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1.
Immune infiltration of ovarian cancer (OV) is a critical factor in determining patient''s prognosis. Using data from TCGA and GTEx database combined with WGCNA and ESTIMATE methods, 46 genes related to OV occurrence and immune infiltration were identified. Lasso and multivariate Cox regression were applied to define a prognostic score (IGCI score) based on 3 immune genes and 3 types of clinical information. The IGCI score has been verified by K‐M curves, ROC curves and C‐index on test set. In test set, IGCI score (C‐index = 0.630) is significantly better than AJCC stage (C‐index = 0.541, p < 0.05) and CIN25 (C‐index = 0.571, p < 0.05). In addition, we identified key mutations to analyse prognosis of patients and the process related to immunity. Chi‐squared tests revealed that 6 mutations are significantly (p < 0.05) related to immune infiltration: BRCA1, ZNF462, VWF, RBAK, RB1 and ADGRV1. According to mutation survival analysis, we found 5 key mutations significantly related to patient prognosis (p < 0.05): CSMD3, FLG2, HMCN1, TOP2A and TRRAP. RB1 and CSMD3 mutations had small p‐value (p < 0.1) in both chi‐squared tests and survival analysis. The drug sensitivity analysis of key mutation showed when RB1 mutation occurs, the efficacy of six anti‐tumour drugs has changed significantly (p < 0.05).  相似文献   

2.
《Aging cell》2021,20(6)
Clonal hematopoiesis of indeterminate potential (CHIP) is a common precursor state for blood cancers that most frequently occurs due to mutations in the DNA‐methylation modifying enzymes DNMT3A or TET2. We used DNA‐methylation array and whole‐genome sequencing data from four cohorts together comprising 5522 persons to study the association between CHIP, epigenetic clocks, and health outcomes. CHIP was strongly associated with epigenetic age acceleration, defined as the residual after regressing epigenetic clock age on chronological age, in several clocks, ranging from 1.31 years (GrimAge, p < 8.6 × 10−7) to 3.08 years (EEAA, p < 3.7 × 10−18). Mutations in most CHIP genes except DNA‐damage response genes were associated with increases in several measures of age acceleration. CHIP carriers with mutations in multiple genes had the largest increases in age acceleration and decrease in estimated telomere length. Finally, we found that ~40% of CHIP carriers had acceleration >0 in both Hannum and GrimAge (referred to as AgeAccelHG+). This group was at high risk of all‐cause mortality (hazard ratio 2.90, p < 4.1 × 10−8) and coronary heart disease (CHD) (hazard ratio 3.24, p < 9.3 × 10−6) compared to those who were CHIP−/AgeAccelHG−. In contrast, the other ~60% of CHIP carriers who were AgeAccelHG− were not at increased risk of these outcomes. In summary, CHIP is strongly linked to age acceleration in multiple clocks, and the combination of CHIP and epigenetic aging may be used to identify a population at high risk for adverse outcomes and who may be a target for clinical interventions.  相似文献   

3.
ObjectiveDue to limited immunological profiles of high‐grade serous ovarian cancer (HGSOC), we aimed to characterize its molecular features to determine whether a specific subset that can respond to immunotherapy exists.Materials and MethodsA training cohort of 418 HGSOC samples from TCGA was analysed by consensus non‐negative matrix factorization. We correlated the expression patterns with the presence of immune cell infiltrates, immune regulatory molecules and other genomic or epigenetic features. Two independent cohorts containing 482 HGSOCs and in vitro experiments were used for validation.ResultsWe identified immune and non‐immune groups where the former was enriched in signatures that reflect immune cells, infiltration and PD‐1 signalling (all, P < 0.001), and presented with a lower chromosomal aberrations but increased neoantigens, tumour mutation burden, and microsatellite instability (all, P < 0.05); this group was further refined into two microenvironment‐based subtypes characterized by either immunoactivation or carcinoma‐associated fibroblasts (CAFs) and distinct prognosis. CAFs‐immune subtype was enriched for factors that mediate immunosuppression and promote tumour progression, including highly expressed stromal signature, TGF‐β signalling, epithelial‐mesenchymal transition and tumour‐associated M2‐polarized macrophages (all, P < 0.001). Robustness of these immune‐specific subtypes was verified in validation cohorts, and in vitro experiments indicated that activated‐immune subtype may benefit from anti‐PD1 antibody therapy (P < 0.05).ConclusionOur findings revealed two immune subtypes with different responses to immunotherapy and indicated that some HGSOCs may be susceptible to immunotherapies or combination therapies.  相似文献   

