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Biomedical subjects

M Okada

Publications and source records attributed to M Okada.

At least 163 records · Page 9Linked to original sources
PubMed2001

Changes in pattern of immunoglobulin heavy chain gene rearrangement and MIB-1 staining before and after eradication of Helicobacter pylori in gastric mucosa-associated lymphoid tissue (MALT) lymphoma.

Gastric low-grade mucosa-associated lymphoid tissue (MALT) lymphomas are strongly associated with infection by Helicobacter pylori (H. pylori). Antibiotic treatment for H. pylori induces a sustained remission in a significant number of patients. We report here the outcome in 13 patients with gastric low-grade MALT lymphomas or suspected gastric lesions, treated for eradication of H. pylori. Patients were followed closely with sequential histological studies, polymerase chain reaction (PCR) amplification of the immunoglobulin heavy chain (IgH) gene and immunohistochemistry for MIB-1. Antibiotic therapy resulted in eradication of H. pylori in all but one case, as assessed histologically. In 12 cases with successful eradication, complete regression was observed histologically in 9 cases (75%) and no regression in 3 (25%). In 7 of 9 (78%) patients who had a complete remission, clonal bands of IgH gene detected on PCR before therapy disappeared after therapy. All 9 patients with complete regression showed a reduced number of MIB-1 positive cells, while 4 cases with no change or disease progression showed no change or increased number of MIB-1 positive cells. There was a strong relationship between density of MIB-1-positive cells and histological score. These results indicate that combination analysis of PCR of IgH and MIB-1 seems to represent a very good current approach for the diagnosis of gastric low-grade MALT lymphoma and to assess the effects of chemotherapy, especially in problematic cases.

Aged↗
PubMed2001

Vascular reconstruction of a vertebral artery loop causing cervical radiculopathy and vertebrobasilar insufficiency. Case report.

The authors present the case of a 62-year-old man with a 4-month history of progressive left-sided C-5 radiculopathy and dizziness. Neuroimaging studies revealed a looped vertebral artery (VA) that had migrated into the widened left C4-5 intervertebral foramen. The patient underwent vascular reconstruction of the VA loop, in which there was minimal manipulation of the C-5 nerve root, via a left-sided anterolateral approach after a balloon occlusion test. Postoperatively the patient's symptoms improved immediately, and there were no signs of recurrence within the 2-year follow-up period. This excellent outcome supports the belief that a proper surgical reconstruction of the compressive, tortuous VA should be the therapeutic option of choice, which carries a lower risk of the nerve root injury and improves the hemodynamics in the posterior circulation.

Angiography↗
PubMed2001

Effect of exercise on the metabolism of vitamin B6 and some PLP-dependent enzymes in young rats fed a restricted vitamin B6 diet.

The effect of exercise on vitamin B6 metabolism and PLP-dependent enzymes was studied in rats fed a diet with or without vitamin B6. Metabolism of some amino acids (citrulline, arginine, ornithine and threonine) inhibited in the B6-deficient rats was normalized during exercise. Exercise was also effective in storing vitamin B6 in the body by lowering excretion of vitamin B6, when intake of vitamin B6 was restricted. Aspartatae aminotransferase activity was higher in the red portion of the gastrocnemius muscle than that of the white one, whereas glycogen phosphorylase activity was vice versa and furthermore glycogen content in the white portion was very low in the vitamin B6-deficient rat. From the data obtained, it has been suggested that the red and white portions of the gastrocnemius muscle seemed to be more important in metabolizing amino acids and hydrolyze glycogen, respectively.

Adaptation, Physiological↗
PubMed2001

Nutritional effects of cyclodextrins on liver and serum lipids and cecal organic acids in rats.

