Axin, a negative regulator of the Wnt signaling pathway, forms a complex with GSK-3beta and beta-catenin and promotes GSK-3beta-dependent phosphorylation of beta-catenin

Glycogen synthase kinase-3 (GSK-3) mediates epidermal growth factor, insulin and Wnt signals to various downstream events such as glycogen metabolism, gene expression, proliferation and differentiation. We have isolated here a GSK-3beta-interacting protein from a rat brain cDNA library using a yeast two-hybrid method. This protein consists of 832 amino acids and possesses Regulators of G protein Signaling (RGS) and dishevelled (Dsh) homologous domains in its N- and C-terminal regions, respectively. The predicted amino acid sequence of this GSK-3beta-interacting protein shows 94% identity with mouse Axin, which recently has been identified as a negative regulator of the Wnt signaling pathway; therefore, we termed this protein rAxin (rat Axin). rAxin interacted directly with, and was phosphorylated by, GSK-3beta. rAxin also interacted directly with the armadillo repeats of beta-catenin. The binding site of rAxin for GSK-3beta was distinct from the beta-catenin-binding site, and these three proteins formed a ternary complex. Furthermore, rAxin promoted GSK-3beta-dependent phosphorylation of beta-catenin. These results suggest that rAxin negatively regulates the Wnt signaling pathway by interacting with GSK-3beta and beta-catenin and mediating the signal from GSK-3beta to beta-catenin.

Metalloproteinase-mediated release of human Fas ligand

Fas ligand (FasL) is a type II integral membrane protein homologous with tumor necrosis factor (TNF). Recent studies indicate that TNF is processed to yield the soluble cytokine by metalloproteinases at the cell surface of activated macrophages and T cells. In the present study, we investigated whether FasL is also released by metalloproteinases. Treatment with hydroxamic acid inhibitors of matrix metalloproteinases specifically led to accumulation of membrane-type FasL (p40) on the surface of human FasL cDNA transfectants and activated human T cells, as estimated by surface immunofluorescence and immunoprecipitation with newly established anti-human FasL monoclonal antibodies. This surface accumulation of mFasL was associated with the decrease of soluble FasL (p27) in the supernatant as estimated by quantitative ELISA and immunoprecipitation with anti-human FasL monoclonal antibodies. These results indicate that human FasL is efficiently released from the cell surface by metalloproteinases like TNF.

A perpendicular-anisotropy CoFeB-MgO magnetic tunnel junction

Magnetic tunnel junctions (MTJs) with ferromagnetic electrodes possessing a perpendicular magnetic easy axis are of great interest as they have a potential for realizing next-generation high-density non-volatile memory and logic chips with high thermal stability and low critical current for current-induced magnetization switching. To attain perpendicular anisotropy, a number of material systems have been explored as electrodes, which include rare-earth/transition-metal alloys, L1(0)-ordered (Co, Fe)-Pt alloys and Co/(Pd, Pt) multilayers. However, none of them so far satisfy high thermal stability at reduced dimension, low-current current-induced magnetization switching and high tunnel magnetoresistance ratio all at the same time. Here, we use interfacial perpendicular anisotropy between the ferromagnetic electrodes and the tunnel barrier of the MTJ by employing the material combination of CoFeB-MgO, a system widely adopted to produce a giant tunnel magnetoresistance ratio in MTJs with in-plane anisotropy. This approach requires no material other than those used in conventional in-plane-anisotropy MTJs. The perpendicular MTJs consisting of Ta/CoFeB/MgO/CoFeB/Ta show a high tunnel magnetoresistance ratio, over 120%, high thermal stability at dimension as low as 40 nm diameter and a low switching current of 49 microA.

