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1.
J Ultrasound Med ; 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32154606

RESUMO

OBJECTIVES: The anatomic integrity of the female mid urethra is an important factor for urinary continence. However, the associations between the urethral volume and potential affecting factors still remain uncertain. The aim of this study was to investigate the impact of potential factors, including age, height, weight, body mass index (BMI), parity number, delivery mode, and menopause, on the midurethral volume to assist in more-accurate evaluations of urethral anatomy and urinary continence mechanisms in clinical practice. METHODS: A total of 244 women were included in this study. All patients had no incontinence symptoms and underwent transvaginal ultrasound examinations. Detailed histories and demographic data were collected. Urethral volumes were acquired, and volume parameters were measured offline, including the urethral sphincter volume (USV), midurethral complex volume (CV), and inner core volume (ICV). Correlations were analyzed by the Spearman test. For categorical variables, an analysis of variance, Mann-Whitney tests, or Kruskal-Wallis tests were used to estimate associations of potential affecting factors and volumes. RESULTS: The mean age, height, weight, and BMI ± SD of the patients were 35.42 ± 9.88 years, 161.50 ± 4.96 cm, 60.72 ± 11.42 kg, and 23.29 ± 4.20 kg/m2 , respectively. Among potential affecting factors, age had a weak correlation with the USV, CV, and ICV (P = .031, .003, and .004; r = 0.140, 0.193, and 0.187), whereas parity numbers significantly affected the USV, CV, and ICV (P = .014, .021, and .026). The urethral volume became larger with increasing parity. Height (P = .391, .637, and .647), weight (P = .077, .130, and .245), BMI (P = .583, .592, and .643), delivery mode (P = .483, .171, and .104), and menopausal status (P = .611, .717, and .830) had no significant impact on the midurethral volume data (USV, CV, and ICV). CONCLUSIONS: The midurethral volume tended to increase with age and parity in continent women.

2.
Anal Chim Acta ; 1105: 45-55, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32138925

RESUMO

Quantitative analysis of surface-enhanced Raman scattering (SERS) spectra has been a critical step in trace level analysis. In this study, a novel variable selection method called interval combination iterative optimization approach coupled with SIMPLS (ICIOA-SIMPLS) was proposed for simultaneously predicting the volume ratios of various pesticides by quantitative analysis of the SERS spectra of the compounds. Four strategies, including interval selection, model population analysis (MPA), weighted bootstrap sampling (WBS) and soft shrinkage were combined in the current designed ICIOA-SIMPLS approach. Firstly, the SERS spectra were split into a series of equal-width spectral intervals. Secondly, WBS, as a random sampling method was applied based on the initial weights of spectral intervals to generate random combinations of spectral intervals, namely sub-datasets. On this basis, multivariate calibration sub-models were developed by applying SIMPLS followed by MPA to statistically analyze the outputs of sub-models and update the weights of spectral intervals. Finally, using an iterative optimization procedure the optimal spectral interval combination with the lowest root mean squares error of cross-validation (RMSECV) was searched in a soft shrinkage manner. For the sake of investigating the performance of ICIOA-SIMPLS, four methods including SIMPLS, VCPA-SIMPLS, VISSA-SIMPLS and ICIOA-SIMPLS were tested on two groups of SERS spectra for comparison. The findings revealed that the best prediction performance was obtained with ICIOA-SIMPLS. Hence, this proposed method offers a robust and effective variable selection strategy for quantitative analysis of spectroscopic datasets.

3.
Transbound Emerg Dis ; 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32163661

RESUMO

Coronaviruses (CoVs) are found in humans and a wide variety of wild and domestic animals, and of substantial impact on human and animal health. In poultry, the genetic diversity, evolution, distribution and taxonomy of CoVs dominant in birds other than chickens remain enigmatic. In our previous study, we proposed that the CoVs dominant (i.e. mainly circulating) in ducks (DdCoVs) should represent a novel species, which was different from the one represented by the CoVs dominant in chickens (CdCoVs). In this study, we conducted a large-scale surveillance of CoVs in chickens, ducks, geese, pigeons and other birds (quails, sparrows and partridges) using a conserved RT-PCR assay. The surveillance demonstrated that CdCoVs, DdCoVs and the CoVs dominant in pigeons (PdCoVs) belong to different lineages, and they are all prevalent in live poultry markets and the backyard flocks in some regions of China. We further sequenced seven Coronaviridae-wide conserved domains in their replicase polyprotein pp1ab of seven PdCoVs and found that the genetic distances in these domains between PdCoVs and DdCoVs or CdCoVs are large enough to separate PdCoVs into a novel species, which were different from the ones represented by DdCoVs or CdCoVs within the genus Gammacoronavirus, per the species demarcation criterion of International Committee on Taxonomy of Viruses. This report shed novel insight into the genetic diversity, distribution, evolution and taxonomy of avian CoVs.

