Explore the vast range of titles available.

Clethra barbinervis Sieb. et Zucc. is a tree species that grows naturally at several mine sites and seems to be tolerant of high concentrations of heavy metals, such as Cu, Zn, and Pb. The purpose of this study is to clarify the mechanism(s) underlying this species' ability to tolerate the sites' severe heavy-metal pollution by considering C. barbinervis interaction with root fungal endophytes. We measured the heavy metal concentrations of root-zone soil, leaves, branches, and fine roots collected from mature C. barbinervis at Hitachi mine. We isolated fungal endophytes from surface-sterilized root segments, and we examined the growth, and heavy metal and nutrient absorption of C. barbinervis seedlings growing in sterilized mine soil with or without root fungal endophytes. Field analyses showed that C. barbinervis contained considerably high amounts of Cu, Zn, and Pb in fine roots and Zn in leaves. The fungi, Phialocephala fortinii, Rhizodermea veluwensis, and Rhizoscyphus sp. were frequently isolated as dominant fungal endophyte species. Inoculation of these root fungal endophytes to C. barbinervis seedlings growing in sterilized mine soil indicated that these fungi significantly enhanced the growth of C. barbinervis seedlings, increased K uptake in shoots and reduced the concentrations of Cu, Ni, Zn, Cd, and Pb in roots. Without root fungal endophytes, C. barbinervis could hardly grow under the heavy-metal contaminated condition, showing chlorosis, a symptom of heavy-metal toxicity. Our results indicate that the tree C. barbinervis can tolerate high heavy-metal concentrations due to the support of root fungal endophytes including P. fortinii, R. veluwensis, and Rhizoscyphus sp. via growth enhancement, K uptake promotion and decrease of heavy metal concentrations.

Anomalously fractionated sulfur isotopes in many sedimentary rocks older than 2.4 billion years have been widely believed to be the products of ultraviolet photolysis of volcanic sulfur dioxide in an anoxic atmosphere. Our laboratory experiments have revealed that reduced-sulfur species produced by reactions between powders of amino acids and sulfate at 150° to 200°C possess anomalously fractionated sulfur isotopes: Δ³³S = +0.1 to +2.1 per mil and Δ³⁶S = -1.1 to +1.1 per mil. These results suggest that reactions between organic matter in sediments and sulfate-rich hydrothermal solutions may have produced anomalous sulfur isotope signatures in some sedimentary rocks. If so, the sulfur isotope record of sedimentary rocks may be linked to the biological and thermal evolution of Earth in ways different than previously thought.

Aromatase is an estrogen synthetic enzyme that plays important roles in brain functions. To quantify aromatase expression in the brain by positron emission tomography (PET), we had previously developed [ 11 C]cetrozole, which showed high specificity and affinity. To develop more efficient PET tracer(s) for aromatase imaging, we synthesized three analogs of cetrozole. We synthesized meta-cetrozole, nitro-cetrozole, and iso-cetrozole, and prepared the corresponding 11 C-labeled tracers. The inhibitory activities of these three analogs toward aromatase were evaluated using marmoset placenta, and PET imaging of brain aromatase was performed using the 11 C-labeled tracers in monkeys. The most promising analog in the monkey study, iso-cetrozole, was evaluated in the human PET study. The highest to lowest inhibitory activity of the analogs toward aromatase in the microsomal fraction from marmoset placenta was in the following order: iso-cetrozole, nitro-cetrozole, cetrozole, and meta-cetrozole. This order showed good agreement with the order of the binding potential (BP) of each 11 C-labeled analog to aromatase in the rhesus monkey brain. A human PET study using [ 11 C]iso-analog showed a similar distribution pattern of binding as that of [ 11 C]cetrozole. The time–activity curves showed that elimination of [ 11 C]iso-cetrozole from brain tissue was faster than that of 11 C-cetrozole, indicating more rapid metabolism of [ 11 C]iso-cetrozole. [ 11 C]Cetrozole has preferable metabolic stability for brain aromatase imaging in humans, although [ 11 C]iso-cetrozole might also be useful to measure aromatase level in living human brain because of its high binding potential.

