Estrogen-Independent Ovary Formation in the Medaka Fish, Oryzias latipes

To investigate whether a female sex steroid, estrogen, acts as a natural inducer of female gonadal sex determination (or ovary formation) in the medaka fish, Oryzias latipes, the effects of an aromatase inhibitor and anti-estrogens on sexual differentiation of gonads were examined. We found that both drugs did not show any discernible effects on the genetically determined sex differentiation in both sexes. However, the aromatase inhibitor impaired the paradoxical effects of androgen (a male sex steroid), and the anti-estrogens inhibited the male-to-female sex reversal caused by estrogen. Treatments of the fertilized eggs with androgen disturbed the gonadal sex developments in both sexes, suggesting that sex steroid synthesis is detrimental to the gonadal sex developments in the medaka embryos. These results are consistent with the previous observation that sex steroids are not synthesized before the onset of gonadal sex differentiation, and suggest that ovary formation in the genetic females of the medaka fish is not dependent on estrogen.

Sterically controlled docking of gold nanoparticles on ferritin surface by DNA hybridization

Novel assemblies of DNA-functionalized gold nanoparticles (DNA-GNPs) have received considerable interest due to their fascinating properties which are desired for various detection applications. In this study, we present innovative GNP assemblies which have a cage-shaped protein ferritin in the center, and discrete GNPs sterically surrounding the central ferritin. These assemblies were constructed by hybridizing DNA-GNP to chemically DNA-modified ferritin, which has a hollow cavity or an iron NP core. Subsequent gel electrophoresis purification and transmission electron microscopy observation showed that ferritin/DNA/GNP assemblies were successfully constructed and can be isolated as independent functional units, which can be used to investigate not only the interaction between the GNPs of complicated GNP clusters but also the interaction between the GNPs and the internalized NP.

Construction of a ferritin dimer by breaking its symmetry

Ferritin has a mono-dispersed structure and biomineralization properties that allow it to form various kinds of nanoparticles and play an important role in modern nanotechnology. Independent nanoparticles synthesized in ferritin are valuable, but moreover a pair of nanoparticles can bring new properties different from those of the independent nanoparticles. In this study, by breaking ferritin's symmetry, we successfully produced ferritin dimers which provide real protein frameworks for nanoparticle dimer formation. Identical nickel hydro-oxide nanoparticle dimers were produced by simply biomineralizing ferritin dimers. The method presented here can produce multi-functional ferritin dimers with different kinds of nanoparticles.

Site-directed delivery of ferritin-encapsulated gold nanoparticles

Newly designed porter proteins, which catch gold nanoparticles and deliver the nanoparticles selectively to a silicon dioxide (SiO(2)) surface under the specific conditions were reported. Recombinant apoferritin subunits, each of which has gold-binding peptide and titanium-binding peptide at the C- and N-terminus, respectively, can efficiently encapsulate a gold nanoparticle. The bio-conjugate, a nanogold and surrounding mutant protein subunits, had a property which can deliver itself to the SiO(2) surface through the interaction. In theory, our genetically manipulated apoferritin subunits can encapsulate gold nanoparticles of various sizes, which is a promising property for applications involving surface plasmon resonance.

Integrated fluidic system for bio-molecule separation

An integrated fluidic system has been fabricated, capable of separating a mixture of different bio-molecules into its components. It is composed of a filter and an actuator; the pressure generated by the actuator sustains the flow of the mixture through the filter. The actuator is made by stacking several layers of conductive polymer. Actuator strain in excess of 10% has been obtained, which corresponds to a fluid flow of 3 microL/min in the fabricated system. The filter consists of an ordered array of Si micro-pillars. A mixture composed of DNA fragments of different length (300 and 400 base-pair) has been effectively separated by using the fabricated filter and chromatographic techniques.

Hexagonal close-packed array formed by selective adsorption onto hexagonal patterns

A patterned two-dimensional hexagonally ordered array of ferritin molecules, the outer surfaces of which had been genetically modified by titanium (Ti) specific binding peptides (minT1-LF), was realized in a self-assembling manner on a hexagonal Ti thin film island made on a silicon substrate. The optimum degree of order was realized at the pH with the maximum selectivity of minT1-LF adsorption on the Ti surface with respect to the silicon dioxide (SiO2) surface. Quartz crystal microbalance (QCM) measurement revealed that minT1-LF adsorbed onto the Ti surface strongly and irreversibly, but adsorbed onto the silicon dioxide surface weakly and reversibly. It was suggested that the concentration of minT1-LF on the Ti pattern promotes hexagonal close-packed ordering and axis aligning.

Size-controlled one-pot synthesis of fluorescent cadmium sulfide semiconductor nanoparticles in an apoferritin cavity

A simple size-controlled synthesis of cadmium sulfide (CdS) nanoparticle (NP) cores in the cavity of apoferritin from horse spleen (HsAFr) was performed by a slow chemical reaction synthesis and a two-step synthesis protocol. We found that the CdS NP core synthesis was slow and that premature CdS NP cores were formed in the apoferritin cavity when the concentration of ammonia water was low. It was proven that the control of the ammonia water concentration can govern the CdS NP core synthesis and successfully produce size-controlled CdS NP cores with diameters from 4.7 to 7.1 nm with narrow size dispersion. X-ray powder diffraction (XRD), energy dispersive spectroscopy (EDS) analysis and high-resolution transmission electron microscopy (HR-TEM) observation characterized the CdS NP cores obtained as cubic polycrystalline NPs, which showed photoluminescence with red shifts depending on their diameters. From the research of CdS NP core synthesis in the recombinant apoferritins, the zeta potential of apoferritin is important for the biomineralization of CdS NP cores in the apoferritin cavity. These synthesized CdS NPs with different photoluminescence properties will be applicable in a wide variety of nano-applications.

