Biomedical subjects

K Masuda

Publications and source records attributed to K Masuda.

At least 343 records · Page 19Linked to original sources

PubMed1995

Lymph-node metastases: efficacy for detection with helical CT in patients with gastric cancer.

PURPOSE: To determine the efficacy of helical computed tomography (CT) in the detection of lymphadenopathy in patients with gastric cancer. MATERIALS AND METHODS: Helical CT (5-mm section thickness, 5-mm/sec table incrementation) was performed in 58 patients (39 men, 19 women; mean age, 63.8 years) with gastric cancer; 1,082 lymph nodes (138 positive, 944 negative for metastasis) were resected at surgery. Findings at CT and resection were compared. Sensitivity for detecting lymph nodes was evaluated according to nodal size and presence of metastasis. RESULTS: Seven (1.1%) of 649 lymph nodes 1-4 mm, 160 (45.1%) of 355 nodes 5-9 mm, and 56 (72%) of 78 nodes larger than 9 mm were detected at CT. For nodes of at least 5 mm, sensitivity for detecting metastasis-positive nodes (79 [75.2%] of 105 nodes) was higher than that for detecting metastasis-negative nodes (137 [41.8%] of 328; P < .01). Differences between positive and negative nodes in CT attenuation (110 HU +/- 25 vs 66 HU +/- 32) and short-to-long axis ratios (0.81 +/- 0.15 vs 0.57 +/- 0.15; P < .001) were significant. CONCLUSION: Helical CT is effective for detection of metastatic lymphadenopathy from gastric cancer. CT attenuation and lymph-node configuration aid in diagnosis of malignant adenopathy.

Adult↗

PubMed1995

Effect of MPL 9000 extracorporeal shock wave lithotripsy on renal hemodynamics and urine flow: assessment by 99mTc-DTPA renal scintigraphy.

The effect of extracorporeal shock wave lithotripsy (ESWL) with an MPL9000 lithotriptor on renal hemodynamics and urine flow was investigated by 99mTc-DTPA renal scintigraphy. In the first-pass scintigrams obtained within 1 min after injection of 99mTc-DTPA, there was no significant change in the time to the maximum radioactivity level and the maximum radioactivity ratio at 1 day before ESWL and 1 day or 1 month after ESWL. However, analysis of 30-min scintigrams showed that urinary clearance of radioactivity was delayed in the treated kidney 1 day after ESWL, particularly in the region targeted by shock waves, despite the absence of overt urinary tract obstruction by residual stone fragments. This change was reversible and was no longer noted 1 month after ESWL. These results suggest that ESWL with the MPL9000 lithotriptor induces a focal and temporary decrease in urine flow in the treated kidney, but has little or no effect on renal hemodynamics.

Adult↗

PubMed1995

Time dependency of the acetazolamide effect on cerebral hemodynamics in patients with chronic occlusive cerebral arteries. Early steal phenomenon demonstrated by [15O]H2O positron emission tomography.

BACKGROUND AND PURPOSE: The acetazolamide effect is thought to reach a maximum at 10 to 20 minutes after administration. However, we sometimes encountered patients who showed a transient deterioration of ischemic symptoms several minutes after acetazolamide administration. We therefore considered that a steal phenomenon may occur before the acetazolamide effect reaches a maximum. We evaluated the time dependency of the acetazolamide effect on cerebral hemodynamics in patients with severe stenosis or occlusion of the unilateral internal carotid artery. METHODS: The subjects consisted of 13 patients with severe stenosis or occlusion of the unilateral internal carotid artery. Regional cerebral blood flow was measured at the resting state and at 5 and 20 minutes after the intravenous administration of 1 g acetazolamide by the use of the [15O]H2O bolus-injection method and positron emission tomography. The steal phenomenon was interpreted as positive when the regional cerebral blood flow values decreased by more than 10% after the administration of acetazolamide in more than one region of interest. RESULTS: A steal phenomenon was observed in 5 of 13 patients at 5 minutes after acetazolamide administration on the occlusive side, whereas it was observed in only 1 patient at 20 minutes. Thus, this phenomenon was observed more frequently in the early phase of the acetazolamide test. It was also observed more frequently in patients with poorly developed collateral circulation. CONCLUSIONS: Our acetazolamide [15O]H2O positron emission tomography study revealed an early steal phenomenon at 5 minutes after intravenous administration of acetazolamide, which may be a cause of the transient deterioration of ischemic symptoms during the acetazolamide test.

