•Biochar reduced runoff volumes and ratios of slopping land.•Biochar decreased the concentrations of N and P in the runoff.•Biochar has induced significant reduction of the nutrients losses.•Biochar ...exhibits a risk of increasing sediment loss under tillage conditions.
The effects of biochar on runoff and loss of soil and nutrients in the subtropical regions of China are rarely documented. Two field experiments, an orchard and a cropland field were set up, involving two treatments: biochar (BC) and no-biochar (NBC). The effects of BC on runoff volumes and ratios, sediment yield and the level of nutrient losses were monitored and evaluated over three years (2014–2016). Results showed that the treatment of BC induced a significant reduction in the runoff and nutrients losses. By plotting the data collected for the BC application, we observed that the average annual runoff decreased by 19–28%, whereas the average annual sediment yield by 11%. The cumulative values of total nitrogen (N) and phosphorus (P) losses were also substantially minimized by the BC treatment compared with the NBC one (P<0.05). However, the average annual concentrations of total N and P losses as obtained from the BC plots (16.21mgL−1 and 0.72–0.99mgL−1) were still high, and exceeding the wastewater discharge standard (N: 15mgL−1 and P: 0.5mgL−1). In addition, under tillage conditions, the BC application led to larger sediments yield (6.5gm−2) in contrast with the NBC treatment (5.5gm−2). In general, these findings can suggest that BC exhibits a vital efficiency in the control of soil erosion process, but there is a risk of increasing sediment loss under tillage conditions, which might need to be made up by combined with biological and agronomic managements such as straw mulching or adding polyacrylamide into soil in order to control further soil erosion.
Summary
Villosiclava virens (Vv) is an ascomycete fungal pathogen that causes false smut disease in rice. Recent reports have revealed some interesting aspects of the enigmatic pathogen to address ...the question of why it specifically infects rice flowers and converts a grain into a false smut ball. Comparative and functional genomics have suggested specific adaptation of Vv in the colonization of rice flowers. Anatomical studies have disclosed that Vv specifically infects rice stamen filaments before heading and intercepts seed formation. In addition, Vv can occupy the whole inner space of a spikelet embracing all floral organs and activate the rice grain‐filling network, presumably for nutrient acquisition to support the development of the false smut ball. This profile provides a general overview of the rice false smut pathogen, and summarizes advances in the Vv life cycle, genomics and genetics, and the molecular Vv–rice interaction. Current understandings of the Vv–rice pathosystem indicate that it is a unique and interesting system which can enrich the study of plant–pathogen interactions.
Taxonomy: Ustilaginoidea virens is the anamorph form of the pathogen (Kingdom Fungi; Phylum Ascomycota; Class Ascomycetes; Subclass Incertae sedis; Order Incertae sedis; Family Incertae sedis; Genus Ustilaginoidea). The teleomorph form is Villosiclava virens (Kingdom Fungi; Phylum Ascomycota; Class Ascomycetes; Subclass Sordariomycetes; Order Hypocreales; Family Clavicipitaceae; Genus Villosiclava).
Disease symptoms: The only visible symptom is the replacement of rice grains by ball‐shaped fungal mycelia, namely false smut balls. When maturing, the false smut ball is covered with powdery chlamydospores, and the colour changes to yellowish, yellowish orange, green, olive green and, finally, to greenish black. Sclerotia are often formed on the false smut balls in autumn.
Identification and detection: Vv conidia are round to elliptical, measuring 3–5 μm in diameter. Chlamydospores are ornamented with prominent irregularly curved spines, which are 200–500 nm in length. The sclerotia are black, horseshoe‐shaped and irregular oblong or flat, ranging from 2 to 20 mm. Nested polymerase chain reaction (PCR) and quantitative PCR have been developed to specifically detect Vv presence in rice tissues and other biotic and abiotic samples in fields.
