Biomedical subjects

K Katayama

Publications and source records attributed to K Katayama.

At least 379 records · Page 21Linked to original sources

PubMed1989

Analysis of digital subtraction coronary angiography for estimation of flow reserve in critical coronary stenosis.

To examine the accuracy of digital subtraction angiographic assessment of coronary flow reserve in critical coronary stenosis, time-density curves were obtained from digital angiograms for a myocardial region of interest. Time-to-peak contrast (TPC) and contrast washout rate (T) were measured in 11 patients with critical 1-vessel lesions before and after percutaneous transluminal coronary angioplasty (PTCA). Collectively, the values of TPC and T were significantly shortened, from 5.8 +/- 1.1 to 4.4 +/- 1.0 seconds (p less than 0.01) and from 11.3 +/- 4.0 to 5.2 +/- 1.2 seconds (p less than 0.001) after PTCA, respectively. All 11 patients except 1 showed shortened T after PTCA; however, in 5 of the 11 patients, TPC after PTCA had approximately the same values as those before PTCA. In experiments in dogs with critical circumflex stenosis, coronary flow and posterior wall thickening at rest were not different from control; however, contrast media-induced hyperemia was markedly attenuated, accompanied by a significant prolongation of T (7.7 +/- 4.5 vs 15.8 +/- 1.9 seconds, p less than 0.01) and completely unchanged TPC (both 6.8 seconds). With simultaneous tracings of coronary flow and time-density curves, TPC and the washout phase on the curve corresponded with contrast-induced transient flow reduction and hyperemic phases, respectively. It is concluded that T appears more sensitive than TPC when basal coronary flow is maintained to almost normal levels, as in patients with stable effort angina pectoris having critical coronary stenosis.

Aged↗

PubMed1989

Usefulness of negative dP/dt upstroke pattern for assessment of left ventricular relaxation in coronary artery disease.

It has been reported that regional asynchrony due to acute ischemia disturbs the exponential nature of left ventricular (LV) pressure reduction and may alter the pattern of (-)dP/dt upstroke curve. If LV pressure decreases exponentially during the isovolumic relaxation period (P = Ae-t/T + B, where A and B = constants, t = time and T = time constant), the (-)dP/dt upstroke curve should also be exponential and upward-convex because dP/dt = A(-t/T)e-t/T. To test this theory in humans, the LV (-)dP/dt upstroke curve was analyzed in 9 normal subjects, 12 patients with effort angina pectoris (AP) and 15 with old myocardial infarction (MI) under the basal conditions. The (-)dP/dt upstroke was convex-upward in all normal subjects, but convex-downward in 9 of 12 patients with AP and in all patients with MI, which suggests nonexponential decrease in LV pressure in the groups with AP and MI. The dP/dt (20/60), which is the ratio of the (-)dP/dt value at 20 ms after peak (-)dP/dt to that at 60 ms after peak (-)dP/dt, was significantly lower in the group with AP (1.70 +/- 0.07) and in the group with MI (1.61 +/- 0.13) than in normal subjects (2.08 +/- 0.18) (p less than 0.005). This indicates that (-)dP/dt upstroke 20 to 60 ms after peak (-)dP/dt increases more slowly in the groups with AP and MI than in normal subjects. Theoretical consideration showed that such a slower increase of the upstroke resulted from impaired early to midrelaxation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Left atrial conduit function for left ventricular filling dynamics in patient with myocardial infarction.

This study observed the left function in determining filling dynamics of the left ventricle in patients with myocardial infarction. The study consisted of eight control subjects and ten patients with myocardial infarction. The left ventricular filling volume is considered to be composed of the left atrial passive emptying, active emptying, and conduit volumes. The change of left ventricular filling volume was correlated with that of conduit volume (r = .87, P less than .01). However, the change of left ventricular filling volume did not have any correlation to those of left atrial passive emptying and active emptying volumes. These results suggested that the left atrial conduit function was important in determining filling dynamics of the left ventricle.

Adult↗

PubMed1989

Inhibitory effects of E-5110 on interleukin-1 generation from human monocytes.

