Temporal change of 236U/238U and 235U/238U isotopic ratios in atmospheric deposition in Tokyo and Akita from 1963 to 1979.

We examine the temporal changes of 236U/238U and 235U/238U in atmospheric deposition from samples collected in Tokyo and Akita from 1963 to 1979 and elucidate the spatial distribution and historical changes of the anthropogenic sources of uranium in Japan. The 236U/238U ratio of atmospheric deposition in Tokyo peaked in 1963 and again during the 1970s, while the corresponding 235U/238U ratios of atmospheric deposition during the second peak period were lower than that of natural uranium. The 236U/238U ratios of atmospheric deposition in Akita samples peaked in 1963. The 235U/238U ratios in Akita samples were almost identical to that of the natural uranium ratios. These results suggest that the peak of 236U/238U in 1963 corresponds to what is recognized as representative for global fallout. The increase of 236U/238U and the decrease of 235U/238U observed simultaneously in the 1970s indicate that depleted uranium has subsequently been released into the environment around Tokyo. The cumulative deposition density of 236U for atmospheric fallout samples collected in Tokyo from 1968 to 1979 is an order of magnitude larger than that of the global fallout, suggesting that the depleted uranium in the 1970s is a major component of 236U in Tokyo and should be considered as an end-member when using 236U as an environmental tracer in the industrial city. This knowledge can facilitate future research using 236U as an effective environmental tracer.

Optimization of triacylglycerol and starch production in Chlamydomonas debaryana NIES-2212 with regard to light intensity and CO2 concentration.

Triacylglycerol (TAG) and starch produced by micro-algae are potential sources of biofuel. Our previous studies showed that the unicellular green alga, Chlamydomonas debaryana NIES-2212, which is a rare species of Chlamydomonas that possesses phosphatidylcholine (PC), is a seed organism for the development of biofuel producers. This alga accumulates large amounts of TAG and starch under completely photo-autotrophic conditions during stationary phase without nutrient deprivation. The present study was performed to optimize the growth conditions of this alga with regard to light intensity and CO2 concentration to improve the efficiency of TAG and starch production. The growth rate of C. debaryana was greater at higher light intensity, although there was no significant difference in the final cell density of the culture. The highest contents of TAG and starch, approximately 200 fmol cell-1 and 600 pg cell-1, respectively, were achieved with a light intensity of 200 µmol m-2 s-1 bubbled with air containing 5.0 % CO2. These results suggest that optimization of light intensity and CO2 concentration can enhance the productivity of TAG and starch by C. debaryana NIES-2212.

Soy isoflavones inducing overt hypothyroidism in a patient with chronic lymphocytic thyroiditis: a case report.

BACKGROUND: Many people have thyroid conditions that make them susceptible to hypothyroidism. If the foods they eat may interfere with the production of thyroid hormone, which can lead to development of serious hypothyroidism. The danger of health drinks should always be noted. CASE PRESENTATION: A 72-year-old Japanese woman was previously diagnosed with chronic lymphocytic thyroiditis caused by a goiter and had an elevated thyroid-stimulating hormone level (6.56 µIU/ml), a high anti-thyroid peroxidase antibody level (>600 IU/ml), and a high antithyroglobulin level (> 4000 IU/ml) but normal levels of free triiodothyronine (3.08 pg/ml) and thyroxine (1.18 ng/ml). She presented to our hospital with sudden-onset general malaise, edema, and hoarseness with an elevated thyroid-stimulating hormone (373.3 µIU/ml) level and very low triiodothyronine (< 0.26 pg/ml) and thyroxine (0.10 ng/ml) levels. It was determined that for 6 months she had been consuming a processed, solved health drink ("barley young leaf") in amounts of 9 g/day, which included soybean and kale powder extract. Hypothyroidism might be affected by ingredients of health drinks. She discontinued consumption of the health drink immediately and began taking 12.5 µg of levothyroxine. The amount of levothyroxine was gradually increased every 3 days up to 100 µg. At day 61, her thyroid-stimulating hormone level had decreased (6.12 µIU/ml), her free triiodothyronine (2.69 pg/ml) and thyroxine (1.56 ng/ml) levels had increased, and her general condition was improved. Among risky foods lowering thyroid function, some experimental studies have revealed that isoflavones reduce thyroid function. Therefore, we measured the presence of isoflavones in the patient's frozen serum with thin-layer chromatography. After she discontinued consumption of the health drink, two components quickly disappeared, and the other three components gradually decreased. On the basis of developing solvent composition and a positive ferric chloride reaction in thin-layer chromatography experiment, the five ingredients that disappeared or decreased were highly suspected to be soy isoflavones. CONCLUSIONS: This case emphasizes that consuming health drinks that include soy isoflavone powder extracts can lead to severe hypothyroidism.

Revisiting the theoretical basis of the endosymbiotic origin of plastids in the original context of Lynn Margulis on the origin of mitosing, eukaryotic cells.

