Development and validation of a nomogram for predicting lymph node metastasis in ductal carcinoma in situ with microinvasion: A SEER population-based study.

BACKGROUND: Ductal carcinoma in situ with microinvasion (DCIS-MI) is a special type of breast cancer. It is an invasive lesion less than 1.0 mm in size related to simple ductal carcinoma in situ (DCIS). Lymph node metastasis (LNM) in DCIS-MI often indicates a poor prognosis. Therefore, the management of lymph nodes plays a vital role in the treatment strategy of DCIS-MI. Since DCIS-MI is often diagnosed by postoperative paraffin section and immunohistochemical detection, to obtain the best clinical benefits for such patients, we aim to establish and verify a nomogram to predict the possibility of lymph node metastasis in DCIS-MI patients and help preoperative or intraoperative clinical decision-making. METHODS: A retrospective analysis of patients with DCIS-MI in the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2019 was performed. The study cohort was randomly divided into a training cohort and a validation cohort at a ratio of 7:3. The risk factors were determined by univariate and multivariate logistic regression analyses in the training cohort, and a nomogram was constructed. The receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to evaluate the nomogram in the training set and validation set. An independent data cohort was obtained from the Shanghai Jiao Tong University Breast Cancer Database (SJTU-BCDB) for external validation. RESULTS: This study included 3951 female patients from SEER with DCIS-MI, including 244 patients with regional lymph node metastasis, accounting for 6.18% of the total. An independent test set of 323 patients from SJTU-BCDB was used for external validation. According to the multifactorial logistic regression analysis results, age at diagnosis, ethnicity, grade, and surgical modality were included in the prediction model. The areas under the ROC curves (AUCs) were 0.739 (95% CI: 0.702~0.775), 0.732 (95% CI: 0.675~0.788), and 0.707 (95%CI: 0.607-0.807) in the training, validation and external test groups, suggesting that the column line graphs had excellent differentiation. The calibration curves slope was close to 1, and the model's predicted values were in good agreement with the actual values. The DCA curves showed good clinical utility. CONCLUSION: In this study, we constructed accurate and practical columnar maps with some clinical benefit to predict the likelihood of lymph node metastasis in patients with postoperatively diagnosed DCIS-MI and provide a reference value for specifying treatment strategies.

Clinicopathological differences and survival benefit in ER+/PR+/HER2+ vs ER+/PR-/HER2+ breast cancer subtypes.

INTRODUCTION: Breast cancer subtypes based on estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expression have significant implications for prognosis. HER2-positive tumors historically demonstrated poorer survival, but anti-HER2 targeted therapy improved outcomes. However, hormone receptor (HR)-positive patients may experience reduced benefit due to HER2-HR signaling crosstalk. METHODS: Data from two databases, the Shanghai Jiao Tong University Breast Cancer Data Base (SJTUBCDB) and the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database, were analyzed. Propensity score adjustments were used to balance patient characteristics between ER+/PR+/HER2+ and ER+/PR-/HER2+ subtypes. Kaplan-Meier survival curves estimated disease-free survival (DFS), breast cancer-specific survival (BCSS), overall survival (OS) for these subtypes in the SJTUBCDB, while subgroup analyses using multivariable models were performed based on menstruation, pN stage, HER2-targeted therapy, and endocrinotherapy. RESULTS: The ER+/PR+/HER2+ group showed significantly better DFS and BCSS than the ER+/PR-/HER2+ group, particularly in postmenopausal and pN0 stage patients. Survival outcomes were similar after anti-HER2 therapy or endocrine aromatase inhibitor (AI) therapy in both groups. However, among patients receiving selective estrogen receptor modulator (SERM) treatment, those in the ER+/PR-/HER2+ group had a significantly worse prognosis compared to ER+/PR+/HER2+ patients. CONCLUSIONS: HER2-positive breast cancers with different HR statuses exhibit distinct clinicopathological features and survival outcomes. Patients in the ER+/PR+/HER2+ group generally experience better survival, particularly in postmenopausal and pN0 stage patients. Treatment strategies should consider HR status and specific modalities for better personalized management.

