Erratum: Recovery of YBa2Cu3O7-y etched by helium ions
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Journal Article↗
Biomedical subjects
Y Nishi
Publications and source records attributed to Y Nishi.
Structural organization of MYCN amplicons of neuroblastoma tumors, xenografts, and cell lines characterized by the sequences encompassing the MYCN amplicons in a human neuroblastoma cell line.
We characterized differences in the structural organization of the MYCN amplicons of a number of neuroblastomas by analyzing 8 contigs spanning 330 kb cloned from the MYCN amplicon of a neuroblastoma cell line. Some regions were amplified in almost all specimens, the conserved regions (CRs), and others were differentially amplified in some subsets, the non-conserved regions (NCRs). CRs constituted only 20% of the 330 kb region, with the remainder being NCRs. The regions that inevitably co-segregate with the MYCN gene make up the core, whereas flanking regions are retained at random. If a histogram of the frequency with which the amplified NCR sequences from one specimen match those of the cell line MC-NB-I shows a random distribution, the NCRs would co-segregate with MYCN as a result of random events. However, both the tumors and cell lines/xenografts showed a distribution with two distinct peaks; one from a group containing a small number of sequences with a fairly high degree of homology to the NCRs of MC-NB-I, and the other from a group containing a large number of sequences with little homology. These results indicate that the flanking segments are preferentially co-segregated with MYCN by a non-random mechanism.
Alleles↗
Aromatase activity in human osteoblast-like osteosarcoma cell.
Aromatase activity was studied in cultured human osteosarcoma cell (HOS). HOS was incubated from 12 to 72 hours with 10(-10) M-10(-5) M dexamethasone. Aromatase activity was determined by measuring [3H]H2O released upon the conversion of [1 beta-3H]androstenedione to estrone. HOS showed aromatase activity, and apparent km for [1 beta-3H]androstenedione was 4.46 +/- 0.98 nm (mean +/- SD). The aromatase activity was significantly increased by 10(-9) M-10(-5) M dexamethasone in a dose-dependent manner. Dexamethasone increased Vmax of aromatase activity but did not change its km value. These results suggest that osteoblastic cells have aromatase activity which is regulated by glucocorticoid, and directly convert androgen to estrogen in itself.
Androstenedione↗
Genetic variations in baseline and ultraviolet light-induced sister chromatid exchanges in peritoneal lymphocytes among different mouse strains.
The variation in the induction of sister chromatid exchanges (SCEs) in the peritoneal lymphocytes of different mouse strains was investigated. For the baseline SCEs, BALB/c and outbred ICR showed the lowest frequency and DBA/2 and C57BL/6 the highest. BDF1 (C57BL/6 x DBA/2) was ranked among the highest, while CDF1 (BALB/c x DBA/2) was intermediate between the parental strains. Regarding UV-induced SCEs, BALB/c was less susceptible as compared to DBA/2 and C57BL/6. Both BDF1 and CDF1 showed values significantly higher than BALB/c, but not significantly different from DBA/2 or C57BL/6. ICR was ranked in the susceptible group. For the baseline SCEs of bone marrow cells, the overall ranking among strains was essentially the same as that for the baseline, but different from that for the UV-induced, SCEs in peritoneal lymphocytes. The present results can be explained by assuming that the major genetic factor contributing to the strain-dependent difference in the baseline SCEs is due to a codominant trait of a single allele, but that the UV-induced SCEs are complicated by other genetic factor(s).
Animals↗
Obstruction of the St. Jude Medical valve--diagnostic and therapeutic values of cineradiography.
