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Chimeric antigen receptor (CAR)-modified T and NK cell immunotherapy is a promising approach for cancer treatment. Due to the lack of tunability in anti-tumor activity, conventional CAR therapies have limited efficacy at low tumor antigen densities. To tune the CAR response to tumor cell surface antigens, we have developed a split CAR using the SpyCatcher-SpyTag system. The SpyCatcher serves as the ectodomain to constitute a SpyCatcher-CAR (SpyCAR), while SpyTag is attached to the antibodies that recognize tumor antigens. With dimerization mediated by SpyCatcher and SpyTag, the number and activation level of SpyCARs recruited by tumor antigens depends on the SpyTag number in the "antibody-SpyTag" fusion protein. The results demonstrated that the increasing number of SpyTags effectively enhanced the cytotoxicity of SpyCAR-NK92 cells against target cells. The development of SpyCAR with tunable cytotoxicity provides a novel strategy for CAR-based tumor immunotherapies. • The SpyCAR system was developed based on non-covalent SpyCatcher-SpyTag. • The SpyCatcher-SpyTag interaction mediates enhanced cytotoxicity of SpyCAR-NK92 cells. • The cytotoxicity of SpyCAR-NK92 cells is in a SpyTag number-dependent manner. [ABSTRACT FROM AUTHOR]

Climate warming is modifying the movement of air masses over Northern latitudes, producing warming and cooling events across the boreal regions. These new conditions changes may mismatch plant phenology from weather conditions, and affect the growing period of trees. Understanding the processes of local adaptation in bud phenology can help to predict the response of plants to these rapid and unexpected environmental changes.Our study monitored bud burst and bud set weekly during four growing seasons in black spruce [Picea mariana (Mill.) B.S.P.] saplings planted in a common garden and originating from five provenances representing the whole latitudinal distribution of the closed boreal forest in Quebec, Canada. We compared the variance in bud phenology among populations and years, and analysed the relationships with temperatures at the origin sites.Bud burst and bud set occurred in mid‐May and mid‐July, respectively, with a large variability among provenances and between the study years. A delayed bud phenology was observed in the provenances from warmer sites, with bud burst and bud set being 1.1 and 1.4 days later for every additional degree in mean annual temperature at the origin site respectively. Populations with earlier bud bursts also showed earlier bud sets, thus the growing season was similar among provenances. The heritability of bud set was higher than that of bud burst, with estimates of 0.26 and 0.21 respectively. On average, variance in bud phenology among provenances reached 5.3%, which was higher than that within provenances (2.6%). The factor year explained 37.7%–69.7% of the variance in bud phenology.Synthesis. The findings demonstrate the evolutionary response to climate variations in the boreal biome. Endogenous and environmental components have different effects on the phases of bud burst and bud set. This complex interaction among drivers of bud phenology may prevent reliable predictions of changes in the growing season under changing climate. An earlier growth reactivation due to higher spring temperatures could result in higher frost risks to the developing buds. Despite a longer period for photosynthesis expected for the evergreen black spruce under warmer conditions, the period spent for bud development could remain unchanged. [ABSTRACT FROM AUTHOR]

Auxin is involved in various developmental processes of plants, including cell division in cambium and xylem differentiation. However, most studies linking auxin and xylem cell production are performed in environments with a strong seasonality (i.e. temperate and boreal climates). The temporal dynamics of auxin and cambial activity of subtropical trees remain basically unknown. In this study, we sampled four microcores weekly in three individuals of Chinese red pine (Pinus massoniana Lamb.) from February to December 2015–16 to compare xylem formation with auxin concentration in subtropical China. During the entire period of sampling, the number of cambial cells varied from 2 to 7, while the number of cells in the enlarging zone ranged from 1 to 4 and from 1 to 5 in the wall-thickening zone. In 2015, the average auxin concentration was 3.46 ng g−1, with 33 xylem cells being produced at the end of the year. In 2016, a lower auxin concentration (2.59 ng g−1) corresponded to a reduced annual xylem production (13.7 cells). No significant relationship between auxin concentration and number of xylem cells in differentiation was found at the weekly scale. Unlike in boreal and temperate forests, the lack of wood formation seasonality in subtropical forests makes it more difficult to reveal the relationship between auxin concentration and number of xylem cells in differentiation at the intra-annual scale. The frequent and repeated samplings might have reduced auxin concentration in the developing cambium and xylem, resulting in a lower xylem cell production. [ABSTRACT FROM AUTHOR]

