Karst fissures mitigate the negative effects of drought on plant growth and photosynthetic physiology.

Hard limestone substrates, which are extensively distributed, are believed to exacerbate drought and increase the difficulty of restoration in vulnerable karst regions. Fissures in such substrates may alleviate the negative effect of drought on plants, but the underlying mechanisms remain poorly understood. In a two-way factorial block design, the growth and photosynthesis of 2-year-old Phoebe zhennan seedlings were investigated in two water availabilities (high versus low) and three stimulated fissure habitat groups (soil, soil-filled fissure and non-soil-filled fissure). Moreover, the fissure treatments included both small and big fissures. Compared to the soil group, the non-soil-filled fissure group had decreased the total biomass, root biomass, total root length, and the root length of fine roots in the soil layer at both water availabilities, but increased net photosynthetic rate (Pn) and retained stable water use efficiency (WUE) at low water availability. However, there were no significant differences between the soil-filled fissure group and soil group in the biomass accumulation and allocation as well as Pn. Nevertheless, the SF group decreased the root distribution in total and in the soil layer, and also increased WUE at low water availability. Across all treatments, fissure size had no effect on plant growth or photosynthesis. Karst fissures filled with soil can alleviate drought impacts on plant root growth, which involves adjusting root distribution strategies and increasing water use efficiency. These results suggest that rock fissures can be involved in long-term plant responses to drought stress and vegetation restoration in rocky mountain environments under global climate change.

Intestinal microbiota in the treatment of metabolically associated fatty liver disease.

Metabolically associated fatty liver disease (MAFLD) is a common cause of chronic liver disease, the hepatic manifestation of metabolic syndrome. Despite the increasing incidence of MAFLD, no effective treatment is available. Recent research indicates a link between the intestinal microbiota and liver diseases such as MAFLD. The composition and characteristics of the intestinal microbiota and therapeutic perspectives of MAFLD are reviewed in the current study. An imbalance in the intestinal microbiota increases intestinal permeability and exposure of the liver to adipokines. Furthermore, we focused on reviewing the latest "gut-liver axis" targeted therapy.

[Color quantification and evaluation of landscape aesthetic quality for autumn landscape forest based on visual characteristics in subalpine region of western Sichuan, China]. / 基于视觉特性的川西亚高山秋季景观林色彩量化及景观美学质量评价.

Evaluation of landscape aesthetic quality is a key step in the management system of forest resource. Color is an important component of autumn landscape forest, and quantitative analysis of color and scientific evaluation of landscape aesthetic quality are important for the management of autumn landscape forest. We assessed the aesthetic quality of autumn landscape forest using scenic beauty estimation and analyzed the effects of color characteristics on ornamental value of autumn landscape forest based on color composition and color spatial pattern according to human's visual characteristics. The results showed that the overall landscape quality of subalpine region of western Sichuan could be divided into five grades according to beauty value (I to V). About 71.5% of autumn landscape forests could be classified into grade I, II, and III, indicating that autumn landscape forests of subalpine region in western Sichuan had higher ornamental value. According to the scenic beauty estimation value, the landscape aesthetic quality of broadleaved mixed forests was higher than that of coniferous and broadleaved mixed forests and pure forests. In terms of the comprehensive index evaluation system of color elements, the index weight coefficient order was landscape patch heterogeneity factors>autumn main color factors>color saturation and brightness factors>color diversity and evenness factors. With cluster analysis, autumn landscape forests of western Sichuan could be divided into three types. The forests with higher ornamental value showed following characteristics: larger degree of patch fragmentation and heterogeneity, higher percentage of orange and yellow and lower percentage of green in autumn, higher percentage of color saturation and brightness, and higher color diversity and uniformity index. The communities with higher richness, species diversity and evenness index would have higher beauty values. We concluded that species diversity and fragmentation of colors should be considered in the construction of autumn landscape forests, and that aesthetic quality of autumn landscape forest could be improved by planting and cultivating tree species with various and bright autumn leaf colors.

Ameliorative effects of glycine in an experimental nonalcoholic steatohepatitis and its correlation between TREM-1 and TREM-2.

