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Determination of oestrone, $17{\alpha}$-and $17{\beta}$-oestradiol in bovine aqueous humor using gas chromatography-negative ion chemical ionization mass spectrometry

  • Zafar-Iqbal;Midgley, John-M;Watson, David-G
    • Archives of Pharmacal Research
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    • v.20 no.3
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    • pp.247-252
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    • 1997
  • Perfluorotolyl (PFT)-ether and perfluorotoly-trimethylsilyl (PFT-TMS) ether derivatives of oestrone, $17{\alpha}$- and $17{\beta}$oestradiol were prepared under phase transfer conditons. The former derivatives under negative ion chemical ionization conditions gave significant ions in the mass spectrometer but $17{\alpha}$- and $17{\beta}$ -oestradiol gave poor resolution. However, the PFT-TMS derivatives of 17.${\alpha}$- and$17{\beta}$-oestradiol showed good resolution. These derivatives were used for the analysis of oestrogens in bovine aqueous humour, vitreous humour and retina. The mean $({\pm}SEM)$ concentrations of oestrone in bovine aqueous humour (n=18), vitreous humour (n=18) and bovine retina (n=4) were $0.47{\pm}0.11$, $0.46{\pm}0.14$ and $1.10{\pm}0.24 ng.ml^{-1}$, respectively. $17{\alpha}$-Oestradiol was detected in 16 out of 18 samples of bovine aqueous humour and vitreous humour and the mean $({\pm}SEM)$ concentrations were $0.30{\pm}0.10$ and $0.08{\pm}0.02 ng.ml^{-1}$, respectively. The mean $({\pm}SEM)$ concentration of 17.betha.-oestradiol in aqueous humour (n=7) and vitreous homour (n=11) $0.83{\pm}0.26 ng ml^{-1}$ and $0.39{\pm}0.09 ng ml^-1$, respectively. In retina the concentrations of both steroids were below the detection limit.

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Detection of N-Acetyltranylcypromine and Glucuronide of Phenyl-Hydroxylated N-Acetyltranlcypromine from Tranylcypromine-Dosed Rat Urine : Pharmacological Implications

  • Kang, Gun-Il;Choi, Hee-Kyung
    • Archives of Pharmacal Research
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    • v.9 no.2
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    • pp.99-110
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    • 1986
  • In order to use for metabolic studies of tranylcypromine (TCP), TCP-phenyl-$d_{5}$ was synthesized via the intermediates, 3-benzoylpropionic acid-$d_{5}$ and trans-2-phenylcyclopropanecarboxylic acid-$d_{5}$ -TCP(0.22 mmole/kg) and its deuterated analog were administered s. c. to the rats and GC/MS analyses of the urines led to the detection of N-acetyltranylcypromine (ATCP) and glucuronide conjugate of phenyl-hydroxylated ATCP. MAO activities in rat brain were measured using serotonin as the substrate. In vitro $IC_{50}$ of ATCP was determined to be $10^{-3}M$. The inhibitions by ATCP were not dependent on the preincubation time and were reversed by washing sedimented mitochondrial pellets after the preincubation. In vivo MAO inhibitions at various times of 0.5, 1.5, 3, 6, 12, and 23 hr after the administration of 0.4 mmole/kg (i. p. ) of ATCP were found to be 0.13, 73, 90, 89, and 74 %, respectively. Similarly, the inhibition percents by 0.015 mmole/kg (i. p. ) of TCP were 94, 99, 95, 91, 71 and 49%. The results strongly suggest that deacetylated product of ATCP may account for its in vivo MAO inhibition. The relationship between the metabolism via phenyl-hydroxylation and the in vivo potency of TCP was examined by QSAR study and it was found that groupings discriminating between the compounds with p-substituents and those without them only ensure high correlations, suggesting that ring-hydroxylation which occurs at the para position in most of the compounds is a determining factor to the potency of TCP.

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Determining Potential Link between Environmental and Clinical Isolates of Cryptococcus neoformans/Cryptococcus gattii Species Complexes Using Phenotypic and Genotypic Characterisation

