Mental dysfunction in water intoxication brain edema.
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
M Yamaguchi
Publications and source records attributed to M Yamaguchi.
Effect of dipicolinate, a chelator of zinc, on bone protein synthesis in tissue culture. The essential role of zinc.
The present investigation was undertaken to clarify the essential role of zinc on bone protein synthesis in tissue culture. Calvariae were removed from 3-week-old male rats and cultured for periods up to 72 hr in Dulbecco's Modified Eagle Medium (high glucose, 4500 mg/dl) supplemented with antibiotics and bovine serum albumin. The calvariae were incubated for 24 hr at 37 degrees in 5% CO2/95% air in medium containing 10(-6)-10(-3) M dipicolinate, a chelator of zinc, and then the bones were transferred into medium containing either 10(-4) M zinc sulfate or vehicle without dipicolinate. Zinc content in bone tissues was decreased when the culture was treated with 10(-4) and 10(-3) M dipicolinate for 24 hr. When calvariae treated with 10(-4) M dipicolinate for 24 hr were further cultured in medium without dipicolinate for 24 and 48 hr, bone alkaline phosphatase activity was decreased by about 40% (P less than 0.01) of untreated bone enzyme activity. The decreased alkaline phosphatase activity was increased markedly by the presence of 10(-4) M zinc (about 2.5-fold of control value). This effect of zinc was blocked completely by the presence of 10(-7) M cycloheximide, but 10(-8) M actinomycin D caused only a partial inhibition. When calvariae treated with 10(-4) M dipicolinate were pulsed with [3H]proline, the incorporation of [3H]proline into the acid-insoluble residues of bone tissue was decreased by about 40% (P less than 0.01) of the value obtained from calvariae not treated with dipicolinate. The presence of 10(-4) M zinc caused an increase of about 2-fold in [3H]proline incorporation. Bone DNA content was not altered significantly by treatment with 10(-4) dipicolinate or 10(-4) M zinc. These results clearly indicate that endogenous zinc induces the stimulation of protein synthesis at the translational process in bone cells. The present study further supports the view that zinc plays an essential role for protein synthesis in bone cells.
Alkaline Phosphatase↗
Effect of 1,25-dihydroxyvitamin D3 on bone metabolism in tissue culture. Enhancement of the steroid effect by zinc.
The present investigation was undertaken to clarify the interaction of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and zinc on bone metabolism in tissue culture. Calvaria were removed from weanling rats (3-week-old males) and cultured for periods up to 96 hr in Dulbecco's Modified Eagle Medium (high glucose, 4500 mg/dl) supplemented with antibiotics and bovine serum albumin. The experimental cultures contained 10(-10) to 10(-6) M 1,25(OH)2D3. All cultures were incubated at 37 degree in 5% CO2/95% air. Bone calcium content was increased significantly by the presence of 10(-9) to 10(-7) M 1,25(OH)2D3. The steroid (10(-9) to 10(-7) M) also significantly increased alkaline phosphatase activity in the bone, whereas it did not alter significantly acid phosphatase activity. [3H]Leucine incorporation by the bone was raised significantly by 10(-8) to 10(-7) M 1,25(OH)2D3. Furthermore, bone DNA content was increased significantly by 10(-9) to 10(-7) M 1,25(OH)2D3. Meanwhile, the presence of 10(-4) M zinc, which can stimulate bone formation, significantly enhanced the effect of 10(-7) M 1,25(OH)2D3 to increase alkaline phosphatase activity and DNA content in rat calvaria. The present study demonstrates that 1,25(OH)2D3 has a direct stimulatory effect on bone metabolism in tissue culture and that zinc can enhance the steroid effect.
Alkaline Phosphatase↗
Repression of polyoma virus DNA replication by 5'-flanking region of mouse DNA polymerase beta gene containing transcriptional silencer elements.
Dual cis-acting silencer elements are located upstream of the mouse DNA polymerase beta gene (Yamaguchi, M., Hayashi, Y., and Matsukage, A. (1989) J. Biochem. (Tokyo) 105, 79-83). In order to examine possible involvement of transcriptional silencer elements in the regulation of DNA replication, we have utilized a transient replication system of the plasmid DNA carrying replication origin of polyoma virus DNA in mouse MOP8 cells, which is constitutively producing polyoma virus large T-antigen. The polyoma virus origin of DNA replication is composed of three cis-acting genetic elements called alpha, beta, and core, in which alpha and beta elements correspond to enhancer domains. When the 5'-flanking regions of the DNA polymerase beta gene containing silencer elements were placed at the late gene border of alpha element, they effectively repressed the DNA replication. However, when placed at the early gene border of core element, it only marginally repressed the DNA replication. These results suggest that the silencer elements at cis position repress polyoma virus DNA replication by impeding the enhancer function that activates the DNA replication.