Acetazolamide↗

PubMed1995

A morphologic study of lung secretory leukoprotease inhibitor in pneumonia.

The present study was undertaken to determine the localization of cells laden with secretory leukoprotease inhibitor (SLPI) in bronchial/bronchiolar epithelium (B/Br-E) by histochemical techniques to see whether SLPI production occurs in conjunction with pathologic bronchopneumonia. Ten lung were obtained at autopsy from patients between 63 and 100 yr of age, including six with pathologic pneumonia and four without pneumonia. SLPI-laden cells in the B/Br-E corresponded mostly to goblet cells with apparent hyperplasia. A morphometric study performed on the B/Br-E indicated that the percentage of SLPI-laden cells was significantly correlated with the percentage of mucus-containing cells (r = 0.72, p < 0.001). This trend was similar in the bronchi (r = 0.60, p < 0.05) and in the bronchioles (r = 0.90, p < 0.01). The increased percentage of mucus and SLPI-laden cells in the B/Br-E was closely correlated with acute inflammatory changes in the adjacent alveoli, particularly in bronchi rather than in bronchioles. From these observations we conclude that the number of SLPI-laden cells in the airways increases in correlation with goblet cell hyperplasia. In addition, these morphologic changes are associated with the existence of acute inflammatory cell infiltration in the alveolar area.

Aged↗

PubMed1995

Isolation, characterization and biological activities of novel triprenyl phenols as pancreatic cholesterol esterase inhibitors produced by Stachybotrys sp. F-1839.

Ten triprenyl phenol metabolites were isolated as inhibitors of pancreatic cholesterol esterase from cultures of Stachybotrys sp. F-1839 by solvent extraction and column chromatographies. Combination of spectroscopic analyses revealed that two of these compounds are K-76 (1) and stachybotrydial (2), and that the remaining eight are new congeners (designated F1839-A (3), -B (4), -C (5), -D (6), -E (7), -F (8), -I (9) and -J (10). These compounds inhibited pancreatic cholesterol esterase by 50% at 6 x 10(-5) to 1.1 x 10(-1) M. Inhibition of the enzyme by compound 2, the most potent one among these compounds, was time-dependent and irreversible. When administered to normal rats, 2, at a single oral dose of 100 mg/kg, reduced [14C]cholesterol absorption by 50-60%. In cholesterol-fed mice, dietary supplementation of 2 (0.1%) for 14 days resulted in a 20% reduction in serum total cholesterol level without causing significant change in the high density lipoprotein cholesterol level.

Animals↗

PubMed1995

[Intra-bile duct growth of hepatocellular carcinoma: value of biliary dilatation on CT].

In order to evaluate the usefulness of CT in demonstrating biliary invasion by hepatocellular carcinoma, 191 surgically proved cases were studied. Among 191 CT scans performed before surgery, six (3%) showed biliary dilatation. Pathological biliary invasion was found in eight cases (4%). Of these eight cases, four cases (50%) showed biliary dilatation on CT. In six cases with biliary dilatation on CT, pathological biliary invasion was revealed in four cases (67%). In two cases, the large (> or = 6cm) encapsulated tumors located in the hepatic hilum dilated the intrahepatic bile duct without intraductal tumor growth. We concluded that biliary dilatation on CT cannot be a sign of biliary invasion by hepatocellular carcinoma.

Adult↗

PubMed1995

[Phase II clinical trial of the radioactive strontium (89Sr) chloride agent, SMS. 2P for pain palliation in patients with prostate cancer with bone metastases].

The phase II clinical trial of a strontium (89Sr) chloride agent (SMS. 2P) was performed in 9 patients with painful bone metastases secondary to prostate cancer. After an intravenous administration, 89Sr circulated in the plasma and was rapidly cleared. Urinary excretion varied widely among the patients. No serious acute side effects were observed. A mild transient increase in pain was reported by 4 patients 2-4 days after administration, two of whom complained of mild nausea or vomiting. All symptoms improved and never became a clinical problem. There were some abnormal hematological parameters. In particular, a decrease in the platelet level seemed to be a marrow suppression due to 89Sr irradiation. It is difficult to discriminate between the effects of 89Sr and the progress of the disease using tumor markers. The pain level improved within 2 weeks after administration and the effect continued for at least 8 weeks, which improved the quality of life for these patients.

