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81.
The present study was undertaken to elucidate the mechanism of nuclear membrane dissolution (NMD) in puromycin-treated mouse oocytes. Treatment of germinal vesicle breakdown (GVBD) oocytes with puromycin (50 micrograms/ml) induced chromosome decondensation with formation of a polar body; these are designated nuclear membrane (NM) oocytes. After withdrawal of puromycin, NM oocytes underwent NMD (approximately 70%) during a 12-h culture period. Either dibutyryl cyclic AMP (dbcAMP, 25-100 micrograms/ml) or isobutylmethylxanthine (IBMX, 0.1-1.0 mM) inhibited the process of NMD in a dose-dependent manner, suggesting the involvement of cAMP in the process of NMD. To determine which protein(s) participated in the transition from interphase to metaphase II during NMD, NM oocytes were labeled with [35S]methionine, and one- and two-dimensional gel electrophoresis were performed. Although the synthesis of stage-specific proteins during NMD was not found, two specific proteins of Mr 27,000 and 46,000, which were synthesized at interphase following removal of puromycin, were modified during NMD. Phosphatase treatment and 32PO4-labeling experiments indicated that phosphorylation was responsible for these modifications, which were inhibited by either dbcAMP or IBMX. Therefore, it appears that phosphorylation of specific proteins may play an important role in the transition from interphase to metaphase II. 相似文献
82.
83.
Eunkyung Kim Ji‐Yun Hwang Eun‐Kyung Woo Sung‐Soo Kim Sangmee Ahn Jo Inho Jo 《Obesity (Silver Spring, Md.)》2005,13(9):1510-1514
Objectives: To establish BMI percentiles and cutoffs for underweight, overweight, and obesity in South Korean schoolgirls. Research Methods and Procedures: A total of 1229 South Korean schoolgirls aged 8 to 18 years were randomly selected to complete a self‐administered questionnaire. BMI charts and cutoffs were constructed after analyzing data from 1107 subjects. Percentile curves were established by the modified LMS method. Results: The percentiles for underweight, overweight, and obesity corresponding to BMI of 18.5, 23.0, and 25.0 kg/m2 at age 18 were the 13.0th percentile, the 77.8th percentile, and the 91.2nd percentile, respectively. The corresponding prevalences of underweight, overweight, and obesity were 12.1, 12.5, and 9.8%, respectively. Discussion: We established for the first time, to our knowledge, new BMI cutoffs for ages 8 to 18 that corresponded to BMIs of 18.5, 23.0, and 25.0 kg/m2 for Asian adults designated by the International Obesity Task Force. These newly established BMI cutoffs might help to estimate the prevalence of overweight and obesity in Asian children. 相似文献
84.
Ji Eun Kim Eun Jeong Kim Won Jong Rhee Tai Hyun Park 《Biotechnology and Bioprocess Engineering》2005,10(4):353-356
The effect of silkworm hemolymph on the expression of recombinant protein inEscherichia coli was investigated. The addition of silkworm hemolymph to the culture medium increased the production of recombinant β-galactosidase
inE. coli. The production was dependent on the concentration of the added silkworm hemolymph, which increased 2-, 5-, and 8-fold in
media supplemented with 1,3, and 5% silkworm hemolymph, respectively. To identify the effective component, the silkworm hemolymph
was fractionated by gel filtration column chromatography. A fraction, with a molecular weight of about 30 K was identified
as the effective component. 相似文献
85.
Se-Kwon Kim Pyo-Jam Park Won-Kyo Jung Hee-Guk Byun Eresha Mendis Young-In Cho 《Carbohydrate polymers》2005,60(4):483-487
Chitooligosaccharides (COSs) were successfully prepared using an ultrafiltration membrane bioreactor system, and named as COS-I (10–5 kDa), COS-II (5–3 kDa), COS-III (3–1 kDa), and COS-IV (below 1 kDa), respectively. In addition, their phosphorylated derivatives were prepared by a P2O5 in methanesulfonic acid solution, and inhibitory activity on the formation of insoluble calcium phosphate of phosphorylated chitooligosaccharides. Phosphorylated COS-IV exhibited the highest inhibitory activity of calcium phosphate precipitation among tested chitooligosaccharides. Its inhibitory activity, especially at the concentration more than 4 mg/ml, was similar to that of CPP, which is widely used as a calcium fortifying agent increasing calcium absorbability. Therefore, phosphorylated chitooligosaccharides may be potential inhibitors of calcium phosphate precipitation. 相似文献
86.