Phytoremediation and environmental effects of three Amaranthaceae plants in contaminated soil under intercropping systems.

Intercropping is a widely used agricultural system; however, the effect of intercropping between accumulator plants on phytoextraction in heavy metal-contaminated soils remains unknown. Here, a field experiment was conducted to investigate the phytoextraction efficiency and related environmental effects of three Amaranthaceae plants (Amaranthus hypochondriacus, Celosia argentea, and Pfaffia glomerata) using mono- and intercropping models. In monocropping, the total biomass of A. hypochondriacus was only 51.2 % of that of C. argentea. Compared with monocropping, intercropping reduced the fresh weight per plant of A. hypochondriacus by 53.0 % (intercropping with C. argentea) and 40.5 % (intercropping with P. glomerata) but increased the biomass per plant of C. argentea and P. glomerata by 128.2 and 14.2 %, respectively. The Cd uptake of the three plants in the monocropping models showed the following trend: C. argentea > P. glomerata > A. hypochondriacus. Interplanting A. hypochondriacus and C. argentea further increased the phytoextraction efficiency by 361.2 % (compared with A. hypochondriacus monocropping) and 52.0 % (compared with C. argentea monocropping). Soil exchangeable Cd, Pb, Cu, Zn, K, and P, soil N-NO3- and N-NH4+, soil common bacteria and arbuscular mycorrhiza (AM) fungi, and soil total organic carbon (TOC) play key roles in Cd and Pb uptake by the three accumulator plants (p < 0.05). The biomass of common bacteria, Gm+, Gm- bacteria, fungi, AM fungi, and actinomycetes increased with the three accumulators planted in the mono- and intercropping models. Compared with C. argentea monocropping, the biomass of soil microbes in the rhizosphere soil was obviously increased in the intercropping A. hypochondriacus and C. argentea models. These results suggest that interplanting A. hypochondriacus and C. argentea can increase Cd removal efficiency from Cd-contaminated soils, and this model could be recommended to remediate Cd-contaminated soils on a field scale.

Survival outcomes of low-risk papillary thyroid carcinoma at different risk levels: a corollary for active surveillance.

Background: This study aims to compare the outcomes of active surveillance (AS) in low-risk papillary thyroid carcinoma (PTC) patients with different tumor sizes and lymph node metastasis status, in order to establish appropriate management strategies. By analyzing these results, this study provides valuable insights for the effective management of such patients, addressing the issues and challenges associated with AS in practical clinical practice. Methods: The study utilized the SEER database supported by the National Cancer Institute of the United States, extracting data of PTC diagnosed between 2000 and 2015. Statistical analyses were conducted using inverse probability weighting (IPTW) and propensity score matching (PSM), including Kaplan-Meier survival curves and Cox regression models, to evaluate the impact of different tumor sizes and lymph node metastasis status on thyroid cancer-specific survival (TCSS). Results: A total of 57,000 PTC patients were included, with most covariates having standardized mean differences below 10% after IPTW and PSM adjustments. The TCSS of PTC with a diameter smaller than 13mm is significantly better than that of tumors with a diameter larger than 13mm, regardless of the presence of lymph node metastasis. Among PTC cases with a diameter smaller than 13mm, the TCSS of patients is similar, regardless of the presence of lymph node metastasis. However, in PTC cases with a diameter larger than 13mm, the presence of lateral neck lymph node metastasis (N1b stage) significantly impacts the TCSS, although the absolute impact on TCSS rate is minimal. Conclusion: The treatment strategy of AS is safe for patients with T1a stage papillary thyroid microcarcinoma (PTMC). However, for patients with T1b stage, if the tumor diameter exceeds 13mm or there is lymph node metastasis in the lateral neck region, the TCSS will be significantly affected. Nevertheless, the absolute impact on survival is relatively small.

