ABSTRACT
Understanding the complex interactions between trees and fungi is crucial for forest ecosystem management, yet the influence of tree mycorrhizal types, species identity, and diversity on tree-tree interactions and their root-associated fungal communities remains poorly understood. Our study addresses this gap by investigating root-associated fungal communities of different arbuscular mycorrhizal (AM) and ectomycorrhizal (EcM) tree species pairs (TSPs) in a subtropical tree diversity experiment, spanning monospecific, two-species, and multi-species mixtures, utilizing Illumina sequencing of the ITS2 region. The study reveals that tree mycorrhizal type significantly impacts the alpha diversity of root-associated fungi in monospecific stands. Meanwhile, tree species identity's influence is modulated by overall tree diversity. Tree-related variables and spatial distance emerged as major drivers of variations in fungal community composition. Notably, in multi-species mixtures, compositional differences between root fungal communities of AM and EcM trees diminish, indicating a convergence of fungal communities irrespective of mycorrhizal type. Interestingly, dual mycorrhizal fungal communities were observed in these multi-species mixtures. This research underscores the pivotal role of mycorrhizal partnerships and the interplay of biotic and abiotic factors in shaping root fungal communities, particularly in varied tree diversity settings, and its implications for effective forest management and biodiversity conservation.
Subject(s)
Biodiversity , Forests , Mycobiome , Mycorrhizae , Plant Roots , Species Specificity , Trees , Mycorrhizae/physiology , Trees/microbiology , Plant Roots/microbiologyABSTRACT
Sustaining the development of rural and pastoral communities' hinges on livelihood resilience. Pastoralist household resilience relies on resource availability and decision-making abilities. Despite extensive studies on pastoralist livelihoods, a significant knowledge gap remains in understanding the nuanced adaptive capacities of diverse households, particularly amid grassland degradation. Thus, this study investigates the household-based livelihood resilience of pastoralists in China's Three-River Headwater Region, offering policy recommendations for resilient livelihoods. Using stratified random sampling, 758 pastoralist household heads underwent semi-structured interviews to collect data. Five household characteristics, encompassing age, gender, energy use, well-being perception, and multi-household grazing participation, were evaluated. Looking ot the nature of data, descriptive statistics and non-parametric tests were performed in this study to draw the valid inferences. The results revealed a positive correlation (p < 0.05) between household head age and livelihood resilience, with divergent resilience across age groups. Varied energy usage yielded distinct impacts; households employing solar or mixed energy sources exhibited heightened resilience (p < 0.05). Household well-being emerged as an invariant variable concerning resilience. Furthermore, engagement in multi-household grazing (an informal institution) significantly (p < 0.05) influenced pastoralist livelihood resilience. These insights advocate targeted support for young household heads and the adoption of clean energy. Exploring the deeper strategies and mechanisms of multi-household grazing can enhance understanding and policy integration, guiding eco-friendly progress within rustic landscapes for pastoral communities.
ABSTRACT
The importance of the rare microbial biosphere in maintaining biodiversity and ecological functions has been highlighted recently. However, the current understanding of the spatial distribution of rare microbial taxa is still limited, with only a few investigations for rare prokaryotes and virtually none for rare fungi. Here, we investigated the spatial patterns of rare and abundant fungal taxa in alpine grassland soils across 2,000 km of the Qinghai-Tibetan plateau. We found that most locally rare fungal taxa remained rare (13.07%) or were absent (82.85%) in other sites, whereas only a small proportion (4.06%) shifted between rare and abundant among sites. Although they differed in terms of diversity levels and compositions, the distance decay relationships of both the rare and the abundant fungal taxa were valid and displayed similar turnover rates. Moreover, the community assemblies of both rare and abundant fungal taxa were predominantly controlled by deterministic rather than stochastic processes. Notably, the community composition of rare rather than abundant fungal taxa associated with the plant community composition. In summary, this study advances our understanding of the biogeographic features of rare fungal taxa in alpine grasslands and highlights the concordance between plant communities and rare fungal subcommunities in soil. IMPORTANCE Our current understanding of the ecology and functions of rare microbial taxa largely relies on research conducted on prokaryotes. Despite the key ecological roles of soil fungi, little is known about the biogeographic patterns and drivers of rare and abundant fungi in soils. In this study, we investigated the spatial patterns of rare and abundant fungal taxa in Qinghai-Tibetan plateau (QTP) alpine grassland soils across 2,000 km, with a special concentration on the importance of the plant communities in shaping rare fungal taxa. We showed that rare fungal taxa generally had a biogeographic pattern that was similar to that of abundant fungal taxa in alpine grassland soils on the QTP. Furthermore, the plant community composition was strongly related to the community composition of rare taxa but not abundant taxa. In summary, this study significantly increases our biogeographic and ecological knowledge of rare fungal taxa in alpine grassland soils.
