• Title/Summary/Keyword: $MgCl_2\

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Effect of Chronic Alcohol Feeding and 2-Acetylaminofluorene Treatment on Hepatic Mitochondrial ATPase Activity and Membrane Lipid Composition in Rats (만성 알코올 섭취시 2-Acetylaminofluorene 투여가 흰쥐 간 미토콘드리아 ATPase 활성도와 막지질 조성에 미치는 영향)

  • 김정희;류선영
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.6
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    • pp.867-873
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    • 1995
  • This study was done ot investigate the effect of chronic alcohol feeding and acetylaminofluorene(2-AAF) treatment on hepatic mitochondrial ATPase activity andmembrane lipid composition. Male Sprague-Dawley rats, weighing 120~125g, were fed for 6 weeks on a liquid diet containing 35% of calories as ethanol. After 4 weeks of experiment diet feeding, 2-AAF(100mg/kg body weight) was injected twice a week intraperitoneally. Body weight and percent liver weight per body weight were significantly changed by ethanol feeding. Hepatic mitochondrial ATPase activity significantly decreased by ethanol feedings but not by 2-AAF treatment. In comparison to control, the ATPase activity of ethanol-AAF group decreased 29.3%. Since phospholipid(PL) content of mitochondria has an interaction effect between ethanol and 2-AAF treatment, 2-AAF treatment significantly increased phospholipid content in only ethanol fed group. Total cholesterol(C) level of mitochondria significantly increased by ethanol feeding. Consequently C/PL ratio of ethanol group was significantly higher than that of control group. The analysis of mitochondrial PL composition showed that cardiolipin(CL) significantly increased by 2-AFF treatment in control group. Phosphatidyl choline(PC) significantly increased by ethanol feeding, whereas PC significanlty decreased and phosphatidyl ethanolamine(PE) significantly increased by 2-AAF treatment. 2-AAF treatment also showed a significant increase in PE/PC ratio. Fatty acid patterns of mitochondria were also changed by either ethanol or 2-AAF although the severity of the changes was not great. These data suggest that the reduced mitochondrial ATPase activity in ethanol-AAF group may be a consequence of a changes in mitochondrial membrane lipid composition such as PE/PC ratio, C/PL ration and fatty acid patterns.

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Effect of Genistein on the Onset of Puberty in Female Rats (암컷 흰쥐의 사춘기 개시에 미치는 Genistein의 효과)

  • Lee, Kyeung-Yeup;Lee, Sung-Ho
    • Development and Reproduction
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    • v.10 no.1
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    • pp.55-61
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    • 2006
  • There is growing concern that dietary soy intake is associated with protection of breast cancer. However, questions persist on the potential adverse effects of the main soy constituent genistein(GS) on female reproductive physiology. In this study, we examined whether prepubertal exposure to GS affected on the onset of puberty and the associated reproductive parameters such as hormone receptor expressions in female rats. GS(100mg/kg/day) was administrated daily from postnatal day 25(PND 25) to the day when the first vaginal opening(VO) was observed, and the animals were sacrificed on the day after VO occurred. Gross anatomy and tissue weight were compared to test the GS's effect on the cell proliferation. Furthermore, histological studies were performed to assess the structural alterations in tissues. Specific radioimmunoassay(RIA) were carried out to measure serum LH levels. To determine the transcriptional changes in progesterone receptors(PR), total RNAs were extracted from ovary and uterus and were applied to semi-quantitative reverse transcription polymerase chain reaction(RT-PCR). As a results, advanced VO was shown in the GS group(PND $31.2{\pm}0.6$) compared to the vehicle group (PND $35.3{\pm}0.7$). GS treatment significantly increased wet weight of ovaries and uteri compared to the vehicle group. Increased serum LH levels were also shown in the GS group. Graafian follicles and corpora lutea(CL) were observed only in the ovaries from GS treated animals. Similarly, hypertrophy of luminal and glandular uterine epithelium were found only in the GS group. Collectively, these effects were probably due to the estrogenic effects of GS. In the semi-quantitative RT-PCR studies, the transcriptional activities of PR in both ovary and uterus from GS-treated group were significantly higher than those from the vehicle group. The present studies demonstrated that acute exposure to GS, at levels comparable to the ranges of human exposure, during the critical period of prepubertal stage activates the reproductive system resulting precocious puberty in immature female rats.

