Regulation of the Function of T Follicular Helper Cells and B Cells in Type 1 Diabetes Mellitus by the OX40/OX40L Axis.

OBJECTIVE/MAIN OUTCOME: To study the expression of OX40 on T follicular helper (Tfh) cells and the ligand OX40L on antigen-presenting cells (APCs) in peripheral blood of patients with Type 1 diabetes mellitus (T1DM) and the role of OX40 signaling in promoting Tfh cells to assist B-cell differentiation. DESIGN: Cross-sectional study. SETTING: Endocrinology department of a university hospital. PARTICIPANTS: Twenty-five patients with T1DM and 35 with newly diagnosed T2DM from January 2021-December 2021 (39 males, 21 females; mean age: 31.0 ± 4.5, range: 19-46 years). INTERVENTIONS: None. METHODS: The peripheral blood proportion of CD4+CD25-CD127+CXCR5+PD1+ Tfh cells in patients with T1DM or T2DM and the OX40L expression in CD14+ monocytes and CD19+ B cells were analyzed by flow cytometry. The OX40 signal effect on Tfh-cell function was analyzed by co-incubating B cells with Tfh cells under different conditions. Flow cytometry detected the ratio of CD19-CD138+ plasmacytes. RESULTS: The Tfh cells ratio and intracellular IL-21 expression in peripheral blood was significantly higher in patients with T1DM than with T2DM, and the OX40 expression in peripheral Tfh cells and OX40L expression in APC were significantly higher in T1DM. After adding OX40L protein, the CD19-CD138+-plasmacytes percentage was significantly increased and higher in T1DM. Blocking of anti-OX40L monoclonal antibodies significantly reduced the plasmacytes ratio. CONCLUSIONS: The peripheral Tfh cells proportion increased and the OX40 expression in peripheral Tfh cells was upregulated in patients with T1DM versus patients with T2DM. OX40/OX40L signaling enhanced the Tfh-cell function to assist B-cell differentiation, which may contribute to the pathogenesis of T1DM.

Copper-Catalyzed Enantioconvergent Radical N-Alkylation of Diverse (Hetero)aromatic Amines.

The 3d transition metal-catalyzed enantioconvergent radical cross-coupling provides a powerful tool for chiral molecule synthesis. In the classic mechanism, the bond formation relies on the interaction between nucleophile-sequestered metal complexes and radicals, limiting the nucleophile scope to sterically uncongested ones. The coupling of sterically congested nucleophiles poses a significant challenge due to difficulties in transmetalation, restricting the reaction generality. Here, we describe a probable outer-sphere nucleophilic attack mechanism that circumvents the challenging transmetalation associated with sterically congested nucleophiles. This strategy enables a general copper-catalyzed enantioconvergent radical N-alkylation of aromatic amines with secondary/tertiary alkyl halides and exhibits catalyst-controlled stereoselectivity. It accommodates diverse aromatic amines, especially bulky secondary and primary ones to deliver value-added chiral amines (>110 examples). It is expected to inspire the coupling of more nucleophiles, particularly challenging sterically congested ones, and accelerate reaction generality.

NSUN2 promotes lung adenocarcinoma progression through stabilizing PIK3R2 mRNA in an m5C-dependent manner.

It is well known that 5-methylcytosine (m5C) is involved in variety of crucial biological processes in cancers. However, its biological roles in lung adenocarcinoma (LAUD) remain to be determined. The LUAD samples were used to assess the clinical value of NOP2/Sun RNA Methyltransferase 2 (NSUN2). Dot blot was used to determine global m5C levels. ChIP and dual-luciferase assays were performed to investigate the MYC-associated zinc finger protein (MAZ)-binding sites in NSUN2 promoter. RNA-seq was used to explore the downstream molecular mechanisms of NSUN2. Dual luciferase reporter assay, m5C-RIP-qPCR, and mRNA stability assay were conducted to explore the effect of NSUN2-depletion on target genes. Cell viability, transwell, and xenograft mouse model were designed to demonstrate the characteristic of NSUN2 in promoting LUAD progression. The m5C methyltransferase NSUN2 was highly expressed and caused elevated m5C methylation in LUAD samples. Mechanistically, MAZ positively regulated the transcription of NSUN2 and was related to poor survival of LUAD patients. Silencing NSUN2 decreased the global m5C levels, suppressed proliferation, migration and invasion, and inhibited activation of PI3K-AKT signaling in A549 and SPAC-1 cells. Phosphoinositide-3-Kinase Regulatory Subunit 2 (PIK3R2) was upregulated by NSUN2-mediated m5C methylation by enhancing its mRNA stabilization and activated the phosphorylation of the PI3K-AKT signaling. The present study explored the underlying mechanism and biological function of NSUN2-meditated m5C RNA methylation in LUAD. NSUN2 was discovered to facilitate the malignancy progression of LUAD through regulating m5C modifications to stabilize PIK3R2 activating the PI3K-AKT signaling, suggesting that NSUN2 could be a novel biomarker and promising therapeutic target for LUAD patients.