Survival Benefit of Adjuvant Chemotherapy in Node-Positive Breast Cancer With a 21-Gene Recurrence Score of 14 to 25: A Real-World Study Based on the Inverse Probability of Treatment Weighting Method.

INTRODUCTION: The role of recurrence score in predicting the benefits of adjuvant chemotherapy for lymph-node-positive breast cancer remains uncertain. We studied chemotherapy usage in patients with 1 to 3 positive lymph nodes and a recurrence score (RS) of 25 or lower to assess changes in clinical practice based on the RxPONDER trial. METHODS: A retrospective study using the SEER database identified female patients diagnosed with ER-positive, HER2-negative breast cancer, 1 to 3 positive lymph nodes, and an RS of 25 or lower between 2010 and 2015. Patients were divided into nonchemotherapy and chemotherapy groups, with propensity score weighting to balance clinicopathologic factors. RESULTS: Among 7965 patients, 5774 (72.5%) were in the nonchemotherapy group, while 2191 (27.5%) were in the chemotherapy group. Median follow-up was 39 months. Breast cancer accounted for 67 deaths, while 128 deaths were due to other causes. The weighted 5-year overall survival (OS) rates were 95.7% for the nonchemotherapy group and 97.2% for the chemotherapy group. For high-risk patients, the weighted 5-year OS rates were 95.2% and 97.0% for the nonchemotherapy and chemotherapy groups, respectively, with a significant absolute difference of 1.8% (P = .014). Multivariate analysis showed a significant difference in weighted hazard ratios for OS between the nonchemotherapy and chemotherapy groups in high-risk patients (hazard ratio: 0.64; 95% CI: 0.48-0.86). However, there were no significant differences in weighted hazard ratios for lower-risk patients, and similar results were observed for breast cancer-specific survival (BCSS). CONCLUSION: Patients with ER-positive, HER2-negative breast cancer and 1 to 3 positive lymph nodes, assessed by a 21-gene RS of 0 to 25, exhibited heterogeneous prognosis. Adjuvant chemotherapy provided a significant survival benefit, especially for patients with RS of 14 to 25, particularly those with invasive ductal carcinoma (IDC) and 2 to 3 positive lymph nodes.

Boosting photocatalytic nitrogen reduction reaction by Jahn-Teller effect.

Compared with traditional the Haber-Bosch process, photocatalytic ammonia production has attracted a considerable attention due to its advantages of low energy consumption and sustainability. In this work, we mainly study the photocatalytic nitrogen reduction reaction (NRR) on MoO3·0.55H2O and α-MoO3. Structure analysis shows that compared to α-MoO6, the [MoO6] octahedrons in MoO3·0.55H2O obviously distort (Jahn-Teller distortion), leading to the formation of Lewis acid active sites that favors the adsorption and activation of N2. X-ray photoelectron spectroscopy (XPS) further confirms the formation of more Mo5+ as Lewis acid active sites in MoO3·0.55H2O. Transient photocurrent, photoluminescence and electrochemical impedance spectra (EIS) confirmed that MoO3·0.55H2O has a higher charge separation and transfer efficiency than α-MoO3. Density functional theory (DFT) calculation further confirmed that the N2 adsorption on MoO3·0.55H2O is more favorable thermodynamically than that on α-MoO3. As a result, under visible light irradiation (λ ≥ 400 nm) for 60 min, an ammonia production rate of 88.6 µmol·gcat-1 was achieved on MoO3·0.55H2O, which is about 4.6 times higher than that on α-MoO3. In comparison to other photocatalysts, MoO3·0.55H2O exhibits an excellent photocatalytic NRR activity under visible light irradiation without using sacrificial agent. This work offers a new fundamental understanding to photocatalytic NRR from the viewpoint of crystal fine structure, which benefits designing efficient photocatalysts.

Magnetic resonance imaging in screening women at high risk of breast cancer: A meta-analysis.

