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Biomedical subjects

Y Kawase

Publications and source records attributed to Y Kawase.

At least 73 records · Page 4Linked to original sources

In vitro effects of OK-432 on irradiated mouse bone marrow cells.

PURPOSE: In vitro effects of OK-432 on irradiated mouse bone marrow cells are examined. METHODS AND MATERIALS: Bone marrow cells of BDF1 mouse (1 x 10(6) cells/ml) were incubated with alpha medium, 2% fetal calf serum and OK-432 in a CO2 incubator at 37 degrees C for 24, 48 and 72 h, respectively. After centrifugation, each supernatant was collected and used for conditioned medium in CFU-GM assay: Changes in CFU-GM as a function of incubation time and OK-432 dose was examined; changes of CFU-GM according to various doses of OK-432 were examined in two mouse strains, BDF1 and BALB/c mouse; changes in protective effect of OK-432 in terms of CFU-GM as a function of administration timing of OK-432 in relation to irradiation. As a radiation source, 137Cs at a dose rate of 500 cGy/min was used. RESULTS: The CFU-GM decreased with the incubation time when OK-432 was not administered, while it significantly increased with incubation time when OK-432 was added at 0.5 and 1.0 KE/ml at 48-72 h of incubation. The former showed marked increase at 48-72 h of incubation. CFU-GM of BDF1 mouse was always higher than that of BALB/c mouse for any dose of OK-432. CFU-GM per femur according to the timing of administration of OK-432 from 24 h before to 24 h after irradiation showed 10299 +/- 2300 (24 h before), 10783 +/- 2463 (3 h before), 10045 +/- 1501 (immediately after), 8504 +/- 1188 (3 h after), 4898 +/- 1212 (6 h after), 1214 +/- 736 (12 h after) and 181 +/- 113 (24 h after irradiation), respectively. CONCLUSION: OK-432 stimulates cultured mouse bone marrow cells to produce GM-CSF in vitro by direct contact action. This direct stimulating action of OK-432 on GM-CSF production of bone marrow cells can be kept from 24 h before to at least 3 h after irradiation.

Animals↗

Slow relaxation process in the main transition of phosphatidylcholines studied with heat capacity spectroscopy. I. Multilamellar vesicles.

Extremely slow relaxation processes have been examined near the main transition of multilamellar vesicle samples of dimyristoylphosphatidylcholine (DMPC) and dipalmitoylphosphatidylcholine (DPPC) with a heat capacity spectroscopic technique. The dynamic heat capacity showed a significant frequency dependence in the studied frequency region of 0.5 mHz to 50 mHz. The relaxation observed here has been analyzed with the Cole-Cole equation. The mean relaxation times were 120 s in DMPC, and 260 s in DPPC. The relaxation showed a polydispersive character. The parameter beta was around 0.5 in both DMPC and DPPC.

1,2-Dipalmitoylphosphatidylcholine↗

An alpha-fetoprotein producing pancreatic cystadenocarcinoma.

An autopsy case of an 83-year-old Japanese woman with pancreatic cancer with significantly elevated serum alpha-fetoprotein levels is reported. The pancreatic tumor was a mucinous cystadenocarcinoma with multiple metastasis to the liver. The immunohistochemistry for alpha-fetoprotein revealed positive reactivity in the cytoplasm of cancer cells in the primary and liver metastatic lesions. The current case is the first reported in which mucinous cystadenocarcinoma of the pancreas produced alpha-fetoprotein.

Aged↗

Improved method of preparation of inflated-fixed lung for radiologic-pathologic correlation.

The technique of inflation and fixation of the lung with polyethylene glycol is useful for specimen radiography and radiologic-pathologic correlation, but it is limited by poor histologic staining of the fixed tissue. To improve staining we used formalin to distend and fix the lung before standard fixation with a polyethylene glycol mixture. In this preliminary study, canine and infant lungs, and lungs from three cases of lung cancer were examined. The modified technique provided high-quality staining and satisfactory specimen radiography in all cases except one of the lung cancers; in this case excessive shrinkage occurred and degraded radiographic quality. We conclude that the new method of preparation permits both specimen radiography and high quality staining of the fixed tissue.

Adult↗

Assessment of left ventricular filling dynamics utilizing Doppler echocardiography in acute coronary syndrome.