Subject(s)
Grassland , Soil , Plants , Biodiversity , Tibet , Soil MicrobiologyABSTRACT
Extensive global glacial retreats are threatening cryosphere ecosystem functioning and the associated biota in glacier-fed water systems. Understanding multi-group biodiversity distributions and compositional variation across diverse but hydrologically linked habitats under varying glacial influences will help explain the mechanisms underlying glacial community organization and ecosystem processes. However, such data are generally lacking due to the difficulty of obtaining biodiversity information across wide taxonomic ranges. Here, we used a multi-marker environmental DNA metabarcoding approach to simultaneously investigate the spatial patterns of community compositions and assembly mechanisms of four taxonomic groups (cyanobacteria, diatoms, invertebrates, and vertebrates) along the flowpaths of a tributary of Lake Nam Co on the Tibetan Plateau-from its glacier headwaters, through its downstream river and wetlands, to its estuary. We detected 869 operational taxonomic units: 119 cyanobacterial, 395 diatom, 269 invertebrate, and 86 vertebrate. Taxonomic richnesses consistently increased from upstream to downstream, and although all groups showed community similarity distance decay patterns, the trend for vertebrates was the weakest. Cyanobacteria, diatom, and invertebrate community compositions were significantly correlated with several environmental factors, while the vertebrate community was only correlated with waterway width. Variation partitioning analysis indicated that varying extents of environmental conditions and spatial factors affected community organizations for different groups. Furthermore, stochastic processes contributed prominently to the microorganisms' community assembly (Sloan's neutral model R2 = 0.77 for cyanobacteria and 0.73 for diatoms) but were less important for macroorganisms (R2 = 0.21 for invertebrates and 0.15 for vertebrates). That trend was further substantiated by modified stochasticity ratio analyses. This study provides the first holistic picture of the diverse biotic communities residing in a series of hydrologically connected glacier-influenced habitats. Our results both uncovered the distinct mechanisms that underlie the metacommunity organizations of different glacial organisms and helped comprehensively predict the ecological impacts of the world's melting glaciers.
Subject(s)
Cyanobacteria , Ecosystem , Animals , Tibet , Biodiversity , InvertebratesABSTRACT
There is limited knowledge on how the association of trees with different mycorrhizal types shapes soil microbial communities in the context of changing tree diversity levels. We used arbuscular (AM) and ectomycorrhizal (EcM) tree species as con- and heterospecific tree species pairs (TSPs), which were established in plots of three tree diversity levels including monocultures, two-species mixtures and multi-tree species mixtures in a tree diversity experiment in subtropical China. We found that the tree mycorrhizal type had a significant effect on fungal but not bacterial alpha diversity. Furthermore, only EcM but not AM TSPs fungal alpha diversity increased with tree diversity, and the differences between AM and EcM TSPs disappeared in multi-species mixtures. Tree mycorrhizal type, tree diversity and their interaction had significant effects on fungal community composition. Neither fungi nor bacteria showed any significant compositional variation in TSPs located in multi-species mixtures. Accordingly, the most influential taxa driving the tree mycorrhizal differences at low tree diversity were not significant in multi-tree species mixtures. Collectively, our results indicate that tree mycorrhizal type is an important factor determining the diversity and community composition of soil microbes, and higher tree diversity levels promote convergence of the soil microbial communities. SIGNIFICANCE STATEMENT: More than 90% of terrestrial plants have symbiotic associations with mycorrhizal fungi which could influence the coexisting microbiota. Systematic understanding of the individual and interactive effects of tree mycorrhizal type and tree species diversity on the soil microbiota is crucial for the mechanistic comprehension of the role of microbes in forest soil ecological processes. Our tree species pair (TSP) concept coupled with random sampling within and across the plots, allowed us the unbiased assessment of tree mycorrhizal type and tree diversity effects on the tree-tree interaction zone soil microbiota. Unlike in monocultures and two-species mixtures, we identified species-rich and converging fungal and bacterial communities in multi-tree species mixtures. Consequently, we recommend planting species-rich mixtures of EcM and AM trees, for afforestation and reforestation regimes. Specifically, our findings highlight the significance of tree mycorrhizal type in studying 'tree diversity - microbial diversity - ecosystem function' relationships.
