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As the most common endocrine cancer, thyroid cancer (TC) has sharply increased globally over the past three decades. The growing incidence of TC might be counted by genetics, radiation, iodine, autoimmune disease, and exposure to environmental endocrine–disrupting chemicals (EDCs). Polybrominated diphenyl ethers (PBDEs), being typical EDCs, have been widely utilized in plastics, electronics, furniture, and textiles as flame retardants since the 1980s, and research has indicated a significant correlation between their exposure and the risk of TC. Even so, PBDEs exposure impact on the metabolic signature for TC remains unexplored. In this study, eight congeners of PBDEs were determined in serum from 111 patents with papillary thyroid cancer (PTC) and 111 healthy participants based on case–control epidemiology using gas chromatography–atmospheric pressure chemical ionization–tandem mass spectrometry (GC-APCI–MS/MS). Based on the tertile distribution of total PBDEs concentrations in 59 participants, metabolomics analysis was further performed by ultra-high performance liquid chromatography coupled to hybrid quadrupole–Orbitrap MS. In the partial correlation analysis, the 29 identified metabolites were correlated with PBDEs exposure (P < 0.05). In addition, PBDEs disrupted the metabolism of glycerophospholipids, sphingolipids, taurine, and hypotaurine, indicating that neurotransmitters, oxidative stress, and inflammation are the vulnerable pathways affected in PTC. Furthermore, (±)-octopamine and 5-hydroxyindole, both of which modulate the actions of neurotransmitters, emerged as potential disturbed metabolite markers for TC following exposure to PBDEs. This study analyzed the impact of PBDEs on PTC in terms of the metabolic changes and further explored possible biomarkers, which helped us have a deep understanding of the possible mechanism of the effects of PBDEs on TC. [ABSTRACT FROM AUTHOR]

Large yellow croaker (Larimichthys crocea) is a vital marine‐cultured species in China. Large yellow croaker iridovirus (LYCIV) can cause a high mortality rate in L. crocea. Rapid and convenient detection of LYCIV is an urgent demand for diagnosis. In this study, rapid and simple recombinase polymerase amplification (RPA), real‐time RPA and RPA combined with lateral flow dipstick (RPA‐LFD) methods were developed for the detection of LYCIV based on the conserved sequence of the LYCIV major capsid protein (MCP) gene. With these optimized RPA analyses, LYCIV detection could be completed within 20 min at 40°C. Both RPA and real‐time RPA could detect viral DNA as low as 102 copies/μL, while the detection limit of RPA‐LFD was 101 copies/μL, and there was no cross‐reaction with other aquatic pathogens (KHV, CyHV‐2, GCRV‐JX01, SVCV, LCDV and LMBV). In practical evaluation of RPA, real‐time RPA and RPA‐LFD methods, the results showed consistency with the general PCR detection. In short, the developed RPA, real‐time RPA and RPA‐LFD analyses could be simple, rapid, sensitive and reliable methods for field diagnosis of LYCIV infection and have significant potential in the protection of LYCIV infection. [ABSTRACT FROM AUTHOR]

Cyprinid herpesvirus 3 (CyHV‐3) is the main pathogen of koi herpesvirus disease (KHVD), which has caused serious damage to the ornamental and food‐producing carp industry. Effective and rapid on‐site detection methods are needed for early diagnosis of CyHV‐3. A lateral flow immuno‐chromatographic assay (LFIA) using two specific anti‐CyHV‐3 monoclonal antibodies has been developed and validated for on‐site detection of CyHV‐3. MAb 3C9 was used to bio‐conjugate CyHV‐3 antigen with colloidal gold, and MAb 2A8 was used to capture antigen bound colloidal gold on the test line. The control line was lined with goat anti‐mouse IgG to capture unbound colloidal gold to validate performance. The test results can be viewed within 10 min after putting the strip into CyHV‐3 virus infection fluid. The lowest limit of detection for the LFIA test was found to be 1.5 × 104 copies/μL and it showed no cross‐reactivity with other fish viral pathogens. The specificity of the strip was 100% when spleen and kidney tissues of CyHV‐3‐infected and healthy koi were validated at the field level. The LFIA strip will be an effective device for the early detection of CyHV‐3 in the future. [ABSTRACT FROM AUTHOR]