Late frost can cause damage to trees, especially to the developing bud of broadleaf species in spring. Through long-term adaptation, plants adjust leaf phenology to achieve an optimal trade-off between growing season length and frost avoidance. In this study, we aim to assess ecotypic differentiation in leaf development of sugar maple populations planted in a common garden. A total of 272 sugar maple seedlings from 29 Canadian provenances were planted at the northern boundary of the natural range, and the phenological phases of bud and leaf development were monitored during spring 2019. The wide geographical area under evaluation showed a complex seasonal pattern of temperature, with spring warming occurring later in the north and close to the sea. Overall, leaf development lasted between 20 and 36 days, from the end of May to end of June. We observed different timings and rates of leaf development among provenances, demonstrating the occurrence of ecotypes in this species. Minimum April temperatures of the original sites were able to explain such differences, while maximum April temperatures were not significant. Seedlings from sites with colder minimum April temperatures completed leaf development earlier and faster. On average, leaf development diverged by up to 6 days among provenances, with minimum April temperatures ranging from −3 to 3 °C. Our results demonstrated that the avoidance of late spring frost is a driving force of leaf development in sugar maple populations. In the colder sites, the growing season is a limiting factor for tree growth. Thus, when thermal conditions become favorable in spring, an earlier growth reactivation and high metabolic activity ensure a fast leaf emission, which maximizes the period available for photosynthesis and growth. These patterns demonstrate the long-term phenological adaptation of sugar maple populations to local climatic conditions and suggest the importance of frost events for leaf development. [ABSTRACT FROM AUTHOR]

This paper investigated the effect of co-composting of lincomycin mycelia dregs (LMDs) with furfural slag on the degradation of lincomycin, maturity and microbial communities. Results showed that after 66 days composting, the concentration of lincomycin was removed above 99%. The final pH, C/N and germination index (GI) all met the national standards in maturity. Enumeration of total cultivable microbes showed the composting process was not inhibited by the addition of LMDs. Microbial diversity suggested that co-composting was beneficial to increase the abundance and diversity of bacterial communities for LMDs’ treatment. Canonical correlation analysis (CCA) indicated the bacteria communities were strongly affected by residual lincomycin, with lincomycin reduced greatly, microbial communities of T and CK became similar at the end of composting. The potential bacteria to degrade lincomycin were Anaerococcus , Peptostreptococcus , and Lactobacillus . Based on these results, this research indicated that the co-composting was a feasible treatment for LMDs. [ABSTRACT FROM AUTHOR]

China's subtropical forests play a vital role in sequestering global carbon; therefore, it is critical to conduct a precise investigation of intra-annual wood formation in these ecosystems to clarify the mechanisms behind this. Two field experiments were established in Chinese subtropical forests to monitor weekly the intra-annual xylem formation of Pinus massoniana Lamb. from January to December 2015, using the recently developed micro-sampling approach. The effects of climate on wood formation were also assessed using linear or mixed models. Results indicate that there is an inactive period that might be semi-dormancy in subtropical pine ecosystems in January compared with the complete dormancy in temperate and boreal ecosystems and the fully active or short-term dormancy in tropical ecosystems. The duration of xylem formation of Chinese red pine in subtropical China in 2015 was 4–6 months longer than temperate and boreal forests. Moreover, trees were found to grow better during the dry season than the wet season, indicating that the Chinese red pine ecosystem is more strongly regulated by net energy than by environmental factors. Our findings indicate that China's subtropical pine forests may benefit from the expected longer dry seasons, possibly leading to better forest growth and improved carbon sequestration under continued climate warming. [ABSTRACT FROM AUTHOR]

