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1.
Adv Sci (Weinh) ; : e2308176, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39024521

ABSTRACT

Microbial carbon (C) use efficiency (CUE) delineates the proportion of organic C used by microorganisms for anabolism and ultimately influences the amount of C sequestered in soils. However, the key factors controlling CUE remain enigmatic, leading to considerable uncertainty in understanding soil C retention and predicting its responses to global change factors. Here, we investigate the global patterns of CUE estimate by stoichiometric modeling in surface soils of natural ecosystems, and examine its associations with temperature, precipitation, plant-derived C and soil nutrient availability. We found that CUE is determined by the most limiting resource among these four basic environmental resources within specific climate zones (i.e., tropical, temperate, arid, and cold zones). Higher CUE is common in arid and cold zones and corresponds to limitations in temperature, water, and plant-derived C input, while lower CUE is observed in tropical and temperate zones with widespread limitation of nutrients (e.g., nitrogen or phosphorus) in soil. The contrasting resource limitations among climate zones led to an apparent increase in CUE with increasing latitude. The resource-specific dependence of CUE implies that soils in high latitudes with arid and cold environments may retain less organic C in the future, as warming and increased precipitation can reduce CUE. In contrast, oligotrophic soils in low latitudes may increase organic C retention, as CUE could be increased with concurrent anthropogenic nutrient inputs. The findings underscore the importance of resource limitations for CUE and suggest asymmetric responses of organic C retention in soils across latitudes to global change factors.

2.
BMC Plant Biol ; 24(1): 387, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38724946

ABSTRACT

BACKGROUND: Woody bamboos are the only diverse large perennial grasses in mesic-wet forests and are widely distributed in the understory and canopy. The functional trait variations and trade-offs in this taxon remain unclear due to woody bamboo syndromes (represented by lignified culm of composed internodes and nodes). Here, we examined the effects of heritable legacy and occurrence site climates on functional trait variations in leaf and culm across 77 woody bamboo species in a common garden. We explored the trade-offs among leaf functional traits, the connection between leaf nitrogen (N), phosphorus (P) concentrations and functional niche traits, and the correlation of functional traits between leaves and culms. RESULTS: The Bayesian mixed models reveal that the combined effects of heritable legacy (phylogenetic distances and other evolutionary processes) and occurrence site climates accounted for 55.10-90.89% of the total variation among species for each studied trait. The standardized major axis analysis identified trade-offs among leaf functional traits in woody bamboo consistent with the global leaf economics spectrum; however, compared to non-bamboo species, the woody bamboo exhibited lower leaf mass per area but higher N, P concentrations and assimilation, dark respiration rates. The canonical correlation analysis demonstrated a positive correlation (ρ = 0.57, P-value < 0.001) between leaf N, P concentrations and morphophysiology traits. The phylogenetic principal components and trait network analyses indicated that leaf and culm traits were clustered separately, with leaf assimilation and respiration rates associated with culm ground diameter. CONCLUSION: Our study confirms the applicability of the leaf economics spectrum and the biogeochemical niche in woody bamboo taxa, improves the understanding of woody bamboo leaf and culm functional trait variations and trade-offs, and broadens the taxonomic units considered in plant functional trait studies, which contributes to our comprehensive understanding of terrestrial forest ecosystems.


Subject(s)
Nitrogen , Plant Leaves , Plant Leaves/physiology , Plant Leaves/genetics , Nitrogen/metabolism , Sasa/genetics , Sasa/physiology , Poaceae/genetics , Poaceae/physiology , Phosphorus/metabolism , Phylogeny , Bayes Theorem
3.
Glob Chang Biol ; 29(12): 3503-3515, 2023 06.
Article in English | MEDLINE | ID: mdl-36934319

