Search PubMed⌕ Search

Biomedical subjects

K Fujioka

Publications and source records attributed to K Fujioka.

At least 91 records · Page 5Linked to original sources

Augmentation of antitumor effect on syngeneic murine solid tumors by an interleukin 2 slow delivery system, the IL-2 mini-pellet.

We evaluated the antitumor effect of an interleukin 2 (IL-2) slow delivery system, the IL-2 mini-pellet, in two murine solid tumor models, and also investigated the enhancement of its therapeutic effect by serial administration. The IL-2 mini-pellet contains 1 x 10(6) units of IL-2 and releases it slowly in vivo. In our experiment, the IL-2 mini-pellet was administered subcutaneously near the tumor site in combination with the intravenous injection of lymphokine-activated killer (LAK) cells. When this regimen was given on days 8 and 11 after the subcutaneous inoculation of Meth A fibrosarcoma into BALB/c mice, tumor growth was significantly inhibited (p less than 0.05) compared to tumor growth in untreated controls. Moreover, the IL-2 mini-pellet alone was also effective in inhibiting tumor growth. In another experiment, MH134 hepatoma was inoculated into C3H/He mice. Both administration of the IL-2 mini-pellet alone and in combination with LAK cells resulted in complete tumor regression in four of five mice. In a third experiment, serial administration of the IL-2 mini-pellet at 3- or 5-day intervals prolonged the suppression of Meth A fibrosarcoma growth in BALB/c mice. These results suggested that the IL-2 mini-pellet could be applied to cancer immunotherapy and that its antitumor effect could be prolonged by serial administration.

Animals↗

Use of relative weight and Body Mass Index for the determination of adiposity.

Relative weight and Body Mass Index (BMI) are commonly used as measures of body fatness in epidemiologic and clinical studies. In order to determine their accuracy, they were compared to body fat measured by underwater weighting and total body water determination in 29 males and 75 females who varied widely in body composition. Relative weights calculated from the Metropolitan Life Insurance Tables correlated so highly with BMI that these measures can be considered to be identical (R2 = 0.992 to 0.999). Linear regression analysis showed a significant correlation between BMI and percentage body fat in men (R2 = 0.68, %fat = 0.99 X BMI -1.32, p less than 0.001) and women (R2 = 0.74, %fat = 0.94 X BMI + 10.77, p less than 0.001). We conclude that relative weight and BMI are nearly identical, and that they are reasonable estimates of body fatness.

Adipose Tissue↗

Magnetic-resonance imaging used for determining fat distribution in obesity and diabetes.

Computed-tomography scanning and magnetic-resonance imaging (MRI) have been used to quantify intraabdominal and subcutaneous fat depots. In this study MRI was used to define fat-distribution patterns in 24 obese females with non-insulin-dependent diabetes (NIDDM) and 12 females with simple obesity. Subjects had anthropometric measurements and single-slice abdominal scans performed at the umbilicus. In addition, in 10 of the nondiabetic females, measurements were repeated after 10 wk of a very-low-calorie diet. Nondiabetic females had significantly less intraabdominal fat (P less than 0.01) than did the diabetics but had equivalent subcutaneous fat. There was no significant relationship between waist-to-hip ratio and intraabdominal fat, subcutaneous fat, or their ratio. After a weight loss of 10.6 +/- 3.8 kg there were significant decreases in both intraabdominal and subcutaneous fat (P less than 0.01). Weight loss is associated with decreases in fat in both depots.

Adipose Tissue↗

Derived pulmonary capillary pressure changes after smoke inhalation in sheep.

BACKGROUND AND METHODS: We determined derived pulmonary capillary pressure and the longitudinal distribution of pulmonary vascular resistance in chronically instrumented sheep with inhalation injury by using analysis of pressure decay curves after pulmonary artery occlusion. RESULTS: There was an increase in derived pulmonary capillary pressure and an increase in the lung lymph flow after smoke inhalation. The pulmonary vascular, arterial, and venous resistances increased significantly in the inhalation group. Pulmonary venous resistance increased proportionately more than pulmonary arterial resistance in the inhalation group. The plasma osmotic pressure-derived pulmonary capillary pressure gradient decreased to a greater extent in the inhalation group than in the control group. CONCLUSIONS: The present experiments suggest that the estimates of derived pulmonary capillary pressure can predict filtration pressure better than pulmonary artery occlusion pressure. The derived pulmonary capillary pressure can be measured easily in man with a pulmonary arterial catheter.

Analysis of Variance↗

Thromboxane synthase inhibition and cardiopulmonary function during endotoxemia in sheep.

We studied the cardiopulmonary response to endotoxin (lipopolysaccharide, LPS) in sheep with and without the administration of a thromboxane synthase inhibitor, OKY-046. The animals were instrumented for crystalographic dimension analysis of the left ventricle (LV) and for measurement of LV, aortic, left atrial, and pulmonary arterial pressures and cardiac index, as well as lung lymph flow. They received 1.0 micrograms/kg of Escherichia coli LPS with (n = 8) and without (n = 8) OKY-046 (10 mg/kg bolus, then 10 micrograms.kg-1.min-1). OKY-046 prevented the increase of pulmonary arterial pressure and the decrease of cardiac index that occurred during the early phase of endotoxemia. Between 8 and 12 h after LPS, cardiac index increased from 6.8 +/- 0.7 to 8.9 +/- 0.51.min-1.m-2. Concomitantly, the end-systolic pressure-diameter relationship (ESPDR, sensitive myocardial contractility index) significantly decreased from 14.7 +/- 0.6 to 7.7 +/- 0.7. Other indexes of the LV contractility (+dP/dtmax) were also reduced. OKY-046 prevented the decreases of ESPDR and +dP/dtmax. OKY-046 also attenuated the increased lung lymph flow changes seen with LPS.

