Fibroblast alignment and matrix remodeling induced by a stiffness gradient in a skin-derived extracellular matrix hydrogel.

Large skin injuries heal as scars. Stiffness gradually increases from normal skin to scar tissue (20x higher), due to excessive deposition and crosslinking of extracellular matrix (ECM) mostly produced by (myo)fibroblasts. Using a custom mold, skin-derived ECM hydrogels (dECM) were UV crosslinked after diffusion of ruthenium (Ru) to produce a Ru-dECM gradient hydrogel. The Ru diffusion gradient equates to a stiffness gradient and models physiology of the scarred skin. Crosslinking in Ru-dECM hydrogels results in a 23-fold increase in stiffness from a stiffness similar to that of normal skin. Collagen fiber density increases in a stiffness-dependent fashion while stress relaxation also alters, with one additional Maxwell element necessary for characterizing Ru-dECM. Alignment of fibroblasts encapsulated in hydrogels suggests that the stiffness gradient directs fibroblasts to orientate at ∼45 ° in regions below 120 kPa. In areas above 120 kPa, fibroblasts decrease the stiffness prior to adjusting their orientation. Furthermore, fibroblasts remodel their surrounding ECM in a gradient-dependent fashion, with rearrangement of cell-surrounding ECM in high-stiffness areas, and formation of interlaced collagen bundles in low-stiffness areas. Overall, this study shows that fibroblasts remodel their local environment to generate an optimal ECM mechanical and topographical environment. STATEMENT OF SIGNIFICANCE: This study developed a versatile in vitro model with a gradient stiffness using skin-derived ECM hydrogel with unchanged biochemical environment. Using Ruthenium crosslinking, a 20-fold stiffness increase was achieved as observed in fibrotic skin. The interaction between fibroblasts and matrix depends on changes in the matrix stiffness. The stiffness gradient directed the alignment of fibroblasts with ∼45° in regions with≤ 120 kPa. The cells in regions with the higher stiffness decreased stiffness first and then oriented themselves. Furthermore, fibroblasts remodeled surrounding ECM and regulated its mechanics in a gradient-dependent fashion to reach an optimal condition. Our study highlights the dynamic interplay between cells and surrounding matrix, shedding light on potential mechanisms and strategies to target scar formation and remodeling.

Physical Properties and Biochemical Composition of Extracellular Matrix-Derived Hydrogels Dictate Vascularization Potential in an Organ-Dependent Fashion.

The inherent extracellular matrix (ECM) originating from a specific tissue impacts the process of vascularization, specifically vascular network formation (VNF) orchestrated by endothelial cells (ECs). The specific contribution toward these processes of ECM from highly disparate organs such as the skin and lungs remains a relatively unexplored area. In this study, we compared VNF and ECM remodeling mediated by microvascular ECs within gel, lung, and combinations thereof (hybrid) ECM hydrogels. Irrespective of the EC source, the skin-derived ECM hydrogel exhibited a higher propensity to drive and support VNF compared to both lung and hybrid ECM hydrogels. There were distinct disparities in the physical properties of the three types of hydrogels, including viscoelastic properties and complex architectural configurations, including fiber diameter, pore area, and numbers among the fibers. The hybrid ECM hydrogel properties were unique and not the sum of the component ECM parts. Furthermore, cellular ECM remodeling responses varied with skin ECM hydrogels promoting matrix metalloproteinase 1 (MMP1) secretion, while hybrid ECM hydrogels exhibited increased MMP9, fibronectin, and collagen IV deposition. Principal component analysis (PCA) indicated that the influence of a gel's mechanical properties on VNF was stronger than the biochemical composition. These data indicate that the organ-specific properties of an ECM dictate its capacity to support VNF, while intriguingly showing that ECs respond to more than just the biochemical constituents of an ECM. The study suggests potential applications in regenerative medicine by strategically selecting ECM origin or combinations to manipulate vascularization, offering promising prospects for enhancing wound healing through pro-regenerative interventions.

Screening of low-Cd-accumulating and Cd-remediating oilseed rape varieties using a newly indicator system for risk management of Cd-contaminated agricultural land.

