• Title/Summary/Keyword: BR2K

Search Result 1,061, Processing Time 0.032 seconds

Kinetic Studies on Halogen Exchange of Substituted Benzenesulfonylbromides

  • Kim, Jaerok
    • Nuclear Engineering and Technology
    • /
    • v.5 no.4
    • /
    • pp.321-333
    • /
    • 1973
  • The rates and activation parameters for the halide exchange reactions of substituted benzenesulfonylbromides (R-C$_{6}$H$_4$SO$_2$Br, R=p-MeO, p-$CH_3$, p-H, p-NO$_2$) in dry acetone at two temperatures were determined. It was found that the nucleophilicity order of Cl->I-$\geq$Br- for strong electron withdrawing-, and mild electron donating group, and of I-$\geq$Cl->Br- for strong electron donating group, Hammett plots showed slightly convoked characteristics which is similar to the plots of substituted benzenesulfonylchlorides, but contrary to the concaved nature for the halide exchange reactions of substituted benzyl chlorides. The rate of halogen exchange between benzenesulfonylbromide and lithium bromide decreased in the order of solvent : ($CH_3$)$_2$CO>$CH_3$CN》MeOH. The rates and activation parameters were also compared with those already known in the substituted benzenesulfonylchlorides. Theses were explained in terms of the structural properties of the transition state, and discussed the reaction mechanisms.s.

  • PDF

Expression of BrD1, a Plant Defensin from Brassica rapa, Confers Resistance against Brown Planthopper (Nilaparvata lugens) in Transgenic Rices

  • Choi, Man-Soo;Kim, Yul-Ho;Park, Hyang-Mi;Seo, Bo-Yoon;Jung, Jin-Kyo;Kim, Sun-Tae;Kim, Min-Chul;Shin, Dong-Bum;Yun, Hong-Tai;Choi, Im-Soo;Kim, Chung-Kon;Lee, Jang-Yong
    • Molecules and Cells
    • /
    • v.28 no.2
    • /
    • pp.131-137
    • /
    • 2009
  • Plant defensins are small (5-10 kDa) basic peptides thought to be an important component of the defense pathway against fungal and/or bacterial pathogens. To understand the role of plant defensins in protecting plants against the brown planthopper, a type of insect herbivore, we isolated the Brassica rapa Defensin 1 (BrD1) gene and introduced it into rice (Oryza sativa L.) to produce stable transgenic plants. The BrD1 protein is homologous to other plant defensins and contains both an N-terminal endoplasmic reticulum signal sequence and a defensin domain, which are highly conserved in all plant defensins. Based on a phylogenetic analysis of the defensin domain of various plant defensins, we established that BrD1 belongs to a distinct subgroup of plant defensins. Relative to the wild type, transgenic rices expressing BrD1 exhibit strong resistance to brown planthopper nymphs and female adults. These results suggest that BrD1 exhibits insecticidal activity, and might be useful for developing cereal crop plants resistant to sap-sucking insects, such as the brown planthopper.

Changes in Visual Acuity and Values of Objective Refraction with Breath Alcohol Concentration (호흡 알코올 농도에 따른 시력과 타각적 굴절검사 값의 변화)

  • Jung, Su A;Nam, Soo-Kyung;Kim, Hyun Jung
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.20 no.2
    • /
    • pp.187-193
    • /
    • 2015
  • Purpose: This study was aimed to investigate effects of increased breath alcohol concentration (BrAC) which is the standard measurement of alcohol consumption in sobriety test under current laws on visual acuity and values of objective refraction. Methods: For twenty three males in 20s (average age $21.17{\pm}2.19$ years, body mass index (BMI) $22.09{\pm}2.16$) were selected. Distance and near visual test was performed at BrAC of 0%, 0.05% and 0.08%, and objective refraction with open-field auto-refractometer was also performed at different BrAC. Results: As breath alcohol concentration is increased, distance visual acuity was decreased, which was statistically significant, but near visual acuity was not changed. Also, values of objective refraction tended to be increased towards minus as breath alcohol concentration is increased. Conclusions: As breath alcohol concentration is increased, corrected visual acuity is decreased and refractive power is towards minus, it is necessary that visual acuity test and refraction measurement should be conducted under sober condition.

Effects of Gamma Irradiation and Methyl Bromide Fumigation on Quarantine Pest and Physical Quality of Apples (감마선과 methyl bromide 처리가 사과의 검역해충 및 물리적 품질에 미치는 영향)

  • Kang, Ho-Jin;Kwon, Yong-Jung;Byun, Myung-Woo;Kim, Hyun-Ku;Chung, Hun-Sik;Choi, Jong-Uook;Kwon, Joong-Ho
    • Korean Journal of Food Science and Technology
    • /
    • v.35 no.5
    • /
    • pp.783-790
    • /
    • 2003
  • Tetranychus urticae Koch and Panonychus ulmi Koch were identified as quarantine pests in apple samples and were controlled soon after the commercial treatment of methyl bromide (MeBr) and with irradiation doses $(0.5{\sim}3kGy)$ after irradiation. The physical qualities of apples, such as rotting, withering, weight changes, hardness, and color, were apparently affected by MeBr. Furthermore, more than 2 kGy irradiation resulted from the lapse of storage time. Associated with the physical qualities of stored apples, irradiation and fumigation for quarantine purposes were more adequate after 40 days of storage at $0{\pm}1^{\circ}C\;(85{\pm}2%\;RH)$ immediately following harvest, rather than soon after harvest. Less than 1 kGy irradiation, based on its accumulated control effect on pests, can potentially be applied as a quarantine procedure without causing significant changes in the physical qualities of fresh apples, in contrast to MeBr.

