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Biomedical subjects

A Shibata

Publications and source records attributed to A Shibata.

At least 379 records · Page 21Linked to original sources
PubMed1990

[Abnormal local ventricular electrogram and its relation to induction of ventricular tachycardia in patients with hypertrophic cardiomyopathy].

To investigate the mechanism of induction of ventricular tachycardia (VT) in patients with hypertrophic cardiomyopathy (HCM), we reviewed and analyzed the local ventricular electrograms (LVE) at the pacing sites in 15 patients with HCM and 52 control subjects. Each patient had a clinical history of nonsustained VT or syncope. The results were as follows: 1. Rapid and polymorphic VT was induced in six of the 15 patients with HCM and in 10 of the 52 control subjects. 2. The duration of the LVE at the pacing site was progressively prolonged as the number of extrastimuli were increased or the premature intervals were shortened. Compared with the controls, patients with HCM had longer durations of the LVE by basic drive, single extrastimulus, and by double extrastimuli: 113 +/- 31 vs 95 +/- 16 ms (p less than 0.005), 156 +/- 35 vs 109 +/- 17 ms (p less than 0.001), and 220 +/- 88 vs 133 +/- 25 ms (p less than 0.001), respectively. 3. In the HCM group, the maximum duration of the LVE by double ventricular extrastimuli was significantly longer in patients with inducible VT compared with those with non-inducible VT: 287 +/- 95 vs 183 +/- 56 ms (p less than 0.05). 4. Induction of VT in the HCM group was accompanied by the critical prolongation of the LVE at the pacing site. In two of the six patients with HCM, the LVE at the pacing site spanned the entire cardiac cycle at the time of the initiation of VT.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiomyopathy, Hypertrophic↗
PubMed1990

The role of cigarette smoking and drinking in the development of liver cancer: 28 years of observations on male cohort members in a farming and fishing area.

Cohort studies of 639 males in a farming area (Cohort I) and 677 males in a fishing area (Cohort II) in Kyushu, Japan, had been conducted to assess the involvement of smoking and drinking in the development of liver cancer. An observed-to-expected (O/E) ratio of liver cancer was 1.3 in Cohort I and 3.1 (p less than 0.01) in Cohort II. A significant excess in deaths was found in Cohort II. No significant risk elevation was observed for smokers and drinkers in Cohort I. Although the odds ratio (OR) of 3.6 (0.6 to 22.3) suggested an elevated risk among cigarette smokers in Cohort II, no clear linear trend of ORs was observed. In contrast, a significant elevation of OR (7.0) was noted among shochu drinkers in this cohort. The respective ORs were 5.0 (1.3 to 19.7), 8.6 (2.1 to 36.1), 14.1 (3.6 to 55.9) for shochu drinkers of less than 1, 1 to 2, and 2+ units (approximately 180 ml in volume), and a highly significant dose-response relationship was observed (chi 2 = 12.1; p less than 0.001). Multiple logistic regression analysis indicated an insignificant effect of smoking and a major contribution of drinking to the development of liver cancer. Shochu drinking (or probably high alcohol intake) seems to have a significant involvement in the etiology of liver cancer, at least in Cohort II.

Aged↗
PubMed1990

[A clinical study on S6472, sustained release preparation of cefaclor, dermatological area].

We conducted a clinical investigation on the use of S6472, an sustained release preparation of cefaclor, in the dermatological area. Thirty-two patients serving as subjects were divided into group I (14 cases, including folliculitis and acne pustulora), group II (16 cases, including furuncle, furunculosis and carbuncle) and others (2 cases). One or 2 wrappers (375 or 750 mg) of S6472 were orally administered to patients twice daily after meals. In group I, the efficacy rate was 100%. Clinical results were as follows: Excellent (6 cases), good (8 cases), fair (0), and poor (0). In group II, the efficacy rate was 93.8%: Excellent (10 cases), good (5 cases), fair (1 case), and poor (0). A decrease of the bacteriological effect was observed in 1 case with Staphylococcus epidermidis. A superinfection was noted in 1 case Staphylococcus aureus. The causative bacteria were all eradicated in the remaining 24 cases. No side effects were detected. From the above results, S6472 appears to be a useful preparation, twice daily oral administration has excellent effects against dermatological infections.

