C(6) chains propagating in [010] and a C-H⋯O link also occurs.

12.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): o2416, 2010 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-21588742

RESUMO

In the title compound, C(13)H(22)N(4)O(2)S(2), the six-membered ring displays a half-chair conformation. The olefin amine unit is close to being coplanar with the imidazolidine ring (r.m.s. deviation = 0.059 Å). The dithiol-ane ring adopts a twisted conformation. In the crystal, mol-ecules are linked by weak C-H⋯O inter-actions.

13.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): o2451, 2010 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-21588772

RESUMO

In the title compound, C(11)H(19)N(3)O(5), the six-membered ring displays a half-chair conformation and the imidazolidine ring is essentially planar (r.m.s. deviation = 0.088 Å). An inter-molecular hydrogen bond between the hy-droxy O atom and a nitro O atom stabilizes the crystal packing.

14.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): o2759, 2010 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-21588962

RESUMO

In the title compound, C(6)H(11)N(3)O(3), the imidazolidine NH group is involved in a three-center N-H⋯O hydrogen bond, with intra-molecular and inter-molecular branches, to the nitro group O atoms. The centrosymmetric dimers that are formed are further connected by O-H⋯O hydrogen bonds between the hy-droxy and nitro groups into a two-dimensional polymeric structure extending parallel to (101).

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