• Title/Summary/Keyword: Rate-Control

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A Study on the Post-Receptor Mechanism of Adenosine Receptor on Norepinephrine Release in the Rat Hippocampus (흰쥐 해마에서 Norepinephrine 유리에 미치는 Adenosine Receptor의 Post-Receptor 기전에 관한 연구)

  • Choi, Bong-Kyu;Kim, Do-Kyung;Yang, Kyung-Moo
    • The Korean Journal of Pharmacology
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    • v.32 no.1
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    • pp.1-11
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    • 1996
  • Since it has been reported that the depolarization-induced norepinephrine (NE) release is inhibited by activation of presynaptic $A_1-adenosine$ heteroreceptor in hippocampus, a large body of experimental data on the post-receptor mechanism of this process has been accumulated. But, the post-receptor mechanism of presynaptic $A_1-adenosine$ receptor on the NE release has not been clearly elucidated yet. Therefore, it was attempted to clarify the post-receptor mechanisms of the $A_1-adenosine$ receptor-mediated control of NE release in this study. Slices from rat hippocampus were equilibrated with $^3H-norepinephrine$ and the release of the labelled products was evoked by electrical stimulation (3 Hz, 5 $Vcm^{-1}$, 2 ms, rectangular pulses), and the influence of various agents on the evoked tritium-outflow was investigated. Adenosine, in concentrations ranging from $1{\sim}30{\mu}M$, decreased the NE release in a dose-dependent manner, without affecting the basal rate of release. The adenosine effects were significantly inhibited by 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, $2{\mu}M$), a selective $A_1-receptor$ antagonist. The responses to N-ethylmaleimide (NEM, 10 & $30{\mu}M$), a SH-alkylating agent of G-protein, were characterized by increments of the evoked NE-release and the basal release, and the adenosine effects were completely abolished by NEM pretreatment. $4{\beta}-Phorbol$ 12,13-dibutyrate (PDB, $1{\mu}M$), a specific protein kinase C (PKC) activator, increased the evoked NE release, whereas polymyxin B sulfate (PMB,0.1 mg), a PKC inhibitor, decreased the release, and the adenosine effects were inhibited by these agents. Nifedipine $(1{\mu}M)$, a $Ca^{2+}-channel$ blocker of dihydropyridine analogue, did not affect the adenosine effect. Tetraethylammonium (TEA, 3 mM) increased the evoked NE release, and inhibited the adenosine effects, but glibenclamide, a ATP dependent $K^+-channel$ blocker, did not. Finally, 8-bromo cyclic AMP (100 & $300{\mu}M$), a membrane-permeable analogue of cAMP, did not alter the NE release, but adenosine effects were inhibited by pretreatment with 8br-cAMP. These results suggest that the decrement of the evoked NE-release by $A_1-adenosine$ receptor is mediated by the C-protein, which is coupled to protein kinase C, adenylate cyclase system and TEA sensitive $K^+-channel$, and that nifedipine-sensitive $Ca^{2+}-channel$ and glibenclamide-sensitive $K^+-channel$ are not involved in this process.

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Effects of Dietary Fe Sources on Productivity and Egg Composition in Laying Hens (유기태 철과 효모 철의 첨가가 산란계의 생산성 및 난 성분에 미치는 영향)

  • Na S. J.;Uuganbayar D.;Oh J. I.;Sin I. S.;Jung D. K.;Kim H. Y.;Yang C. J.
    • Korean Journal of Poultry Science
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    • v.32 no.3
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    • pp.211-217
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    • 2005
  • This study was carried out to investigate the effects of Saccharomyces cerevisiae (wild yeast mutant), Saccharomyces cerevisiae hFeHLC (ferritin containgig yeast) and chelated Fe diets on the Productivity and egg qualify of laying hens. A total of 245 'Brown Tetra' layers 35 weeks aged was randomly alloted to seven dietary treatments : 1) control diet no iron added, 2) diet supplemented $0.1\%$ wild yeast mutant (YM03), 3) diet supplemented $1.0\%$ wild yeast mutant (YM03), 4) diet supplemented $0.1\%$ ferritin with yeast (YF04), 5) diet supplemented $1.0\%$ ferritin with yeast (YF04), 6) diet supplemented $0.01\%$ chelated Fe and 7) diet supplemented $0.1\%$ chelated Fe. The egg Production rate was significantly increased in layers 134 Fe supplemented diets (p<0.05). Egg weight was significantly reduced in layers fed $0.1\%$ chelated Fe diet (P<0.05). Fe content of egg yolk was significantly increased in $1.0\%$ YF04 and $0.1\%$ chelated Fe treatments (P<0.05). There were no significant differences in shape index, albumin index and yolk index of eggs of layers fed diets Fe supplementation (P>0.05). The haugh unit of eggs was significantly increased in layers fed YM03, YF04 and chelated Fe supplemented diets (p<0.05). TBA value of egg was significantly increased in different iron Fe treatments except of $0.1\%$ YM03 (P<0.05). The yolk cole. of eggs was significantly increased in $1.0\%$ YF04 diet (P<0.05).

