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S H Cho

Publications and source records attributed to S H Cho.

At least 145 records · Page 8Linked to original sources
PubMed1998

A new member of alpha 1-adrenoceptor-coupled G alpha h (transglutaminase II) family in pig heart: purification and characterization.

We previously reported an identification of a 77-kDa GTP-binding protein that co-purified with the alpha 1-adrenoceptor following ternary complex formation. In the present paper, we report on the purification and characterization of this GTP-binding protein (termed G alpha h5) isolated from pig heart membranes. After solubilization of pig heart membranes with NaCl, G alpha h5 was purified by sequential chromatographies using DEAE-Cellulose, Q-Sepharose, and GTP-agarose columns. The protein displayed high-affinity GTP gamma S binding which is Mg(2+)-dependent and saturable. The relative order of affinity of nucleotide binding by G alpha h5 was GTP > GDP > ITP >> ATP > or = adenyl-5'-yl imidodiphosphate, which was similar to that observed for other heterotrimeric G-proteins involved in receptor signaling. Moreover, the G alpha h5 demonstrated transglutaminase (TGase) activity that was blocked either by EGTA or GTP gamma S. In support of these observations, the G alpha h5 was recognized by a specific antibody to G alpha h7 or TGase II, indicating a homology with G alpha h (TGase II) family. These results demonstrate that 77-kDa G alpha h5 from pig heart is an alpha 1-adrenoceptor-coupled G alpha h (TGase II) family which has species-specificity in molecular mass.

Animals↗
PubMed1998

Cloning and characterization of cDNAs coding for heavy and light chains of agglutinating monoclonal antibody (HAG12islrh) specific for human red blood cells.

Complementary DNAs encoding the heavy and light chains of the Fab fragment of mouse agglutinating monoclonal antibody against human red blood cells were cloned by polymerase chain reaction and their nucleotide sequences were determined. The sequence analysis showed that the variable regions of the heavy and light chains were the members of mouse heavy-chain subgroup IIa and kappa light-chain subgroup I, respectively. A few unusual amino acids in the constant regions of the heavy chain were also recognized.

Aged↗
PubMed1998

Cloning of a cDNA encoding phospholipase D from Pimpinella brachycarpa.

Phospholipase D (PLD, EC 3.1.4.4) has been known to be related to various cellular processes in plants. To gain an understanding of the property of the enzyme in Pimpinella brachycarpa, the cDNA of the enzyme was isolated by PCR with degenerate primers, cDNA library screening, and 5' RACE. The full-length PLD cDNA is 2859 bp long and contains an open reading frame of 2424 bp coding for a polypeptide of 808 amino acids. The deduced enzyme has a calculated molecular mass of 91.7 kDa and pI of 5.86. The percent identity and similarity values of P. brachycarpa PLD with those of other PLDs in plants are 70 approximately 78 and 84 approximately 95, respectively. It was identified that PLD from P. brachycarpa has HQKIVVVD and HAKMMIVD sequences which were homologous with a duplicated HXKXXXXD motif that has been conserved in PLDs from plants, animals, and yeast. Based on the analysis of amino acid similarity, it is believed that PLD from P. brachycarpa is an alpha form which is distinct from PLD beta reported recently. The N-terminus is homologous to the C2 domain which is present in a number of different proteins involved in signal transduction and membrane trafficking in animals. Southern and northern blot analyses indicated that PLD was expressed from one copy of PLD gene in the genome of P. brachycarpa.

Amino Acid Sequence↗
PubMed1998

Tepidopterin, 1-O-(L-threo-biopterin-2'-yl)-beta-N-acetylglucosamine from Chlorobium tepidum.