Between 1984, and 1992, we observed 8 patients with an obstructed St. Jude Medical (SJM) valve. Of these, 1 had an obstructed SJM valve in the aortic position, 3 in the mitral position, and 4 in the tricuspid position. Diagnosis of obstruction of the SJM valve was made by cineradiography combined with echocardiography in all 8 patients. Restriction or absence of movement of the leaflet of the SJM valve was observed by cineradiography in all of the 8 patients. Normal range of leaflet mobility of the SJM valve was measured by conventional cineradiography in 70 patients with a normal SJM valve, and the results were compared with the leaflet mobility obtained from the 8 patients with an obstructed SJM valve. In this study, leaflet function in the obstructed SJM valve was strikingly abnormal, with both opening and closing angles, and leaflet motion clearly outside the normal range. Of the 8 patients, 4 underwent urgent prosthetic valve replacements after cineradiography and echocardiography were carried out. Thrombolysis using urokinase was performed in 4 patients, and this treatment was successful in 1 patient. Efficacy of thrombolytic therapy was evaluated by repeat cineradiography. Three of the 4 patients who received thrombolysis showed no significant improvement of leaflet mobility after at least 72 hours of thrombolytic therapy, and finally required surgical correction for the obstructed SJM valve. We believe that cineradiography combined with echocardiography is the optimal method for the diagnosis of obstruction of the SJM valve, and to follow the effect of thrombolytic therapy on prosthetic valve function.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
A new mutation causing inherited growth hormone deficiency: a compound heterozygote of a 6.7 kb deletion and a two base deletion in the third exon of the GH-1 gene.
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Adolescent↗
A case of squamous cell lung carcinoma with high concentration of parathyroid hormone-related peptide in serum and pleural effusion presenting hypercalcemia.
A 57-year-old man with lung squamous cell carcinoma revealed hypercalcemia, hypophosphoremia, elevation of nephrogenous cAMP and metabolic alkalosis. Serum parathyroid hormone (PTH) and 1,25(OH)2D3 concentrations were not elevated. These findings were consistent with those in humoral hypercalcemia of malignancy (HHM). PTH-related peptide (PTHrP) concentrations were determined using N- and C-terminal specific radioimmunoassays (PTHrP-N, PTHrP-C), and elevation of both PTHrP-N and PTHrP-C concentrations in the serum was noted (PTHrP-N, 27 pmol/liter (normal < 5); PTHrP-C, 1408 pmol/liter (normal < 50)). High concentration of PTHrP (946 pmol/liter for PTHrP-N and 5983 pmol/liter for PTHrP-C) was also found in the pleural fluid obtained at autopsy. Immunohistochemical study, using paraffin-embedded sections of the tumor tissue obtained at autopsy, revealed numerous PTHrP-positive cells and expression of PTHrP gene was confirmed by Northern blot analysis. These findings indicate that PTHrP, produced in the tumor tissue, was secreted into the blood stream, which caused HHM in the patient. Gel permeation chromatography of the serum and pleural fluid revealed several peaks of both PTHrP-N and PTHrP-C. Molecular forms of PTHrP-N were larger than those of PTHrP-C in the serum as well as pleural fluid. These findings indicate that multiple forms of PTHrP molecules are present in the serum and pleural fluid. Granulocytosis was also noted in the patient. However, granulocyte- and granulocyte macrophage-colony stimulating factor were not detected in the serum, and the mechanism of the granulocytosis in the patient was unclear.
Blotting, Northern↗
Treatment of isolated growth hormone deficiency type IA due to GH-I gene deletion with recombinant human insulin-like growth factor I.
Biosynthetic insulin-like growth factor I (IGF-I) was administered subcutaneously twice a day for one year to a patient with isolated growth hormone deficiency (IGHD) type IA with high titres of anti-GH antibody (up to 1:1,000,000). During IGF-I therapy he showed good linear growth without any side effects, such as hypoglycemia and anti-IGF-I antibody formation. Administration of IGF-I to IGHD type IA with poor response to GH therapy appears to have a beneficial effect on growth.
Antibodies↗
Persistent synchronous periodic discharges caused by anoxic encephalopathy due to cardiopulmonary arrest.
We report a patient with vegetative state induced by anoxic encephalopathy due to cardiopulmonary arrest who showed synchronous periodic discharges for a prolonged period. The patient was a 47-year-old man admitted to our hospital for depression, who suddenly developed cardiopulmonary arrest of unknown etiology, and entered chronic vegetative state as a result of anoxic encephalopathy. Electroencephalography (EEG) revealed that synchronous periodic discharges were present for up to 5 months. The wave pattern, periodicity and duration of appearance of synchronous periodic discharges were similar to those of synchronous periodic discharges in Creutzfeldt-Jakob disease (CJD). The periodicity of synchronous periodic discharges was gradually prolonged, with the course again similar to the discharges in CJD. The mechanism of occurrence is considered to be similar to that of synchronous periodic discharges in CJD.