Semantic structure in schizophrenia as assessed by the category fluency test: effect of verbal intelligence and age of onset

It has been reported that long-term memory function, including the semantic structure of category, is impaired in patients with schizophrenia. The present study was performed to determine: (1) whether the deficit in semantic structure in schizophrenia is independent of cultural backgrounds, and (2) the effect of age of onset and verbal intelligence on the degradation of semantic structure in these patients. Fifty-seven Japanese patients with schizophrenia and 33 normal control subjects entered the study. The semantic structure was derived by Multidimensional Scaling (MDS) analysis based on data from the ANIMAL category fluency test. The semantic structure was compared between: (1) schizophrenic patients as a whole vs. normal control subjects; (2) earlier onset (age of onset <20 years) vs. later-onset groups of patients; and (3) high Vocabulary score (score of the Vocabulary subtest from the WAIS-R>7) vs. low Vocabulary score patient groups. Normal control subjects demonstrated the domestic/size dimension in semantic structure, while no such dimension was obtained in patients with schizophrenia. The subgroup comparisons revealed that the later onset or the high Vocabulary score group maintained a relatively intact semantic structure compared with the earlier onset or the low Vocabulary score group, respectively. These findings suggest that the deficit in semantic structure in patients with schizophrenia is commonly observed irrespective of cultural backgrounds, and that age of onset and the level of verbal intelligence are closely related to severity of degradation of the semantic structure in schizophrenia.

Stability of exploratory eye movements as a marker of schizophrenia--a WHO multi-center study. World Health Organization

The exploratory eye movements of patients with schizophrenia reportedly differ from those of patients without schizophrenia and healthy controls. In an attempt to determine whether exploratory eye movements provide valid markers for schizophrenia, the present collaborative study was conducted in six countries to analyze the stability of and variation in the following parameters of exploratory eye movements: the number of eye fixations (NEFs) and mean eye scanning length (MESL) in a retention task; the cognitive search score (CSS) that indicates how frequently the eye focused on each important area of a figure in order to recognize it in a comparison task; and the responsive search score (RSS), which reflects the frequency of eye fixations on each section of a figure in response to questioning in a comparison task. In addition, we investigated the validity of the currently employed discriminant function to extract a common feature of schizophrenia by applying it to the findings of the present study. The exploratory eye movements of 145 patients with schizophrenia, 116 depressed patients and 124 healthy controls at seven WHO collaborative centers in six countries were measured using eye mark recorders during viewing of stationary S-shaped figures in two sequential tasks. The RSSs of patients with schizophrenia were found to be significantly lower than those of depressed patients or healthy controls irrespective of geographical location, with no significant difference existing between the RSSs for depressed patients and those for healthy controls. By inserting the RSS and NEF data for each subject into the formula used to calculate discriminant function, patients with schizophrenia could be discriminated from depressed patients and healthy controls with a sensitivity of 89.0% and a specificity of 86.7%. The RSS is an exploratory eye movement parameter that detected schizophrenia irrespective of culture, race and various other subject variables. Furthermore, it is indicative of the stable, significant difference that exists between subjects with and without schizophrenia. The results of discriminant analysis confirm the previously reported validity of discriminant function.

Magnetic resonance imaging study of the cavum septi pellucidi in patients with schizophrenia

OBJECTIVE

High-resolution magnetic resonance imaging was used to evaluate the prevalence of the cavum septi pellucidi (CSP) in 79 normal subjects and 86 patients with schizophrenia.

METHOD

The CSP was assessed by counting the number of consecutive coronal 1-mm slices containing the CSP. A CSP equal to or greater than 6 mm in length was defined as large.

RESULTS

The CSP was found in 74.4% of the patients and 74.7% of the normal subjects, a nonsignificant difference. No difference between groups was found in the prevalence of a large CSP.

CONCLUSIONS

The findings support the idea that a small CSP is a normal anatomical variant. More cases of a large CSP are needed to elucidate the implications of this abnormality in schizophrenia.

Enhancement of cognitive performance in schizophrenia by addition of tandospirone to neuroleptic treatment

OBJECTIVE

The goal of this study was to evaluate the effects of the addition of tandospirone, a serotonin-1A (5-HT(1A)) agonist, to ongoing treatment with typical antipsychotic drugs, on two cognitive domains that are relevant to functional outcome in patients with schizophrenia.

METHOD

Twenty-six patients with schizophrenia who were receiving stable doses of typical antipsychotics were randomly assigned to adjunctive treatment with 30 mg/day of tandospirone or placebo for 6 weeks. Executive function and verbal memory as well as psychopathology were assessed at baseline and after 6 weeks.

RESULTS

Both cognitive measures improved significantly in the patients who received tandospirone; subjects who did not receive tandospirone showed no change. There was no significant change in psychopathology ratings in either group.

CONCLUSIONS

The results suggest the usefulness of 5-HT(1A) agonists for enhancing some types of cognitive performance and possibly social and work function in patients with schizophrenia.

Clinical trial of acetazolamide in SCA6, with assessment using the Ataxia Rating Scale and body stabilometry

OBJECTIVE

To investigate the effect of acetazolamide on spinocerebellar ataxia type 6 (SCA6).