Tree-ring cellulose oxygen isotopic ratios have been widely studied as a hydrological proxy in monsoonal Asia. There has been, however, little attempt to perform proxy assessment of the intra-annual isotopic data to reconstruct hydroclimate with higher temporal resolution. We presented new intra-annual cellulose oxygen isotopic records of Japanese cedar trees spanning A.D. 1918 to 2017, and validated it as a hydrological proxy by comparing with meteorological data. There are significant negative correlations between intra-annual isotopic ratios and summer precipitation/relative humidity, as similar to annual-resolution data of earlier studies. Notably on intra-annual scales, the period showing the highest correlation gradually shifted from May to August, in corresponding to the location within the annual ring. Principal component regression analyses show the regression was more accurate over a wider duration than single regression analysis using the annual data, therefore indicating that the subdivision of the annual ring could contribute to reconstruct higher-resolution hydroclimate.

Autophagy is an important system conserved in eukaryotes that maintains homeostasis by degrading abnormal proteins. Autophagy incompetence in intestinal epithelial cells causes the abnormal function of intestinal stem cells and other cells and damages intestinal barrier function. The disruption of the intestinal barrier causes chronic inflammation throughout the body, followed by impaired glucose and lipid metabolism. Lactiplantibacillus plantarum OLL2712 (OLL2712) is a lactic acid bacterium that induces interleukin-10 production from immune cells, alleviates chronic inflammation, and improves glucose and lipid metabolism. In this study, we hypothesized that OLL2712 exerts anti-inflammatory effects by inducing autophagy and ameliorating intestinal barrier dysfunction, and we investigated its autophagy-inducing activities and functions. Caco-2 cells stimulated with OLL2712 for 24 h showed an increased number of autolysosomes per cell, compared with unstimulated cells. Therefore, the permeability of fluorescein isothiocyanate dextran 4000 (FD-4) was suppressed by inducing autophagy. In contrast, mucin secretion in HT-29-MTX-E12 cells was also increased by OLL2712 but not via autophagy induction. Finally, the signaling pathway involved in autophagy induction by OLL2712 was found to be mediated by myeloid differentiation factor 88 (MYD88). In conclusion, our findings suggest that OLL2712 induces autophagy in intestinal epithelial cells via MYD88, and that mucosal barrier function is strengthened by inducing autophagy.

Tree-ring cellulose oxygen isotopic composition (δ18O) is controlled by several hydrological factors such as precipitation, relative humidity, and temperature. A proxy system model can reveal how these factors affect tree-ring cellulose δ18O. In this study, to identify a key control on tree-ring cellulose δ18O variations, we performed model calculation of year-to year variation of tree-ring cellulose δ18O of Javanese teak in Indonesia from 1960 to 1998. Our model results reasonably reproduce the observed δ18O values and their temporal variations (r = 0.6; p < 0.001). Moreover, the sensitivity test shows that the cellulose δ18O values are sensitive to the teak growing period. The simulation result with earlier or later shifts of the growing period captured the amplitude of observed δ18O variations over 39 years. These results indicate that the tree-ring cellulose δ18O of Javanese teak might be influenced by a subtle shift of the intra-annual growing period.

The timing of the origin of photosynthesis on the early Earth is greatly debated. It is generally agreed, on the basis of the presence of biological molecules found in shales from the Hamersley Basin, Australia, that oxygenic photosynthesis had evolved 2.7 billion years (Gyr) ago. However, whether photosynthesis occurred before this time remains controversial. Here we report primary haematite crystals and associated minerals within the marine sedimentary rocks preserved in a jasper formation of the Pilbara Craton, Australia, which we interpret as evidence for the formation of these rocks in an oxygenated water body 3.46 Gyr ago. We suggest that these haematite crystals formed at temperatures greater than 60  ∘ C from locally discharged hydrothermal fluids rich in ferrous iron. The crystals precipitated when the fluids rapidly mixed with overlying oxygenated sea water, at depths greater than 200 m. As our findings imply the existence of noticeable quantities of molecular oxygen, we propose that organisms capable of oxygenic photosynthesis evolved more than 700 million years earlier than previously recognized, resulting in the oxygenation of at least some intermediate and deep ocean regions. The timing of the origin of photosynthesis remains controversial. The discovery of ancient haematite crystals that formed in a jasper formation in Australia, which was created in a marine setting, suggests that oxygen was being produced, at least locally, by photosynthesis as early as 3.46 billion years ago.