Subject(s)
Microbiota , Mycorrhizae , Bacteria/genetics , Forests , Plants , Soil , Soil Microbiology , Trees/microbiologyABSTRACT
Microtopography affects hydrological processes and forms different microhabitats. Our previous study uncovered that riparian zone microtopography created various microhabitats with different soil environments and runoff-infiltration patterns. However, how riparian microtopography and microtopography within the water area (waterfall and tributary) affects downstream water quality remains unclear. Therefore, water samples were taken almost monthly in both the main stream and the tributary, before and after waterfalls, and near the bottom of three microtopographic types from June 2016 to March 2017. Compared with the dry season, the fact that water quality worsened in the wet season and that there were positive correlations for nitrate (NO3-) between water and the corresponding soil samples suggested that the riparian-soil environment affected the adjacent water quality mainly in the wet season. Nevertheless, riparian microtopography did not influence water quality downstream because of the low rainfall frequency and the weak leaching process due to plant interception. In the wet season, both the tributary and the waterfall increased the dissolved oxygen in the water body and, therefore, lowered the risk of eutrophication. The tributary has two pathways for improving the water quality, by increased disturbance and flow velocity, while the waterfall only has the former. However, such effects were not significant in the dry season. We conclude that the application of microtopographic modification is useful in maintaining urban wetland water quality in wet seasons.
Subject(s)
Conservation of Natural Resources/methods , Wetlands , Oxygen , Seasons , Water QualityABSTRACT
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ABSTRACT
Hypoxic injury of cardiac microvascular endothelial cells (CMECs) is an important pathophysiological event in myocardial infarction, whereas, the underlying mechanism is still poorly understood. Autophagy, a highly conserved process of cellular degradation, is required for normal cardiac function and also has been implicated in various cardiovascular diseases. Here we investigated the potential role of autophagy in CMEC dysfunction under hypoxia. CMECs were isolated from SD rats. Hypoxia (6-24h, 1% O2) induced autophagy in CMECs as evidenced by formation of punctate LC3, increased conversion of LC3-I to LC3-II and increased p62 degradation. Importantly, hypoxia-induced apoptosis in CMECs was attenuated by 3-Methyladenine (5mM), an autophagy inhibitor, and aggravated by rapamycin (1.0 µg/L), an autophagy inducer. Meanwhile, hypoxia increased the nuclear localization of FoxO3α, accompanying with the decreased phosphorylation of FoxO3α and Akt. FoxO3α silencing decreased hypoxia-induced autophagy and the resultant apoptosis. Furthermore, treatment with 3-Methyladenine (10mg/kg/day) improved the endothelial-dependent diastolic function of coronary artery in rats with myocardial infarction. These results indicated that hypoxia-induced autophagy formation in CMECs is mediated by FoxO3α and contributes to hypoxic injury of hearts.
Subject(s)
Forkhead Transcription Factors/metabolism , Myocardium/cytology , Myocardium/metabolism , Adenine/analogs & derivatives , Adenine/pharmacology , Animals , Apoptosis/physiology , Autophagy/drug effects , Autophagy/physiology , Cell Hypoxia/physiology , Cells, Cultured , Endothelial Cells/cytology , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Forkhead Box Protein O3 , Forkhead Transcription Factors/antagonists & inhibitors , Forkhead Transcription Factors/genetics , Gene Silencing , Male , Microvessels/cytology , Microvessels/metabolism , Myocardial Infarction/drug therapy , Myocardial Infarction/pathology , Myocardial Infarction/physiopathology , RNA, Small Interfering/genetics , Rats , Rats, Sprague-Dawley , Sirolimus/pharmacologyABSTRACT
OBJECTIVE: Examine the effect of electrical stimulation of nucleus tractus solitaries (NTS) on cardiac-somatic motor reflex (CMR) that induced by intrapericardial administration of capsaicin to clarify the spinal cord mechanism of NTS involved in cardiac nociception in rat. METHODS: SD rats were randomly divided into electrical stimulation, control, yohimbine and naloxone group and treated with elecetrical stimulation NTS alone, or with intrathecal injection of vehicle, saline, norepinephrine a2 receptors antagonist (yohimbine), opioid receptor antagonist (naloxone) respectively. RESULTS: Electrical stimulation of NTS (10, 20, 50 MA), the CMR response deceased in an intensity-dependent manner (P<0.05); intrathecal injection of vehicle, saline had no effect on the inhibition effect of electrical stimulation (P>0.05); intrathecal injection of yohimbine (20 microg, 50 microg) or naloxone (50 microg, 100 microg), reversed the inhibition effect of electrical stimulation (P<0.05); intrathecal injection of low dose of naloxone, the inhibition effect of electrical stimulation was potentiated. CONCLUSION: Electrical stimulation of NTS has inhibition effect on cardiac nociception, norepinephrine alpha2 receptors and opioid receptor in spinal cord involved in this descending inhibition, low dose of naloxone has synergetic effect with descending inhibition.
