Therapeutic efficacy of transcatheter arterial chemoembolization for hepatocellular carcinoma: MRI and pathology

OBJECTIVE

Our goal was to evaluate the usefulness of multisection dynamic MRI with gadopentetate dimeglumine in the assessment of the therapeutic efficacy of transcatheter arterial chemoembolization (TAE) with iodized oil for hepatocellular carcinomas (HCCs).

MATERIALS AND METHODS

Findings on multisection dynamic MRI images were compared with gross appearance and histologic findings in 13 patients with HCCs after TAE with iodized oil. Arterial dominant phase images of the entire liver were obtained 20 s after the start of administration of gadopentetate dimeglumine.

RESULTS

In 3 of the 13 patients, no enhancing areas within the tumors were detected. In the remaining 10 patients, enhancing portions were detected within the tumor on arterial dominant phase images. Histologically, viable tumor cells were present in the rapidly enhancing portions, while necrotic tissues were present in nonenhancing areas, irrespective of the accumulation of iodized oil on CT scans. However, in one patient in whom no enhancing portion was seen in the tumor, a small number of viable tumor cells within the capsule were identified on pathologic examination.

CONCLUSION

Multisection dynamic MRI is helpful for evaluating the therapeutic efficacy of TAE with iodized oil for HCCs by revealing the hemodynamics of the tumor irrespective of accumulation of iodized oil.

Structure-activity relationships of alkylamines that inhibit rat liver hydroxysteroid sulfotransferase activities in vitro

Tetraalkylammonium salts having n-propyl to n-amyl side chains inhibited rat liver sulfotransferase (ST) activities toward dehydroepiandrosterone and cortisol, but not ST activity toward 2-naphthol, whereas trialkylamines having ethyl to n-amyl side chains inhibited ST activity toward dehydroepiandrosterone, but not ST activities toward cortisol and 2-naphthol. A comparison of I50 values, which represent inhibitor concentration resulting in 50% inhibition of dehydroepiandrosterone ST activity, revealed that the values for the tetraalkylammonium salts were 0.015 to 0.017 mM, whereas the values for the trialkylamines were 0.20 to 0.33 mM. Introduction of hydrophilic groups such as hydroxyl, thiol, nitrile and acetamide groups or substitution by methyl and allyl groups in the alkyl side chains markedly diminished the inhibitory effect of triethylamine. These data indicate that ethyl to n-amyl side chains are a prerequisite for the alkylamine-type inhibitor. Tertiary amine drugs such as imipramine, dimenhydrinate, cyclizine, chlorpromazine and promethazine inhibited ST activities toward dehydroepiandrosterone and cortisol similar to the tetraalkylammonium salts, although the drugs were weaker inhibitors of hydroxysteroid ST activities. These results imply that in addition to trialkylamine side chains, the other portion of the drugs may participate in the inhibition of hydroxysteroid ST activities.

Unruptured interstitial pregnancy: a pitfall of MR imaging

We report two cases with interstitial pregnancy, which showed completely different MR appearances. In case 1, a gestational sac was demonstrated and the diagnosis of ectopic pregnancy was straightforward. In case 2, a hypervascular mass was shown without demonstration of a gestational sac, the findings usually seen in gestational trophoblastic disease (GTD). MR imaging may play some role in the diagnosis of interstitial pregnancy when sonography is insufficient or equivocal. If GS is visualized, diagnosis is easy. However, if not, the appearance may have a spectrum and can be similar to GTD.

Phenotypic instability of transgenic tobacco plants and their progenies expressing Arabidopsis thaliana small GTP-binding protein genes

Chimeric genes consisting of the cauliflower mosaic virus 35S promoter, a cDNA encoding a small GTP-binding protein from Arabidopsis thaliana (ara-2 or ara-4) and the terminator of the nopaline synthase gene were cloned into a binary vector. Tobacco leaf tissues were transformed with this plasmid via Agrobacterium-mediated transformation. Transgenic plants possessing either ara-2 or ara-4 occasionally showed morphological abnormalities in leaves and other organs. However, such alterations were not always associated with co-transferred characters, such as kanamycin tolerance, and they arose in no more than 10% of the transgenic plants. Such phenomena were also observed in the progenies of the primary transgenic plants. Despite such unusual inheritance of the phenotypic abnormalities, GTP-binding activity of the inserted ara gene products was detected in all plants tested.