To evaluate prolonged diastolic dysfunction in acute coronary syndrome, mitral inflow velocities and left ventricular wall motion were examined with pulsed-wave Doppler and two-dimensional echocardiography in 14 patients with successful reperfusion, 8 patients without reperfusion after acute myocardial infarction, and in 10 patients with prolonged angina. Early peak flow velocity and the ratio of early to atrial peak flow velocity increased gradually both after the onset of acute myocardial infarction with reperfusion and cessation of angina pectoris. However, in acute myocardial infarction without reperfusion, early peak flow velocity and the ratio of early to atrial peak flow velocity decreased significantly. Atrial peak flow velocity remained unchanged in acute myocardial infarction with reperfusion, while it was decreased in angina pectoris on the seventh day. Regional systolic dysfunction abated gradually in acute myocardial infarction with successful reperfusion, and regional systolic dysfunction was not detected in angina pectoris on the third day. Thus, abnormalities in left ventricular early diastolic filling persisted for several days after reperfusion in acute myocardial infarction or cessation of angina. Left ventricular late filling remained unchanged in acute myocardial infarction, whereas, in angina pectoris, a compensatory increase in late filling diminished gradually with an increase in early filling. These results indicate that there are different types of recovery process after diastolic filling abnormalities in patients with acute coronary syndrome.

Angina Pectoris↗

Does preconditioning affect recovery in stunned myocardium?

In this study, to determine whether preconditioning enhances the process of recovery from post-ischemic dysfunction, ultrasonic crystals were placed in 8 open-chest dogs to measure regional myocardial wall thickening in the ischemic area. A carotid-circumflex coronary artery bypass was created with an electromagnetic flow probe and a fixed stenosis was produced. Ventricular pacing was performed for 15 minutes at a rate of 190-220 bpm. After a 15 minutes rest period, a second pacing was performed in a similar manner. After cessation of the first pacing, circumflex wall thickening remained reduced significantly. Three minutes after cessation of the second pacing, circumflex thickening decreased further. After 15 minutes, wall thickening improved to the value recorded before the second pacing. The degree of improvement from 3 minutes to 15 minutes after the second pacing was greater than that after the first pacing. Thus, preceding demand ischemia modifies the rate of functional recovery from the next post-ischemic dysfunction, indicating that preconditioning of the ischemic myocardium enhances recovery from stunning.

Animals↗

[anorexia nervosa; an association with certain types of soft tissue emphysema].

A 17-year-old female with anorexia nervosa developed pneumomediastinum, subcutaneous emphysema, retroperitoneal emphysema, interstitial pulmonary emphysema and epidural emphysema (epidural emphysema; air between the dura mater and the vertebral arch). She had no history of bronchial asthma. The mechanism was presumed to be weakness of the alveolar wall due to malnutrition, leading to rupture of alveoli, followed by air entering the interstitium and dissecting along perivascular sheaths (interstitial pulmonary emphysema) into the mediastinum. A further increase in mediastinal pressure may bring about opening of the fascial planes along great vessels and allow air to penetrate into subcutaneous tissues and the spinal canal. These types of emphysema have been reported in bronchial asthma cases and in those on positive pressure breathing. To our knowledge, there are no previous reports of anorexia nervosa associated with these phenomena.

Adolescent↗

Effect of human recombinant granulocyte colony-stimulating factor on induction of myeloid leukemias by X-irradiation in mice.

Hematopoietic suppression is one of the serious problems induced by whole body irradiation. Granulocyte colony-stimulating factor (G-CSF) stimulates the progenitors of granulocytes and accelerates their recovery from bone marrow suppression induced by cytotoxic chemotherapy or radiation. On the other hand, G-CSF stimulates proliferation of myeloid leukemia cells as well as normal granulocytes in vitro. We designed a method to determine if G-CSF affects the incidence of myeloid leukemias induced by irradiation and the types of leukemias induced according to the French-American-British (FAB) classification in RFM/MsNrs mice. Administration of G-CSF (2 micrograms/d for 7 days) after a single 3-Gy irradiation significantly increased the number of peripheral blood neutrophils as compared with those in control mice. Even after discontinuation of G-CSF, both the total leukocyte and neutrophil counts increased to day 10, and their levels remained elevated until day 14. The incidence of myeloid leukemia in mice exposed to a single 3-Gy irradiation was 18.6% (38 of 204), and treatment with G-CSF did not increase the incidence (15.7% [32 of 204]). In the mice with radiation-induced leukemia, those receiving G-CSF had a mean survival time of 357 days, whereas those not receiving the factor survived for 349 days. There was no significant difference of survivals between the two groups. Most of the radiation-induced leukemias in the two groups were M1 or M2, according to the FAB classification; no characteristic difference was observed among the types of leukemias. Although G-CSF stimulated the leukemia cells in vitro, G-CSF administration after irradiation did not increase the occurrence of radiation-induced myeloid leukemias. Our results show that administration of G-CSF effectively accelerates neutrophil recovery from irradiation-induced hematopoietic injury and does not enhance the induction of myeloid leukemia in RFM/MsNrs mice by irradiation.