Subject(s)
Electric Stimulation , Heart/physiology , Nociception/physiology , Solitary Nucleus/physiology , Spinal Cord/physiology , Animals , Capsaicin , Injections, Spinal , Naloxone/pharmacology , Rats , Rats, Sprague-Dawley , Reflex , Yohimbine/pharmacologyABSTRACT
Differences in progress across sustainable development goals (SDGs) are widespread globally; meanwhile, the rising call for prioritizing specific SDGs may exacerbate such gaps. Nevertheless, how these progress differences would influence global sustainable development has been long neglected. Here, we present the first quantitative assessment of SDGs' progress differences globally by adopting the SDGs progress evenness index. Our results highlight that the uneven progress across SDGs has been a hindrance to sustainable development because (1) it is strongly associated with many public health risks (e.g., air pollution), social inequalities (e.g., gender inequality, modern slavery, wealth gap), and a reduction in life expectancy; (2) it is also associated with deforestation and habitat loss in terrestrial and marine ecosystems, increasing the challenges related to biodiversity conservation; (3) most countries with low average SDGs performance show lower progress evenness, which further hinders their fulfillment of SDGs; and (4) many countries with high average SDGs performance also showcase stagnation or even retrogression in progress evenness, which is partly ascribed to the antagonism between climate actions and other goals. These findings highlight that while setting SDGs priorities may be more realistic under the constraints of multiple global stressors, caution must be exercised to avoid new problems from intensifying uneven progress across goals. Moreover, our study reveals that the urgent needs regarding SDGs of different regions seem complementary, emphasizing that regional collaborations (e.g., demand-oriented carbon trading between SDGs poorly performed and well-performed countries) may promote sustainable development achievements at the global scale.
ABSTRACT
The current study examined the role of the lateral reticular nucleus (LRN) in modulating the cardiosomatic reflex (CSR) induced by intrapericardial capsaicin in the anesthetized rat. Intrapericardial capsaicin was administered, and the CSR was monitored via electromyogram responses of the dorsal spinotrapezius muscle. Electrical stimulation of the LRN (10, 20 and 30 µA) depressed the CSR induced by intrapericardial capsaicin in an intensity-dependent manner. Microinjection of glutamate (4, 10, 20 and 40 nmol, in 0.2 µL) into the LRN replicated the effects of electrical stimulation. Furthermore, bilateral transections of the dorsolateral funiculus (DLF) decreased the LRN electrical stimulation-induced inhibition of the electromyogram responses. Intrathecal administration of the α2 -adrenergic receptor antagonist yohimbine or the serotonergic receptor antagonist methysergide significantly attenuated the LRN electrical stimulation-induced inhibition of the electromyogram responses. However, intrathecal application of the opioid receptor antagonist naloxone had no effect on the LRN electrical stimulation-induced inhibition. These results suggest that the LRN-DLF-spinal cord pathway is involved in descending inhibition of the CSR, and spinal α2 -adrenergic and serotonergic receptors participate in this descending inhibition.