A novel pterin compound, designated as tepidopterin, was detected from a thermophilic photosynthetic green sulphur bacterium, Chlorobium tepidum. The amount of tepidopterin inside the cell was estimated to be 2-5 micromol g(-1) dry weight of cell. This compound was purified through a high performance liquid chromatography using preparative DeltaPak C18 column. This compound was characterized by chromatographic behavior and by absorption and fluorescence properties. Its structure was determined to be 1-O-(L-threo-biopterin-2'-yl)-beta-N-acetylglucosamine by 1D- and 2D-NMR spectroscopy, mass spectrometry and CD. The relative amount of tetrahydrotepidopterin was estimated to be 96.7% inside the cell, that of dihydrotepidopterin 2.9%, and that of fully oxidized tepidopterin 0.4%. The amount of tepidopterin within the cell increased continuously until the beginning of the stationary phase of the cell growth.

Acetylglucosamine↗
PubMed1998

The Bcl-2 gene family and apoptosis.

Apoptosis, or programmed cell death, is an essential process for normal embryonic development, maintaining homeostasis in adult tissues, and suppressing carcinogenesis. The bcl-2 protein, discovered in association with follicular lymphoma, plays a prominent role in controlling apoptosis and enhancing cell survival in response to diverse apoptotic stimuli. The evolutionarily conserved bcl-2 protein is now recognized as being a member of a family of related proteins which can be categorized as death agonists or death antagonists. Progress in defining the role of bcl-2 and its family members in regulating apoptosis is rapidly advancing. This review describes, in detail, current bcl-2 family members and the possible mechanisms of function which allow the bcl-2 family of proteins to either promote or suppress cell death.

Animals↗
PubMed1998

Tibial bone defects treated by internal bone transport using the Ilizarov method.

We reviewed 27 cases of tibial bone defects treated by internal bone transport using the Ilizarov method. The causes of the bone defects were open fractures in 14 segments and infected non-unions in 13. The average length of the defects was 8.3 cm (range, 3-20 cm). There were 21 one-level tibial transports, 3 two-level tibial transports, 1 one-level tibial transport with fibular transport, and 2 fibular transports. At the docking site, 25 segments underwent bone grafting. Eleven of the 25 were Papineau-type open cancellous bone grafts. Acute shortening or docking was performed in 10 segments. Bone union was obtained in every instance. The average time of external fixation was 8 months and the average time to union was 7.1 months. Bone grafting at the docking site is recommended in order to shorten the duration of treatment and to prevent refracture and non-union.

Adolescent↗
PubMed1998

Smads are the central component in transforming growth factor-beta signaling.

Until recently, little was known about how transforming growth factor (TGF)-beta signals are transduced to the nucleus. With the discovery of the Smad proteins initially in Drosophila and C. elegans, the unraveling of the pathway has begun. Nine different vertebrate members also have been reported, indicating that Smads are a conserved component of the TGF-beta pathway. Currently, there are three functional classes of Smads. Class I Smads are phosphorylated by TGF-beta receptors and move to the nucleus. The Class II Smads function with Class I Smads, while Class III Smads antagonize the function of Class I Smads. New evidence shows that Smads bind specific DNA sequences and induce transcription of downstream target genes, thus placing the Smads at the center of the TGF-beta signaling pathway.

Animals↗
PubMed1998

Concomitant lichen scrofulosorum and erythema induratum.

We describe a patient in whom two tuberculids, lichen scrofulosorum, and erythema induratum occurred simultaneously. The clinical and histopathologic features were characteristic and a Mantoux test showed a positive reaction. There was no extracutaneous focus of tuberculosis. Polymerase chain reaction for mycobacteria in the skin lesions was negative, but her lesions responded rapidly to antituberculous chemotherapy.

Adult↗
PubMed1998

Drainage versus nondrainage in simultaneous bilateral total hip arthroplasties.

A prospective study of 48 patients (96 hips) who had undergone primary simultaneous bilateral total hip arthroplasty was conducted to assess the effect of postoperative suction drainage on wound healing and infection. A suction drain was placed by randomization of the drained versus undrained side. The same surgical technique was used in all total hip arthroplasty wounds. Statistical analysis of the results showed significant differences with respect to drainage from the wound, soaked dressings requiring reinforcements, ecchymosis, and erythema about the wound in the group without drainage. There was no specific correlation between the incidence of wound complications and infection after total hip arthroplasty and the use or nonuse of closed-suction drainage. The hip score and range of motion of the hip were unaffected by the use or nonuse of the drains. The cost of 1 set of hemovac drains is $135 and the cost for 4-5 dressings and bed sheet changes is about $50. Although the hemovac is more expensive, the authors recommend the routine use of suction drains for wounds after primary total hip arthroplasty to reduce drainage, soaked dressings requiring reinforcement, ecchymosis and erythema around the wound, and psychological impact on the patient's fear of bleeding.

