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Background/Aims: Parkinson’s disease (PD) is a prevalent disease that leads to motor and cognitive disabilities, and oxidative stress (OS) injury was found to be related to the etiology of PD. Increasing evidence has shown that SHC3 is aberrantly expressed in neurons. The current study examines the involvement of SHC3 silencing in OS injury in the nigral dopamine neurons in rats with PD via the PI3K-AKT-FoxO signaling pathway. Methods: To study the mechanisms and functions of SHC3 silencing in PD at the tissue level, 170 rats were selected, and a lentivirus-based packaging system was designed to silence SHC3 expression in rats. Furthermore, PC12 cells were selected for in vitro experimentation. To evaluate the effect of SHC3 silencing in nigral dopamine neuronal growth, an MTT assay, propidium iodide (PI) single staining and Annexin V-PI double staining were performed to detect cell viability, cell cycle progression and cell apoptosis, respectively. Results: SHC3 shRNA led to decreased SOD and MDA levels and enhanced GSH activity, indicating that SHC3 silencing leads to motor retardation. SHC3 silencing repressed the extent of Akt and FoxO phosphorylation, thereby inhibiting the PI3K-AKT-FoxO signaling pathway. Furthermore, in cell experiments, SHC3 silencing suppressed PC12 cell proliferation and cell cycle progression, whereas it enhanced cell apoptosis. Conclusion: The current study provides evidence suggesting that SHC3 silencing may aggravate OS injury in nigral dopamine neurons via downregulation of the PI3K-AKT-FoxO signaling pathway in PD rats.

The migration behavior of silicone molecules including octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane and dodecamethylcyclohexasiloxane (denoted as D4, D5, D6, respectively) for silicone rubber baking mold (SRBM) under two different baking methods into food simulants and to cakes were investigated. Meantime, different daily used oils including corn, peanut, sunflower and butter were used to investigate the effects of oil property on migration of D4, D5 and D6, respectively where cakes were baked using SRMB at 175 °C for 30 min. Results showed that for olive oil, the migration of D4, D5 and D6 reached maximum in 240 min at 175°C under electric baking condition and reached maximum in 20 min at 800 W under microwaving baking. Unlike olive oil, the migration rate of D4, D5 and D6 into Tanex® decreased significantly with used times under both electric baking and microwaving methods. Importantly, results also showed that the amounts of D4, D5 and D6 in cakes baked with peanut oil and corn oil were significantly higher (p

Shot peen forming different from shot peening is a metal forming process widely used in aeronautical industry. Different types of tension-tension fatigue specimens after peen forming were tested. The results show that the fatigue life of specimens peen formed with large balls except edges is 35.4% higher than that of unpeened specimens, while the life of the specimens with whole surface peen formed is 23.2% lower than that of the unpeened specimens. In addition, shot peening specimens which have been peen formed as a surface strengthening way can significantly improve the fatigue resistance. Moreover, when the specimen is peen formed except edges, the position of crack source is from the indentation region to subsurface.

In the present experiment, effects of sodium hydrosulfide (NaHS), a H2S donor, on the oxidative damage, antioxidant capacity and the growth of cucumber hypocotyls and radicles were studied under 100 mmol L−1 NaCl stress. NaCl treatment significantly induced accumulation of H2O2 and thiobarbituric acid-reactive substances (TBARS) in cucumber hypocotyls and radicles, and application of NaHS dramatically reduced the accumulation of H2O2 and lipid peroxidation. However, the alleviating effects greatly depended on the concentrations of NaHS, and 400 μmol L−1 NaHS treatment showed the most significant effects. Corresponding to the change of lipid peroxidation, higher activities of antioxidant enzymes as well as the antioxidant capacity indicated as DPPH scavenging activity, chelating activity of ferrous ions and hydroxyl radical (·OH) scavenging activity were induced by NaHS treatment under NaCl stress, especially by 400 μmol L−1 NaHS treatment. With the alleviating lipid peroxidation, the amylase activities in cotyledons were increased, and the length of cucumber hypocotyls and radicles were significantly promoted by NaHS treatment under NaCl stress. Unlike the effects of NaHS, pretreatment with other sodium salts including Na2S, Na2SO4, NaHSO4, Na2SO3, NaHSO3 and NaAc did not show significant effects on the growth of cucumber hypocotyls and radicles. These salts do not release H2S. Based on above results, it can be concluded that the effects of NaHS in the experiment depended on the H2S rather than other compounds derived from NaHS, and the alleviating effects might related with its function in modulating antioxidant capacity and amylase activities.