Effects of E-5110, a novel non-steroidal antiinflammatory drug, on interleukin-1 (IL-1) generation from human monocytes were studied in vitro. E-5110 reduced the amounts of extra- and intracellular IL-1 activity induced by lipopolysaccharide (LPS, 1 micrograms/ml) in a dose-dependent manner (1-10 microM). E-5110 also inhibited the IL-1 generation induced by antigen-antibody complexes, opsonized zymosan and silica particles. It was suggested that the inhibition of IL-1 generation by E-5110 was independent of the inhibitory effects on arachidonate cyclooxygenase and/or lipoxygenase because indomethacin, piroxicam, BW755C and AA861 had no effects on IL-1 generation. Hydrocortisone (IC50:0.084 microM), aurothioglucose (11.5 microM) and lobenzarit (75.0 microM), which are clinically effective antirheumatic drugs, also inhibited IL-1 generation, like E-5110 (1.21 microM). It is expected that E-5110 will be superior to classical non-steroidal antiinflammatory drugs in medical treatment of rheumatoid arthritis.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed1989

Interleukin-1-like activity in the exudate of air-pouch inflammation in rats, and its participation in granuloma formation.

The in vivo production of lymphocyte activating factor (LAF) activity was investigated in the exudate of the rat air-pouch inflammation model. An inflammatory reaction was induced by lipopolysaccharide (LPS) injection into the air-pouch, and the time course of LAF activity in the exudate was investigated. LAF activity in the exudate reached a peak by 6 h, and rapidly decreased at 10 to 48 h after the LPS injection. Dexamethasone revealed strong inhibitory action on LAF activity and granuloma formation. On the other hand, indomethacin could not inhibit either of the phenomena. In conclusion, LAF (IL-1) is rapidly produced after the onset of inflammation and may participate in the subsequent granuloma formation.

Animals↗

PubMed1989

Interleukin 3 enhanced interleukin 2-dependent maturation of NK progenitor cells in bone marrow from mice with severe combined immunodeficiency.

Human recombinant interleukin 2 (IL 2) and highly purified murine interleukin 3 (IL 3) were tested for their ability to generate NK activity in bone marrow cells from mice with severe combined immunodeficiency. IL 2 alone could dose dependently induce NK activity in marrow cells as determined by cytotoxicity against YAC-1 target cells. It was demonstrated that IL 3 had dual effects on the generation of NK activity in this culture system. The addition of IL 3 resulted in inhibition of NK cell activity seen at high concentrations of IL 2. In contrast, when IL 3 was added together with low concentrations of IL 2, the generation of NK cells as judged by cytotoxicity assay as well as the appearance of cells with NK phenotypes was markedly augmented. In some experiments, mice were treated with 5-fluorouracil (5-FU) to eliminate relatively differentiated NK precursors from bone marrow cells. It was noted that the residual immature marrow cells from 5-FU-treated mice showed little NK activity even after the culture with high concentrations of IL 2. Importantly, IL 3 could induce the generation of NK activity from 5-FU-treated marrow cells in the presence of IL 2. Kinetic studies indicated that NK activity was appreciably generated from 5-FU-treated marrow cells when preincubated with IL 3 at least for 12 hr and subsequently cultured with IL 2. The cells bearing IL 2 receptors appeared in 5-FU-treated marrow cells, even though cultured only with IL 3, which implied that IL 3 could support the development of very primitive NK cells from IL 2-unresponsive to IL 2-responsive states. These results suggested that IL 3 might play a crucial role for the IL 2-induced generation of NK cells in bone marrow through promoting the expression of IL 2R on NK progenitor cells.

Animals↗

PubMed1989

Detection of hepatitis B virus X gene protein and antibody in type B chronic liver disease.

The genome of the hepatitis B virus contains a sequence (X gene) whose role is unclear. The almost complete region of the hepatitis B virus X gene was expressed in Escherichia coli, with the resulting protein being approximately 17 kilodaltons in molecular weight. Sera from 139 subjects were analyzed by Western blot analysis. Of the hepatitis B surface antigen-positive patients, anti-X was not found in 4 patients with acute hepatitis and in 12 healthy carriers, but was present in 41% (21/51) of the patients with chronic hepatitis, 63% (15/24) of those with liver cirrhosis, and 46% (12/26) of those with hepatocellular carcinoma. The expression of the X product in the liver tissues (43 hepatitis B surface antigen-positive patients) was investigated using an indirect immunohistochemical method. The X protein was observed in 64% (21/33) of the patients with chronic hepatitis and 50% (5/10) of those with liver cirrhosis, and was found when the serum was negative for anti-X. Hepatitis B core antigen was frequently expressed together with the X protein in the liver. The conclusions reached were that the frequency of anti-X increases with the length of chronic hepatitis B virus infection, that anti-X may suppress the expression of the X protein in the liver, and that the X protein may be related to hepatitis B virus replication.

Blotting, Western↗

PubMed1989

Effect of diltiazem on aortic pressure-diameter relationship in dogs.