SCA17, a novel autosomal dominant cerebellar ataxia caused by an expanded polyglutamine in TATA-binding protein

Genetic etiologies of at least 20% of autosomal dominant cerebellar ataxias (ADCAs) have yet to be clarified. We identified a novel spinocerebellar ataxia (SCA) form in four Japanese pedigrees which is caused by an abnormal CAG expansion in the TATA-binding protein (TBP) gene, a general transcription initiation factor. Consequently, it has been added to the group of polyglutamine diseases. This abnormal expansion of glutamine tracts in TBP bears 47--55 repeats, whereas the normal repeat number ranges from 29 to 42. Immunocytochemical examination of a postmortem brain which carried 48 CAG repeats detected neuronal intranuclear inclusion bodies that stained with anti-ubiquitin antibody, anti-TBP antibody and with the 1C2 antibody that recognizes specifically expanded pathological polyglutamine tracts. We therefore propose that this new disease be called SCA17 (TBP disease).

Axin, a negative regulator of the wnt signaling pathway, directly interacts with adenomatous polyposis coli and regulates the stabilization of beta-catenin

The regulators of G protein signaling (RGS) domain of Axin, a negative regulator of the Wnt signaling pathway, made a complex with full-length adenomatous polyposis coli (APC) in COS, 293, and L cells but not with truncated APC in SW480 or DLD-1 cells. The RGS domain directly interacted with the region containing the 20-amino acid repeats but not with that containing the 15-amino acid repeats of APC, although both regions are known to bind to beta-catenin. In the region containing seven 20-amino acid repeats, the region containing the latter five repeats bound to the RGS domain of Axin. Axin and beta-catenin simultaneously interacted with APC. Furthermore, Axin stimulated the degradation of beta-catenin in COS cells. Taken together with our recent observations that Axin directly interacts with glycogen synthase kinase-3beta (GSK-3beta) and beta-catenin and that it promotes GSK-3beta-dependent phosphorylation of beta-catenin, these results suggest that Axin, APC, GSK-3beta, and beta-catenin make a tetrameric complex, resulting in the regulation of the stabilization of beta-catenin.

Mutations in ATP2C1, encoding a calcium pump, cause Hailey-Hailey disease

Hailey-Hailey disease (HHD, MIM 16960) is inherited in an autosomal dominant manner and characterized by persistent blisters and erosions of the skin. Impaired intercellular adhesion and epidermal blistering also occur in individuals with pemphigus (which is due to autoantibodies directed against desmosomal proteins) and in patients with Darier disease (DD, MIM 124200), which is caused by mutations in a gene encoding a sarco/endoplasmic reticulum (ER)-Golgi calcium pump. We report here the identification of mutations in ATP2C1, encoding the human homologue of an ATP-powered pump that sequesters calcium into the Golgi in yeast, in 21 HHD kindreds. Regulation of cytoplasmic calcium is impaired in cultured keratinocytes from HHD patients, and the normal epidermal calcium gradient is attenuated in vivo in HHD patients. Our findings not only provide an understanding of the molecular basis of HHD, but also underscore the importance of calcium control to the functioning of stratified squamous epithelia.

A mutation in the ceruloplasmin gene is associated with systemic hemosiderosis in humans

We identified a mutation in the ceruloplasmin (Cp) gene in a Japanese family with aceruloplasminemia, some of whose members showed extrapyramidal disorders, cerebellar ataxia, and diabetes mellitus. A post-mortem study of the proband revealed excessive iron deposition mainly in the brain, liver and pancreas. The G to A transition at the splice acceptor site introduces a premature termination codon at the amino acid position 991 by defective splicing, thereby truncating the carboxyl terminus of Cp in affected individuals. We conclude that the mutation in the Cp gene is associated with systemic hemosiderosis in humans.