Construction of tumor organoids and their application to cancer research and therapy.

Cancer remains a severe public health burden worldwide. One of the challenges hampering effective cancer therapy is that the existing cancer models hardly recapitulate the tumor microenvironment of human patients. Over the past decade, tumor organoids have emerged as an in vitro 3D tumor model to mimic the pathophysiological characteristics of parental tumors. Various techniques have been developed to construct tumor organoids, such as matrix-based methods, hanging drop, spinner or rotating flask, nonadhesive surface, organ-on-a-chip, 3D bioprinting, and genetic engineering. This review elaborated on cell components and fabrication methods for establishing tumor organoid models. Furthermore, we discussed the application of tumor organoids to cancer modeling, basic cancer research, and anticancer therapy. Finally, we discussed current limitations and future directions in employing tumor organoids for more extensive applications.

Solvent-Resistant Adhesive Gel with Thermal Post-Tunability.

Adhesives have received extensive attention in flexible bioelectronics, wearable electronic medical devices, and biofuel cells. However, it is a challenge to achieve late regulation of performance once polymer-based gels are formed. Here, a double-network organogel composed of a hydrophilic and hydrophobic polymer network and a polyamide acid network was successfully prepared. In diverse liquid environments (including isopropyl alcohol, glycerol, epichlorohydrin, n-propanol, dichloromethane, triethanolamine, ethanol absolute, hydrogen peroxide, and ethyl acetate), the organogel adhesive demonstrated remarkable properties. It exhibits a strong tensile strength of 200 kPa, a high fracture strain reaching 560%, and an impressive adhesion strength of 38 kPa. In addition, the organogel demonstrates exceptional adhesive properties toward polytetrafluoroethylene, plastics, metals, rubber, and glass. Note that the organogel could also regulate adhesive and tough performance by thermally triggering a cyclization reaction even after the organogel has been formed. The strategy provides a new idea for designing soft materials with post-tunability.

Molecular mechanisms of the RNA polymerases in plant RNA-directed DNA methylation.

In plants, two atypical DNA-dependent RNA polymerases, RNA polymerase IV (Pol IV) and Pol V, and an RNA-DEPENDENT RNA POLYMERASE 2 (RDR2) together produce noncoding RNAs (ncRNAs) to guide the plant-specific RNA-directed DNA methylation (RdDM). Although both Pol IV and Pol V have evolved from the canonical Pol II, they have adapted to different roles in RdDM. The mechanisms of their adaptation are key to understanding plant DNA methylation and the divergent evolution of polymerases. In this review, we summarize insights that have emerged from recent structural studies of Pol IV, Pol V, and RDR2 and discuss their structural features critical for efficient ncRNA production in RdDM.

IFN-γ enhances the therapeutic efficacy of MSCs-derived exosome via miR-126-3p in diabetic wound healing by targeting SPRED1.