Cyprinid herpesvirus 2 (CyHV‐2), the etiological agent of herpesvirus haematopoietic necrosis (HVHN) in carp and goldfish, has caused significant economic losses in the aquaculture industry. During viral infection, the host initiates a series of active or passive defences to regulate the process of virus infection. Apoptosis is a key component of active cellular defence, and members of the Bcl‐2 family have been shown to play a critical role in the apoptotic process. However, the mechanism of action of the Bcl‐2 family in inducing apoptosis during CyHV‐2 infection remains unclear. In this study, we revealed the molecular mechanism of miRNA‐mediated silver crucian carp BAX (ccBax) in CyHV‐2‐induced apoptosis for the first time and demonstrated that the overexpression of miR‐124 suppressed ccBax expression and significantly down‐regulated apoptosis in caudal fin cells of Carassius auratus gibelio (GiCF), while miR‐124 inhibitors were the opposite. These studies indicated that miR‐124 inhibits CyHV‐2‐induced apoptosis by reducing the expression of ccBax. Furthermore, the fact that transfection of miR‐124 mimics promoted CyHV‐2 replication, whereas miR‐124 inhibitors inhibited CyHV‐2 replication, indicated that miR‐124 inhibited CyHV‐2‐induced apoptosis and contributed to viral replication. All these results suggested that miR‐124 suppresses virus‐induced apoptosis and promotes viral replication by targeting and regulating ccBax expression. [ABSTRACT FROM AUTHOR]

Prodigiosin (PG), a member of a family of natural red pigments produced by a variety of bacteria, was first discovered in Serratia marcescens. PG has been reported to have an apoptosis-inducing effect in many cancers, such as lymphoma, colon cancer and nasopharyngeal carcinoma. For this study, we used three glioblastoma (GBM) cell lines (LN229, U251 and A172) to explore the effect of prodigiosin on GBM cells. A CCK8 assay was used to evaluate cell viability. We determinedthe cell cycle distribution by flow cytometry and measured proliferation by an EdU incorporation assay. The expression of different molecules was investigated by western blotting and RT-PCR. We further confirmed our results by plasmid transfection and lentiviral transduction. The LN229 xenograft model was used to study the effect of prodigiosin in vivo. We confirmed that prodigiosin played an anticancer role in several GBM cell lines through the KIAA1524/PP2A/Akt signalling pathway. Prodigiosin inhibited the protein expression of KIAA1524 by suppressing its transcription, which led to activation of PP2A. Afterward, PP2A inhibited the phosphorylation of Akt, thereby inducing increased expression of p53/p21. Furthermore, it was verified that prodigiosin inhibited the KIAA1524/PP2A/Akt axis in vivo in the LN229 xenograft model. These data improve the understanding of the anticancer effects of prodigiosin and further highlight the potential of prodigiosin for the development of anti-glioma drugs. [ABSTRACT FROM AUTHOR]

Infections of Cyprinid herpesvirus 2 in goldfish and farmed crucian carp (Carassius auratus gibelio) are still an urgent problem worldwide. Detection and prevention are necessary for the control of haematopoietic necrosis disease caused by CyHV‐2. Although many sensitive molecular diagnostic methods have been developed, effective immunodiagnosis and neutralization approaches based on monoclonal antibodies (MAbs) against CyHV‐2 are still important to CyHV‐2 study. In this experiment, purified CyHV‐2 was used as antigens to produce monoclonal antibodies (Mabs). Six Mabs bound to different proteins were selected by Dot‐blot screening and Western‐blot analysis, and no one had cross‐reactivity with closely related koi herpesvirus. Among them, Mabs 2E1‐B10, 1F5‐A3 and 4C4‐A7 belonged to IgG1 isotype, while other three Mabs 3G9‐B11, 3B4‐G5 and 4F4‐B7 belonged to IgM isotype. These six Mabs all could specifically detect CyHV‐2 in CyHV‐2 infected caudal fin of Carassius auratus gibelio (GiCF) cells by immunofluorescence assays. Then, the neutralization ability was tested in vitro, and the result showed that all six Mabs can attenuate CPE by CyHV‐2 in vitro among which 2E1‐B10 had the best neutralization ability. The virus proteins recognized by these six Mabs were identified by mass spectrometry identification, and the result showed they probably were ORF88, ORF55R, ORF115 and ORF151R. This study is the first to prepare Mabs by purifying CyHV‐2, which will provide a practical basis for the in‐depth study of CyHV‐2 virus. [ABSTRACT FROM AUTHOR]

