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The priming effects (PEs) of soil organic carbon (SOC) decomposition is a crucial process affecting the C balance of terrestrial ecosystems. However, there is uncertainty about how PEs will respond to climate warming. In this study, we sampled soils along a subtropical elevation gradient in China and conducted a 126‐day lab‐incubation experiment with and without the addition of 13C‐labeled high‐bioavailability glucose or low‐bioavailability lignin. Based on the mean annual temperature (MAT) of each elevation (9.3–16.4°C), a temperature increase of 4°C was used to explore how PEs mediate the decomposition of SOC in response to warming. Our results showed that the magnitude of glucose‐induced PEs (PEglucose) was higher than lignin‐induced PEs (PElignin), with both PEs linearly increasing with MAT. Across the MAT (i.e., elevation) gradient, short‐term warming had a constant magnitude of negative effects on PEglucose, whereas rising MAT exacerbated the negative effects of short‐term warming on PElignin. Moreover, the temperature sensitivity of SOC decomposition decreased after adding glucose and lignin across the MAT gradient, suggesting that fresh C inputs may prime the microbial breakdown of labile SOC under warming. Taken together, warming alleviated SOC loss due to PEs through varying mechanisms depending on substrate bioavailability. Warming mediated the PEglucose by increasing available nitrogen and weakening microbial nitrogen‐mining but inhibited the PElignin by shifting from microbial nitrogen‐mining to microbial co‐metabolization. Our findings highlight the role of warming in regulating the PEs and suggest that incorporating the suppression effect of warming on PEs can contribute to the accurate prediction of soil C dynamics in a warming world. Plain Language Summary: Tropical and subtropical ecosystems have the highest vegetation productivity and diversity on earth and play a crucial role in regulating climate change. However, it is unclear how diverse plant‐derived components stimulate microbial decomposition of soil organic carbon (SOC) via a phenomenon called priming effects (PEs) under climate warming. Here, we added two 13C‐labeled substitutions of plant components (e.g., glucose and lignin) to soils collected from a subtropical elevation gradient and carried out a 126‐day lab‐incubation experiment. Warming consistently harmed glucose‐induced PEs (PEglucose), while amplified the negative effect on lignin‐induced PEs (PElignin) across the elevation gradient, suggesting that warming has stronger negative effects on PElignin at warmer sites. Warming mediates the PEglucose by weakening microbial N‐mining but strengthening microbial preferential substrate utilization. This is achieved by reducing substrate‐built microbial biomass and making more substrate for respiration compared to unwarmed soil. In contrast, warming inhibits lignin‐induced PEs by shifting from microbial N‐mining to microbial co‐metabolization. This shift is supported by the positive association between lignin‐induced PEs and lignin‐derived microbial biomass and available nitrogen. Our measurement suggests that warming decreased the intensity of SOC decomposition by downregulating the primed SOC loss with fresh substrate inputs through varying mechanisms depending on substrate bioavailability. Key Points: Soil C priming effect linearly decreases with elevation in subtropicsHigh‐ and low‐quality substrates play opposite but complementary roles in soil C feedback to climate warmingThe suppression effect of warming on priming can contribute to the accurate prediction of soil C dynamics in a warmer world [ABSTRACT FROM AUTHOR]

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Background: The rising cancer incidence in patients with oral leukoplakia (OL) highlights the importance of identifying potential biomarkers for high‐risk individuals and lesions because these biomarkers are useful in developing personalized management strategies for OL patients. This study systematically searched and analyzed the literature on potential saliva and serum biomarkers for OL malignant transformation. Methods: PubMed and Scopus were searched for studies published up to April 2022. The primary outcome of this study was the difference in biomarker concentrations in saliva or serum samples from healthy control (HC), OL and oral cancer (OC) populations. Cohen's d with 95% credible interval was calculated and pooled using the inverse variance heterogeneity method. Results: A total of seven saliva biomarkers were analyzed in this paper, including interleukin‐1alpha, interleukin‐6 (IL‐6), interleukin‐6‐8, tumor necrosis factor alpha (TNF‐α), copper, zinc, and lactate dehydrogenase. IL‐6 and TNF‐α exhibited statistically significant deviations in comparisons between HC versus OL and OL versus OC. A total of 13 serum biomarkers were analyzed, including IL‐6, TNF‐α, C‐reactive protein, total cholesterol, triglycerides, high‐density lipoproteins, low‐density lipoproteins, albumin, protein, β2‐microglobulin, fucose, lipid‐bound sialic acid (LSA), and total sialic acid (TSA). LSA and TSA exhibited statistically significant deviations in comparisons between HC versus OL and OL versus OC. Conclusion: IL‐6 and TNF‐α in saliva have strong predictive values for OL deterioration, and LSA and TSA concentration levels in serum also have the potential to serve as biomarkers for OL deterioration. [ABSTRACT FROM AUTHOR]

