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Biomedical subjects

T Hata

Publications and source records attributed to T Hata.

At least 307 records · Page 17Linked to original sources
PubMed1994

[Immunocytochemistry in the diagnosis of acute myeloid leukemia (M0)].

We examined leukemic blasts from 5 cases of AML-M0 diagnosed according to The French-American-British (FAB) classification for expression of immunological markers as well as myeloperoxidase (MPO) using flow cytometry (FCM) and immunocytochemistry (ICC). In one patient, the myeloid antigens, CD13 and CD33, were negative on FCM, but apparently positive in the cytoplasm by ICC, leading to a diagnosis of AML-M0. We examined MPO with anti-MPO monoclonal antibody in four patients by ICC, and could detect 3% or more MPO positive rates in all cases. These findings indicate that immunological studies for MPO and myeloid markers using ICC are very useful for the diagnosis of AML-M0. Two of 5 patients achieved CR, but they relapsed soon or after one year, respectively. The treatment outcomes suggest that the AML-M0 is an AML subtype with poor prognosis.

Adolescent↗
PubMed1994

Interaction of renal excretion between nilvadipine metabolites, M3 and M7 in rats: characterization of sex-dependent and sex-independent active secretion in the kidney.

The interaction of renal clearance between nilvadipine metabolites, M3 and M7, in male and female rats including protein binding and renal excretion was investigated to clarify the mechanisms involved. In male rats, active renal secretion of M7 (the 5-carboxylic acid pyridine derivative) was reduced in inverse proportion to the molar ratio of the plasma concentration M3/M7 after an i.v. dose of M3 (the 3-carboxylic acid pyridine derivative), and the dosed M3 was excreted only by glomerular filtration. In female rats, the active renal secretion of M7 was unaffected after an i.v. dose of M3, and the dosed M3 was excreted by active secretion. These results indicate an interference of the active secretion of M7 in male rats by M3 on competitive interaction at the renal tubular secretion, even though M3 was excreted only via a filtration process. Female rats may have two distinct and separate active renal secretion mechanisms for M7 and M3, even though these carboxylic acid compounds were eliminated by active transport in the kidney.

Animals↗
PubMed1994

Long-term therapy with terazosin may improve glucose and lipid metabolism in hypertensives: a multicenter prospective study.

The effects of long-term monotherapy with terazosin, an alpha-1 blocker, on blood pressure, glucose tolerance, and serum lipid profiles were prospectively investigated in 53 hypertensive patients: 19 with normal glucose tolerance (NGT) and 34 with impaired glucose tolerance (IGT). The plasma glucose, serum lipids, fructosamine, and glycosylated hemoglobin A1c (HbA1c) levels were determined before and during long-term (6 months) therapy with terazosin. A 75-g oral glucose tolerance test was performed before and during long-term terazosin therapy. Significant falls in both systolic and diastolic blood pressure in both patient groups were maintained during the long-term therapy with terazosin. Neither fasting nor postglucose-load venous plasma glucose levels were altered in either group of patients, and diabetes mellitus did not develop in any patient with NGT during the study. There was no significant change in the insulinogenic index (delta IRI/delta BS at 30 minutes after glucose load) in either patient group. In patients with IGT, glucose intolerance was slightly improved with significant reductions in HbA1c and fructosamine during terazosin therapy. Serum total cholesterol (TC) and triglyceride levels were significantly decreased in patients with IGT. In addition, TC and low density lipoprotein (LDL) cholesterol were significantly decreased in patients with hypercholesterolemia (TC > 220 mg/dL). These results suggest that long-term therapy with terazosin may improve glucose and lipid metabolism in hypertensive patients and terazosin seems to be an antihypertensive agent with beneficial effects for hypertensive patients with either dyslipidemia or impaired glucose metabolism.

Adrenergic alpha-Antagonists↗
PubMed1994

[Reoperations for valvular heart disease through repeated median sternotomy incision].

