Heterologous expression and characterization of two delta glutathione S-transferases genes involved in imidacloprid metabolism in Grapholita molesta.

Glutathione S-transferases (GSTs) are multifunctional enzymes, and insect GSTs play a pivotal role in the metabolism of insecticides. Grapholita molesta is a worldwide pest that causes substantial economic losses to the fruit industry. However, it remains unclear how imidacloprid, a commonly used insecticide in orchards, is metabolized by G. molesta. In the present study, the synergist diethyl maleate (DEM), which inhibits the GST activity, exhibited a 22-fold synergistic ratio against imidacloprid. Two new GST genes, GmGSTD2 (OR096251) and GmGSTD3 (OR096252), were identified and successfully cloned, showing the highest expression in the Malpighian tubes. Knockdown of GmGSTD2 and GmGSTD3 by RNA interference, increased the mortality of G. molesta from 28% to 47% following imidacloprid treatment. Both recombinant GmGSTD2 and GmGSTD3 proteins exhibited 1-chloro-2,4-dinitrobenzene (CDNB) activity and could be inhibited by imidacloprid in vitro, with maximum inhibition was 60% for GmGSTD2 and 80% for GmGSTD3. These results suggested that GSTs participate in the metabolism of imidacloprid with GmGSTD2 and GmGSTD3 playing key roles in this process.

A New Distance Stereotest by Autostereoscopic Display Using an Eye-Tracking Method.

Objectives: This research aimed to present a novel glasses-free distance random-dot stereotest system (GFDRDSS) using an eye-tracking method. Methods: A single-view autostereoscopic display applying a backlight control system combined with an eye-tracking method and the corresponding random-dot stereotest software were developed to create a GFDRDSS with a viewing distance of 5 m. The stereoacuity of 12 subjects with normal eye position was evaluated using the Randot Stereotest, Stereoscopic Test Charts vol. 3 (Yan's Charts), Distance Randot® Stereotest, and GFDRDSS. Results: The GFDRDSS could provide distinct and stable glasses-free stereoscopic perception even while the subject was moving their head. It could evaluate binocular disparities of 40-2,400 arcsec. Eleven subjects with normal near visual acuity had fine near stereovision (20-60 arcsec) using the Randot stereotest and Yan's Charts. Under refractive correction, 10 subjects had fine stereovision (≤60 arcsec) using the GFDRDSS at a distance of 5 m, and 9 had fine stereovision using the Distance Randot® Stereotest at 3 m. Other subjects described the 100 arcsec-level stereograms correctly. The results exhibited a concordance of stereoacuity within one degrade between the two distance stereotests. Conclusion: The proposed GFDRDSS can alternately project a couple of random-dot stereograms to the subjects' eyes and provide a glasses-free distance stereotest, which showed good concordance with the Distance Randot® Stereotest. More data are needed for statistical studies.

[Effect of repeated horizontal acceleration exposure on cardiac structure in New Zealand rabbits].

Objective: To observe the effects of repeated horizontal -Gx acceleration exposure on cardiac structure in New Zealand rabbits. Methods: Twenty New Zealand rabbits were divided into 2 groups (n=10): control group and -Gx acceleration exposure group. The rabbits in -Gx acceleration exposure group were exposed to -3. 6 Gx with 2 s, at intervals of 5 min, repeated 20 times daily, with a total of 30 d; the control group didn't undergo the acceleration stress. After the last -Gx acceleration exposure, the animals were killed by intravenous injection of air, and two small pieces of myocardium were immediately dissected from the left ventricles for structure examination using optical microscope and transmission electron microscope. Results: There was no significant difference in the myocardial cell morphology and arrangement observed under the optical microscope between the -Gx acceleration exposure group and the control group; the myocardial fibers arranged in disorder, myocardial cell edema, nuclear membrane expansion, vascular endothelial basement membrane separation were observed in the -Gx acceleration exposure group under transmission electron microscope, compared with the control group. Conclusion: -Gx acceleration exposure can lead to ultrastructural damage in rabbit cardiac myocytes. It suggested that the more attention should be paid to the effect and protection of long-term horizontal -Gx acceleration exposure on the cardiac function of carrier fighter pilots.

miR-210 protects renal cell against hypoxia-induced apoptosis by targeting HIF-1 alpha.