4.
The high‐altitude environment may drive vertebrate evolution in a certain way, and vertebrates living in different altitude environments might have different energy requirements. We hypothesized that the high‐altitude environment might impose different influences on vertebrate mitochondrial genomes (mtDNA). We used selection pressure analyses and PIC (phylogenetic independent contrasts) analysis to detect the evolutionary rate of vertebrate mtDNA protein‐coding genes (PCGs) from different altitudes. The results showed that the ratio of nonsynonymous/synonymous substitutions (dN/dS) in the mtDNA PCGs was significantly higher in high‐altitude vertebrates than in low‐altitude vertebrates. The seven rapidly evolving genes were shared by the high‐altitude vertebrates, and only one positive selection gene (ND5 gene) was detected in the high‐altitude vertebrates. Our results suggest the mtDNA evolutionary rate in high‐altitude vertebrates was higher than in low‐altitude vertebrates as their evolution requires more energy in a high‐altitude environment. Our study demonstrates the high‐altitude environment (low atmospheric O2 levels) drives vertebrate evolution in mtDNA PCGs.  相似文献   

5.
Sex is one of the important factors affecting gut microbiota. As key predators in agroforestry ecosystem, many spider species show dramatically different activity habits and nutritional requirements between females and males. However, how sex affects gut microbiota of spiders remains unclear. Here, we compared the composition and diversity of gut bacteria between female and male Pardosa astrigera based on bacterial 16S rRNA gene sequencing. Results showed that the richness of bacterial microbiota in female spiders was significantly lower than in male spiders (p < .05). Besides, β‐diversity showed a significant difference between female and male spiders (p = .0270). The relative abundance of Actinobacteriota and Rhodococcus (belongs to Actinobacteriota) was significantly higher in female than in male spiders (p < .05), whereas the relative abundance of Firmicutes and Acinetobacter (belongs to Proteobacteria) and Ruminococcus and Fusicatenibacter (all belong to Firmicutes) was significantly higher in male than in female spiders (p < .05). The results also showed that amino acid and lipid metabolisms were significantly higher in female than in male spiders (p < .05), whereas glycan biosynthesis and metabolism were significantly higher in male than in female spiders (p < .05). Our results imply that sexual variation is a crucial factor in shaping gut bacterial community in P. astrigera spiders, while the distinct differences of bacterial composition are mainly due to their different nutritional and energy requirements.  相似文献   

6.
Species that inhabit high‐shore environments on rocky shores survive prolonged periods of emersion and thermal stress. Using two Hong Kong high‐shore littorinids (Echinolittorina malaccana and E. radiata) as models, we examined their behavioral repertoire to survive these variable and extreme conditions. Environmental temperatures ranged from 4°C in the cool season to 55.5°C in the hot season, with strong seasonal and daily fluctuations. In the hot season, both species allocated >35% of their activity budgets to stress‐mitigating thermoregulatory behaviors (e.g. standing, towering) and relatively small proportions to foraging (<20%) and reproduction (<10%). In the assumedly benign cool season, greater proportions (>70%) of activity budgets were allocated to stress mitigation behaviors (crevice occupation, aggregation formation). Both species exhibited multifunctional behaviors that optimized time use during their tidally‐constrained activity window in the hot season. Females mated while foraging when awash by the rising tide, and some males crawled on top of females prior to ceasing movement to form ''towers'', which have both thermoregulatory benefits and reduce searching time for mates during subsequent activity. The function of such behaviors varies in a state‐dependent manner, for example, the function of trail following changes over an activity cycle from mate searching on rising tides, to stress mitigation on falling tides (aiding aggregation formation), and to both functions through tower formation just before movement stops. Many of these behavioral responses are, therefore, multifunctional and can vary according to local conditions, allowing snails in this family to successfully colonize the extreme high‐shore environment.  相似文献   