Genetic evidence for difference between intracellular and extracellular peptides in influenza A matrix peptide-specific CTL recognition

During the course of extensive mutagenesis of HLA-A2.1, we examined influenza A matrix peptide (FMP)-specific CTL recognition of HMy2.C1R (C1R) cells expressing mutant HLA-A2.1 molecules, sensitized with synthetic peptide, FMP 58-66, (exogenous peptide), or infected with influenza A virus (endogenous peptide). Most mutants showed equivalent presentation of exogenous and endogenous peptides to FMP-specific CTL. However, five of the mutants differed in this property. Two of the five mutants, F9L and T134K, present exogenous peptide to FMP-specific CTL, but fail to present endogenous peptide to CTL. Western blot analysis using anti-matrix protein Ab indicates that the matrix protein is expressed in these mutants after infection with virus. Interestingly, transfection of these two mutants with a minigene encoding FMP 58-66 results in efficient lysis by FMP-specific CTL. Peptide-binding assays demonstrate that the two mutations dramatically decrease the binding of FMP. However, these mutants bind FMP as well as wild type in the presence of exogenously added human beta 2-m, suggesting that the lower affinity for beta 2-m leads to the inability to present endogenous peptide. The remaining three mutants, Y27N, Q32K, and S132C, fail to present exogenous peptide, but present endogenous peptide to FMP-specific CTL. Pulse-chase analyses followed by endoglycosidase-H treatment show that the rate of maturation and processing of the five mutant HLA-A2 molecules in C1R cells is identical to that of wild type. Overall, this study suggests that the assembly and subsequent recognition of endogenous peptide differs from that of exogenous peptide.

Genetic evidence for difference between intracellular and extracellular peptides in influenza A matrix peptide-specific CTL recognition

During the course of extensive mutagenesis of HLA-A2.1, we examined influenza A matrix peptide (FMP)-specific CTL recognition of HMy2.C1R (C1R) cells expressing mutant HLA-A2.1 molecules, sensitized with synthetic peptide, FMP 58-66, (exogenous peptide), or infected with influenza A virus (endogenous peptide). Most mutants showed equivalent presentation of exogenous and endogenous peptides to FMP-specific CTL. However, five of the mutants differed in this property. Two of the five mutants, F9L and T134K, present exogenous peptide to FMP-specific CTL, but fail to present endogenous peptide to CTL. Western blot analysis using anti-matrix protein Ab indicates that the matrix protein is expressed in these mutants after infection with virus. Interestingly, transfection of these two mutants with a minigene encoding FMP 58-66 results in efficient lysis by FMP-specific CTL. Peptide-binding assays demonstrate that the two mutations dramatically decrease the binding of FMP. However, these mutants bind FMP as well as wild type in the presence of exogenously added human beta 2-m, suggesting that the lower affinity for beta 2-m leads to the inability to present endogenous peptide. The remaining three mutants, Y27N, Q32K, and S132C, fail to present exogenous peptide, but present endogenous peptide to FMP-specific CTL. Pulse-chase analyses followed by endoglycosidase-H treatment show that the rate of maturation and processing of the five mutant HLA-A2 molecules in C1R cells is identical to that of wild type. Overall, this study suggests that the assembly and subsequent recognition of endogenous peptide differs from that of exogenous peptide.

Structure of the mouse thioredoxin-encoding gene and its processed pseudogene

Thioredoxins (TXN) are small proteins with various biological functions, such as redox regulation, found in many species including bacteria, plants and animals. We previously reported the isolation of the TXN-encoding cDNAs from human and mouse. In order to elucidate the functions of the mammalian TXN system, we planned to generate Txn knockout mice, and cloned the genomic DNA fragments using the Txn cDNA as a probe. The Txn gene extends over 12 kb and consists of five exons separated by four introns. Detailed Southern analyses revealed that the mouse genome contains only one active Txn gene and one processed pseudogene (Txn-ps1), in contrast to some species which have families of active TXN-encoding genes. These findings should help to understand Txn itself, and provide a basis for transgenic experiments by gene targeting.