  • Kenosi Kebabonye;Mosimanegape Jongman;Daniel Loeto;Sikhulile Moyo;Wonderful Choga;Ishmael Kasvosve
    • Mycobiology
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    • v.51 no.6
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    • pp.452-462
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    • 2023
  • Opportunistic infections due to Cryptococcus neoformans and C. gattii species complexes continue to rise unabated among HIV/AIDS patients, despite improved antifungal therapies. Here, we collected a total of 20 environmental and 25 presumptive clinical cryptococcal isolates from cerebrospinal fluid (CSF) samples of 175 patients enrolled in an ongoing clinical trial Ambition 1 Project (Botswana-Harvard Partnership). Identity confirmation of the isolates was done using MALDI-TOF MS and PCR. We describe the diversity of the isolates by PCR fingerprinting and sequencing (Oxford Nanopore Technology) of the intergenic spacer region. Mating types of the isolates were determined by amplification of the MAT locus. We report an unusual prevalence of 42.1% of C. neoformans × C. deneoformans hybrids Serotype AD (n = 16), followed by 39.5% of C. neoformans Serotype A (n = 15), 5.3% of C. deneoformans, Serotype D (n = 2), 7.9% of C. gattii (n = 3), and 5.3% of C. tetragattii (n = 2) in 38 representative isolates that have been characterized. Mating type-specific PCR performed on 38 representative environmental and clinical isolates revealed that 16 (42.1%) were MATa/MAT𝛼 hybrids, 17 (44.7%) were MAT𝛼, and five (13.2%) possessed MATa mating type. We used conventional and NGS platforms to demonstrate a potential link between environmental and clinical isolates and lay a foundation to further describe mating patterns/history in Botswana.

Xiang Study: an association of breastmilk composition with maternal body mass index and infant growth during the first 3 month of life

  • Peng, Xuyi;Li, Jie;Yan, Shuyuan;Chen, Juchun;Lane, Jonathan;Malard, Patrice;Liu, Feitong
    • Nutrition Research and Practice
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    • v.15 no.3
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    • pp.367-381
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    • 2021
  • BACKGROUND/OBJECTIVES: This study aimed to establish a mother and child cohort in the Chinese population, and investigate human breastmilk (HBM) composition and its relationship with maternal body mass index (BMI) and infant growth during the first 3 mon of life. SUBJECTS/METHODS: A total of 101 Chinese mother and infant pairs were included in this prospective cohort. Alterations in the milk macronutrients of Chinese mothers at 1 mon (T1), 2 mon (T2), and 3 mon (T3) lactation were analyzed. HBM fatty acid (FA) profiles were measured by gas chromatography (GC), and HBM proteomic profiling was achieved by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). RESULTS: During the first 3 mon of lactation (P < 0.05), significant decreases were determined in the levels of total energy, fat, protein, and osteopontin (OPN), as well as ratios of long-chain saturated FA (including C16:0, C22:0 and C24:0), monounsaturated FA (including C16:1), and n-6 poly unsaturated FA (PUFA) (including C20:3n-6 and C20:4n-6, and n-6/n-3). Conversely, butyrate, C6:0 and n-3 PUFA C18:3n-3 (α-linolenic acid, ALA) were significantly increased during the first 3 mon (P < 0.05). HBM proteomic analyses distinguished compositional protein differences over time (P = 0.001). Personalized motherinfant analyses demonstrated that HBM from high BMI mothers presented increased total energy, fat, protein and OPN, and increased content of n-6 PUFA (including C18:3n-6, C20:3n-6 and n-6/n-3 ratio) as compared with low BMI mothers (P < 0.05). Furthermore, BMI of the mothers positively correlated with the head circumference (HC) of infants as well as the specific n-6 PUFA C20:3n-6 over the 3 time points examined. Infant HC was negatively associated with C18:0. CONCLUSION: This study provides additional evidence to the Chinese HBM database, and further knowledge of FA function. It also helps to establish future maternal strategies that support the healthy growth and development of Chinese infants.

Properties of AlN epilayer grown on 6H-SiC substrate by mixed-source HVPE method (6H-SiC 기판 위에 혼합소스 HVPE 방법으로 성장된 AlN 에피층 특성)

  • Park, Jung Hyun;Kim, Kyoung Hwa;Jeon, Injun;Ahn, Hyung Soo;Yang, Min;Yi, Sam Nyung;Cho, Chae Ryong;Kim, Suck-Whan
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.30 no.3
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    • pp.96-102
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    • 2020
  • In this paper, AlN epilayers on 6H-SiC (0001) substrate are grown by mixed source hydride vapor phase epitaxy (MS-HVPE). AlN epilayer of 0.5 ㎛ thickness was obtained with a growth rate of 5 nm per hour. The surface of AlN epilayer grown on 6H-SiC (0001) substrate was investigated by field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectroscopy (EDS). Dislocation density was considered through HR-XRD and related calculations. A fine crystalline AlN epilayer with screw dislocation density of 1.4 × 109 cm-2 and edge dislocation density of 3.8 × 109 cm-2 was confirmed. The AlN epilayer on 6H-SiC (0001) substrate grown by using the mixed source HVPE method could be applied to power devices.

