Automatic soft-tissue analysis on orthodontic frontal and lateral facial photographs based on deep learning.

BACKGROUND: To establish the automatic soft-tissue analysis model based on deep learning that performs landmark detection and measurement calculations on orthodontic facial photographs to achieve a more comprehensive quantitative evaluation of soft tissues. METHODS: A total of 578 frontal photographs and 450 lateral photographs of orthodontic patients were collected to construct datasets. All images were manually annotated by two orthodontists with 43 frontal-image landmarks and 17 lateral-image landmarks. Automatic landmark detection models were established, which consisted of a high-resolution network, a feature fusion module based on depthwise separable convolution, and a prediction model based on pixel shuffle. Ten measurements for frontal images and eight measurements for lateral images were defined. Test sets were used to evaluate the model performance, respectively. The mean radial error of landmarks and measurement error were calculated and statistically analysed to evaluate their reliability. RESULTS: The mean radial error was 14.44 ± 17.20 pixels for the landmarks in the frontal images and 13.48 ± 17.12 pixels for the landmarks in the lateral images. There was no statistically significant difference between the model prediction and manual annotation measurements except for the mid facial-lower facial height index. A total of 14 measurements had a high consistency. CONCLUSION: Based on deep learning, we established automatic soft-tissue analysis models for orthodontic facial photographs that can automatically detect 43 frontal-image landmarks and 17 lateral-image landmarks while performing comprehensive soft-tissue measurements. The models can assist orthodontists in efficient and accurate quantitative soft-tissue evaluation for clinical application.

[Rapid determination of 15 N-nitrosamines in air-dried yak meat using one-step QuEChERS-gas chromatography-triple quadrupole mass spectrometry].

A method based on gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) coupled with one-step QuEChERS technique was developed for the simultaneous determination of 15 N-nitrosamines in air-dried yak meat. The hydration volume, extraction solvent, extracting salt, and cleaning material were optimized according to the characteristics of the N-nitrosamines and sample matrix. The optimized conditions were as follows: 10 mL of purified water for sample hydration, acetonitrile as the extraction solvent for the sample after hydration, 4.0 g of anhydrous MgSO4 and 1.0 g of NaCl as extracting salts, 500 mg of MgSO4+25 mg of C18+50 mg of PSA as cleaning materials. Favorable recoveries of the 15 N-nitrosamines were obtained when the extraction solution was incompletely dried. Thus, the final extract was dried to below 0.5 mL under a mild nitrogen stream and then redissolved to 0.5 mL with acetonitrile. After filtration, 200 µL of the sample was transferred to an autosampler vial for GC-MS/MS analysis. The 15 N-nitrosamines were determined using GC-MS/MS on a DB-HeavyWAX column (30 m×0.25 mm×0.25 µm) with an electron impact ion source in multiple-reaction monitoring (MRM) mode, and quantified using an external standard method. Under the optimized experimental conditions, the results showed that the calibration curves exhibited good linearities for the 15 N-nitrosamines, with correlation coefficients (r2) greater than 0.9990. The limits of detection (LODs) and the limits of quantification (LOQs) ranged from 0.05 to 0.20 µg/kg and from 0.10 to 0.50 µg/kg, respectively. At spiked levels of 1LOQ, 2LOQ, and 10LOQ, the average recoveries were 79.4%-102.1%, 80.6%-109.5%, and 83.0%-110.6%, respectively, and the relative standard deviations were in the range of 0.8%-16.0%. The low matrix effects of the 15 N-nitrosamines indicated the high sensitivity of the proposed method. The method was applied to detect representative commercial air-dried yak meat samples obtained using different processing techniques. Seven N-nitrosamines, including N-nitrosodimethylamine, N-nitrosodiisobutylamine, N-nitrosodibutylamine, N-methyl-N-phenylnitrous amide, N-ethyl-N-nitrosoaniline, N-nitrosopyrrolidine, and N-nitrosodiphenylamine were detected in all samples. The average contents of the seven N-nitrosamines was 0.08-20.18 µg/kg. The detection rates and average contents of the N-nitrosamines in cooked air-dried yak meat samples were higher than those in traditional raw air-dried yak meat samples. Compared with the manual QuEChERS method, the one-step QuEChERS method developed integrated the extraction and clean-up procedures into one single run, and the detection efficiency was considerably improved. The developed method is simple, rapid, highly sensitive, and insusceptible to human errors. Thus, it is useful for the determination of N-nitrosamines in air-dried yak meat and can be extended to the qualitative and quantitative analysis of N-nitrosamines in other meat products. It also provides method support and a data reference for the general determination of N-nitrosamines, which is of great significance for food safety.