Arousal↗
High expression of cytochrome b5 in adrenocortical adenomas from patients with Cushing's syndrome associated with high secretion of adrenal androgens.
The mechanism of dissociated secretion between adrenal androgens and cortisol observed in several clinical situations remains unclear. We investigated whether the electron transfer systems NADPH-cytochrome P450 reductase and cytochrome b5, both of which had been shown to increase 17,20-lyase activity in vitro, were involved in the reaction selectivity between 17 alpha-hydroxylase and 17,20-lyase in adrenocortical adenomas obtained from eight patients with Cushing's syndrome producing different concentrations of adrenal androgen. In vitro enzyme assay using microsomal fraction of adenoma indicated that all adenomas from seven patients showed almost the same degree of 17 alpha-hydroxylase and 3 beta-hydroxysteroid dehydrogenase (3 beta HSD) activities. However, the 17,20-lyase activities of two adenomas producing high concentrations of adrenal androgens were 3-fold greater than those of other five adenomas producing low concentrations of adrenal androgens. The mRNA concentrations of cytochrome P45017 alpha and 3 beta HSD were approximately the same in all adenomas, whereas those of cytochrome b5 in two adenomas possessing high 17,20-lyase activities were greater than those in other adenomas. The increased levels of cytochrome b5 in the two adenomas were further confirmed at the protein level using Western blot analysis of the microsomal fraction. No significant expression of NADPH-cytochrome P450 reductase was detected in any of the adenomas by Northern blot analysis. These results suggest that the difference in the concentration of cytochrome b5 in adrenal adenomas from patients with Cushing's syndrome may partially account for the difference in the amount of adrenal androgens produced by the tumors.
3-Hydroxysteroid Dehydrogenases↗
Growth hormone therapy in achondroplasia.
The status of growth hormone (GH) secretion together with the effect of GH therapy was studied in six children with achondroplasia. One patient had impaired GH secretion, which may, in part, be due to obesity. The pre-GH-treatment height velocity was 3.8 +/- 0.7 cm/year, but this increased to 6.0 +/- 1.0 cm/year in the first year of treatment and to 4.4 +/- 0.6 cm/year in the second year. One patient who underwent GH therapy for 4 years showed good response in height velocity. A considerable variation was observed in response to GH therapy within the treated cases.
Achondroplasia↗
[Isolated GH deficiency with X-linked hypogammaglobulinemia].
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Adolescent↗
Doppler echocardiographic evaluation of St. Jude Medical valves in the tricuspid position.
Sixteen of 20 patients who underwent tricuspid valve replacement with a St. Jude Medical valve at our hospital were followed for three to 164 months. Doppler echocardiographic and cineradiographic examinations of the replacement device were performed in 13 patients. There were six males and seven females in the study, with a mean age of 41.9 years. A St. Jude Medical prosthesis had also been implanted in the mitral or mitral and aortic positions of eight of these thirteen patients. Ten patients had normally functioning valves in the tricuspid position and three were diagnosed as malfunctioning. The peak velocity in those patients with normally functioning tricuspid valves was 1.3 +/- 0.2 m/sec. The calculated peak and mean pressure gradients were 6.7 +/- 1.9 mmHg and 2.6 +/- 1.1 mmHg, respectively, and the mean pressure half-time was 120 +/- 22 msec. All normally functioning valves in the tricuspid position had peak velocities of less than 1.55 m/sec, and peak and mean pressure gradients of less than 9.6 mmHg and 5 mmHg, respectively, with the pressure half-time being less than 140 msec in all cases, except for one of the three Doppler studies performed in one patient. However, three Doppler studies performed in two patients with a malfunctioning tricuspid valve revealed peak velocities, peak and mean pressure gradients and pressure half-times which were above these values. After replacement of the malfunctioning valve, or thrombolysis, all of the Doppler-derived values returned to the range found in normally functioning valves.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Recovery of YBa2Cu3O7-y etched by helium ions.
