Inhibition promotes long-term potentiation at cerebellar excitatory synapses.

The ability of the cerebellar cortex to learn from experience ensures the accuracy of movements and reflex adaptation, processes which require long-term plasticity at granule cell (GC) to Purkinje neuron (PN) excitatory synapses. PNs also receive GABAergic inhibitory inputs via GCs activation of interneurons; despite the involvement of inhibition in motor learning, its role in long-term plasticity is poorly characterized. Here we reveal a functional coupling between ionotropic GABAA receptors and low threshold CaV3 calcium channels in PNs that sustains calcium influx and promotes long-term potentiation (LTP) at GC to PN synapses. High frequency stimulation induces LTP at GC to PN synapses and CaV3-mediated calcium influx provided that inhibition is intact; LTP is mGluR1, intracellular calcium store and CaV3 dependent. LTP is impaired in CaV3.1 knockout mice but it is nevertheless recovered by strengthening inhibitory transmission onto PNs; promoting a stronger hyperpolarization via GABAA receptor activation leads to an enhanced availability of an alternative Purkinje-expressed CaV3 isoform compensating for the lack of CaV3.1 and restoring LTP. Accordingly, a stronger hyperpolarization also restores CaV3-mediated calcium influx in PNs from CaV3.1 knockout mice. We conclude that by favoring CaV3 channels availability inhibition promotes LTP at cerebellar excitatory synapses.

Transient expression of neuropeptide W in postnatal mouse hypothalamus--a putative regulator of energy homeostasis.

Neuropeptide B and W (NPB and NPW) are cognate peptide ligands for NPBWR1 (GPR7), a G protein-coupled receptor. In rodents, they have been implicated in the regulation of energy homeostasis, neuroendocrine/autonomic responses, and social interactions. Although localization of these peptides and their receptors in adult rodent brain has been well documented, their expression in mouse brain during development is unknown. Here we demonstrate the transient expression of NPW mRNA in the dorsomedial hypothalamus (DMH) of postnatal mouse brain and its co-localization with neuropeptide Y (NPY) mRNA. Neurons expressing both NPW and NPY mRNAs begin to emerge in the DMH at about postnatal day 0 (P-0) through P-3. Their expression is highest around P-14, declines after P-21, and by P-28 only a faint expression of NPW and NPY mRNA remains. In P-18 brains, we detected NPW neurons in the region spanning the subincertal nucleus (SubI), the lateral hypothalamic (LH) perifornical (PF) areas, and the DMH, where the highest expression of NPW mRNA was observed. The majority of these postnatal hypothalamic NPW neurons co-express NPY mRNA. A cross of NPW-iCre knock-in mice with a Cre-dependent tdTomato reporter line revealed that more than half of the reporter-positive neurons in the adult DMH, which mature from the transiently NPW-expressing neurons, are sensitive to peripherally administrated leptin. These data suggest that the DMH neurons that transiently co-express NPW and NPY in the peri-weaning period might play a role in regulating energy homeostasis during postnatal development.

Complementary synaptic distribution of enzymes responsible for synthesis and inactivation of the endocannabinoid 2-arachidonoylglycerol in the human hippocampus.

Clinical and experimental evidence demonstrates that endocannabinoids play either beneficial or adverse roles in many neurological and psychiatric disorders. Their medical significance may be best explained by the emerging concept that endocannabinoids are essential modulators of synaptic transmission throughout the central nervous system. However, the precise molecular architecture of the endocannabinoid signaling machinery in the human brain remains elusive. To address this issue, we investigated the synaptic distribution of metabolic enzymes for the most abundant endocannabinoid molecule, 2-arachidonoylglycerol (2-AG), in the postmortem human hippocampus. Immunostaining for diacylglycerol lipase-α (DGL-α), the main synthesizing enzyme of 2-AG, resulted in a laminar pattern corresponding to the termination zones of glutamatergic pathways. The highest density of DGL-α-immunostaining was observed in strata radiatum and oriens of the cornu ammonis and in the inner third of stratum moleculare of the dentate gyrus. At higher magnification, DGL-α-immunopositive puncta were distributed throughout the neuropil outlining the immunonegative main dendrites of pyramidal and granule cells. Electron microscopic analysis revealed that this pattern was due to the accumulation of DGL-α in dendritic spine heads. Similar DGL-α-immunostaining pattern was also found in hippocampi of wild-type, but not of DGL-α knockout mice. Using two independent antibodies developed against monoacylglycerol lipase (MGL), the predominant enzyme inactivating 2-AG, immunostaining also revealed a laminar and punctate staining pattern. However, as observed previously in rodent hippocampus, MGL was enriched in axon terminals instead of postsynaptic structures at the ultrastructural level. Taken together, these findings demonstrate the post- and presynaptic segregation of primary enzymes responsible for synthesis and elimination of 2-AG, respectively, in the human hippocampus. Thus, molecular architecture of the endocannabinoid signaling machinery supports retrograde regulation of synaptic activity, and its similar blueprint in rodents and humans further indicates that 2-AG's physiological role as a negative feed-back signal is an evolutionarily conserved feature of excitatory synapses.