The effect of dietary cyclodextrins on liver and serum lipids and cecal organic acid production was investigated. Male Wistar rats were fed a basal diet and a diet containing 5% of alpha-, beta-, or gamma-cyclodextrin. The body weight gain in rats fed the alpha-cyclodextrin diet was not significantly different from rats fed the other three kinds of diets. The feeding of dietary alpha-cyclodextrin increased total lipid and phospholipids in the liver. Beta-cyclodextrin significantly lowered serum total cholesterol and phospholipid levels compared with the basal diet et al. A decrease in serum triacylglycerol levels was also observed in beta-cyclodextrin-fed rats. Dietary alpha-cyclodextrin significantly increased the weight of cecal tissues and contents, and an approximate fourfold increase in acetate, propionate, and total organic acids was noted, indicating the fermentibility of beta-cyclodextrin compared with the basal diet. It seems likely that the suppression of serum cholesterol levels by alpha- and beta-cyclodextrins might be due to the increasing acetate and propionate productions in the cecum. cecal organic acid, cyclodextrin, serum cholesterol, rats

Acetates↗
PubMed2001

[Modification of HPLC conditions for the determinations of raw materials, intermediates and subsidiary colors in 5 kinds of food azo colors].

Modification of HPLC conditions for the determinations of raw materials, intermediates and subsidiary colors (organic impurities) in 5 kinds of food azo colors were studied in order to analyze them simply and rapidly. The organic impurities were determined by HPLC using L-column ODS and a gradient system (0.02 mol/L ammonium acetate solution for 10 min, and a gradient with a mixture of acetonitrile and water (7:3)). The organic impurities in 163 samples of azo colors subjected to inspection in fiscal year 1999 were determined under the proposed HPLC conditions. It was found that the contents of organic impurities in 163 samples were less than the limit of Japan's Specifications and Standards for Food Additives, 7th Edition.

Azo Compounds↗
PubMed2001

[An autopsy case of primary aortoduodenal fistula complicated by both gastric carcinoma and acute gastric mucosal lesions].

We present an autopsy case of aortoduodenal fistula complicated by both gastric carcinoma and acute gastric mucosal lesions(AGML). A 73-year-old man with a past history of gastric ulcer, myocardial infarction, and arteriosclerosis of the right femoral artery presented to Osaka National Hospital complaining of intermittent claudication of the right lower extremity. After a diagnosis of arteriosclerosis obliterans, percutaneous angioplasty was performed. The postoperative course was initially good. However, two weeks after the angioplasty procedure he suddenly vomited blood. Emergency endoscopy revealed both polypoid gastric carcinoma and AGML, which were considered to be the major cause of his gastrointestinal bleeding. And he died of uncontrollable gastrointestinal bleeding two weeks after this examination. Autopsy showed an atherosclerotic aneurysm of the abdominal aorta that had ruptured into the third part of the duodenum. To our knowledge, there has been no previous autopsy on a primary aortoduodenal fistula from an atherosclerotic abdominal aneurysm complicated by similar hemorrhagic gastric lesions. This case emphasizes the difficulty of making a clinical diagnosis of primary aortoduodenal fistula.

Acute Disease↗
PubMed2001

[Relationship between keeping a companion animal and instrumental activity of daily living (IADL). A study of Japanese elderly living at home in Satomi Village].

OBJECTIVE: The purpose of this study was to clarify the relationship between the companionship of an animal and the level of Instrumental Activity of Daily Living (IADL) of elderly people living at home, and to consequently determine beneficial effects on the overall health of the elderly. METHODS: For this study, 400 elderly people aged 65 years and over were randomly selected from among the 1,345 citizens of Satomi Village, Ibaraki Prefecture. Self-administered questionnaires were mailed to the selected subjects in March of 1999. In the survey, the respondents were asked if they could accomplish all seven IADL activities. Subjects for whom this was the case were classified as having no IADL disability. Elderly who answered "No" for even one were listed as having an IADL disability. Using the existence of an IADL disability as a dependent variable and various factors related to companion animals as independent variables, a logistic regression analysis was performed. RESULTS: Out of the 400 individuals, 84.8% responded. With respect to the possession of a companion animal, the number of participants who never had a companion animal was 115 (35.8%); while 118 (36.8%) possessed a companion animal in the present. With regard to factors relevant to IADL of elderly people, the odds ratio (OR) adjusted for age and sex for participants who owned dogs was 0.53 (95% confidence interval [CI] 0.27-0.99) relative to those who never had a companion animal: The difference was significant. For those respondents who indicated that their companion animals were their best friends, the OR was 0.48 (95% CI 0.23-0.99), and again significant. The OR tended to decrease with increase in the duration of owning a companion animal. CONCLUSION: In this study, owning a dog and everyday contact with the companion animal were related to the IADL of the elderly living at home. It is possible that keeping a companion animal may be linked to better overall health in the elderly.

