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Biomedical subjects

R Yamada

Publications and source records attributed to R Yamada.

At least 145 records · Page 8Linked to original sources
PubMed1995

Effect of balloon occluded arterial infusion of anticancer drugs on the prognosis of cervical cancer treated with radiation therapy.

PURPOSE: The effect of local injection of anticancer drugs by balloon catheter, i.e., balloon occluded arterial infusion (BOAI), on the prognosis of cervical cancer treated with radiotherapy were retrospectively estimated. METHODS AND MATERIALS: Sixty-five patients with cervical cancer (Stage I-IV) treated by irradiation were included in the study. Among the 65 cases, 2 were in Stage I, 13 in Stage II, 40 in Stage III, and 10 in Stage IV. Patients who received surgical resection were excluded. Thirty-nine patients received BOAI and 44 received brachytherapy. Twenty-six patients were not indicated for BOAI because of insufficient renal function, hepatic complications, hematological complications, and refusal from the patients. Cisplatin (0.9-1.7 mg/kg), Adriamycin (0.7-0.9 mg/kg), and Pepleomycin (0.4-0.6 mg/kg) were administered simultaneously into the bilateral internal iliac arteries by BOAI. External irradiation was given by 10 MV x-ray. Total dose administered to the regional lymph nodes by the external irradiation was 48.3 +/- 8.7 Gy. Radium was used at brachytherapy. The dose delivered by the brachytherapy at point A was 45.3 +/- 14.9 Gy. Patients without brachytherapy received 26.1 +/- 19.1 Gy of boost irradiation by the external photon beam. The survival probabilities of the patients were calculated by Kaplan-Meier method. RESULTS: The 5-year survival rates of the Stage III patients with and without BOAI were 53 +/- 13% and 24 +/- 18%, respectively (p = 0.036). By multivariate analyses using Cox's proportional hazard model, stage and BOAI were selected as significant predictors of the prognosis. Transient bone marrow suppression was observed in about half of the patients with BOAI. No significant increase of the incidence of the late radiation damage by BOAI in rectum or in urinary bladder was observed. CONCLUSION: Balloon occluded arterial infusion of anticancer drugs may improve the prognosis of the patients with cervical cancer without increasing the incidence of the late radiation damage. A larger scale prospective randomized study is desired.

Actuarial Analysis↗
PubMed1995

Presence of free D-glutamate and D-aspartate in rat tissues.

The presence of free D-glutamate was demonstrated for the first time in rat liver, kidney and brain. This is based on the findings that the D-glutamate as well as D-aspartate in the tissue extracts co-chromatographed exactly with the authentic standards on HPLC, and that the treatment of the extracts with D-aspartate oxidase mostly abolished the HPLC peaks of these compounds. Contents of these acidic D-amino acids in the liver and kidney, as well as the percentages of D/(D + L), were lower in female than in male, while D-aspartate oxidase activities in the same tissues were inversely lower in male than in female, in agreement with a probable role of the enzyme. A significant correlation was observed between D-aspartate and D-glutamate contents in the liver, kidney and brain of individual animals, with the D-glutamate contents always higher than the D-aspartate contents.

Amino Acid Oxidoreductases↗
PubMed1995

Acute thrombolytic therapy and subsequent angioplasty for atherosclerotic stenosis of the basilar artery--case report.

A 50-year-old male presented with severe atherosclerotic stenosis of the basilar artery at its origin with very poor blood flow distally, manifesting as sudden onset of deterioration of consciousness to semicomatose with decerebrate posture. He regained consciousness dramatically after acute thrombolysis, although right hemiparesis persisted due to left pontine infarction. Follow-up angiography after 3 months of antiplatelet and anticoagulation therapy demonstrated severe residual stenosis of the basilar artery. Percutaneous transluminal angioplasty (PTA) resulted in wide patency of the basilar artery stenosis with excellent blood flow distally. Combination of acute thrombolytic therapy and subsequent PTA is an effective treatment for severe basilar artery occlusive disease.

Angioplasty, Balloon↗
PubMed1995

Usefulness of color Doppler flow imaging in differential diagnosis of multilocular cystic lesions of the kidney.

