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Biomedical subjects

I Ikeda

Publications and source records attributed to I Ikeda.

At least 91 records · Page 5Linked to original sources
PubMed1995

[Stereotactic radiosurgery using a linear accelerator (LINAC): simulation and positioning].

Stereotactic radiosurgery using a Gamma unit obtains good results for small intracranial diseases, arteriovenous malformation (AVM) and acoustic neurinoma. In stereotactic radiosurgery using a linear accelerator (LINAC), many fundamental problems are to be solved. 1) accuracy of a LINAC, 2) making the collimators for high energy X-ray narrow beams, 3) dosimetry for high energy X-ray narrow beams, 4) irradiation methods for stereotactic radiosurgery, 5) fixation of a patient's head and 6) simulation of a target. The usefulness of our method for simulation of a target and for positioning for radiosurgery was investigated. High energy X-ray narrow beams obtained with the collimators for narrow beams (field sizes: 9mm phi, 18mm phi and 27mm phi) satisfy clinical requirements for stereotactic radiosurgery, as indicated by dose profiles and isodose curves. No dosimetry method for high energy X-ray narrow beams has been established yet. Of the main irradiation methods for stereotactic radiosurgery, the method using multiple non-coplanar converging arcs needs no drastic reconstruction for use with LINAC. A patient's head was completely fixed by the stereotactic frame (Patil stereotaxic system or Leksell micro-stereotactic system). Simulation of a target was performed under CT scan. On CT image, the center of a target was determined and the three-dimensional coodinate on the stereotactic head frame target was settled so that the target would be reached. The three-dimensional coordinate for the target was coincided with the isocenter of a LINA by the laser beams of three-directional pointers. Afterwards, the target position was finely adjusted, by using the target positioner manipulator system.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMed1995

Case of vesico-appendiceal fistula secondary to mucinous adenocarcinoma of the appendix.

We present a rare case of vesico-appendiceal fistula secondary to mucinous adenocarcinoma of the appendix. Transurethral biopsy of the bladder revealed a mucinous adenocarcinoma of probable colonic origin. Adenocarcinoma of the appendix that directly invaded the bladder was diagnosed preoperatively by air-contrast barium enema, colonoscopy and magnetic resonance imaging. When one encounters a case of adenocarcinoma of the bladder suspected to be of colonic origin, one should examine the colon and rectum as well as the appendix and cecum.

Adenocarcinoma, Mucinous↗
PubMed1994

Selective phototoxic destruction of rat Merkel cells abolishes responses of slowly adapting type I mechanoreceptor units.

1. The fluorescent dye quinacrine which accumulates in Merkel cells in touch domes was administered to rats and the effects of excitation light irradiation on the mechanical responses of slowly adapting (SA) type I units innervating the touch domes were investigated. 2. Histological examination showed that after 10 min of irradiation degeneration was specifically localized to Merkel cells loaded with quinacrine. Nerve terminals associated with Merkel cells remained intact, even after treatment. 3. In SA type I units, responses to standard stimulation (a 100 ms ramp followed by a 2.9 s plateau of 400 microns constant displacement) decreased significantly after irradiation of the domes with quinacrine-excitation light through a 'B' filter ('B' light). With 5 min irradiation, the response decreased to 52 +/- 7% (n = 10, mean +/- S.E.M.) of the pretreated value, to 17 +/- 4% with a 10 min treatment and practically disappeared within 20 min. 4. In SA type I units with non-loaded Merkel cells, the response increased to 119 +/- 8% (n = 13) with 5 min irradiation and was 99 +/- 9% with the 10 min treatment. At around 15 min after the onset of irradiation there was a gradual decrease and within 60 min the response disappeared. 5. When responses were divided into phasic (0-120 ms after the onset of stimulation) and tonic (120-3000 ms) components, 'tonic' responses were more affected than 'phasic' ones in quinacrine-loaded SA type I units. 6. Stimulus-response curves shifted to the right and downwards in SA type I units with quinacrine-loaded Merkel cells after irradiation, but no significant change was seen in SA type I units without quinacrine. 7. Our observations are consistent with the hypothesis that Merkel cells are responsible for mechanoelectric transduction in SA type I units.

Animals↗
PubMed1994

Influence of Korean pine (Pinus koraiensis)-seed oil containing cis-5,cis-9,cis-12-octadecatrienoic acid on polyunsaturated fatty acid metabolism, eicosanoid production and blood pressure of rats.

