• 제목/요약/키워드: biochemical

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Tetraethylorthosilicate를 사용한 수분산 폴리우레탄/실리카 Nanocomposite의 제조 (Preparation of Waterborne Polyurethane/Silica Nanocomposites Using Tetraethylorthosilicate)

  • 신용탁;홍민기;최진주;이원기;이경배;유병원;이명구;송기창
    • Korean Chemical Engineering Research
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    • 제48권4호
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    • pp.428-433
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    • 2010
  • Isophorone diisocyanate(IPDI), poly(tetramethylene glycol)(PTMG), dimethylol propionic acid(DMPA), triethylamine(TEA), ethylenediamine(EDA), 3-aminopropyl triethoxysilane(APS)을 출발물질로 하여 수분산 폴리우레탄(Waterborne polyurethane, WPU)이 합성되었다. 이 WPU에 0~8 wt%로 첨가량이 조절된 tetraethylorthosilicate(TEOS)를 첨가한 후 Sol-Gel 반응을 진행시켜 WPU/silica nanocomposite를 제조하였다. WPU/silica nanocomposite의 평균 입경은 TEOS의 첨가량이 증가함에 따라 증가하였다. 또한 제조된 nanocomposite의 열적 안정성은 순수한 WPU보다 우수하였다.

Aminosilane Terminated 수분산 폴리우레탄 코팅 용액의 제조 및 특성 (Preparation and Properties of Aminosilane Terminated Waterborne Polyurethane)

  • 신용탁;홍민기;최진주;이원기;이경배;유병원;이명구;송기창
    • Korean Chemical Engineering Research
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    • 제48권4호
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    • pp.434-439
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    • 2010
  • Isophorone diisocyanate(IPDI), poly(tetramethyleneglycol)(PTMG), dimethylol propionic acid(DMPA)를 출발물질로 하여 NCO terminated prepolymer가 합성되었다. 이 prepolymer의 NCO기를 silane으로 capping하기 위해 0~0.02 mole로 첨가량이 조절된 aminopropyl triethoxysilane(APS)이 첨가되었다. 제조된 용액의 평균 입경은 APS의 첨가량이 증가함에 따라 증가하였다. 또한 제조된 코팅 필름의 연필 경도 및 열적안정성은 순수한 수분산 폴리우레탄보다 우수하였다.

Hematological and Serum Biochemical Analyses in Experimental Caprine Besnoitiosis

  • Nazifi, Saeed;Oryan, Ahmad;Namazi, Fatemeh
    • Parasites, Hosts and Diseases
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    • 제49권2호
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    • pp.133-138
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    • 2011
  • This study was undertaken to investigate the hematological and biochemical changes in experimentally infected goats with Besnoitia caprae from the time of infection till 360 days post-infection (PI). Six male goats were inoculated subcutaneously with $13{\times}10^7$ bradyzoites of B. caprae, and blood samples were collected from the jugular vein. The total erythrocyte and total leukocyte counts, hematocrit value, and differential leukocyte counts were determined. Serum biochemical analysis, including the total protein, albumin, total globulin, cholesterol, triglyceride, chloride, testosterone, calcium ($Ca^{2+}$), inorganic phosphorus, sodium ($Na^+$), potassium ($K^+$), iron ($Fe^{2+}$), glucose, serum amyloid A (SAA), haptoglobin (Hp), fibrinogen, ceruloplasmin, aspartate aminotransferase, alanine aminotransferase, creatine kinase, lactate dehydrogenase, and alkaline phosphatase, was undertaken. Skin biopsy from the limbs were collected at weekly intervals and histologically examined for Besnoitia cysts. Cysts were present in the skin biopsies of the leg of the infected goats from day 28 PI. There were variations in hematological analyses, but no significant difference was seen. From day 30 to 360 PI, results showed that SAA, Hp, fibrinogen, and ceruloplasmin concentrations increased, whereas testosterone concentrations decreased. Infected goats exhibited decrease of albumin and increase of serum total protein and globulin concentrations. By contrast, there were no significant differences in the remained analyses concentrations.