To increase oil accumulation in the high-biomass vegetative organs of tobacco ( Nicotiana tabacum L.) plants for renewable production of biofuels, VgDGAT1a isolated from developing seeds of Vernonia galamensis L. was ectopically overexpressed in tobacco leaves using a constitutive promoter. The transgenic tobacco leaves showed a 3.5–5.0-fold increase in oil content compared to the control, with a maximum increase of 9.2% (DW). The transgenic leaves also showed a substantial change in fatty acid composition, with significant enhancement of linoleic acid (18 : 2) and notable reduction of -linolenic acid (18 : 3). The overexpression of VgDGAT1a exhibited no deleterious effect on other phenotypes in the tobacco plant. These results will facilitate development of a novel system for lipid metabolic engineering in vegetative organs of plants, as well as provide a platform for the production of biofuels using the vegetative organs of commercial non-food crops.

A new fluorogenic and chromogenic probe rhodamine B spirolactam (1) was developed that in aqueous solutions exhibited a highly selective and sensitive "turn-on" type spectral response toward NO detection following a NO-induced spiro-ring opening reaction in 1.

Adventitious shoots were successfully regenerated from hypocotyl explants of in vitro cultures of Euonymus japonicus Cu zhi. Hypocotyl slices were cultured on Murashige and Skoog (MS) and B 5 basal medium supplemented with varied concentration of different plant growth-regulators, e.g., α-naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA) in combination with 6-benzylaminopurine (6-BA) and kinetin. The study showed that shoots could be directly regenerated from hypocotyl explants without the intervening callus phase; MS medium was more suitable for adventitious shoots regeneration. The ability of hypocotyls segments to produce shoots varied depending upon their position on the seedlings. The highest regeneration rate was obtained with hypocotyl segments near to the cotyledon cultured on MS basal medium supplemented with 1.5 mg L −1 6-BA and 0.05 mg L −1 NAA (63.64%). The regenerated shoots were readily elongated on the same medium as used for multiplication and rooted on half-strength MS basal medium supplemented with 1.0 mg L −1 IBA and 100 mg L −1 activated carbon. After being transferred to greenhouse conditions, 96% of the plantlets were successfully acclimatized. This regeneration system is applied for genetic transformation now.

A new highly sensitive and selective colorimetric method for fluoride determination in water is described. The novel reagent used is a hemicyanine dye (HC), which forms a stable complex with Zr-EDTA, the fluoride-binding site, through the hydroxyl groups. The hemicyanine-chelating Zr-EDTA complex (HC-Zr-EDTA) is ready to react with fluoride ion to release HC. This result in remarkable color change of the sensing solutions from red (lambda(max)=513nm) to yellow (lambda(max)=427nm) at pH 4.40. When applied to the colorimetric determination of fluoride ions, a linear range from 3.0x10(-6) to 5.0x10(-5)mol/L and a detection limit of 2.8x10(-6)mol/L with a correlation coefficient of 0.9993 can be achieved under the optimized conditions. Because of the specific affinity of fluorides for the [Zr-EDTA], there is little interference by other ions. This method has been successfully applied to the determination of fluorides in toothpaste samples.

A novel spirocyclic compound (4R)-4-(4-hydroxy-benzyl) spiro [4,5] dec-1-en-8-ol (sequosempervirin A) was isolated from the branches and leaves of Sequoia sempervirens. Its structure and relative stereochemistry were mainly determined by MS, 2D NMR and X-ray means, which is the first naturally occurring norlignan containing one spirocycle with C6 (cyclohexane)-C2-C3-C6 skeleton. (C) 2004 Elsevier Ltd. All rights reserved.

The title compound, C37H36N4O2, has been obtained by the reaction of 2-[3,6-bis­(diethyl­amino)-9H-xanthen-9-yl]benzoyl chloride with 8-amino­quinoline. The mol­ecular packing in the crystal structure is stabilized by weak C—H⋯O hydrogen bonding.