Neuronal double-stranded DNA accumulation induced by DNase II deficiency drives tau phosphorylation and neurodegeneration.

BACKGROUND: Deoxyribonuclease 2 (DNase II) plays a key role in clearing cytoplasmic double-stranded DNA (dsDNA). Deficiency of DNase II leads to DNA accumulation in the cytoplasm. Persistent dsDNA in neurons is an early pathological hallmark of senescence and neurodegenerative diseases including Alzheimer's disease (AD). However, it is not clear how DNase II and neuronal cytoplasmic dsDNA influence neuropathogenesis. Tau hyperphosphorylation is a key factor for the pathogenesis of AD. The effect of DNase II and neuronal cytoplasmic dsDNA on neuronal tau hyperphosphorylation remains unclarified. METHODS: The levels of neuronal DNase II and dsDNA in WT and Tau-P301S mice of different ages were measured by immunohistochemistry and immunolabeling, and the levels of DNase II in the plasma of AD patients were measured by ELISA. To investigate the impact of DNase II on tauopathy, the levels of phosphorylated tau, phosphokinase, phosphatase, synaptic proteins, gliosis and proinflammatory cytokines in the brains of neuronal DNase II-deficient WT mice, neuronal DNase II-deficient Tau-P301S mice and neuronal DNase II-overexpressing Tau-P301S mice were evaluated by immunolabeling, immunoblotting or ELISA. Cognitive performance was determined using the Morris water maze test, Y-maze test, novel object recognition test and open field test. RESULTS: The levels of DNase II were significantly decreased in the brains and the plasma of AD patients. DNase II also decreased age-dependently in the neurons of WT and Tau-P301S mice, along with increased dsDNA accumulation in the cytoplasm. The DNA accumulation induced by neuronal DNase II deficiency drove tau phosphorylation by upregulating cyclin-dependent-like kinase-5 (CDK5) and calcium/calmodulin activated protein kinase II (CaMKII) and downregulating phosphatase protein phosphatase 2A (PP2A). Moreover, DNase II knockdown induced and significantly exacerbated neuron loss, neuroinflammation and cognitive deficits in WT and Tau-P301S mice, respectively, while overexpression of neuronal DNase II exhibited therapeutic benefits. CONCLUSIONS: DNase II deficiency and cytoplasmic dsDNA accumulation can initiate tau phosphorylation, suggesting DNase II as a potential therapeutic target for tau-associated disorders.

Mouse serum albumin induces neuronal apoptosis and tauopathies.

The elderly frequently present impaired blood-brain barrier which is closely associated with various neurodegenerative diseases. However, how the albumin, the most abundant protein in the plasma, leaking through the disrupted BBB, contributes to the neuropathology remains poorly understood. We here demonstrated that mouse serum albumin-activated microglia induced astrocytes to A1 phenotype to remarkably increase levels of Elovl1, an astrocytic synthase for very long-chain saturated fatty acids, significantly promoting VLSFAs secretion and causing neuronal lippoapoptosis through endoplasmic reticulum stress response pathway. Moreover, MSA-activated microglia triggered remarkable tau phosphorylation at multiple sites through NLRP3 inflammasome pathway. Intracerebroventricular injection of MSA into the brains of C57BL/6J mice to a similar concentration as in patient brains induced neuronal apoptosis, neuroinflammation, increased tau phosphorylation, and decreased the spatial learning and memory abilities, while Elovl1 knockdown significantly prevented the deleterious effect of MSA. Overall, our study here revealed that MSA induced tau phosphorylation and neuron apoptosis based on MSA-activated microglia and astrocytes, respectively, showing the critical roles of MSA in initiating the occurrence of tauopathies and cognitive decline, and providing potential therapeutic targets for MSA-induced neuropathology in multiple neurodegenerative disorders.

Thrombomodulin reduces α-synuclein generation and ameliorates neuropathology in a mouse model of Parkinson's disease.