To study the effects of diltiazem (Dz) on aortic (Ao) pressure-diameter (P-D) relationships, the external diameter (D) of the thoracic Ao (sonomicrometry) and Ao pressure (AoP, micromanometer) were simultaneously measured in 10 anesthetized dogs. The P-D relationship from 80 ms after the dicrotic notch of AoP (t80) to 20 ms after the peak of the next R wave on the electrocardiogram (ECG) (t20) was plotted at 30-ms intervals. To depict the P-D relationship in a wide range of AoP, Ao occlusion immediately after the release of inferior vena caval (IVC) occlusion was performed both before and after a Dz (0.03 mg.kg-1.min-1, over 10 min) infusion. The P-D relationship so obtained was a sigmoid curve under both conditions and was reasonably described by a cubic curve (P = aD3 + bD2 + cD + d, where a, b, c, and d are constants and r greater than 0.99). The first derivative of cubic regression equation (dP/dD) value of the cubic curve was used as an index of Ao stiffness. In all dogs, the dP/dD-D relationship, which was parabolic, was similar to the delta P/delta D-D relationship measured from the actual P-D relationship (delta P/delta D is the ratio of the change in AoP to that in AoD), suggesting that it corresponded to a cubic curve.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1989

Kinetic studies of the pharmacologic response to captopril in rats. I. Role of the renin-angiotensin system.

Pressor response to exogenous angiotensins was investigated in rats. Two-kidney Goldblatt hypertensive rats (GHR) and sodium-deficient normotensive rats (SDR), as well as normal rats, (NR) were used. Various amounts of angiotensin I (Ang I) or angiotensin (Ang II) were administered intravenously by constant infusion, with or without pretreatment with angiotensin converting enzyme (ACE) inhibitor, and the pressor response was determined. Captopril was used as the ACE inhibitor. From the data obtained, a simple kinetic model for the renin-angiotensin system was constructed. The model was based on a linear compartment model with the following assumptions; (a) there are compartments in respect to Ang I and II in the body; (b) in the steady-state condition, Ang I is produced at a constant rate; (c) a part of Ang I is converted to Ang II by a first-order rate process; (d) Ang I and II are eliminated from the respective compartments by first-order rate processes and (e) the relationship between mean arterial blood pressure and the amount of Ang II in the body can be described by Hill's equation with a baseline effect. Then the pressor response to angiotensins in GHR, SDR or NR was fitted to the model. The result indicated that the pressor response to Ang I or Ang II can be described by the present model. The model parameters obtained were consistent with the actual physiological parameters of rats.

Angiotensin I↗

PubMed1989

Kinetic studies of the pharmacologic response to captopril in rats. II. Hypotensive effect and plasma angiotensin converting enzyme activity.

The effect of captopril on the mean arterial blood pressure was studied in rats. Two different disease-state rats, namely the sodium-deficient rat (SDR) and the two-kidney-one-clip Goldblatt hypertensive rat (GHR), as well as normotensive rats (NR), were used. After i.v. bolus administration of captopril to each rat, the time course of plasma angiotensin converting enzyme (ACE) activity and mean arterial blood pressure were determined. In a different experiment, the effect of captopril on the plasma ACE activity in vitro was determined. Captopril inhibited the plasma ACE activity in a concentration-dependent manner and the relationship between concentration of captopril and inhibition of plasma ACE activity in vitro was reasonably described by a Langmuir-type equation. Then, plasma concentrations of captopril after i.v. administration were estimated by means of this equation. The estimated plasma concentration of captopril followed a double exponential equation. From the data obtained, a kinetic model including the renin-angiotensin system and pharmacokinetics of captopril was constructed under the following assumptions; (1) the hypotensive effect of captopril is solely attributable to the reduction of angiotensin II level in the body, (2) the production rate of angiotensin II is proportional to the total ACE activity and (3) plasma ACE activity reflects the total ACE activity in the body. Then, the effect of captopril on the mean arterial blood pressure in each type of rat was calculated. The results indicated that the hypotensive effect of captopril in NR was reasonably described by the model. However, the hypotensive effect of captopril in both GHR and SDR could not be well described by the model.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1989

Factors affecting sulfisoxazole transport through excised rat skin during iontophoresis.

Permeation of sulfisoxazole (SIX) across the excised rat skin were studied using two chamber cell with four electrodes, under three successive experimental conditions: without current for 3 h (treatment I), with current for 4 h (treatment II) and without current for 3 h (treatment III). Transport of SIX was significantly increased by iontophoresis. The enhancement ratio of SIX flux were reasonably predicted by Goldman's equation. There was no significant difference (p less than 0.05) between the flux in treatment I and treatment III. On the basis of the flux reversibility, it was concluded that skin alteration did not occur when the applied electric potential was below 5.025 V. Although a prominent current-induced volume flow (from the anodal side to the cathodal side) was observed during current exposure, SIX flux was not influenced by the volume flow. The flux enhancement of SIX was mainly dependent on transdermal potential difference.