DIX domains of Dvl and axin are necessary for protein interactions and their ability to regulate beta-catenin stability

The N-terminal region of Dvl-1 (a mammalian Dishevelled homolog) shares 37% identity with the C-terminal region of Axin, and this related region is named the DIX domain. The functions of the DIX domains of Dvl-1 and Axin were investigated. By yeast two-hybrid screening, the DIX domain of Dvl-1 was found to interact with Dvl-3, a second mammalian Dishevelled relative. The DIX domains of Dvl-1 and Dvl-3 directly bound one another. Furthermore, Dvl-1 formed a homo-oligomer. Axin also formed a homo-oligomer, and its DIX domain was necessary. The N-terminal region of Dvl-1, including its DIX domain, bound to Axin directly. Dvl-1 inhibited Axin-promoted glycogen synthase kinase 3beta-dependent phosphorylation of beta-catenin, and the DIX domain of Dvl-1 was required for this inhibitory activity. Expression of Dvl-1 in L cells induced the nuclear accumulation of beta-catenin, and deletion of the DIX domain abolished this activity. Although expression of Axin in SW480 cells caused the degradation of beta-catenin and reduced the cell growth rate, expression of an Axin mutant that lacks the DIX domain did not affect the level of beta-catenin or the growth rate. These results indicate that the DIX domains of Dvl-1 and Axin are important for protein-protein interactions and that they are necessary for the ability of Dvl-1 and Axin to regulate the stability of beta-catenin.

The gene mutated in adult-onset type II citrullinaemia encodes a putative mitochondrial carrier protein

Citrullinaemia (CTLN) is an autosomal recessive disease caused by deficiency of argininosuccinate synthetase (ASS). Adult-onset type II citrullinaemia (CTLN2) is characterized by a liver-specific ASS deficiency with no abnormalities in hepatic ASS mRNA or the gene ASS (refs 1-17). CTLN2 patients (1/100,000 in Japan) suffer from a disturbance of consciousness and coma, and most die with cerebral edema within a few years of onset. CTLN2 differs from classical citrullinaemia (CTLN1, OMIM 215700) in that CTLN1 is neonatal or infantile in onset, with ASS enzyme defects (in all tissues) arising due to mutations in ASS on chromosome 9q34 (refs 18-21). We collected 118 CTLN2 families, and localized the CTLN2 locus to chromosome 7q21.3 by homozygosity mapping analysis of individuals from 18 consanguineous unions. Using positional cloning we identified a novel gene, SLC25A13, and found five different DNA sequence alterations that account for mutations in all consanguineous patients examined. SLC25A13 encodes a 3.4-kb transcript expressed most abundantly in liver. The protein encoded by SLC25A13, named citrin, is bipartite in structure, containing a mitochondrial carrier motif and four EF-hand domains, suggesting it is a calcium-dependent mitochondrial solute transporter with a role in urea cycle function.

Phosphorylation of axin, a Wnt signal negative regulator, by glycogen synthase kinase-3beta regulates its stability

Axin forms a complex with glycogen synthase kinase-3beta (GSK-3beta) and beta-catenin and promotes GSK-3beta-dependent phosphorylation of beta-catenin, thereby stimulating the degradation of beta-catenin. Because GSK-3beta also phosphorylates Axin in the complex, the physiological significance of the phosphorylation of Axin was examined. Treatment of COS cells with LiCl, a GSK-3beta inhibitor, and okadaic acid, a protein phosphatase inhibitor, decreased and increased, respectively, the cellular protein level of Axin. Pulse-chase analyses showed that the phosphorylated form of Axin was more stable than the unphosphorylated form and that an Axin mutant, in which the possible phosphorylation sites for GSK-3beta were mutated, exhibited a shorter half-life than wild type Axin. Dvl-1, which was genetically shown to function upstream of GSK-3beta, inhibited the phosphorylation of Axin by GSK-3beta in vitro. Furthermore, Wnt-3a-containing conditioned medium down-regulated Axin and accumulated beta-catenin in L cells and expression of Dvl-1(DeltaPDZ), in which the PDZ domain was deleted, suppressed this action of Wnt-3a. These results suggest that the phosphorylation of Axin is important for the regulation of its stability and that Wnt down-regulates Axin through Dvl.