Animals↗
Cancer superimposed on adult T-cell leukemia.
Forty-three patients with adult T-cell leukemia (ATL), admitted to the hospital from 1982 to 1987, were studied. Five of those were found to have additional cancer; two of the five had two additional kinds of cancers besides ATL. During the same period, in contrast, the authors encountered only three patients with some superimposed cancer among 155 cases of hematologic malignancies which had no association with human T-cell lymphotropic virus type I (HTLV-I). These facts strongly suggest that HTLV-I infection is not only associated with ATL, but it is likely to increase the incidence of other types of malignancy as well.
Aged↗
Ultramicro determination of 7-dehydrocholesterol in rat skin by high-performance liquid chromatography with fluorescence detection.
Explore the source record for details and available documents.
Animals↗
Mitochondrial nicotinamide nucleotide transhydrogenase: NADPH binding increases and NADP binding decreases the acidity and susceptibility to modification of cysteine-893.
The mitochondrial nicotinamide nucleotide transhydrogenase is a dimeric enzyme of monomer Mr 110,000. It is located in the inner mitochondrial membrane and catalyzes hydride ion transfer between NAD(H) and NADP(H) in a reaction that is coupled to proton translocation across the inner membrane. The amino acid sequence and the nucleotide binding sites of the enzyme have been determined [Yamaguchi, M., Hatefi, Y., Trach, K., & Hoch, J.A. (1988) J. Biol. Chem. 263, 2761-2767; Wakabayashi, S., & Hatefi, Y. (1987) Biochem. Int. 15, 915-924]. N-Ethylmaleimide, as well as other sulfhydryl group modifiers, inhibits the transhydrogenase. The presence of NADP in the incubation mixture suppressed the inhibition rate by N-ethylmaleimide, and the presence of NADPH greatly increased it. NAD and NADH had little or no effect. The NADPH effect was concentration dependent and saturable, with a half-maximal NADPH concentration effect close to the Km of the enzyme for NADPH. Study of the effect of pH on the N-ethylmaleimide inhibition rate showed that NADPH binding by the enzyme lowers the apparent pKa of the N-ethylmaleimide-sensitive group by 0.4 of a pH unit and NADP binding raises this pKa by 0.4 of a pH unit, thus providing a rationale for the effects of NADP and NADPH on the N-ethylmaleimide inhibition rate. With the use of N-[3H]ethylmaleimide, the modified sulfhydryl group involved in the NADP(H)-modulated inhibition of the transhydrogenase was identified as that belonging to Cys-893, which is located 113 residues upstream of the tyrosyl residue modified by [p-(fluorosulfonyl)benzoyl]-5'-adenosine at the putative NADP(H) binding site of the enzyme (see above references).(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗
Paradoxical effect of Simian virus 40 enhancer on the function of mouse DNA polymerase beta gene promoter.
Simian virus (SV) 40 enhancer (nucleotide position 108 to 294) was combined with chloramphenicol acetyltransferase (CAT) plasmid whose expression is under control of mouse DNA polymerase beta gene promoter. Although the SV40 enhancer stimulated the transient CAT-expression directed by the DNA polymerase beta gene promoter two to three fold in human HeLa cells, it repressed the CAT-expression by 50 to 60% in mouse NIH/3T3 cells. The repression was observed relatively independently on the orientation of the insertion and the distance from the promoter. These properties of the enhancer are very similar to those of so-called transcriptional silencer element. In both HeLa and NIH/3T3 cells, the SV40 enhancer stimulated effectively its own early gene promoter-directed CAT-expression. In mouse immature T-cell line RV-1 in which the SV40 promoter-enhancer did not function, no effect of the SV40 enhancer sequence on the DNA polymerase beta promoter-directed CAT-expression was observed. Thus, it is suggested that both cell type-specific trans-acting factor(s) and the specific combination with the promoter sequence turn the properties of the SV40 enhancer into those of a silencer.
Animals↗
Determination of mono-O-acetylated N-acetylneuraminic acids in human and rat sera by fluorometric high-performance liquid chromatography.