Pathologic and immunologic profiles of a limited form of neuromyelitis optica with myelitis.

BACKGROUND: Neuromyelitis optica (NMO) is a demyelinating syndrome characterized by myelitis and optic neuritis. Detection of anti-NMO immunoglobulin G antibody that binds to aquaporin-4 (AQP4) water channels allows the diagnosis of a limited form of NMO in the early stage with myelitis, but not optic neuritis. However, the detailed clinicopathologic features and long-term course of this limited form remain elusive. METHODS: We investigated 8 patients with the limited form of NMO with myelitis in comparison with 9 patients with the definite form. RESULT: All patients with limited and definite form showed uniform relapsing-remitting courses, with no secondary progressive courses. Pathologic findings of biopsy specimens from the limited form were identical to those of autopsy from the definite form, demonstrating extremely active demyelination of plaques, extensive loss of AQP4 immunoreactivity in plaques, and diffuse infiltration by macrophages containing myelin basic proteins with thickened hyalinized blood vessels. Moreover, the definite form at the nadir of relapses displayed significantly higher amounts of the inflammatory cytokines interleukin (IL)-1beta and IL-6 in CSF than the limited form and multiple sclerosis. CONCLUSION: This consistency of pathologic findings and uniformity of courses indicates that aquaporin 4-specific autoantibodies as the initiator of the neuromyelitis optica (NMO) lesion consistently play an important common role in the pathogenicity through the entire course, consisting of both limited and definite forms, and NMO continuously displays homogeneity of pathogenic effector immune mechanisms through terminal stages, whereas multiple sclerosis should be recognized as the heterogeneous 2-stage disease that could switch from inflammatory to degenerative phase. This report is a significant description comparing the pathologic and immunologic data of limited NMO with those of definite NMO.

Identification of binding sites for anti-aquaporin 4 antibodies in patients with neuromyelitis optica.

OBJECTIVE: Anti-aquaporin 4 antibodies (AQP4-Ab) are specifically detected in patients with neuromyelitis optica. To investigate the role of AQP4-Ab, we examined the antibody binding epitope using human and mouse mutant AQP4. METHODS: We constructed human and mouse amino acid substitution AQP4 mutants and compared the reactivity with wild-form of human, mouse and rat AQP4. RESULTS: The decreased intensity of AQP4-Ab staining with mouse AQP4 was recovered to that of human AQP4 with the mouse mutant A228E for 9 of the 10 sera. CONCLUSIONS: The third extracellular loop of AQP4 is considered to be the major epitope for AQP4-Ab in NMO.

Influence of parallel fiber-Purkinje cell synapse formation on postnatal development of climbing fiber-Purkinje cell synapses in the cerebellum.

