[Epidemiologic study of muscular dystrophy at school age in Gifu city].
Explore the source record for details and available documents.
Adolescent↗
Biomedical subjects
S Yamada
Publications and source records attributed to S Yamada.
Japanese population DNA typing data for the loci LDLR, GYPA, HBGG, D7S8, and GC.
Population studies on the five loci LDLR, GYPA, HBGG, D7S8, and GC (PM loci) were carried out in a sample of 366 unrelated Japanese individuals living in Gifu Prefecture (central region of Japan) using the AmpliType PM PCR Amplification and Typing kit (Perkin Elmer). For all loci, no significant deviations from Hardy-Weinberg equilibrium could be found in our Japanese population sample. The combined mean exclusion chance and power of discrimination for the PM loci were 0.68 and 0.993, respectively. The Japanese and Chinese population data were similar for the all loci. The Japanese and Korean population data were similar for all loci other than D7S8. Significant differences were observed between the Japanese population data and the 16 other population data compared for 3 loci or more.
Asian People↗
[Analysis of induction of MDR1 gene expression by anticancer chemotherapy in bladder cancer].
Using a reverse transcriptase-polymerase chain reaction (RT-PCR)-based quantitative analysis method, we investigated MDR1 mRNA expression levels in 58 bladder cancer specimens to determine whether MDR1 gene expression was induced or enhanced in bladder cancers during chemotherapy. In bladder cancer specimens which were obtained from patients treated with anticancer drugs, significantly higher expression levels of MDR1 mRNA were observed than in those from patients not treated with any anticancer drugs (p = 0.0134, Mann-Whitney U test). From 14 patients who had bladder cancer, clinical specimens were obtained before and after neoadjuvant intra-arterial chemotherapy. The expression levels of MDR1 mRNA were significantly higher in the post-treatment specimens than in the pre-treatment specimens (p = 0.0298, Wilcoxon signed-rank test). Of these 14 patients, 7 patients exhibited increased levels of MDR1 mRNA expression after chemotherapy. In 6 patients, there were no changes in the MDR1 mRNA expression levels before and after chemotherapy. Only one patient exhibited decreased levels of MDR1 mRNA expression after chemotherapy. No significant correlations were observed, between MDR1 mRNA expression levels and effect of the chemotherapy determined microscopically, dosage of anticancer drugs, or patient outcome. In conclusion, this study indicates that MDR1 gene expression in bladder cancers is induced and enhanced during chemotherapy. This overexpression of the MDR1 gene may contribute to resistance to anticancer drugs after repeated chemotherapy.
ATP Binding Cassette Transporter, Subfamily B, Mem↗
[A case of liver metastases from leiomyosarcoma in the chest wall which was made resectable by chemoembolization].
We here report a recently experienced case in which TAE and intra-arterial infusion chemotherapy for treatment of liver metastases of leiomyosarcoma in the chest wall caused a shrinking of the metastasized focus, thus facilitating liver resection. Patient; a 38-year-old man Present History and Courses; Resection of leiomyosarcoma in his chest wall was done in May, 1994. However, a local recurrence was noted in September, 1995, and the tumor was removed. Then, he received systemic chemotherapy with CDDP (100 mg) and ADM (45 mg). Abdominal CT and ultrasonic examinations made in February, 1996 revealed liver metastases at S2,5,8. Angiography detected densely stained images of tumors at a number of sites along with S2,5,8. Since these were thought unresectable, TAE therapy with EPIR (30 mg) and lipiodol (4 ml) was attempted 3 times. Then, a reservoir for intra-hepatic arterial infusion was implanted in April, 1996 and EPIR at a dose of 30 mg (150 mg in total) was given through arterial infusion, resulting in tumor disappearance at S5,8 but further growth of the tumor metastasizes at S2. Therefore, a resection of the left lateral segment of liver was done August 23. Though he was discharged in October, metastasis was found in the thoracic spine in December. Thus, he underwent resection of the vertebral arch including the tumor.
Adult↗
[Clinical efficacy of post-TUR prophylactic chemotherapy for superficial bladder cancer--the result of co-operative prospective randomized trial].