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Effect of Cropping System and Application of Cattle Slurry on Forage Production and Environmental Pollution in Paddy Land (논에서 경작형태와 우분액비 시용이 사초생산성 및 환경오염에 미치는 영향)

  • Choi, Ki-Choon;Na, Sang-Pil;Kim, Won-Ho;Choi, Gi-Jun;Kim, Young-Chul;Kim, Myeong-Hwa;Lee, Sang-Lak;Kim, Da-Hye;Yook, Wan-Bang
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.32 no.3
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    • pp.309-316
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    • 2012
  • This study was performed to investigate the effects of forage cropping system and cattle slurry on productivity of whole crop rice, whole crop barley and Sorghum-Sudangrass hybrid and environmental pollution in paddy land. Forage cropping system used in this study was consisted of double-cropping whole crop barley followed by whole crop rice applied with cattle slurry (DWBRC) and double-cropping whole crop barley followed by Sorghum-Sudangrass hybrid applied with cattle slurry (DSSBC). The field experiments were conducted on the clay loam at Backsanmyun, Kimje, Chunlabukdo province in Korea for three years (May 2006 to Apr. 2009). This study was arranged in completely randomized design with three replicates. The field had been sown with whole crop rice 'Nampyung', Sorghum-Sudangrass hybrid 'Sordan79' and whole crop barley 'Younyang'. The yields of whole crop barley in DWBRC and DSSBC were 7,515 kg/ha and 8,515 kg/ha, respectively. The yields of whole crop barley in DSSBC significantly increased as compared with that of DWBRC (p<0.05). The contents of crude protein, neutral detergent fiber (NDF), acid detergent fiber (ADF), total digestible nutrient (TDN) of whole crop barley in DWBRC were not difference as compared with those of DSSBC. The pH, and contents of total nitrogen and organic matter in soil samples collected at the end of the experiment increased as compared with those at the beginning of the experiment (p<0.05). However, The content of phosphate in DWBRC was no difference as compared with DSSBC. In addition, after the end of experiment, the concentrations of exchangeable cations (Ca, Na, Mg and K) in soil samples collected at the end of the experiment were remarkably higher than those at the beginning of the experiment (p<0.05). The concentrations of $NH_4$-N, $NO_3$-N, $PO_4$-P, Cl, Ca, K, Mg and Na in leaching water were hardly influenced by the cropping system and application of cattle slurry.

Studies on the Meat Production and Woolskin Processing of Sheep and Korean Native Goats for Increasing Farm Income as a Family Subsidiary Work (농가부업(農家副業)의 소득향상(所得向上)을 위한 양육생산(羊肉生産) 및 모피가공(毛皮加工)에 관(關)한 연구(硏究))