Abstract: Sludge-derived bio-charcoal (SDBC) was prepared from municipal sewage sludge by chemical activation with sulfuric acid followed by carbonization in this study. The important parameters for SDBC preparation process, which greatly affected the characteristics of SDBC were investigated. The optimized soak proportion, soak time and pyrolysis time were 1:1 (w/v), 8h and 30min, respectively. Adsorption experiments were conducted as function of pH, SDBC dosage, temperature, contact time and Cr (VI) initial concentration. The equilibrium adsorption data were fitted well to the Langmuir adsorption isotherm (r 2 >0.99). The calculated values of ΔS 0, ΔH 0, and ΔG 0 indicated that the adsorption was endothermic and not spontaneous. After 10h of adsorption at pH1.0 and 25°C with an adsorption dosage of 1.4gL−1, the maximum adsorption capacity of 61.3mgg−1 was reached at an initial Cr (VI) concentration of 240mgL−1. The maximum adsorption capacity (mgg−1) for Cr (VI) provided strong evidence of the potential of SDBC for removing Cr (VI) from aqueous solutions. [Copyright &y& Elsevier]

Five chemotypes, the isoborneol-type, camphora-type, cineole-type, linalool-type and borneol-type of Cinnamomum camphora (L.) Presl have been identified at the molecular level based on the multivariate analysis of mass spectral fingerprints recorded from a total of 750 raw leaf samples (i.e., 150 leaves equally collected for each chemotype) using desorption atmospheric pressure chemical ionization mass spectrometry (DAPCI-MS). Both volatile and semi-volatile metabolites of the fresh leaves of C. camphora were simultaneously detected by DAPCI-MS without any sample pretreatment, reducing the analysis time from half a day using conventional methods (e.g., GC-MS) down to 30 s. The pattern recognition results obtained using principal component analysis (PCA) was cross-checked by cluster analysis (CA), showing that the difference visualized by the DAPCI-MS spectral fingerprints was validated with 100% accuracy. The study demonstrates that DAPCI-MS meets the challenging requirements for accurate differentiation of all the five chemotypes of C. camphora leaves, motivating more advanced application of DAPCI-MS in plant science and forestry studies. [ABSTRACT FROM AUTHOR]

Adoptive chimeric antigen receptor (CAR)-modified T or NK cells (CAR-T/NK) have emerged as a novel form of disease treatment. Lentiviral vectors (LVs) are commonly employed to engineer NK cells for the efficient expression of CARs. This study reported the influence of single-promoter and dual-promoter LVs on the CAR expression and cytotoxicity of engineered NK cells. We constructed a third-generation NKG2D-based CAR that kills cancer cells by targeting up to eight stress-induced ligands (NKG2DLs). Our results demonstrated that the CAR exhibits both a higher expression level and a higher coexpression concordance with the GFP reporter in HEK-293T or NK92 cells by utilizing the optimized single-promoter pCDHsp rather than the original dual-promoter pCDHdp. After puromycin selection, the pCDHsp produces robust CAR expression and enhanced in vitro cytotoxicity of engineered NK cells. Therefore, infection with a single-promoter pCDHsp lentivector is recommended to prepare CAR-engineered NK cells. This research helps to optimize the production of CAR-NK cells and enhance their functional activity, to provide CAR-NK cell products with better and more uniform quality. [ABSTRACT FROM AUTHOR]