STSN-Net: Simultaneous Tooth Segmentation and Numbering Method in Crowded Environments with Deep Learning.

Accurate tooth segmentation and numbering are the cornerstones of efficient automatic dental diagnosis and treatment. In this paper, a multitask learning architecture has been proposed for accurate tooth segmentation and numbering in panoramic X-ray images. A graph convolution network was applied for the automatic annotation of the target region, a modified convolutional neural network-based detection subnetwork (DSN) was used for tooth recognition and boundary regression, and an effective region segmentation subnetwork (RSSN) was used for region segmentation. The features extracted using RSSN and DSN were fused to optimize the quality of boundary regression, which provided impressive results for multiple evaluation metrics. Specifically, the proposed framework achieved a top F1 score of 0.9849, a top Dice metric score of 0.9629, and an mAP (IOU = 0.5) score of 0.9810. This framework holds great promise for enhancing the clinical efficiency of dentists in tooth segmentation and numbering tasks.

Three-dimensional finite element analysis on the effects of maxillary protraction with an individual titanium plate at multiple directions and locations.

Objective: : A three-dimensional-printed individual titanium plate was applied for maxillary protraction to eliminate side effects and obtain the maximum skeletal effect. This study aimed to explore the stress distribution characteristics of sutures during maxillary protraction using individual titanium plates in various directions and locations. Methods: : A protraction force of 500 g per side was applied at forward and downward angles between 0° and 60° with respect to the Frankfort horizontal plane, after which the titanium plate was moved 2 and 4 mm upward and downward, respectively. Changes in sutures with multiple protraction directions and various miniplate heights were quantified to analyze their impact on the maxillofacial bone. Results: : Protraction angle of 0-30° with respect to the Frankfort horizontal plane exhibited a tendency for counterclockwise rotation in the maxilla. At a 40° protraction angle, translational motion was observed in the maxilla, whereas protraction angles of 50-60° tended to induce clockwise rotation in the maxilla. Enhanced protraction efficiency at the lower edge of the pyriform aperture was associated with increased height of individual titanium plates. Conclusions: : Various protraction directions are suitable for patients with different types of vertical bone surfaces. Furthermore, when the titanium plate was positioned lower, the protraction force exhibited an increase.

Roles of sulfate-reducing bacteria in sustaining the diversity and stability of marine bacterial community.

Microbes play central roles in ocean food webs and global biogeochemical processes. Yet, the information available regarding the highly diverse bacterial communities in these systems is not comprehensive. Here we investigated the diversity, assembly process, and species coexistence frequency of bacterial communities in seawater and sediment across ∼600 km of the eastern Chinese marginal seas using 16S rRNA gene amplicon sequencing. Our analyses showed that compared with seawater, bacterial communities in sediment possessed higher diversity and experienced tight phylogenetic distribution. Neutral model analysis showed that the relative contribution of stochastic processes to the assembly process of bacterial communities in sediment was lower than that in seawater. Functional prediction results showed that sulfate-reducing bacteria (SRB) were enriched in the core bacterial sub-communities. The bacterial diversities of both sediment and seawater were positively associated with the relative abundance of SRB. Co-occurrence analysis showed that bacteria in seawater exhibited a more complex interaction network and closer co-occurrence relationships than those in sediment. The SRB of seawater were centrally located in the network and played an essential role in sustaining the complex network. In addition, further analysis indicated that the SRB of seawater helped maintain the high stability of the bacterial network. Overall, this study provided further comprehensive information regarding the characteristics of bacterial communities in the ocean, and provides new insights into keystone taxa and their roles in sustaining microbial diversity and stability in ocean.