The effects of dietary Korean pine (Pinus koraiensis)-seed oil containing a peculiar trienoic acid (cis-5,cis-9,cis-12-18:3, pinolenic acid, approximately 18%) on various lipid variables were compared in rats with those of flaxseed (Linum usitatissimum L.) oil, safflower (Carthamus tinctorius L.) oil and evening primrose (Oenothera biennis L.) oil under experimental conditions where the effects of different polyunsaturated fatty acids could be estimated. In Sprague-Dawley rats fed on diets containing 100 g fat and 5 g cholesterol/kg, the hypocholesterolaemic activity of pinolenic acid was intermediate between alpha-linolenic and linoleic acids. Analysis of the fatty acid composition of liver phosphatidylcholine indicated that, in contrast to alpha-linolenic acid, pinolenic acid does not interfere with the desaturation of linoleic acid to arachidonic acid. However, the effects on ADP-induced platelet aggregation and aortic prostacyclin production were comparable. When spontaneously hypertensive rats were fed on diets containing 100 g fat/kg but free of cholesterol, gamma-linolenic and pinolenic acids, as compared with linoleic acid, increased prostacyclin production and tended to reduce platelet aggregation. In addition, pinolenic acid attenuated the elevation of blood pressure after 5 weeks of feeding. Thus, the results of the present studies indicate the beneficial effects of pinolenic acid on various lipid variables.

Animals↗
PubMed1994

alpha-Linolenic, eicosapentaenoic and docosahexaenoic acids affect lipid metabolism differently in rats.

Rats were fed purified diets containing 10% fat with constant (n-6):(n-3) polyunsaturated fatty acids [(n-6):(n-3); 2.3-2.6] and polyunsaturated:saturated fatty acids (1) ratios. This was obtained with alpha-linolenic acid, eicosapentaenoic acid and docosahexaenoic acid added at 1 g/100 g diet. Eicosapentaenoic acid and docosahexaenoic acid were added as the ethyl esters. The concentration of plasma cholesterol in rats fed docosahexaenoic acid was significantly lower than in those fed alpha-linolenic acid. The concentration of plasma triglyceride was significantly lower in rats fed eicosapentaenoic acid than in those fed docosahexaenoic acid. Docosahexaenoic acid significantly reduced hepatic cholesterol compared with alpha-linolenic acid and eicosapentaenoic acid. Both eicosapentaenoic acid and docosahexaenoic acid decreased hepatic triglyceride compared with alpha-linolenic acid, but this effect was more pronounced in the docosahexaenoic acid group. There was no significant difference in fecal excretion of neutral and acidic steroids and apparent fat absorption. In rats fed docosahexaenoic acid, the proportion of arachidonic acid in liver microsomal phosphatidylcholine was lower than in those fed eicosapentaenoic acid. The same tendency was observed in plasma, platelet and aortic phosphatidylcholine and liver microsomal phosphatidylethanolamine and phosphatidylinositol. Dietary docosahexaenoic acid, but not eicosapentaenoic acid, significantly decreased aortic production of prostacyclin compared to alpha-linolenic acid, whereas platelet aggregation by collagen was not affected by the difference in dietary (n-3) polyunsaturated fatty acids.

Animals↗
PubMed1994

Lymphatic transport of stearic acid and its effect on cholesterol transport in rats.

Lymphatic transport of stearic acid, given as completely hydrogenated rapeseed oil (R10), 9 to 1 (R9) and 5 to 5 (R5) mixtures of R10, and soybean oil and completely hydrogenated tallow (T) was examined in the rat cannulated thoracic duct. R10, R9, R5, and T contained 91.4, 81.5, 46.5, and 63.6% stearic acid, respectively. A large portion of the remaining fatty acids in T was palmitic acid (31%). These fats were emulsified with bile salt and albumin, and administered via a stomach tube. Lymphatic recovery of stearic acid at 24 h was lowest in R10 and highest in R5, and intermediate in R9 and T. Recovery of oleic and linoleic acids in rats given R5 was almost complete and significantly higher than that of stearic acid. When T was given, the 24 h recovery of stearic acid was significantly lower than that of palmitic acid. A highly inverse correlation between the recovery and the content of stearic acid in administered fats was observed in R10, R9, and R5. Lymphatic recovery of cholesterol was almost parallel with that of stearic acid. Although the content of stearic acid in T was lower than that in R9, the recovery of stearic acid and cholesterol was almost similar. The results indicate that the rate of lymphatic recovery of stearic acid is affected by the quantity and quality of coexisting fatty acids.

