IL-21, not IL-17A, exacerbates murine primary biliary cholangitis.

Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease caused by intrahepatic bile duct injuries, resulting in fibrosis, cirrhosis, and eventually liver failure. T helper (Th) 17 cells are proposed to involve in the pathogenesis of PBC. However, how and which Th17 cell-derived cytokines affect PBC remains unclear. In this study, we investigated the effects of Th17 effector cytokines, including interleukin (IL)-17A, IL-17F, and IL-21 in PBC using a xenobiotic-induced mouse model of autoimmune cholangitis (inducible chemical xenobiotic models of PBC) treated with cytokine-expressing adeno-associated virus. Our results showed that administration of IL-17A, the well-known main cytokine produced by Th17 cells, did not augment liver inflammation or fibrosis. In contrast, we noted IL-17A-treated mice had lower hepatic Th1 cell numbers and higher hepatic CD11b+Ly6G+ polymorphonuclear myeloid-derived suppressor cell numbers. IL-17F did not alter liver inflammation or fibrosis. However, the administration of IL-21 exacerbated liver inflammatory responses and portal cell infiltration. IL-21 markedly increased the numbers of activated CD8+ T cells and liver tissue-resident memory CD8+ T cells. Moreover, IL-21 aggravates liver fibrosis in mice with autoimmune cholangitis. These results emphasized that not IL-17A but IL-21 in Th17 cell-derived cytokines affected the pathogenesis of PBC. IL-21 enhanced liver inflammation and progression to fibrosis by enhancing the numbers and effector activities of CD8+ T cells. Delineation of the effects of different Th17 effector cytokines in PBC offers clues for developing new therapeutic approaches.

Regulatory T cells in inflamed liver are dysfunctional in murine primary biliary cholangitis.

Primary biliary cholangitis (PBC) is a chronic autoimmune disease characterized by immune-mediated destruction of intrahepatic small bile ducts. CD8 T cells play a critical role in biliary destruction. However, regulatory T cells (Tregs) have also been identified in the portal tracts of PBC patients. This study tested the hypothesis that hepatic Tregs in PBC were dysfunctional in suppressing immune responses in disease by using our human PBC-like autoimmune cholangitis (AIC) mouse model induced by 2-octynoic acid-conjugated ovalbumin (2-OA-OVA). Our results showed that female and male mice immunized with 2-OA-OVA developed AIC; however, female AIC mice had more severe liver inflammation and fibrosis than male AIC mice. Levels of functional effector CD8 T cells and their chemoattractants, CXCL9 and CXCL10, in the liver were markedly elevated in female AIC mice than in male AIC mice. These results reinforce that CD8 T cells are the primary effector cells in PBC. The number of hepatic Tregs in AIC mice was also higher than in saline-treated mice, but there was no difference between male and female AIC mice. The suppressive function of AIC Tregs was evident despite a discrepancy in the changes in their co-inhibitory receptors and inhibitory cytokines. However, the expansion of hepatic Tregs by low-dose IL-2 treatment did not reduce immune responses to AIC, which may be due to the dysfunction of Tregs in inhibiting T cells. In conclusion, the function of Tregs in the inflamed liver of PBC was insufficient, and low-dose IL-2 treatment could not restore their function to suppress pathological immune responses. Transferring normal Tregs or directly targeting effector CD8 T cells may be beneficial for treating PBC.

High Diversity of Fusarium Species in Onychomycosis: Clinical Presentations, Molecular Identification, and Antifungal Susceptibility.

