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Biomedical subjects

M Ohkawa

Publications and source records attributed to M Ohkawa.

At least 109 records · Page 6Linked to original sources
PubMed1996

Cerebral vasospastic vessels: histologic changes after percutaneous transluminal angioplasty.

PURPOSE: To investigate histologic changes before and after percutaneous transluminal angioplasty (PTA) in experimental cerebral vasospasm in comparison with normal vessels. MATERIALS AND METHODS: In seven monkeys, vasospasm was induced in the subarachnoid space. After 7 days, PTA was performed. Microscopic studies were performed in vasospastic vessels. In two animals, vasospasm was induced but angioplasty was not performed. The controls were two animals without vasospasm who underwent only contralateral angioplasty. RESULTS: Angiography after vasospasm revealed marked narrowing but dilatation after PTA, without changes in distal spastic vessels. Specimens after PTA showed platelets that covered denuded endothelium, stretching, and focal dehiscence of internal elastic lamina and altered myocytes in media. Myocytes were deformed and arranged irregularly. These changes were not uniform. CONCLUSION: The prolonged effect of PTA may be caused by mechanical damage of myocytes and the nonuniformity of histologic changes in vascular walls.

Angioplasty, Balloon↗
PubMed1996

Alleviation of cisplatin nephrotoxicity: efficacy of local intra-arterial injection concomitant with hemodialysis.

Although cis-diamminedichloroplatinum (cisplatin) is widely used in the treatment of malignant tumors, the dose administered is limited because of side effects such as nephrotoxicity. The plasma levels of non-protein-bound platinum, which can be removed by dialysis, play an important role in the antitumor effects and the appearance of side effects. Selective intra-arterial injection of cisplatin during concomitant hemodialysis (HD) was performed in patients with gynecological malignancies. At a dose of 100 mg, about three times the non-protein-bound platinum excreted in the urine during the same period was removed by HD. The area under the time-concentration curve of plasma total platinum up to 5 h after intra-arterial injection was reduced by 46%. When doses of 200 or 250 mg were administered concomitantly with HD, the maximum plasma levels were suppressed to about the same degree as when 100 mg were injected without concomitant HD. A definite reduction in the incidence of side effects was seen, and a reduction in the severity of nephrotoxicity was also observed when 100 mg were given with HD. No severe side effects were found even when 200 or 250 mg were administered with concomitant HD. The antitumor effects were not reduced or possibly potentiated, but follow-up is still of short duration. These results indicate that chemotherapy with local intra-arterial injections of cisplatin using concomitant HD not only reduces systemic side effects, in particular nephrotoxicity, but also allows for increased doses at the tumor site and can be applied in patients with renal dysfunction.

Acetylglucosamine↗
PubMed1996

Melanotic neuroectodermal tumor of infancy in the epididymis. Case report and literature review.

We report a case of melanotic neuroectodermal tumor that originated in the right epididymis of a 4-month-old Japanese male and review reports of similar cases. Since we could not exclude malignant disease preoperatively, we performed a radical orchiectomy. Histopathological and immunohistochemical studies revealed features characteristic of a melanotic neuroectodermal tumor. Imaging studies showed no distant metastases.

Epididymis↗
PubMed1996

Morphological and functional factors predicting bladder deterioration after spinal cord injury.

PURPOSE: We investigated factors predictive of morphological and functional deterioration of the bladder in patients with spinal cord injury. MATERIALS AND METHODS: Urological evaluation, including excretory urography and urodynamic studies, was performed once a year in 66 patients. Bladder compliance was used as an index of bladder function. RESULTS: Mean age of the patients with worsening bladder form and function was significantly greater than that of those with no change. In patients with worsening bladder function intermittent catheterization was performed less frequently and mean catheterization volume was greater compared to those with improvement and no change. Catheterization was less frequent and at long intervals in patients with a high urethral closure pressure. CONCLUSIONS: High storage pressure due to a high urethral closure pressure is believed to cause deterioration of bladder form and function.

Adult↗
PubMed1996

Urodynamic effects of intravesical oxybutynin chloride in conscious rats.