Absorption↗
PubMed1994

Effects of dietary short-necked clam, Tapes japonica, on serum and liver cholesterol levels in mice.

Male mice were fed cholesterol-supplemented diets containing short-necked clams or defatted short-necked clams for 2 weeks under the dietary regimen of the same dietary level of protein (20%), fat (5%), and cholesterol (0.5%). Casein was used as a control protein. Similar results were obtained in two separate experiments with either boiled (Exp. 1) or steamed (Exp. 2) short-necked clams. The concentration of serum cholesterol in mice fed a clam diet was lower than in those fed control and defatted clam diets. Delipidation of clam raised the concentration of serum triglyceride. Both clams and defatted clams markedly reduced the concentration of hepatic cholesterol. Fecal excretion of neutral steroids was significantly increased by clam but not defatted clam, whereas the excretion of acidic steroids was stimulated by both specimens, in particular defatted clam. The results suggest that the hypocholesterolemic effect of short-necked clams is attributed to its lipid fraction, whereas non-lipid components contribute to the reduction of hepatic cholesterol and increased fecal excretion of bile acids.

Animals↗
PubMed1994

[A case of malignant pheochromocytoma with high levels of serum neuron-specific enolase (NSE) and calcitonin].

A 71-year-old woman was admitted with the chief complaint of headache, lumbago and slight fever. Computerized tomographic (CT) scan demonstrated a large soft tissue mass with multiple cystic necrosis in the right adrenal region. The plasma norepinephrine concentration was excessive and serum levels of neuron-specific enolase (NSE), calcitonin and parathormone were elevated. MIBG scintigraphy showed a high uptake in the same region. Under the diagnosis of pheochromocytoma without distant metastasis, right adrenalectomy was performed. The tumor was removed en bloc with right kidney and a part of the liver because of inflammatory adhesion. The histological examination revealed benign pheochromocytoma. After the operation, norepinephrine and calcitonin decreased to normal but the levels of NSE and PTH remained high. One year after operation, chest X-ray revealed multiple lung metastases and after 1.5 years she died of respiratory failure. Autopsy revealed multiple lung and bone metastases and a liver metastasis, parathyroid glands showed hyperplasia but the thyroid gland showed no abnormal change. This clinical course suggests that serum NSE might be a useful tumor marker for differentiating malignant pheochromocytoma from benign one, and this tumor producing calcitonin caused secondary hyperparathyroidism.

Adrenal Gland Neoplasms↗
PubMed1994

[A case of primary signet ring cell carcinoma of urinary bladder].

A 72-year-old female patient presented to our clinic with the chief complaint of gross hematuria and urinary frequency on September 6, 1990. Cystoscopic examination revealed a thumb's head size nonpapillary tumor. The tumor was located adjacent to the orifice of the left ureter. Histological findings of the tumor by transurethral resection (TUR) indicated transitional cell carcinoma with partial signet ring cell carcinoma. No other malignant findings in any other organs including the gastrointestinal tract were noted. Total cystectomy was performed and Indiana pouch was constructed. Histopathological staging was pT1 N0 M0. The patient died of multiple metastasis of the signet ring cell carcinoma on June 22, 1992. This is the thirty-second case of signet ring cell carcinoma of urinary bladder reported in the medical literature in Japan. We investigated 19 alive or unknown cases as follow up and briefly discussed the treatment and outcome of the primary signet ring cell carcinoma of the urinary bladder. The outcome appeared to be somewhat better than previous reports. Total cystectomies were performed in 18 of the 32 cases (56.3%). As noted in past reports, the treatment of our patient consisted of total cystectomy. Twenty-two patients died of signet ring cell carcinoma. Recurrence to the pelvic area was observed in 18 of the 22 (81.8%) patients who died. Because of this high rate of recurrence, we recommend a thorough assessment of the pelvic area of the patients diagnosed with signet ring cell carcinoma of urinary bladder.

Aged↗
PubMed1994

[Recent advances in immunological diagnosis for tuberculosis].

