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1.
Plant Divers ; 46(4): 530-536, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39280971

RESUMO

Forests, the largest terrestrial carbon sinks, play an important role in carbon sequestration and climate change mitigation. Although forest attributes and environmental factors have been shown to impact aboveground biomass, their influence on biomass stocks in species-rich forests in southern China, a biodiversity hotspot, has rarely been investigated. In this study, we characterized the effects of environmental factors, forest structure, and species diversity on aboveground biomass stocks of 30 plots (1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi, China. Our results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other regions. Furthermore, we found that aboveground biomass was positively correlated with stand age, mean annual precipitation, elevation, structural attributes and species richness, although not with species evenness. When we compared stands with the same basal area, we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast height. These findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in China. Notably, many natural forests in southern China are not fully stocked. Therefore, their continued growth will increase their carbon storage over time.

2.
New Phytol ; 243(3): 881-893, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38840520

RESUMO

Differences in demographic and environmental niches facilitate plant species coexistence in tropical forests. However, the adaptations that enable species to achieve higher demographic rates (e.g. growth or survival) or occupy unique environmental niches (e.g. waterlogged conditions) remain poorly understood. Anatomical traits may better predict plant environmental and demographic strategies because they are direct measurements of structures involved in these adaptations. We collected 18 leaf and twig traits from 29 tree species in a tropical freshwater swamp forest in Singapore. We estimated demographic parameters of the 29 species from growth and survival models, and degree of association toward swamp habitats. We examined pairwise trait-trait, trait-demography and trait-environment links while controlling for phylogeny. Leaf and twig anatomical traits were better predictors of all demographic parameters than other commonly measured leaf and wood traits. Plants with wider vessels had faster growth rates but lower survival rates. Leaf and spongy mesophyll thickness predicted swamp association. These findings demonstrate the utility of anatomical traits as indicators of plant hydraulic strategies and their links to growth-mortality trade-offs and waterlogging stress tolerance that underlie species coexistence mechanisms in tropical forest trees.


Assuntos
Adaptação Fisiológica , Florestas , Folhas de Planta , Árvores , Clima Tropical , Áreas Alagadas , Folhas de Planta/fisiologia , Folhas de Planta/anatomia & histologia , Árvores/fisiologia , Característica Quantitativa Herdável , Água Doce , Ecossistema , Especificidade da Espécie
3.
Plant Divers ; 46(3): 395-405, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38798723

RESUMO

Stomatal regulation is critical for mangroves to survive in the hyper-saline intertidal zone where water stress is severe and water availability is highly fluctuant. However, very little is known about the stomatal sensitivity to vapour pressure deficit (VPD) in mangroves, and its co-ordination with stomatal morphology and leaf hydraulic traits. We measured the stomatal response to a step increase in VPD in situ, stomatal anatomy, leaf hydraulic vulnerability and pressure-volume traits in nine true mangrove species of five families and collected the data of genome size. We aimed to answer two questions: (1) Does stomatal morphology influence stomatal dynamics in response to a high VPD in mangroves? with a consideration of possible influence of genome size on stomatal morphology; and (2) do leaf hydraulic traits influence stomatal sensitivity to VPD in mangroves? We found that the stomata of mangrove plants were highly sensitive to a step rise in VPD and the stomatal responses were directly affected by stomatal anatomy and hydraulic traits. Smaller, denser stomata was correlated with faster stomatal closure at high VPD across the species of Rhizophoraceae, and stomata size negatively and vein density positively correlated with genome size. Less negative leaf osmotic pressure at the full turgor (πo) was related to higher operating steady-state stomatal conductance (gs); and a higher leaf capacitance (Cleaf) and more embolism resistant leaf xylem were associated with slower stomatal responses to an increase in VPD. In addition, stomatal responsiveness to VPD was indirectly affected by leaf morphological traits, which were affected by site salinity and consequently leaf water status. Our results demonstrate that mangroves display a unique relationship between genome size, stomatal size and vein packing, and that stomatal responsiveness to VPD is regulated by leaf hydraulic traits and stomatal morphology. Our work provides a quantitative framework to better understand of stomatal regulation in mangroves in an environment with high salinity and dynamic water availability.