Effects of CaCO3 on the Defects and Grain Boundary Properties of ZnO-Co3O4-Cr2O3-La2O3 Ceramics (ZnO-Co3O4-Cr2O3-La2O3 세라믹스의 결함과 입계 특성에 미치는 CaCO3의 영향)

  • Hong, Youn-Woo;Ha, Man-Jin;Paik, Jong-Hoo;Cho, Jeong-Ho;Jeong, Young-Hun;Yun, Ji-Sun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.31 no.5
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    • pp.307-312
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    • 2018
  • Liquid phases in ZnO varistors cause more complex phase development and microstructure, which makes the control of electrical properties and reliability more difficult. Therefore, we have investigated 2 mol% $CaCO_3$ doped $ZnO-Co_3O_4-Cr_2O_3-La_2O_3$ (ZCCLCa) bulk ceramics as one of the compositions without liquid phase sintering additive. The results were as follows: when $CaCO_3$ is added to ZCCLCa ($644{\Omega}cm$) acting as a simple ohmic resistor, CaO does not form a secondary phase with ZnO but is mostly distributed in the grain boundary and has excellent varistor characteristics (high nonlinear coefficient ${\alpha}=78$, low leakage current of $0.06{\mu}A/cm^2$, and high insulation resistance of $1{\times}10^{11}{\Omega}cm$). The main defects $Zn_i^{{\cdot}{\cdot}}$ (AS: 0.16 eV, IS & MS: 0.20 eV) and $V_o^{\bullet}$ (AS: 0.29 eV, IS & MS: 0.37 eV) were found, and the grain boundaries had 1.1 eV with electrically single grain boundary. The resistance of each defect and grain boundary decreases exponentially with increasing the measurement temperature. However, the capacitance (0.2 nF) of the grain boundary was ~1/10 lower than that of the two defects (~3.8 nF, ~2.2 nF) and showed a tendency to decrease as the measurement temperature increased. Therefore, ZCCLCa varistors have high sintering temperature of $1,200^{\circ}C$ due to lack of liquid phase additives, but excellent varistor characteristics are exhibited, which means ZCCLCa is a good candidate for realizing chip type or disc type commercial varistor products with excellent performance.

Isolation and Identification of Antioxidant Compound from the Lythrum Salicaria L. Roots (털부처꽃(Lythrum Salicaria L.) 뿌리로부터 항산화 물질의 분리 및 구조동정)

  • Lee, Kyeong-Hee;Lee, Dae-Young;Lee, Seung-Eun;Noh, Hyung-Jun;Lee, Jeong-Hoon;Choi, Jehun;Park, Chun-Geun;Kim, Seung-Yu;Lee, Jun-Su;Kim, Geum-Soog
    • Journal of Applied Biological Chemistry
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    • v.57 no.4
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    • pp.359-363
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    • 2014
  • The roots of Lythrum salicaria L. were extracted in 80% aqueous MeOH and the concentrated extract was fractionated with EtOAc, n-BuOH, and $H_2O$, successively. The repeated silicagel and octadecyl $SiO_2$ column chromatographies of the EtOAc fractions led to isolation of an antioxidant compound and two major compounds. From the results of spectral data and the chemical characteristics including nuclear magnetic resonance, MS, and IR, the structures of compounds were determind as myricetin-3-O-${\beta}$-D-glucopyranoside (1), oleanolic acid (2), betulinic acid (3). This is the first reported isolation of compounds (1, 2) from L. salicaria. Compound 1 as well as EtOAc, n-BuOH, and $H_2O$ solvent fractions were evaluated for 2,2-dipicryl-1-phenylhydrazyl radical scavenging activity.

Analysis of Styrene Dimer and Trimer in Cup Noodle Containers (컵라면 용기중의 스티렌다이머와 트리머의 분석)

  • Lee, Kwang-Ho;Jang, Young-Mi;Kwak, In-Shin;Yoo, Seung-Seok;Kim, Ki-Myeong;Choi, Byung-Hee;Lee, Chul-Won
    • Korean Journal of Food Science and Technology
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    • v.31 no.4
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    • pp.931-937
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    • 1999
  • Styrene dimers and trimers from polystyrene cup noodle containers were analyzed by GC and GC/MS extracted with various simulants. For the quantitation of styrene dimers and trimers, 1,3-diphenylpropane (DP) and benzyln-butyl phthalate (BBP) were chosen as the standards. The results showed that the average of the styrene dimers in the containers was 603 ppm, and that of trimers was 5731 ppm. Four styrene dimers, including 1,2-diphenyl-cyclobutane, were identified as well as seven trimers such as 2,4,6-triphenyl-l-hexene. The migration of the styrene dimers and trimers, from the cup noodle containers of polystyrene into foods, was conducted using simulants including boiling water as well as soybean oil and n-heptane. In addition to, the analysis of each migrated styrene was also performed filled with boiling water into noodle and soup after certain time (5, 10, 20, 30 min). The results showed that the migration of styrene dimers and trimers from cup noodle containers was not detected in the case of using boiled water or soybean oil as a simulant, while styrene dimers and trimers were detected 1.18 ppm and 14.21 ppm, respectively, when heptane was adopted as a simulant. In the case of filling with boiled water into noodle and soup, both styrenes were not detected at 5 min and 10 min, however, some samples standing for 20 min released styrene dimers and trimers as much as 0.009 ppm, and 0.019 ppm for 30 min.