Recent advances in immunological diagnosis for tuberculosis including tuberculin Mantoux test and serodiagnosis were reviewed. New tuberculins (T1327, T1456) were reported to be more specific than the conventional one (RT23). Tuberculins from atypical mycobacteria (PPD-B, PPD-Y, PPD-F) were reported as a useful tool for the diagnosis of atypical mycobacteriosis. Optical density index method is a most appropriate method for a clinical use among several methods for the expression of antigen titer in serodiagnosis using ELISA. The duration of disease is important for understanding the results. IgM antibody rises in the early stage of the disease and comes down in 10 weeks after onset, while IgG antibody rises lately. Anti-cord factor antibody is a highly specific antibody for tuberculosis and may be a potent candidate for a clinical diagnostic tool. Anti-PPD-B antibody was elevated in atypical mycobacteriosis and pulmonary tuberculosis also. The ratio of anti-PPD-B antibody to anti-PPDs antibody was elevated in atypical mycobacteriosis while it was lowered in pulmonary tuberculosis. It may be helpful for suggesting the causative organism when the sputum smear is positive. The opposite results have been reported on the serodiagnosis in HIV infection. The usefulness of serodiagnosis for tuberculosis in HIV infected patients remained controversial.

Antibodies, Bacterial↗
PubMed1994

[A clinical study on lymph node metastasis of renal pelvic and ureteral cancers].

A clinical study was performed on 38 patients with renal pelvic and ureteral cancers who were treated in our hospital between 1977 and 1992. Nine patients (23.7%) had lymph node metastasis. The risk factors of lymph node metastasis were high grade, high stage and class IV or V or urine cytology. None of the patients with G1 or under pT1 had lymph node metastasis. The 5-year survival rate of the patients without [lymph node metastasis was 76.7% and that of the patients with lymph node metastasis was 11.1%. Although 6 of the 9 patients with G1 or G2 and under pT1 did not have adjuvant therapy, none of them died of the cancer. We concluded that lymph node metastasis in renal pelvic and ureteral cancers was the most important prognostic factor and that regional lymphadenectomy might be useful for the decision of adjuvant therapy.

Adult↗
PubMed1993

Lymphatic transport of eicosapentaenoic and docosahexaenoic acids as triglyceride, ethyl ester and free acid, and their effect on cholesterol transport in rats.

Lymphatic transport of docosahexaenoic (DHA) and eicosapentaenoic (EPA) acids given in the forms of triglyceride, ethyl ester of free acid and their effect on cholesterol transport was compared in lymph-cannulated rats. Lymphatic recovery of DHA and EPA given by stomach tube in the form of triglyceride in which they were mainly located at the 2-position was significantly higher than that of the ethyl ester or free acid during the first 6 hr after the administration and the tendency continued until 9 hr. In contrast, the 9 to 24 hr recovery of DHA and EPA in the forms of ethyl ester and free acid was considerably higher than that of triglyceride. Consequently, cumulative 24 hr recovery of EPA was comparable among the three forms. However, the 24 hr recovery of DHA was highest in free acid, lowest in ethyl ester and intermediate in triglyceride. Recovery of the free acid between 9 and 24 hr after administration was significantly higher than that given in the forms of triglyceride or ethyl ester. Cholesterol recovery in lymph of rats given with ethyl ester or free acid was lower than that given with triglyceride at an early stage after the administration in both EPA and DHA. Cumulative 24 hr recovery of cholesterol in rats given these fatty acids as ethyl ester was significantly lower than in those given as the other two forms.

Animals↗
PubMed1993

[New salvage chemotherapy (cisplatin, adriamycin, bleomycin, methotrexate, etoposide) for advanced nonseminomatous testicular cancer: experience in three cases].

Three patients with advanced non-seminomatous testicular tumor were treated with a new salvage chemotherapy. All patients were refractory to prior PVB (cisplatinum, vinblastine, bleomycin) or VAB-6 (cisplatinum, bleomycin, vinblastine, dactinomycin, cyclophosphamide) therapy. They were treated with the following combination chemotherapy: Cisplatin 30 mg/body day 1-5; adriamycin 40 mg/body day 1; bleomycin 30 mg/body/day 1: methotrexate 400 mg/body day 1; etoposide 150 mg/body day 1-5 (CABME therapy). This treatment was repeated monthly and in total four courses were given. One complete response and one partial response were obtained. Especially, we achieved 65% and 63% remission of liver metastases and residual tumors could be resected. Myelosuppression was marked, but other toxicity was tolerable. Therefore, we postulated that CABME therapy played an important role for the refractory testicular tumors.

Adult↗
PubMed1993

[Usefulness anti-PPD antibody in the medical practice of tuberculosis].