5.
Glob Chang Biol ; 30(4): e17274, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38605677

RESUMO

Climate change and other anthropogenic disturbances are increasing liana abundance and biomass in many tropical and subtropical forests. While the effects of living lianas on species diversity, ecosystem carbon, and nutrient dynamics are receiving increasing attention, the role of dead lianas in forest ecosystems has been little studied and is poorly understood. Trees and lianas coexist as the major woody components of forests worldwide, but they have very different ecological strategies, with lianas relying on trees for mechanical support. Consequently, trees and lianas have evolved highly divergent stem, leaf, and root traits. Here we show that this trait divergence is likely to persist after death, into the afterlives of these organs, leading to divergent effects on forest biogeochemistry. We introduce a conceptual framework combining horizontal, vertical, and time dimensions for the effects of liana proliferation and liana tissue decomposition on ecosystem carbon and nutrient cycling. We propose a series of empirical studies comparing traits between lianas and trees to answer questions concerning the influence of trait afterlives on the decomposability of liana and tree organs. Such studies will increase our understanding of the contribution of lianas to terrestrial biogeochemical cycling, and help predict the effects of their increasing abundance.


Assuntos
Ecossistema , Clima Tropical , Florestas , Árvores , Carbono
6.
Tree Physiol ; 44(3)2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38366388

RESUMO

Low temperatures largely determine the geographic limits of plant species by reducing survival and growth. Inter-specific differences in the geographic distribution of mangrove species have been associated with cold tolerance, with exclusively tropical species being highly cold-sensitive and subtropical species being relatively cold-tolerant. To identify species-specific adaptations to low temperatures, we compared the chilling stress response of two widespread Indo-West Pacific mangrove species from Rhizophoraceae with differing latitudinal range limits-Bruguiera gymnorhiza (L.) Lam. ex Savigny (subtropical range limit) and Rhizophora apiculata Blume (tropical range limit). For both species, we measured the maximum photochemical efficiency of photosystem II (Fv/Fm) as a proxy for the physiological condition of the plants and examined gene expression profiles during chilling at 15 and 5 °C. At 15 °C, B. gymnorhiza maintained a significantly higher Fv/Fm than R. apiculata. However, at 5 °C, both species displayed equivalent Fv/Fm values. Thus, species-specific differences in chilling tolerance were only found at 15 °C, and both species were sensitive to chilling at 5 °C. At 15 °C, B. gymnorhiza downregulated genes related to the light reactions of photosynthesis and upregulated a gene involved in cyclic electron flow regulation, whereas R. apiculata downregulated more RuBisCo-related genes. At 5 °C, both species repressed genes related to CO2 assimilation. The downregulation of genes related to light absorption and upregulation of genes related to cyclic electron flow regulation are photoprotective mechanisms that likely contributed to the greater photosystem II photochemical efficiency of B. gymnorhiza at 15 °C. The results of this study provide evidence that the distributional range limits and potentially the expansion rates of plant species are associated with differences in the regulation of photosynthesis and photoprotective mechanisms under low temperatures.


