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S Chihara

Publications and source records attributed to S Chihara.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Prediction of survival of terminally ill cancer patients--a prospective study].

Planning effective palliative care requires accurate estimation of survival. A prospective study was performed on 150 hospice inpatients to identify prognostic factors in terminally ill cancer patients. By univariate analysis, eleven factors were found to be significantly associated with shortened survival: poor performance status, dyspnea at rest, death rattle, appetite loss, dysphagia, dry mouth, general malaise, edema, stomatitis, fever, and delirium. Multiple regression analysis showed that five factors were independent predictors of survival: performance status, dyspnea at rest, appetite loss, edema, and delirium. We discussed current problems and future directions of survival prediction for terminally ill cancer patients.

Activities of Daily Living↗
PubMed1997

Consequences of metabolic inhibition in smooth muscle isolated from guinea-pig stomach.

1. In smooth muscle isolated from the guinea-pig stomach, cyanide (CN) and iodoacetic acid (IAA) were applied to block oxidative phosphorylation and glycolysis, respectively. Effects of IAA on generation of spontaneous mechanical and electrical activities were systematically investigated by comparing those of CN. Spontaneous activity ceased in 10-20 min during applications of 1 mM IAA. On the other hand, application of 1 mM CN also reduced the spontaneous activity, but never terminated it. In the presence of CN the negativity of the resting membrane potential was slightly reduced. 2. When spontaneous activity ceased with IAA, the resting membrane potential was not significantly affected. Also, before ceasing, the amplitude and duration of the spontaneous electrical activity were significantly reduced. The amplitude of the electrotonic potential was, however, not changed by IAA. Further, glibenclamide did not prevent the effects of IAA. These results suggest that, unlike cardiac muscle, activation of metabolism-dependent K+ channels in stomach smooth muscle does not seem to play a major role in reducing and terminating spontaneous activity during metabolic inhibition. 3. Carbachol-induced contraction transiently increased, and subsequently decreased gradually during application of IAA. 4. After 50 min application of IAA, when there was no spontaneous activity, the concentrations of phosphocreatine (PCr) and ATP measured with 31P nuclear magnetic resonance decreased to 60 and 80% of the control, respectively, while inorganic phosphate (Pi) concentration paradoxically fell to below detectable levels. During subsequent prolonged application of IAA, high-energy phosphates steadily decreased. On the other hand, after 50 min CN application, [PCr] and [ATP] decreased to approximately 30 and 80% of the control, respectively, while [Pi] increased by 2.6-fold. 5. In the presence of either CN or IAA, spontaneous mechanical and electrical activities were reduced or eliminated, although amounts of high-energy phosphates sufficient to contract smooth muscle remained. It can be postulated that some mechanism(s) related to energy metabolism, but not including ATP-sensitive K+ channels, plays an important role in generating spontaneous activity in guinea-pig stomach smooth muscle. During metabolic inhibition the energy metabolism-dependent mechanism(s) would preserve high-energy phosphates, and consequently cell viability, by stopping spontaneous activity.

Adenosine Triphosphate↗
PubMed1996

Sedation for symptom control in Japan: the importance of intermittent use and communication with family members.

We reviewed the circumstances surrounding the use of sedation for symptom control in a Japanese hospice. Of 143 inpatients, 69 (48.3%) received sedation and died an average 3.9 days after sedation was begun. Symptoms requiring sedation included dyspnea, pain, general malaise, agitation, and nausea. In 83% of cases, those symptoms were escalating as death approached. In about one-half of the cases, sedation was carried out intermittently until the patient died. Sedation was gained by such sedatives as midazolam, morphine, and haloperidol. Side effects included suppression of the respiratory and/or circulatory system in nine cases (in four cases it caused death), and delirium in one case; tolerance and dependence were also observed in two cases. We also examined the explanation to and understanding of the patients and their family members about sedation. This experience suggested the type of communication methods that are likely to be useful in Japan. It stresses the importance of intermittent use of sedation and communication with family members. We propose criteria for sedation to improve symptom control that would be acceptable in Japan.

Aged↗
PubMed1993

Effects of quinotolast, a new orally active antiallergic drug, on experimental allergic models.