Although oilseed rape is frequently used as an alternative planting crop in the phytoremediation of cadmium (Cd)-contaminated agricultural land, methods for screening excellent oilseed rape varieties in this regard are inadequate. Herein, we developed a screening method that incorporates Cd accumulation, distribution, and removal, economic output, adaptability to Cd-contaminated agricultural land, and trace element variation. A Cd-adaptability index (Cd-AI) based on 10 agronomic traits was used to measure the adaptability of varieties to Cd-contaminated agricultural land. Moreover, to simplify the evaluation of adaptability, yield, biomass, and pod number with high weightings were selected to construct a discriminant function for Cd-contaminated agricultural land adaptability (correctly classified 94.20%). In a 2 year field trial, we evaluated 225 oilseed rape varieties, among which we identified two promising low-Cd-accumulating and two Cd-remediating varieties. For the low-Cd-accumulating varieties (HuYou17 and DeXingYou558), we obtained grain bioaccumulation factor (BAF) values of 0.07 and 0.08, BAFsoil-stalk values of <1, and economic outputs of RMB 25,054 and 32,292 yuan hm-2, respectively. Similarly, the Cd-remediating varieties (ZaoZa8 and YuYou61) were characterized by BAFsoil-stalk values of 4.65 and 3.61, BAFsoil-grain values of 0.16 and 0.16, Cd removals of 69.02 and 58.25 g hm-2, and economic outputs of RMB 31,189 and 24,962 yuan hm-2, respectively. Compared with the control variety, we detected lower uptakes of multiple trace elements (3-43%) in the low-Cd-accumulating varieties, whereas the Cd-remediating varieties were characterized by 15.40% and 8.30% increases in the accumulation of magnesium and zinc, respectively. Our findings augment the evaluation indices used for evaluating oilseed rape varieties and provide valuable insights from the perspectives of varietal screening and promotional application. The effective varieties identified have application potential for safe production and the remediation of agricultural land without interrupting annual agricultural production, and provide an economically sustainable approach for the utilization of Cd-contaminated agricultural land.

Fibroblasts alter the physical properties of dermal ECM-derived hydrogels to create a pro-angiogenic microenvironment.

This study aimed to investigate the impact of fibroblasts (MRC-5) on the extracellular matrix (ECM) microenvironment of endothelial cells (ECs) during the vascularization of skin-derived ECM hydrogel in vitro. Two types of ECs were studied: human dermal microvascular endothelial cells (HMEC) and human pulmonary microvascular endothelial cells (HPMEC). Results showed that the presence of MRC-5 fibroblasts increased the stiffness of the hydrogel and led to larger fiber diameters and increased porosity. Extensive collagen fiber remodeling occurred in the ECM hydrogel with MRC-5 fibroblasts. Additionally, higher levels of fibulin-1 and fibronectin were deposited in the hydrogel when co-cultured with MRC-5 fibroblasts. These findings suggest that MRC-5 fibroblasts play a role in modifying the ECM microenvironment, promoting vascularization through dynamic ECM remodeling.

Kawasaki Disease Associated Acute Abdomen: Most Require No Surgery.

Objective: To summarize the clinical features and treatment experiences of patients with Kawasaki disease (KD)-associated acute abdomen (KD-AA). Methods: We conducted a retrospective case-control study of patients with KD-AA treated at our hospital between January 2006 and November 2022. Results: Of the 917 children with KD, 43 (4.7%) presented with AA. Of these, 33 with complete information were included in the KD-AA group. Patients with KD-AA were significantly older, with higher neutrophil rate, C-reactive protein, procalcitonin, and alanine transaminase levels and lower hemoglobin, albumin, and serum sodium levels. Additionally, more patients with KD-AA presented with aseptic meningitis and KD shock syndrome than those with KD alone (all p<0.05). The two groups did not differ in the incidence of intravenous immunoglobulin (IVIG) resistance, incomplete KD, or coronary artery abnormalities. All patients received aspirin and IVIG therapy, with nine receiving a second dose of IVIG and 11 receiving corticosteroids. Only two patients with KD-AA underwent surgery, and the prognosis of all patients with KD-AA was good. Conclusion: KD-AA should be suspected in febrile children with abdominal symptoms. Prompt diagnosis of KD-AA is important for early effective treatment to avoid unnecessary surgical harm. KD, complicated by acute abdomen, has a good prognosis.