  • Kwon, Soon-Ki;Kim, Jong-Woo;Han, Sung-Wook;Lee, Kyu Seung
    • Korean Journal of Agricultural Science
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    • v.5 no.2
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    • pp.93-114
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    • 1978
  • The purpose of the study was to find out possible ways for increasing farm income through the sheep and Korean native goats farming, and to investigate meat productivity, wool productivity; woolskin utility, physiological characteristics and correlation between economical college animal farm of the Chungnam National University and sample farms in the suburbs of Dae jeon City were selected for feeding 20 heads of Corriedale wethers and another 20 heads Korean native kids as research materials for the periods of 5th May-26th November, 1977. The data such as growth rate, carcass, viscera weight, blood picture and plamsa components, hebage intake and economic traits were obtained and analysed. The result of the study are summarized as follows: 1. Meat production and quality 1) After 196days of feeding, the body weight of sheep and Korean native goats was increased by two times of those at the beginning of the trial, i.e. 20kg and 8kg respectively. 2) There was no significance of growth rates of sheep in housing and grazing. 3) The growth rate of Korean native goats were excellent at the mountainous areas of Gong ju-Gun where infectious diseases were not found 4) Accroding to the body measurements of 18-month-old sheep, percentages of hip height, body length, rump length, chest depth, chest width, hip width, chest girth and forearm circumference to the withers height were 103,%, 104%, 33%, 44%, 31%, 23%, 135% and 15% respectively, and those of hip height, body length, chest depth and chest girth of 8-month-old native goats to the withers height were 106%, 109%, 46% and 122,% respecitively. As a result, it was found that the percentage of hip height, body length and chest depth of Korean native goats were higher than those of sheep while that of the chest girth of goats was lower. 5) In the carcass data, 47, $52{\pm}2.27%$ of carcass percentage, $34.61{\pm}1.62%$ of lean meat, $26.07{\pm}2.51%$ of viscera, $9.75{\pm}1.4%$ of bone, and $20.95%{\pm}2.14%$ of woolskin for sheep, and $45.58{\pm}5.63%$ of carcass percentage, $27.62{\p}3.81%$ of meat, $34.86{\pm}4.16%$ of viscera, $11.66{\pm}1.83%$ of bone, $3.63{\pm}1.61%$ of skull and $9.26{\pm}2.41%$ of woolskin for native goats were obtained. 6) The contents of moisture, crude protein, crude fat and crude ash in native goat meat were much similar in both plots of housing and grazing. It was, however, known that the contents of moisture and protein were higher in grazinrg than in housing, while fat content was lower in grazing plots. 7) The weights of visceral organs shown similar tendency for both of sheep and native goats. For the weights of liver, heart, kidney and spleen, significance was not reconized among the treatments. Those of rumen, reticulum, small and large intestine were heavier in grazing than in housing, while the amount of visceral fat was heavier in housing. 2. Wool productivity and woolskin 1) The wool production of sheep for 7 months was $3.88{\pm}1.02kg$, and wool percentage, staple length, straighten length, wool growth per day and number of crimps were $9.27{\pm}1.48%$, 8. $47{\pm}1.00cm$, $10.63{\pm}0.99cm$, $0.40{\pm}0.04cm$ and $2.78{\pm}0.40$ respecitively. 2) The tensile strength and tear strength of woolskin treated by alum tanning were highest on the skin obtained from rump, i.e. $1,351kg/mm^2$ and $2,252kg/mm^2$ respectively, and they are in order of loin and shoulder. 3. Utilization and improvement of pasture. 1) The difference of herbage intake of native goats was not recognized between grazing and tethering, but the intake in the afternoon was s lightly higher than that in the morning. However the hervage intake of sheep was superior in grazing and in the afternoon. 2) The cultivation effect was lower in the native goat plots due to their cultivation abilities, in other words, the establishment rates of pasture by hoof cultivation were 60.25% in the goat plots and 77.35% in the sheep plots. 4. Correlation among economical traits. 1) The correlation between live weight of sheep and daily gain was higher. On the other hand, the correlation between other traits was not significant except that live weight, daily gain and lean meat percentage to the length of thoracic vertebrae. The live weight of native goats and meat production were highly correlated, and high correlation was also found between weights of carcass and meat. However, negative correlation was shown between viscera weight and live weight as well as daily gain. 2) The correlatoin between fleece weight of sheep and other traits such as live weight, daily gain and fleece percentage is very high at the 1% siginficant level, and this means that rapid-growth individuals can produce much fleece. 3) The correlation between the factors such as weights of live body, lean meat and viscera of sheep and body measurements, i. e. chest girth and body length was highest, and weights, of carcass and lean meat was highly correlated to chest width and depth. It will be therefore reasonable that the meat productivity estimates will have to be made on the basis of chest girth and body length. The meat production traits of native goats were highly correlated to the most of body measurement data, and the correlation coefficient between chest girth and weights of live body, carcass, lean meat and bone percentage was very high, i. e. 0.992-0.974 in particular. The correlations of meat production traits to chest depth, forearm circumference, body length were 0.759-0.911, 0.759-0.909 and 0.708-0.872 respectively. Therefore, the meat production of native goats will have to be estimated on the basis of chest data. 5. Blood picture and plasma components. 1) The number of erythrocyte and MCHC of native goats were $12.93{\times}10^6/mm^3$ and 36.14%, and those of sheep were $10.68{\times}10^6/mm^3$ and 36.26 respectively. The values of native goats were significantly higher than those of sheep. 2) The hemoglobin concentration, PVC, MCV and MCR of native goats were 10.92 g/100ml, $23.40{\mu}^3$ and 10.94 pg, and those of sheep were 11.73 g/100ml, 36.25 ml/100ml, $33.97{\mu}^3$ and 30.2 ml/100ml 8.43 pg respectively. The values of native goats were significantly lower those of sheep. 3) The number of leukocytes of native goats was significantly higher than that of sheep, that is, $11.64{\times}10^3/mm^3$ in native goats and $9.32{\times}10^3/mm^3$ in sheep. 4) In differential count of leukocyte, neutrophil was significantly high in native goats while lympocyte in sheep. On the other hand, the basophil, eosinophil and monocyte were not significant between native goats and sheep. 5) The amounts of total protein and glucose in the plasma of native goats were 6.2g/100ml and 53.6mg/100ml, and those of sheep were 5.6g/100ml and 45.7mg/100ml, which means that the values of native goats were significantly higher that those of sheep. The amount of total-lipid of native goats(127.6mg/100ml) was significantly than that of sheep(149.6mg/100ml). 6) The amount of non-protein nitrogen, cholesterol, Ca, P, K, Na and Cl were not different between native goats and sheep. 6. Economic analysis. 1) The gross revenue of a farm which fed native goats and sheep was 4,000won per head and the optimum size for feeding them in a farm as a subsidiary work is 5-10 heads. 2) Since there was no difference between housing and grazing, they can be fed in group for farm's subsidiary work. 3) They can be also fed by youths and house wives in the suburbs of cities, because labour requirement is estimated as only two hours per days for feeding 5 heads of native goats and sheep.