7.
In many insect taxa, there is a well‐established trade‐off between flight capability and reproduction. The wing types of Acridoidea exhibit extremely variability from full length to complete loss in many groups, thus, provide a good model for studying the trade‐off between flight and reproduction. In this study, we completed the sampling of 63 Acridoidea species, measured the body length, wing length, body weight, flight muscle weight, testis and ovary weight, and the relative wing length (RWL), relative flight muscle weight (RFW), and gonadosomatic index (GSI) of different species were statistically analyzed. The results showed that there were significant differences in RWL, RFW, and GSI among Acridoidea species with different wing types. RFW of long‐winged species was significantly higher than that of short‐winged and wingless species (p < .01), while GSI of wingless species was higher than that of long‐winged and short‐winged species. The RWL and RFW had a strong positive correlation in species with different wing types (correlation coefficient r = .8344 for male and .7269 for female, and p < .05), while RFW was strong negatively correlated with GSI (r = −.2649 for male and −.5024 for female, and p < .05). For Acridoidea species with wing dimorphism, males with relatively long wings had higher RFW than that of females with relatively short wings, while females had higher GSI. Phylogenetic comparative analysis showed that RWL, RFW, and GSI all had phylogenetic signals and phylogenetic dependence. These results revealed that long‐winged individuals are flight capable at the expense of reproduction, while short‐winged and wingless individuals cannot fly, but has greater reproductive output. The results support the trade‐off between flight and reproduction in Acridoidea.  相似文献   

8.
Habitat loss is the most prevalent threat to biodiversity in North America. One of the most threatened landscapes in the United States is the sagebrush (Artemisia spp.) ecosystem, much of which has been fragmented or converted to non‐native grasslands via the cheatgrass‐fire cycle. Like many sagebrush obligates, greater sage‐grouse (Centrocercus urophasianus) depend upon sagebrush for food and cover and are affected by changes to this ecosystem. We investigated habitat selection by 28 male greater sage‐grouse during each of 3 years after a 113,000‐ha wildfire in a sagebrush steppe ecosystem in Idaho and Oregon. During the study period, seeding and herbicide treatments were applied for habitat restoration. We evaluated sage‐grouse responses to vegetation and post‐fire restoration treatments. Throughout the 3 years post‐fire, sage‐grouse avoided areas with high exotic annual grass cover but selected strongly for recovering sagebrush and moderately strongly for perennial grasses. By the third year post‐fire, they preferred high‐density sagebrush, especially in winter when sagebrush is the primary component of the sage‐grouse diet. Sage‐grouse preferred forb habitat immediately post‐fire, especially in summer, but this selection preference was less strong in later years. They also selected areas that were intensively treated with herbicide and seeded with sagebrush, grasses, and forbs, although these responses varied with time since treatment. Wildfire can have severe consequences for sagebrush‐obligate species due to loss of large sagebrush plants used for food and for protection from predators and thermal extremes. Our results show that management efforts, including herbicide application and seeding of plants, directed at controlling exotic annual grasses after a wildfire can positively affect habitat selection by sage‐grouse.  相似文献   

9.
Obesity is a significant risk factor for atrial fibrillation (AF), which is the most common sustained arrhythmia with increased mortality and morbidity. High‐fat diet (HFD)‐induced obesity is associated with the activation of endoplasmic reticulum stress (ERS). However, the role of ERS in HFD‐induced AF remains elusive. Human atrium samples were examined for the ERS activation test. C57BL/6J mice were divided into four groups, including the control group, the HFD group, the 4‐phenylbutyric acid (4‐PBA) group, and the HFD + 4‐PBA group. At the age of 4 weeks, the HFD group and the HFD + 4‐PBA group were given HFD to construct the obesity model, while the other two groups were given a normal diet (ND). Transesophageal programmed electrical stimulation was conducted to evaluate the AF inducibility and duration. Atrial fibrosis and ERS activation were also investigated.We found that CHOP and GRP‐78 protein were significantly higher in overweight patients than the controls (both P < 0.05). AF inducibility and duration of the HFD group were significantly higher than the other groups (both P < 0.05), while there was no difference between those groups (P > 0.05). The mice of the HFD group had significantly higher collagen volume fraction (CVF%) than the other groups (P < 0.05). ERS marker protein of GRP78, p‐PERK, ATF6 and CHOP protein expression level was increased in the HFD group, which were significantly mitigated in the HFD + 4‐PBA group. In summary, HFD‐induced ERS activation facilitates atrial fibrosis and AF. The inhibition of ERS might alleviate atrial fibrosis and reduce the incidence of AF‐associated obesity.  相似文献   