Transgenic mice with Alzheimer presenilin 1 mutations show accelerated neurodegeneration without amyloid plaque formation

Familial Alzheimer disease mutations of presenilin 1 (PS-1) enhance the generation of A beta1-42, indicating that PS-1 is involved in amyloidogenesis. However, PS-1 transgenic mice have failed to show amyloid plaques in their brains. Because PS-1 mutations facilitate apoptotic neuronal death in vitro, we did careful quantitative studies in PS-1 transgenic mice and found that neurodegeneration was significantly accelerated in mice older than 13 months (aged mice) with familial Alzheimer disease mutant PS-1, without amyloid plaque formation. However, there were significantly more neurons containing intracellularly deposited A beta42 in aged mutant transgenic mice. Our data indicate that the pathogenic role of the PS-1 mutation is upstream of the amyloid cascade.

A new G-CSF-supported combination chemotherapy, LSG15, for adult T-cell leukaemia-lymphoma: Japan Clinical Oncology Group Study 9303

This phase II trial was performed to evaluate the efficacy of a new granulocyte colony-stimulating factor (G-CSF)-supported multi-agent chemotherapy protocol, LSG15, for aggressive adult T-cell leukaemia-lymphoma (ATL). Ninety-six previously untreated patients with aggressive ATL were enrolled and grouped as: acute type (58), lymphoma type (28) and unfavourable chronic type (10). Therapy consisted of seven cycles of VCAP (vincristine, cyclophosphamide, doxorubicin and prednisone), AMP (doxorubicin, ranimustine and prednisone) and VECP (vindesine, etoposide, carboplatin and prednisone). G-CSF was administered during the intervals between chemotherapy until neutrophil reconstitution was achieved. Eighty-one per cent of the 93 eligible patients responded [95% confidence interval (CI), 71.1-88.1%], with 33 patients obtaining complete response (35.5%) and 42 obtaining partial response (45.2%). The median survival time (MST) after registration was 13 months and the median follow-up duration of the 20 surviving patients was 4.2 years (range 2.8-5.6). Overall survival at 2 years was estimated to be 31.3% (95% CI, 22.0-40.5%). Grade 4 haematological toxicity of neutropenia and thrombocytopenia were observed in 65.3% and 52.6% of the patients respectively, but grade 4 non-haematological toxicity was observed in only one patient. LSG15 is feasible with mild non-haematological toxicity and improved the clinical outcome of ATL patients. MST and overall survival at 2 years were superior to those obtained by our previous trials.

Detection of mRNA for the tax1/rex1 gene of human T-cell leukemia virus type I in fresh peripheral blood mononuclear cells of adult T-cell leukemia patients and viral carriers by using the polymerase chain reaction

Expression of human T-cell leukemia virus type I (HTLV-I) is not detectable by immunofluorescence analysis or RNA blot analysis in most fresh peripheral blood mononuclear cells of patients with adult T-cell leukemia or of asymptomatic HTLV-I carriers. However, in this work, mRNA for the HTLV-I tax1/rex1 genes was detected in fresh peripheral blood mononuclear cells of adult T-cell leukemia patients and asymptomatic HTLV-I carriers by using reverse transcription followed by the polymerase chain reaction. By using fresh peripheral blood mononuclear cells, the expression of tax1/rex1 mRNA was detected in five of the six adult T-cell leukemia patients and four of the eight HTLV-I carriers examined. The amounts of tax1/rex1 mRNA detected corresponded to approximately 10(5) to 10(6) times less than that in the HTLV-I-infected MT-2 cell line. These results indicate that, in some individuals infected with HTLV-I, the provirus in circulating blood cells is transcribed in vivo. Thus the expression of viral antigens in circulating blood cells in vivo is suggested.