Assuntos
Rhizophoraceae , Rhizophoraceae/genética , Rhizophoraceae/metabolismo , Complexo de Proteína do Fotossistema II/genética , Temperatura Baixa , Fotossíntese/genética , Perfilação da Expressão Gênica
7.
Bioorg Chem ; 144: 107169, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38330722

RESUMO

Four undescribed compounds including one aromatic glucoside derivative, cordyceglycoside A (1), one new isoleucine derivative inner salt, cordycepisosalt A (2), a rare four-membered lactam, cinerealactam B (3), and one sesquiterpene derivative, cordycepsetp A (4), together with six known compounds were isolated from Cordyceps militaris. The structures including absolute configurations of these new compounds, were unambiguously elucidated by spectroscopic data analysis and single crystal X-ray diffraction. Biological evaluation of compounds 1-4 showed that 3 displays anti-renal fibrotic activities in TGF-ß1 induced NRK-52e cells. Furthermore, DARTS coupled with LC-MS/MS analysis was used to identify candidate target proteins for 3. Subsequently, C1qbp knockdown using siRNA allowed us to validate the target protein of 3.


Assuntos
Cordyceps , Cordyceps/química , Cordyceps/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Análise Espectral , Fibrose
8.
Plant Divers ; 46(1): 126-133, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38343598

RESUMO

Lipids may play an important role in preventing gas embolisms by coating nanobubbles in xylem sap. Few studies on xylem sap lipids have been reported for temperate plants, and it remain unclear whether sap lipids have adaptational significance in tropical plants. In this study, we quantify the lipid composition of xylem sap for angiosperm species from a tropical savanna (seven species) and a seasonal rainforest (five species) using mass spectrometry. We found that all twelve species studied contained lipids in their xylem sap, including galactolipids, phospholipids and triacylglycerol, with a total lipid concentration ranging from 0.09 to 0.26 nmol/L. There was no difference in lipid concentration or composition between plants from the two sites, and the lipid concentration was negatively related to species' open vessel volume. Furthermore, savanna species showed little variation in lipid composition between the dry and the rainy season. These results support the hypothesis that xylem sap lipids are derived from the cytoplasm of individual conduit cells, remain trapped inside individual conduits, and undergo few changes in composition over consecutive seasons. A xylem sap lipidomic data set, which includes 12 tropical tree species from this study and 11 temperate tree species from literature, revealed no phylogenetic signals in lipid composition for these species. This study fills a knowledge gap in the lipid content of xylem sap in tropical trees and provides additional support for their common distribution in xylem sap of woody angiosperms. It appears that xylem sap lipids have no adaptive significance.

9.
Tree Physiol ; 44(3)2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38281245

RESUMO

Tropical karst habitats are characterized by limited and patchy soil, large rocky outcrops and porous substrates, resulting in high habitat heterogeneity and soil moisture fluctuations. Xylem hydraulic efficiency and safety can determine the drought adaptation and spatial distribution of woody plants growing in karst environments. In this study, we measured sapwood-specific hydraulic conductivity (Ks), vulnerability to embolism, wood density, saturated water content, and vessel and pit anatomical characteristics in the branch stems of 12 evergreen tree species in a tropical karst seasonal rainforest in southwestern China. We aimed to characterize the effects of structural characteristics on hydraulic efficiency and safety. Our results showed that there was no significant correlation between Ks and hydraulic safety across the tropical karst woody species. Ks was correlated with hydraulic vessel diameter (r = 0.80, P < 0.05) and vessel density (r = -0.60, P < 0.05), while the stem water potential at 50 and 88% loss of hydraulic conductivity (P50 and P88) were both significantly correlated with wood density (P < 0.05) and saturated water content (P = 0.052 and P < 0.05, respectively). High stem water storage capacity was associated with low cavitation resistance possibly because of its buffering the moisture fluctuations in karst environments. However, both Ks and P50/P88 were decoupled from the anatomical traits of pit and pit membranes. This may explain the lack of tradeoff between hydraulic safety and efficiency in tropical karst evergreen tree species. Our results suggest that diverse hydraulic trait combination may facilitate species coexistence in karst environments with high spatial heterogeneity.


