Biomedical subjects

C Kuroda

Publications and source records attributed to C Kuroda.

At least 19 recordsLinked to original sources

PubMed1995

Endoscopic ultrasonography in diagnosis and staging of pancreatic cancer.

The accuracy of endoscopic ultrasonography (EUS) for diagnosis of pancreatic cancers was evaluated in consecutive 232 patients with possible pancreatic cancer, and that for assessment of their locoregional spread was evaluated in 28 patients with pancreatic cancer subjected to pancreatectomy, in comparison with the accuracies of transabdominal ultrasonography (US) and computed tomography (CT). EUS was found to be significantly more accurate than US or CT and was especially useful for detecting small pancreatic cancers of less than 2 cm in diameter. With EUS, pancreatic cancers could be detected as a hypoechoic mass with a relatively unclear margin and irregular internal echoes. EUS was also more sensitive than CT and US for detecting venous and gastric invasions: it was more useful for detecting direct invasion of pancreatic cancers when the tumors were less than 3 cm in diameter. These findings indicate that EUS is an accurate method for diagnosis of pancreatic cancer and assessment of their locoregional spread and is particularly useful for detecting small tumors.

Endoscopy, Digestive System↗

PubMed1995

Comparative safety and efficacy of two immune globulin products in Kawasaki disease.

OBJECTIVE: To compare the safety and efficacy of various intravenously administered immune globulin (IVGG) products in patients with Kawasaki disease. METHODS: We performed a retrospective matched-pair study of 45 pairs of patients, matched by age, gender, hospital, and illness day when IVGG therapy was initiated. All patients received aspirin, 80 to 100 mg/kg per day; one of each pair received Venoglobulin, 2 gm/kg (product A), and the other received Iveegam, 2 gm/kg (product B). Safety was assessed during and after IVGG infusion by recording rigors, pruritus, hypotension, urticaria, and nausea. Treatment efficacy was evaluated by posttreatment height and duration of fever, and subsequent echocardiographic changes. RESULTS: Untoward reactions during infusions occurred more often with product A (25%) than with product B (2%) (p < 0.025); most reactions were rigors (18% vs 2%) (p < 0.05). Therapy was completed in all patients. Height of fever and proportion of patients febrile each day after product A or B did not differ significantly. No differences were found in the frequency of coronary artery abnormalities 1 year after illness. CONCLUSIONS: No significant differences in efficacy appeared between the two IVGG products, but they differed significantly in non-life-threatening adverse reactions, especially infusion-related rigors. Other IVGG products should be evaluated in a similar fashion.

Child↗

PubMed1995

G10BP, an E1A-inducible negative regulator of Sp1, represses transcription of the rat fibronectin gene.

Downregulation of the fibronectin (FN) gene in a rat 3Y1 derivative cell line, XhoC, transformed by the adenovirus E1A and E1B genes seems to be caused by the induction of a negative regulator, G10BP, which binds to three G-rich sequences in the promoter (T. Nakamura, T. Nakajima, S. Tsunoda, S. Nakada, K. Oda, H. Tsurui, and A. Wada, J. Virol. 66:6436-6450, 1992). These are the G10 stretch and two GC boxes consisting of the G10 stretch with one internal C residue insertion. The recognition sequences of G10BP and Sp1 (GGGCGG) overlap in these GC boxes. To analyze the mechanism of the downregulation, G10BP was purified by DNA affinity chromatography, and its molecular mass was estimated to be about 30 kDa. The promoter was modified by substituting the sequence GGGG with ATCC or CTTA in these G-rich sequences, leaving the Sp1 motif intact, and by replacing the Sp1 motif by the T stretch. Transcription of FN promoter-chloramphenicol acetyltransferase fusion genes carrying the base substitution in one or more of these G-rich sequences both in vivo and in vitro revealed that the base substitution in any G-rich sequence results in reduction of promoter activity, although the downstream GC box (GCd) plays a primary role. The addition of G10BP severely inhibited the activities of the FN promoters carrying the wild-type GCd in vitro, while the promoters carrying the mutant GCd were unaffected. The binding affinity of G10BP and Sp1 to each of the G-rich sequences, analyzed by gel shift assays, indicated that G10BP binds strongly to the GCd, moderately to the G10 stretch, and weakly to GCu, while Sp1 binds strongly to GCu, moderately to GCd, and weakly to the G10 stretch. Sp1 binding to GCd and the G10 stretch was inhibited by G10BP, while binding to GCu was unaffected. These results indicate that FN gene transcription is inhibited in XhoC cells primarily by exclusion of Sp1 binding to GCd by G10BP and that G10BP is a new class of Sp1 negative regulator.

