Proton-exchange mechanism of specific Cs+ adsorption via lattice defect sites of Prussian blue filled with coordination and crystallization water molecules

We have revealed the fundamental mechanism of specific Cs(+) adsorption into Prussian blue (PB) in order to develop high-performance PB-based Cs(+) adsorbents in the wake of the Fukushima nuclear accident. We compared two types of PB nanoparticles with formulae of Fe(III)4[Fe(II)(CN)6]3·xH2O (x = 10-15) (PB-1) and (NH4)0.70Fe(III)1.10[Fe(II)(CN)6]·1.7H2O (PB-2) with respect to the Cs(+) adsorption ability. The synthesised PB-1, by a common stoichiometric aqueous reaction between 4Fe(3+) and 3[Fe(II)(CN)6](4-), showed much more efficient Cs(+) adsorption ability than did the commercially available PB-2. A high value of the number of waters of crystallization, x, of PB-1 was caused by a lot of defect sites (vacant sites) of [Fe(II)(CN)6](4-) moieties that were filled with coordination and crystallization water molecules. Hydrated Cs(+) ions were preferably adsorbed via the hydrophilic defect sites and accompanied by proton-elimination from the coordination water. The low number of hydrophilic sites of PB-2 was responsible for its insufficient Cs(+) adsorption ability.

A rat model of human T lymphocyte virus type I (HTLV-I) infection. 1. Humoral antibody response, provirus integration, and HTLV-I-associated myelopathy/tropical spastic paraparesis-like myelopathy in seronegative HTLV-I carrier rats

Human T lymphocyte virus type I (HTLV-I) can be transmitted into several inbred strains of newborn and adult rats by inoculating newly established HTLV-I-immortalized rat T cell lines or the human T cell line MT-2. The transmission efficiency exceeds 80%, regardless of strain differences or the age at transmission. The production of anti-HTLV-I antibodies significantly differs among the strains and depends on the age at the time of transmission. Rats neonatally inoculated with HTLV-I-positive rat or human cells generally become seronegative HTLV-I carriers throughout their lives, whereas adult rats inoculated with HTLV-I-positive cells at 16 wk of age become seropositive HTLV-I carriers. The HTLV-I provirus genome is present in almost all organs, regardless of whether the carriers are seronegative or seropositive. According to antibody titers to HTLV-I, there are three groups of inbred rat strains: ACI, F344, and SDJ (high responders); WKA, BUF, and LEJ (intermediate responders); and LEW (low responder). Three of three 16-mo-old seronegative HTLV-I carrier rats of the WKA strain developed spastic paraparesis of the hind legs. Neuropathological examinations revealed that the lesions were confined primarily to the lateral and anterior funiculi of the spinal cord. Both myelin and axons were extensively damaged in a symmetrical fashion, and infiltration with massive foamy macrophages was evident. The most severe lesions were at levels of the thoracic cord and continued from the cervical to the lumbar area. These histopathological features as well as clinical symptoms largely parallel findings in humans with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). These HTLV-I carrier rats, in particular the WKA rats described above, can serve as a useful animal model for investigating virus-host interactions in the etiopathogenesis of HTLV-I-related immunological diseases, particularly HAM/TSP.

Meningo-encephalitis associated with HHV-6 related exanthem subitum

We report a 10-month-old boy with acute meningo-encephalitis associated with exanthem subitum. It has recently been reported that human herpesvirus-6 is the causative agent of exanthem subitum, and to our knowledge our case is the first report of meningo-encephalitis associated with HHV-6 infection.