Host range: Rice is the primary host for Vv. Natural infection by Vv has been found on several paddy field weeds, including Digitaria marginata, Panicum trypheron, Echinochloa crusgalli and Imperata cylindrica. However, the occurrence of infection in these potential alternative hosts is very rare.
Life cycle: Vv infects rice spikelets at the late rice booting stage, and produces false smut balls covered with dark‐green chlamydospores. Occasionally, sclerotia form on the surface of false smut balls in late autumn when the temperature fluctuates greatly between day and night. Both chlamydospores and sclerotia may serve as primary infection sources. Rainfall at the rice booting stage is a major environmental factor resulting in epidemics of rice false smut disease.
Disease control: The use of fungicides is the major approach for the control of Vv. Several fungicides, such as cuproxat SC, copper oxychloride, tebuconazole, propiconazole, difenoconazole and validamycin, are often applied. However, the employment of resistant rice cultivars and genes has been limited, because of the poor understanding of rice resistance to Vv.
Useful websites: Villosiclava virens genome sequence: http://www.ncbi.nlm.nih.gov/Traces/wgs/?val=JHTR01#contigs
Defects in silicon carbide have been explored as promising spin systems in quantum technologies. However, for practical quantum metrology and quantum communication, it is critical to achieve ...on-demand single spin-defect generation. In this work, we present the generation and characterization of shallow silicon vacancies in silicon carbide by using different implanted ions and annealing conditions. The conversion efficiency of a silicon vacancy of helium ions is shown to be higher than that by carbon and hydrogen ions in a wide implanted fluence range. Furthermore, after optimizing the annealing conditions, the conversion efficiency can be increased more than 2 times. Due to the high density of the generated ensemble defects, the sensitivity of sensing a static magnetic field can be reached as high as η B ≈ 23.5 μ T / H z , which is about 9 times smaller than previous results. By carefully optimizing implanted conditions, we further show that a single silicon vacancy array can be generated with a high conversion efficiency of about 80%. The results pave the way for using an on-demand-generated single silicon vacancy for quantum information processing and quantum photonics.
MYC transcriptional factors are members of the bHLH (basic helix-loop-helix) superfamily, and play important roles in plant growth and development. Recent studies have revealed that some MYCs are ...involved in the crosstalk between Jasmonic acid regulatory pathway and light signaling in Arabidopsis, but such kinds of studies are rare in wheat, especially in photo-thermo-sensitive genic male sterile (PTGMS) wheat line.
27 non-redundant MYC gene copies, which belonged to 11 TaMYC genes, were identified in the whole genome of wheat (Chinese Spring). These gene copies were distributed on 13 different chromosomes, respectively. Based on the results of phylogenetic analysis, 27 TaMYC gene copies were clustered into group I, group III, and group IV. The identified TaMYC genes copies contained different numbers of light, stress, and hormone-responsive regulatory elements in their 1500 base pair promoter regions. Besides, we found that TaMYC3 was expressed highly in stem, TaMYC5 and TaMYC9 were expressed specially in glume, and the rest of TaMYC genes were expressed in all tissues (root, stem, leaf, pistil, stamen, and glume) of the PTGMS line BS366. Moreover, we found that TaMYC3, TaMYC7, TaMYC9, and TaMYC10 were highly sensitive to methyl jasmonate (MeJA), and other TaMYC genes responded at different levels. Furthermore, we confirmed the expression profiles of TaMYC family members under different light quality and plant hormone stimuli, and abiotic stresses. Finally, we predicted the wheat microRNAs that could interact with TaMYC family members, and built up a network to show their integrative relationships.
