To investigate changes of MMP-9 in the rat spleen and hypoxia-induced microvascular basement membrane under high altitude hypoxia. Thirty male specific pathogen-free Sprague Dawley rats were randomly ...divided into control and hypoxia groups, with 15 rats in each group. The rats in the control group were placed in Dingxi City, Gansu Province (2080 m above sea level) for 30 days. Rats in the hypoxia group were raised in a hypoxic environment in Maduo County, Qinghai Province (4300 m above sea level), for 30 days to establish a hypoxic rat model. Routine blood tests, MMP-9 mRNA, MMP-9 protein, and the spleen microvascular basement membrane were detected. (1) Compared with the control group, the red blood cell count, hemoglobin, and hematocrit levels of the rats in the hypoxia group were all increased; thus, a hypoxia model was successfully established. (2) Compared with the control group, the expression of MMP-9 mRNA and protein was significantly higher in the spleen of rats in the hypoxic group, and the difference was statistically significant (P <0.05). (3) Compared with the control group, the blood vessel basement membrane in the spleen of the hypoxia group was degraded. Under natural low air pressure and high altitude conditions, the expression of MMP-9 in rat spleen tissue increases and participates in the degradation of the microvascular basement membrane.
Cosmic Tidal Reconstruction in Redshift Space Zang 臧, Shi-Hui 诗慧; Zhu 朱, Hong-Ming 弘明; Schmittfull, Marcel ...
The Astrophysical journal,
02/2024, Volume:
962, Issue:
1
Journal Article
Peer reviewed
Open access
Abstract
Gravitational coupling between large- and small-scale density perturbations leads to anisotropic distortions to local small-scale matter fluctuations. Such local anisotropic distortions can ...be used to reconstruct large-scale matter distribution, known as tidal reconstruction. In this paper, we apply the tidal reconstruction methods to simulated galaxies in redshift space. We find that redshift-space distortions (RSDs) lead to anisotropic reconstruction results. While the reconstructed radial modes are more noisy mainly due to the small-scale velocity dispersion, the transverse modes are still reconstructed with high fidelity, and well correlated with the original large-scale density modes. The bias of the reconstructed field at large scales shows a simple angular dependence, which can be described by a form similar to that of the linear RSD. The noise power spectrum is nearly isotropic and scale independent on large scales. This makes the reconstructed tide fields an ideal tracer for cosmic variance cancellation and multi-tracer analysis and has profound implications for future 21 cm intensity mapping surveys.
Perfect matching of an assembled physical sequence to a specified designed sequence is crucial to verify design principles in genome synthesis. We designed and de novo synthesized 536,024-base pair ...chromosome synV in the "Build-A-Genome China" course. We corrected an initial isolate of synV to perfectly match the designed sequence using integrative cotransformation and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9)-mediated editing in 22 steps; synV strains exhibit high fitness under a variety of culture conditions, compared with that of wild-type V strains. A ring synV derivative was constructed, which is fully functional in
under all conditions tested and exhibits lower spore viability during meiosis. Ring synV chromosome can extends Sc2.0 design principles and provides a model with which to study genomic rearrangement, ring chromosome evolution, and human ring chromosome disorders.
Spatial omics facilitate an in-depth understanding of cell states and cell interactions. Recent work by Zhang et al. simultaneously seizes spatial epigenetic priming, differentiation, and gene ...regulation at nearly single-cell resolution by developing an epigenome–transcriptome comapping technology. This work displays how epigenetic features influence cell dynamics and transcriptional phenotypes at spatial and genome-wide levels.
•Microbial fermentation is the key factor controlling the quality of dark tea.•Serial reactions modify the chemical constituents of tea leaves during fermentation.•Multi-omics approaches are used to ...reveal microbial impact on dark tea quality.
Dark tea is a unique fermented tea produced by solid-state fermentation of tea leaves (Camellia sinensis). It includes ripe Pu-erh tea, Fu brick tea, Liupao tea, and other teas. Microbial fermentation is considered to be the key factor controlling the quality of dark tea. It involves a series of reactions that modify the chemical constituents of tea leaves. These chemical conversions during microbial fermentation of dark tea are associated with a variety of functional core microorganisms. Further, Multi-omics approaches have been used to reveal the microbial impact on the conversion of the chemical components in dark tea. In the present review, we provide an overview of the most recent advances in the knowledge of the microbial bioconversion of the chemical components in dark tea, including the chemical composition of dark tea, microbial community composition and dynamics during the fermentation process, and the role of microorganisms in biotransformation of chemical constituents.
