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1.
Ying Yong Sheng Tai Xue Bao ; 34(1): 123-130, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36799385

RESUMO

We used open-top chambers (OTCs) to simulate the conditions of elevated atmospheric CO2 concentration at the Changwu State Key Agro-Ecological Experimental Station of the Loess Plateau. There were three treatments, CK (maize grown under field conditions with natural atmospheric CO2 concentration), OTC (maize grown in the open-top chamber under natural atmospheric CO2 concentration), and OTCe (maize grown in the open-top chamber under elevated atmospheric CO2 concentration of 700 µmol·mol-1).We explored the responses of non-structural carbohydrate (NSC) and grain quality (soluble sugar, starch and crude protein) of spring maize to elevated CO2 at different growth stages, aiming to provide scientific basis for revealing the adaptation mechanism of maize to elevated CO2. The results showed that the effects of elevated CO2 on NSC content and accumulation in maize varied across organs and growth periods. Elevated CO2 promoted the activation and redistribution of NSC in leaves, stems and roots during reproductive growth period, and significantly increased the amount of NSC conversion to the grains (ATMNSC), as well as the conversion rate to the grains (ARNSC) and the contribution to the grains (ACNSC) in leaves, stems and roots. Compared with CK, the warming effect of OTC inhibited the activation and redistribution of NSC in stems and roots, but promoted the activation and redistribution of NSC in leaves, significantly increased the ATMNSC, ARNSC, and ACNSC of maize leaves. Elevated CO2 did not affect the contents of soluble sugar, starch, and crude protein in maize grains.


Assuntos
Dióxido de Carbono , Zea mays , Dióxido de Carbono/metabolismo , Carboidratos , Grão Comestível/metabolismo , Folhas de Planta/metabolismo , Amido , Açúcares
2.
Reprod Biol Endocrinol ; 18(1): 16, 2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32113479

RESUMO

BACKGROUND: To investigate the effectiveness of the GnRH-a ultra-long protocol, GnRH-a long protocol, and GnRH-a short protocol used in in vitro fertilization-embryo transfer (IVF-ET) in infertile women with endometriosis. METHODS: We searched PubMed, Embase, Web of Science, Cochrane Library, Elsevier Science Direct, OA Library, Google Scholar, China National Knowledge Infrastructure (CNKI), Wanfang Data Knowledge Service Platform, China Science and Technology Journal database, and the China Biology Medicine disc for randomized controlled trials (RCTs) and observational studies (non-RCTs) to evaluate the efficacy of the GnRH-a ultra-long protocol, GnRH-a long protocol, and GnRH-a short protocol in IVF-ET in infertile patients with endometriosis. RESULTS: A total of 21 studies in compliance with the standard literature were included, and RCT and non-RCT studies were analyzed separately. This meta-analysis showed that the GnRH-a ultra-long protocol could improve the clinical pregnancy rate of infertile patients in RCT studies, especially in patients with stages III-IV endometriosis (RR = 2.04, 95% CI: 1.37~3.04, P < 0.05). However, subgroup analysis found the different down-regulation protocols provided no significant difference in improving clinical outcomes in patients with endometriosis in the non-RCT studies. CONCLUSION: This study suggests that the GnRH-a ultra-long protocol can improve the clinical pregnancy rate of the patients with stages III-IV endometriosis in RCT studies. Although it is generally believed that the results of RCT are more reliable, the conclusions of the non-RCT studies cannot be easily neglect, which let us draw conclusions more cautious.