Rat lymphoid cell lines with human T cell leukemia virus production. I. Biological and serological characterization

Cocultivation of spleen cells, lymph node cells, and thymocytes of female Wistar-King-Aptekman rats with short-term cultured male adult T cell leukemia (ATL) cells in the presence of 5-bromo-2'-deoxyuridine (BrdUrd) resulted in the establishment of rat lymphoid cell lines, TARS-1, TARL-2, and TART-1. Cytogenetic analysis of the three cell lines showed a female rat karyotype with 42 chromosomes. The surface phenotypes of TARS-1 and TART-1 were those of rat T cells. TARL-2 was only positive for rat Ia and leukocyte common antigens. The cell lines continuously produced a type C retrovirus, human T cell leukemia virus (HTLV) and expressed ATL-associated antigens. TARS-1 and TART-1, but not TARL-2 were transplantable into newborn syngeneic rats and nude mice. These results strongly indicate that HTLV not only immortalizes, but also transforms rat T cells in vitro. Adult rats immunized with either TARS-1 or TARL-2 produced antibodies specific for HTLV. The biochemical analysis of the antigens that reacted with rat sera revealed that they are the two HTLV-specific polypeptides, p24 and p28.

Analysis of mumps vaccine failure by means of avidity testing for mumps virus-specific immunoglobulin G

To characterize patients with mumps vaccine failure, avidity testing was performed with the Enzygnost Anti-Parotitis Virus/IgG kit using a single-dilution-6 M urea denaturation method. Five groups of patients were tested. Group 1 consisted of 29 patients with primary mumps infections; group 2 was 20 children and adults with a definite history of natural infection; group 3 was 7 patients with a recent mumps vaccination, 1 of whom developed parotid gland swelling and aseptic meningitis; group 4 was 14 patients with mumps vaccine failure; and group 5 was 6 patients with recurrent episodes of parotitis in addition to a history of vaccination. On the basis of the results of groups 1 and 2, an avidity of </=31% was determined to be low, and >/=32% was determined to be high. Avidity maturation from low to high appears to occur around 180 days after the acute illness. The results of group 3 showed that the vaccine-induced immunoglobulin G (IgG) had very low avidity. Among the 14 patients in group 4, 12 patients, including 7 with a positive IgM response, were diagnosed as having secondary vaccine failures. The results of group 5 suggested the possibility that the avidity of the mumps vaccine-induced IgG remains low or borderline. These results showed that secondary mumps vaccine failure occurs not infrequently, even among school age children under condition in which the vaccine coverage is low (i.e., 33% in our study population), and therefore, vaccinees are prone to be exposed to wild-type viruses. Avidity testing should provide information useful for the analysis of mumps virus infections.

Ocular manifestations of Kawasaki's disease (mucocutaneous lymph node syndrome)

In a prospective study of the ocular manifestations of Kawasaki's disease (mucocutaneous lymph node syndrome) in 18 children (11 boys and seven girls, ranging in age from 5 months to 9 years), we found bilateral injection of the bulbar conjunctiva in 16, bilateral iridocyclitis in 14, superficial punctate keratitis in four, vitreous opacities in two, papilledema in two, and subconjunctival hemorrhage in one. Conjunctival injection and iridocyclitis were always bilateral, and fellow eyes always had the same degree of inflammation. There were significant correlations between ocular inflammation and erythrocyte sedimentation rate (P less than .0001) and C-reactive protein level (P less than .0009). No serious ocular complications occurred.

Five measles virus antigens demonstrated by use of mouse hybridoma antibodies in productively infected tissue culture cells

Mouse hybridoma antibodies against 5 different structural components of measles virus were used in immune fluorescence tests to characterize the appearance of viral antigens in productively infected cell cultures. The antibodies employed in the tests reacted specifically with the hemagglutinin (H, 79K), polymerase (P, 72K), nucleocapsid (NP, 60K) hemolysin-fusion factor (F, 41+20K) and matrix (M, 36K) proteins. Syncytia formed in lytically infected cultures and single isolated cells in persistenly infected cell cultures were both examined. Antibodies against NP and P proteins stained cytoplasmic inclusions varying in size from small dots to more confluent masses, frequently in a perinuclear position. Nuclei of infected cells contained exclusively NP antigen. Antibodies to envelope components--H, F and M--stained cytoplasmic membrane structures and also gave a granular cytoplasmic staining, especially in syncytia. Although all persistently infected cells produced NP antigen and the associated P component, they had a restricted capacity to produce demonstrable amount of envelope antigens. The occurrence of cells containing envelope antigens varied between about 50 and 5 per cent with H and F antigens giving the highest and lowest frequence values, respectively. It is proposed that a restricted capacity of cells to produce biologically active fusion protein is a prerequisite for maintaining a persistent infection in actively dividing cells in vitro.

