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We have constructed a soft X-ray diffractometer with a 7.5-T superconducting magnet in order to study ordered electronic structures under high magnetic field. In this paper, we present the features of this system and an example of resonant soft X-ray scattering measurement under the magnetic field of (LaMnO3)3(SrMnO3)3 superlattice with a remarkable negative magnetoresistance effect.

The cmpABCD operon of Synechococcus sp. strain PCC 7942, encoding a high-affinity bicarbonate transporter, is transcribed only under CO 2 -limited conditions. In Synechocystis sp. strain PCC 6803, the slr0040, slr0041, slr0043 , and slr0044 genes, forming an operon with a putative porin gene ( slr0042 ), were identified as the cmpA, cmpB, cmpC , and cmpD genes, respectively, on the basis of their strong similarities to the corresponding Synechococcus cmp genes and their induction under low CO 2 conditions. Immediately upstream of and transcribed divergently from the Synechocystis cmp operon is a gene ( sll0030 ) encoding a homolog of CbbR, a LysR family transcriptional regulator of the CO 2 fixation operons of chemoautotrophic and purple photosynthetic bacteria. Inactivation of sll0030 , but not of another closely related cbbR homolog ( sll1594 ), abolished low CO 2 induction of cmp operon expression. Gel retardation assays showed specific binding of the Sll0030 protein to the sll0030-cmpA intergenic region, suggesting that the protein activates transcription of the cmp operon by interacting with its regulatory region. A cbbR homolog similar to sll0030 and sll1594 was cloned from Synechococcus sp. strain PCC 7942 and shown to be involved in the low CO 2 -induced activation of the cmp operon. We hence designated the Synechocystis sll0030 gene and the Synechococcus cbbR homolog cmpR . In the mutants of the cbbR homologs, upregulation of ribulose-1,5-bisphosphate carboxylase/oxygenase operon expression by CO 2 limitation was either unaffected (strain PCC 6803) or enhanced (strain PCC 7942), suggesting existence of other low CO 2 -responsive transcriptional regulator(s) in cyanobacteria.

In recent years, time-resolved spectroscopy systems using near infrared pulsed laser have been applied to develop optical computed tomography. We applied this technique to measure the optical properties of osseous tissues. First, we gradually demineralized 10 mm blocks of bovine trabecular bone with EDTA, maintaining the absorption characteristics and structure but varying the hydroxyapatite content, thus creating specimens differing only in light scattering properties. We used computer densitograms to assess light penetration, and analyzed the correlation with bone mineral density (BMD) as with dual-energy X-ray absorptiometry scans. The light penetration increased with decreasing BMD. Second, using the above-mentioned pulsed laser time-resolved spectroscopy system, we investigated the correlation between the BMD and the time response waveforms of 10-mm blocks of bovine cortical bone, trabecular bone, and surrounding tissue as well as human trabecular bone. The human lumbar vertebral bone also displayed an inverse correlation between BMD and maximum light penetration and a positive correlation between BMD and peak time delay. This is the first demonstration of a correlation between BMD and light scattering properties showing that BMD can indeed be measured with light. Our results show the possibility of obtaining information on internal bone structure and composition in vivo through assessment of the waveforms obtained by a time-resolution system in the near infrared region.

A method for the quantitation of polycyclic aromatic hydrocarbons (PAHs) in indoor and outdoor air by high-performance liquid chromatography (HPLC) with a spectrofluorometric detection and programmed excitation and emission wavelength pairs is proposed. The mobile phase is a linear gradient of methanol-water. The relative standard deviations (n = 5) are in the range 0.38-1.7% at concentration levels of 0.69-11.40 ng ml(-1). The determination limits (S N = 10 ) are 0.5-15.9 pg. The proposed method was successfully applied to quantitate 12 PAHs in gas phase and particulates in indoor and outdoor air. The recoveries of PAHs from gas phase and particulates were 95.7-117.5 and 94.8-112.4%, respectively. This highly sensitive automatic HPLC analysis for PAHs both in gas phase and particulates can be applied to indoor and outdoor survey.