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Journal Article↗
The majority of the marker chromosomes in Japanese patients with stigmata of Turner syndrome are derived from Y chromosomes.
DNA analyses of 41 individuals with stigmata of Turner syndrome and a 45,X/46,X+mar or 46,X+mar karyotype were carried out. Southern-blot analysis employing 17 Y-specific probes were used to determine whether the marker chromosome was Y-chromosomal in origin. Of the 41 DNA samples from these patients, 23 contained detectable Y-chromosomal DNA. Points of chromosome breakage were distributed over the entire length of the Y long arm. Three individuals, who carry different portions of the Y chromosome, had developed gonadoblastoma. GBY (the gonadoblastoma locus on the Y chromosome) is mapped proximal to DYS132, midway between the 13 Yq loci that we have studied. We also used a polymerase chain reaction technique that could detect 7 loci over the length of the Y chromosome. This technique may be useful for the rapid assessment of marker chromosomes, especially for evaluating the risk of gonadoblastoma.
Blotting, Southern↗
Characterization of N-myc amplification in a human neuroblastoma cell line by clones isolated following the phenol emulsion reassociation technique and by hexagonal field gel electrophoresis.
The N-myc amplification of human neuroblastomas was characterized by the amplified DNA cloned from the cell line MC-NB-1 using the phenol emulsion reassociation technique (PERT). A number of PERT clones exhibiting amplification in this cell line were tested for amplification in other neuroblastoma cell lines. In almost all cell lines examined, only a few clones were co-amplified with N-myc and most of the others were exclusively amplified in a subset of the cell lines. The total aggregate size of the Hind III fragment identified by the PERT clones was approximately 350 kb. Most of the PERT clones were mapped to human chromosome (chr) 2p23-2pter, where the N-myc gene is located. Four types of amplicons, the 100, 420, 480 and 520 kb fragments, shown to be Not I fragments, were identified by hexagonal field gel electrophoresis. Three fragments are ordered in a head-to-tail array, and the remaining fragment is either ordered in a tail-to-head array or something else. Despite the extremely unusual construction of the amplified sequences in this cell line as compared with others, there was a low degree of sequence heterogeneity among the amplicons within this cell line. These observations lead to the idea that the complex rearrangements that give rise to the heterogeneous organization of the amplified sequences among the different cell lines precede the amplification of these sequences.
Chromosomes, Human, Pair 2↗
Mild adrenal 3 beta-hydroxysteroid dehydrogenase deficiency in children with accelerated growth, premature pubarche and/or hirsutism.
We studied eight children (seven girls and one boy, of whom three are siblings) with accelerated growth, premature pubarche and/or hirsutism between the ages of 7 and 9.5 years. These patients were studied for the presence of adrenal steroidogenic defect by adrenocortico tropic hormone (ACTH) stimulation testing (Cortrosyn, 0.25 mg iv bolus dose). Baseline and stimulated 17-hydroxypregnenolone (delta 5-17P), 17-hydroxyprogesterone (17-OHP), dehydroepiandrosterone (DHEA), androstenedione (delta 4-A), testosterone, and cortisol levels were measured. Six children, including three siblings, were diagnosed with a mild form of 3 beta-hydroxysteroid dehydrogenase deficiency based upon the elevated response of serum delta 5-17P and the elevated ratio of delta 5-17P/17-OHP and of DHEA/delta 4-A to ACTH stimulation. Thus, a mild form of 3 beta-hydroxysteroid dehydrogenase deficiency may not be uncommon in children with accelerated growth, premature pubarche and/or hirsutism and routine assay of delta 5-steroid metabolites should be generally available.
17-alpha-Hydroxypregnenolone↗
Effect of long-term calcitonin therapy by injection and nasal spray on the incidence of fractures in osteogenesis imperfecta.
The effect of calcitonin therapy by injection or nasal spray on the incidence of bone fractures was studied in patients with osteogenesis imperfecta. In contrast to injection of calcitonin, intranasal administration of calcitonin twice a week for 2 weeks, followed by 2 weeks of no therapy, was simple and seemed beneficial for decreasing bone fractures in patients with osteogenesis imperfecta.
Administration, Intranasal↗