A meta-analysis of closed reduction percutaneous pinning and open reduction with pin fixation of pediatric humeral lateral condylar fracture.

Objective: To compare the effectiveness and safety of closed reduction percutaneous pinning vs. open reduction with pin fixation to treat the pediatric humeral lateral condylar fracture. Methods: Studies comparing closed reduction percutaneous pinning vs. open reduction with pin fixation for treating pediatric lateral humeral condyle fractures were found by searching Pubmed, Embase, the Cochrane Library, and Web of Science databases, including randomized/non-randomized controlled, retrospective case-control, and prospective cohort studies. Furthermore, quality evaluation and data retrieval were conducted after the literature review. A meta-analysis was performed using RevMan 5.4 software to compare both groups' outcome measures. Results: This Meta-analysis incorporated eight studies with 856 cases. The Meta-analysis found no significant difference in functional outcomes, superficial infection, deep infection, poor fracture union, avascular necrosis of the humeral capitulum, or lateral spur formation between groups. However, the status of unaesthetic scars in the closed reduction percutaneous pinning group was superior. Conclusions: For pediatric humeral lateral condylar fracture surgical therapy, the efficacy and safety of closed reduction percutaneous pinning vs. open reduction with pin fixation were not significantly different; closed reduction percutaneous pinning offered the benefit of eliminating unaesthetic scar. However, further high-quality research is required to verify the conclusions of this Meta-analysis. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/#myprospero, identifier CRD42023392451.

Migration and transformation of Cd in four crop rotation systems and their potential for remediation of Cd-contaminated farmland in southern China.

A crop rotation system combining agricultural production with phytoremediation is an economical and sustainable method of remediation of cadmium (Cd)-contaminated farmland. This study focuses on migration and transformation of Cd in rotation systems and the influencing factors. In a two-year field experiment, four rotation systems were evaluated: traditional rice and oilseed rape (TRO), low-Cd rice and oilseed rape (LRO), maize and oilseed rape (MO), and soybean and oilseed rape (SO). Oilseed rape is a remediation plant in rotation systems. Compared to 2020, the grain Cd concentrations of traditional rice, low-Cd rice, and maize in 2021 decreased by 73.8%, 65.7%, and 24.0% (below the safety limits), respectively. However, soybean increased by 71.4%. The LRO system featured the highest oil content of rapeseed (about 50%) and economic output/input ratio (1.34). Removal efficiency of total Cd in soil was 10.03% (TRO) > 8.3% (LRO) > 5.32% (SO) > 3.21% (MO). Crop uptake of Cd was influenced by bioavailability of soil Cd, and soil environmental factors regulated the bioavailable Cd. Redundancy analysis (RDA) indicated that soil nitrate­nitrogen (NO3--N) had a dominant impact on bioavailable Cd in soil, with variance contributions of 56.7% for paddy-upland (TRO and LRO) and 53.5% for dryland (MO and SO) rotation systems. The difference reflected that ammonium N (NH4+-N) was a secondary factor in paddy-upland rotations, while it was the available phosphorus (P) in dryland rotations, with variance contributions of 10.4% and 24.3%, respectively. The comprehensive evaluation of crop safety, production, economic benefits, and remediation efficiency revealed that the LRO system was efficient and more acceptable to local farmers, providing a new direction for the utilization and remediation of Cd-contaminated farmland.

Comparison of mothers' perceptions of hunger cues in 3-month-old infant under different feeding methods.