The neurotoxic α-synuclein (α-syn) oligomers play an important role in the occurrence and development of Parkinson's disease (PD), but the factors affecting α-syn generation and neurotoxicity remain unclear. We here first found that thrombomodulin (TM) significantly decreased in the plasma of PD patients and brains of A53T α-syn mice, and the increased TM in primary neurons reduced α-syn generation by inhibiting transcription factor p-c-jun production through Erk1/2 signaling pathway. Moreover, TM decreased α-syn neurotoxicity by reducing the levels of oxidative stress and inhibiting PAR1-p53-Bax signaling pathway. In contrast, TM downregulation increased the expression and neurotoxicity of α-syn in primary neurons. When TM plasmids were specifically delivered to neurons in the brains of A53T α-syn mice by adeno-associated virus (AAV), TM significantly reduced α-syn expression and deposition, and ameliorated the neuronal apoptosis, oxidative stress, gliosis and motor deficits in the mouse models, whereas TM knockdown exacerbated these neuropathology and motor dysfunction. Our present findings demonstrate that TM plays a neuroprotective role in PD pathology and symptoms, and it could be a novel therapeutic target in efforts to combat PD. Schematic representation of signaling pathways of TM involved in the expression and neurotoxicity of α-syn. A TM decreased RAGE, and resulting in the lowered production of p-Erk1/2 and p-c-Jun, and finally reduce α-syn generation. α-syn oligomers which formed from monomers increase the expression of p-p38, p53, C-caspase9, C-caspase3 and Bax, decrease the level of Bcl-2, cause mitochondrial damage and lead to oxidative stress, thus inducing neuronal apoptosis. TM can reduce intracellular oxidative stress and inhibit p53-Bax signaling by activating APC and PAR-1. B The binding of α-syn oligomers to TLR4 may induce the expression of IL-1ß, which is subsequently secreted into the extracellular space. This secreted IL-1ß then binds to its receptor, prompting p65 to translocate from the cytoplasm into the nucleus. This translocation downregulates the expression of KLF2, ultimately leading to the suppression of TM expression. By Figdraw.

Astrocytes Excessively Engulf Synapses in a Mouse Model of Alzheimer's Disease.

Synapse loss is one of the most critical features in Alzheimer's disease (AD) and correlates with cognitive decline. Astrocytes mediate synapse elimination through multiple EGF-like domains 10 (MEGF10) pathways in the developing and adult brain to build the precise neural connectivity. However, whether and how astrocytes mediate synapse loss in AD remains unknown. We here find that the phagocytic receptor MEGF10 of astrocytes is significantly increased in vivo and in vitro, which results in excessive engulfment of synapses by astrocytes in APP/PS1 mice. We also observe that the astrocytic lysosomal-associated membrane protein 1 (LAMP1) is significantly elevated, colocalized with the engulfed synaptic puncta in APP/PS1 mice, and astrocytic lysosomes contain more engulfed synaptic puncta in APP/PS1 mice relative to wild type mice. Together, our data provide evidence that astrocytes excessively engulf synapses in APP/PS1 mice, which is mediated by increased MEGF10 and activated lysosomes. The approach targeting synapse engulfment pathway in astrocytes would be a potent therapy for AD.

ArhGAP11A mediates amyloid-ß generation and neuropathology in an Alzheimer's disease-like mouse model.

Amyloid-ß (Aß) plays an important role in the neuropathology of Alzheimer's disease (AD), but some factors promoting Aß generation and Aß oligomer (Aßo) neurotoxicity remain unclear. We here find that the levels of ArhGAP11A, a Ras homology GTPase-activating protein, significantly increase in patients with AD and amyloid precursor protein (APP)/presenilin-1 (PS1) mice. Reducing the ArhGAP11A level in neurons not only inhibits Aß generation by decreasing the expression of APP, PS1, and ß-secretase (BACE1) through the RhoA/ROCK/Erk signaling pathway but also reduces Aßo neurotoxicity by decreasing the expressions of apoptosis-related p53 target genes. In APP/PS1 mice, specific reduction of the ArhGAP11A level in neurons significantly reduces Aß production and plaque deposition and ameliorates neuronal damage, neuroinflammation, and cognitive deficits. Moreover, Aßos enhance ArhGAP11A expression in neurons by activating E2F1, which thus forms a deleterious cycle. Our results demonstrate that ArhGAP11A may be involved in AD pathogenesis and that decreasing ArhGAP11A expression may be a promising therapeutic strategy for AD treatment.

