Garlic supplementation increases testicular testosterone and decreases plasma corticosterone in rats fed a high protein diet

The effects of garlic supplementation on protein metabolism were investigated by measuring testis testosterone and plasma corticosterone in rats fed diets with different protein levels. In Experiment 1, rats were fed experimental diets with different protein levels (40, 25 or 10 g/100 g casein) with or without 0.8 g/100 g garlic powder. After 28 d of feeding, testosterone contents in the testis were significantly higher and plasma corticosterone concentrations were significantly lower in rats fed 40 and 25% casein diets with garlic powder than in those fed the same diets without garlic powder. Urinary excretion of 17-ketosteroid (an index of testosterone), nitrogen balance and hepatic arginase activity were significantly higher in rats fed the 40% casein diet with garlic powder than in the 40% casein controls. In Experiment 2, the effect of diallyldisulfide (a major volatile sulfur-containing compound in garlic) on the secretion of luteinizing hormone (LH) from the pituitary gland, which regulates testosterone production in the testis, was investigated in anesthetized rats. Plasma LH concentration increased dose dependently after administration of diallyldisulfide (P < 0.01, r = 0.558). These results suggest that dietary supplementation with 0.8 g/100 g garlic alters hormones associated with protein anabolism by increasing testicular testosterone and decreasing plasma corticosterone in rats fed a high protein diet.

Genetic mapping of the dominant albino locus in rainbow trout (Oncorhynchus mykiss)

Albinism in animals is generally a recessive trait, but in Japan a dominant oculocutaneous albino (OCA) mutant strain has been isolated in rainbow trout (Oncorhyncus mykiss). After confirming that this trait is not due to a tyrosinase gene mutation that causes OCA1 (tyrosinase-negative OCA), we combined the amplified fragment length polymorphism (AFLP) technique with bulked segregant analysis (BSA) to map the gene involved in dominant oculocutaneous albinism. Four AFLP markers tightly linked to the dominant albino locus were identified. One of these markers was codominant and we have it converted into a GGAGT-repeat microsatellite marker, OmyD-AlbnTUF. Using this pentanucleotide-repeat DNA marker, the dominant albino locus has been mapped on linkage group G of a reference linkage map of rainbow trout. The markers identified here will facilitate cloning of the dominant albino gene in rainbow trout and contribute to a better understanding of tyrosinase-negative OCA in animals.

Distribution of glucose-6-phosphate dehydrogenase mutations in Southeast Asia

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a heterogeneous enzyme abnormality with high frequency in tropical areas. We performed population screening and molecular studies of G6PD variants to clarify their distribution and features in Southeast Asia. A total of 4317 participants (2019 males, 2298 females) from 16 ethnic groups in Myanmar, Lao in Laos, and Amboinese in Indonesia were screened with a single-step screening method. The prevalence of G6PD-deficient males ranged from 0% (the Akha) to 10.8% (the Shan). These G6PD-deficient individuals and 12 G6PD-deficient patients who had been diagnosed at hospitals in Indonesia and Malaysia were subjected to molecular analysis by a combination of polymerase-chain-reaction-based single-strand conformation polymorphism analysis and direct sequencing. Ten different missense mutations were identified in 63 G6PD-deficient individuals (50 hemizygotes, 11 heterozygotes, and 2 homozygotes) from 14 ethnic groups. One missense mutation (1291 G-->A) found in an Indonesian Chinese, viz., G6PD Surabaya, was previously unknown. The 487 G-->A (G6PD Mahidol) mutation was widely seen in Myanmar, 383 T-->C (G6PD Vanua Lava) was specifically found among Amboinese, 871 G-->A (G6PD Viangchan) was observed mainly in Lao, and 592 C-->T (G6PD Coimbra) was found in Malaysian aborigines (Orang Asli). The other five mutations, 95 A-->G (G6PD Gaohe), 1003 G-->A (G6PD Chatham), 1360 C-->T (G6PD Union), 1376 G-->T (G6PD Canton), and 1388 G-->A (G6PD Kaiping) were identified mostly in accordance with distributions reported previously.