The climbing fiber (CF) to Purkinje cell (PC) synapse in the cerebellum provides an ideal model for the study of developmental rearrangements of neural circuits. At birth, each PC is innervated by multiple CFs. These surplus CFs are eliminated during postnatal development, and mono innervation is attained by postnatal day 20 (P20) in mice. Earlier studies on spontaneous mutant mice and animals with "hypogranular" cerebella indicate that regression of surplus CFs requires normal generation of granule cells and their axons, parallel fibers (PFs), and normal formation of PF-PC synapses. Our understanding of how PF-PC synapse formation affects development of CF-PC synapse has been greatly advanced by analyses of mutant mice deficient in glutamate receptor delta2 subunit (GluRdelta2), an orphan receptor expressed selectively in PCs. Deletion of GluRdelta2 results in impairment of PF-PC synapse formation, which leads to defects in development of CF-PC synapses. In this article, we review how impaired PF-PC synapse formation affects wiring of CFs to PCs based mostly on our data on GluRdelta2 knockout mice. We propose a new scheme that CF-PC synapses are shaped by the three consecutive events, namely functional differentiation of multiple CFs into one strong and a few weak inputs from P3 to P7, "early phase" of CF synapse elimination from P7 to around P11, and "late phase" of CF synapse elimination from around P12. Normal PF-PC synapse formation is required for the "late phase" of CF synapse elimination.

Spontaneous hyperactivity in mutant mice lacking the NMDA receptor GluRepsilon1 subunit is aggravated during exposure to 0.1 MAC sevoflurane and is preserved after emergence from sevoflurane anaesthesia.

BACKGROUND AND OBJECTIVE: Patients who awake from sevoflurane anaesthesia with symptoms of agitation may have some underlying functional substrate that is sensitive to the low concentrations of anaesthetic encountered during emergence. One candidate for such a substrate could be neurocircuitry implied in the pathophysiology of both agitation and movement disorders with hyperactivity. We postulated that hyperactive animals would show a further increase in activity in the presence of low concentrations of volatile anaesthetics, such as sevoflurane. METHODS: To confirm our hypothesis, we examined the effects of two subanaesthetic concentrations of sevoflurane, isoflurane and halothane (0.1 and 0.2 MAC (minimum alveolar concentration)) on spontaneous activity in N-methyl-d-aspartate receptor GluRepsilon1 subunit knockout mice exhibiting locomotor hyperactivity in a novel environment and compared these results with those for wild-type controls. We also compared the effects of anaesthetic concentrations of sevoflurane (1.2 MAC) on mice activity during postanaesthesia recovery. RESULTS: Out of the three anaesthetics used, only sevoflurane administered at 0.1 MAC caused a significantly different response between the two experimental groups. Exposure to this subanaesthetic concentration of sevoflurane reduced the activity of wild-type mice, whereas mutant animals showed a further increase in hyperactivity. The effects of 1.2 MAC sevoflurane anaesthesia on mice activity during postanaesthesia recovery also differed significantly between the two genotypes. Exposure to anaesthetic concentrations of sevoflurane had a sedative effect on wild-type mice, whereas mutant mice preserved their high levels of activity upon emergence from the anaesthesia. CONCLUSIONS: The presence of an inherent anomaly in mutant mice that becomes more manifest during exposure to 0.1 MAC sevoflurane and is still present after the emergence from sevoflurane anaesthesia suggests the presence of and necessitates a search for some putative substrate that may, by analogy, underlie emergence agitation in the clinical setting.

Anti-aquaporin 4 antibody in selected Japanese multiple sclerosis patients with long spinal cord lesions.

Multiple sclerosis (MS) in Asian populations is often characterized by the selective involvement of the optic nerve (ON) and spinal cord (SP) (OSMS) in contrast to classic MS (CMS), where frequent lesions are observed in the cerebrum, cerebellum or brainstem. In Western countries, inflammatory demyelinating disease preferentially involving the ON and SP is called neuromyelitis optica (NMO). Recently, Lennon et al. discovered that NMO-IgG, shown to bind to aquaporin 4 (AQP4), could be a specific marker of NMO and also of Japanese OSMS whose clinical features were identical to NMO having long spinal cord lesions extending over three vertebral segments (LCL). To examine this antibody in larger populations of Japanese OSMS patients in order to know its epidemiological and clinical spectra, we established an immunohistochemical detection system for the anti-AQP4 antibody (AQP4-Ab) using the AQP4-transfected human embryonic kidney cell line (HEK-293) and confirmed AQP4-Ab positivity together with the immunohistochemical staining pattern of NMO-IgG in approximately 60% of Japanese OSMS patients with LCL. Patients with OSMS without LCL and those with CMS were negative for this antibody. Our results accorded with those of Lennon et al. suggest that Japanese OSMS with LCL may have an underlying pathogenesis in common with NMO.