Adenovirus E1A Proteins↗

PubMed1994

[Evaluation of multislice dynamic MR imaging of the whole liver].

In 47 patients with liver cirrhosis, we performed dynamic MRI with a multisection FLASH technique that enabled us to obtain 13 T 1-weighted images of the entire liver within a single breath hold. Computed tomographic arterial portography (CTAP), US, CT, angiography (AOG) and MRI (spin echo [SE] and dynamic MRI) were performed in all 47 patients. Except for cyst, hemangioma and metastatic tumor, 104 focal nodules less than 3 cm in diameter were detected. These 104 focal lesions were divided into three groups according to the pattern of CTAP: 69 portal supply negative, 11 portal supply decreased, and 24 portal supply normal. In the portal supply negative group, 63 lesions (91%) were detected by dynamic MRI, which was superior to other modalities (US 77%, CT 41%, AOG 70%, MRI-SE 61%). The superiority of dynamic MRI resulted from its excellent ability to detect liver lesions less than 1 cm in diameter. We confirmed histologically that dynamic MRI had almost the same ability to detect hepatocellular carcinoma (HCC) as CTAP. Dynamic MRI should be clinically useful as a noninvasive examination for the detection of HCC.

Carcinoma, Hepatocellular↗

PubMed1994

Developing a new picture archiving and communication system for the new Osaka University Hospital.

Osaka University Hospital moved into a new hospital building on the suburban Suita campus in October 1993. A newly developed hospital information system, a new radiologic information system and phase I of a completely new Picture Archiving and Communication System (PACS) also began operating. Work began in 1986 on this PACS. The PACS effort has been guided by one working group and two committees during the last 7 years. A survey of the previous diagnostic and image delivery system was performed as part of the preamble to designing an optimal PACS. Extensive analysis and measurement of pre-existing operational conditions was undertaken. These studies and technical research projects are described in a companion paper in this issue. The phase I hardware installation and initial testing were completed in March 1994. Subsequent phases will build incrementally until the completely new, hospital-wide PACS is realized.

Computer Systems↗

PubMed1994

Initial data-element selection for the evaluation of picture archiving and communication system performance.

The completely new, hospital-wide picture archiving and communication system (PACS) now being implemented at Osaka University Hospital is described elsewhere in this issue. This paper lists the many studies of the department and hospital that were performed before the PACS for the purpose of identifying data elements for use in evaluating a PACS system. A second purpose of the initial data-element collection was to assist in the overall Osaka University PACS design. Selected studies from this work are presented here.

Computer Systems↗

PubMed1994

A comparison of conventional screen-film radiography and hard copy of computed radiography in full and two-thirds sizes in detection of interstitial lung disease.

This study examined whether hard-copy radiographs produced from computed radiography (CR) images show the subtle interstitial pulmonary disease equally well to conventional screen-film radiographs, because a digital radiography should be chosen for introduction of the digital picture archiving and communication system (PACS) for the new Osaka University Hospital. Eleven radiologists examined 20 abnormal and 20 control chest radiographs presented in each of three groups: conventional screen-film radiographs and two sizes of hard-copy radiographs made from CR images. This study of digital image quality of chest examinations found that some findings on conventional screen-film radiography images are not reproduced by current CR (2,000 x 2,000 x 10 bits in matrix), especially when the experienced radiologists were observed. This finding suggested improvements are needed in CR before CR of chest should fully replace conventional screen-film radiography.

