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Uncoordinated carbon-nitrogen ratio in raw materials will lead to excessive contents of higher alcohols in alcoholic beverages. The effect of GAT1 gene, the GATA transcription activator, on higher alcohol biosynthesis was investigated to clarify the mechanism of Saccharomyces cerevisiae regulating higher alcohol metabolism under high concentrations of free amino nitrogen (FAN). The availability of FAN by strain SDT1K with a GAT1 double-copy deletion was 28.31% lower than that of parent strain S17, and the yield of higher alcohols was 33.91% lower. The transcript levels of the downstream target genes of GAT1 and higher alcohol production in the double-copy deletion mutant suggested that a part of the effect of GAT1 deletion on higher alcohol production was the downregulation of GAP1, ARO9, and ARO10. This study shows that GATA factors can effectively regulate the metabolism of higher alcohols in S. cerevisiae and provides valuable insights into higher alcohol biosynthesis, showing great significance for the wheat beer industry. [ABSTRACT FROM AUTHOR]

The quantum anomalous Hall (QAH) phase is a topological state of matter characterized by a nonzero quantized Hall conductivity without an external magnetic field. The realizations of the QAH effect, however, are experimentally challengeable. Based on ab initio calculations, here, we propose an intrinsic QAH phase in the Mn-dicyanoanthracene (DCA) Kagome lattice. The nontrivial topology in Kagome bands is confirmed by the nonzero Chern number, quantized Hall conductivity, and gapless chiral edge states of the Mn-DCA lattice. A tight-binding model is further constructed to clarify the origin of the QAH effect. Furthermore, its Curie temperature, estimated to be ~253K using the Monte-Carlo simulation, is comparable with room temperature and higher than that of most of the two-dimensional ferromagnetic thin films. Our findings present a reliable material platform for the observation of the QAH effect in covalent-organic frameworks. [ABSTRACT FROM AUTHOR]

Searching for two-dimensional (2D) realistic materials that are able to realize room-temperature quantum spin Hall effects is currently a growing field. Here, through ab initio calculations, we identify arsenene oxide, AsO, as an excellent candidate, which demonstrates high stability, flexibility, and tunable spin-orbit coupling gaps. In contrast to known pristine or functionalized arsenene, the maximum nontrivial bandgap of AsO reaches 89meV and can be further enhanced to 130meV under biaxial strain. By sandwiching 2D AsO between boron nitride sheets, we propose a quantum well in which the band topology of AsO is preserved with a sizeable bandgap. Considering that AsO having fully oxidized surfaces are naturally stable against surface oxidization and degradation, this functionality provides a viable strategy for designing topological quantum devices operating at room temperature. [ABSTRACT FROM AUTHOR]

With continuous hydrocarbon exploration extending to deeper basins, the deepest industrial oil accumulationwas discovered below 8,200 m, revealing a new exploration field. Hence, the extent to which oil exploration can be extended, and the prediction of the depth limit of oil accumulation (DLOA), are issues that have attracted significant attention in petroleum geology. Since it is difficult to characterize the evolution of the physical properties of the marine carbonate reservoir with burial depth, and the deepest drilling still cannot reach the DLOA. Hence, the DLOA cannot be predicted by directly establishing the relationship between the ratio of drilling to the dry layer and the depth. In this study, by establishing the relationships between the porosity and the depth and dry layer ratio of the carbonate reservoir, the relationships between the depth and dry layer ratio were obtained collectively. The depth corresponding to a dry layer ratio of 100% is the DLOA. Based on this, a quantitative prediction model for the DLOA was finally built. The results indicate that the porosity of the carbonate reservoir, Lower Ordovician in Tazhong area of Tarim Basin, tends to decrease with burial depth, and manifests as an overall low porosity reservoir in deep layer. The critical porosity of the DLOA was 1.8%, which is the critical geological condition corresponding to a 100% dry layer ratio encountered in the reservoir. The depth of the DLOA was 9,000 m. This study provides a new method for DLOA prediction that is beneficial for a deeper understanding of oil accumulation, and is of great importance for scientific guidance on deep oil drilling. [ABSTRACT FROM AUTHOR]

Two-dimensional dumbbell (DB) stanene has been proposed as a promising candidate material for realizing quantum spin Hall effect (QSHE) by Tang et al. [Phys. Rev. B 90, 121408 (2014)]. However, the small bulk-gap limits its possible applications at room temperature. Based on first-principles calculations, we predict that its band gap can be enhanced to 148 meV under methyl-functionalization, which can be further tuned by applying lattice strain. The QSHE is confirmed by s-px,y band inversion, topological invariant Z2=1, and helical gapless edge within bulk band gap. Notably, the characteristic properties of edge states, such as the large Fermi velocity and Dirac cone, can be modulated by edge modification. The effects of substrates on topological properties are explored when it is grown on various substrates, like SiC, h-BN, and Bi2Te3 sheets. These findings provide significant guidance for future fabrication and realistic applications of QSHE based on stanene in spintronics. [ABSTRACT FROM AUTHOR]

