• Korean Journal of Microbiology
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• v.23 no.3
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• pp.203-208
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• 1985

Partial characterization of B. thuringiensis var. kurstaki 3ab temperature-sensitive mutants was carried out through biochemical analyses, utilization tests of carbohydrate sources, antobiotic resistant test, hemolytic reaction test, growth measurement of Fructus gardenia sxtrant medium and toxicity test against mice. Six ts mutants, ts-U154, ts-U601, ts-U602, ts-U603, tsU-604, and ts-U788 could not produce urease, ts-U603 lost its motility, ts-U154 could not use salicin and cellobiose and ts-U603 not ribose. All ts mutants except ts-U154 and wild type strain were resistant to cephalothin, ampicillin, and penicillin. but ts-U154 was sensitive to the three. Four mutants, ts-U21, ts-U74, ts0U131 and ts-U154 did not form pigment colonies on the F. gardenia medium. All the mutants and wild type strain showed hemolysis reaction on the blood agar. The B. thuringiensis and mutants were not toxic to mice.

• Microbiology and Biotechnology Letters
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• v.11 no.3
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• pp.233-239
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• 1983

Bacillus thuringiensis was mutagenized with UV light irradiation and nitrosoguanidine. Twenty-four tem perature-sensitive ts mutants were isolated at 42$^{\circ}C$ and classified into two groups by growth on nutrient agar at 42$^{\circ}C$. First is the lethal group, which did not grow at the nonpermissive temperature, the second is the reduced group whose growth was restricted from one-half to one-fourth, Thirteen ts mutants belong to the lethal group and eleven ts mutants belong to the reduced group. Auxotrophic mutant, A-N28 required five amino acids as growth factors, A-N65 also five amino acids, A-N92 seven, A-N115 four and A-N156 three. Bacillus thuringiensis wild type is resistant to penicillin, ampicillin, and cephalothin. The ts-Ul7l, A-N92 and A-Nl15 are sensitive to the three antibiotics. The ts -U601, -U603, -U604 and -Ul71 did not grow at the permissive temperature after temperature-shifting from 42$^{\circ}C$. Four auxotrophic mutants (A-N38, A-N65, A-N92 and A-Nl15) did not form spores in their cells.

• Bulletin of the Korean Chemical Society
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• v.17 no.9
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• pp.849-853
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• 1996

Hetero Dieis-Alder reactions containing phosphorus atom at various positions of diene and dienophile as well as standard Dieis-Alder reaction between ethylene and cis-l,3-butadiene have been studied using ab initio method. Activation energy showed a good linear relationship with the FMO energy gap between diene and dienophile, which can be normally used to explain Dieis-Alder reactivity. Since π-bond cleavage and σ-bonds formation occur concertedly at the TS, geometrical distortion of diene and dienophile from the reactant to the transition state is the source of barrier. Based on the linear correlations between activation barrier and deformation energy, and between deformation energy and π-bond order change, it was concluded that the activation barrier arises mainly from the breakage of π-bonds in diene and dienophile. Stabilization due to favorable orbital interaction is relatively small. The geometrical distortions raise MO levels of the TS, which is the origin of the activation energy. The lower barrier for the reactions of phosphorus containing dienophile (reactions C, D, and E) can be explained by the electronegativity effect of the phosphorus atom.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.175-180
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• 2009

Purpose: Detection of TSH-binding inhibitor immunoglobulin (TBII) in patients with hyperthyroidism is an important result of Graves' disease (GD) and hyperthyroidism treatment. This has been made out an inspection by commercial radio-receptor assays. To increase the sensitivity and the specificity of the assay, many results of the assay were reported. In this study we evaluated the clinical usetulness of TBII assays by the Comparative method. Material and Methods: We were measured by using healthy control group (n=30, male=20, female=10) of Seoul National University Hospital Healthcare System Gangnam Center from January to March in 2009. Similarly, We were measured by using hyperthyroid (TSH<$0.05\;{\mu}IU/mL$, FT4>1.80 ng/dL) experimental group (n=58, male=14, female=44) of division of endocrinology and metabolism department of internal medicine Seoul National University Hospital from January to March in 2009. We made a comparative study of each two assays from the first generation to the third generation. We were used of TSAb assay as a measurement of GD diagnostic technique. Results: The specificity of healthy control group was 100% according to the generation. (Specificity=100%, n=30) The sensitivity of hyperthyroid experimental group were the first generation RSR<%> (79.3%, n=58), RSR (51.7%, n=58), the second generation RSR-CT (93.1%, n=58), BRAHMSCT (98.3%, n=58), the third generation ELISA (94.6%, n=56), ECLIA (97.7%, n=58) and TS-Ab<%> (93.5%, n=46). Conclusion: We were used of TSAb assay as a measurement of GD diagnostic technique, The result of data showed a high correlation between the third generation TBII assay and the second generation TBII assay ($R^2$=0.923). Instead of the first generation assay, the second generation assay can be more useful in clincal diagnosis.