[Disseminated atypical mycobacteriosis in a patient with chronic myelogenous leukemia]

A 61-year-old woman with a 6-year history of chronic myelogenous leukemia (CML) presented with recurrent fever in July 1996. Bone marrow aspiration, biopsy and chromosome analysis showed that CML was in the chronic phase. Bone marrow biopsy revealed nonspecific inflammatory lesions. Chest X-ray and computed tomography examinations demonstrated interstitial pneumonia. Cultures of gastric juice and bone marrow yielded colonies of Mycobacterium avium complex (MAC), and a diagnosis of disseminated atypical mycobacteriosis was made. Multidrug treatment including rifampicin, ethambutol, clarithromycin and ciprofloxacin was begun. The cultures subsequently became negative and the fever was resolved. However, fever eventually recurred and the patient died of multiple organ failure in October 1997. since disseminated atypical mycobacteriosis complicating hematological disorders worsens the prognosis, its early diagnosis and prompt treatment are important. Although it is often difficult to identify atypical mycobacterium as a causal agent, frequent culturing of atypical mycobacterium from various sources including bone marrow fluid can be helpful for early diagnosis whenever fever of undetermined origin occurs in patients with hematological disorders.

Mechanisms of ubiquitin-mediated, limited processing of the NF-kappaB1 precursor protein p105

In most cases, target proteins of the ubiquitin system are completely degraded. In several exceptions, such as the first step in the activation of the transcriptional regulator NF-kappaB, the substrate, the precursor protein p105, is processed in a limited manner to yield the active subunit p50. p50 is derived from the N-terminal domain of p105, whereas the C-terminal domain is degraded. The mechanisms involved in this unique process have remained elusive. We have shown that a Gly-rich region (GRR) at the C-terminal domain of p50 is one important processing signal and that it interferes with processing of the ubiquitinated precursor by the 26S proteasome. Also, amino acid residues 441-454 are important for processing under non-stimulated conditions. Lys 441 and 442 serve as ubiquitination targets, whereas residues 446-454 may serve as a ligase recognition motif. Following IkappaB kinase (IKK)-mediated phosphorylation, the C-terminal domain of p105, residues 918-934, recruits the SCF(beta-TrCP) ubiquitin ligase, and ubiquitination by this complex leads to accelerated processing. The two sites appear to be recognized under different physiological conditions by two different ligases, targeting two distinct recognition motifs. We have shown that ubiquitin conjugation and processing of a series of precursors of p105 that lack the C-terminal IKK phosphorylation/TrCP binding domain, is progressively inhibited with increasing number of ankyrin repeats. Inhibition is due to docking of active NF-kappaB subunits to the ankyrin repeat domain in the C-terminal half of p105 (IkappaBgamma). Inhibition is alleviated by phosphorylation of the C-terminal domain that leads to ubiquitin-mediated degradation of the ankyrin repeat domain and release of the anchored subunits. We propose a model that may explain the requirement for two sites: a) a basal site that may be involved in co-translational processing prior to the synthesis of the ankyrin repeat domain; and b) a signal-induced site that is involved in processing/degradation of the complete molecule following cell activation, with rapid release of stored, transcriptionally active subunits.

Targeted deletion of the gene encoding iron regulatory protein-2 causes misregulation of iron metabolism and neurodegenerative disease in mice

In mammalian cells, regulation of the expression of proteins involved in iron metabolism is achieved through interactions of iron-sensing proteins known as iron regulatory proteins (IRPs), with transcripts that contain RNA stem-loop structures referred to as iron responsive elements (IREs). Two distinct but highly homologous proteins, IRP1 and IRP2, bind IREs with high affinity when cells are depleted of iron, inhibiting translation of some transcripts, such as ferritin, or turnover of others, such as the transferrin receptor (TFRC). IRPs sense cytosolic iron levels and modify expression of proteins involved in iron uptake, export and sequestration according to the needs of individual cells. Here we generate mice with a targeted disruption of the gene encoding Irp2 (Ireb2). These mutant mice misregulate iron metabolism in the intestinal mucosa and the central nervous system. In adulthood, Ireb2(-/-) mice develop a movement disorder characterized by ataxia, bradykinesia and tremor. Significant accumulations of iron in white matter tracts and nuclei throughout the brain precede the onset of neurodegeneration and movement disorder symptoms by many months. Ferric iron accumulates in the cytosol of neurons and oligodendrocytes in distinctive regions of the brain. Abnormal accumulations of ferritin colocalize with iron accumulations in populations of neurons that degenerate, and iron-laden oligodendrocytes accumulate ubiquitin-positive inclusions. Thus, misregulation of iron metabolism leads to neurodegenerative disease in Ireb2(-/-) mice and may contribute to the pathogenesis of comparable human neurodegenerative diseases.

