Sensitive and selective high-performance liquid chromatographic determination of catecholamines by pre-column solid-phase dansylation is described. After catecholamines are adsorbed on alumina, the amino groups not responsible for adsorption are dansylated by a solid-phase reaction. The excess reagent and fluorescent contaminants are washed out, and the dansylated catecholamines are eluted and separated by reversed-phase high-performance liquid chromatography. The four catecholamine derivatives can be separated within 10 min and no major interfering peak is observed on chromatograms. The response of each catecholamine is linear from 10 to 500 pmol per sample and the detection limit is 0.5 pmol. This method was applied to determination of catecholamines in human urine.

Adult↗

PubMed1986

Sequential X-chromosome reactivation and inactivation in cell hybrids between murine embryonal carcinoma cells and female rat thymocytes.

By means of a 5-bromodeoxyuridine (BrdU) incorporation and an acridine orange fluorescence staining method together with [3H]thymidine ([3H]TdR) autoradiography, we studied the chronology of X-chromosome replication in newly formed cell hybrids between the hypoxanthine phosphoribosyl transferase (HPRT)-deficient OTF9-63 murine embryonal carcinoma (EC) cell with 43 +/- chromosomes and the female rat thymocyte having 42 chromosomes. Most near-tetraploid hybrid cells retained all chromosomes from both parents including one mouse X (XM) and two rat X (XR) chromosomes throughout the period of this study. Data showing changes in the chronology of X-chromosome replication obtained here were indicative of reactivation of the inactive X chromosome from the rat thymocyte, and de novo X-inactivation of one or two chromosomes. The extinction of lymphocyte phenotypes from the hybrids and their subsequent differentiation to the cell type resembling endoderm found in the peri-implantation mouse embryo apparently occurred in parallel with the above changes. These hybrids also showed an interesting possibility of preferential reinactivation of the reactivated XR chromosome in the early stages after cell fusion.

Animals↗

PubMed1986

Effects of stimulus repetition rate on slow and fast components of auditory brain-stem responses.

Effects of stimulus repetition rate on the slow and fast components of the auditory brain-stem response (ABR) were investigated in 10 adult subjects with normal hearing. The ABRs were recorded with click stimuli at repetition rates of 8, 13.3, 23.8, 40 and 90.9/sec and at an intensity level of 55 dB nHL. Power spectral analysis of the averaged responses was performed. Then the responses were divided into a slow component (0-400 Hz) and a fast component (400-1500 Hz) by using digital filtering technique. The magnitude of the slow component was little affected with increasing stimulus rate from 8/sec to 90.9/sec, while successive waves of the fast component, including wave V, decreased in amplitude as stimulus rate was increased. The latency of the slow component and each wave of the fast component was prolonged with increasing click rates. The shift of latency became longer in the later waves than in the earlier waves.

Adult↗

PubMed1986

High-performance liquid chromatographic analysis of bacterial fatty acid composition for chemotaxonomic characterization of oral streptococci.

A high-performance liquid chromatographic method was developed to analyze the fatty acid composition of bacterial lipids. After saponification of lipids extracted from bacteria, the liberated fatty acids were labeled with a fluorescence reagent, 4-bromomethyl-7-acetoxycoumarin, followed by reversed-phase high-performance liquid chromatographic separation and fluorescence detection. All bacterial fatty acids were simultaneously separated within 30 min and sensitively determined. This method was applied to the chemotaxonomic characterization of oral streptococci. The fatty acid composition of phospholipids and total lipids distinguished Streptococcus mutans from any other species examined and showed that Streptococcus sanguis had a close taxonomic relationship with Streptococcus salivarius.

Cardiolipins↗

PubMed1986

Interordinal conservatism of chromosome banding patterns in Gallus domesticus (Galliformes) and Melopsittacus undulatus (Psittaciformes).

Chromosome banding homologies were studied between the domestic chicken, Gallus domesticus (Galliformes), and the budgerigar, Melopsittacus undulatus (Psittaciformes). In spite of large karyological differences, the G-banding patterns were found to be conserved to a considerable extent between the two species. There were some differences in C- and Hoechst 33258/Q-banding patterns.

Animals↗

PubMed1986

Pharmacological studies on the anti-inflammatory action of phenolic compounds.