Fusarium are uncommon but important pathogenic organisms; they cause non-dermatophyte mould (NDM) onychomycosis. Patients typically respond poorly to treatment owing to Fusarium's native resistance to multiple antifungal drugs. However, epidemiological data for Fusarium onychomycosis are lacking in Taiwan. We retrospectively reviewed the data of 84 patients with positive Fusarium nail sample cultures at Chang Gung Memorial Hospital, Linkou Branch between 2014 and 2020. We aimed to investigate the clinical presentations, microscopic and pathological characteristics, antifungal susceptibility, and species diversity of Fusarium in patients with Fusarium onychomycosis. We enrolled 29 patients using the six-parameter criteria for NDM onychomycosis to determine the clinical significance of Fusarium in these patients. All isolates were subjected to species identification by sequences and molecular phylogeny. A total of 47 Fusarium strains belonging to 13 species in four different Fusarium species complexes (with Fusarium keratoplasticum predominating) were isolated from 29 patients. Six types of histopathology findings were specific to Fusarium onychomycosis, which may be useful for differentiating dermatophytes from NDMs. The results of drug susceptibility testing showed high variation among species complexes, and efinaconazole, lanoconazole, and luliconazole showed excellent in vitro activity for the most part. This study's primary limitation was its single-centre retrospective design. Our study showed a high diversity of Fusarium species in diseased nails. Fusarium onychomycosis has clinical and pathological features distinct from those of dermatophyte onychomycosis. Thus, careful diagnosis and proper pathogen identification are essential in the management of NDM onychomycosis caused by Fusarium sp.

Apoptotic biliary epithelial cells and gut dysbiosis in the induction of murine primary biliary cholangitis.

Primary biliary cholangitis (PBC) is a female-predominant liver autoimmune disease characterized by the specific immune-mediated destruction of the intrahepatic small bile duct. Although apoptosis of biliary epithelial cells (BECs) and alterations in gut microbiota are observed in patients with PBC, it is still unclear whether these events happen in the early stage and cause the breakdown of tolerance in PBC. In this study, we examined the early events in the loss of tolerance in our well-defined 2-OA-OVA-induced murine autoimmune cholangitis (AIC) model. We report herein that apoptosis of BECs was notable in the early stage of murine AIC. An altered gut microbiota, in particular, an increased percentage of gram-positive Firmicutes in AIC mice was also observed. BECs in AIC mice expressed adhesion molecule ICAM-1, cytokines/chemokines TNF-α, CCL2, CXCL9, CXCL10, and toll-like receptor (TLR) 2. Moreover, BECs treated with TLR2 ligand had elevated apoptosis and CXCL10 production. These data collectively suggest a new mechanism of tolerance breakdown in AIC. Altered gut microbiota induces apoptosis of BECs through TLR2 signaling. BECs secrete chemokines to recruit CD8 T cells to damage BECs further.

Evaluating the release and metabolism of ricinine from castor cake fertilizer in soils using a LC-QTOF/MS coupled with SIRIUS workflow.

Castor cake is a major by-product generated after castor oil extraction and has been widely used as an organic fertilizer. Once applied to soil, a toxic alkaloid ricinine in castor cake may be released into soils and subsequently taken up by crops, which poses a potential threat to food safety and human health. However, the environmental fate of castor cake derived ricinine in agroecosystems remains unclear. In this study, the release and metabolism of ricinine in soils were conducted using soil pot experiments with different castor cake application rates. The analytical methodology of ricinine quantification in soil pore water was first established using solid phase extraction (SPE) coupled with liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF/MS). A non-target screening workflow associated with LC-QTOF/MS and SIRIUS platform was further developed to identify ricinine metabolites in soil pore water. After castor cake application, the ricinine concentrations in soil pore water significantly increased to 297-7990 µg L-1 at 1 day and then gradually decreased to 62.1-3460 µg L-1 at 7 days and 1.70-279 µg L-1 at 14 days for the selected two tested soils with castor cake application rates of 2, 10, and 20 g castor cake/kg soil. In addition, two ricinine metabolites R-194 and R-180 were tentatively identified and one ricinine metabolite N-demethyl-ricinin was confirmed through authentic reference standard for the first time by the developed non-target screening workflow. This study highlights the release and metabolism of toxic alkaloid ricinine in soils once applied castor cake as an organic fertilizer. Ricinine could be released into soil pore water in a short-term after castor cake application and then undergo demethylation, hydroxylation, and hydroxylation followed by methylation metabolisms over time in agroecosystems.

HLJ1 amplifies endotoxin-induced sepsis severity by promoting IL-12 heterodimerization in macrophages.

