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Biomedical subjects

M Hatano

Publications and source records attributed to M Hatano.

At least 343 records · Page 19Linked to original sources
PubMed1983

Participation of the nucleus locus coeruleus in DOCA-salt hypertensive rats.

The locus coeruleus was subjected to biphasic electrical stimulation, and a group of deoxycorticosterone acetate (DOCA)-salt hypertensive rats revealed a greater pressor response than a group of normotensive control rats. The pressor threshold current (i.e. minimum current to raise the arterial pressure by 10 mm Hg) of DOCA-salt hypertensive rats was also lower. The threshold current was low even in the prehypertensive stage of DOCA-salt treated rats. During arterial pressure fall, the pressor threshold current lowered only in normotensive rats and neither group underwent a change during pressure rise. These data indicated that the locus coeruleus had a pressor role and it had been accelerated in DOCA-salt treated rats before hypertension was evident. Following bilateral electrical lesions of the locus coeruleus no significant differences were observed in the arterial pressure changes, while vascular reactivity to norepinephrine did not differ between the two groups. The results suggest that the locus coeruleus may be involved in the development of hypertension but may not be important in the maintenance of it.

Animals↗
PubMed1983

Interaction of trifluoperazine with porcine calmodulin 19F NMR and induced CD spectral studies.

We have used 19F NMR and CD spectra to study interactions of TFP with CaM under various conditions where no aggregation of TFP occurs. It was found that TFP is bound to CaM in the absence of Ca2+ with Ka greater than 4 X 10(4) M in terms of 19F NMR of TFP and that KCl markedly influences the interaction of TFP with CaM. It was also found that TFP causes quite strong induced CD bands corresponding with the absorption bands of the aromatic ring of TFP when TFP is bound to Ca2+-CaM. The induction of the CD bands was time-dependent and was composed of fast and slow phases.

Animals↗
PubMed1983

Magnetic and natural circular dichroism of L-tryptophan 2,3-dioxygenases and indoleamine 2,3-dioxygenase. I. Spectra of ferric and ferrous high spin forms.

The ferric form of L-tryptophan 2,3-dioxygenases from both Pseudomonas acidovorans (ATCC 11299b) and rat liver showed magnetic CD spectra ascribable to a high spin protohemoprotein at neutral pH, whereas the ferric indoleamine 2,3-dioxygenase from rabbit intestine exhibited a spectrum due to a mixture of high and low spin states under comparable conditions. Upon addition of L-tryptophan, the spectra of the former enzymes changed to another type of high spin spectra, while the latter showed a marked increase in the low spin component. From these findings and effects of pH on the spectra, it is suggested that the sixth ligand of ferric L-tryptophan 2,3-dioxygenases is water at a neutral pH and that for the ferric indoleamine 2,3-dioxygenase is a strong field ligand such as an imidazole nitrogen. The mixed spin state observed for the latter enzyme was ascribable to a thermal equilibrium between high and low spin states as judged by low temperature spectroscopy. With the ferrous form, the Soret magnetic CD spectra of these enzymes were all similar, giving those of a typical high spin ferrous protohemoprotein, whereas visible spectra were different from one another, suggesting differences in the electronic structure of the heme and its vicinity. The natural CD spectra of both ferric and ferrous forms of each enzyme showed negative Cotton effects in the Soret region. Their intensities were different from one another, presumably due to some differences in the interaction of the heme with nearby aromatic amino acid residue(s).

Animals↗
PubMed1983

Decreased colony forming ability of human cells persistently infected with baboon endogenous virus. Brief report.

Plating efficiency (PE), i.e. colony forming ability, of primary human embryonic lung fibroblasts persistently infected with baboon endogenous virus (BaEV) decreased to less than 10 per cent of that of the uninfected cells. A line of human amnion (FL) cells showed a 55 per cent reduction of PE after the establishment of BaEV carrier state. No decrease of PE did occur as a result of BaEV persistent infection in a rhabdomyosarcoma cell line (A204) and in fibroblasts derived from adult human skin. This characteristic reduction of PE in the infected primary embryonic fibroblasts was completely abolished by cultivation of the cells with conditioned medium from confluent either virus-infected or uninfected culture.