One thousand and three hundred patients underwent open heart surgery for acquired valvular diseases in our hospital from 1952 through December 1993. There were 105 reoperative cases through repeated median sternotomy incision and 52 cases of prosthetic valve replacement by the same operator in the last 5 years. We studied technical procedures by these reoperative experience. There was only one case (1.9%) of hospital death in replacement cases. We believe that repeated open heart surgery for acquired valvular diseases should be done prior to deterioration of patient's clinical condition. We had to pay attention to facilitate mobilization of right atrium and aortic root in the aortic and mitral valvular reoperations. To decrease operative mortality of prosthetic valve replacement, each operative techniques were necessary by the reasons for reoperation.

Adolescent↗
PubMed1994

[Efficacy of benzimidazole-type drugs on alveolar echinococcosis (AE)].

AE patients can be cured only by complete excision of the lesions. In Europe and the United States, however, benzimidazole-type drugs have been reported to be effective. We treated 37 patients (20 males and 17 females, mean age of 45.9 years) with mebendazole (MBZ) (n = 17) or albendazole (ABZ) (n = 20) according to the WHO chemotherapy protocol, and compared adverse reactions, drug concentrations, serological parameters, and measurable lesions by CT scan and/or X-ray examination. In the MBZ group, serological parameters were unaffected. One patient each had hepatic disorder and alopecia (12%), and 5 lesions in the liver and 3 in the lung gradually increased in size (105% in 1 year, 112% in 2 years), and showed NC (no response) in 6, PD (progressive disease) in 2. One case of released biliary obstruction were judged as PR (partial response) (Response rate: 11.1%). In the ABZ group, no adverse reactions were found and ELISA level decreased significantly in 10 out of 12 patients. One lesion in the liver, 3 in the lung, 1 in the chest wall and 1 in the retropancreatic region reduced in size significantly (Mean: 56%) (PR 3, NC 3; Response rate: 50.0%). ABZ was safer and more effective than MBZ.

Adult↗
PubMed1994

[Treatment of acute lymphoblastic leukemia in adults by the modified protocol of L-10M (Sloan-Kettering): long-term outcome].

From January 1984 to April 1988, we treated 20 patients with adult lymphoblastic leukemia (ALL) and 2 patients with lymphoblastic lymphoma with a protocol which we modified L-10M of Sloan-Kettering Cancer Center. Since the median follow up time is now over 5 years, we report the most recent outcome. Thirteen patients were male and 9 were female. The median age was 31, ranging from 15 to 71 years of age, and there were no Ph1 positive patients. The complete remission (CR) rate was 81.8%. Median CR duration was 32 months and the 5-year continuous CR rate was 33.3%. No significant prognostic factor for CR rate was found. Age at achievement CR and duration were significant prognostic factors. The 5-year continuous CR rate of patients below 35 years old was 54.5%. In this group the leukocyte count was a significant prognostic factor. All patients with a leukocyte count above 1 x 10(4)/microliters relapsed. However, in patients with a WBC below 1 x 10(4)/microliters, the 5-year continuous CR rate was 75%. Based on these results, it seems reasonable to treat patients with ALL by different therapeutic strategies according to the risk factors.

Adolescent↗
PubMed1993

Regulation of cardiac sarcolemmal Ca2+ channels and Ca2+ transporters by thyroid hormone.