Generalized low levels of serum N-glycans associate with better health status.

Caloric restriction (CR) can prolong life and ameliorate age-related diseases; thus, its molecular basis might provide new insights for finding biomarker and intervention for aging and age-related disease. Glycosylation is an important post-translational modification, which can timely reflect the changes of intracellular state. Serum N-glycosylation was found changed with aging in humans and mice. CR is widely accepted as an effective anti-aging intervention in mice and could affect mouse serum fucosylated N-glycans. However, the effect of CR on the level of global N-glycans remains unknown. In order to explore whether CR affect the level of global N-glycans, we performed a comprehensive serum glycome profiling in mice of 30% calorie restriction group and ad libitum group at 7 time points across 60 weeks by MALDI-TOF-MS. At each time point, the majority of glycans, including galactosylated and high mannose glycans, showed a consistent low level in CR group. Interestingly, O-acetylated sialoglycans presented an upward change different from other derived traits, which is mainly reflected in two biantennary α2,6-linked sialoglycans (H5N4Ge2Ac1, H5N4Ge2Ac2). Liver transcriptome analysis further revealed a decreased transcriptional level of genes involved in N-glycan biosynthesis while increased level of acetyl-CoA production. This finding is consistent with changes in serum N-glycans and O-acetylated sialic acids. Therefore, we provided one possible molecular basis for the beneficial effect of CR from N-glycosylation perspective.

Prediction of Needle Physiological Traits Using UAV Imagery for Breeding Selection of Slash Pine.

Leaf nitrogen (N) content and nonstructural carbohydrate (NSC) content are 2 important physiological indicators that reflect the growth state of trees. Rapid and accurate measurement of these 2 traits multitemporally enables dynamic monitoring of tree growth and efficient tree breeding selection. Traditional methods to monitor N and NSC are time-consuming, are mostly used on a small scale, and are nonrepeatable. In this paper, the performance of unmanned aerial vehicle multispectral imaging was evaluated over 11 months of 2021 on the estimation of canopy N and NSC contents from 383 slash pine trees. Four machine learning methods were compared to generate the optimal model for N and NSC prediction. In addition, the temporal scale of heritable variation for N and NSC was evaluated. The results show that the gradient boosting machine model yields the best prediction results on N and NSC, with R 2 values of 0.60 and 0.65 on the validation set (20%), respectively. The heritability (h 2) of all traits in 11 months ranged from 0 to 0.49, with the highest h 2 for N and NSC found in July and March (0.26 and 0.49, respectively). Finally, 5 families with high N and NSC breeding values were selected. To the best of our knowledge, this is the first study to predict N and NSC contents in trees using time-series unmanned aerial vehicle multispectral imaging and estimating the genetic variation of N and NSC along a temporal scale, which provides more reliable information about the overall performance of families in a breeding program.

Serum IgG N-glycans enable early detection and early relapse prediction of colorectal cancer.

Colorectal cancer (CRC) develops mainly from colorectal advanced adenomas (AA), which are considered precancerous lesions. Novel early diagnostic biomarkers are urgently needed to distinguish CRC and AA from healthy control (HC). Alternative glycosylation of serum IgG has been shown to be closely associated with CRC. We aimed to explore the potential of IgG N-glycan as biomarkers in the early differential diagnosis of CRC. The study population was strictly matched to the exclusion criteria process. Serum IgG N-glycan profiles were analyzed by a robust and reliable relative quantitative method based on ultra-performance liquid chromatography (UPLC). Relative quantification and classification performance of IgG N-glycans were evaluated by Mann-Whitney U tests and ROC curve based on directly detected and derived glycan traits, respectively. Six and 14 directly detected glycan traits were significantly changed in AA and CRC, respectively, compared with HC. GP1 and GP3 were able to accurately distinguish AA from HC for early precancerous lesions screening. GP4 and GP14 provided a high value in discriminating CRC from HC. A novel combined index named GlycoF, including GP1, GP3, GP4, GP14 and CEA was developed to provide a potential early diagnostic biomarker in discriminating simultaneously AA (AUC = 0.847) and CRC (AUC = 0.844) from HC. GlycoF also demonstrated a superior CRC detection rate across CRC all stages and conspicuous prediction ability of risk of relapse. Serum IgG N-glycans analysis provided powerful early screening biomarkers that can efficiently differentiate CRC and AA from HC.

