• Journal of the Korean Chemical Society
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• v.25 no.1
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• pp.1-6
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• 1981

Ultraviolet spectrophotometric investigations were carried out on the systems of o-, m-and p-xylene with iodine in carbon tetrachloride. The results reveal the formation of one to one molecular complexes of the type, $C_6H_4(CH_3)_2{\cdot}I_2. $The equilibrium constants of complexes were obtained in consideration of that absorption maxima has the blue shift with the increasing temperatures according to the formation of the charge transfer complexes. The thermodynamic parameters, $ {\Delta}$H, $ {\Delta}$G and $ {\Delta}$S for the formation of the charge transfer complexes were calculated from these values. These results combined with previous study of this series indicated that the relative stabilities of the polymethylbenzene complexes with iodine increase in the order, Benzene < Toluene < o-Xylene < p-Xylene These results are supposed to be the influence resulted from increase of electron density by the positive inductive effect and the steric hindrance effect.

• Polymer(Korea)
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• v.39 no.2
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• pp.225-234
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• 2015

In this study, we proposed to synthesize thermally stable, soluble and conjugated Schiff base polymer (SbP). For this reason, a specific molecule namely 4,4'-thiodiphenol which has sulfur and oxygen bridge in its structure was used to synthesize bi-functional monomers. Bi-functional amino and carbonyl monomers namely 4,4'-[thio-bis(4,1-phenyleneoxy)] dianiline (DIA) and 4,4'-[thiobis(4,1-phenyleneoxy)]dibenzaldehyde (DIB) were prepared from the elimination reaction of 4,4'-thiodiphenol with 4-iodonitrobenzene and 4-iodobenzaldehyde, respectively. The structures of products were confirmed by elemental analysis, FTIR, $^1H$ NMR and $^{13}C$ NMR techniques. The molecular weight distribution parameters of SbP were determined by size exclusion chromatography (SEC). The synthesized SbP was characterized by solubility tests, TG-DTA and DSC. Also, conductivity values of SbP and SbP-iodine complex were determined from their solid conductivity measurements. The conductivity measurements of doped and undoped SbP were carried out by Keithley 2400 electrometer at room temperature and atmospheric pressure, which were calculated via four-point probe technique. When iodine was used as a doping agent, the conductivity of SbP was observed to be increased. Optical band gap ($E_g$) of SbP was also calculated by using UV-Vis spectroscopy. It should be stressed that SbP was a semiconductor which had a potential in electronic and optoelectronic applications, with fairly low band gap. SbP was found to be thermally stable up to $300^{\circ}C$. The char of SbP was observed 29.86% at $1000^{\circ}C$.

• Journal of the Korean Chemical Society
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• v.9 no.4
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• pp.153-160
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• 1965

Ultraviolet spectrophotometric investigations have been carried out on the systems of benzene with iodine, bromine, chlorine and iodine monobromide in carbon tetrachloride. The results reveal the formation of one to one molecular complexes of the type, $C_6H_6{\cdot}X_2\;or\;C_6H_6{\cdot}IX$ (X denotes halogen atoms). The equilibrium constants obtained at $25^{\circ}$for the complex formation are 0.173, 0.137, 0.0643 and 0.341 $lmole^{-1}$ for $C_6H_6{\cdot}I_2,\;C_6H_6{\cdot}Br_2,\;C_6H_6{\cdot}Cl_2\;and\;C_6H_6{\cdot}IBr$, respectively. These results combined with those obtained by other workers indicate that the relative stabilities of the benzene complexes decrease in the order, $ICl > IBr > I_2 > Br_2 > Cl_2.$ This order may be measure of their relative acidities toward benzene, which is explained in terms of the relative polarizabilities of halogen molecules and the relative electronegativities of halogen atoms.

