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Biomedical subjects

H Harada

Publications and source records attributed to H Harada.

At least 631 records · Page 35Linked to original sources
PubMed1984

Beneficial effect of taurine on congestive heart failure induced by chronic aortic regurgitation in rabbits.

Taurine (2-aminoethanesulfonic acid) is known to have a cardiotonic action. The present study was designed to see whether oral treatment with taurine could improve the status of congestive heart failure induced by aortic regurgitation. Nine rabbits were treated daily with taurine (100 mg/kg) after producing aortic regurgitation. Cumulative mortality at 8 weeks in the non-treated group was 52% compared with 11% in the taurine-treated group (p less than 0.05). Cardiac function (max dP/dt) was significantly decreased in rabbits with aortic regurgitation, whereas in taurine-treated rabbits, cardiac function was maintained the same as control. The present data suggest that taurine prevented the rapid progress of heart failure, and consequently prolonged the life expectancy.

Animals↗
PubMed1984

[Clinical experience with methylcobalamin (CH3-B12) for male infertility].

CH3-B12 was administered daily (1,500 micrograms/day, for 4 to 24 weeks) to 26 infertile male patients who visited our clinic from January to December, 1982. It was not administered, however, to patients with azoospermia. Semen analysis was conducted from 8 weeks after the administration of CH3-B12. Sperm concentration increased in 10 cases (38.4%), total sperm counts increased in 14 cases (53.8%), sperm motility increased in 13 cases (50.0%) and total motile sperm count increased in 13 cases (50.0%). Semen volume, however, could not be evaluated due to wide variation. Serum LH, FSH and testosterone were unchanged. Judging by our criteria, 11 cases (42.3%) improved, 11 cases (42.3%) were unchanged and the remaining 4 cases (15.4%) had aggravated.

Adult↗
PubMed1984

[Clinical and statistical studies on male infertility and follow-up studies for pregnancy (II)].

Clinical and statistical studies were carried out on 369 infertile male patients who are increasing year by year visiting our clinic during the 3 years from January 1978 to December 1980. If divided into 5-year age groups, the highest frequency occurred in the 30 to 34 year-old age group. In the semen analysis, 23.8% of the patients showed azoospermia, and 48.5% oligozoospermia; the testicular volumes of these patients was generally small. Pathological examinations of their testis revealed germinal cell aplasia or hypospermatogenesis. In the hormonal examinations performed, serum LH and FSH levels in azoospermic and oligozoospermic patients showed a tendency to be higher than normal. Follow-up studies for pregnancy were performed on 242 cases. Among the 108 cases which we were able to study, 30 cases were able to give successful pregnancy, 17 of whom had been treated by clomiphene citrate, 2 by testosterone-clomiphene therapy, and 11 were untreated.

Adult↗
PubMed1983

Isolation of Ia positive human leukocytes by a direct rosette assay.

A direct rosette assay (DRA) using ox erythrocytes coated with monoclonal antibody (AF-10) to human Ia-like antigen (OE-anti-Ia) is a rapid and convenient method for detection and isolation of Ia-like antigen-bearing cells. Various cell lines and peripheral blood lymphocytes were tested by DRA. Cell lines expressing Ia-like antigen formed rosettes, while cell lines lacking Ia-like antigen did not. In a highly purified T cell fraction, a small number of T cells formed rosettes; but in a Con A-stimulated T cell fraction, about 40% of the cells formed rosettes. The majority of purified B cells and monocytes formed rosettes. Rosette-forming and non-rosette-forming mononuclear cells could be separated by centrifugation on Ficoll-Urografin. Rosette-forming cells reacted positively by indirect immunofluorescence (IIF), while non-rosette-forming cells reacted negatively. The results obtained by DRA were consistent with those obtained by IIF with OKIa*1 and AF-10. DRA is thus suitable not only for detection of Ia-like antigen-bearing cells, but also for separation of Ia-like antigen-positive (Ia+) and -negative (Ia-) cells.