Color Doppler flow imaging was carried out in 10 multilocular cystic lesions of the kidney. These consisted of three renal cell carcinomas, three hemorrhagic renal cysts, one benign multilocular cystic nephroma, two infected renal cysts, and one benign multilocular renal cyst secondary to von Hippel-Lindau disease. In the patients with renal cell carcinoma, color signals were obtained at the septum and in the solid component within the lesions. A pulsatile wave with a large maximum flow velocity and a high PI value was obtained in two of them. In one of the patients with hemorrhagic renal cysts, color signals were obtained at the region of the septum. In the other benign lesions, however, color signals were obtained only at the peripheral margin, and the flow waveform in these cases was identical to the waveforms found in the interlobar arteries. This study suggested that color display in the lesion well reflects its vascularity in patients with multilocular cystic renal diseases and that measurement of the systolic maximum flow velocity by fast Fourier transform analysis is useful for the differential diagnosis of malignant versus benign lesions.

Adolescent↗
PubMed1995

Controversies in vascular imaging and intervention: a panel discussion.

PURPOSE: To express for educational purposes, different and often opposing views on controversial topics of current interest in vascular radiology. And to explore whether or not consensus can be reached on any of these controversial issues. METHOD: Panel discussion among experts in the field. With the help of a moderator, controversial topics were introduced for discussion. For each topic the moderator underscored the principal issue and asked relevant questions. All panelists were asked to express their views on all issues. The following issues were discussed: Atherectomy vs balloon angioplasty; Balloon angioplasty vs stents; Digital vs analog Imaging; TIPS as an emergency procedure; Regional thrombolysis; MRA vs conventional angiography; Laser angioplasty; Carbon dioxide angiography; Lymphangiography vs CT; The training of surgeons in angiography. The panelists were urged to avoid extensive references to the literature but rather to express their own personal opinions based on experience and practice. For each topic an attempt was made to arrive at consensus. RESULTS: Ten issues were presented for debate and discussion. Despite divergent opinions it was possible and relatively painless to reach consensus on seven controversies. On the remaining issues the panelists agreed to disagree. However even when there was disagreement certain trends became apparent. Local considerations and resource availability accounted for varied approaches to the solution of certain controversies. CONCLUSIONS: A panel discussion among experts may be a useful way to address controversies for educational purposes. Despite divergence of opinions consensus may be reached, or in absence of consensus general trends may become apparent.

Angioplasty, Balloon↗
PubMed1995

[Assessment of bone mineralization of hemodialyzed patients with SPA and DPA--different effect of PTX with the site].

We analyzed the bone changes at each site of secondary hyperparathyroidism (2 degrees HPT) on hemodialyzed patients using both single photon absorptiometry (SPA) and dual photon absorptiometry (DPA). The subjects were 35 hemodialysis patients (12 male, 24 female) with 2 degrees HPT. The bone mineral densities (BMD) of 1/3 radius, head, total body and 3rd lumbar spine were measured before and after parathyroidectomy (PTX). Before PTX, the BMD of 2 degrees HPT patients were lower than the normal range of all sites, especially at the radius which mainly consisted of cortical bone. After PTX, the BMD at all sites increased especially in the head. The BMD of the radius also continued to increased up two years after PTX, but it was not as increased as the BMD of head. The BMD of the lumbar spine which consisted of cancellous bone mainly increased after PTX for one year and decreased thereafter. This decrease was influenced by age. There was a difference with the site of BMD after PTX. The determination of changes of BMD of head and radius was considered useful for the judgment of treatment.

Absorptiometry, Photon↗
PubMed1995

[Alginate gel beads for chemoembolization: initial report].