Adult↗
PubMed1998

Purification and characterization of the tyrosinase isozymes of pine needles.

Three tyrosinase isozymes were purified to electrophoretic homogeneity from pine needles. The molecular weight of the three isozymes (P1, P2 and P3) were approximately 65,000, 50,000 and 45,000, and the pI values were 6.2, 5.9 and 5.3, respectively. The three isozymes have a number of common properties. These include amino acid composition, substrate specificity, response to inhibition. The amino acid compositions of the three isozymes showed the characteristic high contents of glycine, serine and glutamic acid residues. The three isozymes exhibited high substrate specificity towards pyrogallol. The K(m) values of the three isozymes for L-DOPA ranged from 8.7 to 10 mM. L-ascorbic acid and beta -mercaptoethanol, glutathione and sodium diethyldithiocarbamate notably inhibited the enzymatic activities.

Amino Acids↗
PubMed1998

Treatment of antecubital pterygium in the nail-patella syndrome.

Antecubital pterygium is rare in the nail-patella syndrome but common in the multiple pterygium syndrome and aplasia of the trochlea. It is known that there is the rebound phenomenon after treatment of congenital joint contracture. We describe the poor functional results due to rapid recurrence of the flexion contracture treated with the Ilizarov method for an antecubital pterygium in the nail-patella syndrome.

Child↗
PubMed1998

The Drosophila gene Medea demonstrates the requirement for different classes of Smads in dpp signaling.

Signals from transforming growth factor-beta (TGF-beta) ligands are transmitted within the cell by members of the Smad family, which can be grouped into three classes based on sequence similarities. Our previous identification of both class I and II Smads functioning in a single pathway in C. elegans, raised the issue of whether the requirement for Smads derived from different classes is a general feature of TGF-beta signaling. We report here the identification of a new Drosophila class II Smad, Medea, a close homolog of the human tumor-suppressor gene DPC4. Embryos from germline clones of both Medea and Mad (a class I Smad) are ventralized, as are embryos null for the TGF-beta-like ligand decapentaplegic (dpp). Loss of Medea also blocks dpp signaling during later development, suggesting that Medea, like Mad, is universally required for dpp signaling. Furthermore, we show that the necessity for these two closely related, non-redundant Smads, is due to their different signaling properties - upon activation of the Dpp pathway, Mad is required to actively translocate Medea into the nucleus. These results provide a paradigm for, and distinguish between, the requirement for class I and II Smads in Dpp/BMP signaling.

Amino Acid Sequence↗
PubMed1998

Effects of soluble dietary fibers on lipid metabolism and activities of intestinal disaccharidases in rats.

The present study was aimed to investigate the effects of indigestible dextrin and polydextrose, soluble dietary fibers with low molecular weight, on lipid metabolism and disaccharidase activities of intestinal mucosa in rats fed a high sucrose diet. Their effects were compared with those of well-known soluble fibers, pectin, and guar gum, and also with an insoluble fiber, cellulose. Dietary fibers added to diets at the 5% (w/w) level were alpha-cellulose, pectin, guar gum, indigestible dextrin, and polydextrose. Male Sprague-Dawley rats were given free access to test diets for 6 weeks. Body weight gain was the lowest in rats fed guar gum, the highest in rats fed cellulose, and in-between in rats fed other diets. Although guar gum, pectin, and indigestible feeding dextrin had lower plasma lipid values than cellulose feeding did, the differences were statistically insignificant. Liver triglyceride of the guar gum-fed group was about a third that of the cellulose-fed group, but although those of rats fed polydextrose, indigestible dextrin, and pectin were lower than that of cellulose, the differences were insignificant. Liver cholesterol and phospholipid concentrations were similar among groups. Daily fecal excretion of total lipid, cholesterol, and bile acids were highest in rats fed guar gum, followed by pectin-fed and cellulose-fed rats, and the lowest in rats fed indigestible dextrin and polydextrose. Jejunal sucrase activity was low in the order of guar-gum, polydextrose, indigestible dextrin, pectin, and cellulose. The results indicate that the hypolipidemic effect of soluble dietary fibers would be lessened with reduction in molecular weight, but that the lower sucrase activity by soluble fibers with low molecular weight might be beneficial for hypoglycemic effect.