ABSTRACT

Microbial necromass is an important source and component of soil organic matter (SOM), especially within the most stable pools. Global change factors such as anthropogenic nitrogen (N), phosphorus (P), and potassium (K) inputs, climate warming, elevated atmospheric carbon dioxide (eCO2 ), and periodic precipitation reduction (drought) strongly affect soil microorganisms and consequently, influence microbial necromass formation. The impacts of these global change factors on microbial necromass are poorly understood despite their critical role in the cycling and sequestration of soil carbon (C) and nutrients. Here, we conducted a meta-analysis to reveal general patterns of the effects of nutrient addition, warming, eCO2 , and drought on amino sugars (biomarkers of microbial necromass) in soils under croplands, forests, and grasslands. Nitrogen addition combined with P and K increased the content of fungal (+21%), bacterial (+22%), and total amino sugars (+9%), consequently leading to increased SOM formation. Nitrogen addition alone increased solely bacterial necromass (+10%) because the decrease of N limitation stimulated bacterial more than fungal growth. Warming increased bacterial necromass, because bacteria have competitive advantages at high temperatures compared to fungi. Other global change factors (P and NP addition, eCO2 , and drought) had minor effects on microbial necromass because of: (i) compensation of the impacts by opposite processes, and (ii) the short duration of experiments compared to the slow microbial necromass turnover. Future studies should focus on: (i) the stronger response of bacterial necromass to N addition and warming compared to that of fungi, and (ii) the increased microbial necromass contribution to SOM accumulation and stability under NPK fertilization, and thereby for negative feedback to climate warming.


Subject(s)
Soil Microbiology , Soil , Forests , Climate Change , Nitrogen/analysis , Bacteria
4.
Front Oncol ; 12: 1068198, 2022.
Article in English | MEDLINE | ID: mdl-36568178

ABSTRACT

Background: Prediction of prognosis for patients with esophageal cancer(EC) is beneficial for their postoperative clinical decision-making. This study's goal was to create a dependable machine learning (ML) model for predicting the prognosis of patients with EC after surgery. Methods: The files of patients with esophageal squamous cell carcinoma (ESCC) of the thoracic segment from China who received radical surgery for EC were analyzed. The data were separated into training and test sets, and prognostic risk variables were identified in the training set using univariate and multifactor COX regression. Based on the screened features, training and validation of five ML models were carried out through nested cross-validation (nCV). The performance of each model was evaluated using Area under the curve (AUC), accuracy(ACC), and F1-Score, and the optimum model was chosen as the final model for risk stratification and survival analysis in order to build a valid model for predicting the prognosis of patients with EC after surgery. Results: This study enrolled 810 patients with thoracic ESCC. 6 variables were ultimately included for modeling. Five ML models were trained and validated. The XGBoost model was selected as the optimum for final modeling. The XGBoost model was trained, optimized, and tested (AUC = 0.855; 95% CI, 0.808-0.902). Patients were separated into three risk groups. Statistically significant differences (p < 0.001) were found among all three groups for both the training and test sets. Conclusions: A ML model that was highly practical and reliable for predicting the prognosis of patients with EC after surgery was established, and an application to facilitate clinical utility was developed.

5.
Glob Chang Biol ; 28(16): 4977-4988, 2022 08.
Article in English | MEDLINE | ID: mdl-35617026

ABSTRACT

The carbon use efficiency (CUE) of soil microorganisms is a critical parameter for the first step of organic carbon (C) transformation by and incorporation into microbial biomass and shapes C cycling in terrestrial ecosystems. As C and nitrogen (N) cycles interact closely and N availability affects microbial metabolism, N addition to soil may shift the microbial CUE. We conducted a meta-analysis (100 data pairs) to generalize information about the microbial CUE response to N addition in soil based on the two most common CUE estimation approaches: (i) 13 C-labelled substrate addition (13 C-substrate) and (ii) 18 O-labelled water addition (18 O-H2 O). The mean microbial CUE in soils across all biomes and approaches was 0.37. The effects of N addition on CUE, however, were depended on the approach: CUE decreased by 12% if measured by the 13 C-substrate approach, while CUE increased by 11% if measured by the 18 O-H2 O approach. These differences in the microbial CUE response depending on the estimation approach are explained by the divergent reactions of microbial growth to N addition: N addition decreases the 13 C incorporation into microbial biomass (this parameter is in the numerator by CUE calculation based on the 13 C-substrate approach). In contrast, N addition slightly increases (although statistically insignificant) the microbial growth rate (in the numerator of the CUE calculation when assessed by the 18 O-H2 O approach), significantly raising the CUE. We explained these N addition effects based on CUE regulation mechanisms at the metabolic, cell, community, and ecosystem levels. Consequently, the differences in the microbial responses (microbial growth, respiration, C incorporation, community composition, and dormant or active states) between the 13 C-substrate and 18 O-H2 O approaches need to be considered. Thus, these two CUE estimation approaches should be compared to understand microbially mediated C and nutrient dynamics under increasing anthropogenic N input and other global change effects.