We have performed a prospective randomized clinical trial of post-operative prophylactic therapy for superficial bladder cancer since October in 1991. The criteria were as follows; age < or = 80 y.o., Ta/T1, TCC G1/G2, without CIS lesion and resectable cancer by TUR. The therapeutic arm was divided into three as follows: arm A intracystic instillation with Epirubicin; arm B: oral administration with 5-FU; arm C: combination of arm A and arm B. The number of registered patients were 20 in arm A, 18 in arm B, and 18 in arm C. The patient characteristics in every group were not significantly different. The prophylactic efficacy of arm A was superior to that in the other two groups.
Administration, Intravesical↗
Plasma collagen-binding vitronectin activated by heparin and dextran sulfate in chronic liver disease.
Plasma collagen-binding vitronectin was assayed in 62 patients with chronic liver disease and 14 healthy control subjects. It was measured by an enzyme immunoassay using type I collagen and monoclonal antibody to vitronectin before and after treatment with heparin or dextran sulfate in vitro. The pretreatment level of plasma collagen-binding vitronectin (mean +/- S.E.M.) was 5.5 +/- 0.5 micrograms/ml in the controls, 8.2 +/- 0.3 micrograms/ml in chronic persistent hepatitis, 8.3 +/- 0.7 micrograms/ml in chronic active hepatitis, 7.9 +/- 0.7 micrograms/ml in liver cirrhosis, and 8.2 +/- 0.5 micrograms/ml in hepatocellular carcinoma with cirrhosis. After treatment with heparin, the percent collagen-binding vitronectin to total vitronectin was 20.6 +/- 2.0% in the controls, 24.7 +/- 4.1% in chronic persistent hepatitis, 28.6 +/- 2.5% in chronic active hepatitis, 42.6 +/- 4.5% in liver cirrhosis, and 31.8 +/- 2.3% in hepatocellular carcinoma. All percents were significantly increased compared to the pretreatment percent. The same pattern was also found after dextran sulfate treatment. Compared to that in the pretreatment state, the collagen-binding vitronectin after these treatments was more closely correlated with the serum levels of 7S collagen and hyaluronic acid. These results suggest that the collagen-binding activity of vitronectin may play an important role in the progression of liver disease and/or fibrosis through its activation with some glycosaminoglycans.
Adult↗
[Effects of combination chemoradiotherapy with daily low-dose CDDP for esophageal cancer--results of a randomized trial].
Between 1994 and 1996, 24 patients with esophageal carcinoma were entered in a randomized clinical trial comparing radiotherapy (RT) only (arm A) versus RT and a daily low dose of CDDP (5 mg/m2) (arm B). For arm B group, CDDP was injected within 30 min after irradiation. All patients were irradiated with a total dose of 60 Gy /30fr. at first, and some patients were boosted. An overall response rate of 75.0% (complete response rate of 25.0%) was observed in arm A and 91.7% (complete response rate of 16.7%) in arm B, respectively. The survival rate at 1 year was 23.8% in arm A and 40.0% in arm B. Median survival time was 7 months in arm A and 9 months in arm B. Toxicity was acceptable and no significant difference was noted between arm A and arm B.
Aged↗
Abnormality in plasma catecholamines and myocardial adrenoceptors in cardiomyopathic BIO 53.58 Syrian hamsters and improvement by metoprolol treatment.
The catecholaminergic neuronal activity and the densities of alpha-1 and beta adrenoceptors and angiotensin II receptors were simultaneously determined in BIO 53.58, a model of idiopathic dilated cardiomyopathy, and F1B control hamsters. Further, we examined the effect of repeated p.o. administration of metoprolol on these biochemical parameters. Compared with F1B control hamsters, there was a significant decrease in Bmax of specific binding of both (-)-[125I]iodocyanopindolol and [3H]prazosin with a marked elevation of plasma catecholamine (mainly norepinephrine and epinephrine) concentrations, in BIO 53.58 hamsters at 11 and 18 weeks of age (severe cardiomyopathic stage), but not at 5 weeks of age. On the other hand, the Bmax value of myocardial [125I]angiotensin II binding in BIO 53.58 hamsters was almost identical to that in F1B hamsters. These results suggest a development of down-regulation of myocardial beta and alpha-1 adrenoceptors because of an increased catecholaminergic neuronal activity with aging in BIO 53.58 hamsters. Repeated p.o. administration of a relatively low dose (1 mg/kg/day) of metoprolol for 7 weeks in 11-week-old BIO 53.58 hamsters caused a significant increase of myocardial (-)-[125I]iodocyanopindolol binding sites with a marked reduction in plasma catecholamine levels; this indicated a significant recovery to the F1B levels. The improvement of these biochemical parameters by metoprolol treatment was also accompanied by a significant decrease in the fibrosis in the heart in BIO 53.58 hamsters. These data suggest that catecholaminergic neurons and adrenoceptors play a part in the development of heart failure in idiopathic dilated cardiomyopathy. Consequently, the present study may provide a further pharmacological basis for the use of beta-1 adrenoceptor antagonists in patients with idiopathic dilated cardiomyopathy.