This study analyzed the size and composition of the MYC gene family in wheat, and investigated stress-responsive and light quality induced expression profiles of each TaMYC gene in the PTGMS wheat line BS366. In conclusion, we obtained lots of important information of TaMYC family, and the results of this study was supposed to contribute novel insights and gene and microRNA resources for wheat breeding, especially for the improvement of PTGMS wheat lines.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Mutations in gene regulatory elements have been associated with a wide range of complex neuropsychiatric disorders. However, due to their cell-type specificity and difficulties in characterizing ...their regulatory targets, the ability to identify causal genetic variants has remained limited. To address these constraints, we perform an integrative analysis of chromatin interactions, open chromatin regions and transcriptomes using promoter capture Hi-C, assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) and RNA sequencing, respectively, in four functionally distinct neural cell types: induced pluripotent stem cell (iPSC)-induced excitatory neurons and lower motor neurons, iPSC-derived hippocampal dentate gyrus-like neurons and primary astrocytes. We identify hundreds of thousands of long-range cis-interactions between promoters and distal promoter-interacting regions, enabling us to link regulatory elements to their target genes and reveal putative processes that are dysregulated in disease. Finally, we validate several promoter-interacting regions by using clustered regularly interspaced short palindromic repeats (CRISPR) techniques in human excitatory neurons, demonstrating that CDK5RAP3, STRAP and DRD2 are transcriptionally regulated by physically linked enhancers.
Dysregulated neurodevelopment with altered structural and functional connectivity is believed to underlie many neuropsychiatric disorders, and 'a disease of synapses' is the major hypothesis for the ...biological basis of schizophrenia. Although this hypothesis has gained indirect support from human post-mortem brain analyses and genetic studies, little is known about the pathophysiology of synapses in patient neurons and how susceptibility genes for mental disorders could lead to synaptic deficits in humans. Genetics of most psychiatric disorders are extremely complex due to multiple susceptibility variants with low penetrance and variable phenotypes. Rare, multiply affected, large families in which a single genetic locus is probably responsible for conferring susceptibility have proven invaluable for the study of complex disorders. Here we generated induced pluripotent stem (iPS) cells from four members of a family in which a frameshift mutation of disrupted in schizophrenia 1 (DISC1) co-segregated with major psychiatric disorders and we further produced different isogenic iPS cell lines via gene editing. We showed that mutant DISC1 causes synaptic vesicle release deficits in iPS-cell-derived forebrain neurons. Mutant DISC1 depletes wild-type DISC1 protein and, furthermore, dysregulates expression of many genes related to synapses and psychiatric disorders in human forebrain neurons. Our study reveals that a psychiatric disorder relevant mutation causes synapse deficits and transcriptional dysregulation in human neurons and our findings provide new insight into the molecular and synaptic etiopathology of psychiatric disorders.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In response to the current global health emergency posed by the Zika virus (ZIKV) outbreak and its link to microcephaly and other neurological conditions, we performed a drug repurposing screen of ...∼6,000 compounds that included approved drugs, clinical trial drug candidates and pharmacologically active compounds; we identified compounds that either inhibit ZIKV infection or suppress infection-induced caspase-3 activity in different neural cells. A pan-caspase inhibitor, emricasan, inhibited ZIKV-induced increases in caspase-3 activity and protected human cortical neural progenitors in both monolayer and three-dimensional organoid cultures. Ten structurally unrelated inhibitors of cyclin-dependent kinases inhibited ZIKV replication. Niclosamide, a category B anthelmintic drug approved by the US Food and Drug Administration, also inhibited ZIKV replication. Finally, combination treatments using one compound from each category (neuroprotective and antiviral) further increased protection of human neural progenitors and astrocytes from ZIKV-induced cell death. Our results demonstrate the efficacy of this screening strategy and identify lead compounds for anti-ZIKV drug development.
Purpose
Biomechanical comparison between rigid and non-rigid posterior stabilization systems following lumbar interbody fusion has been conducted in several studies. However, most of these previous ...studies mainly focused on investigating biomechanics of adjacent spinal segments or spine stability. The objective of the present study was to compare biomechanical responses of the fusion devices when using different posterior instrumentations.
