[Measurement and research status of stable hydrogen isotopes in tree-ring lignin methoxyl groups]. / æ ‘è½®æœ¨è´¨ç´ ç”²æ°§åŸºç¨³å®šæ°¢åŒä½ç´ æ¯”çŽ‡æµ‹å®šæ–¹æ³•ç ”ç©¶è¿›å±•.

The primary hydrogen (H) source for all organic compounds in the biosphere is from water, and then participates in biogeochemical cycles through photosynthesis and plant physiological metabolism. As a new proxy of paleoclimate and paleoenvironment, stable hydrogen isotope ratios in wood lignin methoxyl groups (δ2HLM) show great advantages in the studies of paleoclimatic change and have been used to reconstruct precipitation stable hydrogen isotope ratios and paleoclimate signals in many regions. Based on the lignin application mechanism and analysis method of δ2HLM, we evaluated the stability and effectiveness of δ2HLM-measurement method from lignin content and lignin monomer composition, and expounded the tree lignin methoxyl groups' stable isotope proxies of current research outcomes. In the middle latitudes, the tree-ring δ2HLM had great potential in recording temperature signals and precipitation stable hydrogen isotope ratios. However, the study of tree-ring δ2HLM was still in its infancy as evidenced by following reasons: 1) The study area was limited to the middle latitude of the northern hemisphere, and the study subjects were limited to conifer species; 2) To compensate for the limitation of hydrogen isotopic records of nitrocellulose, high resolution tree-ring δ2HLM would be studied; 3) The potential of tree-ring δ2HLM utilization in plant physiology and forest ecology remained to be exploited.

Effects of Decabromodiphenyl Ether and Elevated Carbon Dioxide on Rice (Oryza sativa L.).

We assessed the effects of carbon dioxide (CO2) and decabromodiphenyl ether (BDE-209, 0, 3 and 30 mg/kg) on rice (Oryza sativa L. cv. Wuyunjing) in field free-air CO2 enrichment system. Rice at elevated (580 ppm) CO2 had increased net photosynthetic rate, intercellular CO2 concentration, shoot biomass, yield and phosphorus content in grains. However, there were no significant changes in such parameters observed on rice at elevated CO2 combined with BDE-209 (3 and 30 mg/kg). Elevated CO2 alone had no significant effects on sugar or starch content in rice grains, whereas its combination with BDE-209 (3 mg/kg) significantly decreased grain sugar and starch content. In conclusion, rice reared in soil polluted by BDE-209 under elevated CO2 modulates the effects in grain feature.

Design, synthesis and antitumor activity of aromatic urea-quinazolines.

Background: Gefitinib and sorafenib have been proved effective for the treatment of cancers in clinical practice for years. Materials & methods: We intended to integrate the structural features of gefitinib and sorafenib and construct structurally unique 7-aromatic ureido-4-anilinoquinazolines. Results: Most of the targets exhibited promising antitumor activities. 8u showed excellent antitumor activities against the three tested cell lines (IC50, 0.81-2.49 µM). The enzymatic, apoptosis assay of 8u were also performed to study their preliminary action of mechanism. Conclusion: 8u deserve further research as antitumor agents.

[Effects of elevated ozone concentrations on enzyme activities and organic acids content in wheat rhizospheric soil.] / O3æµ“åº¦å‡é«˜å¯¹å°éº¦æ ¹é™ åœŸå£¤é ¶æ´»æ€§å’Œæœ‰æœºé ¸å«é‡çš„å½±å“.

The elevated concentration of tropospheric ozone (O3) is an important global climate change driver, with adverse impacts on soil ecological environment and crop growth. In this study, a pot experiment was carried out in an open top chamber (OTC), to investigate the effects of elevated ozone concentration on soil enzyme activities (catalase, polyphenol oxidase, dehydrogenase and invertase), organic acids contents (oxalic acid, citric acid and malic acid) at different growth stages (tillering, jointing, heading and ripening stages) of wheat, and combined with the rhizospheric soil physicochemical properties and plant root characteristics to analyze the underlying reasons. The results showed that, elevated ozone concentration increased soil catalase, polyphenol oxidase, dehydrogenase and invertase activities at wheat ripening period to different degrees, with the effects on the activities of catalase and polyphenol oxidase being statistically significant. At the heading stage, activities of dehydrogenase and invertase were significantly increased by up to 76.7%. At the ripening stage, elevated ozone concentration significantly increased the content of citric acid and malic acid and redox potential (Eh) in rhizospheric soil, but reduced soil pH, electrical conductivity, total carbon and nitrogen. For root characteristics, elevated ozone concentrations significantly reduced the wheat root biomass, total root length and root surface area but increased the average root diameter.