Expression of Jun and p53 Genes from the Brain of Rats Irradiated with $^{60}Co{\gamma}$-ray (감마선 조사에 의한 뇌조직의 Jun 및 p53유전자 발현)

  • Kim Yong Seok;Woo Chong Kyu;Lee Yong Sung;Koh Jai Kyung;Chun Ha Chung;Lee Myung Za
    • Radiation Oncology Journal
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    • v.14 no.4
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    • pp.265-279
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    • 1996
  • Damage produced by radiation elicits a complex response in mammalian cells, including growth rate changes and the induction of a variety of genes associated with growth control and apoptosis. At doses of 10,000 cGy or greater, the exposed individual was killed in a matter of minutes to a couple of days, with symptoms consistent with pathology of the central nervous system(CNS) including degenerative changes. The nature of the damage in irradiated cells underlies the unique hazards of ionizing radiation. Radiation injury to CNS is a rare event in clinical medicine, but it is catastrophic for the patient in whom it occurs. The incidence of cerebral necrosis has been reported as high as 16% for doses greater than 6,000 cGy. In this study, the effect of radiation on brain tissue was studied in vivo. Jun and p53 genes in the rat brain were induced by whole body irradiation of rat with 600Co in doses between 1 Gy and 100 Gy and analyzed for expression of jun and p53 genes at the postirradiation time up to 6 hours. Northern analyses were done using 1.8 Kb & 0.8 Kb-pGEM-2-JUN/Eco RI/Pst I fragments, 2.0 Kb-php53B/Bam HI fragment and ,1.1 Kb-pBluescript SK--ACTIN/Eco RI fragment as the digoxigenin or [${\alpha}^{32}P$] dCTPlabeled probes for Jun, p53 and ${\beta}$-actin genes, respectively. Jun gene seemed to be expressed near the threshold levels in 1 hour after irradiation of $^{60}$Co in dose less than 1 Gy and was expressed in maximum at 1 hour after irradiation of $^{60}$Co in dose of 30 Gy. Jun was expressed increasingly with time until 5 or 6 hours after irradiation of $^{60}$Co in doses of 1 Gy and 10 Gy. After irradiation of $^{60}$Co in dose between 20 Gr and 100 Gy, the expression of Jun was however increased to peak in 2 hours and decreased thereafter. p53 gene in this study also seemed to be expressed near the threshold levels in 1 hour after irradiation of $^{60}$Co in dose less than 1 Gy and was expressed in maximum at 6 hours after irradiation of $^{60}$Co in dose of 1 Gy, p53 was expressed increasingly with time until 5 or 6 hours after irradiation of $^{60}$Co in dose between 1 Gy and 40 Gy. After irradiation of $^{60}$Co in doses of 50 Gy and 100 Gy, the expression of p53 was however increased to peak in 2 hours and decreased thereafter. The expression of Jun and p53 genes was not correlative in the brain tissue from rats. It seemed to be very important for the establishment of the optimum conditions for the animal studies relevant to the responses of genes inducible on DNA damage to ionizing radiation in mammalian cells. But there are many limitations to the animal studies such as the ununiform patterns of gene expression from the tissue because of its complex compositions. It is necessary to overcome the limitations for development of in situ Northern analysis.

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In Vitro Intrinsic Radiosensitivity Of Human Squamous Cell Carcinoma in Primary Culture (인체 상피 세포암의 일차 배양을 이용한 방사선 민감도 측정)