Activities of Daily Living↗
PubMed2001

Neurometer measurement of current stimulus threshold in rats.

We examined the current stimulus threshold in rats with the Neurometer, a device used clinically for measuring perception and pain thresholds. Although many studies have indicated the usefulness of this device in the quantification of nerve dysfunction in patients, we have found no published reports on the use of the Neurometer in animals. Transcutaneous nerve stimuli of the three sine-wave pulses produced by the Neurometer (at 2000, 250, and 5 Hz) were applied to plantar surface of rats. The intensity of each stimulation at which rats vocalized or were hardly startled was defined as the current stimulus threshold. With repeated stimulation, the thresholds were almost constant. Repeated topical application to the area around the stimulating electrode of a high concentration of capsaicin, which acts on small-diameter fibers, increased the thresholds at 250 and 5 Hz, but did not affect the 2000-Hz threshold. Intravenous morphine (2-5 mg/kg) increased all three thresholds, whereas intrathecal morphine (20 or 80 microg) increased only the 5-Hz threshold. Intravenous injection of a minor tranquilizer, diazepam, at 1 mg/kg raised the thresholds at 2000 and 250 Hz, but did not affect the 5-Hz threshold. Higher dose of diazepam increased all three thresholds. These results suggest that the Neurometer makes possible selective examination of subsets of nerve fibers that differ in diameter not only in humans but also in animals. The present study in rats, in which we established a method of measurement, may provide helpful suggestions for the interpretation of data in humans.

Animals↗
PubMed2001

[Transitional pre-B-cell ALL].

An 18-month-old girl was referred to our hospital because of fever and pancytopenia. On admission, her bone marrow nuclear cell count was 45,000/microliter, being mostly blasts with cleaved nuclei. The leukemic cells were negative for peroxidase staining, expressed CD10, CD19, CD34 and sIg mu, and did not express sIg kappa and lambda, corresponding to a minor subpopulation of B cells known as transitional pre-B-cells (TPBs). Since TPB-ALL has been reported only infrequently, the incidence and clinical picture of this rare type of ALL are still uncertain. Extensive immunophenotypic studies to determine the expression of sIg mu, sIg kappa and lambda will provide accurate diagnosis, which is essential for effective management of this condition.

Antigens, CD19↗
PubMed2001

Lipid microspheres incorporated by U937 cells via their specific receptors.

Lipid microspheres (LM), currently in clinical use as drug carriers, mainly consist of soybean oil as a core and lecithin as a surfactant. The purpose of our study wass to determine whether or not LM incorporation is receptor-mediated. U937 cells resuspended in a serum-free medium abundantly took up unmodulated LM. A binding study showed that U937 cells had a single binding site for LM (410 sites/cell at 24 degrees C; 100 sites/cell at 4 degrees C). Inhibition assays revealed that lecithin liposome, lysophosphatidylcholines, activated alpha2-macroglobulin, and HDL did not affect the binding of LM to U937 cells. VLDL strongly, and LDL and AcLDL moderately, inhibited the binding of LM to U937 cells. Ligand blotting analysis revealed that unmodulated LM in an apoprotein-free buffer directly bound to a 40 kDa protein in the cell membrane fraction. These results suggest that LM that is not modulated by any protein is incorporated by specific cells via receptor-mediated processes.

Binding Sites↗
PubMed2001

Effects of spilled oil on the tidal flat ecosystem--evaluation of wave and tidal actions using a tidal flat simulator.