The effects of a new antiallergic drug, quinotolast [sodium 5-(4-oxo-1-phenoxy-4H-quinolizine-3-carboxamido)tetrazolate monohydrate], were studied and compared with those of tranilast, amlexanox, pemirolast, repirinast and disodium cromoglycate (DSCG) in experimental allergic models. Quinotolast potently inhibited such type I allergic reactions as passive cutaneous anaphylaxis (PCA) and anaphylactic bronchoconstriction in rats by both intravenous and oral dosing. All of these effects were stronger than those of the reference drugs tested. Quinotolast inhibited histamine release from rat peritoneal cells, but it had no antagonistic effect on histamine-, serotonin-, platelet activating factor- or bradykinin-induced cutaneous reactions in rats. Moreover, it was clearly demonstrated that quinotolast and DSCG had a cross tachyphylaxis to inhibit PCA in rats, suggesting that these drugs, at least in part, share the same mechanism of action. Furthermore, quinotolast potently inhibited PCA in guinea pigs in which DSCG and other reference drugs showed poor inhibitory activity. Quinotolast also showed stronger inhibitory effects on histamine and peptide leukotrienes release from guinea pig lung fragments or mouse cultured mast cells than the other drugs tested. Thus, the effect of quinotolast on type I allergic reaction would seem to be based on an inhibition of mediator release from inflammatory cells including mast cells. The results suggest that quinotolast will be beneficial in the treatment of type I allergy-related diseases.

Administration, Oral↗
PubMed1991

[The role of hospice in Japan].

It was more than 15 years ago that the concept of Hospice Care was introduced to Japan through the activity of St. Christopher's Hospice established in London, 1967. At that time medico-social circumstances in our country were not necessarily desirable for both doctors and patients, especially for terminally ill cancer patients. In this paper, some factors spoiling the good relationships between doctors and patients will be analyzed and the importance of Hospice in our country will be explained based on the 10 years' practice and experience at Seirei Hospice. Moreover, some details on how to take care of terminally ill cancer patients will be mentioned. Conclusively, it should be emphasised that the special department of terminal care medicine for cancer patients must be organized, and the appearance of doctors who devotedly attend to the practical activity for terminal care is heartly expected.

Hospices↗
PubMed1989

Dynamic aspects of airborne bacterial flora over an experimental area in a suburb and distribution of resistant strains to antibacterial agents among airborne staphylococci.

Airborne bacterial floras were investigated at stations A to E and P on the UOEH campus located in a suburb of the city of Kitakyushu. Bacterial collections were carried out by a filtration method using a soluble gelatin foam filter at an altitude of 1 m from the ground and viable bacterial cells were enumerated on nutrient agar plates supplemented with 50 micrograms/ml cycloheximide. At station P, where airborne bacterial composition was evaluated as a mean value of 20 repeated experiments, there were 42% Gram-positive cocci, 37% Gram-positive rods, 3.5% Bacillus strains and 5.5% Gram-negative rods. Fluctuating values of cell amounts for Gram-positive cocci and rods during these experiments suggested that in the atmospheric layer near the ground, the former was a more transient group of airborne bacteria than the latter. When airborne bacterial flora over the experimental area was surveyed by observations at six stations, the dispersion profile of bacterial flora closely corresponded to vegetating states on the surface of the ground. Over vegetating areas, airborne bacterial flora appeared in about equal amounts of Gram-positive rods and cocci, while over bare ground, Gram-positive rods appeared more abundantly than Gram-positive cocci. To investigate the distribution of drug-resistant strains among airborne bacteria, sensitivity tests to six antibiotics were carried out with S. xylosus strains isolated at stations P and E. As a result, considerable amounts of single-drug-resistant strains for TC (DOX) and EM were recognized, but the distribution of multiple-drug-resistant S. xylosus was restricted to a few strains.

Air Microbiology↗
PubMed1989

[The role of radiotherapy in hospice care].

The aim of palliative radiotherapy for the terminally ill is to improve the quality of the remaining span of life. From November 1982 to September 1987, 69 patients in the Seirei Hospice have been treated with such radiotherapy, and symptomatic relief was obtained in 64% of these patients. Radiotherapy also proved useful in achieving an improvement in their performance status. While the aim of hospice care is not directed towards treatment of the underlying disease, the use of radiotherapy is considered to have an important role in hospice care.

Hospices↗
PubMed1989

[Hospice].

Terminal care for cancer patients must be oriented to the dignity of human being. For this purpose our hospice has five principles, that is, to control physical pain, to relieve spiritual problems, to settle socio-economical matters, to give religious support and lighten family loads. To put into practice these five principles, various kinds of staff take their places as caregivers: physicians, nurses, helpers, chaplains, psychiatrists and voluntary workers. Moreover, the Hospice has many facilities such as a community hall, a kitchen for family members, guestrooms for family members and friends, a chapel for services and patient's rooms with one bed which make it possible for the patients to communicate intimately with family members or friends. During these 7 years, from April '81 to March '88, 398 terminally ill cancer patients have been treated at the Seirei Hospice. Through these experience, we have observed that most of terminally ill cancer patients do wish to live as long as possible in good condition without physical pain. So, we should conclusively emphasize that medical treatment including radiotherapy and cancer chemotherapy, attempting to reduce the physical distresses, ought to be continued until the time when the treatment might come to waste the patient's energy and only increase their agony.