METHODS

Acetazolamide (250-500 mg/day) was administered orally for 88 weeks to 6 patients with SCA6, and its effect was quantitatively monitored using the Ataxia Rating Scale (ARS) and body sway analysis by stabilometry.

RESULTS

During administration of acetazolamide, the ARS score and the amplitude of body sway were significantly reduced compared with before administration. However, the response became weaker after 1 year of treatment.

CONCLUSION

Although this was an open trial, the results suggested that acetazolamide can temporarily reduce the severity of symptoms during the progression of SCA6.

The effect of tandospirone, a serotonin(1A) agonist, on memory function in schizophrenia

BACKGROUND

The purpose of this study was to test the hypothesis that the addition of tandospirone, a 5-HT(1A) partial agonist, to ongoing treatment with typical antipsychotic drugs, would improve memory function in patients with schizophrenia.

METHODS

Eleven outpatients (male/female = 7/4) with schizophrenia who had been on stable doses of haloperidol and biperiden were given tandospirone, 30 mg/day, for 4 weeks. The Wechsler Memory Scale-Revised (WMS-R) was administered at baseline and 4 weeks after the addition of tandospirone. The Brief Psychiatric Rating Scale (BPRS; Total, Positive, and Negative subscale scores) and the Simpson-Angus Scale for Extrapyramidal Symptoms (SAS) were also completed on the two occasions. To exclude the possibility of a practice effect on the WMS-R test, 11 age-matched patients with schizophrenia (M/F = 7/4) were tested at baseline and after a 4-week interval.

RESULTS

Repeated measures analysis of variance revealed a significant time by group (patients with or without tandospirone) effect for the Verbal-, but not the Visual Memory composite scores of the WMS-R test; no significant change was observed in patients without tandospirone, whereas improvement in the Verbal Memory score was noted in patients receiving tandospirone. Moreover, there was improvement in the Inclusion score, an index of memory organization as measured by the Logical Memory subtest of WMS-R, only in patients with tandospirone. Scores on the BPRS and SAS were improved during treatment with tandospirone, but the effects did not reach statistical significance.

CONCLUSIONS

The results suggest that adjunctive treatment with 5-HT(1A) agonists may improve some types of memory function in schizophrenia.

Obstructive jaundice facilitates hepatic metastasis of B16F1 mouse melanoma cells: participation of increased VCAM-1 expression in the liver

Obstructive jaundice facilitates experimental liver metastasis in the rat model, but the detailed mechanisms of this facilitation remain unclear. This study aimed to evaluate the contribution of vascular cell adhesive molecules-1 (VCAM-1) to augmented hepatic metastasis in cases of obstructive jaundice. Obstructive jaundice was induced in male C57BL/6 mice by common bile duct obstruction for 5 days using a Surgiclip. For the biliary decompression, obstructive jaundice was induced for 5 days, followed by removal of the Surgiclip. Liver specimens and blood samples were obtained from animals 5 days after biliary obstruction (OJ5) or sham operation and 2, 5, 11, 14 days after biliary decompression. The expression of VCAM-1 mRNA was increased in the livers from the OJ5 group. Western blot analysis demonstrated increased expression of VCAM-1 protein in the livers of the OJ5 group, in contrast with low VCAM-1 expression in the sham group. The expression of VCAM-1 protein was sustained at high levels at 2 days and decreased at 5 days after biliary decompression (BD5). For the induction of experimental hepatic metastasis, male C57BL/6 mice were randomized to three groups (sham, OJ5, BD5) of six animals each. B16F1 melanoma cells were introduced into the animals by an intraportal injection. Metastatic colonies in the livers were investigated 13 days after inoculation. The mean number of metastatic colonies was significantly increased in the OJ5 group (70.5+/-51.2) compared to that of the sham group (7.2+/-7.9) (p<0.05). This augmentation of hepatic metastasis was abrogated in the BD5 group (16.8+/-20.3). In conclusion, our results suggest that augmented hepatic metastasis in cases of obstructive jaundice are partly mediated through VCAM-1/VLA-4 interaction.

Induction of E-selectin after partial hepatectomy promotes metastases to liver in mice

BACKGROUND

The liver is the most frequent site of tumor metastasis. It has been suggested that partial hepatectomy promotes liver metastasis of malignant disease and that expression of E-selectin, a cell adhesion molecule, plays roles in tumor metastasis. However, no reports are available concerning the expression of E-selectin after hepatectomy.

METHODS

In the present study, we used BALB/c mice subjected to 30% partial hepatectomy after injection of 1 x 10(4) colon 26 cells to determine the effects of partial hepatectomy on tumor metastasis to liver. E-Selectin expression within the liver after partial hepatectomy was evaluated using reverse transcription polymerase chain reaction and Western blotting. In addition, we injected polyclonal antibody to E-selectin into mice in which partial hepatectomy had augmented liver metastasis.

RESULTS

Mice subjected to partial hepatectomy had significantly increased numbers of liver metastases (sham operation, 1.5 +/- 2.0, vs partial hepatectomy, 35.5 +/- 19.3; P < 0.001). Expression of E-selectin mRNA within the liver was markedly increased 4 h after partial hepatectomy, but subsequently decreased at 24 h. E-Selectin protein was detected 8 h after hepatectomy, but subsequently decreased at 24 h as measured by Western blotting. Mice subjected to intraperitoneal injection of neutralizing antibody after operation had significantly decreased numbers of liver metastases (phosphate-buffered saline, 20.6 +/- 9.2, P < 0.05, and normal IgG, 18.0 +/- 8.0, P < 0.05, compared with polyclonal antibody to E-selectin, 5.6 +/- 4.8).