In order to examine the regulatory role of thyroid hormone on sarcolemmal Ca(2+)-channels, Na(+)-Ca2+ exchange and Ca(2+)-pump as well as heart function, the effects of hypothyroidism and hyperthyroidism on rat heart performance and sarcolemmal Ca(2+)-handling were studied. Hyperthyroid rats showed higher values for heart rate (HR), maximal rates of ventricular pressure development +(dP/dt)max and pressure fall -(dP/dt)max, but shorter time to peak ventricular pressure (TPVP) and contraction time (CT) when compared with euthyroid rats. The left ventricular systolic pressure (LVSP) and left ventricular end-diastolic pressure (LVEDP), as well as aortic systolic and diastolic pressures (ASP and ADP, respectively) were not significantly altered. Hypothyroid rats exhibited decreased values of LVSP, HR, ASP, ADP, +(dP/dt)max and -(dP/dt)max but higher CT when compared with euthyroid rats; the values of LVEDP and TPVP were not changed. Studies with isolated-perfused hearts showed that while hypothyroidism did not modulate the inotropic response to extracellular Ca2+ and Ca2+ channel blocker verapamil, hyperthyroidism increased sensitivity to Ca2+ and decreased sensitivity to verapamil in comparison to euthyroid hearts. Studies of [3H]-nitrendipine binding with purified cardiac sarcolemmal membrane revealed decreased number of high affinity binding sites (Bmax) without any change in the dissociation constant for receptor-ligand complex (Kd) in the hyperthyroid group when compared with euthyroid sarcolemma; hypothyroidism had no effect on these parameters. The activities of sarcolemmal Ca(2+)-stimulated ATPase, ATP-dependent Ca2+ uptake and ouabain-sensitive Na(+)-K+ ATPase were decreased whereas the Mg(2+)-ATPase activity was increased in hypothyroid hearts. On the other hand, sarcolemmal membranes from hyperthyroid samples exhibited increased ouabain-sensitive Na(+)-K+ ATPase activity, whereas Ca(2+)-stimulated ATPase, ATP-dependent Ca2+ uptake, and Mg(2+)-ATPase activities were unchanged. The Vmax and Ka for Ca2+ of cardiac sarcolemmal Na(+)-Ca2+ exchange were not altered in both hyperthyroid and hypothyroid states. These results indicate that the status of sarcolemmal Ca(2+)-transport processes is regulated by thyroid hormones and the modification of Ca(2+)-fluxes across the sarcolemmal membrane may play a crucial role in the development of thyroid state-dependent contractile changes in the heart.

Animals↗
PubMed1993

Possible involvement of oxygen-derived free radicals in abnormal hemostasis induced by SART stress (repeated cold stress) in laboratory animals.

Abnormal hemostatic profiles indicating hemorrhagic tendency have been reported in rodents exposed to prolonged fluctuation in ambient temperature, known as SART (specific alternation of rhythm in temperature)-stressed animals. In this study, investigation was made of possible involvement of oxygen-derived free radicals in the development of stress-induced hemostatic alteration. SART-stressed rats and mice exhibited marked decrease in platelet count, fibrinogen level and factor VIII:C activity. Superoxide dismutase, when administered s.c. twice a day to mice for 7 days of stress exposure, inhibited the above alterations. Catalase given in the same manner, had essentially the same effect, though to a lesser extent. Allopurinol administered orally once daily during stress reduced stress-induced thrombocytopenia, but caused considerable increase in fibrinogen and factor VIII:C activity in stressed and unstressed mice. Lipid peroxide significantly increased in the heart but not in the plasma following stress exposure in rats and mice. Active oxygens would thus appear to be, at least partially, involved in the development of abnormal hemostasis induced by SART stress.

Animals↗
PubMed1993

Studies on the synthesis of nucleotidyl-peptides. II. The preparation of a nucleotidyl-peptide having a 5'-nucleotidyl-(P-O)-serine phosphodiester bond.

The preparation of a nucleotidyl-peptide having a thymidine-5'-yl-(P-O)-serine phosphodiester bond, [H-Ala-Ser(pTpT)-Phe-OH](24) is described. After condensation between the phosphorylated peptide component and an oligonucleotide component, all protecting groups could be removed under neutral conditions without beta-elimination of the pTpT from the serine moiety.

Nucleotides↗
PubMed1993

Effect of angiotensin converting enzyme inhibitor on regression in cardiac hypertrophy.