[Effects of UV radiation on the aggregation performance of small molecular organic acids].

This study systematically investigated the effects of UV radiation on the aggregation of small molecular aliphatic carboxylic acids and phenolic acids by jar test. Experimental results show that solution pH has little effect on the coagulation of small molecular aliphatic carboxylic acids including citric acid, oxalic acid, tartaric acid, and succinic acid. For the solutions pretreated with UV light, the removal rates of the selected aliphatic carboxylic acids in coagulation are higher than that without UV radiation. Further study shows that photochemical reactions occur during UV radiation which decreases the negative charge in aliphatic carboxylic acids, and thereby increases their aggregation properties. Different from aliphatic carboxylic acids, phenol, salicylic acid, and benzoic acid have poor coagulation properties, and UV radiation does not have notable effects on their aggregation in the coagulation process. The coagulation performance of tannic acid is better than the other phenolic acids. At pH = 6, its removal rate is above 90%, which may be contributed to the aliphatic carboxylic acid structure in its molecular. Meanwhile, the large molecular of tannic acid is also easier to be adsorbed by the hydrolysis products of PAC1.

[Dapoxetine in treatment of premature ejaculation: a systematic review].

OBJECTIVE: To assess the effectiveness of dapoxetine in the treatment of premature ejaculation. METHODS: Both English and Chinese studies involving men with prematrue ejaculation who were treated with dapoxetine from the Cochrane Library, MEDLINE, EMBASE and CNKI, CBM, VIP between 1979 and 2009.were included in the randomized controlled trials (RCTs) and the data processed by RevMan. RESULTS: Five RCTs involving 4433 patients were included in the Meta analysis, of which 3 were of grade A and 2 were of grade B according to the quality evaluation of methodology. Intravaginal ejaculatory latency time (IELT), patient-reported global impression of change (PGI), satisfaction with sexual intercourse (SWSI), perceived control over ejaculation (PCOE), personal distress related to ejaculation (PDRE) were used for assessment. Meta analysis based on included studies of patients having been treated with dapoxetine for 9-24 weeks showed that: (1) the difference of the patients' IELT between treatment group and control group was statistically significant [P<0.001, WMD (95%CI) was 1.38 (1.21,1.55)]; (2) the difference of the PGI of development in premature ejaculation between treatment group and control group was statistically significant [P<0.001, OR (95%CI) was 3.56 (2.60,4.88)]; (3) the difference of the patients' SWSI between treatment group and control group was statistically significant [P<0.001, OR (95%CI) was 3.85 (2.08,7.10)]; the difference of the patients' score of SWSI between treatment group and control group was statistically significant [P<0.001, WMD (95%CI) was 0.55 (0.48,0.62)]; (4) the difference of the patients' change of PCOE between treatment group and control group was statistically significant [P<0.001, OR (95%CI) was 2.87(2.30,3.58)]; the difference of the patients' score of PCOE between treatment group and control group was statistically significant [P<0.001, WMD (95%CI) was 0.63(0.49,0.78)]; (5) after being treated with dapoxetine for 9-24 weeks, the difference of the patients' change of PDRE between treatment group and control group was statistically significant [P<0.001, OR (95%CI) was 2.02 (1.69,2.42)]. All the RCTs reported the side effects of dapoxetine, but the results showed that there were no serious side effects of dapoxetine during the treatment period. CONCLUSION: The available evidence indicates that dapoxetine would improve the symptoms of premature ejaculation, prolong IELT over 9-24 weeks in men from a wide range of cultural backgrounds, and significantly improve all patients' reported outcomes and the patients' clinical global impressions of premature ejaculation, including more control, greater satisfaction, and less distress.