BACKGROUND AND AIMS: The traditional treatment of diabetic wounds is unsatisfactory. Exosomes isolated from bone marrow mesenchymal stem cells (BMSCs) promote the healing of diabetic wounds. However, whether the exosomes secreted by interferon (IFN)-γ-pretreated BMSCs have an enhanced therapeutic effect on diabetic wound healing and the relevant mechanisms remain unclear. METHODS: In this study, we isolated exosomes from the corresponding supernatants of BMSCs with (IExos) or without IFN-γ treatment (NExos). Human umbilical vein endothelial cells (HUVECs) were used to investigate the proliferation, migration, and tube formation under different treatments in vitro. Diabetic mice were induced by intraperitoneal administration of streptozotocin, and a circular full-thickness dermal defect was then made on the back of each mouse, followed by a multisite subcutaneous injection of phosphate buffered saline or exosomes. Hematoxylin-eosin (H&E) staining, Masson's trichrome staining, and histological analysis were performed to assess the speed and quality of wound healing. RESULTS: NExos treatment accelerated the healing of diabetic wounds by promoting angiogenesis in vivo and in vitro, and IExos exhibited superior therapeutic efficiency. MicroRNA (miR)-126-3p was significantly increased in IExos, and exosomal miR-126-3p promoted angiogenesis and diabetic wound healing via its transfer to HUVECs. miR-126-3p regulates SPRED1 by directly targeting the 3'-UTR. Mechanistically, IFN-γ-pretreated BMSCs secreted miR-126-3p-enriched exosomes, which enhanced the function of HUVECs and promoted angiogenesis via the SPRED1/Ras/Erk pathway. CONCLUSION: Exosomal miR-126-3p secreted from IFN-γ-pretreated BMSCs exhibited higher therapeutic efficacy than NExos in diabetic wound healing by promoting angiogenesis via the SPRED1/Ras/Erk axis.

[Screening and promoting effect of grow-promoting fungi in rhizosphere of Angelica dahurica var. formosana].

Excessive application of chemical fertilizer has caused many problems in Angelica dahurica var. formosana planting, such as yield decline and quality degradation. In order to promote the green cultivation mode of A. dahurica var. formosana and explore rhizosphere fungus resources, the rhizosphere fungi with nitrogen fixation, phosphorus solubilization, potassium solubilization, iron-producing carrier, and IAA-producing properties were isolated and screened in the rhizosphere of A. dahurica var. formosana from the genuine and non-genuine areas, respectively. The strains were identified comprehensively in light of the morphological characteristics and ITS rDNA sequences, and the growth-promoting effect of the screened strains was verified by pot experiment. The results showed that 37 strains of growth-promoting fungi were isolated and screened from the rhizosphere of A. dahurica var. formosana, mostly belonging to Fusarium. The cultured rhizosphere growth-promoting fungi of A. dahurica var. formosana were more abundant and diverse in the genuine producing areas than in the non-genuine producing areas. Among all strains, Aspergillus niger ZJ-17 had the strongest growth promotion potential. Under the condition of no fertilization outdoors, ZJ-17 inoculation significantly promoted the growth, yield, and accumulation of effective components of A. dahurica var. formosana planted in the soil of genuine and non-genuine producing areas, with yield increases of 73.59% and 37.84%, respectively. To a certain extent, it alleviated the restriction without additional fertilization on the growth of A. dahurica var. formosana. Therefore, A. niger ZJ-17 has great application prospects in increasing yield and quality of A. dahurica var. formosana and reducing fertilizer application and can be actually applied in promoting the growth of A. dahurica var. formosana and producing biofertilizer.

Fabrication of electrospun cellulose/chitosan/ball-milled bone char membranes for efficient and selective sorption of Pb(II) from aqueous solutions.

Separation materials have received increasing attention given their broad applications in the management of environmental pollution. It is desired to balance the contradiction between high separation efficiency and selectivity of separation materials. The integration of ball-milled bone chars with electrospun membranes might achieve this balance. In this study, electrospun cellulose/chitosan/ball-milled bone char (CL/CS/MB) membranes were by well-dispersing ball-milled bone chars with nanoscale size (98.9-167.5 nm) and developed porosity (40.2-373.1 m2/g) in the electrospinning solvent. The synergistic integration of distributed MBs (5.4-31.5 wt.% of loading hydroxyapatite on the membrane matrix) allowed the efficient sorption of Pb(II) with fast kinetics (20.0 min), excellent capacity (219.9 mg/g at pH 5.0, T 298 K), and favorable selectivity coefficients (2.76-6.79). The formation of minerals was dominant for the selective sorption of Pb(II) by combining the spectral analysis and quantitative determination. The surface complexation with O-/reductive N-species, the cation exchange with inorganic Ca2+, the electrostatic attraction with deprotonated O-, and the cation-π coordination with the aromatic carbon via the π-electrons should be not ignored for the capture of Pb(II). This work demonstrated the feasibility of electrospun CL/CS/MB membranes as a promising candidate for the remediation of aquatic pollutants.

Comprehensive Evaluation of Lipid Nanoparticles and Polyplex Nanomicelles for Muscle-Targeted mRNA Delivery.