  • Choi Eun Kyung;Yang Kwang Mo;Yi Byong Yong;Chang Hyesook;Kim Sang-Yoon;Nam Joo-Hyun;Yu Eunsil;Lee Inchul
    • Radiation Oncology Journal
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    • v.12 no.1
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    • pp.27-31
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    • 1994
  • There are a number of reports suggesting that there may be a correlation between the clinical response to radiotherapy in various tumors and the clonogenic survival of cell lines derived from these tumors following exposure to 2 Gy(SF2). Authors conducted this study to determine SF2 for cells in primary culture from surgical specimens. The tumor tissues with squamous cell carcinoma of uterine cervix and head and neck were obtained. The tumor tissues were disaggregated to single cells by incubating with collagenase type w for 2 hours with constant stirring. Single cell suspensions were inoculated in four 24-well plates precoated with cell adhesive matrix. After 24 hours of incubation at 37$ ^{\circ}C $, rows of four wells were then irradiated, consisting of control set and five other sets each receiving doses of 1,2,3,4, and 6 Gy. After incubation for a total of 13 days, the cultures were stained with crystal violet and survival at each dose was determined by quantitative image analysis system, To determine whether cell growth was of epithelial origin, immunocytochemical staining with a mixture of cytokeratin and epithelial monoclonal antibodies were performed on cell cultures. During the period of this study, we received 5 squamous cell carcinoma specimens of head and neck and 20 of uterine cervical carcinoma. Of these, 15 yielded enough cells for radiosensitivity testing. This resulted an overall success rate of 60$ \% $. The mean SF2 value for 15 tumours was 0.55$\pm$0.17 ranging from 0.20 to 0.79. These results indicate that there is a broad range of sensitivities to radiation in same histologic type. So with a large patient population, we plan to determine whether a different SF2 value is associated with tumours that are controlled with radiotherapy than those that are not.

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Role of Radiotherapy for Squamous Cell Carcinoma of the External Auditory Canal and Middle Ear (외이도 및 중이 편평상피암의 방사선치료)

  • Kang, Hyun-Cheol;Wu, Hong-Gyun;Lee, Ji-Hye;Park, Charn-Il;Kim, Chong-Sun;Oh, Seung-Ha;Heo, Dae-Seog;Kim, Dong-Wan;Lee, Se-Hoon
    • Radiation Oncology Journal
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    • v.27 no.4
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    • pp.173-180
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    • 2009
  • Purpose: To investigate the role of radiotherapy for squamous cell carcinomas of the external auditory canal and middle ear. Materials and Methods: A series of 35 patients who were treated at a single institution from 1981 through 2007 were retrospectively analyzed. Thirteen patients were treated by radiotherapy alone; four by surgery only and 18 by a combination of surgery and radiotherapy. The total radiation dose ranged from 39~70 Gy (median, 66 Gy) in 13~35 fractions for radiotherapy alone and 44~70 Gy (median, 61.2 Gy) in 22~37 fractions for the combined therapy. Clinical end-points were the cause of specific survival (CSS) and local relapse-free survival (LRFS). The median follow-up time was 2.8 years (range, 0.2~14.6 years). Results: The 3-year CSS and LRFS rate was 80% and 63%, respectively. Based on a univariate analysis, performance status and residual disease after treatment had a significant impact on CSS; performance status and histologic grade for LRFS. Patients treated by radiotherapy alone had more residual disease following the course of treatment compared to patients treated with the combined therapy; 69% vs. 28%, respectively. Conclusion: Our results suggest that radiation alone was not an inferior treatment modality for CSS compared to the combined therapy for squamous cell carcinoma of the external auditory canal and middle ear. However, local failure after radiotherapy is the main issue that will require further improvement to gain optimal local control.

The Evaluation of Usefulness of Wide Beam Reconstruction Method on Segmental Perfusion and Regional Wall Motion in Myocardial Perfusion SPECT (심근관류 SPECT의 분절별 관류 및 국소벽 운동에서 Wide Beam Reconstruction기법의 유용성 평가)

  • Seong, Yong-Joon;Kim, Tae-Yeob;Moon, Il-Sang;Cho, Seong-Wook;Woo, Jae-Ryong
    • The Korean Journal of Nuclear Medicine Technology
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    • v.15 no.1
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    • pp.51-57
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    • 2011
  • Purpose: The aim of this study is to identify clinical usefulness of Wide Beam Reconstruction (WBR) which is called Xpress.cardiac$^{TM}$ to confirm the agreement between segmental perfusion and regional wall motion in myocardium compared to conventional OSEM method. Materials and Methods: Subjects were separated two groups. First group was composed of 20 normal control group. Second group was composed of 10 patients (abnormal group) who had coronary artery disease. Subjects underwent myocardial perfusion SPECT ($^{201}Tl$ rest and $^{99m}Tc$-MIBI stress). Image acquisition and reconstruction were that rest stage was each step per 30, 15 seconds and stress stage was each step per 25, 13 seconds, OSEM and WBR methods were applied. Segmental perfusion and regional wall motion were applied 20-segment model of QPS, QGS algorithm in AutoQuant. Status of perfusion was composed of 5 point scoring system (0=normal, 1=mild, 2=moderate, 3=severe hypokinesia, 4=dyskinesia). Status of regional wall motion was also composed of 5 point scoring (0=normal, 1=mild, 2=moderate, 3=severe hypokinesia, 4=dyskinesia). We evaluated the agreement between conventional OSEM and WBR through automatic quantification value. Results: The agreement of rest segmental perfusion between conventional OSEM and WBR in normal patients was 99% (396/400, k=0.662, p<0.0001) and one of rest regional wall motion was 83.8% (335/400, k=0.283), the agreement of stress segmental perfusion was 95.8%(383/400, k=0.656), one of stress regional wall motion was 87.3% (349/400, k=0.390). The match rate of rest segmental perfusion in abnormal patients was 83% (166/200, k=0.605, p<0.0001) and one of rest regional wall motion was 55.5% (111/200, k=0.385), the agreement of stress segmental perfusion was 79.5% (159/200, k=0.682), one of stress regional wall motion was 63.5% (127/200, k=0.486). Conclusion: Compared to conventional OSEM, WBR method had a good agreement of segmental perfusion in myocardium in normal and abnormal groups. However regional wall motion showed meaningful low agreement. Although WBR offers high resolution and contrast ratio, it is not useful method for gated myocardial perfusion SPECT.