Adrenergic beta-Antagonists↗
[A case of rheumatoid pachymeningitis].
Here we present a 53-year-old woman with rheumatoid pachymeningitis. The subject had rheumatoid arthritis (RA) for 15 years. In April, 1996 she began to experience intermittent headaches. In September, her headaches became severe and continuous. In October, she suddenly developed ptosis of the left eye and diplopia. She also started to have dysphagia and she found it increasingly difficult to eat. She was admitted to our hospital on November 1, 1996. Neurological examinations revealed palsies of the left IIIrd, IVth, and VIth, and bilateral IXth, and Xth cranial nerves. Laboratory findings showed leukocytosis, elevated blood sedimentation rate, and positive CRP. Serum RA titer was positive (30x). The cerebrospinal fluid was normal and bacteriological examination was negative. T1-weighted MRI demonstrated hypertrophic cranial dura extending from the falx cerebri to tentorium cerebelli, which was enhanced markedly by Gd-DTPA. The dura adjacent to the cavernous sinus and the clivus were also thickened, which probably caused her cranial polyneuropathies. The dural biopsy showed massive infiltration of the inflammatory cells throughout the dura, proliferation of collagen fibers, and necrotic granuloma with neutrophilic infiltrations. Neither rheumatoid nodules, nor vasculitis were found. Despite the absence of rheumatoid nodules in the dural biopsy, the clinical features, pathologic specimens, and MRI findings of the thickened dura were most consistent with rheumatoid pachymeningitis. Administration of dexamethason ameliorated her headache on the 4th hospital day, and the cranial polyneuropathies completely disappeared on the 35th hospital day. The dural enhancement previously seen on the contrast T1-weighted MRI was diminished. Serum RA titer was also normalized (10x). Rheumatoid pachymeningitis is an extremely rare disease, and only 16 cases were reported in the literatures. Hypertrophic pachymeningitis should be considered as a diagnostic possibility in RA patients who have prolonged headache, and Gd-DTPA MRI is recommended to demonstrate the dural involvement.
Arthritis, Rheumatoid↗
Responses of peri-implant tissues to undisturbed plaque formation in dogs: clinical, radiographic, and microbiological findings.
The present investigation evaluated the clinical and microbiological effects of long-term undisturbed plaque formation on peri-implant tissues. Four mongrel dogs were used in the study. The mandibular 3rd and 4th premolars were extracted. Three months later, four Brånemark implants (BR, n = 8) or Integral implants (IN, n = 8) were placed in the edentulous area of each dog. After another 3 months, an abutment connection was performed. Plaque control regiment was maintained for 30 days until the superstructure was placed (Day 0: baseline). Then the plaque control program was terminated to allow gross plaque accumulation. Clinical, radiographical and microbiological data were recorded at the baseline, and at 90 and 180 days after the termination of the plaque control. Values for the clinical indices such as probing depth, plaque index and bleeding on probing increased at day 90 on both the implant and tooth sites, and remained unchanged at day 180. Significantly more implant sites showed bleeding on probing than did tooth sites. Neither implants nor tooth sites showed clinically significant changes in mobility. No distinct bone resorption was observed over time by radiography. In microscopic morphological observations, cocci dominated at the baseline, and decreased by day 180, while the proportion of motile bacteria increased. In a culture study, black-pigmented anaerobic rods, which consisted predominantly of Porphyromonas gingivalis-like bacteria, were consistently found from the baseline to day 180. No Actinobacillus actinomycetemcomitans-like organisms were isolated. These results indicate that, although the long-term plaque accumulation did not cause marked periodontal destruction, the peri-implant tissue may be more susceptible to plaque accumulation than the periodontal tissue, and that teeth may serve as a reservoir for the bacterial colonization of the implant sulcus.
