70 research outputs found
Leaf Ecology and Radiocesium Contamination in Trees/Forests
Nonessential elements enter/accumulate in trees at certain ratios via the same uptake/translocation systems as essential elements. This phenomenon may not only damage the ecosystem but also result in human health problems. As one such nonessential element, the fate of radiocesium in trees has been extensively studied after the nuclear accident at Fukushima in 2011. Here, to better our understanding of the fate of radiocesium in nature and contribute to plan countermeasures, a review based on recent data for the Fukushima accident will be explicated with historical experiences of the global fallout, the Chernobyl accident, and many laboratory studies. In particular, the effects of specific leaf ecology (deciduous and evergreen), types of radiocesium exposure (dry/wet depositions or root uptake), and decomposition of litter on the fate of radiocesium will be precisely described with a specific uptake/translocation system of potassium, which can be recognized as the most possible entrance of radiocesium into trees
Slr0967 and Sll0939 induced by the SphR response regulator in Synechocystis sp. PCC 6803 are essential for growth under acid stress conditions
AbstractTwo-component signal transduction is the primary signaling mechanism for global regulation of the cellular response to environmental changes. We used DNA microarray analysis to identify genes that were upregulated by acid stress in the cyanobacterium Synechocystis sp. PCC 6803. Several of these genes may be response regulators that are directly involved in this type of stress response. We constructed deletion mutants for the response regulator genes and compared the growth rates of cells transfected with mutant and wild-type genes in a low pH medium. Of these mutants, deletion of sphR affected the growth rate under acid stress (pH 6.0) conditions. We examined genome-wide expression in ΔsphR mutant cells using DNA microarray to determine whether SphR was involved in the regulation of other acid stress responsive genes. Microarray and real-time quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analyses of wild-type cells showed that the expression of phoA, pstS1, and pstS2, which are upregulated under phosphate-limiting conditions, increased (2.48-, 1.88-, and 5.07-fold, respectively) after acid stress treatment for 0.5h. In contrast, pstS2 expression did not increase in the ΔsphR mutant cells after acid stress, whereas the phoA and sphX mRNA levels increased. Furthermore, qRT-PCR and northern blot analysis indicated that downregulation of the acid-responsive genes slr0967 and sll0939 occurred with the deletion of sphR. Indeed, mutants of these genes were more sensitive to acid stress than the wild-type cells. Thus, induction of Slr0967 and Sll0939 by SphR may be essential for growth under acid stress conditions. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: from Natural to Artificial
Effect of lifestyle on 6‐year periodontitis incidence or progression and tooth loss in older adults
AimTo evaluate the longitudinal association of combined healthy lifestyle factors with incidence or progression of periodontitis and tooth loss in older adults.Materials and methodsThis 6‐year study included 374 Japanese 70‐year olds with 7,157 teeth, from a source eligible baseline population of 554 individuals. Four lifestyle factors—cigarette smoking, physical activity, relative weight, and dietary quality—were scored as healthy (1 point) or unhealthy (0 point). Adding the individual scores generated the “healthy lifestyle score” (0–4 points). Multilevel mixed‐effects logistic regression models were applied to evaluate tooth‐specific associations between the baseline healthy lifestyle score and the incidence or progression of periodontitis (increase in clinical attachment loss ≥3 mm) and tooth loss.ResultsAfter 6 years, 19.0% of the teeth exhibited periodontitis incidence or progression and 8.2% were lost. Compared with a healthy lifestyle score of 0–1 (least healthy), the highest score (4 points) was associated with a significantly lower tooth‐specific risk of periodontitis (adjusted odds ratio = 0.32; 95% confidence interval: 0.16–0.62) and tooth loss (adjusted odds ratio = 0.42; 95% confidence interval: 0.23–0.77).ConclusionsSimultaneous adherence to multiple healthy lifestyle factors significantly lowers the risk of incidence or progression of periodontitis and tooth loss in older adults.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145573/1/jcpe12920_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145573/2/jcpe12920.pd
Mechanisms of tissue degeneration mediated by periostin in spinal degenerative diseases and their implications for pathology and diagnosis: a review