Animals↗
PubMed1983

Epidemiology of Parkinson's disease in a Japanese city.

A study of the incidence of Parkinson's disease was carried out in a Japanese city, and cases of those who had died were studied to clarify the longevity of the patients and causes of death. On incidence day, April 1, 1980, a total of 101 patients with Parkinson's disease were found to be living in the investigated area, which had a population of 125,291. The incidence rate was 80.6 per 100,000 population, and the average annual incidence for the period 1975 through 1979 was 10.2 per 100,000 population per year. The average age at death was 70.0 years, and the mean duration of illness was 7.4 years. The main causes of death were heart diseases and bronchopneumonia, which were complications of a long period of being bedridden.

Adult↗
PubMed1983

Alteration of strial capillary transport in kanamycin-treated guinea pigs.

Ferritin transport through the strial capillary during kanamycin intoxication was examined under a transmission electron microscope. Twelve guinea pigs were treated intramuscularly with kanamycin (400 mg/kg/day) for 2-3 weeks. When full hearing loss was recognized by estimating the Preyer reflex or auditory brain-stem response (ABR), ferritin was given intravenously and animals were sacrificed 1/3, 1, and 2 h later. At 1/3 h, ferritin was present diffusely not only in the endothelial cell but also in the basal lamina and within vesicles in the strial cell. Alternatively, it was discharged into the endolymphatic space. At 2 h, ferritin was seen on the luminal surface and in the cytoplasm of the endolymphatic cells of Reissner's membrane. These results suggest that the basal lamina of the strial capillary was altered qualitatively by kanamycin administration.

Animals↗
PubMed1983

The fine structure of pancreatic stones as shown by scanning electron microscopy and X-ray probe microanalyser.

To delineate the process of pancreatic stone formation, stones from four patients were studied with a scanning electron microscope and X-ray probe microanalyser. The stones consisted of a central core and surrounding shell. Two kinds of stones were demonstrated: one had a core composed of a calcium-rich amorphous substance and interlacing fibrils; the other had a core consisting of multiple cavities with smooth walls composed of a calcium-deficient amorphous substance. The shells showed a common structure: zones of layers or bands of a calcium-rich amorphous substance, network fibrils filled with a calcium-rich amorphous substance, and laminated parallelogrammic or polygonal plates of calcite parallel to the surface in one layer and oblique or perpendicular in the next layer. Calcium was in the crypto-crystalline state as well as crystalline state of calcite. Crystalline calcite showed spiral and epitaxial growth along with findings of dissolution, resembling cholesterol crystals of gall stones. Pancreatic stones are probably formed through central core formation and layered growth of a shell. Comparison of stones and protein plugs suggests that protein plugs can grow to stones with calcite deposition accompanied by precipitation of network fibrils and an amorphous substance.

Bacteria↗
PubMed1983

Concentration-dependent effect of trapidil on slow action potentials in cardiac muscle.

Trapidil, a coronary vasodilator and positive inotropic agent, was tested for its ability to affect the normal "fast" action potentials and the "slow" action potentials and contractions of isolated perfused chick hearts, and to affect the tissue cyclic AMP level. At 5 X 10(-3) M, trapidil completely blocked the fast Na+ channels in hearts perfused with normal Tyrode solution, since this dose abolished the action potential when verapamil (2 X 10(-6) M) was present to eliminate the inward slow current. To study effects on the slow channels, the fast Na+ channels were voltage-inactivated by partial depolarization to about -40 mV with an elevated (25 mM) K+-Tyrode solution, resulting in loss of excitability. At low concentrations (1 X 10(-4) - 1 X 10(-3) M), trapidil induced slow action potentials accompanied by contractions, even in the presence of a beta-adrenergic blocker. In contrast, at high concentrations (3 X 10(-3) - 1 X 10(-2) M), trapidil markedly depressed or blocked the isoproterenol-induced slow action potentials. Consistent with this dual action, in hearts perfused with normal Tyrode solution, trapidil exerted a small positive inotropic action at low doses and a considerable negative inotropic action at high doses, even though the intracellular cyclic AMP level was substantially elevated. That is, trapidil has actions similar to those of papaverine. It is concluded that trapidil blocks both fast Na+ channels and slow channels in cardiac muscle, the fast Na+ channels being more sensitive, and that low concentrations of trapidil induce slow channels by elevating the cyclic AMP level because of phosphodiesterase inhibition.