BACKGROUND: Mothers' perception of infant hunger cues is a critical content of responsive feeding, which is central to the promotion of early childhood development. However, only a few studies have examined responsive feeding in China, especially lacking the studies on perceptions of infant hunger cues. Consider the cultural differences, the aim of this study was to describe the perceptions of infant hunger cues of Chinese mothers for infants aged 3 months, and explore the relationship between maternal perceptions of infant hunger cues and different feeding methods. METHODS: A cross-sectional study was conducted with a sample of 326 mothers of healthy 3-month-old infants, including 188 exclusive breastfeeding (EBF) mothers and 138 formula feeding (FF) mothers. It was implemented in four provincial and municipal maternal and child health hospitals. The mothers' perceptions of infant hunger cues were surveyed by self-reporting questionnaires. Chi-square tests and logistic analysis were applied to analyze the differences in maternal perceptions of infant hunger cues, including the number of hunger cues and the specific cues, between EBF group and FF group by controlling sociodemographic variables and the daily nursing indicators. RESULTS: We found that a higher proportion of EBF mothers could perceive multiple hunger cues (≥ 2) than FF mothers (66.5% vs.55.1%). For specific cues, the EBF mothers had higher perceptions of infant's "hand sucking" (67.6% vs. 53.6%) and "moving head frantically from side to side" (34.6% vs. 23.9%), all p < 0.05. Regression analysis revealed that EBF might support mothers to perceive infant hunger cues than FF mothers, with the number of infant hunger cues (OR = 1.70, 95% CI: 1.01-2.85), "hand sucking" (OR = 1.72, 95% CI: 1.04-2.87), "moving head frantically from side to side" (OR = 2.07, 95% CI: 1.19-3.62). The number of infant hunger cues perceived by mothers was also associated with their educational level and family structure. CONCLUSION: EBF mothers of 3-month-old infants may be more likely to perceive infant hunger cues than FF mothers in China. It is necessary to increase the health education about infant hunger and satiety cues to caregivers in China, especially among mothers with lower education levels, mothers living in nuclear families, and FF mothers.

Safe usage of Cd-polluted paddy fields using alkaline Si-rich compound amendment: Effect and mechanism.

A low-cost practical technology is urgently needed to minimize cadmium (Cd) pollution in rice in many parts of the world. In the present study, we elucidated the effects and mechanisms of four alkaline compound materials via field experiments in southern China. The results indicated that these two alkaline Si-rich compound materials (AF-SC, alkaline fertilizer compounded with Si-Ca mineral powder; AF-SS, AF compounded with Si-Se mineral powder) could achieve multi-objective gains by simultaneously reducing grain Cd, increasing yield and improving soil quality at a lower cost. The grain Cd content was decreased by an average of about 75% in two field sites, which even ensured safe grain production in areas with medium Cd pollution. The rice yield was increased by a range of 6.7%-21.0% for different varieties and sites. Moreover, the materials abated soil acidification with the increase of 0.36-0.62 pH units, increased the contents of available P and available Si, subsequently reducing available Cd content in soils. Structural equation model and regression analysis showed that the alkaline environment provided by the alkaline components in compound materials effectively inhibited the formation of Fe/Mn plaques on the root surface, reducing the uptake of Cd from the environment. In addition, the decrease in grain Cd was also attributed to the inhibition of Cd translocation from root to stem, mainly caused by the increase of available Si. These findings reveal that the base application of such alkaline Si-rich compound materials is a viable solution for the remediation of Cd-polluted paddy fields in south China.

Mapping Chinese annual gross primary productivity with eddy covariance measurements and machine learning.

Annual gross primary productivity (AGPP) is the basis for grain production and terrestrial carbon sequestration. Mapping regional AGPP from site measurements provides methodological support for analysing AGPP spatiotemporal variations thereby ensures regional food security and mitigates climate change. Based on 641 site-year eddy covariance measuring AGPP from China, we built an AGPP mapping scheme based on its formation and selected the optimal mapping way, which was conducted through analysing the predicting performances of divergent mapping tools, variable combinations, and mapping approaches in predicting observed AGPP variations. The reasonability of the selected optimal scheme was confirmed by assessing the consistency between its generating AGPP and previous products in spatiotemporal variations and total amount. Random forest regression tree explained 85 % of observed AGPP variations, outperforming other machine learning algorithms and classical statistical methods. Variable combinations containing climate, soil, and biological factors showed superior performance to other variable combinations. Mapping AGPP through predicting AGPP per leaf area (PAGPP) explained 86 % of AGPP variations, which was superior to other approaches. The optimal scheme was thus using a random forest regression tree, combining climate, soil, and biological variables, and predicting PAGPP. The optimal scheme generating AGPP of Chinese terrestrial ecosystems decreased from southeast to northwest, which was highly consistent with previous products. The interannual trend and interannual variation of our generating AGPP showed a decreasing trend from east to west and from southeast to northwest, respectively, which was consistent with data-oriented products. The mean total amount of generated AGPP was 7.03 ± 0.45 PgC yr-1 falling into the range of previous works. Considering the consistency between the generated AGPP and previous products, our optimal mapping way was suitable for mapping AGPP from site measurements. Our results provided a methodological support for mapping regional AGPP and other fluxes.