• Korean Journal of Food Science and Technology
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• v.10 no.1
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• pp.57-62
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• 1978

The morphology and chemical properties of bracken (Pteridium aquilinum) root starch were investigated. The starch granules were mainly sphere and cocoon with the diameter of $5-12\mu$. Polarized micrograph indicated that the starch granule had a hilum at the center of granule, showing a crossed-birefringence. X-ray diffraction pattern demonstrated that the granules showed B-type. The density of the starch was 1.49 and the amylose content was 22%. The ferricyanide number and alkali number were 0.292 and 11.03, respectively. Proximate analysis showed that the starch contained 0.52% lipid, 0.63% ash and 150ppm phosphorus of which over 80% were found in the amylopectin fraction. The iodine affinity and molecular weight of amylose were 16.1 and 83,000 respectively. The degree of branching and glucose units per segment of amylopectin were 3.7% and 27, respectively.

• Korean Journal of Radiology
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• v.25 no.3
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• pp.257-266
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• 2024

Objective: To investigate molecular and functional consequences of additional exposures to iodine- or gadolinium-based contrast agents within 24 hours from the initial intravenous administration of iodine-based contrast agents through an animal study. Materials and Methods: Fifty-six Sprague-Dawley male rats were equally divided into eight groups: negative control, positive control (PC) with single-dose administration of CT contrast agent, and additional administration of either CT or MR contrast agents 2, 4, or 24 hours from initial CT contrast agent injection. A 12 µL/g of iodinated contrast agent or a 0.47 µL/g of gadolinium-based contrast agent were injected into the tail vein. Serum levels of blood urea nitrogen, creatinine, cystatin C (Cys C), and malondialdehyde (MDA) were measured. mRNA and protein levels of kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) were evaluated. Results: Levels of serum creatinine (SCr) were significantly higher in repeated CT contrast agent injection groups than in PC (0.21 ± 0.02 mg/dL for PC; 0.40 ± 0.02, 0.34 ± 0.03, and 0.41 ± 0.10 mg/dL for 2-, 4-, and 24-hour interval groups, respectively; P < 0.001). There was no significant difference in the average Cys C and MDA levels between PC and repeated CT contrast agent injection groups (Cys C, P = 0.256-0.362; MDA, P > 0.99). Additional doses of MR contrast agent did not make significant changes compared to PC in SCr (P > 0.99), Cys C (P = 0.262), and MDA (P = 0.139-0.771) levels. mRNA and protein levels of KIM-1 and NGAL were not significantly different among additional CT or MR contrast agent groups (P > 0.05). Conclusion: A sufficient time interval, probably more than 24 hours, between repeated contrast-enhanced CT examinations may be necessary to avoid deterioration in renal function. However, conducting contrast-enhanced MRI on the same day as contrast-enhanced CT may not induce clinically significant kidney injury.

• Korean Journal of Microbiology
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• v.29 no.5
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• pp.301-306
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• 1991

Extracellular fructosyl transferase from Aureobasidium pullulans C-23 was characterized. The molecular weight of the isolated enzyme was determined to be approximately 170,000 by SDS polyacrylamide gel electrophoresis. The enzyme has the pI value of about 3.7. The enzyme was almost completely inhibited by 5mM $Hg^{2+}$ , but was not significantly affected by other cations tested. The enzyme was inactivated by treatment of tryptophan-specific reagent N-bromo- succinimide and tyrosine-specific reagent iodine. The substrate sucrose showed protective effect on the inactivation of the enzyme by the both reagents. These results suggest that tryptophan and tyrosine residues are probably located at or near active site of the enzyme.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.891-894
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• 2013

The present study was performed to assess the activity of the botulinum toxin A on breast cancer cells. The T47D cell line was exposed to diverse concentrations of the botulinum toxin A and cell viability and apoptosis were estimated using MTT and propidium iodine/annexin V methods, respectively. Botulinum toxin A exerted greater cytotoxic activity in T47D cells in comparison with MCF10A normal cells; this appeared to be via apoptotic processes caspase-3 and -7. In conclusion, botulinum toxin A induces caspase-3 and -7 dependent apoptotic processes in the T47D breast cancer cell line.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.3 no.2
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• pp.103-112
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• 2017