호흡기 증상을 나타낸 송아지 및 산양에서 분리한 pasteurella haemolytica의 생화학적 특성 및 약제감수성 (Biochemical properties and antimicrobial drug susceptibility of Pasteurella haemolytica isolated from pneumonic calves and goats)

  • 조광현;김봉환
    • 대한수의학회지
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    • 제31권4호
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    • pp.449-456
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    • 1991
  • The present study was conducted to investigate biochemical properties and antimicrobial drug susceptibilities of 57 strains of Pasteurella haemolytica (P haemolytica) isolated from pneumonic calves and goats in Youngnam province during the period from September 1989 to February 1991. P haemolytica was isolated from 95 of 142(31.7%) pneumonic calves of 1 to 6 months of age and from 9 of 24(37.5%) pneumonic goats of 2 to 10 months of age. Seasonal isolation frequency of P haemolytica in calves and goats varied from 16.6 to 35.7%, and it was higher in winter. The majority of biochemical and cultural properties of P haemolytica isolated from calves and goats were identical to those of the reference strains employed. All isolates were susceptible to ceftiofur, erythromycin, kanamycin, gentamicin, and chloramphenicol (MIC: <$25{\mu}g/ml$), some of them were resistant to amikacin, sulfadimethoxin, and streptomycin (MIC: >200IU or ${\mu}g/ml$).

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가금 유래 병원성대장균의 생화학적 성상 및 혈청형 (Biochemical properties and serotypes of pathogenic Escherichia coli isolated from poultry in Korea)

  • 성명숙;김진현;하종수;조재근;설성용;김기석
    • 대한수의학회지
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    • 제48권2호
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    • pp.145-151
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    • 2008
  • This study was conducted to investigate biochemical properties and O group serotypes of pathogenic 203 Escherichia (E.) coli isolates from poultry with collibacillosis in Korea during the period from April 2003 to December 2005. Biochemical and fermentative properties of 203 isolates of E. coli tested were in accordance with Cowan and Steel's classification standard. One hundred and forty one isolates (69.5%) could be classified into a total of 20 O serotypes. Among them, the predominant O groups were O78 (32.5%), O88 (7.8%), O15 (6.8%), O141 (6.4%), and O158 (3.0%) in decreased order. Other infrequently encountered serogroups included : O8 (2%), O161 (2%), O20 (1.5%), O125 (1.5%), O2 (1%). And O6, O18, O24, O46, O76, O109, O119, O138, O139 and O148 had a frequency of 0.5%, respectively. Sixty two isolates (30.5%) were non-typeable with standard 173 O antisera used in this study.

Characterization of Two Self-Sufficient Monooxygenases, CYP102A15 and CYP102A170, as Long-Chain Fatty Acid Hydroxylases

  • Rimal, Hemraj;Lee, Woo-Haeng;Kim, Ki-Hwa;Park, Hyun;Oh, Tae-Jin
    • Journal of Microbiology and Biotechnology
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    • 제30권5호
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    • pp.777-784
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    • 2020
  • Self-sufficient P450s, due to their fused nature, are the most effective tools for electron transfer to activate C-H bonds. They catalyze the oxygenation of fatty acids at different omega positions. Here, two new, self-sufficient cytochrome P450s, named 'CYP102A15 and CYP102A170,' from polar Bacillus sp. PAMC 25034 and Paenibacillus sp. PAMC 22724,respectively, were cloned and expressed in E. coli. The genes are homologues of CYP102A1 from Bacillus megaterium. They catalyzed the hydroxylation of both saturated and unsaturated fatty acids ranging in length from C12-C20, with a moderately diverse profile compared to other members of the CYP102A subfamily. CYP102A15 exhibited the highest activity toward linoleic acid with Km 15.3 μM, and CYP102A170 showed higher activity toward myristic acid with Km 17.4 μM. CYP10A170 also hydroxylated the Eicosapentaenoic acid at ω-1 position only. Various kinetic parameters of both monooxygenases were also determined.

연안해역에서 분변오염의 생화학적 지표(coprostanol)에 관한 연구 (Studies on biochemical indicator(coprostanol) of fecal pollution at coastal waters)

  • 강헌;여환구
    • 한국해양환경ㆍ에너지학회지
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    • 제4권3호
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    • pp.40-52
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    • 2001
  • 분변성 생화차적 지표인 coprostanol(5-cholestan-3-ol)을 이용하여 1997년 여름에서 1998년 겨울에 걸쳐 낙동강 하구와 진해만에서 분변오염의 정도를 조사·연구하였다. Coprostanol은 사람을 포함한 포유동물의 분변에서만 발견되므로 분변오염에 대한 유용한 추적자로 사용된다. 조사결과 coprostanol은 기존의 분변오염의 지표로 사용되는 분변계 대장균이나 암모니아보다 주변환경의 변화를 덜 받았으며 좋은 지표로 나타났다. 따라서 coprostanol과 그 계열의 성분들을 장기적으로 관찰하면 분변유입으로 인한 해양환경 및 해양생태계에 미치는 영향에 대한 지표로 유용하게 사용학 수 있는 것을 국내연안에 적용해 보았다.