Assuntos
Embolia , Árvores , Água , Xilema , Secas , Solo
10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1027988

RESUMO

Objective:To analyze the detection of non-alcoholic fatty liver disease (NAFLD) and the multiple corresponding relationships of its risk factors in a middle-aged and young adult population undergoing health check-ups.Methods:This study was a cross-sectional study conducted on 15 423 individuals aged between 18 and 59 who underwent health check-ups at the Health Management Center of Henan Provincial Hospital of Traditional Chinese Medicine from January to December 2021. Relevant health examination data was collected, including basic information (age, gender, past medical history, smoking and alcohol consumption), physical examination, laboratory indicators such as blood lipids and blood glucose, and abdominal ultrasound results. The chi-square test was used to compare the prevalence of NAFLD among different characteristics of the population, and multiple correspondence analysis was employed for statistical analysis of related influencing factors.Results:A total of 5 859 cases of NAFLD were detected in this study, with a detection rate of 37.99%. The detection rate of NAFLD gradually increased with age ( χ2=828.841, P<0.001) and body mass index (BMI) ( χ2=1 889.809, P<0.001). The detection rates of NAFLD were higher in individuals with hypertension, diabetes, hypercholesterolemia, hypertriglyceridemia, low high-density lipoprotein cholesterolemia, high low-density lipoprotein cholesterolemia, and hyperuricemia compared to those without these conditions ( χ2 value was 1 223.673, 364.808, 444.074, 2 436.765, 1 323.736, 591.478, and 943.069, respectively, all P<0.001). Multiple correspondence analysis revealed that NAFLD was closely related to hypertension, hypertriglyceridemia, diabetes, hyperuricemia, overweight, obesity, and the age group of 45-49 years. Correspondence analysis graphs for males and females showed associations between NAFLD and hypertension, hypertriglyceridemia, hyperuricemia, overweight, and obesity. In males, NAFLD was closely related to the age group of 35-49 years, while in females, it was closely associated with the age group of 45-49 years and diabetes. Conclusions:The detection rate of non-alcoholic fatty liver disease is relatively high in middle-aged and young adult populations. Males, those who are overweight or obese, and individuals with hypertension, diabetes, hyperuricemia, or abnormal blood lipids are more susceptible to non-alcoholic fatty liver disease.

11.
Plant Divers ; 45(5): 601-610, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37936818

RESUMO

Maintaining open flowers is critical for successful pollination and depends on long-term water and carbon balance. Yet the relationship between how flower hydraulic traits are coordinated in different habitats is poorly understood. Here, we hypothesize that the coordination and trade-offs between floral hydraulics and economics traits are independent of environmental conditions. To test this hypothesis, we investigated a total of 27 flower economics and hydraulic traits in six aquatic and six terrestrial herbaceous species grown in a tropical botanical garden. We found that although there were a few significant differences, most flower hydraulics and economics traits did not differ significantly between aquatic and terrestrial herbaceous plants. Both flower mass per area and floral longevity were significantly positively correlated with the time required for drying full-hydrated flowers to 70% relative water content. Flower dry matter content was strongly and positively related to drought tolerance of the flowers as indicated by flower water potential at the turgor loss point. In addition, there was a trade-off between hydraulic efficiency and the construction cost of a flower across species. Our results show that flowers of aquatic and terrestrial plants follow the same economics spectrum pattern. These results suggest a convergent flower economics design across terrestrial and aquatic plants, providing new insights into the mechanisms by which floral organs adapt to aquatic and terrestrial habitats.