10.
《Aging cell》2022,21(6)
DNA methylation (DNAm) has been reported to be associated with many diseases and with mortality. We hypothesized that the integration of DNAm with clinical risk factors would improve mortality prediction. We performed an epigenome‐wide association study of whole blood DNAm in relation to mortality in 15 cohorts (= 15,013). During a mean follow‐up of 10 years, there were 4314 deaths from all causes including 1235 cardiovascular disease (CVD) deaths and 868 cancer deaths. Ancestry‐stratified meta‐analysis of all‐cause mortality identified 163 CpGs in European ancestry (EA) and 17 in African ancestry (AA) participants at < 1 × 10−7, of which 41 (EA) and 16 (AA) were also associated with CVD death, and 15 (EA) and 9 (AA) with cancer death. We built DNAm‐based prediction models for all‐cause mortality that predicted mortality risk after adjusting for clinical risk factors. The mortality prediction model trained by integrating DNAm with clinical risk factors showed an improvement in prediction of cancer death with 5% increase in the C‐index in a replication cohort, compared with the model including clinical risk factors alone. Mendelian randomization identified 15 putatively causal CpGs in relation to longevity, CVD, or cancer risk. For example, cg06885782 (in KCNQ4) was positively associated with risk for prostate cancer (Beta = 1.2, P MR = 4.1 × 10−4) and negatively associated with longevity (Beta = −1.9, P MR = 0.02). Pathway analysis revealed that genes associated with mortality‐related CpGs are enriched for immune‐ and cancer‐related pathways. We identified replicable DNAm signatures of mortality and demonstrated the potential utility of CpGs as informative biomarkers for prediction of mortality risk.  相似文献   

11.
Intramyocellular lipid (IMCL) utilization is impaired in older individuals, and IMCL accumulation is associated with insulin resistance. We hypothesized that increasing muscle total carnitine content in older men would increase fat oxidation and IMCL utilization during exercise, and improve insulin sensitivity. Fourteen healthy older men (69 ± 1 year, BMI 26.5 ± 0.8 kg/m2) performed 1 h of cycling at 50% VO2max and, on a separate occasion, underwent a 60 mU/m2/min euglycaemic hyperinsulinaemic clamp before and after 25 weeks of daily ingestion of a 220 ml insulinogenic beverage (44.4 g carbohydrate, 13.8 g protein) containing 4.5 g placebo (n = 7) or L‐carnitine L‐tartrate (n = 7). During supplementation, participants performed twice‐weekly cycling for 1 h at 50% VO2max. Placebo ingestion had no effect on muscle carnitine content or total fat oxidation during exercise at 50% VO2max. L‐carnitine supplementation resulted in a 20% increase in muscle total carnitine content (20.1 ± 1.2 to 23.9 ± 1.7 mmol/kg/dm; p < 0.01) and a 20% increase in total fat oxidation (181.1 ± 15.0 to 220.4 ± 19.6 J/kg lbm/min; p < 0.01), predominantly due to increased IMCL utilization. These changes were associated with increased expression of genes involved in fat metabolism (ACAT1, DGKD & PLIN2; p < 0.05). There was no change in resting insulin‐stimulated whole‐body or skeletal muscle glucose disposal after supplementation. This is the first study to demonstrate that a carnitine‐mediated increase in fat oxidation is achievable in older individuals. This warrants further investigation given reduced lipid turnover is associated with poor metabolic health in older adults.  相似文献   