4.
Nature ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32214235

RESUMO

Single-cell analysis is a valuable tool to dissect cellular heterogeneity in complex systems1. Yet, a comprehensive single-cell atlas has not been achieved for humans. We used single-cell mRNA sequencing to determine the cell-type composition of all major human organs and constructed a scheme for the human cell landscape (HCL). We revealed a single-cell hierarchy for many tissues that have not been well characterised. We established a 'single-cell HCL analysis' pipeline that helps to define human cell identity. Finally, we performed a single-cell comparative analysis of landscapes from both human and mouse to reveal the conserved genetic networks. We found that stem and progenitor cells exhibit strong transcriptomic stochasticity, while the differentiated cells are more distinct. Our study provides a valuable resource for human biology.

5.
Fish Shellfish Immunol ; 100: 161-170, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32135342

RESUMO

Chemokines are small cytokines that are classified into four groups, one of which is called CC chemokines. In the present study, the full-length cDNA of a CCL25 chemokine was identified from black rockfish, Sebastes schlegelii (named as SsCCL25) by EST (expressed sequence tag) analysis. The cDNA of SsCCL25 consisted of a 5-terminal untranslated region (UTR) of 74 bp, a 3-UTR of 882 bp with a poly (A) tail, and an open reading frame (ORF) of 303 bp encoding a polypeptide of 100 amino acids with the putative molecular mass of 11.5 kDa. There was a SCY domain in the deduced amino acid sequence of SsCCL25. The phylogenetic relationships and syntenic analyses provided evidences for the identities of SsCCL25 with CCL25 group. The mRNA transcripts of SsCCL25 were expressed in all detected tissues and dominantly in liver, muscle and gill. Moreover, after Vibrio anguillarum stimulation, the mRNA expression levels of SsCCL25 were significantly up-regulated at 24 h (p < 0.05) in the liver and during 4-8 h (p < 0.05) in the spleen. Recombinant SsCCL25 protein induced chemotaxis of both control and LPS-stimulated peripheral blood leukocytes (PBL) and enhanced their resistance to bacterial infection in a dose-dependent manner. Furthermore, rSsCCL25 showed significant inhibitory effect on V. anguillarum and Edwardsiella tarda growth. All these results collectively indicated that SsCCL25 might contribute to the defense against microbe infection and function as a chemoattractant in black rockfish.

6.
Stem Cell Res ; 44: 101756, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32199281

RESUMO

Waardenburg syndrome (WS) is an inherited auditory-pigmentary syndrome characterized by deafness and pigment abnormalities. Here, we generated an induced pluripotent stem cell (iPSC) line using episomal plasmid vectors from the fibroblasts of an 8-year-old boy affected with WS, caused by a novel mutation in the SOX10 gene (NM_006941.3: c.937_947del; p.Tyr313Argfs*85), with a concurrent hotspot mutation in the GJB2 gene (NM_004004.5:c.235delC; p.Leu79Cysfs*3). The expression of pluripotency markers of the iPSC cell line was verified at both the mRNA and protein levels and the pluripotency state of the cell line was demonstrated by the capability to differentiate into all three germ layers.

7.
FEMS Microbiol Ecol ; 96(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32129838

RESUMO

Biochar, a valuable product from the pyrolysis of agricultural and forestry residues, has been widely applied as soil amendment. However, the effect of different types of biochar on soil microorganisms and associated biochemical processes in paddy soil remains ambiguous. In this study, we investigated the impact of biochars derived from different feedstocks (rice straw, orange peel and bamboo powder) on the dynamics of short-chain fatty acids (SCFAs), iron concentration and bacterial community in paddy soil within 90 days of anaerobic incubation. Results showed that biochar amendment overall inhibited the accumulation of SCFAs while accelerating the Fe(III) reduction process in paddy soil. In addition, 16S rRNA gene sequencing results demonstrated that the α-diversity of the bacterial community significantly decreased in response to biochar amendments at day 1 but was relatively unaffected at the end of incubation, and incubation time was the major driver for the succession of the bacterial community. Furthermore, significant correlations between parameters (e.g. SCFAs and iron concentration) and bacterial taxa (e.g. Clostridia, Syntrophus, Syntrophobacter and Desulfatiglans) were observed. Overall, our findings demonstrated amendment with different types of biochar altered SCFA profile, Fe(III) reduction and bacterial biodiversity in rice paddy soil.

