Cholecystokinin octapeptide antagonizes apoptosis in human retinal pigment epithelial cells

Although cholecystokinin octapeptide-8 is important for neurological function, its neuroprotective properties remain unclear. We speculated that cholecystokinin octapeptide-8 can protect human retinal pigment epithelial cells against oxidative injury. In this study, retinal pigment epithelial cells were treated with peroxynitrite to induce oxidative stress. Peroxynitrite triggered apoptosis in these cells, and increased the expression of Fas-associated death domain, Bax, caspase-8 and Bcl-2. These changes were suppressed by treatment with cholecystokinin octapeptide-8. These results suggest that cholecystokinin octapeptide-8 can protect human retinal pigment epithelial cells against apoptosis induced by peroxynitrite.

Puerarin antagonizes peroxyntrite-induced injury in retinal pigment epithelial cells

A rat model of diabetes mellitus was established by intraperitoneal injection of streptozotocin. Three days later, the rats were intraperitoneally administered 140 mg puerarin/kg daily, for a total of 60 successive days. DNA ladder results showed increased apoptosis over time in retinal pigment epithelial cells from rats with streptozotocin-induced diabetes mellitus. Western blot analysis, Reverse transcription-PCR, immunohistochemistry, and flow cytometry results showed increased expression of 3-nitrotyrosine, a peroxyntrite marker, as well as inducible nitric synthase and Fas/FasL, in retinal pigment epithelial cells. Puerarin reversed these changes, and results demonstrated that puerarin inhibited Fas/FasL expression and alleviated peroxyntrite injury to retinal pigment epithelial cells. These results suggested that puerarin inhibited production of inducible nitric oxide synthase and directly antagonized peroxyntrite injury in retinal pigment epithelial cells.

Apoptosis-linked antifungal effect of ambroxol hydrochloride by cystolic calcium concentration disturbance in resistant Candida albicans

Dear Editor,Since the early 1980s,the incidence of fungal infections has significantly increased in immunocompromised individuals(WisplinghofF et al.,2004;Pfaller and Diekema,2007).However,due to the extensive and indiscriminate use of available antifungal agents,an increasing number of antifungal-resistant pathogens have been isolated over the past few decades(Sanglard and Odds,2002).C.albicans,an important opportunistic fxingal pathogen,is becoming increasingly resistant to several antifungal agents,particularly triazole compounds.Drug resistance in C.albicans has emerged as an important public health concern(Sanglard and Odds,2002).Although ambroxol hydrochloride(ABH)has recently been found to display antifungal activity against susceptible C.albicans,its antifungal effect and mechanism against resistant C.albicans have not yet been thoroughly investigated.The aim of this study was to elucidate the antifungal effects(in vitro and in vivo)and mechanisms of ABH against resistant C.albicans.

Cropping pattern optimization considering uncertainty of water availability and water saving potential

In arid and semi-arid areas,the profitability of irrigated agriculture mainly depends on the availability of water resources and optimal cropping patterns of irrigation districts.In this study,an integrated agricultural cropping pattern optimization model was developed with considering the uncertainty of water availability and water saving potential in the future,aiming to maximize agricultural net benefit per unit of irrigation water.The available water which was based on the uncertainty of runoff was divided into five scenarios.The irrigation water-saving potential in the future was quantified by assuming an increase in the rate irrigation water-saving of 10% and 20%.The model was applied to the middle reaches of Heihe River basin,in Gansu Province,China.Results showed that if the irrigation water-saving rate was assumed to increase by 10%,then the net water-saving quantity would increase by 21.5-22.5 million m3 and the gross water-saving quantity would increase by 275.7-303.0 million m3.Similarly,if the irrigation water-saving rate increased by 20%,then the net water-saving quantity would increase by 43.0-45.1 million m3 and the gross water-saving quantity would increase by 331.7-383.2 million m3.If the agricultural cropping pattern was optimized,the optimal water and cultivated area allocation for maize would be greater than those for other crops.Under the premise that similar volume of irrigation water quantity was available in different scenarios,results showed differences in system benefit and net benefit per unit of irrigation water,for the distribution of available irrigation water was diverse in different irrigation districts.

Modelling and analysis of hybrid stochastic timed Petri net

In this paper,an interesting Hybrid Stochastic Timed Petri Net(HSTPN)is proposed for a class of hybrid systems.The proposed HSTPN can be adopted to represent hybrid systems with discrete,continuous,conflicting,time-delay and stochastic characteristics simultaneously.The proposed HSTPN outperforms conventional hybrid Petri net models in terms of describing the scalability and immediacy of hybrid systems.Advantages of the HSTPN on describing hybrid system are verified by establishing some equivalent models of HPN and its derived models.