Methods
Finite-element model of the intact human lumbar spine (L1–sacrum) was modified to simulate implantation of the fusion cage at L4–L5 level supplemented with different posterior stabilization systems including (i) pedicle screw-based fixation using rigid connecting rods (titanium rods), (ii) pedicle screw-based fixation using flexible connecting rods (PEEK rods) and (iii) dynamic interspinous spacer (DIAM). Stress responses were compared among these various models under bending moments.
Results
The highest and lowest stresses in endplate, fusion cage and bone graft were found at the fused L4–L5 level with DIAM and titanium rod stabilization systems, respectively. When using PEEK rod for the pedicle screw fixation, peak stress in the pedicle screw was lower but the ratio of peak stress in the rods to yield stress of the rod material was higher than using titanium rod.
Conclusions
Compared with conventional rigid posterior stabilization system, the use of non-rigid stabilization system (i.e., the PEEK rod system and DIAM system) following lumbar interbody fusion might increase the risks of cage subsidence and cage damage, but promote bony fusion due to higher stress in the bone graft. For the pedicle screw-based rod stabilization system, using PEEK rod might reduce the risk of screw breakage but increased breakage risk of the rod itself.
The deregulation of microRNAs (miRNAs) plays an important role in human hepatocarcinogenesis. In this study, we highlight exosomes as mediators involved in modulating miRNA profiles in hepatocellular ...carcinoma (HCC) cells. First, we examined the different miRNA expression profiles in HCC cells and HCC cell–derived exosomes. Next, coculture experiments indicated that HCC cell–derived exosomes promoted the cell growth, migration, and invasion of HCC cells and had the ability to shuttle miRNAs to recipient cells. Further, our data showed that Vps4A, a key regulator of exosome biogenesis, was frequently down‐regulated in HCC tissues. The reduction of Vps4A in HCC tissues was associated with tumor progression and metastasis. In vitro studies revealed that Vps4A repressed the growth, colony formation, migration, and invasion of HCC cells. We further investigated the role and involvement of Vps4A in suppressing the bioactivity of exosomes and characterized its ability to weaken the cell response to exosomes. By small RNA sequencing, we demonstrated that Vps4A facilitated the secretion of oncogenic miRNAs in exosomes as well as accumulation and uptake of tumor suppressor miRNAs in cells. A subset of Vps4A‐associated miRNAs was identified. Kyoto Encyclopedia of Genes and Genomes pathway analysis indicated that the phosphatidylinositol‐3‐kinase/Akt signaling pathway was the most likely candidate pathway for modulation by these miRNAs. Indeed, we proved that the phosphatidylinositol‐3‐kinase/Akt pathway was inactivated by Vps4A overexpression. Conclusion: Exosome‐mediated miRNA transfer is an important mechanism of self‐modulation of the miRNA expression profiles in HCC cells, and Vps4A may function as a tumor suppressor, which utilizes exosomes as mediators to regulate the secretion and uptake of miRNAs in hepatoma cells; these observations provide new insights into the development of HCC. (Hepatology 2015;61:1284–1294)
DNA methylation has been traditionally viewed as a highly stable epigenetic mark in postmitotic cells. However, postnatal brains appear to show stimulus-induced methylation changes, at least in a few ...identified CpG dinucleotides. How extensively the neuronal DNA methylome is regulated by neuronal activity is unknown. Using a next-generation sequencing-based method for genome-wide analysis at single-nucleotide resolution, we quantitatively compared the CpG methylation landscape of adult mouse dentate granule neurons in vivo before and after synchronous neuronal activation. About 1.4% of 219,991 CpGs measured showed rapid active demethylation or de novo methylation. Some modifications remained stable for at least 24 h. These activity-modified CpGs showed a broad genomic distribution with significant enrichment in low-CpG density regions, and were associated with brain-specific genes related to neuronal plasticity. Our study implicates modification of the neuronal DNA methylome as a previously underappreciated mechanism for activity-dependent epigenetic regulation in the adult nervous system.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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