PURPOSE: To examine the factors of intravesical oxybutynin influencing the cystometrogram in normal conscious rats at various pH levels and concentrations of oxybutynin. MATERIALS AND METHODS: A cystostomy catheter was implanted into the bladders of male Sprague-Dawley rats. We compared the urodynamic effects of intravesical oxybutynin dissolved in pH 4.44, 6.44 and 8.44 buffer. Two concentrations of oxybutynin solution were adopted, 0.06 and 0.6 mg./ml., and were dissolved in each pH buffer. RESULTS: Although a 26% increase in bladder capacity was recognized 1 hour after instillation of pH 8.44, 0.06 mg./ml. oxybutynin, no significant difference was found in comparison with control rats. At the concentration of 0.6 mg./ml., bladder capacity markedly decreased 30 minutes to 1 hour after instillation even at pH 6.44 and 8.44. Significant decreases in detrusor contraction pressure were recognized 30 minutes to 1 hour after instillation. However, there were no significant differences among the 3 pH oxybutynin solutions. Compared with preinstillation values, significant increases in residual urine rates were observed in all pH oxybutynin solutions. Furthermore, the residual urine rate after instillation of pH 8.44 oxybutynin solution differed significantly from that of pH 4.44 oxybutynin. CONCLUSION: Our results demonstrate that pH and concentration of intravesical oxybutynin solution may play an important role in relaxation of the bladder. A high concentration of oxybutynin is considered irritating to the bladder mucosa.

Administration, Intravesical↗
PubMed1996

Endoscopic treatment of vesicoureteral reflux in patients with myelodysplasia.

PURPOSE: We assessed the usefulness of and indications for endoscopic treatment of vesicoureteral reflux in myelodysplasia patients. MATERIALS AND METHODS: A total of 26 patients treated with intermittent catheterization was divided into 11 (16 ureters) with and 15 without vesicoureteral reflux. In 9 patients (13 ureters) endoscopic correction was performed with 3% atelo-collagen and without anesthesia at the outpatient clinic. In each ureter we obtained the sum of scores for 4 risk factors for upper urinary tract deterioration: bladder compliance less than 10 ml./cm. water, grade 2 to 3 bladder deformity, detrusor-sphincter dyssynergia and urethral closure pressure 50 cm. water or greater. RESULTS: No reflux was demonstrated immediately after the initial collagen injection but cystography 3 to 6 months later showed recurrent reflux in 5 ureters (38%). Repeat injection cured the reflux, with results persisting for an average of 17 months. Mean risk factor score for patients without vesicoureteral reflux was significantly lower than that for patients with reflux. In patients treated with intermittent catheterization and anticholinergic agents the mean score for ureters with an increased or unchanged reflux grade was significantly greater than for those with a decreased grade. CONCLUSIONS: Endoscopic treatment of reflux appears to be safe and useful in patients with myelodysplasia. The treatment is preferable in those with high risk factor scores due to the possibility of increased reflux grade in such patients.

Animals↗
PubMed1996

[Treatment and prognosis of renal cell carcinoma extending into the inferior vena cava].

Out of 173 patients with renal cell carcinoma diagnosed at our department between January 1984 and December 1994, 9 (5.2%) had an inferior vena caval tumor thrombus. They consisted of 6 men and 3 women between 43 and 74 years old with a mean age of 59.8 years. The tumors were on the right and left sides in 5 and 4 patients, respectively. According to the Novick's classification, 2, 1, 4 and 2 patients had level 1 (perirenal), level 2 (infrahepatic), level 3 (intrahepatic) and level 4 (suprahepatic) tumors, respectively. Five patients without distant metastases underwent nephrectomy and removal of the vena caval tumor thrombus. Although renal tumors and vena caval tumor thrombi were completely resected in all of the 5, 4 died of disease within 3 years. Only 1 patient without tumor invasion into the inferior vena caval wall survived over 5 years without disease. Since surgical treatment is the sole radical method for renal cell carcinoma, surgery is recommended for the patients even with a vena caval tumor thrombus unless there are metastases.

Adult↗
PubMed1996

[Portal embolization using lipiodol-gelatin sponge].

Gelatin sponge moistened with lipiodol was prepared for use in portal embolization to improve percutaneous transhepatic portal embolization as preoperative management of patients undergoing extensive liver resection. For one sheet of gelatin sponge (20 x 60 x 7mm)0.5ml of lipiodol was used. Five sheets cut to 2mm square pieces and mixed with physiological saline solution were injected into the right portal vein. This embolic material proved safer and more reliable than gelatin sponge mixed with water-soluble contrast medium, because it provided sufficient opacification to grasp the extent of embolization and prevented back flow.

Embolization, Therapeutic↗
PubMed1996

[Comparative evaluation of 99mTc-MIBI (hexakis2-methoxy isobutyl isonitrile) and 201Tl-chloride in primary lung cancer].