• Bulletin of the Korean Chemical Society
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• v.18 no.8
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• pp.880-886
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• 1997

Ab initio calculations were carried out on the gas phase acid-catalyzed hydrolysis reactions of sulfinamide using the 3-21G* basis sets. Single point calculations were also performed at the MP2/6-31G* level. The first step in the acid-catalyzed hydrolysis of N-methylmethanesulfinamide, Ⅰ, involves protonation. The most favorable form is the O-protonated one, Ⅱ, which is then transformed into a sulfurane intermediate, Ⅲ, by addition of a water molecule. The reaction proceeds further by an intramolecular proton transfer from O to N (TS2), which is followed by N-S bond cleavage (TS3) leading to the final products. The rate determining step is the N-S bond cleavage (TS3) at the RHF/3-21G* level, whereas it becomes indeterminable at the MP2/6-31G*//3-21G* level of theory. However, the substituent effect studies with N-protonated N-arylmethanesulfinamide, ⅩⅢ, at the MP2/6-31G*//3-21G* level support the N-S bond breaking step as rate limiting.

• Bulletin of the Korean Chemical Society
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• v.7 no.5
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• pp.395-399
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• 1986

Intramolecular proton transfer equilibria of acetamide and methyl carbamate have been studied theoretically by MNDO MO method. For both substrates, carbonyl-O protonated tautomer was found to be the most stable form, the next most stable one being N-protonated form. Gas phase proton transfers take place by the 1,3-proton rearrangement process and in all cases have prohibitively high activation barriers. When however one solvate water molecule participates in the process, the barriers are lowered substantially and the process proceeds in an intermolecular manner through the intermediacy of the water molecule via a triple-well type potential energy surface; three wells correspond to reactant(RC), intermediate(IC) and product complex(PC) of proton donor-acceptor pairs whereas two transition states(TS) have proton-bridge structure. General scheme of the process can be represented for a substrate with two basic centers(heteroatoms) of A and B as, $$ABH\limits^+\;+\;H_2O\;{\to}\;ABH\limits^+{\cdots}{\limits_{RC}}OH_2\;{\to}\;AB{\cdots}H\limits_{TS}^+{\cdots}{\limits_{1}}OH_2\;{\to}\;AB{\cdots}{\limits_{IC}}H\limits^+OH_2\;{\to}\;BA{\cdots}H\limits_{TS}^+{\cdots}{\limits_{2}}OH_2\;{\to}\;BA H\limits^+{\cdots}{\limits_{PC}}OH_2\;{\to}\;BAH\limits^+\;+\;H_2O$$ Involvement of a second solvate water had negligible effect on the relative stabilities of the tautomers but lowered barrier heights by 5∼6 Kcal/mol. It was calculated that the abundance of the methoxy-O protonated tautomer of the methyl carbamate will be negligible, since the tautomer is unfavorable thermodynamically as well as kinetically. Fully optimized stationary points are reported.

• Journal of Sasang Constitutional Medicine
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• v.21 no.1
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• pp.99-126
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• 2009

1. Objective TS-QSCD (The Two-Step Questionnaire for the Sasang Constitution Diagnosis) is one of the self-reporting Sasang-Constitutional diagnosis questionnaires and one constituted by a two-step discriminant function. The process of TS-QSCD is as follows. During the first step, the testers are classified into two groups: the Yangin(陽人) group and Eumin(陰人) group. Following this, the Yangin group is divided into the Soyangin group and Taeyangin group likewise the Eumin group is divided into the Taeumin group and Soeumin group. This questionnaire has the merits of an ordinary questionnaire with four discriminant functions and a decision tree method. The purpose of this study is to evaluate and standardize TS-QSCD 2. Materials and Methods TS-QSCD was administered to 352 random informants who were examined by professionals. Reliability was tested by inter-item consistency using cronbach's ${\alpha}$, and validity was tested by a two step discriminant function. Cross tabulation Analysis was also used to look into the distribution of responses among the groups. 3. Result 1) The reliability of TS-QSCD was relatively valid. The internal consistency of TS-QSCD (AB) was cronbach's ${\alpha}$= 0.815, and TS-QSCD (AC) was cronbach's ${\alpha}$= 0.832. 2) There was a significant difference in points between Eumin group teens and other age groups, between those of Soeumin teens and other age groups. 3) TS-QSCD corresponded with the real Sasang constitution at the rate of 65.0%. When using 61 questions and four discriminant function as with ordinary methods, TS-QSCD corresponded with the real Sasang constitution at the rate of 74.9%. 4. Conclusion 1) TS-QSCD that complements the merits of existing questionnaires is effective in diagnosing Sasang constitutions. 2) Deleting duplicate questions is thought to be one of the reasons for the decreased validity rate. 3) The lower the validity of the first step, the more we should build up at each second steps a way to rescue the groups which were assigned wrongly during the first steps. 4) This standardization of TS-QSCD would be helpful in making a program for diagnosing the Sasang Constitution

