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Background: Studying the physiological growth status of Pinus yunnanensis Franch and Pinus elliottii Engelm. seedlings under different karst fissure thicknesses and rainfall distributions is of great significance for the management, vegetation restoration, and tree species selection in karst rocky desertification areas. In this study, we used a two-factor block experiment and set different rainfall durations, namely reduced rainfall duration (I3d), natural rainfall duration (I6d), and extended rainfall duration (I9d); Different karst small habitats, i.e., stone-free soil (S0), less stone and more soil (S1/4), and half stone and half soil (S1/2), are simulated at these three levels. Analyze the changes in physiological growth and photosynthetic characteristics in two coniferous seedlings under different treatments with different karst thicknesses. Results: The results showed that with the increase of karst thickness, the growth volumes of height and diameter of P. yunnanensis seedlings, the biomass of various organs, and the accumulation of K+, Ca2+, Na+, and Mg2+ showed a significant change pattern of first increasing and then decreasing (P < 0.05); P. elliottii seedlings show a gradually decreasing trend (except for Ca2+). The biomass accumulation of each organ in two coniferous seedlings showed that leaves > stems > roots. The K+, Ca2+, and Mg2+ content in various organs of P. yunnanensis seedlings showed that leaves > roots > stems, while Na+ shows the order of roots > leaves > stems. The accumulation of mineral elements in various organs of P. elliottii seedlings is manifested as roots > stems > leaves and the accumulation of mineral elements in both coniferous seedlings is manifested as Ca2+ > Mg2+ > K+ > Na+. Root length, root volume, root surface area, root diameter, SOD, POD, SP, photosynthetic pigment content, fluorescence parameters, and gas exchange parameters of P. yunnanensis seedlings gradually increase with the increase of karst thickness (except for the 9-day rainfall duration), while those of P. elliottii seedlings gradually decrease. The light saturation point of P. yunnanensis seedlings is highest under the I6dS1/2 treatment, while that of P. elliottii is highest under the I3dS0 treatment. Conclusions: In summary, prolonging rainfall duration has an inhibitory effect on the growth of two types of coniferous seedlings. Increasing karst thickness inhibits the growth of P. elliottii seedlings, and to some extent, promotes the growth and development of P. yunnanensis seedlings. I6dS1/4 and I3dS0 treatments have the best growth effects on P. yunnanensis and P. elliottii seedlings. Therefore, we give priority to P. yunnanensis as the tree species for vegetation restoration or rocky desertification management in karst areas. Our study reveals the role of limestone-filled different karst fissures in mitigating the effects of drought as "containers" for plant growth. These findings help us understand the response of plants to drought stress and provide valuable insights for vegetation restoration in karst environments affected by global climate change. Therefore, further experiments with various karst fissure sizes are necessary to test the universality of the reactions of various plants under different karst fissures. [ABSTRACT FROM AUTHOR]

Global climate change has led to a shift in rainfall patterns. And as water is an essential ingredient for plant photosynthesis, shifts in rainfall patterns will inevitably affect plant growth. This study was conducted in Kunming, southwest China. In this study, the response of leaf traits and photosynthetic fluorescence properties of Fraxinus malacophylla seedlings to rainfall patterns during the dry and rainy seasons was investigated using a natural rainfall interval of 5 days (T) and an extended rainfall interval of 10 days (T+) as rainfall interval treatments and a monthly average rainfall as a control (W), with the corresponding rainfall treatments of a 40% increase in rainfall (W+) and a 40% decrease in rainfall (W−). The results showed that Pn, Gs, and Tr basically all tended to increase and then decrease with increasing rainfall in the dry season and generally reached the highest under the W treatment; Pn, Gs, Ci, and Tr mostly remained high at 5 days relative to 10 days; PI was overall higher under the W treatment throughout the dry season. Extending the rainfall interval at the beginning of the rainy season significantly reduced Fm; throughout the rainy season, Gs, Ci, and Tr basically showed a decreasing trend with increasing rainfall, reaching the highest under the W‐treatment and mostly higher at 5 days than at 10 days. These results suggest that natural rainfall intervals and natural rainfall amounts are more favorable to the growth of Fraxinus malacophylla seedlings in the dry season; reduced rainfall and multiple rainfalls in the rainy season tend to promote photosynthesis in Fraxinus malacophylla. This study reflects the different survival strategies of Fraxinus malacophylla under different rainfall patterns, as well as provides a theoretical basis for understanding how Fraxinus malacophylla can grow better under rainfall variability and for future management. [ABSTRACT FROM AUTHOR]

Using a longitudinal sample of young Chinese students (fall and spring in grades 1 and 2: times 1-4, respectively) and growth curve analysis, this study examined whether the initial status and growth rates of compounding awareness from time 1 to time 4 uniquely contribute to reading comprehension at time 4 and whether word-reading efficiency at time 4 mediates the association between initial status and growth in compounding awareness and reading comprehension at time 4. The results indicated that initial status and growth rates of compounding awareness made a significant direct contribution to reading comprehension at the end of second grade after controlling for IQ, phonological awareness, and vocabulary knowledge. The relationship between initial status and growth rates of compounding awareness and reading comprehension were fully mediated by word-reading efficiency. The findings underscore the importance of growth in compounding awareness for reading comprehension and add to the literature about the nature of the morphological awareness and reading comprehension relationship in Chinese.