Alveolar Bone Loss↗
[Clinical study on azithromycin in 10% fine granules and 100mg capsules in the field of pediatrics].
Azithromycin (AZM), a new oral macrolide antibiotic, in 10% fine granules or 100 mg capsules was given to pediatric patients to treat various infections. The following results were obtained in our studies of AZM for its antibacterial activities against clinical isolates, its pharmacokinetics, its efficacy, and its safety. 1. MICs of AZM, erythromycin (EM) and clarithromycin (CAM) were determined against a total of 57 strains all at 10(6) cfu/ml. Among Gram-positive cocci, MICs of AZM ranged from 0.78 to > 100 micrograms/ml against Staphylococcus aureus (20 strains), from 0.05 to 0.1 microgram/ml against Streptococcus pyogenes (11 strains), and from 0.0125 to 3.13 micrograms/ml against Streptococcus pneumoniae (10 strains). These MICs were similar to those of the other macrolides. Among Gram-negative bacilli, MICs of AZM were 0.05 micrograms/ml against Moraxella subgenus Branhamella catarrhalis (1 strain), from 0.78 to 3.13 micrograms/ml against Haemophilus influenzae (9 strains), 0.78 micrograms/ml against Haemophilus parainfluenzae (1 strain) and 6.25 micrograms/ml against salmonella sp. (1 strain). These values were similar to or lower than those of the other macrolides. Against Mycoplasma pneumoniae, MICs of AZM were < or = 0.0008 micrograms/ml in three strains. One strain of M. pneumoniae showed tolerance to AZM at MIC 25 micrograms/ml. The other agents exhibited higher MIC than AZM against this organism. 2. Plasma samples were collected from five patients receiving fine granules and four patients receiving capsules for drug level determination. The patients received AZM at 10.0 approximately 16.3 mg/kg body weight once daily for 3 days. Drug concentrations in plasma at two hours after Day 3 dosing were in a range between 0.02 and 0.19 micrograms/ml for fine granules and were in a range between 0.11 and 0.42 micrograms/ml for capsules. 3. Urine samples were collected from four patients receiving fine granules and four patients receiving capsules. Drug levels were determined to be 3 micrograms/ml at post-treatment 48 hours for fine granules and post-treatment 72 hours for capsules. Urinary excretion rates of AZM in three patients on capsules lied in a range between 4.69 and 10.17%. 4. Effectiveness of AZM in fine granules was evaluated in 128 patients having a total of 19 different infections. AZM was rated "excellent" in 51 patients, "good" in 63, "fair" in 8, "poor" in 6, resulting in an efficacy rate of 89.1%. Effectiveness of AZM in capsular form was evaluated in 23 patients with five different infections. AZM was found "excellent" in 13 patients and "good" in 10, resulting in an efficacy rate of 100%. 5. AZM in fine granules eradicated 45 strains of 54 in 8 different bacteria. AZM in capsules eradicated 9 strains of 10 strains in 6 different bacteria. 6. As for adverse reactions, one patient complained of eruption, one vomiting, one loose stool, five diarrhea, when administered with fine granular form of AZM. One patient on AZM capsules experienced urticaria and vomiting. 7. As for abnormal laboratory changes, three patients were found with decreased WBC, seven with increased eosinophil, two with increased GOT and GPT, one with increased GPT. They were all on fine granular form of AZM. As far as abnormalities found in patients administered with AZM in capsular form, two showed decreased WBC, one decreased WBC along with increased eosinophil, and three increased eosinophil.