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A Scientific Analysis of Ancient Pigments on Wall Paintings at Yeongsanjeon in Tongdo Temple Using a Field-XRF (휴대용X선형광분석기를 이용한 통도사 영산전 벽화 안료의 과학적 성분분석)

  • Han, Min Su;Lee, Han Hyoung;Kim, Jae Hwan
    • Korean Journal of Heritage: History & Science
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    • v.44 no.3
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    • pp.132-149
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    • 2011
  • In ancient period, a variety of inorganic or organic pigments had been used as colorants in various kinds of religious and secular paintings such as tomb paintings and wall and scroll paintings in buddhist temples, and danchung(cosmic patterns) for the surface of wooden buildings. This study discusses the results obtained from an analysis of the pigments on the wall paintings of Yeongsanjeon(Hall of Vulture Peak) in Tongdo temple by a qualitative analysis using a field-XRF. The results can be briefly summarized as follows. Firstly, assuming from the major components examined from F-XRF analysis, raw materials of pigment of each color are: red to be Cinnabar(HgS) or Hematite($Fe_2O_3$); white to be White Lead[$2PbCO_3{\cdot}Pb(OH)_2$] in most cases and Calcite($CaCO_3$) or Chalk($CaCO_3$), Kaolin($Al2O_3{\cdot}SiO_2{\cdot}4H_2O$) in some cases; yellow to be Yellow Ocher[$FeO(OH){\cdot}nH_2O$]; black to be carbon(C); green on the painted surface to be Celadonite[$K(Mg,Fe^{2+})(Fe^{3+},Al)(Si_4O_{10})(OH)_2$] in most cases; dark green on the halo of figures to be Malachite[$CuCO_3{\cdot}Cu(OH)_2$], Copper Green[$2CuO{\cdot}CO_2{\cdot}H_2O$] or Atacamite[$Cu_2Cl(OH)_3$]. Secondly, incarnadine and pink were made by mixing with more than two pigments such as red and white for making various tone of colors. The qualitative analysis of pigments on the wall paintings of Yeongsanjeon, in conclusion, displays that the all pigments for ancient periods are inorganis pigments. However, it has the limitation to identify a definite kinds of mineral for each pigment because it was not possible to collect samples from cultural heritage for conducting a crystalline analysis of XRD.