BACKGROUND: Magnetic resonance imaging (MRI) is more accurate than mammography in screening for breast cancer. Exposure to ionizing radiation from repeated diagnostic X-rays may be a cause of breast cancer. METHODS: We conducted systematic searches on PubMed, Cochrane and Embase to identify studies on women who underwent mammography or MRI screening. A meta-analysis was performed to compare the detection rate of breast cancer by mammography, MRI or both. RESULTS: A total of 18 diagnostic publications were identified and included in the meta-analysis. Among the 1000 screened women, MRI alone increased the detection rate of breast cancer by 8 compared with mammography alone (RR 0.48, 95% CI 0.42-0.54), and MRI plus mammography increased the detection rate of breast cancer by 1 compared with MRI alone (RR 0.86, 95% CI 0.78-0.96). Subgroup analysis demonstrated that the diagnostic efficacy of MRI plus mammography in breast was obviously better than that of MRI alone or mammography alone. CONCLUSIONS: Screening with MRI alone might be the best choice for women at high risk of breast cancer.

Negatively charged nano-hydroxyapatite can be used as a phosphorus fertilizer to increase the efficacy of wollastonite for soil cadmium immobilization.

Improper application of phosphorus (P) fertilizer during soil cadmium (Cd) immobilization reduces the efficiency of fertilizer and Cd remediation. In this study, we synthesized three types of nano-hydroxyapatite (NHAP) with different surface charges as slow-release P fertilizers during Cd immobilization. We also evaluated the effects of wollastonite application with or without NHAP addition, in comparison with triple superphosphate (TSP) or bulk hydroxyapatite, on Cd accumulation in Amaranthus tricolor L. The results showed that adding wollastonite significantly reduced P availability (23.5%) in the soil, but it did not inhibit plant P uptake. In wollastonite-amended soil, the application of negatively/positively charged NHAP significantly increased plant biomass by 643-865% and decreased Cd uptake by 74.8-75.1% compared to the unamended soil as well as showed greater efficiency than those with TSP. This was ascribed to the increased soil pH (from 3.94 to 6.52-6.63) and increased abundance of organic acids (including citric acid, malic acid, lactic acid, and acetic acid) secreted by plants. In addition, the P-preferring bacterial class Bacteroidia was specific to soils amended with both wollastonite and NHAP-. These results suggest that NHAP- may be an appropriate P fertilizer for soil Cd immobilization using wollastonite.

Pfaffia glomerata is a hyperaccumulator candidate: Cd and Zn tolerance, absorption, transfer, and distribution.

Pfaffia glomerata is a candidate for phytoremediation due to its high biomass and high bioaccumulation efficiency of multiple heavy metals. It is essential to further evaluate its tolerance, absorption, transfer, and distribution to multiple heavy metals. In the current study, we evaluated the tolerance, absorption, transfer, and distribution of P. glomerata in a Cd/Pb/Cu/Zn combined-contaminated environment by two hydroponic experiments. The results demonstrated that P. glomerata was not affected by Cd/Pb/Cu/Zn exposure, except for the 50 µM Cd/Pb/Cu/Zn treatment, which significantly decreased the stem biomass. In a single Cd, Pb, Cu, and Zn exposure, the root of P. glomerata absorbed Cd/Pb/Cu/Zn in the order of Cd > Zn > Pb > Cu. Almost all Pb and Cu accumulated in the plant roots and were hardly transferred to the aboveground parts. Therefore, the order of total Cd/Pb/Cu/Zn extraction of a single plant in multiple Cd/Pb/Cu/Zn exposures at the same concentration was Cd > Zn > Pb > Cu. The bioconcentration factor (BCF) of Cd and Zn in roots, stems, and leaves increased with the concentration of Cd and Zn in the solution, and was > 1. In contrast with Cd and Zn, the BCFs of Cu and Pb in the stems and leaves were < 1. The element distribution of Pb, Cu, Zn, and Mn in the stem of P. glomerata was dispersed, indicating that the stem of P. glomerata does not have a detoxification mechanism for distributing metals to the area of low biological activity. The total amount of tartaric acid, critic acid, and DOC secreted by P. glomerata roots decreased with the increase in Cd/Pb/Cu/Zn exposure. However, further investigation is needed to unravel the interaction between the LMWOAs secreted by the root of P. glomerata and heavy metals.