Administration, Oral↗
PubMed1990

[Low dose continuous infusion therapy with etoposide (VP-16) and cytosine arabinoside (Ara-C) for a patient with refractory acute myelogenous leukemia].

A 36-year-old man with acute myelogenous leukemia, refractory to the combination chemotherapy, developed fungal infection and acute respiratory distress. Simultaneously, rapid proliferation of leukemic cells was observed in the blood. He was given continuous drip infusion of etoposide (50 mg/day) and Ara-C (20 mg/day) for 18 days. The leukemic cells disappeared from both the blood and the marrow, and complete remission was achieved. There was no adverse effect related to this therapy. The low dose combination chemotherapy with etoposide and Ara-C is safe to be carried out, and could be effective for the patients with refractory leukemia.

Adult↗
PubMed1990

[Myelodysplastic syndrome with complex chromosome abnormalities and peculiar fibril formation in granulocytes].

We report a case of myelodysplastic syndrome with peculiar fibril formation in granulocytes shown through electron microscope and complex karyotypic abnormalities including ring chromosomes. The patient, a 76-year-old male, was consulted for mild pancytopenia in February 1987. After 5 month, his hematological findings showed severe pancytopenia getting worse rapidly and presence of blasts in the peripheral blood. He had slightly hypercellular marrow with marked trilineage dysplasia and increased number of blasts (12.6%). Chromosome analysis from the bone marrow cells revealed its various structural abnormalities, especially in No. 3, 4, 5, 7, 11 with translocation on 11q11, and large ring chromosomes derived from unknown one. By electron microscopic study, we observed bizarre structures, which was peculiar fibril formation as bundles of filament resembling actin paracrystals, throughout cytoplasm as well as within nucleus in granulocytes.

Aged↗
PubMed1990

[Effect of splenectomy for management of thrombocytopenia associated with systemic lupus erythematosus: a case report].

A 51-year-old female with systemic lupus erythematosus (SLE) was admitted in November 1987 because of general fatigue and muscular weakness. She was treated with prednisolone (PSL) 30 mg and azathioprine (AZP) 50 mg after failure in the management of thrombocytopenia by PSL 15 mg. She exhibited no splenomegaly. Muscular atrophy and weakness were seen in the proximal muscles. Her platelet count was 44,000/microliters. A bone marrow aspiration revealed an increase in megakaryocytes. The blood chemistry revealed a normal CPK level and an elevated LDH level, indicating a presence of steroid myopathy. A splenectomy was performed after an increase of platelet count by giving gamma-globulin 400 mg/kg for 5 days. The platelet count rose to 368,000/microliters on the 46th postoperative day. She was treated with PSL 5 mg and AZP 50 mg as postsplenectomy therapy. The splenectomy did not adversely affect other aspects of SLE, in particular, renal function. She had no major complications in the postoperative period. Her platelet count reached a plateau 4 months later and revealed 115,000/microliters 18 months postoperatively.

Female↗
PubMed1990

Mortality of hematopoietic disorders and hair dye use among barbers.

A total of 8,316 barbers were followed up from 1976 to 1987 to examine the relations between hair dye use and deaths from hematopoietic disorders. The follow-up rate was about 95%. Three leukemia deaths and two malignant lymphoma deaths were observed in this cohort. The observed deaths were less than the expected number calculated from age- and sex-specific mortality of the general population in Japan (3.8 and 3.0, respectively). No deaths from aplastic anemia or the other hematopoietic disorders were observed.

Adult↗
PubMed1989

Plasmin-a2-plasmin inhibitor complex in plasma of patients with thromboembolic diseases.

Plasmin generation in vivo was assessed by measuring plasma levels of plasmin-a2-plasmin inhibitor complex (PAP) with an ELISA in 42 patients with arterial or venous thromboembolic diseases. Plasma concentration of PAP was markedly elevated in patients with venous thromboembolic diseases during acute illness (3.32 +/- 3.71 ug/ml, mean +/- SD) as compared to healthy subjects (0.24 +/- 0.13 ug/ml, n = 14), while it was nearly normal (0.30 +/- 0.13 ug/ml) in patients with venous thromboembolic diseases in chronic stage. Patients with arterial thromboembolism had modestly elevated PAP; 1.05 +/- 0.77 ug/ml during acute episode, and 0.84 +/- 0.40 ug/ml in chronic stage. These results indicate that excessive activation of fibrinolytic system (plasmin generation in vivo) occurs actually in many patients with thrombotic diseases, especially in venous thromboembolic diseases during acute illness.