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The Effect of Aroma Therapy on Lower Extremity Edema of Terminal Cancer Patients: A Controlled Trial (아로마 요법이 말기 암 환자의 하지부종에 미치는 영향 - 대조군 연구)

  • Kim, Sung-Ah;Kim, Sung-Ju;Chung, Ju-Hye;Lee, Soo-Young;Han, Myung-Suk;Oh, Seon-Hee;Kim, Se-Hong
    • Journal of Hospice and Palliative Care
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    • v.12 no.3
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    • pp.139-146
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    • 2009
  • This study was designed to examine the effect of aroma massage therapy on lower extremity edema of terminal cancer patients. Methods: A total of thirty-six terminal cancer patients with lower extremity edema were divided into two groups: the aroma massage group received massage with blending oil which was applied from toes to 10 cm above the knee of the subject for 15 to 20 minutes in each turn, while the control group received sham aroma massage (applied with carrier oil only). The circumferences of the fore-foot, ankle and calf were measured before massage and 30 minutes, 2 hours, and 12 hours after massage. The blood pressure, pulse and body temperature were also measured to find the change of subject's physiologic conditions. Results: There were no significant differences in blood pressure, heart rate, body temperature and lower extremity circumferences between two groups. However, edema at each site was slightly improved in the treatment group after the aroma massage therapy, compared to baseline data (P<0.05). In addition, the reduction of lower extremity circumference was maximal at 2 hours in foot, 30 min in right ankle and 12 hours in right calf after aroma massage therapy (P<0.05). Conclusion: Our results suggest that aroma massage therapy is not effective on the lower extremity edema of terminal cancer patients.

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Simultaneous HPLC Determination of Marker Compounds for the Standardization of Hedyotis diffusa (백운풀의 지표성분 설정 및 품질표준화를 위한 정량 분석법)

  • Bang, Han-Yeol;Yang, Eun-Ju;Kim, Jeong-Ah;Song, Kyung-Sik
    • Journal of Life Science
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    • v.23 no.8
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    • pp.1025-1031
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    • 2013
  • From a 95% ethanolic extract of H. diffusa, four marker compounds (HD1~HD4) were isolated, which were relatively unique and exist in comparably high contents. The structures of marker compounds were identified as digitolutein (1), 2-hydroxy-3-methylanthraquinone (2), (E/Z)-6-O-p-coumaroyl scandoside methyl ester (4:1 mixture) (3), and (E/Z)-6-O-p-methoxycinnamoyl scandoside methyl ester (4:1 mixture) (4), respectively, on the basis of $^{13}C$ and $^1H$-NMR analyses. The calibration curves of marker compounds showed high linearity, as their correlation coefficient ($R^2$) were in the range of 0.9991~0.9999. In addition, the limit of detection (LOD) and the limit of quantification (LOQ) were $0.03{\sim}0.07{\mu}g/ml$ and $0.099{\sim}0.231{\mu}g/ml$, respectively. The intra-day/inter-day precision and accuracy were 0.23~2.00%/0.25~1.16% and 94.60~108.44%/94.73-110.23%, respectively. The optimal HPLC conditions for the simultaneous quantification of HD1~HD4 were as follows: stationary phase; Merck Chromolith RP-18e ($100{\times}4.6mm$, $5{\mu}m$), column temp.; room temperature, UV detection at 280 nm, flow rate; 2.0 ml/min, injection volume; $10{\mu}l$, mobile phase; start with the mixture of 80% solvent A ($H_2O$ containing 0.5% acetic acid) and 20% solvent B (methanol containing 0.5% acetic acid) and gradually decrease solvent A to 40% in 9 min., then retain this condition to 18 min. Under the HPLC condition, the four marker compounds 1~4 were successfully separated without any interference of other constituents. The results obtained in this study are expected to be helpful for the development of nutraceutics and natural medicines and for the quality control of this plant.