Roles of glutamate receptor delta 2 subunit (GluRdelta 2) and metabotropic glutamate receptor subtype 1 (mGluR1) in climbing fiber synapse elimination during postnatal cerebellar development.

Climbing fiber (CF) synapse formation onto cerebellar Purkinje cells (PCs) is critically dependent on the synaptogenesis from parallel fibers (PFs), the other input to PCs. Previous studies revealed that deletion of the glutamate receptor delta2 subunit (GluRdelta2) gene results in persistent multiple CF innervation of PCs with impaired PF synaptogenesis, whereas mutation of the metabotropic glutamate receptor subtype 1 (mGluR1) gene causes multiple CF innervation with normal PF synaptogenesis. We demonstrate that atypical CF-mediated EPSCs (CF-EPSCs) with slow rise times and small amplitudes coexisted with typical CF-EPSCs with fast rise times and large amplitudes in PCs from GluRdelta2 mutant cerebellar slices. CF-EPSCs in mGluR1 mutant and wild-type PCs had fast rise times. Atypical slow CF responses of GluRdelta2 mutant PCs were associated with voltage-dependent Ca(2+) signals that were confined to PC distal dendrites. In the wild-type and mGluR1 mutant PCs, CF-induced Ca(2+) signals involved both proximal and distal dendrites. Morphologically, CFs of GluRdelta2 mutant mice extended to the superficial regions of the molecular layer, whereas those of wild-type and mGluR1 mutant mice did not innervate the superficial one-fifth of the molecular layer. It is therefore likely that surplus CFs of GluRdelta2 mutant mice form ectopic synapses onto distal dendrites, whereas those of wild-type and mGluR1 mutant mice innervate proximal dendrites. These findings suggest that GluRdelta2 is required for consolidating PF synapses and restricting CF synapses to the proximal dendrites, whereas the mGluR1-signaling pathway does not affect PF synaptogenesis but is involved in eliminating surplus CF synapses at the proximal dendrites.

The Lurcher mutation reveals Ca(2+) permeability and PKC modification of the GluRdelta channels.

The physiological function of the GluRdelta subfamily which is one of the glutamate receptor (GluR) channel subunits has not yet been clarified, because no GluR channel activity has been detected in heterologous expression systems. The Lurcher mutation, a point mutation of the GluRdelta2 subunit, converts it into a constitutively active and cation-permeating channel. We introduced this mutation into GluRdelta1 and GluRdelta2, AMPA-selective, and NMDA-selective GluR channel subunits, and characterized their channel properties. It was shown that the Lurcher mutation alters the gating properties of AMPA- and NMDA-selective GluR channels, but not their cation permeabilities nor metabolic modulations. These findings support the idea that the Lurcher mutant homomeric GluRdelta1 channels are permeable to Ca(2+) as do the mutant GluRdelta2 channels, reflecting their original channel properties. We also found that cation permeability of the mutant GluRdelta1 channels was decreased by TPA, a protein kinase C activator. It indicates the possibility that phosphorylation by PKC activation may inhibit channel with wild-type GluRdelta1 subunit.

Roles of the glutamate receptor epsilon2 and delta2 subunits in the potentiation and prepulse inhibition of the acoustic startle reflex.

We examined the regulation of the acoustic startle response in mutant mice of the N-methyl-D-aspartate (NMDA)- and delta-subtypes of the glutamate receptor (GluR) channel, which play important roles in neural plasticity in the forebrain and the cerebellum, respectively. Heterozygous mutant mice with reduced GluRepsilon2 subunits of the NMDA receptor showed strongly enhanced startle responses to acoustic stimuli. On the other hand, heterozygous and homozygous mutation of the other NMDA receptor GluRepsilon subunits exerted no, or only small effects on acoustic startle responses. The threshold of the auditory brainstem response of the GluRepsilon2-mutant mice was comparable to that of the wild-type littermates. The primary circuit of the acoustic startle response is a relatively simple oligosynaptic pathway located in the lower brainstem, whilst the expression of GluRepsilon2 is restricted to the forebrain. We thus suggest that the NMDA receptor GluRepsilon2 subunit plays a role in the regulation of the startle reflex. Ablation of the cerebellar Purkinje cell-specific delta2 subunit of the GluR channel exerted little effect on the acoustic startle response but resulted in the enhancement of prepulse inhibition of the reflex. Because inhibition of the acoustic startle response by a weak prepulse is a measure of sensorimotor gating, the process by which an organism filters sensory information, these observations indicate the involvement of the cerebellum in the modulation of sensorimotor gating.