"Weak gel"-type rheological properties of aqueous dispersions of nonaggregated kappa-carrageenan helices

The rheological properties of kappa-carrageenan helices dispersed in an aqueous medium, which prevents aggregation of helices, were investigated. A dispersion of 1.5% w/w nonaggregated kappa-carrageenan helices exhibited gel-like dynamic mechanical spectra at 20 degrees C; that is, the storage modulus G' predominated over the loss modulus G' ' in the entire frequency range examined (0.5-100 rad/s). However, the observed slight frequency dependence of the moduli and the relatively large value of tan delta (= G' '/G' > 0.1) were typical of so-called weak gels. The magnitude of G' of the kappa-carrageenan weak gels was less than that of conventional gels formed by 0.15% w/w kappa-carrageenan in an aggregating condition at 20 degrees C. Under large deformation, enough for the conventional gels to rupture, the weak gel systems flowed but never ruptured, suggesting that the weak gel-type rheological properties of the kappa-carrageenan dispersions were due to a sufficiently long relaxation time of topological entanglements among double-helical conformers but not due to the formation of a three-dimensionally percolated permanent network.

Purification and characterization of human NTH1, a homolog of Escherichia coli endonuclease III. Direct identification of Lys-212 as the active nucleophilic residue

The human endonuclease III (hNTH1), a homolog of the Escherichia coli enzyme (Nth), is a DNA glycosylase with abasic (apurinic/apyrimidinic (AP)) lyase activity and specifically cleaves oxidatively damaged pyrimidines in DNA. Its cDNA was cloned, and the full-length enzyme (304 amino acid residues) was expressed as a glutathione S-transferase fusion polypeptide in E. coli. Purified wild-type protein with two additional amino acid residues and a truncated protein with deletion of 22 residues at the NH2 terminus were equally active and had absorbance maxima at 280 and 410 nm, the latter due to the presence of a [4Fe-4S]cluster, as in E. coli Nth. The enzyme cleaved thymine glycol-containing form I plasmid DNA and a dihydrouracil (DHU)-containing oligonucleotide duplex. The protein had a molar extinction coefficient of 5.0 x 10(4) and a pI of 10. With the DHU-containing oligonucleotide duplex as substrate, the Km was 47 nM, and kcat was approximately 0.6/min, independent of whether DHU paired with G or A. The enzyme carries out beta-elimination and forms a Schiff base between the active site residue and the deoxyribose generated after base removal. The prediction of Lys-212 being the active site was confirmed by sequence analysis of the peptide-oligonucleotide adduct. Furthermore, replacing Lys-212 with Gln inactivated the enzyme. However, replacement with Arg-212 yielded an active enzyme with about 85-fold lower catalytic specificity than the wild-type protein. DNase I footprinting with hNTH1 showed protection of 10 nucleotides centered around the base lesion in the damaged strand and a stretch of 15 nucleotides (with the G opposite the lesion at the 5'-boundary) in the complementary strand. Immunological studies showed that HeLa cells contain a single hNTH species of the predicted size, localized in both the nucleus and the cytoplasm.

Nickel-catalyzed intermolecular domino reactions

Nickel-catalyzed multiple-component reactions are a promising new type of domino reaction. For instance, a variety of starting materials such as alkenes, alkynes, and unsaturated carbonyl compounds can be connected with high selectivity under reasonably mild conditions. These reactions provide a new route to synthetically important key compounds including dienes, enynes, enol silyl ethers, and carbocycles. Furthermore, an asymmetric version of the reaction is successful. Thus, intermolecular domino reactions should be important reactions for years to come.

Hereditary ceruloplasmin deficiency with hemosiderosis: a clinicopathological study of a Japanese family

A hereditary ceruloplasmin deficiency associated with severe iron deposition in visceral organ and brain tissues found on histopathological examination at autopsy is discussed. Three siblings of consanguineous Japanese parents were studied. Their clinical symptoms were progressive dementia, extrapyramidal disorders, cerebellar ataxia, and diabetes mellitus, all of which appeared when they were between 30 and 50 years old. All had serum ceruloplasmin deficiencies and increased serum ferritin concentrations. The dentate nucleus, thalamus, putamen, caudate nucleus, and liver of each one showed low signal intensities on T1- and T2-weighted magnetic resonance images. Examination of the central nervous system revealed severe destruction of the basal ganglia and dentate nucleus, with considerable iron deposition in neuronal and glial cells, whereas the cerebral cortex showed mild iron deposition in glial cells without neuronal involvement. An electron microscopic study with energy-dispersive x-ray analysis showed iron depositions in the hepatocytes, of both the neural and glial cells of the brain. We consider this a new disease entity because of the primary ceruloplasmin deficiency.