Prognostic and therapeutic significance of microbial cell-free DNA in plasma of people with acute decompensation of cirrhosis.

BACKGROUND & AIMS: Although the effect of bacterial infection on cirrhosis has been well-described, the effect of non-hepatotropic virus (NHV) infection is unknown. This study evaluated the genome fragments of circulating microorganisms using metagenomic next-generation sequencing (mNGS) in individuals with acute decompensation (AD) of cirrhosis, focusing on NHVs, and related the findings to clinical outcomes. METHODS: Plasma mNGS was performed in 129 individuals with AD of cirrhosis in the study cohort. Ten healthy volunteers and 20, 39, and 81 individuals with stable cirrhosis, severe sepsis and hematological malignancies, respectively, were enrolled as controls. Validation assays for human cytomegalovirus (CMV) reactivation were performed in a validation cohort (n = 58) and exploratory treatment was instituted. RESULTS: In the study cohort, 188 microorganisms were detected in 74.4% (96/129) of patients, including viruses (58.0%), bacteria (34.1%), fungi (7.4%) and chlamydia (0.5%). A NHV signature was identified in individuals with AD, and CMV was the most frequent NHV, which correlated with the clinical effect of empirical antibiotic treatment, progression to acute-on-chronic liver failure, and 90-day mortality. The NHV signature in individuals with acute-on-chronic liver failure was similar to that in those with sepsis and hematological malignancies. CMV was detected in 24.1% (14/58) of patients in the validation cohort. Of the 14 cases with detectable CMV by mNGS, nine were further validated by real-time PCR or pp65 antigenemia testing. Three patients with CMV reactivation received ganciclovir therapy in an exploratory manner and experienced clinical resolutions. CONCLUSIONS: The results of this study suggest that NHVs may play a pathogenic role in complicating the course of AD. Further validation is needed to define whether this should be incorporated into the routine management of individuals with AD of cirrhosis. IMPACT AND IMPLICATIONS: A non-hepatotropic virus (NHV) signature, which was similar to that in individuals with sepsis and hematological malignancies, was identified in individuals with acute decompensation of cirrhosis. The detected viral signature had clinical correlates, including clinical efficacy of empirical antibiotic treatment, progression to acute-on-chronic liver failure and short-term mortality. Cytomegalovirus reactivation, which is treatable, may adversely affect clinical outcomes in some individuals with decompensated cirrhosis. Routine screening for NHVs, especially cytomegalovirus, may be useful for the management of individuals with acute decompensation of cirrhosis.

Effects of nitrogen addition and root fungal inoculation on the seedling growth and rhizosphere soil microbial community of Pinus tabulaeformis.

Nitrogen (N) availability is significant in different ecosystems, but the response of forest plant-microbial symbionts to global N deposition remains largely unexplored. In this study, the effects of different N concentration levels on four types of fungi, Suillus granulatus (Sg), Pisolithus tinctorius (Pt), Pleotrichocladium opacum (Po), and Pseudopyrenochaeta sp. (Ps), isolated from the roots of Pinus tabulaeformis were investigated in vitro. Then, the effects of the fungi on the growth performance, nutrient uptake, and rhizosphere soil microbial community structure of P. tabulaeformis under different N addition conditions (0, 40, and 80 kg hm-2 year-1) were examined. The biomass and phytohormone contents of the Sg, Pt and Po strains increased with increasing N concentration, while those of the Ps strain first increased and then decreased. All four fungal strains could effectively colonize the plant roots and form a strain-dependent symbiosis with P. tabulaeformis. Although the effects depended on the fungal species, the growth and root development of inoculated seedlings were higher than those of uninoculated seedlings under N deficiency and normal N supply conditions. However, these positive effects disappeared and even became negative under high N supply conditions. The inoculation of the four fungal strains also showed significant positive effects on the shoot and root nutrient contents of P. tabulaeformis. Fungal inoculation significantly increased different microbial groups and the total soil microorganisms but decreased the microbial diversity under N deficiency stress. In summary, exogenous symbiotic fungal inoculations could increase the growth performance of P. tabulaeformis under N deficiency and normal N supply conditions, but the effects were negative under excessive N addition.