Aged↗

PubMed1995

Combination chemotherapy with intra-arterial cisplatin and doxorubicin plus intravenous methotrexate and vincristine for locally advanced bladder cancer. Kyushu University Urological and Radiological Oncology Group.

PURPOSE: We evaluate the usefulness of neoadjuvant chemotherapy for bladder cancer. MATERIALS AND METHODS: The usefulness of neoadjuvant, modified methotrexate, vinblastine, doxorubicin and cisplatin chemotherapy was evaluated in 36 patients with locally advanced bladder cancer. RESULTS: Of 36 patients 12 achieved a clinical complete response and 17 had a partial response. Of the 12 patients who achieved a clinical complete response the bladder was preserved in 11 and all patients were disease-free at a median of 33 months. No significant toxicity was observed. CONCLUSIONS: This chemotherapy is useful for locally advanced bladder cancer and the feasibility of bladder preservation in patients with a clinical complete response was suggested.

Adult↗

PubMed1995

[HLA-DR2 alleles and uveitis in leprosy].

In order to investigate the role of immunogenetic factors in the pathogenesis of uveitis in leprosy, HLA antigens were analyzed between the leprotics with and without uveitis. Sixty-five Japanese leprosy patients comprised 32 with uveitis and 33 without uveitis. Controls consisted of 138 healthy subjects. A lymphocyte cytotoxicity test was used for typing HLA-A, -B, -C, -DR and -DQ antigens. HLA-DR2 genotyping was performed by the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and PCR-restriction fragment length polymorphism (RFLP) methods. The frequency of HLA-DR2 antigen was significantly increased in the patients with uveitis as compared with the control subjects (Pc < 0.0005), whereas HLA-DR53 antigen was significantly decreased (Pc < 0.05). At the genomic level the frequency of HLA-DRB1*1501 was significantly increased in the patients with uveitis and without uveitis as compared with that in the controls. The association with DRB1*1501 was even stronger in patients with uveitis (odds ratio = 7.1, Pc < 0.000005) than in the patients without uveitis (odds ratio = 4.1, Pc < 0.005). Our results suggest that HLA-DRB1*1501 contribute to the susceptibility to uveitis in the Japanese with leprosy.

Alleles↗

PubMed1995

[Endothelin-1 and intraocular inflammation in pigmented rabbit eyes].

We assessed the role of endothelin-1 (ET-1) in the development of anterior chamber inflammation in pigmented rabbit eyes. After the injection of ET-1 (10(-13), 10(-11), 10(-9) or 10(-7) M) into the anterior chamber, aqueous protein concentration increased significantly in a dose-dependent fashion, with a peak at 1 to 2 hours after treatment, and it returned to the normal level 8 hours after the injection. Pupillary diameter was significantly reduced when 10(-9) M or 10(-7) M ET-1 solution was injected. These effects were blocked by pretreatment with anti-prostaglandin agents, i.e., topical indomethacin or venous diclofenac sodium. In the endotoxin-induced experimental uveitis model, ET-1 concentration in the aqueous humor was significantly higher than that of normal controls as well as the plasma ET-1 level. These results suggest that ET-1 is an important mediator in the ocular inflammatory reactions through the arachidonic acid cascade.

Animals↗

PubMed1995

Circadian rhythms in aqueous protein concentration and intraocular pressure in rabbits.

Circadian rhythms in aqueous protein concentration (APC) and intraocular pressure (IOP) were examined in Dutch rabbits using the laser flare-cell meter and a pneumatonometer. The reproducibility and seasonal changes in circadian rhythm were also investigated. Rabbits were trained to a lighting cycle of 12-hour light and 12-hour darkness. The mean value of reproducibility coefficients obtained with re-examination at 2-week intervals was 21.9% in the reading of the laser flare-cell meter. APC was reduced during the dark phase, and increased rapidly and remained high during the light phase. On the other hand, IOP showed an inverse circadian rhythm which was negatively correlated with that of APC. The total average of APC throughout 24 hours was 39.1 +/- 28.3 (mean +/- SD) mg/100 ml equivalent of bovine serum albumin, which agreed with the previous data. Seasonal changes in circadian rhythm were not statistically significant either in APC or in IOP.