Subject(s)
Capsaicin/pharmacology , Heart/physiology , Medulla Oblongata/physiology , Muscle, Skeletal/physiology , Reflex/physiology , Sensory System Agents/pharmacology , Animals , Electric Stimulation , Electromyography , Glutamic Acid/pharmacology , Heart/innervation , Male , Muscle Contraction , Muscle, Skeletal/innervation , Naloxone/pharmacology , Neural Pathways/physiology , Rats , Rats, Sprague-Dawley , Reflex/drug effectsABSTRACT
BACKGROUND: Researches have shown that soluble epoxide hydrolase inhibitors (sEHi) can protect against the development of atherosclerosis. Simultaneously, emerging evidences have implicated the association between fatty acid synthase (FAS) and acute coronary syndrome (ACS). We tested the hypothesis that sEHi could reduce the occurrence of ACS by regulating FAS. METHODS: Hospitalized ACS patients were selected as the ACS group (n = 65) while healthy normal subjects as the control group (n = 65). The blood levels of lipoproteins, fasting glucose, myocardial enzyme and high-sensitivity C-reactive protein (hs-CRP) were measured within 24 hours after admission. The peripheral blood mononuclear cells (PBMCs) were isolated and cultured. Trans-4-[4-(3-Adamantan-1-ylureido)cyclohexyloxy] benzoic acid (t-AUCB), a kind of sEHi, was then added to cells in various concentrations (0, 10, 50, 100 µmol/L). The expression of FAS, interleukin-6 (IL-6) mRNA and protein was detected by real-time PCR or Western blot, respectively. RESULTS: (1) Compared with the control group, the serum concentration of hs-CRP in the ACS group was increased (P<0.05). The expression of FAS, IL-6 mRNA and protein were significantly increased in PBMCs from the ACS group (all P<0.05). Moreover, the levels of FAS and IL-6 mRNA were positively correlated with the serum concentration of hs-CRP (r = 0.685, P<0.01; r = 0.715, P<0.01) respectively. (2) The expression of FAS, IL-6 mRNA and protein in PBMCs from the ACS group were dose-dependently inhibited by sEHi (all P<0.05). CONCLUSIONS: sEH inhibition regulated FAS and inhibited inflammation in cultured PBMCs from ACS patients, a mechanism that might prevent rupture of atherosclerotic lesions and protect against development of ACS.
Subject(s)
Acute Coronary Syndrome/metabolism , Benzoates/pharmacology , Enzyme Inhibitors/pharmacology , Fatty Acid Synthase, Type I/antagonists & inhibitors , Gene Expression/drug effects , Leukocytes, Mononuclear/drug effects , Urea/analogs & derivatives , Acute Coronary Syndrome/pathology , Aged , C-Reactive Protein/metabolism , Case-Control Studies , Cells, Cultured , Dose-Response Relationship, Drug , Epoxide Hydrolases/antagonists & inhibitors , Epoxide Hydrolases/genetics , Epoxide Hydrolases/metabolism , Fatty Acid Synthase, Type I/genetics , Fatty Acid Synthase, Type I/metabolism , Female , Humans , Interleukin-6/genetics , Interleukin-6/metabolism , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/pathology , Male , Middle Aged , RNA, Messenger/genetics , RNA, Messenger/metabolism , Solubility , Urea/pharmacologyABSTRACT
OBJECTIVE: To determine the effects of NMDA and NK1 receptor agonist and antagonist on the EMG and the synaptic mechanism of nociceptive information transmissions in the spinal cords. METHODS: Male SD rats were randomly divided into seven groups, with intrathecal injection of the following chemicals respectively: control group (10 microL saline), NMDA group (0.147 microg/10 pL NMDA), MK801 group (6.8 microg/10 microL MK801), MK801+NMDA group (6.8 microg/10 pL MK801+0. 147 microg/10 pL NMDA), Sar-SP group (1.4 pg/10 microL Sar-SP), CP-96345 group (5 microg/10 pL CP-96345), and CP-96345+Sar-SP group (1.4 micro/10 microL Sar-SP+5 microg/10 microL CP-96345). A cardiac pain model in rats through intrapericardial injection of capsaicin was established. Intrapericardial injection of capsaicin was given to the rats 10 min after intrathecal injection of the tested chemicals. The spinotrapezius electromyography (EMG) activities as an index of cardiac-somatic motor reflex were recorded simultaneously. RESULTS: Compared with the pre-test controls (100%), saline did not make a significant change to the capsaicin-evoked EMG response (96. 9% +/- 12. 5%, P>0. 05); NMDA agonist increased the capsaicin-evoked EMG response (185. 2% +/- 24. 4%) significantly (P<0. 05); neither MK801 nor a combined administration of MK801 and NMDA made a significant change to the capsaicin-evoked EMG response (106. 6% +/- 10. 2%, P> 0.05); Sar-SP increased the capsaicin-evoked EMG response (145. 6% 10. 1%) significantly (P<0. 05); whereas neither CP-96345 nor a combined administration of CP-96345 and Sar-SP made a significant change to the capsaicin-evoked EMG response (102. 2% +/- 8. 4%, P>0.05). CONCLUSION: NMDA and NK1 receptors may have participated in the transmissions of cardiac nociception information in the spinal cords of rats.