Cloning and Expression of the Bacillus thruingiensis var. kurstaki HD-1 Crystal Protein gene in Eschelichia coli

  • Sang Hyn Kim;You
    • Journal of Sericultural and Entomological Science
    • /
    • v.35 no.2
    • /
    • pp.129-133
    • /
    • 1993
  • The 44Md plasmid of Bacillus thruingiensis var. kurstaki HD-1(B. t k HD-1) was partially digested with Sau3AI and the fragments were cloned into E. coli HB101 on vector pBR322. Of 2, 950 clones with a recombinant pBR322, only one clone KC1 was determined to have the gene for crystal toxic proteins from the 44Md plasmid of B. t k HD-1 at the BamHI site of pBR322. The recombinant pBR322 was named pKC1 and its molecular size was 12kb. The KC1 produced a protein which was toxic to the silkworm and antigenically similar to the crystal toxic protein of B. t k HD-1. Also, electrophoretic mobility of the KC1 protein was apparently the same as that of the crystal toxic protein of B. t k HD-1.

  • PDF

Isolation and functional characterization of BrUGT gene encoding a UDP-glycosyltransferase from Chinese cabbage (Brassica rapa)

  • Jung, Yu-Jin;Lee, Hye-Jung;Choi, Jang-Sun;Cho, Yong-Gu;Nou, Ill-Sup;Kang, Kwon-Kyoo
    • Journal of Plant Biotechnology
    • /
    • v.39 no.3
    • /
    • pp.212-218
    • /
    • 2012
  • Glycosyltransferases are enzymes (EC 2.4) that catalyze the transfer of monosaccharide moieties from activated nucleotide sugar to a glycosyl acceptor molecule which can be a carbohydrate, glycoside, oligosaccharide, or a polysaccharide. In this study, a UDP-glucosyltransferase cDNA was isolated from Brassica rapa using a rapid amplification of cDNA ends (RACE) and subsequently named BrUGT. It has a full-length cDNA of 1,236 bp with 119 bp 5'-untranslated region (UTR), a complete ORF of 834 bp encoding a polypeptide of 277 amino acids (31.19 kDa) and a 3'-UTR of 283 bp. BLASTX analysis hits a catalytic domain of Glycos_transf_1 super family (cl12012) that belongs to the Glycosyltransferases group 1 with tetratricopeptide (TPR) regions located between 165 to 350 bp. Expression analysis showed high mRNA transcripts in pistil, followed by petal, seed and calyx of flower. Moreover, expression analysis of BrUGT in Chinese cabbage seedlings under stresses of cold, salt, PEG, $H_2O_2$, drought and ABA showed elevated mRNA transcript. Furthermore, when BrUGT gene was transformed into rice using pUbi-1 promoter, overexpression was evident among the $T_1$ plants. This study provides insights into the function of BrUGT in plants.

Aroma Analysis by the Electronic Nose on Red Ginseng Powder Treated with Gamma Radiation, Methyl Bromide and Phosphine (전자코를 이용한 감마선, methyl bromide 및 phosphine 처리된 홍삼분말의 저장 중 향기패턴 변화 연구)

  • Shin, Jung-Ah;Kwon, Joong-Ho;Lee, Ki-Teak
    • Korean Journal of Food Science and Technology
    • /
    • v.35 no.5
    • /
    • pp.825-829
    • /
    • 2003
  • An electronic nose was applied to analyze the aroma patterns of powdered red ginseng that had been treated with different preservative methods, such as gamma radiation at 5kGy, commercial methyl bromide (MeBr) and phosphine fumigations. Aroma patterns of phosphine or MeBr, fumigated samples were well separated according to storage temperature and period. However, 5kGy-irradiated samples (stored for 1 and 2 months) were hardly discriminated by the different storage temperatures ($25^{\circ}C$ and $-10^{\circ}C$). After 5 months at $-10^{\circ}C$, non-treated and phosphine fumigated samples showed similar aroma patterns.