12.
In view of the sex differences in aging‐related diseases, sex chromosomes may play a critical role during aging process. This study aimed to identify age‐related DNA methylation changes on Y chromosome (ChrY). A two‐stage study design was conducted in this study. The discovery stage contained 419 Chinese males, including 205 from the Wuhan‐Zhuhai cohort panel, 107 from the coke oven workers panel, and 107 from the Shiyan panel. The validation stage contained 587 Chinese males from the Dongfeng‐Tongji sub‐cohort. We used the Illumina HumanMethylation BeadChip to determine genome‐wide DNA methylation in peripheral blood of the study participants. The associations between age and methylation levels of ChrY CpGs were investigated by using linear regression models with adjustment for potential confounders. Further, associations of age‐related ChrY CpGs with all‐cause mortality were tested in the validation stage. We identified the significant associations of 41 ChrY CpGs with age at false discovery rate (FDR) <0.05 in the discovery stage, and 18 of them were validated in the validation stage (p < 0.05). Meta‐analysis of both stages confirmed the robust positive associations of 14 CpGs and negative associations of 4 CpGs with age (FDR<0.05). Among them, cg03441493 and cg17816615 were significantly associated with all‐cause mortality risk [HR(95% CI) = 1.37 (1.04, 1.79) and 0.70 (0.54, 0.93), respectively]. Our results highlighted the importance of ChrY CpGs on male aging.  相似文献   

13.

The authors note that P values presented in the original Fig 1A and Appendix Fig S1A were not assessed using a proper statistical analysis method. In contrast to the initially employed two‐group t‐test, a one‐sample one‐tailed t‐test is appropriate here, as the basic null hypothesis is that the proportion of MT FOXL2 mRNA in each AGCT patient is lower than WT {H 0: WT(%) > MT(%) }. New p values are presented in the corrected Fig 1A and Appendix Fig S1A, which are P < 0.00001 and P < 0.05, respectively. These revised P values did not affect the conclusion drawn.  相似文献   

14.
The bulbs of common camas (Camassia quamash) were a staple food of Indigenous Peoples of western North America for millennia. Camas harvesting site productivity was encouraged through intense management. Common camas is considered a facultative wetland species, and populations have declined due to contemporary wetland drainage and land conversion. Conservation of existing habitat, as well as restoration of degraded systems, is necessary. Traditional ecological knowledge (TEK) and resource management (TRM) are often promoted as viable modes of contemporary resource management but are rarely tested or implemented. We designed a controlled experiment, informed by a born‐in‐the‐tradition specialist, to evaluate the response of common camas populations to traditional bulb harvest, burning, and a combination of harvest and burning. We recorded camas plant counts of three life stage classes of camas plants (single‐leaf seedling, multiple‐leaf adult, and flowering adult) over the course of 6 years in arrays of plots and subjected to treatments or left undisturbed as control. Harvesting removed plants (>800 bulbs) and reduced aboveground counts of camas densities (X¯ ~ 50% of control, p < .05). Burning contributed to a reduction in single‐leaf plants but had an overall positive effect (X¯ ~ 150% of control, p < .05) on adult camas and flowering plant abundance, and ameliorated the digging impacts. Treatment impacts tapered over the course of the study, and results indicate that a sustainable harvesting return interval of approximately 5 years may be possible when combined with fire to reduce litter and competition from pasture grasses and to accelerate the recovery of camas. Our findings support the hypotheses proposed by traditional knowledge specialists and ethnobotanists that digging and burning reduce intra‐ and interspecific competition and stimulate the growth of unharvested adult plants. More generally, our study supports the integration of traditional ecological knowledge into the evidence base available for protected area wetland prairie management.  相似文献   