Cardiac hypertrophy in rats was produced by aortic banding for 6 weeks and regression of hypertrophy in these experimental animals was induced by administration of angiotensin converting enzyme inhibitor, enalapril (10 mg/kg/day) for 6 weeks. The left ventricular muscle mass and systolic pressure were decrease upon treating the hypertrophied rats with enalapril. This drug also decreased the number of alpha 1-adrenoceptors in hypertrophied myocardium without any changes in beta-adrenoceptors. The regression of cardiac hypertrophy in spontaneously hypertensive rats by enalapril for 10 weeks was not associated with any alterations in alpha 1-adrenoceptors in hypertrophied myocardium, but was decreased in beta-adrenoceptors. Effects of enalapril on extracellular matrix in the myocardium was also observed in regression of hypertrophy in which the type III collagen mRNA expression and collagen contents were reduced in comparison with those of hypertrophied myocardium. These results indicate that regression of cardiac hypertrophy is not always associated with a decrease in the number of alpha 1-adrenergic receptors and that the beneficial effects of enalapril in the hypertrophied heart in aortic banding animals may be of some specific nature.

Animals↗
PubMed1993

Characterization of platelet hypofunctions in rats under SART stress (repeated cold stress).

Platelet hypoaggregability has been reported in rats exposed to a chronic form of environmental stress induced by long-lasting fluctuation in air temperature, known as SART (specific alternation of rhythm in temperature) stress. This study examines functional characteristics of platelets from stressed rats in more detail. Exposure to stress reduced aggregation and ATP release in platelets stimulated with collagen, as determined using platelet-rich plasma (PRP). The resting levels of ATP but not ADP in platelets from stressed rats were lower than those from unstressed ones. Collagen-induced release and resting level of serotonin also decreased in platelets from stressed rats. In contrast, stress failed to cause hypoaggregability of washed platelets. Circulating platelet aggregates were detected in stressed rats. From these data, SART stress appears to cause intravascular activation of platelets in spite of in vitro hypofunctions. Alteration in plasma milieu may be associated with stress-induced platelet hypofunctions in PRP.

Adenosine Diphosphate↗
PubMed1993

Evaluation of triplet growth status at birth using individualized growth assessment: comparison with conventional methods and development of a new classification system.

A new growth classification system for triplets based on individual growth curve standards provides new information on the growth status of triplets at birth. OBJECTIVES. The objectives of this study were to characterize growth outcome at birth in triplet pregnancies using Individualized Growth Assessment methods, and to compare these results to conventional methods of growth outcome evaluation. STUDY DESIGN. Rossavik growth models derived from second-trimester ultrasound measurements were used to predict the birth characteristics of 21 triplet neonates. Actual measurements of weight, head, abdominal, and thigh circumferences at birth were compared to population standards and to predicted values, the latter by calculation of Growth Potential Realization Index (GPRI) values. GPRI values were calculated using singleton (measurement procedure correction) and triplet (measurement procedure correction+decreased soft tissue deposition) correction factors (SCF, TCF). Neonatal Growth Assessment Scores (NGAS) were calculated using both sets of GPRI values. RESULTS. Three types of triplet neonates were identified. Group I (33.3%) were normal with both types of NGAS values, had very few abnormal GPRI values or anatomic measurements, and were all appropriate for gestational age. Group III (14.3%) were abnormal with both types of NGAS values, most GPRI values were abnormal, and all were small for gestational age. Group II (52.4%) had abnormal NGAS values when calculated from GPRI values determined with SCF and normal NGAS values when calculated from GPRI values determined with TCF. All but one was AGA. Almost all GPRIWT and GPRIThC values were abnormal using SCF and normal using TCF. CONCLUSION. Although growth outcome in triplet neonates can be normal (Group I) or intrauterine growth retarded (Group III), the majority are in an intermediate group (Group II) characterized by a decrease in soft tissue mass, which may or may not be pathological.