Inflammation plays an important role in Nonalcoholic Steatohepatitis (NASH), triggering receptor expressed on myeloid cells-1 and 2 (TREM-1 and TREM-2) modulates inflammatory and innate immune, they have been investigated in various inflammatory diseases, but not in NASH. Meanwhile we added glycine in HFO (HFOG) to investigate if the liver pathologic relief is related with TREM-1 and TREM-2. Liver tissue staining and serum indexes showed that the NASH was successful from the 4(th) weekend and glycine can improved many features of NASH. Results from Q-PCR and ELISA study showed that compareaded with control, TREM-1 is upregulated and TREM-2 is downregulated respectively in 4 and 8-week NASH model (TREM-1: p < 0.001; TREM-2: p < 0.001).Compared with HFO group, HFOG group with an extra 5% Glycine into the diet of NASH, we found that all model liver pathologic and serum indexes ameliorated in this group. Furthermore, Results from Q-PCR and ELISA study showed that compareaded with HFO group, TREM-2 of this group is upregulated and TREM-1 is downregulated respectively from the 4(th) weekend, which is more significant at the 8(th) weekend (TREM-1: p <0.001; TREM-2: p =0.048). Pearson correlation showed that TREM-1 and TREM-2 were closely associated with serum ET, TNF-α, TLR-4 and PC III. Besides, using multiple-stepwise regression analysis, we found that the ameliorative effects of glycine in HFOG was mainly related to its counteraction of PC III, TREM-1 and upregulation of TREM-2. Furthermore, we detected the expression of TREM-1 and TREM-2 in gall stone patients without drinking excessively before undergoing cholecystectomy, and found that the rise of TREM-1 and reduction of TREM-2 was close associated with the severity of fatty liver. To conclude, our results support the concept that TREM-1 and TREM-2 were close strongly linked to NASH and NALFD. Glycine can relieve NASH by its anti-fibrosis effect, and this ameliorative effect is related to the expression change of TREM-1/2 to some extent.

Winners always win: growth of a wide range of plant species from low to future high CO2.

Evolutionary adaptation to variation in resource supply has resulted in plant strategies that are based on trade-offs in functional traits. Here, we investigate, for the first time across multiple species, whether such trade-offs are also apparent in growth and morphology responses to past low, current ambient, and future high CO 2 concentrations. We grew freshly germinated seedlings of up to 28 C3 species (16 forbs, 6 woody, and 6 grasses) in climate chambers at 160 ppm, 450 ppm, and 750 ppm CO 2. We determined biomass, allocation, SLA (specific leaf area), LAR (leaf area ratio), and RGR (relative growth rate), thereby doubling the available data on these plant responses to low CO 2. High CO 2 increased RGR by 8%; low CO 2 decreased RGR by 23%. Fast growers at ambient CO 2 had the greatest reduction in RGR at low CO 2 as they lost the benefits of a fast-growth morphology (decoupling of RGR and LAR [leaf area ratio]). Despite these shifts species ranking on biomass and RGR was unaffected by CO 2, winners continued to win, regardless of CO 2. Unlike for other plant resources we found no trade-offs in morphological and growth responses to CO 2 variation, changes in morphological traits were unrelated to changes in growth at low or high CO 2. Thus, changes in physiology may be more important than morphological changes in response to CO 2 variation.

[Effects of drought stress and re-watering on the active oxygen scavenging system of Cupressus funebris seedlings in Karst area].

This paper studied the active oxygen scavenging system of Cupressus funebris seedlings under drought condition and the recovery capability of the system after re-watering, aimed to understand the adaptation mechanisms of C. funebris to the 'drought and re-watering' environment in Karst area. With the increasing time of drought stress, the seedling's relative water content (RWC) decreased, soluble protein concentration increased first and decreased then, and malondialdehyde (MDA) content increased consistently. The MDA content recovered to the level of the control (CK) when re-watering was implemented within 2 weeks of drought, but could not when the re-watering was made after 4 and 6 weeks of drought. Under drought stress, the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) increased consistently. After rewatering, the SOD activity had somewhat decrease but still remained at a higher level than the CK, and the POD and CAT activities decreased to the CK level when suffered mild stress but had less decrement when suffered severe stress. It was concluded that C. funebris seedlings could resist mild drought stress via increasing their soluble protein concentration and inhibiting membrane lipid peroxidation, but could not resist severe drought stress because of the irreversible damage of their membrane structure.

A novel strategy for engineering vascularized grafts in vitro.

Tissue engineering is an interdisciplinary field promising new therapeutic means for replacing lost or severely damaged tissues or organs. However, the fabrication of complex engineered tissues has been hampered due to the lack of vascularization to provide sufficient blood supply after implantation. In this article, we propose using rapid prototyping technology to prefabricate a scaffold with an inside hollowed vascular system including an arterial end, a venous end and capillary networks between them. The scaffold will be ''printed'' layer by layer. When printing every layer, a ''low-melting point'' material will be used to form a blood vessel network and a tissue-specific material will be used outside it. Hereafter the 'low-melting point' material will be evacuated by vaporization to ensure a hollowed vessel network. Then the inside hollowed capillary network can be endothelialized by using autologous endothelial cells in a cycling bioreactor while the outside material can be embedded with tissue-special cells. In the end, the new vascularized autologous grafts could be transferred to the defect site by using microsurgical techniques to connect the grafts with the host artery and vein. The strategy would facilitate construction of complex tissue engineering if the hypothesis proved to be practical.