Adolescent↗
Mutations in the hepatocyte nuclear factor-1alpha gene in maturity-onset diabetes of the young (MODY3)
The disease non-insulin-dependent (type 2) diabetes mellitus (NIDDM) is characterized by abnormally high blood glucose resulting from a relative deficiency of insulin. It affects about 2% of the world's population and treatment of diabetes and its complications are an increasing health-care burden. Genetic factors are important in the aetiology of NIDDM, and linkage studies are starting to localize some of the genes that influence the development of this disorder. Maturity-onset diabetes of the young (MODY), a single-gene disorder responsible for 2-5% of NIDDM, is characterized by autosomal dominant inheritance and an age of onset of 25 years or younger. MODY genes have been localized to chromosomes 7, 12 and 20 (refs 5, 7, 8) and clinical studies indicate that mutations in these genes are associated with abnormal patterns of glucose-stimulated insulin secretion. The gene on chromosome 7 (MODY2) encodes the glycolytic enzyme glucokinases which plays a key role in generating the metabolic signal for insulin secretion and in integrating hepatic glucose uptake. Here we show that subjects with the MODY3-form of NIDDM have mutations in the gene encoding hepatocyte nuclear factor-1alpha (HNF-1alpha, which is encoded by the gene TCF1). HNF-1alpha is a transcription factor that helps in the tissue-specific regulation of the expression of several liver genes and also functions as a weak transactivator of the rat insulin-I gene.
Animals↗
Novel sulfated oligosaccharides containing 3-O-sulfated glucuronic acid from king crab cartilage chondroitin sulfate K. Unexpected degradation by chondroitinase ABC.
We prepared a series of oligosaccharides from king crab cartilage chondroitin sulfate K after exhaustive digestion with testicular hyaluronidase, and determined the structures of four tetrasaccharides and a pentasaccharide by fast atom bombardment mass spectrometry, high performance liquid chromatography analysis of chondroitinase AC-II digests, and 500-MHz 1H NMR spectroscopy. The tetrasaccharides shared the common core structure GlcAbeta1-3GalNAcbeta1-4GlcAbeta1-3GalNAc with various sulfation profiles. One structure was GlcAbeta1-3GalNAc(4S)beta1-4GlcAbeta1-3GalNAc(4S), whereas three of them have the following hitherto unreported structures including a novel glucuronate 3-O-sulfate: GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcAbeta1-3GalNAc(4S), GlcAbeta1-3GalNAc(4S)beta1-4GlcA(3S)beta1-3GalNAc(4S), and GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcA(3S)beta1-3GalNAc(4S), where 3S or 4S represents 3-O- or 4-O-sulfate, respectively. The structure of the pentasaccharide was determined as GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcA(3S)beta1- 3GalNAc(4S)beta1-4GlcA. Chondroitinase ABC digestion of the tetrasaccharides with GlcA(3S) at the internal position destroyed the disaccharide unit containing GlcA(3S) derived from the reducing side and resulted in only the disaccharide unit from the non-reducing side. In contrast, these tetrasaccharides remained totally resistant to chondroitinase AC-II. The results indicated that it is necessary to reevaluate the disaccharide composition of chondroitin sulfate poly- or oligosaccharides purified from various biological sources, since they were usually determined after chondroitinase ABC digestion. It is probable that the structures containing GlcA(3S) would not have been detected.
Animals↗
High prevalence of a 30-base pair deletion and single-base mutations within the carboxy terminal end of the LMP-1 oncogene of Epstein-Barr virus in the Japanese population.
The presence of 30-base pair (bp) deletion mutants within the carboxy terminal end of the LMP-1 oncogene (BNLF-1 gene) of Epstein-Barr virus (EBV) has been reported in EBV-associated neoplasms. We analysed the 30-bp deletion and the single-base mutations of the LMP-1 gene in 13 spontaneously established lymphoblastoid cell lines (LCLs) from peripheral blood mononuclear cells of three healthy children, four patients with EBV-unrelated acute febrile illnesses, three patients with infectious mononucleosis (IM), and three patients with chronic active EBV infection (CEBV), and six frozen samples from four patients with CEBV and two patients with EBV-associated hemophagocytic syndrome (EBV-AHS). For molecular analysis of the carboxy terminal end of the LMP-1 gene, PCR was performed using primers spanning the carboxy terminal region of the LMP-1 gene. Direct sequence analysis of the PCR products revealed identical 30-bp deletion in 14 of 19 samples (74%). Six point mutations at nucleotide positions 168357, 168355, 168320, 168308, 168295, and 168225 were frequently identified regardless of disease status. Our findings revealed the carboxy terminal end of the LMP-1 gene was mutational hot spots. The 30-bp deletion mutant is widely spread in the Japanese population and is not implicated in EBV-associated lymphoproliferative diseases.
