•Rising temperature accelerated the mineralization of SOC in permafrost peatlands.•Q10 of SOC mineralization ranged from 2.24 to 4.22 among 7 permafrost peatlands.•SOC mineralization positively ...correlated with soil DOC, NH4+-N, NO3−-N contents.•Substrate availability and microbe drive SOC mineralization in permafrost peatlands.
Permafrost peatlands are important pools of soil carbon. Soil organic carbon (SOC) mineralization and its temperature sensitivity in permafrost peatlands are crucial for predictions of soil carbon-climate feedback. However, little is known about the changes in SOC mineralization and its mechanism in response to environmental change in the permafrost peatlands of Northeastern China. We collected seven permafrost peatland soils from Greater and Lesser Khingan Mountains in Northeastern China to investigate how the responses of microbes and labile substrates control the mineralization of SOC in the laboratory incubation study. The results show that temperature and sampling sites affected the mineralization of SOC. Elevated temperatures significantly increased the rate of carbon mineralization across the peatland soils. The mean sensitivity of SOC mineralization to temperature (Q10 value) was 2.96. The increase in substrate availability and microbial abundance in parallel with the increase in temperature is responsible for the high rates of decomposition of the organic carbon pools. We found that the mineralization of soil carbon positively correlated with the concentrations of soil dissolved organic carbon (DOC), NH4+-N, NO3−-N, as well as the abundances of bacteria, fungi, methanotrophs and nirK denitrifiers. Moreover, the content of DOC positively correlated with the abundances of soil bacteria, methanotrophs and nirK denitrifiers, indicating that the influences of soil microbial abundances on carbon mineralization were strongly mediated by the availability of carbon substrates. Our findings provide novel insights into the effects of increasing temperatures on the relationship between microbial communities and labile substrates and their roles in carbon decomposition in permafrost peatlands.
•The decomposition of E. vaginatum litter is faster than that of Sphagnum.•Warming could promote decomposition of E. vaginatum and Sphagnum litter.•N addition promoted the decomposition of Sphagnum ...(low N) and vascular litter.•High N concentration inhibited the decomposition of Sphagnum litter.•Microorganisms regulated warming and N addition impacts on litter decomposition.
As one kind of the most important carbon (C) sink in the world, peatlands are sensitive to climate change. The decomposition of litter plays an important role in C fixation and nutrient utilization in peatlands. To reveal the mechanism of response of the litter decomposition to climate warming and the addition of nitrogen (N) in permafrostpeatlands, we selected two typical plants, Eriophorumvaginatum and Sphagnumpalustre, in the permafrost peatland of Da Xing’anling Mountains, China, as the research objects and conducted a 54-day litter decomposition experiment at 10 ℃ and 20 ℃. Three N addition treatments (CK: 0 mg N g−1, N1: 2.5 mg N g−1, and N2: 5 mg N g−1) were established. Our results showed that the E. vaginatum litter decomposed more quickly than that of Sphagnum, and an increase in temperature significantly promoted the litter decomposition and CO2 emission of E. vaginatum and Sphagnum. The addition of N promoted the decomposition of E. vaginatum litter, whereas the decomposition of Sphagnum litter was promoted by the N1 treatment but was inhibited by the N2 treatment. The enzyme activity in both types of litter was inhibited with the increase in temperature. The abundances of bacteria and fungi positively correlated with the decomposition constant and mean CO2 release rate by E. vaginatum and Sphagnum litter, indicating that the effects of temperature and N addition on the decomposition of plant litter were primarily regulated by microorganisms. This study provides a theoretical basis to understand and predict the effects of global climate change on the decomposition of plant litter in boreal peatlands.
To accurately screen potential immune cells that can predict the survival of colorectal cancer (CRC) patients and identify related prognostic predictors.