Subject(s)
Heart/innervation , Nociceptors/physiology , Receptors, N-Methyl-D-Aspartate/physiology , Receptors, Neurokinin-1/physiology , Spinal Cord/physiology , Animals , Biphenyl Compounds/administration & dosage , Capsaicin/administration & dosage , Chest Pain/physiopathology , Dizocilpine Maleate/administration & dosage , Male , Rats , Rats, Sprague-Dawley , Receptors, N-Methyl-D-Aspartate/agonists , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Receptors, Neurokinin-1/agonists , Substance P/antagonists & inhibitors , Synaptic Transmission/physiologyABSTRACT
BACKGROUND: This article describes a systematic review evaluating the effectiveness of training on the humanistic care abilities of nurses. METHOD: The literature search was conducted in electronic databases to identify studies that evaluated the effect of training on the humanistic care abilities of nurses. Study selection was based on precise eligibility criteria. After the systematic review, a meta-analysis of standardized mean differences (SMDs) between posttraining and pretraining humanistic care scale scores was performed to evaluate the effect of training. RESULTS: A total of 11 studies were included (624 nurse participants; 97% women; weighted average age = 38.4 years; 95% confidence interval (CI) [31.5, 45.4]). Training schedules varied and ranged from a full-day workshop to brief weekly sessions for up to 2 months. The training framework involved compassion and empathy communication in most of the included studies. Training improved the humanistic care scale scores of the participants (SMD = 1.171; 95% CI [0.626, 1.716]; p < .0001), whereas no significant change was seen in the scores of control subjects (SMD = 0.588; 95% CI [-0.536, 1.713]; p = .305). The effect of training was observable for up to 1 year, although few studies carried out follow-up evaluations. CONCLUSION: Training has the potential to improve the humanistic care abilities of nurses. [J Contin Educ Nurs. 2023;54(9):430-436.].
Subject(s)
Communication , Nurses , Humans , Female , Adult , Male , EmpathyABSTRACT
Soil microbial communities play crucial roles in the earth's biogeochemical cycles. Yet, their genomic potential for nutrient cycling in association with tree mycorrhizal type and tree-tree interactions remained unclear, especially in diverse tree communities. Here, we studied the genomic potential of soil fungi and bacteria with arbuscular (AM) and ectomycorrhizal (EcM) conspecific tree species pairs (TSPs) at three tree diversity levels in a subtropical tree diversity experiment (BEF-China). The soil fungi and bacteria of the TSPs' interaction zone were characterized by amplicon sequencing, and their subcommunities were determined using a microbial interkingdom co-occurrence network approach. Their potential genomic functions were predicted with regard to the three major nutrients carbon (C), nitrogen (N), and phosphorus (P) and their combinations. We found the microbial subcommunities that were significantly responding to different soil characteristics. The tree mycorrhizal type significantly influenced the functional composition of these co-occurring subcommunities in monospecific stands and two-tree-species mixtures but not in mixtures with more than three tree species (here multi-tree-species mixtures). Differentiation of subcommunities was driven by differentially abundant taxa producing different sets of nutrient cycling enzymes across the tree diversity levels, predominantly enzymes of the P (n = 11 and 16) cycles, followed by the N (n = 9) and C (n = 9) cycles, in monospecific stands and two-tree-species mixtures, respectively. Fungi of the Agaricomycetes, Sordariomycetes, Eurotiomycetes, and Leotiomycetes and bacteria of the Verrucomicrobia, Acidobacteria, Alphaproteobacteria, and Actinobacteria were the major differential contributors (48% to 62%) to the nutrient cycling functional abundances of soil microbial communities across tree diversity levels. Our study demonstrated the versatility and significance of microbial subcommunities in different soil nutrient cycling processes of forest ecosystems. IMPORTANCE Loss of multifunctional microbial communities can negatively affect ecosystem services, especially forest soil nutrient cycling. Therefore, exploration of the genomic potential of soil microbial communities, particularly their constituting subcommunities and taxa for nutrient cycling, is vital to get an in-depth mechanistic understanding for better management of forest soil ecosystems. This study revealed soil microbes with rich nutrient cycling potential, organized in subcommunities that are functionally resilient and abundant. Such microbial communities mainly found in multi-tree-species mixtures associated with different mycorrhizal partners can foster soil microbiome stability. A stable and functionally rich soil microbiome is involved in the cycling of nutrients, such as carbon, nitrogen, and phosphorus, and their combinations could have positive effects on ecosystem functioning, including increased forest productivity. The new findings could be highly relevant for afforestation and reforestation regimes, notably in the face of growing deforestation and global warming scenarios.
