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1.
Nat Commun ; 15(1): 5311, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38906891

RESUMO

To adapt to the complex belowground environment, plants make trade-offs between root resource acquisition and defence ability. This includes forming partnerships with different types of root associating microorganisms, such as arbuscular mycorrhizal and ectomycorrhizal fungi. These trade-offs, by mediating root chemistry, exert legacy effects on nutrient release during decomposition, which may, in turn, affect the ability of new roots to re-acquire resources, thereby generating a feedback loop. However, the linkages at the basis of this potential feedback loop remain largely unquantified. Here, we propose a trait-based root 'acquisition-defence-decomposition' conceptual framework and test the strength of relevant linkages across 90 angiosperm tree species. We show that, at the plant species level, the root-fungal symbiosis gradient within the root economics space, root chemical defence (condensed tannins), and root decomposition rate are closely linked, providing support to this framework. Beyond the dichotomy between arbuscular mycorrhizal-dominated versus ectomycorrhizal-dominated systems, we suggest a continuous shift in feedback loops, from 'high arbuscular mycorrhizal symbiosis-low defence-fast decomposition-inorganic nutrition' by evolutionarily ancient taxa to 'high ectomycorrhizal symbiosis-high defence-slow decomposition-organic nutrition' by more modern taxa. This 'acquisition-defence-decomposition' framework provides a foundation for testable hypotheses on multidimensional linkages between species' belowground strategies and ecosystem nutrient cycling in an evolutionary context.


Assuntos
Magnoliopsida , Micorrizas , Raízes de Plantas , Simbiose , Árvores , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo , Micorrizas/fisiologia , Árvores/microbiologia , Árvores/metabolismo , Magnoliopsida/microbiologia , Magnoliopsida/metabolismo
2.
Tree Physiol ; 44(1)2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-37738586

RESUMO

Plants allocate a substantial amount of C belowground for root exudates and for the construction and adjustment of root morphological and architectural traits. What relationships exist between root exudates and other root traits and these relationships change with growing season, however, remain unclear. We quantified the root exudation rate and root morphological traits, including total root length (RL), total root surface area (RS), root diameter (RD), specific root length (SRL), specific root area (SRA) and root tissue density (RTD), and architectural traits, such as branching intensity (BI), and investigated their associations during the rapidly growing season (April and August) and the slowly growing season (December) of three common native tree species, Liquidambar formosana, Michelia maudiae and Schima superba, in subtropical China. We found that the linkages of RD, SRL, SRA, RTD and BI did not change with the growing season, reflecting their highly conservative relationships. The root exudation rate varied significantly with growing season (P < 0.05) and produced various associations with other root traits at different growing seasons. During the rapidly growing season (i.e., April), the exudation rate was the highest and was positively correlated with RL. The exudation rate was the lowest during the slowly growing season (i.e., December) and was negatively associated with RL, RS and RTD. Our findings demonstrate the seasonality of the linkages of root exudation rate with other root traits, which highlights the highly plastic and complex associations of belowground root traits. These findings help to deepen our understanding of plant nutrient acquisition strategies.


Assuntos
Raízes de Plantas , Solo , Estações do Ano , Raízes de Plantas/anatomia & histologia , Plantas , Árvores
3.
Eur J Med Chem ; 258: 115546, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37302340

RESUMO

Tumors, a disease with a high mortality rate worldwide, have become a serious threat to human health. Exonucleotide-5'-nucleotidase (CD73) is an emerging target for tumor therapy. Its inhibition can significantly reduce adenosine levels in the tumor microenvironment. It has a better therapeutic effect on adenosine-induced immunosuppression. In the immune response, extracellular ATP exerts immune efficacy by activating T cells. However, dead tumor cells release excess ATP, overexpress CD39 and CD73 on the cell membrane and catabolize this ATP to adenosine. This leads to further immunosuppression. There are a number of inhibitors of CD73 currently under investigation. These include antibodies, synthetic small molecule inhibitors and a number of natural compounds with prominent roles in the anti-tumor field. However, only a small proportion of the CD73 inhibitors studied to date have successfully reached the clinical stage. Therefore, effective and safe inhibition of CD73 in oncology therapy still holds great therapeutic potential. This review summarizes the currently reported CD73 inhibitors, describes their inhibitory effects and pharmacological mechanisms, and provides a brief review of them. It aims to provide more information for further research and development of CD73 inhibitors.