CONCLUSION

Induction of E-selectin by partial hepatectomy promotes hematogenous liver metastasis. Our findings can be applied to surgical treatment of liver tumor to reduce the recurrence of liver metastasis after hepatectomy by inhibiting E-selectin-mediated adhesion using reagents to E-selectin.

The role of aldehyde dehydrogenase isozyme variance in alcohol sensitivity, drinking habits formation and the development of alcoholism in Japan, Taiwan and the Philippines

It is known that aldehyde dehydrogenase (ALDH) responsible for metabolism of acetaldehyde deriving from ethanol has two distinct forms of isozymes: ALDH-I (low Km ALDH) and ALDH-II (high Km ALDH), and that many Orientals lack ALDH-I isozyme genetically. In the present study, the role of ALDH isozyme variance in the alcohol sensitivity, drinking habits formation and the development of alcoholism was investigated in Japan, Taiwan and the Phillipines. Isozyme analysis using isoelectric focusing of hair roots specimens from normal volunteers or schizophrenics revealed that about 42% of Japanese, 35% of Taiwanese and 12% of Phillipines were ALDH-I deficient. Questionnaire study of Japanese volunteers indicated that ALDH-I deficient individuals showed flushing, palpitation and other uncomfortable somatic signs, due to reduced metabolism of acetaldehyde, much more frequently than ALDH-I positive ones. Consequently, it occurred that only 19% (8/42) of ALDH-I deficient persons, in contrast to 49% (29/59) of ALDH-I positive ones, were drinking habitually. Patients with alcoholism showed much smaller percentages of ALDH-I deficiency: 4% (5/113) in Japan and 10% (3/29) in Taiwan, than those of control subjects. Summarizing these data, a hypothesis can be presented that genetically derived difference of ALDH activities is one of the determining factors in the sensitivity to alcohol, formation of drinking habits, and finally in the development of alcoholism, at least among Oriental peoples.

Distinct structural changes detected by X-ray fiber diffraction in stabilization of F-actin by lowering pH and increasing ionic strength

Lowering pH or raising salt concentration stabilizes the F-actin structure by increasing the free energy change associated with its polymerization. To understand the F-actin stabilization mechanism, we studied the effect of pH, salt concentration, and cation species on the F-actin structure. X-ray fiber diffraction patterns recorded from highly ordered F-actin sols at high density enabled us to detect minute changes of diffraction intensities and to precisely determine the helical parameters. F-actin in a solution containing 30 mM NaCl at pH 8 was taken as the control. F-actin at pH 8, 30 to 90 mM NaCl or 30 mM KCl showed a helical symmetry of 2.161 subunits per turn of the 1-start helix (12.968 subunits/6 turns). Lowering pH from 8 to 6 or replacing NaCl by LiCl altered the helical symmetry to 2.159 subunits per turn (12.952/6). The diffraction intensity associated with the 27-A meridional layer-line increased as the pH decreased but decreased as the NaCl concentration increased. None of the solvent conditions tested gave rise to significant changes in the pitch of the left-handed 1-start helix (approximately 59.8 A). The present results indicate that the two factors that stabilize F-actin, relatively low pH and high salt concentration, have distinct effects on the F-actin structure. Possible mechanisms will be discussed to understand how F-actin is stabilized under these conditions.

Mikimopine synthase (mis) gene on pRi1724

By determination of the nucleotide sequence adjacent to the right border of T-DNA of the mikimopine-type Ri plasmid (pRi1724) in Agrobacterium rhizogenes, a new open reading frame (ORF) encoding 318 amino acids was found. A transcript of 1.35 kb derived from this ORF was observed in hairy roots of Ajuga reptans by northern blotting analysis. Including its own promoter and terminator, this ORF was isolated from the pRi1724 T-DNA and introduced into tobacco plants by the Agrobacterium-binary vector system. Since mikimopine, an opine and a stereoisomer of cucumopine, was accumulated in all organs of the transgenic tobacco plants, the new ORF was deduced to be the mikimopine synthase gene. For comparison, the nucleotide sequence of cucumopine synthase encoded on pRi2659 was also determined. No homology was found between mikimopine synthase and cucumopine synthase at the nucleotide, but partial homology was found at the amino acid level. Mikimopine synthase and cucumopine synthase produced by a protein expression system using E. coli catalyzed the synthesis of mikimopine and cucumopine from L-histidine and alpha-ketoglutaric acid, requiring NADH as a cofactor. These synthesized opines were identified by paper electrophoresis, TLC and HPLC analyses. The synthesized mikimopine or cucumopine could be degraded by A. rhizogenes strains harboring Ri plasmids encoding the respective catabolic enzyme.

Ventricular enlargement in schizophrenia spectrum patients with prodromal symptoms of obsessive-compulsive disorder

We hypothesized that male patients with schizophrenia spectrum disorders who have prodromal symptoms of obsessive-compulsive disorder (OCD) have ventricular enlargement compared with non-psychotic OCD patients, and that the difference in the ventricular size would offer a clue to the early detection of schizophrenia spectrum disorders. The ventricle-brain ratios (VBRs) in eight male patients with schizophrenia or schizotypal personality disorder (SPD) who had prodromal symptoms of OCD were compared with eight male patients with non-psychotic OCD and 14 normal male comparison subjects using three-dimensional magnetic resonance imaging (MRI). The VBR of the schizophrenia spectrum group was significantly larger than those of the OCD group or comparison subjects. Even the minimum VBR in the schizophrenia spectrum group was larger than the maximum VBR in the OCD group. These results may suggest the usefulness of three-dimensional MRI for early detection of patients with schizophrenia spectrum disorders who manifest OCD symptoms early in the course of the illness.