Nitrogen and sulfur fertilizers promote the absorption of lead and cadmium with Salix integra Thunb. by increasing the bioavailability of heavy metals and regulating rhizosphere microbes.

Fertilization is an effective agronomic strategy to improve the efficiency of phytoextraction by Salix integra Thunb. However, the specific effects of the simultaneous application of nitrogen (N) and sulfur (S) fertilizers in the rhizosphere remain unclear. We investigated the bioavailability of lead (Pb) and Cadmium (Cd) along with the microbial metabolic functions and community structure in the rhizosphere soil of S. integra after the application of N (0, 100, and 200 kg·ha-1·year-1) and S (0, 100, and 200 kg·ha-1·year-1) fertilizers for 180 days. The simultaneous application of N and S fertilizers significantly enhanced the absorption of Pb and Cd by S. integra, whereas this effect was not observed for the single application of N or S fertilizer. The contents of acid-soluble Pb and Cd in the rhizosphere soil significantly increased after either single or combined fertilize applications. The microbial metabolic activity was enhanced by the N and S fertilizers, whereas the microbial diversity markedly decreased. The metabolic patterns were mainly affected by the concentration of N fertilizer. The dominant fungi and bacteria were similar under each treatment, although the relative abundances of the dominant and special species differed. Compared to the N200S100 and N200S200 treatments, the N100S100 and N100S200 treatments resulted in fewer pathogenic fungi and more rhizosphere growth-promoting bacteria, which promoted phytoremediation by S. integra. Redundancy analysis indicated that the pH and nitrate content were the key factors affecting the structure of the microbial community. Collectively, the results suggest interactive effects between N and S fertilizers on the rhizosphere soil, providing a potential strategy for plant-microbial remediation by S. integra.

Efficient Immunotherapy of Drug-Free Layered Double Hydroxide Nanoparticles via Neutralizing Excess Acid and Blocking Tumor Cell Autophagy.

Cancer immunotherapy efficacy is largely limited by the suppressive tumor immune microenvironment (TIME) where antitumor immune cells are inhibited and tumor antigens continue to mutate or be lost. To remodel the TIME, we here applied weakly alkaline layered double hydroxide nanoparticles (LDH NPs) to neutralize the excess acid and block autophagy of tumor cells for neoadjuvant cancer immunotherapy. Peritumoral injection of LDH NPs provided a long-term and efficient acid-neutralization in the TIME, blocked the lysosome-mediated autophagy pathway in tumor cells, and increased the levels of antitumor tumor-associated macrophages and T cells. These LDH NPs captured tumor antigens released in the tumor tissues and effectively inhibited the growth of both melanoma and colon tumors in vivo. These findings indicate that LDH NPs, as an immunomodulator and adjuvant, successfully "awaken" and promote the host innate and adaptive immune systems, showing promising potential for solid tumor immunotherapy.

Classification of Toona sinensis Young Leaves Using Machine Learning and UAV-Borne Hyperspectral Imagery.

Rapid and accurate distinction between young and old leaves of Toona sinensis in the wild is of great significance to the selection of T. sinensis varieties and the evaluation of relative yield. In this study, UAV hyperspectral imaging technology was used to obtain canopy hyperspectral data of biennial seedlings of different varieties of T. sinensis to distinguish young and old leaves. Five classification models were trained, namely Random Forest (RF), Artificial Neural Network (ANN), Decision Tree (DT), Partial Least Squares Discriminant Analysis (PLSDA), and Support Vector Machine (SVM). Raw spectra and six preprocessing methods were used to fit the best classification model. Satisfactory accuracy was obtained from all the five models using the raw spectra. The SVM model showed good performance on raw spectra and all preprocessing methods, and yielded higher accuracy, sensitivity, precision, and specificity than other models. In the end, the SVM model based on the raw spectra produced the most reliable and robust prediction results (99.62% accuracy and 99.23% sensitivity on the validation set only, and 100.00% for the rest). Three important spectral regions of 422.7~503.2, 549.2, and 646.2~687.2 nm were found to be highly correlated with the identification of young leaves of T. sinensis. In this study, a fast and effective method for identifying young leaves of T. sinensis was found, which provided a reference for the rapid identification of young leaves of T. sinensis in the wild.