Heat shock protein (HSP) 40 has emerged as a key factor in both innate and adaptive immunity, whereas the role of HLJ1, a molecular chaperone in HSP40 family, in modulating endotoxin-induced sepsis severity is still unclear. During lipopolysaccharide (LPS)-induced endotoxic shock, HLJ1 knockout mice shows reduced organ injury and IFN-γ (interferon-γ)-dependent mortality. Using single-cell RNA sequencing, we characterize mouse liver nonparenchymal cell populations under LPS stimulation, and show that HLJ1 deletion affected IFN-γ-related gene signatures in distinct immune cell clusters. In CLP models, HLJ1 deletion reduces IFN-γ expression and sepsis mortality rate when mice are treated with antibiotics. HLJ1 deficiency also leads to reduced serum levels of IL-12 in LPS-treated mice, contributing to dampened production of IFN-γ in natural killer cells but not CD4+ or CD8+ T cells, and subsequently to improved survival rate. Adoptive transfer of HLJ1-deleted macrophages into LPS-treated mice results in reduced IL-12 and IFN-γ levels and protects the mice from IFN-γ-dependent mortality. In the context of molecular mechanisms, HLJ1 is an LPS-inducible protein in macrophages and converts misfolded IL-12p35 homodimers to monomers, which maintains bioactive IL-12p70 heterodimerization and secretion. This study suggests HLJ1 causes IFN-γ-dependent septic lethality by promoting IL-12 heterodimerization, and targeting HLJ1 has therapeutic potential in inflammatory diseases involving activated IL-12/IFN-γ axis.

Evolution of Cryoglobulinemia in Direct-Acting Antiviral-Treated Asian Hepatitis C Patients With Sustained Virological Responses: A 4-Year Prospective Cohort Study.

Background: How cryoglobulinemia evolves after sustained virological response (SVR) following direct-acting antiviral (DAA) treatment in Asian hepatitis C virus (HCV)-infected patients remains elusive. Methods: A prospective cohort study was conducted in 422 Taiwanese patients (358 completed DAA therapy and 353 experienced SVRs). Serum cryoglobulins were surveyed at baseline and every 3-6 months posttherapy. Results: Of 422, 227 (53.8%) had cryoglobulinemia, 8 (1.89%) had cryoglobulinemic vasculitis. Of 227, 54 (23.8%), 57 (25.1%) and 116 (51.1%) had 1, 2 and 3 cryoglobulins, respectively; those with 3 cryoglobulins had the highest alanine aminotransferase, immunoglobulin G (IgG) and fibrosis-4 index. During a 4-year follow-up, among SVR patients, cryoglobulinemia rates decreased from 56.4% to 15.4%, single cryoglobulin rates increased (21.6% to 63.9%) and 3 cryoglobulin rates decreased (55.7% to 11.1%). Compared with baseline values, among SVR patients with baseline cryoglobulinemia, complement component 4 levels increased, and IgG and IgM levels decreased until 48 weeks posttherapy for those without posttherapy cryoglobulinemia. All 8 cryoglobulinemic vasculitis patients exhibited SVRs; 5 (62.5%) achieved complete clinical response 12 weeks posttherapy, of whom, 2 (40%) experienced clinical relapse 24~48 weeks posttherapy. Baseline IgM levels were associated with posttherapy cryoglobulinemia in SVR patients (cut-off values at 12, 24, 48 weeks and 4 years posttherapy: 130, 105, 118 and 168 mg/dL, respectively). Conclusions: Among DAA-treated SVR patients, in 4 years, cryoglobulinemia rates decreased from 56.4% to 15.4%, multiple cryoglobulin rates decreased, cryoglobulinemia signals reversed, 62.5% of cryoglobulinemic vasculitis patients achieved complete clinical response (40% had relapse), and baseline IgM levels indicated posttherapy cryoglobulinemia.

Area-population control of fungus-growing termite, Odontotermes formosanus, using hexaflumuron durable baits.