The combination of nanoparticle with radioisotope could give the in vivo information with high sensitivity and specificity. However, radioisotope labeling of nanoparticle is very difficult and radioisotopes have different physicochemical properties, so the radioisotope selection of nanoparticle should be carefully considered. $^{18}F$ was first option to be considered for labeling of nanoparticle. For the labeling of $^{18}F$ with nanoparticle, Prosthetic group is widely used. Iodine, another radioactive halogen, is often used. Since radioiodine isotopes are various, they can be used for different imaging technique or therapy in the same labeling procedures. $^{99m}Tc$ can easily be obtained as pertechnatate ($^{99m}{TcO_4}^-$) by commercial generator. Ionic $^{68}Ga$ (III) in dilute HCl solution is also obtained by generator system, but $^{68}Ga$ can be substituted for $^{67}Ga$ because of the short half-life (67.8 min). $^{64}Cu$ emits not only positron but also ${\beta}-particle$. Therefore $^{64}Cu$ can be used for imaging and therapy at the same time. These radioactive metals can be labeled with nanoparticle using the bifunctional chelator. $^{89}Zr$ has longer half-life (78.4 h) and is used for the longer imaging time. Unlike different metals, $^{89}Zr$ should use the other chelate such as DFO, 3,4,3-(LI-1,2-HOPO) or DFOB.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.6
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• pp.322-326
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• 2006

A low iodine diet (LID) for $1{\sim}2$ weeks is recommended for patients who undergoing radioiodine remnant ablation. However, the LID educations for patients are different among centers because there is no concrete recommendation for protocol of LID. In this investigation, we compared two representative types of LID protocols performed in several centers in Korea using urine iodine to creatinine ratio (urine I/Cr). Methods: From 2006, April to June, patients referred to our center for radioiodine remnant ablation of thyroid cancer from several local hospitals which had different LID protocols were included. We divided into two groups, stringent LID for 1week and less stringent LID for 2 weeks, then measured their urine I/Cr ratio with spot urine when patients were admitted to the hospital. Results: Total 27 patients were included in this investigation (M:F=1:26; 13 in one-week stringent LID; 14 in two-week less stringent LID. Average of urine I/Cr ratio was $127.87{\pm}78.52{\mu}g/g$ in stringent LID for 1 week, and $289.75{\pm}188.24{\mu}g/g$ in less stringent LID for 2 weeks. It was significantly lower in stringent LID for 1 week group (p=0.008). The number of patients whose urine I/Cr ratios were below $100{\mu}g/g$ was 6 of 13 in stringent LID for 1 week group, and 3 of 14 in less stringent LID for 2 weeks group. Conclusion: Stringent LID for 1 week resulted in better urinary I/Cr ratio in our investigation compared with the other protocol. However it still resulted in plenty of inadequate range of I/Cr ratio, so more stringent protocol such as stringent LID for 2 weeks is expected more desirable.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.105-111
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• 1995

The relationship betwwen the molecular structure of amylopectin and the texture of cooked rice was investigated using Korean rice [3 varieties of Japonica type and 3 varieties of Tongil type(Japonica-Indica breeding type)]. The molecular structure of rice amylopectin was polymodal and distributed A chain of $\overline{DP}$ 12.4, short B chain of $\overline{DP}$ 20.6, B chain of $\overline{DP}$ 26.3, long B chain of $\overline{DP}$ 45 and super long chain of above $\overline{DP}$ 55. The super long chain of amylopectin was composed of long linear chain with poorly branched chain. Also, the super long chain of amylopectin showed positive correlated with average chain length, inherent viscosity and ${\beta}-amyloysis$ limit$({\%})$, but negative correlated with ${\lambda}max$ of iodine reaction of amylopectin. The structural properties of amylopectin in Japonica type were different from those of amylopectin in Tongil type. In relationship between molecular structure of amylopectin and texture of cooked rice, the average chain length, inherent viscosity, ${\beta}-amyloysis$ limit and super long chain of amylopectin was showed a positive correlation with hardness, but a negative correlation with adhesiveness of cooked rice. The long chain of rice amylopectin is the less, the eating quality of cooled rice was the better. These results suggest that the molecular structure of rice amylopectin could be responsible for the texture of cooked rice.