Enabling Breeding Selection for Biomass in Slash Pine Using UAV-Based Imaging.

Traditional methods used to monitor the aboveground biomass (AGB) and belowground biomass (BGB) of slash pine (Pinus elliottii) rely on on-ground measurements, which are time- and cost-consuming and suited only for small spatial scales. In this paper, we successfully applied unmanned aerial vehicle (UAV) integrated with structure from motion (UAV-SfM) data to estimate the tree height, crown area (CA), AGB, and BGB of slash pine for in slash pine breeding plantations sites. The CA of each tree was segmented by using marker-controlled watershed segmentation with a treetop and a set of minimum three meters heights. Moreover, the genetic variation of these traits has been analyzed and employed to estimate heritability (h 2). The results showed a promising correlation between UAV and ground truth data with a range of R 2 from 0.58 to 0.85 at 70 m flying heights and a moderate estimate of h 2 for all traits ranges from 0.13 to 0.47, where site influenced the h 2 value of slash pine trees, where h 2 in site 1 ranged from 0.13~0.25 lower than that in site 2 (range: 0.38~0.47). Similar genetic gains were obtained with both UAV and ground truth data; thus, breeding selection is still possible. The method described in this paper provides faster, more high-throughput, and more cost-effective UAV-SfM surveys to monitor a larger area of breeding plantations than traditional ground surveys while maintaining data accuracy.

Effects of vitamin D with or without calcium on pathological ossification: A retrospective clinical study.

Vitamin D protects against the development and severity of several rheumatic diseases. However, the effect of vitamin D on the pathological ossification associated with rheumatic diseases remains unknown. The present retrospective study analyzed the clinical outcomes of vitamin D without calcium compared with vitamin D with calcium on pathological ossification in joints and ligaments. Data were collected from patients who were diagnosed with osteoarthritis, rheumatoid arthritis or spondylarthritis, and the presence of pathological ossification in joints or ligaments was confirmed by X-ray, computed tomography or magnetic resonance imaging examination. A total of 2,965 patients aged 18-75 years old were included, among who, 1,725 were included in the vitamin D alone group and 1,240 in the vitamin D with calcium group. Vitamin D was administered intramuscularly (300,000 IU) once every 7-10 days, 4-6 times in total. Patients who ingested an oral calcium supplement (1,000 mg/day; ≥5 days/week) were considered the vitamin D with calcium group. The clinical outcome was evaluated based on the imaging changes of pathological ossification, which were classified as alleviation, aggravation and unchanged. The bone mineral density (BMD) was determined, and the calcium concentration in the serum and urine was measured. The results revealed that vitamin D alone alleviated pathological ossification, while vitamin D combined with calcium aggravated pathological ossification in the majority of patients (P<0.0001) independent of disease type and patient age. BMD measurements demonstrated a decreasing trend in the vitamin D alone group, whereas they exhibited an increasing trend in the vitamin D combined with calcium group. The urine calcium concentration increased after vitamin D treatment alone. Therefore, it was concluded that vitamin D exerted both pro-resorptive and anti-resorptive actions on pathological ossification. The bidirectional action of vitamin D on bone metabolism may depend on exogenous calcium supplementation.

Inoculation With Indigenous Rhizosphere Microbes Enhances Aboveground Accumulation of Lead in Salix integra Thunb. by Improving Transport Coefficients.