Action Potentials↗
PubMed1983

Protection by oral pretreatment with taurine against the negative inotropic effects of low-calcium medium on isolated perfused chick heart.

Chicks were given taurine by mouth using a cannula pushed down into the oesophagus. This treatment had protected the heart, when subsequently removed, against the decline of contractile force in the perfused heart brought about by low-calcium media. A small but statistically significant increase in taurine concentration occurred in the ventricular tissue of such pretreated hearts. In contrast, pretreatment with taurine did not affect ventricular calcium level. Addition of taurine (3 to 100 mmol . litre-1) into the perfusing solution did not alter the cyclic AMP level in the control perfused hearts, and failed to induce slow channel action potentials in hearts whose fast Na+ channels had been inactivated by high K+ (25 mmol . litre-1). However, taurine perfusion produced a significant positive inotropic action which became stable after 5 to 10 min of exposure.

Administration, Oral↗
PubMed1983

Histochemical studies on enzyme-digested protein plugs of patients with chronic pancreatitis: a preliminary report.

Sulfated acidic mucopolysaccharides have been found to be significant components of "protein plugs" in patients with chronic pancreatitis. The precise identification of the mucopolysaccharides and their distribution within the protein plugs may clarify the pathogenesis of the plugs. Pure pancreatic juice from five patients with chronic pancreatitis was obtained by endoscopic retrograde catheterization of the papilla of Vater. Enzymes for digestion of the plugs included hyaluronidase of the bovine testes and streptomyces hyalurolyticus, chondroitinase ABC and AC, and sialidase (neuraminidase). Our study indicated that: I) Sialic acid is distributed throughout the plugs and may be a major component, followed by a lesser amount of chondroitin sulfate B. 2) Chondroitin sulfate A, C, D and E and chondroitin may be minor components. 3) Hyaluronic acid is negligible in the plugs.

Chronic Disease↗
PubMed1983

Enhancement of EEG spikes and hyperpolarizations of pyramidal cells in the kindled hippocampus of the rabbit.

EEG spikes and their intracellular correlates were studied in both normal and kindled hippocampi (i.e., the hippocampi subjected to daily electrical stimulation) of rabbits. Many of the EEG spikes observed were referred to as inhibitory EEG spikes, because their intracellular correlates were hyperpolarizations of pyramidal cells. In most cases, these hyperpolarizations occurred without any preceding spikes, but could be led by a single spike. They were, however, never preceded by a spike burst. Inhibitory EEG spikes occurred in both normal and kindled hippocampi. In both cases, they not only appeared spontaneously, but were also induced by brain stem stimulation. Regardless of whether they appeared spontaneously or were induced by stimulation, the inhibitory EEG spikes and the corresponding hyperpolarizations were much larger in magnitude in the kindled than in the normal hippocampus. Consequently, it was concluded that enhancement of inhibition was one of the features of the kindled hippocampus.

Animals↗
PubMed1983

Enhancement of ciliary action by a beta-adrenergic stimulant.

It is known that beta-adrenergic stimulants enhance mucociliary transport in the respiratory tract. The present study clearly indicated that such an enhancement resulted from not only the alteration in secretory function but also the direct stimulation of ciliated cells. However, the enhancement of ciliary beating depended on the morphological changes in ciliated cells. On the other hand, the effect of terbutaline aerosol, a beta-adrenergic stimulant, on patients with chronic sinusitis was evaluated by paranasal sinus radiography. Consequently, marked improvements in shadows were achieved after 4 weeks in 40% of the cases examined.

Adult↗