The mechanism of the anti-inflammatory action of phenolic compounds was examined using neutrophil chemotaxis. Chemotactic activity of guinea pig peritoneal neutrophils to N-formylmethionyl-leucylphenylalanine (FMLP) was suppressed in a concentration-dependent manner. The order of drug potency in inhibiting the neutrophil chemotaxis was eugenol much greater than thymol greater than guaiacol much greater than phenol. The concentrations of phenolic compounds used in these experiments did not induce lactate dehydrogenase (LDH) release and did not affect neutrophil viability. There was a consistent positive relation between the ID50 of superoxide anion generation in neutrophils and the inhibitory dose for neutrophil chemotaxis by phenolic compounds. A free phenolic hydroxyl group is essential for scavenging oxygen free-radicals and is also essential for inhibiting leukocyte chemotaxis, as was demonstrated in these experiments. These findings suggest that inhibition of leukocyte chemotaxis may be involved in the anti-inflammatory action of phenolic compounds, and that one of the anti-inflammatory actions of phenolic compounds is the prevention of the production of oxygen free-radicals by leukocytes.

Animals↗

PubMed1986

Variability of direct arterial blood pressure in essential hypertension--relationships between the fall of blood pressure during sleep and awake resting hemodynamic parameters.

The relationship of continuous ambulatory intra-arterial blood pressure over a 24-hour period and awake resting hemodynamic parameters measured by echocardiography was studied in 21 patients with essential hypertension (WHO stage I & II): Left ventricular wall thickness at end-diastole correlated strongly with average SBP and weakly with average DBP during both waking and sleeping periods. Variability of blood pressure taken during waking and sleeping periods was not significantly correlated with any hemodynamic parameters measured by echocardiography. Variability of SBP during sleep had a significant correlation with age; however the fall of blood pressure during sleep had no significant correlation with age. Fall of blood pressure during sleep was significantly correlated to resting awake TPR. In patients with essential hypertension, the above results demonstrate that subjects with thicker left ventricular wall have higher average continuous blood pressure over 24-hours and suggest that there is a tendency for greater falls in blood pressure during sleep to occur in subjects with higher TPR and that older subjects have greater variabilities of SBP during sleep.

Adult↗

PubMed1986

The effect of calcium antagonists on the activation of guinea pig neutrophils.

The role of calcium ions in the activation of guinea pig neutrophil functions was examined by evaluating the effects of calcium antagonists. The data presented here show that calcium antagonists inhibit the activation of guinea pig neutrophil functions elicited by N-formyl-methionyl-leucyl-phenylalanine (FMLP) such as chemotaxis, superoxide anion generation and granule enzyme release in a concentration-dependent manner. The concentrations of calcium antagonists demonstrating the inhibition of neutrophil functions may be somewhat different for each function and higher than that of smooth muscle cells. Calcium ionophore A23187 (A23187) caused superoxide anion generation and granule enzyme release of the neutrophils. A23187 also potentiated the FMLP-induced superoxide anion generation and granule enzyme release of the neutrophils. On the contrary, A23187 neither elicited neutrophil chemotaxis nor affected FMLP-induced neutrophil chemotaxis. These results indicate the possibility that the inhibitory effect of calcium antagonists on the activation of neutrophil functions is probably not simply mediated by inhibition of calcium uptake but also by inhibition of a calcium-dependent intracellular target.

Acetylglucosaminidase↗

PubMed1986

[The effects of low dose DBcAMP on hemodynamics and metabolism in patients following open heart surgery].

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Adolescent↗

PubMed1986

Cytological evidence for single-cell origin of tumors induced with 3-methylcholanthrene in female mice carrying Cattanach's translocation.

Chromosome studies were carried out on 12 tumors induced by subcutaneous injection of 0.005-0.5 mg of 3-methylcholanthrene in female mice carrying Cattanach's X-autosome translocation. Using the asynchronously replicating (hence genetically inactive) X chromosome as a marker, we obtained evidence showing that most or all of these tumors were monoclonal in origin. A single case, in which cell fusion occurred early in tumorigenesis, demonstrated that simultaneous expression of two different X chromosomes is not always incompatible with monoclonality.

Animals↗

PubMed1986