Precise and differentiated solutions for safe usage of Cd-polluted paddy fields at regional scale in southern China: Technical methods and field validation.

Cadmium (Cd) contamination in rice grains has become a severe issue worldwide. This study aims to explore feasible technologies applicable to different risk lands and develop a practical solution for safe rice production at a regional scale. Despite inconsistent field conditions in the whole region, various foliar fertilizers could effectively decrease grain Cd content by 20.4-41.6 % and were capable of producing safe grains in low/medium-risk areas. At high-risk sites, foliage dressing coupled with alkaline fertilizers significantly reduced Cd accumulation and increased grain compliance rate to 95.0 %. The cost analysis and questionnaire survey showed the above technologies are low-cost, eco-friendly, and highly acceptable in real-world scenarios. The classification results by conditional inference tree (CIT) for CK and FS scenarios indicated grain Cd content is closely related to the interaction effects of soil Cd and pH. On these bases, the whole area was divided spatially into three different risk zones, and each zone matched a feasible method for safe production, subsequently developing a precise and differentiated solution. The estimation results demonstrate it can effectively improve the precision level of safe utilization of regional polluted lands and save more than half of the total cost, providing a new idea for regional Cd-polluted paddy fields management strategies.

Differential roles for lysyl oxidase (like), family members in chronic obstructive pulmonary disease; from gene and protein expression to function.

Chronic obstructive pulmonary disease (COPD) is characterized by long-term airflow obstruction with cigarette smoke as a key risk factor. Extracellular matrix (ECM) alterations in COPD may lead to small airway wall fibrosis. Altered collagen cross-linking, potentially mediated by the lysyl oxidase (LO) family of enzymes (LOX, LOXL1-4), orchestrates disturbed ECM homeostasis. In this study, we investigated the effects of smoking status and presence and severity of COPD on LOs gene and protein expression in the airways and the impact of LOs inhibition on airway contraction in an ex vivo mouse model. We used gene expression data from bronchial brushings, airway smooth muscle (ASM) cells in vitro and immunohistochemistry in lung tissue to assess smoke- and COPD-associated differences in LOs gene and protein expression in the small airways. We found higher LOX expression in current- compared to ex-smokers and higher LOXL1 expression in COPD compared to non-COPD patients. LOX and LOXL2 expression were upregulated in COPD ASM cells treated with cigarette smoke extract. LOXL1 and LOXL2 protein levels were higher in small airways from current- compared to non-smokers. In COPD patients, higher LOXL1 and lower LOX protein levels were observed, but no differences for LOXL2, LOXL3, and LOXL4 protein were detected in small airways. Inhibiting LOs activity increased airway contraction in murine lung slices. COPD-associated changes in LOs, in particular LOX and LOXL1, may be related to smoking and contribute to impaired airway function, providing potential novel targets for preventing or treating small airways changes in COPD.

An in vitro model of fibrosis using crosslinked native extracellular matrix-derived hydrogels to modulate biomechanics without changing composition.

