본 논문에서는 약용매에서 용해될 수 있는 지방산 변성 에폭시수지를 합성하였고, 합성한 수지 의 용해도 평가가 이루어졌다. 지방산 변성 에폭시수지를 합성하기 위하여 비스페놀A형, 페놀 노볼락형 및 오르소 크레졸 노볼락형의 3종류 에폭시수지를 사용하였고, 여기에 지방산, dodecyl phenol (DP), toluene diisocyanate (TDI)를 도입하였다. 합성조건은 당량기준으로 에폭시수지/지방산 = 1/0.5, 지방산/DP = 0.25/0.25, TDI 0.5이었고, 에폭시수지 종류에 따라 12종류의 지방산 변성 에폭시수지가 합성되었다. 합성 된 지방산 변성 에폭시수지에 대하여 점도 및 용매√가용성을 평가한 결과, 벤젠고리와 글리시딜기의 함량 및 알킬기의 탄소수가 증가할수록 약용매에 대한 용해성이 우수한 것으로 나타났다. 또한 약용매에 용해성 이 우수한 지방산 변성 에폭시수지를 사용하여 투명 도료를 제조하여 물성을 평가한 결과, 비스페놀A형 에 폭시수지/지방산/DP/TDI의 당량비가 1.0/0.25/0.25/0.5인 것과 페놀 노볼락형 에폭시수지/지방산/DP의 당량비가 1.0/0.25/0.25인 조성에서 건조시간, 접착력, 도막경도, 내충격성, 내알칼리성에서 양호한 물성을 나타내었다.
MicroRNAs (miRNAs) are approximately 22 nucleotides of small noncoding RNAs that control gene expression at the posttranscriptional level through translational inhibition and destabilization of their target mRNAs. The miRNAs are phylogenetically conserved and have been shown to be instrumental in a wide variety of key biological processes including cell cycle regulation, apoptosis, metabolism, imprinting, and differentiation. Recently, a paper has shown that expression of the miRNA-302/367 cluster expressed abundantly in mouse and human embryonic stem cells (ESCs) can directly reprogram mouse and human somatic cells to induced pluripotent stem cells (iPSCs) efficiently in the absence of any of the four factors, Oct4, Sox2, c-Myc, and Klf4. To apply this efficient method to porcine, we analyzed porcine genomic sequence containing predicted porcine miRNA-302/367 cluster through ENSEMBL database, generated a non-replicative episomal vector system including miRNA-302/367 cluster originated from porcine embryonic fibro-blasts (PEF), and tried to make porcine iPSCs by transfection of the miRNA-302/367 cluster. Colonies expressing EGFP and forming compact shape were found, but they were not established as iPSC lines. Our data in this study show that pig miRNA-302/367 cluster could not satisfy requirement of PEF reprogramming conditions for pluripotency. To make pig iPSC lines by miRNA, further studies on the role of miRNAs in pluripotency and new trials of transfection with conventional reprogramming factors are needed.
The toxicity of red pine needle hydrodistillate, its constituents, and 12 structurally related compounds to third instar larvae of insecticide-susceptible Aedes aegypti and wild Aedes albopictus was examined using a direct-contact bioassay. Results were compared with those of the currently used larvicides fenthion and temephos. The red pine needle hydrodistillate constituents were identified by GC-MS and co-elution of authenticated samples following co-injection. Based on 24 h LC50 values, 3-carene (8.60–9.33 mg/L), limonene (10.34–10.77 mg/L), and thymol (10.65–11.45 mg/L) were the most toxic constituents. The moderate toxicity was produced by (1S)-(–)-α-pinene, p-cymene, geranyl acetate, myrcene, and β -caryophyllene (LC50, 27.62–38.01 and 28.61–39.52 mg/L). Overall, these compounds were less effective than either fenthion (LC50, 0.012–0.022 mg/L) or temephos (LC50, 0.010–0.015 mg/L). In the light of global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment, red pine needle hydrodistillate and the compounds described merit further study as potential larvicides for the control of mosquito populations.