The sample data of CRC patients were ...downloaded from the GEO database as a training set to establish a prognosis-scoring model and screen prognosis-related immune cells. The sample data of CRC patients from the TCGA database were used as the validation set. Simultaneously, cancer tissue samples from 116 patients with CRC diagnosed pathologically in Shanghai Dongfang Hospital were collected to analyze the relationship of prognosis-related immune cells with patients' survival, and clinical and pathological parameters, and to screen prognostic predictors.
Prognosis-related immune cells screened from GEO and TCGA databases mainly included Follicular Helper T cells (Tfh), Monocytes and M2 Macrophages. In the training set, the 2,000- and 4,000-day survival rates were 48.3% and 10.7% in the low-risk group (N = 234), and 42.1% and 7.5% in the high-risk group (N = 214), respectively. In the validation set, the 2,000- and 4,000-day survival rates were 34.8% and 8.6% in the low-risk group (N = 187), and 28.9% and 6.1% in the high-risk group (N = 246), respectively. The prognosis of patients in the high-risk group was worse than that in the low-risk group (P < 0.05). Furthermore, the screened primary prognostic predictors were CD163 and CD4 + CXCR5. CD163 protein expression was distributed in Monocytes and M2 Macrophages. The 1,000- and 2,000-day survival rates were 56.1% and 7.0% in the CD163 low-expression group, and 40.7% and 1.7% in the high-expression group (N = 214), respectively, showing a worse prognosis in the high-expression group than that in the low-expression group. Meanwhile, the immune marker CD4 + CXCR5 could identify Tfh. The 1,000- and 2,000-day survival rates were 63.9% and 5.6% in the CD4 + CXCR5 high-expression group, and 33.3% and 2.8% in the low-expression group (N = 214), respectively, with a better prognosis in the high-expression group than that in the low-expression group.
Prognostic-related immune cells of CRC mainly include Tfh cells, Monocytes and M2 Macrophages. Monocytes and M2 Macrophages correlate negatively, while Tfh cells correlate positively with the prognosis of CRC patients. Immune markers CD163 and CD4 + CXCR5 can be considered as the prognostic predictors of CRC with clinical value of the application.
•Warming increases soil C cycling microbial abundance, which will result in C loss.•Soil nifH and nirK gene abundances exhibit insensitivity to 6 years of warming.•Soil β-glucosidase, inverse, and ...urease respond differently to 6 years of warming.•Warming accelerates DOC decomposition and leaching from shrub non-rhizosphere soil.•No warming effect is observed on soil TC, MBC, and NO3−–N content.
Soil microbes and enzymes in permafrost peatland are sensitive to temperature changes, which might result in more potential loss of carbon and increase in available nitrogen from permafrost peatlands in a warming world. We previously demonstrated that 3-year warming could affect soil microbial abundance and enzymatic activity. However, soil microbial abundance and enzymatic activity in permafrost peatlands under long-term climate warming is not well understood. Therefore, a 6-year field manipulation experiment was used to assess the impact of long-term warming on soil microbial abundance and enzymatic activity in a permafrost peatland in northeastern China. Results showed that 6-year warming increased the abundance of bacteria in 0 to 15 cm soil under tussock and from shrub rhizosphere, fungi from shrub non-rhizosphere, and archaea under tussock and from the rhizosphere of shrub. These increased microbial abundances could stimulate soil carbon cycling and accelerate soil carbon loss in permafrost peatland under warming. Six-year warming increased methanogen abundance in 0 to 15 cm soil and methanotroph abundance in 15 to 30 cm soil under tussock, indicating that warming could enhance CH4 cycling. Soil nirS-denitrifier abundance from the 0 to 15 cm shrub rhizosphere increased under warming, thereby suggesting that warming stimulated denitrification and N2O emission. β-Glucosidase activity in 0 to 15 cm soil under tussock and from shrub rhizosphere increased, but invertase activity in 15 to 30 cm soil under tussock and from shrub rhizosphere showed opposite tendency under warming. DOC content tended to increase in the 0 to 15 cm rhizosphere soil, but decreased in shrub non-rhizosphere soil. Warming increased NH4+–N content in both rhizosphere and non-rhizosphere soil. Positive correlations between abundances of bacteria, archaea, contents of DOC, and NH4+–N in 0 to 15 cm soil suggest that increases in bacterial and archaeal abundance could indicate higher carbon and nitrogen availability in topsoil of permafrost peatlands under warming. The results offer new insights into the response of plant–soil-microbe interactions in permafrost peatlands to climate change.