Assuntos
5'-Nucleotidase , Neoplasias , Humanos , Adenosina/metabolismo , Imunoterapia , Neoplasias/tratamento farmacológico , Anticorpos , Trifosfato de Adenosina/metabolismo , Microambiente Tumoral
4.
Sci Total Environ ; 892: 164397, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37247732

RESUMO

As a tree species of shelterbelts, Populus popularis maintains significant ecological functions in arid and semiarid areas. However, stand transpiration (T) and canopy conductance (gc) dynamics of P. popularis are unclear in arid irrigated areas with shallow groundwater fluctuations. To better understand the responses of T and gc to meteorological factors, soil water, and shallow groundwater in arid areas, we observed the environmental conditions and sap flow of P. popularis, and quantified T and gc in three growing seasons of 2018-2020 in a typical arid area of China. Results showed T and gc ranged from 0.18 to 6.11 mm day-1 and 2.26-12.54 mm s-1 in 2018-2020, respectively. Solar radiation and vapor pressure deficit (VPD) were major drivers of T at daily scales. It was consistently found that T exponentially decreased with increasing groundwater table depth (GTD) and decreasing reference evapotranspiration in three years. gc is primarily influenced by VPD and is positively related to soil water content in 0-30 cm soil layer (SWC0-30 cm). Moreover, low SWC0-30 cm and deepening GTD jointly decreased T and gc by 22.45 % and 30.41 %, respectively. The response of gc to VPD was susceptible to groundwater fluctuations, and the synergistic influences of VPD and GTD on gc could be well described by the logarithmic function, especially in 2019. The sensitivity of gc to VPD and its variations under different environmental conditions suggested that a flexible stomatal regulation of transpiration occurred in the observed P. popularis with the arid climate and shallow groundwater. These findings provided the essential basis for the water use strategy of P. popularis and stand water resources management in arid regions.


Assuntos
Populus , Água , Água/fisiologia , Populus/fisiologia , Transpiração Vegetal/fisiologia , Solo , Estações do Ano , Árvores/fisiologia
5.
Tree Physiol ; 43(7): 1092-1103, 2023 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-37074159

RESUMO

Plant-soil feedback (PSF) is conventionally characterized by plant biomass growth, yet it remains unclear how PSF affects plant nutrient acquisition strategies (e.g., nutrient absorption and nutrient resorption) associated with plant growth, particularly under changing soil environments. A greenhouse experiment was performed with seedlings of Pinus elliottii Englem and conditioned soils of monoculture plantations (P. elliottii and Cunninghamia lanceolata Hook). Soil sterilization was designed to test plant phosphorus (P) acquisition strategy with and without native soil fungal communities. Soils from P. elliottii and C. lanceolata plantations were used to explore the specific soil legacy effects on two different P acquisition pathways (absorption and resorption). Phosphorus addition was also applied to examine the separate and combined effects of soil abiotic factors and soil fungal factors on P acquisition pathways. Due to diminished mycorrhizal symbiosis, PSF prompted plants to increasingly rely on P resorption under soil sterilization. In contrast, P absorption was employed preferentially in the heterospecific soil, where species-specific pathogenic fungi could not affect P absorption. Higher soil P availability diluted the effects of soil fungal factors on the trade-off between the two P acquisition pathways in terms of the absolute PSF. Moreover, P addition plays a limited role in terms of the relative PSF and does not affect the direction and strength of relative PSF. Our results reveal the role of PSF in regulating plant P acquisition pathways and highlight the interaction between mycorrhizal and pathogenic fungi as the underlying mechanism of PSF.