Asymmetry of the ventricle and age at the onset of schizophrenia

The relationship between lateral ventricular size or its asymmetry and age at the onset of schizophrenia was investigated in 20 schizophrenic patients diagnosed according to DSM-III-R criteria. The ventricle-brain ratio (VBR) was determined using three transaxial slices of magnetic resonance image (MRI) and asymmetry of the lateral ventricle was evaluated from the laterality index of the lateral ventricular area: (left-right/left+right) x 100. Each age at the onset of the prodromal and active phase according to DSM-III-R criteria was determined for each patient. The results showed that asymmetry of the ventricle, but not VBR, was significantly correlated inversely with age at the onset of both the prodromal phase and active phase. Neither asymmetry nor VBR correlated with the duration of illness, age at MRI scanning, or severity of clinical symptoms. It would thus appear that greater asymmetry of the ventricle is associated with earlier onset of schizophrenia.

Peripheral B lymphocyte repertoire to mitochondrial antigen in primary biliary cirrhosis--positive correlation between the disease activity and the frequency of circulating B lymphocytes specific for pyruvate dehydrogenase complex

B lymphocytes committed to the production of IgG antibodies (Abs) to mitochondrial antigen such as pyruvate dehydrogenase complex(PDC) were quantitated in the peripheral blood of patients with primary biliary cirrhosis(PBC) using Epstein-Barr virus as a polyclonal activator of human B lymphocytes. B lymphocytes committed to the production of IgG Abs to PDC were found in high frequency in patients with PBC(0.54 +/- 0.16%, mean value +/- SE, of total IgG-producing B lymphocytes) in contrast to type C chronic hepatitis and healthy subjects in which they were less than 0.01%. The frequency of these B lymphocytes specific for PDC increased in parallel to the progression of the Scheuer's stage from I to II (stage I: 0.35 +/- 0.23%, stage II: 1.04 +/- 0.32%), but decreased with further progression to stage IV (stage III: 0.39 +/- 0.21%, stage IV: 0.07 +/- 0.06%). In addition, B lymphocytes specific for PDC decreased in the peripheral blood during the administration of cyclosporin A; this was accompanied by an improvement of lymphocyte infiltration severity in the liver. These data indicate that B lymphocytes specific for PDC are present in the peripheral blood of patients with PBC and their frequency reflects the degree of the lymphocyte infiltration in the liver.

Impaired saccadic eye movements on stationary targets in patients with schizophrenia spectrum disorder

This study examined tracking eye movements on predetermined stationary targets in patients with schizophrenia spectrum disorder. The targets were 8 black points or 8 arabic-numbered points placed on the circumference of a circle. Self-paced eye movements during clockwise tracking of these points by 23 patients and 23 normal controls were recorded using an infrared eye-mark recorder. Eye movements were analyzed at two settings: firstly, when "fixation point" was defined as a point at which a gaze was held for at least 200-ms; and secondly, when held for at least 100-ms. The results indicated that at the 200-ms setting schizophrenic patients track with significantly fewer correct scores and more deviant scores than controls under black-point conditions. At the 100-ms setting, however, the correct scores of patients were not significantly different from those of controls, although patients displayed more aberrant paths than controls. The superfluous fixations in the patients improved significantly under numbered-point conditions, but patients still achieved lower correct scores than controls. Four of the 23 patients exhibited centering (aberrant path directed toward the center point), suggesting immature control of eye movements under black-point conditions, but not numbered-point conditions. These results suggest that some schizophrenic patients viewed the targets too quickly, and that they have impaired directed attention, which can be improved by cues, and may have impaired preprogramming of eye movements, which is not improved by external cues.