Animals↗

Effect of polymer additives on hydrodynamics and oxygen transfer in a bubble column bioreactor.

The influence of polymer additives (polyethylene oxide and polyacrylamide) on the hydrodynamics and oxygen transfer in a bubble column bioreactor was examined. The addition of small amounts of these polymers has been known to cause significant drag reduction in turbulent flow circumstances. The gas hold-up was slightly decreased and the liquid-phase mixing was somewhat enhanced due to the addition of the polymers. The addition of polymer additives brought about a reduction of the volumetric oxygen transfer coefficient by about 40%. In dilute polymer solutions, large bubbles formed by bubble coalescence moved with high rise velocities in the presence of many small bubbles and the bubble size distributions were less uniform compared with those in water. The complicated changes in bubble hydrodynamic characteristics were examined to give possible explanations for oxygen transfer reduction.

Acrylic Resins↗

Association of IgG anti-GD1a antibody with severe Guillain-Barré syndrome.

We earlier reported cases of 2 patients with severe acute Guillain-Barré syndrome (GBS) associated with high-IgG anti-GD1a antibody titer. We now have investigated the autoantibody against GD1a or GM1 in 37 GBS patients using the enzyme-linked immunosorbent assay and have found a statistically significant association between IgG anti-GD1a antibody and the severity of the disease (need of a respirator for more than 1 month and a poor functional prognosis 3 months after neurologic onset). An autopsy which showed severe GBS associated with IgG anti-GD1a antibody produced the following findings: (1) severe axonal degeneration and segmental demyelination of peripheral nerves; (2) lymphocytic infiltration; and (3) marked central chromatolysis of the lower motoneurons.

Adolescent↗

Case report: silent thyroiditis developed during alpha-interferon therapy.

Alpha-interferon (IFN-alpha) was used for the treatment of chronic active hepatitis C in a 30-year-old woman who was euthyroid but had low titers of antithyroid antibodies before treatment. Two months after the initiation of IFN-alpha therapy she became thyrotoxic. She had nontender diffuse goiter. A laboratory examination revealed elevated levels of serum free thyroid hormones and a suppressed concentration of serum thyrotropin. Titers of antimicrosomal antibodies increased. The anti-thyrotropin receptor antibody was negative. A 99mTcO- scintigram of the thyroid showed reduced uptake. During the IFN therapy free thyroid-hormone levels started to decline. The IFN-alpha therapy was completed 1 month after the onset of thyrotoxicosis. Two months after the completion of the therapy the patient became euthyroid and 99mTcO- uptake was normalized. It is likely that preexisting chronic thyroiditis was exacerbated to cause silent thyroiditis during IFN-alpha therapy. None of the other 11 patients with chronic hepatitis C who had had no anti-thyroid antibodies and were treated with IFN-alpha showed anti-thyroid antibodies and thyroid dysfunction after the therapy. It is advisable to assess anti-thyroid antibodies and thyroid function in patients who are going to receive IFN-alpha treatment.

Adult↗

Impaired early and intact late diastolic function in stunned myocardium induced by demand ischemia.

Changes in left ventricular diastolic properties of pacing-induced stunned myocardium were examined in 10 anesthetized dogs instrumented with a micromanometer for left ventricular pressure and sonomicrometers for left ventricular short axis, anterior and posterior segment lengths, and posterior wall thickness. After the creation of a critical stenosis on a carotid-circumflex coronary artery bypass, left ventricular pressure and dimensions were recorded simultaneously during temporary superior and inferior vena caval occlusion to allow for the construction of end-diastolic pressure-segment length curves. After 15 min of high-frequency pacing (190-220 beats/min), measurements were repeated and compared with those before pacing. The mean lengthening rate of each dimension during the first half of diastole was calculated as an index of early diastolic function. Three minutes after the end of pacing, coronary blood flow and perfusion pressure were unchanged, whereas systolic function of the posterior wall was depressed, indicating stunning of the posterior myocardium. The time constant of left ventricular pressure decay was prolonged by 14%. The mean lengthening rate during the first half of diastole decreased by 50% in the left ventricular internal short axis and by 119% in the posterior segment. Despite the significant impairment of early diastolic function, the regional end-diastolic pressure-segment length relation of the posterior wall was unchanged. Thus, in contrast to the results reported for pacing-induced ischemia that were measured immediately after pacing, the distensibility of the left ventricular wall in stunned myocardium induced by pacing was unchanged despite depressed early diastolic function.

Animals↗

[Prolonged diastolic stunning after unstable anginal attacks].