The purpose of this study is to clarify the effects of wave and tidal actions on the penetration of spilled oil stranded on tidal flats and to evaluate the influence of the penetrated oil on seawater infiltration using tidal flat simulator. A simulator used was composed of tidal flat, wave maker, tide controlling device, temperature controlling system and computer controlling system. The infiltrations of seawater and fuel oil C into tidal flats were visualized using transparent glass beads as tidal flat sediments. Penetration behaviour of the spilled oil into the sediments was significantly different from that of seawater. Seawater infiltrated into the sediments both by wave action and tidal fluctuation, while fuel oil C penetrated by tidal movement only. The infiltration of seawater was reduced by penetrated oil. This result indicates that the penetrated oil diminishes infiltration of seawater into the sediments and thus results in the reduction in the supply of oxygen, nutrients, and organic matter to the benthic organisms in tidal flat.

Animals↗
PubMed2001

[Pulmonary hypertension associated with refractory hyperthyroidism: a case report].

A 25-year-old woman was admitted to our hospital with goiter. The diagnosis was Grave's disease. Diagnostic transthoracic echocardiography revealed a hyperdynamic stage of the heart with right ventricular dilation. Doppler echocardiography showed mild to moderate tricuspid regurgitation and elevated systolic right ventricular pressure. Right heart catheterization revealed high cardiac output (9.49 l/min) and pulmonary hypertension (57 mmHg) with increased pulmonary vascular resistance and total pulmonary resistance. No intracardiac shunts were detected. Since neither thiomazole nor propylthiouracil was effective and both caused side effects, she underwent subtotal thyroidectomy. After the surgery, pulmonary hypertension improved and cardiac output normalized, but without normalization of pulmonary vascular resistance and total pulmonary resistance. Reversible pulmonary hypertension may occur in patients with hyperthyroidism. Increased pulmonary blood flow and sustained high pulmonary artery resistance were suspected as the causes of pulmonary hypertension. In addition, pulmonary endothelial dysfunction as a result of sustained increased pulmonary blood flow could be another cause of pulmonary hypertension.

Adult↗
PubMed2001

Differences in prolonged ischemia length using ischemic preconditioning in the rabbit heart. Tolerable limitation time for surgically induced myocardial ischemia during normothermic cardiac operation.

BACKGROUND: To determine the effect of the tolerable limitation time of prolonged ischemia after ischemic preconditioning on postischemic functional recovery and infarct size reduction in the rabbit heart. METHODS: White rabbits (n=30) were used for Langendorff perfusion. Control hearts were perfused at 37 degrees C for 180 min; 30 min global ischemia hearts (30GI) received 30 min global ischemia and 120 min reperfusion; IPC+30GI hearts received 5 min zero flow global ischemia and 5 min reperfusion prior to 30 min global ischemia; 20 min global ischemia hearts (20GI) received 20 min global ischemia and 120 min reperfusion; IPC+20GI hearts received 5 min zero flow global ischemia and 5 min reperfusion prior to 20 min global ischemia. RESULTS: Infarct size in the 30GI hearts was 33.5+/-4.0% and 1.7+/-0.5% in the control hearts. The 20GI hearts and IPC+30GI hearts decreased infarct size, as compared with the 30GI hearts (13.0+/-1.8% and 16.6+/-1.7%, respectively; p<0.001, 20GI vs 30GI; p<0.01, IPC+30GI vs 30GI; p>0.05, 20GI vs IPC+30GI) but did not enhance postischemic functional recovery. The IPC+20GI hearts (3.5+/-0.6%) significantly decreased infarct size as compared with the 20GI hearts (p<0.05, IPC+20GI vs 20GI), and there was no significant difference between the IPC+20GI and the control hearts (p>0.05), but the IPC+20GI hearts did not enhance postischemic functional recovery. CONCLUSIONS: A 20 min ischemia may be the tolerable limitation time of prolonged ischemia after ischemic preconditioning in an isolated rabbit heart model.

Animals↗
PubMed2001

Coronary artery bypass grafting in a patient with brainstem ischemia.