A soft engineering method of removing existed flood defences to restore salt marsh has been widely used to protect the coastal region in European countries. This study investigates the response of the intertidal zone at Freiston Shore to a controlled embankment retreat (CER) completed in August 2002, and interprets changes in sediment dynamics and bed level across the intertidal zone based on an analysis of temporal and spatial variations in the suspended sediment flux over semi-diurnal tidal cycles. In addition, a numerical simulation (Delft3D) was performed to analyze the long-term development of the intertidal zone. The current velocity turned further seaward during the ebb 25 months after the de-embankment, with an apparent simultaneous decline of suspended sediment concentration (SSC). Between April 2003 and October 2004, the middle intertidal flat shifted from an erosional to an accretionary state, whereas the reverse was true on the lower intertidal flat. The spatial pattern of suspended sediment flux suggests that sediments eroded from the mid-intertidal zone after 9 months of CER have been re-deposited in the lower intertidal zone, and the process was reversed 16 months after. Tidally residual suspended sediment flux varied with the changing sediment dynamics. The modeling results indicate a similar trend in bed level change to the field observations at Freiston Shore, which was in an early phase of intertidal flat readjustment to the CER. Tidal creek system played an important role in transient geomorphological shift between the middle and lower intertidal flat. Furthermore, the model simulation revealed the time variation of bed level changes at different elevations over the intertidal flat, indicating that the flat would essentially revert to its original pre-CER morphology within decades, which depended highly upon the sediment supply condition. Finally, a conceptual model is developed, based on field survey and numerical simulations, to summarize the developmental processes operating within the intertidal zone in response to CER. [ABSTRACT FROM AUTHOR]

Housing provision in Chinese cities has changed from a socialist welfare system to a marketised system in a short period of 20 years. Where and how do the urban poor live under this marketised system? What policies have the government developed to help the poor? How effective are these policies? This article contributes to the literature on recent housing changes in China and provides some answers to these questions. Discussion and analysis is based on the study of recent government reports, policy documents and fieldwork set in Beijing and four other cities. While many countries have reduced their social housing provision either under the influence of neo-liberal ideologies, or the pressure to cut expensive social expenditure during the global financial crisis, China has substantially reconstructed its social housing provision system to provide assistance to the urban poor. Over the last five years, housing support has been given to many poor families through either direct housing allocation or through means tested housing benefits. The wider impact of this system however has been affected by the exclusion of millions of poor rural migrants working in cities. [ABSTRACT FROM PUBLISHER]

The sedimentary environment of a large coastal embayment, Jiaozhou Bay, eastern China, in terms of erosion/siltation, has been assessed on the basis of seabed bathymetry and coastline data sets from sea charts ( 1936-2002) and Landsat-5 TM images (1986-2011). Nine types of sedimentary environment are identified according to the sedimentation rate. The results indicate that slow siltation was generally present from 1936 to 1963, with exceptions of some patchy, slightly eroding areas within the embayment. Transformation to a slow erosion pattern occurred in the main channels over the central embayment in 1963, and such a situation continued until 1982. Subsequently, since 1986, most of the coastlines extended toward the sea at a rate of 101-102 m y-1; this was mainly attributable to human activities, including reclamation over the NW tidal-flat and harbour construction along the east and south coastlines. Using the same data set, patterns of changes in tidal prism and deposition rate within the entrance channel were established. An equivalent friction coefficient (K) is proposed to evaluate the P-A relationship of the large tidal inlets in Jiaozhou Bay. The K value increases gradually over time, indicating a trend toward stable equilibrium in Jiaozhou Bay. This coefficient can be used to examine the status of morphological stability and equilibrium of coastal embayments. [ABSTRACT FROM AUTHOR]

Presents information on a study that provided genetic evidence that sonic hedgehog from retinal ganglion cells promotes the development of optic disc and stalk neuroepithelial cells. Methodology of the study; Results and discussion on the study.

The article argues that the extent to which the Chinese housing system has been transformed is more limited than analysis of Eastern Europe suggests. There are also specific aspects of the Chinese system that affect the pattern of benefit. These particularly involve rural or urban divisions, the role of work units and the particular class structure developed in China. Chinese government policies were aimed at the whole society, their impact on different social and economic groups vary. Although housing reform in China has been referred to as the largest privatization programme, it is restricted to urban areas. It has very limited impacts on rural society apart from encroaching on large quantities of good agricultural land. It is also almost irrelevant to the large numbers of rural migrants found in the cities. Throughout the reform, urban and rural registration was maintained with some relaxation in the control of temporary population movement. Government statistics show that urban housing conditions improved dramatically after 1978, but this relates only to officially registered urban residents. Rural to urban migrants could only find housing in the flourishing private-rental sector and it was not unusual to find several rural migrants crowded into one small rented room in the suburban areas of urge cities.