• Animal Bioscience
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• v.37 no.6
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• pp.1031-1040
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• 2024

Objective: This study aimed to evaluate the effect of feeding milk replacer (MR) with varying levels of lactose and the increased supply of total solids (from 750 to 960 g/d) on performance, blood metabolites, and health of Holstein male calves during the preweaning period. Methods: Forty newborn Holstein calves (10 per treatment) were blocked according to birth weight and date of birth and distributed in a randomized block design to different liquid diets: Whole milk powder (WMP) diluted to 125 g/L solids; MR with 48% lactose (48L), diluted to 125 g/L solids; MR with 53% lactose (53L), diluted to 125 g/L solids; 53L MR corrected to 160 g/L solids (16TS) by the inclusion of a solid corrector. Calves were individually housed in wood hutches, fed 6 L/d of the liquid diet, and had free water and starter concentrate access. The study lasted 56 days. Results: Liquid diet intake was higher for calves fed 16TS than for other treatments. Calves fed 16TS presented higher protein and fat intake, followed by those fed WMP and the 48L or 53L MRs. Lactose intake was higher for 16TS-fed calves, followed by 53L, 48L, and WMP-fed calves. Starter and total dry matter intake did not differ among liquid diets. The average daily gain was higher for 16TS than 48L-fed calves, with the other treatments being intermediary. The lowest feed efficiency was observed for calves fed 48L. No effects on health were observed, as well as on selected blood metabolites, except for albumin concentration, which was higher for calves fed 16TS and WMP. Conclusion: Higher total solids content (160 g/L) in MR increases nutrient intake and consequently improves the performance of dairy calves. Feeding MRs with levels of lactose up to 53% of the DM had no deleterious effect on the performance or health of the calves.

• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.337-345
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• 2002

The equilibrium structures for the ground and transition states of $C_7H_7^+$ isomers have been investigated using sophisticated ab initio quantum mechanical techniques with various basis sets. The structures of tropyrium and benzyl cations have been fully optimized at the DZP CCSD(T) levels of theory. And the structures of o-, m-and p-tolyl cations are optimized fully up to the DZ CCSD(T) levels of theory. The geometries for the transition states between three isomers of tolyl cations have been optimized up to DZP CISD level of theory. The SCF harmonic vibrational frequencies for tropylium, benzyl, and three isomers of tolyl cations are all real numbers, which confirm the potential minima and each unique imaginary vibrational frequencies for TS1 and TS2 confirm the true transition states. The relative energy of the benzyl cation with respect to the tropyrium cation is predicted to be 28.5 kJ/mol and is in good agreement with the previous theoretical predictions. The 0 K heats of formation, ${\Delta}H^{\circ}_{f0}$, have been predicted to be 890, 1095, 1101, and 1110 kJ/mol for tropylium, ortho-, meta-, and para-tolyl cations by taking the experimental value of 919 kJ/mol for the benzyl cation as the base level. The relative stability between tolyl cations is in the order of ortho

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.74-74
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• 2003

We report here the results on N-acetyl-N'-methylamide of oxazolidine (Ac-Oxa-NHMe) calculated using the ab initio molecular orbital method with the self-consistent reaction field (SCRF) theory at the HF level of theory with the 6-3l+G(d) basis set. The displacement of the $\square$-CH$_2$ group in proline ring by oxygen atom has affected the structure of proline, cis$\^$∼/ trans equilibrium, and rotational barrier. The up-puckered structure is found to be prevalent for the trans conformers of the Oxa amide. The higher cis populations of the Oxa amide can be interpreted due to the longer distance between the acetyl methyl group and the 5-methylene group of the ring for the trans conformer of the Oxa amide than that of the Pro amide. The changes in charge of the prolyl nitrogen and the decrease in electron overlap of the C$\^$∼/ N bond for TS structures seem to play a role in lowering rotational barriers of the Oxa amide compared to that of the Pro amide. The calculated preferences for cis conformers in the order of Oxa > Pro amides and for trans-to-cis rotational barriers in the order of Pro > Oxa amide in water are consistent with experimental results on Oxa-containing peptides. The pertinent distance between the prolyl nitrogen and the N$\^$∼/ H amide group to form a hydrogen bond might indicate that this intramolecular hydrogen bond could contribute in stabilizing the TS structures of Oxa and Pro amides and play a role in prolyl isomerization.