Extracellular matrix (ECM) is a dynamic network of proteins, proteoglycans and glycosaminoglycans, providing structure to the tissue and biochemical and biomechanical instructions to the resident cells. In fibrosis, the composition and the organization of the ECM are altered, and these changes influence cellular behaviour. Biochemical (i. e. protein composition) and biomechanical changes in ECM take place simultaneously in vivo. Investigating these changes individually in vitro to examine their (patho)physiological effects has been difficult. In this study, we generated an in vitro model to reflect the altered mechanics of a fibrotic microenvironment through applying fibre crosslinking via ruthenium/sodium persulfate crosslinking on native lung ECM-derived hydrogels. Crosslinking of the hydrogels without changing the biochemical composition of the ECM resulted in increased stiffness and decreased viscoelastic stress relaxation. The altered stress relaxation behaviour was explained using a generalized Maxwell model. Fibre analysis of the hydrogels showed that crosslinked hydrogels had a higher percentage of matrix with a high density and a shorter average fibre length. Fibroblasts seeded on ruthenium-crosslinked lung ECM-derived hydrogels showed myofibroblastic differentiation with a loss of spindle-like morphology together with greater α-smooth muscle actin (α-SMA) expression, increased nuclear area and circularity without any decrease in the viability, compared with the fibroblasts seeded on the native lung-derived ECM hydrogels. In summary, ruthenium crosslinking of native ECM-derived hydrogels provides an exciting opportunity to alter the biomechanical properties of the ECM-derived hydrogels while maintaining the protein composition of the ECM to study the influence of mechanics during fibrotic lung diseases. STATEMENT OF SIGNIFICANCE: Fibrotic lung disease is characterized by changes in composition and excessive deposition of extracellular matrix (ECM). ECM fibre structure also changes due to crosslinking, which results in mechanical changes. Separating the changes in composition and mechanical properties has been difficult to date. In this study, we developed an in vitro model that allows alteration of the mechanical changes alone by applying fibre crosslinking in native lung ECM-derived hydrogels. Characterisations of the crosslinked hydrogels indicated the model mimicked mechanical properties of fibrotic lung tissue and reflected altered fibre organisation. This ECM-based fibrosis model provides a method to preserve the native protein composition while altering the mechanical properties providing an important tool, not only for lung but also other organ fibrosis.

The characterization of organic nitrogen and sulfur functional groups in coals after biomethane production.

To study the change characteristics of nitrogen and sulfur functional types in the raw coal and coal residues after anaerobic fermentation, three different rank coals from Baiyinhua mine (BY coal), Qianqiu mine (QQ coal), and Malan mine (ML coal) in China were collected and treated with methanogenic microorganisms, then X-ray photoelectron spectroscopy (XPS) was used to test the nitrogen and sulfur functional types in raw coals and coal residues. The results show that the pyrrolic nitrogen (N-5) and aromatic sulfur are the main nitrogen type and sulfur type in three coals. The N-5 increases by 17.42% in BY coal residue and decreases by 2.37% and 8.51% in QQ and ML coal residues, respectively. The pyridinic nitrogen (N-6) in BY, QQ, and ML coal residues decreases by 2.18%, 5.44%, and 2.75%, respectively. The aromatic sulfur increases by 2.13%, 3.14%, and 4.02% in BY, QQ, and ML coal residues, respectively. The aliphatic sulfur has obvious changes in BY and QQ coal residues with the increment of 9.17% and decrement of 11.64%, respectively. The results reveal that the nitrogen and sulfur types have changed in the coal residues after the biomethane production, and the instable types such as N-5 and aliphatic sulfur have obvious changes in the low-rank BY and QQ coals. The research provides a sight to the changes about nitrogen and sulfur types after biomethane yield and more deep thoughts about the clean and effective utilization of coals.

The complete mitochondrial genome of the bagworm from a tea plantation in China, Eumeta variegata (Lepidoptera: Psychidae).

The mitochondrial (mt) genome of Eumeta variegata Snellen (Psychidae) has been sequenced and annotated. The mt genome has a total length of 15,793 bp, consisting of 13 protein-coding genes, 22 tRNA, two rRNA genes, and an AT-rich control region (GenBank accession no. MN242985). The nucleotide composition was extremely AT-rich, and the AT content is 81.57%. The gene order is consistent with other sequenced mt genome of moths and butterflies from Ditrysia. The sequence similarity of E. variegate mt genomes between the specimen of China and South Korea is 98.38%, whereas the similarity between the specimen of China and Japan is 90.61%. The sequence of PCGs and rRNAs among different specimens are similar, and many differences are detected at the region of A + T-rich region and the tRNA block 'ARNS1EF'.

Phytoexclusion of heavy metals using low heavy metal accumulating cultivars: A green technology.