Coffea arabica Extract Attenuates Atopic Dermatitis-like Skin Lesions by Regulating NLRP3 Inflammasome Expression and Skin Barrier Functions.

Atopic dermatitis (AD) is a common skin disease worldwide. The major causes of AD are skin barrier defects, immune dysfunction, and oxidative stress. In this study, we investigated the anti-oxidation and anti-inflammation effects of Coffea arabica extract (CAE) and its regulation of the skin barrier and immune functions in AD. In vitro experiments revealed that CAE decreased the reactive oxygen species levels and inhibited the translocation of nuclear factor-κB (NF-κB), further reducing the secretion of interleukin (IL)-1ß and IL-6 induced by interferon-γ (IFN-γ)/tumor necrosis factor-α (TNF-α). Moreover, CAE decreased IFN-γ/TNF-α-induced NLR family pyrin domain-containing 3 (NLRP3), caspase-1, high-mobility group box 1 (HMGB1), and receptor for advanced glycation end products (RAGE) expression levels. It also restored the protein levels of skin barrier function-related markers including filaggrin and claudin-1. In vivo experiments revealed that CAE not only reduced the redness of the backs of mice caused by 2,4-dinitrochlorobenzene (DNCB) but also reduced the levels of pro-inflammatory factors in their skin. CAE also reduced transepidermal water loss (TEWL) and immune cell infiltration in DNCB-treated mice. Overall, CAE exerted anti-oxidation and anti-inflammation effects and ameliorated skin barrier dysfunction, suggesting its potential as an active ingredient for AD treatment.

Metavirome of 31 tick species provides a compendium of 1,801 RNA virus genomes.

The increasing prevalence and expanding distribution of tick-borne viruses globally have raised health concerns, but the full repertoire of the tick virome has not been assessed. We sequenced the meta-transcriptomes of 31 different tick species in the Ixodidae and Argasidae families from across mainland China, and identified 724 RNA viruses with distinctive virome compositions among genera. A total of 1,801 assembled and complete or nearly complete viral genomes revealed an extensive diversity of genome architectures of tick-associated viruses, highlighting ticks as a reservoir of RNA viruses. We examined the phylogenies of different virus families to investigate virome evolution and found that the most diverse tick-associated viruses are positive-strand RNA virus families that demonstrate more ancient divergence than other arboviruses. Tick-specific viruses are often associated with only a few tick species, whereas virus clades that can infect vertebrates are found in a wider range of tick species. We hypothesize that tick viruses can exhibit both 'specialist' and 'generalist' evolutionary trends. We hope that our virome dataset will enable much-needed research on vertebrate-pathogenic tick-associated viruses.

Automatic analysis of lateral cephalograms based on high-resolution net.