Pathology of early- vs late-onset TTR Met30 familial amyloid polyneuropathy

BACKGROUND

Late-onset type I familial amyloid polyneuropathy (FAP TTR Met30) cases unrelated to endemic foci in Japan show clinical features setting them apart from early-onset cases in endemic foci.

OBJECTIVE

To compare pathologic features between the early- and late-onset types.

METHODS

Pathologic findings in FAP TTR Met30 with onset before age 50 in relation to endemic foci (11 cases) were compared with those in 11 later-onset cases unrelated to endemic foci.

RESULTS

Sural nerve biopsy specimens showed predominantly small-fiber loss in early-onset cases; variable fiber size distribution, axonal sprouting, and relatively preserved unmyelinated fibers characterized late-onset cases. Autopsy cases representing both groups showed amyloid deposition throughout the length of nerves and in sympathetic and sensory ganglia, but amounts were greater in early-onset cases. Amyloid deposition and neuronal cell loss were greater in sympathetic than dorsal root ganglia in early-onset cases; the opposite was true in late-onset cases. Size assessment of remaining neurons in these ganglia suggested predominant loss of small neurons in early-onset cases but loss of neurons of all sizes in late-onset cases. Transthyretin-positive, Congo red-negative amorphous material was more conspicuous in nerves from late- than early-onset cases. In extraneural sites, amyloid was more conspicuous in thyroid and kidney from early-onset cases and in heart and hypophysis from late-onset cases. In early-onset cases, cardiac amyloid deposition was prominent in the atrium and subendocardium but was conspicuous throughout the myocardium in late-onset cases.

CONCLUSION

The pathology of early- and late-onset FAP TTR Met30 correlated well with differences in clinical findings.

Axil, a member of the Axin family, interacts with both glycogen synthase kinase 3beta and beta-catenin and inhibits axis formation of Xenopus embryos

Using a yeast two-hybrid method, we identified a novel protein which interacts with glycogen synthase kinase 3beta (GSK-3beta). This protein had 44% amino acid identity with Axin, a negative regulator of the Wnt signaling pathway. We designated this protein Axil for Axin like. Like Axin, Axil ventralized Xenopus embryos and inhibited Xwnt8-induced Xenopus axis duplication. Axil was phosphorylated by GSK-3beta. Axil bound not only to GSK-3beta but also to beta-catenin, and the GSK-3beta-binding site of Axil was distinct from the beta-catenin-binding site. Furthermore, Axil enhanced GSK-3beta-dependent phosphorylation of beta-catenin. These results indicate that Axil negatively regulates the Wnt signaling pathway by mediating GSK-3beta-dependent phosphorylation of beta-catenin, thereby inhibiting axis formation.

Requirement for human AP endonuclease 1 for repair of 3'-blocking damage at DNA single-strand breaks induced by reactive oxygen species

The major mammalian apurinic/apyrimidinic (AP) endonuclease (APE1) plays a central role in the DNA base excision repair pathway (BER) in two distinct ways. As an AP endonuclease, it initiates repair of AP sites in DNA produced either spontaneously or after removal of uracil and alkylated bases in DNA by monofunctional DNA glycosylases. Alternatively, by acting as a 3'-phosphoesterase, it initiates repair of DNA strand breaks with 3'-blocking damage, which are produced either directly by reactive oxygen species (ROS) or indirectly through the AP lyase reaction of damage-specific DNA glycosylases. The endonuclease activity of APE1, however, is much more efficient than its DNA 3'-phosphoesterase activity. Using whole extracts from human HeLa and lymphoblastoid TK6 cells, we have investigated whether these two activities differentially affect BER efficiency. The repair of ROS-induced DNA strand breaks was significantly stimulated by supplementing the reaction with purified APE1. This enhancement was linearly dependent on the amount of APE1 added, while addition of other BER enzymes, such as DNA ligase I and FEN1, had no effect. Moreover, depletion of endogenous APE1 from the extract significantly reduced the repair activity, suggesting that APE1 is essential for repairing such DNA damage and is limiting in extracts of human cells. In contrast, when uracil-containing DNA was used as the substrate, the efficiency of repair was not affected by exogenous APE1, presumably because the AP endonuclease activity was not limiting. These results indicate that the cellular level of APE1 may differentially affect repair efficiency for DNA strand breaks but not for uracil and AP sites in DNA.