Assessment of MRI criteria for MS in Japanese MS and HAM/TSP

We evaluated the usefulness of the MRI criteria for multiple sclerosis (MS) proposed by Paty et al and Fazekas et al in 36 Japanese MS patients, using HTLV-I-associated myelopathy (HAM)/tropical spastic paraparesis (TSP) as the control. Although 30 of 36 HAM/TSP patients had multiple white matter lesions on T2-weighted cranial MRI, only two fulfilled the MRI criteria for MS. At the same time, 31 of the 36 MS patients fulfilled the primary MRI criterion, yielding 93% specificity and 86% sensitivity for the criterion. MS has disease-specific MRI abnormalities.

Use of monoclonal antibody to detect bone morphogenetic protein-4 (BMP-4)

A monoclonal antibody that reacts with murine and human bone morphogenetic protein-4 (BMP-4) has been developed using recombinant BMP-4 as an immunogen. The antibody that bound most tightly to recombinant murine (rm)BMP-4 was selected, subcloned, and characterized. The specificity of the antibody was confirmed using Western blot analysis and enzyme-linked immunosorbent assay (ELISA). The antibody reacts with murine and human BMP-4 in both the reduced and nonreduced condition; however, this antibody shows cross-reactivity with neither human BMP-2 nor TGF-beta 1. Thus, the produced antibody could recognize the disulfide-linked dimeric structure of bioactive BMP-4, regardless of the species. Immunocytochemical study using this antibody successfully shows the cytosolic localization of BMP-4 in osteoinductive cells; i.e., BFO and Saos-2 in which the level of mRNA for BMP-4 was proved to be constitutively high by Northern blot analysis. In addition, the antibody could demonstrate the presence of BMP-4 in developmental bone formation in the alveolar bone of rat embryo by immunohistochemistry. The antibody could be used for a more sensitive approach for quantitative analysis of BMP-4.

Mapping of rat bilirubin UDP-glucuronosyl-transferase gene (Ugt1a1) to chromosome region 9q35-->q36

Bilirubin and phenol UDP-glucuronosyltransferases (UGTs) are located on the same chromosome and comprise the UGT1 gene complex. A 1,763-bp cDNA probe (UGT1*0) specific for rat liver bilirubin UGT was used to localize the UGT1 complex locus (Ugt1a1) to chromosome region 9q35-->q36 by fluorescence in situ hybridization. This assignment is the first report on the location of a gene of the rat UGT1 complex using high-resolution banded metaphase chromosomes.

Clinical symptoms and regional cerebral blood flow in schizophrenia

This study examined the relationship between clinical symptoms and regional cerebral blood flow (rCBF) in schizophrenic patients using single photon emission computed tomography (SPECT). The subjects were 26 medicated schizophrenic patients diagnosed according to DSM-III-R criteria. Clinical symptoms were assessed using the Scale for the Assessment of Negative Symptoms (SANS), selected items for the Positive and Negative Syndrome Scale (PANSS), and the scale for Schneider's first rank symptoms. Resting rCBF was measured using N-isopropyl-p-[I-123] iodoamphetamine (I-123 IMP) SPECT, and relative rCBF distribution was evaluated in nine regions of interest in each hemisphere. Factor analysis of symptom ratings indicated four separate syndromes: psychomotor poverty, alienation (hallucination and disturbance of the self), delusion, and disorganization. Stepwise multiple regression analysis showed the psychomotor poverty syndrome to be correlated with decreased rCBF in bilateral superior frontal areas and increased rCBF in the left thalamus and right basal ganglia. The disorganization syndrome was correlated with increased rCBF in bilateral anterior cingulates and decreased rCBF in bilateral middle frontal areas. The alienation syndrome was shown related to increased rCBF in the right inferior frontal area and parietal area. Dysfunction in distinctive neural networks involving various prefrontal areas would thus appear to underlie these syndromes in schizophrenia.