The transition between a tide-dominated estuary and a tide-dominated delta, which is observed in modern settings and repeatedly throughout the geologic record, is a critical process for understanding sea-level and environmental changes. This transition remains poorly documented, however, leaving a knowledge gap about the sedimentary and stratigraphic processes involved. To help bridge the gap, we reexamined the postglacial transgressive system beneath the modern Changjiang (Yangtze River) Delta, built by one of the world's largest rivers, using new chirp data supplemented by correlation with previously documented boreholes. Our results revealed a previously undocumented tide-dominated estuary-to-delta transition around the Younger Dryas, with the pretransition evolution dominated by the retrogradation of the tide-dominated estuary, which fills most of the accommodation space in the lowstand incised valley. This transition occurred when the middle and seaward parts of the estuary reached the subaqueous modern Changjiang Delta area and underwent extensive tidal erosion. Overlying the tidal ravinement, a series of ridge-and-swale structures formed due to tidal/fluviotidal channelization on the mud-dominated heterolithic substrate, primarily consisting of delta-front sediments characterized by flat, stratified reflections (bedding) with shallowing-upward trends. Ridge orientation rotates clockwise from north to south, with intervening swales bifurcating from a common apex point, and these features are flanked by inclined and sigmoidal levee-like channel fills dominated by homogeneous mud (acoustically transparent material). We reinterpret these features as tide-dominated delta islands and distributary channels, rather than the previously interpreted erosional mud ridges in the seaward part of the estuary, as they align with patterns observed in classic tide-dominated deltas. These patterns also suggest a shift from delta-front to delta-plain environments coinciding with shoreline advance ca. 10 k.y. B.P., but this was preceded by the evolution of a backstepping delta. Our study highlights the interplay between sediment supply and sea-level fluctuations in controlling the large-scale stratigraphic and environmental evolution of tidal-dominated river mouth systems. In the transgressive, paleo-Changjiang mouth, this interplay drove the system to evolve through stages of retrogradational estuary, backstepping delta, and progradational delta, and each environment differs significantly from the pattern observed in the modern Changjiang Delta. This study provides important insights for evaluating the evolution and sequence-stratigraphic reconstruction of other tidal depositional systems. [ABSTRACT FROM AUTHOR]

In this paper, the negative ion behavior in a C4F8 inductively coupled plasma (ICP) is investigated using a hybrid model. The model predicts a non-monotonic variation of the total negative ion density with power at low pressure (10-30 mTorr), and this trend agrees well with experiments that were carried out in many fluorocarbon (fc) ICP sources, like C2F6, CHF3, and C4F8. This behavior is explained by the availability of feedstock C4F8 gas as a source of the negative ions, as well as by the presence of low energy electrons due to vibrational excitation at low power. The maximum of the negative ion density shifts to low power values upon decreasing pressure, because of the more pronounced depletion of C4F8 molecules, and at high pressure (~50 mTorr), the anion density continuously increases with power, which is similar to fc CCP sources. Furthermore, the negative ion composition is identified in this paper. Our work demonstrates that for a clear understanding of the negative ion behavior in radio frequency C4F8 plasma sources, one needs to take into account many factors, like the attachment characteristics, the anion composition, the spatial profiles, and the reactor configuration. Finally, a detailed comparison of our simulation results with experiments is conducted. [ABSTRACT FROM AUTHOR]

China has experienced high rate urbanization in recent years, with urban population increased from 460 to 750 million and the built-up area of metropolis expanded by almost 60% since 2000. Urban landscape has been dramatically changed by intensified inner-city development and urban sprawl. In recent years, the changes in urban form has transformed from expansion to restructuring. A good understanding of urban expansion and spatial restructuring as a consequence of urbanization has important policy implications, enhancing the knowledge of spatial variations in urban growth in transitional Chinese cities and assisting with sustainable urban and regional planning. Using the Landsat satellite images from 1995 to 2015, this research explores urban expansion and its spatial patterns in second-tier Chinese cities, taking Tianjin, Hangzhou and Chengdu as examples, which are the leaders in the urbanization in Northern, Eastern and Western China, respectively. The study area includes the city proper in the three case study cities. Figure 1 shows the expansion of urban area in the three cities over the study time period. By visual inspection, it can be observed that the spatial pattern of urban land use growth varies across the three cities. For example, Tianjin has been largely expanding towards the east, particularly the Tianjin Binhai New Area, which has been rapidly developed into a new city core. The city of Chengdu seems having been expanding toward all directions of the surrounding area, integrated with the adjacent towns into a larger urban agglomeration. Further work will focus on quantitative analysis of the spatial patterns of urban expansion using geographical information system (GIS)-based spatial analytics, as well as the association between urban expansion and socioeconomic changes, with a reflection on the role of national/local policies. [ABSTRACT FROM AUTHOR]