INTRODUCTION: Cephalometric analysis is essential in orthodontic treatment, and it is progressing toward automatic cephalometric analysis. This study aimed to establish a cephalometric landmark detection model on the basis of a high-resolution net and improve the accuracy with high resolution. METHODS: A total of 2000 lateral cephalograms were collected to construct a dataset, and the number of target landmarks was 51. A high-resolution network model was applied to the landmark detection task. Four models were trained by adjusting different input resolutions to choose the most suitable resolution. A test set consisting of 300 lateral cephalograms was used for evaluation. The model was evaluated from the error size and distribution of each landmark. RESULTS: After 200 epochs of training, a landmark detection model was established. Under different resolutions of the input image, the mean model radial error decreased initially and then increased. At 680 × 920 pixels resolution, the minimum error and the highest detection success rate were obtained. The mean radial error was 1.08 ± 0.87 mm. The detection success rates of 2.0 mm, 2.5 mm, 3.0 mm, and 4.0 mm were 89.00%, 94.00%, 96.33%, and 98.67%, respectively. The mean radial errors of 22 landmarks were <1 mm, and the errors of other landmarks were <2 mm except for the pterion. The error distribution of landmarks followed a certain pattern. CONCLUSIONS: An automatic landmark detection model based on a high-resolution net was established to recognize 51 landmarks. The model showed high detection accuracy, which provides a basis for further measurement application.

Fermented Taiwanofungus camphoratus Extract Ameliorates Psoriasis-Associated Response in HaCaT Cells via Modulating NF-𝜠B and mTOR Pathways.

Psoriasis is a chronic autoimmune disease, and until now, it remains an incurable disease. Therefore, the development of new drugs or agents that ameliorate the disease will have marketing potential. Taiwanofungus camphoratus (TC) is a specific fungus in Taiwan. It is demonstrated to have anticancer, anti-inflammation, and hepatoprotective effects. However, the effects of TC fermented extract on psoriasis are under investigation. In this research, we studied the ability of TC on antioxidative activity and the efficacy of TC on interleukin-17 (IL-17A)-induced intracellular oxidative stress, inflammation-relative, and proliferation-relative protein expression in human keratinocytes. The results of a DPPH radical scavenging assay, reducing power assay, and hydroxyl peroxide inhibition assay indicated that TC has a potent antioxidant ability. Furthermore, TC could reduce IL-17A-induced intracellular ROS generation and restore the NADPH level. In the investigation of pathogenesis, we discovered TC could regulate inflammatory and cell proliferation pathways via p-IKKα/p-p65 and p-mTOR/p-p70S6k signaling pathways in human keratinocytes. In conclusion, TC showed characteristics such as antioxidant, anti-inflammatory, and anti-psoriatic-associated responses. It is expected to be developed as a candidate for oxidative-stress-induced skin disorders or psoriasis treatment.

Heat shock protein 90 inhibitor 17-AAG down-regulates thymidine phosphorylase expression and potentiates the cytotoxic effect of tamoxifen and erlotinib in human lung squamous carcinoma cells.

Elevated thymidine phosphorylase (TP) levels, a key enzyme in the pyrimidine nucleoside salvage pathway, in cancer cells, are related to a poor prognosis in a variety of cancers. Heat shock protein 90 (Hsp90) is a ubiquitous molecular chaperone that is involved in the stabilization and maturation of many oncogenic proteins. The aim of this study is to elucidate whether Hsp90 inhibitor 17-AAG could enhance tamoxifen- and erlotinib-induced cytotoxicity in nonsmall cell lung cancer (NSCLC) cells via modulating TP expression in two squamous NSCLC cell lines, H520 and H1703. We found that 17-AAG reduced TP expression via inactivating the MKK1/2-ERK1/2-mitogen-activated protein kinase (MAPK) pathway. TP knockdown with siRNA or ERK1/2 MAPK inactivation with the pharmacological inhibitor U0126 could enhance the cytotoxic and growth inhibitory effects of 17-AAG. In contrast, MKK1-CA or MKK2-CA (a constitutively active form of MKK1/2) vector-enforced expression could reduce the cytotoxic and cell growth inhibitory effects of 17-AAG. Furthermore, 17-AAG enhanced the cytotoxic and cell growth inhibitory effects of tamoxifen and erlotinib in NSCLC cells, which were associated with TP expression downregulation and MKK1/2-ERK1/2 signal inactivation. Taken together, Hsp90 inhibition downregulates TP, enhancing the tamoxifen- and erlotinib-induced cytotoxicity in H520 and H1703 cells.