Assuntos
Micorrizas , Pinus , Solo , Fósforo/metabolismo , Raízes de Plantas , Retroalimentação , Pinus/metabolismo , Micorrizas/fisiologia , Plantas/metabolismo , Microbiologia do Solo
6.
Front Pharmacol ; 14: 1105880, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909153

RESUMO

As a pathological coagulation process, thrombus can lead to many serious diseases, including ischemic stroke, acute myocardial infarction (AMI), acute coronary syndrome (ACS), and deep venous thrombosis (DVT). And anticoagulant drugs are one of the most effective ways to prevent and treat these diseases. Although macromolecular anticoagulant drugs such as low molecular weight heparins (LMWHs) are widely used in the clinic, their characteristics of requiring injectable use hinder their further promotion in the clinic, and the disadvantages of oral anticoagulant drugs, such as warfarin and dabigatran etexilate, which can easily cause bleeding adverse effects, are also not addressed. Factor Xa (FXa) has gained attention because it lies at the intersection of the coagulation cascade pathways, whereas subsequently introduced Factor Xa inhibitors such as rivaroxaban and apixaban, among others, have gained market popularity because of their high potency for anticoagulation and high specificity for Factor Xa when administered orally. But some of the drawbacks that these Factor Xa inhibitors have simultaneously such as fewer indications and the lack of an effective reversal drug when bleeding occurs are urgently addressed. The development of new Factor Xa inhibitors therefore becomes one means of addressing these questions. This article summarizes the small molecule Factor Xainhibitors developed from 2015 to 2022, classifies them according to their scaffolds, focuses on the analysis of their structure-activity relationships, and provides a brief assessment of them.

7.
Metab Brain Dis ; 38(4): 1351-1364, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36905560

RESUMO

BACKGROUND: Histone deacetylase (HDAC) inhibitor-based therapeutic drug tolerance is a major obstacle to glioblastoma (GBM) treatment. Meanwhile, non-coding RNAs have been reported to be involved in the regulation of HDAC inhibitor (SAHA) tolerance in some human tumors. However, the relationship between circular RNAs (circRNAs) and SAHA tolerance is still unknown. Herein, we explored the role and mechanism of circ_0000741 on SAHA tolerance in GBM. METHODS: Circ_0000741, microRNA-379-5p (miR-379-5p), and tripartite motif-containing 14 (TRIM14) level were detected by real-time quantitative polymerase chain reaction (RT-qPCR). (4-5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), 5-ethynyl-2'-deoxyuridine (EdU), Colony formation, flow cytometry, and transwell assays were used to detect SAHA tolerance, proliferation, apoptosis, and invasion in SAHA-tolerant GBM cells. Western blot analysis of protein levels of E-cadherin, N-cadherin, and TRIM14. After Starbase2.0 analysis, the binding between miR-379-5p and circ_0000741 or TRIM14 was proved using a dual-luciferase reporter. The role of circ_0000741 on drug tolerance was assessed using a xenograft tumor model in vivo. RESULTS: Circ_0000741 and TRIM14 were upregulated, and miR-379-5p was reduced in SAHA-tolerant GBM cells. Furthermore, circ_0000741 absence reduced SAHA tolerance, suppressed proliferation, invasion, and induced apoptosis in SAHA-tolerant GBM cells. Mechanistically, circ_0000741 might affect TRIM14 content via sponging miR-379-5p. Besides, circ_0000741 silencing enhanced the drug sensitivity of GBM in vivo. CONCLUSION: Circ_0000741 might accelerate SAHA tolerance by regulating the miR-379-5p/TRIM14 axis, which provided a promising therapeutic target for GBM treatment.


Assuntos
Glioblastoma , MicroRNAs , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Inibidores de Histona Desacetilases/farmacologia , RNA Circular/genética , Tolerância a Medicamentos , MicroRNAs/genética , Proliferação de Células , Proteínas com Motivo Tripartido , Peptídeos e Proteínas de Sinalização Intracelular
8.
New Phytol ; 238(2): 612-623, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36647205

RESUMO

Unravelling belowground strategies is critical for understanding species coexistence and successional dynamics; yet, our knowledge of nutrient acquisition strategies of forest species at different successional stages remains limited. We measured morphological (diameter, specific root length, and root tissue density), architectural (branching ratio), physiological (ammonium, nitrate, and glycine uptake rates) root traits, and mycorrhizal colonisation rates of eight coexisting woody species in an early successional plantation forest in subtropical China. By incorporating physiological uptake efficiency, we revealed a bi-dimensional root economics space comprising of an 'amount-efficiency' dimension represented by morphological and physiological traits, and a 'self-symbiosis' dimension dominated by architectural and mycorrhizal traits. The early pioneer species relied on root-fungal symbiosis, developing densely branched roots with high mycorrhizal colonisation rates for foraging mobile soil nitrate. The late pioneer species invested in roots themselves and allocated effort towards improving uptake efficiency of less-mobile ammonium. Within the root economics space, the covariation of axes with soil phosphorus availability also distinguished the strategy preference of the two successional groups. These results demonstrate the importance of incorporating physiological uptake efficiency into root economics space, and reveal a trade-off between expanding soil physical space exploration and improving physiological uptake efficiency for successional species coexistence in forests.


