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H Honda

Publications and source records attributed to H Honda.

At least 649 records · Page 36Linked to original sources
PubMedDate not supplied

CD34 expression in endothelial cells of small hepatocellular carcinoma: its correlation with tumour progression and angiographic findings.

The angiogenic process plays an important role in tumour growth and metastasis during hepatocarcinogenesis, but it is still uncertain when the process begins during tumour formation. Forty-two small hepatocellular carcinomas (HCC) that measured either less than or equal to 2 cm in diameter were studied by comparing the histologic findings with the angiographic findings, and with immunohistochemical expression of endothelial marker QB-end/10 (QB), a new monoclonal antibody raised against CD34, in the sinusoidal wall. Twenty (91%) of 22 moderately or poorly differentiated HCC revealed a positive reaction for QB, while only eight (40%) of 20 well differentiated HCC demonstrated a positive reaction (P < 0.01). In the tumours showing a 'nodule in nodule' appearance, the less differentiated areas were more reactive for QB. Twenty-three (82%) of 28 QB positive tumours were hypervascular, while only three of 14 (21%) QB negative tumours were hypervascular (P < 0.01) by angiography. All six of the poorly differentiated and 13 (81%) of the 16 moderately differentiated tumours were hypervascular, while only seven (35%) of 20 well differentiated HCC were hypervascular (P < 0.01). These results indicate that as the tumour becomes less differentiated, the QB positive areas become wider and angiography demonstrates hypervascularity. We therefore speculate that the HCC sinusoids acquire the characteristics of capillary and precapillary blood vessels during de-differentiation from well to moderate, and thus the tumour begins to reveal hypervascularity on angiography. The above process may be correlated with the stepwise progression of HCC.

Antigens, CD34↗
PubMedDate not supplied

Spectrum of CT findings in nonmalignant disease of the adrenal gland.

Computed tomography (CT) plays a leading role in the evaluation of nonmalignant disease of the adrenal gland. CT is highly accurate in the localization of adrenal masses in patients with diseases associated with hyperfunctioning adrenal glands such as Cushing syndrome and Cushing disease, Conn syndrome, adrenal tumors leading to virilization or feminization, and pheochromocytomas. CT permits a specific diagnosis of acute or subacute adrenal hematoma and myelolipoma. Hematomas are round to oval and have increased attenuation (50-90 HU) that decreases on follow-up CT scans. Myelolipomas typically manifest as a well-defined suprarenal mass with an attenuation of-30 to -115 HU. Adrenal cysts are usually round to oval and manifest as a hypoattenuating mass with a smooth, thin wall. CT is useful in the evaluation of patients with Addison disease, particularly the subacute form secondary to tuberculosis or disseminated histoplasmosis. Findings typically include bilateral adrenal enlargement with a central necrotic area of hypoattenuation and peripheral enhancement. Thin-section unenhanced CT permits accurate measurement of attenuation and can be used to differentiate adrenal adenoma from metastasis in a cancer patient with an indeterminate mass: Attenuation of 10 HU or less usually indicates adenoma rather than cancer. If the mass is found incidentally at contrast material-enhanced CT, delayed scans obtained as early as 5-15 minutes after intravenous administration of contrast material appear to have comparable accuracy.

Addison Disease↗
PubMedDate not supplied

Pitfalls in MR cholangiopancreatographic interpretation.

Magnetic resonance (MR) cholangiopancreatography (MRCP) is widely used in the evaluation of pancreatobiliary disorders. However, numerous related pitfalls may simulate or mask pancreatobiliary disease. Maximum-intensity-projection (MIP) reconstructed images completely obscure small filling defects and may demonstrate respiratory motion artifacts. T2 weighting may vary with different MR imaging sequences and influence MRCP findings. Incomplete imaging may create confusion regarding ductal anatomy or disease. Furthermore, MRCP yields only static images and thus may fail to depict various anomalies. Limited spatial resolution makes differentiation between benign and malignant strictures with MRCP alone extremely difficult. Susceptibility artifacts may be caused by metallic foreign bodies or gastric-duodenal gas. Fluid accumulation may produce a pseudolesion or pseudostricture, although changing the imaging angle or section thickness may be helpful. Pneumobilia may be misinterpreted as bile duct stones, and true stones may be overlooked. Pulsatile vascular compression can cause pseudo-obstruction of the bile duct. Use of both source and MIP reconstructed images obtained from different angles can help avoid cystic duct-related pitfalls. Repeat MRCP or conventional MR imaging can help avoid pitfalls related to the periampullary region. Segmental collapse of the normal main pancreatic duct may be misinterpreted as stenosis, but administration of secretin is helpful. An awareness of these pitfalls and possible solutions is crucial for avoiding misinterpretation of MRCP images.