12.
Tree Physiol ; 43(12): 2109-2120, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-37672225

RESUMO

Water stored in trunk sapwood is vital for the canopy to maintain its physiological function under high transpiration demands. Little is known regarding the anatomical properties that contribute to the hydraulic capacitance of tree trunks and whether trunk capacitance is correlated with the hydraulic and gas exchange traits of canopy branches. We examined sapwood capacitance, xylem anatomical characteristics of tree trunks, embolism resistance, the minimal xylem water potential of canopy branches, leaf photosynthesis and stomatal conductance in 22 species from a tropical seasonal rainforest and savanna. The results showed that the mean trunk sapwood capacitance did not differ between the two biomes. Capacitance was closely related to the fiber lumen fraction and fiber wall reinforcement and not to the axial and ray parenchyma fractions. Additionally, it was positively correlated with the theoretical hydraulic conductivity of a trunk and the specific hydraulic conductivity of branches, and showed a trade-off with branch embolism resistance. Species with a high trunk sapwood capacitance maintained less negative canopy water potentials in the dry season, but higher leaf photosynthetic rates and stomatal conductance in the wet season. This study provides a functional link among trunk sapwood capacitance, xylem anatomy, canopy hydraulics and photosynthesis in tropical trees.


Assuntos
Embolia , Árvores , Árvores/fisiologia , Xilema/fisiologia , Folhas de Planta/fisiologia , Fotossíntese/fisiologia , Água/fisiologia
13.
Tree Physiol ; 43(8): 1307-1318, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37067918

RESUMO

Karst forests are habitats in which access to soil water can be challenging for plants. Therefore, safe and efficient xylem water transport and large internal water storage may benefit tree growth. In this study, we selected 22 tree species from a primary subtropical karst forest in southern China and measured their xylem anatomical traits, saturated water content (SWC), hydraulic conductivity (Ks) and embolism resistance (P50). Additionally, we monitored growth of diameter at breast height (DBH) in 440 individual trees of various sizes over three consecutive years. Our objective was to analyze the relationships between xylem structure, hydraulic efficiency, safety, water storage and growth of karst tree species. The results showed significant differences in structure but not in hydraulic traits between deciduous and evergreen species. Larger vessel diameter, paratracheal parenchyma and higher SWC were correlated with higher Ks. Embolism resistance was not correlated with the studied anatomical traits, and no tradeoff with Ks was observed. In small trees (5-15 cm DBH), diameter growth rate (DGR) was independent of hydraulic traits. In large trees (>15 cm DBH), higher Ks and more negative P50 accounted for higher DGR. From lower to greater embolism resistance, the size-growth relationship shifted from growth deceleration to acceleration with increasing tree size in eight of the 22 species. Our study highlights the vital contributions of xylem hydraulic efficiency and safety to growth rate and dynamics in karst tree species; therefore, we strongly recommend their integration into trait-based forest dynamic models.


Assuntos
Florestas , Árvores , Transporte Biológico , China , Água
14.
Tree Physiol ; 43(2): 234-247, 2023 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-36209451

RESUMO

The hydraulic traits of a plant species may reflect its climate adaptations. Southwest China is considered as a biodiversity hotpot of the genus Quercus (oak). However, the hydraulic adaptations of Asian oaks to their climate niches remain unclear. Ten common garden-grown oak species with distinct natural distributions in eastern Asia were used to determine their stem xylem embolism resistance (water potential at 50% loss of hydraulic conductivity, P50), stem hydraulic efficiency (vessel anatomy and sapwood specific hydraulic conductivity (Ks)) and leaf anatomical traits. We also compiled four key functional traits: wood density, hydraulic-weighted vessel diameter, Ks and P50 data for 31 oak species from previous literature. We analyzed the relationship between hydraulic traits and climatic factors over the native ranges of 41 oak species. Our results revealed that the 10 Asian oak species, which are mainly distributed in humid subtropical habitats, possessed a stem xylem with low embolism resistance and moderate hydraulic efficiency. The deciduous and evergreen species of the 10 Asian oaks differed in the stem and leaf traits related to hydraulic efficiency. Ks differed significantly between the two phenological groups (deciduous and evergreens) in the 41-oak dataset. No significant difference in P50 between the two groups was found for the 10 Asian oaks or the 41-oak dataset. The oak species that can distribute in arid habitats possessed a stem xylem with high embolism resistance. Ks negatively related to the humidity of the native range of the 10 Asian oaks, but showed no trend when assessing the entire global oak dataset. Our study suggests that stem hydraulic conductivity and embolism resistance in Quercus species are shaped by their climate niche. Our findings assist predictions of oak drought resistance with future climate changes for oak forest management.