NMDA receptor subunits GluRepsilon1, GluRepsilon3 and GluRzeta1 are enriched at the mossy fibre-granule cell synapse in the adult mouse cerebellum.

Cerebellar N-methyl-D-aspartate (NMDA) receptors are concentrated in the granular layer and are involved in motor coordination and the induction of long-term potentiation at mossy fibre-granule cell synapses. In the present study, we used immunohistochemistry to examine the distribution of NMDA receptor subunits in the adult mouse cerebellum. We found that appropriate pepsin pretreatment of sections greatly enhanced the sensitivity and specificity of immunohistochemical detection. As a result, intense immunolabelling for GluRepsilon1 (NR2A), GluRepsilon3 (NR2C), and GluRzeta1 (NR1) all appeared in synaptic glomeruli of the granular layer. Double immunofluorescence showed that these subunits were colocalized in individual synaptic glomeruli. Within the glomerulus, NMDA receptor subunits were located between centrally-located huge mossy fibre terminals and peripherally-located tiny Golgi axon terminals. By immunoelectron microscopy, all three subunits were detected at the postsynaptic junction in granule cell dendrites, forming synapses with mossy fibre terminals. Consistent with the known functional localization, GluRepsilon1, GluRepsilon3, and GluRzeta1 are, thus, anatomically concentrated at the mossy fibre-granule cell synapse. By contrast, immunohistochemical signals were very low in Purkinje cell somata and dendrites in the molecular layer. The lack of GluRzeta1 immunolabelling in Purkinje cells was unexpected because the cells express GluRzeta1 mRNA at high levels and high levels of GluRzeta1 protein in the molecular layer were revealed by immunoblot. As Purkinje cells are exceptionally lacking GluRepsilon expression, the discrepant result may provide in vivo evidence suggesting the importance of accompanying GluRepsilon subunits in synaptic localization of GluRzeta1.

Differential palmitoylation of two mouse glutamate receptor interacting protein 1 forms with different N-terminal sequences.

Glutamate receptor interacting protein (GRIP) is a member of the PDZ domain-containing protein family that is localized in the postsynaptic density area. This protein has been reported to interact specifically with the C-termini of AMPA-selective glutamate receptor channel subunits, GluRalpha2 and GluRalpha3 through its PDZ domains. To clarify the physiological functions of GRIP, we cloned mouse GRIP1, and found that there are three sites for alternative splicing and two putative translational start codons by characterizing GRIP1 cDNA clones and reverse transcription-polymerase chain reaction products. Metabolic labeling of COS-7 cells expressing two N-terminal GRIP1 proteins demonstrated that these proteins differed in their pattern of palmitoylation. These findings suggested that the molecular diversity of GRIP1 underlies the localization and functional heterogeneity of this protein.

Synchronized disappearance of serum HCV-RNA, anti-U1 RNP, anti-La/SS-B, and anti-Scl-70 in a patient with chronic hepatitis.

The authors report a rare case of chronic hepatitis in whom normalization of serum aminotransferases was associated with disappearance of serum hepatitic C virus (HCV)-ribonucleic acid (RNA), anti-U1 RNP, anti-La/SS-B, and anti-Scl-70 antibodies without treatment of interferon or corticosteroids. A 27-year-old Japanese woman was diagnosed with chronic hepatitis C, with positive anti-nuclear antibody, anti-U1 RNP, anti-La/SS-B, and anti-Scl-70 antibodies. Histopathologic examination of a liver biopsy specimen showed a periportal interface hepatitis with a predominantly lymphoplasmacytic necroinflammatory infiltrate and lobular hepatitis. After two-year treatment with ursodeoxycholic acid (UDCA), serum aminotransferases normalized and serum HCV-RNA, anti-U1 RNP, anti-La/SS-B, and anti-Scl-70 antibodies disappeared. It was unclear whether disappearance of HCV-RNA was spontaneous, due to some immunomodulating effects of UDCA, or other unknown mechanism, but host immune response may be associated with HCV elimination.