Herpesviruses have been reported to be able to encode and express functional viral microRNAs that target both viral and cellular transcripts. In our previous studies, we found a new miRNA miR‐KT‐635 encoded by Cyprinid herpesvirus 2, which is predicted to target viral genes and cellular genes involved in innate immune signalling pathway and apoptosis. However, the function and target gene of miR‐KT‐635 are not proved. In this study, the regulating target gene of miR‐KT‐635 was proved as the viral gene ORF23 directly, the target point sequence on gene was verified and miR‐KT‐635 was identified to regulate the expression of ORF23 protein. According to the bioinformatics analysis, the tRNA domain and ribosome domain in the protein sequence of ORF23 were found to share high homology with R2i and P53R2i, which are related to the ribonucleotide reductase small subunit in the host (transform NTP to dNTP). Within expectations, silencing of viral ORF23 or transfecting miR‐KT‐635 mimics in Carassius auratus gibelio caudal fin cell line (GiCF) could suppress viral propagation significantly. [ABSTRACT FROM AUTHOR]

Cyprinid herpesvirus 2 (CyHV‐2) is a viral pathogen worldwide and causing high mortality on goldfish and silver crucian carp (Carassius auratus gibelio). In order to establish a stable and sensitive immunological diagnostic approach, the recombinant ORF121 protein encoded by the CyHV‐2 ORF121 gene, was selected as a capture antigen to identify cells and tissues infected with CyHV‐2 by immunological methods in this study. Firstly, the open reading frame of CyHV‐2 ORF121 was cloned into the PGEX‐4T‐3 vector and expressed in Escherichia coli. Purified recombinant ORF121 protein was then used as an antigen to prepare monoclonal antibodies, and an efficient hybridoma cell line was selected by dot‐blot assay. The resulting mAb‐3D9 was applied to detect CyHV‐2 in infected caudal fin of Carassius auratus gibelio (GiCF) cells and fish tissues by western blotting, immunofluorescence assays and immunohistological asays. The monoclonal antibody could specifically identify CyHV‐2 in infected GiCF cells and the gills, the kidney and the spleen tissues, and it could attenuate CPE by CyHV‐2 in vitro, suggesting it can be applied for CyHV‐2 detection in the crucian carp and ORF121 may be a candidate vaccine against CyHV‐2. [ABSTRACT FROM AUTHOR]

Largemouth bass (Micropterus salmoides) is an important freshwater‐cultured species in China. Recently, a lethal and epidemic disease caused by Micropterus salmoides rhabdovirus (MSRV) results in huge economic losses to the largemouth bass industry. Current diagnostics for detecting MSRV are limited in sensitivity and speed and are inconvenient to be used for non‐laboratory detection. In this study, three rapid and convenient detection assays of MSRV by recombinase polymerase amplification (RPA) and lateral flow dipsticks (LFD), targeting the conserved sequences of the MSRV‐SS N gene, are described. With these RPA methods, the detection could achieve within 50 min at 38°C. Both methods of RPA‐AGE and RPA‐LFD could detect the viral DNA as low as 170 copies/μl of the MSRV standard plasmid and were 100‐fold more sensitive than that in the method of routine PCR. Meanwhile, these RPA methods were highly specific for the detection of MSRV and can be feasibly applied to the diagnostic of MSRV infection. In brief, RPA‐AGE, RPA‐LFD and RT‐RPA‐LFD provide convenient, rapid, sensitive and reliable methods that could improve field diagnosis of MSRV with limited machine resources, and would enhance the production of largemouth bass. [ABSTRACT FROM AUTHOR]

