Effects of ion exchange on the free volume and oxygen permeation in Nafion for fuel cells.

Variations of the free volume, O2 permeability, and structure of the Nafion membrane upon ion exchange of H+ with Na+ and K+ were studied. The free volume was quantified using the positron annihilation lifetime (PAL) technique, whereas the polymer structure was characterized by dynamic mechanical analysis (DMA), nanoindentation, and wide-angle X-ray diffraction (WAXD). It was found that the ion exchange significantly expands the free volume and at the same time decreases the O2 permeability. This is opposed to the simple free volume model in which the structure with less open volume is more amenable to lower permeability. Comparison of experimental data collected by different techniques revealed that not only the free volume but also the polymer stiffness plays an essential role in O2 permeation.

Radiation dose in mass screening for gastric cancer with high-concentration barium sulfate compared with moderate-concentration barium sulfate.

Recently, high-concentration barium sulfate has been developed and is used in many medical facilities. This study compared radiation dose using high-concentration and moderate-concentration barium sulfate. The dose was evaluated with an experimental method using a gastric phantom and with a clinical examination. In the former, the dose and X-ray tube load were measured on the phantom with two concentrations of barium sulfate. In the latter, the fluoroscopic dose-area product (DAP), the radiographic DAP and their sum, the total DAP, were investigated in 150 subjects (112 males, 38 females) treated with both concentrations of barium sulfate. The effective dose was calculated by the software of PCXMC in every case. The results of the experimental evaluation indicated that the effective dose and X-ray tube load were greater with high-concentration barium sulfate than with moderate-concentration barium sulfate (p < 0.05). The results of the clinical evaluation indicated that the fluoroscopic DAP was greater with moderate-concentration barium sulfate than with high-concentration barium sulfate (p < 0.05), but the radiographic DAP was quite the reverse, so the total DAP and effective dose were almost same with both concentrations of barium sulfate. We conclude that high-concentration barium sulfate does not increase radiation dose in mass screening for gastric cancer.

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.

Prospective and randomized trial of lipiodol-transcatheter arterial chemoembolization for treatment of hepatocellular carcinoma: a comparison of epirubicin and doxorubicin (second cooperative study). The Cooperative Study Group for Liver Cancer Treatment of Japan.

A randomized, controlled clinical trial was conducted to compare the use of epirubicin (EPI) and doxorubicin (DOX) in Lipiodol (Laboratoire Guerbet, Roissy-Charles-de-Gaulle Cedex, France)-transcatheter arterial chemoembolization as a treatment of hepatocellular carcinoma. One hundred ninety-two hospitals participated, and 415 patients were enrolled in the study during the period between October 1989 and December 1990. The patients were randomly allocated to group A (EPI) or group B (DOX) by a centralized telephone registration. The actual doses of EPI and DOX were 72 mg/body and 48 mg/body, respectively. The 1-, 2-, and 3-year survival rates were, respectively, 69%, 44%, and 33% for group A and 73%, 54%, and 37% for group B. There were no statistically significant differences (P = .2296, log-rank test). When each group of patients was classified retrospectively into high-risk and low-risk subgroups based on the severity index calculated by the Cox regression model from the significant prognostic factors (the pretreatment tumor size, the pretreatment serum alpha-fetoprotein level, tumor encroachment, and Child's classification), the survival curve of the low-risk DOX subgroup was significantly superior to that of the low-risk EPI subgroup (P = .0182). However, there was no significant difference between the high-risk subgroups (P = .4606). The change in the serum alpha-fetoprotein level, the extent of Lipiodol accumulation in the tumor, and the extent of tumor reduction after the treatment did not show any significant differences between the groups. The white blood cell count in group B showed a tendency to decrease slightly more than in group A at 3 weeks after Lipiodol-transcatheter arterial chemoembolization. In conclusion, there was no statistically significant difference between the survival curves of the EPI and DOX groups in Lipiodol-transcatheter arterial embolization treatment of hepatocellular carcinoma.

Needle tract implantation of hepatocellular carcinoma after percutaneous liver biopsy.