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Cardiocirculatory, biochemical and hemostatic evaluation of dogs with hyperadrenocorticism at diagnosis and after treatment

  • Soares, Frederico Aecio Carvalho;Matheus, Juliana Pereira;Carvalho, Guilherme Luiz;Neuwald, Elisa Barp;Poppl, Alan Gomes;Valle, Stella Faria;Gonzalez, Felix Hilario Diaz
    • 대한수의학회지
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    • 제56권3호
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    • pp.161-166
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    • 2016
  • Hyperadrenocorticism (HAC) is a common endocrinopathy among dogs that causes multisystemic signs. This study was conducted to evaluate cardiocirculatory, biochemical, and hemostatic parameters in dogs with HAC at diagnosis, in addition to verifying whether abnormal parameters could be controlled by initial treatment with trilostane. Fifteen dogs with HAC were assessed by systolic blood pressure measurement, electrocardiography, Doppler echocardiography, serum concentration of troponin I, and biochemical and hemostatic profile at diagnosis and after trilostane therapy. Unlike biochemical parameters, hemostatic and cardiocirculatory parameters were not significantly influenced by the onset of treatment. The authors believe that clinical treatment with trilostane for 3 to 4 months might not be sufficient for the stabilization of cardiocirculatory abnormalities such as hypertension. Therefore, dogs with HAC must receive cardiocirculatory monitoring at diagnosis and during drug treatment.

나군대 잎의 약리 효과에 관한 연구 (Pharmacological Actions of Crinum folium)

  • 이송득;이상훈;최수완;권원준;김일혁
    • 생약학회지
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    • 제26권2호
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    • pp.139-147
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    • 1995
  • Crinum asiaticum var. japonicum is a wild plant growing only in Jeju-island, Korea, and in Japan. The whole part of this plant has been known to have the pharmacological actions such as analgesic, anti-inflammatory, platelet-aggregation inhibitory, antitussive, and expectorant. With these assumed actions, the leaves (Crinum folium) of this plant has been used in the folk remedies for arthritis and arthralgia. There is, however, no scientific evidences for the pharmacological actions of Crinum asiaticum var. japonicum. In the present study, the analgesic, anti-inflammatory, and platelet-aggregation inhibitory actions of Crinium folium were evaluated using writhing test, tail-flick test, carrageenin antiedema test, in vitro thromboxane $B_2$ quantitation assay and in vitro platelet aggregation test. In order to obtain the partially purified fraction whose pharmacological action is excellent, the methanol extract of Crinium folium was fractionated consecutively into four biological fractions such as ether, ethyl acetate, butanol, and water fractions and their pharmacological actions of the fractions were investigated. Putting our results together, Crinium folium, especially ethyl acetate fraction was proven to have significant analgesic, anti-inflammatory and platelet-aggregation inhibitory actions by inhibition of prostanoids biosynthesis as one of its mechanism of action.

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Biochemical Changes during Embryonic Diapause in Domestic Silkworm, Bombyx mori L. (Lepidoptera: Bombycidae)

  • Singh, Tribhuwan;Saratchandra, Beera
    • International Journal of Industrial Entomology and Biomaterials
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    • 제5권1호
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    • pp.1-12
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    • 2002
  • Ecophysiologically diapause represents a syndrome of physiological and biochemical characteristics, all of which ensure survival during a long period of dormancy. Since, silkworm enters diapause as embryo at the early embryonic stage, the duration of egg life depends on the duration of embryonic diapause. The nature of diapause in silkworm, Bombyx mori, is primarily determined by genetic characters and endocrinologicnl mechanisms, mediated by environmental factors such as temperature and photoperiod. Hibernating potency value besides nucleic acid and carbohydrate metabolism, production and utilization of sorbitol are also equally responsible for induction, initiation, determination, maintenance and termination of diapause. Embryonic diapause in Bombyx moir, induced by active secretion of sub-oesophageal ganglion is attributed to hormonal system and metabolic adjustment, which serves to bring about a new physiological state. Metabolic conversion of trehalose to glycogen at induction, glycogen to sorbitol at initiation and sorbitol to glycogen at termination of diapause is correlated and in each metabolic shift a key enzyme becomes active in response to hormonal and environmental stimulation. An attempt has been made in this review article to discuss briefly the nature of embryonic diapause, influence of various factors on diapause nature, hormonal mechanism of diapause besides biochemical composition of egg, nucleic acid and carbohydrate metabolism, production and utilization of sorbitol in relation to induction, determination, maintenance, initiation and termination of diapause in the silkworm, Bombyx mori.