Assuntos
Micorrizas , Árvores , Árvores/fisiologia , Raízes de Plantas/fisiologia , Nitratos , Florestas , Micorrizas/fisiologia , Solo
10.
Clin Transl Oncol ; 25(4): 1102-1113, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36477947

RESUMO

BACKGROUND: Doublecortin-like kinase 2 (DCLK2) is a microtubule-associated protein kinase that participates in neural development and maturation; however, whether it is involved in tumour progression remains unclear. METHODS: DCLK2 overexpression and knockdown clones were established by lentivirus transfection. Western blot, PCR assays and bioinformatics analyses were conducted to observe the expression of DCLK2. CCK8, colony formation, scratch migration and Transwell assays were used to detect cell proliferation, migration and invasion, respectively. Tumour metastasis was evaluated in vivo using a tail vein metastasis model. Bioinformatics analyses were performed to analyse the expression correlation between DCLK2 and TCF4, or EMT markers in breast cancer. RESULTS: Our data indicate that DCLK2 is highly expressed in breast cancer cells and is associated with poor prognosis. Silencing DCLK2 does not affect the proliferation rate of tumour cells, but significantly suppresses migration and invasion as well as lung metastasis processes. Overexpression of DCLK2 can enhance the migratory and invasive abilities of normal breast epithelial cells. Moreover, TCF4/ß-catenin inhibitor LF3 downregulates the expression of DCLK2 and inhibits the migration and invasion of breast cancer cells. Furthermore, we found that the downregulation of DCLK2 blocks the epithelial-mesenchymal transition (EMT) process. CONCLUSION: Our study indicates that DCLK2 plays an important role in EMT, cell invasion and metastasis, suggesting that DCLK2 is a potential target for the treatment of metastatic breast cancer.


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Humanos , Feminino , Quinases Semelhantes a Duplacortina , Linhagem Celular Tumoral , Neoplasias da Mama/patologia , Neoplasias Pulmonares/genética , Invasividade Neoplásica/genética , Transição Epitelial-Mesenquimal , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Metástase Neoplásica
11.
New Phytol ; 234(5): 1639-1653, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35243647

RESUMO

The root economics space (RES) is multidimensional and largely shaped by belowground biotic and abiotic influences. However, how root-fungal symbioses and edaphic fertility drive this complexity remains unclear. Here, we measured absorptive root traits of 112 tree species in temperate and subtropical forests of China, including traits linked to functional differences between arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) hosts. Our data, from known mycorrhizal tree species, revealed a 'fungal-symbiosis' dimension distinguishing AM from ECM species. This divergence likely resulted from the contrasting mycorrhizal evolutionary development of AM vs ECM associations. Increased root tissue cortical space facilitates AM symbiosis, whereas increased root branching favours ECM symbiosis. Irrespective of mycorrhizal type, a 'root-lifespan' dimension reflecting aspects of root construction cost and defence was controlled by variation in specific root length and root tissue density, which was fully independent of root nitrogen content. Within this function-based RES, we observed a substantial covariation of axes with soil phosphorus and nitrate levels, highlighting the role played by these two axes in nutrient acquisition and conservation. Overall, our findings demonstrate the importance of evolved mycorrhizal symbiosis pathway and edaphic fertility in framing the RES, and provide theoretical and mechanistic insights into the complexity of root economics.