A novel locus for dominant cerebellar ataxia (SCA14) maps to a 10.2-cM interval flanked by D19S206 and D19S605 on chromosome 19q13.4-qter

Dominantly inherited, late-onset pure cerebellar ataxia is a group of genetically heterogeneous neurodegenerative disorders. Approximately half of these disorders in the Japanese population are caused by moderate expansion of a CAG repeat in the coding region of the CACNA1A gene on chromosome 19p13 (SCA6). However, neither the loci nor the specific mutations for the remaining disorders have been determined. We performed systematic linkage analysis in a three-generation Japanese family with a locus or mutation that differed from those of known spinocerebellar ataxias. The family members with a late onset (> or =39 years old) exhibited pure cerebellar ataxia, whereas those with an early onset (< or =27 years old) first showed intermittent axial myoclonus followed by ataxia. Other neurological signs were sparse, and neuroimaging studies revealed that atrophy was confined to the cerebellum. Multipoint analysis and haplotype reconstruction ultimately traced this novel spinocerebellar ataxia locus (SCA14) to a 10.2-cM interval flanked by D19S206 and D19S605 on chromosome 19q13.4-qter (Zmax = 4.08, corrected for age-dependent penetrance).

Recessively inherited spastic paraplegia associated with ataxia, congenital cataracts, thin corpus callosum and axonal neuropathy

We investigated a consanguineous Japanese family with a complicated form of familial spastic paraplegia (FSP). Three siblings were affected, probably by autosomal recessive inheritance. All showed ataxia, subnormal mentality, congenital cataracts, and slight cerebellar atrophy on CT scans. Spastic paraplegia was predominant in 2 siblings, while ataxia was more marked in the other. Slight but definite atrophy of the corpus callosum and axonal neuropathy were demonstrated in 1 sibling who underwent detailed investigation. Review of similar cases reported in the literature indicates that this recessively inherited disorder probably represents a homogeneous group within the heterogeneous cluster of complicated FSP.

A transcriptional autoregulatory loop for KIN28-CCL1 and SRB10-SRB11, each encoding RNA polymerase II CTD kinase-cyclin pair, stimulates the meiotic development of S. cerevisiae

Alkalization of the medium is associated with and required for the cellular development to meiosis and sporulation in the yeast Saccharomyces cerevisiae. To elucidate the molecular mechanisms for the significance of external alkalization, we isolated mutants defective in division arrest at G1 phase under an alkaline condition. The mutants obtained had recessive alleles of SRB10 encoding the cyclin (SRB11)-dependent protein kinase that phosphorylates the CTD domain of the largest subunit of RNA polymerase II and negatively regulates the transcriptional initiation of certain genes. A delta srb11 deletion mutant showed the same cell cycle defect. When shifted to alkali, wild-type cells decreased transcript levels of G1-cyclin genes (CLN1 to CLN3) and KIN28-CCL1 (encoding another CTD kinase-cyclin pair which, in contrast, stimulates the promoter clearance and transcriptional elongation in most genes), resulting in the accumulation of G1 cells and the hypophosphorylated form of RNA polymerase II and in an increase in cell size. However, under the same conditions, a delta srb10 mutant was defective in these events, except the downregulation of CLN1 and CLN2. The delta srb10 mutation also influenced on the transcript levels of meiosis-inducing genes called IME1 and IME2: the mutation elevated the transcript level of IME1 but reduced that of IME2, resulting in partial defects in premeiotic DNA synthesis and meiosis. Overexpression of KIN28 and CCL1 in wild-type cells impaired the alkali-induced G1 arrest and the rate of meiosis and elevated the transcript levels of SRB11 and IME1. These results indicate that a transcriptional autoregulatory loop for KIN28-CCL1 and SRB10-SRB11 is important for G1 arrest and meiosis. We also found that environmental conditions for meiosis finely regulate the transcript levels of KIN28 and CCL1, such that nitrogen starvation first elevates them but subsequent alkalization of medium decreases them.

Human T-lymphocyte virus type I (HTLV-I)-induced myeloneuropathy in rats: oligodendrocytes undergo apoptosis in the presence of HTLV-I

To investigate the pathogenetic role of human T-lymphocyte virus type I (HTLV-I) in central nervous system disease, a rat model for HTLV-I-associated myelopathy/tropical spastic paraparesis, designated as HAM rat disease, was examined with regard to chronological neuropathology, from early asymptomatic phase to late disease. In the thoracic spinal cord of rats with HTLV-I infection, the first event was the appearance of apoptosis of oligodendrocytes beginning at 7 months after induced infection, thereafter followed by the appearance of white matter degeneration, increase of macrophages/activated microglia and of gemistocytic astrocytes at 12, 15 and 20 months, respectively. In the spinal cord, HTLV-I provirus DNA was evident as early as 4 months after the infection, and HTLV-I pX and the tumor necrosis factor (TNF)-alpha messages began to be expressed at age 7 months, just before or at the same time as the appearance of apoptotic cells. Collective evidence suggests that the apoptotic death of oligodendrocytes, which may be induced either directly by the local expression of HTLV-I or indirectly by TNF-alpha, through the transactive function of p40Tax, is the major cause of chronic progressive myeloneuropathy in Wistar-King-Aptekman-Hokudai rats with HTLV-I infection.