Acute Disease↗
PubMed1989

Plasma von Willebrand factor proteolysis in patients with chronic myeloproliferative disorders: no possibility of ex vivo degradation by calcium-dependent proteases.

Patients with chronic myeloproliferative disorders (CMPD) frequently have abnormalities of plasma von Willebrand factor (vWf) multimers. The pathogenesis of this phenomenon is still unknown. In order to evaluate the possibility of ex vivo degradation of vWf during blood processing, we compared vWf antigen, ristocetin cofactor and the multimeric composition of vWf in plasmas obtained in the presence of trisodium citrate with or without calcium-dependent protease inhibitors (leupeptin, N-ethylmaleimide and Na2EDTA). The subjects included 20 patients with CMPD, 11 with other diseases and 8 normal subjects. In patients with CMPD and normal subjects, the values of vWf antigen, ristocetin cofactor, ristocetin cofactor/vWf antigen ratio and the relative amount of large multimers of vWf did not significantly differ from each other in plasma samples with and without protease inhibitors. In other diseases, especially in a patient with disseminated intravascular coagulation, a somewhat higher amount of large multimers were found in plasma with protease inhibitors than without inhibitors. These findings indicate that the ex vivo proteolysis during blood processing is negligible in patients with CMPD, and that the observed abnormalities in vWf is an in vivo phenomenon.

Calcium↗
PubMed1989

Activation of blood coagulation and fibrinolysis in diabetes mellitus: evaluation by plasma levels of thrombin-antithrombin III complex and plasmin-alpha 2-plasmin inhibitor complex.

Diabetes mellitus (DM) is associated with an increased incidence of vascular complications. Abnormalities in the hemostatic system contribute at least in part to the development of vascular disease or atherosclerosis. In order to assess the actual degree of activation of the coagulation and fibrinolytic systems in diabetics, plasma levels of thrombin-antithrombin III complex (TAT) and plasmin-alpha 2-plasmin inhibitor complex (PAP) were measured together with tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI-1) in 18 patients with DM (three patients with type I DM and 15 with type II DM). Mean plasma levels of TAT (2.5 +/- SD 1.2 ng/mL) and PAP (0.9 +/- 1.2 micrograms/mL) were significantly elevated in diabetics as compared with healthy subjects (1.7 +/- 0.3 ng TAT and 0.2 +/- 0.1 micrograms PAP per mL of plasma; p = 0.009 and 0.02, respectively). Plasma antigen concentration of t-PA but not of PAI-1 was also elevated. No difference was found in the levels of these variables between type I and type II diabetics or between patients with and without retinopathy or nephropathy. These findings indicate that continuous activation of coagulation and fibrinolysis actually occurs in the majority of the patients with DM.

Adult↗
PubMed1989

Serum concentration of beta-carotene and intake frequency of green-yellow vegetables among healthy inhabitants of Japan.

Serum levels of beta-carotene were measured among healthy inhabitants (671 males and 948 females) of 2 towns in Japan to determine the association between the levels and intake frequency of green-yellow vegetables. Those individuals who consumed green-yellow vegetables frequently showed higher levels of serum beta-carotene than those who ate them less often. The influences of alcohol drinking, smoking, obesity and age on serum beta-carotene levels were similarly observed for the 2 areas. The factors listed above were used for adjustment, giving a significant association between intake frequency of green-yellow vegetables and serum beta-carotene level. The proportion of the subjects who rarely consumed green-yellow vegetables was larger among smokers than among non-smokers. There was a large difference in serum beta-carotene levels between the 2 towns, which could not be explained by alcohol drinking and smoking. Women showed statistically significantly higher serum beta-carotene levels than men.

Adult↗
PubMed1989

Plasma protein S in disseminated intravascular coagulation, liver disease, collagen disease, diabetes mellitus, and under oral anticoagulant therapy.