First description of the mitogenome and phylogeny:Aedes vexansand Ochlerotatus caspius of the Tribe Aedini (Diptera: Culicidae).

Culicidae, the mosquito family, includes more than 3600 species subdivided into the subfamilies Anophelinae and Culicinae. One-third of mosquitoes belong to the Aedini tribe, which is subordinate to the subfamily Culicinae, which comprises common vectors of viral zoonoses. The tribe of Aedini is extremely diverse in morphology and geographical distribution and has high ecological and medical significance. However, knowledge about the systematics of the Aedini tribe is still limited owing to its large population and the similar morphological characteristics of its species. This study provides the first description of the complete mitochondrial (mt) genome sequence of Aedes vexans and Ochlerotatus caspius belonging to the Aedini tribe. The mt genomes of A. vexans and O. caspius are circular molecules that are 15,861 bp and 15,954 bp in size, with AT contents of 78.54% and 79.36%, respectively. Both the circular mt genomes comprise 37 functional subunits, including 13 protein-coding genes (PCGs), two ribosomal RNA genes, 22 transfer RNA genes (tRNAs), and a control region (also known as the AT-rich region). The most common start codons are ATT/ATG, apart from cox1 (TCG) and nad5 (GTG), while TAA is the termination codon for all PCGs. All tRNAs have a typical clover leaf structure, except tRNA Ser1. Phylogenetic analysis of the concatenated, aligned amino acid sequences of the 13 PCGs showed that A. vexans gathered with Aedes sp. in a sister taxon, and O. caspius gathered with Ochlerotatus sp. in a sister taxon. The findings from the present study support the concept of monophyly of all groups, ratify the current taxonomic classification, and provide vital molecular marker resources for further studies of the taxonomy, population genetics, and systematics of the Aedini tribe.

Multiple biochemical indices and metabolomics of Clonorchis sinensis provide a novel interpretation of biomarkers.

BACKGROUND: Clonorchiasis, an infectious disease caused by the liver fluke Clonorchis sinensis, may lead to the development of liver and gallbladder diseases, and even cholangiocarcinoma (CCA). However, the pathogenesis, host-pathogen interaction, and diagnostic markers for clonorchiasis remain unclear. METHODS: Eighteen rabbits were randomly divided into control group (n = 9) and C. sinensis-infected group (n = 9), and their plasma samples were collected at 7, 14, 28, and 63 days post-infection (dpi). Biochemical indices and metabolites in different infection periods were detected. A non-targeted ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) approach was employed to investigate the metabolic profiles of plasma in rabbits, and related metabolic pathways of differential metabolites and correlation between candidate biochemical indices and differential metabolites were analyzed. Finally, the candidate biomarkers were verified with human samples using a targeted metabolomics method. RESULTS: The result of biochemical indices indicated C. sinensis infection would affect the liver function biochemical indices, especially alanine aminotransferase, aspartate transaminase (AST), glutamyl transpeptidase (GGT), total bile acid, high-density lipoprotein, and cholinesterase. The metabonomic results showed that 58, 212, 23, and 21 differential metabolites were identified in different phases of the infection. Multivariate statistical analysis of differential metabolites revealed distinct metabolic signatures during different phases of infection, with most of these signatures being observed at 14 dpi, which mainly influences the amino acid metabolisms. For metabolites and biochemical indices, AST, GGT, hypoxanthine, L-pipecolic acid, and D-glucuronate represented potential noninvasive biomarkers for the diagnosis of C. sinensis (P < 0.05 and AUC > 0.8). Furthermore, GGT and D-glucuronate levels were positively correlated with the infection (r(28) = 0.98, P < 0.0001) and showed excellent diagnostic performance (AUC = 0.972; 95% confidence interval, 0.921 to 1.000). CONCLUSIONS: The present results provide new insights into plasma metabolic changes in rabbits during C. sinensis infection, and the potential biomarker may be used for developing an effective method to diagnose clonorchiasis in the future.

