•Ecosystem invasibility to a nonnative invasive species can be quantified through metrics measuring ecosystem structure.•In a landscape managed by frequent, low-intensity prescribed fires, pine ...flatwoods are more susceptible to Chinese tallow invasion than pine savannas.•High invasibility of pine flatwoods is mainly attributed to its high overstory basal area but low understory shrub cover.•Short fire intervals increase invasion probability, but the impact of fire on tallow changes with invasion stages.•Short fire intervals promote the recruitment of tallow seedlings and saplings; while long fire intervals favor the development of large trees.
The Chinese tallow tree (Triadica sebifera, hereafter, tallow) is a nonnative invasive species that has invaded diverse ecosystems including forests, prairies and wetlands in the Gulf Coastal Plain of the southeastern United States. We proposed a landscape (ecosystem)-level modeling framework of tallow invasion and applied it to a fire-managed landscape to evaluate the effect of prescribed fire on tallow invasion and ecosystem invasibility. A spatially random sample consisting of 55 0.04-ha circular plots was installed in a landscape of appropriately 2,900 ha in the Mississippi Sandhill Crane National Wildlife Refuge in 2015. These plots, plus ten additional tallow-invaded plots from another study were measured in May-June of 2015 and remeasured in November of 2018. Across the entire landscape, pine flatwoods (invasion probability = 0.52) were generally more susceptible to tallow invasion than pine savannas (invasion probability = 0.16) (p = 0.002), and the former had a greater number of tallow seedlings and saplings (p < 0.001), but fewer large tallow trees (p = 0.07) than the latter. The effect of fire on tallow invasion is two-fold and changes with fire return intervals and ecosystem conditions. Fire may promote seed germination and seedling recruitment, but recurrent fires top-kill or even completely kill young seedlings and saplings. Large proportions of invaded plots and abundant tallow seedlings and saplings that accumulate in pine flatwoods are essentially attributed to their high overstory tree basal area but relatively low shrub/grass coverage. On sites near roadways or with tallow seed trees, short fire intervals tend to increase invasion probability and the abundance of tallow seedlings and saplings, whereas long fire intervals increase the abundance of large tallow trees. Under current fire treatments, pine flatwoods are more susceptible to seedling colonization and sapling establishment, while pine savannas favor the growth and development of large tallow trees.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Canopy closure, grass cover, and elevation affected spatial variations of soil tallow seed banks.•The number of new tallow germinants was negatively correlated with the cover of litter and ...shrubs.•Tallow seedling recruitment rates increased linearly with fire intensity.•No difference in survived seedlings existed in burned and unburned areas the second year post-fire.
Prescribed fire has been increasingly used in restoring endangered slash pine (Pinus elliottii) flatwood ecosystems in the southeastern United States. We collected overstory and understory data to study the impact of fire on the post-invasion spread of Chinese tallow tree (Triadica sebifera) in a wet slash pine flatwood in the Grand Bay National Wildlife Refuge, Mississippi, USA. A total of 70 contiguous 30-m2 quadrats were installed and measured prior to fire (2018) and remeasured post-fire (2019 and 2020) to study the spatial distribution of the tallow soil seedbank and seedling recruitment. In addition, the same data were collected around 11 randomly selected tallow seed trees with varying burn intensities (estimated by stem-bark char heights) to evaluate the changes in seedling recruitment and survial by burn intensity. Soil tallow seedbanks around seed trees (427.7 ± 43.9 seeds m−2) were significantly greater than elsewhere (34.6 ± 13.2 seeds m−2) (p < 0.001). Tallow’s soil seedbank varied spatially with more tallow seeds confined in areas with low elevation, canopy closure, and grass cover. Tallow seedling density was negatively correlated with litter and shrub cover; seedling recruitment rates increased with fire intensity with the mean seedling:seed ratio averaging 0.25 in burned areas, significantly higher than that in unburned areas (0.01–0.02). However, most germinants died by the end of the second year, resulting in nonsignificant differences in the density and height of surviving seedlings between burned and unburned areas. These findings suggest that prescribed fire is an effective management tool for depleting the tallow seedbank while not contributing to post-invasion spread.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This systematic analysis aims to assess the efficacy of PD-1/PD-L1 blockades compared with non-PD-1/PD-L1 therapy and investigate the potential predictive factors in epithelial carcinoma patients.
A ...total of 11 trials with 6716 patients of melanoma, non-small cell lung cancer (NSCLC) and renal cell carcinoma (RCC) were included. The pooled HRs (95%CI) were 0.67 (0.62, 0.73), p < 0.001 for OS and 0.66 (0.57, 0.76), p < 0.001 for PFS. In subgroup analyses, HRs were 0.58 (0.50, 0.66), p < 0.001 in PD-L1 ≥ 1% group, 0.75 (0.63, 0.89), p = 0.001 in PD-L1 < 1% group for OS and 0.59 (0.48, 0.72), p < 0.001 in PD-L1 ≥ 1% group, 0.80 (0.59, 1.07), p = 0.136 in PD-L1 < 1% group for PFS. The p values of pooled HRs for OS in different age, sex and ECOG score groups were less than 0.001. In NSCLC patients, aggregated HRs for OS were 1.40 (0.92, 2.12), p = 0.114 in EGFR mutant group and 0.88 (0.59, 1.32), p = 0.536 in never smokers.