Identification of novel CD23 transcripts on human T and B lymphocytes and eosinophil cell line

The main aim of the present studies was to investigate the structure of the human low-affinity IgE Fc receptor (CD23) present on T and B lymphoid cells and eosinophil cell line. A novel finding in these studies has been the detection and sequence analysis of CD23 transcripts in human T lymphocytes. These studies have established that some of the human T-cell populations analyzed express CD23 mRNA and that its structure is quite similar to that previously described for human B lymphocytes. A second major finding in these studies is that some human T- and B-cell lines and eosinophil cell line contain multiple forms of CD23 transcripts. These appear to be generated via alternative splicing, resulting in transcripts that may encode a truncated, possibly secretory form of CD23. These findings in human T and B lymphocytes and eosinophils provide new information about the structure of lymphocyte CD23 and suggest that alternative processing of transcripts generates CD23 mRNA that encodes CD23 isoforms. These studies are the first experimental evidence showing that CD23 isoforms may occur in the human and are the first direct evidence for production of CD23 by human T lymphocytes. In addition, these studies provide the first experimental evidence that T and B lymphocytes express CD23 transcripts lacking exon 3-encoded sequences, raising the possibility that a secretory form of CD23 may be synthesized by human T and B lymphocytes, and eosinophils.

Diurnal regulation of per repeat family in the suprachiasmatic nucleus of rat brain

We have recently reported fluctuations in the expression of the period repeat sequence, pp2.5, during light-dark cycles in the suprachiasmatic nucleus (SCN) of rat. Presently, we performed in situ hybridization which shows that the fluctuation of pp2.5 expression continues during constant darkness conditions in the SCN of rat. The light exposure during subjective night but not subjective day triggered its elevated expression in a time-dependent manner which is parallel to that of c-fos expression. In this review, the cloning and characterization of multiple per repeat sequences from mouse genom and rat brain mRNA were summarized. The abundance of a novel per repeat mRNA (designated as RB15) fluctuates during a light-dark cycle in the SCN. These findings suggest that per repeat sequence may have a role for the mammalian circadian rhythms. The evolutionary relationship between the mammarian per repeat sequence and the Drosophila period gene is also discussed.

In situ demonstration of the HTLV-I genome in the spinal cord of a patient with HTLV-I-associated myelopathy

Using polymerase chain reaction (PCR) and in situ hybridization, we investigated the HTLV-I genome in the CNS of an HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) patient with a 20-year disease duration. Neuropathologically, there was severe white matter degeneration throughout the spinal cord, but lymphocytic infiltrates were not evident in any lesion. PCR amplification of the pX region of HTLV-I DNA detected its sequence in the spinal cord and all extra-CNS tissue samples. In situ hybridization using probes complementary to the pX and gag regions detected the HTLV-I genome in the cytoplasm and nucleus of cells in the thoracic cord. The findings indicate a direct involvement of HTLV-I in the neurodegeneration of HAM/TSP.

[CD classification of lymphocytes and the function: significance of flow cytometric analysis in immunoneurological disorders]

We reviewed flow cytometric studies of lymphocyte subsets by using monoclonal antibodies in various immunoneurological disorders. In multiple sclerosis, most studies indicated decreases of suppressor T cells and suppressor-inducer T cells in both peripheral blood and cerebrospinal fluid (CSF). In HTLV-I-associated myelopathy, our studies showed an increase of CD28-negative cytotoxic T cells in the CSF, indicating the involvement of dysfunctioned cytotoxic T cells in the spinal cord lesion formation. In myasthenia gravis, the disease-specific finding is the appearance of CD4+ CD8+ (double positive) T cells in the peripheral blood, which may be associated with thymic abnormalities. These flow cytometric studies in immunoneurological disorders thus provide an insight in the pathogenesis of immunoneurological disorders.