Adult↗
PubMed1993

Quantitative characterization of arcuate artery hemodynamic change in normal pregnancy with Doppler ultrasonography.

Using color and pulsed Doppler ultrasonography, arcuate arterial velocimetry was carried out in 91 normal women, at 16-40 weeks, menstrual age. The arcuate arterial hemodynamics was assessed by the calculation of the resistance index (RI). A curvilinear relationship was found between the RI value of the arcuate artery obtained from the placental site in the uterus and menstrual age (R2 = 0.328). The relationships between the RI value of the arcuate artery obtained from the nonplacental site (R2 = 0.268) or the averaged RI value between the placental and nonplacental sites (R2 = 0.321) and menstrual age were both linear. Normal ranges of RI values of arcuate arteries during pregnancy for the placental site, nonplacental site, and their average values were generated. These results provide a foundation for evaluating uteroplacental velocimetry in normal pregnancy using Doppler ultrasonography.

Arteries↗
PubMed1993

Effect of metoprolol on the beta-adrenoceptor density of lymphocytes in patients with dilated cardiomyopathy.

We investigated the effect of the beta 1-selective blocker metoprolol on the beta-adrenergic receptor density of circulating lymphocytes in patients with dilated cardiomyopathy. Nine men in New York Heart Association functional classes II (six patients) and III were given metoprolol for 6 months (mean dose 45.6 +/- 18.1 mg). Their cardiac function was assessed by echocardiography. Although there was no difference in the heart rate or pressure rate products, the end-systolic and end-diastolic dimensions significantly decreased in six patients after metoprolol treatment. The ejection fraction, fractional shortening, and mean left ventricular circumferential shortening were significantly increased after the treatment. beta-Adrenoceptor densities of lymphocytes, examined by iodine 125-labeled iodocyanopindolol, were reduced in patients at entry but recovered to normal levels after the metoprolol treatment. The dissociation constants did not differ at any stage of the disease. The relationship between beta-adrenoceptor densities in lymphocytes and echocardiographic parameters showed a positive correlation with the plasma norepinephrine concentration. This study thus provides evidence that long-term metoprolol therapy for dilated cardiomyopathy is associated with beta-receptor up-regulation, and the restoration of myocardial beta-receptor density may be associated with the improved cardiac function as determined by echocardiography.

Adult↗
PubMed1993

Oral absorption of FK506 in rats.

The oral absorption of FK506 in solid dispersion formulation was studied in rats. The obtained area under the concentration versus time curve (AUC) increased in a nonlinear fashion with a small dose-dependent increase in the peak blood concentrations (Cmax). The peak concentration time (Tmax) was observed within 30 min after administration in all dosing groups (1-10 mg/kg) with or without feeding, whereas the oral absorption of FK506 was reduced to about 50% by gavage at a dose of 1 mg/kg. Participation of first-pass elimination was suggested by comparing the blood levels after infusion via the portal vein with those after infusion via the femoral vein. Further, in an in vitro stability study and an in situ loop absorption study, FK506 was fairly stable in the gastrointestinal juice and was absorbed predominantly from the upper part of the small intestine.

Administration, Oral↗
PubMed1993

Mathematical modeling of fetal organ growth using the Rossavik growth model: II. Adrenal gland.

Growth of the fetal adrenal gland has been monitored by measurements of the circumference (AGC) and area (AGA) of the adrenal gland from 16 to 40 weeks menstrual age. Growth curves for these parameters have been determined using a Rossavik growth curve models [P = c(t)k + s(t)]. R2 values of 86.2 and 91.1% were obtained for AGC and AGA, respectively. Variability analysis indicated a progressive increase in variability with menstrual age for these two parameters. Variability data were used with the growth curve models to determine standard curves for AGC and AGA. These standard curves provide a superior means for evaluating the adrenal growth in the fetus and the fetal status in utero in high-risk pregnancies.

Adrenal Glands↗