Identification and characterization of genes associated with tapping panel dryness from Hevea brasiliensis latex using suppression subtractive hybridization

<p>Abstract</p> <p>Background</p> <p>Tapping panel dryness (TPD) is one of the most serious threats to natural rubber production. Although a great deal of effort has been made to study TPD in rubber tree, the molecular mechanisms underlying TPD remain poorly understood. Identification and systematical analyses of the genes associated with TPD are the prerequisites for elucidating the molecular mechanisms involved in TPD. The present study is undertaken to generate information about the genes related to TPD in rubber tree.</p> <p>Results</p> <p>To identify the genes related to TPD in rubber tree, forward and reverse cDNA libraries from the latex of healthy and TPD trees were constructed using suppression subtractive hybridization (SSH) method. Among the 1106 clones obtained from the two cDNA libraries, 822 clones showed differential expression in two libraries by reverse Northern blot analyses. Sequence analyses indicated that the 822 clones represented 237 unique genes; and most of them have not been reported to be associated with TPD in rubber tree. The expression patterns of 20 differentially expressed genes were further investigated to validate the SSH data by reverse transcription PCR (RT-PCR) and real-time PCR analysis. According to the Gene Ontology convention, 237 unique genes were classified into 10 functional groups, such as stress/defense response, protein metabolism, transcription and post-transcription, rubber biosynthesis, etc. Among the genes with known function, the genes preferentially expressed were associated with stress/defense response in the reverse library, whereas metabolism and energy in the forward one.</p> <p>Conclusions</p> <p>The genes associated with TPD were identified by SSH method in this research. Systematic analyses of the genes related to TPD suggest that the production and scavenging of reactive oxygen species (ROS), ubiquitin proteasome pathway, programmed cell death and rubber biosynthesis might play important roles in TPD. Therefore, our results not only enrich information about the genes related to TPD, but also provide new insights into understanding the TPD process in rubber tree.</p

A Palladium-Catalyzed Carbonylative Acetylation of <i>N</i>‑Phenylpyridin-2-amine Using DMF and CO as the Acetyl Source

This study reports a carbonylative acetylation for the synthesis of N-phenyl-N-(pyridin-2-yl)acetamides using N,N-dimethylformamide (DMF) as a methyl source and CO as a carbonyl source. Interestingly, dimethyl sulfoxide (DMSO) can be also used as a methyl source when using only DMSO as the solvent. Mechanistic studies using DMSO-d6 revealed that the methyl group was derived from the methyl group of DMF instead of DMSO when using DMF and DMSO as a mixed solvent. These results indicated that DMF was a preferential methyl source

Oxygen therapy in patients with retinal artery occlusion: A meta-analysis.

BACKGROUND:Oxygen therapy has been widely used for RAO (retinal artery occlusion) patients; however, inconsistent results have been reported. METHODS:PubMed, Web of Science, EMBASE, Medline (OvidSP), Cochrane, China National Knowledge Infrastructure (CNKI), and Wanfang Database were examined. The primary endpoint was visual acuity (VA), and RevMan software 5.3 was used to statistically analyze the outcomes. RESULTS:Seven randomized controlled trials (RCTs) met the inclusion criteria. Patients who received oxygen therapy exhibited probability of visual improvement about 5.61 times compared with the control group who did not receive oxygen therapy (OR = 5.61; 95% CI, 3.60-8.73; p < 0.01). No statistically significant difference was observed between oxygen inhalation methods (Chi2 = 0.18, df = 1, p = 0.67), combined therapy (Chi2 = 0.21, df = 1, p = 0.64), or RAO type (Chi2 = 0.06, df = 1, p = 0.81). Conversely, 100% oxygen (Chi2 = 4.55, df = 1, p < 0.05) and hyperbaric oxygen (Chi2 = 4.55, df = 1, p < 0.05) significantly improved VA in RAO patients. Better effect was showed in period within 3 months (Chi2 = 5.76, df = 1, p < 0.05). The most effective treatment length was over 9 hours (Chi2 = 6.58, df = 1, p < 0.05). CONCLUSION:Oxygen therapy demonstrated beneficial effects in improving VA in RAO patients, particularly when patients were treated with 100% hyperbaric oxygen and for over 9 hours

Effects of autophagy inhibitor or activator on PAs-induced cell apoptosis.

<p>(<b>a</b>) Senecionine (12.5 μM), (<b>b</b>) seneciphylline (12.5 μM), (<b>c</b>) clivorine (12.5 μM) and (<b>d</b>) monocrotaline (12.5 μM) treated or untreated Huh-7.5 cells were pre-cultured in the presence of autophagy inhibitor 3-MA (5 mM)) or activator Rapa (100 nM) for 2 h, and then cell apoptosis were subjected to flow cytometry analyses. The data shown in 9a, 9b, 9c and 9d are the mean ± SD of the results of three independent experiments. The <i>P</i> value was calculated by Student’s <i>t</i>-test (^*<i>P</i> < 0.05).</p