Critical role of Caenorhabditis elegans homologs of Cds1 (Chk2)-related kinases in meiotic recombination

Although chromosomal segregation at meiosis I is the critical process for genetic reassortment and inheritance, little is known about molecules involved in this process in metazoa. Here we show by utilizing double-stranded RNA (dsRNA)-mediated genetic interference that novel protein kinases (Ce-CDS-1 and Ce-CDS-2) related to Cds1 (Chk2) play an essential role in meiotic recombination in Caenorhabditis elegans. Injection of dsRNA into adult animals resulted in the inhibition of meiotic crossing over and induced the loss of chiasmata at diakinesis in oocytes of F(1) animals. However, electron microscopic analysis revealed that synaptonemal complex formation in pachytene nuclei of the same progeny of injected animals appeared to be normal. Thus, Ce-CDS-1 and Ce-CDS-2 are the first example of Cds1-related kinases that are required for meiotic recombination in multicellular organisms.

Human T-cell leukemia virus type 1 tax protein activates transcription through AP-1 site by inducing DNA binding activity in T cells

Human T-cell leukemia virus type 1 (HTLV-1) Tax protein induces the expression of various family members of the transcription factor AP-1, such as c-Jun, JunD, c-Fos, and Fra-1, at the level of RNA expression in T cells. We examined the activity of Tax in transcription through AP-1-binding sites (AP-1 site) in T cells. Transient transfection studies showed that Tax activated the expression of a luciferase gene regulated by two copies of an AP-1 site in the human Jurkat T-cell line. Tax activates the expression of viral and cellular genes through two different enhancers: a cAMP-responsive (CRE)-like element and a kappaB element. Two Tax mutants differentially activated expression of these two elements. Tax703 preferentially activated the kappaB element but not the CRE-like one, whereas TaxM22 showed the reverse. In addition, Tax703 and Tax, but not TaxM22, converted cell growth of a mouse T-cell line from being interleukin (IL)-2-dependent to being IL-2-independent. Unlike the wild-type Tax, Tax703 and TaxM22 only weakly activated the AP-1 site in the T-cell line. Thus, Tax seems to activate the AP-1 site via mechanisms distinct from those of kappaB or CRE-like elements, and the activation of the AP-1 site is dispensable for IL-2-independent growth of CTLL-2. Electrophoretic mobility shift assays showed that Tax induced strong binding activity to an AP-1 site in CTLL-2, whereas Tax703 did not, indicating that the induction of binding activity to the AP-1 site is essential for the transcriptional activation by Tax. The binding complex induced by Tax in CTLL-2 contained JunD and Fra-2. Other AP-1 proteins were undetectable. Activation of transcription through the AP-1 site in Jurkat cells by JunD and/or Fra-2 was weak. c-Jun, JunB, and c-Fos activation was greater, although the level was still less than that with Tax. Thus, the induction of AP-1 mRNA by Tax may not be sufficient for a complete activation of AP-1 site by Tax. Our results suggest that Tax activates the transcription of cellular genes with AP-1 sites by inducing the DNA-binding activity of AP-1 proteins in T cells, a mechanism distinct from those of CRE-like and kappaB elements.