Adult↗
PubMed1983

Establishment of Epstein-Barr virus (EBV) infection in epithelial cells derived from the nasopharynx by cell fusion.

To establish EBV-infection in the nasopharyngeal epithelial cells, we carried out cell fusion of the lymphocytes with nasopharyngeal epithelial cells, and proved that it was possible to detect the appearance of EBNA in the epithelial nuclei. It is suggested that the establishment of EBV-infection in nasopharyngeal epithelial cells may include cell fusion and involvement of the EBV receptors.

Antigens, Viral↗
PubMed1983

Plasma cell granuloma of the stomach combined with gastric cancer.

An autopsy case of plasma cell granuloma of the stomach combined with gastric cancer is reported. Plasma cell granuloma presumably occurred independently of adenocarcinoma in the stomach, and nodular or diffuse infiltration of plasma cell containing many Russell bodies was observed in the gastric wall, intermingled with lymphocytes. Infiltrating plasma cells were polyclonal in nature as seen by peculiar meshwork patterns of positive immunofluorescence against human gamma, kappa, and lambda chains. Ultrastructurally, globular Russell bodies, 1-7 micrometers in diameter, were located in the rough endoplasmic reticulum and could be divided into two types, smooth-or rough-surfaced one.

Adenocarcinoma↗
PubMed1983

Impaired cell-mediated immunity in focal glomerular sclerosis.

Cell-mediated immunity (CMI) was evaluated in 8 patients with focal glomerular sclerosis (FGS), 50 patients suffering from chronic mesangial proliferative glomerulonephritis without renal insufficiency and 24 healthy controls. The following parameters were measured: delayed skin reactivity to purified protein derivative, circulating lymphocytes, lymphocyte cell-surface markers (neuraminidase-treated sheep erythrocyte and erythrocyte-antibody-complement rosettes) and functional markers (mitogenic responses to concanavalin A and phytohemagglutinin). The FGS patients with nephrotic syndrome (NS) had a significant depression in CMI, characterized by decreased responses of the lymphocytes to both concanavalin A and phytohemagglutinin, impaired delayed hypersensitivity to purified protein derivative and a decreased proportion of T lymphocytes as compared with normal subjects. In contrast, the levels of all CMI parameters studied in FGS patients in remission and in patients with chronic glomerulonephritis with or without NS did not differ from normal subjects. Thus, the majority of FGS patients with NS demonstrated an impaired response in a CMI assay system. The possible significance of these phenomena in the pathophysiology of FGS is discussed.

Adolescent↗
PubMed1983

Cardiac involvement in mucolipidosis. Importance of non-invasive studies for detection of cardiac abnormalities.

Although mucolipidosis, a fatal metabolic storage disorder, is associated with cardiovascular abnormalities, detailed, non-invasive cardiac examinations have not been well documented. We studied 4 children with type II and type III mucolipidosis, 3 of whom had unequivocal evidence of aortic regurgitation characterized by phonocardiography and M-mode echocardiography. Two-dimensional echocardiography showed an aortic valve prolapse in 3, a mitral valve prolapse in 2 and a tricuspid valve prolapse in 1. The QT interval was prolonged in 2 cases. In 1 autopsy case, we found considerably thickened and retracted aortic, mitral, and tricuspid valves, and accumulation of the foam cells in the myocardium. Echocardiography revealed similar findings in another 3 cases. We conclude that cardiac manifestations in this disorder should be examined carefully particularly by the use of echocardiography which is an excellent technique for detecting cardiovascular abnormalities in mucolipidosis.

Adolescent↗
PubMed1983

The effects of lidocaine and verapamil on overdrive-induced suppression of pacemakers in dogs with complete atrioventricular block.