Background: The incidence rates of thyroid tumors and nodular goiter show an upward trend worldwide. There are limited reports on the risk of perchlorate and iodine on thyroid tumors, but evidence from population studies is scarce, and their impact on thyroid function is still uncertain. Therefore, the objective of this study was to investigate the association of perchlorate and iodine with the risk of nodular goiter (NG), papillary thyroid microcarcinoma (PTMC), and papillary thyroid carcinoma (PTC) and to assess the correlation between perchlorate and iodine with thyroid function indicators.Methods: A case-control population consisting of 184 pairs of thyroid tumors and nodular goiter matched by gender and age (±2 years) was recruited in this study. Serum and urine samples were collected from each participant. Thyroid function indicators in serum were tested by automatic chemical immunofluorescence, and perchlorate and iodine levels in urine were determined by ultra-high performance liquid chromatography tandem-mass spectrometry and inductively coupled plasma-mass spectrometry, respectively. Conditional logistic regressions and multiple linear regressions were used to analyze the associations.Results: Urinary perchlorate concentration was significantly higher in total cases, NG and PTC than in the corresponding controls (P < 0.05). Perchlorate was positively associated with PTC (OR = 1.058, 95% CI: 1.009, 1.110) in a non-linear dose-response relationship, but there was no association between perchlorate and NG or PTMC. Iodine was not associated with the risk of thyroid tumors and NG and did not correlate with the thyroid function indicators. Furthermore, perchlorate showed a positive correlation with thyroid stimulating hormone (TSH) at iodine adequate levels (P < 0.05), and a negative correlation with free triiodothyronine (FT3) and a positive correlation with thyroglobulin antibody (TgAb) at iodine more than adequate or excess levels (P < 0.05).Conclusions: Perchlorate can increase the risk of PTC in a non-linear dose-response relationship and disturb the thyroid hormone homeostasis and thyroid autoantibody levels. [ABSTRACT FROM AUTHOR]

Human milk samples were collected from 179 mothers in 2017 and 2018 in six counties of Guangdong province, China. Concentrations of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) were determined to evaluate the human body burden of dioxin-like compounds on the general population of South China. Samples were analyzed using high-resolution gas chromatography/high-resolution mass spectrometry in six pools, according to the subjects' resident county. The mean ∑PCDD/Fs and ∑DL-PCBs concentrations in human milk samples were 323.10 pg g−1 lipid and 2166.58 pg g−1 lipid, respectively, and the corresponding WHO toxicity equivalent (TEQ) values calculated with Toxic Equivalent Factors (TEFs) established by the WHO in 2005 (TEFWHO 2005) were 6.96 and 2.13 pg g−1 lipid. The concentrations of samples collected in Guangzhou, the capital city of Guangdong Province, were higher than those taken in the other five investigation regions. The levels of PCDD/Fs and DL-PCBs in human milk and the estimated daily intake doses of breast-fed infants were still high when compared with some non-exposure areas in mainland China. TEQ levels of PCDD/Fs and DL-PCBs in the present study have been compared to data obtained from a reported national study conducted in 2011. The mean TEQ (calculated with TEFWHO 2005) of ∑(DL-PCBs + PCDD/Fs) (8.4–9.0 pg g−1 lipid in 2011 vs. 9.09 pg g−1 lipid in 2018) seemed to be relatively stable during the period 2011–2018. These findings and continuing the surveillance of PCDD/Fs and DL-PCBs in human milk will be helpful in furthering our understanding of human exposure to dioxin-like compounds in the general population. [ABSTRACT FROM AUTHOR]

Background: Interferon regulatory factor (IRF) 10 was first found in birds and is present in the genome of other tetrapods (but not humans and mice), as well as in teleost fish. The functional role of IRF10 in vertebrate immunity is relatively unknown compared to IRF1-9. The target of this research was to clone and characterize the IRF10 genes in three economically important fish species that will facilitate future evaluation of this molecule in fish innate and adaptive immunity. Molecular Characterization of IRF10 in Three Fish Species: In the present study, a single IRF10 gene was cloned in grass carp Ctenopharyngodon idella and Asian swamp eel Monopterus albus, and two, named IRF10a and IRF10b, in rainbow trout Oncorhynchus mykiss. The fish IRF10 molecules share highest identities to other vertebrate IRF10s, and have a well conserved DNA binding domain, IRF-associated domain, and an 8 exon/7 intron structure with conserved intron phase. The presence of an upstream ATG or open reading frame (ORF) in the 5’-untranslated region of different fish IRF10 cDNA sequences suggests potential regulation at the translational level, and this has been verified by in vitro transcription/translation experiments of the trout IRF10a cDNA, but would still need to be validated in fish cells. Expression Analysis of IRF10 In Vivo and In Vitro : Both trout IRF10 paralogues are highly expressed in thymus, blood and spleen but are relatively low in head kidney and caudal kidney. Trout IRF10b expression is significantly higher than IRF10a in integumentary tissues i.e. gills, scales, skin, intestine, adipose fin and tail fins, suggesting that IRF10b may be more important in mucosal immunity. The expression of both trout IRF10 paralogues is up-regulated by recombinant IFN-γ. The expression of the IRF10 genes is highly induced by Poly I:C in vitro and in vivo, and by viral infection, but is less responsive to peptidoglycan and bacterial infection, suggesting an important role of fish IRF10 in antiviral defense. [ABSTRACT FROM AUTHOR]