Diagnostic efficacy of three-dimensional images by helical CT for lesions in the maxillofacial region

The purpose of this study was to evaluate the efficacy of three-dimensional (3-D) images produced with a helical CT for the diagnosis of lesions occurring in the maxillofacial region. Thirty-four patients, who had lesions in the maxillofacial region, were examined by plain radiography (intra and extraoral) and the helical CT. Further, 3-D images were reconstructed from the data provided by the helical CT using the volume rendering method. These images were compared with plain radiographic images and conventional two-dimensional (2-D) CT images in terms of the information they provided for diagnosis. Using the 3-D images for tumors, bone destruction, inner components, extent of the lesion,the relationship between the lesion and surrounding anatomical landmarks, and the roots of the adjacent teeth were observed in overall views. We conclude that 3-D images produced by helical CT may provide useful information for the diagnosis of lesions.

Early oxidative DNA damages and late development of lung cancer in diesel exhaust-exposed rats

To demonstrate DNA damages in the early stage of diesel exhaust exposure, an inhalation study of 1 through 12 months was conducted. The lung burden of diesel soot increased with increase in exposure duration. Histologically, hyperplastic foci of alveolar epithelia were found at 6-month exposure and became prominent at the 12th month, with slight nuclear atypia and positive p53 staining. The level of 8-OH-hydroxyguanosine (8-OH-dG) in the exposed rat lungs showed an increase from 1 month of exposure, followed by a gradual increase, reaching almost a plateau level at the 9th month. An in vitro experiment demonstrated significant 8-OH-dG formation when diesel particles and H(2)O(2) were added to the DNA solution. The level of bulky aromatic DNA adducts peaked at the 1st month of exposure, followed by a decrease. By the end of the observation period of 30 months, lung tumors developed even in the 6-month exposure group, and the earliest lung tumors were found only in rats that survived longer than 18 months. In conclusion, persisting oxidative stress on DNA induced in the early phase of diesel exhaust exposure, together with inflammation, seems to play an important role in carcinogenesis at advance ages after a long latent period.

Activation of oncogenic transcription factor AP-1 in T cells infected with human T cell leukemia virus type 1

Human T cell leukemia virus type 1 (HTLV-1) Tax protein transforms primary human T cells in vitro. We previously showed that Tax induces the expression of various family members of the transcription factor AP-1 such as c-Jun, JunD, c-Fos, and Fra-1 at the mRNA level in T cells. In this study, we have examined the ability of Tax to activate transcription through the AP-1-binding site (AP-1 site). A transient transfection study showed that Tax can activate transcription through the AP-1-binding site in a human T cell line, whereas any combination of AP-1 proteins did so much less than Tax, indicating that the activation of the AP-1 site by Tax may require a mechanism other than the induction of AP-1 mRNA. Fresh peripheral blood leukemia cells of all surveyed ATL patients displayed constitutive AP-1 DNA-binding activity, whereas no normal individuals did. However, the HTLV-1 genes, including tax, are not significantly expressed in fresh leukemia cells from ATL patients. Our present results suggest that activation of AP-1 occurs through Tax-dependent and -independent mechanisms in HTLV-1-infected T cells, which may play some roles in dysregulated phenotypes of HTLV-1-infected cells.

Activation of HIF1alpha ubiquitination by a reconstituted von Hippel-Lindau (VHL) tumor suppressor complex

Mutations in the VHL tumor suppressor gene result in constitutive expression of many hypoxia-inducible genes, at least in part because of increases in the cellular level of hypoxia-inducible transcription factor HIF1alpha, which in normal cells is rapidly ubiquitinated and degraded by the proteasome under normoxic conditions. The recent observation that the VHL protein is a subunit of an Skp1-Cul1/Cdc53-F-box (SCF)-like E3 ubiquitin ligase raised the possibility that VHL may be directly responsible for regulating cellular levels of HIF1alpha by targeting it for ubiquitination and proteolysis. In this report, we test this hypothesis directly. We report development of methods for production of the purified recombinant VHL complex and present direct biochemical evidence that it can function with an E1 ubiquitin-activating enzyme and E2 ubiquitin-conjugating enzyme to activate HIF1alpha ubiquitination in vitro. Our findings provide new insight into the function of the VHL tumor suppressor protein, and they provide a foundation for future investigations of the mechanisms underlying VHL regulation of oxygen-dependent gene expression.