Objective: To study how the CD200‐CD200R1 signaling pathway modulates poststroke inflammation and advances our knowledge of immune responses to ischemia insults in stroke. Methods: Focal middle cerebral artery occlusion (MCAO) was induced in mice for 90 min, and mice were sacrificed at 1, 3, and 7 days of reperfusion. CD200, CD200R1, iNOS, and Arg‐1 expression in ischemic brains was assessed by Western blotting (WB), and immunohistochemical (IHC) staining was performed to examine the expression of CD200 on neurons and CD200R1 on infiltrating lymphocytes. The severity of neurobehavioral deficits was evaluated by neurological deficit scores (NDS) and infarction volume estimated by TTC staining. To study the relationship between CD200/CD200R1 expression and the diversity of the neuroinflammatory response in stroke, CD200Fc (CD200R1 agonist) was subcutaneously injected at onset, at 1 day and 2 days after MCAO operation, and the brains were collected for detection at 3 days after MCAO/R (reperfusion). Results: CD200 expression on neurons increased at 1 day and then decreased at 3 days after MCAO/R, and the expression of CD200R1 on lymphocytes showed an opposite temporal pattern as tested by IHC. The WB results showed that CD200/CD200R1 variance exhibited a similar pattern of IHC results, and the level of iNOS peaked at 1 day and then decreased gradually, but Arg‐1 increased with time after MCAO/R in ischemic brains. After CD200Fc injection, CD200R1 expression significantly increased, and CD200Fc promoted Arg‐1 but inhibited iNOS expression. The infarct volume and NDS of the group treated with CD200Fc were significantly smaller than those of the IgG2a‐treated group. Conclusions: The CD200‐CD200R1 signaling pathway regulates neuroinflammation after stroke. Stimulation of CD200R1 by CD200Fc promotes the anti‐inflammatory response and alleviates ischemic injury. [ABSTRACT FROM AUTHOR]

The search for a new quantum spin Hall (QSH) phase and effective manipulation of its edge states are very important for both fundamental sciences and practical applications. Here, we use first-principles calculations to study the strain-driven topological phase transition of two-dimensional (2D) arsenene monolayer. We find that the band gap of arsenene decreases with increasing strain and changes from indirect to direct, and then the s-p band inversion takes place at the Г point as the tensile strain is larger than 11.14%, which leads to a nontrivially topological state. A single pair of topologically protected helical edge states is established for the edge of arsenene, and their QSH states are confirmed with the nontrivial topological invariant Z2  =  1. We also propose high-dielectric BN as an ideal substrate for the experimental synthesis of arsenene, maintaining its nontrivial topology. These findings provide a promising candidate platform for topological phenomena and new quantum devices operating at nanoelectronics. [ABSTRACT FROM AUTHOR]

Using observations and theoretical models, a substantial topographic modulation on the quasigeostrophic (QG) dynamics, which results in a primary surface mode distinct from the classic first baroclinic (BC1) mode with a flat bottom, is revealed in the northern South China Sea (NSCS). In contrast to open oceans, the surface-intensified modes decay downward more rapidly over the continental slope of the NSCS, with a mean e-folding scale of approximately 1/5 of water depth. The subinertial flow variability appears to be vertically incoherent, with planetary and topographic Rossby waves dominating in the upper and deep layers, respectively. With a larger deformation radius (Rd), the surface-mode Rossby waves propagate at a phase speed ~1.5 times of that of the BC1 mode. Moreover, the modal structures can be substantially modified by seasonal NSCS circulation, which is significantly enhanced over continental slopes. Analysis of the triad interactions further implies that the short waves tend to transfer energy to larger scales via the inverse cascade and only those with wavelengths larger than Rd ≈ 70 km in the NSCS can persist because of a slower unstable growth rate but a higher fraction of upscale energy transfer. The present theory excludes the bottom-trapped mode, which is closely associated with topographic Rossby waves and is observed to be significant in the abyssal NSCS. Hence, a complete normalmode basis for any QG state is required for a study that focuses on flow variability throughout the water column. Our findings provide an insight into the vertical partition of horizontal kinetic energy for QG motions, as well as the relevant oceanic variation in marginal seas. [ABSTRACT FROM AUTHOR]