Implantation of ultraflex nitinol stents in malignant tracheobronchial stenoses

STUDY OBJECTIVE

To assess the uncovered Ultraflex nitinol stent (Boston Scientific; Natick, MA) for its efficacy and safety.

DESIGN, SETTING, AND PATIENTS

Between October 1997 and October 1998, we carried out a prospective multicenter study at six hospitals in Japan. Fifty-four Ultraflex stents were inserted in 34 patients with inoperable malignant airway stenosis using a flexible and/or a rigid bronchoscope under fluoroscopic and endoscopic visualization.

MEASUREMENTS AND RESULTS

Clinical, endoscopic examination, and pulmonary function on days 1, 30, and 60 after stent implantation showed improvement. In 19 patients (56%), stent implantation was performed as an emergency procedure because of life-threatening tracheobronchial obstruction. Immediate relief of dyspnea was achieved in 82% of the patients. The dyspnea index improved significantly after implantation (before vs. days 1, 30, and 60; p<0.001). Significant improvements were observed in obstruction of airway diameter (81+/-15% before vs. 14+/-17% on day 1, 12+/-12% on day 30, and 22+/-28% on day 60; p<0.001). Vital capacity (VC), FEV(1), and peak expiratory flow (PEF) increased significantly after stent implantation: before vs immediately after VC (p<0.01), FEV(1) (p<0.001), and PEF (p<0.05). The main complications were tumor ingrowth (24%) and tumor overgrowth (21%). After coagulation with an Nd-YAG laser or argon plasma coagulation, mechanical coring out using the bevel of a rigid bronchoscope was necessary in patients showing tumor ingrowth or overgrowth. Removal and reposition were possible in case of misplacement. There were no problems with migration and retained secretions. The median survival time of patients was 3 months. The 1-year survival rate was 25.4%.

CONCLUSIONS

In this study of the Ultraflex nitinol stent, we have demonstrated that patients were relieved from dyspnea, which contributed to improved quality of life, with minimal complications. This stent can be used safely, even in the subglottic region. Owing to its excellent flexibility and biocompatibility, the stent is also indicated in certain complicated situations, eg, narrow stenosis, hourglass stenosis, curvilinear stenosis, bilateral mainstem bronchial stenoses, and long stenosis of varying diameters.

Re-examination of ex-boxers' brains using immunohistochemistry with antibodies to amyloid beta-protein and tau protein

A histopathological study was carried out on the brains of eight ex-boxers (ages 56 to 83) using conventional histological staining methods and immunocytochemistry with antibodies to amyloid beta-protein and the PHF-related tau protein. All cases showed a large number of tau-immunoreactive neurofibrillary tangles and also beta-protein immunoreactive senile plaques in the cortex. In the areas with many neurofibrillary tangles, neuropil threads with tau-immunoreactivity were also observed, and some of the senile plaque lesions were surrounded by abnormal neurites with tau-immunoreactivity. Moreover, three cases revealed beta-protein-type cerebrovascular amyloid deposits on both leptomeningeal and cortical blood vessels. The present observations indicate that the cerebral pathology of dementia pugilistica is very similar to that of Alzheimer's disease and suggest that these two disorders share some common etiological and pathogenic mechanisms.