Effect of Polishing on Lead and Cadmium Bioavailability in Rice and Its Health Implications.

Rice polishing is an important approach to reducing the concentrations of heavy metals in rice, but knowledge of its effect on the Pb and Cd bioavailability in produced rice and the related health risk remains limited. In this study, the effects of rice polishing on the bioaccessibility (BAC) and bioavailability (RBA) of Pb and Cd in rice are assessed using an in vitro method and an in vivo mouse bioassay. The Pb removal rate in brown rice (40%), lightly processed brown rice (62%), germinated rice (74%), and polished rice (79%) gradually enhanced with an increase in the polishing degree, while Cd was difficult to remove by polishing. The Pb and Cd BAC in germinated rice was the highest, while that in brown rice was the lowest. The polished rice Pb and Cd RBA in the liver and kidneys were significantly higher than those in the brown rice group. The Pb RBA in the livers and kidneys in the polished rice group was 26.6% ± 1.68% and 65.3% ± 0.83%, respectively, which was 1.6- and 2.6-times higher than that in the brown rice group, respectively. The Cd RBA values in both the livers and kidneys of the polished rice group were 1.3-times higher than those in the brown rice group. Although polishing reduced the total Pb in the polished rice, it was not enough to offset the increase in bioavailability, and its consumption risk was not weakened. This study highlighted the value of the oral-bioavailability-corrected health risk assessment for assessing the influence of rice polishing on Pb and Cd exposure via rice consumption.

Two novel predictive biomarkers for osteosarcoma and glycolysis pathways: A profiling study on HS2ST1 and SDC3.

INTRODUCTION: Prognostic biomarkers for osteosarcoma (OS) are still very few, and this study aims to examine 2 novel prognostic biomarkers for OS through combined bioinformatics and experimental approach. MATERIALS AND METHODS: Expression profile data of OS and paraneoplastic tissues were downloaded from several online databases, and prognostic genes were screened by differential expression analysis, Univariate Cox analysis, least absolute shrinkage and selection operator regression analysis, and multivariate Cox regression analysis to construct prognostic models. The accuracy of the model was validated using principal component analysis, constructing calibration plots, and column line plots. We also analyzed the relationship between genes and drug sensitivity. Gene expression profiles were analyzed by immunocytotyping. Also, protein expressions of the constructed biomarkers in OS and paraneoplastic tissues were verified by immunohistochemistry. RESULTS: Heparan sulfate 2-O-sulfotransferase 1 (HS2ST1) and Syndecan 3 (SDC3, met all our requirements after screening. The constructed prognostic model indicated that patients in the high-risk group had a much lower patient survival rate than in the low-risk group. Moreover, these genes were closely related to immune cells (P < .05). Drug sensitivity analysis showed that the 2 genes modeled were strongly correlated with multiple drugs. Immunohistochemical analysis showed significantly higher protein expression of both genes in OS than in paraneoplastic tissues. CONCLUSIONS: HS2ST1 and SDC3 are significantly dysregulated in OS, and the prognostic models constructed based on these 2 genes have much lower survival rates in the high-risk group than in the low-risk group. HS2ST1 and SDC3 can be used as glycolytic and immune-related prognostic biomarkers in OS.

Study on the Motion Characteristics of Solid Particles in Fine Flow Channels by Ultrasonic Cavitation.