How climate controls tropical cyclone variability has critical implications for modern human society but is not well understood due to the short length of observational records. To probe this knowledge gap, we present a synthesis of intense typhoon activity from the northwestern Pacific over the past 2000 years, which is supported by a new, wellresolved tidal flat sedimentary record from the Jiangsu coast, eastern China. The record reveals nine intervals of typhoon frequency, indicating that the frequency of intense typhoons has varied on multi-centennial scales over the past 2000 years. Our synthesis shows strong evidence for a seesaw pattern of intense typhoon frequency between southeastern China and Japan and Korea. This pattern can be explained by the El Niño and Southern Oscillation-East Asian Monsoon- sea surface temperature hypothesis, which potentially explains the basin-wide typhoon climate in the northwestern Pacific region. A shift in typhoon activity was identified from 550-280 to 280-50 yr B.P. during the Little Ice Age, when typhoon activity changed from active to quiescent or vice versa. Centennialscale shifts in Intertropical Convergence Zone and Western Pacific Warm Pool sea surface temperature are likely to be the primary forcing mechanisms driving this shift. Results obtained here provide links between typhoon activity and the El Niño and Southern Oscillation, the East Asian Monsoon, and the Western Pacific Warm Pool sea surface temperature, and therefore improve our ability to fully assess intense typhoon activity in future climate warming. [ABSTRACT FROM AUTHOR]

This study aimed to determine whether and how the glucagon-like peptide 1 receptor (GLP-1R) agonist liraglutide affects the chemoresistance and chemosensitivity of pancreatic cancer cells to gemcitabine in vitro and in vivo. The GLP-1R and protein kinase A (PKA) levels were compared between the human pancreatic cancer cell line PANC-1 and the gemcitabine-resistant cell line PANC-GR. The in vitro effects of liraglutide on the cell proliferation and apoptosis as well as the nuclear factor-kappa B NF-κB expression levels of PANC-GR cells were evaluated. In addition, a mouse xenograft model of human pancreatic cancer was established by s.c. injection of PANC-1 cells, and the effects of liraglutide on the chemosensitivity were evaluated in vitro and in vivo. In contrast to PANC-1 cells, PANC-GR cells exhibited lower expression levels of GLP-1R and PKA. Incubation with liraglutide dose dependently inhibited the growth, promoted the apoptosis, and increased the expression of GLP-1R and PKA of PANC-GR cells. Similar effects of liraglutide were observed in another human pancreatic cancer cell line MiaPaCa-2/MiaPaCa-2-GR. Either the GLP-1R antagonist Ex-9, the PKA inhibitor H89, or the NF-κB activator lipopolysaccharide (LPS) could abolish the antiproliferative and proapoptotic activities of liraglutide. Additionally, each of these agents could reverse the expression of NF-κB and ABCG2, which was decreased by liraglutide treatment. Furthermore, liraglutide treatment increased the chemosensitivity of pancreatic cancer cells to gemcitabine, as evidenced by in vitro and in vivo experiments. Thus, GLP-1R agonists are safe and beneficial for patients complicated with pancreatic cancer and diabetes, especially for gemcitabine-resistant pancreatic cancer. [ABSTRACT FROM AUTHOR]

Metal salts and 3/4-pyridyltetrazoles (3/4-Hptz) react with oxalic acid (H2ox), 1,2,4,5-benzenetetracarboxylic acid (H4btec), isophthalic acid (H2ip), and 1,2,3,4-butanetetracarboxylic acid (H4btca) to afford six coordination polymers, namely, [Cu(4-ptz)(ox)0.5]n (1), [Cu(4-Hptz)(btec)0.5]n (2), [Co2(3-ptz)(ip)(OH)(H2O)]n (3), {[Co1.5(3-ptz)(btca)0.5(H2O)]·H2O}n (4), {[Co3(4-ptz)2(btca)(H2O)3]·2H2O}n (5), and {[Cd2(4-ptz)2(btca)0.5(H2O)3]·DMF·4H2O}n (6). Their structures were characterized by EA, IR, PXRD, TGA, and single-crystal XRD. 3/4-Pyridyltetrazoles display μ2-, μ3-, and μ5-coordination modes in them. Complex 1 is a 3D MOF constructed from a 2D (4,4) [Cu(4-ptz)]n grid pillared by an oxalate spacer. Complex 2 displays a 2D network containing a square planar Cu1 and elongated octahedral Cu2 centers. Complex 3 shows a 2D network containing μ5-ptz, μ3-ip, and μ3-OH. Complex 4 exhibits a 3D MOF assembled by a 2D [Co1.5(btca)0.5]n network pillared by a 3-ptz spacer. Complex 5 displays a 3D porous MOF with nanosized rectangular tunnels. Complex 6 features a 3D porous MOF built by 2D [Cd2(4-ptz)(btca)0.5]n network pillared by a 4-ptz spacer. Variable-temperature magnetic susceptibility and magneto-structural correlation studies indicate that five CuII/CoII complexes present remarkable magnetic coupling diversity from ferro-, to ferri-, to antiferromagnetic interactions. Complex 1 shows strong antiferromagnetic behavior originating from the oxalate-bridging CuII dimer (Jox = −94.7 cm-1) and the tetrazole-bridging CuII dimer (Jptz = −61.0 cm-1). Complex 2 presents a weak ferromagnetic interaction (J = 0.82 cm-1) originating from the magnetic orbital orthogonality between square planar CuII and octahedral CuII centers. Complex 3 displays ferrimagnetic coupling in the Co3(μ3-OH) triangle. Two btca CoII complexes show antiferromagnetic interactions originating from carboxyl-bridging trinuclear CoII clusters with the θ values of −17.08 K for 4 and −8.6 K for 5. The thermal behaviors of these nitrogen-rich tetrazole complexes are investigated. Anhydrous complexes 1-3 containing rigid polycarboxylates are thermally stable to 250-300 °C and then decompose explosively, whereas complexes 4-6 with flexible butanetetracarboxylate decompose smoothly. [ABSTRACT FROM AUTHOR]