Assuntos
Transferência Embrionária/métodos , Endometriose/fisiopatologia , Fertilização in vitro/métodos , Infertilidade Feminina/fisiopatologia , Indução da Ovulação/métodos , Regulação para Baixo , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/metabolismo , Humanos , Gravidez , Taxa de Gravidez
3.
Yao Xue Xue Bao ; 50(8): 1008-12, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26669001

RESUMO

To discover novel antitumor rhodanine unsaturated ketones, a series of fluoroquinolone (rhodanine α, ß-unsaturated ketone) amine derivatives (5a-5r) were designed and synthesized with fluoroquinolone amide scaffold as a carrier. The structures of eighteen title compounds were characterized by elemental analysis, 1H NMR and MS. The in vitro anti-proliferative activity against Hep-3B, Capan-1 and HL60 cells was evaluated by MTT assay. The results showed that the title compounds not only had more significant anti-proliferative activity against three tested cancer cell lines than that of the parent ciprofloxacin 1, but also exhibited the highest activity against Capan-1 cells. The SAR revealed that some compounds carrying aromatic heterocyclic rings or phenyl attached to an electron-withdrawing carboxyl or sulfonamide substituent were comparable to or better than comparison doxorubicin against Capan-1 cells. As such, it suggests that fluoroquinolone (rhodanine α, ß-unsaturated ketone) amines are promising leads for the development of novel antitumor fluoroquinolones or rhodanine analogues.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Fluoroquinolonas/síntese química , Fluoroquinolonas/farmacologia , Amidas/síntese química , Amidas/farmacologia , Linhagem Celular Tumoral , Células HL-60 , Humanos , Cetonas/síntese química , Cetonas/farmacologia , Rodanina/síntese química , Rodanina/farmacologia
4.
Yao Xue Xue Bao ; 50(5): 569-73, 2015 May.
Artigo em Chinês | MEDLINE | ID: mdl-26234138

RESUMO

To discover novel antitumor fluoroquinolone lead compounds from a rational modification for antibacterial fluoroquinolones, a fused heterocyclic ketone corresponding to thiazolo[2,3- b][1,2,4]triazolone used as a bioisosteric replacement of the C-3 carboxylic acid group of ciprofloxacin 1, and further modification by a Claisen condensation reaction with substituted benzaldehydes formed novel fluoroquinolone C-3 fuse heterocyclic α, ß-unsaturated ketones as the title compounds (6a-6r), separately. The structures of eighteen title compounds were characterized by elemental analysis, 1H NMR and MS, and the in vitro anti-proliferative activity against human hepatoma Hep-3B cells, pancreatic Capan-1 cells and leukemia HL60 cells was evaluated by a MTT assay. The preliminary results showed that the title compounds not only had more significant anti-proliferative activity against three tested cancer cell lines than that of the parent ciprofloxacin 1, but also exhibited the highest activity against Capan-1 cells. In particular, compounds carrying an electron-withdrawing carboxyl (6k, 6m) or sulfonamide substituent (6q, 6r) attached to benzene ring were comparable to or better than constractive drug doxorubicin against Capan-1 cells. As such, it suggests that it is favorable for a fused heterocyclic α, ß-unsaturated ketone scaffold instead of the C-3 carboxylic acid group to improve the antitumor activity of fluoroquinolones.


Assuntos
Antineoplásicos/farmacologia , Ciprofloxacina/análogos & derivados , Fluoroquinolonas/farmacologia , Cetonas/farmacologia , Antibacterianos , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Fluoroquinolonas/síntese química , Células HL-60 , Humanos , Relação Estrutura-Atividade
5.
Yao Xue Xue Bao ; 50(10): 1258-62, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26837171

RESUMO

To discover an efficient strategy for the conversion of the antibacterial activity of fluoroquinolones into the antitumor activity, the three series of C-3 s-triazole-based derivatives including sulfide ketones (6a-6g), thiosemicarbazones (7a-7g) and fused heterocyclic thiazolotriazoles (8a-8g) were synthesized from ciprofloxacin (1), respectively. The structures were characterized by elemental analysis and spectral data. The antitumor activity was tested against three tumor cell lines (Hep-3B, Capan-1 and HL60) using the MTT assay. The three types of compounds all exhibited stronger anti-proliferative activities than ciprofloxacin in the test. The order of their activities was in compounds 7>8>6, and the order of selectivity against cancer cell lines was Capan-1, Hep-3B and HL60. Meanwhile, the SAR revealed that some compounds with electron-drawing group substituted such as fluoro- and nitro-phenyl compounds (6f, 7f, 8f) and (6g, 7g, 8g) displayed more significant activity than the control compounds, especially the IC50 values of thiosemicarbazone compounds 7f and 7g against Capan-1 was comparable to doxorubicin. Thus, a five-membered triazole as the C-3 bioisostere modified with the functionalized side-chain of sulfide-ketone thiosemicarbazone warrants special attention and further investigation.