Animals↗

PubMed1995

Functional Rescue of photoreceptors from the damaging effects of constant light by survival-promoting factors in the rat.

PURPOSE: To investigate whether and how survival-promoting agents rescue photoreceptor cell function and morphology from constant light damage, the authors recorded electroretinographic (ERG) responses and examined light micrographs of retinas in those rats given intravitreal injection of midkine (MK) and basic fibroblast growth factor (bFGF) before constant exposure. METHODS: Albino Sprague-Dawley rats were injected with MK, bFGF, or phosphate-buffered saline (PBS) 2 days before the onset of 1 week of constant light. ERG responses were recorded using white flash stimuli with the intensity range of 4 log units, followed by histologic examinations of retinas, including quantitative assessment of the outer nuclear layer thickness as an index of photoreceptor cell loss. RESULTS: ERG responses were barely detectable in uninjected eyes after 1 week of constant light. On the other hand, distinct responses were recordable in eyes injected intravitreally with MK and bFGF, and the degree of ERG rescue in terms of the amplitude of b-wave was approximately 40% to 60% compared with normal eyes. Intravitreally injected PBS showed slight, but noticeable, preservation of ERG responses as well. Histologic examination revealed that MK and bFGF protected photoreceptors from light damage. A good correlation was found between anatomic rescue of photoreceptors as assessed by outer nuclear layer thickness and the functional rescue as defined by the magnitude of ERG responses. CONCLUSIONS: Functional and anatomic rescue of photoreceptors in albino rats from constant light damage is achieved by prior intravitreal injection of MK and bFGF.

Animals↗

PubMed1995

[A comparison of the cerebrovascular responses to CO2 and Diamox in patients with unilateral occlusive cerebral arteries: a H2(15)O PET study].

We studied the relationship between the cerebrovascular responses to CO2 and Diamox in patients with chronic cerebrovascular diseases. The subjects consisted of 11 patients with unilateral occlusive or highly stenotic carotid artery. The cerebral blood flow was measured at the resting state, during the inhalation of 5% CO2, at both 5 and 20 min after Diamox i.v. (1 g). The rCBF ratios (occlusive/non-occlusive side) during the inhalation of CO2 and 20 min after Diamox i.v. closely correlated with each other. However, the ratio at 5 min after Diamox i.v. was slightly lower than that during the inhalation of CO2. The percent increases of rCBF also showed a significant correlation between 5% CO2 inhalation and 20 min after Diamox i.v. However, the rCBF decreased inversely at 5 min after Diamox i.v. in some regions on the occlusive side, which indicates the presence of a so-called "steal phenomenon". The percent increases in the rCBF after 1 g Diamox i.v. were more or equal to those during the inhalation of 5% CO2. The CO2 and Diamox were thus considered to be equally useful in the evaluation of the perfusion reserve capacity. However, these various characteristics as described above should be considered in the clinical practice.

Acetazolamide↗

PubMed1995

MR imaging of hepatocellular carcinoma. Correlation of metal content and signal intensity.

In order to clarify the factors contributing to the signal intensities (SIs) of HCC on T1-weighted images, the amount of water, lipid, copper (Cu), iron (Fe), and manganese (Mn) was determined in HCC and surrounding hepatic parenchyma of 13 patients. The relationships among these findings, the histopathologic findings, and the SIs of T1-weighted images were evaluated. Among the 13 HCC, 3 had a high SI, 5 were isointense, and 5 had a low SI on T1-weighted images compared to the surrounding hepatic parenchyma. The paramagnetic ions which contributed to the SI patterns were assumed to be Cu in HCC (38.0 +/- 62.4 micrograms/g ww), and Fe in the liver (61.1 +/- 42.4 micrograms/g ww) and HCC (40.0 +/- 34.3 micrograms/g ww). In 8 HCC with high- or isointensity, 2 were grades I, 5 were grade II, and one was grade III according to the Edmondson-Steiner's histopathologic classification. It is concluded that the SI patterns alone can not be a sign of low grade malignancy because of the existence of Fe in livers and HCC.