[Three cases of measles-associated interstitial pneumonia]

It has been reported that measles-associated pneumonia is easily complicated with fatal respiratory failure. During the 6 months from January to June 1998, we treated three young patients with measles-associated pneumonia who had previously been healthy. Their chest X-ray and CT examinations revealed mainly interstitial and partially alveolar pneumonia surrounding extensive areas of bronchiolitis. In one patient, respiratory failure was present, and arterial blood gas analysis showed severe hypoxemia. Therefore, this patient was treated with a mechanical ventilator, which dramatically improved the condition. The other two patients received steroid-pulse therapy and improved rapidly. We believed that in measles-associated pneumonia, steroid pulse therapy is to be recommended for the severely ill patient. According to a report by the Japanese Ministry of Health and Welfare, measles-like disease was widespread in Japan in 1991 and occasionally encountered in 1996. But in Yamanashi Prefecture, the disease was prevalent in 1991, 1994 and 1998. The number of patients in our hospital had reflected the prevalence in the prefecture. It is suggested that the measles is a disease of regional prevalence.

[A study of recovery factor about drug addiction recovery center "DARC"]

This study examines the effectiveness of the 'DARC' (Drug Addiction Rehabilitation Center) and its program in treating patients with drug dependence. DARC is the only rehabilitation facility group managed by recovered drug users in Japan. It uses the 'Twelve Step Program' as part of its recovery regime. Through structured questionnaires, the changes of participants' and ex-participants' everyday behavior, their acceptance of spirituality, attitude toward drugs, self-esteem, their coping skills and loneliness were examined. The results revealed: a.. Negative partial correlation between loneliness and everyday behavior. b.. Negative partial correlation between loneliness and positive/effective coping skills. c.. Positive partial correlation between acceptance of 'spirituality' and attitude toward drugs. d.. Positive partial correlation between acceptance of 'spirituality' and positive/effective coping skills. These results suggest that the acceptance of 'spirituality' and decreasing loneliness are important factors in the recovery from drug dependence.

Familial Parkinson disease gene product, parkin, is a ubiquitin-protein ligase

Autosomal recessive juvenile parkinsonism (AR-JP), one of the most common familial forms of Parkinson disease, is characterized by selective dopaminergic neural cell death and the absence of the Lewy body, a cytoplasmic inclusion body consisting of aggregates of abnormally accumulated proteins. We previously cloned PARK2, mutations of which cause AR-JP (ref. 2), but the function of the gene product, parkin, remains unknown. We report here that parkin is involved in protein degradation as a ubiquitin-protein ligase collaborating with the ubiquitin-conjugating enzyme UbcH7, and that mutant parkins from AR-JP patients show loss of the ubiquitin-protein ligase activity. Our findings indicate that accumulation of proteins that have yet to be identified causes a selective neural cell death without formation of Lewy bodies. Our findings should enhance the exploration of the molecular mechanisms of neurodegeneration in Parkinson disease as well as in other neurodegenerative diseases that are characterized by involvement of abnormal protein ubiquitination, including Alzheimer disease, other tauopathies, CAG triplet repeat disorders and amyotrophic lateral sclerosis.

Synthesis and bioactivities of novel piperidylpyrimidine derivatives: inhibitors of tumor necrosis factor-alpha production

New piperidylpyrimidine derivatives, including quinazolines, were prepared, and their abilities to inhibit TNF-alpha production evaluated. Some compounds showed potent inhibitory activity in mouse macrophages stimulated with LPS. The synthesis and structure activity relationships of these compounds are described.