BackgroundPandemic influenza A(H1N1) virus infection quickly circulated worldwide in 2009. In Japan, the first case was reported in May 2009, one month after its outbreak in Mexico. Thereafter, A(H1N1) infection spread widely throughout the country. It is of great importance to profile and understand the situation regarding viral mutations and their circulation in Japan to accumulate a knowledge base and to prepare clinical response platforms before a second pandemic (pdm) wave emerges.MethodologyA total of 253 swab samples were collected from patients with influenza-like illness in the Osaka, Tokyo, and Chiba areas both in May 2009 and between October 2009 and January 2010. We analyzed partial sequences of the hemagglutinin (HA) and neuraminidase (NA) genes of the 2009 pdm influenza virus in the collected clinical samples. By phylogenetic analysis, we identified major variants of the 2009 pdm influenza virus and critical mutations associated with severe cases, including drug-resistance mutations.Results and conclusionsOur sequence analysis has revealed that both HA-S220T and NA-N248D are major non-synonymous mutations that clearly discriminate the 2009 pdm influenza viruses identified in the very early phase (May 2009) from those found in the peak phase (October 2009 to January 2010) in Japan. By phylogenetic analysis, we found 14 micro-clades within the viruses collected during the peak phase. Among them, 12 were new micro-clades, while two were previously reported. Oseltamivir resistance-related mutations, i.e., NA-H275Y and NA-N295S, were also detected in sporadic cases in Osaka and Tokyo.

The structural and electrical properties of a metal-halide cubic perovskite, CH(3)NH(3)SnI(3), have been examined. The band structure, obtained using first-principles calculation, reveals a well-defined band gap at the Fermi level. However, the temperature dependence of the single-crystal electrical conductivity shows metallic behavior down to low temperatures. The temperature dependence of the thermoelectric power is also metallic over the whole temperature range, and the large positive value indicates that charge transport occurs with a low concentration of hole carriers. The metallic properties of this as-grown crystal are thus suggested to result from spontaneous hole-doping in the crystallization process, rather than the semi-metal electronic structure. The present study shows that artificial hole doping indeed enhances the conductivity.

Background Small RNA attracts increasing interest based on the discovery of RNA silencing and the rapid progress of our understanding of these phenomena. Although recent studies suggest the possible existence of yet undiscovered types of small RNAs in higher organisms, many studies to profile small RNA have focused on miRNA and/or siRNA rather than on the exploration of additional classes of RNAs. Results Here, we explored human small RNAs by unbiased sequencing of RNAs with sizes of 19–40 nt. We provide substantial evidences for the existence of independent classes of small RNAs. Our data shows that well-characterized non-coding RNA, such as tRNA, snoRNA, and snRNA are cleaved at sites specific to the class of ncRNA. In particular, tRNA cleavage is regulated depending on tRNA type and tissue expression. We also found small RNAs mapped to genomic regions that are transcribed in both directions by bidirectional promoters, indicating that the small RNAs are a product of dsRNA formation and their subsequent cleavage. Their partial similarity with ribosomal RNAs (rRNAs) suggests unrevealed functions of ribosomal DNA or interstitial rRNA. Further examination revealed six novel miRNAs. Conclusion Our results underscore the complexity of the small RNA world and the biogenesis of small RNAs.

Comparative morphological studies on epididymal fat cells from young, old and obese rats were made by scanning and freeze-fracture electron microscopies. Scanning microscopy showed that adipocytes of young rats were spherical with a smooth surface, but with a few crater-like pits. As the rats became older, their fat cells increased in size and the surface of the cells became rough with an increase in the number of craters. In obese rats, there were more numerous craters in various sizes than in old rats. In ultra-thin sections, the accumulated lipid of adipocytes appeared uniform and amorphous. But in freeze-fractured adipocytes of young and old rats the central lipid was seen to have a multi-lamellar structure, like an onion. The fracture-face of lipid droplets in adipocytes from the obese rat was disfigured and complicated by the crossing of membranous lamellae. These findings suggest that the modes of lipid accumulation in the fat cells of old rats and obese rats differ. This difference may be related to the difference in the distributions and numbers of craters on the surface of adipocytes in these animals.