Non-thermal hot electrons ultrafastly generating hot optical phonons in graphite

Investigation of the non-equilibrium dynamics after an impulsive impact provides insights into couplings among various excitations. A two-temperature model (TTM) is often a starting point to understand the coupled dynamics of electrons and lattice vibrations: the optical pulse primarily raises the electronic temperature T(el) while leaving the lattice temperature T(l) low; subsequently the hot electrons heat up the lattice until T(el) = T(l) is reached. This temporal hierarchy owes to the assumption that the electron-electron scattering rate is much larger than the electron-phonon scattering rate. We report herein that the TTM scheme is seriously invalidated in semimetal graphite. Time-resolved photoemission spectroscopy (TrPES) of graphite reveals that fingerprints of coupled optical phonons (COPs) occur from the initial moments where T(el) is still not definable. Our study shows that ultrafast-and-efficient phonon generations occur beyond the TTM scheme, presumably associated to the long duration of the non-thermal electrons in graphite.

Ultrafast energy- and momentum-resolved dynamics of magnetic correlations in the photo-doped Mott insulator Sr2IrO4

Measuring how the magnetic correlations evolve in doped Mott insulators has greatly improved our understanding of the pseudogap, non-Fermi liquids and high-temperature superconductivity. Recently, photo-excitation has been used to induce similarly exotic states transiently. However, the lack of available probes of magnetic correlations in the time domain hinders our understanding of these photo-induced states and how they could be controlled. Here, we implement magnetic resonant inelastic X-ray scattering at a free-electron laser to directly determine the magnetic dynamics after photo-doping the Mott insulator Sr2IrO4. We find that the non-equilibrium state, 2 ps after the excitation, exhibits strongly suppressed long-range magnetic order, but hosts photo-carriers that induce strong, non-thermal magnetic correlations. These two-dimensional (2D) in-plane Néel correlations recover within a few picoseconds, whereas the three-dimensional (3D) long-range magnetic order restores on a fluence-dependent timescale of a few hundred picoseconds. The marked difference in these two timescales implies that the dimensionality of magnetic correlations is vital for our understanding of ultrafast magnetic dynamics.

Epidemiology of influenza-associated encephalitis-encephalopathy in Hokkaido, the northernmost island of Japan

BACKGROUND

It is well known that acute onset brain dysfunction, which usually is diagnosed as encephalitis or encephalopathy, occurs in association with influenza. However, this may have been underestimated as a rather infrequent event. Sixty-four infants and children developed encephalitis-encephalopathy during the five recent influenza seasons in Hokkaido, the northernmost island of Japan.

METHODS

Inquiries were sent at the end of each season, from October 1994 to March 1999, to 94 hospitals and institutes in Hokkaido which accept pediatric age patients, asking if there were any admitted cases of encephalitis or encephalopathy.

RESULTS

The patients were 42 boys and 22 girls and 47 (73.4%) were 4 years of age or younger. None of them had received an influenza vaccine nor had an oral administration of aspirin. Most of the patients became comatose with or without convulsions within a few days of the onset of fever. Twenty-eight (43.8%) patients died and 13 (20.3%) had neurological sequelae. Patients with clotting disorders, elevations of serum creatine kinase and/or aspartate aminotransferase and alanine aminotransferase, and brain CT abnormalities had a poor prognosis compared with patients without. Among these affected patients, the influenza genome (H3) was detected by polymerase chain reaction in nine cerebrospinal fluid samples, influenza virus A (H3N2) was isolated in 18 nasopharyngeal swab samples and a four-fold or greater rise in serum hemagglutinin inhibition antibody titer against H3N2 was observed in seven patients.

CONCLUSIONS

It appears urgent to promote vaccination against influenza in young children to prevent these devastating disease conditions.