Effect of Sugar Kind Added in Tris-buffer on Acrosome Damage of Post-thaw Spermatozoa in Canine (Tris-buffer에 첨가되는 당의 종류가 동결.융해정자의 첨체 손상에 미치는 영향)

  • 유대중;공일근
    • Journal of Embryo Transfer
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    • v.18 no.2
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    • pp.91-96
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    • 2003
  • The aim of this study was conducted to evaluate the effect of sugar kinds and combination of various sugars on acrosome damage of post-thaw spermatozoa in canine. The extender used in this study was Tris-citric acid extender (Tris-buffer) supplemented with 20% Egg-yolk, 8% glycerol, 1% Equex STM paste, and 70 mM sugars such as monosaccharide (fructose and xylose) and disaccharide(trehalose). To evaluate of sugar combination, the sugars supplemented in Tris-buffer were combined such as control (fructose, xylose, trehalose), two combinations (Fru+Tre, Fru+Xyl, Tre+Xyl) and three combinations (Fru+Tre+Xyl). The acrosome damage rate of post-thaw spermatozoa in Eosin B & Fast Green stain in Fruc+Tre was higher than those in fructose, trehalose, xylose, Fruc+Xyl, Tre+Xyl, Fruc+Tre+Xyl (83.0$\pm$5.6 vs. 82.3$\pm$3.1%, 81.7$\pm$2.1%, 72.0$\pm$2.0%; 80.3$\pm$4.5%, 76.7$\pm$3.8%, 81.0$\pm$5.6). The motility after CASA analysis in Fru+Tre was higher than those in Fru+Tre+Xyl, Tre+Xyl, Fru+Xyl, Xylose, Trehalose, Fructose(79$\pm$6 vs 75$\pm$3, 74$\pm$8, 71$\pm$11, 70$\pm$4, 66$\pm$15, 63$\pm$ 12%). However, the progressive motility after CASA analysis in Fru+Tre group was higher than those in Fru+Tre+Xyl, Tre+Xyl, Fru+Xyl, Xylose, Trehalose, Fructose (67$\pm$7, 64$\pm$3, 62$\pm$6, 61$\pm$8, 60$\pm$2, 57$\pm$13, 53$\pm$10%). The results indicated that the acrosome damage & progressive motility of post-thaw spermatozoa in 70 mM Fruc+Tre (two combination) following Eosin B & Fast Green stain and CASA analysis.

Development of Parthenotes Produced by Various Treatments in Bovine (활성화 처리에 따른 소 단위발생란의 발달)

  • 이성림;강태영;유재규;여현진;김세나
    • Journal of Embryo Transfer
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    • v.16 no.2
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    • pp.107-115
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    • 2001
  • Development of effective activation protocols is of great importance for improving the success of cloning and subsequent transgenic. Three methods for oocyte activation, including 5$\mu$M ionomycin (5 min) alone, ionomycin + 1.9 mM 6-dimetylaminopurine (DMAP, 3 hrs) and ionomycin + 10 $\mu\textrm{g}$/ml cycloheximide (CHX, 3 hrs) were compared for their effects of pronuclei (PN) formation, development, developmental velocity and ploidy of parthenotes to IVF control in bovine. In group of ionomycin + DMAP, the oocytes having more 3PN were significantly (P<0.05) higher than in groups of ionomycin alone and of ionomycin + CHX (45.5% vs. 0 and 0%, respectively). Activation with the ionomycin alone, ionomycin + DMAP and ionomycin + CHX resulted in cleavage rates of 30, 85.5 and 57.9%, respectively. The blastocysts rate of parthenotes activated by ionomycin + DMAP treatment was significantly higher (12.3%. p<0.05) than those of other treated groups. Chromosome analysis shows that ionomycin + DMAP treatment greatly enhances the incidence of chromosomal abnormality of the parthenotes. From the results, we may conclude that DMAP treatment to the oocytes accelerates developmental velocity resulting in both the higher incidence of chromosome abnormality and of PN formation, and strongly suggest that CHX combined with ionomycin is better than DMAP for the purpose of successful nuclear transplantation. Developmental velocity of parthenotes activated by ionomycin + DMAP treatment was significantly (P<0.05) faster than others.

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