Hepatopulmonary syndrome (HPS) increases the mortality of patients who suffered from liver cirrhosis, especially patients plagued by severe hypoxemia. Gene polymorphisms are reported to be related to the risk of HPS in cirrhotic patients. Thus, our study aims to elucidate the correlation between MMP-2 and MMP-9 gene polymorphisms and HPS in cirrhotic patients. A total of 152 cirrhotic patients suffering from HPS as well as another 152 cirrhotic patients without HPS were recruited. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed for MMP-2 and MMP-9 gene polymorphisms and logistic regression analysis for the relationship between clinicopathological features and HPS occurrence in cirrhotic patients. There were significant differences in genotype and allele frequency of MMP-2 rs243865 and MMP-9 rs3918242 polymorphisms between the HPS and control groups. CC/CT genotype and C allele of MMP-2 rs243865 polymorphism as well as CC/TT genotype and T allele of MMP-9 rs3918242 polymorphism increased the risk of HPS in cirrhotic patients. Genotypes of rs243865 and rs3918242 polymorphisms had remarkable correlations with spider nevi, clubbed fingers (toes), transaminase elevation, portal vein width, esophageal varices, Child-Pugh classification and partial pressure of arterial oxygen (PaO2). Logistic regression analysis showed that rs243865 and rs3918242 polymorphisms, spider nevi, clubbed fingers (toes), esophageal varices, and Child-Pugh classification were closely associated with the occurrence of HPS in cirrhotic patients. Our findings demonstrate that MMP-2 rs243865 polymorphism and MMP-9 rs3918242 polymorphism can increase the risk of HPS occurrence in cirrhotic patients, which provides a potential target for prevention of HPS in cirrhotic patients. Keywords: Matrix metalloproteinase-2, Matrix metalloproteinase-9, Gene polymorphism, Hepatopulmonary syndrome, Cirrhosis

Abstract Fifteen known amaryllidaceae alkaloids were isolated from the bulbs of Lycoris radiata. Some of the compounds and lycoricidine derivatives had been screened for the activities against tobacco mosaic virus (TMV) by the conventional half-leaf method. Lycoricidine derivatives were also carried out the assay of effect on systemic infection of TMV by western-blot and RT-PCR analysis. The tested compounds showed moderate inactivation effect, whereas the lycoricidine derivatives showed good protective effect. The protective inhibitory activity of compounds L1 (N-methyl-2,3,4-trimethoxylycoricidine) (60.8%) and L3 (N-methyl-2-methoxy-3,4-acetonidelycoricidine) (62.0%) was almost similar to the positive control, Ningnanmycin (66.4%). RT-PCR and Western-blot analysis displayed that compounds L1, L3, L5 (N-allyl-2,3,4-triallyloxylycoricidine) exhibited antiviral activity, which was evidenced by reducing TMV-CP gene replication and TMV-CP protein expression. Additionally, defensive enzyme activities confirmed that compound L1 could increase the activity of PAL, POD, SOD to improve disease resistance of tobacco. Graphical Abstract

Two new corticioid fungal species, Phanerochaete pruinosa and P. rhizomorpha spp. nov. are proposed based on a combination of morphological features and molecular evidence. Phanerochaete pruinosa is characterized by the resupinate basidiomata with the pruinose hymenial surface, a monomitic hyphal system with simple-septate generative hyphae and subcylindrical basidiospores measuring as 3.5–6.7 × 1.5–2.7 µm. Phanerochaete rhizomorpha is characterized by having a smooth hymenophore covered by orange hymenial surface, the presence of rhizomorphs, subulate cystidia, and narrower ellipsoid to ellipsoid basidiospores. Sequences of ITS+nLSU nrRNA gene regions of the studied specimens were generated and phylogenetic analyses were performed with maximum likelihood, maximum parsimony, and Bayesian inference methods. These phylogenetic analyses showed that two new species clustered into genus Phanerochaete, in which P. pruinosa was sister to P. yunnanensis with high supports (100% BS, 100% BT, 1.00 BPP); morphologically differing by a pale orange to greyish orange and densely cracked hymenial surface. Another species P. rhizomorpha was closely grouped with P. citrinosanguinea with lower supports; morphologically having yellow to reddish yellow hymenial surface, and smaller cystidia measuring as 31–48 × 2.3–4.8 µm.