8.
BMC Plant Biol ; 20(1): 114, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32169028

RESUMO

BACKGROUND: Areas with saline soils are sparsely populated and have fragile ecosystems, which severely restricts the sustainable development of local economies. Zoysia grasses are recognized as excellent warm-season turfgrasses worldwide, with high salt tolerance and superior growth in saline-alkali soils. However, the mechanism underlying the salt tolerance of Zoysia species remains unknown. RESULTS: The phenotypic and physiological responses of two contrasting materials, Zoysia japonica Steud. Z004 (salt sensitive) and Z011 (salt tolerant) in response to salt stress were studied. The results show that Z011 was more salt tolerant than was Z004, with the former presenting greater K+/Na+ ratios in both its leaves and roots. To study the molecular mechanisms underlying salt tolerance further, we compared the transcriptomes of the two materials at different time points (0 h, 1 h, 24 h, and 72 h) and from different tissues (leaves and roots) under salt treatment. The 24-h time point and the roots might make significant contributions to the salt tolerance. Moreover, GO and KEGG analyses of different comparisons revealed that the key DEGs participating in the salt-stress response belonged to the hormone pathway, various TF families and the DUF family. CONCLUSIONS: Zoysia salt treatment transcriptome shows the 24-h and roots may make significant contributions to the salt tolerance. The auxin signal transduction family, ABA signal transduction family, WRKY TF family and bHLH TF family may be the most important families in Zoysia salt-stress regulation.

9.
Bioengineered ; 11(1): 386-396, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32172675

RESUMO

Dendrobium cariniferum is a valuable ornamental and medicinal plant rich with polysaccharides, alkaloid, and other bioactive compounds, which are potential raw materials for pharmacological utilization. In this study, an efficient protocol for the rapid propagation of D. cariniferum was developed. By using the tissue culture protocol, the effects of pH, hormone combinations, temperatures, light intensity, culture time protocorm proliferation, seedlings rooting, and accumulation of biomass with bioactive compounds were investigated. The experiments showed that the medium [1/2 MS + activated carbon1.0 g/L+ agar strip 7.5 g/L + sucrose 25 g/L] effectively promoted the germination of D. cariniferum seeds. The optimal culture conditions were found at pH 5.7, temperature 23 ± 2°C, and light intensity of 1000 Lx in the protocorm proliferation stage. Adding 1.5 g/L peptone in the medium effectively promoted the seedling rooting. The optimal culture conditions for accumulation of bioactive compounds (polysaccharides and alkaloids) of seedlings were found at temperature of 25 ± 2°C, light intensity of 1500-2000 Lx after the 60-day (d). Our study constructed a rapid propagation system in vitro for D. cariniferum, as well as the methods for efficient accumulation of active substances in seedling culture, which will serve as guidance for industrial production of D. cariniferum seedlings for both medicinal raw materials and ornamental plants. In addition, our study provided a new idea that we can directly use the high bioactive compound seedlings to extract medicinal components in industry conditions without transferring to the field.

10.
Carbohydr Res ; 490: 107958, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32120022

RESUMO

Rhein is a potential antitumor agent, but the poor water-solubility restricts its clinical applicability. ß-cyclodextrin-drug conjugates provide a possibility to improve the water-solubility of rhein and thereby enhance its bioavailability. A novel ß-cyclodextrin-rhein conjugate (ß-CD-RH) was synthesized by covalently link ß-cyclodextrin with rhein through a 1,8-diamino-3,6-dioxaoctane linker. The structure of ß-CD-RH was characterized by 1H NMR, FT-IR, Maldi-tof MS etc. The inclusion style of ß-CD-RH in water was detected by 2D NMR. The 2D ROESY spectrum provided details of the rhein moiety encapsulated in the ß-CD cavity. The water-solubility of ß-CD-RH is up to 3.24 µmol/mL ß-CD-RH exhibited higher cytotoxicity than rhein and rhein/ß-CD mixture against Hela cells. Our work provides a new way for the preparation of novel ß-CD-drug conjugate.