To evaluate the changes in the left ventricular diastolic filling dynamics after severe myocardial ischemia, serial pulsed Doppler examinations of mitral flow were performed in 10 patients with unstable angina. Peak early and late filling velocities (E and A), the ratio (E/A), the area E (Ei) and A (Ai) and the ratio (Ei/Ai) were measured one, 3, and 7 days and one month after the last ischemic episode. Seven of 10 patients were treated with percutaneous transluminal coronary angioplasty (PTCA), and the same indexes were obtained one, 3, and 7 days and one month after PTCA. E/A and Ei/Ai increased significantly on the 3rd and 7th days, however, no further increase was observed one month after the last ischemic episode and after PTCA. Left ventricular diastolic dysfunction induced by severe myocardial ischemia persisted for several days after the stabilization of myocardial ischemia. After the ischemic episodes were stabilized by administering pharmacological therapy, left ventricular diastolic dynamics were unchanged before and after PTCA. These results indicate that there may be diastolic myocardial stunning in patients with unstable angina.

Angina, Unstable↗

[Visual acuity testing of three-year-old children using Landolt ring and picture targets].

Visual acuity testing using Landolt ring and picture targets (silhouettes of butterfly, fish, bird and tulip), was performed on 184 three-year-old subjects who had received secondary ophthalmic examination at the age of 3 years and 1-3 months, and the results were evaluated. The examinations were feasible on 83.1% of the subjects for the picture test and 76.1% for the Landolt ring test; the picture test being significantly higher. However, when the level was set at 0.5, namely, 0.5 or more were judged as "passing" and less than 0.5 judged as "failing", the Landolt ring test showed a significantly higher rate than the picture test in the number "passing". Specificity and sensitivity were calculated with reference to the clinical findings. Results suggest that the Landolt ring test has a better validity than the picture test and the Landolt ring test could differentiate between good and poor vision. The silhouette of the bird was particularly poor. When using picture targets for testing, the necessity of proper selection of the kind of pictures used is indicated. In the case of use of the Landolt ring, reexamination at the age of 3 years and 6 months or later, or postponement of the examination until age 3 years and 6 months or later would appear to be beneficial for enhancing the feasibility of the test.

Child, Preschool↗

[A case of treating abrupt closure due to post PTCA dissection by emergent CABG-reoperation, via extracorporeal circulatory method conducted with the heart "beating"].

A female patient, 73 years of age, who underwent CABG for the RCA and First Diagonal Branch by SVG 39 months ago was readmitted to our clinic after an onset of acute angina pain, whereupon successful PTCA was performed to Cx segment 13. However, with the angina pain continuing unabated, and with the recognition through emergent CAG that the graft to the RCA was occluded. PTCA was performed again to the RCA segment 1. The segment was closed off by dissection. The emergent CABG was carried out via femoro-femoral extracorporeal circulation and intra aortic balloon pumping. This CABG was of a RCA to RCA bypass nature, with SVG performed with the heart "beating" and without cooling. The patient was thus relieved of her angina pain and her cardiac function has since been in good order.

Aged↗

[Visual acuity testing of three- and four-year old nursery school and kindergarten children].

Visual acuity testing was conducted on 1,531 children in nursery schools and kindergartens in Chita district, for the purpose of determining the rate of successfully performing the test, as well as the visual acuity of those shown to be normal by various ophthalmologic examinations. The rate of successful performance of the visual acuity test increased monthly with increasing age, with maximum changes seen at 4-5 months after the third birthday. The rate of successful performance of the test at the third birthday was 73%, progressively increasing up to 95% in the successive 6 months. The rate at the fourth birthday became almost 100%. Average of visual acuity of 3.0-year old children was 0.55, and for 3.5-year olds was 0.82. The average visual acuity reached 0.88 at 4.0 years of age, and at 4.5 years of age became 0.97. In view of the results obtained, it is concluded that children who could not successfully perform a visual acuity test at 3.0-years of age should be tested again at 3.5-years of age. Preferably the vision screening should be performed during the period between 3.5- and 4.0-years of age, for reliability and efficiency. Accordingly, the screening standards should also be changed with consideration given to visual development of children of this age.

Child↗

Construction and characterization of a fusion protein with epidermal growth factor and the cell-binding domain of fibronectin.

An efficient expression system was constructed for C-EGF, a fusion protein made of a fragment of the cell-binding domain of human fibronectin (FN) bound with epidermal growth factor (EGF). C-EGF was produced in Escherichia coli HB101 cells carrying the recombinant plasmid pCE102 as inclusion bodies, which were solubilized and refolded after purification. C-EGF had both cell-adhesive and EGF activities, so it might be more effective than EGF in therapeutic applications. This fusion system would be useful for the construction of a recombinant drug delivery system for cells that have fibronectin receptors (integrins).

Cell Adhesion↗