Assuntos
Embolia , Quercus , Quercus/anatomia & histologia , Madeira , Xilema , Florestas , Folhas de Planta , Água , Árvores , Secas
15.
J Exp Bot ; 74(3): 1123-1139, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36462194

RESUMO

Most orchids have high ornamental value with long-lived flowers. However, the mechanisms by which orchids maintain floral longevity are poorly understood. Here, we hypothesized that floral longevity in Dendrobium is maintained by high resource investment and complementary water and nutrient utilization in different structural units of the perianth. To test this hypothesis, we determined which water- and nutrient-related traits are correlated with flower longevity in 23 Dendrobium species or cultivars, and examined variations of the related traits during flower development of one long-lived cultivar. We found that floral longevity was correlated with dry mass per unit area of perianths and total flower biomass, which indicates that maintaining floral longevity requires increased resource investment. During development of long-lived flowers, labella showed a high capacity for water storage and nutrient reutilization, which could partly remedy high water demand and biomass investment. Sepals and petals, in contrast, had stronger desiccation avoidance and higher metabolic activity with lower biomass investment. These findings indicate that Dendrobium flowers maintain longevity by complementary water and nutrient utilization strategies in the sepals, petals and labella, with labella consuming more water and nutrients to extend flower display, and sepals and petals using a more conservative strategy.


Assuntos
Dendrobium , Água , Água/metabolismo , Longevidade , Reprodução , Flores
16.
Sichuan Mental Health ; (6): 53-58, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-986778

RESUMO

ObjectiveTo investigate the Alzheimer-associated neurofilament protein (AD7c-NTP) in urine of middle-aged and elderly people and its correlation between common metabolites. MethodsA total of 1 150 middle-aged and elderly people who did their physical exmanination in the health examination center of the Sichuan Science City Hospital and the Third Hopital of Mianyang were recruited from March 2017 to March 2020. The level of urine AD7c-NTP were measured by enzyme-linked immunosorbent assay (ELISA), and common metabolites in blood were measured by biochemical analyzer. Based on urine AD7c-NTP level ≤1.5 ng/mL, the objects was divided into normal group (n=956) and elevated group (n=194). Thier demographic data and blood biochemical indicators were collected. ResultsThe urine AD7c-NTP level in middle-aged and elderly people was 0.60(0.30~1.20) ng/mL. The urine AD7c-NTP level was higher in women than that in men [1.04(0.40~1.30) ng/mL vs. 0.84(0.30~1.00) ng/mL, Z=4.202, P˂0.01]. And the urine AD7c-NTP level was lower in the normal group than that in the elevated group [0.50(0.30~0.90) ng/mL vs. 2.10(1.70~2.10) ng/mL, Z=22.035, P˂0.01]. The results of the univariate comparison showed that, the differences between the two groups in age (Z=6.545), fasting glucose (Z=3.506), blood uric acid (Z=2.574), urea nitrogen (Z=2.891), creatinine (Z=2.243), total bilirubin (Z=3.936), glutathione (Z=0.969), total cholesterol (t=3.956) and low density lipoprotein (Z=-5.678) were were statistically significant (P˂0.05 or 0.01). Spearman correlation analysis showed that, the urine AD7c-NTP level was positively correlated with age and the levels of urea nitrogen, glucose, total cholesterol and low density lipoprotein (r=0.177, 0.178, 0.171, 0.109, 0.149, P˂0.01), and negatively correlated with the level of total bilirubin (r=-0.172, P˂0.01). Conclusionthe urine AD7c-NTP level in middle-aged and elderly females was signifitcantly higher than in middle-aged and elderly males.The urine AD7c-NTP level of middle-aged and elderly people was positively correlated with age, urea nitrogen, glucose, total cholesterol and low density lipoprotein, and negatively correlated with total bilirubin.