A systematic search from January 2010 to April 2016 was conducted for eligible clinical trials. Based on the data of hazard ratios (HRs) and 95% confidence intervals (CIs) for overall survival (OS) and progression-free survival (PFS), we assessed the pooled HRs and proposed the subgroup analyses.
PD-1/PD-L1 blockades prolonged OS and PFS in epithelial carcinoma patients. PD-L1 expression was a predictive factor for PFS but not predictive for OS. Age, sex and ECOG score were excluded to predict any of the efficacy endpoints. Smoking history and EGFR wild type were associated with extended OS in NSCLC patients.
The northeastern Tibetan Plateau (NETP) is the most intensely uplifted deformation region in the Tibetan Plateau. The intense gas release caused by uplift has attracted widespread attention. In this ...study, we measured the soil gas concentrations (Rn and CO2) and CO2 fluxes from active faults and analysed the seismic tomography in the arcuate structure zone of the NETP. The results reveal that the concentrations and fluxes of Rn and CO2 in the south area are higher than those in the north area. Factors such as rock types, meteorological conditions, and seismicity have limited influence on soil gas emissions. Instead, the uplift of the upper crust in the Tibetan Plateau plays a crucial role in determining the distribution of soil gases. Regions with high crack density (ε), saturation rate (ξ) and Poisson's ratio (σ) in the upper crust show stronger release, such as the epicenter of the Haiyuan MS 8.5 earthquake. The convergence zone of the arcuate structure zone with high crust uplift velocity is an intense release area with a rough total CO2 output of ∼1.10 Mt.·yr−1. This output is twice the annual CO2 output of the Wenchuan MS 8.0 earthquake rupture and one-fifth of the annual CO2 output of Amiata volcano, Italy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
As an emerging feed additive extracted from the traditional herb milk thistle, silybin has few applications and studies in Peking ducks. The aim of this study was to explore the practical ...significance of silymarin application in Peking ducks and to provide more theoretical support for the application of silymarin in livestock and poultry production. A total of 156 1-day-old healthy Peking ducks were randomly divided into four groups and supplemented with 0 mg/kg (control group), 400 mg/kg (S400), 800 mg/kg (S800) and 1,600 mg/kg (S1600) of silybin in the diets at day 14, to investigate the effects of silymarin on the growth, serum indexes and liver transcriptome of Peking ducks. The whole experiment lasted until day 42, and the sample collection was scheduled to take place in the morning. A substantial inprovement in average daily gain (ADG) and a decrease in feed conversion ratio (FCR) occurred in the S1600 group on days 14-28 compared to the control group (
< 0.05). The FCRs of other additive groups in the same period showed the same results. Supplementation of diets with silybin significantly increased serum IgA levels and when 1,600 mg/kg of silybin was given, levels of TNF-α and IL-6 were also significantly decreased (
< 0.05). In addition, we observed that the S1600 group had a significantly lower (
< 0.05) glutamine transaminase and an increased (
< 0.05) T-SOD level in the S400 group (
< 0.05). Liver transcriptome sequencing showed that 71 and 258 differentially expressed genes (DEGs) were identified in the S400 and S1600 groups, respectively, compared with the control group. DEGs related to cell composition and function, antigen processing and presentation were up-regulated, while DEGs related to insulin resistance and JAK-STAT were down-regulated. Conclusively, silybin can be used as a feed additive to improve the growth performance and health status of Peking ducks.
Weaning is undoubtedly one of the most crucial stages in the growth and development of all mammalian animals, including donkey foals. Weaning is a dynamic and coordinated process of the body, which ...is closely associated with the health, nutrition, and metabolism of the host. Many studies have shown that the intestinal microbiota and serum metabolites of mammals exhibit different changes during lactation, weaning, and postweaning. However, the alterations in serum metabolites in donkey foals before and postweaning and the correlation between serum metabolites and intestinal microbiota are largely unknown. This study is based on the fecal 16S rRNA and serum metabolomes of Dezhou donkey foals. In total, 10 samples (fecal and serum) were collected during the following three stages: before weaning (F.M.1), during weaning (F.M.3), and postweaning (F.M.6). To study the alterations in intestinal microflora, serum metabolites, and their correlation before and postweaning. We found that with the growth and weaning progress of donkey foals, the intestinal microbiota of donkey foals underwent obvious changes, and the diversity of fecal bacteria increased (Chao1 and Shannon indexes). The main intestinal microbial flora of donkey foals include Bacteroides and Firmicutes. We found many microbiota that are associated with immunity and digestion in the postweaning group, such as
,
,
,
, and
, which can be considered microbial markers for the transition from liquid milk to solid pellet feed.
and
can produce organic acids, including butyric acid and acetic acid, which are crucial for regulating the intestinal microecological balance of donkeys. Furthermore, the metabolome showed that the serum metabolites enriched before and postweaning were mainly related to arachidonic acid metabolism and riboflavin metabolism. Riboflavin was associated with the development of the small intestine and affected the absorption of the small intestine. We also found that the changes in the gut microbiome of the foals were significantly correlated with changes in serum metabolites, including lysophosphatidylcholine (LPC; 12,0) and positively correlated with
and
. To summarize, this study provides theoretical data for the changes in the intestinal microbiome and serum metabolism during the entire weaning period of donkey foals.