Isolation and Morphological Identification of Fresh Water Green Algae from Organic Farming Habitats in Korea (유기농업 생태계로부터 담수 녹조류 분리 및 형태적 동정)

  • Kim, Min-Jeong;Shim, Chang-Ki;Kim, Yong-Ki;Hong, Sung-Jun;Park, Jong-Ho;Han, Eun-Jung;Jee, Hyeong-Jin;Yun, Jong-Chul;Kim, Suk-Chul
    • Korean Journal of Organic Agriculture
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    • v.22 no.4
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    • pp.743-760
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    • 2014
  • This study aimed to isolate and identify freshwater algae from the organic agricultural ecosystems and investigate its biological characteristics to study the possibility of utilizing a biomass freshwater algae in organic farming. In the survey area, average water temperature was $12.4{\sim}28.2^{\circ}C$ and the pH ranges were from 6.1 to 8.5. The solid culture method is more suitable than liquid culture method for isolation of freshwater algae with lower contamination level and higher isolation frequency. A total of 115 strains were isolated from six freshwater algae habitats in nine regions in Korea. BGMM (BG11 Modified Medium) amended with NaNO3 and $KNO_3$ as a nitrogen, and $Na_2CO_3$ as carbon source was designed to isolate and culture freshwater algae. Absorbance of freshwater algae culture has increased dramatically to four days and decreased after eight days after inoculation. CHK008 of the seven isolates showed the highest absorbance in seven days after culturing in BGMM. The optimal pH of BGMM for culturing freshwater algae was pH 6-7. As light intensity increased, growth of freshwater algae increased. Among the five kinds of carbon sources, glucose and galactose promoted good growth of freshwater algae in BGMM. The colony color of purified 16 green algae isolates showed a separation of green, dark and light green, and of them, eleven algae strains showed a strong fluorescent light under fluorescence microscopy. Cell size of the green algae showed a wide range of variation depending on the species. General morphology of the green algae strains was spherical. Chlamydomonas sp. was elliptical, and Chlorella sorokiniana was ellipsoidal and cylindrical. All strains of the green algae except for Chlamydomonas sp. did not have flagella. One isolate of Chlamydomonas sp. and five isolates of C. sorokiniana secreted mucus. Sixteen isolates of 16 green algae were identified as two family and six species, Chlorella vulgalis, C. sorokiniana, C. pyrenoidosa, C. kessleri, C. emersonii, and Chlamydomonas sp. based on their morphological characteristics.

Janggunite, a New Mineral from the Janggun Mine, Bonghwa, Korea (경북(慶北) 봉화군(奉化郡) 장군광산산(將軍鑛山産) 신종광물(新種鑛物) 장군석(將軍石)에 대(對)한 광물학적(鑛物學的) 연구(硏究))