Fifty years ago, Lynn Margulis proposed a comprehensive hypothesis on the origin of eukaryotic cells with an emphasis on the origin of mitosis. This hypothesis postulated that the eukaryotic cell is a composite of different parts as a result of the symbiosis of various different bacteria. In this hypothesis, she integrated previously proposed ideas that mitochondria and chloroplasts were descendants of endosymbionts that originated from aerobic bacteria and blue-green algae (now cyanobacteria), respectively. However, the major part of her hypothesis, which she believed to be original, was the origin of mitosis. The core of her postulate involved a chromosome partition mechanism dependent on DNA-microtubule binding, which originated from a hypothetical centriole-DNA complex, with an ability to replicate. Surprisingly, her complete lack of real experimental works in the cytoskeleton, cell motility, or paleontology did not prevent this 29-year-old junior scientist from assembling archival knowledge and constructing a narrative on the evolution of all organisms. Whether the centriole-DNA complex originated from a spirochete or not was a minor anecdote in this initial postulate. Unfortunately, this hypothesis on the origin of mitosis, which she believed to be a holistic unity, testable by experiments, was entirely refuted. Despite falsification of her original narrative as a whole, her success as a founder of endosymbiotic theory on the origin of mitochondria and chloroplasts is undoubted. We will discuss the reasons for her success in terms of the historical situation in the latter half of the 20th century.

Detailed identification of fatty acid isomers sheds light on the probable precursors of triacylglycerol accumulation in photoautotrophically grown Chlamydomonas reinhardtii.

Chlamydomonas reinhardtii is a model alga for studying triacylglycerol (TAG) accumulation in the photosynthetic production of biofuel. Previous studies were conducted under photoheterotrophic growth conditions in medium supplemented with acetate and/or ammonium. We wanted to demonstrate TAG accumulation under truly photoautotrophic conditions without reduced elements. We first reidentified all lipid components and fatty acids by mass spectrometry, because the currently used identification knowledge relies on data obtained in the 1980s. Accordingly, various isomers of fatty acids, which are potentially useful in tracing the flow of fatty acids leading to the accumulation of TAG, were detected. In strain CC1010 grown under photoautotrophic conditions, TAG accumulated to about 57.5 mol% of total lipids on a mole fatty acid basis after the transfer to nitrogen-deficient conditions. The content of monogalactosyl diacylglycerol, sulfoquinovosyl diacylglycerol, and phosphatidylglycerol decreased drastically. The accumulated TAG contained 16:0 as the major acid and 16:4(4,7,10,13), 18:2(9,12), and 18:3(9,12,15), which are typically found in chloroplast lipids. Additionally, 18:1(11) and 18:3(5,9,12), which are specific to extrachloroplast lipids, were also abundant in the accumulated TAG. Photosynthesis and respiration slowed markedly after the shift to nitrogen-deficient conditions. These results suggest that fatty acids for the production of TAG were supplied not only from chloroplast lipids but also from other membranes within the cells, although the possibility of de novo synthesis cannot be excluded. Under nitrogen-replete conditions, supplementation with a high concentration of CO2 promoted TAG production in the cells grown photoautotrophically, opening up the possibility to the continuous production of TAG using CO2 produced by industry.

In situ conductance measurements of copper phthalocyanine thin film growth on sapphire [0001].

The current flowing through a thin film of copper phthalocyanine vacuum deposited on a single crystal sapphire [0001] surface was measured during film growth from 0 to 93 nm. The results, expressed as conductance vs. nominal film thickness, indicate three distinct film growth regions. Conductive material forms below about 5 nm and again above 35 nm, but in the intermediate thicknesses the film conductance was observed to decrease with increasing film thickness. With the aid of ac-AFM topology images taken ex situ, the conductance results are explained based on the Stranski-Krastanov (2D + 3D) film growth mechanism, in which the formation of a thin wetting layer is followed by the growth of discrete islands that eventually coalesce into an interpenetrating, conductive network.

Acute phase response of selenium status and glutathione peroxidase activity in blood plasma before and after total knee arthroplasty surgery.

Several studies show the consistent results of the decrease in plasma or serum selenium (Se) after surgery, and the change is suggested to be a negative acute phase response of Se to the surgical inflammation. Plasma glutathione peroxidase (GPx), which is included in the acute phase response proteins, is a selenoenzyme. However, previous studies failed to show any changes in GPx activity before and after surgery. In the present study, we investigated the Se- and selenoenzyme responses that accompany the acute inflammatory reactions during and following major surgery. Patients who underwent elective total knee arthroplasty surgery due to knee osteoarthritis at the Department of Orthopaedic Surgery at Gunma University Hospital in Japan were studied. The plasma Se concentration was determined, and the activity of plasma GPx was measured. C-reactive protein (CRP), albumin, blood urea nitrogen (BUN), and white blood cell (WBC) count were also analysed. Increases in the inflammatory biomarkers of CRP and WBC showed inflammatory reactions with the surgery. A significant increase in plasma GPx activity (p < 0.05) and decreases in the plasma Se concentration (p < 0.05) and in serum albumin (p < 0.05) after surgery were observed. Since albumin is a Se-containing protein and represents a negative acute phase protein that provides amino acids for the production of other series of acute phase proteins, the present results suggest that there is a redistribution of plasma Se to GPx that occurs as an acute phase response, and the source of Se for GPx could be, at least partly, from albumin.