11.
Nat Genet ; 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32203470

RESUMO

Differences in three-dimensional (3D) chromatin architecture can influence the integrity of topologically associating domains (TADs) and rewire specific enhancer-promoter interactions, impacting gene expression and leading to human disease. Here we investigate the 3D chromatin architecture in T cell acute lymphoblastic leukemia (T-ALL) by using primary human leukemia specimens and examine the dynamic responses of this architecture to pharmacological agents. Systematic integration of matched in situ Hi-C, RNA-seq and CTCF ChIP-seq datasets revealed widespread differences in intra-TAD chromatin interactions and TAD boundary insulation in T-ALL. Our studies identify and focus on a TAD 'fusion' event associated with absence of CTCF-mediated insulation, enabling direct interactions between the MYC promoter and a distal super-enhancer. Moreover, our data also demonstrate that small-molecule inhibitors targeting either oncogenic signal transduction or epigenetic regulation can alter specific 3D interactions found in leukemia. Overall, our study highlights the impact, complexity and dynamic nature of 3D chromatin architecture in human acute leukemia.

12.
Zool Res ; 41(2): 203-207, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32150793

RESUMO

Gap junctions regulate intercellular communication between Sertoli cells and germ cells in male testes and play vital functions in spermatogenesis. Many factors in animal breeding and husbandry can induce oxidative stress, which can impair the testis microenvironment and male animal fertility. However, the underlying mechanisms are largely unknown. Recently, we identified that androgen signals promote the expression of connexin-43 (Cx43), a key component of gap junctions, to regulate spermatogenesis. Thus, we asked whether hyperactive reactive oxygen species (ROS) can impair gap junctions by interfering with Cx43 in porcine testes. Using a porcine Sertoli cell in vitro system, we found that hyperactive ROS caused extensive apoptosis in Sertoli cells, remarkable decrease in Cx43 expression, and failed maintenance of co-cultured spermatogonial stem cells (SSCs), indicating that ROS impaired the function of Sertoli cells and promoted loss of SSCs. This observation provides a possible mechanism for the impact of ROS on fertility of male animals.

13.
Head Neck ; 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32202686

RESUMO

BACKGROUND: Induction chemotherapy followed by concurrent chemoradiotherapy is one of the standards of care for patients with nasopharyngeal carcinoma, but the optimal number of induction cycles is unclear. Here we compared survival data from patients treated with 2 to 4 cycles. METHODS: Patients with nasopharyngeal carcinoma at West China Hospital of Sichuan University between January 2009 and December 2015 were retrospectively analyzed. RESULTS: Six hundred and seventy three patients met eligibility criteria. After a median follow-up of 53 months (interquartile range, 38-74), there was no difference between 2 and 3 cycles in overall survival (88.14% vs 91.24%). But four cycles were associated with worse overall survival (79.12%) and higher incidence of treatment-related toxicities. Multivariate analysis showed that the number of induction cycles and lymph node classification were prognostic factors. CONCLUSIONS: Two and three cycles of induction chemotherapy are associated with similar survival, while four cycles reduce survival and increase treatment-related toxicity in endemic regions.

14.
Artigo em Inglês | MEDLINE | ID: mdl-32208002

RESUMO

Macrophage polarization contributes to obesity-induced insulin resistance. Glucose-regulated protein 94 (GRP94) is an endoplasmic reticulum (ER) chaperon specialized for folding and quality control of secreted and membrane proteins. To determine the role of GRP94 in macrophage polarization and insulin resistance, macrophage-specific GRP94 conditional knockout (KO) mice were generated, and were challenged with high fat diet (HFD). Glucose tolerance, insulin sensitivity, and macrophage composition were compared with control mice. KO mice showed better glucose tolerance and increased insulin sensitivity. Adipose tissues from HFD-KO mice contained lower numbers of M1 macrophages than WT mice, with lower expression of M1 macrophage markers. In vitro, WT adipocytes co-cultured with KO macrophages retained insulin sensitivity whereas those cultured with WT macrophages did not. In addition, compared to WT bone marrow-derived macrophages (BMDMs), BMDMs from GRP94 KO mice exhibited lower expression of M1 macrophage marker genes following stimulation with LPS or IFN-γ, and exhibited partially increased expression of M2 macrophage marker genes following stimulation with interleukin 4 (IL-4). These findings identify GRP94 as a novel regulator of M1 macrophage polarization and insulin resistance and inflammation.