The propagation of surface modes in warm non-magnetized quantum plasma is investigated. The surface modes are assumed to propagate on the plane between vacuum and warm quantum plasma. The quantum hydrodynamic model including quantum diffraction effect (the Bohm potential) and quantum statistical pressure is used to derive a new dispersion relation of surface modes. The new dispersion relation of surface modes is analyzed in some special interesting cases. It is shown that the dispersion relation can be reduced to the earlier results in some special cases. The results indicate that the quantum effects can facilitate the propagation of surface modes in such a semi-bounded plasma system. This work is helpful to understand the physical characteristics of the surface modes and the bounded quantum plasma. [ABSTRACT FROM AUTHOR]

Background: The tumor suppressor gene CDH1 is critical for intercellular adhesion. In our previous work, we reported a nonfunctional CDH1 transcript that lacks the final 83 base pairs of exon 8 (1054del83). In this work, we probed the role of histone epigenetic modifications as well as DNA methylation in selection of this isoform.Methods: RT-qPCR was used to detect CDH1 RNA expression. Methylation of CDH1 was analyzed by bisulphite sequencing PCR. ChIP assay was performed to show histones level. Cell lines were treated with DNA methyltransferase inhibitor AZA, HDAC inhibitor TSA, or siRNA oligonucleotides to test regulation of CDH1 splicing.Results: Greater CDH1 1054del83 transcripts were observed in gastric cancer (GC) cell lines than human gastric mucosal epithelial cell line GES-1. All the cell lines showed significant methylation pattern at the CpG sites of CDH1 exon 8. AZA treatment did not influence selection of 1054del83 transcripts. A significant decrease in acetylation for histones H3 and H4K16Ac in an internal region of the CDH1 gene surrounding the alternative exon 8 were detected in GC cell lines. Treatment with TSA preferentially expressed the correctly spliced transcript and not the exon 8 skipped aberrant transcripts, showing that histone acetylation was involved in the splicing regulation. SiRNA-mediated knockdown of SETD2 (The specific methyltransferase of H3K36) decreased exclusion of exon 8, suggesting that the presence of this mark correlates with increased skipping of the final 83 base pairs of CDH1 exon 8. However, CDH1 splicing was not affected by SRSF2 knockdown.Conclusions: H3K36me3 correlates with increased skipping of the final 83 base pairs of CDH1 exon 8. Histone acetylation was involved in the splicing regulation as well. [ABSTRACT FROM AUTHOR]

Background Although feeding behavior and food habit are ecologically and economically important properties, little is known about formation and evolution of herbivory. Grass carp (Ctenopharyngodon idella) is an ecologically appealing model of vertebrate herbivore, widely cultivated in the world as edible fish or as biological control agents for aquatic weeds. Grass carp exhibits food habit transition from carnivory to herbivory during development. However, currently little is known about the genes regulating the unique food habit transition and the formation of herbivory, and how they could achieve higher growth rates on plant materials, which have a relatively poor nutritional quality. Results We showed that grass carp fed with duckweed (modeling fish after food habit transition) had significantly higher relative length of gut than fish before food habit transition or those fed with chironomid larvae (fish without transition). Using transcriptome sequencing, we identified 10,184 differentially expressed genes between grass carp before and after transition in brain, liver and gut. By eliminating genes potentially involved in development (via comparing fish with or without food habit transition), we identified changes in expression of genes involved in cell proliferation and differentiation, appetite control, circadian rhythm, and digestion and metabolism between fish before and after food habit transition. Upregulation of GHRb, Egfr, Fgf, Fgfbp1, Insra, Irs2, Jak, STAT, PKC, PI3K expression in fish fed with duckweed, consistent with faster gut growth, could promote the food habit transition. Grass carp after food habit transition had increased appetite signal in brain. Altered expressions of Per, Cry, Clock, Bmal2, Pdp, Dec and Fbxl3 might reset circadian phase of fish after food habit transition. Expression of genes involved in digestion and metabolism were significantly different between fish before and after the transition. Conclusions We suggest that the food habit transition from carnivory to herbivory in grass carp might be due to enhanced gut growth, increased appetite, resetting of circadian phase and enhanced digestion and metabolism. We also found extensive alternative splicing and novel transcript accompanying food habit transition. These differences together might account for the food habit transition and the formation of herbivory in grass carp. [ABSTRACT FROM AUTHOR]