Periostin (POSTN) serves a dual role as both a matricellular protein and an extracellular matrix (ECM) protein and is widely expressed in various tissues and cells. As an ECM protein, POSTN binds to integrin receptors, transduces signals to cells, enabling cell activation. POSTN has been linked with various diseases, including atopic dermatitis, asthma, and the progression of multiple cancers. Recently, its association with orthopedic diseases, such as osteoporosis, osteoarthritis resulting from cartilage destruction, degenerative diseases of the intervertebral disks, and ligament degenerative diseases, has also become apparent. Furthermore, POSTN has been shown to be a valuable biomarker for understanding the pathophysiology of orthopedic diseases. In addition to serum POSTN, synovial fluid POSTN in joints has been reported to be useful as a biomarker. Risk factors for spinal degenerative diseases include aging, mechanical stress, trauma, genetic predisposition, obesity, and metabolic syndrome, but the cause of spinal degenerative diseases (SDDs) remains unclear. Studies on the pathophysiological effects of POSTN may significantly contribute toward the diagnosis and treatment of spinal degenerative diseases. Therefore, in this review, we aim to examine the mechanisms of tissue degeneration caused by mechanical and inflammatory stresses in the bones, cartilage, intervertebral disks, and ligaments, which are crucial components of the spine, with a focus on POSTN
Hyposalivation and 10‐year all‐cause mortality in an elderly Japanese population
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143602/1/ger12319.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143602/2/ger12319_am.pd
Anti-malarial activity of leaf-extract of hydrangea macrophylla, a common Japanese plant.
To find a new anti-malarial medicine derived from natural resources, we examined the leaves of 13 common Japanese plants in vitro. Among them, a leaf-extract of Hydrangea macrophylla, a common Japanese flower, inhibited the parasitic growth of Plasmodium falciparum. The IC50 of Hydrangea macrophylla leaf extract to Plasmodium falciparum was 0.18 microg/ml. The IC50 to NIH 3T3-3 cells, from a normal mouse cell line, was 7.2 microg/ml. Thus, selective toxicity was 40. For the in vivo test, we inoculated Plasmodium berghei, a rodent malaria parasite, to ddY mice and administered the leaf-extract of Hydrangea macrophylla (3.6 mg/0.2 ml) orally 3 times a day for 3 days. Malaria parasites did not appear in the blood of in the treated mice, but they did appear in the control group on day 3 or 4 after inoculation with the parasites. When leaf extract was administered to 5 mice 2 times a day for 3 days, malaria parasites did not appear in 4 of the mice but did appear in 1 mouse. In addition, the leaf-extract was administered orally 3 times a day for 3 days to Plasmodium berghei infected mice with a parasitemia of 2.7%. In the latter group, malaria parasites disappeared on day 3 after initiating the treatment, but they appeared again after day 5 or 6. Although we could not cure the mice entirely, we confirmed that the Hydrangea macrophylla leaf extract did contain an anti-malarial substance that can be administered orally.</p
radionuclides behavior in fruit plants
This paper summarizes research carried out on fruits by the Universita Cattolica del Sacro Cuore (UCSC) in Piacenza, Italy. Among the fruit crops studied, strawberry, blackberry, grapevine, apple, pear, and olive, research on strawberry and blackberry was funded by the Food Standard Agency (UK). Fruit plants were grown in pots, kept under tunnels or in open field, and contaminated with 134Cs and 85Sr via leaves or via soil. Interception in strawberry plants ranges 39–17 % for 134Cs, from anthesis (April) to predormancy (November). Leaf-to-fruit translocation occurs to a greater extent for 134Cs than for 85Sr. The distribution of contamination in fruit crops is an element-specific process: 134Cs is preferentially allocated to fruits and 85Sr to leaves. However, the activity in leaves is also species-specific: fruit species show different leaf-to-fruit translocation. Results on apple, pear, and grape crops indicate that the highest transfer from leaf to fruit occurs in apple crops. Olive plants also show 134Cs translocation from leaves to trunks. Grapevines grown on mineral soil show a root uptake higher for 85Sr than for 134Cs, while strawberries grown on a peat substrate show a root uptake higher for 134Cs than for 85Sr. Rinsing directly contaminated fruits removes 85Sr (36 %) to a greater degree than 134Cs (24 %). Transfer to olive oil is low. A 57 % of 134Cs is transferred from grapes to white wine
DOCK2 is involved in the host genetics and biology of severe COVID-19
「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target
The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force
「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection
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