Neural correlates of memory organization deficits in schizophrenia. A single photon emission computed tomography study with 99mTc-ethyl-cysteinate dimer during a verbal learning task

Regional cerebral blood flow (rCBF) during a verbal learning task was measured using 99mTc-ethyl-cysteinate dimer and single photon emission computed tomography in 10 patients with schizophrenia and nine normal controls. Verbal repetition was used as a control task. The schizophrenic patients showed failure to spontaneously utilize implicit category information to learn the word lists. In the normal controls, rCBF in the left inferior frontal and left anterior cingulate regions was significantly increased during the verbal learning task, compared with the verbal repetition task. In contrast, there was no significant frontal lobe activation by the verbal learning in the schizophrenic patients. The patients had lower rCBF during the verbal learning task than the controls in the bilateral inferior frontal, left anterior cingulate, right superior frontal, and bilateral middle frontal regions. Activation in the left inferior frontal region was significantly positively correlated with categorical clustering in the task in the controls, but no such correlation was found in the patients. These results indicate that memory organization deficits in schizophrenia may be related to dysfunction in the prefrontal areas, especially in the left inferior frontal region.

Multiple pathways regulating fission yeast mitosis upon environmental stresses

Environmental signals, such as nutrient availability and physiological stresses, modulate the cell cycle and cell size of the fission yeast Schizosaccharomyces pombe. However, little is known about how these signals are transmitted to the central cell cycle regulator, Cdc2, the cyclin-dependent kinase that induces mitosis. We show here genetic evidence that medium alkalization stimulates mitosis and consequently reduces cell size, either through the Nim1-Wee1 cascade, which regulates the inhibitory phosphorylation of Cdc2 at Tyr(15), or through the Cdc2-activating phosphatase, Cdc25. Alkaline stress stimulates phosphorylation of Nim1, accumulation of Cdc25 and dephosphorylation of Cdc2 at Tyr(15). We also show that osmostress stimulates mitosis through two independent pathways: one stimulates accumulation of Cdc25, and another dephosphorylation of Cdc2 at Tyr(15). However, our analysis demonstrates that these environmental stresses can stimulate mitosis independently of dephosphorylation of Cdc2 at Tyr(15). The S. pombe MAP kinase, Spc1, was required for the steady-state level of Cdc25 in the normal cell cycle and for its accumulation in response to alkaline stress and nutritional starvation.

Prevalence of triplet repeat expansion in ataxia patients from Hokkaido, the northernmost island of Japan

Approximately 44% of cases of spinocerebellar ataxia (SCA) in Hokkaido, the northernmost island of Japan, were estimated to be inherited. To determine the prevalence of triplet repeat expansion in hereditary SCA patients, we genotyped seven genetically defined dominant SCAs in 349 patients, including 266 patients from 77 families, 78 probands from unrelated families with hereditary late-onset SCA, and five patients in whom a family history of SCA was not demonstrated. The frequency of each disorder in a total of 155 unrelated families was 23.9% for Machado-Joseph disease (MJD), 29.0% for SCA6, 9.7% for SCA1, 7.7% for SCA2, and 2.6% for dentatorubral-pallidoluysian atrophy. Abnormal expansion of triplet repeats for SCA7 and SCA8 was not detected. A total of 27.1% of the patients had still unknown SCA mutations. In addition, the GAA repeat in the frataxin gene was not abnormally expanded in 13 early-onset SCA patients with clinical features similar to those of Friedreich ataxia. Comparison of our results with those from other centers handling SCA showed that MJD is prevalent throughout Japan, but the frequencies of other dominant SCAs differ considerably even within Japan.

Cyclic AMP regulates cell size of Schizosaccharomyces pombe through Cdc25 mitotic inducer

Nutritional state modulates the cell size of the fission yeast Schizosaccharomyces pombe, such that cells grown in rich medium are larger in size than those in poor medium. This signal is transduced partly through the cyclic AMP-dependent protein kinase cascade. However, little is known about how cyclic AMP interacts with the central cell cycle machinery, Cdc2, the cyclin-dependent kinase that induces mitosis. We show here that cyclic AMP regulates mitosis and cell size, in part, through regulation of protein stability of the Cdc2-activating phosphatase, Cdc25. However, our analysis demonstrates that cyclic AMP can negatively regulate mitosis independently of dephosphorylation of Cdc2 at Tyr(15).

[A clinical trial of acetazolamide for SCA6]

Spinocerebellar ataxia type 6 (SCA 6) is an allelic disorder of episodic ataxia type 2 (EA 2) and is caused by a small CAG repeat expansion in the gene encoding the alpha 1A-voltage-dependent-Ca channel subunit (CACNA 1 A) on chromosome 19p13.1. The disorder starts at adulthood with progressive cerebellar ataxia, and the symptoms often fluctuate at early stage. These clinical features overlap with those of EA 2, which has been known as acetazolamide-responsive ataxia. On this background, we studied the clinical effectiveness of acetazolamide for SCA 6 in 9 consecutive patients. Their clinical severity was serially evaluated by ARS (ataxia rating scale) and gravimetric test, over 32 weeks of oral administration of acetazolamide (250-500 mg/day). Consequently, a significant improvement was observed in ARS and postural sway. Our results indicate that acetazolamide is temporally effective for ameliorating the symptoms of SCA 6. However, its effects for the disease progression need to be examined in more large scales in number and duration.