Endogenous lipid droplets were prepared by subjecting fat cells to hypotonic shock and to Triton X-100 treatment. The structure of the endogenous lipid droplet fraction was examined by scanning and transmission electron microscopies. Neither intact fat cells nor disrupted cell membranes were detectable in the endogenous lipid droplet fraction. With this endogenous substrate, epinephrine elicited lipolysis with either hormone-sensitive lipase or lipoprotein lipase, but no cyclic AMP-protein kinase mediated stimulation of lipolysis was observed. On the other hand, epinephrine did not stimulate lipolysis when triolein emulsified with arabic gum was used as substrate. With the latter exogenous substrate, however, cyclic AMP-protein kinase was found to stimulate lipolysis with hormone-sensitive lipase as enzyme. These results agree with the proposal of Wise and Jungas that the epinephrine-stimulated increase of hydrolysis of endogenous fat is not mediated through cyclic AMP-protein kinase. A possible mechanism of hydrolysis of endogenous fat by induction of lipolysis by epinephrine in fat cells is discussed.

Marked delay of fat absorption was observed in choline-deficient rats. The morphology of intestinal epithelial cells of choline-deficient rats was examined during fat absorption. By light microscopy, numerous lipid droplets remained in the apical zone of absorptive cells even 3hr after fat feeding. Ultracytochemically, the apical plasma membrane of these cells showed irregular microvilli with bleb formation and the Mg-ATPase and K-NPPase activities in the surface epithelium were decreased. Furthermore, absorptive cells in the choline-deficient state showed reduced Ca-ATPase (myosin ATPase) activity in the terminal web and other filamental bundles in close proximity to secretory vesicles throughout the cytoplasm. These findings were associated with poorly developed, disorganized microfilaments between the intracellular organelles and numerous large lipid droplets throughout the cytoplasm of absorptive cells. These lipid droplets often fused with each other and were large and irregular in shape near the Golgi complex. These observations indicate an altered state of contraction of microfilaments, accounting for impaired intracellular transport and discharge of chylomicrons by the intestine in choline-deficient rats.

The effect of insulin on the surface structure of isolated adipocytes was examined by scanning electron microscopy. Scanning electron microscopy showed that control cells had a smooth spherical surface, with a very few hemispherical projections of 1μm diameter. Thin-section transmission electron microscopy of the projections showed that they consisted of lipid droplets covered by a thin cytoplasmic matrix. On treatment with insulin, the number of these projections increased, and the optimal concentration of insulin caused a ten-fold increase in the number of cells with projections and the number of projections per cell. The number of projections decreased when the adipocytes were treated with phospholipase C or washed with buffer during lipogenesis with insulin. These observations may help in interpretation of biochemical data on the insulin receptor on the surface of adipocytes.

The effect of amino acids on insulin responsiveness in epididymal adipose tissue was examined. It was found that insulin-stimulated glucose oxidation in fat cells was significantly inhibited by glycine, alanine, valine, leucine, isoleucine, cysteine, methionine, lysine, phenylalanine, and proline. The effect of insulin on glucose incorporation into triglyceride is also severely diminished by these amino acids. In addition, alanine reduced the incorporation of precursors ([U-14C]glucose or [1-14C]palmitate) into triglyceride both in vitro and in vivo. The Ki values of alanine were 0.4 and 0.5 mM toward the precursors of glucose and palmitate, respectively. The mechanism of reduction of insulin responsiveness in rat adipose tissue is discussed on the basis of these results.