Alginate gel beads (AGB) were studied as a new material for chemoembolization therapy. AGB were quickly produced by dripping a sodium alginate solution through a cannula into a calcium chloride solution, with bead size controlled by cannular size. AGB containing adriamycin or contrast medium were produced from the corresponding mixture. Sixty percent of adriamycin was eluted from AGB within one hour and 90% within 24 hours, while 95% of iopamidol was eluted in 30 minutes. AGB released these contents slower than gelatin sponge particles. Four dogs underwent transcatheter hepatic arterial embolization with AGB. Normal daily activity was recorded until sacrifice on the fourteenth day. There was no hepatic infarction in those embolized with AGB of 0.5 to 1.0 mm in diameter. Partial liver infarction was found in one with compelled embolization and in two with fragile beads. These observations suggested that AGB constitute an instantly preparable embolic material with slow-release activity and flexible solidity.

Alginates↗
PubMed1995

[Local cerebral blood flow and glucose metabolism during seizure in spontaneously epileptic El Mice].

Local cerebral blood flow and glucose metabolism were examined in spontaneously epileptic El mice using autoradiography with 125I-IMP and 14C-DG in the interictal phase and during seizure. El (+) mice that developed generalized tonic-clonic convulsions and El (-) mice that received no stimulation and had no history of epileptic seizures were examined. The seizure non-susceptible, maternal strain ddY mice were used as control. Uptake ratios for IMP and DG in mouse brain were calculated using the autoradiographic density. In the interictal phase, the pattern of local cerebral blood flow of El (+) mice was similar to that of ddY and El (-) mice, and glucose metabolism in the hippocampus was higher in El (+) mice than in El (-) and ddY mice, but flow and metabolism were nearly matched. During seizure, no significant changed blood flow and increased glucose metabolism in the hippocampus, the epileptic focus, and no markedly changed blood flow and depressed glucose metabolism in other brain regions were observed and considered to be flow-metabolism uncoupling. These observations have never been reported in clinical or experimental studies of epilepsy. Seizures did not cause large regional differences in cerebral blood flow. Therefore, only glucose metabolism is useful for detection of the focus of secondary generalized seizures in El mice, and appeared possibly to be related to the pathophysiology of secondary generalized epilepsy in El mice.

Animals↗
PubMed1994

[Intimal hyperplasia growth after stenting of modified gianturco Z stent in an experimental study].

Three types of modified Gianturco Z stents, which included some solder at the bend portion in group 1, a little solder in group 2 and no solder in group 3, were placed in the jugular vein in order to evaluate the degree of intimal hyperplasia growth in five dogs. Four weeks later, venography and histological examination after venectomy were performed. Stenosis was 32.7 +/- 6.9% at the bend portion in group 1, 27.0 +/- 6.0% in group 2 and 14.0 +/- 6.5% in group 3. The results indicate that stents without solder are preferable for the venous system.

Animals↗
PubMed1994

[A twining method for struts connection in Z-stents].

To compose Gianturco Z-stents without welding, a twining method was applied. The link portion of the struts of were spirally entwined by a thin stainless steel wire of 0.1 mm in diameter. The directional balance of spring force of the twined stents compared favorably with that of the conventionally welded stents. This twining method has theoretical benefit of less susceptible to corrosion than soldering. Then the twining method was thought to be beneficial in composing Z-stents.

Equipment Design↗
PubMed1994

Acute changes in liver gene expression in the N-nitrosodiethylamine-treated rat.

We constructed a complementary DNA (cDNA) library from mRNAs of rat liver induced by an initiating dose of a chemical carcinogen, N-nitrosodiethylamine (DEN). Using a differential hybridization with cDNA probes prepared from mRNAs of control and DEN-treated rat liver, eight cDNAs of which expression was altered by an acute single dose of DEN were cloned. Colony hybridization and nucleotide sequencing demonstrated six independent cDNA clones. These were known genes encoding liver-specific proteins such as microsomal epoxide hydrolase (mEH; epoxide hydrolase, EC 3.3.2.3), albumin, transthyretin, CYP2B7, CYP1A2 (microsomal cytochrome P450, EC 1.14.14.1) and argininosuccinate synthetase (EC 6.3.4.5). Quantitative Northern blot hybridization was carried out to measure the mRNA content of DEN-initiated rat liver at various times after DEN injection. We also analyzed the expression of glutathione transferase P (GST-P; glutathione transferase, EC 2.5.1.18), c-jun and glyceraldehyde-3-phosphate dehydrogenase (GAPDH; glyceraldehyde-phosphate dehydrogenase, EC 1.2.1.12). A single injection of DEN increased the mRNA levels of mEH, beta-actin and c-jun markedly and those of GST-P and GAPDH moderately, but decreased the mRNA levels of CYP2B7, CYP1A2, albumin and argininosuccinate synthetase. Transthyretin mRNA content was not changed, indicating that it was a false-positive clone picked up by chance. These dramatic changes in liver gene expression after acute exposure to DEN are discussed in terms of acute reactions to the massive damage to the DNA and self-defense mechanisms against toxic xenobiotics.