Treatment of obstructive sleep apnea syndrome with a Kampo-formula, San'o-shashin-to: a case report

The following describes a 76-year-old male with obstructive sleep apnea syndrome successfully treated with a Kampo-formula, San'o-shashin-to (Formula medicamentorum tres ad dispellendi cordis). Polysomnography, performed before and after administration of San'o-shashin-to, revealed that the apnea index decreased from 11.1 events/hour to 4.1 events/hour, and that the apnea plus hypopnea index decreased from 18.4 events/hour to 10.7 events/hour. The patient was normo-weight (body mass index: 20.4 kg/m2), and events of sleep apnea and hypopnea were mostly noted during a non-rapid eye movement sleep. It is possible that San'o-shashin-to has some alleviating effects on the upper airway resistance during sleep.

A rat model of human T lymphocyte virus type I (HTLV-I) infection: in situ detection of HTLV-I provirus DNA in microglia/macrophages in affected spinal cords of rats with HTLV-I-induced chronic progressive myeloneuropathy

To investigate the pathogenetic role of human T lymphocyte virus type I (HTLV-I) in central nervous system disease, a rat model for HTLV-I-associated myelopathy/tropical spastic paraparesis, designated as HAM rat disease, has been established. Wistar-King-Aptekman-Hokudai strain rats with induced HTLV-I infection develop a chronic progressive myeloneuropathy with paraparesis of hind limbs after an incubation period of 15 months. In the affected spinal cord in these rats, white matter degeneration, demyelination and vacuolar change with microglia/macrophage infiltration are present as are the provirus DNA and the virus mRNA. To identify infected cells in the affected lesions, we carried out in situ hybridization of amplified fragments of the provirus DNA by polymerase chain reaction on thin sections, plus immunohistochemistry on the same sections. The provirus DNA was localized in some microglia/macrophages in the spinal cord lesion. In addition, the HTLV-I provirus was clearly evident not only in ED-1-negative lymphoid cells but also in ED-1-positive macrophages from lymph nodes. These observations suggest that cells of microglia/macrophage lineage may be one of dominant viral reservoirs in the spinal cords and lymph nodes in HAM rat disease. These infected microglia/macrophages may relate to cause the myeloneuropathy through neurotoxic cytokine synthesis.

Effect of the length and effective diameter of F-actin on the filament orientation in liquid crystalline sols measured by x-ray fiber diffraction

We examined factors that affect the filament orientation in F-actin sols to prepare highly well-oriented liquid crystalline sols suitable for x-ray fiber diffraction structure analysis. Filamentous particles such as F-actin spontaneously align with one another when concentrated above a certain threshold concentration. This alignment is attributed to the excluded volume effect of the particles. In trying to improve the orientation of F-actin sols, we focused on the excluded volume to see how it affects the alignment. The achievable orientation was sensitive to the ionic strength of the solvent; the filaments were better oriented at lower ionic strengths, where the effective diameter of the filament is relatively large. Sols of longer filaments were better oriented than those of shorter filaments at the same concentration, but the best achievable orientation was limited, probably because of the filament flexibility. The best strategy for making well-oriented F-actin sols is therefore to concentrate F-actin filaments of relatively short length (<1 micrometer) by slow centrifugation in a low-ionic-strength solvent (<30 mM).

Role of the outermost subdomain of Salmonella flagellin in the filament structure revealed by electron cryomicroscopy

A mutant strain of Salmonella typhimurium, SJW46, has flagellar filaments supercoiled in the same form as the wild-type strain, SJW1103, and swims normally. However, its flagellar filaments are mechanically unstable and show anomalous behaviors of polymorphism. Flagellin from SJW46 has a large central deletion from Ala204 to Lys292 of SJW1103 flagellin, which has been thought to be located in the outer surface of the filament. Since the filament structure is determined by intersubunit interactions of the terminal regions in the densely packed core of the filament, no serious involvement of the deleted portion was expected in the filament stability and polymorphism. In order to locate the deleted portion and to understand the underlying mechanism of these anomalous characteristics, we carried out structure analysis of the L-type straight filament reconstituted from a mutant flagellin of SJW46 (SJW46S) and compared the structure with that of the SJW1660 filament, which is also the L-type but composed of flagellin with no deletion. The deleted portion was identified as the outermost subdomain, and the structure in the core region showed no appreciable differences. The structure revealed the previously identified folding of flagellin in further detail, and the significance of intersubunit interactions between outer domains, which are present in the SJW1660 filament but absent in the SJW46 filament. This suggests that these contacts have a significant contribution to the filament stability and polymorphic behavior, despite the fact that the contacting surface area occupies only a minor portion of the whole intersubunit interactions.

Characterization of transcription of genes involved in hairy root induction on pRi1724 core-T-DNA in two Ajuga reptans hairy root lines

The detailed status of the transcription of genes on pRil724 T-DNA in two independent hairy root lines of the plant Ajuga reptans, Ar-4 and Ar-24, which have several different characteristics, was obtained by Northern blotting and a reverse transcription-polymerase chain reaction (RT-PCR) analysis. In the Northern blotting analysis DNA fragments corresponding to the putative open reading frames (ORFs) as probes, transcripts from putative ORFs 10 (1724rolA), 11 (1724rolB), 12 (1724rolC), 13a and 14, which are homologs to each ORF on pRiA4, were detected in both hairy root lines, whereas no transcripts derived from ORF 13 were detected. The transcription of ORF 13 was, however, detected in the RT-PCR analysis, suggesting a minor expression of ORF 13. All of the putative ORFs were transcribed with their expected directions, since DNA fragments were amplified when the antisense primers were employed in the reverse transcription. We also found that different transcripts with a reverse direction were present at the locations of 1724rolA, 1724rolC and ORF 13a, because the DNA fragments were amplified from the templates when their sense primers were used in the reverse transcription.