The application of plant-microbial remediation of heavy metals is restricted by the difficulty of exogenous microbes to form large populations and maintain their long-term remediation efficiency. We therefore investigated the effects of inoculation with indigenous heavy-metal-tolerant rhizosphere microbes on phytoremediation of lead (Pb) by Salix integra. We measured plant physiological indexes and soil Pb bioavailability and conducted widespread targeted metabolome analysis of strains to better understand the mechanisms of enhance Pb accumulation. Growth of Salix integra was improved by both single and co-inoculation treatments with Bacillus sp. and Aspergillus niger, increasing by 14% in co-inoculated plants. Transfer coefficients for Pb, indicating mobility from soil via roots into branches or leaves, were higher following microbial inoculation, showing a more than 100% increase in the co-inoculation treatment over untreated plants. However, Pb accumulation was only enhanced by single inoculation treatments with either Bacillus sp. or Aspergillus niger, being 10% greater in plants inoculated with Bacillus sp. compared with uninoculated controls. Inoculation mainly promoted accumulation of Pb in aboveground plant parts. Superoxide dismutase and catalase enzyme activities as well as the proline content of inoculated plants were enhanced by most treatments. However, soil urease and catalase activities were lower in inoculated plants than controls. Proportions of acid-soluble Pb were 0.34 and 0.41% higher in rhizosphere and bulk soil, respectively, of plants inoculated with Bacillus sp. than in that of uninoculated plants. We identified 410 metabolites from the microbial inoculations, of which more than 50% contributed to heavy metal bioavailability; organic acids, amino acids, and carbohydrates formed the three major metabolite categories. These results suggest that both indigenous Bacillus sp. and Aspergillus niger could be used to assist phytoremediation by enhancing antioxidant defenses of Salix integra and altering Pb bioavailability. We speculate that microbial strains colonized the soil and plants at the same time, with variations in their metabolite profiles reflecting different living conditions. We also need to consider interactions between inocula and the whole microbial community when applying microbial inoculation to promote phytoremediation.

Indigenous Bacteria Have High Potential for Promoting Salix integra Thunb. Remediation of Lead-Contaminated Soil by Adjusting Soil Properties.

Salix integra Thunb., a fast-growing woody plant species, has been used for phytoremediation in recent years. However, little knowledge is available regarding indigenous soil microbial communities associated with the S. integra phytoextraction process. In this study, we used an Illumina MiSeq platform to explore the indigenous microbial composition after planting S. integra at different lead (Pb) contamination levels: no Pb, low Pb treatment (Pb 500 mg kg-1), and high Pb treatment (Pb 1500 mg kg-1). At the same time, the soil properties and their relationship with the bacterial communities were analyzed. The results showed that Pb concentration was highest in the root reaching at 3159.92 ± 138.98 mg kg-1 under the high Pb treatment. Planting S. integra decreased the total Pb concentration by 84.61 and 29.24 mg kg-1, and increased the acid-soluble Pb proportion by 1.0 and 0.75% in the rhizosphere and bulk soil under the low Pb treatment compared with unplanted soil, respectively. However, it occurred only in the rhizosphere soil under the high Pb treatment. The bacterial community structure and microbial metabolism were related to Pb contamination levels and planting of S. integra, while the bacterial diversity was only affected by Pb contamination levels. The dominant microbial species were similar, but their relative abundance shifted in different treatments. Most of the specific bacterial assemblages whose relative abundances were promoted by root activity and/or Pb contamination were suitable for use in plant-microbial combination remediation, especially many genera coming from Proteobacteria. Redundancy analysis (RDA) showed available nitrogen and pH having a significant effect on the bacteria relating to phytoremediation. The results indicated that indigenous bacteria have great potential in the application of combined S. integra-microbe remediation of lead-contaminated soil by adjusting soil properties.

Pharmacokinetics and Comprehensive Analysis of the Tissue Distribution of Eravacycline in Rabbits.