Assuntos
Micorrizas , Fertilidade , Raízes de Plantas/metabolismo , Solo , Microbiologia do Solo , Simbiose , Árvores
12.
J Vis Exp ; (179)2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-35068478

RESUMO

The field of moxibustion research is expanding, with a rapid increase in publications in recent years. Moxibustion is a therapy that ignites moxa on the skin of humans, with an increase in peripheral skin temperature and localized redness. During this treatment, the recipient must remain still to prevent scalding and expose intervention sites for easy manipulation; however, maintaining a fixed posture during moxibustion is a big challenge for animals. Thus, manipulating moxibustion in small animals, such as mice, can lead to several difficulties for researchers. In addition, an uncomfortable posture for animals can lead to fear and resistance to moxibustion, increased risk of injury, diminished animal welfare, and less valid research data. An efficient, comfortable moxibustion method is needed to protect animal welfare and minimize the adverse effects on experimental results. However, moxibustion methods are highly variable and often have limited efficacy. More importantly, an uncomfortable moxibustion posture might cause a stress response, such as those observed with anxiety, fear, and anger, which could influence the research data. Therefore, strategies for animal moxibustion that inflict the least harm possible during the intervention are required. This protocol introduces a mouse tethering method for moxibustion intervention, minimizing mouse discomfort and improving study efficiency. Essential strategies for tethering mice and application of moxibustion are highlighted, and the structure of the tethering instrument is described.


Assuntos
Moxibustão , Pontos de Acupuntura , Bem-Estar do Animal , Animais , Camundongos , Pele , Temperatura Cutânea
13.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3521-3530, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676713

RESUMO

We explored the seasonal dynamics and climate responses of radial variation of Chinese fir, we continuously monitored intra-annual stem radial size changes with the automated dendrometers in central Jiangxi Province in 2016 and 2017. We analyzed daily and seasonal dynamics of radial variations, and their Spearman correlations with climatic factors. We found that the diurnal radial variations had a pattern of contraction during the day and expansion at night. The growth onset in 2017 was one month earlier than that in 2016, whereas the continuous tree water deficit in the dry season caused the cessation one month early. During the main growing season (from April to September), the radial increment was significantly positively correlated with precipitation and relative humidity but negatively correlated with photosynthetically active radiation and vapor pressure deficit in both wet and dry seasons. However, the correlation for tree water deficit was opposite to stem radial increment. Severe water deficit significantly enhanced the impacts of soil water content on stem radial variation in the dry season. Moisture condition was always the key factor affecting stem radial variation of Chinese fir. Appropriate measures such as increasing soil water content could promote stem radial growth during summer drought.


Assuntos
Cunninghamia , Secas , Clima , Estações do Ano , Árvores
14.
Life Sci ; 280: 119699, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34102196

RESUMO

The therapeutic effect of grain-sized moxibustion (GS-Moxi) on inflammatory pain has been well recognized clinically, but the mechanism remains unclear. STIM1/ORAI1 is a sensible temperature channel, therefore; this study aimed to investigate the analgesic effect of GS-Moxi and the association with STIM1/ORAI1 expression. CFA-induced inflammatory pain model was established and was treated with GS-Moxi after 3 days of CFA injection. The behavioral test was measured after the GS-Moxi; then, serum was prepared for IL-1ß, IL-6, and TNF-α, and the stimulated skin was used for measuring STIM1 and ORAI1 expression. The results indicated GS-Moxi had an analgesic effect on inflammatory pain and the heat variation was significant for the analgesia. GS-Moxi decreased the expression of IL-1ß, IL-6, and TNF-α. Immunofluorescence and western blot analysis illustrated that heat change was associated with the stimulation of STIM1 and ORAI1. Suggesting that heat variation created by GS-Moxi could be crucial in this therapy and STIM1 and ORAI1 were potential enhancers in regulating analgesia of GS-Moxi.


Assuntos
Inflamação/terapia , Moxibustão/métodos , Proteína ORAI1/metabolismo , Manejo da Dor/métodos , Molécula 1 de Interação Estromal/metabolismo , Animais , Modelos Animais de Doenças , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
15.
J Pharmacol Sci ; 145(2): 167-174, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33451751

RESUMO

Manganese chloride (MnCl2) has been shown to inhibit the Yes-associated protein (YAP) in high-fat diet-fed ApoE-/- mice. Although YAP has been implicated in atherogenesis, there are limited data on the effects of MnCl2 on cardiac remodeling. In this study, we discovered, by electrocardiography, that hyperlipidemia led to spontaneous supraventricular arrhythmia (SVA) in ApoE-/- (KO) mice, with 3 of 9 KO + MnCl2 mice (33%) exhibiting lower incidence of spontaneous SVA than KO mice (6 of 10 mice, 60%). Echocardiography revealed that reduced systolic function in KO mice was reversed by MnCl2 treatment. Oil Red O staining of the aortas and biochemical analysis of lipid levels showed that MnCl2 inhibited plaque formation in a lipid metabolism-independent manner. MnCl2 inhibited inflammatory cell infiltration and reduced fibrosis, as evidenced by hematoxylin and eosin, immunohistochemical and Masson's trichrome staining, respectively. Our findings demonstrate that spontaneous SVA and reduced systolic function were blocked by MnCl2. Our findings show that MnCl2 was useful in delaying cardiac remodeling and reducing susceptibility to spontaneous SVA in a mouse model of hyperlipidemia.