Hospitals, University↗

PubMed1994

Small PACS for digital medical images--reliability and security in a clinical setting.

Recently we introduced a small Picture Archiving Communication System (PACS) for handling CT and MRI data. Our experience with this system has been useful in identifying potential problems in a clinical setting. Since the use of PACS raises both medical and social concerns, it cannot be instituted without addressing concerns related to the reliability and security issues. Although PACS is useful in the management of medical images, there are concerns about their reliability and security in a clinical setting. Reliability encompassed image quality, timeliness of the reports, and the PACS to the Radiological Information System (RIS) interface including the retrieval of the previously obtained images. The security of the patient's medical data is also essential.

Computer Security↗

PubMed1994

Comparison between conventional and spiral CT in patients with hypervascular hepatocellular carcinoma.

To determine the usefulness of spiral CT in the detection of hypervascular hepatic lesions, we compared conventional contrast enhanced CT (CECT) with whole liver dynamic scanning during the artery-dominant phase by spiral CT (SDCT), using hypervascular hepatocellular carcinoma (HCC) as a model. Twenty-nine patients with 56 hypervascular nodular type HCCs detected by hepatic digital subtraction angiography were examined by both CT techniques. These nodular type HCCs were divided into three groups according to diameter: < 10 mm (n = 7), 10-20 mm (n = 17), and over 20 mm (n = 32). None of seven lesions less than 10 mm in diameter was seen by either technique. Of 17 lesions 10-20 mm in diameter, four (24%) were detected by precontrast CT plus CECT, whereas 14 (82%) were detected by precontrast CT plus SDCT. There were no lesions detected by CECT only, whereas 10 lesions were detected by SDCT only (P < 0.01 by signed test). For 32 lesions over 20 mm in diameter, there was no significant difference in detection rates between the CT techniques. Our results indicate that spiral CT is useful for the detection of relatively small hypervascular hepatic lesions such as hypervascular HCCs.

Adult↗

PubMed1993

[Differentiation of bronchogenic carcinoma from benign nodule by MR imaging: quantitative evaluation].

To distinguish benign from malignant nodules with MR imaging, 39 pulmonary nodules (23 bronchogenic carcinomas, nine tuberculomas and seven other benign lesions) were studied. MR equipment of 1.5 Tesla was used, and relative signal intensities of pulmonary nodules on T 2- and T 1-weighted images before and after administration of gadopentate dimeglumine were evaluated. On T 2-weighted images, the relative signal intensity of bronchogenic carcinomas to subcutaneous fat was 5.48 +/- 1.69, that of tuberculomas was -2.56 +/- 2.22 and that of other benign lesions was -0.88 +/- 3.37; the difference between tuberculomas and bronchogenic carcinomas was statistically significant (p < 0.05). On T 1-weighted images before and after administration of gadopentate dimeglumine, the relative signal enhancement of bronchogenic carcinomas was 17.6 +/- 2.0, that of other benign lesions was 20.0 +/- 5.2 and that of tuberculomas was -0.0074 +/- 0.763; the difference between tuberculomas and bronchogenic carcinomas as well as benign nodules was statistically significant (p < 0.001). The relative signal intensity on T 2-weighted images and the ratio of signal enhancement to noise could differentiate tuberculomas from bronchogenic carcinomas and other benign lesions. However, bronchogenic carcinomas and other benign lesions could not be differentiated by MR imaging.

Aged↗

PubMed1993

MR imaging of oculomotor nerve neurilemmoma.

The authors present a proved case of neurilemmoma arising from the oculomotor nerve in which MR imaging, including enhancement by gadopentetate dimeglumine, dynamic study and three-dimensional gradient echo images, provided much more precise definition of the tumor.

Adult↗

PubMed1993

MR angiography of meningioma.