A simple, rapid, and highly sensitive fluorometric high-performance liquid chromatographic method for the determination of N-acetylneuraminic acid and its mono-O-acetyl derivatives in human and rat sera is described. The neuraminic acids, released by hydrolysis of serum in 2 M acetic acid, are converted with 1,2-diamino-4,5-methylenedioxybenzene, a fluorogenic reagent for alpha-keto acids, to highly fluorescent derivatives without the occurrence of O-acetyl migration and de-O-acetylation. The derivatives are separated isocratically within 25 min by reversed-phase chromatography using a TSK gel ODS-120T column. The limits of detection are 57-192 fmol in a 10-microliters injection volume at a signal-to-noise ratio of 3. This sensitivity permits precise determination of the neuraminic acids in 5 microliters of human and rat sera.
Animals↗
Measurement of 21-hydroxycorticosteroids in human and rat sera by high-performance liquid chromatography with fluorimetric detection.
Explore the source record for details and available documents.
Adult↗
Differences in prognostic factors between leukemia and lymphoma type of adult T-cell leukemia.
Prognostic factors affecting the survival of adult T-cell leukemia (ATL) patients were analyzed in three groups: total cases, leukemia type cases, and lymphoma type cases. Factors found to be important overall, i.e. for total cases, were leukocyte count, ATL cell ratio in the peripheral blood, serum calcium levels and lactate dehydrogenase (LDH) level. Of those, LDH level proved not significant when evaluated separately for leukemia type or lymphoma type cases. Leukocyte count and ATL cell ratio were significant in leukemia type patients, whereas it was serum calcium level that was significant in lymphoma type; there were mutually exclusive sets of factors for the two groups. Thus, prognostic factors for ATL patients should be considered separately for each type of the disease.
Adult↗
Diffuse panbronchiolitis as a pulmonary complication in patients with adult T-cell leukemia.
Forty-three cases of adult T-cell leukemia (ATL) admitted to our hospital between 1982 and 1987 were studied. Three of those were found to be complicated with diffuse panbronchiolitis (DPB). The incidence of DPB is considered to be significantly higher in patients with ATL. The three DPB-complicated cases composed one case each of the smoldering, chronic, and acute type of ATL. In each type, DPB preceded overt ATL and Candida albicans was found in sputa following detection for bacteria. The DPB complication apparently worsened the prognosis of the ATL patients. We have discussed a possible relationship between ATL and DPB.
Adult↗
Cell-type-specific expression of mouse DNA polymerase beta-gene is regulated by silencer elements.
RNA blot hybridization analysis revealed that the steady-state level of DNA polymerase beta-mRNA in mouse neuroblastoma N18TG2 cells was approximately five-fold higher than that in NIH/3T3 cells. In order to examine the function of DNA polymerase beta-gene silencers in these two cell lines, we employed a chloramphenicol acetyltransferase (CAT)-transient expression assay using the CAT plasmids containing the silencers linked to various promoter-enhancers. In NIH/3T3 cells, DNA polymerase beta-gene silencers effectively repressed the function of its own promoter and those of several other heterologous promoter-enhancers. In contrast, the silencers only marginally affected the CAT expression directed by DNA polymerase beta-gene promoter and heterologous promoter-enhancers in N18TG2 cells. The extent of the increase of CAT expression by removing silencer elements in NIH/3T3 cells was very similar to the ratio of DNA polymerase beta-mRNA content in N18TG2 cells to that in NIH/3T3 cells. These results indicate that cell-type-specific expression of DNA polymerase beta-gene is primarily controlled by the function of its silencer elements.
Animals↗
An alpha-specific gene, SAG1 is required for sexual agglutination in Saccharomyces cerevisiae.
Seven alpha-specific mutants specifically defective in sexual agglutinability were isolated. The other alpha mating functions exhibited by these mutants, designated sag mutants, such as the production of alpha pheromone and response to a mating pheromone, were normal. While the MAT alpha sag1 cells did not agglutinate with wild-type a cells, the MATa sag1 cells did, indicating that the SAG1 gene is expressed only in alpha cells. The mutations were semi-dominant and fell into a single complementation group, SAG1, which was mapped near met3 on chromosome X. Complementation analysis showed that sag1 and ag alpha 1, the latter being a previously reported alpha-specific mutation, were mutations in the same gene.
Genes, Fungal↗
Simulated weightlessness and bone metabolism: decreases of protein and DNA syntheses in the femoral diaphysis of rats.