BACKGROUND: Fungus-growing termites (Termitidae: Macrotermitinae) are common forest and agriculture pests. To evaluate the efficacy of termite baiting in suppressing field population of fungus-growing termites, a durable termite bait with hexaflumuron was evenly installed in a one-hectare forest area dominated by a fungus-growing termite, Odontotermes formosanus (Shiraki). Monthly monitoring of termite foraging activity on baits and wood stakes was conducted for 4 years to quantify efficacy of baits. To examine whether the hexaflumuron led to colony death, pesticides in fungus gardens of active and deceased nests were quantified using a LC-QTOF/MS. RESULTS: After baiting, 50% and 90% of baits were fed upon 10 and 24 months, respectively. After 2 years of baiting, the monthly number of wood stakes occupied by termites was reduced from 34.7 ± 1.8 to 17.6 ± 2.5 (-49.1%), and the number of wood stakes consumed was reduced from 17.7 ± 0.8 to 13.3 ± 1.2 (-25.7%). Hexaflumuron was detected in deceased colonies, including five of six fungus gardens and the fungal tissue of Xyleria grown on fungus gardens, with a concentration of 0.31-20.11 mg kg-1 dry weight. CONCLUSION: This study demonstrated that durable hexaflumuron baits consumed by fungus-growing termites were further incorporated into fungus gardens, resulted in colony elimination and negative area-population effects, supporting that durable hexaflumuron baits are effective in suppressing field populations of fungus-growing termites. © 2021 Society of Chemical Industry.

Dynamics of cellular immune responses in recipients of renal allografts positive for hepatitis B surface antigen.

BACKGROUND/PURPOSE: Hepatitis B surface antigen (HBsAg)-positive renal transplantation recipients must take lifelong immunosuppressants and nucleotide analogues (NAs). We investigated the cellular immune responses of HBsAg-positive renal transplantation recipients taking immunosuppressants and NAs. METHODS: Blood samples were collected from HBsAg-positive individuals with end-stage renal disease on the transplant waiting list (Group 1) and renal transplantation recipients taking immunosuppressants and NAs (Group 2) or immunosuppressants without NAs (Group 3). Hepatitis B virus (HBV)-specific pentamers were used to quantify circulating HBV-specific CD8+ T cells. RESULTS: Groups 2 and 3 had higher cellular immune responses, as indicated by significantly lower regulatory T (Treg)/CD8+ T cell ratios than Group 1. With undetectable viral loads under both immunosuppressant and NAs, the CD8+ T cell and HBV-specific CD8+ T cell frequencies were similar in Group 2 and Group 1. Patients in Group 3 did not use NAs and had an elevated viral load and higher HBV-specific CD8+ T cell and IFN-γ-producing HBV-specific CD8+ T cell frequencies, but lower a frequency of programmed death-1 (PD-1)+ HBV-specific CD8+ T cells than the other groups. Increased viral replication in Group 3 resulted in significantly higher CD8+ T cell and IFN-γ-producing CD8+ T cell frequencies than Group 1. CONCLUSION: Immunosuppressant therapy increases viral replication in HBsAg-positive renal transplant recipients due to disabling or dysregulation of virus-specific CD8+ T cells. The higher cellular immune responses due to lower Treg/CD8+ T cell ratios in HBsAg-positive renal transplant recipients may be one of the reasons to induce liver pathology because of uncontrolled viral replication.

Interleukin-30 Suppresses Not Only CD4+ T Cells but Also Regulatory T Cells in Murine Primary Biliary Cholangitis.

Primary biliary cholangitis (PBC) is a chronic liver autoimmune disease with augmented T helper (Th) 1 and corresponding cytokine IFN-γ immune responses. Using 2-octynoic acid (2-OA) coupled to OVA (2-OA-OVA)-induced mouse models of autoimmune cholangitis (inducible chemical xenobiotic models of PBC), our previous study demonstrated that overexpression of IFN-γ in the model mice enhanced liver inflammation upon disease initiation, but subsequently led to the suppression of chronic inflammation with an increase in interleukin-30 (IL-30) levels. In this study, we investigated whether IL-30 had an immunosuppressive function and whether it could be part of an immune therapeutic regimen for PBC, by treating model mice with murine IL-30-expressing recombinant adeno-associated virus (AAV-mIL-30). We first defined the effects of AAV-mIL-30 in vivo by administering it to a well-known concanavalin A (ConA)-induced hepatitis model of mice and found that AAV-mIL-30 reduced the numbers of activated CD25+CD4+ T cells and the levels of serum IFN-γ and IL-12. In autoimmune cholangitis, decreased numbers of activated CD4+ T cells and Foxp3+ regulatory T cells were noted in the mice treated with AAV-mIL-30 at 3 weeks after the 2-OA-OVA immunization. Treatment with IL-30 did not change the features of autoimmune cholangitis including autoantibodies, cell infiltration, and collagen deposition in the liver at 11 weeks of examination. However, increased levels of cytokines and chemokines were observed. These results suggest that IL-30 suppresses not only CD4+ T cells but also regulatory T cells. Additionally, the administration of IL-30 did not suppress liver inflammation in the murine model of PBC.