17.
Acta Anatomica Sinica ; (6): 269-275, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1015216

RESUMO

[Abstract] Objective To establish an inflammation model by stimulating BV2 microglia by lipopolysaccharide, and to explore the regulation effect of ginsenoside Rg1 on inflammation by activating peroxisome proliferator activated receptor γ(PPARγ) receptor protein. Methods BV2 microglia were randomly divided into control group, model group, ginsenoside Rg1 group, rosiglitazone group and GW9662 group. The control group did not do any treatment, the model group was treated with 1 mg/ L lipopolysaccharide, and the other groups were treated with lipopolysaccharide added with 0. 4 mmol/ L ginsenoside Rg1, 10 μmol/ L rosiglitazone or 10 μmol/ L respectively. GW9662. The proliferation of BV2 microglia in each group was detected by CCK-8 method; PPAR-γ, phospho-NF-κB p65 (p-NF-κB p65), induced expression of inducible nitric oxide synthase(iNOS) and human arginase 1(ARG-1) proteins. ELISA was used to detect the inflammatory factors interleukin-1β(IL-1β), interleukin-6(IL-6), interleukin-8(IL-8) and the content of tumor necrosis factor-α (TNF-α). Results Compared with the control group, the cell proliferation rate in the model group was significantly increased, and the contents of IL-1β, IL-6, IL-8 and TNF-α increased significantly. The result of immunofluorescence and Western blotting showed that iNOS and p-NF-κB p65 increased significantly, and the positive expressions of PPARγ and ARG-1 decreased significantly(both P<0. 01). The expression level of TNF-α decreased, the positive expressions of iNOS and p-NF-κB p65 decreased significantly, and the positive expressions of PPARγ and ARG-1 increased significantly(all P<0. 01). Conclusion Ginsenoside Rg1 inhibits the inflammatory response of BV2 microglia after lipopolysaccharide stimulation, and its mechanism may be related to the regulation of PPARγ/ NF-κB pathway to promote the M2-type polarization of microglia.

18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-996582

RESUMO

@#Objective    To explore the treatment outcome of carotid endarterectomy combined with vertebral artery transposition in patients with severe stenosis to occlusion of the vertebral artery V1 segment and the ipsilateral carotid artery. Methods    From June 2017 to September 2020, patients with severe stenosis to occlusion of the vertebral artery V1 segment and the ipsilateral carotid artery treated with carotid endarterectomy combined with vertebral artery transposition in Fuwai Hospital were retrospectively analyzed. Results    Finally 12 patients were enrolled, including 10 males and 2 females with an average age of 67.8±6.0 years. Twelve patients were successfully operated and the follow-up time was 1-3 years. The stenosis degree of the V1 segment of the vertebral artery decreased from 83.5%±11.8% to 24.9%±14.3% (P<0.001). The stenosis degree of carotid artery decreased from 85.6%±11.0% to 0% (P<0.001). Postoperative follow-up showed that the symptoms of symptomatic patients before surgery improved. The 1-year and 3-year patency rates were 100.0%, and there were no peripheral nerve injury complications, perioperative deaths or strokes. Conclusion    Carotid endarterectomy combined with vertebral artery transposition can treat ipsilateral carotid artery  stenosis and vertebral artery stenosis at the same time, improve blood supply to the brain, improve patients' symptoms and has high promotion value.