Biliary Tract↗
PubMedDate not supplied

Small hepatocellular carcinoma with minute satellite nodules.

BACKGROUND/AIMS: To investigate the clinicopathologic characteristics of small hepatocellular carcinoma with minute satellite nodules. METHODOLOGY: We investigated the clinicopathologic characteristics of 131 solitary small (< or = 2.0 cm in diameter) hepatocellular carcinomas including 105 hepatocellular carcinomas without minute satellite nodules and 17 hepatocellular carcinomas with minute satellite nodules smaller than 5 mm, and also discuss the clinical significance. RESULTS: None of the clinical backgrounds of the patients and pathologic features of the main tumor, except for the average of preoperative serum alpha-fetoprotein, were significantly different between the two groups. Firstly, minute satellite nodules demonstrated that the maximum diameter of all minute satellite nodules was 1.5-4.0 mm, secondly, the moderately to poorly differentiated hepatocellular carcinomas had 4 or more minute satellite nodules within 1 cm from the main tumor, while well differentiated hepatocellular carcinomas may have 1 or 2 minute satellite nodules 6 cm or more away, and thirdly, 4 or more minute satellite nodules may present within 1 cm in intrahepatic metastasis cases, while 1 or 2 minute satellite nodules may be present 6 cm or more away from the main tumor in multicentric occurrence cases. CONCLUSIONS: At least 13% of solitary small hepatocellular carcinomas had preoperatively undetectable minute satellite nodules. In case of moderately to poorly differentiated hepatocellular carcinomas, hepatic resection as well as percutaneous ethanol injection should be performed including the surrounding liver tissue at least 1.0 cm from the main nodule. On the other hand, in well-differentiated hepatocellular carcinomas, which may indicate multicentric occurrence, closer observation and careful follow-up after therapy are recommended.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

[Activity of ATP-dependent protease and steroid metabolism in the human placenta].

Placenta play the important role of nourishment of fetus and for the regulation of fetal and maternal steroid metabolism. Steroid metabolism is synthesized in mitochondria and levels of enzymes in steroid metabolism are regulated by the rate of synthesis and degradation of these enzymes. Therefore, we studied protease in human placental mitochondria to clarify regulation mechanism of steroid-synthesizing enzymes. 50 micrograms of human early and term placenta homogenate, proteins were analyzed by immunoblotting technique after SDS-polyacrylamid gel electrophoresis. ATP-dependent protease was detected using antiserum raised against purified bovine adrenocortical ATP-dependent protease and avidin-biotin complex method. ATP-dependent protease activity was assayed using 14C-Caseins a substrate. Five cell fractions of homogenate placenta were electrophorated and antibody-stained using ATP-dependent protease, cytochrome P-450 scc and adrenodoxin antibody after the blotting, and the quantity was analyzed by the densitometry and the method of De Douve. We had the following results: 1) ATP dependent protease is present in human placenta and localized in mitochondria. 2) ATP dependent protease decomposes adrenodoxin reductase in human placenta. 3) ATP dependent protease present in almost same consistent in early and term placenta and there is no significant difference. It is suggested as follows that the ATP dependent protease in human placenta participates in the regulation of steroid hormone through the metabolism of steroid synthetic enzyme.

ATP-Dependent Proteases↗
PubMedDate not supplied

Diffusely calcified renal cell carcinoma: CT features.

Calcifications of renal masses are common. They are usually dense, partial, small, punctate, and linear opacities. Diffuse calcification is an extremely rare feature of renal masses. Generally, calcified renal cell carcinomas are hypovascular, with calcifications in the interstitium, and they also contain fibrotic capsules, necrotic areas, or hyalinization. We recently observed a renal neoplasm with diffuse calcification on CT and intermediate vascularity on angiography, which was diagnosed histologically as renal cell carcinoma, clear cell type. Interestingly, there were numerous calcific deposits within the tumor cells.

Adult↗
PubMedDate not supplied

MR imaging of human herpesvirus-6 encephalopathy after hematopoietic stem cell transplantation in adults.