  • Kim, Soo Jin
    • Economic and Environmental Geology
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    • v.8 no.3
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    • pp.117-124
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    • 1975
  • Wet chemical analysis (for $MnO_2$, MnO, and $H_2O$(+)) and electron microprobe analysis (for $Fe_2O_3$ and PbO) give $MnO_2$ 74.91, MnO 11.33, $Fe_2O_3$ (total Fe) 4.19, PbO 0.03, $H_2O$ (+) 9.46, sum 99.92%. 'Available oxygen determined by oxalate titration method is allotted to $MnO_2$ from total Mn, and the remaining Mn is calculated as MnO. Traces of Ba, Ca, Mg, K, Cu, Zn, and Al were found. Li and Na were not found. The existence of (OH) is verified from the infrared absorption spectra. The analysis corresponds to the formula $Mn^{4+}{_{4.85}}(Mn^{2+}{_{0.90}}Fe^{3+}{_{0.30}})_{1.20}O_{8.09}(OH)_{5.91}$, on the basis of O=14, 'or ideally $Mn^{4+}{_{5-x}}(Mn^{2+},Fe^{3+})_{1+x}O_{8}(OH)_{6}$ ($x{\approx}0.2$). X-ray single crystal study could not be made because of the distortion of single crystals. But the x-ray powder pattern is satisfactorily indexed by an orthorhombic cell with a 9.324, b 14.05, c $7.956{\AA}$., Z=4. The indexed powder diffraction lines are 9.34(s) (100), 7.09(s) (020), 4.62(m) (200, 121), 4.17(m) (130), 3.547(s) (112), 3.212(vw) (041), 3.101(s) (300), 2.597(w) (013), 2.469(m) (331), 2.214(vw)(420), 2.098(vw) (260), 2.014 (vw) (402), 1.863(w) (500), 1.664(w) (314), 1.554(vw) (600), 1.525(m) (601), 1.405(m) (0.10.0). DTA curve shows the endothermic peaks at $250-370^{\circ}C$ and $955^{\circ}C$. The former is due to the dehydration: and oxidation forming$(Mn,\;Fe)_2O_3$(cubic, a $9.417{\AA}$), and the latter is interpreted as the formation of a hausmannite-type oxide (tetragonal, a 5.76, c $9.51{\AA}$) from $(Mn,\;Fe)_2O_3$. Infrared absorption spectral curve shows Mn-O stretching vibrations at $515cm^{-1}$ and $545cm^{-1}$, O-H bending vibration at $1025cm^{-1}$ and O-H stretching vibration at $3225cm^{-1}$. Opaque. Reflectance 13-15%. Bireflectance distinct in air and strong in oil. Reflection pleochroism changes from whitish to light grey. Between crossed nicols, color changes from yellowish brown with bluish tint to grey in air and yellowish brown to grey through bluish brown in oil. No internal reflections. Etching reactions: HCl(conc.) and $H_2SO_4+H_2O_2$-grey tarnish; $SnCl_2$(sat.)-dark color; $HNO_3$(conc.)-grey color; $H_2O_2$-tarnish with effervescence. It is black in color. Luster dull. Cleavage one direction perfect. Streak brownish black to dark brown. H. (Mohs) 2-3, very fragile. Specific gravity 3.59(obs.), 3.57(calc.). It occurs as radiating groups of flakes, flower-like aggregates, colloform bands, dendritic or arborescent masses composed of fine grains in the cementation zone of the supergene manganese oxide deposits of the Janggun mine, Bonghwa-gun, southeastern Korea. Associated minerals are calcite, nsutite, todorokite, and some undetermined manganese dioxide minerals. The name is for the mine, the first locality. The mineral and name were approved before publication by the Commission on New Minerals and Mineral Names, I.M.A.