Constitutive activation of transcription factor AP-1 in primary adult T-cell leukemia cells

Human T-cell leukemia virus type-I (HTLV-I) is the etiologic agent of adult T-cell leukemia (ATL). This study examined the status of the oncogenic transcription factor AP-1 in leukemic cells freshly isolated from patients with ATL. Leukemic cells from peripheral blood of all patients with ATL exhibited constitutive AP-1 DNA binding activity, whereas mononuclear cells from normal individuals did not. In agreement with previous studies, HTLV-I transforming protein, Tax, was found to stimulate the DNA binding activity of AP-1 in a T-cell line. However, HTLV-I genes, including Tax, were not significantly expressed in leukemic cells freshly obtained from patients with ATL. Moreover, all T-cell lines derived from leukemic cells of patients with ATL also displayed constitutive AP-1 DNA binding activity, but expressed little Tax protein. Thus, leukemic cells of patients with ATL appear to have Tax-independent mechanisms that induce AP-1 activity, both in vivo and in vitro. In antibody supershift experiments, AP-1 in fresh leukemic cells and ATL-derived cell lines were found to contain JunD. Consistently, all primary ATL cells and ATL-derived cell lines expressed high levels of JunD messenger RNA. Our results suggest that AP-1 is activated in leukemic cells of patients with ATL through a Tax-independent mechanism and this may play a role in the deregulated phenotypes of ATL leukemic cells. (Blood. 2000;95:3915-3921)

Time to recover from atrial hormonal, mechanical, and electrical dysfunction after successful electrical cardioversion of persistent atrial fibrillation

Although transient atrial dysfunction has been reported after electrical cardioversion of atrial fibrillation (AF), the difference in the time to recover from the atrial hormonal, mechanical, and electrical dysfunction has not been described. Thus, we evaluated the time course of recovery from atrial hormonal, mechanical, and electrical dysfunction after cardioversion in patients with nonvalvular AF. We attempted electrical cardioversion in 87 consecutive patients with nonvalvular AF that had persisted for > or =6 months, and in 24 patients (28%) with maintained sinus rhythm for > or =6 months. To evaluate atrial hormonal, mechanical, and electrical dysfunction in these 24 patients, we measured plasma concentration of atrial natriuretic peptide, the atrial peak velocity in transmitral flow, and the ratio of peak systolic-to-diastolic pulmonary venous flow (S/D ratio) using echocardiography, and the duration and the root mean voltage for the terminal 20 ms (LP20) of the filtered P wave using P-wave signal-averaged electrocardiography. Atrial natriuretic peptide rapidly returned to baseline within 1 day after cardioversion, and maintained these levels for 6 months. Atrial peak velocity in transmitral flow and S/D ratio were significantly increased at 2 weeks, and continued to increase until 1 month, and then reached a plateau. The duration and LP20 began to recover only 6 months after cardioversion. One to 3 years after conversion, the duration and LP20 had nearly reached a plateau, but the latter value remained below normal. In patients with nonvalvular AF of prolonged duration, recovery from atrial electrical dysfunction after sinus conversion took much longer than that from either atrial hormonal or mechanical dysfunction.

SCF(beta)(-TrCP) ubiquitin ligase-mediated processing of NF-kappaB p105 requires phosphorylation of its C-terminus by IkappaB kinase

Processing of the p105 precursor to form the active subunit p50 of the NF-kappaB transcription factor is a unique case in which the ubiquitin system is involved in limited processing rather than in complete destruction of the target substrate. A glycine-rich region along with a downstream acidic domain have been demonstrated to be essential for processing. Here we demonstrate that following IkappaB kinase (IkappaK)-mediated phosphorylation, the C-terminal domain of p105 (residues 918-934) serves as a recognition motif for the SCF(beta)(-TrCP) ubiquitin ligase. Expression of IkappaKbeta dramatically increases processing of wild-type p105, but not of p105-Delta918-934. Dominant-negative beta-TrCP inhibits IkappaK-dependent processing. Furthermore, the ligase and wild-type p105 but not p105-Delta918-934 associate physically following phosphorylation. In vitro, SCF(beta)(-TrCP) specifically conjugates and promotes processing of phosphorylated p105. Importantly, the TrCP recognition motif in p105 is different from that described for IkappaBs, beta-catenin and human immunodeficiency virus type 1 Vpu. Since p105-Delta918-934 is also conjugated and processed, it appears that p105 can be recognized under different physiological conditions by two different ligases, targeting two distinct recognition motifs.