Adolescent↗
PubMed1988

Frequency and voltage dependent effects of AN-132, a new class I anti-arrhythmic agent, on Vmax of action potential upstroke in guinea pig ventricular muscles.

The in vitro electrophysiological properties of a newly synthesised antiarrhythmic agent, AN-132, were evaluated by recording transmembrane action potentials from guinea pig papillary muscles. AN-132 (10-100 mumol.litre-1) caused a dose dependent decrease in the maximum upstroke velocity (Vmax) of the action potential without affecting the resting potential. In the presence of AN-132, trains of stimuli at rates greater than or equal to 0.1 Hz led to an exponential decline in Vmax. This use dependent block was enhanced at higher stimulation frequency. The time constant for the recovery of Vmax from the use dependent block was 39.5-41.2 s. The curves relating membrane potential and Vmax were shifted by AN-132 (100 mumol.litre-1) in the direction of more negative potentials (6.1 mV). In preparations treated with AN-132 (30 and 100 mumol.litre-1), the Vmax of test action potentials preceded by conditioning clamp pulses to 0 mV was progressively decreased with an increasing number of pulses. A single prolonged clamp pulse to 0 mV reduced Vmax much less than multiple brief clamp pulses. These findings suggest than AN-132 has use dependent inhibitory action on the fast sodium channel by binding to the channel mainly during its activated state and that the unbinding rate of the drug during diastole is very slow. This use dependency and its greater inhibition of Vmax in depolarised muscles through the increase in tonic block may play a major role in preventing ventricular arrhythmias.

Action Potentials↗
PubMed1987

Mechanical and electrical responses to alpha-adrenoceptor activation in the circular muscle of guinea-pig stomach.

1 In the circular muscle of the corpus region of the guinea-pig stomach, the effects of catecholamines on mechanical activity were studied with simultaneous recording of membrane potential by use of intracellular microelectrodes. In order to investigate responses mediated through alpha-adrenoceptors, the beta-adrenoceptors were blocked by propranolol (10(-6) M) in most experiments. 2 Adrenaline (less than 10(-6) M) produced a monophasic contraction with little change in membrane potential. At higher concentrations (greater than 10(-5) M), adrenaline usually produced an early transient contraction followed by a slow tonic contraction. During the early phase, the membrane was hyperpolarized and slow waves were reduced in amplitude. 3 The phasic contractions superimposed on the late slow phase of the contractile response were higher in frequency and larger in amplitude than in controls before adrenaline application. These changes were associated with an increase in the amplitude and frequency of slow waves, and with a spike-like component appearing on the top of each slow wave. 4 Adrenaline-induced changes in mechanical and electrical activity were inhibited by prazosin, but largely unaffected by yohimbine. In some preparations, there was a transient weak inhibition of phasic contraction before muscle tone was increased by adrenaline, and this became more pronounced in the presence of yohimbine. 5 Phenylephrine, selective for alpha 1-receptors, produced responses very similar to those of adrenaline, whereas agonists selective for alpha 2-receptors, clonidine and B-HT 920, produced only a small slow contraction without any clear change in membrane potential. 6 It is concluded that in the circular muscle of guinea-pig stomach, the contractile response and changes in the electrical slow wave activity produced by adrenaline are both mediated mainly through the activation of alpha-receptors.

Adrenergic alpha-Agonists↗
PubMed1985

[Drug susceptibility of staphylococci isolated from clinical specimens].

Eighty-eight strains of staphylococci were isolated from a variety of specimens collected from patients at our university hospital from June to August 1982. These strains were identified as Staphylococcus aureus (86%), Staphylococcus epidermidis (6.8%), Staphylococcus haemolyticus (2.3%), Staphylococcus capitis (2.3%), and Staphylococcus simulans (1.1%). One strain could not be identified with certainty as a currently recognized species. A majority (70%) of the S. aureus strains was resistant to two or more of the following drugs; penicillin G, kanamycin, doxycycline, erythromycin, and chloramphenicol. As for susceptibility to beta-lactam antibiotics, most of the strains that were resistant to penicillin G were also resistant to aminobenzyl penicillin and cephalexin. Whereas none of the strains was resistant to methicillin, cloxacillin, dicloxacillin, nor cefmetazole, and only a few strains were resistant to cefoperazone or cefazolin or both. Over 50% of the S. aureus strains were found to be resistant to each of four aminoglycosides (Kanamycin, gentamicin, tobramycin, and sagamicin), while only 5% of the strains were resistant to amikacin. Multiple resistance to the above four aminoglycosides was observed among more than 40% of the S. aureus strains, and also observed among three of six strains of S. epidermidis.