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A STUDY OF THE MECHANISM OF IMPROVING ACID RESISTANCE OF BOVINE TOOTH ENAMEL AFTER PULSED Nd-YAG LASER IRRADIATION (펄스형 Nd-YAG 레이저 조사에 의한 법랑질 내산성 증가 기전에 관한 연구)

  • Lee, Young-Soon;Shon, Heung-Kyu
    • Journal of the korean academy of Pediatric Dentistry
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    • v.23 no.3
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    • pp.640-658
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    • 1996
  • The purpose of this study was to examine the mechanism of improving acid resistance of Nd-YAG laser irradiated tooth enamel and determine the most effective energy density for improving acid resistance. The bovine tooth enamel were lased with a pulsed Nd-YAG laser. The energy densities of exposed laser beam were varied from 10 to $70\;J/cm^2$. To investigate the degree of improving acid resistance by irradiation, all the samples were submerged to demineralize in 0.5 N $HClO_4$ solution for 1 minute. After 1 minute, 0.05 % $LaCl_3$ was added to the solution for interrupting the demineralization reaction. The amounts of dissolved calcium and phosphate in the solution were measured by using an atomic absorption spectrophotometer and the UV/VIS spectrophotometer, respectively. To examine the mechanism of improving acid resistance, X-ray diffraction analysis, infrared spectroscopy, and scanning electron microscopy were taken. The X-ray diffraction pattern of the samples were obtained in the $10^{\circ}{\sim}80^{\circ}2{\theta}$ range with $Cu-K{\alpha}$ radiation using M18HF(Mac Science Co.) with X-ray diffractometer operating at 40 KV and 300 mA. The infra-red spectra of the ground samples in 300 mg KBr pellets 10 mm diameter were obtained in the $4000cm^{-1}\;to\;400cm^{-1}$ range using JASCO 300E spectrophotometer. The scanning electron microscopy was carried out using JSM6400(JEOL Co.) with $500{\sim}2000$ times magnification. The results were as follow 1. The concentration of calcium dissolved from laser irradiated enamel with $50J/cm^2$ was significantly lesser than that of unlased control group (p<0.05) 2. From the result of the X-ray diffraction analysis, $\beta$-TCP, which increases acid solubility, was identified in lased enamel but the diffraction peaks of (002) and (004) became sharp with increasing energy density of laser irradiation. This means that the crystals in lased samples were grown through the c-axis and subsequently, the acid solubility of enamel decreased. 3. The a-axis parameter was slightly increased by laser irradiation, whereas the c-axis parameter was almost constant except for a little decrease at $50J/cm^2$. 4. In the infra-red spectra of lased enamels, phosphate bands ($600{\sim}500cm^{-1}$), B-carbonate bands (870, $1415{\sim}1455cm^{-1}$), and A-carbonate band ($1545cm^{-1}$) were observed. The amounts of phosphate bands and the B-carbonate bands were reduced, on the other hand, the amount of the A-carbonate band was increased by increase the energy density. 5. The SEM experiments reveal that the surface melting and recrystallization were appeared at $30J/cm^2$ and the cracks were observed at $70J/cm^2$. From above results, It may be suggested that the most effective energy density for improving acid resistance of tooth enamel with the irradiation of Nd-YAG laser was $50J/cm^2$. The mechanism of improving acid resistance were reduction of permeability due to surface melting and recrystallization of lased enamel and reduction of acid solubility of enamel due to decrease of carbonate content and growth of crystal.

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Comparison of Inflammatory Response and Myocardial injury Between Normoxic and Hyperoxic Condition during Cardiopulmonary Bypass (체외순환 시 정상 산소분압과 고 산소분압의 염증반응 및 심근손상에 관한 비교연구)

  • 김기봉;최석철;최국렬;정석목;최강주;김양원;김병훈;이양행;조광현
    • Journal of Chest Surgery
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    • v.34 no.7
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    • pp.524-533
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    • 2001
  • Background: Hyperoxemic cardiopulmonary bypass (CPB) has been recognized as a safe technique and is widely used in cardiac surgery. However, hyperoxemic CPB may produce higher toxic oxygen species and cause more severe oxidative stress and ischemia/reperfusion injury than normoxemic CPB. This study was undertaken to compare inflammatory responses and myocardial injury between normoxemic and hyperoxemic CPB and to examine the beneficial effect of normoxemic CPB. Material and method: Thirty adult patients scheduled for elective cardiac surgery were randomly divided into normoxic group (n=15), who received normoxemic CPB (about Pa $O_{2}$ 120 mmHg), and hyperoxic group (n=15), who received hyperoxemic CPB (about Pa $O_{2}$ 400 mmHg). Myeloperoxidase (MPO), malondialdehyde (MDA), adenosine monophosphate (AMP), and troponin-T (TnT) concentrations in coronary sinus blood were determined at pre- and post-CPB. Total leukocyte and neutrophil counts in arterial blood were measured at the before, during, and after CPB. Lactate concentration in mixed venous blood was analyzed during CPB, and cardiac index (Cl) and pulmonary vascular