Close association between pulmonary disease manifestation in Mycoplasma pneumoniae infection and enhanced local production of interleukin-18 in the lung, independent of gamma interferon

To investigate pathophysiologies of Mycoplasma pneumoniae infection from an immunological point of view, we measured the levels of interleukin-18 (IL-18) (originally designated gamma interferon [IFN-gamma]-inducing factor) in 19 serum samples from 10 patients with pneumonia without pleural effusion (ages 1 to 16 years), 3 serum and 13 pleural fluid samples from 11 patients with pleural effusions (ages 11 months to 15 years), and 18 serum and 27 cerebrospinal fluid samples from 24 patients with central nervous system complications (ages 1 to 15 years). IL-18 was measured by a commercially available enzyme-linked immunosorbent assay kit (MBL, Nagoya, Japan). In addition, the levels of tumor necrosis factor alpha, IFN-gamma, IL-6, IL-12, and KL-6 (a mucin-like glycoprotein expressed on type 2 pneumocytes) were measured in selected samples. The results concerning pleural effusions showed that elevated levels of IL-18 in pleural fluid, but not in serum, were solely associated with a sustained fibrotic change of the lung on chest roentgenography which might represent a pathological feature of intraluminal organization. All the pleural fluid samples with elevated levels of IL-18 were positive by PCR for M. pneumoniae DNA. There was no association between IL-18 and IFN-gamma levels in serum or in the pleural fluid. On the other hand, elevated levels of IL-18 in serum, but not in cerebrospinal fluid samples, were observed in the cases complicated by central nervous system involvement, including profound brain dysfunction with seizures. Our study demonstrated that M. pneumoniae can induce IL-18 and that the enhanced local production of IL-18 in the lung is closely associated with pulmonary disease manifestation.

Interleukin-6 in cerebrospinal fluid of patients with central nervous system infections

Interleukin(IL)-6 levels were measured in cerebrospinal fluid (CSF) and serum samples from pediatric patients with central nervous system (CNS) infections by means of an enzyme-linked immunosorbent assay. Mean IL-6 concentrations in CSF samples from patients with bacterial meningitis (49,017 +/- 44,730 pg/ml) were significantly higher than those in patients with aseptic meningitis (1076 +/- 1572 pg/ml) or encephalitis (409 +/- 835 pg/ml). In aseptic meningitis and encephalitis, IL-6 levels in serum were within the lower ranges (< 100 pg/ml), in contrast with the highly elevated levels found in bacterial meningitis (14,332 +/- 18,385 pg/ml). In 5 of the 15 patients with encephalitis, elevated levels of IL-6 were observed in the initial CSF samples despite normal findings of routine CSF examinations. Also, sequential CSF samples revealed that there was an increase in the CSF cell count in two of the five patients. These results validated the potential of measuring IL-6 in CSF samples for the purpose of providing additional information on routine laboratory test results.

Orbital-dependent modifications of electronic structure across the magnetostructural transition in BaFe2As2

Laser angle-resolved photoemission spectroscopy (ARPES) is employed to investigate the temperature (T) dependence of the electronic structure in BaFe2As2 across the magnetostructural transition at T{N} approximately 140 K. A drastic transformation in Fermi surface (FS) shape across T{N} is observed, as expected by first-principles band calculations. Polarization-dependent ARPES and band calculations consistently indicate that the observed FSs at k{z} approximately pi in the low-T antiferromagnetic state are dominated by the Fe3d{zx} orbital, leading to the twofold electronic structure. These results indicate that magnetostructural transition in BaFe2As2 accompanies orbital-dependent modifications in the electronic structure.

Survey of mycoplasmal bacteremia detected in children by polymerase chain reaction

To determine whether mycoplasmal bacteremia occurs during ordinary or complicated diseases due to M. pneumoniae (and if so, how frequently), we used polymerase chain reaction (PCR) to detect M. pneumoniae in serum samples. The PCR primers used were modified for nested amplification. The genome of this organism was detected in 1 of the 25 patients with pneumonia and 10 of the 17 patients without pneumonia (P < .001, chi test). The genome was detected more frequently in patients who had encephalitis of which the neurological onset was within 7 days of the onset of fever rather than later. We hypothesize that mycoplasmal bacteremia occurs more frequently than previously appreciated, specifically in the absence of pneumonia, and that certain types of complications (e.g., encephalitis of early onset) are associated with its occurrence.