Three wood-inhabiting fungal species, Xylodon laceratus, X. montanus, and X. tropicus spp. nov., were collected from southern China, here proposed as new taxa based on a combination of morphological features and molecular evidence. Xylodon laceratus is characterized by the resupinate basidiomata with grandinioid hymenophore having cracked hymenial surface, and ellipsoid basidiospores; X. montanus is characterized by the annual basidiomata having the hard, brittle hymenophore with cream hymenial surface, and ellipsoid to broadly ellipsoid basidiospores (3.9–5.3 × 3.2–4.3 µm); and X. tropicus is characterized by its grandinioid hymenophore with buff to a pale brown hymenial surface and subglobose basidiospores measuring 2–4.8 × 1.6–4 µm. Sequences of ITS and nLSU rRNA markers of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony, and Bayesian inference methods. The ITS+nLSU analysis of the order Hymenochaetales indicated that the three new species clustered into the family Schizoporaceae, located in genus Xylodon; based on further analysis of ITS dataset, X. laceratus was a sister to X. heterocystidiatus; X. montanus closely grouped with X. subclavatus and X. xinpingensis with high support; while X.tropicus was retrieved as a sister to X. hastifer.

Background: Hepatocellular carcinoma (HCC) is closely associatedwith chronic liver diseases, particularly liver cirrhosis, which has an altered extracellular matrix (ECM) composition. The influence and its mechanism of the cirrhotic-ECM on the response of HCC to immune checkpoint inhibitor (ICI) remains less clarified. Methods: In silico, proteomic and pathological assessment of alteration of cirrhotic-ECM were applied in clinical cohort. Multiple pre-clinical models with ECM manipulation were used to evaluate cirrhotic-ECM's effect on ICI treatment. In silico, flow cytometry and IHC were applied to explore how cirrhotic-ECM affect HCC microenvironment. In vitro and in vivo experiments were carried out to identify the mechanism of how cirrhotic-ECM undermined ICI treatment. Results: We defined "a pro-tumor cirrhotic-ECM" which was featured as the up-regulation of collagen type 1 (Col1). Cirrhotic-ECM/Col1 was closely related to impaired T cell function and limited anti PD-1 (aPD-1) response of HCC patients from the TCGA pan cancer cohort and the authors' institution, as well as in multiple pre-clinical models. Mechanically, cirrhotic-ECM/Col1 orchestrated an immunosuppressive microenvironment (TME) by triggering Col1-DDR1-NFκB-CXCL8 axis, which initiated neutrophil extracellular traps (NETs) formation to shield HCC cells from attacking T cells and impede approaching T cells. Nilotinib, an inhibitor of DDR1, reversed the neutrophils/NETs dominant TME and efficiently enhanced the response of HCC to aPD-1. Conclusions: Cirrhotic-ECM modulated a NETs enriched TME in HCC, produced an immune suppressive TME and weakened ICI efficiency. Col1 receptor DDR1 could be a potential target synergically used with ICI to overcome ECM mediated ICI resistance. These provide a mechanical insight and novel strategy to overcome the ICI resistance of HCC. [ABSTRACT FROM AUTHOR]

Yunnan is located in the center of the east-Asian karst area, one of the three largest karst areas in the world. Rocky desertification is widespread in the area, which seriously restricts the sustainable development of local social economy. In this study, we summarize the research status and achievements of rocky desertification in Yunnan mainly from three aspects, rocky desertification zoning, governance model and vegetation restoration in rocky desertification areas. The results show that rocky desertification areas in Yunnan are divided into 2 large areas and 5 small ones. After years of exploration, 23 kinds in 4 categories of rocky desertification control models have been formed, and 435 kinds of plant species can be used for ecological restoration in rocky desertification areas, including 376 species of shrubs and 59 species of herbs. Finally, combined with geographical location, climate and altitude, this paper preliminarily summarizes the suitable restoration vegetation, and points out the shortcomings in the studies on the control of rocky desertification, so as to provide an important theoretical reference for the subsequent research on the restoration and control of rocky desertification vegetation. [ABSTRACT FROM AUTHOR]

To study non-structural carbohydrate characteristics and nutrient utilization strategies of Pinus yunnanensis under continuous drought conditions, 2-year-old seedlings were planted in pots with appropriate water, light and moderate and severe drought treatments [(80 ± 5), (65 ± 5), (50 ± 5), and (35 ± 5)% of field water-holding capacity]. Non-structural carbohydrates, carbon (C), nitrogen (N), and phosphorus (P) concentrations were measured in each plant component. The results show that: (1) With increasing drought, non-structural carbohydrates gradually increased in leaves, stems, and coarse roots, while gradually decreased in fine roots; (2) C concentrations of all were relatively stable under different stress levels. Phosphorous utilization of each component increased under light and moderate drought conditions, while N and P utilization efficiency of each plant component decreased under severe drought. Growth was mainly restricted by N, first decreasing and then increasing with increased drought; (3) There was a correlation between the levels of non-structural carbohydrates and C, N, and P in each component. Changes in N concentration affected the interconversion between soluble sugar and starch, which play a regulatory role in the fluctuation of the concentration of non-structural carbohydrates; and, (4) Plasticity analysis showed that P. yunnanensis seedlings responded to drought mainly by altering starch concentration, the ratio of soluble sugar to starch in leaves and stems, and further by altering N and P utilization efficiencies. Overall, these results suggest that the physiological activities of all organs of P. yunnanensis seedlings are restricted under drought and that trade-offs exist between different physiological indicators and organs. Our findings are helpful in understanding non-structural carbohydrate and nutrient adaptation mechanisms under drought in P. yunnanensis seedlings. [ABSTRACT FROM AUTHOR]