The clinical evaluation of three-dimensional time-of-flight MR angiography was prospectively performed in 16 patients with intracranial meningioma. MR angiographic techniques used in this study both with and without gadopentetate dimeglumine made it possible to demonstrate the topographic relationship between the tumors and the neighboring vascular structures. MR angiograms were compared with available conventional angiograms. The three-dimensional enhanced MR angiograms were successful in depicting sinus involvement in greater detail in six patients than conventional angiography. In six patients, the feeding arteries of meningiomas were demonstrated with the unenhanced MR angiograms. However, MR angiograms failed to show small feeding arteries in three patients as delineated with conventional angiography. Arterial displacement was shown in nine patients. Venous drainage and collateral circulations were also visualized in four patients. Our results indicate that multiview MR angiograms noninvasively provide useful information for planning the surgical treatment of patients with meningioma.

Cerebral Angiography↗

PubMed1993

Magnetic resonance imaging-histologic correlation of small hepatocellular carcinomas adenomatous hyperplasias.

RATIONALE AND OBJECTIVES: Hepatocellular carcinomas (HCCs) usually consist of components of different histologic grade. Using surgically resected specimens, the authors obtained high-resolution magnetic resonance (MR) images and studied the relationship between histologic grade of HCCs and MR signal intensity. METHOD: In vitro MRI was performed on 15 small (less than 20-mm diameter) HCCs and 2 patients with adenomatous hyperplasia (AH) within 1 hour of surgical resection. In these 17 lesions, 24 macroscopic nodular components corresponding to MR images were recognized pathologically. The difference in MR signal intensity was examined by using tumor/phantom (T/P) signal-intensity ratio. In addition, the correlations between signal intensity on MRI and histologic criteria for grading HCC were studied. RESULTS: On T2-weighted images, grade II HCCs had significantly greater T/P values than grade I HCCs (P < .01). There is the correlation (r = .88, P < .001) between nucleocytoplasmic (N/C) ratio and signal intensity of small HCCs and AHs on T2-weighted images. CONCLUSION: The N/C ratio is an important factor relating the signal intensity to the histologic grade of these lesions on T2-weighted images.

Aged↗

PubMed1993

Bladder tumors: staging with gadolinium-enhanced oblique MR imaging.

To clarify the importance of imaging plane in evaluation of invasion by tumor into muscle, 50 patients with bladder tumors underwent examination with magnetic resonance (MR) imaging performed with an oblique plane and the early phase of contrast enhancement. After the ideal oblique plane was selected, an oblique T2-weighted image was obtained. Gadopentetate dimeglumine was then administered, and an oblique T1-weighted image was obtained. The staging based on oblique T2-weighted and oblique contrast material-enhanced T1-weighted MR images was then correlated with histopathologic staging. The respective accuracies of oblique contrast-enhanced T1-weighted and oblique T2-weighted images were 78% and 60% for overall staging (P < .05), 90% and 74% for differentiation between (a) stage T1 and lower-stage tumors and (b) stage T2 and higher-stage tumors (P < .05), and 92% and 88% for differentiation between (a) stage T2 and lower-stage tumors and (b) stage T3a and higher-stage tumors (P > .05). Oblique MR imaging performed in conjunction with the early phase of contrast enhancement showed significantly high staging accuracy, especially in differentiation between superficial tumors and tumors with superficial muscle invasion.

Adult↗

PubMed1993

Response to transcatheter oily chemoembolization in hepatocellular carcinoma 3 cm or less: a study in 50 patients who underwent surgery.