The complete mitochondrial genome of Prosthogonimus cuneatus and Prosthogonimus pellucidus (Trematoda: Prosthogonimidae), their features and phylogenetic relationships in the superfamily Microphalloidea.

Prosthogonimus cuneatus and Prosthogonimus pellucidus (Trematoda: Prosthogonimidae) are common flukes of poultry and other birds which can cause severe impacts on animal health and losses to the poultry industry. However, there are limited studies on the molecular epidemiology, population genetics, and systematics of Prosthogonimus species. In the present study, the complete mitochondrial (mt) genomes of P. cuneatus and P. pellucidus were determined to be 14,829 bp and 15,013 bp in length, respectively. Both mt genomes contain 12 protein-coding genes (PCGs) (cox1-3, nad1-6, nad4L, cytb, and atp6), 22 transfer RNA genes, two ribosomal RNA genes, and one non-coding region. Our comparative analysis shows that the atp6 genes of P. cuneatus and P. pellucidus are longer than any previously published atp6 genes of other trematodes. The lengths of the atp6 genes of P. cuneatus and P. pellucidus in this study seem unusual, and should therefore be studied further. The mt genes of P. cuneatus and P. pellucidus are transcribed in the same direction, and the gene arrangements are identical to those of Plagiorchis maculosus, Tamerlania zarudnyi, and Tanaisia sp., but different from those of Eurytrema pancreaticum, Dicrocoelium chinensis, and Brachycladium goliath. The mt genome A + T contents of P. cuneatus and P. pellucidus are 64.47% and 65.34%, respectively. In the 12 PCGs, ATG is the most common initiation codon, whereas TAG is the most common termination codon. The sequence identity of the same 12 PCGs among the eight trematodes (P. cuneatus, P. pellucidus, Pl. maculosus, D. chinensis, E. pancreaticum, B. goliath, T. zarudnyi, Tanaisia sp.) of Xiphidiata are 55.5%-81.7% at the nucleotide level and 43.9%-82.5% at the amino acid level. The nucleotide similarities among the complete mt genomes of the eight trematodes range from 54.1%-81.5%. Phylogenetic analysis based on the aligned concatenated amino acid sequences of the 12 PCGs shows that P. cuneatus and P. pellucidus cluster together and are sister to T. zarudnyi and Tanaisia sp., and this clade is more closely related to E. pancreaticum, Dicrocoelium spp. and Lyperosomum longicauda in the family Dicrocoeliidae, than it is to species in the families Plagiorchiidae and Brachycladiidae. These are the first reported complete mt genomes of Prosthogonimidae, and these data will provide additional molecular resources for further studies of Prosthogonimidae taxonomy, population genetics, and systematics.

Enhanced nitrate, manganese, and phenol removal by polyvinyl alcohol/sodium alginate with biochar gel beads immobilized bioreactor: Performance, mechanism, and bacterial diversity.

Water pollutants, such as nitrate, heavy metals, and organics have attracted attention due to their harms to environmental and biological health. A novel polyvinyl alcohol/sodium alginate with biochar (PVA/SA@biochar) gel beads immobilized bioreactor was established to remove nitrate, manganese, and phenol. The optimum conditions for preparing gel beads were studied by response surface methodology (RSM). Notably, the removal efficiencies of nitrate, Mn(II), and phenol were 94.64, 72.74, and 93.97% at C/N of 2.0; the concentrations of Mn(II) and phenol were 20 and 1 mg L-1, respectively. Moreover, addition of different concentrations of phenol significantly affected the components of dissolved organic matter, bacterial activity, and bioreactor performance. The biological manganese oxide (BMO) with three-dimensional petal-type structure produced during Mn(II) oxidation showed excellent adsorption capacity. The removal of phenol relied on a combination of biological action and adsorption processes. High-throughput analysis showed that Zoogloea sp. was the predominant bacterial group.