6-Ketoprostaglandin F1 alpha↗

Effects of rhubarb tannins on uremic toxins.

The effects of each of several tannins purified from Rhei Rhizoma on serum constituents were investigated in rats with adenine-induced renal failure. Blood levels of urea nitrogen, methylguanidine (MG), and guanidinosuccinic acid (GSA) were significantly decreased in rats given (-)-epicatechin 3-O-gallate at a dose of 2.5, 5 or 10 mg/kg body weight/day for 24 days. The creatinine (Cr) level was also significantly decreased in rats given 5 and 10 mg of this compound. A significant decrease in urea nitrogen, MG, and GSA was found in rats given 6.25 mg of procyanidin B-2 3,3'-di-O-gallate. However, unlike the former two components the administration of 12.5 mg of procyanidin C-1 3,3',3''-tri-O-gallate produced a considerable or significant increase in bLood levels of urea nitrogen, Cr, MG, and GSA. RG-tannin had a weaker overall effect on serum constituents except for GSA in comparison with the corresponding effect of (-)-epicatechin 3-O-gallate and 6.25 mg of procyanidin B-2 3,3'-di-O-gallate. Rhatannin tended to increase the serum nitrogen constituents.

Animals↗

Application of an interleukin 2 slow delivery system to the immunotherapy of established murine colon 26 adenocarcinoma liver metastases.

We evaluated the antitumor effect of an interleukin 2 (IL-2) slow delivery system, the IL-2 minipellet, using a murine hepatic metastasis model. The IL-2 minipellet consists of atelocollagen derived from natural bovine skin together with 1 x 10(6) units of recombinant IL-2. Administration of the IL-2 minipellet was performed into the spleens of BALB/c mice after translocation of the spleens to the s.c. position. Administration produced detectable serum IL-2 levels for 72 h. The IL-2 minipellet was evaluated for its efficacy against hepatic metastases from colon 26 adenocarcinoma in the BALB/c mice. Both the administration of the IL-2 minipellet alone and its combination with the injection of 5 x 10(7) lymphokine-activated killer cells resulted in significant reductions of the number of metastatic nodules. Moreover, increased survival of mice bearing colon 26 adenocarcinoma was noted in these two treatment groups. To investigate the mechanism of the IL-2 minipellet activity, we tested the lytic potential of splenocytes obtained after administration of the IL-2 minipellet in a 51Cr release assay. Cytotoxicity against YAC-1 cells and colon 26 cells was significantly augmented on Day 2 after minipellet administration. These results demonstrated that local administration of the IL-2 minipellet into the hepatic circulation was extremely effective against metastatic liver cancer.

Adenocarcinoma↗

Determination of pulmonary microvascular reflection coefficient in sheep by venous occlusion.

We devised a technique that permitted elevation of pulmonary pressures in unanesthetized sheep by occluding their pulmonary veins. Using this technique, we raised pulmonary capillary pressure from a baseline of 13.2 +/- 2.2 to 35.3 +/- 5.1 mmHg. This increased lung lymph flow (from 8.8 +/- 2.7 to 53.1 +/- 13.9 ml/h). We estimated the pulmonary microvascular oncotic reflection coefficient and found it to be 0.82 +/- 0.05 (SD). The filtration coefficient was 0.019 +/- 0.005 ml.mmHg-1.min-1. During the period of increased pressure, the animals had stable arterial pressures and cardiac outputs. None of the animals developed blood coagulation problems. These data illustrate the usefulness of pulmonary venous occlusion to elevate pulmonary microvascular pressure to obtain plasma-to-lymph protein concentration ratios independent of flow, allowing for the calculation of the oncotic reflection coefficient.

Animals↗

Functional changes of aorta with massive accumulation of calcium.

The present study was undertaken to elucidate pathophysiological changes and functional alterations of the calcified artery. For this purpose, rats were treated with 500,000 units/kg vitamin D3, and tension development of isolated rat aortae was examined. Treatment of rats with vitamin D3 resulted in an increase (approx. 64-fold) in the tissue calcium. Light microscopic examination of the aorta after staining with hematoxylin-eosin and von Kossa indicated numerous plaques in the aortic media. The results indicate a massive accumulation of calcium in the aortic media. Responsiveness of the calcified tissue to norepinephrine, epinephrine, serotonin, prostaglandin F2 alpha was found to be 11-66% when compared to that of the control. Furthermore, the calcified tissue responded minimally to isoproterenol and acetylcholine, which elicited a relaxation in control aortae. Isoproterenol-induced relaxation of the calcified aorta after 100 mM KCl contracture was also diminished. In the present study we have demonstrated poor responsiveness of the calcified aorta to physiological and pharmacological substances relative to normal tissue, which implies a functional damage of the artery upon massive calcium accumulation.

Acetylcholine↗

Clinical use of the measurement of airway resistance during spontaneous respiration.

Airway resistance was measured during spontaneous respiration in healthy smokers and patients with chronic obstructive pulmonary disease, and the relationship between the airway resistance and respiratory frequency was examined. No significant difference was observed between the airway resistance in smokers and nonsmokers. In the chronic obstructive pulmonary disease group, patients with pulmonary emphysema had highest airway resistance. The determination of airway resistance during spontaneous respiration appears to be a very useful, noninvasive method of pulmonary function testing.

Adult↗