BACKGROUND AND PURPOSE: Human herpesvirus-6 (HHV-6)-associated encephalopathy tends to develop in immunocompromised patients. Neurologic symptoms, such as disorientation, short-term memory loss, convulsion, coma, and hypopnea could occur, but they may be nonspecific. We retrospectively reviewed MR images of 6 adults with HHV-6-associated encephalopathy to study characteristic imaging findings that could be useful in making the diagnosis. MATERIALS AND METHODS: Between 2003 and 2005, we encountered 6 cases of HHV-6-associated encephalopathy (3 men and 3 women; age range, 36-55 years) in 3 hospitals. The diagnosis was made clinically according to the neurologic symptoms accompanied by high-level copies of HHV-6 DNA in CSF or peripheral blood by quantitative polymerase chain reaction without the detection of any other infectious pathogen. RESULTS: All 6 patients had abnormal hippocampus/amygdala findings on presentation, and no other regions were involved. In the early period (0-2 days from onset), abnormal high signal intensity on fluid-attenuated inversion recovery (FLAIR) imaging (2 of 3, 67%) and on diffusion-weighted images accompanied by apparent diffusion coefficient (ADC) reduction (2 of 2, 100%) were observed. In the middle period (3-30 days), abnormal low signal intensity on T1-weighted images (5 of 6, 83%) and abnormal high signal intensity on T2-weighted images (4 of 6, 67%) and FLAIR (5 of 6, 83%) were confirmed. In the late period (> 30 days), we saw the resolution of signal intensity abnormalities and the appearance of atrophic change (4 of 4, 100%) of the affected regions. CONCLUSION: HHV-6-associated encephalopathy in adults tends to affect the mesial temporal lobe. MR imaging is useful for detecting HHV-6 encephalopathy and distinguishing it from the other diseases of the central nervous system in immunocompromised patients.

Adult↗
PubMedDate not supplied

Limitation of CT in diagnosis of pancreatic cancer.

The differentiation of pancreatic abnormalities remains a problem. We analyzed the sensitivity and specificity of computed tomography (CT) in the diagnosis of pancreatic disease, using six radiologists who had less than six months' training in CT (resident level: inexperienced) and six who had more than 12 months' training (staff level: experienced) in order to clarify the difficulty with CT in the qualitative diagnosis of pancreatic cancer. We reviewed retrospectively 100 cases: 28 cases of pancreatic cancer, 15 of chronic pancreatitis, three of acute pancreatitis, 12 of neoplastic disease that involved the pancreas, and 42 normal subjects. The average sensitivity and specificity of CT in the diagnosis of pancreatic disease were 81.3% and 84.4%, respectively, for the experienced radiologists and 64.0% and 82.1%, respectively, for the inexperienced radiologists. The averages for pancreatic cancer were 65.3% and 87.8% for the experienced radiologists and 60.7% and 87.3% for the inexperienced radiologists. We conclude that the ability to detect pancreatic abnormalities improves with training and experience, but diagnosis of pancreatic cancer does not improve after a certain level of expertise.

Adult↗
PubMedDate not supplied

Chronic liver disease: value of volumetry of liver and spleen with computed tomography.

Volumetric comparisons of portions of liver and spleen were performed in patients with chronic liver diseases to determine their diagnostic value. Volumetric ratios of liver and spleen were determined by CT examination in 34 normal subjects and 125 consecutive patients with histologically proved liver cirrhosis, chronic active hepatitis, chronic persistent hepatitis, acute hepatitis, or fatty liver. Ratios of caudate lobe, spleen, and lateral segment of the left lobe of the liver to the remainder of the liver, right lobe and medial segment of the left lobe (RL+LM), were calculated. The product of caudate lobe/RL+LM and spleen/RL+LM was of value in differentiating liver cirrhosis from other liver disease, with a sensitivity of 60%, specificity of 98%, and accuracy of 86%. The same ratios differentiated liver cirrhosis and chronic active hepatitis from other liver diseases with a sensitivity of 79%, specificity of 100%, and accuracy of 90%. Volumetric ratio measurements are useful in the diagnosis of cirrhosis and chronic active hepatitis.

Acute Disease↗
PubMedDate not supplied

Computed tomography and histologic appearance of pancreatic metastases from distant sources.

The computed tomographic and histologic appearances in 34 cases of autopsy-confirmed metastatic tumors of the pancreas including secondary malignant lymphoma are discussed. In 18 (53.8%) the pancreas appeared abnormal on computed tomography, the lesions being classified into three types: In 8 cases there was diffuse enlargement of the pancreas; in 9 cases a localized mass; and one patient had multiple low attenuated nodules within the organ. Histologic investigation revealed that metastatic carcinoma involved the pancreatic lobules. The degree of infiltration in the interlobular connective tissue was related to the invasiveness of the tumors. In the majority of cases with diffuse infiltration the pancreatic lobules were destroyed and varying degrees of proliferation of malignant cells into the interlobular septa were documented. In patients with localized infiltration there was extensive invasion of the carcinoma within the pancreatic lobule. Dilatation of the pancreatic duct and/or organ-related symptoms were occasionally seen in these cases.

Adult↗
PubMedDate not supplied

Effects of ifenprodil tartrate on alpha-adrenoceptors and Ca2+ movement in isolated canine saphenous veins.

