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2.
Plant Biol (Stuttg) ; 19(5): 760-766, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28509436

RESUMO

Studies have indicated that florivory and nectar robbing may reduce reproductive success of host plants. However, whether and how these effects might interact when plants are simultaneously attacked by both florivores and nectar robbers still needs further investigation. We used Iris bulleyana to detect the interactions among florivory, nectar robbing and pollination, and moreover, their effects on plant reproductive success. Field investigations and hand-pollination treatments were conducted on two experimental plots from a natural population, in which Experimental plot was protected from florivores and Control plot was not manipulated. The flower calyx was bitten by sawflies to consume the nectary, and three bumblebee species were pollinators. In addition, the short-tongued pollinator, Bombus friseanus, was the only robber when there was a hole made by a sawfly. The bumblebee had significantly shortened flower handling time when robbing, as compared to legitimate visits. Pollinator visitation and seed production decreased significantly in damaged flowers. However, seed production per flower after supplementary hand-pollination did not differ significantly between damaged and undamaged flowers. Compared to the Experimental plot, bumblebees visited fewer flowers per plant in a foraging bout in the Control plot. The flowers damaged by florivory allowed B. friseanus to shift to a nectar robber. Florivory and nectar robbing collectively decreased plant reproductive success by consuming nectar resources, which may reduce attractiveness to pollinators of the damaged flowers. However, the changes in pollinator behaviour might be beneficial to the plant by reducing the risk of geitonogamous mating.


Assuntos
Iridaceae/fisiologia , Néctar de Plantas/fisiologia , Polinização/fisiologia , Reprodução/fisiologia , Animais , Abelhas/fisiologia
3.
Cell Death Dis ; 6: e1604, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25611379

RESUMO

Osteosarcoma is the most common primary malignant tumor of bone, the long-term survival of which has stagnated in the past several decades. Celastrol, a triterpene from traditional Chinese medicine, has been proved to possess potent anti-tumor effect on various cancers. However, the effect of celastrol on human osteosarcoma and the underlying mechanisms remains to be elucidated. We reported here that celastrol could inhibit cell proliferation by causing G2/M phase arrest. Exposure to celastrol resulted in the activation of caspase-3, -8, and -9, indicating that celastrol induced apoptosis through both extrinsic and intrinsic pathways. Autophagy occurred in celastrol-treated cells as evidenced by formation of autophagosome and accumulation of LC3B-II. The celastrol-induced cell death was remarkably restored by the combination of autophagy and apoptosis inhibitors. Furthermore, inhibition of apoptosis enhanced autophagy while suppression of autophagy diminished apoptosis. Celastrol also induced JNK activation and ROS generation. The JNK inhibitor significantly attenuated celastrol-triggered apoptosis and autophagy while ROS scavenger could completely reverse them. The ROS scavenger also prevented G2/M phase arrest and phosphorylation of JNK. Importantly, we found that celastrol had the similar effects on primary osteosarcoma cells. Finally, in vivo, celastrol suppressed tumor growth in the mouse xenograft model. Taken together, our results revealed that celastrol caused G2/M phase arrest, induced apoptosis and autophagy via the ROS/JNK signaling pathway in human osteosarcoma cells. Celastrol is therefore a promising candidate for development of antitumor drugs targeting osteosarcoma.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Osteossarcoma/enzimologia , Osteossarcoma/patologia , Espécies Reativas de Oxigênio/metabolismo , Triterpenos/farmacologia , Animais , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Biológicos , Osteossarcoma/ultraestrutura , Triterpenos Pentacíclicos , Fagossomos/efeitos dos fármacos , Fagossomos/metabolismo , Fagossomos/ultraestrutura , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Zhonghua Jie He He Hu Xi Za Zhi ; 14(1): 22-4, 62, 1991 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-1879006

RESUMO

The drug monitoring of serum concentration of Aminophylline by means of HPLC and FPIA to 72 patients suffering from bronchial asthma and asthmatic bronchitis; the relations among the quantities, serum drug concentrations, effects and side-effects of Aminophylline were reported. The results showed that it is necessary to take Aminophylline individually under the guide of drug monitoring. The monitoring should be combined with clinical observation and comprehensive treatment of the diseases. The major values of effective serum concentration of Aminophylline range from 8 to 20 mg/L, while above the value of 20 mg/L, its side-effects will significantly increase. It is safe and effective for asthmatic adult patients (over 55 Kg weight) if the oral dose of Aminophylline is not more than 200 mg Q8h, or for others with continuous asthmatic attacks to be given with 250 mg of Aminophylline intravenously in drip followed by oral dose of the drug 200 mg Bid.


Assuntos
Aminofilina/sangue , Asma/tratamento farmacológico , Bronquite/tratamento farmacológico , Adulto , Idoso , Aminofilina/administração & dosagem , Asma/sangue , Bronquite/sangue , Cromatografia Líquida de Alta Pressão , Feminino , Imunoensaio de Fluorescência por Polarização , Humanos , Masculino , Pessoa de Meia-Idade
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