When the ventricle is electrically stimulated at a faster rate, the cessation of the drive is followed by a temporary suppression of automaticity (overdrive suppression). The effects of lidocaine and verapamil on overdrive suppression were studied in dogs. Lidocaine slowed the ventricular escape rate and prolonged the pause following overdrive; occasionally, it was about twice the next succeeding RR interval. On the contrary, verapamil influenced neither the ventricular escape rate nor the pause following overdrive. It is suggested that lidocaine not only suppresses the automaticity of ventricular escape pacemaker but also induces exit block and that the spontaneous depolarization of the ventricular pacemaker is not slow channel-dependent.

Animals↗
PubMed1983

Influence of food on the clinical effect of angiotensin I converting enzyme inhibitor (SQ 14,225).

In order to clarify the influence of food on the clinical effect of angiotensin I converting enzyme inhibitor (SQ 14,225, captopril), 25 mg of the drug was administered to patients with hypertension using in a two-way crossover study design. In the first study (study I), each subject received the drug 30 min after breakfast, and changes in blood pressure (BP), blood concentration of captopril (BCC), plasma renin activity (PRA), plasma aldosterone (PA) and plasma angiotensin I converting enzyme activity (ACE-A) were determined for 3 hr. BP was recorded for 6 hr. Four days after study I, the same subjects received the drug 2 hr after breakfast, and each parameter was again determined (study II), similarly to study I. No significant difference in the hypotensive responses to captopril was observed between both studies during 6 hr of observation. Maximum hypotensive effects were found within 90 min of the treatments in study I and study II, and BP returned almost to baseline levels at 6 hr in both studies. Maximum BCC levels were found 60 and 90 min after the drug administration in studies I and II, respectively, and these approximated to half of each maximum level at 180 min. There were no statistically significant differences in the biological half-life (T1/2), maximum concentration (C max), maximum concentration time (T max), and area under the blood concentration curve [AUC]0(3) between both studies. The peak in PRA occurred at 60 and 90 min after the administration of the drug in studies I and II, respectively. In study I, a slightly greater reduction of PA levels was found, but there was no significant difference in the magnitude of the reduction between both studies. The present results indicate that food did not exert any significant influence on the clinical effect of captopril.

Adult↗
PubMed1983

[Experimental studies on the genesis of low-frequency vibrations (M-sound) of the first heart sound using a miniature accelerometer].

We studied eight mongrel dogs, weighing 15 to 35 kg, in which an initial low-frequency vibration of the first heart sound (M-sound) was recognized on the chest wall. A miniature accelerometer weighing 0.5 gm was used to record surface velocity signals and surface acceleration signals as well as phonocardiograms over the cardiac apex of the closed chest wall and over the pericardium or epicardium. The frequency response of accelerometer was essentially flat (+/- 1.5 dB) from 1 to 200 Hz. The accelerometer mounted was such that its sensitive axis was perpendicular to the recording surface. Equisensitive phonocardiograms were obtained to compare the signal size of M-sound on the epicardium at several positions including the cardiac apex, the left ventricular anterior wall near the interventricular septum, the left ventricular antero-lateral wall and the right ventricular anterior wall. Intraventricular phonocardiograms and pressure curves were obtained by a Millar catheter directly inserted through the left ventricular wall near the apex to keep the tip near the apex. Furthermore, the relationship between M-sound and the shortening of the myocardium at the apex was investigated by means of ultrasonic dimension system and phonocardiography. Studies of M-sound were performed not only in sinus rhythm, but also in atrio-ventricular dissociation and ventricular pacing after crushing sinus node or electrical vagus stimulation. The results were as follows: The M-sounds over the chest wall, pericardium and epicardium were recorded coincidentally with the onsets of the left ventricular pressure curve, its dP/dt, low-frequency vibration of the first heart sound of intraventricular phonocardiogram, positive velocity, and acceleration of myocardial surface. The M-sound on the epicardium was maximal in intensity at or near the cardiac apex, in comparison with those recorded on the left ventricular anterior wall near the interventricular septum, left ventricular antero-lateral wall, and right ventricular anterior wall. The M-sound was observed between A and C points of the mitral valve echogram. There was no effect of atrial contraction on the M-sound in cases of atrio-ventricular dissociation. The onset of the M-sound on the epicardium at the apex was not always coincident with the onset of shortening of the myocardium at the same position.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