Effective carbon dioxide sorption by using phyllosilicate anchored poly(quaternary-ammoniumhydroxidemethyl styrene) nanocomposites.

Polymers are highly promising materials for capturing carbon dioxide (CO2), a greenhouse gas. Hence in this work, we prepared phyllosilicate supported mesoporous polymer via reversible addition-fragmentation chain transfer (RAFT) polymerisation, which is the one among the controlled radical polymerisation. The mesoporous material anchored on dodecanethiol trithiocarbonate acts as a chain transfer agent (CTA) for the polymerisation of chloromethyl styrene and further conversion to quaternary ammonium compound which is effective to trap CO2 using tertiary amine. The synthesised porous phyllosilicate/polymer nanocomposites have been characterised by using various analytical tools. The CO2 sorption experiments were carried out by passing CO2 onto the synthesised porous phyllosilicate/polymer nanocomposites. The sorption kinetics was monitored by X-Ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR) spectra in the presence of carbonate were obtained by reaction of quaternary ammonium hydroxide and CO2. The phyllosilicate anchored macromolecular CTA (macro-CTA) and the surface-initiated polymer nanocomposites encompassed apparent surface areas of 94.5 and 26.8 m2 g-1, respectively. In addition, the total pore volumes calculated for the macro-CTA and polymer were found to be 0.27 and 0.095 cm3g-1, while the average pore sizes were 14.24 and 11.46 nm, respectively. The CO2 sorption capacity of the phyllosilicate/polymer nanocomposites, monitored at different temperatures, is the fastest for 25°C but slower for the sample treated at 50°C which may due to the dipole and quadrupole interaction.

Janus Kinase 3 Deficiency Promotes Vascular Reendothelialization-Brief Report.

[Figure: see text].

Afatinib Exerts Immunomodulatory Effects by Targeting the Pyrimidine Biosynthesis Enzyme CAD.

Current clinical trials of combined EGFR-tyrosine kinase inhibitors (TKI) and immune checkpoint blockade (ICB) therapies show no additional effect. This raises questions regarding whether EGFR-TKIs attenuate ICB-enhanced CD8+ T lymphocyte function. Here we show that the EGFR-TKI afatinib suppresses CD8+ T lymphocyte proliferation, and we identify CAD, a key enzyme of de novo pyrimidine biosynthesis, to be a novel afatinib target. Afatinib reduced tumor-infiltrating lymphocyte numbers in Lewis lung carcinoma (LLC)-bearing mice. Early afatinib treatment inhibited CD8+ T lymphocyte proliferation in patients with non-small cell lung cancer, but their proliferation unexpectedly rebounded following long-term treatment. This suggests a transient immunomodulatory effect of afatinib on CD8+ T lymphocytes. Sequential treatment of afatinib with anti-PD1 immunotherapy substantially enhanced therapeutic efficacy in MC38 and LLC-bearing mice, while simultaneous combination therapy showed only marginal improvement over each single treatment. These results suggest that afatinib can suppress CD8+ T lymphocyte proliferation by targeting CAD, proposing a timing window for combined therapy that may prevent the dampening of ICB efficacy by EGFR-TKIs. SIGNIFICANCE: This study elucidates a mechanism of afatinib-mediated immunosuppression and provides new insights into treatment timing for combined targeted therapy and immunotherapy. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/81/12/3270/F1.large.jpg.

Uptake of cephalexin by lettuce, celery, and radish from water.