The authors report a case of needle tract implantation of hepatocellular carcinoma following percutaneous biopsy of the liver. The patient, a 62-year-old Japanese male, was found to have a small hepatocellular carcinoma diagnosed by needle biopsy; this was followed by transcatheter chemoembolization, a combination of transcatheter arterial infusion of adriamycin and transcatheter arterial embolization of Gelfoam, and right lobectomy. Eight months after the biopsy and the lobectomy, a nodule of hepatocellular carcinoma, measuring 3.5 cm in diameter, was found at the site of the previous biopsy and excised. The patient is doing well without further recurrence of tumor 23 months after the lobectomy and 15 months after the excision of the implanted tumor in the subcutis.

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.

Clinical features of small hepatocellular carcinomas as assessed by histologic grades.

BACKGROUND: Ninety-seven patients with small hepatocellular carcinomas (HCCs) measuring 3 cm or less in size and three patients with adenomatous hyperplasia who underwent radical hepatic resection were examined in this study. METHODS: The lesions were classified into four groups according to the following histologic grading criteria: group A, adenomatous hyperplasia (n = 3); group B, early HCC (n = 6); group C, well-differentiated HCC (wHCC) (n = 32); and group D, moderately or poorly differentiated HCC (n = 59). The involvement factors that seemed to be important or to characterize the progression of HCC and the survival rates were compared among the four histologic groups. RESULTS: The frequency of patients with tumors larger than 2.0 cm in size and that of patients with 200 or more ng/ml serum alpha-fetoprotein increased with the progression of histologic malignancy. Tumor staining on the angiogram, capsular formation, and extranodular invasion were never seen in groups A and B, but they began to appear in group C and increased remarkably in group D. The 5-year survival rates of the patients in groups B, C, and D were 100%, 60%, and 27%, respectively, and statistically significant differences were seen among them. In comparative evaluation of the group C patients the lesions that showed no tumor staining had no capsule, and those that had no capsule had no extranodular invasion. The 5-year survival rate of patients with wHCC without extranodular invasion (81%) was significantly higher than that of patients with extranodular invasion (35%) (p < 0.05). CONCLUSIONS: It may be recommended to provide the category of wHCC without extranodular invasion for pathologic classification of clinically early HCC (i.e., HCC of high curability).

Pancreatic invasion as the prognostic indicator of duodenal adenocarcinoma treated by pancreatoduodenectomy plus extended lymphadenectomy.

UNLABELLED: Pancreatoduodenectomy has become the standard procedure in resection of the duodenal adenocarcinoma, and some adjuvant therapies can be added to obtain further improvement in postoperative outcome. However, for patient selection, it is necessary to have a predictive indicator showing, if possible before laparotomy, which instances are noncurable by surgery alone or need adjuvant therapies. METHODS: A retrospective analysis was made for 24 consecutive patients whose duodenal adenocarcinoma were treated by pancreatoduodenectomy plus a wide range of lymphadenectomies without any adjuvant therapies at Osaka Medical Center for Cancer and Cardiovascular Diseases. Patient survival rates were related to macroscopic and microscopic findings and to findings obtained by preoperative imaging techniques. RESULTS: The overall survival rate was 69% at 3 years and 57% at 5 years; locoregional recurrence was the primary cause of death. Although the 5-year survival rate was 44% in patients with nodal involvement and 76% in those without, this difference did not reach statistical significance (P = .079). Instead, invasion into the pancreatic parenchyma at a macroscopic level was the most significant prognostic factor; the 5-year survival rate was 78% in the 16 patients without and 16% in the 8 patients with pancreatic invasion (P = .0047). Invasion into the pancreas correlated well with the angiographic findings; the 5-year survival rate was 25% in patients whose angiograms delineated the pancreatic invasion and 83% in patients whose angiograms did not (P = .0084). CONCLUSION: When duodenal adenocarcinoma was treated by pancreatoduodenectomy plus a wide range of lymphadenectomy, pancreatic invasion at a macroscopic level was most associated with patient survival. Pancreatic invasion was well delineated by the preoperative angiogram, which would be helpful in patient selection.

Hemobilia after percutaneous transhepatic biliary drainage.

Hemobilia after the inception of percutaneous transhepatic biliary drainage (PTBD) has been reported as an uncommon, but sometimes fatal, complication. We examined the incidence, pathogenesis, and management of hemobilia in 94 patients who received PTBD. There were seven cases (7.4%) with transient and six (6.4%) with severe hemobilia; one patient (1.1%) of the latter group died. There was no correlation between hemobilia and hemostatic or hepatic insufficiency. Angiography during PTBD was performed in 47 patients, and abnormalities restricted to arterial changes were noted in nine (19.1%). All but one patient with hemobilia showed angiographic abnormalities. Our findings indicate that hemobilia occurs more often than has been suspected and that it is usually due to intrahepatic vessel injury rather than to hemorrhagic diathesis or hepatic insufficiency. The primary management of hemobilia consists of maintaining continuous patency of the drainage catheter.