15.
Qualitative and quantitative assessment of heavy metals in the Thermal Power Plant effluent was performed to study the impact of their toxic effects on various biomarkers (carbohydrate, protein and lipid profiles). Heavy metals present in the water were in the order Fe > Cu > Zn > Mn > Ni > Co > Cr. Fe and Ni exceeded and Cr was equal to the USA standards set by UNEPGEMS. Glycogen in liver (p < 0.001) and muscle (p < 0.01) depleted significantly. Insignificant (p < 0.05) decline in blood glucose (−21.0%) and significant (p < 0.05) elevation in both total protein and globulin in serum, liver and muscle was noted. Albumin decreased significantly (p < 0.01) in serum but showed significant (p < 0.05) increase in liver and muscle. Thus A:G ratio fell in serum and rose in liver and muscle. Similarly lipid profile also gets altered where significant elevation in serum total lipid (p < 0.01), total cholesterol (p < 0.01), phospholipid (p < 0.05), triglycerides (p < 0.001), LDL (p < 0.01) was observed but significant (p < 0.05) decline in VLDL was recorded. These biomarkers suggested that fish become hypoglycemic, hyperlipidemic and hypercholesterolemic. Heavy metals also provoked immune response as evident from the rise in globulin. In conclusion the Thermal Power Plant wastewater containing heavy metals induced stress, making fish weak and vulnerable to diseases.  相似文献   

16.
Ischaemia/reperfusion (I/R)‐induced hepatic injury is regarded as a main reason of hepatic failure after transplantation or lobectomy. The current study aimed to investigate how the opioid analgesic remifentanil treatment affects I/R‐induced hepatic injury and explore the possible mechanisms related to HIF1α. Initially, an I/R‐induced hepatic injury animal model was established in C57BL/6 mice, and an in vitro hypoxia‐reoxygenation model was constructed in NCTC‐1469 cells, followed by remifentanil treatment and HIF1α silencing treatment. The levels of blood glucose, lipids, alanine transaminase (ALT) and aspartate transaminase (AST) in mouse serum were measured using automatic chemistry analyser, while the viability and apoptosis of cells were detected using CCK8 assay and flow cytometry. Our results revealed that mice with I/R‐induced hepatic injury showed higher serum levels of blood glucose, lipids, ALT and AST and leukaemia inhibitory factor (LIF) expression, and lower HIF1α and ZEB1 expression (P < .05), which were reversed after remifentanil treatment (P < .05). Besides, HIF1α silencing increased the serum levels of blood glucose, lipids, ALT and AST (P < .05). Furthermore, hypoxia‐induced NCTC‐1469 cells exhibited decreased HIF1α and ZEB1 expression, reduced cell viability, as well as increased LIF expression and cell apoptosis (P < .05), which were reversed by remifentanil treatment (P < .05). Moreover, HIF1α silencing down‐regulated ZEB1 expression, decreased cell viability, and increased cell apoptosis (P < .05). ZEB1 was identified to bind to the promoter region of LIF and inhibit its expression. In summary, remifentanil protects against hepatic I/R injury through HIF1α and downstream effectors.  相似文献   

17.
In genetically heterogeneous mice produced by the CByB6F1 x C3D2F1 cross, the “non‐feminizing” estrogen, 17‐α‐estradiol (17aE2), extended median male lifespan by 19% (p < 0.0001, log‐rank test) and 11% (p = 0.007) when fed at 14.4 ppm starting at 16 and 20 months, respectively. 90th percentile lifespans were extended 7% (p = 0.004, Wang–Allison test) and 5% (p = 0.17). Body weights were reduced about 20% after starting the 17aE2 diets. Four other interventions were tested in males and females: nicotinamide riboside, candesartan cilexetil, geranylgeranylacetone, and MIF098. Despite some data suggesting that nicotinamide riboside would be effective, neither it nor the other three increased lifespans significantly at the doses tested. The 17aE2 results confirm and extend our original reports, with very similar results when started at 16 months compared with mice started at 10 months of age in a prior study. The consistently large lifespan benefit in males, even when treatment is started late in life, may provide information on sex‐specific aspects of aging.  相似文献   