Differential interaction of plakoglobin and beta-catenin with the ubiquitin-proteasome system

Beta-catenin and plakoglobin are closely related armadillo family proteins with shared and distinct properties; Both are associated with cadherins in actin-containing adherens junctions. Plakoglobin is also found in desmosomes where it anchors intermediate filaments to the desmosomal plaques. Beta-catenin, on the other hand, is a component of the Wnt signaling pathway, which is involved in embryonic morphogenesis and tumorigenesis. A key step in the regulation of this pathway involves modulation of beta-catenin stability. A multiprotein complex, regulated by Wnt, directs the phosphorylation of beta-catenin and its degradation by the ubiquitin-proteasome system. Plakoglobin can also associate with members of this complex, but inhibition of proteasomal degradation has little effect on its levels while dramatically increasing the levels of beta-catenin. Beta-TrCP, an F-box protein of the SCF E3 ubiquitin ligase complex, was recently shown to play a role in the turnover of beta-catenin. To elucidate the basis for the apparent differences in the turnover of beta-catenin and plakoglobin we compared the handling of these two proteins by the ubiquitin-proteasome system. We show here that a deletion mutant of beta-TrCP, lacking the F-box, can stabilize the endogenous beta-catenin leading to its nuclear translocation and induction of beta-catenin/LEF-1-directed transcription, without affecting the levels of plakoglobin. However, when plakoglobin was overexpressed, it readily associated with beta-TrCP, efficiently competed with beta-catenin for binding to beta-TrCP and became polyubiquitinated. Fractionation studies revealed that about 85% of plakoglobin in 293 cells, is Triton X-100-insoluble compared to 50% of beta-catenin. These results suggest that while both plakoglobin and beta-catenin can comparably interact with beta-TrCP and the ubiquitination system, the sequestration of plakoglobin by the membrane-cytoskeleton system renders it inaccessible to the proteolytic machinery and stabilizes it.

An autopsy case with clinically and molecular genetically diagnosed Huntington's disease with only minimal non-specific neuropathological findings

An autopsy case with clinically and molecular genetically diagnosed Huntington's disease (HD) accompanied with minimal non-specific neuropathological features was reported. When the patient was 45 years old, he had faulty memory, mood swing, personality change and agitation. Neurological and psychiatric examinations revealed choreoathetoid movements in limbs and trunk, generalized hyperreflexia and mental deterioration. However, cerebellar ataxia and muscle rigidity were not disclosed. Neuroimaging study did not show a definite atrophy of heads of caudate nuclei. Neuroacanthocytosis and Wilson's disease were ruled out by the peripheral blood examination and serum Cu and ceruloplasmin examination. At the age of 55 he died of pneumonia. Post-mortem examination revealed minimal non-specific neuropathological features for HD (Vonsattel's grade 0), that is, no visible fibrillary gliosis in the striatum, and few neuronal loss and only proliferation of astrocytes (astrocytosis) in the striatum. Molecular-genetic study the patient's brain tissues and his youngest son's blood was performed. These studies revealed 40 CAG repeats in the patient, 56 CAG repeats in his youngest son. These results suggest they may be HD. Vonsattel et al. [ 1998] insist that grade 0 comprises 1% of all HD brains, and grade 1 comprises 4% of all HD brains. But we could not find any reports in which the clinical and neuropathological features were described in detail on the cases with clinically and molecular genetically diagnosed HD without specific pathological findings. Therefore, we present in detail the clinical and neuropathological features of such case.

Fulminant hepatitis B following bone marrow transplantation in an HBsAg-negative, HBsAb-positive recipient; reactivation of dormant virus during the immunosuppressive period

It is widely accepted that seroconversion of HBsAg to HBsAb indicates clearance of hepatitis B virus. We describe a 50-year-old man with chronic myelocytic leukemia who developed lethal hepatitis B 22 months after allo-BMT. He had been negative for HBsAg and positive for HBsAb before BMT. Hepatitis B virus latently existing in the liver cells before BMT proliferated during the immunosuppressed period causing fatal hepatitis. Recipients with positive HBsAb should be considered to have the potential for active hepatitis B to emerge after BMT. Bone Marrow Transplantation (2000) 25, 105-108.