Assuntos
Antineoplásicos/farmacologia , Ciprofloxacina/química , Cetonas/farmacologia , Triazóis/farmacologia , Antibacterianos/química , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Células HL-60 , Humanos , Sulfetos/farmacologia
6.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 2): m261, 2011 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-21522912

RESUMO

In the title complex, [ZnBr(2)(C(13)H(19)N(3)O)], the Zn(II) atom is five-coordinated by the three N-donor atoms of the Schiff base ligand and by two Br atoms in a distorted square-pyramidal geometry. The morpholine ring adopts a chair conformation.

7.
Eur J Med Chem ; 45(7): 3196-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20362357

RESUMO

In order to explore novel urease inhibitors, three new mononuclear complexes of Cu(II) and Zn(II) with Schiff base 2-{[2-(2-hydroxyethylamino)ethylimino]methyl}-4-nitrophenol have been prepared and structurally characterized by X-ray crystallography. Among the three complexes, two Cu(II) complexes show strong urease inhibitory activities with the IC(50) values being much lower than that of the acetohydroxamic acid, while the Zn(II) complex shows no activity at the concentration of 100 microM.


Assuntos
Cobre/química , Nitrofenóis/química , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Urease/antagonistas & inibidores , Zinco/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Fabaceae/enzimologia , Compostos Organometálicos/síntese química
8.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 10): o2636, 2010 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-21587608

RESUMO

The title compound, C(15)H(16)N(4)O, was prepared by the reaction of pyridine-3-carbaldehyde with 4-dimethyl-amino-benzo-hydrazide in methanol. The dihedral angle between the pyridine and the benzene rings is 5.1 (3)°. In the crystal structure, the hydrazone mol-ecules are linked through inter-molecular N-H⋯O hydrogen bonds, forming chains along the b axis.

9.
Space Med Med Eng (Beijing) ; 15(4): 246-9, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12422858

RESUMO

Objective. To design a portable cardiac monitor system based on the available ordinary ECG machine and works on the basis of QRS parameters. Method. The 80196 single chip microcomputer was used as the central microprocessor and real time electrocardiac signal was collected and analyzed [correction of analysized] in the system. Result. Apart from the performance of an ordinary monitor, this machine possesses also the following functions: arrhythmia analysis, HRV analysis, alarm, freeze, and record of automatic papering. Convenient in carrying, the system is powered by AC or DC sources. Stability, low power and low cost are emphasized in the hardware design; and modularization method is applied in software design. Conclusion. Popular in usage and low cost made the portable monitor system suitable for use under simple conditions.


Assuntos
Arritmias Cardíacas/diagnóstico , Eletrocardiografia Ambulatorial/instrumentação , Microcomputadores , Desenho de Equipamento , Frequência Cardíaca/fisiologia , Humanos , Software
10.
Zhongguo Yi Liao Qi Xie Za Zhi ; 26(4): 241-4, 258, 2002 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16104273

RESUMO

The paper deals with a portable analyzing monitor system with liquid crystal display (LCD), which is low in power consumption and suitable for China's specific conditions. Apart from the development of the overall scheme of the system, the paper introduces the design of the hardware and the software. The 80196 single chip microcomputer is used as the central microprocessor to process and real-time electrocardiac signal data. The system have the following functions: five types of arrhythmia analysis, alarm, freeze, and record of automatic paperfeeding. The portable system can be operated by alternate-current (AC) or direct-current (DC). Its hardware circuit is simplified and its software structure is optimized. Multiple low power consumption and LCD unit are adopted in its modular designs.


Assuntos
Eletrocardiografia Ambulatorial/instrumentação , Microcomputadores , Arritmias Cardíacas/diagnóstico , Computadores , Desenho de Equipamento , Humanos , Software
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