The effect of ifenprodil tartrate (IFT) on 2 subtypes of postsynaptic alpha 1- and alpha 2-adrenoceptors was investigated. For this purpose, changes in the tension of isolated canine saphenous veins were measured isometrically, and Ca2+ uptake in these veins was also measured. IFT displaced the dose-contractile response curves for phenylephrine and clonidine in a competitive manner, and the activity sequence of antagonists against phenylephrine was IFT greater than phentolamine greater than prazosin greater than yohimbine. On the other hand, the activity sequence of antagonists against clonidine was IFT greater than phentolamine greater than yohimbine greater than prazosin. The effect of IFT as well as that of phentolamine were different from the other antagonists and of approximately the same specific activities against both agonists. The IFT-induced relaxations of the veins contracted by phenylephrine and clonidine were relatively unchanged in both normal and Ca2+-free solutions. IFT inhibited phenylephrine- and clonidine-induced Ca2+ uptake in the saphenous veins. The results suggest that IFT does not possess a relative selectivity toward postsynaptic alpha 1- and alpha 2-adrenoceptors, and that these actions reflect the vasorelaxing effects on phenylephrine- and clonidine-induced contraction in the canine saphenous veins.

Adrenergic alpha-Antagonists↗
PubMedDate not supplied

Forty-eight hour liver preservation using an artificial blood substitute.

Forty-eight hour hypothermic continuous perfusion preservation was attempted using a perfusion technique with an artificial blood substitute, a pyridoxylated hemoglobin-polyoxyethylene conjugated solution (stabilized hemoglobin, PHP). After preservation each of the 10 canine livers was orthotopically transplanted. Postoperative graft function was estimated by parameters such as activated clotting time (ACT), bile excretion, consciousness level, survival period, histologic findings, and adenosine triphosphoric acid (ATP) content of the perfused liver. Four of ten livers displayed good function, with bile excreted immediately after revascularization, and animal survival for over 24 hr. Cellular structure of the liver was well maintained, although atrophy of the hepatocytes and swelling of the mitochondria were seen. PHP solution is therefore considered suitable as a perfusate for long-term liver preservation.

Animals↗
PubMedDate not supplied

Superiority of selective bolus infusion and simultaneous rapid removal of anticancer agents by charcoal hemoperfusion in cancer treatment.

This report presents the clinical effectiveness of multidisciplinary therapy consisting of intraarterial selective chemotherapy, combined with radiofrequency regional hyperthermia (RFRH) in advanced cancer patients. Patients were categorized into the following therapeutic groups: Group I: RFRH without intraarterial chemotherapy. Group II: Intraarterial infusion of a standard dose of Mitomycin C (MMC) and 5Fu. Group III: RFRH combined with intraarterial chemotherapy as in Group II. Group IV: RFRH combined with a large intraarterial infusion of MMC or Adriamycin (ADM) during charcoal hemoperfusion. Clinical effectiveness in terms of more than 50% tumor size reduction was achieved in 9% in Group I, 0% in Group II, 25% in Group III and 55% in Group IV, respectively. In Group IV, several side effects were observed but were not serious, despite the lethal dose of drug administered. These results suggest that RFRH combined with selective infusion chemotherapy, especially when large doses are administered during charcoal hemoperfusion, is a valuable treatment for advanced cancer patients.

Adolescent↗
PubMedDate not supplied

Computed tomography of accessory spleens.

Computed tomography's (CT) ability to detect accessory spleens was assessed using histopathologically proven cases. CT proved to be a sensitive procedure for detecting accessory spleens that were 10 mm or larger in diameter and located in the left upper quadrant.

Adolescent↗
PubMedDate not supplied

Hepatocellular carcinoma with pyrexia: report of a case.

Reported here is a case of an unusual type of hepatocellular carcinoma (HCC). Since this patient with liver mass exhibited continuous pyrexia, an inflammatory pseudotumor or abscess was strongly suspected. Two-phased incremental CT, MR with and without Gd-DTPA administration, and angiography demonstrated peripheral enhancement of the hepatic mass. Histologically, the tumor proved to be HCC with sarcomatoid degeneration. When one encounters a patient with a mass clinically and radiologically mimicking an inflammatory pseudotumor or an abscess, poorly differentiated HCC with sarcomatoid degeneration should be suspected.

Aged↗
PubMedDate not supplied

Well-differentiated hepatocellular carcinoma: isointense to liver parenchyma on superparamagnetic iron oxide-enhanced MR.

We present a patient with hepatocellular carcinoma that was identified on precontrast MR and became isointense to liver parenchyma after the intravenous administration of superparamagnetic iron oxide. The tumor was well-differentiated hepatocellular carcinoma and contained approximately the same number of Kupffer cells as liver parenchyma on pathological examination. Our case suggests that superparamagnetic iron oxide may give confusing results if the hepatic mass, e.g., hepatocellular carcinoma, contains Kupffer cells.

Carcinoma, Hepatocellular↗