• Applied Biological Chemistry
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• v.40 no.2
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• pp.139-143
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• 1997

This research aims at developing a new pesticide by means of synthesizing new 2-iminothiazoline derivatives and testing their bilolgical activity. In an effort to prepare 2-iminothiazolines, primary amines were treated to have reaction with isothiocyanate, followed by a treatment of ${\alpha}-halo$ ketone derivatives. Their antifungal activaty was tested against six different plant diseases. A compound that has a phenylimino group at C-2, methyl at C-3, phenylcarbamoylmethyl at C-4, and hydrogen at C-5 on the thiazoline skeleton was found to be most active.

• Korean Journal of Pharmacognosy
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• v.35 no.3 s.138
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• pp.259-263
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• 2004

Twelve constituents were isolated from the MeOH extract of the root of Brassica campestris L. ssp rapa. They were identified as linoleic acid methylester (1), palmitic acid (2), ${\beta}-sitosterol$ (3), 1-methoxyindole-3-acetonitrile (4), indole-3-acetonitrile (5), linolenic acid (6), goitrin (7),4-hydroxycinnamyl alcohol (8), coniferyl alcohol (9), p-coumaroylglucose (11) and feruloylglucose (12), on the basis of spectral data respectively.

• Natural Product Sciences
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• v.22 no.3
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• pp.209-215
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• 2016

Kigelia africana (Lam.) Benth. (Bignoniaceae) is a flowering plants in South, Central and West Africa and commonly known as the sausage tree (Eng.); worsboom (Afr.); umVunguta, umFongothi (Zulu); Modukguhlu (North Sotho); Muvevha (Venda). The dried, powdered fruits are used as dressing for wounds and ulcers, haemorrhoids, rheumatism, purgative, skin-firming, lactation in breast-feeding mothers. The aim of this study is to investigate the cytotoxic and apoptotic potentials of 70% ethanolic extracts of Kigelia africana fruits in HCT116 human colon cancer cells. Treatment of Kigelia africana fruits with various concentrations resulted in a sequence of characteristic of apoptosis, including loss of cell viability and morphological changes. Flow cytometry analysis showed Kigelia africana fruits increased the sub-G1 phase (apoptosis) population. Apoptosis confirmed by annexin V-fluorescein isothiocyanate and propidium iodide double staining in HCT116 human colon cancer cell lines. Moreover, analysis of the mechanism indicated that Kigelia africana fruits showed an increased Bax and Bcl-2 expressions in a dose-dependent manner, resulting in activation of hallmarks of apoptotic events, caspase-3, caspase-9 and cleaved poly-ADP-ribose polymerase. This is the first report to demonstrate the cytotoxicity of Kigelia africana fruits on HCT116 human colon cancer cells.

• The Plant Pathology Journal
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• v.32 no.4
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• pp.340-346
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• 2016

To understand how Bursaphelenchus xylophilus kills pine trees, the differences between the effects of B. xylophilus and B. mucronatus on pine trees are usually compared. In this study, the migration and attacking ability of a non-pathogenic B. mucronatus in Pinus thunbergii were investigated. The distribution of B. mucronatus and the number of dead epithelial cells resulting from inoculation were compared with those of the pathogenic B. xylophilus. Although B. mucronatus is non-pathogenic in pines, its distribution pattern in P. thunbergii was the same as that of B. xylophilus. We therefore concluded that the non-pathogenicity of B. mucronatus could not be attributed to its migration ability. The sparse and sporadic attacking pattern of B. mucronatus was also the same as that of B. xylophilus. However, the number and area of the dead epithelial cells in pine cuttings inoculated with B. mucronatus were smaller than in those cuttings inoculated with B. xylophilus, meaning that the attacking ability of B. mucronatus is weaker than that of B. xylophilus. Therefore, we concluded that the weaker attacking ability of B. mucronatus might be the factor responsible for the non-pathogenicity.

• The Journal of Korean Society of Virology
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• v.27 no.1
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• pp.49-57
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• 1997

We developed a sensitive, nested reverse transcription-polymerase chain reaction (RT-PCR) to detect Hantaan, Seoul, Belgrade, Puumala and Sin Nombre viruses in animal tissues. Total RNA was extracted from blood, lung or kidney samples of experimentally-infected hamsters by using the guanidine isothiocyanate buffer-acid phenol-chloroform method. Genus-reactive outer primers were derived from the consensus region of the G1 gene sequences of several hantaviruses. Serotype-specific primers were selected within the region amplified by the outer primers. To examine the sensitivity and specificity of the test, we diluted known quantities of Hantaan, Seoul, Belgrade, Puumala and Sin Nombre viruses in human or hamster immune sera before performing the nested RT-PCR. We could detect as little as 1 pfu of virus, even in the presence of high-titer neutralizing antibodies, and the serotype-specific primers amplified only homologous serotype viruses. RT-PCR with these primers demonstrated virus in the blood of experimentally-infected hamsters as early as four days to as late as 30 days after infection. A comparison of a standard immunofluorescent antibody screening test (IFAT) to nested RT-PCR with RNA extracted from lung or kidney tissues of the hamsters, demonstrated that RT-PCR to be more sensitive for identifying viruses in these tissues.