Lactic acid bacteria (LAB) have been widely used as probiotics which contribute to our health. We previously reported that subsp. 2038 and 1131, two yogurt starter strains, ameliorate the intestinal barrier dysfunction caused by tumor necrosis factor (TNF)-α and interferon (IFN)-γ in Caco-2 cells. However, Caco-2 cells differ from living organisms in various ways. We have developed a human induced pluripotent stem cell-derived crypt-villus structural small intestine (hiPSC-SI) was established with a villus-like structure containing constituent cells of the small intestine. A hiPSC-SI and LAB co-culture model was established to assess the impact of LAB on barrier function and elucidate the underlying mechanisms. The medium on the luminal side for co-culturing cells and bacteria was examined and determined to use Hanks' balanced salt solution without glucose in terms of bacterial survival rate. LAB were found to ameliorate permeability and decrease the gene expression of tight junction associated proteins induced by TNF-α and IFN-γ. Regarding cell differentiation, LAB suppressed the downregulation of , , and by cytokines. Moreover, they ameliorated reduced mucin 2 protein production and decreased the number of mucin 2-positive cells. Finally, transcriptome analysis suggested that they ameliorated the aberration in cytokine-induced cell differentiation via an anti-inflammatory effect on intestinal stem cells. The results indicate that LAB ameliorate the cytokine-induced dysfunction of intestinal barrier integrity and homeostasis disrupted by cytokines in a co-culture model of hiPSC-SI and LAB.

This paper focused on analytical validation such as the amount needed, time drift, repeatability, memory effect, analytical precision and accuracy on carbon/oxygen isotopic measurement of small carbonate samples (10–80 µg) using an IsoPrime100 mass spectrometer. 10 µg of carbonate samples yielded mass 44-intensity of 2 nA. The minimum amount needed was 10 μg and the repeatability was around 0.1 ‰ (1 s.d.). Through 24-h measurement there was no temporal variation of δ 13 C, but that of δ 18 O showed variation with decreasing the amount of CO 2 reference gas, suggesting that δ 18 O values need to conduct time drift correction. Inter-sample memory effect was not observed, indicating that IsoPrime100 mass spectrometer with CO 2 purification system is adequately evacuated after each analysis by means of pumping system. Moreover, IAEA-CO-1 and JAMSTEC-WS values calibrated by international reference NBS19 agree within error with the reference values, demonstrating the accuracy of our analytical procedure on carbon/oxygen isotopic measurement of carbonate samples. This paper offers insights into analytical validation procedure when setting up a mass spectrometer on isotopic analyses of small carbonate samples.

The technique most widely used to quantitatively measure leg edema is only a pitting edema method. It has recently become possible to digitize B-mode ultrasound images and accurately quantify their brightness using an image-analysis software program. The purpose of this study was to find new indices of the grade of leg skin, to study whether or not analyses of the subcutaneous layer of leg skin on ultrasound images using image-editing software program can be used to evaluate it and to digitize it. Images of 282 subcutaneous layers of leg skin in 141 pregnant women were obtained using a B-scan portable ultrasound device. Rectangular photographs (vertical: skin thickness; horizontal: width of probe) were obtained using an image-editing program, and the luminous intensity (pixel grayscale: 0–255) and thickness of the skin were calculated using a histogram. We investigated the correlation between these parameters and the grade of pitting edema (0–3). There was a significant positive correlation between the grade of pitting edema and the average luminous intensity value, its standard deviation, and the skin thickness (ρ = 0.36, ρ = 0.22, ρ = 0.51, p < 0.0001, respectively). In particular, there was strong positive correlation between the grade of pitting edema and both the total number of pixels in a rectangle × (multiplied by) the average luminous intensity value and the total number of pixels in a rectangle × the standard deviation of the average luminous intensity value (ρ = 0.58 and ρ = 0.59, p < 0.0001, respectively). We could quantitatively evaluate the grade of leg edema by analyzing ultrasound photographs of the subcutaneous layer of the leg skin using an image-editing software program and found new indices to digitize it.