15.
BMC Cardiovasc Disord ; 20(1): 65, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32028896

RESUMO

BACKGROUND: The performance of drug-coated balloons (DCBs) in femoropopliteal interventions has been proven through randomized trials in short lesions and lesions with relatively low proportion of occlusions. There is limited evidence of DCBs in long or occlusive lesions. This study is to investigate the efficacy of the paclitaxel-coated balloon for treatment of long and occlusive femoropopliteal arterial lesions. METHODS: A single-arm trial including 44 femoropopliteal lesions (chronic total occlusion (CTO) plus > 10 cm) treated with DCBs was performed to collect data of average 1-year follow-up. Endpoints contain primary patency, target lesion revascularization (TLR), amelioration of the Rutherford classification, change of ankle brachial index (ABI) and major adverse events. RESULTS: Technical success is 97.7% while device success is 100%. Mean lesion length was 186 ± 86.3 cm. Stent implantation was performed in 13.6%. Cumulative probability of primary patency was 78.8% ± 6.8% at 1 year while that of freedom from TLR was 91.4% ± 4.9%. Rutherford classification improved from average 3.3 ± 1.0 to 2.1 ± 1.4 (p < 0.001) at follow-up with a 72.7% amelioration rate. Ankle-branchial index changed from 0.33 ± 0.40 to 0.67 ± 0.37 (p = 0.002). No major adverse event was observed. CONCLUSION: These results suggest that it is safe and effective to treat long and totally occlusive femoropopliteal artery disease with DCBs. Further studies are demanded to confirm these results.

16.
Cytokine Growth Factor Rev ; 52: 1-14, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32057701

RESUMO

Immune checkpoint inhibitors (ICIs) and immunotherapy have proven to be a transformative therapy for many forms of cancer treatment. While many antibodies targeting the PD-1, PD-L1, and CTLA-4 pathways have been approved for clinical use by the FDA, it is clear that a single ICI is not sufficient to eradicate disease. ICI combination strategies are being extensively investigated to advance cancer treatment to next curative stage. Among the immune checkpoint inhibitors being actively investigated, the potential of VISTA (V-domain Ig suppressor of T cell activation), a unique B7 family member that functions as both ligand and receptor, is being actively pursued. This article summarizes the expression and immunomodulatory effects of VISTA in autoimmune diseases and cancer, and assesses its potential as an additional component of immune checkpoint cancer therapy.

17.
J Am Chem Soc ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32045234

RESUMO

Highly luminescent inks are desirable for various applications such as decorative coating, art painting, and anticounterfeiting, to name a few. However, present inks display low photoluminescent efficiency requiring a strong excitation light to make them glow. Here, we report a highly luminescent ink based on the copper-iodide/1-Propyl-1,4-diazabicyclo[2.2.2]octan-1-ium (Cu4I6(pr-ted)2) hybrid cluster with a quantum efficiency exceeding 98%. Under the interaction between the Cu4I6(pr-ted)2 hybrid cluster and polyvinylpyrrolidone (PVP), the highly luminescent Cu4I6(pr-ted)2/PVP ink can be facilely prepared via the one-pot solution synthesis. The obtained ink exhibits strong green light emission that originates from the efficient phosphorescence of Cu4I6(pr-ted)2 nanocrystals. Attractively, the ink displays high conversion efficiency for the ultraviolet light to bright green light emission due to its wide Stokes shift, implying great potential for anticounterfeiting and luminescent solar concentrator coating.