Second-harmonic generation from a KBe(2) BO(3)F(2) crystal in the deep ultraviolet

By use of KBe(2)BO(3)F(2) (KBBF) crystal with a size of 10 mmx10 mm x1.2 mm and a special prism-coupling technique (PCT), fourth-harmonic generation of Ti:sapphire laser systems from 200 to 179.4 nm has been achieved. Moreover, with a Ti:sapphire laser with a 50-fs pulse duration and a 1-kHz repetition rate, conversion efficiency as high as 13% from 400 to 200 nm without any surface-loss correction has also been obtained. The data show that with the PCT a KBBF crystal can produce deep-UV coherent light with measurable power output.

Photoemission spectroscopic evidence of gap anisotropy in an f-electron superconductor

We used low-temperature ultrahigh-resolution (360 microeV) photoemission spectroscopy with a laser as a photon source (Laser-PES) to study the superconducting (SC) gap of an f-electron superconductor CeRu2. The unique combination of the large escape depth expected from the known universal behavior and extremely high-energy resolution has enabled us to directly measure the bulk SC gap of an f-electron superconductor for the first time. The present study provides direct evidence for an anisotropic SC gap in CeRu2, and also demonstrates the potential of Laser-PES in investigating unconventional superconductivity realized in correlated d- and f-electron superconductors.

Generation of 0.66-TW pulses at 1 kHz by a Ti:sapphire laser

A 1-kHz, 0.66-TW Ti:sapphire laser has been developed. We obtained 21-fs, 14-mJ pulses with an extraction efficiency of 32% in the final amplifier. The dispersion through the system was successfully compensated for by insertion of a pair of prisms in a regenerative amplifier. The pulses were characterized by frequency-resolved optical gating and were in good agreement with dispersion calculated by three-dimensional ray tracing.

Time-resolved photoemission apparatus achieving sub-20-meV energy resolution and high stability

The paper describes a time- and angle-resolved photoemission apparatus consisting of a hemispherical analyzer and a pulsed laser source. We demonstrate 1.48-eV pump and 5.92-eV probe measurements at the ⩾10.5-meV and ⩾240-fs resolutions by use of fairly monochromatic 170-fs pulses delivered from a regeneratively amplified Ti:sapphire laser system operating typically at 250 kHz. The apparatus is capable to resolve the optically filled superconducting peak in the unoccupied states of a cuprate superconductor, Bi2Sr2CaCu2O(8 + δ). A dataset recorded on Bi(111) surface is also presented. Technical descriptions include the followings: A simple procedure to fine-tune the spatio-temporal overlap of the pump-and-probe beams and their diameters; achieving a long-term stability of the system that enables a normalization-free dataset acquisition; changing the repetition rate by utilizing acoustic optical modulator and frequency-division circuit.

Genetic loci controlling susceptibility to gamma-ray-induced thymic lymphoma

BALB/c is a susceptible strain for the development of gamma-ray induced mouse thymic lymphoma whereas MSM shows resistance. Association analysis of 220 backcross mice between the two strains using 67 markers was carried out to identify loci involved in the control of susceptibility. The genotype of mice with lymphoma showed excess heterozygosity relative to MSM homozygosity at D2Mit15 and D4Mit12 and was skewed toward MSM-derived alleles at D5Mit5. The P values in Mantel-Cox test were 0.0048 (D2Mit15), 0.0034 (D4Mit12) and 0.0048 (D5Mit5), suggesting association at the three loci in the susceptibility. Cooperative effect on lymphomagenesis was also observed among the three loci. To obtain independent evidence for linkage at D4Mit12, we made partially congenic mice in which a D4Mit12 region in BALB/c was replaced by MSM-derived homolog. Examination for the lymphoma susceptibility in 78 progeny of the congenic mice confirmed the effect of the locus near D4Mit12 (P=0.0037). The result, together with the linkage analysis, shows that the locus near D4Mit12 is regarded as a confirmed linkage but the other two loci as marginally suggestive.