Complete mitochondrial genome of Dermanyssus gallinae (Arthropoda: Dermanyssidae) isolate from China.

The complete mitochondrial genome of Dermanyssus gallinae isolated from China is reported for the first time in this study. Its entire mitogenome is 16, 184 bp in length, contained 13 protein-coding genes, 2 ribosomal RNA genes, 21 transfer RNA genes, and 1 non-coding region. The phylogenetic analysis by maximum likelihood method show that D. gallinae isolated from China is in the same clade with the genus of Psoroptes. This is the first complete mitochondrial genome of D. gallinae.

Phenol and 17ß-estradiol removal by Zoogloea sp. MFQ7 and in-situ generated biogenic manganese oxides: Performance, kinetics and mechanism.

The pollution of multifarious pollutants such as heavy metal, organic compounds, and nitrate are a hot research topic at present. In this study, the functions of Zoogloea sp. MFQ7 and its biological precipitation formed during bacterial manganese oxidation on the removal of phenol and 17ß-estradiol (E2) were investigated. Strain MFQ7, a manganese-oxidizing bacteria, can remove 98.34% of phenol under pH of 7.1, a temperature of 30 â„ƒ and Mn2+ concentration of 24.34 mg L-1, additionally, the optimum E2 removal by strain MFQ7 was 100.00% at pH of 7.1, temperature of 28 â„ƒ and Mn2+ concentration of 28.45 mg L-1 by using response surface methodology (RSM) based on Box-Behnken design (BBD) model. The maximum adsorption capacity of bio-precipitation for phenol and E2 was 201.15 mg g-1 and 65.90 mg g-1, respectively. Furthermore, adsorption kinetics and isotherms analysis, XPS, FTIR spectra, Mn(III) trapping experiments elucidated chemical adsorption and Mn(III) oxidation contribute to the removal of phenol and E2 by biogenic manganese oxides. These findings indicated that the adsorption and oxidation of manganese are expected to be one of the effective means to remove these typical organic pollutants containing phenol and E2.

Bioaugmented removal of 17ß-estradiol, nitrate and Mn(II) by polypyrrole@corn cob immobilized bioreactor: Performance optimization, mechanism, and microbial community response.

The coexistence of nitrate and endocrine substances (EDCs) in groundwater is of global concern. Herein, an efficient and stable polypyrrole@corn cob (PPy@Corn cob) bioreactor immobilized with Zoogloea sp. was designed for the simultaneous removal of 17ß-estradiol (E2), nitrate and Mn(II). After 225 days of continuous operation, the optimal operating parameters and enhanced removal mechanism were explored, also the long-term toxicity and microbial communities response mechanisms under E2 stress were comprehensively evaluated. The results showed that the removal efficiencies of E2, nitrate, and Mn(II) were 84.21, 82.96, and 47.91%, respectively, at the optimal operating conditions with hydraulic retention time (HRT) of 8 h, pH of 6.5 and Mn(II) concentration of 20 mg L-1. Further increased of initial E2 (2 and 3 mg L-1) resulted in the inhibiting effect of denitrification and manganese oxidation, but excellent E2 removal efficiencies maintained, which were associated with the formation and continuous accumulation of biomanganese oxides (BMO). Characterization analysis of biological precipitation demonstrated that adsorption and redox conversion on the BMO surface played key roles in the removal of E2. In addition, different levels of E2 exposure are decisive factors in community evolution, and bioaugmented bacterial communities with Zoogloea as the core group can dynamically adapt to E2 stress. This study offers the possibility to better utilize microbial metabolism and to advance opportunities that depend on microbial physiology and material characterization applications.

Denitrification performance of nitrate-dependent ferrous (Fe2+) oxidizing Aquabacterium sp. XL4: Adsorption mechanisms of bio-precipitation of phenol and estradiol.