Microjets caused by the cavitation effect in microchannels can affect the motion trajectory of solid particles in microchannels under ultrasonic conditions. The optimal parameters for an observation experiment were obtained through simulations, and an experiment was designed to verify these parameters. When the cavitation bubbles collapse in the near-wall area, the solid particles in the microchannel can be displaced along the expected motion trajectory. Using fluent software to simulate the bubble collapse process, it can be seen that, when an ultrasonic sound pressure acts on a bubble near the wall, the pressure causes the top of the bubble wall to sink inward and eventually penetrate the bottom of the bubble wall, forming a high-speed microjet. The maximum speed of the jet can reach nearly 28 m/s, and the liquid near the top of the bubble also moves at a high speed, driving the particles in the liquid towards the wall. A high-speed camera was used to observe the ultrasonic cavitation process of bubbles in the water to verify the simulation results. A comparison of particle motion with and without ultrasonic waves proved the feasibility of using the ultrasonic cavitation effect to guide small particles towards the wall. This method provides a novel experimental basis for changing the fluid layer state in the microchannel and improving precision machining.

Nitrogen and phosphorus addition exerted different influences on litter and soil carbon release in a tropical forest.

Terrestrial soils release large amount of carbon dioxide (CO2) each year, which are mainly derived from litter and soil carbon (C) decomposition. Nutrient availability, especially nitrogen (N) and phosphorus (P), plays an important role in both litter and soil C decomposition. Therefore, understanding the underlying mechanism is crucial for mitigating CO2 emission and climate changes. Here, we assessed patterns of litter and soil C decomposition after 11 yrs. in-situ N and P addition in a tropical forest where corn leaves or corn roots were added as litter C. The total CO2 efflux was quantified and partitioned using 13C isotope signatures to determine the sources (litter or soil C) every three months. In addition, Changes in C-degrading enzyme activities: ß-1,4-glucosidase (BG), phenol oxidase (PHO) and peroxidase (PER), and microbial biomarkers were assessed to interpret the underlying mechanism. Total C-release was enhanced up to17% by the long-term N addition but inhibited up to 15% by P addition. Precisely, N addition only accelerated the litter decomposition and increased about 42% and 6% of the litter C release at 0-5 cm and 5-10 cm soil depths, respectively; while P addition only impeded the soil C decomposition and decreased about 9% and 11% of the soil C release at 0-5 cm and 5-10 cm, respectively. The enhanced C release under N addition might be attributed to the enhanced microbial biomass, the ratio of fungi to bacteria and C-degrading enzyme activities. However, P addition resulted in the reverse result in microbial properties and C-degrading enzyme activities, associated with a decreased C release. Our study suggests that the long-term N and P addition selectively affected the litter and soil C decomposition because of their different physiochemical properties and this tendency might be more pronounced in tropical forests exposed to increasing atmospheric N deposition in the future. The study indicates that the different patterns of litter and soil C decomposition under climate change should be taken account in the future C management strategies.

Phosphate fertilizers facilitated the Cd contaminated soil remediation by sepiolite: Cd mobilization, plant toxicity, and soil microbial community.

In-situ immobilization does not remove Cd from the contaminated soil. It is vital to investigate the effects of fertilizers on soil Cd mobility during remediation with amendments. In the current study, a pot experiment was conducted to investigate the effects of calcium magnesium phosphate (CMP) and calcium superphosphate (SSP) on the remediation of Cd-contaminated soil by sepiolite. We mainly focused on changes in soil Cd immobilization, plant toxicity, and soil microbial communities after applying two phosphates during Cd-contaminated soil remediation by sepiolite. The results demonstrated that sepiolite decreased Cd concentration in brown rice, straw, and roots by 32.66%, 38.89%, and 30.94%, respectively. During soil remediation by sepiolite, the Cd concentrations of brown rice and straw were not affected by CMP or SSP, except for the treatment with sepiolite plus high-dose CMP. Sepiolite significantly decreased HCl-extractable Cd and DTPA-extractable Cd by 32.21% and 10.50%, respectively. During soil remediation by sepiolite, the HCl-extractable and DTPA-extractable Cd further decreased with CMP or SSP. The decreasing amplitude with CMP was 40.57-72.60% and 7.05-14.53%, and that of SSP was 37.68-59.66% and 20.71-25.07%, respectively. The superoxide dismutase, peroxidase, catalase activities, and malondialdehyde concentration in rice roots decreased inordinately with the addition of sepiolite, CMP, and SSP, indicating that the application of sepiolite, CMP, or SSP alleviated Cd-induced rice root stress and protected rice roots from Cd toxicity. Alpha diversity estimators (including the Chao, ACE, and Shannon indices) indicated that sepiolite, CMP, or SSP applications had no adverse effects on soil bacterial richness and diversity. Hierarchical clustering analysis revealed that the two phosphate fertilizers and sepiolite were the main factors affecting changes in the bacterial communities structure. Redundancy analysis revealed that soil pH, Eh, and soil-extractable Cd were critical factors affecting the structure of the bacterial communities.