18.
J Cell Mol Med ; 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32065498

RESUMO

Breast cancer is one leading cause of death in females, especially triple-negative breast cancer (TNBC). Hypoxia is a key feature leading to tumour progression driven by hypoxia-inducible factor (HIF)-1α. The aim is to investigate the mechanism of HIF-1α and signal transducer and activator of transcription-3 (STAT3) interaction and discover a compound to disrupt the interaction in breast cancer cells. The regulation pattern of HIF-1α and STAT3 was analysed in hypoxic TNBC cells and patient samples. The effects of a natural alkaloid, sanguinarine, on HIF-1α and STAT3 colocalization and interaction were evaluated in vitro and mouse xenograft models. We observed strong colocalization of HIF-1α, p-STAT3-Tyr and p-STAT3-Ser in TNBC patient samples. Sanguinarine could inhibit the nuclear colocalization and interaction of HIF-1α with p-STAT3-Tyr and p-STAT3-Ser in vivo and in vitro. Our results may bring insights to the HIF-1α/STAT3 interaction in breast cancers and suggest sanguinarine as a promising candidate for HIF-α/STAT3 inhibition.

19.
Microbiologyopen ; : e997, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32022464

RESUMO

Parsing the relative importance of environmental (recent disturbances) and spatial factors (historical processes) in determining community structure is a core issue in ecology. The Bohai Bay is a typical semi-enclosed bay located in the north of China, surrounding by the metropolitan area with anthropogenic disturbances made it a complex marine coastal system with pollution gradients, where the distributions and determinants of bacterioplankton communities remain unclear. In this study, we collected surface water samples from 19 sites across Bohai Bay at about 100 km scale to investigate the relative roles of local environments and regional spatial factors in shaping bacterioplankton community composition (BCC). The environmental parameters in the sampling region showed gradient change according to the geographic variation. Several abundant OTUs were significantly correlated with the pollution parameters in the studied area, and 16 OTUs of them showed distinct distribution pattern in different polluted regions with obvious geographic segmentation, which indicated the effects of pollution gradient and dispersal limitation on specific taxon. The BCCs did not show obviously clustering effect between different polluted regions, which indicated the complexity for explaining the BCC variation in the studied region. The partial Mantel test revealed stronger spatial effects on beta diversity than those of local environmental factors, which indicated that dispersal limitation accounted more for the beta diversity than environmental heterogeneity. Furthermore, variation partitioning analysis (VPA) conducted by combining the environmental variables, linear trends, and principal coordinates of the variables from neighbor matrices (PCNM) showed that it was the joint effects of environmental and spatial factors contributed to the explained variation of BCC in the studied area. Considering the special human geography characteristics of Bohai Bay, the unmeasured biotic/abiotic factors, stochastic factors, and anthropogenic disturbances may be responsible for the unexplained variation of the BCC.

20.
J Hazard Mater ; 392: 122335, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32092658

RESUMO

Stormwater conveys natural and engineered (nano)-particles, like any other pollutants, from urban areas to water resources. Thus, the use of stormwater green infrastructures (SGI), which infiltrate and treat stormwater, can potentially limit the spread of engineered (nano)-particles in the environment. However, the concentration of engineered (nano)-particles in soil or biofilter media used in SGI has not been measured due to difficulties in distinguishing natural vs. engineered (nano)-particles. This study reports, for the first time, the concentration and size distribution of TiO2 engineered (nano)-particles in soils collected from SGI. The concentrations of TiO2 engineered (nano)-particles were determined by mass balance calculations based on shifts in elemental concentration ratios, i.e., Ti to Nb, Ti to Ta, and Ti to Al in SGI soils relative to natural background elemental ratios. The concentrations of TiO2 engineered (nano)-particles in SGI soils varied between 550 ± 13 and 1800 ± 200 mg kg-1. A small fraction of TiO2 engineered (nano)-particles could be extracted by ultrapure water (UPW) and Na4P2O7; however, the concentration of TiO2 engineered (nano)-particles was higher in the Na4P2O7-extracted suspensions than in UPW-extracted suspensions. The concentration of TiO2 in the nanosize range increased with the increase in extractant (Na4P2O7) volume to soil mass ratio due to the increased disaggregation of soil heteroaggregates. The size distribution of TiO2 engineered (nano)-particles in the < 450 nm Na4P2O7-extracted suspension from one of the SGI soils was determined by asymmetrical flow-field flow fractionation coupled to inductively coupled plasma-mass spectrometer, and was found to vary in the range of 25-200 nm with a modal size of 50 nm. These results demonstrated that the increase in the Ti to natural tracers (e.g., Nb, Ta, and Al) elemental ratios in the SGI soil relative to bulk soil can be used to estimate the concentration of TiO2 engineered (nano)-particles in SGI.

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