Changes in soil CO
2
and N
2
O emissions due to climate change and nitrogen input will result in increased levels of atmospheric CO
2
and N
2
O, thereby feeding back into Earth’s climate. ...Understanding the responses of soil carbon and nitrogen emissions mediated by microbe from permafrost peatland to temperature rising is important for modeling the regional carbon and nitrogen balance. This study conducted a laboratory incubation experiment at 15 and 20°C to observe the impact of increasing temperature on soil CO
2
and N
2
O emissions and soil microbial abundances in permafrost peatland. An NH
4
NO
3
solution was added to soil at a concentration of 50 mg N kg
−1
to investigate the effect of nitrogen addition. The results indicated that elevated temperature, available nitrogen, and their combined effects significantly increased CO
2
and N
2
O emissions in permafrost peatland. However, the temperature sensitivities of soil CO
2
and N
2
O emissions were not affected by nitrogen addition. Warming significantly increased the abundances of methanogens, methanotrophs, and
nir
K-type denitrifiers, and the contents of soil dissolved organic carbon (DOC) and ammonia nitrogen, whereas
nir
S-type denitrifiers, β-1,4-glucosidase (βG), cellobiohydrolase (CBH), and acid phosphatase (AP) activities significantly decreased. Nitrogen addition significantly increased soil
nir
S-type denitrifiers abundances, β-1,4-N- acetylglucosaminidase (NAG) activities, and ammonia nitrogen and nitrate nitrogen contents, but significantly reduced bacterial, methanogen abundances, CBH, and AP activities. A rising temperature and nitrogen addition had synergistic effects on soil fungal and methanotroph abundances, NAG activities, and DOC and DON contents. Soil CO
2
emissions showed a significantly positive correlation with soil fungal abundances, NAG activities, and ammonia nitrogen and nitrate nitrogen contents. Soil N
2
O emissions showed positive correlations with soil fungal, methanotroph, and
nir
K-type denitrifiers abundances, and DOC, ammonia nitrogen, and nitrate contents. These results demonstrate the importance of soil microbes, labile carbon, and nitrogen for regulating soil carbon and nitrogen emissions. The results of this study can assist simulating the effects of global climate change on carbon and nitrogen cycling in permafrost peatlands.
Malignant melanoma (MM) generally presents as a primary neoplasm of the skin, and most MM cases of the respiratory system are metastatic. Primary MM of the lung (PMML) is quite rare, and its ...diagnosis is relatively difficult.
We report the case of a 57-year-old male patient with PMML who denied any history of tumours. His initial complaint was frequent coughs with bloody sputum for 4 days. Chest radiography demonstrated a high-density shadow in the lower lobe of the right lung, which was suspected to be a large space-occupying lesion on subsequent computed tomography (CT) and to be a hypermetabolic tumour by positron emission tomography-CT. To confirm the diagnosis, exploratory surgery was performed. Finally, we confirmed the diagnosis of PMML.
PMML is extremely rare and easily misdiagnosed as lung cancer. Because of its morphological and immunophenotypic variations, the diagnosis of PMML remains difficult. This case report discusses the diagnosis and case management of a patient while referring to the existing literature.