Toxicokinetics of metals in the soil invertebrate Enchytraeus crypticus exposed to field-contaminated soils from a mining area.

Toxicokinetics may help assessing the risk of metal-contaminated soils by quantifying the development of internal metal concentrations in organisms over time. This study assessed the toxicokinetics in Enchytraeus crypticus of non-essential (Pb and Cd) and essential elements (Zn and Cu) in metal-contaminated field soils from a mining area, containing 3.49-24.3 mg Cd/kg dry soil, 433-1416 mg Pb/kg dry soil, 15.7-44.9 mg Cu/kg dry soil and 1718-6050 mg Zn/kg dry soil. Three different uptake-elimination patterns in E. crypticus were found. Both essential elements (Zn and Cu) showed fast increasing internal concentrations reaching equilibrium within 2 d in the uptake phase, without hardly any elimination after transfer to clean soil. The non-essential Cd showed a slow linear accumulation and excretion with body concentrations not reaching steady state within 21 d. Internal Pb concentrations, however, reached equilibrium within 7 d in the uptake phase. Longer exposure times in ecotoxicological tests, therefore, are required for elements like Cd. Porewater pH and dissolved organic carbon (DOC) levels were the dominant factors controlling Cd uptake from the test soils. The 21-d body Cd and Pb concentrations were best explained from 0.01 M CaCl2-extractable soil concentrations. Steady-state Cu and Zn body concentrations were independent of soil exposure concentrations. Bioaccumulation factors (BAF) were low for Pb (<0.1 kgsoil/kgworm), but high for Cd at 1.78-24.3 kgsoil/kgworm, suggesting a potential risk of Cd biomagnification in the terrestrial food chain of the mining area ecosystem.

The genome of the Paleogene relic tree Bretschneidera sinensis: insights into trade-offs in gene family evolution, demographic history, and adaptive SNPs.

Among relic species, genomic information may provide the key to inferring their long-term survival. Therefore, in this study, we investigated the genome of the Paleogene relic tree species, Bretschneidera sinensis, which is a rare endemic species within southeastern Asia. Specifically, we assembled a high-quality genome for B. sinensis using PacBio high-fidelity and high-throughput chromosome conformation capture reads and annotated it with long and short RNA sequencing reads. Using the genome, we then detected a trade-off between active and passive disease defences among the gene families. Gene families involved in salicylic acid and MAPK signalling pathways expanded as active defence mechanisms against disease, but families involved in terpene synthase activity as passive defences contracted. When inferring the long evolutionary history of B. sinensis, we detected population declines corresponding to historical climate change around the Eocene-Oligocene transition and to climatic fluctuations in the Quaternary. Additionally, based on this genome, we identified 388 single nucleotide polymorphisms (SNPs) that were likely under selection, and showed diverse functions in growth and stress responses. Among them, we further found 41 climate-associated SNPs. The genome of B. sinensis and the SNP dataset will be important resources for understanding extinction/diversification processes using comparative genomics in different lineages.

Delayed wet season increases soil net N mineralization in a seasonally dry tropical forest.