Characterization of the glutamatergic system for induction and maintenance of allodynia.

Glutamate is the main excitatory neurotransmitter in the central nervous system and has been shown to be involved in spinal nociceptive processing. We previously demonstrated that intrathecal (i.t.) administration of prostaglandin (PG) E(2) and PGF(2 alpha) induced touch-evoked pain (allodynia) through the glutamatergic system by different mechanisms. In the present study, we characterized glutamate receptor subtypes and glutamate transporters involved in induction and maintenance of PGE(2)- and PGF(2 alpha)-evoked allodynia. In addition to PGE(2) and PGF(2 alpha), N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), but not kainate, induced allodynia. PGE(2)- and NMDA-induced allodynia were observed in NMDA receptor epsilon 4 (NR2D) subunit knockout (GluR epsilon 4(-/-)) mice, but not in epsilon 1 (NR2A) subunit knockout (GluR epsilon 1(-/-)) mice. Conversely, PGF(2 alpha)- and AMPA-induced allodynia were observed in GluR epsilon 1(-/-) mice, but not in GluR epsilon 4(-/-) mice. The induction of allodynia by PGE(2) and NMDA was abolished by the NMDA receptor epsilon 2 (NR2B) antagonist CP-101,606 and neonatal capsaicin treatment. PGF(2 alpha)- and AMPA-induced allodynia were not affected by CP-101,606 and by neonatal capsaicin treatment. On the other hand, the glutamate transporter blocker DL-threo-beta-benzyloxyaspartate (DL-TBOA) blocked all the allodynia induced by PGE(2), PGF(2 alpha), NMDA, and AMPA. These results demonstrate that there are two pathways for induction of allodynia mediated by the glutamatergic system and suggest that the glutamate transporter is essential for the induction and maintenance of allodynia.

Purkinje cell-specific and inducible gene recombination system generated from C57BL/6 mouse ES cells.

Spatiotemporally restricted gene targeting is needed for analyzing the functions of various molecules in a variety of biological phenomena. We have generated an inducible cerebellar Purkinje cell-specific gene targeting system. This was achieved by establishing a mutant mouse line (D2CPR) from a C57BL/6 mouse ES cell line, which expressed a fusion protein consisting of the Cre recombinase and the progesterone receptor (CrePR). The Purkinje cell-specific expression of CrePR was attained by inserting CrePR into the glutamate receptor delta2 subunit (GluRdelta2) gene, which was expressed specifically in the Purkinje cells. Using the transgenic mice carrying the Cre-mediated reporter gene, we showed that the antiprogesterone RU486 could induce recombinase activity of the CrePR protein specifically in the mature cerebellar Purkinje cells of the D2CPR line. Thus this mutant line will be a useful tool for studying the molecular function of mature Purkinje cells by manipulating gene expression in a temporally restricted manner.

Changes in titers of antimitochondrial and antinuclear antibodies during the course of primary biliary cirrhosis.

A case of primary biliary cirrhosis (PBC) in whom a complete biochemical (serum bilirubin, transaminases and alkaline phosphatase) remission was noted after combination treatment with ursodeoxycholic acid (UDCA) and corticosteroid is reported. The antimitochondrial antibody (AMA) detected by indirect immunofluorescence was initially positive, and the antinuclear antibody (ANA) was negative, but these two antibodies subsequently fluctuated independently (AMA-positive/ANA-negative, AMA-negative/ANA-negative, AMA-negative/ANA-positive, AMA-positive/ANA-positive, and again AMA-negative/ANA-positive) in spite of a lack of histopathological improvement in the liver after treatment. The clinical presentation in our case suggests that in some cases the diagnosis of PBC or so-called autoimmune cholangitis (AIC) might depend on the 'phase' of the same disease. Our results also suggest that detailed immunoreactive profiles against 2-oxo-acid dehydrogenase complex (2-OADC) enzymes by using immunoblotting, together with a serial histological examination, should provide more precise information for a diagnosis of PBC.

Clinical features and treatment of hepatocellular carcinoma in eight patients older than eighty years of age.