The growing significance of messenger RNA (mRNA) therapeutics in diverse medical applications, such as cancer, infectious diseases, and genetic disorders, highlighted the need for efficient and safe delivery systems. Lipid nanoparticles (LNPs) have shown great promise for mRNA delivery, but challenges such as toxicity and immunogenicity still remain to be addressed. In this study, we aimed to compare the performance of polyplex nanomicelles, our original cationic polymer-based carrier, and LNPs in various aspects, including delivery efficiency, organ toxicity, muscle damage, immune reaction, and pain. Our results showed that nanomicelles (PEG-PAsp(DET)) and LNPs (SM-102) exhibited distinct characteristics, with the former demonstrating relatively sustained protein production and reduced inflammation, making them suitable for therapeutic purposes. On the other hand, LNPs displayed desirable properties for vaccines, such as rapid mRNA expression and potent immune response. Taken together, these results suggest the different potentials of nanomicelles and LNPs, supporting further optimization of mRNA delivery systems tailored for specific purposes.

Magnetic field modulation effect of photoelectric properties in dye-sensitized solar cells with La0.67(Ca,Ba)0.33MnO3 as counter electrodes.

BACKGROUND: In recent years, many semiconductor materials with unique band structures have been used as Pt counter electrode (CE) substitutes for dye-sensitized solar cells (DSSCs), which makes the photoelectric properties of DSSCs possible to be modulated by electric field, magnetic field, and light field. In this work, La0.67(Ca Ba)0.33MnO3 (LCBMO) thin film is employed to act as CE in DSSCs. METHOD: The experimental results indicate that short-circuit current density and photoelectric conversion efficiency present better stability when applying an external magnetic field to the DSSCs. Furthermore, both the exchange current density (J0) and limit diffusion current density (Jlim) are largely enhanced by an external magnetic field. J0 increases from -0.51 mA•cm-2 to -0.65 mA•cm-2, and Jlim increases from 0.2 mA•cm-2 to 0.3 mA•cm-2 when applying a magnetic field of 0.25 T. RESULT: The fitting results of the impedance test verify that the magnetic field reduces the value of Rct. CONCLUSION: Both magnetic-field enhancing catalytic activity and CMR effect jointly promote the increase of photocurrent and finally improve the photovoltaic effect in DSSCs.

SCD1 inhibits HBV replication by regulating autophagy under high lipid conditions.

Chronic hepatitis B virus (HBV) infection remains a significant public health concern worldwide. Several metabolic processes regulate HBV DNA replication, including autophagy and lipid metabolism. In this study, we clarified the effect of lipids on HBV replication and elucidated possible mechanisms. We discovered that lipid metabolic gene expression levels were negatively correlated with the HBV DNA in plasma. Our data showed that fatty acid stimulation significantly reduced HBV DNA, hepatitis B surface antigen (HBsAg), and hepatitis B e antigen (HBeAg) levels in HepG2.2.15 cells, which are human hepatoma cell cultures transfected with HBV DNA. The Stearoyl coenzyme A desaturase 1 (SCD1)-autophagy pathway has also been implicated in inhibiting HBV replication by fatty acids stimulation. SCD1 knockdown deregulates the inhibitory effect of fatty acids on HBV by enhancing autophagy. When 3 methyladenine (3MA) was added, the inhibitory effects of specific autophagy inhibitors eliminated the positive effects of SCD1 knockdown on HBV replication. Our results indicate that SCD1 participates in the regulation of inhibition of HBV replication by fatty acids stimulation through regulating autophagy.

Copper-Catalyzed Enantioconvergent Radical C(sp3)-N Cross-Coupling of Activated Racemic Alkyl Halides with (Hetero)aromatic Amines under Ambient Conditions.

The enantioconvergent C(sp3)-N cross-coupling of racemic alkyl halides with (hetero)aromatic amines represents an ideal means to afford enantioenriched N-alkyl (hetero)aromatic amines yet has remained unexplored due to the catalyst poisoning specifically for strong-coordinating heteroaromatic amines. Here, we demonstrate a copper-catalyzed enantioconvergent radical C(sp3)-N cross-coupling of activated racemic alkyl halides with (hetero)aromatic amines under ambient conditions. The key to success is the judicious selection of appropriate multidentate anionic ligands through readily fine-tuning both electronic and steric properties for the formation of a stable and rigid chelating Cu complex. Thus, this kind of ligand could not only enhance the reducing capability of a copper catalyst to provide an enantioconvergent radical pathway but also avoid the coordination with other coordinating heteroatoms, thereby overcoming catalyst poisoning and/or chiral ligand displacement. This protocol covers a wide range of coupling partners (89 examples for activated racemic secondary/tertiary alkyl bromides/chlorides and (hetero)aromatic amines) with high functional group compatibility. When allied with follow-up transformations, it provides a highly flexible platform to access synthetically useful enantioenriched amine building blocks.