Assuntos
Cloretos/administração & dosagem , Hiperlipidemias/tratamento farmacológico , Compostos de Manganês/administração & dosagem , Taquicardia Supraventricular/prevenção & controle , Taquicardia Supraventricular/fisiopatologia , Remodelação Ventricular , Administração Oral , Animais , Cloretos/farmacologia , Modelos Animais de Doenças , Hiperlipidemias/complicações , Masculino , Compostos de Manganês/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Taquicardia Supraventricular/etiologia , Remodelação Ventricular/efeitos dos fármacos
16.
Tree Physiol ; 41(3): 403-415, 2021 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-33079181

RESUMO

Hydraulic capacitance and carbohydrate storage are two drought adaptation strategies of woody angiosperms. However, we currently lack information on their associations and how they are associated with species' degree of isohydry. We measured total stem xylem nonstructural carbohydrate (NSC) concentration in the dry and wet seasons, xylem hydraulic capacitance, native leaf water potentials, pressure-volume curve parameters and photosynthetic performance in 24 woody understory species differing in their degree of isohydry. We found a trade-off between xylem water and carbohydrate storage both in storage capacitance and along a spectrum of isohydry. Species with higher hydraulic capacitance had lower native NSC storage. The less isohydric species tended to show greater NSC depletion in the dry season and have more drought-tolerant leaves. In contrast, the more isohydric species had higher hydraulic capacitance, which may enhance their drought avoidance capacity. In these species, leaf flushing in the wet season and higher photosynthetic rates in the dry season resulted in accumulation rather than depletion of NSC in the dry season. Our results provide new insights into the mechanisms through which xylem storage functions determine co-occurring species' drought adaptation strategies and improve our capacity to predict community assembly processes under drought.


Assuntos
Árvores , Água , Carboidratos , Secas , Folhas de Planta , Xilema
17.
New Phytol ; 229(1): 284-295, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32761622

RESUMO

Traits are critical in predicting decomposition that fuels carbon and nutrient cycling in ecosystems. However, our understanding of root trait-decomposition linkage, and especially its dependence on mycorrhizal type and environmental context, remains limited. We explored the control of morphological and chemical (carbon- and nutrient-related) traits over decomposition of absorptive roots in 30 tree species associated with either arbuscular mycorrhizal (AM) or ectomycorrhizal (ECM) fungi in temperate and subtropical forests in China. Carbon-related traits (acid-unhydrolysable residue (AUR) and cellulose concentrations) had predominant control of root decomposition in AM species while nutrient-related traits (magnesium concentration) predominately controlled that in ECM species. Thicker absorptive roots decomposed faster in AM species as a result of their lower AUR concentrations, but more slowly in ECM angiosperm species potentially as a result of their higher magnesium concentrations. Root decomposition was linked to root nutrient economy in both forests while root diameter-decomposition coordination emerged only in the subtropical forest where root diameter and decomposition presented similar cross-species variations. Our findings suggest that root trait-decomposition linkages differ strongly with mycorrhizal type and environment, and that root diameter can predict decomposition but in opposing directions and with contrasting mechanisms for AM and ECM species.