Heavy metal (HM) pollution of farmland is a serious problem worldwide and consumption of HM-contaminated food products poses significant public health risks. Phytoexclusion using low HM accumulating cultivars (LACs) is a promising and practical technology to mitigate the risk of HM contamination of agricultural products grown in polluted soils, and does not alter cultivation practices, is easy to apply, and is economical. This review provides an overview of the major scientific advances accomplished in the field of LACs worldwide. The LACs concept and identification criteria are presented, and the known LACs among currently cultivated grain crops and vegetables are re-evaluated. The low HM accumulation by LACs is affected by crop ecophysiological features and soil physicochemical characteristics. Taking low Cd accumulating cultivars as an example, it is known that they can efficiently exclude Cd from entering their edible parts in three ways: 1) decrease in root Cd uptake by reducing organic acids secretion in the rhizosphere and transport protein production; 2) restriction of Cd translocation from roots to shoots via enhanced Cd retention in the cell wall and Cd sequestration in vacuoles; and 3) reduction in Cd translocation from shoots to grains by limiting Cd redirection and remobilization mediated through nodes. We propose an LAC application strategy focused on LACs and optimized to work with other agronomic measures according to the classification of HM risk level for LACs, providing a cost-effective and practical solution for safe utilization of large areas of farmland polluted with low to moderate levels of HMs.

Study on the bio-oil characterization and heavy metals distribution during the aqueous phase recycling in the hydrothermal liquefaction of As-enriched Pteris vittata L.

The hydrothermal liquefaction (HTL) of As enriched Pteris vittata L. (PVL, hyper-accumulator biomass) was performed with the recycled aqueous phase as reaction medium, aiming to dispose the biomass with high water content and produce high-quality bio-oil. After three times of aqueous phase recycling at 275 °C, 30 min, the bio-oil yield increased to 30.32% from 21.54% and the higher heating value (HHV, 28.51 MJ/kg) of the bio-oil was higher than that of the bio-oil from HTL with pure water (26.80 MJ/kg). The main compounds detected in bio-oils were phenols, ketones, hydrocarbons, and aldehydes. Acetic acid (17.21-24.77 mg/mL) was dominant in the aqueous phases, resulting in the low pH (4.31-4.89). The heavy metals (Cu, Pb, Zn, Cd) mainly remained in bio-char whereas As was transferred to aqueous phase. Thus, HTL by aqueous phase recycling could be a promising way for PVL treatment to obtain high-quality bio-oil and arsenic recovery.

Effects of statherin on the biological properties of titanium metals subjected to different surface modification.

The failure of dental implants is usually caused by bacteria infection, poor bioactivity and biocompatibility. It is a common phenomenon clinically. Statherin, a salivary protein, plays a crucial role of mediator between materials and cells/bacteria. However, the conformation of statherin might be changed by the implants in vivo. In this study, we investigated the effects of statherin on the bioactivities, antibacterial abilities and biocompatibilities of the titanium metals and the reaction mechanism. We found that the conformation of statherin was mainly influenced by surface composition, surface structure, surface roughness, surface hydrophilia and Ti-OH groups of materials. Statherin could decrease the cell biocompatibility of the titanium metals including pure titanium (PT), anodic oxidation (AO), sandblasting and etching (SLA) and plasma spraying hydroxyapatite (HA) coating in HGF cell experiments, regulate the bio-mineralization ability of HA coating in SBF, and enhance the antibacterial properties of PT and HA coating. This study revealed that surface properties of materials could change the conformation of statherin, which influenced the bioactivities, antibacterial properties and biocompatibilities of the materials in return.

Effects of adding selenium on different remediation measures of paddy fields with slight-moderate cadmium contamination.

A number of remediation measures have been used in paddy fields to alleviate serious cadmium (Cd) contamination, which may pose a public health risk through the food chain. In this study, a field trial was conducted in paddy fields with slight-moderate Cd contamination to investigate the remediation effects of combined remediation measures (CRMs), including the use of Cd-safe rice (Oryza sativa L.) cultivars, water management modes (WMMs), lime application (LA), soil amendment application (SAA), and foliar silicon (Si) fertilizers. Two groups of field trials were designed including CRMs with selenium (Se) and without selenium (non-Se) application. The results show that soil measures (LA + SAA) can increase the soil pH by 0.99 and decrease the soil DTPA-extracted Cd content by 34.19% (p < 0.05). All measures used in the present study significantly decreased the Cd content in husked rice and yield, except for the WMMs; the CRMs achieved the best results, and Se application enhanced the effects of all measures. This study shows that CRMs significantly decreased the Cd content in husked rice by 58.10%; this value increased to 72.69% after Se application (p < 0.05). These results provide useful information for selecting remediation measures in paddy fields with slight-moderate Cd contamination.