A metal-free oxidative cycloaddition reaction of substituted benzamides and alkynes has been developed for the synthesis of isoquinoiones by using bis(trifluoracetoxy)-iodobenzene (PIFA) and trifluoroacetic add (TFA). Under mild conditions, a wide variety of isoquinoiones were conveniently prepared via oxidative annulation of simple N-methoxybenzamide and diarylacetylene or aryl/alkyl acetylene derivatives in yields up to 87%. [ABSTRACT FROM AUTHOR]

We investigated the effects of apocynin on high-fat diet- (HFD-) induced insulin resistance in C57BL/6 mice. After 12 weeks of HFD, the mice that exhibited insulin resistance then received 5 weeks of apocynin (2.4 g/L, in water). Following apocynin treatment, fasting glucose, insulin, and glucose tolerance test showed significant improvement in insulin sensitivity in HFD-fed mice. We demonstrated that serum levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and leptin were remarkably reduced with apocynin treatment. We also found that mRNA expression of TNF-α, IL-6, and monocyte chemoattractant protein-1 (MCP-1) in the liver and mRNA expression of TNF-α, IL-6, MCP-1, and leptin in adipose tissue were suppressed by apocynin. Furthermore, the activity of transcription factor NF-κB in the liver was significantly suppressed with apocynin treatment. These results suggest that apocynin may reduce inflammatory factors in the blood, liver, and adipose tissue, resulting in amelioration of insulin resistance in HFD-fed mice. [ABSTRACT FROM AUTHOR]

Aim To describe the case of a 32-year-old infertile male with small supernumerary marker chromosome (sSMCs) in 80% of peripheral lymphocytes. Methods G-banding, C-banding, STRP analysis, M-FISH and molecule diagnosis of Y-chromosomal microdeletions were performed to determine the origin of sSMCs. Results The karyotype of this patient was established as 47, XY, +mar/46, XY. C-banding showed that the marker chromosome was composed of heterochromatin without visible euchromatic material. No positive result was obtained in STRP, M-FISH and the microdeletion analysis of Y- chromosome. Conclusions The small supernumerary marker chromosome could play a causative role in male infertility although the mechanism remains to be elucidated. [ABSTRACT FROM AUTHOR]

Background: Cross-species nuclear transfer has been shown to be a potent approach to retain the genetic viability of a certain species near extinction. However, most embryos produced by cross-species nuclear transfer were compromised because that they were unable to develop to later stages. Gene expression analysis of cross-species cloned embryos will yield new insights into the regulatory mechanisms involved in cross-species nuclear transfer and embryonic development. Results: A novel gene, K31, was identified as an up-regulated gene in fish cross-subfamily cloned embryos using SSH approach and RACE method. K31 complete cDNA sequence is 1106 base pairs (bp) in length, with a 342 bp open reading frame (ORF) encoding a putative protein of 113 amino acids (aa). Comparative analysis revealed no homologous known gene in zebrafish and other species database. K31 protein contains a putative transmembrane helix and five putative phosphorylation sites but without a signal peptide. Expression pattern analysis by real time RT-PCR and whole-mount in situ hybridization (WISH) shows that it has the characteristics of constitutively expressed gene. Sub-cellular localization assay shows that K31 protein can not penetrate the nuclei. Interestingly, over-expression of K31 gene can cause lethality in the epithelioma papulosum cyprinid (EPC) cells in cell culture, which gave hint to the inefficient reprogramming events occurred in cloned embryos. Conclusion: Taken together, our findings indicated that K31 gene is a novel gene differentially expressed in fish cross-subfamily cloned embryos and over-expression of K31 gene can cause lethality of cultured fish cells. To our knowledge, this is the first report on the determination of novel genes involved in nucleo-cytoplasmic interaction of fish cross-subfamily cloned embryos. [ABSTRACT FROM AUTHOR]

A short-hairpin RNA (shRNA) expression system, based on T7 RNA polymerase (T7RP) directed transcription machinery, has been developed and used to generate a knock down effect in zebrafish embryos by targeting green fluorescent protein ( gfp) and no tail ( ntl) mRNA. The vector pCMVT7R harboring T7RP driven by CMV promoter was introduced into zebrafish embryos and the germline transmitted transgenic individuals were screened out for subsequent RNAi application. The shRNA transcription vectors pT7shRNA were constructed and validated by in vivo transcription assay. When pT7shGFP vector was injected into the transgenic embryos stably expressing T7RP, gfp relative expression level showed a decrease of 68% by analysis of fluorescence real time RT-PCR. As a control, injection of chemical synthesized siRNA resulted in expression level of 40% lower than the control when the injection dose was as high as 2 µg/µl. More importantly, injection of pT7shNTL vector in zebrafish embryos expressing T7RP led to partial absence of endogenous ntl transcripts in 30% of the injected embryos when detected by whole mount in situ hybridization. Herein, the T7 transcription system could be used to drive the expression of shRNA in zebrafish embryos and result in gene knock down effect, suggesting a potential role for its application in RNAi studies in zebrafish embryos. [ABSTRACT FROM AUTHOR]