18.
Accurate measurements of cellular protein concentrations are invaluable to quantitative studies of gene expression and physiology in living cells. Here, we developed a versatile mass spectrometric workflow based on data‐independent acquisition proteomics (DIA/SWATH) together with a novel protein inference algorithm (xTop). We used this workflow to accurately quantify absolute protein abundances in Escherichia coli for > 2,000 proteins over > 60 growth conditions, including nutrient limitations, non‐metabolic stresses, and non‐planktonic states. The resulting high‐quality dataset of protein mass fractions allowed us to characterize proteome responses from a coarse (groups of related proteins) to a fine (individual) protein level. Hereby, a plethora of novel biological findings could be elucidated, including the generic upregulation of low‐abundant proteins under various metabolic limitations, the non‐specificity of catabolic enzymes upregulated under carbon limitation, the lack of large‐scale proteome reallocation under stress compared to nutrient limitations, as well as surprising strain‐dependent effects important for biofilm formation. These results present valuable resources for the systems biology community and can be used for future multi‐omics studies of gene regulation and metabolic control in Ecoli.  相似文献   

19.
Lacking systematic evaluations in soil quality and microbial community recovery after different amendments addition limits optimization of amendments combination in coal mine soils. We performed a short‐term incubation experiment with a varying temperature over 12 weeks to assess the effects of three amendments (biochar: C; nitrogen fertilizer at three levels: N‐N1~N3; microbial agent at two levels: M‐M1~M2) based on C/N ratio (regulated by biochar and N level: 35:1, 25:1, 12.5:1) on mine soil properties and microbial community in the Qilian Mountains, China. Over the incubation period, soil pH and MBC/MBN were significantly lower than unamended treatment in N addition and C + M + N treatments, respectively. Soil organic carbon (SOC), total nitrogen (TN), available nitrogen (AN), available phosphorus (AP), available potassium (AK), microbial biomass carbon (MBC), and nitrogen (MBN) contents increased significantly in all amended treatments (p < .001). Higher AP, AK, MBC, MBN, and lower MBC/MBN were observed in N2‐treated soil (corresponding to C/N ratio of 25:1). Meanwhile, N2‐treated soil significantly increased species richness and diversity of soil bacterial community (p < .05). Principal coordinate analysis further showed that soil bacterial community compositions were significantly separated by N level. C‐M‐N treatments significantly increased the relative abundance (>1%) of the bacterial phyla Bacteroidetes and Firmicutes, and decreased the relative abundance of fungal phyla Chytridiomycota (p < .05). Redundancy analysis illustrated the importance of soil nutrients in explaining variability in bacterial community composition (74.73%) than fungal composition (35.0%). Our results indicated that N addition based on biochar and M can improve soil quality by neutralizing soil pH and increasing soil nutrient contents in short‐term, and the appropriate C/N ratio (25:1) can better promote microbial mass, richness, and diversity of soil bacterial community. Our study provided a new insight for achieving restoration of damaged habitats by changing microbial structure, diversity, and mass by regulating C/N ratio of amendments.  相似文献   

20.
Atrial fibrillation (AF) is associated with short-term mortality after ST-elevation myocardial infarction (STEMI), but there is limited data on the temporal association between AF and mortality after STEMI. A total of 830 patients were included (age: 62 ± 12 years, 76 % male). Patients with new-onset AF < 30 days after STEMI were divided among three subgroups: AF on the day of admission, AF 24–72 h and AF > 72 h after admission. Thirty-day mortality was assessed by telephone and via the municipal population registry. Twenty patients died < 30 days after admission. In 41 patients, AF was detected on the day of admission, in 14 patients 24–72 h after admission and in 18 patients > 72 h after admission. Mortality was higher in patients with AF on the day of admission (7.3 vs 2.2 %, p = 0.036) and 24–72 h after admission (14.3 vs 1.4 %, p < 0.001), but not in patients with AF > 72 h after admission (0 vs 1.1 %, p > 0.999). Age (odds ratio (OR) 1.123, p < 0.001), Killip class (adjusted OR 8.341, p < 0.001), AF on the day of admission (OR 3.585, p = 0.049) and 24–72 h after admission (OR 11.515, p = 0.003) were, amongst other variables, associated with an increased 30-day mortality. In conclusion, only new-onset incident AF during the first 72 h after admission was associated with 30-day mortality in STEMI patients.

Electronic supplementary material

The online version of this article (doi:10.1007/s12471-015-0709-2) contains supplementary material, which is available to authorized users.  相似文献   

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