We performed comparative study, using 99mTc-MIBI and 201Tl-chloride in patients with primary lung cancer. There were 42 patients with primary lung cancer. All patients underwent dual radionuclide imaging with 201Tl-chloride and 99mTc-MIBI. Regions of interest were placed over the tumor area (T) and contralateral normal lung area (N). A tumor to normal lung ratio (T/N ratio) and retention index were calculated by early and delayed ratios. In the SPECT images, the positive rate was 98% in both the early and delayed images for 201Tl-chloride and 95% in the early and 88% in the delayed images for 99mTc-MIBI. Both early and delayed T/N ratios of 201Tl-chloride were significantly higher than those of 99mTc-MIBI. The retention index of 201Tl-chloride was higher than that of 99mTc-MIBI. T/N ratio and retention index did not significantly correlated with reference to histological types. We conclude that 99mTc-MIBI SPECT can be helpful in localizing primary lung cancers. However, in our study the tumor accumulation of 99mTc-MIBI was significantly lower compared with 201Tl-chloride.

Adult↗
PubMed1996

[Squamous cell carcinoma of the renal pelvis associated with renal stones in a patient with chronic renal failure: a case report and a review of the Japanese literature].

A case of squamous cell carcinoma of the left renal pelvis associated with chronic renal failure on hemodialysis is reported. The patient, a 59-year-old man, had undergone bilateral nephrolithotomy, in 1966, followed by right ureterolithotomy and bilateral percutaneous nephrolithotripsy, but residual stones existed. He suffered from left flak pain and fever, and computed tomography (CT) and magnetic resonance imaging (MRI) revealed left perirenal abscess in July 1994. Percutaneous drainage and antibacterial chemotherapy were performed, but his symptoms did not improve. Three months later, CT and MRI revealed a mass in the left perirenal space and destruction of the 12th thoracic vertebra, which were considered to be infectious changes. On November 9, 1994, left nephrectomy was performed. Histopathological diagnosis was moderately differentiated squamous cell carcinoma, grade 2, INF-gamma, pT4, pR1, pL0 and pV1. In spite of irradiation therapy, he died on January 19, 1995.

Carcinoma, Squamous Cell↗
PubMed1996

[Second phase 99mTc-HMDP accumulation using three phase bone scintigraphy in a case of primary breast cancer].

Accumulation of 99mTc-HMDP was recognized by three-phase bone scintigraphy in a case of primary breast cancer. A 67-year-old female was found to have a 14 x 13 mm mass in the upper lateral area of the left breast. At operation the histopathological finding was a proven solid-tubular carcinoma. On the first phase images, there was no abnormal accumulation in the tumor. On the second phase images, there was abnormal accumulation in the tumor, however, abnormal accumulation was observed followed by a decrease in accumulation. The third phase image showed no abnormal extra-skeletal accumulation. Color Doppler ultrasound sonography showed an abundance of color signals within the breast tumor. Increased 99mTc-HMDP accumulation in the second phase image might reflect tumor hypervascularization. It is concluded that three-phase bone scintigraphy using 99mTc-HMDP has the ability of positive description in primary breast cancer.

Adenocarcinoma↗
PubMed1996

[Evaluation of 99mTc-MIBI to predict chemotherapeutic response in patients with small cell lung carcinoma].

The purpose of this study was to evaluate the relationship between 99mTc-MIBI (MIBI) accumulation and the response to chemotherapy. Twelve patients with small cell lung carcinoma (SCLC) underwent MIBI SPECT before chemotherapy. SPECT data were acquired 15 minutes and 2 hours after the injection of 600MBq MIBI. The early ratio (ER), delayed ratio (DR) and retention index (RI) was measured. Tumor response were classified into complete remission (CR), partial remission (PR) and no change (NC) by follow-up CT examination. The mean +/- standard deviation of ER was 3.10 +/- 0.85 (n = 4) for CR, 2.72 +/- 0.46 (n = 5) for PR and 2.43 +/- 0.95 (n = 3) for NC. DR was 3.05 +/- 1.11 for CR, 2.64 +/- 0.30 for PR and 1.90 +/- 0.82 for NC. RI was -3.0 +/- 11.69 for CR, -1.84 +/- 11.03 for PR and -18.19 +/- 38.51 for NC. CR, DR and RI were not significantly correlated with tumor response (CR, PR, NC) MIBI has the potential to predict the response to chemotherapy in SCLC.

Adult↗
PubMed1995

Cerebellar diaschisis in pontine infarctions: a report of five cases.