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Antioxidant Activity of the Extractives from the Needles of Picea abies Karsten (독일가문비(Picea abies Karsten) 잎 추출성분의 항산화 활성)

  • Lee, Sang-Keug;Bae, Young-Soo
    • Journal of Korean Society of Forest Science
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    • v.95 no.4
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    • pp.429-434
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    • 2006
  • The dried needles (1.5 kg) of Picea abies Karsten were ground, extracted with acetone-$H_2O$ (7:3, v/v), concentrated, and fractionated with a series of n-hexane, methylene chloride, ethyl acetate and water on a separatory funnel. Each fraction was freeze dried, then a portion of ethyl acetate soluble powder was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-n-hexane mixture as eluents. The isolated compounds were identified by cellulose TLC, $^1H$-, $^{13}C$-NMR, FAB and EI-MS. (+)-catechin (compound I), (-)-epicatechin (compound II), kaempferol-3-O-${\beta}$-D-glucopyranoside (compound III), 4-hydroxyacetophenone (compound IV) were isolated from the ethyl acetate soluble fraction and (+)-catechin (compound I), protocatechuic acid (compound V) were isolated from the $H_2O$ soluble fraction of P. abies needle. The antioxidative activities of each fraction and the isolated compounds were tested by DPPH radical scavenging method, and EtOAc soluble fraction, (+)-catechin and (-)-epicatechin showed similar values to ${\alpha}$-tocopherol and BHT as controls.

Metabolic Changes in Patients with Parkinson's Disease after Stereotactic Neurosurgery by Follow-up 1H MR Spectroscopy

  • Choe, Bo-Young;Baik, Hyun-Man;Chun, Shin-Soo;Son, Byung-Chul;Kim, Moon-Chan;Kim, Bum-Soo;Lee, Hyoung-Koo;Suh, Tae-Suk
    • Journal of the Korean Magnetic Resonance Society
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    • v.5 no.2
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    • pp.99-109
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    • 2001
  • Authors investigated neuronal changes of local cellular metabolism in the cerebral lesions of Parkinsonian symptomatic side between before and after stereotactic neurosurgery by follow-up 1H magnetic resonance spectroscopy (MRS). Patients with Parkinson's disease (PD) (n = 15) and age-matched normal controls (n = 15) underwen MRS examinations using a stimulated echo acquisition mode (STEAM) pulse sequence that provided 2${\times}$2${\times}$2 ㎤ (8ml) volume of interest in the regions of substantia nigra, thalamus, and lentiform nucleus. Spectral parameters were 20 ms TE, 2000 ms TR, 128 averages,2500 Hz spectral width, and 2048 data points. Raw data were processed by the SAGE data analysis package (GE Medical Systems). Peak areas of N-acetylaspartate (NAA), creatine (Cr), choline-containing compounds (Cho), inositols (Ins), and the sum (Glx) of glutamate and GABA were calculated by means of fitting the spectrum to a summation of Lorentzian curves using Marquardt algorithm. After blindly processed, we evaluated neuronal alterations of observable metabolite ratios between before and after stereotactic neurosurgery using Pearson product-moment analysis (SPSS, Ver. 6.0). A significant reduction of NAA/Cho ratio was observed in the cerebral lesion in substantia nigra of PD patient related to the symptomatic side after neurosurgery (P : 0.03). In thalamus, NAA/Cho ratio was also significantly decreased in the cerebral lesion including the electrode-surgical region (P : 0.03). A significant reduction of NAA/Cho ratio in lentiform nucleus was not oberved, but tended toward significant reduction after neurosurgery (P = 0.08). In particular, remarkable lactate signal was noted from the surgical thalamic lesions of 6 among 8 patients and internal segments of globus pallidus of 6 among 7 patients, respectively. Significant metabolic alterations of NAA/Cho ratio might reflect functional changes of neuropathological processes in the lesion of substantia nigra, thalamus, and lentiform nucleus, and could be a valuable finding fur evaluation of Parkinson's disease after neurosurgery. Increase of lactate signals, being remarkable in surgical lesions, could be consistent with a common consequence of neurosurgical necrosis. Thus, IH MRS could be a useful modality to evaluate the diagnostic and prognostic implications fur Parkinsons disease after functional neurosurgery.

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