Aged↗

PubMed1995

[The relationship between the cerebral blood flow, oxygen consumption and glucose metabolism in primary degenerative dementia].

The CBF, CMRO2 and CMRGlu were measured in patients with primary degenerative dementia including 5 patients with dementia of Alzheimer's type and 4 patients with Pick's disease, and then the correlation between the cerebral blood flow and energy metabolism was evaluated. The control subjects consisted of 5 age-matched normal volunteers. The CBF, CMRO2 and CMRGlu decreased in the bilateral frontal, temporal and parietal regions in the patients with Alzheimer's dementia, while they decreased in the bilateral frontal and temporal regions in the patients with Pick's disease. Both the CBF and CMRO2 were closely correlated with each other. However, the CMRGlu was more severely impaired than the CBF or CMRO2 in both pathological conditions. These results suggested that CMRGlu began to decrease before the reduction of the aerobic metabolism and thus measuring the CMRGlu is considered to be the most sensitive method for detecting abnormal regions in primary degenerative dementia.

Aged↗

PubMed1995

[Clinical usefulness of urinary anti HIV antibody test--a large scale study from 11 institutes in Japan].

An enzyme immuno assay kit has been developed to detect anti-HIV antibody in urine. In order to examine the clinical utility of the kit, 1333 urine samples were assayed. These samples consisted of 233 urine samples from HIV infected patients, 472 samples from HIV uninfected patients including 203 samples from patients with urogenital diseases, and 628 samples from normal subjects. Anti-HIV antibodies were detected in all the urine samples from HIV infected patients, and the diagnostic sensitivity for HIV infection was 100% with no false negative cases. A variety of anti-HIV antibody titers were found in the urine samples from HIV infected patients. However, no significant differences were found in the distribution patterns of urinary anti-HIV antibody titers among AC, ARC and AIDS patients. False positives were determined in only five samples in 628 healthy subjects (0.8%), one in 19 patients with hepatitis (5.3%), one in 45 patients with hemophilia (2.2%) and two in 105 pregnant women (1.9%). The antibody titers of all the false positive samples in these groups were less than the cut-off index multiplied by two. However, relatively high positive rates were demonstrated in the samples from urogenital diseases (11.8%), diabetes mellitus (20.0%) and auto-immune diseases (7.3%). False positive results were found to be directly correlated to the protein concentration of urinary protein, especially the immunoglobulin concentration in urine. The assay system was also evaluated by various reproducibility tests performed by different operators at different laboratories. The test results were satisfactory.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗

PubMed1995

Serum markers of systemic disease processes in osteoarthritis.

Serum levels of several molecules originating from joints and cartilages have been shown to rise during the preradiological stages of osteoarthritis (OA). Using a dog model of posttraumatic OA, we have shown that serum levels of markers of aggrecan degradation (antigenic keratan sulfate) and synovial proliferation/metabolism (hyaluronan) rise within 1-2 weeks after the injury and remain elevated for at least 13 weeks. These changes, which precede the development of OA lesions, are consistent with the view that traumatic injury to a single synovial joint gives rise to a state of hypermetabolism that is local at first but becomes systemic with time.

Aggrecans↗

PubMed1995

Noncalcified pulmonary tuberculomas: CT enhancement patterns with histological correlation.

The objective of this study was to correlate enhanced CT images of noncalcified tuberculomas with histological findings, in order to search for characteristic CT enhancement patterns. Over 7 years, 12 noncalcified tuberculomas were surgically resected. Enhanced CT images of these tuberculomas were reviewed and correlated with histological studies. Ring or central-curvilinear enhancement was present in nine of 12 tuberculomas (75%). In those with ring or central-curvilinear enhancement, the low-density region was histologically confirmed to be caused by caseous or liquefied necrotic material, and a von Willebrand factor stain showed moderate to marked vascularity of the enhanced areas. Three tuberculomas showed nonspecific enhancement patterns. Histologically, each of these contained central caseous necrotic material, and two showed a poor vascularized peripheral fibrotic zone.

Aged↗