Adolescent↗
Collagen-binding activity of plasma vitronectin in chronic liver disease.
The collagen-binding activity of plasma vitronectin was measured in 15 control subjects and 64 subjects with chronic liver disease. The assay of collagen-binding vitronectin was performed by an enzyme immunoassay using a monoclonal antibody to human vitronectin and type I collagen from human placenta. The plasma collagen-binding vitronectin concentration (mean +/- S.D.) was 5.6 +/- 1.9 micrograms/ml in the controls, 8.3 +/- 1.1 micrograms/ml in chronic persistent hepatitis, 8.3 +/- 2.9 micrograms/ml in chronic active hepatitis, 7.8 +/- 2.9 micrograms/ml in liver cirrhosis and 8.2 +/- 2.1 micrograms/ml in hepatocellular carcinoma with cirrhosis. The percent collagen-binding vitronectin to total plasma vitronectin was 2.2 +/- 0.8% in the controls, 3.9 +/- 2.2% in chronic persistent hepatitis, 3.9 +/- 1.2% in chronic active hepatitis, 5.8 +/- 3.3% in liver cirrhosis and 4.1 +/- 1.2% in hepatocellular carcinoma with cirrhosis. The plasma collagen-binding vitronectin also correlated with the serum levels of 7S collagen and hyaluronic acid. These findings suggest that vitronectin may play an important role in the progression of liver disease and/or in hepatic fibrosis through its collagen-binding domain.
Aged↗
Conformationally restricted analogs of 1 alpha, 25-dihydroxyvitamin D3 and its 20-epimer: compounds for study of the three-dimensional structure of vitamin D responsible for binding to the receptor.
Two proteins play important roles in the expression of vitamin D function: the specific nuclear receptor protein (vitamin D receptor, VDR) and the transport protein (vitamin D binding protein, DBP). This study was conducted to clarify the conformation of vitamin D responsible for binding to those proteins. For the purpose, the side chain mobility of 1,25(OH)2D3 (1) and its 20-epimer, 20-epi-1,25(OH)2D3 (2), was analyzed by a systematic conformational search. The results were depicted as a three-dimensional dot map, which indicates that the side chains of the two vitamins (1 and 2) occupy different spatial regions that are separated in two areas. We denoted these areas as A and G for 1 and EA and EG for 2. Four analogs, the diastereomers at C(20) and C(22) (3-6) of 22-methylated 1,25(OH)2D3 whose side chains were confined to occupy G, A, EA, and EG, respectively, were designed. These analogs (3-6) were synthesized efficiently by a stereoselective conjugate addition of organocuprate to steroidal E- and Z-22-en-24-ones as the key step. In binding to the VDR the affinities of the analogs (3-6) relative to 1,25-(OH)2D3 (1) were 1/60, 1/3, 20, and 1/100, respectively. These results indicate that the A region is responsible for binding of 1 to VDR and the EA region for binding of 2. Only isomer 4 showed significant affinity for DBP, indicating only the A region is responsible for binding to DBP. Thus, 5 showed clear separation of binding affinities for two proteins, VDR and DBP. Having the highest known VDR affinity, (22R)-22-methyl-20-epi-1,25(OH)2D3 (5) has potential both as a therapeutic agent and as a tool to study the molecular mechanism of vitamin D-mediated gene transcription.
Animals↗
Human 25-hydroxyvitamin D3-24-hydroxylase, a multicatalytic enzyme.