Hepatocellular carcinoma in adenomatous hyperplasia of the liver.

A hepatocellular carcinoma (HCC) measuring 0.2 cm in diameter was found in the center of an adenomatous hyperplasia (AH) measuring 1.7 cm in diameter in a cirrhotic liver. The liver cells of the AH showed a marked fatty change and contained many Mallory bodies. The AH and HCC were studied in relation to liver cell dysplasia in 108 surgically resected livers. The AH was mainly associated with fully developed cirrhosis in 5 (71%) of the 7 cases. The liver cell dysplasia, however was accompanied largely by fibrosis and early-stage incomplete septal cirrhosis in 10 (67%) of the 15 cases. As far as the active inflammatory change was concerned, a fairly active inflammation was found in only 3 (20%) of the 15 livers with liver cell dysplasia, but in 4 (57%) of the 7 livers with AH.

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.

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.

Selection of therapeutic modalities for hepatocellular carcinoma in patients with multiple hepatic lesions.

In the present study, we compared the survival of patients with multi tumor hepatocellular carcinoma (HCC) following their treatment with liver resection versus TAE. A total of 336 HCC patients were treated at Osaka University Hospital between 1980 and 1989. Of these, 140 patients underwent liver resection in the presence or absence of TAE and 173 subjects were treated with TAE alone. Our TAE protocol consisted of 50 mg Adriamycin, 3-5 ml lipiodol, and Gelfoam. The 1-, 3-, and 5-year survival values found for the liver resection group were 87.4%, 66.0%, and 47.4%, respectively, whereas the values calculated for the TAE group were 64.6%, 29.9%, and 15.8%, respectively. The survival of patients in the resection group was clearly better than that of subjects in the TAE group. Of the 140 patients who underwent resection, 36 cases were proven to have multiple lesions by histopathological examination. The 1- and 3-year survival values determined for this special group were 67.9% and 33.3%, respectively. Of the TAE cases, 113 were diagnosed as having multiple lesions by imaging examination, and their 1- and 3-year survival values were 59.7% and 24.9%, respectively. No significant differences in survival was found between these two different treatment modalities for these multiple-lesion cases. The results of this study indicate that it is unlikely that surgical resection is superior to TAE alone for the treatment of HCC patients with multiple lesions.

Effectiveness of Lipiodol in transcatheter arterial embolization of hepatocellular carcinoma.

The effectiveness of Lipiodol (iodized oil) in transcatheter arterial embolization (TAE) of hepatocellular carcinoma (HCC) was retrospectively evaluated using statistical analysis. A total of 343 HCC patients who underwent TAE at 5 institutions between 1984 and 1989 were divided into 2 groups: the GS-TAE group underwent TAE with Gelfoam sponge alone, whereas the LP-TAE group was given Lipiodol (LP) immediately before GS-TAE. The statistical T value calculated for the LP-TAE group showed that the administration of LP, the tumor size, intrahepatic metastasis, portal vein infiltration, and serum total bilirubin and alpha-fetoprotein levels significantly (P < 0.01) affected the patients' survival. Both the cumulative survival determined using the Kaplan-Meier model and the cumulative hazard calculated using Cox's proportional hazard model differed significantly (P < 0.01) between the GS-TAE group and the LP-TAE group (log-rank test). These results confirmed the effectiveness of LP used in combination with Gelfoam sponge for TAE of HCC.

Significance of transcatheter chemoembolization combined with surgical resection for hepatocellular carcinomas.