Sonic hedgehog ( Shh), one of important homologous members of the hedgehog (Hh) family in vertebrates, encodes a signaling molecule that is involved in short- or long-range patterning processes during embryogenesis. In zebrafish, maternal activity of Hh was found to be contributing to the formation of primary motoneurons. However, we found that all of the known Hh members were not maternally expressed in zebrafish. In the present study, full-length cDNA of common carp ( Cyprinus carpio) Shh (cShh) was gained by degenerate reverse-transcription PCR (RT-PCR) and rapid amplification of cDNA ends. Sequence comparison shows that cShh coding sequence shares 93.4% identity with zebrafish Shh coding sequence, and their corresponding protein sequences have 91.9% similarity. Comparative analysis of Shh genomic sequences and Hh protein sequences from different species revealed that the genomic structures of Hh are conserved from invertebrate to vertebrate. In contrast to zebrafish Shh, cShh transcripts were detectable from one-cell stage by RT-PCR analysis. Whole mount in situ hybridization verified the maternal expression of Shh in common carp, which is, to our knowledge, the first report of that in vertebrates, suggesting that Shh might be responsible for the maternal Hh activity in common carp. [ABSTRACT FROM AUTHOR]

In study of gene expression profile in cloned embryos which derived from D. rerio embryonic nuclei and G. rarus enucleated eggs, cytochrome c oxidase subunit I (COXI) of G. rarus, exhibiting difference at expression level between cloned embryos and zebrafish embryo, was cloned. Its full cDNA length is 1654 bp and contains a 1551 bp open reading frame, encoding a 5.64 kDa protein of 516 amino acids. The alignment result shows that mitochondrion tRNAser is co-transcripted with COXI, which just was the 3′-UTR of COXI. Molecular phylogenic analysis based on COXI indicates G. rarus should belong to Gobioninae, which was not in agreement with previous study according to morphological taxonomy. Comparison of DNA with cDNA shows that RNA editing phenomenon does not occur in the COXI of G. rarus. [ABSTRACT FROM AUTHOR]

Some members of hairy/Enhancer-of-split-related gene (HES) family have important effects on axial mesoderm segmentation and the establishment and maintenance of the somite fringe. In fishes, the her6 gene, a member of the HES family, is the homologue of hes1 in mammals and chicken. In this study, the her6 gene and its full-length cDNA from the common carp (Cyprinus carpio) were isolated and characterized. The genomic sequence of common carp her6 is approximately 1.7 kb, with four exons and three introns, and the full-length cDNA of 1314 bp encodes a putative polypeptide of 271 amino acids. To analyse the promoter sequence of common carp her6, sequences of various lengths upstream from the transcription initiation site of her6 were fused to enhanced green fluorescent protein gene (eGFP) and introduced into zebrafish embryos by microinjection to generate transgenic embryos. Our results show that the upstream sequence of 500 bp can direct highly efficient and tissue-specific expression of eGFP in zebrafish embryos, whereas a fragment of 200 bp containing the TATA box and a partial suppressor of hairless paired site sequence (SPS) is not sufficient to drive eGFP expression in zebrafish embryos. [ABSTRACT FROM AUTHOR]

Double-stranded RNA (dsRNA) has been shown to be a useful tool for silencing genes in zebrafish ( Danio rerio), while the blocking specificity of dsRNA is still of major concern for application. It was reported that siRNA (small interfering RNA) prepared by endoribonuclease digestion (esiRNA) could efficiently silence endogenous gene expression in mammalian embryos. To test whether esiRNA could work in zebrafish, we utilized Escherichia coli RNaseIII to digest dsRNA of zebrafish no tail ( ntl) , a mesoderm determinant in zebrafish and found that esi-ntl could lead to developmental defects, however, the effective dose was so close to the toxic dose that esi-ntl often led to non-specific developmental defects . Consequently, we utilized SP6 RNA polymerase to produce si-ntl, siRNA designed against ntl, by in vitro transcription. By injecting in vitro synthesized si-ntl into zebrafish zygotes, we obtained specific phenocopies of reported mutants of ntl. We achieved up to a 59% no tail phenotype when the injection concentration was as high as 4 µg/µL. Quantitative reverse transcription–polymerase chain reaction (RT–PCR) and whole-mount in situ hybridization analysis showed that si-ntl could largely and specifically reduce mRNA levels of the ntl gene. As a result, our data indicate that esiRNA is unable to cause specific developmental defects in zebrafish, while siRNA should be an alternative for downregulation of specific gene expression in zebrafish in cases where RNAi techniques are applied to zebrafish reverse genetics. [ABSTRACT FROM AUTHOR]