3D smooth path planning of AUV based on improved ant colony optimization considering heading switching pressure.

A smooth and secure spatial path planning algorithm that integrates the improved ant colony optimization with the corrective connected spatial search strategy is proposed, aiming at heavy heading switching pressure of autonomous underwater vehicles sailing in complex marine environment. On the one hand, to overcome the low-dimensional search domain and inaccurate spatial communication information in traditional spatial path planning, the spatial connectivity adjacency domain search strategy is designed based on grid environment model. On the other hand, to alleviate heading switching pressure due to large path steering angles and redundant path turning points, the heuristic functions and pheromone update criterion based on ant colony optimization are introduced to improve the solution quality of smooth paths. The simulation results show that the space search strategy can improve the success probability of safe path planning without reducing the scope of explorable free space. Additionally, the simulations demonstrate that the improved ant colony optimization using the spatial search strategy can guarantee the shortest path with lowest tortuous degree and fewest turning times in the same grid environment.

Cigarette smoking, by accelerating the cell cycle, promotes the progression of non-small cell lung cancer through an HIF-1α-METTL3-m6A/CDK2AP2 axis.

Cigarette smoking killed about 8 million people every year and promoted non-small cell lung cancer (NSCLC). We investigated the molecular mechanism of smoking-promoted NSCLC progression. Relative to non-smokers, NSCLC patients who were smokers had a higher tumor malignancy. For NSCLC cells, cigarette smoke extract (CSE) increased levels of HIF-1α, METTL3, Cyclin E1, and CDK2 and promoted the G1/S transition, which promoted cell proliferation. Down-regulation HIF-1α or METTL3 reversed these effects. meRIP-seq and RNA-seq revealed the m6A modification in Cyclin Dependent Kinase 2 Associated Protein 2 (CDK2AP2) mRNA as the key downstream target. Further, for NSCLC cells exposed to CSE, HIF-1α activated METTL3 transcription. Xenografts in nude mice demonstrated that HIF-1α via METTL3 participated in tumor growth. In NSCLC tissues of smokers, protein levels of HIF-1α and METTL3 were higher, and levels of CDK2AP2 were lower. In conclusion, HIF-1α via METTL3 regulation of the m6A modification of CDK2AP2 mRNA drives smoking-induced progression of NSCLC through promoting cell proliferation. This is a previously unknown molecular mechanism for smoking-induced NSCLC progression. The results have potential value for treatment of NSCLC, especially for patients who smoke.

Smoking-Induced M2-TAMs, via circEML4 in EVs, Promote the Progression of NSCLC through ALKBH5-Regulated m6A Modification of SOCS2 in NSCLC Cells.

Lung cancer is a commonly diagnosed disease worldwide, with non-small cell lung cancers (NSCLCs) accounting for ≈ 85% of cases. Cigarette smoke is an environmental exposure promoting progression of NSCLC, but its role is poorly understood. This study reports that smoking-induced accumulation of M2-type tumor-associated macrophages (M2-TAMs) surrounding NSCLC tissues promotes malignancy. Specifically, extracellular vesicles (EVs) from cigarette smoke extract (CSE)-induced M2 macrophages promoted malignancy of NSCLC cells in vitro and in vivo. circEML4 in EVs from CSE-induced M2 macrophages is transported to NSCLC cells, where it reduced the distribution of ALKBH5 in the nucleus by interacting with Human AlkB homolog H5 (ALKBH5), resulting in elevated N6-methyladenosine (m6A) modifications. m6A-seq and RNA-seq revealed suppressor of cytokine signaling 2 (SOCS2)-mediated activation of the Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway by regulating m6A modification of SOCS2 via ALKBH5. Down-regulation of circEML4 in EVs from CSE-induced M2 macrophages reversed EVs-enhanced tumorigenicity and metastasis in NSCLC cells. Furthermore, this study found that smoking patients showed an increase in circEML4-positive M2-TAMs. These results indicate that smoking-induced M2-TAMs via circEML4 in EVs promote the NSCLC progression through ALKBH5-regulated m6A modification of SOCS2. This study also reveals that circEML4 in EVs from TAMs acts as a diagnostic biomarker for NSCLC, especially for patients with smoking history.