The introduction of pharmaceuticals into agricultural lands from the application of biosolids and animal manure, and irrigation with treated wastewater has led to concern for animal and human health after the ingestion of pharmaceutical-tainted agricultural products. In this study, the uptake and accumulation of cephalexin, a commonly prescribed antibiotic, was compared in three common vegetables (lettuce, celery, and radish) grown in nutrient solution for 144 h. During the uptake experiments, cephalexin concentration in the nutrient solution decreased in the order of radish > celery > lettuce, while the accumulation of cephalexin in vegetable roots followed the rank of lettuce > celery > radish. The accumulation of cephalexin was below the limit of detection in radish roots. No accumulation of cephalexin was observed in the shoots of all three vegetables. The behaviors of cephalexin in vivo were further elucidated using in vitro measurements of cephalexin sorption by vegetable roots and transformation in plant enzyme extracts. The affinity of cephalexin to lettuce > celery > radish roots, and the respective sorption coefficients of 687, 303, and 161 mL g-1, coupled to the transformation of cephalexin in root enzyme extracts with estimated reaction rate constants of 0.020, 0.027 and 0.024 hr-1 for lettuce, celery and radish, could help elucidate the accumulation observed in the in vivo experiments. Overall, sorption by plant roots (affinity) and reaction with plant enzymes could collectively influence the uptake and accumulation of cephalexin in vegetables.

Lung ventilation distribution in patients after traditional full sternotomy and minimally invasive thoracotomy: An observational study.

BACKGROUND: The aim of the study was to examine the post-operative ventilation distribution changes in cardiac surgical patients after traditional full sternotomy (FS) or minimally invasive thoracotomy (MIT). METHODS: A total of 40 patients scheduled for FS with two-lung ventilation or MIT with one-lung ventilation were included. Ventilation distribution was measured with electrical impedance tomography (EIT) at T1, before surgery; T2, after surgery in ICU before weaning; T3, 24 hours after extubation. EIT-based parameters were calculated to assess the ventilation distribution, including the left-to-right lung ratio, ventral-to-dorsal ratio, and the global inhomogeneity index. RESULTS: The global inhomogeneity index increased at T2 and T3 compared to T1 in all patients but only statistically significant in patients with MIT (FS, P = .06; MIT, P < .01). Notable decrease in the dorsal regions (FS) or in the non-ventilated side (MIT) was observed at T2. Ventilation distribution was partially improved at T3 but huge variations of recovery progresses were found in all patients regardless of the surgery types. Subgroup analysis indicated that operation duration was significantly lower in the MIT group (240 ± 40 in FS vs 205 ± 90 minutes in MIT, median ± interquartile range, P < .05) but the incidence of atrial fibrillation/flutter was significantly higher (5% in FS vs 50% in MIT, P < .01). Other exploratory outcomes showed no statistical differences. CONCLUSIONS: Ventilation distribution was impaired after cardiac surgery. The recovery process of ventilation homogeneity was strongly depending on individuals so that MIT was not always superior in this aspect. EIT may help to identify the patients requiring further care after surgery.

Placenta-Derived Mesenchymal Stem Cells Reduce the Interleukin-5 Level Experimentally in Children with Asthma.

Background: Mesenchymal stem cells (MSCs) have been investigated as a new treatment option for various diseases in recent years. However, the role of placenta-derived MSCs in children with asthma remains unclear. We assessed the effect of placenta-derived MSCs on T cell immune responses and cytokine IL-5 levels according to cultures in children with and without asthma. Study design: We enrolled children with and without asthma and recorded asthma symptom scores in the asthma group. Blood samples from children were collected to isolate peripheral blood mononuclear cells (PBMCs) and determine the total IgE level. The PBMCs were cultured in vitro with or without MSCs after stimulation with human anti-CD3 and anti-CD28 antibodies (0.5 µg/mL) to evaluate the effect of placenta-derived MSCs. Flow cytometry was performed to detect the activation and proliferation of CD4+ and CD8+ T cells. Pre- and post-culture IL-5 levels were measured in all samples. Results: The percentages of activation and proliferation among CD4+ and CD8+ T cells after coculture with MSCs were significantly lower in the asthma group (P < 0.05). IL-5 levels differed significantly between the PBMC culture and PBMC + MSC (P+S) coculture in the asthma group (P < 0.05). IL-5 levels differed significantly between the PBMC culture and P+S coculture in both the lower (P < 0.05) and higher (P < 0.0005) IgE asthma subgroups. IL-5 levels were also decreased in children with all severities of asthma (P < 0.05). Conclusions: Placenta-derived MSCs exerted an anti-IL-5 effect and reduced the IL-5 level in culture in different subgroups of children with asthma.