The response of 50 patients who underwent hepatectomy for hepatocellular carcinoma measuring 3 cm or less (at the time of surgery) to transcatheter oily chemoembolization was evaluated. The response was assessed in 5 categories, A: complete necrosis (100%), B: necrosis of at least 95%, C: at least 80%, but less than 95%, D: at least 50% but less than 80%, and E: less than 50% of the tumor cells. Response A was observed in 19 patients (38%), B in 7 (14%), C in 9 (18%), D in 7 (14%), and E in 8 (16%). These results were classified with respect to the histological degree of tumor differentiation, the WHO histological classification, the microscopic patterns of tumor growth, and macroscopic classification. The response was evaluated in relation to the histological grade of tumor differentiation and the WHO histological classification in all categories of response except response A, and there was no significant difference between the categories. The response was obviously better with the expansive type than with the replacing type. Single nodular type lesions were more responsive than the single nodular type lesions with extranodular growth and the contiguous multinodular type. Pretreatment estimation of the microscopic patterns of tumor growth and macroscopic classification appears to be valuable in predicting prognosis.

Adult↗

PubMed1992

[Regenerating nodules in liver cirrhosis--patho-MR-serological correlation study].

An MR study was performed in 73 clinically diagnosed cirrhotic patients to determine correlations among the demonstration of small low intensity nodules (SLINs), secondary changes due to cirrhosis, and serological data. In 32 patients, liver cirrhosis was proved histologically. SLINs were observed in 38 of the 73 patients on gradient echo (GRE) images and in 28 patients on T2-weighted SE images. Patho-MR correlation study of the liver in the 32 histologically proved cirrhotic patients revealed that SLINs were seen on GRE images only in patients with iron deposits in regenerating nodules (RNs). There was no significant correlation between secondary changes due to liver cirrhosis and the demonstration of SLINs. Serological data indicating liver cell injury and iron store in the body were significantly higher in patients with iron deposits in RNs than in those without iron deposits.

Adult↗

PubMed1992

Prospective and randomized clinical trial for the treatment of hepatocellular carcinoma--a comparison of lipiodol-transcatheter arterial embolization with and without adriamycin (first cooperative study). The Cooperative Study Group for Liver Cancer Treatment of Japan.

A randomized, controlled clinical trial comparing the use of lipiodol-transcatheter arterial embolization (L-TAE) in the presence versus the absence of Adriamycin (ADR) for the treatment of hepatocellular carcinoma was conducted from August 1988 through September 1989. In all, 125 Japanese hospitals participated in this study and 289 patients were entered in the trial. The patients were randomly allocated into group A (L-TAE) or group B (L-TAE + ADR) by telephone registration. There was no significant difference in background factors between group A and group B. Additional treatment, including repeated TAE or hepatic resection, was given to 189 patients. Among the four endpoints analyzed, the rate of tumor reduction and lipiodol accumulation in the tumor did not significantly differ between the two groups. The 3-year survival values for groups A and B were 33.6% and 34.9%, respectively; the difference was not significant. The serum alpha-fetoprotein level, however, decreased to a significantly greater extent in the group that received ADR than in the group that did not (P < 0.05). This result suggests that ADR has some favorable additional effect in L-TAE for the treatment of hepatocellular carcinoma.

Adult↗

PubMed1992

Prospective and randomized clinical trial for the treatment of hepatocellular carcinoma--a comparison of L-TAE with Farmorubicin and L-TAE with adriamycin (second cooperative study). The Cooperative Study Group for Liver Cancer Treatment of Japan.

A randomized clinical trial comparing L-TAE with Farmorubicin (FARM) and L-TAE with Adriamycin (ADR) in the treatment of hepatocellular carcinoma was conducted from October 1989 through December 1990. In all, 192 hospitals participated in this study and 117 patients were entered. The patients were randomly allocated to group A (L-TAE+FARM) or group B (L-TAE+ADR). There was no significant intergroup difference in background factors. Additional treatment consisting of repeated TAE or surgery was given to 66 patients. Four factors were analyzed in this study: the percentage of reduction in tumor size, the change in the AFP level, lipiodol accumulation, and survival. None of these factors differed significantly between the two groups. The final evaluation of this study will be based on differences in survival after a long-term follow-up. Toxic effects manifested less frequently in group A than in group B, and the decrease in the platelet count in the peripheral blood was significantly lower in group A than in group B. These results suggest that FARM exerts a more favorable effect than does ADR in the treatment of hepatocellular carcinoma.

Adult↗