Subject(s)
Microbiota , Mycorrhizae , Mycorrhizae/genetics , Trees/microbiology , Soil/chemistry , Soil Microbiology , Bacteria/genetics , Phosphorus , Nitrogen , CarbonABSTRACT
Structural information of grassland changes on the Tibetan Plateau is essential for understanding alterations in critical ecosystem functioning and their underlying drivers that may reflect environmental changes. However, such information at the regional scale is still lacking due to methodological limitations. Beyond remote sensing indicators only recognizing vegetation productivity, we utilized multivariate data fusion and deep learning to characterize formation-based plant community structure in alpine grasslands at the regional scale of the Tibetan Plateau for the first time and compared it with the earlier version of Vegetation Map of China for historical changes. Over the past 40 years, we revealed that (1) the proportion of alpine meadows in alpine grasslands increased from 50% to 69%, well-reflecting the warming and wetting trend; (2) dominances of Kobresia pygmaea and Stipa purpurea formations in alpine meadows and steppes were strengthened to 76% and 92%, respectively; (3) the climate factor mainly drove the distribution of Stipa purpurea formation, but not the recent distribution of Kobresia pygmaea formation that was likely shaped by human activities. Therefore, the underlying mechanisms of grassland changes over the past 40 years were considered to be formation dependent. Overall, the first exploration for structural information of plant community changes in this study not only provides a new perspective to understand drivers of grassland changes and their spatial heterogeneity at the regional scale of the Tibetan Plateau, but also innovates large-scale vegetation study paradigm.
Subject(s)
Ecosystem , Grassland , Humans , Tibet , Climate Change , ChinaABSTRACT
OBJECTIVE: To explore the effects of soluble epoxide hydrolase inhibitor (sEHi) on the expressions of fatty acid synthase (FASN) mRNA and protein in peripheral blood mononuclear cell (PBMCs) of patients with acute coronary syndrome (ACS) and to discuss the influences of sEHi in the regulated expression of FASN and inflammatory reaction. METHODS: The hospitalized ACS patients were selected as the ACS group (n = 35) while the healthy normal subjects as the control group (n = 30). The levels of lipoproteins, fasting blood glucose, myocardial enzyme and hs-CRP (high-sensitive C-reactive protein) were measured within 24 hours after admission. Meanwhile the PBMCs were separated and cultured and then t-AUCB was added in various concentrations (0, 1, 10, 50, 100 µmol/L). The cellular expressions of FASN, IL-6 mRNA and protein were detected by real-time PCR (polymerase chain reaction) and Western blot respectively. RESULTS: (1) The serum concentration of hs-CRP reached (5.6 ± 4.1) mg/L in the ACS group. And it was obviously higher than (1.3 ± 0.9) mg/L in the control group (P < 0.05). Compared with the control group, the expression levels of FASN, IL-6 mRNA and protein significantly increased in the ACS group (the relative expression amount of FASN mRNA: 1 vs 1.709 ± 0.272, FASN protein: 0.407 ± 0.065 vs 1.298 ± 0.087; relative expression amount of IL-6 mRNA: 1 vs 2.302 ± 0.200, IL-6 protein: 0.715 ± 0.058 vs 1.146 ± 0.083, P < 0.05). Moreover, the levels of FASN and IL-6 mRNA had positive correlations with the serum concentration of hs-CRP (r = 0.714, P < 0.01; r = 0.685, P < 0.01). (2) Compared with the control group (t-AUCB 0 µmol/L), 10, 50, 100 µmol/L t-AUCB had inhibited the expressions quantity of FASN, IL-6 mRNA and protein in PBMCs from the ACS group (P < 0.05). The relative expressions of FASN mRNA in t-AUCB 0, 10, 50, 100 µmol/L group were 1, 0.813 ± 0.038, 0.564 ± 0.100, 0.293 ± 0.043 respectively. The relative expressions of FASN protein in t-AUCB 0, 10, 50 and 100 µmol/L group were 0.957 ± 0.280, 0.935 ± 0.275, 0.855 ± 0.253, 0.685 ± 0.206 respectively. CONCLUSION: The inflammatory level increases obviously in the ACS group. And the expression level of FASN in PBMCs is closely correlated with the inflammatory level in the ACS patients; t-AUCB may prevent the ruptures of atherosclerotic lesions by regulating FASN and inhibiting inflammatory reactions in ACS patients.