Tumor metastasis is an intricate multistep process regulated via various proteins and enzymes modified and secreted by swollen Golgi apparatus in tumor cells. Thus, Golgi complex is considered as an ...important target for the remedy of metastasis. Currently, Golgi targeting technologies are mostly employed in Golgi-specific fluorescent probes for diagnosis, but their applications in therapy are rarely reported. Herein, we proposed a prodrug (INR) that can target and destroy the Golgi apparatus, which consisted of indomethacin (IMC) as the Golgi targeting moiety and retinoic acid (RA), a Golgi disrupting agent. The linker between IMC and RA was designed as a hypoxia-responsive nitroaromatic structure, which ensured the release of the prototype drugs in the hypoxic tumor microenvironment. Furthermore, INR could be assembled with pirarubicin (THP), an anthracycline, to form a carrier-free nanoparticle (NP) by emulsion-solvent evaporation method. A small amount of mPEG2000-DSPE was added to shield the positive charges and improve the stability of the nanoparticle to obtain PEG-modified nanoparticle (PNP). It was proved that INR released the prototype drugs in tumor cells and hypoxia promoted the release. The Golgi destructive effect of RA in INR was amplified owing to the Golgi targeting ability of IMC, and IMC also inhibited the protumor COX-2/PGE2 signaling. Finally, PNP exhibited excellent curative efficacy on 4T1 primary tumor and its pulmonary and hepatic metastasis. The small molecular therapeutic prodrug targeting Golgi apparatus could be adapted to multifarious drug delivery systems and disease models, which expanded the application of Golgi targeting tactics in disease treatment.
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IJS, KILJ, NUK, PNG, UL, UM
The general anesthesia associated with long-term cognitive impairment has been causing the concern of the whole society. In particular, repeated anesthetic exposures may affect executive function, ...processing speed, and fine motor skills, which all directly depended on the functions of oligodendrocytes, myelin, and axons. However, the underlying mechanisms are still largely unknown. To investigate the spatial and temporal alterations in oligodendrocytes in the corpus callosum (CC) and hippocampus following repeated sevoflurane exposures (3%, for 2 h) from postnatal day 6 (P6) to P8, we used immunofluorescence, Western blot, and a battery of behavioral tests. As previously stated, we confirmed that early anesthetic exposures hampered both cognitive and motor performance during puberty in the rotarod and banes tests. Intriguingly, we discovered that the proliferation of oligodendrocyte progenitor cells (OPCs) was immediately enhanced after general anesthesia in the CC and hippocampus from P8 to P32. From P8 through P15, the overall oligodendrocyte population remained constant. However, along with the structural myelin abnormalities, the matured oligodendrocytes statistically reduced in the CC (from P15) and hippocampus (from P32). Administration of clemastine, which could induce OPC differentiation and myelin formation, significantly increased matured oligodendrocytes and promoted myelination and cognition. Collectively, we first demonstrated the bi-directional influence of early sevoflurane exposures on oligodendrocyte maturation and proliferation, which contributes to the cognitive impairment induced by general anesthesia. These findings illustrated the dynamic changes in oligodendrocytes in the developing brain following anesthetic exposures, as well as possible therapeutic strategies for multiple general anesthesia associated cognitive impairment.
•Repeated sevoflurane anesthesia on developing brain could immediately enhance the proliferation of OPCs.•Repeated sevoflurane exposures decreased the numbers of OLs in corpus callosum and hippocampus.•The reduction of OLs by sevoflurane exposure occurred earlier in the corpus callosum than in the hippocampus.•Repeated sevoflurane exposure impaired motor coordination and cognitive function.•Drug-based strategy could improve myelination and functional recovery.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The phenomenon of semantic satiation, which refers to the loss of meaning of a word or phrase after being repeated many times, is a well-known psychological phenomenon. However, the microscopic ...neural computational principles responsible for these mechanisms remain unknown. In this study, we use a deep learning model of continuous coupled neural networks to investigate the mechanism underlying semantic satiation and precisely describe this process with neuronal components. Our results suggest that, from a mesoscopic perspective, semantic satiation may be a bottom-up process. Unlike existing macroscopic psychological studies that suggest that semantic satiation is a top-down process, our simulations use a similar experimental paradigm as classical psychology experiments and observe similar results. Satiation of semantic objectives, similar to the learning process of our network model used for object recognition, relies on continuous learning and switching between objects. The underlying neural coupling strengthens or weakens satiation. Taken together, both neural and network mechanisms play a role in controlling semantic satiation.
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