Fu brick tea (FBT) is a microbial-fermented tea, which is produced by the solid-state fermentation of tea leaves. Previous studies have proved that FBT aqueous extracts could attenuate obesity and ...gut microbiota dysbiosis. However, the bioactive components in FBT that contribute to these activities remain unclear. In this study, we aimed to investigate the effects of FBT polyphenols (FBTPs) on obesity, gut microbiota, and gut microbiota-related intestinal oxidative stress and barrier function and to further investigate whether the antiobesity effect of FBTPs was dependent on the alteration of gut microbiota. The results showed that FBTP supplementation effectively attenuated obesity in high-fat diet (HFD)-fed rats. FBTP supplementation improved the intestinal oxidative stress and intestinal barrier function, including intestinal inflammation and the integrity of the intestinal barrier. Furthermore, FBTP intervention significantly attenuated HFD-induced gut microbiota dysbiosis, characterized by increased phylogenetic diversity and decreased Firmicutes/Bacteroidetes ratio. Certain core microbes, including Akkermansia muciniphila, Alloprevotella, Bacteroides, and Faecalibaculum, were also found to be improved by FBTPs. Moreover, the antiobesity effect of FBTPs was gut microbiota-dependent, as demonstrated by a fecal microbiota transplantation experiment. Collectively, we concluded that FBTPs reduced obesity by modulating the gut microbiota and gut microbiota-related intestinal oxidative stress and barrier function. Therefore, FBTPs may be used as prebiotic agents to treat obesity and gut microbiota dysbiosis in obese individuals.
With the environmental deterioration caused by the advance of climate change, soil salinization is a serious and growing global problem. Currently about 7% of the world's land surface is threatened ...by salinization. China is a country whose soils are severely affected by this problem, which, due to its extensive area, and wide distribution poses a serious threat to regional agricultural development. In this review, we summarize the framework for soil salinization research in China over the past 70 years, assess the weaknesses of existing research in both a domestic and international context, highlight the trends and key findings of global research about saline soils over the past 30 years, and propose six major fields and directions for future research on saline soil.
We report the optical properties of tetraphenylethene (TPE) and other TPE derivatives functionalised with an octyl group (TPE‐OCT) and polyethyleneglycol group (TPE‐PEG) in the side chain. We ...compared TPE‐OCT and TPE‐PEG with TPE in both organic solvents and under aqueous conditions. All materials exhibit aggregation‐induced emission, however, uncommonly, TPE‐PEG seems to aggregate in aqueous solution with enhanced photoluminescence quantum efficiency (PLQE) relative to that in organic solvents. All three materials can be photo‐oxidised in solution to their diphenylphenanthrene derivative by irradiation with UV light (at both ≈1 and ≈5 mW cm−2), with a subsequent enhancement in PL efficiency. The electron‐donating ether group increases the rate of oxidation relative to bare TPE and also photo‐oxidation was shown to be solvent and concentration dependent. Finally, photo‐oxidation was also demonstrated in the aggregate state.
Photo finish: The optical properties and photo‐oxidation of tetraphenylethene (TPE) and its derivatives in solution, the nanoparticle state and in a PMMA matrix are discussed (see scheme). This demonstration should be useful in encouraging the design of more photostable TPE molecules, which are commonly used in biosensing and imaging research.
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•Dilute NaOH supplemented with H2O2 pretreatment was successfully employed to GW.•The pretreated GW showed high holocellulose recovery under mild condition.•The process exhibited ...synergistic effect on lignin removal and enzymolysis.•High titers of ethanol from the pretreated GW was achieved by SSCF.
Pretreatment process plays a key role in biofuel production from lignocellulosic feedstocks. A study on dilute NaOH pretreatment supplemented with H2O2 under mild condition was conducted to overcome the recalcitrance of grass waste (GW). The optimized process could selectively increase lignin removal (73.2%), resulting in high overall recovery of holocellulose (73.8%) as well as high enzymolysis efficiency (83.5%) compared to H2O2 or NaOH pretreatment. The analyses by Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) revealed that supplementary H2O2 disrupted the structure of GW to facilitate the removal of lignin by NaOH, and exhibited synergistic effect on lignin removal and enzymolysis with dilute NaOH. Moreover, high titer of ethanol (100.7 g/L) was achieved by SSCF on 30% (w/v) pretreated GW loading. The present study suggests that the established synergistic pretreatment is a simple, efficient, and promising process for GW biorefinery.
Metal–organic framework (MOF) glasses are a fascinating new class of materials, yet their prosperity has been impeded by the scarcity of known examples and limited vitrification methods. In the work ...described in this report, we applied synergistic stimuli of vapor hydration and thermal dehydration to introduce structural disorders in interpenetrated dia -net MOF, which facilitate the formation of stable super-cooled liquid and quenched glass. The material after stimulus has a glass transition temperature (T g) of 560 K, far below the decomposition temperature of 695 K. When heated, the perturbed MOF enters a super-cooled liquid phase that is stable for a long period of time (>104 s), across a broad temperature range (26 K), and has a large fragility index of 83. Quenching the super-cooled liquid gives rise to porous MOF glass with maintained framework connectivity, confirmed by EXAFS and PDF analysis. This method provides a fundamentally new route to obtain glassy materials from MOFs that cannot be melted without causing decomposition.