Animals↗
PubMed1994

Acute toxicity of lipiodol infusion into the hepatic arteries of dogs.

RATIONALE AND OBJECTIVES: The authors studied the acute toxicity of percutaneous transcatheter hepatic artery infusion of iodized poppy oil fatty acid ester (Lipiodol, Laboratoire Guerbet, Aulnay-sous-Bois, France). METHODS: Lipiodol dosages of 0, 0.25, 0.5, 1.0, and 2.0 mL/kg were infused into the hepatic arteries of 10 beagles. Enzymatic and radiographic alterations were assessed. RESULTS: After the infusion of Lipiodol, the dogs showed body weight loss and hypoalbuminemia attributable to decreased food intake, transient elevation of the aspartate transaminase and alanine transaminase, and continuous increase in alkaline phosphatase. The controls did not show any significant change. The radiographs obtained immediately after and 2 weeks after the infusion showed dose-dependent accumulation of Lipiodol in the liver. After 2 weeks, histologic examination of livers and lungs showed dose-dependent (r = .9) retention of oily droplets in sinusoids and pulmonary capillaries. Interlobar pericholangitis was found in four dogs infused with Lipiodol. Pulmonary inflammatory reaction was observed with capillary oil embolism. Oil droplets also were found in the pancreas and the brain. CONCLUSIONS: Lipiodol infusion of the hepatic artery resulted in dose-dependent circulation and embolism of Lipiodol droplets via sinusoids and via pulmonary capillaries into the systemic circulation.

Acute Disease↗
PubMed1994

t-PA activity in peripheral blood obtained from pregnant women.

Concentrations of tissue plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) were measured in blood obtained from pregnant women to elucidate the fluctuations in the fibrinolytic system which occur during the course of pregnancy. The t-PA activity was measured with a modified bioimmunoassay using anti-t-PA monoclonal antibody (SP-322) against a single chain of recombinant t-PA. The t-PA antigen was measured by ELISA using the same antibody. PAI activity was determined with a competitive inhibition assay of t-PA activity. In early pregnancy, t-PA activity was found to be close to the standard range seen in nonpregnant women, and gradually decreased during the course of pregnancy, then recovered to rise to the normal range within 48 hours after delivery. The t-PA antigen and PAI activity levels rose slowly during the course of pregnancy, and fell promptly after delivery. t-PA activity and t-PA antigen in levels in umbilical cord blood were higher after vaginal delivery than after cesarean section. These findings suggest that there may be an important physiological balance of the fibrinolytic system between mother and fetus during the course of pregnancy and the puerperium.

Female↗
PubMed1994

[Clinical evaluation on ofloxacin administered once daily in the treatment of acute uncomplicated cystitis].

A comparative study of ofloxacin (OFLX), a new oral quinolone, was carried out at the Department of Urology, Osaka University Hospital and its eighteen affiliated hospitals to evaluate the clinical efficacy and safety of daily dose of 300 mg, given either once daily dose (SID group), or in three divided doses (TID group), in the treatment of acute uncomplicated cystitis in women. Clinical efficacy was evaluated in 42 cases from the SID group, and 43 cases from TID group, respectively, according to the criteria by the Japanese UTI Committee. In the SID group, the clinical efficacy was evaluated as excellent in 29 cases, moderate in 12 and poor in 1, with an overall clinical effectiveness rate of 98%. In the TID group, it was evaluated as excellent in 25 cases, moderate in 17 and poor in 1, with an overall clinical effectiveness rate of 98%. Safety was monitored only by subjective complaints. In the SID group, no subjective side effects appeared (0%). In the TID group, one of the 43 women (2.3%) complained of borborygmus. These findings suggest that there was no significant difference between the two groups in the safety and efficacy of ofloxacin.