Mechanistic study on uptake and transport of pharmaceuticals in lettuce from water.

The dissemination of pharmaceuticals in agroecosystems originating from land application of animal manure/sewage sludge and irrigation with treated wastewater in agricultural production has raised concern about the accumulation of pharmaceuticals in food products. The pathways of pharmaceutical entries via plant roots, transport to upper fractions, and the factors influencing these processes have yet been systematically elucidated, thus impeding the development of effective measures to mitigate pharmaceutical contamination in food crops. In this study, lettuce uptake of thirteen commonly used pharmaceuticals was investigated using a hydroponic experimental setting. Pharmaceutical sorption by lettuce roots was measured in order to evaluate the influence on pharmaceutical transport from roots to shoots. Small-sized pharmaceuticals e.g., caffeine and carbamazepine with molecular weight (MW) <300 g mol-1 and a low affinity to lettuce roots (sorption coefficient Kp < 0.05 L g-1) manifested substantial transport to shoots. Small-sized molecules lamotrigine and trimethoprim had a relatively strong affinity to lettuce roots (Kp > 12.0 L g-1) and demonstrated a reduced transport to shoots. Large-sized pharmaceuticals (e.g. MW >400 g mol-1) including lincomycin, monensin sodium, and tylosin could be excluded from cell membranes, resulting in the predominant accumulation in lettuce roots. Large-sized oxytetracycline existed as zwitterionic species that could slowly enter lettuce roots; however, the relatively strong interaction with lettuce roots limits its transport to shoots. The mass balance analysis revealed that acetaminophen, ß-estradiol, carbadox, estrone and triclosan were readily metabolized in lettuce with >90% loss during 144-h exposure period. A scheme was proposed to describe pharmaceutical uptake and transport in plant, which could reasonably elucidate many literature-reported results. Molecular size, reactivity and ionic speciation of pharmaceuticals, as well as plant physiology, collectively determine their uptake, transport and accumulation in plants.

Long-term sorption of lincomycin to biochars: The intertwined roles of pore diffusion and dissolved organic carbon.

Sequestration of anthropogenic antibiotics by biochars from waters may be a promising strategy to minimize environmental and human health risks of antibiotic resistance. This study investigated the long-term sequestration of lincomycin by 17 slow-pyrolysis biochars using batch sorption experiments during 365 days. Sorption kinetics were well fitted to the Weber-Morris intraparticle diffusion model for all tested biochars with the intraparticle diffusion rate constant (kid) of 25.3-166 µg g-1 day-0.5 and intercept constant (Cid) of 39.0-339 µg g-1, suggesting that the sorption kinetics were controlled by fast initial sorption and slow pore diffusion. The quasi-equilibrium sorption isotherms became more nonlinear with increasing equilibration time at 1, 7, 30, and 365 days, likely due to increasing abundance of heterogeneous sorption sites in biochars over time. Intriguingly, low-temperature (300 °C) and high-temperature (600 °C) biochars had faster sorption kinetics than intermediate-temperature (400-500 °C) biochars at the long term, which was attributed to greater specific surface area and pore volume of high-temperature biochars and the substantial and continuous release of dissolved organic carbon (DOC) from low-temperature biochars, respectively. DOC release enhanced lincomycin sorption by decreasing biochar particle size and/or increasing the accessibility of sorption sites and pores initially blocked by DOC. Additionally, a large fraction (>75%) of sorbed lincomycin in biochars after a 240-day equilibration could not be extracted by the acetonitrile/methanol extractant. The strong sorption and low extraction recovery demonstrated the great potential of biochars as soil amendments for long-term sequestration of antibiotics in-situ.