Inhibitory Effects of 3-Bromopyruvate on Human Gastric Cancer Implant Tumors in Nude Mice

  • Xian, Shu-Lin;Cao, Wei;Zhang, Xiao-Dong;Lu, Yun-Fei
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.7
    • /
    • pp.3175-3178
    • /
    • 2014
  • Background: Gastric cancer is a common malignant tumor. Our previous study demonstrated inhibitory effects of 3-bromopyruvate (3-BrPA) on pleural mesothelioma. Moreover, we found that 3-BrPA could inhibit human gastric cancer cell line SGC-7901 proliferation in vitro, but whether similar effects might be exerted in vivo have remained unclear. Aim: To investigate the effect of 3-BrPA to human gastric cancer implant tumors in nude mice. Materials and Methods: Animals were randomly divided into 6 groups: 3-BrPA low, medium and high dose groups, PBS negative control group 1 (PH7.4), control group 2 (PH 6.8-7.8) and positive control group receiving 5-FU. The TUNEL method was used to detect apoptosis, and cell morphology and structural changes of tumor tissue were observed under transmission electron microscopy (TEM). Results: 3-BrPA low, medium, high dose group, and 5-FU group, the tumor volume inhibition rates were 34.5%, 40.2%, 45.1%, 47.3%, tumor volume of experimental group compared with 2 PBS groups (p<0.05), with no significant difference between the high dose and 5-FU groups (p>0.05). TEM showed typical characteristics of apoptosis. TUNEL demonstrated apoptosis indices of 28.7%, 39.7%, 48.7% for the 3-BrPA low, medium, high dose groups, 42.2% for the 5-FU group and 5% and 4.3% for the PBS1 (PH7.4) and PBS2 (PH6.8-7.8) groups. Compared each experimental group with 2 negative control groups, there was significant difference (p<0.05); there was no significant difference between 5-FU group and medium dose group (p>0.05), but there was between the 5-FU and high dose groups (p<0.05). Conclusions: This study indicated that 3-BrPA in vivo has strong inhibitory effects on human gastric cancer implant tumors in nude mice.

Analysis of Selenium in Grain with ORC Collision-Removal of Br Interference using Mathematical Calibration (ORC ICPMS에서의 곡류중의 셀레늄 분석-수학적 보정을 이용한 Br의 간섭제거)

  • Cho, Heon-Hong;Pak, Yong-Nam
    • Journal of the Korean Chemical Society
    • /
    • v.55 no.3
    • /
    • pp.472-477
    • /
    • 2011
  • The concentration of selenium in grain samples was determined using isotope dilution method in ORC-ICPMS. The experimental conditions were optimized to $H_2$ mode and the flow rate was $4.0\;mL\;min^{-1}$. ORC in $H_2$ mode proved to eliminate most of polyatomic interferences except $BrH^+$ when Br is present in sample matrix. Chemical removal of Br was very difficult and the mathematical correction was successfully employed. The fraction of $BrH^+$ generated from Br at the current experimental condition was 14.1%. The signal on m/z 82 was corrected and calculated for isotope dilution. The analytical reliability of the propose method was successfully evaluated by analyzing the certified standard reference material NIST SRM 1566 and 1567. The method was applied to real samples and the results are $0.034{\pm}0.001\;{\mu}g\;g^{-1}$ for white rice, $0.059{\pm}0.002_5\;{\mu}g\;g^{-1}$ for brown rice, $0.029{\pm}0.001_4\;{\mu}g\;g^{-1}$ for black rice, and $0.034{\pm}0.002\;{\mu}g \;g^{-1}$ for barley. The detection limits ($3\sigma$) for Se was $0.012\;ng\;g^{-1}$.

FIXED/REMOVABLE RECONSTRUCTION IN PARTIALLY EDENTULOUS PATIENT USING $Br{\aa}nrmark$ OSSEOINTEGRATED IMPLANTS AND TWO-PART I.T.I. IMPLANTS(BONEFIT) AS ABUTMENTS (Free-Standing $Br{\aa}nrmark$ Osseointegrated Implants와 Two-part I.T.I. Dental Implants(Benefit)를 이용한 하악 양측 대구치 결손 수복에 관한 임상적 연구(I))

  • Yang, Jae-Ho
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.31 no.1
    • /
    • pp.151-162
    • /
    • 1993
  • The author installed $3.75mm\times10mm$ $Br{\aa}nrmark$ osseointegrated implants and $3.5mm\times8mm$ I.T.I. hollow screw implants(Benefit) as a free standing abutment to replace lower left and right molars of 44-year-old female patient. Form the foregoing procedure, the author obtained the following results. 1. Free-standing $Br{\aa}nrmark$ and I.T.I. Hollow screw implants(Benefit) could be used to replace molars effectively without reduction of adjacent natural teeth, 2. Rotation of occlusal gold screw of $Br{\aa}nrmark$ implants was observed under occlusal force. 3. Adjustment of height of I.T.I. abutments was necessary in the mandibular second molar because of the limited occlusal clearance. 4. Form the oral examination, patient comments, panoramic and periapical radiographs, there were no pain, gingival imflammation and mobility, but slight reduction of alveolar bone level was shown around both implant systems. 5. Patient comments were comfortable on both systems. but the patient complained about economic problem of $Br{\aa}nrmark$ system and long treatment treatment time of both systems.

  • PDF