Acute Disease↗
PubMed1994

[Nippon Telegraph and Telephone Corporation workplace smoking control--a questionnaire survey of male NTT workers in the Tokyo area].

A survey of NTT workers regarding smoking control in their workplaces was conducted utilizing a questionnaire administered at the time of routine employee medical examinations. The questionnaire was self-administered and anonymous. Subjects were 1918 men, almost all who were involved in office work in the Tokyo area. Responses were obtained from 1872 (20's and 30's year of age 13.2%, 40's 68.1%, 50's 18.8%) after excluding 106 for incomplete responses. The results were as follows; 1. Of the subjects, 43.4% reported that smoking control was already in effect in their workplace. As for the method of smoking control, smoking restricted to specified places was the most common (31.1%). 2. Of smokers, only 9.8% approved of smoking control in their workplaces, 9.8% were opposed, and 80.1% of smokers reluctantly complied to smoking control in their workplaces. 3. About 60% of subjects, without distinguishing smoking habit, supported smoking restricted to specified areas as the method of smoking control. 4. Over 95% of smokers replied that they can successfully refrain from smoking in prohibited places. 5. For locations where they smoke, smokers listed employee lounge (91.5%), lavatory (83.7%), personal room (75.5%), at own desk (75.3%), reception room (72.7%) and conference room (64.3%). More than half of non-smokers replied that they disapprove of smoking in these places. These results suggest that smoking restricted to only specified places is most appropriate as the method of smoking control in the workplace. However differences exist between smokers and non-smokers as to appropriate designation of smoking areas and non-smoking areas.

Adult↗
PubMed1994

[Solitary metastasis to residual ureter resulting from renal cell carcinoma after radical nephrectomy: report of a case].

A case of solitary metastasis to residual ureter from renal cell carcinoma is reported. In November, 1987, a 56-year-old male had undergone left radical nephrectomy with renal cell carcinoma (clear cell subtype, G2, Inf alpha). He was doing well until June in 1989 when macroscopic hematuria occurred. A tumor from residual ureter with a large blood clot was detected on cystoscopy. A malignant tumor from the residual ureter was suspected and it was extirpated. Histological diagnosis revealed the same findings as the primary renal tumor. No other metastasis was detected. Only 8 cases of ureteral metastasis from renal cell carcinoma after radical nephrectomy have been previously reported in the Japanese literature.

Carcinoma, Renal Cell↗
PubMed1994

Radiological study of idiopathic Budd-Chiari syndrome complicated by hepatocellular carcinoma. A report of four cases.

During an 11-yr period (1979-1989), we have experienced five patients with idiopathic Budd-Chiari syndrome (BCS), four (80%) of whom had associated hepatocellular carcinoma (HCC). In contrast, the incidence of BCS complicated by HCC was 0.7% of a total of 556 patients who underwent surgery for HCC or were autopsied. Hepatitis B virus-related antigen or antibody was positive in one patient each. Four of our five patients were asymptomatic and were initially diagnosed by ultrasonography (n = 3) or computed tomography (n = 1). The hepatic parenchyma histopathological findings were cirrhosis and fibrosis in one each. Infection of hepatitis B virus rather than BCS was speculated as a causative factor for HCC in two patients. Membranous obstruction with spotty calcification, intrahepatic bizarre communicating vessels, and the dilated anterior longitudinal veins in spinal canal were recognized in three patients. Three patients had two HCCs which were similar in size and arose from the right and left hepatic lobe, separately, suggesting multicentricity of HCC. Both percutaneous transluminal angioplasty with Gruntzig balloon catheters for the obstruction of the inferior vena cava and hepatic arterial embolization for HCC(s) were performed in three patients. These patients survived 29.3 months on average after the diagnosis of BCS complicated by HCC(s). The opened IVC was confirmed to be patent on an average of 26.3 months after the first angioplasty.

Adult↗