In this study, a nitrate-dependent ferrous (Fe2+) oxidizing strain under anaerobic conditions was selected and identified as XL4, which belongs to Aquabacterium. The Box-Behnken design (BBD) was used to optimize the growth conditions of strain XL4, and the nitrate removal efficiency of strain XL4 (with 10% inoculation dosage, v/v) could reach 91.41% under the conditions of 30.34 â„ƒ, pH of 6.91, and Fe2+ concentration of 19.69 mg L-1. The results of Fluorescence excitation-emission matrix spectra (EEM) revealed that the intensity of soluble microbial products (SMP), aromatic proteins and the fulvic-like materials were obvious difference under different Fe2+ concentration, pH, and temperature. X-ray diffraction (XRD) data confirmed that the main components of bio-precipitation were Fe3O4 and FeO(OH), which were believed to be responsible for the adsorption of phenol and estradiol. Furthermore, the maximum adsorption capacity of bio-precipitation for phenol and estradiol under the optimal conditions were 192.6 and 65.4 mg g-1, respectively. On the other hand, the adsorption process of phenol and estradiol by bio-precipitation confirmed to the pseudo-second-order and Langmuir model, which shows that the adsorption process is chemical adsorption and occurs on the uniform surface.

Efficient removal of nitrate, manganese, and tetracycline in a novel loofah immobilized bioreactor: Performance, microbial diversity, and functional genes.

The remediation of multiple pollutants in water, for instance, nitrate, heavy metals, and antibiotics is urgent and necessary for the global water resources protection. Herein, a modified loofah bioreactor was designed for simultaneous denitrification, manganese (Mn) oxidation, and tetracycline (TC) removal. The maximum removal efficiencies of NO3--N (91.97%), Mn(II) (71.25%), and TC (57.39%) were achieved at a hydraulic retention time (HRT) of 9 h, Mn(II) concentration of 20 mg L-1, and TC concentration of 1 mg L-1. SEM and XRD were carried out to characterize the bioprecipitation in the operation of bioreactor. TC addition affected the gaseous denitrification products, dissolved organic matter, as well as reduced the OTU in the bioreactor. The Zoogloea were regarded as the dominant species in the microbial community and played an essential role in the operation of bioreactor. Metagenomic analysis proved the great potential for denitrification, manganese oxidation, and antibiotic removal of loofah bioreactor.

Insights into the mechanism of Mn(II)-based autotrophic denitrification: Performance, genomic, and metabonomics.

The technologies for groundwater nitrate pollution treatment have drawn increasing global attention. As for autotrophic denitrification (AD), most researches aimed to the mixed microbial culture bioreactors, the mechanism of AD by purely cultured bacteria has not been fully investigated yet. Here, denitrification ability, bacterial activity, and dissolved organic matter evolution of Cupriavidus sp. HY129 in both AD and heterotrophic denitrification (HD) were studied. Genomic analysis and microbial metabolomic analysis were applied to explore the mechanism of AD and the difference and intrinsic factors in AD and HD. The results revealed that HD resulted in higher denitrification efficiency and biomass compared to AD and the bacteria preferred to synthesize humic-like proteins to maintain the progress of AD. Bacteria carry out Mn oxidation outside the bacteria cell and transfer electrons into the cell for AD. Cupriavidus sp. HY129 genome has critical metabolic pathways in both autotrophic and heterotrophic conditions, as well as the MCO gene for mediating the Mn oxidation. Energy metabolism pathways were the most significantly differences between AD and HD. Moreover, sphingolipid metabolism and mineral absorption metabolism were the most essential pathways in the autotrophic process to maintain the normal physiological activities and Mn transfer. The results explored the differences between AD and HD pathways in the same bacteria for the first time and provided new insight into understanding the metabolic characteristics of different denitrification, which provide useful information to the global nitrogen cycle and nitrate pollution treatment.