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Isolation of Marine Bacteria Killing Red Tide Microalgae -IV. Characteristics of Algicidal Substances, Produced from Micrococcus sp. LG-5 and the Effects on Marine Organisms- (적조생물 살조세균 탐색 -IV. 살조세균 Micrococcus sp. LG-5가 생산하는 살조물질의 특성과 해양생물에 미치는 영향-)

  • JEONG Seong-Youn;PARK Young-Tae;KIM Mu-Chan;CHOI Seok-Cheol;SEONG Hee-Kyung;KIM Jai-Young;KIM Tae-Un;LEE Won-Jae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.33 no.4
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    • pp.339-347
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    • 2000
  • An algicidal bacterium, Micrococcus sp. LG-5 against the harmful dinoflagellate, Cochlodinium polykrikoides was isolated. The optimal conditions for the highest algicidal activity of bacterial culture filtrate showed in the range of $20{\~}30^{\circ}C$, at pH 7.0 and $3.0{\%}$ of NaCl concentration. In addition, $IC_(50)(mean of 50{\%} inhibitory concentration)$ of the culture filtrate against C. polykrikoides after incubation of 5 days was $0.482{\%}$. To investigate heat and pH stability of the culture filtrate of Micrococcus sp. LG-5, the culture filtrate ($pore size, 0.1 {\mu}m$) was heated to $121^{\circ}C for 15 min$ and adjusted pH from 2.0 to 10.0. There were no significant changes in algicidal activity by heat treatment and the pH change between pH from 5.0 to 10.0. The algicidal substances produced from Micrococcus sp. LG-5 were mainly detected in the fraction of $10,000{\~}1,000$ MWCO (molecular weight cut-off). The culture filtrate of Micrococous sp. LG-5 showed antimicrobial activity against Enterococcus faecalis, Escheiichia coli, Uebsiella pneunioniae and Vibrio altinolyticus, but did not show against Pseudomonas aeminosa, P. Buorescens, Salmonella typhi, Staphylococcus aureus, V. cholerae and V parahaemolyicus. The culture filtrate of Micrococcus sp. LG-5 was examined against 16 phytoplankton species and showed the algicidal activity against Ajexandzium tuarense, Eutreptiella Drnnastin, Gymnodinium catenatum, G. mikimotoi, G. sanguineum, eyodinium impuaicum, Heterocapsa triquetra, Heterosipa akashiwo, Prorocentrum micans and Pyraminonas sp.. However no algicidal effects of Micrococcus sp. LG-5 were observed against Chlamydomonas sp., Cylindrotheoa closterium, P. mininum, P. triestimum, Pseudonieschia sp. and Sczipuiella trochoidea. On the other hand, algicidal activity on the tested marinelivefood was not detected except for Isochrysis galbana. In addition, physiological responses of cultured olive flounder (Paralichthys oliraceus) exposed to $1 and 10{\%}$ of the culture filtrate of Micrococcus sp. LG-5 were measured. There were no clear changes in AST, GGT, creatinine, urea, total cholesterol, total protein, albumine, $Mg^(+2), Ca^(+2), Na^+, K^+, and Cl^-$. These results indicate that olive flounders were not affected when they were exposed to the culture filtrate of Micrococcus sp. LG-5.

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