[Gut mucosal immunity and oral tolerance]

The biological phenomenon that experimental animals become hyporesponsive to a particular protein antigen, when orally administered, is called oral tolerance. A breakdown of oral tolerance to dietary antigens may be related to food allergy. Conversely, the induction of oral tolerance by feeding autoantigens, such as myelin basic protein, protects animals from subsequent immunization by this antigen resulting in development of experimental autoimmune encephalomyelitis, which is a disease model of the human demyelinating disease, multiple sclerosis (MS). The mechanism of oral tolerance could be an induction of suppressor cells, which release inhibitory cytokines including transforming growth factor beta, when triggered antigen-specifically and/or clonal anergy to fed antigen. Against this background, patients with MS and rheumatoid arthritis are on a clinical trial with bovine myelin and type II collagen feeding, respectively. Oral tolerance could be a part of the mainstream in future treatment strategies for human diseases with autoimmune etiologies.

[High-resolution MR imaging of the mediastinum and hilus of the lung using surface-coils]

High-resolution MR imaging using surface-coils (Helmholtz-coil) was performed on patients with hilar lung cancer and healthy volunteers. We evaluated the clinical usefulness of this technique compared with MR imaging performed with a conventional body-coil. Although the signal-to-noise ratio was slightly decreased, normal anatomic structures, hilar masses, and enlarged lymph nodes were distinctly visualized in comparison with those on MR images obtained with a body-coil. High-resolution MR imaging with the Helmholtz-coil seemed to be useful for the evaluation of mediastinal and hilar disease, and may able to supplant MR imaging with a conventional body-coil in routine examinations.

Significance of the six peptide-binding pockets of HLA-A2.1 in influenza A matrix peptide-specific cytotoxic T-lymphocyte reactivity

To evaluate the roles of the six peptide-binding pockets of HLA-A2.1 in FMP-specific CTL recognition, we have constructed an extensive library of HMy2.C1R cell lines expressing mutant HLA-A2.1 molecules with different amino acid substitutions in each of the six pockets. These cell lines were tested for their ability to present synthetic FMP 58-66 to FMP-specific, HLA-A2.1-restricted human CTL lines. Six of 12 mutants with amino acid changes in pocket B significantly affect the FMP-specific CTL recognition, suggesting that pocket B plays a critical role in FMP-specific CTL recognition. Surprisingly, mutations in all other pockets, except for pocket F, also have significant effects on the CTL recognition. These results suggest that even the shallow pockets, which are likely to be less critical for peptide binding than the deep pockets, play a crucial role in FMP-specific CTL recognition.

Biochemistry and molecular biology of drug-metabolizing sulfotransferase

Sulfation is an important conjugation reaction in the metabolism of various xenobiotics and endogenous compounds and is catalyzed by sulfotransferase (ST) present in cytosols. The cloning studies on STs have provided the basis for the understanding of the ST multigene family. STs are classified into hydroxysteroid (or alcohol), aryl (or phenol), estrogen, flavonol and polysaccharide STs and recent developments in the molecular characterization of these isoforms are reviewed. Regulation and localization of ST isoforms in various tissues are characterized at the molecular level by virtue of the specific antibodies and the corresponding cDNA probes. The recent developments are summarized. ST inhibitors are potent tools for the study on ST multiplicity and for the characterization of the enzyme structure. It also appears to be important to understand exogenous and endogenous ST inhibitors in clinical environment. The recent developments are reviewed.

Estimation of phylogenetic relationships among Japanese brown frogs from mitochondrial cytochrome b gene (Amphibia: Anura)

We investigated phylogenetic relationships among five species of Japanese brown frogs by the analysis of nucleotide sequences in the cytochrome b gene of mitochondrial DNA (mtDNA). The sequence of the 251-base pairs, which cover approximately 22% of the cytochrome b gene, was determined by PCR-Direct sequencing method. Phylogenetic relationships were analyzed by UPGMA, neighbor-joining, maximum-likelihood, and maximum parsimony analyses. The sequences only slightly varied within one population of Rana japonica. Intraspecific variation in sequences varied among species, and R. tagoi showed more pronounced variation than did R. ornativentris. Rana japonica and R. tagoi share 2n = 26 chromosomes with each other, but the former was closer to R. pirica and R. ornativentris, both with 2n = 24, than to the latter. Phylogenetic relationships estimated from the nucleotide sequence of the cytochrome b gene generally conformed to the idea hitherto proposed chiefly on the bases of morphological and ecological evidences.