Introduction of tyramide signal amplification (TSA) to pre-embedding nanogold-silver staining at the electron microscopic level. 总被引:3,自引:0,他引:3
Seung-won Lee Song Eun Lee Seong Hyuk Ko Eun Kyoung Hong Kwang Il Nam Kei-ichiro Nakamura Shuhei Imayama Yeong-Joon Park Kyu Youn Ahn Choon Sang Bae Baik Yoon Kim Sung Sik Park 《The journal of histochemistry and cytochemistry》2005,53(2):249-252
The tyramide signal amplification (TSA) technique has been shown to detect scarce tissue antigens in light and electron microscopy. In this study we applied the TSA technique at the electron microscopic level to pre-embedding immunocytochemistry. This protocol was compared to the non-amplified protocol. With the TSA protocol, the labeling of GM130, a cis-Golgi matrix protein, was tested in a cell line and found to be highly sensitive and more enhanced than that with the simple protocol. Moreover, the gold particles were well localized to the cis-side of the Golgi apparatus in both the TSA and the simple protocol. 相似文献
87.
88.
Chul-Min Kim Ying-Hua Yi Do-Hyeon Yu Mi-Jin Lee Mae-Rim Cho Atul R. Desai Smriti Shringi Terry A. Klein Heung-Chul Kim Jin-Won Song Luck-Ju Baek Sung-Tae Chong Monica L. O'Guinn John S. Lee In-Yong Lee Jin-Ho Park Janet Foley Joon-Seok Chae 《Applied microbiology》2006,72(9):5766-5776
In order to investigate the prevalence of tick-borne infectious agents among ticks, ticks comprising five species from two genera (Hemaphysalis spp. and Ixodes spp.) were screened using molecular techniques. Ticks (3,135) were collected from small wild-caught mammals or by dragging/flagging in the Republic of Korea (ROK) and were pooled into a total of 1,638 samples (1 to 27 ticks per pool). From the 1,638 tick samples, species-specific fragments of Anaplasma phagocytophilum (1 sample), Anaplasma platys (52 samples), Ehrlichia chaffeensis (29 samples), Ehrlichia ewingii (2 samples), Ehrlichia canis (18 samples), and Rickettsia rickettsii (28 samples) were amplified by PCR assay. Twenty-one pooled and individual tick samples had mixed infections of two (15 samples) or three (6 samples) pathogens. In addition, 424 spleen samples from small captured mammals (389 rodents, 33 insectivores, and 2 weasels) were screened for selected zoonotic pathogens. Species-specific DNA fragments of A. phagocytophilum (110 samples), A. platys (68 samples), E. chaffeensis (8 samples), E. ewingii (26 samples), E. canis (51 samples), and Rickettsia sp. (22 samples) were amplified by PCR assay. One hundred thirty small mammals had single infections, while 4, 14, and 21 striped field mice (Apodemus agrarius) had mixed infections of four, three, and two pathogens, respectively. Phylogenetic analysis based on nucleotide sequence comparison also revealed that Korean strains of E. chaffeensis clustered closely with those from China and the United States, while the Rickettsia (rOmpA) sequences clustered within a clade together with a Chinese strain. These results suggest that these agents should be considered in differential diagnosis while examining cases of acute febrile illnesses in humans as well as animals in the ROK. 相似文献
89.
Y. J. Cho S. Y. Kim J. Kim E. K. Choe S. I. Kim H. J. Shin 《Biotechnology and Bioprocess Engineering》2006,11(3):230-234
In this study, we describe a one-step chemoenzymatic reaction for the production of natural blue pigments, in which the geniposide
from Gardenia extracts is transformed by glycosidases to genipin. Genipin is then allowed to react with amino acids, thereby
generating a natural blue pigment. The β-glycosidases, most notably isolase (a variant of β-glucanase), recombinant β-glucosidase,
Cellulase T, and amylases, were shown to hydrolyze geniposide to produce the desired pigments, whereas the α-glycosidases
did not. Among the 20 tested amino acids, glycine and tyrosine were associated with the highest dye production yields. The
optimal molar ratio of geniposide to glycine, two reactants relevant to pigment production, was unity. The natural blue pigments
produced in this study were used to dye cotton, silk, and wool. The color yields of the pigments were determined to be significantly
higher than those of other natural dyes. Furthermore, the color fastness properties of these dyes were fairly good, even in
the absence of mordant. 相似文献
90.
Sung-Jin Cho Dae-Hee Lee Hyuk-Jae Kwon Chi Hyun Ahn Soon Cheol Park Kil-Sang Shin 《Development genes and evolution》2006,216(6):353-351
An echiuroid species, Urechis unicinctus, was surveyed for Hox genes using polymerase chain reaction with homeobox-specific degenerate primers. We identified nine distinct homeodomain-containing gene fragments. These nine fragments were classified by comparative analysis. This analysis revealed that this echiuroid possessed at least three Hox genes from the anterior group, five from the central group, and one from the posterior group.Sung-Jin and Dae-Hee Lee contributed equally to this work.An erratum to this article can be found at 相似文献