The decline rate of tuberculosis has decreased recently in Japan. One of the problems is the tendency of increasing doctor's delay in the diagnosis of tuberculosis. One of measures against this problem is to develop a new laboratory diagnostic method. We studied anti-PPD (Purified Protein Derivative of tuberculin) antibody in serum, pleural effusion, and bronchoalveolar lavage fluid (BAL), and found its clinical usefulness in the medical practice of tuberculosis. Firstly the methods of enzyme linked immunosorbent assay (ELISA) for the antibody to PPD were examined. The expression of antibody titer in optical density was found to be the most accurate and most simple method, and was applied in this study. IgG, IgM and IgA antibody to PPD were measured in serum, BAL and pleural effusion obtained from 122 patients with pulmonary tuberculosis, 54 patients with tuberculous pleurisy, 39 patients with lung cancer, 39 patients with malignant pleurisy, 37 patients with pneumonia, 26 patients with chronic bronchitis, 51 patients with sarcoidosis, or 49 control subjects. Serum level of IgG, IgM, and IgA antibody to PPD was elevated in tuberculosis compared with those in other diseases or control subjects. The difference was most distinctive in IgG antibody. Serum IgG antibody was higher in chronic case than in acute case and IgM antibody was higher in acute case than in chronic case. IgG, IgM and IgA antibody in pleural effusion was elevated in tuberculous pleurisy compared with those in malignant pleurisy. IgG antibody was higher in chronic tuberculous pleurisy than in acute tuberculous pleurisy and IgM antibody was higher in acute pleurisy than in chronic one.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Bacterial↗
PubMed1993

[Clinical study of 22 cases of torsion of the spermatic cord].

We performed surgical treatment in 22 cases of torsion of the spermatic cord during the past sixteen years. Orchiopexy was performed in 9 cases, but in 13 cases orchiectomy was unavoidable. For five patients the visit to a doctor was too late. In five other cases a mistaken diagnosis was made by local medical doctors. Improvement of the success rate of orchiopexy requires that adolescents, their families and teachers should learn to recognize this disease, and doctors of other departments should recognize it as acute scrotum.

Adolescent↗
PubMed1993

[Idiopathic thrombocytopenic purpura (ITP) associated with renal injury: report of a case].

A 42-year-old woman with gross hematuria, left flank pain and vomit after being hit on her back admitted to our hospital. She has been under treatment for idiopathic thrombocytopenic purpura (ITP) with prednisolone for these last 14 years. Computerized tomographic (CT) scan revealed moderate laceration, subcapsular hematoma and perirenal hematoma of the left kidney. We tried treating her conservatively. The main treatment was absolute rest for two weeks, increase in the prednisolone dose and prevention from infection. On the 3rd day, the platelet count dropped to 4,000/mm3, but transfusion of platelets was not done to provide for emergency. The platelet count increased gradually and returned to normal on the 8th day. We decreased the prednisolone dose according to the platelet count. After 5 weeks, microscopic hematuria disappeared. Her clinical course was uneventful and she was discharged after 7 weeks.

Accidental Falls↗
PubMed1992

Tea catechins decrease micellar solubility and intestinal absorption of cholesterol in rats.

A(-)-epicatechin (EC) and (-)-epigallocatechin (EGC) mixture and a mixture of their gallates (ECG and EGCG, respectively) markedly lowered lymphatic cholesterol absorption in rats with a cannulated thoracic duct. A mixture of ECG and EGCG was more effective in reducing cholesterol absorption than the EC and EGC mixture. These catechins also tended to decrease lymphatic absorption of triacylglycerols, although not so pronounced as in cholesterol absorption. An in vitro study on micellar solubility of cholesterol showed that these catechin mixtures precipitated cholesterol solubilized in mixed bile salt micelles in a dose-dependent manner. A mixture of ECG and EGCG more effectively precipitated micellar cholesterol than a mixture of EC and EGC. When purified EC, EGC, ECG and EGCG were used, EGCG was more effective in precipitating micellar cholesterol than ECG. The effect of EC and EGC was comparable and weaker than their gallate esters. The bile acid concentration in the micelles was not affected by these catechins. A positive correlation was observed between the amount of coprecipitated EGCG and cholesterol. These results clearly show that tea catechins, in particular their gallate esters, effectively reduce cholesterol absorption from the intestine by reducing solubility of cholesterol in mixed micelles. The observation accounts for the hypocholesterolemic effect of tea catechins.

Animals↗