Transfer of lipid to the lymph by the intestine was studied in rats fed on choline-deficient or choline-supplemented diet for 2 weeks. In choline-deficient rats, lymph output was reduced. Choline deficiency impaired the incorporation of glycerol tri[1-14C]oleate into triglyceride in the lymph. The triglyceride level in lymph lipoproteins was lower in choline-deficient rats than in controls. Ultrastructural studies suggested that impaired release of lipoproteins was responsible for accumulation of fat in intestinal absorptive cells. These defects are probably related to changes in the membrane system of the intestine and to a failure in lipid droplet movement within absorptive cells, resulting from alterations in the microfilaments. Oral administration of phosphatidylcholine to rats on choline-deficient diet rapidly improved the decreased lymph output and the impaired incorporation of glycerol tri[1-14C]oleate into triglyceride and reduced fat deposition in intestinal epithelial cells. In conclusion, phospholipids such as choline are confirmed as being extremely important in the absorption of fat by the possible mechanism of fat transport across the membrane.

Recently, the production of commercial frozen-stored foods has been increased. However, no investigation has been reported on the lipoper-oxide included in frozen-stored foods in the market.The level of lipoperoxide on 58 kinds of commercial foods was investigated: commercial frozen-stored foods (29 kinds), canned provisions (17 kinds) and dried fishes (12 kinds).The results obtained are shown in Table 1-3. In Table 1, the level of lipoperoxide was found to be increased as their storage time increases. The level of lipoperoxide of dried fishes were higher than those of the other samples.

Background Painful diabetic neuropathy (PDN) is a serious complication of diabetes mellitus that affects a large number of patients in many countries. The molecular mechanisms underlying the exaggerated nociception in PDN have not been established. Recently, duloxetine (DLX), a serotonin and noradrenaline re-uptake inhibitor, has been recommended as one of the first-line treatments of PDN in the United States Food and Drug Administration, the European Medicines Agency and the Japanese Guideline for the Pharmacologic Management of Neuropathic pain. Because selective serotonin re-uptake inhibitors show limited analgesic effects in PDN, we examined whether the potent analgesic effect of DLX contributes toward improving the pathologically aberrant noradrenaline homeostasis in diabetic models. Results In streptozotocin (STZ) (50 mg/kg, i.v.)-induced diabetic rats that exhibited robust mechanical allodynia and thermal hyperalgesia, DLX (10 mg/kg, i.p.) significantly and markedly increased the nociceptive threshold. The analgesic effect of DLX was nullified by the prior administration of N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4) (50 mg/kg, i.p.), which drastically eliminated dopamine-beta-hydroxylase- and norepinephrine transporterimmunopositive fibers in the lumbar spinal dorsal horn and significantly reduced the noradrenaline content in the lumbar spinal cord. The treatment with DSP-4 alone markedly lowered the nociceptive threshold in vehicle-treated non-diabetic rats; however, this pro-nociceptive effect was occluded in STZ-treated diabetic rats. Furthermore, STZ-treated rats exhibited a higher amount of dopamine-beta-hydroxylase- and norepinephrine transporterimmunopositive fibers in the dorsal horn and noradrenaline content in the spinal cord compared to vehicle-treated rats. Conclusions Impaired noradrenaline-mediated regulation of the spinal nociceptive network might underlie exaggerated nociception in PDN. DLX might exert its analgesic effect by selective enhancement of noradrenergic signals, thus counteracting this situation.

SummaryMemory is thought to be stored in the brain as an ensemble of cells activated during learning. Although optical stimulation of a cell ensemble triggers the retrieval of the corresponding memory, it is unclear how the association of information occurs at the cell ensemble level. Using optogenetic stimulation without any sensory input in mice, we found that an artificial association between stored, non-related contextual, and fear information was generated through the synchronous activation of distinct cell ensembles corresponding to the stored information. This artificial association shared characteristics with physiologically associated memories, such as N-methyl-D-aspartate receptor activity and protein synthesis dependence. These findings suggest that the association of information is achieved through the synchronous activity of distinct cell ensembles. This mechanism may underlie memory updating by incorporating novel information into pre-existing networks to form qualitatively new memories.