Human 25-hydroxyvitamin D-24-hydroxylase has been expressed in Spodoptera frugiperda (Sf21) insect cells using the previously cloned cDNA in baculovirus (AcNPV-P450cc24). The activity of recombinant h-P450cc24 required adrenodoxin, adrenodoxin reductase, and NADPH. Incubation of this reconstituted system with 25-OH-[26,27-(3)H]D3 substrate produced several metabolites that were resolved on a normal-phase cyano HPLC system. These products exactly comigrated with authentic standards for 24-oxo-25-OH-D3, 23(S),25-(OH)2D3, 24(R),25-(OH)2D3, and 24-oxo-23(S),25-(OH)2D3. The soluble proteins from Sf21 cells infected with wild-type baculovirus produced neither 24,25-(OH)2D3 nor any of the other 25-OH-D3 metabolites. The products were isolated and subjected to a normal-phase amino HPLC for further separation, purification, and characterization. Comigration on two HPLC systems, periodate cleavage reactions, and NaBH4 reduction established clearly the identity of these metabolites. Incubation of recombinant h-P450cc24 with 25-OH-[3 alpha-3H]D3 led to the isolation of an additional product that comigrated with 24,25,26,27-tetranor-23-OH-D3. Treatment of putative 24,25,26,27-tetranor-23-OH-[3 alpha-3H]D3 with acetic anhydride changed its migration on amino HPLC to a less polar position, indicating acetylation of a hydroxyl group(s). These data demonstrate conclusively that h-P450cc24 is a multicatalytic enzyme catalyzing most, if not all, of the reactions in the C-24/C-23 pathway of 25-OH-D3 metabolism. It is likely that this enzyme by itself converts 25-OH-D3 and 1,25-(OH)2D3 to one of its final excretion products.
Animals↗
Structures of five sulfated hexasaccharides prepared from porcine intestinal heparin using bacterial heparinase. Structural variants with apparent biosynthetic precursor-product relationships for the antithrombin III-binding site.
Porcine intestinal heparin was extensively digested with Flavobacterium heparinase and size-fractionated by gel chromatography. Subfractionation of the hexasaccharide fraction by anion exchange high pressure liquid chromatography yielded 10 fractions. Six contained oligosaccharides derived from the repeating disaccharide region, whereas four contained glycoserines from the glycosaminoglycan-protein linkage region. The latter structures were reported recently (Sugahara, K., Tsuda, H., Yoshida, K., Yamada, S., de Beer, T., and Vliegenthart, J.F.G. (1995) J. Biol. Chem. 270, 22914-22923). In this study, the structures of one tetra- and five hexasaccharides from the repeat region were determined by chemical and enzymatic analyses as well as 500-MHz 1H NMR spectroscopy. The tetrasaccharide has the hexasulfated structure typical of heparin. The five hexa- or heptasulfated hexasaccharides share the common core pentasulfated structure delta HexA(2S) alpha 1-4GlcN-(NS, 6S) alpha 1-4IdoA alpha/GlcA beta 1-4GlcN(6S) alpha 1-4GlcA beta 1-4GlcN (NS) with one or two additional sulfate groups (delta HexA, GlcN, IdoA, and GlcA represent 4-deoxy-alpha-L-threo-hex-4-enepyranosyluronic acid, D-glucosamine, L-iduronic acid, and D-glucuronic acid, whereas 2S, 6S and NS stand for 2-O-, 6-O-, and 2-N-sulfate, respectively). Three components have the following hitherto unreported structures: delta HexA(2S) alpha 1-4GlcN(NS, 6S) alpha 1-4GlcA beta 1-4GlcN(NS, 6S) alpha 1-4GlcA beta 1-4GlcN(NS,6S), delta HexA(2S) alpha 1-4GlcN(NS, 6S) alpha 1-4IdoA alpha 1-4GlcNAc(6S)-alpha 1-4GlcA beta 1-4GlcN(NS, 3S), and delta HexA(2S) alpha 1-4GlcN-(NS,6S) alpha 1-4IdoA (2S) alpha 1-4GlcNAc(6S) alpha 1-4GlcA beta 1-4GlcN(NS, 6S). Two of the five hexasaccharides are structural variants derived from the antithrombin III-binding sites containing 3-O-sulfated GlcN at the reducing termini with or without a 6-O-sulfate group on the reducing N,3-disulfated GlcN residue. Another contains the structure identical to that of the above heptasulfated antithrombin III-binding site fragment but lacks the 3-O-sulfate group and therefore is a pro-form for the binding site. Another has an extra sulfate group on the internal IdoA residue of this pro-form and therefore can be considered to have diverged from the binding site in the biosynthetic pathway. Thus, the isolated hexasacharides in this study include the three overlapping pairs of structural variants with an apparent biosynthetic precursor-product relationship, which may reflect biosynthetic regulatory mechanisms of the binding site.
Animals↗