Summary: Soil organic carbon (SOC) is a mixture of various carbon (C) compounds with different stability, which can be distinctly affected by the priming effect (PE). However, little is known about how the PE changes with SOC stability.We address this issue by combining results from two experiments and a metaanalysis.We found that the PE increased with the prolongation of soil preincubation, suggesting that higher PE occurred for more stable SOC than for labile SOC. This was further supported by the metaanalysis of 42 observations. There were significant negative relationships between the difference in PE (ΔPE) between labile and more stable SOC and their differences in SOC, microbial biomass C and soil C : N ratio, indicating that soil C availability exerts a vital control on ΔPE.We conclude that, compared with labile SOC, stable SOC can be more vulnerable to priming once microbes are provided with exogenous C substrates. This high vulnerability of stable SOC to priming warrants more attention in future studies on SOC cycling and global change. [ABSTRACT FROM AUTHOR]

Single and mixed vegetation types have significant effects on soil parameters and the composition and diversity of soil bacterial community. To understand the influence of different vegetation types on the structure of soil bacterial community across soil depth in a subtropical forest, we assessed the relative abundance of edaphic bacterial community and soil parameters, including pH, cation exchange capacity (CEC), and dissolved organic C in Daiyun Mountain Nature Reserve in Fujian Province, southeastern China. The study area constitutes pine coniferous forest (CF) of Pinus taiwanensis Hayata, broad‐leaved forest (BF) of Castanopsis fabri Hance, and a mixed forest comprising CF and BF (MF). Quantitative polymerase chain reaction (PCR) and Illumina sequencing of 16S ribosomal DNA were used to analyze the abundance, diversity, and composition of soil bacteria. The results showed that the pH, CEC, and diversity of tree species are all associated with the composition of bacterial community in the soil. It was found that CEC, soluble organic N, and pH largely affected the structure of soil bacterial community in A horizon, whereas CEC, moisture content, and organic P affected the structure of soil bacterial community in B horizon. We found that the dominant taxa in the CF and BF were Proteobacteria and Acidobacteria, respectively. The results of both mental and random forest analyses displayed groups according to vegetation types, indicating that the bacterial communities in the research site were significantly influenced by vegetation types in subtropical forests. The study highlights the ecological effects of forest management and elucidates the differences in the functional structure of soil bacterial communities under different vegetation types and soil depths. Core Ideas: Broad‐leaved forests have the highest soil nutrient content in subtropical forests.Acidobacteria and Proteobacteria are biomarker phyla in subtropical forests.Vegetation type affects soil bacterial community structure in subtropical forests.Soil moisture content and organic P affect bacterial community composition in the A horizon.Cation exchange capacity and pH affect bacterial community composition in the B horizon. [ABSTRACT FROM AUTHOR]

Dietary chia seed (Salvia hispanica L.) has significant health‐related benefits due to its high nutrient contents. However, few studies reported the fate of whole seeds in the gastrointestinal tract. Herein, we explored the digestive characteristics in terms of hydrolysis of nutrients, structural and functional properties with a static in vitro digestion method. After gastrointestinal digestion, the digestibility of lipid and protein was 0.46% and 11.38%, respectively. The release rates of tryptophan, tyrosine and lysine were greater than 20%, whereas the glutamic acid and aspartic acid were less than 5%. The microscopic results (optical microscopy (OM), laser scanning confocal microscopy (LSCM) and scanning electron microscopy (SEM)) demonstrated that the seeds remained intact, and the mucilage adhered tightly to the seed coat during digestion. The water holding capacity and oil holding capacity of seeds accounted for 6.37 and 3.28 g/g after intestinal digestion, which were significantly lower than gastric digestion endpoints (P < 0.05). And there were no significant differences in Fourier transform infrared spectroscopy of G‐Mucilage and I‐Mucilage. In general, preprocessing before being consumed is necessary for chia seeds to take full advantage of rich polyunsaturated fatty acids and proteins. [ABSTRACT FROM AUTHOR]