The effect of simulated weightlessness on bone protein and DNA syntheses was investigated in the skeletal unloading for up to 4 days. The skeletal unloading was designed by using the model of hindlimb hang in rats. The femoral-diaphyseal fragments obtained from rats which bred with skeletal unloading were cultured for 3 h at 37 degrees C in 5% CO2/95% air in Dulbecco's Modified Eagle Medium (high glucose). When the bone tissues were pulsed with [3H]proline, the incorporation of [3H]proline into the bone protein was significantly decreased by skeletal unloading. In the pulse with [14C]uridine, the incorporation of [14C]uridine into the bone RNA was significantly reduced by skeletal unloading. Moreover, the incorporation of [3H]thymidine into the acid-insoluble residues of bone tissue was significantly decreased by skeletal unloading. Also, DNA content in the femoral diaphysis was significantly reduced by skeletal unloading. These findings suggest that skeletal unloading causes the decreases of protein and DNA syntheses in the femoral diaphysis of rats.
Animals↗
Simulated weightlessness and bone metabolism: decrease of alkaline phosphatase activity in the femoral diaphysis of rats.
The effect of simulated weightlessness on bone metabolism was investigated in the skeletal unloading for up to 9 days. The skeletal unloading was designed by using the model of hindlimb hang in rats. The food ingestion of rats with the skeletal unloading was not altered in comparison to that of normal rats. Calcium concentration in the serum was not significantly altered by the skeletal unloading for 9 days, while the serum inorganic phosphorus concentration was significantly decreased at 6 and 9 days. Calcium content in the femoral diaphysis was not altered by the skeletal unloading for 9 days. However, the activities of alkaline and acid phosphatases in the femoral diaphysis were markedly decreased by the skeletal unloading. The decrease in bone alkaline phosphatase activity was seen at 2 days with the skeletal unloading. The present results demonstrate that the skeletal unloading with hindlimb hang can induce the disorder of bone metabolism. This model is useful for studying the effects of simulated weightlessness on bone metabolism.
Alkaline Phosphatase↗
Effect of vanadium on bone metabolism in weanling rats: zinc prevents the toxic effect of vanadium.
The effect of vanadium on bone metabolism was investigated in the femoral diaphysis of weanling rats. Vanadium pentoxide (1.0-20.0 mumol V/100 g b.wt.) was administered orally for 3 days. The doses of 15.0 and 20.0 mumol V/100 g caused a significant increase in serum calcium concentration. Bone alkaline phosphatase activity was increased significantly by the doses of 1.0-20.0 mumol V/100 g, while bone acid phosphatase activity was not altered significantly. Bone DNA content was increased significantly by the dose of 1.0-10.0 mumol V/100 g. Bone calcium content was not altered significantly by administration of vanadium. The increase in serum calcium concentration caused by administration of vanadium (20.0 mumol/100 g) was prevented completely by simultaneous injection of zinc sulfate (15.3 mumol Zn/100 g) for 3 days, although zinc alone did not have any effect. Administration of zinc (15.3 mumol/100 g) produced an appreciable increase in bone alkaline phosphatase activity, DNA content, and calcium content. These increases were not enhanced significantly by simultaneous injection of vanadium (2.0 and 20.0 mumol V/100 g). The present study indicates that a comparatively low dose of vanadium may play a nutritional role in bone formation of weanling rats, and that zinc can prevent the relevation of the toxic effect of vanadium with higher doses.
Acid Phosphatase↗
Diastolic compliance of the left atrium in man: a determinant of preload of the left ventricle.
During the ventricular slow-filling period, both the left atrium and left ventricle fill passively, and their respective internal pressures equalize, becoming evenly elevated. If the diastolic chamber compliance of the left atrium is smaller than that of the left ventricle, we expect the inflowing blood to be distributed more to the left ventricle than to the left atrium during this period. We examined the magnitude of the diastolic compliance of the left atrium and the left ventricle at the end of the slow-filling period. We studied 10 patients, mostly with a mild degree of coronary artery disease, in whom hemodynamic variables were almost within normal limits. To estimate the compliance of the left atrium, we recorded the left atrial pressure directly (by the Brockenbrough technique) and determined the left atrial volume by biplane cineatriography. We determined the diastolic compliance of the left atrium from the pressure-volume relations between the nadir of the x trough and the peak of the v wave by fitting them to an exponential equation. P = b.eaV (P = pressure, V = volume, a, b = constants). The diastolic compliance of the left ventricle was determined from the pressure-volume relations during the ventricular slow-filling period. The compliances of the left atrium and the left ventricle at the pressure at the end of the ventricular slow-filling period were 1.60 +/- 0.41 (mean +/- SD) ml.mmHg-1.m-2 and 4.22 +/- 1.12, respectively. The ratio of compliance of the left ventricle to that of the left atrium was 2.60 +/- 0.71.(ABSTRACT TRUNCATED AT 250 WORDS)
Blood Pressure↗