19.
Ann Bot ; 131(2): 347-360, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36516425

RESUMO

BACKGROUND AND AIMS: While genome size limits the minimum sizes and maximum numbers of cells that can be packed into a given leaf volume, mature cell sizes can be substantially larger than their meristematic precursors and vary in response to abiotic conditions. Mangroves are iconic examples of how abiotic conditions can influence the evolution of plant phenotypes. METHODS: Here, we examined the coordination between genome size, leaf cell sizes, cell packing densities and leaf size in 13 mangrove species across four sites in China. Four of these species occurred at more than one site, allowing us to test the effect of climate on leaf anatomy. RESULTS: We found that genome sizes of mangroves were very small compared to other angiosperms, but, like other angiosperms, mangrove cells were always larger than the minimum size defined by genome size. Increasing mean annual temperature of a growth site led to higher packing densities of veins (Dv) and stomata (Ds) and smaller epidermal cells but had no effect on stomatal size. In contrast to other angiosperms, mangroves exhibited (1) a negative relationship between guard cell size and genome size; (2) epidermal cells that were smaller than stomata; and (3) coordination between Dv and Ds that was not mediated by epidermal cell size. Furthermore, mangrove epidermal cell sizes and packing densities covaried with leaf size. CONCLUSIONS: While mangroves exhibited coordination between veins and stomata and attained a maximum theoretical stomatal conductance similar to that of other angiosperms, the tissue-level tradeoffs underlying these similar relationships across species and environments were markedly different, perhaps indicative of the unique structural and physiological adaptations of mangroves to their stressful environments.


Assuntos
Magnoliopsida , Magnoliopsida/genética , Magnoliopsida/anatomia & histologia , Estômatos de Plantas/fisiologia , Tamanho do Genoma , Folhas de Planta/fisiologia , Tamanho Celular
20.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-1010269

RESUMO

OBJECTIVE@#To evaluate whether electroacupuncture (EA) would improve gastrointestinal function and clinical prognosis in patients with severe traumatic brain injury (TBI) complicocted by acute gastrointestinal injury (AGI).@*METHODS@#This multicenter, single-blind trial included patients with TBI and AGI admitted to 5 Chinese hospitals from September 2018 to December 2019. A total of 500 patients were randomized to the control or acupuncture groups using a random number table, 250 cases in each group. Patients in the control group received conventional treatment, including mannitol, nutritional support, epilepsy and infection prevention, and maintenance of water, electrolytes, and acid-base balance. While patients in the acupuncture group received EA intervention at bilateral Zusanli (ST 36), Shangjuxu (ST 37), Xiajuxu (ST 39), Tianshu (ST 25), and Zhongwan (RN 12) acupoints in addition to the conventional treatment, 30 min per time, twice daily, for 7 d. The primary endpoint was 28-d mortality. The secondary endpoints were serum levels of D-lactic acid (D-lac), diamine oxidase (DAO), lipopolysaccharide (LPS), motilin (MTL) and gastrin (GAS), intra-abdominal pressure (IAP), bowel sounds, abdominal circumference, AGI grade, scores of gastrointestinal failure (GIF), Glasgow Coma Scale (GCS), Acute Physiology and Chronic Health Evaluation (APACHE II), Sequential Organ Failure Assessment (SOFA), and Multiple Organ Dysfunction Syndrome (MODS), mechanical ventilation time, intense care unit (ICU) stay, and the incidence of hospital-acquired pneumonia.@*RESULTS@#The 28-d mortality in the acupuncture group was lower than that in the control group (22.80% vs. 33.20%, P<0.05). Compared with the control group, the acupuncture group at 7 d showed lower GIF, APACHE II, SOFA, MODS scores, D-lac, DAO, LPS, IAP, and abdominal circumference and higher GCS score, MTL, GAS, and bowel sound frequency (all P<0.05). In addition, the above indices showed simillar changes at 7 d compared with days 1 and 3 (all P<0.05) in the EA group.@*CONCLUSION@#Early EA can improve gastrointestinal function and clinical prognosis in patients with severe TBI complicated by AGI. (Registration No. ChiCTR2000032276).


Assuntos
Humanos , Eletroacupuntura , Lipopolissacarídeos , Método Simples-Cego , Terapia por Acupuntura , Lesões Encefálicas Traumáticas/terapia
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