Global changes can alter plant inputs from both above‐ and belowground, which, thus, may differently affect soil carbon and microbial communities. However, the general patterns of how plant input changes affect them in forests remain unclear. By conducting a meta‐analysis of 3193 observations from 166 experiments worldwide, we found that alterations in aboveground litter and/or root inputs had profound effects on soil carbon and microbial communities in forest ecosystems. Litter addition stimulated soil organic carbon (SOC) pools and microbial biomass, whereas removal of litter, roots or both (no inputs) decreased them. The increased SOC under litter addition suggested that aboveground litter inputs benefit SOC sequestration despite accelerated decomposition. Unlike root removal, litter alterations and no inputs altered particulate organic carbon, whereas all detrital treatments did not significantly change mineral‐associated organic carbon. In addition, detrital treatments contrastingly altered soil microbial community, with litter addition or removal shifting it toward fungi, whereas root removal shifting it toward bacteria. Furthermore, the responses of soil carbon and microbial biomass to litter alterations positively correlated with litter input rate and total litter input, suggesting that litter input quantity is a critical controller of belowground processes. Taken together, these findings provide critical insights into understanding how altered plant productivity and allocation affects soil carbon cycling, microbial communities and functioning of forest ecosystems under global changes. Future studies can take full advantage of the existing plant detritus experiments and should focus on the relative roles of litter and roots in forming SOC and its fractions. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective To report the performance of massively parallel sequencing (MPS) based prenatal noninvasive fetal trisomy test based on cell-free DNA sequencing from maternal plasma in a routine clinical setting in China. Method The MPS-based test was offered as a prenatal screening test for trisomies 21 and 18 to pregnant women in 49 medical centers over 2 years. A total of 11 263 participants were recruited and the MPS-based test was performed in 11 105 pregnancies. Fetal outcome data were obtained after the expected date of confinement. Results One hundred ninety cases were classified as positive, including 143 cases of trisomy 21 and 47 cases of trisomy 18. With the karyotyping results and the feedback of fetal outcome data, we observed one false positive case of trisomy 21, one false positive case of trisomy 18 and no false negative cases, indicating 100% sensitivity and 99.96% specificity for the detection of trisomies 21 and 18. Conclusion Our large-scale multicenter study proved that the MPS-based test is of high sensitivity and specificity in detecting fetal trisomies 21 and 18. The introduction of this screening test into a routine clinical setting could avoid about 98% of invasive prenatal diagnostic procedures. © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background and Purpose: Considerable evidence indicates that the beta(2)-adrenoceptor agonist clenbuterol decreases apoptosis in a rodent model of ischaemic cardiomyopathy. In this study, we investigated the effects of clenbuterol on infarct size caused by myocardial ischaemia/reperfusion (I/R) in anaesthetized rats.Experimental Approach: Rats were randomly assigned to the following groups: (i) sham (ii) I/R (iii) clenbuterol + I/R (iv) ICI 118551 + clenbuterol + I/R (v) metoprolol + clenbuterol + I/R (vi) metoprolol + I/R (vii) pertussis toxin + clenbuterol + I/R. Under anaesthesia, left anterior descending coronary artery was occluded for 30 min followed by reperfusion for 2 h.Key Results: Compared with the control I/R group,the clenbuterol (0.5 mg.kg(-1), i.p.) group had reduced infarct size, improved diastolic function and sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA) activity, increased superoxide dismutase activity, and decreased malondialdehyde (MDA) level and LDH, CK release. Clenbuterol increased the phosphorylation of ERK1/2, which resulted in inhibition of myocardial apoptosis as indicated by the reduction of terminal deoxynucleotidyltransferase end labelling-positive staining, Bax/Bcl-2 mRNA and caspase-3 protein expression. The G(i)-protein inhibitor pertussis toxin blocked the clenbuterol-induced improvement in cardiac function and infarct size. Pretreatment with ICI 118551(a selective beta(2)-adrenoceptor antagonist) inhibited the effects of clenbuterol mentioned above. The beta(1)-adrenoceptor agonist metoprolol had similar effects to clenbuterol but failed to reduce MDA and improve SERCA activity. When administered together, metoprolol and clenbuterol did not induce synergistic effects.Conclusions and Implications: Clenbuterol pretreatment provides significant cardioprotection against ischaemia/reperfusion injury and this is mediated by the beta(2)-adrenoceptor-G(i)-protein signalling. A combination of the beta(2)-adrenoceptor agonist clenbuterol and the beta(1)-antagonist metoprolol did not lead to a synergistic anti-apoptotic effect. [ABSTRACT FROM AUTHOR]