Animals↗

PubMed1989

[Enhanced percutaneous absorption of formoterol furmarate via pulsed iontophoresis. I. Effect of constant current and constant voltage].

The effect of iontophoresis on percutaneous absorption of formoterol fumarate (FF) was investigated in vitro with abdominal skin excised from guinea pig. By passive diffusion, the flux at steady state for stripped skin was about 230 times greater than that for intact skin. Therefore, it is suggested that stratum corneum is a barrier for the percutaneous absorption of FF. Penetrated amount of FF increased significantly with an increase in donor concentration from 0.035% to 0.07%. Under the constant current iontophoresis the large flux accompanied with the high applied voltage was shown at the beginning of iontophoresis. Thereafter the flux decreased with a decrease in applied voltage. Under the constant voltage iontophoresis a linear relationship between penetrated amount of FF and time was observed.

Animals↗

PubMed1989

[Enhanced percutaneous absorption of formoterol fumarate via pulsed iontophoresis. II. Effect of polarity, pulse frequency and duty].

To clarify the effect of polarity, pulse frequency and duty on the iontophoretic transport of formoterol fumarate (FF), in vitro and in vivo studies were performed with guinea pigs. In the in vitro studies, the flux at steady state was enhanced by the factor 7.61 with anodal iontophoresis in comparison with control, whereas, with cathodal iontophoresis it was restrained by the factor 0.79. When pulse frequency was varied from 0 to 40 kHz, the flux at steady state was enhanced with an increase in pulse frequency. In the in vivo studies with varying the duty of pulse potential from 10 to 100%, the maximum plasma concentration of FF was obtained at a 30% duty. In contrast, the plasma concentration of FF achieved at 100% duty was not high. With stripped skin, no significant difference in the plasma concentration of FF was shown between iontophoresis and control. Consequently, it is suggested that iontophoresis contributes to FF penetration across stratum corneum.

Animals↗

PubMed1989

The effect of left ventricular wall motion during isovolumetric relaxation period in coronary artery disease.

The effect of the left ventricular (LV) regional wall motion during isovolumetric relaxation period (IRP) were studied in 9 patients with old anteroseptal myocardial infarction (OMI) and 8 normal subjects (NOR). There were no significant differences in heart rate, peak LV systolic pressure and peak (+) dP/dt between the groups. LV cavity was divided into the anterior and inferior sides by a long axis, which was equally divided with 3 perpendicular lines, creating 4 areas in each side. The sums of the 2 middle areas in each side were defined as Aa and Ab, respectively. During IRP the pattern of (-) dP/dt at the upstroke phase was convex-downward in OMI, but convex-upward in NOR. Time constant (T) was significantly prolonged in OMI compared with NOR (50 +/- 9 vs 37 +/- 6 msec; p less than 0.01). On NOR, Aa increased significantly after 33.4 msec from peak (-) dP/dt, while Ab remained unchanged. In OMI, Ab increased after 50.1 msec from peak (-) dP/dt, associated with decrease in Aa, suggesting the passive shortening of the anterior wall by the active expansion of the inferior. Such asynchronous LV wall motions during IRP might impair LV relaxation and influence the upstroke pattern of (-) dP/dt.

Adult↗

PubMed1989

Preparation of 3-amino-3-deoxy derivatives of trehalose and sucrose and their activities.

The 3-keto derivatives of trehalose and sucrose respectively were prepared by a one-step enzymatic route using D-glucoside 3-dehydrogenase from Flavobacterium saccharophilum. Reductive amination of 3-ketotrehalose with ammonium acetate and sodium cyanoborohydride gave three compounds, 3-amino-3-deoxy-alpha-D-allopyranosyl alpha-D-glucopyranoside, 3-amino-3-deoxy-alpha-D-glucopyranosyl alpha-D-glucopyranoside (3-trehalosamine) and 3-amino-3-deoxy-alpha-D-mannopyranosyl alpha-D-glucopyranoside. From the reductive amination of 3-ketosucrose, 3-amino-3-deoxy-alpha-D-allopyranosyl beta-D-fructofuranoside and 3-amino-3-deoxy-alpha-D-glucopyranosyl beta-D-fructofuranoside were obtained. The antibiotic and glycohydrolase inhibitory activities of these 3-amino-3-deoxy derivatives were determined.