Subject(s)
Carbon , Soil , Biomass , Carbon/analysis , Ecosystem , Nitrogen/analysis , Soil/chemistry , Soil Microbiology
6.
Dis Esophagus ; 35(10)2022 Oct 14.
Article in English | MEDLINE | ID: mdl-35373248

ABSTRACT

BACKGROUND AND PURPOSE: This meta-analysis assesses the surgical outcomes between robot-assisted minimally-invasive McKeown esophagectomy and conventional one. METHOD: This meta-analysis searched the Web of Science, PUBMED, and EMBASE from the database's inception to January 2022. Altogether, 1073 records were identified in the literature search. Studies that evaluated the outcomes between robot-assisted minimally-invasive McKeown esophagectomy and conventional one among postoperative patients with oesophageal neoplasms were included. The assessed outcomes involved complications and clinical outcomes. In addition, heterogeneity was analyzed, and evidence quality was evaluated. RESULT: Evidence indicated that RAMIE (minimally-invasive esophagectomy assisted with robot) decreased incidences of lung complications and hospital stay as well as increased harvested lymph nodes. CONCLUSIONS: There was currently little evidence from randomized studies depicting that robot surgery manifested a clear overall advantage, but there was growing evidence regarding the clinical benefits of robot-assisted minimally invasive McKeown esophagectomy over conventional one.


Subject(s)
Esophageal Neoplasms , Robotic Surgical Procedures , Robotics , Esophageal Neoplasms/pathology , Esophagectomy/adverse effects , Humans , Minimally Invasive Surgical Procedures/adverse effects , Postoperative Complications/etiology , Postoperative Complications/surgery , Retrospective Studies , Robotic Surgical Procedures/adverse effects , Treatment Outcome
7.
Sci Total Environ ; 833: 155163, 2022 Aug 10.
Article in English | MEDLINE | ID: mdl-35413342

ABSTRACT

Nitrogen (N) and phosphorus (P) control biogeochemical cycling in terrestrial ecosystems. However, N and P addition effects on litter decomposition, especially biological pathways in subtropical forests, remain unclear. Here, a two-year field litterbag experiment was employed in a subtropical forest in southwestern China to examine N and P addition effects on litter biological decomposition with nine treatments: low and high N- and P-only addition (LN, HN, LP, and HP), NP coaddition (LNLP, LNHP, HNLP, and HNHP), and a control (CK). The results showed that the decomposition coefficient (k) was higher in NP coaddition treatments (P < 0.05), and lower in N- and P-only addition treatments than in CK (P < 0.05). The highest k was observed with LNLP (P < 0.05). The N- and P-only addition treatments decreased the losses of litter mass, lignin, cellulose, and condensed tannins, litter microbial biomass carbon (MBC), litter cellulase, and soil pH (P < 0.05). The NP coaddition treatments increased the losses of litter mass, lignin, and cellulose, MBC concentration, litter invertase, urease, cellulase, and catalase activities, soil arthropod diversity (S) in litterbags, and soil pH (P < 0.05). Litter acid phosphatase activity and N:P ratio were lower in N-only addition treatments but higher in P-only addition and NP coaddition treatments than in CK (P < 0.05). Structural equation model showed that litter MBC, S, cellulase, acid phosphatase, and polyphenol oxidase contributed to the loss of litter mass (P < 0.05). The litter N:P ratio was negatively logarithmically correlated with mass loss (P < 0.01). In conclusion, the negative effect of N addition on litter decomposition was reversed when P was added by increasing decomposed litter soil arthropod diversity, MBC concentration, and invertase and cellulase activities. Finally, the results highlighted the important role of the N:P ratio in litter decomposition.


Subject(s)
Cellulases , Nitrogen , Acid Phosphatase/metabolism , Carbon/analysis , Cellulases/analysis , Cellulases/metabolism , China , Ecosystem , Forests , Lignin/metabolism , Nitrogen/analysis , Phosphorus/analysis , Plant Leaves/chemistry , Soil/chemistry , beta-Fructofuranosidase/analysis , beta-Fructofuranosidase/metabolism
8.
BMC Res Notes ; 15(1): 99, 2022 Mar 10.
Article in English | MEDLINE | ID: mdl-35272671