The kidney is vulnerable to hypoxia-induced injury. One of the mechanisms underlying this phenomenon is cell apoptosis triggered by hypoxia-inducible factor-1-alpha (HIF-1α) activation. MicroRNA-210 (miR-210) is known to be induced by HIF-1α and can regulate various pathological processes, but its role in hypoxic kidney injury remains unclear. Here, in both kinds of rat systemic hypoxia and local kidney hypoxia models, we found miR-210 levels were upregulated significantly in injured kidney, especially in renal tubular cells. A similar increase was observed in hypoxia-treated human renal tubular HK-2 cells. We also verified that miR-210 can directly suppress HIF-1α expression by targeting the 3' untranslated region (UTR) of HIF-1α mRNA in HK-2 cells in severe hypoxia. Accordingly, miR-210 overexpression caused significant inhibition of the HIF-1α pathway and attenuated apoptosis caused by hypoxia, while miR-210 knockdown exerted the opposite effect. Taken together, our findings verify that miR-210 is involved in the molecular response in hypoxic kidney lesions in vivo and attenuates hypoxia-induced renal tubular cell apoptosis by targeting HIF-1α directly and suppressing HIF-1α pathway activation in vitro.

[Study on fatigue of pilots during simulated flight training based on electroencephalogram].

OBJECTIVE: To study EEG during simulated flight training, then to explore the situational character of mental fatigue of the pilots. METHODS: Fifty male pilots were randomly choice to be recorded their EEG including rest,flight and recovery phase. Then the band waves of EEG were analysed among the three phase. RESULTS: (1) During flight, the amplitude of alpha, beta, SMR, theta, gamma waves tended to increase. These changes seemed obviously in SMR, theta waves. (2) After flight, all the amplitude of the waves declined except for beta wave of the right lobe,and most of them were still higher than those before flight (P < 0.05); (3) The right brain showed a higher cerebration than the left, especially in theta wave. CONCLUSION: Mental fatigue is started during the flight training, and the right lobe has a severe mental fatigue than the left. After flight, mental fatigue showed a slow recovery.

[The effect of PPARalpha signal channel on atorvastatin inhibiting MMP-9 expression in aging myocytes].

OBJECTIVE: To investigate the correlation between atorvastatin inhibiting the expression level of matrix metalloproteinase 9 (MMP-9) and peroxisome proliferator activated receptor alpha (PPARalpha) signal channel in myocyte of aging rat. METHODS: Primary cultures of myocyte were got ten from aging rats. Myocyte were divided into control group, DMSO group, atorvastatin group, atorvastatin plus GW6471 group, which treated respectively by cell culture medium, DMSO, atorvastatin, atorvastatin plus GW6471. The expression of MMP-9 mRNA was evaluated by RT-PCR, and content of MMP-9 protein was detected by Western blot. RESULTS: (1) There was no difference between control group and DMSO group in level of MMP-9 mRNA and protein expression (P > 0.05); (2) The level of MMP-9 mRNA and MMP-9 protein expression in atorvastatin group were significantly lower than those in control group (P < 0.01); (3) Both level of MMP-9 mRNA and protein expression in atorvastatin plus GW6471 group were significantly higher than those in atorvastatin group (P < 0.05), but were still lower than those in control group (P < 0.05). CONCLUSION: Atorvastatin inhibit MMP-9 expression of aging myocytes by PPARalpha signal channel.

[Rapid inhibitory effect of glucocorticoids on peak of [Ca2+]i and PLC in airway smooth muscle].

OBJECTIVE: In this study, we pretreated the mice ASMCs by dexamethasone (Dex) within 10 min, to test the peak of [Ca2+]i and phospho-PLCbeta (ser1105) in the cells by treated with Ach. METHODS: The peak of [Ca2+]i was measured by Fura-2/AM methods and the phospho-PLCbeta-ser1105 was by Western blot, and compared with dexamethasone pretreated groups. Glucocorticoid receptor antagonist RU486 and the protein synthesis inhibitor cycloheximide groups were settled in our study. RESULTS: Glucocorticoids (GCs) significantly decreased the resting values and peak of [Ca2+]i elevation and elevated the intracellular levels of phospho-PLCbeta (ser1105) in 10 min. Neither the RU486 nor cycloheximide could alter the inhibitory effects of glucocorticoids stated above. CONCLUSION: Our results demonstrate that glucocorticoids exert rapid inhibitory effects. The series of signal changes in this process that restrain the peak of [Ca2+]i may be responsible for the rapid nongenomic inhibitory effects of GCs by reducing the activity of PLC.