An Underutilized Food "Miwu": Diet History, Nutritional Evaluations, and Countermeasures for Industrial Development.

About 10 major crops basically feed the world. In fact, there are still a large number of plants that have not been fully explored and utilized because they have been ignored by the market and research. The expansion of food sources in various countries plays an important role in maintaining food security and nutrition security in the world. Miwu is the aerial part of the medicinal plant Rhizoma Chuanxiong belonging to a traditional local characteristic food raw material. Its edible value is still little known. Through textual research, component determination, literature survey, field research, and SWOT analysis, this paper has a comprehensive understanding of Miwu's diet history, chemical components, safety risks, and industrial development status. It is found that Miwu has been eaten for 800 years, is rich in nutrients and active ingredients, and has no acute toxicity. In addition, the current industrial development of Miwu has significant advantages and many challenges. To sum up, Miwu is a potentially underutilized food raw material. This paper also provides countermeasures for the industrialized development of Miwu, which will provide a milestone reference for the future utilization and development of Miwu.

Antibacterial activity and mechanism of sanguinarine against Staphylococcus aureus by interfering with the permeability of the cell wall and membrane and inducing bacterial ROS production.

Staphylococcus aureus (SA) is representative of gram-positive bacteria. Sanguinarine chloride hydrate (SGCH) is the hydrochloride form of sanguinarine (SG), one of the main extracts of Macleaya cordata (M. cordata). There are few reports on its antibacterial mechanism against SA. Therefore, in this study, we investigated the in vitro antibacterial activity and mechanism of SGCH against SA. The inhibitory zone, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) were measured, and the bactericidal activity curve was plotted. In addition, the micromorphology, alkaline phosphatase (AKP) activity, Na+K+, Ca2+Mg2+-adenosine triphosphate (ATP) activity, intracellular reactive oxygen species (ROS), and fluorescein diacetate (FDA) were observed and detected. The results showed that the inhibitory zone of SGCH against SA was judged as medium-sensitive; the MIC and MBC were 128 and 256 µg/mL, respectively; in the bactericidal activity curve, SGCH with 8 × MIC could completely kill SA within 24 h. SGCH was able to interfere with the integrity and permeability of the SA cell wall and membrane, as confirmed by the scanning electron microscopy (SEM) images, the increase in extracellular AKP and Na+ K+, Ca2+ Mg2+-ATP activities as well as the fluorescein diacetate (FDA) staining experiment results. Moreover, a high concentration of SGCH could induce SA to produce large amounts of ROS. In summary, these findings revealed that SGCH has a preferable antibacterial effect on SA, providing an experimental and theoretical basis for using SG as an antibiotic substitute in animal husbandry and for the clinical control and treatment of diseases caused by SA.

Widespread presence of chlorinated paraffins in consumer products.

Short-chain chlorinated paraffins (SCCPs) were listed for elimination under the Stockholm Convention in 2017 due to their persistence and toxicity. Although Canada and other Stockholm signatories have prohibited the manufacture, usage and import of SCCPs since 2013, they can still be detected at high concentrations in indoor dust. To identify the sources of the SCCPs in the Canadian indoor environment, short-, medium- and long-chain chlorinated paraffins (SCCPs, MCCPs, LCCPs, respectively) were measured using a sensitive LC-ESI-orbitrap method. SCCPs were detected in 84 of the 96 products purchased in Canada after 2013 (87.5%) including electronic devices, clothing, plastics (toys), and paintings. Concentrations of SCCPs were up to 0.93% (9.34 mg g-1). SCCPs were also detected in newly purchased toys at 0.005-2.02 mg g-1, indicating the potential for children's exposure. Profiles of chlorinated paraffins differed among categories of products. For example, C13-SCCPs were most common in toys, while electronic devices like headphones showed comparable concentrations of SCCPs and MCCPs. Additionally, four new carboxylate derivatives of CPs were detected in an electronic device sample. These are the first data to show the ubiquitous occurrences of SCCPs in a wide range of products currently marketed in Canada, suggesting continuing indoor exposure to SCCPs despite their prohibition.