In order to improve the survival rate after liver resection for hepatocellular carcinoma (HCC), 71 HCC patients were treated with transcatheter chemoembolization (TCE). In the present study, we analyzed the effects of TCE on the patients' survival rates, as well as on the liver specimens resected in a histopathological study, comparing those not treated with TCE (n = 21). The overall survival rates, including hospital mortality, for 1 year, 3 years and 5 years were 81%, 72% and 54% respectively. However, no differences were observed in the survival rates between the TCE and the non-TCE groups. A histopathological study demonstrated that TCE was quite effective on the main tumor but not on intrahepatic metastasis or on tumor thrombus in the portal vein. However, we found that most of the intrahepatic metastatic lesions were necrotized in 8 of the 30 cases with these lesions. The histopathological study proved that these particular cases had some abnormalities in the portal blood supply. All but one of them are currently alive 3-48 months after resection, although the prognosis of the patients who had intrahepatic metastasis or a tumor thrombus in the portal vein was extremely poor. Preoperative TCE may, therefore, be thought of as a useful modality when it is effective in killing intrahepatic metastases. To control the lesions, portal vein embolization may be a promising technique in the future.

Development and aging of the cerebrum: assessment with proton MR spectroscopy.

BACKGROUND AND PURPOSE: MR spectroscopy allows the noninvasive evaluation of in vivo brain metabolites. Our purpose was to use this technique to assess metabolic alterations in the human cerebrum during growth, maturation, and aging. METHODS: Ninety normal human brains in subjects aged 4 to 88 years were examined with multivoxel proton MR spectroscopy. Spectra were obtained from specific voxels of 2.5 cm3 in the gray and white matter of the centrum semiovale. The ratios of N-acetylaspartate (NAA) to choline (Cho) were calculated to describe age-dependent alterations in cerebral metabolites. RESULTS: White matter NAA/Cho ratios showed rapid growth during the first decade and reached a maximum value in the second or early third decade, followed by a steady decline starting in the latter half of the third decade. The maximum peak ages for NAA/Cho were 21.9, 17.6, and 15.9 years (mean, 18.5 years) for the anterior, middle, and posterior white matter, respectively. A significant cerebral laterality of the white matter NAA/Cho was found in male subjects during development. The growth spurt and age-related decline of the white matter NAA/Cho were steeper in male than in female subjects. In contrast, the gray matter NAA/Cho showed a gradual decline with age. CONCLUSION: Proton MR spectroscopy shows significant regional and sex differences in the level of cerebral metabolites during the process of growth, maturation, and aging. This technique may play an important role in clinical applications for various conditions of metabolic disorders of the human brain.

MR of xanthogranuloma of the choroid plexus.

We present a case of a xanthogranuloma of the lateral ventricle choroid plexus in association with focal areas of abnormal T2 signal in the tegmentum of the pons as well as within the middle cerebellar peduncles. The characteristic MR appearance of this rare entity is described along with a pathologic basis suggesting an association with posterior fossa lesions.

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.

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.

Quantification of interstitial lung abnormalities with chest radiography: comparison of radiographic index and fractal dimension.

RATIONALE AND OBJECTIVES: The authors performed this study to evaluate two physical measures used for quantifying interstitial lung abnormalities on chest radiographs: the normalized radiographic index (RI) and the fractal dimension (FD). MATERIALS AND METHODS: The RI and FD were obtained from 50 regions of interest (ROIs) in lungs with mild interstitial abnormalities, 50 ROIs in lungs with severe interstitial abnormalities, and 50 ROIs in normal lungs. The RI was defined as the normalized percentage area of extracted opacities in selected ROIs. FD was calculated with a box-counting algorithm. To extract linear opacities selectively, the authors processed ROIs with four-directional Laplacian-Gaussian filtering and binarization, linear opacity judgment (LOJ), and linear opacity subtraction (LOS). The usefulness of the physical measures for quantifying interstitial lung abnormalities was evaluated with receiver operating characteristic analysis. RESULTS: In normal and mild abnormality groups, observer performance with the RI was worse with LOJ images (area under the receiver operating characteristic curve [Az] = .812 +/- .042) than with LOS images (Az = .912 +/- .028, P < .05), and performance with FD was better with LOJ images (Az = .867 +/- .037) than with LOS images (Az = .750 +/- .048, P < .05). In the normal and severe abnormality groups, performance with RI and FD was better with LOJ images (RI: Az = .992 +/- .007; FD: Az = .968 +/- .016) than with LOS images (RI: Az = .883 +/- .034, P < .001; FD: Az = .767 +/- .047, P < .0001). CONCLUSION: The RI is considered to reflect the sensitivity in the detection of interstitial lung abnormalities on chest radiographs. Conversely, the FD is considered to reflect specifically the linear opacities processed with LOJ.