ABSTRACT

OBJECTIVE: Adaptive laboratory evolution (ALE) is an effective approach to study the evolution behavior of bacterial cultures and to select for strains with desired metabolic features. In this study, we explored the possibility of evolving Thermotoga sp. strain RQ7 for cellulose-degrading abilities. RESULTS: Wild type RQ7 strain was subject to a series of transfers over six and half years with cellulose filter paper as the main and eventually the sole carbon source. Each transfer was accompanied with the addition of 50 µg of Caldicellulosiruptor saccharolyticus DSM 8903 genomic DNA. A total of 331 transfers were completed. No cellulose degradation was observed with the RQ7 cultures. Thirty three (33) isolates from six time points were sampled and sequenced. Nineteen (19) of the 33 isolates were unique, and the rest were duplicated clones. None of the isolates acquired C. saccharolyticus DNA, but all accumulated small-scale mutations throughout their genomes. Sequence analyses revealed 35 mutations that were preserved throughout the generations and another 15 mutations emerged near the end of the study. Many of the affected genes participate in phosphate metabolism, substrate transport, stress response, sensory transduction, and gene regulation.


Subject(s)
Carbon , Laboratories , Adaptation, Physiological/genetics , Base Sequence , Thermotoga
9.
Artif Cells Nanomed Biotechnol ; 47(1): 2265-2273, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31184221

ABSTRACT

Retinoblastoma is a rare cancer of the immature retina. This study designed to see the function of the lncRNA ANRIL in retinoblastoma Y79 cells. ANRIL, miR-99a and c-Myc expression in Y79 cells was altered by transfection and then trypan blue, transwell assay and flow cytometry were carried out to evaluate the changes of cell phenotype. The connection between ANRIL, miR-99a and c-Myc was measured by luciferase reporter assay and RNA immunoprecipitation analysis. As a result, ANRIL expression was highly expressed in human retinoblastoma tissue as relative to the adjacent noncancerous tissues. ANRIL suppression inhibited Y79 cells viability, migration, invasion, while promoted apoptosis. ANRIL negatively regulated miR-99a by binding to miR-99a. Silence of miR-99a reversed the ANRIL-knockdown effects on Y79 cells. miR-99a overexpression suppressed Y79 cell viability, migration, invasion, and enhanced apoptosis through downregulating c-Myc. Meanwhile, we found that miR-99a inhibited JAK/STAT and PI3K/AKT pathways. To conclude, it seems that ANRIL suppression inhibits cell growth and metastasis in retinoblastoma Y79 cells by regulating miR-99a and c-Myc.


Subject(s)
Apoptosis/genetics , Gene Silencing , MicroRNAs/genetics , Proto-Oncogene Proteins c-myc/genetics , RNA, Long Noncoding/genetics , Retinoblastoma/pathology , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Humans , Neoplasm Invasiveness , RNA, Long Noncoding/metabolism
10.
Int J Biol Macromol ; 115: 600-607, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29627466

ABSTRACT

Oxidative damage of retinal pigment epithelium (RPE) cells is involved in the pathogenesis age related macular degeneration (AMD). The purpose of this study was to evaluate the potential protective effect of a purified green tea polysaccharide (GTWP) against hydrogen peroxide (H2O2) induced oxidative stress and apoptosis in human retinal pigment epithelial cells (ARPE-19 cells). Human ARPE-19 cells were treated with 1 h of 500 µM H2O2 before incubation with GTWP for 24 h. Pretreatment of GTWP decreased H2O2-induced cell death and cell apoptosis, and efficiently suppressed the intracellular ROS production and malondialdehyde (MDA) generation induced by H2O2 treatment. Moreover, a loss of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione (GSH) activities were restored to normal level in H2O2-induced ARPE-19 cells upon GTWP (100 µg/ml) exposure. Also, the tendency of increased protein expression of Bax and cleaved-caspsae-3, as well as decrease of Bcl-2 protein in ARPE-19 cells challenged with H2O2 was changed to individual opposite way, thus inhibiting the apoptotic cell death. Our results demonstrated that GTWP protected RPE cells against oxidative injury through activation of anti-apoptotic and endogenous antioxidant enzymes signaling pathway, suggesting GTWP has attractive therapeutic potential to AMD.