We describe a 54-year-old male with severe coronary artery disease and cerebrovascular disease including right cerebellar infarction, total occlusion of the bilateral vertebral arteries, brainstem ischemia, and right cerebral infarction with significant right carotid artery disease. Repeated percutaneous transluminal coronary angioplasty had been performed, however, unstable angina was developed despite maximal medical treatment. Coronary artery bypass grafting was successfully undergone with use of propofol, application of the intra-aortic balloon pumping perioperatively, and mild hypothermic cardiopulmonary bypass with alpha-stat blood gas management. The importance of preoperative evaluation of the intracranial circulation and management of cardiopulmonary bypass are discussed.

Angina, Unstable↗
PubMed2001

[Effectiveness of Saiko-Keishi-To (TJ-10, a Kampo herbal medicine) for trigeminal neuralgia in rats].

It is known that Saiko-Keishi-To (TJ-10), a Kampo herbal medicine used for the treatment of epilepsy, shows a satisfactory curative effect even in the patients suffering from trigeminal neuralgia. To verify the effectiveness of TJ-10, Wistar rats with chronic neuralgia of the mandibular nerve were prepared and TJ-10 was administered to them for 4 weeks following the manifestation of pain in the mandibular region. The result reveals that the rise in the pain threshold in the mandibular region is more significant in the rats administered TJ-10 than in those in the control group. However, in the tail flick test, no significant change was observed in the pain threshold. These findings suggest that TJ-10 is effective for controlling the manifestation of pain in ligatured nerves, by local effect, not by general analgesic effect.

Analgesics↗
PubMed2001

Diagnosis of deep vein thrombosis using platelet scintigraphy.

PURPOSE: We reviewed the usefulness of platelet scintigraphy, in which autologous platelets labeled with indium-111-oxine reveal thrombotic activity, for evaluating deep vein thrombosis (DVT). MATERIALS: During the past 2 years, 39 cases with DVT were enrolled in this study. DVT was definitely diagnosed by color duplex scanning, platelet scintigraphy or both in all cases. For semiquantitative analysis, we estimated the ratio of accumulation in the abnormal region to that in the normal vein on the other side, and defined an abnormal accumulation ratio as over 1.2. RESULTS: Abnormal accumulation ratio showing active DVT was recognized in 30 cases (77%), and showed a good correlation with clinical symptoms. In addition, in 19 cases with crural DVT, platelet scintigraphy showed abnormal accumulation ratio in 16 cases (84%), while duplex scanning detected thrombi in 13 cases (68%). In cases with abnormal accumulation ratio, thrombolytic and anticoagulant therapy were very effective for improving clinical symptoms as well inducing regression of the accumulation ratio. CONCLUSIONS: Platelet scintigraphy was very useful for the diagnosis and treatment of DVT and for evaluation of the effect of anticoagulant therapy. Limitations in the definite diagnosis of deep vein thrombosis (DVT) have been apparent for more than three decades. During the last decade, duplex scanning has reached a high level of accuracy and has been considered the gold standard in the diagnosis of DVT, instead of venography. However, duplex scanning and venography demonstrates only the anatomic alterations associated with venous lesions. In contrast, in platelet scintigraphy, the labeled platelets are incorporated directly into the thrombus and can reveal thrombus activity. We noticed that autologous platelets labeled with indium-111-oxine accumulated on fresh lesions of DVT. This observation suggested two applications of this technique: 1) evaluation of the role of platelets in the pathophysiologic characteristics of DVT; and 2) monitoring the effects of anticoagulant therapy.

Adult↗
PubMed2001

Right atrial myxoma associated with atrial septal defect: a case report and review of the literature.

We describe a case of right atrial myxoma with mild cyanosis due to a right-to-left shunt at the atrial level. The patient was a 31-year-old woman with a 10-month history of easy fatigability and shortness of breath. Echocardiography showed a right atrial tumor producing a partial dynamic tricuspid obstruction. Digital subtraction angiography via the superior vena cava disclosed a mass lesion which occupied the right atrium with early visualization of the ascending aorta. Successful excision of the tumor and repair of the atrial septal defect totally relieved her presenting symptoms. In a rare association of a right atrial myxoma with atrial septal defect, preoperative evaluation and operative management are discussed.

Adult↗