Plasma levels of protein S (PS) antigen, both total and free fractions, were measured together with C4b-binding protein (C4bp) and protein C (PC) antigen in 39 patients with disseminated intravascular coagulation (DIC), 34 with liver disease, 17 with collagen disease, 17 with diabetes mellitus, and 51 under stabilized warfarin treatment. In patients with DIC, mean concentrations of total PS and free PS were normal, while PC was reduced and C4bp were elevated. Total PS, free PS, C4bp and PC were all decreased in liver disease, elevated in diabetes mellitus, and normal in collagen disease. In warfarin-treated patients, total PS, free PS and PC were moderately decreased, but the decrease in C4bp was minimal. The concentration of PS correlated positively with PC in liver disease, diabetes mellitus, and during oral anticoagulation, but did not in DIC. These results indicate that PS and PC behave similarly when liver synthetic function is principally affected, but in contrast to PC, PS is hardly consumed during intravascular coagulation.

Administration, Oral↗
PubMed1989

[Hazard ratio estimated from a proportional hazard model including two strongly correlated prognostic factors].

Estimates of hazard ratio from hypothetical survival data were examined, under the condition that the survival is affected by two prognostic factors X1 and X2 with two discrete values (0, 1) which are strongly correlated. Survival curves from the data were assumed to fit an exponential function. As an example, following numbers of subjects were used; 100 cases with X1 = 0 and X2 = 0, 10 cases with X1 = 1 and X2 = 0, 10 cases with X1 = 0 and X2 = 1, and 100 cases with X1 = 1 and X2 = 1. When the hazard ratio of X1 = 1 or X2 = 1 to X1 = 0 and X2 = 0 was 3, univariate analysis gave reasonable estimates around 3. Under the same condition, estimates of hazard ratio from multivariate analysis including the two variables X1 and X2 varied widely, depending on the survivals of 20 cases with X1 = 1 X2 = 0 or X1 = 0 X2 = 1. Probability of having extremely deviated estimates was demonstrated. The result illustrated successfully some points we should take into account when proportional hazard models including strongly correlated variables are applied.

Actuarial Analysis↗
PubMed1989

[Explanatory essay for researchers who plan to analyse their clinical data using Cox's proportional hazard model].

Proportional hazard model was proposed by Cox as a multivariate model suitable for evaluation of prognostic factors and/or therapeutic effects. This paper aims at explaining fundamental concepts of the model for clinical researchers, as clear as possible. The relationship between hazard ratio and survival curves is demonstrated using an example of survivals calculated from an exponential function. Usage of computer programme SAS is described in brief for the readers who plan to analyse their own clinical data by this model.

Analysis of Variance↗
PubMed1989

Coagulation studies in thrombotic thrombocytopenic purpura, with special reference to von Willebrand factor and protein S.

The profile of blood coagulation and fibrinolysis was studied in detail in eight patients with acute thrombotic thrombocytopenic purpura (TTP). In the majority of the patients, fibrinogen, factor XIII, antithrombin III, alpha 2-plasmin inhibitor, plasminogen, and alpha 2-macroglobulin were normal, whereas FDP, plasmin-alpha 2-plasmin inhibitor complex, and tissue-type plasminogen activator antigen were marginally or moderately elevated. Low fibronectin values were observed in four patients. Protein C and C4b-binding protein were nearly normal, whereas total protein S and free protein S were reduced in five and six patients, respectively. A positive correlation was found between total protein S and C4 and between free protein S and C3. von Willebrand factor antigen (vWf:Ag) and ristocetin cofactor (RCof) were either normal or elevated, but RCof/vWf:Ag ratio was decreased in seven patients. Crossed immunoelectrophoresis and sodium dodecyl sulfate (SDS)-agarose gel electrophoresis revealed that the large vWf multimers were either absent from or relatively decreased in all patients except one. In addition, one patient had unusually large vWf multimers, and a low-molecular-weight vWf fragment was apparently observed in three patients. These findings indicate that the intravascular generation of thrombin and plasmin was minimal in TTP and suggest that the alterations of the vWf molecule were caused not only by consumption through its participation in platelet thrombus formation but also by accelerated proteolysis. Low protein S values would be related to the immunological abnormalities underlying TTP.

Adolescent↗