Dynamic morphologies of pollen plastids visualised by vegetative-specific FtsZ1-GFP in Arabidopsis thaliana.

The behaviour and multiplication of pollen plastids have remained elusive despite their crucial involvement in cytoplasmic inheritance. Here, we present live images of plastids in pollen grains and growing tubes from transgenic Arabidopsis thaliana lines expressing stroma-localised FtsZ1-green-fluorescent protein fusion in a vegetative cell-specific manner. Vegetative cells in mature pollen contained a morphologically heterogeneous population of round to ellipsoidal plastids, whilst those in late-developing (maturing) pollen included plastids that could have one or two constriction sites. Furthermore, plastids in pollen tubes exhibited remarkable tubulation, stromule (stroma-filled tubule) extension, and back-and-forth movement along the direction of tube growth. Plastid division, which involves the FtsZ1 ring, was rarely observed in mature pollen grains.

Biotin status affects nickel allergy via regulation of interleukin-1beta production in mice.

Biotin, a water-soluble B complex vitamin, is possibly involved in chronic inflammatory diseases, although the detailed mechanisms are unclear. In this study, we investigated the effects of biotin status on nickel (Ni) allergy in mice. Mice were fed a basal or biotin-deficient (BD) diet for 8 wk and sensitized with an intraperitoneal injection of NiCl(2) and lipopolysaccharide. Ten days after sensitization, NiCl(2) was intradermally injected into pinnas and ear swelling was measured. For in vitro analysis, we cultured a murine macrophage cell line, J774.1, under a biotin-sufficient (C, meaning control) or BD condition for 4 wk and analyzed interleukin (IL)-1 production. Significantly higher ear swelling was induced in BD mice than C mice. Adaptive transfer of splenocytes from both C and BD mice induced Ni allergy in unsensitized mice. Regardless of donor mice, ear swelling was significantly higher in BD recipient mice than C recipient mice. Ni allergy was not induced in either C or BD IL-1(-/-) mice. Splenocytes from BD mice produced a significantly higher amount of IL-1beta than those from C mice. Production and mRNA expression of IL-1beta were significantly higher in BD J774.1 cells than in C cells. Biotin supplementation inhibited the augmentation of IL-1beta production in vitro. In vivo supplementation of biotin in drinking water dose-dependently decreased ear swelling in C and BD mice. These results indicate that biotin status affects Ni allergy in the elicitation phase via the upregulation of IL-1beta production in mice, suggesting that biotin supplementation may have therapeutic effects on human metal allergy.

Cloning and characterization of glycine-rich RNA-binding protein cDNAs in the moss Physcomitrella patens.

We isolated three cDNAs for the genes PpGRP1, PpGRP2 and PpGRP3 that encode glycine-rich RNA-binding proteins (GRPs) from Physcomitrella patens. Three full-length cDNA clones were isolated from a cDNA library prepared from poly(A)(+) RNA from 7-day-old protonemata of P. patens. They were named PpGRP1, PpGRP2 and PpGRP3, which encode putative polypeptides of 162, 178 and 155 residues, respectively. Preliminary genomic sequencing suggested that the positions of the three introns in the PpGRP3 gene are similar to those of introns in Arabidopsis GRP genes. PpGRP3 had a putative transit sequence. The PpGRP1-sGFP and PpGRP2-sGFP fusions were targeted to the cell nucleus, while PpGRP3-sGFP fusion was targeted to mitochondria. The level of these PpGRP transcripts as well as that of PpGRP proteins increased after cold treatment. Homoribopolymer RNA assay revealed that PpGRP3 protein show high affinity for poly(U) and poly(G). Results of phylogenetic analysis suggest that the nuclear and mitochondrial forms of GRP have been established early during the evolution of green plants.

Phase-locking of spontaneous and elicited ponto-geniculo-occipital waves is associated with acceleration of hippocampal theta waves during rapid eye movement sleep in cats.

We investigated the temporal relationship between hippocampal theta waves and ponto-geniculo-occipital waves (PGO) during rapid eye movement sleep (REM sleep) in cats. In addition, we analyzed the relationship between hippocampal theta waves and PGO as elicited by tone stimulus (PGO(E)) in order to quantitively characterize the PGO wave generator mechanism. The results showed that a spontaneous PGO tended to be phase-locked to the theta wave, which was more clearly observed in the single PGO than in the cluster. However, cluster PGO(E) tended to be phase-locked as well as single PGO(E). It was therefore suggested that the generator of PGO is activated in relation to the hippocampal theta wave. An acceleration of the theta wave associated with PGO occurrence was found, and was more markedly observed than with the cluster PGO. Although the magnitude of it was less than in the spontaneous case, an acceleration around the PGO(E) was also observed. These results suggest that the generators of theta and PGO receive some common activations, especially when a cluster PGO is generated. The interaction between PGO and hippocampal theta waves is expected to be involved in the possible functions of REM sleep.