• Biomolecules & Therapeutics
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• v.26 no.2
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• pp.182-190
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• 2018

The objective of this work is to evaluate the effect of polyamidoamine (PAMAM) dendrimers on electroosmotic flow (EOF) through skin. The effect of size and concentration of dendrimer was studied, using generation 1, 4 and 7 dendrimer (G1, G4 and G7, respectively). As a marker molecule for the direction and magnitude of EOF, a neutral molecule, acetoaminophen (AAP) was used. The visualization of dendrimer permeation into the current conducting pore (CCP) of skin was made using G4-fluorescein isothiocyanate (FITC) conjugate and confocal microscopy. Without dendrimer, anodal flux of AAP was much higher than cathodal or passive flux. When G1 dendrimer was added, anodal flux decreased, presumably due to the decrease in EOF by the association of G1 dendrimer with net negative charge in CCP. As the generation increased, larger decrease in anodal flux was observed, and the direction of EOF was reversed. Small amount of methanol used for the preparation of dendrimer solution also contributed to the decrease in anodal flux of AAP. Cross-sectional view perpendicular to the skin surface by confocal laser scanning microscope (CLSM) study showed that G4 dendrimer-FITC conjugate (G4-FITC) can penetrate into the viable epidermis and dermis under anodal current. The permeation route seemed to be localized on hair follicle region. These results suggest that PAMAM dendrimers can permeate into CCP and change the magnitude and direction of EOF. Overall, we obtained a better understanding on the mechanistic insights into the electroosmosis phenomena and its role on flux during iontophoresis.

• Journal of the korean society of oceanography
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• v.34 no.3
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• pp.167-171
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• 1999

Since toxic Alexandrium catenella and non-toxic A. fraterculus are morphologically similar, they are difficult to discriminate under the light microscope. However, a novel technology, such as fluorescein isothiocyanate (FITC)-conjugated lectin probes enables easy and rapid differentiation. Toxic A. catenella bound seven different lectins, whereas the non-toxic A. fratercuzus did not bind Arachis hypogaea (PNA) lectin. In addition, Pseudo-nitrschia species in this study were also difficult to identify to species level with light microscope techniques, but it was possible to classify them using fluorescent lectins. Pseudo-nitzschia multistriata, P. subfraudulenta and P. pungens bound Canavalia ensiformis (ConA), whereas P. subpaclfica did not, and P. pungens also bound Ricinus communis (RCA). These results imply that lectin could be used as a critical tool in the differentiation of P. multistriata, P. subfraudulenta and P. pungens. However, P. subpacifica was not differentiated by the lectins tested. Therefore, it isconcluded that lectin probes are useful for discriminating toxic A. catenella from non-toxic A. fraterculus, and for the identification of some Pseudo-nitzschia species. In addition, this method has a great potential to speed and detection between non-toxic and toxic harmful algal blooms (HABs) in Korean biotoxin monitoring systems.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.55-59
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• 2012

Treatments of organic isothiocyanates (R-NCS) with $NaN_3$ in the presence of pyridine in water at room temperature gave corresponding various organic tetrazole-thiones, [$S=CN_4(R)$] (R = alkyl or aryl). Isolated products are obtained as white or yellow solids in good yields (76-97%). The molecular structure by X-ray diffraction study for one of products shows the proposed formation. In addition, one-pot synthesis of 1-substituted 5-alkyl(or aryl)sulfanyltetrazoles has been demonstrated. Addition of alkyl or aryl halides into the mixture of organic isothiocyanates, $NaN_3$, and pyridine in water at room temperature exclusively formed 1-substituted 5-alkyl(or aryl)sulfanyltetrazoles (S-derivatives) in high yields.

• Journal of Biomedical Engineering Research
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• v.41 no.1
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• pp.62-66
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• 2020

Controlled drug release is important for effective treatment of cancer. Poly(DL-lactide-co-glycolide) acid (PLGA) is a Food and Drug Administration (FDA) approved polymer and have been extensively studied as drug delivery carriers with biodegradable and biocompatible properties. However, PLGA drug delivery carriers are limited due to the initial burst release of drug. Certain drugs require an early rapid release, but in many cases the initial rapid release can be inefficient, reducing therapeutic effects and also increasing side effects. Therefore, sustained release is important for effective treatment. Poly Lactic Acid stereo complex (PLA SC) is resistant to hydrolysis and has high stability in aqueous solutions. Therefore, in this work, PLGA based discoidal polymeric particles are modified by Poly Lactic Acid stereocomplex (PLAsc DPPs). PLAsc DPPs are 3 ㎛ in diameter, also showing a relatively sustained release profile. Fluorescein 5(6)-isothiocyanate (FITC) released from PLAsc DPPs was continuously observed until 38 days, which showed the initial release of FITC from PLAsc DPPs was about 3.9-fold reduced as compared to PLGA based DPPs at 1 hour.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4109-4116
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• 2012

An efficient solid-phase methodology has been developed for the synthesis of 2-amino and 2-amidobenzo[d]-oxazole derivatives. The key step in this procedure involves the preparation of polymer-bound 2-aminobenzo-[d]oxazole resins 4 by cyclization reaction of 2-hydroxy-phenylthiourea resin 3. The resin-bound 2-hydroxyphenylthiourea 3 is produced by the addition of 2-aminophenol to the isothiocyanate-terminated resin 2 and serve as a key intermediate for the linker resin. This core skeleton 2-aminobenzo[d]oxazole resin 4 undergoes functionalization reaction with various electrophiles, such as alkylhalides and acid chlorides to generate 2-amino and 2-amidobenzo[d]oxazole resins 5 and 6 respectively. Finally, 2-amino and 2-amidobenzo[d]oxazole derivatives 7 and 8 are then generated in good yields and purities by cleavage of the respective resins 5 and 6 under trifluoroacetic acid (TFA) in dichloromethane ($CH_2Cl_2$).