BACKGROUND/AIMS: Most-hepatocellular carcinoma patients are between 40 and 60 years of age, but an increasing number of elderly patients with hepatocellular carcinoma is expected in the future because of the increase in life expectancy seen in many countries. Since elderly patients have a high incidence of comorbid illnesses, it should be useful to examine the clinical features of these patients to select the optimal management strategy for hepatocellular carcinoma. METHODOLOGY: A retrospective review of 111 patients with hepatocellular carcinoma was undertaken to examine the clinical features of 8 patients older than 80 years of age. RESULTS: In the 111 patients with hepatocellular carcinoma, the ratio of males to females was 81:30 and the peak incidence of hepatocellular carcinoma was noted in the seventh and eighth decades in males and females, respectively. Of these, 21 (19%) were type "B" [seropositive for hepatitis B surface antigen (HBsAg) and seronegative for antibody to the hepatitis C virus (anti-HCV)], 69 (62%) were type "C" (seronegative for HBsAg and seropositive for anti-HCV), 3 (3%) were type "B + C" (seropositive for both HBsAg and anti-HCV), and 18 (16%) were type "non-B non-C" (seronegative for both HBsAg and anti-HCV). The peak incidences of type "B" were in the sixth decade, whereas those of type "C" were in the seventh decade in both males and females. Patients with "non-B non-C" were common in their seventies. Of the 111 patients, 6 (5 males and 1 female) were older than 80 years at the time of diagnosis and 2 females became 80 years old during the course of follow-up of hepatocellular carcinoma. All but one of these patients were anti-HCV-positive, stage and clinical stage I or II according to the criteria defined by the Liver Cancer Study Group of Japan, and underwent transcatheter arterial embolization and/or transcatheter arterial infusion chemotherapy. Transcatheter arterial embolization/transcatheter arterial infusion or percutaneous ethanol injection therapy was well tolerated in these patients, and the outcome of these patients was good. However, concomitant underlying diseases other than liver diseases made it impossible or difficult to apply an aggressive management protocol for hepatocellular carcinoma in some patients. CONCLUSIONS: Our results suggest that the overall treatment of hepatocellular carcinoma in the elderly should be similar to that in younger patients, but may be restricted by the concomitant underlying diseases specific to advanced age.

Serial changes in enzyme inhibitory antibody to pyruvate dehydrogenase complex during the course of primary biliary cirrhosis.

To assess the usefulness of enzyme inhibition assay for the diagnosis of primary biliary cirrhosis (PBC), we determined the serial changes in enzymatic inhibitory antibody to pyruvate dehydrogenase complex (PDC) in patients with PBC, and compared the results to those of immunofluorescence and immunoblotting. Forty-nine sera from 19 patients with PBC who were followed-up for at least 16 months were tested for antimitochondrial antibodies (AMA) by indirect immunofluorescence, immunoblotting on bovine heart mitochondria, and enzyme inhibition assay using commercially available TRACE Enzymatic Mitochondrial Antibody (M2) Assay (EMA) kit. Of the 49 sera, 39 (80%), 35 (71%), 38 (78%), 31 (63%), and 36 (73%) were positive for AMA by immunofluorescence, for immunoglobulin G (IgG), IgM, and IgA class antibody against E2 subunit of PDC (PDC-E2) by immunoblotting, and for enzymatic inhibitory antibody to PDC by EMA, respectively. AMA titers determined by immunofluorescence did not change in 9 patients (47%), increased in 4 (21%), decreased in 3 (16%), and fluctuated in 3 (16%) during follow-up. The number of anti-M2 bands by immunoblotting did not change in 9 (47%), increased in 6 (32%), decreased in 2 (11%), and fluctuated in 2 (11%). Units of PDC activity by EMA did not change markedly in 16 (84%), increased in 2 (11%), and fluctuated in 1 (5%). Positive EMA results were common in cases with high levels of serum alkaline phosphatase and IgM, and the units of PDC activity by EMA correlated significantly and inversely with AMA titers by immunofluorescence, and serum reactivity to PDC-E2 by immunoblotting, respectively. There was no correlation between serial changes in biochemical data and units of PDC activity by EMA. In three patients who showed a decrease in AMA titers, AMA titers correlated more with EMA results than immunoblotting. Moreover, in a patient with fluctuating AMA titers, the units of PDC activity by EMA paralleled AMA titers. Our results suggest that EMA is useful for the diagnosis of AMA-positive PBC, and also could be used for monitoring the disease course in PBC.