Subject(s)
Acute Coronary Syndrome/blood , Acute Coronary Syndrome/pathology , Benzoates/pharmacology , Epoxide Hydrolases/antagonists & inhibitors , Fatty Acid Synthase, Type I/metabolism , Inflammation , Urea/analogs & derivatives , Aged , Case-Control Studies , Female , Humans , Leukocytes, Mononuclear/metabolism , Male , Middle Aged , Urea/pharmacologyABSTRACT
Great saphenous varicose vein (GSVV) is a venous reflux disease of the lower extremity. In order to explore the clinical effect of subfascial endoscopic perforator surgery (SEPS) with endovenous laser treatment (EVLT) in the treatment of GSVV, 80 patients who underwent unilateral saphenous varicose surgery are analyzed. The operation results show that the patients who used SEPS + EVLT have less operation time and mean blood loss, shorter postoperative active time and hospitalization stay, better curative effect, and higher notch aesthetics (P < 0.05). SEPS combined with EVLT has a remarkable curative effect in the treatment of saphenous varicose veins of lower extremity, which can significantly shorten the hospitalization time of patients and improve the coagulation index and stress index.
Subject(s)
Saphenous Vein , Varicose Veins , Humans , Lasers , Saphenous Vein/surgery , Treatment Outcome , Varicose Veins/etiology , Varicose Veins/surgery , Vascular Surgical Procedures/adverse effects , Vascular Surgical Procedures/methodsABSTRACT
Globally, droughts are the most widespread climate factor impacting carbon (C) cycling. However, as the second-largest terrestrial C flux, the responses of soil respiration (Rs) to extreme droughts co-regulated by seasonal timing and PFT (plant functional type) are still not well understood. Here, a manipulative extreme-duration drought experiment (consecutive 30 days without rainfall) was designed to address the importance of drought timing (early-, mid-, or late growing season) for Rs and its components (heterotrophic respiration (Rh) and autotrophic respiration (Ra)) under three PFT treatments (two graminoids, two shrubs, and their combination). The results suggested that regardless of PFT, the mid-drought had the greatest negative effects while early-drought overall had little effect on Rh and its dominated Rs. However, PFT treatments had significant effects on Rh and Rs in response to the late drought, which was PFT-dependence: reduction in shrubs and combination but not in graminoids. Path analysis suggested that the decrease in Rs and Rh under droughts was through low soil water content induced reduction in MBC and GPP. These findings demonstrate that responses of Rs to droughts depend on seasonal timing and communities. Future droughts with different seasonal timing and induced shifts in plant structure would bring large uncertainty in predicting C dynamics under climate changes.
ABSTRACT
Global warming can trigger dramatic glacier area shrinkage and change the flux of glacial runoff, leading to the expansion and subsequent retreat of riparian wetlands. This elicits the interconversion of riparian wetlands and their adjacent ecosystems (e.g., alpine meadows), probably significantly impacting ecosystem nitrogen input by changing soil diazotrophic communities. However, the soil diazotrophic community differences between glacial riparian wetlands and their adjacent ecosystems remain largely unexplored. Here, soils were collected from riparian wetlands and their adjacent alpine meadows at six locations from glacier foreland to lake mouth along a typical Tibetan glacial river in the Namtso watershed. The abundance and diversity of soil diazotrophs were determined by real-time PCR and amplicon sequencing based on nifH gene. The soil diazotrophic community assembly mechanisms were analyzed via iCAMP, a recently developed null model-based method. The results showed that compared with the riparian wetlands, the abundance and diversity of the diazotrophs in the alpine meadow soils significantly decreased. The soil diazotrophic community profiles also significantly differed between the riparian wetlands and alpine meadows. For example, compared with the alpine meadows, the relative abundance of chemoheterotrophic and sulfate-respiration diazotrophs was significantly higher in the riparian wetland soils. In contrast, the diazotrophs related to ureolysis, photoautotrophy, and denitrification were significantly enriched in the alpine meadow soils. The iCAMP analysis showed that the assembly of soil diazotrophic community was mainly controlled by drift and dispersal limitation. Compared with the riparian wetlands, the assembly of the alpine meadow soil diazotrophic community was more affected by dispersal limitation and homogeneous selection. These findings suggest that the conversion of riparian wetlands and alpine meadows can significantly alter soil diazotrophic community and probably the ecosystem nitrogen input mechanisms, highlighting the enormous effects of climate change on alpine ecosystems.