Atmospheric nitrogen (N) deposition and increasing precipitation affect carbon sequestration in terrestrial ecosystems, but how these two concurrent global change variables affect xylem growth in trees (i.e. independently or interactively) remains unclear. We conducted novel experiments in central China to monitor the xylem growth in a dominant species (Quercus acutissima Caruth.) in response to N addition (CN), supplemental precipitation (CW) or both treatments (CNW), compared with untreated controls (C). Measurements were made at weekly intervals during 2014–15. We found that supplemental precipitation significantly enhanced xylem growth in the dry spring of 2015, indicating a time-varying effect of increased precipitation on intra-annual xylem growth. Elevated N had no significant effect on xylem increment, xylem growth rate, and lumen diameters and potential hydraulic conductivity (K s) of earlywood vessels, but K s with elevated N was significantly negatively related to xylem increment. The combination of additional N and supplemental precipitation suppressed the positive effect of supplemental precipitation on xylem increment in the dry spring of 2015. These findings indicated that xylem width was more responsive to supplemental precipitation than to increasing N in a dry early growing season; the positive effect of supplemental precipitation on xylem growth could be offset by elevated N resources. The negative interactive effect of N addition and supplemental precipitation also suggested that increasing N deposition and precipitation in the future might potentially affect carbon sequestration of Q. acutissima during the early growing season in central China. The effects of N addition and supplemental precipitation on tree growth are complex and might vary depending on the growth period and local climatic conditions. Therefore, future models of tree growth need to consider multiple-time scales and local climatic conditions when simulating and projecting global change. [ABSTRACT FROM AUTHOR]

It is critical to investigate the effects of competition and climate on forest growth as they are main forces affecting forest dynamics. However, in subtropics of China such a study has never been conducted. Here we conducted a pioneer study to evaluate the effects of competition and climate on growth of Chinese red pine (Pinus massoniana) in mixed forests of subtropical China along a broad latitudinal gradient (23°N∼32°N). Twenty-three plots (20m × 20m) were randomly selected from 11 sites and competition and tree radial growth data were collected. Principal component analysis (PCA) was used to detect the potential spatial pattern in site-specific standard tree-ring chronologies during the common period (1990-2015). The linear mixed-effect models (LMMs) were employed to quantify the relationships between cumulated basal area increment (5, 10, 15, 20 and 25 years) of subject trees and six distance-independent competition indices. The relationships between tree radial growth and climate were evaluated by response analyses. Finally the best predicted competition index and climate factor were employed in a full model and their relative importance were calculated. The PCA results allowed classifying the mixed forests into southeastern and northern groups along the Nanling Mountains and Wuyi Mountains. LMMs results revealed that competition pressures mainly come from density and size of larger individuals. Response coefficients demonstrated that precipitation in September and sunshine duration in October influenced trees radial growth of southeastern group and northern group respectively. Our results clearly showed that effects of competition on tree radial growth decreased from southeast to north while effects of climates increasing over this large spatial scale. This is the first attempt to clarify the effects of competition, and further quantify the contributions of competition and climate on tree radial growth in China subtropics. Our finds will certainly contribute to a better policy-making for sustainable forest management. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • More than 99% of the residual lincomycin was removed after composting. • Potential degradation products of lincomycin were identified via composting. • Total RAs of ARGs and intI1 were higher in LMDs compost. • Bacterial communities were the main factor to affect the variation of ARGs. • There existed environmental risk in LMDs compost. Abstract This study explored the effects of co-composting of lincomycin mycelia dregs (LMDs) with furfural slag on variations in antibiotic resistance genes (ARGs) and the bacterial community. The results showed that more than 99% lincomycin was reduced after composting. Moreover, the total absolute and relative abundance of ARGs increased by 180 and 5 times, respectively. The gene lnuA was detected in the LMDs compost and it was proved to participate in lincomycin biodegradation based on the analysis of Pearson's correlation and the lincomycin degradation byproducts. Redundancy analysis showed the succession of the bacterial community had a greater influence than the environmental parameters (residual lincomycin, C/N, pH and temperature) on the variation of ARGs during composting. Composting was not effective in reducing most of the ARGs and intI1 and thus the LMDs compost is dangerous to the ecological environment. [ABSTRACT FROM AUTHOR]