Gastric cancer (GC) is a cancer with a high mortality rate. lncRNAs play a role in regulating GC tumorigenesis. In this paper, we analyzed differentially expressed lncRNAs between GC and adjacent ...normal tissues using multiple bioinformatics tools to identify new potential targets in GC. Cell viability and migration ability were detected using the Cell Counting Kit-8 (CCK-8) and transwell assays, MIR4435-2HG was negatively correlated with the survival rate of GC patients, and by inhibiting the activity of MIR4435-2HG, the viability and migration ability of GC cells could be reduced. In addition, RT- qPCR and western blot to detect gene and protein level expression, transmission electron microscopy and nanoparticle tracking analysis (NTA) to study the efficiency of exosome isolation, and flow cytometry to observe cell differentiation were employed, delivery of MIR4435-2HG shRNA
MKN45 cell-derived exosomes significantly reversed the MKN45 exosome-induced M2 polarization in macrophages. Furthermore, the low expression of MIR4435-2HG in MKN45 cell-derived exosomes inhibited the Jagged1/Notch and JAK1/STAT3 pathways in macrophages; MIR4435-2HG downregulated exosomes were found to significantly inhibit GC tumor growth
by establishing a mouse model. In short, MKN45 cell-derived exosomes deliver lncRNA MIR4435-2HG, which promotes gastric carcinogenesis by inducing macrophage M2 polarization.
The development of an anti-drug antibody (ADA)-tolerant pharmacokinetic (PK) assay is important when the drug exposure is irrelevant to toxicity in the presence of ADA. We aimed to develop and ...validate an ADA-tolerant assay for an exatecan-based antibody-drug conjugate (ADC) in monkey plasma.
The assay tolerated 5.00 µg/mL of ADA at 12 µg/mL of ADC. Its accuracy and precision results satisfied the acceptance criteria. Furthermore, the assay was free from hook and matrix effects and exhibited good dilutional linearity. Additionally, the ADC in plasma samples was stable under different storage conditions.
An ADA-tolerant ADC assay was configured with an anti-payload antibody for capture, and a drug-target protein combined with a horseradish peroxidase (HRP)-labeled antibody against a drug-target-protein tag for detection. Samples were firstly acidified to dissociate drug and ADA complexes, and to convert the carboxylate form to the lactone form of exatecan molecules; then, the ADAs in the samples were removed with a naked antibody-coated microplate. The treated samples were further incubated with coated anti-payload antibody and captured ADC molecules were quantified by the detection reagent. The developed assay was optimized and validated against regulatory guidelines.
The assay met both methodological and sample-related ADA tolerance requirements, and was applicable to a nonclinical study in cynomolgus monkeys.
The rhizosphere microenvironment is crucial to plant–soil physiological processes. The differences among microbial communities in the rhizosphere and non-rhizosphere peatland topsoil (0–15 cm) and ...subsoil (15–30 cm) in five plant communities dominated by Carex schmidtii, Chamaedaphne calyculata, Ledum palustre, Betula fruticosa, and Vaccinium uliginosum, as well as non-rhizosphere soil in discontinuous and continuous permafrost regions, were studied. We found that the bacteria and nifH gene abundances in the C. calyculata rhizosphere soil in the discontinuous permafrost region were higher than those in continuous permafrost region, while the nirK and nifH gene abundances in the non-rhizosphere soil of the discontinuous permafrost region were lower than those in the continuous permafrost region. The ratio of bacteria to fungi decreased and that of nirK to nirS increased significantly from the discontinuous to the continuous permafrost region, indicating that permafrost degradation can change soil microbial community composition. Fungal abundance was higher in the rhizosphere than the non-rhizosphere soils, suggesting that plant roots provide a more suitable environment for fungi. Moreover, the abundances of the topsoil bacteria; the fungi; and the nirK, nirS, and nifH genes were higher than those in the subsoil because of the organic matter from plant litter as a source of nutrients. The microbial abundance in the subsoil was also more affected by nutrient availability. To sum up, the microbial abundance varied among the different types of rhizosphere and non-rhizosphere soils, and the carbon and nitrogen cycling processes mediated by soil microorganisms may be greatly altered due to permafrost degradation under climate warming.
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