Identification of a novel casein kinase-1 homolog in fission yeast Schizosaccharomyces pombe

Fission yeast cells lacking either the ste9+- or rum1+ function cannot enter the cell differentiation pathway upon nutritional starvation. Sterility in both mutants is suppressed by the srs1-S41 mutation. A gene encoding a novel casein kinase-1 (CK1) isoform, cki3+, was isolated as a high-copy-number suppressor gene of the srs1 mutation. Cki3 protein is structurally more related to the Cki/Yck subfamily proteins than those of the Hhp/Hrr25 subfamily. A mutant cki3 gene in which a highly conserved lysine residue in the kinase subdomain II was substituted to arginine lost the ability to recover the growth defect in the srs1 mutant, indicating that catalytic activity was necessary for suppression. Gene disruption revealed that cki3+ was dispensable for cell viability, and cells lacking functional cki3+ exhibited no characteristic phenotype. Thus, S. pombe has three highly related CK1 isoforms (Cki1, Cki2 and Cki3), but none of them has an essential function.

Control of division arrest and entry into meiosis by extracellular alkalisation in Saccharomyces cerevisiae

Limitation of nutrients allows yeast cells to arrest proliferation at G1 phase of the cell cycle and to enter the so-called stationary phase. We show here another pathway for cytostasis, which is associated with extracellular accumulation of bicarbonate and the resulting alkalisation of medium during the proliferation of cells respiring acetate. Alkalisation of medium by addition of bicarbonate or alkaline buffers ceased proliferation at G1 phase of logarithmically growing cells and caused a severe drop in G1-cyclin (CLN1 and CLN2) mRNAs. The arrested cells were heat-shock resistant, suggesting that the cells entered the stationary phase. Cells confluently grown on acetate re-entered into the cell cycle after acidification of the culture medium. These results indicate that external alkalisation is a primary cause of the cytostasis. The alkali-induced G1 arrest was shown to be cyclic AMP (cAMP)-independent using mutant cells which lack a functional Ras/cAMP signaling pathway. Alkalisation of medium also stimulated meiosis and sporulation in rich acetate medium, confirming our previous proposal that environmental alkalisation but not nitrogen limitation is a key condition for entry into meiosis and sporulation.

[Initial symptoms and mode of neurological progression in spinocerebellar ataxia type 6 (SCA6)]

Spinocerebellar ataxia type 6 (SCA6) is genetically defined as a group of SCA characterized by late-onset pure cerebellar ataxia clinically and by a small CAG repeat expansion in the gene encoding the alpha 1A-voltage-dependent-Ca channel subunit (CACNL1A4) on chromosome 19p13.1 genetically. We analyzed the initial symptoms and the mode of progression in this disorder on 25 genetically verified patients. The initial symptoms were recurrent episodes of transient vertigo (72%) or unsteady gait (28%). Neurologically, they showed apparent gaze-evoked nystagmus (92%), transient positional nystagmus (83%), and periodic alternating nystagmus (4%), in addition to cerebellar ataxia. In addition to these episodic symptoms, all patients developed progressive cerebellar ataxia over years. These fluctuating symptoms at the initial stage of the illness were clearly different from those of other SCA, rather overlapping with those of episodic ataxia type 2 (EA2), an allelic disorder of SCA6. The clinical similarity indicates that there might be a common mechanism at least in part causing these two disorders. The mode of progression and their neurological features were also presented.

[Periodic alternating nystagmus in spinocerebellar ataxia type 6 (SCA 6)]

We report a 61-year-old man with SCA 6 manifesting periodic alternating nystagmus (PAN). He first noted transient, recurrent episodes of "dizziness" at age 56. The symptom appeared several times a day, lasting for 3 years. At age 59, unsteady gait developed insidiously. On neurological examination, he showed limb and truncal ataxia, marked gaze nystagmus, and positional nystagmus. Thereafter, his ataxia became worse and PAN developed. Brain MRI showed pathologic atrophy which was confined to the cerebellum. PAN was rarely reported in spinocerebellar ataxia, being not described in SCA 6. The episodic "dizziness" at the initial stage has not gained much attention. Our observation indicates that the initial manifestation of SCA 6 overlaps with that of episodic ataxia type 2, an allelic disorder of SCA 6. PAN and fluctuating symptoms, as seen in our patient, must be carefully examined to see whether or not they can be parts of clinical presentations in SCA 6.

Multiple-step method for making exceptionally well-oriented liquid-crystalline sols of macromolecular assemblies

X-ray fiber diffraction is potentially powerful in solving the atomic structure of filamentous assemblies of macromolecules, as demonstrated for tobacco mosaic virus. However, it requires extremely well-oriented sols to allow for extraction of intensities on closely located layer-lines. A high degree of orientation requires a high filament concentration to restrain the orientational freedom, but orienting concentrated sols is hampered by their high viscosity. Here, we report a systematic method that reproducibly produces extremely good orientation, which involves three steps; liquid crystallization, centrifugation and magnetic orientation. We found that a slow centrifugation can trigger a dynamic self-orientation process to form perfectly homogeneous liquid-crystalline sols, and further centrifugation to concentrate sols followed by magnetic orientation produces exceptionally well-oriented sols. The best-oriented flagellar sol showed a disorientation angle of 0.6 degrees as 1sigma of its Gaussian distribution. The new method has been successfully applied to many other systems, such as tobacco mosaic virus and F-actin.