Amination↗

PubMed1989

Determination of alpha 2-macroglobulin-trypsin complex with a new synthetic substrate.

We have developed a colorimetric assay for quantifying alpha 2-macroglobulin-trypsin complex (alpha 2M-TRY) in human serum, based on use of a new chromogenic substrate D-gamma-tert-butyloxy-Glu-Gly-Arg-3-carboxy-4-hydroxyanilide dihydrochloride (PS-3001). Within-run CVs by this assay were 4.76%, 1.57%, and 0.83% for trypsin complex concentrations of 3.1, 12.2, and 48.1 U/L, respectively (n = 10 each). Between-day CVs were 5.38%, 3.12%, and 2.20% at each concentration, respectively (n = 7). Mean analytical recoveries of alpha 2M-TRY added to serum were 100%, 105%, and 101% for 9.2, 15.1, and 46.3 U/L, respectively (n = 2). The standard curve obtained was linear up to 330 U/L. We applied this method to the study of alpha 2M-TRY activity in sera from 97 healthy subjects (group 1), from 27 patients with acute pancreatitis (group 2), and from 25 patients with other chylopoietic diseases (group 3); results ranged from 0 to 1.2 U/L (mean = 0.5, SD = 0.3), from 1.2 to 77.4 U/L (mean = 14.6, SD = 19.0), and from 0 to 1.3 U/L (mean = 0.4, SD = 0.3), respectively. Concentrations of enzymatically active alpha 2M-TRY were significantly greater in sera from group 2 than in groups 1 and 3. The determination of serum alpha 2M-TRY activity by this simple, rapid, colorimetric method may be useful for the diagnosis and evaluation of pancreatic disease.

Acute Disease↗

PubMed1989

[Effect of PMU hepatic arterial chemotherapy for liver metastases of gastric cancer. Hokuriku Cisplatin Round-table Conference].

We performed PMU hepatic arterial chemotherapy (a combination therapy consisting of intra-hepatic arterial infusion of CDDP and MMC, oral administration of UFT) in 20 patients with gastric cancer and liver metastases. In this method, 1-6 courses of one infusion of CDDP at 70-100 mg/body and MMC of 10 mg/body into the proper hepatic artery were administered at intervals of 3-4 weeks. UFT of 300-400 mg/day was orally administered with the infusion. The primary response for hepatic metastatic lesions was observed in one case of CR, 14 cases of PR, 4 cases of NC, and one case of PD. The efficacy for CR and PR was high at 75%. The median disease-free interval was 56 weeks in responders. The 50% survival period was 11.1 months; one-year survival rate, 42.1%; two-year survival rate, 12.3%; the longest survival period was 108 weeks. Mild and transient side effects were recognized in 17 cases (85%): gastrointestinal symptoms, sense of general malaise, fever, leukocytopenia, and elevated BUN. Thus, the results indicated that this combination chemotherapy was effective for liver metastases of gastric cancer.

Administration, Oral↗

PubMed1989

[Expression of Pre-S2 antigen and antibody in patients with hepatitis B virus infection].

We investigated the expression of Pre-S2 antigen (Ag) and antibody (Ab) in sera quantitatively using ELISA. Four patients with acute hepatitis B and 87 chronic HBV carriers were included in this study. We also investigated the expression of Pre-S2Ag in the liver tissues obtained from 26 chronic HBV carriers by direct fluorescent antibody method. There was a significant correlation between Pre-S2Ag titers and HBsAg titers in sera. Pre-S2Ag titers were higher in sera positive for HBeAg, HBV-related DNA polymerase or HBV-DNA than in sera negative for those markers. The ratio of Pre-S2Ag titers to HBsAg titers, however, was constant irrespective of virus replicative markers. Pre-S2Ag in the liver had almost same intracellular localization with HBsAg in the liver. It was suggested that Pre-S2Ag was expressed with an intimate relation to the expression of HBsAg and was not useful as a virus replicative marker. Pre-S2Ag titers/HBsAg titers tended to be high in patients with chronic active hepatitis and high serum GPT levels compared to patients with chronic inactive hepatitis. This may be explained by the release of Pre-S2Ag in the liver. In addition, all patients positive for Pre-S2Ag on the membrane of hepatocytes had chronic active hepatitis. The overproduction of Pre-S2-containing surface proteins in the liver may have some implication related to cell injury via the immune response to Pre-S2Ag etc. Pre-S2Ab was detected only in few cases of chronic HBV infected patients. The lack of immune response to Pre-S2 region may play a role in the persistence of HBV infection.

Enzyme-Linked Immunosorbent Assay↗