This study identifies four new IL-17A/F isoforms in salmonids, as well as IL-17N. IL-17A/F1 and IL-17A/F2 are each represented by two paralogues, with a predicted pseudogene of IL-17N also apparent in the salmonid genome. Analysis of the sequences and genes of the known IL-17A/F and IL-17N molecules suggests that IL-17N is a member within the IL-17A/F subfamily. Analysis of factors that modulated the expression of these genes showed that PHA and PMA were good inducers of salmon IL-17A/F1a and IL-17A/F2a, with rIL-21 a potent stimulator of IL-17A/F1a and IL-17A/F3. The potential involvement of these isoforms during responses post-vaccination and infection was also studied. In unvaccinated control fish, Yersinia ruckeri infection resulted in a marked up-regulation of IL-17A/F1a and IL-17N in the spleen and head kidney and IL-17A/F2a and IL-17A/F3 in the spleen. In the vaccinated fish, only one significant increase was seen relative to control fish, of IL-17A/F2a in the gills, whether the fish were challenged with Y. ruckeri or given the saline placebo. It was also apparent in the gills and head kidney that the level of IL-17A/F1b remained elevated in the Y. ruckeri-challenged fish at a time when it had decreased in saline-injected fish. The relative importance of these isoforms for disease resistance remains to be determined. [ABSTRACT FROM AUTHOR]

Malachite green (MG), a dye, is an antifungal agent that has been used to treat and prevent fish diseases. It is metabolized into reduced leucomalachite green forms (LMG) that may reside in fish muscles for a long period, thus being harmful to human health. The aim of this study was to develop a competitive and direct enzyme-linked immunosorbent assay (ELISA) to detect MG and LMG specifically. The monoclonal antibody (mAb) to LMG was generated using a hybridoma technique. The obtained mAb showed good cross-reactivity (CR) to malachite green (MG), but not to crystal violet (CV) and Brilliant Green (BG). The mAb was used to develop a fast detecting ELISA of MG and LMG in fish. By introducing the conjugation LMG-HRP, the detection capability was 0.37 ng mL for MG and LMG. The mean recovery from spiked grass carp tissues ranged from 76.2% to 82.9% and the coefficients of variation varied between 1.8% and 7.5%. The stable and efficient monoclonal cell line obtained is a sustainable source of sensitive and specific antibody to MG and LMG. [ABSTRACT FROM AUTHOR]

Perfluorinated compounds (PFCs) have been detected in many environmental matrices, biota, and nonoccupationally exposed populations in China recently. However, little is known about the distribution and levels of various PFCs in the general population living in areas where there is PFC exposure. In the present study, the levels and prevalence of ten target PFCs were determined in 227 serum samples from a population of nonoccupationally exposed individuals in Shenzhen, China. Results indicated that human exposure to PFCs was prevalent in Shenzhen. Perfluorooctanoate (PFOA) was the dominant PFC contaminant in the serum samples, with a median concentration of 6.72 ng/mL, followed by perfluorooctane sulfonate (PFOS) with a median concentration of 2.07 ng/mL. Other PFCs were detected at much lower concentrations, with median concentrations ranging from 0.02 to 0.87 ng/mL. Statistically, no significant ( P>0.05) gender differences were observed for any of the PFCs. Significant ( P<0.01) positive correlations were found between age and serum concentrations of the target PFCs, except for perfluorobutane sulfonate ( R = −0.16, P = 0.01), perfluorohexanoic acid ( R = 0.08, P = 0.22), and perfluoroheptanoic acid ( R = −0.11, P = 0.10). Based on the one-compartment pharmacokinetic model, the total daily intakes of PFOA and PFOS for the general population in Shenzhen were calculated as 0.63 and 0.20 ng/kg body weight/day, respectively. [ABSTRACT FROM AUTHOR]