Subject(s)
Apoptosis/drug effects , Camellia sinensis/chemistry , Endothelial Cells/drug effects , Hydrogen Peroxide/pharmacology , Oxidative Stress/drug effects , Polysaccharides/pharmacology , Retina/cytology , Antioxidants/metabolism , Cell Line , Cytoprotection/drug effects , Endothelial Cells/cytology , Endothelial Cells/metabolism , Glutathione/metabolism , Humans , Lipid Peroxidation/drug effects , Polysaccharides/isolation & purification
11.
Genome Announc ; 6(6)2018 Feb 08.
Article in English | MEDLINE | ID: mdl-29439028

ABSTRACT

Here, we report the draft genome sequence of Anaeromicrobium sediminis DY2726D, isolated from a west Pacific Ocean sediment sample. The genome comprises 4,710,590 bp in 56 contigs, with a G+C content of 31.2%. A total of 3,811 protein-coding sequences were predicted. The genome annotation revealed that DY2726D may represent a marine type of Clostridiaceae.

12.
Stand Genomic Sci ; 12: 62, 2017.
Article in English | MEDLINE | ID: mdl-29046741

ABSTRACT

Thermotoga sp. strain RQ7 is a member of the family Thermotogaceae in the order Thermotogales. It is a Gram negative, hyperthermophilic, and strictly anaerobic bacterium. It grows on diverse simple and complex carbohydrates and can use protons as the final electron acceptor. Its complete genome is composed of a chromosome of 1,851,618 bp and a plasmid of 846 bp. The chromosome contains 1906 putative genes, including 1853 protein coding genes and 53 RNA genes. The genetic features pertaining to various lateral gene transfer mechanisms are analyzed. The genome carries a complete set of putative competence genes, 8 loci of CRISPRs, and a deletion of a well-conserved Type II R-M system.

13.
Int J Ophthalmol ; 7(5): 837-42, 2014.
Article in English | MEDLINE | ID: mdl-25349803

ABSTRACT

AIM: To explore the efficacy of preoperative intravitreal bevacizumab (IVB) injection combined with Ahmed glaucoma valve (AGV) implantation in the treatment of neovascular glaucoma (NVG). METHODS: This retrospective study included 35 eyes from 35 patients who underwent preoperative IVB and AGV implantation for treatment of NVG. Findings such as intraocular pressure (IOP) number of anti-glaucoma medications, visual acuity (VA), surgical success rates, and complications were recorded. RESULTS: After AGV implantation, IOP was 18.2±4.0 mm Hg, 15.5±3.3 mm Hg and 9.8±2.6 mm Hg at 6, 12 and 36mo, significantly decreased compared with pre-IOP (P<0.01). The number of anti-glaucoma medications was 0.9±0.5, 0.8±0.9 and 0.8±0.6 at 6, 12 and 36mo, significantly decreased compared to pre-treatment (P<0.01). At last visit, there were 19 eyes with stable VA, 4 with VA improvement, 12 with diminished VA and 3 with complete loss light perception. There were 7 cases that failed during 3-year fellow up period. Cumulative probabilities of valve survival by Kaplan-Meier analysis were 82.9%, 74.1% and 71.0% at 12, 24 and 36mo, respectively. Cox stepwise regression analysis found that the survival time was significant associated with the pre-visual acuity <2/400 (P<0.05). Post-operative complications occurred in 8 eyes, of which hyphema presented in 2 eyes, choroidal effusion in 2 eyes. CONCLUSION: The procedure of preoperative IVB and AGV implantation should be one of treatments for NVG because of its safety and effectiveness.

14.
Exp Ther Med ; 5(5): 1310-1314, 2013 May.
Article in English | MEDLINE | ID: mdl-23737870

ABSTRACT

Carotid artery stenosis is a notable cause of ocular ischemic disease. To analyze the ocular ischemic diseases caused by carotid artery stenosis and to seek effective treatment, a retrospective review of 182 patients with carotid artery stenosis was performed. These patients were administered medical treatment, carotid artery stenting (CAS) or carotid endarterectomy (CEA) and the curative effects of the three different treatments were compared. The results demonstrated that all three treatments helped to improve the disease. Both carotid endarterectomy and carotid artery stenting were more effective than medical treatment (P<0.05). There was no significant difference between carotid endarterectomy and carotid artery stenting (P>0.05). In conclusion, timely diagnosis and suitable treatment for ocular ischemic diseases caused by carotid artery stenosis are necessary due to the complicated clinical manifestation. This study suggested that carotid endarterectomy and carotid artery stenting are effective techniques that may relieve this disease.

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