Animals↗
PubMed1998

Female sex hormones and body mass in adolescent and postmenopausal Korean women.

A cross-sectional study was conducted to evaluate the relationship between body mass and serum level of female sex hormones among 153 adolescent girls, and 153 postmenopausal women in Korea. Information on lifestyles, and both menstrual and reproductive factors was collected by personal interview. Serum total estradiol (E2), progesterone (Pg), and sex hormone binding globulin (SHBG) concentrations were measured by radioimmunoassay. Multiple linear regression analysis was used to determine whether the hormonal levels would be affected by the obesity indices. Body weight and body mass index (BMI) were inversely related to SHBG level in both premenopausal (p<0.005) and postmenopausal women (p<0.005) after adjusting for age. E2 levels during any phase in premenopausal girls were not related to BMI, whereas heavier girls had significantly higher levels of late luteal-phase Pg (p<0.05). Taller postmenopausal women had lower E2 levels (p<0.05). Results on the association between SHBG and BMI are consistent with previous results in Caucasian women, and might suggest the potential role of bioavailable estradiol in breast carcinogenesis in pre- and post-menopausal women. The finding that progesterone might be related to body mass in premenopausal women should be pursued in further studies.

Adolescent↗
PubMed1998

Fanconi anemia screening by diepoxybutane and mitomicin C tests in Korean children with bone marrow failure syndromes.

Fanconi anemia (FA) is an autosomal recessive disorder of progressive bone marrow failure in patients with congenital malformations. FA is different from acquired aplastic anemia (AA) in terms of the natural course and treatment options. As the frequency of FA is unknown in Korea, we conducted screening tests using DNA clastogenic agents, diepoxybutane (DEB) and mitomicin C (MMC) in southwestern Korea. Forty-three children with AA or other bone marrow failure syndromes and siblings of known FA were evaluated. Six patients with AA (6/24=25.0%) and a 2-month-old patient with myelodysplastic syndrome were found to have increased chromosomal breakage to both DEB and MMC, confirming the diagnosis of FA. No overlap in chromosomal breakage to both agents was found between the FA group and non-FA group. The frequency of FA in this study, much higher than those of previous studies in Korea which did not incorporate the above tests, was similar to that of other countries. DEB and MMC tests were readily feasible and useful in screening FA in patients with AA as well as other bone marrow failure syndromes. A nation-wide screening and registry for FA should be initiated since FA requires different therapeutic and management options from idiopathic AA.

Adolescent↗
PubMed1998

Drainage versus nondrainage in simultaneous bilateral total knee arthroplasties.

A prospective study of 69 patients (138 knees) who had a primary simultaneous bilateral total knee replacement was conducted to assess the effect of postoperative suction drainage on wound healing and infection. A suction drain was placed by randomization of side for the drained versus nondrained side. The same operative technique was used in all wounds of total knee arthroplasty. The knees that had no drains had a higher incidence of drainage from the wound, had soaked dressings requiring dressing reinforcements, and had more ecchymosis and erythema around the wound. However, the final results regarding quadriceps strength, range of motion, and wound complications were not affected significantly by nonuse of closed suction drainage. Although the incidence of infection in the two groups is not statistically different, the development of infection in two knees in which drains were not used suggests that suction drainage may reduce deep infection.

Adult↗