Dynamic changes and mechanism of intestinal endotoxemia in partially hepatectomized rats.

AIM: To explore the mechanism of intestinal endo-toxemia (IETM) formation and its changes in partially hepatectomized (PH) rats. METHODS: One-hundred and two adult male Wistar rats were randomly divided into three groups: normal control (NC) group, partially hepatectomized (PH) group and a sham-operated (SO) group. To study the dynamic changes, rats were sacrificed before and at different time points after partial hepatectomy or the sham-operation ( 6 h, 12 h, 24 h, 36 h, 48 h, 72 h, 120 h and 168 h). NC group was used as 0 h time point in observation, namely 0 h group. For each time point indicated, six rats were used in parallel. Endotoxin (ET) and diamine oxidase (DAO) levels were determined in serum using Limulus Lysate test with chromogenic substrate and spectrophotometry. Intestinal mucosa barrier was observed under optical or electron microscope. The number and functional state of Kupffer cells (KCs) in the remnant regenerating liver were measured by immunohistochemical staining. RESULTS: Serum ET levels significantly increased during 6-72 h period after PH compared with NC and SO groups, and there were two peak values at 12 and 48 h while serum DAO level significantly increased at 12 and 24 h. There was positive correlation (r = 0.757, P < 0.05) between the levels of DAO and ET dynamic changes. The optical examination showed neutrophil margination and superficial necrosis of the villi in the intestinal mucosa during 6-24 h period after PH. The penetrated electron microscope examination showed that the gaps between intestinal mucosa cells were increased and the Lanthanum (La) particles were observed among the intestinal mucosa cells during 6-48 h period. The numbers of KCs in the remnant regenerating liver were significantly increased during 24-168 h period after PH. However, the activation of KCs was predominantly observed at 48 h after PH. CONCLUSION: The mechanism of IETM in PH rats might be the injury of intestinal mucosa barrier and the decrease of the absolute number of KCs as well as the depression of functional state of KCs. This observation is of potential value in patients undergoing liver resection.

[Growth response of Broussonetia papyrifera seedlings to VA mycorrhizal fungi inoculation].

In an experiment with single inoculation (SI) and co-inoculation (CI) of three VA mycorrhizal fungi, i. e., Glomus mosseea (GM), Glomus versiforme (GV) and Glomus diaphanum (GD), the growth response of Broussonetia papyrifera seedlings in limestone area was studied. The results showed that after 3 months of growth, the aboveground-, underground-, and total biomass were increased significantly by the inoculation, being 2.49-8.19 times as much as the control. Treatment CI had the highest biomass, but the leaf number had little difference with the control. In SI, GD inoculation had the greatest effect; and CI was more effective than SI. The ground diameter, height, and total leaf area in CI were 1.5, 2.2, and 6.0 times as much as those in CK, respectively, and the root/shoot ratio in CI was the highest (0.446). There existed an interactive selection between host plants and VA mycorrhizal fungi.

[Effect of serum autoantibodies against the M2 muscarinic acetylcholine receptors from patients with heart failure on L-Type Ca2+ channel activity in guinea pig cardiac myocytes].

OBJECTIVE: To investigate the effect of serum autoantibodies against the human M(2) muscarinic acetylcholine receptors (M(2)-receptors, Abs) from patients with congestive heart failure on L-Type Ca(2+) channel activity in guinea pig cardiac myocytes. METHOD: Using whole cell patch-clamp technique, we quantitatively measured the ionic intensity and density of L-Type Ca(2+) channel (I(Ca-L)). RESULTS: The M(2)-receptors agonist (carbachol) could decrease the I(Ca-L) peak intensity and density stimulated by isoprenaline from (2111.65 +/- 203.13) pA and (18.83 +/- 1.14) pA/pF to (1230.87 +/- 208.14) pA (P < 0.01) and (10.72 +/- 1.06) pA/pF (P < 0.01). The serum Abs could also decrease I(Ca-L) peak intensity and density [from (1995.21 +/- 195.13) pA and (18.13 +/- 1.03) pA/pF to (636.42 +/- 110.07) pA (P < 0.01) and (5.54 +/- 0.81) pA/pF, P < 0.01]. The M(2)-receptors antagonist, atropine was able to block these effects of carbachol and Abs. CONCLUSIONS: The circulating serum autoantibodies against the M(2)-receptors has similar effect as M(2)-receptors agonist on decreasing the isoprenaline stimulated I(Ca-L) in guinea pig cardiac myocytes and possess negative inotropic effect. These results further suggest that serum autoantibodies against the human M(2) muscarinic acetylcholine receptors may participate in the pathophysiological processes in patients with heart failure.