Aminoglycosides↗
PubMed1985

Effects of an indazole derivative, FKK, a novel bronchodilator, on the cardiovascular system in dogs.

The cardiovascular effects of FKK (2,3-dihydro-7-methyl-9-phenyl-1H-pyrazolo [1,2-a]indazolium bromide) were compared with those of aminophylline and isoproterenol in anesthetized dogs. The doses of the three drugs used were sufficient to cause significant tracheal dilation in the anesthetized dogs. FKK (0.1-3.0 mg/kg, i.v.) slightly increased respiratory frequency, left ventricular (LV) dp/dt max and myocardial contractile force. A slight increase followed by a decrease was observed in systemic blood pressure and LV systolic pressure. The drug caused direct vasodilation in the coronary, mesenteric and femoral vasculatures, but had no effect on the renal vasculature. Similar results were obtained with aminophylline (0.3-30.0 mg/kg, i.v.) and isoproterenol (0.003-0.3 microgram/kg, i.v.), but their effects on the measured cardiac parameters were much more potent and long-lasting than those of FKK, when compared in doses producing a bronchodilation in similar magnitude. It is particularly pertinent that FKK (30 mg/kg, i.d., enough to cause marked bronchodilation), unlike aminophylline (30 mg/kg, i.d.), did not significantly influence the cardiovascular system.

Aminophylline↗
PubMed1984

[Mutagenesis of amino and/or methyl analogs of acridine in Salmonella and yeast: a comparison between the spot-test and the pre-incubation methods].

The relationship between mutagenic activities and chemical structure of acridine derivatives was examined by using Salmonella typhimurium strains TA 1537 and TA 1977 and yeast Saccharomyces cerevisiae. Most analogs with amino and/or methyl group(s) caused frameshift-type mutation in Salmonella without mammalian microsomal enzyme activation. The 9-amino analogs were strong mutagens and mutagenicity was also increased when 10-position was methylated in 1-amino and 2-amino compounds. However, 9-amino derivatives did not cause mitochondrial mutation in yeast, where 3,6-diamino and/or 10-methyl groups were structural requisites for significant mutagenic activity. In comparison with the pre-incubation method, the spot-test method was shown to be less sensitive. The mutagenicity of some compounds could not be detected by the spot-test method. Mutagenic activities of these drugs were revealed and increased markedly with an increase in pre-incubation period up to 20 min, suggesting that the pre-incubation of tester bacteria with a compound prior to a mutagenicity assay is necessary for the detection of mutagenesis of these compounds.

Acridines↗
PubMed1984

Action of the Na+ ionophore monensin on vascular smooth muscle of guinea-pig aorta.

The effects of the Na+ ionophore monensin on contractile responses were investigated in guinea-pig aorta in normal and high K+ solutions. In normal K+ (5.4 mM) solution, monensin (2 X 10(-5) M) produced a rapid increase in tension followed by slow relaxation. This contraction was markedly inhibited by phentolamine (10(-5) M) or prazosin (10(-6) M) and was accompanied by an increase in tritium efflux from tissue preloaded with [3H]norepinephrine. In the presence of phentolamine, monensin (1-2 X 10(-5) M) or ouabain (1-2 X 10(-5) M) caused only a small and slowly developing contraction. Simultaneous application of these agents caused a more rapid and greater contraction. Either monensin or ouabain gradually increased cellular Na+ and decreased cellular K+ content. When monensin was applied simultaneously with ouabain, there was a rapid increase in cellular Na+ and loss of cellular K+. In high K+ (65.4 mM) solution, monensin (10(-6) M) slightly reduced the increased tension level but when external glucose was omitted monensin markedly inhibited the contraction. A significant decrease in tissue ATP content was observed only when monensin was applied in glucose-free solution. Similarly, hypoxia (N2 bubbling) markedly inhibited the high K+ contraction and decreased the tissue ATP content only in the absence of glucose. These results suggest that monensin produces a neurogenic contraction due to the release of endogenous catecholamines and also produces a myogenic contraction by a decrease in transmembrane Na+ and K+ gradients when the Na+-K+ pump is inhibited by ouabain, and that monensin inhibits aerobic energy metabolism of vascular smooth muscle.

Adenosine Triphosphate↗