Tree xylem anatomy is associated with carbon accumulation and wood quality. Increasing nitrogen (N) deposition can cause a significant effect on xylem anatomy, but related information is limited for subtropical broadleaf tree species. A 3-year field N addition experiment, with different N addition approaches (canopy and understory) and addition rates (0, 25, and 50 kg N ha −1  yr −1 ), was performed beginning in 2013 in a subtropical forest of China. N addition effects on xylem tracheid (wall and lumen) size, vessel, and growth of dominant broadleaf species ( Schima superba Gardn . et Champ . and Castanopsis chinensis ( Sprengel ) Hance ) were investigated. The results showed that The effect of N addition on tracheid size was dependent on the tree species and addition approaches. Canopy N addition did not affect the tracheid size of C . chinensis , while both addition approaches increased the tracheid size of S . superba . The vessel size of both species was not affected by N addition. There was no difference in radial growth or other growth-related variables between the control and N-treated trees. These findings indicated that short-term N addition could significantly affect xylem anatomy, but might not influence tree growth. Meanwhile, understory N addition may pose challenges for mechanistic understanding and forest dynamics projection. [ABSTRACT FROM AUTHOR]

Huanglongbing (HLB), a devastating disease for citrus worldwide, is caused by Candidatus Liberibacter asiaticus (C Las). In this study, we employed a novel extractive electrospray ionization-mass spectrometry (EESI-MS) method to analyze the metabolites in leaves of uninfected and HLB-infected Newhall navel orange. The results showed that uninfected and HLB-infected leaves could be readily distinguished based on EESI-MS combined by multivariable analysis. Nine phenolic compounds involved in phenylpropanoid pathway, such as p -coumaric acid, naringin, and apigenin, were principal components to distinguish the leaves of uninfected and HLB-infected Newhall navel orange. Gene expression was also conducted to further explore the molecular mechanism of phenylpropanoid branch pathway in HLB. The expression of genes (4CL , HCT , CHI , CHS , CYP , and C12R) involved in phenylpropanoid branch pathway was increased in asymptomatic and early period of HLB-infected leaves, while decreased in later period of HLB-infected leaves. This study provides a novel method for early detection of citrus HLB and suggests the regulation mechanism of phenylpropanoid pathway in the interaction between citrus and C Las. [Display omitted] • Extractive electrospray ionization-mass spectrometry method was established. • EESI-MS could be a powerful approach for early detection of Huanglongbing. • Phenylpropanoid pathway may play an important role in resisting Huanglongbing. [ABSTRACT FROM AUTHOR]

A miniature thermal dissociation atmospheric chemical ionization (TDCI) source, coupled with LTQ-MS, has been developed for rapid trace detection of pesticide residues such as dimethoate in highly viscous fruit juice samples. Instead of toxic organic solvents and the high electric field used in the conventional ionizations, an ionic liquid, a “green solvent”, was employed to directly generate reagent ions in the TDCI process, followed by the proton or charge transfer with the analytes prior to the LTQ instrument for mass analysis. Trace amounts of dimethoate in fresh orange juices have been quantitatively detected, without any sample pretreatment or aid of high-pressure gas. A low limit of detection (LOD = 8.76 × 10−11 g mL−1), acceptable relative standard deviation (RSD = 3.1–10.0%), and reasonable recoveries (91.2–102.8%) were achieved with this method for direct detection of dimethoate in highly viscous orange juice samples. The average analysis time for each single sample was less than 30 seconds. These experimental results showed that the miniature TDCI developed here is a powerful tool for the fast trace detection of pesticide residues in complex viscous fruit juices, with the advantage of high sensitivity, high speed, and high-throughput, ease of operation, and so on. Because of no chemical contamination and high voltage damage to the analytes and the environment, the technique has promising applications for online quality monitoring in the area of food safety. [ABSTRACT FROM AUTHOR]