We evaluate regional cerebral and cerebellar perfusion to prove the occurrence and follow the persistence of crossed cerebellar diaschisis in infratentorial pontine infarction. Six consecutive patients exhibiting mild hemiparetic symptoms or a heavy feeling in the head (mean age 65 years; four women, two men) and diagnosed as having pontine infarction by magnetic resonance imaging were subjected to evaluation. Lesions due to infarction were located at the upper basis pontis in five patients and the upper tegmentum pontis in one, and medially at the paramedian portion in four and laterally in two. Regional cerebral and cerebellar perfusion was evaluated semiquantitatively by iodine-123 N-isopropyl-p-iodoamphetamine (IMP) single-photon emission tomography (SPET); this was done during the acute stage in five cases (mean time after onset: 0.7 months) and during the chronic stage in three (mean time after onset: 14.8 months). Four patients had two examinations during their clinical courses. For semiquantitative evaluation of perfusion, an asymmetry index was calculated for each region of interest, set symmetrically in regions of the cerebral cortex and cerebellum in both hemispheres. Significant asymmetry (P < 0.01) in cerebellar perfusion, which was reduced in the contralateral (n = 4) or ipsilateral (n = 1) cerebellar hemisphere, was demonstrated semiquantitatively in four cases during the acute stage and in one during the chronic stage, as compared with normal controls (n = 5, mean age 61 years). This asymmetry continued to the chronic stage (6.5 and 33.0 months) in two cases, while no patient showed any significant asymmetries in cerebral perfusion in any region of interest in either SPET study.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Intraoperative radiotherapy for gliomas.

Intraoperative radiotherapy (IORT) was performed in 20 of 36 patients with glioma; 11 glioblastomas, 7 malignant astrocytomas, 2 benign astrocytomas. Twenty or 25 Gy of irradiation was delivered in a single fraction intraoperatively, followed by external beam irradiation. The electron beam energy was selected so that the 80% isodose line fell at 2 or 3 cm below the residual tumor surface. Median survival time of IORT group was 14 months and that of the control group was 10 months. Difference of survival curve was significant. There were 6 incidences of complication caused by IORT; 1 radionecrosis, 1 convulsion, 1 abscess, and 3 severe brain edemas. IORT is suited for the treatment of malignant gliomas.

Adult↗
PubMed1995

D-arabinitol versus mannan antigen and candidal protein antigen as a serum marker for Candida pyelonephritis.

To evaluate serum markers for the diagnosis of Candida pyelonephritis, levels of D-arabinitol, candidal mannan antigen and candidal protein antigen were measured using an enzymatic fluorometric assay, an enzyme immunoassay and a latex agglutination assay, respectively. The study group comprised 36 patients with candiduria (11 disseminated candidiasis, 9 Candida pyelonephritis and 16 colonization) and 27 without candiduria. The D-arabinitol/creatinine ratio was the only marker that differentiated between Candida pyelonephritis and colonization (p < 0.01). Using the cut-off values (1.4 mumol/mg of D-arabinitol/creatinine ratio, 0.28 of mannan/creatinine ratio (x 10(4)) and 1:4 of protein antigen titer) D-arabinitol/creatinine ratio showed the highest sensitivity in Candida pyelonephritis (77.8%) as compared to mannan/creatinine ratio (55.6%) and protein antigen titer (11.1%) although there were no differences in specificity, positive predictive value or negative predictive value. These results suggest that D-arabinitol/creatinine ratio is the most useful marker of Candida pyelonephritis.

Aged↗
PubMed1995

Topical anaesthesia for bladder biopsies and cautery: intravesical lidocaine versus caudal anaesthesia.

A total of 62 patients were randomized to receive bladder biopsy and cautery with either topical lidocaine anaesthesia or caudal anaesthesia. The patients were asked to describe the level of pain experienced during the procedure on a scale from 0 (no pain) to 5 (unbearable pain). In 29 patients receiving topical lidocaine anaesthesia, the mean value was 1.6 at cold-cup biopsies and 2.7 at cautery, which were considered to be tolerable for the patients. On the other hand, in 33 patients who had biopsies and cautery with caudal anaesthesia, the mean values were 0.8 and 1.0, respectively, which were significantly lower than those in patients receiving topical anaesthesia (p < 0.01). Serum lidocaine levels were measured in 5 patients at 15 minutes from the beginning of biopsies, and were negligible. These results revealed that caudal anaesthesia provided more effective pain relief, although most patients could tolerate biopsy and cautery with topical lidocaine anaesthesia. The technique of topical anaesthesia is very simple and no side effects were observed. We thus conclude that topical lidocaine anaesthesia is useful and safe for bladder biopsies and cautery in most cases.

Administration, Intravesical↗
PubMed1995

Comparative clinical features of stage A1 and stage A2 prostate cancers. Is the concept of stage A changing from the current status?

We surveyed the comparative clinical features of patients with stage A1 and stage A2 prostate cancer. Preoperatively, prostate specific antigen (PSA) level was elevated in 50.0% of stage A2 patients as compared to 18.2% of stage A1 patients. Compared to low positivity of prostatic acid phosphatase in 12.5% of stage A2 and in 0% of stage A1, PSA was more sensitive to the presence of incidental carcinoma. During the observation period (mean 35.7 months) no stage A patient died of cancer. No evidence of the disease showed significantly higher rate, and death without cancer was significantly lower in stage A1.

Acid Phosphatase↗