Assuntos
Micorrizas , China , Ecossistema , Florestas , Nitrogênio , Raízes de Plantas , Árvores
18.
Medicine (Baltimore) ; 99(35): e22042, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32871961

RESUMO

BACKGROUND: Many cancer patients experience gastrointestinal adverse reaction during chemotherapy. Pharmacological interventions are commonly used to treat chemotherapy-induced gastrointestinal side effects but have various limitations. Clinical trials have indicated that moxibustion may alleviate gastrointestinal dysfunction and improve quality of life (QoL) after chemotherapy. This study aims to assess the efficacy and safety of moxibustion for chemotherapy-induced gastrointestinal adverse reaction through a systematic review and meta-analysis. METHODS: All randomized controlled trials (RCTs) related to moxibution targeting chemotherapy-induced gastrointestinal adverse reaction will be searched in online databases, such as PubMed, EMBASE, the Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), the Chinese Scientific Journal Database (VIP Database) and WanFang Database from their inception to May 1, 2020. The primary outcome is the incidence and severity of chemotherapy-related gastrointestinal toxicities (nausea and vomiting, diarrhea and constipation). The secondary outcomes include the quality of life, biological parameters' alteration, and adverse events. Study selection, data extraction, and assessment of risk of bias will be performed independently by 2 researchers. The Cochrane Collaboration's Review Manager (RevMan 5.3) software will be used to conduct the direct meta-analysis. RESULTS: This study will provide a comprehensive review of the available evidence for the treatment of chemotherapy-induced gastrointestinal adverse reaction with moxibustion. CONCLUSION: The conclusion of this study will provide evidence to judge whether moxibustion is an effective and safety therapeutic intervention for chemotherapy-induced gastrointestinal adverse reaction. PROSPERO REGISTRATION NUMBER: CRD42020182990.


Assuntos
Gastroenteropatias/terapia , Moxibustão , Antineoplásicos/efeitos adversos , Gastroenteropatias/induzido quimicamente , Humanos , Metanálise como Assunto , Revisões Sistemáticas como Assunto
19.
Ann Transl Med ; 8(10): 644, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32566581

RESUMO

BACKGROUND: Myocardial ischemia/reperfusion (I/R) injury has become a global public health concern. An increasing amount of evidence has shown that polyphyllin I (PPI) has anti-apoptotic and antioxidant functions. This study was performed to evaluate the cardioprotective effects of PPI in a rat model of myocardial I/R injury and the underlying mechanism. METHODS: We exposed induced a rat model of I/R injury by exposing rat hearts to left anterior descending coronary artery ligation for 30 min, followed by 24 h of reperfusion. Cardiac function was analyzed by echocardiography and HE staining. Myocardial apoptosis, inflammation, and oxidative stress were detected to analyze the PPI's role in I/R injury. RESULTS: The results showed that pretreatment with PPI improved impaired histological morphology, as shown by histopathological examination. Echocardiography analysis showed that PPI increased the levels of HR, left ventricular ejection fraction (LVEF), and left ventricular wall thickness (LVWT), accompanied by decreased left ventricular end-systolic volume (LVESV). Also, PPI decreased the expression of CK-MB, Mb, cTnI, and LDH. Specifically, PPI also changed the expression of apoptotic makers (Caspase-3, Bax, and Bcl-2), inflammatory cytokines (TNF-α, IL-6, iNOS, and IL-10) and oxidative stress markers (SOD, GSH, ROS, and MDA). Notably, western blot (WB) showed that PPI treatment inhibited the phosphorylation activity of NF-κB p65. CONCLUSIONS: The findings showed that PPI exerted a favorable protective effect on I/R injury by inhibiting the inflammatory response and oxidative stress. It offered new drug candidates for the treatment of myocardial I/R injury.

20.
Elife ; 92020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32589142

RESUMO

Plant species diversity affects carbon and nutrient cycling during litter decomposition, yet the generality of the direction of this effect and its magnitude remains uncertain. With a meta-analysis including 65 field studies across the Earth's major forest ecosystems, we show here that decomposition was faster when litter was composed of more than one species. These positive biodiversity effects were mostly driven by temperate forests but were more variable in other forests. Litter mixture effects emerged most strongly in early decomposition stages and were related to divergence in litter quality. Litter diversity also accelerated nitrogen, but not phosphorus release, potentially indicating a decoupling of nitrogen and phosphorus cycling and perhaps a shift in ecosystem nutrient limitation with changing biodiversity. Our findings demonstrate the importance of litter diversity effects for carbon and nutrient dynamics during decomposition, and show how these effects vary with litter traits, decomposer complexity and forest characteristics.


Assuntos
Biodiversidade , Florestas , Solo , Carbono/metabolismo , Modelos Biológicos , Nutrientes/metabolismo , Folhas de Planta , Análise Espaço-Temporal
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