Seasonal precipitation regime plays a vital role in regulating nutrient dynamics in seasonally dry tropical forests. Present evidence suggests that not only wet season precipitation is increasing in the tropics of South China, but also that the wet season is occurring later. However, it is unclear how nutrient dynamics will respond to the projected precipitation regime changes. We assessed the impacts of altered seasonal precipitation on soil net N mineralization in a secondary tropical forest. Since 2013, by reducing throughfall and/or irrigating experimental plots, we delayed the wet season by two months from April-September to June-November (DW treatment) or increased annual precipitation by 25% in July and August (WW treatment). We measured soil net N mineralization rates and assessed soil microbial communities in January, April, August and November in 2015 and 2017. We found that a wetter wet season did not significantly affect soil microbes or net N mineralization rates, even in the mid-wet season (August) when soil water content in the WW treatment increased significantly. By contrast, a delayed wet season enhanced soil microbial biomass and altered microbial community structure, resulting in a two-fold increase in net N mineralization rates relative to controls in the early dry season (November). Structural equation modeling showed that the changes in net N mineralization during the early dry season were associated with altered soil microbial communities, dissolved organic N, and litterfall, which were all affected by enhanced soil water content. Our findings suggest that a delayed wet season could have a greater impact on N dynamics than increased precipitation during the wet season. Changes in the seasonal timing of rainfall might therefore influence the functioning of seasonally dry tropical forests.

Joint approaches to reduce cadmium exposure risk from rice consumption.

In-situ soil cadmium (Cd) immobilization helps to reduce Cd accumulation in rice grain, while its effects on bioaccessibility of Cd in rice during digestion and the associated health risk from rice consumption remain unclear. Here, we combined in-situ soil Cd immobilization and bioaccessibility-corrected health risk assessment (HRA) to minimize both the risk and uncertainty of Cd exposure from rice consumption. Wollastonite with or without four different phosphates (P) were applied to immobilize soil Cd at paddy fields, and their influences on Cd, essential elements, and amino acids in rice grain were analyzed. Moreover, a bioaccessibility-corrected HRA was conducted to accurately reflect the Cd exposure risk from ingesting these rices. The results showed the co-application of wollastonite and four different P reduced Cd concentrations in rice grain equally, while their impacts on bioaccessibility of Cd in rice during simulated human digestion were inconsistent (53-71%). The HRA based on bioaccessibility of Cd in rice revealed that Cd exposure risk from rice consumption was lowest with the application of wollastonite, followed by the co-application of wollastonite and sodium hexametaphosphate. This work highlights the value of bioaccessibility-corrected HRA for screening the optimal Cd immobilization strategy to achieve safer rice consumption.

The cadmium decontamination and disposal of the harvested cadmium accumulator Amaranthus hypochondriacus L.

The heavy metal accumulated biomass after phytoremediation needs to be decontaminated before disposal. Liquid extraction is commonly used to remove and recycle toxic heavy metals from contaminated biomass. In this study, we examined the cadmium (Cd) removal efficiency using different chemical reagents (hydrochloric acid, nitric acid, sulfuric acid, and ethylenediaminetetraacetic acid disodium) of the post-harvest Amaranthus hypochondriacus L. biomass. The purifications for the extracted liquids and ecological risk assessments for the extracted residues were also investigated. We have found that 77.8% of Cd in stems and 62.1% of Cd in leaves were removed by 0.25 M HCl after 24 h. In addition, K2CO3, KOH, and 4 Å molecular sieve could remove ≥89.0% of Cd in the extracted liquids. Finally, after we returned the extracted residues to the earthworm-incubated soil, the extracted biomass negatively affected the growth (weight loss ≥ 11.0%) and survival (mortality ≥ 33.3%) of Eisenia fetida. It should be noted that earthworms decreased soil available Cd concentrations from 0.14-0.05 mg kg-1 to 0.11-0.04 mg kg-1 and offset the negative effects of the Cd-contaminated biomass on soil microbes. Overall, given the cost of reagents, the Cd removal efficiency, and the ecological risks of the extracted biomass, using 0.25 M HCl for liquid extraction and K2CO3 for purification should be recommended. This work highlights the potential of liquid extraction for immediately and directly removing the Cd from fresh contaminated accumulator biomass and the resource cycling potential of the extracted liquids and biomass after purification.