Eravacycline (7-fluoro-9-pyrrolidinoacetamido-6-demethyl-6-deoxytetracycline or TP-434) is a novel, fully synthetic broad-spectrum fluorocycline with potent activity against Gram-positive bacteria, anaerobes, and multidrug-resistant Enterobacteriaceae We characterized the plasma pharmacokinetics of eravacycline and conducted a comprehensive analysis of the eravacycline tissue distribution in rabbits after multiple-day dosing. For single-dose pharmacokinetic analysis, eravacycline was administered to New Zealand White (NZW) rabbits at 1, 2, 4, 8, and 10 mg/kg of body weight intravenously (i.v.) once a day (QD) (n = 20). For multidose pharmacokinetic analysis, eravacycline was administered at 0.5, 1, 2, and 4 mg/kg i.v. QD (n = 20) for 6 days. Eravacycline concentrations in plasma and tissues were analyzed by a liquid chromatography-tandem mass spectrometry assay. Mean areas under the concentration-time curves (AUCs) following a single eravacycline dose ranged from 5.39 µg · h/ml to 183.53 µg · h/ml. Within the multidose study, mean AUCs ranged from 2.53 µg · h/ml to 29.89 µg · h/ml. AUCs correlated linearly within the dosage range (r = 0.97; P = 0.0001). In the cardiopulmonary system, the concentrations were the highest in the lung, followed by the heart > pulmonary alveolar macrophages > bronchoalveolar lavage fluid; for the intra-abdominal system, the concentrations were the highest in bile, followed by the liver > gallbladder > spleen > pancreas; for the renal system, the concentrations were the highest in urine, followed by those in the renal cortex > renal medulla; for the musculoskeletal tissues, the concentrations were the highest in muscle psoas, followed by those in the bone marrow > adipose tissue; for the central nervous system, the concentrations were the highest in cerebrum, followed by those in the aqueous humor > cerebrospinal fluid > choroid > vitreous. The prostate and seminal vesicles demonstrated relatively high mean concentrations. The plasma pharmacokinetic profile of 0.5 to 4 mg/kg in NZW rabbits yields an exposure comparable to that in humans (1 or 2 mg/kg every 12 h) and demonstrates target tissue concentrations in most sites.

Hydrogel loaded with self-assembled dextran sulfate-doxorubicin complexes as a delivery system for chemotherapy.

Standard clinical care for breast cancer includes lumpectomy followed by localized radiotherapy or chemotherapy. However, both therapies cause loss of normal, healthy tissue in addition to tumor tissue, leading to undesirable side effects. In this study, we found that low dose and prolonged treatment with anticancer drug doxorubicin (DOX) can completely eliminate MDA-MB-231 breast cancer cells with low cytotoxicity to NIH 3T3 fibroblasts. We further developed a novel biomaterial-based drug delivery system for controlled and sustained release of low doses of DOX based on self-assembled dextran sulfate (DS)-DOX complexes. We found that adding divalent metal ions in the complex can improve the entrapment efficiency of DOX and prolong DOX release. We encapsulated the DS-DOX complexes into biocompatible, biodegradable, and injectable agarose hydrogel. The hydrogel can be injected into the cavity after lumpectomy for sustained local delivery of low-dose DOX. Cell viability experiments confirmed that this drug delivery system completely eliminated MDA-MB-231 cancer cells while maintaining the viability of NIH 3T3 fibroblasts at the end of treatment. Thus, this novel drug delivery system represents a promising approach for local chemotherapy to improve locoregional control of breast cancer.

[Soil microorganisms, nutrients and enzyme activity of Larix kaempferi plantation under different ages in mountainous region of eastern Liaoning Province, China].

We studied the community of soil microorganisms, enzyme activity and soil nutrients under 11-, 20-, 34-and 47-year-old Larix kaempferi plantations in mountainous region of eastern Liaoning Province to discuss the soil biological properties of L. kaempferi plantations of different stand ages and their relationships with soil nutrients. The results showed that the indexes reflecting soil micro-organisms, enzyme activity and soil nutrients of L. kaempferi plantations were the highest under the 11- or 47-year-old stand and the lowest in the 20- or 34-year-old stand. Soil productivity appeared in a decline trend with the increasing stand age, and the changes of soil microbial community structure and enzyme activity were responsive to soil degradation. The difference of fungi community was more noticeable than that of bacteria community among the plantations with different stand ages. The results of CCA showed soil nutrient and pH had no effect on seasonal difference of community structure, but had effects on community, structure among different stand ages. The total N, organic carbon, C/N, available nitrogen, exchangeable Mg2+ and pH had greater effects on bacteria community, while available P, total K and pH had greater effect on fungi community among different age forests. The main T-RFs of bacteria and fungi had higher correlation with N and P, and the fungi community had higher correlation with organic carbon and K than bacteria community. The microor-ganism community of the 11- and 47-year-old stands had greater correlation with soil nutrients and enzyme activity than that of 20- and 34-year-old stands. Consequently, soil organisms, in particular soil fungi, could be used to indicate soil degradation.